version 3.1

forever loop is gone (use repeat without iteration count).
struct literal is now same as array literal [...] to avoid parsing ambiguity with scope blocks.

.gitignore

@@ -1,7 +1,8 @@
 .idea/workspace.xml
-/build/
-/dist/
-/output/
+.idea/discord.xml
+build/
+dist/
+output/
 .*cache/
 *.directory
 *.prg
@@ -11,9 +12,9 @@
 *.vice-mon-list
 docs/build
 out/
-**/*.interp
-**/*.tokens
-
+parser/**/*.interp
+parser/**/*.tokens
+parser/**/*.java
 *.py[cod]
 *.egg
 *.egg-info
@@ -27,5 +28,4 @@ parsetab.py
 .attach_pid*
 
 .gradle
-build/
 /prog8compiler.jar

.idea/inspectionProfiles/Project_Default.xml

@@ -1,6 +1,16 @@
 <component name="InspectionProjectProfileManager">
   <profile version="1.0">
     <option name="myName" value="Project Default" />
+    <inspection_tool class="DuplicatedCode" enabled="true" level="WEAK WARNING" enabled_by_default="true">
+      <Languages>
+        <language minSize="100" isEnabled="false" name="JavaScript" />
+        <language isEnabled="false" name="Groovy" />
+        <language isEnabled="false" name="Style Sheets" />
+        <language minSize="70" name="Kotlin" />
+        <language isEnabled="false" name="TypeScript" />
+        <language isEnabled="false" name="ActionScript" />
+      </Languages>
+    </inspection_tool>
     <inspection_tool class="SpellCheckingInspection" enabled="true" level="TYPO" enabled_by_default="true">
       <option name="processCode" value="false" />
       <option name="processLiterals" value="true" />

.idea/libraries/antlr_4_8_complete.xml

@@ -0,0 +1,9 @@
+<component name="libraryTable">
+  <library name="antlr-4.8-complete">
+    <CLASSES>
+      <root url="jar://$PROJECT_DIR$/parser/antlr/lib/antlr-4.8-complete.jar!/" />
+    </CLASSES>
+    <JAVADOC />
+    <SOURCES />
+  </library>
+</component>

.idea/libraries/antlr_runtime_4_8.xml

@@ -0,0 +1,9 @@
+<component name="libraryTable">
+  <library name="antlr-runtime-4.8">
+    <CLASSES>
+      <root url="jar://$PROJECT_DIR$/parser/antlr/lib/antlr-runtime-4.8.jar!/" />
+    </CLASSES>
+    <JAVADOC />
+    <SOURCES />
+  </library>
+</component>

.idea/libraries/kotlinx_cli_jvm_0_1_0_dev_5.xml

@@ -0,0 +1,9 @@
+<component name="libraryTable">
+  <library name="kotlinx-cli-jvm-0.1.0-dev-5">
+    <CLASSES>
+      <root url="jar://$PROJECT_DIR$/compiler/lib/kotlinx-cli-jvm-0.1.0-dev-5.jar!/" />
+    </CLASSES>
+    <JAVADOC />
+    <SOURCES />
+  </library>
+</component>

.idea/markdown-navigator-enh.xml

@@ -0,0 +1,29 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="MarkdownEnhProjectSettings">
+    <AnnotatorSettings targetHasSpaces="true" linkCaseMismatch="true" wikiCaseMismatch="true" wikiLinkHasDashes="true" notUnderWikiHome="true" targetNotWikiPageExt="true" notUnderSourceWikiHome="true" targetNameHasAnchor="true" targetPathHasAnchor="true" wikiLinkHasSlash="true" wikiLinkHasSubdir="true" wikiLinkHasOnlyAnchor="true" linkTargetsWikiHasExt="true" linkTargetsWikiHasBadExt="true" notUnderSameRepo="true" targetNotUnderVcs="false" linkNeedsExt="true" linkHasBadExt="true" linkTargetNeedsExt="true" linkTargetHasBadExt="true" wikiLinkNotInWiki="true" imageTargetNotInRaw="true" repoRelativeAcrossVcsRoots="true" multipleWikiTargetsMatch="true" unresolvedLinkReference="true" linkIsIgnored="true" anchorIsIgnored="true" anchorIsUnresolved="true" anchorLineReferenceIsUnresolved="true" anchorLineReferenceFormat="true" anchorHasDuplicates="true" abbreviationDuplicates="true" abbreviationNotUsed="true" attributeIdDuplicateDefinition="true" attributeIdNotUsed="true" footnoteDuplicateDefinition="true" footnoteUnresolved="true" footnoteDuplicates="true" footnoteNotUsed="true" macroDuplicateDefinition="true" macroUnresolved="true" macroDuplicates="true" macroNotUsed="true" referenceDuplicateDefinition="true" referenceUnresolved="true" referenceDuplicates="true" referenceNotUsed="true" referenceUnresolvedNumericId="true" enumRefDuplicateDefinition="true" enumRefUnresolved="true" enumRefDuplicates="true" enumRefNotUsed="true" enumRefLinkUnresolved="true" enumRefLinkDuplicates="true" simTocUpdateNeeded="true" simTocTitleSpaceNeeded="true" />
+    <HtmlExportSettings updateOnSave="false" parentDir="" targetDir="" cssDir="css" scriptDir="js" plainHtml="false" imageDir="" copyLinkedImages="false" imagePathType="0" targetPathType="2" targetExt="" useTargetExt="false" noCssNoScripts="false" useElementStyleAttribute="false" linkToExportedHtml="true" exportOnSettingsChange="true" regenerateOnProjectOpen="false" linkFormatType="HTTP_ABSOLUTE" />
+    <LinkMapSettings>
+      <textMaps />
+    </LinkMapSettings>
+  </component>
+  <component name="MarkdownNavigatorHistory">
+    <PasteImageHistory checkeredTransparentBackground="false" filename="image" directory="" onPasteImageTargetRef="3" onPasteLinkText="0" onPasteImageElement="1" onPasteLinkElement="1" onPasteReferenceElement="2" cornerRadius="20" borderColor="0" transparentColor="16777215" borderWidth="1" trimTop="0" trimBottom="0" trimLeft="0" trimRight="0" transparent="false" roundCorners="false" showPreview="true" bordered="false" scaled="false" cropped="false" hideInapplicableOperations="false" preserveLinkFormat="false" scale="50" scalingInterpolation="1" transparentTolerance="0" saveAsDefaultOnOK="false" linkFormat="0" addHighlights="false" showHighlightCoordinates="true" showHighlights="false" mouseSelectionAddsHighlight="false" outerFilled="false" outerFillColor="0" outerFillTransparent="true" outerFillAlpha="30">
+      <highlightList />
+      <directories />
+      <filenames />
+    </PasteImageHistory>
+    <CopyImageHistory checkeredTransparentBackground="false" filename="image" directory="" onPasteImageTargetRef="3" onPasteLinkText="0" onPasteImageElement="1" onPasteLinkElement="1" onPasteReferenceElement="2" cornerRadius="20" borderColor="0" transparentColor="16777215" borderWidth="1" trimTop="0" trimBottom="0" trimLeft="0" trimRight="0" transparent="false" roundCorners="false" showPreview="true" bordered="false" scaled="false" cropped="false" hideInapplicableOperations="false" preserveLinkFormat="false" scale="50" scalingInterpolation="1" transparentTolerance="0" saveAsDefaultOnOK="false" linkFormat="0" addHighlights="false" showHighlightCoordinates="true" showHighlights="false" mouseSelectionAddsHighlight="false" outerFilled="false" outerFillColor="0" outerFillTransparent="true" outerFillAlpha="30">
+      <highlightList />
+      <directories />
+      <filenames />
+    </CopyImageHistory>
+    <PasteLinkHistory onPasteImageTargetRef="3" onPasteTargetRef="1" onPasteLinkText="0" onPasteImageElement="1" onPasteLinkElement="1" onPasteWikiElement="2" onPasteReferenceElement="2" hideInapplicableOperations="false" preserveLinkFormat="false" useHeadingForLinkText="false" linkFormat="0" saveAsDefaultOnOK="false" />
+    <TableToJsonHistory>
+      <entries />
+    </TableToJsonHistory>
+    <TableSortHistory>
+      <entries />
+    </TableSortHistory>
+  </component>
+</project>

.idea/markdown-navigator.xml

@@ -0,0 +1,57 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="FlexmarkProjectSettings">
+    <FlexmarkHtmlSettings flexmarkSpecExampleRendering="0" flexmarkSpecExampleRenderHtml="false">
+      <flexmarkSectionLanguages>
+        <option name="1" value="Markdown" />
+        <option name="2" value="HTML" />
+        <option name="3" value="flexmark-ast:1" />
+      </flexmarkSectionLanguages>
+    </FlexmarkHtmlSettings>
+  </component>
+  <component name="MarkdownProjectSettings">
+    <PreviewSettings splitEditorLayout="SPLIT" splitEditorPreview="PREVIEW" useGrayscaleRendering="false" zoomFactor="1.0" maxImageWidth="0" synchronizePreviewPosition="true" highlightPreviewType="LINE" highlightFadeOut="5" highlightOnTyping="true" synchronizeSourcePosition="true" verticallyAlignSourceAndPreviewSyncPosition="true" showSearchHighlightsInPreview="true" showSelectionInPreview="true" lastLayoutSetsDefault="false">
+      <PanelProvider>
+        <provider providerId="com.vladsch.md.nav.editor.javafx.html.panel" providerName="JavaFX WebView" />
+      </PanelProvider>
+    </PreviewSettings>
+    <ParserSettings gitHubSyntaxChange="false" correctedInvalidSettings="false" emojiShortcuts="1" emojiImages="0">
+      <PegdownExtensions>
+        <option name="ANCHORLINKS" value="true" />
+        <option name="ATXHEADERSPACE" value="true" />
+        <option name="FENCED_CODE_BLOCKS" value="true" />
+        <option name="INTELLIJ_DUMMY_IDENTIFIER" value="true" />
+        <option name="RELAXEDHRULES" value="true" />
+        <option name="STRIKETHROUGH" value="true" />
+        <option name="TABLES" value="true" />
+        <option name="TASKLISTITEMS" value="true" />
+      </PegdownExtensions>
+      <ParserOptions>
+        <option name="COMMONMARK_LISTS" value="true" />
+        <option name="EMOJI_SHORTCUTS" value="true" />
+        <option name="GFM_TABLE_RENDERING" value="true" />
+        <option name="PRODUCTION_SPEC_PARSER" value="true" />
+        <option name="SIM_TOC_BLANK_LINE_SPACER" value="true" />
+      </ParserOptions>
+    </ParserSettings>
+    <HtmlSettings headerTopEnabled="false" headerBottomEnabled="false" bodyTopEnabled="false" bodyBottomEnabled="false" addPageHeader="false" imageUriSerials="false" addDocTypeHtml="true" noParaTags="false" plantUmlConversion="0">
+      <GeneratorProvider>
+        <provider providerId="com.vladsch.md.nav.editor.javafx.html.generator" providerName="JavaFx HTML Generator" />
+      </GeneratorProvider>
+      <headerTop />
+      <headerBottom />
+      <bodyTop />
+      <bodyBottom />
+    </HtmlSettings>
+    <CssSettings previewScheme="UI_SCHEME" cssUri="" isCssUriEnabled="false" isCssUriSerial="true" isCssTextEnabled="false" isDynamicPageWidth="true">
+      <StylesheetProvider>
+        <provider providerId="com.vladsch.md.nav.editor.javafx.html.css" providerName="Default JavaFx Stylesheet" />
+      </StylesheetProvider>
+      <ScriptProviders>
+        <provider providerId="com.vladsch.md.nav.editor.hljs.html.script" providerName="HighlightJS Script" />
+      </ScriptProviders>
+      <cssText />
+      <cssUriHistory />
+    </CssSettings>
+  </component>
+</project>

.idea/misc.xml

@@ -1,5 +1,21 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project version="4">
+  <component name="ANTLRGenerationPreferences">
+    <option name="perGrammarGenerationSettings">
+      <list>
+        <PerGrammarGenerationSettings>
+          <option name="fileName" value="$PROJECT_DIR$/parser/antlr/prog8.g4" />
+          <option name="autoGen" value="true" />
+          <option name="outputDir" value="$PROJECT_DIR$/parser/src/prog8/parser" />
+          <option name="libDir" value="" />
+          <option name="encoding" value="" />
+          <option name="pkg" value="" />
+          <option name="language" value="" />
+          <option name="generateListener" value="false" />
+        </PerGrammarGenerationSettings>
+      </list>
+    </option>
+  </component>
   <component name="ProjectRootManager" version="2" languageLevel="JDK_1_8" default="false" project-jdk-name="Kotlin SDK" project-jdk-type="KotlinSDK">
     <output url="file://$PROJECT_DIR$/out" />
   </component>

.idea/modules.xml

@@ -2,7 +2,6 @@
 <project version="4">
   <component name="ProjectModuleManager">
     <modules>
-      <module fileurl="file://$PROJECT_DIR$/DeprecatedStackVm/DeprecatedStackVm.iml" filepath="$PROJECT_DIR$/DeprecatedStackVm/DeprecatedStackVm.iml" />
       <module fileurl="file://$PROJECT_DIR$/compiler/compiler.iml" filepath="$PROJECT_DIR$/compiler/compiler.iml" />
       <module fileurl="file://$PROJECT_DIR$/docs/docs.iml" filepath="$PROJECT_DIR$/docs/docs.iml" />
       <module fileurl="file://$PROJECT_DIR$/examples/examples.iml" filepath="$PROJECT_DIR$/examples/examples.iml" />

.idea/vcs.xml

@@ -3,4 +3,4 @@
   <component name="VcsDirectoryMappings">
     <mapping directory="$PROJECT_DIR$" vcs="Git" />
   </component>
-</project>
+</project>

.travis.yml

@@ -1,10 +1,10 @@
 language: java
+sudo: false
 # jdk: openjdk8
 # dist: xenial
-# sudo: false
 
 before_install:
-  - chmod +x gradlew
+  - chmod +x ./gradlew
 
 script:
   - ./gradlew test

DeprecatedStackVm/DeprecatedStackVm.iml

@@ -1,10 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<module type="JAVA_MODULE" version="4">
-  <component name="NewModuleRootManager" inherit-compiler-output="true">
-    <exclude-output />
-    <content url="file://$MODULE_DIR$" />
-    <orderEntry type="inheritedJdk" />
-    <orderEntry type="sourceFolder" forTests="false" />
-    <orderEntry type="library" name="KotlinJavaRuntime" level="project" />
-  </component>
-</module>

DeprecatedStackVm/src/compiler/intermediate/Instruction.kt

@@ -1,51 +0,0 @@
-package compiler.intermediate
-
-import prog8.vm.RuntimeValue
-import prog8.vm.stackvm.Syscall
-
-open class Instruction(val opcode: Opcode,
-                       val arg: RuntimeValue? = null,
-                       val arg2: RuntimeValue? = null,
-                       val callLabel: String? = null,
-                       val callLabel2: String? = null)
-{
-    var branchAddress: Int? = null
-
-    override fun toString(): String {
-        val argStr = arg?.toString() ?: ""
-        val result =
-                when {
-                    opcode== Opcode.LINE -> "_line  $callLabel"
-                    opcode== Opcode.INLINE_ASSEMBLY -> {
-                        // inline assembly is not written out (it can't be processed as intermediate language)
-                        // instead, it is converted into a system call that can be intercepted by the vm
-                        if(callLabel!=null)
-                            "syscall  SYSASM.$callLabel\n    return"
-                        else
-                            "inline_assembly"
-                    }
-                    opcode== Opcode.INCLUDE_FILE -> {
-                        "include_file \"$callLabel\" $arg $arg2"
-                    }
-                    opcode== Opcode.SYSCALL -> {
-                        val syscall = Syscall.values().find { it.callNr==arg!!.numericValue() }
-                        "syscall  $syscall"
-                    }
-                    opcode in opcodesWithVarArgument -> {
-                        // opcodes that manipulate a variable
-                        "${opcode.name.toLowerCase()}  ${callLabel?:""}  ${callLabel2?:""}".trimEnd()
-                    }
-                    callLabel==null -> "${opcode.name.toLowerCase()}  $argStr"
-                    else -> "${opcode.name.toLowerCase()}  $callLabel  $argStr"
-                }
-                .trimEnd()
-
-        return "    $result"
-    }
-}
-
-class LabelInstr(val name: String, val asmProc: Boolean) : Instruction(Opcode.NOP, null, null) {
-    override fun toString(): String {
-        return "\n$name:"
-    }
-}

DeprecatedStackVm/src/compiler/intermediate/IntermediateProgram.kt

@@ -1,548 +0,0 @@
-package compiler.intermediate
-
-import prog8.ast.antlr.escape
-import prog8.ast.base.*
-import prog8.ast.expressions.NumericLiteralValue
-import prog8.ast.expressions.ReferenceLiteralValue
-import prog8.ast.statements.StructDecl
-import prog8.ast.statements.VarDecl
-import prog8.ast.statements.ZeropageWish
-import prog8.compiler.CompilerException
-import prog8.compiler.HeapValues
-import prog8.compiler.Zeropage
-import prog8.compiler.ZeropageDepletedError
-import prog8.vm.RuntimeValue
-import java.io.PrintStream
-import java.nio.file.Path
-
-
-class IntermediateProgram(val name: String, var loadAddress: Int, val heap: HeapValues, val source: Path) {
-
-    class VariableParameters (val zp: ZeropageWish, val memberOfStruct: StructDecl?)
-    class Variable(val scopedname: String, val value: RuntimeValue, val params: VariableParameters)
-
-    class ProgramBlock(val name: String,
-                       var address: Int?,
-                       val instructions: MutableList<Instruction> = mutableListOf(),
-                       val variables: MutableList<Variable> = mutableListOf(),
-                       val memoryPointers: MutableMap<String, Pair<Int, DataType>> = mutableMapOf(),
-                       val labels: MutableMap<String, Instruction> = mutableMapOf(),        // names are fully scoped
-                       val force_output: Boolean)
-
-    val allocatedZeropageVariables = mutableMapOf<String, Pair<Int, DataType>>()
-    val blocks = mutableListOf<ProgramBlock>()
-    val memory = mutableMapOf<Int, List<RuntimeValue>>()
-    private lateinit var currentBlock: ProgramBlock
-
-    fun allocateZeropage(zeropage: Zeropage) {          // TODO not used anymore???
-        // allocates all @zp marked variables on the zeropage (for all blocks, as long as there is space in the ZP)
-        var notAllocated = 0
-        for(block in blocks) {
-            val zpVariables = block.variables.filter { it.params.zp==ZeropageWish.REQUIRE_ZEROPAGE || it.params.zp==ZeropageWish.PREFER_ZEROPAGE }
-            if (zpVariables.isNotEmpty()) {
-                for (variable in zpVariables) {
-                    if(variable.params.zp==ZeropageWish.NOT_IN_ZEROPAGE || variable.params.memberOfStruct!=null)
-                        throw CompilerException("zp conflict")
-                    try {
-                        val address = zeropage.allocate(variable.scopedname, variable.value.type, null)
-                        allocatedZeropageVariables[variable.scopedname] = Pair(address, variable.value.type)
-                    } catch (x: ZeropageDepletedError) {
-                        printWarning(x.toString() + " variable ${variable.scopedname} type ${variable.value.type}")
-                        notAllocated++
-                    }
-                }
-            }
-        }
-        if(notAllocated>0)
-            printWarning("$notAllocated variables marked for Zeropage could not be allocated there")
-    }
-
-    fun optimize() {
-        println("Optimizing stackVM code...")
-        // remove nops (that are not a label)
-        for (blk in blocks) {
-            blk.instructions.removeIf { it.opcode== Opcode.NOP && it !is LabelInstr }
-        }
-
-        optimizeDataConversionAndUselessDiscards()
-        optimizeVariableCopying()
-        optimizeMultipleSequentialLineInstrs()
-        optimizeCallReturnIntoJump()
-        optimizeConditionalBranches()
-        // todo: add more optimizations to intermediate code!
-
-        optimizeRemoveNops()    //  must be done as the last step
-        optimizeMultipleSequentialLineInstrs()      // once more
-        optimizeRemoveNops()    // once more
-    }
-
-    private fun optimizeConditionalBranches() {
-        // conditional branches that consume the value on the stack
-        // sometimes these are just constant values, so we can statically determine the branch
-        // or, they are preceded by a NOT instruction so we can simply remove that and flip the branch condition
-        val pushvalue = setOf(Opcode.PUSH_BYTE, Opcode.PUSH_WORD)
-        val notvalue = setOf(Opcode.NOT_BYTE, Opcode.NOT_WORD)
-        val branchOpcodes = setOf(Opcode.JZ, Opcode.JNZ, Opcode.JZW, Opcode.JNZW)
-        for(blk in blocks) {
-            val instructionsToReplace = mutableMapOf<Int, Instruction>()
-            blk.instructions.asSequence().withIndex().filter {it.value.opcode!= Opcode.LINE }.windowed(2).toList().forEach {
-                if (it[1].value.opcode in branchOpcodes) {
-                    if (it[0].value.opcode in pushvalue) {
-                        val value = it[0].value.arg!!.asBoolean
-                        instructionsToReplace[it[0].index] = Instruction(Opcode.NOP)
-                        val replacement: Instruction =
-                                if (value) {
-                                    when (it[1].value.opcode) {
-                                        Opcode.JNZ -> Instruction(Opcode.JUMP, callLabel = it[1].value.callLabel)
-                                        Opcode.JNZW -> Instruction(Opcode.JUMP, callLabel = it[1].value.callLabel)
-                                        else -> Instruction(Opcode.NOP)
-                                    }
-                                } else {
-                                    when (it[1].value.opcode) {
-                                        Opcode.JZ -> Instruction(Opcode.JUMP, callLabel = it[1].value.callLabel)
-                                        Opcode.JZW -> Instruction(Opcode.JUMP, callLabel = it[1].value.callLabel)
-                                        else -> Instruction(Opcode.NOP)
-                                    }
-                                }
-                        instructionsToReplace[it[1].index] = replacement
-                    }
-                    else if (it[0].value.opcode in notvalue) {
-                        instructionsToReplace[it[0].index] = Instruction(Opcode.NOP)
-                        val replacement: Instruction =
-                                when (it[1].value.opcode) {
-                                    Opcode.JZ -> Instruction(Opcode.JNZ, callLabel = it[1].value.callLabel)
-                                    Opcode.JZW -> Instruction(Opcode.JNZW, callLabel = it[1].value.callLabel)
-                                    Opcode.JNZ -> Instruction(Opcode.JZ, callLabel = it[1].value.callLabel)
-                                    Opcode.JNZW -> Instruction(Opcode.JZW, callLabel = it[1].value.callLabel)
-                                    else -> Instruction(Opcode.NOP)
-                                }
-                        instructionsToReplace[it[1].index] = replacement
-                    }
-                }
-            }
-
-            for (rins in instructionsToReplace) {
-                blk.instructions[rins.key] = rins.value
-            }
-        }
-    }
-
-    private fun optimizeRemoveNops() {
-        // remove nops (that are not a label)
-        for (blk in blocks)
-            blk.instructions.removeIf { it.opcode== Opcode.NOP && it !is LabelInstr }
-    }
-
-    private fun optimizeCallReturnIntoJump() {
-        // replaces call X followed by return, by jump X
-        for(blk in blocks) {
-            val instructionsToReplace = mutableMapOf<Int, Instruction>()
-
-            blk.instructions.asSequence().withIndex().filter {it.value.opcode!= Opcode.LINE }.windowed(2).toList().forEach {
-                if(it[0].value.opcode== Opcode.CALL && it[1].value.opcode== Opcode.RETURN) {
-                    instructionsToReplace[it[1].index] = Instruction(Opcode.JUMP, callLabel = it[0].value.callLabel)
-                    instructionsToReplace[it[0].index] = Instruction(Opcode.NOP)
-                }
-            }
-
-            for (rins in instructionsToReplace) {
-                blk.instructions[rins.key] = rins.value
-            }
-        }
-    }
-
-    private fun optimizeMultipleSequentialLineInstrs() {
-        for(blk in blocks) {
-            val instructionsToReplace = mutableMapOf<Int, Instruction>()
-
-            blk.instructions.asSequence().withIndex().windowed(2).toList().forEach {
-                if (it[0].value.opcode == Opcode.LINE && it[1].value.opcode == Opcode.LINE)
-                    instructionsToReplace[it[0].index] = Instruction(Opcode.NOP)
-            }
-
-            for (rins in instructionsToReplace) {
-                blk.instructions[rins.key] = rins.value
-            }
-        }
-    }
-
-    private fun optimizeVariableCopying() {
-        for(blk in blocks) {
-
-            val instructionsToReplace = mutableMapOf<Int, Instruction>()
-
-            blk.instructions.asSequence().withIndex().windowed(2).toList().forEach {
-                when (it[0].value.opcode) {
-                    Opcode.PUSH_VAR_BYTE ->
-                        if (it[1].value.opcode == Opcode.POP_VAR_BYTE) {
-                            if (it[0].value.callLabel == it[1].value.callLabel) {
-                                instructionsToReplace[it[0].index] = Instruction(Opcode.NOP)
-                                instructionsToReplace[it[1].index] = Instruction(Opcode.NOP)
-                            }
-                        }
-                    Opcode.PUSH_VAR_WORD ->
-                        if (it[1].value.opcode == Opcode.POP_VAR_WORD) {
-                            if (it[0].value.callLabel == it[1].value.callLabel) {
-                                instructionsToReplace[it[0].index] = Instruction(Opcode.NOP)
-                                instructionsToReplace[it[1].index] = Instruction(Opcode.NOP)
-                            }
-                        }
-                    Opcode.PUSH_VAR_FLOAT ->
-                        if (it[1].value.opcode == Opcode.POP_VAR_FLOAT) {
-                            if (it[0].value.callLabel == it[1].value.callLabel) {
-                                instructionsToReplace[it[0].index] = Instruction(Opcode.NOP)
-                                instructionsToReplace[it[1].index] = Instruction(Opcode.NOP)
-                            }
-                        }
-                    Opcode.PUSH_MEM_B, Opcode.PUSH_MEM_UB ->
-                        if(it[1].value.opcode == Opcode.POP_MEM_BYTE) {
-                            if(it[0].value.arg == it[1].value.arg) {
-                                instructionsToReplace[it[0].index] = Instruction(Opcode.NOP)
-                                instructionsToReplace[it[1].index] = Instruction(Opcode.NOP)
-                            }
-                        }
-                    Opcode.PUSH_MEM_W, Opcode.PUSH_MEM_UW ->
-                        if(it[1].value.opcode == Opcode.POP_MEM_WORD) {
-                            if(it[0].value.arg == it[1].value.arg) {
-                                instructionsToReplace[it[0].index] = Instruction(Opcode.NOP)
-                                instructionsToReplace[it[1].index] = Instruction(Opcode.NOP)
-                            }
-                        }
-                    Opcode.PUSH_MEM_FLOAT ->
-                        if(it[1].value.opcode == Opcode.POP_MEM_FLOAT) {
-                            if(it[0].value.arg == it[1].value.arg) {
-                                instructionsToReplace[it[0].index] = Instruction(Opcode.NOP)
-                                instructionsToReplace[it[1].index] = Instruction(Opcode.NOP)
-                            }
-                        }
-                    else -> {}
-                }
-            }
-
-            for (rins in instructionsToReplace) {
-                blk.instructions[rins.key] = rins.value
-            }
-        }
-    }
-
-    private fun optimizeDataConversionAndUselessDiscards() {
-        // - push value followed by a data type conversion -> push the value in the correct type and remove the conversion
-        // - push something followed by a discard -> remove both
-        val instructionsToReplace = mutableMapOf<Int, Instruction>()
-
-        fun optimizeDiscardAfterPush(index0: Int, index1: Int, ins1: Instruction) {
-            if (ins1.opcode == Opcode.DISCARD_FLOAT || ins1.opcode == Opcode.DISCARD_WORD || ins1.opcode == Opcode.DISCARD_BYTE) {
-                instructionsToReplace[index0] = Instruction(Opcode.NOP)
-                instructionsToReplace[index1] = Instruction(Opcode.NOP)
-            }
-        }
-
-        fun optimizeFloatConversion(index0: Int, index1: Int, ins1: Instruction) {
-            when (ins1.opcode) {
-                Opcode.DISCARD_FLOAT -> {
-                    instructionsToReplace[index0] = Instruction(Opcode.NOP)
-                    instructionsToReplace[index1] = Instruction(Opcode.NOP)
-                }
-                Opcode.DISCARD_BYTE, Opcode.DISCARD_WORD -> throw CompilerException("invalid discard type following a float")
-                else -> throw CompilerException("invalid conversion opcode ${ins1.opcode} following a float")
-            }
-        }
-
-        fun optimizeWordConversion(index0: Int, ins0: Instruction, index1: Int, ins1: Instruction) {
-            when (ins1.opcode) {
-                Opcode.CAST_UW_TO_B, Opcode.CAST_W_TO_B -> {
-                    val ins = Instruction(Opcode.PUSH_BYTE, ins0.arg!!.cast(DataType.BYTE))
-                    instructionsToReplace[index0] = ins
-                    instructionsToReplace[index1] = Instruction(Opcode.NOP)
-                }
-                Opcode.CAST_W_TO_UB, Opcode.CAST_UW_TO_UB -> {
-                    val ins = Instruction(Opcode.PUSH_BYTE, RuntimeValue(DataType.UBYTE, ins0.arg!!.integerValue() and 255))
-                    instructionsToReplace[index0] = ins
-                    instructionsToReplace[index1] = Instruction(Opcode.NOP)
-                }
-                Opcode.MSB -> {
-                    val ins = Instruction(Opcode.PUSH_BYTE, RuntimeValue(DataType.UBYTE, ins0.arg!!.integerValue() ushr 8 and 255))
-                    instructionsToReplace[index0] = ins
-                    instructionsToReplace[index1] = Instruction(Opcode.NOP)
-                }
-                Opcode.CAST_W_TO_F, Opcode.CAST_UW_TO_F -> {
-                    val ins = Instruction(Opcode.PUSH_FLOAT, RuntimeValue(DataType.FLOAT, ins0.arg!!.integerValue().toDouble()))
-                    instructionsToReplace[index0] = ins
-                    instructionsToReplace[index1] = Instruction(Opcode.NOP)
-                }
-                Opcode.CAST_UW_TO_W -> {
-                    val cv = ins0.arg!!.cast(DataType.WORD)
-                    instructionsToReplace[index0] = Instruction(Opcode.PUSH_WORD, cv)
-                    instructionsToReplace[index1] = Instruction(Opcode.NOP)
-                }
-                Opcode.CAST_W_TO_UW -> {
-                    val cv = ins0.arg!!.cast(DataType.UWORD)
-                    instructionsToReplace[index0] = Instruction(Opcode.PUSH_WORD, cv)
-                    instructionsToReplace[index1] = Instruction(Opcode.NOP)
-                }
-                Opcode.DISCARD_WORD -> {
-                    instructionsToReplace[index0] = Instruction(Opcode.NOP)
-                    instructionsToReplace[index1] = Instruction(Opcode.NOP)
-                }
-                Opcode.DISCARD_BYTE, Opcode.DISCARD_FLOAT -> throw CompilerException("invalid discard type following a byte")
-                else -> throw CompilerException("invalid conversion opcode ${ins1.opcode} following a word")
-            }
-        }
-
-        fun optimizeByteConversion(index0: Int, ins0: Instruction, index1: Int, ins1: Instruction) {
-            when (ins1.opcode) {
-                Opcode.CAST_B_TO_UB, Opcode.CAST_UB_TO_B,
-                Opcode.CAST_W_TO_B, Opcode.CAST_W_TO_UB,
-                Opcode.CAST_UW_TO_B, Opcode.CAST_UW_TO_UB -> instructionsToReplace[index1] = Instruction(Opcode.NOP)
-                Opcode.MSB -> throw CompilerException("msb of a byte")
-                Opcode.CAST_UB_TO_UW -> {
-                    val ins = Instruction(Opcode.PUSH_WORD, RuntimeValue(DataType.UWORD, ins0.arg!!.integerValue()))
-                    instructionsToReplace[index0] = ins
-                    instructionsToReplace[index1] = Instruction(Opcode.NOP)
-                }
-                Opcode.CAST_B_TO_W -> {
-                    val ins = Instruction(Opcode.PUSH_WORD, RuntimeValue(DataType.WORD, ins0.arg!!.integerValue()))
-                    instructionsToReplace[index0] = ins
-                    instructionsToReplace[index1] = Instruction(Opcode.NOP)
-                }
-                Opcode.CAST_B_TO_UW -> {
-                    val ins = Instruction(Opcode.PUSH_WORD, ins0.arg!!.cast(DataType.UWORD))
-                    instructionsToReplace[index0] = ins
-                    instructionsToReplace[index1] = Instruction(Opcode.NOP)
-                }
-                Opcode.CAST_UB_TO_W -> {
-                    val ins = Instruction(Opcode.PUSH_WORD, ins0.arg!!.cast(DataType.WORD))
-                    instructionsToReplace[index0] = ins
-                    instructionsToReplace[index1] = Instruction(Opcode.NOP)
-                }
-                Opcode.CAST_B_TO_F, Opcode.CAST_UB_TO_F -> {
-                    val ins = Instruction(Opcode.PUSH_FLOAT, RuntimeValue(DataType.FLOAT, ins0.arg!!.integerValue().toDouble()))
-                    instructionsToReplace[index0] = ins
-                    instructionsToReplace[index1] = Instruction(Opcode.NOP)
-                }
-                Opcode.CAST_W_TO_F, Opcode.CAST_UW_TO_F -> throw CompilerException("invalid conversion following a byte")
-                Opcode.DISCARD_BYTE -> {
-                    instructionsToReplace[index0] = Instruction(Opcode.NOP)
-                    instructionsToReplace[index1] = Instruction(Opcode.NOP)
-                }
-                Opcode.DISCARD_WORD, Opcode.DISCARD_FLOAT -> throw CompilerException("invalid discard type following a byte")
-                Opcode.MKWORD -> {}
-                else -> throw CompilerException("invalid conversion opcode ${ins1.opcode}")
-            }
-        }
-
-        for(blk in blocks) {
-            instructionsToReplace.clear()
-
-            val typeConversionOpcodes = setOf(
-                    Opcode.MSB,
-                    Opcode.MKWORD,
-                    Opcode.CAST_UB_TO_B,
-                    Opcode.CAST_UB_TO_UW,
-                    Opcode.CAST_UB_TO_W,
-                    Opcode.CAST_UB_TO_F,
-                    Opcode.CAST_B_TO_UB,
-                    Opcode.CAST_B_TO_UW,
-                    Opcode.CAST_B_TO_W,
-                    Opcode.CAST_B_TO_F,
-                    Opcode.CAST_UW_TO_UB,
-                    Opcode.CAST_UW_TO_B,
-                    Opcode.CAST_UW_TO_W,
-                    Opcode.CAST_UW_TO_F,
-                    Opcode.CAST_W_TO_UB,
-                    Opcode.CAST_W_TO_B,
-                    Opcode.CAST_W_TO_UW,
-                    Opcode.CAST_W_TO_F,
-                    Opcode.CAST_F_TO_UB,
-                    Opcode.CAST_F_TO_B,
-                    Opcode.CAST_F_TO_UW,
-                    Opcode.CAST_F_TO_W,
-                    Opcode.DISCARD_BYTE,
-                    Opcode.DISCARD_WORD,
-                    Opcode.DISCARD_FLOAT
-            )
-            blk.instructions.asSequence().withIndex().windowed(2).toList().forEach {
-                if (it[1].value.opcode in typeConversionOpcodes) {
-                    when (it[0].value.opcode) {
-                        Opcode.PUSH_BYTE -> optimizeByteConversion(it[0].index, it[0].value, it[1].index, it[1].value)
-                        Opcode.PUSH_WORD -> optimizeWordConversion(it[0].index, it[0].value, it[1].index, it[1].value)
-                        Opcode.PUSH_FLOAT -> optimizeFloatConversion(it[0].index, it[1].index, it[1].value)
-                        Opcode.PUSH_VAR_FLOAT,
-                        Opcode.PUSH_VAR_WORD,
-                        Opcode.PUSH_VAR_BYTE,
-                        Opcode.PUSH_MEM_B, Opcode.PUSH_MEM_UB,
-                        Opcode.PUSH_MEM_W, Opcode.PUSH_MEM_UW,
-                        Opcode.PUSH_MEM_FLOAT -> optimizeDiscardAfterPush(it[0].index, it[1].index, it[1].value)
-                        else -> {
-                        }
-                    }
-                }
-            }
-
-            for (rins in instructionsToReplace) {
-                blk.instructions[rins.key] = rins.value
-            }
-        }
-    }
-
-    fun variable(scopedname: String, decl: VarDecl) {
-        when(decl.type) {
-            VarDeclType.VAR -> {
-                // var decls that are defined inside of a StructDecl are skipped in the output
-                //   because every occurrence of the members will have a separate mangled vardecl for that occurrence
-                if(decl.parent is StructDecl)
-                    return
-
-                val valueparams = VariableParameters(decl.zeropage, decl.struct)
-                val value = when(decl.datatype) {
-                    in NumericDatatypes -> {
-                        RuntimeValue(decl.datatype, (decl.value as NumericLiteralValue).number)
-                    }
-                    in StringDatatypes -> {
-                        val litval = (decl.value as ReferenceLiteralValue)
-                        if(litval.heapId==null)
-                            throw CompilerException("string should already be in the heap")
-                        RuntimeValue(decl.datatype, heapId = litval.heapId)
-                    }
-                    in ArrayDatatypes -> {
-                        val litval = (decl.value as? ReferenceLiteralValue)
-                        if(litval!=null && litval.heapId==null)
-                            throw CompilerException("array should already be in the heap")
-                        if(litval!=null){
-                            RuntimeValue(decl.datatype, heapId = litval.heapId)
-                        } else {
-                            throw CompilerException("initialization value expected")
-                        }
-                    }
-                    DataType.STRUCT -> {
-                        // struct variables have been flattened already
-                        return
-                    }
-                    else -> throw CompilerException("weird datatype")
-                }
-                currentBlock.variables.add(Variable(scopedname, value, valueparams))
-            }
-            VarDeclType.MEMORY -> {
-                // note that constants are all folded away, but assembly code may still refer to them
-                val lv = decl.value as NumericLiteralValue
-                if(lv.type!= DataType.UWORD && lv.type!= DataType.UBYTE)
-                    throw CompilerException("expected integer memory address $lv")
-                currentBlock.memoryPointers[scopedname] = Pair(lv.number.toInt(), decl.datatype)
-            }
-            VarDeclType.CONST -> {
-                // note that constants are all folded away, but assembly code may still refer to them (if their integers)
-                // floating point constants are not generated at all!!
-                val lv = decl.value as NumericLiteralValue
-                if(lv.type in IntegerDatatypes)
-                    currentBlock.memoryPointers[scopedname] = Pair(lv.number.toInt(), decl.datatype)
-            }
-        }
-    }
-
-    fun instr(opcode: Opcode, arg: RuntimeValue? = null, arg2: RuntimeValue? = null, callLabel: String? = null, callLabel2: String? = null) {
-        currentBlock.instructions.add(Instruction(opcode, arg, arg2, callLabel, callLabel2))
-    }
-
-    fun label(labelname: String, asmProc: Boolean=false) {
-        val instr = LabelInstr(labelname, asmProc)
-        currentBlock.instructions.add(instr)
-        currentBlock.labels[labelname] = instr
-    }
-
-    fun line(position: Position) {
-        currentBlock.instructions.add(Instruction(Opcode.LINE, callLabel = "${position.line} ${position.file}"))
-    }
-
-    fun removeLastInstruction() {
-        currentBlock.instructions.removeAt(currentBlock.instructions.lastIndex)
-    }
-
-    fun memoryPointer(name: String, address: Int, datatype: DataType) {
-        currentBlock.memoryPointers[name] = Pair(address, datatype)
-    }
-
-    fun newBlock(name: String, address: Int?, options: Set<String>) {
-        currentBlock = ProgramBlock(name, address, force_output = "force_output" in options)
-        blocks.add(currentBlock)
-    }
-
-    fun writeCode(out: PrintStream, embeddedLabels: Boolean=true) {
-        out.println("; stackVM program code for '$name'")
-        writeMemory(out)
-        writeHeap(out)
-        for(blk in blocks) {
-            writeBlock(out, blk, embeddedLabels)
-        }
-    }
-
-    private fun writeHeap(out: PrintStream) {
-        out.println("%heap")
-        heap.allEntries().forEach {
-            out.print("${it.key}  ${it.value.type.name.toLowerCase()}  ")
-            when {
-                it.value.str!=null ->
-                    out.println("\"${escape(it.value.str!!)}\"")
-                it.value.array!=null -> {
-                    // this array can contain both normal integers, and pointer values
-                    val arrayvalues = it.value.array!!.map { av ->
-                        when {
-                            av.integer!=null -> av.integer.toString()
-                            av.addressOf!=null -> {
-                                if(av.addressOf.scopedname==null)
-                                    throw CompilerException("AddressOf scopedname should have been set")
-                                else
-                                    "&${av.addressOf.scopedname}"
-                            }
-                            else -> throw CompilerException("weird array value")
-                        }
-                    }
-                    out.println(arrayvalues)
-                }
-                it.value.doubleArray!=null ->
-                    out.println(it.value.doubleArray!!.toList())
-                else -> throw CompilerException("invalid heap entry $it")
-            }
-        }
-        out.println("%end_heap")
-    }
-
-    private fun writeBlock(out: PrintStream, blk: ProgramBlock, embeddedLabels: Boolean) {
-        out.println("\n%block ${blk.name} ${blk.address?.toString(16) ?: ""}")
-
-        out.println("%variables")
-        for (variable in blk.variables) {
-            if(variable.params.zp==ZeropageWish.REQUIRE_ZEROPAGE)
-                throw CompilerException("zp conflict")
-            val valuestr = variable.value.toString()
-            val struct =  if(variable.params.memberOfStruct==null) "" else "struct=${variable.params.memberOfStruct.name}"
-            out.println("${variable.scopedname}  ${variable.value.type.name.toLowerCase()}  $valuestr  zp=${variable.params.zp} s=$struct")
-        }
-        out.println("%end_variables")
-        out.println("%memorypointers")
-        for (iconst in blk.memoryPointers) {
-            out.println("${iconst.key}  ${iconst.value.second.name.toLowerCase()}  uw:${iconst.value.first.toString(16)}")
-        }
-        out.println("%end_memorypointers")
-        out.println("%instructions")
-        val labels = blk.labels.entries.associateBy({ it.value }) { it.key }
-        for (instr in blk.instructions) {
-            if (!embeddedLabels) {
-                val label = labels[instr]
-                if (label != null)
-                    out.println("$label:")
-            } else {
-                out.println(instr)
-            }
-        }
-        out.println("%end_instructions")
-
-        out.println("%end_block")
-    }
-
-    private fun writeMemory(out: PrintStream) {
-        out.println("%memory")
-        if (memory.isNotEmpty())
-            TODO("add support for writing/reading initial memory values")
-        out.println("%end_memory")
-    }
-}

DeprecatedStackVm/src/compiler/intermediate/Opcode.kt

@@ -1,291 +0,0 @@
-package compiler.intermediate
-
-enum class Opcode {
-
-    // pushing values on the (evaluation) stack
-    PUSH_BYTE,       // push byte value
-    PUSH_WORD,       // push word value   (or 'address' of string / array)
-    PUSH_FLOAT,      // push float value
-    PUSH_MEM_B,      // push byte value from memory to stack
-    PUSH_MEM_UB,     // push unsigned byte value from memory to stack
-    PUSH_MEM_W,      // push word value from memory to stack
-    PUSH_MEM_UW,     // push unsigned word value from memory to stack
-    PUSH_MEM_FLOAT,  // push float value from memory to stack
-    PUSH_MEMREAD,    // push memory value from address that's on the stack
-    PUSH_VAR_BYTE,   // push byte variable (ubyte, byte)
-    PUSH_VAR_WORD,   // push word variable (uword, word)
-    PUSH_VAR_FLOAT,  // push float variable
-    PUSH_REGAX_WORD, // push registers A/X as a 16-bit word
-    PUSH_REGAY_WORD, // push registers A/Y as a 16-bit word
-    PUSH_REGXY_WORD, // push registers X/Y as a 16-bit word
-    PUSH_ADDR_HEAPVAR,  // push the address of the variable that's on the heap (string or array)
-    DUP_B,          // duplicate the top byte on the stack
-    DUP_W,          // duplicate the top word on the stack
-
-    // popping values off the (evaluation) stack, possibly storing them in another location
-    DISCARD_BYTE,    // discard top byte value
-    DISCARD_WORD,    // discard top word value
-    DISCARD_FLOAT,   // discard top float value
-    POP_MEM_BYTE,    // pop (u)byte value into destination memory address
-    POP_MEM_WORD,    // pop (u)word value into destination memory address
-    POP_MEM_FLOAT,   // pop float value into destination memory address
-    POP_MEMWRITE,    // pop address and byte stack and write the byte to the memory address
-    POP_VAR_BYTE,    // pop (u)byte value into variable
-    POP_VAR_WORD,    // pop (u)word value into variable
-    POP_VAR_FLOAT,   // pop float value into variable
-    POP_REGAX_WORD,  // pop uword from stack into A/X registers
-    POP_REGAY_WORD,  // pop uword from stack into A/Y registers
-    POP_REGXY_WORD,  // pop uword from stack into X/Y registers
-
-    // numeric arithmetic
-    ADD_UB,
-    ADD_B,
-    ADD_UW,
-    ADD_W,
-    ADD_F,
-    SUB_UB,
-    SUB_B,
-    SUB_UW,
-    SUB_W,
-    SUB_F,
-    MUL_UB,
-    MUL_B,
-    MUL_UW,
-    MUL_W,
-    MUL_F,
-    IDIV_UB,
-    IDIV_B,
-    IDIV_UW,
-    IDIV_W,
-    DIV_F,
-    REMAINDER_UB,   // signed remainder is undefined/unimplemented
-    REMAINDER_UW,   // signed remainder is undefined/unimplemented
-    POW_F,
-    NEG_B,
-    NEG_W,
-    NEG_F,
-    ABS_B,
-    ABS_W,
-    ABS_F,
-
-    // bit shifts and bitwise arithmetic
-    SHIFTEDL_BYTE,      // shifts stack value rather than in-place mem/var
-    SHIFTEDL_WORD,      // shifts stack value rather than in-place mem/var
-    SHIFTEDR_UBYTE,     // shifts stack value rather than in-place mem/var
-    SHIFTEDR_SBYTE,     // shifts stack value rather than in-place mem/var
-    SHIFTEDR_UWORD,     // shifts stack value rather than in-place mem/var
-    SHIFTEDR_SWORD,     // shifts stack value rather than in-place mem/var
-    SHL_BYTE,
-    SHL_WORD,
-    SHL_MEM_BYTE,
-    SHL_MEM_WORD,
-    SHL_VAR_BYTE,
-    SHL_VAR_WORD,
-    SHR_UBYTE,
-    SHR_SBYTE,
-    SHR_UWORD,
-    SHR_SWORD,
-    SHR_MEM_UBYTE,
-    SHR_MEM_SBYTE,
-    SHR_MEM_UWORD,
-    SHR_MEM_SWORD,
-    SHR_VAR_UBYTE,
-    SHR_VAR_SBYTE,
-    SHR_VAR_UWORD,
-    SHR_VAR_SWORD,
-    ROL_BYTE,
-    ROL_WORD,
-    ROL_MEM_BYTE,
-    ROL_MEM_WORD,
-    ROL_VAR_BYTE,
-    ROL_VAR_WORD,
-    ROR_BYTE,
-    ROR_WORD,
-    ROR_MEM_BYTE,
-    ROR_MEM_WORD,
-    ROR_VAR_BYTE,
-    ROR_VAR_WORD,
-    ROL2_BYTE,
-    ROL2_WORD,
-    ROL2_MEM_BYTE,
-    ROL2_MEM_WORD,
-    ROL2_VAR_BYTE,
-    ROL2_VAR_WORD,
-    ROR2_BYTE,
-    ROR2_WORD,
-    ROR2_MEM_BYTE,
-    ROR2_MEM_WORD,
-    ROR2_VAR_BYTE,
-    ROR2_VAR_WORD,
-    BITAND_BYTE,
-    BITAND_WORD,
-    BITOR_BYTE,
-    BITOR_WORD,
-    BITXOR_BYTE,
-    BITXOR_WORD,
-    INV_BYTE,
-    INV_WORD,
-
-    // numeric type conversions
-    MSB,        // note: lsb is equivalent to  CAST_UW_TO_UB  or CAST_W_TO_UB
-    MKWORD,        // create a word from lsb + msb
-    CAST_UB_TO_B,
-    CAST_UB_TO_UW,
-    CAST_UB_TO_W,
-    CAST_UB_TO_F,
-    CAST_B_TO_UB,
-    CAST_B_TO_UW,
-    CAST_B_TO_W,
-    CAST_B_TO_F,
-    CAST_W_TO_UB,
-    CAST_W_TO_B,
-    CAST_W_TO_UW,
-    CAST_W_TO_F,
-    CAST_UW_TO_UB,
-    CAST_UW_TO_B,
-    CAST_UW_TO_W,
-    CAST_UW_TO_F,
-    CAST_F_TO_UB,
-    CAST_F_TO_B,
-    CAST_F_TO_UW,
-    CAST_F_TO_W,
-
-    // logical operations
-    AND_BYTE,
-    AND_WORD,
-    OR_BYTE,
-    OR_WORD,
-    XOR_BYTE,
-    XOR_WORD,
-    NOT_BYTE,
-    NOT_WORD,
-
-    // increment, decrement
-    INC_VAR_B,
-    INC_VAR_UB,
-    INC_VAR_W,
-    INC_VAR_UW,
-    INC_VAR_F,
-    DEC_VAR_B,
-    DEC_VAR_UB,
-    DEC_VAR_W,
-    DEC_VAR_UW,
-    DEC_VAR_F,
-    INC_MEMORY,             // increment direct address
-    DEC_MEMORY,             // decrement direct address
-    POP_INC_MEMORY,         // increment address from stack
-    POP_DEC_MEMORY,         // decrement address from address
-
-    // comparisons
-    LESS_B,
-    LESS_UB,
-    LESS_W,
-    LESS_UW,
-    LESS_F,
-    GREATER_B,
-    GREATER_UB,
-    GREATER_W,
-    GREATER_UW,
-    GREATER_F,
-    LESSEQ_B,
-    LESSEQ_UB,
-    LESSEQ_W,
-    LESSEQ_UW,
-    LESSEQ_F,
-    GREATEREQ_B,
-    GREATEREQ_UB,
-    GREATEREQ_W,
-    GREATEREQ_UW,
-    GREATEREQ_F,
-    EQUAL_BYTE,
-    EQUAL_WORD,
-    EQUAL_F,
-    NOTEQUAL_BYTE,
-    NOTEQUAL_WORD,
-    NOTEQUAL_F,
-    CMP_B,          // sets processor status flags based on comparison, instead of pushing a result value
-    CMP_UB,         // sets processor status flags based on comparison, instead of pushing a result value
-    CMP_W,          // sets processor status flags based on comparison, instead of pushing a result value
-    CMP_UW,         // sets processor status flags based on comparison, instead of pushing a result value
-
-    // array access and simple manipulations
-    READ_INDEXED_VAR_BYTE,
-    READ_INDEXED_VAR_WORD,
-    READ_INDEXED_VAR_FLOAT,
-    WRITE_INDEXED_VAR_BYTE,
-    WRITE_INDEXED_VAR_WORD,
-    WRITE_INDEXED_VAR_FLOAT,
-    INC_INDEXED_VAR_B,
-    INC_INDEXED_VAR_UB,
-    INC_INDEXED_VAR_W,
-    INC_INDEXED_VAR_UW,
-    INC_INDEXED_VAR_FLOAT,
-    DEC_INDEXED_VAR_B,
-    DEC_INDEXED_VAR_UB,
-    DEC_INDEXED_VAR_W,
-    DEC_INDEXED_VAR_UW,
-    DEC_INDEXED_VAR_FLOAT,
-
-    // branching, without consuming a value from the stack
-    JUMP,
-    BCS,       // branch if carry set
-    BCC,       // branch if carry clear
-    BZ,        // branch if zero flag
-    BNZ,       // branch if not zero flag
-    BNEG,      // branch if negative flag
-    BPOS,      // branch if not negative flag
-    BVS,       // branch if overflow flag
-    BVC,       // branch if not overflow flag
-    // branching, based on value on the stack (which is consumed)
-    JZ,         // branch if value is zero (byte)
-    JNZ,        // branch if value is not zero (byte)
-    JZW,         // branch if value is zero (word)
-    JNZW,        // branch if value is not zero (word)
-
-    // subroutines
-    CALL,
-    RETURN,
-    SYSCALL,
-    START_PROCDEF,
-    END_PROCDEF,
-
-    // misc
-    SEC,        // set carry status flag  NOTE: is mostly fake, carry flag is not affected by any numeric operations
-    CLC,        // clear carry status flag  NOTE: is mostly fake, carry flag is not affected by any numeric operations
-    SEI,        // set irq-disable status flag
-    CLI,        // clear irq-disable status flag
-    CARRY_TO_A, // load var/register A with carry status bit
-    RSAVE,      // save all internal registers and status flags
-    RSAVEX,     // save just X (the evaluation stack pointer)
-    RRESTORE,   // restore all internal registers and status flags
-    RRESTOREX,  // restore just X (the evaluation stack pointer)
-
-    NOP,        // do nothing
-    BREAKPOINT, // breakpoint
-    TERMINATE,  // end the program
-    LINE,       // track source file line number
-    INLINE_ASSEMBLY,        // container to hold inline raw assembly code
-    INCLUDE_FILE            // directive to include a file at this position in the memory of the program
-}
-
-val opcodesWithVarArgument = setOf(
-        Opcode.INC_VAR_B, Opcode.INC_VAR_W, Opcode.DEC_VAR_B, Opcode.DEC_VAR_W,
-        Opcode.INC_VAR_UB, Opcode.INC_VAR_UW, Opcode.DEC_VAR_UB, Opcode.DEC_VAR_UW,
-        Opcode.SHR_VAR_SBYTE, Opcode.SHR_VAR_UBYTE, Opcode.SHR_VAR_SWORD, Opcode.SHR_VAR_UWORD,
-        Opcode.SHL_VAR_BYTE, Opcode.SHL_VAR_WORD,
-        Opcode.ROL_VAR_BYTE, Opcode.ROL_VAR_WORD, Opcode.ROR_VAR_BYTE, Opcode.ROR_VAR_WORD,
-        Opcode.ROL2_VAR_BYTE, Opcode.ROL2_VAR_WORD, Opcode.ROR2_VAR_BYTE, Opcode.ROR2_VAR_WORD,
-        Opcode.POP_VAR_BYTE, Opcode.POP_VAR_WORD, Opcode.POP_VAR_FLOAT,
-        Opcode.PUSH_VAR_BYTE, Opcode.PUSH_VAR_WORD, Opcode.PUSH_VAR_FLOAT, Opcode.PUSH_ADDR_HEAPVAR,
-        Opcode.READ_INDEXED_VAR_BYTE, Opcode.READ_INDEXED_VAR_WORD, Opcode.READ_INDEXED_VAR_FLOAT,
-        Opcode.WRITE_INDEXED_VAR_BYTE, Opcode.WRITE_INDEXED_VAR_WORD, Opcode.WRITE_INDEXED_VAR_FLOAT,
-        Opcode.INC_INDEXED_VAR_UB, Opcode.INC_INDEXED_VAR_B, Opcode.INC_INDEXED_VAR_UW,
-        Opcode.INC_INDEXED_VAR_W, Opcode.INC_INDEXED_VAR_FLOAT,
-        Opcode.DEC_INDEXED_VAR_UB, Opcode.DEC_INDEXED_VAR_B, Opcode.DEC_INDEXED_VAR_UW,
-        Opcode.DEC_INDEXED_VAR_W, Opcode.DEC_INDEXED_VAR_FLOAT
-)
-
-val branchOpcodes = setOf(
-        Opcode.BCS, Opcode.BCC, Opcode.BZ, Opcode.BNZ,
-        Opcode.BNEG, Opcode.BPOS, Opcode.BVS, Opcode.BVC
-)

DeprecatedStackVm/src/compiler/target/c64/codegen/AsmGen.kt

@@ -1,761 +0,0 @@
-package compiler.target.c64.codegen
-
-// note: to put stuff on the stack, we use Absolute,X  addressing mode which is 3 bytes / 4 cycles
-// possible space optimization is to use zeropage (indirect),Y  which is 2 bytes, but 5 cycles
-
-import prog8.ast.antlr.escape
-import prog8.ast.base.DataType
-import prog8.ast.base.initvarsSubName
-import prog8.ast.statements.ZeropageWish
-import prog8.compiler.*
-import prog8.compiler.intermediate.Instruction
-import prog8.compiler.intermediate.IntermediateProgram
-import prog8.compiler.intermediate.LabelInstr
-import prog8.compiler.intermediate.Opcode
-import prog8.compiler.target.c64.AssemblyProgram
-import prog8.compiler.target.c64.MachineDefinition
-import prog8.compiler.target.c64.Petscii
-import prog8.vm.RuntimeValue
-import java.io.File
-import java.util.*
-import kotlin.math.abs
-
-
-class AssemblyError(msg: String) : RuntimeException(msg)
-
-
-
-internal fun intVal(valueInstr: Instruction) = valueInstr.arg!!.integerValue()
-internal fun hexVal(valueInstr: Instruction) = valueInstr.arg!!.integerValue().toHex()
-internal fun hexValPlusOne(valueInstr: Instruction) = (valueInstr.arg!!.integerValue()+1).toHex()
-internal fun getFloatConst(value: RuntimeValue): String =
-        globalFloatConsts[value.numericValue().toDouble()]
-                ?: throw AssemblyError("should have a global float const for number $value")
-
-internal val globalFloatConsts = mutableMapOf<Double, String>()
-
-internal fun signExtendA(into: String) =
-        """
-        ora  #$7f
-        bmi  +
-        lda  #0
-+       sta  $into
-        """
-
-class AsmGen(private val options: CompilationOptions, private val program: IntermediateProgram,
-             private val heap: HeapValues, private val zeropage: Zeropage) {
-    private val assemblyLines = mutableListOf<String>()
-    private lateinit var block: IntermediateProgram.ProgramBlock
-
-    init {
-        // Convert invalid label names (such as "<anon-1>") to something that's allowed.
-        val newblocks = mutableListOf<IntermediateProgram.ProgramBlock>()
-        for(block in program.blocks) {
-            val newvars = block.variables.map { IntermediateProgram.Variable(symname(it.scopedname, block), it.value, it.params) }.toMutableList()
-            val newlabels = block.labels.map { symname(it.key, block) to it.value}.toMap().toMutableMap()
-            val newinstructions = block.instructions.asSequence().map {
-                when {
-                    it is LabelInstr -> LabelInstr(symname(it.name, block), it.asmProc)
-                    it.opcode == Opcode.INLINE_ASSEMBLY -> it
-                    else ->
-                        Instruction(it.opcode, it.arg, it.arg2,
-                            callLabel = if (it.callLabel != null) symname(it.callLabel, block) else null,
-                            callLabel2 = if (it.callLabel2 != null) symname(it.callLabel2, block) else null)
-                }
-            }.toMutableList()
-            val newMempointers = block.memoryPointers.map { symname(it.key, block) to it.value }.toMap().toMutableMap()
-            val newblock = IntermediateProgram.ProgramBlock(
-                    block.name,
-                    block.address,
-                    newinstructions,
-                    newvars,
-                    newMempointers,
-                    newlabels,
-                    force_output = block.force_output)
-            newblocks.add(newblock)
-        }
-        program.blocks.clear()
-        program.blocks.addAll(newblocks)
-
-        val newAllocatedZp = program.allocatedZeropageVariables.map { symname(it.key, null) to it.value}
-        program.allocatedZeropageVariables.clear()
-        program.allocatedZeropageVariables.putAll(newAllocatedZp)
-
-        // make a list of all const floats that are used
-        for(block in program.blocks) {
-            for(ins in block.instructions.filter{it.arg?.type== DataType.FLOAT}) {
-                val float = ins.arg!!.numericValue().toDouble()
-                if(float !in globalFloatConsts)
-                    globalFloatConsts[float] = "prog8_const_float_${globalFloatConsts.size}"
-            }
-        }
-    }
-
-    fun compileToAssembly(optimize: Boolean): AssemblyProgram {
-        println("Generating assembly code from intermediate code... ")
-
-        assemblyLines.clear()
-        header()
-        for(b in program.blocks)
-            block2asm(b)
-
-        if(optimize) {
-            var optimizationsDone = 1
-            while (optimizationsDone > 0) {
-                optimizationsDone = optimizeAssembly(assemblyLines)
-            }
-        }
-
-        File("${program.name}.asm").printWriter().use {
-            for (line in assemblyLines) { it.println(line) }
-        }
-
-        return AssemblyProgram(program.name)
-    }
-
-    private fun out(str: String, splitlines: Boolean=true) {
-        if(splitlines) {
-            for (line in str.split('\n')) {
-                val trimmed = if (line.startsWith(' ')) "\t" + line.trim() else line.trim()
-                // trimmed = trimmed.replace(Regex("^\\+\\s+"), "+\t")  // sanitize local label indentation
-                assemblyLines.add(trimmed)
-            }
-        } else assemblyLines.add(str)
-    }
-
-
-    // convert a fully scoped name (defined in the given block) to a valid assembly symbol name
-    private fun symname(scoped: String, block: IntermediateProgram.ProgramBlock?): String {
-        if(' ' in scoped)
-            return scoped
-        val blockLocal: Boolean
-        var name = if (block!=null && scoped.startsWith("${block.name}.")) {
-            blockLocal = true
-            scoped.substring(block.name.length+1)
-        }
-        else {
-            blockLocal = false
-            scoped
-        }
-        name = name.replace("<", "prog8_").replace(">", "")     // take care of the autogenerated invalid (anon) label names
-        if(name=="-")
-            return "-"
-        if(blockLocal)
-            name = name.replace(".", "_")
-        else {
-            val parts = name.split(".", limit=2)
-            if(parts.size>1)
-                name = "${parts[0]}.${parts[1].replace(".", "_")}"
-        }
-        return name.replace("-", "")
-    }
-
-    private fun makeFloatFill(flt: MachineDefinition.Mflpt5): String {
-        val b0 = "$"+flt.b0.toString(16).padStart(2, '0')
-        val b1 = "$"+flt.b1.toString(16).padStart(2, '0')
-        val b2 = "$"+flt.b2.toString(16).padStart(2, '0')
-        val b3 = "$"+flt.b3.toString(16).padStart(2, '0')
-        val b4 = "$"+flt.b4.toString(16).padStart(2, '0')
-        return "$b0, $b1, $b2, $b3, $b4"
-    }
-
-    private fun header() {
-        val ourName = this.javaClass.name
-        out("; 6502 assembly code for '${program.name}'")
-        out("; generated by $ourName on ${Date()}")
-        out("; assembler syntax is for the 64tasm cross-assembler")
-        out("; output options: output=${options.output} launcher=${options.launcher} zp=${options.zeropage}")
-        out("\n.cpu  '6502'\n.enc  'none'\n")
-
-        if(program.loadAddress==0)   // fix load address
-            program.loadAddress = if(options.launcher==LauncherType.BASIC)
-                MachineDefinition.BASIC_LOAD_ADDRESS else MachineDefinition.RAW_LOAD_ADDRESS
-
-        when {
-            options.launcher == LauncherType.BASIC -> {
-                if (program.loadAddress != 0x0801)
-                    throw AssemblyError("BASIC output must have load address $0801")
-                out("; ---- basic program with sys call ----")
-                out("* = ${program.loadAddress.toHex()}")
-                val year = Calendar.getInstance().get(Calendar.YEAR)
-                out("  .word  (+), $year")
-                out("  .null  $9e, format(' %d ', _prog8_entrypoint), $3a, $8f, ' prog8 by idj'")
-                out("+\t.word  0")
-                out("_prog8_entrypoint\t; assembly code starts here\n")
-                out("  jsr  prog8_lib.init_system")
-            }
-            options.output == OutputType.PRG -> {
-                out("; ---- program without basic sys call ----")
-                out("* = ${program.loadAddress.toHex()}\n")
-                out("  jsr  prog8_lib.init_system")
-            }
-            options.output == OutputType.RAW -> {
-                out("; ---- raw assembler program ----")
-                out("* = ${program.loadAddress.toHex()}\n")
-            }
-        }
-
-        if(zeropage.exitProgramStrategy!=Zeropage.ExitProgramStrategy.CLEAN_EXIT) {
-            // disable shift-commodore charset switching and run/stop key
-            out("  lda  #$80")
-            out("  lda  #$80")
-            out("  sta  657\t; disable charset switching")
-            out("  lda  #239")
-            out("  sta  808\t; disable run/stop key")
-        }
-
-        out("  ldx  #\$ff\t; init estack pointer")
-        out("  ; initialize the variables in each block")
-        for(block in program.blocks) {
-            val initVarsLabel = block.instructions.firstOrNull { it is LabelInstr && it.name== initvarsSubName } as? LabelInstr
-            if(initVarsLabel!=null)
-                out("  jsr  ${block.name}.${initVarsLabel.name}")
-        }
-        out("  clc")
-        when(zeropage.exitProgramStrategy) {
-            Zeropage.ExitProgramStrategy.CLEAN_EXIT -> {
-                out("  jmp  main.start\t; jump to program entrypoint")
-            }
-            Zeropage.ExitProgramStrategy.SYSTEM_RESET -> {
-                out("  jsr  main.start\t; call program entrypoint")
-                out("  jmp  (c64.RESET_VEC)\t; cold reset")
-            }
-        }
-        out("")
-
-        // the global list of all floating point constants for the whole program
-        for(flt in globalFloatConsts) {
-            val floatFill = makeFloatFill(MachineDefinition.Mflpt5.fromNumber(flt.key))
-            out("${flt.value}\t.byte  $floatFill  ; float ${flt.key}")
-        }
-    }
-
-    private fun block2asm(blk: IntermediateProgram.ProgramBlock) {
-        block = blk
-        out("\n; ---- block: '${block.name}' ----")
-        if(!blk.force_output)
-            out("${block.name}\t.proc\n")
-        if(block.address!=null) {
-            out(".cerror * > ${block.address?.toHex()}, 'block address overlaps by ', *-${block.address?.toHex()},' bytes'")
-            out("* = ${block.address?.toHex()}")
-        }
-
-        // deal with zeropage variables
-        for(variable in blk.variables) {
-            val sym = symname(blk.name+"."+variable.scopedname, null)
-            val zpVar = program.allocatedZeropageVariables[sym]
-            if(zpVar==null) {
-                // This var is not on the ZP yet. Attempt to move it there (if it's not a float, those take up too much space)
-                if(variable.params.zp != ZeropageWish.NOT_IN_ZEROPAGE &&
-                        variable.value.type in zeropage.allowedDatatypes
-                        && variable.value.type != DataType.FLOAT) {
-                    try {
-                        val address = zeropage.allocate(sym, variable.value.type, null)
-                        out("${variable.scopedname} = $address\t; auto zp ${variable.value.type}")
-                        // make sure we add the var to the set of zpvars for this block
-                        program.allocatedZeropageVariables[sym] = Pair(address, variable.value.type)
-                    } catch (x: ZeropageDepletedError) {
-                        // leave it as it is.
-                    }
-                }
-            }
-            else {
-                // it was already allocated on the zp
-                out("${variable.scopedname} = ${zpVar.first}\t; zp ${zpVar.second}")
-            }
-        }
-
-        out("\n; memdefs and kernel subroutines")
-        memdefs2asm(block)
-        out("\n; non-zeropage variables")
-        vardecls2asm(block)
-        out("")
-
-        val instructionPatternWindowSize = 8        // increase once patterns occur longer than this.
-        var processed = 0
-
-        for (ins in block.instructions.windowed(instructionPatternWindowSize, partialWindows = true)) {
-            if (processed == 0) {
-                processed = instr2asm(ins)
-                if (processed == 0) {
-                    // the instructions are not recognised yet and can't be translated into assembly
-                    throw CompilerException("no asm translation found for instruction pattern: $ins")
-                }
-            }
-            processed--
-        }
-        if(!blk.force_output)
-            out("\n\t.pend\n")
-    }
-
-    private fun memdefs2asm(block: IntermediateProgram.ProgramBlock) {
-        for(m in block.memoryPointers) {
-            out("  ${m.key} = ${m.value.first.toHex()}")
-        }
-    }
-
-    private fun vardecls2asm(block: IntermediateProgram.ProgramBlock) {
-        val uniqueNames = block.variables.map { it.scopedname }.toSet()
-        if (uniqueNames.size != block.variables.size)
-            throw AssemblyError("not all variables have unique names")
-
-        // these are the non-zeropage variables.
-        // first get all the flattened struct members, they MUST remain in order
-        out(";  flattened struct members")
-        val (structMembers, normalVars) = block.variables.partition { it.params.memberOfStruct!=null }
-        structMembers.forEach { vardecl2asm(it.scopedname, it.value, it.params) }
-
-        // sort the other variables by type
-        out(";  other variables sorted by type")
-        val sortedVars = normalVars.sortedBy { it.value.type }
-        for (variable in sortedVars) {
-            val sym = symname(block.name + "." + variable.scopedname, null)
-            if(sym in program.allocatedZeropageVariables)
-                continue  // skip the ones that already belong in the zero page
-            vardecl2asm(variable.scopedname, variable.value, variable.params)
-        }
-    }
-
-    private fun vardecl2asm(varname: String, value: RuntimeValue, parameters: IntermediateProgram.VariableParameters) {
-        when (value.type) {
-            DataType.UBYTE -> out("$varname\t.byte  0")
-            DataType.BYTE -> out("$varname\t.char  0")
-            DataType.UWORD -> out("$varname\t.word  0")
-            DataType.WORD -> out("$varname\t.sint  0")
-            DataType.FLOAT -> out("$varname\t.byte  0,0,0,0,0  ; float")
-            DataType.STR, DataType.STR_S -> {
-                val rawStr = heap.get(value.heapId!!).str!!
-                val bytes = encodeStr(rawStr, value.type).map { "$" + it.toString(16).padStart(2, '0') }
-                out("$varname\t; ${value.type} \"${escape(rawStr).replace("\u0000", "<NULL>")}\"")
-                for (chunk in bytes.chunked(16))
-                    out("  .byte  " + chunk.joinToString())
-            }
-            DataType.ARRAY_UB -> {
-                // unsigned integer byte arraysize
-                val data = makeArrayFillDataUnsigned(value)
-                if (data.size <= 16)
-                    out("$varname\t.byte  ${data.joinToString()}")
-                else {
-                    out(varname)
-                    for (chunk in data.chunked(16))
-                        out("  .byte  " + chunk.joinToString())
-                }
-            }
-            DataType.ARRAY_B -> {
-                // signed integer byte arraysize
-                val data = makeArrayFillDataSigned(value)
-                if (data.size <= 16)
-                    out("$varname\t.char  ${data.joinToString()}")
-                else {
-                    out(varname)
-                    for (chunk in data.chunked(16))
-                        out("  .char  " + chunk.joinToString())
-                }
-            }
-            DataType.ARRAY_UW -> {
-                // unsigned word arraysize
-                val data = makeArrayFillDataUnsigned(value)
-                if (data.size <= 16)
-                    out("$varname\t.word  ${data.joinToString()}")
-                else {
-                    out(varname)
-                    for (chunk in data.chunked(16))
-                        out("  .word  " + chunk.joinToString())
-                }
-            }
-            DataType.ARRAY_W -> {
-                // signed word arraysize
-                val data = makeArrayFillDataSigned(value)
-                if (data.size <= 16)
-                    out("$varname\t.sint  ${data.joinToString()}")
-                else {
-                    out(varname)
-                    for (chunk in data.chunked(16))
-                        out("  .sint  " + chunk.joinToString())
-                }
-            }
-            DataType.ARRAY_F -> {
-                // float arraysize
-                val array = heap.get(value.heapId!!).doubleArray!!
-                val floatFills = array.map { makeFloatFill(MachineDefinition.Mflpt5.fromNumber(it)) }
-                out(varname)
-                for (f in array.zip(floatFills))
-                    out("  .byte  ${f.second}  ; float ${f.first}")
-            }
-            DataType.STRUCT -> throw AssemblyError("vars of type STRUCT should have been removed because flattened")
-        }
-    }
-
-
-    private fun encodeStr(str: String, dt: DataType): List<Short> {
-        return when(dt) {
-            DataType.STR -> {
-                val bytes = Petscii.encodePetscii(str, true)
-                bytes.plus(0)
-            }
-            DataType.STR_S -> {
-                val bytes = Petscii.encodeScreencode(str, true)
-                bytes.plus(0)
-            }
-            else -> throw AssemblyError("invalid str type")
-        }
-    }
-
-    private fun makeArrayFillDataUnsigned(value: RuntimeValue): List<String> {
-        val array = heap.get(value.heapId!!).array!!
-        return when {
-            value.type== DataType.ARRAY_UB ->
-                // byte array can never contain pointer-to types, so treat values as all integers
-                array.map { "$"+it.integer!!.toString(16).padStart(2, '0') }
-            value.type== DataType.ARRAY_UW -> array.map {
-                when {
-                    it.integer!=null -> "$"+it.integer.toString(16).padStart(2, '0')
-                    it.addressOf!=null -> symname(it.addressOf.scopedname!!, block)
-                    else -> throw AssemblyError("weird type in array")
-                }
-            }
-            else -> throw AssemblyError("invalid arraysize type")
-        }
-    }
-
-    private fun makeArrayFillDataSigned(value: RuntimeValue): List<String> {
-        val array = heap.get(value.heapId!!).array!!
-        // note: array of signed value can never contain pointer-to type, so simply accept values as being all integers
-        return if (value.type == DataType.ARRAY_B || value.type == DataType.ARRAY_W) {
-            array.map {
-                if(it.integer!!>=0)
-                    "$"+it.integer.toString(16).padStart(2, '0')
-                else
-                    "-$"+abs(it.integer).toString(16).padStart(2, '0')
-            }
-        }
-        else throw AssemblyError("invalid arraysize type")
-    }
-
-    private fun instr2asm(ins: List<Instruction>): Int {
-        // find best patterns (matching the most of the lines, then with the smallest weight)
-        val fragments = findPatterns(ins).sortedByDescending { it.segmentSize }
-        if(fragments.isEmpty()) {
-            // we didn't find any matching patterns (complex multi-instruction fragments), try simple ones
-            val firstIns = ins[0]
-            val singleAsm = simpleInstr2Asm(firstIns, block)
-            if(singleAsm != null) {
-                outputAsmFragment(singleAsm)
-                return 1
-            }
-            return 0
-        }
-        val best = fragments[0]
-        outputAsmFragment(best.asm)
-        return best.segmentSize
-    }
-
-    private fun outputAsmFragment(singleAsm: String) {
-        if (singleAsm.isNotEmpty()) {
-            if(singleAsm.startsWith("@inline@"))
-                out(singleAsm.substring(8), false)
-            else {
-                val withNewlines = singleAsm.replace('|', '\n')
-                out(withNewlines)
-            }
-        }
-    }
-
-    private fun findPatterns(segment: List<Instruction>): List<AsmFragment> {
-        val opcodes = segment.map { it.opcode }
-        val result = mutableListOf<AsmFragment>()
-
-        // check for operations that modify a single value, by putting it on the stack (and popping it afterwards)
-        if((opcodes[0]==Opcode.PUSH_VAR_BYTE && opcodes[2]==Opcode.POP_VAR_BYTE) ||
-                (opcodes[0]==Opcode.PUSH_VAR_WORD && opcodes[2]==Opcode.POP_VAR_WORD) ||
-                (opcodes[0]==Opcode.PUSH_VAR_FLOAT && opcodes[2]==Opcode.POP_VAR_FLOAT)) {
-            if (segment[0].callLabel == segment[2].callLabel) {
-                val fragment = sameVarOperation(segment[0].callLabel!!, segment[1])
-                if (fragment != null) {
-                    fragment.segmentSize = 3
-                    result.add(fragment)
-                }
-            }
-        }
-        else if((opcodes[0]==Opcode.PUSH_BYTE && opcodes[1] in setOf(Opcode.INC_INDEXED_VAR_B, Opcode.INC_INDEXED_VAR_UB,
-                        Opcode.INC_INDEXED_VAR_UW, Opcode.INC_INDEXED_VAR_W, Opcode.INC_INDEXED_VAR_FLOAT,
-                        Opcode.DEC_INDEXED_VAR_B, Opcode.DEC_INDEXED_VAR_UB, Opcode.DEC_INDEXED_VAR_W,
-                        Opcode.DEC_INDEXED_VAR_UW, Opcode.DEC_INDEXED_VAR_FLOAT))) {
-            val fragment = sameConstantIndexedVarOperation(segment[1].callLabel!!, segment[0].arg!!.integerValue(), segment[1])
-            if(fragment!=null) {
-                fragment.segmentSize=2
-                result.add(fragment)
-            }
-        }
-        else if((opcodes[0]==Opcode.PUSH_VAR_BYTE && opcodes[1] in setOf(Opcode.INC_INDEXED_VAR_B, Opcode.INC_INDEXED_VAR_UB,
-                        Opcode.INC_INDEXED_VAR_UW, Opcode.INC_INDEXED_VAR_W, Opcode.INC_INDEXED_VAR_FLOAT,
-                        Opcode.DEC_INDEXED_VAR_B, Opcode.DEC_INDEXED_VAR_UB, Opcode.DEC_INDEXED_VAR_W,
-                        Opcode.DEC_INDEXED_VAR_UW, Opcode.DEC_INDEXED_VAR_FLOAT))) {
-            val fragment = sameIndexedVarOperation(segment[1].callLabel!!, segment[0].callLabel!!, segment[1])
-            if(fragment!=null) {
-                fragment.segmentSize=2
-                result.add(fragment)
-            }
-        }
-        else if((opcodes[0]==Opcode.PUSH_MEM_UB && opcodes[2]==Opcode.POP_MEM_BYTE) ||
-                (opcodes[0]==Opcode.PUSH_MEM_B && opcodes[2]==Opcode.POP_MEM_BYTE) ||
-                (opcodes[0]==Opcode.PUSH_MEM_UW && opcodes[2]==Opcode.POP_MEM_WORD) ||
-                (opcodes[0]==Opcode.PUSH_MEM_W && opcodes[2]==Opcode.POP_MEM_WORD) ||
-                (opcodes[0]==Opcode.PUSH_MEM_FLOAT && opcodes[2]==Opcode.POP_MEM_FLOAT)) {
-            if(segment[0].arg==segment[2].arg) {
-                val fragment = sameMemOperation(segment[0].arg!!.integerValue(), segment[1])
-                if(fragment!=null) {
-                    fragment.segmentSize = 3
-                    result.add(fragment)
-                }
-            }
-        }
-        else if((opcodes[0]==Opcode.PUSH_BYTE && opcodes[1]==Opcode.READ_INDEXED_VAR_BYTE &&
-                        opcodes[3]==Opcode.PUSH_BYTE && opcodes[4]==Opcode.WRITE_INDEXED_VAR_BYTE) ||
-                (opcodes[0]==Opcode.PUSH_BYTE && opcodes[1]==Opcode.READ_INDEXED_VAR_WORD &&
-                        opcodes[3]==Opcode.PUSH_BYTE && opcodes[4]==Opcode.WRITE_INDEXED_VAR_WORD)) {
-            if(segment[0].arg==segment[3].arg && segment[1].callLabel==segment[4].callLabel) {
-                val fragment = sameConstantIndexedVarOperation(segment[1].callLabel!!, segment[0].arg!!.integerValue(), segment[2])
-                if(fragment!=null){
-                    fragment.segmentSize = 5
-                    result.add(fragment)
-                }
-            }
-        }
-        else if((opcodes[0]==Opcode.PUSH_VAR_BYTE && opcodes[1]==Opcode.READ_INDEXED_VAR_BYTE &&
-                        opcodes[3]==Opcode.PUSH_VAR_BYTE && opcodes[4]==Opcode.WRITE_INDEXED_VAR_BYTE) ||
-                (opcodes[0]==Opcode.PUSH_VAR_BYTE && opcodes[1]==Opcode.READ_INDEXED_VAR_WORD &&
-                        opcodes[3]==Opcode.PUSH_VAR_BYTE && opcodes[4]==Opcode.WRITE_INDEXED_VAR_WORD)) {
-            if(segment[0].callLabel==segment[3].callLabel && segment[1].callLabel==segment[4].callLabel) {
-                val fragment = sameIndexedVarOperation(segment[1].callLabel!!, segment[0].callLabel!!, segment[2])
-                if(fragment!=null){
-                    fragment.segmentSize = 5
-                    result.add(fragment)
-                }
-            }
-        }
-
-        // add any matching patterns from the big list
-        for(pattern in Patterns.patterns) {
-            if(pattern.sequence.size > segment.size || (pattern.altSequence!=null && pattern.altSequence.size > segment.size))
-                continue        //  don't accept patterns that don't fit
-            val opcodesList = opcodes.subList(0, pattern.sequence.size)
-            if(pattern.sequence == opcodesList) {
-                val asm = pattern.asm(segment)
-                if(asm!=null)
-                    result.add(AsmFragment(asm, pattern.sequence.size))
-            } else if(pattern.altSequence!=null) {
-                val opcodesListAlt = opcodes.subList(0, pattern.altSequence.size)
-                if(pattern.altSequence == opcodesListAlt) {
-                    val asm = pattern.asm(segment)
-                    if (asm != null)
-                        result.add(AsmFragment(asm, pattern.sequence.size))
-                }
-            }
-        }
-
-        return result
-    }
-
-    private fun sameConstantIndexedVarOperation(variable: String, index: Int, ins: Instruction): AsmFragment? {
-        // an in place operation that consists of a push-value / op / push-index-value / pop-into-indexed-var
-        return when(ins.opcode) {
-            Opcode.SHL_BYTE -> AsmFragment(" asl  $variable+$index", 8)
-            Opcode.SHR_UBYTE -> AsmFragment(" lsr  $variable+$index", 8)
-            Opcode.SHR_SBYTE -> AsmFragment(" lda  $variable+$index |  asl  a |  ror  $variable+$index")
-            Opcode.SHL_WORD -> AsmFragment(" asl  $variable+${index * 2 + 1} |  rol  $variable+${index * 2}", 8)
-            Opcode.SHR_UWORD -> AsmFragment(" lsr  $variable+${index * 2 + 1} |  ror  $variable+${index * 2}", 8)
-            Opcode.SHR_SWORD -> AsmFragment(" lda  $variable+${index * 2 + 1} |  asl  a |  ror  $variable+${index * 2 + 1} |  ror  $variable+${index * 2}", 8)
-            Opcode.ROL_BYTE -> AsmFragment(" rol  $variable+$index", 8)
-            Opcode.ROR_BYTE -> AsmFragment(" ror  $variable+$index", 8)
-            Opcode.ROL_WORD -> AsmFragment(" rol  $variable+${index * 2 + 1} |  rol  $variable+${index * 2}", 8)
-            Opcode.ROR_WORD -> AsmFragment(" ror  $variable+${index * 2 + 1} |  ror  $variable+${index * 2}", 8)
-            Opcode.ROL2_BYTE -> AsmFragment(" lda  $variable+$index |  cmp  #\$80 |  rol  $variable+$index", 8)
-            Opcode.ROR2_BYTE -> AsmFragment(" lda  $variable+$index |  lsr  a |  bcc  + |  ora  #\$80 |+ |  sta  $variable+$index", 10)
-            Opcode.ROL2_WORD -> AsmFragment(" asl  $variable+${index * 2 + 1} |  rol  $variable+${index * 2} |  bcc  + |  inc  $variable+${index * 2 + 1} |+", 20)
-            Opcode.ROR2_WORD -> AsmFragment(" lsr  $variable+${index * 2 + 1} |  ror  $variable+${index * 2} |  bcc  + |  lda  $variable+${index * 2 + 1} |  ora  #\$80 |  sta  $variable+${index * 2 + 1} |+", 30)
-            Opcode.INC_INDEXED_VAR_B, Opcode.INC_INDEXED_VAR_UB -> AsmFragment(" inc  $variable+$index", 2)
-            Opcode.DEC_INDEXED_VAR_B, Opcode.DEC_INDEXED_VAR_UB -> AsmFragment(" dec  $variable+$index", 5)
-            Opcode.INC_INDEXED_VAR_W, Opcode.INC_INDEXED_VAR_UW -> AsmFragment(" inc  $variable+${index * 2} |  bne  + |  inc  $variable+${index * 2 + 1} |+")
-            Opcode.DEC_INDEXED_VAR_W, Opcode.DEC_INDEXED_VAR_UW -> AsmFragment(" lda  $variable+${index * 2} |  bne  + |  dec  $variable+${index * 2 + 1} |+ |  dec  $variable+${index * 2}")
-            Opcode.INC_INDEXED_VAR_FLOAT -> AsmFragment(
-                    """
-                lda  #<($variable+${index * MachineDefinition.Mflpt5.MemorySize})
-                ldy  #>($variable+${index * MachineDefinition.Mflpt5.MemorySize})
-                jsr  c64flt.inc_var_f
-                """)
-            Opcode.DEC_INDEXED_VAR_FLOAT -> AsmFragment(
-                    """
-                lda  #<($variable+${index * MachineDefinition.Mflpt5.MemorySize})
-                ldy  #>($variable+${index * MachineDefinition.Mflpt5.MemorySize})
-                jsr  c64flt.dec_var_f
-                """)
-
-            else -> null
-        }
-    }
-
-    private fun sameIndexedVarOperation(variable: String, indexVar: String, ins: Instruction): AsmFragment? {
-        // an in place operation that consists of a push-value / op / push-index-var / pop-into-indexed-var
-        val saveX = " stx  ${MachineDefinition.C64Zeropage.SCRATCH_B1} |"
-        val restoreX = " | ldx  ${MachineDefinition.C64Zeropage.SCRATCH_B1}"
-        val loadXWord: String
-        val loadX: String
-
-        when(indexVar) {
-            "X" -> {
-                loadX = ""
-                loadXWord = " txa |  asl  a |  tax |"
-            }
-            "Y" -> {
-                loadX = " tya |  tax |"
-                loadXWord = " tya |  asl  a |  tax |"
-            }
-            "A" -> {
-                loadX = " tax |"
-                loadXWord = " asl  a |  tax |"
-            }
-            else -> {
-                // the indexvar is a real variable, not a register
-                loadX = " ldx  $indexVar |"
-                loadXWord = " lda  $indexVar |  asl  a |  tax |"
-            }
-        }
-
-        return when (ins.opcode) {
-            Opcode.SHL_BYTE -> AsmFragment(" txa |  $loadX  asl  $variable,x |  tax", 10)
-            Opcode.SHR_UBYTE -> AsmFragment(" txa |  $loadX  lsr  $variable,x |  tax", 10)
-            Opcode.SHR_SBYTE -> AsmFragment("$saveX  $loadX  lda  $variable,x |  asl a |  ror  $variable,x  $restoreX", 10)
-            Opcode.SHL_WORD -> AsmFragment("$saveX $loadXWord  asl  $variable,x |  rol  $variable+1,x  $restoreX", 10)
-            Opcode.SHR_UWORD -> AsmFragment("$saveX $loadXWord  lsr  $variable+1,x |  ror  $variable,x  $restoreX", 10)
-            Opcode.SHR_SWORD -> AsmFragment("$saveX $loadXWord  lda  $variable+1,x |  asl a |  ror  $variable+1,x |  ror  $variable,x  $restoreX", 10)
-            Opcode.ROL_BYTE -> AsmFragment(" txa |  $loadX  rol  $variable,x |  tax", 10)
-            Opcode.ROR_BYTE -> AsmFragment(" txa |  $loadX  ror  $variable,x |  tax", 10)
-            Opcode.ROL_WORD -> AsmFragment("$saveX $loadXWord  rol  $variable,x |  rol  $variable+1,x  $restoreX", 10)
-            Opcode.ROR_WORD -> AsmFragment("$saveX $loadXWord  ror  $variable+1,x |  ror  $variable,x  $restoreX", 10)
-            Opcode.ROL2_BYTE -> AsmFragment("$saveX $loadX  lda  $variable,x |  cmp  #\$80 |  rol  $variable,x  $restoreX", 10)
-            Opcode.ROR2_BYTE -> AsmFragment("$saveX $loadX  lda  $variable,x |  lsr  a |  bcc  + |  ora  #\$80 |+ |  sta  $variable,x  $restoreX", 10)
-            Opcode.ROL2_WORD -> AsmFragment(" txa |  $loadXWord  asl  $variable,x |  rol  $variable+1,x |  bcc  + |  inc  $variable,x  |+  |  tax", 30)
-            Opcode.ROR2_WORD -> AsmFragment("$saveX $loadXWord  lsr  $variable+1,x |  ror  $variable,x |  bcc  + |  lda  $variable+1,x |  ora  #\$80 |  sta  $variable+1,x |+  $restoreX", 30)
-            Opcode.INC_INDEXED_VAR_B, Opcode.INC_INDEXED_VAR_UB -> AsmFragment(" txa |  $loadX  inc  $variable,x |  tax", 10)
-            Opcode.DEC_INDEXED_VAR_B, Opcode.DEC_INDEXED_VAR_UB -> AsmFragment(" txa |  $loadX  dec  $variable,x |  tax", 10)
-            Opcode.INC_INDEXED_VAR_W, Opcode.INC_INDEXED_VAR_UW -> AsmFragment("$saveX $loadXWord  inc  $variable,x |  bne  + |  inc  $variable+1,x  |+  $restoreX", 10)
-            Opcode.DEC_INDEXED_VAR_W, Opcode.DEC_INDEXED_VAR_UW -> AsmFragment("$saveX $loadXWord  lda  $variable,x |  bne  + |  dec  $variable+1,x |+ |  dec  $variable,x  $restoreX", 10)
-            Opcode.INC_INDEXED_VAR_FLOAT -> AsmFragment(" lda  #<$variable |  ldy  #>$variable |  $saveX   $loadX   jsr  c64flt.inc_indexed_var_f  $restoreX")
-            Opcode.DEC_INDEXED_VAR_FLOAT -> AsmFragment(" lda  #<$variable |  ldy  #>$variable |  $saveX   $loadX   jsr  c64flt.dec_indexed_var_f  $restoreX")
-
-            else -> null
-        }
-    }
-
-    private fun sameMemOperation(address: Int, ins: Instruction): AsmFragment? {
-        // an in place operation that consists of  push-mem / op / pop-mem
-        val addr = address.toHex()
-        val addrHi = (address+1).toHex()
-        return when(ins.opcode) {
-            Opcode.SHL_BYTE -> AsmFragment(" asl  $addr", 10)
-            Opcode.SHR_UBYTE -> AsmFragment(" lsr  $addr", 10)
-            Opcode.SHR_SBYTE -> AsmFragment(" lda  $addr |  asl  a |  ror  $addr", 10)
-            Opcode.SHL_WORD -> AsmFragment(" asl  $addr |  rol  $addrHi", 10)
-            Opcode.SHR_UWORD -> AsmFragment(" lsr  $addrHi |  ror  $addr", 10)
-            Opcode.SHR_SWORD -> AsmFragment(" lda  $addrHi |  asl a |  ror  $addrHi |  ror  $addr", 10)
-            Opcode.ROL_BYTE -> AsmFragment(" rol  $addr", 10)
-            Opcode.ROR_BYTE -> AsmFragment(" ror  $addr", 10)
-            Opcode.ROL_WORD -> AsmFragment(" rol  $addr |  rol  $addrHi", 10)
-            Opcode.ROR_WORD -> AsmFragment(" ror  $addrHi |  ror  $addr", 10)
-            Opcode.ROL2_BYTE -> AsmFragment(" lda  $addr |  cmp  #\$80 |  rol  $addr", 10)
-            Opcode.ROR2_BYTE -> AsmFragment(" lda  $addr |  lsr  a |  bcc  + |  ora  #\$80 |+ |  sta  $addr", 10)
-            Opcode.ROL2_WORD -> AsmFragment(" lda  $addr |  cmp #\$80 |  rol  $addr |  rol  $addrHi", 10)
-            Opcode.ROR2_WORD -> AsmFragment(" lsr  $addrHi |  ror  $addr |  bcc  + |  lda  $addrHi |  ora  #$80 |  sta  $addrHi |+", 20)
-            else -> null
-        }
-    }
-
-    private fun sameVarOperation(variable: String, ins: Instruction): AsmFragment? {
-        // an in place operation that consists of a push-var / op / pop-var
-        return when(ins.opcode) {
-            Opcode.SHL_BYTE -> {
-                when (variable) {
-                    "A" -> AsmFragment(" asl  a", 10)
-                    "X" -> AsmFragment(" txa |  asl  a |  tax", 10)
-                    "Y" -> AsmFragment(" tya |  asl  a |  tay", 10)
-                    else -> AsmFragment(" asl  $variable", 10)
-                }
-            }
-            Opcode.SHR_UBYTE -> {
-                when (variable) {
-                    "A" -> AsmFragment(" lsr  a", 10)
-                    "X" -> AsmFragment(" txa |  lsr  a |  tax", 10)
-                    "Y" -> AsmFragment(" tya |  lsr  a |  tay", 10)
-                    else -> AsmFragment(" lsr  $variable", 10)
-                }
-            }
-            Opcode.SHR_SBYTE -> {
-                // arithmetic shift right (keep sign bit)
-                when (variable) {
-                    "A" -> AsmFragment(" cmp  #$80 |  ror  a", 10)
-                    "X" -> AsmFragment(" txa |  cmp  #$80 |  ror  a |  tax", 10)
-                    "Y" -> AsmFragment(" tya |  cmp  #$80 |  ror  a |  tay", 10)
-                    else -> AsmFragment(" lda  $variable |  asl  a  | ror  $variable", 10)
-                }
-            }
-            Opcode.SHL_WORD -> {
-                AsmFragment(" asl  $variable |  rol  $variable+1", 10)
-            }
-            Opcode.SHR_UWORD -> {
-                AsmFragment(" lsr  $variable+1 |  ror  $variable", 10)
-            }
-            Opcode.SHR_SWORD -> {
-                // arithmetic shift right (keep sign bit)
-                AsmFragment(" lda  $variable+1 |  asl  a |  ror  $variable+1 |  ror  $variable", 10)
-            }
-            Opcode.ROL_BYTE -> {
-                when (variable) {
-                    "A" -> AsmFragment(" rol  a", 10)
-                    "X" -> AsmFragment(" txa |  rol  a |  tax", 10)
-                    "Y" -> AsmFragment(" tya |  rol  a |  tay", 10)
-                    else -> AsmFragment(" rol  $variable", 10)
-                }
-            }
-            Opcode.ROR_BYTE -> {
-                when (variable) {
-                    "A" -> AsmFragment(" ror  a", 10)
-                    "X" -> AsmFragment(" txa |  ror  a |  tax", 10)
-                    "Y" -> AsmFragment(" tya |  ror  a |  tay", 10)
-                    else -> AsmFragment(" ror  $variable", 10)
-                }
-            }
-            Opcode.ROL_WORD -> {
-                AsmFragment(" rol  $variable |  rol  $variable+1", 10)
-            }
-            Opcode.ROR_WORD -> {
-                AsmFragment(" ror  $variable+1 |  ror  $variable", 10)
-            }
-            Opcode.ROL2_BYTE -> {       // 8-bit rol
-                when (variable) {
-                    "A" -> AsmFragment(" cmp  #\$80 |  rol  a", 10)
-                    "X" -> AsmFragment(" txa |  cmp  #\$80 |  rol  a |  tax", 10)
-                    "Y" -> AsmFragment(" tya |  cmp  #\$80 |  rol  a |  tay", 10)
-                    else -> AsmFragment(" lda  $variable |  cmp  #\$80  | rol  $variable", 10)
-                }
-            }
-            Opcode.ROR2_BYTE -> {       // 8-bit ror
-                when (variable) {
-                    "A" -> AsmFragment(" lsr  a | bcc  + |  ora  #\$80  |+", 10)
-                    "X" -> AsmFragment(" txa |  lsr  a |  bcc  + |  ora  #\$80  |+ |  tax", 10)
-                    "Y" -> AsmFragment(" tya |  lsr  a |  bcc  + |  ora  #\$80  |+ |  tay", 10)
-                    else -> AsmFragment(" lda  $variable |  lsr  a |  bcc  + |  ora  #\$80 |+ |  sta  $variable", 10)
-                }
-            }
-            Opcode.ROL2_WORD -> {
-                AsmFragment(" lda  $variable |  cmp #\$80 |  rol  $variable |  rol  $variable+1", 10)
-            }
-            Opcode.ROR2_WORD -> {
-                AsmFragment(" lsr  $variable+1 |  ror  $variable |  bcc  + |  lda  $variable+1 |  ora  #\$80 |  sta  $variable+1 |+", 30)
-            }
-            else -> null
-        }
-    }
-
-    private class AsmFragment(val asm: String, var segmentSize: Int=0)
-}

DeprecatedStackVm/src/compiler/target/c64/codegen/SimpleAsm.kt

@@ -1,559 +0,0 @@
-package compiler.target.c64.codegen
-
-import prog8.compiler.CompilerException
-import prog8.compiler.intermediate.Instruction
-import prog8.compiler.intermediate.IntermediateProgram
-import prog8.compiler.intermediate.LabelInstr
-import prog8.compiler.intermediate.Opcode
-import prog8.compiler.target.c64.MachineDefinition.C64Zeropage
-import prog8.compiler.target.c64.MachineDefinition.ESTACK_HI_HEX
-import prog8.compiler.target.c64.MachineDefinition.ESTACK_HI_PLUS1_HEX
-import prog8.compiler.target.c64.MachineDefinition.ESTACK_LO_HEX
-import prog8.compiler.target.c64.MachineDefinition.ESTACK_LO_PLUS1_HEX
-import prog8.compiler.target.c64.MachineDefinition.ESTACK_LO_PLUS2_HEX
-import prog8.compiler.toHex
-import prog8.vm.stackvm.Syscall
-import prog8.vm.stackvm.syscallsForStackVm
-
-
-// note: see https://wiki.nesdev.com/w/index.php/6502_assembly_optimisations
-
-
-private var breakpointCounter = 0
-
-internal fun simpleInstr2Asm(ins: Instruction, block: IntermediateProgram.ProgramBlock): String? {
-    // a label 'instruction' is simply translated into a asm label
-    if(ins is LabelInstr) {
-        val labelresult =
-                if(ins.name.startsWith("${block.name}."))
-                    ins.name.substring(block.name.length+1)
-                else
-                    ins.name
-        return if(ins.asmProc) labelresult+"\t\t.proc" else labelresult
-    }
-
-    // simple opcodes that are translated directly into one or a few asm instructions
-    return when(ins.opcode) {
-        Opcode.LINE -> " ;\tsrc line: ${ins.callLabel}"
-        Opcode.NOP -> " nop"      // shouldn't be present anymore though
-        Opcode.START_PROCDEF -> ""  // is done as part of a label
-        Opcode.END_PROCDEF -> " .pend"
-        Opcode.TERMINATE -> " brk"
-        Opcode.SEC -> " sec"
-        Opcode.CLC -> " clc"
-        Opcode.SEI -> " sei"
-        Opcode.CLI -> " cli"
-        Opcode.CARRY_TO_A -> " lda  #0 |  adc  #0"
-        Opcode.JUMP -> {
-            if(ins.callLabel!=null)
-                " jmp  ${ins.callLabel}"
-            else
-                " jmp  ${hexVal(ins)}"
-        }
-        Opcode.CALL -> {
-            if(ins.callLabel!=null)
-                " jsr  ${ins.callLabel}"
-            else
-                " jsr  ${hexVal(ins)}"
-        }
-        Opcode.RETURN -> " rts"
-        Opcode.RSAVE -> {
-            // save cpu status flag and all registers A, X, Y.
-            // see http://6502.org/tutorials/register_preservation.html
-            " php |  sta  ${C64Zeropage.SCRATCH_REG} | pha  | txa  | pha  | tya  | pha  | lda  ${C64Zeropage.SCRATCH_REG}"
-        }
-        Opcode.RRESTORE -> {
-            // restore all registers and cpu status flag
-            " pla |  tay |  pla |  tax |  pla |  plp"
-        }
-        Opcode.RSAVEX -> " sta  ${C64Zeropage.SCRATCH_REG} |  txa |  pha |  lda  ${C64Zeropage.SCRATCH_REG}"
-        Opcode.RRESTOREX -> " sta  ${C64Zeropage.SCRATCH_REG} |  pla |  tax |  lda  ${C64Zeropage.SCRATCH_REG}"
-        Opcode.DISCARD_BYTE -> " inx"
-        Opcode.DISCARD_WORD -> " inx"
-        Opcode.DISCARD_FLOAT -> " inx |  inx |  inx"
-        Opcode.DUP_B -> {
-            " lda $ESTACK_LO_PLUS1_HEX,x | sta $ESTACK_LO_HEX,x | dex | ;DUP_B "
-        }
-        Opcode.DUP_W -> {
-            " lda $ESTACK_LO_PLUS1_HEX,x | sta $ESTACK_LO_HEX,x | lda $ESTACK_HI_PLUS1_HEX,x | sta $ESTACK_HI_HEX,x | dex "
-        }
-
-        Opcode.CMP_B, Opcode.CMP_UB -> {
-            " inx | lda $ESTACK_LO_HEX,x | cmp #${ins.arg!!.integerValue().toHex()} | ;CMP_B "
-        }
-
-        Opcode.CMP_W, Opcode.CMP_UW -> {
-            """
-            inx
-            lda   $ESTACK_HI_HEX,x
-            cmp   #>${ins.arg!!.integerValue().toHex()}
-            bne   +
-            lda   $ESTACK_LO_HEX,x
-            cmp   #<${ins.arg.integerValue().toHex()}
-            ; bne   +    not necessary?
-            ; lda   #0   not necessary?
-+                           
-            """
-        }
-
-        Opcode.INLINE_ASSEMBLY ->  "@inline@" + (ins.callLabel2 ?: "")      // All of the inline assembly is stored in the calllabel2 property. the '@inline@' is a special marker to accept it.
-        Opcode.INCLUDE_FILE -> {
-            val offset = if(ins.arg==null) "" else ", ${ins.arg.integerValue()}"
-            val length = if(ins.arg2==null) "" else ", ${ins.arg2.integerValue()}"
-            " .binary  \"${ins.callLabel}\" $offset $length"
-        }
-        Opcode.SYSCALL -> {
-            if (ins.arg!!.numericValue() in syscallsForStackVm.map { it.callNr })
-                throw CompilerException("cannot translate vm syscalls to real assembly calls - use *real* subroutine calls instead. Syscall ${ins.arg.numericValue()}")
-            val call = Syscall.values().find { it.callNr==ins.arg.numericValue() }
-            when(call) {
-                Syscall.FUNC_SIN,
-                Syscall.FUNC_COS,
-                Syscall.FUNC_ABS,
-                Syscall.FUNC_TAN,
-                Syscall.FUNC_ATAN,
-                Syscall.FUNC_LN,
-                Syscall.FUNC_LOG2,
-                Syscall.FUNC_SQRT,
-                Syscall.FUNC_RAD,
-                Syscall.FUNC_DEG,
-                Syscall.FUNC_ROUND,
-                Syscall.FUNC_FLOOR,
-                Syscall.FUNC_CEIL,
-                Syscall.FUNC_RNDF,
-                Syscall.FUNC_ANY_F,
-                Syscall.FUNC_ALL_F,
-                Syscall.FUNC_MAX_F,
-                Syscall.FUNC_MIN_F,
-                Syscall.FUNC_SUM_F -> " jsr  c64flt.${call.name.toLowerCase()}"
-                null -> ""
-                else -> " jsr  prog8_lib.${call.name.toLowerCase()}"
-            }
-        }
-        Opcode.BREAKPOINT -> {
-            breakpointCounter++
-            "_prog8_breakpoint_$breakpointCounter\tnop"
-        }
-
-        Opcode.PUSH_BYTE -> {
-            " lda  #${hexVal(ins)} |  sta  $ESTACK_LO_HEX,x |  dex"
-        }
-        Opcode.PUSH_WORD -> {
-            val value = hexVal(ins)
-            " lda  #<$value |  sta  $ESTACK_LO_HEX,x |  lda  #>$value |  sta  $ESTACK_HI_HEX,x |  dex"
-        }
-        Opcode.PUSH_FLOAT -> {
-            val floatConst = getFloatConst(ins.arg!!)
-            " lda  #<$floatConst |  ldy  #>$floatConst |  jsr  c64flt.push_float"
-        }
-        Opcode.PUSH_VAR_BYTE -> {
-            when(ins.callLabel) {
-                "X" -> throw CompilerException("makes no sense to push X, it's used as a stack pointer itself. You should probably not use the X register (or only in trivial assignments)")
-                "A" -> " sta  $ESTACK_LO_HEX,x |  dex"
-                "Y" -> " tya |  sta  $ESTACK_LO_HEX,x |  dex"
-                else -> " lda  ${ins.callLabel} |  sta  $ESTACK_LO_HEX,x |  dex"
-            }
-        }
-        Opcode.PUSH_VAR_WORD -> {
-            " lda  ${ins.callLabel} |  sta  $ESTACK_LO_HEX,x |  lda  ${ins.callLabel}+1 |    sta  $ESTACK_HI_HEX,x |  dex"
-        }
-        Opcode.PUSH_VAR_FLOAT -> " lda  #<${ins.callLabel} |  ldy  #>${ins.callLabel}|  jsr  c64flt.push_float"
-        Opcode.PUSH_MEM_B, Opcode.PUSH_MEM_UB -> {
-            """
-                lda  ${hexVal(ins)}
-                sta  $ESTACK_LO_HEX,x
-                dex
-                """
-        }
-        Opcode.PUSH_MEM_W, Opcode.PUSH_MEM_UW -> {
-            """
-                lda  ${hexVal(ins)}
-                sta  $ESTACK_LO_HEX,x
-                lda  ${hexValPlusOne(ins)}
-                sta  $ESTACK_HI_HEX,x
-                dex
-                """
-        }
-        Opcode.PUSH_MEM_FLOAT -> {
-            " lda  #<${hexVal(ins)} |  ldy  #>${hexVal(ins)}|  jsr  c64flt.push_float"
-        }
-        Opcode.PUSH_MEMREAD -> {
-            """
-                lda  $ESTACK_LO_PLUS1_HEX,x
-                sta  (+) +1
-                lda  $ESTACK_HI_PLUS1_HEX,x
-                sta  (+) +2
-+               lda  65535    ; modified
-                sta  $ESTACK_LO_PLUS1_HEX,x
-                """
-        }
-
-        Opcode.PUSH_REGAY_WORD -> {
-            " sta  $ESTACK_LO_HEX,x |  tya |  sta  $ESTACK_HI_HEX,x |  dex "
-        }
-        Opcode.PUSH_ADDR_HEAPVAR -> {
-            " lda  #<${ins.callLabel} |  sta  $ESTACK_LO_HEX,x |  lda  #>${ins.callLabel}  |  sta  $ESTACK_HI_HEX,x |  dex"
-        }
-        Opcode.POP_REGAX_WORD -> throw AssemblyError("cannot load X register from stack because it's used as the stack pointer itself")
-        Opcode.POP_REGXY_WORD -> throw AssemblyError("cannot load X register from stack because it's used as the stack pointer itself")
-        Opcode.POP_REGAY_WORD -> {
-            " inx |  lda  $ESTACK_LO_HEX,x |  ldy  $ESTACK_HI_HEX,x "
-        }
-
-        Opcode.READ_INDEXED_VAR_BYTE -> {
-            """
-                ldy  $ESTACK_LO_PLUS1_HEX,x
-                lda  ${ins.callLabel},y
-                sta  $ESTACK_LO_PLUS1_HEX,x
-                """
-        }
-        Opcode.READ_INDEXED_VAR_WORD -> {
-            """
-                lda  $ESTACK_LO_PLUS1_HEX,x
-                asl  a
-                tay
-                lda  ${ins.callLabel},y
-                sta  $ESTACK_LO_PLUS1_HEX,x
-                lda  ${ins.callLabel}+1,y
-                sta  $ESTACK_HI_PLUS1_HEX,x
-                """
-        }
-        Opcode.READ_INDEXED_VAR_FLOAT -> {
-            """
-                lda  #<${ins.callLabel}
-                ldy  #>${ins.callLabel}
-                jsr  c64flt.push_float_from_indexed_var
-                """
-        }
-        Opcode.WRITE_INDEXED_VAR_BYTE -> {
-            """
-                inx
-                ldy  $ESTACK_LO_HEX,x
-                inx
-                lda  $ESTACK_LO_HEX,x
-                sta  ${ins.callLabel},y
-                """
-        }
-        Opcode.WRITE_INDEXED_VAR_WORD -> {
-            """
-                inx
-                lda  $ESTACK_LO_HEX,x
-                asl  a
-                tay
-                inx
-                lda  $ESTACK_LO_HEX,x
-                sta  ${ins.callLabel},y
-                lda  $ESTACK_HI_HEX,x
-                sta  ${ins.callLabel}+1,y
-                """
-        }
-        Opcode.WRITE_INDEXED_VAR_FLOAT -> {
-            """
-                lda  #<${ins.callLabel}
-                ldy  #>${ins.callLabel}
-                jsr  c64flt.pop_float_to_indexed_var
-                """
-        }
-        Opcode.POP_MEM_BYTE -> {
-            """
-                inx
-                lda  $ESTACK_LO_HEX,x
-                sta  ${hexVal(ins)}
-                """
-        }
-        Opcode.POP_MEM_WORD -> {
-            """
-                inx
-                lda  $ESTACK_LO_HEX,x
-                sta  ${hexVal(ins)}
-                lda  $ESTACK_HI_HEX,x
-                sta  ${hexValPlusOne(ins)}
-                """
-        }
-        Opcode.POP_MEM_FLOAT -> {
-            " lda  ${hexVal(ins)} |  ldy  ${hexValPlusOne(ins)} |  jsr  c64flt.pop_float"
-        }
-        Opcode.POP_MEMWRITE -> {
-            """
-                inx
-                lda  $ESTACK_LO_HEX,x
-                sta  (+) +1
-                lda  $ESTACK_HI_HEX,x
-                sta  (+) +2
-                inx
-                lda  $ESTACK_LO_HEX,x
-+               sta  65535       ; modified
-                """
-        }
-
-        Opcode.POP_VAR_BYTE -> {
-            when (ins.callLabel) {
-                "X" -> throw CompilerException("makes no sense to pop X, it's used as a stack pointer itself")
-                "A" -> " inx |  lda  $ESTACK_LO_HEX,x"
-                "Y" -> " inx |  ldy  $ESTACK_LO_HEX,x"
-                else -> " inx |  lda  $ESTACK_LO_HEX,x |  sta  ${ins.callLabel}"
-            }
-        }
-        Opcode.POP_VAR_WORD -> {
-            " inx |  lda  $ESTACK_LO_HEX,x |  ldy  $ESTACK_HI_HEX,x |  sta  ${ins.callLabel} |  sty  ${ins.callLabel}+1"
-        }
-        Opcode.POP_VAR_FLOAT -> {
-            " lda  #<${ins.callLabel} |  ldy  #>${ins.callLabel} |  jsr  c64flt.pop_float"
-        }
-
-        Opcode.INC_VAR_UB, Opcode.INC_VAR_B -> {
-            when (ins.callLabel) {
-                "A" -> " clc |  adc  #1"
-                "X" -> " inx"
-                "Y" -> " iny"
-                else -> " inc  ${ins.callLabel}"
-            }
-        }
-        Opcode.INC_VAR_UW, Opcode.INC_VAR_W -> {
-            " inc  ${ins.callLabel} |  bne  + |  inc  ${ins.callLabel}+1 |+"
-        }
-        Opcode.INC_VAR_F -> {
-            """
-                lda  #<${ins.callLabel}
-                ldy  #>${ins.callLabel}
-                jsr  c64flt.inc_var_f
-                """
-        }
-        Opcode.POP_INC_MEMORY -> {
-            """
-                inx
-                lda  $ESTACK_LO_HEX,x
-                sta  (+) +1
-                lda  $ESTACK_HI_HEX,x
-                sta  (+) +2
-+               inc  65535     ; modified
-                """
-        }
-        Opcode.POP_DEC_MEMORY -> {
-            """
-                inx
-                lda  $ESTACK_LO_HEX,x
-                sta  (+) +1
-                lda  $ESTACK_HI_HEX,x
-                sta  (+) +2
-+               dec  65535     ; modified
-                """
-        }
-        Opcode.DEC_VAR_UB, Opcode.DEC_VAR_B -> {
-            when (ins.callLabel) {
-                "A" -> " sec |  sbc  #1"
-                "X" -> " dex"
-                "Y" -> " dey"
-                else -> " dec  ${ins.callLabel}"
-            }
-        }
-        Opcode.DEC_VAR_UW, Opcode.DEC_VAR_W -> {
-            " lda  ${ins.callLabel} |  bne  + |  dec  ${ins.callLabel}+1 |+ |  dec  ${ins.callLabel}"
-        }
-        Opcode.DEC_VAR_F -> {
-            """
-                lda  #<${ins.callLabel}
-                ldy  #>${ins.callLabel}
-                jsr  c64flt.dec_var_f
-                """
-        }
-        Opcode.INC_MEMORY -> " inc  ${hexVal(ins)}"
-        Opcode.DEC_MEMORY -> " dec  ${hexVal(ins)}"
-        Opcode.INC_INDEXED_VAR_B, Opcode.INC_INDEXED_VAR_UB -> " inx |  txa |  pha |  lda  $ESTACK_LO_HEX,x |  tax |  inc  ${ins.callLabel},x |  pla |  tax"
-        Opcode.DEC_INDEXED_VAR_B, Opcode.DEC_INDEXED_VAR_UB -> " inx |  txa |  pha |  lda  $ESTACK_LO_HEX,x |  tax |  dec  ${ins.callLabel},x |  pla |  tax"
-
-        Opcode.NEG_B -> " jsr  prog8_lib.neg_b"
-        Opcode.NEG_W -> " jsr  prog8_lib.neg_w"
-        Opcode.NEG_F -> " jsr  c64flt.neg_f"
-        Opcode.ABS_B -> " jsr  prog8_lib.abs_b"
-        Opcode.ABS_W -> " jsr  prog8_lib.abs_w"
-        Opcode.ABS_F -> " jsr  c64flt.abs_f"
-        Opcode.POW_F -> " jsr  c64flt.pow_f"
-        Opcode.INV_BYTE -> {
-            """
-                lda  $ESTACK_LO_PLUS1_HEX,x
-                eor  #255
-                sta  $ESTACK_LO_PLUS1_HEX,x
-                """
-        }
-        Opcode.INV_WORD -> " jsr  prog8_lib.inv_word"
-        Opcode.NOT_BYTE -> " jsr  prog8_lib.not_byte"
-        Opcode.NOT_WORD -> " jsr  prog8_lib.not_word"
-        Opcode.BCS -> {
-            val label = ins.callLabel ?: hexVal(ins)
-            " bcs  $label"
-        }
-        Opcode.BCC -> {
-            val label = ins.callLabel ?: hexVal(ins)
-            " bcc  $label"
-        }
-        Opcode.BNEG -> {
-            val label = ins.callLabel ?: hexVal(ins)
-            " bmi  $label"
-        }
-        Opcode.BPOS -> {
-            val label = ins.callLabel ?: hexVal(ins)
-            " bpl  $label"
-        }
-        Opcode.BVC -> {
-            val label = ins.callLabel ?: hexVal(ins)
-            " bvc  $label"
-        }
-        Opcode.BVS -> {
-            val label = ins.callLabel ?: hexVal(ins)
-            " bvs  $label"
-        }
-        Opcode.BZ -> {
-            val label = ins.callLabel ?: hexVal(ins)
-            " beq  $label"
-        }
-        Opcode.BNZ -> {
-            val label = ins.callLabel ?: hexVal(ins)
-            " bne  $label"
-        }
-        Opcode.JZ -> {
-            val label = ins.callLabel ?: hexVal(ins)
-            """
-                inx
-                lda  $ESTACK_LO_HEX,x
-                beq  $label
-                """
-        }
-        Opcode.JZW -> {
-            val label = ins.callLabel ?: hexVal(ins)
-            """
-                inx
-                lda  $ESTACK_LO_HEX,x
-                beq  $label
-                lda  $ESTACK_HI_HEX,x
-                beq  $label
-                """
-        }
-        Opcode.JNZ -> {
-            val label = ins.callLabel ?: hexVal(ins)
-            """
-                inx
-                lda  $ESTACK_LO_HEX,x
-                bne  $label
-                """
-        }
-        Opcode.JNZW -> {
-            val label = ins.callLabel ?: hexVal(ins)
-            """
-                inx
-                lda  $ESTACK_LO_HEX,x
-                bne  $label
-                lda  $ESTACK_HI_HEX,x
-                bne  $label
-                """
-        }
-        Opcode.CAST_B_TO_UB -> ""  // is a no-op, just carry on with the byte as-is
-        Opcode.CAST_UB_TO_B -> ""  // is a no-op, just carry on with the byte as-is
-        Opcode.CAST_W_TO_UW -> ""  // is a no-op, just carry on with the word as-is
-        Opcode.CAST_UW_TO_W -> ""  // is a no-op, just carry on with the word as-is
-        Opcode.CAST_W_TO_UB -> ""  // is a no-op, just carry on with the lsb of the word as-is
-        Opcode.CAST_W_TO_B -> ""  // is a no-op, just carry on with the lsb of the word as-is
-        Opcode.CAST_UW_TO_UB -> ""  // is a no-op, just carry on with the lsb of the uword as-is
-        Opcode.CAST_UW_TO_B -> ""  // is a no-op, just carry on with the lsb of the uword as-is
-        Opcode.CAST_UB_TO_F -> " jsr  c64flt.stack_ub2float"
-        Opcode.CAST_B_TO_F -> " jsr  c64flt.stack_b2float"
-        Opcode.CAST_UW_TO_F -> " jsr  c64flt.stack_uw2float"
-        Opcode.CAST_W_TO_F -> " jsr  c64flt.stack_w2float"
-        Opcode.CAST_F_TO_UB -> " jsr  c64flt.stack_float2ub"
-        Opcode.CAST_F_TO_B -> " jsr  c64flt.stack_float2b"
-        Opcode.CAST_F_TO_UW -> " jsr  c64flt.stack_float2uw"
-        Opcode.CAST_F_TO_W -> " jsr  c64flt.stack_float2w"
-        Opcode.CAST_UB_TO_UW, Opcode.CAST_UB_TO_W -> " lda  #0 |  sta  $ESTACK_HI_PLUS1_HEX,x"     // clear the msb
-        Opcode.CAST_B_TO_UW, Opcode.CAST_B_TO_W -> " lda  $ESTACK_LO_PLUS1_HEX,x |  ${signExtendA("$ESTACK_HI_PLUS1_HEX,x")}"     // sign extend the lsb
-        Opcode.MSB -> " lda  $ESTACK_HI_PLUS1_HEX,x |  sta  $ESTACK_LO_PLUS1_HEX,x"
-        Opcode.MKWORD -> " inx |  lda  $ESTACK_LO_HEX,x |  sta  $ESTACK_HI_PLUS1_HEX,x "
-
-        Opcode.ADD_UB, Opcode.ADD_B -> {        // TODO inline better (pattern with more opcodes)
-            """
-                lda  $ESTACK_LO_PLUS2_HEX,x
-                clc
-                adc  $ESTACK_LO_PLUS1_HEX,x
-                inx
-                sta  $ESTACK_LO_PLUS1_HEX,x
-                """
-        }
-        Opcode.SUB_UB, Opcode.SUB_B -> {        // TODO inline better (pattern with more opcodes)
-            """
-                lda  $ESTACK_LO_PLUS2_HEX,x
-                sec
-                sbc  $ESTACK_LO_PLUS1_HEX,x
-                inx
-                sta  $ESTACK_LO_PLUS1_HEX,x
-                """
-        }
-        Opcode.ADD_W, Opcode.ADD_UW -> "  jsr  prog8_lib.add_w"
-        Opcode.SUB_W, Opcode.SUB_UW -> "  jsr  prog8_lib.sub_w"
-        Opcode.MUL_B, Opcode.MUL_UB -> "  jsr  prog8_lib.mul_byte"
-        Opcode.MUL_W, Opcode.MUL_UW -> "  jsr  prog8_lib.mul_word"
-        Opcode.MUL_F -> "  jsr  c64flt.mul_f"
-        Opcode.ADD_F -> "  jsr  c64flt.add_f"
-        Opcode.SUB_F -> "  jsr  c64flt.sub_f"
-        Opcode.DIV_F -> "  jsr  c64flt.div_f"
-        Opcode.IDIV_UB -> "  jsr  prog8_lib.idiv_ub"
-        Opcode.IDIV_B -> "  jsr  prog8_lib.idiv_b"
-        Opcode.IDIV_W -> "  jsr  prog8_lib.idiv_w"
-        Opcode.IDIV_UW -> "  jsr  prog8_lib.idiv_uw"
-
-        Opcode.AND_BYTE -> "  jsr  prog8_lib.and_b"
-        Opcode.OR_BYTE -> "  jsr  prog8_lib.or_b"
-        Opcode.XOR_BYTE -> "  jsr  prog8_lib.xor_b"
-        Opcode.AND_WORD -> "  jsr  prog8_lib.and_w"
-        Opcode.OR_WORD -> "  jsr  prog8_lib.or_w"
-        Opcode.XOR_WORD -> "  jsr  prog8_lib.xor_w"
-
-        Opcode.BITAND_BYTE -> "  jsr  prog8_lib.bitand_b"
-        Opcode.BITOR_BYTE -> "  jsr  prog8_lib.bitor_b"
-        Opcode.BITXOR_BYTE -> "  jsr  prog8_lib.bitxor_b"
-        Opcode.BITAND_WORD -> "  jsr  prog8_lib.bitand_w"
-        Opcode.BITOR_WORD -> "  jsr  prog8_lib.bitor_w"
-        Opcode.BITXOR_WORD -> "  jsr  prog8_lib.bitxor_w"
-
-        Opcode.REMAINDER_UB -> "  jsr  prog8_lib.remainder_ub"
-        Opcode.REMAINDER_UW -> "  jsr  prog8_lib.remainder_uw"
-
-        Opcode.GREATER_B -> "  jsr  prog8_lib.greater_b"
-        Opcode.GREATER_UB -> "  jsr  prog8_lib.greater_ub"
-        Opcode.GREATER_W -> "  jsr  prog8_lib.greater_w"
-        Opcode.GREATER_UW -> "  jsr  prog8_lib.greater_uw"
-        Opcode.GREATER_F -> "  jsr  c64flt.greater_f"
-
-        Opcode.GREATEREQ_B -> "  jsr  prog8_lib.greatereq_b"
-        Opcode.GREATEREQ_UB -> "  jsr  prog8_lib.greatereq_ub"
-        Opcode.GREATEREQ_W -> "  jsr  prog8_lib.greatereq_w"
-        Opcode.GREATEREQ_UW -> "  jsr  prog8_lib.greatereq_uw"
-        Opcode.GREATEREQ_F -> "  jsr  c64flt.greatereq_f"
-
-        Opcode.EQUAL_BYTE -> "  jsr  prog8_lib.equal_b"
-        Opcode.EQUAL_WORD -> "  jsr  prog8_lib.equal_w"
-        Opcode.EQUAL_F -> "  jsr  c64flt.equal_f"
-        Opcode.NOTEQUAL_BYTE -> "  jsr prog8_lib.notequal_b"
-        Opcode.NOTEQUAL_WORD -> "  jsr prog8_lib.notequal_w"
-        Opcode.NOTEQUAL_F -> "  jsr  c64flt.notequal_f"
-
-        Opcode.LESS_UB -> "  jsr  prog8_lib.less_ub"
-        Opcode.LESS_B -> "  jsr  prog8_lib.less_b"
-        Opcode.LESS_UW -> "  jsr  prog8_lib.less_uw"
-        Opcode.LESS_W -> "  jsr  prog8_lib.less_w"
-        Opcode.LESS_F -> "  jsr  c64flt.less_f"
-
-        Opcode.LESSEQ_UB -> "  jsr  prog8_lib.lesseq_ub"
-        Opcode.LESSEQ_B -> "  jsr  prog8_lib.lesseq_b"
-        Opcode.LESSEQ_UW -> "  jsr  prog8_lib.lesseq_uw"
-        Opcode.LESSEQ_W -> "  jsr  prog8_lib.lesseq_w"
-        Opcode.LESSEQ_F -> "  jsr  c64flt.lesseq_f"
-
-        Opcode.SHIFTEDL_BYTE -> "  asl  $ESTACK_LO_PLUS1_HEX,x"
-        Opcode.SHIFTEDL_WORD -> "  asl  $ESTACK_LO_PLUS1_HEX,x |  rol  $ESTACK_HI_PLUS1_HEX,x"
-        Opcode.SHIFTEDR_SBYTE -> "  lda  $ESTACK_LO_PLUS1_HEX,x |  asl  a |  ror  $ESTACK_LO_PLUS1_HEX,x"
-        Opcode.SHIFTEDR_UBYTE -> "  lsr  $ESTACK_LO_PLUS1_HEX,x"
-        Opcode.SHIFTEDR_SWORD -> "  lda  $ESTACK_HI_PLUS1_HEX,x |  asl a  |  ror  $ESTACK_HI_PLUS1_HEX,x |  ror  $ESTACK_LO_PLUS1_HEX,x"
-        Opcode.SHIFTEDR_UWORD -> "  lsr  $ESTACK_HI_PLUS1_HEX,x |  ror  $ESTACK_LO_PLUS1_HEX,x"
-
-        else -> null
-    }
-}

DeprecatedStackVm/src/prog8/vm/stackvm/Main.kt

@@ -1,47 +0,0 @@
-package prog8.vm.stackvm
-
-import prog8.printSoftwareHeader
-import prog8.vm.astvm.ScreenDialog
-import java.awt.EventQueue
-import javax.swing.Timer
-import kotlin.system.exitProcess
-
-fun main(args: Array<String>) {
-    stackVmMain(args)
-}
-
-fun stackVmMain(args: Array<String>) {
-    printSoftwareHeader("StackVM")
-
-    if(args.size != 1) {
-        System.err.println("requires one argument: name of stackvm sourcecode file")
-        exitProcess(1)
-    }
-
-    val program = Program.load(args.first())
-    val vm = StackVm(traceOutputFile = null)
-    val dialog = ScreenDialog("StackVM")
-    vm.load(program, dialog.canvas)
-    EventQueue.invokeLater {
-        dialog.pack()
-        dialog.isVisible = true
-        dialog.start()
-
-        val programTimer = Timer(10) { a ->
-            try {
-                vm.step()
-            } catch(bp: VmBreakpointException) {
-                println("Breakpoint: execution halted. Press enter to resume.")
-                readLine()
-            } catch (tx: VmTerminationException) {
-                println("Execution halted: ${tx.message}")
-                (a.source as Timer).stop()
-            }
-        }
-
-        val irqTimer = Timer(1000/60) { a -> vm.irq(a.`when`) }
-
-        programTimer.start()
-        irqTimer.start()
-    }
-}

DeprecatedStackVm/src/prog8/vm/stackvm/Program.kt

@@ -1,302 +0,0 @@
-package prog8.vm.stackvm
-
-import prog8.ast.antlr.unescape
-import prog8.ast.base.*
-import prog8.ast.expressions.AddressOf
-import prog8.ast.expressions.IdentifierReference
-import prog8.compiler.HeapValues
-import prog8.compiler.IntegerOrAddressOf
-import prog8.compiler.intermediate.Instruction
-import prog8.compiler.intermediate.LabelInstr
-import prog8.compiler.intermediate.Opcode
-import prog8.compiler.intermediate.opcodesWithVarArgument
-import prog8.vm.RuntimeValue
-import java.io.File
-import java.util.*
-import java.util.regex.Pattern
-
-class Program (val name: String,
-               val program: MutableList<Instruction>,
-               val variables: Map<String, RuntimeValue>,
-               val memoryPointers: Map<String, Pair<Int, DataType>>,
-               val labels: Map<String, Int>,
-               val memory: Map<Int, List<RuntimeValue>>,
-               val heap: HeapValues)
-{
-    init {
-        // add end of program marker and some sentinel instructions, to correctly connect all others
-        program.add(LabelInstr("____program_end", false))
-        program.add(Instruction(Opcode.TERMINATE))
-        program.add(Instruction(Opcode.NOP))
-    }
-
-    companion object {
-        fun load(filename: String): Program {
-            val lines = File(filename).readLines().withIndex().iterator()
-            val memory = mutableMapOf<Int, List<RuntimeValue>>()
-            val heap = HeapValues()
-            val program = mutableListOf<Instruction>()
-            val variables = mutableMapOf<String, RuntimeValue>()
-            val memoryPointers = mutableMapOf<String, Pair<Int, DataType>>()
-            val labels = mutableMapOf<String, Int>()
-
-            while(lines.hasNext()) {
-                val (lineNr, line) = lines.next()
-                if(line.startsWith(';') || line.isEmpty())
-                    continue
-                else if(line=="%memory")
-                    loadMemory(lines, memory)
-                else if(line=="%heap")
-                    loadHeap(lines, heap)
-                else if(line.startsWith("%block "))
-                    loadBlock(lines, heap, program, variables, memoryPointers, labels)
-                else throw VmExecutionException("syntax error at line ${lineNr + 1}")
-            }
-            return Program(filename, program, variables, memoryPointers, labels, memory, heap)
-        }
-
-        private fun loadBlock(lines: Iterator<IndexedValue<String>>,
-                              heap: HeapValues,
-                              program: MutableList<Instruction>,
-                              variables: MutableMap<String, RuntimeValue>,
-                              memoryPointers: MutableMap<String, Pair<Int, DataType>>,
-                              labels: MutableMap<String, Int>)
-        {
-            while(true) {
-                val (_, line) = lines.next()
-                if(line.isEmpty())
-                    continue
-                else if(line=="%end_block")
-                    return
-                else if(line=="%variables")
-                    loadVars(lines, variables)
-                else if(line=="%memorypointers")
-                    loadMemoryPointers(lines, memoryPointers, heap)
-                else if(line=="%instructions") {
-                    val (blockInstructions, blockLabels) = loadInstructions(lines, heap)
-                    val baseIndex = program.size
-                    program.addAll(blockInstructions)
-                    val labelsWithIndex = blockLabels.mapValues { baseIndex+blockInstructions.indexOf(it.value) }
-                    labels.putAll(labelsWithIndex)
-                }
-            }
-        }
-
-        private fun loadHeap(lines: Iterator<IndexedValue<String>>, heap: HeapValues) {
-            val splitpattern = Pattern.compile("\\s+")
-            val heapvalues = mutableListOf<Triple<Int, DataType, String>>()
-            while(true) {
-                val (_, line) = lines.next()
-                if (line == "%end_heap")
-                    break
-                val parts = line.split(splitpattern, limit=3)
-                val value = Triple(parts[0].toInt(), DataType.valueOf(parts[1].toUpperCase()), parts[2])
-                heapvalues.add(value)
-            }
-            heapvalues.sortedBy { it.first }.forEach {
-                when(it.second) {
-                    DataType.STR, DataType.STR_S -> heap.addString(it.second, unescape(it.third.substring(1, it.third.length - 1), Position("<stackvmsource>", 0, 0, 0)))
-                    DataType.ARRAY_UB, DataType.ARRAY_B,
-                    DataType.ARRAY_UW, DataType.ARRAY_W -> {
-                        val numbers = it.third.substring(1, it.third.length-1).split(',')
-                        val intarray = numbers.map{number->
-                            val num=number.trim()
-                            if(num.startsWith("&")) {
-                                // it's AddressOf
-                                val scopedname = num.substring(1)
-                                val iref = IdentifierReference(scopedname.split('.'), Position("<intermediate>", 0, 0, 0))
-                                val addrOf = AddressOf(iref, Position("<intermediate>", 0, 0, 0))
-                                addrOf.scopedname=scopedname
-                                IntegerOrAddressOf(null, addrOf)
-                            } else {
-                                IntegerOrAddressOf(num.toInt(), null)
-                            }
-                        }.toTypedArray()
-                        heap.addIntegerArray(it.second, intarray)
-                    }
-                    DataType.ARRAY_F -> {
-                        val numbers = it.third.substring(1, it.third.length-1).split(',')
-                        val doublearray = numbers.map{number->number.trim().toDouble()}.toDoubleArray()
-                        heap.addDoublesArray(doublearray)
-                    }
-                    in NumericDatatypes -> throw VmExecutionException("invalid heap value type ${it.second}")
-                    else -> throw VmExecutionException("weird datatype")
-                }
-            }
-        }
-
-        private fun loadInstructions(lines: Iterator<IndexedValue<String>>, heap: HeapValues): Pair<MutableList<Instruction>, Map<String, Instruction>> {
-            val instructions = mutableListOf<Instruction>()
-            val labels = mutableMapOf<String, Instruction>()
-            val splitpattern = Pattern.compile("\\s+")
-            val nextInstructionLabels = Stack<String>()     // more than one label can occur on the isSameAs line
-
-            while(true) {
-                val (lineNr, line) = lines.next()
-                if(line.isEmpty())
-                    continue
-                if(line=="%end_instructions")
-                    return Pair(instructions, labels)
-                if(!line.startsWith(' ') && line.endsWith(':')) {
-                    nextInstructionLabels.push(line.substring(0, line.length-1))
-                } else if(line.startsWith(' ')) {
-                    val parts = line.trimStart().split(splitpattern, limit = 2)
-                    val opcodeStr = parts[0].toUpperCase()
-                    val opcode= Opcode.valueOf(if(opcodeStr.startsWith('_')) opcodeStr.substring(1) else opcodeStr)
-                    val args = if(parts.size==2) parts[1] else null
-                    val instruction = when(opcode) {
-                        Opcode.LINE -> Instruction(opcode, null, callLabel = args)
-                        Opcode.JUMP, Opcode.CALL, Opcode.BNEG, Opcode.BPOS,
-                        Opcode.BZ, Opcode.BNZ, Opcode.BCS, Opcode.BCC,
-                        Opcode.JZ, Opcode.JNZ, Opcode.JZW, Opcode.JNZW -> {
-                            if(args!!.startsWith('$')) {
-                                Instruction(opcode, RuntimeValue(DataType.UWORD, args.substring(1).toInt(16)))
-                            } else {
-                                Instruction(opcode, callLabel = args)
-                            }
-                        }
-                        in opcodesWithVarArgument -> {
-                            val withoutQuotes =
-                                    if(args!!.startsWith('"') && args.endsWith('"'))
-                                        args.substring(1, args.length-1) else args
-
-                            Instruction(opcode, callLabel = withoutQuotes)
-                        }
-                        Opcode.SYSCALL -> {
-                            if(args!! in syscallNames) {
-                                val call = Syscall.valueOf(args)
-                                Instruction(opcode, RuntimeValue(DataType.UBYTE, call.callNr))
-                            } else {
-                                val args2 = args.replace('.', '_')
-                                if(args2 in syscallNames) {
-                                    val call = Syscall.valueOf(args2)
-                                    Instruction(opcode, RuntimeValue(DataType.UBYTE, call.callNr))
-                                } else {
-                                    // the syscall is not yet implemented. emit a stub.
-                                    Instruction(Opcode.SYSCALL, RuntimeValue(DataType.UBYTE, Syscall.SYSCALLSTUB.callNr), callLabel = args2)
-                                }
-                            }
-                        }
-                        Opcode.INCLUDE_FILE -> {
-                            val argparts = args!!.split(' ')
-                            val filename = argparts[0]
-                            val offset = if(argparts.size>=2 && argparts[1]!="null") getArgValue(argparts[1], heap) else null
-                            val length = if(argparts.size>=3 && argparts[2]!="null") getArgValue(argparts[2], heap) else null
-                            Instruction(opcode, offset, length, filename)
-                        }
-                        else -> {
-                            Instruction(opcode, getArgValue(args, heap))
-                        }
-                    }
-                    instructions.add(instruction)
-                    while(nextInstructionLabels.isNotEmpty()) {
-                        val label = nextInstructionLabels.pop()
-                        labels[label] = instruction
-                    }
-                } else throw VmExecutionException("syntax error at line ${lineNr + 1}")
-            }
-        }
-
-        private fun getArgValue(args: String?, heap: HeapValues): RuntimeValue? {
-            if(args==null)
-                return null
-            if(args[0]=='"' && args[args.length-1]=='"') {
-                throw VmExecutionException("encountered a string arg value, but all strings should already have been moved into the heap")
-            }
-            val (type, valueStr) = args.split(':')
-            return when(type) {
-                "b" -> RuntimeValue(DataType.BYTE, valueStr.toShort(16))
-                "ub" -> RuntimeValue(DataType.UBYTE, valueStr.toShort(16))
-                "w" -> RuntimeValue(DataType.WORD, valueStr.toInt(16))
-                "uw" -> RuntimeValue(DataType.UWORD, valueStr.toInt(16))
-                "f" -> RuntimeValue(DataType.FLOAT, valueStr.toDouble())
-                "heap" -> {
-                    val heapId = valueStr.toInt()
-                    RuntimeValue(heap.get(heapId).type, heapId = heapId)
-                }
-                else -> throw VmExecutionException("invalid datatype $type")
-            }
-        }
-
-        private fun loadVars(lines: Iterator<IndexedValue<String>>,
-                             vars: MutableMap<String, RuntimeValue>) {
-            val splitpattern = Pattern.compile("\\s+")
-            while(true) {
-                val (_, line) = lines.next()
-                if(line=="%end_variables")
-                    return
-                val (name, typeStr, valueStr) = line.split(splitpattern, limit = 3)
-                if(valueStr[0] !='"' && ':' !in valueStr)
-                    throw VmExecutionException("missing value type character")
-                val value = when(val type = DataType.valueOf(typeStr.toUpperCase())) {
-                    DataType.UBYTE -> RuntimeValue(DataType.UBYTE, valueStr.substring(3).substringBefore(' ').toShort(16))// TODO process ZP and struct info?
-                    DataType.BYTE -> RuntimeValue(DataType.BYTE, valueStr.substring(2).substringBefore(' ').toShort(16))// TODO process ZP and struct info?
-                    DataType.UWORD -> RuntimeValue(DataType.UWORD, valueStr.substring(3).substringBefore(' ').toInt(16))// TODO process ZP and struct info?
-                    DataType.WORD -> RuntimeValue(DataType.WORD, valueStr.substring(2).substringBefore(' ').toInt(16))// TODO process ZP and struct info?
-                    DataType.FLOAT -> RuntimeValue(DataType.FLOAT, valueStr.substring(2).substringBefore(' ').toDouble())// TODO process ZP and struct info?
-                    in StringDatatypes -> {
-                        if(valueStr.startsWith('"') && valueStr.endsWith('"'))
-                            throw VmExecutionException("encountered a var with a string value, but all string values should already have been moved into the heap")
-                        else if(!valueStr.startsWith("heap:"))
-                            throw VmExecutionException("invalid string value, should be a heap reference")
-                        else {
-                            val heapId = valueStr.substring(5).substringBefore(' ').toInt()     // TODO process ZP and struct info?
-                            RuntimeValue(type, heapId = heapId)
-                        }
-                    }
-                    in ArrayDatatypes -> {
-                        if(!valueStr.startsWith("heap:"))
-                            throw VmExecutionException("invalid array value, should be a heap reference")
-                        else {
-                            val heapId = valueStr.substring(5).substringBefore(' ').toInt()     // TODO process ZP and struct info?
-                            RuntimeValue(type, heapId = heapId)
-                        }
-                    }
-                    else -> throw VmExecutionException("weird datatype")
-                }
-                vars[name] = value
-            }
-        }
-
-        private fun loadMemoryPointers(lines: Iterator<IndexedValue<String>>,
-                                       pointers: MutableMap<String, Pair<Int, DataType>>,
-                                       heap: HeapValues) {
-            val splitpattern = Pattern.compile("\\s+")
-            while(true) {
-                val (_, line) = lines.next()
-                if(line=="%end_memorypointers")
-                    return
-                val (name, typeStr, valueStr) = line.split(splitpattern, limit = 3)
-                if(valueStr[0] !='"' && ':' !in valueStr)
-                    throw VmExecutionException("missing value type character")
-                val type = DataType.valueOf(typeStr.toUpperCase())
-                val value = getArgValue(valueStr, heap)!!.integerValue()
-                pointers[name] = Pair(value, type)
-            }
-        }
-
-        private fun loadMemory(lines: Iterator<IndexedValue<String>>, memory: MutableMap<Int, List<RuntimeValue>>): Map<Int, List<RuntimeValue>> {
-            while(true) {
-                val (lineNr, line) = lines.next()
-                if(line=="%end_memory")
-                    return memory
-                val address = line.substringBefore(' ').toInt(16)
-                val rest = line.substringAfter(' ').trim()
-                if(rest.startsWith('"')) {
-                    TODO("memory init with char/string")
-                } else {
-                    val valueStrings = rest.split(' ')
-                    val values = mutableListOf<RuntimeValue>()
-                    valueStrings.forEach {
-                        when(it.length) {
-                            2 -> values.add(RuntimeValue(DataType.UBYTE, it.toShort(16)))
-                            4 -> values.add(RuntimeValue(DataType.UWORD, it.toInt(16)))
-                            else -> throw VmExecutionException("invalid value at line $lineNr+1")
-                        }
-                    }
-                    memory[address] = values
-                }
-            }
-        }
-    }
-}

README.md

@@ -1,5 +1,6 @@
 [![saythanks](https://img.shields.io/badge/say-thanks-ff69b4.svg)](https://saythanks.io/to/irmen)
 [![Build Status](https://travis-ci.org/irmen/prog8.svg?branch=master)](https://travis-ci.org/irmen/prog8)
+[![Documentation](https://readthedocs.org/projects/prog8/badge/?version=latest)](https://prog8.readthedocs.io/)
 
 Prog8 - Structured Programming Language for 8-bit 6502/6510 microprocessors
 ===========================================================================
@@ -14,40 +15,34 @@ as used in many home computers from that era. It is a medium to low level progra
 which aims to provide many conveniences over raw assembly code (even when using a macro assembler):
 
 - reduction of source code length
-- easier program understanding (because it's higher level, and way more compact)
 - modularity, symbol scoping, subroutines
-- subroutines have enforced input- and output parameter definitions
 - various data types other than just bytes (16-bit words, floats, strings)
-- automatic variable allocations, automatic string variables and string sharing
-- constant folding in expressions (compile-time evaluation)
+- automatic variable allocations, automatic string and array variables and string sharing
+- subroutines with an input- and output parameter signature
+- constant folding in expressions
 - conditional branches
-- when statement to provide a 'jump table' alternative to if/elseif chains
+- 'when' statement to provide a concise jump table alternative to if/elseif chains
 - structs to group together sets of variables and manipulate them at once
-- automatic type conversions
-- floating point operations  (uses the C64 Basic ROM routines for this)
+- floating point operations  (requires the C64 Basic ROM routines for this)
 - abstracting away low level aspects such as ZeroPage handling, program startup, explicit memory addresses
 - various code optimizations (code structure, logical and numerical expressions, unused code removal...)
 - inline assembly allows you to have full control when every cycle or byte matters
- 
+- many built-in functions such as ``sin``, ``cos``, ``rnd``, ``abs``, ``min``, ``max``, ``sqrt``, ``msb``, ``rol``, ``ror``, ``swap``, ``memset``, ``memcopy``, ``sort`` and ``reverse``
 
 Rapid edit-compile-run-debug cycle:
 
-- use modern PC to work on 
-- quick compilation times (around a second, and less than 0.1 seconds when using the continuous compilation mode)
-- option to automatically run the program in the Vice emulator  
+- use a modern PC to do the work on
+- very quick compilation times
+- can automatically run the program in the Vice emulator after succesful compilation
 - breakpoints, that let the Vice emulator drop into the monitor if execution hits them
 - source code labels automatically loaded in Vice emulator so it can show them in disassembly
-- the compiler includes a virtual machine that can execute compiled code directy on the
-  host system without having to actually convert it to assembly to run on a real 6502. 
-  This allows for very quick experimentation and debugging
 
-It is mainly targeted at the Commodore-64 machine at this time.
+Prog8 is mainly targeted at the Commodore-64 machine at this time.
 Contributions to add support for other 8-bit (or other?!) machines are welcome.
 
 Documentation/manual
 --------------------
-See https://prog8.readthedocs.io/
-
+https://prog8.readthedocs.io/
 
 Required tools
 --------------
@@ -82,7 +77,7 @@ This code calculates prime numbers using the Sieve of Eratosthenes algorithm::
 
             c64scr.print("prime numbers up to 255:\n\n")
             ubyte amount=0
-            while true {
+            repeat {
                 ubyte prime = find_next_prime()
                 if prime==0
                     break

compiler/build.gradle

@@ -1,54 +1,62 @@
 buildscript {
     dependencies {
-        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlinVersion"
+        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:1.4.0"
     }
 }
 
 plugins {
-    // id "org.jetbrains.kotlin.jvm" version $kotlinVersion
+    // id "org.jetbrains.kotlin.jvm" version "1.4.0"
     id 'application'
     id 'org.jetbrains.dokka' version "0.9.18"
-    id 'com.github.johnrengelman.shadow' version '5.1.0'
+    id 'com.github.johnrengelman.shadow' version '5.2.0'
     id 'java'
 }
 
 apply plugin: "kotlin"
 apply plugin: "java"
 
+targetCompatibility = 1.8
+sourceCompatibility = 1.8
 
 repositories {
     mavenLocal()
     mavenCentral()
     jcenter()
+    maven { url "https://dl.bintray.com/orangy/maven/" }
 }
 
-sourceCompatibility = 1.8
-
 def prog8version = rootProject.file('compiler/res/version.txt').text.trim()
 
 dependencies {
     implementation project(':parser')
-    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8:$kotlinVersion"
-    // implementation "org.jetbrains.kotlin:kotlin-reflect:$kotlinVersion"
-    // runtime "org.jetbrains.kotlin:kotlin-reflect:$kotlinVersion"
-    runtime 'org.antlr:antlr4-runtime:4.7.2'
-    runtime project(':parser')
+    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8"
+    // implementation "org.jetbrains.kotlin:kotlin-reflect"
+    implementation 'org.antlr:antlr4-runtime:4.8'
+    implementation 'org.jetbrains.kotlinx:kotlinx-cli-jvm:0.1.0-dev-5'
+    // implementation 'net.razorvine:ksim65:1.6'
+    // implementation "com.github.hypfvieh:dbus-java:3.2.0"
+    implementation project(':parser')
 
-    testImplementation "org.jetbrains.kotlin:kotlin-test-junit5:$kotlinVersion"
+    testImplementation "org.jetbrains.kotlin:kotlin-test-junit5"
     testImplementation 'org.junit.jupiter:junit-jupiter-api:5.3.2'
     testImplementation 'org.hamcrest:hamcrest-junit:2.0.0.0'
-
     testRuntimeOnly 'org.junit.jupiter:junit-jupiter-engine:5.3.2'
 }
 
 compileKotlin {
     kotlinOptions {
         jvmTarget = "1.8"
-        verbose = true
+        // verbose = true
         // freeCompilerArgs += "-XXLanguage:+NewInference"
     }
 }
 
+compileTestKotlin {
+    kotlinOptions {
+        jvmTarget = "1.8"
+    }
+}
+
 sourceSets {
     main {
         java {
@@ -77,12 +85,9 @@ artifacts {
 }
 
 
-// To create a fat-jar use the 'create_compiler_jar' script for now
-// @todo investigate https://imperceptiblethoughts.com/shadow/introduction/
-
 shadowJar {
-    baseName = 'prog8compiler'
-    version = prog8version
+    archiveBaseName = 'prog8compiler'
+    archiveVersion = prog8version
     // minimize()
 }
 
@@ -96,7 +101,7 @@ test {
 
     // Show test results.
     testLogging {
-        events "passed", "skipped", "failed"
+        events "skipped", "failed"
     }
 }
 
@@ -105,3 +110,7 @@ dokka {
     outputFormat = 'html'
     outputDirectory = "$buildDir/kdoc"
 }
+
+task wrapper(type: Wrapper) {
+    gradleVersion = '6.1.1'
+}

compiler/compiler.iml

@@ -8,11 +8,12 @@
       <sourceFolder url="file://$MODULE_DIR$/test" isTestSource="true" />
       <excludeFolder url="file://$MODULE_DIR$/build" />
     </content>
-    <orderEntry type="jdk" jdkName="1.8" jdkType="JavaSDK" />
+    <orderEntry type="jdk" jdkName="openjdk-11" jdkType="JavaSDK" />
     <orderEntry type="sourceFolder" forTests="false" />
     <orderEntry type="library" name="KotlinJavaRuntime" level="project" />
-    <orderEntry type="library" name="antlr-runtime-4.7.2" level="project" />
     <orderEntry type="module" module-name="parser" />
     <orderEntry type="library" name="unittest-libs" level="project" />
+    <orderEntry type="library" name="kotlinx-cli-jvm-0.1.0-dev-5" level="project" />
+    <orderEntry type="library" name="antlr-runtime-4.8" level="project" />
   </component>
 </module>

compiler/res/prog8lib/c64floats.asm

@@ -0,0 +1,787 @@
+; --- low level floating point assembly routines for the C64
+
+ub2float	.proc
+		; -- convert ubyte in SCRATCH_ZPB1 to float at address A/Y
+		;    clobbers A, Y
+		stx  c64.SCRATCH_ZPREGX
+		sta  c64.SCRATCH_ZPWORD2
+		sty  c64.SCRATCH_ZPWORD2+1
+		ldy  c64.SCRATCH_ZPB1
+		jsr  FREADUY
+_fac_to_mem	ldx  c64.SCRATCH_ZPWORD2
+		ldy  c64.SCRATCH_ZPWORD2+1
+		jsr  MOVMF
+		ldx  c64.SCRATCH_ZPREGX
+		rts
+		.pend
+
+b2float		.proc
+		; -- convert byte in SCRATCH_ZPB1 to float at address A/Y
+		;    clobbers A, Y
+		stx  c64.SCRATCH_ZPREGX
+		sta  c64.SCRATCH_ZPWORD2
+		sty  c64.SCRATCH_ZPWORD2+1
+		lda  c64.SCRATCH_ZPB1
+		jsr  FREADSA
+		jmp  ub2float._fac_to_mem
+		.pend
+
+uw2float	.proc
+		; -- convert uword in SCRATCH_ZPWORD1 to float at address A/Y
+		stx  c64.SCRATCH_ZPREGX
+		sta  c64.SCRATCH_ZPWORD2
+		sty  c64.SCRATCH_ZPWORD2+1
+		lda  c64.SCRATCH_ZPWORD1
+		ldy  c64.SCRATCH_ZPWORD1+1
+		jsr  GIVUAYFAY
+		jmp  ub2float._fac_to_mem
+		.pend
+
+w2float		.proc
+		; -- convert word in SCRATCH_ZPWORD1 to float at address A/Y
+		stx  c64.SCRATCH_ZPREGX
+		sta  c64.SCRATCH_ZPWORD2
+		sty  c64.SCRATCH_ZPWORD2+1
+		ldy  c64.SCRATCH_ZPWORD1
+		lda  c64.SCRATCH_ZPWORD1+1
+		jsr  GIVAYF
+		jmp  ub2float._fac_to_mem
+		.pend
+
+stack_b2float	.proc
+		; -- b2float operating on the stack
+		inx
+		lda  c64.ESTACK_LO,x
+		stx  c64.SCRATCH_ZPREGX
+		jsr  FREADSA
+		jmp  push_fac1_as_result
+		.pend
+
+stack_w2float	.proc
+		; -- w2float operating on the stack
+		inx
+		ldy  c64.ESTACK_LO,x
+		lda  c64.ESTACK_HI,x
+		stx  c64.SCRATCH_ZPREGX
+		jsr  GIVAYF
+		jmp  push_fac1_as_result
+		.pend
+
+stack_ub2float	.proc
+		; -- ub2float operating on the stack
+		inx
+		lda  c64.ESTACK_LO,x
+		stx  c64.SCRATCH_ZPREGX
+		tay
+		jsr  FREADUY
+		jmp  push_fac1_as_result
+		.pend
+
+stack_uw2float	.proc
+		; -- uw2float operating on the stack
+		inx
+		lda  c64.ESTACK_LO,x
+		ldy  c64.ESTACK_HI,x
+		stx  c64.SCRATCH_ZPREGX
+		jsr  GIVUAYFAY
+		jmp  push_fac1_as_result
+		.pend
+
+stack_float2w	.proc               ; also used for float2b
+		jsr  pop_float_fac1
+		stx  c64.SCRATCH_ZPREGX
+		jsr  AYINT
+		ldx  c64.SCRATCH_ZPREGX
+		lda  $64
+		sta  c64.ESTACK_HI,x
+		lda  $65
+		sta  c64.ESTACK_LO,x
+		dex
+		rts
+		.pend
+
+stack_float2uw	.proc               ; also used for float2ub
+		jsr  pop_float_fac1
+		stx  c64.SCRATCH_ZPREGX
+		jsr  GETADR
+		ldx  c64.SCRATCH_ZPREGX
+		sta  c64.ESTACK_HI,x
+		tya
+		sta  c64.ESTACK_LO,x
+		dex
+		rts
+		.pend
+
+push_float	.proc
+		; ---- push mflpt5 in A/Y onto stack
+		; (taking 3 stack positions = 6 bytes of which 1 is padding)
+		sta  c64.SCRATCH_ZPWORD1
+		sty  c64.SCRATCH_ZPWORD1+1
+		ldy  #0
+		lda  (c64.SCRATCH_ZPWORD1),y
+		sta  c64.ESTACK_LO,x
+		iny
+		lda  (c64.SCRATCH_ZPWORD1),y
+		sta  c64.ESTACK_HI,x
+		dex
+		iny
+		lda  (c64.SCRATCH_ZPWORD1),y
+		sta  c64.ESTACK_LO,x
+		iny
+		lda  (c64.SCRATCH_ZPWORD1),y
+		sta  c64.ESTACK_HI,x
+		dex
+		iny
+		lda  (c64.SCRATCH_ZPWORD1),y
+		sta  c64.ESTACK_LO,x
+		dex
+		rts
+		.pend
+
+func_rndf	.proc
+		; -- put a random floating point value on the stack
+		stx  c64.SCRATCH_ZPREG
+		lda  #1
+		jsr  FREADSA
+		jsr  RND		; rng into fac1
+		ldx  #<_rndf_rnum5
+		ldy  #>_rndf_rnum5
+		jsr  MOVMF	; fac1 to mem X/Y
+		ldx  c64.SCRATCH_ZPREG
+		lda  #<_rndf_rnum5
+		ldy  #>_rndf_rnum5
+		jmp  push_float
+_rndf_rnum5	.byte  0,0,0,0,0
+		.pend
+
+push_float_from_indexed_var	.proc
+		; -- push the float from the array at A/Y with index on stack, onto the stack.
+		sta  c64.SCRATCH_ZPWORD1
+		sty  c64.SCRATCH_ZPWORD1+1
+		jsr  prog8_lib.pop_index_times_5
+		jsr  prog8_lib.add_a_to_zpword
+		lda  c64.SCRATCH_ZPWORD1
+		ldy  c64.SCRATCH_ZPWORD1+1
+		jmp  push_float
+		.pend
+
+pop_float	.proc
+		; ---- pops mflpt5 from stack to memory A/Y
+		; (frees 3 stack positions = 6 bytes of which 1 is padding)
+		sta  c64.SCRATCH_ZPWORD1
+		sty  c64.SCRATCH_ZPWORD1+1
+		ldy  #4
+		inx
+		lda  c64.ESTACK_LO,x
+		sta  (c64.SCRATCH_ZPWORD1),y
+		dey
+		inx
+		lda  c64.ESTACK_HI,x
+		sta  (c64.SCRATCH_ZPWORD1),y
+		dey
+		lda  c64.ESTACK_LO,x
+		sta  (c64.SCRATCH_ZPWORD1),y
+		dey
+		inx
+		lda  c64.ESTACK_HI,x
+		sta  (c64.SCRATCH_ZPWORD1),y
+		dey
+		lda  c64.ESTACK_LO,x
+		sta  (c64.SCRATCH_ZPWORD1),y
+		rts
+		.pend
+
+pop_float_fac1	.proc
+		; -- pops float from stack into FAC1
+		lda  #<fmath_float1
+		ldy  #>fmath_float1
+		jsr  pop_float
+		lda  #<fmath_float1
+		ldy  #>fmath_float1
+		jmp  MOVFM
+		.pend
+
+pop_float_to_indexed_var	.proc
+		; -- pop the float on the stack, to the memory in the array at A/Y indexed by the byte on stack
+		sta  c64.SCRATCH_ZPWORD1
+		sty  c64.SCRATCH_ZPWORD1+1
+		jsr  prog8_lib.pop_index_times_5
+		jsr  prog8_lib.add_a_to_zpword
+		lda  c64.SCRATCH_ZPWORD1
+		ldy  c64.SCRATCH_ZPWORD1+1
+		jmp  pop_float
+		.pend
+
+copy_float	.proc
+		; -- copies the 5 bytes of the mflt value pointed to by SCRATCH_ZPWORD1,
+		;    into the 5 bytes pointed to by A/Y.  Clobbers A,Y.
+		sta  _target+1
+		sty  _target+2
+		ldy  #4
+_loop		lda  (c64.SCRATCH_ZPWORD1),y
+_target		sta  $ffff,y			; modified
+		dey
+		bpl  _loop
+		rts
+		.pend
+
+inc_var_f	.proc
+		; -- add 1 to float pointed to by A/Y
+		sta  c64.SCRATCH_ZPWORD1
+		sty  c64.SCRATCH_ZPWORD1+1
+		stx  c64.SCRATCH_ZPREGX
+		jsr  MOVFM
+		lda  #<FL_FONE
+		ldy  #>FL_FONE
+		jsr  FADD
+		ldx  c64.SCRATCH_ZPWORD1
+		ldy  c64.SCRATCH_ZPWORD1+1
+		jsr  MOVMF
+		ldx  c64.SCRATCH_ZPREGX
+		rts
+		.pend
+
+dec_var_f	.proc
+		; -- subtract 1 from float pointed to by A/Y
+		sta  c64.SCRATCH_ZPWORD1
+		sty  c64.SCRATCH_ZPWORD1+1
+		stx  c64.SCRATCH_ZPREGX
+		lda  #<FL_FONE
+		ldy  #>FL_FONE
+		jsr  MOVFM
+		lda  c64.SCRATCH_ZPWORD1
+		ldy  c64.SCRATCH_ZPWORD1+1
+		jsr  FSUB
+		ldx  c64.SCRATCH_ZPWORD1
+		ldy  c64.SCRATCH_ZPWORD1+1
+		jsr  MOVMF
+		ldx  c64.SCRATCH_ZPREGX
+		rts
+		.pend
+
+inc_indexed_var_f	.proc
+		; -- add 1 to float in array pointed to by A/Y, at index X
+		pha
+		txa
+		sta  c64.SCRATCH_ZPB1
+		asl  a
+		asl  a
+		clc
+		adc  c64.SCRATCH_ZPB1
+		sta  c64.SCRATCH_ZPB1
+		pla
+		clc
+		adc  c64.SCRATCH_ZPB1
+		bcc  +
+		iny
++		jmp  inc_var_f
+		.pend
+
+dec_indexed_var_f	.proc
+		; -- subtract 1 to float in array pointed to by A/Y, at index X
+		pha
+		txa
+		sta  c64.SCRATCH_ZPB1
+		asl  a
+		asl  a
+		clc
+		adc  c64.SCRATCH_ZPB1
+		sta  c64.SCRATCH_ZPB1
+		pla
+		clc
+		adc  c64.SCRATCH_ZPB1
+		bcc  +
+		iny
++		jmp  dec_var_f
+		.pend
+
+
+pop_2_floats_f2_in_fac1	.proc
+		; -- pop 2 floats from stack, load the second one in FAC1 as well
+		lda  #<fmath_float2
+		ldy  #>fmath_float2
+		jsr  pop_float
+		lda  #<fmath_float1
+		ldy  #>fmath_float1
+		jsr  pop_float
+		lda  #<fmath_float2
+		ldy  #>fmath_float2
+		jmp  MOVFM
+		.pend
+
+
+fmath_float1	.byte 0,0,0,0,0	; storage for a mflpt5 value
+fmath_float2	.byte 0,0,0,0,0	; storage for a mflpt5 value
+
+push_fac1_as_result	.proc
+		; -- push the float in FAC1 onto the stack, and return from calculation
+		ldx  #<fmath_float1
+		ldy  #>fmath_float1
+		jsr  MOVMF
+		lda  #<fmath_float1
+		ldy  #>fmath_float1
+		ldx  c64.SCRATCH_ZPREGX
+		jmp  push_float
+		.pend
+
+pow_f		.proc
+		; -- push f1 ** f2 on stack
+		lda  #<fmath_float2
+		ldy  #>fmath_float2
+		jsr  pop_float
+		lda  #<fmath_float1
+		ldy  #>fmath_float1
+		jsr  pop_float
+		stx  c64.SCRATCH_ZPREGX
+		lda  #<fmath_float1
+		ldy  #>fmath_float1
+		jsr  CONUPK		; fac2 = float1
+		lda  #<fmath_float2
+		ldy  #>fmath_float2
+		jsr  FPWR
+		ldx  c64.SCRATCH_ZPREGX
+		jmp  push_fac1_as_result
+		.pend
+
+div_f		.proc
+		; -- push f1/f2 on stack
+		jsr  pop_2_floats_f2_in_fac1
+		stx  c64.SCRATCH_ZPREGX
+		lda  #<fmath_float1
+		ldy  #>fmath_float1
+		jsr  FDIV
+		jmp  push_fac1_as_result
+		.pend
+
+add_f		.proc
+		; -- push f1+f2 on stack
+		jsr  pop_2_floats_f2_in_fac1
+		stx  c64.SCRATCH_ZPREGX
+		lda  #<fmath_float1
+		ldy  #>fmath_float1
+		jsr  FADD
+		jmp  push_fac1_as_result
+		.pend
+
+sub_f		.proc
+		; -- push f1-f2 on stack
+		jsr  pop_2_floats_f2_in_fac1
+		stx  c64.SCRATCH_ZPREGX
+		lda  #<fmath_float1
+		ldy  #>fmath_float1
+		jsr  FSUB
+		jmp  push_fac1_as_result
+		.pend
+
+mul_f		.proc
+		; -- push f1*f2 on stack
+		jsr  pop_2_floats_f2_in_fac1
+		stx  c64.SCRATCH_ZPREGX
+		lda  #<fmath_float1
+		ldy  #>fmath_float1
+		jsr  FMULT
+		jmp  push_fac1_as_result
+		.pend
+
+neg_f		.proc
+		; -- push -flt back on stack
+		jsr  pop_float_fac1
+		stx  c64.SCRATCH_ZPREGX
+		jsr  NEGOP
+		jmp  push_fac1_as_result
+		.pend
+
+abs_f		.proc
+		; -- push abs(float) on stack (as float)
+		jsr  pop_float_fac1
+		stx  c64.SCRATCH_ZPREGX
+		jsr  ABS
+		jmp  push_fac1_as_result
+		.pend
+
+equal_f		.proc
+		; -- are the two mflpt5 numbers on the stack identical?
+		inx
+		inx
+		inx
+		inx
+		lda  c64.ESTACK_LO-3,x
+		cmp  c64.ESTACK_LO,x
+		bne  _equals_false
+		lda  c64.ESTACK_LO-2,x
+		cmp  c64.ESTACK_LO+1,x
+		bne  _equals_false
+		lda  c64.ESTACK_LO-1,x
+		cmp  c64.ESTACK_LO+2,x
+		bne  _equals_false
+		lda  c64.ESTACK_HI-2,x
+		cmp  c64.ESTACK_HI+1,x
+		bne  _equals_false
+		lda  c64.ESTACK_HI-1,x
+		cmp  c64.ESTACK_HI+2,x
+		bne  _equals_false
+_equals_true	lda  #1
+_equals_store	inx
+		sta  c64.ESTACK_LO+1,x
+		rts
+_equals_false	lda  #0
+		beq  _equals_store
+		.pend
+
+notequal_f	.proc
+		; -- are the two mflpt5 numbers on the stack different?
+		jsr  equal_f
+		eor  #1		; invert the result
+		sta  c64.ESTACK_LO+1,x
+		rts
+		.pend
+
+less_f		.proc
+		; -- is f1 < f2?
+		jsr  compare_floats
+		cmp  #255
+		beq  compare_floats._return_true
+		bne  compare_floats._return_false
+		.pend
+
+
+lesseq_f	.proc
+		; -- is f1 <= f2?
+		jsr  compare_floats
+		cmp  #255
+		beq  compare_floats._return_true
+		cmp  #0
+		beq  compare_floats._return_true
+		bne  compare_floats._return_false
+		.pend
+
+greater_f	.proc
+		; -- is f1 > f2?
+		jsr  compare_floats
+		cmp  #1
+		beq  compare_floats._return_true
+		bne  compare_floats._return_false
+		.pend
+
+greatereq_f	.proc
+		; -- is f1 >= f2?
+		jsr  compare_floats
+		cmp  #1
+		beq  compare_floats._return_true
+		cmp  #0
+		beq  compare_floats._return_true
+		bne  compare_floats._return_false
+		.pend
+
+compare_floats	.proc
+		lda  #<fmath_float2
+		ldy  #>fmath_float2
+		jsr  pop_float
+		lda  #<fmath_float1
+		ldy  #>fmath_float1
+		jsr  pop_float
+		lda  #<fmath_float1
+		ldy  #>fmath_float1
+		jsr  MOVFM		; fac1 = flt1
+		lda  #<fmath_float2
+		ldy  #>fmath_float2
+		stx  c64.SCRATCH_ZPREG
+		jsr  FCOMP		; A = flt1 compared with flt2 (0=equal, 1=flt1>flt2, 255=flt1<flt2)
+		ldx  c64.SCRATCH_ZPREG
+		rts
+_return_false	lda  #0
+_return_result  sta  c64.ESTACK_LO,x
+		dex
+		rts
+_return_true	lda  #1
+		bne  _return_result
+		.pend
+
+func_sin	.proc
+		; -- push sin(f) back onto stack
+		jsr  pop_float_fac1
+		stx  c64.SCRATCH_ZPREGX
+		jsr  SIN
+		jmp  push_fac1_as_result
+		.pend
+
+func_cos	.proc
+		; -- push cos(f) back onto stack
+		jsr  pop_float_fac1
+		stx  c64.SCRATCH_ZPREGX
+		jsr  COS
+		jmp  push_fac1_as_result
+		.pend
+
+func_tan	.proc
+		; -- push tan(f) back onto stack
+		jsr  pop_float_fac1
+		stx  c64.SCRATCH_ZPREGX
+		jsr  TAN
+		jmp  push_fac1_as_result
+		.pend
+
+func_atan	.proc
+		; -- push atan(f) back onto stack
+		jsr  pop_float_fac1
+		stx  c64.SCRATCH_ZPREGX
+		jsr  ATN
+		jmp  push_fac1_as_result
+		.pend
+
+func_ln		.proc
+		; -- push ln(f) back onto stack
+		jsr  pop_float_fac1
+		stx  c64.SCRATCH_ZPREGX
+		jsr  LOG
+		jmp  push_fac1_as_result
+		.pend
+
+func_log2	.proc
+		; -- push log base 2, ln(f)/ln(2), back onto stack
+		jsr  pop_float_fac1
+		stx  c64.SCRATCH_ZPREGX
+		jsr  LOG
+		jsr  MOVEF
+		lda  #<c64.FL_LOG2
+		ldy  #>c64.FL_LOG2
+		jsr  MOVFM
+		jsr  FDIVT
+		jmp  push_fac1_as_result
+		.pend
+
+func_sqrt	.proc
+		jsr  pop_float_fac1
+		stx  c64.SCRATCH_ZPREGX
+		jsr  SQR
+		jmp  push_fac1_as_result
+		.pend
+
+func_rad	.proc
+		; -- convert degrees to radians (d * pi / 180)
+		jsr  pop_float_fac1
+		stx  c64.SCRATCH_ZPREGX
+		lda  #<_pi_div_180
+		ldy  #>_pi_div_180
+		jsr  FMULT
+		jmp  push_fac1_as_result
+_pi_div_180	.byte 123, 14, 250, 53, 18		; pi / 180
+		.pend
+
+func_deg	.proc
+		; -- convert radians to degrees (d * (1/ pi * 180))
+		jsr  pop_float_fac1
+		stx  c64.SCRATCH_ZPREGX
+		lda  #<_one_over_pi_div_180
+		ldy  #>_one_over_pi_div_180
+		jsr  FMULT
+		jmp  push_fac1_as_result
+_one_over_pi_div_180	.byte 134, 101, 46, 224, 211		; 1 / (pi * 180)
+		.pend
+
+func_round	.proc
+		jsr  pop_float_fac1
+		stx  c64.SCRATCH_ZPREGX
+		jsr  FADDH
+		jsr  INT
+		jmp  push_fac1_as_result
+		.pend
+
+func_floor	.proc
+		jsr  pop_float_fac1
+		stx  c64.SCRATCH_ZPREGX
+		jsr  INT
+		jmp  push_fac1_as_result
+		.pend
+
+func_ceil	.proc
+		; -- ceil: tr = int(f); if tr==f -> return  else return tr+1
+		jsr  pop_float_fac1
+		stx  c64.SCRATCH_ZPREGX
+		ldx  #<fmath_float1
+		ldy  #>fmath_float1
+		jsr  MOVMF
+		jsr  INT
+		lda  #<fmath_float1
+		ldy  #>fmath_float1
+		jsr  FCOMP
+		cmp  #0
+		beq  +
+		lda  #<FL_FONE
+		ldy  #>FL_FONE
+		jsr  FADD
++		jmp  push_fac1_as_result
+		.pend
+
+func_any_f	.proc
+		inx
+		lda  c64.ESTACK_LO,x	; array size
+		sta  c64.SCRATCH_ZPB1
+		asl  a
+		asl  a
+		clc
+		adc  c64.SCRATCH_ZPB1	; times 5 because of float
+		jmp  prog8_lib.func_any_b._entry
+		.pend
+
+func_all_f	.proc
+		inx
+		jsr  prog8_lib.peek_address
+		lda  c64.ESTACK_LO,x	; array size
+		sta  c64.SCRATCH_ZPB1
+		asl  a
+		asl  a
+		clc
+		adc  c64.SCRATCH_ZPB1	; times 5 because of float
+		tay
+		dey
+-		lda  (c64.SCRATCH_ZPWORD1),y
+		clc
+		dey
+		adc  (c64.SCRATCH_ZPWORD1),y
+		dey
+		adc  (c64.SCRATCH_ZPWORD1),y
+		dey
+		adc  (c64.SCRATCH_ZPWORD1),y
+		dey
+		adc  (c64.SCRATCH_ZPWORD1),y
+		dey
+		cmp  #0
+		beq  +
+		cpy  #255
+        	bne  -
+		lda  #1
+		sta  c64.ESTACK_LO+1,x
+		rts
++		sta  c64.ESTACK_LO+1,x
+		rts
+		.pend
+
+func_max_f	.proc
+		lda  #255
+		sta  _minmax_cmp+1
+		lda  #<_largest_neg_float
+		ldy  #>_largest_neg_float
+_minmax_entry	jsr  MOVFM
+		jsr  prog8_lib.pop_array_and_lengthmin1Y
+		stx  c64.SCRATCH_ZPREGX
+-		sty  c64.SCRATCH_ZPREG
+		lda  c64.SCRATCH_ZPWORD1
+		ldy  c64.SCRATCH_ZPWORD1+1
+		jsr  FCOMP
+_minmax_cmp	cmp  #255			; modified
+		bne  +
+		lda  c64.SCRATCH_ZPWORD1
+		ldy  c64.SCRATCH_ZPWORD1+1
+		jsr  MOVFM
++		lda  c64.SCRATCH_ZPWORD1
+		clc
+		adc  #5
+		sta  c64.SCRATCH_ZPWORD1
+		bcc  +
+		inc  c64.SCRATCH_ZPWORD1+1
++		ldy  c64.SCRATCH_ZPREG
+		dey
+		cpy  #255
+		bne  -
+		jmp  push_fac1_as_result
+_largest_neg_float	.byte 255,255,255,255,255		; largest negative float -1.7014118345e+38
+		.pend
+
+func_min_f	.proc
+		lda  #1
+		sta  func_max_f._minmax_cmp+1
+		lda  #<_largest_pos_float
+		ldy  #>_largest_pos_float
+		jmp  func_max_f._minmax_entry
+_largest_pos_float	.byte  255,127,255,255,255		; largest positive float
+		rts
+		.pend
+
+func_sum_f	.proc
+		lda  #<FL_ZERO
+		ldy  #>FL_ZERO
+		jsr  MOVFM
+		jsr  prog8_lib.pop_array_and_lengthmin1Y
+		stx  c64.SCRATCH_ZPREGX
+-		sty  c64.SCRATCH_ZPREG
+		lda  c64.SCRATCH_ZPWORD1
+		ldy  c64.SCRATCH_ZPWORD1+1
+		jsr  FADD
+		ldy  c64.SCRATCH_ZPREG
+		dey
+		cpy  #255
+		beq  +
+		lda  c64.SCRATCH_ZPWORD1
+		clc
+		adc  #5
+		sta  c64.SCRATCH_ZPWORD1
+		bcc  -
+		inc  c64.SCRATCH_ZPWORD1+1
+		bne  -
++		jmp  push_fac1_as_result
+		.pend
+
+sign_f		.proc
+		jsr  pop_float_fac1
+		jsr  SIGN
+		sta  c64.ESTACK_LO,x
+		dex
+		rts
+		.pend
+
+
+set_0_array_float	.proc
+		; -- set a float in an array to zero (index on stack, array in SCRATCH_ZPWORD1)
+		inx
+		lda  c64.ESTACK_LO,x
+		asl  a
+		asl  a
+		clc
+		adc  c64.ESTACK_LO,x
+		tay
+		lda  #0
+		sta  (c64.SCRATCH_ZPWORD1),y
+		iny
+		sta  (c64.SCRATCH_ZPWORD1),y
+		iny
+		sta  (c64.SCRATCH_ZPWORD1),y
+		iny
+		sta  (c64.SCRATCH_ZPWORD1),y
+		iny
+		sta  (c64.SCRATCH_ZPWORD1),y
+		rts
+		.pend
+
+
+set_array_float		.proc
+		; -- set a float in an array to a value (index on stack, float in SCRATCH_ZPWORD1, array in SCRATCH_ZPWORD2)
+		inx
+		lda  c64.ESTACK_LO,x
+		asl  a
+		asl  a
+		clc
+		adc  c64.ESTACK_LO,x
+		adc  c64.SCRATCH_ZPWORD2
+		ldy  c64.SCRATCH_ZPWORD2+1
+		bcc  +
+		iny
++		jmp  copy_float
+			; -- copies the 5 bytes of the mflt value pointed to by SCRATCH_ZPWORD1,
+			;    into the 5 bytes pointed to by A/Y.  Clobbers A,Y.
+		.pend
+
+
+swap_floats	.proc
+		; -- swap floats pointed to by SCRATCH_ZPWORD1, SCRATCH_ZPWORD2
+		ldy  #4
+-               lda  (c64.SCRATCH_ZPWORD1),y
+		pha
+		lda  (c64.SCRATCH_ZPWORD2),y
+		sta  (c64.SCRATCH_ZPWORD1),y
+		pla
+		sta  (c64.SCRATCH_ZPWORD2),y
+		dey
+		bpl  -
+		rts
+		.pend

compiler/res/prog8lib/c64flt.p8

@@ -10,8 +10,8 @@
 c64flt {
 	; ---- this block contains C-64 floating point related functions ----
 
-		const  float  PI	= 3.141592653589793
-		const  float  TWOPI	= 6.283185307179586
+        const  float  PI        = 3.141592653589793
+        const  float  TWOPI	    = 6.283185307179586
 
 
 ; ---- C64 basic and kernal ROM float constants and functions ----
@@ -34,32 +34,33 @@ c64flt {
 		&float  FL_PIHALF	= $e2e0  ; PI / 2
 		&float  FL_TWOPI	= $e2e5  ; 2 * PI
 		&float  FL_FR4		= $e2ea  ; .25
-		 float  FL_ZERO		= 0.0    ; oddly enough 0.0 isn't available in the kernel
+		; oddly enough, 0.0 isn't available in the kernel.
+        float   FL_ZERO     = 0.0    ; oddly enough 0.0 isn't available in the kernel
 
 
 ; note: fac1/2 might get clobbered even if not mentioned in the function's name.
 ; note: for subtraction and division, the left operand is in fac2, the right operand in fac1.
 
 ; checked functions below:
-asmsub	MOVFM		(uword mflpt @ AY) clobbers(A,Y)	= $bba2		; load mflpt value from memory  in A/Y into fac1
-asmsub	FREADMEM	() clobbers(A,Y)			= $bba6		; load mflpt value from memory  in $22/$23 into fac1
-asmsub	CONUPK		(uword mflpt @ AY) clobbers(A,Y)	= $ba8c		; load mflpt value from memory  in A/Y into fac2
-asmsub	FAREADMEM	() clobbers(A,Y)			= $ba90		; load mflpt value from memory  in $22/$23 into fac2
-asmsub	MOVFA		() clobbers(A,X)			= $bbfc		; copy fac2 to fac1
-asmsub	MOVAF		() clobbers(A,X)			= $bc0c		; copy fac1 to fac2  (rounded)
-asmsub	MOVEF		() clobbers(A,X)			= $bc0f		; copy fac1 to fac2
-asmsub	MOVMF		(uword mflpt @ XY) clobbers(A,Y)	= $bbd4		; store fac1 to memory  X/Y as 5-byte mflpt
+romsub $bba2 = MOVFM(uword mflpt @ AY) clobbers(A,Y)        ; load mflpt value from memory  in A/Y into fac1
+romsub $bba6 = FREADMEM() clobbers(A,Y)                     ; load mflpt value from memory  in $22/$23 into fac1
+romsub $ba8c = CONUPK(uword mflpt @ AY) clobbers(A,Y)       ; load mflpt value from memory  in A/Y into fac2
+romsub $ba90 = FAREADMEM() clobbers(A,Y)                    ; load mflpt value from memory  in $22/$23 into fac2
+romsub $bbfc = MOVFA() clobbers(A,X)                        ; copy fac2 to fac1
+romsub $bc0c = MOVAF() clobbers(A,X)                        ; copy fac1 to fac2  (rounded)
+romsub $bc0f = MOVEF() clobbers(A,X)                        ; copy fac1 to fac2
+romsub $bbd4 = MOVMF(uword mflpt @ XY) clobbers(A,Y)        ; store fac1 to memory  X/Y as 5-byte mflpt
 
 ; fac1-> signed word in Y/A (might throw ILLEGAL QUANTITY)
 ; (tip: use c64flt.FTOSWRDAY to get A/Y output; lo/hi switched to normal little endian order)
-asmsub	FTOSWORDYA	() clobbers(X) -> ubyte @ Y, ubyte @ A  = $b1aa     ; note: calls AYINT.
+romsub $b1aa = FTOSWORDYA() clobbers(X) -> ubyte @ Y, ubyte @ A       ; note: calls AYINT.
 
 ; fac1 -> unsigned word in Y/A (might throw ILLEGAL QUANTITY) (result also in $14/15)
 ; (tip: use c64flt.GETADRAY to get A/Y output; lo/hi switched to normal little endian order)
-asmsub	GETADR		() clobbers(X) -> ubyte @ Y, ubyte @ A  = $b7f7
+romsub $b7f7 = GETADR() clobbers(X) -> ubyte @ Y, ubyte @ A
 
-asmsub	QINT		() clobbers(A,X,Y)			= $bc9b		; fac1 -> 4-byte signed integer in 98-101 ($62-$65), with the MSB FIRST.
-asmsub	AYINT		() clobbers(A,X,Y)			= $b1bf		; fac1-> signed word in 100-101 ($64-$65) MSB FIRST. (might throw ILLEGAL QUANTITY)
+romsub $bc9b = QINT() clobbers(A,X,Y)           ; fac1 -> 4-byte signed integer in 98-101 ($62-$65), with the MSB FIRST.
+romsub $b1bf = AYINT() clobbers(A,X,Y)          ; fac1-> signed word in 100-101 ($64-$65) MSB FIRST. (might throw ILLEGAL QUANTITY)
 
 ; GIVAYF: signed word in Y/A (note different lsb/msb order) -> float in fac1
 ; (tip: use c64flt.GIVAYFAY to use A/Y input; lo/hi switched to normal order)
@@ -67,50 +68,49 @@ asmsub	AYINT		() clobbers(A,X,Y)			= $b1bf		; fac1-> signed word in 100-101 ($64
 ; there is also c64flt.FREADS32  that reads from 98-101 ($62-$65) MSB FIRST
 ; there is also c64flt.FREADUS32  that reads from 98-101 ($62-$65) MSB FIRST
 ; there is also c64flt.FREADS24AXY  that reads signed int24 into fac1 from A/X/Y (lo/mid/hi bytes)
-asmsub	GIVAYF		(ubyte lo @ Y, ubyte hi @ A) clobbers(A,X,Y)	= $b391
+romsub $b391 = GIVAYF(ubyte lo @ Y, ubyte hi @ A) clobbers(A,X,Y)
 
-asmsub	FREADUY		(ubyte value @ Y) clobbers(A,X,Y)	= $b3a2		; 8 bit unsigned Y -> float in fac1
-asmsub	FREADSA		(byte value @ A) clobbers(A,X,Y)	= $bc3c		; 8 bit signed A -> float in fac1
-asmsub	FREADSTR	(ubyte length @ A) clobbers(A,X,Y)	= $b7b5		; str -> fac1, $22/23 must point to string, A=string length
-asmsub	FPRINTLN	() clobbers(A,X,Y)			= $aabc		; print string of fac1, on one line (= with newline) destroys fac1.  (consider FOUT + STROUT as well)
-asmsub	FOUT		() clobbers(X) -> uword @ AY		= $bddd		; fac1 -> string, address returned in AY ($0100)
+romsub $b3a2 = FREADUY(ubyte value @ Y) clobbers(A,X,Y)     ; 8 bit unsigned Y -> float in fac1
+romsub $bc3c = FREADSA(byte value @ A) clobbers(A,X,Y)      ; 8 bit signed A -> float in fac1
+romsub $b7b5 = FREADSTR(ubyte length @ A) clobbers(A,X,Y)   ; str -> fac1, $22/23 must point to string, A=string length
+romsub $aabc = FPRINTLN() clobbers(A,X,Y)                   ; print string of fac1, on one line (= with newline) destroys fac1.  (consider FOUT + STROUT as well)
+romsub $bddd = FOUT() clobbers(X) -> uword @ AY             ; fac1 -> string, address returned in AY ($0100)
 
-asmsub	FADDH		() clobbers(A,X,Y)			= $b849		; fac1 += 0.5, for rounding- call this before INT
-asmsub	MUL10		() clobbers(A,X,Y)			= $bae2		; fac1 *= 10
-asmsub	DIV10		() clobbers(A,X,Y)			= $bafe		; fac1 /= 10 , CAUTION: result is always positive!
-asmsub	FCOMP		(uword mflpt @ AY) clobbers(X,Y) -> ubyte @ A = $bc5b		; A = compare fac1 to mflpt in A/Y, 0=equal 1=fac1 is greater, 255=fac1 is less than
+romsub $b849 = FADDH() clobbers(A,X,Y)                      ; fac1 += 0.5, for rounding- call this before INT
+romsub $bae2 = MUL10() clobbers(A,X,Y)                      ; fac1 *= 10
+romsub $bafe = DIV10() clobbers(A,X,Y)                      ; fac1 /= 10 , CAUTION: result is always positive!
+romsub $bc5b = FCOMP(uword mflpt @ AY) clobbers(X,Y) -> ubyte @ A   ; A = compare fac1 to mflpt in A/Y, 0=equal 1=fac1 is greater, 255=fac1 is less than
 
-asmsub	FADDT		() clobbers(A,X,Y)			= $b86a		; fac1 += fac2
-asmsub	FADD		(uword mflpt @ AY) clobbers(A,X,Y)	= $b867		; fac1 += mflpt value from A/Y
-asmsub	FSUBT		() clobbers(A,X,Y)			= $b853		; fac1 = fac2-fac1   mind the order of the operands
-asmsub	FSUB		(uword mflpt @ AY) clobbers(A,X,Y)	= $b850		; fac1 = mflpt from A/Y - fac1
-asmsub	FMULTT 		() clobbers(A,X,Y)			= $ba2b		; fac1 *= fac2
-asmsub	FMULT		(uword mflpt @ AY) clobbers(A,X,Y)	= $ba28		; fac1 *= mflpt value from A/Y
-asmsub	FDIVT 		() clobbers(A,X,Y)			= $bb12		; fac1 = fac2/fac1  (remainder in fac2)  mind the order of the operands
-asmsub	FDIV  		(uword mflpt @ AY) clobbers(A,X,Y)	= $bb0f		; fac1 = mflpt in A/Y / fac1  (remainder in fac2)
-asmsub	FPWRT		() clobbers(A,X,Y)			= $bf7b		; fac1 = fac2 ** fac1
-asmsub	FPWR		(uword mflpt @ AY) clobbers(A,X,Y)	= $bf78		; fac1 = fac2 ** mflpt from A/Y
+romsub $b86a = FADDT() clobbers(A,X,Y)                      ; fac1 += fac2
+romsub $b867 = FADD(uword mflpt @ AY) clobbers(A,X,Y)       ; fac1 += mflpt value from A/Y
+romsub $b853 = FSUBT() clobbers(A,X,Y)                      ; fac1 = fac2-fac1   mind the order of the operands
+romsub $b850 = FSUB(uword mflpt @ AY) clobbers(A,X,Y)       ; fac1 = mflpt from A/Y - fac1
+romsub $ba2b = FMULTT() clobbers(A,X,Y)                     ; fac1 *= fac2
+romsub $ba28 = FMULT(uword mflpt @ AY) clobbers(A,X,Y)      ; fac1 *= mflpt value from A/Y
+romsub $bb12 = FDIVT() clobbers(A,X,Y)                      ; fac1 = fac2/fac1  (remainder in fac2)  mind the order of the operands
+romsub $bb0f = FDIV(uword mflpt @ AY) clobbers(A,X,Y)       ; fac1 = mflpt in A/Y / fac1  (remainder in fac2)
+romsub $bf7b = FPWRT() clobbers(A,X,Y)                      ; fac1 = fac2 ** fac1
+romsub $bf78 = FPWR(uword mflpt @ AY) clobbers(A,X,Y)       ; fac1 = fac2 ** mflpt from A/Y
 
-asmsub	NOTOP		() clobbers(A,X,Y)			= $aed4		; fac1 = NOT(fac1)
-asmsub	INT		() clobbers(A,X,Y)			= $bccc		; INT() truncates, use FADDH first to round instead of trunc
-asmsub	LOG		() clobbers(A,X,Y)			= $b9ea		; fac1 = LN(fac1)  (natural log)
-asmsub	SGN		() clobbers(A,X,Y)			= $bc39		; fac1 = SGN(fac1), result of SIGN (-1, 0 or 1)
-asmsub	SIGN		() -> ubyte @ A				= $bc2b		; SIGN(fac1) to A, $ff, $0, $1 for negative, zero, positive
-asmsub	ABS		()					= $bc58		; fac1 = ABS(fac1)
-asmsub	SQR		() clobbers(A,X,Y)			= $bf71		; fac1 = SQRT(fac1)
-asmsub	SQRA		() clobbers(A,X,Y)			= $bf74		; fac1 = SQRT(fac2)
-asmsub	EXP		() clobbers(A,X,Y)			= $bfed		; fac1 = EXP(fac1)  (e ** fac1)
-asmsub	NEGOP		() clobbers(A)				= $bfb4		; switch the sign of fac1
-asmsub	RND		() clobbers(A,X,Y)			= $e097		; fac1 = RND(fac1) float random number generator
-asmsub	COS		() clobbers(A,X,Y)			= $e264		; fac1 = COS(fac1)
-asmsub	SIN		() clobbers(A,X,Y)			= $e26b		; fac1 = SIN(fac1)
-asmsub	TAN		() clobbers(A,X,Y)			= $e2b4		; fac1 = TAN(fac1)
-asmsub	ATN		() clobbers(A,X,Y)			= $e30e		; fac1 = ATN(fac1)
+romsub $aed4 = NOTOP() clobbers(A,X,Y)                      ; fac1 = NOT(fac1)
+romsub $bccc = INT() clobbers(A,X,Y)                        ; INT() truncates, use FADDH first to round instead of trunc
+romsub $b9ea = LOG() clobbers(A,X,Y)                        ; fac1 = LN(fac1)  (natural log)
+romsub $bc39 = SGN() clobbers(A,X,Y)                        ; fac1 = SGN(fac1), result of SIGN (-1, 0 or 1)
+romsub $bc2b = SIGN() -> ubyte @ A                          ; SIGN(fac1) to A, $ff, $0, $1 for negative, zero, positive
+romsub $bc58 = ABS()                                        ; fac1 = ABS(fac1)
+romsub $bf71 = SQR() clobbers(A,X,Y)                        ; fac1 = SQRT(fac1)
+romsub $bf74 = SQRA() clobbers(A,X,Y)                       ; fac1 = SQRT(fac2)
+romsub $bfed = EXP() clobbers(A,X,Y)                        ; fac1 = EXP(fac1)  (e ** fac1)
+romsub $bfb4 = NEGOP() clobbers(A)                          ; switch the sign of fac1
+romsub $e097 = RND() clobbers(A,X,Y)                        ; fac1 = RND(fac1) float random number generator
+romsub $e264 = COS() clobbers(A,X,Y)                        ; fac1 = COS(fac1)
+romsub $e26b = SIN() clobbers(A,X,Y)                        ; fac1 = SIN(fac1)
+romsub $e2b4 = TAN() clobbers(A,X,Y)                        ; fac1 = TAN(fac1)
+romsub $e30e = ATN() clobbers(A,X,Y)                        ; fac1 = ATN(fac1)
 
 
 
-
-asmsub  FREADS32  () clobbers(A,X,Y)  {
+asmsub  FREADS32() clobbers(A,X,Y)  {
 	; ---- fac1 = signed int32 from $62-$65 big endian (MSB FIRST)
 	%asm {{
 		lda  $62
@@ -210,8 +210,8 @@ sub  print_fln  (float value) {
 	; ---- prints the floating point value (with a newline at the end) using basic rom routines
 	%asm {{
 		stx  c64.SCRATCH_ZPREGX
-		lda  #<print_fln_value
-		ldy  #>print_fln_value
+		lda  #<value
+		ldy  #>value
 		jsr  MOVFM		; load float into fac1
 		jsr  FPRINTLN		; print fac1 with newline
 		ldx  c64.SCRATCH_ZPREGX
@@ -220,740 +220,6 @@ sub  print_fln  (float value) {
 
 }
 
-
-; --- low level floating point assembly routines
-%asm {{
-ub2float	.proc
-		; -- convert ubyte in SCRATCH_ZPB1 to float at address A/Y
-		;    clobbers A, Y
-		stx  c64.SCRATCH_ZPREGX
-		sta  c64.SCRATCH_ZPWORD2
-		sty  c64.SCRATCH_ZPWORD2+1
-		ldy  c64.SCRATCH_ZPB1
-		jsr  FREADUY
-_fac_to_mem	ldx  c64.SCRATCH_ZPWORD2
-		ldy  c64.SCRATCH_ZPWORD2+1
-		jsr  MOVMF
-		ldx  c64.SCRATCH_ZPREGX
-		rts
-		.pend
-
-b2float		.proc
-		; -- convert byte in SCRATCH_ZPB1 to float at address A/Y
-		;    clobbers A, Y
-		stx  c64.SCRATCH_ZPREGX
-		sta  c64.SCRATCH_ZPWORD2
-		sty  c64.SCRATCH_ZPWORD2+1
-		lda  c64.SCRATCH_ZPB1
-		jsr  FREADSA
-		jmp  ub2float._fac_to_mem
-		.pend
-
-uw2float	.proc
-		; -- convert uword in SCRATCH_ZPWORD1 to float at address A/Y
-		stx  c64.SCRATCH_ZPREGX
-		sta  c64.SCRATCH_ZPWORD2
-		sty  c64.SCRATCH_ZPWORD2+1
-		lda  c64.SCRATCH_ZPWORD1
-		ldy  c64.SCRATCH_ZPWORD1+1
-		jsr  GIVUAYFAY
-		jmp  ub2float._fac_to_mem
-		.pend
-
-w2float		.proc
-		; -- convert word in SCRATCH_ZPWORD1 to float at address A/Y
-		stx  c64.SCRATCH_ZPREGX
-		sta  c64.SCRATCH_ZPWORD2
-		sty  c64.SCRATCH_ZPWORD2+1
-		ldy  c64.SCRATCH_ZPWORD1
-		lda  c64.SCRATCH_ZPWORD1+1
-		jsr  GIVAYF
-		jmp  ub2float._fac_to_mem
-		.pend
-
-stack_b2float	.proc
-		; -- b2float operating on the stack
-		inx
-		lda  c64.ESTACK_LO,x
-		stx  c64.SCRATCH_ZPREGX
-		jsr  FREADSA
-		jmp  push_fac1_as_result
-		.pend
-
-stack_w2float	.proc
-		; -- w2float operating on the stack
-		inx
-		ldy  c64.ESTACK_LO,x
-		lda  c64.ESTACK_HI,x
-		stx  c64.SCRATCH_ZPREGX
-		jsr  GIVAYF
-		jmp  push_fac1_as_result
-		.pend
-
-stack_ub2float	.proc
-		; -- ub2float operating on the stack
-		inx
-		lda  c64.ESTACK_LO,x
-		stx  c64.SCRATCH_ZPREGX
-		tay
-		jsr  FREADUY
-		jmp  push_fac1_as_result
-		.pend
-
-stack_uw2float	.proc
-		; -- uw2float operating on the stack
-		inx
-		lda  c64.ESTACK_LO,x
-		ldy  c64.ESTACK_HI,x
-		stx  c64.SCRATCH_ZPREGX
-		jsr  GIVUAYFAY
-		jmp  push_fac1_as_result
-		.pend
-
-stack_float2w	.proc               ; also used for float2b
-		jsr  pop_float_fac1
-		stx  c64.SCRATCH_ZPREGX
-		jsr  AYINT
-		ldx  c64.SCRATCH_ZPREGX
-		lda  $64
-		sta  c64.ESTACK_HI,x
-		lda  $65
-		sta  c64.ESTACK_LO,x
-		dex
-		rts
-		.pend
-
-stack_float2uw	.proc               ; also used for float2ub
-		jsr  pop_float_fac1
-		stx  c64.SCRATCH_ZPREGX
-		jsr  GETADR
-		ldx  c64.SCRATCH_ZPREGX
-		sta  c64.ESTACK_HI,x
-		tya
-		sta  c64.ESTACK_LO,x
-		dex
-		rts
-		.pend
-
-push_float	.proc
-		; ---- push mflpt5 in A/Y onto stack
-		; (taking 3 stack positions = 6 bytes of which 1 is padding)
-		sta  c64.SCRATCH_ZPWORD1
-		sty  c64.SCRATCH_ZPWORD1+1
-		ldy  #0
-		lda  (c64.SCRATCH_ZPWORD1),y
-		sta  c64.ESTACK_LO,x
-		iny
-		lda  (c64.SCRATCH_ZPWORD1),y
-		sta  c64.ESTACK_HI,x
-		dex
-		iny
-		lda  (c64.SCRATCH_ZPWORD1),y
-		sta  c64.ESTACK_LO,x
-		iny
-		lda  (c64.SCRATCH_ZPWORD1),y
-		sta  c64.ESTACK_HI,x
-		dex
-		iny
-		lda  (c64.SCRATCH_ZPWORD1),y
-		sta  c64.ESTACK_LO,x
-		dex
-		rts
-		.pend
-
-func_rndf	.proc
-		; -- put a random floating point value on the stack
-		stx  c64.SCRATCH_ZPREG
-		lda  #1
-		jsr  FREADSA
-		jsr  RND		; rng into fac1
-		ldx  #<_rndf_rnum5
-		ldy  #>_rndf_rnum5
-		jsr  MOVMF	; fac1 to mem X/Y
-		ldx  c64.SCRATCH_ZPREG
-		lda  #<_rndf_rnum5
-		ldy  #>_rndf_rnum5
-		jmp  push_float
-_rndf_rnum5	.byte  0,0,0,0,0
-		.pend
-
-push_float_from_indexed_var	.proc
-		; -- push the float from the array at A/Y with index on stack, onto the stack.
-		sta  c64.SCRATCH_ZPWORD1
-		sty  c64.SCRATCH_ZPWORD1+1
-		jsr  prog8_lib.pop_index_times_5
-		jsr  prog8_lib.add_a_to_zpword
-		lda  c64.SCRATCH_ZPWORD1
-		ldy  c64.SCRATCH_ZPWORD1+1
-		jmp  push_float
-		.pend
-
-pop_float	.proc
-		; ---- pops mflpt5 from stack to memory A/Y
-		; (frees 3 stack positions = 6 bytes of which 1 is padding)
-		sta  c64.SCRATCH_ZPWORD1
-		sty  c64.SCRATCH_ZPWORD1+1
-		ldy  #4
-		inx
-		lda  c64.ESTACK_LO,x
-		sta  (c64.SCRATCH_ZPWORD1),y
-		dey
-		inx
-		lda  c64.ESTACK_HI,x
-		sta  (c64.SCRATCH_ZPWORD1),y
-		dey
-		lda  c64.ESTACK_LO,x
-		sta  (c64.SCRATCH_ZPWORD1),y
-		dey
-		inx
-		lda  c64.ESTACK_HI,x
-		sta  (c64.SCRATCH_ZPWORD1),y
-		dey
-		lda  c64.ESTACK_LO,x
-		sta  (c64.SCRATCH_ZPWORD1),y
-		rts
-		.pend
-
-pop_float_fac1	.proc
-		; -- pops float from stack into FAC1
-		lda  #<fmath_float1
-		ldy  #>fmath_float1
-		jsr  pop_float
-		lda  #<fmath_float1
-		ldy  #>fmath_float1
-		jmp  MOVFM
-		.pend
-
-pop_float_to_indexed_var	.proc
-		; -- pop the float on the stack, to the memory in the array at A/Y indexed by the byte on stack
-		sta  c64.SCRATCH_ZPWORD1
-		sty  c64.SCRATCH_ZPWORD1+1
-		jsr  prog8_lib.pop_index_times_5
-		jsr  prog8_lib.add_a_to_zpword
-		lda  c64.SCRATCH_ZPWORD1
-		ldy  c64.SCRATCH_ZPWORD1+1
-		jmp  pop_float
-		.pend
-
-copy_float	.proc
-		; -- copies the 5 bytes of the mflt value pointed to by SCRATCH_ZPWORD1,
-		;    into the 5 bytes pointed to by A/Y.  Clobbers A,Y.
-		sta  c64.SCRATCH_ZPWORD2
-		sty  c64.SCRATCH_ZPWORD2+1
-		ldy  #0
-		lda  (c64.SCRATCH_ZPWORD1),y
-		sta  (c64.SCRATCH_ZPWORD2),y
-		iny
-		lda  (c64.SCRATCH_ZPWORD1),y
-		sta  (c64.SCRATCH_ZPWORD2),y
-		iny
-		lda  (c64.SCRATCH_ZPWORD1),y
-		sta  (c64.SCRATCH_ZPWORD2),y
-		iny
-		lda  (c64.SCRATCH_ZPWORD1),y
-		sta  (c64.SCRATCH_ZPWORD2),y
-		iny
-		lda  (c64.SCRATCH_ZPWORD1),y
-		sta  (c64.SCRATCH_ZPWORD2),y
-		rts
-		.pend
-
-inc_var_f	.proc
-		; -- add 1 to float pointed to by A/Y
-		sta  c64.SCRATCH_ZPWORD1
-		sty  c64.SCRATCH_ZPWORD1+1
-		stx  c64.SCRATCH_ZPREGX
-		jsr  MOVFM
-		lda  #<FL_FONE
-		ldy  #>FL_FONE
-		jsr  FADD
-		ldx  c64.SCRATCH_ZPWORD1
-		ldy  c64.SCRATCH_ZPWORD1+1
-		jsr  MOVMF
-		ldx  c64.SCRATCH_ZPREGX
-		rts
-		.pend
-
-dec_var_f	.proc
-		; -- subtract 1 from float pointed to by A/Y
-		sta  c64.SCRATCH_ZPWORD1
-		sty  c64.SCRATCH_ZPWORD1+1
-		stx  c64.SCRATCH_ZPREGX
-		lda  #<FL_FONE
-		ldy  #>FL_FONE
-		jsr  MOVFM
-		lda  c64.SCRATCH_ZPWORD1
-		ldy  c64.SCRATCH_ZPWORD1+1
-		jsr  FSUB
-		ldx  c64.SCRATCH_ZPWORD1
-		ldy  c64.SCRATCH_ZPWORD1+1
-		jsr  MOVMF
-		ldx  c64.SCRATCH_ZPREGX
-		rts
-		.pend
-
-inc_indexed_var_f	.proc
-		; -- add 1 to float in array pointed to by A/Y, at index X
-		pha
-		txa
-		sta  c64.SCRATCH_ZPB1
-		asl  a
-		asl  a
-		clc
-		adc  c64.SCRATCH_ZPB1
-		sta  c64.SCRATCH_ZPB1
-		pla
-		clc
-		adc  c64.SCRATCH_ZPB1
-		bcc  +
-		iny
-+		jmp  inc_var_f
-		.pend
-
-dec_indexed_var_f	.proc
-		; -- subtract 1 to float in array pointed to by A/Y, at index X
-		pha
-		txa
-		sta  c64.SCRATCH_ZPB1
-		asl  a
-		asl  a
-		clc
-		adc  c64.SCRATCH_ZPB1
-		sta  c64.SCRATCH_ZPB1
-		pla
-		clc
-		adc  c64.SCRATCH_ZPB1
-		bcc  +
-		iny
-+		jmp  dec_var_f
-		.pend
-
-
-pop_2_floats_f2_in_fac1	.proc
-		; -- pop 2 floats from stack, load the second one in FAC1 as well
-		lda  #<fmath_float2
-		ldy  #>fmath_float2
-		jsr  pop_float
-		lda  #<fmath_float1
-		ldy  #>fmath_float1
-		jsr  pop_float
-		lda  #<fmath_float2
-		ldy  #>fmath_float2
-		jmp  MOVFM
-		.pend
-
-
-fmath_float1	.byte 0,0,0,0,0	; storage for a mflpt5 value
-fmath_float2	.byte 0,0,0,0,0	; storage for a mflpt5 value
-
-push_fac1_as_result	.proc
-		; -- push the float in FAC1 onto the stack, and return from calculation
-		ldx  #<fmath_float1
-		ldy  #>fmath_float1
-		jsr  MOVMF
-		lda  #<fmath_float1
-		ldy  #>fmath_float1
-		ldx  c64.SCRATCH_ZPREGX
-		jmp  push_float
-		.pend
-
-pow_f		.proc
-		; -- push f1 ** f2 on stack
-		lda  #<fmath_float2
-		ldy  #>fmath_float2
-		jsr  pop_float
-		lda  #<fmath_float1
-		ldy  #>fmath_float1
-		jsr  pop_float
-		stx  c64.SCRATCH_ZPREGX
-		lda  #<fmath_float1
-		ldy  #>fmath_float1
-		jsr  CONUPK		; fac2 = float1
-		lda  #<fmath_float2
-		ldy  #>fmath_float2
-		jsr  FPWR
-		ldx  c64.SCRATCH_ZPREGX
-		jmp  push_fac1_as_result
-		.pend
-
-div_f		.proc
-		; -- push f1/f2 on stack
-		jsr  pop_2_floats_f2_in_fac1
-		stx  c64.SCRATCH_ZPREGX
-		lda  #<fmath_float1
-		ldy  #>fmath_float1
-		jsr  FDIV
-		jmp  push_fac1_as_result
-		.pend
-
-add_f		.proc
-		; -- push f1+f2 on stack
-		jsr  pop_2_floats_f2_in_fac1
-		stx  c64.SCRATCH_ZPREGX
-		lda  #<fmath_float1
-		ldy  #>fmath_float1
-		jsr  FADD
-		jmp  push_fac1_as_result
-		.pend
-
-sub_f		.proc
-		; -- push f1-f2 on stack
-		jsr  pop_2_floats_f2_in_fac1
-		stx  c64.SCRATCH_ZPREGX
-		lda  #<fmath_float1
-		ldy  #>fmath_float1
-		jsr  FSUB
-		jmp  push_fac1_as_result
-		.pend
-
-mul_f		.proc
-		; -- push f1*f2 on stack
-		jsr  pop_2_floats_f2_in_fac1
-		stx  c64.SCRATCH_ZPREGX
-		lda  #<fmath_float1
-		ldy  #>fmath_float1
-		jsr  FMULT
-		jmp  push_fac1_as_result
-		.pend
-
-neg_f		.proc
-		; -- push -flt back on stack
-		jsr  pop_float_fac1
-		stx  c64.SCRATCH_ZPREGX
-		jsr  NEGOP
-		jmp  push_fac1_as_result
-		.pend
-
-abs_f		.proc
-		; -- push abs(float) on stack (as float)
-		jsr  pop_float_fac1
-		stx  c64.SCRATCH_ZPREGX
-		jsr  ABS
-		jmp  push_fac1_as_result
-		.pend
-
-equal_f		.proc
-		; -- are the two mflpt5 numbers on the stack identical?
-		inx
-		inx
-		inx
-		inx
-		lda  c64.ESTACK_LO-3,x
-		cmp  c64.ESTACK_LO,x
-		bne  _equals_false
-		lda  c64.ESTACK_LO-2,x
-		cmp  c64.ESTACK_LO+1,x
-		bne  _equals_false
-		lda  c64.ESTACK_LO-1,x
-		cmp  c64.ESTACK_LO+2,x
-		bne  _equals_false
-		lda  c64.ESTACK_HI-2,x
-		cmp  c64.ESTACK_HI+1,x
-		bne  _equals_false
-		lda  c64.ESTACK_HI-1,x
-		cmp  c64.ESTACK_HI+2,x
-		bne  _equals_false
-_equals_true	lda  #1
-_equals_store	inx
-		sta  c64.ESTACK_LO+1,x
-		rts
-_equals_false	lda  #0
-		beq  _equals_store
-		.pend
-
-notequal_f	.proc
-		; -- are the two mflpt5 numbers on the stack different?
-		jsr  equal_f
-		eor  #1		; invert the result
-		sta  c64.ESTACK_LO+1,x
-		rts
-		.pend
-
-less_f		.proc
-		; -- is f1 < f2?
-		jsr  compare_floats
-		cmp  #255
-		beq  compare_floats._return_true
-		bne  compare_floats._return_false
-		.pend
-
-
-lesseq_f	.proc
-		; -- is f1 <= f2?
-		jsr  compare_floats
-		cmp  #255
-		beq  compare_floats._return_true
-		cmp  #0
-		beq  compare_floats._return_true
-		bne  compare_floats._return_false
-		.pend
-
-greater_f	.proc
-		; -- is f1 > f2?
-		jsr  compare_floats
-		cmp  #1
-		beq  compare_floats._return_true
-		bne  compare_floats._return_false
-		.pend
-
-greatereq_f	.proc
-		; -- is f1 >= f2?
-		jsr  compare_floats
-		cmp  #1
-		beq  compare_floats._return_true
-		cmp  #0
-		beq  compare_floats._return_true
-		bne  compare_floats._return_false
-		.pend
-
-compare_floats	.proc
-		lda  #<fmath_float2
-		ldy  #>fmath_float2
-		jsr  pop_float
-		lda  #<fmath_float1
-		ldy  #>fmath_float1
-		jsr  pop_float
-		lda  #<fmath_float1
-		ldy  #>fmath_float1
-		jsr  MOVFM		; fac1 = flt1
-		lda  #<fmath_float2
-		ldy  #>fmath_float2
-		stx  c64.SCRATCH_ZPREG
-		jsr  FCOMP		; A = flt1 compared with flt2 (0=equal, 1=flt1>flt2, 255=flt1<flt2)
-		ldx  c64.SCRATCH_ZPREG
-		rts
-_return_false	lda  #0
-_return_result  sta  c64.ESTACK_LO,x
-		dex
-		rts
-_return_true	lda  #1
-		bne  _return_result
-		.pend
-
-func_sin	.proc
-		; -- push sin(f) back onto stack
-		jsr  pop_float_fac1
-		stx  c64.SCRATCH_ZPREGX
-		jsr  SIN
-		jmp  push_fac1_as_result
-		.pend
-
-func_cos	.proc
-		; -- push cos(f) back onto stack
-		jsr  pop_float_fac1
-		stx  c64.SCRATCH_ZPREGX
-		jsr  COS
-		jmp  push_fac1_as_result
-		.pend
-
-func_tan	.proc
-		; -- push tan(f) back onto stack
-		jsr  pop_float_fac1
-		stx  c64.SCRATCH_ZPREGX
-		jsr  TAN
-		jmp  push_fac1_as_result
-		.pend
-
-func_atan	.proc
-		; -- push atan(f) back onto stack
-		jsr  pop_float_fac1
-		stx  c64.SCRATCH_ZPREGX
-		jsr  ATN
-		jmp  push_fac1_as_result
-		.pend
-
-func_ln		.proc
-		; -- push ln(f) back onto stack
-		jsr  pop_float_fac1
-		stx  c64.SCRATCH_ZPREGX
-		jsr  LOG
-		jmp  push_fac1_as_result
-		.pend
-
-func_log2	.proc
-		; -- push log base 2, ln(f)/ln(2), back onto stack
-		jsr  pop_float_fac1
-		stx  c64.SCRATCH_ZPREGX
-		jsr  LOG
-		jsr  MOVEF
-		lda  #<c64.FL_LOG2
-		ldy  #>c64.FL_LOG2
-		jsr  MOVFM
-		jsr  FDIVT
-		jmp  push_fac1_as_result
-		.pend
-
-func_sqrt	.proc
-		jsr  pop_float_fac1
-		stx  c64.SCRATCH_ZPREGX
-		jsr  SQR
-		jmp  push_fac1_as_result
-		.pend
-
-func_rad	.proc
-		; -- convert degrees to radians (d * pi / 180)
-		jsr  pop_float_fac1
-		stx  c64.SCRATCH_ZPREGX
-		lda  #<_pi_div_180
-		ldy  #>_pi_div_180
-		jsr  FMULT
-		jmp  push_fac1_as_result
-_pi_div_180	.byte 123, 14, 250, 53, 18		; pi / 180
-		.pend
-
-func_deg	.proc
-		; -- convert radians to degrees (d * (1/ pi * 180))
-		jsr  pop_float_fac1
-		stx  c64.SCRATCH_ZPREGX
-		lda  #<_one_over_pi_div_180
-		ldy  #>_one_over_pi_div_180
-		jsr  FMULT
-		jmp  push_fac1_as_result
-_one_over_pi_div_180	.byte 134, 101, 46, 224, 211		; 1 / (pi * 180)
-		.pend
-
-func_round	.proc
-		jsr  pop_float_fac1
-		stx  c64.SCRATCH_ZPREGX
-		jsr  FADDH
-		jsr  INT
-		jmp  push_fac1_as_result
-		.pend
-
-func_floor	.proc
-		jsr  pop_float_fac1
-		stx  c64.SCRATCH_ZPREGX
-		jsr  INT
-		jmp  push_fac1_as_result
-		.pend
-
-func_ceil	.proc
-		; -- ceil: tr = int(f); if tr==f -> return  else return tr+1
-		jsr  pop_float_fac1
-		stx  c64.SCRATCH_ZPREGX
-		ldx  #<fmath_float1
-		ldy  #>fmath_float1
-		jsr  MOVMF
-		jsr  INT
-		lda  #<fmath_float1
-		ldy  #>fmath_float1
-		jsr  FCOMP
-		cmp  #0
-		beq  +
-		lda  #<FL_FONE
-		ldy  #>FL_FONE
-		jsr  FADD
-+		jmp  push_fac1_as_result
-		.pend
-
-func_any_f	.proc
-		inx
-		lda  c64.ESTACK_LO,x	; array size
-		sta  c64.SCRATCH_ZPB1
-		asl  a
-		asl  a
-		clc
-		adc  c64.SCRATCH_ZPB1	; times 5 because of float
-		jmp  prog8_lib.func_any_b._entry
-		.pend
-
-func_all_f	.proc
-		inx
-		jsr  prog8_lib.peek_address
-		lda  c64.ESTACK_LO,x	; array size
-		sta  c64.SCRATCH_ZPB1
-		asl  a
-		asl  a
-		clc
-		adc  c64.SCRATCH_ZPB1	; times 5 because of float
-		tay
-		dey
--		lda  (c64.SCRATCH_ZPWORD1),y
-		clc
-		dey
-		adc  (c64.SCRATCH_ZPWORD1),y
-		dey
-		adc  (c64.SCRATCH_ZPWORD1),y
-		dey
-		adc  (c64.SCRATCH_ZPWORD1),y
-		dey
-		adc  (c64.SCRATCH_ZPWORD1),y
-		dey
-		cmp  #0
-		beq  +
-        cpy  #255
-        bne  -
-		lda  #1
-		sta  c64.ESTACK_LO+1,x
-		rts
-+		sta  c64.ESTACK_LO+1,x
-		rts
-		.pend
-
-func_max_f	.proc
-		lda  #255
-		sta  _minmax_cmp+1
-		lda  #<_largest_neg_float
-		ldy  #>_largest_neg_float
-_minmax_entry	jsr  MOVFM
-		jsr  prog8_lib.pop_array_and_lengthmin1Y
-		stx  c64.SCRATCH_ZPREGX
--		sty  c64.SCRATCH_ZPREG
-		lda  c64.SCRATCH_ZPWORD1
-		ldy  c64.SCRATCH_ZPWORD1+1
-		jsr  FCOMP
-_minmax_cmp	cmp  #255			; modified
-		bne  +
-		lda  c64.SCRATCH_ZPWORD1
-		ldy  c64.SCRATCH_ZPWORD1+1
-		jsr  MOVFM
-+		lda  c64.SCRATCH_ZPWORD1
-		clc
-		adc  #5
-		sta  c64.SCRATCH_ZPWORD1
-		bcc  +
-		inc  c64.SCRATCH_ZPWORD1+1
-+		ldy  c64.SCRATCH_ZPREG
-		dey
-		cpy  #255
-		bne  -
-		jmp  push_fac1_as_result
-_largest_neg_float	.byte 255,255,255,255,255		; largest negative float -1.7014118345e+38
-		.pend
-
-func_min_f	.proc
-		lda  #1
-		sta  func_max_f._minmax_cmp+1
-		lda  #<_largest_pos_float
-		ldy  #>_largest_pos_float
-		jmp  func_max_f._minmax_entry
-_largest_pos_float	.byte  255,127,255,255,255		; largest positive float
-		rts
-		.pend
-
-func_sum_f	.proc
-		lda  #<FL_ZERO
-		ldy  #>FL_ZERO
-		jsr  MOVFM
-		jsr  prog8_lib.pop_array_and_lengthmin1Y
-		stx  c64.SCRATCH_ZPREGX
--		sty  c64.SCRATCH_ZPREG
-		lda  c64.SCRATCH_ZPWORD1
-		ldy  c64.SCRATCH_ZPWORD1+1
-		jsr  FADD
-		ldy  c64.SCRATCH_ZPREG
-		dey
-		cpy  #255
-		beq  +
-		lda  c64.SCRATCH_ZPWORD1
-		clc
-		adc  #5
-		sta  c64.SCRATCH_ZPWORD1
-		bcc  -
-		inc  c64.SCRATCH_ZPWORD1+1
-		bne  -
-+		jmp  push_fac1_as_result
-		.pend
-}}
+%asminclude "library:c64floats.asm", ""
 
 }  ; ------ end of block c64flt

compiler/res/prog8lib/c64lib.p8

@@ -7,178 +7,178 @@
 
 
 c64 {
-		const   uword  ESTACK_LO	= $ce00		; evaluation stack (lsb)
-		const   uword  ESTACK_HI	= $cf00		; evaluation stack (msb)
-		&ubyte  SCRATCH_ZPB1		= $02		; scratch byte 1 in ZP
-		&ubyte  SCRATCH_ZPREG		= $03		; scratch register in ZP
-		&ubyte  SCRATCH_ZPREGX		= $fa		; temp storage for X register (stack pointer)
-		&uword  SCRATCH_ZPWORD1		= $fb		; scratch word in ZP ($fb/$fc)
-		&uword  SCRATCH_ZPWORD2		= $fd		; scratch word in ZP ($fd/$fe)
+        const  uword  ESTACK_LO = $ce00     ; evaluation stack (lsb)
+        const  uword  ESTACK_HI = $cf00     ; evaluation stack (msb)
+        &ubyte  SCRATCH_ZPB1    = $02       ; scratch byte 1 in ZP
+        &ubyte  SCRATCH_ZPREG   = $03       ; scratch register in ZP
+        &ubyte  SCRATCH_ZPREGX  = $fa       ; temp storage for X register (stack pointer)
+        &uword  SCRATCH_ZPWORD1 = $fb       ; scratch word in ZP ($fb/$fc)
+        &uword  SCRATCH_ZPWORD2 = $fd       ; scratch word in ZP ($fd/$fe)
 
 
-		&ubyte  TIME_HI			= $a0		; software jiffy clock, hi byte
-		&ubyte  TIME_MID		= $a1		;  .. mid byte
-		&ubyte  TIME_LO			= $a2		;    .. lo byte. Updated by IRQ every 1/60 sec
-		&ubyte  STKEY			= $91		; various keyboard statuses (updated by IRQ)
-		&ubyte  SFDX			= $cb		; current key pressed (matrix value) (updated by IRQ)
+        &ubyte  TIME_HI         = $a0       ; software jiffy clock, hi byte
+        &ubyte  TIME_MID        = $a1       ;  .. mid byte
+        &ubyte  TIME_LO         = $a2       ;    .. lo byte. Updated by IRQ every 1/60 sec
+        &ubyte  STKEY           = $91       ; various keyboard statuses (updated by IRQ)
+        &ubyte  SFDX            = $cb       ; current key pressed (matrix value) (updated by IRQ)
 
-		&ubyte  COLOR			= $0286		; cursor color
-		&ubyte  HIBASE			= $0288		; screen base address / 256 (hi-byte of screen memory address)
-		&uword  CINV			= $0314		; IRQ vector
-		&uword  NMI_VEC			= $FFFA		; 6502 nmi vector, determined by the kernal if banked in
-		&uword  RESET_VEC		= $FFFC		; 6502 reset vector, determined by the kernal if banked in
-		&uword  IRQ_VEC			= $FFFE		; 6502 interrupt vector, determined by the kernal if banked in
+        &ubyte  COLOR           = $0286     ; cursor color
+        &ubyte  HIBASE          = $0288     ; screen base address / 256 (hi-byte of screen memory address)
+        &uword  CINV            = $0314     ; IRQ vector
+        &uword  NMI_VEC         = $FFFA     ; 6502 nmi vector, determined by the kernal if banked in
+        &uword  RESET_VEC       = $FFFC     ; 6502 reset vector, determined by the kernal if banked in
+        &uword  IRQ_VEC         = $FFFE     ; 6502 interrupt vector, determined by the kernal if banked in
 
-		; the default addresses for the character screen chars and colors
-		const   uword  Screen		= $0400		; to have this as an array[40*25] the compiler would have to support array size > 255
-		const   uword  Colors		= $d800		; to have this as an array[40*25] the compiler would have to support array size > 255
+        ; the default addresses for the character screen chars and colors
+        const  uword  Screen    = $0400     ; to have this as an array[40*25] the compiler would have to support array size > 255
+        const  uword  Colors    = $d800     ; to have this as an array[40*25] the compiler would have to support array size > 255
 
-		; the default locations of the 8 sprite pointers (store address of sprite / 64)
-		&ubyte  SPRPTR0			= 2040
-		&ubyte  SPRPTR1			= 2041
-		&ubyte  SPRPTR2			= 2042
-		&ubyte  SPRPTR3			= 2043
-		&ubyte  SPRPTR4			= 2044
-		&ubyte  SPRPTR5			= 2045
-		&ubyte  SPRPTR6			= 2046
-		&ubyte  SPRPTR7			= 2047
-		&ubyte[8]  SPRPTR		= 2040		; the 8 sprite pointers as an array.
+        ; the default locations of the 8 sprite pointers (store address of sprite / 64)
+        &ubyte  SPRPTR0         = 2040
+        &ubyte  SPRPTR1         = 2041
+        &ubyte  SPRPTR2         = 2042
+        &ubyte  SPRPTR3         = 2043
+        &ubyte  SPRPTR4         = 2044
+        &ubyte  SPRPTR5         = 2045
+        &ubyte  SPRPTR6         = 2046
+        &ubyte  SPRPTR7         = 2047
+        &ubyte[8]  SPRPTR       = 2040      ; the 8 sprite pointers as an array.
 
 
 ; ---- VIC-II 6567/6569/856x registers ----
 
-		&ubyte  SP0X		= $d000
-		&ubyte  SP0Y		= $d001
-		&ubyte  SP1X		= $d002
-		&ubyte  SP1Y		= $d003
-		&ubyte  SP2X		= $d004
-		&ubyte  SP2Y		= $d005
-		&ubyte  SP3X		= $d006
-		&ubyte  SP3Y		= $d007
-		&ubyte  SP4X		= $d008
-		&ubyte  SP4Y		= $d009
-		&ubyte  SP5X		= $d00a
-		&ubyte  SP5Y		= $d00b
-		&ubyte  SP6X		= $d00c
-		&ubyte  SP6Y		= $d00d
-		&ubyte  SP7X		= $d00e
-		&ubyte  SP7Y		= $d00f
-		&ubyte[16]  SPXY	= $d000		; the 8 sprite X and Y registers as an array.
-		&uword[8]  SPXYW	= $d000		; the 8 sprite X and Y registers as a combined xy word array.
+        &ubyte  SP0X            = $d000
+        &ubyte  SP0Y            = $d001
+        &ubyte  SP1X            = $d002
+        &ubyte  SP1Y            = $d003
+        &ubyte  SP2X            = $d004
+        &ubyte  SP2Y            = $d005
+        &ubyte  SP3X            = $d006
+        &ubyte  SP3Y            = $d007
+        &ubyte  SP4X            = $d008
+        &ubyte  SP4Y            = $d009
+        &ubyte  SP5X            = $d00a
+        &ubyte  SP5Y            = $d00b
+        &ubyte  SP6X            = $d00c
+        &ubyte  SP6Y            = $d00d
+        &ubyte  SP7X            = $d00e
+        &ubyte  SP7Y            = $d00f
+        &ubyte[16]  SPXY        = $d000        ; the 8 sprite X and Y registers as an array.
+        &uword[8]  SPXYW        = $d000        ; the 8 sprite X and Y registers as a combined xy word array.
 
-		&ubyte  MSIGX		= $d010
-		&ubyte  SCROLY		= $d011
-		&ubyte  RASTER		= $d012
-		&ubyte  LPENX		= $d013
-		&ubyte  LPENY		= $d014
-		&ubyte  SPENA		= $d015
-		&ubyte  SCROLX		= $d016
-		&ubyte  YXPAND		= $d017
-		&ubyte  VMCSB		= $d018
-		&ubyte  VICIRQ		= $d019
-		&ubyte  IREQMASK	= $d01a
-		&ubyte  SPBGPR		= $d01b
-		&ubyte  SPMC		= $d01c
-		&ubyte  XXPAND		= $d01d
-		&ubyte  SPSPCL		= $d01e
-		&ubyte  SPBGCL		= $d01f
+        &ubyte  MSIGX           = $d010
+        &ubyte  SCROLY          = $d011
+        &ubyte  RASTER          = $d012
+        &ubyte  LPENX           = $d013
+        &ubyte  LPENY           = $d014
+        &ubyte  SPENA           = $d015
+        &ubyte  SCROLX          = $d016
+        &ubyte  YXPAND          = $d017
+        &ubyte  VMCSB           = $d018
+        &ubyte  VICIRQ          = $d019
+        &ubyte  IREQMASK        = $d01a
+        &ubyte  SPBGPR          = $d01b
+        &ubyte  SPMC            = $d01c
+        &ubyte  XXPAND          = $d01d
+        &ubyte  SPSPCL          = $d01e
+        &ubyte  SPBGCL          = $d01f
 
-		&ubyte  EXTCOL		= $d020		; border color
-		&ubyte  BGCOL0		= $d021		; screen color
-		&ubyte  BGCOL1		= $d022
-		&ubyte  BGCOL2		= $d023
-		&ubyte  BGCOL4		= $d024
-		&ubyte  SPMC0		= $d025
-		&ubyte  SPMC1		= $d026
-		&ubyte  SP0COL		= $d027
-		&ubyte  SP1COL		= $d028
-		&ubyte  SP2COL		= $d029
-		&ubyte  SP3COL		= $d02a
-		&ubyte  SP4COL		= $d02b
-		&ubyte  SP5COL		= $d02c
-		&ubyte  SP6COL		= $d02d
-		&ubyte  SP7COL		= $d02e
-		&ubyte[8]  SPCOL	= $d027
+        &ubyte  EXTCOL          = $d020        ; border color
+        &ubyte  BGCOL0          = $d021        ; screen color
+        &ubyte  BGCOL1          = $d022
+        &ubyte  BGCOL2          = $d023
+        &ubyte  BGCOL4          = $d024
+        &ubyte  SPMC0           = $d025
+        &ubyte  SPMC1           = $d026
+        &ubyte  SP0COL          = $d027
+        &ubyte  SP1COL          = $d028
+        &ubyte  SP2COL          = $d029
+        &ubyte  SP3COL          = $d02a
+        &ubyte  SP4COL          = $d02b
+        &ubyte  SP5COL          = $d02c
+        &ubyte  SP6COL          = $d02d
+        &ubyte  SP7COL          = $d02e
+        &ubyte[8]  SPCOL        = $d027
 
 
 ; ---- end of VIC-II registers ----
 
 ; ---- CIA 6526 1 & 2 registers ----
 
-		&ubyte  CIA1PRA		= $DC00		; CIA 1 DRA, keyboard column drive (and joystick control port #2)
-		&ubyte  CIA1PRB		= $DC01		; CIA 1 DRB, keyboard row port (and joystick control port #1)
-		&ubyte  CIA1DDRA	= $DC02		; CIA 1 DDRA, keyboard column
-		&ubyte  CIA1DDRB	= $DC03		; CIA 1 DDRB, keyboard row
-		&ubyte  CIA1TAL		= $DC04		; CIA 1 timer A low byte
-		&ubyte  CIA1TAH		= $DC05		; CIA 1 timer A high byte
-		&ubyte  CIA1TBL		= $DC06		; CIA 1 timer B low byte
-		&ubyte  CIA1TBH		= $DC07		; CIA 1 timer B high byte
-		&ubyte  CIA1TOD10	= $DC08		; time of day, 1/10 sec.
-		&ubyte  CIA1TODSEC	= $DC09		; time of day, seconds
-		&ubyte  CIA1TODMMIN	= $DC0A		; time of day, minutes
-		&ubyte  CIA1TODHR	= $DC0B		; time of day, hours
-		&ubyte  CIA1SDR		= $DC0C		; Serial Data Register
-		&ubyte  CIA1ICR		= $DC0D
-		&ubyte  CIA1CRA		= $DC0E
-		&ubyte  CIA1CRB		= $DC0F
+        &ubyte  CIA1PRA         = $DC00        ; CIA 1 DRA, keyboard column drive (and joystick control port #2)
+        &ubyte  CIA1PRB         = $DC01        ; CIA 1 DRB, keyboard row port (and joystick control port #1)
+        &ubyte  CIA1DDRA        = $DC02        ; CIA 1 DDRA, keyboard column
+        &ubyte  CIA1DDRB        = $DC03        ; CIA 1 DDRB, keyboard row
+        &ubyte  CIA1TAL         = $DC04        ; CIA 1 timer A low byte
+        &ubyte  CIA1TAH         = $DC05        ; CIA 1 timer A high byte
+        &ubyte  CIA1TBL         = $DC06        ; CIA 1 timer B low byte
+        &ubyte  CIA1TBH         = $DC07        ; CIA 1 timer B high byte
+        &ubyte  CIA1TOD10       = $DC08        ; time of day, 1/10 sec.
+        &ubyte  CIA1TODSEC      = $DC09        ; time of day, seconds
+        &ubyte  CIA1TODMMIN     = $DC0A        ; time of day, minutes
+        &ubyte  CIA1TODHR       = $DC0B        ; time of day, hours
+        &ubyte  CIA1SDR         = $DC0C        ; Serial Data Register
+        &ubyte  CIA1ICR         = $DC0D
+        &ubyte  CIA1CRA         = $DC0E
+        &ubyte  CIA1CRB         = $DC0F
 
-		&ubyte  CIA2PRA		= $DD00		; CIA 2 DRA, serial port and video address
-		&ubyte  CIA2PRB		= $DD01		; CIA 2 DRB, RS232 port / USERPORT
-		&ubyte  CIA2DDRA	= $DD02		; CIA 2 DDRA, serial port and video address
-		&ubyte  CIA2DDRB	= $DD03		; CIA 2 DDRB, RS232 port / USERPORT
-		&ubyte  CIA2TAL		= $DD04		; CIA 2 timer A low byte
-		&ubyte  CIA2TAH		= $DD05		; CIA 2 timer A high byte
-		&ubyte  CIA2TBL		= $DD06		; CIA 2 timer B low byte
-		&ubyte  CIA2TBH		= $DD07		; CIA 2 timer B high byte
-		&ubyte  CIA2TOD10	= $DD08		; time of day, 1/10 sec.
-		&ubyte  CIA2TODSEC	= $DD09		; time of day, seconds
-		&ubyte  CIA2TODMIN	= $DD0A		; time of day, minutes
-		&ubyte  CIA2TODHR	= $DD0B		; time of day, hours
-		&ubyte  CIA2SDR		= $DD0C		; Serial Data Register
-		&ubyte  CIA2ICR		= $DD0D
-		&ubyte  CIA2CRA		= $DD0E
-		&ubyte  CIA2CRB		= $DD0F
+        &ubyte  CIA2PRA         = $DD00        ; CIA 2 DRA, serial port and video address
+        &ubyte  CIA2PRB         = $DD01        ; CIA 2 DRB, RS232 port / USERPORT
+        &ubyte  CIA2DDRA        = $DD02        ; CIA 2 DDRA, serial port and video address
+        &ubyte  CIA2DDRB        = $DD03        ; CIA 2 DDRB, RS232 port / USERPORT
+        &ubyte  CIA2TAL         = $DD04        ; CIA 2 timer A low byte
+        &ubyte  CIA2TAH         = $DD05        ; CIA 2 timer A high byte
+        &ubyte  CIA2TBL         = $DD06        ; CIA 2 timer B low byte
+        &ubyte  CIA2TBH         = $DD07        ; CIA 2 timer B high byte
+        &ubyte  CIA2TOD10       = $DD08        ; time of day, 1/10 sec.
+        &ubyte  CIA2TODSEC      = $DD09        ; time of day, seconds
+        &ubyte  CIA2TODMIN      = $DD0A        ; time of day, minutes
+        &ubyte  CIA2TODHR       = $DD0B        ; time of day, hours
+        &ubyte  CIA2SDR         = $DD0C        ; Serial Data Register
+        &ubyte  CIA2ICR         = $DD0D
+        &ubyte  CIA2CRA         = $DD0E
+        &ubyte  CIA2CRB         = $DD0F
 
 ; ---- end of CIA registers ----
 
 ; ---- SID 6581/8580 registers ----
 
-		&ubyte  FREQLO1		= $D400		; channel 1 freq lo
-		&ubyte  FREQHI1		= $D401		; channel 1 freq hi
-		&uword  FREQ1		= $D400		; channel 1 freq (word)
-		&ubyte  PWLO1		= $D402		; channel 1 pulse width lo (7-0)
-		&ubyte  PWHI1		= $D403		; channel 1 pulse width hi (11-8)
-		&uword  PW1		= $D402		; channel 1 pulse width (word)
-		&ubyte  CR1		= $D404		; channel 1 voice control register
-		&ubyte  AD1		= $D405		; channel 1 attack & decay
-		&ubyte  SR1		= $D406		; channel 1 sustain & release
-		&ubyte  FREQLO2		= $D407		; channel 2 freq lo
-		&ubyte  FREQHI2		= $D408		; channel 2 freq hi
-		&uword  FREQ2		= $D407		; channel 2 freq (word)
-		&ubyte  PWLO2		= $D409		; channel 2 pulse width lo (7-0)
-		&ubyte  PWHI2		= $D40A		; channel 2 pulse width hi (11-8)
-		&uword  PW2		= $D409		; channel 2 pulse width (word)
-		&ubyte  CR2		= $D40B		; channel 2 voice control register
-		&ubyte  AD2		= $D40C		; channel 2 attack & decay
-		&ubyte  SR2		= $D40D		; channel 2 sustain & release
-		&ubyte  FREQLO3		= $D40E		; channel 3 freq lo
-		&ubyte  FREQHI3		= $D40F		; channel 3 freq hi
-		&uword  FREQ3		= $D40E		; channel 3 freq (word)
-		&ubyte  PWLO3		= $D410		; channel 3 pulse width lo (7-0)
-		&ubyte  PWHI3		= $D411		; channel 3 pulse width hi (11-8)
-		&uword  PW3		= $D410		; channel 3 pulse width (word)
-		&ubyte  CR3		= $D412		; channel 3 voice control register
-		&ubyte  AD3		= $D413		; channel 3 attack & decay
-		&ubyte  SR3		= $D414		; channel 3 sustain & release
-		&ubyte  FCLO		= $D415		; filter cutoff lo (2-0)
-		&ubyte  FCHI		= $D416		; filter cutoff hi (10-3)
-		&uword  FC		= $D415		; filter cutoff (word)
-		&ubyte  RESFILT		= $D417		; filter resonance and routing
-		&ubyte  MVOL		= $D418		; filter mode and main volume control
-		&ubyte  POTX		= $D419		; potentiometer X
-		&ubyte  POTY		= $D41A		; potentiometer Y
-		&ubyte  OSC3		= $D41B		; channel 3 oscillator value read
-		&ubyte  ENV3		= $D41C		; channel 3 envelope value read
+        &ubyte  FREQLO1         = $D400        ; channel 1 freq lo
+        &ubyte  FREQHI1         = $D401        ; channel 1 freq hi
+        &uword  FREQ1           = $D400        ; channel 1 freq (word)
+        &ubyte  PWLO1           = $D402        ; channel 1 pulse width lo (7-0)
+        &ubyte  PWHI1           = $D403        ; channel 1 pulse width hi (11-8)
+        &uword  PW1             = $D402        ; channel 1 pulse width (word)
+        &ubyte  CR1             = $D404        ; channel 1 voice control register
+        &ubyte  AD1             = $D405        ; channel 1 attack & decay
+        &ubyte  SR1             = $D406        ; channel 1 sustain & release
+        &ubyte  FREQLO2         = $D407        ; channel 2 freq lo
+        &ubyte  FREQHI2         = $D408        ; channel 2 freq hi
+        &uword  FREQ2           = $D407        ; channel 2 freq (word)
+        &ubyte  PWLO2           = $D409        ; channel 2 pulse width lo (7-0)
+        &ubyte  PWHI2           = $D40A        ; channel 2 pulse width hi (11-8)
+        &uword  PW2             = $D409        ; channel 2 pulse width (word)
+        &ubyte  CR2             = $D40B        ; channel 2 voice control register
+        &ubyte  AD2             = $D40C        ; channel 2 attack & decay
+        &ubyte  SR2             = $D40D        ; channel 2 sustain & release
+        &ubyte  FREQLO3         = $D40E        ; channel 3 freq lo
+        &ubyte  FREQHI3         = $D40F        ; channel 3 freq hi
+        &uword  FREQ3           = $D40E        ; channel 3 freq (word)
+        &ubyte  PWLO3           = $D410        ; channel 3 pulse width lo (7-0)
+        &ubyte  PWHI3           = $D411        ; channel 3 pulse width hi (11-8)
+        &uword  PW3             = $D410        ; channel 3 pulse width (word)
+        &ubyte  CR3             = $D412        ; channel 3 voice control register
+        &ubyte  AD3             = $D413        ; channel 3 attack & decay
+        &ubyte  SR3             = $D414        ; channel 3 sustain & release
+        &ubyte  FCLO            = $D415        ; filter cutoff lo (2-0)
+        &ubyte  FCHI            = $D416        ; filter cutoff hi (10-3)
+        &uword  FC              = $D415        ; filter cutoff (word)
+        &ubyte  RESFILT         = $D417        ; filter resonance and routing
+        &ubyte  MVOL            = $D418        ; filter mode and main volume control
+        &ubyte  POTX            = $D419        ; potentiometer X
+        &ubyte  POTY            = $D41A        ; potentiometer Y
+        &ubyte  OSC3            = $D41B        ; channel 3 oscillator value read
+        &ubyte  ENV3            = $D41C        ; channel 3 envelope value read
 
 ; ---- end of SID registers ----
 
@@ -186,8 +186,8 @@ c64 {
 
 ; ---- C64 basic routines ----
 
-asmsub	CLEARSCR	() clobbers(A,X,Y)		= $E544		; clear the screen
-asmsub	HOMECRSR	() clobbers(A,X,Y)		= $E566		; cursor to top left of screen
+romsub $E544 = CLEARSCR() clobbers(A,X,Y)       ; clear the screen
+romsub $E566 = HOMECRSR() clobbers(A,X,Y)       ; cursor to top left of screen
 
 
 ; ---- end of C64 basic routines ----
@@ -195,48 +195,48 @@ asmsub	HOMECRSR	() clobbers(A,X,Y)		= $E566		; cursor to top left of screen
 
 ; ---- C64 kernal routines ----
 
-asmsub	STROUT   (uword strptr @ AY) clobbers(A, X, Y)	= $AB1E		; print null-terminated string (use c64scr.print instead)
-asmsub	IRQDFRT  () clobbers(A,X,Y)			= $EA31		; default IRQ routine
-asmsub	IRQDFEND () clobbers(A,X,Y)			= $EA81		; default IRQ end/cleanup
-asmsub	CINT     () clobbers(A,X,Y)			= $FF81		; (alias: SCINIT) initialize screen editor and video chip
-asmsub	IOINIT   () clobbers(A, X)			= $FF84		; initialize I/O devices (CIA, SID, IRQ)
-asmsub	RAMTAS   () clobbers(A,X,Y)			= $FF87		; initialize RAM, tape buffer, screen
-asmsub	RESTOR   () clobbers(A,X,Y)			= $FF8A		; restore default I/O vectors
-asmsub	VECTOR   (uword userptr @ XY, ubyte dir @ Pc) clobbers(A,Y)  = $FF8D		; read/set I/O vector table
-asmsub	SETMSG   (ubyte value @ A)			= $FF90		; set Kernal message control flag
-asmsub	SECOND   (ubyte address @ A) clobbers(A)	= $FF93		; (alias: LSTNSA) send secondary address after LISTEN
-asmsub	TKSA     (ubyte address @ A) clobbers(A)	= $FF96		; (alias: TALKSA) send secondary address after TALK
-asmsub	MEMTOP   (uword address @ XY, ubyte dir @ Pc) -> uword @ XY	= $FF99		; read/set top of memory  pointer
-asmsub	MEMBOT   (uword address @ XY, ubyte dir @ Pc) -> uword @ XY	= $FF9C		; read/set bottom of memory  pointer
-asmsub	SCNKEY   () clobbers(A,X,Y)			= $FF9F		; scan the keyboard
-asmsub	SETTMO   (ubyte timeout @ A)			= $FFA2		; set time-out flag for IEEE bus
-asmsub	ACPTR    () -> ubyte @ A			= $FFA5		; (alias: IECIN) input byte from serial bus
-asmsub	CIOUT    (ubyte databyte @ A)			= $FFA8		; (alias: IECOUT) output byte to serial bus
-asmsub	UNTLK    () clobbers(A)				= $FFAB		; command serial bus device to UNTALK
-asmsub	UNLSN    () clobbers(A)				= $FFAE		; command serial bus device to UNLISTEN
-asmsub	LISTEN   (ubyte device @ A) clobbers(A)		= $FFB1		; command serial bus device to LISTEN
-asmsub	TALK     (ubyte device @ A) clobbers(A)		= $FFB4		; command serial bus device to TALK
-asmsub	READST   () -> ubyte @ A			= $FFB7		; read I/O status word
-asmsub	SETLFS   (ubyte logical @ A, ubyte device @ X, ubyte address @ Y) = $FFBA	; set logical file parameters
-asmsub	SETNAM   (ubyte namelen @ A, str filename @ XY)	= $FFBD		; set filename parameters
-asmsub	OPEN     () clobbers(A,X,Y)			= $FFC0		; (via 794 ($31A)) open a logical file
-asmsub	CLOSE    (ubyte logical @ A) clobbers(A,X,Y)	= $FFC3		; (via 796 ($31C)) close a logical file
-asmsub	CHKIN    (ubyte logical @ X) clobbers(A,X)	= $FFC6		; (via 798 ($31E)) define an input channel
-asmsub	CHKOUT   (ubyte logical @ X) clobbers(A,X)	= $FFC9		; (via 800 ($320)) define an output channel
-asmsub	CLRCHN   () clobbers(A,X)			= $FFCC		; (via 802 ($322)) restore default devices
-asmsub	CHRIN    () clobbers(Y) -> ubyte @ A		= $FFCF		; (via 804 ($324)) input a character (for keyboard, read a whole line from the screen) A=byte read.
-asmsub	CHROUT   (ubyte char @ A)			= $FFD2		; (via 806 ($326)) output a character
-asmsub	LOAD     (ubyte verify @ A, uword address @ XY) -> ubyte @Pc, ubyte @ A, ubyte @ X, ubyte @ Y = $FFD5	; (via 816 ($330)) load from device
-asmsub	SAVE     (ubyte zp_startaddr @ A, uword endaddr @ XY) -> ubyte @ Pc, ubyte @ A = $FFD8	; (via 818 ($332)) save to a device
-asmsub	SETTIM   (ubyte low @ A, ubyte middle @ X, ubyte high @ Y)	= $FFDB		; set the software clock
-asmsub	RDTIM    () -> ubyte @ A, ubyte @ X, ubyte @ Y	= $FFDE	; read the software clock
-asmsub	STOP     () clobbers(A,X) -> ubyte @ Pz, ubyte @ Pc	= $FFE1		; (via 808 ($328)) check the STOP key
-asmsub	GETIN    () clobbers(X,Y) -> ubyte @ A		= $FFE4		; (via 810 ($32A)) get a character
-asmsub	CLALL    () clobbers(A,X)			= $FFE7		; (via 812 ($32C)) close all files
-asmsub	UDTIM    () clobbers(A,X)			= $FFEA		; update the software clock
-asmsub	SCREEN   () -> ubyte @ X, ubyte @ Y		= $FFED		; read number of screen rows and columns
-asmsub	PLOT     (ubyte col @ Y, ubyte row @ X, ubyte dir @ Pc) -> ubyte @ X, ubyte @ Y	= $FFF0		; read/set position of cursor on screen.  Use c64scr.plot for a 'safe' wrapper that preserves X.
-asmsub	IOBASE   () -> uword @ XY			= $FFF3		; read base address of I/O devices
+romsub $AB1E = STROUT(uword strptr @ AY) clobbers(A, X, Y)      ; print null-terminated string (use c64scr.print instead)
+romsub $EA31 = IRQDFRT() clobbers(A,X,Y)                        ; default IRQ routine
+romsub $EA81 = IRQDFEND() clobbers(A,X,Y)                       ; default IRQ end/cleanup
+romsub $FF81 = CINT() clobbers(A,X,Y)                           ; (alias: SCINIT) initialize screen editor and video chip
+romsub $FF84 = IOINIT() clobbers(A, X)                          ; initialize I/O devices (CIA, SID, IRQ)
+romsub $FF87 = RAMTAS() clobbers(A,X,Y)                         ; initialize RAM, tape buffer, screen
+romsub $FF8A = RESTOR() clobbers(A,X,Y)                         ; restore default I/O vectors
+romsub $FF8D = VECTOR(uword userptr @ XY, ubyte dir @ Pc) clobbers(A,Y)     ; read/set I/O vector table
+romsub $FF90 = SETMSG(ubyte value @ A)                          ; set Kernal message control flag
+romsub $FF93 = SECOND(ubyte address @ A) clobbers(A)            ; (alias: LSTNSA) send secondary address after LISTEN
+romsub $FF96 = TKSA(ubyte address @ A) clobbers(A)              ; (alias: TALKSA) send secondary address after TALK
+romsub $FF99 = MEMTOP(uword address @ XY, ubyte dir @ Pc) -> uword @ XY     ; read/set top of memory  pointer
+romsub $FF9C = MEMBOT(uword address @ XY, ubyte dir @ Pc) -> uword @ XY     ; read/set bottom of memory  pointer
+romsub $FF9F = SCNKEY() clobbers(A,X,Y)                         ; scan the keyboard
+romsub $FFA2 = SETTMO(ubyte timeout @ A)                        ; set time-out flag for IEEE bus
+romsub $FFA5 = ACPTR() -> ubyte @ A                             ; (alias: IECIN) input byte from serial bus
+romsub $FFA8 = CIOUT(ubyte databyte @ A)                        ; (alias: IECOUT) output byte to serial bus
+romsub $FFAB = UNTLK() clobbers(A)                              ; command serial bus device to UNTALK
+romsub $FFAE = UNLSN() clobbers(A)                              ; command serial bus device to UNLISTEN
+romsub $FFB1 = LISTEN(ubyte device @ A) clobbers(A)             ; command serial bus device to LISTEN
+romsub $FFB4 = TALK(ubyte device @ A) clobbers(A)               ; command serial bus device to TALK
+romsub $FFB7 = READST() -> ubyte @ A                            ; read I/O status word
+romsub $FFBA = SETLFS(ubyte logical @ A, ubyte device @ X, ubyte address @ Y)   ; set logical file parameters
+romsub $FFBD = SETNAM(ubyte namelen @ A, str filename @ XY)     ; set filename parameters
+romsub $FFC0 = OPEN() clobbers(A,X,Y)                           ; (via 794 ($31A)) open a logical file
+romsub $FFC3 = CLOSE(ubyte logical @ A) clobbers(A,X,Y)         ; (via 796 ($31C)) close a logical file
+romsub $FFC6 = CHKIN(ubyte logical @ X) clobbers(A,X)           ; (via 798 ($31E)) define an input channel
+romsub $FFC9 = CHKOUT(ubyte logical @ X) clobbers(A,X)          ; (via 800 ($320)) define an output channel
+romsub $FFCC = CLRCHN() clobbers(A,X)                           ; (via 802 ($322)) restore default devices
+romsub $FFCF = CHRIN() clobbers(Y) -> ubyte @ A                 ; (via 804 ($324)) input a character (for keyboard, read a whole line from the screen) A=byte read.
+romsub $FFD2 = CHROUT(ubyte char @ A)                           ; (via 806 ($326)) output a character
+romsub $FFD5 = LOAD(ubyte verify @ A, uword address @ XY) -> ubyte @Pc, ubyte @ A, ubyte @ X, ubyte @ Y     ; (via 816 ($330)) load from device
+romsub $FFD8 = SAVE(ubyte zp_startaddr @ A, uword endaddr @ XY) -> ubyte @ Pc, ubyte @ A                    ; (via 818 ($332)) save to a device
+romsub $FFDB = SETTIM(ubyte low @ A, ubyte middle @ X, ubyte high @ Y)      ; set the software clock
+romsub $FFDE = RDTIM() -> ubyte @ A, ubyte @ X, ubyte @ Y       ; read the software clock
+romsub $FFE1 = STOP() clobbers(A,X) -> ubyte @ Pz, ubyte @ Pc   ; (via 808 ($328)) check the STOP key
+romsub $FFE4 = GETIN() clobbers(X,Y) -> ubyte @ A               ; (via 810 ($32A)) get a character
+romsub $FFE7 = CLALL() clobbers(A,X)                            ; (via 812 ($32C)) close all files
+romsub $FFEA = UDTIM() clobbers(A,X)                            ; update the software clock
+romsub $FFED = SCREEN() -> ubyte @ X, ubyte @ Y                 ; read number of screen rows and columns
+romsub $FFF0 = PLOT(ubyte col @ Y, ubyte row @ X, ubyte dir @ Pc) -> ubyte @ X, ubyte @ Y       ; read/set position of cursor on screen.  Use c64scr.plot for a 'safe' wrapper that preserves X.
+romsub $FFF3 = IOBASE() -> uword @ XY                           ; read base address of I/O devices
 
 ; ---- end of C64 kernal routines ----
 

compiler/res/prog8lib/c64utils.p8

@@ -15,28 +15,199 @@ c64utils {
 		const   uword  ESTACK_HI	= $cf00
 
 
-; ----- utility functions ----
+; ----- number conversions to decimal strings
 
-asmsub  ubyte2decimal  (ubyte value @ A) -> ubyte @ Y, ubyte @ X, ubyte @ A  {
-	; ---- A to decimal string in Y/X/A  (100s in Y, 10s in X, 1s in A)
-	%asm {{
-		ldy  #$2f
-		ldx  #$3a
-		sec
--               iny
-		sbc  #100
-		bcs  -
--               dex
-		adc  #10
-		bmi  -
-		adc  #$2f
-		rts
+asmsub  ubyte2decimal  (ubyte value @ A) -> ubyte @ Y, ubyte @ A, ubyte @ X  {
+	; ---- A to decimal string in Y/A/X  (100s in Y, 10s in A, 1s in X)
+    %asm {{
+        ldy  #uword2decimal.ASCII_0_OFFSET
+        bne  uword2decimal.hex_try200
+        rts
 	}}
 }
 
-asmsub  byte2decimal  (ubyte value @ A) -> ubyte @ Y, ubyte @ X, ubyte @ A  {
-	; ---- A (signed byte) to decimal string in Y/X/A  (100s in Y, 10s in X, 1s in A)
-	;      note: the '-' is not part of the conversion here if it's a negative number
+asmsub  uword2decimal  (uword value @ AY) -> ubyte @Y, ubyte @A, ubyte @X  {
+    ;  ---- convert 16 bit uword in A/Y to decimal
+    ;  output in uword2decimal.decTenThousands, decThousands, decHundreds, decTens, decOnes
+    ;  (these are terminated by a zero byte so they can be easily printed)
+    ;  also returns Y = 100's, A = 10's, X = 1's
+
+    %asm {{
+
+;Convert 16 bit Hex to Decimal (0-65535) Rev 2
+;By Omegamatrix    Further optimizations by tepples
+; routine from http://forums.nesdev.com/viewtopic.php?f=2&t=11341&start=15
+
+;HexToDec99
+; start in A
+; end with A = 10's, decOnes (also in X)
+
+;HexToDec255
+; start in A
+; end with Y = 100's, A = 10's, decOnes (also in X)
+
+;HexToDec999
+; start with A = high byte, Y = low byte
+; end with Y = 100's, A = 10's, decOnes (also in X)
+; requires 1 extra temp register on top of decOnes, could combine
+; these two if HexToDec65535 was eliminated...
+
+;HexToDec65535
+; start with A/Y (low/high) as 16 bit value
+; end with decTenThousand, decThousand, Y = 100's, A = 10's, decOnes (also in X)
+; (irmen: I store Y and A in decHundreds and decTens too, so all of it can be easily printed)
+
+
+ASCII_0_OFFSET 	= $30
+temp       	    = c64.SCRATCH_ZPB1	; byte in zeropage
+hexHigh      	= c64.SCRATCH_ZPWORD1	; byte in zeropage
+hexLow       	= c64.SCRATCH_ZPWORD1+1	; byte in zeropage
+
+
+HexToDec65535; SUBROUTINE
+    sty    hexHigh               ;3  @9
+    sta    hexLow                ;3  @12
+    tya
+    tax                          ;2  @14
+    lsr    a                     ;2  @16
+    lsr    a                     ;2  @18   integer divide 1024 (result 0-63)
+
+    cpx    #$A7                  ;2  @20   account for overflow of multiplying 24 from 43,000 ($A7F8) onward,
+    adc    #1                    ;2  @22   we can just round it to $A700, and the divide by 1024 is fine...
+
+    ;at this point we have a number 1-65 that we have to times by 24,
+    ;add to original sum, and Mod 1024 to get a remainder 0-999
+
+
+    sta    temp                  ;3  @25
+    asl    a                     ;2  @27
+    adc    temp                  ;3  @30  x3
+    tay                          ;2  @32
+    lsr    a                     ;2  @34
+    lsr    a                     ;2  @36
+    lsr    a                     ;2  @38
+    lsr    a                     ;2  @40
+    lsr    a                     ;2  @42
+    tax                          ;2  @44
+    tya                          ;2  @46
+    asl    a                     ;2  @48
+    asl    a                     ;2  @50
+    asl    a                     ;2  @52
+    clc                          ;2  @54
+    adc    hexLow                ;3  @57
+    sta    hexLow                ;3  @60
+    txa                          ;2  @62
+    adc    hexHigh               ;3  @65
+    sta    hexHigh               ;3  @68
+    ror    a                     ;2  @70
+    lsr    a                     ;2  @72
+    tay                          ;2  @74    integer divide 1,000 (result 0-65)
+
+    lsr    a                     ;2  @76    split the 1,000 and 10,000 digit
+    tax                          ;2  @78
+    lda    ShiftedBcdTab,x       ;4  @82
+    tax                          ;2  @84
+    rol    a                     ;2  @86
+    and    #$0F                  ;2  @88
+    ora    #ASCII_0_OFFSET
+    sta    decThousands          ;3  @91
+    txa                          ;2  @93
+    lsr    a                     ;2  @95
+    lsr    a                     ;2  @97
+    lsr    a                     ;2  @99
+    ora    #ASCII_0_OFFSET
+    sta    decTenThousands       ;3  @102
+
+    lda    hexLow                ;3  @105
+    cpy    temp                  ;3  @108
+    bmi    _doSubtract           ;2³ @110/111
+    beq    _useZero               ;2³ @112/113
+    adc    #23 + 24              ;2  @114
+_doSubtract
+    sbc    #23                   ;2  @116
+    sta    hexLow                ;3  @119
+_useZero
+    lda    hexHigh               ;3  @122
+    sbc    #0                    ;2  @124
+
+Start100s
+    and    #$03                  ;2  @126
+    tax                          ;2  @128   0,1,2,3
+    cmp    #2                    ;2  @130
+    rol    a                     ;2  @132   0,2,5,7
+    ora    #ASCII_0_OFFSET
+    tay                          ;2  @134   Y = Hundreds digit
+
+    lda    hexLow                ;3  @137
+    adc    Mod100Tab,x           ;4  @141    adding remainder of 256, 512, and 256+512 (all mod 100)
+    bcs    hex_doSub200             ;2³ @143/144
+
+hex_try200
+    cmp    #200                  ;2  @145
+    bcc    hex_try100               ;2³ @147/148
+hex_doSub200
+    iny                          ;2  @149
+    iny                          ;2  @151
+    sbc    #200                  ;2  @153
+hex_try100
+    cmp    #100                  ;2  @155
+    bcc    HexToDec99            ;2³ @157/158
+    iny                          ;2  @159
+    sbc    #100                  ;2  @161
+
+HexToDec99; SUBROUTINE
+    lsr    a                     ;2  @163
+    tax                          ;2  @165
+    lda    ShiftedBcdTab,x       ;4  @169
+    tax                          ;2  @171
+    rol    a                     ;2  @173
+    and    #$0F                  ;2  @175
+    ora    #ASCII_0_OFFSET
+    sta    decOnes               ;3  @178
+    txa                          ;2  @180
+    lsr    a                     ;2  @182
+    lsr    a                     ;2  @184
+    lsr    a                     ;2  @186
+    ora    #ASCII_0_OFFSET
+
+    ; irmen: load X with ones, and store Y and A too, for easy printing afterwards
+    sty  decHundreds
+    sta  decTens
+    ldx  decOnes
+    rts                          ;6  @192   Y=hundreds, A = tens digit, X=ones digit
+
+
+HexToDec999; SUBROUTINE
+    sty    hexLow                ;3  @9
+    jmp    Start100s             ;3  @12
+
+Mod100Tab
+    .byte 0,56,12,56+12
+
+ShiftedBcdTab
+    .byte $00,$01,$02,$03,$04,$08,$09,$0A,$0B,$0C
+    .byte $10,$11,$12,$13,$14,$18,$19,$1A,$1B,$1C
+    .byte $20,$21,$22,$23,$24,$28,$29,$2A,$2B,$2C
+    .byte $30,$31,$32,$33,$34,$38,$39,$3A,$3B,$3C
+    .byte $40,$41,$42,$43,$44,$48,$49,$4A,$4B,$4C
+
+decTenThousands   	.byte  0
+decThousands    	.byte  0
+decHundreds		.byte  0
+decTens			.byte  0
+decOnes   		.byte  0
+			.byte  0		; zero-terminate the decimal output string
+
+    }}
+}
+
+
+; ----- utility functions ----
+
+
+asmsub  byte2decimal  (byte value @ A) -> ubyte @ Y, ubyte @ A, ubyte @ X  {
+	; ---- A (signed byte) to decimal string in Y/A/X  (100s in Y, 10s in A, 1s in X)
+	;      note: if the number is negative, you have to deal with the '-' yourself!
 	%asm {{
 		cmp  #0
 		bpl  +
@@ -48,7 +219,7 @@ asmsub  byte2decimal  (ubyte value @ A) -> ubyte @ Y, ubyte @ X, ubyte @ A  {
 }
 
 asmsub  ubyte2hex  (ubyte value @ A) -> ubyte @ A, ubyte @ Y  {
-	; ---- A to hex string in AY (first hex char in A, second hex char in Y)
+	; ---- A to hex petscii string in AY (first hex char in A, second hex char in Y)
 	%asm {{
 		stx  c64.SCRATCH_ZPREGX
 		pha
@@ -69,7 +240,6 @@ _hex_digits	.text "0123456789abcdef"	; can probably be reused for other stuff as
 	}}
 }
 
-
 asmsub  uword2hex  (uword value @ AY) clobbers(A,Y)  {
 	; ---- convert 16 bit uword in A/Y into 4-character hexadecimal string 'uword2hex.output' (0-terminated)
 	%asm {{
@@ -87,92 +257,6 @@ output	.text  "0000", $00      ; 0-terminated output buffer (to make printing ea
 	}}
 }
 
-asmsub  uword2bcd  (uword value @ AY) clobbers(A,Y)  {
-	; Convert an 16 bit binary value to BCD
-	;
-	; This function converts a 16 bit binary value in A/Y into a 24 bit BCD. It
-	; works by transferring one bit a time from the source and adding it
-	; into a BCD value that is being doubled on each iteration. As all the
-	; arithmetic is being done in BCD the result is a binary to decimal
-	; conversion.
-	%asm {{
-		sta  c64.SCRATCH_ZPB1
-		sty  c64.SCRATCH_ZPREG
-		php
-		pla             ; read status register
-		and  #%00000100
-		sta  _had_irqd
-		sei				; disable interrupts because of bcd math
-		sed				; switch to decimal mode
-		lda  #0				; ensure the result is clear
-		sta  bcdbuff+0
-		sta  bcdbuff+1
-		sta  bcdbuff+2
-		ldy  #16			; the number of source bits
-
--		asl  c64.SCRATCH_ZPB1		; shift out one bit
-		rol  c64.SCRATCH_ZPREG
-		lda  bcdbuff+0		; and add into result
-		adc  bcdbuff+0
-		sta  bcdbuff+0
-		lda  bcdbuff+1		; propagating any carry
-		adc  bcdbuff+1
-		sta  bcdbuff+1
-		lda  bcdbuff+2		; ... thru whole result
-		adc  bcdbuff+2
-		sta  bcdbuff+2
-		dey				; and repeat for next bit
-		bne  -
-		cld				; back to binary
-		lda  _had_irqd
-		bne  +
-		cli				; enable interrupts again (only if they were enabled before)
-+		rts
-_had_irqd  .byte  0
-bcdbuff  .byte  0,0,0
-	}}
-}
-
-
-asmsub  uword2decimal  (uword value @ AY) clobbers(A) -> ubyte @ Y  {
-	; ---- convert 16 bit uword in A/Y into 0-terminated decimal string into memory  'uword2decimal.output'
-	;      returns length of resulting string in Y
-	%asm {{
-		jsr  uword2bcd
-		lda  uword2bcd.bcdbuff+2
-		clc
-		adc  #'0'
-		sta  output
-		ldy  #1
-		lda  uword2bcd.bcdbuff+1
-		jsr  +
-		lda  uword2bcd.bcdbuff+0
-
-+		pha
-		lsr  a
-		lsr  a
-		lsr  a
-		lsr  a
-		clc
-		adc  #'0'
-		sta  output,y
-		iny
-		pla
-		and  #$0f
-		adc  #'0'
-		sta  output,y
-		iny
-		lda  #0
-		sta  output,y
-		rts
-
-output  .text  "00000", $00     ; 0 terminated
-
-	}}
-
-}
-
-
 asmsub str2uword(str string @ AY) -> uword @ AY {
 	; -- returns the unsigned word value of the string number argument in AY
 	;    the number may NOT be preceded by a + sign and may NOT contain spaces
@@ -227,7 +311,6 @@ _result_times_10     ; (W*4 + W)*2
 	}}
 }
 
-
 asmsub str2word(str string @ AY) -> word @ AY {
 	; -- returns the signed word value of the string number argument in AY
 	;    the number may be preceded by a + or - sign but may NOT contain spaces
@@ -283,7 +366,6 @@ _negative	.byte  0
 	}}
 }
 
-
 asmsub  set_irqvec_excl() clobbers(A)  {
 	%asm {{
 		sei
@@ -341,6 +423,7 @@ _irq_handler_init
 		dex
 		dex
 		dex
+		cld
 		rts
 
 _irq_handler_end
@@ -372,7 +455,6 @@ IRQ_SCRATCH_ZPWORD2	.word  0
 		}}
 }
 
-
 asmsub  restore_irqvec() {
 	%asm {{
 		sei
@@ -389,7 +471,6 @@ asmsub  restore_irqvec() {
 	}}
 }
 
-
 asmsub  set_rasterirq(uword rasterpos @ AY) clobbers(A) {
 	%asm {{
 		sei
@@ -454,13 +535,11 @@ _raster_irq_handler
 }
 
 
-
 }  ; ------ end of block c64utils
 
 
 
 
-
 c64scr {
 	; ---- this block contains (character) Screen and text I/O related functions ----
 
@@ -480,21 +559,15 @@ asmsub  clear_screen (ubyte char @ A, ubyte color @ Y) clobbers(A)  {
 
 }
 
-
 asmsub  clear_screenchars (ubyte char @ A) clobbers(Y)  {
 	; ---- clear the character screen with the given fill character (leaves colors)
 	;      (assumes screen matrix is at the default address)
 	%asm {{
 		ldy  #0
 _loop		sta  c64.Screen,y
-		sta  c64.Screen+1,y
 		sta  c64.Screen+$0100,y
-		sta  c64.Screen+$0101,y
 		sta  c64.Screen+$0200,y
-		sta  c64.Screen+$0201,y
 		sta  c64.Screen+$02e8,y
-		sta  c64.Screen+$02e9,y
-		iny
 		iny
 		bne  _loop
 		rts
@@ -507,25 +580,20 @@ asmsub  clear_screencolors (ubyte color @ A) clobbers(Y)  {
 	%asm {{
 		ldy  #0
 _loop		sta  c64.Colors,y
-		sta  c64.Colors+1,y
 		sta  c64.Colors+$0100,y
-		sta  c64.Colors+$0101,y
 		sta  c64.Colors+$0200,y
-		sta  c64.Colors+$0201,y
 		sta  c64.Colors+$02e8,y
-		sta  c64.Colors+$02e9,y
-		iny
 		iny
 		bne  _loop
 		rts
         }}
 }
 
-
 asmsub  scroll_left_full  (ubyte alsocolors @ Pc) clobbers(A, Y)  {
 	; ---- scroll the whole screen 1 character to the left
 	;      contents of the rightmost column are unchanged, you should clear/refill this yourself
 	;      Carry flag determines if screen color data must be scrolled too
+
 	%asm {{
 		stx  c64.SCRATCH_ZPREGX
 		bcs  +
@@ -535,18 +603,7 @@ asmsub  scroll_left_full  (ubyte alsocolors @ Pc) clobbers(A, Y)  {
 		ldx  #0
 		ldy  #38
 -
-	.for row=0, row<=12, row+=1
-		lda  c64.Colors + 40*row + 1,x
-		sta  c64.Colors + 40*row,x
-	.next
-		inx
-		dey
-		bpl  -
-
-		ldx  #0
-		ldy  #38
--
-	.for row=13, row<=24, row+=1
+	.for row=0, row<=24, row+=1
 		lda  c64.Colors + 40*row + 1,x
 		sta  c64.Colors + 40*row,x
 	.next
@@ -558,18 +615,7 @@ _scroll_screen  ; scroll the screen memory
 		ldx  #0
 		ldy  #38
 -
-	.for row=0, row<=12, row+=1
-		lda  c64.Screen + 40*row + 1,x
-		sta  c64.Screen + 40*row,x
-	.next
-		inx
-		dey
-		bpl  -
-
-		ldx  #0
-		ldy  #38
--
-	.for row=13, row<=24, row+=1
+	.for row=0, row<=24, row+=1
 		lda  c64.Screen + 40*row + 1,x
 		sta  c64.Screen + 40*row,x
 	.next
@@ -582,7 +628,6 @@ _scroll_screen  ; scroll the screen memory
 	}}
 }
 
-
 asmsub  scroll_right_full  (ubyte alsocolors @ Pc) clobbers(A)  {
 	; ---- scroll the whole screen 1 character to the right
 	;      contents of the leftmost column are unchanged, you should clear/refill this yourself
@@ -595,47 +640,28 @@ asmsub  scroll_right_full  (ubyte alsocolors @ Pc) clobbers(A)  {
 +               ; scroll the color memory
 		ldx  #38
 -
-	.for row=0, row<=12, row+=1
+	.for row=0, row<=24, row+=1
 		lda  c64.Colors + 40*row + 0,x
 		sta  c64.Colors + 40*row + 1,x
 	.next
 		dex
 		bpl  -
 
-		ldx  #38
--
-	.for row=13, row<=24, row+=1
-		lda  c64.Colors + 40*row,x
-		sta  c64.Colors + 40*row + 1,x
-	.next
-		dex
-		bpl  -
-
 _scroll_screen  ; scroll the screen memory
 		ldx  #38
 -
-	.for row=0, row<=12, row+=1
+	.for row=0, row<=24, row+=1
 		lda  c64.Screen + 40*row + 0,x
 		sta  c64.Screen + 40*row + 1,x
 	.next
 		dex
 		bpl  -
 
-		ldx  #38
--
-	.for row=13, row<=24, row+=1
-		lda  c64.Screen + 40*row,x
-		sta  c64.Screen + 40*row + 1,x
-	.next
-		dex
-		bpl  -
-
 		ldx  c64.SCRATCH_ZPREGX
 		rts
 	}}
 }
 
-
 asmsub  scroll_up_full  (ubyte alsocolors @ Pc) clobbers(A)  {
 	; ---- scroll the whole screen 1 character up
 	;      contents of the bottom row are unchanged, you should refill/clear this yourself
@@ -648,16 +674,7 @@ asmsub  scroll_up_full  (ubyte alsocolors @ Pc) clobbers(A)  {
 +               ; scroll the color memory
 		ldx #39
 -
-	.for row=1, row<=11, row+=1
-		lda  c64.Colors + 40*row,x
-		sta  c64.Colors + 40*(row-1),x
-	.next
-		dex
-		bpl  -
-
-		ldx #39
--
-	.for row=12, row<=24, row+=1
+	.for row=1, row<=24, row+=1
 		lda  c64.Colors + 40*row,x
 		sta  c64.Colors + 40*(row-1),x
 	.next
@@ -667,16 +684,7 @@ asmsub  scroll_up_full  (ubyte alsocolors @ Pc) clobbers(A)  {
 _scroll_screen  ; scroll the screen memory
 		ldx #39
 -
-	.for row=1, row<=11, row+=1
-		lda  c64.Screen + 40*row,x
-		sta  c64.Screen + 40*(row-1),x
-	.next
-		dex
-		bpl  -
-
-		ldx #39
--
-	.for row=12, row<=24, row+=1
+	.for row=1, row<=24, row+=1
 		lda  c64.Screen + 40*row,x
 		sta  c64.Screen + 40*(row-1),x
 	.next
@@ -688,7 +696,6 @@ _scroll_screen  ; scroll the screen memory
 	}}
 }
 
-
 asmsub  scroll_down_full  (ubyte alsocolors @ Pc) clobbers(A)  {
 	; ---- scroll the whole screen 1 character down
 	;      contents of the top row are unchanged, you should refill/clear this yourself
@@ -701,16 +708,7 @@ asmsub  scroll_down_full  (ubyte alsocolors @ Pc) clobbers(A)  {
 +               ; scroll the color memory
 		ldx #39
 -
-	.for row=23, row>=12, row-=1
-		lda  c64.Colors + 40*row,x
-		sta  c64.Colors + 40*(row+1),x
-	.next
-		dex
-		bpl  -
-
-		ldx #39
--
-	.for row=11, row>=0, row-=1
+	.for row=23, row>=0, row-=1
 		lda  c64.Colors + 40*row,x
 		sta  c64.Colors + 40*(row+1),x
 	.next
@@ -720,16 +718,7 @@ asmsub  scroll_down_full  (ubyte alsocolors @ Pc) clobbers(A)  {
 _scroll_screen  ; scroll the screen memory
 		ldx #39
 -
-	.for row=23, row>=12, row-=1
-		lda  c64.Screen + 40*row,x
-		sta  c64.Screen + 40*(row+1),x
-	.next
-		dex
-		bpl  -
-
-		ldx #39
--
-	.for row=11, row>=0, row-=1
+	.for row=23, row>=0, row-=1
 		lda  c64.Screen + 40*row,x
 		sta  c64.Screen + 40*(row+1),x
 	.next
@@ -742,7 +731,6 @@ _scroll_screen  ; scroll the screen memory
 }
 
 
-
 asmsub  print (str text @ AY) clobbers(A,Y)  {
 	; ---- print null terminated string from A/Y
 	; note: the compiler contains an optimization that will replace
@@ -761,7 +749,6 @@ asmsub  print (str text @ AY) clobbers(A,Y)  {
 	}}
 }
 
-
 asmsub  print_ub0  (ubyte value @ A) clobbers(A,Y)  {
 	; ---- print the ubyte in A in decimal form, with left padding 0s (3 positions total)
 	%asm {{
@@ -770,16 +757,15 @@ asmsub  print_ub0  (ubyte value @ A) clobbers(A,Y)  {
 		pha
 		tya
 		jsr  c64.CHROUT
-		txa
-		jsr  c64.CHROUT
 		pla
 		jsr  c64.CHROUT
+		txa
+		jsr  c64.CHROUT
 		ldx  c64.SCRATCH_ZPREGX
 		rts
 	}}
 }
 
-
 asmsub  print_ub  (ubyte value @ A) clobbers(A,Y)  {
 	; ---- print the ubyte in A in decimal form, without left padding 0s
 	%asm {{
@@ -788,15 +774,17 @@ asmsub  print_ub  (ubyte value @ A) clobbers(A,Y)  {
 _print_byte_digits
 		pha
 		cpy  #'0'
-		bne  _print_hundreds
-		cpx  #'0'
-		bne  _print_tens
-		jmp  _end
-_print_hundreds	tya
+		beq  +
+		tya
 		jsr  c64.CHROUT
-_print_tens	txa
+		pla
 		jsr  c64.CHROUT
-_end		pla
+		jmp  _ones
++       pla
+        cmp  #'0'
+        beq  _ones
+        jsr  c64.CHROUT
+_ones   txa
 		jsr  c64.CHROUT
 		ldx  c64.SCRATCH_ZPREGX
 		rts
@@ -820,7 +808,6 @@ asmsub  print_b  (byte value @ A) clobbers(A,Y)  {
 	}}
 }
 
-
 asmsub  print_ubhex  (ubyte value @ A, ubyte prefix @ Pc) clobbers(A,Y)  {
 	; ---- print the ubyte in A in hex form (if Carry is set, a radix prefix '$' is printed as well)
 	%asm {{
@@ -839,7 +826,6 @@ asmsub  print_ubhex  (ubyte value @ A, ubyte prefix @ Pc) clobbers(A,Y)  {
 	}}
 }
 
-
 asmsub  print_ubbin  (ubyte value @ A, ubyte prefix @ Pc) clobbers(A,Y)  {
 	; ---- print the ubyte in A in binary form (if Carry is set, a radix prefix '%' is printed as well)
 	%asm {{
@@ -861,7 +847,6 @@ asmsub  print_ubbin  (ubyte value @ A, ubyte prefix @ Pc) clobbers(A,Y)  {
 	}}
 }
 
-
 asmsub  print_uwbin  (uword value @ AY, ubyte prefix @ Pc) clobbers(A,Y)  {
 	; ---- print the uword in A/Y in binary form (if Carry is set, a radix prefix '%' is printed as well)
 	%asm {{
@@ -874,7 +859,6 @@ asmsub  print_uwbin  (uword value @ AY, ubyte prefix @ Pc) clobbers(A,Y)  {
 	}}
 }
 
-
 asmsub print_uwhex  (uword value @ AY, ubyte prefix @ Pc) clobbers(A,Y)  {
 	; ---- print the uword in A/Y in hexadecimal form (4 digits)
 	;      (if Carry is set, a radix prefix '$' is printed as well)
@@ -888,51 +872,45 @@ asmsub print_uwhex  (uword value @ AY, ubyte prefix @ Pc) clobbers(A,Y)  {
 	}}
 }
 
-
 asmsub  print_uw0  (uword value @ AY) clobbers(A,Y)  {
 	; ---- print the uword in A/Y in decimal form, with left padding 0s (5 positions total)
 	%asm {{
+	    stx  c64.SCRATCH_ZPREGX
 		jsr  c64utils.uword2decimal
 		ldy  #0
--		lda  c64utils.uword2decimal.output,y
+-		lda  c64utils.uword2decimal.decTenThousands,y
+        beq  +
 		jsr  c64.CHROUT
 		iny
-		cpy  #5
 		bne  -
++		ldx  c64.SCRATCH_ZPREGX
 		rts
 	}}
 }
 
-
 asmsub  print_uw  (uword value @ AY) clobbers(A,Y)  {
 	; ---- print the uword in A/Y in decimal form, without left padding 0s
 	%asm {{
+	    stx  c64.SCRATCH_ZPREGX
 		jsr  c64utils.uword2decimal
+		ldx  c64.SCRATCH_ZPREGX
 		ldy  #0
-		lda  c64utils.uword2decimal.output
+-		lda  c64utils.uword2decimal.decTenThousands,y
+		beq  _allzero
 		cmp  #'0'
-		bne  _pr_decimal
-		iny
-		lda  c64utils.uword2decimal.output+1
-		cmp  #'0'
-		bne  _pr_decimal
-		iny
-		lda  c64utils.uword2decimal.output+2
-		cmp  #'0'
-		bne  _pr_decimal
-		iny
-		lda  c64utils.uword2decimal.output+3
-		cmp  #'0'
-		bne  _pr_decimal
+		bne  _gotdigit
 		iny
+		bne  -
 
-_pr_decimal
-		lda  c64utils.uword2decimal.output,y
+_gotdigit
 		jsr  c64.CHROUT
 		iny
-		cpy  #5
-		bcc  _pr_decimal
+		lda  c64utils.uword2decimal.decTenThousands,y
+		bne  _gotdigit
 		rts
+_allzero
+        lda  #'0'
+        jmp  c64.CHROUT
 	}}
 }
 

compiler/res/prog8lib/math.asm

@@ -239,7 +239,7 @@ mul_byte_3	.proc
 		sta  c64.ESTACK_LO+1,x
 		rts
 		.pend
-		
+
 mul_word_3	.proc
 		; W*2 + W
 		lda  c64.ESTACK_HI+1,x
@@ -255,7 +255,7 @@ mul_word_3	.proc
 		sta  c64.ESTACK_HI+1,x
 		rts
 		.pend
-		
+
 
 mul_byte_5	.proc
 		; X*4 + X
@@ -286,7 +286,7 @@ mul_word_5	.proc
 		rts
 		.pend
 
-		
+
 mul_byte_6	.proc
 		; (X*2 + X)*2
 		lda  c64.ESTACK_LO+1,x
@@ -327,7 +327,7 @@ mul_byte_7	.proc
 		sta  c64.ESTACK_LO+1,x
 		rts
 		.pend
-		
+
 mul_word_7	.proc
 		; W*8 - W
 		lda  c64.ESTACK_HI+1,x
@@ -411,7 +411,7 @@ mul_word_10	.proc
 		sta  c64.ESTACK_HI+1,x
 		rts
 		.pend
-		
+
 mul_byte_11	.proc
 		; (X*2 + X)*4 - X
 		lda  c64.ESTACK_LO+1,x
@@ -488,7 +488,7 @@ mul_byte_14	.proc
 		sta  c64.ESTACK_LO+1,x
 		rts
 		.pend
-		
+
 ; mul_word_14 is skipped (too much code)
 
 mul_byte_15	.proc
@@ -604,7 +604,7 @@ mul_word_25	.proc
 		adc  c64.ESTACK_HI+1,x
 		sta  c64.ESTACK_HI+1,x
 		rts
-		.pend		
+		.pend
 
 mul_byte_40	.proc
 		; (X*4 + X)*8
@@ -619,7 +619,7 @@ mul_byte_40	.proc
 		sta  c64.ESTACK_LO+1,x
 		rts
 		.pend
-		
+
 mul_word_40	.proc
 		; (W*4 + W)*8
 		lda  c64.ESTACK_HI+1,x
@@ -643,3 +643,229 @@ mul_word_40	.proc
 		sta  c64.ESTACK_HI+1,x
 		rts
 		.pend
+
+sign_b		.proc
+		lda  c64.ESTACK_LO+1,x
+		beq  _sign_zero
+		bmi  _sign_neg
+_sign_pos	lda  #1
+		sta  c64.ESTACK_LO+1,x
+		rts
+_sign_neg	lda  #-1
+_sign_zero	sta  c64.ESTACK_LO+1,x
+		rts
+		.pend
+
+sign_ub		.proc
+		lda  c64.ESTACK_LO+1,x
+		beq  sign_b._sign_zero
+		bne  sign_b._sign_pos
+		.pend
+
+sign_w		.proc
+		lda  c64.ESTACK_HI+1,x
+		bmi  sign_b._sign_neg
+		beq  sign_ub
+		bne  sign_b._sign_pos
+		.pend
+
+sign_uw		.proc
+		lda  c64.ESTACK_HI+1,x
+		beq  _sign_possibly_zero
+_sign_pos	lda  #1
+		sta  c64.ESTACK_LO+1,x
+		rts
+_sign_possibly_zero	lda  c64.ESTACK_LO+1,x
+		bne  _sign_pos
+		sta  c64.ESTACK_LO+1,x
+		rts
+		.pend
+
+
+
+; bit shifts.
+; anything below 3 is done inline. anything above 7 is done via other optimizations.
+
+shift_left_w_7	.proc
+		lda  c64.ESTACK_HI+1,x
+		sta  c64.SCRATCH_ZPB1
+		lda  c64.ESTACK_LO+1,x
+
+		asl  a
+		rol  c64.SCRATCH_ZPB1
+_shift6		asl  a
+		rol  c64.SCRATCH_ZPB1
+_shift5		asl  a
+		rol  c64.SCRATCH_ZPB1
+_shift4		asl  a
+		rol  c64.SCRATCH_ZPB1
+_shift3		asl  a
+		rol  c64.SCRATCH_ZPB1
+		asl  a
+		rol  c64.SCRATCH_ZPB1
+		asl  a
+		rol  c64.SCRATCH_ZPB1
+
+		sta  c64.ESTACK_LO+1,x
+		lda  c64.SCRATCH_ZPB1
+		sta  c64.ESTACK_HI+1,x
+		rts
+		.pend
+
+shift_left_w_6	.proc
+		lda  c64.ESTACK_HI+1,x
+		sta  c64.SCRATCH_ZPB1
+		lda  c64.ESTACK_LO+1,x
+		jmp  shift_left_w_7._shift6
+		.pend
+
+shift_left_w_5	.proc
+		lda  c64.ESTACK_HI+1,x
+		sta  c64.SCRATCH_ZPB1
+		lda  c64.ESTACK_LO+1,x
+		jmp  shift_left_w_7._shift5
+		.pend
+
+shift_left_w_4	.proc
+		lda  c64.ESTACK_HI+1,x
+		sta  c64.SCRATCH_ZPB1
+		lda  c64.ESTACK_LO+1,x
+		jmp  shift_left_w_7._shift4
+		.pend
+
+shift_left_w_3	.proc
+		lda  c64.ESTACK_HI+1,x
+		sta  c64.SCRATCH_ZPB1
+		lda  c64.ESTACK_LO+1,x
+		jmp  shift_left_w_7._shift3
+		.pend
+
+shift_right_uw_7	.proc
+		lda  c64.ESTACK_LO+1,x
+		sta  c64.SCRATCH_ZPB1
+		lda  c64.ESTACK_HI+1,x
+
+		lsr  a
+		ror  c64.SCRATCH_ZPB1
+_shift6		lsr  a
+		ror  c64.SCRATCH_ZPB1
+_shift5		lsr  a
+		ror  c64.SCRATCH_ZPB1
+_shift4		lsr  a
+		ror  c64.SCRATCH_ZPB1
+_shift3		lsr  a
+		ror  c64.SCRATCH_ZPB1
+		lsr  a
+		ror  c64.SCRATCH_ZPB1
+		lsr  a
+		ror  c64.SCRATCH_ZPB1
+
+		sta  c64.ESTACK_HI+1,x
+		lda  c64.SCRATCH_ZPB1
+		sta  c64.ESTACK_LO+1,x
+		rts
+		.pend
+
+shift_right_uw_6	.proc
+		lda  c64.ESTACK_LO+1,x
+		sta  c64.SCRATCH_ZPB1
+		lda  c64.ESTACK_HI+1,x
+		jmp  shift_right_uw_7._shift6
+		.pend
+
+shift_right_uw_5	.proc
+		lda  c64.ESTACK_LO+1,x
+		sta  c64.SCRATCH_ZPB1
+		lda  c64.ESTACK_HI+1,x
+		jmp  shift_right_uw_7._shift5
+		.pend
+
+shift_right_uw_4	.proc
+		lda  c64.ESTACK_LO+1,x
+		sta  c64.SCRATCH_ZPB1
+		lda  c64.ESTACK_HI+1,x
+		jmp  shift_right_uw_7._shift4
+		.pend
+
+shift_right_uw_3	.proc
+		lda  c64.ESTACK_LO+1,x
+		sta  c64.SCRATCH_ZPB1
+		lda  c64.ESTACK_HI+1,x
+		jmp  shift_right_uw_7._shift3
+		.pend
+
+
+shift_right_w_7		.proc
+		lda  c64.ESTACK_LO+1,x
+		sta  c64.SCRATCH_ZPWORD1
+		lda  c64.ESTACK_HI+1,x
+		sta  c64.SCRATCH_ZPWORD1+1
+
+		asl  a
+		ror  c64.SCRATCH_ZPWORD1+1
+		ror  c64.SCRATCH_ZPWORD1
+
+		lda  c64.SCRATCH_ZPWORD1+1
+_shift6		asl  a
+		ror  c64.SCRATCH_ZPWORD1+1
+		ror  c64.SCRATCH_ZPWORD1
+		lda  c64.SCRATCH_ZPWORD1+1
+_shift5		asl  a
+		ror  c64.SCRATCH_ZPWORD1+1
+		ror  c64.SCRATCH_ZPWORD1
+		lda  c64.SCRATCH_ZPWORD1+1
+_shift4		asl  a
+		ror  c64.SCRATCH_ZPWORD1+1
+		ror  c64.SCRATCH_ZPWORD1
+		lda  c64.SCRATCH_ZPWORD1+1
+_shift3		asl  a
+		ror  c64.SCRATCH_ZPWORD1+1
+		ror  c64.SCRATCH_ZPWORD1
+		lda  c64.SCRATCH_ZPWORD1+1
+		asl  a
+		ror  c64.SCRATCH_ZPWORD1+1
+		ror  c64.SCRATCH_ZPWORD1
+		lda  c64.SCRATCH_ZPWORD1+1
+		asl  a
+		ror  c64.SCRATCH_ZPWORD1+1
+		ror  c64.SCRATCH_ZPWORD1
+
+		lda  c64.SCRATCH_ZPWORD1
+		sta  c64.ESTACK_LO+1,x
+		lda  c64.SCRATCH_ZPWORD1+1
+		sta  c64.ESTACK_HI+1,x
+		rts
+		.pend
+
+shift_right_w_6	.proc
+		lda  c64.ESTACK_LO+1,x
+		sta  c64.SCRATCH_ZPWORD1
+		lda  c64.ESTACK_HI+1,x
+		sta  c64.SCRATCH_ZPWORD1+1
+		jmp  shift_right_w_7._shift6
+		.pend
+
+shift_right_w_5	.proc
+		lda  c64.ESTACK_LO+1,x
+		sta  c64.SCRATCH_ZPWORD1
+		lda  c64.ESTACK_HI+1,x
+		sta  c64.SCRATCH_ZPWORD1+1
+		jmp  shift_right_w_7._shift5
+		.pend
+
+shift_right_w_4	.proc
+		lda  c64.ESTACK_LO+1,x
+		sta  c64.SCRATCH_ZPWORD1
+		lda  c64.ESTACK_HI+1,x
+		sta  c64.SCRATCH_ZPWORD1+1
+		jmp  shift_right_w_7._shift4
+		.pend
+
+shift_right_w_3	.proc
+		lda  c64.ESTACK_LO+1,x
+		sta  c64.SCRATCH_ZPWORD1
+		lda  c64.ESTACK_HI+1,x
+		sta  c64.SCRATCH_ZPWORD1+1
+		jmp  shift_right_w_7._shift3
+		.pend
+

compiler/res/prog8lib/prog8lib.asm

@@ -35,7 +35,7 @@ init_system	.proc
 		rts
 		.pend
 
-		
+
 read_byte_from_address	.proc
 	; -- read the byte from the memory address on the top of the stack, return in A (stack remains unchanged)
 		lda  c64.ESTACK_LO+1,x
@@ -45,7 +45,7 @@ read_byte_from_address	.proc
 +		lda  $ffff		; modified
 		rts
 		.pend
-		
+
 
 add_a_to_zpword	.proc
 	; -- add ubyte in A to the uword in c64.SCRATCH_ZPWORD1
@@ -651,6 +651,18 @@ greatereq_w	.proc
 		bmi  equal_b._equal_b_false
 		.pend
 
+
+orig_stackpointer	.byte  0	; stores the Stack pointer register at program start
+
+func_exit	.proc
+		; -- immediately exit the program with a return code in the A register
+		lda  c64.ESTACK_LO+1,x
+		ldx  orig_stackpointer
+		txs
+		rts		; return to original caller
+		.pend
+
+
 func_read_flags	.proc
 		; -- put the processor status register on the stack
 		php
@@ -716,7 +728,7 @@ func_sin8	.proc
 		lda  _sinecos8,y
 		sta  c64.ESTACK_LO+1,x
 		rts
-_sinecos8	.char  127 * sin(range(256+64) * rad(360.0/256.0))
+_sinecos8	.char  trunc(127.0 * sin(range(256+64) * rad(360.0/256.0)))
 		.pend
 
 func_sin8u	.proc
@@ -724,7 +736,7 @@ func_sin8u	.proc
 		lda  _sinecos8u,y
 		sta  c64.ESTACK_LO+1,x
 		rts
-_sinecos8u	.byte  128 + 127.5 * sin(range(256+64) * rad(360.0/256.0))
+_sinecos8u	.byte  trunc(128.0 + 127.5 * sin(range(256+64) * rad(360.0/256.0)))
 		.pend
 
 func_sin16	.proc
@@ -735,7 +747,7 @@ func_sin16	.proc
 		sta  c64.ESTACK_HI+1,x
 		rts
 
-_  :=  32767 * sin(range(256+64) * rad(360.0/256.0))
+_  :=  trunc(32767.0 * sin(range(256+64) * rad(360.0/256.0)))
 _sinecos8lo     .byte  <_
 _sinecos8hi     .byte  >_
 		.pend
@@ -748,7 +760,7 @@ func_sin16u	.proc
 		sta  c64.ESTACK_HI+1,x
 		rts
 
-_  :=  32768 + 32767.5 * sin(range(256+64) * rad(360.0/256.0))
+_  :=  trunc(32768.0 + 32767.5 * sin(range(256+64) * rad(360.0/256.0)))
 _sinecos8ulo     .byte  <_
 _sinecos8uhi     .byte  >_
 		.pend
@@ -851,11 +863,12 @@ func_all_w	.proc
 		bne  +
 		iny
 		lda  (c64.SCRATCH_ZPWORD1),y
-		bne  +
+		bne  ++
 		lda  #0
 		sta  c64.ESTACK_LO+1,x
 		rts
 +		iny
++		iny
 _cmp_mod	cpy  #255		; modified
 		bne  -
 		lda  #1
@@ -1383,3 +1396,809 @@ _mod2b          lda  #0                         ; self-modified
 _done		rts
 		.pend
 
+
+sort_ub		.proc
+		; 8bit unsigned sort
+		; sorting subroutine coded by mats rosengren (mats.rosengren@esa.int)
+		; input:  address of array to sort in c64.SCRATCH_ZPWORD1, length in c64.SCRATCH_ZPB1
+		; first, put pointer BEFORE array
+		lda  c64.SCRATCH_ZPWORD1
+		bne  +
+		dec  c64.SCRATCH_ZPWORD1+1
++		dec  c64.SCRATCH_ZPWORD1
+_sortloop	ldy  c64.SCRATCH_ZPB1		;start of subroutine sort
+		lda  (c64.SCRATCH_ZPWORD1),y	;last value in (what is left of) sequence to be sorted
+		sta  c64.SCRATCH_ZPREG		;save value. will be over-written by largest number
+		jmp  _l2
+_l1		dey
+		beq  _l3
+		lda  (c64.SCRATCH_ZPWORD1),y
+		cmp  c64.SCRATCH_ZPWORD2+1
+		bcc  _l1
+_l2		sty  c64.SCRATCH_ZPWORD2	;index of potentially largest value
+		sta  c64.SCRATCH_ZPWORD2+1	;potentially largest value
+		jmp  _l1
+_l3		ldy  c64.SCRATCH_ZPB1		;where the largest value shall be put
+		lda  c64.SCRATCH_ZPWORD2+1	;the largest value
+		sta  (c64.SCRATCH_ZPWORD1),y	;put largest value in place
+		ldy  c64.SCRATCH_ZPWORD2	;index of free space
+		lda  c64.SCRATCH_ZPREG		;the over-written value
+		sta  (c64.SCRATCH_ZPWORD1),y	;put the over-written value in the free space
+		dec  c64.SCRATCH_ZPB1		;end of the shorter sequence still left
+		bne  _sortloop			;start working with the shorter sequence
+		rts
+		.pend
+
+
+sort_b		.proc
+		; 8bit signed sort
+		; sorting subroutine coded by mats rosengren (mats.rosengren@esa.int)
+		; input:  address of array to sort in c64.SCRATCH_ZPWORD1, length in c64.SCRATCH_ZPB1
+		; first, put pointer BEFORE array
+		lda  c64.SCRATCH_ZPWORD1
+		bne  +
+		dec  c64.SCRATCH_ZPWORD1+1
++		dec  c64.SCRATCH_ZPWORD1
+_sortloop	ldy  c64.SCRATCH_ZPB1		;start of subroutine sort
+		lda  (c64.SCRATCH_ZPWORD1),y	;last value in (what is left of) sequence to be sorted
+		sta  c64.SCRATCH_ZPREG		;save value. will be over-written by largest number
+		jmp  _l2
+_l1		dey
+		beq  _l3
+		lda  (c64.SCRATCH_ZPWORD1),y
+		cmp  c64.SCRATCH_ZPWORD2+1
+		bmi  _l1
+_l2		sty  c64.SCRATCH_ZPWORD2	;index of potentially largest value
+		sta  c64.SCRATCH_ZPWORD2+1	;potentially largest value
+		jmp  _l1
+_l3		ldy  c64.SCRATCH_ZPB1		;where the largest value shall be put
+		lda  c64.SCRATCH_ZPWORD2+1	;the largest value
+		sta  (c64.SCRATCH_ZPWORD1),y	;put largest value in place
+		ldy  c64.SCRATCH_ZPWORD2	;index of free space
+		lda  c64.SCRATCH_ZPREG		;the over-written value
+		sta  (c64.SCRATCH_ZPWORD1),y	;put the over-written value in the free space
+		dec  c64.SCRATCH_ZPB1		;end of the shorter sequence still left
+		bne  _sortloop			;start working with the shorter sequence
+		rts
+		.pend
+
+
+sort_uw		.proc
+		; 16bit unsigned sort
+		; sorting subroutine coded by mats rosengren (mats.rosengren@esa.int)
+		; input:  address of array to sort in c64.SCRATCH_ZPWORD1, length in c64.SCRATCH_ZPB1
+		; first: subtract 2 of the pointer
+		asl  c64.SCRATCH_ZPB1		; *2 because words
+		lda  c64.SCRATCH_ZPWORD1
+		sec
+		sbc  #2
+		sta  c64.SCRATCH_ZPWORD1
+		bcs  _sort_loop
+		dec  c64.SCRATCH_ZPWORD1+1
+_sort_loop	ldy  c64.SCRATCH_ZPB1    	;start of subroutine sort
+		lda  (c64.SCRATCH_ZPWORD1),y    ;last value in (what is left of) sequence to be sorted
+		sta  _work3          		;save value. will be over-written by largest number
+		iny
+		lda  (c64.SCRATCH_ZPWORD1),y
+		sta  _work3+1
+		dey
+		jmp  _l2
+_l1		dey
+		dey
+		beq  _l3
+		iny
+		lda  (c64.SCRATCH_ZPWORD1),y
+		dey
+		cmp  c64.SCRATCH_ZPWORD2+1
+		bne  +
+		lda  (c64.SCRATCH_ZPWORD1),y
+		cmp  c64.SCRATCH_ZPWORD2
++		bcc  _l1
+_l2		sty  _work1          		;index of potentially largest value
+		lda  (c64.SCRATCH_ZPWORD1),y
+		sta  c64.SCRATCH_ZPWORD2          ;potentially largest value
+		iny
+		lda  (c64.SCRATCH_ZPWORD1),y
+		sta  c64.SCRATCH_ZPWORD2+1
+		dey
+		jmp  _l1
+_l3		ldy  c64.SCRATCH_ZPB1           ;where the largest value shall be put
+		lda  c64.SCRATCH_ZPWORD2          ;the largest value
+		sta  (c64.SCRATCH_ZPWORD1),y      ;put largest value in place
+		iny
+		lda  c64.SCRATCH_ZPWORD2+1
+		sta  (c64.SCRATCH_ZPWORD1),y
+		ldy  _work1         		 ;index of free space
+		lda  _work3          		;the over-written value
+		sta  (c64.SCRATCH_ZPWORD1),y      ;put the over-written value in the free space
+		iny
+		lda  _work3+1
+		sta  (c64.SCRATCH_ZPWORD1),y
+		dey
+		dec  c64.SCRATCH_ZPB1           ;end of the shorter sequence still left
+		dec  c64.SCRATCH_ZPB1
+		bne  _sort_loop           ;start working with the shorter sequence
+		rts
+_work1	.byte  0
+_work3	.word  0
+		.pend
+
+
+sort_w		.proc
+		; 16bit signed sort
+		; sorting subroutine coded by mats rosengren (mats.rosengren@esa.int)
+		; input:  address of array to sort in c64.SCRATCH_ZPWORD1, length in c64.SCRATCH_ZPB1
+		; first: subtract 2 of the pointer
+		asl  c64.SCRATCH_ZPB1		; *2 because words
+		lda  c64.SCRATCH_ZPWORD1
+		sec
+		sbc  #2
+		sta  c64.SCRATCH_ZPWORD1
+		bcs  _sort_loop
+		dec  c64.SCRATCH_ZPWORD1+1
+_sort_loop	ldy  c64.SCRATCH_ZPB1    	;start of subroutine sort
+		lda  (c64.SCRATCH_ZPWORD1),y    ;last value in (what is left of) sequence to be sorted
+		sta  _work3          		;save value. will be over-written by largest number
+		iny
+		lda  (c64.SCRATCH_ZPWORD1),y
+		sta  _work3+1
+		dey
+		jmp  _l2
+_l1		dey
+		dey
+		beq  _l3
+		lda  (c64.SCRATCH_ZPWORD1),y
+		cmp  c64.SCRATCH_ZPWORD2
+		iny
+		lda  (c64.SCRATCH_ZPWORD1),y
+		dey
+		sbc  c64.SCRATCH_ZPWORD2+1
+		bvc  +
+		eor  #$80
++		bmi  _l1
+_l2		sty  _work1          		;index of potentially largest value
+		lda  (c64.SCRATCH_ZPWORD1),y
+		sta  c64.SCRATCH_ZPWORD2          ;potentially largest value
+		iny
+		lda  (c64.SCRATCH_ZPWORD1),y
+		sta  c64.SCRATCH_ZPWORD2+1
+		dey
+		jmp  _l1
+_l3		ldy  c64.SCRATCH_ZPB1           ;where the largest value shall be put
+		lda  c64.SCRATCH_ZPWORD2          ;the largest value
+		sta  (c64.SCRATCH_ZPWORD1),y      ;put largest value in place
+		iny
+		lda  c64.SCRATCH_ZPWORD2+1
+		sta  (c64.SCRATCH_ZPWORD1),y
+		ldy  _work1         		 ;index of free space
+		lda  _work3          		;the over-written value
+		sta  (c64.SCRATCH_ZPWORD1),y      ;put the over-written value in the free space
+		iny
+		lda  _work3+1
+		sta  (c64.SCRATCH_ZPWORD1),y
+		dey
+		dec  c64.SCRATCH_ZPB1           ;end of the shorter sequence still left
+		dec  c64.SCRATCH_ZPB1
+		bne  _sort_loop           ;start working with the shorter sequence
+		rts
+_work1	.byte  0
+_work3	.word  0
+		.pend
+
+
+reverse_b	.proc
+		; --- reverse an array of bytes (in-place)
+		; inputs:  pointer to array in c64.SCRATCH_ZPWORD1, length in A
+_index_right = c64.SCRATCH_ZPWORD2
+_index_left = c64.SCRATCH_ZPWORD2+1
+_loop_count = c64.SCRATCH_ZPREG
+		sta  _loop_count
+		lsr  _loop_count
+		sec
+		sbc  #1
+		sta  _index_right
+		lda  #0
+		sta  _index_left
+_loop		ldy  _index_right
+		lda  (c64.SCRATCH_ZPWORD1),y
+		pha
+		ldy  _index_left
+		lda  (c64.SCRATCH_ZPWORD1),y
+		ldy  _index_right
+		sta  (c64.SCRATCH_ZPWORD1),y
+		pla
+		ldy  _index_left
+		sta  (c64.SCRATCH_ZPWORD1),y
+		inc  _index_left
+		dec  _index_right
+		dec  _loop_count
+		bne  _loop
+		rts
+		.pend
+
+
+reverse_f	.proc
+		; --- reverse an array of floats
+_left_index = c64.SCRATCH_ZPWORD2
+_right_index = c64.SCRATCH_ZPWORD2+1
+_loop_count = c64.SCRATCH_ZPREG
+		pha
+		sta  c64.SCRATCH_ZPREG
+		asl  a
+		asl  a
+		clc
+		adc  c64.SCRATCH_ZPREG		; *5 because float
+		sec
+		sbc  #5
+		sta  _right_index
+		lda  #0
+		sta  _left_index
+		pla
+		lsr  a
+		sta  _loop_count
+_loop		; push the left indexed float on the stack
+		ldy  _left_index
+		lda  (c64.SCRATCH_ZPWORD1),y
+		pha
+		iny
+		lda  (c64.SCRATCH_ZPWORD1),y
+		pha
+		iny
+		lda  (c64.SCRATCH_ZPWORD1),y
+		pha
+		iny
+		lda  (c64.SCRATCH_ZPWORD1),y
+		pha
+		iny
+		lda  (c64.SCRATCH_ZPWORD1),y
+		pha
+		; copy right index float to left index float
+		ldy  _right_index
+		lda  (c64.SCRATCH_ZPWORD1),y
+		ldy  _left_index
+		sta  (c64.SCRATCH_ZPWORD1),y
+		inc  _left_index
+		inc  _right_index
+		ldy  _right_index
+		lda  (c64.SCRATCH_ZPWORD1),y
+		ldy  _left_index
+		sta  (c64.SCRATCH_ZPWORD1),y
+		inc  _left_index
+		inc  _right_index
+		ldy  _right_index
+		lda  (c64.SCRATCH_ZPWORD1),y
+		ldy  _left_index
+		sta  (c64.SCRATCH_ZPWORD1),y
+		inc  _left_index
+		inc  _right_index
+		ldy  _right_index
+		lda  (c64.SCRATCH_ZPWORD1),y
+		ldy  _left_index
+		sta  (c64.SCRATCH_ZPWORD1),y
+		inc  _left_index
+		inc  _right_index
+		ldy  _right_index
+		lda  (c64.SCRATCH_ZPWORD1),y
+		ldy  _left_index
+		sta  (c64.SCRATCH_ZPWORD1),y
+		; pop the float off the stack into the right index float
+		ldy  _right_index
+		pla
+		sta  (c64.SCRATCH_ZPWORD1),y
+		dey
+		pla
+		sta  (c64.SCRATCH_ZPWORD1),y
+		dey
+		pla
+		sta  (c64.SCRATCH_ZPWORD1),y
+		dey
+		pla
+		sta  (c64.SCRATCH_ZPWORD1),y
+		dey
+		pla
+		sta  (c64.SCRATCH_ZPWORD1),y
+		inc  _left_index
+		lda  _right_index
+		sec
+		sbc  #9
+		sta  _right_index
+		dec  _loop_count
+		bne  _loop
+		rts
+
+		.pend
+
+
+reverse_w	.proc
+		; --- reverse an array of words (in-place)
+		; inputs:  pointer to array in c64.SCRATCH_ZPWORD1, length in A
+_index_first = c64.SCRATCH_ZPWORD2
+_index_second = c64.SCRATCH_ZPWORD2+1
+_loop_count = c64.SCRATCH_ZPREG
+		pha
+		asl  a     ; *2 because words
+		sec
+		sbc  #2
+		sta  _index_first
+		lda  #0
+		sta  _index_second
+		pla
+		lsr  a
+		pha
+		sta  _loop_count
+		; first reverse the lsbs
+_loop_lo	ldy  _index_first
+		lda  (c64.SCRATCH_ZPWORD1),y
+		pha
+		ldy  _index_second
+		lda  (c64.SCRATCH_ZPWORD1),y
+		ldy  _index_first
+		sta  (c64.SCRATCH_ZPWORD1),y
+		pla
+		ldy  _index_second
+		sta  (c64.SCRATCH_ZPWORD1),y
+		inc  _index_second
+		inc  _index_second
+		dec  _index_first
+		dec  _index_first
+		dec  _loop_count
+		bne  _loop_lo
+		; now reverse the msbs
+		dec  _index_second
+		inc  _index_first
+		inc  _index_first
+		inc  _index_first
+		pla
+		sta  _loop_count
+_loop_hi	ldy  _index_first
+		lda  (c64.SCRATCH_ZPWORD1),y
+		pha
+		ldy  _index_second
+		lda  (c64.SCRATCH_ZPWORD1),y
+		ldy  _index_first
+		sta  (c64.SCRATCH_ZPWORD1),y
+		pla
+		ldy  _index_second
+		sta  (c64.SCRATCH_ZPWORD1),y
+		dec  _index_second
+		dec  _index_second
+		inc  _index_first
+		inc  _index_first
+		dec  _loop_count
+		bne  _loop_hi
+
+		rts
+		.pend
+
+ror2_mem_ub	.proc
+		; -- in-place 8-bit ror of byte at memory location on stack
+		inx
+		lda  c64.ESTACK_LO,x
+		sta  c64.SCRATCH_ZPWORD1
+		lda  c64.ESTACK_HI,x
+		sta  c64.SCRATCH_ZPWORD1+1
+		ldy  #0
+		lda  (c64.SCRATCH_ZPWORD1),y
+		lsr  a
+		bcc  +
+		ora  #$80
++		sta  (c64.SCRATCH_ZPWORD1),y
+		rts
+		.pend
+
+rol2_mem_ub	.proc
+		; -- in-place 8-bit rol of byte at memory location on stack
+		inx
+		lda  c64.ESTACK_LO,x
+		sta  c64.SCRATCH_ZPWORD1
+		lda  c64.ESTACK_HI,x
+		sta  c64.SCRATCH_ZPWORD1+1
+		ldy  #0
+		lda  (c64.SCRATCH_ZPWORD1),y
+		cmp  #$80
+		rol  a
+		sta  (c64.SCRATCH_ZPWORD1),y
+		rts
+		.pend
+
+lsl_array_b	.proc
+		; -- lsl a (u)byte in an array (index and array address on stack)
+		inx
+		ldy  c64.ESTACK_LO,x
+		inx
+		lda  c64.ESTACK_LO,x
+		sta  c64.SCRATCH_ZPWORD1
+		lda  c64.ESTACK_HI,x
+		sta  c64.SCRATCH_ZPWORD1+1
+		lda  (c64.SCRATCH_ZPWORD1),y
+		asl  a
+		sta  (c64.SCRATCH_ZPWORD1),y
+		rts
+		.pend
+
+lsr_array_ub	.proc
+		; -- lsr a ubyte in an array (index and array address on stack)
+		inx
+		ldy  c64.ESTACK_LO,x
+		inx
+		lda  c64.ESTACK_LO,x
+		sta  c64.SCRATCH_ZPWORD1
+		lda  c64.ESTACK_HI,x
+		sta  c64.SCRATCH_ZPWORD1+1
+		lda  (c64.SCRATCH_ZPWORD1),y
+		lsr  a
+		sta  (c64.SCRATCH_ZPWORD1),y
+		rts
+		.pend
+
+lsr_array_b	.proc
+		; -- lsr a byte in an array (index and array address on stack)
+		inx
+		ldy  c64.ESTACK_LO,x
+		inx
+		lda  c64.ESTACK_LO,x
+		sta  c64.SCRATCH_ZPWORD1
+		lda  c64.ESTACK_HI,x
+		sta  c64.SCRATCH_ZPWORD1+1
+		lda  (c64.SCRATCH_ZPWORD1),y
+		asl  a
+		lda  (c64.SCRATCH_ZPWORD1),y
+		ror  a
+		sta  (c64.SCRATCH_ZPWORD1),y
+		rts
+		.pend
+
+lsl_array_w	.proc
+		; -- lsl a (u)word in an array (index and array address on stack)
+		inx
+		lda  c64.ESTACK_LO,x
+		asl  a
+		tay
+		inx
+		lda  c64.ESTACK_LO,x
+		sta  c64.SCRATCH_ZPWORD1
+		lda  c64.ESTACK_HI,x
+		sta  c64.SCRATCH_ZPWORD1+1
+		lda  (c64.SCRATCH_ZPWORD1),y
+		asl  a
+		sta  (c64.SCRATCH_ZPWORD1),y
+		iny
+		lda  (c64.SCRATCH_ZPWORD1),y
+		rol  a
+		sta  (c64.SCRATCH_ZPWORD1),y
+		rts
+		.pend
+
+lsr_array_uw	.proc
+		; -- lsr a uword in an array (index and array address on stack)
+		inx
+		lda  c64.ESTACK_LO,x
+		asl  a
+		tay
+		inx
+		lda  c64.ESTACK_LO,x
+		sta  c64.SCRATCH_ZPWORD1
+		lda  c64.ESTACK_HI,x
+		sta  c64.SCRATCH_ZPWORD1+1
+		iny
+		lda  (c64.SCRATCH_ZPWORD1),y
+		lsr  a
+		sta  (c64.SCRATCH_ZPWORD1),y
+		dey
+		lda  (c64.SCRATCH_ZPWORD1),y
+		ror  a
+		sta  (c64.SCRATCH_ZPWORD1),y
+		rts
+		.pend
+
+lsr_array_w	.proc
+		; -- lsr a uword in an array (index and array address on stack)
+		inx
+		lda  c64.ESTACK_LO,x
+		asl  a
+		tay
+		inx
+		lda  c64.ESTACK_LO,x
+		sta  c64.SCRATCH_ZPWORD1
+		lda  c64.ESTACK_HI,x
+		sta  c64.SCRATCH_ZPWORD1+1
+		iny
+		lda  (c64.SCRATCH_ZPWORD1),y
+		asl  a
+		lda  (c64.SCRATCH_ZPWORD1),y
+		ror  a
+		sta  (c64.SCRATCH_ZPWORD1),y
+		dey
+		lda  (c64.SCRATCH_ZPWORD1),y
+		ror  a
+		sta  (c64.SCRATCH_ZPWORD1),y
+		rts
+		.pend
+
+rol_array_ub	.proc
+		; -- rol a ubyte in an array (index and array address on stack)
+		inx
+		ldy  c64.ESTACK_LO,x
+		inx
+		lda  c64.ESTACK_LO,x
+		sta  c64.SCRATCH_ZPWORD1
+		lda  c64.ESTACK_HI,x
+		sta  c64.SCRATCH_ZPWORD1+1
+		lda  (c64.SCRATCH_ZPWORD1),y
+		rol  a
+		sta  (c64.SCRATCH_ZPWORD1),y
+		rts
+		.pend
+
+
+ror_array_ub	.proc
+		; -- ror a ubyte in an array (index and array address on stack)
+		inx
+		ldy  c64.ESTACK_LO,x
+		inx
+		lda  c64.ESTACK_LO,x
+		sta  c64.SCRATCH_ZPWORD1
+		lda  c64.ESTACK_HI,x
+		sta  c64.SCRATCH_ZPWORD1+1
+		lda  (c64.SCRATCH_ZPWORD1),y
+		ror  a
+		sta  (c64.SCRATCH_ZPWORD1),y
+		rts
+		.pend
+
+ror2_array_ub	.proc
+		; -- ror2 (8-bit ror) a ubyte in an array (index and array address on stack)
+		inx
+		ldy  c64.ESTACK_LO,x
+		inx
+		lda  c64.ESTACK_LO,x
+		sta  c64.SCRATCH_ZPWORD1
+		lda  c64.ESTACK_HI,x
+		sta  c64.SCRATCH_ZPWORD1+1
+		lda  (c64.SCRATCH_ZPWORD1),y
+		lsr  a
+		bcc  +
+		ora  #$80
++		sta  (c64.SCRATCH_ZPWORD1),y
+		rts
+		.pend
+
+rol2_array_ub	.proc
+		; -- rol2 (8-bit rol) a ubyte in an array (index and array address on stack)
+		inx
+		ldy  c64.ESTACK_LO,x
+		inx
+		lda  c64.ESTACK_LO,x
+		sta  c64.SCRATCH_ZPWORD1
+		lda  c64.ESTACK_HI,x
+		sta  c64.SCRATCH_ZPWORD1+1
+		lda  (c64.SCRATCH_ZPWORD1),y
+		cmp  #$80
+		rol  a
+		sta  (c64.SCRATCH_ZPWORD1),y
+		rts
+		.pend
+
+ror_array_uw	.proc
+		; -- ror a uword in an array (index and array address on stack)
+		php
+		inx
+		lda  c64.ESTACK_LO,x
+		asl  a
+		tay
+		inx
+		lda  c64.ESTACK_LO,x
+		sta  c64.SCRATCH_ZPWORD1
+		lda  c64.ESTACK_HI,x
+		sta  c64.SCRATCH_ZPWORD1+1
+		iny
+		lda  (c64.SCRATCH_ZPWORD1),y
+		plp
+		ror  a
+		sta  (c64.SCRATCH_ZPWORD1),y
+		dey
+		lda  (c64.SCRATCH_ZPWORD1),y
+		ror  a
+		sta  (c64.SCRATCH_ZPWORD1),y
+		rts
+		.pend
+
+rol_array_uw	.proc
+		; -- rol a uword in an array (index and array address on stack)
+		php
+		inx
+		lda  c64.ESTACK_LO,x
+		asl  a
+		tay
+		inx
+		lda  c64.ESTACK_LO,x
+		sta  c64.SCRATCH_ZPWORD1
+		lda  c64.ESTACK_HI,x
+		sta  c64.SCRATCH_ZPWORD1+1
+		lda  (c64.SCRATCH_ZPWORD1),y
+		plp
+		rol  a
+		sta  (c64.SCRATCH_ZPWORD1),y
+		iny
+		lda  (c64.SCRATCH_ZPWORD1),y
+		rol  a
+		sta  (c64.SCRATCH_ZPWORD1),y
+		rts
+		.pend
+
+rol2_array_uw	.proc
+		; -- rol2 (16-bit rol) a uword in an array (index and array address on stack)
+		inx
+		lda  c64.ESTACK_LO,x
+		asl  a
+		tay
+		inx
+		lda  c64.ESTACK_LO,x
+		sta  c64.SCRATCH_ZPWORD1
+		lda  c64.ESTACK_HI,x
+		sta  c64.SCRATCH_ZPWORD1+1
+		lda  (c64.SCRATCH_ZPWORD1),y
+		asl  a
+		sta  (c64.SCRATCH_ZPWORD1),y
+		iny
+		lda  (c64.SCRATCH_ZPWORD1),y
+		rol  a
+		sta  (c64.SCRATCH_ZPWORD1),y
+		bcc  +
+		dey
+		lda  (c64.SCRATCH_ZPWORD1),y
+		adc  #0
+		sta  (c64.SCRATCH_ZPWORD1),y
++		rts
+		.pend
+
+ror2_array_uw	.proc
+		; -- ror2 (16-bit ror) a uword in an array (index and array address on stack)
+		inx
+		lda  c64.ESTACK_LO,x
+		asl  a
+		tay
+		inx
+		lda  c64.ESTACK_LO,x
+		sta  c64.SCRATCH_ZPWORD1
+		lda  c64.ESTACK_HI,x
+		sta  c64.SCRATCH_ZPWORD1+1
+		iny
+		lda  (c64.SCRATCH_ZPWORD1),y
+		lsr  a
+		sta  (c64.SCRATCH_ZPWORD1),y
+		dey
+		lda  (c64.SCRATCH_ZPWORD1),y
+		ror  a
+		sta  (c64.SCRATCH_ZPWORD1),y
+		bcc  +
+		iny
+		lda  (c64.SCRATCH_ZPWORD1),y
+		ora  #$80
+		sta  (c64.SCRATCH_ZPWORD1),y
++		rts
+		.pend
+
+		
+strcpy		.proc
+		; copy a string (0-terminated) from A/Y to (ZPWORD1)
+		; it is assumed the target string is large enough.
+		sta  c64.SCRATCH_ZPWORD2
+		sty  c64.SCRATCH_ZPWORD2+1
+		ldy  #$ff
+-		iny
+		lda  (c64.SCRATCH_ZPWORD2),y
+		sta  (c64.SCRATCH_ZPWORD1),y
+		bne  -
+		rts
+		.pend
+		
+		
+func_leftstr	.proc
+		; leftstr(source, target, length) with params on stack
+		inx
+		lda  c64.ESTACK_LO,x
+		tay			; length
+		inx
+		lda  c64.ESTACK_LO,x
+		sta  c64.SCRATCH_ZPWORD2
+		lda  c64.ESTACK_HI,x
+		sta  c64.SCRATCH_ZPWORD2+1
+		inx
+		lda  c64.ESTACK_LO,x
+		sta  c64.SCRATCH_ZPWORD1
+		lda  c64.ESTACK_HI,x
+		sta  c64.SCRATCH_ZPWORD1+1
+		lda  #0
+		sta  (c64.SCRATCH_ZPWORD2),y
+-		dey
+		cpy  #$ff
+		bne  +
+		rts
++		lda  (c64.SCRATCH_ZPWORD1),y
+		sta  (c64.SCRATCH_ZPWORD2),y
+		jmp  -
+		.pend
+
+func_rightstr	.proc
+		; rightstr(source, target, length) with params on stack
+		; make place for the 4 parameters for substr()
+		dex
+		dex
+		dex
+		dex
+		; X-> .
+		; x+1 -> length of segment
+		; x+2 -> start index
+		; X+3 -> target LO+HI
+		; X+4 -> source LO+HI
+		; original parameters:
+		;  x+5 -> original length LO
+		;  x+6 -> original targetLO + HI
+		;  x+7 -> original sourceLO + HI
+		; replicate paramters:
+		lda  c64.ESTACK_LO+5,x
+		sta  c64.ESTACK_LO+1,x
+		lda  c64.ESTACK_LO+6,x
+		sta  c64.ESTACK_LO+3,x
+		lda  c64.ESTACK_HI+6,x
+		sta  c64.ESTACK_HI+3,x
+		lda  c64.ESTACK_LO+7,x
+		sta  c64.ESTACK_LO+4,x
+		sta  c64.SCRATCH_ZPWORD1
+		lda  c64.ESTACK_HI+7,x
+		sta  c64.ESTACK_HI+4,x
+		sta  c64.SCRATCH_ZPWORD1+1
+		; determine string length
+		ldy  #0
+-		lda  (c64.SCRATCH_ZPWORD1),y
+		beq  +
+		iny
+		bne  -
++		tya
+		sec
+		sbc  c64.ESTACK_LO+1,x  ; start index = strlen - segment length
+		sta  c64.ESTACK_LO+2,x
+		jsr  func_substr
+		; unwind original params
+		inx
+		inx
+		inx
+		rts
+		.pend
+
+func_substr	.proc
+		; substr(source, target, start, length) with params on stack
+		inx
+		ldy  c64.ESTACK_LO,x	; length
+		inx
+		lda  c64.ESTACK_LO,x	; start
+		sta  c64.SCRATCH_ZPB1
+		inx
+		lda  c64.ESTACK_LO,x	
+		sta  c64.SCRATCH_ZPWORD2
+		lda  c64.ESTACK_HI,x
+		sta  c64.SCRATCH_ZPWORD2+1
+		inx
+		lda  c64.ESTACK_LO,x	
+		sta  c64.SCRATCH_ZPWORD1
+		lda  c64.ESTACK_HI,x
+		sta  c64.SCRATCH_ZPWORD1+1
+		; adjust src location
+		clc
+		lda  c64.SCRATCH_ZPWORD1
+		adc  c64.SCRATCH_ZPB1
+		sta  c64.SCRATCH_ZPWORD1
+		bcc  +
+		inc  c64.SCRATCH_ZPWORD1+1
++		lda  #0
+		sta  (c64.SCRATCH_ZPWORD2),y
+		jmp  _startloop
+-		lda  (c64.SCRATCH_ZPWORD1),y
+		sta  (c64.SCRATCH_ZPWORD2),y
+_startloop	dey
+		cpy  #$ff
+		bne  -
+		rts
+
+		.pend

compiler/res/version.txt

@@ -1 +1 @@
-1.50
+3.1

compiler/src/prog8/CompilerMain.kt

@@ -1,24 +1,25 @@
 package prog8
 
+import kotlinx.cli.*
 import prog8.ast.base.AstException
 import prog8.compiler.CompilationResult
 import prog8.compiler.compileProgram
+import prog8.compiler.target.CompilationTarget
+import prog8.compiler.target.c64.C64MachineDefinition
+import prog8.compiler.target.c64.Petscii
+import prog8.compiler.target.c64.codegen.AsmGen
 import prog8.parser.ParsingFailedError
-import prog8.vm.astvm.AstVm
+import java.io.IOException
 import java.nio.file.FileSystems
 import java.nio.file.Path
-import java.nio.file.Paths
 import java.nio.file.StandardWatchEventKinds
-import java.util.*
+import java.time.LocalDateTime
 import kotlin.system.exitProcess
 
 
 fun main(args: Array<String>) {
-
     printSoftwareHeader("compiler")
 
-    if (args.isEmpty())
-        usage()
     compileMain(args)
 }
 
@@ -29,58 +30,71 @@ internal fun printSoftwareHeader(what: String) {
 }
 
 
+fun pathFrom(stringPath: String, vararg rest: String): Path  = FileSystems.getDefault().getPath(stringPath, *rest)
+
+
 private fun compileMain(args: Array<String>) {
-    var emulatorToStart = ""
-    var moduleFile = ""
-    var writeAssembly = true
-    var optimize = true
-    var optimizeInlining = true
-    var launchAstVm = false
-    var watchMode = false
-    for (arg in args) {
-        if(arg=="-emu")
-            emulatorToStart = "x64"
-        else if(arg=="-emu2")
-            emulatorToStart = "x64sc"
-        else if(arg=="-noasm")
-            writeAssembly = false
-        else if(arg=="-noopt")
-            optimize = false
-        else if(arg=="-nooptinline")
-            optimizeInlining = false
-        else if(arg=="-avm")
-            launchAstVm = true
-        else if(arg=="-watch")
-            watchMode = true
-        else if(!arg.startsWith("-"))
-            moduleFile = arg
-        else
-            usage()
+    val cli = CommandLineInterface("prog8compiler")
+    val startEmulator by cli.flagArgument("-emu", "auto-start the Vice C-64 emulator after successful compilation")
+    val outputDir by cli.flagValueArgument("-out", "directory", "directory for output files instead of current directory", ".")
+    val dontWriteAssembly by cli.flagArgument("-noasm", "don't create assembly code")
+    val dontOptimize by cli.flagArgument("-noopt", "don't perform any optimizations")
+    val watchMode by cli.flagArgument("-watch", "continuous compilation mode (watches for file changes), greatly increases compilation speed")
+    val compilationTarget by cli.flagValueArgument("-target", "compilertarget", "target output of the compiler, currently only 'c64' (C64 6502 assembly) available", "c64")
+    val moduleFiles by cli.positionalArgumentsList("modules", "main module file(s) to compile", minArgs = 1)
+
+    try {
+        cli.parse(args)
+    } catch (e: Exception) {
+        exitProcess(1)
     }
 
-    if(watchMode) {
-        if(moduleFile.isBlank())
-            usage()
+    when(compilationTarget) {
+        "c64" -> {
+            with(CompilationTarget) {
+                name = "c64"
+                machine = C64MachineDefinition
+                encodeString = { str, altEncoding ->
+                    if(altEncoding) Petscii.encodeScreencode(str, true) else Petscii.encodePetscii(str, true)
+                }
+                decodeString = { bytes, altEncoding ->
+                    if(altEncoding) Petscii.decodeScreencode(bytes, true) else Petscii.decodePetscii(bytes, true)
+                }
+                asmGenerator = ::AsmGen
+            }
+        }
+        else -> {
+            System.err.println("invalid compilation target")
+            exitProcess(1)
+        }
+    }
 
+    val outputPath = pathFrom(outputDir)
+    if(!outputPath.toFile().isDirectory) {
+        System.err.println("Output path doesn't exist")
+        exitProcess(1)
+    }
+
+    if(watchMode && moduleFiles.size<=1) {
         val watchservice = FileSystems.getDefault().newWatchService()
 
         while(true) {
-            val filepath = Paths.get(moduleFile).normalize()
+            val filepath = pathFrom(moduleFiles.single()).normalize()
             println("Continuous watch mode active. Main module: $filepath")
 
             try {
-                val compilationResult = compileProgram(filepath, optimize, optimizeInlining, writeAssembly)
+                val compilationResult = compileProgram(filepath, !dontOptimize, !dontWriteAssembly, outputDir=outputPath)
                 println("Imported files (now watching:)")
                 for (importedFile in compilationResult.importedFiles) {
                     print("  ")
                     println(importedFile)
                     importedFile.parent.register(watchservice, StandardWatchEventKinds.ENTRY_MODIFY)
                 }
-                println("${Date()}: Waiting for file changes.")
+                println("[${LocalDateTime.now().withNano(0)}]  Waiting for file changes.")
                 val event = watchservice.take()
                 for(changed in event.pollEvents()) {
                     val changedPath = changed.context() as Path
-                    println("  change detected: ${changedPath}")
+                    println("  change detected: $changedPath")
                 }
                 event.reset()
                 println("\u001b[H\u001b[2J")      // clear the screen
@@ -90,52 +104,39 @@ private fun compileMain(args: Array<String>) {
         }
 
     } else {
-        if(moduleFile.isBlank())
-            usage()
-
-        val filepath = Paths.get(moduleFile).normalize()
-        val compilationResult: CompilationResult
-
-        try {
-            compilationResult = compileProgram(filepath, optimize, optimizeInlining, writeAssembly)
-            if(!compilationResult.success)
+        for(filepathRaw in moduleFiles) {
+            val filepath = pathFrom(filepathRaw).normalize()
+            val compilationResult: CompilationResult
+            try {
+                compilationResult = compileProgram(filepath, !dontOptimize, !dontWriteAssembly, outputDir=outputPath)
+                if(!compilationResult.success)
+                    exitProcess(1)
+            } catch (x: ParsingFailedError) {
                 exitProcess(1)
-        } catch (x: ParsingFailedError) {
-            exitProcess(1)
-        } catch (x: AstException) {
-            exitProcess(1)
-        }
+            } catch (x: AstException) {
+                exitProcess(1)
+            }
 
-        if (launchAstVm) {
-            println("\nLaunching AST-based vm...")
-            val vm = AstVm(compilationResult.programAst)
-            vm.run()
-        }
-
-        if (emulatorToStart.isNotEmpty()) {
-            if (compilationResult.programName.isEmpty())
-                println("\nCan't start emulator because no program was assembled.")
-            else {
-                println("\nStarting C-64 emulator $emulatorToStart...")
-                val cmdline = listOf(emulatorToStart, "-silent", "-moncommands", "${compilationResult.programName}.vice-mon-list",
-                        "-autostartprgmode", "1", "-autostart-warp", "-autostart", compilationResult.programName + ".prg")
-                val process = ProcessBuilder(cmdline).inheritIO().start()
-                process.waitFor()
+            if (startEmulator) {
+                if (compilationResult.programName.isEmpty())
+                    println("\nCan't start emulator because no program was assembled.")
+                else if(startEmulator) {
+                    for(emulator in listOf("x64sc", "x64")) {
+                        println("\nStarting C-64 emulator $emulator...")
+                        val cmdline = listOf(emulator, "-silent", "-moncommands", "${compilationResult.programName}.vice-mon-list",
+                                "-autostartprgmode", "1", "-autostart-warp", "-autostart", compilationResult.programName + ".prg")
+                        val processb = ProcessBuilder(cmdline).inheritIO()
+                        val process: Process
+                        try {
+                            process=processb.start()
+                        } catch(x: IOException) {
+                            continue  // try the next emulator executable
+                        }
+                        process.waitFor()
+                        break
+                    }
+                }
             }
         }
     }
 }
-
-
-private fun usage() {
-    System.err.println("Missing argument(s):")
-    System.err.println("    [-noasm]        don't create assembly code")
-    System.err.println("    [-noopt]        don't perform any optimizations")
-    System.err.println("    [-nooptinline]  don't perform subroutine inlining optimizations")
-    System.err.println("    [-emu]          auto-start the 'x64' C-64 emulator after successful compilation")
-    System.err.println("    [-emu2]         auto-start the 'x64sc' C-64 emulator after successful compilation")
-    System.err.println("    [-avm]          launch the prog8 ast-based virtual machine after compilation")
-    System.err.println("    [-watch]        continuous compilation mode (watches for file changes)")
-    System.err.println("    modulefile      main module file to compile")
-    exitProcess(1)
-}

compiler/src/prog8/ast/AstToSourceCode.kt

@@ -3,7 +3,6 @@ package prog8.ast
 import prog8.ast.antlr.escape
 import prog8.ast.base.DataType
 import prog8.ast.base.NumericDatatypes
-import prog8.ast.base.StringDatatypes
 import prog8.ast.base.VarDeclType
 import prog8.ast.expressions.*
 import prog8.ast.processing.IAstVisitor
@@ -79,7 +78,7 @@ class AstToSourceCode(val output: (text: String) -> Unit, val program: Program):
     private fun datatypeString(dt: DataType): String {
         return when(dt) {
             in NumericDatatypes -> dt.toString().toLowerCase()
-            in StringDatatypes -> dt.toString().toLowerCase()
+            DataType.STR -> dt.toString().toLowerCase()
             DataType.ARRAY_UB -> "ubyte["
             DataType.ARRAY_B -> "byte["
             DataType.ARRAY_UW -> "uword["
@@ -103,6 +102,12 @@ class AstToSourceCode(val output: (text: String) -> Unit, val program: Program):
     }
 
     override fun visit(decl: VarDecl) {
+
+        // if the vardecl is a parameter of a subroutine, don't output it again
+        val paramNames = (decl.definingScope() as? Subroutine)?.parameters?.map { it.name }
+        if(paramNames!=null && decl.name in paramNames)
+            return
+
         when(decl.type) {
             VarDeclType.VAR -> {}
             VarDeclType.CONST -> output("const ")
@@ -132,7 +137,7 @@ class AstToSourceCode(val output: (text: String) -> Unit, val program: Program):
             for(param in subroutine.parameters.zip(subroutine.asmParameterRegisters)) {
                 val reg =
                         when {
-                            true==param.second.stack -> "stack"
+                            param.second.stack -> "stack"
                             param.second.registerOrPair!=null -> param.second.registerOrPair.toString()
                             param.second.statusflag!=null -> param.second.statusflag.toString()
                             else -> "?????1"
@@ -178,8 +183,6 @@ class AstToSourceCode(val output: (text: String) -> Unit, val program: Program):
 
     private fun outputStatements(statements: List<Statement>) {
         for(stmt in statements) {
-            if(stmt is VarDecl && stmt.autogeneratedDontRemove)
-                continue    // skip autogenerated decls (to avoid generating a newline)
             outputi("")
             stmt.accept(this)
             output("\n")
@@ -197,9 +200,9 @@ class AstToSourceCode(val output: (text: String) -> Unit, val program: Program):
     private fun printout(call: IFunctionCall) {
         call.target.accept(this)
         output("(")
-        for(arg in call.arglist) {
+        for(arg in call.args) {
             arg.accept(this)
-            if(arg!==call.arglist.last())
+            if(arg!==call.args.last())
                 output(", ")
         }
         output(")")
@@ -256,15 +259,12 @@ class AstToSourceCode(val output: (text: String) -> Unit, val program: Program):
         output(numLiteral.number.toString())
     }
 
-    override fun visit(refLiteral: ReferenceLiteralValue) {
-        when {
-            refLiteral.isString -> output("\"${escape(refLiteral.str!!)}\"")
-            refLiteral.isArray -> {
-                if(refLiteral.array!=null) {
-                    outputListMembers(refLiteral.array.asSequence(), '[', ']')
-                }
-            }
-        }
+    override fun visit(string: StringLiteralValue) {
+        output("\"${escape(string.value)}\"")
+    }
+
+    override fun visit(array: ArrayLiteralValue) {
+        outputListMembers(array.value.asSequence(), '[', ']')
     }
 
     private fun outputListMembers(array: Sequence<Expression>, openchar: Char, closechar: Char) {
@@ -287,20 +287,17 @@ class AstToSourceCode(val output: (text: String) -> Unit, val program: Program):
     }
 
     override fun visit(assignment: Assignment) {
-        if(assignment is VariableInitializationAssignment) {
-            val targetVar = assignment.target.identifier?.targetVarDecl(program.namespace)
-            if(targetVar?.struct != null) {
-                // skip STRUCT init assignments
-                return
-            }
-        }
-
-        assignment.target.accept(this)
-        if (assignment.aug_op != null)
-            output(" ${assignment.aug_op} ")
-        else
+        val binExpr = assignment.value as? BinaryExpression
+        if(binExpr!=null && binExpr.left isSameAs assignment.target) {
+            // we only support the inplace assignments of the form A = A <operator> <value>
+            assignment.target.accept(this)
+            output(" ${binExpr.operator}= ")
+            binExpr.right.accept(this)
+        } else {
+            assignment.target.accept(this)
             output(" = ")
-        assignment.value.accept(this)
+            assignment.value.accept(this)
+        }
     }
 
     override fun visit(postIncrDecr: PostIncrDecr) {
@@ -308,27 +305,13 @@ class AstToSourceCode(val output: (text: String) -> Unit, val program: Program):
         output(postIncrDecr.operator)
     }
 
-    override fun visit(contStmt: Continue) {
-        output("continue")
-    }
-
     override fun visit(breakStmt: Break) {
         output("break")
     }
 
     override fun visit(forLoop: ForLoop) {
         output("for ")
-        if(forLoop.decltype!=null) {
-            output(datatypeString(forLoop.decltype))
-            if (forLoop.zeropage==ZeropageWish.REQUIRE_ZEROPAGE || forLoop.zeropage==ZeropageWish.PREFER_ZEROPAGE)
-                output(" @zp ")
-            else
-                output(" ")
-        }
-        if(forLoop.loopRegister!=null)
-            output(forLoop.loopRegister.toString())
-        else
-            forLoop.loopVar!!.accept(this)
+        forLoop.loopVar.accept(this)
         output(" in ")
         forLoop.iterable.accept(this)
         output(" ")
@@ -344,9 +327,16 @@ class AstToSourceCode(val output: (text: String) -> Unit, val program: Program):
 
     override fun visit(repeatLoop: RepeatLoop) {
         output("repeat ")
+        repeatLoop.iterations?.accept(this)
+        output(" ")
         repeatLoop.body.accept(this)
+    }
+
+    override fun visit(untilLoop: UntilLoop) {
+        output("do ")
+        untilLoop.body.accept(this)
         output(" until ")
-        repeatLoop.untilCondition.accept(this)
+        untilLoop.untilCondition.accept(this)
     }
 
     override fun visit(returnStmt: Return) {
@@ -362,12 +352,8 @@ class AstToSourceCode(val output: (text: String) -> Unit, val program: Program):
     }
 
     override fun visit(assignTarget: AssignTarget) {
-        if(assignTarget.register!=null)
-            output(assignTarget.register.toString())
-        else {
-            assignTarget.memoryAddress?.accept(this)
-            assignTarget.identifier?.accept(this)
-        }
+        assignTarget.memoryAddress?.accept(this)
+        assignTarget.identifier?.accept(this)
         assignTarget.arrayindexed?.accept(this)
     }
 
@@ -408,10 +394,6 @@ class AstToSourceCode(val output: (text: String) -> Unit, val program: Program):
         outputlni("}}")
     }
 
-    override fun visit(registerExpr: RegisterExpr) {
-        output(registerExpr.register.toString())
-    }
-
     override fun visit(builtinFunctionStatementPlaceholder: BuiltinFunctionStatementPlaceholder) {
         output(builtinFunctionStatementPlaceholder.name)
     }
@@ -446,10 +428,6 @@ class AstToSourceCode(val output: (text: String) -> Unit, val program: Program):
         outputln("")
     }
 
-    override fun visit(structLv: StructLiteralValue) {
-        outputListMembers(structLv.values.asSequence(), '{', '}')
-    }
-
     override fun visit(nopStatement: NopStatement) {
         output("; NOP @ ${nopStatement.position}  $nopStatement")
     }

compiler/src/prog8/ast/AstToplevel.kt

@@ -3,8 +3,9 @@ package prog8.ast
 import prog8.ast.base.*
 import prog8.ast.expressions.Expression
 import prog8.ast.expressions.IdentifierReference
+import prog8.ast.processing.AstWalker
+import prog8.ast.processing.IAstVisitor
 import prog8.ast.statements.*
-import prog8.compiler.HeapValues
 import prog8.functions.BuiltinFunctions
 import java.nio.file.Path
 
@@ -34,11 +35,13 @@ interface Node {
             return this
         throw FatalAstException("scope missing from $this")
     }
+
+    fun replaceChildNode(node: Node, replacement: Node)
 }
 
 interface IFunctionCall {
     var target: IdentifierReference
-    var arglist: MutableList<Expression>
+    var args: MutableList<Expression>
 }
 
 interface INameScope {
@@ -49,32 +52,31 @@ interface INameScope {
 
     fun linkParents(parent: Node)
 
-    fun subScopes(): Map<String, INameScope> {
-        val subscopes = mutableMapOf<String, INameScope>()
+    fun subScope(name: String): INameScope? {
         for(stmt in statements) {
             when(stmt) {
                 // NOTE: if other nodes are introduced that are a scope, or contain subscopes, they must be added here!
-                is ForLoop -> subscopes[stmt.body.name] = stmt.body
-                is RepeatLoop -> subscopes[stmt.body.name] = stmt.body
-                is WhileLoop -> subscopes[stmt.body.name] = stmt.body
+                is ForLoop -> if(stmt.body.name==name) return stmt.body
+                is UntilLoop -> if(stmt.body.name==name) return stmt.body
+                is WhileLoop -> if(stmt.body.name==name) return stmt.body
                 is BranchStatement -> {
-                    subscopes[stmt.truepart.name] = stmt.truepart
-                    if(stmt.elsepart.containsCodeOrVars())
-                        subscopes[stmt.elsepart.name] = stmt.elsepart
+                    if(stmt.truepart.name==name) return stmt.truepart
+                    if(stmt.elsepart.containsCodeOrVars() && stmt.elsepart.name==name) return stmt.elsepart
                 }
                 is IfStatement -> {
-                    subscopes[stmt.truepart.name] = stmt.truepart
-                    if(stmt.elsepart.containsCodeOrVars())
-                        subscopes[stmt.elsepart.name] = stmt.elsepart
+                    if(stmt.truepart.name==name) return stmt.truepart
+                    if(stmt.elsepart.containsCodeOrVars() && stmt.elsepart.name==name) return stmt.elsepart
                 }
                 is WhenStatement -> {
-                    stmt.choices.forEach { subscopes[it.statements.name] = it.statements }
+                    val scope = stmt.choices.firstOrNull { it.statements.name==name }
+                    if(scope!=null)
+                        return scope.statements
                 }
-                is INameScope -> subscopes[stmt.name] = stmt
+                is INameScope -> if(stmt.name==name) return stmt
                 else -> {}
             }
         }
-        return subscopes
+        return null
     }
 
     fun getLabelOrVariable(name: String): Statement? {
@@ -122,7 +124,7 @@ interface INameScope {
             for(module in localContext.definingModule().program.modules) {
                 var scope: INameScope? = module
                 for(name in scopedName.dropLast(1)) {
-                    scope = scope?.subScopes()?.get(name)
+                    scope = scope?.subScope(name)
                     if(scope==null)
                         break
                 }
@@ -130,7 +132,7 @@ interface INameScope {
                     val result = scope.getLabelOrVariable(scopedName.last())
                     if(result!=null)
                         return result
-                    return scope.subScopes()[scopedName.last()] as Statement?
+                    return scope.subScope(scopedName.last()) as Statement?
                 }
             }
             return null
@@ -142,7 +144,7 @@ interface INameScope {
                 val result = localScope.getLabelOrVariable(scopedName[0])
                 if (result != null)
                     return result
-                val subscope = localScope.subScopes()[scopedName[0]] as Statement?
+                val subscope = localScope.subScope(scopedName[0]) as Statement?
                 if (subscope != null)
                     return subscope
                 // not found in this scope, look one higher up
@@ -153,20 +155,57 @@ interface INameScope {
     }
 
     fun containsCodeOrVars() = statements.any { it !is Directive || it.directive == "%asminclude" || it.directive == "%asm"}
+    fun containsNoVars() = statements.all { it !is VarDecl }
     fun containsNoCodeNorVars() = !containsCodeOrVars()
 
     fun remove(stmt: Statement) {
         if(!statements.remove(stmt))
             throw FatalAstException("stmt to remove wasn't found in scope")
     }
+
+    fun getAllLabels(label: String): List<Label> {
+        val result = mutableListOf<Label>()
+
+        fun find(scope: INameScope) {
+            scope.statements.forEach {
+                when(it) {
+                    is Label -> result.add(it)
+                    is INameScope -> find(it)
+                    is IfStatement -> {
+                        find(it.truepart)
+                        find(it.elsepart)
+                    }
+                    is UntilLoop -> find(it.body)
+                    is RepeatLoop -> find(it.body)
+                    is WhileLoop -> find(it.body)
+                    is WhenStatement -> it.choices.forEach { choice->find(choice.statements) }
+                    else -> { /* do nothing */ }
+                }
+            }
+        }
+
+        find(this)
+        return result
+    }
+
+    fun nextSibling(stmt: Statement): Statement? {
+        val nextIdx = statements.indexOfFirst { it===stmt } + 1
+        return if(nextIdx < statements.size)
+            statements[nextIdx]
+        else
+            null
+    }
+}
+
+interface IAssignable {
+    // just a tag for now
 }
 
 
 /*********** Everything starts from here, the Program; zero or more modules *************/
 
-class Program(val name: String, val modules: MutableList<Module>) {
+class Program(val name: String, val modules: MutableList<Module>): Node {
     val namespace = GlobalNamespace(modules)
-    val heap = HeapValues()
 
     val definedLoadAddress: Int
         get() = modules.first().loadAddress
@@ -174,17 +213,35 @@ class Program(val name: String, val modules: MutableList<Module>) {
     var actualLoadAddress: Int = 0
 
     fun entrypoint(): Subroutine? {
-        val mainBlocks = modules.flatMap { it.statements }.filter { b -> b is Block && b.name=="main" }.map { it as Block }
+        val mainBlocks = allBlocks().filter { it.name=="main" }
         if(mainBlocks.size > 1)
             throw FatalAstException("more than one 'main' block")
         return if(mainBlocks.isEmpty()) {
             null
         } else {
-            mainBlocks[0].subScopes()["start"] as Subroutine?
+            mainBlocks[0].subScope("start") as Subroutine?
         }
     }
 
     fun allBlocks(): List<Block> = modules.flatMap { it.statements.filterIsInstance<Block>() }
+
+    override val position: Position = Position.DUMMY
+    override var parent: Node
+        get() = throw FatalAstException("program has no parent")
+        set(value) = throw FatalAstException("can't set parent of program")
+
+    override fun linkParents(parent: Node) {
+        modules.forEach {
+            it.linkParents(this)
+        }
+    }
+
+    override fun replaceChildNode(node: Node, replacement: Node) {
+        require(node is Module && replacement is Module)
+        val idx = modules.indexOfFirst { it===node }
+        modules[idx] = replacement
+        replacement.parent = this
+    }
 }
 
 class Module(override val name: String,
@@ -192,6 +249,7 @@ class Module(override val name: String,
              override val position: Position,
              val isLibraryModule: Boolean,
              val source: Path) : Node, INameScope {
+
     override lateinit var parent: Node
     lateinit var program: Program
     val importedBy = mutableListOf<Module>()
@@ -205,10 +263,20 @@ class Module(override val name: String,
     }
 
     override fun definingScope(): INameScope = program.namespace
+    override fun replaceChildNode(node: Node, replacement: Node) {
+        require(node is Statement && replacement is Statement)
+        val idx = statements.indexOfFirst { it===node }
+        statements[idx] = replacement
+        replacement.parent = this
+    }
 
     override fun toString() = "Module(name=$name, pos=$position, lib=$isLibraryModule)"
+
+    fun accept(visitor: IAstVisitor) = visitor.visit(this)
+    fun accept(visitor: AstWalker, parent: Node) = visitor.visit(this, parent)
 }
 
+
 class GlobalNamespace(val modules: List<Module>): Node, INameScope {
     override val name = "<<<global>>>"
     override val position = Position("<<<global>>>", 0, 0, 0)
@@ -219,6 +287,10 @@ class GlobalNamespace(val modules: List<Module>): Node, INameScope {
         modules.forEach { it.linkParents(this) }
     }
 
+    override fun replaceChildNode(node: Node, replacement: Node) {
+        throw FatalAstException("cannot replace anything in the namespace")
+    }
+
     override fun lookup(scopedName: List<String>, localContext: Node): Statement? {
         if (scopedName.size == 1 && scopedName[0] in BuiltinFunctions) {
             // builtin functions always exist, return a dummy localContext for them
@@ -240,12 +312,11 @@ class GlobalNamespace(val modules: List<Module>): Node, INameScope {
                 }
             }
         }
-
-        val stmt = localContext.definingModule().lookup(scopedName, localContext)
-        return when (stmt) {
+        // lookup something from the module.
+        return when (val stmt = localContext.definingModule().lookup(scopedName, localContext)) {
             is Label, is VarDecl, is Block, is Subroutine -> stmt
             null -> null
-            else -> throw NameError("wrong identifier target: $stmt", stmt.position)
+            else -> throw SyntaxError("wrong identifier target for $scopedName: $stmt", stmt.position)
         }
     }
 }

compiler/src/prog8/ast/antlr/Antr2Kotlin.kt

@@ -7,7 +7,7 @@ import prog8.ast.Module
 import prog8.ast.base.*
 import prog8.ast.expressions.*
 import prog8.ast.statements.*
-import prog8.compiler.target.c64.Petscii
+import prog8.compiler.target.CompilationTarget
 import prog8.parser.CustomLexer
 import prog8.parser.prog8Parser
 import java.io.CharConversionException
@@ -19,13 +19,13 @@ import java.nio.file.Path
 
 private data class NumericLiteral(val number: Number, val datatype: DataType)
 
-
-fun prog8Parser.ModuleContext.toAst(name: String, isLibrary: Boolean, source: Path) : Module {
+internal fun prog8Parser.ModuleContext.toAst(name: String, isLibrary: Boolean, source: Path) : Module {
     val nameWithoutSuffix = if(name.endsWith(".p8")) name.substringBeforeLast('.') else name
-    return Module(nameWithoutSuffix, modulestatement().asSequence().map { it.toAst(isLibrary) }.toMutableList(), toPosition(), isLibrary, source)
+    val directives = this.directive().map { it.toAst() }
+    val blocks = this.block().map { it.toAst(isLibrary) }
+    return Module(nameWithoutSuffix, (directives + blocks).toMutableList(), toPosition(), isLibrary, source)
 }
 
-
 private fun ParserRuleContext.toPosition() : Position {
     val customTokensource = this.start.tokenSource as? CustomLexer
     val filename =
@@ -38,27 +38,23 @@ private fun ParserRuleContext.toPosition() : Position {
     return Position(filename, start.line, start.charPositionInLine, stop.charPositionInLine + stop.text.length)
 }
 
-
-private fun prog8Parser.ModulestatementContext.toAst(isInLibrary: Boolean) : Statement {
-    val directive = directive()?.toAst()
-    if(directive!=null) return directive
-
-    val block = block()?.toAst(isInLibrary)
-    if(block!=null) return block
-
-    throw FatalAstException(text)
+private fun prog8Parser.BlockContext.toAst(isInLibrary: Boolean) : Statement {
+    val blockstatements = block_statement().map {
+        when {
+            it.variabledeclaration()!=null -> it.variabledeclaration().toAst()
+            it.subroutinedeclaration()!=null -> it.subroutinedeclaration().toAst()
+            it.directive()!=null -> it.directive().toAst()
+            it.inlineasm()!=null -> it.inlineasm().toAst()
+            else -> throw FatalAstException("weird block statement $it")
+        }
+    }
+    return Block(identifier().text, integerliteral()?.toAst()?.number?.toInt(), blockstatements.toMutableList(), isInLibrary, toPosition())
 }
 
-
-private fun prog8Parser.BlockContext.toAst(isInLibrary: Boolean) : Statement =
-        Block(identifier().text, integerliteral()?.toAst()?.number?.toInt(), statement_block().toAst(), isInLibrary, toPosition())
-
-
 private fun prog8Parser.Statement_blockContext.toAst(): MutableList<Statement> =
         statement().asSequence().map { it.toAst() }.toMutableList()
 
-
-private fun prog8Parser.StatementContext.toAst() : Statement {
+private fun prog8Parser.VariabledeclarationContext.toAst() : Statement {
     vardecl()?.let { return it.toAst() }
 
     varinitializer()?.let {
@@ -66,7 +62,7 @@ private fun prog8Parser.StatementContext.toAst() : Statement {
         return VarDecl(
                 VarDeclType.VAR,
                 vd.datatype()?.toAst() ?: DataType.STRUCT,
-                if(vd.ZEROPAGE() != null) ZeropageWish.PREFER_ZEROPAGE else ZeropageWish.DONTCARE,
+                if (vd.ZEROPAGE() != null) ZeropageWish.PREFER_ZEROPAGE else ZeropageWish.DONTCARE,
                 vd.arrayindex()?.toAst(),
                 vd.varname.text,
                 null,
@@ -114,7 +110,7 @@ private fun prog8Parser.StatementContext.toAst() : Statement {
         return VarDecl(
                 VarDeclType.CONST,
                 vd.datatype()?.toAst() ?: DataType.STRUCT,
-                if(vd.ZEROPAGE() != null) ZeropageWish.PREFER_ZEROPAGE else ZeropageWish.DONTCARE,
+                if (vd.ZEROPAGE() != null) ZeropageWish.PREFER_ZEROPAGE else ZeropageWish.DONTCARE,
                 vd.arrayindex()?.toAst(),
                 vd.varname.text,
                 null,
@@ -131,7 +127,7 @@ private fun prog8Parser.StatementContext.toAst() : Statement {
         return VarDecl(
                 VarDeclType.MEMORY,
                 vd.datatype()?.toAst() ?: DataType.STRUCT,
-                if(vd.ZEROPAGE() != null) ZeropageWish.PREFER_ZEROPAGE else ZeropageWish.DONTCARE,
+                if (vd.ZEROPAGE() != null) ZeropageWish.PREFER_ZEROPAGE else ZeropageWish.DONTCARE,
                 vd.arrayindex()?.toAst(),
                 vd.varname.text,
                 null,
@@ -142,15 +138,37 @@ private fun prog8Parser.StatementContext.toAst() : Statement {
         )
     }
 
+    structdecl()?.let {
+        return StructDecl(it.identifier().text,
+                it.vardecl().map { vd->vd.toAst() }.toMutableList(),
+                toPosition())
+    }
+
+    throw FatalAstException("weird variable decl $this")
+}
+
+private fun prog8Parser.SubroutinedeclarationContext.toAst() : Subroutine {
+    return when {
+        subroutine()!=null -> subroutine().toAst()
+        asmsubroutine()!=null -> asmsubroutine().toAst()
+        romsubroutine()!=null -> romsubroutine().toAst()
+        else -> throw FatalAstException("weird subroutine decl $this")
+    }
+}
+
+private fun prog8Parser.StatementContext.toAst() : Statement {
+    val vardecl = variabledeclaration()?.toAst()
+    if(vardecl!=null) return vardecl
+
     assignment()?.let {
-        return Assignment(it.assign_target().toAst(), null, it.expression().toAst(), it.toPosition())
+        return Assignment(it.assign_target().toAst(), it.expression().toAst(), it.toPosition())
     }
 
     augassignment()?.let {
-        return Assignment(it.assign_target().toAst(),
-                it.operator.text,
-                it.expression().toAst(),
-                it.toPosition())
+        // replace A += X  with  A = A + X
+        val target = it.assign_target().toAst()
+        val expression = BinaryExpression(target.toExpression(), it.operator.text.substring(0, 1), it.expression().toAst(), it.expression().toPosition())
+        return Assignment(it.assign_target().toAst(), expression, it.toPosition())
     }
 
     postincrdecr()?.let {
@@ -175,8 +193,8 @@ private fun prog8Parser.StatementContext.toAst() : Statement {
     val returnstmt = returnstmt()?.toAst()
     if(returnstmt!=null) return returnstmt
 
-    val sub = subroutine()?.toAst()
-    if(sub!=null) return sub
+    val subroutine = subroutinedeclaration()?.toAst()
+    if(subroutine!=null) return subroutine
 
     val asm = inlineasm()?.toAst()
     if(asm!=null) return asm
@@ -187,46 +205,57 @@ private fun prog8Parser.StatementContext.toAst() : Statement {
     val forloop = forloop()?.toAst()
     if(forloop!=null) return forloop
 
-    val repeatloop = repeatloop()?.toAst()
-    if(repeatloop!=null) return repeatloop
+    val untilloop = untilloop()?.toAst()
+    if(untilloop!=null) return untilloop
 
     val whileloop = whileloop()?.toAst()
     if(whileloop!=null) return whileloop
 
+    val repeatloop = repeatloop()?.toAst()
+    if(repeatloop!=null) return repeatloop
+
     val breakstmt = breakstmt()?.toAst()
     if(breakstmt!=null) return breakstmt
 
-    val continuestmt = continuestmt()?.toAst()
-    if(continuestmt!=null) return continuestmt
-
-    val asmsubstmt = asmsubroutine()?.toAst()
-    if(asmsubstmt!=null) return asmsubstmt
-
     val whenstmt = whenstmt()?.toAst()
     if(whenstmt!=null) return whenstmt
 
-    structdecl()?.let {
-        return StructDecl(it.identifier().text,
-                it.vardecl().map { vd->vd.toAst() }.toMutableList(),
-                toPosition())
-    }
-
     throw FatalAstException("unprocessed source text (are we missing ast conversion rules for parser elements?): $text")
 }
 
-private fun prog8Parser.AsmsubroutineContext.toAst(): Statement {
+private fun prog8Parser.AsmsubroutineContext.toAst(): Subroutine {
+    val subdecl = asmsub_decl().toAst()
+    val statements = statement_block()?.toAst() ?: mutableListOf()
+    return Subroutine(subdecl.name, subdecl.parameters, subdecl.returntypes,
+            subdecl.asmParameterRegisters, subdecl.asmReturnvaluesRegisters,
+            subdecl.asmClobbers, null, true, statements, toPosition())
+}
+
+private fun prog8Parser.RomsubroutineContext.toAst(): Subroutine {
+    val subdecl = asmsub_decl().toAst()
+    val address = integerliteral().toAst().number.toInt()
+    return Subroutine(subdecl.name, subdecl.parameters, subdecl.returntypes,
+            subdecl.asmParameterRegisters, subdecl.asmReturnvaluesRegisters,
+            subdecl.asmClobbers, address, true, mutableListOf(), toPosition())
+}
+
+private class AsmsubDecl(val name: String,
+                         val parameters: List<SubroutineParameter>,
+                         val returntypes: List<DataType>,
+                         val asmParameterRegisters: List<RegisterOrStatusflag>,
+                         val asmReturnvaluesRegisters: List<RegisterOrStatusflag>,
+                         val asmClobbers: Set<CpuRegister>)
+
+private fun prog8Parser.Asmsub_declContext.toAst(): AsmsubDecl {
     val name = identifier().text
-    val address = asmsub_address()?.address?.toAst()?.number?.toInt()
     val params = asmsub_params()?.toAst() ?: emptyList()
     val returns = asmsub_returns()?.toAst() ?: emptyList()
+    val clobbers = asmsub_clobbers()?.clobber()?.toAst() ?: emptySet()
     val normalParameters = params.map { SubroutineParameter(it.name, it.type, it.position) }
-    val normalReturnvalues = returns.map { it.type }
+    val normalReturntypes = returns.map { it.type }
     val paramRegisters = params.map { RegisterOrStatusflag(it.registerOrPair, it.statusflag, it.stack) }
     val returnRegisters = returns.map { RegisterOrStatusflag(it.registerOrPair, it.statusflag, it.stack) }
-    val clobbers = asmsub_clobbers()?.clobber()?.toAst() ?: emptySet()
-    val statements = statement_block()?.toAst() ?: mutableListOf()
-    return Subroutine(name, normalParameters, normalReturnvalues,
-            paramRegisters, returnRegisters, clobbers, address, true, statements, toPosition())
+    return AsmsubDecl(name, normalParameters, normalReturntypes, paramRegisters, returnRegisters, clobbers)
 }
 
 private class AsmSubroutineParameter(name: String,
@@ -242,36 +271,52 @@ private class AsmSubroutineReturn(val type: DataType,
                                   val stack: Boolean,
                                   val position: Position)
 
-private fun prog8Parser.ClobberContext.toAst(): Set<Register>
-        = this.register().asSequence().map { it.toAst() }.toSet()
-
-
 private fun prog8Parser.Asmsub_returnsContext.toAst(): List<AsmSubroutineReturn>
-        = asmsub_return().map { AsmSubroutineReturn(it.datatype().toAst(), it.registerorpair()?.toAst(), it.statusregister()?.toAst(), !it.stack?.text.isNullOrEmpty(), toPosition()) }
+        = asmsub_return().map {
+            val register = it.identifier()?.toAst()
+            var registerorpair: RegisterOrPair? = null
+            var statusregister: Statusflag? = null
+            if(register!=null) {
+                when (val name = register.nameInSource.single()) {
+                    in RegisterOrPair.names -> registerorpair = RegisterOrPair.valueOf(name)
+                    in Statusflag.names -> statusregister = Statusflag.valueOf(name)
+                    else -> throw FatalAstException("invalid register or status flag in $it")
+                }
+            }
+            AsmSubroutineReturn(
+                    it.datatype().toAst(),
+                    registerorpair,
+                    statusregister,
+                    !it.stack?.text.isNullOrEmpty(), toPosition())
+        }
 
 private fun prog8Parser.Asmsub_paramsContext.toAst(): List<AsmSubroutineParameter>
         = asmsub_param().map {
     val vardecl = it.vardecl()
     val datatype = vardecl.datatype()?.toAst() ?: DataType.STRUCT
-    AsmSubroutineParameter(vardecl.varname.text, datatype,
-            it.registerorpair()?.toAst(),
-            it.statusregister()?.toAst(),
+    val register = it.identifier()?.toAst()
+    var registerorpair: RegisterOrPair? = null
+    var statusregister: Statusflag? = null
+    if(register!=null) {
+        when (val name = register.nameInSource.single()) {
+            in RegisterOrPair.names -> registerorpair = RegisterOrPair.valueOf(name)
+            in Statusflag.names -> statusregister = Statusflag.valueOf(name)
+            else -> throw FatalAstException("invalid register or status flag in $it")
+        }
+    }
+    AsmSubroutineParameter(vardecl.varname.text, datatype, registerorpair, statusregister,
             !it.stack?.text.isNullOrEmpty(), toPosition())
 }
 
-
-private fun prog8Parser.StatusregisterContext.toAst() = Statusflag.valueOf(text)
-
-
 private fun prog8Parser.Functioncall_stmtContext.toAst(): Statement {
+    val void = this.VOID() != null
     val location = scoped_identifier().toAst()
     return if(expression_list() == null)
-        FunctionCallStatement(location, mutableListOf(), toPosition())
+        FunctionCallStatement(location, mutableListOf(), void, toPosition())
     else
-        FunctionCallStatement(location, expression_list().toAst().toMutableList(), toPosition())
+        FunctionCallStatement(location, expression_list().toAst().toMutableList(), void, toPosition())
 }
 
-
 private fun prog8Parser.FunctioncallContext.toAst(): FunctionCall {
     val location = scoped_identifier().toAst()
     return if(expression_list() == null)
@@ -280,11 +325,9 @@ private fun prog8Parser.FunctioncallContext.toAst(): FunctionCall {
         FunctionCall(location, expression_list().toAst().toMutableList(), toPosition())
 }
 
-
 private fun prog8Parser.InlineasmContext.toAst() =
         InlineAssembly(INLINEASMBLOCK().text, toPosition())
 
-
 private fun prog8Parser.ReturnstmtContext.toAst() : Return {
     return Return(expression()?.toAst(), toPosition())
 }
@@ -295,11 +338,9 @@ private fun prog8Parser.UnconditionaljumpContext.toAst(): Jump {
     return Jump(address, identifier, null, toPosition())
 }
 
-
 private fun prog8Parser.LabeldefContext.toAst(): Statement =
         Label(children[0].text, toPosition())
 
-
 private fun prog8Parser.SubroutineContext.toAst() : Subroutine {
     return Subroutine(identifier().text,
             sub_params()?.toAst() ?: emptyList(),
@@ -318,44 +359,42 @@ private fun prog8Parser.Sub_return_partContext.toAst(): List<DataType> {
     return returns.datatype().map { it.toAst() }
 }
 
-
 private fun prog8Parser.Sub_paramsContext.toAst(): List<SubroutineParameter> =
         vardecl().map {
             val datatype = it.datatype()?.toAst() ?: DataType.STRUCT
             SubroutineParameter(it.varname.text, datatype, it.toPosition())
         }
 
-
 private fun prog8Parser.Assign_targetContext.toAst() : AssignTarget {
-    val register = register()?.toAst()
     val identifier = scoped_identifier()
     return when {
-        register!=null -> AssignTarget(register, null, null, null, toPosition())
-        identifier!=null -> AssignTarget(null, identifier.toAst(), null, null, toPosition())
-        arrayindexed()!=null -> AssignTarget(null, null, arrayindexed().toAst(), null, toPosition())
-        directmemory()!=null -> AssignTarget(null, null, null, DirectMemoryWrite(directmemory().expression().toAst(), toPosition()), toPosition())
-        else -> AssignTarget(null, scoped_identifier()?.toAst(), null, null, toPosition())
+        identifier!=null -> AssignTarget(identifier.toAst(), null, null, toPosition())
+        arrayindexed()!=null -> AssignTarget(null, arrayindexed().toAst(), null, toPosition())
+        directmemory()!=null -> AssignTarget(null, null, DirectMemoryWrite(directmemory().expression().toAst(), toPosition()), toPosition())
+        else -> AssignTarget(scoped_identifier()?.toAst(), null, null, toPosition())
     }
 }
 
-private fun prog8Parser.RegisterContext.toAst() = Register.valueOf(text.toUpperCase())
+private fun prog8Parser.ClobberContext.toAst() : Set<CpuRegister> {
+    val names = this.identifier().map { it.toAst().nameInSource.single() }
+    return names.map { CpuRegister.valueOf(it) }.toSet()
+}
 
 private fun prog8Parser.DatatypeContext.toAst() = DataType.valueOf(text.toUpperCase())
 
-private fun prog8Parser.RegisterorpairContext.toAst() = RegisterOrPair.valueOf(text.toUpperCase())
-
-
 private fun prog8Parser.ArrayindexContext.toAst() : ArrayIndex =
         ArrayIndex(expression().toAst(), toPosition())
 
-
 private fun prog8Parser.DirectiveContext.toAst() : Directive =
         Directive(directivename.text, directivearg().map { it.toAst() }, toPosition())
 
+private fun prog8Parser.DirectiveargContext.toAst() : DirectiveArg {
+    val str = stringliteral()
+    if(str?.ALT_STRING_ENCODING() != null)
+        throw AstException("${toPosition()} can't use alternate string encodings for directive arguments")
 
-private fun prog8Parser.DirectiveargContext.toAst() : DirectiveArg =
-        DirectiveArg(stringliteral()?.text, identifier()?.text, integerliteral()?.toAst()?.number?.toInt(), toPosition())
-
+    return DirectiveArg(stringliteral()?.text, identifier()?.text, integerliteral()?.toAst()?.number?.toInt(), toPosition())
+}
 
 private fun prog8Parser.IntegerliteralContext.toAst(): NumericLiteral {
     fun makeLiteral(text: String, radix: Int, forceWord: Boolean): NumericLiteral {
@@ -408,7 +447,6 @@ private fun prog8Parser.IntegerliteralContext.toAst(): NumericLiteral {
     }
 }
 
-
 private fun prog8Parser.ExpressionContext.toAst() : Expression {
 
     val litval = literalvalue()
@@ -429,32 +467,28 @@ private fun prog8Parser.ExpressionContext.toAst() : Expression {
                     else -> throw FatalAstException("invalid datatype for numeric literal")
                 }
                 litval.floatliteral()!=null -> NumericLiteralValue(DataType.FLOAT, litval.floatliteral().toAst(), litval.toPosition())
-                litval.stringliteral()!=null -> ReferenceLiteralValue(DataType.STR, unescape(litval.stringliteral().text, litval.toPosition()), position = litval.toPosition())
+                litval.stringliteral()!=null -> litval.stringliteral().toAst()
                 litval.charliteral()!=null -> {
                     try {
-                        NumericLiteralValue(DataType.UBYTE, Petscii.encodePetscii(unescape(litval.charliteral().text, litval.toPosition()), true)[0], litval.toPosition())
+                        val cc=litval.charliteral()
+                        NumericLiteralValue(DataType.UBYTE, CompilationTarget.encodeString(
+                                unescape(litval.charliteral().SINGLECHAR().text, litval.toPosition()),
+                                litval.charliteral().ALT_STRING_ENCODING()!=null)[0], litval.toPosition())
                     } catch (ce: CharConversionException) {
                         throw SyntaxError(ce.message ?: ce.toString(), litval.toPosition())
                     }
                 }
                 litval.arrayliteral()!=null -> {
-                    val array = litval.arrayliteral()?.toAst()
+                    val array = litval.arrayliteral().toAst()
                     // the actual type of the arraysize can not yet be determined here (missing namespace & heap)
                     // the ConstantFold takes care of that and converts the type if needed.
-                    ReferenceLiteralValue(DataType.ARRAY_UB, array = array, position = litval.toPosition())
-                }
-                litval.structliteral()!=null -> {
-                    val values = litval.structliteral().expression().map { it.toAst() }
-                    StructLiteralValue(values, litval.toPosition())
+                    ArrayLiteralValue(InferredTypes.InferredType.unknown(), array, position = litval.toPosition())
                 }
                 else -> throw FatalAstException("invalid parsed literal")
             }
         }
     }
 
-    if(register()!=null)
-        return RegisterExpr(register().toAst(), register().toPosition())
-
     if(scoped_identifier()!=null)
         return scoped_identifier().toAst()
 
@@ -468,7 +502,8 @@ private fun prog8Parser.ExpressionContext.toAst() : Expression {
     if(funcall!=null) return funcall
 
     if (rangefrom!=null && rangeto!=null) {
-        val step = rangestep?.toAst() ?: NumericLiteralValue(DataType.UBYTE, 1, toPosition())
+        val defaultstep = if(rto.text == "to") 1 else -1
+        val step = rangestep?.toAst() ?: NumericLiteralValue(DataType.UBYTE, defaultstep, toPosition())
         return RangeExpr(rangefrom.toAst(), rangeto.toAst(), step, toPosition())
     }
 
@@ -490,6 +525,8 @@ private fun prog8Parser.ExpressionContext.toAst() : Expression {
     throw FatalAstException(text)
 }
 
+private fun prog8Parser.StringliteralContext.toAst(): StringLiteralValue =
+    StringLiteralValue(unescape(this.STRING().text, toPosition()), ALT_STRING_ENCODING()!=null, toPosition())
 
 private fun prog8Parser.ArrayindexedContext.toAst(): ArrayIndexedExpression {
     return ArrayIndexedExpression(scoped_identifier().toAst(),
@@ -497,28 +534,22 @@ private fun prog8Parser.ArrayindexedContext.toAst(): ArrayIndexedExpression {
             toPosition())
 }
 
-
 private fun prog8Parser.Expression_listContext.toAst() = expression().map{ it.toAst() }
 
-
 private fun prog8Parser.IdentifierContext.toAst() : IdentifierReference =
         IdentifierReference(listOf(text), toPosition())
 
-
 private fun prog8Parser.Scoped_identifierContext.toAst() : IdentifierReference =
         IdentifierReference(NAME().map { it.text }, toPosition())
 
-
 private fun prog8Parser.FloatliteralContext.toAst() = text.toDouble()
 
-
 private fun prog8Parser.BooleanliteralContext.toAst() = when(text) {
     "true" -> true
     "false" -> false
     else -> throw FatalAstException(text)
 }
 
-
 private fun prog8Parser.ArrayliteralContext.toAst() : Array<Expression> =
         expression().map { it.toAst() }.toTypedArray()
 
@@ -536,7 +567,6 @@ private fun prog8Parser.Else_partContext.toAst(): MutableList<Statement> {
     return statement_block()?.toAst() ?: mutableListOf(statement().toAst())
 }
 
-
 private fun prog8Parser.Branch_stmtContext.toAst(): BranchStatement {
     val branchcondition = branchcondition().toAst()
     val trueStatements = statement_block()?.toAst() ?: mutableListOf(statement().toAst())
@@ -549,27 +579,19 @@ private fun prog8Parser.Branch_stmtContext.toAst(): BranchStatement {
 
 private fun prog8Parser.BranchconditionContext.toAst() = BranchCondition.valueOf(text.substringAfter('_').toUpperCase())
 
-
 private fun prog8Parser.ForloopContext.toAst(): ForLoop {
-    val loopregister = register()?.toAst()
-    val datatype = datatype()?.toAst()
-    val zeropage = if(ZEROPAGE() != null) ZeropageWish.PREFER_ZEROPAGE else ZeropageWish.DONTCARE
-    val loopvar = identifier()?.toAst()
+    val loopvar = identifier().toAst()
     val iterable = expression()!!.toAst()
     val scope =
             if(statement()!=null)
                 AnonymousScope(mutableListOf(statement().toAst()), statement().toPosition())
             else
                 AnonymousScope(statement_block().toAst(), statement_block().toPosition())
-    return ForLoop(loopregister, datatype, zeropage, loopvar, iterable, scope, toPosition())
+    return ForLoop(loopvar, iterable, scope, toPosition())
 }
 
-
-private fun prog8Parser.ContinuestmtContext.toAst() = Continue(toPosition())
-
 private fun prog8Parser.BreakstmtContext.toAst() = Break(toPosition())
 
-
 private fun prog8Parser.WhileloopContext.toAst(): WhileLoop {
     val condition = expression().toAst()
     val statements = statement_block()?.toAst() ?: mutableListOf(statement().toAst())
@@ -578,13 +600,20 @@ private fun prog8Parser.WhileloopContext.toAst(): WhileLoop {
     return WhileLoop(condition, scope, toPosition())
 }
 
-
 private fun prog8Parser.RepeatloopContext.toAst(): RepeatLoop {
+    val iterations = expression()?.toAst()
+    val statements = statement_block()?.toAst() ?: mutableListOf(statement().toAst())
+    val scope = AnonymousScope(statements, statement_block()?.toPosition()
+            ?: statement().toPosition())
+    return RepeatLoop(iterations, scope, toPosition())
+}
+
+private fun prog8Parser.UntilloopContext.toAst(): UntilLoop {
     val untilCondition = expression().toAst()
     val statements = statement_block()?.toAst() ?: mutableListOf(statement().toAst())
     val scope = AnonymousScope(statements, statement_block()?.toPosition()
             ?: statement().toPosition())
-    return RepeatLoop(scope, untilCondition, toPosition())
+    return UntilLoop(scope, untilCondition, toPosition())
 }
 
 private fun prog8Parser.WhenstmtContext.toAst(): WhenStatement {
@@ -596,10 +625,10 @@ private fun prog8Parser.WhenstmtContext.toAst(): WhenStatement {
 private fun prog8Parser.When_choiceContext.toAst(): WhenChoice {
     val values = expression_list()?.toAst()
     val stmt = statement()?.toAst()
-    val stmt_block = statement_block()?.toAst()?.toMutableList() ?: mutableListOf()
+    val stmtBlock = statement_block()?.toAst()?.toMutableList() ?: mutableListOf()
     if(stmt!=null)
-        stmt_block.add(stmt)
-    val scope = AnonymousScope(stmt_block, toPosition())
+        stmtBlock.add(stmt)
+    val scope = AnonymousScope(stmtBlock, toPosition())
     return WhenChoice(values, scope, toPosition())
 }
 
@@ -643,4 +672,3 @@ internal fun unescape(str: String, position: Position): String {
     }
     return result.joinToString("")
 }
-

compiler/src/prog8/ast/base/Base.kt

@@ -1,7 +1,8 @@
 package prog8.ast.base
 
 import prog8.ast.Node
-import prog8.compiler.target.c64.MachineDefinition
+import prog8.compiler.target.CompilationTarget
+
 
 /**************************** AST Data classes ****************************/
 
@@ -12,7 +13,6 @@ enum class DataType {
     WORD,               // pass by value
     FLOAT,              // pass by value
     STR,                // pass by reference
-    STR_S,              // pass by reference
     ARRAY_UB,           // pass by reference
     ARRAY_B,            // pass by reference
     ARRAY_UW,           // pass by reference
@@ -24,15 +24,14 @@ enum class DataType {
      * is the type assignable to the given other type?
      */
     infix fun isAssignableTo(targetType: DataType) =
-            // what types are assignable to others without loss of precision?
+            // what types are assignable to others, perhaps via a typecast, without loss of precision?
             when(this) {
                 UBYTE -> targetType in setOf(UBYTE, WORD, UWORD, FLOAT)
                 BYTE -> targetType in setOf(BYTE, WORD, FLOAT)
                 UWORD -> targetType in setOf(UWORD, FLOAT)
                 WORD -> targetType in setOf(WORD, FLOAT)
                 FLOAT -> targetType == FLOAT
-                STR -> targetType == STR || targetType==STR_S
-                STR_S -> targetType == STR || targetType==STR_S
+                STR -> targetType == STR
                 in ArrayDatatypes -> targetType == this
                 else -> false
             }
@@ -58,14 +57,14 @@ enum class DataType {
         return when(this) {
             in ByteDatatypes -> 1
             in WordDatatypes -> 2
-            FLOAT -> MachineDefinition.Mflpt5.MemorySize
+            FLOAT -> CompilationTarget.machine.FLOAT_MEM_SIZE
             in PassByReferenceDatatypes -> 2
             else -> -9999999
         }
     }
 }
 
-enum class Register {
+enum class CpuRegister {
     A,
     X,
     Y
@@ -77,14 +76,23 @@ enum class RegisterOrPair {
     Y,
     AX,
     AY,
-    XY
+    XY;
+
+    companion object {
+        val names by lazy { values().map { it.toString()} }
+    }
+
 }       // only used in parameter and return value specs in asm subroutines
 
 enum class Statusflag {
     Pc,
     Pz,
     Pv,
-    Pn
+    Pn;
+
+    companion object {
+        val names by lazy { values().map { it.toString()} }
+    }
 }
 
 enum class BranchCondition {
@@ -112,10 +120,9 @@ val ByteDatatypes = setOf(DataType.UBYTE, DataType.BYTE)
 val WordDatatypes = setOf(DataType.UWORD, DataType.WORD)
 val IntegerDatatypes = setOf(DataType.UBYTE, DataType.BYTE, DataType.UWORD, DataType.WORD)
 val NumericDatatypes = setOf(DataType.UBYTE, DataType.BYTE, DataType.UWORD, DataType.WORD, DataType.FLOAT)
-val StringDatatypes = setOf(DataType.STR, DataType.STR_S)
 val ArrayDatatypes = setOf(DataType.ARRAY_UB, DataType.ARRAY_B, DataType.ARRAY_UW, DataType.ARRAY_W, DataType.ARRAY_F)
 val IterableDatatypes = setOf(
-        DataType.STR, DataType.STR_S,
+        DataType.STR,
         DataType.ARRAY_UB, DataType.ARRAY_B,
         DataType.ARRAY_UW, DataType.ARRAY_W,
         DataType.ARRAY_F)
@@ -123,12 +130,18 @@ val PassByValueDatatypes = NumericDatatypes
 val PassByReferenceDatatypes = IterableDatatypes.plus(DataType.STRUCT)
 val ArrayElementTypes = mapOf(
         DataType.STR to DataType.UBYTE,
-        DataType.STR_S to DataType.UBYTE,
         DataType.ARRAY_B to DataType.BYTE,
         DataType.ARRAY_UB to DataType.UBYTE,
         DataType.ARRAY_W to DataType.WORD,
         DataType.ARRAY_UW to DataType.UWORD,
         DataType.ARRAY_F to DataType.FLOAT)
+val ElementArrayTypes = mapOf(
+        DataType.BYTE to DataType.ARRAY_B,
+        DataType.UBYTE to DataType.ARRAY_UB,
+        DataType.WORD to DataType.ARRAY_W,
+        DataType.UWORD to DataType.ARRAY_UW,
+        DataType.FLOAT to DataType.ARRAY_F
+)
 
 // find the parent node of a specific type or interface
 // (useful to figure out in what namespace/block something is defined, etc)
@@ -146,8 +159,15 @@ object ParentSentinel : Node {
     override val position = Position("<<sentinel>>", 0, 0, 0)
     override var parent: Node = this
     override fun linkParents(parent: Node) {}
+    override fun replaceChildNode(node: Node, replacement: Node) {
+        replacement.parent = this
+    }
 }
 
 data class Position(val file: String, val line: Int, val startCol: Int, val endCol: Int) {
     override fun toString(): String = "[$file: line $line col ${startCol+1}-${endCol+1}]"
+
+    companion object {
+        val DUMMY = Position("<dummy>", 0, 0, 0)
+    }
 }

compiler/src/prog8/ast/base/ErrorReporting.kt

@@ -3,35 +3,42 @@ package prog8.ast.base
 import prog8.parser.ParsingFailedError
 
 
-fun printErrors(errors: List<Any>, moduleName: String) {
-    val reportedMessages = mutableSetOf<String>()
-    print("\u001b[91m")  // bright red
-    errors.forEach {
-        val msg = it.toString()
-        if(msg !in reportedMessages) {
-            System.err.println(msg)
-            reportedMessages.add(msg)
-        }
+class ErrorReporter {
+    private enum class MessageSeverity {
+        WARNING,
+        ERROR
     }
-    print("\u001b[0m")  // reset color
-    if(reportedMessages.isNotEmpty())
-        throw ParsingFailedError("There are ${reportedMessages.size} errors in module '$moduleName'.")
-}
-
-
-fun printWarning(msg: String, position: Position, detailInfo: String?=null) {
-    print("\u001b[93m")  // bright yellow
-    print("$position Warning: $msg")
-    if(detailInfo==null)
-        print("\n")
-    else
-        println(": $detailInfo\n")
-    print("\u001b[0m")  // normal
-}
-
-
-fun printWarning(msg: String) {
-    print("\u001b[93m")  // bright yellow
-    print("Warning: $msg")
-    print("\u001b[0m\n")  // normal
+    private class CompilerMessage(val severity: MessageSeverity, val message: String, val position: Position)
+
+    private val messages = mutableListOf<CompilerMessage>()
+    private val alreadyReportedMessages = mutableSetOf<String>()
+
+    fun err(msg: String, position: Position) = messages.add(CompilerMessage(MessageSeverity.ERROR, msg, position))
+    fun warn(msg: String, position: Position) = messages.add(CompilerMessage(MessageSeverity.WARNING, msg, position))
+
+    fun handle() {
+        var numErrors = 0
+        var numWarnings = 0
+        messages.forEach {
+            when(it.severity) {
+                MessageSeverity.ERROR -> System.err.print("\u001b[91m")  // bright red
+                MessageSeverity.WARNING -> System.err.print("\u001b[93m")  // bright yellow
+            }
+            val msg = "${it.position} ${it.severity} ${it.message}".trim()
+            if(msg !in alreadyReportedMessages) {
+                System.err.println(msg)
+                alreadyReportedMessages.add(msg)
+                when(it.severity) {
+                    MessageSeverity.WARNING -> numWarnings++
+                    MessageSeverity.ERROR -> numErrors++
+                }
+            }
+            System.err.print("\u001b[0m")  // reset color
+        }
+        messages.clear()
+        if(numErrors>0)
+            throw ParsingFailedError("There are $numErrors errors and $numWarnings warnings.")
+    }
+
+    fun isEmpty() = messages.isEmpty()
 }

compiler/src/prog8/ast/base/Errors.kt

@@ -2,21 +2,17 @@ package prog8.ast.base
 
 import prog8.ast.expressions.IdentifierReference
 
-class FatalAstException (override var message: String) : Exception(message)
+open class FatalAstException (override var message: String) : Exception(message)
 
 open class AstException (override var message: String) : Exception(message)
 
-class SyntaxError(override var message: String, val position: Position) : AstException(message) {
+open class SyntaxError(override var message: String, val position: Position) : AstException(message) {
     override fun toString() = "$position Syntax error: $message"
 }
 
-class NameError(override var message: String, val position: Position) : AstException(message) {
-    override fun toString() = "$position Name error: $message"
-}
-
-open class ExpressionError(message: String, val position: Position) : AstException(message) {
+class ExpressionError(message: String, val position: Position) : AstException(message) {
     override fun toString() = "$position Error: $message"
 }
 
 class UndefinedSymbolError(symbol: IdentifierReference)
-    : ExpressionError("undefined symbol: ${symbol.nameInSource.joinToString(".")}", symbol.position)
+    : SyntaxError("undefined symbol: ${symbol.nameInSource.joinToString(".")}", symbol.position)

compiler/src/prog8/ast/base/Extensions.kt

@@ -4,62 +4,67 @@ import prog8.ast.Module
 import prog8.ast.Program
 import prog8.ast.processing.*
 import prog8.compiler.CompilationOptions
-import prog8.compiler.target.c64.codegen2.AnonymousScopeVarsCleanup
-import prog8.optimizer.FlattenAnonymousScopesAndRemoveNops
+import prog8.compiler.BeforeAsmGenerationAstChanger
 
 
-// the name of the subroutine that should be called for every block to initialize its variables
-internal const val initvarsSubName="prog8_init_vars"
-
-
-internal fun Program.removeNopsFlattenAnonScopes() {
-    val flattener = FlattenAnonymousScopesAndRemoveNops()
-    flattener.visit(this)
-}
-
-
-internal fun Program.checkValid(compilerOptions: CompilationOptions) {
-    val checker = AstChecker(this, compilerOptions)
+internal fun Program.checkValid(compilerOptions: CompilationOptions, errors: ErrorReporter) {
+    val checker = AstChecker(this, compilerOptions, errors)
     checker.visit(this)
-    printErrors(checker.result(), name)
 }
 
-
-internal fun Program.anonscopeVarsCleanup() {
-    val mover = AnonymousScopeVarsCleanup(this)
-    mover.visit(this)
-    printErrors(mover.result(), name)
+internal fun Program.processAstBeforeAsmGeneration(errors: ErrorReporter) {
+    val fixer = BeforeAsmGenerationAstChanger(this, errors)
+    fixer.visit(this)
+    fixer.applyModifications()
 }
 
-
 internal fun Program.reorderStatements() {
-    val initvalueCreator = VarInitValueAndAddressOfCreator(this)
-    initvalueCreator.visit(this)
+    val reorder = StatementReorderer(this)
+    reorder.visit(this)
+    reorder.applyModifications()
+}
 
-    val checker = StatementReorderer(this)
-    checker.visit(this)
+internal fun Program.addTypecasts(errors: ErrorReporter) {
+    val caster = TypecastsAdder(this, errors)
+    caster.visit(this)
+    caster.applyModifications()
+}
+
+internal fun Program.verifyFunctionArgTypes() {
+    val fixer = VerifyFunctionArgTypes(this)
+    fixer.visit(this)
 }
 
 internal fun Module.checkImportedValid() {
-    val checker = ImportedModuleDirectiveRemover()
-    checker.visit(this)
-    printErrors(checker.result(), name)
+    val imr = ImportedModuleDirectiveRemover()
+    imr.visit(this, this.parent)
+    imr.applyModifications()
 }
 
-internal fun Program.checkRecursion() {
-    val checker = AstRecursionChecker(namespace)
+internal fun Program.checkRecursion(errors: ErrorReporter) {
+    val checker = AstRecursionChecker(namespace, errors)
     checker.visit(this)
-    printErrors(checker.result(), name)
+    checker.processMessages(name)
 }
 
+internal fun Program.checkIdentifiers(errors: ErrorReporter) {
 
-internal fun Program.checkIdentifiers() {
-    val checker = AstIdentifiersChecker(this)
-    checker.visit(this)
+    val checker2 = AstIdentifiersChecker(this, errors)
+    checker2.visit(this)
 
-    if(modules.map {it.name}.toSet().size != modules.size) {
-        throw FatalAstException("modules should all be unique")
+    if(errors.isEmpty()) {
+        val transforms = AstVariousTransforms(this)
+        transforms.visit(this)
+        transforms.applyModifications()
     }
 
-    printErrors(checker.result(), name)
+    if (modules.map { it.name }.toSet().size != modules.size) {
+        throw FatalAstException("modules should all be unique")
+    }
+}
+
+internal fun Program.variousCleanups() {
+    val process = VariousCleanups()
+    process.visit(this)
+    process.applyModifications()
 }

compiler/src/prog8/ast/expressions/AstExpressions.kt

@@ -1,23 +1,17 @@
 package prog8.ast.expressions
 
-import prog8.ast.IFunctionCall
-import prog8.ast.INameScope
-import prog8.ast.Node
-import prog8.ast.Program
+import prog8.ast.*
 import prog8.ast.antlr.escape
 import prog8.ast.base.*
-import prog8.ast.processing.IAstModifyingVisitor
+import prog8.ast.processing.AstWalker
 import prog8.ast.processing.IAstVisitor
-import prog8.ast.statements.ArrayIndex
-import prog8.ast.statements.BuiltinFunctionStatementPlaceholder
-import prog8.ast.statements.Subroutine
-import prog8.ast.statements.VarDecl
-import prog8.compiler.HeapValues
-import prog8.compiler.IntegerOrAddressOf
-import prog8.compiler.target.c64.Petscii
+import prog8.ast.statements.*
+import prog8.compiler.target.CompilationTarget
 import prog8.functions.BuiltinFunctions
+import prog8.functions.CannotEvaluateException
 import prog8.functions.NotConstArgumentException
 import prog8.functions.builtinFunctionReturnType
+import java.util.*
 import kotlin.math.abs
 
 
@@ -26,30 +20,30 @@ val associativeOperators = setOf("+", "*", "&", "|", "^", "or", "and", "xor", "=
 
 sealed class Expression: Node {
     abstract fun constValue(program: Program): NumericLiteralValue?
-    abstract fun accept(visitor: IAstModifyingVisitor): Expression
     abstract fun accept(visitor: IAstVisitor)
-    abstract fun referencesIdentifiers(vararg name: String): Boolean     // todo: remove this here and move it into CallGraph instead
-    abstract fun inferType(program: Program): DataType?
+    abstract fun accept(visitor: AstWalker, parent: Node)
+    abstract fun referencesIdentifiers(vararg name: String): Boolean
+    abstract fun inferType(program: Program): InferredTypes.InferredType
+
+    infix fun isSameAs(assigntarget: AssignTarget) = assigntarget.isSameAs(this)
 
     infix fun isSameAs(other: Expression): Boolean {
         if(this===other)
             return true
-        when(this) {
-            is RegisterExpr ->
-                return (other is RegisterExpr && other.register==register)
+        return when(this) {
             is IdentifierReference ->
-                return (other is IdentifierReference && other.nameInSource==nameInSource)
+                (other is IdentifierReference && other.nameInSource==nameInSource)
             is PrefixExpression ->
-                return (other is PrefixExpression && other.operator==operator && other.expression isSameAs expression)
+                (other is PrefixExpression && other.operator==operator && other.expression isSameAs expression)
             is BinaryExpression ->
-                return (other is BinaryExpression && other.operator==operator
+                (other is BinaryExpression && other.operator==operator
                         && other.left isSameAs left
                         && other.right isSameAs right)
             is ArrayIndexedExpression -> {
-                return (other is ArrayIndexedExpression && other.identifier.nameInSource == identifier.nameInSource
+                (other is ArrayIndexedExpression && other.identifier.nameInSource == identifier.nameInSource
                         && other.arrayspec.index isSameAs arrayspec.index)
             }
-            else -> return other==this
+            else -> other==this
         }
     }
 }
@@ -63,11 +57,38 @@ class PrefixExpression(val operator: String, var expression: Expression, overrid
         expression.linkParents(this)
     }
 
+    override fun replaceChildNode(node: Node, replacement: Node) {
+        require(node === expression && replacement is Expression)
+        expression = replacement
+        replacement.parent = this
+    }
+
     override fun constValue(program: Program): NumericLiteralValue? = null
-    override fun accept(visitor: IAstModifyingVisitor) = visitor.visit(this)
     override fun accept(visitor: IAstVisitor) = visitor.visit(this)
+    override fun accept(visitor: AstWalker, parent: Node)= visitor.visit(this, parent)
+
     override fun referencesIdentifiers(vararg name: String) = expression.referencesIdentifiers(*name)
-    override fun inferType(program: Program): DataType? = expression.inferType(program)
+    override fun inferType(program: Program): InferredTypes.InferredType {
+        val inferred = expression.inferType(program)
+        return when(operator) {
+            "+" -> inferred
+            "~", "not" -> {
+                when(inferred.typeOrElse(DataType.STRUCT)) {
+                    in ByteDatatypes -> InferredTypes.knownFor(DataType.UBYTE)
+                    in WordDatatypes -> InferredTypes.knownFor(DataType.UWORD)
+                    else -> inferred
+                }
+            }
+            "-" -> {
+                when(inferred.typeOrElse(DataType.STRUCT)) {
+                    in ByteDatatypes -> InferredTypes.knownFor(DataType.BYTE)
+                    in WordDatatypes -> InferredTypes.knownFor(DataType.WORD)
+                    else -> inferred
+                }
+            }
+            else -> throw FatalAstException("weird prefix expression operator")
+        }
+    }
 
     override fun toString(): String {
         return "Prefix($operator $expression)"
@@ -83,6 +104,16 @@ class BinaryExpression(var left: Expression, var operator: String, var right: Ex
         right.linkParents(this)
     }
 
+    override fun replaceChildNode(node: Node, replacement: Node) {
+        require(replacement is Expression)
+        when {
+            node===left -> left = replacement
+            node===right -> right = replacement
+            else -> throw FatalAstException("invalid replace, no child $node")
+        }
+        replacement.parent = this
+    }
+
     override fun toString(): String {
         return "[$left $operator $right]"
     }
@@ -90,18 +121,26 @@ class BinaryExpression(var left: Expression, var operator: String, var right: Ex
     // binary expression should actually have been optimized away into a single value, before const value was requested...
     override fun constValue(program: Program): NumericLiteralValue? = null
 
-    override fun accept(visitor: IAstModifyingVisitor) = visitor.visit(this)
     override fun accept(visitor: IAstVisitor) = visitor.visit(this)
+    override fun accept(visitor: AstWalker, parent: Node)= visitor.visit(this, parent)
+
     override fun referencesIdentifiers(vararg name: String) = left.referencesIdentifiers(*name) || right.referencesIdentifiers(*name)
-    override fun inferType(program: Program): DataType? {
+    override fun inferType(program: Program): InferredTypes.InferredType {
         val leftDt = left.inferType(program)
         val rightDt = right.inferType(program)
         return when (operator) {
-            "+", "-", "*", "**", "%", "/" -> if (leftDt == null || rightDt == null) null else {
-                try {
-                    commonDatatype(leftDt, rightDt, null, null).first
-                } catch (x: FatalAstException) {
-                    null
+            "+", "-", "*", "**", "%", "/" -> {
+                if (!leftDt.isKnown || !rightDt.isKnown)
+                    InferredTypes.unknown()
+                else {
+                    try {
+                        InferredTypes.knownFor(commonDatatype(
+                                leftDt.typeOrElse(DataType.BYTE),
+                                rightDt.typeOrElse(DataType.BYTE),
+                                null, null).first)
+                    } catch (x: FatalAstException) {
+                        InferredTypes.unknown()
+                    }
                 }
             }
             "&" -> leftDt
@@ -110,7 +149,7 @@ class BinaryExpression(var left: Expression, var operator: String, var right: Ex
             "and", "or", "xor",
             "<", ">",
             "<=", ">=",
-            "==", "!=" -> DataType.UBYTE
+            "==", "!=" -> InferredTypes.knownFor(DataType.UBYTE)
             "<<", ">>" -> leftDt
             else -> throw FatalAstException("resulting datatype check for invalid operator $operator")
         }
@@ -177,7 +216,7 @@ class BinaryExpression(var left: Expression, var operator: String, var right: Ex
 
 class ArrayIndexedExpression(var identifier: IdentifierReference,
                              val arrayspec: ArrayIndex,
-                             override val position: Position) : Expression() {
+                             override val position: Position) : Expression(), IAssignable {
     override lateinit var parent: Node
     override fun linkParents(parent: Node) {
         this.parent = parent
@@ -185,22 +224,31 @@ class ArrayIndexedExpression(var identifier: IdentifierReference,
         arrayspec.linkParents(this)
     }
 
+    override fun replaceChildNode(node: Node, replacement: Node) {
+        when {
+            node===identifier -> identifier = replacement as IdentifierReference
+            node===arrayspec.index -> arrayspec.index = replacement as Expression
+            else -> throw FatalAstException("invalid replace")
+        }
+        replacement.parent = this
+    }
+
     override fun constValue(program: Program): NumericLiteralValue? = null
-    override fun accept(visitor: IAstModifyingVisitor) = visitor.visit(this)
     override fun accept(visitor: IAstVisitor) = visitor.visit(this)
+    override fun accept(visitor: AstWalker, parent: Node)= visitor.visit(this, parent)
+
     override fun referencesIdentifiers(vararg name: String) = identifier.referencesIdentifiers(*name)
 
-    override fun inferType(program: Program): DataType? {
+    override fun inferType(program: Program): InferredTypes.InferredType {
         val target = identifier.targetStatement(program.namespace)
         if (target is VarDecl) {
             return when (target.datatype) {
-                in NumericDatatypes -> null
-                in StringDatatypes -> DataType.UBYTE
-                in ArrayDatatypes -> ArrayElementTypes[target.datatype]
-                else -> throw FatalAstException("invalid dt")
+                DataType.STR -> InferredTypes.knownFor(DataType.UBYTE)
+                in ArrayDatatypes -> InferredTypes.knownFor(ArrayElementTypes.getValue(target.datatype))
+                else -> InferredTypes.unknown()
             }
         }
-        return null
+        return InferredTypes.unknown()
     }
 
     override fun toString(): String {
@@ -216,10 +264,17 @@ class TypecastExpression(var expression: Expression, var type: DataType, val imp
         expression.linkParents(this)
     }
 
-    override fun accept(visitor: IAstModifyingVisitor) = visitor.visit(this)
+    override fun replaceChildNode(node: Node, replacement: Node) {
+        require(replacement is Expression && node===expression)
+        expression = replacement
+        replacement.parent = this
+    }
+
     override fun accept(visitor: IAstVisitor) = visitor.visit(this)
+    override fun accept(visitor: AstWalker, parent: Node)= visitor.visit(this, parent)
+
     override fun referencesIdentifiers(vararg name: String) = expression.referencesIdentifiers(*name)
-    override fun inferType(program: Program): DataType? = type
+    override fun inferType(program: Program): InferredTypes.InferredType = InferredTypes.knownFor(type)
     override fun constValue(program: Program): NumericLiteralValue? {
         val cv = expression.constValue(program) ?: return null
         return cv.cast(type)
@@ -240,15 +295,20 @@ data class AddressOf(var identifier: IdentifierReference, override val position:
         identifier.parent=this
     }
 
-    var scopedname: String? = null     // will be set in a later state by the compiler  // TODO get rid of this??
+    override fun replaceChildNode(node: Node, replacement: Node) {
+        require(replacement is IdentifierReference && node===identifier)
+        identifier = replacement
+        replacement.parent = this
+    }
+
     override fun constValue(program: Program): NumericLiteralValue? = null
     override fun referencesIdentifiers(vararg name: String) = false
-    override fun inferType(program: Program) = DataType.UWORD
-    override fun accept(visitor: IAstModifyingVisitor) = visitor.visit(this)
+    override fun inferType(program: Program): InferredTypes.InferredType = InferredTypes.knownFor(DataType.UWORD)
     override fun accept(visitor: IAstVisitor) = visitor.visit(this)
+    override fun accept(visitor: AstWalker, parent: Node)= visitor.visit(this, parent)
 }
 
-class DirectMemoryRead(var addressExpression: Expression, override val position: Position) : Expression() {
+class DirectMemoryRead(var addressExpression: Expression, override val position: Position) : Expression(), IAssignable {
     override lateinit var parent: Node
 
     override fun linkParents(parent: Node) {
@@ -256,10 +316,17 @@ class DirectMemoryRead(var addressExpression: Expression, override val position:
         this.addressExpression.linkParents(this)
     }
 
-    override fun accept(visitor: IAstModifyingVisitor) = visitor.visit(this)
+    override fun replaceChildNode(node: Node, replacement: Node) {
+        require(replacement is Expression && node===addressExpression)
+        addressExpression = replacement
+        replacement.parent = this
+    }
+
     override fun accept(visitor: IAstVisitor) = visitor.visit(this)
+    override fun accept(visitor: AstWalker, parent: Node)= visitor.visit(this, parent)
+
     override fun referencesIdentifiers(vararg name: String) = false
-    override fun inferType(program: Program): DataType? = DataType.UBYTE
+    override fun inferType(program: Program): InferredTypes.InferredType = InferredTypes.knownFor(DataType.UBYTE)
     override fun constValue(program: Program): NumericLiteralValue? = null
 
     override fun toString(): String {
@@ -301,23 +368,27 @@ class NumericLiteralValue(val type: DataType,    // only numerical types allowed
         }
     }
 
-    val asBooleanValue: Boolean = number!=0
+    val asBooleanValue: Boolean = number.toDouble() != 0.0
 
     override fun linkParents(parent: Node) {
         this.parent = parent
     }
 
+    override fun replaceChildNode(node: Node, replacement: Node) {
+        throw FatalAstException("can't replace here")
+    }
+
     override fun referencesIdentifiers(vararg name: String) = false
     override fun constValue(program: Program) = this
 
-    override fun accept(visitor: IAstModifyingVisitor) = visitor.visit(this)
     override fun accept(visitor: IAstVisitor) = visitor.visit(this)
+    override fun accept(visitor: AstWalker, parent: Node)= visitor.visit(this, parent)
 
     override fun toString(): String = "NumericLiteral(${type.name}:$number)"
 
-    override fun inferType(program: Program) = type
+    override fun inferType(program: Program): InferredTypes.InferredType = InferredTypes.knownFor(type)
 
-    override fun hashCode(): Int  = type.hashCode() * 31 xor number.hashCode()
+    override fun hashCode(): Int = Objects.hash(type, number)
 
     override fun equals(other: Any?): Boolean {
         if(other==null || other !is NumericLiteralValue)
@@ -327,7 +398,7 @@ class NumericLiteralValue(val type: DataType,    // only numerical types allowed
 
     operator fun compareTo(other: NumericLiteralValue): Int = number.toDouble().compareTo(other.number.toDouble())
 
-    fun cast(targettype: DataType): NumericLiteralValue? {
+    fun cast(targettype: DataType): NumericLiteralValue {
         if(type==targettype)
             return this
         val numval = number.toDouble()
@@ -382,165 +453,130 @@ class NumericLiteralValue(val type: DataType,    // only numerical types allowed
             }
             else -> {}
         }
-        return null    // invalid type conversion from $this to $targettype
+        throw ExpressionError("can't cast $type into $targettype", position)
     }
 }
 
-class StructLiteralValue(var values: List<Expression>,
-                         override val position: Position): Expression() {
+private var heapIdSequence = 0   // unique ids for strings and arrays "on the heap"
+
+class StringLiteralValue(val value: String,
+                         val altEncoding: Boolean,          // such as: screencodes instead of Petscii for the C64
+                         override val position: Position) : Expression() {
     override lateinit var parent: Node
 
-    override fun linkParents(parent: Node) {
-        this.parent=parent
-        values.forEach { it.linkParents(this) }
-    }
-
-    override fun constValue(program: Program): NumericLiteralValue?  = null
-    override fun accept(visitor: IAstModifyingVisitor) = visitor.visit(this)
-    override fun accept(visitor: IAstVisitor) = visitor.visit(this)
-    override fun referencesIdentifiers(vararg name: String) = values.any { it.referencesIdentifiers(*name) }
-    override fun inferType(program: Program) = DataType.STRUCT
-
-    override fun toString(): String {
-        return "struct{ ${values.joinToString(", ")} }"
-    }
-}
-
-class ReferenceLiteralValue(val type: DataType,     // only reference types allowed here
-                            val str: String? = null,
-                            val array: Array<Expression>? = null,
-                            // actually, at the moment, we don't have struct literals in the language
-                            initHeapId: Int? =null,
-                            override val position: Position) : Expression() {
-    override lateinit var parent: Node
-
-    override fun referencesIdentifiers(vararg name: String) = array?.any { it.referencesIdentifiers(*name) } ?: false
-
-    val isString = type in StringDatatypes
-    val isArray = type in ArrayDatatypes
-    var heapId = initHeapId
-        private set
-
-    init {
-        when(type){
-            in StringDatatypes ->
-                if(str==null) throw FatalAstException("literal value missing strvalue/heapId")
-            in ArrayDatatypes ->
-                if(array==null) throw FatalAstException("literal value missing arrayvalue/heapId")
-            else -> throw FatalAstException("invalid type $type")
-        }
-        if(array==null && str==null)
-            throw FatalAstException("literal ref value without actual value")
-    }
+    val heapId = ++heapIdSequence
 
     override fun linkParents(parent: Node) {
         this.parent = parent
-        array?.forEach {it.linkParents(this)}
     }
 
-    override fun constValue(program: Program): NumericLiteralValue? {
-        // note that we can't handle arrays that only contain constant numbers here anymore
-        // so they're not treated as constants anymore
-        return null
+    override fun replaceChildNode(node: Node, replacement: Node) {
+        throw FatalAstException("can't replace here")
     }
 
-    override fun accept(visitor: IAstModifyingVisitor) = visitor.visit(this)
+    override fun referencesIdentifiers(vararg name: String) = false
+    override fun constValue(program: Program): NumericLiteralValue? = null
     override fun accept(visitor: IAstVisitor) = visitor.visit(this)
+    override fun accept(visitor: AstWalker, parent: Node)= visitor.visit(this, parent)
 
-    override fun toString(): String {
-        val valueStr = when(type) {
-            in StringDatatypes -> "'${escape(str!!)}'"
-            in ArrayDatatypes -> "$array"
-            else -> throw FatalAstException("weird ref type")
-        }
-        return "RefValueLit($type, $valueStr)"
-    }
-
-    override fun inferType(program: Program) = type
-
-    override fun hashCode(): Int {
-        val sh = str?.hashCode() ?: 0x00014567
-        val ah = array?.hashCode() ?: 0x11119876
-        return sh * 31 xor ah xor type.hashCode()
-    }
-
+    override fun toString(): String = "'${escape(value)}'"
+    override fun inferType(program: Program): InferredTypes.InferredType = InferredTypes.knownFor(DataType.STR)
+    operator fun compareTo(other: StringLiteralValue): Int = value.compareTo(other.value)
+    override fun hashCode(): Int = Objects.hash(value, altEncoding)
     override fun equals(other: Any?): Boolean {
-        if(other==null || other !is ReferenceLiteralValue)
+        if(other==null || other !is StringLiteralValue)
             return false
-        if(isArray && other.isArray)
-            return array!!.contentEquals(other.array!!) && heapId==other.heapId
-        if(isString && other.isString)
-            return str==other.str && heapId==other.heapId
+        return value==other.value && altEncoding == other.altEncoding
+    }
+}
 
-        if(type!=other.type)
-            return false
+class ArrayLiteralValue(val type: InferredTypes.InferredType,     // inferred because not all array literals hava a known type yet
+                        val value: Array<Expression>,
+                        override val position: Position) : Expression() {
+    override lateinit var parent: Node
 
-        return compareTo(other) == 0
+    val heapId = ++heapIdSequence
+
+    override fun linkParents(parent: Node) {
+        this.parent = parent
+        value.forEach {it.linkParents(this)}
     }
 
-    operator fun compareTo(other: ReferenceLiteralValue): Int {
-        throw ExpressionError("cannot order compare type $type with ${other.type}", other.position)
+    override fun replaceChildNode(node: Node, replacement: Node) {
+        require(replacement is Expression)
+        val idx = value.indexOfFirst { it===node }
+        value[idx] = replacement
+        replacement.parent = this
     }
 
-    fun cast(targettype: DataType): ReferenceLiteralValue? {
-        if(type==targettype)
+    override fun referencesIdentifiers(vararg name: String) = value.any { it.referencesIdentifiers(*name) }
+    override fun constValue(program: Program): NumericLiteralValue? = null
+    override fun accept(visitor: IAstVisitor) = visitor.visit(this)
+    override fun accept(visitor: AstWalker, parent: Node)= visitor.visit(this, parent)
+
+    override fun toString(): String = "$value"
+    override fun inferType(program: Program): InferredTypes.InferredType = if(type.isKnown) type else guessDatatype(program)
+
+    operator fun compareTo(other: ArrayLiteralValue): Int = throw ExpressionError("cannot order compare arrays", position)
+    override fun hashCode(): Int = Objects.hash(value, type)
+    override fun equals(other: Any?): Boolean {
+        if(other==null || other !is ArrayLiteralValue)
+            return false
+        return type==other.type && value.contentEquals(other.value)
+    }
+
+    fun guessDatatype(program: Program): InferredTypes.InferredType {
+        // Educated guess of the desired array literal's datatype.
+        // If it's inside a for loop, assume the data type of the loop variable is what we want.
+        val forloop = parent as? ForLoop
+        if(forloop != null)  {
+            val loopvarDt = forloop.loopVarDt(program)
+            if(loopvarDt.isKnown) {
+                return if(loopvarDt.typeOrElse(DataType.STRUCT) !in ElementArrayTypes)
+                    InferredTypes.InferredType.unknown()
+                else
+                    InferredTypes.InferredType.known(ElementArrayTypes.getValue(loopvarDt.typeOrElse(DataType.STRUCT)))
+            }
+        }
+
+        // otherwise, select the "biggegst" datatype based on the elements in the array.
+        val datatypesInArray = value.map { it.inferType(program) }
+        require(datatypesInArray.isNotEmpty() && datatypesInArray.all { it.isKnown }) { "can't determine type of empty array" }
+        val dts = datatypesInArray.map { it.typeOrElse(DataType.STRUCT) }
+        return when {
+            DataType.FLOAT in dts -> InferredTypes.InferredType.known(DataType.ARRAY_F)
+            DataType.WORD in dts -> InferredTypes.InferredType.known(DataType.ARRAY_W)
+            DataType.UWORD in dts -> InferredTypes.InferredType.known(DataType.ARRAY_UW)
+            DataType.BYTE in dts -> InferredTypes.InferredType.known(DataType.ARRAY_B)
+            DataType.UBYTE in dts -> InferredTypes.InferredType.known(DataType.ARRAY_UB)
+            else -> InferredTypes.InferredType.unknown()
+        }
+    }
+
+    fun cast(targettype: DataType): ArrayLiteralValue? {
+        if(type.istype(targettype))
             return this
-        when(type) {
-            in StringDatatypes -> {
-                if(targettype in StringDatatypes)
-                    return ReferenceLiteralValue(targettype, str, position = position)
-            }
-            in ArrayDatatypes -> {
-                if(targettype in ArrayDatatypes) {
-                    val elementType = ArrayElementTypes.getValue(targettype)
-                    val castArray = array!!.map{
-                        val num = it as? NumericLiteralValue
-                        if(num==null) {
-                            // an array of UWORDs could possibly also contain AddressOfs
-                            if (elementType != DataType.UWORD || it !is AddressOf)
-                                throw FatalAstException("weird array element $it")
-                            it
-                        } else {
-                            num.cast(elementType)!!
-                        }
-                    }.toTypedArray()
-                    return ReferenceLiteralValue(targettype, null, array=castArray, position = position)
+        if(targettype in ArrayDatatypes) {
+            val elementType = ArrayElementTypes.getValue(targettype)
+            val castArray = value.map{
+                val num = it as? NumericLiteralValue
+                if(num==null) {
+                    // an array of UWORDs could possibly also contain AddressOfs, other stuff can't be casted
+                    if (elementType != DataType.UWORD || it !is AddressOf)
+                        return null
+                    it
+                } else {
+                    try {
+                        num.cast(elementType)
+                    } catch(x: ExpressionError) {
+                        return null
+                    }
                 }
-            }
-            else -> {}
+            }.toTypedArray()
+            return ArrayLiteralValue(InferredTypes.InferredType.known(targettype), castArray, position = position)
         }
         return null    // invalid type conversion from $this to $targettype
     }
-
-    fun addToHeap(heap: HeapValues) {
-        if (heapId != null) return
-        if (str != null) {
-            heapId = heap.addString(type, str)
-        }
-        else if (array!=null) {
-            if(array.any {it is AddressOf }) {
-                val intArrayWithAddressOfs = array.map {
-                    when (it) {
-                        is AddressOf -> IntegerOrAddressOf(null, it)
-                        is NumericLiteralValue -> IntegerOrAddressOf(it.number.toInt(), null)
-                        else -> throw FatalAstException("invalid datatype in array")
-                    }
-                }
-                heapId = heap.addIntegerArray(type, intArrayWithAddressOfs.toTypedArray())
-            } else {
-                val valuesInArray = array.map { (it as? NumericLiteralValue)?.number }
-                if(null !in valuesInArray) {
-                    heapId = if (type == DataType.ARRAY_F) {
-                        val doubleArray = valuesInArray.map { it!!.toDouble() }.toDoubleArray()
-                        heap.addDoublesArray(doubleArray)
-                    } else {
-                        val integerArray = valuesInArray.map { it!!.toInt() }
-                        heap.addIntegerArray(type, integerArray.map { IntegerOrAddressOf(it, null) }.toTypedArray())
-                    }
-                }
-            }
-        }
-    }
 }
 
 class RangeExpr(var from: Expression,
@@ -556,22 +592,33 @@ class RangeExpr(var from: Expression,
         step.linkParents(this)
     }
 
+    override fun replaceChildNode(node: Node, replacement: Node) {
+        require(replacement is Expression)
+        when {
+            from===node -> from=replacement
+            to===node -> to=replacement
+            step===node -> step=replacement
+            else -> throw FatalAstException("invalid replacement")
+        }
+        replacement.parent = this
+    }
+
     override fun constValue(program: Program): NumericLiteralValue? = null
-    override fun accept(visitor: IAstModifyingVisitor) = visitor.visit(this)
     override fun accept(visitor: IAstVisitor) = visitor.visit(this)
+    override fun accept(visitor: AstWalker, parent: Node)= visitor.visit(this, parent)
+
     override fun referencesIdentifiers(vararg name: String): Boolean  = from.referencesIdentifiers(*name) || to.referencesIdentifiers(*name)
-    override fun inferType(program: Program): DataType? {
+    override fun inferType(program: Program): InferredTypes.InferredType {
         val fromDt=from.inferType(program)
         val toDt=to.inferType(program)
         return when {
-            fromDt==null || toDt==null -> null
-            fromDt== DataType.UBYTE && toDt== DataType.UBYTE -> DataType.ARRAY_UB
-            fromDt== DataType.UWORD && toDt== DataType.UWORD -> DataType.ARRAY_UW
-            fromDt== DataType.STR && toDt== DataType.STR -> DataType.STR
-            fromDt== DataType.STR_S && toDt== DataType.STR_S -> DataType.STR_S
-            fromDt== DataType.WORD || toDt== DataType.WORD -> DataType.ARRAY_W
-            fromDt== DataType.BYTE || toDt== DataType.BYTE -> DataType.ARRAY_B
-            else -> DataType.ARRAY_UB
+            !fromDt.isKnown || !toDt.isKnown -> InferredTypes.unknown()
+            fromDt istype DataType.UBYTE && toDt istype DataType.UBYTE -> InferredTypes.knownFor(DataType.ARRAY_UB)
+            fromDt istype DataType.UWORD && toDt istype DataType.UWORD -> InferredTypes.knownFor(DataType.ARRAY_UW)
+            fromDt istype DataType.STR && toDt istype DataType.STR -> InferredTypes.knownFor(DataType.STR)
+            fromDt istype DataType.WORD || toDt istype DataType.WORD -> InferredTypes.knownFor(DataType.ARRAY_W)
+            fromDt istype DataType.BYTE || toDt istype DataType.BYTE -> InferredTypes.knownFor(DataType.ARRAY_B)
+            else -> InferredTypes.knownFor(DataType.ARRAY_UB)
         }
     }
     override fun toString(): String {
@@ -589,12 +636,12 @@ class RangeExpr(var from: Expression,
     fun toConstantIntegerRange(): IntProgression? {
         val fromVal: Int
         val toVal: Int
-        val fromRlv = from as? ReferenceLiteralValue
-        val toRlv = to as? ReferenceLiteralValue
-        if(fromRlv!=null && fromRlv.isString && toRlv!=null && toRlv.isString) {
-            // string range -> int range over petscii values
-            fromVal = Petscii.encodePetscii(fromRlv.str!!, true)[0].toInt()
-            toVal = Petscii.encodePetscii(toRlv.str!!, true)[0].toInt()
+        val fromString = from as? StringLiteralValue
+        val toString = to as? StringLiteralValue
+        if(fromString!=null && toString!=null ) {
+            // string range -> int range over character values
+            fromVal = CompilationTarget.encodeString(fromString.value, fromString.altEncoding)[0].toInt()
+            toVal = CompilationTarget.encodeString(toString.value, fromString.altEncoding)[0].toInt()
         } else {
             val fromLv = from as? NumericLiteralValue
             val toLv = to as? NumericLiteralValue
@@ -605,40 +652,26 @@ class RangeExpr(var from: Expression,
             toVal = toLv.number.toInt()
         }
         val stepVal = (step as? NumericLiteralValue)?.number?.toInt() ?: 1
-        return when {
-            fromVal <= toVal -> when {
-                stepVal <= 0 -> IntRange.EMPTY
-                stepVal == 1 -> fromVal..toVal
-                else -> fromVal..toVal step stepVal
-            }
-            else -> when {
-                stepVal >= 0 -> IntRange.EMPTY
-                stepVal == -1 -> fromVal downTo toVal
-                else -> fromVal downTo toVal step abs(stepVal)
-            }
+        return makeRange(fromVal, toVal, stepVal)
+    }
+}
+
+internal fun makeRange(fromVal: Int, toVal: Int, stepVal: Int): IntProgression {
+    return when {
+        fromVal <= toVal -> when {
+            stepVal <= 0 -> IntRange.EMPTY
+            stepVal == 1 -> fromVal..toVal
+            else -> fromVal..toVal step stepVal
+        }
+        else -> when {
+            stepVal >= 0 -> IntRange.EMPTY
+            stepVal == -1 -> fromVal downTo toVal
+            else -> fromVal downTo toVal step abs(stepVal)
         }
     }
 }
 
-class RegisterExpr(val register: Register, override val position: Position) : Expression() {
-    override lateinit var parent: Node
-
-    override fun linkParents(parent: Node) {
-        this.parent = parent
-    }
-
-    override fun constValue(program: Program): NumericLiteralValue? = null
-    override fun accept(visitor: IAstModifyingVisitor) = visitor.visit(this)
-    override fun accept(visitor: IAstVisitor) = visitor.visit(this)
-    override fun referencesIdentifiers(vararg name: String): Boolean = register.name in name
-    override fun toString(): String {
-        return "RegisterExpr(register=$register, pos=$position)"
-    }
-
-    override fun inferType(program: Program) = DataType.UBYTE
-}
-
-data class IdentifierReference(val nameInSource: List<String>, override val position: Position) : Expression() {
+data class IdentifierReference(val nameInSource: List<String>, override val position: Position) : Expression(), IAssignable {
     override lateinit var parent: Node
 
     fun targetStatement(namespace: INameScope) =
@@ -650,10 +683,17 @@ data class IdentifierReference(val nameInSource: List<String>, override val posi
     fun targetVarDecl(namespace: INameScope): VarDecl? = targetStatement(namespace) as? VarDecl
     fun targetSubroutine(namespace: INameScope): Subroutine? = targetStatement(namespace) as? Subroutine
 
+    override fun equals(other: Any?) = other is IdentifierReference && other.nameInSource==nameInSource
+    override fun hashCode() = nameInSource.hashCode()
+
     override fun linkParents(parent: Node) {
         this.parent = parent
     }
 
+    override fun replaceChildNode(node: Node, replacement: Node) {
+        throw FatalAstException("can't replace here")
+    }
+
     override fun constValue(program: Program): NumericLiteralValue? {
         val node = program.namespace.lookup(nameInSource, this)
                 ?: throw UndefinedSymbolError(this)
@@ -670,16 +710,17 @@ data class IdentifierReference(val nameInSource: List<String>, override val posi
         return "IdentifierRef($nameInSource)"
     }
 
-    override fun accept(visitor: IAstModifyingVisitor) = visitor.visit(this)
     override fun accept(visitor: IAstVisitor) = visitor.visit(this)
-    override fun referencesIdentifiers(vararg name: String): Boolean = nameInSource.last() in name   // @todo is this correct all the time?
+    override fun accept(visitor: AstWalker, parent: Node)= visitor.visit(this, parent)
 
-    override fun inferType(program: Program): DataType? {
+    override fun referencesIdentifiers(vararg name: String): Boolean = nameInSource.last() in name
+
+    override fun inferType(program: Program): InferredTypes.InferredType {
         val targetStmt = targetStatement(program.namespace)
-        if(targetStmt is VarDecl) {
-            return targetStmt.datatype
+        return if(targetStmt is VarDecl) {
+            InferredTypes.knownFor(targetStmt.datatype)
         } else {
-            throw FatalAstException("cannot get datatype from identifier reference ${this}, pos=$position")
+            InferredTypes.InferredType.unknown()
         }
     }
 
@@ -690,28 +731,32 @@ data class IdentifierReference(val nameInSource: List<String>, override val posi
         val value = (node as? VarDecl)?.value ?: throw FatalAstException("requires a reference value")
         return when (value) {
             is IdentifierReference -> value.heapId(namespace)
-            is ReferenceLiteralValue -> value.heapId ?: throw FatalAstException("refLv is not on the heap: $value")
+            is StringLiteralValue -> value.heapId
+            is ArrayLiteralValue -> value.heapId
             else -> throw FatalAstException("requires a reference value")
         }
     }
-
-    fun withPrefixedName(nameprefix: String): IdentifierReference {
-        val prefixed = nameInSource.dropLast(1) + listOf(nameprefix+nameInSource.last())
-        val new = IdentifierReference(prefixed, position)
-        new.parent = parent
-        return new
-    }
 }
 
 class FunctionCall(override var target: IdentifierReference,
-                   override var arglist: MutableList<Expression>,
+                   override var args: MutableList<Expression>,
                    override val position: Position) : Expression(), IFunctionCall {
     override lateinit var parent: Node
 
     override fun linkParents(parent: Node) {
         this.parent = parent
         target.linkParents(this)
-        arglist.forEach { it.linkParents(this) }
+        args.forEach { it.linkParents(this) }
+    }
+
+    override fun replaceChildNode(node: Node, replacement: Node) {
+        if(node===target)
+            target=replacement as IdentifierReference
+        else {
+            val idx = args.indexOfFirst { it===node }
+            args[idx] = replacement as Expression
+        }
+        replacement.parent = this
     }
 
     override fun constValue(program: Program) = constValue(program, true)
@@ -726,14 +771,14 @@ class FunctionCall(override var target: IdentifierReference,
             if(func!=null) {
                 val exprfunc = func.constExpressionFunc
                 if(exprfunc!=null)
-                    resultValue = exprfunc(arglist, position, program)
+                    resultValue = exprfunc(args, position, program)
                 else if(func.returntype==null)
                     throw ExpressionError("builtin function ${target.nameInSource[0]} can't be used here because it doesn't return a value", position)
             }
 
             if(withDatatypeCheck) {
                 val resultDt = this.inferType(program)
-                if(resultValue==null || resultDt == resultValue.type)
+                if(resultValue==null || resultDt istype resultValue.type)
                     return resultValue
                 throw FatalAstException("evaluated const expression result value doesn't match expected datatype $resultDt, pos=$position")
             } else {
@@ -744,37 +789,42 @@ class FunctionCall(override var target: IdentifierReference,
             // const-evaluating the builtin function call failed.
             return null
         }
+        catch(x: CannotEvaluateException) {
+            // const-evaluating the builtin function call failed.
+            return null
+        }
     }
 
     override fun toString(): String {
         return "FunctionCall(target=$target, pos=$position)"
     }
 
-    override fun accept(visitor: IAstModifyingVisitor) = visitor.visit(this)
     override fun accept(visitor: IAstVisitor) = visitor.visit(this)
-    override fun referencesIdentifiers(vararg name: String): Boolean = target.referencesIdentifiers(*name) || arglist.any{it.referencesIdentifiers(*name)}
+    override fun accept(visitor: AstWalker, parent: Node)= visitor.visit(this, parent)
 
-    override fun inferType(program: Program): DataType? {
+    override fun referencesIdentifiers(vararg name: String): Boolean = target.referencesIdentifiers(*name) || args.any{it.referencesIdentifiers(*name)}
+
+    override fun inferType(program: Program): InferredTypes.InferredType {
         val constVal = constValue(program ,false)
         if(constVal!=null)
-            return constVal.type
-        val stmt = target.targetStatement(program.namespace) ?: return null
+            return InferredTypes.knownFor(constVal.type)
+        val stmt = target.targetStatement(program.namespace) ?: return InferredTypes.unknown()
         when (stmt) {
             is BuiltinFunctionStatementPlaceholder -> {
                 if(target.nameInSource[0] == "set_carry" || target.nameInSource[0]=="set_irqd" ||
                         target.nameInSource[0] == "clear_carry" || target.nameInSource[0]=="clear_irqd") {
-                    return null // these have no return value
+                    return InferredTypes.void() // these have no return value
                 }
-                return builtinFunctionReturnType(target.nameInSource[0], this.arglist, program)
+                return builtinFunctionReturnType(target.nameInSource[0], this.args, program)
             }
             is Subroutine -> {
                 if(stmt.returntypes.isEmpty())
-                    return null     // no return value
+                    return InferredTypes.void()     // no return value
                 if(stmt.returntypes.size==1)
-                    return stmt.returntypes[0]
-                return null     // has multiple return types... so not a single resulting datatype possible
+                    return InferredTypes.knownFor(stmt.returntypes[0])
+                return InferredTypes.unknown()     // has multiple return types... so not a single resulting datatype possible
             }
-            else -> return null
+            else -> return InferredTypes.unknown()
         }
     }
 }

compiler/src/prog8/ast/expressions/InferredTypes.kt

@@ -0,0 +1,60 @@
+package prog8.ast.expressions
+
+import prog8.ast.base.DataType
+import java.util.*
+
+
+object InferredTypes {
+    class InferredType private constructor(val isUnknown: Boolean, val isVoid: Boolean, private var datatype: DataType?) {
+        init {
+            require(!(datatype!=null && (isUnknown || isVoid))) { "invalid combination of args" }
+        }
+
+        val isKnown = datatype!=null
+        fun typeOrElse(alternative: DataType) = if(isUnknown || isVoid) alternative else datatype!!
+        infix fun istype(type: DataType): Boolean = if(isUnknown || isVoid) false else this.datatype==type
+
+        companion object {
+            fun unknown() = InferredType(isUnknown = true, isVoid = false, datatype = null)
+            fun void() = InferredType(isUnknown = false, isVoid = true, datatype = null)
+            fun known(type: DataType) = InferredType(isUnknown = false, isVoid = false, datatype = type)
+        }
+
+        override fun equals(other: Any?): Boolean {
+            if(other !is InferredType)
+                return false
+            return isVoid==other.isVoid && datatype==other.datatype
+        }
+
+        override fun toString(): String {
+            return when {
+                datatype!=null -> datatype.toString()
+                isVoid -> "<void>"
+                else -> "<unknown>"
+            }
+        }
+
+        override fun hashCode(): Int = Objects.hash(isVoid, datatype)
+    }
+
+    private val unknownInstance = InferredType.unknown()
+    private val voidInstance = InferredType.void()
+    private val knownInstances = mapOf(
+            DataType.UBYTE to InferredType.known(DataType.UBYTE),
+            DataType.BYTE to InferredType.known(DataType.BYTE),
+            DataType.UWORD to InferredType.known(DataType.UWORD),
+            DataType.WORD to InferredType.known(DataType.WORD),
+            DataType.FLOAT to InferredType.known(DataType.FLOAT),
+            DataType.STR to InferredType.known(DataType.STR),
+            DataType.ARRAY_UB to InferredType.known(DataType.ARRAY_UB),
+            DataType.ARRAY_B to InferredType.known(DataType.ARRAY_B),
+            DataType.ARRAY_UW to InferredType.known(DataType.ARRAY_UW),
+            DataType.ARRAY_W to InferredType.known(DataType.ARRAY_W),
+            DataType.ARRAY_F to InferredType.known(DataType.ARRAY_F),
+            DataType.STRUCT to InferredType.known(DataType.STRUCT)
+    )
+
+    fun void() = voidInstance
+    fun unknown() = unknownInstance
+    fun knownFor(type: DataType) = knownInstances.getValue(type)
+}

compiler/src/prog8/ast/processing/AstIdentifiersChecker.kt

@@ -1,114 +1,81 @@
 package prog8.ast.processing
 
-import prog8.ast.INameScope
 import prog8.ast.Module
-import prog8.ast.Node
 import prog8.ast.Program
 import prog8.ast.base.*
 import prog8.ast.expressions.*
 import prog8.ast.statements.*
-import prog8.compiler.HeapValues
-import prog8.compiler.target.c64.AssemblyProgram
+import prog8.compiler.target.CompilationTarget
 import prog8.functions.BuiltinFunctions
 
-
-internal class AstIdentifiersChecker(private val program: Program) : IAstModifyingVisitor {
-
-    private val checkResult: MutableList<AstException> = mutableListOf()
-
+internal class AstIdentifiersChecker(private val program: Program, private val errors: ErrorReporter) : IAstVisitor {
     private var blocks = mutableMapOf<String, Block>()
-    private val vardeclsToAdd = mutableMapOf<INameScope, MutableList<VarDecl>>()
-
-    internal fun result(): List<AstException> {
-        return checkResult
-    }
 
     private fun nameError(name: String, position: Position, existing: Statement) {
-        checkResult.add(NameError("name conflict '$name', also defined in ${existing.position.file} line ${existing.position.line}", position))
+        errors.err("name conflict '$name', also defined in ${existing.position.file} line ${existing.position.line}", position)
     }
 
     override fun visit(module: Module) {
-        vardeclsToAdd.clear()
         blocks.clear()  // blocks may be redefined within a different module
+
         super.visit(module)
-        // add any new vardecls to the various scopes
-        for((where, decls) in vardeclsToAdd) {
-            where.statements.addAll(0, decls)
-            decls.forEach { it.linkParents(where as Node) }
-        }
     }
 
-    override fun visit(block: Block): Statement {
+    override fun visit(block: Block) {
         val existing = blocks[block.name]
         if(existing!=null)
             nameError(block.name, block.position, existing)
         else
             blocks[block.name] = block
 
-        return super.visit(block)
+        super.visit(block)
     }
 
-    override fun visit(functionCall: FunctionCall): Expression {
-        if(functionCall.target.nameInSource.size==1 && functionCall.target.nameInSource[0]=="lsb") {
-            // lsb(...) is just an alias for type cast to ubyte, so replace with "... as ubyte"
-            val typecast = TypecastExpression(functionCall.arglist.single(), DataType.UBYTE, false, functionCall.position)
-            typecast.linkParents(functionCall.parent)
-            return super.visit(typecast)
-        }
-        return super.visit(functionCall)
-    }
+    override fun visit(decl: VarDecl) {
+        decl.datatypeErrors.forEach { errors.err(it.message, it.position) }
 
-    override fun visit(decl: VarDecl): Statement {
-        // first, check if there are datatype errors on the vardecl
-        decl.datatypeErrors.forEach { checkResult.add(it) }
-
-        // now check the identifier
         if(decl.name in BuiltinFunctions)
-            // the builtin functions can't be redefined
-            checkResult.add(NameError("builtin function cannot be redefined", decl.position))
+            errors.err("builtin function cannot be redefined", decl.position)
 
-        if(decl.name in AssemblyProgram.opcodeNames)
-            checkResult.add(NameError("can't use a cpu opcode name as a symbol", decl.position))
+        if(decl.name in CompilationTarget.machine.opcodeNames)
+            errors.err("can't use a cpu opcode name as a symbol: '${decl.name}'", decl.position)
 
-        // is it a struct variable? then define all its struct members as mangled names,
-        //    and include the original decl as well.
         if(decl.datatype==DataType.STRUCT) {
-            if(decl.structHasBeenFlattened)
+            if (decl.structHasBeenFlattened)
                 return super.visit(decl)    // don't do this multiple times
 
-            if(decl.struct==null) {
-                checkResult.add(NameError("undefined struct type", decl.position))
+            if (decl.struct == null) {
+                errors.err("undefined struct type", decl.position)
                 return super.visit(decl)
             }
 
-            if(decl.struct!!.statements.any { (it as VarDecl).datatype !in NumericDatatypes})
+            if (decl.struct!!.statements.any { (it as VarDecl).datatype !in NumericDatatypes })
                 return super.visit(decl)     // a non-numeric member, not supported. proper error is given by AstChecker later
 
-            if(decl.value is NumericLiteralValue) {
-                checkResult.add(ExpressionError("you cannot initialize a struct using a single value", decl.position))
+            if (decl.value is NumericLiteralValue) {
+                errors.err("you cannot initialize a struct using a single value", decl.position)
                 return super.visit(decl)
             }
 
-            val decls = decl.flattenStructMembers()
-            decls.add(decl)
-            val result = AnonymousScope(decls, decl.position)
-            result.linkParents(decl.parent)
-            return result
+            if (decl.value != null && decl.value !is ArrayLiteralValue) {
+                errors.err("initializing a struct requires array literal value", decl.value?.position ?: decl.position)
+                return super.visit(decl)
+            }
         }
 
         val existing = program.namespace.lookup(listOf(decl.name), decl)
         if (existing != null && existing !== decl)
             nameError(decl.name, decl.position, existing)
 
-        return super.visit(decl)
+        super.visit(decl)
     }
 
-    override fun visit(subroutine: Subroutine): Statement {
-        if(subroutine.name in AssemblyProgram.opcodeNames) {
-            checkResult.add(NameError("can't use a cpu opcode name as a symbol", subroutine.position))
+    override fun visit(subroutine: Subroutine) {
+        if(subroutine.name in CompilationTarget.machine.opcodeNames) {
+            errors.err("can't use a cpu opcode name as a symbol: '${subroutine.name}'", subroutine.position)
         } else if(subroutine.name in BuiltinFunctions) {
             // the builtin functions can't be redefined
-            checkResult.add(NameError("builtin function cannot be redefined", subroutine.position))
+            errors.err("builtin function cannot be redefined", subroutine.position)
         } else {
             // already reported elsewhere:
             // if (subroutine.parameters.any { it.name in BuiltinFunctions })
@@ -140,256 +107,50 @@ internal class AstIdentifiersChecker(private val program: Program) : IAstModifyi
                     nameError(name, sub.position, subroutine)
             }
 
-            // inject subroutine params as local variables (if they're not there yet) (for non-kernel subroutines and non-asm parameters)
-            // NOTE:
-            // - numeric types BYTE and WORD and FLOAT are passed by value;
-            // - strings, arrays, matrices are passed by reference (their 16-bit address is passed as an uword parameter)
-            // - do NOT do this is the statement can be transformed into an asm subroutine later!
-            if(subroutine.asmAddress==null && !subroutine.canBeAsmSubroutine) {
-                if(subroutine.asmParameterRegisters.isEmpty()) {
-                    subroutine.parameters
-                            .filter { it.name !in namesInSub }
-                            .forEach {
-                                val vardecl = VarDecl(VarDeclType.VAR, it.type, ZeropageWish.NOT_IN_ZEROPAGE, null, it.name, null, null,
-                                        isArray = false, autogeneratedDontRemove = true, position = subroutine.position)
-                                vardecl.linkParents(subroutine)
-                                subroutine.statements.add(0, vardecl)
-                            }
-                }
+            if(subroutine.isAsmSubroutine && subroutine.statements.any{it !is InlineAssembly}) {
+                errors.err("asmsub can only contain inline assembly (%asm)", subroutine.position)
             }
         }
-        return super.visit(subroutine)
+
+        super.visit(subroutine)
     }
 
-    override fun visit(label: Label): Statement {
-        if(label.name in AssemblyProgram.opcodeNames)
-            checkResult.add(NameError("can't use a cpu opcode name as a symbol", label.position))
+    override fun visit(label: Label) {
+        if(label.name in CompilationTarget.machine.opcodeNames)
+            errors.err("can't use a cpu opcode name as a symbol: '${label.name}'", label.position)
 
         if(label.name in BuiltinFunctions) {
             // the builtin functions can't be redefined
-            checkResult.add(NameError("builtin function cannot be redefined", label.position))
+            errors.err("builtin function cannot be redefined", label.position)
         } else {
-            val existing = program.namespace.lookup(listOf(label.name), label)
-            if (existing != null && existing !== label)
-                nameError(label.name, label.position, existing)
-        }
-        return super.visit(label)
-    }
-
-    override fun visit(forLoop: ForLoop): Statement {
-        // If the for loop has a decltype, it means to declare the loopvar inside the loop body
-        // rather than reusing an already declared loopvar from an outer scope.
-        // For loops that loop over an interable variable (instead of a range of numbers) get an
-        // additional interation count variable in their scope.
-        if(forLoop.loopRegister!=null) {
-            if(forLoop.decltype!=null)
-                checkResult.add(SyntaxError("register loop variables have a fixed implicit datatype", forLoop.position))
-            if(forLoop.loopRegister == Register.X)
-                printWarning("writing to the X register is dangerous, because it's used as an internal pointer", forLoop.position)
-        } else {
-            val loopVar = forLoop.loopVar
-            if (loopVar != null) {
-                val varName = loopVar.nameInSource.last()
-                if (forLoop.decltype != null) {
-                    val existing = if (forLoop.body.containsNoCodeNorVars()) null else forLoop.body.lookup(loopVar.nameInSource, forLoop.body.statements.first())
-                    if (existing == null) {
-                        // create the local scoped for loop variable itself
-                        val vardecl = VarDecl(VarDeclType.VAR, forLoop.decltype, forLoop.zeropage, null, varName, null, null,
-                                isArray = false, autogeneratedDontRemove = true, position = loopVar.position)
-                        vardecl.linkParents(forLoop.body)
-                        forLoop.body.statements.add(0, vardecl)
-                        loopVar.parent = forLoop.body   // loopvar 'is defined in the body'
-                    } else if(existing.parent!==forLoop && existing.parent.parent!==forLoop) {
-                        checkResult.add(NameError("for loop var was already defined at ${existing.position}", loopVar.position))
-                    }
-                }
-
-                val validName = forLoop.body.name.replace("<", "").replace(">", "").replace("-", "")
-                val loopvarName = "prog8_loopvar_$validName"
-                if (forLoop.iterable !is RangeExpr) {
-                    val existing = if (forLoop.body.containsNoCodeNorVars()) null else forLoop.body.lookup(listOf(loopvarName), forLoop.body.statements.first())
-                    if (existing == null) {
-                        // create loop iteration counter variable (without value, to avoid an assignment)
-                        val vardecl = VarDecl(VarDeclType.VAR, DataType.UBYTE, ZeropageWish.PREFER_ZEROPAGE, null, loopvarName, null, null,
-                                isArray = false, autogeneratedDontRemove = true, position = loopVar.position)
-                        vardecl.linkParents(forLoop.body)
-                        forLoop.body.statements.add(0, vardecl)
-                        loopVar.parent = forLoop.body   // loopvar 'is defined in the body'
-                    }
-                }
-            }
-        }
-        return super.visit(forLoop)
-    }
-
-    override fun visit(assignTarget: AssignTarget): AssignTarget {
-        if(assignTarget.register== Register.X)
-            printWarning("writing to the X register is dangerous, because it's used as an internal pointer", assignTarget.position)
-        return super.visit(assignTarget)
-    }
-
-    override fun visit(returnStmt: Return): Statement {
-        if(returnStmt.value!=null) {
-            // possibly adjust any literal values returned, into the desired returning data type
-            val subroutine = returnStmt.definingSubroutine()!!
-            if(subroutine.returntypes.size!=1)
-                return returnStmt  // mismatch in number of return values, error will be printed later.
-            val newValue: Expression
-            val lval = returnStmt.value as? NumericLiteralValue
-            if(lval!=null) {
-                val adjusted = lval.cast(subroutine.returntypes.single())
-                newValue = if(adjusted!=null && adjusted !== lval) adjusted else lval
-            } else {
-                newValue = returnStmt.value!!
-            }
-
-            returnStmt.value = newValue
-        }
-        return super.visit(returnStmt)
-    }
-
-    override fun visit(refLiteral: ReferenceLiteralValue): Expression {
-        val litval = super.visit(refLiteral)
-        if(litval is ReferenceLiteralValue) {
-            val vardecl = litval.parent as? VarDecl
-            if (litval.isString) {
-                // intern the string; move it into the heap
-                if (litval.str!!.length !in 1..255)
-                    checkResult.add(ExpressionError("string literal length must be between 1 and 255", litval.position))
+            val existing = label.definingSubroutine()?.getAllLabels(label.name) ?: emptyList()
+            for(el in existing) {
+                if(el === label || el.name != label.name)
+                    continue
                 else {
-                    litval.addToHeap(program.heap)
-                }
-                return if(vardecl!=null)
-                    litval
-                else
-                    makeIdentifierFromRefLv(litval)  // replace the literal string by a identifier reference.
-            } else if (litval.isArray) {
-                if (vardecl!=null) {
-                    return fixupArrayDatatype(litval, vardecl, program.heap)
-                } else {
-                    // fix the datatype of the array (also on the heap) to the 'biggest' datatype in the array
-                    // (we don't know the desired datatype here exactly so we guess)
-                    val datatype = determineArrayDt(litval.array!!) ?: return litval
-                    val litval2 = litval.cast(datatype)!!
-                    litval2.parent = litval.parent
-                    // finally, replace the literal array by a identifier reference.
-                    return makeIdentifierFromRefLv(litval2)
+                    nameError(label.name, label.position, el)
+                    break
                 }
             }
         }
 
-        return litval
+        super.visit(label)
     }
 
-    private fun determineArrayDt(array: Array<Expression>): DataType? {
-        val datatypesInArray = array.mapNotNull { it.inferType(program) }
-        if(datatypesInArray.isEmpty())
-            return null
-        if(DataType.FLOAT in datatypesInArray)
-            return DataType.ARRAY_F
-        if(DataType.WORD in datatypesInArray)
-            return DataType.ARRAY_W
-        if(DataType.UWORD in datatypesInArray)
-            return DataType.ARRAY_UW
-        if(DataType.BYTE in datatypesInArray)
-            return DataType.ARRAY_B
-        if(DataType.UBYTE in datatypesInArray)
-            return DataType.ARRAY_UB
-        return null
+    override fun visit(string: StringLiteralValue) {
+        if (string.value.length !in 1..255)
+            errors.err("string literal length must be between 1 and 255", string.position)
+
+        super.visit(string)
     }
 
-    private fun makeIdentifierFromRefLv(refLiteral: ReferenceLiteralValue): IdentifierReference {
-        // a referencetype literal value that's not declared as a variable
-        // we need to introduce an auto-generated variable for this to be able to refer to the value
-        // note: if the var references the same literal value, it is not yet de-duplicated here.
-        refLiteral.addToHeap(program.heap)
-        val scope = refLiteral.definingScope()
-        var variable = VarDecl.createAuto(refLiteral, program.heap)
-        val existing = scope.lookup(listOf(variable.name), refLiteral)
-        variable = addVarDecl(scope, variable)
-        // replace the reference literal by a identifier reference
-        val identifier = IdentifierReference(listOf(variable.name), variable.position)
-        identifier.parent = refLiteral.parent
-        return identifier
-    }
-
-    override fun visit(addressOf: AddressOf): Expression {
-        // register the scoped name of the referenced identifier
-        val variable= addressOf.identifier.targetVarDecl(program.namespace) ?: return addressOf
-        addressOf.scopedname = variable.scopedname
-        return super.visit(addressOf)
-    }
-
-    override fun visit(structDecl: StructDecl): Statement {
+    override fun visit(structDecl: StructDecl) {
         for(member in structDecl.statements){
             val decl = member as? VarDecl
             if(decl!=null && decl.datatype !in NumericDatatypes)
-                checkResult.add(SyntaxError("structs can only contain numerical types", decl.position))
+                errors.err("structs can only contain numerical types", decl.position)
         }
 
-        return super.visit(structDecl)
+        super.visit(structDecl)
     }
-
-    override fun visit(expr: BinaryExpression): Expression {
-        return when {
-            expr.left is ReferenceLiteralValue ->
-                processBinaryExprWithReferenceVal(expr.left as ReferenceLiteralValue, expr.right, expr)
-            expr.right is ReferenceLiteralValue ->
-                processBinaryExprWithReferenceVal(expr.right as ReferenceLiteralValue, expr.left, expr)
-            else -> super.visit(expr)
-        }
-    }
-
-    private fun processBinaryExprWithReferenceVal(refLv: ReferenceLiteralValue, operand: Expression, expr: BinaryExpression): Expression {
-        // expressions on strings or arrays
-        if(refLv.isString) {
-            val constvalue = operand.constValue(program)
-            if(constvalue!=null) {
-                if (expr.operator == "*") {
-                    // repeat a string a number of times
-                    return ReferenceLiteralValue(refLv.inferType(program),
-                            refLv.str!!.repeat(constvalue.number.toInt()), null, null, expr.position)
-                }
-            }
-            if(expr.operator == "+" && operand is ReferenceLiteralValue) {
-                if (operand.isString) {
-                    // concatenate two strings
-                    return ReferenceLiteralValue(refLv.inferType(program),
-                            "${refLv.str}${operand.str}", null, null, expr.position)
-                }
-            }
-        }
-        return expr
-    }
-
-    private fun addVarDecl(scope: INameScope, variable: VarDecl): VarDecl {
-        if(scope !in vardeclsToAdd)
-            vardeclsToAdd[scope] = mutableListOf()
-        val declList = vardeclsToAdd.getValue(scope)
-        val existing = declList.singleOrNull { it.name==variable.name }
-        return if(existing!=null) {
-            existing
-        } else {
-            declList.add(variable)
-            variable
-        }
-    }
-
-}
-
-internal fun fixupArrayDatatype(array: ReferenceLiteralValue, vardecl: VarDecl, heap: HeapValues): ReferenceLiteralValue {
-    if(array.heapId!=null) {
-        val arrayDt = array.type
-        if(arrayDt!=vardecl.datatype) {
-            // fix the datatype of the array (also on the heap) to match the vardecl
-            val litval2 = array.cast(vardecl.datatype)!!
-            vardecl.value = litval2
-            litval2.linkParents(vardecl)
-            litval2.addToHeap(heap)     // TODO is the previous array discarded from the resulting asm code?
-            return litval2
-        }
-    } else {
-        array.addToHeap(heap)
-    }
-    return array
 }

compiler/src/prog8/ast/processing/AstRecursionChecker.kt

@@ -1,21 +1,23 @@
 package prog8.ast.processing
 
 import prog8.ast.INameScope
-import prog8.ast.base.AstException
+import prog8.ast.base.ErrorReporter
+import prog8.ast.base.Position
 import prog8.ast.expressions.FunctionCall
 import prog8.ast.statements.FunctionCallStatement
 import prog8.ast.statements.Subroutine
 
 
-internal class AstRecursionChecker(private val namespace: INameScope) : IAstVisitor {
+internal class AstRecursionChecker(private val namespace: INameScope,
+                                   private val errors: ErrorReporter) : IAstVisitor {
     private val callGraph = DirectedGraph<INameScope>()
 
-    internal fun result(): List<AstException> {
+    fun processMessages(modulename: String) {
         val cycle = callGraph.checkForCycle()
         if(cycle.isEmpty())
-            return emptyList()
+            return
         val chain = cycle.joinToString(" <-- ") { "${it.name} at ${it.position}" }
-        return listOf(AstException("Program contains recursive subroutine calls, this is not supported. Recursive chain:\n (a subroutine call in) $chain"))
+        errors.err("Program contains recursive subroutine calls, this is not supported. Recursive chain:\n (a subroutine call in) $chain", Position.DUMMY)
     }
 
     override fun visit(functionCallStatement: FunctionCallStatement) {
@@ -44,7 +46,6 @@ internal class AstRecursionChecker(private val namespace: INameScope) : IAstVisi
         super.visit(functionCall)
     }
 
-
     private class DirectedGraph<VT> {
         private val graph = mutableMapOf<VT, MutableSet<VT>>()
         private var uniqueVertices = mutableSetOf<VT>()

compiler/src/prog8/ast/processing/AstVariousTransforms.kt

@@ -0,0 +1,173 @@
+package prog8.ast.processing
+
+import prog8.ast.Node
+import prog8.ast.Program
+import prog8.ast.base.*
+import prog8.ast.expressions.*
+import prog8.ast.statements.*
+
+
+internal class AstVariousTransforms(private val program: Program) : AstWalker() {
+    private val noModifications = emptyList<IAstModification>()
+
+    override fun after(functionCallStatement: FunctionCallStatement, parent: Node): Iterable<IAstModification> {
+        if(functionCallStatement.target.nameInSource == listOf("swap")) {
+            // if x and y are both just identifiers, do not rewrite (there should be asm generation for that)
+            // otherwise:
+            // rewrite swap(x,y) as follows:
+            // - declare a temp variable of the same datatype
+            // - temp = x, x = y, y= temp
+            val first = functionCallStatement.args[0]
+            val second = functionCallStatement.args[1]
+            if(first !is IdentifierReference && second !is IdentifierReference) {
+                val dt = first.inferType(program).typeOrElse(DataType.STRUCT)
+                val tempname = "prog8_swaptmp_${functionCallStatement.hashCode()}"
+                val tempvardecl = VarDecl(VarDeclType.VAR, dt, ZeropageWish.DONTCARE, null, tempname, null, null, isArray = false, autogeneratedDontRemove = true, position = first.position)
+                val tempvar = IdentifierReference(listOf(tempname), first.position)
+                val assignTemp = Assignment(
+                        AssignTarget(tempvar, null, null, first.position),
+                        first,
+                        first.position
+                )
+                val assignFirst = Assignment(
+                        AssignTarget.fromExpr(first),
+                        second,
+                        first.position
+                )
+                val assignSecond = Assignment(
+                        AssignTarget.fromExpr(second),
+                        tempvar,
+                        first.position
+                )
+                val scope = AnonymousScope(mutableListOf(tempvardecl, assignTemp, assignFirst, assignSecond), first.position)
+                return listOf(IAstModification.ReplaceNode(functionCallStatement, scope, parent))
+            }
+        }
+
+        return noModifications
+    }
+
+    override fun before(functionCall: FunctionCall, parent: Node): Iterable<IAstModification> {
+        if(functionCall.target.nameInSource.size==1 && functionCall.target.nameInSource[0]=="lsb") {
+            // lsb(...) is just an alias for type cast to ubyte, so replace with "... as ubyte"
+            val typecast = TypecastExpression(functionCall.args.single(), DataType.UBYTE, false, functionCall.position)
+            return listOf(IAstModification.ReplaceNode(
+                    functionCall, typecast, parent
+            ))
+        }
+
+        return noModifications
+    }
+
+    override fun before(decl: VarDecl, parent: Node): Iterable<IAstModification> {
+        // is it a struct variable? then define all its struct members as mangled names,
+        //    and include the original decl as well.
+        if(decl.datatype==DataType.STRUCT && !decl.structHasBeenFlattened) {
+            val decls = decl.flattenStructMembers()
+            decls.add(decl)
+            val result = AnonymousScope(decls, decl.position)
+            return listOf(IAstModification.ReplaceNode(
+                    decl, result, parent
+            ))
+        }
+
+        return noModifications
+    }
+
+    override fun after(subroutine: Subroutine, parent: Node): Iterable<IAstModification> {
+        // For non-kernel subroutines and non-asm parameters:
+        // inject subroutine params as local variables (if they're not there yet).
+        val symbolsInSub = subroutine.allDefinedSymbols()
+        val namesInSub = symbolsInSub.map{ it.first }.toSet()
+        if(subroutine.asmAddress==null) {
+            if(subroutine.asmParameterRegisters.isEmpty() && subroutine.parameters.isNotEmpty()) {
+                val vars = subroutine.statements.filterIsInstance<VarDecl>().map { it.name }.toSet()
+                if(!vars.containsAll(subroutine.parameters.map{it.name})) {
+                    return subroutine.parameters
+                            .filter { it.name !in namesInSub }
+                            .map {
+                                val vardecl = ParameterVarDecl(it.name, it.type, subroutine.position)
+                                IAstModification.InsertFirst(vardecl, subroutine)
+                            }
+                }
+            }
+        }
+
+        return noModifications
+    }
+
+    override fun before(expr: BinaryExpression, parent: Node): Iterable<IAstModification> {
+        when {
+            expr.left is StringLiteralValue ->
+                return listOf(IAstModification.ReplaceNode(
+                        expr,
+                        processBinaryExprWithString(expr.left as StringLiteralValue, expr.right, expr),
+                        parent
+                ))
+            expr.right is StringLiteralValue ->
+                return listOf(IAstModification.ReplaceNode(
+                        expr,
+                        processBinaryExprWithString(expr.right as StringLiteralValue, expr.left, expr),
+                        parent
+                ))
+        }
+
+        return noModifications
+    }
+
+    override fun after(string: StringLiteralValue, parent: Node): Iterable<IAstModification> {
+        if(string.parent !is VarDecl) {
+            // replace the literal string by a identifier reference to a new local vardecl
+            val vardecl = VarDecl.createAuto(string)
+            val identifier = IdentifierReference(listOf(vardecl.name), vardecl.position)
+            return listOf(
+                    IAstModification.ReplaceNode(string, identifier, parent),
+                    IAstModification.InsertFirst(vardecl, string.definingScope() as Node)
+            )
+        }
+        return noModifications
+    }
+
+    override fun after(array: ArrayLiteralValue, parent: Node): Iterable<IAstModification> {
+        val vardecl = array.parent as? VarDecl
+        if(vardecl!=null) {
+            // adjust the datatype of the array (to an educated guess)
+            val arrayDt = array.type
+            if(!arrayDt.istype(vardecl.datatype)) {
+                val cast = array.cast(vardecl.datatype)
+                if (cast != null && cast!=array)
+                    return listOf(IAstModification.ReplaceNode(vardecl.value!!, cast, vardecl))
+            }
+        } else {
+            val arrayDt = array.guessDatatype(program)
+            if(arrayDt.isKnown) {
+                // this array literal is part of an expression, turn it into an identifier reference
+                val litval2 = array.cast(arrayDt.typeOrElse(DataType.STRUCT))
+                if(litval2!=null && litval2!=array) {
+                    val vardecl2 = VarDecl.createAuto(litval2)
+                    val identifier = IdentifierReference(listOf(vardecl2.name), vardecl2.position)
+                    return listOf(
+                            IAstModification.ReplaceNode(array, identifier, parent),
+                            IAstModification.InsertFirst(vardecl2, array.definingScope() as Node)
+                    )
+                }
+            }
+        }
+        return noModifications
+    }
+
+    private fun processBinaryExprWithString(string: StringLiteralValue, operand: Expression, expr: BinaryExpression): Expression {
+        val constvalue = operand.constValue(program)
+        if(constvalue!=null) {
+            if (expr.operator == "*") {
+                // repeat a string a number of times
+                return StringLiteralValue(string.value.repeat(constvalue.number.toInt()), string.altEncoding, expr.position)
+            }
+        }
+        if(expr.operator == "+" && operand is StringLiteralValue) {
+            // concatenate two strings
+            return StringLiteralValue("${string.value}${operand.value}", string.altEncoding, expr.position)
+        }
+        return expr
+    }
+}

compiler/src/prog8/ast/processing/AstWalker.kt

@@ -0,0 +1,430 @@
+package prog8.ast.processing
+
+import prog8.ast.*
+import prog8.ast.base.FatalAstException
+import prog8.ast.expressions.*
+import prog8.ast.statements.*
+
+
+interface IAstModification {
+    fun perform()
+
+    class Remove(val node: Node, val parent: Node) : IAstModification {
+        override fun perform() {
+            if(parent is INameScope) {
+                if (!parent.statements.remove(node) && parent !is GlobalNamespace)
+                    throw FatalAstException("attempt to remove non-existing node $node")
+            } else {
+                throw FatalAstException("parent of a remove modification is not an INameScope")
+            }
+        }
+    }
+
+    class SetExpression(val setter: (newExpr: Expression) -> Unit, val newExpr: Expression, val parent: Node) : IAstModification {
+        override fun perform() {
+            setter(newExpr)
+            newExpr.linkParents(parent)
+        }
+    }
+
+    class InsertFirst(val stmt: Statement, val parent: Node) : IAstModification {
+        override fun perform() {
+            if(parent is INameScope) {
+                parent.statements.add(0, stmt)
+                stmt.linkParents(parent)
+            } else {
+                throw FatalAstException("parent of an insert modification is not an INameScope")
+            }
+        }
+    }
+
+    class InsertLast(val stmt: Statement, val parent: Node) : IAstModification {
+        override fun perform() {
+            if(parent is INameScope) {
+                parent.statements.add(stmt)
+                stmt.linkParents(parent)
+            } else {
+                throw FatalAstException("parent of an insert modification is not an INameScope")
+            }
+        }
+    }
+
+    class InsertAfter(val after: Statement, val stmt: Statement, val parent: Node) : IAstModification {
+        override fun perform() {
+            if(parent is INameScope) {
+                val idx = parent.statements.indexOfFirst { it===after } + 1
+                parent.statements.add(idx, stmt)
+                stmt.linkParents(parent)
+            } else {
+                throw FatalAstException("parent of an insert modification is not an INameScope")
+            }
+        }
+    }
+
+    class ReplaceNode(val node: Node, val replacement: Node, val parent: Node) : IAstModification {
+        override fun perform() {
+            parent.replaceChildNode(node, replacement)
+            replacement.linkParents(parent)
+        }
+    }
+
+    class SwapOperands(val expr: BinaryExpression): IAstModification {
+        override fun perform() {
+            val tmp = expr.left
+            expr.left = expr.right
+            expr.right = tmp
+        }
+    }
+}
+
+
+abstract class AstWalker {
+    open fun before(addressOf: AddressOf, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun before(array: ArrayLiteralValue, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun before(arrayIndexedExpression: ArrayIndexedExpression, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun before(assignTarget: AssignTarget, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun before(assignment: Assignment, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun before(block: Block, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun before(branchStatement: BranchStatement, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun before(breakStmt: Break, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun before(builtinFunctionStatementPlaceholder: BuiltinFunctionStatementPlaceholder, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun before(decl: VarDecl, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun before(directive: Directive, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun before(expr: BinaryExpression, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun before(expr: PrefixExpression, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun before(forLoop: ForLoop, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun before(repeatLoop: RepeatLoop, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun before(functionCall: FunctionCall, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun before(functionCallStatement: FunctionCallStatement, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun before(identifier: IdentifierReference, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun before(ifStatement: IfStatement, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun before(inlineAssembly: InlineAssembly, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun before(jump: Jump, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun before(label: Label, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun before(memread: DirectMemoryRead, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun before(memwrite: DirectMemoryWrite, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun before(module: Module, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun before(nopStatement: NopStatement, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun before(numLiteral: NumericLiteralValue, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun before(postIncrDecr: PostIncrDecr, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun before(program: Program, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun before(range: RangeExpr, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun before(untilLoop: UntilLoop, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun before(returnStmt: Return, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun before(scope: AnonymousScope, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun before(string: StringLiteralValue, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun before(structDecl: StructDecl, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun before(subroutine: Subroutine, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun before(typecast: TypecastExpression, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun before(whenChoice: WhenChoice, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun before(whenStatement: WhenStatement, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun before(whileLoop: WhileLoop, parent: Node): Iterable<IAstModification> = emptyList()
+
+    open fun after(addressOf: AddressOf, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun after(array: ArrayLiteralValue, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun after(arrayIndexedExpression: ArrayIndexedExpression, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun after(assignTarget: AssignTarget, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun after(assignment: Assignment, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun after(block: Block, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun after(branchStatement: BranchStatement, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun after(breakStmt: Break, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun after(builtinFunctionStatementPlaceholder: BuiltinFunctionStatementPlaceholder, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun after(decl: VarDecl, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun after(directive: Directive, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun after(expr: BinaryExpression, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun after(expr: PrefixExpression, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun after(forLoop: ForLoop, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun after(repeatLoop: RepeatLoop, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun after(functionCall: FunctionCall, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun after(functionCallStatement: FunctionCallStatement, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun after(identifier: IdentifierReference, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun after(ifStatement: IfStatement, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun after(inlineAssembly: InlineAssembly, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun after(jump: Jump, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun after(label: Label, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun after(memread: DirectMemoryRead, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun after(memwrite: DirectMemoryWrite, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun after(module: Module, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun after(nopStatement: NopStatement, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun after(numLiteral: NumericLiteralValue, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun after(postIncrDecr: PostIncrDecr, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun after(program: Program, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun after(range: RangeExpr, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun after(untilLoop: UntilLoop, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun after(returnStmt: Return, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun after(scope: AnonymousScope, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun after(string: StringLiteralValue, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun after(structDecl: StructDecl, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun after(subroutine: Subroutine, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun after(typecast: TypecastExpression, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun after(whenChoice: WhenChoice, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun after(whenStatement: WhenStatement, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun after(whileLoop: WhileLoop, parent: Node): Iterable<IAstModification> = emptyList()
+
+    private val modifications = mutableListOf<Triple<IAstModification, Node, Node>>()
+
+    private fun track(mods: Iterable<IAstModification>, node: Node, parent: Node) {
+        for (it in mods) modifications += Triple(it, node, parent)
+    }
+
+    fun applyModifications(): Int {
+        modifications.forEach {
+            it.first.perform()
+        }
+        val amount = modifications.size
+        modifications.clear()
+        return amount
+    }
+
+    fun visit(program: Program) {
+        track(before(program, program), program, program)
+        program.modules.forEach { it.accept(this, program) }
+        track(after(program, program), program, program)
+    }
+
+    fun visit(module: Module, parent: Node) {
+        track(before(module, parent), module, parent)
+        module.statements.forEach{ it.accept(this, module) }
+        track(after(module, parent), module, parent)
+    }
+
+    fun visit(expr: PrefixExpression, parent: Node) {
+        track(before(expr, parent), expr, parent)
+        expr.expression.accept(this, expr)
+        track(after(expr, parent), expr, parent)
+    }
+
+    fun visit(expr: BinaryExpression, parent: Node) {
+        track(before(expr, parent), expr, parent)
+        expr.left.accept(this, expr)
+        expr.right.accept(this, expr)
+        track(after(expr, parent), expr, parent)
+    }
+
+    fun visit(directive: Directive, parent: Node) {
+        track(before(directive, parent), directive, parent)
+        track(after(directive, parent), directive, parent)
+    }
+
+    fun visit(block: Block, parent: Node) {
+        track(before(block, parent), block, parent)
+        block.statements.forEach { it.accept(this, block) }
+        track(after(block, parent), block, parent)
+    }
+
+    fun visit(decl: VarDecl, parent: Node) {
+        track(before(decl, parent), decl, parent)
+        decl.value?.accept(this, decl)
+        decl.arraysize?.accept(this, decl)
+        track(after(decl, parent), decl, parent)
+    }
+
+    fun visit(subroutine: Subroutine, parent: Node) {
+        track(before(subroutine, parent), subroutine, parent)
+        subroutine.statements.forEach { it.accept(this, subroutine) }
+        track(after(subroutine, parent), subroutine, parent)
+    }
+
+    fun visit(functionCall: FunctionCall, parent: Node) {
+        track(before(functionCall, parent), functionCall, parent)
+        functionCall.target.accept(this, functionCall)
+        functionCall.args.forEach { it.accept(this, functionCall) }
+        track(after(functionCall, parent), functionCall, parent)
+    }
+
+    fun visit(functionCallStatement: FunctionCallStatement, parent: Node) {
+        track(before(functionCallStatement, parent), functionCallStatement, parent)
+        functionCallStatement.target.accept(this, functionCallStatement)
+        functionCallStatement.args.forEach { it.accept(this, functionCallStatement) }
+        track(after(functionCallStatement, parent), functionCallStatement, parent)
+    }
+
+    fun visit(identifier: IdentifierReference, parent: Node) {
+        track(before(identifier, parent), identifier, parent)
+        track(after(identifier, parent), identifier, parent)
+    }
+
+    fun visit(jump: Jump, parent: Node) {
+        track(before(jump, parent), jump, parent)
+        jump.identifier?.accept(this, jump)
+        track(after(jump, parent), jump, parent)
+    }
+
+    fun visit(ifStatement: IfStatement, parent: Node) {
+        track(before(ifStatement, parent), ifStatement, parent)
+        ifStatement.condition.accept(this, ifStatement)
+        ifStatement.truepart.accept(this, ifStatement)
+        ifStatement.elsepart.accept(this, ifStatement)
+        track(after(ifStatement, parent), ifStatement, parent)
+    }
+
+    fun visit(branchStatement: BranchStatement, parent: Node) {
+        track(before(branchStatement, parent), branchStatement, parent)
+        branchStatement.truepart.accept(this, branchStatement)
+        branchStatement.elsepart.accept(this, branchStatement)
+        track(after(branchStatement, parent), branchStatement, parent)
+    }
+
+    fun visit(range: RangeExpr, parent: Node) {
+        track(before(range, parent), range, parent)
+        range.from.accept(this, range)
+        range.to.accept(this, range)
+        range.step.accept(this, range)
+        track(after(range, parent), range, parent)
+    }
+
+    fun visit(label: Label, parent: Node) {
+        track(before(label, parent), label, parent)
+        track(after(label, parent), label, parent)
+    }
+
+    fun visit(numLiteral: NumericLiteralValue, parent: Node) {
+        track(before(numLiteral, parent), numLiteral, parent)
+        track(after(numLiteral, parent), numLiteral, parent)
+    }
+
+    fun visit(string: StringLiteralValue, parent: Node) {
+        track(before(string, parent), string, parent)
+        track(after(string, parent), string, parent)
+    }
+
+    fun visit(array: ArrayLiteralValue, parent: Node) {
+        track(before(array, parent), array, parent)
+        array.value.forEach { v->v.accept(this, array) }
+        track(after(array, parent), array, parent)
+    }
+
+    fun visit(assignment: Assignment, parent: Node) {
+        track(before(assignment, parent), assignment, parent)
+        assignment.target.accept(this, assignment)
+        assignment.value.accept(this, assignment)
+        track(after(assignment, parent), assignment, parent)
+    }
+
+    fun visit(postIncrDecr: PostIncrDecr, parent: Node) {
+        track(before(postIncrDecr, parent), postIncrDecr, parent)
+        postIncrDecr.target.accept(this, postIncrDecr)
+        track(after(postIncrDecr, parent), postIncrDecr, parent)
+    }
+
+    fun visit(breakStmt: Break, parent: Node) {
+        track(before(breakStmt, parent), breakStmt, parent)
+        track(after(breakStmt, parent), breakStmt, parent)
+    }
+
+    fun visit(forLoop: ForLoop, parent: Node) {
+        track(before(forLoop, parent), forLoop, parent)
+        forLoop.loopVar.accept(this, forLoop)
+        forLoop.iterable.accept(this, forLoop)
+        forLoop.body.accept(this, forLoop)
+        track(after(forLoop, parent), forLoop, parent)
+    }
+
+    fun visit(whileLoop: WhileLoop, parent: Node) {
+        track(before(whileLoop, parent), whileLoop, parent)
+        whileLoop.condition.accept(this, whileLoop)
+        whileLoop.body.accept(this, whileLoop)
+        track(after(whileLoop, parent), whileLoop, parent)
+    }
+
+    fun visit(repeatLoop: RepeatLoop, parent: Node) {
+        track(before(repeatLoop, parent), repeatLoop, parent)
+        repeatLoop.iterations?.accept(this, repeatLoop)
+        repeatLoop.body.accept(this, repeatLoop)
+        track(after(repeatLoop, parent), repeatLoop, parent)
+    }
+
+    fun visit(untilLoop: UntilLoop, parent: Node) {
+        track(before(untilLoop, parent), untilLoop, parent)
+        untilLoop.untilCondition.accept(this, untilLoop)
+        untilLoop.body.accept(this, untilLoop)
+        track(after(untilLoop, parent), untilLoop, parent)
+    }
+
+    fun visit(returnStmt: Return, parent: Node) {
+        track(before(returnStmt, parent), returnStmt, parent)
+        returnStmt.value?.accept(this, returnStmt)
+        track(after(returnStmt, parent), returnStmt, parent)
+    }
+
+    fun visit(arrayIndexedExpression: ArrayIndexedExpression, parent: Node) {
+        track(before(arrayIndexedExpression, parent), arrayIndexedExpression, parent)
+        arrayIndexedExpression.identifier.accept(this, arrayIndexedExpression)
+        arrayIndexedExpression.arrayspec.accept(this, arrayIndexedExpression)
+        track(after(arrayIndexedExpression, parent), arrayIndexedExpression, parent)
+    }
+
+    fun visit(assignTarget: AssignTarget, parent: Node) {
+        track(before(assignTarget, parent), assignTarget, parent)
+        assignTarget.arrayindexed?.accept(this, assignTarget)
+        assignTarget.identifier?.accept(this, assignTarget)
+        assignTarget.memoryAddress?.accept(this, assignTarget)
+        track(after(assignTarget, parent), assignTarget, parent)
+    }
+
+    fun visit(scope: AnonymousScope, parent: Node) {
+        track(before(scope, parent), scope, parent)
+        scope.statements.forEach { it.accept(this, scope) }
+        track(after(scope, parent), scope, parent)
+    }
+
+    fun visit(typecast: TypecastExpression, parent: Node) {
+        track(before(typecast, parent), typecast, parent)
+        typecast.expression.accept(this, typecast)
+        track(after(typecast, parent), typecast, parent)
+    }
+
+    fun visit(memread: DirectMemoryRead, parent: Node) {
+        track(before(memread, parent), memread, parent)
+        memread.addressExpression.accept(this, memread)
+        track(after(memread, parent), memread, parent)
+    }
+
+    fun visit(memwrite: DirectMemoryWrite, parent: Node) {
+        track(before(memwrite, parent), memwrite, parent)
+        memwrite.addressExpression.accept(this, memwrite)
+        track(after(memwrite, parent), memwrite, parent)
+    }
+
+    fun visit(addressOf: AddressOf, parent: Node) {
+        track(before(addressOf, parent), addressOf, parent)
+        addressOf.identifier.accept(this, addressOf)
+        track(after(addressOf, parent), addressOf, parent)
+    }
+
+    fun visit(inlineAssembly: InlineAssembly, parent: Node) {
+        track(before(inlineAssembly, parent), inlineAssembly, parent)
+        track(after(inlineAssembly, parent), inlineAssembly, parent)
+    }
+
+    fun visit(builtinFunctionStatementPlaceholder: BuiltinFunctionStatementPlaceholder, parent: Node) {
+        track(before(builtinFunctionStatementPlaceholder, parent), builtinFunctionStatementPlaceholder, parent)
+        track(after(builtinFunctionStatementPlaceholder, parent), builtinFunctionStatementPlaceholder, parent)
+    }
+
+    fun visit(nopStatement: NopStatement, parent: Node) {
+        track(before(nopStatement, parent), nopStatement, parent)
+        track(after(nopStatement, parent), nopStatement, parent)
+    }
+
+    fun visit(whenStatement: WhenStatement, parent: Node) {
+        track(before(whenStatement, parent), whenStatement, parent)
+        whenStatement.condition.accept(this, whenStatement)
+        whenStatement.choices.forEach { it.accept(this, whenStatement) }
+        track(after(whenStatement, parent), whenStatement, parent)
+    }
+
+    fun visit(whenChoice: WhenChoice, parent: Node) {
+        track(before(whenChoice, parent), whenChoice, parent)
+        whenChoice.values?.forEach { it.accept(this, whenChoice) }
+        whenChoice.statements.accept(this, whenChoice)
+        track(after(whenChoice, parent), whenChoice, parent)
+    }
+
+    fun visit(structDecl: StructDecl, parent: Node) {
+        track(before(structDecl, parent), structDecl, parent)
+        structDecl.statements.forEach { it.accept(this, structDecl) }
+        track(after(structDecl, parent), structDecl, parent)
+    }
+}
+

compiler/src/prog8/ast/processing/IAstModifyingVisitor.kt

@@ -1,261 +0,0 @@
-package prog8.ast.processing
-
-import prog8.ast.Module
-import prog8.ast.Program
-import prog8.ast.base.FatalAstException
-import prog8.ast.expressions.*
-import prog8.ast.statements.*
-
-interface IAstModifyingVisitor {
-    fun visit(program: Program) {
-        program.modules.forEach { visit(it) }
-    }
-
-    fun visit(module: Module) {
-        module.statements = module.statements.map { it.accept(this) }.toMutableList()
-    }
-
-    fun visit(expr: PrefixExpression): Expression {
-        expr.expression = expr.expression.accept(this)
-        return expr
-    }
-
-    fun visit(expr: BinaryExpression): Expression {
-        expr.left = expr.left.accept(this)
-        expr.right = expr.right.accept(this)
-        return expr
-    }
-
-    fun visit(directive: Directive): Statement {
-        return directive
-    }
-
-    fun visit(block: Block): Statement {
-        block.statements = block.statements.map { it.accept(this) }.toMutableList()
-        return block
-    }
-
-    fun visit(decl: VarDecl): Statement {
-        decl.value = decl.value?.accept(this)
-        decl.arraysize?.accept(this)
-        return decl
-    }
-
-    fun visit(subroutine: Subroutine): Statement {
-        subroutine.statements = subroutine.statements.map { it.accept(this) }.toMutableList()
-        return subroutine
-    }
-
-    fun visit(functionCall: FunctionCall): Expression {
-        val newtarget = functionCall.target.accept(this)
-        if(newtarget is IdentifierReference)
-            functionCall.target = newtarget
-        else
-            throw FatalAstException("cannot change class of function call target")
-        functionCall.arglist = functionCall.arglist.map { it.accept(this) }.toMutableList()
-        return functionCall
-    }
-
-    fun visit(functionCallStatement: FunctionCallStatement): Statement {
-        val newtarget = functionCallStatement.target.accept(this)
-        if(newtarget is IdentifierReference)
-            functionCallStatement.target = newtarget
-        else
-            throw FatalAstException("cannot change class of function call target")
-        functionCallStatement.arglist = functionCallStatement.arglist.map { it.accept(this) }.toMutableList()
-        return functionCallStatement
-    }
-
-    fun visit(identifier: IdentifierReference): Expression {
-        // note: this is an identifier that is used in an expression.
-        // other identifiers are simply part of the other statements (such as jumps, subroutine defs etc)
-        return identifier
-    }
-
-    fun visit(jump: Jump): Statement {
-        if(jump.identifier!=null) {
-            val ident = jump.identifier.accept(this)
-            if(ident is IdentifierReference && ident!==jump.identifier) {
-                return Jump(null, ident, null, jump.position)
-            }
-        }
-        return jump
-    }
-
-    fun visit(ifStatement: IfStatement): Statement {
-        ifStatement.condition = ifStatement.condition.accept(this)
-        ifStatement.truepart = ifStatement.truepart.accept(this) as AnonymousScope
-        ifStatement.elsepart = ifStatement.elsepart.accept(this) as AnonymousScope
-        return ifStatement
-    }
-
-    fun visit(branchStatement: BranchStatement): Statement {
-        branchStatement.truepart = branchStatement.truepart.accept(this) as AnonymousScope
-        branchStatement.elsepart = branchStatement.elsepart.accept(this) as AnonymousScope
-        return branchStatement
-    }
-
-    fun visit(range: RangeExpr): Expression {
-        range.from = range.from.accept(this)
-        range.to = range.to.accept(this)
-        range.step = range.step.accept(this)
-        return range
-    }
-
-    fun visit(label: Label): Statement {
-        return label
-    }
-
-    fun visit(literalValue: NumericLiteralValue): NumericLiteralValue {
-        return literalValue
-    }
-
-    fun visit(refLiteral: ReferenceLiteralValue): Expression {
-        if(refLiteral.array!=null) {
-            for(av in refLiteral.array.withIndex()) {
-                val newvalue = av.value.accept(this)
-                refLiteral.array[av.index] = newvalue
-            }
-        }
-        return refLiteral
-    }
-
-    fun visit(assignment: Assignment): Statement {
-        assignment.target = assignment.target.accept(this)
-        assignment.value = assignment.value.accept(this)
-        return assignment
-    }
-
-    fun visit(postIncrDecr: PostIncrDecr): Statement {
-        postIncrDecr.target = postIncrDecr.target.accept(this)
-        return postIncrDecr
-    }
-
-    fun visit(contStmt: Continue): Statement {
-        return contStmt
-    }
-
-    fun visit(breakStmt: Break): Statement {
-        return breakStmt
-    }
-
-    fun visit(forLoop: ForLoop): Statement {
-        val newloopvar = forLoop.loopVar?.accept(this)
-        when(newloopvar) {
-            is IdentifierReference -> forLoop.loopVar = newloopvar
-            null -> forLoop.loopVar = null
-            else -> throw FatalAstException("can't change class of loopvar")
-        }
-        forLoop.iterable = forLoop.iterable.accept(this)
-        forLoop.body = forLoop.body.accept(this) as AnonymousScope
-        return forLoop
-    }
-
-    fun visit(whileLoop: WhileLoop): Statement {
-        whileLoop.condition = whileLoop.condition.accept(this)
-        whileLoop.body = whileLoop.body.accept(this) as AnonymousScope
-        return whileLoop
-    }
-
-    fun visit(repeatLoop: RepeatLoop): Statement {
-        repeatLoop.untilCondition = repeatLoop.untilCondition.accept(this)
-        repeatLoop.body = repeatLoop.body.accept(this) as AnonymousScope
-        return repeatLoop
-    }
-
-    fun visit(returnStmt: Return): Statement {
-        returnStmt.value = returnStmt.value?.accept(this)
-        return returnStmt
-    }
-
-    fun visit(arrayIndexedExpression: ArrayIndexedExpression): ArrayIndexedExpression {
-        val ident = arrayIndexedExpression.identifier.accept(this)
-        if(ident is IdentifierReference)
-            arrayIndexedExpression.identifier = ident
-        arrayIndexedExpression.arrayspec.accept(this)
-        return arrayIndexedExpression
-    }
-
-    fun visit(assignTarget: AssignTarget): AssignTarget {
-        val ident = assignTarget.identifier?.accept(this)
-        when (ident) {
-            is IdentifierReference -> assignTarget.identifier = ident
-            null -> assignTarget.identifier = null
-            else -> throw FatalAstException("can't change class of assign target identifier")
-        }
-        assignTarget.arrayindexed = assignTarget.arrayindexed?.accept(this)
-        assignTarget.memoryAddress?.let { visit(it) }
-        return assignTarget
-    }
-
-    fun visit(scope: AnonymousScope): Statement {
-        scope.statements = scope.statements.map { it.accept(this) }.toMutableList()
-        return scope
-    }
-
-    fun visit(typecast: TypecastExpression): Expression {
-        typecast.expression = typecast.expression.accept(this)
-        return typecast
-    }
-
-    fun visit(memread: DirectMemoryRead): Expression {
-        memread.addressExpression = memread.addressExpression.accept(this)
-        return memread
-    }
-
-    fun visit(memwrite: DirectMemoryWrite) {
-        memwrite.addressExpression = memwrite.addressExpression.accept(this)
-    }
-
-    fun visit(addressOf: AddressOf): Expression {
-        val ident = addressOf.identifier.accept(this)
-        if(ident is IdentifierReference)
-            addressOf.identifier = ident
-        else
-            throw FatalAstException("can't change class of addressof identifier")
-        return addressOf
-    }
-
-    fun visit(inlineAssembly: InlineAssembly): Statement {
-        return inlineAssembly
-    }
-
-    fun visit(registerExpr: RegisterExpr): Expression {
-        return registerExpr
-    }
-
-    fun visit(builtinFunctionStatementPlaceholder: BuiltinFunctionStatementPlaceholder): Statement {
-        return builtinFunctionStatementPlaceholder
-    }
-
-    fun visit(nopStatement: NopStatement): Statement {
-        return nopStatement
-    }
-
-    fun visit(whenStatement: WhenStatement): Statement {
-        whenStatement.condition = whenStatement.condition.accept(this)
-        whenStatement.choices.forEach { it.accept(this) }
-        return whenStatement
-    }
-
-    fun visit(whenChoice: WhenChoice) {
-        whenChoice.values = whenChoice.values?.map { it.accept(this) }
-        val stmt = whenChoice.statements.accept(this)
-        if(stmt is AnonymousScope)
-            whenChoice.statements = stmt
-        else {
-            whenChoice.statements = AnonymousScope(mutableListOf(stmt), stmt.position)
-            whenChoice.statements.linkParents(whenChoice)
-        }
-    }
-
-    fun visit(structDecl: StructDecl): Statement {
-        structDecl.statements = structDecl.statements.map{ it.accept(this) }.toMutableList()
-        return structDecl
-    }
-
-    fun visit(structLv: StructLiteralValue): Expression {
-        structLv.values = structLv.values.map { it.accept(this) }
-        return structLv
-    }
-}

compiler/src/prog8/ast/processing/IAstVisitor.kt

@@ -7,7 +7,7 @@ import prog8.ast.statements.*
 
 interface IAstVisitor {
     fun visit(program: Program) {
-        program.modules.forEach { visit(it) }
+        program.modules.forEach { it.accept(this) }
     }
 
     fun visit(module: Module) {
@@ -41,12 +41,12 @@ interface IAstVisitor {
 
     fun visit(functionCall: FunctionCall) {
         functionCall.target.accept(this)
-        functionCall.arglist.forEach { it.accept(this) }
+        functionCall.args.forEach { it.accept(this) }
     }
 
     fun visit(functionCallStatement: FunctionCallStatement) {
         functionCallStatement.target.accept(this)
-        functionCallStatement.arglist.forEach { it.accept(this) }
+        functionCallStatement.args.forEach { it.accept(this) }
     }
 
     fun visit(identifier: IdentifierReference) {
@@ -79,8 +79,11 @@ interface IAstVisitor {
     fun visit(numLiteral: NumericLiteralValue) {
     }
 
-    fun visit(refLiteral: ReferenceLiteralValue) {
-        refLiteral.array?.let { it.forEach { v->v.accept(this) }}
+    fun visit(string: StringLiteralValue) {
+    }
+
+    fun visit(array: ArrayLiteralValue) {
+        array.value.forEach { v->v.accept(this) }
     }
 
     fun visit(assignment: Assignment) {
@@ -92,14 +95,11 @@ interface IAstVisitor {
         postIncrDecr.target.accept(this)
     }
 
-    fun visit(contStmt: Continue) {
-    }
-
     fun visit(breakStmt: Break) {
     }
 
     fun visit(forLoop: ForLoop) {
-        forLoop.loopVar?.accept(this)
+        forLoop.loopVar.accept(this)
         forLoop.iterable.accept(this)
         forLoop.body.accept(this)
     }
@@ -110,10 +110,15 @@ interface IAstVisitor {
     }
 
     fun visit(repeatLoop: RepeatLoop) {
-        repeatLoop.untilCondition.accept(this)
+        repeatLoop.iterations?.accept(this)
         repeatLoop.body.accept(this)
     }
 
+    fun visit(untilLoop: UntilLoop) {
+        untilLoop.untilCondition.accept(this)
+        untilLoop.body.accept(this)
+    }
+
     fun visit(returnStmt: Return) {
         returnStmt.value?.accept(this)
     }
@@ -152,9 +157,6 @@ interface IAstVisitor {
     fun visit(inlineAssembly: InlineAssembly) {
     }
 
-    fun visit(registerExpr: RegisterExpr) {
-    }
-
     fun visit(builtinFunctionStatementPlaceholder: BuiltinFunctionStatementPlaceholder) {
     }
 
@@ -174,8 +176,4 @@ interface IAstVisitor {
     fun visit(structDecl: StructDecl) {
         structDecl.statements.forEach { it.accept(this) }
     }
-
-    fun visit(structLv: StructLiteralValue) {
-        structLv.values.forEach { it.accept(this) }
-    }
 }

compiler/src/prog8/ast/processing/ImportedModuleDirectiveRemover.kt

@@ -1,36 +1,21 @@
 package prog8.ast.processing
 
-import prog8.ast.Module
-import prog8.ast.base.SyntaxError
-import prog8.ast.base.printWarning
+import prog8.ast.Node
 import prog8.ast.statements.Directive
-import prog8.ast.statements.Statement
 
-internal class ImportedModuleDirectiveRemover : IAstModifyingVisitor {
-    private val checkResult: MutableList<SyntaxError> = mutableListOf()
-
-    internal fun result(): List<SyntaxError> {
-        return checkResult
-    }
 
+internal class ImportedModuleDirectiveRemover: AstWalker() {
     /**
      * Most global directives don't apply for imported modules, so remove them
      */
-    override fun visit(module: Module) {
-        super.visit(module)
-        val newStatements : MutableList<Statement> = mutableListOf()
 
-        val moduleLevelDirectives = listOf("%output", "%launcher", "%zeropage", "%zpreserved", "%address")
-        for (sourceStmt in module.statements) {
-            val stmt = sourceStmt.accept(this)
-            if(stmt is Directive && stmt.parent is Module) {
-                if(stmt.directive in moduleLevelDirectives) {
-                    printWarning("ignoring module directive because it was imported", stmt.position, stmt.directive)
-                    continue
-                }
-            }
-            newStatements.add(stmt)
+    private val moduleLevelDirectives = listOf("%output", "%launcher", "%zeropage", "%zpreserved", "%address")
+    private val noModifications = emptyList<IAstModification>()
+
+    override fun before(directive: Directive, parent: Node): Iterable<IAstModification> {
+        if(directive.directive in moduleLevelDirectives) {
+            return listOf(IAstModification.Remove(directive, parent))
         }
-        module.statements = newStatements
+        return noModifications
     }
 }

compiler/src/prog8/ast/processing/ReflectionAstWalker.kt

@@ -0,0 +1,71 @@
+package prog8.ast.processing
+
+
+/*
+This is here for reference only, reflection based ast walking is very slow
+when compared to the more verbose visitor pattern interfaces.
+Too bad, because the code is very small
+*/
+
+
+//import prog8.ast.NoAstWalk
+//import prog8.ast.Node
+//import prog8.ast.Program
+//import prog8.ast.base.Position
+//import prog8.ast.expressions.BinaryExpression
+//import prog8.ast.expressions.NumericLiteralValue
+//import kotlin.reflect.KClass
+//import kotlin.reflect.KVisibility
+//import kotlin.reflect.full.declaredMemberProperties
+//import kotlin.reflect.full.isSubtypeOf
+//import kotlin.reflect.full.starProjectedType
+//
+//
+//class ReflectionAstWalker {
+//    private val nodeType = Node::class.starProjectedType
+//    private val collectionType = Collection::class.starProjectedType
+//
+//
+//    fun walk(node: Node, nesting: Int) {
+//        val nodetype: KClass<out Node> = node::class
+//        val indent = "  ".repeat(nesting)
+//        //println("$indent VISITING ${nodetype.simpleName}")
+//        val visibleAstMembers = nodetype.declaredMemberProperties.filter {
+//            it.visibility!=KVisibility.PRIVATE && !it.isLateinit &&
+//                    !(it.annotations.any{a->a is NoAstWalk})
+//        }
+//        for(prop in visibleAstMembers) {
+//            if(prop.returnType.isSubtypeOf(nodeType)) {
+//                // println("$indent +PROP: ${prop.name}")
+//                walk(prop.call(node) as Node, nesting + 1)
+//            }
+//            else if(prop.returnType.isSubtypeOf(collectionType)) {
+//                val elementType = prop.returnType.arguments.single().type
+//                if(elementType!=null && elementType.isSubtypeOf(nodeType)) {
+//                    val nodes = prop.call(node) as Collection<Node>
+//                    nodes.forEach { walk(it, nesting+1) }
+//                }
+//            }
+//        }
+//    }
+//    fun walk(program: Program) {
+//        for(module in program.modules) {
+//            println("---MODULE $module---")
+//            walk(module, 0)
+//        }
+//    }
+//}
+//
+//
+//fun main() {
+//    val ast = BinaryExpression(
+//            NumericLiteralValue.optimalInteger(100, Position.DUMMY),
+//            "+",
+//            NumericLiteralValue.optimalInteger(200, Position.DUMMY),
+//            Position.DUMMY
+//    )
+//
+//    val walker = ReflectionAstWalker()
+//    walker.walk(ast,0)
+//
+//}

compiler/src/prog8/ast/processing/StatementReorderer.kt

@@ -1,400 +1,228 @@
 package prog8.ast.processing
 
 import prog8.ast.*
-import prog8.ast.base.DataType
-import prog8.ast.base.FatalAstException
-import prog8.ast.base.initvarsSubName
-import prog8.ast.base.printWarning
+import prog8.ast.base.*
 import prog8.ast.expressions.*
 import prog8.ast.statements.*
-import prog8.functions.BuiltinFunctions
 
 
-fun flattenStructAssignmentFromIdentifier(structAssignment: Assignment, program: Program): List<Assignment> {
-    val identifier = structAssignment.target.identifier!!
-    val identifierName = identifier.nameInSource.single()
-    val targetVar = identifier.targetVarDecl(program.namespace)!!
-    val struct = targetVar.struct!!
-    when {
-        structAssignment.value is IdentifierReference -> {
-            val sourceVar = (structAssignment.value as IdentifierReference).targetVarDecl(program.namespace)!!
-            if (sourceVar.struct == null)
-                throw FatalAstException("can only assign arrays or structs to structs")
-            // struct memberwise copy
-            val sourceStruct = sourceVar.struct!!
-            if(sourceStruct!==targetVar.struct) {
-                // structs are not the same in assignment
-                return listOf()     // error will be printed elsewhere
-            }
-            return struct.statements.zip(sourceStruct.statements).map { member ->
-                val targetDecl = member.first as VarDecl
-                val sourceDecl = member.second as VarDecl
-                if(targetDecl.name != sourceDecl.name)
-                    throw FatalAstException("struct member mismatch")
-                val mangled = mangledStructMemberName(identifierName, targetDecl.name)
-                val idref = IdentifierReference(listOf(mangled), structAssignment.position)
-                val sourcemangled = mangledStructMemberName(sourceVar.name, sourceDecl.name)
-                val sourceIdref = IdentifierReference(listOf(sourcemangled), structAssignment.position)
-                val assign = Assignment(AssignTarget(null, idref, null, null, structAssignment.position),
-                        null, sourceIdref, member.second.position)
-                assign.linkParents(structAssignment)
-                assign
-            }
-        }
-        structAssignment.value is StructLiteralValue -> {
-            throw IllegalArgumentException("not going to flatten a structLv assignment here")
-        }
-        else -> throw FatalAstException("strange struct value")
-    }
-}
-
-
-internal class StatementReorderer(private val program: Program): IAstModifyingVisitor {
+internal class StatementReorderer(val program: Program) : AstWalker() {
     // Reorders the statements in a way the compiler needs.
     // - 'main' block must be the very first statement UNLESS it has an address set.
-    // - blocks are ordered by address, where blocks without address are put at the end.
-    // - in every scope:
-    //      -- the directives '%output', '%launcher', '%zeropage', '%zpreserved', '%address' and '%option' will come first.
-    //      -- all vardecls then follow.
-    //      -- the remaining statements then follow in their original order.
-    //
-    // - the 'start' subroutine in the 'main' block will be moved to the top immediately following the directives.
-    // - all other subroutines will be moved to the end of their block.
+    // - library blocks are put last.
+    // - blocks are ordered by address, where blocks without address are placed last.
+    // - in every scope, most directives and vardecls are moved to the top.
+    // - the 'start' subroutine is moved to the top.
+    // - (syntax desugaring) a vardecl with a non-const initializer value is split into a regular vardecl and an assignment statement.
+    // - (syntax desugaring) struct value assignment is expanded into several struct member assignments.
+    // - in-place assignments are reordered a bit so that they are mostly of the form A = A <operator> <rest>
     // - sorts the choices in when statement.
-    //
-    // Also, makes sure any value assignments get the proper type casts if needed to cast them into the target variable's type.
-    // (this includes function call arguments)
+    // - insert AddressOf (&) expression where required (string params to a UWORD function param etc).
 
+    private val noModifications = emptyList<IAstModification>()
     private val directivesToMove = setOf("%output", "%launcher", "%zeropage", "%zpreserved", "%address", "%option")
 
-    override fun visit(module: Module) {
-        super.visit(module)
-
+    override fun after(module: Module, parent: Node): Iterable<IAstModification> {
         val (blocks, other) = module.statements.partition { it is Block }
         module.statements = other.asSequence().plus(blocks.sortedBy { (it as Block).address ?: Int.MAX_VALUE }).toMutableList()
 
-        // make sure user-defined blocks come BEFORE library blocks, and move the "main" block to the top of everything
-        val nonLibraryBlocks = module.statements.withIndex()
-                .filter { it.value is Block && !(it.value as Block).isInLibrary }
-                .map { it.index to it.value }
-                .reversed()
-        for(nonLibBlock in nonLibraryBlocks)
-            module.statements.removeAt(nonLibBlock.first)
-        for(nonLibBlock in nonLibraryBlocks)
-            module.statements.add(0, nonLibBlock.second)
-        val mainBlock = module.statements.singleOrNull { it is Block && it.name=="main" }
-        if(mainBlock!=null && (mainBlock as Block).address==null) {
-            module.remove(mainBlock)
+        val mainBlock = module.statements.filterIsInstance<Block>().firstOrNull { it.name=="main" }
+        if(mainBlock!=null && mainBlock.address==null) {
+            module.statements.remove(mainBlock)
             module.statements.add(0, mainBlock)
         }
 
-        val varDecls = module.statements.filterIsInstance<VarDecl>()
-        module.statements.removeAll(varDecls)
-        module.statements.addAll(0, varDecls)
-
-        val directives = module.statements.filter {it is Directive && it.directive in directivesToMove}
-        module.statements.removeAll(directives)
-        module.statements.addAll(0, directives)
+        reorderVardeclsAndDirectives(module.statements)
+        return noModifications
     }
 
-    override fun visit(block: Block): Statement {
+    private fun reorderVardeclsAndDirectives(statements: MutableList<Statement>) {
+        val varDecls = statements.filterIsInstance<VarDecl>()
+        statements.removeAll(varDecls)
+        statements.addAll(0, varDecls)
 
-        val subroutines = block.statements.filterIsInstance<Subroutine>()
-        var numSubroutinesAtEnd = 0
-        // move all subroutines to the end of the block
-        for (subroutine in subroutines) {
-            if(subroutine.name!="start" || block.name!="main") {
-                block.remove(subroutine)
-                block.statements.add(subroutine)
-            }
-            numSubroutinesAtEnd++
-        }
-        // move the "start" subroutine to the top
-        if(block.name=="main") {
-            block.statements.singleOrNull { it is Subroutine && it.name == "start" } ?.let {
-                block.remove(it)
-                block.statements.add(0, it)
-                numSubroutinesAtEnd--
-            }
-        }
-
-        // make sure there is a 'return' in front of the first subroutine
-        // (if it isn't the first statement in the block itself, and isn't the program's entrypoint)
-        if(numSubroutinesAtEnd>0 && block.statements.size > (numSubroutinesAtEnd+1)) {
-            val firstSub = block.statements[block.statements.size - numSubroutinesAtEnd] as Subroutine
-            if(firstSub.name != "start" && block.name != "main") {
-                val stmtBeforeFirstSub = block.statements[block.statements.size - numSubroutinesAtEnd - 1]
-                if (stmtBeforeFirstSub !is Return
-                        && stmtBeforeFirstSub !is Jump
-                        && stmtBeforeFirstSub !is Subroutine
-                        && stmtBeforeFirstSub !is BuiltinFunctionStatementPlaceholder) {
-                    val ret = Return(null, stmtBeforeFirstSub.position)
-                    ret.linkParents(block)
-                    block.statements.add(block.statements.size - numSubroutinesAtEnd, ret)
-                }
-            }
-        }
-
-        val varDecls = block.statements.filterIsInstance<VarDecl>()
-        block.statements.removeAll(varDecls)
-        block.statements.addAll(0, varDecls)
-        val directives = block.statements.filter {it is Directive && it.directive in directivesToMove}
-        block.statements.removeAll(directives)
-        block.statements.addAll(0, directives)
-        block.linkParents(block.parent)
-
-        // create subroutine that initializes the block's variables (if any)
-        val varInits = block.statements.withIndex().filter { it.value is VariableInitializationAssignment }
-        if(varInits.isNotEmpty()) {
-            val statements = varInits.map{it.value}.toMutableList()
-            val varInitSub = Subroutine(initvarsSubName, emptyList(), emptyList(), emptyList(), emptyList(),
-                    emptySet(), null, false, statements, block.position)
-            varInitSub.keepAlways = true
-            varInitSub.linkParents(block)
-            block.statements.add(varInitSub)
-
-            // remove the varinits from the block's statements
-            for(index in varInits.map{it.index}.reversed())
-                block.statements.removeAt(index)
-        }
-
-        return super.visit(block)
+        val directives = statements.filterIsInstance<Directive>().filter {it.directive in directivesToMove}
+        statements.removeAll(directives)
+        statements.addAll(0, directives)
     }
 
-    override fun visit(subroutine: Subroutine): Statement {
-        super.visit(subroutine)
-
-        val varDecls = subroutine.statements.filterIsInstance<VarDecl>()
-        subroutine.statements.removeAll(varDecls)
-        subroutine.statements.addAll(0, varDecls)
-        val directives = subroutine.statements.filter {it is Directive && it.directive in directivesToMove}
-        subroutine.statements.removeAll(directives)
-        subroutine.statements.addAll(0, directives)
-
-        if(subroutine.returntypes.isEmpty()) {
-            // add the implicit return statement at the end (if it's not there yet), but only if it's not a kernel routine.
-            // and if an assembly block doesn't contain a rts/rti
-            if(subroutine.asmAddress==null && subroutine.amountOfRtsInAsm()==0) {
-                if (subroutine.statements.lastOrNull {it !is VarDecl } !is Return) {
-                    val returnStmt = Return(null, subroutine.position)
-                    returnStmt.linkParents(subroutine)
-                    subroutine.statements.add(returnStmt)
-                }
-            }
+    override fun before(block: Block, parent: Node): Iterable<IAstModification> {
+        parent as Module
+        if(block.isInLibrary) {
+            return listOf(
+                    IAstModification.Remove(block, parent),
+                    IAstModification.InsertLast(block, parent)
+            )
         }
 
-        return subroutine
+        reorderVardeclsAndDirectives(block.statements)
+        return noModifications
     }
 
-    override fun visit(expr: BinaryExpression): Expression {
-        val expr2 = super.visit(expr)
-        if(expr2 !is BinaryExpression)
-            return expr2
-        val leftDt = expr2.left.inferType(program)
-        val rightDt = expr2.right.inferType(program)
-        if(leftDt!=null && rightDt!=null && leftDt!=rightDt) {
-            // determine common datatype and add typecast as required to make left and right equal types
-            val (commonDt, toFix) = BinaryExpression.commonDatatype(leftDt, rightDt, expr2.left, expr2.right)
-            if(toFix!=null) {
-                when {
-                    toFix===expr2.left -> {
-                        expr2.left = TypecastExpression(expr2.left, commonDt, true, expr2.left.position)
-                        expr2.left.linkParents(expr2)
-                    }
-                    toFix===expr2.right -> {
-                        expr2.right = TypecastExpression(expr2.right, commonDt, true, expr2.right.position)
-                        expr2.right.linkParents(expr2)
-                    }
-                    else -> throw FatalAstException("confused binary expression side")
-                }
+    override fun before(subroutine: Subroutine, parent: Node): Iterable<IAstModification> {
+        if(subroutine.name=="start" && parent is Block) {
+            if(parent.statements.filterIsInstance<Subroutine>().first().name!="start") {
+                return listOf(
+                        IAstModification.Remove(subroutine, parent),
+                        IAstModification.InsertFirst(subroutine, parent)
+                )
             }
         }
-        return expr2
+        return noModifications
     }
 
-    override fun visit(assignment: Assignment): Statement {
-        val assg = super.visit(assignment)
-        if(assg !is Assignment)
-            return assg
-
-        // see if a typecast is needed to convert the value's type into the proper target type
-        val valuetype = assg.value.inferType(program)
-        val targettype = assg.target.inferType(program, assg)
-        if(targettype!=null && valuetype!=null) {
-            if(valuetype!=targettype) {
-                if (valuetype isAssignableTo targettype) {
-                    assg.value = TypecastExpression(assg.value, targettype, true, assg.value.position)
-                    assg.value.linkParents(assg)
-                }
-                // if they're not assignable, we'll get a proper error later from the AstChecker
+    override fun after(decl: VarDecl, parent: Node): Iterable<IAstModification> {
+        val declValue = decl.value
+        if(declValue!=null && decl.type== VarDeclType.VAR && decl.datatype in NumericDatatypes) {
+            val declConstValue = declValue.constValue(program)
+            if(declConstValue==null) {
+                // move the vardecl (without value) to the scope and replace this with a regular assignment
+                decl.value = null
+                val target = AssignTarget(IdentifierReference(listOf(decl.name), decl.position), null, null, decl.position)
+                val assign = Assignment(target, declValue, decl.position)
+                return listOf(
+                        IAstModification.ReplaceNode(decl, assign, parent),
+                        IAstModification.InsertFirst(decl, decl.definingScope() as Node)
+                )
             }
         }
+        return noModifications
+    }
 
-        // struct assignments will be flattened (if it's not a struct literal)
-        if(valuetype==DataType.STRUCT && targettype==DataType.STRUCT) {
-            if(assg.value is StructLiteralValue)
-                return assg  // do NOT flatten it at this point!! (the compiler will take care if it, later, if needed)
+    override fun after(whenStatement: WhenStatement, parent: Node): Iterable<IAstModification> {
+        val choices = whenStatement.choiceValues(program).sortedBy {
+            it.first?.first() ?: Int.MAX_VALUE
+        }
+        whenStatement.choices.clear()
+        choices.mapTo(whenStatement.choices) { it.second }
+        return noModifications
+    }
 
-            val assignments = flattenStructAssignmentFromIdentifier(assg, program)    //   'structvar1 = structvar2'
-            return if(assignments.isEmpty()) {
-                // something went wrong (probably incompatible struct types)
-                // we'll get an error later from the AstChecker
-                assg
+    override fun before(assignment: Assignment, parent: Node): Iterable<IAstModification> {
+        val valueType = assignment.value.inferType(program)
+        val targetType = assignment.target.inferType(program, assignment)
+        if(valueType.istype(DataType.STRUCT) && targetType.istype(DataType.STRUCT)) {
+            val assignments = if (assignment.value is ArrayLiteralValue) {
+                flattenStructAssignmentFromStructLiteral(assignment, program)    //  'structvar = [ ..... ] '
             } else {
-                val scope = AnonymousScope(assignments.toMutableList(), assg.position)
-                scope.linkParents(assg.parent)
-                scope
+                flattenStructAssignmentFromIdentifier(assignment, program)    //   'structvar1 = structvar2'
+            }
+            if(assignments.isNotEmpty()) {
+                val modifications = mutableListOf<IAstModification>()
+                assignments.reversed().mapTo(modifications) { IAstModification.InsertAfter(assignment, it, parent) }
+                modifications.add(IAstModification.Remove(assignment, parent))
+                return modifications
             }
         }
 
-        if(assg.aug_op!=null) {
-            // transform augmented assg into normal assg so we have one case less to deal with later
-            val newTarget: Expression =
-                    when {
-                        assg.target.register != null -> RegisterExpr(assg.target.register!!, assg.target.position)
-                        assg.target.identifier != null -> assg.target.identifier!!
-                        assg.target.arrayindexed != null -> assg.target.arrayindexed!!
-                        assg.target.memoryAddress != null -> DirectMemoryRead(assg.target.memoryAddress!!.addressExpression, assg.value.position)
-                        else -> throw FatalAstException("strange assg")
-                    }
-
-            val expression = BinaryExpression(newTarget, assg.aug_op.substringBeforeLast('='), assg.value, assg.position)
-            expression.linkParents(assg.parent)
-            val convertedAssignment = Assignment(assg.target, null, expression, assg.position)
-            convertedAssignment.linkParents(assg.parent)
-            return super.visit(convertedAssignment)
-        }
-
-        return assg
+        return noModifications
     }
 
-    override fun visit(functionCallStatement: FunctionCallStatement): Statement {
-        checkFunctionCallArguments(functionCallStatement, functionCallStatement.definingScope())
-        return super.visit(functionCallStatement)
-    }
+    override fun after(assignment: Assignment, parent: Node): Iterable<IAstModification> {
+        // rewrite in-place assignment expressions a bit so that the assignment target usually is the leftmost operand
+        val binExpr = assignment.value as? BinaryExpression
+        if(binExpr!=null) {
+            if(binExpr.left isSameAs assignment.target) {
+                // A = A <operator> 5, unchanged
+                return noModifications
+            }
 
-    override fun visit(functionCall: FunctionCall): Expression {
-        checkFunctionCallArguments(functionCall, functionCall.definingScope())
-        return super.visit(functionCall)
-    }
+            if(binExpr.operator in associativeOperators) {
+                if (binExpr.right isSameAs assignment.target) {
+                    // A = v <associative-operator> A  ==>  A = A <associative-operator> v
+                    return listOf(IAstModification.SwapOperands(binExpr))
+                }
 
-    private fun checkFunctionCallArguments(call: IFunctionCall, scope: INameScope) {
-        // see if a typecast is needed to convert the arguments into the required parameter's type
-        when(val sub = call.target.targetStatement(scope)) {
-            is Subroutine -> {
-                for(arg in sub.parameters.zip(call.arglist.withIndex())) {
-                    val argtype = arg.second.value.inferType(program)
-                    if(argtype!=null) {
-                        val requiredType = arg.first.type
-                        if (requiredType != argtype) {
-                            if (argtype isAssignableTo requiredType) {
-                                val typecasted = TypecastExpression(arg.second.value, requiredType, true, arg.second.value.position)
-                                typecasted.linkParents(arg.second.value.parent)
-                                call.arglist[arg.second.index] = typecasted
-                            }
-                            // if they're not assignable, we'll get a proper error later from the AstChecker
-                        }
+                val leftBinExpr = binExpr.left as? BinaryExpression
+                if(leftBinExpr?.operator == binExpr.operator) {
+                    return if(leftBinExpr.left isSameAs assignment.target) {
+                        // A = (A <associative-operator> x) <same-operator> y ==> A = A <associative-operator> (x <same-operator> y)
+                        val newRight = BinaryExpression(leftBinExpr.right, binExpr.operator, binExpr.right, binExpr.position)
+                        val newValue = BinaryExpression(leftBinExpr.left, binExpr.operator, newRight, binExpr.position)
+                        listOf(IAstModification.ReplaceNode(binExpr, newValue, assignment))
+                    } else {
+                        // A = (x <associative-operator> A) <same-operator> y ==> A = A <associative-operator> (x <same-operator> y)
+                        val newRight = BinaryExpression(leftBinExpr.left, binExpr.operator, binExpr.right, binExpr.position)
+                        val newValue = BinaryExpression(leftBinExpr.right, binExpr.operator, newRight, binExpr.position)
+                        listOf(IAstModification.ReplaceNode(binExpr, newValue, assignment))
                     }
                 }
-            }
-            is BuiltinFunctionStatementPlaceholder -> {
-                val func = BuiltinFunctions.getValue(sub.name)
-                if(func.pure) {
-                    // non-pure functions don't get automatic typecasts because sometimes they act directly on their parameters
-                    for (arg in func.parameters.zip(call.arglist.withIndex())) {
-                        val argtype = arg.second.value.inferType(program)
-                        if (argtype != null) {
-                            if (arg.first.possibleDatatypes.any { argtype == it })
-                                continue
-                            for (possibleType in arg.first.possibleDatatypes) {
-                                if (argtype isAssignableTo possibleType) {
-                                    val typecasted = TypecastExpression(arg.second.value, possibleType, true, arg.second.value.position)
-                                    typecasted.linkParents(arg.second.value.parent)
-                                    call.arglist[arg.second.index] = typecasted
-                                    break
-                                }
-                            }
-                        }
-                    }
-                }
-            }
-            null -> {}
-            else -> TODO("call to something weird $sub   ${call.target}")
-        }
-    }
-
-    override fun visit(typecast: TypecastExpression): Expression {
-        // warn about any implicit type casts to Float, because that may not be intended
-        if(typecast.implicit && typecast.type in setOf(DataType.FLOAT, DataType.ARRAY_F)) {
-            printWarning("byte or word value implicitly converted to float. Suggestion: use explicit cast as float, a float number, or revert to integer arithmetic", typecast.position)
-        }
-        return super.visit(typecast)
-    }
-
-    override fun visit(memread: DirectMemoryRead): Expression {
-        // make sure the memory address is an uword
-        val dt = memread.addressExpression.inferType(program)
-        if(dt!=DataType.UWORD) {
-            val literaladdr = memread.addressExpression as? NumericLiteralValue
-            if(literaladdr!=null) {
-                memread.addressExpression = literaladdr.cast(DataType.UWORD)!!
-            } else {
-                memread.addressExpression = TypecastExpression(memread.addressExpression, DataType.UWORD, true, memread.addressExpression.position)
-                memread.addressExpression.parent = memread
-            }
-        }
-        return super.visit(memread)
-    }
-
-    override fun visit(memwrite: DirectMemoryWrite) {
-        val dt = memwrite.addressExpression.inferType(program)
-        if(dt!=DataType.UWORD) {
-            val literaladdr = memwrite.addressExpression as? NumericLiteralValue
-            if(literaladdr!=null) {
-                memwrite.addressExpression = literaladdr.cast(DataType.UWORD)!!
-            } else {
-                memwrite.addressExpression = TypecastExpression(memwrite.addressExpression, DataType.UWORD, true, memwrite.addressExpression.position)
-                memwrite.addressExpression.parent = memwrite
-            }
-        }
-        super.visit(memwrite)
-    }
-
-    override fun visit(structLv: StructLiteralValue): Expression {
-        val litval = super.visit(structLv)
-        if(litval !is StructLiteralValue)
-            return litval
-
-        val decl = litval.parent as? VarDecl
-        if(decl != null) {
-            val struct = decl.struct
-            if(struct != null) {
-                addTypecastsIfNeeded(litval, struct)
-            }
-        } else {
-            val assign = litval.parent as? Assignment
-            if (assign != null) {
-                val decl2 = assign.target.identifier?.targetVarDecl(program.namespace)
-                if(decl2 != null) {
-                    val struct = decl2.struct
-                    if(struct != null) {
-                        addTypecastsIfNeeded(litval, struct)
+                val rightBinExpr = binExpr.right as? BinaryExpression
+                if(rightBinExpr?.operator == binExpr.operator) {
+                    return if(rightBinExpr.left isSameAs assignment.target) {
+                        // A = x <associative-operator> (A <same-operator> y) ==> A = A <associative-operator> (x <same-operator> y)
+                        val newRight = BinaryExpression(binExpr.left, binExpr.operator, rightBinExpr.right, binExpr.position)
+                        val newValue = BinaryExpression(rightBinExpr.left, binExpr.operator, newRight, binExpr.position)
+                        listOf(IAstModification.ReplaceNode(binExpr, newValue, assignment))
+                    } else {
+                        // A = x <associative-operator> (y <same-operator> A) ==> A = A <associative-operator> (x <same-operator> y)
+                        val newRight = BinaryExpression(binExpr.left, binExpr.operator, rightBinExpr.left, binExpr.position)
+                        val newValue = BinaryExpression(rightBinExpr.right, binExpr.operator, newRight, binExpr.position)
+                        listOf(IAstModification.ReplaceNode(binExpr, newValue, assignment))
                     }
                 }
             }
         }
 
-        return litval
+        return noModifications
     }
 
-    private fun addTypecastsIfNeeded(structLv: StructLiteralValue, struct: StructDecl) {
-        structLv.values = struct.statements.zip(structLv.values).map {
-            val memberDt = (it.first as VarDecl).datatype
-            val valueDt = it.second.inferType(program)
-            if (valueDt != memberDt)
-                TypecastExpression(it.second, memberDt, true, it.second.position)
-            else
-                it.second
+    private fun flattenStructAssignmentFromStructLiteral(structAssignment: Assignment, program: Program): List<Assignment> {
+        val identifier = structAssignment.target.identifier!!
+        val identifierName = identifier.nameInSource.single()
+        val targetVar = identifier.targetVarDecl(program.namespace)!!
+        val struct = targetVar.struct!!
+
+        val slv = structAssignment.value as? ArrayLiteralValue
+        if(slv==null || slv.value.size != struct.numberOfElements)
+            throw FatalAstException("element count mismatch")
+
+        return struct.statements.zip(slv.value).map { (targetDecl, sourceValue) ->
+            targetDecl as VarDecl
+            val mangled = mangledStructMemberName(identifierName, targetDecl.name)
+            val idref = IdentifierReference(listOf(mangled), structAssignment.position)
+            val assign = Assignment(AssignTarget(idref, null, null, structAssignment.position),
+                    sourceValue, sourceValue.position)
+            assign.linkParents(structAssignment)
+            assign
         }
     }
+
+    private fun flattenStructAssignmentFromIdentifier(structAssignment: Assignment, program: Program): List<Assignment> {
+        val identifier = structAssignment.target.identifier!!
+        val identifierName = identifier.nameInSource.single()
+        val targetVar = identifier.targetVarDecl(program.namespace)!!
+        val struct = targetVar.struct!!
+        when (structAssignment.value) {
+            is IdentifierReference -> {
+                val sourceVar = (structAssignment.value as IdentifierReference).targetVarDecl(program.namespace)!!
+                if (sourceVar.struct == null)
+                    throw FatalAstException("can only assign arrays or structs to structs")
+                // struct memberwise copy
+                val sourceStruct = sourceVar.struct!!
+                if(sourceStruct!==targetVar.struct) {
+                    // structs are not the same in assignment
+                    return listOf()     // error will be printed elsewhere
+                }
+                return struct.statements.zip(sourceStruct.statements).map { member ->
+                    val targetDecl = member.first as VarDecl
+                    val sourceDecl = member.second as VarDecl
+                    if(targetDecl.name != sourceDecl.name)
+                        throw FatalAstException("struct member mismatch")
+                    val mangled = mangledStructMemberName(identifierName, targetDecl.name)
+                    val idref = IdentifierReference(listOf(mangled), structAssignment.position)
+                    val sourcemangled = mangledStructMemberName(sourceVar.name, sourceDecl.name)
+                    val sourceIdref = IdentifierReference(listOf(sourcemangled), structAssignment.position)
+                    val assign = Assignment(AssignTarget(idref, null, null, structAssignment.position), sourceIdref, member.second.position)
+                    assign.linkParents(structAssignment)
+                    assign
+                }
+            }
+            is ArrayLiteralValue -> {
+                throw IllegalArgumentException("not going to flatten a structLv assignment here")
+            }
+            else -> throw FatalAstException("strange struct value")
+        }
+    }
+
 }

compiler/src/prog8/ast/processing/TypecastsAdder.kt

@@ -0,0 +1,203 @@
+package prog8.ast.processing
+
+import prog8.ast.IFunctionCall
+import prog8.ast.INameScope
+import prog8.ast.Node
+import prog8.ast.Program
+import prog8.ast.base.*
+import prog8.ast.expressions.*
+import prog8.ast.statements.*
+import prog8.functions.BuiltinFunctions
+
+
+class TypecastsAdder(val program: Program, val errors: ErrorReporter) : AstWalker() {
+    /*
+     * Make sure any value assignments get the proper type casts if needed to cast them into the target variable's type.
+     * (this includes function call arguments)
+     */
+
+    private val noModifications = emptyList<IAstModification>()
+
+    override fun after(expr: BinaryExpression, parent: Node): Iterable<IAstModification> {
+        val leftDt = expr.left.inferType(program)
+        val rightDt = expr.right.inferType(program)
+        if(leftDt.isKnown && rightDt.isKnown && leftDt!=rightDt) {
+            // determine common datatype and add typecast as required to make left and right equal types
+            val (commonDt, toFix) = BinaryExpression.commonDatatype(leftDt.typeOrElse(DataType.STRUCT), rightDt.typeOrElse(DataType.STRUCT), expr.left, expr.right)
+            if(toFix!=null) {
+                return when {
+                    toFix===expr.left -> listOf(IAstModification.ReplaceNode(
+                            expr.left, TypecastExpression(expr.left, commonDt, true, expr.left.position), expr))
+                    toFix===expr.right -> listOf(IAstModification.ReplaceNode(
+                            expr.right, TypecastExpression(expr.right, commonDt, true, expr.right.position), expr))
+                    else -> throw FatalAstException("confused binary expression side")
+                }
+            }
+        }
+        return noModifications
+    }
+
+    override fun after(assignment: Assignment, parent: Node): Iterable<IAstModification> {
+        // see if a typecast is needed to convert the value's type into the proper target type
+        val valueItype = assignment.value.inferType(program)
+        val targetItype = assignment.target.inferType(program, assignment)
+        if(targetItype.isKnown && valueItype.isKnown) {
+            val targettype = targetItype.typeOrElse(DataType.STRUCT)
+            val valuetype = valueItype.typeOrElse(DataType.STRUCT)
+            if (valuetype != targettype) {
+                if (valuetype isAssignableTo targettype) {
+                    return listOf(IAstModification.ReplaceNode(
+                            assignment.value,
+                            TypecastExpression(assignment.value, targettype, true, assignment.value.position),
+                            assignment))
+                } else {
+                    fun castLiteral(cvalue: NumericLiteralValue): List<IAstModification.ReplaceNode> =
+                        listOf(IAstModification.ReplaceNode(cvalue, cvalue.cast(targettype), cvalue.parent))
+                    val cvalue = assignment.value.constValue(program)
+                    if(cvalue!=null) {
+                        val number = cvalue.number.toDouble()
+                        // more complex comparisons if the type is different, but the constant value is compatible
+                        if (valuetype == DataType.BYTE && targettype == DataType.UBYTE) {
+                            if(number>0)
+                                return castLiteral(cvalue)
+                        } else if (valuetype == DataType.WORD && targettype == DataType.UWORD) {
+                            if(number>0)
+                                return castLiteral(cvalue)
+                        } else if (valuetype == DataType.UBYTE && targettype == DataType.BYTE) {
+                            if(number<0x80)
+                                return castLiteral(cvalue)
+                        } else if (valuetype == DataType.UWORD && targettype == DataType.WORD) {
+                            if(number<0x8000)
+                                return castLiteral(cvalue)
+                        }
+                    }
+                }
+            }
+        }
+        return noModifications
+    }
+
+    override fun after(functionCallStatement: FunctionCallStatement, parent: Node): Iterable<IAstModification> {
+        return afterFunctionCallArgs(functionCallStatement, functionCallStatement.definingScope())
+    }
+
+    override fun after(functionCall: FunctionCall, parent: Node): Iterable<IAstModification> {
+        return afterFunctionCallArgs(functionCall, functionCall.definingScope())
+    }
+
+    private fun afterFunctionCallArgs(call: IFunctionCall, scope: INameScope): Iterable<IAstModification> {
+        // see if a typecast is needed to convert the arguments into the required parameter's type
+        val modifications = mutableListOf<IAstModification>()
+
+        when(val sub = call.target.targetStatement(scope)) {
+            is Subroutine -> {
+                for(arg in sub.parameters.zip(call.args.withIndex())) {
+                    val argItype = arg.second.value.inferType(program)
+                    if(argItype.isKnown) {
+                        val argtype = argItype.typeOrElse(DataType.STRUCT)
+                        val requiredType = arg.first.type
+                        if (requiredType != argtype) {
+                            if (argtype isAssignableTo requiredType) {
+                                modifications += IAstModification.ReplaceNode(
+                                        call.args[arg.second.index],
+                                        TypecastExpression(arg.second.value, requiredType, true, arg.second.value.position),
+                                        call as Node)
+                            } else if(requiredType == DataType.UWORD && argtype in PassByReferenceDatatypes) {
+                                // we allow STR/ARRAY values in place of UWORD parameters. Take their address instead.
+                                modifications += IAstModification.ReplaceNode(
+                                        call.args[arg.second.index],
+                                        AddressOf(arg.second.value as IdentifierReference, arg.second.value.position),
+                                        call as Node)
+                            } else if(arg.second.value is NumericLiteralValue) {
+                                try {
+                                    val castedValue = (arg.second.value as NumericLiteralValue).cast(requiredType)
+                                    modifications += IAstModification.ReplaceNode(
+                                            call.args[arg.second.index],
+                                            castedValue,
+                                            call as Node)
+                                } catch (x: ExpressionError) {
+                                    // no cast possible
+                                }
+                            }
+                        }
+                    }
+                }
+            }
+            is BuiltinFunctionStatementPlaceholder -> {
+                val func = BuiltinFunctions.getValue(sub.name)
+                for (arg in func.parameters.zip(call.args.withIndex())) {
+                    val argItype = arg.second.value.inferType(program)
+                    if (argItype.isKnown) {
+                        val argtype = argItype.typeOrElse(DataType.STRUCT)
+                        if (arg.first.possibleDatatypes.any { argtype == it })
+                            continue
+                        for (possibleType in arg.first.possibleDatatypes) {
+                            if (argtype isAssignableTo possibleType) {
+                                modifications += IAstModification.ReplaceNode(
+                                        call.args[arg.second.index],
+                                        TypecastExpression(arg.second.value, possibleType, true, arg.second.value.position),
+                                        call as Node)
+                            }
+                        }
+                    }
+                }
+            }
+            null -> { }
+            else -> throw FatalAstException("call to something weird $sub   ${call.target}")
+        }
+
+        return modifications
+    }
+
+    override fun after(typecast: TypecastExpression, parent: Node): Iterable<IAstModification> {
+        // warn about any implicit type casts to Float, because that may not be intended
+        if(typecast.implicit && typecast.type in setOf(DataType.FLOAT, DataType.ARRAY_F)) {
+            errors.warn("byte or word value implicitly converted to float. Suggestion: use explicit cast as float, a float number, or revert to integer arithmetic", typecast.position)
+        }
+        return noModifications
+    }
+
+    override fun after(memread: DirectMemoryRead, parent: Node): Iterable<IAstModification> {
+        // make sure the memory address is an uword
+        val dt = memread.addressExpression.inferType(program)
+        if(dt.isKnown && dt.typeOrElse(DataType.UWORD)!=DataType.UWORD) {
+            val typecast = (memread.addressExpression as? NumericLiteralValue)?.cast(DataType.UWORD)
+                    ?: TypecastExpression(memread.addressExpression, DataType.UWORD, true, memread.addressExpression.position)
+            return listOf(IAstModification.ReplaceNode(memread.addressExpression, typecast, memread))
+        }
+        return noModifications
+    }
+
+    override fun after(memwrite: DirectMemoryWrite, parent: Node): Iterable<IAstModification> {
+        // make sure the memory address is an uword
+        val dt = memwrite.addressExpression.inferType(program)
+        if(dt.isKnown && dt.typeOrElse(DataType.UWORD)!=DataType.UWORD) {
+            val typecast = (memwrite.addressExpression as? NumericLiteralValue)?.cast(DataType.UWORD)
+                    ?: TypecastExpression(memwrite.addressExpression, DataType.UWORD, true, memwrite.addressExpression.position)
+            return listOf(IAstModification.ReplaceNode(memwrite.addressExpression, typecast, memwrite))
+        }
+        return noModifications
+    }
+
+    override fun after(returnStmt: Return, parent: Node): Iterable<IAstModification> {
+        // add a typecast to the return type if it doesn't match the subroutine's signature
+        val returnValue = returnStmt.value
+        if(returnValue!=null) {
+            val subroutine = returnStmt.definingSubroutine()!!
+            if(subroutine.returntypes.size==1) {
+                val subReturnType = subroutine.returntypes.first()
+                if (returnValue.inferType(program).istype(subReturnType))
+                    return noModifications
+                if (returnValue is NumericLiteralValue) {
+                    returnStmt.value = returnValue.cast(subroutine.returntypes.single())
+                } else {
+                    return listOf(IAstModification.ReplaceNode(
+                            returnValue,
+                            TypecastExpression(returnValue, subReturnType, true, returnValue.position),
+                            returnStmt))
+                }
+            }
+        }
+        return noModifications
+    }
+}

compiler/src/prog8/ast/processing/VarInitValueAndAddressOfCreator.kt

@@ -1,163 +0,0 @@
-package prog8.ast.processing
-
-import prog8.ast.INameScope
-import prog8.ast.Module
-import prog8.ast.Node
-import prog8.ast.Program
-import prog8.ast.base.*
-import prog8.ast.expressions.*
-import prog8.ast.statements.*
-import prog8.compiler.CompilerException
-import prog8.functions.BuiltinFunctions
-import prog8.functions.FunctionSignature
-
-
-internal class VarInitValueAndAddressOfCreator(private val program: Program): IAstModifyingVisitor {
-    // For VarDecls that declare an initialization value:
-    // Replace the vardecl with an assignment (to set the initial value),
-    // and add a new vardecl with the default constant value of that type (usually zero) to the scope.
-    // This makes sure the variables get reset to the intended value on a next run of the program.
-    // Variable decls without a value don't get this treatment, which means they retain the last
-    // value they had when restarting the program.
-    // This is done in a separate step because it interferes with the namespace lookup of symbols
-    // in other ast processors.
-
-    // Also takes care to insert AddressOf (&) expression where required (string params to a UWORD function param etc).
-
-    private val vardeclsToAdd = mutableMapOf<INameScope, MutableList<VarDecl>>()
-
-    override fun visit(module: Module) {
-        vardeclsToAdd.clear()
-        super.visit(module)
-        // add any new vardecls to the various scopes
-        for((where, decls) in vardeclsToAdd) {
-            where.statements.addAll(0, decls)
-            decls.forEach { it.linkParents(where as Node) }
-        }
-    }
-
-    override fun visit(decl: VarDecl): Statement {
-        super.visit(decl)
-
-        if(decl.isArray && decl.value==null) {
-            // array datatype without initialization value, add list of zeros
-            val arraysize = decl.arraysize!!.size()!!
-            val array = ReferenceLiteralValue(decl.datatype, null,
-                    Array(arraysize) { NumericLiteralValue.optimalInteger(0, decl.position) },
-                    null, decl.position)
-            array.addToHeap(program.heap)
-            decl.value = array
-        }
-
-        if(decl.type!= VarDeclType.VAR || decl.value==null)
-            return decl
-
-        if(decl.datatype in NumericDatatypes) {
-            val scope = decl.definingScope()
-            addVarDecl(scope, decl.asDefaultValueDecl(null))
-            val declvalue = decl.value!!
-            val value =
-                    if(declvalue is NumericLiteralValue) {
-                        val converted = declvalue.cast(decl.datatype)
-                        converted ?: declvalue
-                    }
-                    else
-                        declvalue
-            val identifierName = listOf(decl.name)    // this was: (scoped name) decl.scopedname.split(".")
-            return VariableInitializationAssignment(
-                    AssignTarget(null, IdentifierReference(identifierName, decl.position), null, null, decl.position),
-                    null,
-                    value,
-                    decl.position
-            )
-        }
-
-        return decl
-    }
-
-    override fun visit(functionCall: FunctionCall): Expression {
-        var parentStatement: Node = functionCall
-        while(parentStatement !is Statement)
-            parentStatement = parentStatement.parent
-        val targetStatement = functionCall.target.targetSubroutine(program.namespace)
-        if(targetStatement!=null) {
-            addAddressOfExprIfNeeded(targetStatement, functionCall.arglist, parentStatement)
-        } else {
-            val builtinFunc = BuiltinFunctions[functionCall.target.nameInSource.joinToString (".")]
-            if(builtinFunc!=null)
-                addAddressOfExprIfNeededForBuiltinFuncs(builtinFunc, functionCall.arglist, parentStatement)
-        }
-        return functionCall
-    }
-
-    override fun visit(functionCallStatement: FunctionCallStatement): Statement {
-        val targetStatement = functionCallStatement.target.targetSubroutine(program.namespace)
-        if(targetStatement!=null) {
-            addAddressOfExprIfNeeded(targetStatement, functionCallStatement.arglist, functionCallStatement)
-        } else {
-            val builtinFunc = BuiltinFunctions[functionCallStatement.target.nameInSource.joinToString (".")]
-            if(builtinFunc!=null)
-                addAddressOfExprIfNeededForBuiltinFuncs(builtinFunc, functionCallStatement.arglist, functionCallStatement)
-        }
-        return functionCallStatement
-    }
-
-    private fun addAddressOfExprIfNeeded(subroutine: Subroutine, arglist: MutableList<Expression>, parent: Statement) {
-        // functions that accept UWORD and are given an array type, or string, will receive the AddressOf (memory location) of that value instead.
-        for(argparam in subroutine.parameters.withIndex().zip(arglist)) {
-            if(argparam.first.value.type==DataType.UWORD || argparam.first.value.type in StringDatatypes) {
-                if(argparam.second is AddressOf)
-                    continue
-                val idref = argparam.second as? IdentifierReference
-                val strvalue = argparam.second as? ReferenceLiteralValue
-                if(idref!=null) {
-                    val variable = idref.targetVarDecl(program.namespace)
-                    if(variable!=null && (variable.datatype in StringDatatypes || variable.datatype in ArrayDatatypes)) {
-                        val pointerExpr = AddressOf(idref, idref.position)
-                        pointerExpr.scopedname = parent.makeScopedName(idref.nameInSource.single())
-                        pointerExpr.linkParents(arglist[argparam.first.index].parent)
-                        arglist[argparam.first.index] = pointerExpr
-                    }
-                }
-                else if(strvalue!=null) {
-                    if(strvalue.isString) {
-                        // add a vardecl so that the autovar can be resolved in later lookups
-                        val variable = VarDecl.createAuto(strvalue, program.heap)
-                        addVarDecl(strvalue.definingScope(), variable)
-                        // replace the argument with &autovar
-                        val autoHeapvarRef = IdentifierReference(listOf(variable.name), strvalue.position)
-                        val pointerExpr = AddressOf(autoHeapvarRef, strvalue.position)
-                        pointerExpr.scopedname = parent.makeScopedName(variable.name)
-                        pointerExpr.linkParents(arglist[argparam.first.index].parent)
-                        arglist[argparam.first.index] = pointerExpr
-                    }
-                }
-            }
-        }
-    }
-
-    private fun addAddressOfExprIfNeededForBuiltinFuncs(signature: FunctionSignature, args: MutableList<Expression>, parent: Statement) {
-        for(arg in args.withIndex().zip(signature.parameters)) {
-            val argvalue = arg.first.value
-            val argDt = argvalue.inferType(program)
-            if(DataType.UWORD in arg.second.possibleDatatypes && argDt in PassByReferenceDatatypes) {
-                if(argvalue !is IdentifierReference)
-                    throw CompilerException("pass-by-reference parameter isn't an identifier? $argvalue")
-                val addrOf = AddressOf(argvalue, argvalue.position)
-                args[arg.first.index] = addrOf
-                addrOf.scopedname = parent.makeScopedName(argvalue.nameInSource.single())
-                addrOf.linkParents(parent)
-            }
-        }
-    }
-
-
-    private fun addVarDecl(scope: INameScope, variable: VarDecl) {
-        if(scope !in vardeclsToAdd)
-            vardeclsToAdd[scope] = mutableListOf()
-        val declList = vardeclsToAdd.getValue(scope)
-        if(declList.all{it.name!=variable.name})
-            declList.add(variable)
-    }
-
-}

compiler/src/prog8/ast/processing/VariousCleanups.kt

@@ -0,0 +1,43 @@
+package prog8.ast.processing
+
+import prog8.ast.INameScope
+import prog8.ast.Node
+import prog8.ast.expressions.NumericLiteralValue
+import prog8.ast.expressions.TypecastExpression
+import prog8.ast.statements.AnonymousScope
+import prog8.ast.statements.NopStatement
+
+
+internal class VariousCleanups: AstWalker() {
+    private val noModifications = emptyList<IAstModification>()
+
+    override fun before(nopStatement: NopStatement, parent: Node): Iterable<IAstModification> {
+        return listOf(IAstModification.Remove(nopStatement, parent))
+    }
+
+    override fun before(scope: AnonymousScope, parent: Node): Iterable<IAstModification> {
+        return if(parent is INameScope)
+            listOf(ScopeFlatten(scope, parent as INameScope))
+        else
+            noModifications
+    }
+
+    class ScopeFlatten(val scope: AnonymousScope, val into: INameScope) : IAstModification {
+        override fun perform() {
+            val idx = into.statements.indexOf(scope)
+            if(idx>=0) {
+                into.statements.addAll(idx+1, scope.statements)
+                into.statements.remove(scope)
+            }
+        }
+    }
+
+    override fun before(typecast: TypecastExpression, parent: Node): Iterable<IAstModification> {
+        if(typecast.expression is NumericLiteralValue) {
+            val value = (typecast.expression as NumericLiteralValue).cast(typecast.type)
+            return listOf(IAstModification.ReplaceNode(typecast, value, parent))
+        }
+
+        return noModifications
+    }
+}

compiler/src/prog8/ast/processing/VerifyFunctionArgTypes.kt

@@ -0,0 +1,53 @@
+package prog8.ast.processing
+
+import prog8.ast.IFunctionCall
+import prog8.ast.INameScope
+import prog8.ast.Program
+import prog8.ast.base.DataType
+import prog8.ast.expressions.FunctionCall
+import prog8.ast.statements.BuiltinFunctionStatementPlaceholder
+import prog8.ast.statements.FunctionCallStatement
+import prog8.ast.statements.Subroutine
+import prog8.compiler.CompilerException
+import prog8.functions.BuiltinFunctions
+
+class VerifyFunctionArgTypes(val program: Program) : IAstVisitor {
+
+    override fun visit(functionCall: FunctionCall) {
+        val error = checkTypes(functionCall as IFunctionCall, functionCall.definingScope(), program)
+        if(error!=null)
+            throw CompilerException(error)
+    }
+
+    override fun visit(functionCallStatement: FunctionCallStatement) {
+        val error = checkTypes(functionCallStatement as IFunctionCall, functionCallStatement.definingScope(), program)
+        if (error!=null)
+            throw CompilerException(error)
+    }
+
+    companion object {
+        fun checkTypes(call: IFunctionCall, scope: INameScope, program: Program): String? {
+            val argtypes = call.args.map { it.inferType(program).typeOrElse(DataType.STRUCT) }
+            val target = call.target.targetStatement(scope)
+            when (target) {
+                is Subroutine -> {
+                    val paramtypes = target.parameters.map { it.type }
+                    val mismatch = argtypes.zip(paramtypes).indexOfFirst { it.first != it.second}
+                    if(mismatch>=0)
+                        return "argument ${mismatch+1} type mismatch"
+                }
+                is BuiltinFunctionStatementPlaceholder -> {
+                    val func = BuiltinFunctions.getValue(target.name)
+                    val paramtypes = func.parameters.map { it.possibleDatatypes }
+                    for (x in argtypes.zip(paramtypes).withIndex()) {
+                        if (x.value.first !in x.value.second)
+                            return "argument ${x.index+1} type mismatch"
+                    }
+                }
+                else -> {
+                }
+            }
+            return null
+        }
+    }
+}

compiler/src/prog8/ast/statements/AstStatements.kt

@@ -3,14 +3,14 @@ package prog8.ast.statements
 import prog8.ast.*
 import prog8.ast.base.*
 import prog8.ast.expressions.*
-import prog8.ast.processing.IAstModifyingVisitor
+import prog8.ast.processing.AstWalker
 import prog8.ast.processing.IAstVisitor
-import prog8.compiler.HeapValues
 
 
 sealed class Statement : Node {
-    abstract fun accept(visitor: IAstModifyingVisitor) : Statement
     abstract fun accept(visitor: IAstVisitor)
+    abstract fun accept(visitor: AstWalker, parent: Node)
+
     fun makeScopedName(name: String): String {
         // easy way out is to always return the full scoped name.
         // it would be nicer to find only the minimal prefixed scoped name, but that's too much hassle for now.
@@ -29,8 +29,6 @@ sealed class Statement : Node {
         return scope.joinToString(".")
     }
 
-    abstract val expensiveToInline: Boolean
-
     fun definingBlock(): Block {
         if(this is Block)
             return this
@@ -42,32 +40,37 @@ sealed class Statement : Node {
 class BuiltinFunctionStatementPlaceholder(val name: String, override val position: Position) : Statement() {
     override var parent: Node = ParentSentinel
     override fun linkParents(parent: Node) {}
-    override fun accept(visitor: IAstModifyingVisitor) = visitor.visit(this)
     override fun accept(visitor: IAstVisitor) = visitor.visit(this)
+    override fun accept(visitor: AstWalker, parent: Node) = visitor.visit(this, parent)
     override fun definingScope(): INameScope = BuiltinFunctionScopePlaceholder
-    override val expensiveToInline = false
+    override fun replaceChildNode(node: Node, replacement: Node) {
+        replacement.parent = this
+    }
 }
 
-
 data class RegisterOrStatusflag(val registerOrPair: RegisterOrPair?, val statusflag: Statusflag?, val stack: Boolean)
 
-
 class Block(override val name: String,
             val address: Int?,
             override var statements: MutableList<Statement>,
             val isInLibrary: Boolean,
             override val position: Position) : Statement(), INameScope {
     override lateinit var parent: Node
-    override val expensiveToInline
-        get() = statements.any { it.expensiveToInline }
 
     override fun linkParents(parent: Node) {
         this.parent = parent
         statements.forEach {it.linkParents(this)}
     }
 
-    override fun accept(visitor: IAstModifyingVisitor) = visitor.visit(this)
+    override fun replaceChildNode(node: Node, replacement: Node) {
+        require(replacement is Statement)
+        val idx = statements.indexOfFirst { it ===node }
+        statements[idx] = replacement
+        replacement.parent = this
+    }
+
     override fun accept(visitor: IAstVisitor) = visitor.visit(this)
+    override fun accept(visitor: AstWalker, parent: Node) = visitor.visit(this, parent)
 
     override fun toString(): String {
         return "Block(name=$name, address=$address, ${statements.size} statements)"
@@ -78,15 +81,15 @@ class Block(override val name: String,
 
 data class Directive(val directive: String, val args: List<DirectiveArg>, override val position: Position) : Statement() {
     override lateinit var parent: Node
-    override val expensiveToInline = false
 
     override fun linkParents(parent: Node) {
         this.parent = parent
         args.forEach{it.linkParents(this)}
     }
 
-    override fun accept(visitor: IAstModifyingVisitor) = visitor.visit(this)
+    override fun replaceChildNode(node: Node, replacement: Node) = throw FatalAstException("can't replace here")
     override fun accept(visitor: IAstVisitor) = visitor.visit(this)
+    override fun accept(visitor: AstWalker, parent: Node) = visitor.visit(this, parent)
 }
 
 data class DirectiveArg(val str: String?, val name: String?, val int: Int?, override val position: Position) : Node {
@@ -95,37 +98,41 @@ data class DirectiveArg(val str: String?, val name: String?, val int: Int?, over
     override fun linkParents(parent: Node) {
         this.parent = parent
     }
+    override fun replaceChildNode(node: Node, replacement: Node) = throw FatalAstException("can't replace here")
 }
 
 data class Label(val name: String, override val position: Position) : Statement() {
     override lateinit var parent: Node
-    override val expensiveToInline = false
 
     override fun linkParents(parent: Node) {
         this.parent = parent
     }
 
-    override fun accept(visitor: IAstModifyingVisitor) = visitor.visit(this)
+    override fun replaceChildNode(node: Node, replacement: Node) = throw FatalAstException("can't replace here")
     override fun accept(visitor: IAstVisitor) = visitor.visit(this)
+    override fun accept(visitor: AstWalker, parent: Node) = visitor.visit(this, parent)
 
     override fun toString(): String {
         return "Label(name=$name, pos=$position)"
     }
-
-    val scopedname: String by lazy { makeScopedName(name) }
 }
 
 open class Return(var value: Expression?, override val position: Position) : Statement() {
     override lateinit var parent: Node
-    override val expensiveToInline = value!=null && value !is NumericLiteralValue
 
     override fun linkParents(parent: Node) {
         this.parent = parent
         value?.linkParents(this)
     }
 
-    override fun accept(visitor: IAstModifyingVisitor) = visitor.visit(this)
+    override fun replaceChildNode(node: Node, replacement: Node) {
+        require(replacement is Expression)
+        value = replacement
+        replacement.parent = this
+    }
+
     override fun accept(visitor: IAstVisitor) = visitor.visit(this)
+    override fun accept(visitor: AstWalker, parent: Node) = visitor.visit(this, parent)
 
     override fun toString(): String {
         return "Return($value, pos=$position)"
@@ -133,36 +140,24 @@ open class Return(var value: Expression?, override val position: Position) : Sta
 }
 
 class ReturnFromIrq(override val position: Position) : Return(null, position) {
-    override fun accept(visitor: IAstModifyingVisitor) = visitor.visit(this)
     override fun accept(visitor: IAstVisitor) = visitor.visit(this)
 
     override fun toString(): String {
         return "ReturnFromIrq(pos=$position)"
     }
-}
-
-class Continue(override val position: Position) : Statement() {
-    override lateinit var parent: Node
-    override val expensiveToInline = false
-
-    override fun linkParents(parent: Node) {
-        this.parent=parent
-    }
-
-    override fun accept(visitor: IAstModifyingVisitor) = visitor.visit(this)
-    override fun accept(visitor: IAstVisitor) = visitor.visit(this)
+    override fun replaceChildNode(node: Node, replacement: Node) = throw FatalAstException("can't replace here")
 }
 
 class Break(override val position: Position) : Statement() {
     override lateinit var parent: Node
-    override val expensiveToInline = false
 
     override fun linkParents(parent: Node) {
         this.parent=parent
     }
 
-    override fun accept(visitor: IAstModifyingVisitor) = visitor.visit(this)
+    override fun replaceChildNode(node: Node, replacement: Node) = throw FatalAstException("can't replace here")
     override fun accept(visitor: IAstVisitor) = visitor.visit(this)
+    override fun accept(visitor: AstWalker, parent: Node) = visitor.visit(this, parent)
 }
 
 
@@ -173,7 +168,8 @@ enum class ZeropageWish {
     NOT_IN_ZEROPAGE
 }
 
-class VarDecl(val type: VarDeclType,
+
+open class VarDecl(val type: VarDeclType,
               private val declaredDatatype: DataType,
               val zeropage: ZeropageWish,
               var arraysize: ArrayIndex?,
@@ -189,28 +185,32 @@ class VarDecl(val type: VarDeclType,
     var structHasBeenFlattened = false      // set later
         private set
 
-    override val expensiveToInline
-            get() = value!=null && value !is NumericLiteralValue
-
     // prefix for literal values that are turned into a variable on the heap
 
     companion object {
         private var autoHeapValueSequenceNumber = 0
 
-        fun createAuto(refLv: ReferenceLiteralValue, heap: HeapValues): VarDecl {
-            if(refLv.heapId==null)
-                throw FatalAstException("can only create autovar for a ref lv that has a heapid  $refLv")
-
+        fun createAuto(string: StringLiteralValue): VarDecl {
             val autoVarName = "auto_heap_value_${++autoHeapValueSequenceNumber}"
-            return if(refLv.isArray) {
-                val declaredType = ArrayElementTypes.getValue(refLv.type)
-                val arraysize = ArrayIndex.forArray(refLv, heap)
-                VarDecl(VarDeclType.VAR, declaredType, ZeropageWish.NOT_IN_ZEROPAGE, arraysize, autoVarName, null, refLv,
-                        isArray = true, autogeneratedDontRemove = true, position = refLv.position)
-            } else {
-                VarDecl(VarDeclType.VAR, refLv.type, ZeropageWish.NOT_IN_ZEROPAGE, null, autoVarName, null, refLv,
-                        isArray = false, autogeneratedDontRemove = true, position = refLv.position)
-            }
+            return VarDecl(VarDeclType.VAR, DataType.STR, ZeropageWish.NOT_IN_ZEROPAGE, null, autoVarName, null, string,
+                        isArray = false, autogeneratedDontRemove = true, position = string.position)
+        }
+
+        fun createAuto(array: ArrayLiteralValue): VarDecl {
+            val autoVarName = "auto_heap_value_${++autoHeapValueSequenceNumber}"
+            val declaredType = ArrayElementTypes.getValue(array.type.typeOrElse(DataType.STRUCT))
+            val arraysize = ArrayIndex.forArray(array)
+            return VarDecl(VarDeclType.VAR, declaredType, ZeropageWish.NOT_IN_ZEROPAGE, arraysize, autoVarName, null, array,
+                    isArray = true, autogeneratedDontRemove = true, position = array.position)
+        }
+
+        fun defaultZero(dt: DataType, position: Position) = when(dt) {
+            DataType.UBYTE -> NumericLiteralValue(DataType.UBYTE, 0,  position)
+            DataType.BYTE -> NumericLiteralValue(DataType.BYTE, 0,  position)
+            DataType.UWORD -> NumericLiteralValue(DataType.UWORD, 0, position)
+            DataType.WORD -> NumericLiteralValue(DataType.WORD, 0, position)
+            DataType.FLOAT -> NumericLiteralValue(DataType.FLOAT, 0.0, position)
+            else -> throw FatalAstException("can only determine default zero value for a numeric type")
         }
     }
 
@@ -240,34 +240,25 @@ class VarDecl(val type: VarDeclType,
         }
     }
 
-    override fun accept(visitor: IAstModifyingVisitor) = visitor.visit(this)
-    override fun accept(visitor: IAstVisitor) = visitor.visit(this)
+    override fun replaceChildNode(node: Node, replacement: Node) {
+        require(replacement is Expression && node===value)
+        value = replacement
+        replacement.parent = this
+    }
 
-    val scopedname: String by lazy { makeScopedName(name) }
+    override fun accept(visitor: IAstVisitor) = visitor.visit(this)
+    override fun accept(visitor: AstWalker, parent: Node) = visitor.visit(this, parent)
 
     override fun toString(): String {
         return "VarDecl(name=$name, vartype=$type, datatype=$datatype, struct=$structName, value=$value, pos=$position)"
     }
 
-    fun asDefaultValueDecl(parent: Node?): VarDecl {
-        val constValue = when(declaredDatatype) {
-            DataType.UBYTE -> NumericLiteralValue(DataType.UBYTE, 0,  position)
-            DataType.BYTE -> NumericLiteralValue(DataType.BYTE, 0,  position)
-            DataType.UWORD -> NumericLiteralValue(DataType.UWORD, 0, position)
-            DataType.WORD -> NumericLiteralValue(DataType.WORD, 0, position)
-            DataType.FLOAT -> NumericLiteralValue(DataType.FLOAT, 0.0, position)
-            else -> throw FatalAstException("can only set a default value for a numeric type")
-        }
-        val decl = VarDecl(type, declaredDatatype, zeropage, arraysize, name, structName, constValue, isArray, false, position)
-        if(parent!=null)
-            decl.linkParents(parent)
-        return decl
-    }
+    fun zeroElementValue() = defaultZero(declaredDatatype, position)
 
     fun flattenStructMembers(): MutableList<Statement> {
         val result = struct!!.statements.withIndex().map {
             val member = it.value as VarDecl
-            val initvalue = if(value!=null) (value as StructLiteralValue).values[it.index] else null
+            val initvalue = if(value!=null) (value as ArrayLiteralValue).value[it.index] else null
             VarDecl(
                     VarDeclType.VAR,
                     member.datatype,
@@ -284,14 +275,13 @@ class VarDecl(val type: VarDeclType,
         structHasBeenFlattened = true
         return result
     }
-
-    fun withPrefixedName(nameprefix: String): Statement {
-        val new = VarDecl(type, declaredDatatype, zeropage, arraysize, nameprefix+name, structName, value, isArray, autogeneratedDontRemove, position)
-        new.parent = parent
-        return new
-    }
 }
 
+// a vardecl used only for subroutine parameters
+class ParameterVarDecl(name: String, declaredDatatype: DataType, position: Position)
+    : VarDecl(VarDeclType.VAR, declaredDatatype, ZeropageWish.NOT_IN_ZEROPAGE, null, name, null, null, false, true, position)
+
+
 class ArrayIndex(var index: Expression, override val position: Position) : Node {
     override lateinit var parent: Node
 
@@ -300,20 +290,20 @@ class ArrayIndex(var index: Expression, override val position: Position) : Node
         index.linkParents(this)
     }
 
+    override fun replaceChildNode(node: Node, replacement: Node) {
+        require(replacement is Expression && node===index)
+        index = replacement
+        replacement.parent = this
+    }
+
     companion object {
-        fun forArray(v: ReferenceLiteralValue, heap: HeapValues): ArrayIndex {
-            val arraySize = v.array?.size ?: heap.get(v.heapId!!).arraysize
-            return ArrayIndex(NumericLiteralValue.optimalNumeric(arraySize, v.position), v.position)
+        fun forArray(v: ArrayLiteralValue): ArrayIndex {
+            return ArrayIndex(NumericLiteralValue.optimalNumeric(v.value.size, v.position), v.position)
         }
     }
 
-    fun accept(visitor: IAstModifyingVisitor) {
-        index = index.accept(visitor)
-    }
-
-    fun accept(visitor: IAstVisitor) {
-        index.accept(visitor)
-    }
+    fun accept(visitor: IAstVisitor) = index.accept(visitor)
+    fun accept(visitor: AstWalker, parent: Node) = index.accept(visitor, this)
 
     override fun toString(): String {
         return("ArrayIndex($index, pos=$position)")
@@ -322,10 +312,8 @@ class ArrayIndex(var index: Expression, override val position: Position) : Node
     fun size() = (index as? NumericLiteralValue)?.number?.toInt()
 }
 
-open class Assignment(var target: AssignTarget, val aug_op : String?, var value: Expression, override val position: Position) : Statement() {
+open class Assignment(var target: AssignTarget, var value: Expression, override val position: Position) : Statement() {
     override lateinit var parent: Node
-    override val expensiveToInline
-            get() = value !is NumericLiteralValue
 
     override fun linkParents(parent: Node) {
         this.parent = parent
@@ -333,21 +321,53 @@ open class Assignment(var target: AssignTarget, val aug_op : String?, var value:
         value.linkParents(this)
     }
 
-    override fun accept(visitor: IAstModifyingVisitor) = visitor.visit(this)
+    override fun replaceChildNode(node: Node, replacement: Node) {
+        when {
+            node===target -> target = replacement as AssignTarget
+            node===value -> value = replacement as Expression
+            else -> throw FatalAstException("invalid replace")
+        }
+        replacement.parent = this
+    }
+
     override fun accept(visitor: IAstVisitor) = visitor.visit(this)
+    override fun accept(visitor: AstWalker, parent: Node) = visitor.visit(this, parent)
 
     override fun toString(): String {
-        return("Assignment(augop: $aug_op, target: $target, value: $value, pos=$position)")
+        return("Assignment(target: $target, value: $value, pos=$position)")
     }
+
+    val isInplace: Boolean
+        get() {
+            val binExpr = value as? BinaryExpression
+            if(binExpr!=null) {
+                if(binExpr.left isSameAs target)
+                    return true  // A = A <operator> 5
+
+                if(binExpr.operator in associativeOperators) {
+                    if (binExpr.right isSameAs target)
+                        return true  // A = v <associative-operator> A
+
+                    val leftBinExpr = binExpr.left as? BinaryExpression
+                    if(leftBinExpr?.operator == binExpr.operator) {
+                        // A = (A <associative-operator> x) <same-operator> y
+                        // A = (x <associative-operator> A) <same-operator> y
+                        return leftBinExpr.left isSameAs target || leftBinExpr.right isSameAs target
+                    }
+                    val rightBinExpr = binExpr.right as? BinaryExpression
+                    if(rightBinExpr?.operator == binExpr.operator) {
+                        // A = y <associative-operator> (A <same-operator> x)
+                        // A = y <associative-operator> (x <same-operator> y)
+                        return rightBinExpr.left isSameAs target || rightBinExpr.right isSameAs target
+                    }
+                }
+            }
+
+            return false
+        }
 }
 
-// This is a special class so the compiler can see if the assignments are for initializing the vars in the scope,
-// or just a regular assignment. It may optimize the initialization step from this.
-class VariableInitializationAssignment(target: AssignTarget, aug_op: String?, value: Expression, position: Position)
-    : Assignment(target, aug_op, value, position)
-
-data class AssignTarget(val register: Register?,
-                        var identifier: IdentifierReference?,
+data class AssignTarget(var identifier: IdentifierReference?,
                         var arrayindexed: ArrayIndexedExpression?,
                         val memoryAddress: DirectMemoryWrite?,
                         override val position: Position) : Node {
@@ -360,46 +380,63 @@ data class AssignTarget(val register: Register?,
         memoryAddress?.linkParents(this)
     }
 
-    fun accept(visitor: IAstModifyingVisitor) = visitor.visit(this)
+    override fun replaceChildNode(node: Node, replacement: Node) {
+        when {
+            node===identifier -> identifier = replacement as IdentifierReference
+            node===arrayindexed -> arrayindexed = replacement as ArrayIndexedExpression
+            else -> throw FatalAstException("invalid replace")
+        }
+        replacement.parent = this
+    }
+
     fun accept(visitor: IAstVisitor) = visitor.visit(this)
+    fun accept(visitor: AstWalker, parent: Node) = visitor.visit(this, parent)
 
     companion object {
         fun fromExpr(expr: Expression): AssignTarget {
             return when (expr) {
-                is RegisterExpr -> AssignTarget(expr.register, null, null, null, expr.position)
-                is IdentifierReference -> AssignTarget(null, expr, null, null, expr.position)
-                is ArrayIndexedExpression -> AssignTarget(null, null, expr, null, expr.position)
-                is DirectMemoryRead -> AssignTarget(null, null, null, DirectMemoryWrite(expr.addressExpression, expr.position), expr.position)
+                is IdentifierReference -> AssignTarget(expr, null, null, expr.position)
+                is ArrayIndexedExpression -> AssignTarget(null, expr, null, expr.position)
+                is DirectMemoryRead -> AssignTarget(null, null, DirectMemoryWrite(expr.addressExpression, expr.position), expr.position)
                 else -> throw FatalAstException("invalid expression object $expr")
             }
         }
     }
 
-    fun inferType(program: Program, stmt: Statement): DataType? {
-        if(register!=null)
-            return DataType.UBYTE
-
+    fun inferType(program: Program, stmt: Statement): InferredTypes.InferredType {
         if(identifier!=null) {
-            val symbol = program.namespace.lookup(identifier!!.nameInSource, stmt) ?: return null
-            if (symbol is VarDecl) return symbol.datatype
+            val symbol = program.namespace.lookup(identifier!!.nameInSource, stmt) ?: return InferredTypes.unknown()
+            if (symbol is VarDecl) return InferredTypes.knownFor(symbol.datatype)
         }
 
         if(arrayindexed!=null) {
-            val dt = arrayindexed!!.inferType(program)
-            if(dt!=null)
-                return dt
+            return arrayindexed!!.inferType(program)
         }
 
         if(memoryAddress!=null)
-            return DataType.UBYTE
+            return InferredTypes.knownFor(DataType.UBYTE)
 
-        return null
+        return InferredTypes.unknown()
+    }
+
+    fun toExpression(): Expression {
+        return when {
+            identifier!=null -> identifier!!
+            arrayindexed!=null -> arrayindexed!!
+            memoryAddress!=null -> DirectMemoryRead(memoryAddress.addressExpression, memoryAddress.position)
+            else -> throw FatalAstException("invalid assignmenttarget $this")
+        }
     }
 
     infix fun isSameAs(value: Expression): Boolean {
         return when {
-            this.memoryAddress!=null -> false
-            this.register!=null -> value is RegisterExpr && value.register==register
+            this.memoryAddress!=null -> {
+                // if the target is a memory write, and the value is a memory read, they're the same if the address matches
+                if(value is DirectMemoryRead)
+                    this.memoryAddress.addressExpression isSameAs value.addressExpression
+                else
+                    false
+            }
             this.identifier!=null -> value is IdentifierReference && value.nameInSource==identifier!!.nameInSource
             this.arrayindexed!=null -> value is ArrayIndexedExpression &&
                     value.identifier.nameInSource==arrayindexed!!.identifier.nameInSource &&
@@ -413,8 +450,6 @@ data class AssignTarget(val register: Register?,
     fun isSameAs(other: AssignTarget, program: Program): Boolean {
         if(this===other)
             return true
-        if(this.register!=null && other.register!=null)
-            return this.register==other.register
         if(this.identifier!=null && other.identifier!=null)
             return this.identifier!!.nameInSource==other.identifier!!.nameInSource
         if(this.memoryAddress!=null && other.memoryAddress!=null) {
@@ -433,8 +468,6 @@ data class AssignTarget(val register: Register?,
     }
 
     fun isNotMemory(namespace: INameScope): Boolean {
-        if(this.register!=null)
-            return true
         if(this.memoryAddress!=null)
             return false
         if(this.arrayindexed!=null) {
@@ -453,15 +486,20 @@ data class AssignTarget(val register: Register?,
 
 class PostIncrDecr(var target: AssignTarget, val operator: String, override val position: Position) : Statement() {
     override lateinit var parent: Node
-    override val expensiveToInline = false
 
     override fun linkParents(parent: Node) {
         this.parent = parent
         target.linkParents(this)
     }
 
-    override fun accept(visitor: IAstModifyingVisitor) = visitor.visit(this)
+    override fun replaceChildNode(node: Node, replacement: Node) {
+        require(replacement is AssignTarget && node===target)
+        target = replacement
+        replacement.parent = this
+    }
+
     override fun accept(visitor: IAstVisitor) = visitor.visit(this)
+    override fun accept(visitor: AstWalker, parent: Node) = visitor.visit(this, parent)
 
     override fun toString(): String {
         return "PostIncrDecr(op: $operator, target: $target, pos=$position)"
@@ -473,15 +511,15 @@ class Jump(val address: Int?,
            val generatedLabel: String?,             // used in code generation scenarios
            override val position: Position) : Statement() {
     override lateinit var parent: Node
-    override val expensiveToInline = false
 
     override fun linkParents(parent: Node) {
         this.parent = parent
         identifier?.linkParents(this)
     }
 
-    override fun accept(visitor: IAstModifyingVisitor) = visitor.visit(this)
+    override fun replaceChildNode(node: Node, replacement: Node) = throw FatalAstException("can't replace here")
     override fun accept(visitor: IAstVisitor) = visitor.visit(this)
+    override fun accept(visitor: AstWalker, parent: Node) = visitor.visit(this, parent)
 
     override fun toString(): String {
         return "Jump(addr: $address, identifier: $identifier, label: $generatedLabel;  pos=$position)"
@@ -489,20 +527,29 @@ class Jump(val address: Int?,
 }
 
 class FunctionCallStatement(override var target: IdentifierReference,
-                            override var arglist: MutableList<Expression>,
+                            override var args: MutableList<Expression>,
+                            val void: Boolean,
                             override val position: Position) : Statement(), IFunctionCall {
     override lateinit var parent: Node
-    override val expensiveToInline
-            get() = arglist.any { it !is NumericLiteralValue }
 
     override fun linkParents(parent: Node) {
         this.parent = parent
         target.linkParents(this)
-        arglist.forEach { it.linkParents(this) }
+        args.forEach { it.linkParents(this) }
+    }
+
+    override fun replaceChildNode(node: Node, replacement: Node) {
+        if(node===target)
+            target = replacement as IdentifierReference
+        else {
+            val idx = args.indexOfFirst { it===node }
+            args[idx] = replacement as Expression
+        }
+        replacement.parent = this
     }
 
-    override fun accept(visitor: IAstModifyingVisitor) = visitor.visit(this)
     override fun accept(visitor: IAstVisitor) = visitor.visit(this)
+    override fun accept(visitor: AstWalker, parent: Node) = visitor.visit(this, parent)
 
     override fun toString(): String {
         return "FunctionCallStatement(target=$target, pos=$position)"
@@ -511,22 +558,20 @@ class FunctionCallStatement(override var target: IdentifierReference,
 
 class InlineAssembly(val assembly: String, override val position: Position) : Statement() {
     override lateinit var parent: Node
-    override val expensiveToInline = true
 
     override fun linkParents(parent: Node) {
         this.parent = parent
     }
 
-    override fun accept(visitor: IAstModifyingVisitor) = visitor.visit(this)
+    override fun replaceChildNode(node: Node, replacement: Node) = throw FatalAstException("can't replace here")
     override fun accept(visitor: IAstVisitor) = visitor.visit(this)
+    override fun accept(visitor: AstWalker, parent: Node) = visitor.visit(this, parent)
 }
 
 class AnonymousScope(override var statements: MutableList<Statement>,
                      override val position: Position) : INameScope, Statement() {
     override val name: String
     override lateinit var parent: Node
-    override val expensiveToInline
-        get() = statements.any { it.expensiveToInline }
 
     companion object {
         private var sequenceNumber = 1
@@ -542,28 +587,27 @@ class AnonymousScope(override var statements: MutableList<Statement>,
         statements.forEach { it.linkParents(this) }
     }
 
-    override fun accept(visitor: IAstModifyingVisitor) = visitor.visit(this)
+    override fun replaceChildNode(node: Node, replacement: Node) {
+        require(replacement is Statement)
+        val idx = statements.indexOfFirst { it===node }
+        statements[idx] = replacement
+        replacement.parent = this
+    }
+
     override fun accept(visitor: IAstVisitor) = visitor.visit(this)
+    override fun accept(visitor: AstWalker, parent: Node) = visitor.visit(this, parent)
 }
 
 class NopStatement(override val position: Position): Statement() {
     override lateinit var parent: Node
-    override val expensiveToInline = false
 
     override fun linkParents(parent: Node) {
         this.parent = parent
     }
 
-    override fun accept(visitor: IAstModifyingVisitor) = visitor.visit(this)
+    override fun replaceChildNode(node: Node, replacement: Node) = throw FatalAstException("can't replace here")
     override fun accept(visitor: IAstVisitor) = visitor.visit(this)
-
-    companion object {
-        fun insteadOf(stmt: Statement): NopStatement {
-            val nop = NopStatement(stmt.position)
-            nop.parent = stmt.parent
-            return nop
-        }
-    }
+    override fun accept(visitor: AstWalker, parent: Node) = visitor.visit(this, parent)
 }
 
 // the subroutine class covers both the normal user-defined subroutines,
@@ -574,20 +618,14 @@ class Subroutine(override val name: String,
                  val returntypes: List<DataType>,
                  val asmParameterRegisters: List<RegisterOrStatusflag>,
                  val asmReturnvaluesRegisters: List<RegisterOrStatusflag>,
-                 val asmClobbers: Set<Register>,
+                 val asmClobbers: Set<CpuRegister>,
                  val asmAddress: Int?,
                  val isAsmSubroutine: Boolean,
                  override var statements: MutableList<Statement>,
                  override val position: Position) : Statement(), INameScope {
 
     var keepAlways: Boolean = false
-    override val expensiveToInline
-            get() = statements.any { it.expensiveToInline }
-
     override lateinit var parent: Node
-    val calledBy = mutableListOf<Node>()
-    val calls = mutableSetOf<Subroutine>()
-
     val scopedname: String by lazy { makeScopedName(name) }
 
     override fun linkParents(parent: Node) {
@@ -596,54 +634,30 @@ class Subroutine(override val name: String,
         statements.forEach { it.linkParents(this) }
     }
 
-    override fun accept(visitor: IAstModifyingVisitor) = visitor.visit(this)
+    override fun replaceChildNode(node: Node, replacement: Node) {
+        require(replacement is Statement)
+        val idx = statements.indexOfFirst { it===node }
+        statements[idx] = replacement
+        replacement.parent = this
+    }
+
     override fun accept(visitor: IAstVisitor) = visitor.visit(this)
+    override fun accept(visitor: AstWalker, parent: Node) = visitor.visit(this, parent)
 
     override fun toString(): String {
         return "Subroutine(name=$name, parameters=$parameters, returntypes=$returntypes, ${statements.size} statements, address=$asmAddress)"
     }
 
+    fun regXasResult() = asmReturnvaluesRegisters.any { it.registerOrPair in setOf(RegisterOrPair.X, RegisterOrPair.AX, RegisterOrPair.XY) }
+
     fun amountOfRtsInAsm(): Int = statements
             .asSequence()
             .filter { it is InlineAssembly }
             .map { (it as InlineAssembly).assembly }
             .count { " rti" in it || "\trti" in it || " rts" in it || "\trts" in it || " jmp" in it || "\tjmp" in it }
-
-    val canBeAsmSubroutine =false // TODO disabled for now, see below about problem with converting to asm subroutine
-//            !isAsmSubroutine
-//                    && ((parameters.size == 1 && parameters[0].type in setOf(DataType.BYTE, DataType.UBYTE, DataType.WORD, DataType.UWORD))
-//                    || (parameters.size == 2 && parameters.map { it.type }.all { it == DataType.BYTE || it == DataType.UBYTE }))
-
-    fun intoAsmSubroutine(): Subroutine {
-        // TODO turn subroutine into asm calling convention.   Requires rethinking of how parameters are handled (conflicts with local vardefs now, see AstIdentifierChecker...)
-        return this // TODO
-
-//        println("TO ASM   $this")  // TODO
-//        val paramregs = if (parameters.size == 1 && parameters[0].type in setOf(DataType.BYTE, DataType.UBYTE))
-//            listOf(RegisterOrStatusflag(RegisterOrPair.Y, null, null))
-//        else if (parameters.size == 1 && parameters[0].type in setOf(DataType.WORD, DataType.UWORD))
-//            listOf(RegisterOrStatusflag(RegisterOrPair.AY, null, null))
-//        else if (parameters.size == 2 && parameters.map { it.type }.all { it == DataType.BYTE || it == DataType.UBYTE })
-//            listOf(RegisterOrStatusflag(RegisterOrPair.A, null, null), RegisterOrStatusflag(RegisterOrPair.Y, null, null))
-//        else throw FatalAstException("cannot convert subroutine to asm parameters")
-//
-//        val asmsub=Subroutine(
-//                name,
-//                parameters,
-//                returntypes,
-//                paramregs,
-//                emptyList(),
-//                emptySet(),
-//                null,
-//                true,
-//                statements,
-//                position
-//        )
-//        asmsub.linkParents(parent)
-//        return asmsub
-    }
 }
 
+
 open class SubroutineParameter(val name: String,
                                val type: DataType,
                                override val position: Position) : Node {
@@ -652,6 +666,10 @@ open class SubroutineParameter(val name: String,
     override fun linkParents(parent: Node) {
         this.parent = parent
     }
+
+    override fun replaceChildNode(node: Node, replacement: Node) {
+        throw FatalAstException("can't replace anything in a subroutineparameter node")
+    }
 }
 
 class IfStatement(var condition: Expression,
@@ -659,8 +677,6 @@ class IfStatement(var condition: Expression,
                   var elsepart: AnonymousScope,
                   override val position: Position) : Statement() {
     override lateinit var parent: Node
-    override val expensiveToInline: Boolean
-        get() = truepart.expensiveToInline || elsepart.expensiveToInline
 
     override fun linkParents(parent: Node) {
         this.parent = parent
@@ -669,8 +685,19 @@ class IfStatement(var condition: Expression,
         elsepart.linkParents(this)
     }
 
-    override fun accept(visitor: IAstModifyingVisitor) = visitor.visit(this)
+    override fun replaceChildNode(node: Node, replacement: Node) {
+        when {
+            node===condition -> condition = replacement as Expression
+            node===truepart -> truepart = replacement as AnonymousScope
+            node===elsepart -> elsepart = replacement as AnonymousScope
+            else -> throw FatalAstException("invalid replace")
+        }
+        replacement.parent = this
+    }
+
     override fun accept(visitor: IAstVisitor) = visitor.visit(this)
+    override fun accept(visitor: AstWalker, parent: Node) = visitor.visit(this, parent)
+
 }
 
 class BranchStatement(var condition: BranchCondition,
@@ -678,8 +705,6 @@ class BranchStatement(var condition: BranchCondition,
                       var elsepart: AnonymousScope,
                       override val position: Position) : Statement() {
     override lateinit var parent: Node
-    override val expensiveToInline: Boolean
-        get() = truepart.expensiveToInline || elsepart.expensiveToInline
 
     override fun linkParents(parent: Node) {
         this.parent = parent
@@ -687,40 +712,57 @@ class BranchStatement(var condition: BranchCondition,
         elsepart.linkParents(this)
     }
 
-    override fun accept(visitor: IAstModifyingVisitor) = visitor.visit(this)
+    override fun replaceChildNode(node: Node, replacement: Node) {
+        when {
+            node===truepart -> truepart = replacement as AnonymousScope
+            node===elsepart -> elsepart = replacement as AnonymousScope
+            else -> throw FatalAstException("invalid replace")
+        }
+        replacement.parent = this
+    }
+
     override fun accept(visitor: IAstVisitor) = visitor.visit(this)
+    override fun accept(visitor: AstWalker, parent: Node) = visitor.visit(this, parent)
+
 }
 
-class ForLoop(val loopRegister: Register?,
-              val decltype: DataType?,
-              val zeropage: ZeropageWish,
-              var loopVar: IdentifierReference?,
+class ForLoop(var loopVar: IdentifierReference,
               var iterable: Expression,
               var body: AnonymousScope,
               override val position: Position) : Statement() {
     override lateinit var parent: Node
-    override val expensiveToInline = true
 
     override fun linkParents(parent: Node) {
         this.parent=parent
-        loopVar?.linkParents(if(decltype==null) this else body)
+        loopVar.linkParents(this)
         iterable.linkParents(this)
         body.linkParents(this)
     }
 
-    override fun accept(visitor: IAstModifyingVisitor) = visitor.visit(this)
+    override fun replaceChildNode(node: Node, replacement: Node) {
+        when {
+            node===loopVar -> loopVar = replacement as IdentifierReference
+            node===iterable -> iterable = replacement as Expression
+            node===body -> body = replacement as AnonymousScope
+            else -> throw FatalAstException("invalid replace")
+        }
+        replacement.parent = this
+    }
+
     override fun accept(visitor: IAstVisitor) = visitor.visit(this)
+    override fun accept(visitor: AstWalker, parent: Node) = visitor.visit(this, parent)
 
     override fun toString(): String {
-        return "ForLoop(loopVar: $loopVar, loopReg: $loopRegister, iterable: $iterable, pos=$position)"
+        return "ForLoop(loopVar: $loopVar, iterable: $iterable, pos=$position)"
     }
+
+    fun loopVarDt(program: Program) = loopVar.inferType(program)
 }
 
 class WhileLoop(var condition: Expression,
                 var body: AnonymousScope,
                 override val position: Position) : Statement() {
     override lateinit var parent: Node
-    override val expensiveToInline = true
 
     override fun linkParents(parent: Node) {
         this.parent = parent
@@ -728,15 +770,45 @@ class WhileLoop(var condition: Expression,
         body.linkParents(this)
     }
 
-    override fun accept(visitor: IAstModifyingVisitor) = visitor.visit(this)
+    override fun replaceChildNode(node: Node, replacement: Node) {
+        when {
+            node===condition -> condition = replacement as Expression
+            node===body -> body = replacement as AnonymousScope
+            else -> throw FatalAstException("invalid replace")
+        }
+        replacement.parent = this
+    }
+
     override fun accept(visitor: IAstVisitor) = visitor.visit(this)
+    override fun accept(visitor: AstWalker, parent: Node) = visitor.visit(this, parent)
 }
 
-class RepeatLoop(var body: AnonymousScope,
-                 var untilCondition: Expression,
-                 override val position: Position) : Statement() {
+class RepeatLoop(var iterations: Expression?, var body: AnonymousScope, override val position: Position) : Statement() {
+    override lateinit var parent: Node
+
+    override fun linkParents(parent: Node) {
+        this.parent = parent
+        iterations?.linkParents(this)
+        body.linkParents(this)
+    }
+
+    override fun replaceChildNode(node: Node, replacement: Node) {
+        when {
+            node===iterations -> iterations = replacement as Expression
+            node===body -> body = replacement as AnonymousScope
+            else -> throw FatalAstException("invalid replace")
+        }
+        replacement.parent = this
+    }
+
+    override fun accept(visitor: IAstVisitor) = visitor.visit(this)
+    override fun accept(visitor: AstWalker, parent: Node) = visitor.visit(this, parent)
+}
+
+class UntilLoop(var body: AnonymousScope,
+                var untilCondition: Expression,
+                override val position: Position) : Statement() {
     override lateinit var parent: Node
-    override val expensiveToInline = true
 
     override fun linkParents(parent: Node) {
         this.parent = parent
@@ -744,15 +816,23 @@ class RepeatLoop(var body: AnonymousScope,
         body.linkParents(this)
     }
 
-    override fun accept(visitor: IAstModifyingVisitor) = visitor.visit(this)
+    override fun replaceChildNode(node: Node, replacement: Node) {
+        when {
+            node===untilCondition -> untilCondition = replacement as Expression
+            node===body -> body = replacement as AnonymousScope
+            else -> throw FatalAstException("invalid replace")
+        }
+        replacement.parent = this
+    }
+
     override fun accept(visitor: IAstVisitor) = visitor.visit(this)
+    override fun accept(visitor: AstWalker, parent: Node) = visitor.visit(this, parent)
 }
 
 class WhenStatement(var condition: Expression,
                     var choices: MutableList<WhenChoice>,
                     override val position: Position): Statement() {
     override lateinit var parent: Node
-    override val expensiveToInline: Boolean = true
 
     override fun linkParents(parent: Node) {
         this.parent = parent
@@ -760,6 +840,16 @@ class WhenStatement(var condition: Expression,
         choices.forEach { it.linkParents(this) }
     }
 
+    override fun replaceChildNode(node: Node, replacement: Node) {
+        if(node===condition)
+            condition = replacement as Expression
+        else {
+            val idx = choices.withIndex().find { it.value===node }!!.index
+            choices[idx] = replacement as WhenChoice
+        }
+        replacement.parent = this
+    }
+
     fun choiceValues(program: Program): List<Pair<List<Int>?, WhenChoice>> {
         // only gives sensible results when the choices are all valid (constant integers)
         val result = mutableListOf<Pair<List<Int>?, WhenChoice>>()
@@ -778,7 +868,7 @@ class WhenStatement(var condition: Expression,
     }
 
     override fun accept(visitor: IAstVisitor) = visitor.visit(this)
-    override fun accept(visitor: IAstModifyingVisitor) = visitor.visit(this)
+    override fun accept(visitor: AstWalker, parent: Node) = visitor.visit(this, parent)
 }
 
 class WhenChoice(var values: List<Expression>?,           // if null,  this is the 'else' part
@@ -792,12 +882,18 @@ class WhenChoice(var values: List<Expression>?,           // if null,  this is t
         this.parent = parent
     }
 
+    override fun replaceChildNode(node: Node, replacement: Node) {
+        require(replacement is AnonymousScope && node===statements)
+        statements = replacement
+        replacement.parent = this
+    }
+
     override fun toString(): String {
         return "Choice($values at $position)"
     }
 
     fun accept(visitor: IAstVisitor) = visitor.visit(this)
-    fun accept(visitor: IAstModifyingVisitor) = visitor.visit(this)
+    fun accept(visitor: AstWalker, parent: Node) = visitor.visit(this, parent)
 }
 
 
@@ -806,18 +902,24 @@ class StructDecl(override val name: String,
                  override val position: Position): Statement(), INameScope {
 
     override lateinit var parent: Node
-    override val expensiveToInline: Boolean = true
 
     override fun linkParents(parent: Node) {
         this.parent = parent
         this.statements.forEach { it.linkParents(this) }
     }
 
+    override fun replaceChildNode(node: Node, replacement: Node) {
+        require(replacement is Statement)
+        val idx = statements.indexOfFirst { it===node }
+        statements[idx] = replacement
+        replacement.parent = this
+    }
+
     val numberOfElements: Int
         get() = this.statements.size
 
     override fun accept(visitor: IAstVisitor) = visitor.visit(this)
-    override fun accept(visitor: IAstModifyingVisitor) = visitor.visit(this)
+    override fun accept(visitor: AstWalker, parent: Node) = visitor.visit(this, parent)
 
     fun nameOfFirstMember() = (statements.first() as VarDecl).name
 }
@@ -830,11 +932,16 @@ class DirectMemoryWrite(var addressExpression: Expression, override val position
         this.addressExpression.linkParents(this)
     }
 
+    override fun replaceChildNode(node: Node, replacement: Node) {
+        require(replacement is Expression && node===addressExpression)
+        addressExpression = replacement
+        replacement.parent = this
+    }
+
     override fun toString(): String {
         return "DirectMemoryWrite($addressExpression)"
     }
 
     fun accept(visitor: IAstVisitor) = visitor.visit(this)
-    fun accept(visitor: IAstModifyingVisitor) = visitor.visit(this)
+    fun accept(visitor: AstWalker, parent: Node) = visitor.visit(this, parent)
 }
-

compiler/src/prog8/compiler/AssemblyError.kt

@@ -0,0 +1,3 @@
+package prog8.compiler
+
+internal class AssemblyError(msg: String) : RuntimeException(msg)

compiler/src/prog8/compiler/BeforeAsmGenerationAstChanger.kt

@@ -0,0 +1,106 @@
+package prog8.compiler
+
+import prog8.ast.Node
+import prog8.ast.Program
+import prog8.ast.base.*
+import prog8.ast.expressions.*
+import prog8.ast.processing.AstWalker
+import prog8.ast.processing.IAstModification
+import prog8.ast.statements.*
+
+
+internal class BeforeAsmGenerationAstChanger(val program: Program, val errors: ErrorReporter) : AstWalker() {
+
+    private val noModifications = emptyList<IAstModification>()
+
+    override fun after(decl: VarDecl, parent: Node): Iterable<IAstModification> {
+        if (decl.value == null && decl.type == VarDeclType.VAR && decl.datatype in NumericDatatypes) {
+            // a numeric vardecl without an initial value is initialized with zero.
+            decl.value = decl.zeroElementValue()
+        }
+        return noModifications
+    }
+
+    override fun after(scope: AnonymousScope, parent: Node): Iterable<IAstModification> {
+        val decls = scope.statements.filterIsInstance<VarDecl>()
+        val sub = scope.definingSubroutine()
+        if (sub != null) {
+            val existingVariables = sub.statements.filterIsInstance<VarDecl>().associateBy { it.name }
+            var conflicts = false
+            decls.forEach {
+                val existing = existingVariables[it.name]
+                if (existing != null) {
+                    errors.err("variable ${it.name} already defined in subroutine ${sub.name} at ${existing.position}", it.position)
+                    conflicts = true
+                }
+            }
+            if (!conflicts) {
+                val numericVarsWithValue = decls.filter { it.value != null && it.datatype in NumericDatatypes }
+                return numericVarsWithValue.map {
+                    val initValue = it.value!!  // assume here that value has always been set by now
+                    it.value = null     // make sure no value init assignment for this vardecl will be created later (would be superfluous)
+                    val target = AssignTarget(IdentifierReference(listOf(it.name), it.position), null, null, it.position)
+                    val assign = Assignment(target, initValue, it.position)
+                    initValue.parent = assign
+                    IAstModification.InsertFirst(assign, scope)
+                } +  decls.map { IAstModification.ReplaceNode(it, NopStatement(it.position), scope) } +
+                     decls.map { IAstModification.InsertFirst(it, sub) }    // move it up to the subroutine
+            }
+        }
+        return noModifications
+    }
+
+    override fun after(subroutine: Subroutine, parent: Node): Iterable<IAstModification> {
+        // add the implicit return statement at the end (if it's not there yet), but only if it's not a kernel routine.
+        // and if an assembly block doesn't contain a rts/rti, and some other situations.
+        val mods = mutableListOf<IAstModification>()
+        val returnStmt = Return(null, subroutine.position)
+        if (subroutine.asmAddress == null
+                && subroutine.statements.isNotEmpty()
+                && subroutine.amountOfRtsInAsm() == 0
+                && subroutine.statements.lastOrNull { it !is VarDecl } !is Return
+                && subroutine.statements.last() !is Subroutine) {
+            mods += IAstModification.InsertLast(returnStmt, subroutine)
+        }
+
+        // precede a subroutine with a return to avoid falling through into the subroutine from code above it
+        val outerScope = subroutine.definingScope()
+        val outerStatements = outerScope.statements
+        val subroutineStmtIdx = outerStatements.indexOf(subroutine)
+        if (subroutineStmtIdx > 0
+                && outerStatements[subroutineStmtIdx - 1] !is Jump
+                && outerStatements[subroutineStmtIdx - 1] !is Subroutine
+                && outerStatements[subroutineStmtIdx - 1] !is Return
+                && outerScope !is Block) {
+            mods += IAstModification.InsertAfter(outerStatements[subroutineStmtIdx - 1], returnStmt, outerScope as Node)
+        }
+
+        return mods
+    }
+
+    override fun after(typecast: TypecastExpression, parent: Node): Iterable<IAstModification> {
+        // see if we can remove superfluous typecasts (outside of expressions)
+        // such as casting byte<->ubyte,  word<->uword
+        // Also the special typecast of a reference type (str, array) to an UWORD will be changed into address-of.
+        val sourceDt = typecast.expression.inferType(program).typeOrElse(DataType.STRUCT)
+        if (typecast.type in ByteDatatypes && sourceDt in ByteDatatypes
+                || typecast.type in WordDatatypes && sourceDt in WordDatatypes) {
+            if(typecast.parent !is Expression) {
+                return listOf(IAstModification.ReplaceNode(typecast, typecast.expression, parent))
+            }
+        }
+        else if(sourceDt in PassByReferenceDatatypes) {
+            if(typecast.type==DataType.UWORD) {
+                return listOf(IAstModification.ReplaceNode(
+                        typecast,
+                        AddressOf(typecast.expression as IdentifierReference, typecast.position),
+                        parent
+                ))
+            } else {
+                errors.err("cannot cast pass-by-reference value to type ${typecast.type} (only to UWORD)", typecast.position)
+            }
+        }
+
+        return noModifications
+    }
+}

compiler/src/prog8/compiler/Compiler.kt

@@ -1,13 +1,8 @@
 package prog8.compiler
 
-import prog8.ast.base.ArrayDatatypes
-import prog8.ast.base.DataType
-import prog8.ast.base.StringDatatypes
-import prog8.ast.expressions.AddressOf
 import java.io.File
 import java.io.InputStream
 import java.nio.file.Path
-import java.util.*
 import kotlin.math.abs
 
 enum class OutputType {
@@ -28,8 +23,6 @@ enum class ZeropageType {
     DONTUSE
 }
 
-data class IntegerOrAddressOf(val integer: Int?, val addressOf: AddressOf?)
-
 data class CompilationOptions(val output: OutputType,
                               val launcher: LauncherType,
                               val zeropage: ZeropageType,
@@ -73,83 +66,3 @@ fun loadAsmIncludeFile(filename: String, source: Path): String {
 internal fun tryGetEmbeddedResource(name: String): InputStream? {
     return object{}.javaClass.getResourceAsStream("/prog8lib/$name")
 }
-
-class HeapValues {
-    data class HeapValue(val type: DataType, val str: String?, val array: Array<IntegerOrAddressOf>?, val doubleArray: DoubleArray?) {
-        override fun equals(other: Any?): Boolean {
-            if (this === other) return true
-            if (javaClass != other?.javaClass) return false
-            other as HeapValue
-            return type==other.type && str==other.str && Arrays.equals(array, other.array) && Arrays.equals(doubleArray, other.doubleArray)
-        }
-
-        override fun hashCode(): Int {
-            var result = type.hashCode()
-            result = 31 * result + (str?.hashCode() ?: 0)
-            result = 31 * result + (array?.let { Arrays.hashCode(it) } ?: 0)
-            result = 31 * result + (doubleArray?.let { Arrays.hashCode(it) } ?: 0)
-            return result
-        }
-
-        val arraysize: Int = array?.size ?: doubleArray?.size ?: 0
-    }
-
-    private val heap = mutableMapOf<Int, HeapValue>()
-    private var heapId = 1
-
-    fun size(): Int = heap.size
-
-    fun addString(type: DataType, str: String): Int {
-        if (str.length > 255)
-            throw IllegalArgumentException("string length must be 0-255")
-
-        // strings are 'interned' and shared if they're the isSameAs
-        val value = HeapValue(type, str, null, null)
-
-        val existing = heap.filter { it.value==value }.map { it.key }.firstOrNull()
-        if(existing!=null)
-            return existing
-        val newId = heapId++
-        heap[newId] = value
-        return newId
-    }
-
-    fun addIntegerArray(type: DataType, array: Array<IntegerOrAddressOf>): Int {
-        // arrays are never shared, don't check for existing
-        if(type !in ArrayDatatypes)
-            throw CompilerException("wrong array type")
-        val newId = heapId++
-        heap[newId] = HeapValue(type, null, array, null)
-        return newId
-    }
-
-    fun addDoublesArray(darray: DoubleArray): Int {
-        // arrays are never shared, don't check for existing
-        val newId = heapId++
-        heap[newId] = HeapValue(DataType.ARRAY_F, null, null, darray)
-        return newId
-    }
-
-    fun update(heapId: Int, str: String) {
-        val oldVal = heap[heapId] ?: throw IllegalArgumentException("heapId not found in heap")
-        if(oldVal.type in StringDatatypes) {
-            if (oldVal.str!!.length != str.length)
-                throw IllegalArgumentException("heap string length mismatch")
-            heap[heapId] = oldVal.copy(str = str)
-        }
-        else throw IllegalArgumentException("heap data type mismatch")
-    }
-
-    fun update(heapId: Int, heapval: HeapValue) {
-        if(heapId !in heap)
-            throw IllegalArgumentException("heapId not found in heap")
-        heap[heapId] = heapval
-    }
-
-    fun get(heapId: Int): HeapValue {
-        return heap[heapId] ?:
-        throw IllegalArgumentException("heapId $heapId not found in heap")
-    }
-
-    fun allEntries() = heap.entries
-}

compiler/src/prog8/compiler/Main.kt

@@ -4,14 +4,13 @@ import prog8.ast.AstToSourceCode
 import prog8.ast.Program
 import prog8.ast.base.*
 import prog8.ast.statements.Directive
-import prog8.compiler.target.c64.MachineDefinition
-import prog8.compiler.target.c64.codegen2.AsmGen2
+import prog8.compiler.target.CompilationTarget
+import prog8.optimizer.UnusedCodeRemover
 import prog8.optimizer.constantFold
 import prog8.optimizer.optimizeStatements
 import prog8.optimizer.simplifyExpressions
+import prog8.parser.ModuleImporter
 import prog8.parser.ParsingFailedError
-import prog8.parser.importLibraryModule
-import prog8.parser.importModule
 import prog8.parser.moduleName
 import java.nio.file.Path
 import kotlin.system.measureTimeMillis
@@ -24,89 +23,34 @@ class CompilationResult(val success: Boolean,
 
 
 fun compileProgram(filepath: Path,
-                   optimize: Boolean, optimizeInlining: Boolean,
-                   writeAssembly: Boolean): CompilationResult {
+                   optimize: Boolean,
+                   writeAssembly: Boolean,
+                   outputDir: Path): CompilationResult {
+    var programName = ""
     lateinit var programAst: Program
-    var programName: String? = null
-
-    var importedFiles: List<Path> = emptyList()
-    var success=false
+    lateinit var importedFiles: List<Path>
+    val errors = ErrorReporter()
 
     try {
         val totalTime = measureTimeMillis {
             // import main module and everything it needs
-            println("Parsing...")
-            programAst = Program(moduleName(filepath.fileName), mutableListOf())
-            importModule(programAst, filepath)
+            val (ast, compilationOptions, imported) = parseImports(filepath, errors)
+            programAst = ast
+            importedFiles = imported
+            processAst(programAst, errors, compilationOptions)
+            if (optimize)
+                optimizeAst(programAst, errors)
+            postprocessAst(programAst, errors, compilationOptions)
 
-            importedFiles = programAst.modules.filter { !it.source.startsWith("@embedded@") }.map{ it.source }
+            // printAst(programAst)
 
-            val compilerOptions = determineCompilationOptions(programAst)
-            if (compilerOptions.launcher == LauncherType.BASIC && compilerOptions.output != OutputType.PRG)
-                throw ParsingFailedError("${programAst.modules.first().position} BASIC launcher requires output type PRG.")
-
-            // if we're producing a PRG or BASIC program, include the c64utils and c64lib libraries
-            if (compilerOptions.launcher == LauncherType.BASIC || compilerOptions.output == OutputType.PRG) {
-                importLibraryModule(programAst, "c64lib")
-                importLibraryModule(programAst, "c64utils")
-            }
-
-            // always import prog8lib and math
-            importLibraryModule(programAst, "math")
-            importLibraryModule(programAst, "prog8lib")
-
-
-            // perform initial syntax checks and constant folding
-            println("Syntax check...")
-            val time1 = measureTimeMillis {
-                programAst.checkIdentifiers()
-            }
-
-            //println(" time1: $time1")
-            val time2 = measureTimeMillis {
-                programAst.constantFold()
-            }
-            //println(" time2: $time2")
-            val time3 = measureTimeMillis {
-                programAst.removeNopsFlattenAnonScopes()
-                programAst.reorderStatements()     // reorder statements and add type casts, to please the compiler later
-            }
-            //println(" time3: $time3")
-            val time4 = measureTimeMillis {
-                programAst.checkValid(compilerOptions)          // check if tree is valid
-            }
-            //println(" time4: $time4")
-
-            programAst.checkIdentifiers()
-            if (optimize) {
-                // optimize the parse tree
-                println("Optimizing...")
-                while (true) {
-                    // keep optimizing expressions and statements until no more steps remain
-                    val optsDone1 = programAst.simplifyExpressions()
-                    val optsDone2 = programAst.optimizeStatements(optimizeInlining)
-                    if (optsDone1 + optsDone2 == 0)
-                        break
-                }
-            }
-
-            programAst.removeNopsFlattenAnonScopes()
-            programAst.checkValid(compilerOptions)          // check if final tree is valid
-            programAst.checkRecursion()         // check if there are recursive subroutine calls
-
-            printAst(programAst)
-
-            if(writeAssembly) {
-                // asm generation directly from the Ast, no need for intermediate code
-                val zeropage = MachineDefinition.C64Zeropage(compilerOptions)
-                programAst.anonscopeVarsCleanup()
-                val assembly = AsmGen2(programAst, compilerOptions, zeropage).compileToAssembly(optimize)
-                assembly.assemble(compilerOptions)
-                programName = assembly.name
-            }
-            success = true
+            if(writeAssembly)
+                programName = writeAssembly(programAst, errors, outputDir, optimize, compilationOptions)
         }
+        System.out.flush()
+        System.err.flush()
         println("\nTotal compilation+assemble time: ${totalTime / 1000.0} sec.")
+        return CompilationResult(true, programAst, programName, importedFiles)
 
     } catch (px: ParsingFailedError) {
         System.err.print("\u001b[91m")  // bright red
@@ -129,16 +73,35 @@ fun compileProgram(filepath: Path,
         System.out.flush()
         throw x
     }
-    return CompilationResult(success, programAst, programName ?: "", importedFiles)
+
+    return CompilationResult(false, Program("failed", mutableListOf()), programName, emptyList())
 }
 
-fun printAst(programAst: Program) {
-    println()
-    val printer = AstToSourceCode(::print, programAst)
-    printer.visit(programAst)
-    println()
-}
+private fun parseImports(filepath: Path, errors: ErrorReporter): Triple<Program, CompilationOptions, List<Path>> {
+    println("Parsing...")
+    val importer = ModuleImporter()
+    val programAst = Program(moduleName(filepath.fileName), mutableListOf())
+    importer.importModule(programAst, filepath)
+    errors.handle()
 
+    val importedFiles = programAst.modules.filter { !it.source.startsWith("@embedded@") }.map { it.source }
+
+    val compilerOptions = determineCompilationOptions(programAst)
+    if (compilerOptions.launcher == LauncherType.BASIC && compilerOptions.output != OutputType.PRG)
+        throw ParsingFailedError("${programAst.modules.first().position} BASIC launcher requires output type PRG.")
+
+    // if we're producing a PRG or BASIC program, include the c64utils and c64lib libraries
+    if (compilerOptions.launcher == LauncherType.BASIC || compilerOptions.output == OutputType.PRG) {
+        importer.importLibraryModule(programAst, "c64lib")
+        importer.importLibraryModule(programAst, "c64utils")
+    }
+
+    // always import prog8lib and math
+    importer.importLibraryModule(programAst, "math")
+    importer.importLibraryModule(programAst, "prog8lib")
+    errors.handle()
+    return Triple(programAst, compilerOptions, importedFiles)
+}
 
 private fun determineCompilationOptions(program: Program): CompilationOptions {
     val mainModule = program.modules.first()
@@ -175,3 +138,77 @@ private fun determineCompilationOptions(program: Program): CompilationOptions {
             zpType, zpReserved, floatsEnabled
     )
 }
+
+private fun processAst(programAst: Program, errors: ErrorReporter, compilerOptions: CompilationOptions) {
+    // perform initial syntax checks and processings
+    println("Processing...")
+    programAst.checkIdentifiers(errors)
+    errors.handle()
+    programAst.constantFold(errors)
+    errors.handle()
+    programAst.reorderStatements()
+    programAst.addTypecasts(errors)
+    errors.handle()
+    programAst.variousCleanups()
+    programAst.checkValid(compilerOptions, errors)
+    errors.handle()
+    programAst.checkIdentifiers(errors)
+    errors.handle()
+}
+
+private fun optimizeAst(programAst: Program, errors: ErrorReporter) {
+    // optimize the parse tree
+    println("Optimizing...")
+    while (true) {
+        // keep optimizing expressions and statements until no more steps remain
+        val optsDone1 = programAst.simplifyExpressions()
+        val optsDone2 = programAst.optimizeStatements(errors)
+        programAst.constantFold(errors) // because simplified statements and expressions could give rise to more constants that can be folded away:
+        errors.handle()
+        if (optsDone1 + optsDone2 == 0)
+            break
+    }
+
+    val remover = UnusedCodeRemover()
+    remover.visit(programAst)
+    remover.applyModifications()
+}
+
+private fun postprocessAst(programAst: Program, errors: ErrorReporter, compilerOptions: CompilationOptions) {
+    programAst.addTypecasts(errors)
+    errors.handle()
+    programAst.variousCleanups()
+    programAst.checkValid(compilerOptions, errors)          // check if final tree is still valid
+    errors.handle()
+    programAst.checkRecursion(errors)         // check if there are recursive subroutine calls
+    errors.handle()
+    programAst.verifyFunctionArgTypes()
+}
+
+private fun writeAssembly(programAst: Program, errors: ErrorReporter, outputDir: Path,
+                          optimize: Boolean, compilerOptions: CompilationOptions): String {
+    // asm generation directly from the Ast,
+    val zeropage = CompilationTarget.machine.getZeropage(compilerOptions)
+    programAst.processAstBeforeAsmGeneration(errors)
+    errors.handle()
+
+    // printAst(programAst)
+
+    val assembly = CompilationTarget.asmGenerator(
+            programAst,
+            errors,
+            zeropage,
+            compilerOptions,
+            outputDir).compileToAssembly(optimize)
+    assembly.assemble(compilerOptions)
+    errors.handle()
+    return assembly.name
+}
+
+fun printAst(programAst: Program) {
+    println()
+    val printer = AstToSourceCode(::print, programAst)
+    printer.visit(programAst)
+    println()
+}
+

compiler/src/prog8/compiler/Zeropage.kt

@@ -13,10 +13,10 @@ abstract class Zeropage(protected val options: CompilationOptions) {
 
     val allowedDatatypes = NumericDatatypes
 
-    fun available() = free.size
+    fun available() = if(options.zeropage==ZeropageType.DONTUSE) 0 else free.size
 
-    fun allocate(scopedname: String, datatype: DataType, position: Position?): Int {
-        assert(scopedname.isEmpty() || !allocations.values.any { it.first==scopedname } ) {"isSameAs scopedname can't be allocated twice"}
+    fun allocate(scopedname: String, datatype: DataType, position: Position?, errors: ErrorReporter): Int {
+        assert(scopedname.isEmpty() || !allocations.values.any { it.first==scopedname } ) {"scopedname can't be allocated twice"}
 
         if(options.zeropage==ZeropageType.DONTUSE)
             throw CompilerException("zero page usage has been disabled")
@@ -28,9 +28,9 @@ abstract class Zeropage(protected val options: CompilationOptions) {
                     DataType.FLOAT -> {
                         if (options.floats) {
                             if(position!=null)
-                                printWarning("allocated a large value (float) in zeropage", position)
+                                errors.warn("allocated a large value (float) in zeropage", position)
                             else
-                                printWarning("$scopedname: allocated a large value (float) in zeropage")
+                                errors.warn("$scopedname: allocated a large value (float) in zeropage", position ?: Position.DUMMY)
                             5
                         } else throw CompilerException("floating point option not enabled")
                     }
@@ -39,13 +39,13 @@ abstract class Zeropage(protected val options: CompilationOptions) {
 
         if(free.size > 0) {
             if(size==1) {
-                for(candidate in free.min()!! .. free.max()!!+1) {
+                for(candidate in free.minOrNull()!! .. free.maxOrNull()!!+1) {
                     if(loneByte(candidate))
                         return makeAllocation(candidate, 1, datatype, scopedname)
                 }
                 return makeAllocation(free[0], 1, datatype, scopedname)
             }
-            for(candidate in free.min()!! .. free.max()!!+1) {
+            for(candidate in free.minOrNull()!! .. free.maxOrNull()!!+1) {
                 if (sequentialFree(candidate, size))
                     return makeAllocation(candidate, size, datatype, scopedname)
             }

compiler/src/prog8/compiler/target/CompilationTarget.kt

@@ -0,0 +1,18 @@
+package prog8.compiler.target
+
+import prog8.ast.Program
+import prog8.ast.base.ErrorReporter
+import prog8.compiler.CompilationOptions
+import prog8.compiler.Zeropage
+import java.nio.file.Path
+
+
+internal interface CompilationTarget {
+    companion object {
+        lateinit var name: String
+        lateinit var machine: IMachineDefinition
+        lateinit var encodeString: (str: String, altEncoding: Boolean) -> List<Short>
+        lateinit var decodeString: (bytes: List<Short>, altEncoding: Boolean) -> String
+        lateinit var asmGenerator: (Program, ErrorReporter, Zeropage, CompilationOptions, Path) -> IAssemblyGenerator
+    }
+}

compiler/src/prog8/compiler/target/IAssemblyGenerator.kt

@@ -0,0 +1,14 @@
+package prog8.compiler.target
+
+import prog8.compiler.CompilationOptions
+
+internal interface IAssemblyGenerator {
+    fun compileToAssembly(optimize: Boolean): IAssemblyProgram
+}
+
+internal const val generatedLabelPrefix = "_prog8_label_"
+
+internal interface IAssemblyProgram {
+    val name: String
+    fun assemble(options: CompilationOptions)
+}

compiler/src/prog8/compiler/target/IMachineDefinition.kt

@@ -0,0 +1,15 @@
+package prog8.compiler.target
+
+import prog8.compiler.CompilationOptions
+import prog8.compiler.Zeropage
+
+
+interface IMachineDefinition {
+    val FLOAT_MAX_NEGATIVE: Double
+    val FLOAT_MAX_POSITIVE: Double
+    val FLOAT_MEM_SIZE: Int
+
+    val opcodeNames: Set<String>
+
+    fun getZeropage(compilerOptions: CompilationOptions): Zeropage
+}

compiler/src/prog8/compiler/target/c64/AssemblyProgram.kt

@@ -2,70 +2,72 @@ package prog8.compiler.target.c64
 
 import prog8.compiler.CompilationOptions
 import prog8.compiler.OutputType
-import java.io.File
+import prog8.compiler.target.IAssemblyProgram
+import prog8.compiler.target.generatedLabelPrefix
+import java.nio.file.Path
 import kotlin.system.exitProcess
 
-class AssemblyProgram(val name: String) {
-    private val assemblyFile = "$name.asm"
-    private val viceMonListFile = "$name.vice-mon-list"
+class AssemblyProgram(override val name: String, outputDir: Path) : IAssemblyProgram {
+    private val assemblyFile = outputDir.resolve("$name.asm")
+    private val prgFile = outputDir.resolve("$name.prg")
+    private val binFile = outputDir.resolve("$name.bin")
+    private val viceMonListFile = outputDir.resolve("$name.vice-mon-list")
 
-    companion object {
-        // 6502 opcodes (including aliases and illegal opcodes), these cannot be used as variable or label names
-        val opcodeNames = setOf("adc", "ahx", "alr", "anc", "and", "ane", "arr", "asl", "asr", "axs", "bcc", "bcs",
-                "beq", "bge", "bit", "blt", "bmi", "bne", "bpl", "brk", "bvc", "bvs", "clc",
-                "cld", "cli", "clv", "cmp", "cpx", "cpy", "dcm", "dcp", "dec", "dex", "dey",
-                "eor", "gcc", "gcs", "geq", "gge", "glt", "gmi", "gne", "gpl", "gvc", "gvs",
-                "inc", "ins", "inx", "iny", "isb", "isc", "jam", "jmp", "jsr", "lae", "las",
-                "lax", "lda", "lds", "ldx", "ldy", "lsr", "lxa", "nop", "ora", "pha", "php",
-                "pla", "plp", "rla", "rol", "ror", "rra", "rti", "rts", "sax", "sbc", "sbx",
-                "sec", "sed", "sei", "sha", "shl", "shr", "shs", "shx", "shy", "slo", "sre",
-                "sta", "stx", "sty", "tas", "tax", "tay", "tsx", "txa", "txs", "tya", "xaa")
-    }
-
-
-    fun assemble(options: CompilationOptions) {
+    override fun assemble(options: CompilationOptions) {
         // add "-Wlong-branch"  to see warnings about conversion of branch instructions to jumps
         val command = mutableListOf("64tass", "--ascii", "--case-sensitive", "--long-branch",
                 "-Wall", "-Wno-strict-bool", "-Wno-shadow", "-Werror", "-Wno-error=long-branch",
-                "--dump-labels", "--vice-labels", "-l", viceMonListFile, "--no-monitor")
+                "--dump-labels", "--vice-labels", "-l", viceMonListFile.toString(), "--no-monitor")
 
-        val outFile = when(options.output) {
+        val outFile = when (options.output) {
             OutputType.PRG -> {
                 command.add("--cbm-prg")
                 println("\nCreating C-64 prg.")
-                "$name.prg"
+                prgFile
             }
             OutputType.RAW -> {
                 command.add("--nostart")
                 println("\nCreating raw binary.")
-                "$name.bin"
+                binFile
             }
         }
-        command.addAll(listOf("--output", outFile, assemblyFile))
+        command.addAll(listOf("--output", outFile.toString(), assemblyFile.toString()))
 
         val proc = ProcessBuilder(command).inheritIO().start()
         val result = proc.waitFor()
-        if(result!=0) {
+        if (result != 0) {
             System.err.println("assembler failed with returncode $result")
             exitProcess(result)
         }
 
+        removeGeneratedLabelsFromMonlist()
         generateBreakpointList()
     }
 
+    private fun removeGeneratedLabelsFromMonlist() {
+        val pattern = Regex("""al (\w+) \S+${generatedLabelPrefix}.+?""")
+        val lines = viceMonListFile.toFile().readLines()
+        viceMonListFile.toFile().outputStream().bufferedWriter().use {
+            for (line in lines) {
+                if(pattern.matchEntire(line)==null)
+                    it.write(line+"\n")
+            }
+        }
+    }
+
     private fun generateBreakpointList() {
         // builds list of breakpoints, appends to monitor list file
         val breakpoints = mutableListOf<String>()
-        val pattern = Regex("""al (\w+) \S+_prog8_breakpoint_\d+.?""")      // gather breakpoints by the source label that"s generated for them
-        for(line in File(viceMonListFile).readLines()) {
+        val pattern = Regex("""al (\w+) \S+_prog8_breakpoint_\d+.?""")      // gather breakpoints by the source label that's generated for them
+        for (line in viceMonListFile.toFile().readLines()) {
             val match = pattern.matchEntire(line)
-            if(match!=null)
-            breakpoints.add("break \$" + match.groupValues[1])
+            if (match != null)
+                breakpoints.add("break \$" + match.groupValues[1])
         }
         val num = breakpoints.size
         breakpoints.add(0, "; vice monitor breakpoint list now follows")
         breakpoints.add(1, "; $num breakpoints have been defined")
         breakpoints.add(2, "del")
-        File(viceMonListFile).appendText(breakpoints.joinToString("\n")+"\n")
+        viceMonListFile.toFile().appendText(breakpoints.joinToString("\n") + "\n")
     }
 }

compiler/src/prog8/compiler/target/c64/C64MachineDefinition.kt

@@ -4,18 +4,16 @@ import prog8.compiler.CompilationOptions
 import prog8.compiler.CompilerException
 import prog8.compiler.Zeropage
 import prog8.compiler.ZeropageType
-import java.awt.Color
-import java.awt.image.BufferedImage
-import javax.imageio.ImageIO
+import prog8.compiler.target.IMachineDefinition
 import kotlin.math.absoluteValue
 import kotlin.math.pow
 
-object MachineDefinition {
+object C64MachineDefinition: IMachineDefinition {
 
     // 5-byte cbm MFLPT format limitations:
-    const val FLOAT_MAX_POSITIVE = 1.7014118345e+38         // bytes: 255,127,255,255,255
-    const val FLOAT_MAX_NEGATIVE = -1.7014118345e+38        // bytes: 255,255,255,255,255
-
+    override val FLOAT_MAX_POSITIVE = 1.7014118345e+38         // bytes: 255,127,255,255,255
+    override val FLOAT_MAX_NEGATIVE = -1.7014118345e+38        // bytes: 255,255,255,255,255
+    override val FLOAT_MEM_SIZE = 5
     const val BASIC_LOAD_ADDRESS = 0x0801
     const val RAW_LOAD_ADDRESS = 0xc000
 
@@ -30,6 +28,19 @@ object MachineDefinition {
     const val ESTACK_HI_PLUS1_HEX   = "\$cf01"
     const val ESTACK_HI_PLUS2_HEX   = "\$cf02"
 
+    override fun getZeropage(compilerOptions: CompilationOptions) = C64Zeropage(compilerOptions)
+
+    // 6502 opcodes (including aliases and illegal opcodes), these cannot be used as variable or label names
+    override val opcodeNames = setOf("adc", "ahx", "alr", "anc", "and", "ane", "arr", "asl", "asr", "axs", "bcc", "bcs",
+            "beq", "bge", "bit", "blt", "bmi", "bne", "bpl", "brk", "bvc", "bvs", "clc",
+            "cld", "cli", "clv", "cmp", "cpx", "cpy", "dcm", "dcp", "dec", "dex", "dey",
+            "eor", "gcc", "gcs", "geq", "gge", "glt", "gmi", "gne", "gpl", "gvc", "gvs",
+            "inc", "ins", "inx", "iny", "isb", "isc", "jam", "jmp", "jsr", "lae", "las",
+            "lax", "lda", "lds", "ldx", "ldy", "lsr", "lxa", "nop", "ora", "pha", "php",
+            "pla", "plp", "rla", "rol", "ror", "rra", "rti", "rts", "sax", "sbc", "sbx",
+            "sec", "sed", "sei", "sha", "shl", "shr", "shs", "shx", "shy", "slo", "sre",
+            "sta", "stx", "sty", "tas", "tax", "tay", "tsx", "txa", "txs", "tya", "xaa")
+
 
     class C64Zeropage(options: CompilationOptions) : Zeropage(options) {
 
@@ -110,8 +121,6 @@ object MachineDefinition {
     data class Mflpt5(val b0: Short, val b1: Short, val b2: Short, val b3: Short, val b4: Short) {
 
         companion object {
-            const val MemorySize = 5
-
             val zero = Mflpt5(0, 0, 0, 0, 0)
             fun fromNumber(num: Number): Mflpt5 {
                 // see https://en.wikipedia.org/wiki/Microsoft_Binary_Format
@@ -165,91 +174,4 @@ object MachineDefinition {
             return if (sign) -result else result
         }
     }
-
-    object Charset {
-        private val normalImg = ImageIO.read(javaClass.getResource("/charset/c64/charset-normal.png"))
-        private val shiftedImg = ImageIO.read(javaClass.getResource("/charset/c64/charset-shifted.png"))
-
-        private fun scanChars(img: BufferedImage): Array<BufferedImage> {
-
-            val transparent = BufferedImage(img.width, img.height, BufferedImage.TYPE_INT_ARGB)
-            transparent.createGraphics().drawImage(img, 0, 0, null)
-
-            val black = Color(0, 0, 0).rgb
-            val nopixel = Color(0, 0, 0, 0).rgb
-            for (y in 0 until transparent.height) {
-                for (x in 0 until transparent.width) {
-                    val col = transparent.getRGB(x, y)
-                    if (col == black)
-                        transparent.setRGB(x, y, nopixel)
-                }
-            }
-
-            val numColumns = transparent.width / 8
-            val charImages = (0..255).map {
-                val charX = it % numColumns
-                val charY = it / numColumns
-                transparent.getSubimage(charX * 8, charY * 8, 8, 8)
-            }
-            return charImages.toTypedArray()
-        }
-
-        val normalChars = scanChars(normalImg)
-        val shiftedChars = scanChars(shiftedImg)
-
-        private val coloredNormalChars = mutableMapOf<Short, Array<BufferedImage>>()
-
-        fun getColoredChar(screenCode: Short, color: Short): BufferedImage {
-            val colorIdx = (color % colorPalette.size).toShort()
-            val chars = coloredNormalChars[colorIdx]
-            if (chars != null)
-                return chars[screenCode.toInt()]
-
-            val coloredChars = mutableListOf<BufferedImage>()
-            val transparent = Color(0, 0, 0, 0).rgb
-            val rgb = colorPalette[colorIdx.toInt()].rgb
-            for (c in normalChars) {
-                val colored = c.copy()
-                for (y in 0 until colored.height)
-                    for (x in 0 until colored.width) {
-                        if (colored.getRGB(x, y) != transparent) {
-                            colored.setRGB(x, y, rgb)
-                        }
-                    }
-                coloredChars.add(colored)
-            }
-            coloredNormalChars[colorIdx] = coloredChars.toTypedArray()
-            return coloredNormalChars.getValue(colorIdx)[screenCode.toInt()]
-        }
-
-    }
-
-    private fun BufferedImage.copy(): BufferedImage {
-        val bcopy = BufferedImage(this.width, this.height, this.type)
-        val g = bcopy.graphics
-        g.drawImage(this, 0, 0, null)
-        g.dispose()
-        return bcopy
-    }
-
-
-    val colorPalette = listOf(         // this is Pepto's Commodore-64 palette  http://www.pepto.de/projects/colorvic/
-            Color(0x000000),  // 0 = black
-            Color(0xFFFFFF),  // 1 = white
-            Color(0x813338),  // 2 = red
-            Color(0x75cec8),  // 3 = cyan
-            Color(0x8e3c97),  // 4 = purple
-            Color(0x56ac4d),  // 5 = green
-            Color(0x2e2c9b),  // 6 = blue
-            Color(0xedf171),  // 7 = yellow
-            Color(0x8e5029),  // 8 = orange
-            Color(0x553800),  // 9 = brown
-            Color(0xc46c71),  // 10 = light red
-            Color(0x4a4a4a),  // 11 = dark grey
-            Color(0x7b7b7b),  // 12 = medium grey
-            Color(0xa9ff9f),  // 13 = light green
-            Color(0x706deb),  // 14 = light blue
-            Color(0xb2b2b2)   // 15 = light grey
-    )
-
 }

compiler/src/prog8/compiler/target/c64/Petscii.kt

@@ -1058,7 +1058,7 @@ object Petscii {
                 0.toShort()
             else {
                 val case = if (lowercase) "lower" else "upper"
-                throw CharConversionException("no ${case}case Petscii character for '$it'")
+                throw CharConversionException("no ${case}case Petscii character for '$it' (${it.toShort()})")
             }
         }
     }
@@ -1076,7 +1076,7 @@ object Petscii {
                 0.toShort()
             else {
                 val case = if (lowercase) "lower" else "upper"
-                throw CharConversionException("no ${case}Screencode character for '$it'")
+                throw CharConversionException("no ${case}Screencode character for '$it' (${it.toShort()})")
             }
         }
     }

compiler/src/prog8/compiler/target/c64/codegen/AsmOptimizer.kt

@@ -1,7 +1,7 @@
-package prog8.compiler.target.c64.codegen2
+package prog8.compiler.target.c64.codegen
 
-import prog8.compiler.target.c64.MachineDefinition.ESTACK_LO_HEX
-import prog8.compiler.target.c64.MachineDefinition.ESTACK_LO_PLUS1_HEX
+import prog8.compiler.target.c64.C64MachineDefinition.ESTACK_LO_HEX
+import prog8.compiler.target.c64.C64MachineDefinition.ESTACK_LO_PLUS1_HEX
 
 
 // note: see https://wiki.nesdev.com/w/index.php/6502_assembly_optimisations
@@ -13,53 +13,70 @@ fun optimizeAssembly(lines: MutableList<String>): Int {
 
     var linesByFour = getLinesBy(lines, 4)
 
-    var removeLines = optimizeUselessStackByteWrites(linesByFour)
-    if(removeLines.isNotEmpty()) {
-        for (i in removeLines.reversed())
-            lines.removeAt(i)
+    var mods = optimizeUselessStackByteWrites(linesByFour)
+    if(mods.isNotEmpty()) {
+        apply(mods, lines)
         linesByFour = getLinesBy(lines, 4)
         numberOfOptimizations++
     }
 
-    removeLines = optimizeIncDec(linesByFour)
-    if(removeLines.isNotEmpty()) {
-        for (i in removeLines.reversed())
-            lines.removeAt(i)
+    mods = optimizeIncDec(linesByFour)
+    if(mods.isNotEmpty()) {
+        apply(mods, lines)
         linesByFour = getLinesBy(lines, 4)
         numberOfOptimizations++
     }
 
-    removeLines = optimizeCmpSequence(linesByFour)
-    if(removeLines.isNotEmpty()) {
-        for (i in removeLines.reversed())
-            lines.removeAt(i)
+    mods = optimizeCmpSequence(linesByFour)
+    if(mods.isNotEmpty()) {
+        apply(mods, lines)
         linesByFour = getLinesBy(lines, 4)
         numberOfOptimizations++
     }
 
-    removeLines = optimizeStoreLoadSame(linesByFour)
-    if(removeLines.isNotEmpty()) {
-        for (i in removeLines.reversed())
-            lines.removeAt(i)
+    mods = optimizeStoreLoadSame(linesByFour)
+    if(mods.isNotEmpty()) {
+        apply(mods, lines)
+        linesByFour = getLinesBy(lines, 4)
+        numberOfOptimizations++
+    }
+
+    mods= optimizeJsrRts(linesByFour)
+    if(mods.isNotEmpty()) {
+        apply(mods, lines)
         linesByFour = getLinesBy(lines, 4)
         numberOfOptimizations++
     }
 
     var linesByFourteen = getLinesBy(lines, 14)
-    removeLines = optimizeSameAssignments(linesByFourteen)
-    if(removeLines.isNotEmpty()) {
-        for (i in removeLines.reversed())
-            lines.removeAt(i)
+    mods = optimizeSameAssignments(linesByFourteen)
+    if(mods.isNotEmpty()) {
+        apply(mods, lines)
         linesByFourteen = getLinesBy(lines, 14)
         numberOfOptimizations++
     }
 
-    // TODO more assembly optimizations?
+    // TODO more assembly optimizations
 
     return numberOfOptimizations
 }
 
-fun optimizeCmpSequence(linesByFour: List<List<IndexedValue<String>>>): List<Int> {
+private class Modification(val lineIndex: Int, val remove: Boolean, val replacement: String?)
+
+private fun apply(modifications: List<Modification>, lines: MutableList<String>) {
+    for (modification in modifications.sortedBy { it.lineIndex }.reversed()) {
+        if(modification.remove)
+            lines.removeAt(modification.lineIndex)
+        else
+            lines[modification.lineIndex] = modification.replacement!!
+    }
+}
+
+private fun getLinesBy(lines: MutableList<String>, windowSize: Int) =
+// all lines (that aren't empty or comments) in sliding windows of certain size
+        lines.withIndex().filter { it.value.isNotBlank() && !it.value.trimStart().startsWith(';') }.windowed(windowSize, partialWindows = false)
+
+private fun optimizeCmpSequence(linesByFour: List<List<IndexedValue<String>>>): List<Modification> {
     // the when statement (on bytes) generates a sequence of:
     //	 lda $ce01,x
     //	 cmp #$20
@@ -68,42 +85,42 @@ fun optimizeCmpSequence(linesByFour: List<List<IndexedValue<String>>>): List<Int
     //	 cmp #$21
     //	 beq  check_prog8_s73choice_33
     // the repeated lda can be removed
-    val removeLines = mutableListOf<Int>()
+    val mods = mutableListOf<Modification>()
     for(lines in linesByFour) {
         if(lines[0].value.trim()=="lda  $ESTACK_LO_PLUS1_HEX,x" &&
                 lines[1].value.trim().startsWith("cmp ") &&
                 lines[2].value.trim().startsWith("beq ") &&
                 lines[3].value.trim()=="lda  $ESTACK_LO_PLUS1_HEX,x") {
-            removeLines.add(lines[3].index) // remove the second lda
+            mods.add(Modification(lines[3].index, true, null)) // remove the second lda
         }
     }
-    return removeLines
+    return mods
 }
 
-fun optimizeUselessStackByteWrites(linesByFour: List<List<IndexedValue<String>>>): List<Int> {
+private fun optimizeUselessStackByteWrites(linesByFour: List<List<IndexedValue<String>>>): List<Modification> {
     // sta on stack, dex, inx, lda from stack -> eliminate this useless stack byte write
     // this is a lot harder for word values because the instruction sequence varies.
-    val removeLines = mutableListOf<Int>()
+    val mods = mutableListOf<Modification>()
     for(lines in linesByFour) {
         if(lines[0].value.trim()=="sta  $ESTACK_LO_HEX,x" &&
                 lines[1].value.trim()=="dex" &&
                 lines[2].value.trim()=="inx" &&
                 lines[3].value.trim()=="lda  $ESTACK_LO_HEX,x") {
-            removeLines.add(lines[1].index)
-            removeLines.add(lines[2].index)
-            removeLines.add(lines[3].index)
+            mods.add(Modification(lines[1].index, true, null))
+            mods.add(Modification(lines[2].index, true, null))
+            mods.add(Modification(lines[3].index, true, null))
         }
     }
-    return removeLines
+    return mods
 }
 
-fun optimizeSameAssignments(linesByFourteen: List<List<IndexedValue<String>>>): List<Int> {
+private fun optimizeSameAssignments(linesByFourteen: List<List<IndexedValue<String>>>): List<Modification> {
 
     // optimize sequential assignments of the isSameAs value to various targets (bytes, words, floats)
     // the float one is the one that requires 2*7=14 lines of code to check...
-    // @todo a better place to do this is in the Compiler instead and work on opcodes, and never even create the inefficient asm...
+    // @todo a better place to do this is in the Compiler instead and transform the Ast, or the AsmGen, and never even create the inefficient asm in the first place...
 
-    val removeLines = mutableListOf<Int>()
+    val mods = mutableListOf<Modification>()
     for (pair in linesByFourteen) {
         val first = pair[0].value.trimStart()
         val second = pair[1].value.trimStart()
@@ -122,8 +139,8 @@ fun optimizeSameAssignments(linesByFourteen: List<List<IndexedValue<String>>>):
             val fourthvalue = sixth.substring(4)
             if(firstvalue==thirdvalue && secondvalue==fourthvalue) {
                 // lda/ldy   sta/sty   twice the isSameAs word -->  remove second lda/ldy pair (fifth and sixth lines)
-                removeLines.add(pair[4].index)
-                removeLines.add(pair[5].index)
+                mods.add(Modification(pair[4].index, true, null))
+                mods.add(Modification(pair[5].index, true, null))
             }
         }
 
@@ -132,7 +149,7 @@ fun optimizeSameAssignments(linesByFourteen: List<List<IndexedValue<String>>>):
             val secondvalue = third.substring(4)
             if(firstvalue==secondvalue) {
                 // lda value / sta ? / lda isSameAs-value / sta ?  -> remove second lda (third line)
-                removeLines.add(pair[2].index)
+                mods.add(Modification(pair[2].index, true, null))
             }
         }
 
@@ -151,24 +168,20 @@ fun optimizeSameAssignments(linesByFourteen: List<List<IndexedValue<String>>>):
 
                 if(first.substring(4) == eighth.substring(4) && second.substring(4)==nineth.substring(4)) {
                     // identical float init
-                    removeLines.add(pair[7].index)
-                    removeLines.add(pair[8].index)
-                    removeLines.add(pair[9].index)
-                    removeLines.add(pair[10].index)
+                    mods.add(Modification(pair[7].index, true, null))
+                    mods.add(Modification(pair[8].index, true, null))
+                    mods.add(Modification(pair[9].index, true, null))
+                    mods.add(Modification(pair[10].index, true, null))
                 }
             }
         }
     }
-    return removeLines
+    return mods
 }
 
-private fun getLinesBy(lines: MutableList<String>, windowSize: Int) =
-// all lines (that aren't empty or comments) in sliding windows of certain size
-        lines.withIndex().filter { it.value.isNotBlank() && !it.value.trimStart().startsWith(';') }.windowed(windowSize, partialWindows = false)
-
-private fun optimizeStoreLoadSame(linesByFour: List<List<IndexedValue<String>>>): List<Int> {
+private fun optimizeStoreLoadSame(linesByFour: List<List<IndexedValue<String>>>): List<Modification> {
     // sta X + lda X,  sty X + ldy X,   stx X + ldx X  -> the second instruction can be eliminated
-    val removeLines = mutableListOf<Int>()
+    val mods = mutableListOf<Modification>()
     for (pair in linesByFour) {
         val first = pair[0].value.trimStart()
         val second = pair[1].value.trimStart()
@@ -186,26 +199,40 @@ private fun optimizeStoreLoadSame(linesByFour: List<List<IndexedValue<String>>>)
             val firstLoc = first.substring(4)
             val secondLoc = second.substring(4)
             if (firstLoc == secondLoc) {
-                removeLines.add(pair[1].index)
+                mods.add(Modification(pair[1].index, true, null))
             }
         }
     }
-    return removeLines
+    return mods
 }
 
-private fun optimizeIncDec(linesByTwo: List<List<IndexedValue<String>>>): List<Int> {
+private fun optimizeIncDec(linesByFour: List<List<IndexedValue<String>>>): List<Modification> {
     // sometimes, iny+dey / inx+dex / dey+iny / dex+inx sequences are generated, these can be eliminated.
-    val removeLines = mutableListOf<Int>()
-    for (pair in linesByTwo) {
+    val mods = mutableListOf<Modification>()
+    for (pair in linesByFour) {
         val first = pair[0].value
         val second = pair[1].value
         if ((" iny" in first || "\tiny" in first) && (" dey" in second || "\tdey" in second)
                 || (" inx" in first || "\tinx" in first) && (" dex" in second || "\tdex" in second)
                 || (" dey" in first || "\tdey" in first) && (" iny" in second || "\tiny" in second)
                 || (" dex" in first || "\tdex" in first) && (" inx" in second || "\tinx" in second)) {
-            removeLines.add(pair[0].index)
-            removeLines.add(pair[1].index)
+            mods.add(Modification(pair[0].index, true, null))
+            mods.add(Modification(pair[1].index, true, null))
         }
     }
-    return removeLines
+    return mods
+}
+
+private fun optimizeJsrRts(linesByFour: List<List<IndexedValue<String>>>): List<Modification> {
+    // jsr Sub + rts -> jmp Sub
+    val mods = mutableListOf<Modification>()
+    for (pair in linesByFour) {
+        val first = pair[0].value
+        val second = pair[1].value
+        if ((" jsr" in first || "\tjsr" in first ) && (" rts" in second || "\trts" in second)) {
+            mods += Modification(pair[0].index, false, pair[0].value.replace("jsr", "jmp"))
+            mods += Modification(pair[1].index, true, null)
+        }
+    }
+    return mods
 }

compiler/src/prog8/compiler/target/c64/codegen/AssignmentAsmGen.kt

@@ -0,0 +1,675 @@
+package prog8.compiler.target.c64.codegen
+
+import prog8.ast.Program
+import prog8.ast.base.*
+import prog8.ast.expressions.*
+import prog8.ast.statements.AssignTarget
+import prog8.ast.statements.Assignment
+import prog8.ast.statements.DirectMemoryWrite
+import prog8.ast.statements.VarDecl
+import prog8.compiler.AssemblyError
+import prog8.compiler.target.c64.C64MachineDefinition
+import prog8.compiler.target.c64.C64MachineDefinition.C64Zeropage
+import prog8.compiler.target.c64.C64MachineDefinition.ESTACK_HI_HEX
+import prog8.compiler.target.c64.C64MachineDefinition.ESTACK_LO_HEX
+import prog8.compiler.toHex
+
+
+internal class AssignmentAsmGen(private val program: Program, private val asmgen: AsmGen) {
+
+    internal fun translate(assign: Assignment) {
+        if(assign.isInplace)
+            translateNormalAssignment(assign) // TODO generate better code here for in-place assignments
+        else
+            translateNormalAssignment(assign)
+    }
+
+    //  old code-generation below:
+    //  eventually, all of this should have been replaced by newer more optimized code.
+    private fun translateNormalAssignment(assign: Assignment) {
+        when (assign.value) {
+            is NumericLiteralValue -> {
+                val numVal = assign.value as NumericLiteralValue
+                when (numVal.type) {
+                    DataType.UBYTE, DataType.BYTE -> assignFromByteConstant(assign.target, numVal.number.toShort())
+                    DataType.UWORD, DataType.WORD -> assignFromWordConstant(assign.target, numVal.number.toInt())
+                    DataType.FLOAT -> assignFromFloatConstant(assign.target, numVal.number.toDouble())
+                    else -> throw AssemblyError("weird numval type")
+                }
+            }
+            is IdentifierReference -> {
+                when (val type = assign.target.inferType(program, assign).typeOrElse(DataType.STRUCT)) {
+                    DataType.UBYTE, DataType.BYTE -> assignFromByteVariable(assign.target, assign.value as IdentifierReference)
+                    DataType.UWORD, DataType.WORD -> assignFromWordVariable(assign.target, assign.value as IdentifierReference)
+                    DataType.FLOAT -> assignFromFloatVariable(assign.target, assign.value as IdentifierReference)
+                    else -> throw AssemblyError("unsupported assignment target type $type")
+                }
+            }
+            is AddressOf -> {
+                val identifier = (assign.value as AddressOf).identifier
+                assignFromAddressOf(assign.target, identifier)
+            }
+            is DirectMemoryRead -> {
+                val read = (assign.value as DirectMemoryRead)
+                when (read.addressExpression) {
+                    is NumericLiteralValue -> {
+                        val address = (read.addressExpression as NumericLiteralValue).number.toInt()
+                        assignFromMemoryByte(assign.target, address, null)
+                    }
+                    is IdentifierReference -> {
+                        assignFromMemoryByte(assign.target, null, read.addressExpression as IdentifierReference)
+                    }
+                    else -> {
+                        throw AssemblyError("missing asm gen for memread assignment into ${assign.target}")
+                    }
+                }
+            }
+            is PrefixExpression -> {
+                // TODO optimize common cases
+                asmgen.translateExpression(assign.value as PrefixExpression)
+                assignFromEvalResult(assign.target)
+            }
+            is BinaryExpression -> {
+                // TODO optimize common cases
+                asmgen.translateExpression(assign.value as BinaryExpression)
+                assignFromEvalResult(assign.target)
+            }
+            is ArrayIndexedExpression -> {
+                // TODO optimize common cases
+                val arrayExpr = assign.value as ArrayIndexedExpression
+                val arrayDt = arrayExpr.identifier.inferType(program).typeOrElse(DataType.STRUCT)
+                val index = arrayExpr.arrayspec.index
+                if (index is NumericLiteralValue) {
+                    // constant array index value
+                    val arrayVarName = asmgen.asmIdentifierName(arrayExpr.identifier)
+                    val indexValue = index.number.toInt() * ArrayElementTypes.getValue(arrayDt).memorySize()
+                    when (arrayDt) {
+                        DataType.STR, DataType.ARRAY_UB, DataType.ARRAY_B ->
+                            asmgen.out("  lda  $arrayVarName+$indexValue |  sta  $ESTACK_LO_HEX,x |  dex")
+                        DataType.ARRAY_UW, DataType.ARRAY_W ->
+                            asmgen.out("  lda  $arrayVarName+$indexValue |  sta  $ESTACK_LO_HEX,x |  lda  $arrayVarName+$indexValue+1 |  sta  $ESTACK_HI_HEX,x | dex")
+                        DataType.ARRAY_F ->
+                            asmgen.out("  lda  #<$arrayVarName+$indexValue |  ldy  #>$arrayVarName+$indexValue |  jsr  c64flt.push_float")
+                        else ->
+                            throw AssemblyError("weird array type")
+                    }
+                } else {
+                    asmgen.translateArrayIndexIntoA(arrayExpr)
+                    asmgen.readAndPushArrayvalueWithIndexA(arrayDt, arrayExpr.identifier)
+                }
+                assignFromEvalResult(assign.target)
+            }
+            is TypecastExpression -> {
+                val cast = assign.value as TypecastExpression
+                val sourceType = cast.expression.inferType(program)
+                val targetType = assign.target.inferType(program, assign)
+                if (sourceType.isKnown && targetType.isKnown &&
+                        (sourceType.typeOrElse(DataType.STRUCT) in ByteDatatypes && targetType.typeOrElse(DataType.STRUCT) in ByteDatatypes) ||
+                        (sourceType.typeOrElse(DataType.STRUCT) in WordDatatypes && targetType.typeOrElse(DataType.STRUCT) in WordDatatypes)) {
+                    // no need for a type cast
+                    assign.value = cast.expression
+                    translate(assign)
+                } else {
+                    asmgen.translateExpression(assign.value as TypecastExpression)
+                    assignFromEvalResult(assign.target)
+                }
+            }
+            is FunctionCall -> {
+                asmgen.translateExpression(assign.value as FunctionCall)
+                assignFromEvalResult(assign.target)
+            }
+            is ArrayLiteralValue, is StringLiteralValue -> throw AssemblyError("no asm gen for string/array assignment  $assign")
+            is RangeExpr -> throw AssemblyError("range expression should have been changed into array values ${assign.value.position}")
+        }
+    }
+
+    internal fun assignFromEvalResult(target: AssignTarget) {
+        val targetIdent = target.identifier
+        when {
+            targetIdent != null -> {
+                val targetName = asmgen.asmIdentifierName(targetIdent)
+                when (val targetDt = targetIdent.inferType(program).typeOrElse(DataType.STRUCT)) {
+                    DataType.UBYTE, DataType.BYTE -> {
+                        asmgen.out(" inx | lda  $ESTACK_LO_HEX,x  | sta  $targetName")
+                    }
+                    DataType.UWORD, DataType.WORD -> {
+                        asmgen.out("""
+                            inx
+                            lda  $ESTACK_LO_HEX,x
+                            sta  $targetName
+                            lda  $ESTACK_HI_HEX,x
+                            sta  $targetName+1
+                        """)
+                    }
+                    DataType.FLOAT -> {
+                        asmgen.out("""
+                            lda  #<$targetName
+                            ldy  #>$targetName
+                            jsr  c64flt.pop_float
+                        """)
+                    }
+                    else -> throw AssemblyError("weird target variable type $targetDt")
+                }
+            }
+            target.memoryAddress != null -> {
+                asmgen.out("  inx  | ldy  $ESTACK_LO_HEX,x")
+                storeRegisterInMemoryAddress(CpuRegister.Y, target.memoryAddress)
+            }
+            target.arrayindexed != null -> {
+                val arrayDt = target.arrayindexed!!.identifier.inferType(program).typeOrElse(DataType.STRUCT)
+                val arrayVarName = asmgen.asmIdentifierName(target.arrayindexed!!.identifier)
+                asmgen.translateExpression(target.arrayindexed!!.arrayspec.index)
+                asmgen.out("  inx |  lda  $ESTACK_LO_HEX,x")
+                popAndWriteArrayvalueWithIndexA(arrayDt, arrayVarName)
+            }
+            else -> throw AssemblyError("weird assignment target $target")
+        }
+    }
+
+    internal fun assignFromAddressOf(target: AssignTarget, name: IdentifierReference) {
+        val targetIdent = target.identifier
+        val targetArrayIdx = target.arrayindexed
+        val struct = name.memberOfStruct(program.namespace)
+        val sourceName = if (struct != null) {
+            // take the address of the first struct member instead
+            val decl = name.targetVarDecl(program.namespace)!!
+            val firstStructMember = struct.nameOfFirstMember()
+            // find the flattened var that belongs to this first struct member
+            val firstVarName = listOf(decl.name, firstStructMember)
+            val firstVar = name.definingScope().lookup(firstVarName, name) as VarDecl
+            firstVar.name
+        } else {
+            asmgen.fixNameSymbols(name.nameInSource.joinToString("."))
+        }
+
+        when {
+            targetIdent != null -> {
+                val targetName = asmgen.asmIdentifierName(targetIdent)
+                asmgen.out("""
+                        lda  #<$sourceName
+                        ldy  #>$sourceName
+                        sta  $targetName
+                        sty  $targetName+1
+                    """)
+            }
+            target.memoryAddress != null -> {
+                throw AssemblyError("no asm gen for assign address $sourceName to memory word $target")
+            }
+            targetArrayIdx != null -> {
+                val index = targetArrayIdx.arrayspec.index
+                val targetName = asmgen.asmIdentifierName(targetArrayIdx.identifier)
+                throw AssemblyError("no asm gen for assign address $sourceName to array $targetName [ $index ]")
+            }
+            else -> throw AssemblyError("no asm gen for assign address $sourceName to $target")
+        }
+    }
+
+    internal fun assignFromWordVariable(target: AssignTarget, variable: IdentifierReference) {
+        val sourceName = asmgen.asmIdentifierName(variable)
+        val targetIdent = target.identifier
+        val targetArrayIdx = target.arrayindexed
+        when {
+            targetIdent != null -> {
+                val targetName = asmgen.asmIdentifierName(targetIdent)
+                asmgen.out("""
+                    lda  $sourceName
+                    ldy  $sourceName+1
+                    sta  $targetName
+                    sty  $targetName+1
+                """)
+            }
+            target.memoryAddress != null -> {
+                throw AssemblyError("no asm gen for assign wordvar $sourceName to memory ${target.memoryAddress}")
+            }
+            targetArrayIdx != null -> {
+                val index = targetArrayIdx.arrayspec.index
+                val targetName = asmgen.asmIdentifierName(targetArrayIdx.identifier)
+                asmgen.out("  lda  $sourceName |  sta  $ESTACK_LO_HEX,x |  lda  $sourceName+1 |  sta  $ESTACK_HI_HEX,x |  dex")
+                asmgen.translateExpression(index)
+                asmgen.out("  inx |  lda  $ESTACK_LO_HEX,x")
+                val arrayDt = targetArrayIdx.identifier.inferType(program).typeOrElse(DataType.STRUCT)
+                popAndWriteArrayvalueWithIndexA(arrayDt, targetName)
+            }
+            else -> throw AssemblyError("no asm gen for assign wordvar to $target")
+        }
+    }
+
+    internal fun assignFromFloatVariable(target: AssignTarget, variable: IdentifierReference) {
+        val sourceName = asmgen.asmIdentifierName(variable)
+        val targetIdent = target.identifier
+        val targetArrayIdx = target.arrayindexed
+        when {
+            targetIdent != null -> {
+                val targetName = asmgen.asmIdentifierName(targetIdent)
+                asmgen.out("""
+                    lda  $sourceName
+                    sta  $targetName
+                    lda  $sourceName+1
+                    sta  $targetName+1
+                    lda  $sourceName+2
+                    sta  $targetName+2
+                    lda  $sourceName+3
+                    sta  $targetName+3
+                    lda  $sourceName+4
+                    sta  $targetName+4
+                """)
+            }
+            targetArrayIdx != null -> {
+                val index = targetArrayIdx.arrayspec.index
+                val targetName = asmgen.asmIdentifierName(targetArrayIdx.identifier)
+                asmgen.out("  lda  #<$sourceName |  ldy  #>$sourceName |  jsr  c64flt.push_float")
+                asmgen.translateExpression(index)
+                asmgen.out("  lda  #<$targetName |  ldy  #>$targetName |  jsr  c64flt.pop_float_to_indexed_var")
+            }
+            else -> throw AssemblyError("no asm gen for assign floatvar to $target")
+        }
+    }
+
+    internal fun assignFromByteVariable(target: AssignTarget, variable: IdentifierReference) {
+        val sourceName = asmgen.asmIdentifierName(variable)
+        val targetIdent = target.identifier
+        val targetArrayIdx = target.arrayindexed
+        when {
+            targetIdent != null -> {
+                val targetName = asmgen.asmIdentifierName(targetIdent)
+                asmgen.out("""
+                    lda  $sourceName
+                    sta  $targetName
+                    """)
+            }
+            targetArrayIdx != null -> {
+                val index = targetArrayIdx.arrayspec.index
+                val targetName = asmgen.asmIdentifierName(targetArrayIdx.identifier)
+                val arrayDt = targetArrayIdx.identifier.inferType(program).typeOrElse(DataType.STRUCT)
+                asmgen.out("  lda  $sourceName |  sta  $ESTACK_LO_HEX,x |  dex")
+                asmgen.translateExpression(index)
+                asmgen.out("  inx |  lda  $ESTACK_LO_HEX,x")
+                popAndWriteArrayvalueWithIndexA(arrayDt, targetName)
+            }
+            target.memoryAddress != null -> {
+                val addressExpr = target.memoryAddress.addressExpression
+                val addressLv = addressExpr as? NumericLiteralValue
+                when {
+                    addressLv != null -> asmgen.out("  lda  $sourceName |  sta  ${addressLv.number.toHex()}")
+                    addressExpr is IdentifierReference -> {
+                        val targetName = asmgen.asmIdentifierName(addressExpr)
+                        asmgen.out("  lda  $sourceName |  sta  $targetName")
+                    }
+                    else -> {
+                        asmgen.translateExpression(addressExpr)
+                        asmgen.out("""
+     inx
+     lda  $ESTACK_LO_HEX,x
+     ldy  $ESTACK_HI_HEX,x
+     sta  (+) +1
+     sty  (+) +2
+     lda  $sourceName
++    sta  ${'$'}ffff      ; modified              
+                            """)
+                    }
+                }
+            }
+            else -> throw AssemblyError("no asm gen for assign bytevar to $target")
+        }
+    }
+
+    internal fun assignFromRegister(target: AssignTarget, register: CpuRegister) {
+        val targetIdent = target.identifier
+        val targetArrayIdx = target.arrayindexed
+        when {
+            targetIdent != null -> {
+                val targetName = asmgen.asmIdentifierName(targetIdent)
+                asmgen.out("  st${register.name.toLowerCase()}  $targetName")
+            }
+            target.memoryAddress != null -> {
+                storeRegisterInMemoryAddress(register, target.memoryAddress)
+            }
+            targetArrayIdx != null -> {
+                val index = targetArrayIdx.arrayspec.index
+                val targetName = asmgen.asmIdentifierName(targetArrayIdx.identifier)
+                when (index) {
+                    is NumericLiteralValue -> {
+                        val memindex = index.number.toInt()
+                        when (register) {
+                            CpuRegister.A -> asmgen.out("  sta  $targetName+$memindex")
+                            CpuRegister.X -> asmgen.out("  stx  $targetName+$memindex")
+                            CpuRegister.Y -> asmgen.out("  sty  $targetName+$memindex")
+                        }
+                    }
+                    is IdentifierReference -> {
+                        when (register) {
+                            CpuRegister.A -> asmgen.out("  sta  ${C64Zeropage.SCRATCH_B1}")
+                            CpuRegister.X -> asmgen.out("  stx  ${C64Zeropage.SCRATCH_B1}")
+                            CpuRegister.Y -> asmgen.out("  sty  ${C64Zeropage.SCRATCH_B1}")
+                        }
+                        asmgen.out("""
+                            lda  ${asmgen.asmIdentifierName(index)}
+                            tay
+                            lda  ${C64Zeropage.SCRATCH_B1}
+                            sta  $targetName,y
+                        """)
+                    }
+                    else -> {
+                        asmgen.saveRegister(register)
+                        asmgen.translateExpression(index)
+                        asmgen.restoreRegister(register)
+                        when (register) {
+                            CpuRegister.A -> asmgen.out("  sta  ${C64Zeropage.SCRATCH_B1}")
+                            CpuRegister.X -> asmgen.out("  stx  ${C64Zeropage.SCRATCH_B1}")
+                            CpuRegister.Y -> asmgen.out("  sty  ${C64Zeropage.SCRATCH_B1}")
+                        }
+                        asmgen.out("""
+                            inx
+                            lda  $ESTACK_LO_HEX,x
+                            tay
+                            lda  ${C64Zeropage.SCRATCH_B1}
+                            sta  $targetName,y  
+                        """)
+                    }
+                }
+            }
+            else -> throw AssemblyError("no asm gen for assign register $register to $target")
+        }
+    }
+
+    private fun storeRegisterInMemoryAddress(register: CpuRegister, memoryAddress: DirectMemoryWrite) {
+        val addressExpr = memoryAddress.addressExpression
+        val addressLv = addressExpr as? NumericLiteralValue
+        val registerName = register.name.toLowerCase()
+        when {
+            addressLv != null -> asmgen.out("  st$registerName  ${addressLv.number.toHex()}")
+            addressExpr is IdentifierReference -> {
+                val targetName = asmgen.asmIdentifierName(addressExpr)
+                when (register) {
+                    CpuRegister.A -> asmgen.out("""
+        ldy  $targetName
+        sty  (+) +1
+        ldy  $targetName+1
+        sty  (+) +2
++       sta  ${'$'}ffff     ; modified""")
+                    CpuRegister.X -> asmgen.out("""
+        ldy  $targetName
+        sty  (+) +1
+        ldy  $targetName+1
+        sty  (+) +2
++       stx  ${'$'}ffff    ; modified""")
+                    CpuRegister.Y -> asmgen.out("""
+        lda  $targetName
+        sta  (+) +1
+        lda  $targetName+1
+        sta  (+) +2
++       sty  ${'$'}ffff    ; modified""")
+                }
+            }
+            else -> {
+                asmgen.saveRegister(register)
+                asmgen.translateExpression(addressExpr)
+                asmgen.restoreRegister(register)
+                when (register) {
+                    CpuRegister.A -> asmgen.out("  tay")
+                    CpuRegister.X -> throw AssemblyError("can't use X register here")
+                    CpuRegister.Y -> {}
+                }
+                asmgen.out("""
+     inx
+     lda  $ESTACK_LO_HEX,x
+     sta  (+) +1
+     lda  $ESTACK_HI_HEX,x
+     sta  (+) +2
++    sty  ${'$'}ffff      ; modified              
+                            """)
+            }
+        }
+    }
+
+    internal fun assignFromWordConstant(target: AssignTarget, word: Int) {
+        val targetIdent = target.identifier
+        val targetArrayIdx = target.arrayindexed
+        when {
+            targetIdent != null -> {
+                val targetName = asmgen.asmIdentifierName(targetIdent)
+                if (word ushr 8 == word and 255) {
+                    // lsb=msb
+                    asmgen.out("""
+                    lda  #${(word and 255).toHex()}
+                    sta  $targetName
+                    sta  $targetName+1
+                """)
+                } else {
+                    asmgen.out("""
+                    lda  #<${word.toHex()}
+                    ldy  #>${word.toHex()}
+                    sta  $targetName
+                    sty  $targetName+1
+                """)
+                }
+            }
+            target.memoryAddress != null -> {
+                throw AssemblyError("no asm gen for assign word $word to memory ${target.memoryAddress}")
+            }
+            targetArrayIdx != null -> {
+                val index = targetArrayIdx.arrayspec.index
+                val targetName = asmgen.asmIdentifierName(targetArrayIdx.identifier)
+                // TODO optimize common cases
+                asmgen.translateExpression(index)
+                asmgen.out("""
+                    inx
+                    lda  $ESTACK_LO_HEX,x
+                    asl  a
+                    tay
+                    lda  #<${word.toHex()}
+                    sta  $targetName,y
+                    lda  #>${word.toHex()}
+                    sta  $targetName+1,y
+                """)
+            }
+            else -> throw AssemblyError("no asm gen for assign word $word to $target")
+        }
+    }
+
+    internal fun assignFromByteConstant(target: AssignTarget, byte: Short) {
+        val targetIdent = target.identifier
+        val targetArrayIdx = target.arrayindexed
+        when {
+            targetIdent != null -> {
+                val targetName = asmgen.asmIdentifierName(targetIdent)
+                asmgen.out(" lda  #${byte.toHex()} |  sta  $targetName ")
+            }
+            target.memoryAddress != null -> {
+                asmgen.out("  ldy  #${byte.toHex()}")
+                storeRegisterInMemoryAddress(CpuRegister.Y, target.memoryAddress)
+            }
+            targetArrayIdx != null -> {
+                val index = targetArrayIdx.arrayspec.index
+                val targetName = asmgen.asmIdentifierName(targetArrayIdx.identifier)
+                // TODO optimize common cases
+                asmgen.translateExpression(index)
+                asmgen.out("""
+                    inx
+                    ldy  $ESTACK_LO_HEX,x
+                    lda  #${byte.toHex()}
+                    sta  $targetName,y
+                """)
+            }
+            else -> throw AssemblyError("no asm gen for assign byte $byte to $target")
+        }
+    }
+
+    internal fun assignFromFloatConstant(target: AssignTarget, float: Double) {
+        val targetIdent = target.identifier
+        val targetArrayIdx = target.arrayindexed
+        if (float == 0.0) {
+            // optimized case for float zero
+            when {
+                targetIdent != null -> {
+                    val targetName = asmgen.asmIdentifierName(targetIdent)
+                    asmgen.out("""
+                            lda  #0
+                            sta  $targetName
+                            sta  $targetName+1
+                            sta  $targetName+2
+                            sta  $targetName+3
+                            sta  $targetName+4
+                        """)
+                }
+                targetArrayIdx != null -> {
+                    val index = targetArrayIdx.arrayspec.index
+                    val targetName = asmgen.asmIdentifierName(targetArrayIdx.identifier)
+                    if (index is NumericLiteralValue) {
+                        val indexValue = index.number.toInt() * C64MachineDefinition.FLOAT_MEM_SIZE
+                        asmgen.out("""
+                            lda  #0
+                            sta  $targetName+$indexValue
+                            sta  $targetName+$indexValue+1
+                            sta  $targetName+$indexValue+2
+                            sta  $targetName+$indexValue+3
+                            sta  $targetName+$indexValue+4
+                        """)
+                    } else {
+                        asmgen.translateExpression(index)
+                        asmgen.out("""
+                            lda  #<${targetName}
+                            sta  ${C64Zeropage.SCRATCH_W1}
+                            lda  #>${targetName}
+                            sta  ${C64Zeropage.SCRATCH_W1 + 1}
+                            jsr  c64flt.set_0_array_float
+                        """)
+                    }
+                }
+                else -> throw AssemblyError("no asm gen for assign float 0.0 to $target")
+            }
+        } else {
+            // non-zero value
+            val constFloat = asmgen.getFloatConst(float)
+            when {
+                targetIdent != null -> {
+                    val targetName = asmgen.asmIdentifierName(targetIdent)
+                    asmgen.out("""
+                            lda  $constFloat
+                            sta  $targetName
+                            lda  $constFloat+1
+                            sta  $targetName+1
+                            lda  $constFloat+2
+                            sta  $targetName+2
+                            lda  $constFloat+3
+                            sta  $targetName+3
+                            lda  $constFloat+4
+                            sta  $targetName+4
+                        """)
+                }
+                targetArrayIdx != null -> {
+                    val index = targetArrayIdx.arrayspec.index
+                    val arrayVarName = asmgen.asmIdentifierName(targetArrayIdx.identifier)
+                    if (index is NumericLiteralValue) {
+                        val indexValue = index.number.toInt() * C64MachineDefinition.FLOAT_MEM_SIZE
+                        asmgen.out("""
+                            lda  $constFloat
+                            sta  $arrayVarName+$indexValue
+                            lda  $constFloat+1
+                            sta  $arrayVarName+$indexValue+1
+                            lda  $constFloat+2
+                            sta  $arrayVarName+$indexValue+2
+                            lda  $constFloat+3
+                            sta  $arrayVarName+$indexValue+3
+                            lda  $constFloat+4
+                            sta  $arrayVarName+$indexValue+4
+                        """)
+                    } else {
+                        asmgen.translateExpression(index)
+                        asmgen.out("""
+                            lda  #<${constFloat}
+                            sta  ${C64Zeropage.SCRATCH_W1}
+                            lda  #>${constFloat}
+                            sta  ${C64Zeropage.SCRATCH_W1 + 1}
+                            lda  #<${arrayVarName}
+                            sta  ${C64Zeropage.SCRATCH_W2}
+                            lda  #>${arrayVarName}
+                            sta  ${C64Zeropage.SCRATCH_W2 + 1}
+                            jsr  c64flt.set_array_float
+                        """)
+                    }
+                }
+                else -> throw AssemblyError("no asm gen for assign float $float to $target")
+            }
+        }
+    }
+
+    internal fun assignFromMemoryByte(target: AssignTarget, address: Int?, identifier: IdentifierReference?) {
+        val targetIdent = target.identifier
+        val targetArrayIdx = target.arrayindexed
+        if (address != null) {
+            when {
+                targetIdent != null -> {
+                    val targetName = asmgen.asmIdentifierName(targetIdent)
+                    asmgen.out("""
+                        lda  ${address.toHex()}
+                        sta  $targetName
+                        """)
+                }
+                target.memoryAddress != null -> {
+                    asmgen.out("  ldy  ${address.toHex()}")
+                    storeRegisterInMemoryAddress(CpuRegister.Y, target.memoryAddress)
+                }
+                targetArrayIdx != null -> {
+                    val index = targetArrayIdx.arrayspec.index
+                    val targetName = asmgen.asmIdentifierName(targetArrayIdx.identifier)
+                    throw AssemblyError("no asm gen for assign memory byte at $address to array $targetName [ $index ]")
+                }
+                else -> throw AssemblyError("no asm gen for assign memory byte $target")
+            }
+        } else if (identifier != null) {
+            val sourceName = asmgen.asmIdentifierName(identifier)
+            when {
+                targetIdent != null -> {
+                    val targetName = asmgen.asmIdentifierName(targetIdent)
+                    asmgen.out("""
+    lda  $sourceName
+    sta  (+) + 1
+    lda  $sourceName+1
+    sta  (+) + 2
++   lda  ${'$'}ffff\t; modified
+    sta  $targetName""")
+                }
+                target.memoryAddress != null -> {
+                    asmgen.out("  ldy  $sourceName")
+                    storeRegisterInMemoryAddress(CpuRegister.Y, target.memoryAddress)
+                }
+                targetArrayIdx != null -> {
+                    val index = targetArrayIdx.arrayspec.index
+                    val targetName = asmgen.asmIdentifierName(targetArrayIdx.identifier)
+                    throw AssemblyError("no asm gen for assign memory byte $sourceName to array $targetName [ $index ]")
+                }
+                else -> throw AssemblyError("no asm gen for assign memory byte $target")
+            }
+        }
+    }
+
+    private fun popAndWriteArrayvalueWithIndexA(arrayDt: DataType, variablename: String) {
+        when (arrayDt) {
+            DataType.STR, DataType.ARRAY_UB, DataType.ARRAY_B ->
+                asmgen.out("  tay |  inx |  lda  $ESTACK_LO_HEX,x  | sta  $variablename,y")
+            DataType.ARRAY_UW, DataType.ARRAY_W ->
+                asmgen.out("  asl  a |  tay |  inx |  lda  $ESTACK_LO_HEX,x |  sta  $variablename,y |  lda  $ESTACK_HI_HEX,x |  sta $variablename+1,y")
+            DataType.ARRAY_F ->
+                // index * 5 is done in the subroutine that's called
+                asmgen.out("""
+                    sta  $ESTACK_LO_HEX,x
+                    dex
+                    lda  #<$variablename
+                    ldy  #>$variablename
+                    jsr  c64flt.pop_float_to_indexed_var
+                """)
+            else ->
+                throw AssemblyError("weird array type")
+        }
+    }
+
+    fun assignToRegister(reg: CpuRegister, value: Short?, identifier: IdentifierReference?) {
+        if(value!=null) {
+            asmgen.out("  ld${reg.toString().toLowerCase()}  #${value.toHex()}")
+        } else if(identifier!=null) {
+            val name = asmgen.asmIdentifierName(identifier)
+            asmgen.out("  ld${reg.toString().toLowerCase()}  $name")
+        }
+    }
+}

compiler/src/prog8/compiler/target/c64/codegen/BuiltinFunctionsAsmGen.kt

@@ -0,0 +1,630 @@
+package prog8.compiler.target.c64.codegen
+
+import prog8.ast.IFunctionCall
+import prog8.ast.Program
+import prog8.ast.base.*
+import prog8.ast.expressions.*
+import prog8.ast.statements.FunctionCallStatement
+import prog8.compiler.AssemblyError
+import prog8.compiler.target.c64.C64MachineDefinition.C64Zeropage
+import prog8.compiler.target.c64.C64MachineDefinition.ESTACK_HI_HEX
+import prog8.compiler.target.c64.C64MachineDefinition.ESTACK_HI_PLUS1_HEX
+import prog8.compiler.target.c64.C64MachineDefinition.ESTACK_LO_HEX
+import prog8.compiler.target.c64.C64MachineDefinition.ESTACK_LO_PLUS1_HEX
+import prog8.compiler.toHex
+import prog8.functions.FSignature
+
+internal class BuiltinFunctionsAsmGen(private val program: Program, private val asmgen: AsmGen) {
+
+    internal fun translateFunctioncallExpression(fcall: FunctionCall, func: FSignature) {
+        translateFunctioncall(fcall, func, false)
+    }
+
+    internal fun translateFunctioncallStatement(fcall: FunctionCallStatement, func: FSignature) {
+        translateFunctioncall(fcall, func, true)
+    }
+
+    private fun translateFunctioncall(fcall: IFunctionCall, func: FSignature, discardResult: Boolean) {
+        val functionName = fcall.target.nameInSource.last()
+        if (discardResult) {
+            if (func.pure)
+                return  // can just ignore the whole function call altogether
+            else if (func.returntype != null)
+                throw AssemblyError("discarding result of non-pure function $fcall")
+        }
+
+        when (functionName) {
+            "msb" -> funcMsb(fcall)
+            "mkword" -> funcMkword(fcall, func)
+            "abs" -> funcAbs(fcall, func)
+            "swap" -> funcSwap(fcall)
+            "strlen" -> funcStrlen(fcall)
+            "min", "max", "sum" -> funcMinMaxSum(fcall, functionName)
+            "any", "all" -> funcAnyAll(fcall, functionName)
+            "sgn" -> funcSgn(fcall, func)
+            "sin", "cos", "tan", "atan",
+            "ln", "log2", "sqrt", "rad",
+            "deg", "round", "floor", "ceil",
+            "rdnf" -> funcVariousFloatFuncs(fcall, func, functionName)
+            "lsl" -> funcLsl(fcall)
+            "lsr" -> funcLsr(fcall)
+            "rol" -> funcRol(fcall)
+            "rol2" -> funcRol2(fcall)
+            "ror" -> funcRor(fcall)
+            "ror2" -> funcRor2(fcall)
+            "sort" -> funcSort(fcall)
+            "reverse" -> funcReverse(fcall)
+            "rsave" -> {
+                // save cpu status flag and all registers A, X, Y.
+                // see http://6502.org/tutorials/register_preservation.html
+                asmgen.out(" php |  sta  ${C64Zeropage.SCRATCH_REG} | pha  | txa  | pha  | tya  | pha  | lda  ${C64Zeropage.SCRATCH_REG}")
+            }
+            "rrestore" -> {
+                // restore all registers and cpu status flag
+                asmgen.out(" pla |  tay |  pla |  tax |  pla |  plp")
+            }
+            "clear_carry" -> asmgen.out("  clc")
+            "set_carry" -> asmgen.out("  sec")
+            "clear_irqd" -> asmgen.out("  cli")
+            "set_irqd" -> asmgen.out("  sei")
+            else -> {
+                translateFunctionArguments(fcall.args, func)
+                asmgen.out("  jsr  prog8_lib.func_$functionName")
+            }
+        }
+    }
+
+    private fun funcReverse(fcall: IFunctionCall) {
+        val variable = fcall.args.single()
+        if (variable is IdentifierReference) {
+            val decl = variable.targetVarDecl(program.namespace)!!
+            val varName = asmgen.asmIdentifierName(variable)
+            val numElements = decl.arraysize!!.size()
+            when (decl.datatype) {
+                DataType.ARRAY_UB, DataType.ARRAY_B -> {
+                    asmgen.out("""
+                                    lda  #<$varName
+                                    ldy  #>$varName
+                                    sta  ${C64Zeropage.SCRATCH_W1}
+                                    sty  ${C64Zeropage.SCRATCH_W1 + 1}
+                                    lda  #$numElements
+                                    jsr  prog8_lib.reverse_b
+                                """)
+                }
+                DataType.ARRAY_UW, DataType.ARRAY_W -> {
+                    asmgen.out("""
+                                    lda  #<$varName
+                                    ldy  #>$varName
+                                    sta  ${C64Zeropage.SCRATCH_W1}
+                                    sty  ${C64Zeropage.SCRATCH_W1 + 1}
+                                    lda  #$numElements
+                                    jsr  prog8_lib.reverse_w
+                                """)
+                }
+                DataType.ARRAY_F -> {
+                    asmgen.out("""
+                                    lda  #<$varName
+                                    ldy  #>$varName
+                                    sta  ${C64Zeropage.SCRATCH_W1}
+                                    sty  ${C64Zeropage.SCRATCH_W1 + 1}
+                                    lda  #$numElements
+                                    jsr  prog8_lib.reverse_f
+                                """)
+                }
+                else -> throw AssemblyError("weird type")
+            }
+        }
+    }
+
+    private fun funcSort(fcall: IFunctionCall) {
+        val variable = fcall.args.single()
+        if (variable is IdentifierReference) {
+            val decl = variable.targetVarDecl(program.namespace)!!
+            val varName = asmgen.asmIdentifierName(variable)
+            val numElements = decl.arraysize!!.size()
+            when (decl.datatype) {
+                DataType.ARRAY_UB, DataType.ARRAY_B -> {
+                    asmgen.out("""
+                                    lda  #<$varName
+                                    ldy  #>$varName
+                                    sta  ${C64Zeropage.SCRATCH_W1}
+                                    sty  ${C64Zeropage.SCRATCH_W1 + 1}
+                                    lda  #$numElements
+                                    sta  ${C64Zeropage.SCRATCH_B1}
+                                """)
+                    asmgen.out(if (decl.datatype == DataType.ARRAY_UB) "  jsr  prog8_lib.sort_ub" else "  jsr  prog8_lib.sort_b")
+                }
+                DataType.ARRAY_UW, DataType.ARRAY_W -> {
+                    asmgen.out("""
+                                    lda  #<$varName
+                                    ldy  #>$varName
+                                    sta  ${C64Zeropage.SCRATCH_W1}
+                                    sty  ${C64Zeropage.SCRATCH_W1 + 1}
+                                    lda  #$numElements
+                                    sta  ${C64Zeropage.SCRATCH_B1}
+                                """)
+                    asmgen.out(if (decl.datatype == DataType.ARRAY_UW) "  jsr  prog8_lib.sort_uw" else "  jsr  prog8_lib.sort_w")
+                }
+                DataType.ARRAY_F -> throw AssemblyError("sorting of floating point array is not supported")
+                else -> throw AssemblyError("weird type")
+            }
+        } else
+            throw AssemblyError("weird type")
+    }
+
+    private fun funcRor2(fcall: IFunctionCall) {
+        val what = fcall.args.single()
+        val dt = what.inferType(program)
+        when (dt.typeOrElse(DataType.STRUCT)) {
+            DataType.UBYTE -> {
+                when (what) {
+                    is ArrayIndexedExpression -> {
+                        asmgen.translateExpression(what.identifier)
+                        asmgen.translateExpression(what.arrayspec.index)
+                        asmgen.out("  jsr  prog8_lib.ror2_array_ub")
+                    }
+                    is DirectMemoryRead -> {
+                        if (what.addressExpression is NumericLiteralValue) {
+                            val number = (what.addressExpression as NumericLiteralValue).number
+                            asmgen.out("  lda  ${number.toHex()} |  lsr  a |  bcc  + |  ora  #\$80 |+  |  sta  ${number.toHex()}")
+                        } else {
+                            asmgen.translateExpression(what.addressExpression)
+                            asmgen.out("  jsr  prog8_lib.ror2_mem_ub")
+                        }
+                    }
+                    is IdentifierReference -> {
+                        val variable = asmgen.asmIdentifierName(what)
+                        asmgen.out("  lda  $variable |  lsr  a |  bcc  + |  ora  #\$80 |+  |  sta  $variable")
+                    }
+                    else -> throw AssemblyError("weird type")
+                }
+            }
+            DataType.UWORD -> {
+                when (what) {
+                    is ArrayIndexedExpression -> {
+                        asmgen.translateExpression(what.identifier)
+                        asmgen.translateExpression(what.arrayspec.index)
+                        asmgen.out("  jsr  prog8_lib.ror2_array_uw")
+                    }
+                    is IdentifierReference -> {
+                        val variable = asmgen.asmIdentifierName(what)
+                        asmgen.out("  lsr  $variable+1 |  ror  $variable |  bcc  + |  lda  $variable+1 |  ora  #\$80 |  sta  $variable+1 |+  ")
+                    }
+                    else -> throw AssemblyError("weird type")
+                }
+            }
+            else -> throw AssemblyError("weird type")
+        }
+    }
+
+    private fun funcRor(fcall: IFunctionCall) {
+        val what = fcall.args.single()
+        val dt = what.inferType(program)
+        when (dt.typeOrElse(DataType.STRUCT)) {
+            DataType.UBYTE -> {
+                when (what) {
+                    is ArrayIndexedExpression -> {
+                        asmgen.translateExpression(what.identifier)
+                        asmgen.translateExpression(what.arrayspec.index)
+                        asmgen.out("  jsr  prog8_lib.ror_array_ub")
+                    }
+                    is DirectMemoryRead -> {
+                        if (what.addressExpression is NumericLiteralValue) {
+                            val number = (what.addressExpression as NumericLiteralValue).number
+                            asmgen.out("  ror  ${number.toHex()}")
+                        } else {
+                            asmgen.translateExpression(what.addressExpression)
+                            asmgen.out("""
+                        inx
+                        lda  $ESTACK_LO_HEX,x
+                        sta  (+) + 1
+                        lda  $ESTACK_HI_HEX,x
+                        sta  (+) + 2
+    +                   ror  ${'$'}ffff            ; modified                    
+                                        """)
+                        }
+                    }
+                    is IdentifierReference -> {
+                        val variable = asmgen.asmIdentifierName(what)
+                        asmgen.out("  ror  $variable")
+                    }
+                    else -> throw AssemblyError("weird type")
+                }
+            }
+            DataType.UWORD -> {
+                when (what) {
+                    is ArrayIndexedExpression -> {
+                        asmgen.translateExpression(what.identifier)
+                        asmgen.translateExpression(what.arrayspec.index)
+                        asmgen.out("  jsr  prog8_lib.ror_array_uw")
+                    }
+                    is IdentifierReference -> {
+                        val variable = asmgen.asmIdentifierName(what)
+                        asmgen.out("  ror  $variable+1 |  ror  $variable")
+                    }
+                    else -> throw AssemblyError("weird type")
+                }
+            }
+            else -> throw AssemblyError("weird type")
+        }
+    }
+
+    private fun funcRol2(fcall: IFunctionCall) {
+        val what = fcall.args.single()
+        val dt = what.inferType(program)
+        when (dt.typeOrElse(DataType.STRUCT)) {
+            DataType.UBYTE -> {
+                when (what) {
+                    is ArrayIndexedExpression -> {
+                        asmgen.translateExpression(what.identifier)
+                        asmgen.translateExpression(what.arrayspec.index)
+                        asmgen.out("  jsr  prog8_lib.rol2_array_ub")
+                    }
+                    is DirectMemoryRead -> {
+                        if (what.addressExpression is NumericLiteralValue) {
+                            val number = (what.addressExpression as NumericLiteralValue).number
+                            asmgen.out("  lda  ${number.toHex()} |  cmp  #\$80 |  rol  a |  sta  ${number.toHex()}")
+                        } else {
+                            asmgen.translateExpression(what.addressExpression)
+                            asmgen.out("  jsr  prog8_lib.rol2_mem_ub")
+                        }
+                    }
+                    is IdentifierReference -> {
+                        val variable = asmgen.asmIdentifierName(what)
+                        asmgen.out("  lda  $variable |  cmp  #\$80 |  rol  a |  sta  $variable")
+                    }
+                    else -> throw AssemblyError("weird type")
+                }
+            }
+            DataType.UWORD -> {
+                when (what) {
+                    is ArrayIndexedExpression -> {
+                        asmgen.translateExpression(what.identifier)
+                        asmgen.translateExpression(what.arrayspec.index)
+                        asmgen.out("  jsr  prog8_lib.rol2_array_uw")
+                    }
+                    is IdentifierReference -> {
+                        val variable = asmgen.asmIdentifierName(what)
+                        asmgen.out("  asl  $variable |  rol  $variable+1 |  bcc  + |  inc  $variable |+  ")
+                    }
+                    else -> throw AssemblyError("weird type")
+                }
+            }
+            else -> throw AssemblyError("weird type")
+        }
+    }
+
+    private fun funcRol(fcall: IFunctionCall) {
+        val what = fcall.args.single()
+        val dt = what.inferType(program)
+        when (dt.typeOrElse(DataType.STRUCT)) {
+            DataType.UBYTE -> {
+                when (what) {
+                    is ArrayIndexedExpression -> {
+                        asmgen.translateExpression(what.identifier)
+                        asmgen.translateExpression(what.arrayspec.index)
+                        asmgen.out("  jsr  prog8_lib.rol_array_ub")
+                    }
+                    is DirectMemoryRead -> {
+                        if (what.addressExpression is NumericLiteralValue) {
+                            val number = (what.addressExpression as NumericLiteralValue).number
+                            asmgen.out("  rol  ${number.toHex()}")
+                        } else {
+                            asmgen.translateExpression(what.addressExpression)
+                            asmgen.out("""
+                        inx
+                        lda  $ESTACK_LO_HEX,x
+                        sta  (+) + 1
+                        lda  $ESTACK_HI_HEX,x
+                        sta  (+) + 2
+    +                   rol  ${'$'}ffff            ; modified                    
+                                        """)
+                        }
+                    }
+                    is IdentifierReference -> {
+                        val variable = asmgen.asmIdentifierName(what)
+                        asmgen.out("  rol  $variable")
+                    }
+                    else -> throw AssemblyError("weird type")
+                }
+            }
+            DataType.UWORD -> {
+                when (what) {
+                    is ArrayIndexedExpression -> {
+                        asmgen.translateExpression(what.identifier)
+                        asmgen.translateExpression(what.arrayspec.index)
+                        asmgen.out("  jsr  prog8_lib.rol_array_uw")
+                    }
+                    is IdentifierReference -> {
+                        val variable = asmgen.asmIdentifierName(what)
+                        asmgen.out("  rol  $variable |  rol  $variable+1")
+                    }
+                    else -> throw AssemblyError("weird type")
+                }
+            }
+            else -> throw AssemblyError("weird type")
+        }
+    }
+
+    private fun funcLsr(fcall: IFunctionCall) {
+        val what = fcall.args.single()
+        val dt = what.inferType(program)
+        when (dt.typeOrElse(DataType.STRUCT)) {
+            DataType.UBYTE -> {
+                when (what) {
+                    is IdentifierReference -> asmgen.out("  lsr  ${asmgen.asmIdentifierName(what)}")
+                    is DirectMemoryRead -> {
+                        if (what.addressExpression is NumericLiteralValue) {
+                            val number = (what.addressExpression as NumericLiteralValue).number
+                            asmgen.out("  lsr  ${number.toHex()}")
+                        } else {
+                            asmgen.translateExpression(what.addressExpression)
+                            asmgen.out("""
+                        inx
+                        lda  $ESTACK_LO_HEX,x
+                        sta  (+) + 1
+                        lda  $ESTACK_HI_HEX,x
+                        sta  (+) + 2
+    +                   lsr  ${'$'}ffff            ; modified                    
+                                        """)
+                        }
+                    }
+                    is ArrayIndexedExpression -> {
+                        asmgen.translateExpression(what.identifier)
+                        asmgen.translateExpression(what.arrayspec.index)
+                        asmgen.out("  jsr  prog8_lib.lsr_array_ub")
+                    }
+                    else -> throw AssemblyError("weird type")
+                }
+            }
+            DataType.BYTE -> {
+                when (what) {
+                    is ArrayIndexedExpression -> {
+                        asmgen.translateExpression(what.identifier)
+                        asmgen.translateExpression(what.arrayspec.index)
+                        asmgen.out("  jsr  prog8_lib.lsr_array_b")
+                    }
+                    is IdentifierReference -> {
+                        val variable = asmgen.asmIdentifierName(what)
+                        asmgen.out("  lda  $variable |  asl  a |  ror  $variable")
+                    }
+                    else -> throw AssemblyError("weird type")
+                }
+            }
+            DataType.UWORD -> {
+                when (what) {
+                    is ArrayIndexedExpression -> {
+                        asmgen.translateExpression(what.identifier)
+                        asmgen.translateExpression(what.arrayspec.index)
+                        asmgen.out("  jsr  prog8_lib.lsr_array_uw")
+                    }
+                    is IdentifierReference -> {
+                        val variable = asmgen.asmIdentifierName(what)
+                        asmgen.out(" lsr  $variable+1 |  ror  $variable")
+                    }
+                    else -> throw AssemblyError("weird type")
+                }
+            }
+            DataType.WORD -> {
+                when (what) {
+                    is ArrayIndexedExpression -> {
+                        asmgen.translateExpression(what.identifier)
+                        asmgen.translateExpression(what.arrayspec.index)
+                        asmgen.out("  jsr  prog8_lib.lsr_array_w")
+                    }
+                    is IdentifierReference -> {
+                        val variable = asmgen.asmIdentifierName(what)
+                        asmgen.out("  lda  $variable+1 |  asl a  |  ror  $variable+1 |  ror  $variable")
+                    }
+                    else -> throw AssemblyError("weird type")
+                }
+            }
+            else -> throw AssemblyError("weird type")
+        }
+    }
+
+    private fun funcLsl(fcall: IFunctionCall) {
+        val what = fcall.args.single()
+        val dt = what.inferType(program)
+        when (dt.typeOrElse(DataType.STRUCT)) {
+            in ByteDatatypes -> {
+                when (what) {
+                    is IdentifierReference -> asmgen.out("  asl  ${asmgen.asmIdentifierName(what)}")
+                    is DirectMemoryRead -> {
+                        if (what.addressExpression is NumericLiteralValue) {
+                            val number = (what.addressExpression as NumericLiteralValue).number
+                            asmgen.out("  asl  ${number.toHex()}")
+                        } else {
+                            asmgen.translateExpression(what.addressExpression)
+                            asmgen.out("""
+                        inx
+                        lda  $ESTACK_LO_HEX,x
+                        sta  (+) + 1
+                        lda  $ESTACK_HI_HEX,x
+                        sta  (+) + 2
+    +                   asl  ${'$'}ffff            ; modified                    
+                                        """)
+                        }
+                    }
+                    is ArrayIndexedExpression -> {
+                        asmgen.translateExpression(what.identifier)
+                        asmgen.translateExpression(what.arrayspec.index)
+                        asmgen.out("  jsr  prog8_lib.lsl_array_b")
+                    }
+                    else -> throw AssemblyError("weird type")
+                }
+            }
+            in WordDatatypes -> {
+                when (what) {
+                    is ArrayIndexedExpression -> {
+                        asmgen.translateExpression(what.identifier)
+                        asmgen.translateExpression(what.arrayspec.index)
+                        asmgen.out("  jsr  prog8_lib.lsl_array_w")
+                    }
+                    is IdentifierReference -> {
+                        val variable = asmgen.asmIdentifierName(what)
+                        asmgen.out(" asl  $variable |  rol  $variable+1")
+                    }
+                    else -> throw AssemblyError("weird type")
+                }
+            }
+            else -> throw AssemblyError("weird type")
+        }
+    }
+
+    private fun funcVariousFloatFuncs(fcall: IFunctionCall, func: FSignature, functionName: String) {
+        translateFunctionArguments(fcall.args, func)
+        asmgen.out("  jsr  c64flt.func_$functionName")
+    }
+
+    private fun funcSgn(fcall: IFunctionCall, func: FSignature) {
+        translateFunctionArguments(fcall.args, func)
+        val dt = fcall.args.single().inferType(program)
+        when (dt.typeOrElse(DataType.STRUCT)) {
+            DataType.UBYTE -> asmgen.out("  jsr  math.sign_ub")
+            DataType.BYTE -> asmgen.out("  jsr  math.sign_b")
+            DataType.UWORD -> asmgen.out("  jsr  math.sign_uw")
+            DataType.WORD -> asmgen.out("  jsr  math.sign_w")
+            DataType.FLOAT -> asmgen.out("  jsr  c64flt.sign_f")
+            else -> throw AssemblyError("weird type $dt")
+        }
+    }
+
+    private fun funcAnyAll(fcall: IFunctionCall, functionName: String) {
+        outputPushAddressAndLenghtOfArray(fcall.args[0])
+        val dt = fcall.args.single().inferType(program)
+        when (dt.typeOrElse(DataType.STRUCT)) {
+            DataType.ARRAY_B, DataType.ARRAY_UB, DataType.STR -> asmgen.out("  jsr  prog8_lib.func_${functionName}_b")
+            DataType.ARRAY_UW, DataType.ARRAY_W -> asmgen.out("  jsr  prog8_lib.func_${functionName}_w")
+            DataType.ARRAY_F -> asmgen.out("  jsr  c64flt.func_${functionName}_f")
+            else -> throw AssemblyError("weird type $dt")
+        }
+    }
+
+    private fun funcMinMaxSum(fcall: IFunctionCall, functionName: String) {
+        outputPushAddressAndLenghtOfArray(fcall.args[0])
+        val dt = fcall.args.single().inferType(program)
+        when (dt.typeOrElse(DataType.STRUCT)) {
+            DataType.ARRAY_UB, DataType.STR -> asmgen.out("  jsr  prog8_lib.func_${functionName}_ub")
+            DataType.ARRAY_B -> asmgen.out("  jsr  prog8_lib.func_${functionName}_b")
+            DataType.ARRAY_UW -> asmgen.out("  jsr  prog8_lib.func_${functionName}_uw")
+            DataType.ARRAY_W -> asmgen.out("  jsr  prog8_lib.func_${functionName}_w")
+            DataType.ARRAY_F -> asmgen.out("  jsr  c64flt.func_${functionName}_f")
+            else -> throw AssemblyError("weird type $dt")
+        }
+    }
+
+    private fun funcStrlen(fcall: IFunctionCall) {
+        outputPushAddressOfIdentifier(fcall.args[0])
+        asmgen.out("  jsr  prog8_lib.func_strlen")
+    }
+
+    private fun funcSwap(fcall: IFunctionCall) {
+        val first = fcall.args[0]
+        val second = fcall.args[1]
+        if(first is IdentifierReference && second is IdentifierReference) {
+            val firstName = asmgen.asmIdentifierName(first)
+            val secondName = asmgen.asmIdentifierName(second)
+            val dt = first.inferType(program)
+            if(dt.istype(DataType.BYTE) || dt.istype(DataType.UBYTE)) {
+                asmgen.out(" ldy  $firstName |  lda  $secondName |  sta  $firstName |  tya |  sta  $secondName")
+                return
+            }
+            if(dt.istype(DataType.WORD) || dt.istype(DataType.UWORD)) {
+                asmgen.out("""
+                    ldy  $firstName
+                    lda  $secondName
+                    sta  $firstName
+                    sty  $secondName
+                    ldy  $firstName+1
+                    lda  $secondName+1
+                    sta  $firstName+1
+                    sty  $secondName+1
+                """)
+                return
+            }
+            if(dt.istype(DataType.FLOAT)) {
+                asmgen.out("""
+                    lda  #<$firstName
+                    sta  ${C64Zeropage.SCRATCH_W1}
+                    lda  #>$firstName
+                    sta  ${C64Zeropage.SCRATCH_W1+1}
+                    lda  #<$secondName
+                    sta  ${C64Zeropage.SCRATCH_W2}
+                    lda  #>$secondName
+                    sta  ${C64Zeropage.SCRATCH_W2+1}
+                    jsr  c64flt.swap_floats
+                """)
+                return
+            }
+        }
+
+        // other types of swap() calls should have been replaced by a different statement sequence involving a temp variable
+        throw AssemblyError("no asm generation for swap funccall $fcall")
+    }
+
+    private fun funcAbs(fcall: IFunctionCall, func: FSignature) {
+        translateFunctionArguments(fcall.args, func)
+        val dt = fcall.args.single().inferType(program)
+        when (dt.typeOrElse(DataType.STRUCT)) {
+            in ByteDatatypes -> asmgen.out("  jsr  prog8_lib.abs_b")
+            in WordDatatypes -> asmgen.out("  jsr  prog8_lib.abs_w")
+            DataType.FLOAT -> asmgen.out("  jsr  c64flt.abs_f")
+            else -> throw AssemblyError("weird type")
+        }
+    }
+
+    private fun funcMkword(fcall: IFunctionCall, func: FSignature) {
+        translateFunctionArguments(fcall.args, func)
+        asmgen.out("  inx | lda  $ESTACK_LO_HEX,x  | sta  $ESTACK_HI_PLUS1_HEX,x")
+    }
+
+    private fun funcMsb(fcall: IFunctionCall) {
+        val arg = fcall.args.single()
+        if (arg.inferType(program).typeOrElse(DataType.STRUCT) !in WordDatatypes)
+            throw AssemblyError("msb required word argument")
+        if (arg is NumericLiteralValue)
+            throw AssemblyError("should have been const-folded")
+        if (arg is IdentifierReference) {
+            val sourceName = asmgen.asmIdentifierName(arg)
+            asmgen.out("  lda  $sourceName+1 |  sta  $ESTACK_LO_HEX,x |  dex")
+        } else {
+            asmgen.translateExpression(arg)
+            asmgen.out("  lda  $ESTACK_HI_PLUS1_HEX,x |  sta  $ESTACK_LO_PLUS1_HEX,x")
+        }
+    }
+
+    private fun outputPushAddressAndLenghtOfArray(arg: Expression) {
+        arg as IdentifierReference
+        val identifierName = asmgen.asmIdentifierName(arg)
+        val size = arg.targetVarDecl(program.namespace)!!.arraysize!!.size()!!
+        asmgen.out("""
+                    lda  #<$identifierName
+                    sta  $ESTACK_LO_HEX,x
+                    lda  #>$identifierName
+                    sta  $ESTACK_HI_HEX,x
+                    dex
+                    lda  #$size
+                    sta  $ESTACK_LO_HEX,x
+                    dex
+                    """)
+    }
+
+    private fun outputPushAddressOfIdentifier(arg: Expression) {
+        val identifierName = asmgen.asmIdentifierName(arg as IdentifierReference)
+        asmgen.out("""
+                    lda  #<$identifierName
+                    sta  $ESTACK_LO_HEX,x
+                    lda  #>$identifierName
+                    sta  $ESTACK_HI_HEX,x
+                    dex
+                    """)
+    }
+
+    private fun translateFunctionArguments(args: MutableList<Expression>, signature: FSignature) {
+        args.forEach {
+            asmgen.translateExpression(it)
+        }
+    }
+
+}

compiler/src/prog8/compiler/target/c64/codegen/ExpressionsAsmGen.kt

@@ -0,0 +1,499 @@
+package prog8.compiler.target.c64.codegen
+
+import prog8.ast.Program
+import prog8.ast.base.*
+import prog8.ast.expressions.*
+import prog8.compiler.AssemblyError
+import prog8.compiler.target.c64.C64MachineDefinition
+import prog8.compiler.target.c64.C64MachineDefinition.ESTACK_HI_HEX
+import prog8.compiler.target.c64.C64MachineDefinition.ESTACK_HI_PLUS1_HEX
+import prog8.compiler.target.c64.C64MachineDefinition.ESTACK_LO_HEX
+import prog8.compiler.target.c64.C64MachineDefinition.ESTACK_LO_PLUS1_HEX
+import prog8.compiler.target.c64.C64MachineDefinition.ESTACK_LO_PLUS2_HEX
+import prog8.compiler.toHex
+import prog8.functions.BuiltinFunctions
+import kotlin.math.absoluteValue
+
+internal class ExpressionsAsmGen(private val program: Program, private val asmgen: AsmGen) {
+
+    internal fun translateExpression(expression: Expression) {
+        when(expression) {
+            is PrefixExpression -> translateExpression(expression)
+            is BinaryExpression -> translateExpression(expression)
+            is ArrayIndexedExpression -> translatePushFromArray(expression)
+            is TypecastExpression -> translateExpression(expression)
+            is AddressOf -> translateExpression(expression)
+            is DirectMemoryRead -> translateExpression(expression)
+            is NumericLiteralValue -> translateExpression(expression)
+            is IdentifierReference -> translateExpression(expression)
+            is FunctionCall -> translateExpression(expression)
+            is ArrayLiteralValue, is StringLiteralValue -> throw AssemblyError("no asm gen for string/array literal value assignment - should have been replaced by a variable")
+            is RangeExpr -> throw AssemblyError("range expression should have been changed into array values")
+        }
+    }
+
+    private fun translateExpression(expression: FunctionCall) {
+        val functionName = expression.target.nameInSource.last()
+        val builtinFunc = BuiltinFunctions[functionName]
+        if (builtinFunc != null) {
+            asmgen.translateFunctioncallExpression(expression, builtinFunc)
+        } else {
+            val sub = expression.target.targetSubroutine(program.namespace)!!
+            asmgen.translateFunctionCall(expression)
+            val returns = sub.returntypes.zip(sub.asmReturnvaluesRegisters)
+            for ((_, reg) in returns) {
+                if (!reg.stack) {
+                    // result value in cpu or status registers, put it on the stack
+                    if (reg.registerOrPair != null) {
+                        when (reg.registerOrPair) {
+                            RegisterOrPair.A -> asmgen.out("  sta  $ESTACK_LO_HEX,x |  dex")
+                            RegisterOrPair.Y -> asmgen.out("  tya |  sta  $ESTACK_LO_HEX,x |  dex")
+                            RegisterOrPair.AY -> asmgen.out("  sta  $ESTACK_LO_HEX,x |  tya |  sta  $ESTACK_HI_HEX,x |  dex")
+                            RegisterOrPair.X -> {
+                                // return value in X register has been discarded, just push a zero
+                                asmgen.out("  lda  #0 |  sta  $ESTACK_LO_HEX,x |  dex")
+                            }
+                            RegisterOrPair.AX -> {
+                                // return value in X register has been discarded, just push a zero in this place
+                                asmgen.out("  sta  $ESTACK_LO_HEX,x |  lda  #0 |  sta  $ESTACK_HI_HEX,x |  dex")
+                            }
+                            RegisterOrPair.XY -> {
+                                // return value in X register has been discarded, just push a zero in this place
+                                asmgen.out("  lda  #0 |  sta  $ESTACK_LO_HEX,x |  tya |  sta  $ESTACK_HI_HEX,x |  dex")
+                            }
+                        }
+                    }
+                    // return value from a statusregister is not put on the stack, it should be acted on via a conditional branch such as if_cc
+                }
+            }
+        }
+    }
+
+    private fun translateExpression(expr: TypecastExpression) {
+        translateExpression(expr.expression)
+        when(expr.expression.inferType(program).typeOrElse(DataType.STRUCT)) {
+            DataType.UBYTE -> {
+                when(expr.type) {
+                    DataType.UBYTE, DataType.BYTE -> {}
+                    DataType.UWORD, DataType.WORD -> asmgen.out("  lda  #0  |  sta  $ESTACK_HI_PLUS1_HEX,x")
+                    DataType.FLOAT -> asmgen.out(" jsr  c64flt.stack_ub2float")
+                    in PassByReferenceDatatypes -> throw AssemblyError("cannot cast to a pass-by-reference datatype")
+                    else -> throw AssemblyError("weird type")
+                }
+            }
+            DataType.BYTE -> {
+                when(expr.type) {
+                    DataType.UBYTE, DataType.BYTE -> {}
+                    DataType.UWORD, DataType.WORD -> asmgen.out("  lda  $ESTACK_LO_PLUS1_HEX,x  |  ${asmgen.signExtendAtoMsb("$ESTACK_HI_PLUS1_HEX,x")}")
+                    DataType.FLOAT -> asmgen.out(" jsr  c64flt.stack_b2float")
+                    in PassByReferenceDatatypes -> throw AssemblyError("cannot cast to a pass-by-reference datatype")
+                    else -> throw AssemblyError("weird type")
+                }
+            }
+            DataType.UWORD -> {
+                when(expr.type) {
+                    DataType.BYTE, DataType.UBYTE -> {}
+                    DataType.WORD, DataType.UWORD -> {}
+                    DataType.FLOAT -> asmgen.out(" jsr  c64flt.stack_uw2float")
+                    in PassByReferenceDatatypes -> throw AssemblyError("cannot cast to a pass-by-reference datatype")
+                    else -> throw AssemblyError("weird type")
+                }
+            }
+            DataType.WORD -> {
+                when(expr.type) {
+                    DataType.BYTE, DataType.UBYTE -> {}
+                    DataType.WORD, DataType.UWORD -> {}
+                    DataType.FLOAT -> asmgen.out(" jsr  c64flt.stack_w2float")
+                    in PassByReferenceDatatypes -> throw AssemblyError("cannot cast to a pass-by-reference datatype")
+                    else -> throw AssemblyError("weird type")
+                }
+            }
+            DataType.FLOAT -> {
+                when(expr.type) {
+                    DataType.UBYTE -> asmgen.out(" jsr  c64flt.stack_float2uw")
+                    DataType.BYTE -> asmgen.out(" jsr  c64flt.stack_float2w")
+                    DataType.UWORD -> asmgen.out(" jsr  c64flt.stack_float2uw")
+                    DataType.WORD -> asmgen.out(" jsr  c64flt.stack_float2w")
+                    DataType.FLOAT -> {}
+                    in PassByReferenceDatatypes -> throw AssemblyError("cannot cast to a pass-by-reference datatype")
+                    else -> throw AssemblyError("weird type")
+                }
+            }
+            in PassByReferenceDatatypes -> throw AssemblyError("cannot cast pass-by-reference value into another type")
+            else -> throw AssemblyError("weird type")
+        }
+    }
+
+    private fun translateExpression(expr: AddressOf) {
+        val name = asmgen.asmIdentifierName(expr.identifier)
+        asmgen.out("  lda  #<$name |  sta  $ESTACK_LO_HEX,x |  lda  #>$name  |  sta  $ESTACK_HI_HEX,x  | dex")
+    }
+
+    private fun translateExpression(expr: DirectMemoryRead) {
+        when(expr.addressExpression) {
+            is NumericLiteralValue -> {
+                val address = (expr.addressExpression as NumericLiteralValue).number.toInt()
+                asmgen.out("  lda  ${address.toHex()} |  sta  $ESTACK_LO_HEX,x |  dex")
+            }
+            is IdentifierReference -> {
+                // the identifier is a pointer variable, so read the value from the address in it
+                val sourceName = asmgen.asmIdentifierName(expr.addressExpression as IdentifierReference)
+                asmgen.out("""
+        lda  $sourceName
+        sta  (+) +1
+        lda  $sourceName+1
+        sta  (+) +2
++       lda  ${'$'}ffff     ; modified
+        sta  $ESTACK_LO_HEX,x
+        dex""")
+            }
+            else -> {
+                translateExpression(expr.addressExpression)
+                asmgen.out("  jsr  prog8_lib.read_byte_from_address")
+                asmgen.out("  sta  $ESTACK_LO_PLUS1_HEX,x")
+            }
+        }
+    }
+
+    private fun translateExpression(expr: NumericLiteralValue) {
+        when(expr.type) {
+            DataType.UBYTE, DataType.BYTE -> asmgen.out(" lda  #${expr.number.toHex()}  | sta  $ESTACK_LO_HEX,x  | dex")
+            DataType.UWORD, DataType.WORD -> asmgen.out("""
+                lda  #<${expr.number.toHex()}
+                sta  $ESTACK_LO_HEX,x
+                lda  #>${expr.number.toHex()}
+                sta  $ESTACK_HI_HEX,x
+                dex
+            """)
+            DataType.FLOAT -> {
+                val floatConst = asmgen.getFloatConst(expr.number.toDouble())
+                asmgen.out(" lda  #<$floatConst |  ldy  #>$floatConst |  jsr  c64flt.push_float")
+            }
+            else -> throw AssemblyError("weird type")
+        }
+    }
+
+    private fun translateExpression(expr: IdentifierReference) {
+        val varname = asmgen.asmIdentifierName(expr)
+        when(expr.inferType(program).typeOrElse(DataType.STRUCT)) {
+            DataType.UBYTE, DataType.BYTE -> {
+                asmgen.out("  lda  $varname  |  sta  $ESTACK_LO_HEX,x  |  dex")
+            }
+            DataType.UWORD, DataType.WORD -> {
+                asmgen.out("  lda  $varname  |  sta  $ESTACK_LO_HEX,x  |  lda  $varname+1 |  sta  $ESTACK_HI_HEX,x |  dex")
+            }
+            DataType.FLOAT -> {
+                asmgen.out(" lda  #<$varname |  ldy  #>$varname|  jsr  c64flt.push_float")
+            }
+            in IterableDatatypes -> {
+                asmgen.out("  lda  #<$varname  |  sta  $ESTACK_LO_HEX,x  |  lda  #>$varname |  sta  $ESTACK_HI_HEX,x |  dex")
+            }
+            else -> throw AssemblyError("stack push weird variable type $expr")
+        }
+    }
+
+    private val optimizedByteMultiplications = setOf(3,5,6,7,9,10,11,12,13,14,15,20,25,40)
+    private val optimizedWordMultiplications = setOf(3,5,6,7,9,10,12,15,20,25,40)
+
+    private fun translateExpression(expr: BinaryExpression) {
+        val leftIDt = expr.left.inferType(program)
+        val rightIDt = expr.right.inferType(program)
+        if(!leftIDt.isKnown || !rightIDt.isKnown)
+            throw AssemblyError("can't infer type of both expression operands")
+
+        val leftDt = leftIDt.typeOrElse(DataType.STRUCT)
+        val rightDt = rightIDt.typeOrElse(DataType.STRUCT)
+        // see if we can apply some optimized routines
+        when(expr.operator) {
+            ">>" -> {
+                // bit-shifts are always by a constant number (for now)
+                translateExpression(expr.left)
+                val amount = expr.right.constValue(program)!!.number.toInt()
+                when (leftDt) {
+                    DataType.UBYTE -> {
+                        if(amount<=2)
+                            repeat(amount) { asmgen.out(" lsr  $ESTACK_LO_PLUS1_HEX,x") }
+                        else {
+                            asmgen.out(" lda  $ESTACK_LO_PLUS1_HEX,x")
+                            repeat(amount) { asmgen.out(" lsr  a") }
+                            asmgen.out(" sta  $ESTACK_LO_PLUS1_HEX,x")
+                        }
+                    }
+                    DataType.BYTE -> {
+                        if(amount<=2)
+                            repeat(amount) { asmgen.out(" lda  $ESTACK_LO_PLUS1_HEX,x |  asl  a |  ror  $ESTACK_LO_PLUS1_HEX,x") }
+                        else {
+                            asmgen.out(" lda  $ESTACK_LO_PLUS1_HEX,x |  sta  ${C64MachineDefinition.C64Zeropage.SCRATCH_B1}")
+                            repeat(amount) { asmgen.out(" asl  a |  ror  ${C64MachineDefinition.C64Zeropage.SCRATCH_B1} |  lda  ${C64MachineDefinition.C64Zeropage.SCRATCH_B1}") }
+                            asmgen.out(" sta  $ESTACK_LO_PLUS1_HEX,x")
+                        }
+                    }
+                    DataType.UWORD -> {
+                        var left = amount
+                        while(left>=7) {
+                            asmgen.out(" jsr  math.shift_right_uw_7")
+                            left -= 7
+                        }
+                        if (left in 0..2)
+                            repeat(left) { asmgen.out(" lsr  $ESTACK_HI_PLUS1_HEX,x |  ror  $ESTACK_LO_PLUS1_HEX,x") }
+                        else
+                            asmgen.out(" jsr  math.shift_right_uw_$left")
+                    }
+                    DataType.WORD -> {
+                        var left = amount
+                        while(left>=7) {
+                            asmgen.out(" jsr  math.shift_right_w_7")
+                            left -= 7
+                        }
+                        if (left in 0..2)
+                            repeat(left) { asmgen.out(" lda  $ESTACK_HI_PLUS1_HEX,x |  asl a  |  ror  $ESTACK_HI_PLUS1_HEX,x |  ror  $ESTACK_LO_PLUS1_HEX,x") }
+                        else
+                            asmgen.out(" jsr  math.shift_right_w_$left")
+                    }
+                    else -> throw AssemblyError("weird type")
+                }
+                return
+            }
+            "<<" -> {
+                // bit-shifts are always by a constant number (for now)
+                translateExpression(expr.left)
+                val amount = expr.right.constValue(program)!!.number.toInt()
+                if (leftDt in ByteDatatypes) {
+                    if(amount<=2)
+                        repeat(amount) { asmgen.out("  asl  $ESTACK_LO_PLUS1_HEX,x") }
+                    else {
+                        asmgen.out("  lda  $ESTACK_LO_PLUS1_HEX,x")
+                        repeat(amount) { asmgen.out("  asl  a") }
+                        asmgen.out("  sta  $ESTACK_LO_PLUS1_HEX,x")
+                    }
+                }
+                else {
+                    var left=amount
+                    while(left>=7) {
+                        asmgen.out(" jsr  math.shift_left_w_7")
+                        left -= 7
+                    }
+                    if (left in 0..2)
+                        repeat(left) { asmgen.out("  asl  $ESTACK_LO_PLUS1_HEX,x |  rol  $ESTACK_HI_PLUS1_HEX,x") }
+                    else
+                        asmgen.out(" jsr  math.shift_left_w_$left")
+                }
+                return
+            }
+            "*" -> {
+                val value = expr.right.constValue(program)
+                if(value!=null) {
+                    if(rightDt in IntegerDatatypes) {
+                        val amount = value.number.toInt()
+                        when(rightDt) {
+                            DataType.UBYTE -> {
+                                if(amount in optimizedByteMultiplications) {
+                                    translateExpression(expr.left)
+                                    asmgen.out(" jsr  math.mul_byte_$amount")
+                                    return
+                                }
+                            }
+                            DataType.BYTE -> {
+                                if(amount in optimizedByteMultiplications) {
+                                    translateExpression(expr.left)
+                                    asmgen.out(" jsr  math.mul_byte_$amount")
+                                    return
+                                }
+                                if(amount.absoluteValue in optimizedByteMultiplications) {
+                                    translateExpression(expr.left)
+                                    asmgen.out(" jsr  prog8_lib.neg_b |  jsr  math.mul_byte_${amount.absoluteValue}")
+                                    return
+                                }
+                            }
+                            DataType.UWORD -> {
+                                if(amount in optimizedWordMultiplications) {
+                                    translateExpression(expr.left)
+                                    asmgen.out(" jsr  math.mul_word_$amount")
+                                    return
+                                }
+                            }
+                            DataType.WORD -> {
+                                if(amount in optimizedWordMultiplications) {
+                                    translateExpression(expr.left)
+                                    asmgen.out(" jsr  math.mul_word_$amount")
+                                    return
+                                }
+                                if(amount.absoluteValue in optimizedWordMultiplications) {
+                                    translateExpression(expr.left)
+                                    asmgen.out(" jsr  prog8_lib.neg_w |  jsr  math.mul_word_${amount.absoluteValue}")
+                                    return
+                                }
+                            }
+                            else -> {}
+                        }
+                    }
+                }
+            }
+        }
+
+        // the general, non-optimized cases
+        translateExpression(expr.left)
+        translateExpression(expr.right)
+        if((leftDt in ByteDatatypes && rightDt !in ByteDatatypes)
+                || (leftDt in WordDatatypes && rightDt !in WordDatatypes))
+            throw AssemblyError("binary operator ${expr.operator} left/right dt not identical")
+
+        when (leftDt) {
+            in ByteDatatypes -> translateBinaryOperatorBytes(expr.operator, leftDt)
+            in WordDatatypes -> translateBinaryOperatorWords(expr.operator, leftDt)
+            DataType.FLOAT -> translateBinaryOperatorFloats(expr.operator)
+            else -> throw AssemblyError("non-numerical datatype")
+        }
+    }
+
+    private fun translateExpression(expr: PrefixExpression) {
+        translateExpression(expr.expression)
+        val type = expr.inferType(program).typeOrElse(DataType.STRUCT)
+        when(expr.operator) {
+            "+" -> {}
+            "-" -> {
+                when(type) {
+                    in ByteDatatypes -> asmgen.out("  jsr  prog8_lib.neg_b")
+                    in WordDatatypes -> asmgen.out("  jsr  prog8_lib.neg_w")
+                    DataType.FLOAT -> asmgen.out("  jsr  c64flt.neg_f")
+                    else -> throw AssemblyError("weird type")
+                }
+            }
+            "~" -> {
+                when(type) {
+                    in ByteDatatypes ->
+                        asmgen.out("""
+                            lda  $ESTACK_LO_PLUS1_HEX,x
+                            eor  #255
+                            sta  $ESTACK_LO_PLUS1_HEX,x
+                            """)
+                    in WordDatatypes -> asmgen.out("  jsr  prog8_lib.inv_word")
+                    else -> throw AssemblyError("weird type")
+                }
+            }
+            "not" -> {
+                when(type) {
+                    in ByteDatatypes -> asmgen.out("  jsr  prog8_lib.not_byte")
+                    in WordDatatypes -> asmgen.out("  jsr  prog8_lib.not_word")
+                    else -> throw AssemblyError("weird type")
+                }
+            }
+            else -> throw AssemblyError("invalid prefix operator ${expr.operator}")
+        }
+    }
+
+    private fun translatePushFromArray(arrayExpr: ArrayIndexedExpression) {
+        // assume *reading* from an array
+        val index = arrayExpr.arrayspec.index
+        val arrayDt = arrayExpr.identifier.targetVarDecl(program.namespace)!!.datatype
+        val arrayVarName = asmgen.asmIdentifierName(arrayExpr.identifier)
+        if(index is NumericLiteralValue) {
+            val elementDt = ArrayElementTypes.getValue(arrayDt)
+            val indexValue = index.number.toInt() * elementDt.memorySize()
+            when(elementDt) {
+                in ByteDatatypes -> {
+                    asmgen.out("  lda  $arrayVarName+$indexValue |  sta  $ESTACK_LO_HEX,x |  dex")
+                }
+                in WordDatatypes -> {
+                    asmgen.out("  lda  $arrayVarName+$indexValue |  sta  $ESTACK_LO_HEX,x |  lda  $arrayVarName+$indexValue+1 |  sta  $ESTACK_HI_HEX,x |  dex")
+                }
+                DataType.FLOAT -> {
+                    asmgen.out("  lda  #<$arrayVarName+$indexValue |  ldy  #>$arrayVarName+$indexValue |  jsr  c64flt.push_float")
+                }
+                else -> throw AssemblyError("weird type")
+            }
+        } else {
+            asmgen.translateArrayIndexIntoA(arrayExpr)
+            asmgen.readAndPushArrayvalueWithIndexA(arrayDt, arrayExpr.identifier)
+        }
+    }
+
+    private fun translateBinaryOperatorBytes(operator: String, types: DataType) {
+        when(operator) {
+            "**" -> throw AssemblyError("** operator requires floats")
+            "*" -> asmgen.out("  jsr  prog8_lib.mul_byte")  //  the optimized routines should have been checked earlier
+            "/" -> asmgen.out(if(types==DataType.UBYTE) "  jsr  prog8_lib.idiv_ub" else "  jsr  prog8_lib.idiv_b")
+            "%" -> {
+                if(types==DataType.BYTE)
+                    throw AssemblyError("remainder of signed integers is not properly defined/implemented, use unsigned instead")
+                asmgen.out("  jsr prog8_lib.remainder_ub")
+            }
+            "+" -> asmgen.out("""
+                lda  $ESTACK_LO_PLUS2_HEX,x
+                clc
+                adc  $ESTACK_LO_PLUS1_HEX,x
+                inx
+                sta  $ESTACK_LO_PLUS1_HEX,x
+                """)
+            "-" -> asmgen.out("""
+                lda  $ESTACK_LO_PLUS2_HEX,x
+                sec
+                sbc  $ESTACK_LO_PLUS1_HEX,x
+                inx
+                sta  $ESTACK_LO_PLUS1_HEX,x
+                """)
+            "<<", ">>" -> throw AssemblyError("bit-shifts not via stack")
+            "<" -> asmgen.out(if(types==DataType.UBYTE) "  jsr  prog8_lib.less_ub" else "  jsr  prog8_lib.less_b")
+            ">" -> asmgen.out(if(types==DataType.UBYTE) "  jsr  prog8_lib.greater_ub" else "  jsr  prog8_lib.greater_b")
+            "<=" -> asmgen.out(if(types==DataType.UBYTE) "  jsr  prog8_lib.lesseq_ub" else "  jsr  prog8_lib.lesseq_b")
+            ">=" -> asmgen.out(if(types==DataType.UBYTE) "  jsr  prog8_lib.greatereq_ub" else "  jsr  prog8_lib.greatereq_b")
+            "==" -> asmgen.out("  jsr  prog8_lib.equal_b")
+            "!=" -> asmgen.out("  jsr  prog8_lib.notequal_b")
+            "&" -> asmgen.out("  jsr  prog8_lib.bitand_b")
+            "^" -> asmgen.out("  jsr  prog8_lib.bitxor_b")
+            "|" -> asmgen.out("  jsr  prog8_lib.bitor_b")
+            "and" -> asmgen.out("  jsr  prog8_lib.and_b")
+            "or" -> asmgen.out("  jsr  prog8_lib.or_b")
+            "xor" -> asmgen.out("  jsr  prog8_lib.xor_b")
+            else -> throw AssemblyError("invalid operator $operator")
+        }
+    }
+
+    private fun translateBinaryOperatorWords(operator: String, types: DataType) {
+        when(operator) {
+            "**" -> throw AssemblyError("** operator requires floats")
+            "*" -> asmgen.out("  jsr  prog8_lib.mul_word")
+            "/" -> asmgen.out(if(types==DataType.UWORD) "  jsr  prog8_lib.idiv_uw" else "  jsr  prog8_lib.idiv_w")
+            "%" -> {
+                if(types==DataType.WORD)
+                    throw AssemblyError("remainder of signed integers is not properly defined/implemented, use unsigned instead")
+                asmgen.out("  jsr prog8_lib.remainder_uw")
+            }
+            "+" -> asmgen.out("  jsr  prog8_lib.add_w")
+            "-" -> asmgen.out("  jsr  prog8_lib.sub_w")
+            "<<" -> throw AssemblyError("<< should not operate via stack")
+            ">>" -> throw AssemblyError(">> should not operate via stack")
+            "<" -> asmgen.out(if(types==DataType.UWORD) "  jsr  prog8_lib.less_uw" else "  jsr  prog8_lib.less_w")
+            ">" -> asmgen.out(if(types==DataType.UWORD) "  jsr  prog8_lib.greater_uw" else "  jsr  prog8_lib.greater_w")
+            "<=" -> asmgen.out(if(types==DataType.UWORD) "  jsr  prog8_lib.lesseq_uw" else "  jsr  prog8_lib.lesseq_w")
+            ">=" -> asmgen.out(if(types==DataType.UWORD) "  jsr  prog8_lib.greatereq_uw" else "  jsr  prog8_lib.greatereq_w")
+            "==" -> asmgen.out("  jsr  prog8_lib.equal_w")
+            "!=" -> asmgen.out("  jsr  prog8_lib.notequal_w")
+            "&" -> asmgen.out("  jsr  prog8_lib.bitand_w")
+            "^" -> asmgen.out("  jsr  prog8_lib.bitxor_w")
+            "|" -> asmgen.out("  jsr  prog8_lib.bitor_w")
+            "and" -> asmgen.out("  jsr  prog8_lib.and_w")
+            "or" -> asmgen.out("  jsr  prog8_lib.or_w")
+            "xor" -> asmgen.out("  jsr  prog8_lib.xor_w")
+            else -> throw AssemblyError("invalid operator $operator")
+        }
+    }
+
+    private fun translateBinaryOperatorFloats(operator: String) {
+        when(operator) {
+            "**" -> asmgen.out(" jsr  c64flt.pow_f")
+            "*" -> asmgen.out("  jsr  c64flt.mul_f")
+            "/" -> asmgen.out("  jsr  c64flt.div_f")
+            "+" -> asmgen.out("  jsr  c64flt.add_f")
+            "-" -> asmgen.out("  jsr  c64flt.sub_f")
+            "<" -> asmgen.out("  jsr  c64flt.less_f")
+            ">" -> asmgen.out("  jsr  c64flt.greater_f")
+            "<=" -> asmgen.out("  jsr  c64flt.lesseq_f")
+            ">=" -> asmgen.out("  jsr  c64flt.greatereq_f")
+            "==" -> asmgen.out("  jsr  c64flt.equal_f")
+            "!=" -> asmgen.out("  jsr  c64flt.notequal_f")
+            "%", "<<", ">>", "&", "^", "|", "and", "or", "xor" -> throw AssemblyError("requires integer datatype")
+            else -> throw AssemblyError("invalid operator $operator")
+        }
+    }
+}

compiler/src/prog8/compiler/target/c64/codegen/ForLoopsAsmGen.kt

@@ -0,0 +1,618 @@
+package prog8.compiler.target.c64.codegen
+
+import prog8.ast.Program
+import prog8.ast.base.DataType
+import prog8.ast.expressions.IdentifierReference
+import prog8.ast.expressions.RangeExpr
+import prog8.ast.statements.AssignTarget
+import prog8.ast.statements.Assignment
+import prog8.ast.statements.ForLoop
+import prog8.compiler.AssemblyError
+import prog8.compiler.target.c64.C64MachineDefinition.ESTACK_HI_PLUS1_HEX
+import prog8.compiler.target.c64.C64MachineDefinition.ESTACK_LO_HEX
+import prog8.compiler.target.c64.C64MachineDefinition.ESTACK_LO_PLUS1_HEX
+import prog8.compiler.toHex
+import kotlin.math.absoluteValue
+
+internal class ForLoopsAsmGen(private val program: Program, private val asmgen: AsmGen) {
+
+    internal fun translate(stmt: ForLoop) {
+        val iterableDt = stmt.iterable.inferType(program)
+        if(!iterableDt.isKnown)
+            throw AssemblyError("can't determine iterable dt")
+        when(stmt.iterable) {
+            is RangeExpr -> {
+                val range = (stmt.iterable as RangeExpr).toConstantIntegerRange()
+                if(range==null) {
+                    translateForOverNonconstRange(stmt, iterableDt.typeOrElse(DataType.STRUCT), stmt.iterable as RangeExpr)
+                } else {
+                    translateForOverConstRange(stmt, iterableDt.typeOrElse(DataType.STRUCT), range)
+                }
+            }
+            is IdentifierReference -> {
+                translateForOverIterableVar(stmt, iterableDt.typeOrElse(DataType.STRUCT), stmt.iterable as IdentifierReference)
+            }
+            else -> throw AssemblyError("can't iterate over ${stmt.iterable.javaClass} - should have been replaced by a variable")
+        }
+    }
+
+    private fun translateForOverNonconstRange(stmt: ForLoop, iterableDt: DataType, range: RangeExpr) {
+        val loopLabel = asmgen.makeLabel("for_loop")
+        val endLabel = asmgen.makeLabel("for_end")
+        val modifiedLabel = asmgen.makeLabel("for_modified")
+        val modifiedLabel2 = asmgen.makeLabel("for_modifiedb")
+        asmgen.loopEndLabels.push(endLabel)
+        val stepsize=range.step.constValue(program)!!.number.toInt()
+        when(iterableDt) {
+            DataType.ARRAY_B, DataType.ARRAY_UB -> {
+                if (stepsize==1 || stepsize==-1) {
+
+                    // bytes, step 1 or -1
+
+                    val incdec = if(stepsize==1) "inc" else "dec"
+                    // loop over byte range via loopvar
+                    val varname = asmgen.asmIdentifierName(stmt.loopVar)
+                    asmgen.translateExpression(range.to)
+                    asmgen.translateExpression(range.from)
+                    asmgen.out("""
+                inx
+                lda  $ESTACK_LO_HEX,x
+                sta  $varname
+                lda  $ESTACK_LO_PLUS1_HEX,x
+                sta  $modifiedLabel+1
+$loopLabel""")
+                        asmgen.translate(stmt.body)
+                        asmgen.out("""
+                lda  $varname
+$modifiedLabel  cmp  #0         ; modified 
+                beq  $endLabel
+                $incdec  $varname
+                jmp  $loopLabel
+$endLabel       inx""")
+
+                } else {
+
+                    // bytes, step >= 2 or <= -2
+
+                    // loop over byte range via loopvar
+                    val varname = asmgen.asmIdentifierName(stmt.loopVar)
+                    asmgen.translateExpression(range.to)
+                    asmgen.translateExpression(range.from)
+                    asmgen.out("""
+                inx
+                lda  $ESTACK_LO_HEX,x
+                sta  $varname
+                lda  $ESTACK_LO_PLUS1_HEX,x
+                sta  $modifiedLabel+1
+$loopLabel""")
+                    asmgen.translate(stmt.body)
+                    asmgen.out("""
+                lda  $varname""")
+                    if(stepsize>0) {
+                        asmgen.out("""
+                clc
+                adc  #$stepsize
+                sta  $varname
+$modifiedLabel  cmp  #0    ; modified
+                bcc  $loopLabel
+                beq  $loopLabel""")
+                    } else {
+                        asmgen.out("""
+                sec
+                sbc  #${stepsize.absoluteValue}
+                sta  $varname
+$modifiedLabel  cmp  #0     ; modified 
+                bcs  $loopLabel""")
+                    }
+                    asmgen.out("""
+$endLabel       inx""")
+                }
+            }
+            DataType.ARRAY_W, DataType.ARRAY_UW -> {
+                when {
+
+                    // words, step 1 or -1
+
+                    stepsize == 1 || stepsize == -1 -> {
+                        asmgen.translateExpression(range.to)
+                        val varname = asmgen.asmIdentifierName(stmt.loopVar)
+                        val assignLoopvar = Assignment(AssignTarget(stmt.loopVar, null, null, stmt.loopVar.position), range.from, range.position)
+                        assignLoopvar.linkParents(stmt)
+                        asmgen.translate(assignLoopvar)
+                        asmgen.out("""
+                            lda  $ESTACK_HI_PLUS1_HEX,x
+                            sta  $modifiedLabel+1
+                            lda  $ESTACK_LO_PLUS1_HEX,x
+                            sta  $modifiedLabel2+1
+$loopLabel""")
+                        asmgen.translate(stmt.body)
+                        asmgen.out("""
+                lda  $varname+1
+$modifiedLabel  cmp  #0    ; modified 
+                bne  +
+                lda  $varname
+$modifiedLabel2 cmp  #0    ; modified 
+                beq  $endLabel""")
+                        if(stepsize==1) {
+                            asmgen.out("""
++               inc  $varname
+                bne  $loopLabel
+                inc  $varname+1
+                jmp  $loopLabel
+                            """)
+                        } else {
+                            asmgen.out("""
++               lda  $varname
+                bne  +
+                dec  $varname+1
++               dec  $varname
+                jmp  $loopLabel""")
+                        }
+                        asmgen.out(endLabel)
+                        asmgen.out(" inx")
+                    }
+                    stepsize > 0 -> {
+
+                        // (u)words, step >= 2
+                        asmgen.translateExpression(range.to)
+                        asmgen.out("""
+                            lda  $ESTACK_HI_PLUS1_HEX,x
+                            sta  $modifiedLabel+1
+                            lda  $ESTACK_LO_PLUS1_HEX,x
+                            sta  $modifiedLabel2+1
+                        """)
+                        val varname = asmgen.asmIdentifierName(stmt.loopVar)
+                        val assignLoopvar = Assignment(AssignTarget(stmt.loopVar, null, null, stmt.loopVar.position), range.from, range.position)
+                        assignLoopvar.linkParents(stmt)
+                        asmgen.translate(assignLoopvar)
+                        asmgen.out(loopLabel)
+                        asmgen.translate(stmt.body)
+
+                        if (iterableDt == DataType.ARRAY_UW) {
+                            asmgen.out("""
+                lda  $varname
+                clc
+                adc  #<$stepsize
+                sta  $varname
+                lda  $varname+1
+                adc  #>$stepsize
+                sta  $varname+1
+$modifiedLabel  cmp  #0     ; modified
+                bcc  $loopLabel
+                bne  $endLabel
+$modifiedLabel2 lda  #0     ; modified
+                cmp  $varname
+                bcc  $endLabel
+                bcs  $loopLabel
+$endLabel       inx""")
+                        } else {
+                            asmgen.out("""
+                lda  $varname
+                clc
+                adc  #<$stepsize
+                sta  $varname
+                lda  $varname+1
+                adc  #>$stepsize
+                sta  $varname+1
+$modifiedLabel2 lda  #0   ; modified
+                cmp  $varname
+$modifiedLabel  lda  #0   ; modified
+                sbc  $varname+1
+                bvc  +
+                eor  #$80
++               bpl  $loopLabel                
+$endLabel       inx""")
+                        }
+                    }
+                    else -> {
+
+                        // (u)words, step <= -2
+                        asmgen.translateExpression(range.to)
+                        asmgen.out("""
+                            lda  $ESTACK_HI_PLUS1_HEX,x
+                            sta  $modifiedLabel+1
+                            lda  $ESTACK_LO_PLUS1_HEX,x
+                            sta  $modifiedLabel2+1
+                        """)
+                        val varname = asmgen.asmIdentifierName(stmt.loopVar)
+                        val assignLoopvar = Assignment(AssignTarget(stmt.loopVar, null, null, stmt.loopVar.position), range.from, range.position)
+                        assignLoopvar.linkParents(stmt)
+                        asmgen.translate(assignLoopvar)
+                        asmgen.out(loopLabel)
+                        asmgen.translate(stmt.body)
+
+                        if(iterableDt==DataType.ARRAY_UW) {
+                            asmgen.out("""
+                lda  $varname
+                sec
+                sbc  #<${stepsize.absoluteValue}
+                sta  $varname
+                lda  $varname+1
+                sbc  #>${stepsize.absoluteValue}
+                sta  $varname+1
+$modifiedLabel  cmp  #0    ; modified                
+                bcc  $endLabel
+                bne  $loopLabel
+                lda  $varname
+$modifiedLabel2 cmp  #0    ; modified 
+                bcs  $loopLabel
+$endLabel       inx""")
+                        } else {
+                            asmgen.out("""
+                lda  $varname
+                sec
+                sbc  #<${stepsize.absoluteValue}
+                sta  $varname
+                pha
+                lda  $varname+1
+                sbc  #>${stepsize.absoluteValue}
+                sta  $varname+1
+                pla
+$modifiedLabel2 cmp  #0    ; modified 
+                lda  $varname+1
+$modifiedLabel  sbc  #0    ; modified
+                bvc  +
+                eor  #$80
++               bpl  $loopLabel                
+$endLabel       inx""")
+                        }
+                    }
+                }
+            }
+            else -> throw AssemblyError("range expression can only be byte or word")
+        }
+
+        asmgen.loopEndLabels.pop()
+    }
+
+    private fun translateForOverIterableVar(stmt: ForLoop, iterableDt: DataType, ident: IdentifierReference) {
+        val loopLabel = asmgen.makeLabel("for_loop")
+        val endLabel = asmgen.makeLabel("for_end")
+        asmgen.loopEndLabels.push(endLabel)
+        val iterableName = asmgen.asmIdentifierName(ident)
+        val decl = ident.targetVarDecl(program.namespace)!!
+        when(iterableDt) {
+            DataType.STR -> {
+                asmgen.out("""
+                    lda  #<$iterableName
+                    ldy  #>$iterableName
+                    sta  $loopLabel+1
+                    sty  $loopLabel+2
+$loopLabel          lda  ${65535.toHex()}       ; modified
+                    beq  $endLabel
+                    sta  ${asmgen.asmIdentifierName(stmt.loopVar)}""")
+                asmgen.translate(stmt.body)
+                asmgen.out("""
+                    inc  $loopLabel+1
+                    bne  $loopLabel
+                    inc  $loopLabel+2
+                    bne  $loopLabel
+$endLabel""")
+            }
+            DataType.ARRAY_UB, DataType.ARRAY_B -> {
+                val length = decl.arraysize!!.size()!!
+                val indexVar = asmgen.makeLabel("for_index")
+                asmgen.out("""
+                    ldy  #0
+$loopLabel          sty  $indexVar
+                    lda  $iterableName,y
+                    sta  ${asmgen.asmIdentifierName(stmt.loopVar)}""")
+                asmgen.translate(stmt.body)
+                if(length<=255) {
+                    asmgen.out("""
+                        ldy  $indexVar
+                        iny
+                        cpy  #$length
+                        beq  $endLabel
+                        bne  $loopLabel""")
+                } else {
+                    // length is 256
+                    asmgen.out("""
+                        ldy  $indexVar
+                        iny
+                        bne  $loopLabel
+                        beq  $endLabel""")
+                }
+                if(length>=16 && asmgen.zeropage.available() > 0) {
+                    // allocate index var on ZP
+                    val zpAddr = asmgen.zeropage.allocate(indexVar, DataType.UBYTE, stmt.position, asmgen.errors)
+                    asmgen.out("""$indexVar = $zpAddr  ; auto zp UBYTE""")
+                } else {
+                    asmgen.out("""
+$indexVar           .byte  0""")
+                }
+                asmgen.out(endLabel)
+            }
+            DataType.ARRAY_W, DataType.ARRAY_UW -> {
+                val length = decl.arraysize!!.size()!! * 2
+                val indexVar = asmgen.makeLabel("for_index")
+                val loopvarName = asmgen.asmIdentifierName(stmt.loopVar)
+                asmgen.out("""
+                    ldy  #0
+$loopLabel          sty  $indexVar
+                    lda  $iterableName,y
+                    sta  $loopvarName
+                    lda  $iterableName+1,y
+                    sta  $loopvarName+1""")
+                asmgen.translate(stmt.body)
+                if(length<=127) {
+                    asmgen.out("""
+                        ldy  $indexVar
+                        iny
+                        iny
+                        cpy  #$length
+                        beq  $endLabel
+                        bne  $loopLabel""")
+                } else {
+                    // length is 128 words, 256 bytes
+                    asmgen.out("""
+                        ldy  $indexVar
+                        iny
+                        iny
+                        bne  $loopLabel
+                        beq  $endLabel""")
+                }
+                if(length>=16 && asmgen.zeropage.available() > 0) {
+                    // allocate index var on ZP
+                    val zpAddr = asmgen.zeropage.allocate(indexVar, DataType.UBYTE, stmt.position, asmgen.errors)
+                    asmgen.out("""$indexVar = $zpAddr  ; auto zp UBYTE""")
+                } else {
+                    asmgen.out("""
+$indexVar           .byte  0""")
+                }
+                asmgen.out(endLabel)
+            }
+            DataType.ARRAY_F -> {
+                throw AssemblyError("for loop with floating point variables is not supported")
+            }
+            else -> throw AssemblyError("can't iterate over $iterableDt")
+        }
+        asmgen.loopEndLabels.pop()
+    }
+
+    private fun translateForOverConstRange(stmt: ForLoop, iterableDt: DataType, range: IntProgression) {
+        if (range.isEmpty() || range.step==0)
+            throw AssemblyError("empty range or step 0")
+        if(iterableDt==DataType.ARRAY_B || iterableDt==DataType.ARRAY_UB) {
+            if(range.step==1 && range.last>range.first) return translateForSimpleByteRangeAsc(stmt, range)
+            if(range.step==-1 && range.last<range.first) return translateForSimpleByteRangeDesc(stmt, range)
+        }
+        else if(iterableDt==DataType.ARRAY_W || iterableDt==DataType.ARRAY_UW) {
+            if(range.step==1 && range.last>range.first) return translateForSimpleWordRangeAsc(stmt, range)
+            if(range.step==-1 && range.last<range.first) return translateForSimpleWordRangeDesc(stmt, range)
+        }
+
+        // not one of the easy cases, generate more complex code...
+        val loopLabel = asmgen.makeLabel("for_loop")
+        val endLabel = asmgen.makeLabel("for_end")
+        asmgen.loopEndLabels.push(endLabel)
+        when(iterableDt) {
+            DataType.ARRAY_B, DataType.ARRAY_UB -> {
+                // loop over byte range via loopvar, step >= 2 or <= -2
+                val varname = asmgen.asmIdentifierName(stmt.loopVar)
+                asmgen.out("""
+                            lda  #${range.first}
+                            sta  $varname
+$loopLabel""")
+                asmgen.translate(stmt.body)
+                when (range.step) {
+                    0, 1, -1 -> {
+                        throw AssemblyError("step 0, 1 and -1 should have been handled specifically  $stmt")
+                    }
+                    2 -> {
+                        if(range.last==255) {
+                            asmgen.out("""
+                                inc  $varname
+                                beq  $endLabel
+                                inc  $varname
+                                bne  $loopLabel""")
+                        } else {
+                            asmgen.out("""
+                                lda  $varname
+                                cmp  #${range.last}
+                                beq  $endLabel
+                                inc  $varname
+                                inc  $varname
+                                jmp  $loopLabel""")
+                        }
+                    }
+                    -2 -> {
+                        when (range.last) {
+                            0 -> asmgen.out("""
+                                lda  $varname
+                                beq  $endLabel
+                                dec  $varname
+                                dec  $varname
+                                jmp  $loopLabel""")
+                            1 -> asmgen.out("""
+                                dec  $varname
+                                beq  $endLabel
+                                dec  $varname
+                                bne  $loopLabel""")
+                            else -> asmgen.out("""
+                                lda  $varname
+                                cmp  #${range.last}
+                                beq  $endLabel
+                                dec  $varname
+                                dec  $varname
+                                jmp  $loopLabel""")
+                        }
+                    }
+                    else -> {
+                        // step <= -3 or >= 3
+                        asmgen.out("""
+                            lda  $varname
+                            cmp  #${range.last}
+                            beq  $endLabel
+                            clc
+                            adc  #${range.step}
+                            sta  $varname
+                            jmp  $loopLabel""")
+                    }
+                }
+                asmgen.out(endLabel)
+            }
+            DataType.ARRAY_W, DataType.ARRAY_UW -> {
+                // loop over word range via loopvar, step >= 2 or <= -2
+                val varname = asmgen.asmIdentifierName(stmt.loopVar)
+                when (range.step) {
+                    0, 1, -1 -> {
+                        throw AssemblyError("step 0, 1 and -1 should have been handled specifically  $stmt")
+                    }
+                    else -> {
+                        // word, step >= 2 or <= -2
+                        // note: range.last has already been adjusted by kotlin itself to actually be the last value of the sequence
+                        asmgen.out("""
+                            lda  #<${range.first}
+                            ldy  #>${range.first}
+                            sta  $varname
+                            sty  $varname+1
+$loopLabel""")
+                        asmgen.translate(stmt.body)
+                        asmgen.out("""
+                            lda  $varname
+                            cmp  #<${range.last}
+                            bne  +
+                            lda  $varname+1
+                            cmp  #>${range.last}
+                            bne  +
+                            beq  $endLabel
++                           lda  $varname
+                            clc
+                            adc  #<${range.step}
+                            sta  $varname
+                            lda  $varname+1
+                            adc  #>${range.step}
+                            sta  $varname+1
+                            jmp  $loopLabel
+$endLabel""")
+                    }
+                }
+            }
+            else -> throw AssemblyError("range expression can only be byte or word")
+        }
+        asmgen.loopEndLabels.pop()
+    }
+
+    private fun translateForSimpleByteRangeAsc(stmt: ForLoop, range: IntProgression) {
+        val loopLabel = asmgen.makeLabel("for_loop")
+        val endLabel = asmgen.makeLabel("for_end")
+        asmgen.loopEndLabels.push(endLabel)
+        val varname = asmgen.asmIdentifierName(stmt.loopVar)
+        asmgen.out("""
+                lda  #${range.first}
+                sta  $varname
+$loopLabel""")
+        asmgen.translate(stmt.body)
+        if (range.last == 255) {
+            asmgen.out("""
+                inc  $varname
+                bne  $loopLabel
+$endLabel""")
+        } else {
+            asmgen.out("""
+                lda  $varname
+                cmp  #${range.last}
+                beq  $endLabel
+                inc  $varname
+                jmp  $loopLabel
+$endLabel""")
+        }
+        asmgen.loopEndLabels.pop()
+    }
+
+    private fun translateForSimpleByteRangeDesc(stmt: ForLoop, range: IntProgression) {
+        val loopLabel = asmgen.makeLabel("for_loop")
+        val endLabel = asmgen.makeLabel("for_end")
+        asmgen.loopEndLabels.push(endLabel)
+        val varname = asmgen.asmIdentifierName(stmt.loopVar)
+        asmgen.out("""
+                    lda  #${range.first}
+                    sta  $varname
+$loopLabel""")
+        asmgen.translate(stmt.body)
+        when (range.last) {
+            0 -> {
+                asmgen.out("""
+                    lda  $varname
+                    beq  $endLabel
+                    dec  $varname
+                    jmp  $loopLabel
+$endLabel""")
+            }
+            1 -> {
+                asmgen.out("""
+                    dec  $varname
+                    jmp  $loopLabel
+$endLabel""")
+            }
+            else -> {
+                asmgen.out("""
+                    lda  $varname
+                    cmp  #${range.last}
+                    beq  $endLabel
+                    dec  $varname
+                    jmp  $loopLabel
+$endLabel""")
+            }
+        }
+        asmgen.loopEndLabels.pop()
+    }
+
+    private fun translateForSimpleWordRangeAsc(stmt: ForLoop, range: IntProgression) {
+        val loopLabel = asmgen.makeLabel("for_loop")
+        val endLabel = asmgen.makeLabel("for_end")
+        asmgen.loopEndLabels.push(endLabel)
+        val varname = asmgen.asmIdentifierName(stmt.loopVar)
+        asmgen.out("""
+            lda  #<${range.first}
+            ldy  #>${range.first}
+            sta  $varname
+            sty  $varname+1
+$loopLabel""")
+        asmgen.translate(stmt.body)
+        asmgen.out("""
+            lda  $varname
+            cmp  #<${range.last}
+            bne  +
+            lda  $varname+1
+            cmp  #>${range.last}
+            bne  +
+            beq  $endLabel
++           inc  $varname
+            bne  $loopLabel
+            inc  $varname+1
+            jmp  $loopLabel
+$endLabel""")
+        asmgen.loopEndLabels.pop()
+    }
+
+    private fun translateForSimpleWordRangeDesc(stmt: ForLoop, range: IntProgression) {
+        val loopLabel = asmgen.makeLabel("for_loop")
+        val endLabel = asmgen.makeLabel("for_end")
+        asmgen.loopEndLabels.push(endLabel)
+        val varname = asmgen.asmIdentifierName(stmt.loopVar)
+        asmgen.out("""
+            lda  #<${range.first}
+            ldy  #>${range.first}
+            sta  $varname
+            sty  $varname+1
+$loopLabel""")
+        asmgen.translate(stmt.body)
+        asmgen.out("""
+            lda  $varname
+            cmp  #<${range.last}
+            bne  +
+            lda  $varname+1
+            cmp  #>${range.last}
+            bne  +
+            beq  $endLabel
++           lda  $varname
+            bne  +
+            dec  $varname+1
++           dec  $varname
+            jmp  $loopLabel
+$endLabel""")
+        asmgen.loopEndLabels.pop()
+    }
+}

compiler/src/prog8/compiler/target/c64/codegen/FunctionCallAsmGen.kt

@@ -0,0 +1,300 @@
+package prog8.compiler.target.c64.codegen
+
+import prog8.ast.IFunctionCall
+import prog8.ast.Program
+import prog8.ast.base.*
+import prog8.ast.expressions.*
+import prog8.ast.statements.AssignTarget
+import prog8.ast.statements.Subroutine
+import prog8.ast.statements.SubroutineParameter
+import prog8.compiler.AssemblyError
+import prog8.compiler.target.c64.C64MachineDefinition.ESTACK_HI_HEX
+import prog8.compiler.target.c64.C64MachineDefinition.ESTACK_LO_HEX
+import prog8.compiler.toHex
+
+
+internal class FunctionCallAsmGen(private val program: Program, private val asmgen: AsmGen) {
+
+    internal fun translateFunctionCall(stmt: IFunctionCall) {
+        // output the code to setup the parameters and perform the actual call
+        // does NOT output the code to deal with the result values!
+        val sub = stmt.target.targetSubroutine(program.namespace) ?: throw AssemblyError("undefined subroutine ${stmt.target}")
+        val saveX = CpuRegister.X in sub.asmClobbers || sub.regXasResult()
+        if(saveX)
+            asmgen.out("  stx  c64.SCRATCH_ZPREGX")        // we only save X for now (required! is the eval stack pointer), screw A and Y...
+
+        val subName = asmgen.asmIdentifierName(stmt.target)
+        if(stmt.args.isNotEmpty()) {
+            if(sub.asmParameterRegisters.isEmpty()) {
+                // via variables
+                for(arg in sub.parameters.withIndex().zip(stmt.args)) {
+                    argumentViaVariable(sub, arg.first, arg.second)
+                }
+            } else {
+                // via registers
+                if(sub.parameters.size==1) {
+                    // just a single parameter, no risk of clobbering registers
+                    argumentViaRegister(sub, sub.parameters.withIndex().single(), stmt.args[0])
+                } else {
+                    // multiple register arguments, risk of register clobbering.
+                    // evaluate arguments onto the stack, and load the registers from the evaluated values on the stack.
+                    when {
+                        stmt.args.all {it is AddressOf ||
+                                it is NumericLiteralValue ||
+                                it is StringLiteralValue ||
+                                it is ArrayLiteralValue ||
+                                it is IdentifierReference} -> {
+                            // no risk of clobbering for these simple argument types. Optimize the register loading.
+                            for(arg in sub.parameters.withIndex().zip(stmt.args)) {
+                                argumentViaRegister(sub, arg.first, arg.second)
+                            }
+                        }
+                        else -> {
+                            // Risk of clobbering due to complex expression args. Work via the stack.
+                            argsViaStackEvaluation(stmt, sub)
+                        }
+                    }
+                }
+            }
+        }
+        asmgen.out("  jsr  $subName")
+
+        if(saveX)
+            asmgen.out("  ldx  c64.SCRATCH_ZPREGX")        // restore X again
+    }
+
+    private fun argsViaStackEvaluation(stmt: IFunctionCall, sub: Subroutine) {
+        for (arg in stmt.args.reversed())
+            asmgen.translateExpression(arg)
+        for (regparam in sub.asmParameterRegisters) {
+            when (regparam.registerOrPair) {
+                RegisterOrPair.A -> asmgen.out(" inx |  lda  $ESTACK_LO_HEX,x")
+                RegisterOrPair.X -> throw AssemblyError("can't pop into X register - use a variable instead")
+                RegisterOrPair.Y -> asmgen.out(" inx |  ldy  $ESTACK_LO_HEX,x")
+                RegisterOrPair.AX -> throw AssemblyError("can't pop into X register - use a variable instead")
+                RegisterOrPair.AY -> asmgen.out(" inx |  lda  $ESTACK_LO_HEX,x |  ldy  $ESTACK_HI_HEX,x")
+                RegisterOrPair.XY -> throw AssemblyError("can't pop into X register - use a variable instead")
+                null -> {
+                }
+            }
+            when (regparam.statusflag) {
+                Statusflag.Pc -> asmgen.out("""
+                        inx
+                        pha
+                        lda  $ESTACK_LO_HEX,x
+                        beq  +
+                        sec  
+                        bcs  ++
+            +           clc
+            +           pla
+            """)
+                null -> {
+                }
+                else -> throw AssemblyError("can only use Carry as status flag parameter")
+            }
+        }
+    }
+
+    private fun argumentViaVariable(sub: Subroutine, parameter: IndexedValue<SubroutineParameter>, value: Expression) {
+        // pass parameter via a regular variable (not via registers)
+        val valueIDt = value.inferType(program)
+        if(!valueIDt.isKnown)
+            throw AssemblyError("arg type unknown")
+        val valueDt = valueIDt.typeOrElse(DataType.STRUCT)
+        if(!argumentTypeCompatible(valueDt, parameter.value.type))
+            throw AssemblyError("argument type incompatible")
+
+        val paramVar = parameter.value
+        val scopedParamVar = (sub.scopedname+"."+paramVar.name).split(".")
+        val target = AssignTarget(IdentifierReference(scopedParamVar, sub.position), null, null, sub.position)
+        target.linkParents(value.parent)
+        when (value) {
+            is NumericLiteralValue -> {
+                // optimize when the argument is a constant literal
+                when(parameter.value.type) {
+                    in ByteDatatypes -> asmgen.assignFromByteConstant(target, value.number.toShort())
+                    in WordDatatypes -> asmgen.assignFromWordConstant(target, value.number.toInt())
+                    DataType.FLOAT -> asmgen.assignFromFloatConstant(target, value.number.toDouble())
+                    else -> throw AssemblyError("weird parameter datatype")
+                }
+            }
+            is IdentifierReference -> {
+                // optimize when the argument is a variable
+                when (parameter.value.type) {
+                    in ByteDatatypes -> asmgen.assignFromByteVariable(target, value)
+                    in WordDatatypes -> asmgen.assignFromWordVariable(target, value)
+                    DataType.FLOAT -> asmgen.assignFromFloatVariable(target, value)
+                    in PassByReferenceDatatypes -> asmgen.assignFromAddressOf(target, value)
+                    else -> throw AssemblyError("weird parameter datatype")
+                }
+            }
+            is DirectMemoryRead -> {
+                when(value.addressExpression) {
+                    is NumericLiteralValue -> {
+                        val address = (value.addressExpression as NumericLiteralValue).number.toInt()
+                        asmgen.assignFromMemoryByte(target, address, null)
+                    }
+                    is IdentifierReference -> {
+                        asmgen.assignFromMemoryByte(target, null, value.addressExpression as IdentifierReference)
+                    }
+                    else -> {
+                        asmgen.translateExpression(value.addressExpression)
+                        asmgen.out("  jsr  prog8_lib.read_byte_from_address |  inx")
+                        asmgen.assignFromRegister(target, CpuRegister.A)
+                    }
+                }
+            }
+            else -> {
+                asmgen.translateExpression(value)
+                asmgen.assignFromEvalResult(target)
+            }
+        }
+    }
+
+    private fun argumentViaRegister(sub: Subroutine, parameter: IndexedValue<SubroutineParameter>, value: Expression) {
+        // pass argument via a register parameter
+        val valueIDt = value.inferType(program)
+        if(!valueIDt.isKnown)
+            throw AssemblyError("arg type unknown")
+        val valueDt = valueIDt.typeOrElse(DataType.STRUCT)
+        if(!argumentTypeCompatible(valueDt, parameter.value.type))
+            throw AssemblyError("argument type incompatible")
+
+        val paramRegister = sub.asmParameterRegisters[parameter.index]
+        val statusflag = paramRegister.statusflag
+        val register = paramRegister.registerOrPair
+        val stack = paramRegister.stack
+        when {
+            stack -> {
+                // push arg onto the stack
+                // note: argument order is reversed (first argument will be deepest on the stack)
+                asmgen.translateExpression(value)
+            }
+            statusflag!=null -> {
+                if (statusflag == Statusflag.Pc) {
+                    // this param needs to be set last, right before the jsr
+                    // for now, this is already enforced on the subroutine definition by the Ast Checker
+                    when(value) {
+                        is NumericLiteralValue -> {
+                            val carrySet = value.number.toInt() != 0
+                            asmgen.out(if(carrySet) "  sec" else "  clc")
+                        }
+                        is IdentifierReference -> {
+                            val sourceName = asmgen.asmIdentifierName(value)
+                            asmgen.out("""
+            pha
+            lda  $sourceName
+            beq  +
+            sec  
+            bcs  ++
++           clc
++           pla
+""")
+                        }
+                        else -> {
+                            asmgen.translateExpression(value)
+                            asmgen.out("""
+            inx
+            pha
+            lda  $ESTACK_LO_HEX,x
+            beq  +
+            sec  
+            bcs  ++
++           clc
++           pla
+""")
+                        }
+                    }
+                }
+                else throw AssemblyError("can only use Carry as status flag parameter")
+            }
+            register!=null && register.name.length==1 -> {
+                when (value) {
+                    is NumericLiteralValue -> {
+                        asmgen.assignToRegister(CpuRegister.valueOf(register.name), value.number.toShort(), null)
+                    }
+                    is IdentifierReference -> {
+                        asmgen.assignToRegister(CpuRegister.valueOf(register.name), null, value)
+                    }
+                    else -> {
+                        asmgen.translateExpression(value)
+                        when(register) {
+                            RegisterOrPair.A -> asmgen.out("  inx | lda  $ESTACK_LO_HEX,x")
+                            RegisterOrPair.X -> throw AssemblyError("can't pop into X register - use a variable instead")
+                            RegisterOrPair.Y -> asmgen.out("  inx | ldy  $ESTACK_LO_HEX,x")
+                            else -> throw AssemblyError("cannot assign to register pair")
+                        }
+                    }
+                }
+            }
+            register!=null && register.name.length==2 -> {
+                // register pair as a 16-bit value (only possible for subroutine parameters)
+                when (value) {
+                    is NumericLiteralValue -> {
+                        // optimize when the argument is a constant literal
+                        val hex = value.number.toHex()
+                        when (register) {
+                            RegisterOrPair.AX -> asmgen.out("  lda  #<$hex  |  ldx  #>$hex")
+                            RegisterOrPair.AY -> asmgen.out("  lda  #<$hex  |  ldy  #>$hex")
+                            RegisterOrPair.XY -> asmgen.out("  ldx  #<$hex  |  ldy  #>$hex")
+                            else -> {}
+                        }
+                    }
+                    is AddressOf -> {
+                        // optimize when the argument is an address of something
+                        val sourceName = asmgen.asmIdentifierName(value.identifier)
+                        when (register) {
+                            RegisterOrPair.AX -> asmgen.out("  lda  #<$sourceName  |  ldx  #>$sourceName")
+                            RegisterOrPair.AY -> asmgen.out("  lda  #<$sourceName  |  ldy  #>$sourceName")
+                            RegisterOrPair.XY -> asmgen.out("  ldx  #<$sourceName  |  ldy  #>$sourceName")
+                            else -> {}
+                        }
+                    }
+                    is IdentifierReference -> {
+                        val sourceName = asmgen.asmIdentifierName(value)
+                        if(valueDt in PassByReferenceDatatypes) {
+                            when (register) {
+                                RegisterOrPair.AX -> asmgen.out("  lda  #<$sourceName  |  ldx  #>$sourceName")
+                                RegisterOrPair.AY -> asmgen.out("  lda  #<$sourceName  |  ldy  #>$sourceName")
+                                RegisterOrPair.XY -> asmgen.out("  ldx  #<$sourceName  |  ldy  #>$sourceName")
+                                else -> {}
+                            }
+                        } else {
+                            when (register) {
+                                RegisterOrPair.AX -> asmgen.out("  lda  $sourceName  |  ldx  $sourceName+1")
+                                RegisterOrPair.AY -> asmgen.out("  lda  $sourceName  |  ldy  $sourceName+1")
+                                RegisterOrPair.XY -> asmgen.out("  ldx  $sourceName  |  ldy  $sourceName+1")
+                                else -> {}
+                            }
+                        }
+                    }
+                    else -> {
+                        asmgen.translateExpression(value)
+                        if (register == RegisterOrPair.AX || register == RegisterOrPair.XY)
+                            throw AssemblyError("can't use X register here - use a variable")
+                        else if (register == RegisterOrPair.AY)
+                            asmgen.out("  inx |  lda  $ESTACK_LO_HEX,x  |  ldy  $ESTACK_HI_HEX,x")
+                    }
+                }
+            }
+        }
+    }
+
+    private fun argumentTypeCompatible(argType: DataType, paramType: DataType): Boolean {
+        if(argType isAssignableTo paramType)
+            return true
+        if(argType in ByteDatatypes && paramType in ByteDatatypes)
+            return true
+        if(argType in WordDatatypes && paramType in WordDatatypes)
+            return true
+
+        // we have a special rule for some types.
+        // strings are assignable to UWORD, for example, and vice versa
+        if(argType==DataType.STR && paramType==DataType.UWORD)
+            return true
+        if(argType==DataType.UWORD && paramType == DataType.STR)
+            return true
+
+        return false
+    }
+}

compiler/src/prog8/compiler/target/c64/codegen/InplaceAssignmentAsmGen.kt

@@ -0,0 +1,744 @@
+package prog8.compiler.target.c64.codegen
+
+import prog8.ast.Program
+import prog8.ast.base.*
+import prog8.ast.expressions.*
+import prog8.ast.statements.AssignTarget
+import prog8.ast.statements.Assignment
+import prog8.ast.statements.DirectMemoryWrite
+import prog8.ast.statements.VarDecl
+import prog8.compiler.AssemblyError
+import prog8.compiler.target.c64.C64MachineDefinition
+import prog8.compiler.target.c64.C64MachineDefinition.C64Zeropage
+import prog8.compiler.target.c64.C64MachineDefinition.ESTACK_HI_HEX
+import prog8.compiler.target.c64.C64MachineDefinition.ESTACK_LO_HEX
+import prog8.compiler.toHex
+
+
+// OLD inplace-assignment code.
+// should really come up with a more compact way to generate this kind of code...
+
+/***
+
+internal class InplaceAssignmentAsmGen(private val program: Program, private val errors: ErrorReporter, private val asmgen: AsmGen) {
+
+    internal fun translate(assign: Assignment) {
+        if (assign.aug_op == null)
+            translateNormalAssignment(assign)
+        else
+            translateInplaceAssignment(assign)
+    }
+
+    private fun translateInplaceAssignment(assign: Assignment) {
+        require(assign.aug_op != null)
+
+        when {
+            assign.target.identifier != null -> {
+                if (inplaceAssignToIdentifier(assign))
+                    return
+            }
+            assign.target.memoryAddress != null -> {
+                if (inplaceAssignToMemoryByte(assign))
+                    return
+            }
+            assign.target.arrayindexed != null -> {
+                if (inplaceAssignToArrayOrString(assign))
+                    return
+            }
+        }
+
+        // TODO this is the slow FALLBACK, eventually we don't want to have to use it anymore:
+        errors.warn("using suboptimal in-place assignment code (this should still be optimized)", assign.position)
+        val normalAssignment = assign.asDesugaredNonaugmented()
+        return translateNormalAssignment(normalAssignment)
+    }
+
+    private fun inplaceAssignToArrayOrString(assign: Assignment): Boolean {
+        val targetArray = assign.target.arrayindexed!!
+        val arrayName = targetArray.identifier
+        val arrayIndex = targetArray.arrayspec.index
+        val targetName = asmgen.asmIdentifierName(arrayName)
+        val arrayDt = arrayName.targetVarDecl(program.namespace)!!.datatype
+        val constValue = assign.value.constValue(program)?.number
+        if (constValue != null) {
+            // constant value to set in array
+            val hexValue = constValue.toHex()
+            if (assign.aug_op == "setvalue") {
+                when (arrayDt) {
+                    DataType.ARRAY_B, DataType.ARRAY_UB, DataType.STR -> {
+                        if (arrayIndex is NumericLiteralValue)
+                            asmgen.out(" ldy  #${arrayIndex.number.toHex()}")
+                        else
+                            asmgen.translateArrayIndexIntoY(targetArray)
+                        asmgen.out(" lda  #$hexValue |  sta  $targetName,y")
+                    }
+                    DataType.ARRAY_W, DataType.ARRAY_UW -> {
+                        if (arrayIndex is NumericLiteralValue)
+                            asmgen.out(" lda  #${arrayIndex.number.toHex()}")
+                        else
+                            asmgen.translateArrayIndexIntoA(targetArray)
+                        asmgen.out("""
+                            asl  a
+                            tay
+                            lda  #<$hexValue
+                            sta  $targetName,y
+                            lda  #>$hexValue
+                            sta  $targetName+1,y
+                        """)
+                    }
+                    DataType.ARRAY_F -> {
+                        assignFromFloatConstant(assign.target, constValue.toDouble())
+                    }
+                    else -> throw AssemblyError("assignment to array: invalid array dt $arrayDt")
+                }
+            } else {
+                TODO("aug assignment to element in array/string")
+            }
+            return true
+        }
+
+        // non-const value.
+        // !!! DON'T FORGET :  CAN BE AUGMENTED ASSIGNMENT !!!
+        when (assign.value) {
+            is IdentifierReference -> {
+                val sourceName = asmgen.asmIdentifierName(assign.value as IdentifierReference)
+                when(arrayDt) {
+                    DataType.ARRAY_B, DataType.ARRAY_UB, DataType.STR -> {
+                        asmgen.out(" lda  $sourceName")
+                        if (arrayIndex is NumericLiteralValue)
+                            asmgen.out(" ldy  #${arrayIndex.number.toHex()}")
+                        else
+                            asmgen.translateArrayIndexIntoY(targetArray)
+                        asmgen.out(" sta  $targetName,y")
+                    }
+                    DataType.ARRAY_W, DataType.ARRAY_UW -> {
+                        if (arrayIndex is NumericLiteralValue)
+                            asmgen.out(" lda  #${arrayIndex.number.toHex()}")
+                        else
+                            asmgen.translateArrayIndexIntoA(targetArray)
+                        asmgen.out("""
+                            asl  a
+                            tay
+                            lda  $sourceName
+                            sta  $targetName,y
+                            lda  $sourceName+1
+                            sta  $targetName+1,y
+                        """)
+                    }
+                    DataType.ARRAY_F -> return false        // TODO optimize instead of fallback?
+                    else -> throw AssemblyError("assignment to array: invalid array dt $arrayDt")
+                }
+                return true
+            }
+            is AddressOf -> {
+                TODO("assign address into array $assign")
+            }
+            is DirectMemoryRead -> {
+                TODO("assign memory read into array $assign")
+            }
+            is ArrayIndexedExpression -> {
+                if(assign.aug_op != "setvalue")
+                    return false   // we don't put effort into optimizing anything beside simple assignment
+                val valueArrayExpr = assign.value as ArrayIndexedExpression
+                val valueArrayIndex = valueArrayExpr.arrayspec.index
+                val valueVariablename = asmgen.asmIdentifierName(valueArrayExpr.identifier)
+                // val valueDt = valueArrayExpr.identifier.inferType(program).typeOrElse(DataType.STRUCT)
+                when(arrayDt) {
+                    DataType.ARRAY_UB, DataType.ARRAY_B, DataType.STR -> {
+                        if (valueArrayIndex is NumericLiteralValue)
+                            asmgen.out(" ldy  #${valueArrayIndex.number.toHex()}")
+                        else
+                            asmgen.translateArrayIndexIntoY(valueArrayExpr)
+                        asmgen.out(" lda  $valueVariablename,y")
+                        if (arrayIndex is NumericLiteralValue)
+                            asmgen.out(" ldy  #${arrayIndex.number.toHex()}")
+                        else
+                            asmgen.translateArrayIndexIntoY(targetArray)
+                        asmgen.out(" sta  $targetName,y")
+                    }
+                    DataType.ARRAY_UW, DataType.ARRAY_W -> {
+                        if (valueArrayIndex is NumericLiteralValue)
+                            asmgen.out(" ldy  #2*${valueArrayIndex.number.toHex()}")
+                        else {
+                            asmgen.translateArrayIndexIntoA(valueArrayExpr)
+                            asmgen.out(" asl  a |  tay")
+                        }
+                        asmgen.out("""
+                            lda  $valueVariablename,y
+                            pha
+                            lda  $valueVariablename+1,y
+                            pha
+                        """)
+                        if (arrayIndex is NumericLiteralValue)
+                            asmgen.out(" ldy  #2*${arrayIndex.number.toHex()}")
+                        else {
+                            asmgen.translateArrayIndexIntoA(targetArray)
+                            asmgen.out(" asl  a |  tay")
+                        }
+                        asmgen.out("""
+                            pla
+                            sta  $targetName+1,y
+                            pla
+                            sta  $targetName,y
+                        """)
+                        return true
+                    }
+                    DataType.ARRAY_F -> {
+                        if (valueArrayIndex is NumericLiteralValue)
+                            asmgen.out(" ldy  #5*${valueArrayIndex.number.toHex()}")
+                        else {
+                            asmgen.translateArrayIndexIntoA(valueArrayExpr)
+                            asmgen.out("""
+                                sta  ${C64Zeropage.SCRATCH_REG}
+                                asl  a
+                                asl  a
+                                clc
+                                adc  ${C64Zeropage.SCRATCH_REG}
+                                tay
+                            """)
+                        }
+                        asmgen.out("""
+                            lda  $valueVariablename,y
+                            pha
+                            lda  $valueVariablename+1,y
+                            pha
+                            lda  $valueVariablename+2,y
+                            pha
+                            lda  $valueVariablename+3,y
+                            pha
+                            lda  $valueVariablename+4,y
+                            pha
+                        """)
+                        if (arrayIndex is NumericLiteralValue)
+                            asmgen.out(" ldy  #5*${arrayIndex.number.toHex()}")
+                        else {
+                            asmgen.translateArrayIndexIntoA(targetArray)
+                            asmgen.out("""
+                                sta  ${C64Zeropage.SCRATCH_REG}
+                                asl  a
+                                asl  a
+                                clc
+                                adc  ${C64Zeropage.SCRATCH_REG}
+                                tay
+                            """)
+                        }
+                        asmgen.out("""
+                            pla
+                            sta  $targetName+4,y
+                            pla
+                            sta  $targetName+3,y
+                            pla
+                            sta  $targetName+2,y
+                            pla
+                            sta  $targetName+1,y
+                            pla
+                            sta  $targetName,y
+                        """)
+                        return true
+                    }
+                    else -> throw AssemblyError("assignment to array: invalid array dt")
+                }
+                return true
+            }
+            else -> {
+                fallbackAssignment(assign)
+                return true
+            }
+        }
+
+        return false
+    }
+
+    private fun inplaceAssignToMemoryByte(assign: Assignment): Boolean {
+        val address = assign.target.memoryAddress?.addressExpression?.constValue(program)?.number
+                ?: return inplaceAssignToNonConstMemoryByte(assign)
+
+        val hexAddr = address.toHex()
+        val constValue = assign.value.constValue(program)
+        if (constValue != null) {
+            val hexValue = constValue.number.toHex()
+            when (assign.aug_op) {
+                "setvalue" -> asmgen.out(" lda  #$hexValue |  sta  $hexAddr")
+                "+=" -> asmgen.out(" lda  $hexAddr |  clc |  adc  #$hexValue |  sta  $hexAddr")
+                "-=" -> asmgen.out(" lda  $hexAddr |  sec |  sbc  #$hexValue |  sta  $hexAddr")
+                "/=" -> TODO("membyte /= const $hexValue")
+                "*=" -> TODO("membyte *= const $hexValue")
+                "&=" -> asmgen.out(" lda  $hexAddr |  and  #$hexValue |  sta  $hexAddr")
+                "|=" -> asmgen.out(" lda  $hexAddr |  ora  #$hexValue |  sta  $hexAddr")
+                "^=" -> asmgen.out(" lda  $hexAddr |  eor  #$hexValue |  sta  $hexAddr")
+                "%=" -> TODO("membyte %= const $hexValue")
+                "<<=" -> throw AssemblyError("<<= should have been replaced by lsl()")
+                ">>=" -> throw AssemblyError("<<= should have been replaced by lsr()")
+                else -> throw AssemblyError("invalid aug_op ${assign.aug_op}")
+            }
+            return true
+        }
+
+        // non-const value.
+        when (assign.value) {
+            is IdentifierReference -> {
+                val sourceName = asmgen.asmIdentifierName(assign.value as IdentifierReference)
+                when(assign.aug_op) {
+                    "setvalue" -> asmgen.out(" lda  $sourceName |  sta  $hexAddr")
+                    else -> TODO("membyte aug.assign  variable  $assign")
+                }
+                return true
+            }
+            is DirectMemoryRead -> {
+                val memory = (assign.value as DirectMemoryRead).addressExpression.constValue(program)!!.number.toHex()
+                when(assign.aug_op) {
+                    "setvalue" -> asmgen.out(" lda  $memory |  sta  $hexAddr")
+                    else -> TODO("membyte aug.assign  memread  $assign")
+                }
+                return true
+            }
+            is ArrayIndexedExpression -> {
+                TODO("membyte = array value $assign")
+            }
+            is AddressOf -> throw AssemblyError("can't assign address to byte")
+            else -> {
+                fallbackAssignment(assign)
+                return true
+            }
+        }
+
+        return false
+    }
+
+    private fun inplaceAssignToNonConstMemoryByte(assign: Assignment): Boolean {
+        // target address is not constant, so evaluate it from the stack
+        asmgen.translateExpression(assign.target.memoryAddress!!.addressExpression)
+        asmgen.out("""
+            inx
+            lda  $ESTACK_LO_HEX,x
+            sta  ${C64Zeropage.SCRATCH_W1}
+            lda  $ESTACK_HI_HEX,x
+            sta  ${C64Zeropage.SCRATCH_W1}+1
+        """)
+
+        val constValue = assign.value.constValue(program)
+        if (constValue != null) {
+            val hexValue = constValue.number.toHex()
+            asmgen.out("  ldy  #0")
+            when (assign.aug_op) {
+                "setvalue" -> asmgen.out(" lda  #$hexValue |  sta  (${C64Zeropage.SCRATCH_W1}),y")
+                "+=" -> asmgen.out(" lda  (${C64Zeropage.SCRATCH_W1}),y |  clc |  adc  #$hexValue |  sta  (${C64Zeropage.SCRATCH_W1}),y")
+                "-=" -> asmgen.out(" lda  (${C64Zeropage.SCRATCH_W1}),y |  sec |  sbc  #$hexValue |  sta  (${C64Zeropage.SCRATCH_W1}),y")
+                "/=" -> TODO("membyte /= const $hexValue")
+                "*=" -> TODO("membyte *= const $hexValue")
+                "&=" -> asmgen.out(" lda  (${C64Zeropage.SCRATCH_W1}),y |  and  #$hexValue |  sta  (${C64Zeropage.SCRATCH_W1}),y")
+                "|=" -> asmgen.out(" lda  (${C64Zeropage.SCRATCH_W1}),y |  ora  #$hexValue |  sta  (${C64Zeropage.SCRATCH_W1}),y")
+                "^=" -> asmgen.out(" lda  (${C64Zeropage.SCRATCH_W1}),y |  eor  #$hexValue |  sta  (${C64Zeropage.SCRATCH_W1}),y")
+                "%=" -> TODO("membyte %= const $hexValue")
+                "<<=" -> throw AssemblyError("<<= should have been replaced by lsl()")
+                ">>=" -> throw AssemblyError("<<= should have been replaced by lsr()")
+                else -> throw AssemblyError("invalid aug_op ${assign.aug_op}")
+            }
+            return true
+        }
+
+        // non-const value.
+        // !!! DON'T FORGET :  CAN BE AUGMENTED ASSIGNMENT !!!
+        when (assign.value) {
+            is IdentifierReference -> {
+                val sourceName = asmgen.asmIdentifierName(assign.value as IdentifierReference)
+                TODO("membyte = variable $assign")
+            }
+            is DirectMemoryRead -> {
+                TODO("membyte = memread $assign")
+            }
+            is ArrayIndexedExpression -> {
+                if (assign.aug_op == "setvalue") {
+                    val arrayExpr = assign.value as ArrayIndexedExpression
+                    val arrayIndex = arrayExpr.arrayspec.index
+                    val variablename = asmgen.asmIdentifierName(arrayExpr.identifier)
+                    val arrayDt = arrayExpr.identifier.inferType(program).typeOrElse(DataType.STRUCT)
+                    if (arrayDt != DataType.ARRAY_B && arrayDt != DataType.ARRAY_UB && arrayDt != DataType.STR)
+                        throw AssemblyError("assign to memory byte: expected byte array or string source")
+                    if (arrayIndex is NumericLiteralValue)
+                        asmgen.out(" ldy  #${arrayIndex.number.toHex()}")
+                    else
+                        asmgen.translateArrayIndexIntoY(arrayExpr)
+                    asmgen.out("""
+                        lda  $variablename,y
+                        ldy  #0
+                        sta  (${C64Zeropage.SCRATCH_W1}),y
+                    """)
+                } else {
+                    // TODO optimize more augmented assignment cases
+                    val normalAssign = assign.asDesugaredNonaugmented()
+                    asmgen.translateExpression(normalAssign.value)
+                    assignFromEvalResult(normalAssign.target)
+                }
+                return true
+            }
+            is AddressOf -> throw AssemblyError("can't assign memory address to memory byte")
+            else -> {
+                fallbackAssignment(assign)
+                return true
+            }
+        }
+
+        return false   // TODO optimized
+    }
+
+    private fun inplaceAssignToIdentifier(assign: Assignment): Boolean {
+        val targetType = assign.target.inferType(program, assign)
+        val constNumber = assign.value.constValue(program)?.number
+        val targetName = asmgen.asmIdentifierName(assign.target.identifier!!)
+
+        when (targetType.typeOrElse(DataType.STRUCT)) {
+            DataType.UBYTE, DataType.BYTE -> {
+                // (u)byte assignment
+                if (constNumber != null) {
+                    val hexValue = constNumber.toHex()
+                    when (assign.aug_op) {
+                        "setvalue" -> asmgen.out(" lda  #$hexValue |  sta  $targetName")
+                        "+=" -> asmgen.out(" lda  $targetName |  clc |  adc  #$hexValue |  sta  $targetName")
+                        "-=" -> asmgen.out(" lda  $targetName |  sec |  sbc  #$hexValue |  sta  $targetName")
+                        "/=" -> TODO("variable /= const $hexValue")
+                        "*=" -> TODO("variable *= const $hexValue")
+                        "&=" -> asmgen.out(" lda  $targetName |  and  #$hexValue |  sta  $targetName")
+                        "|=" -> asmgen.out(" lda  $targetName |  ora  #$hexValue |  sta  $targetName")
+                        "^=" -> asmgen.out(" lda  $targetName |  eor  #$hexValue |  sta  $targetName")
+                        "%=" -> TODO("variable %= const $hexValue")
+                        "<<=" -> throw AssemblyError("<<= should have been replaced by lsl()")
+                        ">>=" -> throw AssemblyError("<<= should have been replaced by lsr()")
+                        else -> throw AssemblyError("invalid aug_op ${assign.aug_op}")
+                    }
+                    return true
+                }
+
+                // non-const (u)byte value
+                // !!! DON'T FORGET :  CAN BE AUGMENTED ASSIGNMENT !!!
+                when (assign.value) {
+                    is IdentifierReference -> {
+                        val sourceName = asmgen.asmIdentifierName(assign.value as IdentifierReference)
+                        when (assign.aug_op) {
+                            "setvalue" -> asmgen.out(" lda  $sourceName |  sta  $targetName")
+                            "+=" -> asmgen.out(" lda  $targetName |  clc |  adc  $sourceName |  sta  $targetName")
+                            "-=" -> asmgen.out(" lda  $targetName |  sec |  sbc  $sourceName |  sta  $targetName")
+                            "/=" -> TODO("variable /= variable")
+                            "*=" -> TODO("variable *= variable")
+                            "&=" -> asmgen.out(" lda  $targetName |  and  $sourceName |  sta  $targetName")
+                            "|=" -> asmgen.out(" lda  $targetName |  ora  $sourceName |  sta  $targetName")
+                            "^=" -> asmgen.out(" lda  $targetName |  eor  $sourceName |  sta  $targetName")
+                            "%=" -> TODO("variable %= variable")
+                            "<<=" -> throw AssemblyError("<<= should have been replaced by lsl()")
+                            ">>=" -> throw AssemblyError("<<= should have been replaced by lsr()")
+                            else -> throw AssemblyError("invalid aug_op ${assign.aug_op}")
+                        }
+                        return true
+                    }
+                    is DirectMemoryRead -> {
+                        TODO("variable = memory read $assign")
+                    }
+                    is ArrayIndexedExpression -> {
+                        if (assign.aug_op == "setvalue") {
+                            val arrayExpr = assign.value as ArrayIndexedExpression
+                            val arrayIndex = arrayExpr.arrayspec.index
+                            val variablename = asmgen.asmIdentifierName(arrayExpr.identifier)
+                            val arrayDt = arrayExpr.identifier.inferType(program).typeOrElse(DataType.STRUCT)
+                            if (arrayDt != DataType.ARRAY_B && arrayDt != DataType.ARRAY_UB && arrayDt != DataType.STR)
+                                throw AssemblyError("assign to identifier: expected byte array or string source")
+                            if (arrayIndex is NumericLiteralValue)
+                                asmgen.out(" ldy  #${arrayIndex.number.toHex()}")
+                            else
+                                asmgen.translateArrayIndexIntoY(arrayExpr)
+                            asmgen.out(" lda  $variablename,y |  sta  $targetName")
+                        } else {
+                            // TODO optimize more augmented assignment cases
+                            val normalAssign = assign.asDesugaredNonaugmented()
+                            asmgen.translateExpression(normalAssign.value)
+                            assignFromEvalResult(normalAssign.target)
+                        }
+                        return true
+                    }
+                    else -> {
+                        fallbackAssignment(assign)
+                        return true
+                    }
+                }
+            }
+            DataType.UWORD, DataType.WORD -> {
+                if (constNumber != null) {
+                    val hexNumber = constNumber.toHex()
+                    when (assign.aug_op) {
+                        "setvalue" -> {
+                            asmgen.out("""
+                                lda  #<$hexNumber
+                                sta  $targetName
+                                lda  #>$hexNumber
+                                sta  $targetName+1
+                            """)
+                        }
+                        "+=" -> {
+                            asmgen.out("""
+                                lda  $targetName
+                                clc
+                                adc  #<$hexNumber
+                                sta  $targetName
+                                lda  $targetName+1
+                                adc  #>$hexNumber
+                                sta  $targetName+1
+                            """)
+                        }
+                        "-=" -> {
+                            asmgen.out("""
+                                lda  $targetName
+                                sec
+                                sbc  #<$hexNumber
+                                sta  $targetName
+                                lda  $targetName+1
+                                sbc  #>$hexNumber
+                                sta  $targetName+1
+                            """)
+                        }
+                        else -> TODO("variable aug.assign ${assign.aug_op} const $hexNumber")
+                    }
+                    return true
+                }
+
+                // non-const value
+                // !!! DON'T FORGET :  CAN BE AUGMENTED ASSIGNMENT !!!
+                when (assign.value) {
+                    is IdentifierReference -> {
+                        val sourceName = asmgen.asmIdentifierName(assign.value as IdentifierReference)
+                        when (assign.aug_op) {
+                            "setvalue" -> {
+                                asmgen.out("""
+                                    lda  $sourceName
+                                    sta  $targetName
+                                    lda  $sourceName+1
+                                    sta  $targetName+1
+                                """)
+                            }
+                            "+=" -> {
+                                asmgen.out("""
+                                    lda  $targetName
+                                    clc
+                                    adc  $sourceName
+                                    sta  $targetName
+                                    lda  $targetName+1
+                                    adc  $sourceName+1
+                                    sta  $targetName+1
+                                """)
+                                return true
+                            }
+                            "-=" -> {
+                                asmgen.out("""
+                                    lda  $targetName
+                                    sec
+                                    sbc  $sourceName
+                                    sta  $targetName
+                                    lda  $targetName+1
+                                    sbc  $sourceName+1
+                                    sta  $targetName+1
+                                """)
+                                return true
+                            }
+                            else -> {
+                                TODO("variable aug.assign variable")
+                            }
+                        }
+                        return true
+                    }
+                    is DirectMemoryRead -> throw AssemblyError("expected a typecast for assigning memory read byte to word")
+                    is AddressOf -> {
+                        val name = asmgen.asmIdentifierName((assign.value as AddressOf).identifier)
+                        asmgen.out(" lda  #<$name |  sta  $targetName |  lda  #>$name |  sta  $targetName+1")
+                        return true
+                    }
+                    is ArrayIndexedExpression -> {
+                        if (assign.aug_op == "setvalue") {
+                            val arrayExpr = assign.value as ArrayIndexedExpression
+                            val arrayIndex = arrayExpr.arrayspec.index
+                            val variablename = asmgen.asmIdentifierName(arrayExpr.identifier)
+                            val arrayDt = arrayExpr.identifier.inferType(program).typeOrElse(DataType.STRUCT)
+                            if (arrayDt != DataType.ARRAY_W && arrayDt != DataType.ARRAY_UW)
+                                throw AssemblyError("assign to identifier: expected word array source")
+                            if (arrayIndex is NumericLiteralValue)
+                                asmgen.out(" lda  #${arrayIndex.number.toHex()}")
+                            else
+                                asmgen.translateArrayIndexIntoA(arrayExpr)
+                            asmgen.out("""
+                                asl  a
+                                tay
+                                lda  $variablename,y
+                                sta  $targetName
+                                lda  $variablename+1,y
+                                sta  $targetName+1
+                            """)
+                        } else {
+                            // TODO optimize more augmented assignment cases
+                            val normalAssign = assign.asDesugaredNonaugmented()
+                            asmgen.translateExpression(normalAssign.value)
+                            assignFromEvalResult(normalAssign.target)
+                        }
+                        return true
+                    }
+                    else -> {
+                        fallbackAssignment(assign)
+                        return true
+                    }
+                }
+            }
+            DataType.FLOAT -> {
+                if (constNumber != null) {
+                    // assign a constant
+                    val floatConst = asmgen.getFloatConst(constNumber.toDouble())
+                    when (assign.aug_op) {
+                        "setvalue" -> assignFromFloatConstant(assign.target, constNumber.toDouble())
+                        "+=" -> {
+                            if (constNumber == 0.5) {
+                                asmgen.out("""
+                                lda  #<$targetName
+                                ldy  #>$targetName
+                                jsr  c64flt.MOVFM
+                                jsr  c64flt.FADDH
+                                stx  c64.SCRATCH_ZPREGX
+                                ldx  #<$targetName
+                                ldy  #>$targetName
+                                jsr  c64flt.MOVMF
+                                ldx  c64.SCRATCH_ZPREGX
+                            """)
+                            } else {
+                                asmgen.out("""
+                                lda  #<$targetName
+                                ldy  #>$targetName
+                                jsr  c64flt.MOVFM
+                                lda  #<$floatConst
+                                ldy  #>$floatConst
+                                jsr  c64flt.FADD
+                                stx  c64.SCRATCH_ZPREGX
+                                ldx  #<$targetName
+                                ldy  #>$targetName
+                                jsr  c64flt.MOVMF
+                                ldx  c64.SCRATCH_ZPREGX
+                            """)
+                            }
+                            return true
+                        }
+                        "-=" -> {
+                            asmgen.out("""
+                            lda  #<$floatConst
+                            ldy  #>$floatConst
+                            jsr  c64flt.MOVFM
+                            lda  #<$targetName
+                            ldy  #>$targetName
+                            jsr  c64flt.FSUB
+                            stx  c64.SCRATCH_ZPREGX
+                            ldx  #<$targetName
+                            ldy  #>$targetName
+                            jsr  c64flt.MOVMF
+                            ldx  c64.SCRATCH_ZPREGX
+                        """)
+                            return true
+                        }
+                        else -> TODO("float const value aug.assign $assign")
+                    }
+                    return true
+                }
+
+                // non-const float value.
+                // !!! DON'T FORGET :  CAN BE AUGMENTED ASSIGNMENT !!!
+                when (assign.value) {
+                    is IdentifierReference -> {
+                        when (assign.aug_op) {
+                            "setvalue" -> assignFromFloatVariable(assign.target, assign.value as IdentifierReference)
+                            "+=" -> return false        // TODO optimized float += variable
+                            "-=" -> return false        // TODO optimized float -= variable
+                            else -> TODO("float non-const value aug.assign $assign")
+                        }
+                        return true
+                    }
+                    is ArrayIndexedExpression -> {
+                        when(assign.aug_op) {
+                            "setvalue" -> {
+                                val arrayExpr = assign.value as ArrayIndexedExpression
+                                val arrayIndex = arrayExpr.arrayspec.index
+                                val variablename = asmgen.asmIdentifierName(arrayExpr.identifier)
+                                val arrayDt = arrayExpr.identifier.inferType(program).typeOrElse(DataType.STRUCT)
+                                if (arrayDt != DataType.ARRAY_F)
+                                    throw AssemblyError("assign to identifier: expected float array source")
+                                if (arrayIndex is NumericLiteralValue)
+                                    asmgen.out(" lda  #${arrayIndex.number.toHex()}")
+                                else
+                                    asmgen.translateArrayIndexIntoA(arrayExpr)
+                                asmgen.out("""
+                                    sta  c64.SCRATCH_ZPB1
+                                    asl  a
+                                    asl  a
+                                    clc
+                                    adc  c64.SCRATCH_ZPB1
+                                    tay
+                                    lda  $variablename,y
+                                    sta  $targetName
+                                    lda  $variablename+1,y
+                                    sta  $targetName+1
+                                    lda  $variablename+2,y
+                                    sta  $targetName+2
+                                    lda  $variablename+3,y
+                                    sta  $targetName+3
+                                    lda  $variablename+4,y
+                                    sta  $targetName+4
+                                """)
+                            }
+                            else -> TODO("float $assign")
+                        }
+                        return true
+                    }
+                    else -> {
+                        fallbackAssignment(assign)
+                        return true
+                    }
+                }
+            }
+            DataType.STR -> {
+                val identifier = assign.value as? IdentifierReference
+                        ?: throw AssemblyError("string value assignment expects identifier value")
+                val sourceName = asmgen.asmIdentifierName(identifier)
+                asmgen.out("""
+                    lda  #<$targetName
+                    sta  ${C64Zeropage.SCRATCH_W1}
+                    lda  #>$targetName
+                    sta  ${C64Zeropage.SCRATCH_W1+1}
+                    lda  #<$sourceName
+                    ldy  #>$sourceName
+                    jsr  prog8_lib.strcpy
+                """)
+                return true
+            }
+            else -> throw AssemblyError("assignment to identifier: invalid target datatype: $targetType")
+        }
+        return false
+    }
+
+    private fun fallbackAssignment(assign: Assignment) {
+        if (assign.aug_op != "setvalue") {
+            /* stack-based evaluation of the expression is required */
+            val normalAssign = assign.asDesugaredNonaugmented()
+            asmgen.translateExpression(normalAssign.value)
+            assignFromEvalResult(normalAssign.target)
+        } else {
+            when (assign.value) {
+                is FunctionCall -> {
+                    // TODO is there a way to avoid function return value being passed via the stack?
+                    //      for instance, 1 byte return value always in A, etc
+                    val normalAssign = assign.asDesugaredNonaugmented()
+                    asmgen.translateExpression(normalAssign.value)
+                    assignFromEvalResult(normalAssign.target)
+                }
+                else -> {
+                    /* stack-based evaluation of the expression is required */
+                    val normalAssign = assign.asDesugaredNonaugmented()
+                    asmgen.translateExpression(normalAssign.value)
+                    assignFromEvalResult(normalAssign.target)
+                }
+            }
+        }
+    }
+}
+
+
+***/

compiler/src/prog8/compiler/target/c64/codegen/PostIncrDecrAsmGen.kt

@@ -0,0 +1,128 @@
+package prog8.compiler.target.c64.codegen
+
+import prog8.ast.Program
+import prog8.ast.base.*
+import prog8.ast.expressions.IdentifierReference
+import prog8.ast.expressions.NumericLiteralValue
+import prog8.ast.statements.PostIncrDecr
+import prog8.compiler.AssemblyError
+import prog8.compiler.target.c64.C64MachineDefinition.C64Zeropage
+import prog8.compiler.toHex
+
+
+internal class PostIncrDecrAsmGen(private val program: Program, private val asmgen: AsmGen) {
+    internal fun translate(stmt: PostIncrDecr) {
+        val incr = stmt.operator=="++"
+        val targetIdent = stmt.target.identifier
+        val targetMemory = stmt.target.memoryAddress
+        val targetArrayIdx = stmt.target.arrayindexed
+        when {
+            targetIdent!=null -> {
+                val what = asmgen.asmIdentifierName(targetIdent)
+                when (stmt.target.inferType(program, stmt).typeOrElse(DataType.STRUCT)) {
+                    in ByteDatatypes -> asmgen.out(if (incr) "  inc  $what" else "  dec  $what")
+                    in WordDatatypes -> {
+                        if(incr)
+                            asmgen.out(" inc  $what |  bne  + |  inc  $what+1 |+")
+                        else
+                            asmgen.out("""
+        lda  $what
+        bne  +
+        dec  $what+1
++       dec  $what 
+""")
+                    }
+                    DataType.FLOAT -> {
+                        asmgen.out("  lda  #<$what |  ldy  #>$what")
+                        asmgen.out(if(incr) "  jsr  c64flt.inc_var_f" else "  jsr  c64flt.dec_var_f")
+                    }
+                    else -> throw AssemblyError("need numeric type")
+                }
+            }
+            targetMemory!=null -> {
+                when (val addressExpr = targetMemory.addressExpression) {
+                    is NumericLiteralValue -> {
+                        val what = addressExpr.number.toHex()
+                        asmgen.out(if(incr) "  inc  $what" else "  dec  $what")
+                    }
+                    is IdentifierReference -> {
+                        val what = asmgen.asmIdentifierName(addressExpr)
+                        asmgen.out("  lda  $what |  sta  (+) +1 |  lda  $what+1 |  sta  (+) +2")
+                        if(incr)
+                            asmgen.out("+\tinc  ${'$'}ffff\t; modified")
+                        else
+                            asmgen.out("+\tdec  ${'$'}ffff\t; modified")
+                    }
+                    else -> throw AssemblyError("weird target type $targetMemory")
+                }
+            }
+            targetArrayIdx!=null -> {
+                val index = targetArrayIdx.arrayspec.index
+                val what = asmgen.asmIdentifierName(targetArrayIdx.identifier)
+                val arrayDt = targetArrayIdx.identifier.inferType(program).typeOrElse(DataType.STRUCT)
+                val elementDt = ArrayElementTypes.getValue(arrayDt)
+                when(index) {
+                    is NumericLiteralValue -> {
+                        val indexValue = index.number.toInt() * elementDt.memorySize()
+                        when(elementDt) {
+                            in ByteDatatypes -> asmgen.out(if (incr) "  inc  $what+$indexValue" else "  dec  $what+$indexValue")
+                            in WordDatatypes -> {
+                                if(incr)
+                                    asmgen.out(" inc  $what+$indexValue |  bne  + |  inc  $what+$indexValue+1 |+")
+                                else
+                                    asmgen.out("""
+        lda  $what+$indexValue
+        bne  +
+        dec  $what+$indexValue+1
++       dec  $what+$indexValue 
+""")
+                            }
+                            DataType.FLOAT -> {
+                                asmgen.out("  lda  #<$what+$indexValue |  ldy  #>$what+$indexValue")
+                                asmgen.out(if(incr) "  jsr  c64flt.inc_var_f" else "  jsr  c64flt.dec_var_f")
+                            }
+                            else -> throw AssemblyError("need numeric type")
+                        }
+                    }
+                    is IdentifierReference -> {
+                        asmgen.translateArrayIndexIntoA(targetArrayIdx)
+                        incrDecrArrayvalueWithIndexA(incr, arrayDt, what)
+                    }
+                    else -> {
+                        asmgen.translateArrayIndexIntoA(targetArrayIdx)
+                        incrDecrArrayvalueWithIndexA(incr, arrayDt, what)
+                    }
+                }
+            }
+            else -> throw AssemblyError("weird target type ${stmt.target}")
+        }
+    }
+
+    private fun incrDecrArrayvalueWithIndexA(incr: Boolean, arrayDt: DataType, arrayVarName: String) {
+        asmgen.out("  stx  ${C64Zeropage.SCRATCH_REG_X} |  tax")
+        when(arrayDt) {
+            DataType.STR,
+            DataType.ARRAY_UB, DataType.ARRAY_B -> {
+                asmgen.out(if(incr) "  inc  $arrayVarName,x" else "  dec  $arrayVarName,x")
+            }
+            DataType.ARRAY_UW, DataType.ARRAY_W -> {
+                if(incr)
+                    asmgen.out(" inc  $arrayVarName,x |  bne  + |  inc  $arrayVarName+1,x |+")
+                else
+                    asmgen.out("""
+        lda  $arrayVarName,x
+        bne  +
+        dec  $arrayVarName+1,x
++       dec  $arrayVarName 
+""")
+            }
+            DataType.ARRAY_F -> {
+                asmgen.out("  lda  #<$arrayVarName |  ldy  #>$arrayVarName")
+                asmgen.out(if(incr) "  jsr  c64flt.inc_indexed_var_f" else "  jsr  c64flt.dec_indexed_var_f")
+            }
+            else -> throw AssemblyError("weird array dt")
+        }
+        asmgen.out("  ldx  ${C64Zeropage.SCRATCH_REG_X}")
+    }
+
+}

compiler/src/prog8/compiler/target/c64/codegen2/AnonymousScopeVarsCleanup.kt

@@ -1,48 +0,0 @@
-package prog8.compiler.target.c64.codegen2
-
-import prog8.ast.Program
-import prog8.ast.base.AstException
-import prog8.ast.base.NameError
-import prog8.ast.processing.IAstModifyingVisitor
-import prog8.ast.statements.AnonymousScope
-import prog8.ast.statements.Statement
-import prog8.ast.statements.VarDecl
-
-class AnonymousScopeVarsCleanup(val program: Program): IAstModifyingVisitor {
-    private val checkResult: MutableList<AstException> = mutableListOf()
-    private val varsToMove: MutableMap<AnonymousScope, List<VarDecl>> = mutableMapOf()
-
-    fun result(): List<AstException> {
-        return checkResult
-    }
-
-    override fun visit(program: Program) {
-        varsToMove.clear()
-        super.visit(program)
-        for((scope, decls) in varsToMove) {
-            val sub = scope.definingSubroutine()!!
-            val existingVariables = sub.statements.filterIsInstance<VarDecl>().associate { it.name to it }
-            var conflicts = false
-            decls.forEach {
-                val existing = existingVariables[it.name]
-                if (existing!=null) {
-                    checkResult.add(NameError("variable ${it.name} already defined in subroutine ${sub.name} at ${existing.position}", it.position))
-                    conflicts = true
-                }
-            }
-            if (!conflicts) {
-                decls.forEach { scope.remove(it) }
-                sub.statements.addAll(0, decls)
-                decls.forEach { it.parent = sub }
-            }
-        }
-    }
-
-    override fun visit(scope: AnonymousScope): Statement {
-        val scope2 = super.visit(scope) as AnonymousScope
-        val vardecls = scope2.statements.filterIsInstance<VarDecl>()
-        varsToMove[scope2] = vardecls
-        return scope2
-    }
-}
-

compiler/src/prog8/compiler/target/c64/codegen2/BuiltinFunctionsAsmGen.kt

@@ -1,252 +0,0 @@
-package prog8.compiler.target.c64.codegen2
-
-import prog8.ast.IFunctionCall
-import prog8.ast.Program
-import prog8.ast.base.ByteDatatypes
-import prog8.ast.base.DataType
-import prog8.ast.base.Register
-import prog8.ast.base.WordDatatypes
-import prog8.ast.expressions.*
-import prog8.ast.statements.AssignTarget
-import prog8.ast.statements.FunctionCallStatement
-import prog8.compiler.CompilationOptions
-import prog8.compiler.Zeropage
-import prog8.compiler.target.c64.MachineDefinition.ESTACK_HI_PLUS1_HEX
-import prog8.compiler.target.c64.MachineDefinition.ESTACK_LO_HEX
-import prog8.compiler.target.c64.MachineDefinition.ESTACK_LO_PLUS1_HEX
-import prog8.compiler.toHex
-import prog8.functions.FunctionSignature
-
-internal class BuiltinFunctionsAsmGen(private val program: Program,
-                                      private val options: CompilationOptions,
-                                      private val zeropage: Zeropage,
-                                      private val asmgen: AsmGen2) {
-
-    internal fun translateFunctioncallExpression(fcall: FunctionCall, func: FunctionSignature) {
-        translateFunctioncall(fcall, func, false)
-    }
-
-    internal fun translateFunctioncallStatement(fcall: FunctionCallStatement, func: FunctionSignature) {
-        translateFunctioncall(fcall, func, true)
-    }
-
-    private fun translateFunctioncall(fcall: IFunctionCall, func: FunctionSignature, discardResult: Boolean) {
-        val functionName = fcall.target.nameInSource.last()
-        if(discardResult) {
-            if(func.pure)
-                return  // can just ignore the whole function call altogether
-            else if(func.returntype!=null)
-                throw AssemblyError("discarding result of non-pure function $fcall")
-        }
-
-        when(functionName) {
-            "msb" -> {
-                val arg = fcall.arglist.single()
-                if(arg.inferType(program) !in WordDatatypes)
-                    throw AssemblyError("msb required word argument")
-                if(arg is NumericLiteralValue)
-                    throw AssemblyError("should have been const-folded")
-                if(arg is IdentifierReference) {
-                    val sourceName = asmgen.asmIdentifierName(arg)
-                    asmgen.out("  lda  $sourceName+1 |  sta  $ESTACK_LO_HEX,x |  dex")
-                } else {
-                    asmgen.translateExpression(arg)
-                    asmgen.out("  lda  $ESTACK_HI_PLUS1_HEX,x |  sta  $ESTACK_LO_PLUS1_HEX,x")
-                }
-            }
-            "mkword" -> {
-                translateFunctionArguments(fcall.arglist, func)
-                asmgen.out("  inx | lda  $ESTACK_LO_HEX,x  | sta  $ESTACK_HI_PLUS1_HEX,x")
-            }
-            "abs" -> {
-                translateFunctionArguments(fcall.arglist, func)
-                val dt = fcall.arglist.single().inferType(program)!!
-                when (dt) {
-                    in ByteDatatypes -> asmgen.out("  jsr  prog8_lib.abs_b")
-                    in WordDatatypes -> asmgen.out("  jsr  prog8_lib.abs_w")
-                    DataType.FLOAT -> asmgen.out("  jsr  c64flt.abs_f")
-                    else -> throw AssemblyError("weird type")
-                }
-            }
-            "swap" -> {
-                val first = fcall.arglist[0]
-                val second = fcall.arglist[1]
-                asmgen.translateExpression(first)
-                asmgen.translateExpression(second)
-                // pop in reverse order
-                val firstTarget = AssignTarget.fromExpr(first)
-                val secondTarget = AssignTarget.fromExpr(second)
-                asmgen.assignFromEvalResult(firstTarget)
-                asmgen.assignFromEvalResult(secondTarget)
-            }
-            // TODO: any(f), all(f), max(f), min(f), sum(f)
-            "sin", "cos", "tan", "atan",
-            "ln", "log2", "sqrt", "rad",
-            "deg", "round", "floor", "ceil",
-            "rdnf" -> {
-                translateFunctionArguments(fcall.arglist, func)
-                asmgen.out("  jsr  c64flt.func_$functionName")
-            }
-/*
-        TODO this was the old code for bit rotations:
-            Opcode.SHL_BYTE -> AsmFragment(" asl  $variable+$index", 8)
-            Opcode.SHR_UBYTE -> AsmFragment(" lsr  $variable+$index", 8)
-            Opcode.SHR_SBYTE -> AsmFragment(" lda  $variable+$index |  asl  a |  ror  $variable+$index")
-            Opcode.SHL_WORD -> AsmFragment(" asl  $variable+${index * 2 + 1} |  rol  $variable+${index * 2}", 8)
-            Opcode.SHR_UWORD -> AsmFragment(" lsr  $variable+${index * 2 + 1} |  ror  $variable+${index * 2}", 8)
-            Opcode.SHR_SWORD -> AsmFragment(" lda  $variable+${index * 2 + 1} |  asl  a |  ror  $variable+${index * 2 + 1} |  ror  $variable+${index * 2}", 8)
-            Opcode.ROL_BYTE -> AsmFragment(" rol  $variable+$index", 8)
-            Opcode.ROR_BYTE -> AsmFragment(" ror  $variable+$index", 8)
-            Opcode.ROL_WORD -> AsmFragment(" rol  $variable+${index * 2 + 1} |  rol  $variable+${index * 2}", 8)
-            Opcode.ROR_WORD -> AsmFragment(" ror  $variable+${index * 2 + 1} |  ror  $variable+${index * 2}", 8)
-            Opcode.ROL2_BYTE -> AsmFragment(" lda  $variable+$index |  cmp  #\$80 |  rol  $variable+$index", 8)
-            Opcode.ROR2_BYTE -> AsmFragment(" lda  $variable+$index |  lsr  a |  bcc  + |  ora  #\$80 |+ |  sta  $variable+$index", 10)
-            Opcode.ROL2_WORD -> AsmFragment(" asl  $variable+${index * 2 + 1} |  rol  $variable+${index * 2} |  bcc  + |  inc  $variable+${index * 2 + 1} |+", 20)
-            Opcode.ROR2_WORD -> AsmFragment(" lsr  $variable+${index * 2 + 1} |  ror  $variable+${index * 2} |  bcc  + |  lda  $variable+${index * 2 + 1} |  ora  #\$80 |  sta  $variable+${index * 2 + 1} |+", 30)
-
- */
-            "lsl" -> {
-                // in-place
-                val what = fcall.arglist.single()
-                val dt = what.inferType(program)!!
-                when(dt) {
-                    in ByteDatatypes -> {
-                        when(what) {
-                            is RegisterExpr -> {
-                                when(what.register) {
-                                    Register.A -> asmgen.out("  asl  a")
-                                    Register.X -> asmgen.out("  txa  |  asl  a |  tax")
-                                    Register.Y -> asmgen.out("  tya  |  asl  a |  tay")
-                                }
-                            }
-                            is IdentifierReference -> asmgen.out("  asl  ${asmgen.asmIdentifierName(what)}")
-                            is DirectMemoryRead -> {
-                                if(what.addressExpression is NumericLiteralValue) {
-                                    asmgen.out("  asl  ${(what.addressExpression as NumericLiteralValue).number.toHex()}")
-                                } else {
-                                    TODO("lsl memory byte $what")
-                                }
-                            }
-                            is ArrayIndexedExpression -> {
-                                TODO("lsl byte array $what")
-                            }
-                            else -> throw AssemblyError("weird type")
-                        }
-                    }
-                    in WordDatatypes -> {
-                        TODO("lsl word $what")
-                    }
-                    else -> throw AssemblyError("weird type")
-                }
-            }
-            "lsr" -> {
-                // in-place
-                val what = fcall.arglist.single()
-                val dt = what.inferType(program)!!
-                when(dt) {
-                    DataType.UBYTE -> {
-                        when(what) {
-                            is RegisterExpr -> {
-                                when(what.register) {
-                                    Register.A -> asmgen.out("  lsr  a")
-                                    Register.X -> asmgen.out("  txa  |  lsr  a |  tax")
-                                    Register.Y -> asmgen.out("  tya  |  lsr  a |  tay")
-                                }
-                            }
-                            is IdentifierReference -> asmgen.out("  lsr  ${asmgen.asmIdentifierName(what)}")
-                            is DirectMemoryRead -> {
-                                if(what.addressExpression is NumericLiteralValue) {
-                                    asmgen.out("  lsr  ${(what.addressExpression as NumericLiteralValue).number.toHex()}")
-                                } else {
-                                    TODO("lsr memory byte $what")
-                                }
-                            }
-                            is ArrayIndexedExpression -> {
-                                TODO("lsr byte array $what")
-                            }
-                            else -> throw AssemblyError("weird type")
-                        }
-                    }
-                    DataType.BYTE -> {
-                        TODO("lsr sbyte $what")
-                    }
-                    DataType.UWORD -> {
-                        TODO("lsr sword $what")
-                    }
-                    DataType.WORD -> {
-                        TODO("lsr word $what")
-                    }
-                    else -> throw AssemblyError("weird type")
-                }
-            }
-            "rol" -> {
-                // in-place
-                val what = fcall.arglist.single()
-                val dt = what.inferType(program)!!
-                when(dt) {
-                    DataType.UBYTE -> {
-                        TODO("rol ubyte")
-                    }
-                    DataType.UWORD -> {
-                        TODO("rol uword")
-                    }
-                    else -> throw AssemblyError("weird type")
-                }
-            }
-            "rol2" -> {
-                // in-place
-                val what = fcall.arglist.single()
-                val dt = what.inferType(program)!!
-                when(dt) {
-                    DataType.UBYTE -> {
-                        TODO("rol2 ubyte")
-                    }
-                    DataType.UWORD -> {
-                        TODO("rol2 uword")
-                    }
-                    else -> throw AssemblyError("weird type")
-                }
-            }
-            "ror" -> {
-                // in-place
-                val what = fcall.arglist.single()
-                val dt = what.inferType(program)!!
-                when(dt) {
-                    DataType.UBYTE -> {
-                        TODO("ror ubyte")
-                    }
-                    DataType.UWORD -> {
-                        TODO("ror uword")
-                    }
-                    else -> throw AssemblyError("weird type")
-                }
-            }
-            "ror2" -> {
-                // in-place
-                val what = fcall.arglist.single()
-                val dt = what.inferType(program)!!
-                when(dt) {
-                    DataType.UBYTE -> {
-                        TODO("ror2 ubyte")
-                    }
-                    DataType.UWORD -> {
-                        TODO("ror2 uword")
-                    }
-                    else -> throw AssemblyError("weird type")
-                }
-            }
-            else -> {
-                translateFunctionArguments(fcall.arglist, func)
-                asmgen.out("  jsr  prog8_lib.func_$functionName")
-            }
-        }
-    }
-
-    private fun translateFunctionArguments(args: MutableList<Expression>, signature: FunctionSignature) {
-        args.forEach {
-            asmgen.translateExpression(it)
-        }
-    }
-
-}
-

compiler/src/prog8/functions/BuiltinFunctions.kt

@@ -7,131 +7,134 @@ import prog8.compiler.CompilerException
 import kotlin.math.*
 
 
-class BuiltinFunctionParam(val name: String, val possibleDatatypes: Set<DataType>)
+class FParam(val name: String, val possibleDatatypes: Set<DataType>)
 
 
 typealias ConstExpressionCaller = (args: List<Expression>, position: Position, program: Program) -> NumericLiteralValue
 
 
-class FunctionSignature(val pure: Boolean,      // does it have side effects?
-                        val parameters: List<BuiltinFunctionParam>,
-                        val returntype: DataType?,
-                        val constExpressionFunc: ConstExpressionCaller? = null)
+class FSignature(val pure: Boolean,      // does it have side effects?
+                 val parameters: List<FParam>,
+                 val returntype: DataType?,
+                 val constExpressionFunc: ConstExpressionCaller? = null)
 
 
 val BuiltinFunctions = mapOf(
         // this set of function have no return value and operate in-place:
-    "rol"         to FunctionSignature(false, listOf(BuiltinFunctionParam("item", setOf(DataType.UBYTE, DataType.UWORD))), null),
-    "ror"         to FunctionSignature(false, listOf(BuiltinFunctionParam("item", setOf(DataType.UBYTE, DataType.UWORD))), null),
-    "rol2"        to FunctionSignature(false, listOf(BuiltinFunctionParam("item", setOf(DataType.UBYTE, DataType.UWORD))), null),
-    "ror2"        to FunctionSignature(false, listOf(BuiltinFunctionParam("item", setOf(DataType.UBYTE, DataType.UWORD))), null),
-    "lsl"         to FunctionSignature(false, listOf(BuiltinFunctionParam("item", IntegerDatatypes)), null),
-    "lsr"         to FunctionSignature(false, listOf(BuiltinFunctionParam("item", IntegerDatatypes)), null),
+    "rol"         to FSignature(false, listOf(FParam("item", setOf(DataType.UBYTE, DataType.UWORD))), null),
+    "ror"         to FSignature(false, listOf(FParam("item", setOf(DataType.UBYTE, DataType.UWORD))), null),
+    "rol2"        to FSignature(false, listOf(FParam("item", setOf(DataType.UBYTE, DataType.UWORD))), null),
+    "ror2"        to FSignature(false, listOf(FParam("item", setOf(DataType.UBYTE, DataType.UWORD))), null),
+    "lsl"         to FSignature(false, listOf(FParam("item", IntegerDatatypes)), null),
+    "lsr"         to FSignature(false, listOf(FParam("item", IntegerDatatypes)), null),
+    "sort"        to FSignature(false, listOf(FParam("array", ArrayDatatypes)), null),
+    "reverse"     to FSignature(false, listOf(FParam("array", ArrayDatatypes)), null),
         // these few have a return value depending on the argument(s):
-    "max"         to FunctionSignature(true, listOf(BuiltinFunctionParam("values", ArrayDatatypes)), null) { a, p, _ -> collectionArgNeverConst(a, p) },    // type depends on args
-    "min"         to FunctionSignature(true, listOf(BuiltinFunctionParam("values", ArrayDatatypes)), null) { a, p, _ -> collectionArgNeverConst(a, p) },    // type depends on args
-    "sum"         to FunctionSignature(true, listOf(BuiltinFunctionParam("values", ArrayDatatypes)), null) { a, p, _ -> collectionArgNeverConst(a, p) },      // type depends on args
-    "abs"         to FunctionSignature(true, listOf(BuiltinFunctionParam("value", NumericDatatypes)), null, ::builtinAbs),      // type depends on argument
-    "len"         to FunctionSignature(true, listOf(BuiltinFunctionParam("values", IterableDatatypes)), null, ::builtinLen),    // type is UBYTE or UWORD depending on actual length
+    "max"         to FSignature(true, listOf(FParam("values", ArrayDatatypes)), null) { a, p, prg -> collectionArg(a, p, prg, ::builtinMax) },    // type depends on args
+    "min"         to FSignature(true, listOf(FParam("values", ArrayDatatypes)), null) { a, p, prg -> collectionArg(a, p, prg, ::builtinMin) },    // type depends on args
+    "sum"         to FSignature(true, listOf(FParam("values", ArrayDatatypes)), null) { a, p, prg -> collectionArg(a, p, prg, ::builtinSum) },      // type depends on args
+    "abs"         to FSignature(true, listOf(FParam("value", NumericDatatypes)), null, ::builtinAbs),      // type depends on argument
+    "len"         to FSignature(true, listOf(FParam("values", IterableDatatypes)), null, ::builtinLen),    // type is UBYTE or UWORD depending on actual length
         // normal functions follow:
-    "sin"         to FunctionSignature(true, listOf(BuiltinFunctionParam("rads", setOf(DataType.FLOAT))), DataType.FLOAT) { a, p, prg -> oneDoubleArg(a, p, prg, Math::sin) },
-    "sin8"        to FunctionSignature(true, listOf(BuiltinFunctionParam("angle8", setOf(DataType.UBYTE))), DataType.BYTE, ::builtinSin8 ),
-    "sin8u"       to FunctionSignature(true, listOf(BuiltinFunctionParam("angle8", setOf(DataType.UBYTE))), DataType.UBYTE, ::builtinSin8u ),
-    "sin16"       to FunctionSignature(true, listOf(BuiltinFunctionParam("angle8", setOf(DataType.UBYTE))), DataType.WORD, ::builtinSin16 ),
-    "sin16u"      to FunctionSignature(true, listOf(BuiltinFunctionParam("angle8", setOf(DataType.UBYTE))), DataType.UWORD, ::builtinSin16u ),
-    "cos"         to FunctionSignature(true, listOf(BuiltinFunctionParam("rads", setOf(DataType.FLOAT))), DataType.FLOAT) { a, p, prg -> oneDoubleArg(a, p, prg, Math::cos) },
-    "cos8"        to FunctionSignature(true, listOf(BuiltinFunctionParam("angle8", setOf(DataType.UBYTE))), DataType.BYTE, ::builtinCos8 ),
-    "cos8u"       to FunctionSignature(true, listOf(BuiltinFunctionParam("angle8", setOf(DataType.UBYTE))), DataType.UBYTE, ::builtinCos8u ),
-    "cos16"       to FunctionSignature(true, listOf(BuiltinFunctionParam("angle8", setOf(DataType.UBYTE))), DataType.WORD, ::builtinCos16 ),
-    "cos16u"      to FunctionSignature(true, listOf(BuiltinFunctionParam("angle8", setOf(DataType.UBYTE))), DataType.UWORD, ::builtinCos16u ),
-    "tan"         to FunctionSignature(true, listOf(BuiltinFunctionParam("rads", setOf(DataType.FLOAT))), DataType.FLOAT) { a, p, prg -> oneDoubleArg(a, p, prg, Math::tan) },
-    "atan"        to FunctionSignature(true, listOf(BuiltinFunctionParam("rads", setOf(DataType.FLOAT))), DataType.FLOAT) { a, p, prg -> oneDoubleArg(a, p, prg, Math::atan) },
-    "ln"          to FunctionSignature(true, listOf(BuiltinFunctionParam("value", setOf(DataType.FLOAT))), DataType.FLOAT) { a, p, prg -> oneDoubleArg(a, p, prg, Math::log) },
-    "log2"        to FunctionSignature(true, listOf(BuiltinFunctionParam("value", setOf(DataType.FLOAT))), DataType.FLOAT) { a, p, prg -> oneDoubleArg(a, p, prg, ::log2) },
-    "sqrt16"      to FunctionSignature(true, listOf(BuiltinFunctionParam("value", setOf(DataType.UWORD))), DataType.UBYTE) { a, p, prg -> oneIntArgOutputInt(a, p, prg) { sqrt(it.toDouble()).toInt() } },
-    "sqrt"        to FunctionSignature(true, listOf(BuiltinFunctionParam("value", setOf(DataType.FLOAT))), DataType.FLOAT) { a, p, prg -> oneDoubleArg(a, p, prg, Math::sqrt) },
-    "rad"         to FunctionSignature(true, listOf(BuiltinFunctionParam("value", setOf(DataType.FLOAT))), DataType.FLOAT) { a, p, prg -> oneDoubleArg(a, p, prg, Math::toRadians) },
-    "deg"         to FunctionSignature(true, listOf(BuiltinFunctionParam("value", setOf(DataType.FLOAT))), DataType.FLOAT) { a, p, prg -> oneDoubleArg(a, p, prg, Math::toDegrees) },
-    "avg"         to FunctionSignature(true, listOf(BuiltinFunctionParam("values", ArrayDatatypes)), DataType.FLOAT) { a, p, _ -> collectionArgNeverConst(a, p) },
-    "round"       to FunctionSignature(true, listOf(BuiltinFunctionParam("value", setOf(DataType.FLOAT))), DataType.FLOAT) { a, p, prg -> oneDoubleArgOutputWord(a, p, prg, Math::round) },
-    "floor"       to FunctionSignature(true, listOf(BuiltinFunctionParam("value", setOf(DataType.FLOAT))), DataType.FLOAT) { a, p, prg -> oneDoubleArgOutputWord(a, p, prg, Math::floor) },
-    "ceil"        to FunctionSignature(true, listOf(BuiltinFunctionParam("value", setOf(DataType.FLOAT))), DataType.FLOAT) { a, p, prg -> oneDoubleArgOutputWord(a, p, prg, Math::ceil) },
-    "any"         to FunctionSignature(true, listOf(BuiltinFunctionParam("values", ArrayDatatypes)), DataType.UBYTE) { a, p, _ -> collectionArgNeverConst(a, p) },
-    "all"         to FunctionSignature(true, listOf(BuiltinFunctionParam("values", ArrayDatatypes)), DataType.UBYTE) { a, p, _ -> collectionArgNeverConst(a, p) },
-    "lsb"         to FunctionSignature(true, listOf(BuiltinFunctionParam("value", setOf(DataType.UWORD, DataType.WORD))), DataType.UBYTE) { a, p, prg -> oneIntArgOutputInt(a, p, prg) { x: Int -> x and 255 }},
-    "msb"         to FunctionSignature(true, listOf(BuiltinFunctionParam("value", setOf(DataType.UWORD, DataType.WORD))), DataType.UBYTE) { a, p, prg -> oneIntArgOutputInt(a, p, prg) { x: Int -> x ushr 8 and 255}},
-    "mkword"      to FunctionSignature(true, listOf(
-                                                        BuiltinFunctionParam("lsb", setOf(DataType.UBYTE)),
-                                                        BuiltinFunctionParam("msb", setOf(DataType.UBYTE))), DataType.UWORD, ::builtinMkword),
-    "rnd"         to FunctionSignature(true, emptyList(), DataType.UBYTE),
-    "rndw"        to FunctionSignature(true, emptyList(), DataType.UWORD),
-    "rndf"        to FunctionSignature(true, emptyList(), DataType.FLOAT),
-    "rsave"       to FunctionSignature(false, emptyList(), null),
-    "rrestore"    to FunctionSignature(false, emptyList(), null),
-    "set_carry"   to FunctionSignature(false, emptyList(), null),
-    "clear_carry" to FunctionSignature(false, emptyList(), null),
-    "set_irqd"    to FunctionSignature(false, emptyList(), null),
-    "clear_irqd"  to FunctionSignature(false, emptyList(), null),
-    "read_flags"  to FunctionSignature(false, emptyList(), DataType.UBYTE),
-    "swap"        to FunctionSignature(false, listOf(BuiltinFunctionParam("first", NumericDatatypes), BuiltinFunctionParam("second", NumericDatatypes)), null),
-    "memcopy"     to FunctionSignature(false, listOf(
-                                                        BuiltinFunctionParam("from", IterableDatatypes + setOf(DataType.UWORD)),
-                                                        BuiltinFunctionParam("to", IterableDatatypes + setOf(DataType.UWORD)),
-                                                        BuiltinFunctionParam("numbytes", setOf(DataType.UBYTE))), null),
-    "memset"      to FunctionSignature(false, listOf(
-                                                        BuiltinFunctionParam("address", IterableDatatypes + setOf(DataType.UWORD)),
-                                                        BuiltinFunctionParam("numbytes", setOf(DataType.UWORD)),
-                                                        BuiltinFunctionParam("bytevalue", ByteDatatypes)), null),
-    "memsetw"     to FunctionSignature(false, listOf(
-                                                        BuiltinFunctionParam("address", IterableDatatypes + setOf(DataType.UWORD)),
-                                                        BuiltinFunctionParam("numwords", setOf(DataType.UWORD)),
-                                                        BuiltinFunctionParam("wordvalue", setOf(DataType.UWORD, DataType.WORD))), null),
-    "strlen"      to FunctionSignature(true, listOf(BuiltinFunctionParam("string", StringDatatypes)), DataType.UBYTE, ::builtinStrlen),
-    "vm_write_memchr"  to FunctionSignature(false, listOf(BuiltinFunctionParam("address", setOf(DataType.UWORD))), null),
-    "vm_write_memstr"  to FunctionSignature(false, listOf(BuiltinFunctionParam("address", setOf(DataType.UWORD))), null),
-    "vm_write_num"     to FunctionSignature(false, listOf(BuiltinFunctionParam("number", NumericDatatypes)), null),
-    "vm_write_char"    to FunctionSignature(false, listOf(BuiltinFunctionParam("char", setOf(DataType.UBYTE))), null),
-    "vm_write_str"     to FunctionSignature(false, listOf(BuiltinFunctionParam("string", StringDatatypes)), null),
-    "vm_input_str"     to FunctionSignature(false, listOf(BuiltinFunctionParam("intovar", StringDatatypes)), null),
-    "vm_gfx_clearscr"  to FunctionSignature(false, listOf(BuiltinFunctionParam("color", setOf(DataType.UBYTE))), null),
-    "vm_gfx_pixel"     to FunctionSignature(false, listOf(
-                                                        BuiltinFunctionParam("x", IntegerDatatypes),
-                                                        BuiltinFunctionParam("y", IntegerDatatypes),
-                                                        BuiltinFunctionParam("color", IntegerDatatypes)), null),
-    "vm_gfx_line"     to FunctionSignature(false, listOf(
-                                                        BuiltinFunctionParam("x1", IntegerDatatypes),
-                                                        BuiltinFunctionParam("y1", IntegerDatatypes),
-                                                        BuiltinFunctionParam("x2", IntegerDatatypes),
-                                                        BuiltinFunctionParam("y2", IntegerDatatypes),
-                                                        BuiltinFunctionParam("color", IntegerDatatypes)), null),
-    "vm_gfx_text"      to FunctionSignature(false, listOf(
-                                                        BuiltinFunctionParam("x", IntegerDatatypes),
-                                                        BuiltinFunctionParam("y", IntegerDatatypes),
-                                                        BuiltinFunctionParam("color", IntegerDatatypes),
-                                                        BuiltinFunctionParam("text", StringDatatypes)),
-                                                        null)
+    "sgn"         to FSignature(true, listOf(FParam("value", NumericDatatypes)), DataType.BYTE, ::builtinSgn ),
+    "sin"         to FSignature(true, listOf(FParam("rads", setOf(DataType.FLOAT))), DataType.FLOAT) { a, p, prg -> oneDoubleArg(a, p, prg, Math::sin) },
+    "sin8"        to FSignature(true, listOf(FParam("angle8", setOf(DataType.UBYTE))), DataType.BYTE, ::builtinSin8 ),
+    "sin8u"       to FSignature(true, listOf(FParam("angle8", setOf(DataType.UBYTE))), DataType.UBYTE, ::builtinSin8u ),
+    "sin16"       to FSignature(true, listOf(FParam("angle8", setOf(DataType.UBYTE))), DataType.WORD, ::builtinSin16 ),
+    "sin16u"      to FSignature(true, listOf(FParam("angle8", setOf(DataType.UBYTE))), DataType.UWORD, ::builtinSin16u ),
+    "cos"         to FSignature(true, listOf(FParam("rads", setOf(DataType.FLOAT))), DataType.FLOAT) { a, p, prg -> oneDoubleArg(a, p, prg, Math::cos) },
+    "cos8"        to FSignature(true, listOf(FParam("angle8", setOf(DataType.UBYTE))), DataType.BYTE, ::builtinCos8 ),
+    "cos8u"       to FSignature(true, listOf(FParam("angle8", setOf(DataType.UBYTE))), DataType.UBYTE, ::builtinCos8u ),
+    "cos16"       to FSignature(true, listOf(FParam("angle8", setOf(DataType.UBYTE))), DataType.WORD, ::builtinCos16 ),
+    "cos16u"      to FSignature(true, listOf(FParam("angle8", setOf(DataType.UBYTE))), DataType.UWORD, ::builtinCos16u ),
+    "tan"         to FSignature(true, listOf(FParam("rads", setOf(DataType.FLOAT))), DataType.FLOAT) { a, p, prg -> oneDoubleArg(a, p, prg, Math::tan) },
+    "atan"        to FSignature(true, listOf(FParam("rads", setOf(DataType.FLOAT))), DataType.FLOAT) { a, p, prg -> oneDoubleArg(a, p, prg, Math::atan) },
+    "ln"          to FSignature(true, listOf(FParam("value", setOf(DataType.FLOAT))), DataType.FLOAT) { a, p, prg -> oneDoubleArg(a, p, prg, Math::log) },
+    "log2"        to FSignature(true, listOf(FParam("value", setOf(DataType.FLOAT))), DataType.FLOAT) { a, p, prg -> oneDoubleArg(a, p, prg, ::log2) },
+    "sqrt16"      to FSignature(true, listOf(FParam("value", setOf(DataType.UWORD))), DataType.UBYTE) { a, p, prg -> oneIntArgOutputInt(a, p, prg) { sqrt(it.toDouble()).toInt() } },
+    "sqrt"        to FSignature(true, listOf(FParam("value", setOf(DataType.FLOAT))), DataType.FLOAT) { a, p, prg -> oneDoubleArg(a, p, prg, Math::sqrt) },
+    "rad"         to FSignature(true, listOf(FParam("value", setOf(DataType.FLOAT))), DataType.FLOAT) { a, p, prg -> oneDoubleArg(a, p, prg, Math::toRadians) },
+    "deg"         to FSignature(true, listOf(FParam("value", setOf(DataType.FLOAT))), DataType.FLOAT) { a, p, prg -> oneDoubleArg(a, p, prg, Math::toDegrees) },
+    "round"       to FSignature(true, listOf(FParam("value", setOf(DataType.FLOAT))), DataType.FLOAT) { a, p, prg -> oneDoubleArgOutputWord(a, p, prg, Math::round) },
+    "floor"       to FSignature(true, listOf(FParam("value", setOf(DataType.FLOAT))), DataType.FLOAT) { a, p, prg -> oneDoubleArgOutputWord(a, p, prg, Math::floor) },
+    "ceil"        to FSignature(true, listOf(FParam("value", setOf(DataType.FLOAT))), DataType.FLOAT) { a, p, prg -> oneDoubleArgOutputWord(a, p, prg, Math::ceil) },
+    "any"         to FSignature(true, listOf(FParam("values", ArrayDatatypes)), DataType.UBYTE) { a, p, prg -> collectionArg(a, p, prg, ::builtinAny) },
+    "all"         to FSignature(true, listOf(FParam("values", ArrayDatatypes)), DataType.UBYTE) { a, p, prg -> collectionArg(a, p, prg, ::builtinAll) },
+    "lsb"         to FSignature(true, listOf(FParam("value", setOf(DataType.UWORD, DataType.WORD))), DataType.UBYTE) { a, p, prg -> oneIntArgOutputInt(a, p, prg) { x: Int -> x and 255 }},
+    "msb"         to FSignature(true, listOf(FParam("value", setOf(DataType.UWORD, DataType.WORD))), DataType.UBYTE) { a, p, prg -> oneIntArgOutputInt(a, p, prg) { x: Int -> x ushr 8 and 255}},
+    "mkword"      to FSignature(true, listOf(FParam("lsb", setOf(DataType.UBYTE)), FParam("msb", setOf(DataType.UBYTE))), DataType.UWORD, ::builtinMkword),
+    "rnd"         to FSignature(true, emptyList(), DataType.UBYTE),
+    "rndw"        to FSignature(true, emptyList(), DataType.UWORD),
+    "rndf"        to FSignature(true, emptyList(), DataType.FLOAT),
+    "exit"        to FSignature(false, listOf(FParam("returnvalue", setOf(DataType.UBYTE))), null),
+    "rsave"       to FSignature(false, emptyList(), null),
+    "rrestore"    to FSignature(false, emptyList(), null),
+    "set_carry"   to FSignature(false, emptyList(), null),
+    "clear_carry" to FSignature(false, emptyList(), null),
+    "set_irqd"    to FSignature(false, emptyList(), null),
+    "clear_irqd"  to FSignature(false, emptyList(), null),
+    "read_flags"  to FSignature(false, emptyList(), DataType.UBYTE),
+    "swap"        to FSignature(false, listOf(FParam("first", NumericDatatypes), FParam("second", NumericDatatypes)), null),
+    "memcopy"     to FSignature(false, listOf(
+                            FParam("from", IterableDatatypes + DataType.UWORD),
+                            FParam("to", IterableDatatypes + DataType.UWORD),
+                            FParam("numbytes", setOf(DataType.UBYTE))), null),
+    "memset"      to FSignature(false, listOf(
+                            FParam("address", IterableDatatypes + DataType.UWORD),
+                            FParam("numbytes", setOf(DataType.UWORD)),
+                            FParam("bytevalue", ByteDatatypes)), null),
+    "memsetw"     to FSignature(false, listOf(
+                            FParam("address", IterableDatatypes + DataType.UWORD),
+                            FParam("numwords", setOf(DataType.UWORD)),
+                            FParam("wordvalue", setOf(DataType.UWORD, DataType.WORD))), null),
+    "strlen"      to FSignature(true, listOf(FParam("string", setOf(DataType.STR))), DataType.UBYTE, ::builtinStrlen),
+    "substr"      to FSignature(false, listOf(
+            FParam("source", IterableDatatypes + DataType.UWORD),
+            FParam("target", IterableDatatypes + DataType.UWORD),
+            FParam("start", setOf(DataType.UBYTE)),
+            FParam("length", setOf(DataType.UBYTE))), null),
+    "leftstr"      to FSignature(false, listOf(
+            FParam("source", IterableDatatypes + DataType.UWORD),
+            FParam("target", IterableDatatypes + DataType.UWORD),
+            FParam("length", setOf(DataType.UBYTE))), null),
+    "rightstr"      to FSignature(false, listOf(
+            FParam("source", IterableDatatypes + DataType.UWORD),
+            FParam("target", IterableDatatypes + DataType.UWORD),
+            FParam("length", setOf(DataType.UBYTE))), null)
 )
 
+fun builtinMax(array: List<Number>): Number = array.maxByOrNull { it.toDouble() }!!
 
-fun builtinFunctionReturnType(function: String, args: List<Expression>, program: Program): DataType? {
+fun builtinMin(array: List<Number>): Number = array.minByOrNull { it.toDouble() }!!
+
+fun builtinSum(array: List<Number>): Number = array.sumByDouble { it.toDouble() }
+
+fun builtinAny(array: List<Number>): Number = if(array.any { it.toDouble()!=0.0 }) 1 else 0
+
+fun builtinAll(array: List<Number>): Number = if(array.all { it.toDouble()!=0.0 }) 1 else 0
+
+
+fun builtinFunctionReturnType(function: String, args: List<Expression>, program: Program): InferredTypes.InferredType {
 
     fun datatypeFromIterableArg(arglist: Expression): DataType {
-        if(arglist is ReferenceLiteralValue) {
-            if(arglist.type== DataType.ARRAY_UB || arglist.type== DataType.ARRAY_UW || arglist.type== DataType.ARRAY_F) {
-                val dt = arglist.array!!.map {it.inferType(program)}
-                if(dt.any { it!= DataType.UBYTE && it!= DataType.UWORD && it!= DataType.FLOAT}) {
-                    throw FatalAstException("fuction $function only accepts arraysize of numeric values")
-                }
-                if(dt.any { it== DataType.FLOAT }) return DataType.FLOAT
-                if(dt.any { it== DataType.UWORD }) return DataType.UWORD
-                return DataType.UBYTE
+        if(arglist is ArrayLiteralValue) {
+            val dt = arglist.value.map {it.inferType(program).typeOrElse(DataType.STRUCT)}.toSet()
+            if(dt.any { it !in NumericDatatypes }) {
+                throw FatalAstException("fuction $function only accepts array of numeric values")
             }
+            if(DataType.FLOAT in dt) return DataType.FLOAT
+            if(DataType.UWORD in dt) return DataType.UWORD
+            if(DataType.WORD in dt) return DataType.WORD
+            if(DataType.BYTE in dt) return DataType.BYTE
+            return DataType.UBYTE
         }
         if(arglist is IdentifierReference) {
-            return when(val dt = arglist.inferType(program)) {
-                in NumericDatatypes -> dt!!
-                in StringDatatypes -> dt!!
-                in ArrayDatatypes -> ArrayElementTypes.getValue(dt!!)
+            val idt = arglist.inferType(program)
+            if(!idt.isKnown)
+                throw FatalAstException("couldn't determine type of iterable $arglist")
+            return when(val dt = idt.typeOrElse(DataType.STRUCT)) {
+                DataType.STR, in NumericDatatypes -> dt
+                in ArrayDatatypes -> ArrayElementTypes.getValue(dt)
                 else -> throw FatalAstException("function '$function' requires one argument which is an iterable")
             }
         }
@@ -140,48 +143,49 @@ fun builtinFunctionReturnType(function: String, args: List<Expression>, program:
 
     val func = BuiltinFunctions.getValue(function)
     if(func.returntype!=null)
-        return func.returntype
+        return InferredTypes.knownFor(func.returntype)
     // function has return values, but the return type depends on the arguments
 
     return when (function) {
         "abs" -> {
             val dt = args.single().inferType(program)
-            if(dt in NumericDatatypes)
+            if(dt.typeOrElse(DataType.STRUCT) in NumericDatatypes)
                 return dt
             else
                 throw FatalAstException("weird datatype passed to abs $dt")
         }
         "max", "min" -> {
             when(val dt = datatypeFromIterableArg(args.single())) {
-                in NumericDatatypes -> dt
-                in StringDatatypes -> DataType.UBYTE
-                in ArrayDatatypes -> ArrayElementTypes.getValue(dt)
-                else -> null
+                DataType.STR -> InferredTypes.knownFor(DataType.UBYTE)
+                in NumericDatatypes -> InferredTypes.knownFor(dt)
+                in ArrayDatatypes -> InferredTypes.knownFor(ArrayElementTypes.getValue(dt))
+                else -> InferredTypes.unknown()
             }
         }
         "sum" -> {
             when(datatypeFromIterableArg(args.single())) {
-                DataType.UBYTE, DataType.UWORD -> DataType.UWORD
-                DataType.BYTE, DataType.WORD -> DataType.WORD
-                DataType.FLOAT -> DataType.FLOAT
-                DataType.ARRAY_UB, DataType.ARRAY_UW -> DataType.UWORD
-                DataType.ARRAY_B, DataType.ARRAY_W -> DataType.WORD
-                DataType.ARRAY_F -> DataType.FLOAT
-                in StringDatatypes -> DataType.UWORD
-                else -> null
+                DataType.UBYTE, DataType.UWORD -> InferredTypes.knownFor(DataType.UWORD)
+                DataType.BYTE, DataType.WORD -> InferredTypes.knownFor(DataType.WORD)
+                DataType.FLOAT -> InferredTypes.knownFor(DataType.FLOAT)
+                DataType.ARRAY_UB, DataType.ARRAY_UW -> InferredTypes.knownFor(DataType.UWORD)
+                DataType.ARRAY_B, DataType.ARRAY_W -> InferredTypes.knownFor(DataType.WORD)
+                DataType.ARRAY_F -> InferredTypes.knownFor(DataType.FLOAT)
+                DataType.STR -> InferredTypes.knownFor(DataType.UWORD)
+                else -> InferredTypes.unknown()
             }
         }
         "len" -> {
             // a length can be >255 so in that case, the result is an UWORD instead of an UBYTE
             // but to avoid a lot of code duplication we simply assume UWORD in all cases for now
-            return DataType.UWORD
+            return InferredTypes.knownFor(DataType.UWORD)
         }
-        else -> return null
+        else -> return InferredTypes.unknown()
     }
 }
 
 
 class NotConstArgumentException: AstException("not a const argument to a built-in function")
+class CannotEvaluateException(func:String, msg: String): FatalAstException("cannot evaluate built-in function $func: $msg")
 
 
 private fun oneDoubleArg(args: List<Expression>, position: Position, program: Program, function: (arg: Double)->Number): NumericLiteralValue {
@@ -211,12 +215,16 @@ private fun oneIntArgOutputInt(args: List<Expression>, position: Position, progr
     return numericLiteral(function(integer).toInt(), args[0].position)
 }
 
-private fun collectionArgNeverConst(args: List<Expression>, position: Position): NumericLiteralValue {
+private fun collectionArg(args: List<Expression>, position: Position, program: Program, function: (arg: List<Number>)->Number): NumericLiteralValue {
     if(args.size!=1)
         throw SyntaxError("builtin function requires one non-scalar argument", position)
 
-    // max/min/sum etc only work on arrays and these are never considered to be const for these functions
-    throw NotConstArgumentException()
+    val array= args[0] as? ArrayLiteralValue ?: throw NotConstArgumentException()
+    val constElements = array.value.map{it.constValue(program)?.number}
+    if(constElements.contains(null))
+        throw NotConstArgumentException()
+
+    return NumericLiteralValue.optimalNumeric(function(constElements.mapNotNull { it }), args[0].position)
 }
 
 private fun builtinAbs(args: List<Expression>, position: Position, program: Program): NumericLiteralValue {
@@ -236,7 +244,7 @@ private fun builtinStrlen(args: List<Expression>, position: Position, program: P
     if (args.size != 1)
         throw SyntaxError("strlen requires one argument", position)
     val argument = args[0].constValue(program) ?: throw NotConstArgumentException()
-    if(argument.type !in StringDatatypes)
+    if(argument.type != DataType.STR)
         throw SyntaxError("strlen must have string argument", position)
 
     throw NotConstArgumentException()       // this function is not considering the string argument a constant
@@ -254,28 +262,29 @@ private fun builtinLen(args: List<Expression>, position: Position, program: Prog
     var arraySize = directMemVar?.arraysize?.size()
     if(arraySize != null)
         return NumericLiteralValue.optimalInteger(arraySize, position)
+    if(args[0] is ArrayLiteralValue)
+        return NumericLiteralValue.optimalInteger((args[0] as ArrayLiteralValue).value.size, position)
     if(args[0] !is IdentifierReference)
         throw SyntaxError("len argument should be an identifier, but is ${args[0]}", position)
-    val target = (args[0] as IdentifierReference).targetVarDecl(program.namespace)!!
+    val target = (args[0] as IdentifierReference).targetVarDecl(program.namespace)
+            ?: throw CannotEvaluateException("len", "no target vardecl")
 
     return when(target.datatype) {
         DataType.ARRAY_UB, DataType.ARRAY_B, DataType.ARRAY_UW, DataType.ARRAY_W -> {
-            arraySize = target.arraysize!!.size()!!
-            if(arraySize>256)
-                throw CompilerException("array length exceeds byte limit ${target.position}")
+            arraySize = target.arraysize?.size()
+            if(arraySize==null)
+                throw CannotEvaluateException("len", "arraysize unknown")
             NumericLiteralValue.optimalInteger(arraySize, args[0].position)
         }
         DataType.ARRAY_F -> {
-            arraySize = target.arraysize!!.size()!!
-            if(arraySize>256)
-                throw CompilerException("array length exceeds byte limit ${target.position}")
+            arraySize = target.arraysize?.size()
+            if(arraySize==null)
+                throw CannotEvaluateException("len", "arraysize unknown")
             NumericLiteralValue.optimalInteger(arraySize, args[0].position)
         }
-        in StringDatatypes -> {
-            val refLv = target.value as ReferenceLiteralValue
-            if(refLv.str!!.length>255)
-                throw CompilerException("string length exceeds byte limit ${refLv.position}")
-            NumericLiteralValue.optimalInteger(refLv.str.length, args[0].position)
+        DataType.STR -> {
+            val refLv = target.value as StringLiteralValue
+            NumericLiteralValue.optimalInteger(refLv.value.length, args[0].position)
         }
         in NumericDatatypes -> throw SyntaxError("len of weird argument ${args[0]}", position)
         else -> throw CompilerException("weird datatype")
@@ -297,7 +306,7 @@ private fun builtinSin8(args: List<Expression>, position: Position, program: Pro
         throw SyntaxError("sin8 requires one argument", position)
     val constval = args[0].constValue(program) ?: throw NotConstArgumentException()
     val rad = constval.number.toDouble() /256.0 * 2.0 * PI
-    return NumericLiteralValue(DataType.BYTE, (127.0 * sin(rad)).toShort(), position)
+    return NumericLiteralValue(DataType.BYTE, (127.0 * sin(rad)).toInt().toShort(), position)
 }
 
 private fun builtinSin8u(args: List<Expression>, position: Position, program: Program): NumericLiteralValue {
@@ -305,7 +314,7 @@ private fun builtinSin8u(args: List<Expression>, position: Position, program: Pr
         throw SyntaxError("sin8u requires one argument", position)
     val constval = args[0].constValue(program) ?: throw NotConstArgumentException()
     val rad = constval.number.toDouble() /256.0 * 2.0 * PI
-    return NumericLiteralValue(DataType.UBYTE, (128.0 + 127.5 * sin(rad)).toShort(), position)
+    return NumericLiteralValue(DataType.UBYTE, (128.0 + 127.5 * sin(rad)).toInt().toShort(), position)
 }
 
 private fun builtinCos8(args: List<Expression>, position: Position, program: Program): NumericLiteralValue {
@@ -313,7 +322,7 @@ private fun builtinCos8(args: List<Expression>, position: Position, program: Pro
         throw SyntaxError("cos8 requires one argument", position)
     val constval = args[0].constValue(program) ?: throw NotConstArgumentException()
     val rad = constval.number.toDouble() /256.0 * 2.0 * PI
-    return NumericLiteralValue(DataType.BYTE, (127.0 * cos(rad)).toShort(), position)
+    return NumericLiteralValue(DataType.BYTE, (127.0 * cos(rad)).toInt().toShort(), position)
 }
 
 private fun builtinCos8u(args: List<Expression>, position: Position, program: Program): NumericLiteralValue {
@@ -321,7 +330,7 @@ private fun builtinCos8u(args: List<Expression>, position: Position, program: Pr
         throw SyntaxError("cos8u requires one argument", position)
     val constval = args[0].constValue(program) ?: throw NotConstArgumentException()
     val rad = constval.number.toDouble() /256.0 * 2.0 * PI
-    return NumericLiteralValue(DataType.UBYTE, (128.0 + 127.5 * cos(rad)).toShort(), position)
+    return NumericLiteralValue(DataType.UBYTE, (128.0 + 127.5 * cos(rad)).toInt().toShort(), position)
 }
 
 private fun builtinSin16(args: List<Expression>, position: Position, program: Program): NumericLiteralValue {
@@ -356,6 +365,13 @@ private fun builtinCos16u(args: List<Expression>, position: Position, program: P
     return NumericLiteralValue(DataType.UWORD, (32768.0 + 32767.5 * cos(rad)).toInt(), position)
 }
 
+private fun builtinSgn(args: List<Expression>, position: Position, program: Program): NumericLiteralValue {
+    if (args.size != 1)
+        throw SyntaxError("sgn requires one argument", position)
+    val constval = args[0].constValue(program) ?: throw NotConstArgumentException()
+    return NumericLiteralValue(DataType.BYTE, constval.number.toDouble().sign.toInt().toShort(), position)
+}
+
 private fun numericLiteral(value: Number, position: Position): NumericLiteralValue {
     val floatNum=value.toDouble()
     val tweakedValue: Number =

compiler/src/prog8/optimizer/CallGraph.kt

@@ -6,22 +6,30 @@ import prog8.ast.Node
 import prog8.ast.Program
 import prog8.ast.base.DataType
 import prog8.ast.base.ParentSentinel
-import prog8.ast.base.VarDeclType
-import prog8.ast.base.initvarsSubName
 import prog8.ast.expressions.FunctionCall
 import prog8.ast.expressions.IdentifierReference
 import prog8.ast.processing.IAstVisitor
 import prog8.ast.statements.*
 import prog8.compiler.loadAsmIncludeFile
 
+private val alwaysKeepSubroutines = setOf(
+        Pair("main", "start"),
+        Pair("irq", "irq"),
+        Pair("prog8_lib", "init_system")
+)
 
-class CallGraph(private val program: Program): IAstVisitor {
+private val asmJumpRx = Regex("""[\-+a-zA-Z0-9_ \t]+(jmp|jsr)[ \t]+(\S+).*""", RegexOption.IGNORE_CASE)
+private val asmRefRx = Regex("""[\-+a-zA-Z0-9_ \t]+(...)[ \t]+(\S+).*""", RegexOption.IGNORE_CASE)
 
-    val modulesImporting = mutableMapOf<Module, List<Module>>().withDefault { mutableListOf() }
-    val modulesImportedBy = mutableMapOf<Module, List<Module>>().withDefault { mutableListOf() }
-    val subroutinesCalling = mutableMapOf<INameScope, List<Subroutine>>().withDefault { mutableListOf() }
-    val subroutinesCalledBy = mutableMapOf<Subroutine, List<Node>>().withDefault { mutableListOf() }
-    // TODO  add dataflow graph: what statements use what variables
+
+class CallGraph(private val program: Program) : IAstVisitor {
+
+    val imports = mutableMapOf<Module, List<Module>>().withDefault { mutableListOf() }
+    val importedBy = mutableMapOf<Module, List<Module>>().withDefault { mutableListOf() }
+    val calls = mutableMapOf<INameScope, List<Subroutine>>().withDefault { mutableListOf() }
+    val calledBy = mutableMapOf<Subroutine, List<Node>>().withDefault { mutableListOf() }
+
+    // TODO  add dataflow graph: what statements use what variables - can be used to eliminate unused vars
     val usedSymbols = mutableSetOf<Statement>()
 
     init {
@@ -31,9 +39,9 @@ class CallGraph(private val program: Program): IAstVisitor {
     fun forAllSubroutines(scope: INameScope, sub: (s: Subroutine) -> Unit) {
         fun findSubs(scope: INameScope) {
             scope.statements.forEach {
-                if(it is Subroutine)
+                if (it is Subroutine)
                     sub(it)
-                if(it is INameScope)
+                if (it is INameScope)
                     findSubs(it)
             }
         }
@@ -47,17 +55,8 @@ class CallGraph(private val program: Program): IAstVisitor {
             it.importedBy.clear()
             it.imports.clear()
 
-            it.importedBy.addAll(modulesImportedBy.getValue(it))
-            it.imports.addAll(modulesImporting.getValue(it))
-
-            forAllSubroutines(it) { sub ->
-                sub.calledBy.clear()
-                sub.calls.clear()
-
-                sub.calledBy.addAll(subroutinesCalledBy.getValue(sub))
-                sub.calls.addAll(subroutinesCalling.getValue(sub))
-            }
-
+            it.importedBy.addAll(importedBy.getValue(it))
+            it.imports.addAll(imports.getValue(it))
         }
 
         val rootmodule = program.modules.first()
@@ -65,7 +64,7 @@ class CallGraph(private val program: Program): IAstVisitor {
     }
 
     override fun visit(block: Block) {
-        if(block.definingModule().isLibraryModule) {
+        if (block.definingModule().isLibraryModule) {
             // make sure the block is not removed
             addNodeAndParentScopes(block)
         }
@@ -75,11 +74,11 @@ class CallGraph(private val program: Program): IAstVisitor {
 
     override fun visit(directive: Directive) {
         val thisModule = directive.definingModule()
-        if(directive.directive=="%import") {
-            val importedModule: Module = program.modules.single { it.name==directive.args[0].name }
-            modulesImporting[thisModule] = modulesImporting.getValue(thisModule).plus(importedModule)
-            modulesImportedBy[importedModule] = modulesImportedBy.getValue(importedModule).plus(thisModule)
-        } else if (directive.directive=="%asminclude") {
+        if (directive.directive == "%import") {
+            val importedModule: Module = program.modules.single { it.name == directive.args[0].name }
+            imports[thisModule] = imports.getValue(thisModule).plus(importedModule)
+            importedBy[importedModule] = importedBy.getValue(importedModule).plus(thisModule)
+        } else if (directive.directive == "%asminclude") {
             val asm = loadAsmIncludeFile(directive.args[0].str!!, thisModule.source)
             val scope = directive.definingScope()
             scanAssemblyCode(asm, directive, scope)
@@ -91,7 +90,7 @@ class CallGraph(private val program: Program): IAstVisitor {
     override fun visit(identifier: IdentifierReference) {
         // track symbol usage
         val target = identifier.targetStatement(this.program.namespace)
-        if(target!=null) {
+        if (target != null) {
             addNodeAndParentScopes(target)
         }
         super.visit(identifier)
@@ -99,24 +98,18 @@ class CallGraph(private val program: Program): IAstVisitor {
 
     private fun addNodeAndParentScopes(stmt: Statement) {
         usedSymbols.add(stmt)
-        var node: Node=stmt
+        var node: Node = stmt
         do {
-            if(node is INameScope && node is Statement) {
+            if (node is INameScope && node is Statement) {
                 usedSymbols.add(node)
             }
-            node=node.parent
+            node = node.parent
         } while (node !is Module && node !is ParentSentinel)
     }
 
     override fun visit(subroutine: Subroutine) {
-        val alwaysKeepSubroutines = setOf(
-                Pair("main", "start"),
-                Pair("irq", "irq"),
-                Pair("prog8_lib", "init_system")
-        )
-
-        if(Pair(subroutine.definingScope().name, subroutine.name) in alwaysKeepSubroutines
-                || subroutine.name== initvarsSubName || subroutine.definingModule().isLibraryModule) {
+        if (Pair(subroutine.definingScope().name, subroutine.name) in alwaysKeepSubroutines
+                || subroutine.definingModule().isLibraryModule) {
             // make sure the entrypoint is mentioned in the used symbols
             addNodeAndParentScopes(subroutine)
         }
@@ -124,12 +117,12 @@ class CallGraph(private val program: Program): IAstVisitor {
     }
 
     override fun visit(decl: VarDecl) {
-        if(decl.autogeneratedDontRemove || (decl.definingModule().isLibraryModule && decl.type!=VarDeclType.VAR)) {
-            // make sure autogenerated vardecls are in the used symbols
+        if (decl.autogeneratedDontRemove || decl.definingModule().isLibraryModule) {
+            // make sure autogenerated vardecls are in the used symbols and are never removed as 'unused'
             addNodeAndParentScopes(decl)
         }
 
-        if(decl.datatype==DataType.STRUCT)
+        if (decl.datatype == DataType.STRUCT)
             addNodeAndParentScopes(decl)
 
         super.visit(decl)
@@ -137,10 +130,10 @@ class CallGraph(private val program: Program): IAstVisitor {
 
     override fun visit(functionCall: FunctionCall) {
         val otherSub = functionCall.target.targetSubroutine(program.namespace)
-        if(otherSub!=null) {
+        if (otherSub != null) {
             functionCall.definingSubroutine()?.let { thisSub ->
-                subroutinesCalling[thisSub] = subroutinesCalling.getValue(thisSub).plus(otherSub)
-                subroutinesCalledBy[otherSub] = subroutinesCalledBy.getValue(otherSub).plus(functionCall)
+                calls[thisSub] = calls.getValue(thisSub).plus(otherSub)
+                calledBy[otherSub] = calledBy.getValue(otherSub).plus(functionCall)
             }
         }
         super.visit(functionCall)
@@ -148,10 +141,10 @@ class CallGraph(private val program: Program): IAstVisitor {
 
     override fun visit(functionCallStatement: FunctionCallStatement) {
         val otherSub = functionCallStatement.target.targetSubroutine(program.namespace)
-        if(otherSub!=null) {
+        if (otherSub != null) {
             functionCallStatement.definingSubroutine()?.let { thisSub ->
-                subroutinesCalling[thisSub] = subroutinesCalling.getValue(thisSub).plus(otherSub)
-                subroutinesCalledBy[otherSub] = subroutinesCalledBy.getValue(otherSub).plus(functionCallStatement)
+                calls[thisSub] = calls.getValue(thisSub).plus(otherSub)
+                calledBy[otherSub] = calledBy.getValue(otherSub).plus(functionCallStatement)
             }
         }
         super.visit(functionCallStatement)
@@ -159,10 +152,10 @@ class CallGraph(private val program: Program): IAstVisitor {
 
     override fun visit(jump: Jump) {
         val otherSub = jump.identifier?.targetSubroutine(program.namespace)
-        if(otherSub!=null) {
+        if (otherSub != null) {
             jump.definingSubroutine()?.let { thisSub ->
-                subroutinesCalling[thisSub] = subroutinesCalling.getValue(thisSub).plus(otherSub)
-                subroutinesCalledBy[otherSub] = subroutinesCalledBy.getValue(otherSub).plus(jump)
+                calls[thisSub] = calls.getValue(thisSub).plus(otherSub)
+                calledBy[otherSub] = calledBy.getValue(otherSub).plus(jump)
             }
         }
         super.visit(jump)
@@ -181,8 +174,6 @@ class CallGraph(private val program: Program): IAstVisitor {
     }
 
     private fun scanAssemblyCode(asm: String, context: Statement, scope: INameScope) {
-        val asmJumpRx = Regex("""[\-+a-zA-Z0-9_ \t]+(jmp|jsr)[ \t]+(\S+).*""", RegexOption.IGNORE_CASE)
-        val asmRefRx = Regex("""[\-+a-zA-Z0-9_ \t]+(...)[ \t]+(\S+).*""", RegexOption.IGNORE_CASE)
         asm.lines().forEach { line ->
             val matches = asmJumpRx.matchEntire(line)
             if (matches != null) {
@@ -190,27 +181,27 @@ class CallGraph(private val program: Program): IAstVisitor {
                 if (jumptarget != null && (jumptarget[0].isLetter() || jumptarget[0] == '_')) {
                     val node = program.namespace.lookup(jumptarget.split('.'), context)
                     if (node is Subroutine) {
-                        subroutinesCalling[scope] = subroutinesCalling.getValue(scope).plus(node)
-                        subroutinesCalledBy[node] = subroutinesCalledBy.getValue(node).plus(context)
-                    } else if(jumptarget.contains('.')) {
+                        calls[scope] = calls.getValue(scope).plus(node)
+                        calledBy[node] = calledBy.getValue(node).plus(context)
+                    } else if (jumptarget.contains('.')) {
                         // maybe only the first part already refers to a subroutine
                         val node2 = program.namespace.lookup(listOf(jumptarget.substringBefore('.')), context)
                         if (node2 is Subroutine) {
-                            subroutinesCalling[scope] = subroutinesCalling.getValue(scope).plus(node2)
-                            subroutinesCalledBy[node2] = subroutinesCalledBy.getValue(node2).plus(context)
+                            calls[scope] = calls.getValue(scope).plus(node2)
+                            calledBy[node2] = calledBy.getValue(node2).plus(context)
                         }
                     }
                 }
             } else {
                 val matches2 = asmRefRx.matchEntire(line)
                 if (matches2 != null) {
-                    val target= matches2.groups[2]?.value
+                    val target = matches2.groups[2]?.value
                     if (target != null && (target[0].isLetter() || target[0] == '_')) {
-                        if(target.contains('.')) {
+                        if (target.contains('.')) {
                             val node = program.namespace.lookup(listOf(target.substringBefore('.')), context)
                             if (node is Subroutine) {
-                                subroutinesCalling[scope] = subroutinesCalling.getValue(scope).plus(node)
-                                subroutinesCalledBy[node] = subroutinesCalledBy.getValue(node).plus(context)
+                                calls[scope] = calls.getValue(scope).plus(node)
+                                calledBy[node] = calledBy.getValue(node).plus(context)
                             }
                         }
                     }

compiler/src/prog8/optimizer/ConstExprEvaluator.kt

@@ -54,15 +54,15 @@ class ConstExprEvaluator {
 
     private fun logicalxor(left: NumericLiteralValue, right: NumericLiteralValue): NumericLiteralValue {
         val error = "cannot compute $left locical-bitxor $right"
-        return when {
-            left.type in IntegerDatatypes -> when {
-                right.type in IntegerDatatypes -> NumericLiteralValue.fromBoolean((left.number.toInt() != 0) xor (right.number.toInt() != 0), left.position)
-                right.type == DataType.FLOAT -> NumericLiteralValue.fromBoolean((left.number.toInt() != 0) xor (right.number.toDouble() != 0.0), left.position)
+        return when (left.type) {
+            in IntegerDatatypes -> when (right.type) {
+                in IntegerDatatypes -> NumericLiteralValue.fromBoolean((left.number.toInt() != 0) xor (right.number.toInt() != 0), left.position)
+                DataType.FLOAT -> NumericLiteralValue.fromBoolean((left.number.toInt() != 0) xor (right.number.toDouble() != 0.0), left.position)
                 else -> throw ExpressionError(error, left.position)
             }
-            left.type == DataType.FLOAT -> when {
-                right.type in IntegerDatatypes -> NumericLiteralValue.fromBoolean((left.number.toDouble() != 0.0) xor (right.number.toInt() != 0), left.position)
-                right.type == DataType.FLOAT -> NumericLiteralValue.fromBoolean((left.number.toDouble() != 0.0) xor (right.number.toDouble() != 0.0), left.position)
+            DataType.FLOAT -> when (right.type) {
+                in IntegerDatatypes -> NumericLiteralValue.fromBoolean((left.number.toDouble() != 0.0) xor (right.number.toInt() != 0), left.position)
+                DataType.FLOAT -> NumericLiteralValue.fromBoolean((left.number.toDouble() != 0.0) xor (right.number.toDouble() != 0.0), left.position)
                 else -> throw ExpressionError(error, left.position)
             }
             else -> throw ExpressionError(error, left.position)
@@ -71,15 +71,15 @@ class ConstExprEvaluator {
 
     private fun logicalor(left: NumericLiteralValue, right: NumericLiteralValue): NumericLiteralValue {
         val error = "cannot compute $left locical-or $right"
-        return when {
-            left.type in IntegerDatatypes -> when {
-                right.type in IntegerDatatypes -> NumericLiteralValue.fromBoolean(left.number.toInt() != 0 || right.number.toInt() != 0, left.position)
-                right.type == DataType.FLOAT -> NumericLiteralValue.fromBoolean(left.number.toInt() != 0 || right.number.toDouble() != 0.0, left.position)
+        return when (left.type) {
+            in IntegerDatatypes -> when (right.type) {
+                in IntegerDatatypes -> NumericLiteralValue.fromBoolean(left.number.toInt() != 0 || right.number.toInt() != 0, left.position)
+                DataType.FLOAT -> NumericLiteralValue.fromBoolean(left.number.toInt() != 0 || right.number.toDouble() != 0.0, left.position)
                 else -> throw ExpressionError(error, left.position)
             }
-            left.type == DataType.FLOAT -> when {
-                right.type in IntegerDatatypes -> NumericLiteralValue.fromBoolean(left.number.toDouble() != 0.0 || right.number.toInt() != 0, left.position)
-                right.type == DataType.FLOAT -> NumericLiteralValue.fromBoolean(left.number.toDouble() != 0.0 || right.number.toDouble() != 0.0, left.position)
+            DataType.FLOAT -> when (right.type) {
+                in IntegerDatatypes -> NumericLiteralValue.fromBoolean(left.number.toDouble() != 0.0 || right.number.toInt() != 0, left.position)
+                DataType.FLOAT -> NumericLiteralValue.fromBoolean(left.number.toDouble() != 0.0 || right.number.toDouble() != 0.0, left.position)
                 else -> throw ExpressionError(error, left.position)
             }
             else -> throw ExpressionError(error, left.position)
@@ -88,15 +88,15 @@ class ConstExprEvaluator {
 
     private fun logicaland(left: NumericLiteralValue, right: NumericLiteralValue): NumericLiteralValue {
         val error = "cannot compute $left locical-and $right"
-        return when {
-            left.type in IntegerDatatypes -> when {
-                right.type in IntegerDatatypes -> NumericLiteralValue.fromBoolean(left.number.toInt() != 0 && right.number.toInt() != 0, left.position)
-                right.type == DataType.FLOAT -> NumericLiteralValue.fromBoolean(left.number.toInt() != 0 && right.number.toDouble() != 0.0, left.position)
+        return when (left.type) {
+            in IntegerDatatypes -> when (right.type) {
+                in IntegerDatatypes -> NumericLiteralValue.fromBoolean(left.number.toInt() != 0 && right.number.toInt() != 0, left.position)
+                DataType.FLOAT -> NumericLiteralValue.fromBoolean(left.number.toInt() != 0 && right.number.toDouble() != 0.0, left.position)
                 else -> throw ExpressionError(error, left.position)
             }
-            left.type == DataType.FLOAT -> when {
-                right.type in IntegerDatatypes -> NumericLiteralValue.fromBoolean(left.number.toDouble() != 0.0 && right.number.toInt() != 0, left.position)
-                right.type == DataType.FLOAT -> NumericLiteralValue.fromBoolean(left.number.toDouble() != 0.0 && right.number.toDouble() != 0.0, left.position)
+            DataType.FLOAT -> when (right.type) {
+                in IntegerDatatypes -> NumericLiteralValue.fromBoolean(left.number.toDouble() != 0.0 && right.number.toInt() != 0, left.position)
+                DataType.FLOAT -> NumericLiteralValue.fromBoolean(left.number.toDouble() != 0.0 && right.number.toDouble() != 0.0, left.position)
                 else -> throw ExpressionError(error, left.position)
             }
             else -> throw ExpressionError(error, left.position)
@@ -144,15 +144,15 @@ class ConstExprEvaluator {
 
     private fun power(left: NumericLiteralValue, right: NumericLiteralValue): NumericLiteralValue {
         val error = "cannot calculate $left ** $right"
-        return when {
-            left.type in IntegerDatatypes -> when {
-                right.type in IntegerDatatypes -> NumericLiteralValue.optimalNumeric(left.number.toInt().toDouble().pow(right.number.toInt()), left.position)
-                right.type == DataType.FLOAT -> NumericLiteralValue(DataType.FLOAT, left.number.toInt().toDouble().pow(right.number.toDouble()), left.position)
+        return when (left.type) {
+            in IntegerDatatypes -> when (right.type) {
+                in IntegerDatatypes -> NumericLiteralValue.optimalNumeric(left.number.toInt().toDouble().pow(right.number.toInt()), left.position)
+                DataType.FLOAT -> NumericLiteralValue(DataType.FLOAT, left.number.toInt().toDouble().pow(right.number.toDouble()), left.position)
                 else -> throw ExpressionError(error, left.position)
             }
-            left.type == DataType.FLOAT -> when {
-                right.type in IntegerDatatypes -> NumericLiteralValue(DataType.FLOAT, left.number.toDouble().pow(right.number.toInt()), left.position)
-                right.type == DataType.FLOAT -> NumericLiteralValue(DataType.FLOAT, left.number.toDouble().pow(right.number.toDouble()), left.position)
+            DataType.FLOAT -> when (right.type) {
+                in IntegerDatatypes -> NumericLiteralValue(DataType.FLOAT, left.number.toDouble().pow(right.number.toInt()), left.position)
+                DataType.FLOAT -> NumericLiteralValue(DataType.FLOAT, left.number.toDouble().pow(right.number.toDouble()), left.position)
                 else -> throw ExpressionError(error, left.position)
             }
             else -> throw ExpressionError(error, left.position)
@@ -161,15 +161,15 @@ class ConstExprEvaluator {
 
     private fun plus(left: NumericLiteralValue, right: NumericLiteralValue): NumericLiteralValue {
         val error = "cannot add $left and $right"
-        return when {
-            left.type in IntegerDatatypes -> when {
-                right.type in IntegerDatatypes -> NumericLiteralValue.optimalNumeric(left.number.toInt() + right.number.toInt(), left.position)
-                right.type == DataType.FLOAT -> NumericLiteralValue(DataType.FLOAT, left.number.toInt() + right.number.toDouble(), left.position)
+        return when (left.type) {
+            in IntegerDatatypes -> when (right.type) {
+                in IntegerDatatypes -> NumericLiteralValue.optimalNumeric(left.number.toInt() + right.number.toInt(), left.position)
+                DataType.FLOAT -> NumericLiteralValue(DataType.FLOAT, left.number.toInt() + right.number.toDouble(), left.position)
                 else -> throw ExpressionError(error, left.position)
             }
-            left.type == DataType.FLOAT -> when {
-                right.type in IntegerDatatypes -> NumericLiteralValue(DataType.FLOAT, left.number.toDouble() + right.number.toInt(), left.position)
-                right.type == DataType.FLOAT -> NumericLiteralValue(DataType.FLOAT, left.number.toDouble() + right.number.toDouble(), left.position)
+            DataType.FLOAT -> when (right.type) {
+                in IntegerDatatypes -> NumericLiteralValue(DataType.FLOAT, left.number.toDouble() + right.number.toInt(), left.position)
+                DataType.FLOAT -> NumericLiteralValue(DataType.FLOAT, left.number.toDouble() + right.number.toDouble(), left.position)
                 else -> throw ExpressionError(error, left.position)
             }
             else -> throw ExpressionError(error, left.position)
@@ -178,15 +178,15 @@ class ConstExprEvaluator {
 
     private fun minus(left: NumericLiteralValue, right: NumericLiteralValue): NumericLiteralValue {
         val error = "cannot subtract $left and $right"
-        return when {
-            left.type in IntegerDatatypes -> when {
-                right.type in IntegerDatatypes -> NumericLiteralValue.optimalNumeric(left.number.toInt() - right.number.toInt(), left.position)
-                right.type == DataType.FLOAT -> NumericLiteralValue(DataType.FLOAT, left.number.toInt() - right.number.toDouble(), left.position)
+        return when (left.type) {
+            in IntegerDatatypes -> when (right.type) {
+                in IntegerDatatypes -> NumericLiteralValue.optimalNumeric(left.number.toInt() - right.number.toInt(), left.position)
+                DataType.FLOAT -> NumericLiteralValue(DataType.FLOAT, left.number.toInt() - right.number.toDouble(), left.position)
                 else -> throw ExpressionError(error, left.position)
             }
-            left.type == DataType.FLOAT -> when {
-                right.type in IntegerDatatypes -> NumericLiteralValue(DataType.FLOAT, left.number.toDouble() - right.number.toInt(), left.position)
-                right.type == DataType.FLOAT -> NumericLiteralValue(DataType.FLOAT, left.number.toDouble() - right.number.toDouble(), left.position)
+            DataType.FLOAT -> when (right.type) {
+                in IntegerDatatypes -> NumericLiteralValue(DataType.FLOAT, left.number.toDouble() - right.number.toInt(), left.position)
+                DataType.FLOAT -> NumericLiteralValue(DataType.FLOAT, left.number.toDouble() - right.number.toDouble(), left.position)
                 else -> throw ExpressionError(error, left.position)
             }
             else -> throw ExpressionError(error, left.position)
@@ -195,15 +195,15 @@ class ConstExprEvaluator {
 
     private fun multiply(left: NumericLiteralValue, right: NumericLiteralValue): NumericLiteralValue {
         val error = "cannot multiply ${left.type} and ${right.type}"
-        return when {
-            left.type in IntegerDatatypes -> when {
-                right.type in IntegerDatatypes -> NumericLiteralValue.optimalNumeric(left.number.toInt() * right.number.toInt(), left.position)
-                right.type == DataType.FLOAT -> NumericLiteralValue(DataType.FLOAT, left.number.toInt() * right.number.toDouble(), left.position)
+        return when (left.type) {
+            in IntegerDatatypes -> when (right.type) {
+                in IntegerDatatypes -> NumericLiteralValue.optimalNumeric(left.number.toInt() * right.number.toInt(), left.position)
+                DataType.FLOAT -> NumericLiteralValue(DataType.FLOAT, left.number.toInt() * right.number.toDouble(), left.position)
                 else -> throw ExpressionError(error, left.position)
             }
-            left.type == DataType.FLOAT -> when {
-                right.type in IntegerDatatypes -> NumericLiteralValue(DataType.FLOAT, left.number.toDouble() * right.number.toInt(), left.position)
-                right.type == DataType.FLOAT -> NumericLiteralValue(DataType.FLOAT, left.number.toDouble() * right.number.toDouble(), left.position)
+            DataType.FLOAT -> when (right.type) {
+                in IntegerDatatypes -> NumericLiteralValue(DataType.FLOAT, left.number.toDouble() * right.number.toInt(), left.position)
+                DataType.FLOAT -> NumericLiteralValue(DataType.FLOAT, left.number.toDouble() * right.number.toDouble(), left.position)
                 else -> throw ExpressionError(error, left.position)
             }
             else -> throw ExpressionError(error, left.position)
@@ -215,25 +215,25 @@ class ConstExprEvaluator {
 
     private fun divide(left: NumericLiteralValue, right: NumericLiteralValue): NumericLiteralValue {
         val error = "cannot divide $left by $right"
-        return when {
-            left.type in IntegerDatatypes -> when {
-                right.type in IntegerDatatypes -> {
+        return when (left.type) {
+            in IntegerDatatypes -> when (right.type) {
+                in IntegerDatatypes -> {
                     if(right.number.toInt()==0) divideByZeroError(right.position)
                     val result: Int = left.number.toInt() / right.number.toInt()
                     NumericLiteralValue.optimalNumeric(result, left.position)
                 }
-                right.type == DataType.FLOAT -> {
+                DataType.FLOAT -> {
                     if(right.number.toDouble()==0.0) divideByZeroError(right.position)
                     NumericLiteralValue(DataType.FLOAT, left.number.toInt() / right.number.toDouble(), left.position)
                 }
                 else -> throw ExpressionError(error, left.position)
             }
-            left.type == DataType.FLOAT -> when {
-                right.type in IntegerDatatypes -> {
+            DataType.FLOAT -> when (right.type) {
+                in IntegerDatatypes -> {
                     if(right.number.toInt()==0) divideByZeroError(right.position)
                     NumericLiteralValue(DataType.FLOAT, left.number.toDouble() / right.number.toInt(), left.position)
                 }
-                right.type == DataType.FLOAT -> {
+                DataType.FLOAT -> {
                     if(right.number.toDouble()==0.0) divideByZeroError(right.position)
                     NumericLiteralValue(DataType.FLOAT, left.number.toDouble() / right.number.toDouble(), left.position)
                 }
@@ -245,24 +245,24 @@ class ConstExprEvaluator {
 
     private fun remainder(left: NumericLiteralValue, right: NumericLiteralValue): NumericLiteralValue {
         val error = "cannot compute remainder of $left by $right"
-        return when {
-            left.type in IntegerDatatypes -> when {
-                right.type in IntegerDatatypes -> {
+        return when (left.type) {
+            in IntegerDatatypes -> when (right.type) {
+                in IntegerDatatypes -> {
                     if(right.number.toInt()==0) divideByZeroError(right.position)
                     NumericLiteralValue.optimalNumeric(left.number.toInt().toDouble() % right.number.toInt().toDouble(), left.position)
                 }
-                right.type == DataType.FLOAT -> {
+                DataType.FLOAT -> {
                     if(right.number.toDouble()==0.0) divideByZeroError(right.position)
                     NumericLiteralValue(DataType.FLOAT, left.number.toInt() % right.number.toDouble(), left.position)
                 }
                 else -> throw ExpressionError(error, left.position)
             }
-            left.type == DataType.FLOAT -> when {
-                right.type in IntegerDatatypes -> {
+            DataType.FLOAT -> when (right.type) {
+                in IntegerDatatypes -> {
                     if(right.number.toInt()==0) divideByZeroError(right.position)
                     NumericLiteralValue(DataType.FLOAT, left.number.toDouble() % right.number.toInt(), left.position)
                 }
-                right.type == DataType.FLOAT -> {
+                DataType.FLOAT -> {
                     if(right.number.toDouble()==0.0) divideByZeroError(right.position)
                     NumericLiteralValue(DataType.FLOAT, left.number.toDouble() % right.number.toDouble(), left.position)
                 }

compiler/src/prog8/optimizer/ConstantFolding.kt

@@ -1,678 +0,0 @@
-package prog8.optimizer
-
-import prog8.ast.IFunctionCall
-import prog8.ast.Program
-import prog8.ast.base.*
-import prog8.ast.expressions.*
-import prog8.ast.processing.IAstModifyingVisitor
-import prog8.ast.processing.fixupArrayDatatype
-import prog8.ast.statements.*
-import prog8.compiler.target.c64.MachineDefinition.FLOAT_MAX_NEGATIVE
-import prog8.compiler.target.c64.MachineDefinition.FLOAT_MAX_POSITIVE
-import prog8.functions.BuiltinFunctions
-import kotlin.math.floor
-
-
-class ConstantFolding(private val program: Program) : IAstModifyingVisitor {
-    var optimizationsDone: Int = 0
-    var errors : MutableList<AstException> = mutableListOf()
-    private val reportedErrorMessages = mutableSetOf<String>()
-
-    fun addError(x: AstException) {
-        // check that we don't add the isSameAs error more than once
-        if(x.toString() !in reportedErrorMessages) {
-            reportedErrorMessages.add(x.toString())
-            errors.add(x)
-        }
-    }
-
-    override fun visit(decl: VarDecl): Statement {
-        // the initializer value can't refer to the variable itself (recursive definition)
-        // TODO: use call tree for this?
-        if(decl.value?.referencesIdentifiers(decl.name) == true || decl.arraysize?.index?.referencesIdentifiers(decl.name) == true) {
-            errors.add(ExpressionError("recursive var declaration", decl.position))
-            return decl
-        }
-
-        if(decl.type==VarDeclType.CONST || decl.type==VarDeclType.VAR) {
-            if(decl.isArray){
-                if(decl.arraysize==null) {
-                    // for arrays that have no size specifier (or a non-constant one) attempt to deduce the size
-                    val arrayval = (decl.value as? ReferenceLiteralValue)?.array
-                    if(arrayval!=null) {
-                        decl.arraysize = ArrayIndex(NumericLiteralValue.optimalInteger(arrayval.size, decl.position), decl.position)
-                        optimizationsDone++
-                    }
-                }
-                else if(decl.arraysize?.size()==null) {
-                    val size = decl.arraysize!!.index.accept(this)
-                    if(size is NumericLiteralValue) {
-                        decl.arraysize = ArrayIndex(size, decl.position)
-                        optimizationsDone++
-                    }
-                }
-            }
-
-            when(decl.datatype) {
-                DataType.FLOAT -> {
-                    // vardecl: for scalar float vars, promote constant integer initialization values to floats
-                    val litval = decl.value as? NumericLiteralValue
-                    if (litval!=null && litval.type in IntegerDatatypes) {
-                        val newValue = NumericLiteralValue(DataType.FLOAT, litval.number.toDouble(), litval.position)
-                        decl.value = newValue
-                        optimizationsDone++
-                        return super.visit(decl)
-                    }
-                }
-                in StringDatatypes -> {
-                    // nothing to do for strings
-                }
-                DataType.STRUCT -> {
-                    // struct defintions don't have anything else in them
-                }
-                DataType.ARRAY_UB, DataType.ARRAY_B, DataType.ARRAY_UW, DataType.ARRAY_W -> {
-                    val numericLv = decl.value as? NumericLiteralValue
-                    val rangeExpr = decl.value as? RangeExpr
-                    if(rangeExpr!=null) {
-                        // convert the initializer range expression to an actual array
-                        val declArraySize = decl.arraysize?.size()
-                        if(declArraySize!=null && declArraySize!=rangeExpr.size())
-                            errors.add(ExpressionError("range expression size doesn't match declared array size", decl.value?.position!!))
-                        val constRange = rangeExpr.toConstantIntegerRange()
-                        if(constRange!=null) {
-                            val eltType = rangeExpr.inferType(program)!!
-                            if(eltType in ByteDatatypes) {
-                                decl.value = ReferenceLiteralValue(decl.datatype,
-                                        array = constRange.map { NumericLiteralValue(eltType, it.toShort(), decl.value!!.position) }
-                                                .toTypedArray(), position = decl.value!!.position)
-                            } else {
-                                decl.value = ReferenceLiteralValue(decl.datatype,
-                                        array = constRange.map { NumericLiteralValue(eltType, it, decl.value!!.position) }
-                                                .toTypedArray(), position = decl.value!!.position)
-                            }
-                            decl.value!!.linkParents(decl)
-                            optimizationsDone++
-                            return super.visit(decl)
-                        }
-                    }
-                    if(numericLv!=null && numericLv.type== DataType.FLOAT)
-                        errors.add(ExpressionError("arraysize requires only integers here", numericLv.position))
-                    val size = decl.arraysize?.size() ?: return decl
-                    if (rangeExpr==null && numericLv!=null) {
-                        // arraysize initializer is empty or a single int, and we know the size; create the arraysize.
-                        val fillvalue = numericLv.number.toInt()
-                        when(decl.datatype){
-                            DataType.ARRAY_UB -> {
-                                if(fillvalue !in 0..255)
-                                    errors.add(ExpressionError("ubyte value overflow", numericLv.position))
-                            }
-                            DataType.ARRAY_B -> {
-                                if(fillvalue !in -128..127)
-                                    errors.add(ExpressionError("byte value overflow", numericLv.position))
-                            }
-                            DataType.ARRAY_UW -> {
-                                if(fillvalue !in 0..65535)
-                                    errors.add(ExpressionError("uword value overflow", numericLv.position))
-                            }
-                            DataType.ARRAY_W -> {
-                                if(fillvalue !in -32768..32767)
-                                    errors.add(ExpressionError("word value overflow", numericLv.position))
-                            }
-                            else -> {}
-                        }
-                        // create the array itself, filled with the fillvalue.
-                        val array = Array(size) {fillvalue}.map { NumericLiteralValue.optimalInteger(it, numericLv.position) as Expression}.toTypedArray()
-                        val refValue = ReferenceLiteralValue(decl.datatype, array = array, position = numericLv.position)
-                        refValue.addToHeap(program.heap)
-                        decl.value = refValue
-                        refValue.parent=decl
-                        optimizationsDone++
-                        return super.visit(decl)
-                    }
-                }
-                DataType.ARRAY_F  -> {
-                    val size = decl.arraysize?.size() ?: return decl
-                    val litval = decl.value as? NumericLiteralValue
-                    if(litval==null) {
-                        // there's no initialization value, but the size is known, so we're ok.
-                        return super.visit(decl)
-                    } else {
-                        // arraysize initializer is a single int, and we know the size.
-                        val fillvalue = litval.number.toDouble()
-                        if (fillvalue < FLOAT_MAX_NEGATIVE || fillvalue > FLOAT_MAX_POSITIVE)
-                            errors.add(ExpressionError("float value overflow", litval.position))
-                        else {
-                            // create the array itself, filled with the fillvalue.
-                            val array = Array(size) {fillvalue}.map { NumericLiteralValue(DataType.FLOAT, it, litval.position) as Expression}.toTypedArray()
-                            val refValue = ReferenceLiteralValue(DataType.ARRAY_F, array = array, position = litval.position)
-                            refValue.addToHeap(program.heap)
-                            decl.value = refValue
-                            refValue.parent=decl
-                            optimizationsDone++
-                            return super.visit(decl)
-                        }
-                    }
-                }
-                else -> {
-                    // nothing to do for this type
-                }
-            }
-        }
-
-        return super.visit(decl)
-    }
-
-    /**
-     * replace identifiers that refer to const value, with the value itself (if it's a simple type)
-     */
-    override fun visit(identifier: IdentifierReference): Expression {
-        return try {
-            val cval = identifier.constValue(program) ?: return identifier
-            return when {
-                cval.type in NumericDatatypes -> {
-                    val copy = NumericLiteralValue(cval.type, cval.number, identifier.position)
-                    copy.parent = identifier.parent
-                    copy
-                }
-                cval.type in PassByReferenceDatatypes -> TODO("ref type $identifier")
-                else -> identifier
-            }
-        } catch (ax: AstException) {
-            addError(ax)
-            identifier
-        }
-    }
-
-    override fun visit(functionCall: FunctionCall): Expression {
-        return try {
-            super.visit(functionCall)
-            typeCastConstArguments(functionCall)
-            functionCall.constValue(program) ?: functionCall
-        } catch (ax: AstException) {
-            addError(ax)
-            functionCall
-        }
-    }
-
-    override fun visit(functionCallStatement: FunctionCallStatement): Statement {
-        super.visit(functionCallStatement)
-        typeCastConstArguments(functionCallStatement)
-        return functionCallStatement
-    }
-
-    private fun typeCastConstArguments(functionCall: IFunctionCall) {
-        if(functionCall.target.nameInSource.size==1) {
-            val builtinFunction = BuiltinFunctions[functionCall.target.nameInSource.single()]
-            if(builtinFunction!=null) {
-                // match the arguments of a builtin function signature.
-                for(arg in functionCall.arglist.withIndex().zip(builtinFunction.parameters)) {
-                    val possibleDts = arg.second.possibleDatatypes
-                    val argConst = arg.first.value.constValue(program)
-                    if(argConst!=null && argConst.type !in possibleDts) {
-                        val convertedValue = argConst.cast(possibleDts.first())
-                        if(convertedValue!=null) {
-                            functionCall.arglist[arg.first.index] = convertedValue
-                            optimizationsDone++
-                        }
-                    }
-                }
-                return
-            }
-        }
-        // match the arguments of a subroutine.
-        val subroutine = functionCall.target.targetSubroutine(program.namespace)
-        if(subroutine!=null) {
-            // if types differ, try to typecast constant arguments to the function call to the desired data type of the parameter
-            for(arg in functionCall.arglist.withIndex().zip(subroutine.parameters)) {
-                val expectedDt = arg.second.type
-                val argConst = arg.first.value.constValue(program)
-                if(argConst!=null && argConst.type!=expectedDt) {
-                    val convertedValue = argConst.cast(expectedDt)
-                    if(convertedValue!=null) {
-                        functionCall.arglist[arg.first.index] = convertedValue
-                        optimizationsDone++
-                    }
-                }
-            }
-        }
-    }
-
-    override fun visit(memread: DirectMemoryRead): Expression {
-        // @( &thing )  -->  thing
-        val addrOf = memread.addressExpression as? AddressOf
-        if(addrOf!=null)
-            return super.visit(addrOf.identifier)
-        return super.visit(memread)
-    }
-
-    /**
-     * Try to accept a unary prefix expression.
-     * Compile-time constant sub expressions will be evaluated on the spot.
-     * For instance, the expression for "- 4.5" will be optimized into the float literal -4.5
-     */
-    override fun visit(expr: PrefixExpression): Expression {
-        return try {
-            val prefixExpr=super.visit(expr)
-            if(prefixExpr !is PrefixExpression)
-                return prefixExpr
-
-            val subexpr = prefixExpr.expression
-            if (subexpr is NumericLiteralValue) {
-                // accept prefixed literal values (such as -3, not true)
-                return when {
-                    prefixExpr.operator == "+" -> subexpr
-                    prefixExpr.operator == "-" -> when {
-                        subexpr.type in IntegerDatatypes -> {
-                            optimizationsDone++
-                            NumericLiteralValue.optimalNumeric(-subexpr.number.toInt(), subexpr.position)
-                        }
-                        subexpr.type == DataType.FLOAT -> {
-                            optimizationsDone++
-                            NumericLiteralValue(DataType.FLOAT, -subexpr.number.toDouble(), subexpr.position)
-                        }
-                        else -> throw ExpressionError("can only take negative of int or float", subexpr.position)
-                    }
-                    prefixExpr.operator == "~" -> when {
-                        subexpr.type in IntegerDatatypes -> {
-                            optimizationsDone++
-                            NumericLiteralValue.optimalNumeric(subexpr.number.toInt().inv(), subexpr.position)
-                        }
-                        else -> throw ExpressionError("can only take bitwise inversion of int", subexpr.position)
-                    }
-                    prefixExpr.operator == "not" -> {
-                        optimizationsDone++
-                        NumericLiteralValue.fromBoolean(subexpr.number.toDouble() == 0.0, subexpr.position)
-                    }
-                    else -> throw ExpressionError(prefixExpr.operator, subexpr.position)
-                }
-            }
-            return prefixExpr
-        } catch (ax: AstException) {
-            addError(ax)
-            expr
-        }
-    }
-
-    /**
-     * Try to accept a binary expression.
-     * Compile-time constant sub expressions will be evaluated on the spot.
-     * For instance, "9 * (4 + 2)" will be optimized into the integer literal 54.
-     *
-     * More complex stuff: reordering to group constants:
-     * If one of our operands is a Constant,
-     *   and the other operand is a Binary expression,
-     *   and one of ITS operands is a Constant,
-     *   and ITS other operand is NOT a Constant,
-     *   ...it may be possible to rewrite the expression to group the two Constants together,
-     *      to allow them to be const-folded away.
-     *
-     *  examples include:
-     *        (X / c1) * c2  ->  X / (c2/c1)
-     *        (X + c1) - c2  ->  X + (c1-c2)
-     */
-    override fun visit(expr: BinaryExpression): Expression {
-        return try {
-            super.visit(expr)
-
-            if(expr.left is ReferenceLiteralValue || expr.right is ReferenceLiteralValue)
-                TODO("binexpr with reference litval")
-
-            val leftconst = expr.left.constValue(program)
-            val rightconst = expr.right.constValue(program)
-
-            val subExpr: BinaryExpression? = when {
-                leftconst!=null -> expr.right as? BinaryExpression
-                rightconst!=null -> expr.left as? BinaryExpression
-                else -> null
-            }
-            if(subExpr!=null) {
-                val subleftconst = subExpr.left.constValue(program)
-                val subrightconst = subExpr.right.constValue(program)
-                if ((subleftconst != null && subrightconst == null) || (subleftconst==null && subrightconst!=null)) {
-                    // try reordering.
-                    return groupTwoConstsTogether(expr, subExpr,
-                            leftconst != null, rightconst != null,
-                            subleftconst != null, subrightconst != null)
-                }
-            }
-
-            // const fold when both operands are a const
-            return when {
-                leftconst != null && rightconst != null -> {
-                    optimizationsDone++
-                    val evaluator = ConstExprEvaluator()
-                    evaluator.evaluate(leftconst, expr.operator, rightconst)
-                }
-
-                else -> expr
-            }
-        } catch (ax: AstException) {
-            addError(ax)
-            expr
-        }
-    }
-
-    private fun groupTwoConstsTogether(expr: BinaryExpression,
-                                       subExpr: BinaryExpression,
-                                       leftIsConst: Boolean,
-                                       rightIsConst: Boolean,
-                                       subleftIsConst: Boolean,
-                                       subrightIsConst: Boolean): Expression
-    {
-        // @todo this implements only a small set of possible reorderings for now
-        if(expr.operator==subExpr.operator) {
-            // both operators are the isSameAs.
-            // If + or *,  we can simply swap the const of expr and Var in subexpr.
-            if(expr.operator=="+" || expr.operator=="*") {
-                if(leftIsConst) {
-                    if(subleftIsConst)
-                        expr.left = subExpr.right.also { subExpr.right = expr.left }
-                    else
-                        expr.left = subExpr.left.also { subExpr.left = expr.left }
-                } else {
-                    if(subleftIsConst)
-                        expr.right = subExpr.right.also {subExpr.right = expr.right }
-                    else
-                        expr.right = subExpr.left.also { subExpr.left = expr.right }
-                }
-                optimizationsDone++
-                return expr
-            }
-
-            // If - or /,  we simetimes must reorder more, and flip operators (- -> +, / -> *)
-            if(expr.operator=="-" || expr.operator=="/") {
-                optimizationsDone++
-                if(leftIsConst) {
-                    return if(subleftIsConst) {
-                        val tmp = subExpr.right
-                        subExpr.right = subExpr.left
-                        subExpr.left = expr.left
-                        expr.left = tmp
-                        expr.operator = if(expr.operator=="-") "+" else "*"
-                        expr
-                    } else
-                        BinaryExpression(
-                                BinaryExpression(expr.left, if (expr.operator == "-") "+" else "*", subExpr.right, subExpr.position),
-                                expr.operator, subExpr.left, expr.position)
-                } else {
-                    return if(subleftIsConst) {
-                        expr.right = subExpr.right.also { subExpr.right = expr.right }
-                        expr
-                    } else
-                        BinaryExpression(
-                                subExpr.left, expr.operator,
-                                BinaryExpression(expr.right, if (expr.operator == "-") "+" else "*", subExpr.right, subExpr.position),
-                                expr.position)
-                }
-            }
-            return expr
-
-        }
-        else
-        {
-
-            if(expr.operator=="/" && subExpr.operator=="*") {
-                optimizationsDone++
-                if(leftIsConst) {
-                    return if(subleftIsConst) {
-                        // C1/(C2*V) -> (C1/C2)/V
-                        BinaryExpression(
-                                BinaryExpression(expr.left, "/", subExpr.left, subExpr.position),
-                                "/",
-                                subExpr.right, expr.position)
-                    } else {
-                        // C1/(V*C2) -> (C1/C2)/V
-                        BinaryExpression(
-                                BinaryExpression(expr.left, "/", subExpr.right, subExpr.position),
-                                "/",
-                                subExpr.left, expr.position)
-                    }
-                } else {
-                    return if(subleftIsConst) {
-                        // (C1*V)/C2 -> (C1/C2)*V
-                        BinaryExpression(
-                                BinaryExpression(subExpr.left, "/", expr.right, subExpr.position),
-                                "*",
-                                subExpr.right, expr.position)
-                    } else {
-                        // (V*C1)/C2 -> (C1/C2)*V
-                        BinaryExpression(
-                                BinaryExpression(subExpr.right, "/", expr.right, subExpr.position),
-                                "*",
-                                subExpr.left, expr.position)
-                    }
-                }
-            }
-            else if(expr.operator=="*" && subExpr.operator=="/") {
-                optimizationsDone++
-                if(leftIsConst) {
-                    return if(subleftIsConst) {
-                        // C1*(C2/V) -> (C1*C2)/V
-                        BinaryExpression(
-                                BinaryExpression(expr.left, "*", subExpr.left, subExpr.position),
-                                "/",
-                                subExpr.right, expr.position)
-                    } else {
-                        // C1*(V/C2) -> (C1/C2)*V
-                        BinaryExpression(
-                                BinaryExpression(expr.left, "/", subExpr.right, subExpr.position),
-                                "*",
-                                subExpr.left, expr.position)
-                    }
-                } else {
-                    return if(subleftIsConst) {
-                        // (C1/V)*C2 -> (C1*C2)/V
-                        BinaryExpression(
-                                BinaryExpression(subExpr.left, "*", expr.right, subExpr.position),
-                                "/",
-                                subExpr.right, expr.position)
-                    } else {
-                        // (V/C1)*C2 -> (C1/C2)*V
-                        BinaryExpression(
-                                BinaryExpression(expr.right, "/", subExpr.right, subExpr.position),
-                                "*",
-                                subExpr.left, expr.position)
-                    }
-                }
-            }
-            else if(expr.operator=="+" && subExpr.operator=="-") {
-                optimizationsDone++
-                if(leftIsConst){
-                    return if(subleftIsConst){
-                        // c1+(c2-v)  ->  (c1+c2)-v
-                        BinaryExpression(
-                                BinaryExpression(expr.left, "+", subExpr.left, subExpr.position),
-                                "-",
-                                subExpr.right, expr.position)
-                    } else {
-                        // c1+(v-c2)  ->  v+(c1-c2)
-                        BinaryExpression(
-                                BinaryExpression(expr.left, "-", subExpr.right, subExpr.position),
-                                "+",
-                                subExpr.left, expr.position)
-                    }
-                } else {
-                    return if(subleftIsConst) {
-                        // (c1-v)+c2  ->  (c1+c2)-v
-                        BinaryExpression(
-                                BinaryExpression(subExpr.left, "+", expr.right, subExpr.position),
-                                "-",
-                                subExpr.right, expr.position)
-                    } else {
-                        // (v-c1)+c2  ->  v+(c2-c1)
-                        BinaryExpression(
-                                BinaryExpression(expr.right, "-", subExpr.right, subExpr.position),
-                                "+",
-                                subExpr.left, expr.position)
-                    }
-                }
-            }
-            else if(expr.operator=="-" && subExpr.operator=="+") {
-                optimizationsDone++
-                if(leftIsConst) {
-                    return if(subleftIsConst) {
-                        // c1-(c2+v)  ->  (c1-c2)-v
-                        BinaryExpression(
-                                BinaryExpression(expr.left, "-", subExpr.left, subExpr.position),
-                                "-",
-                                subExpr.right, expr.position)
-                    } else {
-                        // c1-(v+c2)  ->  (c1-c2)-v
-                        BinaryExpression(
-                                BinaryExpression(expr.left, "-", subExpr.right, subExpr.position),
-                                "-",
-                                subExpr.left, expr.position)
-                    }
-                } else {
-                    return if(subleftIsConst) {
-                        // (c1+v)-c2  ->  v+(c1-c2)
-                        BinaryExpression(
-                                BinaryExpression(subExpr.left, "-", expr.right, subExpr.position),
-                                "+",
-                                subExpr.right, expr.position)
-                    } else {
-                        // (v+c1)-c2  ->  v+(c1-c2)
-                        BinaryExpression(
-                                BinaryExpression(subExpr.right, "-", expr.right, subExpr.position),
-                                "+",
-                                subExpr.left, expr.position)
-                    }
-                }
-            }
-
-            return expr
-        }
-    }
-
-    override fun visit(forLoop: ForLoop): Statement {
-
-        fun adjustRangeDt(rangeFrom: NumericLiteralValue, targetDt: DataType, rangeTo: NumericLiteralValue, stepLiteral: NumericLiteralValue?, range: RangeExpr): RangeExpr {
-            val newFrom = rangeFrom.cast(targetDt)
-            val newTo = rangeTo.cast(targetDt)
-            if (newFrom != null && newTo != null) {
-                val newStep: Expression =
-                        if (stepLiteral != null) (stepLiteral.cast(targetDt) ?: stepLiteral) else range.step
-                return RangeExpr(newFrom, newTo, newStep, range.position)
-            }
-            return range
-        }
-
-        // adjust the datatype of a range expression in for loops to the loop variable.
-        val resultStmt = super.visit(forLoop) as ForLoop
-        val iterableRange = resultStmt.iterable as? RangeExpr ?: return resultStmt
-        val rangeFrom = iterableRange.from as? NumericLiteralValue
-        val rangeTo = iterableRange.to as? NumericLiteralValue
-        if(rangeFrom==null || rangeTo==null) return resultStmt
-
-        val loopvar = resultStmt.loopVar?.targetVarDecl(program.namespace)
-        if(loopvar!=null) {
-            val stepLiteral = iterableRange.step as? NumericLiteralValue
-            when(loopvar.datatype) {
-                DataType.UBYTE -> {
-                    if(rangeFrom.type!= DataType.UBYTE) {
-                        // attempt to translate the iterable into ubyte values
-                        resultStmt.iterable = adjustRangeDt(rangeFrom, loopvar.datatype, rangeTo, stepLiteral, iterableRange)
-                    }
-                }
-                DataType.BYTE -> {
-                    if(rangeFrom.type!= DataType.BYTE) {
-                        // attempt to translate the iterable into byte values
-                        resultStmt.iterable = adjustRangeDt(rangeFrom, loopvar.datatype, rangeTo, stepLiteral, iterableRange)
-                    }
-                }
-                DataType.UWORD -> {
-                    if(rangeFrom.type!= DataType.UWORD) {
-                        // attempt to translate the iterable into uword values
-                        resultStmt.iterable = adjustRangeDt(rangeFrom, loopvar.datatype, rangeTo, stepLiteral, iterableRange)
-                    }
-                }
-                DataType.WORD -> {
-                    if(rangeFrom.type!= DataType.WORD) {
-                        // attempt to translate the iterable into word values
-                        resultStmt.iterable = adjustRangeDt(rangeFrom, loopvar.datatype, rangeTo, stepLiteral, iterableRange)
-                    }
-                }
-                else -> throw FatalAstException("invalid loopvar datatype $loopvar")
-            }
-        }
-        return resultStmt
-    }
-
-    override fun visit(refLiteral: ReferenceLiteralValue): Expression {
-        val litval = super.visit(refLiteral)
-        if(litval is ReferenceLiteralValue) {
-            if (litval.isArray) {
-                val vardecl = litval.parent as? VarDecl
-                if (vardecl!=null) {
-                    return fixupArrayDatatype(litval, vardecl, program.heap)
-                }
-            }
-        }
-        return litval
-    }
-
-    override fun visit(assignment: Assignment): Statement {
-        super.visit(assignment)
-        val lv = assignment.value as? NumericLiteralValue
-        if(lv!=null) {
-            // see if we can promote/convert a literal value to the required datatype
-            when(assignment.target.inferType(program, assignment)) {
-                DataType.UWORD -> {
-                    // we can convert to UWORD: any UBYTE, BYTE/WORD that are >=0, FLOAT that's an integer 0..65535,
-                    if(lv.type== DataType.UBYTE)
-                        assignment.value = NumericLiteralValue(DataType.UWORD, lv.number.toInt(), lv.position)
-                    else if(lv.type== DataType.BYTE && lv.number.toInt()>=0)
-                        assignment.value = NumericLiteralValue(DataType.UWORD, lv.number.toInt(), lv.position)
-                    else if(lv.type== DataType.WORD && lv.number.toInt()>=0)
-                        assignment.value = NumericLiteralValue(DataType.UWORD, lv.number.toInt(), lv.position)
-                    else if(lv.type== DataType.FLOAT) {
-                        val d = lv.number.toDouble()
-                        if(floor(d)==d && d>=0 && d<=65535)
-                            assignment.value = NumericLiteralValue(DataType.UWORD, floor(d).toInt(), lv.position)
-                    }
-                }
-                DataType.UBYTE -> {
-                    // we can convert to UBYTE: UWORD <=255, BYTE >=0, FLOAT that's an integer 0..255,
-                    if(lv.type== DataType.UWORD && lv.number.toInt() <= 255)
-                        assignment.value = NumericLiteralValue(DataType.UBYTE, lv.number.toShort(), lv.position)
-                    else if(lv.type== DataType.BYTE && lv.number.toInt() >=0)
-                        assignment.value = NumericLiteralValue(DataType.UBYTE, lv.number.toShort(), lv.position)
-                    else if(lv.type== DataType.FLOAT) {
-                        val d = lv.number.toDouble()
-                        if(floor(d)==d && d >=0 && d<=255)
-                            assignment.value = NumericLiteralValue(DataType.UBYTE, floor(d).toShort(), lv.position)
-                    }
-                }
-                DataType.BYTE -> {
-                    // we can convert to BYTE: UWORD/UBYTE <= 127, FLOAT that's an integer 0..127
-                    if(lv.type== DataType.UWORD && lv.number.toInt() <= 127)
-                        assignment.value = NumericLiteralValue(DataType.BYTE, lv.number.toShort(), lv.position)
-                    else if(lv.type== DataType.UBYTE && lv.number.toInt() <= 127)
-                        assignment.value = NumericLiteralValue(DataType.BYTE, lv.number.toShort(), lv.position)
-                    else if(lv.type== DataType.FLOAT) {
-                        val d = lv.number.toDouble()
-                        if(floor(d)==d && d>=0 && d<=127)
-                            assignment.value = NumericLiteralValue(DataType.BYTE, floor(d).toShort(), lv.position)
-                    }
-                }
-                DataType.WORD -> {
-                    // we can convert to WORD: any UBYTE/BYTE, UWORD <= 32767, FLOAT that's an integer -32768..32767,
-                    if(lv.type== DataType.UBYTE || lv.type== DataType.BYTE)
-                        assignment.value = NumericLiteralValue(DataType.WORD, lv.number.toInt(), lv.position)
-                    else if(lv.type== DataType.UWORD && lv.number.toInt() <= 32767)
-                        assignment.value = NumericLiteralValue(DataType.WORD, lv.number.toInt(), lv.position)
-                    else if(lv.type== DataType.FLOAT) {
-                        val d = lv.number.toDouble()
-                        if(floor(d)==d && d>=-32768 && d<=32767)
-                            assignment.value = NumericLiteralValue(DataType.BYTE, floor(d).toShort(), lv.position)
-                    }
-                }
-                DataType.FLOAT -> {
-                    assignment.value = NumericLiteralValue(DataType.FLOAT, lv.number.toDouble(), lv.position)
-                }
-                else -> {}
-            }
-        }
-        return assignment
-    }
-}

compiler/src/prog8/optimizer/ConstantFoldingOptimizer.kt

@@ -0,0 +1,592 @@
+package prog8.optimizer
+
+import prog8.ast.Node
+import prog8.ast.Program
+import prog8.ast.base.*
+import prog8.ast.expressions.*
+import prog8.ast.processing.AstWalker
+import prog8.ast.processing.IAstModification
+import prog8.ast.statements.*
+import prog8.compiler.target.CompilationTarget
+
+
+// First thing to do is replace all constant identifiers with their actual value,
+// and the array var initializer values and sizes.
+// This is needed because further constant optimizations depend on those.
+internal class ConstantIdentifierReplacer(private val program: Program, private val errors: ErrorReporter) : AstWalker() {
+    private val noModifications = emptyList<IAstModification>()
+
+    override fun after(identifier: IdentifierReference, parent: Node): Iterable<IAstModification> {
+        // replace identifiers that refer to const value, with the value itself
+        // if it's a simple type and if it's not a left hand side variable
+        if(identifier.parent is AssignTarget)
+            return noModifications
+        var forloop = identifier.parent as? ForLoop
+        if(forloop==null)
+            forloop = identifier.parent.parent as? ForLoop
+        if(forloop!=null && identifier===forloop.loopVar)
+            return noModifications
+
+        val cval = identifier.constValue(program) ?: return noModifications
+        return when (cval.type) {
+            in NumericDatatypes -> listOf(IAstModification.ReplaceNode(identifier, NumericLiteralValue(cval.type, cval.number, identifier.position), identifier.parent))
+            in PassByReferenceDatatypes -> throw FatalAstException("pass-by-reference type should not be considered a constant")
+            else -> noModifications
+        }
+    }
+
+    override fun before(decl: VarDecl, parent: Node): Iterable<IAstModification> {
+        // the initializer value can't refer to the variable itself (recursive definition)
+        // TODO: use call graph for this?
+        if(decl.value?.referencesIdentifiers(decl.name) == true || decl.arraysize?.index?.referencesIdentifiers(decl.name) == true) {
+            errors.err("recursive var declaration", decl.position)
+            return noModifications
+        }
+
+        if(decl.type==VarDeclType.CONST || decl.type==VarDeclType.VAR) {
+            if(decl.isArray){
+                if(decl.arraysize==null) {
+                    // for arrays that have no size specifier (or a non-constant one) attempt to deduce the size
+                    val arrayval = decl.value as? ArrayLiteralValue
+                    if(arrayval!=null) {
+                        return listOf(IAstModification.SetExpression(
+                                { decl.arraysize = ArrayIndex(it, decl.position) },
+                                NumericLiteralValue.optimalInteger(arrayval.value.size, decl.position),
+                                decl
+                        ))
+                    }
+                }
+                else if(decl.arraysize?.size()==null) {
+                    val size = decl.arraysize!!.index.constValue(program)
+                    if(size!=null) {
+                        return listOf(IAstModification.SetExpression(
+                                { decl.arraysize = ArrayIndex(it, decl.position) },
+                                size, decl
+                        ))
+                    }
+                }
+            }
+
+            when(decl.datatype) {
+                DataType.FLOAT -> {
+                    // vardecl: for scalar float vars, promote constant integer initialization values to floats
+                    val litval = decl.value as? NumericLiteralValue
+                    if (litval!=null && litval.type in IntegerDatatypes) {
+                        val newValue = NumericLiteralValue(DataType.FLOAT, litval.number.toDouble(), litval.position)
+                        return listOf(IAstModification.ReplaceNode(decl.value!!, newValue, decl))
+                    }
+                }
+                DataType.ARRAY_UB, DataType.ARRAY_B, DataType.ARRAY_UW, DataType.ARRAY_W -> {
+                    val numericLv = decl.value as? NumericLiteralValue
+                    val rangeExpr = decl.value as? RangeExpr
+                    if(rangeExpr!=null) {
+                        // convert the initializer range expression to an actual array
+                        val declArraySize = decl.arraysize?.size()
+                        if(declArraySize!=null && declArraySize!=rangeExpr.size())
+                            errors.err("range expression size doesn't match declared array size", decl.value?.position!!)
+                        val constRange = rangeExpr.toConstantIntegerRange()
+                        if(constRange!=null) {
+                            val eltType = rangeExpr.inferType(program).typeOrElse(DataType.UBYTE)
+                            val newValue = if(eltType in ByteDatatypes) {
+                                ArrayLiteralValue(InferredTypes.InferredType.known(decl.datatype),
+                                        constRange.map { NumericLiteralValue(eltType, it.toShort(), decl.value!!.position) }.toTypedArray(),
+                                        position = decl.value!!.position)
+                            } else {
+                                ArrayLiteralValue(InferredTypes.InferredType.known(decl.datatype),
+                                        constRange.map { NumericLiteralValue(eltType, it, decl.value!!.position) }.toTypedArray(),
+                                        position = decl.value!!.position)
+                            }
+                            return listOf(IAstModification.ReplaceNode(decl.value!!, newValue, decl))
+                        }
+                    }
+                    if(numericLv!=null && numericLv.type==DataType.FLOAT)
+                        errors.err("arraysize requires only integers here", numericLv.position)
+                    val size = decl.arraysize?.size() ?: return noModifications
+                    if (rangeExpr==null && numericLv!=null) {
+                        // arraysize initializer is empty or a single int, and we know the size; create the arraysize.
+                        val fillvalue = numericLv.number.toInt()
+                        when(decl.datatype){
+                            DataType.ARRAY_UB -> {
+                                if(fillvalue !in 0..255)
+                                    errors.err("ubyte value overflow", numericLv.position)
+                            }
+                            DataType.ARRAY_B -> {
+                                if(fillvalue !in -128..127)
+                                    errors.err("byte value overflow", numericLv.position)
+                            }
+                            DataType.ARRAY_UW -> {
+                                if(fillvalue !in 0..65535)
+                                    errors.err("uword value overflow", numericLv.position)
+                            }
+                            DataType.ARRAY_W -> {
+                                if(fillvalue !in -32768..32767)
+                                    errors.err("word value overflow", numericLv.position)
+                            }
+                            else -> {}
+                        }
+                        // create the array itself, filled with the fillvalue.
+                        val array = Array(size) {fillvalue}.map { NumericLiteralValue(ArrayElementTypes.getValue(decl.datatype), it, numericLv.position) as Expression}.toTypedArray()
+                        val refValue = ArrayLiteralValue(InferredTypes.InferredType.known(decl.datatype), array, position = numericLv.position)
+                        return listOf(IAstModification.ReplaceNode(decl.value!!, refValue, decl))
+                    }
+                }
+                DataType.ARRAY_F  -> {
+                    val size = decl.arraysize?.size() ?: return noModifications
+                    val litval = decl.value as? NumericLiteralValue
+                    val rangeExpr = decl.value as? RangeExpr
+                    if(rangeExpr!=null) {
+                        // convert the initializer range expression to an actual array of floats
+                        val declArraySize = decl.arraysize?.size()
+                        if(declArraySize!=null && declArraySize!=rangeExpr.size())
+                            errors.err("range expression size doesn't match declared array size", decl.value?.position!!)
+                        val constRange = rangeExpr.toConstantIntegerRange()
+                        if(constRange!=null) {
+                            val newValue = ArrayLiteralValue(InferredTypes.InferredType.known(DataType.ARRAY_F),
+                                        constRange.map { NumericLiteralValue(DataType.FLOAT, it.toDouble(), decl.value!!.position) }.toTypedArray(),
+                                        position = decl.value!!.position)
+                            return listOf(IAstModification.ReplaceNode(decl.value!!, newValue, decl))
+                        }
+                    }
+                    if(rangeExpr==null && litval!=null) {
+                        // arraysize initializer is a single int, and we know the size.
+                        val fillvalue = litval.number.toDouble()
+                        if (fillvalue < CompilationTarget.machine.FLOAT_MAX_NEGATIVE || fillvalue > CompilationTarget.machine.FLOAT_MAX_POSITIVE)
+                            errors.err("float value overflow", litval.position)
+                        else {
+                            // create the array itself, filled with the fillvalue.
+                            val array = Array(size) {fillvalue}.map { NumericLiteralValue(DataType.FLOAT, it, litval.position) as Expression}.toTypedArray()
+                            val refValue = ArrayLiteralValue(InferredTypes.InferredType.known(DataType.ARRAY_F), array, position = litval.position)
+                            return listOf(IAstModification.ReplaceNode(decl.value!!, refValue, decl))
+                        }
+                    }
+                }
+                else -> {
+                    // nothing to do for this type
+                    // this includes strings and structs
+                }
+            }
+        }
+
+        val declValue = decl.value
+        if(declValue!=null && decl.type==VarDeclType.VAR
+                && declValue is NumericLiteralValue && !declValue.inferType(program).istype(decl.datatype)) {
+            // cast the numeric literal to the appropriate datatype of the variable
+            return listOf(IAstModification.ReplaceNode(decl.value!!, declValue.cast(decl.datatype), decl))
+        }
+
+        return noModifications
+    }
+}
+
+
+internal class ConstantFoldingOptimizer(private val program: Program) : AstWalker() {
+    private val noModifications = emptyList<IAstModification>()
+
+    override fun before(memread: DirectMemoryRead, parent: Node): Iterable<IAstModification> {
+        // @( &thing )  -->  thing
+        val addrOf = memread.addressExpression as? AddressOf
+        return if(addrOf!=null)
+            listOf(IAstModification.ReplaceNode(memread, addrOf.identifier, parent))
+        else
+            noModifications
+    }
+
+    override fun after(expr: PrefixExpression, parent: Node): Iterable<IAstModification> {
+        // Try to turn a unary prefix expression into a single constant value.
+        // Compile-time constant sub expressions will be evaluated on the spot.
+        // For instance, the expression for "- 4.5" will be optimized into the float literal -4.5
+        val subexpr = expr.expression
+        if (subexpr is NumericLiteralValue) {
+            // accept prefixed literal values (such as -3, not true)
+            return when (expr.operator) {
+                "+" -> listOf(IAstModification.ReplaceNode(expr, subexpr, parent))
+                "-" -> when (subexpr.type) {
+                    in IntegerDatatypes -> {
+                        listOf(IAstModification.ReplaceNode(expr,
+                                NumericLiteralValue.optimalNumeric(-subexpr.number.toInt(), subexpr.position),
+                                parent))
+                    }
+                    DataType.FLOAT -> {
+                        listOf(IAstModification.ReplaceNode(expr,
+                                NumericLiteralValue(DataType.FLOAT, -subexpr.number.toDouble(), subexpr.position),
+                                parent))
+                    }
+                    else -> throw ExpressionError("can only take negative of int or float", subexpr.position)
+                }
+                "~" -> when (subexpr.type) {
+                    in IntegerDatatypes -> {
+                        listOf(IAstModification.ReplaceNode(expr,
+                                NumericLiteralValue.optimalNumeric(subexpr.number.toInt().inv(), subexpr.position),
+                                parent))
+                    }
+                    else -> throw ExpressionError("can only take bitwise inversion of int", subexpr.position)
+                }
+                "not" -> {
+                    listOf(IAstModification.ReplaceNode(expr,
+                            NumericLiteralValue.fromBoolean(subexpr.number.toDouble() == 0.0, subexpr.position),
+                            parent))
+                }
+                else -> throw ExpressionError(expr.operator, subexpr.position)
+            }
+        }
+        return noModifications
+    }
+
+    /**
+     * Try to constfold a binary expression.
+     * Compile-time constant sub expressions will be evaluated on the spot.
+     * For instance, "9 * (4 + 2)" will be optimized into the integer literal 54.
+     *
+     * More complex stuff: reordering to group constants:
+     * If one of our operands is a Constant,
+     *   and the other operand is a Binary expression,
+     *   and one of ITS operands is a Constant,
+     *   and ITS other operand is NOT a Constant,
+     *   ...it may be possible to rewrite the expression to group the two Constants together,
+     *      to allow them to be const-folded away.
+     *
+     *  examples include:
+     *        (X / c1) * c2  ->  X / (c2/c1)
+     *        (X + c1) - c2  ->  X + (c1-c2)
+     */
+    override fun after(expr: BinaryExpression, parent: Node): Iterable<IAstModification> {
+        val leftconst = expr.left.constValue(program)
+        val rightconst = expr.right.constValue(program)
+
+        val subExpr: BinaryExpression? = when {
+            leftconst!=null -> expr.right as? BinaryExpression
+            rightconst!=null -> expr.left as? BinaryExpression
+            else -> null
+        }
+        if(subExpr!=null) {
+            val subleftconst = subExpr.left.constValue(program)
+            val subrightconst = subExpr.right.constValue(program)
+            if ((subleftconst != null && subrightconst == null) || (subleftconst==null && subrightconst!=null)) {
+                // try reordering.
+                val change = groupTwoConstsTogether(expr, subExpr,
+                        leftconst != null, rightconst != null,
+                        subleftconst != null, subrightconst != null)
+                return change?.let { listOf(it) } ?: noModifications
+            }
+        }
+
+        // const fold when both operands are a const
+        if(leftconst != null && rightconst != null) {
+            val evaluator = ConstExprEvaluator()
+            return listOf(IAstModification.ReplaceNode(
+                    expr,
+                    evaluator.evaluate(leftconst, expr.operator, rightconst),
+                    parent
+            ))
+        }
+
+        return noModifications
+    }
+
+    override fun after(array: ArrayLiteralValue, parent: Node): Iterable<IAstModification> {
+        // because constant folding can result in arrays that are now suddenly capable
+        // of telling the type of all their elements (for instance, when they contained -2 which
+        // was a prefix expression earlier), we recalculate the array's datatype.
+        if(array.type.isKnown)
+            return noModifications
+
+        // if the array literalvalue is inside an array vardecl, take the type from that
+        // otherwise infer it from the elements of the array
+        val vardeclType = (array.parent as? VarDecl)?.datatype
+        if(vardeclType!=null) {
+            val newArray = array.cast(vardeclType)
+            if (newArray != null && newArray != array)
+                return listOf(IAstModification.ReplaceNode(array, newArray, parent))
+        } else {
+            val arrayDt = array.guessDatatype(program)
+            if (arrayDt.isKnown) {
+                val newArray = array.cast(arrayDt.typeOrElse(DataType.STRUCT))
+                if (newArray != null && newArray != array)
+                    return listOf(IAstModification.ReplaceNode(array, newArray, parent))
+            }
+        }
+
+        return noModifications
+    }
+
+    override fun after(functionCall: FunctionCall, parent: Node): Iterable<IAstModification> {
+        // the args of a fuction are constfolded via recursion already.
+        val constvalue = functionCall.constValue(program)
+        return if(constvalue!=null)
+            listOf(IAstModification.ReplaceNode(functionCall, constvalue, parent))
+        else
+            noModifications
+    }
+
+    override fun after(forLoop: ForLoop, parent: Node): Iterable<IAstModification> {
+        fun adjustRangeDt(rangeFrom: NumericLiteralValue, targetDt: DataType, rangeTo: NumericLiteralValue, stepLiteral: NumericLiteralValue?, range: RangeExpr): RangeExpr {
+            val newFrom: NumericLiteralValue
+            val newTo: NumericLiteralValue
+            try {
+                newFrom = rangeFrom.cast(targetDt)
+                newTo = rangeTo.cast(targetDt)
+            } catch (x: ExpressionError) {
+                return range
+            }
+            val newStep: Expression = try {
+                stepLiteral?.cast(targetDt)?: range.step
+            } catch(ee: ExpressionError) {
+                range.step
+            }
+            return RangeExpr(newFrom, newTo, newStep, range.position)
+        }
+
+        // adjust the datatype of a range expression in for loops to the loop variable.
+        val iterableRange = forLoop.iterable as? RangeExpr ?: return noModifications
+        val rangeFrom = iterableRange.from as? NumericLiteralValue
+        val rangeTo = iterableRange.to as? NumericLiteralValue
+        if(rangeFrom==null || rangeTo==null) return noModifications
+
+        val loopvar = forLoop.loopVar.targetVarDecl(program.namespace)!!
+        val stepLiteral = iterableRange.step as? NumericLiteralValue
+        when(loopvar.datatype) {
+            DataType.UBYTE -> {
+                if(rangeFrom.type!= DataType.UBYTE) {
+                    // attempt to translate the iterable into ubyte values
+                    val newIter = adjustRangeDt(rangeFrom, loopvar.datatype, rangeTo, stepLiteral, iterableRange)
+                    return listOf(IAstModification.ReplaceNode(forLoop.iterable, newIter, forLoop))
+                }
+            }
+            DataType.BYTE -> {
+                if(rangeFrom.type!= DataType.BYTE) {
+                    // attempt to translate the iterable into byte values
+                    val newIter = adjustRangeDt(rangeFrom, loopvar.datatype, rangeTo, stepLiteral, iterableRange)
+                    return listOf(IAstModification.ReplaceNode(forLoop.iterable, newIter, forLoop))
+                }
+            }
+            DataType.UWORD -> {
+                if(rangeFrom.type!= DataType.UWORD) {
+                    // attempt to translate the iterable into uword values
+                    val newIter = adjustRangeDt(rangeFrom, loopvar.datatype, rangeTo, stepLiteral, iterableRange)
+                    return listOf(IAstModification.ReplaceNode(forLoop.iterable, newIter, forLoop))
+                }
+            }
+            DataType.WORD -> {
+                if(rangeFrom.type!= DataType.WORD) {
+                    // attempt to translate the iterable into word values
+                    val newIter = adjustRangeDt(rangeFrom, loopvar.datatype, rangeTo, stepLiteral, iterableRange)
+                    return listOf(IAstModification.ReplaceNode(forLoop.iterable, newIter, forLoop))
+                }
+            }
+            else -> throw FatalAstException("invalid loopvar datatype $loopvar")
+        }
+
+        return noModifications
+    }
+
+    private class ShuffleOperands(val expr: BinaryExpression,
+                                  val exprOperator: String?,
+                                  val subExpr: BinaryExpression,
+                                  val newExprLeft: Expression?,
+                                  val newExprRight: Expression?,
+                                  val newSubexprLeft: Expression?,
+                                  val newSubexprRight: Expression?
+                                  ): IAstModification {
+        override fun perform() {
+            if(exprOperator!=null) expr.operator = exprOperator
+            if(newExprLeft!=null) expr.left = newExprLeft
+            if(newExprRight!=null) expr.right = newExprRight
+            if(newSubexprLeft!=null) subExpr.left = newSubexprLeft
+            if(newSubexprRight!=null) subExpr.right = newSubexprRight
+        }
+    }
+
+    private fun groupTwoConstsTogether(expr: BinaryExpression,
+                                       subExpr: BinaryExpression,
+                                       leftIsConst: Boolean,
+                                       rightIsConst: Boolean,
+                                       subleftIsConst: Boolean,
+                                       subrightIsConst: Boolean): IAstModification?
+    {
+        // todo: this implements only a small set of possible reorderings at this time
+        if(expr.operator==subExpr.operator) {
+            // both operators are the same.
+            // If + or *,  we can simply shuffle the const operands around to optimize.
+            if(expr.operator=="+" || expr.operator=="*") {
+                return if(leftIsConst) {
+                    if(subleftIsConst)
+                        ShuffleOperands(expr, null, subExpr, subExpr.right, null, null, expr.left)
+                    else
+                        ShuffleOperands(expr, null, subExpr, subExpr.left, null, expr.left, null)
+                } else {
+                    if(subleftIsConst)
+                        ShuffleOperands(expr, null, subExpr, null, subExpr.right, null, expr.right)
+                    else
+                        ShuffleOperands(expr, null, subExpr, null, subExpr.left, expr.right, null)
+                }
+            }
+
+            // If - or /,  we simetimes must reorder more, and flip operators (- -> +, / -> *)
+            if(expr.operator=="-" || expr.operator=="/") {
+                if(leftIsConst) {
+                    return if (subleftIsConst) {
+                        ShuffleOperands(expr, if (expr.operator == "-") "+" else "*", subExpr, subExpr.right, null, expr.left, subExpr.left)
+                    } else {
+                        IAstModification.ReplaceNode(expr,
+                                BinaryExpression(
+                                        BinaryExpression(expr.left, if (expr.operator == "-") "+" else "*", subExpr.right, subExpr.position),
+                                        expr.operator, subExpr.left, expr.position),
+                                expr.parent)
+                    }
+                } else {
+                    return if(subleftIsConst) {
+                        return ShuffleOperands(expr, null, subExpr, null, subExpr.right, null, expr.right)
+                    } else {
+                        IAstModification.ReplaceNode(expr,
+                                BinaryExpression(
+                                        subExpr.left, expr.operator,
+                                        BinaryExpression(expr.right, if (expr.operator == "-") "+" else "*", subExpr.right, subExpr.position),
+                                        expr.position),
+                                expr.parent)
+                    }
+                }
+            }
+            return null
+
+        }
+        else
+        {
+
+            if(expr.operator=="/" && subExpr.operator=="*") {
+                if(leftIsConst) {
+                    val change = if(subleftIsConst) {
+                        // C1/(C2*V) -> (C1/C2)/V
+                        BinaryExpression(
+                                BinaryExpression(expr.left, "/", subExpr.left, subExpr.position),
+                                "/",
+                                subExpr.right, expr.position)
+                    } else {
+                        // C1/(V*C2) -> (C1/C2)/V
+                        BinaryExpression(
+                                BinaryExpression(expr.left, "/", subExpr.right, subExpr.position),
+                                "/",
+                                subExpr.left, expr.position)
+                    }
+                    return IAstModification.ReplaceNode(expr, change, expr.parent)
+                } else {
+                    val change = if(subleftIsConst) {
+                        // (C1*V)/C2 -> (C1/C2)*V
+                        BinaryExpression(
+                                BinaryExpression(subExpr.left, "/", expr.right, subExpr.position),
+                                "*",
+                                subExpr.right, expr.position)
+                    } else {
+                        // (V*C1)/C2 -> (C1/C2)*V
+                        BinaryExpression(
+                                BinaryExpression(subExpr.right, "/", expr.right, subExpr.position),
+                                "*",
+                                subExpr.left, expr.position)
+                    }
+                    return IAstModification.ReplaceNode(expr, change, expr.parent)
+                }
+            }
+            else if(expr.operator=="*" && subExpr.operator=="/") {
+                if(leftIsConst) {
+                    val change = if(subleftIsConst) {
+                        // C1*(C2/V) -> (C1*C2)/V
+                        BinaryExpression(
+                                BinaryExpression(expr.left, "*", subExpr.left, subExpr.position),
+                                "/",
+                                subExpr.right, expr.position)
+                    } else {
+                        // C1*(V/C2) -> (C1/C2)*V
+                        BinaryExpression(
+                                BinaryExpression(expr.left, "/", subExpr.right, subExpr.position),
+                                "*",
+                                subExpr.left, expr.position)
+                    }
+                    return IAstModification.ReplaceNode(expr, change, expr.parent)
+                } else {
+                    val change = if(subleftIsConst) {
+                        // (C1/V)*C2 -> (C1*C2)/V
+                        BinaryExpression(
+                                BinaryExpression(subExpr.left, "*", expr.right, subExpr.position),
+                                "/",
+                                subExpr.right, expr.position)
+                    } else {
+                        // (V/C1)*C2 -> (C1/C2)*V
+                        BinaryExpression(
+                                BinaryExpression(expr.right, "/", subExpr.right, subExpr.position),
+                                "*",
+                                subExpr.left, expr.position)
+                    }
+                    return IAstModification.ReplaceNode(expr, change, expr.parent)
+                }
+            }
+            else if(expr.operator=="+" && subExpr.operator=="-") {
+                if(leftIsConst){
+                    val change = if(subleftIsConst){
+                        // c1+(c2-v)  ->  (c1+c2)-v
+                        BinaryExpression(
+                                BinaryExpression(expr.left, "+", subExpr.left, subExpr.position),
+                                "-",
+                                subExpr.right, expr.position)
+                    } else {
+                        // c1+(v-c2)  ->  v+(c1-c2)
+                        BinaryExpression(
+                                BinaryExpression(expr.left, "-", subExpr.right, subExpr.position),
+                                "+",
+                                subExpr.left, expr.position)
+                    }
+                    return IAstModification.ReplaceNode(expr, change, expr.parent)
+                } else {
+                    val change = if(subleftIsConst) {
+                        // (c1-v)+c2  ->  (c1+c2)-v
+                        BinaryExpression(
+                                BinaryExpression(subExpr.left, "+", expr.right, subExpr.position),
+                                "-",
+                                subExpr.right, expr.position)
+                    } else {
+                        // (v-c1)+c2  ->  v+(c2-c1)
+                        BinaryExpression(
+                                BinaryExpression(expr.right, "-", subExpr.right, subExpr.position),
+                                "+",
+                                subExpr.left, expr.position)
+                    }
+                    return IAstModification.ReplaceNode(expr, change, expr.parent)
+                }
+            }
+            else if(expr.operator=="-" && subExpr.operator=="+") {
+                if(leftIsConst) {
+                    val change = if(subleftIsConst) {
+                        // c1-(c2+v)  ->  (c1-c2)-v
+                        BinaryExpression(
+                                BinaryExpression(expr.left, "-", subExpr.left, subExpr.position),
+                                "-",
+                                subExpr.right, expr.position)
+                    } else {
+                        // c1-(v+c2)  ->  (c1-c2)-v
+                        BinaryExpression(
+                                BinaryExpression(expr.left, "-", subExpr.right, subExpr.position),
+                                "-",
+                                subExpr.left, expr.position)
+                    }
+                    return IAstModification.ReplaceNode(expr, change, expr.parent)
+                } else {
+                    val change = if(subleftIsConst) {
+                        // (c1+v)-c2  ->  v+(c1-c2)
+                        BinaryExpression(
+                                BinaryExpression(subExpr.left, "-", expr.right, subExpr.position),
+                                "+",
+                                subExpr.right, expr.position)
+                    } else {
+                        // (v+c1)-c2  ->  v+(c1-c2)
+                        BinaryExpression(
+                                BinaryExpression(subExpr.right, "-", expr.right, subExpr.position),
+                                "+",
+                                subExpr.left, expr.position)
+                    }
+                    return IAstModification.ReplaceNode(expr, change, expr.parent)
+                }
+            }
+
+            return null
+        }
+    }
+
+}

compiler/src/prog8/optimizer/ExpressionSimplifier.kt

@@ -0,0 +1,661 @@
+package prog8.optimizer
+
+import prog8.ast.Node
+import prog8.ast.Program
+import prog8.ast.base.*
+import prog8.ast.expressions.*
+import prog8.ast.processing.AstWalker
+import prog8.ast.processing.IAstModification
+import kotlin.math.abs
+import kotlin.math.log2
+import kotlin.math.pow
+
+/*
+    todo add more expression optimizations
+
+    Investigate what optimizations binaryen has, also see  https://egorbo.com/peephole-optimizations.html
+
+ */
+
+
+internal class ExpressionSimplifier(private val program: Program) : AstWalker() {
+    private val powersOfTwo = (1..16).map { (2.0).pow(it) }.toSet()
+    private val negativePowersOfTwo = powersOfTwo.map { -it }.toSet()
+    private val noModifications = emptyList<IAstModification>()
+
+    override fun after(typecast: TypecastExpression, parent: Node): Iterable<IAstModification> {
+        val mods = mutableListOf<IAstModification>()
+
+        // try to statically convert a literal value into one of the desired type
+        val literal = typecast.expression as? NumericLiteralValue
+        if (literal != null) {
+            val newLiteral = literal.cast(typecast.type)
+            if (newLiteral !== literal)
+                mods += IAstModification.ReplaceNode(typecast.expression, newLiteral, typecast)
+        }
+
+        // remove redundant nested typecasts:
+        // if the typecast casts a value to the same type, remove the cast.
+        // if the typecast contains another typecast, remove the inner typecast.
+        val subTypecast = typecast.expression as? TypecastExpression
+        if (subTypecast != null) {
+            mods += IAstModification.ReplaceNode(typecast.expression, subTypecast.expression, typecast)
+        } else {
+            if (typecast.expression.inferType(program).istype(typecast.type))
+                mods += IAstModification.ReplaceNode(typecast, typecast.expression, parent)
+        }
+
+        return mods
+    }
+
+    override fun before(expr: PrefixExpression, parent: Node): Iterable<IAstModification> {
+        if (expr.operator == "+") {
+            // +X --> X
+            return listOf(IAstModification.ReplaceNode(expr, expr.expression, parent))
+        } else if (expr.operator == "not") {
+            when(expr.expression) {
+                is PrefixExpression -> {
+                    // NOT(NOT(...)) -> ...
+                    val pe = expr.expression as PrefixExpression
+                    if(pe.operator == "not")
+                        return listOf(IAstModification.ReplaceNode(expr, pe.expression, parent))
+                }
+                is BinaryExpression -> {
+                    // NOT (xxxx)  ->   invert the xxxx
+                    val be = expr.expression as BinaryExpression
+                    val newExpr = when (be.operator) {
+                        "<" -> BinaryExpression(be.left, ">=", be.right, be.position)
+                        ">" -> BinaryExpression(be.left, "<=", be.right, be.position)
+                        "<=" -> BinaryExpression(be.left, ">", be.right, be.position)
+                        ">=" -> BinaryExpression(be.left, "<", be.right, be.position)
+                        "==" -> BinaryExpression(be.left, "!=", be.right, be.position)
+                        "!=" -> BinaryExpression(be.left, "==", be.right, be.position)
+                        else -> null
+                    }
+
+                    if (newExpr != null)
+                        return listOf(IAstModification.ReplaceNode(expr, newExpr, parent))
+                }
+                else -> return noModifications
+            }
+        }
+        return noModifications
+    }
+
+    override fun after(expr: BinaryExpression, parent: Node): Iterable<IAstModification> {
+        val leftVal = expr.left.constValue(program)
+        val rightVal = expr.right.constValue(program)
+
+        val leftIDt = expr.left.inferType(program)
+        val rightIDt = expr.right.inferType(program)
+        if (!leftIDt.isKnown || !rightIDt.isKnown)
+            throw FatalAstException("can't determine datatype of both expression operands $expr")
+
+        // ConstValue <associativeoperator> X -->  X <associativeoperator> ConstValue
+        if (leftVal != null && expr.operator in associativeOperators && rightVal == null)
+            return listOf(IAstModification.SwapOperands(expr))
+
+        // X + (-A)  -->  X - A
+        if (expr.operator == "+" && (expr.right as? PrefixExpression)?.operator == "-") {
+            return listOf(IAstModification.ReplaceNode(
+                    expr,
+                    BinaryExpression(expr.left, "-", (expr.right as PrefixExpression).expression, expr.position),
+                    parent
+            ))
+        }
+
+        // (-A) + X  -->  X - A
+        if (expr.operator == "+" && (expr.left as? PrefixExpression)?.operator == "-") {
+            return listOf(IAstModification.ReplaceNode(
+                    expr,
+                    BinaryExpression(expr.right, "-", (expr.left as PrefixExpression).expression, expr.position),
+                    parent
+            ))
+        }
+
+        // X - (-A)  -->  X + A
+        if (expr.operator == "-" && (expr.right as? PrefixExpression)?.operator == "-") {
+            return listOf(IAstModification.ReplaceNode(
+                    expr,
+                    BinaryExpression(expr.left, "+", (expr.right as PrefixExpression).expression, expr.position),
+                    parent
+            ))
+        }
+
+        val leftDt = leftIDt.typeOrElse(DataType.STRUCT)
+        val rightDt = rightIDt.typeOrElse(DataType.STRUCT)
+
+        if (expr.operator == "+" || expr.operator == "-"
+                && leftVal == null && rightVal == null
+                && leftDt in NumericDatatypes && rightDt in NumericDatatypes) {
+            val leftBinExpr = expr.left as? BinaryExpression
+            val rightBinExpr = expr.right as? BinaryExpression
+            if (leftBinExpr?.operator == "*") {
+                if (expr.operator == "+") {
+                    // Y*X + X  ->  X*(Y + 1)
+                    // X*Y + X  ->  X*(Y + 1)
+                    val x = expr.right
+                    val y = determineY(x, leftBinExpr)
+                    if (y != null) {
+                        val yPlus1 = BinaryExpression(y, "+", NumericLiteralValue(leftDt, 1, y.position), y.position)
+                        val newExpr = BinaryExpression(x, "*", yPlus1, x.position)
+                        return listOf(IAstModification.ReplaceNode(expr, newExpr, parent))
+                    }
+                } else {
+                    // Y*X - X  ->  X*(Y - 1)
+                    // X*Y - X  ->  X*(Y - 1)
+                    val x = expr.right
+                    val y = determineY(x, leftBinExpr)
+                    if (y != null) {
+                        val yMinus1 = BinaryExpression(y, "-", NumericLiteralValue(leftDt, 1, y.position), y.position)
+                        val newExpr = BinaryExpression(x, "*", yMinus1, x.position)
+                        return listOf(IAstModification.ReplaceNode(expr, newExpr, parent))
+                    }
+                }
+            } else if (rightBinExpr?.operator == "*") {
+                if (expr.operator == "+") {
+                    // X + Y*X  ->  X*(Y + 1)
+                    // X + X*Y  ->  X*(Y + 1)
+                    val x = expr.left
+                    val y = determineY(x, rightBinExpr)
+                    if (y != null) {
+                        val yPlus1 = BinaryExpression(y, "+", NumericLiteralValue.optimalInteger(1, y.position), y.position)
+                        val newExpr = BinaryExpression(x, "*", yPlus1, x.position)
+                        return listOf(IAstModification.ReplaceNode(expr, newExpr, parent))
+                    }
+                }
+            }
+        }
+
+        if(expr.operator == ">=" && rightVal?.number == 0) {
+            if (leftDt == DataType.UBYTE || leftDt == DataType.UWORD) {
+                // unsigned >= 0 --> true
+                return listOf(IAstModification.ReplaceNode(expr, NumericLiteralValue.fromBoolean(true, expr.position), parent))
+            }
+            when(leftDt) {
+                DataType.BYTE -> {
+                    // signed >=0   --> signed ^ $80
+                    return listOf(IAstModification.ReplaceNode(
+                            expr,
+                            BinaryExpression(expr.left, "^", NumericLiteralValue.optimalInteger(0x80, expr.position), expr.position),
+                            parent
+                    ))
+                }
+                DataType.WORD -> {
+                    // signedw >=0   --> msb(signedw) ^ $80
+                    return listOf(IAstModification.ReplaceNode(
+                            expr,
+                            BinaryExpression(FunctionCall(IdentifierReference(listOf("msb"), expr.position),
+                                    mutableListOf(expr.left),
+                                    expr.position
+                            ), "^", NumericLiteralValue.optimalInteger(0x80, expr.position), expr.position),
+                            parent
+                    ))
+                }
+                else -> {}
+            }
+        }
+
+        if(expr.operator == "<" && rightVal?.number == 0) {
+            if (leftDt == DataType.UBYTE || leftDt == DataType.UWORD) {
+                // unsigned < 0 --> false
+                return listOf(IAstModification.ReplaceNode(expr, NumericLiteralValue.fromBoolean(false, expr.position), parent))
+            }
+            when(leftDt) {
+                DataType.BYTE -> {
+                    // signed < 0  -->  signed & $80
+                    return listOf(IAstModification.ReplaceNode(
+                            expr,
+                            BinaryExpression(expr.left, "&", NumericLiteralValue.optimalInteger(0x80, expr.position), expr.position),
+                            parent
+                    ))
+                }
+                DataType.WORD -> {
+                    // signedw < 0 -->  msb(signedw) & $80
+                    return listOf(IAstModification.ReplaceNode(
+                            expr,
+                            BinaryExpression(FunctionCall(IdentifierReference(listOf("msb"), expr.position),
+                                    mutableListOf(expr.left),
+                                    expr.position
+                            ), "&", NumericLiteralValue.optimalInteger(0x80, expr.position), expr.position),
+                            parent
+                    ))
+                }
+                else -> {}
+            }
+        }
+
+        // simplify when a term is constant and directly determines the outcome
+        val constTrue = NumericLiteralValue.fromBoolean(true, expr.position)
+        val constFalse = NumericLiteralValue.fromBoolean(false, expr.position)
+        val newExpr: Expression? = when (expr.operator) {
+            "or" -> {
+                if ((leftVal != null && leftVal.asBooleanValue) || (rightVal != null && rightVal.asBooleanValue))
+                    constTrue
+                else if (leftVal != null && !leftVal.asBooleanValue)
+                    expr.right
+                else if (rightVal != null && !rightVal.asBooleanValue)
+                    expr.left
+                else
+                    null
+            }
+            "and" -> {
+                if ((leftVal != null && !leftVal.asBooleanValue) || (rightVal != null && !rightVal.asBooleanValue))
+                    constFalse
+                else if (leftVal != null && leftVal.asBooleanValue)
+                    expr.right
+                else if (rightVal != null && rightVal.asBooleanValue)
+                    expr.left
+                else
+                    null
+            }
+            "xor" -> {
+                if (leftVal != null && !leftVal.asBooleanValue)
+                    expr.right
+                else if (rightVal != null && !rightVal.asBooleanValue)
+                    expr.left
+                else if (leftVal != null && leftVal.asBooleanValue)
+                    PrefixExpression("not", expr.right, expr.right.position)
+                else if (rightVal != null && rightVal.asBooleanValue)
+                    PrefixExpression("not", expr.left, expr.left.position)
+                else
+                    null
+            }
+            "|", "^" -> {
+                if (leftVal != null && !leftVal.asBooleanValue)
+                    expr.right
+                else if (rightVal != null && !rightVal.asBooleanValue)
+                    expr.left
+                else
+                    null
+            }
+            "&" -> {
+                if (leftVal != null && !leftVal.asBooleanValue)
+                    constFalse
+                else if (rightVal != null && !rightVal.asBooleanValue)
+                    constFalse
+                else
+                    null
+            }
+            "*" -> optimizeMultiplication(expr, leftVal, rightVal)
+            "/" -> optimizeDivision(expr, leftVal, rightVal)
+            "+" -> optimizeAdd(expr, leftVal, rightVal)
+            "-" -> optimizeSub(expr, leftVal, rightVal)
+            "**" -> optimizePower(expr, leftVal, rightVal)
+            "%" -> optimizeRemainder(expr, leftVal, rightVal)
+            ">>" -> optimizeShiftRight(expr, rightVal)
+            "<<" -> optimizeShiftLeft(expr, rightVal)
+            else -> null
+        }
+
+        if(newExpr != null)
+            return listOf(IAstModification.ReplaceNode(expr, newExpr, parent))
+
+        return noModifications
+    }
+
+    private fun determineY(x: Expression, subBinExpr: BinaryExpression): Expression? {
+        return when {
+            subBinExpr.left isSameAs x -> subBinExpr.right
+            subBinExpr.right isSameAs x -> subBinExpr.left
+            else -> null
+        }
+    }
+
+    private fun optimizeAdd(expr: BinaryExpression, leftVal: NumericLiteralValue?, rightVal: NumericLiteralValue?): Expression? {
+        if(expr.left.isSameAs(expr.right)) {
+            // optimize X+X into X *2
+            expr.operator = "*"
+            expr.right = NumericLiteralValue.optimalInteger(2, expr.right.position)
+            expr.right.linkParents(expr)
+            return expr
+        }
+
+        if (leftVal == null && rightVal == null)
+            return null
+
+        val (expr2, _, rightVal2) = reorderAssociative(expr, leftVal)
+        if (rightVal2 != null) {
+            // right value is a constant, see if we can optimize
+            val rightConst: NumericLiteralValue = rightVal2
+            when (rightConst.number.toDouble()) {
+                0.0 -> {
+                    // left
+                    return expr2.left
+                }
+            }
+        }
+        // no need to check for left val constant (because of associativity)
+
+        return null
+    }
+
+    private fun optimizeSub(expr: BinaryExpression, leftVal: NumericLiteralValue?, rightVal: NumericLiteralValue?): Expression? {
+        if(expr.left.isSameAs(expr.right)) {
+            // optimize X-X into 0
+            return NumericLiteralValue.optimalInteger(0, expr.position)
+        }
+
+        if (leftVal == null && rightVal == null)
+            return null
+
+        if (rightVal != null) {
+            // right value is a constant, see if we can optimize
+            val rightConst: NumericLiteralValue = rightVal
+            when (rightConst.number.toDouble()) {
+                0.0 -> {
+                    // left
+                    return expr.left
+                }
+            }
+        }
+        if (leftVal != null) {
+            // left value is a constant, see if we can optimize
+            when (leftVal.number.toDouble()) {
+                0.0 -> {
+                    // -right
+                    return PrefixExpression("-", expr.right, expr.position)
+                }
+            }
+        }
+
+        return null
+    }
+
+    private fun optimizePower(expr: BinaryExpression, leftVal: NumericLiteralValue?, rightVal: NumericLiteralValue?): Expression? {
+        if (leftVal == null && rightVal == null)
+            return null
+
+        if (rightVal != null) {
+            // right value is a constant, see if we can optimize
+            val rightConst: NumericLiteralValue = rightVal
+            when (rightConst.number.toDouble()) {
+                -3.0 -> {
+                    // -1/(left*left*left)
+                    return BinaryExpression(NumericLiteralValue(DataType.FLOAT, -1.0, expr.position), "/",
+                            BinaryExpression(expr.left, "*", BinaryExpression(expr.left, "*", expr.left, expr.position), expr.position),
+                            expr.position)
+                }
+                -2.0 -> {
+                    // -1/(left*left)
+                    return BinaryExpression(NumericLiteralValue(DataType.FLOAT, -1.0, expr.position), "/",
+                            BinaryExpression(expr.left, "*", expr.left, expr.position),
+                            expr.position)
+                }
+                -1.0 -> {
+                    // -1/left
+                    return BinaryExpression(NumericLiteralValue(DataType.FLOAT, -1.0, expr.position), "/",
+                            expr.left, expr.position)
+                }
+                0.0 -> {
+                    // 1
+                    return NumericLiteralValue(rightConst.type, 1, expr.position)
+                }
+                0.5 -> {
+                    // sqrt(left)
+                    return FunctionCall(IdentifierReference(listOf("sqrt"), expr.position), mutableListOf(expr.left), expr.position)
+                }
+                1.0 -> {
+                    // left
+                    return expr.left
+                }
+                2.0 -> {
+                    // left*left
+                    return BinaryExpression(expr.left, "*", expr.left, expr.position)
+                }
+                3.0 -> {
+                    // left*left*left
+                    return BinaryExpression(expr.left, "*", BinaryExpression(expr.left, "*", expr.left, expr.position), expr.position)
+                }
+            }
+        }
+        if (leftVal != null) {
+            // left value is a constant, see if we can optimize
+            when (leftVal.number.toDouble()) {
+                -1.0 -> {
+                    // -1
+                    return NumericLiteralValue(DataType.FLOAT, -1.0, expr.position)
+                }
+                0.0 -> {
+                    // 0
+                    return NumericLiteralValue(leftVal.type, 0, expr.position)
+                }
+                1.0 -> {
+                    //1
+                    return NumericLiteralValue(leftVal.type, 1, expr.position)
+                }
+
+            }
+        }
+
+        return null
+    }
+
+    private fun optimizeRemainder(expr: BinaryExpression, leftVal: NumericLiteralValue?, rightVal: NumericLiteralValue?): Expression? {
+        if (leftVal == null && rightVal == null)
+            return null
+
+        // simplify assignments  A = B <operator> C
+
+        val cv = rightVal?.number?.toInt()?.toDouble()
+        when (expr.operator) {
+            "%" -> {
+                if (cv == 1.0) {
+                    return NumericLiteralValue(expr.inferType(program).typeOrElse(DataType.STRUCT), 0, expr.position)
+                } else if (cv == 2.0) {
+                    expr.operator = "&"
+                    expr.right = NumericLiteralValue.optimalInteger(1, expr.position)
+                    return null
+                }
+            }
+        }
+        return null
+
+    }
+
+    private fun optimizeDivision(expr: BinaryExpression, leftVal: NumericLiteralValue?, rightVal: NumericLiteralValue?): Expression? {
+        if (leftVal == null && rightVal == null)
+            return null
+
+        // cannot shuffle assiciativity with division!
+        if (rightVal != null) {
+            // right value is a constant, see if we can optimize
+            val rightConst: NumericLiteralValue = rightVal
+            val cv = rightConst.number.toDouble()
+            val leftIDt = expr.left.inferType(program)
+            if (!leftIDt.isKnown)
+                return null
+            val leftDt = leftIDt.typeOrElse(DataType.STRUCT)
+            when (cv) {
+                -1.0 -> {
+                    //  '/' -> -left
+                    if (expr.operator == "/") {
+                        return PrefixExpression("-", expr.left, expr.position)
+                    }
+                }
+                1.0 -> {
+                    //  '/' -> left
+                    if (expr.operator == "/") {
+                        return expr.left
+                    }
+                }
+                in powersOfTwo -> {
+                    if (leftDt in IntegerDatatypes) {
+                        // divided by a power of two => shift right
+                        val numshifts = log2(cv).toInt()
+                        return BinaryExpression(expr.left, ">>", NumericLiteralValue.optimalInteger(numshifts, expr.position), expr.position)
+                    }
+                }
+                in negativePowersOfTwo -> {
+                    if (leftDt in IntegerDatatypes) {
+                        // divided by a negative power of two => negate, then shift right
+                        val numshifts = log2(-cv).toInt()
+                        return BinaryExpression(PrefixExpression("-", expr.left, expr.position), ">>", NumericLiteralValue.optimalInteger(numshifts, expr.position), expr.position)
+                    }
+                }
+            }
+
+            if (leftDt == DataType.UBYTE) {
+                if (abs(rightConst.number.toDouble()) >= 256.0) {
+                    return NumericLiteralValue(DataType.UBYTE, 0, expr.position)
+                }
+            } else if (leftDt == DataType.UWORD) {
+                if (abs(rightConst.number.toDouble()) >= 65536.0) {
+                    return NumericLiteralValue(DataType.UBYTE, 0, expr.position)
+                }
+            }
+        }
+
+        if (leftVal != null) {
+            // left value is a constant, see if we can optimize
+            when (leftVal.number.toDouble()) {
+                0.0 -> {
+                    // 0
+                    return NumericLiteralValue(leftVal.type, 0, expr.position)
+                }
+            }
+        }
+
+        return null
+    }
+
+    private fun optimizeMultiplication(expr: BinaryExpression, leftVal: NumericLiteralValue?, rightVal: NumericLiteralValue?): Expression? {
+        if (leftVal == null && rightVal == null)
+            return null
+
+        val (expr2, _, rightVal2) = reorderAssociative(expr, leftVal)
+        if (rightVal2 != null) {
+            // right value is a constant, see if we can optimize
+            val leftValue: Expression = expr2.left
+            val rightConst: NumericLiteralValue = rightVal2
+            when (val cv = rightConst.number.toDouble()) {
+                -1.0 -> {
+                    // -left
+                    return PrefixExpression("-", leftValue, expr.position)
+                }
+                0.0 -> {
+                    // 0
+                    return NumericLiteralValue(rightConst.type, 0, expr.position)
+                }
+                1.0 -> {
+                    // left
+                    return expr2.left
+                }
+                in powersOfTwo -> {
+                    if (leftValue.inferType(program).typeOrElse(DataType.STRUCT) in IntegerDatatypes) {
+                        // times a power of two => shift left
+                        val numshifts = log2(cv).toInt()
+                        return BinaryExpression(expr2.left, "<<", NumericLiteralValue.optimalInteger(numshifts, expr.position), expr.position)
+                    }
+                }
+                in negativePowersOfTwo -> {
+                    if (leftValue.inferType(program).typeOrElse(DataType.STRUCT) in IntegerDatatypes) {
+                        // times a negative power of two => negate, then shift left
+                        val numshifts = log2(-cv).toInt()
+                        return BinaryExpression(PrefixExpression("-", expr2.left, expr.position), "<<", NumericLiteralValue.optimalInteger(numshifts, expr.position), expr.position)
+                    }
+                }
+            }
+        }
+        // no need to check for left val constant (because of associativity)
+
+        return null
+    }
+
+    private fun optimizeShiftLeft(expr: BinaryExpression, amountLv: NumericLiteralValue?): Expression? {
+        if (amountLv == null)
+            return null
+
+        val amount = amountLv.number.toInt()
+        if (amount == 0) {
+            return expr.left
+        }
+        val targetDt = expr.left.inferType(program).typeOrElse(DataType.STRUCT)
+        when (targetDt) {
+            DataType.UBYTE, DataType.BYTE -> {
+                if (amount >= 8) {
+                    return NumericLiteralValue(targetDt, 0, expr.position)
+                }
+            }
+            DataType.UWORD, DataType.WORD -> {
+                if (amount >= 16) {
+                    return NumericLiteralValue(targetDt, 0, expr.position)
+                } else if (amount >= 8) {
+                    val lsb = TypecastExpression(expr.left, DataType.UBYTE, true, expr.position)
+                    if (amount == 8) {
+                        return FunctionCall(IdentifierReference(listOf("mkword"), expr.position), mutableListOf(NumericLiteralValue.optimalInteger(0, expr.position), lsb), expr.position)
+                    }
+                    val shifted = BinaryExpression(lsb, "<<", NumericLiteralValue.optimalInteger(amount - 8, expr.position), expr.position)
+                    return FunctionCall(IdentifierReference(listOf("mkword"), expr.position), mutableListOf(NumericLiteralValue.optimalInteger(0, expr.position), shifted), expr.position)
+                }
+            }
+            else -> {
+            }
+        }
+        return null
+    }
+
+    private fun optimizeShiftRight(expr: BinaryExpression, amountLv: NumericLiteralValue?): Expression? {
+        if (amountLv == null)
+            return null
+
+        val amount = amountLv.number.toInt()
+        if (amount == 0) {
+            return expr.left
+        }
+        when (expr.left.inferType(program).typeOrElse(DataType.STRUCT)) {
+            DataType.UBYTE -> {
+                if (amount >= 8) {
+                    return NumericLiteralValue.optimalInteger(0, expr.position)
+                }
+            }
+            DataType.BYTE -> {
+                if (amount > 8) {
+                    expr.right = NumericLiteralValue.optimalInteger(8, expr.right.position)
+                    return null
+                }
+            }
+            DataType.UWORD -> {
+                if (amount >= 16) {
+                    return NumericLiteralValue.optimalInteger(0, expr.position)
+                } else if (amount >= 8) {
+                    val msb = FunctionCall(IdentifierReference(listOf("msb"), expr.position), mutableListOf(expr.left), expr.position)
+                    if (amount == 8)
+                        return msb
+                    return BinaryExpression(msb, ">>", NumericLiteralValue.optimalInteger(amount - 8, expr.position), expr.position)
+                }
+            }
+            DataType.WORD -> {
+                if (amount > 16) {
+                    expr.right = NumericLiteralValue.optimalInteger(16, expr.right.position)
+                    return null
+                } else if (amount >= 8) {
+                    val msbAsByte = TypecastExpression(
+                            FunctionCall(IdentifierReference(listOf("msb"), expr.position), mutableListOf(expr.left), expr.position),
+                            DataType.BYTE,
+                            true, expr.position)
+                    if (amount == 8)
+                        return msbAsByte
+                    return BinaryExpression(msbAsByte, ">>", NumericLiteralValue.optimalInteger(amount - 8, expr.position), expr.position)
+                }
+            }
+            else -> {
+            }
+        }
+        return null
+    }
+
+    private fun reorderAssociative(expr: BinaryExpression, leftVal: NumericLiteralValue?): ReorderedAssociativeBinaryExpr {
+        if (expr.operator in associativeOperators && leftVal != null) {
+            // swap left and right so that right is always the constant
+            val tmp = expr.left
+            expr.left = expr.right
+            expr.right = tmp
+            return ReorderedAssociativeBinaryExpr(expr, expr.right.constValue(program), leftVal)
+        }
+        return ReorderedAssociativeBinaryExpr(expr, leftVal, expr.right.constValue(program))
+    }
+
+    private data class ReorderedAssociativeBinaryExpr(val expr: BinaryExpression, val leftVal: NumericLiteralValue?, val rightVal: NumericLiteralValue?)
+
+}

compiler/src/prog8/optimizer/Extensions.kt

@@ -1,42 +1,44 @@
 package prog8.optimizer
 
 import prog8.ast.Program
-import prog8.ast.base.AstException
-import prog8.parser.ParsingFailedError
+import prog8.ast.base.ErrorReporter
 
 
-internal fun Program.constantFold() {
-    val optimizer = ConstantFolding(this)
-    try {
+internal fun Program.constantFold(errors: ErrorReporter) {
+    val replacer = ConstantIdentifierReplacer(this, errors)
+    replacer.visit(this)
+    if(errors.isEmpty()) {
+        replacer.applyModifications()
+
+        val optimizer = ConstantFoldingOptimizer(this)
         optimizer.visit(this)
-    } catch (ax: AstException) {
-        optimizer.addError(ax)
+        while (errors.isEmpty() && optimizer.applyModifications() > 0) {
+            optimizer.visit(this)
+        }
+
+        if(errors.isEmpty()) {
+            replacer.visit(this)
+            replacer.applyModifications()
+        }
     }
 
-    while(optimizer.errors.isEmpty() && optimizer.optimizationsDone>0) {
-        optimizer.optimizationsDone = 0
-        optimizer.visit(this)
-    }
-
-    if(optimizer.errors.isNotEmpty()) {
-        optimizer.errors.forEach { System.err.println(it) }
-        throw ParsingFailedError("There are ${optimizer.errors.size} errors.")
-    } else {
+    if(errors.isEmpty())
         modules.forEach { it.linkParents(namespace) }   // re-link in final configuration
-    }
 }
 
 
-internal fun Program.optimizeStatements(optimizeInlining: Boolean): Int {
-    val optimizer = StatementOptimizer(this, optimizeInlining)
+internal fun Program.optimizeStatements(errors: ErrorReporter): Int {
+    val optimizer = StatementOptimizer(this, errors)
     optimizer.visit(this)
+    val optimizationCount = optimizer.applyModifications()
+
     modules.forEach { it.linkParents(this.namespace) }   // re-link in final configuration
 
-    return optimizer.optimizationsDone
+    return optimizationCount
 }
 
 internal fun Program.simplifyExpressions() : Int {
-    val optimizer = SimplifyExpressions(this)
-    optimizer.visit(this)
-    return optimizer.optimizationsDone
+    val opti = ExpressionSimplifier(this)
+    opti.visit(this)
+    return opti.applyModifications()
 }

compiler/src/prog8/optimizer/SimplifyExpressions.kt

@@ -1,725 +0,0 @@
-package prog8.optimizer
-
-import prog8.ast.Program
-import prog8.ast.base.AstException
-import prog8.ast.base.DataType
-import prog8.ast.base.IntegerDatatypes
-import prog8.ast.base.NumericDatatypes
-import prog8.ast.expressions.*
-import prog8.ast.processing.IAstModifyingVisitor
-import prog8.ast.statements.Assignment
-import prog8.ast.statements.Statement
-import kotlin.math.abs
-import kotlin.math.log2
-
-/*
-    todo advanced expression optimization: common (sub) expression elimination (turn common expressions into single subroutine call + introduce variable to hold it)
-
-    Also see  https://egorbo.com/peephole-optimizations.html
-
- */
-
-internal class SimplifyExpressions(private val program: Program) : IAstModifyingVisitor {
-    var optimizationsDone: Int = 0
-
-    override fun visit(assignment: Assignment): Statement {
-        if (assignment.aug_op != null)
-            throw AstException("augmented assignments should have been converted to normal assignments before this optimizer")
-        return super.visit(assignment)
-    }
-
-    override fun visit(memread: DirectMemoryRead): Expression {
-        // @( &thing )  -->  thing
-        val addrOf = memread.addressExpression as? AddressOf
-        if(addrOf!=null)
-            return super.visit(addrOf.identifier)
-        return super.visit(memread)
-    }
-
-    override fun visit(typecast: TypecastExpression): Expression {
-        var tc = typecast
-
-        // try to statically convert a literal value into one of the desired type
-        val literal = tc.expression as? NumericLiteralValue
-        if(literal!=null) {
-            val newLiteral = literal.cast(tc.type)
-            if(newLiteral!=null && newLiteral!==literal) {
-                optimizationsDone++
-                return newLiteral
-            }
-        }
-
-        // remove redundant typecasts
-        while(true) {
-            val expr = tc.expression
-            if(expr !is TypecastExpression || expr.type!=tc.type) {
-                val assignment = typecast.parent as? Assignment
-                if(assignment!=null) {
-                    val targetDt = assignment.target.inferType(program, assignment)
-                    if(tc.expression.inferType(program)==targetDt) {
-                        optimizationsDone++
-                        return tc.expression
-                    }
-                }
-
-                val subTc = tc.expression as? TypecastExpression
-                if(subTc!=null) {
-                    // if the previous typecast was casting to a 'bigger' type, just ignore that one
-                    // if the previous typecast was casting to a similar type, ignore that one
-                    if(subTc.type largerThan tc.type || subTc.type equalsSize tc.type) {
-                        subTc.type = tc.type
-                        subTc.parent = tc.parent
-                        optimizationsDone++
-                        return subTc
-                    }
-                }
-
-                return super.visit(tc)
-            }
-
-            optimizationsDone++
-            tc = expr
-        }
-    }
-
-    override fun visit(expr: PrefixExpression): Expression {
-        if (expr.operator == "+") {
-            // +X --> X
-            optimizationsDone++
-            return expr.expression.accept(this)
-        } else if (expr.operator == "not") {
-            (expr.expression as? BinaryExpression)?.let {
-                // NOT (...)  ->   invert  ...
-                when (it.operator) {
-                    "<" -> {
-                        it.operator = ">="
-                        optimizationsDone++
-                        return it
-                    }
-                    ">" -> {
-                        it.operator = "<="
-                        optimizationsDone++
-                        return it
-                    }
-                    "<=" -> {
-                        it.operator = ">"
-                        optimizationsDone++
-                        return it
-                    }
-                    ">=" -> {
-                        it.operator = "<"
-                        optimizationsDone++
-                        return it
-                    }
-                    "==" -> {
-                        it.operator = "!="
-                        optimizationsDone++
-                        return it
-                    }
-                    "!=" -> {
-                        it.operator = "=="
-                        optimizationsDone++
-                        return it
-                    }
-                    else -> {
-                    }
-                }
-            }
-        }
-        return super.visit(expr)
-    }
-
-    override fun visit(expr: BinaryExpression): Expression {
-        super.visit(expr)
-        val leftVal = expr.left.constValue(program)
-        val rightVal = expr.right.constValue(program)
-        val constTrue = NumericLiteralValue.fromBoolean(true, expr.position)
-        val constFalse = NumericLiteralValue.fromBoolean(false, expr.position)
-
-        val leftDt = expr.left.inferType(program)
-        val rightDt = expr.right.inferType(program)
-        if (leftDt != null && rightDt != null && leftDt != rightDt) {
-            // try to convert a datatype into the other (where ddd
-            if (adjustDatatypes(expr, leftVal, leftDt, rightVal, rightDt)) {
-                optimizationsDone++
-                return expr
-            }
-        }
-
-        // Value <associativeoperator> X -->  X <associativeoperator> Value
-        if (leftVal != null && expr.operator in associativeOperators && rightVal == null) {
-            val tmp = expr.left
-            expr.left = expr.right
-            expr.right = tmp
-            optimizationsDone++
-            return expr
-        }
-
-        // X + (-A)  -->  X - A
-        if (expr.operator == "+" && (expr.right as? PrefixExpression)?.operator == "-") {
-            expr.operator = "-"
-            expr.right = (expr.right as PrefixExpression).expression
-            optimizationsDone++
-            return expr
-        }
-
-        // (-A) + X  -->  X - A
-        if (expr.operator == "+" && (expr.left as? PrefixExpression)?.operator == "-") {
-            expr.operator = "-"
-            val newRight = (expr.left as PrefixExpression).expression
-            expr.left = expr.right
-            expr.right = newRight
-            optimizationsDone++
-            return expr
-        }
-
-        // X + (-value)  -->  X - value
-        if (expr.operator == "+" && rightVal != null) {
-            val rv = rightVal.number.toDouble()
-            if (rv < 0.0) {
-                expr.operator = "-"
-                expr.right = NumericLiteralValue(rightVal.type, -rv, rightVal.position)
-                optimizationsDone++
-                return expr
-            }
-        }
-
-        // (-value) + X  -->  X - value
-        if (expr.operator == "+" && leftVal != null) {
-            val lv = leftVal.number.toDouble()
-            if (lv < 0.0) {
-                expr.operator = "-"
-                expr.right = NumericLiteralValue(leftVal.type, -lv, leftVal.position)
-                optimizationsDone++
-                return expr
-            }
-        }
-
-        // X - (-A)  -->  X + A
-        if (expr.operator == "-" && (expr.right as? PrefixExpression)?.operator == "-") {
-            expr.operator = "+"
-            expr.right = (expr.right as PrefixExpression).expression
-            optimizationsDone++
-            return expr
-        }
-
-        // X - (-value)  -->  X + value
-        if (expr.operator == "-" && rightVal != null) {
-            val rv = rightVal.number.toDouble()
-            if (rv < 0.0) {
-                expr.operator = "+"
-                expr.right = NumericLiteralValue(rightVal.type, -rv, rightVal.position)
-                optimizationsDone++
-                return expr
-            }
-        }
-
-        if (expr.operator == "+" || expr.operator == "-"
-                && leftVal == null && rightVal == null
-                && leftDt in NumericDatatypes && rightDt in NumericDatatypes) {
-            val leftBinExpr = expr.left as? BinaryExpression
-            val rightBinExpr = expr.right as? BinaryExpression
-            if (leftBinExpr?.operator == "*") {
-                if (expr.operator == "+") {
-                    // Y*X + X  ->  X*(Y - 1)
-                    // X*Y + X  ->  X*(Y - 1)
-                    val x = expr.right
-                    val y = determineY(x, leftBinExpr)
-                    if(y!=null) {
-                        val yPlus1 = BinaryExpression(y, "+", NumericLiteralValue(leftDt!!, 1, y.position), y.position)
-                        return BinaryExpression(x, "*", yPlus1, x.position)
-                    }
-                } else {
-                    // Y*X - X  ->  X*(Y - 1)
-                    // X*Y - X  ->  X*(Y - 1)
-                    val x = expr.right
-                    val y = determineY(x, leftBinExpr)
-                    if(y!=null) {
-                        val yMinus1 = BinaryExpression(y, "-", NumericLiteralValue(leftDt!!, 1, y.position), y.position)
-                        return BinaryExpression(x, "*", yMinus1, x.position)
-                    }
-                }
-            }
-            else if(rightBinExpr?.operator=="*") {
-                if(expr.operator=="+") {
-                    // X + Y*X  ->  X*(Y + 1)
-                    // X + X*Y  ->  X*(Y + 1)
-                    val x = expr.left
-                    val y = determineY(x, rightBinExpr)
-                    if(y!=null) {
-                        val yPlus1 = BinaryExpression(y, "+", NumericLiteralValue.optimalInteger(1, y.position), y.position)
-                        return BinaryExpression(x, "*", yPlus1, x.position)
-                    }
-                } else {
-                    // X - Y*X  ->  X*(1 - Y)
-                    // X - X*Y  ->  X*(1 - Y)
-                    val x = expr.left
-                    val y = determineY(x, rightBinExpr)
-                    if(y!=null) {
-                        val oneMinusY = BinaryExpression(NumericLiteralValue.optimalInteger(1, y.position), "-", y, y.position)
-                        return BinaryExpression(x, "*", oneMinusY, x.position)
-                    }
-                }
-            }
-        }
-
-
-        // simplify when a term is constant and determines the outcome
-        when (expr.operator) {
-            "or" -> {
-                if ((leftVal != null && leftVal.asBooleanValue) || (rightVal != null && rightVal.asBooleanValue)) {
-                    optimizationsDone++
-                    return constTrue
-                }
-                if (leftVal != null && !leftVal.asBooleanValue) {
-                    optimizationsDone++
-                    return expr.right
-                }
-                if (rightVal != null && !rightVal.asBooleanValue) {
-                    optimizationsDone++
-                    return expr.left
-                }
-            }
-            "and" -> {
-                if ((leftVal != null && !leftVal.asBooleanValue) || (rightVal != null && !rightVal.asBooleanValue)) {
-                    optimizationsDone++
-                    return constFalse
-                }
-                if (leftVal != null && leftVal.asBooleanValue) {
-                    optimizationsDone++
-                    return expr.right
-                }
-                if (rightVal != null && rightVal.asBooleanValue) {
-                    optimizationsDone++
-                    return expr.left
-                }
-            }
-            "xor" -> {
-                if (leftVal != null && !leftVal.asBooleanValue) {
-                    optimizationsDone++
-                    return expr.right
-                }
-                if (rightVal != null && !rightVal.asBooleanValue) {
-                    optimizationsDone++
-                    return expr.left
-                }
-                if (leftVal != null && leftVal.asBooleanValue) {
-                    optimizationsDone++
-                    return PrefixExpression("not", expr.right, expr.right.position)
-                }
-                if (rightVal != null && rightVal.asBooleanValue) {
-                    optimizationsDone++
-                    return PrefixExpression("not", expr.left, expr.left.position)
-                }
-            }
-            "|", "^" -> {
-                if (leftVal != null && !leftVal.asBooleanValue) {
-                    optimizationsDone++
-                    return expr.right
-                }
-                if (rightVal != null && !rightVal.asBooleanValue) {
-                    optimizationsDone++
-                    return expr.left
-                }
-            }
-            "&" -> {
-                if (leftVal != null && !leftVal.asBooleanValue) {
-                    optimizationsDone++
-                    return constFalse
-                }
-                if (rightVal != null && !rightVal.asBooleanValue) {
-                    optimizationsDone++
-                    return constFalse
-                }
-            }
-            "*" -> return optimizeMultiplication(expr, leftVal, rightVal)
-            "/" -> return optimizeDivision(expr, leftVal, rightVal)
-            "+" -> return optimizeAdd(expr, leftVal, rightVal)
-            "-" -> return optimizeSub(expr, leftVal, rightVal)
-            "**" -> return optimizePower(expr, leftVal, rightVal)
-            "%" -> return optimizeRemainder(expr, leftVal, rightVal)
-        }
-        return expr
-    }
-
-    private fun determineY(x: Expression, subBinExpr: BinaryExpression): Expression? {
-        return when {
-            subBinExpr.left isSameAs x -> subBinExpr.right
-            subBinExpr.right isSameAs x -> subBinExpr.left
-            else -> null
-        }
-    }
-
-    private fun adjustDatatypes(expr: BinaryExpression,
-                                leftConstVal: NumericLiteralValue?, leftDt: DataType,
-                                rightConstVal: NumericLiteralValue?, rightDt: DataType): Boolean {
-
-        fun adjust(value: NumericLiteralValue, targetDt: DataType): Pair<Boolean, NumericLiteralValue>{
-            if(value.type==targetDt)
-                return Pair(false, value)
-            when(value.type) {
-                DataType.UBYTE -> {
-                    if (targetDt == DataType.BYTE) {
-                        if(value.number.toInt() < 127)
-                            return Pair(true, NumericLiteralValue(targetDt, value.number.toShort(), value.position))
-                    }
-                    else if (targetDt == DataType.UWORD || targetDt == DataType.WORD)
-                        return Pair(true, NumericLiteralValue(targetDt, value.number.toInt(), value.position))
-                }
-                DataType.BYTE -> {
-                    if (targetDt == DataType.UBYTE) {
-                        if(value.number.toInt() >= 0)
-                            return Pair(true, NumericLiteralValue(targetDt, value.number.toInt(), value.position))
-                    }
-                    else if (targetDt == DataType.UWORD) {
-                        if(value.number.toInt() >= 0)
-                            return Pair(true, NumericLiteralValue(targetDt, value.number.toInt(), value.position))
-                    }
-                    else if (targetDt == DataType.WORD) return Pair(true, NumericLiteralValue(targetDt, value.number.toInt(), value.position))
-                }
-                DataType.UWORD -> {
-                    if (targetDt == DataType.UBYTE) {
-                        if(value.number.toInt() <= 255)
-                            return Pair(true, NumericLiteralValue(targetDt, value.number.toShort(), value.position))
-                    }
-                    else if (targetDt == DataType.BYTE) {
-                        if(value.number.toInt() <= 127)
-                            return Pair(true, NumericLiteralValue(targetDt, value.number.toShort(), value.position))
-                    }
-                    else if (targetDt == DataType.WORD) {
-                        if(value.number.toInt() <= 32767)
-                            return Pair(true, NumericLiteralValue(targetDt, value.number.toInt(), value.position))
-                    }
-                }
-                DataType.WORD -> {
-                    if (targetDt == DataType.UBYTE) {
-                        if(value.number.toInt() in 0..255)
-                            return Pair(true, NumericLiteralValue(targetDt, value.number.toShort(), value.position))
-                    }
-                    else if (targetDt == DataType.BYTE) {
-                        if(value.number.toInt() in -128..127)
-                            return Pair(true, NumericLiteralValue(targetDt, value.number.toShort(), value.position))
-                    }
-                    else if (targetDt == DataType.UWORD) {
-                        if(value.number.toInt() >= 0)
-                            return Pair(true, NumericLiteralValue(targetDt, value.number.toShort(), value.position))
-                    }
-                }
-                else -> {}
-            }
-            return Pair(false, value)
-        }
-
-        if(leftConstVal==null && rightConstVal!=null) {
-            if(leftDt largerThan rightDt) {
-                val (adjusted, newValue) = adjust(rightConstVal, leftDt)
-                if (adjusted) {
-                    expr.right = newValue
-                    optimizationsDone++
-                    return true
-                }
-            }
-            return false
-        } else if(leftConstVal!=null && rightConstVal==null) {
-            if(rightDt largerThan leftDt) {
-                val (adjusted, newValue) = adjust(leftConstVal, rightDt)
-                if (adjusted) {
-                    expr.left = newValue
-                    optimizationsDone++
-                    return true
-                }
-            }
-            return false
-        } else {
-            return false    // two const values, don't adjust (should have been const-folded away)
-        }
-    }
-
-    private data class ReorderedAssociativeBinaryExpr(val expr: BinaryExpression, val leftVal: NumericLiteralValue?, val rightVal: NumericLiteralValue?)
-
-    private fun reorderAssociative(expr: BinaryExpression, leftVal: NumericLiteralValue?): ReorderedAssociativeBinaryExpr {
-        if(expr.operator in associativeOperators && leftVal!=null) {
-            // swap left and right so that right is always the constant
-            val tmp = expr.left
-            expr.left = expr.right
-            expr.right = tmp
-            optimizationsDone++
-            return ReorderedAssociativeBinaryExpr(expr, expr.right.constValue(program), leftVal)
-        }
-        return ReorderedAssociativeBinaryExpr(expr, leftVal, expr.right.constValue(program))
-    }
-
-    private fun optimizeAdd(pexpr: BinaryExpression, pleftVal: NumericLiteralValue?, prightVal: NumericLiteralValue?): Expression {
-        if(pleftVal==null && prightVal==null)
-            return pexpr
-
-        val (expr, _, rightVal) = reorderAssociative(pexpr, pleftVal)
-        if(rightVal!=null) {
-            // right value is a constant, see if we can optimize
-            val rightConst: NumericLiteralValue = rightVal
-            when(rightConst.number.toDouble()) {
-                0.0 -> {
-                    // left
-                    optimizationsDone++
-                    return expr.left
-                }
-            }
-        }
-        // no need to check for left val constant (because of associativity)
-
-        return expr
-    }
-
-    private fun optimizeSub(expr: BinaryExpression, leftVal: NumericLiteralValue?, rightVal: NumericLiteralValue?): Expression {
-        if(leftVal==null && rightVal==null)
-            return expr
-
-        if(rightVal!=null) {
-            // right value is a constant, see if we can optimize
-            val rightConst: NumericLiteralValue = rightVal
-            when(rightConst.number.toDouble()) {
-                0.0 -> {
-                    // left
-                    optimizationsDone++
-                    return expr.left
-                }
-            }
-        }
-        if(leftVal!=null) {
-            // left value is a constant, see if we can optimize
-            when(leftVal.number.toDouble()) {
-                0.0 -> {
-                    // -right
-                    optimizationsDone++
-                    return PrefixExpression("-", expr.right, expr.position)
-                }
-            }
-        }
-
-        return expr
-    }
-
-    private fun optimizePower(expr: BinaryExpression, leftVal: NumericLiteralValue?, rightVal: NumericLiteralValue?): Expression {
-        if(leftVal==null && rightVal==null)
-            return expr
-
-        if(rightVal!=null) {
-            // right value is a constant, see if we can optimize
-            val rightConst: NumericLiteralValue = rightVal
-            when(rightConst.number.toDouble()) {
-                -3.0 -> {
-                    // -1/(left*left*left)
-                    optimizationsDone++
-                    return BinaryExpression(NumericLiteralValue(DataType.FLOAT, -1.0, expr.position), "/",
-                            BinaryExpression(expr.left, "*", BinaryExpression(expr.left, "*", expr.left, expr.position), expr.position),
-                            expr.position)
-                }
-                -2.0 -> {
-                    // -1/(left*left)
-                    optimizationsDone++
-                    return BinaryExpression(NumericLiteralValue(DataType.FLOAT, -1.0, expr.position), "/",
-                            BinaryExpression(expr.left, "*", expr.left, expr.position),
-                            expr.position)
-                }
-                -1.0 -> {
-                    // -1/left
-                    optimizationsDone++
-                    return BinaryExpression(NumericLiteralValue(DataType.FLOAT, -1.0, expr.position), "/",
-                            expr.left, expr.position)
-                }
-                0.0 -> {
-                    // 1
-                    optimizationsDone++
-                    return NumericLiteralValue(rightConst.type, 1, expr.position)
-                }
-                0.5 -> {
-                    // sqrt(left)
-                    optimizationsDone++
-                    return FunctionCall(IdentifierReference(listOf("sqrt"), expr.position), mutableListOf(expr.left), expr.position)
-                }
-                1.0 -> {
-                    // left
-                    optimizationsDone++
-                    return expr.left
-                }
-                2.0 -> {
-                    // left*left
-                    optimizationsDone++
-                    return BinaryExpression(expr.left, "*", expr.left, expr.position)
-                }
-                3.0 -> {
-                    // left*left*left
-                    optimizationsDone++
-                    return BinaryExpression(expr.left, "*", BinaryExpression(expr.left, "*", expr.left, expr.position), expr.position)
-                }
-            }
-        }
-        if(leftVal!=null) {
-            // left value is a constant, see if we can optimize
-            when(leftVal.number.toDouble()) {
-                -1.0 -> {
-                    // -1
-                    optimizationsDone++
-                    return NumericLiteralValue(DataType.FLOAT, -1.0, expr.position)
-                }
-                0.0 -> {
-                    // 0
-                    optimizationsDone++
-                    return NumericLiteralValue(leftVal.type, 0, expr.position)
-                }
-                1.0 -> {
-                    //1
-                    optimizationsDone++
-                    return NumericLiteralValue(leftVal.type, 1, expr.position)
-                }
-
-            }
-        }
-
-        return expr
-    }
-
-    private fun optimizeRemainder(expr: BinaryExpression, leftVal: NumericLiteralValue?, rightVal: NumericLiteralValue?): Expression {
-        if(leftVal==null && rightVal==null)
-            return expr
-
-        // simplify assignments  A = B <operator> C
-
-        val cv = rightVal?.number?.toInt()?.toDouble()
-        when(expr.operator) {
-            "%" -> {
-                if (cv == 1.0) {
-                    optimizationsDone++
-                    return NumericLiteralValue(expr.inferType(program)!!, 0, expr.position)
-                } else if (cv == 2.0) {
-                    optimizationsDone++
-                    expr.operator = "&"
-                    expr.right = NumericLiteralValue.optimalInteger(1, expr.position)
-                    return expr
-                }
-            }
-        }
-        return expr
-
-    }
-
-    private fun optimizeDivision(expr: BinaryExpression, leftVal: NumericLiteralValue?, rightVal: NumericLiteralValue?): Expression {
-        if(leftVal==null && rightVal==null)
-            return expr
-
-        // cannot shuffle assiciativity with division!
-
-        if(rightVal!=null) {
-            // right value is a constant, see if we can optimize
-            val rightConst: NumericLiteralValue = rightVal
-            val cv = rightConst.number.toDouble()
-            val leftDt = expr.left.inferType(program)
-            when(cv) {
-                -1.0 -> {
-                    //  '/' -> -left
-                    if (expr.operator == "/") {
-                        optimizationsDone++
-                        return PrefixExpression("-", expr.left, expr.position)
-                    }
-                }
-                1.0 -> {
-                    //  '/' -> left
-                    if (expr.operator == "/") {
-                        optimizationsDone++
-                        return expr.left
-                    }
-                }
-                2.0, 4.0, 8.0, 16.0, 32.0, 64.0, 128.0, 256.0, 512.0, 1024.0, 2048.0, 4096.0, 8192.0, 16384.0, 32768.0, 65536.0 -> {
-                    if(leftDt in IntegerDatatypes) {
-                        // divided by a power of two => shift right
-                        optimizationsDone++
-                        val numshifts = log2(cv).toInt()
-                        return BinaryExpression(expr.left, ">>", NumericLiteralValue.optimalInteger(numshifts, expr.position), expr.position)
-                    }
-                }
-                -2.0, -4.0, -8.0, -16.0, -32.0, -64.0, -128.0, -256.0, -512.0, -1024.0, -2048.0, -4096.0, -8192.0, -16384.0, -32768.0, -65536.0 -> {
-                    if(leftDt in IntegerDatatypes) {
-                        // divided by a negative power of two => negate, then shift right
-                        optimizationsDone++
-                        val numshifts = log2(-cv).toInt()
-                        return BinaryExpression(PrefixExpression("-", expr.left, expr.position), ">>", NumericLiteralValue.optimalInteger(numshifts, expr.position), expr.position)
-                    }
-                }
-            }
-
-            if (leftDt == DataType.UBYTE) {
-                if(abs(rightConst.number.toDouble()) >= 256.0) {
-                    optimizationsDone++
-                    return NumericLiteralValue(DataType.UBYTE, 0, expr.position)
-                }
-            }
-            else if (leftDt == DataType.UWORD) {
-                if(abs(rightConst.number.toDouble()) >= 65536.0) {
-                    optimizationsDone++
-                    return NumericLiteralValue(DataType.UBYTE, 0, expr.position)
-                }
-            }
-        }
-
-        if(leftVal!=null) {
-            // left value is a constant, see if we can optimize
-            when(leftVal.number.toDouble()) {
-                0.0 -> {
-                    // 0
-                    optimizationsDone++
-                    return NumericLiteralValue(leftVal.type, 0, expr.position)
-                }
-            }
-        }
-
-        return expr
-    }
-
-    private fun optimizeMultiplication(pexpr: BinaryExpression, pleftVal: NumericLiteralValue?, prightVal: NumericLiteralValue?): Expression {
-        if(pleftVal==null && prightVal==null)
-            return pexpr
-
-        val (expr, _, rightVal) = reorderAssociative(pexpr, pleftVal)
-        if(rightVal!=null) {
-            // right value is a constant, see if we can optimize
-            val leftValue: Expression = expr.left
-            val rightConst: NumericLiteralValue = rightVal
-            when(val cv = rightConst.number.toDouble()) {
-                -1.0 -> {
-                    // -left
-                    optimizationsDone++
-                    return PrefixExpression("-", leftValue, expr.position)
-                }
-                0.0 -> {
-                    // 0
-                    optimizationsDone++
-                    return NumericLiteralValue(rightConst.type, 0, expr.position)
-                }
-                1.0 -> {
-                    // left
-                    optimizationsDone++
-                    return expr.left
-                }
-                2.0, 4.0, 8.0, 16.0, 32.0, 64.0, 128.0, 256.0, 512.0, 1024.0, 2048.0, 4096.0, 8192.0, 16384.0, 32768.0, 65536.0 -> {
-                    if(leftValue.inferType(program) in IntegerDatatypes) {
-                        // times a power of two => shift left
-                        optimizationsDone++
-                        val numshifts = log2(cv).toInt()
-                        return BinaryExpression(expr.left, "<<", NumericLiteralValue.optimalInteger(numshifts, expr.position), expr.position)
-                    }
-                }
-                -2.0, -4.0, -8.0, -16.0, -32.0, -64.0, -128.0, -256.0, -512.0, -1024.0, -2048.0, -4096.0, -8192.0, -16384.0, -32768.0, -65536.0 -> {
-                    if(leftValue.inferType(program) in IntegerDatatypes) {
-                        // times a negative power of two => negate, then shift left
-                        optimizationsDone++
-                        val numshifts = log2(-cv).toInt()
-                        return BinaryExpression(PrefixExpression("-", expr.left, expr.position), "<<", NumericLiteralValue.optimalInteger(numshifts, expr.position), expr.position)
-                    }
-                }
-            }
-        }
-        // no need to check for left val constant (because of associativity)
-
-        return expr
-    }
-}

compiler/src/prog8/optimizer/UnusedCodeRemover.kt

@@ -0,0 +1,41 @@
+package prog8.optimizer
+
+import prog8.ast.Node
+import prog8.ast.Program
+import prog8.ast.processing.AstWalker
+import prog8.ast.processing.IAstModification
+import prog8.ast.statements.Block
+
+/*
+    TODO: remove unreachable code after return and exit()
+*/
+
+internal class UnusedCodeRemover: AstWalker() {
+
+    override fun before(program: Program, parent: Node): Iterable<IAstModification> {
+        val callgraph = CallGraph(program)
+        val removals = mutableListOf<IAstModification>()
+
+        // remove all subroutines that aren't called, or are empty
+        val entrypoint = program.entrypoint()
+        program.modules.forEach {
+            callgraph.forAllSubroutines(it) { sub ->
+                if (sub !== entrypoint && !sub.keepAlways && (callgraph.calledBy[sub].isNullOrEmpty() || (sub.containsNoCodeNorVars() && !sub.isAsmSubroutine)))
+                    removals.add(IAstModification.Remove(sub, sub.definingScope() as Node))
+            }
+        }
+
+        program.modules.flatMap { it.statements }.filterIsInstance<Block>().forEach { block ->
+            if (block.containsNoCodeNorVars() && "force_output" !in block.options())
+                removals.add(IAstModification.Remove(block, block.definingScope() as Node))
+        }
+
+        // remove modules that are not imported, or are empty (unless it's a library modules)
+        program.modules.forEach {
+            if (!it.isLibraryModule && (it.importedBy.isEmpty() || it.containsNoCodeNorVars()))
+                removals.add(IAstModification.Remove(it, it.parent))
+        }
+
+        return removals
+    }
+}

compiler/src/prog8/parser/ModuleParsing.kt

@@ -4,11 +4,13 @@ import org.antlr.v4.runtime.*
 import prog8.ast.Module
 import prog8.ast.Program
 import prog8.ast.antlr.toAst
+import prog8.ast.base.ErrorReporter
 import prog8.ast.base.Position
 import prog8.ast.base.SyntaxError
 import prog8.ast.base.checkImportedValid
 import prog8.ast.statements.Directive
 import prog8.ast.statements.DirectiveArg
+import prog8.pathFrom
 import java.io.InputStream
 import java.nio.file.Files
 import java.nio.file.Path
@@ -32,114 +34,117 @@ internal class CustomLexer(val modulePath: Path, input: CharStream?) : prog8Lexe
 internal fun moduleName(fileName: Path) = fileName.toString().substringBeforeLast('.')
 
 
-internal fun importModule(program: Program, filePath: Path): Module {
-    print("importing '${moduleName(filePath.fileName)}'")
-    if(filePath.parent!=null) {
-        var importloc = filePath.toString()
-        val curdir = Paths.get("").toAbsolutePath().toString()
-        if(importloc.startsWith(curdir))
-            importloc = "." + importloc.substring(curdir.length)
-        println(" (from '$importloc')")
-    }
-    else
-        println("")
-    if(!Files.isReadable(filePath))
-        throw ParsingFailedError("No such file: $filePath")
+internal class ModuleImporter() {
 
-    val input = CharStreams.fromPath(filePath)
-    return importModule(program, input, filePath, false)
-}
+    internal fun importModule(program: Program, filePath: Path): Module {
+        print("importing '${moduleName(filePath.fileName)}'")
+        if(filePath.parent!=null) {
+            var importloc = filePath.toString()
+            val curdir = Paths.get("").toAbsolutePath().toString()
+            if(importloc.startsWith(curdir))
+                importloc = "." + importloc.substring(curdir.length)
+            println(" (from '$importloc')")
+        }
+        else
+            println("")
+        if(!Files.isReadable(filePath))
+            throw ParsingFailedError("No such file: $filePath")
 
-internal fun importLibraryModule(program: Program, name: String): Module? {
-    val import = Directive("%import", listOf(
-            DirectiveArg("", name, 42, position = Position("<<<implicit-import>>>", 0, 0, 0))
-    ), Position("<<<implicit-import>>>", 0, 0, 0))
-    return executeImportDirective(program, import, Paths.get(""))
-}
-
-internal fun importModule(program: Program, stream: CharStream, modulePath: Path, isLibrary: Boolean): Module {
-    val moduleName = moduleName(modulePath.fileName)
-    val lexer = CustomLexer(modulePath, stream)
-    val lexerErrors = LexerErrorListener()
-    lexer.addErrorListener(lexerErrors)
-    val tokens = CommentHandlingTokenStream(lexer)
-    val parser = prog8Parser(tokens)
-    val parseTree = parser.module()
-    val numberOfErrors = parser.numberOfSyntaxErrors + lexerErrors.numberOfErrors
-    if(numberOfErrors > 0)
-        throw ParsingFailedError("There are $numberOfErrors errors in '$moduleName'.")
-
-    // You can do something with the parsed comments:
-    // tokens.commentTokens().forEach { println(it) }
-
-    // convert to Ast
-    val moduleAst = parseTree.toAst(moduleName, isLibrary, modulePath)
-    moduleAst.program = program
-    moduleAst.linkParents(program.namespace)
-    program.modules.add(moduleAst)
-
-    // accept additional imports
-    val lines = moduleAst.statements.toMutableList()
-    lines.asSequence()
-         .mapIndexed { i, it -> Pair(i, it) }
-         .filter { (it.second as? Directive)?.directive == "%import" }
-         .forEach { executeImportDirective(program, it.second as Directive, modulePath) }
-
-    moduleAst.statements = lines
-    return moduleAst
-}
-
-private fun discoverImportedModuleFile(name: String, source: Path, position: Position?): Path {
-    val fileName = "$name.p8"
-    val locations = mutableListOf(Paths.get(source.parent.toString()))
-
-    val propPath = System.getProperty("prog8.libdir")
-    if(propPath!=null)
-        locations.add(Paths.get(propPath))
-    val envPath = System.getenv("PROG8_LIBDIR")
-    if(envPath!=null)
-        locations.add(Paths.get(envPath))
-    locations.add(Paths.get(Paths.get("").toAbsolutePath().toString(), "prog8lib"))
-
-    locations.forEach {
-        val file = Paths.get(it.toString(), fileName)
-        if (Files.isReadable(file)) return file
+        val input = CharStreams.fromPath(filePath)
+        return importModule(program, input, filePath, false)
     }
 
-    throw ParsingFailedError("$position Import: no module source file '$fileName' found  (I've looked in: $locations)")
-}
+    internal fun importLibraryModule(program: Program, name: String): Module? {
+        val import = Directive("%import", listOf(
+                DirectiveArg("", name, 42, position = Position("<<<implicit-import>>>", 0, 0, 0))
+        ), Position("<<<implicit-import>>>", 0, 0, 0))
+        return executeImportDirective(program, import, Paths.get(""))
+    }
 
-private fun executeImportDirective(program: Program, import: Directive, source: Path): Module? {
-    if(import.directive!="%import" || import.args.size!=1 || import.args[0].name==null)
-        throw SyntaxError("invalid import directive", import.position)
-    val moduleName = import.args[0].name!!
-    if("$moduleName.p8" == import.position.file)
-        throw SyntaxError("cannot import self", import.position)
+    private fun importModule(program: Program, stream: CharStream, modulePath: Path, isLibrary: Boolean): Module {
+        val moduleName = moduleName(modulePath.fileName)
+        val lexer = CustomLexer(modulePath, stream)
+        val lexerErrors = LexerErrorListener()
+        lexer.addErrorListener(lexerErrors)
+        val tokens = CommentHandlingTokenStream(lexer)
+        val parser = prog8Parser(tokens)
+        val parseTree = parser.module()
+        val numberOfErrors = parser.numberOfSyntaxErrors + lexerErrors.numberOfErrors
+        if(numberOfErrors > 0)
+            throw ParsingFailedError("There are $numberOfErrors errors in '$moduleName'.")
 
-    val existing = program.modules.singleOrNull { it.name == moduleName }
-    if(existing!=null)
-        return null
+        // You can do something with the parsed comments:
+        // tokens.commentTokens().forEach { println(it) }
 
-    val resource = tryGetEmbeddedResource(moduleName+".p8")
-    val importedModule =
-        if(resource!=null) {
-            // load the module from the embedded resource
-            resource.use {
-                if(import.args[0].int==42)
-                    println("importing '$moduleName' (library, auto)")
-                else
-                    println("importing '$moduleName' (library)")
-                importModule(program, CharStreams.fromStream(it), Paths.get("@embedded@/$moduleName"), true)
-            }
-        } else {
-            val modulePath = discoverImportedModuleFile(moduleName, source, import.position)
-            importModule(program, modulePath)
+        // convert to Ast
+        val moduleAst = parseTree.toAst(moduleName, isLibrary, modulePath)
+        moduleAst.program = program
+        moduleAst.linkParents(program.namespace)
+        program.modules.add(moduleAst)
+
+        // accept additional imports
+        val lines = moduleAst.statements.toMutableList()
+        lines.asSequence()
+                .mapIndexed { i, it -> Pair(i, it) }
+                .filter { (it.second as? Directive)?.directive == "%import" }
+                .forEach { executeImportDirective(program, it.second as Directive, modulePath) }
+
+        moduleAst.statements = lines
+        return moduleAst
+    }
+
+    private fun discoverImportedModuleFile(name: String, source: Path, position: Position?): Path {
+        val fileName = "$name.p8"
+        val locations = mutableListOf(source.parent)
+
+        val propPath = System.getProperty("prog8.libdir")
+        if(propPath!=null)
+            locations.add(pathFrom(propPath))
+        val envPath = System.getenv("PROG8_LIBDIR")
+        if(envPath!=null)
+            locations.add(pathFrom(envPath))
+        locations.add(Paths.get(Paths.get("").toAbsolutePath().toString(), "prog8lib"))
+
+        locations.forEach {
+            val file = pathFrom(it.toString(), fileName)
+            if (Files.isReadable(file)) return file
         }
 
-    importedModule.checkImportedValid()
-    return importedModule
-}
+        throw ParsingFailedError("$position Import: no module source file '$fileName' found  (I've looked in: $locations)")
+    }
 
-internal fun tryGetEmbeddedResource(name: String): InputStream? {
-    return object{}.javaClass.getResourceAsStream("/prog8lib/$name")
+    private fun executeImportDirective(program: Program, import: Directive, source: Path): Module? {
+        if(import.directive!="%import" || import.args.size!=1 || import.args[0].name==null)
+            throw SyntaxError("invalid import directive", import.position)
+        val moduleName = import.args[0].name!!
+        if("$moduleName.p8" == import.position.file)
+            throw SyntaxError("cannot import self", import.position)
+
+        val existing = program.modules.singleOrNull { it.name == moduleName }
+        if(existing!=null)
+            return null
+
+        val resource = tryGetEmbeddedResource("$moduleName.p8")
+        val importedModule =
+                if(resource!=null) {
+                    // load the module from the embedded resource
+                    resource.use {
+                        if(import.args[0].int==42)
+                            println("importing '$moduleName' (library, auto)")
+                        else
+                            println("importing '$moduleName' (library)")
+                        importModule(program, CharStreams.fromStream(it), Paths.get("@embedded@/$moduleName"), true)
+                    }
+                } else {
+                    val modulePath = discoverImportedModuleFile(moduleName, source, import.position)
+                    importModule(program, modulePath)
+                }
+
+        importedModule.checkImportedValid()
+        return importedModule
+    }
+
+    private fun tryGetEmbeddedResource(name: String): InputStream? {
+        return object{}.javaClass.getResourceAsStream("/prog8lib/$name")
+    }
 }

compiler/src/prog8/server/dbus/IrmenDbusTest.kt

@@ -0,0 +1,22 @@
+package prog8.server.dbus
+
+//import org.freedesktop.dbus.interfaces.DBusInterface
+//
+//
+//interface IrmenDbusTest: DBusInterface
+//{
+//    fun Status(address: String): Map<Int, String>
+//}
+//
+//
+//internal class TestService: IrmenDbusTest {
+//    override fun Status(address: String): Map<Int, String> {
+//        return mapOf(
+//            5 to "hello",
+//            42 to address
+//        )
+//    }
+//
+//    override fun isRemote() = true
+//    override fun getObjectPath() = "/razorvine/TestService"
+//}

compiler/src/prog8/server/dbus/clientmain.kt

@@ -0,0 +1,17 @@
+package prog8.server.dbus
+
+
+//import org.freedesktop.dbus.connections.impl.DBusConnection
+//
+//
+//fun main() {
+//    DBusConnection.getConnection(DBusConnection.DBusBusType.SESSION).use {
+//        println(it.names.toList())
+//        println(it.uniqueName)
+//        println(it.address)
+//        println(it.machineId)
+//        val obj = it.getRemoteObject("local.net.razorvine.dbus.test", "/razorvine/TestService", IrmenDbusTest::class.java)
+//        println(obj.Status("irmen"))
+//    }
+//}
+//

compiler/src/prog8/server/dbus/testdbus.kt

@@ -0,0 +1,18 @@
+package prog8.server.dbus
+
+//import org.freedesktop.dbus.connections.impl.DBusConnection
+//
+//
+//fun main() {
+//    DBusConnection.getConnection(DBusConnection.DBusBusType.SESSION).use {
+//        it.requestBusName("local.net.razorvine.dbus.test")
+//        println(it.names.toList())
+//        println(it.uniqueName)
+//        println(it.address)
+//        println(it.machineId)
+//        val service = TestService()
+//        it.exportObject(service.objectPath, service)
+//
+//        Thread.sleep(100000)
+//    }
+//}

compiler/src/prog8/vm/RuntimeValue.kt

@@ -1,633 +0,0 @@
-package prog8.vm
-
-import prog8.ast.base.*
-import prog8.ast.expressions.NumericLiteralValue
-import prog8.ast.expressions.ReferenceLiteralValue
-import prog8.compiler.HeapValues
-import prog8.compiler.target.c64.Petscii
-import kotlin.math.abs
-import kotlin.math.pow
-
-
-/**
- * Rather than a literal value (NumericLiteralValue) that occurs in the parsed source code,
- * this runtime value can be used to *execute* the parsed Ast (or another intermediary form)
- * It contains a value of a variable during run time of the program and provides arithmetic operations on the value.
- */
-open class RuntimeValue(val type: DataType, num: Number?=null, val str: String?=null,
-                        val array: Array<Number>?=null, val heapId: Int?=null) {
-
-    val byteval: Short?
-    val wordval: Int?
-    val floatval: Double?
-    val asBoolean: Boolean
-
-    companion object {
-        fun fromLv(literalValue: NumericLiteralValue): RuntimeValue {
-            return RuntimeValue(literalValue.type, num = literalValue.number)
-        }
-
-        fun fromLv(literalValue: ReferenceLiteralValue, heap: HeapValues): RuntimeValue {
-            return when(literalValue.type) {
-                in StringDatatypes -> fromHeapId(literalValue.heapId!!, heap)
-                in ArrayDatatypes -> fromHeapId(literalValue.heapId!!, heap)
-                else -> throw IllegalArgumentException("weird source value $literalValue")
-            }
-        }
-
-        fun fromHeapId(heapId: Int, heap: HeapValues): RuntimeValue {
-            val value = heap.get(heapId)
-            return when {
-                value.type in StringDatatypes ->
-                    RuntimeValue(value.type, str = value.str!!, heapId = heapId)
-                value.type in ArrayDatatypes ->
-                    if (value.type == DataType.ARRAY_F) {
-                        RuntimeValue(value.type, array = value.doubleArray!!.toList().toTypedArray(), heapId = heapId)
-                    } else {
-                        val array = value.array!!
-                        val resultArray = mutableListOf<Number>()
-                        for(elt in array.withIndex()){
-                            if(elt.value.integer!=null)
-                                resultArray.add(elt.value.integer!!)
-                            else {
-                                TODO("ADDRESSOF ${elt.value}")
-                            }
-                        }
-                        RuntimeValue(value.type, array = resultArray.toTypedArray(), heapId = heapId)
-                        //RuntimeValue(value.type, array = array.map { it.integer!! }.toTypedArray(), heapId = heapId)
-                    }
-                else -> throw IllegalArgumentException("weird value type on heap $value")
-            }
-        }
-
-    }
-
-    init {
-        when(type) {
-            DataType.UBYTE -> {
-                val inum = num!!.toInt()
-                if(inum !in 0 .. 255)
-                    throw IllegalArgumentException("invalid value for ubyte: $inum")
-                byteval = inum.toShort()
-                wordval = null
-                floatval = null
-                asBoolean = byteval != 0.toShort()
-            }
-            DataType.BYTE -> {
-                val inum = num!!.toInt()
-                if(inum !in -128 .. 127)
-                    throw IllegalArgumentException("invalid value for byte: $inum")
-                byteval = inum.toShort()
-                wordval = null
-                floatval = null
-                asBoolean = byteval != 0.toShort()
-            }
-            DataType.UWORD -> {
-                val inum = num!!.toInt()
-                if(inum !in 0 .. 65535)
-                    throw IllegalArgumentException("invalid value for uword: $inum")
-                wordval = inum
-                byteval = null
-                floatval = null
-                asBoolean = wordval != 0
-            }
-            DataType.WORD -> {
-                val inum = num!!.toInt()
-                if(inum !in -32768 .. 32767)
-                    throw IllegalArgumentException("invalid value for word: $inum")
-                wordval = inum
-                byteval = null
-                floatval = null
-                asBoolean = wordval != 0
-            }
-            DataType.FLOAT -> {
-                floatval = num!!.toDouble()
-                byteval = null
-                wordval = null
-                asBoolean = floatval != 0.0
-            }
-            else -> {
-                byteval = null
-                wordval = null
-                floatval = null
-                asBoolean = true
-            }
-        }
-    }
-
-    override fun toString(): String {
-        return when(type) {
-            DataType.UBYTE -> "ub:%02x".format(byteval)
-            DataType.BYTE -> {
-                if(byteval!!<0)
-                    "b:-%02x".format(abs(byteval.toInt()))
-                else
-                    "b:%02x".format(byteval)
-            }
-            DataType.UWORD -> "uw:%04x".format(wordval)
-            DataType.WORD -> {
-                if(wordval!!<0)
-                    "w:-%04x".format(abs(wordval))
-                else
-                    "w:%04x".format(wordval)
-            }
-            DataType.FLOAT -> "f:$floatval"
-            else -> "heap:$heapId"
-        }
-    }
-
-    fun numericValue(): Number {
-        return when(type) {
-            in ByteDatatypes -> byteval!!
-            in WordDatatypes -> wordval!!
-            DataType.FLOAT -> floatval!!
-            else -> throw ArithmeticException("invalid datatype for numeric value: $type")
-        }
-    }
-
-    fun integerValue(): Int {
-        return when(type) {
-            in ByteDatatypes -> byteval!!.toInt()
-            in WordDatatypes -> wordval!!
-            DataType.FLOAT -> throw ArithmeticException("float to integer loss of precision")
-            else -> throw ArithmeticException("invalid datatype for integer value: $type")
-        }
-    }
-
-    override fun hashCode(): Int {
-        val bh = byteval?.hashCode() ?: 0x10001234
-        val wh = wordval?.hashCode() ?: 0x01002345
-        val fh = floatval?.hashCode() ?: 0x00103456
-        return bh xor wh xor fh xor heapId.hashCode() xor type.hashCode()
-    }
-
-    override fun equals(other: Any?): Boolean {
-        if(other==null || other !is RuntimeValue)
-            return false
-        if(type==other.type)
-            return if (type in IterableDatatypes) heapId==other.heapId else compareTo(other)==0
-        return compareTo(other)==0      // note: datatype doesn't matter
-    }
-
-    operator fun compareTo(other: RuntimeValue): Int {
-        return if (type in NumericDatatypes && other.type in NumericDatatypes)
-            numericValue().toDouble().compareTo(other.numericValue().toDouble())
-        else throw ArithmeticException("comparison can only be done between two numeric values")
-    }
-
-    private fun arithResult(leftDt: DataType, result: Number, rightDt: DataType, op: String): RuntimeValue {
-        if(leftDt!=rightDt)
-            throw ArithmeticException("left and right datatypes are not the same")
-        if(result.toDouble() < 0 ) {
-            return when(leftDt) {
-                DataType.UBYTE, DataType.UWORD -> {
-                    // storing a negative number in an unsigned one is done by storing the 2's complement instead
-                    val number = abs(result.toDouble().toInt())
-                    if(leftDt== DataType.UBYTE)
-                        RuntimeValue(DataType.UBYTE, (number xor 255) + 1)
-                    else
-                        RuntimeValue(DataType.UWORD, (number xor 65535) + 1)
-                }
-                DataType.BYTE -> {
-                    val v=result.toInt() and 255
-                    if(v<128)
-                        RuntimeValue(DataType.BYTE, v)
-                    else
-                        RuntimeValue(DataType.BYTE, v-256)
-                }
-                DataType.WORD -> {
-                    val v=result.toInt() and 65535
-                    if(v<32768)
-                        RuntimeValue(DataType.WORD, v)
-                    else
-                        RuntimeValue(DataType.WORD, v-65536)
-                }
-                DataType.FLOAT -> RuntimeValue(DataType.FLOAT, result)
-                else -> throw ArithmeticException("$op on non-numeric type")
-            }
-        }
-
-        return when(leftDt) {
-            DataType.UBYTE -> RuntimeValue(DataType.UBYTE, result.toInt() and 255)
-            DataType.BYTE -> {
-                val v = result.toInt() and 255
-                if(v<128)
-                    RuntimeValue(DataType.BYTE, v)
-                else
-                    RuntimeValue(DataType.BYTE, v-256)
-            }
-            DataType.UWORD -> RuntimeValue(DataType.UWORD, result.toInt() and 65535)
-            DataType.WORD -> {
-                val v = result.toInt() and 65535
-                if(v<32768)
-                    RuntimeValue(DataType.WORD, v)
-                else
-                    RuntimeValue(DataType.WORD, v-65536)
-            }
-            DataType.FLOAT -> RuntimeValue(DataType.FLOAT, result)
-            else -> throw ArithmeticException("$op on non-numeric type")
-        }
-    }
-
-    fun add(other: RuntimeValue): RuntimeValue {
-        if(other.type == DataType.FLOAT && (type!= DataType.FLOAT))
-            throw ArithmeticException("floating point loss of precision on type $type")
-        val v1 = numericValue()
-        val v2 = other.numericValue()
-        val result = v1.toDouble() + v2.toDouble()
-        return arithResult(type, result, other.type, "add")
-    }
-
-    fun sub(other: RuntimeValue): RuntimeValue {
-        if(other.type == DataType.FLOAT && (type!= DataType.FLOAT))
-            throw ArithmeticException("floating point loss of precision on type $type")
-        val v1 = numericValue()
-        val v2 = other.numericValue()
-        val result = v1.toDouble() - v2.toDouble()
-        return arithResult(type, result, other.type, "sub")
-    }
-
-    fun mul(other: RuntimeValue): RuntimeValue {
-        if(other.type == DataType.FLOAT && (type!= DataType.FLOAT))
-            throw ArithmeticException("floating point loss of precision on type $type")
-        val v1 = numericValue()
-        val v2 = other.numericValue()
-        val result = v1.toDouble() * v2.toDouble()
-        return arithResult(type, result, other.type, "mul")
-    }
-
-    fun div(other: RuntimeValue): RuntimeValue {
-        if(other.type == DataType.FLOAT && (type!= DataType.FLOAT))
-            throw ArithmeticException("floating point loss of precision on type $type")
-        val v1 = numericValue()
-        val v2 = other.numericValue()
-        if(v2.toDouble()==0.0) {
-            when (type) {
-                DataType.UBYTE -> return RuntimeValue(DataType.UBYTE, 255)
-                DataType.BYTE -> return RuntimeValue(DataType.BYTE, 127)
-                DataType.UWORD -> return RuntimeValue(DataType.UWORD, 65535)
-                DataType.WORD -> return RuntimeValue(DataType.WORD, 32767)
-                else -> {}
-            }
-        }
-        val result = v1.toDouble() / v2.toDouble()
-        // NOTE: integer division returns integer result!
-        return when(type) {
-            DataType.UBYTE -> RuntimeValue(DataType.UBYTE, result)
-            DataType.BYTE -> RuntimeValue(DataType.BYTE, result)
-            DataType.UWORD -> RuntimeValue(DataType.UWORD, result)
-            DataType.WORD -> RuntimeValue(DataType.WORD, result)
-            DataType.FLOAT -> RuntimeValue(DataType.FLOAT, result)
-            else -> throw ArithmeticException("div on non-numeric type")
-        }
-    }
-
-    fun remainder(other: RuntimeValue): RuntimeValue {
-        val v1 = numericValue()
-        val v2 = other.numericValue()
-        val result = v1.toDouble() % v2.toDouble()
-        return arithResult(type, result, other.type, "remainder")
-    }
-
-    fun pow(other: RuntimeValue): RuntimeValue {
-        val v1 = numericValue()
-        val v2 = other.numericValue()
-        val result = v1.toDouble().pow(v2.toDouble())
-        return arithResult(type, result, other.type,"pow")
-    }
-
-    fun shl(): RuntimeValue {
-        val v = integerValue()
-        return when (type) {
-            DataType.UBYTE -> RuntimeValue(type, (v shl 1) and 255)
-            DataType.UWORD -> RuntimeValue(type, (v shl 1) and 65535)
-            DataType.BYTE -> {
-                val value = v shl 1
-                if(value<128)
-                    RuntimeValue(type, value)
-                else
-                    RuntimeValue(type, value-256)
-            }
-            DataType.WORD -> {
-                val value = v shl 1
-                if(value<32768)
-                    RuntimeValue(type, value)
-                else
-                    RuntimeValue(type, value-65536)
-            }
-            else -> throw ArithmeticException("invalid type for shl: $type")
-        }
-    }
-
-    fun shr(): RuntimeValue {
-        val v = integerValue()
-        return when(type){
-            DataType.UBYTE -> RuntimeValue(type, v ushr 1)
-            DataType.BYTE -> RuntimeValue(type, v shr 1)
-            DataType.UWORD -> RuntimeValue(type, v ushr 1)
-            DataType.WORD -> RuntimeValue(type, v shr 1)
-            else -> throw ArithmeticException("invalid type for shr: $type")
-        }
-    }
-
-    fun rol(carry: Boolean): Pair<RuntimeValue, Boolean> {
-        // 9 or 17 bit rotate left (with carry))
-        return when(type) {
-            DataType.UBYTE, DataType.BYTE -> {
-                val v = byteval!!.toInt()
-                val newCarry = (v and 0x80) != 0
-                val newval = (v and 0x7f shl 1) or (if(carry) 1 else 0)
-                Pair(RuntimeValue(DataType.UBYTE, newval), newCarry)
-            }
-            DataType.UWORD, DataType.WORD -> {
-                val v = wordval!!
-                val newCarry = (v and 0x8000) != 0
-                val newval = (v and 0x7fff shl 1) or (if(carry) 1 else 0)
-                Pair(RuntimeValue(DataType.UWORD, newval), newCarry)
-            }
-            else -> throw ArithmeticException("rol can only work on byte/word")
-        }
-    }
-
-    fun ror(carry: Boolean): Pair<RuntimeValue, Boolean> {
-        // 9 or 17 bit rotate right (with carry)
-        return when(type) {
-            DataType.UBYTE, DataType.BYTE -> {
-                val v = byteval!!.toInt()
-                val newCarry = v and 1 != 0
-                val newval = (v ushr 1) or (if(carry) 0x80 else 0)
-                Pair(RuntimeValue(DataType.UBYTE, newval), newCarry)
-            }
-            DataType.UWORD, DataType.WORD -> {
-                val v = wordval!!
-                val newCarry = v and 1 != 0
-                val newval = (v ushr 1) or (if(carry) 0x8000 else 0)
-                Pair(RuntimeValue(DataType.UWORD, newval), newCarry)
-            }
-            else -> throw ArithmeticException("ror2 can only work on byte/word")
-        }
-    }
-
-    fun rol2(): RuntimeValue {
-        // 8 or 16 bit rotate left
-        return when(type) {
-            DataType.UBYTE, DataType.BYTE -> {
-                val v = byteval!!.toInt()
-                val carry = (v and 0x80) ushr 7
-                val newval = (v and 0x7f shl 1) or carry
-                RuntimeValue(DataType.UBYTE, newval)
-            }
-            DataType.UWORD, DataType.WORD -> {
-                val v = wordval!!
-                val carry = (v and 0x8000) ushr 15
-                val newval = (v and 0x7fff shl 1) or carry
-                RuntimeValue(DataType.UWORD, newval)
-            }
-            else -> throw ArithmeticException("rol2 can only work on byte/word")
-        }
-    }
-
-    fun ror2(): RuntimeValue {
-        // 8 or 16 bit rotate right
-        return when(type) {
-            DataType.UBYTE, DataType.BYTE -> {
-                val v = byteval!!.toInt()
-                val carry = v and 1 shl 7
-                val newval = (v ushr 1) or carry
-                RuntimeValue(DataType.UBYTE, newval)
-            }
-            DataType.UWORD, DataType.WORD -> {
-                val v = wordval!!
-                val carry = v and 1 shl 15
-                val newval = (v ushr 1) or carry
-                RuntimeValue(DataType.UWORD, newval)
-            }
-            else -> throw ArithmeticException("ror2 can only work on byte/word")
-        }
-    }
-
-    fun neg(): RuntimeValue {
-        return when(type) {
-            DataType.BYTE -> RuntimeValue(DataType.BYTE, -(byteval!!))
-            DataType.WORD -> RuntimeValue(DataType.WORD, -(wordval!!))
-            DataType.FLOAT -> RuntimeValue(DataType.FLOAT, -(floatval)!!)
-            else -> throw ArithmeticException("neg can only work on byte/word/float")
-        }
-    }
-
-    fun abs(): RuntimeValue {
-        return when(type) {
-            DataType.BYTE -> RuntimeValue(DataType.BYTE, abs(byteval!!.toInt()))
-            DataType.WORD -> RuntimeValue(DataType.WORD, abs(wordval!!))
-            DataType.FLOAT -> RuntimeValue(DataType.FLOAT, abs(floatval!!))
-            else -> throw ArithmeticException("abs can only work on byte/word/float")
-        }
-    }
-
-    fun bitand(other: RuntimeValue): RuntimeValue {
-        val v1 = integerValue()
-        val v2 = other.integerValue()
-        val result = v1 and v2
-        return RuntimeValue(type, result)
-    }
-
-    fun bitor(other: RuntimeValue): RuntimeValue {
-        val v1 = integerValue()
-        val v2 = other.integerValue()
-        val result = v1 or v2
-        return RuntimeValue(type, result)
-    }
-
-    fun bitxor(other: RuntimeValue): RuntimeValue {
-        val v1 = integerValue()
-        val v2 = other.integerValue()
-        val result = v1 xor v2
-        return RuntimeValue(type, result)
-    }
-
-    fun and(other: RuntimeValue) = RuntimeValue(DataType.UBYTE, if (this.asBoolean && other.asBoolean) 1 else 0)
-    fun or(other: RuntimeValue) = RuntimeValue(DataType.UBYTE, if (this.asBoolean || other.asBoolean) 1 else 0)
-    fun xor(other: RuntimeValue) = RuntimeValue(DataType.UBYTE, if (this.asBoolean xor other.asBoolean) 1 else 0)
-    fun not() = RuntimeValue(DataType.UBYTE, if (this.asBoolean) 0 else 1)
-
-    fun inv(): RuntimeValue {
-        return when(type) {
-            DataType.UBYTE -> RuntimeValue(type, byteval!!.toInt().inv() and 255)
-            DataType.UWORD -> RuntimeValue(type, wordval!!.inv() and 65535)
-            DataType.BYTE -> RuntimeValue(type, byteval!!.toInt().inv())
-            DataType.WORD -> RuntimeValue(type, wordval!!.inv())
-            else -> throw ArithmeticException("inv can only work on byte/word")
-        }
-    }
-
-    fun inc(): RuntimeValue {
-        return when(type) {
-            DataType.UBYTE -> RuntimeValue(type, (byteval!! + 1) and 255)
-            DataType.UWORD -> RuntimeValue(type, (wordval!! + 1) and 65535)
-            DataType.BYTE -> {
-                val newval = byteval!! + 1
-                if(newval == 128)
-                    RuntimeValue(type, -128)
-                else
-                    RuntimeValue(type, newval)
-            }
-            DataType.WORD -> {
-                val newval = wordval!! + 1
-                if(newval == 32768)
-                    RuntimeValue(type, -32768)
-                else
-                    RuntimeValue(type, newval)
-            }
-            DataType.FLOAT -> RuntimeValue(DataType.FLOAT, floatval!! + 1)
-            else -> throw ArithmeticException("inc can only work on numeric types")
-        }
-    }
-
-    fun dec(): RuntimeValue {
-        return when(type) {
-            DataType.UBYTE -> RuntimeValue(type, (byteval!! - 1) and 255)
-            DataType.UWORD -> RuntimeValue(type, (wordval!! - 1) and 65535)
-            DataType.BYTE -> {
-                val newval = byteval!! - 1
-                if(newval == -129)
-                    RuntimeValue(type, 127)
-                else
-                    RuntimeValue(type, newval)
-            }
-            DataType.WORD -> {
-                val newval = wordval!! - 1
-                if(newval == -32769)
-                    RuntimeValue(type, 32767)
-                else
-                    RuntimeValue(type, newval)
-            }
-            DataType.FLOAT -> RuntimeValue(DataType.FLOAT, floatval!! - 1)
-            else -> throw ArithmeticException("dec can only work on numeric types")
-        }
-    }
-
-    fun msb(): RuntimeValue {
-        return when(type) {
-            in ByteDatatypes -> RuntimeValue(DataType.UBYTE, 0)
-            in WordDatatypes -> RuntimeValue(DataType.UBYTE, wordval!! ushr 8 and 255)
-            else -> throw ArithmeticException("msb can only work on (u)byte/(u)word")
-        }
-    }
-
-    fun cast(targetType: DataType): RuntimeValue {
-        return when (type) {
-            DataType.UBYTE -> {
-                when (targetType) {
-                    DataType.UBYTE -> this
-                    DataType.BYTE -> {
-                        val nval=byteval!!.toInt()
-                        if(nval<128)
-                            RuntimeValue(DataType.BYTE, nval)
-                        else
-                            RuntimeValue(DataType.BYTE, nval-256)
-                    }
-                    DataType.UWORD -> RuntimeValue(DataType.UWORD, numericValue())
-                    DataType.WORD -> {
-                        val nval = numericValue().toInt()
-                        if(nval<32768)
-                            RuntimeValue(DataType.WORD, nval)
-                        else
-                            RuntimeValue(DataType.WORD, nval-65536)
-                    }
-                    DataType.FLOAT -> RuntimeValue(DataType.FLOAT, numericValue())
-                    else -> throw ArithmeticException("invalid type cast from $type to $targetType")
-                }
-            }
-            DataType.BYTE -> {
-                when (targetType) {
-                    DataType.BYTE -> this
-                    DataType.UBYTE -> RuntimeValue(DataType.UBYTE, integerValue() and 255)
-                    DataType.UWORD -> RuntimeValue(DataType.UWORD, integerValue() and 65535)
-                    DataType.WORD -> RuntimeValue(DataType.WORD, integerValue())
-                    DataType.FLOAT -> RuntimeValue(DataType.FLOAT, numericValue())
-                    else -> throw ArithmeticException("invalid type cast from $type to $targetType")
-                }
-            }
-            DataType.UWORD -> {
-                when (targetType) {
-                    DataType.BYTE -> {
-                        val v=integerValue()
-                        if(v<128)
-                            RuntimeValue(DataType.BYTE, v)
-                        else
-                            RuntimeValue(DataType.BYTE, v-256)
-                    }
-                    DataType.UBYTE -> RuntimeValue(DataType.UBYTE, integerValue() and 255)
-                    DataType.UWORD -> this
-                    DataType.WORD -> {
-                        val v=integerValue()
-                        if(v<32768)
-                            RuntimeValue(DataType.WORD, v)
-                        else
-                            RuntimeValue(DataType.WORD, v-65536)
-                    }
-                    DataType.FLOAT -> RuntimeValue(DataType.FLOAT, numericValue())
-                    else -> throw ArithmeticException("invalid type cast from $type to $targetType")
-                }
-            }
-            DataType.WORD -> {
-                when (targetType) {
-                    DataType.BYTE -> {
-                        val v = integerValue() and 255
-                        if(v<128)
-                            RuntimeValue(DataType.BYTE, v)
-                        else
-                            RuntimeValue(DataType.BYTE, v-256)
-                    }
-                    DataType.UBYTE -> RuntimeValue(DataType.UBYTE, integerValue() and 65535)
-                    DataType.UWORD -> RuntimeValue(DataType.UWORD, integerValue())
-                    DataType.WORD -> this
-                    DataType.FLOAT -> RuntimeValue(DataType.FLOAT, numericValue())
-                    else -> throw ArithmeticException("invalid type cast from $type to $targetType")
-                }
-            }
-            DataType.FLOAT -> {
-                when (targetType) {
-                    DataType.BYTE -> {
-                        val integer=numericValue().toInt()
-                        if(integer in -128..127)
-                            RuntimeValue(DataType.BYTE, integer)
-                        else
-                            throw ArithmeticException("overflow when casting float to byte: $this")
-                    }
-                    DataType.UBYTE -> RuntimeValue(DataType.UBYTE, numericValue().toInt())
-                    DataType.UWORD -> RuntimeValue(DataType.UWORD, numericValue().toInt())
-                    DataType.WORD -> {
-                        val integer=numericValue().toInt()
-                        if(integer in -32768..32767)
-                            RuntimeValue(DataType.WORD, integer)
-                        else
-                            throw ArithmeticException("overflow when casting float to word: $this")
-                    }
-                    DataType.FLOAT -> this
-                    else -> throw ArithmeticException("invalid type cast from $type to $targetType")
-                }
-            }
-            else -> throw ArithmeticException("invalid type cast from $type to $targetType")
-        }
-    }
-
-    open fun iterator(): Iterator<Number> {
-        return when (type) {
-            in StringDatatypes -> {
-                Petscii.encodePetscii(str!!, true).iterator()
-            }
-            in ArrayDatatypes -> {
-                array!!.iterator()
-            }
-            else -> throw IllegalArgumentException("cannot iterate over $this")
-        }
-    }
-}
-
-
-class RuntimeValueRange(type: DataType, val range: IntProgression): RuntimeValue(type, array=range.toList().toTypedArray()) {
-    override fun iterator(): Iterator<Number> {
-        return range.iterator()
-    }
-}