fix chained assignment and multi-vardecl RHS evaluation

add check for memory() args to be const

.idea/kotlinc.xml

@@ -4,6 +4,6 @@
     <option name="jvmTarget" value="11" />
   </component>
   <component name="KotlinJpsPluginSettings">
-    <option name="version" value="1.9.0-release-358" />
+    <option name="version" value="1.9.20" />
   </component>
 </project>

.idea/libraries/KotlinJavaRuntime.xml

@@ -1,19 +1,26 @@
 <component name="libraryTable">
-  <library name="KotlinJavaRuntime">
-    <CLASSES>
-      <root url="jar://$KOTLIN_BUNDLED$/lib/kotlin-stdlib.jar!/" />
-      <root url="jar://$KOTLIN_BUNDLED$/lib/kotlin-reflect.jar!/" />
-      <root url="jar://$KOTLIN_BUNDLED$/lib/kotlin-test.jar!/" />
-      <root url="jar://$KOTLIN_BUNDLED$/lib/kotlin-stdlib-jdk7.jar!/" />
-      <root url="jar://$KOTLIN_BUNDLED$/lib/kotlin-stdlib-jdk8.jar!/" />
-    </CLASSES>
-    <JAVADOC />
-    <SOURCES>
-      <root url="jar://$KOTLIN_BUNDLED$/lib/kotlin-stdlib-sources.jar!/" />
-      <root url="jar://$KOTLIN_BUNDLED$/lib/kotlin-reflect-sources.jar!/" />
-      <root url="jar://$KOTLIN_BUNDLED$/lib/kotlin-test-sources.jar!/" />
-      <root url="jar://$KOTLIN_BUNDLED$/lib/kotlin-stdlib-jdk7-sources.jar!/" />
-      <root url="jar://$KOTLIN_BUNDLED$/lib/kotlin-stdlib-jdk8-sources.jar!/" />
-    </SOURCES>
-  </library>
+    <library name="KotlinJavaRuntime" type="repository">
+        <properties maven-id="org.jetbrains.kotlin:kotlin-stdlib-jdk8:1.9.0" />
+        <CLASSES>
+            <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk8/1.9.0/kotlin-stdlib-jdk8-1.9.0.jar!/" />
+            <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/1.9.0/kotlin-stdlib-1.9.0.jar!/" />
+            <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-common/1.9.0/kotlin-stdlib-common-1.9.0.jar!/" />
+            <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/annotations/13.0/annotations-13.0.jar!/" />
+            <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk7/1.9.0/kotlin-stdlib-jdk7-1.9.0.jar!/" />
+        </CLASSES>
+        <JAVADOC>
+            <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk8/1.9.0/kotlin-stdlib-jdk8-1.9.0-javadoc.jar!/" />
+            <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/1.9.0/kotlin-stdlib-1.9.0-javadoc.jar!/" />
+            <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-common/1.9.0/kotlin-stdlib-common-1.9.0-javadoc.jar!/" />
+            <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/annotations/13.0/annotations-13.0-javadoc.jar!/" />
+            <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk7/1.9.0/kotlin-stdlib-jdk7-1.9.0-javadoc.jar!/" />
+        </JAVADOC>
+        <SOURCES>
+            <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk8/1.9.0/kotlin-stdlib-jdk8-1.9.0-sources.jar!/" />
+            <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/1.9.0/kotlin-stdlib-1.9.0-sources.jar!/" />
+            <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-common/1.9.0/kotlin-stdlib-common-1.9.0-sources.jar!/" />
+            <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/annotations/13.0/annotations-13.0-sources.jar!/" />
+            <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk7/1.9.0/kotlin-stdlib-jdk7-1.9.0-sources.jar!/" />
+        </SOURCES>
+    </library>
 </component>

.idea/libraries/antlr_antlr4.xml

@@ -1,13 +1,13 @@
 <component name="libraryTable">
   <library name="antlr.antlr4" type="repository">
-    <properties maven-id="org.antlr:antlr4:4.13.0">
+    <properties maven-id="org.antlr:antlr4:4.13.1">
       <exclude>
         <dependency maven-id="com.ibm.icu:icu4j" />
       </exclude>
     </properties>
     <CLASSES>
-      <root url="jar://$MAVEN_REPOSITORY$/org/antlr/antlr4/4.13.0/antlr4-4.13.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/antlr/antlr4-runtime/4.13.0/antlr4-runtime-4.13.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/antlr/antlr4/4.13.1/antlr4-4.13.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/antlr/antlr4-runtime/4.13.1/antlr4-runtime-4.13.1.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/antlr/antlr-runtime/3.5.3/antlr-runtime-3.5.3.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/antlr/ST4/4.3.4/ST4-4.3.4.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/abego/treelayout/org.abego.treelayout.core/1.0.3/org.abego.treelayout.core-1.0.3.jar!/" />

.idea/libraries/io_kotest_assertions_core_jvm.xml

@@ -1,19 +1,19 @@
 <component name="libraryTable">
   <library name="io.kotest.assertions.core.jvm" type="repository">
-    <properties maven-id="io.kotest:kotest-assertions-core-jvm:5.6.2" />
+    <properties maven-id="io.kotest:kotest-assertions-core-jvm:5.8.0" />
     <CLASSES>
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-core-jvm/5.6.2/kotest-assertions-core-jvm-5.6.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-core-jvm/5.8.0/kotest-assertions-core-jvm-5.8.0.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk8/1.8.10/kotlin-stdlib-jdk8-1.8.10.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/1.8.10/kotlin-stdlib-1.8.10.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk7/1.8.10/kotlin-stdlib-jdk7-1.8.10.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-shared-jvm/5.6.2/kotest-assertions-shared-jvm-5.6.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-shared-jvm/5.8.0/kotest-assertions-shared-jvm-5.8.0.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/io/github/java-diff-utils/java-diff-utils/4.12/java-diff-utils-4.12.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/opentest4j/opentest4j/1.2.0/opentest4j-1.2.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/opentest4j/opentest4j/1.3.0/opentest4j-1.3.0.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-common/1.8.10/kotlin-stdlib-common-1.8.10.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-jdk8/1.7.0/kotlinx-coroutines-jdk8-1.7.0.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-reflect/1.8.10/kotlin-reflect-1.8.10.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-common-jvm/5.6.2/kotest-common-jvm-5.6.2.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-api-jvm/5.6.2/kotest-assertions-api-jvm-5.6.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-common-jvm/5.8.0/kotest-common-jvm-5.8.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-api-jvm/5.8.0/kotest-assertions-api-jvm-5.8.0.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-core-jvm/1.7.0/kotlinx-coroutines-core-jvm-1.7.0.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/annotations/23.0.0/annotations-23.0.0.jar!/" />
     </CLASSES>

.idea/libraries/io_kotest_property_jvm.xml

@@ -1,24 +0,0 @@
-<component name="libraryTable">
-  <library name="io.kotest.property.jvm" type="repository">
-    <properties maven-id="io.kotest:kotest-property-jvm:5.6.2" />
-    <CLASSES>
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-property-jvm/5.6.2/kotest-property-jvm-5.6.2.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/com/github/curious-odd-man/rgxgen/1.4/rgxgen-1.4.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk8/1.8.10/kotlin-stdlib-jdk8-1.8.10.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/1.8.10/kotlin-stdlib-1.8.10.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk7/1.8.10/kotlin-stdlib-jdk7-1.8.10.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-common-jvm/5.6.2/kotest-common-jvm-5.6.2.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-shared-jvm/5.6.2/kotest-assertions-shared-jvm-5.6.2.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-api-jvm/5.6.2/kotest-assertions-api-jvm-5.6.2.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-jdk8/1.7.0/kotlinx-coroutines-jdk8-1.7.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/opentest4j/opentest4j/1.2.0/opentest4j-1.2.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-common/1.8.10/kotlin-stdlib-common-1.8.10.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/github/java-diff-utils/java-diff-utils/4.12/java-diff-utils-4.12.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-reflect/1.8.10/kotlin-reflect-1.8.10.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-core-jvm/1.7.0/kotlinx-coroutines-core-jvm-1.7.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/annotations/23.0.0/annotations-23.0.0.jar!/" />
-    </CLASSES>
-    <JAVADOC />
-    <SOURCES />
-  </library>
-</component>

.idea/libraries/io_kotest_runner_junit5_jvm.xml

@@ -1,29 +1,29 @@
 <component name="libraryTable">
   <library name="io.kotest.runner.junit5.jvm" type="repository">
-    <properties maven-id="io.kotest:kotest-runner-junit5-jvm:5.6.2" />
+    <properties maven-id="io.kotest:kotest-runner-junit5-jvm:5.8.0" />
     <CLASSES>
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-runner-junit5-jvm/5.6.2/kotest-runner-junit5-jvm-5.6.2.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-framework-api-jvm/5.6.2/kotest-framework-api-jvm-5.6.2.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-shared-jvm/5.6.2/kotest-assertions-shared-jvm-5.6.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-runner-junit5-jvm/5.8.0/kotest-runner-junit5-jvm-5.8.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-framework-api-jvm/5.8.0/kotest-framework-api-jvm-5.8.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-shared-jvm/5.8.0/kotest-assertions-shared-jvm-5.8.0.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/io/github/java-diff-utils/java-diff-utils/4.12/java-diff-utils-4.12.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-test-jvm/1.7.0/kotlinx-coroutines-test-jvm-1.7.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-common-jvm/5.6.2/kotest-common-jvm-5.6.2.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-framework-engine-jvm/5.6.2/kotest-framework-engine-jvm-5.6.2.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/github/classgraph/classgraph/4.8.157/classgraph-4.8.157.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-common-jvm/5.8.0/kotest-common-jvm-5.8.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-framework-engine-jvm/5.8.0/kotest-framework-engine-jvm-5.8.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/github/classgraph/classgraph/4.8.162/classgraph-4.8.162.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/com/github/ajalt/mordant/1.2.1/mordant-1.2.1.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/com/github/ajalt/colormath/1.2.0/colormath-1.2.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/opentest4j/opentest4j/1.2.0/opentest4j-1.2.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/opentest4j/opentest4j/1.3.0/opentest4j-1.3.0.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-debug/1.7.0/kotlinx-coroutines-debug-1.7.0.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/net/java/dev/jna/jna/5.9.0/jna-5.9.0.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/net/java/dev/jna/jna-platform/5.9.0/jna-platform-5.9.0.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/net/bytebuddy/byte-buddy/1.10.9/byte-buddy-1.10.9.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/net/bytebuddy/byte-buddy-agent/1.10.9/byte-buddy-agent-1.10.9.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-framework-discovery-jvm/5.6.2/kotest-framework-discovery-jvm-5.6.2.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-core-jvm/5.6.2/kotest-assertions-core-jvm-5.6.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-framework-discovery-jvm/5.8.0/kotest-framework-discovery-jvm-5.8.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-core-jvm/5.8.0/kotest-assertions-core-jvm-5.8.0.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-jdk8/1.7.0/kotlinx-coroutines-jdk8-1.7.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-api-jvm/5.6.2/kotest-assertions-api-jvm-5.6.2.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-extensions-jvm/5.6.2/kotest-extensions-jvm-5.6.2.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-framework-concurrency-jvm/5.6.2/kotest-framework-concurrency-jvm-5.6.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-api-jvm/5.8.0/kotest-assertions-api-jvm-5.8.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-extensions-jvm/5.8.0/kotest-extensions-jvm-5.8.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-framework-concurrency-jvm/5.8.0/kotest-framework-concurrency-jvm-5.8.0.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-core-jvm/1.7.0/kotlinx-coroutines-core-jvm-1.7.0.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/annotations/23.0.0/annotations-23.0.0.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/junit/platform/junit-platform-engine/1.8.2/junit-platform-engine-1.8.2.jar!/" />

.idea/libraries/jetbrains_kotlinx_cli_jvm.xml

@@ -1,8 +1,8 @@
 <component name="libraryTable">
   <library name="jetbrains.kotlinx.cli.jvm" type="repository">
-    <properties include-transitive-deps="false" maven-id="org.jetbrains.kotlinx:kotlinx-cli-jvm:0.3.5" />
+    <properties include-transitive-deps="false" maven-id="org.jetbrains.kotlinx:kotlinx-cli-jvm:0.3.6" />
     <CLASSES>
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-cli-jvm/0.3.5/kotlinx-cli-jvm-0.3.5.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-cli-jvm/0.3.6/kotlinx-cli-jvm-0.3.6.jar!/" />
     </CLASSES>
     <JAVADOC />
     <SOURCES />

.idea/libraries/slf4j_simple.xml

@@ -1,9 +1,9 @@
 <component name="libraryTable">
   <library name="slf4j.simple" type="repository">
-    <properties maven-id="org.slf4j:slf4j-simple:2.0.7" />
+    <properties maven-id="org.slf4j:slf4j-simple:2.0.9" />
     <CLASSES>
-      <root url="jar://$MAVEN_REPOSITORY$/org/slf4j/slf4j-simple/2.0.7/slf4j-simple-2.0.7.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/slf4j/slf4j-api/2.0.7/slf4j-api-2.0.7.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/slf4j/slf4j-simple/2.0.9/slf4j-simple-2.0.9.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/slf4j/slf4j-api/2.0.9/slf4j-api-2.0.9.jar!/" />
     </CLASSES>
     <JAVADOC />
     <SOURCES />

.idea/misc.xml

@@ -16,6 +16,9 @@
       </list>
     </option>
   </component>
+  <component name="Black">
+    <option name="sdkName" value="Python 3.11" />
+  </component>
   <component name="FrameworkDetectionExcludesConfiguration">
     <type id="Python" />
   </component>

README.md

@@ -74,6 +74,8 @@ What does Prog8 provide?
 - "c64": Commodore-64  (6502 like CPU)
 - "c128": Commodore-128  (6502 like CPU - the Z80 cpu mode is not supported)
 - "cx16": [CommanderX16](https://www.commanderx16.com)  (65c02 CPU)
+- "pet32": Commodore PET (experimental)
+- "atari": Atari 8 bit such as 800XL (experimental)
 - If you only use standard kernal and prog8 library routines, it is possible to compile the *exact same program* for different machines (just change the compiler target flag)
 
 

codeCore/build.gradle

@@ -32,10 +32,10 @@ dependencies {
 sourceSets {
     main {
         java {
-            srcDirs = ["${project.projectDir}/src"]
+            srcDir "${project.projectDir}/src"
         }
         resources {
-            srcDirs = ["${project.projectDir}/res"]
+            srcDir "${project.projectDir}/res"
         }
     }
 }

codeCore/src/prog8/code/SymbolTable.kt

@@ -196,13 +196,10 @@ class StStaticVariable(name: String,
         }
         if(onetimeInitializationNumericValue!=null) {
             require(dt in NumericDatatypes)
-            require(onetimeInitializationNumericValue!=0.0) { "zero as init value should just remain uninitialized"}
         }
         if(onetimeInitializationArrayValue!=null) {
             require(dt in ArrayDatatypes)
-            if(onetimeInitializationArrayValue.all { it.number!=null} ) {
-                require(onetimeInitializationArrayValue.any { it.number != 0.0 }) { "array of all zerors as init value should just remain uninitialized" }
-            }
+            require(length==onetimeInitializationArrayValue.size)
         }
         if(onetimeInitializationStringValue!=null) {
             require(dt == DataType.STR)
@@ -213,8 +210,7 @@ class StStaticVariable(name: String,
 
 
 class StConstant(name: String, val dt: DataType, val value: Double, astNode: PtNode) :
-    StNode(name, StNodeType.CONSTANT, astNode) {
-}
+    StNode(name, StNodeType.CONSTANT, astNode)
 
 
 class StMemVar(name: String,
@@ -236,12 +232,11 @@ class StMemorySlab(
     val align: UInt,
     astNode: PtNode
 ):
-    StNode(name, StNodeType.MEMORYSLAB, astNode) {
-}
+    StNode(name, StNodeType.MEMORYSLAB, astNode)
+
 
 class StSub(name: String, val parameters: List<StSubroutineParameter>, val returnType: DataType?, astNode: PtNode) :
-        StNode(name, StNodeType.SUBROUTINE, astNode) {
-}
+        StNode(name, StNodeType.SUBROUTINE, astNode)
 
 
 class StRomSub(name: String,

codeCore/src/prog8/code/SymbolTableMaker.kt

@@ -26,8 +26,6 @@ class SymbolTableMaker(private val program: PtProgram, private val options: Comp
                 PtMemMapped("P8ZP_SCRATCH_REG", DataType.UBYTE, options.compTarget.machine.zeropage.SCRATCH_REG, null, Position.DUMMY),
                 PtMemMapped("P8ZP_SCRATCH_W1", DataType.UWORD, options.compTarget.machine.zeropage.SCRATCH_W1, null, Position.DUMMY),
                 PtMemMapped("P8ZP_SCRATCH_W2", DataType.UWORD, options.compTarget.machine.zeropage.SCRATCH_W2, null, Position.DUMMY),
-                PtMemMapped("P8ESTACK_LO", DataType.ARRAY_UB, options.compTarget.machine.ESTACK_LO, 128u, Position.DUMMY),
-                PtMemMapped("P8ESTACK_HI", DataType.ARRAY_UB, options.compTarget.machine.ESTACK_HI, 128u, Position.DUMMY)
             ).forEach {
                 it.parent = program
                 st.add(StMemVar(it.name, it.type, it.address, it.arraySize?.toInt(), it))
@@ -76,10 +74,9 @@ class SymbolTableMaker(private val program: PtProgram, private val options: Comp
                             numElements = value.value.length + 1   // include the terminating 0-byte
                         }
                         is PtArray -> {
-                            val array = makeInitialArray(value)
-                            initialArray = if(array.all { it.number==0.0 }) null else array            // all 0 as init value -> just uninitialized
+                            initialArray = makeInitialArray(value)
                             initialString = null
-                            numElements = array.size
+                            numElements = initialArray.size
                             require(node.arraySize?.toInt()==numElements)
                         }
                         else -> {
@@ -128,7 +125,11 @@ class SymbolTableMaker(private val program: PtProgram, private val options: Comp
     private fun makeInitialArray(value: PtArray): List<StArrayElement> {
         return value.children.map {
             when(it) {
-                is PtAddressOf -> StArrayElement(null, it.identifier.name)
+                is PtAddressOf -> {
+                    if(it.isFromArrayElement)
+                        TODO("address-of array element $it in initial array value")
+                    StArrayElement(null, it.identifier.name)
+                }
                 is PtIdentifier -> StArrayElement(null, it.name)
                 is PtNumber -> StArrayElement(it.number, null)
                 else -> throw AssemblyError("invalid array element $it")

codeCore/src/prog8/code/ast/AstBase.kt

@@ -75,6 +75,7 @@ class PtBlock(name: String,
               val library: Boolean,
               val forceOutput: Boolean,
               val noSymbolPrefixing: Boolean,
+              val veraFxMuls: Boolean,
               val alignment: BlockAlignment,
               val source: SourceCode,       // taken from the module the block is defined in.
               position: Position

codeCore/src/prog8/code/ast/AstExpressions.kt

@@ -24,7 +24,17 @@ sealed class PtExpression(val type: DataType, position: Position) : PtNode(posit
 
     infix fun isSameAs(other: PtExpression): Boolean {
         return when(this) {
-            is PtAddressOf -> other is PtAddressOf && other.type==type && other.identifier isSameAs identifier
+            is PtAddressOf -> {
+                if(other !is PtAddressOf)
+                    return false
+                if (other.type!==type || !(other.identifier isSameAs identifier))
+                    return false
+                if(other.children.size!=children.size)
+                    return false
+                if(children.size==1)
+                    return true
+                return arrayIndexExpr!! isSameAs other.arrayIndexExpr!!
+            }
             is PtArrayIndexer -> other is PtArrayIndexer && other.type==type && other.variable isSameAs variable && other.index isSameAs index && other.splitWords==splitWords
             is PtBinaryExpression -> other is PtBinaryExpression && other.left isSameAs left && other.right isSameAs right
             is PtContainmentCheck -> other is PtContainmentCheck && other.type==type && other.element isSameAs element && other.iterable isSameAs iterable
@@ -105,7 +115,12 @@ sealed class PtExpression(val type: DataType, position: Position) : PtNode(posit
 
 class PtAddressOf(position: Position) : PtExpression(DataType.UWORD, position) {
     val identifier: PtIdentifier
-        get() = children.single() as PtIdentifier
+        get() = children[0] as PtIdentifier
+    val arrayIndexExpr: PtExpression?
+        get() = if(children.size==2) children[1] as PtExpression else null
+
+    val isFromArrayElement: Boolean
+        get() = children.size==2
 }
 
 
@@ -118,6 +133,9 @@ class PtArrayIndexer(elementType: DataType, position: Position): PtExpression(el
     val splitWords: Boolean
         get() = variable.type in SplitWordArrayTypes
 
+    val usesPointerVariable: Boolean
+        get() = variable.type==DataType.UWORD
+
     init {
         require(elementType in NumericDatatypes)
     }

codeCore/src/prog8/code/ast/AstPrinter.kt

@@ -126,7 +126,6 @@ fun printAst(root: PtNode, skipLibraries: Boolean, output: (text: String) -> Uni
                 else
                     "->"
             }
-            else -> throw InternalCompilerException("unrecognised ast node $node")
         }
     }
 

codeCore/src/prog8/code/core/BuiltinFunctions.kt

@@ -70,6 +70,8 @@ class FSignature(val pure: Boolean,      // does it have side effects?
 
 val BuiltinFunctions: Map<String, FSignature> = mapOf(
     // this set of function have no return value and operate in-place:
+    "setlsb"    to FSignature(false, listOf(FParam("variable", arrayOf(DataType.WORD, DataType.UWORD)), FParam("value", arrayOf(DataType.BYTE, DataType.UBYTE))), null),
+    "setmsb"    to FSignature(false, listOf(FParam("variable", arrayOf(DataType.WORD, DataType.UWORD)), FParam("value", arrayOf(DataType.BYTE, DataType.UBYTE))), null),
     "rol"       to FSignature(false, listOf(FParam("item", arrayOf(DataType.UBYTE, DataType.UWORD))), null),
     "ror"       to FSignature(false, listOf(FParam("item", arrayOf(DataType.UBYTE, DataType.UWORD))), null),
     "rol2"      to FSignature(false, listOf(FParam("item", arrayOf(DataType.UBYTE, DataType.UWORD))), null),
@@ -78,7 +80,9 @@ val BuiltinFunctions: Map<String, FSignature> = mapOf(
     "reverse"   to FSignature(false, listOf(FParam("array", ArrayDatatypes)), null),
     // cmp returns a status in the carry flag, but not a proper return value
     "cmp"       to FSignature(false, listOf(FParam("value1", IntegerDatatypesNoBool), FParam("value2", NumericDatatypesNoBool)), null),
-    "prog8_lib_stringcompare"       to FSignature(true, listOf(FParam("str1", arrayOf(DataType.STR)), FParam("str2", arrayOf(DataType.STR))), DataType.BYTE),
+    "prog8_lib_stringcompare"     to FSignature(true, listOf(FParam("str1", arrayOf(DataType.STR)), FParam("str2", arrayOf(DataType.STR))), DataType.BYTE),
+    "prog8_lib_square_byte"       to FSignature(true, listOf(FParam("value", arrayOf(DataType.BYTE, DataType.UBYTE))), DataType.UBYTE),
+    "prog8_lib_square_word"       to FSignature(true, listOf(FParam("value", arrayOf(DataType.WORD, DataType.UWORD))), DataType.UWORD),
     "abs"       to FSignature(true, listOf(FParam("value", NumericDatatypesNoBool)), null),
     "abs__byte"  to FSignature(true, listOf(FParam("value", arrayOf(DataType.BYTE))), DataType.BYTE),
     "abs__word"  to FSignature(true, listOf(FParam("value", arrayOf(DataType.WORD))), DataType.WORD),
@@ -116,19 +120,19 @@ val BuiltinFunctions: Map<String, FSignature> = mapOf(
     "max__uword" to FSignature(true, listOf(FParam("val1", arrayOf(DataType.UWORD)), FParam("val2", arrayOf(DataType.UWORD))), DataType.UWORD),
     "peek"      to FSignature(true, listOf(FParam("address", arrayOf(DataType.UWORD))), DataType.UBYTE),
     "peekw"     to FSignature(true, listOf(FParam("address", arrayOf(DataType.UWORD))), DataType.UWORD),
+    "peekf"     to FSignature(true, listOf(FParam("address", arrayOf(DataType.UWORD))), DataType.FLOAT),
     "poke"      to FSignature(false, listOf(FParam("address", arrayOf(DataType.UWORD)), FParam("value", arrayOf(DataType.UBYTE))), null),
-    "pokemon"   to FSignature(false, listOf(FParam("address", arrayOf(DataType.UWORD)), FParam("value", arrayOf(DataType.UBYTE))), null),
     "pokew"     to FSignature(false, listOf(FParam("address", arrayOf(DataType.UWORD)), FParam("value", arrayOf(DataType.UWORD))), null),
+    "pokef"     to FSignature(false, listOf(FParam("address", arrayOf(DataType.UWORD)), FParam("value", arrayOf(DataType.FLOAT))), null),
+    "pokemon"   to FSignature(false, listOf(FParam("address", arrayOf(DataType.UWORD)), FParam("value", arrayOf(DataType.UBYTE))), DataType.UBYTE),
     "pop"       to FSignature(false, listOf(FParam("target", ByteDatatypes)), null),
     "popw"      to FSignature(false, listOf(FParam("target", WordDatatypes)), null),
     "push"      to FSignature(false, listOf(FParam("value", ByteDatatypes)), null),
     "pushw"     to FSignature(false, listOf(FParam("value", WordDatatypes)), null),
     "rsave"     to FSignature(false, emptyList(), null),
-    "rsavex"    to FSignature(false, emptyList(), null),
     "rrestore"  to FSignature(false, emptyList(), null),
-    "rrestorex" to FSignature(false, emptyList(), null),
     "memory"    to FSignature(true, listOf(FParam("name", arrayOf(DataType.STR)), FParam("size", arrayOf(DataType.UWORD)), FParam("alignment", arrayOf(DataType.UWORD))), DataType.UWORD),
     "callfar"   to FSignature(false, listOf(FParam("bank", arrayOf(DataType.UBYTE)), FParam("address", arrayOf(DataType.UWORD)), FParam("arg", arrayOf(DataType.UWORD))), DataType.UWORD),
 )
 
-val InplaceModifyingBuiltinFunctions = setOf("rol", "ror", "rol2", "ror2", "sort", "reverse")
+val InplaceModifyingBuiltinFunctions = setOf("setlsb", "setmsb", "rol", "ror", "rol2", "ror2", "sort", "reverse")

codeCore/src/prog8/code/core/CompilationOptions.kt

@@ -8,24 +8,29 @@ class CompilationOptions(val output: OutputType,
                          val launcher: CbmPrgLauncherType,
                          val zeropage: ZeropageType,
                          val zpReserved: List<UIntRange>,
+                         val zpAllowed: List<UIntRange>,
                          val floats: Boolean,
                          val noSysInit: Boolean,
                          val compTarget: ICompilationTarget,
                          // these are set later, based on command line arguments or options in the source code:
                          var loadAddress: UInt,
-                         var slowCodegenWarnings: Boolean = false,
+                         var warnSymbolShadowing: Boolean = false,
                          var optimize: Boolean = false,
-                         var optimizeFloatExpressions: Boolean = false,
                          var asmQuiet: Boolean = false,
                          var asmListfile: Boolean = false,
+                         var includeSourcelines: Boolean = false,
                          var experimentalCodegen: Boolean = false,
                          var varsHighBank: Int? = null,
                          var splitWordArrays: Boolean = false,
-                         var evalStackBaseAddress: UInt? = null,
+                         var breakpointCpuInstruction: Boolean = false,
                          var outputDir: Path = Path(""),
                          var symbolDefs: Map<String, String> = emptyMap()
 ) {
     init {
         compTarget.machine.initializeMemoryAreas(this)
     }
+
+    companion object {
+        val AllZeropageAllowed: List<UIntRange> = listOf(0u..255u)
+    }
 }

codeCore/src/prog8/code/core/Enumerations.kt

@@ -1,12 +1,13 @@
 package prog8.code.core
 
 enum class DataType {
-    UBYTE,              // pass by value
-    BYTE,               // pass by value
-    UWORD,              // pass by value
-    WORD,               // pass by value
-    FLOAT,              // pass by value
-    BOOL,               // pass by value
+    UBYTE,              // pass by value            8 bits unsigned
+    BYTE,               // pass by value            8 bits signed
+    UWORD,              // pass by value            16 bits unsigned
+    WORD,               // pass by value            16 bits signed
+    LONG,               // pass by value            32 bits signed
+    FLOAT,              // pass by value            machine dependent
+    BOOL,               // pass by value            bit 0 of a 8 bit byte
     STR,                // pass by reference
     ARRAY_UB,           // pass by reference
     ARRAY_B,            // pass by reference
@@ -23,11 +24,12 @@ enum class DataType {
      */
     infix fun isAssignableTo(targetType: DataType) =
         when(this) {
-            BOOL -> targetType.oneOf(BOOL, BYTE, UBYTE, WORD, UWORD, FLOAT)
-            UBYTE -> targetType.oneOf(UBYTE, WORD, UWORD, FLOAT, BOOL)
-            BYTE -> targetType.oneOf(BYTE, WORD, FLOAT)
-            UWORD -> targetType.oneOf(UWORD, FLOAT)
-            WORD -> targetType.oneOf(WORD, FLOAT)
+            BOOL -> targetType.oneOf(BOOL, BYTE, UBYTE, WORD, UWORD, LONG, FLOAT)
+            UBYTE -> targetType.oneOf(UBYTE, WORD, UWORD, LONG, FLOAT, BOOL)
+            BYTE -> targetType.oneOf(BYTE, WORD, LONG, FLOAT)
+            UWORD -> targetType.oneOf(UWORD, LONG, FLOAT)
+            WORD -> targetType.oneOf(WORD, LONG, FLOAT)
+            LONG -> targetType.oneOf(LONG, FLOAT)
             FLOAT -> targetType.oneOf(FLOAT)
             STR -> targetType.oneOf(STR, UWORD)
             in ArrayDatatypes -> targetType == this
@@ -41,7 +43,8 @@ enum class DataType {
             this == other -> false
             this in ByteDatatypes -> false
             this in WordDatatypes -> other in ByteDatatypes
-            this== STR && other== UWORD || this== UWORD && other== STR -> false
+            this == LONG -> other in ByteDatatypes+WordDatatypes
+            this == STR && other == UWORD || this == UWORD && other == STR -> false
             else -> true
         }
 
@@ -76,6 +79,13 @@ enum class RegisterOrPair {
 
     companion object {
         val names by lazy { values().map { it.toString()} }
+        fun fromCpuRegister(cpu: CpuRegister): RegisterOrPair {
+            return when(cpu) {
+                CpuRegister.A -> A
+                CpuRegister.X -> X
+                CpuRegister.Y -> Y
+            }
+        }
     }
 
     fun asCpuRegister(): CpuRegister = when(this) {
@@ -116,11 +126,11 @@ enum class BranchCondition {
 
 val ByteDatatypes = arrayOf(DataType.UBYTE, DataType.BYTE, DataType.BOOL)
 val WordDatatypes = arrayOf(DataType.UWORD, DataType.WORD)
-val IntegerDatatypes = arrayOf(DataType.UBYTE, DataType.BYTE, DataType.UWORD, DataType.WORD, DataType.BOOL)
-val IntegerDatatypesNoBool = arrayOf(DataType.UBYTE, DataType.BYTE, DataType.UWORD, DataType.WORD)
-val NumericDatatypes = arrayOf(DataType.UBYTE, DataType.BYTE, DataType.UWORD, DataType.WORD, DataType.FLOAT, DataType.BOOL)
-val NumericDatatypesNoBool = arrayOf(DataType.UBYTE, DataType.BYTE, DataType.UWORD, DataType.WORD, DataType.FLOAT)
-val SignedDatatypes =  arrayOf(DataType.BYTE, DataType.WORD, DataType.FLOAT)
+val IntegerDatatypesNoBool = arrayOf(DataType.UBYTE, DataType.BYTE, DataType.UWORD, DataType.WORD, DataType.LONG)
+val IntegerDatatypes = IntegerDatatypesNoBool + DataType.BOOL
+val NumericDatatypesNoBool = arrayOf(DataType.UBYTE, DataType.BYTE, DataType.UWORD, DataType.WORD, DataType.LONG, DataType.FLOAT)
+val NumericDatatypes = NumericDatatypesNoBool + DataType.BOOL
+val SignedDatatypes =  arrayOf(DataType.BYTE, DataType.WORD, DataType.LONG, DataType.FLOAT)
 val ArrayDatatypes = arrayOf(DataType.ARRAY_UB, DataType.ARRAY_B, DataType.ARRAY_UW, DataType.ARRAY_UW_SPLIT, DataType.ARRAY_W, DataType.ARRAY_W_SPLIT, DataType.ARRAY_F, DataType.ARRAY_BOOL)
 val StringlyDatatypes = arrayOf(DataType.STR, DataType.ARRAY_UB, DataType.ARRAY_B, DataType.UWORD)
 val SplitWordArrayTypes = arrayOf(DataType.ARRAY_UW_SPLIT, DataType.ARRAY_W_SPLIT)
@@ -152,6 +162,7 @@ val ElementToArrayTypes = mapOf(
     DataType.FLOAT to DataType.ARRAY_F,
     DataType.BOOL to DataType.ARRAY_BOOL
 )
+
 val Cx16VirtualRegisters = arrayOf(
     RegisterOrPair.R0, RegisterOrPair.R1, RegisterOrPair.R2, RegisterOrPair.R3,
     RegisterOrPair.R4, RegisterOrPair.R5, RegisterOrPair.R6, RegisterOrPair.R7,
@@ -159,6 +170,10 @@ val Cx16VirtualRegisters = arrayOf(
     RegisterOrPair.R12, RegisterOrPair.R13, RegisterOrPair.R14, RegisterOrPair.R15
 )
 
+val CpuRegisters = setOf(
+    RegisterOrPair.A, RegisterOrPair.X, RegisterOrPair.Y,
+    RegisterOrPair.AX, RegisterOrPair.AY, RegisterOrPair.XY
+)
 
 
 enum class OutputType {

codeCore/src/prog8/code/core/ICompilationTarget.kt

@@ -3,8 +3,6 @@ package prog8.code.core
 interface ICompilationTarget: IStringEncoding, IMemSizer {
     val name: String
     val machine: IMachineDefinition
-    val supportedEncodings: Set<Encoding>
-    val defaultEncoding: Encoding
 
     override fun encodeString(str: String, encoding: Encoding): List<UByte>
     override fun decodeString(bytes: Iterable<UByte>, encoding: Encoding): String

codeCore/src/prog8/code/core/IMachineDefinition.kt

@@ -13,8 +13,6 @@ interface IMachineDefinition {
     val FLOAT_MAX_NEGATIVE: Double
     val FLOAT_MAX_POSITIVE: Double
     val FLOAT_MEM_SIZE: Int
-    var ESTACK_LO: UInt
-    var ESTACK_HI: UInt
     val PROGRAM_LOAD_ADDRESS : UInt
     val BSSHIGHRAM_START: UInt
     val BSSHIGHRAM_END: UInt
@@ -29,11 +27,4 @@ interface IMachineDefinition {
     fun importLibs(compilerOptions: CompilationOptions, compilationTargetName: String): List<String>
     fun launchEmulator(selectedEmulator: Int, programNameWithPath: Path)
     fun isIOAddress(address: UInt): Boolean
-    fun overrideEvalStack(evalStackBaseAddress: UInt) {
-        require(evalStackBaseAddress and 255u == 0u)
-        ESTACK_LO = evalStackBaseAddress
-        ESTACK_HI = evalStackBaseAddress + 256u
-        require(ESTACK_LO !in golden.region && ESTACK_HI !in golden.region) { "user-set ESTACK can't be in GOLDEN ram" }
-    }
-
 }

codeCore/src/prog8/code/core/IStringEncoding.kt

@@ -9,6 +9,8 @@ enum class Encoding(val prefix: String) {
 }
 
 interface IStringEncoding {
+    val defaultEncoding: Encoding
+
     fun encodeString(str: String, encoding: Encoding): List<UByte>
     fun decodeString(bytes: Iterable<UByte>, encoding: Encoding): String
 }

codeCore/src/prog8/code/core/MemoryRegions.kt

@@ -42,6 +42,13 @@ abstract class Zeropage(options: CompilationOptions): MemoryAllocator(options) {
         }
     }
 
+    fun retainAllowed() {
+        synchronized(this) {
+            for(allowed in options.zpAllowed)
+                free.retainAll { it in allowed }
+        }
+    }
+
     fun availableBytes() = if(options.zeropage== ZeropageType.DONTUSE) 0 else free.size
     fun hasByteAvailable() = if(options.zeropage== ZeropageType.DONTUSE) false else free.isNotEmpty()
     fun hasWordAvailable(): Boolean {

codeCore/src/prog8/code/core/Position.kt

@@ -1,6 +1,6 @@
 package prog8.code.core
 
-import prog8.code.core.SourceCode.Companion.libraryFilePrefix
+import prog8.code.core.SourceCode.Companion.LIBRARYFILEPREFIX
 import java.nio.file.InvalidPathException
 import kotlin.io.path.Path
 import kotlin.io.path.absolute
@@ -10,7 +10,7 @@ data class Position(val file: String, val line: Int, val startCol: Int, val endC
     fun toClickableStr(): String {
         if(this===DUMMY)
             return ""
-        if(file.startsWith(libraryFilePrefix))
+        if(file.startsWith(LIBRARYFILEPREFIX))
             return "$file:$line:$startCol:"
         return try {
             val path = Path(file).absolute().normalize().toString()

codeCore/src/prog8/code/core/SourceCode.kt

@@ -3,6 +3,7 @@ package prog8.code.core
 import java.io.File
 import java.io.IOException
 import java.nio.file.Path
+import java.text.Normalizer
 import kotlin.io.path.Path
 import kotlin.io.path.readText
 
@@ -54,12 +55,14 @@ sealed class SourceCode {
         /**
          * filename prefix to designate library files that will be retreived from internal resources rather than disk
          */
-        const val libraryFilePrefix = "library:"
-        const val stringSourcePrefix = "string:"
+        const val LIBRARYFILEPREFIX = "library:"
+        const val STRINGSOURCEPREFIX = "string:"
         val curdir: Path = Path(".").toAbsolutePath()
         fun relative(path: Path): Path = curdir.relativize(path.toAbsolutePath())
         fun isRegularFilesystemPath(pathString: String) =
-            !(pathString.startsWith(libraryFilePrefix) || pathString.startsWith(stringSourcePrefix))
+            !(pathString.startsWith(LIBRARYFILEPREFIX) || pathString.startsWith(STRINGSOURCEPREFIX))
+
+        fun isLibraryResource(path: String) = path.startsWith(LIBRARYFILEPREFIX)
     }
 
     /**
@@ -69,7 +72,7 @@ sealed class SourceCode {
     class Text(override val text: String): SourceCode() {
         override val isFromResources = false
         override val isFromFilesystem = false
-        override val origin = "$stringSourcePrefix${System.identityHashCode(text).toString(16)}"
+        override val origin = "$STRINGSOURCEPREFIX${System.identityHashCode(text).toString(16)}"
         override val name = "<unnamed-text>"
     }
 
@@ -92,7 +95,7 @@ sealed class SourceCode {
             val normalized = path.normalize()
             origin = relative(normalized).toString()
             try {
-                text = normalized.readText()
+                text = Normalizer.normalize(normalized.readText(), Normalizer.Form.NFC)
                 name = normalized.toFile().nameWithoutExtension
             } catch (nfx: java.nio.file.NoSuchFileException) {
                 throw NoSuchFileException(normalized.toFile()).also { it.initCause(nfx) }
@@ -110,7 +113,7 @@ sealed class SourceCode {
 
         override val isFromResources = true
         override val isFromFilesystem = false
-        override val origin = "$libraryFilePrefix$normalized"
+        override val origin = "$LIBRARYFILEPREFIX$normalized"
         override val text: String
         override val name: String
 
@@ -124,7 +127,7 @@ sealed class SourceCode {
                 )
             }
             val stream = object {}.javaClass.getResourceAsStream(normalized)
-            text = stream!!.reader().use { it.readText() }
+            text = stream!!.reader().use { Normalizer.normalize(it.readText(), Normalizer.Form.NFC) }
             name = Path(pathString).toFile().nameWithoutExtension
         }
     }
@@ -139,3 +142,33 @@ sealed class SourceCode {
         override val text: String = "<generated code node, no text representation>"
     }
 }
+
+
+object SourceLineCache {
+    private val cache = mutableMapOf<String, List<String>>()
+
+    private fun getCachedFile(file: String): List<String> {
+        val existing = cache[file]
+        if(existing!=null)
+            return existing
+        if (SourceCode.isRegularFilesystemPath(file)) {
+            val source = SourceCode.File(Path(file))
+            cache[file] = source.text.split('\n', '\r').map { it.trim() }
+            return cache.getValue(file)
+        } else if(file.startsWith(SourceCode.LIBRARYFILEPREFIX)) {
+            val source = SourceCode.Resource(file.drop(SourceCode.LIBRARYFILEPREFIX.length))
+            cache[file] = source.text.split('\n', '\r').map { it.trim()}
+            return cache.getValue(file)
+        }
+        return emptyList()
+    }
+
+    fun retrieveLine(position: Position): String? {
+        if (position.line>0) {
+            val lines = getCachedFile(position.file)
+            if(lines.isNotEmpty())
+                return lines[position.line-1]
+        }
+        return null
+    }
+}

codeCore/src/prog8/code/target/AtariTarget.kt

@@ -7,7 +7,6 @@ import prog8.code.target.atari.AtariMachineDefinition
 class AtariTarget: ICompilationTarget, IStringEncoding by Encoder, IMemSizer {
     override val name = NAME
     override val machine = AtariMachineDefinition()
-    override val supportedEncodings = setOf(Encoding.ATASCII)
     override val defaultEncoding = Encoding.ATASCII
 
     companion object {

codeCore/src/prog8/code/target/C128Target.kt

@@ -11,7 +11,6 @@ import prog8.code.target.cbm.CbmMemorySizer
 class C128Target: ICompilationTarget, IStringEncoding by Encoder, IMemSizer by CbmMemorySizer {
     override val name = NAME
     override val machine = C128MachineDefinition()
-    override val supportedEncodings = setOf(Encoding.PETSCII, Encoding.SCREENCODES)
     override val defaultEncoding = Encoding.PETSCII
 
     companion object {

codeCore/src/prog8/code/target/C64Target.kt

@@ -11,7 +11,6 @@ import prog8.code.target.cbm.CbmMemorySizer
 class C64Target: ICompilationTarget, IStringEncoding by Encoder, IMemSizer by CbmMemorySizer {
     override val name = NAME
     override val machine = C64MachineDefinition()
-    override val supportedEncodings = setOf(Encoding.PETSCII, Encoding.SCREENCODES)
     override val defaultEncoding = Encoding.PETSCII
 
     companion object {

codeCore/src/prog8/code/target/Cx16Target.kt

@@ -11,7 +11,6 @@ import prog8.code.target.cx16.CX16MachineDefinition
 class Cx16Target: ICompilationTarget, IStringEncoding by Encoder, IMemSizer by CbmMemorySizer {
     override val name = NAME
     override val machine = CX16MachineDefinition()
-    override val supportedEncodings = setOf(Encoding.PETSCII, Encoding.SCREENCODES, Encoding.ISO)
     override val defaultEncoding = Encoding.PETSCII
 
     companion object {

codeCore/src/prog8/code/target/Encoder.kt

@@ -10,6 +10,8 @@ import prog8.code.target.cbm.PetsciiEncoding
 
 
 object Encoder: IStringEncoding {
+    override val defaultEncoding: Encoding = Encoding.ISO
+
     override fun encodeString(str: String, encoding: Encoding): List<UByte> {
         val coded = when(encoding) {
             Encoding.PETSCII -> PetsciiEncoding.encodePetscii(str, true)

codeCore/src/prog8/code/target/PETTarget.kt

@@ -0,0 +1,19 @@
+package prog8.code.target
+
+import prog8.code.core.Encoding
+import prog8.code.core.ICompilationTarget
+import prog8.code.core.IMemSizer
+import prog8.code.core.IStringEncoding
+import prog8.code.target.cbm.CbmMemorySizer
+import prog8.code.target.pet.PETMachineDefinition
+
+
+class PETTarget: ICompilationTarget, IStringEncoding by Encoder, IMemSizer by CbmMemorySizer {
+    override val name = NAME
+    override val machine = PETMachineDefinition()
+    override val defaultEncoding = Encoding.PETSCII
+
+    companion object {
+        const val NAME = "pet32"
+    }
+}

codeCore/src/prog8/code/target/VMTarget.kt

@@ -6,7 +6,6 @@ import prog8.code.target.virtual.VirtualMachineDefinition
 class VMTarget: ICompilationTarget, IStringEncoding by Encoder, IMemSizer {
     override val name = NAME
     override val machine = VirtualMachineDefinition()
-    override val supportedEncodings = setOf(Encoding.ISO)
     override val defaultEncoding = Encoding.ISO
 
     companion object {

codeCore/src/prog8/code/target/atari/AtariMachineDefinition.kt

@@ -13,10 +13,6 @@ class AtariMachineDefinition: IMachineDefinition {
     override val FLOAT_MEM_SIZE = 6
     override val PROGRAM_LOAD_ADDRESS = 0x2000u
 
-    // the 2*128 byte evaluation stack (1 page, on which bytes, words, and even floats are stored during calculations)
-    override var ESTACK_LO = 0x1b00u     //  $1b00-$1b7f inclusive      // TODO
-    override var ESTACK_HI = 0x1b80u     //  $1b80-$1bff inclusive      // TODO
-
     override val BSSHIGHRAM_START = 0u    // TODO
     override val BSSHIGHRAM_END = 0u      // TODO
 

codeCore/src/prog8/code/target/atari/AtariZeropage.kt

@@ -48,6 +48,7 @@ class AtariZeropage(options: CompilationOptions) : Zeropage(options) {
         free.addAll(distinctFree)
 
         removeReservedFromFreePool()
+        retainAllowed()
     }
 
     override fun allocateCx16VirtualRegisters() {

codeCore/src/prog8/code/target/c128/C128MachineDefinition.kt

@@ -15,10 +15,6 @@ class C128MachineDefinition: IMachineDefinition {
     override val FLOAT_MEM_SIZE = Mflpt5.FLOAT_MEM_SIZE
     override val PROGRAM_LOAD_ADDRESS = 0x1c01u
 
-    // the 2*128 byte evaluation stack (1 page, on which bytes, words, and even floats are stored during calculations)
-    override var ESTACK_LO = 0x1b00u     //  $1b00-$1b7f inclusive
-    override var ESTACK_HI = 0x1b80u     //  $1b80-$1bff inclusive
-
     override val BSSHIGHRAM_START = 0u    // TODO
     override val BSSHIGHRAM_END = 0u      // TODO
 

codeCore/src/prog8/code/target/c128/C128Zeropage.kt

@@ -69,6 +69,7 @@ class C128Zeropage(options: CompilationOptions) : Zeropage(options) {
         free.addAll(distinctFree)
 
         removeReservedFromFreePool()
+        retainAllowed()
     }
 
     override fun allocateCx16VirtualRegisters() {

codeCore/src/prog8/code/target/c64/C64MachineDefinition.kt

@@ -16,12 +16,8 @@ class C64MachineDefinition: IMachineDefinition {
     override val FLOAT_MEM_SIZE = Mflpt5.FLOAT_MEM_SIZE
     override val PROGRAM_LOAD_ADDRESS = 0x0801u
 
-    // the 2*128 byte evaluation stack (1 page, on which bytes, words, and even floats are stored during calculations)
-    override var ESTACK_LO = 0xcf00u     //  $cf00-$cf7f inclusive
-    override var ESTACK_HI = 0xcf80u     //  $cf80-$cfff inclusive
-
     override val BSSHIGHRAM_START = 0xc000u
-    override val BSSHIGHRAM_END = ESTACK_LO
+    override val BSSHIGHRAM_END = 0xd000u
 
     override lateinit var zeropage: Zeropage
     override lateinit var golden: GoldenRam
@@ -62,7 +58,7 @@ class C64MachineDefinition: IMachineDefinition {
 
     override fun initializeMemoryAreas(compilerOptions: CompilationOptions) {
         zeropage = C64Zeropage(compilerOptions)
-        golden = GoldenRam(compilerOptions, 0xc000u until ESTACK_LO)
+        golden = GoldenRam(compilerOptions, 0xc000u until 0xd000u)
     }
 
 }

codeCore/src/prog8/code/target/c64/C64Zeropage.kt

@@ -53,11 +53,11 @@ class C64Zeropage(options: CompilationOptions) : Zeropage(options) {
                 ).map{it.toUInt()})
             }
 
-            if(options.zeropage!= ZeropageType.DONTUSE) {
+            if(options.zeropage != ZeropageType.DONTUSE) {
                 // add the free Zp addresses
                 // these are valid for the C-64 but allow BASIC to keep running fully *as long as you don't use tape I/O*
                 free.addAll(listOf(0x02, 0x03, 0x04, 0x05, 0x06, 0x0a, 0x0e,
-                        0x92, 0x96, 0x9b, 0x9c, 0x9e, 0x9f, 0xa5, 0xa6,
+                        0x92, 0x96, 0x9b, 0x9c, 0x9e, 0x9f, 0xa6,
                         0xb0, 0xb1, 0xbe, 0xbf, 0xf9).map{it.toUInt()})
             } else {
                 // don't use the zeropage at all
@@ -75,6 +75,8 @@ class C64Zeropage(options: CompilationOptions) : Zeropage(options) {
             // in these cases there is enough space on the zero page to stick the cx16 virtual registers in there as well.
             allocateCx16VirtualRegisters()
         }
+
+        retainAllowed()
     }
 
     override fun allocateCx16VirtualRegisters() {

codeCore/src/prog8/code/target/cbm/PetsciiEncoding.kt

@@ -24,7 +24,7 @@ object PetsciiEncoding {
         '\ufffe',    //       0x0A -> UNDEFINED
         '\ufffe',    //       0x0B -> UNDEFINED
         '\ufffe',    //       0x0C -> UNDEFINED
-        '\r'    ,    //       0x0D -> CARRIAGE RETURN
+        '\n'    ,    //       0x0D -> LINE FEED (RETURN)
         '\u000e',    //       0x0E -> SHIFT OUT
         '\ufffe',    //       0x0F -> UNDEFINED
         '\ufffe',    //       0x10 -> UNDEFINED
@@ -152,7 +152,7 @@ object PetsciiEncoding {
         '\uf113',    //      0x8A -> FUNCTION KEY 4 (CUS)
         '\uf115',    //      0x8B -> FUNCTION KEY 6 (CUS)
         '\uf117',    //      0x8C -> FUNCTION KEY 8 (CUS)
-        '\n'    ,    //       0x8D -> LINE FEED
+        '\r'    ,    //       0x8D -> CARRIAGE RETURN (SHIFT-RETURN)
         '\u000f',    //      0x8E -> SHIFT IN
         '\ufffe',    //       0x8F -> UNDEFINED
         '\uf105',    //       0x90 -> BLACK COLOR SWITCH (CUS)
@@ -283,7 +283,7 @@ object PetsciiEncoding {
         '\ufffe',    //       0x0A -> UNDEFINED
         '\ufffe',    //       0x0B -> UNDEFINED
         '\ufffe',    //       0x0C -> UNDEFINED
-        '\r'    ,    //       0x0D -> CARRIAGE RETURN
+        '\n'    ,    //       0x0D -> LINE FEED (RETURN)
         '\u000e',    //       0x0E -> SHIFT OUT
         '\ufffe',    //       0x0F -> UNDEFINED
         '\ufffe',    //       0x10 -> UNDEFINED
@@ -411,7 +411,7 @@ object PetsciiEncoding {
         '\uf113',    //       0x8A -> FUNCTION KEY 4 (CUS)
         '\uf115',    //       0x8B -> FUNCTION KEY 6 (CUS)
         '\uf117',    //       0x8C -> FUNCTION KEY 8 (CUS)
-        '\n'    ,    //       0x8D -> LINE FEED
+        '\r'    ,    //       0x8D -> CARRIAGE RETURN (SHIFT-RETURN)
         '\u000f',    //       0x8E -> SHIFT IN
         '\ufffe',    //       0x8F -> UNDEFINED
         '\uf105',    //       0x90 -> BLACK COLOR SWITCH (CUS)
@@ -1061,6 +1061,7 @@ object PetsciiEncoding {
             '}' -> '├'
             '|' -> '│'
             '\\' -> '╲'
+            '\r' -> '\n'        // to make \r (carriage returrn) equivalent to \n (line feed): RETURN ($0d)
             else -> chr
         }
 
@@ -1076,7 +1077,10 @@ object PetsciiEncoding {
                 }
                 else -> {
                     val case = if (lowercase) "lower" else "upper"
-                    throw CharConversionException("no ${case}Petscii character for '${chr}' (${chr.code})")
+                    if(chr.isISOControl())
+                        throw CharConversionException("no ${case}Petscii character for char #${chr.code}")
+                    else
+                        throw CharConversionException("no ${case}Petscii character for char #${chr.code} '${chr}'")
                 }
             }
         }
@@ -1119,7 +1123,10 @@ object PetsciiEncoding {
                 }
                 else -> {
                     val case = if (lowercase) "lower" else "upper"
-                    throw CharConversionException("no ${case}Screencode character for '${chr}' (${chr.code})")
+                    if(chr.isISOControl())
+                        throw CharConversionException("no ${case}Screencode character for char #${chr.code}")
+                    else
+                        throw CharConversionException("no ${case}Screencode character for char #${chr.code} '${chr}'")
                 }
             }
         }

codeCore/src/prog8/code/target/cx16/CX16MachineDefinition.kt

@@ -15,10 +15,6 @@ class CX16MachineDefinition: IMachineDefinition {
     override val FLOAT_MEM_SIZE = Mflpt5.FLOAT_MEM_SIZE
     override val PROGRAM_LOAD_ADDRESS = 0x0801u
 
-    // the 2*128 byte evaluation stack (1 page, on which bytes, words, and even floats are stored during calculations)
-    override var ESTACK_LO = 0x0700u        //  $0700-$077f inclusive
-    override var ESTACK_HI = 0x0780u        //  $0780-$07ff inclusive
-
     override val BSSHIGHRAM_START = 0xa000u     // hiram bank 1, 8Kb, assumed to be active
     override val BSSHIGHRAM_END = 0xc000u       // rom starts here.
 
@@ -64,7 +60,7 @@ class CX16MachineDefinition: IMachineDefinition {
 
     override fun initializeMemoryAreas(compilerOptions: CompilationOptions) {
         zeropage = CX16Zeropage(compilerOptions)
-        golden = GoldenRam(compilerOptions, 0x0400u until ESTACK_LO)
+        golden = GoldenRam(compilerOptions, 0x0400u until 0x0800u)
     }
 
 }

codeCore/src/prog8/code/target/cx16/CX16Zeropage.kt

@@ -40,7 +40,6 @@ class CX16Zeropage(options: CompilationOptions) : Zeropage(options) {
                 ZeropageType.DONTUSE -> {
                     free.clear() // don't use zeropage at all
                 }
-                else -> throw InternalCompilerException("for this machine target, zero page type 'floatsafe' is not available. ${options.zeropage}")
             }
 
             val distinctFree = free.distinct()
@@ -48,8 +47,8 @@ class CX16Zeropage(options: CompilationOptions) : Zeropage(options) {
             free.addAll(distinctFree)
 
             removeReservedFromFreePool()
-
             allocateCx16VirtualRegisters()
+            retainAllowed()
         }
     }
 

codeCore/src/prog8/code/target/pet/PETMachineDefinition.kt

@@ -0,0 +1,55 @@
+package prog8.code.target.pet
+
+import prog8.code.core.*
+import prog8.code.target.C64Target
+import prog8.code.target.cbm.Mflpt5
+import java.nio.file.Path
+
+
+class PETMachineDefinition: IMachineDefinition {
+
+    override val cpu = CpuType.CPU6502
+
+    override val FLOAT_MAX_POSITIVE = Mflpt5.FLOAT_MAX_POSITIVE
+    override val FLOAT_MAX_NEGATIVE = Mflpt5.FLOAT_MAX_NEGATIVE
+    override val FLOAT_MEM_SIZE = Mflpt5.FLOAT_MEM_SIZE
+    override val PROGRAM_LOAD_ADDRESS = 0x0401u
+
+    override val BSSHIGHRAM_START = 0xffffu
+    override val BSSHIGHRAM_END = 0xffffu
+
+    override lateinit var zeropage: Zeropage
+    override lateinit var golden: GoldenRam
+
+    override fun getFloatAsmBytes(num: Number) = Mflpt5.fromNumber(num).makeFloatFillAsm()
+
+    override fun importLibs(compilerOptions: CompilationOptions, compilationTargetName: String): List<String> {
+        return if (compilerOptions.launcher == CbmPrgLauncherType.BASIC || compilerOptions.output == OutputType.PRG)
+            listOf("syslib")
+        else
+            emptyList()
+    }
+
+    override fun launchEmulator(selectedEmulator: Int, programNameWithPath: Path) {
+        if(selectedEmulator!=1) {
+            System.err.println("The pet target only supports the main emulator (Vice).")
+            return
+        }
+
+        println("\nStarting PET emulator...")
+        val viceMonlist = C64Target.viceMonListName(programNameWithPath.toString())
+        val cmdline = listOf("xpet", "-model", "4032", "-ramsize", "32", "-videosize", "40", "-silent", "-moncommands", viceMonlist,
+                "-autostartprgmode", "1", "-autostart-warp", "-autostart", "${programNameWithPath}.prg")
+        val processb = ProcessBuilder(cmdline).inheritIO()
+        val process=processb.start()
+        process.waitFor()
+    }
+
+    override fun isIOAddress(address: UInt): Boolean = address in 0xe800u..0xe8ffu
+
+    override fun initializeMemoryAreas(compilerOptions: CompilationOptions) {
+        zeropage = PETZeropage(compilerOptions)
+        // there's no golden ram.
+    }
+
+}

codeCore/src/prog8/code/target/pet/PETZeropage.kt

@@ -0,0 +1,59 @@
+package prog8.code.target.pet
+
+import prog8.code.core.CompilationOptions
+import prog8.code.core.InternalCompilerException
+import prog8.code.core.Zeropage
+import prog8.code.core.ZeropageType
+
+
+// reference: http://www.zimmers.net/cbmpics/cbm/PETx/petmem.txt
+
+class PETZeropage(options: CompilationOptions) : Zeropage(options) {
+
+    override val SCRATCH_B1 = 0xb3u      // temp storage for a single byte
+    override val SCRATCH_REG = 0xb4u     // temp storage for a register, must be B1+1
+    override val SCRATCH_W1 = 0xb6u      // temp storage 1 for a word
+    override val SCRATCH_W2 = 0xb8u      // temp storage 2 for a word
+
+    init {
+        if (options.floats) {
+            throw InternalCompilerException("PET target doesn't yet support floating point routines")
+        }
+
+        if (options.floats && options.zeropage !in arrayOf(
+                ZeropageType.FLOATSAFE,
+                ZeropageType.BASICSAFE,
+                ZeropageType.DONTUSE
+            ))
+            throw InternalCompilerException("when floats are enabled, zero page type should be 'floatsafe' or 'basicsafe' or 'dontuse'")
+
+        when (options.zeropage) {
+            ZeropageType.FULL -> {
+                free.addAll(0x00u..0xffu)
+                free.removeAll(listOf(0x8du, 0x8eu, 0x8fu, 0x97u, 0x98u, 0x99u, 0x9au, 0x9bu, 0x9eu, 0xa7u, 0xa8u, 0xa9u, 0xaau))        // these are updated/used by IRQ
+            }
+            ZeropageType.KERNALSAFE -> {
+                free.addAll(0x00u..0xffu)
+                free.removeAll(listOf(0x8du, 0x8eu, 0x8fu, 0x97u, 0x98u, 0x99u, 0x9au, 0x9bu, 0x9eu, 0xa7u, 0xa8u, 0xa9u, 0xaau))        // these are updated/used by IRQ
+            }
+            ZeropageType.FLOATSAFE,
+            ZeropageType.BASICSAFE -> {
+                free.addAll(0xb3u..0xbau)       // TODO more?
+            }
+            ZeropageType.DONTUSE -> {
+                free.clear()  // don't use zeropage at all
+            }
+        }
+
+        val distinctFree = free.distinct()
+        free.clear()
+        free.addAll(distinctFree)
+
+        removeReservedFromFreePool()
+        retainAllowed()
+    }
+
+    override fun allocateCx16VirtualRegisters() {
+        TODO("Not known if PET can put the virtual regs in ZP")
+    }
+}

codeCore/src/prog8/code/target/virtual/VirtualMachineDefinition.kt

@@ -12,11 +12,9 @@ class VirtualMachineDefinition: IMachineDefinition {
 
     override val FLOAT_MAX_POSITIVE = Float.MAX_VALUE.toDouble()
     override val FLOAT_MAX_NEGATIVE = -Float.MAX_VALUE.toDouble()
-    override val FLOAT_MEM_SIZE = 4             // 32-bits floating point
+    override val FLOAT_MEM_SIZE = 8             // 64-bits double
     override val PROGRAM_LOAD_ADDRESS = 0u      // not actually used
 
-    override var ESTACK_LO = 0u                 // not actually used
-    override var ESTACK_HI = 0u                 // not actually used
     override val BSSHIGHRAM_START = 0u          // not actually used
     override val BSSHIGHRAM_END = 0u            // not actually used
     override lateinit var zeropage: Zeropage    // not actually used
@@ -24,8 +22,8 @@ class VirtualMachineDefinition: IMachineDefinition {
 
     override fun getFloatAsmBytes(num: Number): String {
         // little endian binary representation
-        val bits = num.toFloat().toBits().toUInt()
-        val hexStr = bits.toString(16).padStart(8, '0')
+        val bits = num.toDouble().toBits().toULong()
+        val hexStr = bits.toString(16).padStart(16, '0')
         val parts = hexStr.chunked(2).map { "\$" + it }
         return parts.joinToString(", ")
     }

codeGenCpu6502/build.gradle

@@ -30,16 +30,16 @@ dependencies {
     // implementation "org.jetbrains.kotlin:kotlin-reflect"
     implementation "com.michael-bull.kotlin-result:kotlin-result-jvm:1.1.18"
 
-    testImplementation 'io.kotest:kotest-runner-junit5-jvm:5.6.2'
+    testImplementation 'io.kotest:kotest-runner-junit5-jvm:5.8.0'
 }
 
 sourceSets {
     main {
         java {
-            srcDirs = ["${project.projectDir}/src"]
+            srcDir "${project.projectDir}/src"
         }
         resources {
-            srcDirs = ["${project.projectDir}/res"]
+            srcDir "${project.projectDir}/res"
         }
     }
     test {

codeGenCpu6502/src/prog8/codegen/cpu6502/AsmGen.kt

@@ -172,8 +172,6 @@ private fun PtFunctionCall.prefix(parent: PtNode): PtFunctionCall {
     call.children.addAll(children)
     call.children.forEach { it.parent = call }
     call.parent = parent
-    if(name.endsWith("concat_string"))
-        println("CONCAT ${this.position}")
     return call
 }
 
@@ -203,12 +201,12 @@ class AsmGen6502Internal (
     private val allocator = VariableAllocator(symbolTable, options, errors)
     private val assemblyLines = mutableListOf<String>()
     private val breakpointLabels = mutableListOf<String>()
-    private val forloopsAsmGen = ForLoopsAsmGen(program, this, zeropage)
+    private val forloopsAsmGen = ForLoopsAsmGen(this, zeropage)
     private val postincrdecrAsmGen = PostIncrDecrAsmGen(program, this)
     private val functioncallAsmGen = FunctionCallAsmGen(program, this)
     private val programGen = ProgramAndVarsGen(program, options, errors, symbolTable, functioncallAsmGen, this, allocator, zeropage)
-    private val assignmentAsmGen = AssignmentAsmGen(program, symbolTable, this, allocator)
-    private val expressionsAsmGen = ExpressionsAsmGen(program, this, allocator)
+    private val anyExprGen = AnyExprAsmGen(this)
+    private val assignmentAsmGen = AssignmentAsmGen(program, this, anyExprGen, allocator)
     private val builtinFunctionsAsmGen = BuiltinFunctionsAsmGen(program, this, assignmentAsmGen)
 
     fun compileToAssembly(): IAssemblyProgram? {
@@ -240,8 +238,19 @@ class AsmGen6502Internal (
 
     internal fun isTargetCpu(cpu: CpuType) = options.compTarget.machine.cpu == cpu
 
+    private var lastSourceLineNumber: Int = -1
+
     internal fun outputSourceLine(node: PtNode) {
-        out(" ;\tsrc line: ${node.position.file}:${node.position.line}")
+        if(!options.includeSourcelines || node.position===Position.DUMMY || node.position.line==lastSourceLineNumber)
+            return
+
+        lastSourceLineNumber = node.position.line
+        val srcComment = "\t; source: ${node.position.file}:${node.position.line}"
+        val line = SourceLineCache.retrieveLine(node.position)
+        if(line==null)
+            out(srcComment, false)
+        else
+            out("$srcComment   $line", false)
     }
 
     internal fun out(str: String, splitlines: Boolean = true) {
@@ -394,32 +403,6 @@ class AsmGen6502Internal (
         return name2.replace("prog8_lib.P8ZP_SCRATCH_", "P8ZP_SCRATCH_")    // take care of the 'hooks' to the temp vars -> reference zp symbols directly
     }
 
-    internal fun saveRegisterLocal(register: CpuRegister, scope: IPtSubroutine) {
-        if (isTargetCpu(CpuType.CPU65c02)) {
-            // just use the cpu's stack for all registers, shorter code
-            when (register) {
-                CpuRegister.A -> out("  pha")
-                CpuRegister.X -> out("  phx")
-                CpuRegister.Y -> out("  phy")
-            }
-        } else {
-            when (register) {
-                CpuRegister.A -> {
-                    // just use the stack, only for A
-                    out("  pha")
-                }
-                CpuRegister.X -> {
-                    out("  stx  prog8_regsaveX")
-                    subroutineExtra(scope).usedRegsaveX = true
-                }
-                CpuRegister.Y -> {
-                    out("  sty  prog8_regsaveY")
-                    subroutineExtra(scope).usedRegsaveY = true
-                }
-            }
-        }
-    }
-
     internal fun saveRegisterStack(register: CpuRegister, keepA: Boolean) {
         when (register) {
             CpuRegister.A -> out("  pha")
@@ -444,24 +427,6 @@ class AsmGen6502Internal (
         }
     }
 
-    internal fun restoreRegisterLocal(register: CpuRegister) {
-        if (isTargetCpu(CpuType.CPU65c02)) {
-            when (register) {
-                // this just used the stack, for all registers. Shorter code.
-                CpuRegister.A -> out("  pla")
-                CpuRegister.X -> out("  plx")
-                CpuRegister.Y -> out("  ply")
-            }
-
-        } else {
-            when (register) {
-                CpuRegister.A -> out("  pla")   // this just used the stack but only for A
-                CpuRegister.X -> out("  ldx  prog8_regsaveX")
-                CpuRegister.Y -> out("  ldy  prog8_regsaveY")
-            }
-        }
-    }
-
     internal fun restoreRegisterStack(register: CpuRegister, keepA: Boolean) {
         when (register) {
             CpuRegister.A -> {
@@ -538,24 +503,18 @@ class AsmGen6502Internal (
             return
         }
 
-        val indexVar = expr.index as? PtIdentifier
-            ?: throw AssemblyError("array indexer should have been replaced with a temp var @ ${expr.index.position}")
-
-        val indexName = asmVariableName(indexVar)
-
         if(expr.splitWords) {
-            when (register) {
-                CpuRegister.A -> out("  lda  $indexName")
-                CpuRegister.X -> out("  ldx  $indexName")
-                CpuRegister.Y -> out("  ldy  $indexName")
-            }
+            assignExpressionToRegister(expr.index, RegisterOrPair.fromCpuRegister(register), false)
             return
         }
 
         when (elementDt) {
-            in ByteDatatypes -> out("  ld$reg  $indexName")
+            in ByteDatatypes -> {
+                assignExpressionToRegister(expr.index, RegisterOrPair.fromCpuRegister(register), false)
+            }
             in WordDatatypes -> {
-                out("  lda  $indexName |  asl  a")
+                assignExpressionToRegister(expr.index, RegisterOrPair.A, false)
+                out("  asl  a")
                 when (register) {
                     CpuRegister.A -> {}
                     CpuRegister.X -> out(" tax")
@@ -564,12 +523,13 @@ class AsmGen6502Internal (
             }
             DataType.FLOAT -> {
                 require(options.compTarget.memorySize(DataType.FLOAT) == 5) {"invalid float size ${expr.position}"}
+                assignExpressionToRegister(expr.index, RegisterOrPair.A, false)
                 out("""
-                    lda  $indexName
+                    sta  P8ZP_SCRATCH_REG
                     asl  a
                     asl  a
                     clc
-                    adc  $indexName"""
+                    adc  P8ZP_SCRATCH_REG"""
                 )
                 when (register) {
                     CpuRegister.A -> {}
@@ -581,22 +541,12 @@ class AsmGen6502Internal (
         }
     }
 
-    @Deprecated("avoid calling this as it generates slow evalstack based code")
-    internal fun translateExpression(expression: PtExpression) =
-            expressionsAsmGen.translateExpression(expression)
-
-    internal fun translateBuiltinFunctionCallExpression(bfc: PtBuiltinFunctionCall, resultToStack: Boolean, resultRegister: RegisterOrPair?): DataType? =
-            builtinFunctionsAsmGen.translateFunctioncallExpression(bfc, resultToStack, resultRegister)
+    internal fun translateBuiltinFunctionCallExpression(bfc: PtBuiltinFunctionCall, resultRegister: RegisterOrPair?): DataType? =
+            builtinFunctionsAsmGen.translateFunctioncallExpression(bfc, resultRegister)
 
     internal fun translateFunctionCall(functionCallExpr: PtFunctionCall) =
             functioncallAsmGen.translateFunctionCall(functionCallExpr)
 
-    internal fun saveXbeforeCall(functionCall: PtFunctionCall)  =
-            functioncallAsmGen.saveXbeforeCall(functionCall)
-
-    internal fun restoreXafterCall(functionCall: PtFunctionCall) =
-            functioncallAsmGen.restoreXafterCall(functionCall)
-
     internal fun translateNormalAssignment(assign: AsmAssignment, scope: IPtSubroutine?) =
             assignmentAsmGen.translateNormalAssignment(assign, scope)
 
@@ -613,7 +563,7 @@ class AsmGen6502Internal (
         when(reg) {
             RegisterOrPair.A,
             RegisterOrPair.X,
-            RegisterOrPair.Y -> assignmentAsmGen.assignRegisterByte(target, reg.asCpuRegister(), target.datatype in SignedDatatypes)
+            RegisterOrPair.Y -> assignmentAsmGen.assignRegisterByte(target, reg.asCpuRegister(), target.datatype in SignedDatatypes, true)
             RegisterOrPair.AX,
             RegisterOrPair.AY,
             RegisterOrPair.XY,
@@ -625,9 +575,36 @@ class AsmGen6502Internal (
     }
 
     internal fun assignExpressionTo(value: PtExpression, target: AsmAssignTarget) {
-        // don't use translateExpression() to avoid evalstack
         when (target.datatype) {
             in ByteDatatypes -> {
+                if (value.asConstInteger()==0) {
+                    when(target.kind) {
+                        TargetStorageKind.VARIABLE -> {
+                            if (isTargetCpu(CpuType.CPU6502))
+                                out("lda  #0 |  sta  ${target.asmVarname}")
+                            else
+                                out("stz  ${target.asmVarname}")
+                        }
+                        TargetStorageKind.MEMORY -> {
+                            val address = target.memory!!.address.asConstInteger()
+                            if(address!=null) {
+                                if (isTargetCpu(CpuType.CPU6502))
+                                    out("lda  #0 |  sta  ${address.toHex()}")
+                                else
+                                    out("  stz  ${address.toHex()}")
+                                return
+                            }
+                        }
+                        TargetStorageKind.REGISTER -> {
+                            val zero = PtNumber(DataType.UBYTE, 0.0, value.position)
+                            zero.parent = value
+                            assignExpressionToRegister(zero, target.register!!, false)
+                            return
+                        }
+                        else -> { }
+                    }
+                }
+
                 assignExpressionToRegister(value, RegisterOrPair.A)
                 assignRegister(RegisterOrPair.A, target)
             }
@@ -907,7 +884,7 @@ $repeatLabel""")
             DataType.UBYTE, DataType.UWORD -> {
                 val result = zeropage.allocate(counterVar, dt, null, stmt.position, errors)
                 result.fold(
-                    success = { (address, _) -> asmInfo.extraVars.add(Triple(dt, counterVar, address)) },
+                    success = { (address, _, _) -> asmInfo.extraVars.add(Triple(dt, counterVar, address)) },
                     failure = { asmInfo.extraVars.add(Triple(dt, counterVar, null)) }  // allocate normally
                 )
                 return counterVar
@@ -1047,7 +1024,10 @@ $repeatLabel""")
     }
 
     private fun translate(asm: PtInlineAssembly) {
-        assemblyLines.add(asm.assembly.trimEnd().trimStart('\r', '\n'))
+        if(asm.isIR)
+            throw AssemblyError("%asm containing IR code cannot be translated to 6502 assembly")
+        else
+            assemblyLines.add(asm.assembly.trimEnd().trimStart('\r', '\n'))
     }
 
     private fun translate(incbin: PtIncludeBinary) {
@@ -1069,6 +1049,15 @@ $repeatLabel""")
         val label = "_prog8_breakpoint_${breakpointLabels.size+1}"
         breakpointLabels.add(label)
         out(label)
+        if(options.breakpointCpuInstruction) {
+            val instruction =
+                when(options.compTarget.machine.cpu) {
+                    CpuType.CPU6502 -> "brk"
+                    CpuType.CPU65c02 -> "stp"
+                    else -> throw AssemblyError("invalid cpu type")
+                }
+            out("  $instruction")
+        }
     }
 
     internal fun signExtendAYlsb(valueDt: DataType) {
@@ -1086,20 +1075,6 @@ $repeatLabel""")
         }
     }
 
-    internal fun signExtendStackLsb(valueDt: DataType) {
-        // sign extend signed byte on stack to signed word on stack
-        when(valueDt) {
-            DataType.UBYTE -> {
-                if(isTargetCpu(CpuType.CPU65c02))
-                    out("  stz  P8ESTACK_HI+1,x")
-                else
-                    out("  lda  #0 |  sta  P8ESTACK_HI+1,x")
-            }
-            DataType.BYTE -> out("  jsr  prog8_lib.sign_extend_stack_byte")
-            else -> throw AssemblyError("need byte type")
-        }
-    }
-
     internal fun signExtendVariableLsb(asmvar: String, valueDt: DataType) {
         // sign extend signed byte in a var to a full word in that variable
         when(valueDt) {
@@ -1728,7 +1703,7 @@ $repeatLabel""")
                 }
                 else if (left is PtMemoryByte) {
                     return if(rightConstVal.number.toInt()!=0) {
-                        translateDirectMemReadExpressionToRegAorStack(left, false)
+                        translateDirectMemReadExpressionToRegA(left)
                         code("#${rightConstVal.number.toInt()}")
                     }
                     else
@@ -1875,7 +1850,7 @@ $repeatLabel""")
                         out("  beq $jumpIfFalseLabel")
                 }
                 else if (left is PtMemoryByte) {
-                    translateDirectMemReadExpressionToRegAorStack(left, false)
+                    translateDirectMemReadExpressionToRegA(left)
                     return if(rightConstVal.number.toInt()!=0)
                         code("#${rightConstVal.number.toInt()}")
                     else
@@ -2036,7 +2011,7 @@ $repeatLabel""")
                         out("  bne  $jumpIfFalseLabel")
                 }
                 else if (left is PtMemoryByte) {
-                    translateDirectMemReadExpressionToRegAorStack(left, false)
+                    translateDirectMemReadExpressionToRegA(left)
                     return if(rightConstVal.number.toInt()!=0)
                         code("#${rightConstVal.number.toInt()}")
                     else
@@ -2200,7 +2175,7 @@ $repeatLabel""")
                 }
                 else if (left is PtMemoryByte) {
                     if(rightConstVal.number.toInt()!=0) {
-                        translateDirectMemReadExpressionToRegAorStack(left, false)
+                        translateDirectMemReadExpressionToRegA(left)
                         code("#${rightConstVal.number.toInt()}")
                     }
                     return
@@ -2363,7 +2338,7 @@ $repeatLabel""")
                         out("  bne  $jumpIfFalseLabel")
                 }
                 else if (left is PtMemoryByte) {
-                    translateDirectMemReadExpressionToRegAorStack(left, false)
+                    translateDirectMemReadExpressionToRegA(left)
                     return if(rightConstVal.number.toInt()!=0)
                         code("#${rightConstVal.number.toInt()}")
                     else
@@ -2409,7 +2384,7 @@ $repeatLabel""")
                         out("  beq  $jumpIfFalseLabel")
                 }
                 else if (left is PtMemoryByte) {
-                    translateDirectMemReadExpressionToRegAorStack(left, false)
+                    translateDirectMemReadExpressionToRegA(left)
                     return if(rightConstVal.number.toInt()!=0)
                         code("#${rightConstVal.number.toInt()}")
                     else
@@ -2474,8 +2449,7 @@ $repeatLabel""")
                     cmp  #<$number
                     bne  $jumpIfFalseLabel
                     cpy  #>$number
-                    bne  $jumpIfFalseLabel
-                    """)
+                    bne  $jumpIfFalseLabel""")
             }
             is PtIdentifier -> {
                 assignExpressionToRegister(left, RegisterOrPair.AY)
@@ -2483,18 +2457,21 @@ $repeatLabel""")
                     cmp  ${asmVariableName(right)}
                     bne  $jumpIfFalseLabel
                     cpy  ${asmVariableName(right)}+1
-                    bne  $jumpIfFalseLabel
-                    """)
+                    bne  $jumpIfFalseLabel""")
             }
             is PtAddressOf -> {
                 assignExpressionToRegister(left, RegisterOrPair.AY)
                 val name = asmSymbolName(right.identifier)
-                out("""
-                    cmp  #<$name
-                    bne  $jumpIfFalseLabel
-                    cpy  #>$name
-                    bne  $jumpIfFalseLabel
-                    """)
+                if(right.isFromArrayElement) {
+                    TODO("address-of array element $name at ${right.position}")
+                    // assignmentAsmGen.assignAddressOf(target, name, right.arrayIndexExpr)
+                } else {
+                    out("""
+                        cmp  #<$name
+                        bne  $jumpIfFalseLabel
+                        cpy  #>$name
+                        bne  $jumpIfFalseLabel""")
+                }
             }
             else -> {
                 if(left.isSimple()) {
@@ -2575,12 +2552,16 @@ $repeatLabel""")
             is PtAddressOf -> {
                 assignExpressionToRegister(left, RegisterOrPair.AY)
                 val name = asmSymbolName(right.identifier)
-                out("""
-                    cmp  #<$name
-                    bne  +
-                    cpy  #>$name
-                    beq  $jumpIfFalseLabel
-+""")
+                if(right.isFromArrayElement) {
+                    TODO("address-of array element $name at ${right.position}")
+                } else {
+                    out("""
+                        cmp  #<$name
+                        bne  +
+                        cpy  #>$name
+                        beq  $jumpIfFalseLabel
+    +""")
+                }
             }
             else -> {
                 if(left.isSimple()) {
@@ -2865,22 +2846,14 @@ $repeatLabel""")
 +""")
     }
 
-    internal fun translateDirectMemReadExpressionToRegAorStack(expr: PtMemoryByte, pushResultOnEstack: Boolean) {
+    internal fun translateDirectMemReadExpressionToRegA(expr: PtMemoryByte) {
 
         fun assignViaExprEval() {
             assignExpressionToVariable(expr.address, "P8ZP_SCRATCH_W2", DataType.UWORD)
             if (isTargetCpu(CpuType.CPU65c02)) {
-                if (pushResultOnEstack) {
-                    out("  lda  (P8ZP_SCRATCH_W2) |  dex |  sta  P8ESTACK_LO+1,x")
-                } else {
-                    out("  lda  (P8ZP_SCRATCH_W2)")
-                }
+                out("  lda  (P8ZP_SCRATCH_W2)")
             } else {
-                if (pushResultOnEstack) {
-                    out("  ldy  #0 |  lda  (P8ZP_SCRATCH_W2),y |  dex |  sta  P8ESTACK_LO+1,x")
-                } else {
-                    out("  ldy  #0 |  lda  (P8ZP_SCRATCH_W2),y")
-                }
+                out("  ldy  #0 |  lda  (P8ZP_SCRATCH_W2),y")
             }
         }
 
@@ -2888,21 +2861,14 @@ $repeatLabel""")
             is PtNumber -> {
                 val address = (expr.address as PtNumber).number.toInt()
                 out("  lda  ${address.toHex()}")
-                if(pushResultOnEstack)
-                    out("  sta  P8ESTACK_LO,x |  dex")
             }
             is PtIdentifier -> {
                 // the identifier is a pointer variable, so read the value from the address in it
                 loadByteFromPointerIntoA(expr.address as PtIdentifier)
-                if(pushResultOnEstack)
-                    out("  sta  P8ESTACK_LO,x |  dex")
             }
             is PtBinaryExpression -> {
                 val addrExpr = expr.address as PtBinaryExpression
-                if(tryOptimizedPointerAccessWithA(addrExpr, addrExpr.operator, false)) {
-                    if(pushResultOnEstack)
-                        out("  sta  P8ESTACK_LO,x |  dex")
-                } else {
+                if(!tryOptimizedPointerAccessWithA(addrExpr, addrExpr.operator, false)) {
                     assignViaExprEval()
                 }
             }
@@ -2921,8 +2887,12 @@ $repeatLabel""")
             is PtAddressOf -> {
                 assignExpressionToRegister(right, RegisterOrPair.AY)
                 val name = asmSymbolName(left.identifier)
-                code("#>$name", "#<$name")
-                return true
+                if(left.isFromArrayElement) {
+                    TODO("address-of array element $name at ${left.position}")
+                } else {
+                    code("#>$name", "#<$name")
+                    return true
+                }
             }
             is PtIdentifier -> {
                 assignExpressionToRegister(right, RegisterOrPair.AY)
@@ -2970,8 +2940,12 @@ $repeatLabel""")
             is PtAddressOf -> {
                 assignExpressionToRegister(left, RegisterOrPair.AY)
                 val name = asmSymbolName(right.identifier)
-                code("#>$name", "#<$name")
-                return true
+                if(right.isFromArrayElement) {
+                    TODO("address-of array element $name at ${right.position}")
+                } else {
+                    code("#>$name", "#<$name")
+                    return true
+                }
             }
             is PtIdentifier -> {
                 assignExpressionToRegister(left, RegisterOrPair.AY)
@@ -3098,6 +3072,18 @@ $repeatLabel""")
         }
     }
 
+    internal fun pushFAC1() {
+        out("  jsr  floats.pushFAC1")
+    }
+
+    internal fun popFAC1() {
+        out("  clc |  jsr  floats.popFAC")
+    }
+
+    internal fun popFAC2() {
+        out("  sec |  jsr  floats.popFAC")
+    }
+
     internal fun needAsaveForExpr(arg: PtExpression): Boolean =
         arg !is PtNumber && arg !is PtIdentifier && (arg !is PtMemoryByte || !arg.isSimple())
 
@@ -3121,6 +3107,17 @@ $repeatLabel""")
         return "prog8_label_asm_${generatedLabelSequenceNumber}_$postfix"
     }
 
+    fun assignConstFloatToPointerAY(number: PtNumber) {
+        val floatConst = allocator.getFloatAsmConst(number.number)
+        out("""
+            pha
+            lda  #<$floatConst
+            sta  P8ZP_SCRATCH_W1
+            lda  #>$floatConst
+            sta  P8ZP_SCRATCH_W1+1
+            pla
+            jsr  floats.copy_float""")
+    }
 }
 
 /**
@@ -3130,9 +3127,6 @@ $repeatLabel""")
  * it's more consistent to only define these attributes on a Subroutine node.
  */
 internal class SubroutineExtraAsmInfo {
-    var usedRegsaveA = false
-    var usedRegsaveX = false
-    var usedRegsaveY = false
     var usedFloatEvalResultVar1 = false
     var usedFloatEvalResultVar2 = false
 

codeGenCpu6502/src/prog8/codegen/cpu6502/AsmOptimizer.kt

@@ -15,21 +15,7 @@ internal fun optimizeAssembly(lines: MutableList<String>, machine: IMachineDefin
 
     var linesByFour = getLinesBy(lines, 4)
 
-    var mods = optimizeUselessStackByteWrites(linesByFour)
-    if(mods.isNotEmpty()) {
-        apply(mods, lines)
-        linesByFour = getLinesBy(lines, 4)
-        numberOfOptimizations++
-    }
-
-    mods = optimizeIncDec(linesByFour)
-    if(mods.isNotEmpty()) {
-        apply(mods, lines)
-        linesByFour = getLinesBy(lines, 4)
-        numberOfOptimizations++
-    }
-
-    mods = optimizeCmpSequence(linesByFour)
+    var mods = optimizeIncDec(linesByFour)
     if(mods.isNotEmpty()) {
         apply(mods, lines)
         linesByFour = getLinesBy(lines, 4)
@@ -57,6 +43,13 @@ internal fun optimizeAssembly(lines: MutableList<String>, machine: IMachineDefin
         numberOfOptimizations++
     }
 
+    mods = optimizeUnneededTempvarInAdd(linesByFour)
+    if(mods.isNotEmpty()) {
+        apply(mods, lines)
+        linesByFour = getLinesBy(lines, 4)
+        numberOfOptimizations++
+    }
+
     var linesByFourteen = getLinesBy(lines, 14)
     mods = optimizeSameAssignments(linesByFourteen, machine, symbolTable)
     if(mods.isNotEmpty()) {
@@ -97,44 +90,6 @@ 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> {
-    // when statement (on bytes) generates a sequence of:
-    //	 lda  $ce01,x
-    //	 cmp  #$20
-    //	 beq  check_prog8_s72choice_32
-    //	 lda  $ce01,x
-    //	 cmp  #$21
-    //	 beq  check_prog8_s73choice_33
-    // the repeated lda can be removed
-    val mods = mutableListOf<Modification>()
-    for(lines in linesByFour) {
-        if(lines[0].value.trim()=="lda  P8ESTACK_LO+1,x" &&
-                lines[1].value.trim().startsWith("cmp ") &&
-                lines[2].value.trim().startsWith("beq ") &&
-                lines[3].value.trim()=="lda  P8ESTACK_LO+1,x") {
-            mods.add(Modification(lines[3].index, true, null)) // remove the second lda
-        }
-    }
-    return mods
-}
-
-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 mods = mutableListOf<Modification>()
-    for(lines in linesByFour) {
-        if(lines[0].value.trim()=="sta  P8ESTACK_LO,x" &&
-                lines[1].value.trim()=="dex" &&
-                lines[2].value.trim()=="inx" &&
-                lines[3].value.trim()=="lda  P8ESTACK_LO,x") {
-            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 mods
-}
-
 private fun optimizeSameAssignments(
     linesByFourteen: List<List<IndexedValue<String>>>,
     machine: IMachineDefinition,
@@ -560,4 +515,27 @@ private fun optimizeUselessPushPopStack(linesByFour: List<List<IndexedValue<Stri
         optimize('y', lines)
     }
     return mods
-}
+}
+
+private fun optimizeUnneededTempvarInAdd(linesByFour: List<List<IndexedValue<String>>>): List<Modification> {
+    // sequence:  sta  P8ZP_SCRATCH_XX  / lda  something / clc / adc  P8ZP_SCRATCH_XX
+    // this can be performed without the scratch variable:  clc  /  adc  something
+    val mods = mutableListOf<Modification>()
+
+    for(lines in linesByFour) {
+        val first = lines[0].value.trimStart()
+        val second = lines[1].value.trimStart()
+        val third = lines[2].value.trimStart()
+        val fourth = lines[3].value.trimStart()
+        if(first.startsWith("sta  P8ZP_SCRATCH_") && second.startsWith("lda") && third.startsWith("clc") && fourth.startsWith("adc  P8ZP_SCRATCH_") ) {
+            if(fourth.substring(4)==first.substring(4)) {
+                mods.add(Modification(lines[0].index, false, "    clc"))
+                mods.add(Modification(lines[1].index, false, "    adc  ${second.substring(3).trimStart()}"))
+                mods.add(Modification(lines[2].index, true, null))
+                mods.add(Modification(lines[3].index, true, null))
+            }
+        }
+    }
+
+    return mods
+}

codeGenCpu6502/src/prog8/codegen/cpu6502/AsmsubHelpers.kt

@@ -1,9 +1,8 @@
 package prog8.codegen.cpu6502
 
-import prog8.code.ast.*
+import prog8.code.ast.PtAsmSub
 import prog8.code.core.Cx16VirtualRegisters
 import prog8.code.core.RegisterOrPair
-import prog8.code.core.RegisterOrStatusflag
 
 
 fun asmsub6502ArgsEvalOrder(sub: PtAsmSub): List<Int> {
@@ -11,50 +10,19 @@ fun asmsub6502ArgsEvalOrder(sub: PtAsmSub): List<Int> {
     // order is:
     //  1) cx16 virtual word registers,
     //  2) paired CPU registers,
-    //  3) single CPU registers (X last), except A,
+    //  3) single CPU registers (order Y,X,A),
     //  4) CPU Carry status flag
-    //  5) the A register itself last   (so everything before it can use the accumulator without having to save its value)
     val args = sub.parameters.withIndex()
     val (cx16regs, args2) = args.partition { it.value.first.registerOrPair in Cx16VirtualRegisters }
     val pairedRegisters = arrayOf(RegisterOrPair.AX, RegisterOrPair.AY, RegisterOrPair.XY)
     val (pairedRegs , args3) = args2.partition { it.value.first.registerOrPair in pairedRegisters }
-    val (regsWithoutA, args4) = args3.partition { it.value.first.registerOrPair != RegisterOrPair.A }
-    val (regA, rest) = args4.partition { it.value.first.registerOrPair != null }
+    val (singleRegs, rest) = args3.partition { it.value.first.registerOrPair != null }
 
     cx16regs.forEach { order += it.index }
     pairedRegs.forEach { order += it.index }
-    regsWithoutA.forEach {
-        if(it.value.first.registerOrPair != RegisterOrPair.X)
-            order += it.index
-    }
-    regsWithoutA.firstOrNull { it.value.first.registerOrPair==RegisterOrPair.X } ?.let { order += it.index}
+    singleRegs.sortedBy { it.value.first.registerOrPair!!.asCpuRegister() }.asReversed().forEach { order += it.index }
+    require(rest.all { it.value.first.registerOrPair==null && it.value.first.statusflag!=null})
     rest.forEach { order += it.index }
-    regA.forEach { order += it.index }
     require(order.size==sub.parameters.size)
     return order
 }
-
-fun asmsub6502ArgsHaveRegisterClobberRisk(
-    args: List<PtExpression>,
-    params: List<Pair<RegisterOrStatusflag, PtSubroutineParameter>>
-): Boolean {
-    fun isClobberRisk(expr: PtExpression): Boolean {
-        when (expr) {
-            is PtArrayIndexer -> {
-                return params.any {
-                    it.first.registerOrPair in listOf(RegisterOrPair.Y, RegisterOrPair.AY, RegisterOrPair.XY)
-                }
-            }
-            is PtBuiltinFunctionCall -> {
-                if (expr.name == "lsb" || expr.name == "msb")
-                    return isClobberRisk(expr.args[0])
-                if (expr.name == "mkword")
-                    return isClobberRisk(expr.args[0]) && isClobberRisk(expr.args[1])
-                return !expr.isSimple()
-            }
-            else -> return !expr.isSimple()
-        }
-    }
-
-    return args.size>1 && args.any { isClobberRisk(it) }
-}

codeGenCpu6502/src/prog8/codegen/cpu6502/AssemblyProgram.kt

@@ -1,14 +1,8 @@
 package prog8.codegen.cpu6502
 
-import com.github.michaelbull.result.Ok
-import com.github.michaelbull.result.Result
-import com.github.michaelbull.result.mapError
 import prog8.code.core.*
 import prog8.code.target.C64Target
-import java.io.File
 import java.nio.file.Path
-import kotlin.io.path.Path
-import kotlin.io.path.isRegularFile
 
 
 internal class AssemblyProgram(
@@ -28,15 +22,20 @@ internal class AssemblyProgram(
         val assemblerCommand: List<String>
 
         when (compTarget.name) {
-            in setOf("c64", "c128", "cx16") -> {
+            in setOf("c64", "c128", "cx16", "pet32") -> {
                 // CBM machines .prg generation.
 
                 // add "-Wlong-branch"  to see warnings about conversion of branch instructions to jumps (default = do this silently)
                 val command = mutableListOf("64tass", "--ascii", "--case-sensitive", "--long-branch",
-                    "-Wall", "-Wno-strict-bool", "-Wno-shadow", // "-Werror",
+                    "-Wall", // "-Wno-strict-bool", "-Werror",
                     "--dump-labels", "--vice-labels", "--labels=$viceMonListFile", "--no-monitor"
                 )
 
+                if(options.warnSymbolShadowing)
+                    command.add("-Wshadow")
+                else
+                    command.add("-Wno-shadow")
+
                 if(options.asmQuiet)
                     command.add("--quiet")
 
@@ -65,10 +64,15 @@ internal class AssemblyProgram(
 
                 // TODO are these options okay for atari?
                 val command = mutableListOf("64tass", "--ascii", "--case-sensitive", "--long-branch",
-                    "-Wall", "-Wno-strict-bool", "-Wno-shadow", // "-Werror",
+                    "-Wall", // "-Werror", "-Wno-strict-bool"
                     "--no-monitor"
                 )
 
+                if(options.warnSymbolShadowing)
+                    command.add("-Wshadow")
+                else
+                    command.add("-Wno-shadow")
+
                 if(options.asmQuiet)
                     command.add("--quiet")
 
@@ -130,18 +134,3 @@ internal class AssemblyProgram(
         viceMonListFile.toFile().appendText(breakpoints.joinToString("\n") + "\n")
     }
 }
-
-
-internal fun loadAsmIncludeFile(filename: String, source: SourceCode): Result<String, NoSuchFileException> {
-    return if (filename.startsWith(SourceCode.libraryFilePrefix)) {
-        return com.github.michaelbull.result.runCatching {
-            SourceCode.Resource("/prog8lib/${filename.substring(SourceCode.libraryFilePrefix.length)}").text
-        }.mapError { NoSuchFileException(File(filename)) }
-    } else {
-        val sib = Path(source.origin).resolveSibling(filename)
-        if (sib.isRegularFile())
-            Ok(SourceCode.File(sib).text)
-        else
-            Ok(SourceCode.File(Path(filename)).text)
-    }
-}

codeGenCpu6502/src/prog8/codegen/cpu6502/ExpressionsAsmGen.kt

@@ -1,933 +0,0 @@
-package prog8.codegen.cpu6502
-
-import prog8.code.ast.*
-import prog8.code.core.*
-import kotlin.math.absoluteValue
-
-internal class ExpressionsAsmGen(private val program: PtProgram,
-                                 private val asmgen: AsmGen6502Internal,
-                                 private val allocator: VariableAllocator) {
-
-    @Deprecated("avoid calling this as it generates slow evalstack based code")
-    internal fun translateExpression(expression: PtExpression) {
-        if (this.asmgen.options.slowCodegenWarnings) {
-            asmgen.errors.warn("slow stack evaluation used for expression", expression.position)
-        }
-        translateExpressionInternal(expression)
-    }
-
-
-    // the rest of the methods are all PRIVATE
-
-
-    private fun translateExpressionInternal(expression: PtExpression) {
-
-        when(expression) {
-            is PtPrefix -> translateExpression(expression)
-            is PtBinaryExpression -> translateExpression(expression)
-            is PtArrayIndexer -> translateExpression(expression)
-            is PtTypeCast -> translateExpression(expression)
-            is PtAddressOf -> translateExpression(expression)
-            is PtMemoryByte -> asmgen.translateDirectMemReadExpressionToRegAorStack(expression, true)
-            is PtNumber -> translateExpression(expression)
-            is PtIdentifier -> translateExpression(expression)
-            is PtFunctionCall -> translateFunctionCallResultOntoStack(expression)
-            is PtBuiltinFunctionCall -> asmgen.translateBuiltinFunctionCallExpression(expression, true, null)
-            is PtContainmentCheck -> translateContainmentCheck(expression)
-            is PtArray, is PtString -> throw AssemblyError("string/array literal value assignment should have been replaced by a variable")
-            is PtRange -> throw AssemblyError("range expression should have been changed into array values")
-            is PtMachineRegister -> throw AssemblyError("machine register ast node should not occur in 6502 codegen it is for IR code")
-            else -> TODO("missing expression asmgen for $expression")
-        }
-    }
-
-    private fun translateContainmentCheck(check: PtContainmentCheck) {
-        asmgen.assignExpressionToRegister(check, RegisterOrPair.A)
-        asmgen.out("  sta  P8ESTACK_LO,x |  dex")
-    }
-
-    private fun translateFunctionCallResultOntoStack(call: PtFunctionCall) {
-        // only for use in nested expression evaluation
-
-        val symbol = asmgen.symbolTable.lookup(call.name)
-        val sub = symbol!!.astNode as IPtSubroutine
-        asmgen.saveXbeforeCall(call)
-        asmgen.translateFunctionCall(call)
-        if(sub.regXasResult()) {
-            // store the return value in X somewhere that we can access again below
-            asmgen.out("  stx  P8ZP_SCRATCH_REG")
-        }
-        asmgen.restoreXafterCall(call)
-
-        val returns: List<Pair<RegisterOrStatusflag, DataType>> = sub.returnsWhatWhere()
-        for ((reg, _) in returns) {
-            // result value is in cpu or status registers, put it on the stack instead (as we're evaluating an expression tree)
-            if (reg.registerOrPair != null) {
-                when (reg.registerOrPair!!) {
-                    RegisterOrPair.A -> asmgen.out("  sta  P8ESTACK_LO,x |  dex")
-                    RegisterOrPair.Y -> asmgen.out("  tya |  sta  P8ESTACK_LO,x |  dex")
-                    RegisterOrPair.AY -> asmgen.out("  sta  P8ESTACK_LO,x |  tya |  sta  P8ESTACK_HI,x |  dex")
-                    RegisterOrPair.X -> asmgen.out("  lda  P8ZP_SCRATCH_REG |  sta  P8ESTACK_LO,x |  dex")
-                    RegisterOrPair.AX -> asmgen.out("  sta  P8ESTACK_LO,x |  lda  P8ZP_SCRATCH_REG |  sta  P8ESTACK_HI,x |  dex")
-                    RegisterOrPair.XY -> asmgen.out("  tya |  sta  P8ESTACK_HI,x |  lda  P8ZP_SCRATCH_REG |  sta  P8ESTACK_LO,x |  dex")
-                    RegisterOrPair.FAC1 -> asmgen.out("  jsr  floats.push_fac1")
-                    RegisterOrPair.FAC2 -> asmgen.out("  jsr  floats.push_fac2")
-                    RegisterOrPair.R0,
-                    RegisterOrPair.R1,
-                    RegisterOrPair.R2,
-                    RegisterOrPair.R3,
-                    RegisterOrPair.R4,
-                    RegisterOrPair.R5,
-                    RegisterOrPair.R6,
-                    RegisterOrPair.R7,
-                    RegisterOrPair.R8,
-                    RegisterOrPair.R9,
-                    RegisterOrPair.R10,
-                    RegisterOrPair.R11,
-                    RegisterOrPair.R12,
-                    RegisterOrPair.R13,
-                    RegisterOrPair.R14,
-                    RegisterOrPair.R15 -> {
-                        asmgen.out(
-                            """
-                            lda  cx16.${reg.registerOrPair.toString().lowercase()}
-                            sta  P8ESTACK_LO,x
-                            lda  cx16.${reg.registerOrPair.toString().lowercase()}+1
-                            sta  P8ESTACK_HI,x
-                            dex
-                        """)
-                    }
-                }
-            } else when(reg.statusflag) {
-                Statusflag.Pc -> {
-                    asmgen.out("""
-                        lda  #0
-                        rol  a
-                        sta  P8ESTACK_LO,x
-                        dex""")
-                }
-                Statusflag.Pz -> {
-                    asmgen.out("""
-                        beq  +
-                        lda  #0
-                        beq  ++
-+                           lda  #1
-+                           sta  P8ESTACK_LO,x
-                        dex""")
-                }
-                Statusflag.Pv -> {
-                    asmgen.out("""
-                        bvs  +
-                        lda  #0
-                        beq  ++
-+                           lda  #1
-+                           sta  P8ESTACK_LO,x
-                        dex""")
-                }
-                Statusflag.Pn -> {
-                    asmgen.out("""
-                        bmi  +
-                        lda  #0
-                        beq  ++
-+                           lda  #1
-+                           sta  P8ESTACK_LO,x
-                        dex""")
-                }
-                null -> {}
-            }
-        }
-    }
-
-    private fun translateExpression(typecast: PtTypeCast) {
-        translateExpressionInternal(typecast.value)
-        when(typecast.value.type) {
-            DataType.UBYTE, DataType.BOOL -> {
-                when(typecast.type) {
-                    DataType.UBYTE, DataType.BYTE -> {}
-                    DataType.UWORD, DataType.WORD -> {
-                        if(asmgen.isTargetCpu(CpuType.CPU65c02))
-                            asmgen.out("  stz  P8ESTACK_HI+1,x")
-                        else
-                            asmgen.out("  lda  #0  |  sta  P8ESTACK_HI+1,x")
-                    }
-                    DataType.FLOAT -> asmgen.out(" jsr  floats.stack_ub2float")
-                    in PassByReferenceDatatypes -> throw AssemblyError("cannot cast to a pass-by-reference datatype")
-                    else -> throw AssemblyError("weird type")
-                }
-            }
-            DataType.BYTE -> {
-                when(typecast.type) {
-                    DataType.UBYTE, DataType.BYTE -> {}
-                    DataType.UWORD, DataType.WORD -> asmgen.signExtendStackLsb(DataType.BYTE)
-                    DataType.FLOAT -> asmgen.out(" jsr  floats.stack_b2float")
-                    in PassByReferenceDatatypes -> throw AssemblyError("cannot cast to a pass-by-reference datatype")
-                    else -> throw AssemblyError("weird type")
-                }
-            }
-            DataType.UWORD -> {
-                when(typecast.type) {
-                    DataType.BYTE, DataType.UBYTE -> {}
-                    DataType.WORD, DataType.UWORD -> {}
-                    DataType.FLOAT -> asmgen.out(" jsr  floats.stack_uw2float")
-                    in PassByReferenceDatatypes -> throw AssemblyError("cannot cast to a pass-by-reference datatype")
-                    else -> throw AssemblyError("weird type")
-                }
-            }
-            DataType.WORD -> {
-                when(typecast.type) {
-                    DataType.BYTE, DataType.UBYTE -> {}
-                    DataType.WORD, DataType.UWORD -> {}
-                    DataType.FLOAT -> asmgen.out(" jsr  floats.stack_w2float")
-                    in PassByReferenceDatatypes -> throw AssemblyError("cannot cast to a pass-by-reference datatype")
-                    else -> throw AssemblyError("weird type")
-                }
-            }
-            DataType.FLOAT -> {
-                when(typecast.type) {
-                    DataType.UBYTE -> asmgen.out(" jsr  floats.stack_float2uw")
-                    DataType.BYTE -> asmgen.out(" jsr  floats.stack_float2w")
-                    DataType.UWORD -> asmgen.out(" jsr  floats.stack_float2uw")
-                    DataType.WORD -> asmgen.out(" jsr  floats.stack_float2w")
-                    DataType.FLOAT -> {}
-                    in PassByReferenceDatatypes -> throw AssemblyError("cannot cast to a pass-by-reference datatype")
-                    else -> throw AssemblyError("weird type")
-                }
-            }
-            DataType.STR -> {
-                if (typecast.type != DataType.UWORD && typecast.type == DataType.STR)
-                    throw AssemblyError("cannot typecast a string into another incompatitble type")
-            }
-            in PassByReferenceDatatypes -> throw AssemblyError("cannot cast pass-by-reference value into another type")
-            else -> throw AssemblyError("weird type")
-        }
-    }
-
-    private fun translateExpression(expr: PtAddressOf) {
-        val name = asmgen.asmVariableName(expr.identifier)
-        asmgen.out("  lda  #<$name |  sta  P8ESTACK_LO,x |  lda  #>$name  |  sta  P8ESTACK_HI,x  | dex")
-    }
-
-    private fun translateExpression(expr: PtNumber) {
-        when(expr.type) {
-            DataType.UBYTE, DataType.BYTE -> asmgen.out(" lda  #${expr.number.toHex()}  | sta  P8ESTACK_LO,x  | dex")
-            DataType.UWORD, DataType.WORD -> asmgen.out("""
-                lda  #<${expr.number.toHex()}
-                sta  P8ESTACK_LO,x
-                lda  #>${expr.number.toHex()}
-                sta  P8ESTACK_HI,x
-                dex
-            """)
-            DataType.FLOAT -> {
-                val floatConst = allocator.getFloatAsmConst(expr.number)
-                asmgen.out(" lda  #<$floatConst |  ldy  #>$floatConst |  jsr  floats.push_float")
-            }
-            else -> throw AssemblyError("weird type")
-        }
-    }
-
-    private fun translateExpression(expr: PtIdentifier) {
-        val varname = asmgen.asmVariableName(expr)
-        when(expr.type) {
-            DataType.UBYTE, DataType.BYTE -> {
-                asmgen.out("  lda  $varname  |  sta  P8ESTACK_LO,x  |  dex")
-            }
-            DataType.UWORD, DataType.WORD -> {
-                asmgen.out("  lda  $varname  |  sta  P8ESTACK_LO,x  |  lda  $varname+1 |  sta  P8ESTACK_HI,x |  dex")
-            }
-            DataType.FLOAT -> {
-                asmgen.out(" lda  #<$varname |  ldy  #>$varname|  jsr  floats.push_float")
-            }
-            in SplitWordArrayTypes -> {
-                throw AssemblyError("can't push address of split-word array ${expr.position}")
-            }
-            in IterableDatatypes -> {
-                asmgen.out("  lda  #<$varname  |  sta  P8ESTACK_LO,x  |  lda  #>$varname |  sta  P8ESTACK_HI,x |  dex")
-            }
-            else -> throw AssemblyError("stack push weird variable type $expr")
-        }
-    }
-
-    private fun translateExpression(expr: PtBinaryExpression) {
-        // Uses evalstack to evaluate the given expression.  THIS IS SLOW AND SHOULD BE AVOIDED!
-        if(translateSomewhatOptimized(expr.left, expr.operator, expr.right))
-            return
-
-        val leftDt = expr.left.type
-        val rightDt = expr.right.type
-
-        // compare with zero
-        if(expr.operator in ComparisonOperators) {
-            if(leftDt in NumericDatatypes && rightDt in NumericDatatypes) {
-                val rightVal = expr.right.asConstInteger()
-                if(rightVal==0)
-                    return translateComparisonWithZero(expr.left, leftDt, expr.operator)
-            }
-        }
-
-        if(leftDt==DataType.STR && rightDt==DataType.STR && expr.operator in ComparisonOperators)
-            return translateCompareStrings(expr.left, expr.operator, 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")
-
-        // the general, non-optimized cases
-        // TODO optimize more cases.... (or one day just don't use the evalstack at all anymore)
-        translateExpressionInternal(expr.left)
-        translateExpressionInternal(expr.right)
-        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 translateSomewhatOptimized(left: PtExpression, operator: String, right: PtExpression): Boolean {
-        val leftDt = left.type
-        val rightDt = right.type
-        when(operator) {
-            "+" -> {
-                if(leftDt in IntegerDatatypes && rightDt in IntegerDatatypes) {
-                    val leftVal = left.asConstInteger()
-                    val rightVal = right.asConstInteger()
-                    if (leftVal!=null && leftVal in -4..4) {
-                        translateExpressionInternal(right)
-                        if(rightDt in ByteDatatypes) {
-                            val incdec = if(leftVal<0) "dec" else "inc"
-                            repeat(leftVal.absoluteValue) {
-                                asmgen.out("  $incdec  P8ESTACK_LO+1,x")
-                            }
-                        } else {
-                            // word
-                            if(leftVal<0) {
-                                repeat(leftVal.absoluteValue) {
-                                    asmgen.out("""
-                                        lda  P8ESTACK_LO+1,x
-                                        bne  +
-                                        dec  P8ESTACK_HI+1,x
-+                                       dec  P8ESTACK_LO+1,x""")
-                                }
-                            } else {
-                                repeat(leftVal) {
-                                    asmgen.out("""
-                                        inc  P8ESTACK_LO+1,x
-                                        bne  +
-                                        inc  P8ESTACK_HI+1,x
-+""")
-                                }
-                            }
-                        }
-                        return true
-                    }
-                    else if (rightVal!=null && rightVal in -4..4)
-                    {
-                        translateExpressionInternal(left)
-                        if(leftDt in ByteDatatypes) {
-                            val incdec = if(rightVal<0) "dec" else "inc"
-                            repeat(rightVal.absoluteValue) {
-                                asmgen.out("  $incdec  P8ESTACK_LO+1,x")
-                            }
-                        } else {
-                            // word
-                            if(rightVal<0) {
-                                repeat(rightVal.absoluteValue) {
-                                    asmgen.out("""
-                                        lda  P8ESTACK_LO+1,x
-                                        bne  +
-                                        dec  P8ESTACK_HI+1,x
-+                                       dec  P8ESTACK_LO+1,x""")
-                                }
-                            } else {
-                                repeat(rightVal) {
-                                    asmgen.out("""
-                                        inc  P8ESTACK_LO+1,x
-                                        bne  +
-                                        inc  P8ESTACK_HI+1,x
-+""")
-                                }
-                            }
-                        }
-                        return true
-                    }
-                }
-            }
-            "-" -> {
-                if(leftDt in IntegerDatatypes && rightDt in IntegerDatatypes) {
-                    val rightVal = right.asConstInteger()
-                    if (rightVal!=null && rightVal in -4..4)
-                    {
-                        translateExpressionInternal(left)
-                        if(leftDt in ByteDatatypes) {
-                            val incdec = if(rightVal<0) "inc" else "dec"
-                            repeat(rightVal.absoluteValue) {
-                                asmgen.out("  $incdec  P8ESTACK_LO+1,x")
-                            }
-                        } else {
-                            // word
-                            if(rightVal>0) {
-                                repeat(rightVal.absoluteValue) {
-                                    asmgen.out("""
-                                        lda  P8ESTACK_LO+1,x
-                                        bne  +
-                                        dec  P8ESTACK_HI+1,x
-+                                       dec  P8ESTACK_LO+1,x""")
-                                }
-                            } else {
-                                repeat(rightVal) {
-                                    asmgen.out("""
-                                        inc  P8ESTACK_LO+1,x
-                                        bne  +
-                                        inc  P8ESTACK_HI+1,x
-+""")
-                                }
-                            }
-                        }
-                        return true
-                    }
-                }
-            }
-            ">>" -> {
-                val amount = right.asConstInteger()
-                if(amount!=null) {
-                    translateExpressionInternal(left)
-                    when (leftDt) {
-                        DataType.UBYTE -> {
-                            if (amount <= 2)
-                                repeat(amount) { asmgen.out(" lsr  P8ESTACK_LO+1,x") }
-                            else {
-                                asmgen.out(" lda  P8ESTACK_LO+1,x")
-                                repeat(amount) { asmgen.out(" lsr  a") }
-                                asmgen.out(" sta  P8ESTACK_LO+1,x")
-                            }
-                        }
-                        DataType.BYTE -> {
-                            if (amount <= 2)
-                                repeat(amount) { asmgen.out(" lda  P8ESTACK_LO+1,x |  asl  a |  ror  P8ESTACK_LO+1,x") }
-                            else {
-                                asmgen.out(" lda  P8ESTACK_LO+1,x |  sta  P8ZP_SCRATCH_B1")
-                                repeat(amount) { asmgen.out(" asl  a |  ror  P8ZP_SCRATCH_B1 |  lda  P8ZP_SCRATCH_B1") }
-                                asmgen.out(" sta  P8ESTACK_LO+1,x")
-                            }
-                        }
-                        DataType.UWORD -> {
-                            if(amount>=16) {
-                                if(asmgen.isTargetCpu(CpuType.CPU65c02))
-                                    asmgen.out("  stz  P8ESTACK_LO+1,x |  stz  P8ESTACK_HI+1,x")
-                                else
-                                    asmgen.out("  lda  #0 |  sta  P8ESTACK_LO+1,x |  sta  P8ESTACK_HI+1,x")
-                                return true
-                            }
-                            var amountLeft = amount
-                            while (amountLeft >= 7) {
-                                asmgen.out(" jsr  math.shift_right_uw_7")
-                                amountLeft -= 7
-                            }
-                            if (amountLeft in 0..2)
-                                repeat(amountLeft) { asmgen.out(" lsr  P8ESTACK_HI+1,x |  ror  P8ESTACK_LO+1,x") }
-                            else
-                                asmgen.out(" jsr  math.shift_right_uw_$amountLeft")
-                        }
-                        DataType.WORD -> {
-                            if(amount>=16) {
-                                asmgen.out("""
-                                    lda  P8ESTACK_HI+1,x
-                                    bmi  +
-                                    lda  #0
-                                    sta  P8ESTACK_LO+1,x
-                                    sta  P8ESTACK_HI+1,x
-                                    beq  ++
-+                                   lda  #255
-                                    sta  P8ESTACK_LO+1,x
-                                    sta  P8ESTACK_HI+1,x
-+""")
-                                return true
-                            }
-                            var amountLeft = amount
-                            while (amountLeft >= 7) {
-                                asmgen.out(" jsr  math.shift_right_w_7")
-                                amountLeft -= 7
-                            }
-                            if (amountLeft in 0..2)
-                                repeat(amountLeft) { asmgen.out(" lda  P8ESTACK_HI+1,x |  asl  a  |  ror  P8ESTACK_HI+1,x |  ror  P8ESTACK_LO+1,x") }
-                            else
-                                asmgen.out(" jsr  math.shift_right_w_$amountLeft")
-                        }
-                        else -> throw AssemblyError("weird type")
-                    }
-                    return true
-                }
-            }
-            "<<" -> {
-                val amount = right.asConstInteger()
-                if(amount!=null) {
-                    translateExpressionInternal(left)
-                    if (leftDt in ByteDatatypes) {
-                        if (amount <= 2)
-                            repeat(amount) { asmgen.out("  asl  P8ESTACK_LO+1,x") }
-                        else {
-                            asmgen.out("  lda  P8ESTACK_LO+1,x")
-                            repeat(amount) { asmgen.out("  asl  a") }
-                            asmgen.out("  sta  P8ESTACK_LO+1,x")
-                        }
-                    } else {
-                        var amountLeft = amount
-                        while (amountLeft >= 7) {
-                            asmgen.out(" jsr  math.shift_left_w_7")
-                            amountLeft -= 7
-                        }
-                        if (amountLeft in 0..2)
-                            repeat(amountLeft) { asmgen.out("  asl  P8ESTACK_LO+1,x |  rol  P8ESTACK_HI+1,x") }
-                        else
-                            asmgen.out(" jsr  math.shift_left_w_$amountLeft")
-                    }
-                    return true
-                }
-            }
-            "*" -> {
-                if(leftDt in IntegerDatatypes && rightDt in IntegerDatatypes) {
-                    val leftVar = left as? PtIdentifier
-                    val rightVar = right as? PtIdentifier
-                    if(leftVar!=null && rightVar!=null && leftVar==rightVar) {
-                        translateSquared(leftVar, leftDt)
-                        return true
-                    }
-                }
-
-                val value = right as? PtNumber
-                if(value!=null) {
-                    if(rightDt in IntegerDatatypes) {
-                        val amount = value.number.toInt()
-                        if(amount==2) {
-                            // optimize x*2 common case
-                            translateExpressionInternal(left)
-                            if(leftDt in ByteDatatypes) {
-                                asmgen.out("  asl  P8ESTACK_LO+1,x")
-                            } else {
-                                asmgen.out("  asl  P8ESTACK_LO+1,x |  rol  P8ESTACK_HI+1,x")
-                            }
-                            return true
-                        }
-                        when(rightDt) {
-                            DataType.UBYTE -> {
-                                if(amount in asmgen.optimizedByteMultiplications) {
-                                    translateExpressionInternal(left)
-                                    asmgen.out(" jsr  math.stack_mul_byte_$amount")
-                                    return true
-                                }
-                            }
-                            DataType.BYTE -> {
-                                if(amount in asmgen.optimizedByteMultiplications) {
-                                    translateExpressionInternal(left)
-                                    asmgen.out(" jsr  math.stack_mul_byte_$amount")
-                                    return true
-                                }
-                                if(amount.absoluteValue in asmgen.optimizedByteMultiplications) {
-                                    translateExpressionInternal(left)
-                                    asmgen.out(" jsr  prog8_lib.neg_b |  jsr  math.stack_mul_byte_${amount.absoluteValue}")
-                                    return true
-                                }
-                            }
-                            DataType.UWORD -> {
-                                if(amount in asmgen.optimizedWordMultiplications) {
-                                    translateExpressionInternal(left)
-                                    asmgen.out(" jsr  math.stack_mul_word_$amount")
-                                    return true
-                                }
-                            }
-                            DataType.WORD -> {
-                                if(amount in asmgen.optimizedWordMultiplications) {
-                                    translateExpressionInternal(left)
-                                    asmgen.out(" jsr  math.stack_mul_word_$amount")
-                                    return true
-                                }
-                                if(amount.absoluteValue in asmgen.optimizedWordMultiplications) {
-                                    translateExpressionInternal(left)
-                                    asmgen.out(" jsr  prog8_lib.neg_w |  jsr  math.stack_mul_word_${amount.absoluteValue}")
-                                    return true
-                                }
-                            }
-                            else -> {}
-                        }
-                    }
-                }
-            }
-            "/" -> {
-                if(leftDt in IntegerDatatypes && rightDt in IntegerDatatypes) {
-                    val rightVal = right.asConstInteger()
-                    if(rightVal!=null && rightVal==2) {
-                        translateExpressionInternal(left)
-                        when (leftDt) {
-                            DataType.UBYTE -> {
-                                asmgen.out("  lsr  P8ESTACK_LO+1,x")
-                            }
-                            DataType.UWORD -> {
-                                asmgen.out("  lsr  P8ESTACK_HI+1,x |  ror  P8ESTACK_LO+1,x")
-                            }
-                            DataType.BYTE -> {
-                                // signed divide using shift needs adjusting of negative value to get correct rounding towards zero
-                                asmgen.out("""
-                                    lda  P8ESTACK_LO+1,x
-                                    bpl  +
-                                    inc  P8ESTACK_LO+1,x
-                                    lda  P8ESTACK_LO+1,x
-+                                   asl  a
-                                    ror  P8ESTACK_LO+1,x""")
-                            }
-                            DataType.WORD -> {
-                                // signed divide using shift needs adjusting of negative value to get correct rounding towards zero
-                                asmgen.out("""
-                                    lda  P8ESTACK_HI+1,x
-                                    bpl  ++
-                                    inc  P8ESTACK_LO+1,x
-                                    bne  +
-                                    inc  P8ESTACK_HI+1,x
-+                                   lda  P8ESTACK_HI+1,x
-+                                   asl  a
-                                    ror  P8ESTACK_HI+1,x
-                                    ror  P8ESTACK_LO+1,x""")
-                            }
-                            else -> throw AssemblyError("weird dt")
-                        }
-                        return true
-                    }
-                }
-            }
-        }
-
-        return false
-    }
-
-    private fun translateComparisonWithZero(expr: PtExpression, dt: DataType, operator: String) {
-        if(expr.isSimple()) {
-            if(operator=="!=") {
-                when (dt) {
-                    in ByteDatatypes -> {
-                        asmgen.assignExpressionToRegister(expr, RegisterOrPair.A, dt == DataType.BYTE)
-                        asmgen.out("""
-                            beq  +
-                            lda  #1
-+                           sta  P8ESTACK_LO,x
-                            dex""")
-                        return
-                    }
-                    in WordDatatypes -> {
-                        asmgen.assignExpressionToRegister(expr, RegisterOrPair.AY, dt == DataType.WORD)
-                        asmgen.out("""
-                            sty  P8ZP_SCRATCH_B1 
-                            ora  P8ZP_SCRATCH_B1
-                            beq  +
-                            lda  #1
-+                           sta  P8ESTACK_LO,x
-                            dex""")
-                        return
-                    }
-                    DataType.FLOAT -> {
-                        asmgen.assignExpressionToRegister(expr, RegisterOrPair.FAC1, true)
-                        asmgen.out("""
-                            jsr  floats.SIGN
-                            sta  P8ESTACK_LO,x
-                            dex""")
-                        return
-                    }
-                    else -> {}
-                }
-            }
-            /* operator == is not worth it to special case, the code is mostly larger */
-        }
-        translateExpressionInternal(expr)
-        when(operator) {
-            "==" -> {
-                when(dt) {
-                    DataType.UBYTE, DataType.BYTE -> asmgen.out("  jsr  prog8_lib.equalzero_b")
-                    DataType.UWORD, DataType.WORD -> asmgen.out("  jsr  prog8_lib.equalzero_w")
-                    DataType.FLOAT -> asmgen.out("  jsr  floats.equal_zero")
-                    else -> throw AssemblyError("wrong dt")
-                }
-            }
-            "!=" -> {
-                when(dt) {
-                    DataType.UBYTE, DataType.BYTE -> asmgen.out("  jsr  prog8_lib.notequalzero_b")
-                    DataType.UWORD, DataType.WORD -> asmgen.out("  jsr  prog8_lib.notequalzero_w")
-                    DataType.FLOAT -> asmgen.out("  jsr  floats.notequal_zero")
-                    else -> throw AssemblyError("wrong dt")
-                }
-            }
-            "<" -> {
-                if(dt==DataType.UBYTE || dt==DataType.UWORD)
-                    return translateExpressionInternal(PtNumber.fromBoolean(false, expr.position))
-                when(dt) {
-                    DataType.BYTE -> asmgen.out("  jsr  prog8_lib.lesszero_b")
-                    DataType.WORD -> asmgen.out("  jsr  prog8_lib.lesszero_w")
-                    DataType.FLOAT -> asmgen.out("  jsr  floats.less_zero")
-                    else -> throw AssemblyError("wrong dt")
-                }
-            }
-            ">" -> {
-                when(dt) {
-                    DataType.UBYTE -> asmgen.out("  jsr  prog8_lib.greaterzero_ub")
-                    DataType.BYTE -> asmgen.out("  jsr  prog8_lib.greaterzero_sb")
-                    DataType.UWORD -> asmgen.out("  jsr  prog8_lib.greaterzero_uw")
-                    DataType.WORD -> asmgen.out("  jsr  prog8_lib.greaterzero_sw")
-                    DataType.FLOAT -> asmgen.out("  jsr  floats.greater_zero")
-                    else -> throw AssemblyError("wrong dt")
-                }
-            }
-            "<=" -> {
-                when(dt) {
-                    DataType.UBYTE -> asmgen.out("  jsr  prog8_lib.equalzero_b")
-                    DataType.BYTE -> asmgen.out("  jsr  prog8_lib.lessequalzero_sb")
-                    DataType.UWORD -> asmgen.out("  jsr  prog8_lib.equalzero_w")
-                    DataType.WORD -> asmgen.out("  jsr  prog8_lib.lessequalzero_sw")
-                    DataType.FLOAT -> asmgen.out("  jsr  floats.lessequal_zero")
-                    else -> throw AssemblyError("wrong dt")
-                }
-            }
-            ">=" -> {
-                if(dt==DataType.UBYTE || dt==DataType.UWORD)
-                    return translateExpressionInternal(PtNumber.fromBoolean(true, expr.position))
-                when(dt) {
-                    DataType.BYTE -> asmgen.out("  jsr  prog8_lib.greaterequalzero_sb")
-                    DataType.WORD -> asmgen.out("  jsr  prog8_lib.greaterequalzero_sw")
-                    DataType.FLOAT -> asmgen.out("  jsr  floats.greaterequal_zero")
-                    else -> throw AssemblyError("wrong dt")
-                }
-            }
-            else -> throw AssemblyError("invalid comparison operator")
-        }
-    }
-
-    private fun translateSquared(variable: PtIdentifier, dt: DataType) {
-        val asmVar = asmgen.asmVariableName(variable)
-        when(dt) {
-            DataType.BYTE, DataType.UBYTE -> {
-                asmgen.out("  lda  $asmVar")
-                asmgen.signExtendAYlsb(dt)
-                asmgen.out("  jsr  math.square")
-            }
-            DataType.UWORD, DataType.WORD -> {
-                asmgen.out("  lda  $asmVar |  ldy  $asmVar+1 |  jsr  math.square")
-            }
-            else -> throw AssemblyError("require integer dt for square")
-        }
-        asmgen.out("  sta  P8ESTACK_LO,x |  tya |  sta  P8ESTACK_HI,x |  dex")
-    }
-
-    private fun translateExpression(expr: PtPrefix) {
-        translateExpressionInternal(expr.value)
-        when(expr.operator) {
-            "+" -> {}
-            "-" -> {
-                when(expr.type) {
-                    in ByteDatatypes -> asmgen.out("  jsr  prog8_lib.neg_b")
-                    in WordDatatypes -> asmgen.out("  jsr  prog8_lib.neg_w")
-                    DataType.FLOAT -> asmgen.out("  jsr  floats.neg_f")
-                    else -> throw AssemblyError("weird type")
-                }
-            }
-            "~" -> {
-                when(expr.type) {
-                    in ByteDatatypes ->
-                        asmgen.out("""
-                            lda  P8ESTACK_LO+1,x
-                            eor  #255
-                            sta  P8ESTACK_LO+1,x
-                            """)
-                    in WordDatatypes -> asmgen.out("  jsr  prog8_lib.inv_word")
-                    else -> throw AssemblyError("weird type")
-                }
-            }
-            else -> throw AssemblyError("invalid prefix operator ${expr.operator}")
-        }
-    }
-
-    private fun translateExpression(arrayExpr: PtArrayIndexer) {
-        val elementDt = arrayExpr.type
-        val arrayVarName = asmgen.asmVariableName(arrayExpr.variable)
-
-        if(arrayExpr.variable.type==DataType.UWORD) {
-            // indexing a pointer var instead of a real array or string
-            if(elementDt !in ByteDatatypes)
-                throw AssemblyError("non-array var indexing requires bytes dt")
-            if(arrayExpr.index.type != DataType.UBYTE)
-                throw AssemblyError("non-array var indexing requires bytes index")
-            asmgen.loadScaledArrayIndexIntoRegister(arrayExpr, elementDt, CpuRegister.Y)
-            if(asmgen.isZpVar(arrayExpr.variable)) {
-                asmgen.out("  lda  ($arrayVarName),y")
-            } else {
-                asmgen.out("  lda  $arrayVarName |  sta  P8ZP_SCRATCH_W1 |  lda  $arrayVarName+1 |  sta  P8ZP_SCRATCH_W1+1")
-                asmgen.out("  lda  (P8ZP_SCRATCH_W1),y")
-            }
-            asmgen.out("  sta  P8ESTACK_LO,x |  dex")
-            return
-        }
-
-        if(arrayExpr.splitWords)
-            TODO("split words expression ${arrayExpr.position}")
-
-        val constIndexNum = arrayExpr.index.asConstInteger()
-        if(constIndexNum!=null) {
-            val indexValue = constIndexNum * program.memsizer.memorySize(elementDt)
-            when(elementDt) {
-                in ByteDatatypes -> {
-                    asmgen.out("  lda  $arrayVarName+$indexValue |  sta  P8ESTACK_LO,x |  dex")
-                }
-                in WordDatatypes -> {
-                    asmgen.out("  lda  $arrayVarName+$indexValue |  sta  P8ESTACK_LO,x |  lda  $arrayVarName+$indexValue+1 |  sta  P8ESTACK_HI,x |  dex")
-                }
-                DataType.FLOAT -> {
-                    asmgen.out("  lda  #<($arrayVarName+$indexValue) |  ldy  #>($arrayVarName+$indexValue) |  jsr  floats.push_float")
-                }
-                else -> throw AssemblyError("weird element type")
-            }
-        } else {
-            when(elementDt) {
-                in ByteDatatypes -> {
-                    asmgen.loadScaledArrayIndexIntoRegister(arrayExpr, elementDt, CpuRegister.Y)
-                    asmgen.out(" lda  $arrayVarName,y |  sta  P8ESTACK_LO,x |  dex")
-                }
-                in WordDatatypes -> {
-                    asmgen.loadScaledArrayIndexIntoRegister(arrayExpr, elementDt, CpuRegister.Y)
-                    asmgen.out(" lda  $arrayVarName,y |  sta  P8ESTACK_LO,x |  lda  $arrayVarName+1,y |  sta  P8ESTACK_HI,x |  dex")
-                }
-                DataType.FLOAT -> {
-                    asmgen.loadScaledArrayIndexIntoRegister(arrayExpr, elementDt, CpuRegister.A)
-                    asmgen.out("""
-                        ldy  #>$arrayVarName
-                        clc
-                        adc  #<$arrayVarName
-                        bcc  +
-                        iny
-+                       jsr  floats.push_float""")
-                }
-                else -> throw AssemblyError("weird dt")
-            }
-
-        }
-    }
-
-    private fun translateBinaryOperatorBytes(operator: String, types: DataType) {
-        when(operator) {
-            "*" -> 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  P8ESTACK_LO+2,x
-                clc
-                adc  P8ESTACK_LO+1,x
-                inx
-                sta  P8ESTACK_LO+1,x
-                """)
-            "-" -> asmgen.out("""
-                lda  P8ESTACK_LO+2,x
-                sec
-                sbc  P8ESTACK_LO+1,x
-                inx
-                sta  P8ESTACK_LO+1,x
-                """)
-            "<<" -> asmgen.out("  jsr  prog8_lib.shiftleft_b")
-            ">>" -> asmgen.out("  jsr  prog8_lib.shiftright_b")
-            "<" -> 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")
-            else -> throw AssemblyError("invalid operator $operator")
-        }
-    }
-
-    private fun translateBinaryOperatorWords(operator: String, dt: DataType) {
-        when(operator) {
-            "*" -> asmgen.out("  jsr  prog8_lib.mul_word")
-            "/" -> asmgen.out(if(dt==DataType.UWORD) "  jsr  prog8_lib.idiv_uw" else "  jsr  prog8_lib.idiv_w")
-            "%" -> {
-                if(dt==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")
-            "<<" -> asmgen.out("  jsr  math.shift_left_w")
-            ">>" -> {
-                if(dt==DataType.UWORD)
-                    asmgen.out("  jsr  math.shift_right_uw")
-                else
-                    asmgen.out("  jsr  math.shift_right_w")
-            }
-            "<" -> asmgen.out(if(dt==DataType.UWORD) "  jsr  prog8_lib.less_uw" else "  jsr  prog8_lib.less_w")
-            ">" -> asmgen.out(if(dt==DataType.UWORD) "  jsr  prog8_lib.greater_uw" else "  jsr  prog8_lib.greater_w")
-            "<=" -> asmgen.out(if(dt==DataType.UWORD) "  jsr  prog8_lib.lesseq_uw" else "  jsr  prog8_lib.lesseq_w")
-            ">=" -> asmgen.out(if(dt==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")
-            else -> throw AssemblyError("invalid operator $operator")
-        }
-    }
-
-    private fun translateBinaryOperatorFloats(operator: String) {
-        when(operator) {
-            "*" -> asmgen.out("  jsr  floats.mul_f")
-            "/" -> asmgen.out("  jsr  floats.div_f")
-            "+" -> asmgen.out("  jsr  floats.add_f")
-            "-" -> asmgen.out("  jsr  floats.sub_f")
-            "<" -> asmgen.out("  jsr  floats.less_f")
-            ">" -> asmgen.out("  jsr  floats.greater_f")
-            "<=" -> asmgen.out("  jsr  floats.lesseq_f")
-            ">=" -> asmgen.out("  jsr  floats.greatereq_f")
-            "==" -> asmgen.out("  jsr  floats.equal_f")
-            "!=" -> asmgen.out("  jsr  floats.notequal_f")
-            "%", "<<", ">>", "&", "^", "|" -> throw AssemblyError("requires integer datatype")
-            else -> throw AssemblyError("invalid operator $operator")
-        }
-    }
-
-    private fun translateCompareStrings(s1: PtExpression, operator: String, s2: PtExpression) {
-        asmgen.assignExpressionToVariable(s1, "prog8_lib.strcmp_expression._arg_s1", DataType.UWORD)
-        asmgen.assignExpressionToVariable(s2, "prog8_lib.strcmp_expression._arg_s2", DataType.UWORD)
-        asmgen.out(" jsr  prog8_lib.strcmp_expression")    // result  of compare is in A
-        compareStringsProcessResultInA(operator)
-    }
-
-    private fun compareStringsProcessResultInA(operator: String) {
-        when(operator) {
-            "==" -> asmgen.out(" and  #1 |  eor  #1 |  sta  P8ESTACK_LO,x")
-            "!=" -> asmgen.out(" and  #1 |  sta  P8ESTACK_LO,x")
-            "<=" -> asmgen.out("""
-                bpl  +
-                lda  #1
-                bne  ++
-+               lda  #0
-+               sta  P8ESTACK_LO,x""")
-            ">=" -> asmgen.out("""
-                bmi  +
-                lda  #1
-                bne  ++
-+               lda  #0
-+               sta  P8ESTACK_LO,x""")
-            "<" -> asmgen.out("""
-                bmi  +
-                lda  #0
-                beq  ++
-+               lda  #1
-+               sta  P8ESTACK_LO,x""")
-            ">" -> asmgen.out("""
-                bpl  +
-                lda  #0
-                beq  ++
-+               lda  #1
-+               sta  P8ESTACK_LO,x""")
-        }
-        asmgen.out("  dex")
-    }
-}

codeGenCpu6502/src/prog8/codegen/cpu6502/Extensions.kt

@@ -6,26 +6,6 @@ import prog8.code.ast.PtSub
 import prog8.code.core.*
 
 
-internal fun IPtSubroutine.regXasResult(): Boolean =
-    (this is PtAsmSub) && this.returns.any { it.first.registerOrPair in arrayOf(RegisterOrPair.X, RegisterOrPair.AX, RegisterOrPair.XY) }
-
-internal fun IPtSubroutine.shouldSaveX(): Boolean =
-    this.regXasResult() || (this is PtAsmSub && (CpuRegister.X in this.clobbers || regXasParam()))
-
-internal fun PtAsmSub.regXasParam(): Boolean =
-    parameters.any { it.first.registerOrPair in arrayOf(RegisterOrPair.X, RegisterOrPair.AX, RegisterOrPair.XY) }
-
-internal class KeepAresult(val saveOnEntry: Boolean, val saveOnReturn: Boolean)
-
-internal fun PtAsmSub.shouldKeepA(): KeepAresult {
-    // determine if A's value should be kept when preparing for calling the subroutine, and when returning from it
-
-    // it seems that we never have to save A when calling? will be loaded correctly after setup.
-    // but on return it depends on wether the routine returns something in A.
-    val saveAonReturn = returns.any { it.first.registerOrPair==RegisterOrPair.A || it.first.registerOrPair==RegisterOrPair.AY || it.first.registerOrPair==RegisterOrPair.AX }
-    return KeepAresult(false, saveAonReturn)
-}
-
 internal fun IPtSubroutine.returnsWhatWhere(): List<Pair<RegisterOrStatusflag, DataType>> {
     when(this) {
         is PtAsmSub -> {

codeGenCpu6502/src/prog8/codegen/cpu6502/ForLoopsAsmGen.kt

@@ -5,9 +5,10 @@ import prog8.code.ast.*
 import prog8.code.core.*
 import kotlin.math.absoluteValue
 
-internal class ForLoopsAsmGen(private val program: PtProgram,
-                              private val asmgen: AsmGen6502Internal,
-                              private val zeropage: Zeropage) {
+internal class ForLoopsAsmGen(
+    private val asmgen: AsmGen6502Internal,
+    private val zeropage: Zeropage
+) {
 
     internal fun translate(stmt: PtForLoop) {
         val iterableDt = stmt.iterable.type
@@ -254,11 +255,11 @@ $loopLabel""")
                 sec
                 sbc  #<${stepsize.absoluteValue}
                 sta  $varname
-                pha
+                tax
                 lda  $varname+1
                 sbc  #>${stepsize.absoluteValue}
                 sta  $varname+1
-                pla
+                txa
 $modifiedLabel2 cmp  #0    ; modified 
                 lda  $varname+1
 $modifiedLabel  sbc  #0    ; modified
@@ -382,7 +383,7 @@ $loopLabel          sty  $indexVar
                     // allocate index var on ZP if possible
                     val result = zeropage.allocate(indexVar, DataType.UBYTE, null, stmt.position, asmgen.errors)
                     result.fold(
-                        success = { (address,_)-> asmgen.out("""$indexVar = $address  ; auto zp UBYTE""") },
+                        success = { (address, _, _)-> asmgen.out("""$indexVar = $address  ; auto zp UBYTE""") },
                         failure = { asmgen.out("$indexVar    .byte  0") }
                     )
                 } else {

codeGenCpu6502/src/prog8/codegen/cpu6502/FunctionCallAsmGen.kt

@@ -11,42 +11,10 @@ import prog8.codegen.cpu6502.assignment.TargetStorageKind
 internal class FunctionCallAsmGen(private val program: PtProgram, private val asmgen: AsmGen6502Internal) {
 
     internal fun translateFunctionCallStatement(stmt: PtFunctionCall) {
-        saveXbeforeCall(stmt)
         translateFunctionCall(stmt)
-        restoreXafterCall(stmt)
         // just ignore any result values from the function call.
     }
 
-    internal fun saveXbeforeCall(stmt: PtFunctionCall) {
-        val symbol = asmgen.symbolTable.lookup(stmt.name)
-        val sub = symbol!!.astNode as IPtSubroutine
-        if(sub.shouldSaveX()) {
-            if(sub is PtAsmSub) {
-                val regSaveOnStack = sub.address == null       // rom-routines don't require registers to be saved on stack, normal subroutines do because they can contain nested calls
-                if (regSaveOnStack)
-                    asmgen.saveRegisterStack(CpuRegister.X, sub.shouldKeepA().saveOnEntry)
-                else
-                    asmgen.saveRegisterLocal(CpuRegister.X, stmt.definingISub()!!)
-            } else
-                asmgen.saveRegisterLocal(CpuRegister.X, stmt.definingISub()!!)
-        }
-    }
-
-    internal fun restoreXafterCall(stmt: PtFunctionCall) {
-        val symbol = asmgen.symbolTable.lookup(stmt.name)
-        val sub = symbol!!.astNode as IPtSubroutine
-        if(sub.shouldSaveX()) {
-            if(sub is PtAsmSub) {
-                val regSaveOnStack = sub.address == null       // rom-routines don't require registers to be saved on stack, normal subroutines do because they can contain nested calls
-                if (regSaveOnStack)
-                    asmgen.restoreRegisterStack(CpuRegister.X, sub.shouldKeepA().saveOnReturn)
-                else
-                    asmgen.restoreRegisterLocal(CpuRegister.X)
-            } else
-                asmgen.restoreRegisterLocal(CpuRegister.X)
-        }
-    }
-
     internal fun optimizeIntArgsViaRegisters(sub: PtSub) =
         (sub.parameters.size==1 && sub.parameters[0].type in IntegerDatatypes)
                 || (sub.parameters.size==2 && sub.parameters[0].type in ByteDatatypes && sub.parameters[1].type in ByteDatatypes)
@@ -63,8 +31,8 @@ internal class FunctionCallAsmGen(private val program: PtProgram, private val as
 
         if(sub is PtAsmSub) {
             argumentsViaRegisters(sub, call)
-            if (sub.inline && asmgen.options.optimize) {
-                // inline the subroutine.
+            if (sub.inline) {
+                // inline the subroutine. (regardless of optimization settings!)
                 // we do this by copying the subroutine's statements at the call site.
                 // NOTE: *if* there is a return statement, it will be the only one, and the very last statement of the subroutine
                 // (this condition has been enforced by an ast check earlier)
@@ -101,37 +69,59 @@ internal class FunctionCallAsmGen(private val program: PtProgram, private val as
         // remember: dealing with the X register and/or dealing with return values is the responsibility of the caller
     }
 
-    private fun argumentsViaRegisters(sub: PtAsmSub, call: PtFunctionCall) {
-        if(sub.parameters.size==1) {
-            argumentViaRegister(sub, IndexedValue(0, sub.parameters.single().second), call.args[0])
-        } else {
-            if(asmsub6502ArgsHaveRegisterClobberRisk(call.args, sub.parameters)) {
-                registerArgsViaCpuStackEvaluation(call, sub)
-            } else {
-                asmsub6502ArgsEvalOrder(sub).forEach {
-                    val param = sub.parameters[it]
-                    val arg = call.args[it]
-                    argumentViaRegister(sub, IndexedValue(it, param.second), arg)
-                }
+
+    private fun usesOtherRegistersWhileEvaluating(arg: PtExpression): Boolean {
+        return when(arg) {
+            is PtBuiltinFunctionCall -> {
+                if (arg.name == "lsb" || arg.name == "msb")
+                    return usesOtherRegistersWhileEvaluating(arg.args[0])
+                if (arg.name == "mkword")
+                    return usesOtherRegistersWhileEvaluating(arg.args[0]) || usesOtherRegistersWhileEvaluating(arg.args[1])
+                return !arg.isSimple()
             }
+            is PtAddressOf -> false
+            is PtIdentifier -> false
+            is PtMachineRegister -> false
+            is PtMemoryByte -> false
+            is PtNumber -> false
+            else -> true
         }
     }
 
-    private fun registerArgsViaCpuStackEvaluation(call: PtFunctionCall, callee: PtAsmSub) {
-        // this is called when one or more of the arguments are 'complex' and
-        // cannot be assigned to a register easily or risk clobbering other registers.
+    private fun argumentsViaRegisters(sub: PtAsmSub, call: PtFunctionCall) {
+        val registersUsed = mutableListOf<RegisterOrStatusflag>();
 
-        if(callee.parameters.isEmpty())
-            return
+        fun usedA() = registersUsed.any {it.registerOrPair==RegisterOrPair.A || it.registerOrPair==RegisterOrPair.AX || it.registerOrPair==RegisterOrPair.AY}
+        fun usedX() = registersUsed.any {it.registerOrPair==RegisterOrPair.X || it.registerOrPair==RegisterOrPair.AX || it.registerOrPair==RegisterOrPair.XY}
+        fun usedY() = registersUsed.any {it.registerOrPair==RegisterOrPair.Y || it.registerOrPair==RegisterOrPair.AY || it.registerOrPair==RegisterOrPair.XY}
 
-        // use the cpu hardware stack as intermediate storage for the arguments.
-        val argOrder = asmsub6502ArgsEvalOrder(callee)
-        argOrder.reversed().forEach {
-            asmgen.pushCpuStack(callee.parameters[it].second.type, call.args[it])
-        }
-        argOrder.forEach {
-            val param = callee.parameters[it]
-            asmgen.popCpuStack(callee, param.second, param.first)
+        if(sub.parameters.size==1) {
+            argumentViaRegister(sub, IndexedValue(0, sub.parameters.single().second), call.args[0])
+        } else {
+            val optimalEvalOrder = asmsub6502ArgsEvalOrder(sub)
+            optimalEvalOrder.forEach {
+                val param = sub.parameters[it]
+                val arg = call.args[it]
+                registersUsed += if(usesOtherRegistersWhileEvaluating(arg)) {
+                    if(!registersUsed.any{it.statusflag!=null || it.registerOrPair in CpuRegisters})
+                        argumentViaRegister(sub, IndexedValue(it, param.second), arg)
+                    else if(registersUsed.any {it.statusflag!=null}) {
+                        throw AssemblyError("call argument evaluation problem: can't save cpu statusregister parameter ${call.position}")
+                    }
+                    else {
+                        if(usedX()) asmgen.saveRegisterStack(CpuRegister.X, false)
+                        if(usedY()) asmgen.saveRegisterStack(CpuRegister.Y, false)
+                        if(usedA()) asmgen.saveRegisterStack(CpuRegister.A, false)
+                        val used = argumentViaRegister(sub, IndexedValue(it, param.second), arg)
+                        if(usedA()) asmgen.restoreRegisterStack(CpuRegister.A, false)
+                        if(usedY()) asmgen.restoreRegisterStack(CpuRegister.Y, true)
+                        if(usedX()) asmgen.restoreRegisterStack(CpuRegister.X, true)
+                        used
+                    }
+                } else {
+                    argumentViaRegister(sub, IndexedValue(it, param.second), arg)
+                }
+            }
         }
     }
 
@@ -144,7 +134,7 @@ internal class FunctionCallAsmGen(private val program: PtProgram, private val as
         asmgen.assignExpressionToVariable(value, varName, parameter.type)
     }
 
-    private fun argumentViaRegister(sub: IPtSubroutine, parameter: IndexedValue<PtSubroutineParameter>, value: PtExpression, registerOverride: RegisterOrPair? = null) {
+    private fun argumentViaRegister(sub: IPtSubroutine, parameter: IndexedValue<PtSubroutineParameter>, value: PtExpression, registerOverride: RegisterOrPair? = null): RegisterOrStatusflag {
         // pass argument via a register parameter
         if(!isArgumentTypeCompatible(value.type, parameter.value.type))
             throw AssemblyError("argument type incompatible")
@@ -173,6 +163,7 @@ internal class FunctionCallAsmGen(private val program: PtProgram, private val as
                     }
                     is PtIdentifier -> {
                         val sourceName = asmgen.asmVariableName(value)
+                        // note: cannot use X register here to store A because it might be used for other arguments
                         asmgen.out("""
                             pha
                             clc
@@ -187,6 +178,7 @@ internal class FunctionCallAsmGen(private val program: PtProgram, private val as
                     }
                 }
             } else throw AssemblyError("can only use Carry as status flag parameter")
+            return RegisterOrStatusflag(null, statusflag)
         }
         else {
             // via register or register pair
@@ -219,6 +211,7 @@ internal class FunctionCallAsmGen(private val program: PtProgram, private val as
                 }
                 asmgen.translateNormalAssignment(AsmAssignment(src, target, program.memsizer, Position.DUMMY), scope)
             }
+            return RegisterOrStatusflag(register, null)
         }
     }
 
@@ -240,3 +233,5 @@ internal class FunctionCallAsmGen(private val program: PtProgram, private val as
         return false
     }
 }
+
+

codeGenCpu6502/src/prog8/codegen/cpu6502/PostIncrDecrAsmGen.kt

@@ -13,7 +13,6 @@ internal class PostIncrDecrAsmGen(private val program: PtProgram, private val as
         val targetIdent = stmt.target.identifier
         val targetMemory = stmt.target.memory
         val targetArrayIdx = stmt.target.array
-        val scope = stmt.definingISub()
         when {
             targetIdent!=null -> {
                 val what = asmgen.asmVariableName(targetIdent)
@@ -76,7 +75,6 @@ internal class PostIncrDecrAsmGen(private val program: PtProgram, private val as
         dec  ${asmArrayvarname}_msb+$constIndex
 +       dec  ${asmArrayvarname}_lsb+$constIndex""")
                     } else {
-                        asmgen.saveRegisterLocal(CpuRegister.X, scope!!)
                         asmgen.loadScaledArrayIndexIntoRegister(targetArrayIdx, elementDt, CpuRegister.X)
                         if(incr)
                             asmgen.out(" inc  ${asmArrayvarname}_lsb,x |  bne  + |  inc  ${asmArrayvarname}_msb,x |+")
@@ -86,14 +84,30 @@ internal class PostIncrDecrAsmGen(private val program: PtProgram, private val as
         bne  +
         dec  ${asmArrayvarname}_msb,x
 +       dec  ${asmArrayvarname}_lsb,x""")
-                        asmgen.restoreRegisterLocal(CpuRegister.X)
                     }
                     return
                 }
                 if(constIndex!=null) {
                     val indexValue = constIndex * program.memsizer.memorySize(elementDt)
                     when(elementDt) {
-                        in ByteDatatypes -> asmgen.out(if (incr) "  inc  $asmArrayvarname+$indexValue" else "  dec  $asmArrayvarname+$indexValue")
+                        in ByteDatatypes -> {
+                            if(targetArrayIdx.usesPointerVariable) {
+                                asmgen.out("""
+                                    lda  $asmArrayvarname
+                                    clc
+                                    adc  #$indexValue
+                                    sta  (+) +1
+                                    lda  $asmArrayvarname+1
+                                    adc  #0
+                                    sta  (+) +2""")
+                                if(incr)
+                                    asmgen.out("+\tinc  ${'$'}ffff\t; modified")
+                                else
+                                    asmgen.out("+\tdec  ${'$'}ffff\t; modified")
+                            } else {
+                                asmgen.out(if (incr) "  inc  $asmArrayvarname+$indexValue" else "  dec  $asmArrayvarname+$indexValue")
+                            }
+                        }
                         in WordDatatypes -> {
                             if(incr)
                                 asmgen.out(" inc  $asmArrayvarname+$indexValue |  bne  + |  inc  $asmArrayvarname+$indexValue+1 |+")
@@ -113,11 +127,25 @@ internal class PostIncrDecrAsmGen(private val program: PtProgram, private val as
                 }
                 else
                 {
-                    asmgen.saveRegisterLocal(CpuRegister.X, scope!!)
                     asmgen.loadScaledArrayIndexIntoRegister(targetArrayIdx, elementDt, CpuRegister.X)
                     when(elementDt) {
                         in ByteDatatypes -> {
-                            asmgen.out(if(incr) "  inc  $asmArrayvarname,x" else "  dec  $asmArrayvarname,x")
+                            if(targetArrayIdx.usesPointerVariable) {
+                                asmgen.out("""
+                                    txa
+                                    clc
+                                    adc  $asmArrayvarname
+                                    sta  (+) +1
+                                    lda  $asmArrayvarname+1
+                                    adc  #0
+                                    sta  (+) +2""")
+                                if(incr)
+                                    asmgen.out("+\tinc  ${'$'}ffff\t; modified")
+                                else
+                                    asmgen.out("+\tdec  ${'$'}ffff\t; modified")
+                            } else {
+                                asmgen.out(if (incr) "  inc  $asmArrayvarname,x" else "  dec  $asmArrayvarname,x")
+                            }
                         }
                         in WordDatatypes -> {
                             if(incr)
@@ -127,8 +155,7 @@ internal class PostIncrDecrAsmGen(private val program: PtProgram, private val as
         lda  $asmArrayvarname,x
         bne  +
         dec  $asmArrayvarname+1,x
-+       dec  $asmArrayvarname,x 
-""")
++       dec  $asmArrayvarname,x""")
                         }
                         DataType.FLOAT -> {
                             asmgen.out("""
@@ -141,7 +168,6 @@ internal class PostIncrDecrAsmGen(private val program: PtProgram, private val as
                         }
                         else -> throw AssemblyError("weird array elt dt")
                     }
-                    asmgen.restoreRegisterLocal(CpuRegister.X)
                 }
             }
         }

codeGenCpu6502/src/prog8/codegen/cpu6502/ProgramAndVarsGen.kt

@@ -75,8 +75,6 @@ internal class ProgramAndVarsGen(
         asmgen.out("P8ZP_SCRATCH_W1 = ${zp.SCRATCH_W1}    ; word")
         asmgen.out("P8ZP_SCRATCH_W2 = ${zp.SCRATCH_W2}    ; word")
         asmgen.out(".weak")   // hack to allow user to override the following two with command line redefinition (however, just use '-esa' command line option instead!)
-        asmgen.out("P8ESTACK_LO = ${compTarget.machine.ESTACK_LO.toHex()}")
-        asmgen.out("P8ESTACK_HI = ${compTarget.machine.ESTACK_HI.toHex()}")
         asmgen.out(".endweak")
 
         if(options.symbolDefs.isNotEmpty()) {
@@ -271,9 +269,7 @@ internal class ProgramAndVarsGen(
 
     internal fun translateAsmSubroutine(sub: PtAsmSub) {
         if(sub.inline) {
-            if(options.optimize) {
-                return
-            }
+            return      // subroutine gets inlined at call site.
         }
 
         asmgen.out("")
@@ -373,12 +369,6 @@ internal class ProgramAndVarsGen(
                 else -> throw AssemblyError("weird dt for extravar $dt")
             }
         }
-        if(asmGenInfo.usedRegsaveA)      // will probably never occur
-            asmgen.out("prog8_regsaveA     .byte  ?")
-        if(asmGenInfo.usedRegsaveX)
-            asmgen.out("prog8_regsaveX     .byte  ?")
-        if(asmGenInfo.usedRegsaveY)
-            asmgen.out("prog8_regsaveY     .byte  ?")
         if(asmGenInfo.usedFloatEvalResultVar1)
             asmgen.out("$subroutineFloatEvalResultVar1    .fill  ${options.compTarget.machine.FLOAT_MEM_SIZE}")
         if(asmGenInfo.usedFloatEvalResultVar2)
@@ -438,12 +428,12 @@ internal class ProgramAndVarsGen(
                 asmgen.out("""
                     lda  #<${name}_init_value
                     ldy  #>${name}_init_value
-                    sta  cx16.r0L
-                    sty  cx16.r0H
+                    sta  cx16.r0
+                    sty  cx16.r0+1
                     lda  #<${name}
                     ldy  #>${name}
-                    sta  cx16.r1L
-                    sty  cx16.r1H
+                    sta  cx16.r1
+                    sty  cx16.r1+1
                     lda  #<$size
                     ldy  #>$size
                     jsr  sys.memcopy""")
@@ -462,7 +452,6 @@ internal class ProgramAndVarsGen(
         }
 
         asmgen.out("""+        
-                    ldx  #127       ; init estack ptr (half page)
                     clv
                     clc""")
     }
@@ -508,7 +497,15 @@ internal class ProgramAndVarsGen(
         for ((scopedName, zpvar) in zpVariables) {
             if (scopedName.startsWith("cx16.r"))
                 continue        // The 16 virtual registers of the cx16 are not actual variables in zp, they're memory mapped
-            asmgen.out("${scopedName.substringAfterLast('.')} \t= ${zpvar.address} \t; zp ${zpvar.dt}")
+            val variable = symboltable.flat.getValue(scopedName) as StStaticVariable
+            if(variable.dt in SplitWordArrayTypes) {
+                val lsbAddr = zpvar.address
+                val msbAddr = zpvar.address + (zpvar.size/2).toUInt()
+                asmgen.out("${scopedName.substringAfterLast('.')}_lsb \t= $lsbAddr \t; zp ${zpvar.dt} (lsbs)")
+                asmgen.out("${scopedName.substringAfterLast('.')}_msb \t= $msbAddr \t; zp ${zpvar.dt} (msbs)")
+            } else {
+                asmgen.out("${scopedName.substringAfterLast('.')} \t= ${zpvar.address} \t; zp ${zpvar.dt}")
+            }
         }
     }
 

codeGenCpu6502/src/prog8/codegen/cpu6502/assignment/AnyExprAsmGen.kt

@@ -0,0 +1,281 @@
+package prog8.codegen.cpu6502.assignment
+
+import prog8.code.ast.PtBinaryExpression
+import prog8.code.ast.PtExpression
+import prog8.code.core.*
+import prog8.code.target.C64Target
+import prog8.code.target.Cx16Target
+import prog8.codegen.cpu6502.AsmGen6502Internal
+
+//
+// This contains codegen for stack-based evaluation of binary expressions.
+// It uses the CPU stack so depth is limited.
+// It is called "as a last resort" if the optimized codegen path is unable
+// to come up with a special case of the expression.
+//
+internal class AnyExprAsmGen(
+    private val asmgen: AsmGen6502Internal
+) {
+    fun assignAnyExpressionUsingStack(expr: PtBinaryExpression, assign: AsmAssignment): Boolean {
+        when(expr.type) {
+            in ByteDatatypes -> {
+                if(expr.left.type in ByteDatatypes && expr.right.type in ByteDatatypes)
+                    return assignByteBinExpr(expr, assign)
+                if (expr.left.type in WordDatatypes && expr.right.type in WordDatatypes) {
+                    require(expr.operator in ComparisonOperators)
+                    throw AssemblyError("words operands comparison -> byte, should have been handled by assignOptimizedComparisonWords()")
+                }
+                if (expr.left.type==DataType.FLOAT && expr.right.type==DataType.FLOAT) {
+                    require(expr.operator in ComparisonOperators)
+                    return assignFloatBinExpr(expr, assign)
+                }
+                throw AssemblyError("weird expr operand types: ${expr.left.type} and {${expr.right.type}")
+            }
+            in WordDatatypes -> {
+                require(expr.left.type in WordDatatypes && expr.right.type in WordDatatypes) {
+                    "both operands must be words"
+                }
+                return assignWordBinExpr(expr)
+            }
+            DataType.FLOAT -> {
+                require(expr.left.type==DataType.FLOAT && expr.right.type==DataType.FLOAT) {
+                    "both operands must be floats"
+                }
+                return assignFloatBinExpr(expr, assign)
+            }
+            else -> throw AssemblyError("weird expression type in assignment")
+        }
+    }
+
+    private fun assignWordBinExpr(expr: PtBinaryExpression): Boolean {
+        when(expr.operator) {
+            "+" -> {
+                TODO("word + at ${expr.position}")
+            }
+            "-" -> {
+                TODO("word - at ${expr.position}")
+            }
+            "*" -> {
+                TODO("word * at ${expr.position}")
+            }
+            "/" -> {
+                TODO("word / at ${expr.position}")
+            }
+            "<<" -> {
+                TODO("word << at ${expr.position}")
+            }
+            ">>" -> {
+                TODO("word >> at ${expr.position}")
+            }
+            "%" -> {
+                TODO("word % at ${expr.position}")
+            }
+            "&", "and" -> {
+                TODO("word and at ${expr.position}")
+            }
+            "|", "or" -> {
+                TODO("word or at ${expr.position}")
+            }
+            "^", "xor" -> {
+                TODO("word xor at ${expr.position}")
+            }
+            "==" -> {
+                TODO("word == at ${expr.position}")
+            }
+            "!=" -> {
+                TODO("word != at ${expr.position}")
+            }
+            "<" -> {
+                TODO("word < at ${expr.position}")
+            }
+            "<=" -> {
+                TODO("word <= at ${expr.position}")
+            }
+            ">" -> {
+                TODO("word > at ${expr.position}")
+            }
+            ">=" -> {
+                TODO("word >= at ${expr.position}")
+            }
+            else -> return false
+        }
+    }
+
+    private fun assignByteBinExpr(expr: PtBinaryExpression, assign: AsmAssignment): Boolean {
+        when(expr.operator) {
+            "+" -> {
+                asmgen.assignExpressionToRegister(expr.left, RegisterOrPair.A, false)
+                asmgen.out("  pha")
+                asmgen.assignExpressionToVariable(expr.right, "P8ZP_SCRATCH_B1", DataType.UBYTE)
+                asmgen.out("  pla |  clc |  adc  P8ZP_SCRATCH_B1")
+                asmgen.assignRegister(RegisterOrPair.A, assign.target)
+                return true
+            }
+            "-" -> {
+                asmgen.assignExpressionToRegister(expr.left, RegisterOrPair.A, false)
+                asmgen.out("  pha")
+                asmgen.assignExpressionToVariable(expr.right, "P8ZP_SCRATCH_B1", DataType.UBYTE)
+                asmgen.out("  pla |  sec |  sbc  P8ZP_SCRATCH_B1")
+                asmgen.assignRegister(RegisterOrPair.A, assign.target)
+                return true
+            }
+            "*" -> {
+                TODO("byte * at ${expr.position}")
+            }
+            "/" -> {
+                TODO("byte / at ${expr.position}")
+            }
+            "<<" -> {
+                TODO("byte << at ${expr.position}")
+            }
+            ">>" -> {
+                TODO("byte >> at ${expr.position}")
+            }
+            "%" -> {
+                TODO("byte % at ${expr.position}")
+            }
+            "&", "and" -> {
+                asmgen.assignExpressionToRegister(expr.left, RegisterOrPair.A, false)
+                asmgen.out("  pha")
+                asmgen.assignExpressionToVariable(expr.right, "P8ZP_SCRATCH_B1", DataType.UBYTE)
+                asmgen.out("  pla |  and  P8ZP_SCRATCH_B1")
+                asmgen.assignRegister(RegisterOrPair.A, assign.target)
+                return true
+            }
+            "|", "or" -> {
+                asmgen.assignExpressionToRegister(expr.left, RegisterOrPair.A, false)
+                asmgen.out("  pha")
+                asmgen.assignExpressionToVariable(expr.right, "P8ZP_SCRATCH_B1", DataType.UBYTE)
+                asmgen.out("  pla |  ora  P8ZP_SCRATCH_B1")
+                asmgen.assignRegister(RegisterOrPair.A, assign.target)
+                return true
+            }
+            "^", "xor" -> {
+                asmgen.assignExpressionToRegister(expr.left, RegisterOrPair.A, false)
+                asmgen.out("  pha")
+                asmgen.assignExpressionToVariable(expr.right, "P8ZP_SCRATCH_B1", DataType.UBYTE)
+                asmgen.out("  pla |  eor  P8ZP_SCRATCH_B1")
+                asmgen.assignRegister(RegisterOrPair.A, assign.target)
+                return true
+            }
+            "==" -> {
+                TODO("byte == at ${expr.position}")
+            }
+            "!=" -> {
+                TODO("byte != at ${expr.position}")
+            }
+            "<" -> {
+                TODO("byte < at ${expr.position}")
+            }
+            "<=" -> {
+                TODO("byte <= at ${expr.position}")
+            }
+            ">" -> {
+                TODO("byte > at ${expr.position}")
+            }
+            ">=" -> {
+                TODO("byte >= at ${expr.position}")
+            }
+            else -> return false
+        }
+    }
+
+    private fun assignFloatBinExpr(expr: PtBinaryExpression, assign: AsmAssignment): Boolean {
+        when(expr.operator) {
+            "+" -> {
+                assignFloatOperandsToFACandARG(expr.left, expr.right)
+                asmgen.out("  jsr  floats.FADDT")
+                asmgen.assignRegister(RegisterOrPair.FAC1, assign.target)
+                return true
+            }
+            "-" -> {
+                assignFloatOperandsToFACandARG(expr.right, expr.left)
+                asmgen.out("  jsr  floats.FSUBT")
+                asmgen.assignRegister(RegisterOrPair.FAC1, assign.target)
+                return true
+            }
+            "*" -> {
+                assignFloatOperandsToFACandARG(expr.left, expr.right)
+                asmgen.out("  jsr  floats.FMULTT")
+                asmgen.assignRegister(RegisterOrPair.FAC1, assign.target)
+                return true
+            }
+            "/" -> {
+                assignFloatOperandsToFACandARG(expr.right, expr.left)
+                asmgen.out("  jsr  floats.FDIVT")
+                asmgen.assignRegister(RegisterOrPair.FAC1, assign.target)
+                return true
+            }
+            "==" -> {
+                setupFloatComparisonFAC1vsVarAY(expr)
+                asmgen.out("  jsr  floats.var_fac1_equal_f")
+                asmgen.assignRegister(RegisterOrPair.A, assign.target)
+                return true
+            }
+            "!=" -> {
+                setupFloatComparisonFAC1vsVarAY(expr)
+                asmgen.out("  jsr  floats.var_fac1_notequal_f")
+                asmgen.assignRegister(RegisterOrPair.A, assign.target)
+                return true
+            }
+            "<" -> {
+                setupFloatComparisonFAC1vsVarAY(expr)
+                asmgen.out("  jsr  floats.var_fac1_less_f")
+                asmgen.assignRegister(RegisterOrPair.A, assign.target)
+                return true
+            }
+            ">" -> {
+                setupFloatComparisonFAC1vsVarAY(expr)
+                asmgen.out("  jsr  floats.var_fac1_greater_f")
+                asmgen.assignRegister(RegisterOrPair.A, assign.target)
+                return true
+            }
+            "<=" -> {
+                setupFloatComparisonFAC1vsVarAY(expr)
+                asmgen.out("  jsr  floats.var_fac1_lesseq_f")
+                asmgen.assignRegister(RegisterOrPair.A, assign.target)
+                return true
+            }
+            ">=" -> {
+                setupFloatComparisonFAC1vsVarAY(expr)
+                asmgen.out("  jsr  floats.var_fac1_greatereq_f")
+                asmgen.assignRegister(RegisterOrPair.A, assign.target)
+                return true
+            }
+            else -> TODO("float expression operator ${expr.operator}")
+        }
+    }
+
+    private fun assignFloatOperandsToFACandARG(left: PtExpression, right: PtExpression) {
+        when(asmgen.options.compTarget.name) {
+            C64Target.NAME -> {
+                // c64 has a quirk: always make sure FAC2 is loaded last (done using CONUPK)  otherwise the result will be corrupt on C64
+                // this requires some more forced copying around of float values in certain cases
+                if (right.isSimple()) {
+                    asmgen.assignExpressionToRegister(left, RegisterOrPair.FAC1, true)
+                    asmgen.assignExpressionToRegister(right, RegisterOrPair.FAC2, true)
+                } else {
+                    asmgen.assignExpressionToRegister(right, RegisterOrPair.FAC1, true)
+                    asmgen.pushFAC1()
+                    asmgen.assignExpressionToRegister(left, RegisterOrPair.FAC1, true)
+                    asmgen.popFAC2()
+                }
+            }
+            Cx16Target.NAME -> {
+                asmgen.assignExpressionToRegister(left, RegisterOrPair.FAC1, true)
+                if (!right.isSimple()) asmgen.pushFAC1()
+                asmgen.assignExpressionToRegister(right, RegisterOrPair.FAC2, true)
+                if (!right.isSimple()) asmgen.popFAC1()
+            }
+            else -> TODO("don't know how to evaluate float expression for selected compilation target")
+        }
+    }
+
+    private fun setupFloatComparisonFAC1vsVarAY(expr: PtBinaryExpression) {
+        asmgen.assignExpressionToRegister(expr.left, RegisterOrPair.FAC1, true)
+        if(!expr.right.isSimple()) asmgen.pushFAC1()
+        asmgen.assignExpressionToVariable(expr.right, "floats.floats_temp_var", DataType.FLOAT)
+        if(!expr.right.isSimple()) asmgen.popFAC1()
+        asmgen.out("  lda  #<floats.floats_temp_var |  ldy  #>floats.floats_temp_var")
+    }
+}

codeGenCpu6502/src/prog8/codegen/cpu6502/assignment/AsmAssignment.kt

@@ -10,8 +10,7 @@ internal enum class TargetStorageKind {
     VARIABLE,
     ARRAY,
     MEMORY,
-    REGISTER,
-    STACK
+    REGISTER
 }
 
 internal enum class SourceStorageKind {
@@ -20,7 +19,6 @@ internal enum class SourceStorageKind {
     ARRAY,
     MEMORY,
     REGISTER,
-    STACK,              // value is already present on stack
     EXPRESSION,         // expression in ast-form, still to be evaluated
 }
 
@@ -120,7 +118,7 @@ internal class AsmAssignTarget(val kind: TargetStorageKind,
             TargetStorageKind.MEMORY -> {
                 left isSameAs memory!!
             }
-            TargetStorageKind.REGISTER, TargetStorageKind.STACK -> {
+            TargetStorageKind.REGISTER -> {
                 false
             }
         }

codeGenCpu6502/test/Dummies.kt

@@ -18,6 +18,8 @@ internal object DummyMemsizer : IMemSizer {
 }
 
 internal object DummyStringEncoder : IStringEncoding {
+    override val defaultEncoding: Encoding = Encoding.ISO
+
     override fun encodeString(str: String, encoding: Encoding): List<UByte> {
         return emptyList()
     }

codeGenCpu6502/test/TestCodegen.kt

@@ -22,6 +22,7 @@ class TestCodegen: FunSpec({
             CbmPrgLauncherType.NONE,
             ZeropageType.DONTUSE,
             zpReserved = emptyList(),
+            zpAllowed = CompilationOptions.AllZeropageAllowed,
             floats = true,
             noSysInit = false,
             compTarget = target,
@@ -44,7 +45,7 @@ class TestCodegen: FunSpec({
 //}
         val codegen = AsmGen6502(prefixSymbols = false)
         val program = PtProgram("test", DummyMemsizer, DummyStringEncoder)
-        val block = PtBlock("main", null, false, false, false, PtBlock.BlockAlignment.NONE, SourceCode.Generated("test"), Position.DUMMY)
+        val block = PtBlock("main", null, false, false, false, false, PtBlock.BlockAlignment.NONE, SourceCode.Generated("test"), Position.DUMMY)
         val sub = PtSub("start", emptyList(), null, Position.DUMMY)
         sub.add(PtVariable("pi", DataType.UBYTE, ZeropageWish.DONTCARE, PtNumber(DataType.UBYTE, 0.0, Position.DUMMY), null, Position.DUMMY))
         sub.add(PtVariable("particleX", DataType.ARRAY_UB, ZeropageWish.DONTCARE, null, 3u, Position.DUMMY))
@@ -94,7 +95,7 @@ class TestCodegen: FunSpec({
         program.add(block)
 
         // define the "cx16.r0" virtual register
-        val cx16block = PtBlock("cx16", null, false, false, false, PtBlock.BlockAlignment.NONE, SourceCode.Generated("test"), Position.DUMMY)
+        val cx16block = PtBlock("cx16", null, false, false, false, false, PtBlock.BlockAlignment.NONE, SourceCode.Generated("test"), Position.DUMMY)
         cx16block.add(PtMemMapped("r0", DataType.UWORD, 100u, null, Position.DUMMY))
         program.add(cx16block)
 
@@ -106,7 +107,7 @@ class TestCodegen: FunSpec({
         Files.deleteIfExists(Path("${result.name}.asm"))
     }
 
-    test("64tass assembler available? - if this fails you need to install 64tass in the path") {
+    test("64tass assembler available? - if this fails you need to install 64tass version 1.58 or newer in the path") {
         val command = mutableListOf("64tass", "--version")
         shouldNotThrowAny {
             val proc = ProcessBuilder(command).start()

codeGenExperimental/build.gradle

@@ -36,10 +36,10 @@ dependencies {
 sourceSets {
     main {
         java {
-            srcDirs = ["${project.projectDir}/src"]
+            srcDir "${project.projectDir}/src"
         }
         resources {
-            srcDirs = ["${project.projectDir}/res"]
+            srcDir "${project.projectDir}/res"
         }
     }
 }

codeGenExperimental/src/prog8/codegen/experimental/ExperiCodeGen.kt

@@ -15,7 +15,7 @@ class ExperiCodeGen: ICodeGeneratorBackend {
         symbolTable: SymbolTable,
         options: CompilationOptions,
         errors: IErrorReporter
-    ): IAssemblyProgram? {
+    ): IAssemblyProgram {
 
         // you could write a code generator directly on the PtProgram AST,
         // but you can also use the Intermediate Representation to build a codegen on:

codeGenIntermediate/build.gradle

@@ -30,16 +30,16 @@ dependencies {
     // implementation "org.jetbrains.kotlin:kotlin-reflect"
     implementation "com.michael-bull.kotlin-result:kotlin-result-jvm:1.1.18"
 
-    testImplementation 'io.kotest:kotest-runner-junit5-jvm:5.6.2'
+    testImplementation 'io.kotest:kotest-runner-junit5-jvm:5.8.0'
 }
 
 sourceSets {
     main {
         java {
-            srcDirs = ["${project.projectDir}/src"]
+            srcDir "${project.projectDir}/src"
         }
         resources {
-            srcDirs = ["${project.projectDir}/res"]
+            srcDir "${project.projectDir}/res"
         }
     }
     test {

codeGenIntermediate/src/prog8/codegen/intermediate/AssignmentGen.kt

@@ -13,7 +13,9 @@ internal class AssignmentGen(private val codeGen: IRCodeGen, private val express
         if(assignment.target.children.single() is PtMachineRegister)
             throw AssemblyError("assigning to a register should be done by just evaluating the expression into resultregister")
 
-        return translateRegularAssign(assignment)
+        val chunks = translateRegularAssign(assignment)
+        chunks.filterIsInstance<IRCodeChunk>().firstOrNull()?.appendSrcPosition(assignment.position)
+        return chunks
     }
 
     internal fun translate(augAssign: PtAugmentedAssign): IRCodeChunks {
@@ -24,7 +26,7 @@ internal class AssignmentGen(private val codeGen: IRCodeGen, private val express
         val memory = augAssign.target.memory
         val array = augAssign.target.array
 
-        return if(ident!=null) {
+        val chunks = if(ident!=null) {
             assignVarAugmented(ident.name, augAssign)
         } else if(memory != null) {
             if(memory.address is PtNumber)
@@ -39,6 +41,8 @@ internal class AssignmentGen(private val codeGen: IRCodeGen, private val express
         } else {
             fallbackAssign(augAssign)
         }
+        chunks.filterIsInstance<IRCodeChunk>().firstOrNull()?.appendSrcPosition(augAssign.position)
+        return chunks
     }
 
     private fun assignMemoryAugmented(
@@ -48,15 +52,15 @@ internal class AssignmentGen(private val codeGen: IRCodeGen, private val express
         val value = assignment.value
         val vmDt = irType(value.type)
         return when(assignment.operator) {
-            "+" -> expressionEval.operatorPlusInplace(address, null, vmDt, value)
-            "-" -> expressionEval.operatorMinusInplace(address, null, vmDt, value)
-            "*" -> expressionEval.operatorMultiplyInplace(address, null, vmDt, value)
-            "/" -> expressionEval.operatorDivideInplace(address, null, vmDt, value.type in SignedDatatypes, value)
-            "|" -> expressionEval.operatorOrInplace(address, null, vmDt, value)
-            "&" -> expressionEval.operatorAndInplace(address, null, vmDt, value)
-            "^" -> expressionEval.operatorXorInplace(address, null, vmDt, value)
-            "<<" -> expressionEval.operatorShiftLeftInplace(address, null, vmDt, value)
-            ">>" -> expressionEval.operatorShiftRightInplace(address, null, vmDt, value.type in SignedDatatypes, value)
+            "+=" -> expressionEval.operatorPlusInplace(address, null, vmDt, value)
+            "-=" -> expressionEval.operatorMinusInplace(address, null, vmDt, value)
+            "*=" -> expressionEval.operatorMultiplyInplace(address, null, vmDt, value)
+            "/=" -> expressionEval.operatorDivideInplace(address, null, vmDt, value.type in SignedDatatypes, value)
+            "|=" -> expressionEval.operatorOrInplace(address, null, vmDt, value)
+            "&=" -> expressionEval.operatorAndInplace(address, null, vmDt, value)
+            "^=" -> expressionEval.operatorXorInplace(address, null, vmDt, value)
+            "<<=" -> expressionEval.operatorShiftLeftInplace(address, null, vmDt, value)
+            ">>=" -> expressionEval.operatorShiftRightInplace(address, null, vmDt, value.type in SignedDatatypes, value)
             "%=" -> expressionEval.operatorModuloInplace(address, null, vmDt, value)
             "==" -> expressionEval.operatorEqualsInplace(address, null, vmDt, value)
             "!=" -> expressionEval.operatorNotEqualsInplace(address, null, vmDt, value)
@@ -96,8 +100,6 @@ internal class AssignmentGen(private val codeGen: IRCodeGen, private val express
     }
 
     private fun fallbackAssign(origAssign: PtAugmentedAssign): IRCodeChunks {
-        if (codeGen.options.slowCodegenWarnings)
-            codeGen.errors.warn("indirect code for in-place assignment", origAssign.position)
         val value: PtExpression
         if(origAssign.operator in PrefixOperators) {
             value = PtPrefix(origAssign.operator, origAssign.value.type, origAssign.value.position)
@@ -200,8 +202,7 @@ internal class AssignmentGen(private val codeGen: IRCodeGen, private val express
             val variable = targetArray.variable.name
             val itemsize = codeGen.program.memsizer.memorySize(targetArray.type)
 
-            if(targetArray.variable.type==DataType.UWORD) {
-                // indexing a pointer var instead of a real array or string
+            if(targetArray.usesPointerVariable) {
                 if(itemsize!=1)
                     throw AssemblyError("non-array var indexing requires bytes dt")
                 if(targetArray.index.type!=DataType.UBYTE)

codeGenIntermediate/src/prog8/codegen/intermediate/BuiltinFuncGen.kt

@@ -24,36 +24,56 @@ internal class BuiltinFuncGen(private val codeGen: IRCodeGen, private val exprGe
             "popw" -> funcPopw(call)
             "push" -> funcPush(call)
             "pushw" -> funcPushw(call)
-            "rsave",
-            "rsavex",
-            "rrestore",
-            "rrestorex" -> ExpressionCodeResult.EMPTY  // vm doesn't have registers to save/restore
+            "rsave", "rrestore" -> ExpressionCodeResult.EMPTY  // vm doesn't have registers to save/restore
             "callfar" -> funcCallfar(call)
             "msb" -> funcMsb(call)
             "lsb" -> funcLsb(call)
             "memory" -> funcMemory(call)
-            "peek" -> funcPeek(call)
-            "peekw" -> funcPeekW(call)
-            "poke" -> funcPoke(call)
-            "pokew" -> funcPokeW(call)
-            "pokemon" -> ExpressionCodeResult.EMPTY     // easter egg function
+            "peek" -> funcPeek(call, IRDataType.BYTE)
+            "peekw" -> funcPeek(call, IRDataType.WORD)
+            "peekf" -> funcPeek(call, IRDataType.FLOAT)
+            "poke" -> funcPoke(call, IRDataType.BYTE)
+            "pokew" -> funcPoke(call, IRDataType.WORD)
+            "pokef" -> funcPoke(call, IRDataType.FLOAT)
+            "pokemon" -> funcPokemon(call)
             "mkword" -> funcMkword(call)
             "clamp__byte", "clamp__ubyte", "clamp__word", "clamp__uword" -> funcClamp(call)
             "min__byte", "min__ubyte", "min__word", "min__uword" -> funcMin(call)
             "max__byte", "max__ubyte", "max__word", "max__uword" -> funcMax(call)
             "sort" -> funcSort(call)
             "reverse" -> funcReverse(call)
+            "setlsb" -> funcSetLsbMsb(call, false)
+            "setmsb" -> funcSetLsbMsb(call, true)
             "rol" -> funcRolRor(Opcode.ROXL, call)
             "ror" -> funcRolRor(Opcode.ROXR, call)
             "rol2" -> funcRolRor(Opcode.ROL, call)
             "ror2" -> funcRolRor(Opcode.ROR, call)
             "prog8_lib_stringcompare" -> funcStringCompare(call)
+            "prog8_lib_square_byte" -> funcSquare(call, IRDataType.BYTE)
+            "prog8_lib_square_word" -> funcSquare(call, IRDataType.WORD)
             else -> throw AssemblyError("missing builtinfunc for ${call.name}")
         }
     }
 
+    private fun funcSquare(call: PtBuiltinFunctionCall, resultType: IRDataType): ExpressionCodeResult {
+        val result = mutableListOf<IRCodeChunkBase>()
+        val valueTr = exprGen.translateExpression(call.args[0])
+        addToResult(result, valueTr, valueTr.resultReg, valueTr.resultFpReg)
+        return if(resultType==IRDataType.FLOAT) {
+            val resultFpReg = codeGen.registers.nextFreeFloat()
+            addInstr(result, IRInstruction(Opcode.SQUARE, resultType, fpReg1 = resultFpReg, fpReg2 = valueTr.resultFpReg), null)
+            ExpressionCodeResult(result, resultType, -1, resultFpReg)
+        }
+        else {
+            val resultReg = codeGen.registers.nextFree()
+            addInstr(result, IRInstruction(Opcode.SQUARE, resultType, reg1 = resultReg, reg2 = valueTr.resultReg), null)
+            ExpressionCodeResult(result, resultType, resultReg, -1)
+        }
+    }
+
     private fun funcCallfar(call: PtBuiltinFunctionCall): ExpressionCodeResult {
         val result = mutableListOf<IRCodeChunkBase>()
+        addInstr(result, IRInstruction(Opcode.PREPARECALL, immediate = 3), null)
         val bankTr = exprGen.translateExpression(call.args[0])
         val addressTr = exprGen.translateExpression(call.args[1])
         val argumentwordTr = exprGen.translateExpression(call.args[2])
@@ -95,6 +115,7 @@ internal class BuiltinFuncGen(private val codeGen: IRCodeGen, private val exprGe
 
     private fun funcStringCompare(call: PtBuiltinFunctionCall): ExpressionCodeResult {
         val result = mutableListOf<IRCodeChunkBase>()
+        addInstr(result, IRInstruction(Opcode.PREPARECALL, immediate = 2), null)
         val left  = exprGen.translateExpression(call.args[0])
         val right = exprGen.translateExpression(call.args[1])
         addToResult(result, left, left.resultReg, -1)
@@ -129,6 +150,7 @@ internal class BuiltinFuncGen(private val codeGen: IRCodeGen, private val exprGe
                 else -> throw IllegalArgumentException("weird type")
             }
         val result = mutableListOf<IRCodeChunkBase>()
+        addInstr(result, IRInstruction(Opcode.PREPARECALL, immediate = 2), null)
         val tr = exprGen.translateExpression(call.args[0])
         addToResult(result, tr, tr.resultReg, -1)
         val lengthReg = codeGen.registers.nextFree()
@@ -150,6 +172,7 @@ internal class BuiltinFuncGen(private val codeGen: IRCodeGen, private val exprGe
                 else -> throw IllegalArgumentException("weird type")
             }
         val result = mutableListOf<IRCodeChunkBase>()
+        addInstr(result, IRInstruction(Opcode.PREPARECALL, immediate = 2), null)
         val tr = exprGen.translateExpression(call.args[0])
         addToResult(result, tr, tr.resultReg, -1)
         val lengthReg = codeGen.registers.nextFree()
@@ -293,6 +316,7 @@ internal class BuiltinFuncGen(private val codeGen: IRCodeGen, private val exprGe
                 else -> throw IllegalArgumentException("weird type to reverse")
             }
         val result = mutableListOf<IRCodeChunkBase>()
+        addInstr(result, IRInstruction(Opcode.PREPARECALL, immediate = 2), null)
         val tr = exprGen.translateExpression(call.args[0])
         addToResult(result, tr, tr.resultReg, -1)
         val lengthReg = codeGen.registers.nextFree()
@@ -316,6 +340,7 @@ internal class BuiltinFuncGen(private val codeGen: IRCodeGen, private val exprGe
                 else -> throw IllegalArgumentException("weird type to sort")
             }
         val result = mutableListOf<IRCodeChunkBase>()
+        addInstr(result, IRInstruction(Opcode.PREPARECALL, immediate = 2), null)
         val tr = exprGen.translateExpression(call.args[0])
         addToResult(result, tr, tr.resultReg, -1)
         val lengthReg = codeGen.registers.nextFree()
@@ -326,19 +351,25 @@ internal class BuiltinFuncGen(private val codeGen: IRCodeGen, private val exprGe
 
     private fun funcMkword(call: PtBuiltinFunctionCall): ExpressionCodeResult {
         val result = mutableListOf<IRCodeChunkBase>()
-        val msbTr = exprGen.translateExpression(call.args[0])
-        addToResult(result, msbTr, msbTr.resultReg, -1)
-        val lsbTr = exprGen.translateExpression(call.args[1])
-        addToResult(result, lsbTr, lsbTr.resultReg, -1)
         val resultReg = codeGen.registers.nextFree()
-        result += IRCodeChunk(null, null).also {
-            it += IRInstruction(Opcode.CONCAT, IRDataType.BYTE, reg1=resultReg, reg2 = lsbTr.resultReg, reg3 = msbTr.resultReg)
+        if((call.args[0] as? PtNumber)?.number == 0.0) {
+            // msb is 0, use EXT
+            val lsbTr = exprGen.translateExpression(call.args[1])
+            addToResult(result, lsbTr, lsbTr.resultReg, -1)
+            addInstr(result, IRInstruction(Opcode.EXT, IRDataType.BYTE, reg1=resultReg, reg2 = lsbTr.resultReg), null)
+        } else {
+            val msbTr = exprGen.translateExpression(call.args[0])
+            addToResult(result, msbTr, msbTr.resultReg, -1)
+            val lsbTr = exprGen.translateExpression(call.args[1])
+            addToResult(result, lsbTr, lsbTr.resultReg, -1)
+            addInstr(result, IRInstruction(Opcode.CONCAT, IRDataType.BYTE, reg1=resultReg, reg2 = msbTr.resultReg, reg3 = lsbTr.resultReg), null)
         }
         return ExpressionCodeResult(result, IRDataType.WORD, resultReg, -1)
     }
 
     private fun funcClamp(call: PtBuiltinFunctionCall): ExpressionCodeResult {
         val result = mutableListOf<IRCodeChunkBase>()
+        addInstr(result, IRInstruction(Opcode.PREPARECALL, immediate = 3), null)
         val type = irType(call.type)
         val valueTr = exprGen.translateExpression(call.args[0])
         val minimumTr = exprGen.translateExpression(call.args[1])
@@ -411,118 +442,148 @@ internal class BuiltinFuncGen(private val codeGen: IRCodeGen, private val exprGe
         return ExpressionCodeResult(result, type, leftTr.resultReg, -1)
     }
 
-    private fun funcPokeW(call: PtBuiltinFunctionCall): ExpressionCodeResult {
+    private fun funcPoke(call: PtBuiltinFunctionCall, dt: IRDataType): ExpressionCodeResult {
         val result = mutableListOf<IRCodeChunkBase>()
         if(codeGen.isZero(call.args[1])) {
             if (call.args[0] is PtNumber) {
                 val address = (call.args[0] as PtNumber).number.toInt()
                 result += IRCodeChunk(null, null).also {
-                    it += IRInstruction(Opcode.STOREZM, IRDataType.WORD, address = address)
+                    it += IRInstruction(Opcode.STOREZM, dt, address = address)
                 }
             } else {
                 val tr = exprGen.translateExpression(call.args[0])
                 addToResult(result, tr, tr.resultReg, -1)
                 result += IRCodeChunk(null, null).also {
-                    it += IRInstruction(Opcode.STOREZI, IRDataType.WORD, reg1 = tr.resultReg)
+                    it += IRInstruction(Opcode.STOREZI, dt, reg1 = tr.resultReg)
                 }
             }
         } else {
             if (call.args[0] is PtNumber) {
                 val address = (call.args[0] as PtNumber).number.toInt()
                 val tr = exprGen.translateExpression(call.args[1])
-                addToResult(result, tr, tr.resultReg, -1)
-                result += IRCodeChunk(null, null).also {
-                    it += IRInstruction(Opcode.STOREM, IRDataType.WORD, reg1 = tr.resultReg, address = address)
+                if(dt==IRDataType.FLOAT) {
+                    addToResult(result, tr, -1, tr.resultFpReg)
+                    result += IRCodeChunk(null, null).also {
+                        it += IRInstruction(Opcode.STOREM, dt, fpReg1 = tr.resultFpReg, address = address)
+                    }
+                } else {
+                    addToResult(result, tr, tr.resultReg, -1)
+                    result += IRCodeChunk(null, null).also {
+                        it += IRInstruction(Opcode.STOREM, dt, reg1 = tr.resultReg, address = address)
+                    }
                 }
             } else {
                 val addressTr = exprGen.translateExpression(call.args[0])
                 addToResult(result, addressTr, addressTr.resultReg, -1)
                 val valueTr = exprGen.translateExpression(call.args[1])
-                addToResult(result, valueTr, valueTr.resultReg, -1)
-                result += IRCodeChunk(null, null).also {
-                    it += IRInstruction(Opcode.STOREI, IRDataType.WORD, reg1 = valueTr.resultReg, reg2 = addressTr.resultReg)
+                if(dt==IRDataType.FLOAT) {
+                    addToResult(result, valueTr, -1, valueTr.resultFpReg)
+                    result += IRCodeChunk(null, null).also {
+                        it += IRInstruction(Opcode.STOREI, IRDataType.FLOAT, reg1 = addressTr.resultReg, fpReg1 = valueTr.resultFpReg)
+                    }
+                } else {
+                    addToResult(result, valueTr, valueTr.resultReg, -1)
+                    result += IRCodeChunk(null, null).also {
+                        it += IRInstruction(Opcode.STOREI, dt, reg1 = valueTr.resultReg, reg2 = addressTr.resultReg)
+                    }
                 }
             }
         }
         return ExpressionCodeResult(result, IRDataType.BYTE, -1, -1)
     }
 
-    private fun funcPoke(call: PtBuiltinFunctionCall): ExpressionCodeResult {
+    private fun funcPeek(call: PtBuiltinFunctionCall, dt: IRDataType): ExpressionCodeResult {
         val result = mutableListOf<IRCodeChunkBase>()
-        if(codeGen.isZero(call.args[1])) {
-            if (call.args[0] is PtNumber) {
+        return if(dt==IRDataType.FLOAT) {
+            if(call.args[0] is PtNumber) {
+                val resultFpRegister = codeGen.registers.nextFreeFloat()
                 val address = (call.args[0] as PtNumber).number.toInt()
+                result += IRCodeChunk(null, null).also {
+                    it += IRInstruction(Opcode.LOADM, IRDataType.FLOAT, fpReg1 = resultFpRegister, address = address)
+                }
+                ExpressionCodeResult(result, IRDataType.FLOAT, -1, resultFpRegister)
+            } else {
+                val tr = exprGen.translateExpression(call.args.single())
+                addToResult(result, tr, tr.resultReg, -1)
+                val resultFpReg = codeGen.registers.nextFreeFloat()
+                result += IRCodeChunk(null, null).also {
+                    it += IRInstruction(Opcode.LOADI, IRDataType.FLOAT, reg1 = tr.resultReg, fpReg1 = resultFpReg)
+                }
+                ExpressionCodeResult(result, IRDataType.FLOAT, -1, resultFpReg)
+            }
+        } else {
+            if (call.args[0] is PtNumber) {
+                val resultRegister = codeGen.registers.nextFree()
+                val address = (call.args[0] as PtNumber).number.toInt()
+                result += IRCodeChunk(null, null).also {
+                    it += IRInstruction(Opcode.LOADM, dt, reg1 = resultRegister, address = address)
+                }
+                ExpressionCodeResult(result, dt, resultRegister, -1)
+            } else {
+                val tr = exprGen.translateExpression(call.args.single())
+                addToResult(result, tr, tr.resultReg, -1)
+                val resultReg = codeGen.registers.nextFree()
+                result += IRCodeChunk(null, null).also {
+                    it += IRInstruction(Opcode.LOADI, dt, reg1 = resultReg, reg2 = tr.resultReg)
+                }
+                ExpressionCodeResult(result, dt, resultReg, -1)
+            }
+        }
+    }
+
+    private fun funcPokemon(call: PtBuiltinFunctionCall): ExpressionCodeResult {
+        val result = mutableListOf<IRCodeChunkBase>()
+        val address = call.args[0]
+
+        fun pokeM(result: MutableList<IRCodeChunkBase>, address: Int, value: PtExpression) {
+            if(codeGen.isZero(value)) {
                 result += IRCodeChunk(null, null).also {
                     it += IRInstruction(Opcode.STOREZM, IRDataType.BYTE, address = address)
                 }
             } else {
-                val tr = exprGen.translateExpression(call.args[0])
-                addToResult(result, tr, tr.resultReg, -1)
-                result += IRCodeChunk(null, null).also {
-                    it += IRInstruction(Opcode.STOREZI, IRDataType.BYTE, reg1 = tr.resultReg)
-                }
-            }
-        } else {
-            if (call.args[0] is PtNumber) {
-                val address = (call.args[0] as PtNumber).number.toInt()
-                val tr = exprGen.translateExpression(call.args[1])
+                val tr = exprGen.translateExpression(value)
                 addToResult(result, tr, tr.resultReg, -1)
                 result += IRCodeChunk(null, null).also {
                     it += IRInstruction(Opcode.STOREM, IRDataType.BYTE, reg1 = tr.resultReg, address = address)
                 }
+            }
+        }
+
+        fun pokeI(result: MutableList<IRCodeChunkBase>, register: Int, value: PtExpression) {
+            if(codeGen.isZero(value)) {
+                result += IRCodeChunk(null, null).also {
+                    it += IRInstruction(Opcode.STOREZI, IRDataType.BYTE, reg1 = register)
+                }
             } else {
-                val addressTr = exprGen.translateExpression(call.args[0])
-                addToResult(result, addressTr, addressTr.resultReg, -1)
-                val valueTr = exprGen.translateExpression(call.args[1])
+                val valueTr = exprGen.translateExpression(value)
                 addToResult(result, valueTr, valueTr.resultReg, -1)
                 result += IRCodeChunk(null, null).also {
-                    it += IRInstruction(Opcode.STOREI, IRDataType.BYTE, reg1 = valueTr.resultReg, reg2 = addressTr.resultReg)
+                    it += IRInstruction(Opcode.STOREI, IRDataType.BYTE, reg1 = valueTr.resultReg, reg2 = register)
                 }
             }
         }
-        return ExpressionCodeResult(result, IRDataType.BYTE, -1, -1)
-    }
 
-    private fun funcPeekW(call: PtBuiltinFunctionCall): ExpressionCodeResult {
-        val result = mutableListOf<IRCodeChunkBase>()
-        return if(call.args[0] is PtNumber) {
+        return if(address is PtNumber) {
             val resultRegister = codeGen.registers.nextFree()
-            val address = (call.args[0] as PtNumber).number.toInt()
+            val addressNum = address.number.toInt()
             result += IRCodeChunk(null, null).also {
-                it += IRInstruction(Opcode.LOADM, IRDataType.WORD, reg1 = resultRegister, address = address)
+                it += IRInstruction(Opcode.LOADM, IRDataType.BYTE, reg1 = resultRegister, address = addressNum)
             }
+            pokeM(result, addressNum, call.args[1])
             ExpressionCodeResult(result, IRDataType.BYTE, resultRegister, -1)
         } else {
-            val tr = exprGen.translateExpression(call.args.single())
-            addToResult(result, tr, tr.resultReg, -1)
+            val addressTr = exprGen.translateExpression(address)
+            addToResult(result, addressTr, addressTr.resultReg, -1)
             val resultReg = codeGen.registers.nextFree()
             result += IRCodeChunk(null, null).also {
-                it += IRInstruction(Opcode.LOADI, IRDataType.WORD, reg1 = resultReg, reg2 = tr.resultReg)
-            }
-            ExpressionCodeResult(result, IRDataType.WORD, resultReg, -1)
-        }
-    }
-
-    private fun funcPeek(call: PtBuiltinFunctionCall): ExpressionCodeResult {
-        val result = mutableListOf<IRCodeChunkBase>()
-        return if(call.args[0] is PtNumber) {
-            val resultRegister = codeGen.registers.nextFree()
-            val address = (call.args[0] as PtNumber).number.toInt()
-            result += IRCodeChunk(null, null).also {
-                it += IRInstruction(Opcode.LOADM, IRDataType.BYTE, reg1 = resultRegister, address = address)
-            }
-            ExpressionCodeResult(result, IRDataType.BYTE, resultRegister, -1)
-        } else {
-            val tr = exprGen.translateExpression(call.args.single())
-            addToResult(result, tr, tr.resultReg, -1)
-            val resultReg = codeGen.registers.nextFree()
-            result += IRCodeChunk(null, null).also {
-                it += IRInstruction(Opcode.LOADI, IRDataType.BYTE, reg1 = resultReg, reg2 = tr.resultReg)
+                it += IRInstruction(Opcode.LOADI, IRDataType.BYTE, reg1 = resultReg, reg2 = addressTr.resultReg)
             }
+            pokeI(result, addressTr.resultReg, call.args[1])
             ExpressionCodeResult(result, IRDataType.BYTE, resultReg, -1)
         }
     }
 
+
     private fun funcMemory(call: PtBuiltinFunctionCall): ExpressionCodeResult {
         val name = (call.args[0] as PtString).value
         val code = IRCodeChunk(null, null)
@@ -534,6 +595,7 @@ internal class BuiltinFuncGen(private val codeGen: IRCodeGen, private val exprGe
     private fun funcLsb(call: PtBuiltinFunctionCall): ExpressionCodeResult {
         return exprGen.translateExpression(call.args.single())
         // note: if a word result is needed, the upper byte is cleared by the typecast that follows. No need to do it here.
+        // TODO to be more strict, maybe we *should* introduce a new result register that is of type .b?
     }
 
     private fun funcMsb(call: PtBuiltinFunctionCall): ExpressionCodeResult {
@@ -560,6 +622,122 @@ internal class BuiltinFuncGen(private val codeGen: IRCodeGen, private val exprGe
         return ExpressionCodeResult(result, vmDt, -1, -1)
     }
 
+    private fun funcSetLsbMsb(call: PtBuiltinFunctionCall, msb: Boolean): ExpressionCodeResult {
+        val result = mutableListOf<IRCodeChunkBase>()
+        val target = call.args[0]
+        val isConstZeroValue = call.args[1].asConstInteger()==0
+        when(target) {
+            is PtIdentifier -> {
+                if(isConstZeroValue) {
+                    result += IRCodeChunk(null, null).also {
+                        val pointerReg = codeGen.registers.nextFree()
+                        it += IRInstruction(Opcode.LOAD, IRDataType.WORD, reg1 = pointerReg, labelSymbol = target.name)
+                        if (msb)
+                            it += IRInstruction(Opcode.INC, IRDataType.WORD, reg1 = pointerReg)
+                        it += IRInstruction(Opcode.STOREZI, IRDataType.BYTE, reg1 = pointerReg)
+                    }
+                } else {
+                    val valueTr = exprGen.translateExpression(call.args[1])
+                    addToResult(result, valueTr, valueTr.resultReg, -1)
+                    result += IRCodeChunk(null, null).also {
+                        val pointerReg = codeGen.registers.nextFree()
+                        it += IRInstruction(Opcode.LOAD, IRDataType.WORD, reg1 = pointerReg, labelSymbol = target.name)
+                        if (msb)
+                            it += IRInstruction(Opcode.INC, IRDataType.WORD, reg1 = pointerReg)
+                        it += IRInstruction(Opcode.STOREI, IRDataType.BYTE, reg1 = valueTr.resultReg, reg2 = pointerReg)
+                    }
+                }
+            }
+            is PtArrayIndexer -> {
+                require(!target.usesPointerVariable)
+                if(target.splitWords) {
+                    // lsb/msb in split arrays, element index 'size' is always 1
+                    val constIndex = target.index.asConstInteger()
+                    val varName = target.variable.name + if(msb) "_msb" else "_lsb"
+                    if(isConstZeroValue) {
+                        if(constIndex!=null) {
+                            val offsetReg = codeGen.registers.nextFree()
+                            result += IRCodeChunk(null, null).also {
+                                it += IRInstruction(Opcode.LOAD, IRDataType.BYTE, reg1=offsetReg, immediate = constIndex)
+                                it += IRInstruction(Opcode.STOREZX, IRDataType.BYTE, reg1=offsetReg, labelSymbol = varName)
+                            }
+                        } else {
+                            val indexTr = exprGen.translateExpression(target.index)
+                            addToResult(result, indexTr, indexTr.resultReg, -1)
+                            result += IRCodeChunk(null, null).also {
+                                it += IRInstruction(Opcode.STOREZX, IRDataType.BYTE, reg1=indexTr.resultReg, labelSymbol = varName)
+                            }
+                        }
+                    } else {
+                        val valueTr = exprGen.translateExpression(call.args[1])
+                        addToResult(result, valueTr, valueTr.resultReg, -1)
+                        if(constIndex!=null) {
+                            val offsetReg = codeGen.registers.nextFree()
+                            result += IRCodeChunk(null, null).also {
+                                it += IRInstruction(Opcode.LOAD, IRDataType.BYTE, reg1=offsetReg, immediate = constIndex)
+                                it += IRInstruction(Opcode.STOREX, IRDataType.BYTE, reg1=valueTr.resultReg, reg2=offsetReg, labelSymbol = varName)
+                            }
+                        } else {
+                            val indexTr = exprGen.translateExpression(target.index)
+                            addToResult(result, indexTr, indexTr.resultReg, -1)
+                            result += IRCodeChunk(null, null).also {
+                                it += IRInstruction(Opcode.STOREX, IRDataType.BYTE, reg1=valueTr.resultReg, reg2=indexTr.resultReg, labelSymbol = varName)
+                            }
+                        }
+                    }
+                }
+                else {
+                    val eltSize = codeGen.program.memsizer.memorySize(target.type)
+                    val constIndex = target.index.asConstInteger()
+                    if(isConstZeroValue) {
+                        if(constIndex!=null) {
+                            val offsetReg = codeGen.registers.nextFree()
+                            val offset = eltSize*constIndex + if(msb) 1 else 0
+                            result += IRCodeChunk(null, null).also {
+                                it += IRInstruction(Opcode.LOAD, IRDataType.BYTE, reg1=offsetReg, immediate = offset)
+                                it += IRInstruction(Opcode.STOREZX, IRDataType.BYTE, reg1=offsetReg, labelSymbol = target.variable.name)
+                            }
+                        } else {
+                            val indexTr = exprGen.translateExpression(target.index)
+                            addToResult(result, indexTr, indexTr.resultReg, -1)
+                            result += IRCodeChunk(null, null).also {
+                                if(eltSize>1)
+                                    it += codeGen.multiplyByConst(IRDataType.BYTE, indexTr.resultReg, eltSize)
+                                if(msb)
+                                    it += IRInstruction(Opcode.INC, IRDataType.BYTE, reg1=indexTr.resultReg)
+                                it += IRInstruction(Opcode.STOREZX, IRDataType.BYTE, reg1=indexTr.resultReg, labelSymbol = target.variable.name)
+                            }
+                        }
+                    } else {
+                        val valueTr = exprGen.translateExpression(call.args[1])
+                        addToResult(result, valueTr, valueTr.resultReg, -1)
+                        if(constIndex!=null) {
+                            val offsetReg = codeGen.registers.nextFree()
+                            val offset = eltSize*constIndex + if(msb) 1 else 0
+                            result += IRCodeChunk(null, null).also {
+                                it += IRInstruction(Opcode.LOAD, IRDataType.BYTE, reg1=offsetReg, immediate = offset)
+                                it += IRInstruction(Opcode.STOREX, IRDataType.BYTE, reg1=valueTr.resultReg, reg2=offsetReg, labelSymbol = target.variable.name)
+                            }
+                        } else {
+                            val indexTr = exprGen.translateExpression(target.index)
+                            addToResult(result, indexTr, indexTr.resultReg, -1)
+                            result += IRCodeChunk(null, null).also {
+                                if(eltSize>1)
+                                    it += codeGen.multiplyByConst(IRDataType.BYTE, indexTr.resultReg, eltSize)
+                                if(msb)
+                                    it += IRInstruction(Opcode.INC, IRDataType.BYTE, reg1=indexTr.resultReg)
+                                it += IRInstruction(Opcode.STOREX, IRDataType.BYTE, reg1=valueTr.resultReg, reg2=indexTr.resultReg, labelSymbol = target.variable.name)
+                            }
+                        }
+                    }
+                }
+            }
+            else -> throw AssemblyError("weird target for setlsb/setmsb: $target")
+        }
+        return ExpressionCodeResult(result, IRDataType.WORD, -1, -1)
+    }
+
+
     private fun assignRegisterTo(target: PtExpression, register: Int): IRCodeChunks {
         val assignment = PtAssignment(target.position)
         val assignTarget = PtAssignTarget(target.position)

codeGenIntermediate/src/prog8/codegen/intermediate/ExpressionGen.kt

@@ -3,10 +3,7 @@ package prog8.codegen.intermediate
 import prog8.code.StRomSub
 import prog8.code.StSub
 import prog8.code.ast.*
-import prog8.code.core.AssemblyError
-import prog8.code.core.DataType
-import prog8.code.core.PassByValueDatatypes
-import prog8.code.core.SignedDatatypes
+import prog8.code.core.*
 import prog8.intermediate.*
 
 internal class ExpressionCodeResult(val chunks: IRCodeChunks, val dt: IRDataType, val resultReg: Int, val resultFpReg: Int) {
@@ -20,6 +17,8 @@ internal class ExpressionCodeResult(val chunks: IRCodeChunks, val dt: IRDataType
         if(resultReg!=-1) require(resultFpReg==-1)
         if(resultFpReg!=-1) require(resultReg==-1)
     }
+
+    fun lastInstruction() = chunks.last().instructions.last()
 }
 
 internal class ExpressionGen(private val codeGen: IRCodeGen) {
@@ -34,7 +33,7 @@ internal class ExpressionGen(private val codeGen: IRCodeGen) {
                 val code = IRCodeChunk(null, null)
                 if(vmDt==IRDataType.FLOAT) {
                     val resultFpRegister = codeGen.registers.nextFreeFloat()
-                    code += IRInstruction(Opcode.LOAD, vmDt, fpReg1 = resultFpRegister, immediateFp = expr.number.toFloat())
+                    code += IRInstruction(Opcode.LOAD, vmDt, fpReg1 = resultFpRegister, immediateFp = expr.number)
                     ExpressionCodeResult(code, vmDt,-1, resultFpRegister)
                 }
                 else {
@@ -69,10 +68,28 @@ internal class ExpressionGen(private val codeGen: IRCodeGen) {
                 val vmDt = irType(expr.type)
                 val symbol = expr.identifier.name
                 // note: LOAD <symbol>  gets you the address of the symbol, whereas LOADM <symbol> would get you the value stored at that location
-                val code = IRCodeChunk(null, null)
+                val result = mutableListOf<IRCodeChunkBase>()
                 val resultRegister = codeGen.registers.nextFree()
-                code += IRInstruction(Opcode.LOAD, vmDt, reg1=resultRegister, labelSymbol = symbol)
-                ExpressionCodeResult(code, vmDt, resultRegister, -1)
+                addInstr(result, IRInstruction(Opcode.LOAD, vmDt, reg1 = resultRegister, labelSymbol = symbol), null)
+                if(expr.isFromArrayElement) {
+                    val indexTr = translateExpression(expr.arrayIndexExpr!!)
+                    addToResult(result, indexTr, indexTr.resultReg, -1)
+                    if(expr.identifier.type in SplitWordArrayTypes) {
+                        result += IRCodeChunk(null, null).also {
+                            // multiply indexTr resultreg by the eltSize and add this to the resultRegister.
+                            it += IRInstruction(Opcode.ADDR, IRDataType.BYTE, reg1=resultRegister, reg2=indexTr.resultReg)
+                        }
+                    } else {
+                        val eltSize = codeGen.program.memsizer.memorySize(expr.identifier.type, 1)
+                        result += IRCodeChunk(null, null).also {
+                            // multiply indexTr resultreg by the eltSize and add this to the resultRegister.
+                            if(eltSize>1)
+                                it += IRInstruction(Opcode.MUL, IRDataType.BYTE, reg1=indexTr.resultReg, immediate = eltSize)
+                            it += IRInstruction(Opcode.ADDR, IRDataType.BYTE, reg1=resultRegister, reg2=indexTr.resultReg)
+                        }
+                    }
+                }
+                ExpressionCodeResult(result, vmDt, resultRegister, -1)
             }
             is PtMemoryByte -> {
                 val result = mutableListOf<IRCodeChunkBase>()
@@ -107,6 +124,7 @@ internal class ExpressionGen(private val codeGen: IRCodeGen) {
         val result = mutableListOf<IRCodeChunkBase>()
         when(check.iterable.type) {
             DataType.STR -> {
+                addInstr(result, IRInstruction(Opcode.PREPARECALL, immediate = 2), null)
                 val elementTr = translateExpression(check.element)
                 addToResult(result, elementTr, elementTr.resultReg, -1)
                 val iterableTr = translateExpression(check.iterable)
@@ -115,6 +133,7 @@ internal class ExpressionGen(private val codeGen: IRCodeGen) {
                 return ExpressionCodeResult(result, IRDataType.BYTE, elementTr.resultReg, -1)
             }
             DataType.ARRAY_UB, DataType.ARRAY_B -> {
+                addInstr(result, IRInstruction(Opcode.PREPARECALL, immediate = 3), null)
                 val elementTr = translateExpression(check.element)
                 addToResult(result, elementTr, elementTr.resultReg, -1)
                 val iterableTr = translateExpression(check.iterable)
@@ -126,6 +145,7 @@ internal class ExpressionGen(private val codeGen: IRCodeGen) {
                 return ExpressionCodeResult(result, IRDataType.BYTE, elementTr.resultReg, -1)
             }
             DataType.ARRAY_UW, DataType.ARRAY_W -> {
+                addInstr(result, IRInstruction(Opcode.PREPARECALL, immediate = 3), null)
                 val elementTr = translateExpression(check.element)
                 addToResult(result, elementTr, elementTr.resultReg, -1)
                 val iterableTr = translateExpression(check.iterable)
@@ -147,8 +167,7 @@ internal class ExpressionGen(private val codeGen: IRCodeGen) {
         val result = mutableListOf<IRCodeChunkBase>()
         val arrayVarSymbol = arrayIx.variable.name
 
-        if(arrayIx.variable.type==DataType.UWORD) {
-            // indexing a pointer var instead of a real array or string
+        if(arrayIx.usesPointerVariable) {
             if(eltSize!=1)
                 throw AssemblyError("non-array var indexing requires bytes dt")
             if(arrayIx.index.type!=DataType.UBYTE)
@@ -171,18 +190,18 @@ internal class ExpressionGen(private val codeGen: IRCodeGen) {
                 val memOffset = (arrayIx.index as PtNumber).number.toInt()
                 result += IRCodeChunk(null, null).also {
                     val tmpRegMsb = codeGen.registers.nextFree()
-                    it += IRInstruction(Opcode.LOADM, IRDataType.BYTE, reg1=resultRegister, immediate = arrayLength, labelSymbol= "${arrayVarSymbol}_lsb+$memOffset")
                     it += IRInstruction(Opcode.LOADM, IRDataType.BYTE, reg1=tmpRegMsb, immediate = arrayLength, labelSymbol= "${arrayVarSymbol}_msb+$memOffset")
-                    it += IRInstruction(Opcode.CONCAT, IRDataType.BYTE, reg1=finalResultReg, reg2=resultRegister, reg3=tmpRegMsb)
+                    it += IRInstruction(Opcode.LOADM, IRDataType.BYTE, reg1=resultRegister, immediate = arrayLength, labelSymbol= "${arrayVarSymbol}_lsb+$memOffset")
+                    it += IRInstruction(Opcode.CONCAT, IRDataType.BYTE, reg1=finalResultReg, reg2=tmpRegMsb, reg3=resultRegister)
                 }
             } else {
                 val tr = translateExpression(arrayIx.index)
                 addToResult(result, tr, tr.resultReg, -1)
                 result += IRCodeChunk(null, null).also {
                     val tmpRegMsb = codeGen.registers.nextFree()
-                    it += IRInstruction(Opcode.LOADX, IRDataType.BYTE, reg1=resultRegister, reg2 = tr.resultReg, immediate = arrayLength, labelSymbol= "${arrayVarSymbol}_lsb")
                     it += IRInstruction(Opcode.LOADX, IRDataType.BYTE, reg1=tmpRegMsb, reg2 = tr.resultReg, immediate = arrayLength, labelSymbol= "${arrayVarSymbol}_msb")
-                    it += IRInstruction(Opcode.CONCAT, IRDataType.BYTE, reg1=finalResultReg, reg2=resultRegister, reg3=tmpRegMsb)
+                    it += IRInstruction(Opcode.LOADX, IRDataType.BYTE, reg1=resultRegister, reg2 = tr.resultReg, immediate = arrayLength, labelSymbol= "${arrayVarSymbol}_lsb")
+                    it += IRInstruction(Opcode.CONCAT, IRDataType.BYTE, reg1=finalResultReg, reg2=tmpRegMsb, reg3=resultRegister)
                 }
             }
             return ExpressionCodeResult(result, vmDt, finalResultReg, -1)
@@ -367,6 +386,7 @@ internal class ExpressionGen(private val codeGen: IRCodeGen) {
         when (val callTarget = codeGen.symbolTable.flat.getValue(fcall.name)) {
             is StSub -> {
                 val result = mutableListOf<IRCodeChunkBase>()
+                addInstr(result, IRInstruction(Opcode.PREPARECALL, immediate = callTarget.parameters.size), null)
                 // assign the arguments
                 val argRegisters = mutableListOf<FunctionCallArgs.ArgumentSpec>()
                 for ((arg, parameter) in fcall.args.zip(callTarget.parameters)) {
@@ -387,8 +407,7 @@ internal class ExpressionGen(private val codeGen: IRCodeGen) {
                         FunctionCallArgs.RegSpec(returnIrType, codeGen.registers.nextFree(), null)
                 }
                 // create the call
-                val call = IRInstruction(Opcode.CALL, labelSymbol = fcall.name, fcallArgs = FunctionCallArgs(argRegisters, returnRegSpec))
-                addInstr(result, call, null)
+                addInstr(result, IRInstruction(Opcode.CALL, labelSymbol = fcall.name, fcallArgs = FunctionCallArgs(argRegisters, returnRegSpec)), null)
                 return if(fcall.void)
                     ExpressionCodeResult(result, IRDataType.BYTE, -1, -1)
                 else if(fcall.type==DataType.FLOAT)
@@ -398,6 +417,7 @@ internal class ExpressionGen(private val codeGen: IRCodeGen) {
             }
             is StRomSub -> {
                 val result = mutableListOf<IRCodeChunkBase>()
+                addInstr(result, IRInstruction(Opcode.PREPARECALL, immediate = callTarget.parameters.size), null)
                 // assign the arguments
                 val argRegisters = mutableListOf<FunctionCallArgs.ArgumentSpec>()
                 for ((arg, parameter) in fcall.args.zip(callTarget.parameters)) {
@@ -544,14 +564,16 @@ internal class ExpressionGen(private val codeGen: IRCodeGen) {
             val resultRegister = codeGen.registers.nextFree()
             val valueReg = codeGen.registers.nextFree()
             val label = codeGen.createLabelName()
-            addInstr(result, IRInstruction(Opcode.LOAD, IRDataType.BYTE, reg1=resultRegister, immediate = 1), null)
-            addInstr(result, IRInstruction(Opcode.FCOMP, IRDataType.FLOAT, reg1=valueReg, fpReg1 = leftTr.resultFpReg, fpReg2 = rightTr.resultFpReg), null)
-            if (notEquals) {
-                addInstr(result, IRInstruction(Opcode.BNE, IRDataType.BYTE, reg1=valueReg, immediate = 0, labelSymbol = label), null)
-            } else {
-                addInstr(result, IRInstruction(Opcode.BEQ, IRDataType.BYTE, reg1=valueReg, immediate = 0, labelSymbol = label), null)
+            result += IRCodeChunk(null, null).also {
+                it += IRInstruction(Opcode.LOAD, IRDataType.BYTE, reg1=resultRegister, immediate = 1)
+                it += IRInstruction(Opcode.FCOMP, IRDataType.FLOAT, reg1=valueReg, fpReg1 = leftTr.resultFpReg, fpReg2 = rightTr.resultFpReg)
+                it += IRInstruction(Opcode.CMPI, IRDataType.BYTE, reg1=valueReg, immediate = 0)
+                it += if (notEquals)
+                    IRInstruction(Opcode.BSTNE, labelSymbol = label)
+                else
+                    IRInstruction(Opcode.BSTEQ, labelSymbol = label)
+                it += IRInstruction(Opcode.LOAD, IRDataType.BYTE, reg1=resultRegister, immediate = 0)
             }
-            addInstr(result, IRInstruction(Opcode.LOAD, IRDataType.BYTE, reg1=resultRegister, immediate = 0), null)
             result += IRCodeChunk(label, null)
             return ExpressionCodeResult(result, IRDataType.BYTE, resultRegister, -1)
         } else {
@@ -691,7 +713,7 @@ internal class ExpressionGen(private val codeGen: IRCodeGen) {
             if(constFactorRight!=null && constFactorRight.type!=DataType.FLOAT) {
                 val tr = translateExpression(binExpr.left)
                 addToResult(result, tr, -1, tr.resultFpReg)
-                val factor = constFactorRight.number.toFloat()
+                val factor = constFactorRight.number
                 result += codeGen.divideByConstFloat(tr.resultFpReg, factor)
                 return ExpressionCodeResult(result, vmDt, -1, tr.resultFpReg)
             } else {
@@ -747,13 +769,13 @@ internal class ExpressionGen(private val codeGen: IRCodeGen) {
             return if(constFactorLeft!=null) {
                 val tr = translateExpression(binExpr.right)
                 addToResult(result, tr, -1, tr.resultFpReg)
-                val factor = constFactorLeft.number.toFloat()
+                val factor = constFactorLeft.number
                 result += codeGen.multiplyByConstFloat(tr.resultFpReg, factor)
                 ExpressionCodeResult(result, vmDt, -1, tr.resultFpReg)
             } else if(constFactorRight!=null) {
                 val tr = translateExpression(binExpr.left)
                 addToResult(result, tr, -1, tr.resultFpReg)
-                val factor = constFactorRight.number.toFloat()
+                val factor = constFactorRight.number
                 result += codeGen.multiplyByConstFloat(tr.resultFpReg, factor)
                 ExpressionCodeResult(result, vmDt, -1, tr.resultFpReg)
             } else {
@@ -801,7 +823,7 @@ internal class ExpressionGen(private val codeGen: IRCodeGen) {
                 return if(binExpr.right is PtNumber) {
                     val tr = translateExpression(binExpr.left)
                     addToResult(result, tr, -1, tr.resultFpReg)
-                    addInstr(result, IRInstruction(Opcode.SUB, vmDt, fpReg1 = tr.resultFpReg, immediateFp = (binExpr.right as PtNumber).number.toFloat()), null)
+                    addInstr(result, IRInstruction(Opcode.SUB, vmDt, fpReg1 = tr.resultFpReg, immediateFp = (binExpr.right as PtNumber).number), null)
                     ExpressionCodeResult(result, vmDt, -1, tr.resultFpReg)
                 } else {
                     val leftTr = translateExpression(binExpr.left)
@@ -856,7 +878,7 @@ internal class ExpressionGen(private val codeGen: IRCodeGen) {
                 return if(binExpr.right is PtNumber) {
                     val tr = translateExpression(binExpr.left)
                     addToResult(result, tr, -1, tr.resultFpReg)
-                    addInstr(result, IRInstruction(Opcode.ADD, vmDt, fpReg1 = tr.resultFpReg, immediateFp = (binExpr.right as PtNumber).number.toFloat()), null)
+                    addInstr(result, IRInstruction(Opcode.ADD, vmDt, fpReg1 = tr.resultFpReg, immediateFp = (binExpr.right as PtNumber).number), null)
                     ExpressionCodeResult(result, vmDt, -1, tr.resultFpReg)
                 } else {
                     val leftTr = translateExpression(binExpr.left)
@@ -928,7 +950,7 @@ internal class ExpressionGen(private val codeGen: IRCodeGen) {
         val constFactorRight = operand as? PtNumber
         if(vmDt==IRDataType.FLOAT) {
             if(constFactorRight!=null && constFactorRight.type!=DataType.FLOAT) {
-                val factor = constFactorRight.number.toFloat()
+                val factor = constFactorRight.number
                 result += codeGen.divideByConstFloatInplace(knownAddress, symbol, factor)
             } else {
                 val tr = translateExpression(operand)
@@ -977,7 +999,7 @@ internal class ExpressionGen(private val codeGen: IRCodeGen) {
         val constFactorRight = operand as? PtNumber
         if(vmDt==IRDataType.FLOAT) {
             if(constFactorRight!=null) {
-                val factor = constFactorRight.number.toFloat()
+                val factor = constFactorRight.number
                 result += codeGen.multiplyByConstFloatInplace(knownAddress, symbol, factor)
             } else {
                 val tr = translateExpression(operand)
@@ -1302,7 +1324,7 @@ internal class ExpressionGen(private val codeGen: IRCodeGen) {
                 // in-place modify a memory location
                 result += IRCodeChunk(null, null).also {
                     it += IRInstruction(Opcode.LOADM, IRDataType.FLOAT, fpReg1 = valueReg, address = knownAddress)
-                    it += IRInstruction(Opcode.LOAD, IRDataType.FLOAT, fpReg1 = numberReg, immediateFp = operand.number.toFloat())
+                    it += IRInstruction(Opcode.LOAD, IRDataType.FLOAT, fpReg1 = numberReg, immediateFp = operand.number)
                     it += IRInstruction(Opcode.FCOMP, IRDataType.FLOAT, reg1=cmpReg, fpReg1 = valueReg, fpReg2 = numberReg)
                     it += IRInstruction(Opcode.LOAD, IRDataType.BYTE, reg1=zeroReg, immediate = 0)
                     it += IRInstruction(compareAndSetOpcode, IRDataType.BYTE, reg1=cmpResultReg, reg2=cmpReg, reg3=zeroReg)
@@ -1313,7 +1335,7 @@ internal class ExpressionGen(private val codeGen: IRCodeGen) {
                 // in-place modify a symbol (variable)
                 result += IRCodeChunk(null, null).also {
                     it += IRInstruction(Opcode.LOADM, IRDataType.FLOAT, fpReg1 = valueReg, labelSymbol = symbol)
-                    it += IRInstruction(Opcode.LOAD, IRDataType.FLOAT, fpReg1 = numberReg, immediateFp = operand.number.toFloat())
+                    it += IRInstruction(Opcode.LOAD, IRDataType.FLOAT, fpReg1 = numberReg, immediateFp = operand.number)
                     it += IRInstruction(Opcode.FCOMP, IRDataType.FLOAT, reg1=cmpReg, fpReg1 = valueReg, fpReg2 = numberReg)
                     it += IRInstruction(Opcode.LOAD, IRDataType.BYTE, reg1=zeroReg, immediate = 0)
                     it += IRInstruction(compareAndSetOpcode, IRDataType.BYTE, reg1=cmpResultReg, reg2=cmpReg, reg3=zeroReg)

codeGenIntermediate/src/prog8/codegen/intermediate/IRCodeGen.kt

@@ -29,9 +29,6 @@ class IRCodeGen(
         irSymbolTable = IRSymbolTable(symbolTable)
         val irProg = IRProgram(program.name, irSymbolTable, options, program.encoding)
 
-        if(options.evalStackBaseAddress!=null)
-            throw AssemblyError("IR doesn't use eval-stack")
-
         // collect global variables initializers
         program.allBlocks().forEach {
             val result = mutableListOf<IRCodeChunkBase>()
@@ -286,13 +283,10 @@ class IRCodeGen(
             else -> TODO("missing codegen for $node")
         }
 
-        chunks.forEach { chunk ->
-            require(chunk.isNotEmpty() || chunk.label != null) {
-                "chunk should have instructions and/or a label"
-            }
-        }
+        val nonEmptyChunks = chunks.filter { it.isNotEmpty() || it.label != null }
+        nonEmptyChunks.filterIsInstance<IRCodeChunk>().firstOrNull()?.appendSrcPosition(node.position)
 
-        return chunks
+        return nonEmptyChunks
     }
 
     private fun readBinaryData(node: PtIncludeBinary): Collection<UByte> {
@@ -413,10 +407,23 @@ class IRCodeGen(
                 result += translateNode(choice.statements)
                 addInstr(result, IRInstruction(Opcode.JUMP, labelSymbol = endLabel), null)
             } else {
-                val choiceLabel = createLabelName()
-                choices.add(choiceLabel to choice)
-                choice.values.children.map { it as PtNumber }.sortedBy { it.number }.forEach { value ->
-                    addInstr(result, IRInstruction(Opcode.BEQ, valueDt, reg1=valueTr.resultReg, immediate = value.number.toInt(), labelSymbol = choiceLabel), null)
+                if(choice.statements.children.isEmpty()) {
+                    // no statements for this choice value, jump to the end immediately
+                    choice.values.children.map { it as PtNumber }.sortedBy { it.number }.forEach { value ->
+                        result += IRCodeChunk(null, null).also {
+                            it += IRInstruction(Opcode.CMPI, valueDt, reg1=valueTr.resultReg, immediate = value.number.toInt())
+                            it += IRInstruction(Opcode.BSTEQ, labelSymbol = endLabel)
+                        }
+                    }
+                } else {
+                    val choiceLabel = createLabelName()
+                    choices.add(choiceLabel to choice)
+                    choice.values.children.map { it as PtNumber }.sortedBy { it.number }.forEach { value ->
+                        result += IRCodeChunk(null, null).also {
+                            it += IRInstruction(Opcode.CMPI, valueDt, reg1=valueTr.resultReg, immediate = value.number.toInt())
+                            it += IRInstruction(Opcode.BSTEQ, labelSymbol = choiceLabel)
+                        }
+                    }
                 }
             }
         }
@@ -458,7 +465,7 @@ class IRCodeGen(
                         addInstr(result, IRInstruction(Opcode.LOAD, IRDataType.BYTE, reg1 = indexReg, immediate = 0), null)
                         result += IRCodeChunk(loopLabel, null).also {
                             it += IRInstruction(Opcode.LOADX, IRDataType.BYTE, reg1 = tmpReg, reg2 = indexReg, labelSymbol = iterable.name)
-                            it += IRInstruction(Opcode.BEQ, IRDataType.BYTE, reg1 = tmpReg, immediate = 0, labelSymbol = endLabel)
+                            it += IRInstruction(Opcode.BSTEQ, labelSymbol = endLabel)
                             it += IRInstruction(Opcode.STOREM, IRDataType.BYTE, reg1 = tmpReg, labelSymbol = loopvarSymbol)
                         }
                         result += translateNode(forLoop.statements)
@@ -478,15 +485,19 @@ class IRCodeGen(
                             val tmpRegLsb = registers.nextFree()
                             val tmpRegMsb = registers.nextFree()
                             val concatReg = registers.nextFree()
-                            it += IRInstruction(Opcode.LOADX, IRDataType.BYTE, reg1=tmpRegLsb, reg2=indexReg, immediate = iterableLength, labelSymbol=iterable.name+"_lsb")
                             it += IRInstruction(Opcode.LOADX, IRDataType.BYTE, reg1=tmpRegMsb, reg2=indexReg, immediate = iterableLength, labelSymbol=iterable.name+"_msb")
-                            it += IRInstruction(Opcode.CONCAT, IRDataType.BYTE, reg1=concatReg, reg2=tmpRegLsb, reg3=tmpRegMsb)
+                            it += IRInstruction(Opcode.LOADX, IRDataType.BYTE, reg1=tmpRegLsb, reg2=indexReg, immediate = iterableLength, labelSymbol=iterable.name+"_lsb")
+                            it += IRInstruction(Opcode.CONCAT, IRDataType.BYTE, reg1=concatReg, reg2=tmpRegMsb, reg3=tmpRegLsb)
                             it += IRInstruction(Opcode.STOREM, irType(elementDt), reg1=concatReg, labelSymbol = loopvarSymbol)
                         }
                         result += translateNode(forLoop.statements)
                         result += IRCodeChunk(null, null).also {
                             it += IRInstruction(Opcode.INC, IRDataType.BYTE, reg1=indexReg)
-                            it += IRInstruction(Opcode.BNE, IRDataType.BYTE, reg1=indexReg, immediate = if(iterableLength==256) 0 else iterableLength, labelSymbol = loopLabel)
+                            if(iterableLength!=256) {
+                                // for length 256, the compare is actually against 0, which doesn't require a separate CMP instruction
+                                it += IRInstruction(Opcode.CMPI, IRDataType.BYTE, reg1=indexReg, immediate = iterableLength)
+                            }
+                            it += IRInstruction(Opcode.BSTNE, labelSymbol = loopLabel)
                         }
                     }
                     else -> {
@@ -501,7 +512,13 @@ class IRCodeGen(
                         }
                         result += translateNode(forLoop.statements)
                         result += addConstReg(IRDataType.BYTE, indexReg, elementSize)
-                        addInstr(result, IRInstruction(Opcode.BNE, IRDataType.BYTE, reg1=indexReg, immediate = if(lengthBytes==256) 0 else lengthBytes, labelSymbol = loopLabel), null)
+                        result += IRCodeChunk(null, null).also {
+                            if(lengthBytes!=256) {
+                                // for length 256, the compare is actually against 0, which doesn't require a separate CMP instruction
+                                it += IRInstruction(Opcode.CMPI, IRDataType.BYTE, reg1=indexReg, immediate = lengthBytes)
+                            }
+                            it += IRInstruction(Opcode.BSTNE, labelSymbol = loopLabel)
+                        }
                     }
                 }
             }
@@ -549,8 +566,11 @@ class IRCodeGen(
         result += labelFirstChunk(translateNode(forLoop.statements), loopLabel)
         if(step==1 || step==-1) {
             // if endvalue == loopvar, stop loop, else iterate
-            addInstr(result, IRInstruction(Opcode.LOADM, loopvarDtIr, reg1 = fromTr.resultReg, labelSymbol = loopvarSymbol), null)
-            addInstr(result, IRInstruction(Opcode.BEQR, loopvarDtIr, reg1=toTr.resultReg, reg2=fromTr.resultReg, labelSymbol = labelAfterFor), null)
+            result += IRCodeChunk(null, null).also {
+                it += IRInstruction(Opcode.LOADM, loopvarDtIr, reg1 = fromTr.resultReg, labelSymbol = loopvarSymbol)
+                it += IRInstruction(Opcode.CMP, loopvarDtIr, reg1=toTr.resultReg, reg2=fromTr.resultReg)
+                it += IRInstruction(Opcode.BSTEQ, labelSymbol = labelAfterFor)
+            }
             result += addConstMem(loopvarDtIr, null, loopvarSymbol, step)
             addInstr(result, IRInstruction(Opcode.JUMP, labelSymbol = loopLabel), null)
         } else {
@@ -580,25 +600,23 @@ class IRCodeGen(
             else -> throw AssemblyError("invalid loopvar node type")
         }
         val loopvarDtIr = irType(loopvarDt)
-        val iterable = forLoop.iterable as PtRange
-        val step = iterable.step.number.toInt()
-        val rangeStart = (iterable.from as PtNumber).number.toInt()
-        val rangeEndUntyped = (iterable.to as PtNumber).number.toInt() + step
-        if(step==0)
-            throw AssemblyError("step 0")
-        if(step>0 && rangeEndUntyped<rangeStart || step<0 && rangeEndUntyped>rangeStart)
+        val iterable = (forLoop.iterable as PtRange).toConstantIntegerRange()!!
+        if(iterable.isEmpty())
             throw AssemblyError("empty range")
-        val rangeEndWrapped = if(loopvarDtIr==IRDataType.BYTE) rangeEndUntyped and 255 else rangeEndUntyped and 65535
+        if(iterable.step==0)
+            throw AssemblyError("step 0")
+        val rangeEndExclusiveUntyped = iterable.last + iterable.step
+        val rangeEndExclusiveWrapped = if(loopvarDtIr==IRDataType.BYTE) rangeEndExclusiveUntyped and 255 else rangeEndExclusiveUntyped and 65535
         val result = mutableListOf<IRCodeChunkBase>()
         val chunk = IRCodeChunk(null, null)
-        chunk += IRInstruction(Opcode.LOAD, loopvarDtIr, reg1=indexReg, immediate = rangeStart)
+        chunk += IRInstruction(Opcode.LOAD, loopvarDtIr, reg1=indexReg, immediate = iterable.first)
         chunk += IRInstruction(Opcode.STOREM, loopvarDtIr, reg1=indexReg, labelSymbol=loopvarSymbol)
         result += chunk
         result += labelFirstChunk(translateNode(forLoop.statements), loopLabel)
-        result += addConstMem(loopvarDtIr, null, loopvarSymbol, step)
-        val chunk2 = IRCodeChunk(null, null)
+        val chunk2 = addConstMem(loopvarDtIr, null, loopvarSymbol, iterable.step)
         chunk2 += IRInstruction(Opcode.LOADM, loopvarDtIr, reg1 = indexReg, labelSymbol = loopvarSymbol)
-        chunk2 += IRInstruction(Opcode.BNE, loopvarDtIr, reg1 = indexReg, immediate = rangeEndWrapped, labelSymbol = loopLabel)
+        chunk2 += IRInstruction(Opcode.CMPI, loopvarDtIr, reg1 = indexReg, immediate = rangeEndExclusiveWrapped)
+        chunk2 += IRInstruction(Opcode.BSTNE, labelSymbol = loopLabel)
         result += chunk2
         return result
     }
@@ -687,23 +705,23 @@ class IRCodeGen(
         return code
     }
 
-    internal fun multiplyByConstFloat(fpReg: Int, factor: Float): IRCodeChunk {
+    internal fun multiplyByConstFloat(fpReg: Int, factor: Double): IRCodeChunk {
         val code = IRCodeChunk(null, null)
-        if(factor==1f)
+        if(factor==1.0)
             return code
-        code += if(factor==0f) {
-            IRInstruction(Opcode.LOAD, IRDataType.FLOAT, fpReg1 = fpReg, immediateFp = 0f)
+        code += if(factor==0.0) {
+            IRInstruction(Opcode.LOAD, IRDataType.FLOAT, fpReg1 = fpReg, immediateFp = 0.0)
         } else {
             IRInstruction(Opcode.MUL, IRDataType.FLOAT, fpReg1 = fpReg, immediateFp = factor)
         }
         return code
     }
 
-    internal fun multiplyByConstFloatInplace(knownAddress: Int?, symbol: String?, factor: Float): IRCodeChunk {
+    internal fun multiplyByConstFloatInplace(knownAddress: Int?, symbol: String?, factor: Double): IRCodeChunk {
         val code = IRCodeChunk(null, null)
-        if(factor==1f)
+        if(factor==1.0)
             return code
-        if(factor==0f) {
+        if(factor==0.0) {
             code += if(knownAddress!=null)
                 IRInstruction(Opcode.STOREZM, IRDataType.FLOAT, address = knownAddress)
             else
@@ -784,25 +802,25 @@ class IRCodeGen(
         return code
     }
 
-    internal fun divideByConstFloat(fpReg: Int, factor: Float): IRCodeChunk {
+    internal fun divideByConstFloat(fpReg: Int, factor: Double): IRCodeChunk {
         val code = IRCodeChunk(null, null)
-        if(factor==1f)
+        if(factor==1.0)
             return code
-        code += if(factor==0f) {
-            IRInstruction(Opcode.LOAD, IRDataType.FLOAT, fpReg1 = fpReg, immediateFp = Float.MAX_VALUE)
+        code += if(factor==0.0) {
+            IRInstruction(Opcode.LOAD, IRDataType.FLOAT, fpReg1 = fpReg, immediateFp = Double.MAX_VALUE)
         } else {
             IRInstruction(Opcode.DIVS, IRDataType.FLOAT, fpReg1 = fpReg, immediateFp = factor)
         }
         return code
     }
 
-    internal fun divideByConstFloatInplace(knownAddress: Int?, symbol: String?, factor: Float): IRCodeChunk {
+    internal fun divideByConstFloatInplace(knownAddress: Int?, symbol: String?, factor: Double): IRCodeChunk {
         val code = IRCodeChunk(null, null)
-        if(factor==1f)
+        if(factor==1.0)
             return code
-        if(factor==0f) {
+        if(factor==0.0) {
             val maxvalueReg = registers.nextFreeFloat()
-            code += IRInstruction(Opcode.LOAD, IRDataType.FLOAT, fpReg1 = maxvalueReg, immediateFp = Float.MAX_VALUE)
+            code += IRInstruction(Opcode.LOAD, IRDataType.FLOAT, fpReg1 = maxvalueReg, immediateFp = Double.MAX_VALUE)
             code += if(knownAddress!=null)
                 IRInstruction(Opcode.STOREM, IRDataType.FLOAT, fpReg1 = maxvalueReg, address = knownAddress)
             else
@@ -957,21 +975,31 @@ class IRCodeGen(
                         fpReg1 = leftTr.resultFpReg,
                         fpReg2 = rightTr.resultFpReg
                     )
-                    val gotoOpcode = when (condition.operator) {
-                        "==" -> Opcode.BEQ
-                        "!=" -> Opcode.BNE
-                        "<" -> Opcode.BLTS
-                        ">" -> Opcode.BGTS
-                        "<=" -> Opcode.BLES
-                        ">=" -> Opcode.BGES
-                        else -> throw AssemblyError("weird operator")
+                    when(condition.operator) {
+                        "==" -> {
+                            it += IRInstruction(Opcode.CMPI, IRDataType.BYTE, reg1 = compResultReg, immediate = 0)
+                            it += branchInstr(goto, Opcode.BSTEQ)
+                        }
+                        "!=" -> {
+                            it += IRInstruction(Opcode.CMPI, IRDataType.BYTE, reg1 = compResultReg, immediate = 0)
+                            it += branchInstr(goto, Opcode.BSTNE)
+                        }
+                        else -> {
+                            val gotoOpcode = when (condition.operator) {
+                                "<" -> Opcode.BLTS
+                                ">" -> Opcode.BGTS
+                                "<=" -> Opcode.BLES
+                                ">=" -> Opcode.BGES
+                                else -> throw AssemblyError("weird operator")
+                            }
+                            it += if (goto.address != null)
+                                IRInstruction(gotoOpcode, IRDataType.BYTE, reg1 = compResultReg, immediate = 0, address = goto.address?.toInt())
+                            else if (goto.generatedLabel != null)
+                                IRInstruction(gotoOpcode, IRDataType.BYTE, reg1 = compResultReg, immediate = 0, labelSymbol = goto.generatedLabel)
+                            else
+                                IRInstruction(gotoOpcode, IRDataType.BYTE, reg1 = compResultReg, immediate = 0, labelSymbol = goto.identifier!!.name)
+                        }
                     }
-                    it += if (goto.address != null)
-                        IRInstruction(gotoOpcode, IRDataType.BYTE, reg1 = compResultReg, immediate = 0, address = goto.address?.toInt())
-                    else if (goto.generatedLabel != null)
-                        IRInstruction(gotoOpcode, IRDataType.BYTE, reg1 = compResultReg, immediate = 0, labelSymbol = goto.generatedLabel)
-                    else
-                        IRInstruction(gotoOpcode, IRDataType.BYTE, reg1 = compResultReg, immediate = 0, labelSymbol = goto.identifier!!.name)
                 }
                 return result
             } else {
@@ -986,6 +1014,13 @@ class IRCodeGen(
         }
     }
 
+    private fun branchInstr(goto: PtJump, branchOpcode: Opcode) = if (goto.address != null)
+        IRInstruction(branchOpcode, address = goto.address?.toInt())
+    else if (goto.generatedLabel != null)
+        IRInstruction(branchOpcode, labelSymbol = goto.generatedLabel)
+    else
+        IRInstruction(branchOpcode, labelSymbol = goto.identifier!!.name)
+
     private fun ifZeroIntThenJump(
         result: MutableList<IRCodeChunkBase>,
         ifElse: PtIfElse,
@@ -996,21 +1031,34 @@ class IRCodeGen(
         val condition = ifElse.condition as PtBinaryExpression
         val leftTr = expressionEval.translateExpression(condition.left)
         addToResult(result, leftTr, leftTr.resultReg, -1)
-        val opcode = when (condition.operator) {
-            "==" -> Opcode.BEQ
-            "!=" -> Opcode.BNE
-            "<" -> if (signed) Opcode.BLTS else Opcode.BLT
-            ">" -> if (signed) Opcode.BGTS else Opcode.BGT
-            "<=" -> if (signed) Opcode.BLES else Opcode.BLE
-            ">=" -> if (signed) Opcode.BGES else Opcode.BGE
-            else -> throw AssemblyError("invalid comparison operator")
+        val requireCompareZero = leftTr.lastInstruction().opcode !in OpcodesThatSetStatusbits
+        when(condition.operator) {
+            "==" -> {
+                if(requireCompareZero)
+                    addInstr(result, IRInstruction(Opcode.CMPI, irDtLeft, reg1 = leftTr.resultReg, immediate = 0), null)
+                addInstr(result, branchInstr(goto, Opcode.BSTEQ), null)
+            }
+            "!=" -> {
+                if(requireCompareZero)
+                    addInstr(result, IRInstruction(Opcode.CMPI, irDtLeft, reg1 = leftTr.resultReg, immediate = 0), null)
+                addInstr(result, branchInstr(goto, Opcode.BSTNE), null)
+            }
+            else -> {
+                val opcode = when (condition.operator) {
+                    "<" -> if (signed) Opcode.BLTS else Opcode.BLT
+                    ">" -> if (signed) Opcode.BGTS else Opcode.BGT
+                    "<=" -> if (signed) Opcode.BLES else Opcode.BLE
+                    ">=" -> if (signed) Opcode.BGES else Opcode.BGE
+                    else -> throw AssemblyError("invalid comparison operator")
+                }
+                if (goto.address != null)
+                    addInstr(result, IRInstruction(opcode, irDtLeft, reg1 = leftTr.resultReg, immediate = 0, address = goto.address?.toInt()), null)
+                else if (goto.generatedLabel != null)
+                    addInstr(result, IRInstruction(opcode, irDtLeft, reg1 = leftTr.resultReg, immediate = 0, labelSymbol = goto.generatedLabel), null)
+                else
+                    addInstr(result, IRInstruction(opcode, irDtLeft, reg1 = leftTr.resultReg, immediate = 0, labelSymbol = goto.identifier!!.name), null)
+            }
         }
-        if (goto.address != null)
-            addInstr(result, IRInstruction(opcode, irDtLeft, reg1 = leftTr.resultReg, immediate = 0, address = goto.address?.toInt()), null)
-        else if (goto.generatedLabel != null)
-            addInstr(result, IRInstruction(opcode, irDtLeft, reg1 = leftTr.resultReg, immediate = 0, labelSymbol = goto.generatedLabel), null)
-        else
-            addInstr(result, IRInstruction(opcode, irDtLeft, reg1 = leftTr.resultReg, immediate = 0, labelSymbol = goto.identifier!!.name), null)
     }
 
     private fun ifNonZeroIntThenJump(
@@ -1022,49 +1070,61 @@ class IRCodeGen(
     ) {
         val condition = ifElse.condition as? PtBinaryExpression
         if(condition==null) {
-            val tr = expressionEval.translateExpression(ifElse.condition)
-            result += tr.chunks
-            if (goto.address != null)
-                addInstr(result, IRInstruction(Opcode.BNE, irDtLeft, reg1 = tr.resultReg, immediate = 0, address = goto.address?.toInt()), null)
-            else if (goto.generatedLabel != null)
-                addInstr(result, IRInstruction(Opcode.BNE, irDtLeft, reg1 = tr.resultReg, immediate = 0, labelSymbol = goto.generatedLabel), null)
-            else
-                addInstr(result, IRInstruction(Opcode.BNE, irDtLeft, reg1 = tr.resultReg, immediate = 0, labelSymbol = goto.identifier!!.name), null)
+            throw AssemblyError("expected condition")
+//            val tr = expressionEval.translateExpression(ifElse.condition)
+//            result += tr.chunks
+//            result += IRCodeChunk(null, null).also {
+//                it += IRInstruction(Opcode.CMPI, irDtLeft, reg1 = tr.resultReg, immediate = 0)      // was redundant CMP most likely
+//                it += branchInstr(goto, Opcode.BSTNE)
+//            }
         } else {
             val leftTr = expressionEval.translateExpression(condition.left)
             addToResult(result, leftTr, leftTr.resultReg, -1)
-            val opcode: Opcode
             val number = (condition.right as? PtNumber)?.number?.toInt()
             if(number!=null) {
                 val firstReg = leftTr.resultReg
-                opcode = when (condition.operator) {
-                    "==" -> Opcode.BEQ
-                    "!=" -> Opcode.BNE
-                    "<" -> if(signed) Opcode.BLTS else Opcode.BLT
-                    ">" -> if(signed) Opcode.BGTS else Opcode.BGT
-                    "<=" -> if(signed) Opcode.BLES else Opcode.BLE
-                    ">=" -> if(signed) Opcode.BGES else Opcode.BGE
-                    else -> throw AssemblyError("invalid comparison operator")
+                when(condition.operator) {
+                    "==" -> {
+                        addInstr(result, IRInstruction(Opcode.CMPI, irDtLeft, reg1 = firstReg, immediate = number), null)
+                        addInstr(result, branchInstr(goto, Opcode.BSTEQ), null)
+                    }
+                    "!=" -> {
+                        addInstr(result, IRInstruction(Opcode.CMPI, irDtLeft, reg1 = firstReg, immediate = number), null)
+                        addInstr(result, branchInstr(goto, Opcode.BSTNE), null)
+                    }
+                    else -> {
+                        val opcode = when (condition.operator) {
+                            "<" -> if(signed) Opcode.BLTS else Opcode.BLT
+                            ">" -> if(signed) Opcode.BGTS else Opcode.BGT
+                            "<=" -> if(signed) Opcode.BLES else Opcode.BLE
+                            ">=" -> if(signed) Opcode.BGES else Opcode.BGE
+                            else -> throw AssemblyError("invalid comparison operator")
+                        }
+                        if (goto.address != null)
+                            addInstr(result, IRInstruction(opcode, irDtLeft, reg1 = firstReg, immediate = number, address = goto.address?.toInt()), null)
+                        else if (goto.generatedLabel != null)
+                            addInstr(result, IRInstruction(opcode, irDtLeft, reg1 = firstReg, immediate = number, labelSymbol = goto.generatedLabel), null)
+                        else
+                            addInstr(result, IRInstruction(opcode, irDtLeft, reg1 = firstReg, immediate = number, labelSymbol = goto.identifier!!.name), null)
+                    }
                 }
-                if (goto.address != null)
-                    addInstr(result, IRInstruction(opcode, irDtLeft, reg1 = firstReg, immediate = number, address = goto.address?.toInt()), null)
-                else if (goto.generatedLabel != null)
-                    addInstr(result, IRInstruction(opcode, irDtLeft, reg1 = firstReg, immediate = number, labelSymbol = goto.generatedLabel), null)
-                else
-                    addInstr(result, IRInstruction(opcode, irDtLeft, reg1 = firstReg, immediate = number, labelSymbol = goto.identifier!!.name), null)
             } else {
                 val rightTr = expressionEval.translateExpression(condition.right)
                 addToResult(result, rightTr, rightTr.resultReg, -1)
                 val firstReg: Int
                 val secondReg: Int
+                val opcode: Opcode
+                var useCmp = false
                 when (condition.operator) {
                     "==" -> {
-                        opcode = Opcode.BEQR
+                        useCmp = true
+                        opcode = Opcode.BSTEQ
                         firstReg = leftTr.resultReg
                         secondReg = rightTr.resultReg
                     }
                     "!=" -> {
-                        opcode = Opcode.BNER
+                        useCmp = true
+                        opcode = Opcode.BSTNE
                         firstReg = leftTr.resultReg
                         secondReg = rightTr.resultReg
                     }
@@ -1092,12 +1152,20 @@ class IRCodeGen(
                     }
                     else -> throw AssemblyError("invalid comparison operator")
                 }
-                if (goto.address != null)
-                    addInstr(result, IRInstruction(opcode, irDtLeft, reg1 = firstReg, reg2 = secondReg, address = goto.address?.toInt()), null)
-                else if (goto.generatedLabel != null)
-                    addInstr(result, IRInstruction(opcode, irDtLeft, reg1 = firstReg, reg2 = secondReg, labelSymbol = goto.generatedLabel), null)
-                else
-                    addInstr(result, IRInstruction(opcode, irDtLeft, reg1 = firstReg, reg2 = secondReg, labelSymbol = goto.identifier!!.name), null)
+
+                if(useCmp) {
+                    result += IRCodeChunk(null, null).also {
+                        it += IRInstruction(Opcode.CMP, irDtLeft, reg1 = firstReg, reg2 = secondReg)
+                        it += branchInstr(goto, opcode)
+                    }
+                } else {
+                    if (goto.address != null)
+                        addInstr(result, IRInstruction(opcode, irDtLeft, reg1 = firstReg, reg2 = secondReg, address = goto.address?.toInt()), null)
+                    else if (goto.generatedLabel != null)
+                        addInstr(result, IRInstruction(opcode, irDtLeft, reg1 = firstReg, reg2 = secondReg, labelSymbol = goto.generatedLabel), null)
+                    else
+                        addInstr(result, IRInstruction(opcode, irDtLeft, reg1 = firstReg, reg2 = secondReg, labelSymbol = goto.identifier!!.name), null)
+                }
             }
         }
     }
@@ -1105,6 +1173,7 @@ class IRCodeGen(
     private fun translateIfElseZeroComparison(ifElse: PtIfElse, irDtLeft: IRDataType, signed: Boolean): IRCodeChunks {
         val result = mutableListOf<IRCodeChunkBase>()
         val elseBranch: Opcode
+        var useCmpi = false     // for the branch opcodes that have been converted to CMPI + BSTxx form already
         val compResultReg: Int
         val branchDt: IRDataType
         val condition = ifElse.condition as PtBinaryExpression
@@ -1115,16 +1184,22 @@ class IRCodeGen(
             addToResult(result, leftTr, -1, leftTr.resultFpReg)
             result += IRCodeChunk(null, null).also {
                 val rightFpReg = registers.nextFreeFloat()
-                it += IRInstruction(Opcode.LOAD, IRDataType.FLOAT, fpReg1 = rightFpReg, immediateFp = 0f)
+                it += IRInstruction(Opcode.LOAD, IRDataType.FLOAT, fpReg1 = rightFpReg, immediateFp = 0.0)
                 it += IRInstruction(Opcode.FCOMP, IRDataType.FLOAT, reg1=compResultReg, fpReg1 = leftTr.resultFpReg, fpReg2 = rightFpReg)
             }
-            elseBranch = when (condition.operator) {
-                "==" -> Opcode.BNE
-                "!=" -> Opcode.BEQ
-                "<" -> Opcode.BGES
-                ">" -> Opcode.BLES
-                "<=" -> Opcode.BGTS
-                ">=" -> Opcode.BLTS
+            when (condition.operator) {
+                "==" -> {
+                    elseBranch = Opcode.BSTNE
+                    useCmpi = true
+                }
+                "!=" -> {
+                    elseBranch = Opcode.BSTEQ
+                    useCmpi = true
+                }
+                "<" -> elseBranch = Opcode.BGES
+                ">" -> elseBranch = Opcode.BLES
+                "<=" -> elseBranch = Opcode.BGTS
+                ">=" -> elseBranch = Opcode.BLTS
                 else -> throw AssemblyError("weird operator")
             }
         } else {
@@ -1133,13 +1208,19 @@ class IRCodeGen(
             val tr = expressionEval.translateExpression(condition.left)
             compResultReg = tr.resultReg
             addToResult(result, tr, tr.resultReg, -1)
-            elseBranch = when (condition.operator) {
-                "==" -> Opcode.BNE
-                "!=" -> Opcode.BEQ
-                "<" -> if (signed) Opcode.BGES else Opcode.BGE
-                ">" -> if (signed) Opcode.BLES else Opcode.BLE
-                "<=" -> if (signed) Opcode.BGTS else Opcode.BGT
-                ">=" -> if (signed) Opcode.BLTS else Opcode.BLT
+            when (condition.operator) {
+                "==" -> {
+                    elseBranch = Opcode.BSTNE
+                    useCmpi = true
+                }
+                "!=" -> {
+                    elseBranch = Opcode.BSTEQ
+                    useCmpi = true
+                }
+                "<" -> elseBranch = if (signed) Opcode.BGES else Opcode.BGE
+                ">" -> elseBranch = if (signed) Opcode.BLES else Opcode.BLE
+                "<=" -> elseBranch = if (signed) Opcode.BGTS else Opcode.BGT
+                ">=" -> elseBranch = if (signed) Opcode.BLTS else Opcode.BLT
                 else -> throw AssemblyError("weird operator")
             }
         }
@@ -1147,14 +1228,26 @@ class IRCodeGen(
         if(ifElse.elseScope.children.isEmpty()) {
             // just if
             val afterIfLabel = createLabelName()
-            addInstr(result, IRInstruction(elseBranch, branchDt, reg1=compResultReg, immediate = 0, labelSymbol = afterIfLabel), null)
+            if(useCmpi) {
+                result += IRCodeChunk(null, null).also {
+                    it += IRInstruction(Opcode.CMPI, branchDt, reg1=compResultReg, immediate = 0)
+                    it += IRInstruction(elseBranch, labelSymbol = afterIfLabel)
+                }
+            } else
+                addInstr(result, IRInstruction(elseBranch, branchDt, reg1=compResultReg, immediate = 0, labelSymbol = afterIfLabel), null)
             result += translateNode(ifElse.ifScope)
             result += IRCodeChunk(afterIfLabel, null)
         } else {
             // if and else
             val elseLabel = createLabelName()
             val afterIfLabel = createLabelName()
-            addInstr(result, IRInstruction(elseBranch, branchDt, reg1=compResultReg, immediate = 0, labelSymbol = elseLabel), null)
+            if(useCmpi) {
+                result += IRCodeChunk(null, null).also {
+                    it += IRInstruction(Opcode.CMPI, branchDt, reg1=compResultReg, immediate = 0)
+                    it += IRInstruction(elseBranch, labelSymbol = elseLabel)
+                }
+            } else
+                addInstr(result, IRInstruction(elseBranch, branchDt, reg1=compResultReg, immediate = 0, labelSymbol = elseLabel), null)
             result += translateNode(ifElse.ifScope)
             addInstr(result, IRInstruction(Opcode.JUMP, labelSymbol = afterIfLabel), null)
             result += labelFirstChunk(translateNode(ifElse.elseScope), elseLabel)
@@ -1165,31 +1258,12 @@ class IRCodeGen(
 
     private fun translateIfElseNonZeroComparison(ifElse: PtIfElse, irDtLeft: IRDataType, signed: Boolean): IRCodeChunks {
         val result = mutableListOf<IRCodeChunkBase>()
-        val elseBranchOpcode: Opcode
         val elseBranchFirstReg: Int
         val elseBranchSecondReg: Int
         val branchDt: IRDataType
         val condition = ifElse.condition as? PtBinaryExpression
         if(condition==null) {
-            if(irDtLeft==IRDataType.FLOAT)
-                throw AssemblyError("condition value should not be float")
-            val tr = expressionEval.translateExpression(ifElse.condition)
-            result += tr.chunks
-            if(ifElse.elseScope.children.isNotEmpty()) {
-                val elseLabel = createLabelName()
-                val afterIfLabel = createLabelName()
-                addInstr(result, IRInstruction(Opcode.BEQ, irDtLeft, reg1=tr.resultReg, immediate = 0, labelSymbol = elseLabel), null)
-                result += translateNode(ifElse.ifScope)
-                addInstr(result, IRInstruction(Opcode.JUMP, labelSymbol = afterIfLabel), null)
-                result += labelFirstChunk(translateNode(ifElse.elseScope), elseLabel)
-                result += IRCodeChunk(afterIfLabel, null)
-            } else {
-                val afterIfLabel = createLabelName()
-                addInstr(result, IRInstruction(Opcode.BEQ, irDtLeft, reg1=tr.resultReg, immediate = 0, labelSymbol = afterIfLabel), null)
-                result += translateNode(ifElse.ifScope)
-                result += IRCodeChunk(afterIfLabel, null)
-            }
-            return result
+            throw AssemblyError("if-else condition is not a binaryexpression, should have been converted?")
         } else {
             if (irDtLeft == IRDataType.FLOAT) {
                 val leftTr = expressionEval.translateExpression(condition.left)
@@ -1197,35 +1271,35 @@ class IRCodeGen(
                 val rightTr = expressionEval.translateExpression(condition.right)
                 addToResult(result, rightTr, -1, rightTr.resultFpReg)
                 val compResultReg = registers.nextFree()
-                addInstr(
-                    result,
-                    IRInstruction(
-                        Opcode.FCOMP,
-                        IRDataType.FLOAT,
-                        reg1 = compResultReg,
-                        fpReg1 = leftTr.resultFpReg,
-                        fpReg2 = rightTr.resultFpReg
-                    ),
-                    null
-                )
-                val elseBranch = when (condition.operator) {
-                    "==" -> Opcode.BNE
-                    "!=" -> Opcode.BEQ
-                    "<" -> Opcode.BGES
-                    ">" -> Opcode.BLES
-                    "<=" -> Opcode.BGTS
-                    ">=" -> Opcode.BLTS
+                addInstr(result, IRInstruction(Opcode.FCOMP, IRDataType.FLOAT, reg1 = compResultReg, fpReg1 = leftTr.resultFpReg, fpReg2 = rightTr.resultFpReg), null)
+                val elseBranch: Opcode
+                var useCmpi = false     // for the branch opcodes that have been converted to CMPI + BSTxx form already
+                when (condition.operator) {
+                    "==" -> {
+                        elseBranch = Opcode.BSTNE
+                        useCmpi = true
+                    }
+                    "!=" -> {
+                        elseBranch = Opcode.BSTEQ
+                        useCmpi = true
+                    }
+                    "<" -> elseBranch = Opcode.BGES
+                    ">" -> elseBranch = Opcode.BLES
+                    "<=" -> elseBranch = Opcode.BGTS
+                    ">=" -> elseBranch = Opcode.BLTS
                     else -> throw AssemblyError("weird operator")
                 }
                 if (ifElse.elseScope.children.isNotEmpty()) {
                     // if and else parts
                     val elseLabel = createLabelName()
                     val afterIfLabel = createLabelName()
-                    addInstr(
-                        result,
-                        IRInstruction(elseBranch, IRDataType.BYTE, reg1 = compResultReg, immediate = 0, labelSymbol = elseLabel),
-                        null
-                    )
+                    if(useCmpi) {
+                        result += IRCodeChunk(null, null).also {
+                            it += IRInstruction(Opcode.CMPI, IRDataType.BYTE, reg1 = compResultReg, immediate = 0)
+                            it += IRInstruction(elseBranch, labelSymbol = elseLabel)
+                        }
+                    } else
+                        addInstr(result, IRInstruction(elseBranch, IRDataType.BYTE, reg1 = compResultReg, immediate = 0, labelSymbol = elseLabel), null)
                     result += translateNode(ifElse.ifScope)
                     addInstr(result, IRInstruction(Opcode.JUMP, labelSymbol = afterIfLabel), null)
                     result += labelFirstChunk(translateNode(ifElse.elseScope), elseLabel)
@@ -1233,11 +1307,13 @@ class IRCodeGen(
                 } else {
                     // only if part
                     val afterIfLabel = createLabelName()
-                    addInstr(
-                        result,
-                        IRInstruction(elseBranch, IRDataType.BYTE, reg1 = compResultReg, immediate = 0, labelSymbol = afterIfLabel),
-                        null
-                    )
+                    if(useCmpi) {
+                        result += IRCodeChunk(null, null).also {
+                            it += IRInstruction(Opcode.CMPI, IRDataType.BYTE, reg1 = compResultReg, immediate = 0)
+                            it += IRInstruction(elseBranch, labelSymbol = afterIfLabel)
+                        }
+                    } else
+                        addInstr(result, IRInstruction(elseBranch, IRDataType.BYTE, reg1 = compResultReg, immediate = 0, labelSymbol = afterIfLabel), null)
                     result += translateNode(ifElse.ifScope)
                     result += IRCodeChunk(afterIfLabel, null)
                 }
@@ -1248,26 +1324,34 @@ class IRCodeGen(
                 addToResult(result, leftTr, leftTr.resultReg, -1)
                 val number = (condition.right as? PtNumber)?.number?.toInt()
                 if (number!=null) {
-                    elseBranchOpcode = when (condition.operator) {
-                        "==" -> Opcode.BNE
-                        "!=" -> Opcode.BEQ
-                        "<" -> if(signed) Opcode.BGES else Opcode.BGE
-                        ">" -> if(signed) Opcode.BLES else Opcode.BLE
-                        "<=" -> if(signed) Opcode.BGTS else Opcode.BGT
-                        ">=" -> if(signed) Opcode.BLTS else Opcode.BLT
+                    val elseBranch: Opcode
+                    var useCmpi = false     // for the branch opcodes that have been converted to CMPI + BSTxx form already
+                    when (condition.operator) {
+                        "==" -> {
+                            elseBranch = Opcode.BSTNE
+                            useCmpi = true
+                        }
+                        "!=" -> {
+                            elseBranch = Opcode.BSTEQ
+                            useCmpi = true
+                        }
+                        "<" -> elseBranch = if(signed) Opcode.BGES else Opcode.BGE
+                        ">" -> elseBranch = if(signed) Opcode.BLES else Opcode.BLE
+                        "<=" -> elseBranch = if(signed) Opcode.BGTS else Opcode.BGT
+                        ">=" -> elseBranch = if(signed) Opcode.BLTS else Opcode.BLT
                         else -> throw AssemblyError("invalid comparison operator")
                     }
                     if (ifElse.elseScope.children.isNotEmpty()) {
                         // if and else parts
                         val elseLabel = createLabelName()
                         val afterIfLabel = createLabelName()
-                        addInstr(
-                            result, IRInstruction(
-                                elseBranchOpcode, branchDt,
-                                reg1 = leftTr.resultReg, immediate = number,
-                                labelSymbol = elseLabel
-                            ), null
-                        )
+                        if(useCmpi) {
+                            result += IRCodeChunk(null, null).also {
+                                it += IRInstruction(Opcode.CMPI, branchDt, reg1 = leftTr.resultReg, immediate = number)
+                                it += IRInstruction(elseBranch, labelSymbol = elseLabel)
+                            }
+                        } else
+                            addInstr(result, IRInstruction(elseBranch, branchDt, reg1 = leftTr.resultReg, immediate = number, labelSymbol = elseLabel), null)
                         result += translateNode(ifElse.ifScope)
                         addInstr(result, IRInstruction(Opcode.JUMP, labelSymbol = afterIfLabel), null)
                         result += labelFirstChunk(translateNode(ifElse.elseScope), elseLabel)
@@ -1275,52 +1359,56 @@ class IRCodeGen(
                     } else {
                         // only if part
                         val afterIfLabel = createLabelName()
-                        addInstr(
-                            result, IRInstruction(
-                                elseBranchOpcode, branchDt,
-                                reg1 = leftTr.resultReg, immediate = number,
-                                labelSymbol = afterIfLabel
-                            ), null
-                        )
+                        if(useCmpi) {
+                            result += IRCodeChunk(null, null).also {
+                                it += IRInstruction(Opcode.CMPI, branchDt, reg1 = leftTr.resultReg, immediate = number)
+                                it += IRInstruction(elseBranch, labelSymbol = afterIfLabel)
+                            }
+                        } else
+                            addInstr(result, IRInstruction(elseBranch, branchDt, reg1 = leftTr.resultReg, immediate = number, labelSymbol = afterIfLabel), null)
                         result += translateNode(ifElse.ifScope)
                         result += IRCodeChunk(afterIfLabel, null)
                     }
                 } else {
                     val rightTr = expressionEval.translateExpression(condition.right)
+                    val elseBranch: Opcode
+                    var useCmp = false
                     addToResult(result, rightTr, rightTr.resultReg, -1)
                     when (condition.operator) {
                         "==" -> {
-                            elseBranchOpcode = Opcode.BNER
+                            useCmp = true
+                            elseBranch = Opcode.BSTNE
                             elseBranchFirstReg = leftTr.resultReg
                             elseBranchSecondReg = rightTr.resultReg
                         }
                         "!=" -> {
-                            elseBranchOpcode = Opcode.BEQR
+                            useCmp = true
+                            elseBranch = Opcode.BSTEQ
                             elseBranchFirstReg = leftTr.resultReg
                             elseBranchSecondReg = rightTr.resultReg
                         }
                         "<" -> {
                             // else part when left >= right
-                            elseBranchOpcode = if (signed) Opcode.BGESR else Opcode.BGER
+                            elseBranch = if (signed) Opcode.BGESR else Opcode.BGER
                             elseBranchFirstReg = leftTr.resultReg
                             elseBranchSecondReg = rightTr.resultReg
                         }
                         ">" -> {
                             // else part when left <= right --> right >= left
-                            elseBranchOpcode = if (signed) Opcode.BGESR else Opcode.BGER
+                            elseBranch = if (signed) Opcode.BGESR else Opcode.BGER
                             elseBranchFirstReg = rightTr.resultReg
                             elseBranchSecondReg = leftTr.resultReg
                         }
                         "<=" -> {
                             // else part when left > right
-                            elseBranchOpcode = if (signed) Opcode.BGTSR else Opcode.BGTR
+                            elseBranch = if (signed) Opcode.BGTSR else Opcode.BGTR
                             elseBranchFirstReg = leftTr.resultReg
                             elseBranchSecondReg = rightTr.resultReg
                         }
 
                         ">=" -> {
                             // else part when left < right --> right > left
-                            elseBranchOpcode = if (signed) Opcode.BGTSR else Opcode.BGTR
+                            elseBranch = if (signed) Opcode.BGTSR else Opcode.BGTR
                             elseBranchFirstReg = rightTr.resultReg
                             elseBranchSecondReg = leftTr.resultReg
                         }
@@ -1330,13 +1418,14 @@ class IRCodeGen(
                         // if and else parts
                         val elseLabel = createLabelName()
                         val afterIfLabel = createLabelName()
-                        addInstr(
-                            result, IRInstruction(
-                                elseBranchOpcode, branchDt,
-                                reg1 = elseBranchFirstReg, reg2 = elseBranchSecondReg,
-                                labelSymbol = elseLabel
-                            ), null
-                        )
+                        if(useCmp) {
+                            result += IRCodeChunk(null,null).also {
+                                it += IRInstruction(Opcode.CMP, branchDt, reg1 = elseBranchFirstReg, reg2 = elseBranchSecondReg)
+                                it += IRInstruction(elseBranch, labelSymbol = elseLabel)
+                            }
+                        } else {
+                            addInstr(result, IRInstruction(elseBranch, branchDt, reg1 = elseBranchFirstReg, reg2 = elseBranchSecondReg, labelSymbol = elseLabel), null)
+                        }
                         result += translateNode(ifElse.ifScope)
                         addInstr(result, IRInstruction(Opcode.JUMP, labelSymbol = afterIfLabel), null)
                         result += labelFirstChunk(translateNode(ifElse.elseScope), elseLabel)
@@ -1344,13 +1433,14 @@ class IRCodeGen(
                     } else {
                         // only if part
                         val afterIfLabel = createLabelName()
-                        addInstr(
-                            result, IRInstruction(
-                                elseBranchOpcode, branchDt,
-                                reg1 = elseBranchFirstReg, reg2 = elseBranchSecondReg,
-                                labelSymbol = afterIfLabel
-                            ), null
-                        )
+                        if(useCmp) {
+                            result += IRCodeChunk(null,null).also {
+                                it += IRInstruction(Opcode.CMP, branchDt, reg1 = elseBranchFirstReg, reg2 = elseBranchSecondReg)
+                                it += IRInstruction(elseBranch, labelSymbol = afterIfLabel)
+                            }
+                        } else {
+                            addInstr(result, IRInstruction(elseBranch, branchDt, reg1 = elseBranchFirstReg, reg2 = elseBranchSecondReg, labelSymbol = afterIfLabel), null)
+                        }
                         result += translateNode(ifElse.ifScope)
                         result += IRCodeChunk(afterIfLabel, null)
                     }
@@ -1465,7 +1555,19 @@ class IRCodeGen(
                 val fixedIndex = constIntValue(array.index)
                 if(fixedIndex!=null) {
                     val offset = fixedIndex*itemsize
-                    addInstr(result, IRInstruction(operationMem, irDt, labelSymbol="$variable+$offset"), null)
+                    val indexReg = registers.nextFree()
+                    val dataReg = registers.nextFree()
+                    if(array.usesPointerVariable) {
+                        // we don't have an indirect dec/inc so do it via an intermediate register
+                        result += IRCodeChunk(null,null).also {
+                            it += IRInstruction(Opcode.LOAD, IRDataType.BYTE, reg1 = indexReg, immediate = offset)
+                            it += IRInstruction(Opcode.LOADIX, irDt, reg1 = dataReg, reg2 = indexReg, labelSymbol = variable)
+                            it += IRInstruction(operationRegister, irDt, reg1=dataReg)
+                            it += IRInstruction(Opcode.STOREIX, irDt, reg1 = dataReg, reg2 = indexReg, labelSymbol = variable)
+                        }
+                    } else {
+                        addInstr(result, IRInstruction(operationMem, irDt, labelSymbol = "$variable+$offset"), null)
+                    }
                 } else {
                     val indexTr = expressionEval.translateExpression(array.index)
                     addToResult(result, indexTr, indexTr.resultReg, -1)
@@ -1473,9 +1575,15 @@ class IRCodeGen(
                         result += multiplyByConst(IRDataType.BYTE, indexTr.resultReg, itemsize)
                     result += IRCodeChunk(null, null).also {
                         val incReg = registers.nextFree()
-                        it += IRInstruction(Opcode.LOADX, irDt, reg1=incReg, reg2=indexTr.resultReg, labelSymbol=variable)
-                        it += IRInstruction(operationRegister, irDt, reg1=incReg)
-                        it += IRInstruction(Opcode.STOREX, irDt, reg1=incReg, reg2=indexTr.resultReg, labelSymbol=variable)
+                        if(array.usesPointerVariable) {
+                            it += IRInstruction(Opcode.LOADIX, irDt, reg1=incReg, reg2=indexTr.resultReg, labelSymbol=variable)
+                            it += IRInstruction(operationRegister, irDt, reg1=incReg)
+                            it += IRInstruction(Opcode.STOREIX, irDt, reg1=incReg, reg2=indexTr.resultReg, labelSymbol=variable)
+                        } else {
+                            it += IRInstruction(Opcode.LOADX, irDt, reg1=incReg, reg2=indexTr.resultReg, labelSymbol=variable)
+                            it += IRInstruction(operationRegister, irDt, reg1=incReg)
+                            it += IRInstruction(Opcode.STOREX, irDt, reg1=incReg, reg2=indexTr.resultReg, labelSymbol=variable)
+                        }
                     }
                 }
             } else
@@ -1503,12 +1611,12 @@ class IRCodeGen(
         addToResult(result, countTr, countTr.resultReg, -1)
         if(constIntValue(repeat.count)==null) {
             // check if the counter is already zero
-            addInstr(result, IRInstruction(Opcode.BEQ, irDt, reg1=countTr.resultReg, immediate = 0, labelSymbol = skipRepeatLabel), null)
+            addInstr(result, IRInstruction(Opcode.BSTEQ, labelSymbol = skipRepeatLabel), null)
         }
         result += labelFirstChunk(translateNode(repeat.statements), repeatLabel)
         result += IRCodeChunk(null, null).also {
-            it += IRInstruction(Opcode.DEC, irDt, reg1 = countTr.resultReg)
-            it += IRInstruction(Opcode.BNE, irDt, reg1 = countTr.resultReg, immediate = 0, labelSymbol = repeatLabel)
+            it += IRInstruction(Opcode.DEC, irDt, reg1 = countTr.resultReg)  // sets status bits
+            it += IRInstruction(Opcode.BSTNE, labelSymbol = repeatLabel)
         }
         result += IRCodeChunk(skipRepeatLabel, null)
         return result
@@ -1648,24 +1756,6 @@ class IRCodeGen(
 
     internal fun isOne(expression: PtExpression): Boolean = expression is PtNumber && expression.number==1.0
 
-    fun getReusableTempvar(scope: PtNamedNode, type: DataType): PtIdentifier {
-        val uniqueId = Pair(scope, type).hashCode().toUInt()
-        val tempvarname = "${scope.scopedName}.tempvar_${uniqueId}"
-        val tempvar = PtIdentifier(tempvarname, type, Position.DUMMY)
-        val staticVar = StStaticVariable(
-            tempvarname,
-            type,
-            null,
-            null,
-            null,
-            null,
-            ZeropageWish.DONTCARE,
-            tempvar
-        )
-        irSymbolTable.add(staticVar)
-        return tempvar
-    }
-
     fun makeSyscall(syscall: IMSyscall, params: List<Pair<IRDataType, Int>>, returns: Pair<IRDataType, Int>?, label: String?=null): IRCodeChunk {
         return IRCodeChunk(label, null).also {
             val args = params.map { (dt, reg)->

codeGenIntermediate/src/prog8/codegen/intermediate/IRPeepholeOptimizer.kt

@@ -45,6 +45,7 @@ class IRPeepholeOptimizer(private val irprog: IRProgram) {
                         val indexedInstructions = chunk1.instructions.withIndex()
                             .map { IndexedValue(it.index, it.value) }
                         val changed = removeNops(chunk1, indexedInstructions)
+                                || replaceConcatZeroMsbWithExt(chunk1, indexedInstructions)
                                 || removeDoubleLoadsAndStores(chunk1, indexedInstructions)       // TODO not yet implemented
                                 || removeUselessArithmetic(chunk1, indexedInstructions)
                                 || removeNeedlessCompares(chunk1, indexedInstructions)
@@ -63,6 +64,22 @@ class IRPeepholeOptimizer(private val irprog: IRProgram) {
         irprog.linkChunks()  // re-link
     }
 
+    private fun replaceConcatZeroMsbWithExt(chunk: IRCodeChunk, indexedInstructions: List<IndexedValue<IRInstruction>>): Boolean {
+        var changed = false
+        indexedInstructions.reversed().forEach { (idx, ins) ->
+            if (ins.opcode == Opcode.CONCAT) {
+                // if the previous instruction loads a zero in the msb, this can be turned into EXT.B instead
+                val prev = indexedInstructions[idx-1].value
+                if(prev.opcode==Opcode.LOAD && prev.immediate==0 && prev.reg1==ins.reg2) {
+                    chunk.instructions[idx] = IRInstruction(Opcode.EXT, IRDataType.BYTE, reg1 = ins.reg1, reg2 = ins.reg3)
+                    chunk.instructions.removeAt(idx-1)
+                    changed = true
+                }
+            }
+        }
+        return changed
+    }
+
     private fun removeEmptyChunks(sub: IRSubroutine) {
         if(sub.chunks.isEmpty())
             return
@@ -70,7 +87,7 @@ class IRPeepholeOptimizer(private val irprog: IRProgram) {
         /*
         Empty Code chunk with label ->
             If next chunk has no label -> move label to next chunk, remove original
-            If next chunk has label -> label name should be the same, remove original. Otherwise FOR NOW leave it in place. (TODO: merge both labels into 1)
+            If next chunk has label -> label name should be the same, remove original. Otherwise merge both labels into 1.
             If is last chunk -> keep chunk in place because of the label.
         Empty Code chunk without label ->
             should not have been generated! ERROR.
@@ -79,6 +96,7 @@ class IRPeepholeOptimizer(private val irprog: IRProgram) {
 
         val relabelChunks = mutableListOf<Pair<Int, String>>()
         val removeChunks = mutableListOf<Int>()
+        val replaceLabels = mutableMapOf<String, String>()
 
         sub.chunks.withIndex().forEach { (index, chunk) ->
             if(chunk is IRCodeChunk && chunk.instructions.isEmpty()) {
@@ -92,10 +110,18 @@ class IRPeepholeOptimizer(private val irprog: IRProgram) {
                             relabelChunks += Pair(index + 1, chunk.label!!)
                             removeChunks += index
                         } else {
-                            if (chunk.label == nextchunk.label)
-                                removeChunks += index
-                            else {
-                                // TODO: merge labels on same chunk
+                            // merge both labels into 1 except if this is the label chunk at the start of the subroutine
+                            if(index>0) {
+                                if (chunk.label == nextchunk.label)
+                                    removeChunks += index
+                                else {
+                                    removeChunks += index
+                                    replaceLabels[chunk.label!!] = nextchunk.label!!
+                                    replaceLabels.entries.forEach { (key, value) ->
+                                        if (value == chunk.label)
+                                            replaceLabels[key] = nextchunk.label!!
+                                    }
+                                }
                             }
                         }
                     }
@@ -105,10 +131,32 @@ class IRPeepholeOptimizer(private val irprog: IRProgram) {
 
         relabelChunks.forEach { (index, label) ->
             val chunk = IRCodeChunk(label, null)
-            chunk.instructions += sub.chunks[index].instructions
+            val subChunk = sub.chunks[index]
+            chunk.instructions += subChunk.instructions
+            if(subChunk is IRCodeChunk)
+                chunk.appendSrcPositions(subChunk.sourceLinesPositions)
             sub.chunks[index] = chunk
         }
         removeChunks.reversed().forEach { index -> sub.chunks.removeAt(index) }
+
+        sub.chunks.forEach { chunk ->
+            chunk.instructions.withIndex().forEach { (idx, instr) ->
+                instr.labelSymbol?.let {
+                    if(instr.opcode in OpcodesThatBranch) {
+                        replaceLabels.forEach { (from, to) ->
+                            if (it == from) {
+                                chunk.instructions[idx] = instr.copy(labelSymbol = to)
+                            }
+                            else {
+                                val actualPrefix = "$from."
+                                if (it.startsWith(actualPrefix))
+                                    chunk.instructions[idx] = instr.copy(labelSymbol = "$to.")
+                            }
+                        }
+                    }
+                }
+            }
+        }
     }
 
     private fun joinChunks(sub: IRSubroutine) {
@@ -140,6 +188,8 @@ class IRPeepholeOptimizer(private val irprog: IRProgram) {
                     if(mayJoinCodeChunks(lastChunk, candidate)) {
                         lastChunk.instructions += candidate.instructions
                         lastChunk.next = candidate.next
+                        if(lastChunk is IRCodeChunk)
+                            lastChunk.appendSrcPositions(candidate.sourceLinesPositions)
                     }
                     else
                         chunks += candidate
@@ -358,6 +408,9 @@ class IRPeepholeOptimizer(private val irprog: IRProgram) {
     }
 
     private fun removeDoubleLoadsAndStores(chunk: IRCodeChunk, indexedInstructions: List<IndexedValue<IRInstruction>>): Boolean {
+        return false
+
+/*
         var changed = false
         indexedInstructions.forEach { (idx, ins) ->
 
@@ -371,5 +424,6 @@ class IRPeepholeOptimizer(private val irprog: IRProgram) {
             // ...
         }
         return changed
+*/
     }
 }

codeGenIntermediate/src/prog8/codegen/intermediate/IRUnusedCodeRemover.kt

@@ -1,7 +1,7 @@
 package prog8.codegen.intermediate
 
 import prog8.code.core.IErrorReporter
-import prog8.code.core.SourceCode.Companion.libraryFilePrefix
+import prog8.code.core.SourceCode.Companion.LIBRARYFILEPREFIX
 import prog8.intermediate.*
 
 
@@ -25,18 +25,29 @@ class IRUnusedCodeRemover(
     }
 
     private fun pruneSymboltable(blockLabel: String) {
-        // we could clean up the SymbolTable as well, but ONLY if these symbols aren't referenced somewhere still in an instruction
+        // we could clean up the SymbolTable as well, but ONLY if these symbols aren't referenced somewhere still in an instruction or variable initializer value
         val prefix = "$blockLabel."
         val blockVars = irprog.st.allVariables().filter { it.name.startsWith(prefix) }
         blockVars.forEach { stVar ->
-            irprog. allSubs().flatMap { it.chunks }.forEach { chunk ->
+            irprog.allSubs().flatMap { it.chunks }.forEach { chunk ->
                 chunk.instructions.forEach { ins ->
                     if(ins.labelSymbol == stVar.name) {
-                        return
+                        return  // symbol occurs in an instruction
                     }
                 }
             }
+
+            irprog.st.allVariables().forEach { variable ->
+                val initValue = variable.onetimeInitializationArrayValue
+                if(!initValue.isNullOrEmpty()) {
+                    if(initValue.any {
+                        it.addressOfSymbol?.startsWith(blockLabel)==true
+                    })
+                        return   // symbol occurs in an initializer value (address-of this symbol)_
+                }
+            }
         }
+
         irprog.st.removeTree(blockLabel)
     }
 
@@ -50,9 +61,6 @@ class IRUnusedCodeRemover(
         irprog.blocks.forEach { block ->
             block.children.filterIsInstance<IRSubroutine>().reversed().forEach { sub ->
                 if(sub.isEmpty()) {
-                    if(!sub.position.file.startsWith(libraryFilePrefix)) {
-                        errors.warn("unused subroutine ${sub.label}", sub.position)
-                    }
                     block.children.remove(sub)
                     irprog.st.removeTree(sub.label)
                     numRemoved++
@@ -71,7 +79,7 @@ class IRUnusedCodeRemover(
         irprog.blocks.forEach { block ->
             block.children.filterIsInstance<IRAsmSubroutine>().reversed().forEach { sub ->
                 if(sub.isEmpty()) {
-                    if(!sub.position.file.startsWith(libraryFilePrefix)) {
+                    if(!sub.position.file.startsWith(LIBRARYFILEPREFIX)) {
                         errors.warn("unused asmsubroutine ${sub.label}", sub.position)
                     }
                     block.children.remove(sub)
@@ -207,9 +215,7 @@ class IRUnusedCodeRemover(
         return removeUnlinkedChunks(linkedChunks)
     }
 
-    private fun removeUnlinkedChunks(
-        linkedChunks: Set<IRCodeChunkBase>
-    ): Int {
+    private fun removeUnlinkedChunks(linkedChunks: Set<IRCodeChunkBase>): Int {
         var numRemoved = 0
         irprog.foreachSub { sub ->
             sub.chunks.withIndex().reversed().forEach { (index, chunk) ->

codeGenIntermediate/src/prog8/codegen/vm/VmCodeGen.kt

@@ -16,7 +16,7 @@ class VmCodeGen: ICodeGeneratorBackend {
         symbolTable: SymbolTable,
         options: CompilationOptions,
         errors: IErrorReporter
-    ): IAssemblyProgram? {
+    ): IAssemblyProgram {
         val irCodeGen = IRCodeGen(program, symbolTable, options, errors)
         val irProgram = irCodeGen.generate()
         return VmAssemblyProgram(irProgram.name, irProgram)

codeGenIntermediate/test/Dummies.kt

@@ -16,6 +16,8 @@ internal object DummyMemsizer : IMemSizer {
 }
 
 internal object DummyStringEncoder : IStringEncoding {
+    override val defaultEncoding: Encoding = Encoding.ISO
+
     override fun encodeString(str: String, encoding: Encoding): List<UByte> {
         return emptyList()
     }

codeGenIntermediate/test/TestIRPeepholeOpt.kt

@@ -18,6 +18,7 @@ class TestIRPeepholeOpt: FunSpec({
             CbmPrgLauncherType.NONE,
             ZeropageType.DONTUSE,
             emptyList(),
+            CompilationOptions.AllZeropageAllowed,
             floats = false,
             noSysInit = true,
             compTarget = target,
@@ -52,9 +53,9 @@ class TestIRPeepholeOpt: FunSpec({
 
     test("remove jmp to label below") {
         val c1 = IRCodeChunk("main.start", null)
-        c1 += IRInstruction(Opcode.JUMP, labelSymbol = "label")  // removed, but chunk stays because of label
+        c1 += IRInstruction(Opcode.JUMP, labelSymbol = "label")
         val c2 = IRCodeChunk("label", null)
-        c2 += IRInstruction(Opcode.JUMP, labelSymbol = "label2") // removed, but chunk stays because of label
+        c2 += IRInstruction(Opcode.JUMP, labelSymbol = "label2")
         c2 += IRInstruction(Opcode.NOP)  // removed
         val c3 = IRCodeChunk("label2", null)
         c3 += IRInstruction(Opcode.JUMP, labelSymbol = "label3")
@@ -66,15 +67,13 @@ class TestIRPeepholeOpt: FunSpec({
         irProg.chunks().flatMap { it.instructions }.size shouldBe 5
         val opt = IRPeepholeOptimizer(irProg)
         opt.optimize(true, ErrorReporterForTests())
-        irProg.chunks().size shouldBe 4
+        irProg.chunks().size shouldBe 3
         irProg.chunks()[0].label shouldBe "main.start"
-        irProg.chunks()[1].label shouldBe "label"
-        irProg.chunks()[2].label shouldBe "label2"
-        irProg.chunks()[3].label shouldBe "label3"
+        irProg.chunks()[1].label shouldBe "label2"
+        irProg.chunks()[2].label shouldBe "label3"
         irProg.chunks()[0].isEmpty() shouldBe true
-        irProg.chunks()[1].isEmpty() shouldBe true
-        irProg.chunks()[2].isEmpty() shouldBe false
-        irProg.chunks()[3].isEmpty() shouldBe true
+        irProg.chunks()[1].isEmpty() shouldBe false
+        irProg.chunks()[2].isEmpty() shouldBe true
         val instr = irProg.chunks().flatMap { it.instructions }
         instr.size shouldBe 2
         instr[0].opcode shouldBe Opcode.JUMP

codeGenIntermediate/test/TestVmCodeGen.kt

@@ -19,6 +19,7 @@ class TestVmCodeGen: FunSpec({
             CbmPrgLauncherType.NONE,
             ZeropageType.DONTUSE,
             zpReserved = emptyList(),
+            zpAllowed = CompilationOptions.AllZeropageAllowed,
             floats = true,
             noSysInit = false,
             compTarget = target,
@@ -41,7 +42,7 @@ class TestVmCodeGen: FunSpec({
 //}
         val codegen = VmCodeGen()
         val program = PtProgram("test", DummyMemsizer, DummyStringEncoder)
-        val block = PtBlock("main", null, false, false, false, PtBlock.BlockAlignment.NONE, SourceCode.Generated("test"), Position.DUMMY)
+        val block = PtBlock("main", null, false, false, false, false, PtBlock.BlockAlignment.NONE, SourceCode.Generated("test"), Position.DUMMY)
         val sub = PtSub("start", emptyList(), null, Position.DUMMY)
         sub.add(PtVariable("pi", DataType.UBYTE, ZeropageWish.DONTCARE, PtNumber(DataType.UBYTE, 0.0, Position.DUMMY), null, Position.DUMMY))
         sub.add(PtVariable("particleX", DataType.ARRAY_UB, ZeropageWish.DONTCARE, null, 3u, Position.DUMMY))
@@ -91,7 +92,7 @@ class TestVmCodeGen: FunSpec({
         program.add(block)
 
         // define the "cx16.r0" virtual register
-        val cx16block = PtBlock("cx16", null, false, false, false, PtBlock.BlockAlignment.NONE, SourceCode.Generated("test"), Position.DUMMY)
+        val cx16block = PtBlock("cx16", null, false, false, false, false, PtBlock.BlockAlignment.NONE, SourceCode.Generated("test"), Position.DUMMY)
         cx16block.add(PtMemMapped("r0", DataType.UWORD, 100u, null, Position.DUMMY))
         program.add(cx16block)
 
@@ -120,7 +121,7 @@ class TestVmCodeGen: FunSpec({
 //}
         val codegen = VmCodeGen()
         val program = PtProgram("test", DummyMemsizer, DummyStringEncoder)
-        val block = PtBlock("main", null, false, false, false, PtBlock.BlockAlignment.NONE, SourceCode.Generated("test"), Position.DUMMY)
+        val block = PtBlock("main", null, false, false, false, false, PtBlock.BlockAlignment.NONE, SourceCode.Generated("test"), Position.DUMMY)
         val sub = PtSub("start", emptyList(), null, Position.DUMMY)
         sub.add(PtVariable("f1", DataType.FLOAT, ZeropageWish.DONTCARE, null, null, Position.DUMMY))
         val if1 = PtIfElse(Position.DUMMY)
@@ -183,7 +184,7 @@ class TestVmCodeGen: FunSpec({
 //}
         val codegen = VmCodeGen()
         val program = PtProgram("test", DummyMemsizer, DummyStringEncoder)
-        val block = PtBlock("main", null, false, false, false, PtBlock.BlockAlignment.NONE, SourceCode.Generated("test"), Position.DUMMY)
+        val block = PtBlock("main", null, false, false, false, false, PtBlock.BlockAlignment.NONE, SourceCode.Generated("test"), Position.DUMMY)
         val sub = PtSub("start", emptyList(), null, Position.DUMMY)
         sub.add(PtVariable("f1", DataType.FLOAT, ZeropageWish.DONTCARE, null, null, Position.DUMMY))
         val if1 = PtIfElse(Position.DUMMY)
@@ -242,7 +243,7 @@ class TestVmCodeGen: FunSpec({
 //}
         val codegen = VmCodeGen()
         val program = PtProgram("test", DummyMemsizer, DummyStringEncoder)
-        val block = PtBlock("main", null, false, false, false, PtBlock.BlockAlignment.NONE, SourceCode.Generated("test"), Position.DUMMY)
+        val block = PtBlock("main", null, false, false, false, false, PtBlock.BlockAlignment.NONE, SourceCode.Generated("test"), Position.DUMMY)
         val sub = PtSub("start", emptyList(), null, Position.DUMMY)
         sub.add(PtVariable("f1", DataType.FLOAT, ZeropageWish.DONTCARE, null, null, Position.DUMMY))
         val if1 = PtIfElse(Position.DUMMY)
@@ -289,7 +290,7 @@ class TestVmCodeGen: FunSpec({
 //}
         val codegen = VmCodeGen()
         val program = PtProgram("test", DummyMemsizer, DummyStringEncoder)
-        val block = PtBlock("main", null, false, false, false, PtBlock.BlockAlignment.NONE, SourceCode.Generated("test"), Position.DUMMY)
+        val block = PtBlock("main", null, false, false, false, false, PtBlock.BlockAlignment.NONE, SourceCode.Generated("test"), Position.DUMMY)
         val sub = PtSub("start", emptyList(), null, Position.DUMMY)
         sub.add(PtVariable("sb1", DataType.BYTE, ZeropageWish.DONTCARE, null, null, Position.DUMMY))
         val if1 = PtIfElse(Position.DUMMY)
@@ -352,7 +353,7 @@ class TestVmCodeGen: FunSpec({
 //}
         val codegen = VmCodeGen()
         val program = PtProgram("test", DummyMemsizer, DummyStringEncoder)
-        val block = PtBlock("main", null, false, false, false, PtBlock.BlockAlignment.NONE, SourceCode.Generated("test"), Position.DUMMY)
+        val block = PtBlock("main", null, false, false, false, false, PtBlock.BlockAlignment.NONE, SourceCode.Generated("test"), Position.DUMMY)
         val sub = PtSub("start", emptyList(), null, Position.DUMMY)
         sub.add(PtVariable("sb1", DataType.BYTE, ZeropageWish.DONTCARE, null, null, Position.DUMMY))
         val if1 = PtIfElse(Position.DUMMY)
@@ -411,7 +412,7 @@ class TestVmCodeGen: FunSpec({
 //}
         val codegen = VmCodeGen()
         val program = PtProgram("test", DummyMemsizer, DummyStringEncoder)
-        val block = PtBlock("main", null, false, false, false, PtBlock.BlockAlignment.NONE, SourceCode.Generated("test"), Position.DUMMY)
+        val block = PtBlock("main", null, false, false, false, false, PtBlock.BlockAlignment.NONE, SourceCode.Generated("test"), Position.DUMMY)
         val sub = PtSub("start", emptyList(), null, Position.DUMMY)
         sub.add(PtVariable("ub1", DataType.UBYTE, ZeropageWish.DONTCARE, null, null, Position.DUMMY))
         val if1 = PtIfElse(Position.DUMMY)
@@ -451,7 +452,7 @@ class TestVmCodeGen: FunSpec({
 //}
         val codegen = VmCodeGen()
         val program = PtProgram("test", DummyMemsizer, DummyStringEncoder)
-        val block = PtBlock("main", null, false, false, false, PtBlock.BlockAlignment.NONE, SourceCode.Generated("test"), Position.DUMMY)
+        val block = PtBlock("main", null, false, false, false, false, PtBlock.BlockAlignment.NONE, SourceCode.Generated("test"), Position.DUMMY)
         val romsub = PtAsmSub("routine", 0x5000u, setOf(CpuRegister.Y), emptyList(), emptyList(), false, Position.DUMMY)
         block.add(romsub)
         val sub = PtSub("start", emptyList(), null, Position.DUMMY)
@@ -466,7 +467,11 @@ class TestVmCodeGen: FunSpec({
         val result = codegen.generate(program, st, options, errors) as VmAssemblyProgram
         val irChunks = (result.irProgram.blocks.first().children.single() as IRSubroutine).chunks
         irChunks.size shouldBe 1
-        val callInstr = irChunks.single().instructions.single()
+        irChunks[0].instructions.size shouldBe 2
+        val preparecallInstr = irChunks[0].instructions[0]
+        preparecallInstr.opcode shouldBe Opcode.PREPARECALL
+        preparecallInstr.immediate shouldBe 0
+        val callInstr = irChunks[0].instructions[1]
         callInstr.opcode shouldBe Opcode.CALL
         callInstr.address shouldBe 0x5000
     }

codeOptimizers/build.gradle

@@ -33,10 +33,10 @@ dependencies {
 sourceSets {
     main {
         java {
-            srcDirs = ["${project.projectDir}/src"]
+            srcDir "${project.projectDir}/src"
         }
         resources {
-            srcDirs = ["${project.projectDir}/res"]
+            srcDir "${project.projectDir}/res"
         }
     }
 }

codeOptimizers/src/prog8/optimizer/BinExprSplitter.kt

@@ -1,71 +0,0 @@
-package prog8.optimizer
-
-import prog8.ast.IStatementContainer
-import prog8.ast.Node
-import prog8.ast.Program
-import prog8.ast.expressions.BinaryExpression
-import prog8.ast.statements.AssignTarget
-import prog8.ast.statements.Assignment
-import prog8.ast.statements.AssignmentOrigin
-import prog8.ast.walk.AstWalker
-import prog8.ast.walk.IAstModification
-import prog8.code.core.AugmentAssignmentOperators
-import prog8.code.core.CompilationOptions
-import prog8.code.core.DataType
-import prog8.code.target.VMTarget
-
-
-class BinExprSplitter(private val program: Program, private val options: CompilationOptions) : AstWalker() {
-
-    override fun after(assignment: Assignment, parent: Node): Iterable<IAstModification> {
-
-        if(options.compTarget.name == VMTarget.NAME)
-            return noModifications  // don't split expressions when targeting the vm codegen, it handles nested expressions well
-
-        if(assignment.value.inferType(program) istype DataType.FLOAT && !options.optimizeFloatExpressions)
-            return noModifications
-
-        val binExpr = assignment.value as? BinaryExpression
-        if (binExpr != null) {
-
-            if(binExpr.operator in AugmentAssignmentOperators && isSimpleTarget(assignment.target)) {
-                if(assignment.target isSameAs binExpr.right)
-                    return noModifications
-                if(assignment.target isSameAs binExpr.left) {
-                    if(binExpr.right.isSimple)
-                        return noModifications
-                    val leftBx = binExpr.left as? BinaryExpression
-                    if(leftBx!=null && (!leftBx.left.isSimple || !leftBx.right.isSimple))
-                        return noModifications
-                    val rightBx = binExpr.right as? BinaryExpression
-                    if(rightBx!=null && (!rightBx.left.isSimple || !rightBx.right.isSimple))
-                        return noModifications
-                }
-
-                if(binExpr.right.isSimple) {
-                    val firstAssign = Assignment(assignment.target.copy(), binExpr.left, AssignmentOrigin.OPTIMIZER, binExpr.left.position)
-                    val targetExpr = assignment.target.toExpression()
-                    val augExpr = BinaryExpression(targetExpr, binExpr.operator, binExpr.right, binExpr.right.position)
-                    return listOf(
-                        IAstModification.ReplaceNode(binExpr, augExpr, assignment),
-                        IAstModification.InsertBefore(assignment, firstAssign, assignment.parent as IStatementContainer)
-                    )
-                }
-            }
-
-            // Further unraveling of binary expressions is really complicated here and
-            // often results in much bigger code, thereby defeating the purpose a bit.
-            // All in all this should probably be fixed in a better code generation backend
-            // that doesn't require this at all.
-        }
-
-        return noModifications
-    }
-
-    private fun isSimpleTarget(target: AssignTarget) =
-            if (target.identifier!=null || target.memoryAddress!=null)
-                !target.isIOAddress(options.compTarget.machine)
-            else
-                false
-
-}

codeOptimizers/src/prog8/optimizer/ConstantFoldingOptimizer.kt

@@ -2,7 +2,6 @@ package prog8.optimizer
 
 import prog8.ast.Node
 import prog8.ast.Program
-import prog8.ast.base.FatalAstException
 import prog8.ast.expressions.*
 import prog8.ast.maySwapOperandOrder
 import prog8.ast.statements.ForLoop
@@ -19,12 +18,13 @@ import kotlin.math.floor
 class ConstantFoldingOptimizer(private val program: Program) : AstWalker() {
 
     override fun before(memread: DirectMemoryRead, parent: Node): Iterable<IAstModification> {
-        // @( &thing )  -->  thing
+        // @( &thing )  -->  thing  (but only if thing is a byte type!)
         val addrOf = memread.addressExpression as? AddressOf
-        return if(addrOf!=null)
-            listOf(IAstModification.ReplaceNode(memread, addrOf.identifier, parent))
-        else
-            noModifications
+        if(addrOf!=null) {
+            if(addrOf.identifier.inferType(program).isBytes)
+                return listOf(IAstModification.ReplaceNode(memread, addrOf.identifier, parent))
+        }
+        return noModifications
     }
 
     override fun after(containment: ContainmentCheck, parent: Node): Iterable<IAstModification> {
@@ -86,7 +86,8 @@ class ConstantFoldingOptimizer(private val program: Program) : AstWalker() {
 
         if(expr.operator=="==" && rightconst!=null) {
             val leftExpr = expr.left as? BinaryExpression
-            if(leftExpr!=null) {
+            // only do this shuffling when the LHS is not a constant itself (otherwise problematic nested replacements)
+            if(leftExpr?.constValue(program) != null) {
                 val leftRightConst = leftExpr.right.constValue(program)
                 if(leftRightConst!=null) {
                     when (leftExpr.operator) {
@@ -183,10 +184,12 @@ class ConstantFoldingOptimizer(private val program: Program) : AstWalker() {
                         val newExpr = BinaryExpression(leftBinExpr.left, "*", constants, expr.position)
                         return listOf(IAstModification.ReplaceNode(expr, newExpr, parent))
                     } else if (leftBinExpr.operator=="/") {
-                        //  (X / C2) * rightConst   -->  X * (rightConst/C2)
-                        val constants = BinaryExpression(rightconst, "/", c2, c2.position)
-                        val newExpr = BinaryExpression(leftBinExpr.left, "*", constants, expr.position)
-                        return listOf(IAstModification.ReplaceNode(expr, newExpr, parent))
+                        if(expr.inferType(program).istype(DataType.FLOAT)) {
+                            //  (X / C2) * rightConst   -->  X * (rightConst/C2)    only valid for floating point
+                            val constants = BinaryExpression(rightconst, "/", c2, c2.position)
+                            val newExpr = BinaryExpression(leftBinExpr.left, "*", constants, expr.position)
+                            return listOf(IAstModification.ReplaceNode(expr, newExpr, parent))
+                        }
                     }
                 }
             }
@@ -194,7 +197,7 @@ class ConstantFoldingOptimizer(private val program: Program) : AstWalker() {
                 val c2 = leftBinExpr.right.constValue(program)
                 if(c2!=null && leftBinExpr.operator=="/") {
                     // (X / C1) / C2   -->  X / (C1*C2)
-                    // NOTE: do not optimize  (X * C1) / C2   -->  X * (C1/C2)  because this causes precision loss on integers
+                    // NOTE: do not optimize  (X * C1) / C2  for integers,  -->  X * (C1/C2)  because this causes precision loss on integers
                     val constants = BinaryExpression(c2, "*", rightconst, c2.position)
                     val newExpr = BinaryExpression(leftBinExpr.left, "/", constants, expr.position)
                     return listOf(IAstModification.ReplaceNode(expr, newExpr, parent))
@@ -235,6 +238,47 @@ class ConstantFoldingOptimizer(private val program: Program) : AstWalker() {
             }
         }
 
+        if(rightconst!=null && (expr.operator=="<<" || expr.operator==">>")) {
+            val dt = expr.left.inferType(program)
+            if(dt.isBytes && rightconst.number>=8) {
+                if(dt.istype(DataType.UBYTE)) {
+                    val zeroUB = NumericLiteral(DataType.UBYTE, 0.0, expr.position)
+                    modifications.add(IAstModification.ReplaceNode(expr, zeroUB, parent))
+                } else {
+                    if(leftconst!=null) {
+                        val zeroB = NumericLiteral(DataType.BYTE, 0.0, expr.position)
+                        val minusoneB = NumericLiteral(DataType.BYTE, -1.0, expr.position)
+                        if(leftconst.number<0.0) {
+                            if(expr.operator=="<<")
+                                modifications.add(IAstModification.ReplaceNode(expr, zeroB, parent))
+                            else
+                                modifications.add(IAstModification.ReplaceNode(expr, minusoneB, parent))
+                        } else {
+                            modifications.add(IAstModification.ReplaceNode(expr, zeroB, parent))
+                        }
+                    }
+                }
+            }
+            else if(dt.isWords && rightconst.number>=16) {
+                if(dt.istype(DataType.UWORD)) {
+                    val zeroUW = NumericLiteral(DataType.UWORD, 0.0, expr.position)
+                    modifications.add(IAstModification.ReplaceNode(expr, zeroUW, parent))
+                } else {
+                    if(leftconst!=null) {
+                        val zeroW = NumericLiteral(DataType.WORD, 0.0, expr.position)
+                        val minusoneW = NumericLiteral(DataType.WORD, -1.0, expr.position)
+                        if(leftconst.number<0.0) {
+                            if(expr.operator=="<<")
+                                modifications.add(IAstModification.ReplaceNode(expr, zeroW, parent))
+                            else
+                                modifications.add(IAstModification.ReplaceNode(expr, minusoneW, parent))
+                        } else {
+                            modifications.add(IAstModification.ReplaceNode(expr, zeroW, parent))
+                        }
+                    }
+                }
+            }
+        }
 
         return modifications
     }
@@ -344,7 +388,7 @@ class ConstantFoldingOptimizer(private val program: Program) : AstWalker() {
                         return listOf(IAstModification.ReplaceNode(forLoop.iterable, newIter, forLoop))
                 }
             }
-            else -> throw FatalAstException("invalid loopvar datatype $loopvar")
+            else -> { /* nothing for floats, these are not allowed in for loops and will give an error elsewhere */ }
         }
 
         return noModifications
@@ -484,7 +528,8 @@ class ConstantFoldingOptimizer(private val program: Program) : AstWalker() {
                     return IAstModification.ReplaceNode(expr, change, expr.parent)
                 }
             }
-            else if(expr.operator=="*" && subExpr.operator=="/") {
+            else if(expr.operator=="*" && subExpr.operator=="/" && subExpr.inferType(program).istype(DataType.FLOAT)) {
+                // division optimizations only valid for floats
                 if(leftIsConst) {
                     val change = if(subleftIsConst) {
                         // C1*(C2/V) -> (C1*C2)/V
@@ -587,5 +632,4 @@ class ConstantFoldingOptimizer(private val program: Program) : AstWalker() {
             return null
         }
     }
-
 }

codeOptimizers/src/prog8/optimizer/ConstantIdentifierReplacer.kt

@@ -28,6 +28,7 @@ class VarConstantValueTypeAdjuster(private val program: Program, private val err
                     errors.err("refused rounding of float to avoid loss of precision", decl.value!!.position)
                 } else {
                     // cast the numeric literal to the appropriate datatype of the variable
+                    declConstValue.linkParents(decl)
                     val cast = declConstValue.cast(decl.datatype)
                     if (cast.isValid)
                         return listOf(IAstModification.ReplaceNode(decl.value!!, cast.valueOrZero(), decl))
@@ -251,7 +252,16 @@ internal class ConstantIdentifierReplacer(private val program: Program, private
             return noModifications
         }
 
-        if(decl.type== VarDeclType.CONST || decl.type== VarDeclType.VAR) {
+        if(decl.isArray && decl.type==VarDeclType.MEMORY) {
+            val memaddr = decl.value?.constValue(program)
+            if(memaddr!=null && memaddr !== decl.value) {
+                return listOf(IAstModification.SetExpression(
+                    { decl.value = it }, memaddr, decl
+                ))
+            }
+        }
+
+        if(decl.type==VarDeclType.CONST || decl.type==VarDeclType.VAR) {
             if(decl.isArray){
                 val arraysize = decl.arraysize
                 if(arraysize==null) {
@@ -276,101 +286,10 @@ internal class ConstantIdentifierReplacer(private val program: Program, private
                         return listOf(IAstModification.ReplaceNode(decl.value!!, newValue, decl))
                     }
                 }
-                DataType.ARRAY_UB, DataType.ARRAY_B, DataType.ARRAY_UW, DataType.ARRAY_W, DataType.ARRAY_W_SPLIT, DataType.ARRAY_UW_SPLIT -> {
-                    val rangeExpr = decl.value as? RangeExpression
-                    if(rangeExpr!=null) {
-                        // convert the initializer range expression to an actual array
-                        val declArraySize = decl.arraysize?.constIndex()
-                        if(declArraySize!=null && declArraySize!=rangeExpr.size())
-                            errors.err("range expression size (${rangeExpr.size()}) doesn't match declared array size ($declArraySize)", decl.value?.position!!)
-                        val constRange = rangeExpr.toConstantIntegerRange()
-                        if(constRange!=null) {
-                            val eltType = rangeExpr.inferType(program).getOr(DataType.UBYTE)
-                            val newValue = if(eltType in ByteDatatypes) {
-                                ArrayLiteral(InferredTypes.InferredType.known(decl.datatype),
-                                        constRange.map { NumericLiteral(eltType, it.toDouble(), decl.value!!.position) }.toTypedArray(),
-                                        position = decl.value!!.position)
-                            } else {
-                                ArrayLiteral(InferredTypes.InferredType.known(decl.datatype),
-                                        constRange.map { NumericLiteral(eltType, it.toDouble(), decl.value!!.position) }.toTypedArray(),
-                                        position = decl.value!!.position)
-                            }
-                            return listOf(IAstModification.ReplaceNode(decl.value!!, newValue, decl))
-                        }
-                    }
-                    val numericLv = decl.value as? NumericLiteral
-                    if(numericLv!=null && numericLv.type== DataType.FLOAT)
-                        errors.err("arraysize requires only integers here", numericLv.position)
-                    val size = decl.arraysize?.constIndex() ?: 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 { NumericLiteral(ArrayToElementTypes.getValue(decl.datatype), it.toDouble(), numericLv.position) }.toTypedArray<Expression>()
-                        val refValue = ArrayLiteral(InferredTypes.InferredType.known(decl.datatype), array, position = numericLv.position)
-                        return listOf(IAstModification.ReplaceNode(decl.value!!, refValue, decl))
-                    }
-                }
-                DataType.ARRAY_F -> {
-                    val rangeExpr = decl.value as? RangeExpression
-                    if(rangeExpr!=null) {
-                        // convert the initializer range expression to an actual array of floats
-                        val declArraySize = decl.arraysize?.constIndex()
-                        if(declArraySize!=null && declArraySize!=rangeExpr.size())
-                            errors.err("range expression size (${rangeExpr.size()}) doesn't match declared array size ($declArraySize)", decl.value?.position!!)
-                        val constRange = rangeExpr.toConstantIntegerRange()
-                        if(constRange!=null) {
-                            val newValue = ArrayLiteral(InferredTypes.InferredType.known(DataType.ARRAY_F),
-                                    constRange.map { NumericLiteral(DataType.FLOAT, it.toDouble(), decl.value!!.position) }.toTypedArray(),
-                                    position = decl.value!!.position)
-                            return listOf(IAstModification.ReplaceNode(decl.value!!, newValue, decl))
-                        }
-                    }
-
-                    val numericLv = decl.value as? NumericLiteral
-                    val size = decl.arraysize?.constIndex() ?: return noModifications
-                    if(rangeExpr==null && numericLv!=null) {
-                        // arraysize initializer is a single int, and we know the size.
-                        val fillvalue = numericLv.number
-                        if (fillvalue < compTarget.machine.FLOAT_MAX_NEGATIVE || fillvalue > compTarget.machine.FLOAT_MAX_POSITIVE)
-                            errors.err("float value overflow", numericLv.position)
-                        else {
-                            // create the array itself, filled with the fillvalue.
-                            val array = Array(size) {fillvalue}.map { NumericLiteral(DataType.FLOAT, it, numericLv.position) }.toTypedArray<Expression>()
-                            val refValue = ArrayLiteral(InferredTypes.InferredType.known(DataType.ARRAY_F), array, position = numericLv.position)
-                            return listOf(IAstModification.ReplaceNode(decl.value!!, refValue, decl))
-                        }
-                    }
-                }
-                DataType.ARRAY_BOOL -> {
-                    val numericLv = decl.value as? NumericLiteral
-                    val size = decl.arraysize?.constIndex() ?: return noModifications
-                    if(numericLv!=null) {
-                        // arraysize initializer is a single int, and we know the size.
-                        val fillvalue = if(numericLv.number==0.0) 0.0 else 1.0
-                        val array = Array(size) {fillvalue}.map { NumericLiteral(DataType.UBYTE, fillvalue, numericLv.position) }.toTypedArray<Expression>()
-                        val refValue = ArrayLiteral(InferredTypes.InferredType.known(DataType.ARRAY_BOOL), array, position = numericLv.position)
-                        return listOf(IAstModification.ReplaceNode(decl.value!!, refValue, decl))
-                    }
+                in ArrayDatatypes -> {
+                    val replacedArrayInitializer = createConstArrayInitializerValue(decl)
+                    if(replacedArrayInitializer!=null)
+                        return listOf(IAstModification.ReplaceNode(decl.value!!, replacedArrayInitializer, decl))
                 }
                 else -> {
                     // nothing to do for this type
@@ -380,4 +299,112 @@ internal class ConstantIdentifierReplacer(private val program: Program, private
 
         return noModifications
     }
+
+    private fun createConstArrayInitializerValue(decl: VarDecl): ArrayLiteral? {
+
+        if(decl.type==VarDeclType.MEMORY)
+            return null     // memory mapped arrays can never have an initializer value other than the address where they're mapped.
+
+        // convert the initializer range expression from a range or int, to an actual array.
+        when(decl.datatype) {
+            DataType.ARRAY_UB, DataType.ARRAY_B, DataType.ARRAY_UW, DataType.ARRAY_W, DataType.ARRAY_W_SPLIT, DataType.ARRAY_UW_SPLIT -> {
+                val rangeExpr = decl.value as? RangeExpression
+                if(rangeExpr!=null) {
+                    val constRange = rangeExpr.toConstantIntegerRange()
+                    if(constRange?.isEmpty()==true) {
+                        if(constRange.first>constRange.last && constRange.step>=0)
+                            errors.err("descending range with positive step", decl.value?.position!!)
+                        else if(constRange.first<constRange.last && constRange.step<=0)
+                            errors.err("ascending range with negative step", decl.value?.position!!)
+                    }
+                    val declArraySize = decl.arraysize?.constIndex()
+                    if(declArraySize!=null && declArraySize!=rangeExpr.size())
+                        errors.err("range expression size (${rangeExpr.size()}) doesn't match declared array size ($declArraySize)", decl.value?.position!!)
+                    if(constRange!=null) {
+                        val eltType = rangeExpr.inferType(program).getOr(DataType.UBYTE)
+                        return if(eltType in ByteDatatypes) {
+                            ArrayLiteral(InferredTypes.InferredType.known(decl.datatype),
+                                constRange.map { NumericLiteral(eltType, it.toDouble(), decl.value!!.position) }.toTypedArray(),
+                                position = decl.value!!.position)
+                        } else {
+                            ArrayLiteral(InferredTypes.InferredType.known(decl.datatype),
+                                constRange.map { NumericLiteral(eltType, it.toDouble(), decl.value!!.position) }.toTypedArray(),
+                                position = decl.value!!.position)
+                        }
+                    }
+                }
+                val numericLv = decl.value as? NumericLiteral
+                if(numericLv!=null && numericLv.type== DataType.FLOAT)
+                    errors.err("arraysize requires only integers here", numericLv.position)
+                val size = decl.arraysize?.constIndex() ?: return null
+                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 { NumericLiteral(ArrayToElementTypes.getValue(decl.datatype), it.toDouble(), numericLv.position) }.toTypedArray<Expression>()
+                    return ArrayLiteral(InferredTypes.InferredType.known(decl.datatype), array, position = numericLv.position)
+                }
+            }
+            DataType.ARRAY_F -> {
+                val rangeExpr = decl.value as? RangeExpression
+                if(rangeExpr!=null) {
+                    // convert the initializer range expression to an actual array of floats
+                    val declArraySize = decl.arraysize?.constIndex()
+                    if(declArraySize!=null && declArraySize!=rangeExpr.size())
+                        errors.err("range expression size (${rangeExpr.size()}) doesn't match declared array size ($declArraySize)", decl.value?.position!!)
+                    val constRange = rangeExpr.toConstantIntegerRange()
+                    if(constRange!=null) {
+                        return ArrayLiteral(InferredTypes.InferredType.known(DataType.ARRAY_F),
+                            constRange.map { NumericLiteral(DataType.FLOAT, it.toDouble(), decl.value!!.position) }.toTypedArray(),
+                            position = decl.value!!.position)
+                    }
+                }
+
+                val numericLv = decl.value as? NumericLiteral
+                val size = decl.arraysize?.constIndex() ?: return null
+                if(rangeExpr==null && numericLv!=null) {
+                    // arraysize initializer is a single int, and we know the size.
+                    val fillvalue = numericLv.number
+                    if (fillvalue < compTarget.machine.FLOAT_MAX_NEGATIVE || fillvalue > compTarget.machine.FLOAT_MAX_POSITIVE)
+                        errors.err("float value overflow", numericLv.position)
+                    else {
+                        // create the array itself, filled with the fillvalue.
+                        val array = Array(size) {fillvalue}.map { NumericLiteral(DataType.FLOAT, it, numericLv.position) }.toTypedArray<Expression>()
+                        return ArrayLiteral(InferredTypes.InferredType.known(DataType.ARRAY_F), array, position = numericLv.position)
+                    }
+                }
+            }
+            DataType.ARRAY_BOOL -> {
+                val numericLv = decl.value as? NumericLiteral
+                val size = decl.arraysize?.constIndex() ?: return null
+                if(numericLv!=null) {
+                    // arraysize initializer is a single int, and we know the size.
+                    val fillvalue = if(numericLv.number==0.0) 0.0 else 1.0
+                    val array = Array(size) {fillvalue}.map { NumericLiteral(DataType.UBYTE, fillvalue, numericLv.position) }.toTypedArray<Expression>()
+                    return ArrayLiteral(InferredTypes.InferredType.known(DataType.ARRAY_BOOL), array, position = numericLv.position)
+                }
+            }
+            else -> return null
+        }
+        return null
+    }
 }

codeOptimizers/src/prog8/optimizer/Extensions.kt

@@ -65,9 +65,3 @@ fun Program.simplifyExpressions(errors: IErrorReporter, target: ICompilationTarg
     opti.visit(this)
     return opti.applyModifications()
 }
-
-fun Program.splitBinaryExpressions(options: CompilationOptions) : Int {
-    val opti = BinExprSplitter(this, options)
-    opti.visit(this)
-    return opti.applyModifications()
-}

codeOptimizers/src/prog8/optimizer/Inliner.kt

@@ -34,85 +34,100 @@ class Inliner(private val program: Program, private val options: CompilationOpti
                 val containsSubsOrVariables = subroutine.statements.any { it is VarDecl || it is Subroutine}
                 if(!containsSubsOrVariables) {
                     if(subroutine.statements.size==1 || (subroutine.statements.size==2 && isEmptyReturn(subroutine.statements[1]))) {
-                        // subroutine is possible candidate to be inlined
-                        subroutine.inline =
-                            when(val stmt=subroutine.statements[0]) {
-                                is Return -> {
-                                    if(stmt.value is NumericLiteral)
-                                        true
-                                    else if(stmt.value==null)
-                                        true
-                                    else if (stmt.value is IdentifierReference) {
-                                        makeFullyScoped(stmt.value as IdentifierReference)
-                                        true
-                                    } else if(stmt.value!! is IFunctionCall && (stmt.value as IFunctionCall).args.size<=1 && (stmt.value as IFunctionCall).args.all { it is NumericLiteral || it is IdentifierReference }) {
-                                        when (stmt.value) {
-                                            is BuiltinFunctionCall -> {
-                                                makeFullyScoped(stmt.value as BuiltinFunctionCall)
-                                                true
+                        if(subroutine !== program.entrypoint) {
+                            // subroutine is possible candidate to be inlined
+                            subroutine.inline =
+                                when (val stmt = subroutine.statements[0]) {
+                                    is Return -> {
+                                        if (stmt.value is NumericLiteral)
+                                            true
+                                        else if (stmt.value == null)
+                                            true
+                                        else if (stmt.value is IdentifierReference) {
+                                            makeFullyScoped(stmt.value as IdentifierReference)
+                                            true
+                                        } else if (stmt.value!! is IFunctionCall && (stmt.value as IFunctionCall).args.size <= 1 && (stmt.value as IFunctionCall).args.all { it is NumericLiteral || it is IdentifierReference }) {
+                                            when (stmt.value) {
+                                                is BuiltinFunctionCall -> {
+                                                    makeFullyScoped(stmt.value as BuiltinFunctionCall)
+                                                    true
+                                                }
+
+                                                is FunctionCallExpression -> {
+                                                    makeFullyScoped(stmt.value as FunctionCallExpression)
+                                                    true
+                                                }
+
+                                                else -> false
                                             }
-                                            is FunctionCallExpression -> {
-                                                makeFullyScoped(stmt.value as FunctionCallExpression)
-                                                true
-                                            }
-                                            else -> false
-                                        }
-                                    } else
-                                        false
-                                }
-                                is Assignment -> {
-                                    if(stmt.value.isSimple) {
-                                        val targetInline =
-                                            if(stmt.target.identifier!=null) {
-                                                makeFullyScoped(stmt.target.identifier!!)
-                                                true
-                                            } else if(stmt.target.memoryAddress?.addressExpression is NumericLiteral || stmt.target.memoryAddress?.addressExpression is IdentifierReference) {
-                                                if(stmt.target.memoryAddress?.addressExpression is IdentifierReference)
-                                                    makeFullyScoped(stmt.target.memoryAddress?.addressExpression as IdentifierReference)
-                                                true
-                                            } else
-                                                false
-                                        val valueInline =
-                                            if(stmt.value is IdentifierReference) {
-                                                makeFullyScoped(stmt.value as IdentifierReference)
-                                                true
-                                            } else if((stmt.value as? DirectMemoryRead)?.addressExpression is NumericLiteral || (stmt.value as? DirectMemoryRead)?.addressExpression is IdentifierReference) {
-                                                if((stmt.value as? DirectMemoryRead)?.addressExpression is IdentifierReference)
-                                                    makeFullyScoped((stmt.value as? DirectMemoryRead)?.addressExpression as IdentifierReference)
-                                                true
-                                            } else
-                                                false
-                                        targetInline || valueInline
-                                    } else
-                                        false
-                                }
-                                is BuiltinFunctionCallStatement -> {
-                                    val inline = stmt.args.size<=1 && stmt.args.all { it is NumericLiteral || it is IdentifierReference }
-                                    if(inline)
-                                        makeFullyScoped(stmt)
-                                    inline
-                                }
-                                is FunctionCallStatement -> {
-                                    val inline = stmt.args.size<=1 && stmt.args.all { it is NumericLiteral || it is IdentifierReference }
-                                    if(inline)
-                                        makeFullyScoped(stmt)
-                                    inline
-                                }
-                                is PostIncrDecr -> {
-                                    if(stmt.target.identifier!=null) {
-                                        makeFullyScoped(stmt.target.identifier!!)
-                                        true
+                                        } else
+                                            false
                                     }
-                                    else if(stmt.target.memoryAddress?.addressExpression is NumericLiteral || stmt.target.memoryAddress?.addressExpression is IdentifierReference) {
-                                        if(stmt.target.memoryAddress?.addressExpression is IdentifierReference)
-                                            makeFullyScoped(stmt.target.memoryAddress?.addressExpression as IdentifierReference)
-                                        true
-                                    } else
-                                        false
+
+                                    is Assignment -> {
+                                        if (stmt.value.isSimple) {
+                                            val targetInline =
+                                                if (stmt.target.identifier != null) {
+                                                    makeFullyScoped(stmt.target.identifier!!)
+                                                    true
+                                                } else if (stmt.target.memoryAddress?.addressExpression is NumericLiteral || stmt.target.memoryAddress?.addressExpression is IdentifierReference) {
+                                                    if (stmt.target.memoryAddress?.addressExpression is IdentifierReference)
+                                                        makeFullyScoped(stmt.target.memoryAddress?.addressExpression as IdentifierReference)
+                                                    true
+                                                } else
+                                                    false
+                                            val valueInline =
+                                                if (stmt.value is IdentifierReference) {
+                                                    makeFullyScoped(stmt.value as IdentifierReference)
+                                                    true
+                                                } else if ((stmt.value as? DirectMemoryRead)?.addressExpression is NumericLiteral || (stmt.value as? DirectMemoryRead)?.addressExpression is IdentifierReference) {
+                                                    if ((stmt.value as? DirectMemoryRead)?.addressExpression is IdentifierReference)
+                                                        makeFullyScoped((stmt.value as? DirectMemoryRead)?.addressExpression as IdentifierReference)
+                                                    true
+                                                } else
+                                                    false
+                                            targetInline || valueInline
+                                        } else
+                                            false
+                                    }
+
+                                    is BuiltinFunctionCallStatement -> {
+                                        val inline =
+                                            stmt.args.size <= 1 && stmt.args.all { it is NumericLiteral || it is IdentifierReference }
+                                        if (inline)
+                                            makeFullyScoped(stmt)
+                                        inline
+                                    }
+
+                                    is FunctionCallStatement -> {
+                                        val inline =
+                                            stmt.args.size <= 1 && stmt.args.all { it is NumericLiteral || it is IdentifierReference }
+                                        if (inline)
+                                            makeFullyScoped(stmt)
+                                        inline
+                                    }
+
+                                    is PostIncrDecr -> {
+                                        if (stmt.target.identifier != null) {
+                                            makeFullyScoped(stmt.target.identifier!!)
+                                            true
+                                        } else if (stmt.target.memoryAddress?.addressExpression is NumericLiteral || stmt.target.memoryAddress?.addressExpression is IdentifierReference) {
+                                            if (stmt.target.memoryAddress?.addressExpression is IdentifierReference)
+                                                makeFullyScoped(stmt.target.memoryAddress?.addressExpression as IdentifierReference)
+                                            true
+                                        } else
+                                            false
+                                    }
+
+                                    is Jump -> true
+                                    else -> false
                                 }
-                                is Jump -> true
-                                else -> false
-                            }
+                        }
+                    }
+
+                    if(subroutine.inline && subroutine.statements.size>1) {
+                        require(subroutine.statements.size==2 && isEmptyReturn(subroutine.statements[1]))
+                        subroutine.statements.removeLast()      // get rid of the Return, to be able to inline the (single) statement preceding it.
                     }
                 }
             }
@@ -129,16 +144,20 @@ class Inliner(private val program: Program, private val options: CompilationOpti
 
         private fun makeFullyScoped(call: BuiltinFunctionCallStatement) {
             val scopedArgs = makeScopedArgs(call.args)
-            val scopedCall = BuiltinFunctionCallStatement(call.target.copy(), scopedArgs.toMutableList(), call.position)
-            modifications += IAstModification.ReplaceNode(call, scopedCall, call.parent)
+            if(scopedArgs.any()) {
+                val scopedCall = BuiltinFunctionCallStatement(call.target.copy(), scopedArgs.toMutableList(), call.position)
+                modifications += IAstModification.ReplaceNode(call, scopedCall, call.parent)
+            }
         }
 
         private fun makeFullyScoped(call: FunctionCallStatement) {
             call.target.targetSubroutine(program)?.let { sub ->
                 val scopedName = IdentifierReference(sub.scopedName, call.target.position)
                 val scopedArgs = makeScopedArgs(call.args)
-                val scopedCall = FunctionCallStatement(scopedName, scopedArgs.toMutableList(), call.void, call.position)
-                modifications += IAstModification.ReplaceNode(call, scopedCall, call.parent)
+                if(scopedArgs.any()) {
+                    val scopedCall = FunctionCallStatement(scopedName, scopedArgs.toMutableList(), call.void, call.position)
+                    modifications += IAstModification.ReplaceNode(call, scopedCall, call.parent)
+                }
             }
         }
 
@@ -146,8 +165,10 @@ class Inliner(private val program: Program, private val options: CompilationOpti
             call.target.targetSubroutine(program)?.let { sub ->
                 val scopedName = IdentifierReference(sub.scopedName, call.target.position)
                 val scopedArgs = makeScopedArgs(call.args)
-                val scopedCall = BuiltinFunctionCall(scopedName, scopedArgs.toMutableList(), call.position)
-                modifications += IAstModification.ReplaceNode(call, scopedCall, call.parent)
+                if(scopedArgs.any()) {
+                    val scopedCall = BuiltinFunctionCall(scopedName, scopedArgs.toMutableList(), call.position)
+                    modifications += IAstModification.ReplaceNode(call, scopedCall, call.parent)
+                }
             }
         }
 
@@ -155,8 +176,10 @@ class Inliner(private val program: Program, private val options: CompilationOpti
             call.target.targetSubroutine(program)?.let { sub ->
                 val scopedName = IdentifierReference(sub.scopedName, call.target.position)
                 val scopedArgs = makeScopedArgs(call.args)
-                val scopedCall = FunctionCallExpression(scopedName, scopedArgs.toMutableList(), call.position)
-                modifications += IAstModification.ReplaceNode(call, scopedCall, call.parent)
+                if(scopedArgs.any()) {
+                    val scopedCall = FunctionCallExpression(scopedName, scopedArgs.toMutableList(), call.position)
+                    modifications += IAstModification.ReplaceNode(call, scopedCall, call.parent)
+                }
             }
         }
 
@@ -165,7 +188,8 @@ class Inliner(private val program: Program, private val options: CompilationOpti
                 when (it) {
                     is NumericLiteral -> it.copy()
                     is IdentifierReference -> {
-                        val scoped = (it.targetStatement(program)!! as INamedStatement).scopedName
+                        val target = it.targetStatement(program) ?: return emptyList()
+                        val scoped = (target as INamedStatement).scopedName
                         IdentifierReference(scoped, it.position)
                     }
                     else -> throw InternalCompilerException("expected only number or identifier arg, otherwise too complex")

codeOptimizers/src/prog8/optimizer/StatementOptimizer.kt

@@ -30,7 +30,7 @@ class StatementOptimizer(private val program: Program,
         if(functionCallStatement.target.nameInSource==listOf("txt", "print")) {
             val arg = functionCallStatement.args.single()
             val stringVar: IdentifierReference? = if(arg is AddressOf) {
-                arg.identifier
+                if(arg.arrayIndex==null) arg.identifier else null
             } else {
                 arg as? IdentifierReference
             }
@@ -45,11 +45,7 @@ class StatementOptimizer(private val program: Program,
                             mutableListOf(NumericLiteral(DataType.UBYTE, firstCharEncoded.toDouble(), pos)),
                             functionCallStatement.void, pos
                         )
-                        val stringDecl = string.parent as VarDecl
-                        return listOf(
-                            IAstModification.ReplaceNode(functionCallStatement, chrout, parent),
-                            IAstModification.Remove(stringDecl, stringDecl.parent as IStatementContainer)
-                        )
+                        return listOf(IAstModification.ReplaceNode(functionCallStatement, chrout, parent))
                     } else if (string.value.length == 2) {
                         val firstTwoCharsEncoded = options.compTarget.encodeString(string.value.take(2), string.encoding)
                         val chrout1 = FunctionCallStatement(
@@ -62,11 +58,9 @@ class StatementOptimizer(private val program: Program,
                             mutableListOf(NumericLiteral(DataType.UBYTE, firstTwoCharsEncoded[1].toDouble(), pos)),
                             functionCallStatement.void, pos
                         )
-                        val stringDecl = string.parent as VarDecl
                         return listOf(
                             IAstModification.InsertBefore(functionCallStatement, chrout1, parent as IStatementContainer),
-                            IAstModification.ReplaceNode(functionCallStatement, chrout2, parent),
-                            IAstModification.Remove(stringDecl, stringDecl.parent as IStatementContainer)
+                            IAstModification.ReplaceNode(functionCallStatement, chrout2, parent)
                         )
                     }
                 }
@@ -77,6 +71,11 @@ class StatementOptimizer(private val program: Program,
     }
 
     override fun after(ifElse: IfElse, parent: Node): Iterable<IAstModification> {
+        val constvalue = ifElse.condition.constValue(program)
+        if(constvalue!=null) {
+            errors.warn("condition is always ${constvalue.asBooleanValue}", ifElse.condition.position)
+        }
+
         // remove empty if statements
         if(ifElse.truepart.isEmpty() && ifElse.elsepart.isEmpty())
             return listOf(IAstModification.Remove(ifElse, parent as IStatementContainer))
@@ -93,17 +92,12 @@ class StatementOptimizer(private val program: Program,
             )
         }
 
-        val constvalue = ifElse.condition.constValue(program)
         if(constvalue!=null) {
             return if(constvalue.asBooleanValue){
                 // always true -> keep only if-part
-                if(!ifElse.definingModule.isLibrary)
-                    errors.warn("condition is always true", ifElse.condition.position)
                 listOf(IAstModification.ReplaceNode(ifElse, ifElse.truepart, parent))
             } else {
                 // always false -> keep only else-part
-                if(!ifElse.definingModule.isLibrary)
-                    errors.warn("condition is always false", ifElse.condition.position)
                 listOf(IAstModification.ReplaceNode(ifElse, ifElse.elsepart, parent))
             }
         }
@@ -111,8 +105,6 @@ class StatementOptimizer(private val program: Program,
         // remove obvious dangling elses (else after a return)
         if(ifElse.elsepart.isNotEmpty() && ifElse.truepart.statements.singleOrNull() is Return) {
             val elsePart = AnonymousScope(ifElse.elsepart.statements, ifElse.elsepart.position)
-            if(options.slowCodegenWarnings)
-                errors.warn("else can be omitted", ifElse.elsepart.position)
             return listOf(
                 IAstModification.ReplaceNode(ifElse.elsepart, AnonymousScope(mutableListOf(), ifElse.elsepart.position), ifElse),
                 IAstModification.InsertAfter(ifElse, elsePart, parent as IStatementContainer)
@@ -176,6 +168,70 @@ class StatementOptimizer(private val program: Program,
             }
         }
 
+        val loopvarDt = forLoop.loopVarDt(program)
+        if(loopvarDt.istype(DataType.UWORD) || loopvarDt.istype(DataType.UBYTE)) {
+            if (range != null && range.from.constValue(program)?.number == 0.0 && range.step.constValue(program)?.number==1.0) {
+                val toBinExpr = range.to as? BinaryExpression
+                if(toBinExpr!=null && toBinExpr.operator=="-" && toBinExpr.right.constValue(program)?.number==1.0) {
+                    // FOR var IN 0 TO X-1 .... ---> var=0, DO {... , var++} UNTIL var==X
+                    val pos = forLoop.position
+                    val condition = BinaryExpression(forLoop.loopVar.copy(), "==", toBinExpr.left, pos)
+                    val incOne = PostIncrDecr(AssignTarget(forLoop.loopVar.copy(), null, null, pos), "++", pos)
+                    forLoop.body.statements.add(incOne)
+                    val replacement = AnonymousScope(mutableListOf(
+                        Assignment(AssignTarget(forLoop.loopVar.copy(), null, null, pos),
+                            NumericLiteral.optimalNumeric(0.0, pos),
+                            AssignmentOrigin.OPTIMIZER, pos),
+                        UntilLoop(forLoop.body, condition, pos)
+                    ), pos)
+                    return listOf(IAstModification.ReplaceNode(forLoop, replacement, parent))
+                }
+
+                if(options.compTarget.name!=VMTarget.NAME) {
+                    // this optimization is not effective for the VM target.
+                    val toConst = range.to.constValue(program)
+                    if (toConst == null) {
+                        // FOR var in 0 TO X ... --->  var=0, REPEAT { ... , IF var==X break , var++ }
+                        val pos = forLoop.position
+                        val incOne = PostIncrDecr(AssignTarget(forLoop.loopVar.copy(), null, null, pos), "++", pos)
+                        val breakCondition = IfElse(
+                            BinaryExpression(forLoop.loopVar, "==", range.to, pos),
+                            AnonymousScope(mutableListOf(Break(pos)), pos),
+                            AnonymousScope(mutableListOf(), pos),
+                            pos
+                        )
+                        forLoop.body.statements.add(breakCondition)
+                        forLoop.body.statements.add(incOne)
+                        val replacement = AnonymousScope(mutableListOf(
+                            Assignment(AssignTarget(forLoop.loopVar.copy(), null, null, pos),
+                                NumericLiteral.optimalNumeric(0.0, pos),
+                                AssignmentOrigin.OPTIMIZER, pos),
+                            RepeatLoop(null, forLoop.body, pos)
+                        ), pos)
+                        return listOf(IAstModification.ReplaceNode(forLoop, replacement, parent))
+                    }
+                }
+            }
+
+            if (range != null && range.to.constValue(program)?.number == 0.0 && range.step.constValue(program)?.number==-1.0) {
+                val fromExpr = range.from
+                if(fromExpr.constValue(program)==null) {
+                    // FOR X = something DOWNTO 0 {...} -->  X=something,  DO { ... , X-- } UNTIL X=255 (or 65535 if uword)
+                    val pos = forLoop.position
+                    val checkValue = NumericLiteral(loopvarDt.getOr(DataType.UNDEFINED), if(loopvarDt.istype(DataType.UBYTE)) 255.0 else 65535.0, pos)
+                    val condition = BinaryExpression(forLoop.loopVar.copy(), "==", checkValue, pos)
+                    val decOne = PostIncrDecr(AssignTarget(forLoop.loopVar.copy(), null, null, pos), "--", pos)
+                    forLoop.body.statements.add(decOne)
+                    val replacement = AnonymousScope(mutableListOf(
+                        Assignment(AssignTarget(forLoop.loopVar.copy(), null, null, pos),
+                            fromExpr, AssignmentOrigin.OPTIMIZER, pos),
+                        UntilLoop(forLoop.body, condition, pos)
+                    ), pos)
+                    return listOf(IAstModification.ReplaceNode(forLoop, replacement, parent))
+                }
+            }
+        }
+
         return noModifications
     }
 
@@ -386,7 +442,8 @@ class StatementOptimizer(private val program: Program,
     }
 
     override fun before(unrollLoop: UnrollLoop, parent: Node): Iterable<IAstModification> {
-        return if(unrollLoop.iterations<1)
+        val iterations = unrollLoop.iterations.constValue(program)?.number?.toInt()
+        return if(iterations!=null && iterations<1)
             listOf(IAstModification.Remove(unrollLoop, parent as IStatementContainer))
         else
             noModifications
@@ -431,6 +488,27 @@ class StatementOptimizer(private val program: Program,
                 }
             }
         }
+
+        val constantValue = whenStmt.condition.constValue(program)?.number
+        if(constantValue!=null) {
+            // when condition is a constant
+            var matchingChoice: WhenChoice? = null
+            loop@ for(choice in whenStmt.choices) {
+                for(value in choice.values ?: emptyList()) {
+                    if(value.constValue(program)?.number == constantValue) {
+                        matchingChoice = choice
+                        break@loop
+                    }
+                }
+            }
+            if(matchingChoice==null)
+                matchingChoice = whenStmt.choices.singleOrNull { it.values==null }
+            if(matchingChoice!=null) {
+                // get rid of the whole when-statement and just leave the matching choice
+                return listOf(IAstModification.ReplaceNode(whenStmt, matchingChoice.statements, parent))
+            }
+        }
+
         return noModifications
     }
 

codeOptimizers/src/prog8/optimizer/UnusedCodeRemover.kt

@@ -99,7 +99,7 @@ class UnusedCodeRemover(private val program: Program,
                     }
                     return removals
                 }
-                if(!subroutine.definingModule.isLibrary && !subroutine.hasBeenInlined) {
+                if(!subroutine.hasBeenInlined && subroutine.definingModule===program.toplevelModule) {
                     errors.warn("unused subroutine '${subroutine.name}'", subroutine.position)
                 }
                 if(!subroutine.inline) {
@@ -139,13 +139,20 @@ class UnusedCodeRemover(private val program: Program,
                                     )
                                 } else if(assignment.value is IFunctionCall) {
                                     // replace the unused variable's initializer function call by a void
-                                    errors.warn("replaced unused variable '${decl.name}' with void call, maybe this can be removed altogether", decl.position)
-                                    val fcall = assignment.value as IFunctionCall
-                                    val voidCall = FunctionCallStatement(fcall.target, fcall.args, true, fcall.position)
-                                    return listOf(
-                                        IAstModification.ReplaceNode(decl, voidCall, parent),
-                                        IAstModification.Remove(assignment, assignment.parent as IStatementContainer)
-                                    )
+                                    // but only if the vardecl immediately precedes it!
+                                    if(singleUse.parent.parent === parent) {
+                                        val declIndex = (parent as IStatementContainer).statements.indexOf(decl)
+                                        val singleUseIndex = (parent as IStatementContainer).statements.indexOf(singleUse.parent)
+                                        if(declIndex==singleUseIndex-1) {
+                                            errors.warn("replaced unused variable '${decl.name}' with void call, maybe this can be removed altogether", decl.position)
+                                            val fcall = assignment.value as IFunctionCall
+                                            val voidCall = FunctionCallStatement(fcall.target, fcall.args, true, fcall.position)
+                                            return listOf(
+                                                IAstModification.ReplaceNode(decl, voidCall, parent),
+                                                IAstModification.Remove(assignment, assignment.parent as IStatementContainer)
+                                            )
+                                        }
+                                    }
                                 } else {
                                     errors.warn("variable '${decl.name}' is unused but has non-trivial initialization assignment. Leaving this in but maybe it can be removed altogether", decl.position)
                                 }

compiler/build.gradle

@@ -33,14 +33,14 @@ dependencies {
     implementation project(':codeGenIntermediate')
     implementation project(':codeGenExperimental')
     implementation project(':virtualmachine')
-    implementation "org.antlr:antlr4-runtime:4.13.0"
+    implementation "org.antlr:antlr4-runtime:4.13.1"
     implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8"
     // implementation "org.jetbrains.kotlin:kotlin-reflect"
-    implementation 'org.jetbrains.kotlinx:kotlinx-cli:0.3.5'
+    implementation 'org.jetbrains.kotlinx:kotlinx-cli:0.3.6'
     implementation "com.michael-bull.kotlin-result:kotlin-result-jvm:1.1.18"
 
     testImplementation project(':intermediate')
-    testImplementation 'io.kotest:kotest-runner-junit5-jvm:5.6.2'
+    testImplementation 'io.kotest:kotest-runner-junit5-jvm:5.8.0'
 }
 
 configurations.all {
@@ -59,10 +59,10 @@ configurations {
 sourceSets {
     main {
         java {
-            srcDirs = ["${project.projectDir}/src"]
+            srcDir "${project.projectDir}/src"
         }
         resources {
-            srcDirs = ["${project.projectDir}/res"]
+            srcDir "${project.projectDir}/res"
         }
     }
     test {

compiler/res/prog8lib/atari/syslib.p8

@@ -8,6 +8,13 @@ atari {
         &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
 
+        &uword COLCRS = 85
+        &ubyte ROWCRS = 84
+
+    romsub $F24A = getchar() -> ubyte @A
+    romsub $F2B0 = outchar(ubyte character @ A)
+    romsub $F2FD = waitkey() -> ubyte @A
+
 }
 
 sys {
@@ -198,6 +205,54 @@ _longcopy
         }}
     }
 
+    sub disable_caseswitch() {
+        ; no-op
+    }
+
+    sub enable_caseswitch() {
+        ; no-op
+    }
+
+    asmsub save_prog8_internals() {
+        %asm {{
+            lda  P8ZP_SCRATCH_B1
+            sta  save_SCRATCH_ZPB1
+            lda  P8ZP_SCRATCH_REG
+            sta  save_SCRATCH_ZPREG
+            lda  P8ZP_SCRATCH_W1
+            sta  save_SCRATCH_ZPWORD1
+            lda  P8ZP_SCRATCH_W1+1
+            sta  save_SCRATCH_ZPWORD1+1
+            lda  P8ZP_SCRATCH_W2
+            sta  save_SCRATCH_ZPWORD2
+            lda  P8ZP_SCRATCH_W2+1
+            sta  save_SCRATCH_ZPWORD2+1
+            rts
+save_SCRATCH_ZPB1	.byte  0
+save_SCRATCH_ZPREG	.byte  0
+save_SCRATCH_ZPWORD1	.word  0
+save_SCRATCH_ZPWORD2	.word  0
+        }}
+    }
+
+    asmsub restore_prog8_internals() {
+        %asm {{
+            lda  save_prog8_internals.save_SCRATCH_ZPB1
+            sta  P8ZP_SCRATCH_B1
+            lda  save_prog8_internals.save_SCRATCH_ZPREG
+            sta  P8ZP_SCRATCH_REG
+            lda  save_prog8_internals.save_SCRATCH_ZPWORD1
+            sta  P8ZP_SCRATCH_W1
+            lda  save_prog8_internals.save_SCRATCH_ZPWORD1+1
+            sta  P8ZP_SCRATCH_W1+1
+            lda  save_prog8_internals.save_SCRATCH_ZPWORD2
+            sta  P8ZP_SCRATCH_W2
+            lda  save_prog8_internals.save_SCRATCH_ZPWORD2+1
+            sta  P8ZP_SCRATCH_W2+1
+            rts
+        }}
+    }
+
     inline asmsub exit(ubyte returnvalue @A) {
         ; -- immediately exit the program with a return code in the A register
         ;    TODO

compiler/res/prog8lib/atari/textio.p8

@@ -1,4 +1,5 @@
 ; Prog8 definitions for the Text I/O and Screen routines for the Atari 800XL
+; Reference:  https://www.atariarchives.org/mapping/appendix12.php
 
 %import syslib
 %import conv
@@ -24,15 +25,25 @@ sub spc() {
     txt.chrout(' ')
 }
 
-asmsub column(ubyte col @A) clobbers(A, X, Y) {
+sub column(ubyte col) {
     ; ---- set the cursor on the given column (starting with 0) on the current line
-    ;      TODO
-    %asm {{
-        rts
-    }}
+    atari.COLCRS = col
 }
 
-asmsub  fill_screen (ubyte char @ A, ubyte color @ Y) clobbers(A)  {
+sub get_column() -> ubyte {
+    return atari.COLCRS as ubyte
+}
+
+sub row(ubyte rownum) {
+    ; ---- set the cursor on the given row (starting with 0) on the current line
+    atari.ROWCRS = rownum
+}
+
+sub get_row() -> ubyte {
+    return atari.ROWCRS
+}
+
+asmsub  fill_screen (ubyte character @ A, ubyte color @ Y) clobbers(A)  {
     ; ---- fill the character screen with the given fill character and character color.
     ;      (assumes screen and color matrix are at their default addresses)
     ;      TODO
@@ -42,7 +53,7 @@ asmsub  fill_screen (ubyte char @ A, ubyte color @ Y) clobbers(A)  {
     }}
 }
 
-asmsub  clear_screenchars (ubyte char @ A) clobbers(Y)  {
+asmsub  clear_screenchars (ubyte character @ A) clobbers(Y)  {
 	; ---- clear the character screen with the given fill character (leaves colors)
 	;      (assumes screen matrix is at the default address)
 	; TODO
@@ -114,10 +125,7 @@ asmsub  scroll_down  (bool alsocolors @ Pc) clobbers(A)  {
 }
 
 
-romsub $F2B0 = outchar(ubyte char @ A)
-romsub $F2Fd = waitkey()
-
-asmsub chrout(ubyte char @ A) {
+asmsub chrout(ubyte character @ A) {
 	%asm {{
 		sta  _tmp_outchar+1
 		txa
@@ -126,7 +134,7 @@ asmsub chrout(ubyte char @ A) {
 		pha
 _tmp_outchar
 		lda  #0
-		jsr  outchar
+		jsr  atari.outchar
 		pla
 		tay
 		pla
@@ -153,10 +161,9 @@ asmsub  print (str text @ AY) clobbers(A,Y)  {
 	}}
 }
 
-asmsub  print_ub0  (ubyte value @ A) clobbers(A,Y)  {
+asmsub  print_ub0  (ubyte value @ A) clobbers(A,X,Y)  {
 	; ---- print the ubyte in A in decimal form, with left padding 0s (3 positions total)
 	%asm {{
-		stx  P8ZP_SCRATCH_REG
 		jsr  conv.ubyte2decimal
 		pha
 		tya
@@ -164,16 +171,13 @@ asmsub  print_ub0  (ubyte value @ A) clobbers(A,Y)  {
 		pla
 		jsr  chrout
 		txa
-		jsr  chrout
-		ldx  P8ZP_SCRATCH_REG
-		rts
+		jmp  chrout
 	}}
 }
 
-asmsub  print_ub  (ubyte value @ A) clobbers(A,Y)  {
+asmsub  print_ub  (ubyte value @ A) clobbers(A,X,Y)  {
 	; ---- print the ubyte in A in decimal form, without left padding 0s
 	%asm {{
-		stx  P8ZP_SCRATCH_REG
 		jsr  conv.ubyte2decimal
 _print_byte_digits
 		pha
@@ -189,16 +193,13 @@ _print_byte_digits
         beq  _ones
         jsr  chrout
 _ones   txa
-		jsr  chrout
-		ldx  P8ZP_SCRATCH_REG
-		rts
+		jmp  chrout
 	}}
 }
 
-asmsub  print_b  (byte value @ A) clobbers(A,Y)  {
+asmsub  print_b  (byte value @ A) clobbers(A,X,Y)  {
 	; ---- print the byte in A in decimal form, without left padding 0s
 	%asm {{
-		stx  P8ZP_SCRATCH_REG
 		pha
 		cmp  #0
 		bpl  +
@@ -210,10 +211,9 @@ asmsub  print_b  (byte value @ A) clobbers(A,Y)  {
 	}}
 }
 
-asmsub  print_ubhex  (ubyte value @ A, bool prefix @ Pc) clobbers(A,Y)  {
+asmsub  print_ubhex  (ubyte value @ A, bool prefix @ Pc) clobbers(A,X,Y)  {
 	; ---- print the ubyte in A in hex form (if Carry is set, a radix prefix '$' is printed as well)
 	%asm {{
-		stx  P8ZP_SCRATCH_REG
 		bcc  +
 		pha
 		lda  #'$'
@@ -222,16 +222,13 @@ asmsub  print_ubhex  (ubyte value @ A, bool prefix @ Pc) clobbers(A,Y)  {
 +		jsr  conv.ubyte2hex
 		jsr  chrout
 		tya
-		jsr  chrout
-		ldx  P8ZP_SCRATCH_REG
-		rts
+		jmp  chrout
 	}}
 }
 
-asmsub  print_ubbin  (ubyte value @ A, bool prefix @ Pc) clobbers(A,Y)  {
+asmsub  print_ubbin  (ubyte value @ A, bool prefix @ Pc) clobbers(A,X,Y)  {
 	; ---- print the ubyte in A in binary form (if Carry is set, a radix prefix '%' is printed as well)
 	%asm {{
-		stx  P8ZP_SCRATCH_REG
 		sta  P8ZP_SCRATCH_B1
 		bcc  +
 		lda  #'%'
@@ -244,12 +241,11 @@ asmsub  print_ubbin  (ubyte value @ A, bool prefix @ Pc) clobbers(A,Y)  {
 +		jsr  chrout
 		dey
 		bne  -
-		ldx  P8ZP_SCRATCH_REG
 		rts
 	}}
 }
 
-asmsub  print_uwbin  (uword value @ AY, bool prefix @ Pc) clobbers(A,Y)  {
+asmsub  print_uwbin  (uword value @ AY, bool prefix @ Pc) clobbers(A,X,Y)  {
 	; ---- print the uword in A/Y in binary form (if Carry is set, a radix prefix '%' is printed as well)
 	%asm {{
 		pha
@@ -261,7 +257,7 @@ asmsub  print_uwbin  (uword value @ AY, bool prefix @ Pc) clobbers(A,Y)  {
 	}}
 }
 
-asmsub  print_uwhex  (uword value @ AY, bool prefix @ Pc) clobbers(A,Y)  {
+asmsub  print_uwhex  (uword value @ AY, bool prefix @ Pc) clobbers(A,X,Y)  {
 	; ---- print the uword in A/Y in hexadecimal form (4 digits)
 	;      (if Carry is set, a radix prefix '$' is printed as well)
 	%asm {{
@@ -274,10 +270,9 @@ asmsub  print_uwhex  (uword value @ AY, bool prefix @ Pc) clobbers(A,Y)  {
 	}}
 }
 
-asmsub  print_uw0  (uword value @ AY) clobbers(A,Y)  {
+asmsub  print_uw0  (uword value @ AY) clobbers(A,X,Y)  {
 	; ---- print the uword in A/Y in decimal form, with left padding 0s (5 positions total)
 	%asm {{
-	    stx  P8ZP_SCRATCH_REG
 		jsr  conv.uword2decimal
 		ldy  #0
 -		lda  conv.uword2decimal.decTenThousands,y
@@ -285,17 +280,14 @@ asmsub  print_uw0  (uword value @ AY) clobbers(A,Y)  {
 		jsr  chrout
 		iny
 		bne  -
-+		ldx  P8ZP_SCRATCH_REG
-		rts
++		rts
 	}}
 }
 
-asmsub  print_uw  (uword value @ AY) clobbers(A,Y)  {
+asmsub  print_uw  (uword value @ AY) clobbers(A,X,Y)  {
 	; ---- print the uword in A/Y in decimal form, without left padding 0s
 	%asm {{
-	    stx  P8ZP_SCRATCH_REG
 		jsr  conv.uword2decimal
-		ldx  P8ZP_SCRATCH_REG
 		ldy  #0
 -		lda  conv.uword2decimal.decTenThousands,y
 		beq  _allzero
@@ -316,7 +308,7 @@ _allzero
 	}}
 }
 
-asmsub  print_w  (word value @ AY) clobbers(A,Y)  {
+asmsub  print_w  (word value @ AY) clobbers(A,X,Y)  {
 	; ---- print the (signed) word in A/Y in decimal form, without left padding 0's
 	%asm {{
 		cpy  #0
@@ -380,7 +372,7 @@ asmsub  getclr  (ubyte col @A, ubyte row @Y) clobbers(Y) -> ubyte @ A {
         }}
 }
 
-sub  setcc  (ubyte column, ubyte row, ubyte char, ubyte charcolor)  {
+sub  setcc  (ubyte col, ubyte row, ubyte char, ubyte charcolor)  {
 	; ---- set char+color at the given position on the screen
 	; TODO
 	%asm {{
@@ -388,12 +380,20 @@ sub  setcc  (ubyte column, ubyte row, ubyte char, ubyte charcolor)  {
         }}
 }
 
-asmsub  plot  (ubyte col @ Y, ubyte row @ A) clobbers(A) {
-	; ---- set cursor at specific position
-	; TODO
-	%asm  {{
-	    rts
-	}}
+sub  plot(ubyte col, ubyte rownum) {
+    column(col)
+    row(rownum)
+}
+
+sub get_cursor(uword colptr, uword rowptr) {
+    @(colptr) = get_column()
+    @(rowptr) = get_row()
+}
+
+asmsub waitkey() -> ubyte @A {
+    %asm {{
+        jmp  atari.waitkey
+    }}
 }
 
 asmsub width() clobbers(X,Y) -> ubyte @A {

compiler/res/prog8lib/c128/graphics.p8

@@ -1,62 +0,0 @@
-%import syslib
-%import textio
-
-; Bitmap pixel graphics module for the Commodore 128
-
-; TODO c128 actually implement the graphics routines. Ideally a way to 'borrow' the code form the C64 version without just copy-pasting that here?
-
-graphics {
-    %option no_symbol_prefixing
-
-    const uword WIDTH = 320
-    const ubyte HEIGHT = 200
-
-    sub enable_bitmap_mode() {
-        ; enable bitmap screen, erase it and set colors to black/white.
-        ; TODO
-    }
-
-    sub disable_bitmap_mode() {
-        ; enables text mode, erase the text screen, color white
-        ; TODO
-    }
-
-
-    sub clear_screen(ubyte pixelcolor, ubyte bgcolor) {
-        ; TODO
-    }
-
-    sub line(uword @zp x1, ubyte @zp y1, uword @zp x2, ubyte @zp y2) {
-        ; TODO
-    }
-
-    sub fillrect(uword x, uword y, uword width, uword height) {
-        ; TODO
-    }
-
-    sub rect(uword x, uword y, uword width, uword height) {
-        ; TODO
-    }
-
-    sub horizontal_line(uword x, uword y, uword length) {
-        ; TODO
-    }
-
-    sub vertical_line(uword x, uword y, uword height) {
-        ; TODO
-    }
-
-    sub circle(uword xcenter, ubyte ycenter, ubyte radius) {
-        ; TODO
-    }
-
-    sub disc(uword xcenter, ubyte ycenter, ubyte radius) {
-        ; TODO
-    }
-
-    inline asmsub  plot(uword plotx @R0, uword ploty @R1) clobbers(A, X, Y) {
-        %asm {{
-            nop     ; TODO
-        }}
-    }
-}

compiler/res/prog8lib/c128/syslib.p8

@@ -87,7 +87,7 @@ romsub $FFC6 = CHKIN(ubyte logical @ X) clobbers(A,X) -> bool @Pc    ; (via 798
 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(X, 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 $FFD2 = CHROUT(ubyte character @ A)                           ; (via 806 ($326)) output a character
 romsub $FFD5 = LOAD(ubyte verify @ A, uword address @ XY) -> bool @Pc, ubyte @ A, uword @ XY     ; (via 816 ($330)) load from device
 romsub $FFD8 = SAVE(ubyte zp_startaddr @ A, uword endaddr @ XY) -> bool @ 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
@@ -104,34 +104,26 @@ romsub $FFF3 = IOBASE() -> uword @ XY                           ; read base addr
 
 ; ---- utilities -----
 
-asmsub STOP2() -> ubyte @A  {
+asmsub STOP2() clobbers(X) -> ubyte @A  {
     ; -- check if STOP key was pressed, returns true if so.  More convenient to use than STOP() because that only sets the carry status flag.
     %asm {{
-        txa
-        pha
         jsr  cbm.STOP
         beq  +
-        pla
-        tax
         lda  #0
         rts
-+       pla
-        tax
-        lda  #1
++       lda  #1
         rts
     }}
 }
 
-asmsub RDTIM16() -> uword @AY {
+asmsub RDTIM16() clobbers(X) -> uword @AY {
     ; --  like RDTIM() but only returning the lower 16 bits in AY for convenience
     %asm {{
-        stx  P8ZP_SCRATCH_REG
         jsr  cbm.RDTIM
         pha
         txa
         tay
         pla
-        ldx  P8ZP_SCRATCH_REG
         rts
     }}
 }
@@ -343,7 +335,7 @@ asmsub  init_system()  {
     ; This means that the BASIC, KERNAL and CHARGEN ROMs are banked in,
     ; the VIC, SID and CIA chips are reset, screen is cleared, and the default IRQ is set.
     ; Also a different color scheme is chosen to identify ourselves a little.
-    ; Uppercase charset is activated, and all three registers set to 0, status flags cleared.
+    ; Uppercase charset is activated.
     %asm {{
         sei
         cld
@@ -399,81 +391,78 @@ asmsub  enable_runstop_and_charsetswitch() clobbers(A) {
     }}
 }
 
-asmsub  set_irq(uword handler @AY, bool useKernal @Pc) clobbers(A)  {
+    asmsub save_prog8_internals() {
+        %asm {{
+            lda  P8ZP_SCRATCH_B1
+            sta  save_SCRATCH_ZPB1
+            lda  P8ZP_SCRATCH_REG
+            sta  save_SCRATCH_ZPREG
+            lda  P8ZP_SCRATCH_W1
+            sta  save_SCRATCH_ZPWORD1
+            lda  P8ZP_SCRATCH_W1+1
+            sta  save_SCRATCH_ZPWORD1+1
+            lda  P8ZP_SCRATCH_W2
+            sta  save_SCRATCH_ZPWORD2
+            lda  P8ZP_SCRATCH_W2+1
+            sta  save_SCRATCH_ZPWORD2+1
+            rts
+save_SCRATCH_ZPB1	.byte  0
+save_SCRATCH_ZPREG	.byte  0
+save_SCRATCH_ZPWORD1	.word  0
+save_SCRATCH_ZPWORD2	.word  0
+        }}
+    }
+
+    asmsub restore_prog8_internals() {
+        %asm {{
+            lda  save_prog8_internals.save_SCRATCH_ZPB1
+            sta  P8ZP_SCRATCH_B1
+            lda  save_prog8_internals.save_SCRATCH_ZPREG
+            sta  P8ZP_SCRATCH_REG
+            lda  save_prog8_internals.save_SCRATCH_ZPWORD1
+            sta  P8ZP_SCRATCH_W1
+            lda  save_prog8_internals.save_SCRATCH_ZPWORD1+1
+            sta  P8ZP_SCRATCH_W1+1
+            lda  save_prog8_internals.save_SCRATCH_ZPWORD2
+            sta  P8ZP_SCRATCH_W2
+            lda  save_prog8_internals.save_SCRATCH_ZPWORD2+1
+            sta  P8ZP_SCRATCH_W2+1
+            rts
+        }}
+    }
+
+asmsub  set_irq(uword handler @AY) clobbers(A)  {
 	%asm {{
-	        sta  _modified+1
-	        sty  _modified+2
-	        lda  #0
-	        rol  a
-	        sta  _use_kernal
 		sei
+        sta  _modified+1
+        sty  _modified+2
 		lda  #<_irq_handler
 		sta  cbm.CINV
 		lda  #>_irq_handler
 		sta  cbm.CINV+1
 		cli
 		rts
-_irq_handler    jsr  _irq_handler_init
-_modified	jsr  $ffff                      ; modified
-		jsr  _irq_handler_end
-		lda  _use_kernal
-		bne  +
-		lda  #$ff
+_irq_handler
+        jsr  sys.save_prog8_internals
+        cld
+_modified
+        jsr  $ffff                      ; modified
+        pha
+        jsr  sys.restore_prog8_internals
+        pla
+        beq  +
+		jmp  cbm.IRQDFRT		; continue with normal kernal irq routine
++		lda  #$ff
 		sta  c64.VICIRQ			; acknowledge raster irq
 		lda  c64.CIA1ICR		; acknowledge CIA1 interrupt
-		; end irq processing - don't use kernal's irq handling
 		pla
 		tay
 		pla
 		tax
 		pla
 		rti
-+		jmp  cbm.IRQDFRT		; continue with normal kernal irq routine
 
 _use_kernal     .byte  0
-
-_irq_handler_init
-		; save all zp scratch registers as these might be clobbered by the irq routine
-		lda  P8ZP_SCRATCH_B1
-		sta  IRQ_SCRATCH_ZPB1
-		lda  P8ZP_SCRATCH_REG
-		sta  IRQ_SCRATCH_ZPREG
-		lda  P8ZP_SCRATCH_W1
-		sta  IRQ_SCRATCH_ZPWORD1
-		lda  P8ZP_SCRATCH_W1+1
-		sta  IRQ_SCRATCH_ZPWORD1+1
-		lda  P8ZP_SCRATCH_W2
-		sta  IRQ_SCRATCH_ZPWORD2
-		lda  P8ZP_SCRATCH_W2+1
-		sta  IRQ_SCRATCH_ZPWORD2+1
-		; Set X to the bottom 32 bytes of the evaluation stack, to HOPEFULLY not clobber it.
-		; This leaves 128-32=96 stack entries for the main program, and 32 stack entries for the IRQ handler.
-		; We assume IRQ handlers don't contain complex expressions taking up more than that.
-		ldx  #32
-		cld
-		rts
-
-_irq_handler_end
-		; restore all zp scratch registers
-		lda  IRQ_SCRATCH_ZPB1
-		sta  P8ZP_SCRATCH_B1
-		lda  IRQ_SCRATCH_ZPREG
-		sta  P8ZP_SCRATCH_REG
-		lda  IRQ_SCRATCH_ZPWORD1
-		sta  P8ZP_SCRATCH_W1
-		lda  IRQ_SCRATCH_ZPWORD1+1
-		sta  P8ZP_SCRATCH_W1+1
-		lda  IRQ_SCRATCH_ZPWORD2
-		sta  P8ZP_SCRATCH_W2
-		lda  IRQ_SCRATCH_ZPWORD2+1
-		sta  P8ZP_SCRATCH_W2+1
-		rts
-
-IRQ_SCRATCH_ZPB1	.byte  0
-IRQ_SCRATCH_ZPREG	.byte  0
-IRQ_SCRATCH_ZPWORD1	.word  0
-IRQ_SCRATCH_ZPWORD2	.word  0
-
 		}}
 }
 
@@ -493,40 +482,39 @@ asmsub  restore_irq() clobbers(A) {
 	}}
 }
 
-asmsub  set_rasterirq(uword handler @AY, uword rasterpos @R0, bool useKernal @Pc) clobbers(A) {
+asmsub  set_rasterirq(uword handler @AY, uword rasterpos @R0) clobbers(A) {
 	%asm {{
-	        sta  _modified+1
-	        sty  _modified+2
-	        lda  #0
-	        rol  a
-	        sta  set_irq._use_kernal
-		lda  cx16.r0
-		ldy  cx16.r0+1
-		sei
-		jsr  _setup_raster_irq
-		lda  #<_raster_irq_handler
-		sta  cbm.CINV
-		lda  #>_raster_irq_handler
-		sta  cbm.CINV+1
-		cli
-		rts
+        sei
+        sta  _modified+1
+        sty  _modified+2
+        lda  cx16.r0
+        ldy  cx16.r0+1
+        jsr  _setup_raster_irq
+        lda  #<_raster_irq_handler
+        sta  cbm.CINV
+        lda  #>_raster_irq_handler
+        sta  cbm.CINV+1
+        cli
+        rts
 
 _raster_irq_handler
-		jsr  set_irq._irq_handler_init
-_modified	jsr  $ffff              ; modified
-		jsr  set_irq._irq_handler_end
+		jsr  sys.save_prog8_internals
+		cld
+_modified
+        jsr  $ffff              ; modified
+        pha
+		jsr  sys.restore_prog8_internals
         lda  #$ff
         sta  c64.VICIRQ			; acknowledge raster irq
-		lda  set_irq._use_kernal
-		bne  +
-		; end irq processing - don't use kernal's irq handling
 		pla
+		beq  +
+		jmp  cbm.IRQDFRT        ; continue with kernal irq routine
++		pla
 		tay
 		pla
 		tax
 		pla
 		rti
-+		jmp  cbm.IRQDFRT                ; continue with kernal irq routine
 
 _setup_raster_irq
 		pha
@@ -746,6 +734,20 @@ _longcopy
         }}
     }
 
+    inline asmsub disable_caseswitch() {
+        %asm {{
+            lda  #$80
+            sta  247
+        }}
+    }
+
+    inline asmsub enable_caseswitch() {
+        %asm {{
+            lda  #0
+            sta  247
+        }}
+    }
+
     inline asmsub exit(ubyte returnvalue @A) {
         ; -- immediately exit the program with a return code in the A register
         %asm {{
@@ -774,111 +776,108 @@ cx16 {
     ; the sixteen virtual 16-bit registers that the CX16 has defined in the zeropage
     ; they are simulated on the C128 as well but their location in memory is different
     ; (because there's no room for them in the zeropage)
-    ; $1300-$1bff is unused RAM on C128. We'll use $1a00-$1bff as the lo/hi evalstack.
-    ; the virtual registers are allocated at the bottom of the eval-stack (should be ample space unless
-    ; you're doing insane nesting of expressions...)
-    ; NOTE: the memory location of these registers can change based on the "-esa" compiler option
-    &uword r0  = $1b00
-    &uword r1  = $1b02
-    &uword r2  = $1b04
-    &uword r3  = $1b06
-    &uword r4  = $1b08
-    &uword r5  = $1b0a
-    &uword r6  = $1b0c
-    &uword r7  = $1b0e
-    &uword r8  = $1b10
-    &uword r9  = $1b12
-    &uword r10 = $1b14
-    &uword r11 = $1b16
-    &uword r12 = $1b18
-    &uword r13 = $1b1a
-    &uword r14 = $1b1c
-    &uword r15 = $1b1e
+    ; $1300-$1bff is unused RAM on C128.
+    &uword r0  = $1be0
+    &uword r1  = $1be2
+    &uword r2  = $1be4
+    &uword r3  = $1be6
+    &uword r4  = $1be8
+    &uword r5  = $1bea
+    &uword r6  = $1bec
+    &uword r7  = $1bee
+    &uword r8  = $1bf0
+    &uword r9  = $1bf2
+    &uword r10 = $1bf4
+    &uword r11 = $1bf6
+    &uword r12 = $1bf8
+    &uword r13 = $1bfa
+    &uword r14 = $1bfc
+    &uword r15 = $1bfe
 
-    &word r0s  = $1b00
-    &word r1s  = $1b02
-    &word r2s  = $1b04
-    &word r3s  = $1b06
-    &word r4s  = $1b08
-    &word r5s  = $1b0a
-    &word r6s  = $1b0c
-    &word r7s  = $1b0e
-    &word r8s  = $1b10
-    &word r9s  = $1b12
-    &word r10s = $1b14
-    &word r11s = $1b16
-    &word r12s = $1b18
-    &word r13s = $1b1a
-    &word r14s = $1b1c
-    &word r15s = $1b1e
+    &word r0s  = $1be0
+    &word r1s  = $1be2
+    &word r2s  = $1be4
+    &word r3s  = $1be6
+    &word r4s  = $1be8
+    &word r5s  = $1bea
+    &word r6s  = $1bec
+    &word r7s  = $1bee
+    &word r8s  = $1bf0
+    &word r9s  = $1bf2
+    &word r10s = $1bf4
+    &word r11s = $1bf6
+    &word r12s = $1bf8
+    &word r13s = $1bfa
+    &word r14s = $1bfc
+    &word r15s = $1bfe
 
-    &ubyte r0L  = $1b00
-    &ubyte r1L  = $1b02
-    &ubyte r2L  = $1b04
-    &ubyte r3L  = $1b06
-    &ubyte r4L  = $1b08
-    &ubyte r5L  = $1b0a
-    &ubyte r6L  = $1b0c
-    &ubyte r7L  = $1b0e
-    &ubyte r8L  = $1b10
-    &ubyte r9L  = $1b12
-    &ubyte r10L = $1b14
-    &ubyte r11L = $1b16
-    &ubyte r12L = $1b18
-    &ubyte r13L = $1b1a
-    &ubyte r14L = $1b1c
-    &ubyte r15L = $1b1e
+    &ubyte r0L  = $1be0
+    &ubyte r1L  = $1be2
+    &ubyte r2L  = $1be4
+    &ubyte r3L  = $1be6
+    &ubyte r4L  = $1be8
+    &ubyte r5L  = $1bea
+    &ubyte r6L  = $1bec
+    &ubyte r7L  = $1bee
+    &ubyte r8L  = $1bf0
+    &ubyte r9L  = $1bf2
+    &ubyte r10L = $1bf4
+    &ubyte r11L = $1bf6
+    &ubyte r12L = $1bf8
+    &ubyte r13L = $1bfa
+    &ubyte r14L = $1bfc
+    &ubyte r15L = $1bfe
 
-    &ubyte r0H  = $1b01
-    &ubyte r1H  = $1b03
-    &ubyte r2H  = $1b05
-    &ubyte r3H  = $1b07
-    &ubyte r4H  = $1b09
-    &ubyte r5H  = $1b0b
-    &ubyte r6H  = $1b0d
-    &ubyte r7H  = $1b0f
-    &ubyte r8H  = $1b11
-    &ubyte r9H  = $1b13
-    &ubyte r10H = $1b15
-    &ubyte r11H = $1b17
-    &ubyte r12H = $1b19
-    &ubyte r13H = $1b1b
-    &ubyte r14H = $1b1d
-    &ubyte r15H = $1b1f
+    &ubyte r0H  = $1be1
+    &ubyte r1H  = $1be3
+    &ubyte r2H  = $1be5
+    &ubyte r3H  = $1be7
+    &ubyte r4H  = $1be9
+    &ubyte r5H  = $1beb
+    &ubyte r6H  = $1bed
+    &ubyte r7H  = $1bef
+    &ubyte r8H  = $1bf1
+    &ubyte r9H  = $1bf3
+    &ubyte r10H = $1bf5
+    &ubyte r11H = $1bf7
+    &ubyte r12H = $1bf9
+    &ubyte r13H = $1bfb
+    &ubyte r14H = $1bfd
+    &ubyte r15H = $1bff
 
-    &byte r0sL  = $1b00
-    &byte r1sL  = $1b02
-    &byte r2sL  = $1b04
-    &byte r3sL  = $1b06
-    &byte r4sL  = $1b08
-    &byte r5sL  = $1b0a
-    &byte r6sL  = $1b0c
-    &byte r7sL  = $1b0e
-    &byte r8sL  = $1b10
-    &byte r9sL  = $1b12
-    &byte r10sL = $1b14
-    &byte r11sL = $1b16
-    &byte r12sL = $1b18
-    &byte r13sL = $1b1a
-    &byte r14sL = $1b1c
-    &byte r15sL = $1b1e
+    &byte r0sL  = $1be0
+    &byte r1sL  = $1be2
+    &byte r2sL  = $1be4
+    &byte r3sL  = $1be6
+    &byte r4sL  = $1be8
+    &byte r5sL  = $1bea
+    &byte r6sL  = $1bec
+    &byte r7sL  = $1bee
+    &byte r8sL  = $1bf0
+    &byte r9sL  = $1bf2
+    &byte r10sL = $1bf4
+    &byte r11sL = $1bf6
+    &byte r12sL = $1bf8
+    &byte r13sL = $1bfa
+    &byte r14sL = $1bfc
+    &byte r15sL = $1bfe
 
-    &byte r0sH  = $1b01
-    &byte r1sH  = $1b03
-    &byte r2sH  = $1b05
-    &byte r3sH  = $1b07
-    &byte r4sH  = $1b09
-    &byte r5sH  = $1b0b
-    &byte r6sH  = $1b0d
-    &byte r7sH  = $1b0f
-    &byte r8sH  = $1b11
-    &byte r9sH  = $1b13
-    &byte r10sH = $1b15
-    &byte r11sH = $1b17
-    &byte r12sH = $1b19
-    &byte r13sH = $1b1b
-    &byte r14sH = $1b1d
-    &byte r15sH = $1b1f
+    &byte r0sH  = $1be1
+    &byte r1sH  = $1be3
+    &byte r2sH  = $1be5
+    &byte r3sH  = $1be7
+    &byte r4sH  = $1be9
+    &byte r5sH  = $1beb
+    &byte r6sH  = $1bed
+    &byte r7sH  = $1bef
+    &byte r8sH  = $1bf1
+    &byte r9sH  = $1bf3
+    &byte r10sH = $1bf5
+    &byte r11sH = $1bf7
+    &byte r12sH = $1bf9
+    &byte r13sH = $1bfb
+    &byte r14sH = $1bfd
+    &byte r15sH = $1bff
 
     asmsub save_virtual_registers() clobbers(A,Y) {
         %asm {{

compiler/res/prog8lib/c128/textio.p8

@@ -1,4 +1,6 @@
-; Prog8 definitions for the Text I/O and Screen routines for the Commodore-64
+; Prog8 definitions for the Text I/O and Screen routines for the Commodore-128
+; All routines work with Screencode character encoding, except `print`, `chrout` and `input_chars`,
+; these work with PETSCII encoding instead.
 
 %import syslib
 %import conv
@@ -38,6 +40,45 @@ asmsub column(ubyte col @A) clobbers(A, X, Y) {
     }}
 }
 
+
+asmsub get_column() -> ubyte @Y {
+    %asm {{
+        sec
+        jmp cbm.PLOT
+    }}
+}
+
+asmsub row(ubyte rownum @A) clobbers(A, X, Y) {
+    ; ---- set the cursor on the given row (starting with 0) on the current line
+    %asm {{
+        sec
+        jsr  cbm.PLOT
+        tax
+        clc
+        jmp  cbm.PLOT
+    }}
+}
+
+asmsub get_row() -> ubyte @X {
+    %asm {{
+        sec
+        jmp cbm.PLOT
+    }}
+}
+
+sub get_cursor(uword colptr, uword rowptr) {
+    %asm {{
+        sec
+        jsr cbm.PLOT
+        tya
+        ldy #$00
+        sta (colptr),y
+        txa
+        sta (rowptr),y
+    }}
+}
+
+
 asmsub  fill_screen (ubyte char @ A, ubyte color @ Y) clobbers(A)  {
 	; ---- fill the character screen with the given fill character and character color.
 	;      (assumes screen and color matrix are at their default addresses)
@@ -97,13 +138,12 @@ sub uppercase() {
     c128.VM1 &= ~2
 }
 
-asmsub  scroll_left  (bool alsocolors @ Pc) clobbers(A, Y)  {
+asmsub  scroll_left  (bool alsocolors @ Pc) clobbers(A, X, 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  P8ZP_SCRATCH_REG
 		bcc _scroll_screen
 
 +               ; scroll the screen and the color memory
@@ -133,17 +173,15 @@ _scroll_screen  ; scroll only the screen memory
 		dey
 		bpl  -
 
-		ldx  P8ZP_SCRATCH_REG
 		rts
 	}}
 }
 
-asmsub  scroll_right  (bool alsocolors @ Pc) clobbers(A)  {
+asmsub  scroll_right  (bool alsocolors @ Pc) clobbers(A,X)  {
 	; ---- scroll the whole screen 1 character to the right
 	;      contents of the leftmost column are unchanged, you should clear/refill this yourself
 	;      Carry flag determines if screen color data must be scrolled too
 	%asm {{
-		stx  P8ZP_SCRATCH_REG
 		bcc  _scroll_screen
 
 +               ; scroll the screen and the color memory
@@ -169,17 +207,15 @@ _scroll_screen  ; scroll only the screen memory
 		dex
 		bpl  -
 
-		ldx  P8ZP_SCRATCH_REG
 		rts
 	}}
 }
 
-asmsub  scroll_up  (bool alsocolors @ Pc) clobbers(A)  {
+asmsub  scroll_up  (bool alsocolors @ Pc) clobbers(A,X)  {
 	; ---- scroll the whole screen 1 character up
 	;      contents of the bottom row are unchanged, you should refill/clear this yourself
 	;      Carry flag determines if screen color data must be scrolled too
 	%asm {{
-		stx  P8ZP_SCRATCH_REG
 		bcc  _scroll_screen
 
 +               ; scroll the screen and the color memory
@@ -205,17 +241,15 @@ _scroll_screen  ; scroll only the screen memory
 		dex
 		bpl  -
 
-		ldx  P8ZP_SCRATCH_REG
 		rts
 	}}
 }
 
-asmsub  scroll_down  (bool alsocolors @ Pc) clobbers(A)  {
+asmsub  scroll_down  (bool alsocolors @ Pc) clobbers(A,X)  {
 	; ---- scroll the whole screen 1 character down
 	;      contents of the top row are unchanged, you should refill/clear this yourself
 	;      Carry flag determines if screen color data must be scrolled too
 	%asm {{
-		stx  P8ZP_SCRATCH_REG
 		bcc  _scroll_screen
 
 +               ; scroll the screen and the color memory
@@ -241,15 +275,14 @@ _scroll_screen  ; scroll only the screen memory
 		dex
 		bpl  -
 
-		ldx  P8ZP_SCRATCH_REG
 		rts
 	}}
 }
 
-romsub $FFD2 = chrout(ubyte char @ A)    ; for consistency. You can also use cbm.CHROUT directly ofcourse.
+romsub $FFD2 = chrout(ubyte char @ A)    ; for consistency. You can also use cbm.CHROUT directly ofcourse. Note: takes a PETSCII encoded character.
 
 asmsub  print (str text @ AY) clobbers(A,Y)  {
-	; ---- print null terminated string from A/Y
+	; ---- print null terminated string, in PETSCII encoding, from A/Y
 	; note: the compiler contains an optimization that will replace
 	;       a call to this subroutine with a string argument of just one char,
 	;       by just one call to cbm.CHROUT of that single char.
@@ -266,10 +299,9 @@ asmsub  print (str text @ AY) clobbers(A,Y)  {
 	}}
 }
 
-asmsub  print_ub0  (ubyte value @ A) clobbers(A,Y)  {
+asmsub  print_ub0  (ubyte value @ A) clobbers(A,X,Y)  {
 	; ---- print the ubyte in A in decimal form, with left padding 0s (3 positions total)
 	%asm {{
-		stx  P8ZP_SCRATCH_REG
 		jsr  conv.ubyte2decimal
 		pha
 		tya
@@ -277,16 +309,13 @@ asmsub  print_ub0  (ubyte value @ A) clobbers(A,Y)  {
 		pla
 		jsr  cbm.CHROUT
 		txa
-		jsr  cbm.CHROUT
-		ldx  P8ZP_SCRATCH_REG
-		rts
+		jmp  cbm.CHROUT
 	}}
 }
 
-asmsub  print_ub  (ubyte value @ A) clobbers(A,Y)  {
+asmsub  print_ub  (ubyte value @ A) clobbers(A,X,Y)  {
 	; ---- print the ubyte in A in decimal form, without left padding 0s
 	%asm {{
-		stx  P8ZP_SCRATCH_REG
 		jsr  conv.ubyte2decimal
 _print_byte_digits
 		pha
@@ -302,16 +331,13 @@ _print_byte_digits
         beq  _ones
         jsr  cbm.CHROUT
 _ones   txa
-		jsr  cbm.CHROUT
-		ldx  P8ZP_SCRATCH_REG
-		rts
+		jmp  cbm.CHROUT
 	}}
 }
 
-asmsub  print_b  (byte value @ A) clobbers(A,Y)  {
+asmsub  print_b  (byte value @ A) clobbers(A,X,Y)  {
 	; ---- print the byte in A in decimal form, without left padding 0s
 	%asm {{
-		stx  P8ZP_SCRATCH_REG
 		pha
 		cmp  #0
 		bpl  +
@@ -323,10 +349,9 @@ asmsub  print_b  (byte value @ A) clobbers(A,Y)  {
 	}}
 }
 
-asmsub  print_ubhex  (ubyte value @ A, bool prefix @ Pc) clobbers(A,Y)  {
+asmsub  print_ubhex  (ubyte value @ A, bool prefix @ Pc) clobbers(A,X,Y)  {
 	; ---- print the ubyte in A in hex form (if Carry is set, a radix prefix '$' is printed as well)
 	%asm {{
-		stx  P8ZP_SCRATCH_REG
 		bcc  +
 		pha
 		lda  #'$'
@@ -335,16 +360,13 @@ asmsub  print_ubhex  (ubyte value @ A, bool prefix @ Pc) clobbers(A,Y)  {
 +		jsr  conv.ubyte2hex
 		jsr  cbm.CHROUT
 		tya
-		jsr  cbm.CHROUT
-		ldx  P8ZP_SCRATCH_REG
-		rts
+		jmp  cbm.CHROUT
 	}}
 }
 
-asmsub  print_ubbin  (ubyte value @ A, bool prefix @ Pc) clobbers(A,Y)  {
+asmsub  print_ubbin  (ubyte value @ A, bool prefix @ Pc) clobbers(A,X,Y)  {
 	; ---- print the ubyte in A in binary form (if Carry is set, a radix prefix '%' is printed as well)
 	%asm {{
-		stx  P8ZP_SCRATCH_REG
 		sta  P8ZP_SCRATCH_B1
 		bcc  +
 		lda  #'%'
@@ -357,12 +379,11 @@ asmsub  print_ubbin  (ubyte value @ A, bool prefix @ Pc) clobbers(A,Y)  {
 +		jsr  cbm.CHROUT
 		dey
 		bne  -
-		ldx  P8ZP_SCRATCH_REG
 		rts
 	}}
 }
 
-asmsub  print_uwbin  (uword value @ AY, bool prefix @ Pc) clobbers(A,Y)  {
+asmsub  print_uwbin  (uword value @ AY, bool prefix @ Pc) clobbers(A,X,Y)  {
 	; ---- print the uword in A/Y in binary form (if Carry is set, a radix prefix '%' is printed as well)
 	%asm {{
 		pha
@@ -374,7 +395,7 @@ asmsub  print_uwbin  (uword value @ AY, bool prefix @ Pc) clobbers(A,Y)  {
 	}}
 }
 
-asmsub  print_uwhex  (uword value @ AY, bool prefix @ Pc) clobbers(A,Y)  {
+asmsub  print_uwhex  (uword value @ AY, bool prefix @ Pc) clobbers(A,X,Y)  {
 	; ---- print the uword in A/Y in hexadecimal form (4 digits)
 	;      (if Carry is set, a radix prefix '$' is printed as well)
 	%asm {{
@@ -387,10 +408,9 @@ asmsub  print_uwhex  (uword value @ AY, bool prefix @ Pc) clobbers(A,Y)  {
 	}}
 }
 
-asmsub  print_uw0  (uword value @ AY) clobbers(A,Y)  {
+asmsub  print_uw0  (uword value @ AY) clobbers(A,X,Y)  {
 	; ---- print the uword in A/Y in decimal form, with left padding 0s (5 positions total)
 	%asm {{
-	    stx  P8ZP_SCRATCH_REG
 		jsr  conv.uword2decimal
 		ldy  #0
 -		lda  conv.uword2decimal.decTenThousands,y
@@ -398,17 +418,14 @@ asmsub  print_uw0  (uword value @ AY) clobbers(A,Y)  {
 		jsr  cbm.CHROUT
 		iny
 		bne  -
-+		ldx  P8ZP_SCRATCH_REG
-		rts
++		rts
 	}}
 }
 
-asmsub  print_uw  (uword value @ AY) clobbers(A,Y)  {
+asmsub  print_uw  (uword value @ AY) clobbers(A,X,Y)  {
 	; ---- print the uword in A/Y in decimal form, without left padding 0s
 	%asm {{
-	    stx  P8ZP_SCRATCH_REG
 		jsr  conv.uword2decimal
-		ldx  P8ZP_SCRATCH_REG
 		ldy  #0
 -		lda  conv.uword2decimal.decTenThousands,y
 		beq  _allzero
@@ -429,7 +446,7 @@ _allzero
 	}}
 }
 
-asmsub  print_w  (word value @ AY) clobbers(A,Y)  {
+asmsub  print_w  (word value @ AY) clobbers(A,X,Y)  {
 	; ---- print the (signed) word in A/Y in decimal form, without left padding 0's
 	%asm {{
 		cpy  #0
@@ -451,7 +468,8 @@ asmsub  print_w  (word value @ AY) clobbers(A,Y)  {
 }
 
 asmsub  input_chars  (uword buffer @ AY) clobbers(A) -> ubyte @ Y  {
-	; ---- Input a string (max. 80 chars) from the keyboard. Returns length in Y. (string is terminated with a 0 byte as well)
+	; ---- Input a string (max. 80 chars) from the keyboard, in PETSCII encoding.
+	;      Returns length in Y. (string is terminated with a 0 byte as well)
 	;      It assumes the keyboard is selected as I/O channel!
 
 	%asm {{
@@ -490,7 +508,7 @@ asmsub  setchr  (ubyte col @X, ubyte row @Y, ubyte character @A) clobbers(A, Y)
 _mod		sta  $ffff		; modified
 		rts
 
-_screenrows	.word  $0400 + range(0, 1000, 40)
+_screenrows	.word  cbm.Screen + range(0, 1000, 40)
 	}}
 }
 
@@ -557,7 +575,7 @@ _mod		lda  $ffff		; modified
 	}}
 }
 
-sub  setcc  (ubyte column, ubyte row, ubyte char, ubyte charcolor)  {
+sub  setcc  (ubyte col, ubyte row, ubyte character, ubyte charcolor)  {
 	; ---- set char+color at the given position on the screen
 	%asm {{
 		lda  row
@@ -569,13 +587,13 @@ sub  setcc  (ubyte column, ubyte row, ubyte char, ubyte charcolor)  {
 		sta  _colormod+2
 		lda  setchr._screenrows,y
 		clc
-		adc  column
+		adc  col
 		sta  _charmod+1
 		sta  _colormod+1
 		bcc  +
 		inc  _charmod+2
 		inc  _colormod+2
-+		lda  char
++		lda  character
 _charmod	sta  $ffff		; modified
 		lda  charcolor
 _colormod	sta  $ffff		; modified
@@ -583,15 +601,10 @@ _colormod	sta  $ffff		; modified
 	}}
 }
 
-asmsub  plot  (ubyte col @ Y, ubyte row @ A) clobbers(A) {
-	; ---- safe wrapper around PLOT kernal routine, to save the X register.
+asmsub  plot  (ubyte col @ Y, ubyte row @ X) {
 	%asm  {{
-		stx  P8ZP_SCRATCH_REG
-		tax
 		clc
-		jsr  cbm.PLOT
-		ldx  P8ZP_SCRATCH_REG
-		rts
+		jmp  cbm.PLOT
 	}}
 }
 
@@ -613,4 +626,11 @@ asmsub height() clobbers(X, Y) -> ubyte @A {
     }}
 }
 
+asmsub waitkey() -> ubyte @A {
+    %asm {{
+-       jsr cbm.GETIN
+        beq -
+        rts
+    }}
+}
 }

compiler/res/prog8lib/c64/floats.asm

@@ -5,13 +5,11 @@ FL_ZERO_const	.byte  0,0,0,0,0		; 0.0
 FL_LOG2_const	.byte  $80, $31, $72, $17, $f8	; log(2)
 
 
-floats_store_reg	.byte  0		; temp storage
 floats_temp_var         .byte  0,0,0,0,0        ; temporary storage for a float
 
 ub2float	.proc
 		; -- convert ubyte in SCRATCH_ZPB1 to float at address A/Y
-		;    clobbers A, Y
-		stx  P8ZP_SCRATCH_REG
+		;    clobbers A, X, Y
 		sta  P8ZP_SCRATCH_W2
 		sty  P8ZP_SCRATCH_W2+1
 		ldy  P8ZP_SCRATCH_B1
@@ -19,15 +17,12 @@ ub2float	.proc
 		jsr  GIVAYF
 _fac_to_mem	ldx  P8ZP_SCRATCH_W2
 		ldy  P8ZP_SCRATCH_W2+1
-		jsr  MOVMF
-		ldx  P8ZP_SCRATCH_REG
-		rts
+		jmp  MOVMF
 		.pend
 
 b2float		.proc
 		; -- convert byte in SCRATCH_ZPB1 to float at address A/Y
-		;    clobbers A, Y
-		stx  P8ZP_SCRATCH_REG
+		;    clobbers A, X, Y
 		sta  P8ZP_SCRATCH_W2
 		sty  P8ZP_SCRATCH_W2+1
 		lda  P8ZP_SCRATCH_B1
@@ -37,7 +32,7 @@ b2float		.proc
 
 uw2float	.proc
 		; -- convert uword in SCRATCH_ZPWORD1 to float at address A/Y
-		stx  P8ZP_SCRATCH_REG
+		;    clobbers X
 		sta  P8ZP_SCRATCH_W2
 		sty  P8ZP_SCRATCH_W2+1
 		lda  P8ZP_SCRATCH_W1
@@ -48,7 +43,7 @@ uw2float	.proc
 
 w2float		.proc
 		; -- convert word in SCRATCH_ZPWORD1 to float at address A/Y
-		stx  P8ZP_SCRATCH_REG
+		;    clobbers X
 		sta  P8ZP_SCRATCH_W2
 		sty  P8ZP_SCRATCH_W2+1
 		ldy  P8ZP_SCRATCH_W1
@@ -60,7 +55,7 @@ w2float		.proc
 
 cast_from_uw	.proc
 		; -- uword in A/Y into float var at (P8ZP_SCRATCH_W2)
-		stx  P8ZP_SCRATCH_REG
+		;    clobbers X
 		jsr  GIVUAYFAY
 		jmp  ub2float._fac_to_mem
 		.pend
@@ -68,7 +63,7 @@ cast_from_uw	.proc
 
 cast_from_w	.proc
 		; -- word in A/Y into float var at (P8ZP_SCRATCH_W2)
-		stx  P8ZP_SCRATCH_REG
+		;    clobbers X
 		jsr  GIVAYFAY
 		jmp  ub2float._fac_to_mem
 		.pend
@@ -76,7 +71,7 @@ cast_from_w	.proc
 
 cast_from_ub	.proc
 		; -- ubyte in Y into float var at (P8ZP_SCRATCH_W2)
-		stx  P8ZP_SCRATCH_REG
+		;    clobbers X
 		jsr  FREADUY
 		jmp  ub2float._fac_to_mem
 		.pend
@@ -84,169 +79,41 @@ cast_from_ub	.proc
 
 cast_from_b	.proc
 		; -- byte in A into float var at (P8ZP_SCRATCH_W2)
-		stx  P8ZP_SCRATCH_REG
+		;    clobbers X
 		jsr  FREADSA
 		jmp  ub2float._fac_to_mem
 		.pend
 
 cast_as_uw_into_ya	.proc               ; also used for float 2 ub
 		; -- cast float at A/Y to uword into Y/A
+		;    clobbers X
 		jsr  MOVFM
 		jmp  cast_FAC1_as_uw_into_ya
 		.pend
 
 cast_as_w_into_ay	.proc               ; also used for float 2 b
 		; -- cast float at A/Y to word into A/Y
+		;    clobbers X
 		jsr  MOVFM
 		jmp  cast_FAC1_as_w_into_ay
 		.pend
 
 cast_FAC1_as_uw_into_ya	.proc               ; also used for float 2 ub
 		; -- cast fac1 to uword into Y/A
-		stx  P8ZP_SCRATCH_REG
-		jsr  GETADR     ; into Y/A
-		ldx  P8ZP_SCRATCH_REG
-		rts
+		;    clobbers X
+		jmp  GETADR     ; into Y/A
 		.pend
 
 cast_FAC1_as_w_into_ay	.proc               ; also used for float 2 b
 		; -- cast fac1 to word into A/Y
-		stx  P8ZP_SCRATCH_REG
+		;    clobbers X
 		jsr  AYINT
 		ldy  floats.AYINT_facmo
 		lda  floats.AYINT_facmo+1
-		ldx  P8ZP_SCRATCH_REG
 		rts
 		.pend
 
 
-stack_b2float	.proc
-		; -- b2float operating on the stack
-		inx
-		lda  P8ESTACK_LO,x
-		stx  P8ZP_SCRATCH_REG
-		jsr  FREADSA
-		jmp  push_fac1._internal
-		.pend
-
-stack_w2float	.proc
-		; -- w2float operating on the stack
-		inx
-		ldy  P8ESTACK_LO,x
-		lda  P8ESTACK_HI,x
-		stx  P8ZP_SCRATCH_REG
-		jsr  GIVAYF
-		jmp  push_fac1._internal
-		.pend
-
-stack_ub2float	.proc
-		; -- ub2float operating on the stack
-		inx
-		lda  P8ESTACK_LO,x
-		stx  P8ZP_SCRATCH_REG
-		tay
-		lda  #0
-		jsr  GIVAYF
-		jmp  push_fac1._internal
-		.pend
-
-stack_uw2float	.proc
-		; -- uw2float operating on the stack
-		inx
-		lda  P8ESTACK_LO,x
-		ldy  P8ESTACK_HI,x
-		stx  P8ZP_SCRATCH_REG
-		jsr  GIVUAYFAY
-		jmp  push_fac1._internal
-		.pend
-
-stack_float2w	.proc               ; also used for float2b
-		jsr  pop_float_fac1
-		stx  P8ZP_SCRATCH_REG
-		jsr  AYINT
-		ldx  P8ZP_SCRATCH_REG
-		lda  floats.AYINT_facmo
-		sta  P8ESTACK_HI,x
-		lda  floats.AYINT_facmo+1
-		sta  P8ESTACK_LO,x
-		dex
-		rts
-		.pend
-
-stack_float2uw	.proc               ; also used for float2ub
-		jsr  pop_float_fac1
-		stx  P8ZP_SCRATCH_REG
-		jsr  GETADR
-		ldx  P8ZP_SCRATCH_REG
-		sta  P8ESTACK_HI,x
-		tya
-		sta  P8ESTACK_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  P8ZP_SCRATCH_W1
-		sty  P8ZP_SCRATCH_W1+1
-		ldy  #0
-		lda  (P8ZP_SCRATCH_W1),y
-		sta  P8ESTACK_LO,x
-		iny
-		lda  (P8ZP_SCRATCH_W1),y
-		sta  P8ESTACK_HI,x
-		dex
-		iny
-		lda  (P8ZP_SCRATCH_W1),y
-		sta  P8ESTACK_LO,x
-		iny
-		lda  (P8ZP_SCRATCH_W1),y
-		sta  P8ESTACK_HI,x
-		dex
-		iny
-		lda  (P8ZP_SCRATCH_W1),y
-		sta  P8ESTACK_LO,x
-		dex
-		rts
-		.pend
-
-pop_float	.proc
-		; ---- pops mflpt5 from stack to memory A/Y
-		; (frees 3 stack positions = 6 bytes of which 1 is padding)
-		sta  P8ZP_SCRATCH_W1
-		sty  P8ZP_SCRATCH_W1+1
-		ldy  #4
-		inx
-		lda  P8ESTACK_LO,x
-		sta  (P8ZP_SCRATCH_W1),y
-		dey
-		inx
-		lda  P8ESTACK_HI,x
-		sta  (P8ZP_SCRATCH_W1),y
-		dey
-		lda  P8ESTACK_LO,x
-		sta  (P8ZP_SCRATCH_W1),y
-		dey
-		inx
-		lda  P8ESTACK_HI,x
-		sta  (P8ZP_SCRATCH_W1),y
-		dey
-		lda  P8ESTACK_LO,x
-		sta  (P8ZP_SCRATCH_W1),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
-
 copy_float	.proc
 		; -- copies the 5 bytes of the mflt value pointed to by P8ZP_SCRATCH_W1,
 		;    into the 5 bytes pointed to by A/Y.  Clobbers A,Y.
@@ -272,25 +139,23 @@ copy_float	.proc
 
 inc_var_f	.proc
 		; -- add 1 to float pointed to by A/Y
+		;    clobbers X
 		sta  P8ZP_SCRATCH_W1
 		sty  P8ZP_SCRATCH_W1+1
-		stx  P8ZP_SCRATCH_REG
 		jsr  MOVFM
 		lda  #<FL_ONE_const
 		ldy  #>FL_ONE_const
 		jsr  FADD
 		ldx  P8ZP_SCRATCH_W1
 		ldy  P8ZP_SCRATCH_W1+1
-		jsr  MOVMF
-		ldx  P8ZP_SCRATCH_REG
-		rts
+		jmp  MOVMF
 		.pend
 
 dec_var_f	.proc
 		; -- subtract 1 from float pointed to by A/Y
+		;    clobbers X
 		sta  P8ZP_SCRATCH_W1
 		sty  P8ZP_SCRATCH_W1+1
-		stx  P8ZP_SCRATCH_REG
 		lda  #<FL_ONE_const
 		ldy  #>FL_ONE_const
 		jsr  MOVFM
@@ -299,23 +164,7 @@ dec_var_f	.proc
 		jsr  FSUB
 		ldx  P8ZP_SCRATCH_W1
 		ldy  P8ZP_SCRATCH_W1+1
-		jsr  MOVMF
-		ldx  P8ZP_SCRATCH_REG
-		rts
-		.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
+		jmp  MOVMF
 		.pend
 
 
@@ -323,71 +172,9 @@ 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	.proc
-		; -- push the float in FAC1 onto the stack
-		stx  P8ZP_SCRATCH_REG
-_internal	ldx  #<fmath_float1
-		ldy  #>fmath_float1
-		jsr  MOVMF
-		lda  #<fmath_float1
-		ldy  #>fmath_float1
-		ldx  P8ZP_SCRATCH_REG
-		jmp  push_float
-		.pend
-
-div_f		.proc
-		; -- push f1/f2 on stack
-		jsr  pop_2_floats_f2_in_fac1
-		stx  P8ZP_SCRATCH_REG
-		lda  #<fmath_float1
-		ldy  #>fmath_float1
-		jsr  FDIV
-		jmp  push_fac1._internal
-		.pend
-
-add_f		.proc
-		; -- push f1+f2 on stack
-		jsr  pop_2_floats_f2_in_fac1
-		stx  P8ZP_SCRATCH_REG
-		lda  #<fmath_float1
-		ldy  #>fmath_float1
-		jsr  FADD
-		jmp  push_fac1._internal
-		.pend
-
-sub_f		.proc
-		; -- push f1-f2 on stack
-		jsr  pop_2_floats_f2_in_fac1
-		stx  P8ZP_SCRATCH_REG
-		lda  #<fmath_float1
-		ldy  #>fmath_float1
-		jsr  FSUB
-		jmp  push_fac1._internal
-		.pend
-
-mul_f		.proc
-		; -- push f1*f2 on stack
-		jsr  pop_2_floats_f2_in_fac1
-		stx  P8ZP_SCRATCH_REG
-		lda  #<fmath_float1
-		ldy  #>fmath_float1
-		jsr  FMULT
-		jmp  push_fac1._internal
-		.pend
-
-neg_f		.proc
-		; -- toggle the sign bit on the stack
-		lda  P8ESTACK_HI+3,x
-		eor  #$80
-		sta  P8ESTACK_HI+3,x
-		rts
-		.pend
-
 var_fac1_less_f	.proc
-		; -- is the float in FAC1 < the variable AY?
-		stx  P8ZP_SCRATCH_REG
+		; -- is the float in FAC1 < the variable AY? Result in A. Clobbers X.
 		jsr  FCOMP
-		ldx  P8ZP_SCRATCH_REG
 		cmp  #255
 		beq  +
 		lda  #0
@@ -397,10 +184,8 @@ var_fac1_less_f	.proc
 		.pend
 
 var_fac1_lesseq_f	.proc
-		; -- is the float in FAC1 <= the variable AY?
-		stx  P8ZP_SCRATCH_REG
+		; -- is the float in FAC1 <= the variable AY?  Result in A. Clobbers X.
 		jsr  FCOMP
-		ldx  P8ZP_SCRATCH_REG
 		cmp  #0
 		beq  +
 		cmp  #255
@@ -412,10 +197,8 @@ var_fac1_lesseq_f	.proc
 		.pend
 
 var_fac1_greater_f	.proc
-		; -- is the float in FAC1 > the variable AY?
-		stx  P8ZP_SCRATCH_REG
+		; -- is the float in FAC1 > the variable AY?  Result in A. Clobbers X.
 		jsr  FCOMP
-		ldx  P8ZP_SCRATCH_REG
 		cmp  #1
 		beq  +
 		lda  #0
@@ -425,10 +208,8 @@ var_fac1_greater_f	.proc
 		.pend
 
 var_fac1_greatereq_f	.proc
-		; -- is the float in FAC1 >= the variable AY?
-		stx  P8ZP_SCRATCH_REG
+		; -- is the float in FAC1 >= the variable AY?  Result in A. Clobbers X.
 		jsr  FCOMP
-		ldx  P8ZP_SCRATCH_REG
 		cmp  #0
 		beq  +
 		cmp  #1
@@ -439,17 +220,23 @@ var_fac1_greatereq_f	.proc
 		rts
 		.pend
 
+var_fac1_equal_f	.proc
+		; -- are the floats numbers in FAC1 and the variable AY *not* identical?   Result in A. Clobbers X.
+		jsr  FCOMP
+		and  #1
+		eor  #1
+		rts
+		.pend
+
 var_fac1_notequal_f	.proc
-		; -- are the floats numbers in FAC1 and the variable AY *not* identical?
-		stx  P8ZP_SCRATCH_REG
+		; -- are the floats numbers in FAC1 and the variable AY *not* identical?   Result in A. Clobbers X.
 		jsr  FCOMP
-		ldx  P8ZP_SCRATCH_REG
 		and  #1
 		rts
 		.pend
 
 vars_equal_f	.proc
-		; -- are the mflpt5 numbers in P8ZP_SCRATCH_W1 and AY identical?
+		; -- are the mflpt5 numbers in P8ZP_SCRATCH_W1 and AY identical?  Result in A
 		sta  P8ZP_SCRATCH_W2
 		sty  P8ZP_SCRATCH_W2+1
 		ldy  #0
@@ -478,51 +265,13 @@ _false		lda  #0
 		rts
 		.pend
 
-equal_f		.proc
-		; -- are the two mflpt5 numbers on the stack identical?
-		inx
-		inx
-		inx
-		inx
-		lda  P8ESTACK_LO-3,x
-		cmp  P8ESTACK_LO,x
-		bne  _equals_false
-		lda  P8ESTACK_LO-2,x
-		cmp  P8ESTACK_LO+1,x
-		bne  _equals_false
-		lda  P8ESTACK_LO-1,x
-		cmp  P8ESTACK_LO+2,x
-		bne  _equals_false
-		lda  P8ESTACK_HI-2,x
-		cmp  P8ESTACK_HI+1,x
-		bne  _equals_false
-		lda  P8ESTACK_HI-1,x
-		cmp  P8ESTACK_HI+2,x
-		bne  _equals_false
-_equals_true	lda  #1
-_equals_store	inx
-		sta  P8ESTACK_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  P8ESTACK_LO+1,x
-		rts
-		.pend
 
 vars_less_f	.proc
-		; -- is float in AY < float in P8ZP_SCRATCH_W2 ?
+		; -- is float in AY < float in P8ZP_SCRATCH_W2 ?   Result in A. Clobbers X.
 		jsr  MOVFM
 		lda  P8ZP_SCRATCH_W2
 		ldy  P8ZP_SCRATCH_W2+1
-		stx  P8ZP_SCRATCH_REG
 		jsr  FCOMP
-		ldx  P8ZP_SCRATCH_REG
 		cmp  #255
 		bne  +
 		lda  #1
@@ -532,13 +281,11 @@ vars_less_f	.proc
 		.pend
 
 vars_lesseq_f	.proc
-		; -- is float in AY <= float in P8ZP_SCRATCH_W2 ?
+		; -- is float in AY <= float in P8ZP_SCRATCH_W2 ?  Result in A. Clobbers X.
 		jsr  MOVFM
 		lda  P8ZP_SCRATCH_W2
 		ldy  P8ZP_SCRATCH_W2+1
-		stx  P8ZP_SCRATCH_REG
 		jsr  FCOMP
-		ldx  P8ZP_SCRATCH_REG
 		cmp  #255
 		bne  +
 -		lda  #1
@@ -550,7 +297,7 @@ vars_lesseq_f	.proc
 		.pend
 
 less_f		.proc
-		; -- is f1 < f2?
+		; -- is f1 < f2?    Result in A. Clobbers X.
 		jsr  compare_floats
 		cmp  #255
 		beq  compare_floats._return_true
@@ -559,7 +306,7 @@ less_f		.proc
 
 
 lesseq_f	.proc
-		; -- is f1 <= f2?
+		; -- is f1 <= f2?  Result in A. Clobbers X.
 		jsr  compare_floats
 		cmp  #255
 		beq  compare_floats._return_true
@@ -569,7 +316,7 @@ lesseq_f	.proc
 		.pend
 
 greater_f	.proc
-		; -- is f1 > f2?
+		; -- is f1 > f2?  Result in A. Clobbers X.
 		jsr  compare_floats
 		cmp  #1
 		beq  compare_floats._return_true
@@ -577,7 +324,7 @@ greater_f	.proc
 		.pend
 
 greatereq_f	.proc
-		; -- is f1 >= f2?
+		; -- is f1 >= f2?  Result in A. Clobbers X.
 		jsr  compare_floats
 		cmp  #1
 		beq  compare_floats._return_true
@@ -586,32 +333,9 @@ greatereq_f	.proc
 		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  P8ZP_SCRATCH_REG
-		jsr  FCOMP		; A = flt1 compared with flt2 (0=equal, 1=flt1>flt2, 255=flt1<flt2)
-		ldx  P8ZP_SCRATCH_REG
-		rts
-_return_false	lda  #0
-_return_result  sta  P8ESTACK_LO,x
-		dex
-		rts
-_return_true	lda  #1
-		bne  _return_result
-		.pend
-
 set_array_float_from_fac1	.proc
 		; -- set the float in FAC1 in the array (index in A, array in P8ZP_SCRATCH_W1)
+		;    clobbers X
 		sta  P8ZP_SCRATCH_B1
 		asl  a
 		asl  a
@@ -622,11 +346,8 @@ set_array_float_from_fac1	.proc
 		adc  P8ZP_SCRATCH_W1
 		bcc  +
 		iny
-+		stx  floats_store_reg
-		tax
-		jsr  MOVMF
-		ldx  floats_store_reg
-		rts
++		tax
+		jmp  MOVMF
 		.pend
 
 
@@ -669,54 +390,63 @@ set_array_float		.proc
 		.pend
 
 
-equal_zero	.proc
-		jsr  floats.pop_float_fac1
-		jsr  floats.SIGN
-		beq  _true
-		bne  _false
-_true		lda  #1
-		sta  P8ESTACK_LO,x
-		dex
-		rts
-_false		lda  #0
-		sta  P8ESTACK_LO,x
-		dex
-		rts
-		.pend
+pushFAC1    .proc
+	;-- push floating point in FAC onto the cpu stack
+	; save return address
+	pla
+	sta  P8ZP_SCRATCH_W2
+	pla
+	sta  P8ZP_SCRATCH_W2+1
+	ldx  #<floats.floats_temp_var
+	ldy  #>floats.floats_temp_var
+	jsr  floats.MOVMF
+	lda  floats.floats_temp_var
+	pha
+	lda  floats.floats_temp_var+1
+	pha
+	lda  floats.floats_temp_var+2
+	pha
+	lda  floats.floats_temp_var+3
+	pha
+	lda  floats.floats_temp_var+4
+	pha
+	; re-push return address
+	lda  P8ZP_SCRATCH_W2+1
+	pha
+	lda  P8ZP_SCRATCH_W2
+	pha
+	rts
+	.pend
 
-notequal_zero	.proc
-		jsr  floats.pop_float_fac1
-		jsr  floats.SIGN
-		bne  equal_zero._true
-		beq  equal_zero._false
-		.pend
+popFAC .proc
+	; -- pop floating point value from cpu stack into FAC1 or FAC2 (
+	;    carry flag clear=FAC1, carry set=FAC2
+	; save return address
+	pla
+	sta  P8ZP_SCRATCH_W2
+	pla
+	sta  P8ZP_SCRATCH_W2+1
+	pla
+	sta  floats.floats_temp_var+4
+	pla
+	sta  floats.floats_temp_var+3
+	pla
+	sta  floats.floats_temp_var+2
+	pla
+	sta  floats.floats_temp_var+1
+	pla
+	sta  floats.floats_temp_var
+	lda  #<floats.floats_temp_var
+	ldy  #>floats.floats_temp_var
+	bcs  +
+	jsr  floats.MOVFM
+	jmp  ++
++       jsr  floats.CONUPK
++	; re-push return address
+	lda  P8ZP_SCRATCH_W2+1
+	pha
+	lda  P8ZP_SCRATCH_W2
+	pha
+	rts
+	.pend
 
-greater_zero	.proc
-		jsr  floats.pop_float_fac1
-		jsr  floats.SIGN
-		beq  equal_zero._false
-		bpl  equal_zero._true
-		jmp  equal_zero._false
-		.pend
-
-less_zero	.proc
-		jsr  floats.pop_float_fac1
-		jsr  floats.SIGN
-		bmi  equal_zero._true
-		jmp  equal_zero._false
-		.pend
-
-greaterequal_zero	.proc
-		jsr  floats.pop_float_fac1
-		jsr  floats.SIGN
-		bpl  equal_zero._true
-		jmp  equal_zero._false
-		.pend
-
-lessequal_zero	.proc
-		jsr  floats.pop_float_fac1
-		jsr  floats.SIGN
-		beq  equal_zero._true
-		bmi  equal_zero._true
-		jmp  equal_zero._false
-		.pend

compiler/res/prog8lib/c64/floats.p8

@@ -7,8 +7,9 @@ floats {
 	; ---- this block contains C-64 floating point related functions ----
     %option no_symbol_prefixing
 
-        const float  PI     = 3.141592653589793
-        const float  TWOPI  = 6.283185307179586
+        const float  π      = 3.141592653589793
+        const float  PI     = π
+        const float  TWOPI  = 2*π
 
 
 ; ---- C64 basic and kernal ROM float constants and functions ----
@@ -46,13 +47,13 @@ romsub $b391 = GIVAYF(ubyte lo @ Y, ubyte hi @ A) clobbers(A,X,Y)
 
 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 $b7b5 = FREADSTR(ubyte length @ A) clobbers(A,X,Y)   ; str -> fac1, $22/23 must point to string, A=string length.  Also see parse_f()
 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)
 
 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 $bafe = DIV10() clobbers(A,X,Y)                      ; fac1 /= 10 , CAUTION: result is always positive! You have to fix sign manually!
 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
 
 romsub $b86a = FADDT() clobbers(A,X,Y)                      ; fac1 += fac2
@@ -77,6 +78,7 @@ 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 (fac1 = -fac1)
+romsub $b8d7 = NORMAL() clobbers(A)                         ; normalize 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)
@@ -159,12 +161,25 @@ asmsub  GETADRAY  () clobbers(X) -> uword @ AY  {
 
 sub rndf() -> float {
     %asm {{
-        stx  P8ZP_SCRATCH_REG
         lda  #1
         jsr  FREADSA
-        jsr  RND		; rng into fac1
-        ldx  P8ZP_SCRATCH_REG
-        rts
+        jmp  RND		; rng into fac1
+    }}
+}
+
+asmsub parse_f(str value @AY) -> float @FAC1 {
+    %asm {{
+        sta  $22
+        sty  $23
+        jsr  prog8_lib.strlen
+        tya
+        jmp  FREADSTR
+    }}
+}
+
+asmsub normalize(float value @FAC1) -> float @ FAC1 {
+    %asm {{
+        jmp  floats.NORMAL
     }}
 }
 

compiler/res/prog8lib/c64/floats_funcs.asm

@@ -1,13 +1,6 @@
 ; --- floating point builtin functions
 
 
-func_sign_f_stack	.proc
-		jsr  func_sign_f_into_A
-		sta  P8ESTACK_LO,x
-		dex
-		rts
-		.pend
-
 func_sign_f_into_A	.proc
 		jsr  MOVFM
 		jmp  SIGN
@@ -146,17 +139,11 @@ func_all_f_stack	.proc
 		.pend
 
 func_abs_f_into_FAC1    .proc
-        stx  P8ZP_SCRATCH_REG
         jsr  MOVFM
-        jsr  ABS
-        ldx  P8ZP_SCRATCH_REG
-        rts
+        jmp  ABS
 	.pend
 
 func_sqrt_into_FAC1     .proc
-        stx  P8ZP_SCRATCH_REG
         jsr  MOVFM
-        jsr  SQR
-        ldx  P8ZP_SCRATCH_REG
-        rts
+        jmp  SQR
 	.pend

compiler/res/prog8lib/c64/graphics.p8

@@ -1,35 +1,46 @@
-%import textio
-
 ; bitmap pixel graphics module for the C64
 ; only black/white monochrome 320x200 for now
-; assumes bitmap screen memory is $2000-$3fff
+;
+; NOTE: For sake of speed, NO BOUNDS CHECKING is performed in most routines!
+;       You'll have to make sure yourself that you're not writing outside of bitmap boundaries!
+;
+; Sets character matrix and bitmap screen memory at a higher memory location $5c00-$7fff
+; so that the program itself can be larger without starting to overwrite the graphics memory.
 
 graphics {
     %option no_symbol_prefixing
 
-    const uword BITMAP_ADDRESS = $2000
     const uword WIDTH = 320
     const ubyte HEIGHT = 200
 
+    const uword BITMAP_ADDRESS = $6000      ; MUST BE IN REGULAR RAM if you are not messing with ROM/RAM banking. (and $2000-aligned)
+                                            ; note: this constant is also used in a asm multiplication table below!
+    const uword CHARS_ADDRESS = $5c00       ; must be in same vic memory bank as the bitmap.
+
     sub enable_bitmap_mode() {
         ; enable bitmap screen, erase it and set colors to black/white.
-        c64.SCROLY = %00111011
-        c64.SCROLX = %00001000
-        c64.VMCSB = (c64.VMCSB & %11110000) | %00001000   ; $2000-$3fff
         clear_screen(1, 0)
+        c64.SCROLY = %00111011      ; enable bitmap graphics mode
+        c64.SCROLX = %00001000      ; 40 column mode, no scrolling, multicolor bitmap off
+        c64.VMCSB = (lsb(CHARS_ADDRESS >> 6) & $F0) | (lsb((BITMAP_ADDRESS & $3fff) / $0800) << 1)     ; set bitmap address
+        c64.CIA2DDRA |= %11
+        c64.CIA2PRA = lsb(BITMAP_ADDRESS >> 14) ^ 3     ; set VIC bank.
     }
 
     sub disable_bitmap_mode() {
-        ; enables text mode, erase the text screen, color white
-        c64.SCROLY = %00011011
-        c64.SCROLX = %00001000
-        c64.VMCSB = (c64.VMCSB & %11110000) | %00000100   ; $1000-$2fff
-        txt.fill_screen(' ', 1)
+        ; enables erase the text screen, text mode
+        sys.memset(CHARS_ADDRESS, 40*25, sc:' ')
+        c64.SCROLY = %00011011      ; disable bitmap graphics mode
+        c64.SCROLX = %00001000      ; 40 column mode, no scrolling
+        c64.VMCSB  = %00010100      ; screen addresses back to defaults
+        c64.CIA2DDRA |= %11
+        c64.CIA2PRA = %11   ; back to VIC bank 0.
     }
 
     sub clear_screen(ubyte pixelcolor, ubyte bgcolor) {
         sys.memset(BITMAP_ADDRESS, 320*200/8, 0)
-        txt.fill_screen(pixelcolor << 4 | bgcolor, 0)
+        sys.memset(CHARS_ADDRESS, 40*25, pixelcolor << 4 | bgcolor)
+        sys.memset(cbm.Colors, 40*25, 255)
     }
 
     sub line(uword @zp x1, ubyte @zp y1, uword @zp x2, ubyte @zp y2) {
@@ -127,46 +138,46 @@ graphics {
         }
     }
 
-    sub rect(uword x, ubyte y, uword width, ubyte height) {
+    sub rect(uword xx, ubyte yy, uword width, ubyte height) {
         if width==0 or height==0
             return
-        horizontal_line(x, y, width)
+        horizontal_line(xx, yy, width)
         if height==1
             return
-        horizontal_line(x, y+height-1, width)
-        vertical_line(x, y+1, height-2)
+        horizontal_line(xx, yy+height-1, width)
+        vertical_line(xx, yy+1, height-2)
         if width==1
             return
-        vertical_line(x+width-1, y+1, height-2)
+        vertical_line(xx+width-1, yy+1, height-2)
     }
 
-    sub fillrect(uword x, ubyte y, uword width, ubyte height) {
+    sub fillrect(uword xx, ubyte yy, uword width, ubyte height) {
         if width==0
             return
         repeat height {
-            horizontal_line(x, y, width)
-            y++
+            horizontal_line(xx, yy, width)
+            yy++
         }
     }
 
-    sub horizontal_line(uword x, ubyte y, uword length) {
+    sub horizontal_line(uword xx, ubyte yy, uword length) {
         if length<8 {
-            internal_plotx=x
+            internal_plotx=xx
             repeat lsb(length) {
-                internal_plot(y)
+                internal_plot(yy)
                 internal_plotx++
             }
             return
         }
 
-        ubyte separate_pixels = lsb(x) & 7
-        uword addr = get_y_lookup(y) + (x&$fff8)
+        ubyte separate_pixels = lsb(xx) & 7
+        uword pixaddr = get_y_lookup(yy) + (xx&$fff8)
 
         if separate_pixels {
             %asm {{
-                lda  addr
+                lda  pixaddr
                 sta  P8ZP_SCRATCH_W1
-                lda  addr+1
+                lda  pixaddr+1
                 sta  P8ZP_SCRATCH_W1+1
                 ldy  separate_pixels
                 lda  hline_filled_right,y
@@ -175,7 +186,7 @@ graphics {
                 ora  (P8ZP_SCRATCH_W1),y
                 sta  (P8ZP_SCRATCH_W1),y
             }}
-            addr += 8
+            pixaddr += 8
             length += separate_pixels
             length -= 8
         }
@@ -185,16 +196,15 @@ graphics {
                 lda  length
                 and  #7
                 sta  separate_pixels
-                stx  P8ZP_SCRATCH_REG
                 lsr  length+1
                 ror  length
                 lsr  length+1
                 ror  length
                 lsr  length+1
                 ror  length
-                lda  addr
+                lda  pixaddr
                 sta  _modified+1
-                lda  addr+1
+                lda  pixaddr+1
                 sta  _modified+2
                 lda  length
                 ora  length+1
@@ -210,8 +220,7 @@ _modified       stx  $ffff      ; modified
                 inc  _modified+2
 +               dey
                 bne  _modified
-_zero           ldx  P8ZP_SCRATCH_REG
-
+_zero
                 ldy  separate_pixels
                 beq  hline_zero2
                 lda  _modified+1
@@ -229,16 +238,17 @@ hline_zero2
         }
     }
 
-    sub vertical_line(uword x, ubyte y, ubyte height) {
-        internal_plotx = x
+    sub vertical_line(uword xx, ubyte yy, ubyte height) {
+        internal_plotx = xx
         repeat height {
-            internal_plot(y)
-            y++
+            internal_plot(yy)
+            yy++
         }
     }
 
     sub circle(uword xcenter, ubyte ycenter, ubyte radius) {
-        ; Midpoint algorithm
+        ; Warning: NO BOUNDS CHECKS. Make sure circle fits in the screen.
+        ; Midpoint algorithm.
         if radius==0
             return
         ubyte @zp ploty
@@ -267,16 +277,17 @@ hline_zero2
             internal_plotx = xcenter - yy
             internal_plot(ploty)
             yy++
-            if decisionOver2<=0
-                decisionOver2 += (yy as word)*2+1
-            else {
+            if decisionOver2>=0 {
                 radius--
-                decisionOver2 += (yy as word -radius)*2+1
+                decisionOver2 -= radius*$0002
             }
+            decisionOver2 += yy*$0002
+            decisionOver2++
         }
     }
 
     sub disc(uword xcenter, ubyte ycenter, ubyte radius) {
+        ; Warning: NO BOUNDS CHECKS. Make sure circle fits in the screen.
         ; Midpoint algorithm, filled
         if radius==0
             return
@@ -289,12 +300,12 @@ hline_zero2
             horizontal_line(xcenter-yy, ycenter+radius, yy*2+1)
             horizontal_line(xcenter-yy, ycenter-radius, yy*2+1)
             yy++
-            if decisionOver2<=0
-                decisionOver2 += (yy as word)*2+1
-            else {
+            if decisionOver2>=0 {
                 radius--
-                decisionOver2 += (yy as word -radius)*2+1
+                decisionOver2 -= radius*$0002
             }
+            decisionOver2 += yy*$0002
+            decisionOver2++
         }
     }
 
@@ -302,8 +313,8 @@ hline_zero2
 ; here is the non-asm code for the plot routine below:
 ;    sub plot_nonasm(uword px, ubyte py) {
 ;        ubyte[] ormask = [128, 64, 32, 16, 8, 4, 2, 1]
-;        uword addr = BITMAP_ADDRESS + 320*(py>>3) + (py & 7) + (px & %0000000111111000)
-;        @(addr) |= ormask[lsb(px) & 7]
+;        uword pixaddr = BITMAP_ADDRESS + 320*(py>>3) + (py & 7) + (px & %0000000111111000)
+;        @(pixaddr) |= ormask[lsb(px) & 7]
 ;    }
 
     inline asmsub  plot(uword plotx @XY, ubyte ploty @A) clobbers (A, X, Y) {
@@ -354,7 +365,7 @@ _ormask     .byte 128, 64, 32, 16, 8, 4, 2, 1
 ; the y lookup tables encodes this formula:  BITMAP_ADDRESS + 320*(py>>3) + (py & 7)    (y from 0..199)
 ; We use the 64tass syntax for range expressions to calculate this table on assembly time.
 
-_plot_y_values := $2000 + 320*(range(200)>>3) + (range(200) & 7)
+_plot_y_values := BITMAP_ADDRESS + 320*(range(200)>>3) + (range(200) & 7)
 
 _y_lookup_lo    .byte  <_plot_y_values
 _y_lookup_hi    .byte  >_plot_y_values
@@ -362,7 +373,7 @@ _y_lookup_hi    .byte  >_plot_y_values
         }}
     }
 
-    asmsub get_y_lookup(ubyte y @Y) -> uword @AY {
+    asmsub get_y_lookup(ubyte yy @Y) -> uword @AY {
         %asm {{
             lda  internal_plot._y_lookup_lo,y
             pha

compiler/res/prog8lib/c64/syslib.p8

@@ -91,7 +91,7 @@ romsub $FFC6 = CHKIN(ubyte logical @ X) clobbers(A,X) -> bool @Pc    ; (via 798
 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(X, 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 $FFD2 = CHROUT(ubyte character @ A)                      ; (via 806 ($326)) output a character
 romsub $FFD5 = LOAD(ubyte verify @ A, uword address @ XY) -> bool @Pc, ubyte @ A, uword @ XY     ; (via 816 ($330)) load from device
 romsub $FFD8 = SAVE(ubyte zp_startaddr @ A, uword endaddr @ XY) -> bool @ 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
@@ -104,34 +104,26 @@ romsub $FFED = SCREEN() -> ubyte @ X, ubyte @ Y                 ; read number of
 romsub $FFF0 = PLOT(ubyte col @ Y, ubyte row @ X, bool dir @ Pc) -> ubyte @ X, ubyte @ Y       ; read/set position of cursor on screen.  Use txt.plot for a 'safe' wrapper that preserves X.
 romsub $FFF3 = IOBASE() -> uword @ XY                           ; read base address of I/O devices
 
-asmsub STOP2() -> ubyte @A  {
+asmsub STOP2() clobbers(X) -> ubyte @A  {
     ; -- check if STOP key was pressed, returns true if so.  More convenient to use than STOP() because that only sets the carry status flag.
     %asm {{
-        txa
-        pha
         jsr  cbm.STOP
         beq  +
-        pla
-        tax
         lda  #0
         rts
-+       pla
-        tax
-        lda  #1
++       lda  #1
         rts
     }}
 }
 
-asmsub RDTIM16() -> uword @AY {
+asmsub RDTIM16() clobbers(X) -> uword @AY {
     ; --  like RDTIM() but only returning the lower 16 bits in AY for convenience
     %asm {{
-        stx  P8ZP_SCRATCH_REG
         jsr  cbm.RDTIM
         pha
         txa
         tay
         pla
-        ldx  P8ZP_SCRATCH_REG
         rts
     }}
 }
@@ -144,6 +136,8 @@ c64 {
     %option no_symbol_prefixing
 
         ; the default locations of the 8 sprite pointers (store address of sprite / 64)
+        ; (depending on the VIC bank and screen ram address selection these can be shifted around though,
+        ; see the two routines after this for a dynamic way of determining the correct memory location)
         &ubyte  SPRPTR0         = 2040
         &ubyte  SPRPTR1         = 2041
         &ubyte  SPRPTR2         = 2042
@@ -292,6 +286,39 @@ c64 {
 
 ; ---- end of SID registers ----
 
+
+    sub get_vic_memory_base() -> uword {
+        ; one of the 4 possible banks. $0000/$4000/$8000/$c000.
+        c64.CIA2DDRA |= %11
+        return ((c64.CIA2PRA & 3) ^ 3) as uword << 14
+    }
+
+    sub get_char_matrix_ptr() -> uword {
+        ; Usually the character screen matrix is at 1024-2039 (see above)
+        ; However the vic memory configuration can be altered and this moves these registers with it.
+        ; So this routine determines it dynamically from the VIC memory setup.
+        uword chars_matrix_offset = (c64.VMCSB & $f0) as uword << 6
+        return get_vic_memory_base() + chars_matrix_offset
+    }
+
+    sub get_bitmap_ptr() -> uword {
+        return get_vic_memory_base() + ((c64.VMCSB & %00001000) as uword << 10)
+    }
+
+    sub get_sprite_addr_ptrs() -> uword {
+        ; Usually the sprite address pointers are at addresses 2040-2047 (see above)
+        ; However the vic memory configuration can be altered and this moves these registers with it.
+        ; So this routine determines it dynamically from the VIC memory setup.
+        return get_char_matrix_ptr() + 1016
+    }
+
+    sub set_sprite_ptr(ubyte sprite_num, uword sprite_data_address) {
+        ; Sets the sprite data pointer to the given address.
+        ; Because it takes some time to calculate things based on the vic memory setup,
+        ; its only suitable if you're not continuously changing the data address.
+        ; Otherwise store the correct sprite data pointer location somewhere yourself and reuse it.
+        @(get_sprite_addr_ptrs() + sprite_num) = lsb(sprite_data_address / 64)
+    }
 }
 
 sys {
@@ -308,7 +335,7 @@ asmsub  init_system()  {
     ; This means that the BASIC, KERNAL and CHARGEN ROMs are banked in,
     ; the VIC, SID and CIA chips are reset, screen is cleared, and the default IRQ is set.
     ; Also a different color scheme is chosen to identify ourselves a little.
-    ; Uppercase charset is activated, and all three registers set to 0, status flags cleared.
+    ; Uppercase charset is activated.
     %asm {{
         sei
         cld
@@ -366,82 +393,77 @@ asmsub  enable_runstop_and_charsetswitch() clobbers(A) {
     }}
 }
 
-asmsub  set_irq(uword handler @AY, bool useKernal @Pc) clobbers(A)  {
+    asmsub save_prog8_internals() {
+        %asm {{
+            lda  P8ZP_SCRATCH_B1
+            sta  save_SCRATCH_ZPB1
+            lda  P8ZP_SCRATCH_REG
+            sta  save_SCRATCH_ZPREG
+            lda  P8ZP_SCRATCH_W1
+            sta  save_SCRATCH_ZPWORD1
+            lda  P8ZP_SCRATCH_W1+1
+            sta  save_SCRATCH_ZPWORD1+1
+            lda  P8ZP_SCRATCH_W2
+            sta  save_SCRATCH_ZPWORD2
+            lda  P8ZP_SCRATCH_W2+1
+            sta  save_SCRATCH_ZPWORD2+1
+            rts
+save_SCRATCH_ZPB1	.byte  0
+save_SCRATCH_ZPREG	.byte  0
+save_SCRATCH_ZPWORD1	.word  0
+save_SCRATCH_ZPWORD2	.word  0
+        }}
+    }
+
+    asmsub restore_prog8_internals() {
+        %asm {{
+            lda  save_prog8_internals.save_SCRATCH_ZPB1
+            sta  P8ZP_SCRATCH_B1
+            lda  save_prog8_internals.save_SCRATCH_ZPREG
+            sta  P8ZP_SCRATCH_REG
+            lda  save_prog8_internals.save_SCRATCH_ZPWORD1
+            sta  P8ZP_SCRATCH_W1
+            lda  save_prog8_internals.save_SCRATCH_ZPWORD1+1
+            sta  P8ZP_SCRATCH_W1+1
+            lda  save_prog8_internals.save_SCRATCH_ZPWORD2
+            sta  P8ZP_SCRATCH_W2
+            lda  save_prog8_internals.save_SCRATCH_ZPWORD2+1
+            sta  P8ZP_SCRATCH_W2+1
+            rts
+        }}
+    }
+
+asmsub  set_irq(uword handler @AY) clobbers(A)  {
 	%asm {{
-	        sta  _modified+1
-	        sty  _modified+2
-	        lda  #0
-	        rol  a
-	        sta  _use_kernal
-		sei
+	    sei
+        sta  _modified+1
+        sty  _modified+2
 		lda  #<_irq_handler
 		sta  cbm.CINV
 		lda  #>_irq_handler
 		sta  cbm.CINV+1
 		cli
 		rts
-_irq_handler    jsr  _irq_handler_init
-_modified	jsr  $ffff                      ; modified
-		jsr  _irq_handler_end
-		lda  _use_kernal
-		bne  +
-		lda  #$ff
+_irq_handler
+        jsr  sys.save_prog8_internals
+        cld
+_modified
+        jsr  $ffff                      ; modified
+        pha
+		jsr  sys.restore_prog8_internals
+		pla
+		beq  +
+		jmp  cbm.IRQDFRT		; continue with normal kernal irq routine
++		lda  #$ff
 		sta  c64.VICIRQ			; acknowledge raster irq
 		lda  c64.CIA1ICR		; acknowledge CIA1 interrupt
-		; end irq processing - don't use kernal's irq handling
 		pla
 		tay
 		pla
 		tax
 		pla
 		rti
-+		jmp  cbm.IRQDFRT		; continue with normal kernal irq routine
-
-_use_kernal     .byte  0
-
-_irq_handler_init
-		; save all zp scratch registers as these might be clobbered by the irq routine
-		lda  P8ZP_SCRATCH_B1
-		sta  IRQ_SCRATCH_ZPB1
-		lda  P8ZP_SCRATCH_REG
-		sta  IRQ_SCRATCH_ZPREG
-		lda  P8ZP_SCRATCH_W1
-		sta  IRQ_SCRATCH_ZPWORD1
-		lda  P8ZP_SCRATCH_W1+1
-		sta  IRQ_SCRATCH_ZPWORD1+1
-		lda  P8ZP_SCRATCH_W2
-		sta  IRQ_SCRATCH_ZPWORD2
-		lda  P8ZP_SCRATCH_W2+1
-		sta  IRQ_SCRATCH_ZPWORD2+1
-		; Set X to the bottom 32 bytes of the evaluation stack, to HOPEFULLY not clobber it.
-		; This leaves 128-32=96 stack entries for the main program, and 32 stack entries for the IRQ handler.
-		; We assume IRQ handlers don't contain complex expressions taking up more than that.
-		ldx  #32
-		cld
-		rts
-
-_irq_handler_end
-		; restore all zp scratch registers
-		lda  IRQ_SCRATCH_ZPB1
-		sta  P8ZP_SCRATCH_B1
-		lda  IRQ_SCRATCH_ZPREG
-		sta  P8ZP_SCRATCH_REG
-		lda  IRQ_SCRATCH_ZPWORD1
-		sta  P8ZP_SCRATCH_W1
-		lda  IRQ_SCRATCH_ZPWORD1+1
-		sta  P8ZP_SCRATCH_W1+1
-		lda  IRQ_SCRATCH_ZPWORD2
-		sta  P8ZP_SCRATCH_W2
-		lda  IRQ_SCRATCH_ZPWORD2+1
-		sta  P8ZP_SCRATCH_W2+1
-		rts
-
-IRQ_SCRATCH_ZPB1	.byte  0
-IRQ_SCRATCH_ZPREG	.byte  0
-IRQ_SCRATCH_ZPWORD1	.word  0
-IRQ_SCRATCH_ZPWORD2	.word  0
-
-		}}
+    }}
 }
 
 asmsub  restore_irq() clobbers(A) {
@@ -460,40 +482,39 @@ asmsub  restore_irq() clobbers(A) {
 	}}
 }
 
-asmsub  set_rasterirq(uword handler @AY, uword rasterpos @R0, bool useKernal @Pc) clobbers(A) {
+asmsub  set_rasterirq(uword handler @AY, uword rasterpos @R0) clobbers(A) {
 	%asm {{
-	        sta  _modified+1
-	        sty  _modified+2
-	        lda  #0
-	        rol  a
-	        sta  set_irq._use_kernal
-		lda  cx16.r0
-		ldy  cx16.r0+1
-		sei
-		jsr  _setup_raster_irq
-		lda  #<_raster_irq_handler
-		sta  cbm.CINV
-		lda  #>_raster_irq_handler
-		sta  cbm.CINV+1
-		cli
-		rts
+	    sei
+        sta  _modified+1
+        sty  _modified+2
+        lda  cx16.r0
+        ldy  cx16.r0+1
+        jsr  _setup_raster_irq
+        lda  #<_raster_irq_handler
+        sta  cbm.CINV
+        lda  #>_raster_irq_handler
+        sta  cbm.CINV+1
+        cli
+        rts
 
 _raster_irq_handler
-		jsr  set_irq._irq_handler_init
-_modified	jsr  $ffff              ; modified
-		jsr  set_irq._irq_handler_end
+		jsr  sys.save_prog8_internals
+		cld
+_modified
+        jsr  $ffff              ; modified
+        pha
+        jsr  sys.restore_prog8_internals
         lda  #$ff
         sta  c64.VICIRQ			; acknowledge raster irq
-		lda  set_irq._use_kernal
-		bne  +
-		; end irq processing - don't use kernal's irq handling
-		pla
+        pla
+        beq  +
+		jmp  cbm.IRQDFRT                ; continue with kernal irq routine
++		pla
 		tay
 		pla
 		tax
 		pla
 		rti
-+		jmp  cbm.IRQDFRT                ; continue with kernal irq routine
 
 _setup_raster_irq
 		pha
@@ -714,6 +735,20 @@ _longcopy
         }}
     }
 
+    inline asmsub disable_caseswitch() {
+        %asm {{
+            lda  #$80
+            sta  657
+        }}
+    }
+
+    inline asmsub enable_caseswitch() {
+        %asm {{
+            lda  #0
+            sta  657
+        }}
+    }
+
     inline asmsub exit(ubyte returnvalue @A) {
         ; -- immediately exit the program with a return code in the A register
         %asm {{
@@ -742,111 +777,110 @@ cx16 {
 
     ; the sixteen virtual 16-bit registers that the CX16 has defined in the zeropage
     ; they are simulated on the C64 as well but their location in memory is different
-    ; (because there's no room for them in the zeropage)
-    ; they are allocated at the bottom of the eval-stack (should be ample space unless
-    ; you're doing insane nesting of expressions...)
-    ; NOTE: the memory location of these registers can change based on the "-esa" compiler option
-    &uword r0  = $cf00
-    &uword r1  = $cf02
-    &uword r2  = $cf04
-    &uword r3  = $cf06
-    &uword r4  = $cf08
-    &uword r5  = $cf0a
-    &uword r6  = $cf0c
-    &uword r7  = $cf0e
-    &uword r8  = $cf10
-    &uword r9  = $cf12
-    &uword r10 = $cf14
-    &uword r11 = $cf16
-    &uword r12 = $cf18
-    &uword r13 = $cf1a
-    &uword r14 = $cf1c
-    &uword r15 = $cf1e
+    ; (because there's no room for them in the zeropage in the default configuration)
+    ; Note that when using ZP options that free up more of the zeropage (such as %zeropage kernalsafe)
+    ; there might be enough space to put them there after all, and the compiler will change these addresses!
+    &uword r0  = $cfe0
+    &uword r1  = $cfe2
+    &uword r2  = $cfe4
+    &uword r3  = $cfe6
+    &uword r4  = $cfe8
+    &uword r5  = $cfea
+    &uword r6  = $cfec
+    &uword r7  = $cfee
+    &uword r8  = $cff0
+    &uword r9  = $cff2
+    &uword r10 = $cff4
+    &uword r11 = $cff6
+    &uword r12 = $cff8
+    &uword r13 = $cffa
+    &uword r14 = $cffc
+    &uword r15 = $cffe
 
-    &word r0s  = $cf00
-    &word r1s  = $cf02
-    &word r2s  = $cf04
-    &word r3s  = $cf06
-    &word r4s  = $cf08
-    &word r5s  = $cf0a
-    &word r6s  = $cf0c
-    &word r7s  = $cf0e
-    &word r8s  = $cf10
-    &word r9s  = $cf12
-    &word r10s = $cf14
-    &word r11s = $cf16
-    &word r12s = $cf18
-    &word r13s = $cf1a
-    &word r14s = $cf1c
-    &word r15s = $cf1e
+    &word r0s  = $cfe0
+    &word r1s  = $cfe2
+    &word r2s  = $cfe4
+    &word r3s  = $cfe6
+    &word r4s  = $cfe8
+    &word r5s  = $cfea
+    &word r6s  = $cfec
+    &word r7s  = $cfee
+    &word r8s  = $cff0
+    &word r9s  = $cff2
+    &word r10s = $cff4
+    &word r11s = $cff6
+    &word r12s = $cff8
+    &word r13s = $cffa
+    &word r14s = $cffc
+    &word r15s = $cffe
 
-    &ubyte r0L  = $cf00
-    &ubyte r1L  = $cf02
-    &ubyte r2L  = $cf04
-    &ubyte r3L  = $cf06
-    &ubyte r4L  = $cf08
-    &ubyte r5L  = $cf0a
-    &ubyte r6L  = $cf0c
-    &ubyte r7L  = $cf0e
-    &ubyte r8L  = $cf10
-    &ubyte r9L  = $cf12
-    &ubyte r10L = $cf14
-    &ubyte r11L = $cf16
-    &ubyte r12L = $cf18
-    &ubyte r13L = $cf1a
-    &ubyte r14L = $cf1c
-    &ubyte r15L = $cf1e
+    &ubyte r0L  = $cfe0
+    &ubyte r1L  = $cfe2
+    &ubyte r2L  = $cfe4
+    &ubyte r3L  = $cfe6
+    &ubyte r4L  = $cfe8
+    &ubyte r5L  = $cfea
+    &ubyte r6L  = $cfec
+    &ubyte r7L  = $cfee
+    &ubyte r8L  = $cff0
+    &ubyte r9L  = $cff2
+    &ubyte r10L = $cff4
+    &ubyte r11L = $cff6
+    &ubyte r12L = $cff8
+    &ubyte r13L = $cffa
+    &ubyte r14L = $cffc
+    &ubyte r15L = $cffe
 
-    &ubyte r0H  = $cf01
-    &ubyte r1H  = $cf03
-    &ubyte r2H  = $cf05
-    &ubyte r3H  = $cf07
-    &ubyte r4H  = $cf09
-    &ubyte r5H  = $cf0b
-    &ubyte r6H  = $cf0d
-    &ubyte r7H  = $cf0f
-    &ubyte r8H  = $cf11
-    &ubyte r9H  = $cf13
-    &ubyte r10H = $cf15
-    &ubyte r11H = $cf17
-    &ubyte r12H = $cf19
-    &ubyte r13H = $cf1b
-    &ubyte r14H = $cf1d
-    &ubyte r15H = $cf1f
+    &ubyte r0H  = $cfe1
+    &ubyte r1H  = $cfe3
+    &ubyte r2H  = $cfe5
+    &ubyte r3H  = $cfe7
+    &ubyte r4H  = $cfe9
+    &ubyte r5H  = $cfeb
+    &ubyte r6H  = $cfed
+    &ubyte r7H  = $cfef
+    &ubyte r8H  = $cff1
+    &ubyte r9H  = $cff3
+    &ubyte r10H = $cff5
+    &ubyte r11H = $cff7
+    &ubyte r12H = $cff9
+    &ubyte r13H = $cffb
+    &ubyte r14H = $cffd
+    &ubyte r15H = $cfff
 
-    &byte r0sL  = $cf00
-    &byte r1sL  = $cf02
-    &byte r2sL  = $cf04
-    &byte r3sL  = $cf06
-    &byte r4sL  = $cf08
-    &byte r5sL  = $cf0a
-    &byte r6sL  = $cf0c
-    &byte r7sL  = $cf0e
-    &byte r8sL  = $cf10
-    &byte r9sL  = $cf12
-    &byte r10sL = $cf14
-    &byte r11sL = $cf16
-    &byte r12sL = $cf18
-    &byte r13sL = $cf1a
-    &byte r14sL = $cf1c
-    &byte r15sL = $cf1e
+    &byte r0sL  = $cfe0
+    &byte r1sL  = $cfe2
+    &byte r2sL  = $cfe4
+    &byte r3sL  = $cfe6
+    &byte r4sL  = $cfe8
+    &byte r5sL  = $cfea
+    &byte r6sL  = $cfec
+    &byte r7sL  = $cfee
+    &byte r8sL  = $cff0
+    &byte r9sL  = $cff2
+    &byte r10sL = $cff4
+    &byte r11sL = $cff6
+    &byte r12sL = $cff8
+    &byte r13sL = $cffa
+    &byte r14sL = $cffc
+    &byte r15sL = $cffe
 
-    &byte r0sH  = $cf01
-    &byte r1sH  = $cf03
-    &byte r2sH  = $cf05
-    &byte r3sH  = $cf07
-    &byte r4sH  = $cf09
-    &byte r5sH  = $cf0b
-    &byte r6sH  = $cf0d
-    &byte r7sH  = $cf0f
-    &byte r8sH  = $cf11
-    &byte r9sH  = $cf13
-    &byte r10sH = $cf15
-    &byte r11sH = $cf17
-    &byte r12sH = $cf19
-    &byte r13sH = $cf1b
-    &byte r14sH = $cf1d
-    &byte r15sH = $cf1f
+    &byte r0sH  = $cfe1
+    &byte r1sH  = $cfe3
+    &byte r2sH  = $cfe5
+    &byte r3sH  = $cfe7
+    &byte r4sH  = $cfe9
+    &byte r5sH  = $cfeb
+    &byte r6sH  = $cfed
+    &byte r7sH  = $cfef
+    &byte r8sH  = $cff1
+    &byte r9sH  = $cff3
+    &byte r10sH = $cff5
+    &byte r11sH = $cff7
+    &byte r12sH = $cff9
+    &byte r13sH = $cffb
+    &byte r14sH = $cffd
+    &byte r15sH = $cfff
 
     asmsub save_virtual_registers() clobbers(A,Y) {
         %asm {{

compiler/res/prog8lib/c64/textio.p8

@@ -1,4 +1,6 @@
 ; Prog8 definitions for the Text I/O and Screen routines for the Commodore-64
+; All routines work with Screencode character encoding, except `print`, `chrout` and `input_chars`,
+; these work with PETSCII encoding instead.
 
 %import syslib
 %import conv
@@ -39,7 +41,46 @@ asmsub column(ubyte col @A) clobbers(A, X, Y) {
     }}
 }
 
-asmsub  fill_screen (ubyte char @ A, ubyte color @ Y) clobbers(A)  {
+
+asmsub get_column() -> ubyte @Y {
+    %asm {{
+        sec
+        jmp cbm.PLOT
+    }}
+}
+
+asmsub row(ubyte rownum @A) clobbers(A, X, Y) {
+    ; ---- set the cursor on the given row (starting with 0) on the current line
+    %asm {{
+        sec
+        jsr  cbm.PLOT
+        tax
+        clc
+        jmp  cbm.PLOT
+    }}
+}
+
+asmsub get_row() -> ubyte @X {
+    %asm {{
+        sec
+        jmp cbm.PLOT
+    }}
+}
+
+sub get_cursor(uword colptr, uword rowptr) {
+    %asm {{
+        sec
+        jsr cbm.PLOT
+        tya
+        ldy #$00
+        sta (colptr),y
+        txa
+        sta (rowptr),y
+    }}
+}
+
+
+asmsub  fill_screen (ubyte character @ A, ubyte color @ Y) clobbers(A)  {
 	; ---- fill the character screen with the given fill character and character color.
 	;      (assumes screen and color matrix are at their default addresses)
 
@@ -54,7 +95,7 @@ asmsub  fill_screen (ubyte char @ A, ubyte color @ Y) clobbers(A)  {
 
 }
 
-asmsub  clear_screenchars (ubyte char @ A) clobbers(Y)  {
+asmsub  clear_screenchars (ubyte character @ A) clobbers(Y)  {
 	; ---- clear the character screen with the given fill character (leaves colors)
 	;      (assumes screen matrix is at the default address)
 	%asm {{
@@ -96,13 +137,12 @@ sub uppercase() {
     c64.VMCSB &= ~2
 }
 
-asmsub  scroll_left  (bool alsocolors @ Pc) clobbers(A, Y)  {
+asmsub  scroll_left  (bool alsocolors @ Pc) clobbers(A, X, 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  P8ZP_SCRATCH_REG
 		bcc _scroll_screen
 
 +               ; scroll the screen and the color memory
@@ -132,17 +172,15 @@ _scroll_screen  ; scroll only the screen memory
 		dey
 		bpl  -
 
-		ldx  P8ZP_SCRATCH_REG
 		rts
 	}}
 }
 
-asmsub  scroll_right  (bool alsocolors @ Pc) clobbers(A)  {
+asmsub  scroll_right  (bool alsocolors @ Pc) clobbers(A,X)  {
 	; ---- scroll the whole screen 1 character to the right
 	;      contents of the leftmost column are unchanged, you should clear/refill this yourself
 	;      Carry flag determines if screen color data must be scrolled too
 	%asm {{
-		stx  P8ZP_SCRATCH_REG
 		bcc  _scroll_screen
 
 +               ; scroll the screen and the color memory
@@ -168,17 +206,15 @@ _scroll_screen  ; scroll only the screen memory
 		dex
 		bpl  -
 
-		ldx  P8ZP_SCRATCH_REG
 		rts
 	}}
 }
 
-asmsub  scroll_up  (bool alsocolors @ Pc) clobbers(A)  {
+asmsub  scroll_up  (bool alsocolors @ Pc) clobbers(A,X)  {
 	; ---- scroll the whole screen 1 character up
 	;      contents of the bottom row are unchanged, you should refill/clear this yourself
 	;      Carry flag determines if screen color data must be scrolled too
 	%asm {{
-		stx  P8ZP_SCRATCH_REG
 		bcc  _scroll_screen
 
 +               ; scroll the screen and the color memory
@@ -204,17 +240,15 @@ _scroll_screen  ; scroll only the screen memory
 		dex
 		bpl  -
 
-		ldx  P8ZP_SCRATCH_REG
 		rts
 	}}
 }
 
-asmsub  scroll_down  (bool alsocolors @ Pc) clobbers(A)  {
+asmsub  scroll_down  (bool alsocolors @ Pc) clobbers(A,X)  {
 	; ---- scroll the whole screen 1 character down
 	;      contents of the top row are unchanged, you should refill/clear this yourself
 	;      Carry flag determines if screen color data must be scrolled too
 	%asm {{
-		stx  P8ZP_SCRATCH_REG
 		bcc  _scroll_screen
 
 +               ; scroll the screen and the color memory
@@ -240,15 +274,14 @@ _scroll_screen  ; scroll only the screen memory
 		dex
 		bpl  -
 
-		ldx  P8ZP_SCRATCH_REG
 		rts
 	}}
 }
 
-romsub $FFD2 = chrout(ubyte char @ A)    ; for consistency. You can also use cbm.CHROUT directly ofcourse.
+romsub $FFD2 = chrout(ubyte character @ A)    ; for consistency. You can also use cbm.CHROUT directly ofcourse. Note: takes a PETSCII encoded character.
 
 asmsub  print (str text @ AY) clobbers(A,Y)  {
-	; ---- print null terminated string from A/Y
+	; ---- print null terminated string, in PESCII encoding, from A/Y
 	; note: the compiler contains an optimization that will replace
 	;       a call to this subroutine with a string argument of just one char,
 	;       by just one call to cbm.CHROUT of that single char.
@@ -265,10 +298,9 @@ asmsub  print (str text @ AY) clobbers(A,Y)  {
 	}}
 }
 
-asmsub  print_ub0  (ubyte value @ A) clobbers(A,Y)  {
+asmsub  print_ub0  (ubyte value @ A) clobbers(A,X,Y)  {
 	; ---- print the ubyte in A in decimal form, with left padding 0s (3 positions total)
 	%asm {{
-		stx  P8ZP_SCRATCH_REG
 		jsr  conv.ubyte2decimal
 		pha
 		tya
@@ -276,16 +308,13 @@ asmsub  print_ub0  (ubyte value @ A) clobbers(A,Y)  {
 		pla
 		jsr  cbm.CHROUT
 		txa
-		jsr  cbm.CHROUT
-		ldx  P8ZP_SCRATCH_REG
-		rts
+		jmp  cbm.CHROUT
 	}}
 }
 
-asmsub  print_ub  (ubyte value @ A) clobbers(A,Y)  {
+asmsub  print_ub  (ubyte value @ A) clobbers(A,X,Y)  {
 	; ---- print the ubyte in A in decimal form, without left padding 0s
 	%asm {{
-		stx  P8ZP_SCRATCH_REG
 		jsr  conv.ubyte2decimal
 _print_byte_digits
 		pha
@@ -301,16 +330,13 @@ _print_byte_digits
         beq  _ones
         jsr  cbm.CHROUT
 _ones   txa
-		jsr  cbm.CHROUT
-		ldx  P8ZP_SCRATCH_REG
-		rts
+		jmp  cbm.CHROUT
 	}}
 }
 
-asmsub  print_b  (byte value @ A) clobbers(A,Y)  {
+asmsub  print_b  (byte value @ A) clobbers(A,X,Y)  {
 	; ---- print the byte in A in decimal form, without left padding 0s
 	%asm {{
-		stx  P8ZP_SCRATCH_REG
 		pha
 		cmp  #0
 		bpl  +
@@ -322,10 +348,9 @@ asmsub  print_b  (byte value @ A) clobbers(A,Y)  {
 	}}
 }
 
-asmsub  print_ubhex  (ubyte value @ A, bool prefix @ Pc) clobbers(A,Y)  {
+asmsub  print_ubhex  (ubyte value @ A, bool prefix @ Pc) clobbers(A,X,Y)  {
 	; ---- print the ubyte in A in hex form (if Carry is set, a radix prefix '$' is printed as well)
 	%asm {{
-		stx  P8ZP_SCRATCH_REG
 		bcc  +
 		pha
 		lda  #'$'
@@ -334,16 +359,13 @@ asmsub  print_ubhex  (ubyte value @ A, bool prefix @ Pc) clobbers(A,Y)  {
 +		jsr  conv.ubyte2hex
 		jsr  cbm.CHROUT
 		tya
-		jsr  cbm.CHROUT
-		ldx  P8ZP_SCRATCH_REG
-		rts
+		jmp  cbm.CHROUT
 	}}
 }
 
-asmsub  print_ubbin  (ubyte value @ A, bool prefix @ Pc) clobbers(A,Y)  {
+asmsub  print_ubbin  (ubyte value @ A, bool prefix @ Pc) clobbers(A,X,Y)  {
 	; ---- print the ubyte in A in binary form (if Carry is set, a radix prefix '%' is printed as well)
 	%asm {{
-		stx  P8ZP_SCRATCH_REG
 		sta  P8ZP_SCRATCH_B1
 		bcc  +
 		lda  #'%'
@@ -356,12 +378,11 @@ asmsub  print_ubbin  (ubyte value @ A, bool prefix @ Pc) clobbers(A,Y)  {
 +		jsr  cbm.CHROUT
 		dey
 		bne  -
-		ldx  P8ZP_SCRATCH_REG
 		rts
 	}}
 }
 
-asmsub  print_uwbin  (uword value @ AY, bool prefix @ Pc) clobbers(A,Y)  {
+asmsub  print_uwbin  (uword value @ AY, bool prefix @ Pc) clobbers(A,X,Y)  {
 	; ---- print the uword in A/Y in binary form (if Carry is set, a radix prefix '%' is printed as well)
 	%asm {{
 		pha
@@ -373,7 +394,7 @@ asmsub  print_uwbin  (uword value @ AY, bool prefix @ Pc) clobbers(A,Y)  {
 	}}
 }
 
-asmsub  print_uwhex  (uword value @ AY, bool prefix @ Pc) clobbers(A,Y)  {
+asmsub  print_uwhex  (uword value @ AY, bool prefix @ Pc) clobbers(A,X,Y)  {
 	; ---- print the uword in A/Y in hexadecimal form (4 digits)
 	;      (if Carry is set, a radix prefix '$' is printed as well)
 	%asm {{
@@ -386,10 +407,9 @@ asmsub  print_uwhex  (uword value @ AY, bool prefix @ Pc) clobbers(A,Y)  {
 	}}
 }
 
-asmsub  print_uw0  (uword value @ AY) clobbers(A,Y)  {
+asmsub  print_uw0  (uword value @ AY) clobbers(A,X,Y)  {
 	; ---- print the uword in A/Y in decimal form, with left padding 0s (5 positions total)
 	%asm {{
-	    stx  P8ZP_SCRATCH_REG
 		jsr  conv.uword2decimal
 		ldy  #0
 -		lda  conv.uword2decimal.decTenThousands,y
@@ -397,17 +417,14 @@ asmsub  print_uw0  (uword value @ AY) clobbers(A,Y)  {
 		jsr  cbm.CHROUT
 		iny
 		bne  -
-+		ldx  P8ZP_SCRATCH_REG
-		rts
++		rts
 	}}
 }
 
-asmsub  print_uw  (uword value @ AY) clobbers(A,Y)  {
+asmsub  print_uw  (uword value @ AY) clobbers(A,X,Y)  {
 	; ---- print the uword in A/Y in decimal form, without left padding 0s
 	%asm {{
-	    stx  P8ZP_SCRATCH_REG
 		jsr  conv.uword2decimal
-		ldx  P8ZP_SCRATCH_REG
 		ldy  #0
 -		lda  conv.uword2decimal.decTenThousands,y
 		beq  _allzero
@@ -428,7 +445,7 @@ _allzero
 	}}
 }
 
-asmsub  print_w  (word value @ AY) clobbers(A,Y)  {
+asmsub  print_w  (word value @ AY) clobbers(A,X,Y)  {
 	; ---- print the (signed) word in A/Y in decimal form, without left padding 0's
 	%asm {{
 		cpy  #0
@@ -450,7 +467,8 @@ asmsub  print_w  (word value @ AY) clobbers(A,Y)  {
 }
 
 asmsub  input_chars  (uword buffer @ AY) clobbers(A) -> ubyte @ Y  {
-	; ---- Input a string (max. 80 chars) from the keyboard. Returns length in Y. (string is terminated with a 0 byte as well)
+	; ---- Input a string (max. 80 chars) from the keyboard, in PETSCII encoding.
+	;      Returns length in Y. (string is terminated with a 0 byte as well)
 	;      It assumes the keyboard is selected as I/O channel!
 
 	%asm {{
@@ -489,7 +507,7 @@ asmsub  setchr  (ubyte col @X, ubyte row @Y, ubyte character @A) clobbers(A, Y)
 _mod		sta  $ffff		; modified
 		rts
 
-_screenrows	.word  $0400 + range(0, 1000, 40)
+_screenrows	.word  cbm.Screen + range(0, 1000, 40)
 	}}
 }
 
@@ -556,7 +574,7 @@ _mod		lda  $ffff		; modified
 	}}
 }
 
-sub  setcc  (ubyte column, ubyte row, ubyte char, ubyte charcolor)  {
+sub  setcc  (ubyte col, ubyte row, ubyte character, ubyte charcolor)  {
 	; ---- set char+color at the given position on the screen
 	%asm {{
 		lda  row
@@ -568,13 +586,13 @@ sub  setcc  (ubyte column, ubyte row, ubyte char, ubyte charcolor)  {
 		sta  _colormod+2
 		lda  setchr._screenrows,y
 		clc
-		adc  column
+		adc  col
 		sta  _charmod+1
 		sta  _colormod+1
 		bcc  +
 		inc  _charmod+2
 		inc  _colormod+2
-+		lda  char
++		lda  character
 _charmod	sta  $ffff		; modified
 		lda  charcolor
 _colormod	sta  $ffff		; modified
@@ -582,15 +600,10 @@ _colormod	sta  $ffff		; modified
 	}}
 }
 
-asmsub  plot  (ubyte col @ Y, ubyte row @ A) clobbers(A) {
-	; ---- safe wrapper around PLOT kernal routine, to save the X register.
+asmsub  plot  (ubyte col @ Y, ubyte row @ X) {
 	%asm  {{
-		stx  P8ZP_SCRATCH_REG
-		tax
 		clc
-		jsr  cbm.PLOT
-		ldx  P8ZP_SCRATCH_REG
-		rts
+		jmp  cbm.PLOT
 	}}
 }
 
@@ -612,4 +625,11 @@ asmsub height() clobbers(X, Y) -> ubyte @A {
     }}
 }
 
+asmsub waitkey() -> ubyte @A {
+    %asm {{
+-       jsr cbm.GETIN
+        beq -
+        rts
+    }}
+}
 }

compiler/res/prog8lib/conv.p8

@@ -8,25 +8,22 @@ conv {
 
     str  @shared string_out = "????????????????"       ; result buffer for the string conversion routines
 
-asmsub  str_ub0  (ubyte value @ A) clobbers(A,Y)  {
+asmsub  str_ub0  (ubyte value @ A) clobbers(A,X,Y)  {
 	; ---- convert the ubyte in A in decimal string form, with left padding 0s (3 positions total)
 	%asm {{
-            stx  P8ZP_SCRATCH_REG
             jsr  conv.ubyte2decimal
             sty  string_out
             sta  string_out+1
             stx  string_out+2
             lda  #0
             sta  string_out+3
-            ldx  P8ZP_SCRATCH_REG
             rts
 	}}
 }
 
-asmsub  str_ub  (ubyte value @ A) clobbers(A,Y)  {
+asmsub  str_ub  (ubyte value @ A) clobbers(A,X,Y)  {
 	; ---- convert the ubyte in A in decimal string form, without left padding 0s
 	%asm {{
-		stx  P8ZP_SCRATCH_REG
 		ldy  #0
 		sty  P8ZP_SCRATCH_B1
 		jsr  conv.ubyte2decimal
@@ -52,15 +49,13 @@ _output_byte_digits
                 iny
                 lda  #0
                 sta  string_out,y
-                ldx  P8ZP_SCRATCH_REG
                 rts
 	}}
 }
 
-asmsub  str_b  (byte value @ A) clobbers(A,Y)  {
+asmsub  str_b  (byte value @ A) clobbers(A,X,Y)  {
 	; ---- convert the byte in A in decimal string form, without left padding 0s
 	%asm {{
-            stx  P8ZP_SCRATCH_REG
             ldy  #0
             sty  P8ZP_SCRATCH_B1
             cmp  #0
@@ -75,7 +70,7 @@ asmsub  str_b  (byte value @ A) clobbers(A,Y)  {
 	}}
 }
 
-asmsub  str_ubhex  (ubyte value @ A) clobbers(A,Y)  {
+asmsub  str_ubhex  (ubyte value @ A) clobbers(A,X,Y)  {
 	; ---- convert the ubyte in A in hex string form
 	%asm {{
             jsr  conv.ubyte2hex
@@ -87,7 +82,7 @@ asmsub  str_ubhex  (ubyte value @ A) clobbers(A,Y)  {
 	}}
 }
 
-asmsub  str_ubbin  (ubyte value @ A) clobbers(A,Y)  {
+asmsub  str_ubbin  (ubyte value @ A) clobbers(A,X,Y)  {
 	; ---- convert the ubyte in A in binary string form
 	%asm {{
 	    sta  P8ZP_SCRATCH_B1
@@ -106,7 +101,7 @@ _digit      sta  string_out,y
 	}}
 }
 
-asmsub  str_uwbin  (uword value @ AY) clobbers(A,Y)  {
+asmsub  str_uwbin  (uword value @ AY) clobbers(A,X,Y)  {
 	; ---- convert the uword in A/Y in binary string form
 	%asm {{
 	    sta  P8ZP_SCRATCH_REG
@@ -145,10 +140,9 @@ asmsub  str_uwhex  (uword value @ AY) clobbers(A,Y)  {
 	}}
 }
 
-asmsub  str_uw0  (uword value @ AY) clobbers(A,Y)  {
+asmsub  str_uw0  (uword value @ AY) clobbers(A,X,Y)  {
 	; ---- convert the uword in A/Y in decimal string form, with left padding 0s (5 positions total)
 	%asm {{
-	    stx  P8ZP_SCRATCH_REG
 	    jsr  conv.uword2decimal
 	    ldy  #0
 -           lda  conv.uword2decimal.decTenThousands,y
@@ -156,15 +150,13 @@ asmsub  str_uw0  (uword value @ AY) clobbers(A,Y)  {
             beq  +
             iny
             bne  -
-+           ldx  P8ZP_SCRATCH_REG
-	    rts
++	    rts
 	}}
 }
 
-asmsub  str_uw  (uword value @ AY) clobbers(A,Y)  {
+asmsub  str_uw  (uword value @ AY) clobbers(A,X,Y)  {
 	; ---- convert the uword in A/Y in decimal string form, without left padding 0s
 	%asm {{
-	    stx  P8ZP_SCRATCH_REG
 	    jsr  conv.uword2decimal
 	    ldx  #0
 _output_digits
@@ -182,7 +174,6 @@ _gotdigit   sta  string_out,x
             bne  _gotdigit
 _end        lda  #0
             sta  string_out,x
-            ldx  P8ZP_SCRATCH_REG
             rts
 
 _allzero    lda  #'0'
@@ -192,12 +183,11 @@ _allzero    lda  #'0'
 	}}
 }
 
-asmsub  str_w  (word value @ AY) clobbers(A,Y)  {
+asmsub  str_w  (word value @ AY) clobbers(A,X,Y)  {
 	; ---- convert the (signed) word in A/Y in decimal string form, without left padding 0's
 	%asm {{
 	    cpy  #0
 	    bpl  str_uw
-	    stx  P8ZP_SCRATCH_REG
 	    pha
 	    lda  #'-'
 	    sta  string_out
@@ -700,10 +690,9 @@ asmsub  byte2decimal  (byte value @A) -> ubyte @Y, ubyte @A, ubyte @X  {
 	}}
 }
 
-asmsub  ubyte2hex  (ubyte value @A) -> ubyte @A, ubyte @Y  {
+asmsub  ubyte2hex  (ubyte value @A) clobbers(X) -> ubyte @A, ubyte @Y  {
 	; ---- A to hex petscii string in AY (first hex char in A, second hex char in Y)
 	%asm {{
-		stx  P8ZP_SCRATCH_REG
 		pha
 		and  #$0f
 		tax
@@ -715,7 +704,6 @@ asmsub  ubyte2hex  (ubyte value @A) -> ubyte @A, ubyte @Y  {
 		lsr  a
 		tax
 		lda  _hex_digits,x
-		ldx  P8ZP_SCRATCH_REG
 		rts
 
 _hex_digits	.text "0123456789abcdef"	; can probably be reused for other stuff as well

compiler/res/prog8lib/cx16/bmx.p8

@@ -0,0 +1,361 @@
+; Routines to load and save "BMX" files (commander X16 bitmap format) Version 1.
+; Only uncompressed images are supported for now.
+; BMX Specification: https://cx16forum.com/forum/viewtopic.php?t=6945
+
+%import diskio
+
+bmx {
+
+    ubyte[32] header
+    str FILEID = petscii:"bmx"
+
+    ubyte bitsperpixel          ; consider using set_bpp() when setting this
+    ubyte vera_colordepth       ; consider using set_vera_colordepth() when setting this
+    uword width
+    uword height
+    ubyte border
+    uword palette_entries       ; 1-256
+    ubyte palette_start
+    ubyte compression
+    uword palette_buffer_ptr = 0    ; should you want to load or save the palette into main memory instead of directly into vram
+
+    uword error_message             ; pointer to error message, or 0 if all ok
+    ubyte old_drivenumber
+
+    sub open(ubyte drivenumber, str filename) -> bool {
+        ; Open a BMX bitmap file and reads the header information.
+        ; Returns true if all is ok, false otherwise + error_message will be set.
+        error_message = 0
+        old_drivenumber = diskio.drivenumber
+        diskio.drivenumber = drivenumber
+        if diskio.f_open(filename) {
+            diskio.reset_read_channel()
+            if read_header() {
+                if parse_header() {
+                    if palette_entries>0 {
+                        if width<=640 {
+                            return true
+                        } else
+                            error_message = "image too large"
+                    } else
+                        error_message = "invalid bmx file"
+                } ; note: parse_header sets the error message by itself
+            } else
+                error_message = "invalid bmx file"
+        } else
+            error_message = diskio.status()
+
+        close()
+        return false
+    }
+
+    sub close() {
+        ; if you want to close the file before actually loading palette or bitmap data.
+        diskio.f_close()
+        diskio.drivenumber = old_drivenumber
+    }
+
+    sub continue_load(ubyte vbank, uword vaddr) -> bool {
+        ; Continues loading the palette and bitmap data from the opened BMX file.
+        ; Parameters: the vram bank and address where the bitmap data should go.
+        ; You can set palette_buffer_ptr if you want the palette buffered rather than directly into vram.
+        ; Note: does not change vera screen mode or colordepth! You have to do that yourself!
+        ; Returns true if all is ok, false otherwise + error_message will be set.
+        error_message = 0
+        diskio.reset_read_channel()
+        if width==320 or width==640 {
+            if compression==0 {
+                if read_palette() {
+                    if not read_bitmap(vbank, vaddr)
+                        error_message = "bitmap error"
+                } else
+                    error_message = "palette error"
+            } else
+                error_message = "compression not supported"
+        } else
+            error_message = "width not 320 or 640"      ; note: use continue_load_stamp() to read other sizes
+
+        close()
+        return error_message==0
+    }
+
+    sub continue_load_stamp(ubyte vbank, uword vaddr, uword screenwidth) -> bool {
+        ; Continues loading the palette and bitmap "stamp" data from the opened BMX file.
+        ; "Stamp" means: load an image that is smaller than the screen (so we need to pad around it)
+        ; Parameters:the vram bank and address where the bitmap data should go,
+        ; and the screen width that the stamp image is loaded into.
+        ; You can set palette_buffer_ptr if you want the palette buffered rather than directly into vram.
+        ; Note: does not change vera screen mode or colordepth! You have to do that yourself!
+        ; Returns true if all is ok, false otherwise + error_message will be set.
+        error_message = 0
+        diskio.reset_read_channel()
+        if compression==0 {
+            if read_palette() {
+                if not read_bitmap_padded(vbank, vaddr, screenwidth)
+                    error_message = "bitmap error"
+            } else
+                error_message = "palette error"
+        } else
+            error_message = "compression not supported"
+
+        close()
+        return error_message==0
+    }
+
+    sub continue_load_only_palette() -> bool {
+        ; Continues loading the palette but not the bitmap data from the opened BMX file.
+        ; You can set palette_buffer_ptr if you want the palette buffered rather than directly into vram.
+        ; Returns true if all is ok, false otherwise + error_message will be set.
+        ; Afterwards the file is closed and you can no longer read additional data from it!
+        error_message = 0
+        diskio.reset_read_channel()
+        if not read_palette()
+            error_message = "palette error"
+        close()
+        return error_message==0
+    }
+
+    sub save(ubyte drivenumber, str filename, ubyte vbank, uword vaddr, uword screenwidth) -> bool {
+        ; Save bitmap and palette data from vram into a BMX file.
+        ; First you must have set all bmx.* variables to the correct values! (like width, height..)
+        ; Parameters:
+        ; drive number and filename to save to,
+        ; vram bank and address of the bitmap data to save,
+        ; and optionally the screen width if you want to save a "stamp" that's smaller than the screen.
+        ; If you're saving the whole screen width, you can leave screenwidth at 0.
+        ; Returns: success status. If false, error_message points to the error message string.
+        error_message = 0
+        if compression {
+            error_message = "compression not supported"
+            return false
+        }
+        if screenwidth==0 {
+            if width!=320 and width!=640 {
+                error_message = "width not 320 or 640"
+                return false
+            }
+        } else {
+            if width>screenwidth {
+                error_message = "image too large"
+                return false
+            }
+        }
+
+        old_drivenumber = diskio.drivenumber
+        diskio.drivenumber = drivenumber
+        if diskio.f_open_w(filename) {
+            cx16.r0 = diskio.status()
+            if cx16.r0[0]!='0' {
+                error_message = cx16.r0
+                goto save_end
+            }
+            diskio.reset_write_channel()
+            if write_header() {
+                if write_palette() {
+                    if not write_bitmap(vbank, vaddr, screenwidth)
+                        error_message = "bitmap error"
+                } else
+                    error_message = "palette error"
+            } else
+                error_message = "header error"
+        } else
+             error_message = diskio.status()
+save_end:
+        diskio.f_close_w()
+        diskio.drivenumber = old_drivenumber
+        return error_message==0
+    }
+
+    sub set_bpp(ubyte bpp) {
+        ubyte[8] depths = [0,1,1,2,2,2,2,3]
+        vera_colordepth = depths[bpp-1]
+    }
+
+    sub set_vera_colordepth(ubyte depth) {
+        vera_colordepth = depth
+        bitsperpixel = 1 << depth
+    }
+
+; ------------------- helper routines, usually not needed to call yourself -------------------------
+
+    sub read_header() -> bool {
+        ; load a BMX header from the currently active input file
+        for cx16.r0L in 0 to sizeof(header)-1 {
+            header[cx16.r0L] = cbm.CHRIN()
+        }
+        return not cbm.READST()
+    }
+
+    sub read_palette() -> bool {
+        ; load palette data from the currently active input file
+        ; if palette_buffer_ptr is not 0, the palette data is read into that memory buffer,
+        ; otherwise it is read directly into the palette in vram.
+        cx16.vaddr(1, $fa00+palette_start*2, 0, 1)
+        cx16.r3 = palette_buffer_ptr
+        cx16.r2L = lsb(palette_entries)
+        do {
+            cx16.r4L = cbm.CHRIN()
+            cx16.r4H = cbm.CHRIN()
+            if cx16.r3 {
+                pokew(cx16.r3, cx16.r4)             ; into memory
+                cx16.r3+=2
+            } else {
+                cx16.VERA_DATA0 = cx16.r4L          ; into vram
+                cx16.VERA_DATA0 = cx16.r4H
+            }
+            cx16.r2L--
+        } until cx16.r2L==0
+        return cbm.READST()==0 or cbm.READST()&$40    ; no error or eof?
+    }
+
+    sub read_bitmap_padded(ubyte vbank, uword vaddr, uword screenwidth) -> bool {
+        ; load bitmap "stamp" into vram from the currently active input file
+        cx16.r3 = bytes_per_scanline(width)         ; num bytes per image scanline
+        cx16.r2 = bytes_per_scanline(screenwidth)   ; num bytes per screen scanline
+        repeat height {
+            cx16.vaddr(vbank, vaddr, 0, 1)
+            read_scanline(cx16.r3)
+            vaddr += cx16.r2
+            if_cs
+                vbank++
+        }
+        return cbm.READST()==0 or cbm.READST()&$40    ; no error or eof?
+    }
+
+    sub read_bitmap(ubyte vbank, uword vaddr) -> bool {
+        ; load contiguous bitmap into vram from the currently active input file
+        cx16.r3 = bytes_per_scanline(width)
+        cx16.vaddr(vbank, vaddr, 0, 1)
+        repeat height
+            read_scanline(cx16.r3)
+        return cbm.READST()==0 or cbm.READST()&$40    ; no error or eof?
+    }
+
+    sub read_scanline(uword size) {
+        while size {
+            cx16.r0 = cx16.MACPTR(min(255, size) as ubyte, &cx16.VERA_DATA0, true)
+            if_cs {
+                ; no MACPTR support
+                repeat size
+                    cx16.VERA_DATA0 = cbm.CHRIN()
+                return
+            }
+            size -= cx16.r0
+        }
+    }
+
+    sub write_header() -> bool {
+        ; save out the BMX header to the currently active output file
+        build_header()
+        for cx16.r0L in 0 to sizeof(header)-1 {
+            cbm.CHROUT(header[cx16.r0L])
+        }
+        return not cbm.READST()
+    }
+
+    sub write_palette() -> bool {
+        ; write palette data to the currently active input file
+        ; if palette_buffer_ptr is not 0, the palette data is read from that memory buffer,
+        ; otherwise it is read directly from the palette in vram.
+        cx16.r3 = palette_buffer_ptr
+        cx16.r2L = lsb(palette_entries)
+        cx16.vaddr(1, $fa00+palette_start*2, 0, 1)
+        do {
+            if cx16.r3 {
+                cbm.CHROUT(@(cx16.r3))      ; from memory
+                cx16.r3++
+                cbm.CHROUT(@(cx16.r3))
+                cx16.r3++
+            } else {
+                cbm.CHROUT(cx16.VERA_DATA0) ; from vram
+                cbm.CHROUT(cx16.VERA_DATA0)
+            }
+            cx16.r2L--
+        } until cx16.r2L==0
+        return not cbm.READST()
+    }
+
+    sub write_bitmap(ubyte vbank, uword vaddr, uword screenwidth) -> bool {
+        ; screenwidth=0: save contiguous bitmap from vram to the currently active output file
+        ; screenwidth>0: save "stamp" bitmap from vram to the currently active output file
+        cx16.vaddr(vbank, vaddr, 0, 1)
+        cx16.r3 = bytes_per_scanline(width)         ; num bytes per image scanline
+        cx16.r2 = 0
+        if screenwidth
+            cx16.r2 = bytes_per_scanline(screenwidth-width)   ; num bytes padding per screen scanline
+        repeat height {
+            write_scanline(cx16.r3)
+            repeat cx16.r2
+                cx16.r0L = cx16.VERA_DATA0
+        }
+        return not cbm.READST()
+
+        sub write_scanline(uword size) {
+            while size {
+                cx16.r0L = lsb(size)
+                if msb(size)
+                    cx16.r0L = 0        ; 256 bytes
+                cx16.r0 = cx16.MCIOUT(cx16.r0L, &cx16.VERA_DATA0, true)
+                if_cs {
+                    ; no MCIOUT support
+                    repeat size
+                        cbm.CHROUT(cx16.VERA_DATA0)
+                    return
+                }
+                size -= cx16.r0
+            }
+        }
+    }
+
+    sub bytes_per_scanline(uword w) -> uword {
+        ubyte[4] shifts = [3,2,1,0]
+        return w >> shifts[vera_colordepth]
+    }
+
+    sub parse_header() -> bool {
+        if header[0]==FILEID[0] and header[1]==FILEID[1] and header[2]==FILEID[2] {
+            if header[3]==1 {       ; only version 1 supported for now
+                bitsperpixel = header[4]
+                vera_colordepth = header[5]
+                width = peekw(&header+6)
+                height = peekw(&header+8)
+                palette_entries = header[10]
+                if palette_entries==0
+                    palette_entries=256
+                palette_start = header[11]
+                ; the data offset is not needed:  data_offset = peekw(&header+12)
+                compression = header[14]
+                border = header[15]
+                return true
+            } else
+                error_message = "unsupported bmx file version"
+        } else
+            error_message = "invalid bmx file"
+
+        return false
+    }
+
+    sub build_header() {
+        ; build the internal BMX header structure
+        ; normally you don't have to call this yourself
+        sys.memset(header, sizeof(header), 0)
+        uword data_offset = palette_entries*$0002
+        data_offset += sizeof(header)
+        header[0] = FILEID[0]
+        header[1] = FILEID[1]
+        header[2] = FILEID[2]
+        header[3] = 1        ; version 1
+        header[4] = bitsperpixel
+        header[5] = vera_colordepth
+        header[6] = lsb(width)
+        header[7] = msb(width)
+        header[8] = lsb(height)
+        header[9] = msb(height)
+        header[10] = lsb(palette_entries)
+        header[11] = palette_start
+        header[12] = lsb(data_offset)
+        header[13] = msb(data_offset)
+        header[14] = compression
+        header[15] = border
+    }
+}

compiler/res/prog8lib/cx16/diskio.p8

@@ -1,6 +1,16 @@
 ; Commander X16 disk drive I/O routines.
 ; Largely compatible with the default C64 ones, but adds more stuff specific to the X16 as well.
 
+; NOTE: If you experience weird behavior with these routines and you are using them
+;       in the X16 emulator using HostFs, please try again with an SD-card image instead first.
+;       It is possible that there are still small differences between HostFS and actual CBM DOS in the emulator.
+;
+; About the secondary addresses:
+; for writes (new files or overwrites), you can use 1 (without the mode string) or 2-14 (with the mode string)
+; for reads (existing files) you can use 0 or 2-14 (mode string is optional)
+; for modify mode (new files* or existing files), you must use 2-14, and the mode string ,s,m is required
+
+
 %import textio
 %import string
 %import syslib
@@ -8,22 +18,29 @@
 diskio {
     %option no_symbol_prefixing
 
-    ubyte drivenumber = 8
+    const ubyte READ_IO_CHANNEL=12
+    const ubyte WRITE_IO_CHANNEL=13
 
-    sub set_drive(ubyte number) {
-        drivenumber = number
+    ubyte drivenumber = 8           ; user programs can set this to the drive number they want to load/save to!
+
+    sub reset_read_channel() {
+        void cbm.CHKIN(READ_IO_CHANNEL)
+    }
+
+    sub reset_write_channel() {
+        cbm.CHKOUT(WRITE_IO_CHANNEL)
     }
 
     sub directory() -> bool {
         ; -- Prints the directory contents to the screen. Returns success.
 
         cbm.SETNAM(1, "$")
-        cbm.SETLFS(12, drivenumber, 0)
+        cbm.SETLFS(READ_IO_CHANNEL, drivenumber, 0)
         ubyte status = 1
         void cbm.OPEN()          ; open 12,8,0,"$"
         if_cs
             goto io_error
-        void cbm.CHKIN(12)        ; use #12 as input channel
+        reset_read_channel()
         if_cs
             goto io_error
 
@@ -43,12 +60,12 @@ diskio {
             ubyte high = cbm.CHRIN()
             txt.print_uw(mkword(high, low))
             txt.spc()
-            ubyte @zp char
+            ubyte @zp character
             repeat {
-                char = cbm.CHRIN()
-                if char==0
+                character = cbm.CHRIN()
+                if character==0
                     break
-                txt.chrout(char)
+                txt.chrout(character)
             }
             txt.nl()
             void cbm.CHRIN()     ; skip 2 bytes
@@ -61,7 +78,7 @@ diskio {
 
 io_error:
         cbm.CLRCHN()        ; restore default i/o devices
-        cbm.CLOSE(12)
+        cbm.CLOSE(READ_IO_CHANNEL)
 
         if status and status & $40 == 0 {            ; bit 6=end of file
             txt.print("\ni/o error, status: ")
@@ -76,12 +93,12 @@ io_error:
     sub diskname() -> uword {
         ; returns disk label name or 0 if error
         cbm.SETNAM(3, "$")
-        cbm.SETLFS(12, diskio.drivenumber, 0)
+        cbm.SETLFS(READ_IO_CHANNEL, drivenumber, 0)
         ubyte status = 1
         void cbm.OPEN()          ; open 12,8,0,"$=c"
         if_cs
             goto io_error
-        void cbm.CHKIN(12)        ; use #12 as input channel
+        reset_read_channel()
         if_cs
             goto io_error
 
@@ -89,12 +106,12 @@ io_error:
             ; skip up to entry name
         }
 
-        cx16.r0 = &diskio.list_filename
+        cx16.r0 = &list_filename
         repeat {
             @(cx16.r0) = cbm.CHRIN()
             if @(cx16.r0)=='"' {
                 @(cx16.r0) = ' '
-                while @(cx16.r0)==' ' and cx16.r0>=&diskio.list_filename {
+                while @(cx16.r0)==' ' and cx16.r0>=&list_filename {
                     @(cx16.r0) = 0
                     cx16.r0--
                 }
@@ -106,10 +123,10 @@ io_error:
 
 io_error:
         cbm.CLRCHN()
-        cbm.CLOSE(12)
+        cbm.CLOSE(READ_IO_CHANNEL)
         if status and status & $40 == 0
             return 0
-        return diskio.list_filename
+        return list_filename
     }
 
     ; internal variables for the iterative file lister / loader
@@ -124,12 +141,13 @@ io_error:
 
     sub list_filenames(uword pattern_ptr, uword filenames_buffer, uword filenames_buf_size) -> ubyte {
         ; -- fill the provided buffer with the names of the files on the disk (until buffer is full).
-        ;    Files in the buffer are separeted by a 0 byte. You can provide an optional pattern to match against.
+        ;    Files in the buffer are separated by a 0 byte. You can provide an optional pattern to match against.
         ;    After the last filename one additional 0 byte is placed to indicate the end of the list.
         ;    Returns number of files (it skips 'dir' entries i.e. subdirectories).
         ;    Also sets carry on exit: Carry clear = all files returned, Carry set = directory has more files that didn't fit in the buffer.
         uword buffer_start = filenames_buffer
         ubyte files_found = 0
+        filenames_buffer[0]=0
         if lf_start_list(pattern_ptr) {
             while lf_next_entry() {
                 if list_filetype!="dir" {
@@ -150,7 +168,7 @@ io_error:
         return files_found
     }
 
-    ; ----- iterative file lister functions (uses io channel 12) -----
+    ; ----- iterative file lister functions (uses the read io channel) -----
 
     sub lf_start_list(uword pattern_ptr) -> bool {
         ; -- start an iterative file listing with optional pattern matching.
@@ -161,11 +179,11 @@ io_error:
         iteration_in_progress = true
 
         cbm.SETNAM(1, "$")
-        cbm.SETLFS(12, drivenumber, 0)
+        cbm.SETLFS(READ_IO_CHANNEL, drivenumber, 0)
         void cbm.OPEN()          ; open 12,8,0,"$"
         if_cs
             goto io_error
-        void cbm.CHKIN(12)        ; use #12 as input channel
+        reset_read_channel()
         if_cs
             goto io_error
 
@@ -190,7 +208,7 @@ io_error:
             return false
 
         repeat {
-            void cbm.CHKIN(12)        ; use #12 as input channel again
+            reset_read_channel()        ; use the input io channel again
 
             uword nameptr = &list_filename
             ubyte blocks_lsb = cbm.CHRIN()
@@ -209,12 +227,12 @@ io_error:
 
             ; read the filename
             repeat {
-                ubyte char = cbm.CHRIN()
-                if char==0
+                ubyte character = cbm.CHRIN()
+                if character==0
                     break
-                if char=='\"'
+                if character=='\"'
                     break
-                @(nameptr) = char
+                @(nameptr) = character
                 nameptr++
             }
 
@@ -251,32 +269,36 @@ close_end:
         ; -- end an iterative file listing session (close channels).
         if iteration_in_progress {
             cbm.CLRCHN()
-            cbm.CLOSE(12)
+            cbm.CLOSE(READ_IO_CHANNEL)
             iteration_in_progress = false
         }
     }
 
 
-    ; ----- iterative file loader functions (uses io channel 12) -----
+    ; ----- iterative file loader functions (uses the read io channel) -----
 
-    sub f_open(uword filenameptr) -> bool {
+    sub f_open(str filenameptr) -> bool {
         ; -- open a file for iterative reading with f_read
         ;    note: only a single iteration loop can be active at a time!
+        ;    Returns true if the file is successfully opened and readable.
+        ;    No need to check status(), unlike f_open_w() !
+        ;    NOTE: the default input isn't yet set to this logical file, you must use reset_read_channel() to do this,
+        ;          if you're going to read from it yourself instead of using f_read()!
         f_close()
 
         cbm.SETNAM(string.length(filenameptr), filenameptr)
-        cbm.SETLFS(12, drivenumber, 12)     ; note: has to be 12,x,12 because otherwise f_seek doesn't work
+        cbm.SETLFS(READ_IO_CHANNEL, drivenumber, READ_IO_CHANNEL)     ; note: has to be Channel,x,Channel because otherwise f_seek doesn't work
         void cbm.OPEN()          ; open 12,8,12,"filename"
         if_cc {
             if cbm.READST()==0 {
                 iteration_in_progress = true
-                void cbm.CHKIN(12)          ; use #12 as input channel
+                reset_read_channel()
                 if_cc {
                     void cbm.CHRIN()        ; read first byte to test for file not found
                     if not cbm.READST() {
-                        cbm.CLOSE(12)           ; close file because we already consumed first byte
+                        cbm.CLOSE(READ_IO_CHANNEL)           ; close file because we already consumed first byte
                         void cbm.OPEN()         ; re-open the file
-                        void cbm.CHKIN(12)
+                        cbm.CLRCHN()            ; reset default i/o channels
                         return true
                     }
                 }
@@ -290,25 +312,26 @@ close_end:
     sub f_read(uword bufferpointer, uword num_bytes) -> uword {
         ; -- read from the currently open file, up to the given number of bytes.
         ;    returns the actual number of bytes read.  (checks for End-of-file and error conditions)
+        ;    NOTE: cannot be used to load into VRAM.  Use vload() or call cx16.MACPTR() yourself with the vera data register as address.
         if not iteration_in_progress or not num_bytes
             return 0
 
+        reset_read_channel()
         list_blocks = 0     ; we reuse this variable for the total number of bytes read
 
-        ; commander X16 supports fast block-read via macptr() kernal call
-        uword size
+        uword readsize
         while num_bytes {
-            size = 255
-            if num_bytes<size
-                size = num_bytes
-            size = cx16.macptr(lsb(size), bufferpointer, false)
+            readsize = 255
+            if num_bytes<readsize
+                readsize = num_bytes
+            readsize = cx16.MACPTR(lsb(readsize), bufferpointer, false)     ; fast block reads
             if_cs
-                goto byte_read_loop     ; macptr block read not supported, do fallback loop
-            list_blocks += size
-            bufferpointer += size
+                goto byte_read_loop     ; MACPTR block read not supported, do fallback loop
+            list_blocks += readsize
+            bufferpointer += readsize
             if msb(bufferpointer) == $c0
                 bufferpointer = mkword($a0, lsb(bufferpointer))  ; wrap over bank boundary
-            num_bytes -= size
+            num_bytes -= readsize
             if cbm.READST() & $40 {
                 f_close()       ; end of file, close it
                 break
@@ -316,7 +339,7 @@ close_end:
         }
         return list_blocks  ; number of bytes read
 
-byte_read_loop:         ; fallback if macptr() isn't supported on the device
+byte_read_loop:         ; fallback if MACPTR isn't supported on the device
         %asm {{
             lda  bufferpointer
             sta  m_in_buffer+1
@@ -347,9 +370,11 @@ m_in_buffer     sta  $ffff
     ; optimized for Commander X16 to use MACPTR block read kernal call
     sub f_read_all(uword bufferpointer) -> uword {
         ; -- read the full contents of the file, returns number of bytes read.
+        ;    NOTE: cannot be used to load into VRAM.  Use vload() or call cx16.MACPTR() yourself with the vera data register as address.
         if not iteration_in_progress
             return 0
 
+        reset_read_channel()
         uword total_read = 0
         while not cbm.READST() {
             cx16.r0 = f_read(bufferpointer, 256)
@@ -368,8 +393,7 @@ m_in_buffer     sta  $ffff
         %asm {{
             sta  P8ZP_SCRATCH_W1
             sty  P8ZP_SCRATCH_W1+1
-            ldx  #12
-            jsr  cbm.CHKIN              ; use channel 12 again for input
+            jsr  reset_read_channel
             ldy  #0
 _loop       jsr  cbm.CHRIN
             sta  (P8ZP_SCRATCH_W1),y
@@ -390,23 +414,41 @@ _end        rts
         ; -- end an iterative file loading session (close channels).
         if iteration_in_progress {
             cbm.CLRCHN()
-            cbm.CLOSE(12)
+            cbm.CLOSE(READ_IO_CHANNEL)
             iteration_in_progress = false
         }
     }
 
 
-    ; ----- iterative file writing functions (uses io channel 13) -----
+    ; ----- iterative file writing functions (uses write io channel) -----
 
-    sub f_open_w(uword filenameptr) -> bool {
-        ; -- open a file for iterative writing with f_write
+    sub f_open_w(str filename) -> bool {
+        ; -- Open a file for iterative writing with f_write
+        ;    WARNING: returns true if the open command was received by the device,
+        ;    but this can still mean the file wasn't successfully opened for writing!
+        ;    (for example, if it already exists). This is different than f_open()!
+        ;    To be 100% sure if this call was successful, you have to use status()
+        ;    and check the drive's status message!
+        return internal_f_open_w(filename, false)
+    }
+
+    sub f_open_w_seek(str filename) -> bool {
+        ; -- Open an existing file for iterative writing with f_write, and seeking with f_seek_w.
+        return internal_f_open_w(filename, true)
+    }
+
+    sub internal_f_open_w(str filename, bool open_for_seeks) -> bool {
         f_close_w()
-
-        cbm.SETNAM(string.length(filenameptr), filenameptr)
-        cbm.SETLFS(13, drivenumber, 1)
-        void cbm.OPEN()             ; open 13,8,1,"filename"
+        list_filename = filename
+        str modifier = ",s,?"
+        modifier[3] = 'w'
+        if open_for_seeks
+            modifier[3] = 'm'
+        cx16.r0L = string.append(list_filename, modifier)   ; secondary 13 requires a mode suffix to signal we're writing/modifying
+        cbm.SETNAM(cx16.r0L, list_filename)
+        cbm.SETLFS(WRITE_IO_CHANNEL, drivenumber, WRITE_IO_CHANNEL)
+        void cbm.OPEN()             ; open 13,8,13,"filename"
         if_cc {
-            cbm.CHKOUT(13)          ; use #13 as output channel
             return not cbm.READST()
         }
         f_close_w()
@@ -416,7 +458,22 @@ _end        rts
     sub f_write(uword bufferpointer, uword num_bytes) -> bool {
         ; -- write the given number of bytes to the currently open file
         if num_bytes!=0 {
-            cbm.CHKOUT(13)        ; use #13 as output channel again
+            reset_write_channel()
+            do {
+                cx16.r0 = cx16.MCIOUT(lsb(num_bytes), bufferpointer, false)     ; fast block writes
+                if_cs
+                    goto no_mciout
+                num_bytes -= cx16.r0
+                bufferpointer += cx16.r0
+                if msb(bufferpointer) == $c0
+                    bufferpointer = mkword($a0, lsb(bufferpointer))  ; wrap over bank boundary
+                if cbm.READST()!=0
+                    return false
+            } until num_bytes==0
+            return not cbm.READST()
+
+no_mciout:
+            ; the device doesn't support MCIOUT, use a normal per-byte write loop
             repeat num_bytes {
                 cbm.CHROUT(@(bufferpointer))
                 bufferpointer++
@@ -429,7 +486,7 @@ _end        rts
     sub f_close_w() {
         ; -- end an iterative file writing session (close channels).
         cbm.CLRCHN()
-        cbm.CLOSE(13)
+        cbm.CLOSE(WRITE_IO_CHANNEL)
     }
 
 
@@ -468,27 +525,26 @@ io_error:
 
 
     ; saves a block of memory to disk, including the default 2 byte prg header.
-    sub save(uword filenameptr, uword address, uword size) -> bool {
-        return internal_save_routine(filenameptr, address, size, false)
+    sub save(uword filenameptr, uword startaddress, uword savesize) -> bool {
+        return internal_save_routine(filenameptr, startaddress, savesize, false)
     }
 
     ; like save() but omits the 2 byte prg header.
-    sub save_raw(uword filenameptr, uword address, uword size) -> bool {
-        return internal_save_routine(filenameptr, address, size, true)
+    sub save_raw(uword filenameptr, uword startaddress, uword savesize) -> bool {
+        return internal_save_routine(filenameptr, startaddress, savesize, true)
     }
 
-    sub internal_save_routine(uword filenameptr, uword address, uword size, bool headerless) -> bool {
+    sub internal_save_routine(uword filenameptr, uword startaddress, uword savesize, bool headerless) -> bool {
         cbm.SETNAM(string.length(filenameptr), filenameptr)
         cbm.SETLFS(1, drivenumber, 0)
-        uword @shared end_address = address + size
+        uword @shared end_address = startaddress + savesize
         cx16.r0L = 0
 
         %asm {{
-            lda  address
+            lda  startaddress
             sta  P8ZP_SCRATCH_W1
-            lda  address+1
+            lda  startaddress+1
             sta  P8ZP_SCRATCH_W1+1
-            stx  P8ZP_SCRATCH_REG
             ldx  end_address
             ldy  end_address+1
             lda  headerless
@@ -499,16 +555,12 @@ io_error:
 +           lda  #<P8ZP_SCRATCH_W1
             jsr  cbm.SAVE
 +           php
-            ldx  P8ZP_SCRATCH_REG
             plp
         }}
 
         if_cc
             cx16.r0L = cbm.READST()==0
 
-        cbm.CLRCHN()
-        cbm.CLOSE(1)
-
         return cx16.r0L
     }
 
@@ -532,8 +584,8 @@ io_error:
     ; Identical to load(), but DOES INCLUDE the first 2 bytes in the file.
     ; No program header is assumed in the file. Everything is loaded.
     ; See comments on load() for more details.
-    sub load_raw(uword filenameptr, uword address) -> uword {
-        return internal_load_routine(filenameptr, address, true)
+    sub load_raw(uword filenameptr, uword startaddress) -> uword {
+        return internal_load_routine(filenameptr, startaddress, true)
     }
 
 
@@ -547,7 +599,6 @@ io_error:
             secondary |= %00000010  ; activate cx16 kernal headerless load support
         cbm.SETLFS(1, drivenumber, secondary)
         %asm {{
-            stx  P8ZP_SCRATCH_REG
             lda  #0
             ldx  address_override
             ldy  address_override+1
@@ -555,11 +606,9 @@ io_error:
             bcs  +
             stx  cx16.r1
             sty  cx16.r1+1
-+           ldx  P8ZP_SCRATCH_REG
++
         }}
 
-        cbm.CLRCHN()
-        cbm.CLOSE(1)
         return cx16.r1
     }
 
@@ -607,14 +656,13 @@ io_error:
         return $2000 * (cx16.getrambank() - startbank) + endaddress - startaddress
     }
 
-    asmsub vload(str name @R0, ubyte bank @A, uword address @R1) -> ubyte @A {
+    asmsub vload(str name @R0, ubyte bank @A, uword startaddress @R1) clobbers(X, Y) -> ubyte @A {
         ; -- like the basic command VLOAD "filename",drivenumber,bank,address
         ;    loads a file into Vera's video memory in the given bank:address, returns success in A
         ;    the file has to have the usual 2 byte header (which will be skipped)
         %asm {{
             clc
 internal_vload:
-            phx
             pha
             ldx  drivenumber
             bcc +
@@ -642,13 +690,12 @@ internal_vload:
     +       jsr  cbm.CLRCHN
             lda  #1
             jsr  cbm.CLOSE
-            plx
             lda  P8ZP_SCRATCH_B1
             rts
         }}
     }
 
-    asmsub vload_raw(str name @R0, ubyte bank @A, uword address @R1) -> ubyte @A {
+    asmsub vload_raw(str name @R0, ubyte bank @A, uword startaddress @R1) clobbers(X, Y) -> ubyte @A {
         ; -- like the basic command BVLOAD "filename",drivenumber,bank,address
         ;    loads a file into Vera's video memory in the given bank:address, returns success in A
         ;    the file is read fully including the first two bytes.
@@ -696,11 +743,11 @@ internal_vload:
         cx16.r12 = reversebuffer + MAX_PATH_LEN-1
         @(cx16.r12)=0
         cbm.SETNAM(3, "$=c")
-        cbm.SETLFS(12, diskio.drivenumber, 0)
+        cbm.SETLFS(READ_IO_CHANNEL, drivenumber, 0)
         void cbm.OPEN()          ; open 12,8,0,"$=c"
         if_cs
             goto io_error
-        void cbm.CHKIN(12)        ; use #12 as input channel
+        reset_read_channel()
         if_cs
             goto io_error
 
@@ -737,7 +784,7 @@ internal_vload:
 
 io_error:
         cbm.CLRCHN()
-        cbm.CLOSE(12)
+        cbm.CLOSE(READ_IO_CHANNEL)
         if status and status & $40 == 0
             return 0
         if @(cx16.r12)==0 {
@@ -770,7 +817,7 @@ io_error:
     sub f_seek(uword pos_hiword, uword pos_loword) {
         ; -- seek in the reading file opened with f_open, to the given 32-bits position
         ubyte[6] command = ['p',0,0,0,0,0]
-        command[1] = 12       ; f_open uses channel 12
+        command[1] = READ_IO_CHANNEL       ; f_open uses this secondary address
         command[2] = lsb(pos_loword)
         command[3] = msb(pos_loword)
         command[4] = lsb(pos_hiword)
@@ -780,18 +827,22 @@ io_error:
         cbm.SETLFS(15, drivenumber, 15)
         void cbm.OPEN()
         cbm.CLOSE(15)
+        reset_read_channel()       ; back to the read io channel
     }
 
 
-    ; NOTE: f_seek_w() doesn't work reliably right now. I only manage to corrupt the fat32 filesystem on the sdcard with it...
-;    sub f_seek_w(uword pos_hiword, uword pos_loword) {
-;        ; -- seek in the output file opened with f_open_w, to the given 32-bits position
-;        diskio.f_seek.command[1] = 13       ; f_open_w uses channel 13
-;        diskio.f_seek.command[2] = lsb(pos_loword)
-;        diskio.f_seek.command[3] = msb(pos_loword)
-;        diskio.f_seek.command[4] = lsb(pos_hiword)
-;        diskio.f_seek.command[5] = msb(pos_hiword)
-;        goto diskio.f_seek.send_command
-;    }
+    sub f_seek_w(uword pos_hiword, uword pos_loword) {
+        ; -- seek in the output file opened with f_open_w_seek, to the given 32-bits position
+        diskio.f_seek.command[1] = WRITE_IO_CHANNEL       ; f_open_w uses this secondary address
+        diskio.f_seek.command[2] = lsb(pos_loword)
+        diskio.f_seek.command[3] = msb(pos_loword)
+        diskio.f_seek.command[4] = lsb(pos_hiword)
+        diskio.f_seek.command[5] = msb(pos_hiword)
+        cbm.SETNAM(sizeof(diskio.f_seek.command), &diskio.f_seek.command)
+        cbm.SETLFS(15, drivenumber, 15)
+        void cbm.OPEN()
+        cbm.CLOSE(15)
+        reset_write_channel()    ; back to the write io channel
+    }
 
 }

compiler/res/prog8lib/cx16/emudbg.p8

@@ -0,0 +1,60 @@
+; Emulator debug interface.
+; Docs: https://github.com/X16Community/x16-emulator#emulator-io-registers
+
+emudbg {
+
+    const uword EMU_BASE = $9fb0
+
+    &ubyte EMU_DBG_HOTKEY_ENABLED = EMU_BASE + 0
+    &ubyte EMU_LOG_VIDEO          = EMU_BASE + 1
+    &ubyte EMU_LOG_KEYBOARD       = EMU_BASE + 2
+    &ubyte EMU_ECHO_MODE          = EMU_BASE + 3
+    &ubyte EMU_SAVE_ON_EXIT       = EMU_BASE + 4
+    &ubyte EMU_RECORD_GIF         = EMU_BASE + 5
+    &ubyte EMU_RECORD_WAV         = EMU_BASE + 6
+    &ubyte EMU_CMDKEYS_DISABLED   = EMU_BASE + 7
+    &ubyte EMU_CPUCLK_L           = EMU_BASE + 8     ; write: reset cpu clock to 0
+    &ubyte EMU_CPUCLK_M           = EMU_BASE + 9     ; write: outputs "User debug 1: $xx"
+    &ubyte EMU_CPUCLK_H           = EMU_BASE + 10    ; write: outputs "User debug 2: $xx"
+    &ubyte EMU_CPUCLK_U           = EMU_BASE + 11    ; write: outputs as character to console
+    ; 12 is unused for now
+    &ubyte EMU_KEYMAP             = EMU_BASE + 13
+    &ubyte EMU_EMU_DETECT1        = EMU_BASE + 14
+    &ubyte EMU_EMU_DETECT2        = EMU_BASE + 15
+
+    sub is_emulator() -> bool {
+        ; Test for emulator presence.
+        ; It is recommended to only use the debug registers if this returns true.
+        return EMU_EMU_DETECT1=='1' and EMU_EMU_DETECT2=='6'
+    }
+
+    sub console_write(str isoString) {
+        ; note: make sure the text is in Iso encoding.
+        if is_emulator() {
+            ubyte chr
+            repeat {
+                chr = @(isoString)
+                if_z
+                    break
+                EMU_CPUCLK_U = chr
+                isoString++
+            }
+        }
+    }
+
+    sub console_chrout(ubyte char) {
+        ; note: make sure the character is in Iso encoding.
+        if is_emulator()
+            EMU_CPUCLK_U = char
+    }
+
+    sub console_value1(ubyte value) {
+        if is_emulator()
+            EMU_CPUCLK_M = value
+    }
+
+    sub console_value2(ubyte value) {
+        if is_emulator()
+            EMU_CPUCLK_H = value
+    }
+}

compiler/res/prog8lib/cx16/floats.p8

@@ -8,8 +8,9 @@ floats {
 
     %option no_symbol_prefixing
 
-        const float  PI     = 3.141592653589793
-        const float  TWOPI  = 6.283185307179586
+        const float  π      = 3.141592653589793
+        const float  PI     = π
+        const float  TWOPI  = 2*π
 
 
 ; ---- ROM float functions (same as on C128 except base page) ----
@@ -28,7 +29,7 @@ romsub $fe00 = AYINT() clobbers(A,X,Y)          ; fac1-> signed word in 100-101
 romsub $fe03 = GIVAYF(ubyte lo @ Y, ubyte hi @ A) clobbers(A,X,Y)
 
 romsub $fe06 = FOUT() clobbers(X) -> uword @ AY             ; fac1 -> string, address returned in AY
-; romsub $fe09 = VAL_1() clobbers(A,X,Y)                      ; convert ASCII string to floating point [not yet implemented!!!]
+romsub $fe09 = VAL_1(uword string @XY, ubyte length @A) clobbers(A,X,Y) -> float @FAC1      ; convert ASCII string in XY and length in A, to floating point in FAC1. WARNING: not implemented in the ROM yet!
 
 ; GETADR: fac1 -> unsigned word in Y/A (might throw ILLEGAL QUANTITY) (result also in $14/15)
 ; (tip: use GETADRAY to get A/Y output; lo/hi switched to normal little endian order)
@@ -44,7 +45,7 @@ romsub $fe21 = FMULTT() clobbers(A,X,Y)                     ; fac1 *= fac2
 romsub $fe24 = FDIV(uword mflpt @ AY) clobbers(A,X,Y)       ; fac1 = mflpt in A/Y / fac1
 romsub $fe27 = FDIVT() clobbers(A,X,Y)                      ; fac1 = fac2/fac1  mind the order of the operands
 romsub $fe2a = LOG() clobbers(A,X,Y)                        ; fac1 = LN(fac1)  (natural log)
-romsub $fe2d = INT() clobbers(A,X,Y)                        ; INT() truncates, use FADDH first to round instead of trunc
+romsub $fe2d = INT() clobbers(A,X,Y)                        ; INT() truncates, use ROUND or FADDH first to round instead of trunc
 romsub $fe30 = SQR() clobbers(A,X,Y)                        ; fac1 = SQRT(fac1)
 romsub $fe33 = NEGOP() clobbers(A)                          ; switch the sign of fac1 (fac1 = -fac1)
 romsub $fe36 = FPWR(uword mflpt @ AY) clobbers(A,X,Y)       ; fac1 = fac2 ** float in A/Y
@@ -71,10 +72,10 @@ romsub $fe6c = MOVAF() clobbers(A,X)                        ; copy fac1 to fac2
 ; X16 additions
 romsub $fe6f = FADDH() clobbers(A,X,Y)                      ; fac1 += 0.5, for rounding- call this before INT
 romsub $fe72 = ZEROFC() clobbers(A,X,Y)                     ; fac1 = 0
-romsub $fe75 = NORMAL() clobbers(A,X,Y)                     ; normalize fac1 (?)
-romsub $fe78 = NEGFAC() clobbers(A)                         ; switch the sign of fac1 (fac1 = -fac1) (juse use NEGOP() instead!)
+romsub $fe75 = NORMAL() clobbers(A,X,Y)                     ; normalize fac1
+romsub $fe78 = NEGFAC() clobbers(A)                         ; switch the sign of fac1 (fac1 = -fac1) (doesn't work, juse use NEGOP() instead!)
 romsub $fe7b = MUL10() clobbers(A,X,Y)                      ; fac1 *= 10
-romsub $fe7e = DIV10() clobbers(A,X,Y)                      ; fac1 /= 10 , CAUTION: result is always positive!
+romsub $fe7e = DIV10() clobbers(A,X,Y)                      ; fac1 /= 10 , CAUTION: result is always positive! Have to restore sign manually!
 romsub $fe81 = MOVEF() clobbers(A,X)                        ; copy fac1 to fac2
 romsub $fe84 = SGN() clobbers(A,X,Y)                        ; fac1 = SGN(fac1), result of SIGN (-1, 0 or 1)
 romsub $fe87 = FLOAT() clobbers(A,X,Y)                      ; FAC = (s8).A
@@ -99,14 +100,11 @@ asmsub  FREADSA  (byte value @A) clobbers(A,X,Y) {
 asmsub  GIVUAYFAY  (uword value @ AY) clobbers(A,X,Y)  {
 	; ---- unsigned 16 bit word in A/Y (lo/hi) to fac1
 	%asm {{
-	phx
 	sty  $c4        ; facmo     ($64 on c128)
 	sta  $c5        ; facmo+1   ($65 on c128)
 	ldx  #$90
 	sec
-	jsr  FLOATC
-	plx
-	rts
+	jmp  FLOATC
 	}}
 }
 
@@ -139,16 +137,56 @@ asmsub  FREADUY (ubyte value @Y) {
     }}
 }
 
+asmsub parse_f(str value @AY) -> float @FAC1 {
+    ; -- parse a string value of a number to float in FAC1
+    ;    warning: on older <R47 kernals it uses an internal BASIC routine that is ROM version dependent,
+    ;    ($deb6 is inside the routine for VAL at $deb3)  See basic.sym from x16-rom
+    ;    TODO once VAL_1 is merged into the kernal properly, remove all the workarounds here
+    %asm {{
+        ldx  VAL_1
+        cpx  #$4c       ; is there an implementation in VAL_1? (test for JMP)
+        bne  +          ; no, do it ourselves
+        pha             ; yes, count the length and call rom VAL_1.
+        phy
+        jsr  prog8_lib.strlen
+        tya
+        ply
+        plx
+        jmp  VAL_1
++       sta  $a9    ; 'index' variable
+        sty  $aa
+        jsr  prog8_lib.strlen
+        lda  $deb6
+        cmp  #$d0   ; sanity check for kernal routine correct
+        bne  +
+        tya
+        jmp  $deb6   ; kernal version dependent...
++       ; print error message if routine is borked in kernal, and exit program
+        ldy  #0
+-       lda  _msg,y
+        beq  +
+        jsr  cbm.CHROUT
+        iny
+        bne  -
++       jmp  sys.exit
+
+_msg    .text 13,"?val kaputt",13,0
+    }}
+}
+
 
 &uword AYINT_facmo = $c6      ; $c6/$c7 contain result of AYINT
 
 sub rndf() -> float {
     %asm {{
-        phx
         lda  #1
-        jsr  RND_0
-        plx
-        rts
+        jmp  RND_0
+    }}
+}
+
+asmsub normalize(float value @FAC1) -> float @ FAC1 {
+    %asm {{
+        jmp  floats.NORMAL
     }}
 }