version 7.2

# Conflicts:
#	compiler/res/version.txt

.gitignore

@@ -26,8 +26,9 @@ parser.out
 parsetab.py
 .pytest_cache/
 .attach_pid*
+compiler/lib/
 
 .gradle
 /prog8compiler.jar
 sd*.img
-
+*.d64

.idea/codeInsightSettings.xml

@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="JavaProjectCodeInsightSettings">
+    <excluded-names>
+      <name>kotlin.Result</name>
+    </excluded-names>
+  </component>
+</project>

.idea/compiler.xml

@@ -0,0 +1,7 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="CompilerConfiguration">
+    <option name="BUILD_PROCESS_HEAP_SIZE" value="1200" />
+    <bytecodeTargetLevel target="11" />
+  </component>
+</project>

.idea/inspectionProfiles/Project_Default.xml

@@ -3,14 +3,11 @@
     <option name="myName" value="Project Default" />
     <inspection_tool class="DuplicatedCode" enabled="true" level="WEAK WARNING" enabled_by_default="true">
       <Languages>
-        <language minSize="100" isEnabled="false" name="JavaScript" />
-        <language isEnabled="false" name="Groovy" />
-        <language isEnabled="false" name="Style Sheets" />
         <language minSize="70" name="Kotlin" />
-        <language isEnabled="false" name="TypeScript" />
-        <language isEnabled="false" name="ActionScript" />
+        <language isEnabled="false" name="Groovy" />
       </Languages>
     </inspection_tool>
+    <inspection_tool class="PyInterpreterInspection" enabled="false" level="WARNING" enabled_by_default="false" />
     <inspection_tool class="SpellCheckingInspection" enabled="true" level="TYPO" enabled_by_default="true">
       <option name="processCode" value="false" />
       <option name="processLiterals" value="true" />

.idea/kotlinc.xml

@@ -1,6 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<project version="4">
-  <component name="Kotlin2JvmCompilerArguments">
-    <option name="jvmTarget" value="1.8" />
-  </component>
-</project>

.idea/libraries/antlr_4_9_complete.xml

@@ -1,9 +0,0 @@
-<component name="libraryTable">
-  <library name="antlr-4.9-complete">
-    <CLASSES>
-      <root url="jar://$PROJECT_DIR$/parser/antlr/lib/antlr-4.9-complete.jar!/" />
-    </CLASSES>
-    <JAVADOC />
-    <SOURCES />
-  </library>
-</component>

.idea/libraries/antlr_antlr4.xml

@@ -0,0 +1,19 @@
+<component name="libraryTable">
+  <library name="antlr.antlr4" type="repository">
+    <properties maven-id="org.antlr:antlr4:4.9.2">
+      <exclude>
+        <dependency maven-id="com.ibm.icu:icu4j" />
+      </exclude>
+    </properties>
+    <CLASSES>
+      <root url="jar://$MAVEN_REPOSITORY$/org/antlr/antlr4/4.9.2/antlr4-4.9.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/antlr/antlr4-runtime/4.9.2/antlr4-runtime-4.9.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/antlr/antlr-runtime/3.5.2/antlr-runtime-3.5.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/antlr/ST4/4.3/ST4-4.3.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/abego/treelayout/org.abego.treelayout.core/1.0.3/org.abego.treelayout.core-1.0.3.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/glassfish/javax.json/1.0.4/javax.json-1.0.4.jar!/" />
+    </CLASSES>
+    <JAVADOC />
+    <SOURCES />
+  </library>
+</component>

.idea/libraries/antlr_runtime_4_9.xml

@@ -1,9 +0,0 @@
-<component name="libraryTable">
-  <library name="antlr-runtime-4.9">
-    <CLASSES>
-      <root url="jar://$PROJECT_DIR$/parser/antlr/lib/antlr-runtime-4.9.jar!/" />
-    </CLASSES>
-    <JAVADOC />
-    <SOURCES />
-  </library>
-</component>

.idea/libraries/dbus_java_3_2_4.xml

@@ -1,9 +0,0 @@
-<component name="libraryTable">
-  <library name="dbus-java-3.2.4">
-    <CLASSES>
-      <root url="jar://$PROJECT_DIR$/dbusCompilerService/lib/dbus-java-3.2.4.jar!/" />
-    </CLASSES>
-    <JAVADOC />
-    <SOURCES />
-  </library>
-</component>

.idea/libraries/github_hypfvieh_dbus_java.xml

@@ -0,0 +1,25 @@
+<component name="libraryTable">
+  <library name="github.hypfvieh.dbus.java" type="repository">
+    <properties maven-id="com.github.hypfvieh:dbus-java:3.3.1" />
+    <CLASSES>
+      <root url="jar://$MAVEN_REPOSITORY$/com/github/hypfvieh/dbus-java/3.3.1/dbus-java-3.3.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/com/github/jnr/jnr-unixsocket/0.38.6/jnr-unixsocket-0.38.6.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/com/github/jnr/jnr-ffi/2.2.2/jnr-ffi-2.2.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/com/github/jnr/jffi/1.3.1/jffi-1.3.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/com/github/jnr/jffi/1.3.1/jffi-1.3.1-native.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/ow2/asm/asm/9.1/asm-9.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/ow2/asm/asm-commons/9.1/asm-commons-9.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/ow2/asm/asm-analysis/9.1/asm-analysis-9.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/ow2/asm/asm-tree/9.1/asm-tree-9.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/ow2/asm/asm-util/9.1/asm-util-9.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/com/github/jnr/jnr-a64asm/1.0.0/jnr-a64asm-1.0.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/com/github/jnr/jnr-x86asm/1.0.2/jnr-x86asm-1.0.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/com/github/jnr/jnr-constants/0.10.1/jnr-constants-0.10.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/com/github/jnr/jnr-enxio/0.32.4/jnr-enxio-0.32.4.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/com/github/jnr/jnr-posix/3.1.5/jnr-posix-3.1.5.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/slf4j/slf4j-api/1.7.30/slf4j-api-1.7.30.jar!/" />
+    </CLASSES>
+    <JAVADOC />
+    <SOURCES />
+  </library>
+</component>

.idea/libraries/glassfish_javax_json.xml

@@ -0,0 +1,10 @@
+<component name="libraryTable">
+  <library name="glassfish.javax.json" type="repository">
+    <properties include-transitive-deps="false" maven-id="org.glassfish:javax.json:1.1.4" />
+    <CLASSES>
+      <root url="jar://$MAVEN_REPOSITORY$/org/glassfish/javax.json/1.1.4/javax.json-1.1.4.jar!/" />
+    </CLASSES>
+    <JAVADOC />
+    <SOURCES />
+  </library>
+</component>

.idea/libraries/hamcrest.xml

@@ -0,0 +1,10 @@
+<component name="libraryTable">
+  <library name="hamcrest" type="repository">
+    <properties maven-id="org.hamcrest:hamcrest:2.2" />
+    <CLASSES>
+      <root url="jar://$MAVEN_REPOSITORY$/org/hamcrest/hamcrest/2.2/hamcrest-2.2.jar!/" />
+    </CLASSES>
+    <JAVADOC />
+    <SOURCES />
+  </library>
+</component>

.idea/libraries/javax_json_api_1_1_4.xml

@@ -1,10 +0,0 @@
-<component name="libraryTable">
-  <library name="javax.json-api-1.1.4">
-    <CLASSES>
-      <root url="jar://$PROJECT_DIR$/httpCompilerService/lib/javax.json-api-1.1.4.jar!/" />
-      <root url="jar://$PROJECT_DIR$/httpCompilerService/lib/javax.json-1.1.4.jar!/" />
-    </CLASSES>
-    <JAVADOC />
-    <SOURCES />
-  </library>
-</component>

.idea/libraries/jetbrains_kotlinx_cli_jvm.xml

@@ -0,0 +1,10 @@
+<component name="libraryTable">
+  <library name="jetbrains.kotlinx.cli.jvm" type="repository">
+    <properties include-transitive-deps="false" maven-id="org.jetbrains.kotlinx:kotlinx-cli-jvm:0.3.3" />
+    <CLASSES>
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-cli-jvm/0.3.3/kotlinx-cli-jvm-0.3.3.jar!/" />
+    </CLASSES>
+    <JAVADOC />
+    <SOURCES />
+  </library>
+</component>

.idea/libraries/junit_jupiter.xml

@@ -0,0 +1,17 @@
+<component name="libraryTable">
+  <library name="junit.jupiter" type="repository">
+    <properties maven-id="org.junit.jupiter:junit-jupiter:5.7.2" />
+    <CLASSES>
+      <root url="jar://$MAVEN_REPOSITORY$/org/junit/jupiter/junit-jupiter/5.7.2/junit-jupiter-5.7.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/junit/jupiter/junit-jupiter-api/5.7.2/junit-jupiter-api-5.7.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/apiguardian/apiguardian-api/1.1.0/apiguardian-api-1.1.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/opentest4j/opentest4j/1.2.0/opentest4j-1.2.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/junit/platform/junit-platform-commons/1.7.2/junit-platform-commons-1.7.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/junit/jupiter/junit-jupiter-params/5.7.2/junit-jupiter-params-5.7.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/junit/jupiter/junit-jupiter-engine/5.7.2/junit-jupiter-engine-5.7.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/junit/platform/junit-platform-engine/1.7.2/junit-platform-engine-1.7.2.jar!/" />
+    </CLASSES>
+    <JAVADOC />
+    <SOURCES />
+  </library>
+</component>

.idea/libraries/kotlinx_cli_jvm.xml

@@ -1,9 +0,0 @@
-<component name="libraryTable">
-  <library name="kotlinx-cli-jvm">
-    <CLASSES>
-      <root url="jar://$PROJECT_DIR$/compiler/lib/kotlinx-cli-jvm-0.3.1.jar!/" />
-    </CLASSES>
-    <JAVADOC />
-    <SOURCES />
-  </library>
-</component>

.idea/libraries/michael_bull_kotlin_result_jvm.xml

@@ -0,0 +1,15 @@
+<component name="libraryTable">
+  <library name="michael.bull.kotlin.result.jvm" type="repository">
+    <properties maven-id="com.michael-bull.kotlin-result:kotlin-result-jvm:1.1.12" />
+    <CLASSES>
+      <root url="jar://$MAVEN_REPOSITORY$/com/michael-bull/kotlin-result/kotlin-result-jvm/1.1.12/kotlin-result-jvm-1.1.12.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk8/1.5.10/kotlin-stdlib-jdk8-1.5.10.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/1.5.10/kotlin-stdlib-1.5.10.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-jdk7/1.5.10/kotlin-stdlib-jdk7-1.5.10.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-common/1.5.10/kotlin-stdlib-common-1.5.10.jar!/" />
+    </CLASSES>
+    <JAVADOC />
+    <SOURCES />
+  </library>
+</component>

.idea/libraries/slf4j_api_1_7_30.xml

@@ -1,10 +0,0 @@
-<component name="libraryTable">
-  <library name="slf4j-api-1.7.30">
-    <CLASSES>
-      <root url="jar://$PROJECT_DIR$/httpCompilerService/lib/slf4j-api-1.7.30.jar!/" />
-      <root url="jar://$PROJECT_DIR$/httpCompilerService/lib/slf4j-simple-1.7.30.jar!/" />
-    </CLASSES>
-    <JAVADOC />
-    <SOURCES />
-  </library>
-</component>

.idea/libraries/slf4j_simple.xml

@@ -0,0 +1,11 @@
+<component name="libraryTable">
+  <library name="slf4j.simple" type="repository">
+    <properties maven-id="org.slf4j:slf4j-simple:1.7.30" />
+    <CLASSES>
+      <root url="jar://$MAVEN_REPOSITORY$/org/slf4j/slf4j-simple/1.7.30/slf4j-simple-1.7.30.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/slf4j/slf4j-api/1.7.30/slf4j-api-1.7.30.jar!/" />
+    </CLASSES>
+    <JAVADOC />
+    <SOURCES />
+  </library>
+</component>

.idea/libraries/takes.xml

@@ -0,0 +1,13 @@
+<component name="libraryTable">
+  <library name="takes" type="repository">
+    <properties maven-id="org.takes:takes:1.19" />
+    <CLASSES>
+      <root url="jar://$MAVEN_REPOSITORY$/org/takes/takes/1.19/takes-1.19.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/cactoos/cactoos/0.42/cactoos-0.42.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/apache/commons/commons-text/1.4/commons-text-1.4.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/apache/commons/commons-lang3/3.7/commons-lang3-3.7.jar!/" />
+    </CLASSES>
+    <JAVADOC />
+    <SOURCES />
+  </library>
+</component>

.idea/libraries/takes_http.xml

@@ -1,12 +0,0 @@
-<component name="libraryTable">
-  <library name="takes-http">
-    <CLASSES>
-      <root url="jar://$PROJECT_DIR$/httpCompilerService/lib/cactoos-0.42.jar!/" />
-      <root url="jar://$PROJECT_DIR$/httpCompilerService/lib/commons-lang3-3.7.jar!/" />
-      <root url="jar://$PROJECT_DIR$/httpCompilerService/lib/commons-text-1.4.jar!/" />
-      <root url="jar://$PROJECT_DIR$/httpCompilerService/lib/takes-1.19.jar!/" />
-    </CLASSES>
-    <JAVADOC />
-    <SOURCES />
-  </library>
-</component>

.idea/libraries/unittest_libs.xml

@@ -1,10 +0,0 @@
-<component name="libraryTable">
-  <library name="unittest-libs">
-    <CLASSES>
-      <root url="file://$PROJECT_DIR$/compiler/lib" />
-    </CLASSES>
-    <JAVADOC />
-    <SOURCES />
-    <jarDirectory url="file://$PROJECT_DIR$/compiler/lib" recursive="false" />
-  </library>
-</component>

.idea/misc.xml

@@ -4,7 +4,7 @@
     <option name="perGrammarGenerationSettings">
       <list>
         <PerGrammarGenerationSettings>
-          <option name="fileName" value="$PROJECT_DIR$/parser/antlr/prog8.g4" />
+          <option name="fileName" value="$PROJECT_DIR$/parser/antlr/Prog8ANTLR.g4" />
           <option name="autoGen" value="true" />
           <option name="outputDir" value="$PROJECT_DIR$/parser/src/prog8/parser" />
           <option name="libDir" value="" />
@@ -16,7 +16,7 @@
       </list>
     </option>
   </component>
-  <component name="ProjectRootManager" version="2" languageLevel="JDK_11" default="false" project-jdk-name="Kotlin SDK" project-jdk-type="KotlinSDK">
+  <component name="ProjectRootManager" version="2" languageLevel="JDK_11" project-jdk-name="Kotlin SDK" project-jdk-type="KotlinSDK">
     <output url="file://$PROJECT_DIR$/out" />
   </component>
-</project>
+</project>

.idea/modules.xml

@@ -2,7 +2,11 @@
 <project version="4">
   <component name="ProjectModuleManager">
     <modules>
+      <module fileurl="file://$PROJECT_DIR$/codeGeneration/codeGeneration.iml" filepath="$PROJECT_DIR$/codeGeneration/codeGeneration.iml" />
+      <module fileurl="file://$PROJECT_DIR$/codeOptimizers/codeOptimizers.iml" filepath="$PROJECT_DIR$/codeOptimizers/codeOptimizers.iml" />
       <module fileurl="file://$PROJECT_DIR$/compiler/compiler.iml" filepath="$PROJECT_DIR$/compiler/compiler.iml" />
+      <module fileurl="file://$PROJECT_DIR$/compilerAst/compilerAst.iml" filepath="$PROJECT_DIR$/compilerAst/compilerAst.iml" />
+      <module fileurl="file://$PROJECT_DIR$/compilerInterfaces/compilerInterfaces.iml" filepath="$PROJECT_DIR$/compilerInterfaces/compilerInterfaces.iml" />
       <module fileurl="file://$PROJECT_DIR$/dbusCompilerService/dbusCompilerService.iml" filepath="$PROJECT_DIR$/dbusCompilerService/dbusCompilerService.iml" />
       <module fileurl="file://$PROJECT_DIR$/docs/docs.iml" filepath="$PROJECT_DIR$/docs/docs.iml" />
       <module fileurl="file://$PROJECT_DIR$/examples/examples.iml" filepath="$PROJECT_DIR$/examples/examples.iml" />

.travis.yml

@@ -1,11 +0,0 @@
-language: java
-sudo: false
-# jdk: openjdk8
-# dist: xenial
-
-before_install:
-  - chmod +x ./gradlew
-
-script:
-  - ./gradlew test
-

CompilerDevelopment.md

@@ -0,0 +1,32 @@
+#### Just a few remarks upfront:
+* There is the (gradle/IDEA) module `parser`: that's the parser generated by ANTLR4, in Java. The only file to be edited here is the grammar, `prog8.g4`.
+* Then we have the module `compilerAst` - in Kotlin - which uses `parser` and adds AST nodes. Here we put our additions to the generated thing, *including any tests of the parsing stage*.
+  - the name is a bit misleading, as this module isn't (or, resp. shouldn't be; see below) about *compiling*, only the parsing stage
+  - also, the tree that comes out isn't much of an *abstraction*, but rather still more or less a parse tree (this might very well change).
+  - **However, let's not *yet* rename the module.** We'll find a good name during refactoring.
+
+#### Problems with `compilerAst`:
+* `ModuleImporter.kt`, doing (Prog8-) module resolution. That's not the parser's job.
+* `ParsingFailedError` (in `ModuleParsing.kt`): this exception (it is actually *not* a `java.lang.Error`...) is thrown in a number of places, where other exceptions would make more sense. For example: not finding a file should just yield a `NoSuchFileException`, not this one. The other problem with it is that it does not provide any additional information about the source of parsing error, in particular a `Position`.
+* During parsing, character literals are turned into UBYTEs (since there is no basic type e.g. CHAR). That's bad because it depends on a specific character encoding (`IStringEncoding` in `compilerAst/src/prog8/ast/AstToplevel.kt`) of/for some target platform. Note that *strings* are indeed encoded later, in the `compiler` module.
+* The same argument applies to `IMemSizer`, and - not entirely sure about that - `IBuiltinFunctions`.
+
+#### Steps to take, in conceptual (!) order:
+1. introduce an abstraction `SourceCode` that encapsulates the origin and actual loading of Prog8 source code
+   - from the local file system (use case: user programs)
+   - from resources (prog8lib)
+   - from plain strings (for testing)
+2. add subclass `ParseError : ParsingFailedError` which adds information about the *source of parsing error* (`SourceCode` and `Position`). We cannot just replace `ParsingFailedError`  right away because it is so widely used (even in the `compiler` module). Therefore we'll just subclass for the time being, add more and more tests requiring the new one to be thrown (or, resp., NOT to be thrown), and gradually transition.
+3. introduce a minimal interface to the outside, input: `SourceCode`, output: a tree with a `Module` node as the root
+   - this will be the Kotlin singleton `Prog8Parser` with the main method `parseModule`
+   - plus, optionally, method's for registering/unregistering a listener with the parser
+   - the *only* exception ever thrown / reported to listeners (TBD) will be `ParseError`
+   - anything related to the lexer, error strategies, character/token streams is hidden from the outside
+   - to make a clear distinction between the *generated* parser (and lexer) vs. `Prog8Parser`, and to discourage directly using the generated stuff, we'll rename the existing `prog8Parser`/`prog8Lexer` to `Prog8ANTLRParser` and `Prog8ANTLRLexer` and move them to package `prog8.parser.generated`
+4. introduce AST node `CharLiteral` and keep them until after identifier resolution and type checking; insert there an AST transformation step that turns them in UBYTE constants (literals)
+5. remove uses of `IStringEncoding` from module `compilerAst` - none should be necessary anymore
+6. move `IStringEncoding` to module `compiler`
+7. same with `ModuleImporter`, then rewrite that (addressing #46)
+8. refactor AST nodes and grammar: less generated parse tree nodes (`XyzContext`), less intermediary stuff (private classes in `Antrl2Kotlin.kt`), more compact code. Also: nicer names such as simply `StringLiteral` instead of `StringLiteralValue`
+9. re-think `IStringEncoding` to address #38
+

LICENSE

@@ -1,3 +1,10 @@
+
+This sofware license is for Prog8 the compiler + associated libraries.
+The software generated by running the compiler is excluded from this.
+
+
+
+
                     GNU GENERAL PUBLIC LICENSE
                        Version 3, 29 June 2007
 

README.md

@@ -1,5 +1,3 @@
-[![saythanks](https://img.shields.io/badge/say-thanks-ff69b4.svg)](https://saythanks.io/to/irmen)
-[![Build Status](https://travis-ci.org/irmen/prog8.svg?branch=master)](https://travis-ci.org/irmen/prog8)
 [![Documentation](https://readthedocs.org/projects/prog8/badge/?version=latest)](https://prog8.readthedocs.io/)
 
 Prog8 - Structured Programming Language for 8-bit 6502/65c02 microprocessors
@@ -7,9 +5,6 @@ Prog8 - Structured Programming Language for 8-bit 6502/65c02 microprocessors
 
 *Written by Irmen de Jong (irmen@razorvine.net)*
 
-*Software license: GNU GPL 3.0, see file LICENSE*
-
-
 This is a structured programming language for the 8-bit 6502/6510/65c02 microprocessor from the late 1970's and 1980's
 as used in many home computers from that era. It is a medium to low level programming language,
 which aims to provide many conveniences over raw assembly code (even when using a macro assembler).
@@ -19,27 +14,36 @@ Documentation
 Full documentation (syntax reference, how to use the language and the compiler, etc.) can be found at:
 https://prog8.readthedocs.io/
 
+Software license
+----------------
+GNU GPL 3.0, see file LICENSE
+
+- prog8 (the compiler + libraries) is licensed under GNU GPL 3.0
+- *exception:* the resulting files created by running the compiler are free to use in whatever way desired.
+
 
 What does Prog8 provide?
 ------------------------
 
-- big reduction of source code length over raw assembly
+- reduction of source code length over raw assembly
+- fast execution speed due to compilation to native assembly code. It's possible to write certain raster interrupt 'demoscene' effects purely in Prog8.
 - modularity, symbol scoping, subroutines
 - various data types other than just bytes (16-bit words, floats, strings)
-- automatic variable allocations, automatic string and array variables and string sharing
-- subroutines with an input- and output parameter signature
-- no stack frame allocations because parameters and local variables are automatically allocated statically
-- constant folding in expressions and other high-level program optimizations
+- floating point math is supported if the target system provides floating point library routines (C64 and Cx16 both do)
+- strings can contain escaped characters but also many symbols directly if they have a petscii equivalent, such as "♠♥♣♦π▚●○╳". Characters like ^, _, \, {, } and | are also accepted and converted to the closest petscii equivalents.
+- automatic static variable allocations, automatic string and array variables and string sharing
+- subroutines with input parameters and result values
+- high-level program optimizations
+- small program boilerplate/compilersupport overhead
+- programs can be run multiple times without reloading because of automatic variable (re)initializations.
 - conditional branches
-- floating point operations  (requires the C64 Basic ROM routines for this)
 - 'when' statement to provide a concise jump table alternative to if/elseif chains
-- structs to group together sets of variables and manipulate them at once
 - many built-in functions such as ``sin``, ``cos``, ``rnd``, ``abs``, ``min``, ``max``, ``sqrt``, ``msb``, ``rol``, ``ror``, ``swap``, ``sort`` and ``reverse``
 - various powerful built-in libraries to do I/O, number conversions, graphics and more  
 - convenience abstractions for low level aspects such as ZeroPage handling, program startup, explicit memory addresses
-- fast execution speed due to compilation to native assembly code
 - inline assembly allows you to have full control when every cycle or byte matters
-- supports the sixteen 'virtual' 16-bit registers R0 .. R15 from the Commander X16, and provides them also on the C64.
+- supports the sixteen 'virtual' 16-bit registers R0 - R15 from the Commander X16, and provides them also on the C64.
+- encode strings and characters into petscii or screencodes as desired (C64/Cx16)
 
 *Rapid edit-compile-run-debug cycle:*
 
@@ -52,7 +56,7 @@ What does Prog8 provide?
 
 - "c64": Commodore-64  (6510 CPU = almost a 6502)
 - "cx16": [CommanderX16](https://www.commanderx16.com)  (65c02 CPU)
-- If you only use standard kernel and prog8 library routines, it is possible to compile the *exact same program* for both machines (just change the compiler target flag)!
+- If you only use standard kernal and prog8 library routines, it is possible to compile the *exact same program* for both machines (just change the compiler target flag)!
 
 
 

build.gradle

@@ -0,0 +1,10 @@
+plugins {
+    id "org.jetbrains.kotlin.jvm" version "$kotlinVersion" apply false
+}
+
+allprojects {
+    repositories {
+        mavenLocal()
+        mavenCentral()
+    }
+}

codeGeneration/build.gradle

@@ -0,0 +1,56 @@
+
+plugins {
+    id 'java'
+    id 'application'
+    id "org.jetbrains.kotlin.jvm"
+}
+
+java {
+    toolchain {
+        languageVersion = JavaLanguageVersion.of(javaVersion)
+    }
+}
+
+dependencies {
+    implementation project(':compilerInterfaces')
+    implementation project(':compilerAst')
+    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8"
+    // implementation "org.jetbrains.kotlin:kotlin-reflect"
+    implementation "com.michael-bull.kotlin-result:kotlin-result-jvm:1.1.12"
+
+    testImplementation "org.jetbrains.kotlin:kotlin-test-junit5"
+    testImplementation 'org.junit.jupiter:junit-jupiter-api:5.7.2'
+    testImplementation 'org.hamcrest:hamcrest:2.2'
+    testRuntimeOnly 'org.junit.jupiter:junit-jupiter-engine:5.7.2'
+
+}
+
+sourceSets {
+    main {
+        java {
+            srcDirs = ["${project.projectDir}/src"]
+        }
+        resources {
+            srcDirs = ["${project.projectDir}/res"]
+        }
+    }
+    test {
+        java {
+            srcDirs = ["${project.projectDir}/test"]
+        }
+    }
+}
+
+
+test {
+    // Enable JUnit 5 (Gradle 4.6+).
+    useJUnitPlatform()
+
+    // Always run tests, even when nothing changed.
+    dependsOn 'cleanTest'
+
+    // Show test results.
+    testLogging {
+        events "skipped", "failed"
+    }
+}

codeGeneration/codeGeneration.iml

@@ -0,0 +1,19 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<module type="JAVA_MODULE" version="4">
+  <component name="NewModuleRootManager" inherit-compiler-output="true">
+    <exclude-output />
+    <content url="file://$MODULE_DIR$">
+      <sourceFolder url="file://$MODULE_DIR$/src" isTestSource="false" />
+      <sourceFolder url="file://$MODULE_DIR$/test" isTestSource="true" />
+      <excludeFolder url="file://$MODULE_DIR$/build" />
+    </content>
+    <orderEntry type="jdk" jdkName="openjdk-11" jdkType="JavaSDK" />
+    <orderEntry type="sourceFolder" forTests="false" />
+    <orderEntry type="library" name="KotlinJavaRuntime" level="project" />
+    <orderEntry type="library" name="michael.bull.kotlin.result.jvm" level="project" />
+    <orderEntry type="module" module-name="compilerInterfaces" />
+    <orderEntry type="module" module-name="compilerAst" />
+    <orderEntry type="library" scope="TEST" name="hamcrest" level="project" />
+    <orderEntry type="library" name="junit.jupiter" level="project" />
+  </component>
+</module>

codeGeneration/src/prog8/compiler/target/AssemblyError.kt

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

codeGeneration/src/prog8/compiler/target/C64Target.kt

@@ -0,0 +1,35 @@
+package prog8.compiler.target
+
+import com.github.michaelbull.result.fold
+import prog8.ast.base.ByteDatatypes
+import prog8.ast.base.DataType
+import prog8.ast.base.PassByReferenceDatatypes
+import prog8.ast.base.WordDatatypes
+import prog8.compiler.target.c64.C64MachineDefinition
+import prog8.compiler.target.cbm.Petscii
+import prog8.compilerinterface.ICompilationTarget
+
+
+object C64Target: ICompilationTarget {
+    override val name = "c64"
+    override val machine = C64MachineDefinition
+    override fun encodeString(str: String, altEncoding: Boolean): List<Short> {
+        val coded = if (altEncoding) Petscii.encodeScreencode(str, true) else Petscii.encodePetscii(str, true)
+        return coded.fold(
+            failure = { throw it },
+            success = { it }
+        )
+    }
+    override fun decodeString(bytes: List<Short>, altEncoding: Boolean) =
+        if (altEncoding) Petscii.decodeScreencode(bytes, true) else Petscii.decodePetscii(bytes, true)
+
+    override fun memorySize(dt: DataType): Int {
+        return when(dt) {
+            in ByteDatatypes -> 1
+            in WordDatatypes -> 2
+            DataType.FLOAT -> machine.FLOAT_MEM_SIZE
+            in PassByReferenceDatatypes -> machine.POINTER_MEM_SIZE
+            else -> -9999999
+        }
+    }
+}

codeGeneration/src/prog8/compiler/target/Cx16Target.kt

@@ -0,0 +1,36 @@
+package prog8.compiler.target
+
+import com.github.michaelbull.result.fold
+import prog8.ast.base.ByteDatatypes
+import prog8.ast.base.DataType
+import prog8.ast.base.PassByReferenceDatatypes
+import prog8.ast.base.WordDatatypes
+import prog8.compiler.target.cbm.Petscii
+import prog8.compiler.target.cx16.CX16MachineDefinition
+import prog8.compilerinterface.ICompilationTarget
+
+
+object Cx16Target: ICompilationTarget {
+    override val name = "cx16"
+    override val machine = CX16MachineDefinition
+    override fun encodeString(str: String, altEncoding: Boolean): List<Short> {
+        val coded= if (altEncoding) Petscii.encodeScreencode(str, true) else Petscii.encodePetscii(str, true)
+        return coded.fold(
+            failure = { throw it },
+            success = { it }
+        )
+    }
+    override fun decodeString(bytes: List<Short>, altEncoding: Boolean) =
+        if (altEncoding) Petscii.decodeScreencode(bytes, true) else Petscii.decodePetscii(bytes, true)
+
+    override fun memorySize(dt: DataType): Int {
+        return when(dt) {
+            in ByteDatatypes -> 1
+            in WordDatatypes -> 2
+            DataType.FLOAT -> machine.FLOAT_MEM_SIZE
+            in PassByReferenceDatatypes -> machine.POINTER_MEM_SIZE
+            else -> -9999999
+        }
+    }
+}
+

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

@@ -1,16 +1,13 @@
 package prog8.compiler.target.c64
 
-import prog8.ast.Program
-import prog8.compiler.*
-import prog8.compiler.target.CpuType
-import prog8.compiler.target.IMachineDefinition
-import prog8.compiler.target.IMachineFloat
-import prog8.parser.ModuleImporter
+import prog8.compiler.target.cbm.viceMonListPostfix
+import prog8.compilerinterface.*
 import java.io.IOException
+import java.nio.file.Path
 import kotlin.math.absoluteValue
 import kotlin.math.pow
 
-internal object C64MachineDefinition: IMachineDefinition {
+object C64MachineDefinition: IMachineDefinition {
 
     override val cpu = CpuType.CPU6502
 
@@ -30,16 +27,23 @@ internal object C64MachineDefinition: IMachineDefinition {
 
     override fun getFloat(num: Number) = Mflpt5.fromNumber(num)
 
-    override fun importLibs(compilerOptions: CompilationOptions, importer: ModuleImporter, program: Program) {
-        if (compilerOptions.launcher == LauncherType.BASIC || compilerOptions.output == OutputType.PRG)
-            importer.importLibraryModule(program, "syslib")
+    override fun importLibs(compilerOptions: CompilationOptions, compilationTargetName: String): List<String> {
+        return if (compilerOptions.launcher == LauncherType.BASIC || compilerOptions.output == OutputType.PRG)
+            listOf("syslib")
+        else
+            emptyList()
     }
 
-    override fun launchEmulator(programName: String) {
+    override fun launchEmulator(selectedEmulator: Int, programNameWithPath: Path) {
+        if(selectedEmulator!=1) {
+            System.err.println("The c64 target only supports the main emulator (Vice).")
+            return
+        }
+
         for(emulator in listOf("x64sc", "x64")) {
             println("\nStarting C-64 emulator $emulator...")
-            val cmdline = listOf(emulator, "-silent", "-moncommands", "$programName.vice-mon-list",
-                    "-autostartprgmode", "1", "-autostart-warp", "-autostart", programName + ".prg")
+            val cmdline = listOf(emulator, "-silent", "-moncommands", "${programNameWithPath}.$viceMonListPostfix",
+                    "-autostartprgmode", "1", "-autostart-warp", "-autostart", "${programNameWithPath}.prg")
             val processb = ProcessBuilder(cmdline).inheritIO()
             val process: Process
             try {
@@ -70,7 +74,7 @@ internal object C64MachineDefinition: IMachineDefinition {
             "sta", "stx", "sty", "tas", "tax", "tay", "tsx", "txa", "txs", "tya", "xaa")
 
 
-    internal class C64Zeropage(options: CompilationOptions) : Zeropage(options) {
+    class C64Zeropage(options: CompilationOptions) : Zeropage(options) {
 
         override val SCRATCH_B1 = 0x02      // temp storage for a single byte
         override val SCRATCH_REG = 0x03     // temp storage for a register, must be B1+1
@@ -79,13 +83,12 @@ internal object C64MachineDefinition: IMachineDefinition {
 
 
         init {
-            if (options.floats && options.zeropage !in setOf(ZeropageType.FLOATSAFE, ZeropageType.BASICSAFE, ZeropageType.DONTUSE ))
-                throw CompilerException("when floats are enabled, zero page type should be 'floatsafe' or 'basicsafe' or 'dontuse'")
+            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'")
 
             if (options.zeropage == ZeropageType.FULL) {
                 free.addAll(0x04..0xf9)
                 free.add(0xff)
-                free.removeAll(listOf(SCRATCH_B1, SCRATCH_REG, SCRATCH_W1, SCRATCH_W1 + 1, SCRATCH_W2, SCRATCH_W2 + 1))
                 free.removeAll(listOf(0xa0, 0xa1, 0xa2, 0x91, 0xc0, 0xc5, 0xcb, 0xf5, 0xf6))        // these are updated by IRQ
             } else {
                 if (options.zeropage == ZeropageType.KERNALSAFE || options.zeropage == ZeropageType.FLOATSAFE) {
@@ -102,13 +105,14 @@ internal object C64MachineDefinition: IMachineDefinition {
                             0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 0x7a, 0x7b, 0x7c,
                             0x7d, 0x7e, 0x7f, 0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89, 0x8a,
                             0x8b, 0x8c, 0x8d, 0x8e, 0x8f, 0xff
-                            // 0x90-0xfa is 'kernel work storage area'
+                            // 0x90-0xfa is 'kernal work storage area'
                     ))
                 }
 
                 if (options.zeropage == ZeropageType.FLOATSAFE) {
-                    // remove the zero page locations used for floating point operations from the free list
+                    // remove the zeropage locations used for floating point operations from the free list
                     free.removeAll(listOf(
+                            0x22, 0x23, 0x24, 0x25,
                             0x10, 0x11, 0x12, 0x26, 0x27, 0x28, 0x29, 0x2a,
                             0x57, 0x58, 0x59, 0x5a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f, 0x60,
                             0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68,
@@ -117,7 +121,7 @@ internal object C64MachineDefinition: IMachineDefinition {
                     ))
                 }
 
-                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(0x04, 0x05, 0x06, 0x0a, 0x0e,
@@ -128,17 +132,13 @@ internal object C64MachineDefinition: IMachineDefinition {
                     free.clear()
                 }
             }
-            require(SCRATCH_B1 !in free)
-            require(SCRATCH_REG !in free)
-            require(SCRATCH_W1 !in free)
-            require(SCRATCH_W2 !in free)
 
-            for (reserved in options.zpReserved)
-                reserve(reserved)
+            removeReservedFromFreePool()
         }
     }
 
-    internal data class Mflpt5(val b0: Short, val b1: Short, val b2: Short, val b3: Short, val b4: Short): IMachineFloat {
+    data class Mflpt5(val b0: Short, val b1: Short, val b2: Short, val b3: Short, val b4: Short):
+        IMachineFloat {
 
         companion object {
             val zero = Mflpt5(0, 0, 0, 0, 0)
@@ -149,7 +149,7 @@ internal object C64MachineDefinition: IMachineDefinition {
 
                 val flt = num.toDouble()
                 if (flt < FLOAT_MAX_NEGATIVE || flt > FLOAT_MAX_POSITIVE)
-                    throw CompilerException("floating point number out of 5-byte mflpt range: $this")
+                    throw InternalCompilerException("floating point number out of 5-byte mflpt range: $this")
                 if (flt == 0.0)
                     return zero
 
@@ -170,7 +170,7 @@ internal object C64MachineDefinition: IMachineDefinition {
 
                 return when {
                     exponent < 0 -> zero  // underflow, use zero instead
-                    exponent > 255 -> throw CompilerException("floating point overflow: $this")
+                    exponent > 255 -> throw InternalCompilerException("floating point overflow: $this")
                     exponent == 0 -> zero
                     else -> {
                         val mantLong = mantissa.toLong()

codeGeneration/src/prog8/compiler/target/cbm/AssemblyProgram.kt

@@ -1,34 +1,50 @@
-package prog8.compiler.target.c64
+package prog8.compiler.target.cbm
 
-import prog8.compiler.CompilationOptions
-import prog8.compiler.OutputType
-import prog8.compiler.target.CompilationTarget
-import prog8.compiler.target.IAssemblyProgram
-import prog8.compiler.target.generatedLabelPrefix
+import com.github.michaelbull.result.Ok
+import com.github.michaelbull.result.Result
+import com.github.michaelbull.result.mapError
+import prog8.compilerinterface.CompilationOptions
+import prog8.compilerinterface.IAssemblyProgram
+import prog8.compilerinterface.OutputType
+import prog8.compilerinterface.generatedLabelPrefix
+import prog8.parser.SourceCode
+import java.io.File
 import java.nio.file.Path
-import kotlin.system.exitProcess
+import kotlin.io.path.Path
+import kotlin.io.path.isRegularFile
+
+
+internal const val viceMonListPostfix = "vice-mon-list"
+
+class AssemblyProgram(
+        override val valid: Boolean,
+        override val name: String,
+        outputDir: Path,
+        private val compTarget: String) : IAssemblyProgram {
 
-class AssemblyProgram(override val name: String, outputDir: Path) : IAssemblyProgram {
     private val assemblyFile = outputDir.resolve("$name.asm")
     private val prgFile = outputDir.resolve("$name.prg")
     private val binFile = outputDir.resolve("$name.bin")
-    private val viceMonListFile = outputDir.resolve("$name.vice-mon-list")
+    private val viceMonListFile = outputDir.resolve("$name.$viceMonListPostfix")
 
-    override fun assemble(options: CompilationOptions) {
+    override fun assemble(quiet: Boolean, options: CompilationOptions): Int {
         // 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",
                 "--dump-labels", "--vice-labels", "-l", viceMonListFile.toString(), "--no-monitor")
 
+        if(quiet)
+            command.add("--quiet")
+
         val outFile = when (options.output) {
             OutputType.PRG -> {
                 command.add("--cbm-prg")
-                println("\nCreating prg for target ${CompilationTarget.instance.name}.")
+                println("\nCreating prg for target $compTarget.")
                 prgFile
             }
             OutputType.RAW -> {
                 command.add("--nostart")
-                println("\nCreating raw binary for target ${CompilationTarget.instance.name}.")
+                println("\nCreating raw binary for target $compTarget.")
                 binFile
             }
         }
@@ -36,13 +52,11 @@ class AssemblyProgram(override val name: String, outputDir: Path) : IAssemblyPro
 
         val proc = ProcessBuilder(command).inheritIO().start()
         val result = proc.waitFor()
-        if (result != 0) {
-            System.err.println("assembler failed with returncode $result")
-            exitProcess(result)
+        if (result == 0) {
+            removeGeneratedLabelsFromMonlist()
+            generateBreakpointList()
         }
-
-        removeGeneratedLabelsFromMonlist()
-        generateBreakpointList()
+        return result
     }
 
     private fun removeGeneratedLabelsFromMonlist() {
@@ -72,3 +86,18 @@ class AssemblyProgram(override val name: String, outputDir: Path) : IAssemblyPro
         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)}").readText()
+        }.mapError { NoSuchFileException(File(filename)) }
+    } else {
+        val sib = Path(source.origin).resolveSibling(filename)
+        if (sib.isRegularFile())
+            Ok(SourceCode.File(sib).readText())
+        else
+            Ok(SourceCode.File(Path(filename)).readText())
+    }
+}

codeGeneration/src/prog8/compiler/target/cpu6502/codegen/AsmOptimizer.kt

@@ -1,4 +1,4 @@
-package prog8.compiler.target.c64.codegen
+package prog8.compiler.target.cpu6502.codegen
 
 
 // note: see https://wiki.nesdev.com/w/index.php/6502_assembly_optimisations
@@ -74,7 +74,7 @@ private fun getLinesBy(lines: MutableList<String>, windowSize: Int) =
         lines.withIndex().filter { it.value.isNotBlank() && !it.value.trimStart().startsWith(';') }.windowed(windowSize, partialWindows = false)
 
 private fun optimizeCmpSequence(linesByFour: List<List<IndexedValue<String>>>): List<Modification> {
-    // the when statement (on bytes) generates a sequence of:
+    // when statement (on bytes) generates a sequence of:
     //	 lda  $ce01,x
     //	 cmp  #$20
     //	 beq  check_prog8_s72choice_32
@@ -180,7 +180,7 @@ private fun optimizeSameAssignments(linesByFourteen: List<List<IndexedValue<Stri
 
 private fun optimizeStoreLoadSame(linesByFour: List<List<IndexedValue<String>>>): List<Modification> {
     // sta X + lda X,  sty X + ldy X,   stx X + ldx X  -> the second instruction can OFTEN be eliminated
-    // TODO this is not true if X is not a regular RAM memory address (but instead mapped I/O or ROM)
+    // TODO this is not true if X is not a regular RAM memory address (but instead mapped I/O or ROM) but how does this code know?
     val mods = mutableListOf<Modification>()
     for (pair in linesByFour) {
         val first = pair[0].value.trimStart()

codeGeneration/src/prog8/compiler/target/cpu6502/codegen/ForLoopsAsmGen.kt

@@ -1,14 +1,15 @@
-package prog8.compiler.target.c64.codegen
+package prog8.compiler.target.cpu6502.codegen
 
 import prog8.ast.Program
-import prog8.ast.base.ArrayElementTypes
+import prog8.ast.base.ArrayToElementTypes
 import prog8.ast.base.DataType
 import prog8.ast.base.RegisterOrPair
 import prog8.ast.expressions.IdentifierReference
 import prog8.ast.expressions.RangeExpr
 import prog8.ast.statements.ForLoop
-import prog8.compiler.AssemblyError
-import prog8.compiler.toHex
+import prog8.ast.toHex
+import prog8.compiler.target.AssemblyError
+import prog8.compilerinterface.toConstantIntegerRange
 import kotlin.math.absoluteValue
 
 internal class ForLoopsAsmGen(private val program: Program, private val asmgen: AsmGen) {
@@ -21,13 +22,13 @@ internal class ForLoopsAsmGen(private val program: Program, private val asmgen:
             is RangeExpr -> {
                 val range = (stmt.iterable as RangeExpr).toConstantIntegerRange()
                 if(range==null) {
-                    translateForOverNonconstRange(stmt, iterableDt.typeOrElse(DataType.STRUCT), stmt.iterable as RangeExpr)
+                    translateForOverNonconstRange(stmt, iterableDt.getOr(DataType.UNDEFINED), stmt.iterable as RangeExpr)
                 } else {
-                    translateForOverConstRange(stmt, iterableDt.typeOrElse(DataType.STRUCT), range)
+                    translateForOverConstRange(stmt, iterableDt.getOr(DataType.UNDEFINED), range)
                 }
             }
             is IdentifierReference -> {
-                translateForOverIterableVar(stmt, iterableDt.typeOrElse(DataType.STRUCT), stmt.iterable as IdentifierReference)
+                translateForOverIterableVar(stmt, iterableDt.getOr(DataType.UNDEFINED), stmt.iterable as IdentifierReference)
             }
             else -> throw AssemblyError("can't iterate over ${stmt.iterable.javaClass} - should have been replaced by a variable")
         }
@@ -40,6 +41,13 @@ internal class ForLoopsAsmGen(private val program: Program, private val asmgen:
         val modifiedLabel2 = asmgen.makeLabel("for_modifiedb")
         asmgen.loopEndLabels.push(endLabel)
         val stepsize=range.step.constValue(program)!!.number.toInt()
+
+        if(stepsize < -1) {
+            val limit = range.to.constValue(program)?.number?.toDouble()
+            if(limit==0.0)
+                throw AssemblyError("for unsigned loop variable it's not possible to count down with step != -1 from a non-const value to exactly zero due to value wrapping")
+        }
+
         when(iterableDt) {
             DataType.ARRAY_B, DataType.ARRAY_UB -> {
                 if (stepsize==1 || stepsize==-1) {
@@ -49,17 +57,17 @@ internal class ForLoopsAsmGen(private val program: Program, private val asmgen:
                     val incdec = if(stepsize==1) "inc" else "dec"
                     // loop over byte range via loopvar
                     val varname = asmgen.asmVariableName(stmt.loopVar)
-                    asmgen.assignExpressionToVariable(range.from, varname, ArrayElementTypes.getValue(iterableDt), null)
-                    asmgen.assignExpressionToVariable(range.to, "$modifiedLabel+1", ArrayElementTypes.getValue(iterableDt), null)
+                    asmgen.assignExpressionToVariable(range.from, varname, ArrayToElementTypes.getValue(iterableDt), null)
+                    asmgen.assignExpressionToVariable(range.to, "$modifiedLabel+1", ArrayToElementTypes.getValue(iterableDt), null)
                     asmgen.out(loopLabel)
                     asmgen.translate(stmt.body)
                     asmgen.out("""
                         lda  $varname
 $modifiedLabel          cmp  #0         ; modified 
                         beq  $endLabel
-                        $incdec  $varname
-                        jmp  $loopLabel
-$endLabel""")
+                        $incdec  $varname""")
+                    asmgen.jmp(loopLabel)
+                    asmgen.out(endLabel)
 
                 } else {
 
@@ -67,8 +75,8 @@ $endLabel""")
 
                     // loop over byte range via loopvar
                     val varname = asmgen.asmVariableName(stmt.loopVar)
-                    asmgen.assignExpressionToVariable(range.from, varname, ArrayElementTypes.getValue(iterableDt), null)
-                    asmgen.assignExpressionToVariable(range.to, "$modifiedLabel+1", ArrayElementTypes.getValue(iterableDt), null)
+                    asmgen.assignExpressionToVariable(range.from, varname, ArrayToElementTypes.getValue(iterableDt), null)
+                    asmgen.assignExpressionToVariable(range.to, "$modifiedLabel+1", ArrayToElementTypes.getValue(iterableDt), null)
                     asmgen.out(loopLabel)
                     asmgen.translate(stmt.body)
                     if(stepsize>0) {
@@ -117,16 +125,15 @@ $modifiedLabel2 cmp  #0    ; modified
                             asmgen.out("""
 +               inc  $varname
                 bne  $loopLabel
-                inc  $varname+1
-                jmp  $loopLabel
-                            """)
+                inc  $varname+1""")
+                            asmgen.jmp(loopLabel)
                         } else {
                             asmgen.out("""
 +               lda  $varname
                 bne  +
                 dec  $varname+1
-+               dec  $varname
-                jmp  $loopLabel""")
++               dec  $varname""")
+                            asmgen.jmp(loopLabel)
                         }
                         asmgen.out(endLabel)
                     }
@@ -239,7 +246,7 @@ $endLabel""")
         val endLabel = asmgen.makeLabel("for_end")
         asmgen.loopEndLabels.push(endLabel)
         val iterableName = asmgen.asmVariableName(ident)
-        val decl = ident.targetVarDecl(program.namespace)!!
+        val decl = ident.targetVarDecl(program)!!
         when(iterableDt) {
             DataType.STR -> {
                 asmgen.out("""
@@ -282,7 +289,7 @@ $loopLabel          sty  $indexVar
                         bne  $loopLabel
                         beq  $endLabel""")
                 }
-                if(length>=16 && asmgen.zeropage.available() > 0) {
+                if(length>=16 && asmgen.zeropage.hasByteAvailable()) {
                     // allocate index var on ZP
                     val zpAddr = asmgen.zeropage.allocate(indexVar, DataType.UBYTE, stmt.position, asmgen.errors)
                     asmgen.out("""$indexVar = $zpAddr  ; auto zp UBYTE""")
@@ -321,7 +328,7 @@ $loopLabel          sty  $indexVar
                         bne  $loopLabel
                         beq  $endLabel""")
                 }
-                if(length>=16 && asmgen.zeropage.available() > 0) {
+                if(length>=16 && asmgen.zeropage.hasByteAvailable()) {
                     // allocate index var on ZP
                     val zpAddr = asmgen.zeropage.allocate(indexVar, DataType.UBYTE, stmt.position, asmgen.errors)
                     asmgen.out("""$indexVar = $zpAddr  ; auto zp UBYTE""")
@@ -369,7 +376,7 @@ $loopLabel""")
                         throw AssemblyError("step 0, 1 and -1 should have been handled specifically  $stmt")
                     }
                     2 -> {
-                        if(range.last==255) {
+                        if(range.last==255 || range.last==254) {
                             asmgen.out("""
                                 inc  $varname
                                 beq  $endLabel
@@ -377,34 +384,34 @@ $loopLabel""")
                                 bne  $loopLabel""")
                         } else {
                             asmgen.out("""
+                                inc  $varname
+                                inc  $varname
                                 lda  $varname
-                                cmp  #${range.last}
-                                beq  $endLabel
-                                inc  $varname
-                                inc  $varname
-                                jmp  $loopLabel""")
+                                cmp  #${range.last+2}
+                                bne  $loopLabel""")
                         }
                     }
                     -2 -> {
                         when (range.last) {
-                            0 -> asmgen.out("""
-                                lda  $varname
-                                beq  $endLabel
-                                dec  $varname
-                                dec  $varname
-                                jmp  $loopLabel""")
+                            0 -> {
+                                asmgen.out("""
+                                    lda  $varname
+                                    beq  $endLabel
+                                    dec  $varname
+                                    dec  $varname""")
+                                asmgen.jmp(loopLabel)
+                            }
                             1 -> asmgen.out("""
-                                dec  $varname
-                                beq  $endLabel
-                                dec  $varname
-                                bne  $loopLabel""")
+                                    dec  $varname
+                                    beq  $endLabel
+                                    dec  $varname
+                                    bne  $loopLabel""")
                             else -> asmgen.out("""
-                                lda  $varname
-                                cmp  #${range.last}
-                                beq  $endLabel
-                                dec  $varname
-                                dec  $varname
-                                jmp  $loopLabel""")
+                                    dec  $varname
+                                    dec  $varname
+                                    lda  $varname
+                                    cmp  #${range.last-2}
+                                    bne  $loopLabel""")
                         }
                     }
                     else -> {
@@ -415,8 +422,8 @@ $loopLabel""")
                             beq  $endLabel
                             clc
                             adc  #${range.step}
-                            sta  $varname
-                            jmp  $loopLabel""")
+                            sta  $varname""")
+                        asmgen.jmp(loopLabel)
                     }
                 }
                 asmgen.out(endLabel)
@@ -452,9 +459,9 @@ $loopLabel""")
                             sta  $varname
                             lda  $varname+1
                             adc  #>${range.step}
-                            sta  $varname+1
-                            jmp  $loopLabel
-$endLabel""")
+                            sta  $varname+1""")
+                        asmgen.jmp(loopLabel)
+                        asmgen.out(endLabel)
                     }
                 }
             }
@@ -480,11 +487,10 @@ $loopLabel""")
 $endLabel""")
         } else {
             asmgen.out("""
-                lda  $varname
-                cmp  #${range.last}
-                beq  $endLabel
                 inc  $varname
-                jmp  $loopLabel
+                lda  $varname
+                cmp  #${range.last+1}
+                bne  $loopLabel
 $endLabel""")
         }
         asmgen.loopEndLabels.pop()
@@ -505,23 +511,22 @@ $loopLabel""")
                 asmgen.out("""
                     lda  $varname
                     beq  $endLabel
-                    dec  $varname
-                    jmp  $loopLabel
-$endLabel""")
+                    dec  $varname""")
+                asmgen.jmp(loopLabel)
+                asmgen.out(endLabel)
             }
             1 -> {
                 asmgen.out("""
                     dec  $varname
-                    jmp  $loopLabel
+                    bne  $loopLabel
 $endLabel""")
             }
             else -> {
                 asmgen.out("""
-                    lda  $varname
-                    cmp  #${range.last}
-                    beq  $endLabel
                     dec  $varname
-                    jmp  $loopLabel
+                    lda  $varname
+                    cmp  #${range.last-1}
+                    bne  $loopLabel
 $endLabel""")
             }
         }
@@ -546,13 +551,12 @@ $loopLabel""")
             bne  +
             lda  $varname+1
             cmp  #>${range.last}
-            bne  +
             beq  $endLabel
 +           inc  $varname
             bne  $loopLabel
-            inc  $varname+1
-            jmp  $loopLabel
-$endLabel""")
+            inc  $varname+1""")
+        asmgen.jmp(loopLabel)
+        asmgen.out(endLabel)
         asmgen.loopEndLabels.pop()
     }
 
@@ -574,17 +578,16 @@ $loopLabel""")
             bne  +
             lda  $varname+1
             cmp  #>${range.last}
-            bne  +
             beq  $endLabel
 +           lda  $varname
             bne  +
             dec  $varname+1
-+           dec  $varname
-            jmp  $loopLabel
-$endLabel""")
++           dec  $varname""")
+        asmgen.jmp(loopLabel)
+        asmgen.out(endLabel)
         asmgen.loopEndLabels.pop()
     }
 
     private fun assignLoopvar(stmt: ForLoop, range: RangeExpr) =
-        asmgen.assignExpressionToVariable(range.from, asmgen.asmVariableName(stmt.loopVar), stmt.loopVarDt(program).typeOrElse(DataType.STRUCT), stmt.definingSubroutine())
+        asmgen.assignExpressionToVariable(range.from, asmgen.asmVariableName(stmt.loopVar), stmt.loopVarDt(program).getOr(DataType.UNDEFINED), stmt.definingSubroutine)
 }

codeGeneration/src/prog8/compiler/target/cpu6502/codegen/FunctionCallAsmGen.kt

@@ -1,15 +1,20 @@
-package prog8.compiler.target.c64.codegen
+package prog8.compiler.target.cpu6502.codegen
 
 import prog8.ast.IFunctionCall
 import prog8.ast.Node
 import prog8.ast.Program
 import prog8.ast.base.*
 import prog8.ast.expressions.*
-import prog8.ast.statements.*
-import prog8.compiler.AssemblyError
-import prog8.compiler.target.CompilationTarget
-import prog8.compiler.target.CpuType
-import prog8.compiler.target.c64.codegen.assignment.*
+import prog8.ast.statements.InlineAssembly
+import prog8.ast.statements.RegisterOrStatusflag
+import prog8.ast.statements.Subroutine
+import prog8.ast.statements.SubroutineParameter
+import prog8.compiler.target.AssemblyError
+import prog8.compiler.target.cpu6502.codegen.assignment.AsmAssignSource
+import prog8.compiler.target.cpu6502.codegen.assignment.AsmAssignTarget
+import prog8.compiler.target.cpu6502.codegen.assignment.AsmAssignment
+import prog8.compiler.target.cpu6502.codegen.assignment.TargetStorageKind
+import prog8.compilerinterface.CpuType
 
 
 internal class FunctionCallAsmGen(private val program: Program, private val asmgen: AsmGen) {
@@ -22,62 +27,79 @@ internal class FunctionCallAsmGen(private val program: Program, private val asmg
     }
 
     internal fun saveXbeforeCall(stmt: IFunctionCall) {
-        val sub = stmt.target.targetSubroutine(program.namespace) ?: throw AssemblyError("undefined subroutine ${stmt.target}")
+        val sub = stmt.target.targetSubroutine(program) ?: throw AssemblyError("undefined subroutine ${stmt.target}")
         if(sub.shouldSaveX()) {
             val regSaveOnStack = sub.asmAddress==null       // rom-routines don't require registers to be saved on stack, normal subroutines do because they can contain nested calls
-            val (keepAonEntry: Boolean, keepAonReturn: Boolean) = sub.shouldKeepA()
             if(regSaveOnStack)
-                asmgen.saveRegisterStack(CpuRegister.X, keepAonEntry)
+                asmgen.saveRegisterStack(CpuRegister.X, sub.shouldKeepA().saveOnEntry)
             else
-                asmgen.saveRegisterLocal(CpuRegister.X, (stmt as Node).definingSubroutine()!!)
+                asmgen.saveRegisterLocal(CpuRegister.X, (stmt as Node).definingSubroutine!!)
         }
     }
 
     internal fun restoreXafterCall(stmt: IFunctionCall) {
-        val sub = stmt.target.targetSubroutine(program.namespace) ?: throw AssemblyError("undefined subroutine ${stmt.target}")
+        val sub = stmt.target.targetSubroutine(program) ?: throw AssemblyError("undefined subroutine ${stmt.target}")
         if(sub.shouldSaveX()) {
             val regSaveOnStack = sub.asmAddress==null       // rom-routines don't require registers to be saved on stack, normal subroutines do because they can contain nested calls
-            val (keepAonEntry: Boolean, keepAonReturn: Boolean) = sub.shouldKeepA()
-
             if(regSaveOnStack)
-                asmgen.restoreRegisterStack(CpuRegister.X, keepAonReturn)
+                asmgen.restoreRegisterStack(CpuRegister.X, sub.shouldKeepA().saveOnReturn)
             else
                 asmgen.restoreRegisterLocal(CpuRegister.X)
         }
     }
 
     internal fun translateFunctionCall(stmt: IFunctionCall) {
-        // Output only the code to setup the parameters and perform the actual call
+        // Output only the code to set up the parameters and perform the actual call
         // NOTE: does NOT output the code to deal with the result values!
         // NOTE: does NOT output code to save/restore the X register for this call! Every caller should deal with this in their own way!!
         //       (you can use subroutine.shouldSaveX() and saveX()/restoreX() routines as a help for this)
 
-        val sub = stmt.target.targetSubroutine(program.namespace) ?: throw AssemblyError("undefined subroutine ${stmt.target}")
+        val sub = stmt.target.targetSubroutine(program) ?: throw AssemblyError("undefined subroutine ${stmt.target}")
         val subName = asmgen.asmSymbolName(stmt.target)
         if(stmt.args.isNotEmpty()) {
+
             if(sub.asmParameterRegisters.isEmpty()) {
                 // via variables
                 for(arg in sub.parameters.withIndex().zip(stmt.args)) {
                     argumentViaVariable(sub, arg.first, arg.second)
                 }
             } else {
-                // via registers
+                require(sub.isAsmSubroutine)
                 if(sub.parameters.size==1) {
                     // just a single parameter, no risk of clobbering registers
                     argumentViaRegister(sub, IndexedValue(0, sub.parameters.single()), stmt.args[0])
                 } else {
+
+                    fun isNoClobberRisk(expr: Expression): Boolean {
+                        if(expr is AddressOf ||
+                                expr is NumericLiteralValue ||
+                                expr is StringLiteralValue ||
+                                expr is ArrayLiteralValue ||
+                                expr is IdentifierReference)
+                            return true
+
+                        if(expr is FunctionCall) {
+                            if(expr.target.nameInSource==listOf("lsb") || expr.target.nameInSource==listOf("msb"))
+                                return isNoClobberRisk(expr.args[0])
+                            if(expr.target.nameInSource==listOf("mkword"))
+                                return isNoClobberRisk(expr.args[0]) && isNoClobberRisk(expr.args[1])
+                        }
+
+                        return false
+                    }
+
                     when {
-                        stmt.args.all {it is AddressOf ||
-                                it is NumericLiteralValue ||
-                                it is StringLiteralValue ||
-                                it is ArrayLiteralValue ||
-                                it is IdentifierReference} -> {
+                        stmt.args.all {isNoClobberRisk(it)} -> {
                             // There's no risk of clobbering for these simple argument types. Optimize the register loading directly from these values.
+                            // register assignment order: 1) cx16 virtual word registers, 2) actual CPU registers, 3) CPU Carry status flag.
                             val argsInfo = sub.parameters.withIndex().zip(stmt.args).zip(sub.asmParameterRegisters)
-                            val (vregsArgsInfo, otherRegsArgsInfo) = argsInfo.partition { it.second.registerOrPair in Cx16VirtualRegisters }
-                            for(arg in vregsArgsInfo)
+                            val (cx16virtualRegs, args2) = argsInfo.partition { it.second.registerOrPair in Cx16VirtualRegisters }
+                            val (cpuRegs, statusRegs) = args2.partition { it.second.registerOrPair!=null }
+                            for(arg in cx16virtualRegs)
                                 argumentViaRegister(sub, arg.first.first, arg.first.second)
-                            for(arg in otherRegsArgsInfo)
+                            for(arg in cpuRegs)
+                                argumentViaRegister(sub, arg.first.first, arg.first.second)
+                            for(arg in statusRegs)
                                 argumentViaRegister(sub, arg.first.first, arg.first.second)
                         }
                         else -> {
@@ -89,17 +111,22 @@ internal class FunctionCallAsmGen(private val program: Program, private val asmg
             }
         }
 
-        if(sub.inline && asmgen.options.optimize) {
-            if(sub.containsDefinedVariables())
-                throw AssemblyError("can't inline sub with vars")
-            if(!sub.isAsmSubroutine && sub.parameters.isNotEmpty())
-                throw AssemblyError("can't inline a non-asm subroutine with parameters")
-            asmgen.out("  \t; inlined routine follows: ${sub.name} from ${sub.position}")
-            val statements = sub.statements.filter { it !is ParameterVarDecl && it !is Directive }
-            statements.forEach { asmgen.translate(it) }
-        }
-        else {
+        if(!sub.inline || !asmgen.options.optimize) {
             asmgen.out("  jsr  $subName")
+        } else {
+            // inline the subroutine.
+            // 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)
+
+            // note: for now, this is only reliably supported for asmsubs.
+            if(!sub.isAsmSubroutine)
+                throw AssemblyError("can only reliably inline asmsub routines at this time")
+
+            asmgen.out("  \t; inlined routine follows: ${sub.name}")
+            val assembly = sub.statements.single() as InlineAssembly
+            asmgen.translate(assembly)
+            asmgen.out("  \t; inlined routine end: ${sub.name}")
         }
 
         // remember: dealing with the X register and/or dealing with return values is the responsibility of the caller
@@ -108,14 +135,25 @@ internal class FunctionCallAsmGen(private val program: Program, private val asmg
     private fun registerArgsViaStackEvaluation(stmt: IFunctionCall, sub: Subroutine) {
         // 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.
+        // TODO find another way to prepare the arguments, without using the eval stack
 
         if(sub.parameters.isEmpty())
             return
 
+
         // 1. load all arguments reversed onto the stack: first arg goes last (is on top).
+
         for (arg in stmt.args.reversed())
             asmgen.translateExpression(arg)
 
+        // TODO here's an alternative to the above, but for now generates bigger code due to intermediate register steps:
+//        for (arg in stmt.args.reversed()) {
+//            // note this stuff below is needed to (eventually) avoid calling asmgen.translateExpression()
+//            // TODO also This STILL requires the translateNormalAssignment() to be fixed to avoid stack eval for expressions...
+//            val dt = arg.inferType(program).getOr(DataType.UNDEFINED)
+//            asmgen.assignExpressionTo(arg, AsmAssignTarget(TargetStorageKind.STACK, program, asmgen, dt, sub))
+//        }
+
         var argForCarry: IndexedValue<Pair<Expression, RegisterOrStatusflag>>? = null
         var argForXregister: IndexedValue<Pair<Expression, RegisterOrStatusflag>>? = null
         var argForAregister: IndexedValue<Pair<Expression, RegisterOrStatusflag>>? = null
@@ -130,11 +168,11 @@ internal class FunctionCallAsmGen(private val program: Program, private val asmg
                     argForCarry = argi
                 }
                 argi.value.second.statusflag != null -> throw AssemblyError("can only use Carry as status flag parameter")
-                argi.value.second.registerOrPair in setOf(RegisterOrPair.X, RegisterOrPair.AX, RegisterOrPair.XY) -> {
+                argi.value.second.registerOrPair in arrayOf(RegisterOrPair.X, RegisterOrPair.AX, RegisterOrPair.XY) -> {
                     require(argForXregister==null)
                     argForXregister = argi
                 }
-                argi.value.second.registerOrPair in setOf(RegisterOrPair.A, RegisterOrPair.AY) -> {
+                argi.value.second.registerOrPair in arrayOf(RegisterOrPair.A, RegisterOrPair.AY) -> {
                     require(argForAregister == null)
                     argForAregister = argi
                 }
@@ -146,21 +184,31 @@ internal class FunctionCallAsmGen(private val program: Program, private val asmg
                     when (sub.parameters[argi.index].type) {
                         in ByteDatatypes -> {
                             // only load the lsb of the virtual register
-                            asmgen.out("""
+                            asmgen.out(
+                                """
                                 lda  P8ESTACK_LO$plusIdxStr,x
-                                sta  cx16.${argi.value.second.registerOrPair.toString().toLowerCase()}
+                                sta  cx16.${argi.value.second.registerOrPair.toString().lowercase()}
                             """)
-                            if (CompilationTarget.instance.machine.cpu == CpuType.CPU65c02)
-                                asmgen.out("  stz  cx16.${argi.value.second.registerOrPair.toString().toLowerCase()}+1")
+                            if (asmgen.isTargetCpu(CpuType.CPU65c02))
+                                asmgen.out(
+                                    "  stz  cx16.${
+                                        argi.value.second.registerOrPair.toString().lowercase()
+                                    }+1")
                             else
-                                asmgen.out("  lda  #0 |  sta  cx16.${argi.value.second.registerOrPair.toString().toLowerCase()}+1")
+                                asmgen.out(
+                                    "  lda  #0 |  sta  cx16.${
+                                        argi.value.second.registerOrPair.toString().lowercase()
+                                    }+1")
                         }
-                        in WordDatatypes ->
-                            asmgen.out("""
+                        in WordDatatypes, in IterableDatatypes ->
+                            asmgen.out(
+                                """
                                 lda  P8ESTACK_LO$plusIdxStr,x
-                                sta  cx16.${argi.value.second.registerOrPair.toString().toLowerCase()}
+                                sta  cx16.${argi.value.second.registerOrPair.toString().lowercase()}
                                 lda  P8ESTACK_HI$plusIdxStr,x
-                                sta  cx16.${argi.value.second.registerOrPair.toString().toLowerCase()}+1
+                                sta  cx16.${
+                                    argi.value.second.registerOrPair.toString().lowercase()
+                                }+1
                             """)
                         else -> throw AssemblyError("weird dt")
                     }
@@ -215,7 +263,7 @@ internal class FunctionCallAsmGen(private val program: Program, private val asmg
         val valueIDt = value.inferType(program)
         if(!valueIDt.isKnown)
             throw AssemblyError("unknown dt")
-        val valueDt = valueIDt.typeOrElse(DataType.STRUCT)
+        val valueDt = valueIDt.getOr(DataType.UNDEFINED)
         if(!isArgumentTypeCompatible(valueDt, parameter.value.type))
             throw AssemblyError("argument type incompatible")
 
@@ -228,7 +276,7 @@ internal class FunctionCallAsmGen(private val program: Program, private val asmg
         val valueIDt = value.inferType(program)
         if(!valueIDt.isKnown)
             throw AssemblyError("unknown dt")
-        val valueDt = valueIDt.typeOrElse(DataType.STRUCT)
+        val valueDt = valueIDt.getOr(DataType.UNDEFINED)
         if(!isArgumentTypeCompatible(valueDt, parameter.value.type))
             throw AssemblyError("argument type incompatible")
 
@@ -240,71 +288,66 @@ internal class FunctionCallAsmGen(private val program: Program, private val asmg
             if(valueDt largerThan requiredDt)
                 throw AssemblyError("can only convert byte values to word param types")
         }
-        when {
-            statusflag!=null -> {
-                if(requiredDt!=valueDt)
-                    throw AssemblyError("for statusflag, byte value is required")
-                if (statusflag == Statusflag.Pc) {
-                    // this param needs to be set last, right before the jsr
-                    // for now, this is already enforced on the subroutine definition by the Ast Checker
-                    when(value) {
-                        is NumericLiteralValue -> {
-                            val carrySet = value.number.toInt() != 0
-                            asmgen.out(if(carrySet) "  sec" else "  clc")
-                        }
-                        is IdentifierReference -> {
-                            val sourceName = asmgen.asmVariableName(value)
-                            asmgen.out("""
-            pha
-            lda  $sourceName
-            beq  +
-            sec  
-            bcs  ++
-+           clc
-+           pla
-""")
-                        }
-                        else -> {
-                            asmgen.assignExpressionToRegister(value, RegisterOrPair.A)
-                            asmgen.out("""
-                                beq  +
-                                sec
-                                bcs  ++
-+                               clc
-+""")
-                        }
+        if (statusflag!=null) {
+            if(requiredDt!=valueDt)
+                throw AssemblyError("for statusflag, byte value is required")
+            if (statusflag == Statusflag.Pc) {
+                // this param needs to be set last, right before the jsr
+                // for now, this is already enforced on the subroutine definition by the Ast Checker
+                when(value) {
+                    is NumericLiteralValue -> {
+                        val carrySet = value.number.toInt() != 0
+                        asmgen.out(if(carrySet) "  sec" else "  clc")
+                    }
+                    is IdentifierReference -> {
+                        val sourceName = asmgen.asmVariableName(value)
+                        asmgen.out("""
+                pha
+                lda  $sourceName
+                beq  +
+                sec  
+                bcs  ++
+    +           clc
+    +           pla
+    """)
+                    }
+                    else -> {
+                        asmgen.assignExpressionToRegister(value, RegisterOrPair.A)
+                        asmgen.out("""
+                                    beq  +
+                                    sec
+                                    bcs  ++
+    +                               clc
+    +""")
                     }
                 }
-                else throw AssemblyError("can only use Carry as status flag parameter")
-            }
-            else -> {
-                // via register or register pair
-                register!!
-                if(requiredDt largerThan valueDt) {
-                    // we need to sign extend the source, do this via temporary word variable
-                    val scratchVar = asmgen.asmVariableName("P8ZP_SCRATCH_W1")
-                    asmgen.assignExpressionToVariable(value, scratchVar, DataType.UBYTE, sub)
-                    asmgen.signExtendVariableLsb(scratchVar, valueDt)
-                    asmgen.assignVariableToRegister(scratchVar, register)
-                }
-                else {
-                    val target: AsmAssignTarget =
-                        if(parameter.value.type in ByteDatatypes && (register==RegisterOrPair.AX || register == RegisterOrPair.AY || register==RegisterOrPair.XY || register in Cx16VirtualRegisters))
-                            AsmAssignTarget(TargetStorageKind.REGISTER, program, asmgen, parameter.value.type, sub, register = register)
-                        else
-                            AsmAssignTarget.fromRegisters(register, sub, program, asmgen)
-                    val src = if(valueDt in PassByReferenceDatatypes) {
-                        if(value is IdentifierReference) {
-                            val addr = AddressOf(value, Position.DUMMY)
-                            AsmAssignSource.fromAstSource(addr, program, asmgen).adjustSignedUnsigned(target)
-                        } else {
-                            AsmAssignSource.fromAstSource(value, program, asmgen).adjustSignedUnsigned(target)
-                        }
+            } else throw AssemblyError("can only use Carry as status flag parameter")
+        }
+        else {
+            // via register or register pair
+            register!!
+            if(requiredDt largerThan valueDt) {
+                // we need to sign extend the source, do this via temporary word variable
+                asmgen.assignExpressionToVariable(value, "P8ZP_SCRATCH_W1", DataType.UBYTE, sub)
+                asmgen.signExtendVariableLsb("P8ZP_SCRATCH_W1", valueDt)
+                asmgen.assignVariableToRegister("P8ZP_SCRATCH_W1", register)
+            } else {
+                val target: AsmAssignTarget =
+                    if(parameter.value.type in ByteDatatypes && (register==RegisterOrPair.AX || register == RegisterOrPair.AY || register==RegisterOrPair.XY || register in Cx16VirtualRegisters))
+                        AsmAssignTarget(TargetStorageKind.REGISTER, program, asmgen, parameter.value.type, sub, register = register)
+                    else
+                        AsmAssignTarget.fromRegisters(register, false, sub, program, asmgen)
+                val src = if(valueDt in PassByReferenceDatatypes) {
+                    if(value is IdentifierReference) {
+                        val addr = AddressOf(value, Position.DUMMY)
+                        AsmAssignSource.fromAstSource(addr, program, asmgen).adjustSignedUnsigned(target)
                     } else {
                         AsmAssignSource.fromAstSource(value, program, asmgen).adjustSignedUnsigned(target)
                     }
-                    asmgen.translateNormalAssignment(AsmAssignment(src, target, false, Position.DUMMY))
+                } else {
+                    AsmAssignSource.fromAstSource(value, program, asmgen).adjustSignedUnsigned(target)
                 }
+                asmgen.translateNormalAssignment(AsmAssignment(src, target, false, program.memsizer, Position.DUMMY))
             }
         }
     }

codeGeneration/src/prog8/compiler/target/cpu6502/codegen/PostIncrDecrAsmGen.kt

@@ -1,12 +1,12 @@
-package prog8.compiler.target.c64.codegen
+package prog8.compiler.target.cpu6502.codegen
 
 import prog8.ast.Program
 import prog8.ast.base.*
 import prog8.ast.expressions.IdentifierReference
 import prog8.ast.expressions.NumericLiteralValue
 import prog8.ast.statements.PostIncrDecr
-import prog8.compiler.AssemblyError
-import prog8.compiler.toHex
+import prog8.ast.toHex
+import prog8.compiler.target.AssemblyError
 
 
 internal class PostIncrDecrAsmGen(private val program: Program, private val asmgen: AsmGen) {
@@ -15,11 +15,11 @@ internal class PostIncrDecrAsmGen(private val program: Program, private val asmg
         val targetIdent = stmt.target.identifier
         val targetMemory = stmt.target.memoryAddress
         val targetArrayIdx = stmt.target.arrayindexed
-        val scope = stmt.definingSubroutine()
+        val scope = stmt.definingSubroutine
         when {
             targetIdent!=null -> {
                 val what = asmgen.asmVariableName(targetIdent)
-                when (stmt.target.inferType(program).typeOrElse(DataType.STRUCT)) {
+                when (stmt.target.inferType(program).getOr(DataType.UNDEFINED)) {
                     in ByteDatatypes -> asmgen.out(if (incr) "  inc  $what" else "  dec  $what")
                     in WordDatatypes -> {
                         if(incr)
@@ -65,9 +65,10 @@ internal class PostIncrDecrAsmGen(private val program: Program, private val asmg
             }
             targetArrayIdx!=null -> {
                 val asmArrayvarname = asmgen.asmVariableName(targetArrayIdx.arrayvar)
-                val elementDt = targetArrayIdx.inferType(program).typeOrElse(DataType.STRUCT)
-                if(targetArrayIdx.indexer.indexNum!=null) {
-                    val indexValue = targetArrayIdx.indexer.constIndex()!! * elementDt.memorySize()
+                val elementDt = targetArrayIdx.inferType(program).getOr(DataType.UNDEFINED)
+                val constIndex = targetArrayIdx.indexer.constIndex()
+                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 WordDatatypes -> {

codeGeneration/src/prog8/compiler/target/cpu6502/codegen/assignment/AsmAssignment.kt

@@ -1,11 +1,12 @@
-package prog8.compiler.target.c64.codegen.assignment
+package prog8.compiler.target.cpu6502.codegen.assignment
 
 import prog8.ast.Program
 import prog8.ast.base.*
 import prog8.ast.expressions.*
 import prog8.ast.statements.*
-import prog8.compiler.AssemblyError
-import prog8.compiler.target.c64.codegen.AsmGen
+import prog8.compilerinterface.IMemSizer
+import prog8.compiler.target.AssemblyError
+import prog8.compiler.target.cpu6502.codegen.AsmGen
 
 
 internal enum class TargetStorageKind {
@@ -40,11 +41,12 @@ internal class AsmAssignTarget(val kind: TargetStorageKind,
 {
     val constMemoryAddress by lazy { memory?.addressExpression?.constValue(program)?.number?.toInt() ?: 0}
     val constArrayIndexValue by lazy { array?.indexer?.constIndex() }
-    val asmVarname: String
-        get() = if(array==null)
+    val asmVarname: String by lazy {
+        if (array == null)
             variableAsmName!!
         else
             asmgen.asmVariableName(array.arrayvar)
+    }
 
     lateinit var origAssign: AsmAssignment
 
@@ -58,23 +60,23 @@ internal class AsmAssignTarget(val kind: TargetStorageKind,
             val idt = inferType(program)
             if(!idt.isKnown)
                 throw AssemblyError("unknown dt")
-            val dt = idt.typeOrElse(DataType.STRUCT)
+            val dt = idt.getOr(DataType.UNDEFINED)
             when {
-                identifier != null -> AsmAssignTarget(TargetStorageKind.VARIABLE, program, asmgen, dt, assign.definingSubroutine(), variableAsmName = asmgen.asmVariableName(identifier!!), origAstTarget =  this)
-                arrayindexed != null -> AsmAssignTarget(TargetStorageKind.ARRAY, program, asmgen, dt, assign.definingSubroutine(), array = arrayindexed, origAstTarget =  this)
-                memoryAddress != null -> AsmAssignTarget(TargetStorageKind.MEMORY, program, asmgen, dt, assign.definingSubroutine(), memory =  memoryAddress, origAstTarget =  this)
+                identifier != null -> AsmAssignTarget(TargetStorageKind.VARIABLE, program, asmgen, dt, assign.definingSubroutine, variableAsmName = asmgen.asmVariableName(identifier!!), origAstTarget =  this)
+                arrayindexed != null -> AsmAssignTarget(TargetStorageKind.ARRAY, program, asmgen, dt, assign.definingSubroutine, array = arrayindexed, origAstTarget =  this)
+                memoryAddress != null -> AsmAssignTarget(TargetStorageKind.MEMORY, program, asmgen, dt, assign.definingSubroutine, memory =  memoryAddress, origAstTarget =  this)
                 else -> throw AssemblyError("weird target")
             }
         }
 
-        fun fromRegisters(registers: RegisterOrPair, scope: Subroutine?, program: Program, asmgen: AsmGen): AsmAssignTarget =
+        fun fromRegisters(registers: RegisterOrPair, signed: Boolean, scope: Subroutine?, program: Program, asmgen: AsmGen): AsmAssignTarget =
                 when(registers) {
                     RegisterOrPair.A,
                     RegisterOrPair.X,
-                    RegisterOrPair.Y -> AsmAssignTarget(TargetStorageKind.REGISTER, program, asmgen, DataType.UBYTE, scope, register = registers)
+                    RegisterOrPair.Y -> AsmAssignTarget(TargetStorageKind.REGISTER, program, asmgen, if(signed) DataType.BYTE else DataType.UBYTE, scope, register = registers)
                     RegisterOrPair.AX,
                     RegisterOrPair.AY,
-                    RegisterOrPair.XY -> AsmAssignTarget(TargetStorageKind.REGISTER, program, asmgen, DataType.UWORD, scope, register = registers)
+                    RegisterOrPair.XY -> AsmAssignTarget(TargetStorageKind.REGISTER, program, asmgen, if(signed) DataType.WORD else DataType.UWORD, scope, register = registers)
                     RegisterOrPair.FAC1,
                     RegisterOrPair.FAC2 -> AsmAssignTarget(TargetStorageKind.REGISTER, program, asmgen, DataType.FLOAT, scope, register = registers)
                     RegisterOrPair.R0,
@@ -92,7 +94,7 @@ internal class AsmAssignTarget(val kind: TargetStorageKind,
                     RegisterOrPair.R12,
                     RegisterOrPair.R13,
                     RegisterOrPair.R14,
-                    RegisterOrPair.R15 -> AsmAssignTarget(TargetStorageKind.REGISTER, program, asmgen, DataType.UWORD, scope, register = registers)
+                    RegisterOrPair.R15 -> AsmAssignTarget(TargetStorageKind.REGISTER, program, asmgen, if(signed) DataType.WORD else DataType.UWORD, scope, register = registers)
                 }
     }
 }
@@ -104,7 +106,7 @@ internal class AsmAssignSource(val kind: SourceStorageKind,
                                private val variableAsmName: String? = null,
                                val array: ArrayIndexedExpression? = null,
                                val memory: DirectMemoryRead? = null,
-                               val register: CpuRegister? = null,
+                               val register: RegisterOrPair? = null,
                                val number: NumericLiteralValue? = null,
                                val expression: Expression? = null
 )
@@ -119,13 +121,7 @@ internal class AsmAssignSource(val kind: SourceStorageKind,
             asmgen.asmVariableName(array.arrayvar)
 
     companion object {
-        fun fromAstSource(indexer: ArrayIndex, program: Program, asmgen: AsmGen): AsmAssignSource {
-            return when {
-                indexer.indexNum!=null -> fromAstSource(indexer.indexNum!!, program, asmgen)
-                indexer.indexVar!=null -> fromAstSource(indexer.indexVar!!, program, asmgen)
-                else -> throw AssemblyError("weird indexer")
-            }
-        }
+        fun fromAstSource(indexer: ArrayIndex, program: Program, asmgen: AsmGen): AsmAssignSource = fromAstSource(indexer.indexExpr, program, asmgen)
 
         fun fromAstSource(value: Expression, program: Program, asmgen: AsmGen): AsmAssignSource {
             val cv = value.constValue(program)
@@ -137,18 +133,26 @@ internal class AsmAssignSource(val kind: SourceStorageKind,
                 is StringLiteralValue -> throw AssemblyError("string literal value should not occur anymore for asm generation")
                 is ArrayLiteralValue -> throw AssemblyError("array literal value should not occur anymore for asm generation")
                 is IdentifierReference -> {
-                    val dt = value.inferType(program).typeOrElse(DataType.STRUCT)
-                    AsmAssignSource(SourceStorageKind.VARIABLE, program, asmgen, dt, variableAsmName = asmgen.asmVariableName(value))
+                    val dt = value.inferType(program).getOr(DataType.UNDEFINED)
+                    val varName=asmgen.asmVariableName(value)
+                    // special case: "cx16.r[0-15]" are 16-bits virtual registers of the commander X16 system
+                    if(dt == DataType.UWORD && varName.lowercase().startsWith("cx16.r")) {
+                        val regStr = varName.lowercase().substring(5)
+                        val reg = RegisterOrPair.valueOf(regStr.uppercase())
+                        AsmAssignSource(SourceStorageKind.REGISTER, program, asmgen, dt, register = reg)
+                    } else {
+                        AsmAssignSource(SourceStorageKind.VARIABLE, program, asmgen, dt, variableAsmName = varName)
+                    }
                 }
                 is DirectMemoryRead -> {
                     AsmAssignSource(SourceStorageKind.MEMORY, program, asmgen, DataType.UBYTE, memory = value)
                 }
                 is ArrayIndexedExpression -> {
-                    val dt = value.inferType(program).typeOrElse(DataType.STRUCT)
+                    val dt = value.inferType(program).getOr(DataType.UNDEFINED)
                     AsmAssignSource(SourceStorageKind.ARRAY, program, asmgen, dt, array = value)
                 }
                 is FunctionCall -> {
-                    when (val sub = value.target.targetStatement(program.namespace)) {
+                    when (val sub = value.target.targetStatement(program)) {
                         is Subroutine -> {
                             val returnType = sub.returntypes.zip(sub.asmReturnvaluesRegisters).firstOrNull { rr -> rr.second.registerOrPair != null || rr.second.statusflag!=null }?.first
                                     ?: throw AssemblyError("can't translate zero return values in assignment")
@@ -159,7 +163,7 @@ internal class AsmAssignSource(val kind: SourceStorageKind,
                             val returnType = value.inferType(program)
                             if(!returnType.isKnown)
                                 throw AssemblyError("unknown dt")
-                            AsmAssignSource(SourceStorageKind.EXPRESSION, program, asmgen, returnType.typeOrElse(DataType.STRUCT), expression = value)
+                            AsmAssignSource(SourceStorageKind.EXPRESSION, program, asmgen, returnType.getOr(DataType.UNDEFINED), expression = value)
                         }
                         else -> {
                             throw AssemblyError("weird call")
@@ -170,7 +174,7 @@ internal class AsmAssignSource(val kind: SourceStorageKind,
                     val dt = value.inferType(program)
                     if(!dt.isKnown)
                         throw AssemblyError("unknown dt")
-                    AsmAssignSource(SourceStorageKind.EXPRESSION, program, asmgen, dt.typeOrElse(DataType.STRUCT), expression = value)
+                    AsmAssignSource(SourceStorageKind.EXPRESSION, program, asmgen, dt.getOr(DataType.UNDEFINED), expression = value)
                 }
             }
         }
@@ -198,12 +202,13 @@ internal class AsmAssignSource(val kind: SourceStorageKind,
 internal class AsmAssignment(val source: AsmAssignSource,
                              val target: AsmAssignTarget,
                              val isAugmentable: Boolean,
+                             memsizer: IMemSizer,
                              val position: Position) {
 
     init {
-        if(target.register !in setOf(RegisterOrPair.XY, RegisterOrPair.AX, RegisterOrPair.AY))
-            require(source.datatype != DataType.STRUCT) { "must not be placeholder datatype" }
-            require(source.datatype.memorySize() <= target.datatype.memorySize()) {
+        if(target.register !in arrayOf(RegisterOrPair.XY, RegisterOrPair.AX, RegisterOrPair.AY))
+            require(source.datatype != DataType.UNDEFINED) { "must not be placeholder/undefined datatype" }
+            require(memsizer.memorySize(source.datatype) <= memsizer.memorySize(target.datatype)) {
                 "source storage size must be less or equal to target datatype storage size"
             }
     }

codeGeneration/src/prog8/compiler/target/cx16/CX16MachineDefinition.kt

@@ -1,14 +1,13 @@
 package prog8.compiler.target.cx16
 
-import prog8.ast.Program
-import prog8.compiler.*
-import prog8.compiler.target.CpuType
-import prog8.compiler.target.IMachineDefinition
 import prog8.compiler.target.c64.C64MachineDefinition
-import prog8.parser.ModuleImporter
+import prog8.compiler.target.cbm.viceMonListPostfix
+import prog8.compilerinterface.*
 import java.io.IOException
+import java.nio.file.Path
 
-internal object CX16MachineDefinition: IMachineDefinition {
+
+object CX16MachineDefinition: IMachineDefinition {
 
     override val cpu = CpuType.CPU65c02
 
@@ -27,16 +26,35 @@ internal object CX16MachineDefinition: IMachineDefinition {
     override lateinit var zeropage: Zeropage
 
     override fun getFloat(num: Number) = C64MachineDefinition.Mflpt5.fromNumber(num)
-
-    override fun importLibs(compilerOptions: CompilationOptions, importer: ModuleImporter, program: Program) {
-        if (compilerOptions.launcher == LauncherType.BASIC || compilerOptions.output == OutputType.PRG)
-            importer.importLibraryModule(program, "syslib")
+    override fun importLibs(compilerOptions: CompilationOptions, compilationTargetName: String): List<String> {
+        return if (compilerOptions.launcher == LauncherType.BASIC || compilerOptions.output == OutputType.PRG)
+            listOf("syslib")
+        else
+            emptyList()
     }
 
-    override fun launchEmulator(programName: String) {
-        for(emulator in listOf("x16emu")) {
+    override fun launchEmulator(selectedEmulator: Int, programNameWithPath: Path) {
+        val emulatorName: String
+        val extraArgs: List<String>
+
+        when(selectedEmulator) {
+            1 -> {
+                emulatorName = "x16emu"
+                extraArgs = emptyList()
+            }
+            2 -> {
+                emulatorName = "box16"
+                extraArgs = listOf("-sym", "${programNameWithPath}.$viceMonListPostfix")
+            }
+            else -> {
+                System.err.println("Cx16 target only supports x16emu and box16 emulators.")
+                return
+            }
+        }
+
+        for(emulator in listOf(emulatorName)) {
             println("\nStarting Commander X16 emulator $emulator...")
-            val cmdline = listOf(emulator, "-scale", "2", "-run", "-prg", "$programName.prg")
+            val cmdline = listOf(emulator, "-scale", "2", "-run", "-prg", "${programNameWithPath}.prg") + extraArgs
             val processb = ProcessBuilder(cmdline).inheritIO()
             val process: Process
             try {
@@ -69,7 +87,7 @@ internal object CX16MachineDefinition: IMachineDefinition {
             "rmb", "smb", "stp", "wai")
 
 
-    internal class CX16Zeropage(options: CompilationOptions) : Zeropage(options) {
+    class CX16Zeropage(options: CompilationOptions) : Zeropage(options) {
 
         override val SCRATCH_B1 = 0x7a      // temp storage for a single byte
         override val SCRATCH_REG = 0x7b     // temp storage for a register, must be B1+1
@@ -78,38 +96,29 @@ internal object CX16MachineDefinition: IMachineDefinition {
 
 
         init {
-            if (options.floats && options.zeropage !in setOf(ZeropageType.BASICSAFE, ZeropageType.DONTUSE ))
-                throw CompilerException("when floats are enabled, zero page type should be 'basicsafe' or 'dontuse'")
+            if (options.floats && options.zeropage !in arrayOf(ZeropageType.BASICSAFE, ZeropageType.DONTUSE ))
+                throw InternalCompilerException("when floats are enabled, zero page type should be 'basicsafe' or 'dontuse'")
 
             // the addresses 0x02 to 0x21 (inclusive) are taken for sixteen virtual 16-bit api registers.
 
             when (options.zeropage) {
                 ZeropageType.FULL -> {
                     free.addAll(0x22..0xff)
-                    free.removeAll(listOf(SCRATCH_B1, SCRATCH_REG, SCRATCH_W1, SCRATCH_W1 + 1, SCRATCH_W2, SCRATCH_W2 + 1))
                 }
                 ZeropageType.KERNALSAFE -> {
                     free.addAll(0x22..0x7f)
                     free.addAll(0xa9..0xff)
-                    free.removeAll(listOf(SCRATCH_B1, SCRATCH_REG, SCRATCH_W1, SCRATCH_W1 + 1, SCRATCH_W2, SCRATCH_W2 + 1))
                 }
                 ZeropageType.BASICSAFE -> {
                     free.addAll(0x22..0x7f)
-                    free.removeAll(listOf(SCRATCH_B1, SCRATCH_REG, SCRATCH_W1, SCRATCH_W1 + 1, SCRATCH_W2, SCRATCH_W2 + 1))
                 }
                 ZeropageType.DONTUSE -> {
                     free.clear() // don't use zeropage at all
                 }
-                else -> throw CompilerException("for this machine target, zero page type 'floatsafe' is not available. ${options.zeropage}")
+                else -> throw InternalCompilerException("for this machine target, zero page type 'floatsafe' is not available. ${options.zeropage}")
             }
 
-            require(SCRATCH_B1 !in free)
-            require(SCRATCH_REG !in free)
-            require(SCRATCH_W1 !in free)
-            require(SCRATCH_W2 !in free)
-
-            for (reserved in options.zpReserved)
-                reserve(reserved)
+            removeReservedFromFreePool()
         }
     }
 }

codeGeneration/test/AsmGenTests.kt

@@ -0,0 +1,151 @@
+package prog8tests.asmgen
+
+import org.hamcrest.MatcherAssert.assertThat
+import org.hamcrest.Matchers.equalTo
+import org.junit.jupiter.api.Test
+import org.junit.jupiter.api.TestInstance
+import prog8.ast.Module
+import prog8.ast.Program
+import prog8.ast.base.DataType
+import prog8.ast.base.Position
+import prog8.ast.base.RegisterOrPair
+import prog8.ast.base.VarDeclType
+import prog8.ast.expressions.AddressOf
+import prog8.ast.expressions.IdentifierReference
+import prog8.ast.expressions.NumericLiteralValue
+import prog8.ast.statements.*
+import prog8.compiler.target.C64Target
+import prog8.compiler.target.c64.C64MachineDefinition
+import prog8.compiler.target.cpu6502.codegen.AsmGen
+import prog8.compilerinterface.*
+import prog8.parser.SourceCode
+import prog8tests.asmgen.helpers.DummyFunctions
+import prog8tests.asmgen.helpers.DummyMemsizer
+import prog8tests.asmgen.helpers.DummyStringEncoder
+import prog8tests.asmgen.helpers.ErrorReporterForTests
+import java.nio.file.Path
+
+
+@TestInstance(TestInstance.Lifecycle.PER_CLASS)
+class TestAsmGen6502 {
+
+    private fun createTestProgram(): Program {
+        /*
+main  {
+
+label_outside:
+    uword var_outside
+
+    sub start () {
+        uword localvar = 1234
+        uword tgt
+
+locallabel:
+        tgt = localvar
+        tgt = &locallabel
+        tgt = &var_outside
+        tgt = &label_outside
+        tgt = &main.start.localvar
+        tgt = &main.start.locallabel
+        tgt = &main.var_outside
+        tgt = &main.label_outside
+    }
+}
+
+         */
+        val varInSub = VarDecl(VarDeclType.VAR, DataType.UWORD, ZeropageWish.DONTCARE, null, "localvar", NumericLiteralValue.optimalInteger(1234, Position.DUMMY), false, false, false, Position.DUMMY)
+        val var2InSub = VarDecl(VarDeclType.VAR, DataType.UWORD, ZeropageWish.DONTCARE, null, "tgt", null, false, false, false, Position.DUMMY)
+        val labelInSub = Label("locallabel", Position.DUMMY)
+
+        val tgt = AssignTarget(IdentifierReference(listOf("tgt"), Position.DUMMY), null, null, Position.DUMMY)
+        val assign1 = Assignment(tgt, IdentifierReference(listOf("localvar"), Position.DUMMY), Position.DUMMY)
+        val assign2 = Assignment(tgt, AddressOf(IdentifierReference(listOf("locallabel"), Position.DUMMY), Position.DUMMY), Position.DUMMY)
+        val assign3 = Assignment(tgt, AddressOf(IdentifierReference(listOf("var_outside"), Position.DUMMY), Position.DUMMY), Position.DUMMY)
+        val assign4 = Assignment(tgt, AddressOf(IdentifierReference(listOf("label_outside"), Position.DUMMY), Position.DUMMY), Position.DUMMY)
+        val assign5 = Assignment(tgt, AddressOf(IdentifierReference(listOf("main","start","localvar"), Position.DUMMY), Position.DUMMY), Position.DUMMY)
+        val assign6 = Assignment(tgt, AddressOf(IdentifierReference(listOf("main","start","locallabel"), Position.DUMMY), Position.DUMMY), Position.DUMMY)
+        val assign7 = Assignment(tgt, AddressOf(IdentifierReference(listOf("main","var_outside"), Position.DUMMY), Position.DUMMY), Position.DUMMY)
+        val assign8 = Assignment(tgt, AddressOf(IdentifierReference(listOf("main","label_outside"), Position.DUMMY), Position.DUMMY), Position.DUMMY)
+
+        val statements = mutableListOf(varInSub, var2InSub, labelInSub, assign1, assign2, assign3, assign4, assign5, assign6, assign7, assign8)
+        val subroutine = Subroutine("start", mutableListOf(), emptyList(), emptyList(), emptyList(), emptySet(), null, false, false, statements, Position.DUMMY)
+        val labelInBlock = Label("label_outside", Position.DUMMY)
+        val varInBlock = VarDecl(VarDeclType.VAR, DataType.UWORD, ZeropageWish.DONTCARE, null, "var_outside", null, false, false, false, Position.DUMMY)
+        val block = Block("main", null, mutableListOf(labelInBlock, varInBlock, subroutine), false, Position.DUMMY)
+
+        val module = Module(mutableListOf(block), Position.DUMMY, SourceCode.Generated("test"))
+        val program = Program("test", DummyFunctions, DummyMemsizer, DummyStringEncoder)
+            .addModule(module)
+        module.linkIntoProgram(program)
+        return program
+    }
+
+    private fun createTestAsmGen(program: Program): AsmGen {
+        val errors = ErrorReporterForTests()
+        val options = CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.FULL, emptyList(), false, true, C64Target)
+        val zp = C64MachineDefinition.C64Zeropage(options)
+        val asmgen = AsmGen(program, errors, zp, options, C64Target, Path.of(""))
+        return asmgen
+    }
+
+    @Test
+    fun testSymbolNameFromStrings() {
+        val program = createTestProgram()
+        val asmgen = createTestAsmGen(program)
+
+        assertThat(asmgen.asmSymbolName("name"), equalTo("name"))
+        assertThat(asmgen.asmSymbolName("<name>"), equalTo("prog8_name"))
+        assertThat(asmgen.asmSymbolName(RegisterOrPair.R15), equalTo("cx16.r15"))
+        assertThat(asmgen.asmSymbolName(listOf("a", "b", "name")), equalTo("a.b.name"))
+        assertThat(asmgen.asmVariableName("name"), equalTo("name"))
+        assertThat(asmgen.asmVariableName("<name>"), equalTo("prog8_name"))
+        assertThat(asmgen.asmVariableName(listOf("a", "b", "name")), equalTo("a.b.name"))
+    }
+
+    @Test
+    fun testSymbolNameFromVarIdentifier() {
+        val program = createTestProgram()
+        val asmgen = createTestAsmGen(program)
+        val sub = program.entrypoint
+
+        // local variable
+        val localvarIdent = sub.statements.filterIsInstance<Assignment>().first { it.value is IdentifierReference }.value as IdentifierReference
+        assertThat(asmgen.asmSymbolName(localvarIdent), equalTo("localvar"))
+        assertThat(asmgen.asmVariableName(localvarIdent), equalTo("localvar"))
+        val localvarIdentScoped = (sub.statements.filterIsInstance<Assignment>().first { (it.value as? AddressOf)?.identifier?.nameInSource==listOf("main", "start", "localvar") }.value as AddressOf).identifier
+        assertThat(asmgen.asmSymbolName(localvarIdentScoped), equalTo("main.start.localvar"))
+        assertThat(asmgen.asmVariableName(localvarIdentScoped), equalTo("main.start.localvar"))
+
+        // variable from outer scope (note that for Variables, no scoping prefix symbols are required,
+        //   because they're not outputted as locally scoped symbols for the assembler
+        val scopedVarIdent = (sub.statements.filterIsInstance<Assignment>().first { (it.value as? AddressOf)?.identifier?.nameInSource==listOf("var_outside") }.value as AddressOf).identifier
+        assertThat(asmgen.asmSymbolName(scopedVarIdent), equalTo("main.var_outside"))
+        assertThat(asmgen.asmVariableName(scopedVarIdent), equalTo("var_outside"))
+        val scopedVarIdentScoped = (sub.statements.filterIsInstance<Assignment>().first { (it.value as? AddressOf)?.identifier?.nameInSource==listOf("main", "var_outside") }.value as AddressOf).identifier
+        assertThat(asmgen.asmSymbolName(scopedVarIdentScoped), equalTo("main.var_outside"))
+        assertThat(asmgen.asmVariableName(scopedVarIdentScoped), equalTo("main.var_outside"))
+    }
+
+    @Test
+    fun testSymbolNameFromLabelIdentifier() {
+        val program = createTestProgram()
+        val asmgen = createTestAsmGen(program)
+        val sub = program.entrypoint
+
+        // local label
+        val localLabelIdent = (sub.statements.filterIsInstance<Assignment>().first { (it.value as? AddressOf)?.identifier?.nameInSource==listOf("locallabel") }.value as AddressOf).identifier
+        assertThat(asmgen.asmSymbolName(localLabelIdent), equalTo("_locallabel"))
+        assertThat("as a variable it uses different naming rules (no underscore prefix)", asmgen.asmVariableName(localLabelIdent), equalTo("locallabel"))
+        val localLabelIdentScoped = (sub.statements.filterIsInstance<Assignment>().first { (it.value as? AddressOf)?.identifier?.nameInSource==listOf("main","start","locallabel") }.value as AddressOf).identifier
+        assertThat(asmgen.asmSymbolName(localLabelIdentScoped), equalTo("main.start._locallabel"))
+        assertThat("as a variable it uses different naming rules (no underscore prefix)", asmgen.asmVariableName(localLabelIdentScoped), equalTo("main.start.locallabel"))
+
+        // label from outer scope needs sope prefixes because it is outputted as a locally scoped symbol for the assembler
+        val scopedLabelIdent = (sub.statements.filterIsInstance<Assignment>().first { (it.value as? AddressOf)?.identifier?.nameInSource==listOf("label_outside") }.value as AddressOf).identifier
+        assertThat(asmgen.asmSymbolName(scopedLabelIdent), equalTo("main._label_outside"))
+        assertThat("as a variable it uses different naming rules (no underscore prefix)", asmgen.asmVariableName(scopedLabelIdent), equalTo("label_outside"))
+        val scopedLabelIdentScoped = (sub.statements.filterIsInstance<Assignment>().first { (it.value as? AddressOf)?.identifier?.nameInSource==listOf("main","label_outside") }.value as AddressOf).identifier
+        assertThat(asmgen.asmSymbolName(scopedLabelIdentScoped), equalTo("main._label_outside"))
+        assertThat("as a variable it uses different naming rules (no underscore prefix)", asmgen.asmVariableName(scopedLabelIdentScoped), equalTo("main.label_outside"))
+    }
+}

codeGeneration/test/helpers/Dummies.kt

@@ -0,0 +1,37 @@
+package prog8tests.asmgen.helpers
+
+import prog8.ast.IBuiltinFunctions
+import prog8.ast.base.Position
+import prog8.ast.expressions.Expression
+import prog8.ast.expressions.InferredTypes
+import prog8.ast.expressions.NumericLiteralValue
+import prog8.compilerinterface.IMemSizer
+import prog8.ast.base.DataType
+import prog8.compilerinterface.IStringEncoding
+
+
+internal val DummyFunctions = object : IBuiltinFunctions {
+    override val names: Set<String> = emptySet()
+    override val purefunctionNames: Set<String> = emptySet()
+    override fun constValue(
+        name: String,
+        args: List<Expression>,
+        position: Position,
+    ): NumericLiteralValue? = null
+
+    override fun returnType(name: String, args: MutableList<Expression>) = InferredTypes.InferredType.unknown()
+}
+
+internal val DummyMemsizer = object : IMemSizer {
+    override fun memorySize(dt: DataType): Int = 0
+}
+
+internal val DummyStringEncoder = object : IStringEncoding {
+    override fun encodeString(str: String, altEncoding: Boolean): List<Short> {
+        return emptyList()
+    }
+
+    override fun decodeString(bytes: List<Short>, altEncoding: Boolean): String {
+        return ""
+    }
+}

codeGeneration/test/helpers/ErrorReporterForTests.kt

@@ -0,0 +1,30 @@
+package prog8tests.asmgen.helpers
+
+import prog8.ast.base.Position
+import prog8.compilerinterface.IErrorReporter
+
+internal class ErrorReporterForTests(private val throwExceptionAtReportIfErrors: Boolean=true): IErrorReporter {
+
+
+    val errors = mutableListOf<String>()
+    val warnings = mutableListOf<String>()
+
+    override fun err(msg: String, position: Position) {
+        errors.add("${position.toClickableStr()} $msg")
+    }
+
+    override fun warn(msg: String, position: Position) {
+        warnings.add("${position.toClickableStr()} $msg")
+    }
+
+    override fun noErrors(): Boolean  = errors.isEmpty()
+
+    override fun report() {
+        warnings.forEach { println("UNITTEST COMPILATION REPORT: WARNING: $it") }
+        errors.forEach { println("UNITTEST COMPILATION REPORT: ERROR: $it") }
+        if(throwExceptionAtReportIfErrors)
+            finalizeNumErrors(errors.size, warnings.size)
+        errors.clear()
+        warnings.clear()
+    }
+}

codeOptimizers/build.gradle

@@ -0,0 +1,54 @@
+
+plugins {
+    id 'java'
+    id 'application'
+    id "org.jetbrains.kotlin.jvm"
+}
+
+java {
+    toolchain {
+        languageVersion = JavaLanguageVersion.of(javaVersion)
+    }
+}
+
+dependencies {
+    implementation project(':compilerInterfaces')
+    implementation project(':compilerAst')
+    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8"
+    // implementation "org.jetbrains.kotlin:kotlin-reflect"
+
+    testImplementation "org.jetbrains.kotlin:kotlin-test-junit5"
+    testImplementation 'org.junit.jupiter:junit-jupiter-api:5.7.2'
+    testImplementation 'org.hamcrest:hamcrest:2.2'
+    testRuntimeOnly 'org.junit.jupiter:junit-jupiter-engine:5.7.2'
+
+}
+
+sourceSets {
+    main {
+        java {
+            srcDirs = ["${project.projectDir}/src"]
+        }
+        resources {
+            srcDirs = ["${project.projectDir}/res"]
+        }
+    }
+    test {
+        java {
+            srcDirs = ["${project.projectDir}/test"]
+        }
+    }
+}
+
+test {
+    // Enable JUnit 5 (Gradle 4.6+).
+    useJUnitPlatform()
+
+    // Always run tests, even when nothing changed.
+    dependsOn 'cleanTest'
+
+    // Show test results.
+    testLogging {
+        events "skipped", "failed"
+    }
+}

codeOptimizers/codeOptimizers.iml

@@ -0,0 +1,18 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<module type="JAVA_MODULE" version="4">
+  <component name="NewModuleRootManager" inherit-compiler-output="true">
+    <exclude-output />
+    <content url="file://$MODULE_DIR$">
+      <sourceFolder url="file://$MODULE_DIR$/src" isTestSource="false" />
+      <sourceFolder url="file://$MODULE_DIR$/test" isTestSource="true" />
+      <excludeFolder url="file://$MODULE_DIR$/build" />
+    </content>
+    <orderEntry type="jdk" jdkName="openjdk-11" jdkType="JavaSDK" />
+    <orderEntry type="sourceFolder" forTests="false" />
+    <orderEntry type="library" name="KotlinJavaRuntime" level="project" />
+    <orderEntry type="module" module-name="compilerInterfaces" />
+    <orderEntry type="module" module-name="compilerAst" />
+    <orderEntry type="library" scope="TEST" name="hamcrest" level="project" />
+    <orderEntry type="library" name="junit.jupiter" level="project" />
+  </component>
+</module>

codeOptimizers/src/prog8/optimizer/BinExprSplitter.kt

@@ -1,20 +1,24 @@
 package prog8.optimizer
 
-import prog8.ast.INameScope
+import prog8.ast.IStatementContainer
 import prog8.ast.Node
 import prog8.ast.Program
-import prog8.ast.expressions.*
-import prog8.ast.processing.AstWalker
-import prog8.ast.processing.IAstModification
+import prog8.ast.base.DataType
+import prog8.ast.expressions.BinaryExpression
+import prog8.ast.expressions.augmentAssignmentOperators
 import prog8.ast.statements.AssignTarget
 import prog8.ast.statements.Assignment
+import prog8.ast.walk.AstWalker
+import prog8.ast.walk.IAstModification
+import prog8.compilerinterface.CompilationOptions
+import prog8.compilerinterface.ICompilationTarget
+import prog8.compilerinterface.isInRegularRAMof
 
 
-internal class BinExprSplitter(private val program: Program) : AstWalker() {
-    private val noModifications = emptyList<IAstModification>()
+class BinExprSplitter(private val program: Program, private val options: CompilationOptions, private val compTarget: ICompilationTarget) : AstWalker() {
 
 //    override fun after(decl: VarDecl, parent: Node): Iterable<IAstModification> {
-// TODO somehow if we do this, the resulting code for some programs (cube3d.p8) gets hundreds of bytes larger...:
+// TODO somehow if we do this, the resulting code for some programs (cube3d.p8) gets hundreds of bytes larger...: [ IS THIS STILL TRUE AFTER ALL CHANGES? ]
 //        if(decl.type==VarDeclType.VAR ) {
 //            val binExpr = decl.value as? BinaryExpression
 //            if (binExpr != null && binExpr.operator in augmentAssignmentOperators) {
@@ -36,6 +40,11 @@ internal class BinExprSplitter(private val program: Program) : AstWalker() {
 
         val binExpr = assignment.value as? BinaryExpression
         if (binExpr != null) {
+
+            if(binExpr.inferType(program).istype(DataType.FLOAT) && !options.optimizeFloatExpressions)
+                return noModifications
+
+
 /*
 
 Reduce the complexity of a (binary) expression that has to be evaluated on the eval stack,
@@ -53,17 +62,18 @@ X =      BinExpr                                    X   =   LeftExpr
 
 
  */
-            if(binExpr.operator in augmentAssignmentOperators && isSimpleTarget(assignment.target, program.namespace)) {
+            if(binExpr.operator in augmentAssignmentOperators && isSimpleTarget(assignment.target)) {
                 if(assignment.target isSameAs binExpr.left || assignment.target isSameAs binExpr.right)
                     return noModifications
 
-                if(isSimpleExpression(binExpr.right) && !assignment.isAugmentable) {
-                    val firstAssign = Assignment(assignment.target, binExpr.left, binExpr.left.position)
+                if(binExpr.right.isSimple && !assignment.isAugmentable) {
+                    val firstAssign = Assignment(assignment.target.copy(), binExpr.left, binExpr.left.position)
                     val targetExpr = assignment.target.toExpression()
                     val augExpr = BinaryExpression(targetExpr, binExpr.operator, binExpr.right, binExpr.right.position)
                     return listOf(
-                            IAstModification.InsertBefore(assignment, firstAssign, assignment.definingScope()),
-                            IAstModification.ReplaceNode(assignment.value, augExpr, assignment))
+                        IAstModification.ReplaceNode(binExpr, augExpr, assignment),
+                        IAstModification.InsertBefore(assignment, firstAssign, assignment.parent as IStatementContainer)
+                    )
                 }
             }
 
@@ -75,12 +85,9 @@ X =      BinExpr                                    X   =   LeftExpr
         return noModifications
     }
 
-    private fun isSimpleExpression(expr: Expression) =
-            expr is IdentifierReference || expr is NumericLiteralValue || expr is AddressOf || expr is DirectMemoryRead || expr is StringLiteralValue || expr is ArrayLiteralValue || expr is RangeExpr
-
-    private fun isSimpleTarget(target: AssignTarget, namespace: INameScope) =
+    private fun isSimpleTarget(target: AssignTarget) =
             if (target.identifier!=null || target.memoryAddress!=null)
-                target.isInRegularRAM(namespace)
+                target.isInRegularRAMof(compTarget.machine)
             else
                 false
 

codeOptimizers/src/prog8/optimizer/ConstExprEvaluator.kt

@@ -9,28 +9,32 @@ import kotlin.math.pow
 class ConstExprEvaluator {
 
     fun evaluate(left: NumericLiteralValue, operator: String, right: NumericLiteralValue): Expression {
-        return when(operator) {
-            "+" -> plus(left, right)
-            "-" -> minus(left, right)
-            "*" -> multiply(left, right)
-            "/" -> divide(left, right)
-            "%" -> remainder(left, right)
-            "**" -> power(left, right)
-            "&" -> bitwiseand(left, right)
-            "|" -> bitwiseor(left, right)
-            "^" -> bitwisexor(left, right)
-            "and" -> logicaland(left, right)
-            "or" -> logicalor(left, right)
-            "xor" -> logicalxor(left, right)
-            "<" -> NumericLiteralValue.fromBoolean(left < right, left.position)
-            ">" -> NumericLiteralValue.fromBoolean(left > right, left.position)
-            "<=" -> NumericLiteralValue.fromBoolean(left <= right, left.position)
-            ">=" -> NumericLiteralValue.fromBoolean(left >= right, left.position)
-            "==" -> NumericLiteralValue.fromBoolean(left == right, left.position)
-            "!=" -> NumericLiteralValue.fromBoolean(left != right, left.position)
-            "<<" -> shiftedleft(left, right)
-            ">>" -> shiftedright(left, right)
-            else -> throw FatalAstException("const evaluation for invalid operator $operator")
+        try {
+            return when(operator) {
+                "+" -> plus(left, right)
+                "-" -> minus(left, right)
+                "*" -> multiply(left, right)
+                "/" -> divide(left, right)
+                "%" -> remainder(left, right)
+                "**" -> power(left, right)
+                "&" -> bitwiseand(left, right)
+                "|" -> bitwiseor(left, right)
+                "^" -> bitwisexor(left, right)
+                "and" -> logicaland(left, right)
+                "or" -> logicalor(left, right)
+                "xor" -> logicalxor(left, right)
+                "<" -> NumericLiteralValue.fromBoolean(left < right, left.position)
+                ">" -> NumericLiteralValue.fromBoolean(left > right, left.position)
+                "<=" -> NumericLiteralValue.fromBoolean(left <= right, left.position)
+                ">=" -> NumericLiteralValue.fromBoolean(left >= right, left.position)
+                "==" -> NumericLiteralValue.fromBoolean(left == right, left.position)
+                "!=" -> NumericLiteralValue.fromBoolean(left != right, left.position)
+                "<<" -> shiftedleft(left, right)
+                ">>" -> shiftedright(left, right)
+                else -> throw FatalAstException("const evaluation for invalid operator $operator")
+            }
+        } catch (ax: FatalAstException) {
+            throw ExpressionError(ax.message, left.position)
         }
     }
 

codeOptimizers/src/prog8/optimizer/ConstantFoldingOptimizer.kt

@@ -4,14 +4,15 @@ import prog8.ast.Node
 import prog8.ast.Program
 import prog8.ast.base.*
 import prog8.ast.expressions.*
-import prog8.ast.processing.AstWalker
-import prog8.ast.processing.IAstModification
-import prog8.ast.statements.*
+import prog8.ast.statements.Assignment
+import prog8.ast.statements.ForLoop
+import prog8.ast.statements.VarDecl
+import prog8.ast.walk.AstWalker
+import prog8.ast.walk.IAstModification
 import kotlin.math.pow
 
 
-internal class ConstantFoldingOptimizer(private val program: Program) : AstWalker() {
-    private val noModifications = emptyList<IAstModification>()
+class ConstantFoldingOptimizer(private val program: Program) : AstWalker() {
 
     override fun before(memread: DirectMemoryRead, parent: Node): Iterable<IAstModification> {
         // @( &thing )  -->  thing
@@ -104,7 +105,7 @@ internal class ConstantFoldingOptimizer(private val program: Program) : AstWalke
             // optimize various simple cases of ** :
             //  optimize away 1 ** x into just 1 and 0 ** x into just 0
             //  optimize 2 ** x into (1<<x)  if both operands are integer.
-            val leftDt = leftconst.inferType(program).typeOrElse(DataType.STRUCT)
+            val leftDt = leftconst.inferType(program).getOr(DataType.UNDEFINED)
             when (leftconst.number.toDouble()) {
                 0.0 -> {
                     val value = NumericLiteralValue(leftDt, 0, expr.position)
@@ -119,11 +120,11 @@ internal class ConstantFoldingOptimizer(private val program: Program) : AstWalke
                         val value = NumericLiteralValue(leftDt, 2.0.pow(rightconst.number.toDouble()), expr.position)
                         modifications += IAstModification.ReplaceNode(expr, value, parent)
                     } else {
-                        val rightDt = expr.right.inferType(program).typeOrElse(DataType.STRUCT)
+                        val rightDt = expr.right.inferType(program).getOr(DataType.UNDEFINED)
                         if(leftDt in IntegerDatatypes && rightDt in IntegerDatatypes) {
                             val targetDt =
                                 when (parent) {
-                                    is Assignment -> parent.target.inferType(program).typeOrElse(DataType.STRUCT)
+                                    is Assignment -> parent.target.inferType(program).getOr(DataType.UNDEFINED)
                                     is VarDecl -> parent.datatype
                                     else -> leftDt
                                 }
@@ -136,7 +137,7 @@ internal class ConstantFoldingOptimizer(private val program: Program) : AstWalke
             }
         }
 
-        if(expr.inferType(program).istype(DataType.FLOAT)) {
+        if(expr.inferType(program) istype DataType.FLOAT) {
             val subExpr: BinaryExpression? = when {
                 leftconst != null -> expr.right as? BinaryExpression
                 rightconst != null -> expr.left as? BinaryExpression
@@ -185,7 +186,7 @@ internal class ConstantFoldingOptimizer(private val program: Program) : AstWalke
         } else {
             val arrayDt = array.guessDatatype(program)
             if (arrayDt.isKnown) {
-                val newArray = array.cast(arrayDt.typeOrElse(DataType.STRUCT))
+                val newArray = array.cast(arrayDt.getOr(DataType.UNDEFINED))
                 if (newArray != null && newArray != array)
                     return listOf(IAstModification.ReplaceNode(array, newArray, parent))
             }
@@ -230,7 +231,7 @@ internal class ConstantFoldingOptimizer(private val program: Program) : AstWalke
         val rangeTo = iterableRange.to as? NumericLiteralValue
         if(rangeFrom==null || rangeTo==null) return noModifications
 
-        val loopvar = forLoop.loopVar.targetVarDecl(program.namespace) ?: throw UndefinedSymbolError(forLoop.loopVar)
+        val loopvar = forLoop.loopVar.targetVarDecl(program) ?: throw UndefinedSymbolError(forLoop.loopVar)
 
         val stepLiteral = iterableRange.step as? NumericLiteralValue
         when(loopvar.datatype) {
@@ -276,7 +277,7 @@ internal class ConstantFoldingOptimizer(private val program: Program) : AstWalke
         val numval = decl.value as? NumericLiteralValue
         if(decl.type== VarDeclType.CONST && numval!=null) {
             val valueDt = numval.inferType(program)
-            if(!valueDt.istype(decl.datatype)) {
+            if(valueDt isnot decl.datatype) {
                 val cast = numval.cast(decl.datatype)
                 if(cast.isValid)
                     return listOf(IAstModification.ReplaceNode(numval, cast.valueOrZero(), decl))

codeOptimizers/src/prog8/optimizer/ConstantIdentifierReplacer.kt

@@ -4,23 +4,27 @@ import prog8.ast.Node
 import prog8.ast.Program
 import prog8.ast.base.*
 import prog8.ast.expressions.*
-import prog8.ast.processing.AstWalker
-import prog8.ast.processing.IAstModification
-import prog8.ast.statements.ArrayIndex
-import prog8.ast.statements.AssignTarget
-import prog8.ast.statements.ForLoop
-import prog8.ast.statements.VarDecl
-import prog8.compiler.target.CompilationTarget
+import prog8.ast.statements.*
+import prog8.ast.walk.AstWalker
+import prog8.ast.walk.IAstModification
+import prog8.compilerinterface.ICompilationTarget
+import prog8.compilerinterface.IErrorReporter
+import prog8.compilerinterface.size
+import prog8.compilerinterface.toConstantIntegerRange
 
 // Fix up the literal value's type to match that of the vardecl
-internal class VarConstantValueTypeAdjuster(private val program: Program, private val errors: ErrorReporter) : AstWalker() {
-    private val noModifications = emptyList<IAstModification>()
+//   (also check range literal operands types before they get expanded into arrays for instance)
+class VarConstantValueTypeAdjuster(private val program: Program, private val errors: IErrorReporter) : AstWalker() {
 
     override fun after(decl: VarDecl, parent: Node): Iterable<IAstModification> {
+
+        if(decl.parent is AnonymousScope)
+            throw FatalAstException("vardecl may no longer occur in anonymousscope")
+
         try {
             val declConstValue = decl.value?.constValue(program)
             if(declConstValue!=null && (decl.type==VarDeclType.VAR || decl.type==VarDeclType.CONST)
-                && !declConstValue.inferType(program).istype(decl.datatype)) {
+                && declConstValue.inferType(program) isnot decl.datatype) {
                 // cast the numeric literal to the appropriate datatype of the variable
                 val cast = declConstValue.cast(decl.datatype)
                 if(cast.isValid)
@@ -32,14 +36,42 @@ internal class VarConstantValueTypeAdjuster(private val program: Program, privat
 
         return noModifications
     }
+
+    override fun after(range: RangeExpr, parent: Node): Iterable<IAstModification> {
+        val from = range.from.constValue(program)?.number?.toDouble()
+        val to = range.to.constValue(program)?.number?.toDouble()
+        val step = range.step.constValue(program)?.number?.toDouble()
+
+        if(from==null) {
+            if(!range.from.inferType(program).isInteger)
+                errors.err("range expression from value must be integer", range.from.position)
+        } else if(from-from.toInt()>0) {
+            errors.err("range expression from value must be integer", range.from.position)
+        }
+
+        if(to==null) {
+            if(!range.to.inferType(program).isInteger)
+                errors.err("range expression to value must be integer", range.to.position)
+        } else if(to-to.toInt()>0) {
+            errors.err("range expression to value must be integer", range.to.position)
+        }
+
+        if(step==null) {
+            if(!range.step.inferType(program).isInteger)
+                errors.err("range expression step value must be integer", range.step.position)
+        } else if(step-step.toInt()>0) {
+            errors.err("range expression step value must be integer", range.step.position)
+        }
+
+        return noModifications
+    }
 }
 
 
 // Replace all constant identifiers with their actual value,
 // and the array var initializer values and sizes.
 // This is needed because further constant optimizations depend on those.
-internal class ConstantIdentifierReplacer(private val program: Program, private val errors: ErrorReporter) : AstWalker() {
-    private val noModifications = emptyList<IAstModification>()
+internal class ConstantIdentifierReplacer(private val program: Program, private val errors: IErrorReporter, private val compTarget: ICompilationTarget) : AstWalker() {
 
     override fun after(identifier: IdentifierReference, parent: Node): Iterable<IAstModification> {
         // replace identifiers that refer to const value, with the value itself
@@ -74,7 +106,7 @@ internal class ConstantIdentifierReplacer(private val program: Program, private
     override fun before(decl: VarDecl, parent: Node): Iterable<IAstModification> {
         // the initializer value can't refer to the variable itself (recursive definition)
         // TODO: use call graph for this?
-        if(decl.value?.referencesIdentifier(decl.name) == true || decl.arraysize?.indexVar?.referencesIdentifier(decl.name) == true) {
+        if(decl.value?.referencesIdentifier(decl.name) == true || decl.arraysize?.indexExpr?.referencesIdentifier(decl.name) == true) {
             errors.err("recursive var declaration", decl.position)
             return noModifications
         }
@@ -92,19 +124,6 @@ internal class ConstantIdentifierReplacer(private val program: Program, private
                                 decl
                         ))
                     }
-                } else if(arraysize.constIndex()==null) {
-                    // see if we can calculate the size from other fields
-                    try {
-                        val cval =  arraysize.indexVar?.constValue(program) ?: arraysize.origExpression?.constValue(program)
-                        if (cval != null) {
-                            arraysize.indexVar = null
-                            arraysize.origExpression = null
-                            arraysize.indexNum = cval
-                        }
-                    } catch (x: UndefinedSymbolError) {
-                        errors.err(x.message, x.position)
-                        return noModifications
-                    }
                 }
             }
 
@@ -118,7 +137,6 @@ internal class ConstantIdentifierReplacer(private val program: Program, private
                     }
                 }
                 DataType.ARRAY_UB, DataType.ARRAY_B, DataType.ARRAY_UW, DataType.ARRAY_W -> {
-                    val numericLv = decl.value as? NumericLiteralValue
                     val rangeExpr = decl.value as? RangeExpr
                     if(rangeExpr!=null) {
                         // convert the initializer range expression to an actual array
@@ -127,7 +145,7 @@ internal class ConstantIdentifierReplacer(private val program: Program, private
                             errors.err("range expression size doesn't match declared array size", decl.value?.position!!)
                         val constRange = rangeExpr.toConstantIntegerRange()
                         if(constRange!=null) {
-                            val eltType = rangeExpr.inferType(program).typeOrElse(DataType.UBYTE)
+                            val eltType = rangeExpr.inferType(program).getOr(DataType.UBYTE)
                             val newValue = if(eltType in ByteDatatypes) {
                                 ArrayLiteralValue(InferredTypes.InferredType.known(decl.datatype),
                                         constRange.map { NumericLiteralValue(eltType, it.toShort(), decl.value!!.position) }.toTypedArray(),
@@ -140,6 +158,7 @@ internal class ConstantIdentifierReplacer(private val program: Program, private
                             return listOf(IAstModification.ReplaceNode(decl.value!!, newValue, decl))
                         }
                     }
+                    val numericLv = decl.value as? NumericLiteralValue
                     if(numericLv!=null && numericLv.type== DataType.FLOAT)
                         errors.err("arraysize requires only integers here", numericLv.position)
                     val size = decl.arraysize?.constIndex() ?: return noModifications
@@ -166,20 +185,18 @@ internal class ConstantIdentifierReplacer(private val program: Program, private
                             else -> {}
                         }
                         // create the array itself, filled with the fillvalue.
-                        val array = Array(size) {fillvalue}.map { NumericLiteralValue(ArrayElementTypes.getValue(decl.datatype), it, numericLv.position) }.toTypedArray<Expression>()
+                        val array = Array(size) {fillvalue}.map { NumericLiteralValue(ArrayToElementTypes.getValue(decl.datatype), it, numericLv.position) }.toTypedArray<Expression>()
                         val refValue = ArrayLiteralValue(InferredTypes.InferredType.known(decl.datatype), array, position = numericLv.position)
                         return listOf(IAstModification.ReplaceNode(decl.value!!, refValue, decl))
                     }
                 }
                 DataType.ARRAY_F -> {
-                    val size = decl.arraysize?.constIndex() ?: return noModifications
-                    val litval = decl.value as? NumericLiteralValue
                     val rangeExpr = decl.value as? RangeExpr
                     if(rangeExpr!=null) {
                         // convert the initializer range expression to an actual array of floats
                         val declArraySize = decl.arraysize?.constIndex()
                         if(declArraySize!=null && declArraySize!=rangeExpr.size())
-                            errors.err("range expression size doesn't match declared array size", decl.value?.position!!)
+                            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 = ArrayLiteralValue(InferredTypes.InferredType.known(DataType.ARRAY_F),
@@ -188,22 +205,24 @@ internal class ConstantIdentifierReplacer(private val program: Program, private
                             return listOf(IAstModification.ReplaceNode(decl.value!!, newValue, decl))
                         }
                     }
-                    if(rangeExpr==null && litval!=null) {
+
+                    val numericLv = decl.value as? NumericLiteralValue
+                    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 = litval.number.toDouble()
-                        if (fillvalue < CompilationTarget.instance.machine.FLOAT_MAX_NEGATIVE || fillvalue > CompilationTarget.instance.machine.FLOAT_MAX_POSITIVE)
-                            errors.err("float value overflow", litval.position)
+                        val fillvalue = numericLv.number.toDouble()
+                        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 { NumericLiteralValue(DataType.FLOAT, it, litval.position) }.toTypedArray<Expression>()
-                            val refValue = ArrayLiteralValue(InferredTypes.InferredType.known(DataType.ARRAY_F), array, position = litval.position)
+                            val array = Array(size) {fillvalue}.map { NumericLiteralValue(DataType.FLOAT, it, numericLv.position) }.toTypedArray<Expression>()
+                            val refValue = ArrayLiteralValue(InferredTypes.InferredType.known(DataType.ARRAY_F), array, position = numericLv.position)
                             return listOf(IAstModification.ReplaceNode(decl.value!!, refValue, decl))
                         }
                     }
                 }
                 else -> {
                     // nothing to do for this type
-                    // this includes strings and structs
                 }
             }
         }

codeOptimizers/src/prog8/optimizer/ExpressionSimplifier.kt

@@ -2,27 +2,40 @@ package prog8.optimizer
 
 import prog8.ast.Node
 import prog8.ast.Program
-import prog8.ast.base.*
+import prog8.ast.base.DataType
+import prog8.ast.base.FatalAstException
+import prog8.ast.base.IntegerDatatypes
+import prog8.ast.base.NumericDatatypes
 import prog8.ast.expressions.*
-import prog8.ast.processing.AstWalker
-import prog8.ast.processing.IAstModification
 import prog8.ast.statements.Assignment
+import prog8.ast.walk.AstWalker
+import prog8.ast.walk.IAstModification
 import kotlin.math.abs
 import kotlin.math.log2
 import kotlin.math.pow
 
 /*
-    todo add more expression optimizations
+    todo add more peephole expression optimizations
 
     Investigate what optimizations binaryen has, also see  https://egorbo.com/peephole-optimizations.html
 
+*(&X)  =>  X
+X % 1  => 0
+X / 1  =>  X
+X ^ -1  =>  ~x
+X >= 1  =>  X > 0
+X <  1  =>  X <= 0
+X + С1 == C2  =>  X == C2 - C1
+((X + C1) + C2)  =>  (X + (C1 + C2))
+((X + C1) + (Y + C2))  =>  ((X + Y) + (C1 + C2))
+
+
  */
 
 
-internal class ExpressionSimplifier(private val program: Program) : AstWalker() {
+class ExpressionSimplifier(private val program: Program) : AstWalker() {
     private val powersOfTwo = (1..16).map { (2.0).pow(it) }.toSet()
     private val negativePowersOfTwo = powersOfTwo.map { -it }.toSet()
-    private val noModifications = emptyList<IAstModification>()
 
     override fun after(typecast: TypecastExpression, parent: Node): Iterable<IAstModification> {
         val mods = mutableListOf<IAstModification>()
@@ -43,7 +56,7 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
                 mods += IAstModification.ReplaceNode(typecast.expression, subTypecast.expression, typecast)
             }
         } else {
-            if (typecast.expression.inferType(program).istype(typecast.type)) {
+            if (typecast.expression.inferType(program) istype typecast.type) {
                 // remove duplicate cast
                 mods += IAstModification.ReplaceNode(typecast, typecast.expression, parent)
             }
@@ -132,8 +145,8 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
             ))
         }
 
-        val leftDt = leftIDt.typeOrElse(DataType.STRUCT)
-        val rightDt = rightIDt.typeOrElse(DataType.STRUCT)
+        val leftDt = leftIDt.getOr(DataType.UNDEFINED)
+        val rightDt = rightIDt.getOr(DataType.UNDEFINED)
 
         if (expr.operator == "+" || expr.operator == "-"
                 && leftVal == null && rightVal == null
@@ -287,13 +300,13 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
             val arg = functionCall.args[0]
             if(arg is TypecastExpression) {
                 val valueDt = arg.expression.inferType(program)
-                if (valueDt.istype(DataType.BYTE) || valueDt.istype(DataType.UBYTE)) {
-                    // useless lsb() of byte value that was casted to word
+                if (valueDt istype DataType.BYTE || valueDt istype DataType.UBYTE) {
+                    // useless lsb() of byte value that was typecasted to word
                     return listOf(IAstModification.ReplaceNode(functionCall, arg.expression, parent))
                 }
             } else {
                 val argDt = arg.inferType(program)
-                if (argDt.istype(DataType.BYTE) || argDt.istype(DataType.UBYTE)) {
+                if (argDt istype DataType.BYTE || argDt istype DataType.UBYTE) {
                     // useless lsb() of byte value
                     return listOf(IAstModification.ReplaceNode(functionCall, arg, parent))
                 }
@@ -303,20 +316,20 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
             val arg = functionCall.args[0]
             if(arg is TypecastExpression) {
                 val valueDt = arg.expression.inferType(program)
-                if (valueDt.istype(DataType.BYTE) || valueDt.istype(DataType.UBYTE)) {
-                    // useless msb() of byte value that was casted to word, replace with 0
+                if (valueDt istype DataType.BYTE || valueDt istype DataType.UBYTE) {
+                    // useless msb() of byte value that was typecasted to word, replace with 0
                     return listOf(IAstModification.ReplaceNode(
                             functionCall,
-                            NumericLiteralValue(valueDt.typeOrElse(DataType.UBYTE), 0, arg.expression.position),
+                            NumericLiteralValue(valueDt.getOr(DataType.UBYTE), 0, arg.expression.position),
                             parent))
                 }
             } else {
                 val argDt = arg.inferType(program)
-                if (argDt.istype(DataType.BYTE) || argDt.istype(DataType.UBYTE)) {
+                if (argDt istype DataType.BYTE || argDt istype DataType.UBYTE) {
                     // useless msb() of byte value, replace with 0
                     return listOf(IAstModification.ReplaceNode(
                             functionCall,
-                            NumericLiteralValue(argDt.typeOrElse(DataType.UBYTE), 0, arg.position),
+                            NumericLiteralValue(argDt.getOr(DataType.UBYTE), 0, arg.position),
                             parent))
                 }
             }
@@ -487,10 +500,10 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
                     val idt = expr.inferType(program)
                     if(!idt.isKnown)
                         throw FatalAstException("unknown dt")
-                    return NumericLiteralValue(idt.typeOrElse(DataType.STRUCT), 0, expr.position)
-                } else if (cv == 2.0) {
+                    return NumericLiteralValue(idt.getOr(DataType.UNDEFINED), 0, expr.position)
+                } else if (cv in powersOfTwo) {
                     expr.operator = "&"
-                    expr.right = NumericLiteralValue.optimalInteger(1, expr.position)
+                    expr.right = NumericLiteralValue.optimalInteger(cv!!.toInt()-1, expr.position)
                     return null
                 }
             }
@@ -511,7 +524,7 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
             val leftIDt = expr.left.inferType(program)
             if (!leftIDt.isKnown)
                 return null
-            val leftDt = leftIDt.typeOrElse(DataType.STRUCT)
+            val leftDt = leftIDt.getOr(DataType.UNDEFINED)
             when (cv) {
                 -1.0 -> {
                     //  '/' -> -left
@@ -588,14 +601,14 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
                     return expr2.left
                 }
                 in powersOfTwo -> {
-                    if (leftValue.inferType(program).typeOrElse(DataType.STRUCT) in IntegerDatatypes) {
+                    if (leftValue.inferType(program).isInteger) {
                         // times a power of two => shift left
                         val numshifts = log2(cv).toInt()
                         return BinaryExpression(expr2.left, "<<", NumericLiteralValue.optimalInteger(numshifts, expr.position), expr.position)
                     }
                 }
                 in negativePowersOfTwo -> {
-                    if (leftValue.inferType(program).typeOrElse(DataType.STRUCT) in IntegerDatatypes) {
+                    if (leftValue.inferType(program).isInteger) {
                         // times a negative power of two => negate, then shift left
                         val numshifts = log2(-cv).toInt()
                         return BinaryExpression(PrefixExpression("-", expr2.left, expr.position), "<<", NumericLiteralValue.optimalInteger(numshifts, expr.position), expr.position)
@@ -619,7 +632,7 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
         val targetIDt = expr.left.inferType(program)
         if(!targetIDt.isKnown)
             throw FatalAstException("unknown dt")
-        when (val targetDt = targetIDt.typeOrElse(DataType.STRUCT)) {
+        when (val targetDt = targetIDt.getOr(DataType.UNDEFINED)) {
             DataType.UBYTE, DataType.BYTE -> {
                 if (amount >= 8) {
                     return NumericLiteralValue(targetDt, 0, expr.position)
@@ -654,7 +667,7 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
         val idt = expr.left.inferType(program)
         if(!idt.isKnown)
             throw FatalAstException("unknown dt")
-        when (idt.typeOrElse(DataType.STRUCT)) {
+        when (idt.getOr(DataType.UNDEFINED)) {
             DataType.UBYTE -> {
                 if (amount >= 8) {
                     return NumericLiteralValue.optimalInteger(0, expr.position)

codeOptimizers/src/prog8/optimizer/Extensions.kt

@@ -1,31 +1,34 @@
 package prog8.optimizer
 
+import prog8.ast.IBuiltinFunctions
 import prog8.ast.Program
-import prog8.ast.base.ErrorReporter
+import prog8.compilerinterface.CompilationOptions
+import prog8.compilerinterface.ICompilationTarget
+import prog8.compilerinterface.IErrorReporter
 
 
-internal fun Program.constantFold(errors: ErrorReporter) {
+fun Program.constantFold(errors: IErrorReporter, compTarget: ICompilationTarget) {
     val valuetypefixer = VarConstantValueTypeAdjuster(this, errors)
     valuetypefixer.visit(this)
-    if(errors.isEmpty()) {
+    if(errors.noErrors()) {
         valuetypefixer.applyModifications()
 
-        val replacer = ConstantIdentifierReplacer(this, errors)
+        val replacer = ConstantIdentifierReplacer(this, errors, compTarget)
         replacer.visit(this)
-        if (errors.isEmpty()) {
+        if (errors.noErrors()) {
             replacer.applyModifications()
 
             valuetypefixer.visit(this)
-            if(errors.isEmpty()) {
+            if(errors.noErrors()) {
                 valuetypefixer.applyModifications()
 
                 val optimizer = ConstantFoldingOptimizer(this)
                 optimizer.visit(this)
-                while (errors.isEmpty() && optimizer.applyModifications() > 0) {
+                while (errors.noErrors() && optimizer.applyModifications() > 0) {
                     optimizer.visit(this)
                 }
 
-                if (errors.isEmpty()) {
+                if (errors.noErrors()) {
                     replacer.visit(this)
                     replacer.applyModifications()
                 }
@@ -33,13 +36,16 @@ internal fun Program.constantFold(errors: ErrorReporter) {
         }
     }
 
-    if(errors.isEmpty())
+    if(errors.noErrors())
         modules.forEach { it.linkParents(namespace) }   // re-link in final configuration
 }
 
 
-internal fun Program.optimizeStatements(errors: ErrorReporter): Int {
-    val optimizer = StatementOptimizer(this, errors)
+fun Program.optimizeStatements(errors: IErrorReporter,
+                               functions: IBuiltinFunctions,
+                               compTarget: ICompilationTarget
+): Int {
+    val optimizer = StatementOptimizer(this, errors, functions, compTarget)
     optimizer.visit(this)
     val optimizationCount = optimizer.applyModifications()
 
@@ -48,14 +54,14 @@ internal fun Program.optimizeStatements(errors: ErrorReporter): Int {
     return optimizationCount
 }
 
-internal fun Program.simplifyExpressions() : Int {
+fun Program.simplifyExpressions() : Int {
     val opti = ExpressionSimplifier(this)
     opti.visit(this)
     return opti.applyModifications()
 }
 
-internal fun Program.splitBinaryExpressions() : Int {
-    val opti = BinExprSplitter(this)
+fun Program.splitBinaryExpressions(options: CompilationOptions, compTarget: ICompilationTarget) : Int {
+    val opti = BinExprSplitter(this, options, compTarget)
     opti.visit(this)
     return opti.applyModifications()
 }

codeOptimizers/src/prog8/optimizer/StatementOptimizer.kt

@@ -1,159 +1,163 @@
 package prog8.optimizer
 
-import prog8.ast.INameScope
+import prog8.ast.IBuiltinFunctions
+import prog8.ast.IStatementContainer
 import prog8.ast.Node
 import prog8.ast.Program
 import prog8.ast.base.*
 import prog8.ast.expressions.*
-import prog8.ast.processing.AstWalker
-import prog8.ast.processing.IAstModification
-import prog8.ast.processing.IAstVisitor
 import prog8.ast.statements.*
-import prog8.compiler.target.CompilationTarget
-import prog8.functions.BuiltinFunctions
+import prog8.ast.walk.AstWalker
+import prog8.ast.walk.IAstModification
+import prog8.ast.walk.IAstVisitor
+import prog8.compilerinterface.ICompilationTarget
+import prog8.compilerinterface.IErrorReporter
+import prog8.compilerinterface.size
 import kotlin.math.floor
 
+internal const val retvarName = "prog8_retval"
 
-internal class StatementOptimizer(private val program: Program,
-                                  private val errors: ErrorReporter) : AstWalker() {
 
-    private val noModifications = emptyList<IAstModification>()
-    private val callgraph = CallGraph(program)
-    private val pureBuiltinFunctions = BuiltinFunctions.filter { it.value.pure }
+class StatementOptimizer(private val program: Program,
+                                  private val errors: IErrorReporter,
+                                  private val functions: IBuiltinFunctions,
+                                  private val compTarget: ICompilationTarget
+) : AstWalker() {
 
-    override fun after(block: Block, parent: Node): Iterable<IAstModification> {
-        if("force_output" !in block.options()) {
-            if (block.containsNoCodeNorVars()) {
-                errors.warn("removing empty block '${block.name}'", block.position)
-                return listOf(IAstModification.Remove(block, parent as INameScope))
-            }
+    private val subsThatNeedReturnVariable = mutableSetOf<Triple<IStatementContainer, DataType, Position>>()
 
-            if (block !in callgraph.usedSymbols) {
-                errors.warn("removing unused block '${block.name}'", block.position)
-                return listOf(IAstModification.Remove(block, parent as INameScope))
-            }
-        }
-        return noModifications
-    }
 
     override fun after(subroutine: Subroutine, parent: Node): Iterable<IAstModification> {
-        val forceOutput = "force_output" in subroutine.definingBlock().options()
-        if(subroutine.asmAddress==null && !forceOutput) {
-            if(subroutine.containsNoCodeNorVars() && !subroutine.inline) {
-                errors.warn("removing empty subroutine '${subroutine.name}'", subroutine.position)
-                val removals = callgraph.calledBy.getValue(subroutine).map {
-                    IAstModification.Remove(it, it.definingScope())
-                }.toMutableList()
-                removals += IAstModification.Remove(subroutine, subroutine.definingScope())
-                return removals
-            }
+        for(returnvar in subsThatNeedReturnVariable) {
+            val decl = VarDecl(VarDeclType.VAR, returnvar.second, ZeropageWish.DONTCARE, null, retvarName, null,
+                isArray = false,
+                autogeneratedDontRemove = true,
+                sharedWithAsm = false,
+                position = returnvar.third
+            )
+            returnvar.first.statements.add(0, decl)
         }
-
-        if(subroutine !in callgraph.usedSymbols && !forceOutput) {
-            errors.warn("removing unused subroutine '${subroutine.name}'", subroutine.position)
-            return listOf(IAstModification.Remove(subroutine, subroutine.definingScope()))
-        }
-
+        subsThatNeedReturnVariable.clear()
         return noModifications
     }
 
-    override fun after(decl: VarDecl, parent: Node): Iterable<IAstModification> {
-        val forceOutput = "force_output" in decl.definingBlock().options()
-        if(decl !in callgraph.usedSymbols && !forceOutput) {
-            if(decl.type == VarDeclType.VAR)
-                errors.warn("removing unused variable '${decl.name}'", decl.position)
-
-            return listOf(IAstModification.Remove(decl, decl.definingScope()))
+    override fun before(functionCall: FunctionCall, parent: Node): Iterable<IAstModification> {
+        // if the first instruction in the called subroutine is a return statement with a simple value,
+        // remove the jump altogeter and inline the returnvalue directly.
+        val subroutine = functionCall.target.targetSubroutine(program)
+        if(subroutine!=null) {
+            val first = subroutine.statements.asSequence().filterNot { it is VarDecl || it is Directive }.firstOrNull()
+            if(first is Return && first.value?.isSimple==true) {
+                val copy = when(val orig = first.value!!) {
+                    is AddressOf -> {
+                        val scoped = scopePrefix(orig.identifier, subroutine)
+                        AddressOf(scoped, orig.position)
+                    }
+                    is DirectMemoryRead -> {
+                        when(val expr = orig.addressExpression) {
+                            is NumericLiteralValue -> DirectMemoryRead(expr.copy(), orig.position)
+                            else -> return noModifications
+                        }
+                    }
+                    is IdentifierReference -> scopePrefix(orig, subroutine)
+                    is NumericLiteralValue -> orig.copy()
+                    is StringLiteralValue -> orig.copy()
+                    else -> return noModifications
+                }
+                return listOf(IAstModification.ReplaceNode(functionCall, copy, parent))
+            }
         }
-
         return noModifications
     }
 
+    private fun scopePrefix(variable: IdentifierReference, subroutine: Subroutine): IdentifierReference {
+        val scoped = subroutine.makeScopedName(variable.nameInSource.last())
+        return IdentifierReference(scoped.split('.'), variable.position)
+    }
+
     override fun after(functionCallStatement: FunctionCallStatement, parent: Node): Iterable<IAstModification> {
-        if(functionCallStatement.target.nameInSource.size==1 && functionCallStatement.target.nameInSource[0] in BuiltinFunctions) {
+        if(functionCallStatement.target.nameInSource.size==1 && functionCallStatement.target.nameInSource[0] in functions.names) {
             val functionName = functionCallStatement.target.nameInSource[0]
-            if (functionName in pureBuiltinFunctions) {
+            if (functionName in functions.purefunctionNames) {
                 errors.warn("statement has no effect (function return value is discarded)", functionCallStatement.position)
-                return listOf(IAstModification.Remove(functionCallStatement, functionCallStatement.definingScope()))
+                return listOf(IAstModification.Remove(functionCallStatement, parent as IStatementContainer))
             }
         }
 
         // printing a literal string of just 2 or 1 characters is replaced by directly outputting those characters
-        // this is a C-64 specific optimization
-        if(functionCallStatement.target.nameInSource==listOf("c64scr", "print")) {
+        // only do this optimization if the arg is a known-constant string literal instead of a user defined variable.
+        if(functionCallStatement.target.nameInSource==listOf("txt", "print")) {
             val arg = functionCallStatement.args.single()
-            val stringVar: IdentifierReference?
-            stringVar = if(arg is AddressOf) {
+            val stringVar: IdentifierReference? = if(arg is AddressOf) {
                 arg.identifier
             } else {
                 arg as? IdentifierReference
             }
-            if(stringVar!=null) {
-                val vardecl = stringVar.targetVarDecl(program.namespace)!!
-                val string = vardecl.value as? StringLiteralValue
+            if(stringVar!=null && stringVar.wasStringLiteral(program)) {
+                val string = stringVar.targetVarDecl(program)?.value as? StringLiteralValue
                 if(string!=null) {
                     val pos = functionCallStatement.position
                     if (string.value.length == 1) {
-                        val firstCharEncoded = CompilationTarget.instance.encodeString(string.value, string.altEncoding)[0]
+                        val firstCharEncoded = compTarget.encodeString(string.value, string.altEncoding)[0]
                         val chrout = FunctionCallStatement(
-                                IdentifierReference(listOf("c64", "CHROUT"), pos),
-                                mutableListOf(NumericLiteralValue(DataType.UBYTE, firstCharEncoded.toInt(), pos)),
-                                functionCallStatement.void, pos
+                            IdentifierReference(listOf("txt", "chrout"), pos),
+                            mutableListOf(NumericLiteralValue(DataType.UBYTE, firstCharEncoded.toInt(), pos)),
+                            functionCallStatement.void, pos
                         )
                         return listOf(IAstModification.ReplaceNode(functionCallStatement, chrout, parent))
                     } else if (string.value.length == 2) {
-                        val firstTwoCharsEncoded = CompilationTarget.instance.encodeString(string.value.take(2), string.altEncoding)
+                        val firstTwoCharsEncoded = compTarget.encodeString(string.value.take(2), string.altEncoding)
                         val chrout1 = FunctionCallStatement(
-                                IdentifierReference(listOf("c64", "CHROUT"), pos),
-                                mutableListOf(NumericLiteralValue(DataType.UBYTE, firstTwoCharsEncoded[0].toInt(), pos)),
-                                functionCallStatement.void, pos
+                            IdentifierReference(listOf("txt", "chrout"), pos),
+                            mutableListOf(NumericLiteralValue(DataType.UBYTE, firstTwoCharsEncoded[0].toInt(), pos)),
+                            functionCallStatement.void, pos
                         )
                         val chrout2 = FunctionCallStatement(
-                                IdentifierReference(listOf("c64", "CHROUT"), pos),
-                                mutableListOf(NumericLiteralValue(DataType.UBYTE, firstTwoCharsEncoded[1].toInt(), pos)),
-                                functionCallStatement.void, pos
+                            IdentifierReference(listOf("txt", "chrout"), pos),
+                            mutableListOf(NumericLiteralValue(DataType.UBYTE, firstTwoCharsEncoded[1].toInt(), pos)),
+                            functionCallStatement.void, pos
+                        )
+                        return listOf(
+                            IAstModification.InsertBefore(functionCallStatement, chrout1, parent as IStatementContainer),
+                            IAstModification.ReplaceNode(functionCallStatement, chrout2, parent)
                         )
-                        val anonscope = AnonymousScope(mutableListOf(), pos)
-                        anonscope.statements.add(chrout1)
-                        anonscope.statements.add(chrout2)
-                        return listOf(IAstModification.ReplaceNode(functionCallStatement, anonscope, parent))
                     }
                 }
             }
         }
 
         // if the first instruction in the called subroutine is a return statement, remove the jump altogeter
-        val subroutine = functionCallStatement.target.targetSubroutine(program.namespace)
+        val subroutine = functionCallStatement.target.targetSubroutine(program)
         if(subroutine!=null) {
             val first = subroutine.statements.asSequence().filterNot { it is VarDecl || it is Directive }.firstOrNull()
             if(first is Return)
-                return listOf(IAstModification.Remove(functionCallStatement, functionCallStatement.definingScope()))
+                return listOf(IAstModification.Remove(functionCallStatement, parent as IStatementContainer))
         }
 
         return noModifications
     }
 
-    override fun before(functionCall: FunctionCall, parent: Node): Iterable<IAstModification> {
-        // if the first instruction in the called subroutine is a return statement with constant value, replace with the constant value
-        val subroutine = functionCall.target.targetSubroutine(program.namespace)
-        if(subroutine!=null) {
-            val first = subroutine.statements.asSequence().filterNot { it is VarDecl || it is Directive }.firstOrNull()
-            if(first is Return && first.value!=null) {
-                val constval = first.value?.constValue(program)
-                if(constval!=null)
-                    return listOf(IAstModification.ReplaceNode(functionCall, constval, parent))
-            }
-        }
-        return noModifications
-    }
+//    override fun before(functionCall: FunctionCall, parent: Node): Iterable<IAstModification> {
+//        // if the first instruction in the called subroutine is a return statement with constant value, replace with the constant value
+//        val subroutine = functionCall.target.targetSubroutine(program)
+//        if(subroutine!=null) {
+//            val first = subroutine.statements.asSequence().filterNot { it is VarDecl || it is Directive }.firstOrNull()
+//            if(first is Return && first.value!=null) {
+//                val constval = first.value?.constValue(program)
+//                if(constval!=null)
+//                    return listOf(IAstModification.ReplaceNode(functionCall, constval, parent))
+//            }
+//        }
+//        return noModifications
+//    }
 
     override fun after(ifStatement: IfStatement, parent: Node): Iterable<IAstModification> {
         // remove empty if statements
-        if(ifStatement.truepart.containsNoCodeNorVars() && ifStatement.elsepart.containsNoCodeNorVars())
-            return listOf(IAstModification.Remove(ifStatement, ifStatement.definingScope()))
+        if(ifStatement.truepart.isEmpty() && ifStatement.elsepart.isEmpty())
+            return listOf(IAstModification.Remove(ifStatement, parent as IStatementContainer))
 
         // empty true part? switch with the else part
-        if(ifStatement.truepart.containsNoCodeNorVars() && ifStatement.elsepart.containsCodeOrVars()) {
+        if(ifStatement.truepart.isEmpty() && ifStatement.elsepart.isNotEmpty()) {
             val invertedCondition = PrefixExpression("not", ifStatement.condition, ifStatement.condition.position)
             val emptyscope = AnonymousScope(mutableListOf(), ifStatement.elsepart.position)
             val truepart = AnonymousScope(ifStatement.elsepart.statements, ifStatement.truepart.position)
@@ -181,20 +185,20 @@ internal class StatementOptimizer(private val program: Program,
     }
 
     override fun after(forLoop: ForLoop, parent: Node): Iterable<IAstModification> {
-        if(forLoop.body.containsNoCodeNorVars()) {
+        if(forLoop.body.isEmpty()) {
             errors.warn("removing empty for loop", forLoop.position)
-            return listOf(IAstModification.Remove(forLoop, forLoop.definingScope()))
+            return listOf(IAstModification.Remove(forLoop, parent as IStatementContainer))
         } else if(forLoop.body.statements.size==1) {
             val loopvar = forLoop.body.statements[0] as? VarDecl
             if(loopvar!=null && loopvar.name==forLoop.loopVar.nameInSource.singleOrNull()) {
                 // remove empty for loop (only loopvar decl in it)
-                return listOf(IAstModification.Remove(forLoop, forLoop.definingScope()))
+                return listOf(IAstModification.Remove(forLoop, parent as IStatementContainer))
             }
         }
 
         val range = forLoop.iterable as? RangeExpr
         if(range!=null) {
-            if(range.size()==1) {
+            if (range.size() == 1) {
                 // for loop over a (constant) range of just a single value-- optimize the loop away
                 // loopvar/reg = range value , follow by block
                 val scope = AnonymousScope(mutableListOf(), forLoop.position)
@@ -203,14 +207,14 @@ internal class StatementOptimizer(private val program: Program,
                 return listOf(IAstModification.ReplaceNode(forLoop, scope, parent))
             }
         }
-        val iterable = (forLoop.iterable as? IdentifierReference)?.targetVarDecl(program.namespace)
+        val iterable = (forLoop.iterable as? IdentifierReference)?.targetVarDecl(program)
         if(iterable!=null) {
             if(iterable.datatype==DataType.STR) {
                 val sv = iterable.value as StringLiteralValue
                 val size = sv.value.length
                 if(size==1) {
                     // loop over string of length 1 -> just assign the single character
-                    val character = CompilationTarget.instance.encodeString(sv.value, sv.altEncoding)[0]
+                    val character = compTarget.encodeString(sv.value, sv.altEncoding)[0]
                     val byte = NumericLiteralValue(DataType.UBYTE, character, iterable.position)
                     val scope = AnonymousScope(mutableListOf(), forLoop.position)
                     scope.statements.add(Assignment(AssignTarget(forLoop.loopVar, null, null, forLoop.position), byte, forLoop.position))
@@ -265,7 +269,7 @@ internal class StatementOptimizer(private val program: Program,
             } else {
                 // always false -> remove the while statement altogether
                 errors.warn("condition is always false", whileLoop.condition.position)
-                listOf(IAstModification.Remove(whileLoop, whileLoop.definingScope()))
+                listOf(IAstModification.Remove(whileLoop, parent as IStatementContainer))
             }
         }
         return noModifications
@@ -274,14 +278,14 @@ internal class StatementOptimizer(private val program: Program,
     override fun after(repeatLoop: RepeatLoop, parent: Node): Iterable<IAstModification> {
         val iter = repeatLoop.iterations
         if(iter!=null) {
-            if(repeatLoop.body.containsNoCodeNorVars()) {
+            if(repeatLoop.body.isEmpty()) {
                 errors.warn("empty loop removed", repeatLoop.position)
-                return listOf(IAstModification.Remove(repeatLoop, repeatLoop.definingScope()))
+                return listOf(IAstModification.Remove(repeatLoop, parent as IStatementContainer))
             }
             val iterations = iter.constValue(program)?.number?.toInt()
             if (iterations == 0) {
                 errors.warn("iterations is always 0, removed loop", iter.position)
-                return listOf(IAstModification.Remove(repeatLoop, repeatLoop.definingScope()))
+                return listOf(IAstModification.Remove(repeatLoop, parent as IStatementContainer))
             }
             if (iterations == 1) {
                 errors.warn("iterations is always 1", iter.position)
@@ -291,24 +295,12 @@ internal class StatementOptimizer(private val program: Program,
         return noModifications
     }
 
-    override fun after(whenStatement: WhenStatement, parent: Node): Iterable<IAstModification> {
-        // remove empty choices
-        class ChoiceRemover(val choice: WhenChoice) : IAstModification {
-            override fun perform() {
-                whenStatement.choices.remove(choice)
-            }
-        }
-        return whenStatement.choices
-                .filter { !it.statements.containsCodeOrVars() }
-                .map { ChoiceRemover(it) }
-    }
-
     override fun after(jump: Jump, parent: Node): Iterable<IAstModification> {
         // if the jump is to the next statement, remove the jump
-        val scope = jump.definingScope()
-        val label = jump.identifier?.targetStatement(scope)
+        val scope = jump.parent as IStatementContainer
+        val label = jump.identifier?.targetStatement(program)
         if(label!=null && scope.statements.indexOf(label) == scope.statements.indexOf(jump)+1)
-            return listOf(IAstModification.Remove(jump, jump.definingScope()))
+            return listOf(IAstModification.Remove(jump, scope))
 
         return noModifications
     }
@@ -341,7 +333,7 @@ internal class StatementOptimizer(private val program: Program,
                                 )
                                 return listOf(
                                         IAstModification.ReplaceNode(binExpr, expr2, binExpr.parent),
-                                        IAstModification.InsertAfter(assignment, addConstant, assignment.definingScope()))
+                                        IAstModification.InsertAfter(assignment, addConstant, parent as IStatementContainer))
                             } else if (op2 == "-") {
                                 // A = A +/- B - N
                                 val expr2 = BinaryExpression(binExpr.left, binExpr.operator, rExpr.left, binExpr.position)
@@ -352,7 +344,7 @@ internal class StatementOptimizer(private val program: Program,
                                 )
                                 return listOf(
                                         IAstModification.ReplaceNode(binExpr, expr2, binExpr.parent),
-                                        IAstModification.InsertAfter(assignment, subConstant, assignment.definingScope()))
+                                        IAstModification.InsertAfter(assignment, subConstant, parent as IStatementContainer))
                             }
                         }
                     }
@@ -374,7 +366,7 @@ internal class StatementOptimizer(private val program: Program,
     override fun after(assignment: Assignment, parent: Node): Iterable<IAstModification> {
         if(assignment.target isSameAs assignment.value) {
             // remove assignment to self
-            return listOf(IAstModification.Remove(assignment, assignment.definingScope()))
+            return listOf(IAstModification.Remove(assignment, parent as IStatementContainer))
         }
 
         val targetIDt = assignment.target.inferType(program)
@@ -382,7 +374,7 @@ internal class StatementOptimizer(private val program: Program,
             throw FatalAstException("can't infer type of assignment target")
 
         // optimize binary expressions a bit
-        val targetDt = targetIDt.typeOrElse(DataType.STRUCT)
+        val targetDt = targetIDt.getOr(DataType.UNDEFINED)
         val bexpr=assignment.value as? BinaryExpression
         if(bexpr!=null) {
             val rightCv = bexpr.right.constValue(program)?.number?.toDouble()
@@ -390,17 +382,17 @@ internal class StatementOptimizer(private val program: Program,
                 // assignments of the form:  X = X <operator> <expr>
                 // remove assignments that have no effect (such as X=X+0)
                 // optimize/rewrite some other expressions
-                val vardeclDt = (assignment.target.identifier?.targetVarDecl(program.namespace))?.type
+                val vardeclDt = (assignment.target.identifier?.targetVarDecl(program))?.type
                 when (bexpr.operator) {
                     "+" -> {
                         if (rightCv == 0.0) {
-                            return listOf(IAstModification.Remove(assignment, assignment.definingScope()))
+                            return listOf(IAstModification.Remove(assignment, parent as IStatementContainer))
                         } else if (targetDt in IntegerDatatypes && floor(rightCv) == rightCv) {
                             if (vardeclDt != VarDeclType.MEMORY && rightCv in 1.0..4.0) {
                                 // replace by several INCs if it's not a memory address (inc on a memory mapped register doesn't work very well)
                                 val incs = AnonymousScope(mutableListOf(), assignment.position)
                                 repeat(rightCv.toInt()) {
-                                    incs.statements.add(PostIncrDecr(assignment.target, "++", assignment.position))
+                                    incs.statements.add(PostIncrDecr(assignment.target.copy(), "++", assignment.position))
                                 }
                                 return listOf(IAstModification.ReplaceNode(assignment, incs, parent))
                             }
@@ -408,30 +400,30 @@ internal class StatementOptimizer(private val program: Program,
                     }
                     "-" -> {
                         if (rightCv == 0.0) {
-                            return listOf(IAstModification.Remove(assignment, assignment.definingScope()))
+                            return listOf(IAstModification.Remove(assignment, parent as IStatementContainer))
                         } else if (targetDt in IntegerDatatypes && floor(rightCv) == rightCv) {
                             if (vardeclDt != VarDeclType.MEMORY && rightCv in 1.0..4.0) {
                                 // replace by several DECs if it's not a memory address (dec on a memory mapped register doesn't work very well)
                                 val decs = AnonymousScope(mutableListOf(), assignment.position)
                                 repeat(rightCv.toInt()) {
-                                    decs.statements.add(PostIncrDecr(assignment.target, "--", assignment.position))
+                                    decs.statements.add(PostIncrDecr(assignment.target.copy(), "--", assignment.position))
                                 }
                                 return listOf(IAstModification.ReplaceNode(assignment, decs, parent))
                             }
                         }
                     }
-                    "*" -> if (rightCv == 1.0) return listOf(IAstModification.Remove(assignment, assignment.definingScope()))
-                    "/" -> if (rightCv == 1.0) return listOf(IAstModification.Remove(assignment, assignment.definingScope()))
-                    "**" -> if (rightCv == 1.0) return listOf(IAstModification.Remove(assignment, assignment.definingScope()))
-                    "|" -> if (rightCv == 0.0) return listOf(IAstModification.Remove(assignment, assignment.definingScope()))
-                    "^" -> if (rightCv == 0.0) return listOf(IAstModification.Remove(assignment, assignment.definingScope()))
+                    "*" -> if (rightCv == 1.0) return listOf(IAstModification.Remove(assignment, parent as IStatementContainer))
+                    "/" -> if (rightCv == 1.0) return listOf(IAstModification.Remove(assignment, parent as IStatementContainer))
+                    "**" -> if (rightCv == 1.0) return listOf(IAstModification.Remove(assignment, parent as IStatementContainer))
+                    "|" -> if (rightCv == 0.0) return listOf(IAstModification.Remove(assignment, parent as IStatementContainer))
+                    "^" -> if (rightCv == 0.0) return listOf(IAstModification.Remove(assignment, parent as IStatementContainer))
                     "<<" -> {
                         if (rightCv == 0.0)
-                            return listOf(IAstModification.Remove(assignment, assignment.definingScope()))
+                            return listOf(IAstModification.Remove(assignment, parent as IStatementContainer))
                     }
                     ">>" -> {
                         if (rightCv == 0.0)
-                            return listOf(IAstModification.Remove(assignment, assignment.definingScope()))
+                            return listOf(IAstModification.Remove(assignment, parent as IStatementContainer))
                     }
                 }
 
@@ -442,23 +434,19 @@ internal class StatementOptimizer(private val program: Program,
     }
 
     override fun after(returnStmt: Return, parent: Node): Iterable<IAstModification> {
-        fun returnViaIntermediary(value: Expression): Iterable<IAstModification>? {
-            val returnDt = returnStmt.definingSubroutine()!!.returntypes.single()
+        fun returnViaIntermediaryVar(value: Expression): Iterable<IAstModification>? {
+            val subr = returnStmt.definingSubroutine!!
+            val returnDt = subr.returntypes.single()
             if (returnDt in IntegerDatatypes) {
-                // first assign to intermediary, then return that register
-                val returnValueIntermediary =
-                    when(returnDt) {
-                        DataType.UBYTE -> IdentifierReference(listOf("prog8_lib", "retval_interm_ub"), returnStmt.position)
-                        DataType.BYTE -> IdentifierReference(listOf("prog8_lib", "retval_interm_b"), returnStmt.position)
-                        DataType.UWORD -> IdentifierReference(listOf("prog8_lib", "retval_interm_uw"), returnStmt.position)
-                        DataType.WORD -> IdentifierReference(listOf("prog8_lib", "retval_interm_w"), returnStmt.position)
-                        else -> throw FatalAstException("weird return dt")
-                    }
-                val tgt = AssignTarget(returnValueIntermediary, null, null, returnStmt.position)
+                // first assign to intermediary variable, then return that
+                subsThatNeedReturnVariable.add(Triple(subr, returnDt, returnStmt.position))
+                val returnValueIntermediary1 = IdentifierReference(listOf(retvarName), returnStmt.position)
+                val returnValueIntermediary2 = IdentifierReference(listOf(retvarName), returnStmt.position)
+                val tgt = AssignTarget(returnValueIntermediary1, null, null, returnStmt.position)
                 val assign = Assignment(tgt, value, returnStmt.position)
-                val returnReplacement = Return(returnValueIntermediary, returnStmt.position)
+                val returnReplacement = Return(returnValueIntermediary2, returnStmt.position)
                 return listOf(
-                    IAstModification.InsertBefore(returnStmt, assign, parent as INameScope),
+                    IAstModification.InsertBefore(returnStmt, assign, parent as IStatementContainer),
                     IAstModification.ReplaceNode(returnStmt, returnReplacement, parent)
                 )
             }
@@ -467,12 +455,12 @@ internal class StatementOptimizer(private val program: Program,
 
         when(returnStmt.value) {
             is PrefixExpression -> {
-                val mod = returnViaIntermediary(returnStmt.value!!)
+                val mod = returnViaIntermediaryVar(returnStmt.value!!)
                 if(mod!=null)
                     return mod
             }
             is BinaryExpression -> {
-                val mod = returnViaIntermediary(returnStmt.value!!)
+                val mod = returnViaIntermediaryVar(returnStmt.value!!)
                 if(mod!=null)
                     return mod
             }
@@ -482,7 +470,7 @@ internal class StatementOptimizer(private val program: Program,
         return super.after(returnStmt, parent)
     }
 
-    private fun hasBreak(scope: INameScope): Boolean {
+    private fun hasBreak(scope: IStatementContainer): Boolean {
 
         class Searcher: IAstVisitor
         {

codeOptimizers/src/prog8/optimizer/UnusedCodeRemover.kt

@@ -0,0 +1,144 @@
+package prog8.optimizer
+
+import prog8.ast.*
+import prog8.ast.base.VarDeclType
+import prog8.ast.expressions.BinaryExpression
+import prog8.ast.expressions.FunctionCall
+import prog8.ast.expressions.PrefixExpression
+import prog8.ast.expressions.TypecastExpression
+import prog8.ast.statements.*
+import prog8.ast.walk.AstWalker
+import prog8.ast.walk.IAstModification
+import prog8.compilerinterface.CallGraph
+import prog8.compilerinterface.ICompilationTarget
+import prog8.compilerinterface.IErrorReporter
+import prog8.compilerinterface.isInRegularRAMof
+
+
+class UnusedCodeRemover(private val program: Program,
+                        private val errors: IErrorReporter,
+                        private val compTarget: ICompilationTarget
+): AstWalker() {
+
+    private val callgraph = CallGraph(program)
+
+    override fun before(module: Module, parent: Node): Iterable<IAstModification> {
+        return if (!module.isLibrary && (module.containsNoCodeNorVars || callgraph.unused(module)))
+            listOf(IAstModification.Remove(module, parent as IStatementContainer))
+        else
+            noModifications
+    }
+
+    override fun before(breakStmt: Break, parent: Node): Iterable<IAstModification> {
+        reportUnreachable(breakStmt, parent as IStatementContainer)
+        return emptyList()
+    }
+
+    override fun before(jump: Jump, parent: Node): Iterable<IAstModification> {
+        reportUnreachable(jump, parent as IStatementContainer)
+        return emptyList()
+    }
+
+    override fun before(returnStmt: Return, parent: Node): Iterable<IAstModification> {
+        reportUnreachable(returnStmt, parent as IStatementContainer)
+        return emptyList()
+    }
+
+    override fun before(functionCallStatement: FunctionCallStatement, parent: Node): Iterable<IAstModification> {
+        if(functionCallStatement.target.nameInSource.last() == "exit")
+            reportUnreachable(functionCallStatement, parent as IStatementContainer)
+        return emptyList()
+    }
+
+    private fun reportUnreachable(stmt: Statement, parent: IStatementContainer) {
+        when(val next = stmt.nextSibling()) {
+            null, is Label, is Directive, is VarDecl, is InlineAssembly, is Subroutine -> {}
+            else -> errors.warn("unreachable code", next.position)
+        }
+    }
+
+    override fun after(scope: AnonymousScope, parent: Node): Iterable<IAstModification> {
+        val removeDoubleAssignments = deduplicateAssignments(scope.statements)
+        return removeDoubleAssignments.map { IAstModification.Remove(it, scope) }
+    }
+
+    override fun after(block: Block, parent: Node): Iterable<IAstModification> {
+        if("force_output" !in block.options()) {
+            if (block.containsNoCodeNorVars) {
+                if(block.name != internedStringsModuleName)
+                    errors.warn("removing unused block '${block.name}'", block.position)
+                return listOf(IAstModification.Remove(block, parent as IStatementContainer))
+            }
+            if(callgraph.unused(block)) {
+                errors.warn("removing unused block '${block.name}'", block.position)
+                return listOf(IAstModification.Remove(block, parent as IStatementContainer))
+            }
+        }
+
+        val removeDoubleAssignments = deduplicateAssignments(block.statements)
+        return removeDoubleAssignments.map { IAstModification.Remove(it, block) }
+    }
+
+    override fun after(subroutine: Subroutine, parent: Node): Iterable<IAstModification> {
+        val forceOutput = "force_output" in subroutine.definingBlock.options()
+        if (subroutine !== program.entrypoint && !forceOutput && !subroutine.inline && !subroutine.isAsmSubroutine) {
+            if(callgraph.unused(subroutine)) {
+                if(subroutine.containsNoCodeNorVars) {
+                    if(!subroutine.definingModule.isLibrary)
+                        errors.warn("removing empty subroutine '${subroutine.name}'", subroutine.position)
+                    val removals = mutableListOf(IAstModification.Remove(subroutine, parent as IStatementContainer))
+                    callgraph.calledBy[subroutine]?.let {
+                        for(node in it)
+                            removals.add(IAstModification.Remove(node, node.parent as IStatementContainer))
+                    }
+                    return removals
+                }
+                if(!subroutine.definingModule.isLibrary)
+                    errors.warn("removing unused subroutine '${subroutine.name}'", subroutine.position)
+                return listOf(IAstModification.Remove(subroutine, parent as IStatementContainer))
+            }
+        }
+
+        val removeDoubleAssignments = deduplicateAssignments(subroutine.statements)
+        return removeDoubleAssignments.map { IAstModification.Remove(it, subroutine) }
+    }
+
+    override fun after(decl: VarDecl, parent: Node): Iterable<IAstModification> {
+        if(decl.type==VarDeclType.VAR) {
+            val forceOutput = "force_output" in decl.definingBlock.options()
+            if (!forceOutput && !decl.autogeneratedDontRemove && !decl.sharedWithAsm && !decl.definingBlock.isInLibrary) {
+                if (callgraph.unused(decl)) {
+                    errors.warn("removing unused variable '${decl.name}'", decl.position)
+                    return listOf(IAstModification.Remove(decl, parent as IStatementContainer))
+                }
+            }
+        }
+
+        return noModifications
+    }
+
+    private fun deduplicateAssignments(statements: List<Statement>): List<Assignment> {
+        // removes 'duplicate' assignments that assign the same target directly after another
+        val linesToRemove = mutableListOf<Assignment>()
+
+        for (stmtPairs in statements.windowed(2, step = 1)) {
+            val assign1 = stmtPairs[0] as? Assignment
+            val assign2 = stmtPairs[1] as? Assignment
+            if (assign1 != null && assign2 != null && !assign2.isAugmentable) {
+                if (assign1.target.isSameAs(assign2.target, program) && assign1.target.isInRegularRAMof(compTarget.machine))  {
+                    if(assign2.target.identifier==null || !assign2.value.referencesIdentifier(*(assign2.target.identifier!!.nameInSource.toTypedArray())))
+                        // only remove the second assignment if its value is a simple expression!
+                        when(assign2.value) {
+                            is PrefixExpression,
+                            is BinaryExpression,
+                            is TypecastExpression,
+                            is FunctionCall -> { /* don't remove */ }
+                            else -> linesToRemove.add(assign1)
+                        }
+                }
+            }
+        }
+
+        return linesToRemove
+    }
+}

codeOptimizers/test/readme.txt

@@ -0,0 +1,2 @@
+Unittests for things in this module are located in the Compiler module instead,
+for convenience sake - and to not spread the test cases around too much.

compiler/build.gradle

@@ -1,51 +1,47 @@
 plugins {
     id 'java'
     id 'application'
-    id "org.jetbrains.kotlin.jvm" version "1.4.21"
-    id 'org.jetbrains.dokka' version "0.9.18"
-    id 'com.github.johnrengelman.shadow' version '6.1.0'
+    id "org.jetbrains.kotlin.jvm"
+    id 'com.github.johnrengelman.shadow' version '7.1.0'
 }
 
-targetCompatibility = 11
-sourceCompatibility = 11
-
-repositories {
-    mavenLocal()
-    mavenCentral()
-    maven { url "https://kotlin.bintray.com/kotlinx" }
+java {
+    toolchain {
+        languageVersion = JavaLanguageVersion.of(javaVersion)
+    }
 }
 
 def prog8version = rootProject.file('compiler/res/version.txt').text.trim()
 
 dependencies {
-    implementation project(':parser')
+    implementation project(':compilerInterfaces')
+    implementation project(':codeOptimizers')
+    implementation project(':compilerAst')
+    implementation project(':codeGeneration')
     implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8"
     // implementation "org.jetbrains.kotlin:kotlin-reflect"
-    implementation 'org.antlr:antlr4-runtime:4.8'
-    implementation 'org.jetbrains.kotlinx:kotlinx-cli:0.3.1'
-    // implementation 'net.razorvine:ksim65:1.8'
-    // implementation "com.github.hypfvieh:dbus-java:3.2.4"
-    implementation project(':parser')
+    implementation 'org.jetbrains.kotlinx:kotlinx-cli:0.3.3'
+    implementation "com.michael-bull.kotlin-result:kotlin-result-jvm:1.1.12"
 
     testImplementation "org.jetbrains.kotlin:kotlin-test-junit5"
-    testImplementation 'org.junit.jupiter:junit-jupiter-api:5.3.2'
-    testImplementation 'org.hamcrest:hamcrest-junit:2.0.0.0'
-    testRuntimeOnly 'org.junit.jupiter:junit-jupiter-engine:5.3.2'
+    testImplementation 'org.junit.jupiter:junit-jupiter-api:5.7.2'
+    testImplementation 'org.hamcrest:hamcrest:2.2'
+    testRuntimeOnly 'org.junit.jupiter:junit-jupiter-engine:5.7.2'
 }
 
-compileKotlin {
-    kotlinOptions {
-        jvmTarget = "11"
-        // verbose = true
-        // freeCompilerArgs += "-XXLanguage:+NewInference"
+configurations.all {
+    exclude group: 'com.ibm.icu', module: 'icu4j'
+    exclude group: "org.antlr", module: "antlr4"
+}
+
+configurations {
+    // strange antlr plugin issue, see https://github.com/gradle/gradle/issues/820
+    // this avoids linking in the complete antlr binary jar
+    compile {
+        extendsFrom = extendsFrom.findAll { it != configurations.antlr }
     }
 }
 
-compileTestKotlin {
-    kotlinOptions {
-        jvmTarget = "11"
-    }
-}
 
 sourceSets {
     main {
@@ -58,7 +54,8 @@ sourceSets {
     }
     test {
         java {
-            srcDirs = ["${project.projectDir}/test"]
+            srcDir "${project.projectDir}/test"
+            srcDir "${project(':compilerAst').projectDir}/test/helpers"
         }
     }
 }
@@ -67,15 +64,9 @@ startScripts.enabled = true
 
 application {
     mainClass = 'prog8.CompilerMainKt'
-    mainClassName = 'prog8.CompilerMainKt'  // deprecated
     applicationName = 'p8compile'
 }
 
-artifacts {
-    archives shadowJar
-}
-
-
 shadowJar {
     archiveBaseName = 'prog8compiler'
     archiveVersion = prog8version
@@ -96,12 +87,4 @@ test {
     }
 }
 
-
-dokka {
-    outputFormat = 'html'
-    outputDirectory = "$buildDir/kdoc"
-}
-
-task wrapper(type: Wrapper) {
-    gradleVersion = '6.7'
-}
+build.finalizedBy installDist, installShadowDist

compiler/compiler.iml

@@ -1,5 +1,10 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <module type="JAVA_MODULE" version="4">
+  <component name="FacetManager">
+    <facet type="Python" name="Python">
+      <configuration sdkName="Python 3.9" />
+    </facet>
+  </component>
   <component name="NewModuleRootManager" inherit-compiler-output="true">
     <exclude-output />
     <content url="file://$MODULE_DIR$">
@@ -8,12 +13,17 @@
       <sourceFolder url="file://$MODULE_DIR$/test" isTestSource="true" />
       <excludeFolder url="file://$MODULE_DIR$/build" />
     </content>
-    <orderEntry type="jdk" jdkName="11" jdkType="JavaSDK" />
+    <orderEntry type="jdk" jdkName="openjdk-11" jdkType="JavaSDK" />
     <orderEntry type="sourceFolder" forTests="false" />
     <orderEntry type="library" name="KotlinJavaRuntime" level="project" />
-    <orderEntry type="module" module-name="parser" />
-    <orderEntry type="library" name="unittest-libs" level="project" />
-    <orderEntry type="library" name="kotlinx-cli-jvm" level="project" />
-    <orderEntry type="library" name="antlr-runtime-4.9" level="project" />
+    <orderEntry type="module" module-name="compilerAst" />
+    <orderEntry type="library" name="Python 3.9 interpreter library" level="application" />
+    <orderEntry type="library" name="hamcrest" level="project" />
+    <orderEntry type="library" name="jetbrains.kotlinx.cli.jvm" level="project" />
+    <orderEntry type="library" name="junit.jupiter" level="project" />
+    <orderEntry type="library" name="michael.bull.kotlin.result.jvm" level="project" />
+    <orderEntry type="module" module-name="codeOptimizers" />
+    <orderEntry type="module" module-name="compilerInterfaces" />
+    <orderEntry type="module" module-name="codeGeneration" />
   </component>
 </module>

compiler/res/prog8lib/c64/floats.asm

@@ -428,7 +428,9 @@ var_fac1_greater_f	.proc
 		cmp  #1
 		beq  +
 		lda  #0
-+		rts
+		rts
++		lda  #1
+		rts
 		.pend
 
 var_fac1_greatereq_f	.proc

compiler/res/prog8lib/c64/floats.p8

@@ -4,7 +4,6 @@
 ;
 ; indent format: TABS, size=8
 
-%target c64
 %option enable_floats
 
 floats {
@@ -13,6 +12,7 @@ floats {
         const float  PI     = 3.141592653589793
         const float  TWOPI  = 6.283185307179586
 
+        ubyte[5] tempvar_swap_float     ; used for some swap() operations
 
 ; ---- C64 basic and kernal ROM float constants and functions ----
 
@@ -83,7 +83,7 @@ romsub $bc58 = ABS()                                        ; fac1 = ABS(fac1)
 romsub $bf71 = SQR() clobbers(A,X,Y)                        ; fac1 = SQRT(fac1)
 romsub $bf74 = SQRA() clobbers(A,X,Y)                       ; fac1 = SQRT(fac2)
 romsub $bfed = EXP() clobbers(A,X,Y)                        ; fac1 = EXP(fac1)  (e ** fac1)
-romsub $bfb4 = NEGOP() clobbers(A)                          ; switch the sign of fac1
+romsub $bfb4 = NEGOP() clobbers(A)                          ; switch the sign of fac1 (fac1 = -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)
@@ -195,7 +195,7 @@ sub  print_f  (float value) {
 	}}
 }
 
-%asminclude "library:c64/floats.asm", ""
-%asminclude "library:c64/floats_funcs.asm", ""
+%asminclude "library:c64/floats.asm"
+%asminclude "library:c64/floats_funcs.asm"
 
 }

compiler/res/prog8lib/c64/graphics.p8

@@ -1,8 +1,7 @@
-%target c64
 %import textio
 
 ; bitmap pixel graphics module for the C64
-; only black/white monchrome 320x200 for now
+; only black/white monochrome 320x200 for now
 ; assumes bitmap screen memory is $2000-$3fff
 
 graphics {
@@ -39,30 +38,28 @@ graphics {
             swap(x1, x2)
             swap(y1, y2)
         }
-        word @zp dx = x2-x1 as word
-        word @zp dy = y2-y1
+        word @zp dx = (x2 as word)-x1
+        word @zp dy = (y2 as word)-y1
 
         if dx==0 {
-            vertical_line(x1, y1, abs(dy)+1 as ubyte)
+            vertical_line(x1, y1, abs(dy) as ubyte +1)
             return
         }
         if dy==0 {
             if x1>x2
                 x1=x2
-            horizontal_line(x1, y1, abs(dx)+1 as uword)
+            horizontal_line(x1, y1, abs(dx) as uword +1)
             return
         }
 
-        ; TODO rewrite the rest in optimized assembly
-
         word @zp d = 0
         ubyte positive_ix = true
         if dx < 0 {
             dx = -dx
             positive_ix = false
         }
-        dx *= 2
-        dy *= 2
+        word @zp dx2 = dx*2
+        word @zp dy2 = dy*2
         internal_plotx = x1
 
         if dx >= dy {
@@ -72,10 +69,10 @@ graphics {
                     if internal_plotx==x2
                         return
                     internal_plotx++
-                    d += dy
+                    d += dy2
                     if d > dx {
                         y1++
-                        d -= dx
+                        d -= dx2
                     }
                 }
             } else {
@@ -84,10 +81,10 @@ graphics {
                     if internal_plotx==x2
                         return
                     internal_plotx--
-                    d += dy
+                    d += dy2
                     if d > dx {
                         y1++
-                        d -= dx
+                        d -= dx2
                     }
                 }
             }
@@ -99,10 +96,10 @@ graphics {
                     if y1 == y2
                         return
                     y1++
-                    d += dx
+                    d += dx2
                     if d > dy {
                         internal_plotx++
-                        d -= dy
+                        d -= dy2
                     }
                 }
             } else {
@@ -111,10 +108,10 @@ graphics {
                     if y1 == y2
                         return
                     y1++
-                    d += dx
+                    d += dx2
                     if d > dy {
                         internal_plotx--
-                        d -= dy
+                        d -= dy2
                     }
                 }
             }

compiler/res/prog8lib/c64/syslib.p8

@@ -5,13 +5,11 @@
 ;
 ; indent format: TABS, size=8
 
-%target c64
-
 c64 {
         &ubyte  TIME_HI         = $a0       ; software jiffy clock, hi byte
         &ubyte  TIME_MID        = $a1       ;  .. mid byte
         &ubyte  TIME_LO         = $a2       ;    .. lo byte. Updated by IRQ every 1/60 sec
-        &ubyte  STATUS          = $90       ; kernel status variable for I/O
+        &ubyte  STATUS          = $90       ; kernal status variable for I/O
         &ubyte  STKEY           = $91       ; various keyboard statuses (updated by IRQ)
         &ubyte  SFDX            = $cb       ; current key pressed (matrix value) (updated by IRQ)
 
@@ -178,7 +176,7 @@ c64 {
 
 ; ---- C64 ROM kernal routines ----
 
-romsub $AB1E = STROUT(uword strptr @ AY) clobbers(A, X, Y)      ; print null-terminated string (use c64scr.print instead)
+romsub $AB1E = STROUT(uword strptr @ AY) clobbers(A, X, Y)      ; print null-terminated string (use txt.print instead)
 romsub $E544 = CLEARSCR() clobbers(A,X,Y)                       ; clear the screen
 romsub $E566 = HOMECRSR() clobbers(A,X,Y)                       ; cursor to top left of screen
 romsub $EA31 = IRQDFRT() clobbers(A,X,Y)                        ; default IRQ routine
@@ -202,7 +200,7 @@ romsub $FFAE = UNLSN() clobbers(A)                              ; command serial
 romsub $FFB1 = LISTEN(ubyte device @ A) clobbers(A)             ; command serial bus device to LISTEN
 romsub $FFB4 = TALK(ubyte device @ A) clobbers(A)               ; command serial bus device to TALK
 romsub $FFB7 = READST() -> ubyte @ A                            ; read I/O status word
-romsub $FFBA = SETLFS(ubyte logical @ A, ubyte device @ X, ubyte address @ Y)   ; set logical file parameters
+romsub $FFBA = SETLFS(ubyte logical @ A, ubyte device @ X, ubyte secondary @ Y)   ; set logical file parameters
 romsub $FFBD = SETNAM(ubyte namelen @ A, str filename @ XY)     ; set filename parameters
 romsub $FFC0 = OPEN() clobbers(X,Y) -> ubyte @Pc, ubyte @A      ; (via 794 ($31A)) open a logical file
 romsub $FFC3 = CLOSE(ubyte logical @ A) clobbers(A,X,Y)         ; (via 796 ($31C)) close a logical file
@@ -211,10 +209,10 @@ romsub $FFC9 = CHKOUT(ubyte logical @ X) clobbers(A,X)          ; (via 800 ($320
 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 $FFD5 = LOAD(ubyte verify @ A, uword address @ XY) -> ubyte @Pc, ubyte @ A, ubyte @ X, ubyte @ Y     ; (via 816 ($330)) load from device
-romsub $FFD8 = SAVE(ubyte zp_startaddr @ A, uword endaddr @ XY) -> ubyte @ Pc, ubyte @ A                    ; (via 818 ($332)) save to a device
+romsub $FFD5 = LOAD(ubyte verify @ A, uword address @ XY) -> ubyte @Pc, ubyte @ A, uword @ XY     ; (via 816 ($330)) load from device
+romsub $FFD8 = SAVE(ubyte zp_startaddr @ A, uword endaddr @ XY) -> ubyte @ Pc, ubyte @ A          ; (via 818 ($332)) save to a device
 romsub $FFDB = SETTIM(ubyte low @ A, ubyte middle @ X, ubyte high @ Y)      ; set the software clock
-romsub $FFDE = RDTIM() -> ubyte @ A, ubyte @ X, ubyte @ Y       ; read the software clock
+romsub $FFDE = RDTIM() -> ubyte @ A, ubyte @ X, ubyte @ Y       ; read the software clock (A=lo,X=mid,Y=high)
 romsub $FFE1 = STOP() clobbers(X) -> ubyte @ Pz, ubyte @ A      ; (via 808 ($328)) check the STOP key (and some others in A)
 romsub $FFE4 = GETIN() clobbers(X,Y) -> ubyte @Pc, ubyte @ A    ; (via 810 ($32A)) get a character
 romsub $FFE7 = CLALL() clobbers(A,X)                            ; (via 812 ($32C)) close all files
@@ -246,7 +244,7 @@ asmsub STOP2() -> ubyte @A  {
 }
 
 asmsub RDTIM16() -> uword @AY {
-    ; --  like RDTIM() but only returning the lower 16 bits for convenience
+    ; --  like RDTIM() but only returning the lower 16 bits in AY for convenience
     %asm {{
         stx  P8ZP_SCRATCH_REG
         jsr  c64.RDTIM
@@ -294,6 +292,12 @@ asmsub  init_system()  {
     }}
 }
 
+asmsub  init_system_phase2()  {
+    %asm {{
+        rts     ; no phase 2 steps on the C64
+    }}
+}
+
 asmsub  disable_runstop_and_charsetswitch() clobbers(A) {
     %asm {{
         lda  #$80
@@ -304,27 +308,13 @@ asmsub  disable_runstop_and_charsetswitch() clobbers(A) {
     }}
 }
 
-asmsub  set_irqvec_excl() clobbers(A)  {
-	%asm {{
-		sei
-		lda  #<_irq_handler
-		sta  c64.CINV
-		lda  #>_irq_handler
-		sta  c64.CINV+1
-		cli
-		rts
-_irq_handler	jsr  set_irqvec._irq_handler_init
-		jsr  irq.irq
-		jsr  set_irqvec._irq_handler_end
-		lda  #$ff
-		sta  c64.VICIRQ			; acknowledge raster irq
-		lda  c64.CIA1ICR		; acknowledge CIA1 interrupt
-		jmp  c64.IRQDFEND		; end irq processing - don't call kernel
-	}}
-}
-
-asmsub  set_irqvec() clobbers(A)  {
+asmsub  set_irq(uword handler @AY, ubyte useKernal @Pc) clobbers(A)  {
 	%asm {{
+	        sta  _modified+1
+	        sty  _modified+2
+	        lda  #0
+	        adc  #0
+	        sta  _use_kernal
 		sei
 		lda  #<_irq_handler
 		sta  c64.CINV
@@ -333,9 +323,23 @@ asmsub  set_irqvec() clobbers(A)  {
 		cli
 		rts
 _irq_handler    jsr  _irq_handler_init
-		jsr  irq.irq
+_modified	jsr  $ffff                      ; modified
 		jsr  _irq_handler_end
-		jmp  c64.IRQDFRT		; continue with normal kernel irq routine
+		lda  _use_kernal
+		bne  +
+		lda  #$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  c64.IRQDFRT		; continue with normal kernal irq routine
+
+_use_kernal     .byte  0
 
 _irq_handler_init
 		; save all zp scratch registers and the X register as these might be clobbered by the irq routine
@@ -388,7 +392,7 @@ IRQ_SCRATCH_ZPWORD2	.word  0
 		}}
 }
 
-asmsub  restore_irqvec() clobbers(A) {
+asmsub  restore_irq() clobbers(A) {
 	%asm {{
 		sei
 		lda  #<c64.IRQDFRT
@@ -404,8 +408,15 @@ asmsub  restore_irqvec() clobbers(A) {
 	}}
 }
 
-asmsub  set_rasterirq(uword rasterpos @ AY) clobbers(A) {
+asmsub  set_rasterirq(uword handler @AY, uword rasterpos @R0, ubyte useKernal @Pc) clobbers(A) {
 	%asm {{
+	        sta  _modified+1
+	        sty  _modified+2
+	        lda  #0
+	        adc  #0
+	        sta  set_irq._use_kernal
+		lda  cx16.r0
+		ldy  cx16.r0+1
 		sei
 		jsr  _setup_raster_irq
 		lda  #<_raster_irq_handler
@@ -416,12 +427,21 @@ asmsub  set_rasterirq(uword rasterpos @ AY) clobbers(A) {
 		rts
 
 _raster_irq_handler
-		jsr  set_irqvec._irq_handler_init
-		jsr  irq.irq
-		jsr  set_irqvec._irq_handler_end
-		lda  #$ff
-		sta  c64.VICIRQ			; acknowledge raster irq
-		jmp  c64.IRQDFRT
+		jsr  set_irq._irq_handler_init
+_modified	jsr  $ffff              ; modified
+		jsr  set_irq._irq_handler_end
+                lda  #$ff
+                sta  c64.VICIRQ			; acknowledge raster irq
+		lda  set_irq._use_kernal
+		bne  +
+		; end irq processing - don't use kernal's irq handling
+		pla
+		tay
+		pla
+		tax
+		pla
+		rti
++		jmp  c64.IRQDFRT                ; continue with kernal irq routine
 
 _setup_raster_irq
 		pha
@@ -445,28 +465,6 @@ _setup_raster_irq
 	}}
 }
 
-asmsub  set_rasterirq_excl(uword rasterpos @ AY) clobbers(A) {
-	%asm {{
-		sei
-		jsr  set_rasterirq._setup_raster_irq
-		lda  #<_raster_irq_handler
-		sta  c64.CINV
-		lda  #>_raster_irq_handler
-		sta  c64.CINV+1
-		cli
-		rts
-
-_raster_irq_handler
-		jsr  set_irqvec._irq_handler_init
-		jsr  irq.irq
-		jsr  set_irqvec._irq_handler_end
-		lda  #$ff
-		sta  c64.VICIRQ			; acknowledge raster irq
-		jmp  c64.IRQDFEND		; end irq processing - don't call kernel
-
-	}}
-}
-
 ; ---- end of C64 specific system utility routines ----
 
 }
@@ -478,7 +476,7 @@ sys {
 
 
     asmsub  reset_system()  {
-        ; Soft-reset the system back to Basic prompt.
+        ; Soft-reset the system back to initial power-on Basic prompt.
         %asm {{
             sei
             lda  #14
@@ -489,6 +487,7 @@ sys {
 
     sub wait(uword jiffies) {
         ; --- wait approximately the given number of jiffies (1/60th seconds)
+        ;     note: the system irq handler has to be active for this to work as it depends on the system jiffy clock
         repeat jiffies {
             ubyte jiff = lsb(c64.RDTIM16())
             while jiff==lsb(c64.RDTIM16()) {
@@ -497,22 +496,47 @@ sys {
         }
     }
 
+    asmsub waitvsync() clobbers(A) {
+        ; --- busy wait till the next vsync has occurred (approximately), without depending on custom irq handling.
+        ;     note: a more accurate way to wait for vsync is to set up a vsync irq handler instead.
+        %asm {{
+-           bit  c64.SCROLY
+            bpl  -
+-           bit  c64.SCROLY
+            bmi  -
+            rts
+        }}
+    }
+
+    inline asmsub waitrastborder() {
+        ; --- busy wait till the raster position has reached the bottom screen border (approximately)
+        ;     note: a more accurate way to do this is by using a raster irq handler instead.
+        %asm {{
+-           bit  c64.SCROLY
+            bpl  -
+        }}
+    }
+
     asmsub memcopy(uword source @R0, uword target @R1, uword count @AY) clobbers(A,X,Y) {
         %asm {{
             ldx  cx16.r0
-            stx  P8ZP_SCRATCH_W1
+            stx  P8ZP_SCRATCH_W1        ; source in ZP
             ldx  cx16.r0+1
             stx  P8ZP_SCRATCH_W1+1
             ldx  cx16.r1
-            stx  P8ZP_SCRATCH_W2
+            stx  P8ZP_SCRATCH_W2        ; target in ZP
             ldx  cx16.r1+1
             stx  P8ZP_SCRATCH_W2+1
             cpy  #0
             bne  _longcopy
-            ; copy <= 255
-            tay
 
-_remainder
+            ; copy <= 255 bytes
+            tay
+            bne  _copyshort
+            rts     ; nothing to copy
+
+_copyshort
+            ; decrease source and target pointers so we can simply index by Y
             lda  P8ZP_SCRATCH_W1
             bne  +
             dec  P8ZP_SCRATCH_W1+1
@@ -521,18 +545,19 @@ _remainder
             bne  +
             dec  P8ZP_SCRATCH_W2+1
 +           dec  P8ZP_SCRATCH_W2
--           lda  (P8ZP_SCRATCH_W1), y
-            sta  (P8ZP_SCRATCH_W2), y
+
+-           lda  (P8ZP_SCRATCH_W1),y
+            sta  (P8ZP_SCRATCH_W2),y
             dey
             bne  -
             rts
 
 _longcopy
-            sta  P8ZP_SCRATCH_B1        ; lsb(count) = remainder
+            sta  P8ZP_SCRATCH_B1        ; lsb(count) = remainder in last page
             tya
             tax                         ; x = num pages (1+)
             ldy  #0
--           lda  (P8ZP_SCRATCH_W1),y    ; copy a page at a time
+-           lda  (P8ZP_SCRATCH_W1),y
             sta  (P8ZP_SCRATCH_W2),y
             iny
             bne  -
@@ -541,7 +566,8 @@ _longcopy
             dex
             bne  -
             ldy  P8ZP_SCRATCH_B1
-            jmp  _remainder
+            bne  _copyshort
+            rts
         }}
     }
 
@@ -673,4 +699,37 @@ cx16 {
     &uword r14 = $cf1c
     &uword r15 = $cf1e
 
+    &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 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
 }

compiler/res/prog8lib/c64/textio.p8

@@ -4,7 +4,6 @@
 ;
 ; indent format: TABS, size=8
 
-%target c64
 %import syslib
 %import conv
 
@@ -19,12 +18,27 @@ sub  clear_screen() {
     txt.chrout(147)
 }
 
+sub home() {
+    txt.chrout(19)
+}
+
 sub nl() {
     txt.chrout('\n')
 }
 
-sub home() {
-    txt.chrout(19)
+sub spc() {
+    txt.chrout(' ')
+}
+
+asmsub column(ubyte col @A) clobbers(A, X, Y) {
+    ; ---- set the cursor on the given column (starting with 0) on the current line
+    %asm {{
+        sec
+        jsr  c64.PLOT
+        tay
+        clc
+        jmp  c64.PLOT
+    }}
 }
 
 asmsub  fill_screen (ubyte char @ A, ubyte color @ Y) clobbers(A)  {
@@ -571,7 +585,7 @@ _colormod	sta  $ffff		; modified
 }
 
 asmsub  plot  (ubyte col @ Y, ubyte row @ A) clobbers(A) {
-	; ---- safe wrapper around PLOT kernel routine, to save the X register.
+	; ---- safe wrapper around PLOT kernal routine, to save the X register.
 	%asm  {{
 		stx  P8ZP_SCRATCH_REG
 		tax

compiler/res/prog8lib/conv.p8

@@ -7,239 +7,213 @@ conv {
 
 ; ----- number conversions to decimal strings ----
 
-asmsub  ubyte2decimal  (ubyte value @A) -> ubyte @Y, ubyte @A, ubyte @X  {
-	; ---- A to decimal string in Y/A/X  (100s in Y, 10s in A, 1s in X)
+    str  string_out = "????????????????"       ; result buffer for the string conversion routines
+
+asmsub  str_ub0  (ubyte value @ A) clobbers(A,Y)  {
+	; ---- convert the ubyte in A in decimal string form, with left padding 0s (3 positions total)
 	%asm {{
-		ldy  #uword2decimal.ASCII_0_OFFSET
-		bne  uword2decimal.hex_try200
-		rts
+            phx
+            jsr  conv.ubyte2decimal
+            sty  string_out
+            sta  string_out+1
+            stx  string_out+2
+            lda  #0
+            sta  string_out+3
+            plx
+            rts
 	}}
 }
 
-asmsub  uword2decimal  (uword value @AY) -> ubyte @Y, ubyte @A, ubyte @X  {
-	;  ---- convert 16 bit uword in A/Y to decimal
-	;  output in uword2decimal.decTenThousands, decThousands, decHundreds, decTens, decOnes
-	;  (these are terminated by a zero byte so they can be easily printed)
-	;  also returns Y = 100's, A = 10's, X = 1's
-
+asmsub  str_ub  (ubyte value @ A) clobbers(A,Y)  {
+	; ---- convert the ubyte in A in decimal string form, without left padding 0s
 	%asm {{
-
-;Convert 16 bit Hex to Decimal (0-65535) Rev 2
-;By Omegamatrix    Further optimizations by tepples
-; routine from http://forums.nesdev.com/viewtopic.php?f=2&t=11341&start=15
-
-;HexToDec99
-; start in A
-; end with A = 10's, decOnes (also in X)
-
-;HexToDec255
-; start in A
-; end with Y = 100's, A = 10's, decOnes (also in X)
-
-;HexToDec999
-; start with A = high byte, Y = low byte
-; end with Y = 100's, A = 10's, decOnes (also in X)
-; requires 1 extra temp register on top of decOnes, could combine
-; these two if HexToDec65535 was eliminated...
-
-;HexToDec65535
-; start with A/Y (low/high) as 16 bit value
-; end with decTenThousand, decThousand, Y = 100's, A = 10's, decOnes (also in X)
-; (irmen: I store Y and A in decHundreds and decTens too, so all of it can be easily printed)
-
-
-ASCII_0_OFFSET 	= $30
-temp       	    = P8ZP_SCRATCH_B1	; byte in zeropage
-hexHigh      	= P8ZP_SCRATCH_W1	; byte in zeropage
-hexLow       	= P8ZP_SCRATCH_W1+1	; byte in zeropage
-
-
-HexToDec65535; SUBROUTINE
-    sty    hexHigh               ;3  @9
-    sta    hexLow                ;3  @12
-    tya
-    tax                          ;2  @14
-    lsr    a                     ;2  @16
-    lsr    a                     ;2  @18   integer divide 1024 (result 0-63)
-
-    cpx    #$A7                  ;2  @20   account for overflow of multiplying 24 from 43,000 ($A7F8) onward,
-    adc    #1                    ;2  @22   we can just round it to $A700, and the divide by 1024 is fine...
-
-    ;at this point we have a number 1-65 that we have to times by 24,
-    ;add to original sum, and Mod 1024 to get a remainder 0-999
-
-
-    sta    temp                  ;3  @25
-    asl    a                     ;2  @27
-    adc    temp                  ;3  @30  x3
-    tay                          ;2  @32
-    lsr    a                     ;2  @34
-    lsr    a                     ;2  @36
-    lsr    a                     ;2  @38
-    lsr    a                     ;2  @40
-    lsr    a                     ;2  @42
-    tax                          ;2  @44
-    tya                          ;2  @46
-    asl    a                     ;2  @48
-    asl    a                     ;2  @50
-    asl    a                     ;2  @52
-    clc                          ;2  @54
-    adc    hexLow                ;3  @57
-    sta    hexLow                ;3  @60
-    txa                          ;2  @62
-    adc    hexHigh               ;3  @65
-    sta    hexHigh               ;3  @68
-    ror    a                     ;2  @70
-    lsr    a                     ;2  @72
-    tay                          ;2  @74    integer divide 1,000 (result 0-65)
-
-    lsr    a                     ;2  @76    split the 1,000 and 10,000 digit
-    tax                          ;2  @78
-    lda    ShiftedBcdTab,x       ;4  @82
-    tax                          ;2  @84
-    rol    a                     ;2  @86
-    and    #$0F                  ;2  @88
-    ora    #ASCII_0_OFFSET
-    sta    decThousands          ;3  @91
-    txa                          ;2  @93
-    lsr    a                     ;2  @95
-    lsr    a                     ;2  @97
-    lsr    a                     ;2  @99
-    ora    #ASCII_0_OFFSET
-    sta    decTenThousands       ;3  @102
-
-    lda    hexLow                ;3  @105
-    cpy    temp                  ;3  @108
-    bmi    _doSubtract           ;2³ @110/111
-    beq    _useZero               ;2³ @112/113
-    adc    #23 + 24              ;2  @114
-_doSubtract
-    sbc    #23                   ;2  @116
-    sta    hexLow                ;3  @119
-_useZero
-    lda    hexHigh               ;3  @122
-    sbc    #0                    ;2  @124
-
-Start100s
-    and    #$03                  ;2  @126
-    tax                          ;2  @128   0,1,2,3
-    cmp    #2                    ;2  @130
-    rol    a                     ;2  @132   0,2,5,7
-    ora    #ASCII_0_OFFSET
-    tay                          ;2  @134   Y = Hundreds digit
-
-    lda    hexLow                ;3  @137
-    adc    Mod100Tab,x           ;4  @141    adding remainder of 256, 512, and 256+512 (all mod 100)
-    bcs    hex_doSub200             ;2³ @143/144
-
-hex_try200
-    cmp    #200                  ;2  @145
-    bcc    hex_try100               ;2³ @147/148
-hex_doSub200
-    iny                          ;2  @149
-    iny                          ;2  @151
-    sbc    #200                  ;2  @153
-hex_try100
-    cmp    #100                  ;2  @155
-    bcc    HexToDec99            ;2³ @157/158
-    iny                          ;2  @159
-    sbc    #100                  ;2  @161
-
-HexToDec99; SUBROUTINE
-    lsr    a                     ;2  @163
-    tax                          ;2  @165
-    lda    ShiftedBcdTab,x       ;4  @169
-    tax                          ;2  @171
-    rol    a                     ;2  @173
-    and    #$0F                  ;2  @175
-    ora    #ASCII_0_OFFSET
-    sta    decOnes               ;3  @178
-    txa                          ;2  @180
-    lsr    a                     ;2  @182
-    lsr    a                     ;2  @184
-    lsr    a                     ;2  @186
-    ora    #ASCII_0_OFFSET
-
-    ; irmen: load X with ones, and store Y and A too, for easy printing afterwards
-    sty  decHundreds
-    sta  decTens
-    ldx  decOnes
-    rts                          ;6  @192   Y=hundreds, A = tens digit, X=ones digit
-
-
-HexToDec999; SUBROUTINE
-    sty    hexLow                ;3  @9
-    jmp    Start100s             ;3  @12
-
-Mod100Tab
-    .byte 0,56,12,56+12
-
-ShiftedBcdTab
-    .byte $00,$01,$02,$03,$04,$08,$09,$0A,$0B,$0C
-    .byte $10,$11,$12,$13,$14,$18,$19,$1A,$1B,$1C
-    .byte $20,$21,$22,$23,$24,$28,$29,$2A,$2B,$2C
-    .byte $30,$31,$32,$33,$34,$38,$39,$3A,$3B,$3C
-    .byte $40,$41,$42,$43,$44,$48,$49,$4A,$4B,$4C
-
-decTenThousands   	.byte  0
-decThousands    	.byte  0
-decHundreds		.byte  0
-decTens			.byte  0
-decOnes   		.byte  0
-			.byte  0		; zero-terminate the decimal output string
-
-    }}
-}
-
-asmsub  byte2decimal  (byte value @A) -> ubyte @Y, ubyte @A, ubyte @X  {
-	; ---- A (signed byte) to decimal string in Y/A/X  (100s in Y, 10s in A, 1s in X)
-	;      note: if the number is negative, you have to deal with the '-' yourself!
-	%asm {{
-		cmp  #0
-		bpl  +
-		eor  #255
-		clc
-		adc  #1
-+		jmp  ubyte2decimal
-	}}
-}
-
-asmsub  ubyte2hex  (ubyte value @A) -> 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
+		phx
+		ldy  #0
+		sty  P8ZP_SCRATCH_B1
+		jsr  conv.ubyte2decimal
+_output_byte_digits
+                ; hundreds?
+		cpy  #'0'
+		beq  +
 		pha
-		and  #$0f
-		tax
-		ldy  _hex_digits,x
+		tya
+		ldy  P8ZP_SCRATCH_B1
+		sta  string_out,y
 		pla
-		lsr  a
-		lsr  a
-		lsr  a
-		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
+		inc  P8ZP_SCRATCH_B1
+		; tens?
++		ldy  P8ZP_SCRATCH_B1
+                cmp  #'0'
+		beq  +
+		sta  string_out,y
+		iny
++               ; ones.
+                txa
+                sta  string_out,y
+                iny
+                lda  #0
+                sta  string_out,y
+                plx
+                rts
 	}}
 }
 
-asmsub  uword2hex  (uword value @AY) clobbers(A,Y)  {
-	; ---- convert 16 bit uword in A/Y into 4-character hexadecimal string 'uword2hex.output' (0-terminated)
+asmsub  str_b  (byte value @ A) clobbers(A,Y)  {
+	; ---- convert the byte in A in decimal string form, without left padding 0s
 	%asm {{
-		sta  P8ZP_SCRATCH_REG
-		tya
-		jsr  ubyte2hex
-		sta  output
-		sty  output+1
-		lda  P8ZP_SCRATCH_REG
-		jsr  ubyte2hex
-		sta  output+2
-		sty  output+3
-		rts
-output		.text  "0000", $00      ; 0-terminated output buffer (to make printing easier)
+            phx
+            ldy  #0
+            sty  P8ZP_SCRATCH_B1
+            cmp  #0
+            bpl  +
+            pha
+            lda  #'-'
+            sta  string_out
+            inc  P8ZP_SCRATCH_B1
+            pla
++	    jsr  conv.byte2decimal
+            bra  str_ub._output_byte_digits
+	}}
+}
+
+asmsub  str_ubhex  (ubyte value @ A) clobbers(A,Y)  {
+	; ---- convert the ubyte in A in hex string form
+	%asm {{
+            jsr  conv.ubyte2hex
+            sta  string_out
+            sty  string_out+1
+            lda  #0
+            sta  string_out+2
+            rts
+	}}
+}
+
+asmsub  str_ubbin  (ubyte value @ A) clobbers(A,Y)  {
+	; ---- convert the ubyte in A in binary string form
+	%asm {{
+	    sta  P8ZP_SCRATCH_B1
+	    ldy  #0
+	    sty  string_out+8
+	    ldy  #7
+-	    lsr  P8ZP_SCRATCH_B1
+            bcc  +
+            lda  #'1'
+            bne  _digit
++           lda  #'0'
+_digit      sta  string_out,y
+            dey
+	    bpl  -
+	    rts
+	}}
+}
+
+asmsub  str_uwbin  (uword value @ AY) clobbers(A,Y)  {
+	; ---- convert the uword in A/Y in binary string form
+	%asm {{
+	    sta  P8ZP_SCRATCH_REG
+	    tya
+	    jsr  str_ubbin
+	    ldy  #0
+	    sty  string_out+16
+	    ldy  #7
+-	    lsr  P8ZP_SCRATCH_REG
+            bcc  +
+            lda  #'1'
+            bne  _digit
++           lda  #'0'
+_digit      sta  string_out+8,y
+            dey
+	    bpl  -
+	    rts
+	}}
+}
+
+asmsub  str_uwhex  (uword value @ AY) clobbers(A,Y)  {
+	; ---- convert the uword in A/Y in hexadecimal string form (4 digits)
+	%asm {{
+            pha
+            tya
+            jsr  conv.ubyte2hex
+            sta  string_out
+            sty  string_out+1
+            pla
+            jsr  conv.ubyte2hex
+            sta  string_out+2
+            sty  string_out+3
+            lda  #0
+            sta  string_out+4
+            rts
+	}}
+}
+
+asmsub  str_uw0  (uword value @ AY) clobbers(A,Y)  {
+	; ---- convert the uword in A/Y in decimal string form, with left padding 0s (5 positions total)
+	%asm {{
+	    phx
+	    jsr  conv.uword2decimal
+	    ldy  #0
+-           lda  conv.uword2decimal.decTenThousands,y
+            sta  string_out,y
+            beq  +
+            iny
+            bne  -
++           plx
+	    rts
+	}}
+}
+
+asmsub  str_uw  (uword value @ AY) clobbers(A,Y)  {
+	; ---- convert the uword in A/Y in decimal string form, without left padding 0s
+	%asm {{
+	    phx
+	    jsr  conv.uword2decimal
+	    ldx  #0
+_output_digits
+	    ldy  #0
+-           lda  conv.uword2decimal.decTenThousands,y
+            beq  _allzero
+            cmp  #'0'
+            bne  _gotdigit
+            iny
+            bne  -
+_gotdigit   sta  string_out,x
+            inx
+            iny
+            lda  conv.uword2decimal.decTenThousands,y
+            bne  _gotdigit
+_end        lda  #0
+            sta  string_out,x
+            plx
+            rts
+
+_allzero    lda  #'0'
+            sta  string_out,x
+            inx
+            bne  _end
+	}}
+}
+
+asmsub  str_w  (word value @ AY) clobbers(A,Y)  {
+	; ---- convert the (signed) word in A/Y in decimal string form, without left padding 0's
+	%asm {{
+	    cpy  #0
+	    bpl  str_uw
+	    phx
+	    pha
+	    lda  #'-'
+	    sta  string_out
+            tya
+            eor  #255
+            tay
+            pla
+            eor  #255
+            clc
+            adc  #1
+            bcc  +
+            iny
++	    jsr  conv.uword2decimal
+	    ldx  #1
+	    bne  str_uw._output_digits
 	}}
 }
 
@@ -257,7 +231,7 @@ asmsub  any2uword(str string @AY) clobbers(Y) -> ubyte @A {
 	sta  P8ZP_SCRATCH_W1
 	sty  P8ZP_SCRATCH_W1+1
 	ldy  #0
-	lda  (P8ZP_SCRATCH_W1)
+	lda  (P8ZP_SCRATCH_W1),y
 	ldy  P8ZP_SCRATCH_W1+1
 	cmp  #'$'
 	beq  _hex
@@ -520,4 +494,243 @@ _stop
 	}}
 }
 
+
+; ----- low level number conversions to decimal strings ----
+
+asmsub  ubyte2decimal  (ubyte value @A) -> ubyte @Y, ubyte @A, ubyte @X  {
+	; ---- A to decimal string in Y/A/X  (100s in Y, 10s in A, 1s in X)
+	%asm {{
+		ldy  #uword2decimal.ASCII_0_OFFSET
+		bne  uword2decimal.hex_try200
+		rts
+	}}
+}
+
+asmsub  uword2decimal  (uword value @AY) -> ubyte @Y, ubyte @A, ubyte @X  {
+	;  ---- convert 16 bit uword in A/Y to decimal
+	;  output in uword2decimal.decTenThousands, decThousands, decHundreds, decTens, decOnes
+	;  (these are terminated by a zero byte so they can be easily printed)
+	;  also returns Y = 100's, A = 10's, X = 1's
+
+	%asm {{
+
+;Convert 16 bit Hex to Decimal (0-65535) Rev 2
+;By Omegamatrix    Further optimizations by tepples
+; routine from http://forums.nesdev.com/viewtopic.php?f=2&t=11341&start=15
+
+;HexToDec99
+; start in A
+; end with A = 10's, decOnes (also in X)
+
+;HexToDec255
+; start in A
+; end with Y = 100's, A = 10's, decOnes (also in X)
+
+;HexToDec999
+; start with A = high byte, Y = low byte
+; end with Y = 100's, A = 10's, decOnes (also in X)
+; requires 1 extra temp register on top of decOnes, could combine
+; these two if HexToDec65535 was eliminated...
+
+;HexToDec65535
+; start with A/Y (low/high) as 16 bit value
+; end with decTenThousand, decThousand, Y = 100's, A = 10's, decOnes (also in X)
+; (irmen: I store Y and A in decHundreds and decTens too, so all of it can be easily printed)
+
+
+ASCII_0_OFFSET 	= $30
+temp       	    = P8ZP_SCRATCH_B1	; byte in zeropage
+hexHigh      	= P8ZP_SCRATCH_W1	; byte in zeropage
+hexLow       	= P8ZP_SCRATCH_W1+1	; byte in zeropage
+
+
+HexToDec65535; SUBROUTINE
+    sty    hexHigh               ;3  @9
+    sta    hexLow                ;3  @12
+    tya
+    tax                          ;2  @14
+    lsr    a                     ;2  @16
+    lsr    a                     ;2  @18   integer divide 1024 (result 0-63)
+
+    cpx    #$A7                  ;2  @20   account for overflow of multiplying 24 from 43,000 ($A7F8) onward,
+    adc    #1                    ;2  @22   we can just round it to $A700, and the divide by 1024 is fine...
+
+    ;at this point we have a number 1-65 that we have to times by 24,
+    ;add to original sum, and Mod 1024 to get a remainder 0-999
+
+
+    sta    temp                  ;3  @25
+    asl    a                     ;2  @27
+    adc    temp                  ;3  @30  x3
+    tay                          ;2  @32
+    lsr    a                     ;2  @34
+    lsr    a                     ;2  @36
+    lsr    a                     ;2  @38
+    lsr    a                     ;2  @40
+    lsr    a                     ;2  @42
+    tax                          ;2  @44
+    tya                          ;2  @46
+    asl    a                     ;2  @48
+    asl    a                     ;2  @50
+    asl    a                     ;2  @52
+    clc                          ;2  @54
+    adc    hexLow                ;3  @57
+    sta    hexLow                ;3  @60
+    txa                          ;2  @62
+    adc    hexHigh               ;3  @65
+    sta    hexHigh               ;3  @68
+    ror    a                     ;2  @70
+    lsr    a                     ;2  @72
+    tay                          ;2  @74    integer divide 1,000 (result 0-65)
+
+    lsr    a                     ;2  @76    split the 1,000 and 10,000 digit
+    tax                          ;2  @78
+    lda    ShiftedBcdTab,x       ;4  @82
+    tax                          ;2  @84
+    rol    a                     ;2  @86
+    and    #$0F                  ;2  @88
+    ora    #ASCII_0_OFFSET
+    sta    decThousands          ;3  @91
+    txa                          ;2  @93
+    lsr    a                     ;2  @95
+    lsr    a                     ;2  @97
+    lsr    a                     ;2  @99
+    ora    #ASCII_0_OFFSET
+    sta    decTenThousands       ;3  @102
+
+    lda    hexLow                ;3  @105
+    cpy    temp                  ;3  @108
+    bmi    _doSubtract           ;2³ @110/111
+    beq    _useZero               ;2³ @112/113
+    adc    #23 + 24              ;2  @114
+_doSubtract
+    sbc    #23                   ;2  @116
+    sta    hexLow                ;3  @119
+_useZero
+    lda    hexHigh               ;3  @122
+    sbc    #0                    ;2  @124
+
+Start100s
+    and    #$03                  ;2  @126
+    tax                          ;2  @128   0,1,2,3
+    cmp    #2                    ;2  @130
+    rol    a                     ;2  @132   0,2,5,7
+    ora    #ASCII_0_OFFSET
+    tay                          ;2  @134   Y = Hundreds digit
+
+    lda    hexLow                ;3  @137
+    adc    Mod100Tab,x           ;4  @141    adding remainder of 256, 512, and 256+512 (all mod 100)
+    bcs    hex_doSub200             ;2³ @143/144
+
+hex_try200
+    cmp    #200                  ;2  @145
+    bcc    hex_try100               ;2³ @147/148
+hex_doSub200
+    iny                          ;2  @149
+    iny                          ;2  @151
+    sbc    #200                  ;2  @153
+hex_try100
+    cmp    #100                  ;2  @155
+    bcc    HexToDec99            ;2³ @157/158
+    iny                          ;2  @159
+    sbc    #100                  ;2  @161
+
+HexToDec99; SUBROUTINE
+    lsr    a                     ;2  @163
+    tax                          ;2  @165
+    lda    ShiftedBcdTab,x       ;4  @169
+    tax                          ;2  @171
+    rol    a                     ;2  @173
+    and    #$0F                  ;2  @175
+    ora    #ASCII_0_OFFSET
+    sta    decOnes               ;3  @178
+    txa                          ;2  @180
+    lsr    a                     ;2  @182
+    lsr    a                     ;2  @184
+    lsr    a                     ;2  @186
+    ora    #ASCII_0_OFFSET
+
+    ; irmen: load X with ones, and store Y and A too, for easy printing afterwards
+    sty  decHundreds
+    sta  decTens
+    ldx  decOnes
+    rts                          ;6  @192   Y=hundreds, A = tens digit, X=ones digit
+
+
+HexToDec999; SUBROUTINE
+    sty    hexLow                ;3  @9
+    jmp    Start100s             ;3  @12
+
+Mod100Tab
+    .byte 0,56,12,56+12
+
+ShiftedBcdTab
+    .byte $00,$01,$02,$03,$04,$08,$09,$0A,$0B,$0C
+    .byte $10,$11,$12,$13,$14,$18,$19,$1A,$1B,$1C
+    .byte $20,$21,$22,$23,$24,$28,$29,$2A,$2B,$2C
+    .byte $30,$31,$32,$33,$34,$38,$39,$3A,$3B,$3C
+    .byte $40,$41,$42,$43,$44,$48,$49,$4A,$4B,$4C
+
+decTenThousands   	.byte  0
+decThousands    	.byte  0
+decHundreds		.byte  0
+decTens			.byte  0
+decOnes   		.byte  0
+			.byte  0		; zero-terminate the decimal output string
+
+    }}
+}
+
+asmsub  byte2decimal  (byte value @A) -> ubyte @Y, ubyte @A, ubyte @X  {
+	; ---- A (signed byte) to decimal string in Y/A/X  (100s in Y, 10s in A, 1s in X)
+	;      note: if the number is negative, you have to deal with the '-' yourself!
+	%asm {{
+		cmp  #0
+		bpl  +
+		eor  #255
+		clc
+		adc  #1
++		jmp  ubyte2decimal
+	}}
+}
+
+asmsub  ubyte2hex  (ubyte value @A) -> 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
+		ldy  _hex_digits,x
+		pla
+		lsr  a
+		lsr  a
+		lsr  a
+		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
+	}}
+}
+
+asmsub  uword2hex  (uword value @AY) clobbers(A,Y)  {
+	; ---- convert 16 bit uword in A/Y into 4-character hexadecimal string 'uword2hex.output' (0-terminated)
+	%asm {{
+		sta  P8ZP_SCRATCH_REG
+		tya
+		jsr  ubyte2hex
+		sta  output
+		sty  output+1
+		lda  P8ZP_SCRATCH_REG
+		jsr  ubyte2hex
+		sta  output+2
+		sty  output+3
+		rts
+output		.text  "0000", $00      ; 0-terminated output buffer (to make printing easier)
+	}}
+}
+
 }

compiler/res/prog8lib/cx16/floats.p8

@@ -4,15 +4,17 @@
 ;
 ; indent format: TABS, size=8
 
-%target cx16
 %option enable_floats
 
 floats {
-	; ---- this block contains C-64 floating point related functions ----
+	; ---- this block contains C-64 compatible floating point related functions ----
+	;      the addresses are from cx16 V39 emulator and roms! they won't work on older versions.
 
         const float  PI     = 3.141592653589793
         const float  TWOPI  = 6.283185307179586
 
+        ubyte[5] tempvar_swap_float     ; used for some swap() operations
+
 
 ; ---- ROM float functions ----
 
@@ -43,46 +45,44 @@ romsub $fe1e = NORMAL() clobbers(A,X,Y)                     ; normalize fac1 (?)
 romsub $fe24 = LOG() clobbers(A,X,Y)                        ; fac1 = LN(fac1)  (natural log)
 romsub $fe27 = FMULT(uword mflpt @ AY) clobbers(A,X,Y)      ; fac1 *= mflpt value from A/Y
 romsub $fe2a = FMULTT() clobbers(A,X,Y)                     ; fac1 *= fac2
-romsub $fe33 = CONUPK(uword mflpt @ AY) clobbers(A,Y)       ; load mflpt value from memory  in A/Y into fac2
-romsub $fe36 = MUL10() clobbers(A,X,Y)                      ; fac1 *= 10
-romsub $fe3c = DIV10() clobbers(A,X,Y)                      ; fac1 /= 10 , CAUTION: result is always positive!
-romsub $fe3f = FDIV(uword mflpt @ AY) clobbers(A,X,Y)       ; fac1 = mflpt in A/Y / fac1  (remainder in fac2)
-romsub $fe42 = FDIVT() clobbers(A,X,Y)                      ; fac1 = fac2/fac1  (remainder in fac2)  mind the order of the operands
+romsub $fe30 = CONUPK(uword mflpt @ AY) clobbers(A,X,Y)     ; load mflpt value from memory  in A/Y into fac2
+romsub $fe33 = MUL10() clobbers(A,X,Y)                      ; fac1 *= 10
+romsub $fe36 = DIV10() clobbers(A,X,Y)                      ; fac1 /= 10 , CAUTION: result is always positive!
+romsub $fe39 = FDIV(uword mflpt @ AY) clobbers(A,X,Y)       ; fac1 = mflpt in A/Y / fac1  (remainder in fac2)
+romsub $fe3c = FDIVT() clobbers(A,X,Y)                      ; fac1 = fac2/fac1  (remainder in fac2)  mind the order of the operands
 
-romsub $fe48 = MOVFM(uword mflpt @ AY) clobbers(A,Y)        ; load mflpt value from memory  in A/Y into fac1
-romsub $fe4b = MOVMF(uword mflpt @ XY) clobbers(A,Y)        ; store fac1 to memory  X/Y as 5-byte mflpt
-romsub $fe4e = MOVFA() clobbers(A,X)                        ; copy fac2 to fac1
-romsub $fe51 = MOVAF() clobbers(A,X)                        ; copy fac1 to fac2  (rounded)
-romsub $fe54 = MOVEF() clobbers(A,X)                        ; copy fac1 to fac2
-romsub $fe5a = SIGN() -> ubyte @ A                          ; SIGN(fac1) to A, $ff, $0, $1 for negative, zero, positive
-romsub $fe5d = SGN() clobbers(A,X,Y)                        ; fac1 = SGN(fac1), result of SIGN (-1, 0 or 1)
-romsub $fe60 = FREADSA(byte value @ A) clobbers(A,X,Y)      ; 8 bit signed A -> float in fac1
-romsub $fe6c = ABS()                                        ; fac1 = ABS(fac1)
-romsub $fe6f = 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 $fe78 = INT() clobbers(A,X,Y)                        ; INT() truncates, use FADDH first to round instead of trunc
-romsub $fe7e = FINLOG(byte value @A) clobbers (A, X, Y)           ; fac1 += signed byte in A
-romsub $fe81 = FOUT() clobbers(X) -> uword @ AY             ; fac1 -> string, address returned in AY
-romsub $fe8a = SQR() clobbers(A,X,Y)                        ; fac1 = SQRT(fac1)
-romsub $fe8d = FPWRT() clobbers(A,X,Y)                      ; fac1 = fac2 ** fac1
-; note: there is no FPWR() on the Cx16
-romsub $fe93 = NEGOP() clobbers(A)                          ; switch the sign of fac1
-romsub $fe96 = EXP() clobbers(A,X,Y)                        ; fac1 = EXP(fac1)  (e ** fac1)
-romsub $fe9f = RND2(byte value @A) clobbers(A,X,Y)                ; fac1 = RND(A) float random number generator
-romsub $fea2 = RND() clobbers(A,X,Y)                        ; fac1 = RND(fac1) float random number generator
-romsub $fea5 = COS() clobbers(A,X,Y)                        ; fac1 = COS(fac1)
-romsub $fea8 = SIN() clobbers(A,X,Y)                        ; fac1 = SIN(fac1)
-romsub $feab = TAN() clobbers(A,X,Y)                        ; fac1 = TAN(fac1)
-romsub $feae = ATN() clobbers(A,X,Y)                        ; fac1 = ATN(fac1)
+romsub $fe42 = MOVFM(uword mflpt @ AY) clobbers(A,X,Y)      ; load mflpt value from memory  in A/Y into fac1
+romsub $fe45 = MOVMF(uword mflpt @ XY) clobbers(A,X,Y)      ; store fac1 to memory  X/Y as 5-byte mflpt
+romsub $fe48 = MOVFA() clobbers(A,X)                        ; copy fac2 to fac1
+romsub $fe4b = MOVAF() clobbers(A,X)                        ; copy fac1 to fac2  (rounded)
+romsub $fe4e = MOVEF() clobbers(A,X)                        ; copy fac1 to fac2
+romsub $fe54 = SIGN() clobbers(X,Y) -> ubyte @ A            ; SIGN(fac1) to A, $ff, $0, $1 for negative, zero, positive
+romsub $fe57 = SGN() clobbers(A,X,Y)                        ; fac1 = SGN(fac1), result of SIGN (-1, 0 or 1)
+romsub $fe5a = FREADSA(byte value @ A) clobbers(A,X,Y)      ; 8 bit signed A -> float in fac1
+romsub $fe66 = ABS() clobbers(A,X,Y)                        ; fac1 = ABS(fac1)
+romsub $fe69 = 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 $fe72 = INT() clobbers(A,X,Y)                        ; INT() truncates, use FADDH first to round instead of trunc
+romsub $fe78 = FINLOG(byte value @A) clobbers (A, X, Y)           ; fac1 += signed byte in A
+romsub $fe7b = FOUT() clobbers(X) -> uword @ AY             ; fac1 -> string, address returned in AY
+romsub $fe81 = SQR() clobbers(A,X,Y)                        ; fac1 = SQRT(fac1)
+romsub $fe84 = FPWRT() clobbers(A,X,Y)                      ; fac1 = fac2 ** fac1
+romsub $fe8a = NEGOP() clobbers(A)                          ; switch the sign of fac1 (fac1 = -fac1)
+romsub $fe8d = EXP() clobbers(A,X,Y)                        ; fac1 = EXP(fac1)  (e ** fac1)
+romsub $fe96 = RND() clobbers(A,X,Y)                        ; fac1 = RND(fac1) float random number generator
+romsub $fe99 = COS() clobbers(A,X,Y)                        ; fac1 = COS(fac1)
+romsub $fe9c = SIN() clobbers(A,X,Y)                        ; fac1 = SIN(fac1)
+romsub $fe9f = TAN() clobbers(A,X,Y)                        ; fac1 = TAN(fac1)
+romsub $fea2 = ATN() clobbers(A,X,Y)                        ; fac1 = ATN(fac1)
 
 
 asmsub  GIVUAYFAY  (uword value @ AY) clobbers(A,X,Y)  {
 	; ---- unsigned 16 bit word in A/Y (lo/hi) to fac1
 	%asm {{
         phx
-        sta  P8ZP_SCRATCH_W2
+        sta  _tmp
         sty  P8ZP_SCRATCH_B1
         tya
-        ldy  P8ZP_SCRATCH_W2
+        ldy  _tmp
         jsr  GIVAYF                 ; load it as signed... correct afterwards
         lda  P8ZP_SCRATCH_B1
 	    bpl  +
@@ -91,6 +91,7 @@ asmsub  GIVUAYFAY  (uword value @ AY) clobbers(A,X,Y)  {
 	    jsr  FADD
 +	    plx
         rts
+_tmp        .byte 0
 _flt65536    .byte 145,0,0,0,0       ; 65536.0
 	}}
 }
@@ -128,6 +129,14 @@ asmsub  GETADRAY  () clobbers(X) -> uword @ AY  {
 	}}
 }
 
+asmsub  FREADUY (ubyte value @Y) {
+    ; -- 8 bit unsigned Y -> float in fac1
+    %asm {{
+        lda  #0
+        jmp  GIVAYF
+    }}
+}
+
 sub  print_f  (float value) {
 	; ---- prints the floating point value (without a newline).
 	%asm {{
@@ -149,7 +158,7 @@ sub  print_f  (float value) {
 	}}
 }
 
-%asminclude "library:c64/floats.asm", ""
-%asminclude "library:c64/floats_funcs.asm", ""
+%asminclude "library:c64/floats.asm"
+%asminclude "library:c64/floats_funcs.asm"
 
 }

compiler/res/prog8lib/cx16/gfx2.p8

@@ -1,33 +1,41 @@
-%target cx16
-
-; Bitmap pixel graphics module for the CommanderX16
+; Bitmap pixel graphics routines for the CommanderX16
 ; Custom routines to use the full-screen 640x480 and 320x240 screen modes.
-; This only works on the Cx16. No text layer is currently shown, text can be drawn as part of the bitmap itself.
-; Note: for compatible graphics code that words on C64 too, use the "graphics" module instead.
-; Note: there is no color palette manipulation here, you have to do that yourself or use the "palette" module.
+; (These modes are not supported by the documented GRAPH_xxxx kernal routines)
+;
+; No text layer is currently shown, text can be drawn as part of the bitmap itself.
+; Note: for similar graphics routines that also work on the C-64, use the "graphics" module instead.
+; Note: for color palette manipulation, use the "palette" module or write Vera registers yourself.
+; Note: this library implements code for various resolutions and color depths. This takes up memory.
+;       If you're memory constrained you should probably not use this built-in library,
+;       but make a copy in your project only containing the code for the required resolution.
+;
+;
+; SCREEN MODE LIST:
+;   mode 0 = reset back to default text mode
+;   mode 1 = bitmap 320 x 240 monochrome
+;   mode 2 = bitmap 320 x 240 x 4c (TODO not yet implemented)
+;   mode 3 = bitmap 320 x 240 x 16c (TODO not yet implemented)
+;   mode 4 = bitmap 320 x 240 x 256c
+;   mode 5 = bitmap 640 x 480 monochrome
+;   mode 6 = bitmap 640 x 480 x 4c
+;   higher color dephts in highres are not supported due to lack of VRAM
+
 
 ; TODO can we make a FB vector table and emulation routines for the Cx16s' GRAPH_init() call? to replace the builtin 320x200 fb driver?
 
 gfx2 {
 
     ; read-only control variables:
-    ubyte active_mode = 255
+    ubyte active_mode = 0
     uword width = 0
     uword height = 0
     ubyte bpp = 0
     ubyte monochrome_dont_stipple_flag = false            ; set to false to enable stippling mode in monochrome displaymodes
 
     sub screen_mode(ubyte mode) {
-        ; mode 0 = bitmap 320 x 240 x 1c monochrome
-        ; mode 1 = bitmap 320 x 240 x 256c
-        ; mode 128 = bitmap 640 x 480 x 1c monochrome
-        ; ...other modes?
-
-        ; copy the lower-case charset to the upper part of the vram, so we can use it later to plot text
-
         when mode {
-            0 -> {
-                ; 320 x 240 x 1c
+            1 -> {
+                ; lores monochrome
                 cx16.VERA_DC_VIDEO = (cx16.VERA_DC_VIDEO & %11001111) | %00100000      ; enable only layer 1
                 cx16.VERA_DC_HSCALE = 64
                 cx16.VERA_DC_VSCALE = 64
@@ -38,8 +46,9 @@ gfx2 {
                 height = 240
                 bpp = 1
             }
-            1 -> {
-                ; 320 x 240 x 256c
+            ; TODO modes 2, 3 not yet implemented
+            4 -> {
+                ; lores 256c
                 cx16.VERA_DC_VIDEO = (cx16.VERA_DC_VIDEO & %11001111) | %00100000      ; enable only layer 1
                 cx16.VERA_DC_HSCALE = 64
                 cx16.VERA_DC_VSCALE = 64
@@ -50,8 +59,8 @@ gfx2 {
                 height = 240
                 bpp = 8
             }
-            128 -> {
-                ; 640 x 480 x 1c
+            5 -> {
+                ; highres monochrome
                 cx16.VERA_DC_VIDEO = (cx16.VERA_DC_VIDEO & %11001111) | %00100000      ; enable only layer 1
                 cx16.VERA_DC_HSCALE = 128
                 cx16.VERA_DC_VSCALE = 128
@@ -62,13 +71,26 @@ gfx2 {
                 height = 480
                 bpp = 1
             }
-            255 -> {
+            6 -> {
+                ; highres 4c
+                cx16.VERA_DC_VIDEO = (cx16.VERA_DC_VIDEO & %11001111) | %00100000      ; enable only layer 1
+                cx16.VERA_DC_HSCALE = 128
+                cx16.VERA_DC_VSCALE = 128
+                cx16.VERA_L1_CONFIG = %00000101
+                cx16.VERA_L1_MAPBASE = 0
+                cx16.VERA_L1_TILEBASE = %00000001
+                width = 640
+                height = 480
+                bpp = 2
+            }
+            else -> {
                 ; back to default text mode and colors
                 cx16.VERA_CTRL = %10000000      ; reset VERA and palette
                 c64.CINT()      ; back to text mode
                 width = 0
                 height = 0
                 bpp = 0
+                mode = 0
             }
         }
 
@@ -81,21 +103,28 @@ gfx2 {
         monochrome_stipple(false)
         position(0, 0)
         when active_mode {
-            0 -> {
-                ; 320 x 240 x 1c
+            1 -> {
+                ; lores monochrome
                 repeat 240/2/8
                     cs_innerloop640()
             }
-            1 -> {
-                ; 320 x 240 x 256c
+            ; TODO mode 2, 3
+            4 -> {
+                ; lores 256c
                 repeat 240/2
                     cs_innerloop640()
             }
-            128 -> {
-                ; 640 x 480 x 1c
+            5 -> {
+                ; highres monochrome
                 repeat 480/8
                     cs_innerloop640()
             }
+            6 -> {
+                ; highres 4c
+                repeat 480/4
+                    cs_innerloop640()
+            }
+            ; modes 7 and 8 not supported due to lack of VRAM
         }
         position(0, 0)
     }
@@ -130,35 +159,13 @@ gfx2 {
         if length==0
             return
         when active_mode {
-            1 -> {
-                ; 8bpp mode
-                position(x, y)
-                %asm {{
-                    lda  color
-                    phx
-                    ldx  length+1
-                    beq  +
-                    ldy  #0
--                   sta  cx16.VERA_DATA0
-                    iny
-                    bne  -
-                    dex
-                    bne  -
-+                   ldy  length     ; remaining
-                    beq  +
--                   sta  cx16.VERA_DATA0
-                    dey
-                    bne  -
-+                   plx
-                }}
-            }
-            0, 128 -> {
-                ; 1 bpp mode
+            1, 5 -> {
+                ; monochrome modes, either resolution
                 ubyte separate_pixels = (8-lsb(x)) & 7
                 if separate_pixels as uword > length
                     separate_pixels = lsb(length)
                 repeat separate_pixels {
-                    ; this could be  optimized by setting this byte in 1 go but probably not worth it due to code size
+                    ; TODO optimize this by writing a masked byte in 1 go
                     plot(x, y, color)
                     x++
                 }
@@ -200,116 +207,188 @@ _loop                   lda  length
 _done
                     }}
                     repeat separate_pixels {
-                        ; this could be  optimized by setting this byte in 1 go but probably not worth it due to code size
+                        ; TODO optimize this by writing a masked byte in 1 go
                         plot(x, y, color)
                         x++
                     }
                 }
-                cx16.VERA_ADDR_H = (cx16.VERA_ADDR_H & %00000111)   ; vera auto-increment off again
+                cx16.VERA_ADDR_H &= %00000111   ; vera auto-increment off again
+            }
+            4 -> {
+                ; lores 256c
+                position(x, y)
+                %asm {{
+                    lda  color
+                    phx
+                    ldx  length+1
+                    beq  +
+                    ldy  #0
+-                   sta  cx16.VERA_DATA0
+                    iny
+                    bne  -
+                    dex
+                    bne  -
++                   ldy  length     ; remaining
+                    beq  +
+-                   sta  cx16.VERA_DATA0
+                    dey
+                    bne  -
++                   plx
+                }}
+            }
+            6 -> {
+                ; highres 4c
+                ; TODO also mostly usable for lores 4c?
+                color &= 3
+                ubyte[4] colorbits
+                ubyte ii
+                for ii in 3 downto 0 {
+                    colorbits[ii] = color
+                    color <<= 2
+                }
+                void addr_mul_24_for_highres_4c(y, x)      ; 24 bits result is in r0 and r1L (highest byte)
+                %asm {{
+                    lda  cx16.VERA_ADDR_H
+                    and  #%00000111         ; no auto advance
+                    sta  cx16.VERA_ADDR_H
+                    stz  cx16.VERA_CTRL     ; setup vera addr 0
+                    lda  cx16.r1
+                    and  #1
+                    sta  cx16.VERA_ADDR_H
+                    lda  cx16.r0
+                    sta  cx16.VERA_ADDR_L
+                    lda  cx16.r0+1
+                    sta  cx16.VERA_ADDR_M
+                    phx
+                    ldx  x
+                }}
+
+                repeat length {
+                    %asm {{
+                        txa
+                        and  #3
+                        tay
+                        lda  cx16.VERA_DATA0
+                        and  gfx2.plot.mask4c,y
+                        ora  colorbits,y
+                        sta  cx16.VERA_DATA0
+                        cpy  #%00000011         ; next vera byte?
+                        bne  ++
+                        inc  cx16.VERA_ADDR_L
+                        bne  ++
+                        inc  cx16.VERA_ADDR_M
++                       bne  +
+                        inc  cx16.VERA_ADDR_H
++                       inx                     ; next pixel
+                    }}
+                }
+
+                %asm {{
+                    plx
+                }}
             }
         }
     }
 
     sub vertical_line(uword x, uword y, uword height, ubyte color) {
-        position(x,y)
-        if active_mode==1 {
-            ; set vera auto-increment to 320 pixel increment (=next line)
-            cx16.VERA_ADDR_H = (cx16.VERA_ADDR_H & %00000111) | (14<<4)
-            %asm {{
-                ldy  height
-                beq  +
-                lda  color
--               sta  cx16.VERA_DATA0
-                dey
-                bne  -
-+
-            }}
-            return
-        }
-
-        ; note for the 1 bpp modes we can't use vera's auto increment mode because we have to 'or' the pixel data in place.
-        cx16.VERA_ADDR_H = (cx16.VERA_ADDR_H & %00000111)   ; no auto advance
-        cx16.r15 = gfx2.plot.bits[x as ubyte & 7]           ; bitmask
-        if active_mode>=128
-            cx16.r14 = 640/8
-        else
-            cx16.r14 = 320/8
-        if color {
-            if monochrome_dont_stipple_flag {
-                repeat height {
-                    %asm {{
-                        lda  cx16.VERA_DATA0
-                        ora  cx16.r15
-                        sta  cx16.VERA_DATA0
-                        lda  cx16.VERA_ADDR_L
-                        clc
-                        adc  cx16.r14                 ; advance vera ptr to go to the next line
-                        sta  cx16.VERA_ADDR_L
-                        lda  cx16.VERA_ADDR_M
-                        adc  #0
-                        sta  cx16.VERA_ADDR_M
-                        ; lda  cx16.VERA_ADDR_H     ; the bitmap size is small enough to not have to deal with the _H part.
-                        ; adc  #0
-                        ; sta  cx16.VERA_ADDR_H
-                    }}
+        when active_mode {
+            1, 5 -> {
+                ; monochrome, lo-res
+                cx16.r15L = gfx2.plot.bits[x as ubyte & 7]           ; bitmask
+                if color {
+                    if monochrome_dont_stipple_flag {
+                        ; draw continuous line.
+                        position2(x,y,true)
+                        if active_mode==1
+                            set_both_strides(11)    ; 40 increment = 1 line in 320 px monochrome
+                        else
+                            set_both_strides(12)    ; 80 increment = 1 line in 640 px monochrome
+                        repeat height {
+                            %asm {{
+                                lda  cx16.VERA_DATA0
+                                ora  cx16.r15L
+                                sta  cx16.VERA_DATA1
+                            }}
+                        }
+                    } else {
+                        ; draw stippled line.
+                        if x&1 {
+                            y++
+                            height--
+                        }
+                        position2(x,y,true)
+                        if active_mode==1
+                            set_both_strides(12)    ; 80 increment = 2 line in 320 px monochrome
+                        else
+                            set_both_strides(13)    ; 160 increment = 2 line in 640 px monochrome
+                        repeat height/2 {
+                            %asm {{
+                                lda  cx16.VERA_DATA0
+                                ora  cx16.r15L
+                                sta  cx16.VERA_DATA1
+                            }}
+                        }
+                    }
+                } else {
+                    position2(x,y,true)
+                    cx16.r15 = ~cx16.r15    ; erase pixels
+                    if active_mode==1
+                        set_both_strides(11)    ; 40 increment = 1 line in 320 px monochrome
+                    else
+                        set_both_strides(12)    ; 80 increment = 1 line in 640 px monochrome
+                    repeat height {
+                        %asm {{
+                            lda  cx16.VERA_DATA0
+                            and  cx16.r15L
+                            sta  cx16.VERA_DATA1
+                        }}
+                    }
                 }
-            } else {
-                ; stippling.
-                height = (height+1)/2
+            }
+            4 -> {
+                ; lores 256c
+                ; set vera auto-increment to 320 pixel increment (=next line)
+                position(x,y)
+                cx16.VERA_ADDR_H = cx16.VERA_ADDR_H & %00000111 | (14<<4)
                 %asm {{
-                    lda x
-                    eor y
-                    and #1
-                    bne +
-                    lda  cx16.VERA_ADDR_L
-                    clc
-                    adc  cx16.r14                ; advance vera ptr to go to the next line for correct stipple pattern
-                    sta  cx16.VERA_ADDR_L
-                    lda  cx16.VERA_ADDR_M
-                    adc  #0
-                    sta  cx16.VERA_ADDR_M
-+
-                    asl  cx16.r14
                     ldy  height
                     beq  +
--                   lda  cx16.VERA_DATA0
-                    ora  cx16.r15
-                    sta  cx16.VERA_DATA0
-                    lda  cx16.VERA_ADDR_L
-                    clc
-                    adc  cx16.r14               ; advance vera data ptr to go to the next-next line
-                    sta  cx16.VERA_ADDR_L
-                    lda  cx16.VERA_ADDR_M
-                    adc  #0
-                    sta  cx16.VERA_ADDR_M
-                    ; lda  cx16.VERA_ADDR_H      ; the bitmap size is small enough to not have to deal with the _H part.
-                    ; adc  #0
-                    ; sta  cx16.VERA_ADDR_H
+                    lda  color
+-                   sta  cx16.VERA_DATA0
                     dey
                     bne  -
 +
                 }}
             }
-        } else {
-            cx16.r15 = ~cx16.r15
-            repeat height {
-                %asm {{
-                    lda  cx16.VERA_DATA0
-                    and  cx16.r15
-                    sta  cx16.VERA_DATA0
-                    lda  cx16.VERA_ADDR_L
-                    clc
-                    adc  cx16.r14             ; advance vera data ptr to go to the next line
-                    sta  cx16.VERA_ADDR_L
-                    lda  cx16.VERA_ADDR_M
-                    adc  #0
-                    sta  cx16.VERA_ADDR_M
-                    ; lda  cx16.VERA_ADDR_H      ; the bitmap size is small enough to not have to deal with the _H part.
-                    ; adc  #0
-                    ; sta  cx16.VERA_ADDR_H
-                }}
+            6 -> {
+                ; highres 4c
+                ; use TWO vera adress pointers simultaneously one for reading, one for writing, so auto-increment is possible
+                if height==0
+                    return
+                position2(x,y,true)
+                set_both_strides(13)    ; 160 increment = 1 line in 640 px 4c mode
+                color &= 3
+                color <<= gfx2.plot.shift4c[lsb(x) & 3]
+                ubyte mask = gfx2.plot.mask4c[lsb(x) & 3]
+                repeat height {
+                    %asm {{
+                        lda  cx16.VERA_DATA0
+                        and  mask
+                        ora  color
+                        sta  cx16.VERA_DATA1
+                    }}
+                }
             }
         }
+
+        sub set_both_strides(ubyte stride) {
+            stride <<= 4
+            cx16.VERA_CTRL = 0
+            cx16.VERA_ADDR_H = cx16.VERA_ADDR_H & %00000111 | stride
+            cx16.VERA_CTRL = 1
+            cx16.VERA_ADDR_H = cx16.VERA_ADDR_H & %00000111 | stride
+        }
+
     }
 
     sub line(uword @zp x1, uword @zp y1, uword @zp x2, uword @zp y2, ubyte color) {
@@ -320,42 +399,41 @@ _done
             swap(x1, x2)
             swap(y1, y2)
         }
-        word @zp dx = x2-x1 as word
-        word @zp dy = y2-y1 as word
+        word @zp dx = (x2 as word)-x1
+        word @zp dy = (y2 as word)-y1
 
         if dx==0 {
-            vertical_line(x1, y1, abs(dy)+1 as uword, color)
+            vertical_line(x1, y1, abs(dy) as uword +1, color)
             return
         }
         if dy==0 {
             if x1>x2
                 x1=x2
-            horizontal_line(x1, y1, abs(dx)+1 as uword, color)
+            horizontal_line(x1, y1, abs(dx) as uword +1, color)
             return
         }
 
-        ; TODO rewrite the rest in optimized assembly (or reuse GRAPH_draw_line if we can get the FB replacement vector layer working)
         word @zp d = 0
-        ubyte positive_ix = true
+        cx16.r13 = true      ; 'positive_ix'
         if dx < 0 {
             dx = -dx
-            positive_ix = false
+            cx16.r13 = false
         }
-        dx *= 2
-        dy *= 2
+        word @zp dx2 = dx*2
+        word @zp dy2 = dy*2
         cx16.r14 = x1       ; internal plot X
 
         if dx >= dy {
-            if positive_ix {
+            if cx16.r13 {
                 repeat {
                     plot(cx16.r14, y1, color)
                     if cx16.r14==x2
                         return
                     cx16.r14++
-                    d += dy
+                    d += dy2
                     if d > dx {
                         y1++
-                        d -= dx
+                        d -= dx2
                     }
                 }
             } else {
@@ -364,25 +442,25 @@ _done
                     if cx16.r14==x2
                         return
                     cx16.r14--
-                    d += dy
+                    d += dy2
                     if d > dx {
                         y1++
-                        d -= dx
+                        d -= dx2
                     }
                 }
             }
         }
         else {
-            if positive_ix {
+            if cx16.r13 {
                 repeat {
                     plot(cx16.r14, y1, color)
                     if y1 == y2
                         return
                     y1++
-                    d += dx
+                    d += dx2
                     if d > dy {
                         cx16.r14++
-                        d -= dy
+                        d -= dy2
                     }
                 }
             } else {
@@ -391,10 +469,10 @@ _done
                     if y1 == y2
                         return
                     y1++
-                    d += dx
+                    d += dx2
                     if d > dy {
                         cx16.r14--
-                        d -= dy
+                        d -= dy2
                     }
                 }
             }
@@ -468,79 +546,160 @@ _done
 
     sub plot(uword @zp x, uword y, ubyte color) {
         ubyte[8] bits = [128, 64, 32, 16, 8, 4, 2, 1]
-        uword addr
-        ubyte value
+        ubyte[4] mask4c = [%00111111, %11001111, %11110011, %11111100]
+        ubyte[4] shift4c = [6,4,2,0]
 
         when active_mode {
-            0 -> {
-                %asm {{
-                    lda  x
-                    eor  y
-                    ora  monochrome_dont_stipple_flag
-                    and  #1
-                }}
-                if_nz {
-                    addr = x/8 + y*(320/8)
-                    value = bits[lsb(x)&7]
-                    if color
-                        cx16.vpoke_or(0, addr, value)
-                    else {
-                        value = ~value
-                        cx16.vpoke_and(0, addr, value)
-                    }
-                }
-            }
-            128 -> {
-                %asm {{
-                    lda  x
-                    eor  y
-                    ora  monochrome_dont_stipple_flag
-                    and  #1
-                }}
-                if_nz {
-                    addr = x/8 + y*(640/8)
-                    value = bits[lsb(x)&7]
-                    if color
-                        cx16.vpoke_or(0, addr, value)
-                    else {
-                        value = ~value
-                        cx16.vpoke_and(0, addr, value)
-                    }
-                }
-            }
             1 -> {
-                void addr_mul_320_add_24(y, x)      ; 24 bits result is in r0 and r1L
-                value = lsb(cx16.r1)
-                cx16.vpoke(value, cx16.r0, color)
-                ; activate vera auto-increment mode so next_pixel() can be used after this
-                cx16.VERA_ADDR_H = (cx16.VERA_ADDR_H & %00000111) | %00010000
-                color = cx16.VERA_DATA0
+                ; lores monochrome
+                %asm {{
+                    lda  x
+                    eor  y
+                    ora  monochrome_dont_stipple_flag
+                    and  #1
+                }}
+                if_nz {
+                    cx16.r0L = lsb(x) & 7       ; xbits
+                    x /= 8
+                    x += y*(320/8)
+                    %asm {{
+                        stz  cx16.VERA_CTRL
+                        stz  cx16.VERA_ADDR_H
+                        lda  x+1
+                        sta  cx16.VERA_ADDR_M
+                        lda  x
+                        sta  cx16.VERA_ADDR_L
+                        ldy  cx16.r0L       ; xbits
+                        lda  bits,y
+                        ldy  color
+                        beq  +
+                        tsb  cx16.VERA_DATA0
+                        bra  ++
++                       trb  cx16.VERA_DATA0
++
+                    }}
+                }
+            }
+            ; TODO mode 2,3
+            4 -> {
+                ; lores 256c
+                void addr_mul_24_for_lores_256c(y, x)      ; 24 bits result is in r0 and r1L (highest byte)
+                %asm {{
+                    stz  cx16.VERA_CTRL
+                    lda  cx16.r1
+                    ora  #%00010000     ; enable auto-increment so next_pixel() can be used after this
+                    sta  cx16.VERA_ADDR_H
+                    lda  cx16.r0+1
+                    sta  cx16.VERA_ADDR_M
+                    lda  cx16.r0
+                    sta  cx16.VERA_ADDR_L
+                    lda  color
+                    sta  cx16.VERA_DATA0
+                }}
+            }
+            5 -> {
+                ; highres monochrome
+                %asm {{
+                    lda  x
+                    eor  y
+                    ora  monochrome_dont_stipple_flag
+                    and  #1
+                }}
+                if_nz {
+                    cx16.r0L = lsb(x) & 7       ; xbits
+                    x /= 8
+                    x += y*(640/8)
+                    %asm {{
+                        stz  cx16.VERA_CTRL
+                        stz  cx16.VERA_ADDR_H
+                        lda  x+1
+                        sta  cx16.VERA_ADDR_M
+                        lda  x
+                        sta  cx16.VERA_ADDR_L
+                        ldy  cx16.r0L           ; xbits
+                        lda  bits,y
+                        ldy  color
+                        beq  +
+                        tsb  cx16.VERA_DATA0
+                        bra  ++
++                       trb  cx16.VERA_DATA0
++
+                    }}
+                }
+            }
+            6 -> {
+                ; highres 4c
+                ; TODO also mostly usable for lores 4c?
+                void addr_mul_24_for_highres_4c(y, x)      ; 24 bits result is in r0 and r1L (highest byte)
+                cx16.r2L = lsb(x) & 3       ; xbits
+                color &= 3
+                color <<= shift4c[cx16.r2L]
+                %asm {{
+                    stz  cx16.VERA_CTRL
+                    lda  cx16.r1L
+                    sta  cx16.VERA_ADDR_H
+                    lda  cx16.r0H
+                    sta  cx16.VERA_ADDR_M
+                    lda  cx16.r0L
+                    sta  cx16.VERA_ADDR_L
+                    ldy  cx16.r2L           ; xbits
+                    lda  mask4c,y
+                    and  cx16.VERA_DATA0
+                    ora  color
+                    sta  cx16.VERA_DATA0
+                }}
             }
         }
     }
 
     sub position(uword @zp x, uword y) {
+        ubyte bank
         when active_mode {
-            0 -> {
+            1 -> {
+                ; lores monochrome
                 cx16.r0 = y*(320/8) + x/8
                 cx16.vaddr(0, cx16.r0, 0, 1)
             }
-            128 -> {
+            ; TODO modes 2,3
+            4 -> {
+                ; lores 256c
+                void addr_mul_24_for_lores_256c(y, x)      ; 24 bits result is in r0 and r1L (highest byte)
+                bank = lsb(cx16.r1)
+                cx16.vaddr(bank, cx16.r0, 0, 1)
+            }
+            5 -> {
+                ; highres monochrome
                 cx16.r0 = y*(640/8) + x/8
                 cx16.vaddr(0, cx16.r0, 0, 1)
             }
-            1 -> {
-                void addr_mul_320_add_24(y, x)      ; 24 bits result is in r0 and r1L
-                ubyte bank = lsb(cx16.r1)
+            6 -> {
+                ; highres 4c
+                void addr_mul_24_for_highres_4c(y, x)      ; 24 bits result is in r0 and r1L (highest byte)
+                bank = lsb(cx16.r1)
                 cx16.vaddr(bank, cx16.r0, 0, 1)
             }
         }
     }
 
+    sub position2(uword @zp x, uword y, ubyte also_port_1) {
+        position(x, y)
+        if also_port_1 {
+            when active_mode {
+                1, 5 -> cx16.vaddr(0, cx16.r0, 1, 1)
+                ; TODO modes 2, 3
+                4, 6 -> {
+                    ubyte bank = lsb(cx16.r1)
+                    cx16.vaddr(bank, cx16.r0, 1, 1)
+                }
+            }
+        }
+    }
+
     inline asmsub next_pixel(ubyte color @A) {
         ; -- sets the next pixel byte to the graphics chip.
         ;    for 8 bpp screens this will plot 1 pixel.
         ;    for 1 bpp screens it will plot 8 pixels at once (color = bit pattern).
+        ;    for 2 bpp screens it will plot 4 pixels at once (color = bit pattern).
         %asm {{
             sta  cx16.VERA_DATA0
         }}
@@ -550,6 +709,7 @@ _done
         ; -- sets the next bunch of pixels from a prepared array of bytes.
         ;    for 8 bpp screens this will plot 1 pixel per byte.
         ;    for 1 bpp screens it will plot 8 pixels at once (colors are the bit patterns per byte).
+        ;    for 2 bpp screens it will plot 4 pixels at once (colors are the bit patterns per byte).
         %asm {{
             phx
             sta  P8ZP_SCRATCH_W1
@@ -614,13 +774,13 @@ _done
     sub text(uword @zp x, uword y, ubyte color, uword sctextptr) {
         ; -- Write some text at the given pixel position. The text string must be in screencode encoding (not petscii!).
         ;    You must also have called text_charset() first to select and prepare the character set to use.
-        ;    NOTE: in monochrome (1bpp) screen modes, x position is currently constrained to mulitples of 8 !
+        ;    NOTE: in monochrome (1bpp) screen modes, x position is currently constrained to multiples of 8 !  TODO allow per-pixel horizontal positioning
         uword chardataptr
         when active_mode {
-            0, 128 -> {
-                ; 1-bitplane modes
+            1, 5 -> {
+                ; monochrome mode, either resolution
                 cx16.r2 = 40
-                if active_mode>=128
+                if active_mode==5
                     cx16.r2 = 80
                 while @(sctextptr) {
                     chardataptr = charset_addr + (@(sctextptr) as uword)*8
@@ -660,12 +820,13 @@ _done
                     sctextptr++
                 }
             }
-            1 -> {
-                ; 320 x 240 x 256c
+            4 -> {
+                ; lores 256c
                 while @(sctextptr) {
                     chardataptr = charset_addr + (@(sctextptr) as uword)*8
                     cx16.vaddr(charset_bank, chardataptr, 1, 1)
                     repeat 8 {
+                        ; TODO rewrite this inner loop fully in assembly
                         position(x,y)
                         y++
                         %asm {{
@@ -689,6 +850,28 @@ _done
                     sctextptr++
                 }
             }
+            6 -> {
+                ; hires 4c
+                while @(sctextptr) {
+                    chardataptr = charset_addr + (@(sctextptr) as uword)*8
+                    repeat 8 {
+                        ; TODO rewrite this inner loop fully in assembly
+                        ubyte charbits = cx16.vpeek(charset_bank, chardataptr)
+                        repeat 8 {
+                            charbits <<= 1
+                            if_cs
+                                plot(x, y, color)
+                            x++
+                        }
+                        x-=8
+                        chardataptr++
+                        y++
+                    }
+                    x+=8
+                    y-=8
+                    sctextptr++
+                }
+            }
         }
     }
 
@@ -709,48 +892,98 @@ _done
         }}
     }
 
-    asmsub addr_mul_320_add_24(uword address @R0, uword value @AY) clobbers(A) -> uword @R0, ubyte @R1  {
-            %asm {{
-                sta  P8ZP_SCRATCH_W1
-                sty  P8ZP_SCRATCH_W1+1
-                lda  cx16.r0
-                sta  P8ZP_SCRATCH_B1
-                lda  cx16.r0+1
-                sta  cx16.r1
-                sta  P8ZP_SCRATCH_REG
-                lda  cx16.r0
-                asl  a
-                rol  P8ZP_SCRATCH_REG
-                asl  a
-                rol  P8ZP_SCRATCH_REG
-                asl  a
-                rol  P8ZP_SCRATCH_REG
-                asl  a
-                rol  P8ZP_SCRATCH_REG
-                asl  a
-                rol  P8ZP_SCRATCH_REG
-                asl  a
-                rol  P8ZP_SCRATCH_REG
-                sta  cx16.r0
-                lda  P8ZP_SCRATCH_B1
-                clc
-                adc  P8ZP_SCRATCH_REG
-                sta  cx16.r0+1
-                bcc  +
-                inc  cx16.r1
-+		        ; now add the value to this 24-bits number
-                lda  cx16.r0
-                clc
-                adc  P8ZP_SCRATCH_W1
-                sta  cx16.r0
-                lda  cx16.r0+1
-                adc  P8ZP_SCRATCH_W1+1
-                sta  cx16.r0+1
-                bcc  +
-                inc  cx16.r1
-+               lda  cx16.r1
-                rts
-            }}
-        }
+    asmsub addr_mul_24_for_highres_4c(uword yy @R2, uword xx @R3)  clobbers(A, Y) -> uword @R0, uword @R1 {
+        ; yy * 160 + xx/4  (24 bits calculation)
+        ; 24 bits result is in r0 and r1L (highest byte)
+        %asm {{
+            ldy  #5
+-           asl  cx16.r2
+            rol  cx16.r2+1
+            dey
+            bne  -
+            lda  cx16.r2
+            sta  cx16.r0
+            lda  cx16.r2+1
+            sta  cx16.r0+1
+            asl  cx16.r0
+            rol  cx16.r0+1
+            asl  cx16.r0
+            rol  cx16.r0+1
+
+            ; xx >>= 2  (xx=R3)
+            lsr  cx16.r3+1
+            ror  cx16.r3
+            lsr  cx16.r3+1
+            ror  cx16.r3
+
+            ; add r2 and xx (r3) to r0 (24-bits)
+            stz  cx16.r1
+            clc
+            lda  cx16.r0
+            adc  cx16.r2
+            sta  cx16.r0
+            lda  cx16.r0+1
+            adc  cx16.r2+1
+            sta  cx16.r0+1
+            bcc  +
+            inc  cx16.r1
++           clc
+            lda  cx16.r0
+            adc  cx16.r3
+            sta  cx16.r0
+            lda  cx16.r0+1
+            adc  cx16.r3+1
+            sta  cx16.r0+1
+            bcc  +
+            inc  cx16.r1
++
+            rts
+        }}
+    }
+
+    asmsub addr_mul_24_for_lores_256c(uword yy @R0, uword xx @AY) clobbers(A) -> uword @R0, ubyte @R1  {
+        ; yy * 320 + xx (24 bits calculation)
+        %asm {{
+            sta  P8ZP_SCRATCH_W1
+            sty  P8ZP_SCRATCH_W1+1
+            lda  cx16.r0
+            sta  P8ZP_SCRATCH_B1
+            lda  cx16.r0+1
+            sta  cx16.r1
+            sta  P8ZP_SCRATCH_REG
+            lda  cx16.r0
+            asl  a
+            rol  P8ZP_SCRATCH_REG
+            asl  a
+            rol  P8ZP_SCRATCH_REG
+            asl  a
+            rol  P8ZP_SCRATCH_REG
+            asl  a
+            rol  P8ZP_SCRATCH_REG
+            asl  a
+            rol  P8ZP_SCRATCH_REG
+            asl  a
+            rol  P8ZP_SCRATCH_REG
+            sta  cx16.r0
+            lda  P8ZP_SCRATCH_B1
+            clc
+            adc  P8ZP_SCRATCH_REG
+            sta  cx16.r0+1
+            bcc  +
+            inc  cx16.r1
++           ; now add the value to this 24-bits number
+            lda  cx16.r0
+            clc
+            adc  P8ZP_SCRATCH_W1
+            sta  cx16.r0
+            lda  cx16.r0+1
+            adc  P8ZP_SCRATCH_W1+1
+            sta  cx16.r0+1
+            bcc  +
+            inc  cx16.r1
++           lda  cx16.r1
+            rts
+        }}
+    }
 
 }

compiler/res/prog8lib/cx16/graphics.p8

@@ -1,10 +1,9 @@
-%target cx16
 %import syslib
 %import textio
 
 ; Bitmap pixel graphics module for the CommanderX16
 ; wraps the graphics functions that are in ROM.
-; only black/white monchrome 320x200 for now. (i.e. truncated at the bottom)
+; only black/white monochrome 320x200 for now. (i.e. truncated at the bottom)
 ; For full-screen 640x480 or 320x240 graphics, use the "gfx2" module instead. (but that is Cx16-specific)
 ; Note: there is no color palette manipulation here, you have to do that yourself or use the "palette" module.
 

compiler/res/prog8lib/cx16/palette.p8

@@ -1,5 +1,3 @@
-%target cx16
-
 ; Manipulate the Commander X16's display color palette.
 ; Should you want to restore the default palette, you have to reinitialize the Vera yourself.
 
@@ -9,34 +7,46 @@ palette {
     ubyte c
 
     sub set_color(ubyte index, uword color) {
-        cx16.vpoke(1, $fa00+index*2, lsb(color))
-        cx16.vpoke(1, $fa01+index*2, msb(color))
+        vera_palette_ptr = $fa00+(index as uword * 2)
+        cx16.vpoke(1, vera_palette_ptr, lsb(color))
+        vera_palette_ptr++
+        cx16.vpoke(1, vera_palette_ptr, msb(color))
     }
 
-    sub set_rgb4(uword palletteptr, uword num_colors) {
+    sub set_rgb4(uword palette_bytes_ptr, uword num_colors) {
         ; 2 bytes per color entry, the Vera uses this, but the R/GB bytes order is swapped
         vera_palette_ptr = $fa00
         repeat num_colors {
-            cx16.vpoke(1, vera_palette_ptr+1, @(palletteptr))
-            palletteptr++
-            cx16.vpoke(1, vera_palette_ptr, @(palletteptr))
-            palletteptr++
+            cx16.vpoke(1, vera_palette_ptr+1, @(palette_bytes_ptr))
+            palette_bytes_ptr++
+            cx16.vpoke(1, vera_palette_ptr, @(palette_bytes_ptr))
+            palette_bytes_ptr++
             vera_palette_ptr+=2
         }
     }
 
-    sub set_rgb8(uword palletteptr, uword num_colors) {
+    sub set_rgb(uword palette_words_ptr, uword num_colors) {
+        ; 1 word per color entry (in little endian format so $gb0r)
+        vera_palette_ptr = $fa00
+        repeat num_colors*2 {
+            cx16.vpoke(1, vera_palette_ptr, @(palette_words_ptr))
+            palette_words_ptr++
+            vera_palette_ptr++
+        }
+    }
+
+    sub set_rgb8(uword palette_bytes_ptr, uword num_colors) {
         ; 3 bytes per color entry, adjust color depth from 8 to 4 bits per channel.
         vera_palette_ptr = $fa00
         ubyte red
         ubyte greenblue
         repeat num_colors {
-            red = @(palletteptr) >> 4
-            palletteptr++
-            greenblue = @(palletteptr) & %11110000
-            palletteptr++
-            greenblue |= @(palletteptr) >> 4    ; add Blue
-            palletteptr++
+            red = @(palette_bytes_ptr) >> 4
+            palette_bytes_ptr++
+            greenblue = @(palette_bytes_ptr) & %11110000
+            palette_bytes_ptr++
+            greenblue |= @(palette_bytes_ptr) >> 4    ; add Blue
+            palette_bytes_ptr++
             cx16.vpoke(1, vera_palette_ptr, greenblue)
             vera_palette_ptr++
             cx16.vpoke(1, vera_palette_ptr, red)
@@ -44,20 +54,28 @@ palette {
         }
     }
 
-    sub set_monochrome() {
+    sub set_monochrome(uword screencolorRGB, uword drawcolorRGB) {
         vera_palette_ptr = $fa00
-        cx16.vpoke(1, vera_palette_ptr, 0)
+        cx16.vpoke(1, vera_palette_ptr, lsb(screencolorRGB))   ; G,B
         vera_palette_ptr++
-        cx16.vpoke(1, vera_palette_ptr, 0)
+        cx16.vpoke(1, vera_palette_ptr, msb(screencolorRGB))   ; R
         vera_palette_ptr++
         repeat 255 {
-            cx16.vpoke(1, vera_palette_ptr, 255)
+            cx16.vpoke(1, vera_palette_ptr, lsb(drawcolorRGB)) ; G,B
             vera_palette_ptr++
-            cx16.vpoke(1, vera_palette_ptr, 255)
+            cx16.vpoke(1, vera_palette_ptr, msb(drawcolorRGB)) ; R
             vera_palette_ptr++
         }
     }
 
+    sub set_all_black() {
+        set_monochrome($000, $000)
+    }
+
+    sub set_all_white() {
+        set_monochrome($fff, $fff)
+    }
+
     sub set_grayscale() {
         vera_palette_ptr = $fa00
         repeat 16 {
@@ -88,7 +106,7 @@ palette {
         $666,  ; 12 = medium grey
         $9D8,  ; 13 = light green
         $65B,  ; 14 = light blue
-        $999  ; 15 = light grey
+        $999   ; 15 = light grey
     ]
 
     uword[] C64_colorpalette_pepto = [  ; # this is Pepto's Commodore-64 palette  http://www.pepto.de/projects/colorvic/
@@ -107,7 +125,7 @@ palette {
         $777,  ; 12 = medium grey
         $af9,  ; 13 = light green
         $76e,  ; 14 = light blue
-        $bbb  ; 15 = light grey
+        $bbb   ; 15 = light grey
     ]
 
     uword[] C64_colorpalette_light = [  ; this is a lighter palette

compiler/res/prog8lib/cx16/syslib.p8

@@ -5,9 +5,6 @@
 ;
 ; indent format: TABS, size=8
 
-%target cx16
-
-
 c64 {
 
 ; ---- kernal routines, these are the same as on the Commodore-64 (hence the same block name) ----
@@ -24,7 +21,7 @@ romsub $FF8D = VECTOR(uword userptr @ XY, ubyte dir @ Pc) clobbers(A,Y)     ; re
 romsub $FF90 = SETMSG(ubyte value @ A)                          ; set Kernal message control flag
 romsub $FF93 = SECOND(ubyte address @ A) clobbers(A)            ; (alias: LSTNSA) send secondary address after LISTEN
 romsub $FF96 = TKSA(ubyte address @ A) clobbers(A)              ; (alias: TALKSA) send secondary address after TALK
-romsub $FF99 = MEMTOP(uword address @ XY, ubyte dir @ Pc) -> uword @ XY     ; read/set top of memory  pointer.   NOTE: as a Cx16 extension, also returns the number of RAM memory banks in register A !  See MEMTOP2
+romsub $FF99 = MEMTOP(uword address @ XY, ubyte dir @ Pc) -> uword @ XY     ; read/set top of memory  pointer.   NOTE: as a Cx16 extension, also returns the number of RAM memory banks in register A !  See cx16.numbanks()
 romsub $FF9C = MEMBOT(uword address @ XY, ubyte dir @ Pc) -> uword @ XY     ; read/set bottom of memory  pointer
 romsub $FF9F = SCNKEY() clobbers(A,X,Y)                         ; scan the keyboard
 romsub $FFA2 = SETTMO(ubyte timeout @ A)                        ; set time-out flag for IEEE bus
@@ -35,7 +32,7 @@ romsub $FFAE = UNLSN() clobbers(A)                              ; command serial
 romsub $FFB1 = LISTEN(ubyte device @ A) clobbers(A)             ; command serial bus device to LISTEN
 romsub $FFB4 = TALK(ubyte device @ A) clobbers(A)               ; command serial bus device to TALK
 romsub $FFB7 = READST() -> ubyte @ A                            ; read I/O status word
-romsub $FFBA = SETLFS(ubyte logical @ A, ubyte device @ X, ubyte address @ Y)   ; set logical file parameters
+romsub $FFBA = SETLFS(ubyte logical @ A, ubyte device @ X, ubyte secondary @ Y)   ; set logical file parameters
 romsub $FFBD = SETNAM(ubyte namelen @ A, str filename @ XY)     ; set filename parameters
 romsub $FFC0 = OPEN() clobbers(X,Y) -> ubyte @Pc, ubyte @A      ; (via 794 ($31A)) open a logical file
 romsub $FFC3 = CLOSE(ubyte logical @ A) clobbers(A,X,Y)         ; (via 796 ($31C)) close a logical file
@@ -44,10 +41,10 @@ romsub $FFC9 = CHKOUT(ubyte logical @ X) clobbers(A,X)          ; (via 800 ($320
 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 $FFD5 = LOAD(ubyte verify @ A, uword address @ XY) -> ubyte @Pc, ubyte @ A, ubyte @ X, ubyte @ Y     ; (via 816 ($330)) load from device
-romsub $FFD8 = SAVE(ubyte zp_startaddr @ A, uword endaddr @ XY) -> ubyte @ Pc, ubyte @ A                    ; (via 818 ($332)) save to a device
+romsub $FFD5 = LOAD(ubyte verify @ A, uword address @ XY) -> ubyte @Pc, ubyte @ A, uword @ XY     ; (via 816 ($330)) load from device
+romsub $FFD8 = SAVE(ubyte zp_startaddr @ A, uword endaddr @ XY) -> ubyte @ Pc, ubyte @ A          ; (via 818 ($332)) save to a device
 romsub $FFDB = SETTIM(ubyte low @ A, ubyte middle @ X, ubyte high @ Y)      ; set the software clock
-romsub $FFDE = RDTIM() -> ubyte @ A, ubyte @ X, ubyte @ Y       ; read the software clock
+romsub $FFDE = RDTIM() -> ubyte @ A, ubyte @ X, ubyte @ Y       ; read the software clock (A=lo,X=mid,Y=high)
 romsub $FFE1 = STOP() clobbers(X) -> ubyte @ Pz, ubyte @ A      ; (via 808 ($328)) check the STOP key (and some others in A)
 romsub $FFE4 = GETIN() clobbers(X,Y) -> ubyte @Pc, ubyte @ A    ; (via 810 ($32A)) get a character
 romsub $FFE7 = CLALL() clobbers(A,X)                            ; (via 812 ($32C)) close all files
@@ -74,7 +71,7 @@ asmsub STOP2() -> ubyte @A  {
 }
 
 asmsub RDTIM16() -> uword @AY {
-    ; --  like RDTIM() but only returning the lower 16 bits for convenience
+    ; --  like RDTIM() but only returning the lower 16 bits in AY for convenience
     %asm {{
         phx
         jsr  c64.RDTIM
@@ -87,25 +84,15 @@ asmsub RDTIM16() -> uword @AY {
     }}
 }
 
-asmsub MEMTOP2() -> ubyte @A {
-    ; -- uses MEMTOP's cx16 extension to query the number of available RAM banks.
-    %asm {{
-        phx
-        sec
-        jsr  c64.MEMTOP
-        plx
-        rts
-    }}
-}
-
 }
 
 cx16 {
 
-; 65c02 hardware vectors:
-    &uword  NMI_VEC         = $FFFA     ; 6502 nmi vector, determined by the kernal if banked in
-    &uword  RESET_VEC       = $FFFC     ; 6502 reset vector, determined by the kernal if banked in
-    &uword  IRQ_VEC         = $FFFE     ; 6502 interrupt vector, determined by the kernal if banked in
+; irq and hardware vectors:
+    &uword  CINV            = $0314     ; IRQ vector (in ram)
+    &uword  NMI_VEC         = $FFFA     ; 65c02 nmi vector, determined by the kernal if banked in
+    &uword  RESET_VEC       = $FFFC     ; 65c02 reset vector, determined by the kernal if banked in
+    &uword  IRQ_VEC         = $FFFE     ; 65c02 interrupt vector, determined by the kernal if banked in
 
 
 ; the sixteen virtual 16-bit registers
@@ -126,52 +113,87 @@ cx16 {
     &uword r14 = $001e
     &uword r15 = $0020
 
+    &ubyte r0L  = $0002
+    &ubyte r1L  = $0004
+    &ubyte r2L  = $0006
+    &ubyte r3L  = $0008
+    &ubyte r4L  = $000a
+    &ubyte r5L  = $000c
+    &ubyte r6L  = $000e
+    &ubyte r7L  = $0010
+    &ubyte r8L  = $0012
+    &ubyte r9L  = $0014
+    &ubyte r10L = $0016
+    &ubyte r11L = $0018
+    &ubyte r12L = $001a
+    &ubyte r13L = $001c
+    &ubyte r14L = $001e
+    &ubyte r15L = $0020
+
+    &ubyte r0H  = $0003
+    &ubyte r1H  = $0005
+    &ubyte r2H  = $0007
+    &ubyte r3H  = $0009
+    &ubyte r4H  = $000b
+    &ubyte r5H  = $000d
+    &ubyte r6H  = $000f
+    &ubyte r7H  = $0011
+    &ubyte r8H  = $0013
+    &ubyte r9H  = $0015
+    &ubyte r10H = $0017
+    &ubyte r11H = $0019
+    &ubyte r12H = $001b
+    &ubyte r13H = $001d
+    &ubyte r14H = $001f
+    &ubyte r15H = $0021
+
+
 ; VERA registers
 
-    const uword VERA_BASE = $9F20
-    &ubyte  VERA_ADDR_L   	  = VERA_BASE + $0000
-    &ubyte  VERA_ADDR_M   	  = VERA_BASE + $0001
-    &ubyte  VERA_ADDR_H   	  = VERA_BASE + $0002
-    &ubyte  VERA_DATA0        = VERA_BASE + $0003
-    &ubyte  VERA_DATA1        = VERA_BASE + $0004
-    &ubyte  VERA_CTRL         = VERA_BASE + $0005
-    &ubyte  VERA_IEN          = VERA_BASE + $0006
-    &ubyte  VERA_ISR          = VERA_BASE + $0007
-    &ubyte  VERA_IRQ_LINE_L   = VERA_BASE + $0008
-    &ubyte  VERA_DC_VIDEO     = VERA_BASE + $0009
-    &ubyte  VERA_DC_HSCALE    = VERA_BASE + $000A
-    &ubyte  VERA_DC_VSCALE    = VERA_BASE + $000B
-    &ubyte  VERA_DC_BORDER    = VERA_BASE + $000C
-    &ubyte  VERA_DC_HSTART    = VERA_BASE + $0009
-    &ubyte  VERA_DC_HSTOP     = VERA_BASE + $000A
-    &ubyte  VERA_DC_VSTART    = VERA_BASE + $000B
-    &ubyte  VERA_DC_VSTOP     = VERA_BASE + $000C
-    &ubyte  VERA_L0_CONFIG    = VERA_BASE + $000D
-    &ubyte  VERA_L0_MAPBASE   = VERA_BASE + $000E
-    &ubyte  VERA_L0_TILEBASE  = VERA_BASE + $000F
-    &ubyte  VERA_L0_HSCROLL_L = VERA_BASE + $0010
-    &ubyte  VERA_L0_HSCROLL_H = VERA_BASE + $0011
-    &ubyte  VERA_L0_VSCROLL_L = VERA_BASE + $0012
-    &ubyte  VERA_L0_VSCROLL_H = VERA_BASE + $0013
-    &ubyte  VERA_L1_CONFIG    = VERA_BASE + $0014
-    &ubyte  VERA_L1_MAPBASE   = VERA_BASE + $0015
-    &ubyte  VERA_L1_TILEBASE  = VERA_BASE + $0016
-    &ubyte  VERA_L1_HSCROLL_L = VERA_BASE + $0017
-    &ubyte  VERA_L1_HSCROLL_H = VERA_BASE + $0018
-    &ubyte  VERA_L1_VSCROLL_L = VERA_BASE + $0019
-    &ubyte  VERA_L1_VSCROLL_H = VERA_BASE + $001A
-    &ubyte  VERA_AUDIO_CTRL   = VERA_BASE + $001B
-    &ubyte  VERA_AUDIO_RATE   = VERA_BASE + $001C
-    &ubyte  VERA_AUDIO_DATA   = VERA_BASE + $001D
-    &ubyte  VERA_SPI_DATA     = VERA_BASE + $001E
-    &ubyte  VERA_SPI_CTRL     = VERA_BASE + $001F
+    const uword VERA_BASE       = $9F20
+    &ubyte  VERA_ADDR_L         = VERA_BASE + $0000
+    &ubyte  VERA_ADDR_M         = VERA_BASE + $0001
+    &ubyte  VERA_ADDR_H         = VERA_BASE + $0002
+    &ubyte  VERA_DATA0          = VERA_BASE + $0003
+    &ubyte  VERA_DATA1          = VERA_BASE + $0004
+    &ubyte  VERA_CTRL           = VERA_BASE + $0005
+    &ubyte  VERA_IEN            = VERA_BASE + $0006
+    &ubyte  VERA_ISR            = VERA_BASE + $0007
+    &ubyte  VERA_IRQ_LINE_L     = VERA_BASE + $0008
+    &ubyte  VERA_DC_VIDEO       = VERA_BASE + $0009
+    &ubyte  VERA_DC_HSCALE      = VERA_BASE + $000A
+    &ubyte  VERA_DC_VSCALE      = VERA_BASE + $000B
+    &ubyte  VERA_DC_BORDER      = VERA_BASE + $000C
+    &ubyte  VERA_DC_HSTART      = VERA_BASE + $0009
+    &ubyte  VERA_DC_HSTOP       = VERA_BASE + $000A
+    &ubyte  VERA_DC_VSTART      = VERA_BASE + $000B
+    &ubyte  VERA_DC_VSTOP       = VERA_BASE + $000C
+    &ubyte  VERA_L0_CONFIG      = VERA_BASE + $000D
+    &ubyte  VERA_L0_MAPBASE     = VERA_BASE + $000E
+    &ubyte  VERA_L0_TILEBASE    = VERA_BASE + $000F
+    &ubyte  VERA_L0_HSCROLL_L   = VERA_BASE + $0010
+    &ubyte  VERA_L0_HSCROLL_H   = VERA_BASE + $0011
+    &ubyte  VERA_L0_VSCROLL_L   = VERA_BASE + $0012
+    &ubyte  VERA_L0_VSCROLL_H   = VERA_BASE + $0013
+    &ubyte  VERA_L1_CONFIG      = VERA_BASE + $0014
+    &ubyte  VERA_L1_MAPBASE     = VERA_BASE + $0015
+    &ubyte  VERA_L1_TILEBASE    = VERA_BASE + $0016
+    &ubyte  VERA_L1_HSCROLL_L   = VERA_BASE + $0017
+    &ubyte  VERA_L1_HSCROLL_H   = VERA_BASE + $0018
+    &ubyte  VERA_L1_VSCROLL_L   = VERA_BASE + $0019
+    &ubyte  VERA_L1_VSCROLL_H   = VERA_BASE + $001A
+    &ubyte  VERA_AUDIO_CTRL     = VERA_BASE + $001B
+    &ubyte  VERA_AUDIO_RATE     = VERA_BASE + $001C
+    &ubyte  VERA_AUDIO_DATA     = VERA_BASE + $001D
+    &ubyte  VERA_SPI_DATA       = VERA_BASE + $001E
+    &ubyte  VERA_SPI_CTRL       = VERA_BASE + $001F
 ; VERA_PSG_BASE     = $1F9C0
 ; VERA_PALETTE_BASE = $1FA00
 ; VERA_SPRITES_BASE = $1FC00
 
 ; I/O
 
-    const uword  via1  = $9f60                  ;VIA 6522 #1
+    const uword  via1   = $9f00                  ;VIA 6522 #1
     &ubyte  d1prb	= via1+0
     &ubyte  d1pra	= via1+1
     &ubyte  d1ddrb	= via1+2
@@ -189,7 +211,7 @@ cx16 {
     &ubyte  d1ier	= via1+14
     &ubyte  d1ora	= via1+15
 
-    const uword  via2  = $9f70                  ;VIA 6522 #2
+    const uword  via2   = $9f10                  ;VIA 6522 #2
     &ubyte  d2prb	= via2+0
     &ubyte  d2pra	= via2+1
     &ubyte  d2ddrb	= via2+2
@@ -207,6 +229,11 @@ cx16 {
     &ubyte  d2ier	= via2+14
     &ubyte  d2ora	= via2+15
 
+    &ubyte  ym2151adr	= $9f40
+    &ubyte  ym2151dat	= $9f41
+
+    const uword  extdev	= $9f60
+
 
 ; ---- Commander X-16 additions on top of C64 kernal routines ----
 ; spelling of the names is taken from the Commander X-16 rom sources
@@ -289,6 +316,32 @@ romsub $fecc = monitor()  clobbers(A,X,Y)
 
 
 ; ---- utilities -----
+
+inline asmsub rombank(ubyte rombank @A) {
+    ; -- set the rom banks
+    %asm {{
+        sta  $01            ; rom bank register (v39+, used to be cx16.d1prb $9f60 in v38)
+    }}
+}
+
+inline asmsub rambank(ubyte rambank @A) {
+    ; -- set the ram bank
+    %asm {{
+        sta  $00            ; ram bank register (v39+, used to be cx16.d1pra $9f61 in v38)
+    }}
+}
+
+asmsub numbanks() -> ubyte @A {
+    ; -- uses MEMTOP's cx16 extension to query the number of available RAM banks. (each is 8 Kb)
+    %asm {{
+        phx
+        sec
+        jsr  c64.MEMTOP
+        plx
+        rts
+    }}
+}
+
 asmsub vpeek(ubyte bank @A, uword address @XY) -> ubyte @A {
         ; -- get a byte from VERA's video memory
         ;    note: inefficient when reading multiple sequential bytes!
@@ -332,75 +385,126 @@ asmsub vaddr(ubyte bank @A, uword address @R0, ubyte addrsel @R1, byte autoIncrO
 }
 
 asmsub vpoke(ubyte bank @A, uword address @R0, ubyte value @Y) clobbers(A) {
-        ; -- write a single byte to VERA's video memory
-        ;    note: inefficient when writing multiple sequential bytes!
-        %asm {{
-            stz  cx16.VERA_CTRL
-            and  #1
-            sta  cx16.VERA_ADDR_H
-            lda  cx16.r0
-            sta  cx16.VERA_ADDR_L
-            lda  cx16.r0+1
-            sta  cx16.VERA_ADDR_M
-            sty  cx16.VERA_DATA0
-            rts
-        }}
+    ; -- write a single byte to VERA's video memory
+    ;    note: inefficient when writing multiple sequential bytes!
+    %asm {{
+        stz  cx16.VERA_CTRL
+        and  #1
+        sta  cx16.VERA_ADDR_H
+        lda  cx16.r0
+        sta  cx16.VERA_ADDR_L
+        lda  cx16.r0+1
+        sta  cx16.VERA_ADDR_M
+        sty  cx16.VERA_DATA0
+        rts
+    }}
 }
 
 asmsub vpoke_or(ubyte bank @A, uword address @R0, ubyte value @Y) clobbers (A) {
-        ; -- or a single byte to the value already in the VERA's video memory at that location
-        ;    note: inefficient when writing multiple sequential bytes!
-        %asm {{
-            stz  cx16.VERA_CTRL
-            and  #1
-            sta  cx16.VERA_ADDR_H
-            lda  cx16.r0
-            sta  cx16.VERA_ADDR_L
-            lda  cx16.r0+1
-            sta  cx16.VERA_ADDR_M
-            tya
-            ora  cx16.VERA_DATA0
-            sta  cx16.VERA_DATA0
-            rts
-        }}
+    ; -- or a single byte to the value already in the VERA's video memory at that location
+    ;    note: inefficient when writing multiple sequential bytes!
+    %asm {{
+        stz  cx16.VERA_CTRL
+        and  #1
+        sta  cx16.VERA_ADDR_H
+        lda  cx16.r0
+        sta  cx16.VERA_ADDR_L
+        lda  cx16.r0+1
+        sta  cx16.VERA_ADDR_M
+        tya
+        ora  cx16.VERA_DATA0
+        sta  cx16.VERA_DATA0
+        rts
+    }}
 }
 
 asmsub vpoke_and(ubyte bank @A, uword address @R0, ubyte value @Y) clobbers(A) {
-        ; -- and a single byte to the value already in the VERA's video memory at that location
-        ;    note: inefficient when writing multiple sequential bytes!
-        %asm {{
-            stz  cx16.VERA_CTRL
-            and  #1
-            sta  cx16.VERA_ADDR_H
-            lda  cx16.r0
-            sta  cx16.VERA_ADDR_L
-            lda  cx16.r0+1
-            sta  cx16.VERA_ADDR_M
-            tya
-            and  cx16.VERA_DATA0
-            sta  cx16.VERA_DATA0
-            rts
-        }}
+    ; -- and a single byte to the value already in the VERA's video memory at that location
+    ;    note: inefficient when writing multiple sequential bytes!
+    %asm {{
+        stz  cx16.VERA_CTRL
+        and  #1
+        sta  cx16.VERA_ADDR_H
+        lda  cx16.r0
+        sta  cx16.VERA_ADDR_L
+        lda  cx16.r0+1
+        sta  cx16.VERA_ADDR_M
+        tya
+        and  cx16.VERA_DATA0
+        sta  cx16.VERA_DATA0
+        rts
+    }}
 }
 
 asmsub vpoke_xor(ubyte bank @A, uword address @R0, ubyte value @Y) clobbers (A) {
-        ; -- xor a single byte to the value already in the VERA's video memory at that location
-        ;    note: inefficient when writing multiple sequential bytes!
-        %asm {{
-            stz  cx16.VERA_CTRL
-            and  #1
-            sta  cx16.VERA_ADDR_H
-            lda  cx16.r0
-            sta  cx16.VERA_ADDR_L
-            lda  cx16.r0+1
-            sta  cx16.VERA_ADDR_M
-            tya
-            eor  cx16.VERA_DATA0
-            sta  cx16.VERA_DATA0
-            rts
-        }}
+    ; -- xor a single byte to the value already in the VERA's video memory at that location
+    ;    note: inefficient when writing multiple sequential bytes!
+    %asm {{
+        stz  cx16.VERA_CTRL
+        and  #1
+        sta  cx16.VERA_ADDR_H
+        lda  cx16.r0
+        sta  cx16.VERA_ADDR_L
+        lda  cx16.r0+1
+        sta  cx16.VERA_ADDR_M
+        tya
+        eor  cx16.VERA_DATA0
+        sta  cx16.VERA_DATA0
+        rts
+    }}
 }
 
+asmsub vload(str name @R0, ubyte device @Y, ubyte bank @A, uword address @R1) -> ubyte @A {
+    ; -- like the basic command VLOAD "filename",device,bank,address
+    ;    loads a file into video memory in the given bank:address, returns success in A
+    ;    !! NOTE !! the V38 ROMs contain a bug in the LOAD code that makes the load address not work correctly,
+    ;               it works fine when loading from local filesystem
+    %asm {{
+        ; -- load a file into video ram
+        phx
+        pha
+        tya
+        tax
+        lda  #1
+        ldy  #0
+        jsr  c64.SETLFS
+        lda  cx16.r0
+        ldy  cx16.r0+1
+        jsr  prog8_lib.strlen
+        tya
+        ldx  cx16.r0
+        ldy  cx16.r0+1
+        jsr  c64.SETNAM
+        pla
+        clc
+        adc  #2
+        ldx  cx16.r1
+        ldy  cx16.r1+1
+        stz  P8ZP_SCRATCH_B1
+        jsr  c64.LOAD
+        bcs  +
+        inc  P8ZP_SCRATCH_B1
++       jsr  c64.CLRCHN
+        lda  #1
+        jsr  c64.CLOSE
+        plx
+        lda  P8ZP_SCRATCH_B1
+        rts
+    }}
+}
+
+inline asmsub joystick_get2(ubyte joynr @A) clobbers(Y) -> uword @AX  {
+    ; convenience routine to get the joystick state without requiring inline assembly that deals with the multiple return values.
+    ; Also disables interrupts to avoid the IRQ race condition mentioned here: https://github.com/commanderx16/x16-rom/issues/203
+    ; TODO once that issue is resolved, this routine can be redefined as:  romsub $ff56 = joystick_get2(ubyte joynr @A) clobbers(Y) -> uword @AX
+    %asm {{
+        sei
+        jsr  cx16.joystick_get
+        cli
+    }}
+}
+
+
 sub FB_set_pixels_from_buf(uword buffer, uword count) {
     %asm {{
             ; -- This is replacement code for the normal FB_set_pixels subroutine in ROM
@@ -436,17 +540,15 @@ _loop       ldy  #0
 }
 
 ; ---- system stuff -----
-asmsub init_system()  {
+asmsub  init_system()  {
     ; Initializes the machine to a sane starting state.
     ; Called automatically by the loader program logic.
     %asm {{
         sei
         cld
-        ;stz  $00
-        ;stz  $01
-        ;stz  d1prb      ; select rom bank 0
         lda  #$80
         sta  VERA_CTRL
+        stz  $01        ; select rom bank 0 (enable kernal)
         jsr  c64.IOINIT
         jsr  c64.RESTOR
         jsr  c64.CINT
@@ -468,8 +570,177 @@ asmsub init_system()  {
     }}
 }
 
+asmsub  init_system_phase2()  {
+    %asm {{
+        sei
+        lda  cx16.CINV
+        sta  restore_irq._orig_irqvec
+        lda  cx16.CINV+1
+        sta  restore_irq._orig_irqvec+1
+        cli
+        rts
+    }}
 }
 
+asmsub  set_irq(uword handler @AY, ubyte useKernal @Pc) clobbers(A)  {
+	%asm {{
+	        sta  _modified+1
+	        sty  _modified+2
+	        lda  #0
+	        adc  #0
+	        sta  _use_kernal
+		sei
+		lda  #<_irq_handler
+		sta  cx16.CINV
+		lda  #>_irq_handler
+		sta  cx16.CINV+1
+                lda  cx16.VERA_IEN
+                ora  #%00000001     ; enable the vsync irq
+                sta  cx16.VERA_IEN
+		cli
+		rts
+
+_irq_handler    jsr  _irq_handler_init
+_modified	jsr  $ffff                      ; modified
+		jsr  _irq_handler_end
+		lda  _use_kernal
+		bne  +
+		; end irq processing - don't use kernal's irq handling
+		lda  cx16.VERA_ISR
+		ora  #1
+		sta  cx16.VERA_ISR      ; clear Vera Vsync irq status
+		ply
+		plx
+		pla
+		rti
++		jmp  (restore_irq._orig_irqvec)   ; continue with normal kernal irq routine
+
+_use_kernal     .byte  0
+
+_irq_handler_init
+		; save all zp scratch registers and the X register as these might be clobbered by the irq routine
+		stx  IRQ_X_REG
+		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
+		; stack protector; make sure we don't clobber the top of the evaluation stack
+		dex
+		dex
+		dex
+		dex
+		dex
+		dex
+		cld
+		rts
+
+_irq_handler_end
+		; restore all zp scratch registers and the X register
+		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
+		ldx  IRQ_X_REG
+		rts
+
+IRQ_X_REG		.byte  0
+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) {
+	%asm {{
+	    sei
+	    lda  _orig_irqvec
+	    sta  cx16.CINV
+	    lda  _orig_irqvec+1
+	    sta  cx16.CINV+1
+	    lda  cx16.VERA_IEN
+	    and  #%11110000     ; disable all Vera IRQs
+	    ora  #%00000001     ; enable only the vsync Irq
+	    sta  cx16.VERA_IEN
+	    cli
+	    rts
+_orig_irqvec    .word  0
+        }}
+}
+
+asmsub  set_rasterirq(uword handler @AY, uword rasterpos @R0) clobbers(A) {
+	%asm {{
+            sta  _modified+1
+            sty  _modified+2
+            lda  cx16.r0
+            ldy  cx16.r0+1
+            sei
+            lda  cx16.VERA_IEN
+            and  #%11110000     ; clear other IRQs
+            ora  #%00000010     ; enable the line (raster) irq
+            sta  cx16.VERA_IEN
+            lda  cx16.r0
+            ldy  cx16.r0+1
+            jsr  set_rasterline
+            lda  #<_raster_irq_handler
+            sta  cx16.CINV
+            lda  #>_raster_irq_handler
+            sta  cx16.CINV+1
+            cli
+            rts
+
+_raster_irq_handler
+            jsr  set_irq._irq_handler_init
+_modified   jsr  $ffff                      ; modified
+            jsr  set_irq._irq_handler_end
+            ; end irq processing - don't use kernal's irq handling
+            lda  cx16.VERA_ISR
+            ora  #%00000010
+            sta  cx16.VERA_ISR      ; clear Vera line irq status
+            ply
+            plx
+            pla
+            rti
+        }}
+}
+
+asmsub  set_rasterline(uword line @AY) {
+    %asm {{
+        sta  cx16.VERA_IRQ_LINE_L
+        lda  cx16.VERA_IEN
+        and  #%01111111
+        sta  cx16.VERA_IEN
+        tya
+        lsr  a
+        ror  a
+        and  #%10000000
+        ora  cx16.VERA_IEN
+        sta  cx16.VERA_IEN
+        rts
+    }}
+}
+
+}
+
+
 sys {
     ; ------- lowlevel system routines --------
 
@@ -477,24 +748,37 @@ sys {
 
 
     asmsub reset_system() {
-        ; Soft-reset the system back to Basic prompt.
+        ; Soft-reset the system back to initial power-on Basic prompt.
         %asm {{
             sei
-            lda  #14
-            sta  $01
-            stz  cx16.d1prb         ; bank the kernal in
+            stz  $01            ; bank the kernal in
             jmp  (cx16.RESET_VEC)
         }}
     }
 
-    sub wait(uword jiffies) {
-        ; --- wait approximately the given number of jiffies (1/60th seconds)
-        repeat jiffies {
-            ubyte jiff = lsb(c64.RDTIM16())
-            while jiff==lsb(c64.RDTIM16()) {
-                ; wait until 1 jiffy has passed
-            }
-        }
+    asmsub wait(uword jiffies @AY) {
+        ; --- wait approximately the given number of jiffies (1/60th seconds) (N or N+1)
+        ;     note: regular system vsync irq handler must be running, and no nother irqs
+        %asm {{
+-           wai             ; wait for irq (assume it was vsync)
+            cmp  #0
+            bne  +
+            dey
++           dec  a
+            bne  -
+            cpy  #0
+            bne  -
+            rts
+        }}
+    }
+
+    inline asmsub waitvsync()  {
+        ; --- suspend execution until the next vsync has occurred, without depending on custom irq handling.
+        ;     note: system vsync irq handler has to be active for this routine to work (and no other irqs-- which is the default).
+        ;     note: a more accurate way to wait for vsync is to set up a vsync irq handler instead.
+        %asm {{
+            wai
+        }}
     }
 
     inline asmsub memcopy(uword source @R0, uword target @R1, uword count @AY) clobbers(A,X,Y) {

compiler/res/prog8lib/cx16/textio.p8

@@ -4,7 +4,6 @@
 ;
 ; indent format: TABS, size=8
 
-%target cx16
 %import syslib
 %import conv
 
@@ -19,12 +18,27 @@ sub clear_screen() {
     txt.chrout(147)
 }
 
+sub home() {
+    txt.chrout(19)
+}
+
 sub nl() {
     txt.chrout('\n')
 }
 
-sub home() {
-    txt.chrout(19)
+sub spc() {
+    txt.chrout(' ')
+}
+
+asmsub column(ubyte col @A) clobbers(A, X, Y) {
+    ; ---- set the cursor on the given column (starting with 0) on the current line
+    %asm {{
+        sec
+        jsr  c64.PLOT
+        tay
+        clc
+        jmp  c64.PLOT
+    }}
 }
 
 asmsub  fill_screen (ubyte char @ A, ubyte color @ Y) clobbers(A)  {
@@ -405,7 +419,7 @@ _print_byte_digits
 		jsr  c64.CHROUT
 		pla
 		jsr  c64.CHROUT
-		jmp  _ones
+		bra  _ones
 +       pla
         cmp  #'0'
         beq  _ones
@@ -428,7 +442,7 @@ asmsub  print_b  (byte value @ A) clobbers(A,Y)  {
 		jsr  c64.CHROUT
 +		pla
 		jsr  conv.byte2decimal
-		jmp  print_ub._print_byte_digits
+		bra  print_ub._print_byte_digits
 	}}
 }
 
@@ -479,7 +493,7 @@ asmsub  print_uwbin  (uword value @ AY, ubyte prefix @ Pc) clobbers(A,Y)  {
 		jsr  print_ubbin
 		pla
 		clc
-		jmp  print_ubbin
+		bra  print_ubbin
 	}}
 }
 
@@ -492,7 +506,7 @@ asmsub  print_uwhex  (uword value @ AY, ubyte prefix @ Pc) clobbers(A,Y)  {
 		jsr  print_ubhex
 		pla
 		clc
-		jmp  print_ubhex
+		bra  print_ubhex
 	}}
 }
 
@@ -555,7 +569,7 @@ asmsub  print_w  (word value @ AY) clobbers(A,Y)  {
 		adc  #1
 		bcc  +
 		iny
-+		jmp  print_uw
++		bra  print_uw
 	}}
 }
 
@@ -583,95 +597,126 @@ asmsub  input_chars  (uword buffer @ AY) clobbers(A) -> ubyte @ Y  {
 asmsub  setchr  (ubyte col @X, ubyte row @Y, ubyte character @A) clobbers(A)  {
 	; ---- sets the character in the screen matrix at the given position
 	%asm {{
-		pha
-		txa
-		asl  a
-        stz  cx16.VERA_CTRL
-		stz  cx16.VERA_ADDR_H
-		sta  cx16.VERA_ADDR_L
-		sty  cx16.VERA_ADDR_M
-		pla
-        sta  cx16.VERA_DATA0
-		rts
+            pha
+            txa
+            asl  a
+            stz  cx16.VERA_CTRL
+            stz  cx16.VERA_ADDR_H
+            sta  cx16.VERA_ADDR_L
+            sty  cx16.VERA_ADDR_M
+            pla
+            sta  cx16.VERA_DATA0
+            rts
 	}}
 }
 
 asmsub  getchr  (ubyte col @A, ubyte row @Y) -> ubyte @ A {
 	; ---- get the character in the screen matrix at the given location
 	%asm  {{
-		asl  a
-        stz  cx16.VERA_CTRL
-		stz  cx16.VERA_ADDR_H
-		sta  cx16.VERA_ADDR_L
-		sty  cx16.VERA_ADDR_M
-        lda  cx16.VERA_DATA0
-		rts
+            asl  a
+            stz  cx16.VERA_CTRL
+            stz  cx16.VERA_ADDR_H
+            sta  cx16.VERA_ADDR_L
+            sty  cx16.VERA_ADDR_M
+            lda  cx16.VERA_DATA0
+            rts
 	}}
 }
 
 asmsub  setclr  (ubyte col @X, ubyte row @Y, ubyte color @A) clobbers(A)  {
 	; ---- set the color in A on the screen matrix at the given position
+	;      note: on the CommanderX16 this allows you to set both Fg and Bg colors;
+	;            use the high nybble in A to set the Bg color!
 	%asm {{
-		pha
-		txa
-		asl  a
-		ina
-        stz  cx16.VERA_CTRL
-		stz  cx16.VERA_ADDR_H
-		sta  cx16.VERA_ADDR_L
-		sty  cx16.VERA_ADDR_M
-		pla
-        sta  cx16.VERA_DATA0
-		rts
+            pha
+            txa
+            asl  a
+            ina
+            stz  cx16.VERA_CTRL
+            stz  cx16.VERA_ADDR_H
+            sta  cx16.VERA_ADDR_L
+            sty  cx16.VERA_ADDR_M
+            pla
+            sta  cx16.VERA_DATA0
+            rts
 	}}
 }
 
 asmsub  getclr  (ubyte col @A, ubyte row @Y) -> ubyte @ A {
 	; ---- get the color in the screen color matrix at the given location
 	%asm  {{
-		asl  a
-		ina
-        stz  cx16.VERA_CTRL
-		stz  cx16.VERA_ADDR_H
-		sta  cx16.VERA_ADDR_L
-		sty  cx16.VERA_ADDR_M
-        lda  cx16.VERA_DATA0
-		rts
+            asl  a
+            ina
+            stz  cx16.VERA_CTRL
+            stz  cx16.VERA_ADDR_H
+            sta  cx16.VERA_ADDR_L
+            sty  cx16.VERA_ADDR_M
+            lda  cx16.VERA_DATA0
+            rts
 	}}
 }
 
 sub  setcc  (ubyte column, ubyte row, ubyte char, ubyte charcolor)  {
 	; ---- set char+color at the given position on the screen
+	;      note: color handling is the same as on the C64: it only sets the foreground color.
+	;            use setcc2 if you want Cx-16 specific feature of setting both Bg+Fg colors.
 	%asm {{
-	    phx
-		lda  column
-		asl  a
-		tax
-		ldy  row
-		lda  charcolor
-		and  #$0f
-	    sta  P8ZP_SCRATCH_B1
-        stz  cx16.VERA_CTRL
-        stz  cx16.VERA_ADDR_H
-        stx  cx16.VERA_ADDR_L
-        sty  cx16.VERA_ADDR_M
-        lda  char
-        sta  cx16.VERA_DATA0
-        inx
-        stz  cx16.VERA_ADDR_H
-        stx  cx16.VERA_ADDR_L
-        sty  cx16.VERA_ADDR_M
-        lda  cx16.VERA_DATA0
-        and  #$f0
-        ora  P8ZP_SCRATCH_B1
-        sta  cx16.VERA_DATA0
-		plx
-		rts
+            phx
+            lda  column
+            asl  a
+            tax
+            ldy  row
+            lda  charcolor
+            and  #$0f
+            sta  P8ZP_SCRATCH_B1
+            stz  cx16.VERA_CTRL
+            stz  cx16.VERA_ADDR_H
+            stx  cx16.VERA_ADDR_L
+            sty  cx16.VERA_ADDR_M
+            lda  char
+            sta  cx16.VERA_DATA0
+            inx
+            stz  cx16.VERA_ADDR_H
+            stx  cx16.VERA_ADDR_L
+            sty  cx16.VERA_ADDR_M
+            lda  cx16.VERA_DATA0
+            and  #$f0
+            ora  P8ZP_SCRATCH_B1
+            sta  cx16.VERA_DATA0
+            plx
+            rts
+    }}
+}
+
+sub  setcc2  (ubyte column, ubyte row, ubyte char, ubyte colors)  {
+	; ---- set char+color at the given position on the screen
+	;      note: on the CommanderX16 this allows you to set both Fg and Bg colors;
+	;            use the high nybble in A to set the Bg color!
+	%asm {{
+            phx
+            lda  column
+            asl  a
+            tax
+            ldy  row
+            stz  cx16.VERA_CTRL
+            stz  cx16.VERA_ADDR_H
+            stx  cx16.VERA_ADDR_L
+            sty  cx16.VERA_ADDR_M
+            lda  char
+            sta  cx16.VERA_DATA0
+            inx
+            stz  cx16.VERA_ADDR_H
+            stx  cx16.VERA_ADDR_L
+            sty  cx16.VERA_ADDR_M
+            lda  colors
+            sta  cx16.VERA_DATA0
+            plx
+            rts
     }}
 }
 
 asmsub  plot  (ubyte col @ Y, ubyte row @ A) clobbers(A) {
-	; ---- safe wrapper around PLOT kernel routine, to save the X register.
+	; ---- safe wrapper around PLOT kernal routine, to save the X register.
 	%asm  {{
 		phx
 		tax

compiler/res/prog8lib/diskio.p8

@@ -30,7 +30,7 @@ diskio {
             ubyte low = c64.CHRIN()
             ubyte high = c64.CHRIN()
             txt.print_uw(mkword(high, low))
-            txt.chrout(' ')
+            txt.spc()
             ubyte @zp char
             repeat {
                 char = c64.CHRIN()
@@ -72,7 +72,7 @@ io_error:
     str   list_filename = "?" * 32
 
 
-    ; ----- get a list of files (uses iteration functions internally -----
+    ; ----- get a list of files (uses iteration functions internally) -----
 
     sub list_files(ubyte drivenumber, uword pattern_ptr, uword name_ptrs, ubyte max_names) -> ubyte {
         ; -- fill the array 'name_ptrs' with (pointers to) the names of the files requested.
@@ -295,7 +295,8 @@ _in_buffer      sta  $ffff
         ; Routine to read text lines from a text file. Lines must be less than 255 characters.
         ; Reads characters from the input file UNTIL a newline or return character (or EOF).
         ; The line read will be 0-terminated in the buffer (and not contain the end of line character).
-        ; The length of the line is returned in Y.
+        ; The length of the line is returned in Y. Note that an empty line is okay and is length 0!
+        ; I/O error status should be checked by the caller itself via READST() routine.
         %asm {{
             sta  P8ZP_SCRATCH_W1
             sty  P8ZP_SCRATCH_W1+1
@@ -335,6 +336,45 @@ _end        rts
     }
 
 
+    ; ----- iterative file saver functions (uses io channel 14) -----
+
+    sub f_open_w(ubyte drivenumber, uword filenameptr) -> ubyte {
+        ; -- open a file for iterative writing with f_write
+        f_close_w()
+
+        c64.SETNAM(string.length(filenameptr), filenameptr)
+        c64.SETLFS(14, drivenumber, 1)
+        void c64.OPEN()          ; open 14,8,1,"filename"
+        if_cc {
+            void c64.CHKOUT(14)        ; use #14 as input channel
+            return not c64.READST()
+        }
+        f_close_w()
+        return false
+    }
+
+    sub f_write(uword bufferpointer, uword num_bytes) -> ubyte {
+        ; -- write the given umber of bytes to the currently open file
+        if num_bytes!=0 {
+            void c64.CHKOUT(14)        ; use #14 as input channel again
+            repeat num_bytes {
+                c64.CHROUT(@(bufferpointer))
+                bufferpointer++
+            }
+            return not c64.READST()
+        }
+        return true
+    }
+
+    sub f_close_w() {
+        ; -- end an iterative file writing session (close channels).
+        c64.CLRCHN()
+        c64.CLOSE(14)
+    }
+
+
+    ; ---- other functions ----
+
     sub status(ubyte drivenumber) -> uword {
         ; -- retrieve the disk drive's current status message
         uword messageptr = &filename
@@ -352,18 +392,22 @@ _end        rts
             messageptr++
         }
 
-io_error:
         @(messageptr) = 0
+done:
         c64.CLRCHN()        ; restore default i/o devices
         c64.CLOSE(15)
         return filename
-    }
 
+io_error:
+        filename = "?disk error"
+        goto done
+    }
 
     sub save(ubyte drivenumber, uword filenameptr, uword address, uword size) -> ubyte {
         c64.SETNAM(string.length(filenameptr), filenameptr)
         c64.SETLFS(1, drivenumber, 0)
         uword end_address = address + size
+        first_byte = 0      ; result var reuse
 
         %asm {{
             lda  address
@@ -380,7 +424,6 @@ io_error:
             plp
         }}
 
-        first_byte = 0      ; result var reuse
         if_cc
             first_byte = c64.READST()==0
 
@@ -423,10 +466,9 @@ io_error:
 
     sub delete(ubyte drivenumber, uword filenameptr) {
         ; -- delete a file on the drive
-        ubyte flen = string.length(filenameptr)
         filename[0] = 's'
         filename[1] = ':'
-        sys.memcopy(filenameptr, &filename+2, flen+1)
+        ubyte flen = string.copy(filenameptr, &filename+2)
         c64.SETNAM(flen+2, filename)
         c64.SETLFS(1, drivenumber, 15)
         void c64.OPEN()
@@ -436,13 +478,11 @@ io_error:
 
     sub rename(ubyte drivenumber, uword oldfileptr, uword newfileptr) {
         ; -- rename a file on the drive
-        ubyte flen_old = string.length(oldfileptr)
-        ubyte flen_new = string.length(newfileptr)
         filename[0] = 'r'
         filename[1] = ':'
-        sys.memcopy(newfileptr, &filename+2, flen_new)
+        ubyte flen_new = string.copy(newfileptr, &filename+2)
         filename[flen_new+2] = '='
-        sys.memcopy(oldfileptr, &filename+3+flen_new, flen_old+1)
+        ubyte flen_old = string.copy(oldfileptr, &filename+3+flen_new)
         c64.SETNAM(3+flen_new+flen_old, filename)
         c64.SETLFS(1, drivenumber, 15)
         void c64.OPEN()

compiler/res/prog8lib/math.asm

@@ -244,68 +244,45 @@ randseed	.proc
 		.pend
 
 
-randbyte	.proc
-	; -- 8-bit pseudo random number generator into A
-		lda  _seed
-		beq  _eor
-		asl  a
-		beq  _done	; if the input was $80, skip the EOR
-		bcc  _done
-_eor		eor  #$1d	; xor with magic value see below for possible values
-_done		sta  _seed
-		rts
-
-_seed		.byte  $3a
-
-		; possible 'magic' eor bytes are:
-		; $1d, $2b, $2d, $4d, $5f, $63, $65, $69
-		; $71, $87, $8d, $a9, $c3, $cf, $e7, $f5
-
+randbyte        .proc
+	; -- 8 bit pseudo random number generator into A (by just reusing randword)
+		jmp  randword
 		.pend
 
-
 randword	.proc
 	; -- 16 bit pseudo random number generator into AY
 
-magic_eor = $3f1d
-		; possible magic eor words are:
-		; $3f1d, $3f81, $3fa5, $3fc5, $4075, $409d, $40cd, $4109
- 		; $413f, $414b, $4153, $4159, $4193, $4199, $41af, $41bb
+		; rand64k       ;Factors of 65535: 3 5 17 257
+		lda sr1+1
+		asl a
+		asl a
+		eor sr1+1
+		asl a
+		eor sr1+1
+		asl a
+		asl a
+		eor sr1+1
+		asl a
+		rol sr1         ;shift this left, "random" bit comes from low
+		rol sr1+1
+		; rand32k       ;Factors of 32767: 7 31 151 are independent and can be combined
+		lda sr2+1
+		asl a
+		eor sr2+1
+		asl a
+		asl a
+		ror sr2         ;shift this right, random bit comes from high - nicer when eor with sr1
+		rol sr2+1
+		lda sr1+1         ;can be left out
+		eor sr2+1         ;if you dont use
+		tay               ;y as suggested
+		lda sr1           ;mix up lowbytes of SR1
+		eor sr2           ;and SR2 to combine both
+		rts
 
-		lda  _seed
-		beq  _lowZero	; $0000 and $8000 are special values to test for
+sr1     	.word $a55a
+sr2     	.word $7653
 
- 		; Do a normal shift
-		asl  _seed
-		lda  _seed+1
-		rol  a
-		bcc  _noEor
-
-_doEor		; high byte is in A
-		eor  #>magic_eor
-  		sta  _seed+1
-  		lda  _seed
-  		eor  #<magic_eor
-  		sta  _seed
-  		ldy  _seed+1
-  		rts
-
-_lowZero	lda  _seed+1
-		beq  _doEor	; High byte is also zero, so apply the EOR
-				; For speed, you could store 'magic' into 'seed' directly
-				; instead of running the EORs
-
- 		; wasn't zero, check for $8000
-		asl  a
-		beq  _noEor	; if $00 is left after the shift, then it was $80
-		bcs  _doEor	; else, do the EOR based on the carry bit as usual
-
-_noEor		sta  _seed+1
-		tay
-		lda  _seed
- 		rts
-
-_seed		.word	$2c9e
 		.pend
 
 
@@ -797,6 +774,13 @@ stack_mul_word_320	.proc
 		rts
 		.pend
 
+stack_mul_word_640	.proc
+		; stackW = (stackLo * 2 * 320)    (stackHi doesn't matter)
+		asl  P8ESTACK_LO+1,x
+		jmp  stack_mul_word_320
+		.pend
+
+
 ; ----------- optimized multiplications (in-place A (byte) and ?? (word)) : ---------
 mul_byte_3	.proc
 		; A = A + A*2
@@ -1262,7 +1246,7 @@ mul_word_100	.proc
 		.pend
 
 mul_word_320	.proc
-		; AY = A * 256 + A * 64	 (msb doesn't matter)
+		; AY = A * 256 + A * 64	 (msb in Y doesn't matter)
 		sta  P8ZP_SCRATCH_B1
 		ldy  #0
 		sty  P8ZP_SCRATCH_REG
@@ -1287,6 +1271,13 @@ mul_word_320	.proc
 		rts
 		.pend
 
+mul_word_640	.proc
+		; AY = (A * 2 * 320) (msb in Y doesn't matter)
+		asl  a
+		jmp  mul_word_320
+		.pend
+
+
 ; ----------- end optimized multiplications -----------
 
 
@@ -1537,3 +1528,71 @@ _negative	lsr  a
 		rts
 		.pend
 
+
+square          .proc
+; -- calculate square root of signed word in AY, result in AY
+; routine by Lee Davsion, source: http://6502.org/source/integers/square.htm
+; using this routine is about twice as fast as doing a regular multiplication.
+;
+; Calculates the 16 bit unsigned integer square of the signed 16 bit integer in
+; Numberl/Numberh.  The result is always in the range 0 to 65025 and is held in
+; Squarel/Squareh
+;
+; The maximum input range is only +/-255 and no checking is done to ensure that
+; this is so.
+;
+; This routine is useful if you are trying to draw circles as for any circle
+;
+; x^2+y^2=r^2 where x and y are the co-ordinates of any point on the circle and
+; r is the circle radius
+
+numberl = P8ZP_SCRATCH_W1       ; number to square low byte
+numberh = P8ZP_SCRATCH_W1+1     ; number to square high byte
+squarel = P8ZP_SCRATCH_W2       ; square low byte
+squareh = P8ZP_SCRATCH_W2+1     ; square high byte
+tempsq = P8ZP_SCRATCH_B1        ; temp byte for intermediate result
+
+	sta  numberl
+	sty  numberh
+	stx  P8ZP_SCRATCH_REG
+
+        lda     #$00        ; clear a
+        sta     squarel     ; clear square low byte
+                            ; (no need to clear the high byte, it gets shifted out)
+        lda	numberl     ; get number low byte
+	ldx	numberh     ; get number high  byte
+	bpl	_nonneg      ; if +ve don't negate it
+                            ; else do a two's complement
+	eor	#$ff        ; invert
+        sec	            ; +1
+	adc	#$00        ; and add it
+
+_nonneg:
+	sta	tempsq      ; save abs(number)
+	ldx	#$08        ; set bit count
+
+_nextr2bit:
+	asl	squarel     ; low byte *2
+	rol	squareh     ; high byte *2+carry from low
+	asl	a           ; shift number byte
+	bcc	_nosqadd     ; don't do add if c = 0
+	tay                 ; save a
+	clc                 ; clear carry for add
+	lda	tempsq      ; get number
+	adc	squarel     ; add number^2 low byte
+	sta	squarel     ; save number^2 low byte
+	lda	#$00        ; clear a
+	adc	squareh     ; add number^2 high byte
+	sta	squareh     ; save number^2 high byte
+	tya                 ; get a back
+
+_nosqadd:
+	dex                 ; decrement bit count
+	bne	_nextr2bit   ; go do next bit
+
+	lda  squarel
+	ldy  squareh
+	ldx  P8ZP_SCRATCH_REG
+	rts
+
+		.pend

compiler/res/prog8lib/math.p8

@@ -3,5 +3,5 @@
 ; Written by Irmen de Jong (irmen@razorvine.net) - license: GNU GPL 3.0
 
 math {
-	%asminclude "library:math.asm", ""
+	%asminclude "library:math.asm"
 }

compiler/res/prog8lib/prog8_funcs.asm

@@ -432,6 +432,7 @@ func_min_ub_stack	.proc
 func_min_b_into_A	.proc
 		; -- min(barray) -> A.  (array in P8ZP_SCRATCH_W1, num elements in A)
 		tay
+		dey
 		lda  #127
 		sta  P8ZP_SCRATCH_B1
 -		lda  (P8ZP_SCRATCH_W1),y
@@ -548,6 +549,7 @@ func_min_w_stack	.proc
 func_max_ub_into_A	.proc
 		; -- max(ubarray) -> A  (array in P8ZP_SCRATCH_W1, num elements in A)
 		tay
+		dey
 		lda  #0
 		sta  P8ZP_SCRATCH_B1
 -		lda  (P8ZP_SCRATCH_W1),y
@@ -1078,3 +1080,28 @@ _loop_hi	ldy  _index_first
 		.pend
 
 
+func_peekw   .proc
+	; -- read the word value on the address in AY
+	sta  P8ZP_SCRATCH_W1
+	sty  P8ZP_SCRATCH_W1+1
+	ldy  #0
+	lda  (P8ZP_SCRATCH_W1),y
+	pha
+	iny
+	lda  (P8ZP_SCRATCH_W1),y
+	tay
+	pla
+	rts
+	.pend
+
+
+func_pokew   .proc
+	; -- store the word value in AY in the address in P8ZP_SCRATCH_W1
+	sty  P8ZP_SCRATCH_REG
+	ldy  #0
+	sta  (P8ZP_SCRATCH_W1),y
+	iny
+	lda  P8ZP_SCRATCH_REG
+	sta  (P8ZP_SCRATCH_W1),y
+	rts
+	.pend

compiler/res/prog8lib/prog8_lib.asm

@@ -1071,3 +1071,15 @@ sign_extend_AY_byte	.proc
 		pla
 		rts
 		.pend
+
+strlen          .proc
+        ; -- returns the number of bytes in the string in AY, in Y.
+		sta  P8ZP_SCRATCH_W1
+		sty  P8ZP_SCRATCH_W1+1
+		ldy  #0
+-		lda  (P8ZP_SCRATCH_W1),y
+		beq  +
+		iny
+		bne  -
++		rts
+		.pend

compiler/res/prog8lib/prog8_lib.p8

@@ -3,13 +3,15 @@
 ; Written by Irmen de Jong (irmen@razorvine.net) - license: GNU GPL 3.0
 
 prog8_lib {
-	%asminclude "library:prog8_lib.asm", ""
-	%asminclude "library:prog8_funcs.asm", ""
+	%asminclude "library:prog8_lib.asm"
+	%asminclude "library:prog8_funcs.asm"
 
+        ; TODO these retval variables are no longer used???
 	uword @zp retval_interm_uw      ; to store intermediary expression results for return values (hopefully allocated on ZP to reduce code size)
 	word @zp retval_interm_w        ; to store intermediary expression results for return values (hopefully allocated on ZP to reduce code size)
 	ubyte @zp retval_interm_ub      ; to store intermediary expression results for return values (hopefully allocated on ZP to reduce code size)
 	byte @zp retval_interm_b        ; to store intermediary expression results for return values (hopefully allocated on ZP to reduce code size)
+	; NOTE: these variables are checked in the StatementReorderer (in fun after(decl: VarDecl)), for these exact names!
 
 	asmsub pattern_match(str string @AY, str pattern @R0) clobbers(Y) -> ubyte @A {
 		%asm {{

compiler/res/prog8lib/string.p8

@@ -178,7 +178,7 @@ _found		sty  P8ZP_SCRATCH_B1
 
     asmsub compare(uword string1 @R0, uword string2 @AY) clobbers(Y) -> byte @A {
         ; Compares two strings for sorting.
-        ; Returns -1 (255), 0 or 1 depeding on wether string1 sorts before, equal or after string2.
+        ; Returns -1 (255), 0 or 1 depending on wether string1 sorts before, equal or after string2.
         ; Note that you can also directly compare strings and string values with eachother using
         ; comparison operators ==, < etcetera (it will use strcmp for you under water automatically).
         %asm {{
@@ -190,8 +190,8 @@ _found		sty  P8ZP_SCRATCH_B1
         }}
     }
 
-    asmsub lower(uword st @AY) {
-        ; Lowercases the petscii string in-place.
+    asmsub lower(uword st @AY) -> ubyte @Y {
+        ; Lowercases the petscii string in-place. Returns length of the string.
         ; (for efficiency, non-letter characters > 128 will also not be left intact,
         ;  but regular text doesn't usually contain those characters anyway.)
         %asm {{
@@ -213,8 +213,8 @@ _done       rts
         }}
     }
 
-    asmsub upper(uword st @AY) {
-        ; Uppercases the petscii string in-place.
+    asmsub upper(uword st @AY) -> ubyte @Y {
+        ; Uppercases the petscii string in-place. Returns length of the string.
         %asm {{
             sta  P8ZP_SCRATCH_W1
             sty  P8ZP_SCRATCH_W1+1

compiler/res/version.txt

@@ -1 +1 @@
-6.0-BETA
+7.2

compiler/src/prog8/CompilerMain.kt

@@ -6,8 +6,7 @@ import prog8.compiler.CompilationResult
 import prog8.compiler.compileProgram
 import prog8.compiler.target.C64Target
 import prog8.compiler.target.Cx16Target
-import prog8.compiler.target.CompilationTarget
-import prog8.parser.ParsingFailedError
+import java.io.File
 import java.nio.file.FileSystems
 import java.nio.file.Path
 import java.nio.file.StandardWatchEventKinds
@@ -16,45 +15,57 @@ import kotlin.system.exitProcess
 
 
 fun main(args: Array<String>) {
-    printSoftwareHeader("compiler")
-
-    compileMain(args)
-}
-
-internal fun printSoftwareHeader(what: String) {
     val buildVersion = object {}.javaClass.getResource("/version.txt").readText().trim()
-    println("\nProg8 $what v$buildVersion by Irmen de Jong (irmen@razorvine.net)")
+    println("\nProg8 compiler v$buildVersion by Irmen de Jong (irmen@razorvine.net)")
     println("This software is licensed under the GNU GPL 3.0, see https://www.gnu.org/licenses/gpl.html\n")
+
+    val succes = compileMain(args)
+    if(!succes)
+        exitProcess(1)
 }
 
 
 fun pathFrom(stringPath: String, vararg rest: String): Path  = FileSystems.getDefault().getPath(stringPath, *rest)
 
 
-private fun compileMain(args: Array<String>) {
-    val cli = ArgParser("prog8compiler")
-    val startEmulator by cli.option(ArgType.Boolean, shortName="emu", description = "auto-start emulator after successful compilation")
-    val outputDir by cli.option(ArgType.String, shortName = "out", description = "directory for output files instead of current directory").default(".")
-    val dontWriteAssembly by cli.option(ArgType.Boolean, shortName = "noasm", description="don't create assembly code")
-    val dontOptimize by cli.option(ArgType.Boolean, shortName = "noopt", description = "don't perform any optimizations")
-    val watchMode by cli.option(ArgType.Boolean, shortName = "watch", description = "continuous compilation mode (watches for file changes), greatly increases compilation speed")
-    val slowCodegenWarnings by cli.option(ArgType.Boolean, shortName = "slowwarn", description="show debug warnings about slow/problematic assembly code generation")
-    val compilationTarget by cli.option(ArgType.String, shortName = "target", description = "target output of the compiler, currently '${C64Target.name}' and '${Cx16Target.name}' available").default(C64Target.name)
+private fun compileMain(args: Array<String>): Boolean {
+    val cli = ArgParser("prog8compiler", prefixStyle = ArgParser.OptionPrefixStyle.JVM)
+    val startEmulator1 by cli.option(ArgType.Boolean, fullName = "emu", description = "auto-start emulator after successful compilation")
+    val startEmulator2 by cli.option(ArgType.Boolean, fullName = "emu2", description = "auto-start alternative emulator after successful compilation")
+    val outputDir by cli.option(ArgType.String, fullName = "out", description = "directory for output files instead of current directory").default(".")
+    val dontWriteAssembly by cli.option(ArgType.Boolean, fullName = "noasm", description="don't create assembly code")
+    val dontOptimize by cli.option(ArgType.Boolean, fullName = "noopt", description = "don't perform any optimizations")
+    val optimizeFloatExpressions by cli.option(ArgType.Boolean, fullName = "optfloatx", description = "optimize float expressions (warning: can increase program size)")
+    val watchMode by cli.option(ArgType.Boolean, fullName = "watch", description = "continuous compilation mode (watches for file changes), greatly increases compilation speed")
+    val slowCodegenWarnings by cli.option(ArgType.Boolean, fullName = "slowwarn", description="show debug warnings about slow/problematic assembly code generation")
+    val quietAssembler by cli.option(ArgType.Boolean, fullName = "quietasm", description = "don't print assembler output results")
+    val compilationTarget by cli.option(ArgType.String, fullName = "target", description = "target output of the compiler, currently '${C64Target.name}' and '${Cx16Target.name}' available").default(C64Target.name)
+    val sourceDirs by cli.option(ArgType.String, fullName="srcdirs", description = "list of extra paths, separated with ${File.pathSeparator}, to search in for imported modules").multiple().delimiter(File.pathSeparator)
     val moduleFiles by cli.argument(ArgType.String, fullName = "modules", description = "main module file(s) to compile").multiple(999)
 
     try {
         cli.parse(args)
     } catch (e: IllegalStateException) {
         System.err.println(e.message)
-        exitProcess(1)
+        return false
     }
 
     val outputPath = pathFrom(outputDir)
     if(!outputPath.toFile().isDirectory) {
         System.err.println("Output path doesn't exist")
-        exitProcess(1)
+        return false
     }
 
+    val faultyOption = moduleFiles.firstOrNull { it.startsWith('-') }
+    if(faultyOption!=null) {
+        System.err.println("Unknown command line option given: $faultyOption")
+        return false
+    }
+
+    val srcdirs = sourceDirs.toMutableList()
+    if(srcdirs.firstOrNull()!=".")
+        srcdirs.add(0, ".")
+
     if(watchMode==true) {
         val watchservice = FileSystems.getDefault().newWatchService()
         val allImportedFiles = mutableSetOf<Path>()
@@ -64,7 +75,10 @@ private fun compileMain(args: Array<String>) {
             val results = mutableListOf<CompilationResult>()
             for(filepathRaw in moduleFiles) {
                 val filepath = pathFrom(filepathRaw).normalize()
-                val compilationResult = compileProgram(filepath, dontOptimize!=true, dontWriteAssembly!=true, slowCodegenWarnings==true, compilationTarget, outputPath)
+                val compilationResult = compileProgram(filepath,
+                    dontOptimize!=true, optimizeFloatExpressions==true,
+                    dontWriteAssembly!=true, slowCodegenWarnings==true, quietAssembler==true,
+                    compilationTarget, srcdirs, outputPath)
                 results.add(compilationResult)
             }
 
@@ -75,7 +89,7 @@ private fun compileMain(args: Array<String>) {
             for (importedFile in allImportedFiles) {
                 print("  ")
                 println(importedFile)
-                val watchDir = importedFile.parent ?: Path.of(".")
+                val watchDir = importedFile.parent ?: Path.of("")
                 watchDir.register(watchservice, StandardWatchEventKinds.ENTRY_MODIFY)
             }
             println("[${LocalDateTime.now().withNano(0)}]  Waiting for file changes.")
@@ -101,22 +115,31 @@ private fun compileMain(args: Array<String>) {
             val filepath = pathFrom(filepathRaw).normalize()
             val compilationResult: CompilationResult
             try {
-                compilationResult = compileProgram(filepath, dontOptimize!=true, dontWriteAssembly!=true, slowCodegenWarnings==true, compilationTarget, outputPath)
+                compilationResult = compileProgram(filepath,
+                    dontOptimize!=true, optimizeFloatExpressions==true,
+                    dontWriteAssembly!=true, slowCodegenWarnings==true, quietAssembler==true,
+                    compilationTarget, srcdirs, outputPath)
                 if(!compilationResult.success)
-                    exitProcess(1)
-            } catch (x: ParsingFailedError) {
-                exitProcess(1)
+                    return false
             } catch (x: AstException) {
-                exitProcess(1)
+                return false
             }
 
-            if (startEmulator==true) {
-                if (compilationResult.programName.isEmpty())
+            if(startEmulator1==true || startEmulator2==true) {
+                if (compilationResult.programName.isEmpty()) {
                     println("\nCan't start emulator because no program was assembled.")
-                else {
-                    CompilationTarget.instance.machine.launchEmulator(compilationResult.programName)
+                    return true
                 }
             }
+
+            val programNameInPath = outputPath.resolve(compilationResult.programName)
+
+            if (startEmulator1==true)
+                compilationResult.compTarget.machine.launchEmulator(1, programNameInPath)
+            else if (startEmulator2==true)
+                compilationResult.compTarget.machine.launchEmulator(2, programNameInPath)
         }
     }
+
+    return true
 }

compiler/src/prog8/ast/AstToplevel.kt

@@ -1,382 +0,0 @@
-package prog8.ast
-
-import prog8.ast.base.*
-import prog8.ast.expressions.Expression
-import prog8.ast.expressions.IdentifierReference
-import prog8.ast.processing.AstWalker
-import prog8.ast.processing.IAstVisitor
-import prog8.ast.statements.*
-import prog8.functions.BuiltinFunctions
-import java.nio.file.Path
-
-
-interface Node {
-    val position: Position
-    var parent: Node             // will be linked correctly later (late init)
-    fun linkParents(parent: Node)
-
-    fun definingModule(): Module {
-        if(this is Module)
-            return this
-        return findParentNode<Module>(this)!!
-    }
-
-    fun definingSubroutine(): Subroutine?  = findParentNode<Subroutine>(this)
-
-    fun definingScope(): INameScope {
-        val scope = findParentNode<INameScope>(this)
-        if(scope!=null) {
-            return scope
-        }
-        if(this is Label && this.name.startsWith("builtin::")) {
-            return BuiltinFunctionScopePlaceholder
-        }
-        if(this is GlobalNamespace)
-            return this
-        throw FatalAstException("scope missing from $this")
-    }
-
-    fun definingBlock(): Block {
-        if(this is Block)
-            return this
-        return findParentNode<Block>(this)!!
-    }
-
-    fun containingStatement(): Statement {
-        if(this is Statement)
-            return this
-        return findParentNode<Statement>(this)!!
-    }
-
-    fun replaceChildNode(node: Node, replacement: Node)
-}
-
-interface IFunctionCall {
-    var target: IdentifierReference
-    var args: MutableList<Expression>
-}
-
-
-interface INameScope {
-    val name: String
-    val position: Position
-    val statements: MutableList<Statement>
-    val parent: Node
-
-    fun linkParents(parent: Node)
-
-    fun subScope(name: String): INameScope? {
-        for(stmt in statements) {
-            when(stmt) {
-                // NOTE: if other nodes are introduced that are a scope, or contain subscopes, they must be added here!
-                is ForLoop -> if(stmt.body.name==name) return stmt.body
-                is UntilLoop -> if(stmt.body.name==name) return stmt.body
-                is WhileLoop -> if(stmt.body.name==name) return stmt.body
-                is BranchStatement -> {
-                    if(stmt.truepart.name==name) return stmt.truepart
-                    if(stmt.elsepart.containsCodeOrVars() && stmt.elsepart.name==name) return stmt.elsepart
-                }
-                is IfStatement -> {
-                    if(stmt.truepart.name==name) return stmt.truepart
-                    if(stmt.elsepart.containsCodeOrVars() && stmt.elsepart.name==name) return stmt.elsepart
-                }
-                is WhenStatement -> {
-                    val scope = stmt.choices.firstOrNull { it.statements.name==name }
-                    if(scope!=null)
-                        return scope.statements
-                }
-                is INameScope -> if(stmt.name==name) return stmt
-                else -> {}
-            }
-        }
-        return null
-    }
-
-    fun getLabelOrVariable(name: String): Statement? {
-        // this is called A LOT and could perhaps be optimized a bit more,
-        // but adding a memoization cache didn't make much of a practical runtime difference
-        for (stmt in statements) {
-            if (stmt is VarDecl && stmt.name==name) return stmt
-            if (stmt is Label && stmt.name==name) return stmt
-            if (stmt is AnonymousScope) {
-                val sub = stmt.getLabelOrVariable(name)
-                if(sub!=null)
-                    return sub
-            }
-        }
-        return null
-    }
-
-    fun allDefinedSymbols(): List<Pair<String, Statement>>  {
-        return statements.mapNotNull {
-            when (it) {
-                is Label -> it.name to it
-                is VarDecl -> it.name to it
-                is Subroutine -> it.name to it
-                is Block -> it.name to it
-                else -> null
-            }
-        }
-    }
-
-    fun lookup(scopedName: List<String>, localContext: Node) : Statement? {
-        if(scopedName.size>1) {
-            // a scoped name can a) refer to a member of a struct, or b) refer to a name in another module.
-            // try the struct first.
-            val thing = lookup(scopedName.dropLast(1), localContext) as? VarDecl
-            val struct = thing?.struct
-            if (struct != null) {
-                if(struct.statements.any { (it as VarDecl).name == scopedName.last()}) {
-                    // return ref to the mangled name variable
-                    val mangled = mangledStructMemberName(thing.name, scopedName.last())
-                    return thing.definingScope().getLabelOrVariable(mangled)
-                }
-            }
-
-            // it's a qualified name, look it up from the root of the module's namespace (consider all modules in the program)
-            for(module in localContext.definingModule().program.modules) {
-                var scope: INameScope? = module
-                for(name in scopedName.dropLast(1)) {
-                    scope = scope?.subScope(name)
-                    if(scope==null)
-                        break
-                }
-                if(scope!=null) {
-                    val result = scope.getLabelOrVariable(scopedName.last())
-                    if(result!=null)
-                        return result
-                    return scope.subScope(scopedName.last()) as Statement?
-                }
-            }
-            return null
-        } else {
-            // unqualified name
-            // special case: the do....until statement can also look INSIDE the anonymous scope
-            if(localContext.parent.parent is UntilLoop) {
-                val symbolFromInnerScope = (localContext.parent.parent as UntilLoop).body.getLabelOrVariable(scopedName[0])
-                if(symbolFromInnerScope!=null)
-                    return symbolFromInnerScope
-            }
-
-            // find the scope the localContext is in, look in that first
-            var statementScope = localContext
-            while(statementScope !is ParentSentinel) {
-                val localScope = statementScope.definingScope()
-                val result = localScope.getLabelOrVariable(scopedName[0])
-                if (result != null)
-                    return result
-                val subscope = localScope.subScope(scopedName[0]) as Statement?
-                if (subscope != null)
-                    return subscope
-                // not found in this scope, look one higher up
-                statementScope = statementScope.parent
-            }
-            return null
-        }
-    }
-
-    fun containsDefinedVariables() = statements.any { it is VarDecl && (it !is ParameterVarDecl) }
-    fun containsCodeOrVars() = statements.any { it !is Directive || it.directive == "%asminclude" || it.directive == "%asm"}
-    fun containsNoCodeNorVars() = !containsCodeOrVars()
-
-    fun remove(stmt: Statement) {
-        if(!statements.remove(stmt))
-            throw FatalAstException("stmt to remove wasn't found in scope")
-    }
-
-    fun getAllLabels(label: String): List<Label> {
-        val result = mutableListOf<Label>()
-
-        fun find(scope: INameScope) {
-            scope.statements.forEach {
-                when(it) {
-                    is Label -> result.add(it)
-                    is INameScope -> find(it)
-                    is IfStatement -> {
-                        find(it.truepart)
-                        find(it.elsepart)
-                    }
-                    is UntilLoop -> find(it.body)
-                    is RepeatLoop -> find(it.body)
-                    is WhileLoop -> find(it.body)
-                    is WhenStatement -> it.choices.forEach { choice->find(choice.statements) }
-                    else -> { /* do nothing */ }
-                }
-            }
-        }
-
-        find(this)
-        return result
-    }
-
-    fun nextSibling(stmt: Statement): Statement? {
-        val nextIdx = statements.indexOfFirst { it===stmt } + 1
-        return if(nextIdx < statements.size)
-            statements[nextIdx]
-        else
-            null
-    }
-
-    fun previousSibling(stmt: Statement): Statement? {
-        val previousIdx = statements.indexOfFirst { it===stmt } - 1
-        return if(previousIdx>=0)
-            statements[previousIdx]
-        else
-            null
-    }
-
-    fun indexOfChild(stmt: Statement): Int {
-        val idx = statements.indexOfFirst { it===stmt }
-        if(idx>=0)
-            return idx
-        else
-            throw FatalAstException("attempt to find a non-child")
-    }
-}
-
-interface IAssignable {
-    // just a tag for now
-}
-
-
-/*********** Everything starts from here, the Program; zero or more modules *************/
-
-class Program(val name: String, val modules: MutableList<Module>): Node {
-    val namespace = GlobalNamespace(modules)
-
-    val definedLoadAddress: Int
-        get() = modules.first().loadAddress
-
-    var actualLoadAddress: Int = 0
-
-    fun entrypoint(): Subroutine? {
-        val mainBlocks = allBlocks().filter { it.name=="main" }
-        if(mainBlocks.size > 1)
-            throw FatalAstException("more than one 'main' block")
-        return if(mainBlocks.isEmpty()) {
-            null
-        } else {
-            mainBlocks[0].subScope("start") as Subroutine?
-        }
-    }
-
-    fun allBlocks(): List<Block> = modules.flatMap { it.statements.filterIsInstance<Block>() }
-
-    override val position: Position = Position.DUMMY
-    override var parent: Node
-        get() = throw FatalAstException("program has no parent")
-        set(_) = throw FatalAstException("can't set parent of program")
-
-    override fun linkParents(parent: Node) {
-        modules.forEach {
-            it.linkParents(namespace)
-        }
-    }
-
-    override fun replaceChildNode(node: Node, replacement: Node) {
-        require(node is Module && replacement is Module)
-        val idx = modules.indexOfFirst { it===node }
-        modules[idx] = replacement
-        replacement.parent = this
-    }
-}
-
-class Module(override val name: String,
-             override var statements: MutableList<Statement>,
-             override val position: Position,
-             val isLibraryModule: Boolean,
-             val source: Path) : Node, INameScope {
-
-    override lateinit var parent: Node
-    lateinit var program: Program
-    val importedBy = mutableListOf<Module>()
-    val imports = mutableSetOf<Module>()
-
-    val loadAddress: Int by lazy {
-        val address = (statements.singleOrNull { it is Directive && it.directive == "%address" } as? Directive)?.args?.single()?.int ?: 0
-        address
-    }
-
-    override fun linkParents(parent: Node) {
-        this.parent = parent
-        statements.forEach {it.linkParents(this)}
-    }
-
-    override fun definingScope(): INameScope = program.namespace
-    override fun replaceChildNode(node: Node, replacement: Node) {
-        require(node is Statement && replacement is Statement)
-        val idx = statements.indexOfFirst { it===node }
-        statements[idx] = replacement
-        replacement.parent = this
-    }
-
-    override fun toString() = "Module(name=$name, pos=$position, lib=$isLibraryModule)"
-
-    fun accept(visitor: IAstVisitor) = visitor.visit(this)
-    fun accept(visitor: AstWalker, parent: Node) = visitor.visit(this, parent)
-}
-
-
-class GlobalNamespace(val modules: List<Module>): Node, INameScope {
-    override val name = "<<<global>>>"
-    override val position = Position("<<<global>>>", 0, 0, 0)
-    override val statements = mutableListOf<Statement>()        // not used
-    override var parent: Node = ParentSentinel
-
-    override fun linkParents(parent: Node) {
-        modules.forEach { it.linkParents(this) }
-    }
-
-    override fun replaceChildNode(node: Node, replacement: Node) {
-        throw FatalAstException("cannot replace anything in the namespace")
-    }
-
-    override fun lookup(scopedName: List<String>, localContext: Node): Statement? {
-        if (scopedName.size == 1 && scopedName[0] in BuiltinFunctions) {
-            // builtin functions always exist, return a dummy localContext for them
-            val builtinPlaceholder = Label("builtin::${scopedName.last()}", localContext.position)
-            builtinPlaceholder.parent = ParentSentinel
-            return builtinPlaceholder
-        }
-
-        if(scopedName.size>1) {
-            // a scoped name can a) refer to a member of a struct, or b) refer to a name in another module.
-            // try the struct first.
-            val thing = lookup(scopedName.dropLast(1), localContext) as? VarDecl
-            val struct = thing?.struct
-            if (struct != null) {
-                if(struct.statements.any { (it as VarDecl).name == scopedName.last()}) {
-                    // return ref to the mangled name variable
-                    val mangled = mangledStructMemberName(thing.name, scopedName.last())
-                    return thing.definingScope().getLabelOrVariable(mangled)
-                }
-            }
-        }
-
-        // special case: the do....until statement can also look INSIDE the anonymous scope
-        if(localContext.parent.parent is UntilLoop) {
-            val symbolFromInnerScope = (localContext.parent.parent as UntilLoop).body.lookup(scopedName, localContext)
-            if(symbolFromInnerScope!=null)
-                return symbolFromInnerScope
-        }
-
-        // lookup something from the module.
-        return when (val stmt = localContext.definingModule().lookup(scopedName, localContext)) {
-            is Label, is VarDecl, is Block, is Subroutine, is StructDecl -> stmt
-            null -> null
-            else -> throw SyntaxError("invalid identifier target type", stmt.position)
-        }
-    }
-}
-
-object BuiltinFunctionScopePlaceholder : INameScope {
-    override val name = "<<builtin-functions-scope-placeholder>>"
-    override val position = Position("<<placeholder>>", 0, 0, 0)
-    override var statements = mutableListOf<Statement>()
-    override var parent: Node = ParentSentinel
-    override fun linkParents(parent: Node) {}
-}
-
-
-// prefix for struct member variables
-internal fun mangledStructMemberName(varName: String, memberName: String) = "prog8struct_${varName}_$memberName"

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

@@ -1,44 +0,0 @@
-package prog8.ast.base
-
-import prog8.parser.ParsingFailedError
-
-
-class ErrorReporter {
-    private enum class MessageSeverity {
-        WARNING,
-        ERROR
-    }
-    private class CompilerMessage(val severity: MessageSeverity, val message: String, val position: Position)
-
-    private val messages = mutableListOf<CompilerMessage>()
-    private val alreadyReportedMessages = mutableSetOf<String>()
-
-    fun err(msg: String, position: Position) = messages.add(CompilerMessage(MessageSeverity.ERROR, msg, position))
-    fun warn(msg: String, position: Position) = messages.add(CompilerMessage(MessageSeverity.WARNING, msg, position))
-
-    fun handle() {
-        var numErrors = 0
-        var numWarnings = 0
-        messages.forEach {
-            when(it.severity) {
-                MessageSeverity.ERROR -> System.err.print("\u001b[91m")  // bright red
-                MessageSeverity.WARNING -> System.err.print("\u001b[93m")  // bright yellow
-            }
-            val msg = "${it.position.toClickableStr()} ${it.severity} ${it.message}".trim()
-            if(msg !in alreadyReportedMessages) {
-                System.err.println(msg)
-                alreadyReportedMessages.add(msg)
-                when(it.severity) {
-                    MessageSeverity.WARNING -> numWarnings++
-                    MessageSeverity.ERROR -> numErrors++
-                }
-            }
-            System.err.print("\u001b[0m")  // reset color
-        }
-        messages.clear()
-        if(numErrors>0)
-            throw ParsingFailedError("There are $numErrors errors and $numWarnings warnings.")
-    }
-
-    fun isEmpty() = messages.isEmpty()
-}

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

@@ -1,102 +0,0 @@
-package prog8.ast.base
-
-import prog8.ast.Module
-import prog8.ast.Program
-import prog8.ast.processing.*
-import prog8.ast.statements.Directive
-import prog8.compiler.CompilationOptions
-import prog8.compiler.BeforeAsmGenerationAstChanger
-
-
-internal fun Program.checkValid(compilerOptions: CompilationOptions, errors: ErrorReporter) {
-    val checker = AstChecker(this, compilerOptions, errors)
-    checker.visit(this)
-}
-
-internal fun Program.processAstBeforeAsmGeneration(errors: ErrorReporter) {
-    val fixer = BeforeAsmGenerationAstChanger(this, errors)
-    fixer.visit(this)
-    fixer.applyModifications()
-}
-
-internal fun Program.reorderStatements(errors: ErrorReporter) {
-    val reorder = StatementReorderer(this, errors)
-    reorder.visit(this)
-    reorder.applyModifications()
-}
-
-internal fun Program.addTypecasts(errors: ErrorReporter) {
-    val caster = TypecastsAdder(this, errors)
-    caster.visit(this)
-    caster.applyModifications()
-}
-
-internal fun Program.verifyFunctionArgTypes() {
-    val fixer = VerifyFunctionArgTypes(this)
-    fixer.visit(this)
-}
-
-internal fun Module.checkImportedValid() {
-    val imr = ImportedModuleDirectiveRemover()
-    imr.visit(this, this.parent)
-    imr.applyModifications()
-}
-
-internal fun Program.checkIdentifiers(errors: ErrorReporter) {
-
-    val checker2 = AstIdentifiersChecker(this, errors)
-    checker2.visit(this)
-
-    if(errors.isEmpty()) {
-        val transforms = AstVariousTransforms(this)
-        transforms.visit(this)
-        transforms.applyModifications()
-        val lit2decl = LiteralsToAutoVars(this)
-        lit2decl.visit(this)
-        lit2decl.applyModifications()
-    }
-
-    if (modules.map { it.name }.toSet().size != modules.size) {
-        throw FatalAstException("modules should all be unique")
-    }
-}
-
-internal fun Program.variousCleanups() {
-    val process = VariousCleanups()
-    process.visit(this)
-    process.applyModifications()
-}
-
-internal fun Program.moveMainAndStartToFirst() {
-    // the module containing the program entrypoint is moved to the first in the sequence.
-    // the "main" block containing the entrypoint is moved to the top in there,
-    // and finally the entrypoint subroutine "start" itself is moved to the top in that block.
-
-    val directives = modules[0].statements.filterIsInstance<Directive>()
-    val start = this.entrypoint()
-    if(start!=null) {
-        val mod = start.definingModule()
-        val block = start.definingBlock()
-        if(!modules.remove(mod))
-            throw FatalAstException("module wrong")
-        modules.add(0, mod)
-        mod.remove(block)
-        var afterDirective = mod.statements.indexOfFirst { it !is Directive }
-        if(afterDirective<0)
-            mod.statements.add(block)
-        else
-            mod.statements.add(afterDirective, block)
-        block.remove(start)
-        afterDirective = block.statements.indexOfFirst { it !is Directive }
-        if(afterDirective<0)
-            block.statements.add(start)
-        else
-            block.statements.add(afterDirective, start)
-
-        // overwrite the directives in the module containing the entrypoint
-        for(directive in directives) {
-            modules[0].statements.removeAll { it is Directive && it.directive == directive.directive }
-            modules[0].statements.add(0, directive)
-        }
-    }
-}

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

@@ -1,176 +0,0 @@
-package prog8.ast.processing
-
-import prog8.ast.Module
-import prog8.ast.Program
-import prog8.ast.base.*
-import prog8.ast.expressions.*
-import prog8.ast.statements.*
-import prog8.compiler.target.CompilationTarget
-import prog8.functions.BuiltinFunctions
-
-internal class AstIdentifiersChecker(private val program: Program, private val errors: ErrorReporter) : IAstVisitor {
-    private var blocks = mutableMapOf<String, Block>()
-
-    private fun nameError(name: String, position: Position, existing: Statement) {
-        errors.err("name conflict '$name', also defined in ${existing.position.file} line ${existing.position.line}", position)
-    }
-
-    override fun visit(module: Module) {
-        blocks.clear()  // blocks may be redefined within a different module
-
-        super.visit(module)
-    }
-
-    override fun visit(block: Block) {
-        if(block.name in CompilationTarget.instance.machine.opcodeNames)
-            errors.err("can't use a cpu opcode name as a symbol: '${block.name}'", block.position)
-
-        val existing = blocks[block.name]
-        if(existing!=null)
-            nameError(block.name, block.position, existing)
-        else
-            blocks[block.name] = block
-
-        if(!block.isInLibrary) {
-            val libraries = program.modules.filter { it.isLibraryModule }
-            val libraryBlockNames = libraries.flatMap { it.statements.filterIsInstance<Block>().map { b -> b.name } }
-            if(block.name in libraryBlockNames)
-                errors.err("block is already defined in an included library module", block.position)
-        }
-
-        super.visit(block)
-    }
-
-    override fun visit(directive: Directive) {
-        if(directive.directive=="%target") {
-            val compatibleTarget = directive.args.single().name
-            if (compatibleTarget != CompilationTarget.instance.name)
-                errors.err("module's compilation target ($compatibleTarget) differs from active target (${CompilationTarget.instance.name})", directive.position)
-        }
-
-        super.visit(directive)
-    }
-
-    override fun visit(decl: VarDecl) {
-        decl.datatypeErrors.forEach { errors.err(it.message, it.position) }
-
-        if(decl.name in BuiltinFunctions)
-            errors.err("builtin function cannot be redefined", decl.position)
-
-        if(decl.name in CompilationTarget.instance.machine.opcodeNames)
-            errors.err("can't use a cpu opcode name as a symbol: '${decl.name}'", decl.position)
-
-        if(decl.datatype==DataType.STRUCT) {
-            if (decl.structHasBeenFlattened)
-                return super.visit(decl)    // don't do this multiple times
-
-            if (decl.struct == null) {
-                errors.err("undefined struct type", decl.position)
-                return super.visit(decl)
-            }
-
-            if (decl.struct!!.statements.any { (it as VarDecl).datatype !in NumericDatatypes })
-                return super.visit(decl)     // a non-numeric member, not supported. proper error is given by AstChecker later
-
-            if (decl.value is NumericLiteralValue) {
-                errors.err("you cannot initialize a struct using a single value", decl.position)
-                return super.visit(decl)
-            }
-
-            if (decl.value != null && decl.value !is ArrayLiteralValue) {
-                errors.err("initializing a struct requires array literal value", decl.value?.position ?: decl.position)
-                return super.visit(decl)
-            }
-        }
-
-        val existing = program.namespace.lookup(listOf(decl.name), decl)
-        if (existing != null && existing !== decl)
-            nameError(decl.name, decl.position, existing)
-
-        if(decl.definingBlock().name==decl.name)
-            nameError(decl.name, decl.position, decl.definingBlock())
-        if(decl.definingSubroutine()?.name==decl.name)
-            nameError(decl.name, decl.position, decl.definingSubroutine()!!)
-
-        super.visit(decl)
-    }
-
-    override fun visit(subroutine: Subroutine) {
-        if(subroutine.name in CompilationTarget.instance.machine.opcodeNames) {
-            errors.err("can't use a cpu opcode name as a symbol: '${subroutine.name}'", subroutine.position)
-        } else if(subroutine.name in BuiltinFunctions) {
-            // the builtin functions can't be redefined
-            errors.err("builtin function cannot be redefined", subroutine.position)
-        } else {
-            // already reported elsewhere:
-            // if (subroutine.parameters.any { it.name in BuiltinFunctions })
-            //    checkResult.add(NameError("builtin function name cannot be used as parameter", subroutine.position))
-
-            val existing = program.namespace.lookup(listOf(subroutine.name), subroutine)
-            if (existing != null && existing !== subroutine)
-                nameError(subroutine.name, subroutine.position, existing)
-
-            // check that there are no local variables, labels, or other subs that redefine the subroutine's parameters
-            val symbolsInSub = subroutine.allDefinedSymbols()
-            val namesInSub = symbolsInSub.map{ it.first }.toSet()
-            val paramNames = subroutine.parameters.map { it.name }.toSet()
-            val paramsToCheck = paramNames.intersect(namesInSub)
-            for(name in paramsToCheck) {
-                val labelOrVar = subroutine.getLabelOrVariable(name)
-                if(labelOrVar!=null && labelOrVar.position != subroutine.position)
-                    nameError(name, labelOrVar.position, subroutine)
-                val sub = subroutine.statements.firstOrNull { it is Subroutine && it.name==name}
-                if(sub!=null)
-                    nameError(name, subroutine.position, sub)
-                val block = program.allBlocks().firstOrNull { it.name==name }
-                if(block!=null)
-                    nameError(name, subroutine.position, block)
-            }
-
-            if(subroutine.isAsmSubroutine && subroutine.statements.any{it !is InlineAssembly}) {
-                errors.err("asmsub can only contain inline assembly (%asm)", subroutine.position)
-            }
-        }
-
-        super.visit(subroutine)
-    }
-
-    override fun visit(label: Label) {
-        if(label.name in CompilationTarget.instance.machine.opcodeNames)
-            errors.err("can't use a cpu opcode name as a symbol: '${label.name}'", label.position)
-
-        if(label.name in BuiltinFunctions) {
-            // the builtin functions can't be redefined
-            errors.err("builtin function cannot be redefined", label.position)
-        } else {
-            val existing = label.definingSubroutine()?.getAllLabels(label.name) ?: emptyList()
-            for(el in existing) {
-                if(el === label || el.name != label.name)
-                    continue
-                else {
-                    nameError(label.name, label.position, el)
-                    break
-                }
-            }
-        }
-
-        super.visit(label)
-    }
-
-    override fun visit(string: StringLiteralValue) {
-        if (string.value.length > 255)
-            errors.err("string literal length max is 255", string.position)
-
-        super.visit(string)
-    }
-
-    override fun visit(structDecl: StructDecl) {
-        for(member in structDecl.statements){
-            val decl = member as? VarDecl
-            if(decl!=null && decl.datatype !in NumericDatatypes)
-                errors.err("structs can only contain numerical types", decl.position)
-        }
-
-        super.visit(structDecl)
-    }
-}

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

@@ -1,22 +0,0 @@
-package prog8.ast.processing
-
-import prog8.ast.INameScope
-import prog8.ast.Node
-import prog8.ast.statements.Directive
-
-
-internal class ImportedModuleDirectiveRemover: AstWalker() {
-    /**
-     * Most global directives don't apply for imported modules, so remove them
-     */
-
-    private val moduleLevelDirectives = listOf("%output", "%launcher", "%zeropage", "%zpreserved", "%address")
-    private val noModifications = emptyList<IAstModification>()
-
-    override fun before(directive: Directive, parent: Node): Iterable<IAstModification> {
-        if(directive.directive in moduleLevelDirectives) {
-            return listOf(IAstModification.Remove(directive, parent as INameScope))
-        }
-        return noModifications
-    }
-}

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

@@ -1,416 +0,0 @@
-package prog8.ast.processing
-
-import prog8.ast.*
-import prog8.ast.base.*
-import prog8.ast.expressions.*
-import prog8.ast.statements.*
-import prog8.functions.BuiltinFunctions
-
-
-internal class StatementReorderer(val program: Program, val errors: ErrorReporter) : AstWalker() {
-    // Reorders the statements in a way the compiler needs.
-    // - 'main' block must be the very first statement UNLESS it has an address set.
-    // - library blocks are put last.
-    // - blocks are ordered by address, where blocks without address are placed last.
-    // - in every block and module, most directives and vardecls are moved to the top. (not in subroutines!)
-    // - the 'start' subroutine is moved to the top.
-    // - (syntax desugaring) a vardecl with a non-const initializer value is split into a regular vardecl and an assignment statement.
-    // - (syntax desugaring) struct value assignment is expanded into several struct member assignments.
-    // - in-place assignments are reordered a bit so that they are mostly of the form A = A <operator> <rest>
-    // - sorts the choices in when statement.
-    // - insert AddressOf (&) expression where required (string params to a UWORD function param etc).
-
-    private val noModifications = emptyList<IAstModification>()
-    private val directivesToMove = setOf("%output", "%launcher", "%zeropage", "%zpreserved", "%address", "%option")
-
-    override fun after(module: Module, parent: Node): Iterable<IAstModification> {
-        val (blocks, other) = module.statements.partition { it is Block }
-        module.statements = other.asSequence().plus(blocks.sortedBy { (it as Block).address ?: Int.MAX_VALUE }).toMutableList()
-
-        val mainBlock = module.statements.filterIsInstance<Block>().firstOrNull { it.name=="main" }
-        if(mainBlock!=null && mainBlock.address==null) {
-            module.statements.remove(mainBlock)
-            module.statements.add(0, mainBlock)
-        }
-
-        reorderVardeclsAndDirectives(module.statements)
-        return noModifications
-    }
-
-    private fun reorderVardeclsAndDirectives(statements: MutableList<Statement>) {
-        val varDecls = statements.filterIsInstance<VarDecl>()
-        statements.removeAll(varDecls)
-        statements.addAll(0, varDecls)
-
-        val directives = statements.filterIsInstance<Directive>().filter {it.directive in directivesToMove}
-        statements.removeAll(directives)
-        statements.addAll(0, directives)
-    }
-
-    override fun before(block: Block, parent: Node): Iterable<IAstModification> {
-        parent as Module
-        if(block.isInLibrary) {
-            return listOf(
-                    IAstModification.Remove(block, parent),
-                    IAstModification.InsertLast(block, parent)
-            )
-        }
-
-        reorderVardeclsAndDirectives(block.statements)
-        return noModifications
-    }
-
-    override fun before(subroutine: Subroutine, parent: Node): Iterable<IAstModification> {
-        if(subroutine.name=="start" && parent is Block) {
-            if(parent.statements.filterIsInstance<Subroutine>().first().name!="start") {
-                return listOf(
-                        IAstModification.Remove(subroutine, parent),
-                        IAstModification.InsertFirst(subroutine, parent)
-                )
-            }
-        }
-
-        val subs = subroutine.statements.filterIsInstance<Subroutine>()
-        if(subs.isNotEmpty()) {
-            // all subroutines defined within this subroutine are moved to the end
-            return subs.map { IAstModification.Remove(it, subroutine) } +
-                    subs.map { IAstModification.InsertLast(it, subroutine) }
-        }
-
-        return noModifications
-    }
-
-    override fun after(arrayIndexedExpression: ArrayIndexedExpression, parent: Node): Iterable<IAstModification> {
-        when (val expr2 = arrayIndexedExpression.indexer.origExpression) {
-            is NumericLiteralValue -> {
-                arrayIndexedExpression.indexer.indexNum = expr2
-                arrayIndexedExpression.indexer.origExpression = null
-                return noModifications
-            }
-            is IdentifierReference -> {
-                arrayIndexedExpression.indexer.indexVar = expr2
-                arrayIndexedExpression.indexer.origExpression = null
-                return noModifications
-            }
-            is Expression -> {
-                // replace complex indexing with a temp variable
-                return getAutoIndexerVarFor(arrayIndexedExpression)
-            }
-            else -> return noModifications
-        }
-    }
-
-    override fun after(expr: BinaryExpression, parent: Node): Iterable<IAstModification> {
-        // when using a simple bit shift and assigning it to a variable of a different type,
-        // try to make the bit shifting 'wide enough' to fall into the variable's type.
-        // with this, for instance, uword x = 1 << 10  will result in 1024 rather than 0 (the ubyte result).
-        if(expr.operator=="<<" || expr.operator==">>") {
-            val leftDt = expr.left.inferType(program)
-            when (parent) {
-                is Assignment -> {
-                    val targetDt = parent.target.inferType(program)
-                    if(leftDt != targetDt) {
-                        val cast = TypecastExpression(expr.left, targetDt.typeOrElse(DataType.STRUCT), true, parent.position)
-                        return listOf(IAstModification.ReplaceNode(expr.left, cast, expr))
-                    }
-                }
-                is VarDecl -> {
-                    if(!leftDt.istype(parent.datatype)) {
-                        val cast = TypecastExpression(expr.left, parent.datatype, true, parent.position)
-                        return listOf(IAstModification.ReplaceNode(expr.left, cast, expr))
-                    }
-                }
-                is IFunctionCall -> {
-                    val argnum = parent.args.indexOf(expr)
-                    when (val callee = parent.target.targetStatement(program.namespace)) {
-                        is Subroutine -> {
-                            val paramType = callee.parameters[argnum].type
-                            if(leftDt isAssignableTo paramType) {
-                                val cast = TypecastExpression(expr.left, paramType, true, parent.position)
-                                return listOf(IAstModification.ReplaceNode(expr.left, cast, expr))
-                            }
-                        }
-                        is BuiltinFunctionStatementPlaceholder -> {
-                            val func = BuiltinFunctions.getValue(callee.name)
-                            val paramTypes = func.parameters[argnum].possibleDatatypes
-                            for(type in paramTypes) {
-                                if(leftDt isAssignableTo type) {
-                                    val cast = TypecastExpression(expr.left, type, true, parent.position)
-                                    return listOf(IAstModification.ReplaceNode(expr.left, cast, expr))
-                                }
-                            }
-                        }
-                        else -> throw FatalAstException("weird callee")
-                    }
-                }
-                else -> return noModifications
-            }
-        }
-        return noModifications
-    }
-
-    private fun getAutoIndexerVarFor(expr: ArrayIndexedExpression): MutableList<IAstModification> {
-        val modifications = mutableListOf<IAstModification>()
-        val subroutine = expr.definingSubroutine()!!
-        val statement = expr.containingStatement()
-        val indexerVarPrefix = "prog8_autovar_index_"
-        val repo = subroutine.asmGenInfo.usedAutoArrayIndexerForStatements
-
-        // TODO make this a bit smarter so it can reuse indexer variables. BUT BEWARE of scoping+initialization problems then
-        // add another loop index var to be used for this expression
-        val indexerVarName = "$indexerVarPrefix${expr.indexer.hashCode()}"
-        val indexerVar = AsmGenInfo.ArrayIndexerInfo(indexerVarName, expr.indexer)
-        repo.add(indexerVar)
-        // create the indexer var at block level scope
-        val vardecl = VarDecl(VarDeclType.VAR, DataType.UBYTE, ZeropageWish.PREFER_ZEROPAGE,
-                null, indexerVarName, null, null, isArray = false, autogeneratedDontRemove = true, position = expr.position)
-        modifications.add(IAstModification.InsertFirst(vardecl, subroutine))
-
-        // replace the indexer with just the variable
-        // assign the indexing expression to the helper variable, but only if that hasn't been done already
-        val indexerExpression = expr.indexer.origExpression!!
-        val target = AssignTarget(IdentifierReference(listOf(indexerVar.name), indexerExpression.position), null, null, indexerExpression.position)
-        val assign = Assignment(target, indexerExpression, indexerExpression.position)
-        modifications.add(IAstModification.InsertBefore(statement, assign, statement.definingScope()))
-        modifications.add(IAstModification.SetExpression( {
-            expr.indexer.indexVar = it as IdentifierReference
-            expr.indexer.indexNum = null
-            expr.indexer.origExpression = null
-        }, target.identifier!!.copy(), expr.indexer))
-
-        return modifications
-    }
-
-    override fun after(whenStatement: WhenStatement, parent: Node): Iterable<IAstModification> {
-        val choices = whenStatement.choiceValues(program).sortedBy {
-            it.first?.first() ?: Int.MAX_VALUE
-        }
-        whenStatement.choices.clear()
-        choices.mapTo(whenStatement.choices) { it.second }
-        return noModifications
-    }
-
-    override fun after(decl: VarDecl, parent: Node): Iterable<IAstModification> {
-        val declValue = decl.value
-        if(declValue!=null && decl.type== VarDeclType.VAR && decl.datatype in NumericDatatypes) {
-            val declConstValue = declValue.constValue(program)
-            if(declConstValue==null) {
-                // move the vardecl (without value) to the scope and replace this with a regular assignment
-                // Unless we're dealing with a floating point variable because that will actually make things less efficient at the moment (because floats are mostly calcualated via the stack)
-                if(decl.datatype!=DataType.FLOAT) {
-                    decl.value = null
-                    decl.allowInitializeWithZero = false
-                    val target = AssignTarget(IdentifierReference(listOf(decl.name), decl.position), null, null, decl.position)
-                    val assign = Assignment(target, declValue, decl.position)
-                    return listOf(
-                            IAstModification.ReplaceNode(decl, assign, parent),
-                            IAstModification.InsertFirst(decl, decl.definingScope())
-                    )
-                }
-            }
-        }
-        return noModifications
-    }
-
-    override fun before(assignment: Assignment, parent: Node): Iterable<IAstModification> {
-        val valueType = assignment.value.inferType(program)
-        val targetType = assignment.target.inferType(program)
-        var assignments = emptyList<Assignment>()
-
-        if(targetType.istype(DataType.STRUCT) && (valueType.istype(DataType.STRUCT) || valueType.typeOrElse(DataType.STRUCT) in ArrayDatatypes )) {
-            assignments = if (assignment.value is ArrayLiteralValue) {
-                flattenStructAssignmentFromStructLiteral(assignment)    //  'structvar = [ ..... ] '
-            } else {
-                flattenStructAssignmentFromIdentifier(assignment)    //   'structvar1 = structvar2'
-            }
-        }
-
-        if(targetType.typeOrElse(DataType.STRUCT) in ArrayDatatypes && valueType.typeOrElse(DataType.STRUCT) in ArrayDatatypes ) {
-            assignments = if (assignment.value is ArrayLiteralValue) {
-                flattenArrayAssignmentFromArrayLiteral(assignment)    //  'arrayvar = [ ..... ] '
-            } else {
-                flattenArrayAssignmentFromIdentifier(assignment)    //   'arrayvar1 = arrayvar2'
-            }
-        }
-
-        if(assignments.isNotEmpty()) {
-            val modifications = mutableListOf<IAstModification>()
-            val scope = assignment.definingScope()
-            assignments.reversed().mapTo(modifications) { IAstModification.InsertAfter(assignment, it, scope) }
-            modifications.add(IAstModification.Remove(assignment, scope))
-            return modifications
-        }
-
-        return noModifications
-    }
-
-    override fun after(assignment: Assignment, parent: Node): Iterable<IAstModification> {
-        // rewrite in-place assignment expressions a bit so that the assignment target usually is the leftmost operand
-        val binExpr = assignment.value as? BinaryExpression
-        if(binExpr!=null) {
-            if(binExpr.left isSameAs assignment.target) {
-                // A = A <operator> 5, unchanged
-                return noModifications
-            }
-
-            if(binExpr.operator in associativeOperators) {
-                if (binExpr.right isSameAs assignment.target) {
-                    // A = v <associative-operator> A  ==>  A = A <associative-operator> v
-                    return listOf(IAstModification.SwapOperands(binExpr))
-                }
-
-                val leftBinExpr = binExpr.left as? BinaryExpression
-                if(leftBinExpr?.operator == binExpr.operator) {
-                    return if(leftBinExpr.left isSameAs assignment.target) {
-                        // A = (A <associative-operator> x) <same-operator> y ==> A = A <associative-operator> (x <same-operator> y)
-                        val newRight = BinaryExpression(leftBinExpr.right, binExpr.operator, binExpr.right, binExpr.position)
-                        val newValue = BinaryExpression(leftBinExpr.left, binExpr.operator, newRight, binExpr.position)
-                        listOf(IAstModification.ReplaceNode(binExpr, newValue, assignment))
-                    } else {
-                        // A = (x <associative-operator> A) <same-operator> y ==> A = A <associative-operator> (x <same-operator> y)
-                        val newRight = BinaryExpression(leftBinExpr.left, binExpr.operator, binExpr.right, binExpr.position)
-                        val newValue = BinaryExpression(leftBinExpr.right, binExpr.operator, newRight, binExpr.position)
-                        listOf(IAstModification.ReplaceNode(binExpr, newValue, assignment))
-                    }
-                }
-                val rightBinExpr = binExpr.right as? BinaryExpression
-                if(rightBinExpr?.operator == binExpr.operator) {
-                    return if(rightBinExpr.left isSameAs assignment.target) {
-                        // A = x <associative-operator> (A <same-operator> y) ==> A = A <associative-operator> (x <same-operator> y)
-                        val newRight = BinaryExpression(binExpr.left, binExpr.operator, rightBinExpr.right, binExpr.position)
-                        val newValue = BinaryExpression(rightBinExpr.left, binExpr.operator, newRight, binExpr.position)
-                        listOf(IAstModification.ReplaceNode(binExpr, newValue, assignment))
-                    } else {
-                        // A = x <associative-operator> (y <same-operator> A) ==> A = A <associative-operator> (x <same-operator> y)
-                        val newRight = BinaryExpression(binExpr.left, binExpr.operator, rightBinExpr.left, binExpr.position)
-                        val newValue = BinaryExpression(rightBinExpr.right, binExpr.operator, newRight, binExpr.position)
-                        listOf(IAstModification.ReplaceNode(binExpr, newValue, assignment))
-                    }
-                }
-            }
-        }
-
-        return noModifications
-    }
-
-    private fun flattenArrayAssignmentFromArrayLiteral(assign: Assignment): List<Assignment> {
-        val identifier = assign.target.identifier!!
-        val targetVar = identifier.targetVarDecl(program.namespace)!!
-        val alv = assign.value as? ArrayLiteralValue
-        return flattenArrayAssign(targetVar, alv, identifier, assign.position)
-    }
-
-    private fun flattenArrayAssignmentFromIdentifier(assign: Assignment): List<Assignment> {
-        val identifier = assign.target.identifier!!
-        val targetVar = identifier.targetVarDecl(program.namespace)!!
-        val sourceIdent = assign.value as IdentifierReference
-        val sourceVar = sourceIdent.targetVarDecl(program.namespace)!!
-        if(!sourceVar.isArray) {
-            errors.err("value must be an array",  sourceIdent.position)
-            return emptyList()
-        }
-        val alv = sourceVar.value as? ArrayLiteralValue
-        return flattenArrayAssign(targetVar, alv, identifier, assign.position)
-    }
-
-    private fun flattenArrayAssign(targetVar: VarDecl, alv: ArrayLiteralValue?, identifier: IdentifierReference, position: Position): List<Assignment> {
-        if(targetVar.arraysize==null) {
-            errors.err("array has no defined size", identifier.position)
-            return emptyList()
-        }
-
-        if(alv==null || alv.value.size != targetVar.arraysize!!.constIndex()) {
-            errors.err("element count mismatch", position)
-            return emptyList()
-        }
-
-        // TODO use a pointer loop instead of individual assignments
-        return alv.value.mapIndexed { index, value ->
-            val idx = ArrayIndexedExpression(identifier, ArrayIndex(NumericLiteralValue(DataType.UBYTE, index, position), position), position)
-            Assignment(AssignTarget(null, idx, null, position), value, value.position)
-        }
-    }
-
-    private fun flattenStructAssignmentFromStructLiteral(structAssignment: Assignment): List<Assignment> {
-        val identifier = structAssignment.target.identifier!!
-        val identifierName = identifier.nameInSource.single()
-        val targetVar = identifier.targetVarDecl(program.namespace)!!
-        val struct = targetVar.struct!!
-
-        val slv = structAssignment.value as? ArrayLiteralValue
-        if(slv==null || slv.value.size != struct.numberOfElements) {
-            errors.err("element count mismatch", structAssignment.position)
-            return emptyList()
-        }
-
-        return struct.statements.zip(slv.value).map { (targetDecl, sourceValue) ->
-            targetDecl as VarDecl
-            val mangled = mangledStructMemberName(identifierName, targetDecl.name)
-            val idref = IdentifierReference(listOf(mangled), structAssignment.position)
-            val assign = Assignment(AssignTarget(idref, null, null, structAssignment.position),
-                    sourceValue, sourceValue.position)
-            assign.linkParents(structAssignment)
-            assign
-        }
-    }
-
-    private fun flattenStructAssignmentFromIdentifier(structAssignment: Assignment): List<Assignment> {
-        // TODO use memcopy beyond a certain number of elements
-        val identifier = structAssignment.target.identifier!!
-        val identifierName = identifier.nameInSource.single()
-        val targetVar = identifier.targetVarDecl(program.namespace)!!
-        val struct = targetVar.struct!!
-        when (structAssignment.value) {
-            is IdentifierReference -> {
-                val sourceVar = (structAssignment.value as IdentifierReference).targetVarDecl(program.namespace)!!
-                when {
-                    sourceVar.struct!=null -> {
-                        // struct memberwise copy
-                        val sourceStruct = sourceVar.struct!!
-                        if(sourceStruct!==targetVar.struct) {
-                            // structs are not the same in assignment
-                            return listOf()     // error will be printed elsewhere
-                        }
-                        if(struct.statements.size!=sourceStruct.statements.size)
-                            return listOf()     // error will be printed elsewhere
-                        return struct.statements.zip(sourceStruct.statements).map { member ->
-                            val targetDecl = member.first as VarDecl
-                            val sourceDecl = member.second as VarDecl
-                            if(targetDecl.name != sourceDecl.name)
-                                throw FatalAstException("struct member mismatch")
-                            val mangled = mangledStructMemberName(identifierName, targetDecl.name)
-                            val idref = IdentifierReference(listOf(mangled), structAssignment.position)
-                            val sourcemangled = mangledStructMemberName(sourceVar.name, sourceDecl.name)
-                            val sourceIdref = IdentifierReference(listOf(sourcemangled), structAssignment.position)
-                            val assign = Assignment(AssignTarget(idref, null, null, structAssignment.position), sourceIdref, member.second.position)
-                            assign.linkParents(structAssignment)
-                            assign
-                        }
-                    }
-                    sourceVar.isArray -> {
-                        val array = (sourceVar.value as ArrayLiteralValue).value
-                        if(struct.statements.size!=array.size)
-                            return listOf()     // error will be printed elsewhere
-                        return struct.statements.zip(array).map {
-                            val decl = it.first as VarDecl
-                            val mangled = mangledStructMemberName(identifierName, decl.name)
-                            val targetName = IdentifierReference(listOf(mangled), structAssignment.position)
-                            val target = AssignTarget(targetName, null, null, structAssignment.position)
-                            val assign = Assignment(target, it.second, structAssignment.position)
-                            assign.linkParents(structAssignment)
-                            assign
-                        }
-                    }
-                    else -> {
-                        throw FatalAstException("can only assign arrays or structs to structs")
-                    }
-                }
-            }
-            is ArrayLiteralValue -> {
-                throw IllegalArgumentException("not going to flatten a structLv assignment here")
-            }
-            else -> throw FatalAstException("strange struct value")
-        }
-    }
-
-}

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

@@ -1,44 +0,0 @@
-package prog8.ast.processing
-
-import prog8.ast.INameScope
-import prog8.ast.Node
-import prog8.ast.expressions.NumericLiteralValue
-import prog8.ast.expressions.TypecastExpression
-import prog8.ast.statements.AnonymousScope
-import prog8.ast.statements.NopStatement
-
-
-internal class VariousCleanups: AstWalker() {
-    private val noModifications = emptyList<IAstModification>()
-
-    override fun before(nopStatement: NopStatement, parent: Node): Iterable<IAstModification> {
-        return listOf(IAstModification.Remove(nopStatement, parent as INameScope))
-    }
-
-    override fun before(scope: AnonymousScope, parent: Node): Iterable<IAstModification> {
-        return if(parent is INameScope)
-            listOf(ScopeFlatten(scope, parent as INameScope))
-        else
-            noModifications
-    }
-
-    class ScopeFlatten(val scope: AnonymousScope, val into: INameScope) : IAstModification {
-        override fun perform() {
-            val idx = into.statements.indexOf(scope)
-            if(idx>=0) {
-                into.statements.addAll(idx+1, scope.statements)
-                into.statements.remove(scope)
-            }
-        }
-    }
-
-    override fun before(typecast: TypecastExpression, parent: Node): Iterable<IAstModification> {
-        if(typecast.expression is NumericLiteralValue) {
-            val value = (typecast.expression as NumericLiteralValue).cast(typecast.type)
-            if(value.isValid)
-                return listOf(IAstModification.ReplaceNode(typecast, value.valueOrZero(), parent))
-        }
-
-        return noModifications
-    }
-}

compiler/src/prog8/compiler/AssemblyError.kt

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