fix partial unused code removal in vm target

preparing 11.4

.github/FUNDING.yml

@@ -0,0 +1,14 @@
+# These are supported funding model platforms
+
+#github: # Replace with up to 4 GitHub Sponsors-enabled usernames e.g., [user1, user2]
+#patreon: # Replace with a single Patreon username
+#open_collective: # Replace with a single Open Collective username
+ko_fi: irmen
+#tidelift: # Replace with a single Tidelift platform-name/package-name e.g., npm/babel
+#community_bridge: # Replace with a single Community Bridge project-name e.g., cloud-foundry
+#liberapay: # Replace with a single Liberapay username
+#issuehunt: # Replace with a single IssueHunt username
+#otechie: # Replace with a single Otechie username
+#lfx_crowdfunding: # Replace with a single LFX Crowdfunding project-name e.g., cloud-foundry
+#custom: # Replace with up to 4 custom sponsorship URLs e.g., ['link1', 'link2']
+custom: ['https://paypal.me/irmendejong']

.github/workflows/all-ci.yml

@@ -0,0 +1,41 @@
+name: Build and Test the Prog8 compiler
+
+on:
+  push:
+  workflow_dispatch:
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+
+      - name: build and install recent 64tass
+        run: |
+          sudo apt-get install -y make build-essential
+          git clone --depth=1 https://github.com/irmen/64tass
+          cd 64tass
+          make -j4
+          sudo make install          
+
+      - name: Set up JDK 11
+        uses: actions/setup-java@v4
+        with:
+          java-version: 11
+          distribution: temurin
+
+      - name: Build and test with Gradle
+        run: |
+          ./gradlew build shadowJar --no-daemon
+          sha256sum -b compiler/build/libs/*-all.jar > compiler/build/libs/hash.txt
+        
+      - name: Create compiler shadowJar artifact
+        uses: actions/upload-artifact@v4
+        with:
+          name: prog8-compiler-jar-zipped
+          path: |
+            compiler/build/libs/*-all.jar
+            compiler/build/libs/hash.txt
+

.gitignore

@@ -1,8 +1,12 @@
 .idea/workspace.xml
 .idea/discord.xml
+.idea/developer-tools.xml
+.idea/usage.statistics.xml
+.idea/shelf/
 build/
 dist/
 output/
+out/
 .*cache/
 *.directory
 *.prg
@@ -11,16 +15,17 @@ output/
 *.vm.txt
 *.vice-mon-list
 docs/build
-out/
 parser/**/*.interp
 parser/**/*.tokens
 parser/**/*.java
+compiler/src/prog8/buildversion/*
 *.py[cod]
 *.egg
 *.egg-info
 .eggs/
 /MANIFEST
 .tox/
+.kotlin/
 __pycache__/
 parser.out
 parsetab.py
@@ -29,6 +34,6 @@ parsetab.py
 compiler/lib/
 
 .gradle
-/prog8compiler.jar
 sd*.img
 *.d64
+

.idea/compiler.xml

@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project version="4">
   <component name="CompilerConfiguration">
-    <option name="BUILD_PROCESS_HEAP_SIZE" value="1200" />
+    <option name="BUILD_PROCESS_HEAP_SIZE" value="3000" />
     <bytecodeTargetLevel target="11" />
   </component>
-</project>
+</project>

.idea/kotlinc.xml

@@ -1,6 +1,19 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project version="4">
+  <component name="Kotlin2JsCompilerArguments">
+    <option name="moduleKind" value="plain" />
+  </component>
   <component name="Kotlin2JvmCompilerArguments">
     <option name="jvmTarget" value="11" />
   </component>
+  <component name="KotlinCommonCompilerArguments">
+    <option name="apiVersion" value="2.1" />
+    <option name="languageVersion" value="2.1" />
+  </component>
+  <component name="KotlinCompilerSettings">
+    <option name="additionalArguments" value="-Xwhen-guards" />
+  </component>
+  <component name="KotlinJpsPluginSettings">
+    <option name="version" value="2.1.10" />
+  </component>
 </project>

.idea/libraries/KotlinJavaRuntime.xml

@@ -1,19 +1,23 @@
 <component name="libraryTable">
-  <library name="KotlinJavaRuntime">
+  <library name="KotlinJavaRuntime" type="repository">
+    <properties maven-id="org.jetbrains.kotlin:kotlin-stdlib-jdk8:2.1.20" />
     <CLASSES>
-      <root url="jar://$KOTLIN_BUNDLED$/lib/kotlin-stdlib.jar!/" />
-      <root url="jar://$KOTLIN_BUNDLED$/lib/kotlin-reflect.jar!/" />
-      <root url="jar://$KOTLIN_BUNDLED$/lib/kotlin-test.jar!/" />
-      <root url="jar://$KOTLIN_BUNDLED$/lib/kotlin-stdlib-jdk7.jar!/" />
-      <root url="jar://$KOTLIN_BUNDLED$/lib/kotlin-stdlib-jdk8.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk8/2.1.20/kotlin-stdlib-jdk8-2.1.20.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/2.1.20/kotlin-stdlib-2.1.20.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-jdk7/2.1.20/kotlin-stdlib-jdk7-2.1.20.jar!/" />
     </CLASSES>
-    <JAVADOC />
+    <JAVADOC>
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk8/2.1.20/kotlin-stdlib-jdk8-2.1.20-javadoc.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/2.1.20/kotlin-stdlib-2.1.20-javadoc.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/annotations/13.0/annotations-13.0-javadoc.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk7/2.1.20/kotlin-stdlib-jdk7-2.1.20-javadoc.jar!/" />
+    </JAVADOC>
     <SOURCES>
-      <root url="jar://$KOTLIN_BUNDLED$/lib/kotlin-stdlib-sources.jar!/" />
-      <root url="jar://$KOTLIN_BUNDLED$/lib/kotlin-reflect-sources.jar!/" />
-      <root url="jar://$KOTLIN_BUNDLED$/lib/kotlin-test-sources.jar!/" />
-      <root url="jar://$KOTLIN_BUNDLED$/lib/kotlin-stdlib-jdk7-sources.jar!/" />
-      <root url="jar://$KOTLIN_BUNDLED$/lib/kotlin-stdlib-jdk8-sources.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk8/2.1.20/kotlin-stdlib-jdk8-2.1.20-sources.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/2.1.20/kotlin-stdlib-2.1.20-sources.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/annotations/13.0/annotations-13.0-sources.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk7/2.1.20/kotlin-stdlib-jdk7-2.1.20-sources.jar!/" />
     </SOURCES>
   </library>
 </component>

.idea/libraries/antlr_antlr4.xml

@@ -1,17 +1,16 @@
 <component name="libraryTable">
   <library name="antlr.antlr4" type="repository">
-    <properties maven-id="org.antlr:antlr4:4.9.2">
+    <properties maven-id="org.antlr:antlr4:4.13.2">
       <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/antlr/antlr4/4.13.2/antlr4-4.13.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/antlr/antlr4-runtime/4.13.2/antlr4-runtime-4.13.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/antlr/antlr-runtime/3.5.3/antlr-runtime-3.5.3.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/antlr/ST4/4.3.4/ST4-4.3.4.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/abego/treelayout/org.abego.treelayout.core/1.0.3/org.abego.treelayout.core-1.0.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/glassfish/javax.json/1.0.4/javax.json-1.0.4.jar!/" />
     </CLASSES>
     <JAVADOC />
     <SOURCES />

.idea/libraries/eclipse_lsp4j.xml

@@ -0,0 +1,13 @@
+<component name="libraryTable">
+  <library name="eclipse.lsp4j" type="repository">
+    <properties maven-id="org.eclipse.lsp4j:org.eclipse.lsp4j:0.24.0" />
+    <CLASSES>
+      <root url="jar://$MAVEN_REPOSITORY$/org/eclipse/lsp4j/org.eclipse.lsp4j/0.24.0/org.eclipse.lsp4j-0.24.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/eclipse/lsp4j/org.eclipse.lsp4j.jsonrpc/0.24.0/org.eclipse.lsp4j.jsonrpc-0.24.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/com/google/code/gson/gson/2.12.1/gson-2.12.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/com/google/errorprone/error_prone_annotations/2.36.0/error_prone_annotations-2.36.0.jar!/" />
+    </CLASSES>
+    <JAVADOC />
+    <SOURCES />
+  </library>
+</component>

.idea/libraries/github_hypfvieh_dbus_java.xml

@@ -1,25 +0,0 @@
-<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

@@ -1,10 +0,0 @@
-<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/io_kotest_assertions_core_jvm.xml

@@ -1,20 +1,18 @@
 <component name="libraryTable">
   <library name="io.kotest.assertions.core.jvm" type="repository">
-    <properties maven-id="io.kotest:kotest-assertions-core-jvm:4.6.3" />
+    <properties maven-id="io.kotest:kotest-assertions-core-jvm:5.9.1" />
     <CLASSES>
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-core-jvm/4.6.3/kotest-assertions-core-jvm-4.6.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk8/1.5.0/kotlin-stdlib-jdk8-1.5.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/1.5.0/kotlin-stdlib-1.5.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-core-jvm/5.9.1/kotest-assertions-core-jvm-5.9.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-shared-jvm/5.9.1/kotest-assertions-shared-jvm-5.9.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/github/java-diff-utils/java-diff-utils/4.12/java-diff-utils-4.12.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/opentest4j/opentest4j/1.3.0/opentest4j-1.3.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/1.9.23/kotlin-stdlib-1.9.23.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-jdk7/1.5.0/kotlin-stdlib-jdk7-1.5.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-shared-jvm/4.6.3/kotest-assertions-shared-jvm-4.6.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/github/java-diff-utils/java-diff-utils/4.9/java-diff-utils-4.9.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-jdk8/1.5.0/kotlinx-coroutines-jdk8-1.5.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-reflect/1.5.0/kotlin-reflect-1.5.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-core-jvm/1.5.0/kotlinx-coroutines-core-jvm-1.5.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-common/1.5.0/kotlin-stdlib-common-1.5.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-common-jvm/4.6.3/kotest-common-jvm-4.6.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-api-jvm/4.6.3/kotest-assertions-api-jvm-4.6.3.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-jdk8/1.8.0/kotlinx-coroutines-jdk8-1.8.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-reflect/1.9.23/kotlin-reflect-1.9.23.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-common-jvm/5.9.1/kotest-common-jvm-5.9.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-api-jvm/5.9.1/kotest-assertions-api-jvm-5.9.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-core-jvm/1.8.0/kotlinx-coroutines-core-jvm-1.8.0.jar!/" />
     </CLASSES>
     <JAVADOC />
     <SOURCES />

.idea/libraries/io_kotest_framework_datatest.xml

@@ -0,0 +1,23 @@
+<component name="libraryTable">
+  <library name="io.kotest.framework.datatest" type="repository">
+    <properties maven-id="io.kotest:kotest-framework-datatest:5.9.1" />
+    <CLASSES>
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-framework-datatest/5.9.1/kotest-framework-datatest-5.9.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-framework-datatest-jvm/5.9.1/kotest-framework-datatest-jvm-5.9.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/1.9.23/kotlin-stdlib-1.9.23.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/annotations/13.0/annotations-13.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-core-jvm/1.8.0/kotlinx-coroutines-core-jvm-1.8.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-common-jvm/5.9.1/kotest-common-jvm-5.9.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-reflect/1.9.23/kotlin-reflect-1.9.23.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-framework-api-jvm/5.9.1/kotest-framework-api-jvm-5.9.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-shared-jvm/5.9.1/kotest-assertions-shared-jvm-5.9.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-api-jvm/5.9.1/kotest-assertions-api-jvm-5.9.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-jdk8/1.8.0/kotlinx-coroutines-jdk8-1.8.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/github/java-diff-utils/java-diff-utils/4.12/java-diff-utils-4.12.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/opentest4j/opentest4j/1.3.0/opentest4j-1.3.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-test-jvm/1.8.0/kotlinx-coroutines-test-jvm-1.8.0.jar!/" />
+    </CLASSES>
+    <JAVADOC />
+    <SOURCES />
+  </library>
+</component>

.idea/libraries/io_kotest_property_jvm.xml

@@ -1,24 +0,0 @@
-<component name="libraryTable">
-  <library name="io.kotest.property.jvm" type="repository">
-    <properties maven-id="io.kotest:kotest-property-jvm:4.6.3" />
-    <CLASSES>
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-property-jvm/4.6.3/kotest-property-jvm-4.6.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk8/1.5.0/kotlin-stdlib-jdk8-1.5.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/1.5.0/kotlin-stdlib-1.5.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/annotations/13.0/annotations-13.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk7/1.5.0/kotlin-stdlib-jdk7-1.5.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-common-jvm/4.6.3/kotest-common-jvm-4.6.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-shared-jvm/4.6.3/kotest-assertions-shared-jvm-4.6.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-api-jvm/4.6.3/kotest-assertions-api-jvm-4.6.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-jdk8/1.5.0/kotlinx-coroutines-jdk8-1.5.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/github/java-diff-utils/java-diff-utils/4.9/java-diff-utils-4.9.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/com/github/mifmif/generex/1.0.2/generex-1.0.2.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/dk/brics/automaton/automaton/1.11-8/automaton-1.11-8.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-reflect/1.5.0/kotlin-reflect-1.5.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-core-jvm/1.5.0/kotlinx-coroutines-core-jvm-1.5.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-common/1.5.0/kotlin-stdlib-common-1.5.0.jar!/" />
-    </CLASSES>
-    <JAVADOC />
-    <SOURCES />
-  </library>
-</component>

.idea/libraries/io_kotest_runner_junit5_jvm.xml

@@ -1,54 +1,39 @@
 <component name="libraryTable">
   <library name="io.kotest.runner.junit5.jvm" type="repository">
-    <properties maven-id="io.kotest:kotest-runner-junit5-jvm:4.6.3" />
+    <properties maven-id="io.kotest:kotest-runner-junit5-jvm:5.9.1" />
     <CLASSES>
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-runner-junit5-jvm/4.6.3/kotest-runner-junit5-jvm-4.6.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-framework-api-jvm/4.6.3/kotest-framework-api-jvm-4.6.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-shared-jvm/4.6.3/kotest-assertions-shared-jvm-4.6.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/github/java-diff-utils/java-diff-utils/4.9/java-diff-utils-4.9.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-common-jvm/4.6.3/kotest-common-jvm-4.6.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-framework-engine-jvm/4.6.3/kotest-framework-engine-jvm-4.6.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/github/classgraph/classgraph/4.8.105/classgraph-4.8.105.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-runner-junit5-jvm/5.9.1/kotest-runner-junit5-jvm-5.9.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-framework-api-jvm/5.9.1/kotest-framework-api-jvm-5.9.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-shared-jvm/5.9.1/kotest-assertions-shared-jvm-5.9.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/github/java-diff-utils/java-diff-utils/4.12/java-diff-utils-4.12.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-test-jvm/1.8.0/kotlinx-coroutines-test-jvm-1.8.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-common-jvm/5.9.1/kotest-common-jvm-5.9.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-framework-engine-jvm/5.9.1/kotest-framework-engine-jvm-5.9.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/github/classgraph/classgraph/4.8.172/classgraph-4.8.172.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/com/github/ajalt/mordant/1.2.1/mordant-1.2.1.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/com/github/ajalt/colormath/1.2.0/colormath-1.2.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-script-util/1.5.0/kotlin-script-util-1.5.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/intellij/deps/trove4j/1.0.20181211/trove4j-1.0.20181211.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-daemon-client/1.5.0/kotlin-daemon-client-1.5.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-core/1.3.8/kotlinx-coroutines-core-1.3.8.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-scripting-jvm/1.5.0/kotlin-scripting-jvm-1.5.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-scripting-common/1.5.0/kotlin-scripting-common-1.5.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/opentest4j/opentest4j/1.2.0/opentest4j-1.2.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-framework-discovery-jvm/4.6.3/kotest-framework-discovery-jvm-4.6.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-core-jvm/4.6.3/kotest-assertions-core-jvm-4.6.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-jdk8/1.5.0/kotlinx-coroutines-jdk8-1.5.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-api-jvm/4.6.3/kotest-assertions-api-jvm-4.6.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-extensions-jvm/4.6.3/kotest-extensions-jvm-4.6.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/commons-io/commons-io/2.6/commons-io-2.6.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/mockk/mockk/1.9.3/mockk-1.9.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/mockk/mockk-common/1.9.3/mockk-common-1.9.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/mockk/mockk-dsl/1.9.3/mockk-dsl-1.9.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/mockk/mockk-dsl-jvm/1.9.3/mockk-dsl-jvm-1.9.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/mockk/mockk-agent-jvm/1.9.3/mockk-agent-jvm-1.9.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/mockk/mockk-agent-api/1.9.3/mockk-agent-api-1.9.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/mockk/mockk-agent-common/1.9.3/mockk-agent-common-1.9.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/objenesis/objenesis/3.0.1/objenesis-3.0.1.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/net/bytebuddy/byte-buddy/1.9.10/byte-buddy-1.9.10.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/net/bytebuddy/byte-buddy-agent/1.9.10/byte-buddy-agent-1.9.10.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-framework-concurrency-jvm/4.6.3/kotest-framework-concurrency-jvm-4.6.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-core-jvm/1.5.0/kotlinx-coroutines-core-jvm-1.5.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-common/1.5.0/kotlin-stdlib-common-1.5.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/junit/platform/junit-platform-engine/1.6.2/junit-platform-engine-1.6.2.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/junit/platform/junit-platform-commons/1.6.2/junit-platform-commons-1.6.2.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/junit/platform/junit-platform-suite-api/1.6.2/junit-platform-suite-api-1.6.2.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/junit/platform/junit-platform-launcher/1.6.2/junit-platform-launcher-1.6.2.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/junit/jupiter/junit-jupiter-api/5.6.2/junit-jupiter-api-5.6.2.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk8/1.5.0/kotlin-stdlib-jdk8-1.5.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/1.5.0/kotlin-stdlib-1.5.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/annotations/13.0/annotations-13.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk7/1.5.0/kotlin-stdlib-jdk7-1.5.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-script-runtime/1.5.0/kotlin-script-runtime-1.5.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-reflect/1.5.0/kotlin-reflect-1.5.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/opentest4j/opentest4j/1.3.0/opentest4j-1.3.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-debug/1.8.0/kotlinx-coroutines-debug-1.8.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/net/java/dev/jna/jna/5.9.0/jna-5.9.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/net/java/dev/jna/jna-platform/5.9.0/jna-platform-5.9.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/net/bytebuddy/byte-buddy/1.10.9/byte-buddy-1.10.9.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/net/bytebuddy/byte-buddy-agent/1.10.9/byte-buddy-agent-1.10.9.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-framework-discovery-jvm/5.9.1/kotest-framework-discovery-jvm-5.9.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-core-jvm/5.9.1/kotest-assertions-core-jvm-5.9.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-jdk8/1.8.0/kotlinx-coroutines-jdk8-1.8.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-api-jvm/5.9.1/kotest-assertions-api-jvm-5.9.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-extensions-jvm/5.9.1/kotest-extensions-jvm-5.9.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-framework-concurrency-jvm/5.9.1/kotest-framework-concurrency-jvm-5.9.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-core-jvm/1.8.0/kotlinx-coroutines-core-jvm-1.8.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/annotations/23.0.0/annotations-23.0.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/junit/platform/junit-platform-engine/1.8.2/junit-platform-engine-1.8.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/junit/platform/junit-platform-commons/1.8.2/junit-platform-commons-1.8.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/apiguardian/apiguardian-api/1.1.2/apiguardian-api-1.1.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/junit/platform/junit-platform-suite-api/1.8.2/junit-platform-suite-api-1.8.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/junit/platform/junit-platform-launcher/1.8.2/junit-platform-launcher-1.8.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/junit/jupiter/junit-jupiter-api/5.8.2/junit-jupiter-api-5.8.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/1.9.23/kotlin-stdlib-1.9.23.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-reflect/1.9.23/kotlin-reflect-1.9.23.jar!/" />
     </CLASSES>
     <JAVADOC />
     <SOURCES />

.idea/libraries/jetbrains_kotlinx_cli_jvm.xml

@@ -1,8 +1,8 @@
 <component name="libraryTable">
   <library name="jetbrains.kotlinx.cli.jvm" type="repository">
-    <properties include-transitive-deps="false" maven-id="org.jetbrains.kotlinx:kotlinx-cli-jvm:0.3.3" />
+    <properties include-transitive-deps="false" maven-id="org.jetbrains.kotlinx:kotlinx-cli-jvm:0.3.6" />
     <CLASSES>
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-cli-jvm/0.3.3/kotlinx-cli-jvm-0.3.3.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-cli-jvm/0.3.6/kotlinx-cli-jvm-0.3.6.jar!/" />
     </CLASSES>
     <JAVADOC />
     <SOURCES />

.idea/libraries/michael_bull_kotlin_result_jvm.xml

@@ -1,15 +1,20 @@
 <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" />
+    <properties maven-id="com.michael-bull.kotlin-result:kotlin-result-jvm:2.0.1" />
     <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://$MAVEN_REPOSITORY$/com/michael-bull/kotlin-result/kotlin-result-jvm/2.0.1/kotlin-result-jvm-2.0.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/1.9.22/kotlin-stdlib-1.9.22.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 />
+    <JAVADOC>
+      <root url="jar://$MAVEN_REPOSITORY$/com/michael-bull/kotlin-result/kotlin-result-jvm/2.0.1/kotlin-result-jvm-2.0.1-javadoc.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/1.9.22/kotlin-stdlib-1.9.22-javadoc.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/annotations/13.0/annotations-13.0-javadoc.jar!/" />
+    </JAVADOC>
+    <SOURCES>
+      <root url="jar://$MAVEN_REPOSITORY$/com/michael-bull/kotlin-result/kotlin-result-jvm/2.0.1/kotlin-result-jvm-2.0.1-sources.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/1.9.22/kotlin-stdlib-1.9.22-sources.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/annotations/13.0/annotations-13.0-sources.jar!/" />
+    </SOURCES>
   </library>
 </component>

.idea/libraries/slf4j_simple.xml

@@ -1,11 +0,0 @@
-<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

@@ -1,13 +0,0 @@
-<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/misc.xml

@@ -4,22 +4,26 @@
     <option name="perGrammarGenerationSettings">
       <list>
         <PerGrammarGenerationSettings>
-          <option name="fileName" value="$PROJECT_DIR$/parser/antlr/Prog8ANTLR.g4" />
+          <option name="fileName" value="$PROJECT_DIR$/parser/src/main/antlr/Prog8ANTLR.g4" />
           <option name="autoGen" value="true" />
           <option name="outputDir" value="$PROJECT_DIR$/parser/src/prog8/parser" />
           <option name="libDir" value="" />
           <option name="encoding" value="" />
           <option name="pkg" value="" />
-          <option name="language" value="" />
+          <option name="language" value="Java" />
           <option name="generateListener" value="false" />
+          <option name="generateVisitor" value="true" />
         </PerGrammarGenerationSettings>
       </list>
     </option>
   </component>
+  <component name="Black">
+    <option name="sdkName" value="Python 3.11" />
+  </component>
   <component name="FrameworkDetectionExcludesConfiguration">
     <type id="Python" />
   </component>
-  <component name="ProjectRootManager" version="2" languageLevel="JDK_11" project-jdk-name="11" project-jdk-type="JavaSDK">
+  <component name="ProjectRootManager" version="2" languageLevel="JDK_21" default="true" project-jdk-name="openjdk-21" project-jdk-type="JavaSDK">
     <output url="file://$PROJECT_DIR$/out" />
   </component>
 </project>

.idea/modules.xml

@@ -2,16 +2,23 @@
 <project version="4">
   <component name="ProjectModuleManager">
     <modules>
-      <module fileurl="file://$PROJECT_DIR$/codeGeneration/codeGeneration.iml" filepath="$PROJECT_DIR$/codeGeneration/codeGeneration.iml" />
+      <module fileurl="file://$PROJECT_DIR$/beanshell/beanshell.iml" filepath="$PROJECT_DIR$/beanshell/beanshell.iml" />
+      <module fileurl="file://$PROJECT_DIR$/benchmark-program/benchmark-program.iml" filepath="$PROJECT_DIR$/benchmark-program/benchmark-program.iml" />
+      <module fileurl="file://$PROJECT_DIR$/codeCore/codeCore.iml" filepath="$PROJECT_DIR$/codeCore/codeCore.iml" />
+      <module fileurl="file://$PROJECT_DIR$/codeGenCpu6502/codeGenCpu6502.iml" filepath="$PROJECT_DIR$/codeGenCpu6502/codeGenCpu6502.iml" />
+      <module fileurl="file://$PROJECT_DIR$/codeGenExperimental/codeGenExperimental.iml" filepath="$PROJECT_DIR$/codeGenExperimental/codeGenExperimental.iml" />
+      <module fileurl="file://$PROJECT_DIR$/codeGenIntermediate/codeGenIntermediate.iml" filepath="$PROJECT_DIR$/codeGenIntermediate/codeGenIntermediate.iml" />
+      <module fileurl="file://$PROJECT_DIR$/codeGenVirtual/codeGenVirtual.iml" filepath="$PROJECT_DIR$/codeGenVirtual/codeGenVirtual.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" />
-      <module fileurl="file://$PROJECT_DIR$/httpCompilerService/httpCompilerService.iml" filepath="$PROJECT_DIR$/httpCompilerService/httpCompilerService.iml" />
+      <module fileurl="file://$PROJECT_DIR$/intermediate/intermediate.iml" filepath="$PROJECT_DIR$/intermediate/intermediate.iml" />
       <module fileurl="file://$PROJECT_DIR$/parser/parser.iml" filepath="$PROJECT_DIR$/parser/parser.iml" />
+      <module fileurl="file://$PROJECT_DIR$/.idea/modules/prog8.iml" filepath="$PROJECT_DIR$/.idea/modules/prog8.iml" />
+      <module fileurl="file://$PROJECT_DIR$/simpleAst/simpleAst.iml" filepath="$PROJECT_DIR$/simpleAst/simpleAst.iml" />
+      <module fileurl="file://$PROJECT_DIR$/virtualmachine/virtualmachine.iml" filepath="$PROJECT_DIR$/virtualmachine/virtualmachine.iml" />
     </modules>
   </component>
 </project>

.idea/vcs.xml

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

.readthedocs.yaml

@@ -7,23 +7,21 @@ version: 2
 
 # Set the version of Python and other tools you might need
 build:
-  os: ubuntu-20.04
+  os: ubuntu-22.04
   tools:
-    python: "3.9"
-    # You can also specify other tool versions:
-    # nodejs: "16"
-    # rust: "1.55"
-    # golang: "1.17"
-
-# Build documentation in the docs/ directory with Sphinx
-sphinx:
-  configuration: docs/source/conf.py
-
-# If using Sphinx, optionally build your docs in additional formats such as PDF
-formats:
-  - pdf
+    python: "3.12"
 
 # Optionally declare the Python requirements required to build your docs
 python:
   install:
     - requirements: docs/requirements.txt
+
+# Build documentation in the docs/ directory with Sphinx
+sphinx:
+  configuration: docs/source/conf.py
+  fail_on_warning: true
+
+# If using Sphinx, optionally build your docs in additional formats such as PDF
+formats:
+  - pdf
+  - epub

CompilerDevelopment.md

@@ -1,32 +0,0 @@
-#### 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

@@ -1,6 +1,9 @@
 
-This sofware license is for Prog8 the compiler + associated libraries.
-The software generated by running the compiler is excluded from this.
+This sofware license is for Prog8 the compiler + associated library files.
+
+Exception: All output files generated by the compiler (intermediary files
+and compiled binary programs) are excluded from this; you can do with those
+whatever you want.
 
 
 

Makefile

@@ -0,0 +1,12 @@
+# super simple Makefile to lauch the main gradle targets to build and/or test the prog8 compiler
+
+.PHONY: all test
+
+all:
+	gradle installdist installshadowdist
+	@echo "compiler launch script can be found here: compiler/build/install/compiler-shadow/bin/prog8c"
+
+test:
+	gradle build
+	@echo "compiler launch script can be found here: compiler/build/install/compiler-shadow/bin/prog8c"
+

README.md

@@ -1,3 +1,7 @@
+[![ko-fi](https://ko-fi.com/img/githubbutton_sm.svg)](https://ko-fi.com/H2H6S0FFF)
+
+PayPal: [![PayPal](https://www.paypalobjects.com/en_US/i/btn/btn_donate_LG.gif)](https://paypal.me/irmendejong)
+
 [![Documentation](https://readthedocs.org/projects/prog8/badge/?version=latest)](https://prog8.readthedocs.io/)
 
 Prog8 - Structured Programming Language for 8-bit 6502/65c02 microprocessors
@@ -9,42 +13,75 @@ This is a structured programming language for the 8-bit 6502/6510/65c02 micropro
 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).
 
+**Want to buy me a coffee or a pizza perhaps?**
+
+This project was created over the last couple of years by dedicating thousands of hours of my free time to it, to make it the best I possibly can.
+If you like Prog8, and think it's worth a nice cup of hot coffee or a delicious pizza, 
+you can help me out a little bit over at [ko-fi.com/irmen](https://ko-fi.com/irmen) or [PayPal](https://paypal.me/irmendejong)
+
+
 Documentation
 -------------
 Full documentation (syntax reference, how to use the language and the compiler, etc.) can be found at:
 https://prog8.readthedocs.io/
 
+How to get it/build it
+----------------------
+
+- Download the latest [official release](https://github.com/irmen/prog8/releases) from github.
+- Or, if you want/need a bleeding edge development version, you can:
+  - download a build artifact zipfile from a recent [github action build](https://github.com/irmen/prog8/actions).
+  - you can also compile it yourself from source. [Instructions here](https://prog8.readthedocs.io/en/latest/compiling.html).
+    Note that if you are not using *gradle* to build it, you might have to perform some manual
+    tasks once to make it compile fully. These are explained in the linked instructions. 
+- Alternatively, you can also install the compiler as a package on some linux distros:
+  - Arch (via AUR): [`prog8`](https://aur.archlinux.org/packages/prog8)
+
+Community
+---------
+Most of the development on Prog8 and the use of it is currently centered around 
+the [Commander X16](https://www.commanderx16.com/) retro computer. Their [discord server](https://discord.gg/nS2PqEC) contains a small channel
+dedicated to Prog8. Other than that, use the issue tracker on github.
+
+
 Software license
 ----------------
-GNU GPL 3.0, see file LICENSE
+GNU GPL 3.0 (see file LICENSE), with exception for generated code:
 
-- 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.
+- The compiler and its libraries are free to use according to the terms of the GNU GPL 3.0
+- *exception:* the resulting files (intermediate source codes and resulting binary program) created by the compiler
+  are excluded from the GPL and are free to use in whatever way desired, commercially or not.
 
 
 What does Prog8 provide?
 ------------------------
 
-- 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
+- all advantages of a higher level language over having to write assembly code manually
+- programs run very fast because it's compiled to native machine code
+- code often is smaller and faster than equivalent C code compiled with CC65 or even LLVM-MOS
+- modularity, symbol scoping, subroutines. No need for forward declarations.
 - various data types other than just bytes (16-bit words, floats, strings)
-- floating point math is supported if the target system provides floating point library routines (C64 and Cx16 both do)
+- floating point math is supported on certain targets
+- access to most Kernal ROM routines as external subroutine definitions you can call normally
+- tight control over Zeropage usage
+- programs can be run multiple times without reloading because of automatic variable (re)initializations.
+- programs can be configured to execute in ROM
 - 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
+- conditional branches that map 1:1 to cpu status flags
 - ``when`` statement to provide a concise jump table alternative to if/elseif chains
+- ``on .. goto`` statement for fast jump tables
 - ``in`` expression for concise and efficient multi-value/containment check 
-- many built-in functions such as ``sin``, ``cos``, ``rnd``, ``abs``, ``min``, ``max``, ``sqrt``, ``msb``, ``rol``, ``ror``, ``swap``, ``sort`` and ``reverse``
+- ``defer`` statement to help write concise and robust subroutine cleanup logic
+- several specialized built-in functions such as ``lsb``, ``msb``, ``min``, ``max``, ``rol``, ``ror``
 - 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
+- subroutines can return more than one result value
 - 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.
-- encode strings and characters into petscii or screencodes as desired (C64/Cx16)
+- supports the sixteen 'virtual' 16-bit registers R0 - R15 from the Commander X16 (also available on other targets)
+- encode strings and characters into petscii or screencodes or even other encodings
+- Automatic ROM/RAM bank switching on certain compiler targets when calling routines in other banks
+- 50 Kb of available program RAM size on the C64 by default; because Basic ROM is banked out altogether 
 
 *Rapid edit-compile-run-debug cycle:*
 
@@ -55,9 +92,11 @@ What does Prog8 provide?
 
 *Multiple supported compiler targets* (contributions to improve these or to add support for other machines are welcome!):
 
+- "cx16": [CommanderX16](https://www.commanderx16.com)  (65c02 CPU)
 - "c64": Commodore-64  (6502 like CPU)
 - "c128": Commodore-128  (6502 like CPU - the Z80 cpu mode is not supported)
-- "cx16": [CommanderX16](https://www.commanderx16.com)  (65c02 CPU)
+- "pet32": Commodore PET (limited support)
+- via external configurable targets: Atari 800 XL, Neo6502, NES, C64OS, ...
 - If you only use standard kernal and prog8 library routines, it is possible to compile the *exact same program* for different machines (just change the compiler target flag)
 
 
@@ -75,7 +114,12 @@ IntelliJ IDEA with the Kotlin plugin).
 
 It's handy to have an emulator (or a real machine perhaps!) to run the programs on. The compiler assumes the presence
 of the [Vice emulator](http://vice-emu.sourceforge.net/)  for the C64 target,
-and the [x16emu emulator](https://github.com/commanderx16/x16-emulator) for the CommanderX16 target.
+and a recent emulator version (R42 or newer) for the CommanderX16, such as [x16emu](https://cx16forum.com/forum/viewforum.php?f=30) 
+(preferred, this is the official emulator. If required, source code is [here](https://github.com/X16Community/x16-emulator/)).
+There is also [Box16](https://github.com/indigodarkwolf/box16) which has powerful debugging features.
+
+**Syntax highlighting:** for a few different editors, syntax highlighting definition files are provided.
+Look in the [syntax-files](https://github.com/irmen/prog8/tree/master/syntax-files) directory in the github repository to find them.
 
 
 Example code
@@ -85,14 +129,13 @@ This code calculates prime numbers using the Sieve of Eratosthenes algorithm::
 
     %import textio
     %zeropage basicsafe
-    
+
     main {
-    
-        ubyte[256] sieve
+        bool[256] sieve
         ubyte candidate_prime = 2       ; is increased in the loop
     
         sub start() {
-            sys.memset(sieve, 256, false)   ; clear the sieve
+            sys.memset(sieve, 256, 0)   ; clear the sieve
             txt.print("prime numbers up to 255:\n\n")
             ubyte amount=0
             repeat {
@@ -128,9 +171,6 @@ This code calculates prime numbers using the Sieve of Eratosthenes algorithm::
         }
     }
 
-
-
-
 when compiled an ran on a C-64 you'll get:
 
 ![c64 screen](docs/source/_static/primes_example.png)

beanshell/beanshell.iml

@@ -10,7 +10,15 @@
     <orderEntry type="sourceFolder" forTests="false" />
     <orderEntry type="library" name="KotlinJavaRuntime" level="project" />
     <orderEntry type="library" name="jetbrains.kotlinx.cli.jvm" level="project" />
-    <orderEntry type="library" name="github.hypfvieh.dbus.java" level="project" />
-    <orderEntry type="library" name="slf4j.simple" level="project" />
+    <orderEntry type="library" name="michael.bull.kotlin.result.jvm" level="project" />
+    <orderEntry type="module-library">
+      <library>
+        <CLASSES>
+          <root url="jar://$MODULE_DIR$/lib/bsh-3.0.0-SNAPSHOT.jar!/" />
+        </CLASSES>
+        <JAVADOC />
+        <SOURCES />
+      </library>
+    </orderEntry>
   </component>
 </module>

beanshell/build.gradle.kts

@@ -0,0 +1,65 @@
+import org.jetbrains.kotlin.gradle.dsl.JvmTarget
+
+plugins {
+    id("application")
+    kotlin("jvm")
+}
+
+val serverMainClassName = "prog8lsp.MainKt"
+val applicationName = "prog8-beanshell"
+
+application {
+    mainClass.set(serverMainClassName)
+    description = "Code completions, diagnostics and more for Prog8"
+    // applicationDefaultJvmArgs = listOf("-DkotlinLanguageServer.version=$version")
+    applicationDistribution.into("bin") {
+        filePermissions {
+            user {
+                read=true
+                execute=true
+                write=true
+            }
+            other.execute = true
+            group.execute = true
+        }
+    }
+}
+
+repositories {
+    mavenCentral()
+}
+
+dependencies {
+    implementation(files("lib/bsh-3.0.0-SNAPSHOT.jar"))
+}
+
+configurations.forEach { config ->
+    config.resolutionStrategy {
+        preferProjectModules()
+    }
+}
+
+sourceSets.main {
+    java.srcDir("src")
+    resources.srcDir("resources")
+}
+
+tasks.startScripts {
+    applicationName = "prog8-beanshell"
+}
+
+tasks.register<Exec>("fixFilePermissions") {
+    // When running on macOS or Linux the start script
+    // needs executable permissions to run.
+
+    onlyIf { !System.getProperty("os.name").lowercase().contains("windows") }
+    commandLine("chmod", "+x", "${tasks.installDist.get().destinationDir}/bin/prog8-beanshell")
+}
+
+tasks.installDist {
+    finalizedBy("fixFilePermissions")
+}
+
+tasks.build {
+    finalizedBy("installDist")
+}

beanshell/src/prog8beanshell/CommandLineReader.kt

@@ -0,0 +1,48 @@
+package prog8beanshell
+
+import java.io.FilterReader
+import java.io.Reader
+
+
+class CommandLineReader(val input: Reader): FilterReader(input)  {
+    private val normal = 0
+    private val lastCharNL = 1
+    private val sentSemi = 2
+    private var state = lastCharNL
+
+    override fun read(): Int {
+        if (state == sentSemi) {
+            this.state = lastCharNL
+            return 10
+        } else {
+            var b = input.read()
+            while(b==13) b = input.read()
+
+            if (b == 10) {
+                if (this.state == lastCharNL) {
+                    b = 59
+                    this.state = sentSemi
+                } else {
+                    this.state = lastCharNL
+                }
+            } else {
+                this.state = normal
+            }
+
+            return b
+        }
+
+    }
+
+    override fun read(buff: CharArray, off: Int, len: Int): Int {
+        val b = read()
+        if (b == -1) {
+            return -1
+        } else {
+            buff[off] = b.toChar()
+            return 1
+        }
+
+    }
+}
+

beanshell/src/prog8beanshell/Main.kt

@@ -0,0 +1,23 @@
+package prog8beanshell
+
+import bsh.FileReader
+import bsh.Interpreter
+
+
+class BeanshellInterpreter {
+
+    fun run(symbols: Map<String, Any>) {
+        val interpreter = Interpreter(CommandLineReader(FileReader(System.`in`)), System.out, System.err, true)
+        interpreter.setExitOnEOF(false)
+        symbols.forEach { (name, value) -> interpreter.set(name, value) }
+        interpreter.run()
+    }
+}
+
+fun main(args: Array<String>) {
+    val i = BeanshellInterpreter()
+    i.run(mapOf(
+        "env" to System.getenv(),
+        "args" to args
+    ))
+}

benchmark-program/Makefile

@@ -0,0 +1,10 @@
+.PHONY:  clean run
+
+run:
+	prog8c -target cx16 benchmark.p8
+	x16emu -run -prg benchmark.prg -warp
+
+clean:
+	rm -f *.prg *.PRG *.asm *.vice-* *.BIN *.PAL *.zip *.7z
+
+

benchmark-program/b_3d.p8

@@ -0,0 +1,109 @@
+%import textio
+%import math
+
+rotate3d {
+    const ubyte WIDTH = 40
+    const ubyte HEIGHT = 30
+
+    sub benchmark(uword max_time) -> uword {
+
+        uword anglex
+        uword angley
+        uword anglez
+        uword frames
+
+        txt.nl()
+        cbm.SETTIM(0,0,0)
+
+        while cbm.RDTIM16()<max_time {
+            matrix_math.rotate_vertices(msb(anglex), msb(angley), msb(anglez))
+            draw_edges()   ; doesn't really draw anything in the benchmark, but does do the screen calculations
+            anglex+=500
+            angley+=215
+            anglez+=453
+            frames++
+        }
+
+        return frames
+    }
+
+    sub draw_edges() {
+
+        ; plot the points of the 3d cube
+        ; first the points on the back, then the points on the front (painter algorithm)
+
+        ubyte @zp i
+        word @zp rz
+        word @zp persp
+        byte @shared sx
+        byte @shared sy
+
+        for i in 0 to len(matrix_math.xcoor)-1 {
+            rz = matrix_math.rotatedz[i]
+            if rz >= 10 {
+                persp = 600 + rz/64
+                sx = matrix_math.rotatedx[i] / persp as byte + WIDTH/2
+                sy = matrix_math.rotatedy[i] / persp as byte + HEIGHT/2
+                ;; txt.setcc(sx as ubyte, sy as ubyte, 46, 7)
+            }
+        }
+
+        for i in 0 to len(matrix_math.xcoor)-1 {
+            rz = matrix_math.rotatedz[i]
+            if rz < 10 {
+                persp = 600 + rz/64
+                sx = matrix_math.rotatedx[i] / persp as byte + WIDTH/2
+                sy = matrix_math.rotatedy[i] / persp as byte + HEIGHT/2
+                ;; txt.setcc(sx as ubyte, sy as ubyte, 81, 7)
+            }
+        }
+
+        txt.chrout('.')
+    }
+}
+
+matrix_math {
+    ; vertices
+    word[] xcoor = [ -40, -40, -40, -40,  40,  40,  40, 40 ]
+    word[] ycoor = [ -40, -40,  40,  40, -40, -40,  40, 40 ]
+    word[] zcoor = [ -40,  40, -40,  40, -40,  40, -40, 40 ]
+
+    ; storage for rotated coordinates
+    word[len(xcoor)] rotatedx
+    word[len(ycoor)] rotatedy
+    word[len(zcoor)] rotatedz
+
+    sub rotate_vertices(ubyte ax, ubyte ay, ubyte az) {
+        ; rotate around origin (0,0,0)
+
+        ; set up the 3d rotation matrix values
+        word wcosa = math.cos8(ax)
+        word wsina = math.sin8(ax)
+        word wcosb = math.cos8(ay)
+        word wsinb = math.sin8(ay)
+        word wcosc = math.cos8(az)
+        word wsinc = math.sin8(az)
+
+        word wcosa_sinb = wcosa*wsinb / 128
+        word wsina_sinb = wsina*wsinb / 128
+
+        word Axx = wcosa*wcosb / 128
+        word Axy = (wcosa_sinb*wsinc - wsina*wcosc) / 128
+        word Axz = (wcosa_sinb*wcosc + wsina*wsinc) / 128
+        word Ayx = wsina*wcosb / 128
+        word Ayy = (wsina_sinb*wsinc + wcosa*wcosc) / 128
+        word Ayz = (wsina_sinb*wcosc - wcosa*wsinc) / 128
+        word Azx = -wsinb
+        word Azy = wcosb*wsinc / 128
+        word Azz = wcosb*wcosc / 128
+
+        ubyte @zp i
+        for i in 0 to len(xcoor)-1 {
+            ; don't normalize by dividing by 128, instead keep some precision for perspective calc later
+            rotatedx[i] = Axx*xcoor[i] + Axy*ycoor[i] + Axz*zcoor[i]
+            rotatedy[i] = Ayx*xcoor[i] + Ayy*ycoor[i] + Ayz*zcoor[i]
+            rotatedz[i] = Azx*xcoor[i] + Azy*ycoor[i] + Azz*zcoor[i]
+        }
+    }
+
+}

benchmark-program/b_adpcm.p8

@@ -0,0 +1,89 @@
+adpcm {
+
+    sub decode_benchmark(uword max_time) -> uword {
+        uword num_blocks
+        txt.nl()
+        cbm.SETTIM(0,0,0)
+
+        while cbm.RDTIM16()<max_time {
+            adpcm.init(0,0)
+            uword @requirezp nibbles_ptr = $a000 ; for benchmark purposes, the exact nibbles don't really matter, so we just take the basic ROM as input
+            repeat 252/2 {
+                unroll 2 {
+                    ubyte @zp nibble = @(nibbles_ptr)
+                    adpcm.decode_nibble(nibble & 15)     ; first word  (note: upper nibble needs to be zero!)
+                    adpcm.decode_nibble(nibble>>4)       ; second word  (note: upper nibble is zero, after the shifts.)
+                    nibbles_ptr++
+                }
+            }
+            num_blocks++
+            txt.chrout('.')
+        }
+
+        return num_blocks
+    }
+
+    ; IMA ADPCM decoder.  Supports mono and stereo streams.
+
+    byte[] t_index = [ -1, -1, -1, -1, 2, 4, 6, 8, -1, -1, -1, -1, 2, 4, 6, 8]
+    uword[] t_step = [
+            7, 8, 9, 10, 11, 12, 13, 14,
+            16, 17, 19, 21, 23, 25, 28, 31,
+            34, 37, 41, 45, 50, 55, 60, 66,
+            73, 80, 88, 97, 107, 118, 130, 143,
+            157, 173, 190, 209, 230, 253, 279, 307,
+            337, 371, 408, 449, 494, 544, 598, 658,
+            724, 796, 876, 963, 1060, 1166, 1282, 1411,
+            1552, 1707, 1878, 2066, 2272, 2499, 2749, 3024,
+            3327, 3660, 4026, 4428, 4871, 5358, 5894, 6484,
+            7132, 7845, 8630, 9493, 10442, 11487, 12635, 13899,
+            15289, 16818, 18500, 20350, 22385, 24623, 27086, 29794,
+            32767]
+
+    uword @requirezp predict       ; decoded 16 bit pcm sample for first channel.
+    ubyte @requirezp index
+    uword @requirezp pstep
+
+    sub init(uword startPredict, ubyte startIndex) {
+        ; initialize first decoding channel.
+        predict = startPredict
+        index = startIndex
+        pstep = t_step[index]
+    }
+
+    sub decode_nibble(ubyte @zp nibble) {
+        ; Decoder for a single nibble for the first channel. (value of 'nibble' needs to be strictly 0-15 !)
+        ; This is the hotspot of the decoder algorithm!
+        ; Note that the generated assembly from this is pretty efficient,
+        ; rewriting it by hand in asm seems to improve it only ~10%.
+        cx16.r0s = 0                ; difference
+        if nibble & %0100 !=0
+            cx16.r0s += pstep
+        pstep >>= 1
+        if nibble & %0010 !=0
+            cx16.r0s += pstep
+        pstep >>= 1
+        if nibble & %0001 !=0
+            cx16.r0s += pstep
+        pstep >>= 1
+        cx16.r0s += pstep
+        if nibble & %1000 !=0
+            predict -= cx16.r0
+        else
+            predict += cx16.r0
+
+        ; NOTE: the original C/Python code uses a 32 bits prediction value and clips it to a 16 bit word
+        ;       but for speed reasons we only work with 16 bit words here all the time (with possible clipping error)
+        ; if predicted > 32767:
+        ;    predicted = 32767
+        ; elif predicted < -32767:
+        ;    predicted = - 32767
+
+        index += t_index[nibble] as ubyte
+        if_neg
+            index = 0
+        else if index >= len(t_step)-1
+            index = len(t_step)-1
+        pstep = t_step[index]
+    }
+}

benchmark-program/b_circles.p8

@@ -0,0 +1,111 @@
+%import gfx_lores
+%import math
+
+circles {
+    const ubyte MAX_NUM_CIRCLES = 80
+    const ubyte GROWTH_RATE = 4
+    uword[MAX_NUM_CIRCLES] circle_x
+    uword[MAX_NUM_CIRCLES] circle_y
+    ubyte[MAX_NUM_CIRCLES] circle_radius
+    ubyte color
+    uword total_num_circles
+
+    sub draw(bool use_kernal, uword max_time) -> uword {
+        if use_kernal
+            cx16.set_screen_mode(128)
+        else
+            gfx_lores.graphics_mode()
+
+        math.rndseed(12345,6789)
+        cbm.SETTIM(0,0,0)
+
+        total_num_circles = 0
+        color = 16
+
+        while cbm.RDTIM16()<max_time {
+            if use_kernal {
+                cx16.GRAPH_set_colors(0,0,0)
+                cx16.GRAPH_clear()
+            }
+            else
+                gfx_lores.clear_screen(0)
+            total_num_circles += draw_circles(use_kernal, max_time)
+        }
+
+        if use_kernal
+            cx16.set_screen_mode(3)
+        else {
+            gfx_lores.text_mode()
+        }
+
+        return total_num_circles
+    }
+
+    sub draw_circles(bool use_kernal, uword max_time) -> uword {
+        uword @zp x
+        uword @zp y
+        ubyte @zp radius
+
+        ubyte num_circles
+
+        while num_circles<MAX_NUM_CIRCLES and cbm.RDTIM16()<max_time {
+            x = math.rndw() % 320
+            y = math.rndw() % 240
+            radius = GROWTH_RATE
+            if not_colliding() {
+                while not_edge() and not_colliding() {
+                    radius += GROWTH_RATE
+                }
+                radius -= GROWTH_RATE
+                if radius>0 {
+                    color++
+                    if color==0
+                        color=16
+                    if use_kernal {
+                        cx16.GRAPH_set_colors(color, 255-color, 0)
+                        cx16.GRAPH_draw_oval(x-radius, y-radius, radius*2, radius*2, true)
+                    }
+                    else
+                        gfx_lores.disc(x, y as ubyte, radius, color)
+                    circle_x[num_circles] = x
+                    circle_y[num_circles] = y
+                    circle_radius[num_circles] = radius
+                    num_circles++
+                }
+            }
+        }
+
+        return num_circles
+
+        sub not_colliding() -> bool {
+            if num_circles==0
+                return true
+            ubyte @zp c
+            for c in 0 to num_circles-1 {
+                if distance(c) < (radius as uword) + circle_radius[c]
+                    return false
+            }
+            return true
+        }
+
+        sub distance(ubyte cix) -> uword {
+            word dx = x as word - circle_x[cix]
+            word dy = y as word - circle_y[cix]
+            uword sqx = dx*dx as uword
+            uword sqy = dy*dy as uword
+            return sqrt(sqx + sqy)
+        }
+
+        sub not_edge() -> bool {
+            if x as word - radius < 0
+                return false
+            if x + radius >= 320
+                return false
+            if y as word - radius < 0
+                return false
+            if y + radius >= 240
+                return false
+            return true
+        }
+    }
+}

benchmark-program/b_life.p8

@@ -0,0 +1,123 @@
+; conway's game of life.
+
+%import math
+%import textio
+
+life {
+    const ubyte WIDTH = 40
+    const ubyte HEIGHT = 30
+    const uword STRIDE = $0002+WIDTH
+    uword world1 = memory("world1", (WIDTH+2)*(HEIGHT+2), 0)
+    uword world2 = memory("world2", (WIDTH+2)*(HEIGHT+2), 0)
+    uword @requirezp active_world = world1
+
+   sub benchmark(uword max_time) -> uword {
+        txt.clear_screen()
+        sys.memset(world1, (WIDTH+2)*(HEIGHT+2), 0)
+        sys.memset(world2, (WIDTH+2)*(HEIGHT+2), 0)
+
+        set_start_gen()
+
+        uword gen
+        cbm.SETTIM(0,0,0)
+
+        while cbm.RDTIM16()<max_time {
+            next_gen()
+            gen++
+        }
+
+        return gen
+    }
+
+    sub set_start_gen() {
+
+; some way to set a custom start generation:
+;        str start_gen = "                " +
+;                        "                " +
+;                        "                " +
+;                        "          **    " +
+;                        "        *    *  " +
+;                        "       *        " +
+;                        "       *     *  " +
+;                        "       ******   " +
+;                        "                " +
+;                        "                " +
+;                        "                " +
+;                        "                " +
+;                        "                " +
+;                        "                " +
+;                        "                " +
+;                        "               "
+;
+;        for y in 0 to 15 {
+;            for x in 0 to 15 {
+;                if start_gen[y*16 + x]=='*'
+;                    active_world[offset + x] = 1
+;            }
+;            offset += STRIDE
+;        }
+
+        ; randomize whole world
+        math.rndseed(12345,9999)
+        uword offset = STRIDE+1
+        ubyte x
+        ubyte y
+        for y in 0 to HEIGHT-1 {
+            for x in 0 to WIDTH-1 {
+                active_world[offset+x] = math.rnd() & 1
+            }
+            offset += STRIDE
+        }
+    }
+
+    sub next_gen() {
+        const ubyte DXOFFSET = 0
+        const ubyte DYOFFSET = 0
+        ubyte[2] cell_chars = [sc:' ', sc:'●']
+
+        uword @requirezp new_world = world1
+        if active_world == world1
+            new_world = world2
+
+        ; To avoid re-calculating word index lookups into the new- and active world arrays,
+        ; we calculate the required pointer values upfront.
+        ; Inside the loop we can use ptr+x just fine (results in efficient LDA (ptr),Y instruction because x is a byte type),
+        ; and for each row we simply add the stride to the pointer.
+        ; It's more readable to use active_world[offset] etc, but offset is a word value, and this produces
+        ; inefficient assembly code because we can't use a register indexed mode in this case. Costly inside a loop.
+
+        uword @requirezp new_world_ptr = new_world + STRIDE+1-DXOFFSET
+        uword @requirezp active_world_ptr = active_world + STRIDE+1-DXOFFSET
+
+        ubyte x
+        ubyte y
+        for y in DYOFFSET to HEIGHT+DYOFFSET-1 {
+
+            cx16.vaddr_autoincr(1, $b000 + 256*y, 0, 2)     ;  allows us to use simple Vera data byte assigns later instead of setchr() calls
+
+            for x in DXOFFSET to WIDTH+DXOFFSET-1 {
+                ; count the living neighbors
+                ubyte cell = @(active_world_ptr + x)
+                uword @requirezp ptr = active_world_ptr + x - STRIDE - 1
+                ubyte neighbors = @(ptr) + @(ptr+1) + @(ptr+2) +
+                                  @(ptr+STRIDE) + cell + @(ptr+STRIDE+2) +
+                                  @(ptr+STRIDE*2) + @(ptr+STRIDE*2+1) + @(ptr+STRIDE*2+2)
+
+                ; apply game of life rules
+                if neighbors==3
+                    cell=1
+                else if neighbors!=4
+                    cell=0
+                @(new_world_ptr + x) = cell
+
+                ; draw new cell
+                ; txt.setchr(x,y,cell_chars[cell])
+                cx16.VERA_DATA0 = cell_chars[cell]
+            }
+            active_world_ptr += STRIDE
+            new_world_ptr += STRIDE
+        }
+
+        active_world = new_world
+    }
+}

benchmark-program/b_mandelbrot.p8

@@ -0,0 +1,54 @@
+%import textio
+%import floats
+
+mandelbrot {
+    const ubyte width = 39
+    const ubyte height = 29
+    const ubyte max_iter = 15
+
+    sub calc(uword max_time) -> uword  {
+        uword num_pixels
+        ubyte pixelx
+        ubyte pixely
+
+        txt.home()
+        cbm.SETTIM(0,0,0)
+
+        while cbm.RDTIM16() < max_time {
+            for pixely in 0 to height-1 {
+                float yy = (pixely as float)/0.40/height - 1.3
+
+                for pixelx in 0 to width-1 {
+                    float xx = (pixelx as float)/0.32/width - 2.2
+
+                    float xsquared = 0.0
+                    float ysquared = 0.0
+                    float x = 0.0
+                    float y = 0.0
+                    ubyte iter = 0
+
+                    while iter<max_iter and xsquared+ysquared<4.0 {
+                        y = x*y*2.0 + yy
+                        x = xsquared - ysquared + xx
+                        xsquared = x*x
+                        ysquared = y*y
+                        iter++
+                    }
+                    txt.color2(1, max_iter-iter)
+                    txt.spc()
+                    num_pixels++
+
+                    if cbm.RDTIM16()>=max_time
+                        goto finished
+                }
+                txt.nl()
+            }
+
+            txt.clear_screen()
+        }
+
+finished:
+        txt.color2(1, 6)
+        return num_pixels
+    }
+}

benchmark-program/b_maze.p8

@@ -0,0 +1,343 @@
+%import textio
+%import math
+
+; Even though prog8 only has support for extremely limited recursion,
+; you can write recursive algorithms with a bit of extra work by building your own explicit stack structure.
+; This program shows a depth-first maze generation algorithm (1 possible path from start to finish),
+; and a depth-first maze solver algorithm, both using a stack to store the path taken.
+
+; Note: this program can be compiled for multiple target systems.
+
+maze {
+    uword score
+
+    sub bench(uword max_time) -> uword {
+        txt.nl()
+        score=0
+        math.rndseed(2345,44332)
+        cbm.SETTIM(0,0,0)
+        while cbm.RDTIM16()<max_time {
+            maze.initialize()
+            maze.drawStartFinish()
+            if maze.generate(max_time) {
+                maze.openpassages()
+                maze.drawStartFinish()
+                if maze.solve(max_time) {
+                    maze.drawStartFinish()
+                } else break
+            } else break
+        }
+
+        return score
+    }
+
+    const uword screenwidth = 40
+    const uword screenheight = 30
+
+    const ubyte numCellsHoriz = (screenwidth-1) / 2
+    const ubyte numCellsVert = (screenheight-1) / 2
+
+    ; maze start and finish cells
+    const ubyte startCx = 0
+    const ubyte startCy = 0
+    const ubyte finishCx = numCellsHoriz-1
+    const ubyte finishCy = numCellsVert-1
+
+    ; cell properties
+    const ubyte STONE = 128
+    const ubyte WALKED = 64
+    const ubyte BACKTRACKED = 32
+    const ubyte UP = 1
+    const ubyte RIGHT = 2
+    const ubyte DOWN = 4
+    const ubyte LEFT = 8
+    const ubyte WALLCOLOR = 12
+    const ubyte EMPTYCOLOR = 0
+
+    ; unfortunately on larger screens (cx16), the number of cells exceeds 256 and doesn't fit in a regular array anymore.
+    uword cells = memory("cells", numCellsHoriz*numCellsVert, 0)
+
+    ubyte[256] cx_stack
+    ubyte[256] cy_stack
+    ubyte stackptr
+
+    ubyte[4] directionflags = [LEFT,RIGHT,UP,DOWN]
+
+    sub generate(uword max_time) -> bool {
+        ubyte cx = startCx
+        ubyte cy = startCy
+
+        stackptr = 0
+        @(celladdr(cx,cy)) &= ~STONE
+        drawCell(cx, cy)
+        uword cells_to_carve = numCellsHoriz * numCellsVert - 1
+
+        while cbm.RDTIM16()<max_time {
+carve_restart_after_repath:
+            ubyte direction = choose_uncarved_direction()
+            if direction==0 {
+                ;backtrack
+                stackptr--
+                if stackptr==255 {
+                    ; stack empty.
+                    ; repath if we are not done yet. (this is a workaround for the prog8 256 array lenght limit)
+                    if cells_to_carve!=0 {
+                        if repath()
+                            goto carve_restart_after_repath
+                    }
+                    return true
+                }
+                cx = cx_stack[stackptr]
+                cy = cy_stack[stackptr]
+            } else {
+                cx_stack[stackptr] = cx
+                cy_stack[stackptr] = cy
+                stackptr++
+                if stackptr==0 {
+                    ; stack overflow, we can't track our path any longer.
+                    ; repath if we are not done yet. (this is a workaround for the prog8 256 array lenght limit)
+                    if cells_to_carve!=0 {
+                        if repath()
+                            goto carve_restart_after_repath
+                    }
+                    return true
+                }
+                @(celladdr(cx,cy)) |= direction
+                when direction {
+                    UP -> {
+                        cy--
+                        @(celladdr(cx,cy)) |= DOWN
+                    }
+                    RIGHT -> {
+                        cx++
+                        @(celladdr(cx,cy)) |= LEFT
+
+                        score++
+                    }
+                    DOWN -> {
+                        cy++
+                        @(celladdr(cx,cy)) |= UP
+                    }
+                    LEFT -> {
+                        cx--
+                        @(celladdr(cx,cy)) |= RIGHT
+                    }
+                }
+                @(celladdr(cx,cy)) &= ~STONE
+                cells_to_carve--
+                drawCell(cx, cy)
+            }
+        }
+        return false
+
+        sub repath() -> bool {
+            ; repath: try to find a new start cell with possible directions.
+            ; we limit our number of searches so that the algorith doesn't get stuck
+            ; for too long on bad rng... just accept a few unused cells in that case.
+            repeat 255 {
+                do {
+                    cx = math.rnd() % numCellsHoriz
+                    cy = math.rnd() % numCellsVert
+                } until @(celladdr(cx, cy)) & STONE ==0
+                if available_uncarved()!=0
+                    return true
+            }
+            return false
+        }
+
+        sub available_uncarved() -> ubyte {
+            ubyte candidates = 0
+            if cx>0 and @(celladdr(cx-1, cy)) & STONE !=0
+                candidates |= LEFT
+            if cx<numCellsHoriz-1 and @(celladdr(cx+1, cy)) & STONE !=0
+                candidates |= RIGHT
+            if cy>0 and @(celladdr(cx, cy-1)) & STONE !=0
+                candidates |= UP
+            if cy<numCellsVert-1 and @(celladdr(cx, cy+1)) & STONE !=0
+                candidates |= DOWN
+            return candidates
+        }
+
+        sub choose_uncarved_direction() -> ubyte {
+            ubyte candidates =  available_uncarved()
+            if candidates==0
+                return 0
+
+            repeat {
+                ubyte choice = candidates & directionflags[math.rnd() & 3]
+                if choice!=0
+                    return choice
+            }
+        }
+    }
+
+    sub openpassages() {
+        ; open just a few extra passages, so that multiple routes are possible in theory.
+        ubyte numpassages
+        ubyte cx
+        ubyte cy
+        do {
+            do {
+                cx = math.rnd() % (numCellsHoriz-2) + 1
+                cy = math.rnd() % (numCellsVert-2) + 1
+            } until @(celladdr(cx, cy)) & STONE ==0
+            ubyte direction = directionflags[math.rnd() & 3]
+            if @(celladdr(cx, cy)) & direction == 0 {
+                when direction {
+                    LEFT -> {
+                        if @(celladdr(cx-1,cy)) & STONE == 0 {
+                            @(celladdr(cx,cy)) |= LEFT
+                            drawCell(cx,cy)
+                            numpassages++
+                        }
+                    }
+                    RIGHT -> {
+                        if @(celladdr(cx+1,cy)) & STONE == 0 {
+                            @(celladdr(cx,cy)) |= RIGHT
+                            drawCell(cx,cy)
+                            numpassages++
+                        }
+                    }
+                    UP -> {
+                        if @(celladdr(cx,cy-1)) & STONE == 0 {
+                            @(celladdr(cx,cy)) |= UP
+                            drawCell(cx,cy)
+                            numpassages++
+                        }
+                    }
+                    DOWN -> {
+                        if @(celladdr(cx,cy+1)) & STONE == 0 {
+                            @(celladdr(cx,cy)) |= DOWN
+                            drawCell(cx,cy)
+                            numpassages++
+                        }
+                    }
+                }
+            }
+        } until numpassages==10
+    }
+
+    sub solve(uword max_time) -> bool {
+        ubyte cx = startCx
+        ubyte cy = startCy
+        const uword max_path_length = 1024
+
+        ; the path through the maze can be longer than 256 so doesn't fit in a regular array.... :(
+        uword pathstack = memory("pathstack", max_path_length, 0)
+        uword pathstackptr = 0
+
+        @(celladdr(cx,cy)) |= WALKED
+        ; txt.setcc(cx*2+1, cy*2+1, 81, 1)
+
+        while cbm.RDTIM16()<max_time {
+solve_loop:
+            if cx==finishCx and cy==finishCy {
+                ;txt.home()
+                txt.print("found! path length: ")
+                txt.print_uw(pathstackptr)
+                txt.nl()
+                return true
+            }
+
+            ubyte cell = @(celladdr(cx,cy))
+            if cell & UP!=0 and @(celladdr(cx,cy-1)) & (WALKED|BACKTRACKED) ==0 {
+                @(pathstack + pathstackptr) = UP
+                ;txt.setcc(cx*2+1, cy*2, 81, 3)
+                cy--
+            }
+            else if cell & DOWN !=0 and @(celladdr(cx,cy+1)) & (WALKED|BACKTRACKED) ==0 {
+                @(pathstack + pathstackptr) = DOWN
+                ;txt.setcc(cx*2+1, cy*2+2, 81, 3)
+                cy++
+            }
+            else if cell & LEFT !=0 and @(celladdr(cx-1,cy)) & (WALKED|BACKTRACKED) ==0 {
+                @(pathstack + pathstackptr) = LEFT
+                ;txt.setcc(cx*2, cy*2+1, 81, 3)
+                cx--
+            }
+            else if cell & RIGHT !=0 and @(celladdr(cx+1,cy)) & (WALKED|BACKTRACKED) ==0 {
+                @(pathstack + pathstackptr) = RIGHT
+                ;txt.setcc(cx*2+2, cy*2+1, 81, 3)
+                cx++
+            }
+            else {
+                ; dead end, pop stack
+                pathstackptr--
+                if pathstackptr==65535 {
+                    txt.print("no solution?!\n")
+                    return true
+                }
+                @(celladdr(cx,cy)) |= BACKTRACKED
+                ;txt.setcc(cx*2+1, cy*2+1, 81, 2)
+                when @(pathstack + pathstackptr) {
+                    UP -> {
+                        ;txt.setcc(cx*2+1, cy*2+2, 81, 9)
+                        cy++
+                    }
+                    DOWN -> {
+                        ;txt.setcc(cx*2+1, cy*2, 81, 9)
+                        cy--
+                    }
+                    LEFT -> {
+                        ;txt.setcc(cx*2+2, cy*2+1, 81, 9)
+                        cx++
+                    }
+                    RIGHT -> {
+                        ;txt.setcc(cx*2, cy*2+1, 81, 9)
+                        cx--
+
+                        score++
+                    }
+                }
+                goto solve_loop
+            }
+            pathstackptr++
+            if pathstackptr==max_path_length {
+                txt.print("stack overflow, path too long\n")
+                return true
+            }
+            @(celladdr(cx,cy)) |= WALKED
+            ;txt.setcc(cx*2+1, cy*2+1, 81, 1)
+        }
+        return false
+    }
+
+    sub celladdr(ubyte cx, ubyte cy) -> uword {
+        return cells+(numCellsHoriz as uword)*cy+cx
+    }
+
+    sub drawCell(ubyte cx, ubyte cy) {
+        return
+;        ubyte x = cx * 2 + 1
+;        ubyte y = cy * 2 + 1
+;        ubyte doors = @(celladdr(cx,cy))
+;        if doors & UP !=0
+;            txt.setcc(x, y-1, ' ', EMPTYCOLOR)
+;        if doors & RIGHT !=0
+;            txt.setcc(x+1, y, ' ', EMPTYCOLOR)
+;        if doors & DOWN !=0
+;            txt.setcc(x, y+1, ' ', EMPTYCOLOR)
+;        if doors & LEFT !=0
+;            txt.setcc(x-1, y, ' ', EMPTYCOLOR)
+;        if doors & STONE !=0
+;            txt.setcc(x, y, 160, WALLCOLOR)
+;        else
+;            txt.setcc(x, y, 32, EMPTYCOLOR)
+;
+;        if doors & WALKED !=0
+;            txt.setcc(x, y, 81, 1)
+;        if doors & BACKTRACKED !=0
+;            txt.setcc(x, y, 81, 2)
+    }
+
+    sub initialize() {
+        sys.memset(cells, numCellsHoriz*numCellsVert, STONE)
+        ; txt.fill_screen(160, WALLCOLOR)
+        drawStartFinish()
+    }
+
+    sub drawStartFinish() {
+        ; txt.setcc(startCx*2+1,startCy*2+1,sc:'s',5)
+        ; txt.setcc(finishCx*2+1, finishCy*2+1, sc:'f', 13)
+    }
+}

benchmark-program/b_queens.p8

@@ -0,0 +1,63 @@
+%import textio
+
+; Recursive N-Queens solver.
+; The problem is: find all possible ways to place 8 Queen chess pieces on a chess board, so that none of them attacks any other.
+; (this program prints all solutions without taking mirroring and flipping the chess board into account)
+; Note: this program can be compiled for multiple target systems.
+
+queens {
+    const ubyte NUMQUEENS=8
+    ubyte[NUMQUEENS] board
+
+    sub could_place(ubyte row, ubyte col) -> bool {
+        if row==0
+            return true
+        ubyte i
+        for i in 0 to row-1 {
+            if board[i]==col or board[i]-i==col-row or board[i]+i==col+row
+                return false
+        }
+        return true
+    }
+
+    uword solution_count
+    uword maximum_duration
+
+    sub place_queen(ubyte row) -> bool {
+        if row == NUMQUEENS {
+            solution_count++
+            txt.chrout('.')
+            return cbm.RDTIM16()<maximum_duration
+        }
+        bool continue_running=true
+        ubyte col
+        for col in 0 to NUMQUEENS-1 {
+            if could_place(row, col) {
+                board[row] = col
+                ; we need to save the local variables row and col.
+                sys.push(row)
+                sys.push(col)
+                continue_running = place_queen(row + 1)
+                ; restore the local variables after the recursive call.
+                col = sys.pop()
+                row = sys.pop()
+                board[row] = 0
+
+                if not continue_running
+                    break
+            }
+        }
+        return continue_running
+    }
+
+    sub bench(uword max_time) -> uword {
+        solution_count = 0
+        maximum_duration = max_time
+        txt.nl()
+        cbm.SETTIM(0,0,0)
+        while cbm.RDTIM16() < maximum_duration {
+            void place_queen(0)
+        }
+        return solution_count
+    }
+}

benchmark-program/b_sprites.p8

@@ -0,0 +1,69 @@
+%import sprites
+%import coroutines
+%import math
+
+
+animsprites {
+    uword num_iterations
+    ubyte[64] sx
+    ubyte[64] sy
+    ubyte[64] sc
+    ubyte[64] dx
+    ubyte[64] dy
+    uword maximum_duration
+
+    sub benchmark(uword max_duration) -> uword {
+        maximum_duration = max_duration
+        math.rndseed(1122,9876)
+        cx16.set_screen_mode(3)
+        cx16.mouse_config2(1)
+        sprites.set_mousepointer_hand()
+        repeat 64
+            void coroutines.add(animsprite, 0)
+        cx16.mouse_config2(0)
+
+        cbm.SETTIM(0,0,0)
+        coroutines.run(supervisor)
+
+        sprites.reset(0, 64)
+        return num_iterations
+    }
+
+    sub supervisor() -> bool {
+        if cbm.RDTIM16() >= maximum_duration {
+            coroutines.killall()
+            return false
+        }
+        return true
+    }
+
+    sub animsprite() {
+        num_iterations++
+        ; set up the sprite
+        ubyte sprnum = coroutines.current()
+        cx16.r6L, cx16.r7 = sprites.get_data_ptr(0)
+        sprites.init(sprnum, cx16.r6L, cx16.r7, sprites.SIZE_16, sprites.SIZE_16, sprites.COLORS_256, 0)
+        sx[sprnum] = math.rnd()
+        sy[sprnum] = math.rnd()
+        sc[sprnum] = math.rnd()
+        dx[sprnum] = if math.rnd()&1 == 1  1 else 255
+        dy[sprnum] = if math.rnd()&1 == 1  1 else 255
+
+        ; move the sprite around
+        while sc[sprnum]!=0 {
+            animate(sprnum)
+            void coroutines.yield()
+            sprnum = coroutines.current()
+        }
+
+        sub animate(ubyte spr) {
+            defer sc[spr]--
+            sprites.pos(spr, sx[spr], sy[spr])
+            sx[spr] += dx[spr]
+            sy[spr] += dy[spr]
+        }
+
+        ; end the task but replace it with a fresh animated sprite task
+        void coroutines.add(animsprite, 0)
+    }
+}

benchmark-program/b_textelite.p8

@@ -0,0 +1,989 @@
+%import textio
+%import conv
+%import strings
+
+
+textelite {
+
+    const ubyte numforLave = 7      ;  Lave is 7th generated planet in galaxy one
+    const ubyte numforZaonce = 129
+    const ubyte numforDiso = 147
+    const ubyte numforRiedquat = 46
+    uword num_commands
+
+    sub bench(uword max_time) -> uword {
+        num_commands = 0
+        txt.lowercase()
+        cbm.SETTIM(0,0,0)
+        while cbm.RDTIM16()<max_time {
+            reinit()
+            run_commands(max_time)
+        }
+        return num_commands
+    }
+
+    sub reinit() {
+        ;txt.clear_screen()
+        ;txt.print("\n --- TextElite v1.3 ---\n")
+        txt.print("\nnew game\n")
+        elite_planet.set_seed(0, 0)
+        elite_galaxy.travel_to(1, numforLave)
+        elite_market.init(0)  ;  Lave's market is seeded with 0
+        elite_ship.init()
+        elite_planet.display(false, 0)
+        input_index = 0
+    }
+
+    sub run_commands(uword max_time) {
+        while cbm.RDTIM16() < max_time {
+            str input = "????????"
+            ;txt.print("\nCash: ")
+            ;elite_util.print_10s(elite_ship.cash)
+            ;txt.print("\nCommand (?=help): ")
+            ubyte num_chars = next_input(input)
+            ;txt.nl()
+            if num_chars!=0 {
+                when input[0] {
+                    'q' -> {
+                        bool has_error = false
+                        if elite_galaxy.number != 2 {
+                            txt.print("\nERROR: galaxy is not 2: ")
+                            txt.print_ub(elite_galaxy.number)
+                            txt.nl()
+                            has_error=true
+                        }
+                        if elite_planet.number != 164 {
+                            txt.print("\nERROR: planet is not 164: ")
+                            txt.print_ub(elite_planet.number)
+                            txt.nl()
+                            has_error=true
+                        }
+                        if elite_planet.x != 116 {
+                            txt.print("\nERROR: planet.x is not 116: ")
+                            txt.print_ub(elite_planet.x)
+                            txt.nl()
+                            has_error=true
+                        }
+                        if elite_planet.y != 201 {
+                            txt.print("\nERROR: planet.y is not 201: ")
+                            txt.print_ub(elite_planet.y)
+                            txt.nl()
+                            has_error=true
+                        }
+                        if "ribeen" != elite_planet.name {
+                            txt.print("\nERROR: planet.name is not 'ribeen': ")
+                            txt.print(elite_planet.name)
+                            txt.nl()
+                            has_error=true
+                        }
+                        if elite_ship.cash != 1212 {
+                            txt.print("\nERROR: cash is not 1212: ")
+                            txt.print_uw(elite_ship.cash)
+                            txt.nl()
+                            has_error=true
+                        }
+                        if elite_ship.fuel != 50 {
+                            txt.print("\nERROR: fuel is not 50:")
+                            txt.print_ub(elite_ship.fuel)
+                            txt.nl()
+                            has_error=true
+                        }
+                        if elite_ship.cargohold[0] != 3 {
+                            txt.print("\nERROR: food is not 3:")
+                            txt.print_ub(elite_ship.cargohold[0])
+                            txt.nl()
+                            has_error=true
+                        }
+                        if elite_ship.cargohold[1] != 0 {
+                            txt.print("\nERROR: textiles is not 0:")
+                            txt.print_ub(elite_ship.cargohold[1])
+                            txt.nl()
+                            has_error=true
+                        }
+                        if has_error
+                            sys.exit(1)
+                        return
+                    }
+                    'b' -> elite_trader.do_buy()
+                    's' -> elite_trader.do_sell()
+                    'f' -> elite_trader.do_fuel()
+                    'j' -> elite_trader.do_jump()
+                    't' -> elite_trader.do_teleport()
+                    'g' -> elite_trader.do_next_galaxy()
+                    'i' -> elite_trader.do_info()
+                    'm' -> {
+                        if input[1]=='a' and input[2]=='p'
+                            elite_trader.do_map()
+                        else
+                            elite_trader.do_show_market()
+                    }
+                    'l' -> elite_trader.do_local()
+                    'c' -> elite_trader.do_cash()
+                    'h' -> elite_trader.do_hold()
+                }
+                num_commands++
+            }
+        }
+    }
+
+    str[] inputs = [
+        "i",
+        "diso",
+        "i",
+        "lave",
+        "m",
+        "b",
+        "food",
+        "15",
+        "map",
+        "g",
+        "map",
+        "l",
+        "j",
+        "zao",
+        "s",
+        "food",
+        "12",
+        "tele",
+        "quti",
+        "tele",
+        "aro",
+        "i",
+        "diso",
+        "i",
+        "lave",
+        "i",
+        "zao",
+        "galhyp",
+        "fuel",
+        "20",
+        "j",
+        "rib",
+        "i",
+        "rib",
+        "i",
+        "tiri",
+        "q",
+        0
+    ]
+
+    ubyte input_index
+
+    sub next_input(str buffer) -> ubyte {
+        input_index++
+        return strings.copy(inputs[input_index], buffer)
+    }
+}
+
+elite_trader {
+    str input = "??????????"
+    ubyte num_chars
+
+    sub do_jump() {
+        ;txt.print("\nJump to what system? ")
+        jump_to_system()
+    }
+
+    sub do_teleport() {
+        ;txt.print("\nCheat! Teleport to what system? ")
+        ubyte fuel = elite_ship.fuel
+        elite_ship.fuel = 255
+        jump_to_system()
+        elite_ship.fuel = fuel
+    }
+
+    sub jump_to_system() {
+        void textelite.next_input(input)
+        ubyte current_planet = elite_planet.number
+        ubyte x = elite_planet.x
+        ubyte y = elite_planet.y
+        if elite_galaxy.search_closest_planet(input) {
+            ubyte distance = elite_planet.distance(x, y)
+            if distance <= elite_ship.fuel {
+                elite_galaxy.init_market_for_planet()
+                elite_ship.fuel -= distance
+                ;txt.print("\n\nHyperspace jump! Arrived at:\n")
+                elite_planet.display(true,0 )
+                return
+            }
+            ;txt.print("\nInsufficient fuel\n")
+        } else {
+            ;txt.print(" Not found!\n")
+        }
+        elite_galaxy.travel_to(elite_galaxy.number, current_planet)
+    }
+
+    sub do_buy() {
+        ;txt.print("\nBuy what commodity? ")
+        str commodity = "???????????????"
+        void textelite.next_input(commodity)
+        ubyte ci = elite_market.match(commodity)
+        if ci & 128 !=0 {
+            txt.print("Unknown\n")
+        } else {
+            ;txt.print("\nHow much? ")
+            void textelite.next_input(input)
+            ubyte amount = conv.str2ubyte(input)
+            if elite_market.current_quantity[ci] < amount {
+                txt.print(" Insufficient supply!\n")
+            } else {
+                uword price = elite_market.current_price[ci] * amount
+                ;txt.print(" Total price: ")
+                ;elite_util.print_10s(price)
+                if price > elite_ship.cash {
+                    txt.print(" Not enough cash!\n")
+                } else {
+                    elite_ship.cash -= price
+                    elite_ship.cargohold[ci] += amount
+                    elite_market.current_quantity[ci] -= amount
+                }
+            }
+        }
+    }
+
+    sub do_sell() {
+        ;txt.print("\nSell what commodity? ")
+        str commodity = "???????????????"
+        void textelite.next_input(commodity)
+        ubyte ci = elite_market.match(commodity)
+        if ci & 128 !=0 {
+            txt.print("Unknown\n")
+        } else {
+            ;txt.print("\nHow much? ")
+            void textelite.next_input(input)
+            ubyte amount = conv.str2ubyte(input)
+            if elite_ship.cargohold[ci] < amount {
+                txt.print(" Insufficient supply!\n")
+            } else {
+                uword price = elite_market.current_price[ci] * amount
+                ;txt.print(" Total price: ")
+                ;elite_util.print_10s(price)
+                elite_ship.cash += price
+                elite_ship.cargohold[ci] -= amount
+                elite_market.current_quantity[ci] += amount
+            }
+        }
+    }
+
+    sub do_fuel() {
+        ;txt.print("\nBuy fuel. Amount? ")
+        void textelite.next_input(input)
+        ubyte buy_fuel = 10*conv.str2ubyte(input)
+        ubyte max_fuel = elite_ship.Max_fuel - elite_ship.fuel
+        if buy_fuel > max_fuel
+            buy_fuel = max_fuel
+        uword price = buy_fuel as uword * elite_ship.Fuel_cost
+        if price > elite_ship.cash {
+            txt.print("Not enough cash!\n")
+        } else {
+            elite_ship.cash -= price
+            elite_ship.fuel += buy_fuel
+        }
+    }
+
+    sub do_cash() {
+        ;txt.print("\nCheat! Set cash amount: ")
+        void textelite.next_input(input)
+        elite_ship.cash = conv.str2uword(input)
+    }
+
+    sub do_hold() {
+        ;txt.print("\nCheat! Set cargohold size: ")
+        void textelite.next_input(input)
+        elite_ship.Max_cargo = conv.str2ubyte(input)
+    }
+
+    sub do_next_galaxy() {
+        txt.print("\n>>>>> Galaxy Hyperjump!\n")
+        elite_galaxy.travel_to(elite_galaxy.number+1, elite_planet.number)
+        elite_planet.display(false, 0)
+    }
+
+    sub do_info() {
+        ;txt.print("\nSystem name (empty=current): ")
+        num_chars = textelite.next_input(input)
+        if num_chars!=0 {
+            ubyte current_planet = elite_planet.number
+            ubyte x = elite_planet.x
+            ubyte y = elite_planet.y
+            if elite_galaxy.search_closest_planet(input) {
+                ubyte distance = elite_planet.distance(x, y)
+                elite_planet.display(false, distance)
+            } else {
+                ;txt.print(" Not found!")
+            }
+            elite_galaxy.travel_to(elite_galaxy.number, current_planet)
+        } else {
+            elite_planet.display(false, 0)
+        }
+    }
+
+    sub do_local() {
+        elite_galaxy.local_area()
+    }
+
+    sub do_map() {
+        ;txt.print("\n(l)ocal or (g)alaxy starmap? ")
+        num_chars = textelite.next_input(input)
+        if num_chars!=0 {
+            elite_galaxy.starmap(input[0]=='l')
+        }
+    }
+
+    sub do_show_market() {
+        elite_market.display()
+        ;txt.print("\nFuel: ")
+        ;elite_util.print_10s(elite_ship.fuel)
+        ;txt.print("   Cargohold space: ")
+        ;txt.print_ub(elite_ship.cargo_free())
+        ;txt.print("t\n")
+    }
+}
+
+elite_ship {
+    const ubyte Max_fuel = 70
+    const ubyte Fuel_cost = 2
+    ubyte Max_cargo = 20
+
+    ubyte fuel
+    uword cash
+    ubyte[17] cargohold
+
+    sub init() {
+        sys.memset(cargohold, len(cargohold), 0)
+        fuel = Max_fuel
+        cash = 1000
+    }
+}
+
+elite_market {
+    ubyte[17] baseprices = [$13, $14, $41, $28, $53, $C4, $EB, $9A, $75, $4E, $7C, $B0, $20, $61, $AB, $2D, $35]
+    byte[17] gradients = [-$02, -$01, -$03, -$05, -$05, $08, $1D, $0E, $06, $01, $0d, -$09, -$01, -$01, -$02, -$01, $0F]
+    ubyte[17] basequants = [$06, $0A, $02, $E2, $FB, $36, $08, $38, $28, $11, $1D, $DC, $35, $42, $37, $FA, $C0]
+    ubyte[17] maskbytes = [$01, $03, $07, $1F, $0F, $03, $78, $03, $07, $1F, $07, $3F, $03, $07, $1F, $0F, $07]
+    str[17] names = ["Food", "Textiles", "Radioactives", "Slaves", "Liquor/Wines", "Luxuries", "Narcotics", "Computers",
+                     "Machinery", "Alloys", "Firearms", "Furs", "Minerals", "Gold", "Platinum", "Gem-Stones", "Alien Items"]
+
+    ubyte[17] current_quantity
+    uword[17] current_price
+
+    sub init(ubyte fluct) {
+        ; Prices and availabilities are influenced by the planet's economy type
+        ; (0-7) and a random "fluctuation" byte that was kept within the saved
+        ; commander position to keep the market prices constant over gamesaves.
+        ; Availabilities must be saved with the game since the player alters them
+        ; by buying (and selling(?))
+        ;
+        ; Almost all commands are one byte only and overflow "errors" are
+        ; extremely frequent and exploited.
+        ;
+        ; Trade Item prices are held internally in a single byte=true value/4.
+        ; The decimal point in prices is introduced only when printing them.
+        ; Internally, all prices are integers.
+        ; The player's cash is held in four bytes.
+        ubyte ci
+        for ci in 0 to len(names)-1 {
+            word product
+            byte changing
+            product = elite_planet.economy as word * gradients[ci]
+            changing = fluct & maskbytes[ci]  as byte
+            ubyte q = (basequants[ci] as word + changing - product) as ubyte
+            if q & $80 !=0
+                q = 0  ; clip to positive 8-bit
+            current_quantity[ci] = q & $3f
+            q = (baseprices[ci] + changing + product) as ubyte
+            current_price[ci] = q * $0004
+        }
+        current_quantity[16] = 0        ; force nonavailability of Alien Items
+    }
+
+    sub display() {
+        return
+;        ubyte ci
+;        txt.nl()
+;        elite_planet.print_name_uppercase()
+;        txt.print(" trade market:\n    COMMODITY / PRICE / AVAIL / IN HOLD\n")
+;        for ci in 0 to len(names)-1 {
+;            elite_util.print_right(13, names[ci])
+;            txt.print("   ")
+;            elite_util.print_10s(current_price[ci])
+;            txt.column(24)
+;            txt.print_ub(current_quantity[ci])
+;            txt.chrout(' ')
+;            when units[ci] {
+;                0 -> txt.chrout('t')
+;                1 -> txt.print("kg")
+;                2 -> txt.chrout('g')
+;            }
+;            txt.column(32)
+;            txt.print_ub(elite_ship.cargohold[ci])
+;            txt.nl()
+;        }
+    }
+
+    sub match(uword nameptr) -> ubyte {
+        ubyte ci
+        for ci in 0 to len(names)-1 {
+            if elite_util.prefix_matches(nameptr, names[ci])
+                return ci
+        }
+        return 255
+    }
+}
+
+elite_galaxy {
+    const uword GALSIZE = 256
+    const uword base0 = $5A4A       ; seeds for the first galaxy
+    const uword base1 = $0248
+    const uword base2 = $B753
+
+    str pn_pairs = "..lexegezacebisousesarmaindirea.eratenberalavetiedorquanteisrion"
+
+    ubyte number
+
+    uword[3] seed
+
+    sub init(ubyte galaxynum) {
+        number = 1
+        elite_planet.number = 255
+        seed[0] = base0
+        seed[1] = base1
+        seed[2] = base2
+        repeat galaxynum-1 {
+            nextgalaxy()
+        }
+    }
+
+    sub nextgalaxy() {
+        textelite.num_commands++
+
+        seed[0] = twist(seed[0])
+        seed[1] = twist(seed[1])
+        seed[2] = twist(seed[2])
+        number++
+        if number==9
+            number = 1
+    }
+
+    sub travel_to(ubyte galaxynum, ubyte system) {
+        init(galaxynum)
+        generate_next_planet()   ; always at least planet 0  (separate to avoid repeat ubyte overflow)
+        repeat system {
+            generate_next_planet()
+            textelite.num_commands++
+        }
+        elite_planet.name = make_current_planet_name()
+        init_market_for_planet()
+    }
+
+    sub init_market_for_planet() {
+        elite_market.init(lsb(seed[0])+msb(seed[2]))
+    }
+
+    sub search_closest_planet(uword nameptr) -> bool {
+        textelite.num_commands++
+
+        ubyte x = elite_planet.x
+        ubyte y = elite_planet.y
+        ubyte current_planet_num = elite_planet.number
+
+        init(number)
+        bool found = false
+        ubyte current_closest_pi
+        ubyte current_distance = 127
+        ubyte pi
+        for pi in 0 to 255 {
+            generate_next_planet()
+            elite_planet.name = make_current_planet_name()
+            if elite_util.prefix_matches(nameptr, elite_planet.name) {
+                ubyte distance = elite_planet.distance(x, y)
+                if distance < current_distance {
+                    current_distance = distance
+                    current_closest_pi = pi
+                    found = true
+                }
+            }
+        }
+
+        if found
+            travel_to(number, current_closest_pi)
+        else
+            travel_to(number, current_planet_num)
+
+        return found
+    }
+
+    sub local_area() {
+        ubyte current_planet = elite_planet.number
+        ubyte px = elite_planet.x
+        ubyte py = elite_planet.y
+        ubyte pn = 0
+
+        init(number)
+;        txt.print("\nGalaxy #")
+;        txt.print_ub(number)
+;        txt.print(" - systems in vicinity:\n")
+        do {
+            generate_next_planet()
+            ubyte distance = elite_planet.distance(px, py)
+            if distance <= elite_ship.Max_fuel {
+;                if distance <= elite_ship.fuel
+;                    txt.chrout('*')
+;                else
+;                    txt.chrout('-')
+;                txt.spc()
+                elite_planet.name = make_current_planet_name()
+                elite_planet.display(true, distance)
+            }
+            pn++
+        } until pn==0
+
+        travel_to(number, current_planet)
+    }
+
+    sub starmap(bool local) {
+        ubyte current_planet = elite_planet.number
+        ubyte px = elite_planet.x
+        ubyte py = elite_planet.y
+        str current_name = "        "       ; 8 max
+        ubyte pn = 0
+
+        current_name = elite_planet.name
+        init(number)
+;        txt.clear_screen()
+;        txt.print("Galaxy #")
+;        txt.print_ub(number)
+;        if local
+;            txt.print(" - local systems")
+;        else
+;            txt.print(" - galaxy")
+;        txt.print(" starmap:\n")
+        ubyte max_distance = 255
+        if local
+            max_distance = elite_ship.Max_fuel
+        ubyte home_sx
+        ubyte home_sy
+        ubyte home_distance
+
+        do {
+            generate_next_planet()
+            ubyte distance = elite_planet.distance(px, py)
+            if distance <= max_distance {
+                elite_planet.name = make_current_planet_name()
+                elite_planet.name[0] = strings.upperchar(elite_planet.name[0])
+                uword tx = elite_planet.x
+                uword ty = elite_planet.y
+                if local {
+                    tx = tx + 24 - px
+                    ty = ty + 24 - py
+                }
+                ubyte sx = display_scale_x(tx)
+                ubyte sy = display_scale_y(ty)
+                ubyte char = '*'
+                if elite_planet.number==current_planet
+                    char = '%'
+                if local {
+                    print_planet_details(elite_planet.name, sx, sy, distance)
+                } else if elite_planet.number==current_planet {
+                    home_distance = distance
+                    home_sx = sx
+                    home_sy = sy
+                }
+                ; txt.setchr(2+sx, 2+sy, char)
+            }
+            pn++
+        } until pn==0
+
+        if not local
+            print_planet_details(current_name, home_sx, home_sy, home_distance)
+
+;        if local
+;            txt.plot(0, display_scale_y(64) + 4)
+;        else
+;            txt.plot(0, display_scale_y(256) + 4 as ubyte)
+        travel_to(number, current_planet)
+
+        sub print_planet_details(str name, ubyte screenx, ubyte screeny, ubyte d) {
+            return
+;            txt.plot(2+screenx-2, 2+screeny+1)
+;            txt.print(name)
+;            if d!=0 {
+;                txt.plot(2+screenx-2, 2+screeny+2)
+;                elite_util.print_10s(d)
+;                txt.print(" LY")
+;            }
+        }
+
+        sub display_scale_x(uword x) -> ubyte {
+            if local
+                return x/2 as ubyte
+            return x/8 as ubyte
+        }
+
+        sub display_scale_y(uword y) -> ubyte {
+            if local
+                return y/4 as ubyte
+            return y/16 as ubyte
+        }
+    }
+
+    ubyte pn_pair1
+    ubyte pn_pair2
+    ubyte pn_pair3
+    ubyte pn_pair4
+    bool longname
+
+    sub generate_next_planet() {
+        determine_planet_properties()
+        longname = lsb(seed[0]) & 64 !=0
+
+        ; Always four iterations of random number
+        pn_pair1 = (msb(seed[2]) & 31) * 2
+        tweakseed()
+        pn_pair2 = (msb(seed[2]) & 31) * 2
+        tweakseed()
+        pn_pair3 = (msb(seed[2]) & 31) * 2
+        tweakseed()
+        pn_pair4 = (msb(seed[2]) & 31) * 2
+        tweakseed()
+    }
+
+    sub make_current_planet_name() -> str {
+        ubyte ni = 0
+        str name = "         "    ; max 8
+
+        if pn_pairs[pn_pair1] != '.' {
+            name[ni] = pn_pairs[pn_pair1]
+            ni++
+        }
+        if pn_pairs[pn_pair1+1] != '.' {
+            name[ni] = pn_pairs[pn_pair1+1]
+            ni++
+        }
+        if pn_pairs[pn_pair2] != '.' {
+            name[ni] = pn_pairs[pn_pair2]
+            ni++
+        }
+        if pn_pairs[pn_pair2+1] != '.' {
+            name[ni] = pn_pairs[pn_pair2+1]
+            ni++
+        }
+        if pn_pairs[pn_pair3] != '.' {
+            name[ni] = pn_pairs[pn_pair3]
+            ni++
+        }
+        if pn_pairs[pn_pair3+1] != '.' {
+            name[ni] = pn_pairs[pn_pair3+1]
+            ni++
+        }
+
+        if longname {
+            if pn_pairs[pn_pair4] != '.' {
+                name[ni] = pn_pairs[pn_pair4]
+                ni++
+            }
+            if pn_pairs[pn_pair4+1] != '.' {
+                name[ni] = pn_pairs[pn_pair4+1]
+                ni++
+            }
+        }
+
+        name[ni] = 0
+        return name
+    }
+
+    sub determine_planet_properties() {
+        ; create the planet's characteristics
+        elite_planet.number++
+        elite_planet.x = msb(seed[1])
+        elite_planet.y = msb(seed[0])
+        elite_planet.govtype = lsb(seed[1]) >> 3 & 7  ; bits 3,4 &5 of w1
+        elite_planet.economy = msb(seed[0]) & 7  ; bits 8,9 &A of w0
+        if elite_planet.govtype <= 1
+            elite_planet.economy = (elite_planet.economy | 2)
+        elite_planet.techlevel = (msb(seed[1]) & 3) + (elite_planet.economy ^ 7)
+        elite_planet.techlevel += elite_planet.govtype >> 1
+        if elite_planet.govtype & 1 !=0
+            elite_planet.techlevel++
+        elite_planet.population = 4 * elite_planet.techlevel + elite_planet.economy
+        elite_planet.population += elite_planet.govtype + 1
+        elite_planet.productivity = ((elite_planet.economy ^ 7) + 3) * (elite_planet.govtype + 4)
+        elite_planet.productivity *= elite_planet.population * 8
+        ubyte seed2_msb = msb(seed[2])
+        elite_planet.radius = mkword((seed2_msb & 15) + 11, elite_planet.x)
+        elite_planet.species_is_alien = lsb(seed[2]) & 128 !=0      ; bit 7 of w2_lo
+        if elite_planet.species_is_alien {
+            elite_planet.species_size = (seed2_msb >> 2) & 7      ; bits 2-4 of w2_hi
+            elite_planet.species_color = seed2_msb >> 5           ; bits 5-7 of w2_hi
+            elite_planet.species_look = (seed2_msb ^ msb(seed[1])) & 7   ;bits 0-2 of (w0_hi EOR w1_hi)
+            elite_planet.species_kind = (elite_planet.species_look + (seed2_msb & 3)) & 7      ;Add bits 0-1 of w2_hi to A from previous step, and take bits 0-2 of the result
+        }
+
+        elite_planet.goatsoup_seed[0] = lsb(seed[1])
+        elite_planet.goatsoup_seed[1] = msb(seed[1])
+        elite_planet.goatsoup_seed[2] = lsb(seed[2])
+        elite_planet.goatsoup_seed[3] = seed2_msb
+    }
+
+    sub tweakseed() {
+        uword temp = seed[0] + seed[1] + seed[2]
+        seed[0] = seed[1]
+        seed[1] = seed[2]
+        seed[2] = temp
+    }
+
+    sub twist(uword x) -> uword {
+        ubyte xh = msb(x)
+        ubyte xl = lsb(x)
+        xh <<= 1        ; make sure carry flag is not used on first shift!
+        rol(xl)
+        return mkword(xh, xl)
+    }
+}
+
+elite_planet {
+    str[] @nosplit words81 = ["fabled", "notable", "well known", "famous", "noted"]
+    str[] @nosplit words82 = ["very", "mildly", "most", "reasonably", ""]
+    str[] @nosplit words83 = ["ancient", "\x95", "great", "vast", "pink"]
+    str[] @nosplit words84 = ["\x9E \x9D plantations", "mountains", "\x9C", "\x94 forests", "oceans"]
+    str[] @nosplit words85 = ["shyness", "silliness", "mating traditions", "loathing of \x86", "love for \x86"]
+    str[] @nosplit words86 = ["food blenders", "tourists", "poetry", "discos", "\x8E"]
+    str[] @nosplit words87 = ["talking tree", "crab", "bat", "lobst", "\xB2"]
+    str[] @nosplit words88 = ["beset", "plagued", "ravaged", "cursed", "scourged"]
+    str[] @nosplit words89 = ["\x96 civil war", "\x9B \x98 \x99s", "a \x9B disease", "\x96 earthquakes", "\x96 solar activity"]
+    str[] @nosplit words8A = ["its \x83 \x84", "the \xB1 \x98 \x99", "its inhabitants' \x9A \x85", "\xA1", "its \x8D \x8E"]
+    str[] @nosplit words8B = ["juice", "brandy", "water", "brew", "gargle blasters"]
+    str[] @nosplit words8C = ["\xB2", "\xB1 \x99", "\xB1 \xB2", "\xB1 \x9B", "\x9B \xB2"]
+    str[] @nosplit words8D = ["fabulous", "exotic", "hoopy", "unusual", "exciting"]
+    str[] @nosplit words8E = ["cuisine", "night life", "casinos", "sit coms", " \xA1 "]
+    str[] @nosplit words8F = ["\xB0", "The planet \xB0", "The world \xB0", "This planet", "This world"]
+    str[] @nosplit words90 = ["n unremarkable", " boring", " dull", " tedious", " revolting"]
+    str[] @nosplit words91 = ["planet", "world", "place", "little planet", "dump"]
+    str[] @nosplit words92 = ["wasp", "moth", "grub", "ant", "\xB2"]
+    str[] @nosplit words93 = ["poet", "arts graduate", "yak", "snail", "slug"]
+    str[] @nosplit words94 = ["tropical", "dense", "rain", "impenetrable", "exuberant"]
+    str[] @nosplit words95 = ["funny", "wierd", "unusual", "strange", "peculiar"]
+    str[] @nosplit words96 = ["frequent", "occasional", "unpredictable", "dreadful", "deadly"]
+    str[] @nosplit words97 = ["\x82 \x81 for \x8A", "\x82 \x81 for \x8A and \x8A", "\x88 by \x89", "\x82 \x81 for \x8A but \x88 by \x89", "a\x90 \x91"]
+    str[] @nosplit words98 = ["\x9B", "mountain", "edible", "tree", "spotted"]
+    str[] @nosplit words99 = ["\x9F", "\xA0", "\x87oid", "\x93", "\x92"]
+    str[] @nosplit words9A = ["ancient", "exceptional", "eccentric", "ingrained", "\x95"]
+    str[] @nosplit words9B = ["killer", "deadly", "evil", "lethal", "vicious"]
+    str[] @nosplit words9C = ["parking meters", "dust clouds", "ice bergs", "rock formations", "volcanoes"]
+    str[] @nosplit words9D = ["plant", "tulip", "banana", "corn", "\xB2weed"]
+    str[] @nosplit words9E = ["\xB2", "\xB1 \xB2", "\xB1 \x9B", "inhabitant", "\xB1 \xB2"]
+    str[] @nosplit words9F = ["shrew", "beast", "bison", "snake", "wolf"]
+    str[] @nosplit wordsA0 = ["leopard", "cat", "monkey", "goat", "fish"]
+    str[] @nosplit wordsA1 = ["\x8C \x8B", "\xB1 \x9F \xA2", "its \x8D \xA0 \xA2", "\xA3 \xA4", "\x8C \x8B"]
+    str[] @nosplit wordsA2 = ["meat", "cutlet", "steak", "burgers", "soup"]
+    str[] @nosplit wordsA3 = ["ice", "mud", "Zero-G", "vacuum", "\xB1 ultra"]
+    str[] @nosplit wordsA4 = ["hockey", "cricket", "karate", "polo", "tennis"]
+
+    uword[] @shared wordlists = [
+        words81, words82, words83, words84, words85, words86, words87, words88,
+        words89, words8A, words8B, words8C, words8D, words8E, words8F, words90,
+        words91, words92, words93, words94, words95, words96, words97, words98,
+        words99, words9A, words9B, words9C, words9D, words9E, words9F, wordsA0,
+        wordsA1, wordsA2, wordsA3, wordsA4]
+
+    str pairs0 = "abouseitiletstonlonuthnoallexegezacebisousesarmaindirea.eratenbe"
+
+    ubyte[4] goatsoup_rnd = [0, 0, 0, 0]
+    ubyte[4] goatsoup_seed = [0, 0, 0, 0]
+
+    str name = "        "       ; 8 max
+    ubyte number                ; starts at 0 in new galaxy, then increases by 1 for each generated planet
+    ubyte x
+    ubyte y
+    ubyte economy
+    ubyte govtype
+    ubyte techlevel
+    ubyte population
+    uword productivity
+    uword radius
+    bool species_is_alien      ; otherwise "Human Colonials"
+    ubyte species_size
+    ubyte species_color
+    ubyte species_look
+    ubyte species_kind
+
+    sub set_seed(uword s1, uword s2) {
+        goatsoup_seed[0] = lsb(s1)
+        goatsoup_seed[1] = msb(s1)
+        goatsoup_seed[2] = lsb(s2)
+        goatsoup_seed[3] = msb(s2)
+        reset_rnd()
+    }
+
+    sub reset_rnd() {
+        goatsoup_rnd[0] = goatsoup_seed[0]
+        goatsoup_rnd[1] = goatsoup_seed[1]
+        goatsoup_rnd[2] = goatsoup_seed[2]
+        goatsoup_rnd[3] = goatsoup_seed[3]
+    }
+
+    sub random_name() -> str {
+        ubyte ii
+        str randname = "        "       ; 8 chars max
+        ubyte nx = 0
+        for ii in 0 to goatsoup_rnd_number() & 3 {
+            ubyte xx = goatsoup_rnd_number() & $3e
+            if pairs0[xx] != '.' {
+                randname[nx] = pairs0[xx]
+                nx++
+            }
+            xx++
+            if pairs0[xx] != '.' {
+                randname[nx] = pairs0[xx]
+                nx++
+            }
+        }
+        randname[nx] = 0
+        randname[0] = strings.upperchar(randname[0])
+        return randname
+    }
+
+    sub goatsoup_rnd_number() -> ubyte {
+        ubyte xx = goatsoup_rnd[0] * 2
+        uword a = xx as uword + goatsoup_rnd[2]
+        if goatsoup_rnd[0] > 127
+            a ++
+        goatsoup_rnd[0] = lsb(a)
+        goatsoup_rnd[2] = xx
+        xx = goatsoup_rnd[1]
+        ubyte ac = xx + goatsoup_rnd[3] + msb(a)
+        goatsoup_rnd[1] = ac
+        goatsoup_rnd[3] = xx
+        return ac
+    }
+
+    sub distance(ubyte px, ubyte py) -> ubyte {
+        uword ax
+        uword ay
+        if px>x
+            ax=px-x
+        else
+            ax=x-px
+        if py>y
+            ay=py-y
+        else
+            ay=y-py
+        ay /= 2
+        ubyte d = sqrt(ax*ax + ay*ay)
+        if d>63
+            return 255
+        return d*4
+    }
+
+    sub soup() -> str {
+        str planet_result = " " * 160
+        uword[6] source_stack
+        ubyte stack_ptr = 0
+        str start_source = "\x8F is \x97."
+        uword source_ptr = &start_source
+        uword result_ptr = &planet_result
+
+        reset_rnd()
+        recursive_soup()
+        return planet_result
+
+        sub recursive_soup() {
+            repeat {
+                ubyte c = @(source_ptr)
+                source_ptr++
+                if c == $00 {
+                    @(result_ptr) = 0
+                    return
+                }
+                else if c <= $80 {
+                    @(result_ptr) = c
+                    result_ptr++
+                }
+                else {
+                    if c <= $a4 {
+                        ubyte rnr = goatsoup_rnd_number()
+                        ubyte wordNr = ((rnr >= $33) as ubyte) + ((rnr >= $66) as ubyte) + ((rnr >= $99) as ubyte) + ((rnr >= $CC) as ubyte)
+                        source_stack[stack_ptr] = source_ptr
+                        stack_ptr++
+                        source_ptr = getword(c, wordNr)
+                        recursive_soup()    ; RECURSIVE CALL - ignore the warning message from the compiler; we don't use local variables or parameters so we're safe in this case
+                        stack_ptr--
+                        source_ptr = source_stack[stack_ptr]
+                    } else {
+                        if c == $b0 {
+                            @(result_ptr) = strings.upperchar(name[0])
+                            result_ptr++
+                            concat_string(&name + 1)
+                        }
+                        else if c == $b1 {
+                            @(result_ptr) = strings.upperchar(name[0])
+                            result_ptr++
+                            ubyte ni
+                            for ni in 1 to len(name) {
+                                ubyte cc = name[ni]
+                                if cc in ['e', 'o', 0]
+                                    break
+                                else {
+                                    @(result_ptr) = cc
+                                    result_ptr++
+                                }
+                            }
+                            @(result_ptr) = 'i'
+                            result_ptr++
+                            @(result_ptr) = 'a'
+                            result_ptr++
+                            @(result_ptr) = 'n'
+                            result_ptr++
+                        }
+                        else if c == $b2 {
+                            concat_string(random_name())
+                        }
+                        else {
+                            @(result_ptr) = c
+                            result_ptr++
+                        }
+                    }
+                }
+            }
+        }
+
+        sub concat_string(uword str_ptr) {
+            repeat {
+                ubyte c = @(str_ptr)
+                if c==0
+                    break
+                else {
+                    @(result_ptr) = c
+                    str_ptr++
+                    result_ptr++
+                }
+            }
+        }
+    }
+
+    sub display(bool compressed, ubyte distance) {
+        txt.print(soup())
+        txt.nl()
+    }
+
+    sub getword(ubyte listnum, ubyte wordidx) -> uword {
+        uword list = wordlists[listnum-$81]
+        return peekw(list + wordidx*2)
+    }
+}
+
+elite_util {
+    sub prefix_matches(uword prefixptr, uword stringptr) -> bool {
+        repeat {
+            ubyte pc = @(prefixptr)
+            ubyte sc = @(stringptr)
+            if pc == 0
+                return true
+            ; to lowercase for case insensitive compare:
+            if strings.lowerchar(pc)!=strings.lowerchar(sc)
+                return false
+            prefixptr++
+            stringptr++
+        }
+    }
+}

benchmark-program/benchmark.p8

@@ -0,0 +1,117 @@
+
+;  This benchmark program is meant to check for regressions in the
+;  Prog8 compiler's code-generator (performance wise).
+;
+;  As the X16 computer is a more or less fixed system, it's not very useful
+;  to benchmark the computer itself with.
+
+
+%import textio
+%import b_adpcm
+%import b_circles
+%import b_3d
+%import b_life
+%import b_mandelbrot
+%import b_queens
+%import b_textelite
+%import b_maze
+%import b_sprites
+
+%zeropage basicsafe
+%option no_sysinit
+
+
+main {
+
+    str[20] benchmark_names
+    uword[20] benchmark_score
+
+
+    sub start() {
+        ubyte benchmark_number
+
+        cx16.set_screen_mode(3)
+        txt.color2(1, 6)
+        txt.clear_screen()
+
+        txt.print("\n\n\n  prog8 compiler benchmark tests.\n")
+        sys.wait(60)
+
+        benchmark_number = 0
+
+        announce_benchmark("maze solver")
+        benchmark_score[benchmark_number]  = maze.bench(300)
+        benchmark_number++
+
+        announce_benchmark("n-queens")
+        benchmark_score[benchmark_number]  = queens.bench(300)
+        benchmark_number++
+
+        announce_benchmark("mandelbrot (floating point)")
+        benchmark_score[benchmark_number]  = mandelbrot.calc(400)
+        benchmark_number++
+
+        announce_benchmark("game of life")
+        benchmark_score[benchmark_number]  = life.benchmark(300)
+        benchmark_number++
+
+        announce_benchmark("3d model rotation")
+        benchmark_score[benchmark_number]  = rotate3d.benchmark(300)
+        benchmark_number++
+
+        announce_benchmark("adpcm audio decoding")
+        benchmark_score[benchmark_number]  = adpcm.decode_benchmark(300)
+        benchmark_number++
+
+        announce_benchmark("circles with gfx_lores")
+        benchmark_score[benchmark_number]  = circles.draw(false, 300)
+        benchmark_number++
+
+;        announce_benchmark("circles with kernal")
+;        benchmark_score[benchmark_number]  = circles.draw(true, 300)
+;        benchmark_number++
+
+        announce_benchmark("text-elite")
+        benchmark_score[benchmark_number]  = textelite.bench(120)
+        benchmark_number++
+
+        announce_benchmark("sprites-coroutines-defer")
+        benchmark_score[benchmark_number]  = animsprites.benchmark(300)
+        benchmark_number++
+
+        benchmark_names[benchmark_number] = 0
+        benchmark_score[benchmark_number] = 0
+
+        cx16.set_screen_mode(3)
+        txt.uppercase()
+        txt.color2(1, 6)
+        uword final_score
+        benchmark_number = 0
+        txt.print("\nscore benchmark\n\n")
+        do {
+            txt.spc()
+            txt.print_uw(benchmark_score[benchmark_number])
+            txt.column(6)
+            txt.print(benchmark_names[benchmark_number])
+            final_score += benchmark_score[benchmark_number]
+            txt.nl()
+            benchmark_number++
+        } until benchmark_names[benchmark_number]==0
+
+        txt.print("\n\nfinal score : ")
+        txt.print_uw(final_score)
+        txt.nl()
+
+        sub announce_benchmark(str name) {
+            benchmark_names[benchmark_number] = name
+            cx16.set_screen_mode(3)
+            txt.uppercase()
+            txt.color2(1, 6)
+            txt.clear_screen()
+            txt.plot(4, 6)
+            txt.print(benchmark_names[benchmark_number])
+            txt.nl()
+            sys.wait(60)
+        }
+    }
+}

build.gradle

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

build.gradle.kts

@@ -0,0 +1,34 @@
+import org.jetbrains.kotlin.gradle.dsl.JvmTarget
+import org.jetbrains.kotlin.gradle.internal.config.LanguageFeature
+
+
+plugins {
+    kotlin("jvm") version "2.1.20"
+}
+
+allprojects {
+    apply(plugin="kotlin")
+
+    repositories {
+        mavenLocal()
+        mavenCentral()
+    }
+
+    kotlin {
+        compilerOptions {
+            freeCompilerArgs = listOf("-Xwhen-guards")
+            jvmTarget = JvmTarget.JVM_11
+        }
+        sourceSets.all {
+            languageSettings {
+                // enable language features like so:
+                // enableLanguageFeature(LanguageFeature.WhenGuards.name)
+            }
+        }
+    }
+
+    java {
+        targetCompatibility = JavaVersion.VERSION_11
+        sourceCompatibility = JavaVersion.VERSION_11
+    }
+}

codeCore/build.gradle.kts

@@ -0,0 +1,24 @@
+import org.jetbrains.kotlin.gradle.dsl.JvmTarget
+
+plugins {
+    kotlin("jvm")
+}
+
+dependencies {
+    // should have no dependencies to other modules
+    // implementation("org.jetbrains.kotlin:kotlin-stdlib-jdk8")
+    implementation("com.michael-bull.kotlin-result:kotlin-result-jvm:2.0.1")
+}
+
+sourceSets {
+    main {
+        java {
+            srcDir("${project.projectDir}/src")
+        }
+        resources {
+            srcDir("${project.projectDir}/res")
+        }
+    }
+}
+
+// note: there are no unit tests in this module!

codeCore/codeCore.iml

@@ -10,7 +10,5 @@
     <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" />
   </component>
 </module>

codeCore/src/prog8/code/Globals.kt

@@ -0,0 +1,31 @@
+package prog8.code
+
+import java.io.IOException
+import java.nio.file.Path
+import kotlin.io.path.absolute
+
+
+// the automatically generated module where all string literals are interned to:
+const val INTERNED_STRINGS_MODULENAME = "prog8_interned_strings"
+
+// all automatically generated labels everywhere need to have the same label name prefix:
+const val GENERATED_LABEL_PREFIX = "p8_label_gen_"
+
+
+/**
+ * Returns the absolute path of the given path,
+ * where links are replaced by the actual directories,
+ * and containing no redundant path elements.
+ * If the path doesn't refer to an existing directory or file on the file system,
+ * it is returned unchanged.
+ */
+fun Path.sanitize(): Path {
+    return try {
+        this.toRealPath().normalize()
+    } catch (_: java.nio.file.NoSuchFileException) {
+        this.absolute().normalize()
+        //throw NoSuchFileException(this.toFile(), null, nx.reason).also { it.initCause(nx) }
+    } catch (iox: IOException) {
+        throw FileSystemException(this.toFile()).also { it.initCause(iox) }
+    }
+}

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

@@ -0,0 +1,152 @@
+package prog8.code.core
+
+class ReturnConvention(val dt: BaseDataType?, val reg: RegisterOrPair?)
+class ParamConvention(val dt: BaseDataType, val reg: RegisterOrPair?, val variable: Boolean)
+class CallConvention(val params: List<ParamConvention>, val returns: ReturnConvention) {
+    override fun toString(): String {
+        val paramConvs =  params.mapIndexed { index, it ->
+            when {
+                it.reg!=null -> "$index:${it.reg}"
+                it.variable -> "$index:variable"
+                else -> "$index:???"
+            }
+        }
+        val returnConv =
+            when {
+                returns.reg == RegisterOrPair.FAC1 -> "floatFAC1"
+                returns.reg != null -> returns.reg.toString()
+                else -> "<no returnvalue>"
+            }
+        return "CallConvention[" + paramConvs.joinToString() + " ; returns: $returnConv]"
+    }
+}
+
+class FParam(val name: String, vararg val possibleDatatypes: BaseDataType)
+
+
+private val IterableDatatypes = arrayOf(BaseDataType.STR, BaseDataType.ARRAY, BaseDataType.ARRAY_SPLITW)
+private val IntegerDatatypes = arrayOf(BaseDataType.UBYTE, BaseDataType.BYTE, BaseDataType.UWORD, BaseDataType.WORD, BaseDataType.LONG)
+private val NumericDatatypes = arrayOf(BaseDataType.UBYTE, BaseDataType.BYTE, BaseDataType.UWORD, BaseDataType.WORD, BaseDataType.LONG, BaseDataType.FLOAT)
+
+
+class FSignature(val pure: Boolean,      // does it have side effects?
+                 val returnType: BaseDataType?,
+                 vararg val parameters: FParam) {
+
+    fun callConvention(actualParamTypes: List<BaseDataType>): CallConvention {
+        val returns: ReturnConvention = when (returnType) {
+            BaseDataType.UBYTE, BaseDataType.BYTE -> ReturnConvention(returnType, RegisterOrPair.A)
+            BaseDataType.UWORD, BaseDataType.WORD -> ReturnConvention(returnType, RegisterOrPair.AY)
+            BaseDataType.FLOAT -> ReturnConvention(returnType, RegisterOrPair.FAC1)
+            in IterableDatatypes -> ReturnConvention(returnType!!, RegisterOrPair.AY)
+            null -> ReturnConvention(null, null)
+            else -> {
+                // return type depends on arg type
+                when (val paramType = actualParamTypes.first()) {
+                    BaseDataType.UBYTE, BaseDataType.BYTE -> ReturnConvention(paramType, RegisterOrPair.A)
+                    BaseDataType.UWORD, BaseDataType.WORD -> ReturnConvention(paramType, RegisterOrPair.AY)
+                    BaseDataType.FLOAT -> ReturnConvention(paramType, RegisterOrPair.FAC1)
+                    in IterableDatatypes -> ReturnConvention(paramType, RegisterOrPair.AY)
+                    else -> ReturnConvention(paramType, null)
+                }
+            }
+        }
+
+        return when {
+            actualParamTypes.isEmpty() -> CallConvention(emptyList(), returns)
+            actualParamTypes.size==1 -> {
+                // One parameter goes via register/registerpair.
+                // this avoids repeated code for every caller to store the value in the subroutine's argument variable.
+                // (that store is still done, but only coded once at the start at the subroutine itself rather than at every call site).
+                val paramConv = when(val paramType = actualParamTypes[0]) {
+                    BaseDataType.UBYTE, BaseDataType.BYTE -> ParamConvention(paramType, RegisterOrPair.A, false)
+                    BaseDataType.UWORD, BaseDataType.WORD -> ParamConvention(paramType, RegisterOrPair.AY, false)
+                    BaseDataType.FLOAT -> ParamConvention(paramType, RegisterOrPair.AY, false)      // NOTE: for builtin functions, floating point arguments are passed by reference (so you get a pointer in AY)
+                    in IterableDatatypes -> ParamConvention(paramType, RegisterOrPair.AY, false)
+                    else -> ParamConvention(paramType, null, false)
+                }
+                CallConvention(listOf(paramConv), returns)
+            }
+            actualParamTypes.size==2 && (actualParamTypes[0].isByte && actualParamTypes[1].isWord) -> {
+                TODO("opportunity to pass word+byte arguments in A,Y and X registers but not implemented yet")
+            }
+            actualParamTypes.size==2 && (actualParamTypes[0].isWord && actualParamTypes[1].isByte) -> {
+                TODO("opportunity to pass word+byte arguments in A,Y and X registers but not implemented yet")
+            }
+            actualParamTypes.size==3 && actualParamTypes.all { it.isByte } -> {
+                TODO("opportunity to pass 3 byte arguments in A,Y and X registers but not implemented yet")
+            }
+            else -> {
+                // multiple parameters go via variables
+                val paramConvs = actualParamTypes.map { ParamConvention(it, null, true) }
+                CallConvention(paramConvs, returns)
+            }
+        }
+    }
+}
+
+val BuiltinFunctions: Map<String, FSignature> = mapOf(
+    "setlsb"  to FSignature(false, null, FParam("variable", BaseDataType.WORD, BaseDataType.UWORD), FParam("value", BaseDataType.BYTE, BaseDataType.UBYTE)),
+    "setmsb"  to FSignature(false, null, FParam("variable", BaseDataType.WORD, BaseDataType.UWORD), FParam("value", BaseDataType.BYTE, BaseDataType.UBYTE)),
+    "rol"     to FSignature(false, null, FParam("item", BaseDataType.UBYTE, BaseDataType.UWORD)),
+    "ror"     to FSignature(false, null, FParam("item", BaseDataType.UBYTE, BaseDataType.UWORD)),
+    "rol2"    to FSignature(false, null, FParam("item", BaseDataType.UBYTE, BaseDataType.UWORD)),
+    "ror2"    to FSignature(false, null, FParam("item", BaseDataType.UBYTE, BaseDataType.UWORD)),
+    "cmp"     to FSignature(false, null, FParam("value1", *IntegerDatatypes), FParam("value2", *NumericDatatypes)),  // cmp returns a status in the carry flag, but not a proper return value
+    "prog8_lib_stringcompare"     to FSignature(true, BaseDataType.BYTE, FParam("str1", BaseDataType.STR), FParam("str2", BaseDataType.STR)),
+    "prog8_lib_square_byte"       to FSignature(true, BaseDataType.UBYTE, FParam("value", BaseDataType.BYTE, BaseDataType.UBYTE)),
+    "prog8_lib_square_word"       to FSignature(true, BaseDataType.UWORD, FParam("value", BaseDataType.WORD, BaseDataType.UWORD)),
+    "abs"           to FSignature(true, null, FParam("value", *NumericDatatypes)),
+    "abs__byte"     to FSignature(true, BaseDataType.UBYTE, FParam("value", BaseDataType.BYTE)),
+    "abs__word"     to FSignature(true, BaseDataType.UWORD, FParam("value", BaseDataType.WORD)),
+    "abs__float"    to FSignature(true, BaseDataType.FLOAT, FParam("value", BaseDataType.FLOAT)),
+    "len"           to FSignature(true, BaseDataType.UWORD, FParam("values", *IterableDatatypes)),
+    "sizeof"        to FSignature(true, BaseDataType.UBYTE, FParam("object", *BaseDataType.entries.toTypedArray())),
+    "sgn"           to FSignature(true, BaseDataType.BYTE, FParam("value", *NumericDatatypes)),
+    "sqrt"          to FSignature(true, null, FParam("value", *NumericDatatypes)),
+    "sqrt__ubyte"   to FSignature(true, BaseDataType.UBYTE, FParam("value", BaseDataType.UBYTE)),
+    "sqrt__uword"   to FSignature(true, BaseDataType.UBYTE, FParam("value", BaseDataType.UWORD)),
+    "sqrt__float"   to FSignature(true, BaseDataType.FLOAT, FParam("value", BaseDataType.FLOAT)),
+    "divmod"        to FSignature(false, null, FParam("dividend", BaseDataType.UBYTE, BaseDataType.UWORD), FParam("divisor", BaseDataType.UBYTE, BaseDataType.UWORD), FParam("quotient", BaseDataType.UBYTE, BaseDataType.UWORD), FParam("remainder", BaseDataType.UBYTE, BaseDataType.UWORD)),
+    "divmod__ubyte" to FSignature(false, null, FParam("dividend", BaseDataType.UBYTE), FParam("divisor", BaseDataType.UBYTE), FParam("quotient", BaseDataType.UBYTE), FParam("remainder", BaseDataType.UBYTE)),
+    "divmod__uword" to FSignature(false, null, FParam("dividend", BaseDataType.UWORD), FParam("divisor", BaseDataType.UWORD), FParam("quotient", BaseDataType.UWORD), FParam("remainder", BaseDataType.UWORD)),
+    "lsb"           to FSignature(true, BaseDataType.UBYTE, FParam("value", BaseDataType.UWORD, BaseDataType.WORD, BaseDataType.LONG)),
+    "lsw"           to FSignature(true, BaseDataType.UWORD, FParam("value", BaseDataType.UWORD, BaseDataType.WORD, BaseDataType.LONG)),
+    "msb"           to FSignature(true, BaseDataType.UBYTE, FParam("value", BaseDataType.UWORD, BaseDataType.WORD, BaseDataType.LONG)),
+    "msw"           to FSignature(true, BaseDataType.UWORD, FParam("value", BaseDataType.UWORD, BaseDataType.WORD, BaseDataType.LONG)),
+    "mkword"        to FSignature(true, BaseDataType.UWORD, FParam("msb", BaseDataType.UBYTE), FParam("lsb", BaseDataType.UBYTE)),
+    "clamp"         to FSignature(true, null, FParam("value", BaseDataType.BYTE), FParam("minimum", BaseDataType.BYTE), FParam("maximum", BaseDataType.BYTE)),
+    "clamp__byte"   to FSignature(true, BaseDataType.BYTE, FParam("value", BaseDataType.BYTE), FParam("minimum", BaseDataType.BYTE), FParam("maximum", BaseDataType.BYTE)),
+    "clamp__ubyte"  to FSignature(true, BaseDataType.UBYTE, FParam("value", BaseDataType.UBYTE), FParam("minimum", BaseDataType.UBYTE), FParam("maximum", BaseDataType.UBYTE)),
+    "clamp__word"   to FSignature(true, BaseDataType.WORD, FParam("value", BaseDataType.WORD), FParam("minimum", BaseDataType.WORD), FParam("maximum", BaseDataType.WORD)),
+    "clamp__uword"  to FSignature(true, BaseDataType.UWORD, FParam("value", BaseDataType.UWORD), FParam("minimum", BaseDataType.UWORD), FParam("maximum", BaseDataType.UWORD)),
+    "min"           to FSignature(true, null, FParam("val1", BaseDataType.BYTE), FParam("val2", BaseDataType.BYTE)),
+    "min__byte"     to FSignature(true, BaseDataType.BYTE, FParam("val1", BaseDataType.BYTE), FParam("val2", BaseDataType.BYTE)),
+    "min__ubyte"    to FSignature(true, BaseDataType.UBYTE, FParam("val1", BaseDataType.UBYTE), FParam("val2", BaseDataType.UBYTE)),
+    "min__word"     to FSignature(true, BaseDataType.WORD, FParam("val1", BaseDataType.WORD), FParam("val2", BaseDataType.WORD)),
+    "min__uword"    to FSignature(true, BaseDataType.UWORD, FParam("val1", BaseDataType.UWORD), FParam("val2", BaseDataType.UWORD)),
+    "max"           to FSignature(true, null, FParam("val1", BaseDataType.BYTE), FParam("val2", BaseDataType.BYTE)),
+    "max__byte"     to FSignature(true, BaseDataType.BYTE, FParam("val1", BaseDataType.BYTE), FParam("val2", BaseDataType.BYTE)),
+    "max__ubyte"    to FSignature(true, BaseDataType.UBYTE, FParam("val1", BaseDataType.UBYTE), FParam("val2", BaseDataType.UBYTE)),
+    "max__word"     to FSignature(true, BaseDataType.WORD, FParam("val1", BaseDataType.WORD), FParam("val2", BaseDataType.WORD)),
+    "max__uword"    to FSignature(true, BaseDataType.UWORD, FParam("val1", BaseDataType.UWORD), FParam("val2", BaseDataType.UWORD)),
+    "peek"          to FSignature(true, BaseDataType.UBYTE, FParam("address", BaseDataType.UWORD)),
+    "peekw"         to FSignature(true, BaseDataType.UWORD, FParam("address", BaseDataType.UWORD)),
+    "peekf"         to FSignature(true, BaseDataType.FLOAT, FParam("address", BaseDataType.UWORD)),
+    "poke"          to FSignature(false, null, FParam("address", BaseDataType.UWORD), FParam("value", BaseDataType.UBYTE)),
+    "pokew"         to FSignature(false, null, FParam("address", BaseDataType.UWORD), FParam("value", BaseDataType.UWORD)),
+    "pokef"         to FSignature(false, null, FParam("address", BaseDataType.UWORD), FParam("value", BaseDataType.FLOAT)),
+    "pokemon"       to FSignature(false, BaseDataType.UBYTE, FParam("address", BaseDataType.UWORD), FParam("value", BaseDataType.UBYTE)),
+    "rsave"         to FSignature(false, null),
+    "rrestore"      to FSignature(false, null),
+    "memory"        to FSignature(true, BaseDataType.UWORD, FParam("name", BaseDataType.STR), FParam("size", BaseDataType.UWORD), FParam("alignment", BaseDataType.UWORD)),
+    "callfar"       to FSignature(false, BaseDataType.UWORD, FParam("bank", BaseDataType.UBYTE), FParam("address", BaseDataType.UWORD), FParam("arg", BaseDataType.UWORD)),
+    "callfar2"      to FSignature(false, BaseDataType.UWORD, FParam("bank", BaseDataType.UBYTE), FParam("address", BaseDataType.UWORD), FParam("argA", BaseDataType.UBYTE), FParam("argX", BaseDataType.UBYTE), FParam("argY", BaseDataType.UBYTE), FParam("argC", BaseDataType.BOOL)),
+    "call"          to FSignature(false, BaseDataType.UWORD, FParam("address", BaseDataType.UWORD)),
+)
+
+val InplaceModifyingBuiltinFunctions = setOf(
+    "setlsb", "setmsb",
+    "rol", "ror", "rol2", "ror2",
+    "divmod", "divmod__ubyte", "divmod__uword"
+)

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

@@ -0,0 +1,45 @@
+package prog8.code.core
+
+import java.nio.file.Path
+import kotlin.io.path.Path
+
+
+class CompilationOptions(val output: OutputType,
+                         val launcher: CbmPrgLauncherType,
+                         val zeropage: ZeropageType,
+                         val zpReserved: List<UIntRange>,
+                         val zpAllowed: List<UIntRange>,
+                         val floats: Boolean,
+                         val noSysInit: Boolean,
+                         val romable: Boolean,
+                         val compTarget: ICompilationTarget,
+                         // these are set later, based on command line arguments or options in the source code:
+                         var loadAddress: UInt,
+                         var memtopAddress: UInt,
+                         var warnSymbolShadowing: Boolean = false,
+                         var optimize: Boolean = false,
+                         var asmQuiet: Boolean = false,
+                         var asmListfile: Boolean = false,
+                         var includeSourcelines: Boolean = false,
+                         var dumpVariables: Boolean = false,
+                         var dumpSymbols: Boolean = false,
+                         var experimentalCodegen: Boolean = false,
+                         var varsHighBank: Int? = null,
+                         var varsGolden: Boolean = false,
+                         var slabsHighBank: Int? = null,
+                         var slabsGolden: Boolean = false,
+                         var dontSplitWordArrays: Boolean = false,
+                         var breakpointCpuInstruction: String? = null,
+                         var ignoreFootguns: Boolean = false,
+                         var outputDir: Path = Path(""),
+                         var quiet: Boolean = false,
+                         var symbolDefs: Map<String, String> = emptyMap()
+) {
+    init {
+        compTarget.initializeMemoryAreas(this)
+    }
+
+    companion object {
+        val AllZeropageAllowed: List<UIntRange> = listOf(0u..255u)
+    }
+}

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

@@ -0,0 +1,97 @@
+package prog8.code.core
+
+import kotlin.math.abs
+import kotlin.math.pow
+
+val powersOfTwoFloat = (0..16).map { (2.0).pow(it) }.toTypedArray()
+val negativePowersOfTwoFloat = powersOfTwoFloat.map { -it }.toTypedArray()
+val powersOfTwoInt = (0..16).map { 2.0.pow(it).toInt() }.toTypedArray()
+
+fun Number.toHex(): String {
+    //  0..15 -> "0".."15"
+    //  16..255 -> "$10".."$ff"
+    //  256..65536 -> "$0100".."$ffff"
+    //  larger -> "$12345678"
+    // negative values are prefixed with '-'.
+    val integer = this.toInt()
+    if(integer<0)
+        return '-' + abs(integer).toHex()
+    return when (integer) {
+        in 0 until 16 -> integer.toString()
+        in 0 until 0x100 -> "$"+integer.toString(16).padStart(2,'0')
+        in 0 until 0x10000 -> "$"+integer.toString(16).padStart(4,'0')
+        else -> "$"+integer.toString(16).padStart(8,'0')
+    }
+}
+
+fun UInt.toHex(): String {
+    //  0..15 -> "0".."15"
+    //  16..255 -> "$10".."$ff"
+    //  256..65536 -> "$0100".."$ffff"
+    //  larger -> "$12345678"
+    return when (this) {
+        in 0u until 16u -> this.toString()
+        in 0u until 0x100u -> "$"+this.toString(16).padStart(2,'0')
+        in 0u until 0x10000u -> "$"+this.toString(16).padStart(4,'0')
+        else -> "$"+this.toString(16).padStart(8,'0')
+    }
+}
+
+fun Char.escape(): Char = this.toString().escape()[0]
+
+fun String.escape(): String {
+    val es = this.map {
+        when(it) {
+            '\t' -> "\\t"
+            '\n' -> "\\n"
+            '\r' -> "\\r"
+            '"' -> "\\\""
+            in '\u8000'..'\u80ff' -> "\\x" + (it.code - 0x8000).toString(16).padStart(2, '0')       // 'ugly' passthrough hack
+            in '\u0000'..'\u00ff' -> it.toString()
+            else -> "\\u" + it.code.toString(16).padStart(4, '0')
+        }
+    }
+    return es.joinToString("")
+}
+
+fun String.unescape(): String {
+    val result = mutableListOf<Char>()
+    val iter = this.iterator()
+    while(iter.hasNext()) {
+        val c = iter.nextChar()
+        if(c=='\\') {
+            val ec = iter.nextChar()
+            result.add(when(ec) {
+                '\\' -> '\\'
+                'n' -> '\n'
+                'r' -> '\r'
+                't' -> '\t'
+                '"' -> '"'
+                '\'' -> '\''
+                'u' -> {
+                    try {
+                        "${iter.nextChar()}${iter.nextChar()}${iter.nextChar()}${iter.nextChar()}".toInt(16).toChar()
+                    } catch (sb: StringIndexOutOfBoundsException) {
+                        throw IllegalArgumentException("invalid \\u escape sequence")
+                    } catch (nf: NumberFormatException) {
+                        throw IllegalArgumentException("invalid \\u escape sequence")
+                    }
+                }
+                'x' -> {
+                    try {
+                        val hex = ("" + iter.nextChar() + iter.nextChar()).toInt(16)
+                        (0x8000 + hex).toChar()         // 'ugly' pass-through hack
+                    } catch (sb: StringIndexOutOfBoundsException) {
+                        throw IllegalArgumentException("invalid \\x escape sequence")
+                    } catch (nf: NumberFormatException) {
+                        throw IllegalArgumentException("invalid \\x escape sequence")
+                    }
+                }
+                else -> throw IllegalArgumentException("invalid escape char in string: \\$ec")
+            })
+        } else {
+            result.add(c)
+        }
+    }
+    return result.joinToString("")
+}

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

@@ -0,0 +1,359 @@
+package prog8.code.core
+
+import java.util.*
+
+enum class BaseDataType {
+    UBYTE,              // pass by value            8 bits unsigned
+    BYTE,               // pass by value            8 bits signed
+    UWORD,              // pass by value            16 bits unsigned
+    WORD,               // pass by value            16 bits signed
+    LONG,               // pass by value            32 bits signed
+    FLOAT,              // pass by value            machine dependent
+    BOOL,               // pass by value            bit 0 of an 8-bit byte
+    STR,                // pass by reference
+    ARRAY,              // pass by reference, subtype is the element type
+    ARRAY_SPLITW,       // pass by reference, split word layout, subtype is the element type (restricted to word types)
+    UNDEFINED;
+
+
+    fun largerSizeThan(other: BaseDataType) =
+        when {
+            this == other -> false
+            this.isByteOrBool -> false
+            this.isWord -> other.isByteOrBool
+            this == LONG -> other.isByteOrBool || other.isWord
+            this == STR && other == UWORD || this == UWORD && other == STR -> false
+            this.isArray && other.isArray -> false
+            this.isArray -> other != FLOAT
+            this == STR -> other != FLOAT
+            else -> true
+        }
+
+    fun equalsSize(other: BaseDataType) =
+        when {
+            this == other -> true
+            this.isArray && other.isArray -> true
+            this.isByteOrBool -> other.isByteOrBool
+            this.isWord -> other.isWord
+            this == STR && other== UWORD || this== UWORD && other== STR -> true
+            this == STR && other.isArray -> true
+            this.isArray && other == STR -> true
+            else -> false
+        }
+}
+
+val BaseDataType.isByte get() = this in arrayOf(BaseDataType.UBYTE, BaseDataType.BYTE)
+val BaseDataType.isByteOrBool get() = this in arrayOf(BaseDataType.UBYTE, BaseDataType.BYTE, BaseDataType.BOOL)
+val BaseDataType.isWord get() = this in arrayOf(BaseDataType.UWORD, BaseDataType.WORD)
+val BaseDataType.isInteger get() = this in arrayOf(BaseDataType.UBYTE, BaseDataType.BYTE, BaseDataType.UWORD, BaseDataType.WORD, BaseDataType.LONG)
+val BaseDataType.isIntegerOrBool get() = this in arrayOf(BaseDataType.UBYTE, BaseDataType.BYTE, BaseDataType.UWORD, BaseDataType.WORD, BaseDataType.LONG, BaseDataType.BOOL)
+val BaseDataType.isNumeric get() = this == BaseDataType.FLOAT || this.isInteger
+val BaseDataType.isNumericOrBool get() = this == BaseDataType.BOOL || this.isNumeric
+val BaseDataType.isSigned get() = this in arrayOf(BaseDataType.BYTE, BaseDataType.WORD, BaseDataType.LONG, BaseDataType.FLOAT)
+val BaseDataType.isArray get() = this == BaseDataType.ARRAY || this == BaseDataType.ARRAY_SPLITW
+val BaseDataType.isSplitWordArray get() = this == BaseDataType.ARRAY_SPLITW
+val BaseDataType.isIterable get() =  this in arrayOf(BaseDataType.STR, BaseDataType.ARRAY, BaseDataType.ARRAY_SPLITW)
+val BaseDataType.isPassByRef get() = this.isIterable
+val BaseDataType.isPassByValue get() = !this.isIterable
+
+
+class DataType private constructor(val base: BaseDataType, val sub: BaseDataType?) {
+
+    init {
+        if(base.isArray) {
+            require(sub != null)
+            if(base.isSplitWordArray)
+                require(sub == BaseDataType.UWORD || sub == BaseDataType.WORD)
+        }
+        else if(base==BaseDataType.STR)
+            require(sub==BaseDataType.UBYTE) { "string subtype should be ubyte" }
+        else
+            require(sub == null) { "only string and array base types can have a subtype"}
+    }
+
+    override fun equals(other: Any?): Boolean {
+        if (this === other) return true
+        if (other !is DataType) return false
+        return base == other.base && sub == other.sub
+    }
+
+    override fun hashCode(): Int = Objects.hash(base, sub)
+
+    companion object {
+
+        val UBYTE = DataType(BaseDataType.UBYTE, null)
+        val BYTE = DataType(BaseDataType.BYTE, null)
+        val UWORD = DataType(BaseDataType.UWORD, null)
+        val WORD = DataType(BaseDataType.WORD, null)
+        val LONG = DataType(BaseDataType.LONG, null)
+        val FLOAT = DataType(BaseDataType.FLOAT, null)
+        val BOOL = DataType(BaseDataType.BOOL, null)
+        val STR = DataType(BaseDataType.STR, BaseDataType.UBYTE)
+        val UNDEFINED = DataType(BaseDataType.UNDEFINED, null)
+
+        private val simpletypes = mapOf(
+            BaseDataType.UBYTE to DataType(BaseDataType.UBYTE, null),
+            BaseDataType.BYTE to DataType(BaseDataType.BYTE, null),
+            BaseDataType.UWORD to DataType(BaseDataType.UWORD, null),
+            BaseDataType.WORD to DataType(BaseDataType.WORD, null),
+            BaseDataType.LONG to DataType(BaseDataType.LONG, null),
+            BaseDataType.FLOAT to DataType(BaseDataType.FLOAT, null),
+            BaseDataType.BOOL to DataType(BaseDataType.BOOL, null),
+            BaseDataType.STR to DataType(BaseDataType.STR, BaseDataType.UBYTE),
+            BaseDataType.UNDEFINED to DataType(BaseDataType.UNDEFINED, null)
+        )
+
+        fun forDt(dt: BaseDataType) = simpletypes.getValue(dt)
+
+        fun arrayFor(elementDt: BaseDataType, splitwordarray: Boolean=true): DataType {
+            val actualElementDt = if(elementDt==BaseDataType.STR) BaseDataType.UWORD else elementDt      // array of strings is actually just an array of UWORD pointers
+            return if(splitwordarray && actualElementDt.isWord)
+                DataType(BaseDataType.ARRAY_SPLITW, actualElementDt)
+            else {
+                if(actualElementDt.isNumericOrBool && actualElementDt != BaseDataType.LONG)
+                    DataType(BaseDataType.ARRAY, actualElementDt)
+                else
+                    throw NoSuchElementException("invalid element dt $elementDt")
+            }
+        }
+    }
+
+    fun elementToArray(splitwords: Boolean = true): DataType {
+        return if (base == BaseDataType.UWORD || base == BaseDataType.WORD || base == BaseDataType.STR) arrayFor(base, splitwords)
+        else arrayFor(base, false)
+    }
+
+    fun elementType(): DataType =
+        if(base.isArray || base==BaseDataType.STR)
+            forDt(sub!!)
+        else
+            throw IllegalArgumentException("not an array")
+
+    override fun toString(): String = when(base) {
+        BaseDataType.ARRAY -> {
+            when(sub) {
+                BaseDataType.BOOL -> "bool[]"
+                BaseDataType.FLOAT -> "float[]"
+                BaseDataType.BYTE -> "byte[]"
+                BaseDataType.WORD -> "word[]"
+                BaseDataType.UBYTE -> "ubyte[]"
+                BaseDataType.UWORD -> "uword[]"
+                else -> throw IllegalArgumentException("invalid sub type")
+            }
+        }
+        BaseDataType.ARRAY_SPLITW -> {
+            when(sub) {
+                BaseDataType.WORD -> "word[] (split)"
+                BaseDataType.UWORD -> "uword[] (split)"
+                else -> throw IllegalArgumentException("invalid sub type")
+            }
+        }
+        else -> base.name.lowercase()
+    }
+
+    fun sourceString(): String = when (base) {
+        BaseDataType.BOOL -> "bool"
+        BaseDataType.UBYTE -> "ubyte"
+        BaseDataType.BYTE -> "byte"
+        BaseDataType.UWORD -> "uword"
+        BaseDataType.WORD -> "word"
+        BaseDataType.LONG -> "long"
+        BaseDataType.FLOAT -> "float"
+        BaseDataType.STR -> "str"
+        BaseDataType.ARRAY -> {
+            when(sub) {
+                BaseDataType.UBYTE -> "ubyte["
+                BaseDataType.UWORD -> "@nosplit uword["
+                BaseDataType.BOOL -> "bool["
+                BaseDataType.BYTE -> "byte["
+                BaseDataType.WORD -> "@nosplit word["
+                BaseDataType.FLOAT -> "float["
+                else -> throw IllegalArgumentException("invalid sub type")
+            }
+        }
+        BaseDataType.ARRAY_SPLITW -> {
+            when(sub) {
+                BaseDataType.UWORD -> "uword["
+                BaseDataType.WORD -> "word["
+                else -> throw IllegalArgumentException("invalid sub type")
+            }
+        }
+        BaseDataType.UNDEFINED -> throw IllegalArgumentException("wrong dt")
+    }
+
+    // is the type assignable to the given other type (perhaps via a typecast) without loss of precision?
+    infix fun isAssignableTo(targetType: DataType) =
+        when(base) {
+            BaseDataType.BOOL -> targetType.base == BaseDataType.BOOL
+            BaseDataType.UBYTE -> targetType.base in arrayOf(BaseDataType.UBYTE, BaseDataType.WORD, BaseDataType.UWORD, BaseDataType.LONG, BaseDataType.FLOAT)
+            BaseDataType.BYTE -> targetType.base in arrayOf(BaseDataType.BYTE, BaseDataType.WORD, BaseDataType.LONG, BaseDataType.FLOAT)
+            BaseDataType.UWORD -> targetType.base in arrayOf(BaseDataType.UWORD, BaseDataType.LONG, BaseDataType.FLOAT)
+            BaseDataType.WORD -> targetType.base in arrayOf(BaseDataType.WORD, BaseDataType.LONG, BaseDataType.FLOAT)
+            BaseDataType.LONG -> targetType.base in arrayOf(BaseDataType.LONG, BaseDataType.FLOAT)
+            BaseDataType.FLOAT -> targetType.base in arrayOf(BaseDataType.FLOAT)
+            BaseDataType.STR -> targetType.base in arrayOf(BaseDataType.STR, BaseDataType.UWORD)
+            BaseDataType.ARRAY, BaseDataType.ARRAY_SPLITW -> targetType.base in arrayOf(BaseDataType.ARRAY, BaseDataType.ARRAY_SPLITW) && targetType.sub == sub
+            BaseDataType.UNDEFINED -> false
+        }
+
+    fun largerSizeThan(other: DataType): Boolean = base.largerSizeThan(other.base)
+    fun equalsSize(other: DataType): Boolean = base.equalsSize(other.base)
+
+    val isUndefined = base == BaseDataType.UNDEFINED
+    val isByte = base.isByte
+    val isUnsignedByte = base == BaseDataType.UBYTE
+    val isSignedByte = base == BaseDataType.BYTE
+    val isByteOrBool = base.isByteOrBool
+    val isWord = base.isWord
+    val isUnsignedWord =  base == BaseDataType.UWORD
+    val isSignedWord =  base == BaseDataType.WORD
+    val isInteger = base.isInteger
+    val isIntegerOrBool = base.isIntegerOrBool
+    val isNumeric = base.isNumeric
+    val isNumericOrBool = base.isNumericOrBool
+    val isSigned = base.isSigned
+    val isUnsigned = !base.isSigned
+    val isArray = base.isArray
+    val isBoolArray = base.isArray && sub == BaseDataType.BOOL
+    val isByteArray = base.isArray && (sub == BaseDataType.UBYTE || sub == BaseDataType.BYTE)
+    val isUnsignedByteArray = base.isArray && sub == BaseDataType.UBYTE
+    val isSignedByteArray = base.isArray && sub == BaseDataType.BYTE
+    val isWordArray = base.isArray && (sub == BaseDataType.UWORD || sub == BaseDataType.WORD)
+    val isUnsignedWordArray = base.isArray && sub == BaseDataType.UWORD
+    val isSignedWordArray = base.isArray && sub == BaseDataType.WORD
+    val isFloatArray = base.isArray && sub == BaseDataType.FLOAT
+    val isString = base == BaseDataType.STR
+    val isBool = base == BaseDataType.BOOL
+    val isFloat = base == BaseDataType.FLOAT
+    val isLong = base == BaseDataType.LONG
+    val isStringly = base == BaseDataType.STR || base == BaseDataType.UWORD || (base == BaseDataType.ARRAY && (sub == BaseDataType.UBYTE || sub == BaseDataType.BYTE))
+    val isSplitWordArray = base.isSplitWordArray
+    val isSplitUnsignedWordArray = base.isSplitWordArray && sub == BaseDataType.UWORD
+    val isSplitSignedWordArray = base.isSplitWordArray && sub == BaseDataType.WORD
+    val isIterable =  base.isIterable
+    val isPassByRef = base.isPassByRef
+    val isPassByValue = base.isPassByValue
+}
+
+
+enum class CpuRegister {
+    A,
+    X,
+    Y
+}
+
+enum class RegisterOrPair {
+    A,
+    X,
+    Y,
+    AX,
+    AY,
+    XY,
+    FAC1,
+    FAC2,
+    // cx16 virtual registers:
+    R0, R1, R2, R3, R4, R5, R6, R7,
+    R8, R9, R10, R11, R12, R13, R14, R15;
+
+    companion object {
+        val names by lazy { entries.map { it.toString()} }
+        fun fromCpuRegister(cpu: CpuRegister): RegisterOrPair {
+            return when(cpu) {
+                CpuRegister.A -> A
+                CpuRegister.X -> X
+                CpuRegister.Y -> Y
+            }
+        }
+    }
+
+    fun asCpuRegister(): CpuRegister = when(this) {
+        A -> CpuRegister.A
+        X -> CpuRegister.X
+        Y -> CpuRegister.Y
+        else -> throw IllegalArgumentException("no cpu hardware register for $this")
+    }
+
+    fun asScopedNameVirtualReg(type: DataType?): List<String> {
+        require(this in Cx16VirtualRegisters)
+        val suffix = when(type?.base) {
+            BaseDataType.UBYTE, BaseDataType.BOOL -> "L"
+            BaseDataType.BYTE -> "sL"
+            BaseDataType.WORD -> "s"
+            BaseDataType.UWORD, null -> ""
+            else -> throw kotlin.IllegalArgumentException("invalid register param type")
+        }
+        return listOf("cx16", name.lowercase()+suffix)
+    }
+}       // only used in parameter and return value specs in asm subroutines
+
+enum class Statusflag {
+    Pc,
+    Pz,     // don't use
+    Pv,
+    Pn;     // don't use
+
+    companion object {
+        val names by lazy { entries.map { it.toString()} }
+    }
+}
+
+enum class BranchCondition {
+    CS,
+    CC,
+    EQ,     // EQ == Z
+    Z,
+    NE,     // NE == NZ
+    NZ,
+    MI,     // MI == NEG
+    NEG,
+    PL,     // PL == POS
+    POS,
+    VS,
+    VC
+}
+
+val Cx16VirtualRegisters = arrayOf(
+    RegisterOrPair.R0, RegisterOrPair.R1, RegisterOrPair.R2, RegisterOrPair.R3,
+    RegisterOrPair.R4, RegisterOrPair.R5, RegisterOrPair.R6, RegisterOrPair.R7,
+    RegisterOrPair.R8, RegisterOrPair.R9, RegisterOrPair.R10, RegisterOrPair.R11,
+    RegisterOrPair.R12, RegisterOrPair.R13, RegisterOrPair.R14, RegisterOrPair.R15
+)
+
+val CpuRegisters = arrayOf(
+    RegisterOrPair.A, RegisterOrPair.X, RegisterOrPair.Y,
+    RegisterOrPair.AX, RegisterOrPair.AY, RegisterOrPair.XY
+)
+
+
+enum class OutputType {
+    RAW,
+    PRG,
+    XEX,
+    LIBRARY
+}
+
+enum class CbmPrgLauncherType {
+    BASIC,
+    NONE
+}
+
+enum class ZeropageType {
+    BASICSAFE,
+    FLOATSAFE,
+    KERNALSAFE,
+    FULL,
+    DONTUSE
+}
+
+enum class ZeropageWish {
+    REQUIRE_ZEROPAGE,
+    PREFER_ZEROPAGE,
+    DONTCARE,
+    NOT_IN_ZEROPAGE
+}
+
+enum class SplitWish {
+    DONTCARE,
+    SPLIT,
+    NOSPLIT
+}

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

@@ -0,0 +1,7 @@
+package prog8.code.core
+
+class InternalCompilerException(message: String?) : Exception(message)
+
+class AssemblyError(msg: String) : RuntimeException(msg)
+
+class ErrorsReportedException(message: String?) : Exception(message)

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

@@ -0,0 +1,44 @@
+package prog8.code.core
+
+import java.nio.file.Path
+
+enum class CpuType {
+    CPU6502,
+    CPU65C02,
+    VIRTUAL
+}
+
+interface ICompilationTarget: IStringEncoding, IMemSizer {
+    val name: String
+
+    val FLOAT_MAX_NEGATIVE: Double
+    val FLOAT_MAX_POSITIVE: Double
+    val FLOAT_MEM_SIZE: Int
+    val STARTUP_CODE_RESERVED_SIZE: UInt        // this is here, so that certain compiler targets are able to tune this
+    val PROGRAM_LOAD_ADDRESS : UInt
+    val PROGRAM_MEMTOP_ADDRESS: UInt
+    val BSSHIGHRAM_START: UInt
+    val BSSHIGHRAM_END: UInt
+    val BSSGOLDENRAM_START: UInt
+    val BSSGOLDENRAM_END: UInt
+
+    val cpu: CpuType
+    var zeropage: Zeropage
+    var golden: GoldenRam
+    val libraryPath: Path?
+    val customLauncher: List<String>
+    val additionalAssemblerOptions: String?
+    val defaultOutputType: OutputType
+
+    fun initializeMemoryAreas(compilerOptions: CompilationOptions)
+    fun getFloatAsmBytes(num: Number): String
+
+    fun convertFloatToBytes(num: Double): List<UByte>
+    fun convertBytesToFloat(bytes: List<UByte>): Double
+
+    fun launchEmulator(selectedEmulator: Int, programNameWithPath: Path, quiet: Boolean)
+    fun isIOAddress(address: UInt): Boolean
+
+    override fun encodeString(str: String, encoding: Encoding): List<UByte>
+    override fun decodeString(bytes: Iterable<UByte>, encoding: Encoding): String
+}

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

@@ -0,0 +1,18 @@
+package prog8.code.core
+
+interface IErrorReporter {
+    fun err(msg: String, position: Position)
+    fun warn(msg: String, position: Position)
+    fun info(msg: String, position: Position)
+    fun undefined(symbol: List<String>, position: Position)
+    fun noErrors(): Boolean
+    fun report()
+    fun finalizeNumErrors(numErrors: Int, numWarnings: Int, numInfos: Int) {
+        if(numErrors>0)
+            throw ErrorsReportedException("There are $numErrors errors, $numWarnings warnings, and $numInfos infos.")
+    }
+
+    fun noErrorForLine(position: Position): Boolean
+
+    fun printSingleError(errormessage: String)
+}

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

@@ -0,0 +1,15 @@
+package prog8.code.core
+
+interface IMemSizer {
+    fun memorySize(dt: DataType, numElements: Int?): Int
+
+    fun memorySize(dt: BaseDataType): Int {
+        if(dt.isPassByRef)
+            return memorySize(DataType.UWORD, null)      // a pointer size
+        try {
+            return memorySize(DataType.forDt(dt), null)
+        } catch (x: NoSuchElementException) {
+            throw IllegalArgumentException(x.message)
+        }
+    }
+}

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

@@ -0,0 +1,21 @@
+package prog8.code.core
+
+enum class Encoding(val prefix: String) {
+    DEFAULT("default"),         // depends on compilation target
+    PETSCII("petscii"),         // c64/c128/cx16
+    SCREENCODES("sc"),          // c64/c128/cx16
+    ATASCII("atascii"),         // atari
+    ISO("iso"),                 // cx16  (iso-8859-15)
+    ISO5("iso5"),               // cx16  (iso-8859-5, cyrillic)
+    ISO16("iso16"),             // cx16  (iso-8859-16, eastern european)
+    CP437("cp437"),             // cx16  (ibm pc, codepage 437)
+    KATAKANA("kata"),           // cx16  (katakana)
+    C64OS("c64os")              // c64 (C64 OS)
+}
+
+interface IStringEncoding {
+    val defaultEncoding: Encoding
+
+    fun encodeString(str: String, encoding: Encoding): List<UByte>
+    fun decodeString(bytes: Iterable<UByte>, encoding: Encoding): String
+}

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

@@ -0,0 +1,170 @@
+package prog8.code.core
+
+import com.github.michaelbull.result.Err
+import com.github.michaelbull.result.Ok
+import com.github.michaelbull.result.Result
+
+
+class MemAllocationError(message: String) : Exception(message)
+
+
+abstract class MemoryAllocator(protected val options: CompilationOptions) {
+    data class VarAllocation(val address: UInt, val dt: DataType, val size: Int)
+
+    abstract fun allocate(name: String,
+                          datatype: DataType,
+                          numElements: Int?,
+                          position: Position?,
+                          errors: IErrorReporter): Result<VarAllocation, MemAllocationError>
+}
+
+
+abstract class Zeropage(options: CompilationOptions): MemoryAllocator(options) {
+
+    abstract val SCRATCH_B1 : UInt      // temp storage for a single byte
+    abstract val SCRATCH_REG : UInt     // temp storage for a register byte, must be B1+1
+    abstract val SCRATCH_W1 : UInt      // temp storage 1 for a word  $fb+$fc
+    abstract val SCRATCH_W2 : UInt      // temp storage 2 for a word  $fb+$fc
+
+
+    // the variables allocated into Zeropage.
+    // name (scoped) ==> pair of address to (Datatype + bytesize)
+    val allocatedVariables = mutableMapOf<String, VarAllocation>()
+
+    val free = mutableListOf<UInt>()     // subclasses must set this to the appropriate free locations.
+
+    fun removeReservedFromFreePool() {
+        synchronized(this) {
+            for (reserved in options.zpReserved)
+                reserve(reserved)
+
+            free.removeAll(arrayOf(SCRATCH_B1, SCRATCH_REG, SCRATCH_W1, SCRATCH_W1 + 1u, SCRATCH_W2, SCRATCH_W2 + 1u))
+        }
+    }
+
+    fun retainAllowed() {
+        synchronized(this) {
+            for(allowed in options.zpAllowed)
+                free.retainAll { it in allowed }
+        }
+    }
+
+    fun availableBytes() = if(options.zeropage== ZeropageType.DONTUSE) 0 else free.size
+    fun hasByteAvailable() = if(options.zeropage== ZeropageType.DONTUSE) false else free.isNotEmpty()
+    fun hasWordAvailable(): Boolean {
+        if(options.zeropage== ZeropageType.DONTUSE)
+            return false
+
+        return free.windowed(2).any { it[0] == it[1] - 1u }
+    }
+
+    override fun allocate(name: String,
+                          datatype: DataType,
+                          numElements: Int?,
+                          position: Position?,
+                          errors: IErrorReporter): Result<VarAllocation, MemAllocationError> {
+
+        require(name.isEmpty() || name !in allocatedVariables) {"name can't be allocated twice"}
+
+        if(options.zeropage== ZeropageType.DONTUSE)
+            return Err(MemAllocationError("zero page usage has been disabled"))
+
+        val size: Int =
+                when {
+                    datatype.isIntegerOrBool -> options.compTarget.memorySize(datatype, null)
+                    datatype.isString || datatype.isArray -> {
+                        val memsize = options.compTarget.memorySize(datatype, numElements!!)
+                        if(position!=null)
+                            errors.warn("allocating a large value in zeropage; str/array $memsize bytes", position)
+                        else
+                            errors.warn("$name: allocating a large value in zeropage; str/array $memsize bytes", Position.DUMMY)
+                        memsize
+                    }
+                    datatype.isFloat -> {
+                        if (options.floats) {
+                            val memsize = options.compTarget.memorySize(DataType.FLOAT, null)
+                            if(position!=null)
+                                errors.warn("allocating a large value in zeropage; float $memsize bytes", position)
+                            else
+                                errors.warn("$name: allocating a large value in zeropage; float $memsize bytes", Position.DUMMY)
+                            memsize
+                        } else return Err(MemAllocationError("floating point option not enabled"))
+                    }
+                    else -> throw MemAllocationError("weird dt")
+                }
+
+        synchronized(this) {
+            if(free.isNotEmpty()) {
+                if(size==1) {
+                    for(candidate in free.minOrNull()!! .. free.maxOrNull()!!+1u) {
+                        if(oneSeparateByteFree(candidate))
+                            return Ok(VarAllocation(makeAllocation(candidate, 1, datatype, name), datatype,1))
+                    }
+                    return Ok(VarAllocation(makeAllocation(free[0], 1, datatype, name), datatype,1))
+                }
+                for(candidate in free.minOrNull()!! .. free.maxOrNull()!!+1u) {
+                    if (sequentialFree(candidate, size))
+                        return Ok(VarAllocation(makeAllocation(candidate, size, datatype, name), datatype, size))
+                }
+            }
+        }
+
+        return Err(MemAllocationError("no more free space in ZP to allocate $size sequential bytes"))
+    }
+
+    private fun reserve(range: UIntRange) = free.removeAll(range)
+
+    private fun makeAllocation(address: UInt, size: Int, datatype: DataType, name: String): UInt {
+        require(size>=0)
+        free.removeAll(address until address+size.toUInt())
+        if(name.isNotEmpty()) {
+            allocatedVariables[name] = when {
+                datatype.isNumericOrBool -> VarAllocation(address, datatype, size)        // numerical variables in zeropage never have an initial value here because they are set in separate initializer assignments
+                datatype.isString -> VarAllocation(address, datatype, size)
+                datatype.isArray -> VarAllocation(address, datatype, size)
+                else -> throw AssemblyError("invalid dt")
+            }
+        }
+        return address
+    }
+
+    private fun oneSeparateByteFree(address: UInt) = address in free && address-1u !in free && address+1u !in free
+    private fun sequentialFree(address: UInt, size: Int): Boolean {
+        require(size>0)
+        return free.containsAll((address until address+size.toUInt()).toList())
+    }
+}
+
+
+// TODO: this class is not yet used
+class GoldenRam(options: CompilationOptions, val region: UIntRange): MemoryAllocator(options) {
+    private var nextLocation: UInt = region.first
+
+    override fun allocate(
+        name: String,
+        datatype: DataType,
+        numElements: Int?,
+        position: Position?,
+        errors: IErrorReporter): Result<VarAllocation, MemAllocationError> {
+
+        val size: Int =
+            when {
+                datatype.isIntegerOrBool -> options.compTarget.memorySize(datatype, null)
+                datatype.isString -> numElements!!
+                datatype.isArray -> options.compTarget.memorySize(datatype, numElements!!)
+                datatype.isFloat -> {
+                    if (options.floats) {
+                        options.compTarget.memorySize(DataType.FLOAT, null)
+                    } else return Err(MemAllocationError("floating point option not enabled"))
+                }
+                else -> throw MemAllocationError("weird dt")
+            }
+
+        return if(nextLocation<=region.last && (region.last + 1u - nextLocation) >= size.toUInt()) {
+            val result = Ok(VarAllocation(nextLocation, datatype, size))
+            nextLocation += size.toUInt()
+            result
+        } else
+            Err(MemAllocationError("no more free space in Golden RAM to allocate $size sequential bytes"))
+    }
+}

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

@@ -0,0 +1,18 @@
+package prog8.code.core
+
+val AssociativeOperators = arrayOf("+", "*", "&", "|", "^", "==", "!=", "xor")       // note: and,or are not associative because of Shortcircuit/McCarthy evaluation
+val ComparisonOperators = arrayOf("==", "!=", "<", ">", "<=", ">=")
+val LogicalOperators = arrayOf("and", "or", "xor", "not", "in")
+val BitwiseOperators = arrayOf("&", "|", "^", "~")
+val PrefixOperators = arrayOf("+", "-", "~", "not")
+
+fun invertedComparisonOperator(operator: String) =
+    when (operator) {
+        "==" -> "!="
+        "!=" -> "=="
+        "<" -> ">="
+        ">" -> "<="
+        "<=" -> ">"
+        ">=" -> "<"
+        else -> null
+    }

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

@@ -0,0 +1,27 @@
+package prog8.code.core
+
+import prog8.code.sanitize
+import prog8.code.source.SourceCode
+import java.nio.file.InvalidPathException
+import kotlin.io.path.Path
+
+data class Position(val file: String, val line: Int, val startCol: Int, val endCol: Int) {
+    override fun toString(): String = "[$file: line $line col ${startCol+1}-${endCol+1}]"
+    fun toClickableStr(): String {
+        if(this===DUMMY)
+            return ""
+        if(SourceCode.isLibraryResource(file))
+            return "$file:$line:$startCol:"
+        return try {
+            val path = Path(file).sanitize().toString()
+            "file://$path:$line:$startCol:"
+        } catch(_: InvalidPathException) {
+            // this can occur on Windows when the source origin contains "invalid" characters such as ':'
+            "file://$file:$line:$startCol:"
+        }
+    }
+
+    companion object {
+        val DUMMY = Position("~dummy~", 0, 0, 0)
+    }
+}

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

@@ -0,0 +1,3 @@
+package prog8.code.core
+
+data class RegisterOrStatusflag(val registerOrPair: RegisterOrPair?, val statusflag: Statusflag?)

codeCore/src/prog8/code/source/ImportFileSystem.kt

@@ -0,0 +1,74 @@
+package prog8.code.source
+
+import prog8.code.core.Position
+import prog8.code.sanitize
+import java.nio.file.Path
+import java.util.*
+import kotlin.io.path.Path
+
+
+// Resource caching "filesystem".
+// Note that it leaves the decision to load a resource or an actual disk file to the caller.
+
+object ImportFileSystem {
+
+    fun expandTilde(path: String): String = if (path.startsWith("~")) {
+        val userHome = System.getProperty("user.home")
+        userHome + path.drop(1)
+    } else {
+        path
+    }
+
+    fun expandTilde(path: Path): Path = Path(expandTilde(path.toString()))
+
+    fun getFile(path: Path, isLibrary: Boolean=false): SourceCode {
+        val normalized = path.sanitize()
+        val cached = cache[normalized.toString()]
+        if (cached != null)
+            return cached
+        val file = SourceCode.File(normalized, isLibrary)
+        cache[normalized.toString()] = file
+        return file
+    }
+
+    fun getResource(name: String): SourceCode {
+        val cached = cache[name]
+        if (cached != null) return cached
+        val resource = SourceCode.Resource(name)
+        cache[name] = resource
+        return resource
+    }
+
+    fun retrieveSourceLine(position: Position): String {
+        if(SourceCode.isLibraryResource(position.file)) {
+            val cached = cache[SourceCode.withoutPrefix(position.file)]
+            if(cached != null)
+                return getLine(cached, position.line)
+        }
+        val cached = cache[position.file]
+        if(cached != null)
+            return getLine(cached, position.line)
+        val path = Path(position.file).sanitize()
+        val cached2 = cache[path.toString()]
+        if(cached2 != null)
+            return getLine(cached2, position.line)
+        throw NoSuchElementException("cannot get source line $position, with path $path")
+    }
+
+    private fun getLine(code: SourceCode, lineIndex: Int): String {
+        var spans = lineSpanCache[code]
+        if(spans==null) {
+            val lineSpans = Regex("^", RegexOption.MULTILINE).findAll(code.text).map { it.range.first }
+            val ends = lineSpans.drop(1) + code.text.length
+            spans = lineSpans.zip(ends).map { (start, end) -> LineSpan(start, end) }.toList().toTypedArray()
+            lineSpanCache[code] = spans
+        }
+        val span = spans[lineIndex - 1]
+        return code.text.substring(span.start, span.end).trim()
+    }
+
+    private class LineSpan(val start: Int, val end: Int)
+
+    private val cache = TreeMap<String, SourceCode>(String.CASE_INSENSITIVE_ORDER)
+    private val lineSpanCache = mutableMapOf<SourceCode, Array<LineSpan>>()
+}

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

@@ -0,0 +1,161 @@
+package prog8.code.source
+
+import prog8.code.sanitize
+import java.io.IOException
+import java.nio.file.Path
+import java.text.Normalizer
+import kotlin.io.path.Path
+import kotlin.io.path.absolute
+import kotlin.io.path.readText
+
+/**
+ * Encapsulates - and ties together - actual source code (=text) and its [origin].
+ */
+sealed class SourceCode {
+
+    /**
+     * Whether this [SourceCode] instance was created as a [Resource]
+     */
+    abstract val isFromResources: Boolean
+
+    /**
+     * Whether this [SourceCode] instance was created as a [File]
+     */
+    abstract val isFromFilesystem: Boolean
+
+    /**
+     * Whether this [SourceCode] instance was created from a library module file
+     */
+    abstract val isFromLibrary: Boolean
+
+    /**
+     * The logical name of the source code unit. Usually the module's name.
+     */
+    abstract val name: String
+
+    /**
+     * Where this [SourceCode] instance came from.
+     * This can be one of the following:
+     * * a normal string representation of a [java.nio.file.Path], if it originates from a file (see [File])
+     * * `string:44c56085` if was created via [String]
+     * * `library:/x/y/z.ext` if it is a library file that was loaded from resources (see [Resource])
+     */
+    abstract val origin: String
+
+    /**
+     * The source code as plain string.
+     */
+    abstract val text: String
+
+    /**
+     * Printable representation, deliberately does NOT return the actual text.
+     */
+    final override fun toString() = "${this.javaClass.name}[${this.origin}]"
+
+    companion object {
+
+        /**
+         * filename prefix to designate library files that will be retreived from internal resources rather than disk
+         */
+        private const val LIBRARYFILEPREFIX = "library:"
+        private const val STRINGSOURCEPREFIX = "string:"
+        val curdir: Path = Path(".").absolute()
+        fun relative(path: Path): Path = curdir.relativize(path.sanitize())
+        fun isRegularFilesystemPath(pathString: String) = !isLibraryResource(pathString) && !isStringResource(pathString)
+        fun isLibraryResource(path: String) = path.startsWith(LIBRARYFILEPREFIX)
+        fun isStringResource(path: String) = path.startsWith(STRINGSOURCEPREFIX)
+        fun withoutPrefix(path: String): String {
+            return if(isLibraryResource(path))
+                path.removePrefix(LIBRARYFILEPREFIX)
+            else if(isStringResource(path))
+                path.removePrefix(STRINGSOURCEPREFIX)
+            else
+                path
+        }
+    }
+
+    /**
+     * Turn a plain String into a [SourceCode] object.
+     * [origin] will be something like `string:44c56085`.
+     */
+    class Text(origText: String): SourceCode() {
+        override val text = origText.replace("\\R".toRegex(), "\n")      // normalize line endings
+        override val isFromResources = false
+        override val isFromFilesystem = false
+        override val isFromLibrary = false
+        override val origin = "$STRINGSOURCEPREFIX${System.identityHashCode(text).toString(16)}"
+        override val name = "<unnamed-text>"
+    }
+
+    /**
+     * Get [SourceCode] from the file represented by the specified Path.
+     * This immediately reads the file fully into memory.
+     * You can only get an instance of this via the ImportFileSystem object.
+     *
+     * [origin] will be the given path in absolute and normalized form.
+     * @throws NoSuchFileException if the file does not exist
+     * @throws FileSystemException if the file cannot be read
+     */
+    internal class File(path: Path, override val isFromLibrary: Boolean): SourceCode() {
+        override val text: String
+        override val origin: String
+        override val name: String
+        override val isFromResources = false
+        override val isFromFilesystem = true
+
+        init {
+            val normalized = path.normalize()
+            origin = relative(normalized).toString()
+            try {
+                val contents = Normalizer.normalize(normalized.readText(), Normalizer.Form.NFC)
+                text = contents.replace("\\R".toRegex(), "\n")      // normalize line endings
+                name = normalized.toFile().nameWithoutExtension
+            } catch (nfx: java.nio.file.NoSuchFileException) {
+                throw NoSuchFileException(normalized.toFile()).also { it.initCause(nfx) }
+            } catch (iox: IOException) {
+                throw FileSystemException(normalized.toFile()).also { it.initCause(iox) }
+            }
+        }
+    }
+
+    /**
+     * [origin]: `library:/x/y/z.p8` for a given `pathString` of "x/y/z.p8"
+     * You can only get an instance of this via the ImportFileSystem object.
+     */
+    internal class Resource(pathString: String): SourceCode() {
+        private val normalized = "/" + Path(pathString).normalize().toMutableList().joinToString("/")
+
+        override val isFromResources = true
+        override val isFromFilesystem = false
+        override val isFromLibrary = true
+        override val origin = "$LIBRARYFILEPREFIX$normalized"
+        override val text: String
+        override val name: String
+
+        init {
+            val rscURL = object {}.javaClass.getResource(normalized)
+            if (rscURL == null) {
+                val rscRoot = object {}.javaClass.getResource("/")
+                throw NoSuchFileException(
+                    java.io.File(normalized),
+                    reason = "looked in resources rooted at $rscRoot"
+                )
+            }
+            val stream = object {}.javaClass.getResourceAsStream(normalized)
+            val contents = stream!!.reader().use { Normalizer.normalize(it.readText(), Normalizer.Form.NFC) }
+            text = contents.replace("\\R".toRegex(), "\n")      // normalize line endings
+            name = Path(pathString).toFile().nameWithoutExtension
+        }
+    }
+
+    /**
+     * SourceCode for internally generated nodes (usually Modules)
+     */
+    class Generated(override val name: String) : SourceCode() {
+        override val isFromResources: Boolean = false
+        override val isFromFilesystem: Boolean = false
+        override val isFromLibrary: Boolean = false
+        override val origin: String = name
+        override val text: String = "<generated code node, no text representation>"
+    }
+}

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

@@ -0,0 +1,81 @@
+package prog8.code.target
+
+import prog8.code.core.*
+import prog8.code.target.encodings.Encoder
+import prog8.code.target.zp.C128Zeropage
+import java.nio.file.Path
+
+
+class C128Target: ICompilationTarget,
+    IStringEncoding by Encoder(true),
+    IMemSizer by NormalMemSizer(Mflpt5.FLOAT_MEM_SIZE) {
+
+    override val name = NAME
+    override val defaultEncoding = Encoding.PETSCII
+    override val libraryPath = null
+    override val customLauncher: List<String> = emptyList()
+    override val additionalAssemblerOptions = null
+    override val defaultOutputType = OutputType.PRG
+
+    companion object {
+        const val NAME = "c128"
+    }
+
+
+    override val cpu = CpuType.CPU6502
+
+    override val FLOAT_MAX_POSITIVE = Mflpt5.FLOAT_MAX_POSITIVE
+    override val FLOAT_MAX_NEGATIVE = Mflpt5.FLOAT_MAX_NEGATIVE
+    override val FLOAT_MEM_SIZE = Mflpt5.FLOAT_MEM_SIZE
+    override val STARTUP_CODE_RESERVED_SIZE = 20u
+    override val PROGRAM_LOAD_ADDRESS = 0x1c01u
+    override val PROGRAM_MEMTOP_ADDRESS = 0xc000u
+
+    override val BSSHIGHRAM_START = 0u    // TODO
+    override val BSSHIGHRAM_END = 0u      // TODO
+    override val BSSGOLDENRAM_START = 0u  // TODO
+    override val BSSGOLDENRAM_END = 0u    // TODO
+
+    override lateinit var zeropage: Zeropage
+    override lateinit var golden: GoldenRam
+
+    override fun getFloatAsmBytes(num: Number) = Mflpt5.fromNumber(num).makeFloatFillAsm()
+
+    override fun convertFloatToBytes(num: Double): List<UByte> {
+        val m5 = Mflpt5.fromNumber(num)
+        return listOf(m5.b0, m5.b1, m5.b2, m5.b3, m5.b4)
+    }
+
+    override fun convertBytesToFloat(bytes: List<UByte>): Double {
+        require(bytes.size==5) { "need 5 bytes" }
+        val m5 = Mflpt5(bytes[0], bytes[1], bytes[2], bytes[3], bytes[4])
+        return m5.toDouble()
+    }
+
+    override fun launchEmulator(selectedEmulator: Int, programNameWithPath: Path, quiet: Boolean) {
+        if(selectedEmulator!=1) {
+            System.err.println("The c128 target only supports the main emulator (Vice).")
+            return
+        }
+
+        if(!quiet)
+            println("\nStarting C-128 emulator x128...")
+
+        val viceMonlist = C64Target.viceMonListName(programNameWithPath.toString())
+        val cmdline = listOf("x128", "-silent", "-moncommands", viceMonlist,
+            "-autostartprgmode", "1", "-autostart-warp", "-autostart", "${programNameWithPath}.prg")
+        val processb = ProcessBuilder(cmdline)
+        if(!quiet)
+            processb.inheritIO()
+        val process: Process = processb.start()
+        process.waitFor()
+    }
+
+    override fun isIOAddress(address: UInt): Boolean = address==0u || address==1u || address in 0xd000u..0xdfffu
+
+    override fun initializeMemoryAreas(compilerOptions: CompilationOptions) {
+        zeropage = C128Zeropage(compilerOptions)
+        golden = GoldenRam(compilerOptions, UIntRange.EMPTY)    // TODO does the c128 have some of this somewhere?
+    }
+
+}

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

@@ -0,0 +1,111 @@
+package prog8.code.target
+
+import prog8.code.core.*
+import prog8.code.target.encodings.Encoder
+import prog8.code.target.zp.C64Zeropage
+import java.io.IOException
+import java.nio.file.Path
+
+
+class C64Target: ICompilationTarget,
+    IStringEncoding by Encoder(true),
+    IMemSizer by NormalMemSizer(Mflpt5.Companion.FLOAT_MEM_SIZE) {
+
+    override val name = NAME
+    override val defaultEncoding = Encoding.PETSCII
+    override val libraryPath = null
+    override val customLauncher: List<String> = emptyList()
+    override val additionalAssemblerOptions = null
+    override val defaultOutputType = OutputType.PRG
+
+    companion object {
+        const val NAME = "c64"
+
+        fun viceMonListName(baseFilename: String) = "$baseFilename.vice-mon-list"
+    }
+
+
+    override val cpu = CpuType.CPU6502
+
+    override val FLOAT_MAX_POSITIVE = Mflpt5.FLOAT_MAX_POSITIVE
+    override val FLOAT_MAX_NEGATIVE = Mflpt5.FLOAT_MAX_NEGATIVE
+    override val FLOAT_MEM_SIZE = Mflpt5.FLOAT_MEM_SIZE
+    override val STARTUP_CODE_RESERVED_SIZE = 20u
+    override val PROGRAM_LOAD_ADDRESS = 0x0801u
+    override val PROGRAM_MEMTOP_ADDRESS = 0xcfe0u      // $a000  if floats are used
+    // note that at $cfe0-$cfff are the 16 'virtual registers' R0-R15
+
+    override val BSSHIGHRAM_START = 0xc000u
+    override val BSSHIGHRAM_END = 0xcfdfu
+    override val BSSGOLDENRAM_START = 0u        // no golden ram on C64
+    override val BSSGOLDENRAM_END = 0u
+
+    override lateinit var zeropage: Zeropage
+    override lateinit var golden: GoldenRam
+
+    override fun getFloatAsmBytes(num: Number) = Mflpt5.fromNumber(num).makeFloatFillAsm()
+
+    override fun convertFloatToBytes(num: Double): List<UByte> {
+        val m5 = Mflpt5.fromNumber(num)
+        return listOf(m5.b0, m5.b1, m5.b2, m5.b3, m5.b4)
+    }
+
+    override fun convertBytesToFloat(bytes: List<UByte>): Double {
+        require(bytes.size==5) { "need 5 bytes" }
+        val m5 = Mflpt5(bytes[0], bytes[1], bytes[2], bytes[3], bytes[4])
+        return m5.toDouble()
+    }
+
+    override fun launchEmulator(selectedEmulator: Int, programNameWithPath: Path, quiet: Boolean) {
+        if(selectedEmulator!=1) {
+            System.err.println("The c64 target only supports the main emulator (Vice).")
+            return
+        }
+
+        for(emulator in listOf("x64sc", "x64")) {
+            if(!quiet)
+                println("\nStarting C-64 emulator $emulator...")
+
+            val viceMonlist = viceMonListName(programNameWithPath.toString())
+            val cmdline = listOf(emulator, "-silent", "-moncommands", viceMonlist,
+                "-autostartprgmode", "1", "-autostart-warp", "-autostart", "${programNameWithPath}.prg")
+            val processb = ProcessBuilder(cmdline)
+            if(!quiet)
+                processb.inheritIO()
+            val process: Process
+            try {
+                process=processb.start()
+            } catch(_: IOException) {
+                continue  // try the next emulator executable
+            }
+            process.waitFor()
+            break
+        }
+    }
+
+    override fun isIOAddress(address: UInt): Boolean = address==0u || address==1u || address in 0xd000u..0xdfffu
+
+    override fun initializeMemoryAreas(compilerOptions: CompilationOptions) {
+        zeropage = C64Zeropage(compilerOptions)
+        golden = GoldenRam(compilerOptions, UIntRange.EMPTY)
+    }
+
+}
+
+
+val CompilationTargets = listOf(
+    C64Target.NAME,
+    C128Target.NAME,
+    Cx16Target.NAME,
+    PETTarget.NAME,
+    VMTarget.NAME
+)
+
+fun getCompilationTargetByName(name: String) = when(name.lowercase()) {
+    C64Target.NAME -> C64Target()
+    C128Target.NAME -> C128Target()
+    Cx16Target.NAME -> Cx16Target()
+    PETTarget.NAME -> PETTarget()
+    VMTarget.NAME -> VMTarget()
+    else -> throw IllegalArgumentException("invalid compilation target")
+}

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

@@ -0,0 +1,173 @@
+package prog8.code.target
+
+import prog8.code.core.*
+import prog8.code.source.ImportFileSystem.expandTilde
+import prog8.code.target.encodings.Encoder
+import prog8.code.target.zp.ConfigurableZeropage
+import java.io.IOException
+import java.nio.file.Path
+import java.util.*
+import kotlin.io.path.Path
+import kotlin.io.path.inputStream
+import kotlin.io.path.isDirectory
+import kotlin.io.path.nameWithoutExtension
+
+
+class ConfigFileTarget(
+    override val name: String,
+    override val defaultEncoding: Encoding,
+    override val cpu: CpuType,
+    override val PROGRAM_LOAD_ADDRESS: UInt,
+    override val PROGRAM_MEMTOP_ADDRESS: UInt,
+    override val STARTUP_CODE_RESERVED_SIZE: UInt,
+    override val BSSHIGHRAM_START: UInt,
+    override val BSSHIGHRAM_END: UInt,
+    override val BSSGOLDENRAM_START: UInt,
+    override val BSSGOLDENRAM_END: UInt,
+    override val defaultOutputType: OutputType,
+    override val libraryPath: Path,
+    override val customLauncher: List<String>,
+    override val additionalAssemblerOptions: String?,
+    val ioAddresses: List<UIntRange>,
+    val zpScratchB1: UInt,
+    val zpScratchReg: UInt,
+    val zpScratchW1: UInt,
+    val zpScratchW2: UInt,
+    val virtualregistersStart: UInt,
+    val zpFullsafe: List<UIntRange>,
+    val zpKernalsafe: List<UIntRange>,
+    val zpBasicsafe: List<UIntRange>
+): ICompilationTarget, IStringEncoding by Encoder(true), IMemSizer by NormalMemSizer(8) {
+
+    companion object {
+
+        private fun Properties.getString(property: String): String {
+            val value = this.getProperty(property, null)
+            if(value!=null)
+                return value
+            throw NoSuchElementException("string property '$property' not found in config file")
+        }
+
+        private fun Properties.getInteger(property: String): UInt {
+            val value = this.getProperty(property, null)
+            if(value!=null) return parseInt(value)
+            throw NoSuchElementException("integer property '$property' not found in config file")
+        }
+
+        private fun parseInt(value: String): UInt {
+            if(value.startsWith("0x"))
+                return value.drop(2).toUInt(16)
+            if(value.startsWith("$"))
+                return value.drop(1).toUInt(16)
+            if(value.startsWith("%"))
+                return value.drop(1).toUInt(2)
+            return value.toUInt()
+        }
+
+        private fun parseAddressRanges(key: String, props: Properties): List<UIntRange> {
+            val rangesStr = props.getString(key)
+            if(rangesStr.isBlank())
+                return emptyList()
+            val result = mutableListOf<UIntRange>()
+            val ranges = rangesStr.split(",").map { it.trim() }
+            for(r in ranges) {
+                if ('-' in r) {
+                    val (fromStr, toStr) = r.split("-")
+                    val from = parseInt(fromStr.trim())
+                    val to = parseInt(toStr.trim())
+                    result.add(from..to)
+                } else {
+                    val address = parseInt(r)
+                    result.add(address..address)
+                }
+            }
+            return result
+        }
+
+        fun fromConfigFile(configfile: Path): ConfigFileTarget {
+            val props = Properties()
+            props.load(configfile.inputStream())
+
+            val cpuString = props.getString("cpu").uppercase()
+            val cpuType = try {
+                CpuType.valueOf(cpuString)
+            } catch (_: IllegalArgumentException) {
+                CpuType.valueOf("CPU$cpuString")
+            }
+            val ioAddresses = parseAddressRanges("io_regions", props)
+            val zpFullsafe = parseAddressRanges("zp_fullsafe", props)
+            val zpKernalsafe = parseAddressRanges("zp_kernalsafe", props)
+            val zpBasicsafe = parseAddressRanges("zp_basicsafe", props)
+
+            val libraryPath = expandTilde(Path(props.getString("library")))
+            if(!libraryPath.isDirectory())
+                throw IOException("invalid library path: $libraryPath")
+
+            val customLauncherStr = props.getProperty("custom_launcher_code", null)
+            val customLauncher =
+                if(customLauncherStr?.isNotBlank()==true)
+                    (customLauncherStr+"\n").lines().map { it.trimEnd() }
+                else emptyList()
+            val assemblerOptionsStr = props.getProperty("assembler_options", "").trim()
+            val assemblerOptions = assemblerOptionsStr.ifBlank { null }
+
+            val outputTypeString = props.getProperty("output_type", "PRG")
+            val defaultOutputType = OutputType.valueOf(outputTypeString.uppercase())
+
+            return ConfigFileTarget(
+                configfile.nameWithoutExtension,
+                Encoding.entries.first { it.prefix==props.getString("encoding") },
+                cpuType,
+                props.getInteger("load_address"),
+                props.getInteger("memtop"),
+                0u,         // used only in a very specific error condition check in a certain scenario...
+                props.getInteger("bss_highram_start"),
+                props.getInteger("bss_highram_end"),
+                props.getInteger("bss_goldenram_start"),
+                props.getInteger("bss_goldenram_end"),
+                defaultOutputType,
+                libraryPath,
+                customLauncher,
+                assemblerOptions,
+                ioAddresses,
+                props.getInteger("zp_scratch_b1"),
+                props.getInteger("zp_scratch_reg"),
+                props.getInteger("zp_scratch_w1"),
+                props.getInteger("zp_scratch_w2"),
+                props.getInteger("virtual_registers"),
+                zpFullsafe,
+                zpKernalsafe,
+                zpBasicsafe,
+            )
+        }
+    }
+
+    // TODO floats are not yet supported here, just enter some values
+    override val FLOAT_MAX_POSITIVE = 9.999999999e97
+    override val FLOAT_MAX_NEGATIVE = -9.999999999e97
+    override val FLOAT_MEM_SIZE = 8
+
+    override lateinit var zeropage: Zeropage
+    override lateinit var golden: GoldenRam     // TODO this is not yet used
+
+    override fun getFloatAsmBytes(num: Number) = TODO("floats")
+    override fun convertFloatToBytes(num: Double): List<UByte> = TODO("floats")
+    override fun convertBytesToFloat(bytes: List<UByte>): Double = TODO("floats")
+    override fun launchEmulator(selectedEmulator: Int, programNameWithPath: Path, quiet: Boolean) {
+        throw IllegalArgumentException("Custom compiler target cannot automatically launch an emulator. Do this manually.")
+    }
+
+    override fun isIOAddress(address: UInt): Boolean = ioAddresses.any { address in it }
+
+    override fun initializeMemoryAreas(compilerOptions: CompilationOptions) {
+        zeropage = ConfigurableZeropage(
+            zpScratchB1, zpScratchReg, zpScratchW1, zpScratchW2,
+            virtualregistersStart,
+            zpBasicsafe,
+            zpKernalsafe,
+            zpFullsafe,
+            compilerOptions
+        )
+        // note: there's no golden ram yet
+    }
+}

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

@@ -0,0 +1,94 @@
+package prog8.code.target
+
+import prog8.code.core.*
+import prog8.code.target.encodings.Encoder
+import prog8.code.target.zp.CX16Zeropage
+import java.nio.file.Path
+
+
+class Cx16Target: ICompilationTarget,
+    IStringEncoding by Encoder(true),
+    IMemSizer by NormalMemSizer(Mflpt5.Companion.FLOAT_MEM_SIZE) {
+
+    override val name = NAME
+    override val defaultEncoding = Encoding.PETSCII
+    override val libraryPath = null
+    override val customLauncher: List<String> = emptyList()
+    override val additionalAssemblerOptions = null
+    override val defaultOutputType = OutputType.PRG
+
+    companion object {
+        const val NAME = "cx16"
+    }
+
+
+    override val cpu = CpuType.CPU65C02
+
+    override val FLOAT_MAX_POSITIVE = Mflpt5.FLOAT_MAX_POSITIVE
+    override val FLOAT_MAX_NEGATIVE = Mflpt5.FLOAT_MAX_NEGATIVE
+    override val FLOAT_MEM_SIZE = Mflpt5.FLOAT_MEM_SIZE
+    override val STARTUP_CODE_RESERVED_SIZE = 20u
+    override val PROGRAM_LOAD_ADDRESS = 0x0801u
+    override val PROGRAM_MEMTOP_ADDRESS = 0x9f00u
+
+    override val BSSHIGHRAM_START = 0xa000u     // hiram bank 1, 8Kb, assumed to be active
+    override val BSSHIGHRAM_END = 0xbfffu       // Rom starts at $c000
+    override val BSSGOLDENRAM_START = 0x0400u
+    override val BSSGOLDENRAM_END = 0x07ffu
+
+    override lateinit var zeropage: Zeropage
+    override lateinit var golden: GoldenRam
+
+    override fun getFloatAsmBytes(num: Number) = Mflpt5.fromNumber(num).makeFloatFillAsm()
+
+    override fun convertFloatToBytes(num: Double): List<UByte> {
+        val m5 = Mflpt5.fromNumber(num)
+        return listOf(m5.b0, m5.b1, m5.b2, m5.b3, m5.b4)
+    }
+
+    override fun convertBytesToFloat(bytes: List<UByte>): Double {
+        require(bytes.size==5) { "need 5 bytes" }
+        val m5 = Mflpt5(bytes[0], bytes[1], bytes[2], bytes[3], bytes[4])
+        return m5.toDouble()
+    }
+
+    override fun launchEmulator(selectedEmulator: Int, programNameWithPath: Path, quiet: Boolean) {
+        val emulator: String
+        val extraArgs: List<String>
+
+        when(selectedEmulator) {
+            1 -> {
+                emulator = "x16emu"
+                extraArgs = listOf("-debug")
+            }
+            2 -> {
+                emulator = "box16"
+                extraArgs = listOf("-sym", C64Target.viceMonListName(programNameWithPath.toString()))
+            }
+            else -> {
+                System.err.println("Cx16 target only supports x16emu and box16 emulators.")
+                return
+            }
+        }
+
+        if(!quiet)
+            println("\nStarting Commander X16 emulator $emulator...")
+
+        val cmdline = listOf(emulator, "-scale", "2", "-rtc", "-run", "-prg", "${programNameWithPath}.prg") + extraArgs
+        val processb = ProcessBuilder(cmdline)
+        if(!quiet)
+            processb.inheritIO()
+        processb.environment()["PULSE_LATENCY_MSEC"] = "10"
+        val process: Process = processb.start()
+        process.waitFor()
+    }
+
+    override fun isIOAddress(address: UInt): Boolean = address==0u || address==1u || address in 0x9f00u..0x9fffu
+
+    override fun initializeMemoryAreas(compilerOptions: CompilationOptions) {
+        zeropage = CX16Zeropage(compilerOptions)
+        golden = GoldenRam(compilerOptions, BSSGOLDENRAM_START..BSSGOLDENRAM_END)
+    }
+
+
+}

codeCore/src/prog8/code/target/Mflpt5.kt

@@ -1,12 +1,10 @@
-package prog8.codegen.target.cbm
+package prog8.code.target
 
-import prog8.compilerinterface.IMachineFloat
-import prog8.compilerinterface.InternalCompilerException
+import prog8.code.core.InternalCompilerException
 import kotlin.math.absoluteValue
 import kotlin.math.pow
 
-
-data class Mflpt5(val b0: UByte, val b1: UByte, val b2: UByte, val b3: UByte, val b4: UByte): IMachineFloat {
+data class Mflpt5(val b0: UByte, val b1: UByte, val b2: UByte, val b3: UByte, val b4: UByte) {
 
     companion object {
         const val FLOAT_MAX_POSITIVE = 1.7014118345e+38         // bytes: 255,127,255,255,255
@@ -58,7 +56,7 @@ data class Mflpt5(val b0: UByte, val b1: UByte, val b2: UByte, val b3: UByte, va
         }
     }
 
-    override fun toDouble(): Double {
+    fun toDouble(): Double {
         if (this == zero) return 0.0
         val exp = b0.toInt() - 128
         val sign = (b1.toInt() and 0x80) > 0
@@ -67,7 +65,7 @@ data class Mflpt5(val b0: UByte, val b1: UByte, val b2: UByte, val b3: UByte, va
         return if (sign) -result else result
     }
 
-    override fun makeFloatFillAsm(): String {
+    fun makeFloatFillAsm(): String {
         val b0 = "$" + b0.toString(16).padStart(2, '0')
         val b1 = "$" + b1.toString(16).padStart(2, '0')
         val b2 = "$" + b2.toString(16).padStart(2, '0')

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

@@ -0,0 +1,34 @@
+package prog8.code.target
+
+import prog8.code.core.BaseDataType
+import prog8.code.core.DataType
+import prog8.code.core.IMemSizer
+
+internal class NormalMemSizer(val floatsize: Int): IMemSizer {
+
+    override fun memorySize(dt: DataType, numElements: Int?): Int {
+        if(dt.isArray) {
+            if(numElements==null) return 2      // treat it as a pointer size
+            return when(dt.sub) {
+                BaseDataType.BOOL, BaseDataType.UBYTE, BaseDataType.BYTE -> numElements
+                BaseDataType.UWORD, BaseDataType.WORD, BaseDataType.STR -> numElements * 2
+                BaseDataType.FLOAT-> numElements * floatsize
+                BaseDataType.UNDEFINED -> throw IllegalArgumentException("undefined has no memory size")
+                else -> throw IllegalArgumentException("invalid sub type")
+            }
+        }
+        else if (dt.isString) {
+            return numElements        // treat it as the size of the given string with the length
+                ?: 2    // treat it as the size to store a string pointer
+        }
+
+        return when {
+            dt.isByteOrBool -> 1 * (numElements ?: 1)
+            dt.isFloat -> floatsize * (numElements ?: 1)
+            dt.isLong -> 4 * (numElements ?: 1)
+            dt.isUndefined -> throw IllegalArgumentException("undefined has no memory size")
+            else -> 2 * (numElements ?: 1)
+        }
+    }
+
+}

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

@@ -0,0 +1,80 @@
+package prog8.code.target
+
+import prog8.code.core.*
+import prog8.code.target.encodings.Encoder
+import prog8.code.target.zp.PETZeropage
+import java.nio.file.Path
+
+
+class PETTarget: ICompilationTarget,
+    IStringEncoding by Encoder(true),
+    IMemSizer by NormalMemSizer(Mflpt5.Companion.FLOAT_MEM_SIZE) {
+
+    override val name = NAME
+    override val defaultEncoding = Encoding.PETSCII
+    override val libraryPath = null
+    override val customLauncher: List<String> = emptyList()
+    override val additionalAssemblerOptions = null
+    override val defaultOutputType = OutputType.PRG
+
+    companion object {
+        const val NAME = "pet32"
+    }
+
+    override val cpu = CpuType.CPU6502
+
+    override val FLOAT_MAX_POSITIVE = Mflpt5.FLOAT_MAX_POSITIVE
+    override val FLOAT_MAX_NEGATIVE = Mflpt5.FLOAT_MAX_NEGATIVE
+    override val FLOAT_MEM_SIZE = Mflpt5.FLOAT_MEM_SIZE
+    override val STARTUP_CODE_RESERVED_SIZE = 20u
+    override val PROGRAM_LOAD_ADDRESS = 0x0401u
+    override val PROGRAM_MEMTOP_ADDRESS = 0x8000u
+
+    override val BSSHIGHRAM_START = 0u
+    override val BSSHIGHRAM_END = 0u
+    override val BSSGOLDENRAM_START = 0u
+    override val BSSGOLDENRAM_END = 0u
+
+    override lateinit var zeropage: Zeropage
+    override lateinit var golden: GoldenRam
+
+    override fun getFloatAsmBytes(num: Number) = Mflpt5.fromNumber(num).makeFloatFillAsm()
+
+    override fun convertFloatToBytes(num: Double): List<UByte> {
+        val m5 = Mflpt5.fromNumber(num)
+        return listOf(m5.b0, m5.b1, m5.b2, m5.b3, m5.b4)
+    }
+
+    override fun convertBytesToFloat(bytes: List<UByte>): Double {
+        require(bytes.size==5) { "need 5 bytes" }
+        val m5 = Mflpt5(bytes[0], bytes[1], bytes[2], bytes[3], bytes[4])
+        return m5.toDouble()
+    }
+
+    override fun launchEmulator(selectedEmulator: Int, programNameWithPath: Path, quiet: Boolean) {
+        if(selectedEmulator!=1) {
+            System.err.println("The pet target only supports the main emulator (Vice).")
+            return
+        }
+
+        if(!quiet)
+            println("\nStarting PET emulator...")
+
+        val viceMonlist = C64Target.viceMonListName(programNameWithPath.toString())
+        val cmdline = listOf("xpet", "-model", "4032", "-ramsize", "32", "-videosize", "40", "-silent", "-moncommands", viceMonlist,
+            "-autostartprgmode", "1", "-autostart-warp", "-autostart", "${programNameWithPath}.prg")
+        val processb = ProcessBuilder(cmdline)
+        if(!quiet)
+            processb.inheritIO()
+        val process=processb.start()
+        process.waitFor()
+    }
+
+    override fun isIOAddress(address: UInt): Boolean = address in 0xe800u..0xe8ffu
+
+    override fun initializeMemoryAreas(compilerOptions: CompilationOptions) {
+        zeropage = PETZeropage(compilerOptions)
+        golden = GoldenRam(compilerOptions, UIntRange.EMPTY)
+    }
+
+}

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

@@ -0,0 +1,111 @@
+package prog8.code.target
+
+import prog8.code.core.*
+import prog8.code.target.encodings.Encoder
+import java.nio.file.Path
+import kotlin.io.path.isReadable
+import kotlin.io.path.name
+import kotlin.io.path.readText
+
+class VMTarget: ICompilationTarget,
+    IStringEncoding by Encoder(false),
+    IMemSizer by NormalMemSizer(FLOAT_MEM_SIZE) {
+
+    override val name = NAME
+    override val defaultEncoding = Encoding.ISO
+    override val libraryPath = null
+    override val customLauncher: List<String> = emptyList()
+    override val additionalAssemblerOptions = null
+    override val defaultOutputType = OutputType.PRG
+
+    companion object {
+        const val NAME = "virtual"
+        const val FLOAT_MEM_SIZE = 8             // 64-bits double
+    }
+
+    override val cpu = CpuType.VIRTUAL
+
+    override val FLOAT_MAX_POSITIVE = Double.MAX_VALUE
+    override val FLOAT_MAX_NEGATIVE = -Double.MAX_VALUE
+    override val FLOAT_MEM_SIZE = VMTarget.FLOAT_MEM_SIZE
+    override val STARTUP_CODE_RESERVED_SIZE = 0u  // not actually used
+    override val PROGRAM_LOAD_ADDRESS = 0u      // not actually used
+    override val PROGRAM_MEMTOP_ADDRESS = 0xffffu  // not actually used
+
+    override val BSSHIGHRAM_START = 0u          // not actually used
+    override val BSSHIGHRAM_END = 0u            // not actually used
+    override val BSSGOLDENRAM_START = 0u        // not actually used
+    override val BSSGOLDENRAM_END = 0u          // not actually used
+    override lateinit var zeropage: Zeropage    // not actually used
+    override lateinit var golden: GoldenRam     // not actually used
+
+    override fun getFloatAsmBytes(num: Number): String {
+        // little endian binary representation
+        val bits = num.toDouble().toBits().toULong()
+        val hexStr = bits.toString(16).padStart(16, '0')
+        val parts = hexStr.chunked(2).map { "$$it" }
+        return parts.joinToString(", ")
+    }
+
+    override fun convertFloatToBytes(num: Double): List<UByte> {
+        val bits = num.toBits().toULong()
+        val hexStr = bits.toString(16).padStart(16, '0')
+        val parts = hexStr.chunked(2).map { it.toInt(16).toUByte() }
+        return parts
+    }
+
+    override fun convertBytesToFloat(bytes: List<UByte>): Double {
+        require(bytes.size==8) { "need 8 bytes" }
+        val b0 = bytes[0].toLong() shl (8*7)
+        val b1 = bytes[1].toLong() shl (8*6)
+        val b2 = bytes[2].toLong() shl (8*5)
+        val b3 = bytes[3].toLong() shl (8*4)
+        val b4 = bytes[4].toLong() shl (8*3)
+        val b5 = bytes[5].toLong() shl (8*2)
+        val b6 = bytes[6].toLong() shl (8*1)
+        val b7 = bytes[7].toLong() shl (8*0)
+        return Double.fromBits(b0 or b1 or b2 or b3 or b4 or b5 or b6 or b7)
+    }
+
+    override fun launchEmulator(selectedEmulator: Int, programNameWithPath: Path, quiet: Boolean) {
+        if(!quiet)
+            println("\nStarting Virtual Machine...")
+
+        // to not have external module dependencies in our own module, we launch the virtual machine via reflection
+        val vm = Class.forName("prog8.vm.VmRunner").getDeclaredConstructor().newInstance() as IVirtualMachineRunner
+        val filename = programNameWithPath.name
+        if(programNameWithPath.isReadable()) {
+            vm.runProgram(programNameWithPath.readText(), quiet)
+        } else {
+            val withExt = programNameWithPath.resolveSibling("$filename.p8ir")
+            if(withExt.isReadable())
+                vm.runProgram(withExt.readText(), quiet)
+            else
+                throw java.nio.file.NoSuchFileException(withExt.name, null, "not a .p8ir file")
+        }
+    }
+
+    override fun isIOAddress(address: UInt): Boolean = false
+
+    override fun initializeMemoryAreas(compilerOptions: CompilationOptions) {
+        zeropage = VirtualZeropage(compilerOptions)
+        golden = GoldenRam(compilerOptions, UIntRange.EMPTY)
+    }
+}
+
+
+
+interface IVirtualMachineRunner {
+    fun runProgram(irSource: String, quiet: Boolean)
+}
+
+private class VirtualZeropage(options: CompilationOptions): Zeropage(options) {
+    override val SCRATCH_B1: UInt
+        get() = throw IllegalStateException("virtual shouldn't use this zeropage variable")
+    override val SCRATCH_REG: UInt
+        get() = throw IllegalStateException("virtual shouldn't use this zeropage variable")
+    override val SCRATCH_W1: UInt
+        get() = throw IllegalStateException("virtual shouldn't use this zeropage variable")
+    override val SCRATCH_W2: UInt
+        get() = throw IllegalStateException("virtual shouldn't use this zeropage variable")
+}

codeCore/src/prog8/code/target/encodings/AtasciiEncoding.kt

@@ -0,0 +1,215 @@
+package prog8.code.target.encodings
+
+import com.github.michaelbull.result.Ok
+import com.github.michaelbull.result.Result
+import java.io.CharConversionException
+
+object AtasciiEncoding {
+
+    private val decodeTable: CharArray = charArrayOf(
+        // $00
+        '♥',
+        '├',
+        '\uf130',    //  🮇    0x02 -> RIGHT ONE QUARTER BLOCK (CUS)
+        '┘',
+        '┤',
+        '┐',
+        '╱',
+        '╲',
+        '◢',
+        '▗',
+        '◣',
+        '▝',
+        '▘',
+        '\uf132',    //  🮂    0x1d -> UPPER ONE QUARTER BLOCK (CUS)
+        '▂',
+        '▖',
+
+        // $10
+        '♣',
+        '┌',
+        '─',
+        '┼',
+        '•',
+        '▄',
+        '▎',
+        '┬',
+        '┴',
+        '▌',
+        '└',
+        '\u001b',           // $1b = escape
+        '\ufffe',           // UNDEFINED CHAR.   $1c = cursor up
+        '\ufffe',           // UNDEFINED CHAR.   $1d = cursor down
+        '\ufffe',           // UNDEFINED CHAR.   $1e = cursor left
+        '\ufffe',           // UNDEFINED CHAR.   $1f = cursor right
+
+        // $20
+        ' ',
+        '!',
+        '"',
+        '#',
+        '$',
+        '%',
+        '&',
+        '\'',
+        '(',
+        ')',
+        '*',
+        '+',
+        ',',
+        '-',
+        '.',
+        '/',
+
+        // $30
+        '0',
+        '1',
+        '2',
+        '3',
+        '4',
+        '5',
+        '6',
+        '7',
+        '8',
+        '9',
+        ':',
+        ';',
+        '<',
+        '=',
+        '>',
+        '?',
+
+        // $40
+        '@',
+        'A',
+        'B',
+        'C',
+        'D',
+        'E',
+        'F',
+        'G',
+        'H',
+        'I',
+        'J',
+        'K',
+        'L',
+        'M',
+        'N',
+        'O',
+
+        // $50
+        'P',
+        'Q',
+        'R',
+        'S',
+        'T',
+        'U',
+        'V',
+        'W',
+        'X',
+        'Y',
+        'Z',
+        '[',
+        '\\',
+        ']',
+        '^',
+        '_',
+
+        // $60
+        '♦',
+        'a',
+        'b',
+        'c',
+        'd',
+        'e',
+        'f',
+        'g',
+        'h',
+        'i',
+        'j',
+        'k',
+        'l',
+        'm',
+        'n',
+        'o',
+
+        // $70
+        'p',
+        'q',
+        'r',
+        's',
+        't',
+        'u',
+        'v',
+        'w',
+        'x',
+        'y',
+        'z',
+        '♠',
+        '|',
+        '\u000c',    //       $7d -> FORM FEED (CLEAR SCREEN)
+        '\u0008',    //       $7e -> BACKSPACE
+        '\u0009',    //       $7f -> TAB
+
+        // $80-$ff are reversed video characters + various special characters.
+        '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe',
+        '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe',
+        // $90
+        '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe',
+        '\ufffe',
+        '\ufffe',
+        '\ufffe',
+        '\n',               // $9b -> EOL/RETURN
+        '\ufffe',           // UNDEFINED   $9c = DELETE LINE
+        '\ufffe',           // UNDEFINED   $9d = INSERT LINE
+        '\ufffe',           // UNDEFINED   $9e = CLEAR TAB STOP
+        '\ufffe',           // UNDEFINED   $9f = SET TAB STOP
+        // $a0
+        '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe',
+        '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe',
+        // $b0
+        '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe',
+        '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe',
+        // $c0
+        '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe',
+        '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe',
+        // $d0
+        '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe',
+        '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe',
+        // $e0
+        '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe',
+        '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe',
+        // $f0
+        '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe',
+        '\ufffe',
+        '\ufffe',
+        '\ufffe',
+        '\ufffe',
+        '\ufffe',
+        '\u0007',           // $fd = bell/beep
+        '\u007f',           // $fe = DELETE
+        '\ufffe'            // UNDEFINED     $ff = INSERT
+    )
+
+    private val encodeTable = decodeTable.withIndex().associate{it.value to it.index}
+
+
+    fun encode(str: String): Result<List<UByte>, CharConversionException> {
+        val mapped = str.map { chr ->
+            when (chr) {
+                '\r' -> 0x9bu
+                '\u0000' -> 0u
+                in '\u8000'..'\u80ff' -> {
+                    // special case: take the lower 8 bit hex value directly
+                    (chr.code - 0x8000).toUByte()
+                }
+                else -> encodeTable.getValue(chr).toUByte()
+            }
+        }
+        return Ok(mapped)
+    }
+
+    fun decode(bytes: Iterable<UByte>): Result<String, CharConversionException> {
+        return Ok(bytes.map { decodeTable[it.toInt()] }.joinToString(""))
+    }
+}

codeCore/src/prog8/code/target/encodings/C64osEncoding.kt

@@ -0,0 +1,327 @@
+package prog8.code.target.encodings
+
+import com.github.michaelbull.result.Err
+import com.github.michaelbull.result.Ok
+import com.github.michaelbull.result.Result
+import java.io.CharConversionException
+
+object C64osEncoding {
+
+    // decoding:  from C64 OS Screencodes (0-255) to unicode
+    // character table from:
+    // https://www.c64os.com/c64os/usersguide/appendices#charactersets
+
+    private val decodingC64os = charArrayOf(
+        '@'     ,    //  @    0x00 -> COMMERCIAL AT
+        'a'     ,    //  a    0x01 -> LATIN SMALL LETTER A
+        'b'     ,    //  b    0x02 -> LATIN SMALL LETTER B
+        'c'     ,    //  c    0x03 -> LATIN SMALL LETTER C
+        'd'     ,    //  d    0x04 -> LATIN SMALL LETTER D
+        'e'     ,    //  e    0x05 -> LATIN SMALL LETTER E
+        'f'     ,    //  f    0x06 -> LATIN SMALL LETTER F
+        'g'     ,    //  g    0x07 -> LATIN SMALL LETTER G
+        'h'     ,    //  h    0x08 -> LATIN SMALL LETTER H
+        'i'     ,    //  i    0x09 -> LATIN SMALL LETTER I
+        'j'     ,    //  j    0x0A -> LATIN SMALL LETTER J
+        'k'     ,    //  k    0x0B -> LATIN SMALL LETTER K
+        'l'     ,    //  l    0x0C -> LATIN SMALL LETTER L
+        'm'     ,    //  m    0x0D -> LATIN SMALL LETTER M
+        'n'     ,    //  n    0x0E -> LATIN SMALL LETTER N
+        'o'     ,    //  o    0x0F -> LATIN SMALL LETTER O
+        'p'     ,    //  p    0x10 -> LATIN SMALL LETTER P
+        'q'     ,    //  q    0x11 -> LATIN SMALL LETTER Q
+        'r'     ,    //  r    0x12 -> LATIN SMALL LETTER R
+        's'     ,    //  s    0x13 -> LATIN SMALL LETTER S
+        't'     ,    //  t    0x14 -> LATIN SMALL LETTER T
+        'u'     ,    //  u    0x15 -> LATIN SMALL LETTER U
+        'v'     ,    //  v    0x16 -> LATIN SMALL LETTER V
+        'w'     ,    //  w    0x17 -> LATIN SMALL LETTER W
+        'x'     ,    //  x    0x18 -> LATIN SMALL LETTER X
+        'y'     ,    //  y    0x19 -> LATIN SMALL LETTER Y
+        'z'     ,    //  z    0x1A -> LATIN SMALL LETTER Z
+        '['     ,    //  [    0x1B -> LEFT SQUARE BRACKET
+        '\\'    ,    //  \    0x1C -> REVERSE SOLIDUS
+        ']'     ,    //  ]    0x1D -> RIGHT SQUARE BRACKET
+        '^'     ,    //  ^    0x1E -> CIRCUMFLEX
+        '_'     ,    //  _    0x1F -> UNDERSCORE
+        ' '     ,    //       0x20 -> SPACE
+        '!'     ,    //  !    0x21 -> EXCLAMATION MARK
+        '"'     ,    //  "    0x22 -> QUOTATION MARK
+        '#'     ,    //  #    0x23 -> NUMBER SIGN
+        '$'     ,    //  $    0x24 -> DOLLAR SIGN
+        '%'     ,    //  %    0x25 -> PERCENT SIGN
+        '&'     ,    //  &    0x26 -> AMPERSAND
+        '\''    ,    //  '    0x27 -> APOSTROPHE
+        '('     ,    //  (    0x28 -> LEFT PARENTHESIS
+        ')'     ,    //  )    0x29 -> RIGHT PARENTHESIS
+        '*'     ,    //  *    0x2A -> ASTERISK
+        '+'     ,    //  +    0x2B -> PLUS SIGN
+        ','     ,    //  ,    0x2C -> COMMA
+        '-'     ,    //  -    0x2D -> HYPHEN-MINUS
+        '.'     ,    //  .    0x2E -> FULL STOP
+        '/'     ,    //  /    0x2F -> SOLIDUS
+        '0'     ,    //  0    0x30 -> DIGIT ZERO
+        '1'     ,    //  1    0x31 -> DIGIT ONE
+        '2'     ,    //  2    0x32 -> DIGIT TWO
+        '3'     ,    //  3    0x33 -> DIGIT THREE
+        '4'     ,    //  4    0x34 -> DIGIT FOUR
+        '5'     ,    //  5    0x35 -> DIGIT FIVE
+        '6'     ,    //  6    0x36 -> DIGIT SIX
+        '7'     ,    //  7    0x37 -> DIGIT SEVEN
+        '8'     ,    //  8    0x38 -> DIGIT EIGHT
+        '9'     ,    //  9    0x39 -> DIGIT NINE
+        ':'     ,    //  :    0x3A -> COLON
+        ';'     ,    //  ;    0x3B -> SEMICOLON
+        '<'     ,    //  <    0x3C -> LESS-THAN SIGN
+        '='     ,    //  =    0x3D -> EQUALS SIGN
+        '>'     ,    //  >    0x3E -> GREATER-THAN SIGN
+        '?'     ,    //  ?    0x3F -> QUESTION MARK
+        '`'     ,    //  `    0x40 -> GRAVE ACCENT
+        'A'     ,    //  A    0x41 -> LATIN CAPITAL LETTER A
+        'B'     ,    //  B    0x42 -> LATIN CAPITAL LETTER B
+        'C'     ,    //  C    0x43 -> LATIN CAPITAL LETTER C
+        'D'     ,    //  D    0x44 -> LATIN CAPITAL LETTER D
+        'E'     ,    //  E    0x45 -> LATIN CAPITAL LETTER E
+        'F'     ,    //  F    0x46 -> LATIN CAPITAL LETTER F
+        'G'     ,    //  G    0x47 -> LATIN CAPITAL LETTER G
+        'H'     ,    //  H    0x48 -> LATIN CAPITAL LETTER H
+        'I'     ,    //  I    0x49 -> LATIN CAPITAL LETTER I
+        'J'     ,    //  J    0x4A -> LATIN CAPITAL LETTER J
+        'K'     ,    //  K    0x4B -> LATIN CAPITAL LETTER K
+        'L'     ,    //  L    0x4C -> LATIN CAPITAL LETTER L
+        'M'     ,    //  M    0x4D -> LATIN CAPITAL LETTER M
+        'N'     ,    //  N    0x4E -> LATIN CAPITAL LETTER N
+        'O'     ,    //  O    0x4F -> LATIN CAPITAL LETTER O
+        'P'     ,    //  P    0x50 -> LATIN CAPITAL LETTER P
+        'Q'     ,    //  Q    0x51 -> LATIN CAPITAL LETTER Q
+        'R'     ,    //  R    0x52 -> LATIN CAPITAL LETTER R
+        'S'     ,    //  S    0x53 -> LATIN CAPITAL LETTER S
+        'T'     ,    //  T    0x54 -> LATIN CAPITAL LETTER T
+        'U'     ,    //  U    0x55 -> LATIN CAPITAL LETTER U
+        'V'     ,    //  V    0x56 -> LATIN CAPITAL LETTER V
+        'W'     ,    //  W    0x57 -> LATIN CAPITAL LETTER W
+        'X'     ,    //  X    0x58 -> LATIN CAPITAL LETTER X
+        'Y'     ,    //  Y    0x59 -> LATIN CAPITAL LETTER Y
+        'Z'     ,    //  Z    0x5A -> LATIN CAPITAL LETTER Z
+        '{'     ,    //  {    0x5B -> LEFT BRACE
+        '|'     ,    //  |    0x5C -> VERTICAL BAR
+        '}'     ,    //  }    0x5D -> RIGHT BRACE
+        '~'     ,    //  ~    0x5E -> TILDE
+        '\ufffe',    //       0x5F -> RESERVED
+        '\u00a0',    //       0x60 -> NO-BREAK SPACE (TRANSPARENT)
+        '\ufffe',    //       0x61 -> COMMODORE SYMBOL
+        '\u2191',    //  ↑    0x62 -> UP ARROW
+        '\u2193',    //  ↓    0x63 -> DOWN ARROW
+        '\u2190',    //  ←    0x64 -> LEFT ARROW
+        '\u2192',    //  →    0x65 -> RIGHT ARROW
+        '\u231A',    //  ⌚   0x66 -> WATCH (ANALOG CLOCKFACE)
+        '\u21BB',    //  ↻    0x67 -> CYCLE ARROWS
+        '\u2026',    //  …    0x68 -> ELLIPSIS
+        '\u25a7',    //  ▧    0x69 -> DIAGNONAL STRIPES
+        '\u2610',    //  ☐    0x6A -> CHECKBOX UNCHECKED
+        '\u2611',    //  ☑    0x6B -> CHECKBOX CHECKED
+        '\ufffe',    //       0x6C -> RADIO BUTTON UNSELECTED
+        '\ufffe',    //       0x6D -> RADIO BUTTON SELECTED
+        '\ufffe',    //       0x6E -> UTILITY CLOSE BUTTON
+        '\ufffe',    //       0x6F -> UTILITY TITLE BAR
+        '\u00a9',    //  ©    0x70 -> COPYRIGHT
+        '\u2713',    //  ✓    0x71 -> CHECKMARK
+        '\u2261',    //  ≡    0x72 -> THREE HORIZONTAL STRIPES
+        '\ufffe',    //       0x73 -> TICK TRACK
+        '\ufffe',    //       0x74 -> TICK TRACK NUB
+        '\ufffe',    //       0x75 -> TAB CORNER
+        '\u2980',    //  ⦀    0x76 -> THREE VERTICAL STRIPES
+        '\ufffe',    //       0x77 -> CUSTOM 1
+        '\ufffe',    //       0x78 -> CUSTOM 2
+        '\ufffe',    //       0x79 -> CUSTOM 3
+        '\ufffe',    //       0x7A -> CUSTOM 4
+        '\ufffe',    //       0x7B -> CUSTOM 5
+        '\ufffe',    //       0x7C -> CUSTOM 6
+        '\ufffe',    //       0x7D -> CUSTOM 7
+        '\ufffe',    //       0x7E -> CUSTOM 8
+        '\ufffe',    //       0x7F -> CUSTOM 9
+        '\ufffe',    //       0x80 -> REVERSED COMMERCIAL AT
+        '\ufffe',    //       0x81 -> REVERSED LATIN SMALL LETTER A
+        '\ufffe',    //       0x82 -> REVERSED LATIN SMALL LETTER B
+        '\ufffe',    //       0x83 -> REVERSED LATIN SMALL LETTER C
+        '\ufffe',    //       0x84 -> REVERSED LATIN SMALL LETTER D
+        '\ufffe',    //       0x85 -> REVERSED LATIN SMALL LETTER E
+        '\ufffe',    //       0x86 -> REVERSED LATIN SMALL LETTER F
+        '\ufffe',    //       0x87 -> REVERSED LATIN SMALL LETTER G
+        '\ufffe',    //       0x88 -> REVERSED LATIN SMALL LETTER H
+        '\ufffe',    //       0x89 -> REVERSED LATIN SMALL LETTER I
+        '\ufffe',    //       0x8A -> REVERSED LATIN SMALL LETTER J
+        '\ufffe',    //       0x8B -> REVERSED LATIN SMALL LETTER K
+        '\ufffe',    //       0x8C -> REVERSED LATIN SMALL LETTER L
+        '\ufffe',    //       0x8D -> REVERSED LATIN SMALL LETTER M
+        '\ufffe',    //       0x8E -> REVERSED LATIN SMALL LETTER N
+        '\ufffe',    //       0x8F -> REVERSED LATIN SMALL LETTER O
+        '\ufffe',    //       0x90 -> REVERSED LATIN SMALL LETTER P
+        '\ufffe',    //       0x91 -> REVERSED LATIN SMALL LETTER Q
+        '\ufffe',    //       0x92 -> REVERSED LATIN SMALL LETTER R
+        '\ufffe',    //       0x93 -> REVERSED LATIN SMALL LETTER S
+        '\ufffe',    //       0x94 -> REVERSED LATIN SMALL LETTER T
+        '\ufffe',    //       0x95 -> REVERSED LATIN SMALL LETTER U
+        '\ufffe',    //       0x96 -> REVERSED LATIN SMALL LETTER V
+        '\ufffe',    //       0x97 -> REVERSED LATIN SMALL LETTER W
+        '\ufffe',    //       0x98 -> REVERSED LATIN SMALL LETTER X
+        '\ufffe',    //       0x99 -> REVERSED LATIN SMALL LETTER Y
+        '\ufffe',    //       0x9A -> REVERSED LATIN SMALL LETTER Z
+        '\ufffe',    //       0x9B -> REVERSED LEFT SQUARE BRACKET
+        '\ufffe',    //       0x9C -> REVERSED REVERSE SOLIDUS
+        '\ufffe',    //       0x9D -> REVERSED RIGHT SQUARE BRACKET
+        '\ufffe',    //       0x9E -> REVERSED CIRCUMFLEX
+        '\ufffe',    //       0x9F -> REVERSED UNDERSCORE
+        '\ufffe',    //       0xA0 -> REVERSED SPACE
+        '\ufffe',    //       0xA1 -> REVERSED EXCLAMATION MARK
+        '\ufffe',    //       0xA2 -> REVERSED QUOTATION MARK
+        '\ufffe',    //       0xA3 -> REVERSED NUMBER SIGN
+        '\ufffe',    //       0xA4 -> REVERSED DOLLAR SIGN
+        '\ufffe',    //       0xA5 -> REVERSED PERCENT SIGN
+        '\ufffe',    //       0xA6 -> REVERSED AMPERSAND
+        '\ufffe',    //       0xA7 -> REVERSED APOSTROPHE
+        '\ufffe',    //       0xA8 -> REVERSED LEFT PARENTHESIS
+        '\ufffe',    //       0xA9 -> REVERSED RIGHT PARENTHESIS
+        '\ufffe',    //       0xAA -> REVERSED ASTERISK
+        '\ufffe',    //       0xAB -> REVERSED PLUS SIGN
+        '\ufffe',    //       0xAC -> REVERSED COMMA
+        '\ufffe',    //       0xAD -> REVERSED HYPHEN-MINUS
+        '\ufffe',    //       0xAE -> REVERSED FULL STOP
+        '\ufffe',    //       0xAF -> REVERSED SOLIDUS
+        '\ufffe',    //       0xB0 -> REVERSED DIGIT ZERO
+        '\ufffe',    //       0xB1 -> REVERSED DIGIT ONE
+        '\ufffe',    //       0xB2 -> REVERSED DIGIT TWO
+        '\ufffe',    //       0xB3 -> REVERSED DIGIT THREE
+        '\ufffe',    //       0xB4 -> REVERSED DIGIT FOUR
+        '\ufffe',    //       0xB5 -> REVERSED DIGIT FIVE
+        '\ufffe',    //       0xB6 -> REVERSED DIGIT SIX
+        '\ufffe',    //       0xB7 -> REVERSED DIGIT SEVEN
+        '\ufffe',    //       0xB8 -> REVERSED DIGIT EIGHT
+        '\ufffe',    //       0xB9 -> REVERSED DIGIT NINE
+        '\ufffe',    //       0xBA -> REVERSED COLON
+        '\ufffe',    //       0xBB -> REVERSED SEMICOLON
+        '\ufffe',    //       0xBC -> REVERSED LESS-THAN SIGN
+        '\ufffe',    //       0xBD -> REVERSED EQUALS SIGN
+        '\ufffe',    //       0xBE -> REVERSED GREATER-THAN SIGN
+        '\ufffe',    //       0xBF -> REVERSED QUESTION MARK
+        '\ufffe',    //       0xC0 -> REVERSED GRAVE ACCENT
+        '\ufffe',    //       0xC1 -> REVERSED LATIN CAPITAL LETTER A
+        '\ufffe',    //       0xC2 -> REVERSED LATIN CAPITAL LETTER B
+        '\ufffe',    //       0xC3 -> REVERSED LATIN CAPITAL LETTER C
+        '\ufffe',    //       0xC4 -> REVERSED LATIN CAPITAL LETTER D
+        '\ufffe',    //       0xC5 -> REVERSED LATIN CAPITAL LETTER E
+        '\ufffe',    //       0xC6 -> REVERSED LATIN CAPITAL LETTER F
+        '\ufffe',    //       0xC7 -> REVERSED LATIN CAPITAL LETTER G
+        '\ufffe',    //       0xC8 -> REVERSED LATIN CAPITAL LETTER H
+        '\ufffe',    //       0xC9 -> REVERSED LATIN CAPITAL LETTER I
+        '\ufffe',    //       0xCA -> REVERSED LATIN CAPITAL LETTER J
+        '\ufffe',    //       0xCB -> REVERSED LATIN CAPITAL LETTER K
+        '\ufffe',    //       0xCC -> REVERSED LATIN CAPITAL LETTER L
+        '\ufffe',    //       0xCD -> REVERSED LATIN CAPITAL LETTER M
+        '\ufffe',    //       0xCE -> REVERSED LATIN CAPITAL LETTER N
+        '\ufffe',    //       0xCF -> REVERSED LATIN CAPITAL LETTER O
+        '\ufffe',    //       0xD0 -> REVERSED LATIN CAPITAL LETTER P
+        '\ufffe',    //       0xD1 -> REVERSED LATIN CAPITAL LETTER Q
+        '\ufffe',    //       0xD2 -> REVERSED LATIN CAPITAL LETTER R
+        '\ufffe',    //       0xD3 -> REVERSED LATIN CAPITAL LETTER S
+        '\ufffe',    //       0xD4 -> REVERSED LATIN CAPITAL LETTER T
+        '\ufffe',    //       0xD5 -> REVERSED LATIN CAPITAL LETTER U
+        '\ufffe',    //       0xD6 -> REVERSED LATIN CAPITAL LETTER V
+        '\ufffe',    //       0xD7 -> REVERSED LATIN CAPITAL LETTER W
+        '\ufffe',    //       0xD8 -> REVERSED LATIN CAPITAL LETTER X
+        '\ufffe',    //       0xD9 -> REVERSED LATIN CAPITAL LETTER Y
+        '\ufffe',    //       0xDA -> REVERSED LATIN CAPITAL LETTER Z
+        '\ufffe',    //       0xDB -> REVERSED LEFT BRACE
+        '\ufffe',    //       0xDC -> REVERSED VERTICAL BAR
+        '\ufffe',    //       0xDD -> REVERSED RIGHT BRACE
+        '\ufffe',    //       0xDE -> REVERSED TILDE
+        '\ufffe',    //       0xDF -> RESERVED
+        '\ufffe',    //       0xE0 -> RESERVED
+        '\ufffe',    //       0xE1 -> REVERSED COMMODORE SYMBOL
+        '\ufffe',    //       0xE2 -> REVERSED UP ARROW
+        '\ufffe',    //       0xE3 -> REVERSED DOWN ARROW
+        '\ufffe',    //       0xE4 -> REVERSED LEFT ARROW
+        '\ufffe',    //       0xE5 -> REVERSED RIGHT ARROW
+        '\ufffe',    //       0xE6 -> REVERSED ANALOG CLOCKFACE
+        '\ufffe',    //       0xE7 -> REVERSED CYCLE ARROWS
+        '\ufffe',    //       0xE8 -> REVERSED ELLIPSIS
+        '\ufffe',    //       0xE9 -> REVERSED DIAGONAL STRIPES
+        '\ufffe',    //       0xEA -> REVERSED CHECKBOX UNCHECKED
+        '\ufffe',    //       0xEB -> REVERSED CHECKBOX CHECKED
+        '\ufffe',    //       0xEC -> REVERSED RADIO BUTTON UNSELECTED
+        '\ufffe',    //       0xED -> REVERSED RADIO BUTTON SELECTED
+        '\ufffe',    //       0xEE -> MEMORY CHIP ICON
+        '\u21e7',    //  ⇧    0xEF -> SHIFT SYMBOL
+        '\ufffe',    //       0xF0 -> REVERSED COPYRIGHT SYMBOL
+        '\ufffe',    //       0xF1 -> REVERSED CHECKMARK
+        '\ufffe',    //       0xF2 -> REVERSED THREE HORIZONTAL STRIPES
+        '\ufffe',    //       0xF3 -> REVERSED TICK TRACK
+        '\ufffe',    //       0xF4 -> REVERSED TICK TRACK NUB
+        '\ufffe',    //       0xF5 -> REVERSED TAB CORNER
+        '\ufffe',    //       0xF6 -> REVERSED THREE VERTICAL STRIPES
+        '\ufffe',    //       0xF7 -> CUSTOM 10
+        '\ufffe',    //       0xF8 -> CUSTOM 11
+        '\ufffe',    //       0xF9 -> CUSTOM 12
+        '\ufffe',    //       0xFA -> CUSTOM 13
+        '\ufffe',    //       0xFB -> CUSTOM 14
+        '\ufffe',    //       0xFC -> CUSTOM 15
+        '\ufffe',    //       0xFD -> CUSTOM 16
+        '\ufffe',    //       0xFE -> CUSTOM 17
+        '\ufffe'     //       0xFF -> CUSTOM 18
+    )
+
+    // encoding:  from unicode to C64 OS Screencodes (0-255)
+    private val encodingC64os = decodingC64os.withIndex().associate{it.value to it.index}
+
+    private fun replaceSpecial(chr: Char): Char =
+        when(chr) {
+            '\r' -> '\n'        // to make \r (carriage returrn) equivalent to \n (line feed): RETURN ($0d)
+            else -> chr
+        }
+    
+    fun encode(text: String, lowercase: Boolean = false): Result<List<UByte>, CharConversionException> {
+        fun encodeChar(chr3: Char, lowercase: Boolean): UByte {
+            val chr = replaceSpecial(chr3)
+            val screencode = encodingC64os[chr]
+            return screencode?.toUByte() ?: when (chr) {
+                '\u0000' -> 0u
+                '\n' -> 13u
+                in '\u8000'..'\u80ff' -> {
+                    // special case: take the lower 8 bit hex value directly
+                    (chr.code - 0x8000).toUByte()
+                }
+                else -> {
+                    if(chr.isISOControl())
+                        throw CharConversionException("no c64os character for char #${chr.code}")
+                    else
+                        throw CharConversionException("no c64os character for char #${chr.code} '${chr}'")
+                }
+            }
+        }
+
+        return try {
+            Ok(text.map {
+                try {
+                    encodeChar(it, lowercase)
+                } catch (x: CharConversionException) {
+                    encodeChar(it, !lowercase)
+                }
+            })
+        } catch(cx: CharConversionException) {
+            Err(cx)
+        }
+    }
+
+    fun decode(screencode: Iterable<UByte>, lowercase: Boolean = false): Result<String, CharConversionException> {
+        return try {
+            Ok(screencode.map {
+                val code = it.toInt()
+                if(code<0 || code>= decodingC64os.size)
+                    throw CharConversionException("c64os $code out of range 0..${decodingC64os.size-1}")
+                decodingC64os[code]
+            }.joinToString(""))
+        } catch(ce: CharConversionException) {
+            Err(ce)
+        }
+    }
+}

codeCore/src/prog8/code/target/encodings/Cp437Encoding.kt

@@ -0,0 +1,69 @@
+package prog8.code.target.encodings
+
+import com.github.michaelbull.result.Err
+import com.github.michaelbull.result.Ok
+import com.github.michaelbull.result.Result
+import java.io.CharConversionException
+import java.nio.charset.Charset
+
+object Cp437Encoding {
+    val charset: Charset = Charset.forName("IBM437")
+
+    fun encode(str: String): Result<List<UByte>, CharConversionException> {
+        return try {
+            val mapped = str.map { chr ->
+                when (chr) {
+                    '\u0000' -> 0u
+                    '\u00a0' -> 255u
+                    '☺' -> 1u
+                    '☻' -> 2u
+                    '♥' -> 3u
+                    '♦' -> 4u
+                    '♣' -> 5u
+                    '♠' -> 6u
+                    '•' -> 7u
+                    '◘' -> 8u
+                    '○' -> 9u
+                    '◙' -> 10u
+                    '♂' -> 11u
+                    '♀' -> 12u
+                    '♪' -> 13u
+                    '♫' -> 14u
+                    '☼' -> 15u
+                    '►' -> 16u
+                    '◄' -> 17u
+                    '↕' -> 18u
+                    '‼' -> 19u
+                    '¶' -> 20u
+                    '§' -> 21u
+                    '▬' -> 22u
+                    '↨' -> 23u
+                    '↑' -> 24u
+                    '↓' -> 25u
+                    '→' -> 26u
+                    '←' -> 27u
+                    '∟' -> 28u
+                    '↔' -> 29u
+                    '▲' -> 30u
+                    '▼' -> 31u
+                    in '\u8000'..'\u80ff' -> {
+                        // special case: take the lower 8 bit hex value directly
+                        (chr.code - 0x8000).toUByte()
+                    }
+                    else -> charset.encode(chr.toString())[0].toUByte()
+                }
+            }
+            Ok(mapped)
+        } catch (ce: CharConversionException) {
+            Err(ce)
+        }
+    }
+
+    fun decode(bytes: Iterable<UByte>): Result<String, CharConversionException> {
+        return try {
+            Ok(String(bytes.map { it.toByte() }.toByteArray(), charset))
+        } catch (ce: CharConversionException) {
+            Err(ce)
+        }
+    }
+}

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

@@ -0,0 +1,47 @@
+package prog8.code.target.encodings
+
+import com.github.michaelbull.result.fold
+import prog8.code.core.Encoding
+import prog8.code.core.IStringEncoding
+import prog8.code.core.InternalCompilerException
+
+class Encoder(val newlineToCarriageReturn: Boolean): IStringEncoding {
+    override val defaultEncoding: Encoding = Encoding.ISO
+
+    override fun encodeString(str: String, encoding: Encoding): List<UByte> {
+        val coded = when(encoding) {
+            Encoding.PETSCII -> PetsciiEncoding.encodePetscii(str, true)
+            Encoding.SCREENCODES -> PetsciiEncoding.encodeScreencode(str, true)
+            Encoding.ISO -> IsoEncoding.encode(str, newlineToCarriageReturn)
+            Encoding.ISO5 -> IsoCyrillicEncoding.encode(str, newlineToCarriageReturn)
+            Encoding.ISO16 -> IsoEasternEncoding.encode(str, newlineToCarriageReturn)
+            Encoding.CP437 -> Cp437Encoding.encode(str)
+            Encoding.KATAKANA -> KatakanaEncoding.encode(str, newlineToCarriageReturn)
+            Encoding.ATASCII -> AtasciiEncoding.encode(str)
+            Encoding.C64OS -> C64osEncoding.encode(str)
+            else -> throw InternalCompilerException("unsupported encoding $encoding")
+        }
+        return coded.fold(
+            failure = { throw it },
+            success = { it }
+        )
+    }
+    override fun decodeString(bytes: Iterable<UByte>, encoding: Encoding): String {
+        val decoded = when(encoding) {
+            Encoding.PETSCII -> PetsciiEncoding.decodePetscii(bytes, true)
+            Encoding.SCREENCODES -> PetsciiEncoding.decodeScreencode(bytes, true)
+            Encoding.ISO -> IsoEncoding.decode(bytes, newlineToCarriageReturn)
+            Encoding.ISO5 -> IsoCyrillicEncoding.decode(bytes, newlineToCarriageReturn)
+            Encoding.ISO16 -> IsoEasternEncoding.decode(bytes, newlineToCarriageReturn)
+            Encoding.CP437 -> Cp437Encoding.decode(bytes)
+            Encoding.KATAKANA -> KatakanaEncoding.decode(bytes, newlineToCarriageReturn)
+            Encoding.ATASCII -> AtasciiEncoding.decode(bytes)
+            Encoding.C64OS -> C64osEncoding.decode(bytes)
+            else -> throw InternalCompilerException("unsupported encoding $encoding")
+        }
+        return decoded.fold(
+            failure = { throw it },
+            success = { it }
+        )
+    }
+}

codeCore/src/prog8/code/target/encodings/IsoEncoding.kt

@@ -0,0 +1,49 @@
+package prog8.code.target.encodings
+
+import com.github.michaelbull.result.Err
+import com.github.michaelbull.result.Ok
+import com.github.michaelbull.result.Result
+import java.io.CharConversionException
+import java.nio.charset.Charset
+
+
+open class IsoEncodingBase(charsetName: String) {
+    val charset: Charset = Charset.forName(charsetName)
+
+    fun encode(str: String, newlineToCarriageReturn: Boolean): Result<List<UByte>, CharConversionException> {
+        return try {
+            val mapped = str.map { chr ->
+                when (chr) {
+                    '\u0000' -> 0u
+                    '\n' -> if(newlineToCarriageReturn) 13u else 10u
+                    in '\u8000'..'\u80ff' -> {
+                        // special case: take the lower 8 bit hex value directly
+                        (chr.code - 0x8000).toUByte()
+                    }
+                    else -> charset.encode(chr.toString())[0].toUByte()
+                }
+            }
+            Ok(mapped)
+        } catch (ce: CharConversionException) {
+            Err(ce)
+        }
+    }
+
+    fun decode(bytes: Iterable<UByte>, newlineToCarriageReturn: Boolean): Result<String, CharConversionException> {
+        return try {
+            Ok(String(bytes.map {
+                when(it) {
+                    13u.toUByte() -> if(newlineToCarriageReturn) 10 else 13
+                    else -> it.toByte()
+                }
+            }.toByteArray(), charset))
+        } catch (ce: CharConversionException) {
+            Err(ce)
+        }
+    }
+}
+
+
+object IsoEncoding: IsoEncodingBase("ISO-8859-15")
+object IsoCyrillicEncoding: IsoEncodingBase("ISO-8859-5")
+object IsoEasternEncoding: IsoEncodingBase("ISO-8859-16")

codeCore/src/prog8/code/target/encodings/KatakanaEncoding.kt

@@ -0,0 +1,128 @@
+package prog8.code.target.encodings
+
+import com.github.michaelbull.result.Err
+import com.github.michaelbull.result.Ok
+import com.github.michaelbull.result.Result
+import java.io.CharConversionException
+import java.nio.charset.Charset
+
+
+object JapaneseCharacterConverter {
+    // adapted from https://github.com/raminduw/Japanese-Character-Converter
+
+    private val ZENKAKU_KATAKANA = charArrayOf(
+        'ァ', 'ア', 'ィ', 'イ', 'ゥ',
+        'ウ', 'ェ', 'エ', 'ォ', 'オ', 'カ', 'ガ', 'キ', 'ギ', 'ク', 'グ', 'ケ', 'ゲ',
+        'コ', 'ゴ', 'サ', 'ザ', 'シ', 'ジ', 'ス', 'ズ', 'セ', 'ゼ', 'ソ', 'ゾ', 'タ',
+        'ダ', 'チ', 'ヂ', 'ッ', 'ツ', 'ヅ', 'テ', 'デ', 'ト', 'ド', 'ナ', 'ニ', 'ヌ',
+        'ネ', 'ノ', 'ハ', 'バ', 'パ', 'ヒ', 'ビ', 'ピ', 'フ', 'ブ', 'プ', 'ヘ', 'ベ',
+        'ペ', 'ホ', 'ボ', 'ポ', 'マ', 'ミ', 'ム', 'メ', 'モ', 'ャ', 'ヤ', 'ュ', 'ユ',
+        'ョ', 'ヨ', 'ラ', 'リ', 'ル', 'レ', 'ロ', 'ヮ', 'ワ', 'ヰ', 'ヱ', 'ヲ', 'ン',
+        'ヴ', 'ヵ', 'ヶ'
+    )
+
+    private val HANKAKU_HIRAGANA = charArrayOf(
+        'ぁ', 'あ', 'ぃ', 'い', 'ぅ', 'う', 'ぇ', 'え',
+        'ぉ', 'お', 'か', 'が', 'き', 'ぎ', 'く', 'ぐ',
+        'け', 'げ', 'こ', 'ご', 'さ', 'ざ', 'し', 'じ',
+        'す', 'ず', 'せ', 'ぜ', 'そ', 'ぞ', 'た', 'だ',
+        'ち', 'ぢ', 'っ', 'つ', 'づ', 'て', 'で', 'と',
+        'ど', 'な', 'に', 'ぬ', 'ね', 'の', 'は', 'ば',
+        'ぱ', 'ひ', 'び', 'ぴ', 'ふ', 'ぶ', 'ぷ', 'へ',
+        'べ', 'ぺ', 'ほ', 'ぼ', 'ぽ', 'ま', 'み', 'む',
+        'め', 'も', 'ゃ', 'や', 'ゅ', 'ゆ', 'ょ', 'よ',
+        'ら', 'り', 'る', 'れ', 'ろ', 'ゎ', 'わ', 'ゐ',
+        'ゑ', 'を', 'ん', 'ゔ', 'ゕ', 'ゖ'
+    )
+
+    private val HANKAKU_KATAKANA = arrayOf(
+        "ｧ", "ｱ", "ｨ", "ｲ", "ｩ",
+        "ｳ", "ｪ", "ｴ", "ｫ", "ｵ", "ｶ", "ｶﾞ", "ｷ", "ｷﾞ", "ｸ", "ｸﾞ", "ｹ",
+        "ｹﾞ", "ｺ", "ｺﾞ", "ｻ", "ｻﾞ", "ｼ", "ｼﾞ", "ｽ", "ｽﾞ", "ｾ", "ｾﾞ", "ｿ",
+        "ｿﾞ", "ﾀ", "ﾀﾞ", "ﾁ", "ﾁﾞ", "ｯ", "ﾂ", "ﾂﾞ", "ﾃ", "ﾃﾞ", "ﾄ", "ﾄﾞ",
+        "ﾅ", "ﾆ", "ﾇ", "ﾈ", "ﾉ", "ﾊ", "ﾊﾞ", "ﾊﾟ", "ﾋ", "ﾋﾞ", "ﾋﾟ", "ﾌ",
+        "ﾌﾞ", "ﾌﾟ", "ﾍ", "ﾍﾞ", "ﾍﾟ", "ﾎ", "ﾎﾞ", "ﾎﾟ", "ﾏ", "ﾐ", "ﾑ", "ﾒ",
+        "ﾓ", "ｬ", "ﾔ", "ｭ", "ﾕ", "ｮ", "ﾖ", "ﾗ", "ﾘ", "ﾙ", "ﾚ", "ﾛ", "ﾜ",
+        "ﾜ", "ｲ", "ｴ", "ｦ", "ﾝ", "ｳﾞ", "ｶ", "ｹ"
+    )
+
+    private val ZENKAKU_KATAKANA_FIRST_CHAR_CODE = ZENKAKU_KATAKANA.first().code
+    private val HANKAKU_HIRAGANA_FIRST_CHAR_CODE = HANKAKU_HIRAGANA.first().code
+
+    private fun zenkakuKatakanaToHankakuKatakana(c: Char): String = if (c in ZENKAKU_KATAKANA) HANKAKU_KATAKANA[c.code - ZENKAKU_KATAKANA_FIRST_CHAR_CODE] else c.toString()
+    private fun hankakuKatakanaToZenkakuKatakana(c: Char): Char = if (c in HANKAKU_HIRAGANA) ZENKAKU_KATAKANA[c.code - HANKAKU_HIRAGANA_FIRST_CHAR_CODE] else c
+
+    fun zenkakuKatakanaToHankakuKatakana(s: String): String = buildString {
+        for (element in s) {
+            val converted = hankakuKatakanaToZenkakuKatakana(element)
+            val convertedChar = zenkakuKatakanaToHankakuKatakana(converted)
+            append(convertedChar)
+        }
+    }
+}
+
+object KatakanaEncoding {
+    val charset: Charset = Charset.forName("JIS_X0201")
+
+    fun encode(str: String, newlineToCarriageReturn: Boolean): Result<List<UByte>, CharConversionException> {
+        return try {
+            val mapped = str.map { chr ->
+                when (chr) {
+                    '\n' -> if(newlineToCarriageReturn) 13u else 10u
+
+                    '\u0000' -> 0u
+                    '\u00a0' -> 0xa0u // $a0 isn't technically a part of JIS X 0201 spec, and so we need to handle this ourselves
+
+                    '♥' -> 0xe3u
+                    '♦' -> 0xe4u
+                    '♣' -> 0xe5u
+                    '♠' -> 0xe6u
+
+                    '大' -> 0xeau
+                    '中' -> 0xebu
+                    '小' -> 0xecu
+                    '百' -> 0xedu
+                    '千' -> 0xeeu
+                    '万' -> 0xefu
+                    '♪' -> 0xf0u
+                    '土' -> 0xf1u
+                    '金' -> 0xf2u
+                    '木' -> 0xf3u
+                    '水' -> 0xf4u
+                    '火' -> 0xf5u
+                    '月' -> 0xf6u
+                    '日' -> 0xf7u
+                    '時' -> 0xf8u
+                    '分' -> 0xf9u
+                    '秒' -> 0xfau
+                    '年' -> 0xfbu
+                    '円' -> 0xfcu
+                    '人' -> 0xfdu
+                    '生' -> 0xfeu
+                    '〒' -> 0xffu
+                    in '\u8000'..'\u80ff' -> {
+                        // special case: take the lower 8 bit hex value directly
+                        (chr.code - 0x8000).toUByte()
+                    }
+                    else -> charset.encode(chr.toString())[0].toUByte()
+                }
+            }
+            Ok(mapped)
+        } catch (ce: CharConversionException) {
+            Err(ce)
+        }
+    }
+
+    fun decode(bytes: Iterable<UByte>, newlineToCarriageReturn: Boolean): Result<String, CharConversionException> {
+        return try {
+            Ok(String(bytes.map {
+                when(it) {
+                    13u.toUByte() -> if(newlineToCarriageReturn) 10 else 13
+                    else -> it.toByte()
+                }
+            }.toByteArray(), charset))
+        } catch (ce: CharConversionException) {
+            Err(ce)
+        }
+    }
+}

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

@@ -1,14 +1,13 @@
-package prog8.codegen.target.cbm
+package prog8.code.target.encodings
 
 import com.github.michaelbull.result.Err
 import com.github.michaelbull.result.Ok
 import com.github.michaelbull.result.Result
-import prog8.ast.antlr.escape
 import java.io.CharConversionException
 
 object PetsciiEncoding {
 
-    // decoding:  from Petscii/Screencodes (0-255) to unicode
+    // decoding:  from Petscii/Screencodes (0-255) to Unicode
     // character tables used from https://github.com/irmen/cbmcodecs2
 
     private val decodingPetsciiLowercase = charArrayOf(
@@ -22,10 +21,10 @@ object PetsciiEncoding {
         '\ufffe',    //       0x07 -> UNDEFINED
         '\uf118',    //       0x08 -> DISABLE CHARACTER SET SWITCHING (CUS)
         '\uf119',    //       0x09 -> ENABLE CHARACTER SET SWITCHING (CUS)
-        '\ufffe',    //       0x0A -> UNDEFINED
+        '\n',        //       0x0A -> LINE FEED (RETURN)
         '\ufffe',    //       0x0B -> UNDEFINED
         '\ufffe',    //       0x0C -> UNDEFINED
-        '\r'    ,    //       0x0D -> CARRIAGE RETURN
+        '\n'    ,    //       0x0D -> LINE FEED (RETURN)
         '\u000e',    //       0x0E -> SHIFT OUT
         '\ufffe',    //       0x0F -> UNDEFINED
         '\ufffe',    //       0x10 -> UNDEFINED
@@ -153,13 +152,13 @@ object PetsciiEncoding {
         '\uf113',    //      0x8A -> FUNCTION KEY 4 (CUS)
         '\uf115',    //      0x8B -> FUNCTION KEY 6 (CUS)
         '\uf117',    //      0x8C -> FUNCTION KEY 8 (CUS)
-        '\n'    ,    //       0x8D -> LINE FEED
+        '\r'    ,    //       0x8D -> CARRIAGE RETURN (SHIFT-RETURN)
         '\u000f',    //      0x8E -> SHIFT IN
         '\ufffe',    //       0x8F -> UNDEFINED
         '\uf105',    //       0x90 -> BLACK COLOR SWITCH (CUS)
         '\uf11e',    //      0x91 -> CURSOR UP (CUS)
         '\uf11b',    //      0x92 -> REVERSE VIDEO OFF (CUS)
-        '\u000c',    //       0x93 -> FORM FEED
+        '\u000c',    //       0x93 -> FORM FEED (CLEAR SCREEN)
         '\uf121',    //      0x94 -> INSERT (CUS)
         '\uf106',    //       0x95 -> BROWN COLOR SWITCH (CUS)
         '\uf107',    //       0x96 -> LIGHT RED COLOR SWITCH (CUS)
@@ -195,7 +194,7 @@ object PetsciiEncoding {
         '\u258e',    //  ▎    0xB4 -> LEFT ONE QUARTER BLOCK
         '\u258d',    //  ▍    0xB5 -> LEFT THREE EIGTHS BLOCK
         '\uf131',    //      0xB6 -> RIGHT THREE EIGHTHS BLOCK (CUS)
-        '\uf132',    //      0xB7 -> UPPER ONE QUARTER BLOCK (CUS)
+        '\uf132',    //  🮂    0xB7 -> UPPER ONE QUARTER BLOCK (CUS)
         '\uf133',    //      0xB8 -> UPPER THREE EIGHTS BLOCK (CUS)
         '\u2583',    //  ▃    0xB9 -> LOWER THREE EIGHTHS BLOCK
         '\u2713',    //  ✓    0xBA -> CHECK MARK
@@ -246,7 +245,7 @@ object PetsciiEncoding {
         '\u2595',    //  ▕    0xE7 -> RIGHT ONE EIGHTH BLOCK
         '\uf12f',    //      0xE8 -> LOWER HALF BLOCK MEDIUM SHADE (CUS)
         '\uf13a',    //      0xE9 -> MEDIUM SHADE SLASHED RIGHT (CUS)
-        '\uf130',    //      0xEA -> RIGHT ONE QUARTER BLOCK (CUS)
+        '\uf130',    //  🮇    0xEA -> RIGHT ONE QUARTER BLOCK (CUS)
         '\u251c',    //  ├    0xEB -> BOX DRAWINGS LIGHT VERTICAL AND RIGHT
         '\u2597',    //  ▗    0xEC -> QUADRANT LOWER RIGHT
         '\u2514',    //  └    0xED -> BOX DRAWINGS LIGHT UP AND RIGHT
@@ -284,7 +283,7 @@ object PetsciiEncoding {
         '\ufffe',    //       0x0A -> UNDEFINED
         '\ufffe',    //       0x0B -> UNDEFINED
         '\ufffe',    //       0x0C -> UNDEFINED
-        '\r'    ,    //       0x0D -> CARRIAGE RETURN
+        '\n'    ,    //       0x0D -> LINE FEED (RETURN)
         '\u000e',    //       0x0E -> SHIFT OUT
         '\ufffe',    //       0x0F -> UNDEFINED
         '\ufffe',    //       0x10 -> UNDEFINED
@@ -412,13 +411,13 @@ object PetsciiEncoding {
         '\uf113',    //       0x8A -> FUNCTION KEY 4 (CUS)
         '\uf115',    //       0x8B -> FUNCTION KEY 6 (CUS)
         '\uf117',    //       0x8C -> FUNCTION KEY 8 (CUS)
-        '\n'    ,    //       0x8D -> LINE FEED
+        '\r'    ,    //       0x8D -> CARRIAGE RETURN (SHIFT-RETURN)
         '\u000f',    //       0x8E -> SHIFT IN
         '\ufffe',    //       0x8F -> UNDEFINED
         '\uf105',    //       0x90 -> BLACK COLOR SWITCH (CUS)
         '\uf11e',    //       0x91 -> CURSOR UP (CUS)
         '\uf11b',    //       0x92 -> REVERSE VIDEO OFF (CUS)
-        '\u000c',    //       0x93 -> FORM FEED
+        '\u000c',    //       0x93 -> FORM FEED (CLEAR SCREEN)
         '\uf121',    //       0x94 -> INSERT (CUS)
         '\uf106',    //       0x95 -> BROWN COLOR SWITCH (CUS)
         '\uf107',    //       0x96 -> LIGHT RED COLOR SWITCH (CUS)
@@ -1062,6 +1061,7 @@ object PetsciiEncoding {
             '}' -> '├'
             '|' -> '│'
             '\\' -> '╲'
+            '\r' -> '\n'        // to make \r (carriage returrn) equivalent to \n (line feed): RETURN ($0d)
             else -> chr
         }
 
@@ -1077,7 +1077,10 @@ object PetsciiEncoding {
                 }
                 else -> {
                     val case = if (lowercase) "lower" else "upper"
-                    throw CharConversionException("no ${case}Petscii character for '${escape(chr.toString())}' (${chr.code})")
+                    if(chr.isISOControl())
+                        throw CharConversionException("no ${case}Petscii character for char #${chr.code}")
+                    else
+                        throw CharConversionException("no ${case}Petscii character for char #${chr.code} '${chr}'")
                 }
             }
         }
@@ -1086,7 +1089,7 @@ object PetsciiEncoding {
             Ok(text.map {
                 try {
                     encodeChar(it, lowercase)
-                } catch (x: CharConversionException) {
+                } catch (_: CharConversionException) {
                     encodeChar(it, !lowercase)
                 }
             })
@@ -1114,13 +1117,18 @@ object PetsciiEncoding {
             val screencode = if(lowercase) encodingScreencodeLowercase[chr] else encodingScreencodeUppercase[chr]
             return screencode?.toUByte() ?: when (chr) {
                 '\u0000' -> 0u
+                '\n' -> 141u
+                '\r' -> 141u
                 in '\u8000'..'\u80ff' -> {
                     // special case: take the lower 8 bit hex value directly
                     (chr.code - 0x8000).toUByte()
                 }
                 else -> {
                     val case = if (lowercase) "lower" else "upper"
-                    throw CharConversionException("no ${case}Screencode character for '${escape(chr.toString())}' (${chr.code})")
+                    if(chr.isISOControl())
+                        throw CharConversionException("no ${case}Screencode character for char #${chr.code}")
+                    else
+                        throw CharConversionException("no ${case}Screencode character for char #${chr.code} '${chr}'")
                 }
             }
         }
@@ -1129,7 +1137,7 @@ object PetsciiEncoding {
             Ok(text.map {
                 try {
                     encodeChar(it, lowercase)
-                } catch (x: CharConversionException) {
+                } catch (_: CharConversionException) {
                     encodeChar(it, !lowercase)
                 }
             })
@@ -1151,16 +1159,16 @@ object PetsciiEncoding {
         }
     }
 
-    fun petscii2scr(petscii_code: UByte, inverseVideo: Boolean): Result<UByte, CharConversionException> {
+    fun petscii2scr(petsciicode: UByte, inverseVideo: Boolean): Result<UByte, CharConversionException> {
         val code: UInt = when {
-            petscii_code <= 0x1fu -> petscii_code + 128u
-            petscii_code <= 0x3fu -> petscii_code.toUInt()
-            petscii_code <= 0x5fu -> petscii_code - 64u
-            petscii_code <= 0x7fu -> petscii_code - 32u
-            petscii_code <= 0x9fu -> petscii_code + 64u
-            petscii_code <= 0xbfu -> petscii_code - 64u
-            petscii_code <= 0xfeu -> petscii_code - 128u
-            petscii_code == 255.toUByte() -> 95u
+            petsciicode <= 0x1fu -> petsciicode + 128u
+            petsciicode <= 0x3fu -> petsciicode.toUInt()
+            petsciicode <= 0x5fu -> petsciicode - 64u
+            petsciicode <= 0x7fu -> petsciicode - 32u
+            petsciicode <= 0x9fu -> petsciicode + 64u
+            petsciicode <= 0xbfu -> petsciicode - 64u
+            petsciicode <= 0xfeu -> petsciicode - 128u
+            petsciicode == 255.toUByte() -> 95u
             else -> return Err(CharConversionException("petscii code out of range"))
         }
         if(inverseVideo) {

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

@@ -0,0 +1,68 @@
+package prog8.code.target.zp
+
+import prog8.code.core.CompilationOptions
+import prog8.code.core.InternalCompilerException
+import prog8.code.core.Zeropage
+import prog8.code.core.ZeropageType
+
+
+// reference: "Mapping the C128" zeropage chapter.
+
+class C128Zeropage(options: CompilationOptions) : Zeropage(options) {
+
+    override val SCRATCH_B1 = 0x74u      // temp storage for a single byte
+    override val SCRATCH_REG = 0x75u     // temp storage for a register byte, must be B1+1
+    override val SCRATCH_W1 = 0xfbu      // temp storage 1 for a word  $fb+$fc
+    override val SCRATCH_W2 = 0xfdu      // temp storage 2 for a word  $fd+$fe
+
+    init {
+        if (options.floats && options.zeropage !in arrayOf(
+                ZeropageType.FLOATSAFE,
+                ZeropageType.BASICSAFE,
+                ZeropageType.DONTUSE
+            ))
+            throw InternalCompilerException("when floats are enabled, zero page type should be 'floatsafe' or 'basicsafe' or 'dontuse'")
+
+        when (options.zeropage) {
+            ZeropageType.FULL -> {
+                // $00/$01 are data port IO registers, // $02-$09 are storage locations for JSRFAR and such
+                free.addAll(0x0au..0xffu)
+                free.removeAll(arrayOf(0x90u, 0x91u, 0xa0u, 0xa1u, 0xa2u, 0xc0u, 0xccu, 0xcdu, 0xd0u, 0xd1u, 0xd2u, 0xd3u, 0xd4u, 0xd5u, 0xf7u))        // these are updated/used by IRQ
+            }
+            ZeropageType.KERNALSAFE -> {
+                free.addAll(0x0au..0x8fu)       // BASIC variables
+                free.addAll(arrayOf(0x92u, 0x96u, 0x9bu, 0x9cu, 0x9eu, 0x9fu, 0xa4u, 0xa7u, 0xa8u, 0xa9u, 0xaau, 0xabu,
+                    0xb0u, 0xb1u, 0xb4u, 0xb5u, 0xb6u))
+            }
+            ZeropageType.FLOATSAFE,
+            ZeropageType.BASICSAFE -> {
+                free.addAll(arrayOf(0x0bu, 0x0cu, 0x0du, 0x0eu, 0x0fu, 0x10u, 0x11u, 0x12u, 0x16u, 0x17u, 0x18u, 0x19u, 0x1au))
+                free.addAll(0x1bu..0x23u)
+                free.addAll(arrayOf(0x3fu, 0x40u, 0x41u, 0x42u, 0x43u, 0x44u, 0x47u, 0x48u, 0x49u, 0x4au, 0x4bu, 0x4cu, 0x4fu,
+                    0x55u, 0x56u, 0x57u, 0x58u,
+                    0x74u, 0x75u, 0x78u, 0x80u, 0x83u, 0x87u, 0x88u, 0x89u, 0x8au, 0x8bu, 0x8cu, 0x8du, 0x8eu, 0x8fu,
+                    0x92u, 0x96u, 0x9bu, 0x9cu, 0x9eu, 0x9fu, 0xa4u, 0xa7u, 0xa8u, 0xa9u, 0xaau, 0xabu,
+                    0xb0u, 0xb1u, 0xb4u, 0xb5u, 0xb6u
+                ))
+
+                // if(options.zeropage==ZeropageType.BASICSAFE) {
+                    // can also clobber the FP locations (unconditionally, because the C128 target doesn't support floating point calculations in prog8 at this time0
+                    free.addAll(arrayOf(0x14u, 0x28u, 0x29u, 0x2au, 0x2bu, 0x2cu,
+                        0x50u, 0x51u, 0x52u, 0x53u, 0x54u, 0x59u, 0x5au, 0x5bu, 0x5cu, 0x5du, 0x5eu, 0x5fu, 0x60u, 0x61u, 0x62u,
+                        0x63u, 0x64u, 0x65u, 0x66u, 0x67u, 0x68u,
+                        0x6au, 0x6bu, 0x6cu, 0x6du, 0x6eu, 0x6fu, 0x71u))
+                // }
+            }
+            ZeropageType.DONTUSE -> {
+                free.clear()  // don't use zeropage at all
+            }
+        }
+
+        val distinctFree = free.distinct()
+        free.clear()
+        free.addAll(distinctFree)
+
+        removeReservedFromFreePool()
+        retainAllowed()
+    }
+}

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

@@ -0,0 +1,98 @@
+package prog8.code.target.zp
+
+import prog8.code.core.*
+
+
+class C64Zeropage(options: CompilationOptions) : Zeropage(options) {
+
+    override val SCRATCH_B1 = 0x02u      // temp storage for a single byte
+    override val SCRATCH_REG = 0x03u     // temp storage for a register byte, must be B1+1
+    override val SCRATCH_W1 = 0xfbu      // temp storage 1 for a word  $fb+$fc
+    override val SCRATCH_W2 = 0xfdu      // temp storage 2 for a word  $fd+$fe
+
+
+    init {
+        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(0x02u..0xffu)
+            free.removeAll(arrayOf(SCRATCH_B1, SCRATCH_REG, SCRATCH_W1, SCRATCH_W1+1u, SCRATCH_W2, SCRATCH_W2+1u))
+            free.removeAll(arrayOf(0xa0u, 0xa1u, 0xa2u, 0x91u, 0xc0u, 0xc5u, 0xcbu, 0xf5u, 0xf6u))        // these are updated by IRQ
+        } else {
+            if (options.zeropage == ZeropageType.KERNALSAFE || options.zeropage == ZeropageType.FLOATSAFE) {
+                free.addAll(arrayOf(
+                        0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
+                        0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
+                        0x20, 0x21, 0x22, 0x23, 0x24, 0x25,
+                        0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f, 0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46,
+                        0x47, 0x48, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f, 0x51, 0x52, 0x53,
+                        0x57, 0x58, 0x59, 0x5a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f, 0x60,
+                        0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68,
+                        0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f, 0x70, 0x71, 0x72,
+                        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 'kernal work storage area'
+                ).map{it.toUInt()})
+            }
+
+            if (options.zeropage == ZeropageType.FLOATSAFE) {
+                // remove the zeropage locations used for floating point operations from the free list
+                free.removeAll(arrayOf(
+                        0x03, 0x04, 0x05, 0x06, 0x10, 0x11, 0x12,
+                        0x22, 0x23, 0x24, 0x25, 0x26, 0x27, 0x28, 0x29, 0x2a,
+                        0x57, 0x58, 0x59, 0x5a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f, 0x60,
+                        0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68,
+                        0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f, 0x70, 0x71, 0x72,
+                        0x8b, 0x8c, 0x8d, 0x8e, 0x8f, 0xff
+                ).map{it.toUInt()})
+            }
+
+            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(arrayOf(0x02, 0x03, 0x04, 0x05, 0x06, 0x0a, 0x0e,
+                        0x92, 0x96, 0x9b, 0x9c, 0x9e, 0x9f, 0xa6,
+                        0xb0, 0xb1, 0xbe, 0xbf, 0xf9).map{it.toUInt()})
+            } else {
+                // don't use the zeropage at all
+                free.clear()
+            }
+        }
+
+        val distinctFree = free.distinct()
+        free.clear()
+        free.addAll(distinctFree)
+
+        removeReservedFromFreePool()
+
+        if(options.zeropage==ZeropageType.FULL || options.zeropage==ZeropageType.KERNALSAFE) {
+            // in these cases there is enough space on the zero page to stick the cx16 virtual registers in there as well.
+            allocateCx16VirtualRegisters()
+        }
+
+        retainAllowed()
+    }
+
+    private fun allocateCx16VirtualRegisters() {
+        // Note: the 16 virtual registers R0-R15 are not regular allocated variables, they're *memory mapped* elsewhere to fixed addresses.
+        // However, to be able for the compiler to "see" them as zeropage variables, we have to register them here as well.
+        // This is important because the compiler sometimes treats ZP variables more efficiently (for example if it's a pointer)
+        // The base addres is $04.  Unfortunately it cannot be the same as on the Commander X16 ($02).
+        for(reg in 0..15) {
+            allocatedVariables["cx16.r${reg}"]   = VarAllocation((4+reg*2).toUInt(), DataType.UWORD, 2)       // cx16.r0 .. cx16.r15
+            allocatedVariables["cx16.r${reg}s"]  = VarAllocation((4+reg*2).toUInt(), DataType.WORD, 2)        // cx16.r0s .. cx16.r15s
+            allocatedVariables["cx16.r${reg}L"]  = VarAllocation((4+reg*2).toUInt(), DataType.UBYTE, 1)       // cx16.r0L .. cx16.r15L
+            allocatedVariables["cx16.r${reg}H"]  = VarAllocation((5+reg*2).toUInt(), DataType.UBYTE, 1)       // cx16.r0H .. cx16.r15H
+            allocatedVariables["cx16.r${reg}sL"] = VarAllocation((4+reg*2).toUInt(), DataType.BYTE, 1)        // cx16.r0sL .. cx16.r15sL
+            allocatedVariables["cx16.r${reg}sH"] = VarAllocation((5+reg*2).toUInt(), DataType.BYTE, 1)        // cx16.r0sH .. cx16.r15sH
+            free.remove((4+reg*2).toUInt())
+            free.remove((5+reg*2).toUInt())
+        }
+    }
+}

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

@@ -0,0 +1,68 @@
+package prog8.code.target.zp
+
+import prog8.code.core.*
+
+
+class CX16Zeropage(options: CompilationOptions) : Zeropage(options) {
+
+    override val SCRATCH_B1 = 0x7au      // temp storage for a single byte
+    override val SCRATCH_REG = 0x7bu     // temp storage for a register byte, must be B1+1
+    override val SCRATCH_W1 = 0x7cu      // temp storage 1 for a word  $7c+$7d
+    override val SCRATCH_W2 = 0x7eu      // temp storage 2 for a word  $7e+$7f
+
+
+    init {
+        if (options.floats && options.zeropage !in arrayOf(
+                ZeropageType.FLOATSAFE,
+                ZeropageType.BASICSAFE,
+                ZeropageType.DONTUSE
+            ))
+            throw InternalCompilerException("when floats are enabled, zero page type should be 'floatsafe' or 'basicsafe' or 'dontuse'")
+
+        // the addresses 0x02 to 0x21 (inclusive) are taken for sixteen virtual 16-bit api registers.
+
+        synchronized(this) {
+            when (options.zeropage) {
+                ZeropageType.FULL -> {
+                    free.addAll(0x22u..0xffu)
+                }
+                ZeropageType.KERNALSAFE -> {
+                    free.addAll(0x22u..0x7fu)
+                    free.addAll(0xa9u..0xffu)
+                }
+                ZeropageType.FLOATSAFE -> {
+                    free.addAll(0x22u..0x7fu)
+                    free.addAll(0xd4u..0xffu)
+                }
+                ZeropageType.BASICSAFE -> {
+                    free.addAll(0x22u..0x7fu)
+                }
+                ZeropageType.DONTUSE -> {
+                    free.clear() // don't use zeropage at all
+                }
+            }
+
+            val distinctFree = free.distinct()
+            free.clear()
+            free.addAll(distinctFree)
+
+            removeReservedFromFreePool()
+            allocateCx16VirtualRegisters()
+            retainAllowed()
+        }
+    }
+
+    private fun allocateCx16VirtualRegisters() {
+        // Note: the 16 virtual registers R0-R15 are not regular allocated variables, they're *memory mapped* elsewhere to fixed addresses.
+        // However, to be able for the compiler to "see" them as zeropage variables, we have to register them here as well.
+        // This is important because the compiler sometimes treats ZP variables more efficiently (for example if it's a pointer)
+        for(reg in 0..15) {
+            allocatedVariables["cx16.r${reg}"]   = VarAllocation((2+reg*2).toUInt(), DataType.UWORD, 2)       // cx16.r0 .. cx16.r15
+            allocatedVariables["cx16.r${reg}s"]  = VarAllocation((2+reg*2).toUInt(), DataType.WORD, 2)        // cx16.r0s .. cx16.r15s
+            allocatedVariables["cx16.r${reg}L"]  = VarAllocation((2+reg*2).toUInt(), DataType.UBYTE, 1)       // cx16.r0L .. cx16.r15L
+            allocatedVariables["cx16.r${reg}H"]  = VarAllocation((3+reg*2).toUInt(), DataType.UBYTE, 1)       // cx16.r0H .. cx16.r15H
+            allocatedVariables["cx16.r${reg}sL"] = VarAllocation((2+reg*2).toUInt(), DataType.BYTE, 1)        // cx16.r0sL .. cx16.r15sL
+            allocatedVariables["cx16.r${reg}sH"] = VarAllocation((3+reg*2).toUInt(), DataType.BYTE, 1)        // cx16.r0sH .. cx16.r15sH
+        }
+    }
+}

codeCore/src/prog8/code/target/zp/ConfigurableZeropage.kt

@@ -0,0 +1,61 @@
+package prog8.code.target.zp
+
+import prog8.code.core.CompilationOptions
+import prog8.code.core.DataType
+import prog8.code.core.Zeropage
+import prog8.code.core.ZeropageType
+
+class ConfigurableZeropage(
+    override val SCRATCH_B1: UInt,      // temp storage for a single byte
+    override val SCRATCH_REG: UInt,     // temp storage for a register byte, must be B1+1
+    override val SCRATCH_W1: UInt,      // temp storage 1 for a word
+    override val SCRATCH_W2: UInt,      // temp storage 2 for a word
+    val virtualRegistersStart: UInt,        // location of 32 bytes for the r0-r15 virtual registers
+    basicsafe: List<UIntRange>,
+    kernalsafe: List<UIntRange>,
+    fullsafe: List<UIntRange>,
+    options: CompilationOptions
+) : Zeropage(options) {
+
+    init {
+        if (options.floats) {
+            TODO("floats in configurable target zp")
+        }
+
+        if(SCRATCH_REG!=SCRATCH_B1+1u)
+            throw IllegalArgumentException("Zero page scratch variable REG should be B1+1")
+
+        when (options.zeropage) {
+            ZeropageType.DONTUSE -> { /* don't use any zeropage at all */ }
+            ZeropageType.FULL -> fullsafe.forEach { free.addAll(it) }
+            ZeropageType.BASICSAFE -> basicsafe.forEach { free.addAll(it) }
+            ZeropageType.KERNALSAFE -> kernalsafe.forEach { free.addAll(it) }
+            ZeropageType.FLOATSAFE -> TODO("floatsafe in configurable target zp")
+        }
+
+        val distinctFree = free.distinct()
+        free.clear()
+        free.addAll(distinctFree)
+
+        removeReservedFromFreePool()
+        allocateCx16VirtualRegisters()
+        retainAllowed()
+    }
+
+    private fun allocateCx16VirtualRegisters() {
+        // Note: the 16 virtual registers R0-R15 are not regular allocated variables, they're *memory mapped* elsewhere to fixed addresses.
+        // However, to be able for the compiler to "see" them as zeropage variables, we have to register them here as well.
+        // This is important because the compiler sometimes treats ZP variables more efficiently (for example if it's a pointer)
+        for(reg in 0..15) {
+            val address = virtualRegistersStart + (2*reg).toUInt()
+            if(address<=0xffu) {
+                allocatedVariables["cx16.r${reg}"]   = VarAllocation(address, DataType.UWORD, 2)       // cx16.r0 .. cx16.r15
+                allocatedVariables["cx16.r${reg}s"]  = VarAllocation(address, DataType.WORD, 2)        // cx16.r0s .. cx16.r15s
+                allocatedVariables["cx16.r${reg}L"]  = VarAllocation(address, DataType.UBYTE, 1)       // cx16.r0L .. cx16.r15L
+                allocatedVariables["cx16.r${reg}H"]  = VarAllocation(address+1u, DataType.UBYTE, 1)    // cx16.r0H .. cx16.r15H
+                allocatedVariables["cx16.r${reg}sL"] = VarAllocation(address, DataType.BYTE, 1)        // cx16.r0sL .. cx16.r15sL
+                allocatedVariables["cx16.r${reg}sH"] = VarAllocation(address+1u, DataType.BYTE, 1)     // cx16.r0sH .. cx16.r15sH
+            }
+        }
+    }
+}

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

@@ -0,0 +1,51 @@
+package prog8.code.target.zp
+
+import prog8.code.core.CompilationOptions
+import prog8.code.core.InternalCompilerException
+import prog8.code.core.Zeropage
+import prog8.code.core.ZeropageType
+
+
+// reference: http://www.zimmers.net/cbmpics/cbm/PETx/petmem.txt
+
+class PETZeropage(options: CompilationOptions) : Zeropage(options) {
+
+    override val SCRATCH_B1 = 0xb3u      // temp storage for a single byte
+    override val SCRATCH_REG = 0xb4u     // temp storage for a register byte, must be B1+1
+    override val SCRATCH_W1 = 0xb6u      // temp storage 1 for a word
+    override val SCRATCH_W2 = 0xb8u      // temp storage 2 for a word
+
+    init {
+        if (options.floats && options.zeropage !in arrayOf(
+                ZeropageType.FLOATSAFE,
+                ZeropageType.BASICSAFE,
+                ZeropageType.DONTUSE
+            ))
+            throw InternalCompilerException("when floats are enabled, zero page type should be 'floatsafe' or 'basicsafe' or 'dontuse'")
+
+        when (options.zeropage) {
+            ZeropageType.FULL -> {
+                free.addAll(0x00u..0xffu)
+                free.removeAll(listOf(0x8du, 0x8eu, 0x8fu, 0x97u, 0x98u, 0x99u, 0x9au, 0x9bu, 0x9eu, 0xa7u, 0xa8u, 0xa9u, 0xaau))        // these are updated/used by IRQ
+            }
+            ZeropageType.KERNALSAFE -> {
+                free.addAll(0x00u..0xffu)
+                free.removeAll(listOf(0x8du, 0x8eu, 0x8fu, 0x97u, 0x98u, 0x99u, 0x9au, 0x9bu, 0x9eu, 0xa7u, 0xa8u, 0xa9u, 0xaau))        // these are updated/used by IRQ
+            }
+            ZeropageType.FLOATSAFE,
+            ZeropageType.BASICSAFE -> {
+                free.addAll(0xb3u..0xbau)       // TODO more?
+            }
+            ZeropageType.DONTUSE -> {
+                free.clear()  // don't use zeropage at all
+            }
+        }
+
+        val distinctFree = free.distinct()
+        free.clear()
+        free.addAll(distinctFree)
+
+        removeReservedFromFreePool()
+        retainAllowed()
+    }
+}

codeGenCpu6502/build.gradle.kts

@@ -0,0 +1,47 @@
+import org.jetbrains.kotlin.gradle.dsl.JvmTarget
+
+plugins {
+    kotlin("jvm")
+}
+
+dependencies {
+    implementation(project(":codeCore"))
+    implementation(project(":simpleAst"))
+    // implementation("org.jetbrains.kotlin:kotlin-stdlib-jdk8")
+    // implementation "org.jetbrains.kotlin:kotlin-reflect"
+    implementation("com.michael-bull.kotlin-result:kotlin-result-jvm:2.0.1")
+
+    testImplementation("io.kotest:kotest-runner-junit5-jvm:5.9.1")
+    testImplementation("io.kotest:kotest-framework-datatest:5.9.1")
+    testImplementation("org.junit.jupiter:junit-jupiter:5.9.1")
+    testRuntimeOnly("org.junit.platform:junit-platform-launcher")
+}
+
+sourceSets {
+    main {
+        java {
+            setSrcDirs(listOf("$projectDir/src"))
+        }
+        resources {
+            setSrcDirs(listOf("$projectDir/res"))
+        }
+    }
+    test {
+        java {
+            setSrcDirs(listOf("$projectDir/test"))
+        }
+    }
+}
+
+tasks.test {
+    // Enable JUnit 5 (Gradle 4.6+).
+    useJUnitPlatform()
+
+    // Always run tests, even when nothing changed.
+    dependsOn("cleanTest")
+
+    // Show test results.
+    testLogging {
+        events("skipped", "failed")
+    }
+}

codeGenCpu6502/codeGenCpu6502.iml

@@ -0,0 +1,20 @@
+<?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="inheritedJdk" />
+    <orderEntry type="sourceFolder" forTests="false" />
+    <orderEntry type="library" name="KotlinJavaRuntime" level="project" />
+    <orderEntry type="module" module-name="codeCore" />
+    <orderEntry type="module" module-name="simpleAst" />
+    <orderEntry type="library" name="michael.bull.kotlin.result.jvm" level="project" />
+    <orderEntry type="library" name="io.kotest.assertions.core.jvm" level="project" />
+    <orderEntry type="library" name="io.kotest.runner.junit5.jvm" level="project" />
+    <orderEntry type="library" name="io.kotest.framework.datatest" level="project" />
+  </component>
+</module>

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

@@ -0,0 +1,769 @@
+package prog8.codegen.cpu6502
+
+import prog8.code.GENERATED_LABEL_PREFIX
+import prog8.code.StConstant
+import prog8.code.StMemVar
+import prog8.code.SymbolTable
+import prog8.code.core.ICompilationTarget
+
+
+// note: see https://wiki.nesdev.org/w/index.php/6502_assembly_optimisations
+
+
+internal fun optimizeAssembly(lines: MutableList<String>, machine: ICompilationTarget, symbolTable: SymbolTable): Int {
+
+    var numberOfOptimizations = 0
+
+    var linesByFour = getLinesBy(lines, 4)
+
+    var mods = optimizeIncDec(linesByFour)
+    if(mods.isNotEmpty()) {
+        apply(mods, lines)
+        linesByFour = getLinesBy(lines, 4)
+        numberOfOptimizations++
+    }
+
+    mods = optimizeStoreLoadSame(linesByFour, machine, symbolTable)
+    if(mods.isNotEmpty()) {
+        apply(mods, lines)
+        linesByFour = getLinesBy(lines, 4)
+        numberOfOptimizations++
+    }
+
+    mods = optimizeJsrRtsAndOtherCombinations(linesByFour)
+    if(mods.isNotEmpty()) {
+        apply(mods, lines)
+        linesByFour = getLinesBy(lines, 4)
+        numberOfOptimizations++
+    }
+
+    mods = optimizeUselessPushPopStack(linesByFour)
+    if(mods.isNotEmpty()) {
+        apply(mods, lines)
+        linesByFour = getLinesBy(lines, 4)
+        numberOfOptimizations++
+    }
+
+    mods = optimizeUnneededTempvarInAdd(linesByFour)
+    if(mods.isNotEmpty()) {
+        apply(mods, lines)
+        linesByFour = getLinesBy(lines, 4)
+        numberOfOptimizations++
+    }
+
+    mods = optimizeTSBtoRegularOr(linesByFour)
+    if(mods.isNotEmpty()) {
+        apply(mods, lines)
+        linesByFour = getLinesBy(lines, 4)
+        numberOfOptimizations++
+    }
+
+    var linesByFourteen = getLinesBy(lines, 14)
+    mods = optimizeSameAssignments(linesByFourteen, machine, symbolTable)
+    if(mods.isNotEmpty()) {
+        apply(mods, lines)
+        linesByFourteen = getLinesBy(lines, 14)
+        numberOfOptimizations++
+    }
+
+    mods = optimizeSamePointerIndexingAndUselessBeq(linesByFourteen)
+    if(mods.isNotEmpty()) {
+        apply(mods, lines)
+        linesByFourteen = getLinesBy(lines, 14)
+        numberOfOptimizations++
+    }
+
+    return numberOfOptimizations
+}
+
+private fun String.isBranch() = this.startsWith("b")
+private fun String.isStoreReg() = this.startsWith("sta") || this.startsWith("sty") || this.startsWith("stx")
+private fun String.isStoreRegOrZero() = this.isStoreReg() || this.startsWith("stz")
+private fun String.isLoadReg() = this.startsWith("lda") || this.startsWith("ldy") || this.startsWith("ldx")
+
+private class Modification(val lineIndex: Int, val remove: Boolean, val replacement: String?, val removeLabel: Boolean=false)
+
+private fun apply(modifications: List<Modification>, lines: MutableList<String>) {
+    for (modification in modifications.sortedBy { it.lineIndex }.reversed()) {
+        if(modification.remove) {
+            if(modification.removeLabel)
+                lines.removeAt(modification.lineIndex)
+            else {
+                val line = lines[modification.lineIndex]
+                if (line.length < 2 || line[0] == ';' || line.trimStart()[0] == ';')
+                    lines.removeAt(modification.lineIndex)
+                else if (haslabel(line)) {
+                    val label = keeplabel(line)
+                    if (label.isNotEmpty())
+                        lines[modification.lineIndex] = label
+                    else
+                        lines.removeAt(modification.lineIndex)
+                } else lines.removeAt(modification.lineIndex)
+            }
+        }
+        else
+            lines[modification.lineIndex] = modification.replacement!!
+    }
+}
+
+private fun haslabel(line: String): Boolean {
+    return line.length>1 && line[0]!=';' && (!line[0].isWhitespace() || ':' in line)
+}
+
+private fun keeplabel(line: String): String {
+    if(':' in line)
+        return line.substringBefore(':') + ':'
+    val splits = line.split('\t', ' ', limit=2)
+    return if(splits.size>1) splits[0] + ':' else ""
+}
+
+private fun getLinesBy(lines: MutableList<String>, windowSize: Int) =
+// all lines (that aren't empty or comments) in sliding windows of certain size
+        lines.asSequence().withIndex().filter { it.value.isNotBlank() && !it.value.trimStart().startsWith(';') }.windowed(windowSize, partialWindows = false)
+
+private fun optimizeSameAssignments(
+    linesByFourteen: Sequence<List<IndexedValue<String>>>,
+    machine: ICompilationTarget,
+    symbolTable: SymbolTable
+): List<Modification> {
+
+    // Optimize sequential assignments of the same value to various targets (bytes, words, floats)
+    // the float one is the one that requires 2*7=14 lines of code to check...
+    // The better place to do this is in the Compiler instead and never create these types of assembly, but hey
+
+    val mods = mutableListOf<Modification>()
+    for (lines in linesByFourteen) {
+        val first = lines[0].value.trimStart()
+        val second = lines[1].value.trimStart()
+        val third = lines[2].value.trimStart()
+        val fourth = lines[3].value.trimStart()
+        val fifth = lines[4].value.trimStart()
+        val sixth = lines[5].value.trimStart()
+        val seventh = lines[6].value.trimStart()
+        val eighth = lines[7].value.trimStart()
+
+        if(first.startsWith("lda") && second.startsWith("ldy") && third.startsWith("sta") && fourth.startsWith("sty") &&
+                fifth.startsWith("lda") && sixth.startsWith("ldy") && seventh.startsWith("sta") && eighth.startsWith("sty")) {
+            val firstvalue = first.substring(4)
+            val secondvalue = second.substring(4)
+            val thirdvalue = fifth.substring(4)
+            val fourthvalue = sixth.substring(4)
+            if(firstvalue==thirdvalue && secondvalue==fourthvalue) {
+                // lda/ldy   sta/sty   twice the same word -->  remove second lda/ldy pair (fifth and sixth lines)
+                val address1 = getAddressArg(first, symbolTable)
+                val address2 = getAddressArg(second, symbolTable)
+                if(address1==null || address2==null || (!machine.isIOAddress(address1) && !machine.isIOAddress(address2))) {
+                    mods.add(Modification(lines[4].index, true, null))
+                    mods.add(Modification(lines[5].index, true, null))
+                }
+            }
+        }
+
+        if(first.startsWith("lda") && second.startsWith("sta") && third.startsWith("lda") && fourth.startsWith("sta")) {
+            val firstvalue = first.substring(4)
+            val secondvalue = third.substring(4)
+            if(firstvalue==secondvalue) {
+                // lda value / sta ? / lda same-value / sta ?  -> remove second lda (third line)
+                val address = getAddressArg(first, symbolTable)
+                if(address==null || !machine.isIOAddress(address))
+                    mods.add(Modification(lines[2].index, true, null))
+            }
+        }
+
+        if(first.startsWith("lda") && second.startsWith("ldy") && third.startsWith("sta") && fourth.startsWith("sty") &&
+                fifth.startsWith("lda") && sixth.startsWith("ldy") &&
+                (seventh.startsWith("jsr  floats.copy_float") || seventh.startsWith("jsr  cx16flt.copy_float"))) {
+
+            val nineth = lines[8].value.trimStart()
+            val tenth = lines[9].value.trimStart()
+            val eleventh = lines[10].value.trimStart()
+            val twelveth = lines[11].value.trimStart()
+            val thirteenth = lines[12].value.trimStart()
+            val fourteenth = lines[13].value.trimStart()
+
+            if(eighth.startsWith("lda") && nineth.startsWith("ldy") && tenth.startsWith("sta") && eleventh.startsWith("sty") &&
+                    twelveth.startsWith("lda") && thirteenth.startsWith("ldy") &&
+                    (fourteenth.startsWith("jsr  floats.copy_float") || fourteenth.startsWith("jsr  cx16flt.copy_float"))) {
+
+                if(first.substring(4) == eighth.substring(4) && second.substring(4)==nineth.substring(4)) {
+                    // identical float init
+                    mods.add(Modification(lines[7].index, true, null))
+                    mods.add(Modification(lines[8].index, true, null))
+                    mods.add(Modification(lines[9].index, true, null))
+                    mods.add(Modification(lines[10].index, true, null))
+                }
+            }
+        }
+
+        var overlappingMods = false
+        /*
+        sta  prog8_lib.retval_intermX      ; remove
+        sty  prog8_lib.retval_intermY      ; remove
+        lda  prog8_lib.retval_intermX      ; remove
+        ldy  prog8_lib.retval_intermY      ; remove
+        sta  A1
+        sty  A2
+         */
+        if(first.isStoreReg() && second.isStoreReg()
+            && third.isLoadReg() && fourth.isLoadReg()
+            && fifth.isStoreReg() && sixth.isStoreReg()) {
+            val reg1 = first[2]
+            val reg2 = second[2]
+            val reg3 = third[2]
+            val reg4 = fourth[2]
+            val reg5 = fifth[2]
+            val reg6 = sixth[2]
+            if (reg1 == reg3 && reg1 == reg5 && reg2 == reg4 && reg2 == reg6) {
+                val firstvalue = first.substring(4)
+                val secondvalue = second.substring(4)
+                val thirdvalue = third.substring(4)
+                val fourthvalue = fourth.substring(4)
+                if(firstvalue.contains("prog8_lib.retval_interm") && secondvalue.contains("prog8_lib.retval_interm")
+                    && firstvalue==thirdvalue && secondvalue==fourthvalue) {
+                    mods.add(Modification(lines[0].index, true, null))
+                    mods.add(Modification(lines[1].index, true, null))
+                    mods.add(Modification(lines[2].index, true, null))
+                    mods.add(Modification(lines[3].index, true, null))
+                    overlappingMods = true
+                }
+            }
+        }
+
+        /*
+        sta  A1
+        sty  A2
+        lda  A1     ; can be removed
+        ldy  A2     ; can be removed if not followed by a branch instuction
+         */
+        if(!overlappingMods && first.isStoreReg() && second.isStoreReg()
+            && third.isLoadReg() && fourth.isLoadReg()) {
+            val reg1 = first[2]
+            val reg2 = second[2]
+            val reg3 = third[2]
+            val reg4 = fourth[2]
+            if(reg1==reg3 && reg2==reg4) {
+                val firstvalue = first.substring(4)
+                val secondvalue = second.substring(4)
+                val thirdvalue = third.substring(4)
+                val fourthvalue = fourth.substring(4)
+                if(firstvalue==thirdvalue && secondvalue == fourthvalue) {
+                    val address = getAddressArg(first, symbolTable)
+                    if(address==null || !machine.isIOAddress(address)) {
+                        overlappingMods = true
+                        mods.add(Modification(lines[2].index, true, null))
+                        if (!fifth.startsWith('b'))
+                            mods.add(Modification(lines[3].index, true, null))
+                    }
+                }
+            }
+        }
+
+        /*
+        sta  A1
+        sty  A2     ; ... or stz
+        lda  A1     ; can be removed if not followed by a branch instruction
+         */
+        if(!overlappingMods && first.isStoreReg() && second.isStoreRegOrZero()
+            && third.isLoadReg() && !fourth.isBranch()) {
+            val reg1 = first[2]
+            val reg3 = third[2]
+            if(reg1==reg3) {
+                val firstvalue = first.substring(4)
+                val thirdvalue = third.substring(4)
+                if(firstvalue==thirdvalue) {
+                    val address = getAddressArg(first, symbolTable)
+                    if(address==null || !machine.isIOAddress(address)) {
+                        overlappingMods = true
+                        mods.add(Modification(lines[2].index, true, null))
+                    }
+                }
+            }
+        }
+
+        /*
+        sta  A1
+        ldy  A1     ; make tay
+        sta  A1     ; remove
+         */
+        if(!overlappingMods && first.startsWith("sta") && second.isLoadReg()
+            && third.startsWith("sta") && second.length>4) {
+            val firstvalue = first.substring(4)
+            val secondvalue = second.substring(4)
+            val thirdvalue = third.substring(4)
+            if(firstvalue==secondvalue && firstvalue==thirdvalue) {
+                val address = getAddressArg(first, symbolTable)
+                if(address==null || !machine.isIOAddress(address)) {
+                    overlappingMods = true
+                    val reg2 = second[2]
+                    mods.add(Modification(lines[1].index, false, "  ta$reg2"))
+                    mods.add(Modification(lines[2].index, true, null))
+                }
+            }
+        }
+
+        /*
+        sta  A   ; or stz     double store, remove this first one
+        sta  A   ; or stz
+        However, this cannot be done relyably because 'A' could be a constant symbol referring to an I/O address.
+        We can't see that here and would otherwise delete valid double stores.
+        */
+    }
+
+    return mods
+}
+
+private fun optimizeSamePointerIndexingAndUselessBeq(linesByFourteen: Sequence<List<IndexedValue<String>>>): List<Modification> {
+
+    // Optimize same pointer indexing where for instance we load and store to the same ptr index in Y
+    // if Y isn't modified in between we can omit the second LDY:
+    //    ldy  #0
+    //    lda  (ptr),y
+    //    ora  #3       ; <-- instruction(s) that don't modify Y
+    //    ldy  #0       ; <-- can be removed
+    //    sta  (ptr),y
+
+    val mods = mutableListOf<Modification>()
+    for (lines in linesByFourteen) {
+        val first = lines[0].value.trimStart()
+        val second = lines[1].value.trimStart()
+        val third = lines[2].value.trimStart()
+        val fourth = lines[3].value.trimStart()
+        val fifth = lines[4].value.trimStart()
+        val sixth = lines[5].value.trimStart()
+
+        if(first.startsWith("ldy") && second.startsWith("lda") && fourth.startsWith("ldy") && fifth.startsWith("sta")) {
+            val firstvalue = first.substring(4)
+            val secondvalue = second.substring(4)
+            val fourthvalue = fourth.substring(4)
+            val fifthvalue = fifth.substring(4)
+            if("y" !in third && firstvalue==fourthvalue && secondvalue==fifthvalue && secondvalue.endsWith(",y") && fifthvalue.endsWith(",y")) {
+                mods.add(Modification(lines[3].index, true, null))
+            }
+        }
+        if(first.startsWith("ldy") && second.startsWith("lda") && fifth.startsWith("ldy") && sixth.startsWith("sta")) {
+            val firstvalue = first.substring(4)
+            val secondvalue = second.substring(4)
+            val fifthvalue = fifth.substring(4)
+            val sixthvalue = sixth.substring(4)
+            if("y" !in third && "y" !in fourth && firstvalue==fifthvalue && secondvalue==sixthvalue && secondvalue.endsWith(",y") && sixthvalue.endsWith(",y")) {
+                mods.add(Modification(lines[4].index, true, null))
+            }
+        }
+
+
+        /*
+    beq  +
+    lda  #1
++
+[ optional:  label_xxxx_shortcut   line here]
+    beq  label_xxxx_shortcut   /  bne label_xxxx_shortcut
+or *_afterif labels.
+
+This gets generated after certain if conditions, and only the branch instruction is needed in these cases.
+         */
+
+        val autoLabelPrefix = GENERATED_LABEL_PREFIX
+        if(first=="beq  +" && second=="lda  #1" && third=="+") {
+            if((fourth.startsWith("beq  $autoLabelPrefix") || fourth.startsWith("bne  $autoLabelPrefix")) &&
+                (fourth.endsWith("_shortcut") || fourth.endsWith("_afterif") || fourth.endsWith("_shortcut:") || fourth.endsWith("_afterif:"))) {
+                mods.add(Modification(lines[0].index, true, null))
+                mods.add(Modification(lines[1].index, true, null))
+                mods.add(Modification(lines[2].index, true, null))
+            }
+            else if(fourth.startsWith(autoLabelPrefix) && (fourth.endsWith("_shortcut") || fourth.endsWith("_shortcut:"))) {
+                if((fifth.startsWith("beq  $autoLabelPrefix") || fifth.startsWith("bne  $autoLabelPrefix")) &&
+                    (fifth.endsWith("_shortcut") || fifth.endsWith("_afterif") || fifth.endsWith("_shortcut:") || fifth.endsWith("_afterif:"))) {
+                    mods.add(Modification(lines[0].index, true, null))
+                    mods.add(Modification(lines[1].index, true, null))
+                    mods.add(Modification(lines[2].index, true, null))
+                }
+            }
+        }
+    }
+
+    return mods
+}
+
+private fun optimizeStoreLoadSame(
+    linesByFour: Sequence<List<IndexedValue<String>>>,
+    machine: ICompilationTarget,
+    symbolTable: SymbolTable
+): List<Modification> {
+    val mods = mutableListOf<Modification>()
+    for (lines in linesByFour) {
+        val first = lines[1].value.trimStart()
+        val second = lines[2].value.trimStart()
+        val third = lines[3].value.trimStart()
+
+        // sta X + lda X,  sty X + ldy X,   stx X + ldx X  -> the second instruction can OFTEN be eliminated
+        if ((first.startsWith("sta ") && second.startsWith("lda ")) ||
+                (first.startsWith("stx ") && second.startsWith("ldx ")) ||
+                (first.startsWith("sty ") && second.startsWith("ldy ")) ||
+                (first.startsWith("lda ") && second.startsWith("lda ")) ||
+                (first.startsWith("ldy ") && second.startsWith("ldy ")) ||
+                (first.startsWith("ldx ") && second.startsWith("ldx "))
+        ) {
+            val attemptRemove =
+                if(third.isBranch()) {
+                    // a branch instruction follows, we can only remove the load instruction if
+                    // another load instruction of the same register precedes the store instruction
+                    // (otherwise wrong cpu flags are used)
+                    val loadinstruction = second.substring(0, 3)
+                    lines[0].value.trimStart().startsWith(loadinstruction)
+                }
+                else {
+                    // no branch instruction follows, we can remove the load instruction
+                    val address = getAddressArg(lines[2].value, symbolTable)
+                    address==null || !machine.isIOAddress(address)
+                }
+
+            if(attemptRemove) {
+                val firstLoc = first.substring(4).trimStart()
+                val secondLoc = second.substring(4).trimStart()
+                if (firstLoc == secondLoc)
+                    mods.add(Modification(lines[2].index, true, null))
+            }
+        }
+        else if(first=="pha" && second=="pla" ||
+            first=="phx" && second=="plx" ||
+            first=="phy" && second=="ply" ||
+            first=="php" && second=="plp") {
+            mods.add(Modification(lines[1].index, true, null))
+            mods.add(Modification(lines[2].index, true, null))
+        } else if(first=="pha" && second=="plx") {
+            mods.add(Modification(lines[1].index, true, null))
+            mods.add(Modification(lines[2].index, false, "  tax"))
+        } else if(first=="pha" && second=="ply") {
+            mods.add(Modification(lines[1].index, true, null))
+            mods.add(Modification(lines[2].index, false, "  tay"))
+        } else if(first=="phx" && second=="pla") {
+            mods.add(Modification(lines[1].index, true, null))
+            mods.add(Modification(lines[2].index, false, "  txa"))
+        } else if(first=="phy" && second=="pla") {
+            mods.add(Modification(lines[1].index, true, null))
+            mods.add(Modification(lines[2].index, false, "  tya"))
+        }
+
+
+        // lda X + sta X,  ldy X + sty X,   ldx X + stx X  -> the second instruction can be eliminated
+        if ((first.startsWith("lda ") && second.startsWith("sta ")) ||
+            (first.startsWith("ldx ") && second.startsWith("stx ")) ||
+            (first.startsWith("ldy ") && second.startsWith("sty "))
+        ) {
+            val firstLoc = first.substring(4).trimStart()
+            val secondLoc = second.substring(4).trimStart()
+            if (firstLoc == secondLoc)
+                mods.add(Modification(lines[2].index, true, null))
+        }
+    }
+    return mods
+}
+
+private val identifierRegex = Regex("""^([a-zA-Z_$][a-zA-Z\d_.$]*)""")
+
+private fun getAddressArg(line: String, symbolTable: SymbolTable): UInt? {
+    // try to get the constant value address, could return null if it's a symbol instead
+    val loadArg = line.trimStart().substring(3).trim()
+    return when {
+        loadArg.startsWith('$') -> loadArg.substring(1).toUIntOrNull(16)
+        loadArg.startsWith('%') -> loadArg.substring(1).toUIntOrNull(2)
+        loadArg.startsWith('#') -> null
+        loadArg.startsWith('(') -> null
+        loadArg[0].isLetter() -> {
+            val identMatch = identifierRegex.find(loadArg)
+            if(identMatch!=null) {
+                val identifier = identMatch.value
+                when (val symbol = symbolTable.flat[identifier]) {
+                    is StConstant -> symbol.value.toUInt()
+                    is StMemVar -> symbol.address
+                    else -> null
+                }
+            } else null
+        }
+        else -> loadArg.substring(1).toUIntOrNull()
+    }
+}
+
+private fun optimizeIncDec(linesByFour: Sequence<List<IndexedValue<String>>>): List<Modification> {
+    // sometimes, iny+dey / inx+dex / dey+iny / dex+inx sequences are generated, these can be eliminated.
+    val mods = mutableListOf<Modification>()
+    for (lines in linesByFour) {
+        val first = lines[0].value
+        val second = lines[1].value
+        if ((" iny" in first || "\tiny" in first) && (" dey" in second || "\tdey" in second)
+                || (" inx" in first || "\tinx" in first) && (" dex" in second || "\tdex" in second)
+                || (" ina" in first || "\tina" in first) && (" dea" in second || "\tdea" in second)
+                || (" inc  a" in first || "\tinc  a" in first) && (" dec  a" in second || "\tdec  a" in second)
+                || (" dey" in first || "\tdey" in first) && (" iny" in second || "\tiny" in second)
+                || (" dex" in first || "\tdex" in first) && (" inx" in second || "\tinx" in second)
+                || (" dea" in first || "\tdea" in first) && (" ina" in second || "\tina" in second)
+                || (" dec  a" in first || "\tdec  a" in first) && (" inc  a" in second || "\tinc  a" in second)) {
+            mods.add(Modification(lines[0].index, true, null))
+            mods.add(Modification(lines[1].index, true, null))
+        }
+
+    }
+    return mods
+}
+
+private fun optimizeJsrRtsAndOtherCombinations(linesByFour: Sequence<List<IndexedValue<String>>>): List<Modification> {
+    // jsr Sub + rts -> jmp Sub
+    // jmp Sub + rts -> jmp Sub
+    // rts + jmp -> remove jmp
+    // rts + bxx -> remove bxx
+    // lda  + cmp #0 -> remove cmp,  same for cpy and cpx.
+    // bra/jmp + bra/jmp -> remove second bra/jmp   (bra bra / jmp jmp are not removed because this is likely a jump table!)
+    // and some other optimizations.
+
+    val mods = mutableListOf<Modification>()
+    for (lines in linesByFour) {
+        val first = lines[0].value
+        val second = lines[1].value
+        val third = lines[2].value
+
+        if(!haslabel(second)) {
+            if ((" jmp" in first || "\tjmp" in first ) && (" rts" in second || "\trts" in second)) {
+                mods += Modification(lines[1].index, true, null)
+            }
+            else if ((" jsr" in first || "\tjsr" in first ) && (" rts" in second || "\trts" in second)) {
+                if("floats.pushFAC" !in first && "floats.popFAC" !in first) {       // these 2 routines depend on being called with JSR!!
+                    mods += Modification(lines[0].index, false, lines[0].value.replace("jsr", "jmp"))
+                    mods += Modification(lines[1].index, true, null)
+                }
+            }
+            else if (" rts" in first || "\trts" in first) {
+                if (" jmp" in second || "\tjmp" in second)
+                    mods += Modification(lines[1].index, true, null)
+                else if (" bra" in second || "\tbra" in second)
+                    mods += Modification(lines[1].index, true, null)
+                else if (" bcc" in second || "\tbcc" in second)
+                    mods += Modification(lines[1].index, true, null)
+                else if (" bcs" in second || "\tbcs" in second)
+                    mods += Modification(lines[1].index, true, null)
+                else if (" beq" in second || "\tbeq" in second)
+                    mods += Modification(lines[1].index, true, null)
+                else if (" bne" in second || "\tbne" in second)
+                    mods += Modification(lines[1].index, true, null)
+                else if (" bmi" in second || "\tbmi" in second)
+                    mods += Modification(lines[1].index, true, null)
+                else if (" bpl" in second || "\tbpl" in second)
+                    mods += Modification(lines[1].index, true, null)
+                else if (" bvs" in second || "\tbvs" in second)
+                    mods += Modification(lines[1].index, true, null)
+                else if (" bvc" in second || "\tbvc" in second)
+                    mods += Modification(lines[1].index, true, null)
+            }
+
+            if ((" lda" in first || "\tlda" in first) && (" cmp  #0" in second || "\tcmp  #0" in second) ||
+                (" ldx" in first || "\tldx" in first) && (" cpx  #0" in second || "\tcpx  #0" in second) ||
+                (" ldy" in first || "\tldy" in first) && (" cpy  #0" in second || "\tcpy  #0" in second)
+            ) {
+                mods.add(Modification(lines[1].index, true, null))
+            }
+            else if(" cmp  #0" in second || "\tcmp  #0" in second) {
+                // there are many instructions that modify A and set the bits...
+                for(instr in arrayOf("lda", "ora", "and", "eor", "adc", "sbc", "asl", "cmp", "inc  a", "lsr", "pla", "rol", "ror", "txa", "tya")) {
+                    if(" $instr" in first || "\t$instr" in first) {
+                        mods.add(Modification(lines[1].index, true, null))
+                    }
+                }
+            }
+
+            // only remove bra followed by jmp or jmp followed by bra
+            // bra bra or jmp jmp is likely part of a jump table, which should keep all entries!
+            if((" bra" in first || "\tbra" in first) && (" jmp" in second || "\tjmp" in second)) {
+                mods.add(Modification(lines[1].index, true, null))
+            }
+            if((" jmp" in first || "\tjmp" in first) && (" bra" in second || "\tbra" in second)) {
+                mods.add(Modification(lines[1].index, true, null))
+            }
+        }
+
+        /*
+    LDA NUM1
+    CMP NUM2
+    BCC LABEL
+    BEQ LABEL
+
+(or something similar) which branches to LABEL when NUM1 <= NUM2. (In this case NUM1 and NUM2 are unsigned numbers.) However, consider the following sequence:
+
+    LDA NUM2
+    CMP NUM1
+    BCS LABEL
+         */
+        val tfirst = first.trimStart()
+        val tsecond = second.trimStart()
+        val tthird = lines[2].value.trimStart()
+        val tfourth = lines[3].value.trimStart()
+        if(tfirst.startsWith("lda") && tsecond.startsWith("cmp") && tthird.startsWith("bcc") && tfourth.startsWith("beq")) {
+            val label = tthird.substring(4)
+            if(label==tfourth.substring(4)) {
+                mods += Modification(lines[0].index, false, "  lda  ${tsecond.substring(4)}")
+                mods += Modification(lines[1].index, false, "  cmp  ${tfirst.substring(4)}")
+                mods += Modification(lines[2].index, false, "  bcs  $label")
+                mods += Modification(lines[3].index, true, null)
+            }
+        }
+
+
+        fun sameLabel(branchInstr: String, jumpInstr: String, labelInstr: String): Boolean {
+            if('(' in jumpInstr) return false       // indirect jump cannot be replaced
+            val label = labelInstr.trimEnd().substringBefore(':').substringBefore(' ').substringBefore('\t')
+            val branchLabel = branchInstr.trimStart().substring(3).trim()
+            return label==branchLabel
+        }
+
+        // beq Label + jmp Addr + Label  -> bne Addr
+        if((" jmp" in second || "\tjmp " in second) && haslabel(third)) {
+            if((" beq " in first || "\tbeq " in first) && sameLabel(first, second, third)) {
+                val branch = second.replace("jmp", "bne")
+                mods.add(Modification(lines[0].index, true, null))
+                mods.add(Modification(lines[1].index, false, branch))
+            }
+            else if((" bne " in first || "\tbne " in first) && sameLabel(first, second, third)) {
+                val branch = second.replace("jmp", "beq")
+                mods.add(Modification(lines[0].index, true, null))
+                mods.add(Modification(lines[1].index, false, branch))
+            }
+            else if((" bcc " in first || "\tbcc " in first) && sameLabel(first, second, third)){
+                val branch = second.replace("jmp", "bcs")
+                mods.add(Modification(lines[0].index, true, null))
+                mods.add(Modification(lines[1].index, false, branch))
+            }
+            else if((" bcs " in first || "\tbcs " in first) && sameLabel(first, second, third)) {
+                val branch = second.replace("jmp", "bcc")
+                mods.add(Modification(lines[0].index, true, null))
+                mods.add(Modification(lines[1].index, false, branch))
+            }
+            else if((" bpl " in first || "\tbpl " in first) && sameLabel(first, second, third)) {
+                val branch = second.replace("jmp", "bmi")
+                mods.add(Modification(lines[0].index, true, null))
+                mods.add(Modification(lines[1].index, false, branch))
+            }
+            else if((" bmi " in first || "\tbmi " in first) && sameLabel(first, second, third)) {
+                val branch = second.replace("jmp", "bpl")
+                mods.add(Modification(lines[0].index, true, null))
+                mods.add(Modification(lines[1].index, false, branch))
+            }
+            else if((" bvc " in first || "\tbvc " in first) && sameLabel(first, second, third)) {
+                val branch = second.replace("jmp", "bvs")
+                mods.add(Modification(lines[0].index, true, null))
+                mods.add(Modification(lines[1].index, false, branch))
+            }
+            else if((" bvs " in first || "\tbvs " in first) && sameLabel(first, second, third)) {
+                val branch = second.replace("jmp", "bvc")
+                mods.add(Modification(lines[0].index, true, null))
+                mods.add(Modification(lines[1].index, false, branch))
+            }
+        }
+    }
+    return mods
+}
+
+private fun optimizeUselessPushPopStack(linesByFour: Sequence<List<IndexedValue<String>>>): List<Modification> {
+    val mods = mutableListOf<Modification>()
+
+    fun optimize(register: Char, lines: List<IndexedValue<String>>) {
+        if(lines[0].value.trimStart().startsWith("ph$register")) {
+            if(lines[2].value.trimStart().startsWith("pl$register")) {
+                val second = lines[1].value.trimStart().take(6).lowercase()
+                if(register!in second
+                    && !second.startsWith("jsr")
+                    && !second.startsWith("pl")
+                    && !second.startsWith("ph")) {
+                    mods.add(Modification(lines[0].index, true, null))
+                    mods.add(Modification(lines[2].index, true, null))
+                }
+            }
+            else if (lines[3].value.trimStart().startsWith("pl$register")) {
+                val second = lines[1].value.trimStart().take(6).lowercase()
+                val third = lines[2].value.trimStart().take(6).lowercase()
+                if(register !in second && register !in third
+                    && !second.startsWith("jsr") && !third.startsWith("jsr")
+                    && !second.startsWith("pl") && !third.startsWith("pl")
+                    && !second.startsWith("ph") && !third.startsWith("ph")) {
+                    mods.add(Modification(lines[0].index, true, null))
+                    mods.add(Modification(lines[3].index, true, null))
+                }
+            }
+        }
+    }
+
+    for (lines in linesByFour) {
+        optimize('a', lines)
+        optimize('x', lines)
+        optimize('y', lines)
+
+        val first = lines[1].value.trimStart()
+        val second = lines[2].value.trimStart()
+        val third = lines[3].value.trimStart()
+
+        // phy + ldy + pla -> tya + ldy
+        // phx + ldx + pla -> txa + ldx
+        // pha + lda + pla -> nop
+        when (first) {
+            "phy" if second.startsWith("ldy ") && third=="pla" -> {
+                mods.add(Modification(lines[3].index, true, null))
+                mods.add(Modification(lines[1].index, false, "  tya"))
+            }
+            "phx" if second.startsWith("ldx ") && third=="pla" -> {
+                mods.add(Modification(lines[3].index, true, null))
+                mods.add(Modification(lines[1].index, false, "  txa"))
+            }
+            "pha" if second.startsWith("lda ") && third=="pla" -> {
+                mods.add(Modification(lines[1].index, true, null))
+                mods.add(Modification(lines[2].index, true, null))
+                mods.add(Modification(lines[3].index, true, null))
+            }
+        }
+    }
+
+
+    return mods
+}
+
+
+private fun optimizeTSBtoRegularOr(linesByFour: Sequence<List<IndexedValue<String>>>): List<Modification> {
+    // Asm peephole:   lda var2 / tsb var1 / lda var1  Replace this with this to save 1 cycle:   lda var1 / ora var2 / sta var1
+    val mods = mutableListOf<Modification>()
+
+    for(lines in linesByFour) {
+        val first = lines[0].value.trimStart()
+        val second = lines[1].value.trimStart()
+        val third = lines[2].value.trimStart()
+        if(first.startsWith("lda") && second.startsWith("tsb") && third.startsWith("lda")) {
+            val operand1 = first.substring(3)
+            val operand2 = second.substring(3)
+            val operand3 = third.substring(3)
+            if(operand1!=operand2 && operand2==operand3) {
+                mods.add(Modification(lines[0].index, false, "  lda  $operand2"))
+                mods.add(Modification(lines[1].index, false, "  ora  $operand1"))
+                mods.add(Modification(lines[2].index, false, "  sta  $operand2"))
+            }
+        }
+    }
+    return mods
+}
+
+private fun optimizeUnneededTempvarInAdd(linesByFour: Sequence<List<IndexedValue<String>>>): List<Modification> {
+    // sequence:  sta  P8ZP_SCRATCH_XX  / lda  something / clc / adc  P8ZP_SCRATCH_XX
+    // this can be performed without the scratch variable:  clc  /  adc  something
+    val mods = mutableListOf<Modification>()
+
+    for(lines in linesByFour) {
+        val first = lines[0].value.trimStart()
+        val second = lines[1].value.trimStart()
+        val third = lines[2].value.trimStart()
+        val fourth = lines[3].value.trimStart()
+        if(first.startsWith("sta  P8ZP_SCRATCH_") && second.startsWith("lda") && third.startsWith("clc") && fourth.startsWith("adc  P8ZP_SCRATCH_") ) {
+            if(fourth.substring(4)==first.substring(4)) {
+                mods.add(Modification(lines[0].index, false, "  clc"))
+                mods.add(Modification(lines[1].index, false, "  adc  ${second.substring(3).trimStart()}"))
+                mods.add(Modification(lines[2].index, true, null))
+                mods.add(Modification(lines[3].index, true, null))
+            }
+        }
+    }
+
+    return mods
+}

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

@@ -0,0 +1,32 @@
+package prog8.codegen.cpu6502
+
+import prog8.code.ast.PtAsmSub
+import prog8.code.core.Cx16VirtualRegisters
+import prog8.code.core.RegisterOrPair
+
+
+fun asmsub6502ArgsEvalOrder(sub: PtAsmSub): List<Int> {
+    val order = mutableListOf<Int>()
+    // order is:
+    //  1) cx16 virtual word registers,
+    //  2) paired CPU registers,
+    //  3) single CPU registers (order Y,X,A),
+    //  4) floating point registers (FAC1, FAC2),
+    //  5) CPU Carry status flag
+    val args = sub.parameters.withIndex()
+    val (cx16regs, args2) = args.partition { it.value.first.registerOrPair in Cx16VirtualRegisters }
+    val pairedRegisters = arrayOf(RegisterOrPair.AX, RegisterOrPair.AY, RegisterOrPair.XY)
+    val (pairedRegs , args3) = args2.partition { it.value.first.registerOrPair in pairedRegisters }
+    val (singleRegsMixed, rest) = args3.partition { it.value.first.registerOrPair != null }
+    val (singleCpuRegs, floatRegs) = singleRegsMixed.partition {it.value.first.registerOrPair != RegisterOrPair.FAC1 && it.value.first.registerOrPair != RegisterOrPair.FAC2  }
+
+    cx16regs.forEach { order += it.index }
+    pairedRegs.forEach { order += it.index }
+    singleCpuRegs.sortedBy { it.value.first.registerOrPair!!.asCpuRegister() }.asReversed().forEach { order += it.index }
+    require(rest.all { it.value.first.registerOrPair==null && it.value.first.statusflag!=null})
+    floatRegs.forEach { order += it.index }
+    rest.forEach { order += it.index }
+    require(order.size==sub.parameters.size)
+
+    return order
+}

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

@@ -0,0 +1,171 @@
+package prog8.codegen.cpu6502
+
+import prog8.code.GENERATED_LABEL_PREFIX
+import prog8.code.IAssemblyProgram
+import prog8.code.core.CompilationOptions
+import prog8.code.core.ICompilationTarget
+import prog8.code.core.IErrorReporter
+import prog8.code.core.OutputType
+import prog8.code.target.C128Target
+import prog8.code.target.C64Target
+import prog8.code.target.PETTarget
+import java.nio.file.Path
+
+
+internal class AssemblyProgram(
+        override val name: String,
+        outputDir: Path,
+        private val compTarget: ICompilationTarget) : IAssemblyProgram {
+
+    private val assemblyFile = outputDir.resolve("$name.asm")
+    private val prgFile = outputDir.resolve("$name.prg")        // CBM prg executable program
+    private val xexFile = outputDir.resolve("$name.xex")        // Atari xex executable program
+    private val binFile = outputDir.resolve("$name.bin")
+    private val viceMonListFile = outputDir.resolve(C64Target.viceMonListName(name))
+    private val listFile = outputDir.resolve("$name.list")
+
+    override fun assemble(options: CompilationOptions, errors: IErrorReporter): Boolean {
+
+        val assemblerCommand: List<String>
+
+        when(options.output) {
+            OutputType.PRG -> {
+                // CBM machines .prg generation.
+
+                val command = mutableListOf("64tass", "--cbm-prg", "--ascii", "--case-sensitive", "--long-branch",
+                    "-Wall", "-Wno-implied-reg", "--no-monitor", "--dump-labels", "--vice-labels", "--labels=$viceMonListFile")
+
+                if(options.warnSymbolShadowing)
+                    command.add("-Wshadow")
+                else
+                    command.add("-Wno-shadow")
+
+                if(options.asmQuiet)
+                    command.add("--quiet")
+
+                if(options.asmListfile) {
+                    command.add("--list=$listFile")
+                }
+
+                command.addAll(listOf("--output", prgFile.toString(), assemblyFile.toString()))
+                assemblerCommand = command
+                if(!options.quiet)
+                    println("\nCreating prg for target ${compTarget.name}.")
+            }
+            OutputType.XEX -> {
+                // Atari800XL .xex generation.
+
+                val command = mutableListOf("64tass", "--atari-xex", "--case-sensitive", "--long-branch",
+                    "-Wall", "-Wno-implied-reg", "--no-monitor", "--dump-labels", "--vice-labels", "--labels=$viceMonListFile")
+
+                if(options.warnSymbolShadowing)
+                    command.add("-Wshadow")
+                else
+                    command.add("-Wno-shadow")
+
+                if(options.asmQuiet)
+                    command.add("--quiet")
+
+                if(options.asmListfile)
+                    command.add("--list=$listFile")
+
+                command.addAll(listOf("--output", xexFile.toString(), assemblyFile.toString()))
+                assemblerCommand = command
+                if(!options.quiet)
+                    println("\nCreating xex for target ${compTarget.name}.")
+            }
+            OutputType.RAW -> {
+                // Neo6502/headerless raw program generation.
+                val command = mutableListOf("64tass", "--nostart", "--case-sensitive", "--long-branch",
+                    "-Wall", "-Wno-implied-reg", "--no-monitor", "--dump-labels", "--vice-labels", "--labels=$viceMonListFile")
+
+                if(options.warnSymbolShadowing)
+                    command.add("-Wshadow")
+                else
+                    command.add("-Wno-shadow")
+
+                if(options.asmQuiet)
+                    command.add("--quiet")
+
+                if(options.asmListfile)
+                    command.add("--list=$listFile")
+
+                command.addAll(listOf("--output", binFile.toString(), assemblyFile.toString()))
+                assemblerCommand = command
+                if(!options.quiet)
+                    println("\nCreating raw binary for target ${compTarget.name}.")
+            }
+            OutputType.LIBRARY -> {
+                // CBM machines library (.bin) generation (with or without 2 byte load address header depending on the compilation target machine)
+
+                val command = mutableListOf("64tass", "--ascii", "--case-sensitive", "--long-branch",
+                    "-Wall", "-Wno-implied-reg", "--no-monitor", "--dump-labels", "--vice-labels", "--labels=$viceMonListFile")
+
+                if(options.warnSymbolShadowing)
+                    command.add("-Wshadow")
+                else
+                    command.add("-Wno-shadow")
+
+                if(options.asmQuiet)
+                    command.add("--quiet")
+
+                if(options.asmListfile)
+                    command.add("--list=$listFile")
+
+                if(compTarget.name in listOf(C64Target.NAME, C128Target.NAME, PETTarget.NAME)) {
+                    if(!options.quiet)
+                        println("\nCreating binary library file with header for target ${compTarget.name}.")
+                    command.add("--cbm-prg")
+                } else {
+                    if(!options.quiet)
+                        println("\nCreating binary library file without header for target ${compTarget.name}.")
+                    command.add("--nostart")       // should be headerless bin, because basic has problems doing a normal LOAD"lib",8,1 - need to use BLOAD
+                }
+
+                command.addAll(listOf("--output", binFile.toString(), assemblyFile.toString()))
+                assemblerCommand = command
+            }
+        }
+
+        if(options.compTarget.additionalAssemblerOptions!=null)
+            assemblerCommand.add(options.compTarget.additionalAssemblerOptions!!)
+
+        val proc = ProcessBuilder(assemblerCommand)
+        if(!options.quiet)
+            proc.inheritIO()
+        val process = proc.start()
+        val result = process.waitFor()
+        if (result == 0) {
+            removeGeneratedLabelsFromMonlist()
+            generateBreakpointList()
+        }
+        return result==0
+    }
+
+    private fun removeGeneratedLabelsFromMonlist() {
+        val pattern = Regex("""al (\w+) \S+$GENERATED_LABEL_PREFIX.+?""")
+        val lines = viceMonListFile.toFile().readLines()
+        viceMonListFile.toFile().outputStream().bufferedWriter().use {
+            for (line in lines) {
+                if(pattern.matchEntire(line)==null)
+                    it.write(line+"\n")
+            }
+        }
+    }
+
+    private fun generateBreakpointList() {
+        // builds list of breakpoints, appends to monitor list file
+        val breakpoints = mutableListOf<String>()
+        val pattern = Regex("""al (\w+) \S+_prog8_breakpoint_\d+.?""")      // gather breakpoints by the source label that's generated for them
+        for (line in viceMonListFile.toFile().readLines()) {
+            val match = pattern.matchEntire(line)
+            if (match != null)
+                breakpoints.add("break $" + match.groupValues[1])
+        }
+        val num = breakpoints.size
+        breakpoints.add(0, "; breakpoint list now follows")
+        breakpoints.add(1, "; $num breakpoints have been defined")
+        breakpoints.add(2, "del")
+        viceMonListFile.toFile().appendText(breakpoints.joinToString("\n") + "\n")
+    }
+}

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

@@ -0,0 +1,935 @@
+package prog8.codegen.cpu6502
+
+import com.github.michaelbull.result.fold
+import prog8.code.StMemVar
+import prog8.code.StStaticVariable
+import prog8.code.ast.PtForLoop
+import prog8.code.ast.PtIdentifier
+import prog8.code.ast.PtRange
+import prog8.code.core.*
+import kotlin.math.absoluteValue
+
+internal class ForLoopsAsmGen(
+    private val asmgen: AsmGen6502Internal,
+    private val zeropage: Zeropage
+) {
+
+    internal fun translate(stmt: PtForLoop) {
+        val iterableDt = stmt.iterable.type
+        when(stmt.iterable) {
+            is PtRange -> {
+                val range = (stmt.iterable as PtRange).toConstantIntegerRange()
+                if(range==null) {
+                    translateForOverNonconstRange(stmt, iterableDt, stmt.iterable as PtRange)
+                } else {
+                    translateForOverConstRange(stmt, iterableDt, range)
+                }
+            }
+            is PtIdentifier -> {
+                translateForOverIterableVar(stmt, iterableDt, stmt.iterable as PtIdentifier)
+            }
+            else -> throw AssemblyError("can't iterate over ${stmt.iterable.javaClass} - should have been replaced by a variable")
+        }
+    }
+
+    private fun translateForOverNonconstRange(stmt: PtForLoop, iterableDt: DataType, range: PtRange) {
+        if(range.step.asConstInteger()!! < -1) {
+            val limit = range.to.asConstInteger()
+            if(limit==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.isByteArray -> forOverNonconstByteRange(stmt, iterableDt, range)
+            iterableDt.isWordArray && !iterableDt.isSplitWordArray -> forOverNonconstWordRange(stmt, iterableDt, range)
+            else -> throw AssemblyError("range expression can only be byte or word")
+        }
+
+        asmgen.loopEndLabels.removeLast()
+    }
+
+    private fun forOverNonconstByteRange(stmt: PtForLoop, iterableDt: DataType, range: PtRange) {
+        val stepsize = range.step.asConstInteger()!!
+        val loopLabel = asmgen.makeLabel("for_loop")
+        val endLabel = asmgen.makeLabel("for_end")
+        asmgen.loopEndLabels.add(endLabel)
+        val varname = asmgen.asmVariableName(stmt.variable)
+
+        asmgen.assignExpressionToVariable(range.from, varname, iterableDt.elementType())
+        when (stepsize) {
+            -1 if range.to.asConstInteger()==0 -> {
+                // simple loop downto 0 step -1
+                asmgen.out(loopLabel)
+                asmgen.translate(stmt.statements)
+                asmgen.out("""
+                    dec  $varname
+                    lda  $varname
+                    cmp  #255
+                    bne  $loopLabel""")
+            }
+            -1 if range.to.asConstInteger()==1 -> {
+                // simple loop downto 1 step -1
+                asmgen.out(loopLabel)
+                asmgen.translate(stmt.statements)
+                asmgen.out("""
+                    dec  $varname
+                    bne  $loopLabel""")
+            }
+            1, -1 -> forOverBytesRangeStepOne(range, varname, iterableDt, loopLabel, endLabel, stmt)
+            else -> forOverBytesRangeStepGreaterOne(range, varname, iterableDt, loopLabel, endLabel, stmt)
+        }
+    }
+
+    private fun forOverBytesRangeStepOne(range: PtRange, varname: String, iterableDt: DataType, loopLabel: String, endLabel: String, forloop: PtForLoop) {
+        // bytes range, step 1 or -1
+
+        val stepsize = range.step.asConstInteger()!!
+        val incdec = if(stepsize==1) "inc" else "dec"
+
+        if(asmgen.options.romable) {
+            // cannot use self-modifying code, cannot use cpu stack (because loop can be interrupted halfway)
+            // so we need to store the loop end value in a newly allocated temporary variable
+            val toValueVar = asmgen.createTempVarReused(iterableDt.elementType().base, false, range)
+            asmgen.assignExpressionToRegister(range.to, RegisterOrPair.A)
+            asmgen.out("  sta  $toValueVar")
+            // pre-check for end already reached
+            if(iterableDt.isSignedByteArray) {
+                if(stepsize<0) {
+                    asmgen.out("""
+                        clc
+                        sbc  $varname
+                        bvc  +
+                        eor  #$80
++                       bpl  $endLabel""")
+                }
+                else {
+                    asmgen.out("""
+                        sec
+                        sbc  $varname
+                        bvc  +
+                        eor  #$80
++                       bmi  $endLabel""")
+                }
+            } else {
+                if(stepsize<0) {
+                    asmgen.out("""
+                        cmp  $varname
+                        beq  +
+                        bcs  $endLabel
++""")
+                }
+                else {
+                    asmgen.out("  cmp  $varname  |  bcc  $endLabel")
+                }
+            }
+            asmgen.out(loopLabel)
+            asmgen.translate(forloop.statements)
+            asmgen.out("""
+                lda  $varname
+                cmp  $toValueVar
+                beq  $endLabel
+                $incdec  $varname""")
+            asmgen.jmp(loopLabel)
+            asmgen.out(endLabel)
+
+        } else {
+
+            // use self-modifying code to store the loop end comparison value
+            val modifiedLabel = asmgen.makeLabel("for_modified")
+            asmgen.assignExpressionToRegister(range.to, RegisterOrPair.A)
+            // pre-check for end already reached
+            if(iterableDt.isSignedByteArray) {
+                asmgen.out("  sta  $modifiedLabel+1")
+                if(stepsize<0) {
+                    asmgen.out("""
+                        clc
+                        sbc  $varname
+                        bvc  +
+                        eor  #$80
++                       bpl  $endLabel""")
+                }
+                else
+                    asmgen.out("""
+                        sec
+                        sbc  $varname
+                        bvc  +
+                        eor  #$80
++                       bmi  $endLabel""")
+            } else {
+                if(stepsize<0) {
+                    asmgen.out("""
+                        cmp  $varname
+                        beq  +
+                        bcs  $endLabel
++""")
+                }
+                else {
+                    asmgen.out("  cmp  $varname  |  bcc  $endLabel")
+                }
+                asmgen.out("  sta  $modifiedLabel+1")
+            }
+            asmgen.out(loopLabel)
+            asmgen.translate(forloop.statements)
+            asmgen.out("""
+                lda  $varname
+$modifiedLabel  cmp  #0         ; modified 
+                beq  $endLabel
+                $incdec  $varname""")
+            asmgen.jmp(loopLabel)
+            asmgen.out(endLabel)
+        }
+    }
+
+    private fun forOverBytesRangeStepGreaterOne(range: PtRange, varname: String, iterableDt: DataType, loopLabel: String, endLabel: String, forloop: PtForLoop) {
+        // bytes range, step >= 2 or <= -2
+
+        val stepsize = range.step.asConstInteger()!!
+
+        val modifiedLabel = asmgen.makeLabel("for_modified")
+        asmgen.assignExpressionToRegister(range.to, RegisterOrPair.A)
+        // pre-check for end already reached
+        if(iterableDt.isSignedByteArray) {
+            asmgen.out("  sta  $modifiedLabel+1")
+            if(stepsize<0)
+                asmgen.out("""
+                    clc
+                    sbc  $varname
+                    bvc  +
+                    eor  #$80
++                   bpl  $endLabel""")
+            else
+                asmgen.out("""
+                    sec
+                    sbc  $varname
+                    bvc  +
+                    eor  #$80
++                   bmi  $endLabel""")
+        } else {
+            if(stepsize<0)
+                asmgen.out("""
+                    cmp  $varname
+                    beq  +
+                    bcs  $endLabel
++""")
+            else {
+                asmgen.out("  cmp  $varname  |  bcc  $endLabel")
+            }
+            asmgen.out("  sta  $modifiedLabel+1")
+        }
+        asmgen.out(loopLabel)
+        asmgen.translate(forloop.statements)
+
+        asmgen.romableError("self-modifying code (forloop over bytes range)", forloop.position)  // TODO fix romable; there is self-modifying code below
+        if(stepsize>0) {
+            asmgen.out("""
+                lda  $varname
+                clc
+                adc  #$stepsize
+                sta  $varname
+$modifiedLabel  cmp  #0    ; modified
+                bmi  $loopLabel
+                beq  $loopLabel""")
+        } else {
+            asmgen.out("""
+                lda  $varname
+                sec
+                sbc  #${stepsize.absoluteValue}
+                sta  $varname
+$modifiedLabel  cmp  #0     ; modified
+                bpl  $loopLabel""")
+        }
+        asmgen.out(endLabel)
+    }
+
+    private fun forOverNonconstWordRange(stmt: PtForLoop, iterableDt: DataType, range: PtRange) {
+        val stepsize = range.step.asConstInteger()!!
+        val loopLabel = asmgen.makeLabel("for_loop")
+        val endLabel = asmgen.makeLabel("for_end")
+        asmgen.loopEndLabels.add(endLabel)
+        val varname = asmgen.asmVariableName(stmt.variable)
+        assignLoopvarWord(stmt, range)
+        if(stepsize==-1 && range.to.asConstInteger()==0) {
+            // simple loop downto 0 step -1 (words)
+            asmgen.out(loopLabel)
+            asmgen.translate(stmt.statements)
+            asmgen.out("""
+                lda  $varname
+                bne  ++
+                lda  $varname+1
+                beq  $endLabel
++               lda  $varname
+                bne  +
+                dec  $varname+1
++               dec  $varname""")
+            asmgen.jmp(loopLabel)
+            asmgen.out(endLabel)
+        }
+        else if (stepsize==-1 && range.to.asConstInteger()==1) {
+            // simple loop downto 1 step -1 (words)
+            asmgen.out(loopLabel)
+            asmgen.translate(stmt.statements)
+            asmgen.out("""
+                lda  $varname
+                cmp  #1
+                bne  +
+                lda  $varname+1
+                beq  $endLabel
++               lda  $varname
+                bne  +
+                dec  $varname+1
++               dec  $varname""")
+            asmgen.jmp(loopLabel)
+            asmgen.out(endLabel)
+        }
+        else if (stepsize == 1 || stepsize == -1)
+            forOverWordsRangeStepOne(range, varname, iterableDt, loopLabel, endLabel, stmt)
+        else if (stepsize > 0)
+            forOverWordsRangeStepGreaterOne(range, varname, iterableDt, loopLabel, endLabel, stmt)
+        else
+            forOverWordsRangeStepGreaterOneDescending(range, varname, iterableDt, loopLabel, endLabel, stmt)
+    }
+
+    private fun forOverWordsRangeStepOne(range: PtRange, varname: String, iterableDt: DataType, loopLabel: String, endLabel: String, forloop: PtForLoop) {
+        // words range, step 1 or -1
+        val stepsize = range.step.asConstInteger()!!
+
+        if(asmgen.options.romable) {
+            // cannot use self-modifying code, cannot use cpu stack (because loop can be interrupted halfway)
+            // so we need to store the loop end value in a newly allocated temporary variable
+            val toValueVar = asmgen.createTempVarReused(iterableDt.elementType().base, false, range)
+            asmgen.assignExpressionToRegister(range.to, RegisterOrPair.AY)
+            precheckFromToWord(iterableDt, stepsize, varname, endLabel)
+            asmgen.out("  sta  $toValueVar")
+            asmgen.out("  sty  $toValueVar+1")
+            asmgen.out(loopLabel)
+            asmgen.translate(forloop.statements)
+            asmgen.out("""
+                lda  $varname+1
+                cmp  $toValueVar+1
+                bne  +
+                lda  $varname
+                cmp  $toValueVar
+                beq  $endLabel""")
+            if(stepsize==1) {
+                asmgen.out("""
++                   inc  $varname
+                    bne  $loopLabel
+                    inc  $varname+1""")
+                asmgen.jmp(loopLabel)
+            } else {
+                asmgen.out("""
++                   lda  $varname
+                    bne  +
+                    dec  $varname+1
++                   dec  $varname""")
+                asmgen.jmp(loopLabel)
+            }
+            asmgen.out(endLabel)
+
+        } else {
+
+            val modifiedLabel = asmgen.makeLabel("for_modified")
+            val modifiedLabel2 = asmgen.makeLabel("for_modifiedb")
+            asmgen.assignExpressionToRegister(range.to, RegisterOrPair.AY)
+            precheckFromToWord(iterableDt, stepsize, varname, endLabel)
+            asmgen.out("""
+                sty  $modifiedLabel+1
+                sta  $modifiedLabel2+1
+$loopLabel""")
+            asmgen.translate(forloop.statements)
+            asmgen.out("""
+                lda  $varname+1
+$modifiedLabel  cmp  #0    ; modified 
+                bne  +
+                lda  $varname
+$modifiedLabel2 cmp  #0    ; modified 
+                beq  $endLabel""")
+            if(stepsize==1) {
+                asmgen.out("""
++                   inc  $varname
+                    bne  $loopLabel
+                    inc  $varname+1""")
+                asmgen.jmp(loopLabel)
+            } else {
+                asmgen.out("""
++                   lda  $varname
+                    bne  +
+                    dec  $varname+1
++                   dec  $varname""")
+                asmgen.jmp(loopLabel)
+            }
+            asmgen.out(endLabel)
+        }
+    }
+
+    private fun forOverWordsRangeStepGreaterOne(range: PtRange, varname: String, iterableDt: DataType, loopLabel: String, endLabel: String, stmt: PtForLoop) {
+        // (u)words, step >= 2
+        val stepsize = range.step.asConstInteger()!!
+        val modifiedLabel = asmgen.makeLabel("for_modified")
+        val modifiedLabel2 = asmgen.makeLabel("for_modifiedb")
+        asmgen.assignExpressionToRegister(range.to, RegisterOrPair.AY)
+        precheckFromToWord(iterableDt, stepsize, varname, endLabel)
+        asmgen.out("""
+                sty  $modifiedLabel+1
+                sta  $modifiedLabel2+1
+$loopLabel""")
+        asmgen.translate(stmt.statements)
+
+        asmgen.romableError("self-modifying code (forloop over word range)", stmt.position)  // TODO fix romable; there is self-modifying code below
+        if (iterableDt.isUnsignedWordArray) {
+            asmgen.out("""
+                lda  $varname
+                clc
+                adc  #<$stepsize
+                sta  $varname
+                lda  $varname+1
+                adc  #>$stepsize
+                sta  $varname+1
+$modifiedLabel  cmp  #0     ; modified
+                bcc  $loopLabel
+                bne  $endLabel
+$modifiedLabel2 lda  #0     ; modified
+                cmp  $varname
+                bcc  $endLabel
+                bcs  $loopLabel
+$endLabel""")
+        } else {
+            asmgen.out("""
+                lda  $varname
+                clc
+                adc  #<$stepsize
+                sta  $varname
+                lda  $varname+1
+                adc  #>$stepsize
+                sta  $varname+1
+$modifiedLabel2 lda  #0   ; modified
+                cmp  $varname
+$modifiedLabel  lda  #0   ; modified
+                sbc  $varname+1
+                bvc  +
+                eor  #$80
++               bpl  $loopLabel                
+$endLabel""")
+        }
+    }
+
+    private fun forOverWordsRangeStepGreaterOneDescending(range: PtRange, varname: String, iterableDt: DataType, loopLabel: String, endLabel: String, stmt: PtForLoop) {
+        // (u)words, step <= -2
+        val stepsize = range.step.asConstInteger()!!
+        val modifiedLabel = asmgen.makeLabel("for_modified")
+        val modifiedLabel2 = asmgen.makeLabel("for_modifiedb")
+        asmgen.assignExpressionToRegister(range.to, RegisterOrPair.AY)
+        precheckFromToWord(iterableDt, stepsize, varname, endLabel)
+        asmgen.romableError("self-modifying code (forloop over words range)", stmt.position)  // TODO fix romable; there is self-modifying code below
+        asmgen.out("""
+                sty  $modifiedLabel+1
+                sta  $modifiedLabel2+1
+$loopLabel""")
+        asmgen.translate(stmt.statements)
+        asmgen.out("""
+                lda  $varname
+                sec
+                sbc  #<${stepsize.absoluteValue}
+                sta  $varname
+                tax
+                lda  $varname+1
+                sbc  #>${stepsize.absoluteValue}
+                sta  $varname+1
+                txa
+$modifiedLabel2 cmp  #0    ; modified 
+                lda  $varname+1
+$modifiedLabel  sbc  #0    ; modified
+                bvc  +
+                eor  #$80
++               bpl  $loopLabel                
+$endLabel""")
+    }
+
+    private fun precheckFromToWord(iterableDt: DataType, stepsize: Int, fromVar: String, endLabel: String) {
+        // pre-check for end already reached.
+        // 'to' is in AY, do NOT clobber this!
+        if(iterableDt.isSignedWordArray) {
+            if(stepsize<0)
+                asmgen.out("""
+                    sta  P8ZP_SCRATCH_W2        ; to
+                    sty  P8ZP_SCRATCH_W2+1      ; to
+                    lda  $fromVar
+                    cmp  P8ZP_SCRATCH_W2
+                    lda  $fromVar+1
+                    sbc  P8ZP_SCRATCH_W2+1
+                    bvc  +
+                    eor  #$80
++                   bmi  $endLabel
+                    lda  P8ZP_SCRATCH_W2
+                    ldy  P8ZP_SCRATCH_W2+1""")
+            else
+                asmgen.out("""
+                    sta  P8ZP_SCRATCH_REG
+                    cmp  $fromVar
+                    tya
+                    sbc  $fromVar+1
+                    bvc  +
+                    eor  #$80
++                   bmi  $endLabel
+                    lda  P8ZP_SCRATCH_REG""")
+        } else {
+            if(stepsize<0)
+                asmgen.out("""
+                    cpy  $fromVar+1
+                    beq  +
+                    bcc  ++
+                    bcs  $endLabel
++                   cmp  $fromVar
+                    bcc  +
+                    beq  +
+                    bne  $endLabel
++""")
+            else
+                asmgen.out("""
+                    cpy  $fromVar+1
+                    bcc  $endLabel
+                    bne  +
+                    cmp  $fromVar
+                    bcc  $endLabel
++""")
+        }
+    }
+
+    private fun translateForOverIterableVar(stmt: PtForLoop, iterableDt: DataType, ident: PtIdentifier) {
+        val loopLabel = asmgen.makeLabel("for_loop")
+        val endLabel = asmgen.makeLabel("for_end")
+        asmgen.loopEndLabels.add(endLabel)
+        val iterableName = asmgen.asmVariableName(ident)
+        val numElements = when(val symbol = asmgen.symbolTable.lookup(ident.name)) {
+            is StStaticVariable -> symbol.length!!
+            is StMemVar -> symbol.length!!
+            else -> 0
+        }
+        when {
+            iterableDt.isString -> {
+                if(asmgen.options.romable) {
+                    val indexVar = asmgen.createTempVarReused(BaseDataType.UBYTE, false, stmt)
+                    asmgen.out("""
+                        ldy  #0
+                        sty  $indexVar
+$loopLabel              lda  $iterableName,y
+                        beq  $endLabel
+                        sta  ${asmgen.asmVariableName(stmt.variable)}""")
+                    asmgen.translate(stmt.statements)
+                    asmgen.out("""
+                        inc  $indexVar
+                        ldy  $indexVar
+                        bne  $loopLabel
+$endLabel""")
+                } else {
+                    val indexVar = asmgen.makeLabel("for_index")
+                    asmgen.out("""
+                        ldy  #0
+                        sty  $indexVar
+$loopLabel              lda  $iterableName,y
+                        beq  $endLabel
+                        sta  ${asmgen.asmVariableName(stmt.variable)}""")
+                    asmgen.translate(stmt.statements)
+                    asmgen.out("""
+                        inc  $indexVar
+                        ldy  $indexVar
+                        bne  $loopLabel
+$indexVar   .byte  0                        
+$endLabel""")
+                }
+            }
+            iterableDt.isByteArray || iterableDt.isBoolArray -> {
+                val indexVar = if(asmgen.options.romable)
+                    asmgen.createTempVarReused(iterableDt.elementType().base, false, stmt)
+                else
+                    asmgen.makeLabel("for_index")
+                asmgen.out("""
+                    ldy  #0
+$loopLabel          sty  $indexVar
+                    lda  $iterableName,y
+                    sta  ${asmgen.asmVariableName(stmt.variable)}""")
+                asmgen.translate(stmt.statements)
+                if(numElements<=255) {
+                    asmgen.out("""
+                        ldy  $indexVar
+                        iny
+                        cpy  #$numElements
+                        beq  $endLabel
+                        bne  $loopLabel""")
+                } else {
+                    // length is 256
+                    asmgen.out("""
+                        ldy  $indexVar
+                        iny
+                        bne  $loopLabel
+                        beq  $endLabel""")
+                }
+                if(!asmgen.options.romable) {
+                    if(numElements>=16) {
+                        // allocate index var on ZP if possible, otherwise inline
+                        val result = zeropage.allocate(indexVar, DataType.UBYTE, null, stmt.position, asmgen.errors)
+                        result.fold(
+                            success = { (address, _, _)-> asmgen.out("""$indexVar = $address  ; auto zp UBYTE""") },
+                            failure = { asmgen.out("$indexVar    .byte  0") }
+                        )
+                    } else {
+                        asmgen.out("$indexVar    .byte  0")
+                    }
+                }
+                asmgen.out(endLabel)
+            }
+            iterableDt.isSplitWordArray -> {
+                val indexVar = if(asmgen.options.romable)
+                    asmgen.createTempVarReused(BaseDataType.UBYTE, false, stmt)
+                else
+                    asmgen.makeLabel("for_index")
+                val loopvarName = asmgen.asmVariableName(stmt.variable)
+                asmgen.out("""
+                    ldy  #0
+$loopLabel          sty  $indexVar
+                    lda  ${iterableName}_lsb,y
+                    sta  $loopvarName
+                    lda  ${iterableName}_msb,y
+                    sta  $loopvarName+1""")
+                asmgen.translate(stmt.statements)
+                if(numElements<=255) {
+                    asmgen.out("""
+                        ldy  $indexVar
+                        iny
+                        cpy  #$numElements
+                        beq  $endLabel
+                        bne  $loopLabel""")
+                } else {
+                    // length is 256
+                    asmgen.out("""
+                        ldy  $indexVar
+                        iny
+                        bne  $loopLabel
+                        beq  $endLabel""")
+                }
+                if(!asmgen.options.romable) {
+                    if(numElements>=16) {
+                        // allocate index var on ZP if possible, otherwise inline
+                        val result = zeropage.allocate(indexVar, DataType.UBYTE, null, stmt.position, asmgen.errors)
+                        result.fold(
+                            success = { (address, _, _)-> asmgen.out("""$indexVar = $address  ; auto zp UBYTE""") },
+                            failure = { asmgen.out("$indexVar    .byte  0") }
+                        )
+                    } else {
+                        asmgen.out("$indexVar    .byte  0")
+                    }
+                }
+                asmgen.out(endLabel)
+            }
+            iterableDt.isWordArray -> {
+                val indexVar = if(asmgen.options.romable)
+                    asmgen.createTempVarReused(BaseDataType.UBYTE, false, stmt)
+                else
+                    asmgen.makeLabel("for_index")
+                val loopvarName = asmgen.asmVariableName(stmt.variable)
+                asmgen.out("""
+                    ldy  #0
+$loopLabel          sty  $indexVar
+                    lda  $iterableName,y
+                    sta  $loopvarName
+                    lda  $iterableName+1,y
+                    sta  $loopvarName+1""")
+                asmgen.translate(stmt.statements)
+                if(numElements<=127) {
+                    asmgen.out("""
+                        ldy  $indexVar
+                        iny
+                        iny
+                        cpy  #${numElements*2}
+                        beq  $endLabel
+                        bne  $loopLabel""")
+                } else {
+                    // array size is 128 words, 256 bytes
+                    asmgen.out("""
+                        ldy  $indexVar
+                        iny
+                        iny
+                        bne  $loopLabel
+                        beq  $endLabel""")
+                }
+                if(!asmgen.options.romable) {
+                    if(numElements>=16) {
+                        // allocate index var on ZP if possible, otherwise inline
+                        val result = zeropage.allocate(indexVar, DataType.UBYTE, null, stmt.position, asmgen.errors)
+                        result.fold(
+                            success = { (address, _, _)-> asmgen.out("""$indexVar = $address  ; auto zp UBYTE""") },
+                            failure = { asmgen.out("$indexVar    .byte  0") }
+                        )
+                    } else {
+                        asmgen.out("$indexVar    .byte  0")
+                    }
+                }
+                asmgen.out(endLabel)
+            }
+            iterableDt.isFloatArray -> {
+                throw AssemblyError("for loop with floating point variables is not supported")
+            }
+            else -> throw AssemblyError("can't iterate over $iterableDt")
+        }
+        asmgen.loopEndLabels.removeLast()
+    }
+
+    private fun translateForOverConstRange(stmt: PtForLoop, iterableDt: DataType, range: IntProgression) {
+        if (range.isEmpty() || range.step==0)
+            throw AssemblyError("empty range or step 0")
+        if(iterableDt.isByteArray) {
+            if(range.last==range.first) return translateForSimpleByteRangeAsc(stmt, range)
+            if(range.step==1 && range.last>range.first) return translateForSimpleByteRangeAsc(stmt, range)
+            if(range.step==-1 && range.last<range.first) return translateForSimpleByteRangeDesc(stmt, range, iterableDt.isUnsignedByteArray)
+        }
+        else if(iterableDt.isWordArray) {
+            if(range.last==range.first) return translateForSimpleWordRangeAsc(stmt, range)
+            if(range.step==1 && range.last>range.first) return translateForSimpleWordRangeAsc(stmt, range)
+            if(range.step==-1 && range.last<range.first) return translateForSimpleWordRangeDesc(stmt, range)
+        }
+
+        // not one of the easy cases, generate more complex code...
+        val loopLabel = asmgen.makeLabel("for_loop")
+        val endLabel = asmgen.makeLabel("for_end")
+        asmgen.loopEndLabels.add(endLabel)
+        when {
+            iterableDt.isByteArray -> {
+                // loop over byte range via loopvar, step >= 2 or <= -2
+                val varname = asmgen.asmVariableName(stmt.variable)
+                asmgen.out("""
+                            lda  #${range.first}
+                            sta  $varname
+$loopLabel""")
+                asmgen.translate(stmt.statements)
+                when (range.step) {
+                    0, 1, -1 -> {
+                        throw AssemblyError("step 0, 1 and -1 should have been handled specifically  $range ${stmt.position}")
+                    }
+                    2 -> {
+                        if(range.last==255 || range.last==254) {
+                            asmgen.out("""
+                                inc  $varname
+                                beq  $endLabel
+                                inc  $varname
+                                bne  $loopLabel""")
+                        } else {
+                            asmgen.out("""
+                                inc  $varname
+                                inc  $varname
+                                lda  $varname
+                                cmp  #${range.last+2}
+                                bne  $loopLabel""")
+                        }
+                    }
+                    -2 -> {
+                        when (range.last) {
+                            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""")
+                            else -> asmgen.out("""
+                                    dec  $varname
+                                    dec  $varname
+                                    lda  $varname
+                                    cmp  #${range.last-2}
+                                    bne  $loopLabel""")
+                        }
+                    }
+                    else -> {
+                        // step <= -3 or >= 3
+                        asmgen.out("""
+                            lda  $varname
+                            cmp  #${range.last}
+                            beq  $endLabel
+                            clc
+                            adc  #${range.step}
+                            sta  $varname""")
+                        asmgen.jmp(loopLabel)
+                    }
+                }
+                asmgen.out(endLabel)
+            }
+            iterableDt.isWordArray && !iterableDt.isSplitWordArray -> {
+                // loop over word range via loopvar, step >= 2 or <= -2
+                val varname = asmgen.asmVariableName(stmt.variable)
+                when (range.step) {
+                    0, 1, -1 -> {
+                        throw AssemblyError("step 0, 1 and -1 should have been handled specifically  $stmt")
+                    }
+                    else -> {
+                        // word, step >= 2 or <= -2
+                        // note: range.last has already been adjusted by kotlin itself to actually be the last value of the sequence
+                        asmgen.out("""
+                            lda  #<${range.first}
+                            ldy  #>${range.first}
+                            sta  $varname
+                            sty  $varname+1
+$loopLabel""")
+                        asmgen.translate(stmt.statements)
+                        asmgen.out("""
+                            lda  $varname
+                            cmp  #<${range.last}
+                            bne  +
+                            lda  $varname+1
+                            cmp  #>${range.last}
+                            bne  +
+                            beq  $endLabel
++                           lda  $varname
+                            clc
+                            adc  #<${range.step}
+                            sta  $varname
+                            lda  $varname+1
+                            adc  #>${range.step}
+                            sta  $varname+1""")
+                        asmgen.jmp(loopLabel)
+                        asmgen.out(endLabel)
+                    }
+                }
+            }
+            else -> throw AssemblyError("range expression can only be byte or word")
+        }
+        asmgen.loopEndLabels.removeLast()
+    }
+
+    private fun translateForSimpleByteRangeAsc(stmt: PtForLoop, range: IntProgression) {
+        val loopLabel = asmgen.makeLabel("for_loop")
+        val endLabel = asmgen.makeLabel("for_end")
+        asmgen.loopEndLabels.add(endLabel)
+        val varname = asmgen.asmVariableName(stmt.variable)
+        asmgen.out("""
+                lda  #${range.first}
+                sta  $varname
+$loopLabel""")
+        asmgen.translate(stmt.statements)
+        if (range.last == 255) {
+            asmgen.out("""
+                inc  $varname
+                bne  $loopLabel
+$endLabel""")
+        } else {
+            asmgen.out("""
+                inc  $varname
+                lda  $varname
+                cmp  #${range.last+1}
+                bne  $loopLabel
+$endLabel""")
+        }
+        asmgen.loopEndLabels.removeLast()
+    }
+
+    private fun translateForSimpleByteRangeDesc(stmt: PtForLoop, range: IntProgression, unsigned: Boolean) {
+        val loopLabel = asmgen.makeLabel("for_loop")
+        val varname = asmgen.asmVariableName(stmt.variable)
+        asmgen.out("""
+            lda  #${range.first}
+            sta  $varname
+$loopLabel""")
+        asmgen.translate(stmt.statements)
+        when (range.last) {
+            0 -> {
+                if(!unsigned || range.first<=127) {
+                    asmgen.out("""
+                        dec  $varname
+                        bpl  $loopLabel""")
+                } else {
+                    asmgen.out("""
+                        dec  $varname
+                        lda  $varname
+                        cmp  #255
+                        bne  $loopLabel""")
+                }
+            }
+            1 -> {
+                asmgen.out("""
+                    dec  $varname
+                    bne  $loopLabel""")
+            }
+            else -> {
+                asmgen.out("""
+                    dec  $varname
+                    lda  $varname
+                    cmp  #${range.last-1}
+                    bne  $loopLabel""")
+            }
+        }
+    }
+
+    private fun translateForSimpleWordRangeAsc(stmt: PtForLoop, range: IntProgression) {
+        val loopLabel = asmgen.makeLabel("for_loop")
+        val endLabel = asmgen.makeLabel("for_end")
+        asmgen.loopEndLabels.add(endLabel)
+        val varname = asmgen.asmVariableName(stmt.variable)
+        asmgen.out("""
+            lda  #<${range.first}
+            ldy  #>${range.first}
+            sta  $varname
+            sty  $varname+1
+$loopLabel""")
+        asmgen.translate(stmt.statements)
+        asmgen.out("""
+            lda  $varname
+            cmp  #<${range.last}
+            bne  +
+            lda  $varname+1
+            cmp  #>${range.last}
+            beq  $endLabel
++           inc  $varname
+            bne  $loopLabel
+            inc  $varname+1""")
+        asmgen.jmp(loopLabel)
+        asmgen.out(endLabel)
+        asmgen.loopEndLabels.removeLast()
+    }
+
+    private fun translateForSimpleWordRangeDesc(stmt: PtForLoop, range: IntProgression) {
+        val loopLabel = asmgen.makeLabel("for_loop")
+        val endLabel = asmgen.makeLabel("for_end")
+        asmgen.loopEndLabels.add(endLabel)
+        val varname = asmgen.asmVariableName(stmt.variable)
+        asmgen.out("""
+            lda  #<${range.first}
+            ldy  #>${range.first}
+            sta  $varname
+            sty  $varname+1
+$loopLabel""")
+        asmgen.translate(stmt.statements)
+        if(range.last==0) {
+            asmgen.out("""
+                lda  $varname
+                bne  ++
+                lda  $varname+1
+                beq  $endLabel""")
+        } else {
+            asmgen.out("""
+                lda  $varname
+                cmp  #<${range.last}
+                bne  +
+                lda  $varname+1
+                cmp  #>${range.last}
+                beq  $endLabel""")
+        }
+        asmgen.out("""
++           lda  $varname
+            bne  +
+            dec  $varname+1
++           dec  $varname""")
+        asmgen.jmp(loopLabel)
+        asmgen.out(endLabel)
+        asmgen.loopEndLabels.removeLast()
+    }
+
+    private fun assignLoopvarWord(stmt: PtForLoop, range: PtRange) =
+        asmgen.assignExpressionToVariable(
+            range.from,
+            asmgen.asmVariableName(stmt.variable),
+            stmt.variable.type)
+}

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

@@ -0,0 +1,379 @@
+package prog8.codegen.cpu6502
+
+import prog8.code.StNodeType
+import prog8.code.ast.*
+import prog8.code.core.*
+import prog8.codegen.cpu6502.assignment.AsmAssignSource
+import prog8.codegen.cpu6502.assignment.AsmAssignTarget
+import prog8.codegen.cpu6502.assignment.AsmAssignment
+import prog8.codegen.cpu6502.assignment.TargetStorageKind
+
+
+internal class FunctionCallAsmGen(private val program: PtProgram, private val asmgen: AsmGen6502Internal) {
+
+    internal fun translateFunctionCallStatement(stmt: PtFunctionCall) {
+        translateFunctionCall(stmt)
+        // just ignore any result values from the function call.
+    }
+
+    internal fun optimizeIntArgsViaCpuRegisters(params: List<PtSubroutineParameter>): Boolean {
+        // When the parameter(s) are passed via an explicit register or register pair,
+        // we consider them NOT to be optimized into (possibly different) CPU registers.
+        // Just load them in whatever the register spec says.
+        return when (params.size) {
+            1 -> params[0].type.isIntegerOrBool && params[0].register == null
+            2 -> params[0].type.isByteOrBool && params[1].type.isByteOrBool && params[0].register == null && params[1].register == null
+            else -> false
+        }
+    }
+
+    internal fun translateFunctionCall(call: PtFunctionCall) {
+        // 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 symbol = asmgen.symbolTable.lookup(call.name)!!
+        if(symbol.type == StNodeType.LABEL) {
+            require(call.void)
+            asmgen.out("  jsr  ${asmgen.asmSymbolName(symbol.scopedName)}")
+            return
+        }
+
+        val sub = symbol.astNode as IPtSubroutine
+        val subAsmName = asmgen.asmSymbolName(call.name)
+
+        if(sub is PtAsmSub) {
+            argumentsViaRegisters(sub, call)
+            if (sub.inline) {
+                // inline the subroutine. (regardless of optimization settings!)
+                // we do this by copying the subroutine's statements at the call site.
+                // NOTE: *if* there is a return statement, it will be the only one, and the very last statement of the subroutine
+                // (this condition has been enforced by an ast check earlier)
+                asmgen.out("  \t; inlined routine follows: ${sub.name}")
+                sub.children.forEach { asmgen.translate(it as PtInlineAssembly) }
+                asmgen.out("  \t; inlined routine end: ${sub.name}")
+            } else {
+                val bank = sub.address?.constbank?.toString()
+                if(bank==null) {
+                    val varbank = if(sub.address?.varbank==null) null else asmgen.asmVariableName(sub.address!!.varbank!!)
+                    if(varbank!=null) {
+                        if(asmgen.options.romable)
+                            TODO("no codegen yet for non-const bank in subroutine call that's usable in ROM  ${call.position}")
+
+                        // self-modifying code: set jsrfar bank argument
+                        when(asmgen.options.compTarget.name) {
+                            "cx16" -> {
+                                // JSRFAR can jump to a banked RAM address as well!
+                                asmgen.out("""
+                                php
+                                pha
+                                lda  $varbank
+                                sta  +
+                                pla
+                                plp
+                                jsr  cx16.JSRFAR
+                                .word  $subAsmName    ; ${sub.address!!.address.toHex()}
++                               .byte  0    ; modified"""
+                                )
+                            }
+                            "c64" -> {
+                                asmgen.out("""
+                                php
+                                pha
+                                lda  $varbank
+                                sta  +
+                                pla
+                                plp
+                                jsr  c64.x16jsrfar
+                                .word  $subAsmName    ; ${sub.address!!.address.toHex()}
++                               .byte  0    ; modified"""
+                                )
+                            }
+                            "c128" -> {
+                                asmgen.out("""
+                                php
+                                pha
+                                lda  $varbank
+                                sta  +
+                                pla
+                                plp
+                                jsr  c128.x16jsrfar
+                                .word  $subAsmName    ; ${sub.address!!.address.toHex()}
++                               .byte  0    ; modified"""
+                                )
+                            }
+                            else -> throw AssemblyError("callfar is not supported on the selected compilation target")
+                        }
+                    } else {
+                        asmgen.out("  jsr  $subAsmName")
+                    }
+                }
+                else {
+                    when(asmgen.options.compTarget.name) {
+                        "cx16" -> {
+                            // JSRFAR can jump to a banked RAM address as well!
+                            asmgen.out("""
+                                jsr cx16.JSRFAR
+                                .word  $subAsmName    ; ${sub.address!!.address.toHex()}
+                                .byte  $bank"""
+                            )
+                        }
+                        "c64" -> {
+                            asmgen.out("""
+                                jsr  c64.x16jsrfar
+                                .word  $subAsmName    ; ${sub.address!!.address.toHex()}
+                                .byte  $bank"""
+                            )
+                        }
+                        "c128" -> {
+                            asmgen.out("""
+                                jsr  c128.x16jsrfar
+                                .word  $subAsmName    ; ${sub.address!!.address.toHex()}
+                                .byte  $bank"""
+                            )
+                        }
+                        else -> throw AssemblyError("callfar is not supported on the selected compilation target")
+                    }
+                }
+            }
+        }
+        else if(sub is PtSub) {
+            if(optimizeIntArgsViaCpuRegisters(sub.parameters)) {
+                // Note that if the args fit into cpu registers, we don't concern ourselves here
+                // if they should be put into regular subroutine parameter variables, or the R0-R15 register variables.
+                // That is now up to the subroutine itself.
+                useCpuRegistersForArgs(call.args, sub)
+            } else {
+                // arguments via variables
+                val paramValues = sub.parameters.zip(call.args)
+                val (normalParams, registerParams) = paramValues.partition { it.first.register == null }
+                if (normalParams.isNotEmpty()) {
+                    for (p in normalParams)
+                        argumentViaVariable(sub, p.first, p.second)
+                }
+                if (registerParams.isNotEmpty()) {
+                    // the R0-R15 'registers' are not really registers. They're just special variables.
+                    for (p in registerParams)
+                        argumentViaVariable(sub, p.first, p.second)
+                }
+            }
+            asmgen.out("  jsr  $subAsmName")
+        }
+        else throw AssemblyError("invalid sub type")
+
+        // remember: dealing with the X register and/or dealing with return values is the responsibility of the caller
+    }
+
+    private fun useCpuRegistersForArgs(args: List<PtExpression>, sub: PtSub) {
+        val params = sub.parameters
+        when(params.size) {
+            1 -> {
+                val register = if (params[0].type.isByteOrBool) RegisterOrPair.A else RegisterOrPair.AY
+                argumentViaRegister(sub, IndexedValue(0, params[0]), args[0], register)
+            }
+            2 -> {
+                if(params[0].type.isByteOrBool && params[1].type.isByteOrBool) {
+                    // 2 byte params, second in Y, first in A
+                    if(asmgen.needAsaveForExpr(args[0]) && !asmgen.needAsaveForExpr(args[1])) {
+                        // first 0 then 1
+                        argumentViaRegister(sub, IndexedValue(0, params[0]), args[0], RegisterOrPair.A)
+                        argumentViaRegister(sub, IndexedValue(1, params[1]), args[1], RegisterOrPair.Y)
+                    } else if(!asmgen.needAsaveForExpr(args[0]) && asmgen.needAsaveForExpr(args[1])) {
+                        // first 1 then 0
+                        argumentViaRegister(sub, IndexedValue(1, params[1]), args[1], RegisterOrPair.Y)
+                        argumentViaRegister(sub, IndexedValue(0, params[0]), args[0], RegisterOrPair.A)
+                    } else {
+                        argumentViaRegister(sub, IndexedValue(0, params[0]), args[0], RegisterOrPair.A)
+                        if (asmgen.needAsaveForExpr(args[1]))
+                            asmgen.out("  pha")
+                        argumentViaRegister(sub, IndexedValue(1, params[1]), args[1], RegisterOrPair.Y)
+                        if (asmgen.needAsaveForExpr(args[1]))
+                            asmgen.out("  pla")
+                    }
+                } else {
+                    throw AssemblyError("cannot use registers for word+byte")
+                }
+            }
+            else -> throw AssemblyError("cannot use cpu registers for >2 arguments")
+        }
+    }
+
+
+    private fun usesOtherRegistersWhileEvaluating(arg: PtExpression): Boolean {
+        return when(arg) {
+            is PtBuiltinFunctionCall -> {
+                if (arg.name in arrayOf("lsb", "msb", "lsw", "msw"))
+                    return usesOtherRegistersWhileEvaluating(arg.args[0])
+                if (arg.name == "mkword")
+                    return usesOtherRegistersWhileEvaluating(arg.args[0]) || usesOtherRegistersWhileEvaluating(arg.args[1])
+                return !arg.isSimple()
+            }
+            is PtAddressOf -> false
+            is PtIdentifier -> false
+            is PtIrRegister -> false
+            is PtMemoryByte -> arg.address !is PtNumber && arg.address !is PtIdentifier
+            is PtNumber -> false
+            is PtBool -> false
+            else -> true
+        }
+    }
+
+    private fun argumentsViaRegisters(sub: PtAsmSub, call: PtFunctionCall) {
+        val registersUsed = mutableListOf<RegisterOrStatusflag>()
+
+        fun usedA() = registersUsed.any {it.registerOrPair==RegisterOrPair.A || it.registerOrPair==RegisterOrPair.AX || it.registerOrPair==RegisterOrPair.AY}
+        fun usedX() = registersUsed.any {it.registerOrPair==RegisterOrPair.X || it.registerOrPair==RegisterOrPair.AX || it.registerOrPair==RegisterOrPair.XY}
+        fun usedY() = registersUsed.any {it.registerOrPair==RegisterOrPair.Y || it.registerOrPair==RegisterOrPair.AY || it.registerOrPair==RegisterOrPair.XY}
+
+        if(sub.parameters.size==1) {
+            argumentViaRegister(sub, IndexedValue(0, sub.parameters.single().second), call.args[0])
+        } else {
+            val optimalEvalOrder = asmsub6502ArgsEvalOrder(sub)
+            optimalEvalOrder.forEach {
+                val param = sub.parameters[it]
+                val arg = call.args[it]
+                registersUsed += if(usesOtherRegistersWhileEvaluating(arg)) {
+                    if(!registersUsed.any{r -> r.statusflag!=null || r.registerOrPair in CpuRegisters})
+                        argumentViaRegister(sub, IndexedValue(it, param.second), arg)
+                    else if(registersUsed.any { r-> r.statusflag!=null }) {
+                        throw AssemblyError("call argument evaluation problem: can't save cpu statusregister parameter ${call.position}")
+                    }
+                    else {
+                        if(usedX()) asmgen.saveRegisterStack(CpuRegister.X, usedA())
+                        if(usedY()) asmgen.saveRegisterStack(CpuRegister.Y, usedA())
+                        if(usedA()) asmgen.saveRegisterStack(CpuRegister.A, usedA())
+                        val used = argumentViaRegister(sub, IndexedValue(it, param.second), arg)
+                        if(usedA()) asmgen.restoreRegisterStack(CpuRegister.A, false)
+                        if(usedY()) asmgen.restoreRegisterStack(CpuRegister.Y, true)
+                        if(usedX()) asmgen.restoreRegisterStack(CpuRegister.X, true)
+                        used
+                    }
+                } else {
+                    argumentViaRegister(sub, IndexedValue(it, param.second), arg)
+                }
+            }
+        }
+    }
+
+    private fun argumentViaVariable(sub: PtSub, parameter: PtSubroutineParameter, value: PtExpression) {
+        // pass parameter via a regular variable (not via registers)
+        if(!isArgumentTypeCompatible(value.type, parameter.type))
+            throw AssemblyError("argument type incompatible")
+
+        val reg = parameter.register
+        if(reg!=null) {
+            require(reg in Cx16VirtualRegisters) { "can only use R0-R15 'registers' here" }
+            val varName = "cx16.${reg.name.lowercase()}"
+            asmgen.assignExpressionToVariable(value, varName, parameter.type)
+        } else {
+            val varName = asmgen.asmVariableName(sub.scopedName + "." + parameter.name)
+            asmgen.assignExpressionToVariable(value, varName, parameter.type)
+        }
+    }
+
+    private fun argumentViaRegister(sub: IPtSubroutine, parameter: IndexedValue<PtSubroutineParameter>, value: PtExpression, registerOverride: RegisterOrPair? = null): RegisterOrStatusflag {
+        // pass argument via a register parameter
+        if(!isArgumentTypeCompatible(value.type, parameter.value.type))
+            throw AssemblyError("argument type incompatible")
+
+        val paramRegister: RegisterOrStatusflag = when(sub) {
+            is PtAsmSub -> if(registerOverride==null) sub.parameters[parameter.index].first else RegisterOrStatusflag(registerOverride, null)
+            is PtSub -> RegisterOrStatusflag(registerOverride!!, null)
+        }
+        val statusflag = paramRegister.statusflag
+        val register = paramRegister.registerOrPair
+        val requiredDt = parameter.value.type
+        if(requiredDt!=value.type) {
+            if(value.type.largerSizeThan(requiredDt))
+                throw AssemblyError("can only convert byte values to word param types")
+        }
+        if (statusflag!=null) {
+            if(requiredDt!=value.type)
+                throw AssemblyError("for statusflag, byte or bool value is required")
+            if (statusflag == Statusflag.Pc) {
+                // this boolean 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 PtNumber -> {
+                        val carrySet = value.number.toInt() != 0
+                        asmgen.out(if(carrySet) "  sec" else "  clc")
+                    }
+                    is PtBool -> {
+                        asmgen.out(if(value.value) "  sec" else "  clc")
+                    }
+                    is PtIdentifier -> {
+                        val sourceName = asmgen.asmVariableName(value)
+                        // note: cannot use X register here to store A because it might be used for other arguments
+                        asmgen.out("""
+                            pha
+                            clc
+                            lda  $sourceName
+                            beq  +
+                            sec  
++                           pla""")
+                    }
+                    else -> {
+                        asmgen.assignExpressionToRegister(value, RegisterOrPair.A)
+                        asmgen.out("  ror  a")
+                    }
+                }
+            } else throw AssemblyError("can only use Carry as status flag parameter")
+            return RegisterOrStatusflag(null, statusflag)
+        }
+        else {
+            // via register or register pair
+            register!!
+            if(requiredDt.largerSizeThan(value.type)) {
+                // we need to sign extend the source, do this via temporary word variable
+                asmgen.assignExpressionToVariable(value, "P8ZP_SCRATCH_W1", DataType.UBYTE)
+                asmgen.signExtendVariableLsb("P8ZP_SCRATCH_W1", value.type.base)
+                asmgen.assignVariableToRegister("P8ZP_SCRATCH_W1", register, null, Position.DUMMY)
+            } else {
+                val scope = value.definingISub()
+                val target: AsmAssignTarget =
+                    if(parameter.value.type.isByte && (register==RegisterOrPair.AX || register == RegisterOrPair.AY || register==RegisterOrPair.XY || register in Cx16VirtualRegisters))
+                        AsmAssignTarget(TargetStorageKind.REGISTER, asmgen, parameter.value.type, scope, value.position, register = register)
+                    else {
+                        AsmAssignTarget.fromRegisters(register, parameter.value.type.isSigned, value.position, scope, asmgen)
+                    }
+                val src = if(value.type.isPassByRef) {
+                    if(value is PtIdentifier) {
+                        val addr = PtAddressOf(Position.DUMMY)
+                        addr.add(value)
+                        addr.parent = scope as PtNode
+                        AsmAssignSource.fromAstSource(addr, program, asmgen).adjustSignedUnsigned(target)
+                    } else {
+                        AsmAssignSource.fromAstSource(value, program, asmgen).adjustSignedUnsigned(target)
+                    }
+                } else {
+                    AsmAssignSource.fromAstSource(value, program, asmgen).adjustSignedUnsigned(target)
+                }
+                asmgen.translateNormalAssignment(AsmAssignment(src, listOf(target), program.memsizer, target.position), scope)
+            }
+            return RegisterOrStatusflag(register, null)
+        }
+    }
+
+    private fun isArgumentTypeCompatible(argType: DataType, paramType: DataType): Boolean {
+        if(argType isAssignableTo paramType)
+            return true
+        if(argType.isBool && paramType.isBool)
+            return true
+        if(argType.isByte && paramType.isByte)
+            return true
+        if(argType.isWord && paramType.isWord)
+            return true
+
+        // we have a special rule for some types.
+        // strings are assignable to UWORD, for example, and vice versa
+        if(argType.isString && paramType.isUnsignedWord)
+            return true
+        if(argType.isUnsignedWord && paramType.isString)
+            return true
+
+        return false
+    }
+}
+
+

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

@@ -0,0 +1,362 @@
+package prog8.codegen.cpu6502
+
+import prog8.code.ast.*
+import prog8.code.core.*
+import prog8.codegen.cpu6502.assignment.AsmAssignTarget
+import prog8.codegen.cpu6502.assignment.AssignmentAsmGen
+import prog8.codegen.cpu6502.assignment.TargetStorageKind
+
+internal class IfExpressionAsmGen(private val asmgen: AsmGen6502Internal, private val assignmentAsmGen: AssignmentAsmGen, private val errors: IErrorReporter) {
+
+    internal fun assignIfExpression(target: AsmAssignTarget, expr: PtIfExpression) {
+        require(target.datatype==expr.type || target.datatype.isUnsignedWord && expr.type.isString)
+        val falseLabel = asmgen.makeLabel("ifexpr_false")
+        val endLabel = asmgen.makeLabel("ifexpr_end")
+        evalIfExpressionConditonAndBranchWhenFalse(expr.condition, falseLabel)
+        when {
+            expr.type.isByteOrBool -> {
+                asmgen.assignExpressionToRegister(expr.truevalue, RegisterOrPair.A)
+                asmgen.jmp(endLabel)
+                asmgen.out(falseLabel)
+                asmgen.assignExpressionToRegister(expr.falsevalue, RegisterOrPair.A)
+                asmgen.out(endLabel)
+                assignmentAsmGen.assignRegisterByte(target, CpuRegister.A, false, false)
+            }
+            expr.type.isWord || expr.type.isString -> {
+                asmgen.assignExpressionToRegister(expr.truevalue, RegisterOrPair.AY)
+                asmgen.jmp(endLabel)
+                asmgen.out(falseLabel)
+                asmgen.assignExpressionToRegister(expr.falsevalue, RegisterOrPair.AY)
+                asmgen.out(endLabel)
+                assignmentAsmGen.assignRegisterpairWord(target, RegisterOrPair.AY)
+            }
+            expr.type.isFloat -> {
+                asmgen.assignExpressionToRegister(expr.truevalue, RegisterOrPair.FAC1, true)
+                asmgen.jmp(endLabel)
+                asmgen.out(falseLabel)
+                asmgen.assignExpressionToRegister(expr.falsevalue, RegisterOrPair.FAC1, true)
+                asmgen.out(endLabel)
+                asmgen.assignRegister(RegisterOrPair.FAC1, target)
+            }
+            else -> throw AssemblyError("weird dt")
+        }
+    }
+
+    private fun evalIfExpressionConditonAndBranchWhenFalse(condition: PtExpression, falseLabel: String) {
+        when (condition) {
+            is PtBinaryExpression -> {
+                val rightDt = condition.right.type
+                return when {
+                    rightDt.isByteOrBool -> translateIfExpressionByteConditionBranch(condition, falseLabel)
+                    rightDt.isWord -> translateIfExpressionWordConditionBranch(condition, falseLabel)
+                    rightDt.isFloat -> translateIfExpressionFloatConditionBranch(condition, falseLabel)
+                    else -> throw AssemblyError("weird dt")
+                }
+            }
+
+            is PtPrefix if condition.operator=="not" -> {
+                throw AssemblyError("not prefix in ifexpression should have been replaced by swapped values")
+            }
+
+            else -> {
+                // the condition is "simple" enough to just assign its 0/1 value to a register and branch on that
+                asmgen.assignConditionValueToRegisterAndTest(condition)
+                asmgen.out("  beq  $falseLabel")
+            }
+        }
+    }
+
+    private fun translateIfExpressionByteConditionBranch(condition: PtBinaryExpression, falseLabel: String) {
+        val signed = condition.left.type.isSigned
+        val constValue = condition.right.asConstInteger()
+        if(constValue==0) {
+            return translateIfCompareWithZeroByteBranch(condition, signed, falseLabel)
+        }
+
+        when(condition.operator) {
+            "==" -> {
+                // if X==value
+                asmgen.assignExpressionToRegister(condition.left, RegisterOrPair.A, signed)
+                asmgen.cmpAwithByteValue(condition.right, false)
+                asmgen.out("  bne  $falseLabel")
+            }
+            "!=" -> {
+                // if X!=value
+                asmgen.assignExpressionToRegister(condition.left, RegisterOrPair.A, signed)
+                asmgen.cmpAwithByteValue(condition.right, false)
+                asmgen.out("  beq  $falseLabel")
+            }
+            in LogicalOperators -> {
+                val regAtarget = AsmAssignTarget(TargetStorageKind.REGISTER, asmgen, DataType.BOOL, condition.definingISub(), condition.position, register=RegisterOrPair.A)
+                if (assignmentAsmGen.optimizedLogicalExpr(condition, regAtarget)) {
+                    asmgen.out("  beq  $falseLabel")
+                } else {
+                    errors.warn("SLOW FALLBACK FOR 'IFEXPR' CODEGEN - ask for support", condition.position)      //  should not occur ;-)
+                    asmgen.assignConditionValueToRegisterAndTest(condition)
+                    asmgen.out("  beq  $falseLabel")
+                }
+            }
+            else -> {
+                // TODO don't store condition as expression result but just use the flags, like a normal PtIfElse translation does
+                // TODO: special cases for <, <=, >, >= above.
+                asmgen.assignConditionValueToRegisterAndTest(condition)
+                asmgen.out("  beq  $falseLabel")
+            }
+        }
+    }
+
+    private fun translateIfExpressionWordConditionBranch(condition: PtBinaryExpression, falseLabel: String) {
+        // TODO can we reuse this whole thing from IfElse ?
+        val constValue = condition.right.asConstInteger()
+        if(constValue!=null) {
+            if (constValue == 0) {
+                when (condition.operator) {
+                    "==" -> return translateWordExprIsZero(condition.left, falseLabel)
+                    "!=" -> return translateWordExprIsNotZero(condition.left, falseLabel)
+                }
+            }
+            if (constValue != 0) {
+                when (condition.operator) {
+                    "==" -> return translateWordExprEqualsNumber(condition.left, constValue, falseLabel)
+                    "!=" -> return translateWordExprNotEqualsNumber(condition.left, constValue, falseLabel)
+                }
+            }
+        }
+        val variable = condition.right as? PtIdentifier
+        if(variable!=null) {
+            when (condition.operator) {
+                "==" -> return translateWordExprEqualsVariable(condition.left, variable, falseLabel)
+                "!=" -> return translateWordExprNotEqualsVariable(condition.left, variable, falseLabel)
+            }
+        }
+
+        // TODO don't store condition as expression result but just use the flags, like a normal PtIfElse translation does
+        asmgen.assignConditionValueToRegisterAndTest(condition)
+        asmgen.out("  beq  $falseLabel")
+    }
+
+    private fun translateIfExpressionFloatConditionBranch(condition: PtBinaryExpression, elseLabel: String) {
+        val constValue = (condition.right as? PtNumber)?.number
+        if(constValue==0.0) {
+            if (condition.operator == "==") {
+                // if FL==0.0
+                asmgen.assignExpressionToRegister(condition.left, RegisterOrPair.FAC1, true)
+                asmgen.out("  jsr  floats.SIGN |  cmp  #0 |  bne  $elseLabel")
+                return
+            } else if(condition.operator=="!=") {
+                // if FL!=0.0
+                asmgen.assignExpressionToRegister(condition.left, RegisterOrPair.FAC1, true)
+                asmgen.out("  jsr  floats.SIGN |  cmp  #0 |  beq  $elseLabel")
+                return
+            }
+        }
+
+        when(condition.operator) {
+            "==" -> {
+                asmgen.translateFloatsEqualsConditionIntoA(condition.left, condition.right)
+                asmgen.out("  beq  $elseLabel")
+            }
+            "!=" -> {
+                asmgen.translateFloatsEqualsConditionIntoA(condition.left, condition.right)
+                asmgen.out("  bne  $elseLabel")
+            }
+            "<" -> {
+                asmgen.translateFloatsLessConditionIntoA(condition.left, condition.right, false)
+                asmgen.out("  beq  $elseLabel")
+            }
+            "<=" -> {
+                asmgen.translateFloatsLessConditionIntoA(condition.left, condition.right, true)
+                asmgen.out("  beq  $elseLabel")
+            }
+            ">" -> {
+                asmgen.translateFloatsLessConditionIntoA(condition.left, condition.right, true)
+                asmgen.out("  bne  $elseLabel")
+            }
+            ">=" -> {
+                asmgen.translateFloatsLessConditionIntoA(condition.left, condition.right, false)
+                asmgen.out("  bne  $elseLabel")
+            }
+            else -> throw AssemblyError("expected comparison operator")
+        }
+    }
+
+    private fun translateWordExprNotEqualsVariable(expr: PtExpression, variable: PtIdentifier, falseLabel: String) {
+        // if w!=variable
+        // TODO reuse code from ifElse?
+        val varRight = asmgen.asmVariableName(variable)
+        if(expr is PtIdentifier) {
+            val varLeft = asmgen.asmVariableName(expr)
+            asmgen.out("""
+                lda  $varLeft
+                cmp  $varRight
+                bne  +
+                lda  $varLeft+1
+                cmp  $varRight+1
+                beq  $falseLabel
++""")
+        } else {
+            asmgen.assignExpressionToRegister(expr, RegisterOrPair.AY)
+            asmgen.out("""
+                cmp  $varRight
+                bne  +
+                cpy  $varRight+1
+                beq  $falseLabel
++""")
+        }
+    }
+
+    private fun translateWordExprEqualsVariable(expr: PtExpression, variable: PtIdentifier, falseLabel: String) {
+        // if w==variable
+        // TODO reuse code from ifElse?
+        val varRight = asmgen.asmVariableName(variable)
+        if(expr is PtIdentifier) {
+            val varLeft = asmgen.asmVariableName(expr)
+            asmgen.out("""
+                lda  $varLeft
+                cmp  $varRight
+                bne  $falseLabel
+                lda  $varLeft+1
+                cmp  $varRight+1
+                bne  $falseLabel""")
+        } else {
+            asmgen.assignExpressionToRegister(expr, RegisterOrPair.AY)
+            asmgen.out("""
+                cmp  $varRight
+                bne  $falseLabel
+                cpy  $varRight+1
+                bne  $falseLabel""")
+        }
+    }
+
+    private fun translateWordExprNotEqualsNumber(expr: PtExpression, number: Int, falseLabel: String) {
+        // if w!=number
+        // TODO reuse code from ifElse?
+        if(expr is PtIdentifier) {
+            val varname = asmgen.asmVariableName(expr)
+            asmgen.out("""
+                lda  $varname
+                cmp  #<$number
+                bne  +
+                lda  $varname+1
+                cmp  #>$number
+                beq  $falseLabel
++""")
+        } else {
+            asmgen.assignExpressionToRegister(expr, RegisterOrPair.AY)
+            asmgen.out("""
+                cmp  #<$number
+                bne  +
+                cpy  #>$number
+                beq  $falseLabel
++""")
+        }
+    }
+
+    private fun translateWordExprEqualsNumber(expr: PtExpression, number: Int, falseLabel: String) {
+        // if w==number
+        // TODO reuse code from ifElse?
+        if(expr is PtIdentifier) {
+            val varname = asmgen.asmVariableName(expr)
+            asmgen.out("""
+                lda  $varname
+                cmp  #<$number
+                bne  $falseLabel
+                lda  $varname+1
+                cmp  #>$number
+                bne  $falseLabel""")
+        } else {
+            asmgen.assignExpressionToRegister(expr, RegisterOrPair.AY)
+            asmgen.out(                """
+                cmp  #<$number
+                bne  $falseLabel
+                cpy  #>$number
+                bne  $falseLabel""")
+        }
+    }
+
+    private fun translateWordExprIsNotZero(expr: PtExpression, falseLabel: String) {
+        // if w!=0
+        // TODO reuse code from ifElse?
+        if(expr is PtIdentifier) {
+            val varname = asmgen.asmVariableName(expr)
+            asmgen.out("""
+                lda  $varname
+                ora  $varname+1
+                beq  $falseLabel""")
+        } else {
+            asmgen.assignExpressionToRegister(expr, RegisterOrPair.AY)
+            asmgen.out("  sty  P8ZP_SCRATCH_REG |  ora  P8ZP_SCRATCH_REG |  beq  $falseLabel")
+        }
+    }
+
+    private fun translateWordExprIsZero(expr: PtExpression, falseLabel: String) {
+        // if w==0
+        // TODO reuse code from ifElse?
+        if(expr is PtIdentifier) {
+            val varname = asmgen.asmVariableName(expr)
+            asmgen.out("""
+                lda  $varname
+                ora  $varname+1
+                bne  $falseLabel""")
+        } else {
+            asmgen.assignExpressionToRegister(expr, RegisterOrPair.AY)
+            asmgen.out("  sty  P8ZP_SCRATCH_REG |  ora  P8ZP_SCRATCH_REG |  bne  $falseLabel")
+        }
+    }
+
+    private fun translateIfCompareWithZeroByteBranch(condition: PtBinaryExpression, signed: Boolean, falseLabel: String) {
+        // optimized code for byte comparisons with 0
+
+        val useBIT = asmgen.checkIfConditionCanUseBIT(condition)
+        if(useBIT!=null) {
+            // use a BIT instruction to test for bit 7 or 6 set/clear
+            val (testForBitSet, variable, bitmask) = useBIT
+            when (bitmask) {
+                128 -> {
+                    // test via bit + N flag
+                    asmgen.out("  bit  ${variable.name}")
+                    if(testForBitSet) asmgen.out("  bpl  $falseLabel")
+                    else asmgen.out("  bmi  $falseLabel")
+                    return
+                }
+                64 -> {
+                    // test via bit + V flag
+                    asmgen.out("  bit  ${variable.name}")
+                    if(testForBitSet) asmgen.out("  bvc  $falseLabel")
+                    else asmgen.out("  bvs  $falseLabel")
+                    return
+                }
+                else -> throw AssemblyError("BIT can only work on bits 7 and 6")
+            }
+        }
+
+        asmgen.assignConditionValueToRegisterAndTest(condition.left)
+        when (condition.operator) {
+            "==" -> asmgen.out("  bne  $falseLabel")
+            "!=" -> asmgen.out("  beq  $falseLabel")
+            ">" -> {
+                if(signed) asmgen.out("  bmi  $falseLabel |  beq  $falseLabel")
+                else asmgen.out("  beq  $falseLabel")
+            }
+            ">=" -> {
+                if(signed) asmgen.out("  bmi  $falseLabel")
+                else { /* always true for unsigned */ }
+            }
+            "<" -> {
+                if(signed) asmgen.out("  bpl  $falseLabel")
+                else asmgen.jmp(falseLabel)
+            }
+            "<=" -> {
+                if(signed) {
+                    // inverted '>'
+                    asmgen.out("""
+                        beq  +
+                        bpl  $falseLabel
++""")
+                } else asmgen.out("  bne  $falseLabel")
+            }
+            else -> throw AssemblyError("expected comparison operator")
+        }
+    }
+
+}

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

@@ -0,0 +1,939 @@
+package prog8.codegen.cpu6502
+
+import prog8.code.*
+import prog8.code.ast.*
+import prog8.code.core.*
+import prog8.codegen.cpu6502.assignment.AsmAssignTarget
+import prog8.codegen.cpu6502.assignment.TargetStorageKind
+import java.time.LocalDate
+import java.time.LocalDateTime
+import kotlin.math.absoluteValue
+
+/**
+ * Generates the main parts of the program:
+ *  - entry/exit code
+ *  - initialization routines
+ *  - blocks
+ *  - subroutines
+ *  - all variables (note: VarDecl ast nodes are *NOT* used anymore for this! now uses IVariablesAndConsts data tables!)
+ */
+internal class ProgramAndVarsGen(
+    val program: PtProgram,
+    val options: CompilationOptions,
+    val errors: IErrorReporter,
+    private val symboltable: SymbolTable,
+    private val functioncallAsmGen: FunctionCallAsmGen,
+    private val asmgen: AsmGen6502Internal,
+    private val allocator: VariableAllocator,
+    private val zeropage: Zeropage
+) {
+    private val compTarget = options.compTarget
+    private val blockVariableInitializers = program.allBlocks().associateWith { it.children.filterIsInstance<PtAssignment>() }
+
+    internal fun generate() {
+        header()
+
+        if(errors.noErrors())  {
+            program.allBlocks().forEach { block2asm(it) }
+
+            // the global list of all floating point constants for the whole program
+            asmgen.out("; global float constants")
+            for (flt in allocator.globalFloatConsts) {
+                val floatFill = compTarget.getFloatAsmBytes(flt.key)
+                val floatvalue = flt.key
+                asmgen.out("${flt.value}\t.byte  $floatFill  ; float $floatvalue")
+            }
+
+            memorySlabs()
+            footer()
+        }
+    }
+
+    private fun header() {
+        val ourName = this.javaClass.name
+        val cpu = when(compTarget.cpu) {
+            CpuType.CPU6502 -> "6502"
+            CpuType.CPU65C02 -> "w65c02"
+            else -> "unsupported"
+        }
+
+        asmgen.out("; $cpu assembly code for '${program.name}'")
+        asmgen.out("; generated by $ourName on ${LocalDateTime.now().withNano(0)}")
+        asmgen.out("; assembler syntax is for the 64tasm cross-assembler")
+        asmgen.out("; output options: output=${options.output} launcher=${options.launcher} zp=${options.zeropage}")
+        asmgen.out("")
+        asmgen.out(".cpu  '$cpu'\n.enc  'none'")
+
+        // the global prog8 variables needed
+        val zp = zeropage
+        asmgen.out("P8ZP_SCRATCH_B1 = ${zp.SCRATCH_B1}")
+        asmgen.out("P8ZP_SCRATCH_REG = ${zp.SCRATCH_REG}")
+        asmgen.out("P8ZP_SCRATCH_W1 = ${zp.SCRATCH_W1}    ; word")
+        asmgen.out("P8ZP_SCRATCH_W2 = ${zp.SCRATCH_W2}    ; word")
+        if(compTarget.name=="c64") {
+            if(options.floats)
+                asmgen.out("PROG8_C64_BANK_CONFIG=31  ; basic+IO+kernal")
+            else
+                asmgen.out("PROG8_C64_BANK_CONFIG=30  ; IO+kernal, no basic")
+        }
+        asmgen.out(".weak")   // hack to allow user to override the following two with command line redefinition (however, just use '-esa' command line option instead!)
+        asmgen.out(".endweak")
+
+        if(options.symbolDefs.isNotEmpty()) {
+            asmgen.out("; -- user supplied symbols on the command line")
+            for((name, value) in options.symbolDefs) {
+                asmgen.out("$name = $value")
+            }
+        }
+
+        if(options.compTarget.customLauncher.isNotEmpty()) {
+            asmgen.out("; ---- custom launcher assembler program ----")
+            asmgen.out("* = ${options.loadAddress.toHex()}")
+            asmgen.out("prog8_program_start\t; start of program label")
+            for(line in options.compTarget.customLauncher) {
+                asmgen.out(line)
+            }
+            return
+        }
+
+        if(options.output == OutputType.LIBRARY) {
+
+            asmgen.out("; ---- library assembler program ----")
+            asmgen.out("* = ${options.loadAddress.toHex()}")
+            asmgen.out("prog8_program_start\t; start of program label")
+            asmgen.out("    jmp  p8b_main.p8s_start")
+            // note: the jmp above has 2 effects:
+            // 1. it prevents 64tass from stripping away all procs as unused code
+            // 2. it functions as the first entrypoint of the library, required anyway, to run the variable initialization/bss clear bootstrap code.
+
+        } else {
+
+            when (options.output) {
+                OutputType.LIBRARY -> { }
+                OutputType.RAW -> {
+                    asmgen.out("; ---- raw assembler program ----")
+                    asmgen.out("* = ${options.loadAddress.toHex()}")
+                    asmgen.out("prog8_program_start\t; start of program label")
+                    asmgen.out("  cld")
+                    asmgen.out("  tsx  ; save stackpointer for sys.exit()")
+                    asmgen.out("  stx  prog8_lib.orig_stackpointer")
+                    if (!options.noSysInit)
+                        asmgen.out("  jsr  p8_sys_startup.init_system")
+                    asmgen.out("  jsr  p8_sys_startup.init_system_phase2")
+                }
+                OutputType.PRG -> {
+                    when (options.launcher) {
+                        CbmPrgLauncherType.BASIC -> {
+                            if (options.loadAddress != options.compTarget.PROGRAM_LOAD_ADDRESS) {
+                                errors.err(
+                                    "BASIC output must have load address ${options.compTarget.PROGRAM_LOAD_ADDRESS.toHex()}",
+                                    program.position
+                                )
+                            }
+                            asmgen.out("; ---- basic program with sys call ----")
+                            asmgen.out("* = ${options.loadAddress.toHex()}")
+                            asmgen.out("prog8_program_start\t; start of program label")
+                            val year = LocalDate.now().year
+                            asmgen.out("  .word  (+), $year")
+                            asmgen.out("  .null  $9e, format(' %d ', prog8_entrypoint), $3a, $8f, ' prog8'")
+                            asmgen.out("+\t.word  0")
+                            asmgen.out("prog8_entrypoint")
+                            asmgen.out("  cld")
+                            asmgen.out("  tsx  ; save stackpointer for sys.exit()")
+                            asmgen.out("  stx  prog8_lib.orig_stackpointer")
+                            if (!options.noSysInit)
+                                asmgen.out("  jsr  p8_sys_startup.init_system")
+                            asmgen.out("  jsr  p8_sys_startup.init_system_phase2")
+                        }
+
+                        CbmPrgLauncherType.NONE -> {
+                            // this is the same as RAW
+                            asmgen.out("; ---- program without basic sys call ----")
+                            asmgen.out("* = ${options.loadAddress.toHex()}")
+                            asmgen.out("prog8_program_start\t; start of program label")
+                            asmgen.out("  cld")
+                            asmgen.out("  tsx  ; save stackpointer for sys.exit()")
+                            asmgen.out("  stx  prog8_lib.orig_stackpointer")
+                            if (!options.noSysInit)
+                                asmgen.out("  jsr  p8_sys_startup.init_system")
+                            asmgen.out("  jsr  p8_sys_startup.init_system_phase2")
+                        }
+                    }
+                }
+                OutputType.XEX -> {
+                    asmgen.out("; ---- atari xex program ----")
+                    asmgen.out("* = ${options.loadAddress.toHex()}")
+                    asmgen.out("prog8_program_start\t; start of program label")
+                    asmgen.out("  cld")
+                    asmgen.out("  tsx  ; save stackpointer for sys.exit()")
+                    asmgen.out("  stx  prog8_lib.orig_stackpointer")
+                    if (!options.noSysInit)
+                        asmgen.out("  jsr  p8_sys_startup.init_system")
+                    asmgen.out("  jsr  p8_sys_startup.init_system_phase2")
+                }
+            }
+
+            if (options.zeropage !in arrayOf(ZeropageType.BASICSAFE, ZeropageType.DONTUSE)) {
+                asmgen.out("""
+                    ; zeropage is clobbered so we need to reset the machine at exit
+                    lda  #>sys.reset_system
+                    pha
+                    lda  #<sys.reset_system
+                    pha""")
+            }
+
+            when (compTarget.name) {
+                "cx16" -> {
+                    if (options.floats)
+                        asmgen.out("  lda  #4 |  sta  $01")    // to use floats, make sure Basic rom is banked in
+                    asmgen.out("  jsr  p8b_main.p8s_start")
+                    asmgen.out("  jmp  p8_sys_startup.cleanup_at_exit")
+                }
+                "c64" -> {
+                    asmgen.out("  jsr  p8b_main.p8s_start")
+                    asmgen.out("  jmp  p8_sys_startup.cleanup_at_exit")
+                }
+                "c128" -> {
+                    asmgen.out("  jsr  p8b_main.p8s_start")
+                    asmgen.out("  jmp  p8_sys_startup.cleanup_at_exit")
+                }
+                else -> {
+                    asmgen.out("  jsr  p8b_main.p8s_start")
+                    asmgen.out("  jmp  p8_sys_startup.cleanup_at_exit")
+                }
+            }
+        }
+    }
+
+    private fun memorySlabs() {
+        if(symboltable.allMemorySlabs.isNotEmpty()) {
+            asmgen.out("; memory slabs\n  .section slabs_BSS")
+            asmgen.out("prog8_slabs\t.block")
+            for (slab in symboltable.allMemorySlabs) {
+                if (slab.align > 1u)
+                    asmgen.out("\t.align  ${slab.align.toHex()}")
+                asmgen.out("${slab.name}\t.fill  ${slab.size}")
+            }
+            asmgen.out("\t.bend\n  .send slabs_BSS")
+        }
+    }
+
+    private fun footer() {
+        var relocateBssVars = false
+        var relocateBssSlabs = false
+        var relocatedBssStart = 0u
+        var relocatedBssEnd = 0u
+
+        if(options.varsGolden) {
+            if(options.compTarget.BSSGOLDENRAM_START == 0u ||
+                options.compTarget.BSSGOLDENRAM_END == 0u ||
+                options.compTarget.BSSGOLDENRAM_END <= options.compTarget.BSSGOLDENRAM_START) {
+                throw AssemblyError("current compilation target hasn't got the golden ram area properly defined or it is simply not available")
+            }
+            relocateBssVars = true
+            relocatedBssStart = options.compTarget.BSSGOLDENRAM_START
+            relocatedBssEnd = options.compTarget.BSSGOLDENRAM_END
+        }
+        else if(options.varsHighBank!=null) {
+            if(options.compTarget.BSSHIGHRAM_START == 0u ||
+                options.compTarget.BSSHIGHRAM_END == 0u ||
+                options.compTarget.BSSHIGHRAM_END <= options.compTarget.BSSHIGHRAM_START) {
+                throw AssemblyError("current compilation target hasn't got the high ram area properly defined or it is simply not available")
+            }
+            if(options.slabsHighBank!=null && options.varsHighBank!=options.slabsHighBank)
+                throw AssemblyError("slabs and vars high bank must be the same")
+            relocateBssVars = true
+            relocatedBssStart = options.compTarget.BSSHIGHRAM_START
+            relocatedBssEnd = options.compTarget.BSSHIGHRAM_END
+        }
+
+        if(options.slabsGolden) {
+            if(options.compTarget.BSSGOLDENRAM_START == 0u ||
+                options.compTarget.BSSGOLDENRAM_END == 0u ||
+                options.compTarget.BSSGOLDENRAM_END <= options.compTarget.BSSGOLDENRAM_START) {
+                throw AssemblyError("current compilation target hasn't got the golden ram area properly defined or it is simply not available")
+            }
+            relocateBssSlabs = true
+            relocatedBssStart = options.compTarget.BSSGOLDENRAM_START
+            relocatedBssEnd = options.compTarget.BSSGOLDENRAM_END
+        }
+        else if(options.slabsHighBank!=null) {
+            if(options.compTarget.BSSHIGHRAM_START == 0u ||
+                options.compTarget.BSSHIGHRAM_END == 0u ||
+                options.compTarget.BSSHIGHRAM_END <= options.compTarget.BSSHIGHRAM_START) {
+                throw AssemblyError("current compilation target hasn't got the high ram area properly defined or it is simply not available")
+            }
+            if(options.varsHighBank!=null && options.varsHighBank!=options.slabsHighBank)
+                throw AssemblyError("slabs and vars high bank must be the same")
+            relocateBssSlabs = true
+            relocatedBssStart = options.compTarget.BSSHIGHRAM_START
+            relocatedBssEnd = options.compTarget.BSSHIGHRAM_END
+        }
+
+        asmgen.out("; bss sections")
+        asmgen.out("PROG8_VARSHIGH_RAMBANK = ${options.varsHighBank ?: 1}")
+        if(relocateBssVars) {
+            if(!relocateBssSlabs)
+                asmgen.out("  .dsection slabs_BSS")
+            asmgen.out("prog8_program_end\t; end of program label for progend()")
+            asmgen.out("  * = ${relocatedBssStart.toHex()}")
+            asmgen.out("  .dsection BSS_NOCLEAR")
+            asmgen.out("prog8_bss_section_start")
+            asmgen.out("  .dsection BSS")
+            if(relocateBssSlabs)
+                asmgen.out("  .dsection slabs_BSS")
+            asmgen.out("  .cerror * > ${relocatedBssEnd.toHex()}, \"too many variables/data for BSS section\"")
+            asmgen.out("prog8_bss_section_size = * - prog8_bss_section_start")
+        } else {
+            asmgen.out("  .dsection BSS_NOCLEAR")
+            asmgen.out("prog8_bss_section_start")
+            asmgen.out("  .dsection BSS")
+            asmgen.out("prog8_bss_section_size = * - prog8_bss_section_start")
+            if(!relocateBssSlabs)
+                asmgen.out("  .dsection slabs_BSS")
+            asmgen.out("prog8_program_end\t; end of program label for progend()")
+            if(relocateBssSlabs) {
+                asmgen.out("  * = ${relocatedBssStart.toHex()}")
+                asmgen.out("  .dsection slabs_BSS")
+                asmgen.out("  .cerror * > ${relocatedBssEnd.toHex()}, \"too many data for slabs_BSS section\"")
+            }
+        }
+
+        if(relocatedBssEnd >= options.memtopAddress)
+            options.memtopAddress = relocatedBssEnd+1u
+
+        asmgen.out("  ; memtop check")
+        asmgen.out("  .cerror * >= ${options.memtopAddress.toHex()}, \"Program too long by \", * - ${(options.memtopAddress-1u).toHex()}, \" bytes, memtop=${options.memtopAddress.toHex()}\"")
+    }
+
+    private fun block2asm(block: PtBlock) {
+        asmgen.out("")
+        asmgen.out("; ---- block: '${block.name}' ----")
+        if(block.options.address!=null)
+            asmgen.out("* = ${block.options.address!!.toHex()}")
+
+        asmgen.out("${block.name}\t" + (if(block.options.forceOutput) ".block" else ".proc"))
+        asmgen.outputSourceLine(block)
+
+        createBlockVariables(block)
+        asmsubs2asm(block.children)
+
+        asmgen.out("")
+
+        val initializers = blockVariableInitializers.getValue(block)
+        val notInitializers = block.children.filterNot { it in initializers }
+        notInitializers.forEach { asmgen.translate(it) }
+
+        // generate subroutine to initialize block-level (global) variables
+        if (initializers.isNotEmpty()) {
+            asmgen.out("prog8_init_vars\t.block")
+            initializers.forEach { assign ->
+                if((assign.value as? PtNumber)?.number != 0.0 || allocator.isZpVar(assign.target.identifier!!.name))
+                    asmgen.translate(assign)
+                else
+                    throw AssemblyError("non-zp variable should not be initialized to zero; it will be zeroed as part of BSS clear")
+                // the other variables that should be set to zero are done so as part of the BSS section clear.
+            }
+            asmgen.out("  rts\n  .bend")
+        }
+
+        asmgen.out(if(block.options.forceOutput) "\n\t.bend" else "\n\t.pend")
+    }
+
+    private fun getVars(scope: StNode): Map<String, StNode> =
+        scope.children.filter { it.value.type in arrayOf(StNodeType.STATICVAR, StNodeType.CONSTANT, StNodeType.MEMVAR) }
+
+    private fun createBlockVariables(block: PtBlock) {
+        val scope = symboltable.lookupUnscopedOrElse(block.name) { throw AssemblyError("lookup") }
+        require(scope.type==StNodeType.BLOCK)
+        val varsInBlock = getVars(scope)
+
+        // Zeropage Variables
+        val varnames = varsInBlock.filter { it.value.type==StNodeType.STATICVAR }.map { it.value.scopedName }.toSet()
+        zeropagevars2asm(varnames)
+
+        // MemDefs and Consts
+        val mvs = varsInBlock
+            .filter { it.value.type==StNodeType.MEMVAR }
+            .map { it.value as StMemVar }
+        val consts = varsInBlock
+            .filter { it.value.type==StNodeType.CONSTANT }
+            .map { it.value as StConstant }
+        memdefsAndConsts2asm(mvs, consts)
+
+        // normal statically allocated variables
+        val variables = varsInBlock
+            .filter { it.value.type==StNodeType.STATICVAR && !allocator.isZpVar(it.value.scopedName) }
+            .map { it.value as StStaticVariable }
+        nonZpVariables2asm(variables)
+    }
+
+    internal fun translateAsmSubroutine(sub: PtAsmSub) {
+        if(sub.inline) {
+            return      // subroutine gets inlined at call site.
+        }
+
+        asmgen.out("")
+
+        val asmStartScope: String
+        val asmEndScope: String
+        if(sub.definingBlock()!!.options.forceOutput) {
+            asmStartScope = ".block"
+            asmEndScope = ".bend"
+        } else {
+            asmStartScope = ".proc"
+            asmEndScope = ".pend"
+        }
+
+        if(sub.address!=null)
+            return  // already done at the memvars section
+
+        // asmsub with most likely just an inline asm in it
+        asmgen.out("${sub.name}\t$asmStartScope")
+        sub.children.forEach { asmgen.translate(it) }
+        asmgen.out("  $asmEndScope")
+    }
+
+
+    internal fun translateSubroutine(sub: PtSub) {
+        asmgen.out("")
+
+        val asmStartScope: String
+        val asmEndScope: String
+        if(sub.definingBlock()!!.options.forceOutput) {
+            asmStartScope = ".block"
+            asmEndScope = ".bend"
+        } else {
+            asmStartScope = ".proc"
+            asmEndScope = ".pend"
+        }
+
+        asmgen.out("${sub.name}\t$asmStartScope")
+
+        val scope = symboltable.lookupOrElse(sub.scopedName) {
+            throw AssemblyError("lookup ${sub.scopedName}")
+        }
+        require(scope.type==StNodeType.SUBROUTINE)
+        val varsInSubroutine = getVars(scope)
+
+        // Zeropage Variables
+        val varnames = varsInSubroutine.filter { it.value.type==StNodeType.STATICVAR }.map { it.value.scopedName }.toSet()
+        zeropagevars2asm(varnames)
+
+        // MemDefs and Consts
+        val mvs = varsInSubroutine
+            .filter { it.value.type==StNodeType.MEMVAR }
+            .map { it.value as StMemVar }
+        val consts = varsInSubroutine
+            .filter { it.value.type==StNodeType.CONSTANT }
+            .map { it.value as StConstant }
+        memdefsAndConsts2asm(mvs, consts)
+
+        asmsubs2asm(sub.children)
+
+        // the main.start subroutine is the program's entrypoint and should perform some initialization logic
+        if((sub.name=="start" || sub.name=="p8s_start") && (sub.definingBlock()!!.name=="main" || sub.definingBlock()!!.name=="p8b_main"))
+            entrypointInitialization()
+
+        val params = sub.parameters
+        if(functioncallAsmGen.optimizeIntArgsViaCpuRegisters(params)) {
+            asmgen.out("; simple int arg(s) passed via cpu register(s)")
+
+            fun varname(param: PtSubroutineParameter): String =
+                if(param.register==null)
+                    param.name
+                else
+                    param.register!!.asScopedNameVirtualReg(param.type).joinToString(".")
+
+            when(params.size) {
+                1 -> {
+                    val dt = params[0].type
+                    val target = AsmAssignTarget(TargetStorageKind.VARIABLE, asmgen, dt, sub, params[0].position, variableAsmName = varname(params[0]))
+                    if(dt.isByteOrBool)
+                        asmgen.assignRegister(RegisterOrPair.A, target)     // single byte in A
+                    else
+                        asmgen.assignRegister(RegisterOrPair.AY, target)    // word in AY
+                }
+                2 -> {
+                    val target1 = AsmAssignTarget(TargetStorageKind.VARIABLE, asmgen, params[0].type, sub, params[0].position, variableAsmName = varname(params[0]))
+                    val target2 = AsmAssignTarget(TargetStorageKind.VARIABLE, asmgen, params[1].type, sub, params[1].position, variableAsmName = varname(params[1]))
+                    if(params[0].type.isByteOrBool && params[1].type.isByteOrBool) {
+                        // 2 byte args, first in A, second in Y
+                        asmgen.assignRegister(RegisterOrPair.A, target1)
+                        asmgen.assignRegister(RegisterOrPair.Y, target2)
+                    } else throw AssemblyError("cannot use registers for word+byte args")
+                }
+                else -> throw AssemblyError("cannot use registers for >2 args")
+            }
+        }
+
+        asmgen.out("; statements")
+        sub.children.forEach { asmgen.translate(it) }
+
+        asmgen.out("; variables")
+        asmgen.out("    .section BSS_NOCLEAR")      // these extra vars are initialized before use
+        val asmGenInfo = asmgen.subroutineExtra(sub)
+        for((dt, name, addr) in asmGenInfo.extraVars) {
+            if(addr!=null)
+                asmgen.out("$name = $addr")
+            else when(dt) {
+                BaseDataType.UBYTE, BaseDataType.BYTE, BaseDataType.BOOL -> asmgen.out("$name    .byte  ?")
+                BaseDataType.UWORD, BaseDataType.WORD -> asmgen.out("$name    .word  ?")
+                BaseDataType.FLOAT -> asmgen.out("$name    .fill  ${options.compTarget.FLOAT_MEM_SIZE}")
+                else -> throw AssemblyError("weird dt for extravar $dt")
+            }
+        }
+        if(asmGenInfo.usedFloatEvalResultVar1)
+            asmgen.out("$subroutineFloatEvalResultVar1    .fill  ${options.compTarget.FLOAT_MEM_SIZE}")
+        if(asmGenInfo.usedFloatEvalResultVar2)
+            asmgen.out("$subroutineFloatEvalResultVar2    .fill  ${options.compTarget.FLOAT_MEM_SIZE}")
+        asmgen.out("  .send BSS_NOCLEAR")
+
+        // normal statically allocated variables
+        val variables = varsInSubroutine
+            .filter { it.value.type==StNodeType.STATICVAR && !allocator.isZpVar(it.value.scopedName) }
+            .map { it.value as StStaticVariable }
+        nonZpVariables2asm(variables)
+
+        asmgen.out("  $asmEndScope")
+    }
+
+    private fun entrypointInitialization() {
+        // zero out the BSS area first, before setting the variable init values
+        // this is mainly to make sure the arrays are all zero'd out at program startup
+        asmgen.out("  jsr  prog8_lib.program_startup_clear_bss")
+
+        // initialize block-level (global) variables at program start
+        blockVariableInitializers.forEach {
+            if (it.value.isNotEmpty())
+                asmgen.out("  jsr  ${it.key.name}.prog8_init_vars")
+        }
+
+        // string and array variables in zeropage that have initializer value, should be initialized
+        val stringVarsWithInitInZp = getZpStringVarsWithInitvalue()
+        val arrayVarsWithInitInZp = getZpArrayVarsWithInitvalue()
+        if(stringVarsWithInitInZp.isNotEmpty() || arrayVarsWithInitInZp.isNotEmpty()) {
+            asmgen.out("; zp str and array initializations")
+            stringVarsWithInitInZp.forEach {
+                val name = asmgen.asmVariableName(it.name)
+                asmgen.out("""
+                    lda  #<${name}
+                    ldy  #>${name}
+                    sta  P8ZP_SCRATCH_W1
+                    sty  P8ZP_SCRATCH_W1+1
+                    lda  #<${name}_init_value
+                    ldy  #>${name}_init_value
+                    jsr  prog8_lib.strcpy""")
+            }
+            arrayVarsWithInitInZp.forEach {
+                val size = it.alloc.size
+                val name = asmgen.asmVariableName(it.name)
+                asmgen.out("""
+                    lda  #<${name}_init_value
+                    ldy  #>${name}_init_value
+                    sta  cx16.r0
+                    sty  cx16.r0+1
+                    lda  #<${name}
+                    ldy  #>${name}
+                    sta  cx16.r1
+                    sty  cx16.r1+1
+                    lda  #<$size
+                    ldy  #>$size
+                    jsr  sys.memcopy""")
+            }
+            asmgen.out("  jmp  +")
+        }
+
+        stringVarsWithInitInZp.forEach {
+            val varname = asmgen.asmVariableName(it.name)+"_init_value"
+            outputStringvar(varname, 0, it.value.second, it.value.first)
+        }
+
+        arrayVarsWithInitInZp.forEach {
+            val varname = asmgen.asmVariableName(it.name)+"_init_value"
+            arrayVariable2asm(varname, it.alloc.dt, 0, it.value, null)
+        }
+
+        asmgen.out("+")
+    }
+
+    private class ZpStringWithInitial(
+        val name: String,
+        val alloc: MemoryAllocator.VarAllocation,
+        val value: Pair<String, Encoding>
+    )
+
+    private class ZpArrayWithInitial(
+        val name: String,
+        val alloc: MemoryAllocator.VarAllocation,
+        val value: StArray
+    )
+
+    private fun getZpStringVarsWithInitvalue(): Collection<ZpStringWithInitial> {
+        val result = mutableListOf<ZpStringWithInitial>()
+        val vars = allocator.zeropageVars.filter { it.value.dt.isString }
+        for (variable in vars) {
+            val scopedName = variable.key
+            val svar = symboltable.lookup(scopedName) as? StStaticVariable
+            if(svar?.initializationStringValue!=null)
+                result.add(ZpStringWithInitial(scopedName, variable.value, svar.initializationStringValue!!))
+        }
+        return result
+    }
+
+    private fun getZpArrayVarsWithInitvalue(): Collection<ZpArrayWithInitial> {
+        val result = mutableListOf<ZpArrayWithInitial>()
+        val vars = allocator.zeropageVars.filter { it.value.dt.isArray }
+        for (variable in vars) {
+            val scopedName = variable.key
+            val svar = symboltable.lookup(scopedName) as? StStaticVariable
+            if(svar?.initializationArrayValue!=null)
+                result.add(ZpArrayWithInitial(scopedName, variable.value, svar.initializationArrayValue!!))
+        }
+        return result
+    }
+
+    private fun zeropagevars2asm(varNames: Set<String>) {
+        val zpVariables = allocator.zeropageVars.filter { it.key in varNames }.toList().sortedBy { it.second.address }
+        for ((scopedName, zpvar) in zpVariables) {
+            if (scopedName.startsWith("cx16.r"))
+                continue        // The 16 virtual registers of the cx16 are not actual variables in zp, they're memory mapped
+            val variable = symboltable.flat.getValue(scopedName) as StStaticVariable
+            if(variable.dt.isSplitWordArray) {
+                val lsbAddr = zpvar.address
+                val msbAddr = zpvar.address + (zpvar.size/2).toUInt()
+                asmgen.out("${scopedName.substringAfterLast('.')}_lsb \t= $lsbAddr \t; zp ${zpvar.dt} (lsbs)")
+                asmgen.out("${scopedName.substringAfterLast('.')}_msb \t= $msbAddr \t; zp ${zpvar.dt} (msbs)")
+            } else {
+                asmgen.out("${scopedName.substringAfterLast('.')} \t= ${zpvar.address} \t; zp ${zpvar.dt}")
+            }
+        }
+    }
+
+    private fun nonZpVariables2asm(variables: List<StStaticVariable>) {
+        asmgen.out("")
+        val (varsNoInit, varsWithInit) = variables.partition { it.uninitialized }
+        if(varsNoInit.isNotEmpty()) {
+            asmgen.out("; non-zeropage variables")
+            val (dirty, clean) = varsNoInit.partition { it.dirty }
+
+            fun generate(section: String, variables: List<StStaticVariable>) {
+                asmgen.out("  .section $section")
+                val (notAligned, aligned) = variables.partition { it.align == 0 }
+                notAligned.sortedWith(compareBy<StStaticVariable> { it.name }.thenBy { it.dt.base }).forEach {
+                    uninitializedVariable2asm(it)
+                }
+                aligned.sortedWith(compareBy<StStaticVariable> { it.align }.thenBy { it.name }.thenBy { it.dt.base })
+                    .forEach { uninitializedVariable2asm(it) }
+                asmgen.out("  .send $section")
+            }
+
+            if(clean.isNotEmpty()) {
+                // clean vars end up in BSS so they're at least cleared to 0 at startup
+                generate("BSS", clean)
+            }
+            if(dirty.isNotEmpty()) {
+                // Dirty vars actually are ALSO are put into BSS so they're cleared to 0 at program startup,
+                // but NOT at each entry of the subroutine they're declared in.
+                // This saves the STZ's instructions in the subroutine, while still having deterministic start state.
+                // So there is no actual difference here when compared to the way non-dirty variables are allocated.
+                generate("BSS", dirty)
+            }
+        }
+
+        if(varsWithInit.isNotEmpty()) {
+            asmgen.out("; non-zeropage variables with init value")
+            val (stringvars, othervars) = varsWithInit.sortedBy { it.name }.partition { it.dt.isString }
+            val (notAlignedStrings, alignedStrings) = stringvars.partition { it.align==0 }
+            val (notAlignedOther, alignedOther) = othervars.partition { it.align==0 }
+            notAlignedStrings.forEach {
+                outputStringvar(
+                    it.name,
+                    it.align,
+                    it.initializationStringValue!!.second,
+                    it.initializationStringValue!!.first
+                )
+                asmgen.romableError("string (${it.dt} ${it.name}) can only be used as read-only in ROMable code", Position.DUMMY, false)     // TODO print warning with position of the var
+            }
+            alignedStrings.sortedBy { it.align }.forEach {
+                outputStringvar(
+                    it.name,
+                    it.align,
+                    it.initializationStringValue!!.second,
+                    it.initializationStringValue!!.first
+                )
+                asmgen.romableError("string (${it.dt} ${it.name}) can only be used as read-only in ROMable code", Position.DUMMY, false)     // TODO print warning with position of the var
+            }
+
+            notAlignedOther.sortedBy { it.type }.forEach {
+                staticVariable2asm(it)
+                if(it.dt.isArray)
+                    asmgen.romableError("array (${it.dt} ${it.name}) can only be used as read-only in ROMable code", Position.DUMMY, false)     // TODO print warning with position of the var
+                else
+                    asmgen.romableError("inlined variable (${it.dt} ${it.name})", Position.DUMMY)       // TODO print warning with position of the var
+            }
+            alignedOther.sortedBy { it.align }.sortedBy { it.type }.forEach {
+                staticVariable2asm(it)
+                if(it.dt.isArray)
+                    asmgen.romableError("array (${it.dt} ${it.name}) can only be used as read-only in ROMable code", Position.DUMMY, false)     // TODO print warning with position of the var
+                else
+                    asmgen.romableError("inlined variable (${it.dt} ${it.name})", Position.DUMMY)       // TODO print warning with position of the var
+            }
+        }
+    }
+
+    private fun uninitializedVariable2asm(variable: StStaticVariable) {
+        val dt = variable.dt
+        when {
+            dt.isBool || dt.isUnsignedByte -> asmgen.out("${variable.name}\t.byte  ?")
+            dt.isSignedByte -> asmgen.out("${variable.name}\t.char  ?")
+            dt.isUnsignedWord -> asmgen.out("${variable.name}\t.word  ?")
+            dt.isSignedWord -> asmgen.out("${variable.name}\t.sint  ?")
+            dt.isFloat -> asmgen.out("${variable.name}\t.fill  ${compTarget.FLOAT_MEM_SIZE}")
+            dt.isSplitWordArray -> {
+                alignVar(variable.align)
+                val numbytesPerHalf = compTarget.memorySize(variable.dt, variable.length!!) / 2
+                asmgen.out("${variable.name}_lsb\t.fill  $numbytesPerHalf")
+                asmgen.out("${variable.name}_msb\t.fill  $numbytesPerHalf")
+            }
+            dt.isArray -> {
+                alignVar(variable.align)
+                val numbytes = compTarget.memorySize(variable.dt, variable.length!!)
+                asmgen.out("${variable.name}\t.fill  $numbytes")
+            }
+            else -> {
+                throw AssemblyError("weird dt")
+            }
+        }
+    }
+
+    private fun alignVar(align: Int) {
+        if(align > 1)
+            asmgen.out("  .align  ${align.toHex()}")
+    }
+
+    private fun staticVariable2asm(variable: StStaticVariable) {
+        if(!variable.dt.isArray && !variable.dt.isString) {
+            throw AssemblyError("static variables with an initialization value can only be an array or a string, not ${variable.dt} (${variable.name} ${variable.astNode?.position}")
+            // because numeric variables are in the BSS section and get initialized via assignment statements
+        }
+
+//        val initialValue: Number =
+//            if(variable.initializationNumericValue!=null) {
+//                if(variable.dt.isFloat)
+//                    variable.initializationNumericValue!!
+//                else
+//                    variable.initializationNumericValue!!.toInt()
+//            } else 0
+//
+
+        val dt=variable.dt
+        when {
+//            dt.isBool || dt.isUnsignedByte -> asmgen.out("${variable.name}\t.byte  ${initialValue.toHex()}")
+//            dt.isSignedByte -> asmgen.out("${variable.name}\t.char  $initialValue")
+//            dt.isUnsignedWord -> asmgen.out("${variable.name}\t.word  ${initialValue.toHex()}")
+//            dt.isSignedWord -> asmgen.out("${variable.name}\t.sint  $initialValue")
+//            dt.isFloat -> {
+//                if(initialValue==0) {
+//                    asmgen.out("${variable.name}\t.byte  0,0,0,0,0  ; float")
+//                } else {
+//                    val floatFill = compTarget.getFloatAsmBytes(initialValue)
+//                    asmgen.out("${variable.name}\t.byte  $floatFill  ; float $initialValue")
+//                }
+//            }
+            dt.isString -> {
+                throw AssemblyError("all string vars should have been interned into prog")
+            }
+            dt.isArray -> {
+                arrayVariable2asm(variable.name, variable.dt, variable.align, variable.initializationArrayValue, variable.length)
+            }
+            else -> {
+                throw AssemblyError("weird dt")
+            }
+        }
+    }
+
+    private fun arrayVariable2asm(varname: String, dt: DataType, align: Int, value: StArray?, orNumberOfZeros: Int?) {
+        alignVar(align)
+        when {
+            dt.isUnsignedByteArray || dt.isBoolArray -> {
+                val data = makeArrayFillDataUnsigned(dt, value, orNumberOfZeros)
+                if (data.size <= 16)
+                    asmgen.out("$varname\t.byte  ${data.joinToString()}")
+                else {
+                    asmgen.out(varname)
+                    for (chunk in data.chunked(16))
+                        asmgen.out("  .byte  " + chunk.joinToString())
+                }
+            }
+            dt.isSignedByteArray -> {
+                val data = makeArrayFillDataSigned(dt, value, orNumberOfZeros)
+                if (data.size <= 16)
+                    asmgen.out("$varname\t.char  ${data.joinToString()}")
+                else {
+                    asmgen.out(varname)
+                    for (chunk in data.chunked(16))
+                        asmgen.out("  .char  " + chunk.joinToString())
+                }
+            }
+            dt.isSplitWordArray -> {
+                if(dt.elementType().isUnsignedWord) {
+                    val data = makeArrayFillDataUnsigned(dt, value, orNumberOfZeros)
+                    asmgen.out("_array_$varname := ${data.joinToString()}")
+                    asmgen.out("${varname}_lsb\t.byte <_array_$varname")
+                    asmgen.out("${varname}_msb\t.byte >_array_$varname")
+                } else {
+                    val data = makeArrayFillDataSigned(dt, value, orNumberOfZeros)
+                    asmgen.out("_array_$varname := ${data.joinToString()}")
+                    asmgen.out("${varname}_lsb\t.byte <_array_$varname")
+                    asmgen.out("${varname}_msb\t.byte >_array_$varname")
+                }
+            }
+            dt.isUnsignedWordArray -> {
+                val data = makeArrayFillDataUnsigned(dt, value, orNumberOfZeros)
+                if (data.size <= 16)
+                    asmgen.out("$varname\t.word  ${data.joinToString()}")
+                else {
+                    asmgen.out(varname)
+                    for (chunk in data.chunked(16))
+                        asmgen.out("  .word  " + chunk.joinToString())
+                }
+            }
+            dt.isSignedWordArray -> {
+                val data = makeArrayFillDataSigned(dt, value, orNumberOfZeros)
+                if (data.size <= 16)
+                    asmgen.out("$varname\t.sint  ${data.joinToString()}")
+                else {
+                    asmgen.out(varname)
+                    for (chunk in data.chunked(16))
+                        asmgen.out("  .sint  " + chunk.joinToString())
+                }
+            }
+            dt.isFloatArray -> {
+                val array = value ?: zeroFilledArray(orNumberOfZeros!!)
+                val floatFills = array.map {
+                    compTarget.getFloatAsmBytes(it.number!!)
+                }
+                asmgen.out(varname)
+                for (f in array.zip(floatFills))
+                    asmgen.out("  .byte  ${f.second}  ; float ${f.first}")
+            }
+            else -> throw AssemblyError("require array dt")
+        }
+    }
+
+    private fun zeroFilledArray(numElts: Int): StArray {
+        val values = mutableListOf<StArrayElement>()
+        repeat(numElts) {
+            values.add(StArrayElement(0.0, null, null))
+        }
+        return values
+    }
+
+    private fun memdefsAndConsts2asm(memvars: Collection<StMemVar>, consts: Collection<StConstant>) {
+        memvars.sortedBy { it.address }.forEach {
+            asmgen.out("  ${it.name} = ${it.address.toHex()}")
+        }
+        consts.sortedBy { it.name }.forEach {
+            if(it.dt==BaseDataType.FLOAT)
+                asmgen.out("  ${it.name} = ${it.value}")
+            else
+                asmgen.out("  ${it.name} = ${it.value.toHex()}")
+        }
+    }
+
+    private fun asmsubs2asm(statements: List<PtNode>) {
+        statements
+            .filter { it is PtAsmSub && it.address!=null }
+            .forEach { asmsub ->
+                asmsub as PtAsmSub
+                val address = asmsub.address!!
+                val bank = if(address.constbank!=null) "; @bank ${address.constbank}"
+                    else if(address.varbank!=null) "; @bank ${address.varbank?.name}"
+                    else ""
+                asmgen.out("  ${asmsub.name} = ${address.address.toHex()} $bank")
+            }
+    }
+
+    private fun outputStringvar(varname: String, align: Int, encoding: Encoding, value: String) {
+        alignVar(align)
+        asmgen.out("$varname\t; $encoding:\"${value.escape().replace("\u0000", "<NULL>")}\"", false)
+        val bytes = compTarget.encodeString(value, encoding).plus(0.toUByte())
+        val outputBytes = bytes.map { "$" + it.toString(16).padStart(2, '0') }
+        for (chunk in outputBytes.chunked(16))
+            asmgen.out("  .byte  " + chunk.joinToString())
+    }
+
+    private fun makeArrayFillDataUnsigned(dt: DataType, value: StArray?, orNumberOfZeros: Int?): List<String> {
+        val array = value ?: zeroFilledArray(orNumberOfZeros!!)
+        return when {
+            dt.isBoolArray ->
+                // byte array can never contain pointer-to types, so treat values as all integers
+                array.map {
+                    if(it.boolean!=null)
+                        if(it.boolean==true) "1" else "0"
+                    else {
+                        val number = it.number!!
+                        if(number==0.0) "0" else "1"
+                    }
+                }
+            dt.isUnsignedByteArray ->
+                // byte array can never contain pointer-to types, so treat values as all integers
+                array.map {
+                    val number = it.number!!.toInt()
+                    "$"+number.toString(16).padStart(2, '0')
+                }
+            dt.isArray && dt.elementType().isUnsignedWord -> array.map {
+                if(it.number!=null) {
+                    "$" + it.number!!.toInt().toString(16).padStart(4, '0')
+                }
+                else if(it.addressOfSymbol!=null) {
+                    val addrOfSymbol = it.addressOfSymbol!!
+                    val symbol = symboltable.lookup(addrOfSymbol)!!
+                    if(symbol is StStaticVariable && symbol.dt.isSplitWordArray)
+                        asmgen.asmSymbolName(addrOfSymbol+"_lsb")  // the _lsb split array comes first in memory
+                    else
+                        asmgen.asmSymbolName(addrOfSymbol)
+                }
+                else
+                    throw AssemblyError("weird array elt")
+            }
+            else -> throw AssemblyError("invalid dt")
+        }
+    }
+
+    private fun makeArrayFillDataSigned(dt: DataType, value: StArray?, orNumberOfZeros: Int?): List<String> {
+        val array = value ?: zeroFilledArray(orNumberOfZeros!!)
+        return when {
+            // byte array can never contain pointer-to types, so treat values as all integers
+            dt.isUnsignedByteArray ->
+                array.map {
+                    val number = it.number!!.toInt()
+                    "$"+number.toString(16).padStart(2, '0')
+                }
+            dt.isSignedByteArray ->
+                array.map {
+                    val number = it.number!!.toInt()
+                    val hexnum = number.absoluteValue.toString(16).padStart(2, '0')
+                    if(number>=0)
+                        "$$hexnum"
+                    else
+                        "-$$hexnum"
+                }
+            dt.isArray && dt.elementType().isUnsignedWord -> array.map {
+                val number = it.number!!.toInt()
+                "$" + number.toString(16).padStart(4, '0')
+            }
+            dt.isArray && dt.elementType().isSignedWord -> array.map {
+                val number = it.number!!.toInt()
+                val hexnum = number.absoluteValue.toString(16).padStart(4, '0')
+                if(number>=0)
+                    "$$hexnum"
+                else
+                    "-$$hexnum"
+            }
+            else -> throw AssemblyError("invalid dt")
+        }
+    }
+
+}

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

@@ -0,0 +1,132 @@
+package prog8.codegen.cpu6502
+
+import com.github.michaelbull.result.fold
+import com.github.michaelbull.result.onSuccess
+import prog8.code.*
+import prog8.code.core.*
+
+
+internal class VariableAllocator(private val symboltable: SymbolTable,
+                                 private val options: CompilationOptions,
+                                 private val errors: IErrorReporter
+) {
+
+    private val zeropage = options.compTarget.zeropage
+    internal val globalFloatConsts = mutableMapOf<Double, String>()     // all float values in the entire program (value -> varname)
+    internal val zeropageVars: Map<String, MemoryAllocator.VarAllocation>
+
+    init {
+        allocateZeropageVariables()
+        zeropageVars = zeropage.allocatedVariables
+    }
+
+    internal fun isZpVar(scopedName: String): Boolean {
+        if(scopedName in zeropageVars)
+            return true
+
+        val v = symboltable.lookup(scopedName)
+        return if(v is StMemVar) v.address <= 255u else false
+    }
+
+    internal fun getFloatAsmConst(number: Double): String {
+        val asmName = globalFloatConsts[number]
+        if(asmName!=null)
+            return asmName
+
+        val newName = "prog8_float_const_${globalFloatConsts.size}"
+        globalFloatConsts[number] = newName
+        return newName
+    }
+
+    /**
+     * Allocate variables into the Zeropage.
+     * The result should be retrieved from the current machine's zeropage object!
+     */
+    private fun allocateZeropageVariables() {
+        if(options.zeropage== ZeropageType.DONTUSE)
+            return
+
+        val allVariables = collectAllVariables(symboltable)
+
+        val numberOfAllocatableVariables = allVariables.size
+        val varsRequiringZp = allVariables.filter { it.zpwish == ZeropageWish.REQUIRE_ZEROPAGE }
+        val varsPreferringZp = allVariables.filter { it.zpwish == ZeropageWish.PREFER_ZEROPAGE }
+        val varsNotZp = allVariables.filter { it.zpwish == ZeropageWish.NOT_IN_ZEROPAGE }
+        val (varsDontCareWithoutAlignment, varsDontCareWithAlignment) = allVariables.filter { it.zpwish == ZeropageWish.DONTCARE }.partition { it.align == 0 }
+        require(varsDontCareWithAlignment.size + varsDontCareWithoutAlignment.size + varsRequiringZp.size + varsPreferringZp.size + varsNotZp.size == numberOfAllocatableVariables)
+
+        var numVariablesAllocatedInZP = 0
+        var numberOfNonIntegerVariables = 0
+
+        varsRequiringZp.forEach { variable ->
+            val result = zeropage.allocate(
+                variable.scopedName,
+                variable.dt,
+                variable.length,
+                variable.astNode?.position ?: Position.DUMMY,
+                errors
+            )
+            result.fold(
+                success = {
+                    numVariablesAllocatedInZP++
+                },
+                failure = {
+                    errors.err(it.message!!, variable.astNode?.position ?: Position.DUMMY)
+                }
+            )
+        }
+
+        if(errors.noErrors()) {
+            varsPreferringZp.forEach { variable ->
+                val result = zeropage.allocate(
+                    variable.scopedName,
+                    variable.dt,
+                    variable.length,
+                    variable.astNode?.position ?: Position.DUMMY,
+                    errors
+                )
+                result.onSuccess { numVariablesAllocatedInZP++ }
+                //  no need to check for allocation error, if there is one, just allocate in normal system ram.
+            }
+
+            // try to allocate the "don't care" interger variables into the zeropage until it is full.
+            // TODO some form of intelligent priorization? most often used variables first? loopcounter vars first? ...?
+            if(errors.noErrors()) {
+                val sortedList = varsDontCareWithoutAlignment.sortedByDescending { it.scopedName }
+                for (variable in sortedList) {
+                    if(variable.dt.isIntegerOrBool) {
+                        if(zeropage.free.isEmpty()) {
+                            break
+                        } else {
+                            val result = zeropage.allocate(
+                                variable.scopedName,
+                                variable.dt,
+                                variable.length,
+                                variable.astNode?.position ?: Position.DUMMY,
+                                errors
+                            )
+                            result.onSuccess { numVariablesAllocatedInZP++ }
+                        }
+                    } else
+                        numberOfNonIntegerVariables++
+                }
+            }
+        }
+
+        // note: no zeropage allocation is done at all for the @nozp variables. This means they will always end up outside the zeropage.
+    }
+
+    private fun collectAllVariables(st: SymbolTable): Collection<StStaticVariable> {
+        val vars = mutableListOf<StStaticVariable>()
+        fun collect(node: StNode) {
+            for(child in node.children) {
+                if(child.value.type == StNodeType.STATICVAR)
+                    vars.add(child.value as StStaticVariable)
+                else
+                    collect(child.value)
+            }
+        }
+        collect(st)
+        return vars.sortedBy { it.dt.base }
+    }
+}

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

@@ -0,0 +1,207 @@
+package prog8.codegen.cpu6502.assignment
+
+import prog8.code.ast.PtBinaryExpression
+import prog8.code.ast.PtExpression
+import prog8.code.core.AssemblyError
+import prog8.code.core.ComparisonOperators
+import prog8.code.core.DataType
+import prog8.code.core.RegisterOrPair
+import prog8.code.target.C64Target
+import prog8.code.target.Cx16Target
+import prog8.codegen.cpu6502.AsmGen6502Internal
+
+//
+// This contains codegen for stack-based evaluation of binary expressions.
+// It uses the CPU stack so depth is limited.
+// It is called "as a last resort" if the optimized codegen path is unable
+// to come up with a special case of the expression.
+//
+internal class AnyExprAsmGen(
+    private val asmgen: AsmGen6502Internal
+) {
+    fun assignAnyExpressionUsingStack(expr: PtBinaryExpression, assign: AsmAssignment): Boolean {
+        when {
+            expr.type.isByteOrBool -> {
+                if(expr.left.type.isByteOrBool && expr.right.type.isByteOrBool)
+                    return assignByteBinExpr(expr, assign)
+                if (expr.left.type.isWord && expr.right.type.isWord) {
+                    require(expr.operator in ComparisonOperators)
+                    throw AssemblyError("words operands comparison -> byte, should have been handled elsewhere")
+                }
+                if (expr.left.type.isFloat && expr.right.type.isFloat) {
+                    require(expr.operator in ComparisonOperators)
+                    return assignFloatBinExpr(expr, assign)
+                }
+                throw AssemblyError("weird expr operand types: ${expr.left.type} and ${expr.right.type}")
+            }
+            expr.type.isWord -> {
+                require(expr.left.type.isWord && expr.right.type.isWord) {
+                    "both operands must be words"
+                }
+                throw AssemblyError("expression should have been handled otherwise: word ${expr.operator} at ${expr.position}")
+            }
+            expr.type.isFloat -> {
+                require(expr.left.type.isFloat && expr.right.type.isFloat) {
+                    "both operands must be floats"
+                }
+                return assignFloatBinExpr(expr, assign)
+            }
+            else -> throw AssemblyError("weird expression type in assignment")
+        }
+    }
+
+    private fun assignByteBinExpr(expr: PtBinaryExpression, assign: AsmAssignment): Boolean {
+        when(expr.operator) {
+            "+" -> {
+                asmgen.assignExpressionToRegister(expr.left, RegisterOrPair.A)
+                asmgen.out("  pha")
+                asmgen.assignExpressionToVariable(expr.right, "P8ZP_SCRATCH_B1", DataType.UBYTE)
+                asmgen.out("  pla |  clc |  adc  P8ZP_SCRATCH_B1")
+                asmgen.assignRegister(RegisterOrPair.A, assign.target)
+                return true
+            }
+            "-" -> {
+                asmgen.assignExpressionToRegister(expr.left, RegisterOrPair.A)
+                asmgen.out("  pha")
+                asmgen.assignExpressionToVariable(expr.right, "P8ZP_SCRATCH_B1", DataType.UBYTE)
+                asmgen.out("  pla |  sec |  sbc  P8ZP_SCRATCH_B1")
+                asmgen.assignRegister(RegisterOrPair.A, assign.target)
+                return true
+            }
+            "*" -> TODO("byte * at ${expr.position}")
+            "/" -> TODO("byte / at ${expr.position}")
+            "<<" -> TODO("byte << at ${expr.position}")
+            ">>" -> TODO("byte >> at ${expr.position}")
+            "%" -> TODO("byte % at ${expr.position}")
+            "and" -> TODO("logical and (with optional shortcircuit) ${expr.position}")
+            "or" -> TODO("logical or (with optional shortcircuit) ${expr.position}")
+            "&" -> {
+                asmgen.assignExpressionToRegister(expr.left, RegisterOrPair.A)
+                asmgen.out("  pha")
+                asmgen.assignExpressionToVariable(expr.right, "P8ZP_SCRATCH_B1", DataType.UBYTE)
+                asmgen.out("  pla |  and  P8ZP_SCRATCH_B1")
+                asmgen.assignRegister(RegisterOrPair.A, assign.target)
+                return true
+            }
+            "|" -> {
+                asmgen.assignExpressionToRegister(expr.left, RegisterOrPair.A)
+                asmgen.out("  pha")
+                asmgen.assignExpressionToVariable(expr.right, "P8ZP_SCRATCH_B1", DataType.UBYTE)
+                asmgen.out("  pla |  ora  P8ZP_SCRATCH_B1")
+                asmgen.assignRegister(RegisterOrPair.A, assign.target)
+                return true
+            }
+            "^", "xor" -> {
+                asmgen.assignExpressionToRegister(expr.left, RegisterOrPair.A)
+                asmgen.out("  pha")
+                asmgen.assignExpressionToVariable(expr.right, "P8ZP_SCRATCH_B1", DataType.UBYTE)
+                asmgen.out("  pla |  eor  P8ZP_SCRATCH_B1")
+                asmgen.assignRegister(RegisterOrPair.A, assign.target)
+                return true
+            }
+            "==" -> TODO("byte == at ${expr.position}")
+            "!=" -> TODO("byte != at ${expr.position}")
+            "<" -> TODO("byte < at ${expr.position}")
+            "<=" -> TODO("byte <= at ${expr.position}")
+            ">" -> TODO("byte > at ${expr.position}")
+            ">=" -> TODO("byte >= at ${expr.position}")
+            else -> return false
+        }
+    }
+
+    private fun assignFloatBinExpr(expr: PtBinaryExpression, assign: AsmAssignment): Boolean {
+        when(expr.operator) {
+            "+" -> {
+                assignFloatOperandsToFACandARG(expr.left, expr.right)
+                asmgen.out("  jsr  floats.FADDT")
+                asmgen.assignRegister(RegisterOrPair.FAC1, assign.target)
+                return true
+            }
+            "-" -> {
+                assignFloatOperandsToFACandARG(expr.right, expr.left)
+                asmgen.out("  jsr  floats.FSUBT")
+                asmgen.assignRegister(RegisterOrPair.FAC1, assign.target)
+                return true
+            }
+            "*" -> {
+                assignFloatOperandsToFACandARG(expr.left, expr.right)
+                asmgen.out("  jsr  floats.FMULTT")
+                asmgen.assignRegister(RegisterOrPair.FAC1, assign.target)
+                return true
+            }
+            "/" -> {
+                assignFloatOperandsToFACandARG(expr.right, expr.left)
+                asmgen.out("  jsr  floats.FDIVT")
+                asmgen.assignRegister(RegisterOrPair.FAC1, assign.target)
+                return true
+            }
+            "==" -> {
+                setupFloatComparisonFAC1vsVarAY(expr)
+                asmgen.out("  jsr  floats.var_fac1_equal_f")
+                asmgen.assignRegister(RegisterOrPair.A, assign.target)
+                return true
+            }
+            "!=" -> {
+                setupFloatComparisonFAC1vsVarAY(expr)
+                asmgen.out("  jsr  floats.var_fac1_notequal_f")
+                asmgen.assignRegister(RegisterOrPair.A, assign.target)
+                return true
+            }
+            "<" -> {
+                setupFloatComparisonFAC1vsVarAY(expr)
+                asmgen.out("  jsr  floats.var_fac1_less_f")
+                asmgen.assignRegister(RegisterOrPair.A, assign.target)
+                return true
+            }
+            ">" -> {
+                setupFloatComparisonFAC1vsVarAY(expr)
+                asmgen.out("  jsr  floats.var_fac1_greater_f")
+                asmgen.assignRegister(RegisterOrPair.A, assign.target)
+                return true
+            }
+            "<=" -> {
+                setupFloatComparisonFAC1vsVarAY(expr)
+                asmgen.out("  jsr  floats.var_fac1_lesseq_f")
+                asmgen.assignRegister(RegisterOrPair.A, assign.target)
+                return true
+            }
+            ">=" -> {
+                setupFloatComparisonFAC1vsVarAY(expr)
+                asmgen.out("  jsr  floats.var_fac1_greatereq_f")
+                asmgen.assignRegister(RegisterOrPair.A, assign.target)
+                return true
+            }
+            else -> TODO("float expression operator ${expr.operator}")
+        }
+    }
+
+    private fun assignFloatOperandsToFACandARG(left: PtExpression, right: PtExpression) {
+        when(asmgen.options.compTarget.name) {
+            C64Target.NAME -> {
+                // C64 math library has a quirk: you have always make sure FAC2/ARG is loaded last (done using CONUPK)
+                // otherwise the result of certain floating point operations such as FDIVT will be wrong.
+                // see https://www.c64-wiki.com/wiki/CONUPK
+                // Unfortunately this means we have to push and pop an intermediary floating point value to and from memory.
+                asmgen.assignExpressionToRegister(right, RegisterOrPair.FAC1, true)
+                asmgen.pushFAC1()
+                asmgen.assignExpressionToRegister(left, RegisterOrPair.FAC1, true)
+                asmgen.popFAC2()
+            }
+            Cx16Target.NAME -> {
+                asmgen.assignExpressionToRegister(left, RegisterOrPair.FAC1, true)
+                if (!right.isSimple()) asmgen.pushFAC1()
+                asmgen.assignExpressionToRegister(right, RegisterOrPair.FAC2, true)
+                if (!right.isSimple()) asmgen.popFAC1()
+            }
+            else -> TODO("don't know how to evaluate float expression for selected compilation target  ${left.position}")
+        }
+    }
+
+    private fun setupFloatComparisonFAC1vsVarAY(expr: PtBinaryExpression) {
+        asmgen.assignExpressionToRegister(expr.left, RegisterOrPair.FAC1, true)
+        if(!expr.right.isSimple()) asmgen.pushFAC1()
+        asmgen.assignExpressionToVariable(expr.right, "floats.floats_temp_var", DataType.FLOAT)
+        if(!expr.right.isSimple()) asmgen.popFAC1()
+        asmgen.out("  lda  #<floats.floats_temp_var |  ldy  #>floats.floats_temp_var")
+    }
+}

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

@@ -0,0 +1,266 @@
+package prog8.codegen.cpu6502.assignment
+
+import prog8.code.ast.*
+import prog8.code.core.*
+import prog8.codegen.cpu6502.AsmGen6502Internal
+
+
+internal enum class TargetStorageKind {
+    VARIABLE,
+    ARRAY,
+    MEMORY,
+    REGISTER,
+    VOID       // assign nothing - used in multi-value assigns for void placeholders
+}
+
+internal enum class SourceStorageKind {
+    LITERALBOOLEAN,
+    LITERALNUMBER,
+    VARIABLE,
+    ARRAY,
+    MEMORY,
+    REGISTER,
+    EXPRESSION,         // expression in ast-form, still to be evaluated
+}
+
+internal class AsmAssignTarget(val kind: TargetStorageKind,
+                               private val asmgen: AsmGen6502Internal,
+                               val datatype: DataType,
+                               val scope: IPtSubroutine?,
+                               val position: Position,
+                               private val variableAsmName: String? = null,
+                               val array: PtArrayIndexer? = null,
+                               val memory: PtMemoryByte? = null,
+                               val register: RegisterOrPair? = null,
+                               val origAstTarget: PtAssignTarget? = null
+                               )
+{
+    val constArrayIndexValue by lazy { array?.index?.asConstInteger()?.toUInt() }
+    val asmVarname: String by lazy {
+        if (array == null)
+            variableAsmName!!
+        else
+            asmgen.asmVariableName(array.variable)
+    }
+
+    init {
+        if(register!=null && !datatype.isNumericOrBool)
+            throw AssemblyError("must be numeric type")
+    }
+
+    companion object {
+        fun fromAstAssignmentMulti(targets: List<PtAssignTarget>, definingSub: IPtSubroutine?, asmgen: AsmGen6502Internal): List<AsmAssignTarget> {
+            return targets.map {
+                if(it.void)
+                    AsmAssignTarget(TargetStorageKind.VOID, asmgen, DataType.UNDEFINED, null, it.position)
+                else
+                    fromAstAssignment(it, definingSub, asmgen)
+            }
+        }
+
+        fun fromAstAssignment(target: PtAssignTarget, definingSub: IPtSubroutine?, asmgen: AsmGen6502Internal): AsmAssignTarget {
+            with(target) {
+                when {
+                    identifier != null -> {
+                        val parameter = asmgen.findSubroutineParameter(identifier!!.name, asmgen)
+                        if (parameter!=null) {
+                            val sub = parameter.definingAsmSub()
+                            if (sub!=null) {
+                                val reg = sub.parameters.single { it.second===parameter }.first
+                                if(reg.statusflag!=null)
+                                    throw AssemblyError("can't assign value to processor statusflag directly")
+                                else
+                                    return AsmAssignTarget(TargetStorageKind.REGISTER, asmgen, type, definingSub, target.position, register=reg.registerOrPair, origAstTarget = this)
+                            }
+                        }
+                        return AsmAssignTarget(TargetStorageKind.VARIABLE, asmgen, type, definingSub, target.position, variableAsmName = asmgen.asmVariableName(identifier!!), origAstTarget =  this)
+                    }
+                    array != null -> return AsmAssignTarget(TargetStorageKind.ARRAY, asmgen, type, definingSub, target.position, array = array, origAstTarget =  this)
+                    memory != null -> return AsmAssignTarget(TargetStorageKind.MEMORY, asmgen, type, definingSub, target.position, memory =  memory, origAstTarget =  this)
+                    else -> throw AssemblyError("weird target")
+                }
+            }
+        }
+
+        fun fromRegisters(registers: RegisterOrPair, signed: Boolean, pos: Position, scope: IPtSubroutine?, asmgen: AsmGen6502Internal): AsmAssignTarget =
+                when(registers) {
+                    RegisterOrPair.A,
+                    RegisterOrPair.X,
+                    RegisterOrPair.Y -> {
+                        val dt = if(signed) DataType.BYTE else DataType.UBYTE
+                        AsmAssignTarget(TargetStorageKind.REGISTER, asmgen, dt, scope, pos, register = registers)
+                    }
+                    RegisterOrPair.AX,
+                    RegisterOrPair.AY,
+                    RegisterOrPair.XY -> {
+                        val dt = if(signed) DataType.WORD else DataType.UWORD
+                        AsmAssignTarget(TargetStorageKind.REGISTER, asmgen, dt, scope, pos, register = registers)
+                    }
+                    RegisterOrPair.FAC1,
+                    RegisterOrPair.FAC2 -> {
+                        AsmAssignTarget(TargetStorageKind.REGISTER, asmgen, DataType.FLOAT, scope, pos, register = registers)
+                    }
+                    RegisterOrPair.R0,
+                    RegisterOrPair.R1,
+                    RegisterOrPair.R2,
+                    RegisterOrPair.R3,
+                    RegisterOrPair.R4,
+                    RegisterOrPair.R5,
+                    RegisterOrPair.R6,
+                    RegisterOrPair.R7,
+                    RegisterOrPair.R8,
+                    RegisterOrPair.R9,
+                    RegisterOrPair.R10,
+                    RegisterOrPair.R11,
+                    RegisterOrPair.R12,
+                    RegisterOrPair.R13,
+                    RegisterOrPair.R14,
+                    RegisterOrPair.R15 -> {
+                        val dt = if(signed) DataType.WORD else DataType.UWORD
+                        AsmAssignTarget(TargetStorageKind.REGISTER, asmgen, dt, scope, pos, register = registers)
+                    }
+                }
+    }
+
+    fun isSameAs(left: PtExpression): Boolean =
+        when(kind) {
+            TargetStorageKind.VARIABLE -> {
+                val scopedName: String = if('.' in asmVarname)
+                    asmVarname
+                else {
+                    val scopeName = (scope as? PtNamedNode)?.scopedName
+                    if (scopeName == null) asmVarname else "$scopeName.$asmVarname"
+                }
+                left is PtIdentifier && left.name==scopedName
+            }
+            TargetStorageKind.ARRAY -> {
+                left is PtArrayIndexer && left isSameAs array!! && left.splitWords==array.splitWords
+            }
+            TargetStorageKind.MEMORY -> {
+                left isSameAs memory!!
+            }
+            TargetStorageKind.REGISTER -> false
+            TargetStorageKind.VOID -> false
+        }
+}
+
+internal class AsmAssignSource(val kind: SourceStorageKind,
+                               private val program: PtProgram,
+                               private val asmgen: AsmGen6502Internal,
+                               val datatype: DataType,
+                               private val variableAsmName: String? = null,
+                               val array: PtArrayIndexer? = null,
+                               val memory: PtMemoryByte? = null,
+                               val register: RegisterOrPair? = null,
+                               val number: PtNumber? = null,
+                               val boolean: PtBool? = null,
+                               val expression: PtExpression? = null
+)
+{
+    val asmVarname: String
+        get() = if(array==null)
+            variableAsmName!!
+        else
+            asmgen.asmVariableName(array.variable)
+
+    companion object {
+        fun fromAstSource(value: PtExpression, program: PtProgram, asmgen: AsmGen6502Internal): AsmAssignSource {
+            val cv = value as? PtNumber
+            if(cv!=null)
+                return AsmAssignSource(SourceStorageKind.LITERALNUMBER, program, asmgen, cv.type, number = cv)
+            val bv = value as? PtBool
+            if(bv!=null)
+                return AsmAssignSource(SourceStorageKind.LITERALBOOLEAN, program, asmgen, DataType.BOOL, boolean = bv)
+
+            return when(value) {
+                // checked above:   is PtNumber -> throw AssemblyError("should have been constant value")
+                is PtString -> throw AssemblyError("string literal value should not occur anymore for asm generation")
+                is PtArray -> throw AssemblyError("array literal value should not occur anymore for asm generation")
+                is PtIdentifier -> {
+                    val parameter = asmgen.findSubroutineParameter(value.name, asmgen)
+                    if(parameter?.definingAsmSub() != null)
+                        throw AssemblyError("can't assign from a asmsub register parameter $value ${value.position}")
+                    val varName=asmgen.asmVariableName(value)
+                    // special case: "cx16.r[0-15]" are 16-bits virtual registers of the commander X16 system
+                    if(value.type.isUnsignedWord && varName.lowercase().startsWith("cx16.r")) {
+                        val regStr = varName.lowercase().substring(5)
+                        val reg = RegisterOrPair.valueOf(regStr.uppercase())
+                        AsmAssignSource(SourceStorageKind.REGISTER, program, asmgen, value.type, register = reg)
+                    } else {
+                        AsmAssignSource(SourceStorageKind.VARIABLE, program, asmgen, value.type, variableAsmName = varName)
+                    }
+                }
+                is PtMemoryByte -> {
+                    AsmAssignSource(SourceStorageKind.MEMORY, program, asmgen, DataType.UBYTE, memory = value)
+                }
+                is PtArrayIndexer -> {
+                    AsmAssignSource(SourceStorageKind.ARRAY, program, asmgen, value.type, array = value)
+                }
+                is PtBuiltinFunctionCall -> {
+                    AsmAssignSource(SourceStorageKind.EXPRESSION, program, asmgen, value.type, expression = value)
+                }
+                is PtFunctionCall -> {
+                    val symbol = asmgen.symbolTable.lookup(value.name) ?: throw AssemblyError("lookup error ${value.name}")
+                    val sub = symbol.astNode as IPtSubroutine
+                    val returnType =
+                        if(sub is PtSub && sub.returns.size>1)
+                            DataType.UNDEFINED      // TODO list of types instead?
+                        else
+                            sub.returnsWhatWhere().firstOrNull { rr -> rr.first.registerOrPair != null || rr.first.statusflag!=null }?.second
+                            ?: throw AssemblyError("can't translate zero return values in assignment")
+                    AsmAssignSource(SourceStorageKind.EXPRESSION, program, asmgen, returnType, expression = value)
+                }
+                else -> {
+                    AsmAssignSource(SourceStorageKind.EXPRESSION, program, asmgen, value.type, expression = value)
+                }
+            }
+        }
+    }
+
+    fun adjustSignedUnsigned(target: AsmAssignTarget): AsmAssignSource {
+        // allow some signed/unsigned relaxations
+
+        fun withAdjustedDt(newType: DataType) =
+                AsmAssignSource(kind, program, asmgen, newType, variableAsmName, array, memory, register, number, boolean, expression)
+
+        if(target.datatype!=datatype) {
+            if(target.datatype.isByte && datatype.isByte) {
+                return withAdjustedDt(target.datatype)
+            } else if(target.datatype.isWord && datatype.isWord) {
+                return withAdjustedDt(target.datatype)
+            }
+        }
+        return this
+    }
+
+}
+
+
+internal sealed class AsmAssignmentBase(val source: AsmAssignSource,
+                                        val targets: List<AsmAssignTarget>,
+                                        val memsizer: IMemSizer,
+                                        val position: Position) {
+    init {
+        targets.forEach { target ->
+            if (!source.datatype.isArray && !source.datatype.isUndefined && !target.datatype.isArray && !target.datatype.isUndefined)
+                require(memsizer.memorySize(source.datatype, null) <= memsizer.memorySize(target.datatype, null)) {
+                    "source dt size must be less or equal to target dt size at $position srcdt=${source.datatype} targetdt=${target.datatype}"
+                }
+        }
+    }
+
+    val target: AsmAssignTarget
+        get() = targets.single()
+}
+
+internal class AsmAssignment(source: AsmAssignSource,
+                             targets: List<AsmAssignTarget>,
+                             memsizer: IMemSizer,
+                             position: Position): AsmAssignmentBase(source, targets, memsizer, position)
+
+internal class AsmAugmentedAssignment(source: AsmAssignSource,
+                                      val operator: String,
+                                      target: AsmAssignTarget,
+                                      memsizer: IMemSizer,
+                                      position: Position): AsmAssignmentBase(source, listOf(target), memsizer, position)
+