sponsorship link.

error sorting.
version.

.github/FUNDING.yml

@@ -0,0 +1,13 @@
+# 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']

.github/workflows/all-ci.yml

@@ -0,0 +1,36 @@
+name: Build and Test the Prog8 compiler
+
+on:
+  push:
+  workflow_dispatch:
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v3
+
+      - 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@v3
+        with:
+          java-version: 11
+          distribution: adopt
+
+      - name: Build and test with Gradle
+        run: ./gradlew build shadowJar --no-daemon
+
+      - name: Create compiler shadowJar artifact
+        uses: actions/upload-artifact@v3
+        with:
+          name: prog8-compiler-jar-zipped
+          path: compiler/build/libs/*-all.jar

.gitignore

@@ -15,6 +15,7 @@ out/
 parser/**/*.interp
 parser/**/*.tokens
 parser/**/*.java
+compiler/src/prog8/buildversion/*
 *.py[cod]
 *.egg
 *.egg-info
@@ -29,6 +30,8 @@ parsetab.py
 compiler/lib/
 
 .gradle
+**/BuildVersion.kt
 /prog8compiler.jar
 sd*.img
 *.d64
+

.idea/kotlinc.xml

@@ -0,0 +1,9 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="Kotlin2JvmCompilerArguments">
+    <option name="jvmTarget" value="11" />
+  </component>
+  <component name="KotlinJpsPluginSettings">
+    <option name="version" value="1.9.20" />
+  </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-jdk8:1.9.22" />
     <CLASSES>
-      <root url="jar://$KOTLIN_BUNDLED$/lib/kotlin-stdlib.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk8/1.9.22/kotlin-stdlib-jdk8-1.9.22.jar!/" />
-      <root url="jar://$KOTLIN_BUNDLED$/lib/kotlin-reflect.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/1.9.22/kotlin-stdlib-1.9.22.jar!/" />
-      <root url="jar://$KOTLIN_BUNDLED$/lib/kotlin-test.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/annotations/13.0/annotations-13.0.jar!/" />
-      <root url="jar://$KOTLIN_BUNDLED$/lib/kotlin-stdlib-jdk7.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk7/1.9.22/kotlin-stdlib-jdk7-1.9.22.jar!/" />
-      <root url="jar://$KOTLIN_BUNDLED$/lib/kotlin-stdlib-jdk8.jar!/" />
     </CLASSES>
-    <JAVADOC />
+    <JAVADOC>
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk8/1.9.22/kotlin-stdlib-jdk8-1.9.22-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!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk7/1.9.22/kotlin-stdlib-jdk7-1.9.22-javadoc.jar!/" />
+    </JAVADOC>
     <SOURCES>
-      <root url="jar://$KOTLIN_BUNDLED$/lib/kotlin-stdlib-sources.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk8/1.9.22/kotlin-stdlib-jdk8-1.9.22-sources.jar!/" />
-      <root url="jar://$KOTLIN_BUNDLED$/lib/kotlin-reflect-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://$KOTLIN_BUNDLED$/lib/kotlin-test-sources.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/annotations/13.0/annotations-13.0-sources.jar!/" />
-      <root url="jar://$KOTLIN_BUNDLED$/lib/kotlin-stdlib-jdk7-sources.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk7/1.9.22/kotlin-stdlib-jdk7-1.9.22-sources.jar!/" />
-      <root url="jar://$KOTLIN_BUNDLED$/lib/kotlin-stdlib-jdk8-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:antlr4:4.11.1">
+    <properties maven-id="org.antlr:antlr4:4.13.1">
       <exclude>
         <dependency maven-id="com.ibm.icu:icu4j" />
       </exclude>
     </properties>
     <CLASSES>
-      <root url="jar://$MAVEN_REPOSITORY$/org/antlr/antlr4/4.11.1/antlr4-4.11.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/antlr/antlr4/4.13.1/antlr4-4.13.1.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/antlr/antlr4-runtime/4.11.1/antlr4-runtime-4.11.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/antlr/antlr4-runtime/4.13.1/antlr4-runtime-4.13.1.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/antlr/antlr-runtime/3.5.3/antlr-runtime-3.5.3.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/antlr/ST4/4.3.4/ST4-4.3.4.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/abego/treelayout/org.abego.treelayout.core/1.0.3/org.abego.treelayout.core-1.0.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/glassfish/javax.json/1.1.4/javax.json-1.1.4.jar!/" />
     </CLASSES>
     <JAVADOC />
     <SOURCES />

.idea/libraries/github_hypfvieh_dbus_java.xml

@@ -1,23 +1,23 @@
 <component name="libraryTable">
   <library name="github.hypfvieh.dbus.java" type="repository">
-    <properties maven-id="com.github.hypfvieh:dbus-java:3.3.1" />
+    <properties maven-id="com.github.hypfvieh:dbus-java:3.3.2" />
     <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/hypfvieh/dbus-java/3.3.2/dbus-java-3.3.2.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-unixsocket/0.38.17/jnr-unixsocket-0.38.17.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/jnr-ffi/2.2.11/jnr-ffi-2.2.11.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/1.3.9/jffi-1.3.9.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/com/github/jnr/jffi/1.3.1/jffi-1.3.1-native.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/com/github/jnr/jffi/1.3.9/jffi-1.3.9-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/9.2/asm-9.2.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-commons/9.2/asm-commons-9.2.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-analysis/9.2/asm-analysis-9.2.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-tree/9.2/asm-tree-9.2.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/ow2/asm/asm-util/9.1/asm-util-9.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/ow2/asm/asm-util/9.2/asm-util-9.2.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-constants/0.10.3/jnr-constants-0.10.3.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-enxio/0.32.13/jnr-enxio-0.32.13.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/com/github/jnr/jnr-posix/3.1.5/jnr-posix-3.1.5.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/com/github/jnr/jnr-posix/3.1.15/jnr-posix-3.1.15.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/slf4j/slf4j-api/1.7.30/slf4j-api-1.7.30.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/slf4j/slf4j-api/1.7.36/slf4j-api-1.7.36.jar!/" />
     </CLASSES>
     <JAVADOC />
     <SOURCES />

.idea/libraries/io_kotest_assertions_core_jvm.xml

@@ -1,21 +1,21 @@
 <component name="libraryTable">
   <library name="io.kotest.assertions.core.jvm" type="repository">
-    <properties maven-id="io.kotest:kotest-assertions-core-jvm:5.3.2" />
+    <properties maven-id="io.kotest:kotest-assertions-core-jvm:5.8.0" />
     <CLASSES>
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-core-jvm/5.3.2/kotest-assertions-core-jvm-5.3.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-core-jvm/5.8.0/kotest-assertions-core-jvm-5.8.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk8/1.6.21/kotlin-stdlib-jdk8-1.6.21.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk8/1.8.10/kotlin-stdlib-jdk8-1.8.10.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/1.6.21/kotlin-stdlib-1.6.21.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/1.8.10/kotlin-stdlib-1.8.10.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/annotations/13.0/annotations-13.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk7/1.8.10/kotlin-stdlib-jdk7-1.8.10.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk7/1.6.21/kotlin-stdlib-jdk7-1.6.21.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-shared-jvm/5.8.0/kotest-assertions-shared-jvm-5.8.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-shared-jvm/5.3.2/kotest-assertions-shared-jvm-5.3.2.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://$MAVEN_REPOSITORY$/io/github/java-diff-utils/java-diff-utils/4.11/java-diff-utils-4.11.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/opentest4j/opentest4j/1.3.0/opentest4j-1.3.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/opentest4j/opentest4j/1.2.0/opentest4j-1.2.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-common/1.8.10/kotlin-stdlib-common-1.8.10.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-jdk8/1.6.1/kotlinx-coroutines-jdk8-1.6.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-jdk8/1.7.0/kotlinx-coroutines-jdk8-1.7.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-reflect/1.6.21/kotlin-reflect-1.6.21.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-reflect/1.8.10/kotlin-reflect-1.8.10.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-core-jvm/1.6.1/kotlinx-coroutines-core-jvm-1.6.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-common-jvm/5.8.0/kotest-common-jvm-5.8.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-common/1.6.0/kotlin-stdlib-common-1.6.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-api-jvm/5.8.0/kotest-assertions-api-jvm-5.8.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-common-jvm/5.3.2/kotest-common-jvm-5.3.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-core-jvm/1.7.0/kotlinx-coroutines-core-jvm-1.7.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-api-jvm/5.3.2/kotest-assertions-api-jvm-5.3.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/annotations/23.0.0/annotations-23.0.0.jar!/" />
     </CLASSES>
     <JAVADOC />
     <SOURCES />

.idea/libraries/io_kotest_property_jvm.xml

@@ -1,24 +0,0 @@
-<component name="libraryTable">
-  <library name="io.kotest.property.jvm" type="repository">
-    <properties maven-id="io.kotest:kotest-property-jvm:5.3.2" />
-    <CLASSES>
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-property-jvm/5.3.2/kotest-property-jvm-5.3.2.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/com/github/curious-odd-man/rgxgen/1.3/rgxgen-1.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk8/1.6.21/kotlin-stdlib-jdk8-1.6.21.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/1.6.21/kotlin-stdlib-1.6.21.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-jdk7/1.6.21/kotlin-stdlib-jdk7-1.6.21.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-common-jvm/5.3.2/kotest-common-jvm-5.3.2.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-shared-jvm/5.3.2/kotest-assertions-shared-jvm-5.3.2.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-api-jvm/5.3.2/kotest-assertions-api-jvm-5.3.2.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-jdk8/1.6.1/kotlinx-coroutines-jdk8-1.6.1.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/opentest4j/opentest4j/1.2.0/opentest4j-1.2.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/github/java-diff-utils/java-diff-utils/4.11/java-diff-utils-4.11.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-reflect/1.6.21/kotlin-reflect-1.6.21.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-core-jvm/1.6.1/kotlinx-coroutines-core-jvm-1.6.1.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-common/1.6.0/kotlin-stdlib-common-1.6.0.jar!/" />
-    </CLASSES>
-    <JAVADOC />
-    <SOURCES />
-  </library>
-</component>

.idea/libraries/io_kotest_runner_junit5_jvm.xml

@@ -1,51 +1,42 @@
 <component name="libraryTable">
   <library name="io.kotest.runner.junit5.jvm" type="repository">
-    <properties maven-id="io.kotest:kotest-runner-junit5-jvm:5.3.2" />
+    <properties maven-id="io.kotest:kotest-runner-junit5-jvm:5.8.0" />
     <CLASSES>
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-runner-junit5-jvm/5.3.2/kotest-runner-junit5-jvm-5.3.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-runner-junit5-jvm/5.8.0/kotest-runner-junit5-jvm-5.8.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-framework-api-jvm/5.3.2/kotest-framework-api-jvm-5.3.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-framework-api-jvm/5.8.0/kotest-framework-api-jvm-5.8.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-shared-jvm/5.3.2/kotest-assertions-shared-jvm-5.3.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-shared-jvm/5.8.0/kotest-assertions-shared-jvm-5.8.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/github/java-diff-utils/java-diff-utils/4.11/java-diff-utils-4.11.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/1.6.1/kotlinx-coroutines-test-jvm-1.6.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-test-jvm/1.7.0/kotlinx-coroutines-test-jvm-1.7.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-common-jvm/5.3.2/kotest-common-jvm-5.3.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-common-jvm/5.8.0/kotest-common-jvm-5.8.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-framework-engine-jvm/5.3.2/kotest-framework-engine-jvm-5.3.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-framework-engine-jvm/5.8.0/kotest-framework-engine-jvm-5.8.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/github/classgraph/classgraph/4.8.146/classgraph-4.8.146.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/github/classgraph/classgraph/4.8.162/classgraph-4.8.162.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/com/github/ajalt/mordant/1.2.1/mordant-1.2.1.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/com/github/ajalt/colormath/1.2.0/colormath-1.2.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/opentest4j/opentest4j/1.2.0/opentest4j-1.2.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/opentest4j/opentest4j/1.3.0/opentest4j-1.3.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-debug/1.6.1/kotlinx-coroutines-debug-1.6.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-debug/1.7.0/kotlinx-coroutines-debug-1.7.0.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/net/java/dev/jna/jna/5.9.0/jna-5.9.0.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/net/java/dev/jna/jna-platform/5.9.0/jna-platform-5.9.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-framework-discovery-jvm/5.3.2/kotest-framework-discovery-jvm-5.3.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/net/bytebuddy/byte-buddy/1.10.9/byte-buddy-1.10.9.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-core-jvm/5.3.2/kotest-assertions-core-jvm-5.3.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/net/bytebuddy/byte-buddy-agent/1.10.9/byte-buddy-agent-1.10.9.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-jdk8/1.6.1/kotlinx-coroutines-jdk8-1.6.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-framework-discovery-jvm/5.8.0/kotest-framework-discovery-jvm-5.8.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-api-jvm/5.3.2/kotest-assertions-api-jvm-5.3.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-core-jvm/5.8.0/kotest-assertions-core-jvm-5.8.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-extensions-jvm/5.3.2/kotest-extensions-jvm-5.3.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-jdk8/1.7.0/kotlinx-coroutines-jdk8-1.7.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/commons-io/commons-io/2.11.0/commons-io-2.11.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-api-jvm/5.8.0/kotest-assertions-api-jvm-5.8.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/mockk/mockk/1.12.3/mockk-1.12.3.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-extensions-jvm/5.8.0/kotest-extensions-jvm-5.8.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/mockk/mockk-common/1.12.3/mockk-common-1.12.3.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-framework-concurrency-jvm/5.8.0/kotest-framework-concurrency-jvm-5.8.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/mockk/mockk-dsl/1.12.3/mockk-dsl-1.12.3.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-core-jvm/1.7.0/kotlinx-coroutines-core-jvm-1.7.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/mockk/mockk-dsl-jvm/1.12.3/mockk-dsl-jvm-1.12.3.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/annotations/23.0.0/annotations-23.0.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/mockk/mockk-agent-jvm/1.12.3/mockk-agent-jvm-1.12.3.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://$MAVEN_REPOSITORY$/io/mockk/mockk-agent-api/1.12.3/mockk-agent-api-1.12.3.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://$MAVEN_REPOSITORY$/io/mockk/mockk-agent-common/1.12.3/mockk-agent-common-1.12.3.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/objenesis/objenesis/3.1/objenesis-3.1.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://$MAVEN_REPOSITORY$/net/bytebuddy/byte-buddy/1.12.6/byte-buddy-1.12.6.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://$MAVEN_REPOSITORY$/net/bytebuddy/byte-buddy-agent/1.12.6/byte-buddy-agent-1.12.6.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://$MAVEN_REPOSITORY$/io/kotest/kotest-framework-concurrency-jvm/5.3.2/kotest-framework-concurrency-jvm-5.3.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk8/1.8.10/kotlin-stdlib-jdk8-1.8.10.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-core-jvm/1.6.1/kotlinx-coroutines-core-jvm-1.6.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/1.8.10/kotlin-stdlib-1.8.10.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-common/1.6.0/kotlin-stdlib-common-1.6.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk7/1.8.10/kotlin-stdlib-jdk7-1.8.10.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/junit/platform/junit-platform-engine/1.7.2/junit-platform-engine-1.7.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-common/1.8.10/kotlin-stdlib-common-1.8.10.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/apiguardian/apiguardian-api/1.1.0/apiguardian-api-1.1.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-reflect/1.8.10/kotlin-reflect-1.8.10.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/junit/platform/junit-platform-commons/1.7.2/junit-platform-commons-1.7.2.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/junit/platform/junit-platform-suite-api/1.7.2/junit-platform-suite-api-1.7.2.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/junit/platform/junit-platform-launcher/1.7.2/junit-platform-launcher-1.7.2.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/junit/jupiter/junit-jupiter-api/5.7.2/junit-jupiter-api-5.7.2.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk8/1.6.21/kotlin-stdlib-jdk8-1.6.21.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/1.6.21/kotlin-stdlib-1.6.21.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-jdk7/1.6.21/kotlin-stdlib-jdk7-1.6.21.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-reflect/1.6.21/kotlin-reflect-1.6.21.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:0.3.4" />
+    <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/0.3.4/kotlinx-cli-jvm-0.3.4.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

@@ -1,13 +1,13 @@
 <component name="libraryTable">
   <library name="michael.bull.kotlin.result.jvm" type="repository">
-    <properties maven-id="com.michael-bull.kotlin-result:kotlin-result-jvm:1.1.16" />
+    <properties maven-id="com.michael-bull.kotlin-result:kotlin-result-jvm:1.1.18" />
     <CLASSES>
-      <root url="jar://$MAVEN_REPOSITORY$/com/michael-bull/kotlin-result/kotlin-result-jvm/1.1.16/kotlin-result-jvm-1.1.16.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/com/michael-bull/kotlin-result/kotlin-result-jvm/1.1.18/kotlin-result-jvm-1.1.18.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-common/1.6.20/kotlin-stdlib-common-1.6.20.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk8/1.8.10/kotlin-stdlib-jdk8-1.8.10.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk8/1.6.20/kotlin-stdlib-jdk8-1.6.20.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/1.8.10/kotlin-stdlib-1.8.10.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/1.6.20/kotlin-stdlib-1.6.20.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-jdk7/1.6.20/kotlin-stdlib-jdk7-1.6.20.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk7/1.8.10/kotlin-stdlib-jdk7-1.8.10.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-common/1.8.10/kotlin-stdlib-common-1.8.10.jar!/" />
     </CLASSES>
     <JAVADOC />
     <SOURCES />

.idea/libraries/slf4j_simple.xml

@@ -1,9 +1,9 @@
 <component name="libraryTable">
   <library name="slf4j.simple" type="repository">
-    <properties maven-id="org.slf4j:slf4j-simple:1.7.36" />
+    <properties maven-id="org.slf4j:slf4j-simple:2.0.11" />
     <CLASSES>
-      <root url="jar://$MAVEN_REPOSITORY$/org/slf4j/slf4j-simple/1.7.36/slf4j-simple-1.7.36.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/slf4j/slf4j-simple/2.0.11/slf4j-simple-2.0.11.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/slf4j/slf4j-api/1.7.36/slf4j-api-1.7.36.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/slf4j/slf4j-api/2.0.11/slf4j-api-2.0.11.jar!/" />
     </CLASSES>
     <JAVADOC />
     <SOURCES />

.idea/libraries/takes.xml

@@ -1,15 +1,16 @@
 <component name="libraryTable">
   <library name="takes" type="repository">
-    <properties maven-id="org.takes:takes:1.20" />
+    <properties maven-id="org.takes:takes:1.24.4" />
     <CLASSES>
-      <root url="jar://$MAVEN_REPOSITORY$/org/takes/takes/1.20/takes-1.20.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/takes/takes/1.24.4/takes-1.24.4.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/cactoos/cactoos/0.50/cactoos-0.50.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/cactoos/cactoos/0.54.0/cactoos-0.54.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/javax/xml/bind/jaxb-api/2.3.0/jaxb-api-2.3.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/javax/xml/bind/jaxb-api/2.4.0-b180830.0359/jaxb-api-2.4.0-b180830.0359.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/slf4j/slf4j-api/1.7.25/slf4j-api-1.7.25.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/javax/activation/javax.activation-api/1.2.0/javax.activation-api-1.2.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/apache/commons/commons-text/1.4/commons-text-1.4.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/com/sun/xml/bind/jaxb-core/4.0.0/jaxb-core-4.0.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/apache/commons/commons-lang3/3.7/commons-lang3-3.7.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/jakarta/xml/bind/jakarta.xml.bind-api/4.0.0/jakarta.xml.bind-api-4.0.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/com/sun/xml/bind/jaxb-core/2.3.0/jaxb-core-2.3.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/jakarta/activation/jakarta.activation-api/2.1.0/jakarta.activation-api-2.1.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/com/sun/xml/bind/jaxb-impl/2.3.0/jaxb-impl-2.3.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/eclipse/angus/angus-activation/1.0.0/angus-activation-1.0.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/com/sun/xml/bind/jaxb-impl/4.0.0/jaxb-impl-4.0.0.jar!/" />
     </CLASSES>
     <JAVADOC />
     <SOURCES />

.idea/misc.xml

@@ -16,10 +16,13 @@
       </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" default="true" project-jdk-name="11" project-jdk-type="JavaSDK">
+  <component name="ProjectRootManager" version="2" languageLevel="JDK_11" default="true" project-jdk-name="openjdk-11" project-jdk-type="JavaSDK">
     <output url="file://$PROJECT_DIR$/out" />
   </component>
 </project>

.readthedocs.yaml

@@ -7,13 +7,9 @@ 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"
+    python: "3.11"
-    # You can also specify other tool versions:
-    # nodejs: "16"
-    # rust: "1.55"
-    # golang: "1.17"
 
 # Build documentation in the docs/ directory with Sphinx
 sphinx:

CompilerDevelopment.md

@@ -1,35 +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:
-
-(note: all these steps have been implemented, rejected or otherwise solved now.)
-
-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
-

README.md

@@ -1,3 +1,4 @@
+[![ko-fi](https://ko-fi.com/img/githubbutton_sm.svg)](https://ko-fi.com/H2H6S0FFF)
 [![Documentation](https://readthedocs.org/projects/prog8/badge/?version=latest)](https://prog8.readthedocs.io/)
 
 Prog8 - Structured Programming Language for 8-bit 6502/65c02 microprocessors
@@ -9,11 +10,33 @@ 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). 
+
+
 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).
+
+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), with exception for generated code:
@@ -59,6 +82,8 @@ What does Prog8 provide?
 - "c64": Commodore-64  (6502 like CPU)
 - "c128": Commodore-128  (6502 like CPU - the Z80 cpu mode is not supported)
 - "cx16": [CommanderX16](https://www.commanderx16.com)  (65c02 CPU)
+- "pet32": Commodore PET (experimental)
+- "atari": Atari 8 bit such as 800XL (experimental)
 - If you only use standard kernal and prog8 library routines, it is possible to compile the *exact same program* for different machines (just change the compiler target flag)
 
 
@@ -76,7 +101,9 @@ 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.

codeCore/build.gradle

@@ -26,16 +26,16 @@ compileTestKotlin {
 dependencies {
     // should have no dependencies to other modules
     implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8"
-    implementation "com.michael-bull.kotlin-result:kotlin-result-jvm:1.1.16"
+    implementation "com.michael-bull.kotlin-result:kotlin-result-jvm:1.1.18"
 }
 
 sourceSets {
     main {
         java {
-            srcDirs = ["${project.projectDir}/src"]
+            srcDir "${project.projectDir}/src"
         }
         resources {
-            srcDirs = ["${project.projectDir}/res"]
+            srcDir "${project.projectDir}/res"
         }
     }
 }

codeCore/src/prog8/code/SymbolTable.kt

@@ -1,5 +1,7 @@
 package prog8.code
 
+import prog8.code.ast.PtNode
+import prog8.code.ast.PtProgram
 import prog8.code.core.*
 
 
@@ -7,19 +9,32 @@ import prog8.code.core.*
  * Tree structure containing all symbol definitions in the program
  * (blocks, subroutines, variables (all types), memoryslabs, and labels).
  */
-class SymbolTable : StNode("", StNodeType.GLOBAL, Position.DUMMY) {
+class SymbolTable(astProgram: PtProgram) : StNode(astProgram.name, StNodeType.GLOBAL, astProgram) {
     /**
      * The table as a flat mapping of scoped names to the StNode.
      * This gives the fastest lookup possible (no need to traverse tree nodes)
      */
-    val flat: Map<List<String>, StNode> by lazy {
+
-        val result = mutableMapOf<List<String>, StNode>()
+    private var cachedFlat: Map<String, StNode>? = null
-        fun flatten(node: StNode) {
+
-            result[node.scopedName] = node
+    val flat: Map<String, StNode> get()  {
-            node.children.values.forEach { flatten(it) }
+        if(cachedFlat!=null)
+            return cachedFlat!!
+
+        val result = mutableMapOf<String, StNode>()
+        fun collect(node: StNode) {
+            for(child in node.children) {
+                result[child.value.scopedName] = child.value
+                collect(child.value)
+            }
         }
-        children.values.forEach { flatten(it) }
+        collect(this)
-        result
+        cachedFlat = result
+        return result
+    }
+
+    fun resetCachedFlat() {
+        cachedFlat = null
     }
 
     val allVariables: Collection<StStaticVariable> by lazy {
@@ -51,10 +66,30 @@ class SymbolTable : StNode("", StNodeType.GLOBAL, Position.DUMMY) {
     }
 
     val allMemorySlabs: Collection<StMemorySlab> by lazy {
-        children.mapNotNull { if (it.value.type == StNodeType.MEMORYSLAB) it.value as StMemorySlab else null }
+        val vars = mutableListOf<StMemorySlab>()
+        fun collect(node: StNode) {
+            for(child in node.children) {
+                if(child.value.type== StNodeType.MEMORYSLAB)
+                    vars.add(child.value as StMemorySlab)
+                else
+                    collect(child.value)
+            }
+        }
+        collect(this)
+        vars
     }
 
-    override fun lookup(scopedName: List<String>) = flat[scopedName]
+    override fun lookup(scopedName: String) = flat[scopedName]
+
+    fun getLength(name: String): Int? {
+        val node = flat[name]
+        return when(node) {
+            is StMemVar -> node.length
+            is StMemorySlab -> node.size.toInt()
+            is StStaticVariable -> node.length
+            else -> null
+        }
+    }
 }
 
 
@@ -75,44 +110,24 @@ enum class StNodeType {
 
 open class StNode(val name: String,
                   val type: StNodeType,
-                  val position: Position,
+                  val astNode: PtNode,
                   val children: MutableMap<String, StNode> = mutableMapOf()
 ) {
 
     lateinit var parent: StNode
 
-    val scopedName: List<String> by lazy {
+    val scopedName: String by lazy { scopedNameList.joinToString(".") }
-        if(type== StNodeType.GLOBAL)
-            emptyList()
-        else
-            parent.scopedName + name
-    }
 
-    fun lookup(name: String) =
+    open fun lookup(scopedName: String) =
-        lookupUnqualified(name)
+        lookup(scopedName.split('.'))
-    open fun lookup(scopedName: List<String>) =
-        if(scopedName.size>1) lookupQualified(scopedName) else lookupUnqualified(scopedName[0])
-    fun lookupOrElse(name: String, default: () -> StNode) =
-        lookupUnqualified(name) ?: default()
-    fun lookupOrElse(scopedName: List<String>, default: () -> StNode) =
-        lookup(scopedName) ?: default()
 
-    private fun lookupQualified(scopedName: List<String>): StNode? {
+    fun lookupUnscopedOrElse(name: String, default: () -> StNode) =
-        // a scoped name refers to a name in another namespace, and always stars from the root.
+        lookupUnscoped(name) ?: default()
-        var node = this
-        while(node.type!= StNodeType.GLOBAL)
-            node = node.parent
 
-        for(name in scopedName) {
+    fun lookupOrElse(scopedName: String, default: () -> StNode): StNode =
-            if(name in node.children)
+        lookup(scopedName.split('.')) ?: default()
-                node = node.children.getValue(name)
-            else
-                return null
-        }
-        return node
-    }
 
-    private fun lookupUnqualified(name: String): StNode? {
+    fun lookupUnscoped(name: String): StNode? {
         // first consider the builtin functions
         var globalscope = this
         while(globalscope.type!= StNodeType.GLOBAL)
@@ -138,37 +153,54 @@ open class StNode(val name: String,
         children[child.name] = child
         child.parent = this
     }
+
+    private val scopedNameList: List<String> by lazy {
+        if(type==StNodeType.GLOBAL)
+            emptyList()
+        else
+            parent.scopedNameList + name
+    }
+
+    private fun lookup(scopedName: List<String>): StNode? {
+        // a scoped name refers to a name in another namespace, and always stars from the root.
+        var node = this
+        while(node.type!=StNodeType.GLOBAL)
+            node = node.parent
+
+        for(name in scopedName) {
+            if(name in node.children)
+                node = node.children.getValue(name)
+            else
+                return null
+        }
+        return node
+    }
 }
 
 class StStaticVariable(name: String,
                        val dt: DataType,
-                       val bss: Boolean,
                        val onetimeInitializationNumericValue: Double?,      // regular (every-run-time) initialization is done via regular assignments
                        val onetimeInitializationStringValue: StString?,
                        val onetimeInitializationArrayValue: StArray?,
-                       val length: Int?,             // for arrays: the number of elements, for strings: number of characters *including* the terminating 0-byte
+                       val length: Int?,            // for arrays: the number of elements, for strings: number of characters *including* the terminating 0-byte
-                       val zpwish: ZeropageWish,
+                       val zpwish: ZeropageWish,    // used in the variable allocator
-                       position: Position) : StNode(name, StNodeType.STATICVAR, position) {
+                       astNode: PtNode) : StNode(name, StNodeType.STATICVAR, astNode) {
+
+    val uninitialized = onetimeInitializationArrayValue==null && onetimeInitializationStringValue==null && onetimeInitializationNumericValue==null
 
     init {
-        if(bss) {
-            require(onetimeInitializationNumericValue==null)
-            require(onetimeInitializationStringValue==null)
-            require(onetimeInitializationArrayValue.isNullOrEmpty())
-        } else {
-            require(onetimeInitializationNumericValue!=null ||
-                    onetimeInitializationStringValue!=null ||
-                    onetimeInitializationArrayValue!=null)
-        }
         if(length!=null) {
             require(onetimeInitializationNumericValue == null)
             if(onetimeInitializationArrayValue!=null)
                 require(onetimeInitializationArrayValue.isEmpty() ||onetimeInitializationArrayValue.size==length)
         }
-        if(onetimeInitializationNumericValue!=null)
+        if(onetimeInitializationNumericValue!=null) {
             require(dt in NumericDatatypes)
-        if(onetimeInitializationArrayValue!=null)
+        }
+        if(onetimeInitializationArrayValue!=null) {
             require(dt in ArrayDatatypes)
+            require(length==onetimeInitializationArrayValue.size)
+        }
         if(onetimeInitializationStringValue!=null) {
             require(dt == DataType.STR)
             require(length == onetimeInitializationStringValue.first.length+1)
@@ -177,45 +209,48 @@ class StStaticVariable(name: String,
 }
 
 
-class StConstant(name: String, val dt: DataType, val value: Double, position: Position) :
+class StConstant(name: String, val dt: DataType, val value: Double, astNode: PtNode) :
-    StNode(name, StNodeType.CONSTANT, position) {
+    StNode(name, StNodeType.CONSTANT, astNode)
-}
 
 
 class StMemVar(name: String,
                val dt: DataType,
                val address: UInt,
                val length: Int?,             // for arrays: the number of elements, for strings: number of characters *including* the terminating 0-byte
-               position: Position) :
+               astNode: PtNode) :
-    StNode(name, StNodeType.MEMVAR, position) {
+    StNode(name, StNodeType.MEMVAR, astNode) {
+
+    init{
+        if(dt in ArrayDatatypes || dt == DataType.STR)
+            require(length!=null) { "memory mapped array or string must have known length" }
+    }
 }
 
 class StMemorySlab(
     name: String,
     val size: UInt,
     val align: UInt,
-    position: Position
+    astNode: PtNode
 ):
-    StNode(name, StNodeType.MEMORYSLAB, position) {
+    StNode(name, StNodeType.MEMORYSLAB, astNode)
-}
 
-class StSub(name: String, val parameters: List<StSubroutineParameter>, val returnType: DataType?, position: Position) :
+
-        StNode(name, StNodeType.SUBROUTINE, position) {
+class StSub(name: String, val parameters: List<StSubroutineParameter>, val returnType: DataType?, astNode: PtNode) :
-}
+        StNode(name, StNodeType.SUBROUTINE, astNode)
 
 
 class StRomSub(name: String,
-               val address: UInt,
+               val address: UInt?,      // null in case of asmsub, specified in case of romsub
                val parameters: List<StRomSubParameter>,
-               val returns: List<RegisterOrStatusflag>,
+               val returns: List<StRomSubParameter>,
-               position: Position) :
+               astNode: PtNode) :
-    StNode(name, StNodeType.ROMSUB, position) {
+    StNode(name, StNodeType.ROMSUB, astNode)
-}
+
 
 
 class StSubroutineParameter(val name: String, val type: DataType)
 class StRomSubParameter(val register: RegisterOrStatusflag, val type: DataType)
-class StArrayElement(val number: Double?, val addressOf: List<String>?)
+class StArrayElement(val number: Double?, val addressOfSymbol: String?)
 
 typealias StString = Pair<String, Encoding>
 typealias StArray = List<StArrayElement>

codeCore/src/prog8/code/SymbolTableMaker.kt

@@ -0,0 +1,206 @@
+package prog8.code
+
+import prog8.code.ast.*
+import prog8.code.core.*
+import prog8.code.target.VMTarget
+import java.util.*
+
+class SymbolTableMaker(private val program: PtProgram, private val options: CompilationOptions) {
+    fun make(): SymbolTable {
+        val st = SymbolTable(program)
+
+        BuiltinFunctions.forEach {
+            st.add(StNode(it.key, StNodeType.BUILTINFUNC, PtIdentifier(it.key, it.value.returnType ?: DataType.UNDEFINED, Position.DUMMY)))
+        }
+
+        val scopestack = Stack<StNode>()
+        scopestack.push(st)
+        program.children.forEach {
+            addToSt(it, scopestack)
+        }
+        require(scopestack.size==1)
+
+        if(options.compTarget.name != VMTarget.NAME) {
+            listOf(
+                PtMemMapped("P8ZP_SCRATCH_B1", DataType.UBYTE, options.compTarget.machine.zeropage.SCRATCH_B1, null, Position.DUMMY),
+                PtMemMapped("P8ZP_SCRATCH_REG", DataType.UBYTE, options.compTarget.machine.zeropage.SCRATCH_REG, null, Position.DUMMY),
+                PtMemMapped("P8ZP_SCRATCH_W1", DataType.UWORD, options.compTarget.machine.zeropage.SCRATCH_W1, null, Position.DUMMY),
+                PtMemMapped("P8ZP_SCRATCH_W2", DataType.UWORD, options.compTarget.machine.zeropage.SCRATCH_W2, null, Position.DUMMY),
+            ).forEach {
+                it.parent = program
+                st.add(StMemVar(it.name, it.type, it.address, it.arraySize?.toInt(), it))
+            }
+        }
+
+        return st
+    }
+
+    private fun addToSt(node: PtNode, scope: Stack<StNode>) {
+        val stNode = when(node) {
+            is PtAsmSub -> {
+                val parameters = node.parameters.map { StRomSubParameter(it.first, it.second.type) }
+                val returns = node.returns.map { StRomSubParameter(it.first, it.second) }
+                StRomSub(node.name, node.address, parameters, returns, node)
+            }
+            is PtBlock -> {
+                StNode(node.name, StNodeType.BLOCK, node)
+            }
+            is PtConstant -> {
+                StConstant(node.name, node.type, node.value, node)
+            }
+            is PtLabel -> {
+                StNode(node.name, StNodeType.LABEL, node)
+            }
+            is PtMemMapped -> {
+                StMemVar(node.name, node.type, node.address, node.arraySize?.toInt(), node)
+            }
+            is PtSub -> {
+                val params = node.parameters.map {StSubroutineParameter(it.name, it.type) }
+                StSub(node.name, params, node.returntype, node)
+            }
+            is PtVariable -> {
+                val initialNumeric: Double?
+                val initialString: StString?
+                val initialArray: StArray?
+                val numElements: Int?
+                val value = node.value
+                if(value!=null) {
+                    val number = (value as? PtNumber)?.number
+                    initialNumeric = if(number==0.0) null else number       // 0 as init value -> just uninitialized
+                    when (value) {
+                        is PtString -> {
+                            initialString = StString(value.value, value.encoding)
+                            initialArray = null
+                            numElements = value.value.length + 1   // include the terminating 0-byte
+                        }
+                        is PtArray -> {
+                            initialArray = makeInitialArray(value)
+                            initialString = null
+                            numElements = initialArray.size
+                            require(node.arraySize?.toInt()==numElements)
+                        }
+                        else -> {
+                            initialString = null
+                            initialArray = null
+                            numElements = node.arraySize?.toInt()
+                        }
+                    }
+                } else {
+                    initialNumeric = null
+                    initialArray = null
+                    initialString = null
+                    numElements = node.arraySize?.toInt()
+                }
+//                if(node.type in SplitWordArrayTypes) {
+//                    ... split array also add _lsb and _msb to symboltable?
+//                }
+                StStaticVariable(node.name, node.type, initialNumeric, initialString, initialArray, numElements, node.zeropage, node)
+            }
+            is PtBuiltinFunctionCall -> {
+                if(node.name=="memory") {
+                    // memory slab allocations are a builtin functioncall in the program, but end up named as well in the symboltable
+                    require(node.name.all { it.isLetterOrDigit() || it=='_' }) {"memory name should be a valid symbol name"}
+                    val slabname = (node.args[0] as PtString).value
+                    val size = (node.args[1] as PtNumber).number.toUInt()
+                    val align = (node.args[2] as PtNumber).number.toUInt()
+                    // don't add memory slabs in nested scope, just put them in the top level of the ST
+                    scope.firstElement().add(StMemorySlab("prog8_memoryslab_$slabname", size, align, node))
+                }
+                null
+            }
+            else -> null // node is not present in the ST
+        }
+
+        if(stNode!=null) {
+            scope.peek().add(stNode)
+            scope.push(stNode)
+        }
+        node.children.forEach {
+            addToSt(it, scope)
+        }
+        if(stNode!=null)
+            scope.pop()
+    }
+
+    private fun makeInitialArray(value: PtArray): List<StArrayElement> {
+        return value.children.map {
+            when(it) {
+                is PtAddressOf -> {
+                    if(it.isFromArrayElement)
+                        TODO("address-of array element $it in initial array value")
+                    StArrayElement(null, it.identifier.name)
+                }
+                is PtIdentifier -> StArrayElement(null, it.name)
+                is PtNumber -> StArrayElement(it.number, null)
+                else -> throw AssemblyError("invalid array element $it")
+            }
+        }
+    }
+
+}
+
+//    override fun visit(decl: VarDecl) {
+//        val node =
+//            when(decl.type) {
+//                VarDeclType.VAR -> {
+//                    var initialNumeric = (decl.value as? NumericLiteral)?.number
+//                    if(initialNumeric==0.0)
+//                        initialNumeric=null     // variable will go into BSS and this will be set to 0
+//                    val initialStringLit = decl.value as? StringLiteral
+//                    val initialString = if(initialStringLit==null) null else Pair(initialStringLit.value, initialStringLit.encoding)
+//                    val initialArrayLit = decl.value as? ArrayLiteral
+//                    val initialArray = makeInitialArray(initialArrayLit)
+//                    if(decl.isArray && decl.datatype !in ArrayDatatypes)
+//                        throw FatalAstException("array vardecl has mismatched dt ${decl.datatype}")
+//                    val numElements =
+//                        if(decl.isArray)
+//                            decl.arraysize!!.constIndex()
+//                        else if(initialStringLit!=null)
+//                            initialStringLit.value.length+1  // include the terminating 0-byte
+//                        else
+//                            null
+//                    val bss = if(decl.datatype==DataType.STR)
+//                        false
+//                    else if(decl.isArray)
+//                        initialArray.isNullOrEmpty()
+//                    else
+//                        initialNumeric == null
+//                    val astNode = PtVariable(decl.name, decl.datatype, null, null, decl.position)
+//                    StStaticVariable(decl.name, decl.datatype, bss, initialNumeric, initialString, initialArray, numElements, decl.zeropage, astNode, decl.position)
+//                }
+//                VarDeclType.CONST -> {
+//                    val astNode = PtVariable(decl.name, decl.datatype, null, null, decl.position)
+//                    StConstant(decl.name, decl.datatype, (decl.value as NumericLiteral).number, astNode, decl.position)
+//                }
+//                VarDeclType.MEMORY -> {
+//                    val numElements =
+//                        if(decl.isArray)
+//                            decl.arraysize!!.constIndex()
+//                        else null
+//                    val astNode = PtVariable(decl.name, decl.datatype, null, null, decl.position)
+//                    StMemVar(decl.name, decl.datatype, (decl.value as NumericLiteral).number.toUInt(), numElements, astNode, decl.position)
+//                }
+//            }
+//        scopestack.peek().add(node)
+//        // st.origAstLinks[decl] = node
+//    }
+//
+//    private fun makeInitialArray(arrayLit: ArrayLiteral?): StArray? {
+//        if(arrayLit==null)
+//            return null
+//        return arrayLit.value.map {
+//            when(it){
+//                is AddressOf -> {
+//                    val scopedName = it.identifier.targetNameAndType(program).first
+//                    StArrayElement(null, scopedName)
+//                }
+//                is IdentifierReference -> {
+//                    val scopedName = it.targetNameAndType(program).first
+//                    StArrayElement(null, scopedName)
+//                }
+//                is NumericLiteral -> StArrayElement(it.number, null)
+//                else -> throw FatalAstException("weird element dt in array literal")
+//            }
+//        }.toList()
+//    }
+//

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

@@ -1,6 +1,9 @@
 package prog8.code.ast
 
-import prog8.code.core.*
+import prog8.code.core.IMemSizer
+import prog8.code.core.IStringEncoding
+import prog8.code.core.Position
+import prog8.code.core.SourceCode
 import java.nio.file.Path
 
 // New simplified AST for the code generator.
@@ -11,16 +14,6 @@ sealed class PtNode(val position: Position) {
     val children = mutableListOf<PtNode>()
     lateinit var parent: PtNode
 
-    fun printIndented(indent: Int) {
-        print("    ".repeat(indent))
-        print("${this.javaClass.simpleName}  ")
-        printProperties()
-        println()
-        children.forEach { it.printIndented(indent+1) }
-    }
-
-    abstract fun printProperties()
-
     fun add(child: PtNode) {
         children.add(child)
         child.parent = this
@@ -34,25 +27,30 @@ sealed class PtNode(val position: Position) {
     fun definingBlock() = findParentNode<PtBlock>(this)
     fun definingSub() = findParentNode<PtSub>(this)
     fun definingAsmSub() = findParentNode<PtAsmSub>(this)
+    fun definingISub() = findParentNode<IPtSubroutine>(this)
 }
 
 
-class PtNodeGroup : PtNode(Position.DUMMY) {
+sealed interface IPtStatementContainer
-    override fun printProperties() {}
-}
 
 
-sealed class PtNamedNode(val name: String, position: Position): PtNode(position) {
+class PtNodeGroup : PtNode(Position.DUMMY), IPtStatementContainer
-    val scopedName: List<String> by lazy {
+
-        var namedParent: PtNode = this.parent
+
-        if(namedParent is PtProgram)
+sealed class PtNamedNode(var name: String, position: Position): PtNode(position) {
-            listOf(name)
+    // Note that as an exception, the 'name' is not read-only
-        else {
+    // but a var. This is to allow for cheap node renames.
-            while (namedParent !is PtNamedNode)
+    val scopedName: String
-                namedParent = namedParent.parent
+        get() {
-            namedParent.scopedName + name
+            var namedParent: PtNode = this.parent
+            return if(namedParent is PtProgram)
+                name
+            else {
+                while (namedParent !is PtNamedNode)
+                    namedParent = namedParent.parent
+                namedParent.scopedName + "." + name
+            }
         }
-    }
 }
 
 
@@ -61,10 +59,6 @@ class PtProgram(
     val memsizer: IMemSizer,
     val encoding: IStringEncoding
 ) : PtNode(Position.DUMMY) {
-    fun print() = printIndented(0)
-    override fun printProperties() {
-        print("'$name'")
-    }
 
 //    fun allModuleDirectives(): Sequence<PtDirective> =
 //        children.asSequence().flatMap { it.children }.filterIsInstance<PtDirective>().distinct()
@@ -73,32 +67,34 @@ class PtProgram(
         children.asSequence().filterIsInstance<PtBlock>()
 
     fun entrypoint(): PtSub? =
-        allBlocks().firstOrNull { it.name == "main" }?.children?.firstOrNull { it is PtSub && it.name == "start" } as PtSub?
+        allBlocks().firstOrNull { it.name == "main" || it.name=="p8b_main" }
+            ?.children
+            ?.firstOrNull { it is PtSub && (it.name == "start" || it.name=="main.start" || it.name=="p8s_start" || it.name=="p8b_main.p8s_start") } as PtSub?
 }
 
 
 class PtBlock(name: String,
-              val address: UInt?,
               val library: Boolean,
-              val forceOutput: Boolean,
+              val source: SourceCode,       // taken from the module the block is defined in.
-              val alignment: BlockAlignment,
+              val options: Options,
               position: Position
-) : PtNamedNode(name, position) {
+) : PtNamedNode(name, position), IPtStatementContainer {
-    override fun printProperties() {
-        print("$name  addr=$address  library=$library  forceOutput=$forceOutput  alignment=$alignment")
-    }
-
     enum class BlockAlignment {
         NONE,
         WORD,
         PAGE
     }
+
+    class Options(val address: UInt? = null,
+                  val forceOutput: Boolean = false,
+                  val noSymbolPrefixing: Boolean = false,
+                  val veraFxMuls: Boolean = false,
+                  val ignoreUnused: Boolean = false,
+                  val alignment: BlockAlignment = BlockAlignment.NONE)
 }
 
 
 class PtInlineAssembly(val assembly: String, val isIR: Boolean, position: Position) : PtNode(position) {
-    override fun printProperties() {}
-
     init {
         require(!assembly.startsWith('\n') && !assembly.startsWith('\r')) { "inline assembly should be trimmed" }
         require(!assembly.endsWith('\n') && !assembly.endsWith('\r')) { "inline assembly should be trimmed" }
@@ -106,34 +102,16 @@ class PtInlineAssembly(val assembly: String, val isIR: Boolean, position: Positi
 }
 
 
-class PtLabel(name: String, position: Position) : PtNamedNode(name, position) {
+class PtLabel(name: String, position: Position) : PtNamedNode(name, position)
-    override fun printProperties() {
-        print(name)
-    }
-}
 
 
-class PtBreakpoint(position: Position): PtNode(position) {
+class PtBreakpoint(position: Position): PtNode(position)
-    override fun printProperties() {}
-}
 
 
-class PtIncludeBinary(val file: Path, val offset: UInt?, val length: UInt?, position: Position) : PtNode(position) {
+class PtIncludeBinary(val file: Path, val offset: UInt?, val length: UInt?, position: Position) : PtNode(position)
-    override fun printProperties() {
-        print("filename=$file  offset=$offset  length=$length")
-    }
-}
 
 
-class PtNop(position: Position): PtNode(position) {
+class PtNop(position: Position): PtNode(position)
-    override fun printProperties() {}
-}
-
-
-class PtScopeVarsDecls(position: Position): PtNode(position) {
-    override fun printProperties() {}
-}
-
 
 
 // find the parent node of a specific type or interface

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

@@ -1,10 +1,9 @@
 package prog8.code.ast
 
-import prog8.code.core.DataType
+import prog8.code.core.*
-import prog8.code.core.Encoding
-import prog8.code.core.Position
 import java.util.*
-import kotlin.math.round
+import kotlin.math.abs
+import kotlin.math.truncate
 
 
 sealed class PtExpression(val type: DataType, position: Position) : PtNode(position) {
@@ -23,17 +22,30 @@ sealed class PtExpression(val type: DataType, position: Position) : PtNode(posit
         }
     }
 
-    override fun printProperties() {
-        print(type)
-    }
-
     infix fun isSameAs(other: PtExpression): Boolean {
         return when(this) {
-            is PtAddressOf -> other is PtAddressOf && other.type==type && other.identifier isSameAs identifier
+            is PtAddressOf -> {
-            is PtArrayIndexer -> other is PtArrayIndexer && other.type==type && other.variable isSameAs variable && other.index isSameAs index
+                if(other !is PtAddressOf)
-            is PtBinaryExpression -> other is PtBinaryExpression && other.left isSameAs left && other.right isSameAs right
+                    return false
+                if (other.type!==type || !(other.identifier isSameAs identifier))
+                    return false
+                if(other.children.size!=children.size)
+                    return false
+                if(children.size==1)
+                    return true
+                return arrayIndexExpr!! isSameAs other.arrayIndexExpr!!
+            }
+            is PtArrayIndexer -> other is PtArrayIndexer && other.type==type && other.variable isSameAs variable && other.index isSameAs index && other.splitWords==splitWords
+            is PtBinaryExpression -> {
+                if(other !is PtBinaryExpression || other.operator!=operator)
+                    false
+                else if(operator in AssociativeOperators)
+                    (other.left isSameAs left && other.right isSameAs right) || (other.left isSameAs right && other.right isSameAs left)
+                else
+                    other.left isSameAs left && other.right isSameAs right
+            }
             is PtContainmentCheck -> other is PtContainmentCheck && other.type==type && other.element isSameAs element && other.iterable isSameAs iterable
-            is PtIdentifier -> other is PtIdentifier && other.type==type && other.targetName==targetName
+            is PtIdentifier -> other is PtIdentifier && other.type==type && other.name==name
             is PtMachineRegister -> other is PtMachineRegister && other.type==type && other.register==register
             is PtMemoryByte -> other is PtMemoryByte && other.address isSameAs address
             is PtNumber -> other is PtNumber && other.type==type && other.number==number
@@ -43,19 +55,102 @@ sealed class PtExpression(val type: DataType, position: Position) : PtNode(posit
             else -> false
         }
     }
+
+    infix fun isSameAs(target: PtAssignTarget): Boolean {
+        return when {
+            target.memory != null && this is PtMemoryByte-> {
+                target.memory!!.address isSameAs this.address
+            }
+            target.identifier != null && this is PtIdentifier -> {
+                this.name == target.identifier!!.name
+            }
+            target.array != null && this is PtArrayIndexer -> {
+                this.variable.name == target.array!!.variable.name && this.index isSameAs target.array!!.index && this.splitWords==target.array!!.splitWords
+            }
+            else -> false
+        }
+    }
+
+    fun asConstInteger(): Int? = (this as? PtNumber)?.number?.toInt()
+
+    fun isSimple(): Boolean {
+        return when(this) {
+            is PtAddressOf -> true
+            is PtArray -> true
+            is PtArrayIndexer -> index is PtNumber || index is PtIdentifier
+            is PtBinaryExpression -> false
+            is PtBuiltinFunctionCall -> {
+                when (name) {
+                    in arrayOf("msb", "lsb", "mkword", "set_carry", "set_irqd", "clear_carry", "clear_irqd") -> this.args.all { it.isSimple() }
+                    else -> false
+                }
+            }
+            is PtContainmentCheck -> false
+            is PtFunctionCall -> false
+            is PtIdentifier -> true
+            is PtMachineRegister -> true
+            is PtMemoryByte -> address is PtNumber || address is PtIdentifier
+            is PtNumber -> true
+            is PtPrefix -> value.isSimple()
+            is PtRange -> true
+            is PtString -> true
+            is PtTypeCast -> value.isSimple()
+        }
+    }
+
+    /*
+    fun clone(): PtExpression {
+        fun withClonedChildrenFrom(orig: PtExpression, clone: PtExpression): PtExpression {
+            orig.children.forEach { clone.add((it as PtExpression).clone()) }
+            return clone
+        }
+        when(this) {
+            is PtAddressOf -> return withClonedChildrenFrom(this, PtAddressOf(position))
+            is PtArray -> return withClonedChildrenFrom(this, PtArray(type, position))
+            is PtArrayIndexer -> return withClonedChildrenFrom(this, PtArrayIndexer(type, position))
+            is PtBinaryExpression -> return withClonedChildrenFrom(this, PtBinaryExpression(operator, type, position))
+            is PtBuiltinFunctionCall -> return withClonedChildrenFrom(this, PtBuiltinFunctionCall(name, void, hasNoSideEffects, type, position))
+            is PtContainmentCheck -> return withClonedChildrenFrom(this, PtContainmentCheck(position))
+            is PtFunctionCall -> return withClonedChildrenFrom(this, PtFunctionCall(name, void, type, position))
+            is PtIdentifier -> return withClonedChildrenFrom(this, PtIdentifier(name, type, position))
+            is PtMachineRegister -> return withClonedChildrenFrom(this, PtMachineRegister(register, type, position))
+            is PtMemoryByte -> return withClonedChildrenFrom(this, PtMemoryByte(position))
+            is PtNumber -> return withClonedChildrenFrom(this, PtNumber(type, number, position))
+            is PtPrefix -> return withClonedChildrenFrom(this, PtPrefix(operator, type, position))
+            is PtRange -> return withClonedChildrenFrom(this, PtRange(type, position))
+            is PtString -> return withClonedChildrenFrom(this, PtString(value, encoding, position))
+            is PtTypeCast -> return withClonedChildrenFrom(this, PtTypeCast(type, position))
+        }
+    }
+    */
 }
 
 class PtAddressOf(position: Position) : PtExpression(DataType.UWORD, position) {
     val identifier: PtIdentifier
-        get() = children.single() as PtIdentifier
+        get() = children[0] as PtIdentifier
+    val arrayIndexExpr: PtExpression?
+        get() = if(children.size==2) children[1] as PtExpression else null
+
+    val isFromArrayElement: Boolean
+        get() = children.size==2
 }
 
 
-class PtArrayIndexer(type: DataType, position: Position): PtExpression(type, position) {
+class PtArrayIndexer(elementType: DataType, position: Position): PtExpression(elementType, position) {
     val variable: PtIdentifier
         get() = children[0] as PtIdentifier
     val index: PtExpression
         get() = children[1] as PtExpression
+
+    val splitWords: Boolean
+        get() = variable.type in SplitWordArrayTypes
+
+    val usesPointerVariable: Boolean
+        get() = variable.type==DataType.UWORD
+
+    init {
+        require(elementType in NumericDatatypes)
+    }
 }
 
 
@@ -66,6 +161,9 @@ class PtArray(type: DataType, position: Position): PtExpression(type, position)
             return false
         return type==other.type && children == other.children
     }
+
+    val size: Int
+        get() = children.size
 }
 
 
@@ -81,9 +179,6 @@ class PtBuiltinFunctionCall(val name: String,
 
     val args: List<PtExpression>
         get() = children.map { it as PtExpression }
-    override fun printProperties() {
-        print("$name void=$void noSideFx=$hasNoSideEffects")
-    }
 }
 
 
@@ -93,10 +188,6 @@ class PtBinaryExpression(val operator: String, type: DataType, position: Positio
         get() = children[0] as PtExpression
     val right: PtExpression
         get() = children[1] as PtExpression
-
-    override fun printProperties() {
-        print("$operator -> $type")
-    }
 }
 
 
@@ -108,7 +199,7 @@ class PtContainmentCheck(position: Position): PtExpression(DataType.UBYTE, posit
 }
 
 
-class PtFunctionCall(val functionName: List<String>,
+class PtFunctionCall(val name: String,
                      val void: Boolean,
                      type: DataType,
                      position: Position) : PtExpression(type, position) {
@@ -119,42 +210,41 @@ class PtFunctionCall(val functionName: List<String>,
 
     val args: List<PtExpression>
         get() = children.map { it as PtExpression }
-    override fun printProperties() {
-        print("${functionName.joinToString(".")} void=$void")
-    }
 }
 
 
-class PtIdentifier(val ref: List<String>, val targetName: List<String>, type: DataType, position: Position) : PtExpression(type, position) {
+class PtIdentifier(val name: String, type: DataType, position: Position) : PtExpression(type, position) {
-    override fun printProperties() {
+    override fun toString(): String {
-        print("$ref --> $targetName  $type")
+        return "[PtIdentifier:$name $type $position]"
     }
+
+    fun copy() = PtIdentifier(name, type, position)
 }
 
 
 class PtMemoryByte(position: Position) : PtExpression(DataType.UBYTE, position) {
     val address: PtExpression
         get() = children.single() as PtExpression
-    override fun printProperties() {}
 }
 
 
 class PtNumber(type: DataType, val number: Double, position: Position) : PtExpression(type, position) {
 
+    companion object {
+        fun fromBoolean(bool: Boolean, position: Position): PtNumber =
+            PtNumber(DataType.UBYTE, if(bool) 1.0 else 0.0, position)
+    }
+
     init {
         if(type==DataType.BOOL)
             throw IllegalArgumentException("bool should have become ubyte @$position")
         if(type!=DataType.FLOAT) {
-            val rounded = round(number)
+            val trunc = truncate(number)
-            if (rounded != number)
+            if (trunc != number)
-                throw IllegalArgumentException("refused rounding of float to avoid loss of precision @$position")
+                throw IllegalArgumentException("refused truncating of float to avoid loss of precision @$position")
         }
     }
 
-    override fun printProperties() {
-        print("$number ($type)")
-    }
-
     override fun hashCode(): Int = Objects.hash(type, number)
 
     override fun equals(other: Any?): Boolean {
@@ -164,6 +254,8 @@ class PtNumber(type: DataType, val number: Double, position: Position) : PtExpre
     }
 
     operator fun compareTo(other: PtNumber): Int = number.compareTo(other.number)
+
+    override fun toString() = "PtNumber:$type:$number"
 }
 
 
@@ -175,10 +267,6 @@ class PtPrefix(val operator: String, type: DataType, position: Position): PtExpr
         // note: the "not" operator may no longer occur in the ast; not x should have been replaced with x==0
         require(operator in setOf("+", "-", "~")) { "invalid prefix operator: $operator" }
     }
-
-    override fun printProperties() {
-        print(operator)
-    }
 }
 
 
@@ -190,15 +278,36 @@ class PtRange(type: DataType, position: Position) : PtExpression(type, position)
     val step: PtNumber
         get() = children[2] as PtNumber
 
-    override fun printProperties() {}
+    fun toConstantIntegerRange(): IntProgression? {
+        fun makeRange(fromVal: Int, toVal: Int, stepVal: Int): IntProgression {
+            return when {
+                fromVal <= toVal -> when {
+                    stepVal <= 0 -> IntRange.EMPTY
+                    stepVal == 1 -> fromVal..toVal
+                    else -> fromVal..toVal step stepVal
+                }
+                else -> when {
+                    stepVal >= 0 -> IntRange.EMPTY
+                    stepVal == -1 -> fromVal downTo toVal
+                    else -> fromVal downTo toVal step abs(stepVal)
+                }
+            }
+        }
+
+        val fromLv = from as? PtNumber
+        val toLv = to as? PtNumber
+        val stepLv = step as? PtNumber
+        if(fromLv==null || toLv==null || stepLv==null)
+            return null
+        val fromVal = fromLv.number.toInt()
+        val toVal = toLv.number.toInt()
+        val stepVal = stepLv.number.toInt()
+        return makeRange(fromVal, toVal, stepVal)
+    }
 }
 
 
 class PtString(val value: String, val encoding: Encoding, position: Position) : PtExpression(DataType.STR, position) {
-    override fun printProperties() {
-        print("$encoding:\"$value\"")
-    }
-
     override fun hashCode(): Int = Objects.hash(value, encoding)
     override fun equals(other: Any?): Boolean {
         if(other==null || other !is PtString)
@@ -214,12 +323,8 @@ class PtTypeCast(type: DataType, position: Position) : PtExpression(type, positi
 }
 
 
-// special node that isn't created from compiling user code, but used internally
+// special node that isn't created from compiling user code, but used internally in the Intermediate Code
-class PtMachineRegister(val register: Int, type: DataType, position: Position) : PtExpression(type, position) {
+class PtMachineRegister(val register: Int, type: DataType, position: Position) : PtExpression(type, position)
-    override fun printProperties() {
-        print("reg=$register  $type")
-    }
-}
 
 
 fun constValue(expr: PtExpression): Double? = if(expr is PtNumber) expr.number else null

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

@@ -0,0 +1,172 @@
+package prog8.code.ast
+
+import prog8.code.core.*
+
+/**
+ * Produces readable text from a [PtNode] (AST node, usually starting with PtProgram as root),
+ * passing it as a String to the specified receiver function.
+ */
+fun printAst(root: PtNode, skipLibraries: Boolean, output: (text: String) -> Unit) {
+    fun type(dt: DataType) = "!${dt.name.lowercase()}!"
+    fun txt(node: PtNode): String {
+        return when(node) {
+            is PtAssignTarget -> "<target>"
+            is PtAssignment -> "<assign>"
+            is PtAugmentedAssign -> "<inplace-assign> ${node.operator}"
+            is PtBreakpoint -> "%breakpoint"
+            is PtConditionalBranch -> "if_${node.condition.name.lowercase()}"
+            is PtAddressOf -> "&"
+            is PtArray -> "array len=${node.children.size} ${type(node.type)}"
+            is PtArrayIndexer -> "<arrayindexer> ${type(node.type)} ${if(node.splitWords) "[splitwords]" else ""}"
+            is PtBinaryExpression -> "<expr> ${node.operator} ${type(node.type)}"
+            is PtBuiltinFunctionCall -> {
+                val str = if(node.void) "void " else ""
+                str + node.name + "()"
+            }
+            is PtContainmentCheck -> "in"
+            is PtFunctionCall -> {
+                val str = if(node.void) "void " else ""
+                str + node.name + "()"
+            }
+            is PtIdentifier -> "${node.name} ${type(node.type)}"
+            is PtMachineRegister -> "VMREG#${node.register} ${type(node.type)}"
+            is PtMemoryByte -> "@()"
+            is PtNumber -> {
+                val numstr = if(node.type == DataType.FLOAT) node.number.toString() else node.number.toHex()
+                "$numstr ${type(node.type)}"
+            }
+            is PtPrefix -> node.operator
+            is PtRange -> "<range>"
+            is PtString -> "\"${node.value.escape()}\""
+            is PtTypeCast -> "as ${node.type.name.lowercase()}"
+            is PtForLoop -> "for"
+            is PtIfElse -> "ifelse"
+            is PtIncludeBinary -> "%incbin '${node.file}', ${node.offset}, ${node.length}"
+            is PtInlineAssembly -> {
+                if(node.isIR)
+                    "%ir {{ ...${node.assembly.length} characters... }}"
+                else
+                    "%asm {{ ...${node.assembly.length} characters... }}"
+            }
+            is PtJump -> {
+                if(node.identifier!=null)
+                    "goto ${node.identifier.name}"
+                else if(node.address!=null)
+                    "goto ${node.address.toHex()}"
+                else
+                    "???"
+            }
+            is PtAsmSub -> {
+                val params = node.parameters.map {
+                                val register = it.first.registerOrPair
+                                val statusflag = it.first.statusflag
+                                "${it.second.type} ${it.second.name} @${register ?: statusflag}"
+                            }.joinToString(", ")
+                val clobbers = if (node.clobbers.isEmpty()) "" else "clobbers ${node.clobbers}"
+                val returns = if (node.returns.isEmpty()) "" else {
+                    "-> ${node.returns.map {
+                        val register = it.first.registerOrPair
+                        val statusflag = it.first.statusflag
+                        "${it.second} @${register ?: statusflag}"}
+                        .joinToString(", ")
+                    }"
+                }
+                val str = if (node.inline) "inline " else ""
+                if(node.address==null) {
+                    str + "asmsub ${node.name}($params) $clobbers $returns"
+                } else {
+                    str + "romsub ${node.address.toHex()} = ${node.name}($params) $clobbers $returns"
+                }
+            }
+            is PtBlock -> {
+                val addr = if(node.options.address==null) "" else "@${node.options.address.toHex()}"
+                val align = if(node.options.alignment==PtBlock.BlockAlignment.NONE) "" else "align=${node.options.alignment}"
+                "\nblock '${node.name}' $addr $align"
+            }
+            is PtConstant -> {
+                val value = if(node.type in IntegerDatatypes) node.value.toInt().toString() else node.value.toString()
+                "const ${node.type.name.lowercase()} ${node.name} = $value"
+            }
+            is PtLabel -> "${node.name}:"
+            is PtMemMapped -> {
+                if(node.type in ArrayDatatypes) {
+                    val arraysize = if(node.arraySize==null) "" else node.arraySize.toString()
+                    val eltType = ArrayToElementTypes.getValue(node.type)
+                    "&${eltType.name.lowercase()}[$arraysize] ${node.name} = ${node.address.toHex()}"
+                } else {
+                    "&${node.type.name.lowercase()} ${node.name} = ${node.address.toHex()}"
+                }
+            }
+            is PtSub -> {
+                val params = node.parameters.map { "${it.type} ${it.name}" }.joinToString(", ")
+                var str = "sub ${node.name}($params) "
+                if(node.returntype!=null)
+                    str += "-> ${node.returntype.name.lowercase()}"
+                str
+            }
+            is PtVariable -> {
+                val split = if(node.type in SplitWordArrayTypes) "@split" else ""
+                val str = if(node.arraySize!=null) {
+                    val eltType = ArrayToElementTypes.getValue(node.type)
+                    "${eltType.name.lowercase()}[${node.arraySize}] $split ${node.name}"
+                }
+                else if(node.type in ArrayDatatypes) {
+                    val eltType = ArrayToElementTypes.getValue(node.type)
+                    "${eltType.name.lowercase()}[] $split ${node.name}"
+                }
+                else
+                    "${node.type.name.lowercase()} ${node.name}"
+                if(node.value!=null)
+                    str + " = " + txt(node.value)
+                else
+                    str
+            }
+            is PtNodeGroup -> "<group>"
+            is PtNop -> "nop"
+            is PtPostIncrDecr -> "<post> ${node.operator}"
+            is PtProgram -> "PROGRAM ${node.name}"
+            is PtRepeatLoop -> "repeat"
+            is PtReturn -> "return"
+            is PtSubroutineParameter -> "${node.type.name.lowercase()} ${node.name}"
+            is PtWhen -> "when"
+            is PtWhenChoice -> {
+                if(node.isElse)
+                    "else"
+                else
+                    "->"
+            }
+        }
+    }
+
+    if(root is PtProgram) {
+        output(txt(root))
+        root.children.forEach {
+            walkAst(it) { node, depth ->
+                val txt = txt(node)
+                val library = if(node is PtBlock) node.library else node.definingBlock()?.library==true
+                if(!library || !skipLibraries) {
+                    if (txt.isNotEmpty())
+                        output("    ".repeat(depth) + txt(node))
+                }
+            }
+        }
+        println()
+    } else {
+        walkAst(root) { node, depth ->
+            val txt = txt(node)
+            val library = if(node is PtBlock) node.library else node.definingBlock()?.library==true
+            if(!library || !skipLibraries) {
+                if (txt.isNotEmpty())
+                    output("    ".repeat(depth) + txt(node))
+            }
+        }
+    }
+}
+
+fun walkAst(root: PtNode, act: (node: PtNode, depth: Int) -> Unit) {
+    fun recurse(node: PtNode, depth: Int) {
+        act(node, depth)
+        node.children.forEach { recurse(it, depth+1) }
+    }
+    recurse(root, 0)
+}

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

@@ -3,87 +3,54 @@ package prog8.code.ast
 import prog8.code.core.*
 
 
+sealed interface IPtSubroutine {
+    val name: String
+}
+
 class PtAsmSub(
     name: String,
     val address: UInt?,
     val clobbers: Set<CpuRegister>,
-    val parameters: List<Pair<PtSubroutineParameter, RegisterOrStatusflag>>,
+    val parameters: List<Pair<RegisterOrStatusflag, PtSubroutineParameter>>,
-    val returnTypes: List<DataType>,    // TODO join with register as Pairs ?
+    val returns: List<Pair<RegisterOrStatusflag, DataType>>,
-    val retvalRegisters: List<RegisterOrStatusflag>,
     val inline: Boolean,
     position: Position
-) : PtNamedNode(name, position) {
+) : PtNamedNode(name, position), IPtSubroutine
-    override fun printProperties() {
-        print("$name  inline=$inline")
-    }
-}
 
 
 class PtSub(
     name: String,
     val parameters: List<PtSubroutineParameter>,
     val returntype: DataType?,
-    val inline: Boolean,
     position: Position
-) : PtNamedNode(name, position) {
+) : PtNamedNode(name, position), IPtSubroutine, IPtStatementContainer {
-    override fun printProperties() {
-        print(name)
-    }
-
     init {
         // params and return value should not be str
         if(parameters.any{ it.type !in NumericDatatypes })
             throw AssemblyError("non-numeric parameter")
         if(returntype!=null && returntype !in NumericDatatypes)
             throw AssemblyError("non-numeric returntype $returntype")
+        parameters.forEach { it.parent=this }
     }
 }
 
 
-class PtSubroutineParameter(val name: String, val type: DataType, position: Position): PtNode(position) {
+class PtSubroutineParameter(name: String, val type: DataType, position: Position): PtNamedNode(name, position)
-    override fun printProperties() {
-        print("$type $name")
-    }
-}
 
 
-class PtAssignment(position: Position) : PtNode(position) {
+sealed interface IPtAssignment {
+    val children: MutableList<PtNode>
     val target: PtAssignTarget
         get() = children[0] as PtAssignTarget
     val value: PtExpression
         get() = children[1] as PtExpression
-
-    override fun printProperties() { }
-
-    val isInplaceAssign: Boolean by lazy {
-        val target = target.children.single() as PtExpression
-        when(val source = value) {
-            is PtArrayIndexer -> {
-                if(target is PtArrayIndexer && source.type==target.type) {
-                    if(target.variable isSameAs source.variable) {
-                        target.index isSameAs source.index
-                    }
-                }
-                false
-            }
-            is PtIdentifier -> target is PtIdentifier && target.type==source.type && target.targetName==source.targetName
-            is PtMachineRegister -> target is PtMachineRegister && target.register==source.register
-            is PtMemoryByte -> target is PtMemoryByte && target.address isSameAs source.address
-            is PtNumber -> target is PtNumber && target.type == source.type && target.number==source.number
-            is PtAddressOf -> target is PtAddressOf && target.identifier isSameAs source.identifier
-            is PtPrefix -> {
-                (target is PtPrefix && target.operator==source.operator && target.value isSameAs source.value)
-                        ||
-                (target is PtIdentifier && (source.value as? PtIdentifier)?.targetName==target.targetName)
-            }
-            is PtTypeCast -> target is PtTypeCast && target.type==source.type && target.value isSameAs source.value
-            is PtBinaryExpression ->
-                target isSameAs source.left
-            else -> false
-        }
-    }
 }
 
+class PtAssignment(position: Position) : PtNode(position), IPtAssignment
+
+class PtAugmentedAssign(val operator: String, position: Position) : PtNode(position), IPtAssignment
+
+
 class PtAssignTarget(position: Position) : PtNode(position) {
     val identifier: PtIdentifier?
         get() = children.single() as? PtIdentifier
@@ -102,7 +69,7 @@ class PtAssignTarget(position: Position) : PtNode(position) {
             }
         }
 
-    override fun printProperties() {}
+    infix fun isSameAs(expression: PtExpression): Boolean = expression.isSameAs(this)
 }
 
 
@@ -111,10 +78,6 @@ class PtConditionalBranch(val condition: BranchCondition, position: Position) :
         get() = children[0] as PtNodeGroup
     val falseScope: PtNodeGroup
         get() = children[1] as PtNodeGroup
-
-    override fun printProperties() {
-        print(condition)
-    }
 }
 
 
@@ -125,31 +88,24 @@ class PtForLoop(position: Position) : PtNode(position) {
         get() = children[1] as PtExpression
     val statements: PtNodeGroup
         get() = children[2] as PtNodeGroup
-
-    override fun printProperties() {}
 }
 
 
 class PtIfElse(position: Position) : PtNode(position) {
-    val condition: PtBinaryExpression
+    val condition: PtExpression
-        get() = children[0] as PtBinaryExpression
+        get() = children[0] as PtExpression
     val ifScope: PtNodeGroup
         get() = children[1] as PtNodeGroup
     val elseScope: PtNodeGroup
         get() = children[2] as PtNodeGroup
-
-    override fun printProperties() {}
 }
 
 
-class PtJump(val identifier: PtIdentifier?,
+class PtJump(val identifier: PtIdentifier?,     // note: even ad-hoc labels are wrapped as an Identifier to simplify code. Just use dummy type and position.
              val address: UInt?,
-             val generatedLabel: String?,
              position: Position) : PtNode(position) {
-    override fun printProperties() {
+    init {
-        identifier?.printProperties()
+        identifier?.let {it.parent = this }
-        if(address!=null) print(address.toHex())
-        if(generatedLabel!=null) print(generatedLabel)
     }
 }
 
@@ -157,10 +113,6 @@ class PtJump(val identifier: PtIdentifier?,
 class PtPostIncrDecr(val operator: String, position: Position) : PtNode(position) {
     val target: PtAssignTarget
         get() = children.single() as PtAssignTarget
-
-    override fun printProperties() {
-        print(operator)
-    }
 }
 
 
@@ -169,8 +121,6 @@ class PtRepeatLoop(position: Position) : PtNode(position) {
         get() = children[0] as PtExpression
     val statements: PtNodeGroup
         get() = children[1] as PtNodeGroup
-
-    override fun printProperties() {}
 }
 
 
@@ -183,30 +133,26 @@ class PtReturn(position: Position) : PtNode(position) {
             else
                 null
         }
-
-    override fun printProperties() {}
 }
 
 
-class PtVariable(name: String, val type: DataType, var value: PtExpression?, var arraySize: UInt?, position: Position) : PtNamedNode(name, position) {
+sealed interface IPtVariable {
-    override fun printProperties() {
+    val name: String
-        print("$type  $name")
+    val type: DataType
+}
+
+
+class PtVariable(name: String, override val type: DataType, val zeropage: ZeropageWish, val value: PtExpression?, val arraySize: UInt?, position: Position) : PtNamedNode(name, position), IPtVariable {
+    init {
+        value?.let {it.parent=this}
     }
 }
 
 
-class PtConstant(name: String, val type: DataType, val value: Double, position: Position) : PtNamedNode(name, position) {
+class PtConstant(name: String, override val type: DataType, val value: Double, position: Position) : PtNamedNode(name, position), IPtVariable
-    override fun printProperties() {
-        print("$type $name = $value")
-    }
-}
 
 
-class PtMemMapped(name: String, val type: DataType, val address: UInt, position: Position) : PtNamedNode(name, position) {
+class PtMemMapped(name: String, override val type: DataType, val address: UInt, val arraySize: UInt?, position: Position) : PtNamedNode(name, position), IPtVariable
-    override fun printProperties() {
-        print("&$type $name = ${address.toHex()}")
-    }
-}
 
 
 class PtWhen(position: Position) : PtNode(position) {
@@ -214,8 +160,6 @@ class PtWhen(position: Position) : PtNode(position) {
         get() = children[0] as PtExpression
     val choices: PtNodeGroup
         get() = children[1] as PtNodeGroup
-
-    override fun printProperties() {}
 }
 
 
@@ -224,5 +168,4 @@ class PtWhenChoice(val isElse: Boolean, position: Position) : PtNode(position) {
         get() = children[0] as PtNodeGroup
     val statements: PtNodeGroup
         get() = children[1] as PtNodeGroup
-    override fun printProperties() {}
 }

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

@@ -0,0 +1,135 @@
+package prog8.code.core
+
+class ReturnConvention(val dt: DataType?, val reg: RegisterOrPair?, val floatFac1: Boolean)
+class ParamConvention(val dt: DataType, 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!=null -> returns.reg.toString()
+                returns.floatFac1 -> "floatFAC1"
+                else -> "<no returnvalue>"
+            }
+        return "CallConvention[" + paramConvs.joinToString() + " ; returns: $returnConv]"
+    }
+}
+
+class FParam(val name: String, val possibleDatatypes: Array<DataType>)
+
+class FSignature(val pure: Boolean,      // does it have side effects?
+                      val parameters: List<FParam>,
+                      val returnType: DataType?) {
+
+    fun callConvention(actualParamTypes: List<DataType>): CallConvention {
+        val returns: ReturnConvention = when (returnType) {
+            DataType.UBYTE, DataType.BYTE -> ReturnConvention(returnType, RegisterOrPair.A, false)
+            DataType.UWORD, DataType.WORD -> ReturnConvention(returnType, RegisterOrPair.AY, false)
+            DataType.FLOAT -> ReturnConvention(returnType, null, true)
+            in PassByReferenceDatatypes -> ReturnConvention(returnType!!, RegisterOrPair.AY, false)
+            null -> ReturnConvention(null, null, false)
+            else -> {
+                // return type depends on arg type
+                when (val paramType = actualParamTypes.first()) {
+                    DataType.UBYTE, DataType.BYTE -> ReturnConvention(paramType, RegisterOrPair.A, false)
+                    DataType.UWORD, DataType.WORD -> ReturnConvention(paramType, RegisterOrPair.AY, false)
+                    DataType.FLOAT -> ReturnConvention(paramType, null, true)
+                    in PassByReferenceDatatypes -> ReturnConvention(paramType, RegisterOrPair.AY, false)
+                    else -> ReturnConvention(paramType, null, false)
+                }
+            }
+        }
+
+        return when {
+            actualParamTypes.isEmpty() -> CallConvention(emptyList(), returns)
+            actualParamTypes.size==1 -> {
+                // one parameter goes via register/registerpair
+                val paramConv = when(val paramType = actualParamTypes[0]) {
+                    DataType.UBYTE, DataType.BYTE -> ParamConvention(paramType, RegisterOrPair.A, false)
+                    DataType.UWORD, DataType.WORD -> ParamConvention(paramType, RegisterOrPair.AY, false)
+                    DataType.FLOAT -> ParamConvention(paramType, RegisterOrPair.AY, false)
+                    in PassByReferenceDatatypes -> ParamConvention(paramType, RegisterOrPair.AY, false)
+                    else -> ParamConvention(paramType, null, false)
+                }
+                CallConvention(listOf(paramConv), returns)
+            }
+            else -> {
+                // multiple parameters go via variables
+                val paramConvs = actualParamTypes.map { ParamConvention(it, null, true) }
+                CallConvention(paramConvs, returns)
+            }
+        }
+    }
+}
+
+val BuiltinFunctions: Map<String, FSignature> = mapOf(
+    // this set of function have no return value and operate in-place:
+    "setlsb"    to FSignature(false, listOf(FParam("variable", arrayOf(DataType.WORD, DataType.UWORD)), FParam("value", arrayOf(DataType.BYTE, DataType.UBYTE))), null),
+    "setmsb"    to FSignature(false, listOf(FParam("variable", arrayOf(DataType.WORD, DataType.UWORD)), FParam("value", arrayOf(DataType.BYTE, DataType.UBYTE))), null),
+    "rol"       to FSignature(false, listOf(FParam("item", arrayOf(DataType.UBYTE, DataType.UWORD))), null),
+    "ror"       to FSignature(false, listOf(FParam("item", arrayOf(DataType.UBYTE, DataType.UWORD))), null),
+    "rol2"      to FSignature(false, listOf(FParam("item", arrayOf(DataType.UBYTE, DataType.UWORD))), null),
+    "ror2"      to FSignature(false, listOf(FParam("item", arrayOf(DataType.UBYTE, DataType.UWORD))), null),
+    "sort"      to FSignature(false, listOf(FParam("array", ArrayDatatypes)), null),
+    "reverse"   to FSignature(false, listOf(FParam("array", ArrayDatatypes)), null),
+    // cmp returns a status in the carry flag, but not a proper return value
+    "cmp"       to FSignature(false, listOf(FParam("value1", IntegerDatatypesNoBool), FParam("value2", NumericDatatypesNoBool)), null),
+    "prog8_lib_stringcompare"     to FSignature(true, listOf(FParam("str1", arrayOf(DataType.STR)), FParam("str2", arrayOf(DataType.STR))), DataType.BYTE),
+    "prog8_lib_square_byte"       to FSignature(true, listOf(FParam("value", arrayOf(DataType.BYTE, DataType.UBYTE))), DataType.UBYTE),
+    "prog8_lib_square_word"       to FSignature(true, listOf(FParam("value", arrayOf(DataType.WORD, DataType.UWORD))), DataType.UWORD),
+    "abs"       to FSignature(true, listOf(FParam("value", NumericDatatypesNoBool)), null),
+    "abs__byte"  to FSignature(true, listOf(FParam("value", arrayOf(DataType.BYTE))), DataType.BYTE),
+    "abs__word"  to FSignature(true, listOf(FParam("value", arrayOf(DataType.WORD))), DataType.WORD),
+    "abs__float" to FSignature(true, listOf(FParam("value", arrayOf(DataType.FLOAT))), DataType.FLOAT),
+    "len"       to FSignature(true, listOf(FParam("values", IterableDatatypes)), DataType.UWORD),
+    // normal functions follow:
+    "sizeof"    to FSignature(true, listOf(FParam("object", DataType.entries.toTypedArray())), DataType.UBYTE),
+    "sgn"       to FSignature(true, listOf(FParam("value", NumericDatatypesNoBool)), DataType.BYTE),
+    "sqrt"        to FSignature(true, listOf(FParam("value", NumericDatatypesNoBool)), null),
+    "sqrt__ubyte" to FSignature(true, listOf(FParam("value", arrayOf(DataType.UBYTE))), DataType.UBYTE),
+    "sqrt__uword" to FSignature(true, listOf(FParam("value", arrayOf(DataType.UWORD))), DataType.UBYTE),
+    "sqrt__float" to FSignature(true, listOf(FParam("value", arrayOf(DataType.FLOAT))), DataType.FLOAT),
+    "divmod"           to FSignature(false, listOf(FParam("number", arrayOf(DataType.UBYTE, DataType.UWORD)), FParam("divident", arrayOf(DataType.UBYTE, DataType.UWORD)), FParam("division", arrayOf(DataType.UBYTE, DataType.UWORD)), FParam("remainder", arrayOf(DataType.UBYTE, DataType.UWORD))), null),
+    "divmod__ubyte"    to FSignature(false, listOf(FParam("number", arrayOf(DataType.UBYTE)), FParam("divident", arrayOf(DataType.UBYTE)), FParam("division", arrayOf(DataType.UBYTE)), FParam("remainder", arrayOf(DataType.UBYTE))), null),
+    "divmod__uword"    to FSignature(false, listOf(FParam("number", arrayOf(DataType.UWORD)), FParam("divident", arrayOf(DataType.UWORD)), FParam("division", arrayOf(DataType.UWORD)), FParam("remainder", arrayOf(DataType.UWORD))), null),
+    "any"       to FSignature(true, listOf(FParam("values", ArrayDatatypes)), DataType.UBYTE),
+    "all"       to FSignature(true, listOf(FParam("values", ArrayDatatypes)), DataType.UBYTE),
+    "lsb"       to FSignature(true, listOf(FParam("value", arrayOf(DataType.UWORD, DataType.WORD))), DataType.UBYTE),
+    "msb"       to FSignature(true, listOf(FParam("value", arrayOf(DataType.UWORD, DataType.WORD))), DataType.UBYTE),
+    "mkword"    to FSignature(true, listOf(FParam("msb", arrayOf(DataType.UBYTE)), FParam("lsb", arrayOf(DataType.UBYTE))), DataType.UWORD),
+    "clamp"     to FSignature(true, listOf(FParam("value", arrayOf(DataType.BYTE)), FParam("minimum", arrayOf(DataType.BYTE)), FParam("maximum", arrayOf(DataType.BYTE))), null),
+    "clamp__byte"  to FSignature(true, listOf(FParam("value", arrayOf(DataType.BYTE)), FParam("minimum", arrayOf(DataType.BYTE)), FParam("maximum", arrayOf(DataType.BYTE))), DataType.BYTE),
+    "clamp__ubyte" to FSignature(true, listOf(FParam("value", arrayOf(DataType.UBYTE)), FParam("minimum", arrayOf(DataType.UBYTE)), FParam("maximum", arrayOf(DataType.UBYTE))), DataType.UBYTE),
+    "clamp__word"  to FSignature(true, listOf(FParam("value", arrayOf(DataType.WORD)), FParam("minimum", arrayOf(DataType.WORD)), FParam("maximum", arrayOf(DataType.WORD))), DataType.WORD),
+    "clamp__uword" to FSignature(true, listOf(FParam("value", arrayOf(DataType.UWORD)), FParam("minimum", arrayOf(DataType.UWORD)), FParam("maximum", arrayOf(DataType.UWORD))), DataType.UWORD),
+    "min"        to FSignature(true, listOf(FParam("val1", arrayOf(DataType.BYTE)), FParam("val2", arrayOf(DataType.BYTE))), null),
+    "min__byte"  to FSignature(true, listOf(FParam("val1", arrayOf(DataType.BYTE)), FParam("val2", arrayOf(DataType.BYTE))), DataType.BYTE),
+    "min__ubyte" to FSignature(true, listOf(FParam("val1", arrayOf(DataType.UBYTE)), FParam("val2", arrayOf(DataType.UBYTE))), DataType.UBYTE),
+    "min__word"  to FSignature(true, listOf(FParam("val1", arrayOf(DataType.WORD)), FParam("val2", arrayOf(DataType.WORD))), DataType.WORD),
+    "min__uword" to FSignature(true, listOf(FParam("val1", arrayOf(DataType.UWORD)), FParam("val2", arrayOf(DataType.UWORD))), DataType.UWORD),
+    "max"        to FSignature(true, listOf(FParam("val1", arrayOf(DataType.BYTE)), FParam("val2", arrayOf(DataType.BYTE))), null),
+    "max__byte"  to FSignature(true, listOf(FParam("val1", arrayOf(DataType.BYTE)), FParam("val2", arrayOf(DataType.BYTE))), DataType.BYTE),
+    "max__ubyte" to FSignature(true, listOf(FParam("val1", arrayOf(DataType.UBYTE)), FParam("val2", arrayOf(DataType.UBYTE))), DataType.UBYTE),
+    "max__word"  to FSignature(true, listOf(FParam("val1", arrayOf(DataType.WORD)), FParam("val2", arrayOf(DataType.WORD))), DataType.WORD),
+    "max__uword" to FSignature(true, listOf(FParam("val1", arrayOf(DataType.UWORD)), FParam("val2", arrayOf(DataType.UWORD))), DataType.UWORD),
+    "peek"      to FSignature(true, listOf(FParam("address", arrayOf(DataType.UWORD))), DataType.UBYTE),
+    "peekw"     to FSignature(true, listOf(FParam("address", arrayOf(DataType.UWORD))), DataType.UWORD),
+    "peekf"     to FSignature(true, listOf(FParam("address", arrayOf(DataType.UWORD))), DataType.FLOAT),
+    "poke"      to FSignature(false, listOf(FParam("address", arrayOf(DataType.UWORD)), FParam("value", arrayOf(DataType.UBYTE))), null),
+    "pokew"     to FSignature(false, listOf(FParam("address", arrayOf(DataType.UWORD)), FParam("value", arrayOf(DataType.UWORD))), null),
+    "pokef"     to FSignature(false, listOf(FParam("address", arrayOf(DataType.UWORD)), FParam("value", arrayOf(DataType.FLOAT))), null),
+    "pokemon"   to FSignature(false, listOf(FParam("address", arrayOf(DataType.UWORD)), FParam("value", arrayOf(DataType.UBYTE))), DataType.UBYTE),
+    "rsave"     to FSignature(false, emptyList(), null),
+    "rrestore"  to FSignature(false, emptyList(), null),
+    "memory"    to FSignature(true, listOf(FParam("name", arrayOf(DataType.STR)), FParam("size", arrayOf(DataType.UWORD)), FParam("alignment", arrayOf(DataType.UWORD))), DataType.UWORD),
+    "callfar"   to FSignature(false, listOf(FParam("bank", arrayOf(DataType.UBYTE)), FParam("address", arrayOf(DataType.UWORD)), FParam("arg", arrayOf(DataType.UWORD))), DataType.UWORD),
+    "call"      to FSignature(false, listOf(FParam("address", arrayOf(DataType.UWORD))), DataType.UWORD),
+)
+
+val InplaceModifyingBuiltinFunctions = setOf("setlsb", "setmsb", "rol", "ror", "rol2", "ror2", "sort", "reverse")

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

@@ -8,19 +8,32 @@ class CompilationOptions(val output: OutputType,
                          val launcher: CbmPrgLauncherType,
                          val zeropage: ZeropageType,
                          val zpReserved: List<UIntRange>,
+                         val zpAllowed: List<UIntRange>,
                          val floats: Boolean,
                          val noSysInit: Boolean,
                          val compTarget: ICompilationTarget,
                          // these are set later, based on command line arguments or options in the source code:
                          var loadAddress: UInt,
-                         var slowCodegenWarnings: Boolean = false,
+                         var warnSymbolShadowing: Boolean = false,
                          var optimize: Boolean = false,
-                         var optimizeFloatExpressions: Boolean = false,
-                         var dontReinitGlobals: Boolean = false,
                          var asmQuiet: Boolean = false,
                          var asmListfile: Boolean = false,
+                         var includeSourcelines: Boolean = false,
                          var experimentalCodegen: Boolean = false,
-                         var evalStackBaseAddress: UInt? = null,
+                         var varsHighBank: Int? = null,
+                         var varsGolden: Boolean = false,
+                         var slabsHighBank: Int? = null,
+                         var slabsGolden: Boolean = false,
+                         var splitWordArrays: Boolean = false,
+                         var breakpointCpuInstruction: Boolean = false,
                          var outputDir: Path = Path(""),
                          var symbolDefs: Map<String, String> = emptyMap()
-)
+) {
+    init {
+        compTarget.machine.initializeMemoryAreas(this)
+    }
+
+    companion object {
+        val AllZeropageAllowed: List<UIntRange> = listOf(0u..255u)
+    }
+}

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

@@ -1,17 +1,20 @@
 package prog8.code.core
 
 enum class DataType {
-    UBYTE,              // pass by value
+    UBYTE,              // pass by value            8 bits unsigned
-    BYTE,               // pass by value
+    BYTE,               // pass by value            8 bits signed
-    UWORD,              // pass by value
+    UWORD,              // pass by value            16 bits unsigned
-    WORD,               // pass by value
+    WORD,               // pass by value            16 bits signed
-    FLOAT,              // pass by value
+    LONG,               // pass by value            32 bits signed
-    BOOL,               // pass by value
+    FLOAT,              // pass by value            machine dependent
+    BOOL,               // pass by value            bit 0 of a 8 bit byte
     STR,                // pass by reference
     ARRAY_UB,           // pass by reference
     ARRAY_B,            // pass by reference
     ARRAY_UW,           // pass by reference
+    ARRAY_UW_SPLIT,     // pass by reference, lo/hi byte split
     ARRAY_W,            // pass by reference
+    ARRAY_W_SPLIT,      // pass by reference, lo/hi byte split
     ARRAY_F,            // pass by reference
     ARRAY_BOOL,         // pass by reference
     UNDEFINED;
@@ -21,11 +24,12 @@ enum class DataType {
      */
     infix fun isAssignableTo(targetType: DataType) =
         when(this) {
-            BOOL -> targetType.oneOf(BOOL, BYTE, UBYTE, WORD, UWORD, FLOAT)
+            BOOL -> targetType.oneOf(BOOL, BYTE, UBYTE, WORD, UWORD, LONG, FLOAT)
-            UBYTE -> targetType.oneOf(UBYTE, WORD, UWORD, FLOAT, BOOL)
+            UBYTE -> targetType.oneOf(UBYTE, WORD, UWORD, LONG, FLOAT, BOOL)
-            BYTE -> targetType.oneOf(BYTE, WORD, FLOAT)
+            BYTE -> targetType.oneOf(BYTE, WORD, LONG, FLOAT)
-            UWORD -> targetType.oneOf(UWORD, FLOAT)
+            UWORD -> targetType.oneOf(UWORD, LONG, FLOAT)
-            WORD -> targetType.oneOf(WORD, FLOAT)
+            WORD -> targetType.oneOf(WORD, LONG, FLOAT)
+            LONG -> targetType.oneOf(LONG, FLOAT)
             FLOAT -> targetType.oneOf(FLOAT)
             STR -> targetType.oneOf(STR, UWORD)
             in ArrayDatatypes -> targetType == this
@@ -39,7 +43,8 @@ enum class DataType {
             this == other -> false
             this in ByteDatatypes -> false
             this in WordDatatypes -> other in ByteDatatypes
-            this== STR && other== UWORD || this== UWORD && other== STR -> false
+            this == LONG -> other in ByteDatatypes+WordDatatypes
+            this == STR && other == UWORD || this == UWORD && other == STR -> false
             else -> true
         }
 
@@ -74,6 +79,13 @@ enum class RegisterOrPair {
 
     companion object {
         val names by lazy { values().map { it.toString()} }
+        fun fromCpuRegister(cpu: CpuRegister): RegisterOrPair {
+            return when(cpu) {
+                CpuRegister.A -> A
+                CpuRegister.X -> X
+                CpuRegister.Y -> Y
+            }
+        }
     }
 
     fun asCpuRegister(): CpuRegister = when(this) {
@@ -108,23 +120,25 @@ enum class BranchCondition {
     PL,     // PL == POS
     POS,
     VS,
-    VC,
+    VC
 }
 
 
 val ByteDatatypes = arrayOf(DataType.UBYTE, DataType.BYTE, DataType.BOOL)
 val WordDatatypes = arrayOf(DataType.UWORD, DataType.WORD)
-val IntegerDatatypes = arrayOf(DataType.UBYTE, DataType.BYTE, DataType.UWORD, DataType.WORD, DataType.BOOL)
+val IntegerDatatypesNoBool = arrayOf(DataType.UBYTE, DataType.BYTE, DataType.UWORD, DataType.WORD, DataType.LONG)
-val IntegerDatatypesNoBool = arrayOf(DataType.UBYTE, DataType.BYTE, DataType.UWORD, DataType.WORD)
+val IntegerDatatypes = IntegerDatatypesNoBool + DataType.BOOL
-val NumericDatatypes = arrayOf(DataType.UBYTE, DataType.BYTE, DataType.UWORD, DataType.WORD, DataType.FLOAT, DataType.BOOL)
+val NumericDatatypesNoBool = arrayOf(DataType.UBYTE, DataType.BYTE, DataType.UWORD, DataType.WORD, DataType.LONG, DataType.FLOAT)
-val NumericDatatypesNoBool = arrayOf(DataType.UBYTE, DataType.BYTE, DataType.UWORD, DataType.WORD, DataType.FLOAT)
+val NumericDatatypes = NumericDatatypesNoBool + DataType.BOOL
-val SignedDatatypes =  arrayOf(DataType.BYTE, DataType.WORD, DataType.FLOAT)
+val SignedDatatypes =  arrayOf(DataType.BYTE, DataType.WORD, DataType.LONG, DataType.FLOAT)
-val ArrayDatatypes = arrayOf(DataType.ARRAY_UB, DataType.ARRAY_B, DataType.ARRAY_UW, DataType.ARRAY_W, DataType.ARRAY_F, DataType.ARRAY_BOOL)
+val ArrayDatatypes = arrayOf(DataType.ARRAY_UB, DataType.ARRAY_B, DataType.ARRAY_UW, DataType.ARRAY_UW_SPLIT, DataType.ARRAY_W, DataType.ARRAY_W_SPLIT, DataType.ARRAY_F, DataType.ARRAY_BOOL)
 val StringlyDatatypes = arrayOf(DataType.STR, DataType.ARRAY_UB, DataType.ARRAY_B, DataType.UWORD)
+val SplitWordArrayTypes = arrayOf(DataType.ARRAY_UW_SPLIT, DataType.ARRAY_W_SPLIT)
 val IterableDatatypes = arrayOf(
     DataType.STR,
     DataType.ARRAY_UB, DataType.ARRAY_B,
     DataType.ARRAY_UW, DataType.ARRAY_W,
+    DataType.ARRAY_UW_SPLIT, DataType.ARRAY_W_SPLIT,
     DataType.ARRAY_F, DataType.ARRAY_BOOL
 )
 val PassByValueDatatypes = NumericDatatypes
@@ -135,6 +149,8 @@ val ArrayToElementTypes = mapOf(
     DataType.ARRAY_UB to DataType.UBYTE,
     DataType.ARRAY_W to DataType.WORD,
     DataType.ARRAY_UW to DataType.UWORD,
+    DataType.ARRAY_W_SPLIT to DataType.WORD,
+    DataType.ARRAY_UW_SPLIT to DataType.UWORD,
     DataType.ARRAY_F to DataType.FLOAT,
     DataType.ARRAY_BOOL to DataType.BOOL
 )
@@ -144,8 +160,10 @@ val ElementToArrayTypes = mapOf(
     DataType.WORD to DataType.ARRAY_W,
     DataType.UWORD to DataType.ARRAY_UW,
     DataType.FLOAT to DataType.ARRAY_F,
-    DataType.BOOL to DataType.ARRAY_BOOL
+    DataType.BOOL to DataType.ARRAY_BOOL,
+    DataType.STR to DataType.ARRAY_UW          // array of str is just an array of pointers
 )
+
 val Cx16VirtualRegisters = arrayOf(
     RegisterOrPair.R0, RegisterOrPair.R1, RegisterOrPair.R2, RegisterOrPair.R3,
     RegisterOrPair.R4, RegisterOrPair.R5, RegisterOrPair.R6, RegisterOrPair.R7,
@@ -153,6 +171,10 @@ val Cx16VirtualRegisters = arrayOf(
     RegisterOrPair.R12, RegisterOrPair.R13, RegisterOrPair.R14, RegisterOrPair.R15
 )
 
+val CpuRegisters = setOf(
+    RegisterOrPair.A, RegisterOrPair.X, RegisterOrPair.Y,
+    RegisterOrPair.AX, RegisterOrPair.AY, RegisterOrPair.XY
+)
 
 
 enum class OutputType {

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

@@ -1,12 +0,0 @@
-package prog8.code.core
-
-interface IAssemblyGenerator {
-    fun compileToAssembly(): IAssemblyProgram?
-}
-
-interface IAssemblyProgram {
-    val name: String
-    fun assemble(options: CompilationOptions): Boolean
-}
-
-fun viceMonListName(baseFilename: String) = "$baseFilename.vice-mon-list"

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

@@ -0,0 +1,17 @@
+package prog8.code.core
+
+import prog8.code.SymbolTable
+import prog8.code.ast.PtProgram
+
+interface ICodeGeneratorBackend {
+    fun generate(program: PtProgram,
+                 symbolTable: SymbolTable,
+                 options: CompilationOptions,
+                 errors: IErrorReporter): IAssemblyProgram?
+}
+
+
+interface IAssemblyProgram {
+    val name: String
+    fun assemble(options: CompilationOptions, errors: IErrorReporter): Boolean
+}

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

@@ -3,9 +3,7 @@ package prog8.code.core
 interface ICompilationTarget: IStringEncoding, IMemSizer {
     val name: String
     val machine: IMachineDefinition
-    val supportedEncodings: Set<Encoding>
-    val defaultEncoding: Encoding
 
     override fun encodeString(str: String, encoding: Encoding): List<UByte>
-    override fun decodeString(bytes: List<UByte>, encoding: Encoding): String
+    override fun decodeString(bytes: Iterable<UByte>, encoding: Encoding): String
 }

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

@@ -3,10 +3,12 @@ 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) {
+    fun finalizeNumErrors(numErrors: Int, numWarnings: Int, numInfos: Int) {
         if(numErrors>0)
-            throw ErrorsReportedException("There are $numErrors errors and $numWarnings warnings.")
+            throw ErrorsReportedException("There are $numErrors errors, $numWarnings warnings, and $numInfos infos.")
     }
 }

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

@@ -13,9 +13,11 @@ interface IMachineDefinition {
     val FLOAT_MAX_NEGATIVE: Double
     val FLOAT_MAX_POSITIVE: Double
     val FLOAT_MEM_SIZE: Int
-    var ESTACK_LO: UInt
-    var ESTACK_HI: UInt
     val PROGRAM_LOAD_ADDRESS : UInt
+    val BSSHIGHRAM_START: UInt
+    val BSSHIGHRAM_END: UInt
+    val BSSGOLDENRAM_START: UInt
+    val BSSGOLDENRAM_END: UInt
 
     val cpu: CpuType
     var zeropage: Zeropage
@@ -27,11 +29,4 @@ interface IMachineDefinition {
     fun importLibs(compilerOptions: CompilationOptions, compilationTargetName: String): List<String>
     fun launchEmulator(selectedEmulator: Int, programNameWithPath: Path)
     fun isIOAddress(address: UInt): Boolean
-    fun overrideEvalStack(evalStackBaseAddress: UInt) {
-        require(evalStackBaseAddress and 255u == 0u)
-        ESTACK_LO = evalStackBaseAddress
-        ESTACK_HI = evalStackBaseAddress + 256u
-        require(ESTACK_LO !in golden.region && ESTACK_HI !in golden.region) { "user-set ESTACK can't be in GOLDEN ram" }
-    }
-
 }

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

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

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

@@ -11,7 +11,7 @@ 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: List<String>,
+    abstract fun allocate(name: String,
                           datatype: DataType,
                           numElements: Int?,
                           position: Position?,
@@ -29,7 +29,7 @@ abstract class Zeropage(options: CompilationOptions): MemoryAllocator(options) {
 
     // the variables allocated into Zeropage.
     // name (scoped) ==> pair of address to (Datatype + bytesize)
-    val allocatedVariables = mutableMapOf<List<String>, VarAllocation>()
+    val allocatedVariables = mutableMapOf<String, VarAllocation>()
 
     val free = mutableListOf<UInt>()     // subclasses must set this to the appropriate free locations.
 
@@ -42,6 +42,13 @@ abstract class Zeropage(options: CompilationOptions): MemoryAllocator(options) {
         }
     }
 
+    fun retainAllowed() {
+        synchronized(this) {
+            for(allowed in options.zpAllowed)
+                free.retainAll { it in allowed }
+        }
+    }
+
     fun availableBytes() = if(options.zeropage== ZeropageType.DONTUSE) 0 else free.size
     fun hasByteAvailable() = if(options.zeropage== ZeropageType.DONTUSE) false else free.isNotEmpty()
     fun hasWordAvailable(): Boolean {
@@ -51,7 +58,7 @@ abstract class Zeropage(options: CompilationOptions): MemoryAllocator(options) {
         return free.windowed(2).any { it[0] == it[1] - 1u }
     }
 
-    override fun allocate(name: List<String>,
+    override fun allocate(name: String,
                           datatype: DataType,
                           numElements: Int?,
                           position: Position?,
@@ -107,7 +114,7 @@ abstract class Zeropage(options: CompilationOptions): MemoryAllocator(options) {
 
     private fun reserve(range: UIntRange) = free.removeAll(range)
 
-    private fun makeAllocation(address: UInt, size: Int, datatype: DataType, name: List<String>): UInt {
+    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()) {
@@ -131,11 +138,12 @@ abstract class Zeropage(options: CompilationOptions): MemoryAllocator(options) {
 }
 
 
+// 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: List<String>,
+        name: String,
         datatype: DataType,
         numElements: Int?,
         position: Position?,

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

@@ -1,11 +1,10 @@
 package prog8.code.core
 
-val AssociativeOperators = setOf("+", "*", "&", "|", "^", "==", "!=")
+val AssociativeOperators = setOf("+", "*", "&", "|", "^", "==", "!=", "and", "or", "xor")
 val ComparisonOperators = setOf("==", "!=", "<", ">", "<=", ">=")
 val LogicalOperators = setOf("and", "or", "xor", "not")
-val AugmentAssignmentOperators = setOf("+", "-", "/", "*", "&", "|", "^", "<<", ">>", "%", "and", "or", "xor")
 val BitwiseOperators = setOf("&", "|", "^", "~")
-// val InvalidOperatorsForBoolean = setOf("+", "-", "*", "/", "%", "<<", ">>") + BitwiseOperators
+val PrefixOperators = setOf("+", "-", "~", "not")
 
 fun invertedComparisonOperator(operator: String) =
     when (operator) {

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

@@ -1,5 +1,6 @@
 package prog8.code.core
 
+import prog8.code.core.SourceCode.Companion.LIBRARYFILEPREFIX
 import java.nio.file.InvalidPathException
 import kotlin.io.path.Path
 import kotlin.io.path.absolute
@@ -7,6 +8,10 @@ import kotlin.io.path.absolute
 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(file.startsWith(LIBRARYFILEPREFIX))
+            return "$file:$line:$startCol:"
         return try {
             val path = Path(file).absolute().normalize().toString()
             "file://$path:$line:$startCol:"

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

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

codeCore/src/prog8/code/optimize/Optimizer.kt

@@ -0,0 +1,127 @@
+package prog8.code.optimize
+
+import prog8.code.ast.*
+import prog8.code.core.*
+
+
+fun optimizeIntermediateAst(program: PtProgram, options: CompilationOptions, errors: IErrorReporter) {
+    if (!options.optimize)
+        return
+    while(errors.noErrors() && optimizeCommonSubExpressions(program, errors)>0) {
+        // keep rolling
+    }
+}
+
+
+private fun walkAst(root: PtNode, act: (node: PtNode, depth: Int) -> Boolean) {
+    fun recurse(node: PtNode, depth: Int) {
+        if(act(node, depth))
+            node.children.forEach { recurse(it, depth+1) }
+    }
+    recurse(root, 0)
+}
+
+
+private fun optimizeCommonSubExpressions(program: PtProgram, errors: IErrorReporter): Int {
+
+    fun extractableSubExpr(expr: PtExpression): Boolean {
+        val result = if(expr is PtBinaryExpression)
+            expr.type !in ByteDatatypes ||
+                    !expr.left.isSimple() ||
+                    !expr.right.isSimple() ||
+                    (expr.operator !in LogicalOperators && expr.operator !in BitwiseOperators)
+        else if (expr is PtArrayIndexer && expr.type !in ByteDatatypes)
+            true
+        else
+            !expr.isSimple()
+        return result
+    }
+
+    // for each Binaryexpression, recurse to find a common subexpression pair therein.
+    val commons = mutableMapOf<PtBinaryExpression, Pair<PtExpression, PtExpression>>()
+    walkAst(program) { node: PtNode, depth: Int ->
+        if(node is PtBinaryExpression) {
+            val subExpressions = mutableListOf<PtExpression>()
+            walkAst(node.left) { subNode: PtNode, subDepth: Int ->
+                if (subNode is PtExpression) {
+                    if(extractableSubExpr(subNode)) subExpressions.add(subNode)
+                    true
+                } else false
+            }
+            walkAst(node.right) { subNode: PtNode, subDepth: Int ->
+                if (subNode is PtExpression) {
+                    if(extractableSubExpr(subNode)) subExpressions.add(subNode)
+                    true
+                } else false
+            }
+
+            outer@for (first in subExpressions) {
+                for (second in subExpressions) {
+                    if (first!==second && first isSameAs second) {
+                        commons[node] = first to second
+                        break@outer     // do only 1 replacement at a time per binaryexpression
+                    }
+                }
+            }
+            false
+        } else true
+    }
+
+    // replace common subexpressions by a temp variable that is assigned only once.
+    // TODO: check for commonalities across multiple separate expressions in the current scope, not only inside a single line
+    commons.forEach { binexpr, (occurrence1, occurrence2) ->
+        val (stmtContainer, stmt) = findContainingStatements(binexpr)
+        val occurrence1idx = occurrence1.parent.children.indexOf(occurrence1)
+        val occurrence2idx = occurrence2.parent.children.indexOf(occurrence2)
+        val containerScopedName = findScopeName(stmtContainer)
+        val tempvarName = "subexprvar_line${binexpr.position.line}_${binexpr.hashCode().toUInt()}"
+        // TODO: some tempvars could be reused, if they are from different lines
+
+        val datatype = occurrence1.type
+        val singleReplacement1 = PtIdentifier("$containerScopedName.$tempvarName", datatype, occurrence1.position)
+        val singleReplacement2 = PtIdentifier("$containerScopedName.$tempvarName", datatype, occurrence2.position)
+        occurrence1.parent.children[occurrence1idx] = singleReplacement1
+        singleReplacement1.parent = occurrence1.parent
+        occurrence2.parent.children[occurrence2idx] = singleReplacement2
+        singleReplacement2.parent = occurrence2.parent
+
+        val tempassign = PtAssignment(binexpr.position).also { assign ->
+            assign.add(PtAssignTarget(binexpr.position).also { tgt->
+                tgt.add(PtIdentifier("$containerScopedName.$tempvarName", datatype, binexpr.position))
+            })
+            assign.add(occurrence1)
+            occurrence1.parent = assign
+        }
+        stmtContainer.children.add(stmtContainer.children.indexOf(stmt), tempassign)
+        tempassign.parent = stmtContainer
+
+        val tempvar = PtVariable(tempvarName, datatype, ZeropageWish.DONTCARE, null, null, binexpr.position)
+        stmtContainer.add(0, tempvar)
+        tempvar.parent = stmtContainer
+
+        // errors.info("common subexpressions replaced by a tempvar, maybe simplify the expression manually", binexpr.position)
+    }
+
+    return commons.size
+}
+
+
+internal fun findScopeName(node: PtNode): String {
+    var parent=node
+    while(parent !is PtNamedNode)
+        parent = parent.parent
+    return parent.scopedName
+}
+
+
+internal fun findContainingStatements(node: PtNode): Pair<PtNode, PtNode> {      // returns (parentstatementcontainer, childstatement)
+    var parent = node.parent
+    var child = node
+    while(true) {
+        if(parent is IPtStatementContainer) {
+            return parent to child
+        }
+        child=parent
+        parent=parent.parent
+    }
+}

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

@@ -7,7 +7,6 @@ import prog8.code.target.atari.AtariMachineDefinition
 class AtariTarget: ICompilationTarget, IStringEncoding by Encoder, IMemSizer {
     override val name = NAME
     override val machine = AtariMachineDefinition()
-    override val supportedEncodings = setOf(Encoding.ATASCII)
     override val defaultEncoding = Encoding.ATASCII
 
     companion object {
@@ -19,7 +18,7 @@ class AtariTarget: ICompilationTarget, IStringEncoding by Encoder, IMemSizer {
             in ByteDatatypes -> 1
             in WordDatatypes, in PassByReferenceDatatypes -> 2
             DataType.FLOAT -> machine.FLOAT_MEM_SIZE
-            else -> Int.MIN_VALUE
+            else -> throw IllegalArgumentException("invalid datatype")
         }
     }
 

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

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

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

@@ -11,10 +11,11 @@ import prog8.code.target.cbm.CbmMemorySizer
 class C64Target: ICompilationTarget, IStringEncoding by Encoder, IMemSizer by CbmMemorySizer {
     override val name = NAME
     override val machine = C64MachineDefinition()
-    override val supportedEncodings = setOf(Encoding.PETSCII, Encoding.SCREENCODES)
     override val defaultEncoding = Encoding.PETSCII
 
     companion object {
         const val NAME = "c64"
+
+        fun viceMonListName(baseFilename: String) = "$baseFilename.vice-mon-list"
     }
 }

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

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

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

@@ -10,6 +10,8 @@ import prog8.code.target.cbm.PetsciiEncoding
 
 
 object Encoder: IStringEncoding {
+    override val defaultEncoding: Encoding = Encoding.ISO
+
     override fun encodeString(str: String, encoding: Encoding): List<UByte> {
         val coded = when(encoding) {
             Encoding.PETSCII -> PetsciiEncoding.encodePetscii(str, true)
@@ -23,7 +25,7 @@ object Encoder: IStringEncoding {
             success = { it }
         )
     }
-    override fun decodeString(bytes: List<UByte>, encoding: Encoding): String {
+    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)

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

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

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

@@ -6,7 +6,6 @@ import prog8.code.target.virtual.VirtualMachineDefinition
 class VMTarget: ICompilationTarget, IStringEncoding by Encoder, IMemSizer {
     override val name = NAME
     override val machine = VirtualMachineDefinition()
-    override val supportedEncodings = setOf(Encoding.ISO)
     override val defaultEncoding = Encoding.ISO
 
     companion object {
@@ -18,7 +17,7 @@ class VMTarget: ICompilationTarget, IStringEncoding by Encoder, IMemSizer {
             in ByteDatatypes -> 1
             in WordDatatypes, in PassByReferenceDatatypes -> 2
             DataType.FLOAT -> machine.FLOAT_MEM_SIZE
-            else -> Int.MIN_VALUE
+            else -> throw IllegalArgumentException("invalid datatype")
         }
     }
 

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

@@ -13,14 +13,15 @@ class AtariMachineDefinition: IMachineDefinition {
     override val FLOAT_MEM_SIZE = 6
     override val PROGRAM_LOAD_ADDRESS = 0x2000u
 
-    // the 2*256 byte evaluation stack (on which bytes, words, and even floats are stored during calculations)
+    override val BSSHIGHRAM_START = 0u    // TODO
-    override var ESTACK_LO = 0x1a00u     //  $1a00-$1aff inclusive      // TODO
+    override val BSSHIGHRAM_END = 0u      // TODO
-    override var ESTACK_HI = 0x1b00u     //  $1b00-$1bff inclusive      // 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) = TODO("float asm bytes from number")
+    override fun getFloatAsmBytes(num: Number) = TODO("atari float asm bytes from number")
 
     override fun importLibs(compilerOptions: CompilationOptions, compilationTargetName: String): List<String> {
         return if (compilerOptions.output == OutputType.XEX)

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

@@ -13,6 +13,10 @@ class AtariZeropage(options: CompilationOptions) : Zeropage(options) {
     override val SCRATCH_W2 = 0xcfu      // temp storage 2 for a word  $cf+$d0        TODO is $d0 okay to use?
 
     init {
+        if (options.floats) {
+            throw InternalCompilerException("Atari target doesn't yet support floating point routines")
+        }
+
         if (options.floats && options.zeropage !in arrayOf(
                 ZeropageType.FLOATSAFE,
                 ZeropageType.BASICSAFE,
@@ -39,11 +43,12 @@ class AtariZeropage(options: CompilationOptions) : Zeropage(options) {
             }
         }
 
-        val distictFree = free.distinct()
+        val distinctFree = free.distinct()
         free.clear()
-        free.addAll(distictFree)
+        free.addAll(distinctFree)
 
         removeReservedFromFreePool()
+        retainAllowed()
     }
 
     override fun allocateCx16VirtualRegisters() {

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

@@ -1,6 +1,7 @@
 package prog8.code.target.c128
 
 import prog8.code.core.*
+import prog8.code.target.C64Target
 import prog8.code.target.cbm.Mflpt5
 import java.nio.file.Path
 
@@ -14,9 +15,11 @@ class C128MachineDefinition: IMachineDefinition {
     override val FLOAT_MEM_SIZE = Mflpt5.FLOAT_MEM_SIZE
     override val PROGRAM_LOAD_ADDRESS = 0x1c01u
 
-    // the 2*256 byte evaluation stack (on which bytes, words, and even floats are stored during calculations)
+    override val BSSHIGHRAM_START = 0u    // TODO
-    override var ESTACK_LO = 0x1a00u     //  $1a00-$1aff inclusive
+    override val BSSHIGHRAM_END = 0u      // TODO
-    override var ESTACK_HI = 0x1b00u     //  $1b00-$1bff inclusive
+    override val BSSGOLDENRAM_START = 0u  // TODO
+    override val BSSGOLDENRAM_END = 0u    // TODO
+
     override lateinit var zeropage: Zeropage
     override lateinit var golden: GoldenRam
 
@@ -36,7 +39,7 @@ class C128MachineDefinition: IMachineDefinition {
         }
 
         println("\nStarting C-128 emulator x128...")
-        val viceMonlist = viceMonListName(programNameWithPath.toString())
+        val viceMonlist = C64Target.viceMonListName(programNameWithPath.toString())
         val cmdline = listOf("x128", "-silent", "-moncommands", viceMonlist,
                 "-autostartprgmode", "1", "-autostart-warp", "-autostart", "${programNameWithPath}.prg")
         val processb = ProcessBuilder(cmdline).inheritIO()

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

@@ -6,15 +6,22 @@ import prog8.code.core.Zeropage
 import prog8.code.core.ZeropageType
 
 
+// reference: "Mapping the C128" zero page chapter.
+
 class C128Zeropage(options: CompilationOptions) : Zeropage(options) {
 
-    override val SCRATCH_B1 = 0x9bu      // temp storage for a single byte
+    override val SCRATCH_B1 = 0x74u      // temp storage for a single byte
-    override val SCRATCH_REG = 0x9cu     // temp storage for a register, must be B1+1
+    override val SCRATCH_REG = 0x75u     // temp storage for a register, 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) {
+            throw InternalCompilerException("C128 target doesn't yet support floating point routines")
+            // note: in git commit labeled 'c128: remove floats module' the floats.p8 and floats.asm files are removed,
+            //       they could be retrieved again at a later time if the compiler somehow *does* store the fp variables in bank1.
+        }
+
         if (options.floats && options.zeropage !in arrayOf(
                 ZeropageType.FLOATSAFE,
                 ZeropageType.BASICSAFE,
@@ -24,25 +31,45 @@ class C128Zeropage(options: CompilationOptions) : Zeropage(options) {
 
         when (options.zeropage) {
             ZeropageType.FULL -> {
-                // TODO all c128 usable zero page locations, except the ones used by the system's IRQ routine
+                // $00/$01 are data port IO registers, // $02-$09 are storage locations for JSRFAR and such
-                free.addAll(0x0au..0xffu)       // TODO c128 what about $02-$09?
+                free.addAll(0x0au..0xffu)
-                // TODO c128  free.removeAll(setOf(0xa0u, 0xa1u, 0xa2u, 0x91u, 0xc0u, 0xc5u, 0xcbu, 0xf5u, 0xf6u))        // these are updated by IRQ
+                free.removeAll(listOf(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(listOf(0x92u, 0x96u, 0x9bu, 0x9cu, 0x9eu, 0x9fu, 0xa4u, 0xa7u, 0xa8u, 0xa9u, 0xaau, 0xabu,
+                    0xb0u, 0xb1u, 0xb4u, 0xb5u, 0xb6u))
             }
-            ZeropageType.KERNALSAFE,
             ZeropageType.FLOATSAFE,
             ZeropageType.BASICSAFE -> {
-                free.clear()   // TODO c128 usable zero page addresses
+                free.addAll(listOf(0x0bu, 0x0cu, 0x0du, 0x0eu, 0x0fu, 0x10u, 0x11u, 0x12u, 0x16u, 0x17u, 0x18u, 0x19u, 0x1au))
+                free.addAll(0x1bu..0x23u)
+                free.addAll(listOf(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(listOf(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 distictFree = free.distinct()
+        val distinctFree = free.distinct()
         free.clear()
-        free.addAll(distictFree)
+        free.addAll(distinctFree)
 
         removeReservedFromFreePool()
+        retainAllowed()
     }
 
     override fun allocateCx16VirtualRegisters() {

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

@@ -1,6 +1,7 @@
 package prog8.code.target.c64
 
 import prog8.code.core.*
+import prog8.code.target.C64Target
 import prog8.code.target.cbm.Mflpt5
 import java.io.IOException
 import java.nio.file.Path
@@ -15,9 +16,11 @@ class C64MachineDefinition: IMachineDefinition {
     override val FLOAT_MEM_SIZE = Mflpt5.FLOAT_MEM_SIZE
     override val PROGRAM_LOAD_ADDRESS = 0x0801u
 
-    // the 2*256 byte evaluation stack (on which bytes, words, and even floats are stored during calculations)
+    override val BSSHIGHRAM_START = 0xc000u
-    override var ESTACK_LO = 0xce00u     //  $ce00-$ceff inclusive
+    override val BSSHIGHRAM_END = 0xcfffu
-    override var ESTACK_HI = 0xcf00u     //  $ce00-$ceff inclusive
+    override val BSSGOLDENRAM_START = 0u
+    override val BSSGOLDENRAM_END = 0u
+
     override lateinit var zeropage: Zeropage
     override lateinit var golden: GoldenRam
 
@@ -38,7 +41,7 @@ class C64MachineDefinition: IMachineDefinition {
 
         for(emulator in listOf("x64sc", "x64")) {
             println("\nStarting C-64 emulator $emulator...")
-            val viceMonlist = viceMonListName(programNameWithPath.toString())
+            val viceMonlist = C64Target.viceMonListName(programNameWithPath.toString())
             val cmdline = listOf(emulator, "-silent", "-moncommands", viceMonlist,
                     "-autostartprgmode", "1", "-autostart-warp", "-autostart", "${programNameWithPath}.prg")
             val processb = ProcessBuilder(cmdline).inheritIO()
@@ -57,7 +60,7 @@ class C64MachineDefinition: IMachineDefinition {
 
     override fun initializeMemoryAreas(compilerOptions: CompilationOptions) {
         zeropage = C64Zeropage(compilerOptions)
-        golden = GoldenRam(compilerOptions, 0xc000u until ESTACK_LO)
+        golden = GoldenRam(compilerOptions, 0xc000u until 0xd000u)
     }
 
 }

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

@@ -44,7 +44,7 @@ class C64Zeropage(options: CompilationOptions) : Zeropage(options) {
             if (options.zeropage == ZeropageType.FLOATSAFE) {
                 // remove the zeropage locations used for floating point operations from the free list
                 free.removeAll(listOf(
-                        0x03, 0x04, 0x10, 0x11, 0x12,
+                        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,
@@ -53,11 +53,11 @@ class C64Zeropage(options: CompilationOptions) : Zeropage(options) {
                 ).map{it.toUInt()})
             }
 
-            if(options.zeropage!= ZeropageType.DONTUSE) {
+            if(options.zeropage != ZeropageType.DONTUSE) {
                 // add the free Zp addresses
                 // these are valid for the C-64 but allow BASIC to keep running fully *as long as you don't use tape I/O*
                 free.addAll(listOf(0x02, 0x03, 0x04, 0x05, 0x06, 0x0a, 0x0e,
-                        0x92, 0x96, 0x9b, 0x9c, 0x9e, 0x9f, 0xa5, 0xa6,
+                        0x92, 0x96, 0x9b, 0x9c, 0x9e, 0x9f, 0xa6,
                         0xb0, 0xb1, 0xbe, 0xbf, 0xf9).map{it.toUInt()})
             } else {
                 // don't use the zeropage at all
@@ -65,9 +65,9 @@ class C64Zeropage(options: CompilationOptions) : Zeropage(options) {
             }
         }
 
-        val distictFree = free.distinct()
+        val distinctFree = free.distinct()
         free.clear()
-        free.addAll(distictFree)
+        free.addAll(distinctFree)
 
         removeReservedFromFreePool()
 
@@ -75,6 +75,8 @@ class C64Zeropage(options: CompilationOptions) : Zeropage(options) {
             // in these cases there is enough space on the zero page to stick the cx16 virtual registers in there as well.
             allocateCx16VirtualRegisters()
         }
+
+        retainAllowed()
     }
 
     override fun allocateCx16VirtualRegisters() {
@@ -83,12 +85,12 @@ class C64Zeropage(options: CompilationOptions) : Zeropage(options) {
         // 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 ($02).
         for(reg in 0..15) {
-            allocatedVariables[listOf("cx16", "r${reg}")]   = VarAllocation((4+reg*2).toUInt(), DataType.UWORD, 2)       // cx16.r0 .. cx16.r15
+            allocatedVariables["cx16.r${reg}"]   = VarAllocation((4+reg*2).toUInt(), DataType.UWORD, 2)       // cx16.r0 .. cx16.r15
-            allocatedVariables[listOf("cx16", "r${reg}s")]  = VarAllocation((4+reg*2).toUInt(), DataType.WORD, 2)        // cx16.r0s .. cx16.r15s
+            allocatedVariables["cx16.r${reg}s"]  = VarAllocation((4+reg*2).toUInt(), DataType.WORD, 2)        // cx16.r0s .. cx16.r15s
-            allocatedVariables[listOf("cx16", "r${reg}L")]  = VarAllocation((4+reg*2).toUInt(), DataType.UBYTE, 1)       // cx16.r0L .. cx16.r15L
+            allocatedVariables["cx16.r${reg}L"]  = VarAllocation((4+reg*2).toUInt(), DataType.UBYTE, 1)       // cx16.r0L .. cx16.r15L
-            allocatedVariables[listOf("cx16", "r${reg}H")]  = VarAllocation((5+reg*2).toUInt(), DataType.UBYTE, 1)       // cx16.r0H .. cx16.r15H
+            allocatedVariables["cx16.r${reg}H"]  = VarAllocation((5+reg*2).toUInt(), DataType.UBYTE, 1)       // cx16.r0H .. cx16.r15H
-            allocatedVariables[listOf("cx16", "r${reg}sL")] = VarAllocation((4+reg*2).toUInt(), DataType.BYTE, 1)        // cx16.r0sL .. cx16.r15sL
+            allocatedVariables["cx16.r${reg}sL"] = VarAllocation((4+reg*2).toUInt(), DataType.BYTE, 1)        // cx16.r0sL .. cx16.r15sL
-            allocatedVariables[listOf("cx16", "r${reg}sH")] = VarAllocation((5+reg*2).toUInt(), DataType.BYTE, 1)        // cx16.r0sH .. cx16.r15sH
+            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/cbm/AtasciiEncoding.kt

@@ -208,7 +208,7 @@ object AtasciiEncoding {
         return Ok(mapped)
     }
 
-    fun decode(bytes: List<UByte>): Result<String, CharConversionException> {
+    fun decode(bytes: Iterable<UByte>): Result<String, CharConversionException> {
         return Ok(bytes.map { decodeTable[it.toInt()] }.joinToString(""))
     }
 }

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

@@ -9,7 +9,7 @@ internal object CbmMemorySizer: IMemSizer {
             in ByteDatatypes -> 1
             in WordDatatypes, in PassByReferenceDatatypes -> 2
             DataType.FLOAT -> Mflpt5.FLOAT_MEM_SIZE
-            else -> Int.MIN_VALUE
+            else -> throw IllegalArgumentException("invalid datatype")
         }
     }
 

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

@@ -27,7 +27,7 @@ object IsoEncoding {
         }
     }
 
-    fun decode(bytes: List<UByte>): Result<String, CharConversionException> {
+    fun decode(bytes: Iterable<UByte>): Result<String, CharConversionException> {
         return try {
             Ok(String(bytes.map { it.toByte() }.toByteArray(), charset))
         } catch (ce: CharConversionException) {

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

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

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

@@ -1,6 +1,7 @@
 package prog8.code.target.cx16
 
 import prog8.code.core.*
+import prog8.code.target.C64Target
 import prog8.code.target.cbm.Mflpt5
 import java.nio.file.Path
 
@@ -14,9 +15,11 @@ class CX16MachineDefinition: IMachineDefinition {
     override val FLOAT_MEM_SIZE = Mflpt5.FLOAT_MEM_SIZE
     override val PROGRAM_LOAD_ADDRESS = 0x0801u
 
-    // the 2*256 byte evaluation stack (on which bytes, words, and even floats are stored during calculations)
+    override val BSSHIGHRAM_START = 0xa000u     // hiram bank 1, 8Kb, assumed to be active
-    override var ESTACK_LO = 0x0400u        //  $0400-$04ff inclusive
+    override val BSSHIGHRAM_END = 0xbfffu       // Rom starts at $c000
-    override var ESTACK_HI = 0x0500u        //  $0500-$05ff inclusive
+    override val BSSGOLDENRAM_START = 0x0400u
+    override val BSSGOLDENRAM_END = 0x07ffu
+
     override lateinit var zeropage: Zeropage
     override lateinit var golden: GoldenRam
 
@@ -35,11 +38,11 @@ class CX16MachineDefinition: IMachineDefinition {
         when(selectedEmulator) {
             1 -> {
                 emulator = "x16emu"
-                extraArgs = emptyList()
+                extraArgs = listOf("-debug")
             }
             2 -> {
                 emulator = "box16"
-                extraArgs = listOf("-sym", viceMonListName(programNameWithPath.toString()))
+                extraArgs = listOf("-sym", C64Target.viceMonListName(programNameWithPath.toString()))
             }
             else -> {
                 System.err.println("Cx16 target only supports x16emu and box16 emulators.")
@@ -48,7 +51,7 @@ class CX16MachineDefinition: IMachineDefinition {
         }
 
         println("\nStarting Commander X16 emulator $emulator...")
-        val cmdline = listOf(emulator, "-scale", "2", "-run", "-prg", "${programNameWithPath}.prg") + extraArgs
+        val cmdline = listOf(emulator, "-scale", "2", "-rtc", "-run", "-prg", "${programNameWithPath}.prg") + extraArgs
         val processb = ProcessBuilder(cmdline).inheritIO()
         processb.environment()["PULSE_LATENCY_MSEC"] = "10"
         val process: Process = processb.start()
@@ -59,7 +62,7 @@ class CX16MachineDefinition: IMachineDefinition {
 
     override fun initializeMemoryAreas(compilerOptions: CompilationOptions) {
         zeropage = CX16Zeropage(compilerOptions)
-        golden = GoldenRam(compilerOptions, 0x0600u until 0x0800u)
+        golden = GoldenRam(compilerOptions, 0x0400u until 0x0800u)
     }
 
 }

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

@@ -40,16 +40,15 @@ class CX16Zeropage(options: CompilationOptions) : Zeropage(options) {
                 ZeropageType.DONTUSE -> {
                     free.clear() // don't use zeropage at all
                 }
-                else -> throw InternalCompilerException("for this machine target, zero page type 'floatsafe' is not available. ${options.zeropage}")
             }
 
-            val distictFree = free.distinct()
+            val distinctFree = free.distinct()
             free.clear()
-            free.addAll(distictFree)
+            free.addAll(distinctFree)
 
             removeReservedFromFreePool()
-
             allocateCx16VirtualRegisters()
+            retainAllowed()
         }
     }
 
@@ -58,12 +57,12 @@ class CX16Zeropage(options: CompilationOptions) : Zeropage(options) {
         // However, to be able for the compiler to "see" them as zero page 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[listOf("cx16", "r${reg}")]   = VarAllocation((2+reg*2).toUInt(), DataType.UWORD, 2)       // cx16.r0 .. cx16.r15
+            allocatedVariables["cx16.r${reg}"]   = VarAllocation((2+reg*2).toUInt(), DataType.UWORD, 2)       // cx16.r0 .. cx16.r15
-            allocatedVariables[listOf("cx16", "r${reg}s")]  = VarAllocation((2+reg*2).toUInt(), DataType.WORD, 2)        // cx16.r0s .. cx16.r15s
+            allocatedVariables["cx16.r${reg}s"]  = VarAllocation((2+reg*2).toUInt(), DataType.WORD, 2)        // cx16.r0s .. cx16.r15s
-            allocatedVariables[listOf("cx16", "r${reg}L")]  = VarAllocation((2+reg*2).toUInt(), DataType.UBYTE, 1)       // cx16.r0L .. cx16.r15L
+            allocatedVariables["cx16.r${reg}L"]  = VarAllocation((2+reg*2).toUInt(), DataType.UBYTE, 1)       // cx16.r0L .. cx16.r15L
-            allocatedVariables[listOf("cx16", "r${reg}H")]  = VarAllocation((3+reg*2).toUInt(), DataType.UBYTE, 1)       // cx16.r0H .. cx16.r15H
+            allocatedVariables["cx16.r${reg}H"]  = VarAllocation((3+reg*2).toUInt(), DataType.UBYTE, 1)       // cx16.r0H .. cx16.r15H
-            allocatedVariables[listOf("cx16", "r${reg}sL")] = VarAllocation((2+reg*2).toUInt(), DataType.BYTE, 1)        // cx16.r0sL .. cx16.r15sL
+            allocatedVariables["cx16.r${reg}sL"] = VarAllocation((2+reg*2).toUInt(), DataType.BYTE, 1)        // cx16.r0sL .. cx16.r15sL
-            allocatedVariables[listOf("cx16", "r${reg}sH")] = VarAllocation((3+reg*2).toUInt(), DataType.BYTE, 1)        // cx16.r0sH .. cx16.r15sH
+            allocatedVariables["cx16.r${reg}sH"] = VarAllocation((3+reg*2).toUInt(), DataType.BYTE, 1)        // cx16.r0sH .. cx16.r15sH
         }
     }
 }

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

@@ -0,0 +1,57 @@
+package prog8.code.target.pet
+
+import prog8.code.core.*
+import prog8.code.target.C64Target
+import prog8.code.target.cbm.Mflpt5
+import java.nio.file.Path
+
+
+class PETMachineDefinition: IMachineDefinition {
+
+    override val cpu = CpuType.CPU6502
+
+    override val FLOAT_MAX_POSITIVE = Mflpt5.FLOAT_MAX_POSITIVE
+    override val FLOAT_MAX_NEGATIVE = Mflpt5.FLOAT_MAX_NEGATIVE
+    override val FLOAT_MEM_SIZE = Mflpt5.FLOAT_MEM_SIZE
+    override val PROGRAM_LOAD_ADDRESS = 0x0401u
+
+    override val BSSHIGHRAM_START = 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 importLibs(compilerOptions: CompilationOptions, compilationTargetName: String): List<String> {
+        return if (compilerOptions.launcher == CbmPrgLauncherType.BASIC || compilerOptions.output == OutputType.PRG)
+            listOf("syslib")
+        else
+            emptyList()
+    }
+
+    override fun launchEmulator(selectedEmulator: Int, programNameWithPath: Path) {
+        if(selectedEmulator!=1) {
+            System.err.println("The pet target only supports the main emulator (Vice).")
+            return
+        }
+
+        println("\nStarting PET emulator...")
+        val viceMonlist = C64Target.viceMonListName(programNameWithPath.toString())
+        val cmdline = listOf("xpet", "-model", "4032", "-ramsize", "32", "-videosize", "40", "-silent", "-moncommands", viceMonlist,
+                "-autostartprgmode", "1", "-autostart-warp", "-autostart", "${programNameWithPath}.prg")
+        val processb = ProcessBuilder(cmdline).inheritIO()
+        val process=processb.start()
+        process.waitFor()
+    }
+
+    override fun isIOAddress(address: UInt): Boolean = address in 0xe800u..0xe8ffu
+
+    override fun initializeMemoryAreas(compilerOptions: CompilationOptions) {
+        zeropage = PETZeropage(compilerOptions)
+        // there's no golden ram.
+    }
+
+}

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

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

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

@@ -12,15 +12,23 @@ class VirtualMachineDefinition: IMachineDefinition {
 
     override val FLOAT_MAX_POSITIVE = Float.MAX_VALUE.toDouble()
     override val FLOAT_MAX_NEGATIVE = -Float.MAX_VALUE.toDouble()
-    override val FLOAT_MEM_SIZE = 4             // 32-bits floating point
+    override val FLOAT_MEM_SIZE = 8             // 64-bits double
     override val PROGRAM_LOAD_ADDRESS = 0u      // not actually used
 
-    override var ESTACK_LO = 0u                 // not actually used
+    override val BSSHIGHRAM_START = 0u          // not actually used
-    override var ESTACK_HI = 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) = TODO("float asm bytes from number")
+    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 importLibs(compilerOptions: CompilationOptions, compilationTargetName: String): List<String> {
         return listOf("syslib")
@@ -44,9 +52,24 @@ class VirtualMachineDefinition: IMachineDefinition {
 
     override fun isIOAddress(address: UInt): Boolean = false
 
-    override fun initializeMemoryAreas(compilerOptions: CompilationOptions) {}
+    override fun initializeMemoryAreas(compilerOptions: CompilationOptions) {
+        zeropage = VirtualZeropage(compilerOptions)
+    }
 }
 
 interface IVirtualMachineRunner {
     fun runProgram(irSource: String)
 }
+
+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")
+
+    override fun allocateCx16VirtualRegisters() { /* there is no actual zero page in this target to allocate thing in */ }
+}

codeGenCpu6502/build.gradle

@@ -3,6 +3,7 @@ plugins {
     id 'java'
     id 'application'
     id "org.jetbrains.kotlin.jvm"
+    id "io.kotest" version "0.3.9"
 }
 
 java {
@@ -25,22 +26,38 @@ compileTestKotlin {
 
 dependencies {
     implementation project(':codeCore')
-    implementation project(':compilerAst')
     implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8"
     // implementation "org.jetbrains.kotlin:kotlin-reflect"
-    implementation "com.michael-bull.kotlin-result:kotlin-result-jvm:1.1.16"
+    implementation "com.michael-bull.kotlin-result:kotlin-result-jvm:1.1.18"
 
+    testImplementation 'io.kotest:kotest-runner-junit5-jvm:5.8.0'
 }
 
 sourceSets {
     main {
         java {
-            srcDirs = ["${project.projectDir}/src"]
+            srcDir "${project.projectDir}/src"
         }
         resources {
-            srcDirs = ["${project.projectDir}/res"]
+            srcDir "${project.projectDir}/res"
+        }
+    }
+    test {
+        java {
+            srcDir "${project.projectDir}/test"
         }
     }
 }
 
-// note: there are no unit tests in this module!
+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

@@ -4,13 +4,15 @@
     <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="compilerAst" />
     <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" />
   </component>
 </module>

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

@@ -1,50 +1,49 @@
 package prog8.codegen.cpu6502
 
-import prog8.ast.Program
+import prog8.code.StConstant
-import prog8.ast.expressions.NumericLiteral
+import prog8.code.StMemVar
-import prog8.ast.statements.VarDecl
+import prog8.code.SymbolTable
-import prog8.ast.statements.VarDeclType
 import prog8.code.core.IMachineDefinition
 
 
 // note: see https://wiki.nesdev.org/w/index.php/6502_assembly_optimisations
 
 
-internal fun optimizeAssembly(lines: MutableList<String>, machine: IMachineDefinition, program: Program): Int {
+internal fun optimizeAssembly(lines: MutableList<String>, machine: IMachineDefinition, symbolTable: SymbolTable): Int {
 
     var numberOfOptimizations = 0
 
     var linesByFour = getLinesBy(lines, 4)
 
-    var mods = optimizeUselessStackByteWrites(linesByFour)
+    var mods = optimizeIncDec(linesByFour)
     if(mods.isNotEmpty()) {
         apply(mods, lines)
         linesByFour = getLinesBy(lines, 4)
         numberOfOptimizations++
     }
 
-    mods = optimizeIncDec(linesByFour)
+    mods = optimizeStoreLoadSame(linesByFour, machine, symbolTable)
     if(mods.isNotEmpty()) {
         apply(mods, lines)
         linesByFour = getLinesBy(lines, 4)
         numberOfOptimizations++
     }
 
-    mods = optimizeCmpSequence(linesByFour)
+    mods = optimizeJsrRtsAndOtherCombinations(linesByFour)
     if(mods.isNotEmpty()) {
         apply(mods, lines)
         linesByFour = getLinesBy(lines, 4)
         numberOfOptimizations++
     }
 
-    mods = optimizeStoreLoadSame(linesByFour, machine, program)
+    mods = optimizeUselessPushPopStack(linesByFour)
     if(mods.isNotEmpty()) {
         apply(mods, lines)
         linesByFour = getLinesBy(lines, 4)
         numberOfOptimizations++
     }
 
-    mods= optimizeJsrRtsAndOtherCombinations(linesByFour)
+    mods = optimizeUnneededTempvarInAdd(linesByFour)
     if(mods.isNotEmpty()) {
         apply(mods, lines)
         linesByFour = getLinesBy(lines, 4)
@@ -52,14 +51,14 @@ internal fun optimizeAssembly(lines: MutableList<String>, machine: IMachineDefin
     }
 
     var linesByFourteen = getLinesBy(lines, 14)
-    mods = optimizeSameAssignments(linesByFourteen, machine, program)
+    mods = optimizeSameAssignments(linesByFourteen, machine, symbolTable)
     if(mods.isNotEmpty()) {
         apply(mods, lines)
         linesByFourteen = getLinesBy(lines, 14)
         numberOfOptimizations++
     }
 
-    mods = optimizeSamePointerIndexing(linesByFourteen, machine, program)
+    mods = optimizeSamePointerIndexing(linesByFourteen)
     if(mods.isNotEmpty()) {
         apply(mods, lines)
         linesByFourteen = getLinesBy(lines, 14)
@@ -91,45 +90,11 @@ private fun getLinesBy(lines: MutableList<String>, windowSize: Int) =
 // all lines (that aren't empty or comments) in sliding windows of certain size
         lines.withIndex().filter { it.value.isNotBlank() && !it.value.trimStart().startsWith(';') }.windowed(windowSize, partialWindows = false)
 
-private fun optimizeCmpSequence(linesByFour: List<List<IndexedValue<String>>>): List<Modification> {
+private fun optimizeSameAssignments(
-    // when statement (on bytes) generates a sequence of:
+    linesByFourteen: List<List<IndexedValue<String>>>,
-    //	 lda  $ce01,x
+    machine: IMachineDefinition,
-    //	 cmp  #$20
+    symbolTable: SymbolTable
-    //	 beq  check_prog8_s72choice_32
+): List<Modification> {
-    //	 lda  $ce01,x
-    //	 cmp  #$21
-    //	 beq  check_prog8_s73choice_33
-    // the repeated lda can be removed
-    val mods = mutableListOf<Modification>()
-    for(lines in linesByFour) {
-        if(lines[0].value.trim()=="lda  P8ESTACK_LO+1,x" &&
-                lines[1].value.trim().startsWith("cmp ") &&
-                lines[2].value.trim().startsWith("beq ") &&
-                lines[3].value.trim()=="lda  P8ESTACK_LO+1,x") {
-            mods.add(Modification(lines[3].index, true, null)) // remove the second lda
-        }
-    }
-    return mods
-}
-
-private fun optimizeUselessStackByteWrites(linesByFour: List<List<IndexedValue<String>>>): List<Modification> {
-    // sta on stack, dex, inx, lda from stack -> eliminate this useless stack byte write
-    // this is a lot harder for word values because the instruction sequence varies.
-    val mods = mutableListOf<Modification>()
-    for(lines in linesByFour) {
-        if(lines[0].value.trim()=="sta  P8ESTACK_LO,x" &&
-                lines[1].value.trim()=="dex" &&
-                lines[2].value.trim()=="inx" &&
-                lines[3].value.trim()=="lda  P8ESTACK_LO,x") {
-            mods.add(Modification(lines[1].index, true, null))
-            mods.add(Modification(lines[2].index, true, null))
-            mods.add(Modification(lines[3].index, true, null))
-        }
-    }
-    return mods
-}
-
-private fun optimizeSameAssignments(linesByFourteen: List<List<IndexedValue<String>>>, machine: IMachineDefinition, program: Program): 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...
@@ -154,8 +119,8 @@ private fun optimizeSameAssignments(linesByFourteen: List<List<IndexedValue<Stri
             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, program)
+                val address1 = getAddressArg(first, symbolTable)
-                val address2 = getAddressArg(second, program)
+                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))
@@ -168,7 +133,7 @@ private fun optimizeSameAssignments(linesByFourteen: List<List<IndexedValue<Stri
             val secondvalue = third.substring(4)
             if(firstvalue==secondvalue) {
                 // lda value / sta ? / lda same-value / sta ?  -> remove second lda (third line)
-                val address = getAddressArg(first, program)
+                val address = getAddressArg(first, symbolTable)
                 if(address==null || !machine.isIOAddress(address))
                     mods.add(Modification(lines[2].index, true, null))
             }
@@ -251,7 +216,7 @@ private fun optimizeSameAssignments(linesByFourteen: List<List<IndexedValue<Stri
                 val thirdvalue = third.substring(4)
                 val fourthvalue = fourth.substring(4)
                 if(firstvalue==thirdvalue && secondvalue == fourthvalue) {
-                    val address = getAddressArg(first, program)
+                    val address = getAddressArg(first, symbolTable)
                     if(address==null || !machine.isIOAddress(address)) {
                         overlappingMods = true
                         mods.add(Modification(lines[2].index, true, null))
@@ -275,7 +240,7 @@ private fun optimizeSameAssignments(linesByFourteen: List<List<IndexedValue<Stri
                 val firstvalue = first.substring(4)
                 val thirdvalue = third.substring(4)
                 if(firstvalue==thirdvalue) {
-                    val address = getAddressArg(first, program)
+                    val address = getAddressArg(first, symbolTable)
                     if(address==null || !machine.isIOAddress(address)) {
                         overlappingMods = true
                         mods.add(Modification(lines[2].index, true, null))
@@ -295,7 +260,7 @@ private fun optimizeSameAssignments(linesByFourteen: List<List<IndexedValue<Stri
             val secondvalue = second.substring(4)
             val thirdvalue = third.substring(4)
             if(firstvalue==secondvalue && firstvalue==thirdvalue) {
-                val address = getAddressArg(first, program)
+                val address = getAddressArg(first, symbolTable)
                 if(address==null || !machine.isIOAddress(address)) {
                     overlappingMods = true
                     val reg2 = second[2]
@@ -308,26 +273,15 @@ private fun optimizeSameAssignments(linesByFourteen: List<List<IndexedValue<Stri
         /*
         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.
-        if(!overlappingMods && first.isStoreRegOrZero() && second.isStoreRegOrZero()) {
+        We can't see that here and would otherwise delete valid double stores.
-            if(first[2]==second[2]) {
+        */
-                val firstvalue = first.substring(4)
-                val secondvalue = second.substring(4)
-                if(firstvalue==secondvalue) {
-                    val address = getAddressArg(first, program)
-                    if(address==null || !machine.isIOAddress(address)) {
-                        overlappingMods = true
-                        mods.add(Modification(lines[0].index, true, null))
-                    }
-                }
-            }
-        }
     }
 
     return mods
 }
 
-private fun optimizeSamePointerIndexing(linesByFourteen: List<List<IndexedValue<String>>>, machine: IMachineDefinition, program: Program): List<Modification> {
+private fun optimizeSamePointerIndexing(linesByFourteen: List<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:
@@ -369,7 +323,11 @@ private fun optimizeSamePointerIndexing(linesByFourteen: List<List<IndexedValue<
     return mods
 }
 
-private fun optimizeStoreLoadSame(linesByFour: List<List<IndexedValue<String>>>, machine: IMachineDefinition, program: Program): List<Modification> {
+private fun optimizeStoreLoadSame(
+    linesByFour: List<List<IndexedValue<String>>>,
+    machine: IMachineDefinition,
+    symbolTable: SymbolTable
+): List<Modification> {
     // sta X + lda X,  sty X + ldy X,   stx X + ldx X  -> the second instruction can OFTEN be eliminated
     val mods = mutableListOf<Modification>()
     for (lines in linesByFour) {
@@ -397,7 +355,7 @@ private fun optimizeStoreLoadSame(linesByFour: List<List<IndexedValue<String>>>,
                 }
                 else {
                     // no branch instruction follows, we can remove the load instruction
-                    val address = getAddressArg(lines[2].value, program)
+                    val address = getAddressArg(lines[2].value, symbolTable)
                     address==null || !machine.isIOAddress(address)
                 }
 
@@ -423,15 +381,9 @@ private fun optimizeStoreLoadSame(linesByFour: List<List<IndexedValue<String>>>,
         } 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=="phx" && second=="ply") {
-            mods.add(Modification(lines[1].index, true, null))
-            mods.add(Modification(lines[2].index, false, "  txy"))
         } else if(first=="phy" && second=="pla") {
             mods.add(Modification(lines[1].index, true, null))
             mods.add(Modification(lines[2].index, false, "  tya"))
-        } else if(first=="phy" && second=="plx") {
-            mods.add(Modification(lines[1].index, true, null))
-            mods.add(Modification(lines[2].index, false, "  tyx"))
         }
     }
     return mods
@@ -439,7 +391,8 @@ private fun optimizeStoreLoadSame(linesByFour: List<List<IndexedValue<String>>>,
 
 private val identifierRegex = Regex("""^([a-zA-Z_$][a-zA-Z\d_\.$]*)""")
 
-private fun getAddressArg(line: String, program: Program): UInt? {
+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('$') -> loadArg.substring(1).toUIntOrNull(16)
@@ -450,15 +403,11 @@ private fun getAddressArg(line: String, program: Program): UInt? {
             val identMatch = identifierRegex.find(loadArg)
             if(identMatch!=null) {
                 val identifier = identMatch.value
-                val decl = program.toplevelModule.lookup(identifier.split(".")) as? VarDecl
+                when (val symbol = symbolTable.flat[identifier]) {
-                if(decl!=null) {
+                    is StConstant -> symbol.value.toUInt()
-                    when(decl.type){
+                    is StMemVar -> symbol.address
-                        VarDeclType.VAR -> null
+                    else -> null
-                        VarDeclType.CONST,
-                        VarDeclType.MEMORY -> (decl.value as NumericLiteral).number.toUInt()
-                    }
                 }
-                else null
             } else null
         }
         else -> loadArg.substring(1).toUIntOrNull()
@@ -524,3 +473,63 @@ private fun optimizeJsrRtsAndOtherCombinations(linesByFour: List<List<IndexedVal
     }
     return mods
 }
+
+private fun optimizeUselessPushPopStack(linesByFour: List<List<IndexedValue<String>>>): List<Modification> {
+    val mods = mutableListOf<Modification>()
+
+    fun optimize(register: Char, lines: List<IndexedValue<String>>) {
+        if(lines[0].value.trimStart().startsWith("ph$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)
+    }
+    return mods
+}
+
+private fun optimizeUnneededTempvarInAdd(linesByFour: List<List<IndexedValue<String>>>): List<Modification> {
+    // sequence:  sta  P8ZP_SCRATCH_XX  / lda  something / clc / adc  P8ZP_SCRATCH_XX
+    // this can be performed without the scratch variable:  clc  /  adc  something
+    val mods = mutableListOf<Modification>()
+
+    for(lines in linesByFour) {
+        val first = lines[0].value.trimStart()
+        val second = lines[1].value.trimStart()
+        val third = lines[2].value.trimStart()
+        val fourth = lines[3].value.trimStart()
+        if(first.startsWith("sta  P8ZP_SCRATCH_") && second.startsWith("lda") && third.startsWith("clc") && fourth.startsWith("adc  P8ZP_SCRATCH_") ) {
+            if(fourth.substring(4)==first.substring(4)) {
+                mods.add(Modification(lines[0].index, false, "    clc"))
+                mods.add(Modification(lines[1].index, false, "    adc  ${second.substring(3).trimStart()}"))
+                mods.add(Modification(lines[2].index, true, null))
+                mods.add(Modification(lines[3].index, true, null))
+            }
+        }
+    }
+
+    return mods
+}

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

@@ -1,61 +1,28 @@
 package prog8.codegen.cpu6502
 
-import prog8.ast.expressions.ArrayIndexedExpression
+import prog8.code.ast.PtAsmSub
-import prog8.ast.expressions.BuiltinFunctionCall
-import prog8.ast.expressions.Expression
-import prog8.ast.statements.Subroutine
 import prog8.code.core.Cx16VirtualRegisters
 import prog8.code.core.RegisterOrPair
-import prog8.code.core.RegisterOrStatusflag
 
 
-fun asmsub6502ArgsEvalOrder(sub: Subroutine): List<Int> {
+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 (X last), except A,
+    //  3) single CPU registers (order Y,X,A),
     //  4) CPU Carry status flag
-    //  5) the A register itself last   (so everything before it can use the accumulator without having to save its value)
+    val args = sub.parameters.withIndex()
-    val args = sub.parameters.zip(sub.asmParameterRegisters).withIndex()
+    val (cx16regs, args2) = args.partition { it.value.first.registerOrPair in Cx16VirtualRegisters }
-    val (cx16regs, args2) = args.partition { it.value.second.registerOrPair in Cx16VirtualRegisters }
     val pairedRegisters = arrayOf(RegisterOrPair.AX, RegisterOrPair.AY, RegisterOrPair.XY)
-    val (pairedRegs , args3) = args2.partition { it.value.second.registerOrPair in pairedRegisters }
+    val (pairedRegs , args3) = args2.partition { it.value.first.registerOrPair in pairedRegisters }
-    val (regsWithoutA, args4) = args3.partition { it.value.second.registerOrPair != RegisterOrPair.A }
+    val (singleRegs, rest) = args3.partition { it.value.first.registerOrPair != null }
-    val (regA, rest) = args4.partition { it.value.second.registerOrPair != null }
 
     cx16regs.forEach { order += it.index }
     pairedRegs.forEach { order += it.index }
-    regsWithoutA.forEach {
+    singleRegs.sortedBy { it.value.first.registerOrPair!!.asCpuRegister() }.asReversed().forEach { order += it.index }
-        if(it.value.second.registerOrPair != RegisterOrPair.X)
+    require(rest.all { it.value.first.registerOrPair==null && it.value.first.statusflag!=null})
-            order += it.index
-    }
-    regsWithoutA.firstOrNull { it.value.second.registerOrPair==RegisterOrPair.X } ?.let { order += it.index}
     rest.forEach { order += it.index }
-    regA.forEach { order += it.index }
     require(order.size==sub.parameters.size)
     return order
 }
-
-fun asmsub6502ArgsHaveRegisterClobberRisk(args: List<Expression>,
-                                                   paramRegisters: List<RegisterOrStatusflag>): Boolean {
-    fun isClobberRisk(expr: Expression): Boolean {
-        when (expr) {
-            is ArrayIndexedExpression -> {
-                return paramRegisters.any {
-                    it.registerOrPair in listOf(RegisterOrPair.Y, RegisterOrPair.AY, RegisterOrPair.XY)
-                }
-            }
-            is BuiltinFunctionCall -> {
-                if (expr.name == "lsb" || expr.name == "msb")
-                    return isClobberRisk(expr.args[0])
-                if (expr.name == "mkword")
-                    return isClobberRisk(expr.args[0]) && isClobberRisk(expr.args[1])
-                return !expr.isSimple
-            }
-            else -> return !expr.isSimple
-        }
-    }
-
-    return args.size>1 && args.any { isClobberRisk(it) }
-}

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

@@ -1,14 +1,8 @@
 package prog8.codegen.cpu6502
 
-import com.github.michaelbull.result.Ok
-import com.github.michaelbull.result.Result
-import com.github.michaelbull.result.mapError
-import prog8.ast.generatedLabelPrefix
 import prog8.code.core.*
-import java.io.File
+import prog8.code.target.C64Target
 import java.nio.file.Path
-import kotlin.io.path.Path
-import kotlin.io.path.isRegularFile
 
 
 internal class AssemblyProgram(
@@ -20,23 +14,28 @@ internal class AssemblyProgram(
     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("$name.bin")
-    private val viceMonListFile = outputDir.resolve(viceMonListName(name))
+    private val viceMonListFile = outputDir.resolve(C64Target.viceMonListName(name))
     private val listFile = outputDir.resolve("$name.list")
 
-    override fun assemble(options: CompilationOptions): Boolean {
+    override fun assemble(options: CompilationOptions, errors: IErrorReporter): Boolean {
 
         val assemblerCommand: List<String>
 
         when (compTarget.name) {
-            in setOf("c64", "c128", "cx16") -> {
+            in setOf("c64", "c128", "cx16", "pet32") -> {
                 // CBM machines .prg generation.
 
                 // add "-Wlong-branch"  to see warnings about conversion of branch instructions to jumps (default = do this silently)
                 val command = mutableListOf("64tass", "--ascii", "--case-sensitive", "--long-branch",
-                    "-Wall", "-Wno-strict-bool", "-Wno-shadow", // "-Werror",
+                    "-Wall", // "-Wno-strict-bool", "-Werror",
                     "--dump-labels", "--vice-labels", "--labels=$viceMonListFile", "--no-monitor"
                 )
 
+                if(options.warnSymbolShadowing)
+                    command.add("-Wshadow")
+                else
+                    command.add("-Wno-shadow")
+
                 if(options.asmQuiet)
                     command.add("--quiet")
 
@@ -63,12 +62,17 @@ internal class AssemblyProgram(
             "atari" -> {
                 // Atari800XL .xex generation.
 
-                // TODO are these options okay?
+                // TODO are these options okay for atari?
                 val command = mutableListOf("64tass", "--ascii", "--case-sensitive", "--long-branch",
-                    "-Wall", "-Wno-strict-bool", "-Wno-shadow", // "-Werror",
+                    "-Wall", // "-Werror", "-Wno-strict-bool"
                     "--no-monitor"
                 )
 
+                if(options.warnSymbolShadowing)
+                    command.add("-Wshadow")
+                else
+                    command.add("-Wno-shadow")
+
                 if(options.asmQuiet)
                     command.add("--quiet")
 
@@ -104,7 +108,7 @@ internal class AssemblyProgram(
     }
 
     private fun removeGeneratedLabelsFromMonlist() {
-        val pattern = Regex("""al (\w+) \S+${generatedLabelPrefix}.+?""")
+        val pattern = Regex("""al (\w+) \S+prog8_label_.+?""")
         val lines = viceMonListFile.toFile().readLines()
         viceMonListFile.toFile().outputStream().bufferedWriter().use {
             for (line in lines) {
@@ -124,24 +128,9 @@ internal class AssemblyProgram(
                 breakpoints.add("break \$" + match.groupValues[1])
         }
         val num = breakpoints.size
-        breakpoints.add(0, "; vice monitor breakpoint list now follows")
+        breakpoints.add(0, "; breakpoint list now follows")
         breakpoints.add(1, "; $num breakpoints have been defined")
         breakpoints.add(2, "del")
         viceMonListFile.toFile().appendText(breakpoints.joinToString("\n") + "\n")
     }
 }
-
-
-internal fun loadAsmIncludeFile(filename: String, source: SourceCode): Result<String, NoSuchFileException> {
-    return if (filename.startsWith(SourceCode.libraryFilePrefix)) {
-        return com.github.michaelbull.result.runCatching {
-            SourceCode.Resource("/prog8lib/${filename.substring(SourceCode.libraryFilePrefix.length)}").text
-        }.mapError { NoSuchFileException(File(filename)) }
-    } else {
-        val sib = Path(source.origin).resolveSibling(filename)
-        if (sib.isRegularFile())
-            Ok(SourceCode.File(sib).text)
-        else
-            Ok(SourceCode.File(Path(filename)).text)
-    }
-}

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

@@ -1,918 +0,0 @@
-package prog8.codegen.cpu6502
-
-import prog8.ast.Program
-import prog8.ast.expressions.*
-import prog8.code.core.*
-import kotlin.math.absoluteValue
-
-internal class ExpressionsAsmGen(private val program: Program,
-                                 private val asmgen: AsmGen,
-                                 private val allocator: VariableAllocator) {
-
-    @Deprecated("avoid calling this as it generates slow evalstack based code")
-    internal fun translateExpression(expression:Expression) {
-        if (this.asmgen.options.slowCodegenWarnings) {
-            asmgen.errors.warn("slow stack evaluation used for expression $expression", expression.position)
-        }
-        translateExpressionInternal(expression)
-    }
-
-
-    // the rest of the methods are all PRIVATE
-
-
-    private fun translateExpressionInternal(expression: Expression) {
-
-        when(expression) {
-            is PrefixExpression -> translateExpression(expression)
-            is BinaryExpression -> translateExpression(expression)
-            is ArrayIndexedExpression -> translateExpression(expression)
-            is TypecastExpression -> translateExpression(expression)
-            is AddressOf -> translateExpression(expression)
-            is DirectMemoryRead -> asmgen.translateDirectMemReadExpressionToRegAorStack(expression, true)
-            is NumericLiteral -> translateExpression(expression)
-            is IdentifierReference -> translateExpression(expression)
-            is FunctionCallExpression -> translateFunctionCallResultOntoStack(expression)
-            is BuiltinFunctionCall -> asmgen.translateBuiltinFunctionCallExpression(expression, true, null)
-            is ContainmentCheck -> throw AssemblyError("containment check as complex expression value is not supported")
-            is ArrayLiteral, is StringLiteral -> throw AssemblyError("no asm gen for string/array literal value assignment - should have been replaced by a variable")
-            is RangeExpression -> throw AssemblyError("range expression should have been changed into array values")
-            is CharLiteral -> throw AssemblyError("charliteral should have been replaced by ubyte using certain encoding")
-            else -> TODO("missing expression asmgen for $expression")
-        }
-    }
-
-    private fun translateFunctionCallResultOntoStack(call: FunctionCallExpression) {
-        // only for use in nested expression evaluation
-
-        val sub = call.target.targetSubroutine(program)!!
-        asmgen.saveXbeforeCall(call)
-        asmgen.translateFunctionCall(call, true)
-        if(sub.regXasResult()) {
-            // store the return value in X somewhere that we can access again below
-            asmgen.out("  stx  P8ZP_SCRATCH_REG")
-        }
-        asmgen.restoreXafterCall(call)
-
-        val returns = sub.returntypes.zip(sub.asmReturnvaluesRegisters)
-        for ((_, reg) in returns) {
-            // result value is in cpu or status registers, put it on the stack instead (as we're evaluating an expression tree)
-            if (reg.registerOrPair != null) {
-                when (reg.registerOrPair!!) {
-                    RegisterOrPair.A -> asmgen.out("  sta  P8ESTACK_LO,x |  dex")
-                    RegisterOrPair.Y -> asmgen.out("  tya |  sta  P8ESTACK_LO,x |  dex")
-                    RegisterOrPair.AY -> asmgen.out("  sta  P8ESTACK_LO,x |  tya |  sta  P8ESTACK_HI,x |  dex")
-                    RegisterOrPair.X -> asmgen.out("  lda  P8ZP_SCRATCH_REG |  sta  P8ESTACK_LO,x |  dex")
-                    RegisterOrPair.AX -> asmgen.out("  sta  P8ESTACK_LO,x |  lda  P8ZP_SCRATCH_REG |  sta  P8ESTACK_HI,x |  dex")
-                    RegisterOrPair.XY -> asmgen.out("  tya |  sta  P8ESTACK_HI,x |  lda  P8ZP_SCRATCH_REG |  sta  P8ESTACK_LO,x |  dex")
-                    RegisterOrPair.FAC1 -> asmgen.out("  jsr  floats.push_fac1")
-                    RegisterOrPair.FAC2 -> asmgen.out("  jsr  floats.push_fac2")
-                    RegisterOrPair.R0,
-                    RegisterOrPair.R1,
-                    RegisterOrPair.R2,
-                    RegisterOrPair.R3,
-                    RegisterOrPair.R4,
-                    RegisterOrPair.R5,
-                    RegisterOrPair.R6,
-                    RegisterOrPair.R7,
-                    RegisterOrPair.R8,
-                    RegisterOrPair.R9,
-                    RegisterOrPair.R10,
-                    RegisterOrPair.R11,
-                    RegisterOrPair.R12,
-                    RegisterOrPair.R13,
-                    RegisterOrPair.R14,
-                    RegisterOrPair.R15 -> {
-                        asmgen.out(
-                            """
-                            lda  cx16.${reg.registerOrPair.toString().lowercase()}
-                            sta  P8ESTACK_LO,x
-                            lda  cx16.${reg.registerOrPair.toString().lowercase()}+1
-                            sta  P8ESTACK_HI,x
-                            dex
-                        """)
-                    }
-                }
-            } else when(reg.statusflag) {
-                Statusflag.Pc -> {
-                    asmgen.out("""
-                        lda  #0
-                        rol  a
-                        sta  P8ESTACK_LO,x
-                        dex""")
-                }
-                Statusflag.Pz -> {
-                    asmgen.out("""
-                        beq  +
-                        lda  #0
-                        beq  ++
-+                           lda  #1
-+                           sta  P8ESTACK_LO,x
-                        dex""")
-                }
-                Statusflag.Pv -> {
-                    asmgen.out("""
-                        bvs  +
-                        lda  #0
-                        beq  ++
-+                           lda  #1
-+                           sta  P8ESTACK_LO,x
-                        dex""")
-                }
-                Statusflag.Pn -> {
-                    asmgen.out("""
-                        bmi  +
-                        lda  #0
-                        beq  ++
-+                           lda  #1
-+                           sta  P8ESTACK_LO,x
-                        dex""")
-                }
-                null -> {}
-            }
-        }
-    }
-
-    private fun translateExpression(typecast: TypecastExpression) {
-        translateExpressionInternal(typecast.expression)
-        when(typecast.expression.inferType(program).getOr(DataType.UNDEFINED)) {
-            DataType.UBYTE, DataType.BOOL -> {
-                when(typecast.type) {
-                    DataType.UBYTE, DataType.BYTE -> {}
-                    DataType.UWORD, DataType.WORD -> {
-                        if(asmgen.isTargetCpu(CpuType.CPU65c02))
-                            asmgen.out("  stz  P8ESTACK_HI+1,x")
-                        else
-                            asmgen.out("  lda  #0  |  sta  P8ESTACK_HI+1,x")
-                    }
-                    DataType.FLOAT -> asmgen.out(" jsr  floats.stack_ub2float")
-                    in PassByReferenceDatatypes -> throw AssemblyError("cannot cast to a pass-by-reference datatype")
-                    else -> throw AssemblyError("weird type")
-                }
-            }
-            DataType.BYTE -> {
-                when(typecast.type) {
-                    DataType.UBYTE, DataType.BYTE -> {}
-                    DataType.UWORD, DataType.WORD -> asmgen.signExtendStackLsb(DataType.BYTE)
-                    DataType.FLOAT -> asmgen.out(" jsr  floats.stack_b2float")
-                    in PassByReferenceDatatypes -> throw AssemblyError("cannot cast to a pass-by-reference datatype")
-                    else -> throw AssemblyError("weird type")
-                }
-            }
-            DataType.UWORD -> {
-                when(typecast.type) {
-                    DataType.BYTE, DataType.UBYTE -> {}
-                    DataType.WORD, DataType.UWORD -> {}
-                    DataType.FLOAT -> asmgen.out(" jsr  floats.stack_uw2float")
-                    in PassByReferenceDatatypes -> throw AssemblyError("cannot cast to a pass-by-reference datatype")
-                    else -> throw AssemblyError("weird type")
-                }
-            }
-            DataType.WORD -> {
-                when(typecast.type) {
-                    DataType.BYTE, DataType.UBYTE -> {}
-                    DataType.WORD, DataType.UWORD -> {}
-                    DataType.FLOAT -> asmgen.out(" jsr  floats.stack_w2float")
-                    in PassByReferenceDatatypes -> throw AssemblyError("cannot cast to a pass-by-reference datatype")
-                    else -> throw AssemblyError("weird type")
-                }
-            }
-            DataType.FLOAT -> {
-                when(typecast.type) {
-                    DataType.UBYTE -> asmgen.out(" jsr  floats.stack_float2uw")
-                    DataType.BYTE -> asmgen.out(" jsr  floats.stack_float2w")
-                    DataType.UWORD -> asmgen.out(" jsr  floats.stack_float2uw")
-                    DataType.WORD -> asmgen.out(" jsr  floats.stack_float2w")
-                    DataType.FLOAT -> {}
-                    in PassByReferenceDatatypes -> throw AssemblyError("cannot cast to a pass-by-reference datatype")
-                    else -> throw AssemblyError("weird type")
-                }
-            }
-            DataType.STR -> {
-                if (typecast.type != DataType.UWORD && typecast.type == DataType.STR)
-                    throw AssemblyError("cannot typecast a string into another incompatitble type")
-            }
-            in PassByReferenceDatatypes -> throw AssemblyError("cannot cast pass-by-reference value into another type")
-            else -> throw AssemblyError("weird type")
-        }
-    }
-
-    private fun translateExpression(expr: AddressOf) {
-        val name = asmgen.asmVariableName(expr.identifier)
-        asmgen.out("  lda  #<$name |  sta  P8ESTACK_LO,x |  lda  #>$name  |  sta  P8ESTACK_HI,x  | dex")
-    }
-
-    private fun translateExpression(expr: NumericLiteral) {
-        when(expr.type) {
-            DataType.UBYTE, DataType.BYTE -> asmgen.out(" lda  #${expr.number.toHex()}  | sta  P8ESTACK_LO,x  | dex")
-            DataType.UWORD, DataType.WORD -> asmgen.out("""
-                lda  #<${expr.number.toHex()}
-                sta  P8ESTACK_LO,x
-                lda  #>${expr.number.toHex()}
-                sta  P8ESTACK_HI,x
-                dex
-            """)
-            DataType.FLOAT -> {
-                val floatConst = allocator.getFloatAsmConst(expr.number)
-                asmgen.out(" lda  #<$floatConst |  ldy  #>$floatConst |  jsr  floats.push_float")
-            }
-            else -> throw AssemblyError("weird type")
-        }
-    }
-
-    private fun translateExpression(expr: IdentifierReference) {
-        val varname = asmgen.asmVariableName(expr)
-        when(expr.inferType(program).getOr(DataType.UNDEFINED)) {
-            DataType.UBYTE, DataType.BYTE -> {
-                asmgen.out("  lda  $varname  |  sta  P8ESTACK_LO,x  |  dex")
-            }
-            DataType.UWORD, DataType.WORD -> {
-                asmgen.out("  lda  $varname  |  sta  P8ESTACK_LO,x  |  lda  $varname+1 |  sta  P8ESTACK_HI,x |  dex")
-            }
-            DataType.FLOAT -> {
-                asmgen.out(" lda  #<$varname |  ldy  #>$varname|  jsr  floats.push_float")
-            }
-            in IterableDatatypes -> {
-                asmgen.out("  lda  #<$varname  |  sta  P8ESTACK_LO,x  |  lda  #>$varname |  sta  P8ESTACK_HI,x |  dex")
-            }
-            else -> throw AssemblyError("stack push weird variable type $expr")
-        }
-    }
-
-    private fun translateExpression(expr: BinaryExpression) {
-        // Uses evalstack to evaluate the given expression.
-        // TODO we're slowly reducing the number of places where this is called and instead replace that by more efficient assignment-form code (using temp var or register for instance).
-        val leftIDt = expr.left.inferType(program)
-        val rightIDt = expr.right.inferType(program)
-        if(!leftIDt.isKnown || !rightIDt.isKnown)
-            throw AssemblyError("can't infer type of both expression operands")
-
-        val leftDt = leftIDt.getOrElse { throw AssemblyError("unknown dt") }
-        val rightDt = rightIDt.getOrElse { throw AssemblyError("unknown dt") }
-        // see if we can apply some optimized routines
-        when(expr.operator) {
-            "+" -> {
-                if(leftDt in IntegerDatatypes && rightDt in IntegerDatatypes) {
-                    val leftVal = expr.left.constValue(program)?.number?.toInt()
-                    val rightVal = expr.right.constValue(program)?.number?.toInt()
-                    if (leftVal!=null && leftVal in -4..4) {
-                        translateExpressionInternal(expr.right)
-                        if(rightDt in ByteDatatypes) {
-                            val incdec = if(leftVal<0) "dec" else "inc"
-                            repeat(leftVal.absoluteValue) {
-                                asmgen.out("  $incdec  P8ESTACK_LO+1,x")
-                            }
-                        } else {
-                            // word
-                            if(leftVal<0) {
-                                repeat(leftVal.absoluteValue) {
-                                    asmgen.out("""
-                                        lda  P8ESTACK_LO+1,x
-                                        bne  +
-                                        dec  P8ESTACK_HI+1,x
-+                                       dec  P8ESTACK_LO+1,x""")
-                                }
-                            } else {
-                                repeat(leftVal) {
-                                    asmgen.out("""
-                                        inc  P8ESTACK_LO+1,x
-                                        bne  +
-                                        inc  P8ESTACK_HI+1,x
-+""")
-                                }
-                            }
-                        }
-                        return
-                    }
-                    else if (rightVal!=null && rightVal in -4..4)
-                    {
-                        translateExpressionInternal(expr.left)
-                        if(leftDt in ByteDatatypes) {
-                            val incdec = if(rightVal<0) "dec" else "inc"
-                            repeat(rightVal.absoluteValue) {
-                                asmgen.out("  $incdec  P8ESTACK_LO+1,x")
-                            }
-                        } else {
-                            // word
-                            if(rightVal<0) {
-                                repeat(rightVal.absoluteValue) {
-                                    asmgen.out("""
-                                        lda  P8ESTACK_LO+1,x
-                                        bne  +
-                                        dec  P8ESTACK_HI+1,x
-+                                       dec  P8ESTACK_LO+1,x""")
-                                }
-                            } else {
-                                repeat(rightVal) {
-                                    asmgen.out("""
-                                        inc  P8ESTACK_LO+1,x
-                                        bne  +
-                                        inc  P8ESTACK_HI+1,x
-+""")
-                                }
-                            }
-                        }
-                        return
-                    }
-                }
-            }
-            "-" -> {
-                if(leftDt in IntegerDatatypes && rightDt in IntegerDatatypes) {
-                    val rightVal = expr.right.constValue(program)?.number?.toInt()
-                    if (rightVal!=null && rightVal in -4..4)
-                    {
-                        translateExpressionInternal(expr.left)
-                        if(leftDt in ByteDatatypes) {
-                            val incdec = if(rightVal<0) "inc" else "dec"
-                            repeat(rightVal.absoluteValue) {
-                                asmgen.out("  $incdec  P8ESTACK_LO+1,x")
-                            }
-                        } else {
-                            // word
-                            if(rightVal>0) {
-                                repeat(rightVal.absoluteValue) {
-                                    asmgen.out("""
-                                        lda  P8ESTACK_LO+1,x
-                                        bne  +
-                                        dec  P8ESTACK_HI+1,x
-+                                       dec  P8ESTACK_LO+1,x""")
-                                }
-                            } else {
-                                repeat(rightVal) {
-                                    asmgen.out("""
-                                        inc  P8ESTACK_LO+1,x
-                                        bne  +
-                                        inc  P8ESTACK_HI+1,x
-+""")
-                                }
-                            }
-                        }
-                        return
-                    }
-                }
-            }
-            ">>" -> {
-                val amount = expr.right.constValue(program)?.number?.toInt()
-                if(amount!=null) {
-                    translateExpressionInternal(expr.left)
-                    when (leftDt) {
-                        DataType.UBYTE -> {
-                            if (amount <= 2)
-                                repeat(amount) { asmgen.out(" lsr  P8ESTACK_LO+1,x") }
-                            else {
-                                asmgen.out(" lda  P8ESTACK_LO+1,x")
-                                repeat(amount) { asmgen.out(" lsr  a") }
-                                asmgen.out(" sta  P8ESTACK_LO+1,x")
-                            }
-                        }
-                        DataType.BYTE -> {
-                            if (amount <= 2)
-                                repeat(amount) { asmgen.out(" lda  P8ESTACK_LO+1,x |  asl  a |  ror  P8ESTACK_LO+1,x") }
-                            else {
-                                asmgen.out(" lda  P8ESTACK_LO+1,x |  sta  P8ZP_SCRATCH_B1")
-                                repeat(amount) { asmgen.out(" asl  a |  ror  P8ZP_SCRATCH_B1 |  lda  P8ZP_SCRATCH_B1") }
-                                asmgen.out(" sta  P8ESTACK_LO+1,x")
-                            }
-                        }
-                        DataType.UWORD -> {
-                            if(amount>=16) {
-                                if(asmgen.isTargetCpu(CpuType.CPU65c02))
-                                    asmgen.out("  stz  P8ESTACK_LO+1,x |  stz  P8ESTACK_HI+1,x")
-                                else
-                                    asmgen.out("  lda  #0 |  sta  P8ESTACK_LO+1,x |  sta  P8ESTACK_HI+1,x")
-                                return
-                            }
-                            var left = amount
-                            while (left >= 7) {
-                                asmgen.out(" jsr  math.shift_right_uw_7")
-                                left -= 7
-                            }
-                            if (left in 0..2)
-                                repeat(left) { asmgen.out(" lsr  P8ESTACK_HI+1,x |  ror  P8ESTACK_LO+1,x") }
-                            else
-                                asmgen.out(" jsr  math.shift_right_uw_$left")
-                        }
-                        DataType.WORD -> {
-                            if(amount>=16) {
-                                asmgen.out("""
-                                    lda  P8ESTACK_HI+1,x
-                                    bmi  +
-                                    lda  #0
-                                    sta  P8ESTACK_LO+1,x
-                                    sta  P8ESTACK_HI+1,x
-                                    beq  ++
-+                                   lda  #255
-                                    sta  P8ESTACK_LO+1,x
-                                    sta  P8ESTACK_HI+1,x
-+""")
-                                return
-                            }
-                            var left = amount
-                            while (left >= 7) {
-                                asmgen.out(" jsr  math.shift_right_w_7")
-                                left -= 7
-                            }
-                            if (left in 0..2)
-                                repeat(left) { asmgen.out(" lda  P8ESTACK_HI+1,x |  asl  a  |  ror  P8ESTACK_HI+1,x |  ror  P8ESTACK_LO+1,x") }
-                            else
-                                asmgen.out(" jsr  math.shift_right_w_$left")
-                        }
-                        else -> throw AssemblyError("weird type")
-                    }
-                    return
-                }
-            }
-            "<<" -> {
-                val amount = expr.right.constValue(program)?.number?.toInt()
-                if(amount!=null) {
-                    translateExpressionInternal(expr.left)
-                    if (leftDt in ByteDatatypes) {
-                        if (amount <= 2)
-                            repeat(amount) { asmgen.out("  asl  P8ESTACK_LO+1,x") }
-                        else {
-                            asmgen.out("  lda  P8ESTACK_LO+1,x")
-                            repeat(amount) { asmgen.out("  asl  a") }
-                            asmgen.out("  sta  P8ESTACK_LO+1,x")
-                        }
-                    } else {
-                        var left = amount
-                        while (left >= 7) {
-                            asmgen.out(" jsr  math.shift_left_w_7")
-                            left -= 7
-                        }
-                        if (left in 0..2)
-                            repeat(left) { asmgen.out("  asl  P8ESTACK_LO+1,x |  rol  P8ESTACK_HI+1,x") }
-                        else
-                            asmgen.out(" jsr  math.shift_left_w_$left")
-                    }
-                    return
-                }
-            }
-            "*" -> {
-                if(leftDt in IntegerDatatypes && rightDt in IntegerDatatypes) {
-                    val leftVar = expr.left as? IdentifierReference
-                    val rightVar = expr.right as? IdentifierReference
-                    if(leftVar!=null && rightVar!=null && leftVar==rightVar)
-                        return translateSquared(leftVar, leftDt)
-                }
-
-                val value = expr.right.constValue(program)
-                if(value!=null) {
-                    if(rightDt in IntegerDatatypes) {
-                        val amount = value.number.toInt()
-                        if(amount==2) {
-                            // optimize x*2 common case
-                            translateExpressionInternal(expr.left)
-                            if(leftDt in ByteDatatypes) {
-                                asmgen.out("  asl  P8ESTACK_LO+1,x")
-                            } else {
-                                asmgen.out("  asl  P8ESTACK_LO+1,x |  rol  P8ESTACK_HI+1,x")
-                            }
-                            return
-                        }
-                        when(rightDt) {
-                            DataType.UBYTE -> {
-                                if(amount in asmgen.optimizedByteMultiplications) {
-                                    translateExpressionInternal(expr.left)
-                                    asmgen.out(" jsr  math.stack_mul_byte_$amount")
-                                    return
-                                }
-                            }
-                            DataType.BYTE -> {
-                                if(amount in asmgen.optimizedByteMultiplications) {
-                                    translateExpressionInternal(expr.left)
-                                    asmgen.out(" jsr  math.stack_mul_byte_$amount")
-                                    return
-                                }
-                                if(amount.absoluteValue in asmgen.optimizedByteMultiplications) {
-                                    translateExpressionInternal(expr.left)
-                                    asmgen.out(" jsr  prog8_lib.neg_b |  jsr  math.stack_mul_byte_${amount.absoluteValue}")
-                                    return
-                                }
-                            }
-                            DataType.UWORD -> {
-                                if(amount in asmgen.optimizedWordMultiplications) {
-                                    translateExpressionInternal(expr.left)
-                                    asmgen.out(" jsr  math.stack_mul_word_$amount")
-                                    return
-                                }
-                            }
-                            DataType.WORD -> {
-                                if(amount in asmgen.optimizedWordMultiplications) {
-                                    translateExpressionInternal(expr.left)
-                                    asmgen.out(" jsr  math.stack_mul_word_$amount")
-                                    return
-                                }
-                                if(amount.absoluteValue in asmgen.optimizedWordMultiplications) {
-                                    translateExpressionInternal(expr.left)
-                                    asmgen.out(" jsr  prog8_lib.neg_w |  jsr  math.stack_mul_word_${amount.absoluteValue}")
-                                    return
-                                }
-                            }
-                            else -> {}
-                        }
-                    }
-                }
-            }
-            "/" -> {
-                if(leftDt in IntegerDatatypes && rightDt in IntegerDatatypes) {
-                    val rightVal = expr.right.constValue(program)?.number?.toInt()
-                    if(rightVal!=null && rightVal==2) {
-                        translateExpressionInternal(expr.left)
-                        when (leftDt) {
-                            DataType.UBYTE -> {
-                                asmgen.out("  lsr  P8ESTACK_LO+1,x")
-                            }
-                            DataType.UWORD -> {
-                                asmgen.out("  lsr  P8ESTACK_HI+1,x |  ror  P8ESTACK_LO+1,x")
-                            }
-                            DataType.BYTE -> {
-                                // signed divide using shift needs adjusting of negative value to get correct rounding towards zero
-                                asmgen.out("""
-                                    lda  P8ESTACK_LO+1,x
-                                    bpl  +
-                                    inc  P8ESTACK_LO+1,x
-                                    lda  P8ESTACK_LO+1,x
-+                                   asl  a
-                                    ror  P8ESTACK_LO+1,x""")
-                            }
-                            DataType.WORD -> {
-                                // signed divide using shift needs adjusting of negative value to get correct rounding towards zero
-                                asmgen.out("""
-                                    lda  P8ESTACK_HI+1,x
-                                    bpl  ++
-                                    inc  P8ESTACK_LO+1,x
-                                    bne  +
-                                    inc  P8ESTACK_HI+1,x
-+                                   lda  P8ESTACK_HI+1,x
-+                                   asl  a
-                                    ror  P8ESTACK_HI+1,x
-                                    ror  P8ESTACK_LO+1,x""")
-                            }
-                            else -> throw AssemblyError("weird dt")
-                        }
-                        return
-                    }
-                }
-            }
-            in ComparisonOperators -> {
-                if(leftDt in NumericDatatypes && rightDt in NumericDatatypes) {
-                    val rightVal = expr.right.constValue(program)?.number
-                    if(rightVal==0.0)
-                        return translateComparisonWithZero(expr.left, leftDt, expr.operator)
-                }
-            }
-        }
-
-        if((leftDt in ByteDatatypes && rightDt !in ByteDatatypes)
-                || (leftDt in WordDatatypes && rightDt !in WordDatatypes))
-            throw AssemblyError("binary operator ${expr.operator} left/right dt not identical")
-
-        if(leftDt==DataType.STR && rightDt==DataType.STR && expr.operator in ComparisonOperators) {
-            translateCompareStrings(expr.left, expr.operator, expr.right)
-        }
-        else {
-            // the general, non-optimized cases  TODO optimize more cases.... (or one day just don't use the evalstack at all anymore)
-            translateExpressionInternal(expr.left)
-            translateExpressionInternal(expr.right)
-            when (leftDt) {
-                in ByteDatatypes -> translateBinaryOperatorBytes(expr.operator, leftDt)
-                in WordDatatypes -> translateBinaryOperatorWords(expr.operator, leftDt)
-                DataType.FLOAT -> translateBinaryOperatorFloats(expr.operator)
-                else -> throw AssemblyError("non-numerical datatype")
-            }
-        }
-    }
-
-    private fun translateComparisonWithZero(expr: Expression, dt: DataType, operator: String) {
-        if(expr.isSimple) {
-            if(operator=="!=") {
-                when (dt) {
-                    in ByteDatatypes -> {
-                        asmgen.assignExpressionToRegister(expr, RegisterOrPair.A, dt == DataType.BYTE)
-                        asmgen.out("""
-                            beq  +
-                            lda  #1
-+                           sta  P8ESTACK_LO,x
-                            dex""")
-                        return
-                    }
-                    in WordDatatypes -> {
-                        asmgen.assignExpressionToRegister(expr, RegisterOrPair.AY, dt == DataType.WORD)
-                        asmgen.out("""
-                            sty  P8ZP_SCRATCH_B1 
-                            ora  P8ZP_SCRATCH_B1
-                            beq  +
-                            lda  #1
-+                           sta  P8ESTACK_LO,x
-                            dex""")
-                        return
-                    }
-                    DataType.FLOAT -> {
-                        asmgen.assignExpressionToRegister(expr, RegisterOrPair.FAC1, true)
-                        asmgen.out("""
-                            jsr  floats.SIGN
-                            sta  P8ESTACK_LO,x
-                            dex""")
-                        return
-                    }
-                    else -> {}
-                }
-            }
-            /* operator == is not worth it to special case, the code is mostly larger */
-        }
-        translateExpressionInternal(expr)
-        when(operator) {
-            "==" -> {
-                when(dt) {
-                    DataType.UBYTE, DataType.BYTE -> asmgen.out("  jsr  prog8_lib.equalzero_b")
-                    DataType.UWORD, DataType.WORD -> asmgen.out("  jsr  prog8_lib.equalzero_w")
-                    DataType.FLOAT -> asmgen.out("  jsr  floats.equal_zero")
-                    else -> throw AssemblyError("wrong dt")
-                }
-            }
-            "!=" -> {
-                when(dt) {
-                    DataType.UBYTE, DataType.BYTE -> asmgen.out("  jsr  prog8_lib.notequalzero_b")
-                    DataType.UWORD, DataType.WORD -> asmgen.out("  jsr  prog8_lib.notequalzero_w")
-                    DataType.FLOAT -> asmgen.out("  jsr  floats.notequal_zero")
-                    else -> throw AssemblyError("wrong dt")
-                }
-            }
-            "<" -> {
-                if(dt==DataType.UBYTE || dt==DataType.UWORD)
-                    return translateExpressionInternal(NumericLiteral.fromBoolean(false, expr.position))
-                when(dt) {
-                    DataType.BYTE -> asmgen.out("  jsr  prog8_lib.lesszero_b")
-                    DataType.WORD -> asmgen.out("  jsr  prog8_lib.lesszero_w")
-                    DataType.FLOAT -> asmgen.out("  jsr  floats.less_zero")
-                    else -> throw AssemblyError("wrong dt")
-                }
-            }
-            ">" -> {
-                when(dt) {
-                    DataType.UBYTE -> asmgen.out("  jsr  prog8_lib.greaterzero_ub")
-                    DataType.BYTE -> asmgen.out("  jsr  prog8_lib.greaterzero_sb")
-                    DataType.UWORD -> asmgen.out("  jsr  prog8_lib.greaterzero_uw")
-                    DataType.WORD -> asmgen.out("  jsr  prog8_lib.greaterzero_sw")
-                    DataType.FLOAT -> asmgen.out("  jsr  floats.greater_zero")
-                    else -> throw AssemblyError("wrong dt")
-                }
-            }
-            "<=" -> {
-                when(dt) {
-                    DataType.UBYTE -> asmgen.out("  jsr  prog8_lib.equalzero_b")
-                    DataType.BYTE -> asmgen.out("  jsr  prog8_lib.lessequalzeros_b")
-                    DataType.UWORD -> asmgen.out("  jsr  prog8_lib.equalzero_w")
-                    DataType.WORD -> asmgen.out("  jsr  prog8_lib.lessequalzero_sw")
-                    DataType.FLOAT -> asmgen.out("  jsr  floats.lessequal_zero")
-                    else -> throw AssemblyError("wrong dt")
-                }
-            }
-            ">=" -> {
-                if(dt==DataType.UBYTE || dt==DataType.UWORD)
-                    return translateExpressionInternal(NumericLiteral.fromBoolean(true, expr.position))
-                when(dt) {
-                    DataType.BYTE -> asmgen.out("  jsr  prog8_lib.greaterequalzero_sb")
-                    DataType.WORD -> asmgen.out("  jsr  prog8_lib.greaterequalzero_sw")
-                    DataType.FLOAT -> asmgen.out("  jsr  floats.greaterequal_zero")
-                    else -> throw AssemblyError("wrong dt")
-                }
-            }
-            else -> throw AssemblyError("invalid comparison operator")
-        }
-    }
-
-    private fun translateSquared(variable: IdentifierReference, dt: DataType) {
-        val asmVar = asmgen.asmVariableName(variable)
-        when(dt) {
-            DataType.BYTE, DataType.UBYTE -> {
-                asmgen.out("  lda  $asmVar")
-                asmgen.signExtendAYlsb(dt)
-                asmgen.out("  jsr  math.square")
-            }
-            DataType.UWORD, DataType.WORD -> {
-                asmgen.out("  lda  $asmVar |  ldy  $asmVar+1 |  jsr  math.square")
-            }
-            else -> throw AssemblyError("require integer dt for square")
-        }
-        asmgen.out("  sta  P8ESTACK_LO,x |  tya |  sta  P8ESTACK_HI,x |  dex")
-    }
-
-    private fun translateExpression(expr: PrefixExpression) {
-        translateExpressionInternal(expr.expression)
-        val itype = expr.inferType(program)
-        val type = itype.getOrElse { throw AssemblyError("unknown dt") }
-        when(expr.operator) {
-            "+" -> {}
-            "-" -> {
-                when(type) {
-                    in ByteDatatypes -> asmgen.out("  jsr  prog8_lib.neg_b")
-                    in WordDatatypes -> asmgen.out("  jsr  prog8_lib.neg_w")
-                    DataType.FLOAT -> asmgen.out("  jsr  floats.neg_f")
-                    else -> throw AssemblyError("weird type")
-                }
-            }
-            "~" -> {
-                when(type) {
-                    in ByteDatatypes ->
-                        asmgen.out("""
-                            lda  P8ESTACK_LO+1,x
-                            eor  #255
-                            sta  P8ESTACK_LO+1,x
-                            """)
-                    in WordDatatypes -> asmgen.out("  jsr  prog8_lib.inv_word")
-                    else -> throw AssemblyError("weird type")
-                }
-            }
-            else -> throw AssemblyError("invalid prefix operator ${expr.operator}")
-        }
-    }
-
-    private fun translateExpression(arrayExpr: ArrayIndexedExpression) {
-        val elementIDt = arrayExpr.inferType(program)
-        if(!elementIDt.isKnown)
-            throw AssemblyError("unknown dt")
-        val elementDt = elementIDt.getOr(DataType.UNDEFINED)
-        val arrayVarName = asmgen.asmVariableName(arrayExpr.arrayvar)
-
-        val arrayVarDecl = arrayExpr.arrayvar.targetVarDecl(program)!!
-        if(arrayVarDecl.datatype==DataType.UWORD) {
-            // indexing a pointer var instead of a real array or string
-            if(elementDt !in ByteDatatypes)
-                throw AssemblyError("non-array var indexing requires bytes dt")
-            if(arrayExpr.inferType(program) isnot DataType.UBYTE)
-                throw AssemblyError("non-array var indexing requires bytes index")
-            asmgen.loadScaledArrayIndexIntoRegister(arrayExpr, elementDt, CpuRegister.Y)
-            if(asmgen.isZpVar(arrayExpr.arrayvar)) {
-                asmgen.out("  lda  ($arrayVarName),y")
-            } else {
-                asmgen.out("  lda  $arrayVarName |  sta  P8ZP_SCRATCH_W1 |  lda  $arrayVarName+1 |  sta  P8ZP_SCRATCH_W1+1")
-                asmgen.out("  lda  (P8ZP_SCRATCH_W1),y")
-            }
-            asmgen.out("  sta  P8ESTACK_LO,x |  dex")
-            return
-        }
-
-        val constIndexNum = arrayExpr.indexer.constIndex()
-        if(constIndexNum!=null) {
-            val indexValue = constIndexNum * program.memsizer.memorySize(elementDt)
-            when(elementDt) {
-                in ByteDatatypes -> {
-                    asmgen.out("  lda  $arrayVarName+$indexValue |  sta  P8ESTACK_LO,x |  dex")
-                }
-                in WordDatatypes -> {
-                    asmgen.out("  lda  $arrayVarName+$indexValue |  sta  P8ESTACK_LO,x |  lda  $arrayVarName+$indexValue+1 |  sta  P8ESTACK_HI,x |  dex")
-                }
-                DataType.FLOAT -> {
-                    asmgen.out("  lda  #<($arrayVarName+$indexValue) |  ldy  #>($arrayVarName+$indexValue) |  jsr  floats.push_float")
-                }
-                else -> throw AssemblyError("weird element type")
-            }
-        } else {
-            when(elementDt) {
-                in ByteDatatypes -> {
-                    asmgen.loadScaledArrayIndexIntoRegister(arrayExpr, elementDt, CpuRegister.Y)
-                    asmgen.out(" lda  $arrayVarName,y |  sta  P8ESTACK_LO,x |  dex")
-                }
-                in WordDatatypes -> {
-                    asmgen.loadScaledArrayIndexIntoRegister(arrayExpr, elementDt, CpuRegister.Y)
-                    asmgen.out(" lda  $arrayVarName,y |  sta  P8ESTACK_LO,x |  lda  $arrayVarName+1,y |  sta  P8ESTACK_HI,x |  dex")
-                }
-                DataType.FLOAT -> {
-                    asmgen.loadScaledArrayIndexIntoRegister(arrayExpr, elementDt, CpuRegister.A)
-                    asmgen.out("""
-                        ldy  #>$arrayVarName
-                        clc
-                        adc  #<$arrayVarName
-                        bcc  +
-                        iny
-+                       jsr  floats.push_float""")
-                }
-                else -> throw AssemblyError("weird dt")
-            }
-
-        }
-    }
-
-    private fun translateBinaryOperatorBytes(operator: String, types: DataType) {
-        when(operator) {
-            "*" -> asmgen.out("  jsr  prog8_lib.mul_byte")  //  the optimized routines should have been checked earlier
-            "/" -> asmgen.out(if(types==DataType.UBYTE) "  jsr  prog8_lib.idiv_ub" else "  jsr  prog8_lib.idiv_b")
-            "%" -> {
-                if(types==DataType.BYTE)
-                    throw AssemblyError("remainder of signed integers is not properly defined/implemented, use unsigned instead")
-                asmgen.out("  jsr prog8_lib.remainder_ub")
-            }
-            "+" -> asmgen.out("""
-                lda  P8ESTACK_LO+2,x
-                clc
-                adc  P8ESTACK_LO+1,x
-                inx
-                sta  P8ESTACK_LO+1,x
-                """)
-            "-" -> asmgen.out("""
-                lda  P8ESTACK_LO+2,x
-                sec
-                sbc  P8ESTACK_LO+1,x
-                inx
-                sta  P8ESTACK_LO+1,x
-                """)
-            "<<" -> asmgen.out("  jsr  prog8_lib.shiftleft_b")
-            ">>" -> asmgen.out("  jsr  prog8_lib.shiftright_b")
-            "<" -> asmgen.out(if(types==DataType.UBYTE) "  jsr  prog8_lib.less_ub" else "  jsr  prog8_lib.less_b")
-            ">" -> asmgen.out(if(types==DataType.UBYTE) "  jsr  prog8_lib.greater_ub" else "  jsr  prog8_lib.greater_b")
-            "<=" -> asmgen.out(if(types==DataType.UBYTE) "  jsr  prog8_lib.lesseq_ub" else "  jsr  prog8_lib.lesseq_b")
-            ">=" -> asmgen.out(if(types==DataType.UBYTE) "  jsr  prog8_lib.greatereq_ub" else "  jsr  prog8_lib.greatereq_b")
-            "==" -> asmgen.out("  jsr  prog8_lib.equal_b")
-            "!=" -> asmgen.out("  jsr  prog8_lib.notequal_b")
-            "&" -> asmgen.out("  jsr  prog8_lib.bitand_b")
-            "^" -> asmgen.out("  jsr  prog8_lib.bitxor_b")
-            "|" -> asmgen.out("  jsr  prog8_lib.bitor_b")
-            else -> throw AssemblyError("invalid operator $operator")
-        }
-    }
-
-    private fun translateBinaryOperatorWords(operator: String, dt: DataType) {
-        when(operator) {
-            "*" -> asmgen.out("  jsr  prog8_lib.mul_word")
-            "/" -> asmgen.out(if(dt==DataType.UWORD) "  jsr  prog8_lib.idiv_uw" else "  jsr  prog8_lib.idiv_w")
-            "%" -> {
-                if(dt==DataType.WORD)
-                    throw AssemblyError("remainder of signed integers is not properly defined/implemented, use unsigned instead")
-                asmgen.out("  jsr prog8_lib.remainder_uw")
-            }
-            "+" -> asmgen.out("  jsr  prog8_lib.add_w")
-            "-" -> asmgen.out("  jsr  prog8_lib.sub_w")
-            "<<" -> asmgen.out("  jsr  math.shift_left_w")
-            ">>" -> {
-                if(dt==DataType.UWORD)
-                    asmgen.out("  jsr  math.shift_right_uw")
-                else
-                    asmgen.out("  jsr  math.shift_right_w")
-            }
-            "<" -> asmgen.out(if(dt==DataType.UWORD) "  jsr  prog8_lib.less_uw" else "  jsr  prog8_lib.less_w")
-            ">" -> asmgen.out(if(dt==DataType.UWORD) "  jsr  prog8_lib.greater_uw" else "  jsr  prog8_lib.greater_w")
-            "<=" -> asmgen.out(if(dt==DataType.UWORD) "  jsr  prog8_lib.lesseq_uw" else "  jsr  prog8_lib.lesseq_w")
-            ">=" -> asmgen.out(if(dt==DataType.UWORD) "  jsr  prog8_lib.greatereq_uw" else "  jsr  prog8_lib.greatereq_w")
-            "==" -> asmgen.out("  jsr  prog8_lib.equal_w")
-            "!=" -> asmgen.out("  jsr  prog8_lib.notequal_w")
-            "&" -> asmgen.out("  jsr  prog8_lib.bitand_w")
-            "^" -> asmgen.out("  jsr  prog8_lib.bitxor_w")
-            "|" -> asmgen.out("  jsr  prog8_lib.bitor_w")
-            else -> throw AssemblyError("invalid operator $operator")
-        }
-    }
-
-    private fun translateBinaryOperatorFloats(operator: String) {
-        when(operator) {
-            "*" -> asmgen.out("  jsr  floats.mul_f")
-            "/" -> asmgen.out("  jsr  floats.div_f")
-            "+" -> asmgen.out("  jsr  floats.add_f")
-            "-" -> asmgen.out("  jsr  floats.sub_f")
-            "<" -> asmgen.out("  jsr  floats.less_f")
-            ">" -> asmgen.out("  jsr  floats.greater_f")
-            "<=" -> asmgen.out("  jsr  floats.lesseq_f")
-            ">=" -> asmgen.out("  jsr  floats.greatereq_f")
-            "==" -> asmgen.out("  jsr  floats.equal_f")
-            "!=" -> asmgen.out("  jsr  floats.notequal_f")
-            "%", "<<", ">>", "&", "^", "|" -> throw AssemblyError("requires integer datatype")
-            else -> throw AssemblyError("invalid operator $operator")
-        }
-    }
-
-    private fun translateCompareStrings(s1: Expression, operator: String, s2: Expression) {
-        asmgen.assignExpressionToVariable(s1, "prog8_lib.strcmp_expression._arg_s1", DataType.UWORD, null)
-        asmgen.assignExpressionToVariable(s2, "prog8_lib.strcmp_expression._arg_s2", DataType.UWORD, null)
-        asmgen.out(" jsr  prog8_lib.strcmp_expression")    // result  of compare is in A
-        when(operator) {
-            "==" -> asmgen.out(" and  #1 |  eor  #1 |  sta  P8ESTACK_LO,x")
-            "!=" -> asmgen.out(" and  #1 |  sta  P8ESTACK_LO,x")
-            "<=" -> asmgen.out("""
-                bpl  +
-                lda  #1
-                bne  ++
-+               lda  #0
-+               sta  P8ESTACK_LO,x""")
-            ">=" -> asmgen.out("""
-                bmi  +
-                lda  #1
-                bne  ++
-+               lda  #0
-+               sta  P8ESTACK_LO,x""")
-            "<" -> asmgen.out("""
-                bmi  +
-                lda  #0
-                beq  ++
-+               lda  #1
-+               sta  P8ESTACK_LO,x""")
-            ">" -> asmgen.out("""
-                bpl  +
-                lda  #0
-                beq  ++
-+               lda  #1
-+               sta  P8ESTACK_LO,x""")
-        }
-        asmgen.out("  dex")
-    }
-}

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

@@ -0,0 +1,40 @@
+package prog8.codegen.cpu6502
+
+import prog8.code.ast.IPtSubroutine
+import prog8.code.ast.PtAsmSub
+import prog8.code.ast.PtSub
+import prog8.code.core.*
+
+
+internal fun IPtSubroutine.returnsWhatWhere(): List<Pair<RegisterOrStatusflag, DataType>> {
+    when(this) {
+        is PtAsmSub -> {
+            return returns
+        }
+        is PtSub -> {
+            // for non-asm subroutines, determine the return registers based on the type of the return value
+            return if(returntype==null)
+                emptyList()
+            else {
+                val register = when (returntype!!) {
+                    in ByteDatatypes -> RegisterOrStatusflag(RegisterOrPair.A, null)
+                    in WordDatatypes -> RegisterOrStatusflag(RegisterOrPair.AY, null)
+                    DataType.FLOAT -> RegisterOrStatusflag(RegisterOrPair.FAC1, null)
+                    else -> RegisterOrStatusflag(RegisterOrPair.AY, null)
+                }
+                listOf(Pair(register, returntype!!))
+            }
+        }
+    }
+}
+
+
+internal fun PtSub.returnRegister(): RegisterOrStatusflag? {
+    return when(returntype) {
+        in ByteDatatypes -> RegisterOrStatusflag(RegisterOrPair.A, null)
+        in WordDatatypes -> RegisterOrStatusflag(RegisterOrPair.AY, null)
+        DataType.FLOAT -> RegisterOrStatusflag(RegisterOrPair.FAC1, null)
+        null -> null
+        else -> RegisterOrStatusflag(RegisterOrPair.AY, null)
+    }
+}

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

@@ -1,46 +1,48 @@
 package prog8.codegen.cpu6502
 
 import com.github.michaelbull.result.fold
-import prog8.ast.Program
+import prog8.code.StMemVar
-import prog8.ast.expressions.IdentifierReference
+import prog8.code.StStaticVariable
-import prog8.ast.expressions.RangeExpression
+import prog8.code.ast.PtForLoop
-import prog8.ast.statements.ForLoop
+import prog8.code.ast.PtIdentifier
+import prog8.code.ast.PtRange
 import prog8.code.core.*
 import kotlin.math.absoluteValue
 
-internal class ForLoopsAsmGen(private val program: Program, private val asmgen: AsmGen, private val zeropage: Zeropage) {
+internal class ForLoopsAsmGen(
+    private val asmgen: AsmGen6502Internal,
+    private val zeropage: Zeropage
+) {
 
-    internal fun translate(stmt: ForLoop) {
+    internal fun translate(stmt: PtForLoop) {
-        val iterableDt = stmt.iterable.inferType(program)
+        val iterableDt = stmt.iterable.type
-        if(!iterableDt.isKnown)
-            throw AssemblyError("unknown dt")
         when(stmt.iterable) {
-            is RangeExpression -> {
+            is PtRange -> {
-                val range = (stmt.iterable as RangeExpression).toConstantIntegerRange()
+                val range = (stmt.iterable as PtRange).toConstantIntegerRange()
                 if(range==null) {
-                    translateForOverNonconstRange(stmt, iterableDt.getOrElse { throw AssemblyError("unknown dt") }, stmt.iterable as RangeExpression)
+                    translateForOverNonconstRange(stmt, iterableDt, stmt.iterable as PtRange)
                 } else {
-                    translateForOverConstRange(stmt, iterableDt.getOrElse { throw AssemblyError("unknown dt") }, range)
+                    translateForOverConstRange(stmt, iterableDt, range)
                 }
             }
-            is IdentifierReference -> {
+            is PtIdentifier -> {
-                translateForOverIterableVar(stmt, iterableDt.getOrElse { throw AssemblyError("unknown dt") }, stmt.iterable as IdentifierReference)
+                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: ForLoop, iterableDt: DataType, range: RangeExpression) {
+    private fun translateForOverNonconstRange(stmt: PtForLoop, iterableDt: DataType, range: PtRange) {
-        val loopLabel = program.makeLabel("for_loop")
+        val loopLabel = asmgen.makeLabel("for_loop")
-        val endLabel = program.makeLabel("for_end")
+        val endLabel = asmgen.makeLabel("for_end")
-        val modifiedLabel = program.makeLabel("for_modified")
+        val modifiedLabel = asmgen.makeLabel("for_modified")
-        val modifiedLabel2 = program.makeLabel("for_modifiedb")
+        val modifiedLabel2 = asmgen.makeLabel("for_modifiedb")
         asmgen.loopEndLabels.push(endLabel)
-        val stepsize=range.step.constValue(program)!!.number.toInt()
+        val stepsize=range.step.asConstInteger()!!
 
         if(stepsize < -1) {
-            val limit = range.to.constValue(program)?.number
+            val limit = range.to.asConstInteger()
-            if(limit==0.0)
+            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")
         }
 
@@ -52,11 +54,39 @@ internal class ForLoopsAsmGen(private val program: Program, private val asmgen:
 
                     val incdec = if(stepsize==1) "inc" else "dec"
                     // loop over byte range via loopvar
-                    val varname = asmgen.asmVariableName(stmt.loopVar)
+                    val varname = asmgen.asmVariableName(stmt.variable)
-                    asmgen.assignExpressionToVariable(range.from, varname, ArrayToElementTypes.getValue(iterableDt), null)
+                    asmgen.assignExpressionToVariable(range.from, varname, ArrayToElementTypes.getValue(iterableDt))
-                    asmgen.assignExpressionToVariable(range.to, "$modifiedLabel+1", ArrayToElementTypes.getValue(iterableDt), null)
+                    asmgen.assignExpressionToRegister(range.to, RegisterOrPair.A, false)
+                    // pre-check for end already reached
+                    if(iterableDt==DataType.ARRAY_B) {
+                        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(stmt.body)
+                    asmgen.translate(stmt.statements)
                     asmgen.out("""
                         lda  $varname
 $modifiedLabel          cmp  #0         ; modified 
@@ -70,11 +100,39 @@ $modifiedLabel          cmp  #0         ; modified
                     // bytes, step >= 2 or <= -2
 
                     // loop over byte range via loopvar
-                    val varname = asmgen.asmVariableName(stmt.loopVar)
+                    val varname = asmgen.asmVariableName(stmt.variable)
-                    asmgen.assignExpressionToVariable(range.from, varname, ArrayToElementTypes.getValue(iterableDt), null)
+                    asmgen.assignExpressionToVariable(range.from, varname, ArrayToElementTypes.getValue(iterableDt))
-                    asmgen.assignExpressionToVariable(range.to, "$modifiedLabel+1", ArrayToElementTypes.getValue(iterableDt), null)
+                    asmgen.assignExpressionToRegister(range.to, RegisterOrPair.A, false)
+                    // pre-check for end already reached
+                    if(iterableDt==DataType.ARRAY_B) {
+                        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(stmt.body)
+                    asmgen.translate(stmt.statements)
                     if(stepsize>0) {
                         asmgen.out("""
                             lda  $varname
@@ -102,14 +160,15 @@ $modifiedLabel              cmp  #0     ; modified
                     // words, step 1 or -1
 
                     stepsize == 1 || stepsize == -1 -> {
-                        val varname = asmgen.asmVariableName(stmt.loopVar)
+                        val varname = asmgen.asmVariableName(stmt.variable)
-                        assignLoopvar(stmt, range)
+                        assignLoopvarWord(stmt, range)
                         asmgen.assignExpressionToRegister(range.to, RegisterOrPair.AY)
+                        precheckFromToWord(iterableDt, stepsize, varname, endLabel)
                         asmgen.out("""
                             sty  $modifiedLabel+1
                             sta  $modifiedLabel2+1
 $loopLabel""")
-                        asmgen.translate(stmt.body)
+                        asmgen.translate(stmt.statements)
                         asmgen.out("""
                 lda  $varname+1
 $modifiedLabel  cmp  #0    ; modified 
@@ -136,14 +195,15 @@ $modifiedLabel2 cmp  #0    ; modified
                     stepsize > 0 -> {
 
                         // (u)words, step >= 2
-                        val varname = asmgen.asmVariableName(stmt.loopVar)
+                        val varname = asmgen.asmVariableName(stmt.variable)
-                        assignLoopvar(stmt, range)
+                        assignLoopvarWord(stmt, range)
                         asmgen.assignExpressionToRegister(range.to, RegisterOrPair.AY)
+                        precheckFromToWord(iterableDt, stepsize, varname, endLabel)
                         asmgen.out("""
                             sty  $modifiedLabel+1
                             sta  $modifiedLabel2+1
 $loopLabel""")
-                        asmgen.translate(stmt.body)
+                        asmgen.translate(stmt.statements)
 
                         if (iterableDt == DataType.ARRAY_UW) {
                             asmgen.out("""
@@ -184,42 +244,26 @@ $endLabel""")
                     else -> {
 
                         // (u)words, step <= -2
-                        val varname = asmgen.asmVariableName(stmt.loopVar)
+                        val varname = asmgen.asmVariableName(stmt.variable)
-                        assignLoopvar(stmt, range)
+                        assignLoopvarWord(stmt, range)
                         asmgen.assignExpressionToRegister(range.to, RegisterOrPair.AY)
+                        precheckFromToWord(iterableDt, stepsize, varname, endLabel)
                         asmgen.out("""
                             sty  $modifiedLabel+1
                             sta  $modifiedLabel2+1
 $loopLabel""")
-                        asmgen.translate(stmt.body)
+                        asmgen.translate(stmt.statements)
 
-                        if(iterableDt==DataType.ARRAY_UW) {
                             asmgen.out("""
                 lda  $varname
                 sec
                 sbc  #<${stepsize.absoluteValue}
                 sta  $varname
+                tax
                 lda  $varname+1
                 sbc  #>${stepsize.absoluteValue}
                 sta  $varname+1
-$modifiedLabel  cmp  #0    ; modified                
+                txa
-                bcc  $endLabel
-                bne  $loopLabel
-                lda  $varname
-$modifiedLabel2 cmp  #0    ; modified 
-                bcs  $loopLabel
-$endLabel""")
-                        } else {
-                            asmgen.out("""
-                lda  $varname
-                sec
-                sbc  #<${stepsize.absoluteValue}
-                sta  $varname
-                pha
-                lda  $varname+1
-                sbc  #>${stepsize.absoluteValue}
-                sta  $varname+1
-                pla
 $modifiedLabel2 cmp  #0    ; modified 
                 lda  $varname+1
 $modifiedLabel  sbc  #0    ; modified
@@ -227,7 +271,6 @@ $modifiedLabel  sbc  #0    ; modified
                 eor  #$80
 +               bpl  $loopLabel                
 $endLabel""")
-                        }
                     }
                 }
             }
@@ -237,12 +280,67 @@ $endLabel""")
         asmgen.loopEndLabels.pop()
     }
 
-    private fun translateForOverIterableVar(stmt: ForLoop, iterableDt: DataType, ident: IdentifierReference) {
+    private fun precheckFromToWord(iterableDt: DataType, stepsize: Int, fromVar: String, endLabel: String) {
-        val loopLabel = program.makeLabel("for_loop")
+        // pre-check for end already reached.
-        val endLabel = program.makeLabel("for_end")
+        // 'to' is in AY, do NOT clobber this!
+        if(iterableDt==DataType.ARRAY_W) {
+            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.push(endLabel)
         val iterableName = asmgen.asmVariableName(ident)
-        val decl = ident.targetVarDecl(program)!!
+        val symbol = asmgen.symbolTable.lookup(ident.name)
+        val numElements = when(symbol) {
+            is StStaticVariable -> symbol.length!!
+            is StMemVar -> symbol.length!!
+            else -> 0
+        }
         when(iterableDt) {
             DataType.STR -> {
                 asmgen.out("""
@@ -252,8 +350,8 @@ $endLabel""")
                     sty  $loopLabel+2
 $loopLabel          lda  ${65535.toHex()}       ; modified
                     beq  $endLabel
-                    sta  ${asmgen.asmVariableName(stmt.loopVar)}""")
+                    sta  ${asmgen.asmVariableName(stmt.variable)}""")
-                asmgen.translate(stmt.body)
+                asmgen.translate(stmt.statements)
                 asmgen.out("""
                     inc  $loopLabel+1
                     bne  $loopLabel
@@ -262,19 +360,18 @@ $loopLabel          lda  ${65535.toHex()}       ; modified
 $endLabel""")
             }
             DataType.ARRAY_UB, DataType.ARRAY_B -> {
-                val length = decl.arraysize!!.constIndex()!!
+                val indexVar = asmgen.makeLabel("for_index")
-                val indexVar = program.makeLabel("for_index")
                 asmgen.out("""
                     ldy  #0
 $loopLabel          sty  $indexVar
                     lda  $iterableName,y
-                    sta  ${asmgen.asmVariableName(stmt.loopVar)}""")
+                    sta  ${asmgen.asmVariableName(stmt.variable)}""")
-                asmgen.translate(stmt.body)
+                asmgen.translate(stmt.statements)
-                if(length<=255) {
+                if(numElements<=255) {
                     asmgen.out("""
                         ldy  $indexVar
                         iny
-                        cpy  #$length
+                        cpy  #$numElements
                         beq  $endLabel
                         bne  $loopLabel""")
                 } else {
@@ -285,11 +382,11 @@ $loopLabel          sty  $indexVar
                         bne  $loopLabel
                         beq  $endLabel""")
                 }
-                if(length>=16) {
+                if(numElements>=16) {
                     // allocate index var on ZP if possible
-                    val result = zeropage.allocate(listOf(indexVar), DataType.UBYTE, null, stmt.position, asmgen.errors)
+                    val result = zeropage.allocate(indexVar, DataType.UBYTE, null, stmt.position, asmgen.errors)
                     result.fold(
-                        success = { (address,_)-> asmgen.out("""$indexVar = $address  ; auto zp UBYTE""") },
+                        success = { (address, _, _)-> asmgen.out("""$indexVar = $address  ; auto zp UBYTE""") },
                         failure = { asmgen.out("$indexVar    .byte  0") }
                     )
                 } else {
@@ -298,9 +395,9 @@ $loopLabel          sty  $indexVar
                 asmgen.out(endLabel)
             }
             DataType.ARRAY_W, DataType.ARRAY_UW -> {
-                val length = decl.arraysize!!.constIndex()!! * 2
+                val length = numElements * 2
-                val indexVar = program.makeLabel("for_index")
+                val indexVar = asmgen.makeLabel("for_index")
-                val loopvarName = asmgen.asmVariableName(stmt.loopVar)
+                val loopvarName = asmgen.asmVariableName(stmt.variable)
                 asmgen.out("""
                     ldy  #0
 $loopLabel          sty  $indexVar
@@ -308,7 +405,7 @@ $loopLabel          sty  $indexVar
                     sta  $loopvarName
                     lda  $iterableName+1,y
                     sta  $loopvarName+1""")
-                asmgen.translate(stmt.body)
+                asmgen.translate(stmt.statements)
                 if(length<=127) {
                     asmgen.out("""
                         ldy  $indexVar
@@ -328,9 +425,47 @@ $loopLabel          sty  $indexVar
                 }
                 if(length>=16) {
                     // allocate index var on ZP if possible
-                    val result = zeropage.allocate(listOf(indexVar), DataType.UBYTE, null, stmt.position, asmgen.errors)
+                    val result = zeropage.allocate(indexVar, DataType.UBYTE, null, stmt.position, asmgen.errors)
                     result.fold(
-                        success = { (address,_)-> asmgen.out("""$indexVar = $address  ; auto zp UBYTE""") },
+                        success = { (address,_,_)-> asmgen.out("""$indexVar = $address  ; auto zp UBYTE""") },
+                        failure = { asmgen.out("$indexVar    .byte  0") }
+                    )
+                } else {
+                    asmgen.out("$indexVar    .byte  0")
+                }
+                asmgen.out(endLabel)
+            }
+            DataType.ARRAY_UW_SPLIT, DataType.ARRAY_W_SPLIT -> {
+                val indexVar = asmgen.makeLabel("for_index")
+                val loopvarName = asmgen.asmVariableName(stmt.variable)
+                asmgen.out("""
+                    ldy  #0
+$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  $endLabel""")
+                }
+                if(numElements>=16) {
+                    // allocate index var on ZP if possible
+                    val result = zeropage.allocate(indexVar, DataType.UBYTE, null, stmt.position, asmgen.errors)
+                    result.fold(
+                        success = { (address,_,_)-> asmgen.out("""$indexVar = $address  ; auto zp UBYTE""") },
                         failure = { asmgen.out("$indexVar    .byte  0") }
                     )
                 } else {
@@ -346,7 +481,7 @@ $loopLabel          sty  $indexVar
         asmgen.loopEndLabels.pop()
     }
 
-    private fun translateForOverConstRange(stmt: ForLoop, iterableDt: DataType, range: IntProgression) {
+    private fun translateForOverConstRange(stmt: PtForLoop, iterableDt: DataType, range: IntProgression) {
         if (range.isEmpty() || range.step==0)
             throw AssemblyError("empty range or step 0")
         if(iterableDt==DataType.ARRAY_B || iterableDt==DataType.ARRAY_UB) {
@@ -359,18 +494,18 @@ $loopLabel          sty  $indexVar
         }
 
         // not one of the easy cases, generate more complex code...
-        val loopLabel = program.makeLabel("for_loop")
+        val loopLabel = asmgen.makeLabel("for_loop")
-        val endLabel = program.makeLabel("for_end")
+        val endLabel = asmgen.makeLabel("for_end")
         asmgen.loopEndLabels.push(endLabel)
         when(iterableDt) {
             DataType.ARRAY_B, DataType.ARRAY_UB -> {
                 // loop over byte range via loopvar, step >= 2 or <= -2
-                val varname = asmgen.asmVariableName(stmt.loopVar)
+                val varname = asmgen.asmVariableName(stmt.variable)
                 asmgen.out("""
                             lda  #${range.first}
                             sta  $varname
 $loopLabel""")
-                asmgen.translate(stmt.body)
+                asmgen.translate(stmt.statements)
                 when (range.step) {
                     0, 1, -1 -> {
                         throw AssemblyError("step 0, 1 and -1 should have been handled specifically  $stmt")
@@ -430,7 +565,7 @@ $loopLabel""")
             }
             DataType.ARRAY_W, DataType.ARRAY_UW -> {
                 // loop over word range via loopvar, step >= 2 or <= -2
-                val varname = asmgen.asmVariableName(stmt.loopVar)
+                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")
@@ -444,7 +579,7 @@ $loopLabel""")
                             sta  $varname
                             sty  $varname+1
 $loopLabel""")
-                        asmgen.translate(stmt.body)
+                        asmgen.translate(stmt.statements)
                         asmgen.out("""
                             lda  $varname
                             cmp  #<${range.last}
@@ -470,16 +605,16 @@ $loopLabel""")
         asmgen.loopEndLabels.pop()
     }
 
-    private fun translateForSimpleByteRangeAsc(stmt: ForLoop, range: IntProgression) {
+    private fun translateForSimpleByteRangeAsc(stmt: PtForLoop, range: IntProgression) {
-        val loopLabel = program.makeLabel("for_loop")
+        val loopLabel = asmgen.makeLabel("for_loop")
-        val endLabel = program.makeLabel("for_end")
+        val endLabel = asmgen.makeLabel("for_end")
         asmgen.loopEndLabels.push(endLabel)
-        val varname = asmgen.asmVariableName(stmt.loopVar)
+        val varname = asmgen.asmVariableName(stmt.variable)
         asmgen.out("""
                 lda  #${range.first}
                 sta  $varname
 $loopLabel""")
-        asmgen.translate(stmt.body)
+        asmgen.translate(stmt.statements)
         if (range.last == 255) {
             asmgen.out("""
                 inc  $varname
@@ -496,16 +631,16 @@ $endLabel""")
         asmgen.loopEndLabels.pop()
     }
 
-    private fun translateForSimpleByteRangeDesc(stmt: ForLoop, range: IntProgression) {
+    private fun translateForSimpleByteRangeDesc(stmt: PtForLoop, range: IntProgression) {
-        val loopLabel = program.makeLabel("for_loop")
+        val loopLabel = asmgen.makeLabel("for_loop")
-        val endLabel = program.makeLabel("for_end")
+        val endLabel = asmgen.makeLabel("for_end")
         asmgen.loopEndLabels.push(endLabel)
-        val varname = asmgen.asmVariableName(stmt.loopVar)
+        val varname = asmgen.asmVariableName(stmt.variable)
         asmgen.out("""
                     lda  #${range.first}
                     sta  $varname
 $loopLabel""")
-        asmgen.translate(stmt.body)
+        asmgen.translate(stmt.statements)
         when (range.last) {
             0 -> {
                 asmgen.out("""
@@ -533,18 +668,18 @@ $endLabel""")
         asmgen.loopEndLabels.pop()
     }
 
-    private fun translateForSimpleWordRangeAsc(stmt: ForLoop, range: IntProgression) {
+    private fun translateForSimpleWordRangeAsc(stmt: PtForLoop, range: IntProgression) {
-        val loopLabel = program.makeLabel("for_loop")
+        val loopLabel = asmgen.makeLabel("for_loop")
-        val endLabel = program.makeLabel("for_end")
+        val endLabel = asmgen.makeLabel("for_end")
         asmgen.loopEndLabels.push(endLabel)
-        val varname = asmgen.asmVariableName(stmt.loopVar)
+        val varname = asmgen.asmVariableName(stmt.variable)
         asmgen.out("""
             lda  #<${range.first}
             ldy  #>${range.first}
             sta  $varname
             sty  $varname+1
 $loopLabel""")
-        asmgen.translate(stmt.body)
+        asmgen.translate(stmt.statements)
         asmgen.out("""
             lda  $varname
             cmp  #<${range.last}
@@ -560,18 +695,18 @@ $loopLabel""")
         asmgen.loopEndLabels.pop()
     }
 
-    private fun translateForSimpleWordRangeDesc(stmt: ForLoop, range: IntProgression) {
+    private fun translateForSimpleWordRangeDesc(stmt: PtForLoop, range: IntProgression) {
-        val loopLabel = program.makeLabel("for_loop")
+        val loopLabel = asmgen.makeLabel("for_loop")
-        val endLabel = program.makeLabel("for_end")
+        val endLabel = asmgen.makeLabel("for_end")
         asmgen.loopEndLabels.push(endLabel)
-        val varname = asmgen.asmVariableName(stmt.loopVar)
+        val varname = asmgen.asmVariableName(stmt.variable)
         asmgen.out("""
             lda  #<${range.first}
             ldy  #>${range.first}
             sta  $varname
             sty  $varname+1
 $loopLabel""")
-        asmgen.translate(stmt.body)
+        asmgen.translate(stmt.statements)
         asmgen.out("""
             lda  $varname
             cmp  #<${range.last}
@@ -588,10 +723,9 @@ $loopLabel""")
         asmgen.loopEndLabels.pop()
     }
 
-    private fun assignLoopvar(stmt: ForLoop, range: RangeExpression) =
+    private fun assignLoopvarWord(stmt: PtForLoop, range: PtRange) =
         asmgen.assignExpressionToVariable(
             range.from,
-            asmgen.asmVariableName(stmt.loopVar),
+            asmgen.asmVariableName(stmt.variable),
-            stmt.loopVarDt(program).getOrElse { throw AssemblyError("unknown dt") },
+            stmt.variable.type)
-            stmt.definingSubroutine)
 }

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

@@ -1,16 +1,6 @@
 package prog8.codegen.cpu6502
 
-import prog8.ast.IFunctionCall
+import prog8.code.ast.*
-import prog8.ast.Node
-import prog8.ast.Program
-import prog8.ast.expressions.AddressOf
-import prog8.ast.expressions.Expression
-import prog8.ast.expressions.IdentifierReference
-import prog8.ast.expressions.NumericLiteral
-import prog8.ast.statements.FunctionCallStatement
-import prog8.ast.statements.InlineAssembly
-import prog8.ast.statements.Subroutine
-import prog8.ast.statements.SubroutineParameter
 import prog8.code.core.*
 import prog8.codegen.cpu6502.assignment.AsmAssignSource
 import prog8.codegen.cpu6502.assignment.AsmAssignTarget
@@ -18,68 +8,42 @@ import prog8.codegen.cpu6502.assignment.AsmAssignment
 import prog8.codegen.cpu6502.assignment.TargetStorageKind
 
 
-internal class FunctionCallAsmGen(private val program: Program, private val asmgen: AsmGen) {
+internal class FunctionCallAsmGen(private val program: PtProgram, private val asmgen: AsmGen6502Internal) {
 
-    internal fun translateFunctionCallStatement(stmt: FunctionCallStatement) {
+    internal fun translateFunctionCallStatement(stmt: PtFunctionCall) {
-        saveXbeforeCall(stmt)
+        translateFunctionCall(stmt)
-        translateFunctionCall(stmt, false)
-        restoreXafterCall(stmt)
         // just ignore any result values from the function call.
     }
 
-    internal fun saveXbeforeCall(stmt: IFunctionCall) {
+    internal fun optimizeIntArgsViaRegisters(sub: PtSub) =
-        val sub = stmt.target.targetSubroutine(program) ?: throw AssemblyError("undefined subroutine ${stmt.target}")
-        if(sub.shouldSaveX()) {
-            val regSaveOnStack = sub.asmAddress==null       // rom-routines don't require registers to be saved on stack, normal subroutines do because they can contain nested calls
-            if(regSaveOnStack)
-                asmgen.saveRegisterStack(CpuRegister.X, sub.shouldKeepA().saveOnEntry)
-            else
-                asmgen.saveRegisterLocal(CpuRegister.X, (stmt as Node).definingSubroutine!!)
-        }
-    }
-
-    internal fun restoreXafterCall(stmt: IFunctionCall) {
-        val sub = stmt.target.targetSubroutine(program) ?: throw AssemblyError("undefined subroutine ${stmt.target}")
-        if(sub.shouldSaveX()) {
-            val regSaveOnStack = sub.asmAddress==null       // rom-routines don't require registers to be saved on stack, normal subroutines do because they can contain nested calls
-            if(regSaveOnStack)
-                asmgen.restoreRegisterStack(CpuRegister.X, sub.shouldKeepA().saveOnReturn)
-            else
-                asmgen.restoreRegisterLocal(CpuRegister.X)
-        }
-    }
-
-    internal fun optimizeIntArgsViaRegisters(sub: Subroutine) =
         (sub.parameters.size==1 && sub.parameters[0].type in IntegerDatatypes)
                 || (sub.parameters.size==2 && sub.parameters[0].type in ByteDatatypes && sub.parameters[1].type in ByteDatatypes)
 
-    internal fun translateFunctionCall(call: IFunctionCall, isExpression: Boolean) {            // TODO remove isExpression unused parameter
+    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 sub = call.target.targetSubroutine(program) ?: throw AssemblyError("undefined subroutine ${call.target}")
+        val symbol = asmgen.symbolTable.lookup(call.name)
-        val subAsmName = asmgen.asmSymbolName(call.target)
+        val sub = symbol?.astNode as IPtSubroutine
+        val subAsmName = asmgen.asmSymbolName(call.name)
 
-        if(sub.isAsmSubroutine) {
+        if(sub is PtAsmSub) {
             argumentsViaRegisters(sub, call)
-            if (sub.inline && asmgen.options.optimize) {
+            if (sub.inline) {
-                // inline the subroutine.
+                // 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.statements.forEach { asmgen.translate(it as InlineAssembly) }
+                sub.children.forEach { asmgen.translate(it as PtInlineAssembly) }
                 asmgen.out("  \t; inlined routine end: ${sub.name}")
             } else {
                 asmgen.out("  jsr  $subAsmName")
             }
         }
-        else {
+        else if(sub is PtSub) {
-            if(sub.inline)
-                throw AssemblyError("can only reliably inline asmsub routines at this time")
-
             if(optimizeIntArgsViaRegisters(sub)) {
                 if(sub.parameters.size==1) {
                     val register = if (sub.parameters[0].type in ByteDatatypes) RegisterOrPair.A else RegisterOrPair.AY
@@ -100,85 +64,106 @@ internal class FunctionCallAsmGen(private val program: Program, private val asmg
             }
             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 argumentsViaRegisters(sub: Subroutine, call: IFunctionCall) {
+
+    private fun usesOtherRegistersWhileEvaluating(arg: PtExpression): Boolean {
+        return when(arg) {
+            is PtBuiltinFunctionCall -> {
+                if (arg.name == "lsb" || arg.name == "msb")
+                    return usesOtherRegistersWhileEvaluating(arg.args[0])
+                if (arg.name == "mkword")
+                    return usesOtherRegistersWhileEvaluating(arg.args[0]) || usesOtherRegistersWhileEvaluating(arg.args[1])
+                return !arg.isSimple()
+            }
+            is PtAddressOf -> false
+            is PtIdentifier -> false
+            is PtMachineRegister -> false
+            is PtMemoryByte -> false
+            is PtNumber -> false
+            else -> true
+        }
+    }
+
+    private fun 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()), call.args[0])
+            argumentViaRegister(sub, IndexedValue(0, sub.parameters.single().second), call.args[0])
         } else {
-            if(asmsub6502ArgsHaveRegisterClobberRisk(call.args, sub.asmParameterRegisters)) {
+            val optimalEvalOrder = asmsub6502ArgsEvalOrder(sub)
-                registerArgsViaCpuStackEvaluation(call, sub)
+            optimalEvalOrder.forEach {
-            } else {
+                val param = sub.parameters[it]
-                asmsub6502ArgsEvalOrder(sub).forEach {
+                val arg = call.args[it]
-                    val param = sub.parameters[it]
+                registersUsed += if(usesOtherRegistersWhileEvaluating(arg)) {
-                    val arg = call.args[it]
+                    if(!registersUsed.any{it.statusflag!=null || it.registerOrPair in CpuRegisters})
-                    argumentViaRegister(sub, IndexedValue(it, param), arg)
+                        argumentViaRegister(sub, IndexedValue(it, param.second), arg)
+                    else if(registersUsed.any {it.statusflag!=null}) {
+                        throw AssemblyError("call argument evaluation problem: can't save cpu statusregister parameter ${call.position}")
+                    }
+                    else {
+                        if(usedX()) asmgen.saveRegisterStack(CpuRegister.X, false)
+                        if(usedY()) asmgen.saveRegisterStack(CpuRegister.Y, false)
+                        if(usedA()) asmgen.saveRegisterStack(CpuRegister.A, false)
+                        val used = argumentViaRegister(sub, IndexedValue(it, param.second), arg)
+                        if(usedA()) asmgen.restoreRegisterStack(CpuRegister.A, false)
+                        if(usedY()) asmgen.restoreRegisterStack(CpuRegister.Y, true)
+                        if(usedX()) asmgen.restoreRegisterStack(CpuRegister.X, true)
+                        used
+                    }
+                } else {
+                    argumentViaRegister(sub, IndexedValue(it, param.second), arg)
                 }
             }
         }
     }
 
-    private fun registerArgsViaCpuStackEvaluation(call: IFunctionCall, callee: Subroutine) {
+    private fun argumentViaVariable(sub: PtSub, parameter: PtSubroutineParameter, value: PtExpression) {
-        // this is called when one or more of the arguments are 'complex' and
-        // cannot be assigned to a register easily or risk clobbering other registers.
-
-        require(callee.isAsmSubroutine) { "register args only for asm subroutine ${callee.position}" }
-        if(callee.parameters.isEmpty())
-            return
-
-        // use the cpu hardware stack as intermediate storage for the arguments.
-        val argOrder = asmsub6502ArgsEvalOrder(callee)
-        argOrder.reversed().forEach {
-            asmgen.pushCpuStack(callee.parameters[it].type, call.args[it])
-        }
-        argOrder.forEach {
-            val param = callee.parameters[it]
-            val targetVar = callee.searchParameter(param.name)!!
-            asmgen.popCpuStack(param.type, targetVar, (call as Node).definingSubroutine)
-        }
-    }
-
-    private fun argumentViaVariable(sub: Subroutine, parameter: SubroutineParameter, value: Expression) {
         // pass parameter via a regular variable (not via registers)
-        val valueIDt = value.inferType(program)
+        if(!isArgumentTypeCompatible(value.type, parameter.type))
-        val valueDt = valueIDt.getOrElse { throw AssemblyError("unknown dt") }
-        if(!isArgumentTypeCompatible(valueDt, parameter.type))
             throw AssemblyError("argument type incompatible")
 
-        val varName = asmgen.asmVariableName(sub.scopedName + parameter.name)
+        val varName = asmgen.asmVariableName(sub.scopedName + "." + parameter.name)
-        asmgen.assignExpressionToVariable(value, varName, parameter.type, sub)
+        asmgen.assignExpressionToVariable(value, varName, parameter.type)
     }
 
-    private fun argumentViaRegister(sub: Subroutine, parameter: IndexedValue<SubroutineParameter>, value: Expression, registerOverride: RegisterOrPair? = null) {
+    private fun argumentViaRegister(sub: IPtSubroutine, parameter: IndexedValue<PtSubroutineParameter>, value: PtExpression, registerOverride: RegisterOrPair? = null): RegisterOrStatusflag {
         // pass argument via a register parameter
-        val valueIDt = value.inferType(program)
+        if(!isArgumentTypeCompatible(value.type, parameter.value.type))
-        val valueDt = valueIDt.getOrElse { throw AssemblyError("unknown dt") }
-        if(!isArgumentTypeCompatible(valueDt, parameter.value.type))
             throw AssemblyError("argument type incompatible")
 
-        val paramRegister = if(registerOverride==null) sub.asmParameterRegisters[parameter.index] else RegisterOrStatusflag(registerOverride, null)
+        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!=valueDt) {
+        if(requiredDt!=value.type) {
-            if(valueDt largerThan requiredDt)
+            if(value.type largerThan requiredDt)
                 throw AssemblyError("can only convert byte values to word param types")
         }
         if (statusflag!=null) {
-            if(requiredDt!=valueDt)
+            if(requiredDt!=value.type)
                 throw AssemblyError("for statusflag, byte value is required")
             if (statusflag == Statusflag.Pc) {
-                // this param needs to be set last, right before the jsr
+                // 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 NumericLiteral -> {
+                    is PtNumber -> {
                         val carrySet = value.number.toInt() != 0
                         asmgen.out(if(carrySet) "  sec" else "  clc")
                     }
-                    is IdentifierReference -> {
+                    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
@@ -189,35 +174,34 @@ internal class FunctionCallAsmGen(private val program: Program, private val asmg
                     }
                     else -> {
                         asmgen.assignExpressionToRegister(value, RegisterOrPair.A)
-                        asmgen.out("""
+                        asmgen.out("  ror  a")
-                            beq  +
-                            sec
-                            bcs  ++
-+                           clc
-+""")
                     }
                 }
             } else throw AssemblyError("can only use Carry as status flag parameter")
+            return RegisterOrStatusflag(null, statusflag)
         }
         else {
             // via register or register pair
             register!!
-            if(requiredDt largerThan valueDt) {
+            if(requiredDt largerThan value.type) {
                 // we need to sign extend the source, do this via temporary word variable
-                asmgen.assignExpressionToVariable(value, "P8ZP_SCRATCH_W1", DataType.UBYTE, sub)
+                asmgen.assignExpressionToVariable(value, "P8ZP_SCRATCH_W1", DataType.UBYTE)
-                asmgen.signExtendVariableLsb("P8ZP_SCRATCH_W1", valueDt)
+                asmgen.signExtendVariableLsb("P8ZP_SCRATCH_W1", value.type)
-                asmgen.assignVariableToRegister("P8ZP_SCRATCH_W1", register)
+                asmgen.assignVariableToRegister("P8ZP_SCRATCH_W1", register, null, Position.DUMMY)
             } else {
+                val scope = value.definingISub()
                 val target: AsmAssignTarget =
                     if(parameter.value.type in ByteDatatypes && (register==RegisterOrPair.AX || register == RegisterOrPair.AY || register==RegisterOrPair.XY || register in Cx16VirtualRegisters))
-                        AsmAssignTarget(TargetStorageKind.REGISTER, asmgen, parameter.value.type, sub, register = register)
+                        AsmAssignTarget(TargetStorageKind.REGISTER, asmgen, parameter.value.type, scope, value.position, register = register)
                     else {
                         val signed = parameter.value.type == DataType.BYTE || parameter.value.type == DataType.WORD
-                        AsmAssignTarget.fromRegisters(register, signed, sub, asmgen)
+                        AsmAssignTarget.fromRegisters(register, signed, value.position, scope, asmgen)
                     }
-                val src = if(valueDt in PassByReferenceDatatypes) {
+                val src = if(value.type in PassByReferenceDatatypes) {
-                    if(value is IdentifierReference) {
+                    if(value is PtIdentifier) {
-                        val addr = AddressOf(value, Position.DUMMY)
+                        val addr = PtAddressOf(Position.DUMMY)
+                        addr.add(value)
+                        addr.parent = sub as PtNode
                         AsmAssignSource.fromAstSource(addr, program, asmgen).adjustSignedUnsigned(target)
                     } else {
                         AsmAssignSource.fromAstSource(value, program, asmgen).adjustSignedUnsigned(target)
@@ -225,8 +209,9 @@ internal class FunctionCallAsmGen(private val program: Program, private val asmg
                 } else {
                     AsmAssignSource.fromAstSource(value, program, asmgen).adjustSignedUnsigned(target)
                 }
-                asmgen.translateNormalAssignment(AsmAssignment(src, target, false, program.memsizer, Position.DUMMY))
+                asmgen.translateNormalAssignment(AsmAssignment(src, target, program.memsizer, Position.DUMMY), scope)
             }
+            return RegisterOrStatusflag(register, null)
         }
     }
 
@@ -248,3 +233,5 @@ internal class FunctionCallAsmGen(private val program: Program, private val asmg
         return false
     }
 }
+
+

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

@@ -1,23 +1,22 @@
 package prog8.codegen.cpu6502
 
-import prog8.ast.Program
+import prog8.code.ast.PtIdentifier
-import prog8.ast.expressions.IdentifierReference
+import prog8.code.ast.PtNumber
-import prog8.ast.expressions.NumericLiteral
+import prog8.code.ast.PtPostIncrDecr
-import prog8.ast.statements.PostIncrDecr
+import prog8.code.ast.PtProgram
 import prog8.code.core.*
 
 
-internal class PostIncrDecrAsmGen(private val program: Program, private val asmgen: AsmGen) {
+internal class PostIncrDecrAsmGen(private val program: PtProgram, private val asmgen: AsmGen6502Internal) {
-    internal fun translate(stmt: PostIncrDecr) {
+    internal fun translate(stmt: PtPostIncrDecr) {
         val incr = stmt.operator=="++"
         val targetIdent = stmt.target.identifier
-        val targetMemory = stmt.target.memoryAddress
+        val targetMemory = stmt.target.memory
-        val targetArrayIdx = stmt.target.arrayindexed
+        val targetArrayIdx = stmt.target.array
-        val scope = stmt.definingSubroutine
         when {
             targetIdent!=null -> {
                 val what = asmgen.asmVariableName(targetIdent)
-                when (stmt.target.inferType(program).getOr(DataType.UNDEFINED)) {
+                when (stmt.target.type) {
                     in ByteDatatypes -> asmgen.out(if (incr) "  inc  $what" else "  dec  $what")
                     in WordDatatypes -> {
                         if(incr)
@@ -38,12 +37,12 @@ internal class PostIncrDecrAsmGen(private val program: Program, private val asmg
                 }
             }
             targetMemory!=null -> {
-                when (val addressExpr = targetMemory.addressExpression) {
+                when (val addressExpr = targetMemory.address) {
-                    is NumericLiteral -> {
+                    is PtNumber -> {
                         val what = addressExpr.number.toHex()
                         asmgen.out(if(incr) "  inc  $what" else "  dec  $what")
                     }
-                    is IdentifierReference -> {
+                    is PtIdentifier -> {
                         val what = asmgen.asmVariableName(addressExpr)
                         asmgen.out("  lda  $what |  sta  (+) +1 |  lda  $what+1 |  sta  (+) +2")
                         if(incr)
@@ -62,23 +61,62 @@ internal class PostIncrDecrAsmGen(private val program: Program, private val asmg
                 }
             }
             targetArrayIdx!=null -> {
-                val asmArrayvarname = asmgen.asmVariableName(targetArrayIdx.arrayvar)
+                val asmArrayvarname = asmgen.asmVariableName(targetArrayIdx.variable)
-                val elementDt = targetArrayIdx.inferType(program).getOr(DataType.UNDEFINED)
+                val elementDt = targetArrayIdx.type
-                val constIndex = targetArrayIdx.indexer.constIndex()
+                val constIndex = targetArrayIdx.index.asConstInteger()
+                if(targetArrayIdx.splitWords) {
+                    if(constIndex!=null) {
+                        if(incr)
+                            asmgen.out(" inc  ${asmArrayvarname}_lsb+$constIndex |  bne  + |  inc  ${asmArrayvarname}_msb+$constIndex |+")
+                        else
+                            asmgen.out("""
+        lda  ${asmArrayvarname}_lsb+$constIndex
+        bne  +
+        dec  ${asmArrayvarname}_msb+$constIndex
++       dec  ${asmArrayvarname}_lsb+$constIndex""")
+                    } else {
+                        asmgen.loadScaledArrayIndexIntoRegister(targetArrayIdx, CpuRegister.X)
+                        if(incr)
+                            asmgen.out(" inc  ${asmArrayvarname}_lsb,x |  bne  + |  inc  ${asmArrayvarname}_msb,x |+")
+                        else
+                            asmgen.out("""
+        lda  ${asmArrayvarname}_lsb,x
+        bne  +
+        dec  ${asmArrayvarname}_msb,x
++       dec  ${asmArrayvarname}_lsb,x""")
+                    }
+                    return
+                }
                 if(constIndex!=null) {
                     val indexValue = constIndex * program.memsizer.memorySize(elementDt)
                     when(elementDt) {
-                        in ByteDatatypes -> asmgen.out(if (incr) "  inc  $asmArrayvarname+$indexValue" else "  dec  $asmArrayvarname+$indexValue")
+                        in ByteDatatypes -> {
+                            if(targetArrayIdx.usesPointerVariable) {
+                                asmgen.out("""
+                                    lda  $asmArrayvarname
+                                    clc
+                                    adc  #$indexValue
+                                    sta  (+) +1
+                                    lda  $asmArrayvarname+1
+                                    adc  #0
+                                    sta  (+) +2""")
+                                if(incr)
+                                    asmgen.out("+\tinc  ${'$'}ffff\t; modified")
+                                else
+                                    asmgen.out("+\tdec  ${'$'}ffff\t; modified")
+                            } else {
+                                asmgen.out(if (incr) "  inc  $asmArrayvarname+$indexValue" else "  dec  $asmArrayvarname+$indexValue")
+                            }
+                        }
                         in WordDatatypes -> {
                             if(incr)
                                 asmgen.out(" inc  $asmArrayvarname+$indexValue |  bne  + |  inc  $asmArrayvarname+$indexValue+1 |+")
                             else
                                 asmgen.out("""
-    lda  $asmArrayvarname+$indexValue
+        lda  $asmArrayvarname+$indexValue
-    bne  +
+        bne  +
-    dec  $asmArrayvarname+$indexValue+1
+        dec  $asmArrayvarname+$indexValue+1
-+       dec  $asmArrayvarname+$indexValue 
++       dec  $asmArrayvarname+$indexValue""")
-""")
                         }
                         DataType.FLOAT -> {
                             asmgen.out("  lda  #<($asmArrayvarname+$indexValue) |  ldy  #>($asmArrayvarname+$indexValue)")
@@ -89,36 +127,47 @@ internal class PostIncrDecrAsmGen(private val program: Program, private val asmg
                 }
                 else
                 {
-                    asmgen.loadScaledArrayIndexIntoRegister(targetArrayIdx, elementDt, CpuRegister.A)
+                    asmgen.loadScaledArrayIndexIntoRegister(targetArrayIdx, CpuRegister.X)
-                    asmgen.saveRegisterLocal(CpuRegister.X, scope!!)
-                    asmgen.out("  tax")
                     when(elementDt) {
                         in ByteDatatypes -> {
-                            asmgen.out(if(incr) "  inc  $asmArrayvarname,x" else "  dec  $asmArrayvarname,x")
+                            if(targetArrayIdx.usesPointerVariable) {
+                                asmgen.out("""
+                                    txa
+                                    clc
+                                    adc  $asmArrayvarname
+                                    sta  (+) +1
+                                    lda  $asmArrayvarname+1
+                                    adc  #0
+                                    sta  (+) +2""")
+                                if(incr)
+                                    asmgen.out("+\tinc  ${'$'}ffff\t; modified")
+                                else
+                                    asmgen.out("+\tdec  ${'$'}ffff\t; modified")
+                            } else {
+                                asmgen.out(if (incr) "  inc  $asmArrayvarname,x" else "  dec  $asmArrayvarname,x")
+                            }
                         }
                         in WordDatatypes -> {
                             if(incr)
                                 asmgen.out(" inc  $asmArrayvarname,x |  bne  + |  inc  $asmArrayvarname+1,x |+")
                             else
                                 asmgen.out("""
-    lda  $asmArrayvarname,x
+        lda  $asmArrayvarname,x
-    bne  +
+        bne  +
-    dec  $asmArrayvarname+1,x
+        dec  $asmArrayvarname+1,x
-+       dec  $asmArrayvarname,x 
++       dec  $asmArrayvarname,x""")
-""")
                         }
                         DataType.FLOAT -> {
                             asmgen.out("""
-                    ldy  #>$asmArrayvarname
+        ldy  #>$asmArrayvarname
-                    clc
+        clc
-                    adc  #<$asmArrayvarname
+        adc  #<$asmArrayvarname
-                    bcc  +
+        bcc  +
-                    iny
+        iny
-+                       jsr  floats.inc_var_f""")
++       jsr  floats.inc_var_f""")
                         }
                         else -> throw AssemblyError("weird array elt dt")
                     }
-                    asmgen.restoreRegisterLocal(CpuRegister.X)
                 }
             }
         }

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

@@ -1,12 +1,10 @@
 package prog8.codegen.cpu6502
 
-import prog8.ast.Program
-import prog8.ast.statements.*
 import prog8.code.*
+import prog8.code.ast.*
 import prog8.code.core.*
 import prog8.codegen.cpu6502.assignment.AsmAssignTarget
 import prog8.codegen.cpu6502.assignment.TargetStorageKind
-import prog8.compiler.CallGraph
 import java.time.LocalDate
 import java.time.LocalDateTime
 import kotlin.math.absoluteValue
@@ -20,30 +18,27 @@ import kotlin.math.absoluteValue
  *  - all variables (note: VarDecl ast nodes are *NOT* used anymore for this! now uses IVariablesAndConsts data tables!)
  */
 internal class ProgramAndVarsGen(
-    val program: Program,
+    val program: PtProgram,
     val options: CompilationOptions,
     val errors: IErrorReporter,
     private val symboltable: SymbolTable,
     private val functioncallAsmGen: FunctionCallAsmGen,
-    private val asmgen: AsmGen,
+    private val asmgen: AsmGen6502Internal,
     private val allocator: VariableAllocator,
     private val zeropage: Zeropage
 ) {
     private val compTarget = options.compTarget
-    private val callGraph = CallGraph(program, true)
+    private val blockVariableInitializers = program.allBlocks().associateWith { it.children.filterIsInstance<PtAssignment>() }
-    private val blockVariableInitializers = program.allBlocks.associateWith { it.statements.filterIsInstance<Assignment>() }
 
     internal fun generate() {
-        val allInitializers = blockVariableInitializers.asSequence().flatMap { it.value }
-        require(allInitializers.all { it.origin==AssignmentOrigin.VARINIT }) {"all block-level assignments must be a variable initializer"}
-
         header()
-        val allBlocks = program.allBlocks
+        val allBlocks = program.allBlocks()
-        if(allBlocks.first().name != "main")
+
-            throw AssemblyError("first block should be 'main'")
+        if(allBlocks.first().name != "p8b_main" && allBlocks.first().name != "main")
+            throw AssemblyError("first block should be 'main' or 'p8b_main'")
 
         if(errors.noErrors())  {
-            program.allBlocks.forEach { block2asm(it) }
+            program.allBlocks().forEach { block2asm(it) }
 
             // the global list of all floating point constants for the whole program
             asmgen.out("; global float constants")
@@ -71,7 +66,7 @@ internal class ProgramAndVarsGen(
         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'\n")
+        asmgen.out(".cpu  '$cpu'\n.enc  'none'")
 
         // the global prog8 variables needed
         val zp = zeropage
@@ -80,8 +75,6 @@ internal class ProgramAndVarsGen(
         asmgen.out("P8ZP_SCRATCH_W1 = ${zp.SCRATCH_W1}    ; word")
         asmgen.out("P8ZP_SCRATCH_W2 = ${zp.SCRATCH_W2}    ; word")
         asmgen.out(".weak")   // hack to allow user to override the following two with command line redefinition (however, just use '-esa' command line option instead!)
-        asmgen.out("P8ESTACK_LO = ${compTarget.machine.ESTACK_LO.toHex()}")
-        asmgen.out("P8ESTACK_HI = ${compTarget.machine.ESTACK_HI.toHex()}")
         asmgen.out(".endweak")
 
         if(options.symbolDefs.isNotEmpty()) {
@@ -94,13 +87,13 @@ internal class ProgramAndVarsGen(
         when(options.output) {
             OutputType.RAW -> {
                 asmgen.out("; ---- raw assembler program ----")
-                asmgen.out("* = ${options.loadAddress.toHex()}\n")
+                asmgen.out("* = ${options.loadAddress.toHex()}")
             }
             OutputType.PRG -> {
                 when(options.launcher) {
                     CbmPrgLauncherType.BASIC -> {
                         if (options.loadAddress != options.compTarget.machine.PROGRAM_LOAD_ADDRESS) {
-                            errors.err("BASIC output must have load address ${options.compTarget.machine.PROGRAM_LOAD_ADDRESS.toHex()}", program.toplevelModule.position)
+                            errors.err("BASIC output must have load address ${options.compTarget.machine.PROGRAM_LOAD_ADDRESS.toHex()}", program.position)
                         }
                         asmgen.out("; ---- basic program with sys call ----")
                         asmgen.out("* = ${options.loadAddress.toHex()}")
@@ -108,26 +101,26 @@ internal class ProgramAndVarsGen(
                         asmgen.out("  .word  (+), $year")
                         asmgen.out("  .null  $9e, format(' %d ', prog8_entrypoint), $3a, $8f, ' prog8'")
                         asmgen.out("+\t.word  0")
-                        asmgen.out("prog8_entrypoint\t; assembly code starts here\n")
+                        asmgen.out("prog8_entrypoint\t; assembly code starts here")
                         if(!options.noSysInit)
-                            asmgen.out("  jsr  ${compTarget.name}.init_system")
+                            asmgen.out("  jsr  sys.init_system")
-                        asmgen.out("  jsr  ${compTarget.name}.init_system_phase2")
+                        asmgen.out("  jsr  sys.init_system_phase2")
                     }
                     CbmPrgLauncherType.NONE -> {
                         asmgen.out("; ---- program without basic sys call ----")
-                        asmgen.out("* = ${options.loadAddress.toHex()}\n")
+                        asmgen.out("* = ${options.loadAddress.toHex()}")
                         if(!options.noSysInit)
-                            asmgen.out("  jsr  ${compTarget.name}.init_system")
+                            asmgen.out("  jsr  sys.init_system")
-                        asmgen.out("  jsr  ${compTarget.name}.init_system_phase2")
+                        asmgen.out("  jsr  sys.init_system_phase2")
                     }
                 }
             }
             OutputType.XEX -> {
                 asmgen.out("; ---- atari xex program ----")
-                asmgen.out("* = ${options.loadAddress.toHex()}\n")
+                asmgen.out("* = ${options.loadAddress.toHex()}")
                 if(!options.noSysInit)
-                    asmgen.out("  jsr  ${compTarget.name}.init_system")
+                    asmgen.out("  jsr  sys.init_system")
-                asmgen.out("  jsr  ${compTarget.name}.init_system_phase2")
+                asmgen.out("  jsr  sys.init_system_phase2")
             }
         }
 
@@ -140,90 +133,161 @@ internal class ProgramAndVarsGen(
                 pha""")
         }
 
-        // make sure that on the cx16 and c64, basic rom is banked in again when we exit the program
         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  main.start")
+                asmgen.out("  jsr  p8b_main.p8s_start")
-                asmgen.out("  jmp  ${compTarget.name}.cleanup_at_exit")
+                asmgen.out("  jmp  sys.cleanup_at_exit")
             }
             "c64" -> {
-                asmgen.out("  jsr  main.start |  lda  #31 |  sta  $01")
+                asmgen.out("  jsr  p8b_main.p8s_start |  lda  #31 |  sta  $01")
-                if(!options.noSysInit)
+                asmgen.out("  jmp  sys.cleanup_at_exit")
-                    asmgen.out("  jmp  ${compTarget.name}.cleanup_at_exit")
-                else
-                    asmgen.out("  rts")
             }
             "c128" -> {
-                asmgen.out("  jsr  main.start")
+                asmgen.out("  jsr  p8b_main.p8s_start |  lda  #0 |  sta ${"$"}ff00")
-                // TODO c128: how to bank basic+kernal back in?
+                asmgen.out("  jmp  sys.cleanup_at_exit")
-                if(!options.noSysInit)
-                    asmgen.out("  jmp  ${compTarget.name}.cleanup_at_exit")
-                else
-                    asmgen.out("  rts")
             }
-            else -> asmgen.jmp("main.start")
+            else -> asmgen.jmp("p8b_main.p8s_start")
         }
     }
 
     private fun memorySlabs() {
-        asmgen.out("; memory slabs")
+        if(symboltable.allMemorySlabs.isNotEmpty()) {
-        asmgen.out("prog8_slabs\t.block")
+            asmgen.out("; memory slabs\n  .section slabs_BSS")
-        for(slab in symboltable.allMemorySlabs) {
+            asmgen.out("prog8_slabs\t.block")
-            if(slab.align>1u)
+            for (slab in symboltable.allMemorySlabs) {
-                asmgen.out("\t.align  ${slab.align.toHex()}")
+                if (slab.align > 1u)
-            asmgen.out("${slab.name}\t.fill  ${slab.size}")
+                    asmgen.out("\t.align  ${slab.align.toHex()}")
+                asmgen.out("${slab.name}\t.fill  ${slab.size}")
+            }
+            asmgen.out("\t.bend\n  .send slabs_BSS")
         }
-        asmgen.out("\t.bend")
     }
 
     private fun footer() {
-        // program end
+        var relocateBssVars = false
-        asmgen.out("prog8_program_end\t; end of program label for progend()")
+        var relocateBssSlabs = false
+        var relocatedBssStart = 0u
+        var relocatedBssEnd = 0u
+
+        if(options.varsGolden) {
+            if(options.compTarget.machine.BSSGOLDENRAM_START == 0u ||
+                options.compTarget.machine.BSSGOLDENRAM_END == 0u ||
+                options.compTarget.machine.BSSGOLDENRAM_END <= options.compTarget.machine.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.machine.BSSGOLDENRAM_START
+            relocatedBssEnd = options.compTarget.machine.BSSGOLDENRAM_END
+        }
+        else if(options.varsHighBank!=null) {
+            if(options.compTarget.machine.BSSHIGHRAM_START == 0u ||
+                options.compTarget.machine.BSSHIGHRAM_END == 0u ||
+                options.compTarget.machine.BSSHIGHRAM_END <= options.compTarget.machine.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.machine.BSSHIGHRAM_START
+            relocatedBssEnd = options.compTarget.machine.BSSHIGHRAM_END
+        }
+
+        if(options.slabsGolden) {
+            if(options.compTarget.machine.BSSGOLDENRAM_START == 0u ||
+                options.compTarget.machine.BSSGOLDENRAM_END == 0u ||
+                options.compTarget.machine.BSSGOLDENRAM_END <= options.compTarget.machine.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.machine.BSSGOLDENRAM_START
+            relocatedBssEnd = options.compTarget.machine.BSSGOLDENRAM_END
+        }
+        else if(options.slabsHighBank!=null) {
+            if(options.compTarget.machine.BSSHIGHRAM_START == 0u ||
+                options.compTarget.machine.BSSHIGHRAM_END == 0u ||
+                options.compTarget.machine.BSSHIGHRAM_END <= options.compTarget.machine.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.machine.BSSHIGHRAM_START
+            relocatedBssEnd = options.compTarget.machine.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("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("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\"")
+            }
+        }
     }
 
-    private fun block2asm(block: Block) {
+    private fun block2asm(block: PtBlock) {
         asmgen.out("")
         asmgen.out("; ---- block: '${block.name}' ----")
-        if(block.address!=null)
+        if(block.options.address!=null)
-            asmgen.out("* = ${block.address!!.toHex()}")
+            asmgen.out("* = ${block.options.address!!.toHex()}")
         else {
-            if("align_word" in block.options())
+            if(block.options.alignment==PtBlock.BlockAlignment.WORD)
                 asmgen.out("\t.align 2")
-            else if("align_page" in block.options())
+            else if(block.options.alignment==PtBlock.BlockAlignment.PAGE)
                 asmgen.out("\t.align $100")
         }
 
-        asmgen.out("${block.name}\t" + (if("force_output" in block.options()) ".block\n" else ".proc\n"))
+        asmgen.out("${block.name}\t" + (if(block.options.forceOutput) ".block" else ".proc"))
         asmgen.outputSourceLine(block)
 
         createBlockVariables(block)
-        asmsubs2asm(block.statements)
+        asmsubs2asm(block.children)
 
         asmgen.out("")
 
         val initializers = blockVariableInitializers.getValue(block)
-        val notInitializers = block.statements.filterNot { it in initializers }
+        val notInitializers = block.children.filterNot { it in initializers }
         notInitializers.forEach { asmgen.translate(it) }
 
-        if(!options.dontReinitGlobals) {
+        // generate subroutine to initialize block-level (global) variables
-            // generate subroutine to initialize block-level (global) variables
+        if (initializers.isNotEmpty()) {
-            if (initializers.isNotEmpty()) {
+            asmgen.out("prog8_init_vars\t.block")
-                asmgen.out("prog8_init_vars\t.block\n")
+            initializers.forEach { assign ->
-                initializers.forEach { assign -> asmgen.translate(assign) }
+                if((assign.value as? PtNumber)?.number != 0.0 || allocator.isZpVar(assign.target.identifier!!.name))
-                asmgen.out("  rts\n  .bend")
+                    asmgen.translate(assign)
+                // the other variables that should be set to zero are done so as part of the BSS section.
             }
+            asmgen.out("  rts\n  .bend")
         }
 
-        asmgen.out(if("force_output" in block.options()) "\n\t.bend\n" else "\n\t.pend\n")
+        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: Block) {
+    private fun createBlockVariables(block: PtBlock) {
-        val scope = symboltable.lookupOrElse(block.name) { throw AssemblyError("lookup") }
+        val scope = symboltable.lookupUnscopedOrElse(block.name) { throw AssemblyError("lookup") }
         require(scope.type==StNodeType.BLOCK)
         val varsInBlock = getVars(scope)
 
@@ -247,26 +311,16 @@ internal class ProgramAndVarsGen(
         nonZpVariables2asm(variables)
     }
 
-    internal fun translateSubroutine(sub: Subroutine) {
+    internal fun translateAsmSubroutine(sub: PtAsmSub) {
-        var onlyVariables = false
-
         if(sub.inline) {
-            if(options.optimize) {
+            return      // subroutine gets inlined at call site.
-                if(sub.isAsmSubroutine || callGraph.unused(sub))
-                    return
-
-                // from an inlined subroutine only the local variables are generated,
-                // all other code statements are omitted in the subroutine itself
-                // (they've been inlined at the call site, remember?)
-                onlyVariables = true
-            }
         }
 
         asmgen.out("")
 
         val asmStartScope: String
         val asmEndScope: String
-        if(sub.definingBlock.options().contains("force_output")) {
+        if(sub.definingBlock()!!.options.forceOutput) {
             asmStartScope = ".block"
             asmEndScope = ".bend"
         } else {
@@ -274,105 +328,126 @@ internal class ProgramAndVarsGen(
             asmEndScope = ".pend"
         }
 
-        if(sub.isAsmSubroutine) {
+        if(sub.address!=null)
-            if(sub.asmAddress!=null)
+            return  // already done at the memvars section
-                return  // already done at the memvars section
 
-            // asmsub with most likely just an inline asm in it
+        // asmsub with most likely just an inline asm in it
-            asmgen.out("${sub.name}\t$asmStartScope")
+        asmgen.out("${sub.name}\t$asmStartScope")
-            sub.statements.forEach { asmgen.translate(it) }
+        sub.children.forEach { asmgen.translate(it) }
-            asmgen.out("  $asmEndScope\n")
+        asmgen.out("  $asmEndScope")
+    }
+
+
+    internal fun translateSubroutine(sub: PtSub) {
+        asmgen.out("")
+
+        val asmStartScope: String
+        val asmEndScope: String
+        if(sub.definingBlock()!!.options.forceOutput) {
+            asmStartScope = ".block"
+            asmEndScope = ".bend"
         } else {
-            // regular subroutine
+            asmStartScope = ".proc"
-            asmgen.out("${sub.name}\t$asmStartScope")
+            asmEndScope = ".pend"
-
-            val scope = symboltable.lookupOrElse(sub.scopedName) { throw AssemblyError("lookup") }
-            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.statements)
-
-            // the main.start subroutine is the program's entrypoint and should perform some initialization logic
-            if(sub.name=="start" && sub.definingBlock.name=="main")
-                entrypointInitialization()
-
-            if(functioncallAsmGen.optimizeIntArgsViaRegisters(sub)) {
-                asmgen.out("; simple int arg(s) passed via register(s)")
-                if(sub.parameters.size==1) {
-                    val dt = sub.parameters[0].type
-                    val target = AsmAssignTarget(TargetStorageKind.VARIABLE, asmgen, dt, sub, variableAsmName = sub.parameters[0].name)
-                    if(dt in ByteDatatypes)
-                        asmgen.assignRegister(RegisterOrPair.A, target)
-                    else
-                        asmgen.assignRegister(RegisterOrPair.AY, target)
-                } else {
-                    require(sub.parameters.size==2)
-                    // 2 simple byte args, first in A, second in Y
-                    val target1 = AsmAssignTarget(TargetStorageKind.VARIABLE, asmgen, sub.parameters[0].type, sub, variableAsmName = sub.parameters[0].name)
-                    val target2 = AsmAssignTarget(TargetStorageKind.VARIABLE, asmgen, sub.parameters[1].type, sub, variableAsmName = sub.parameters[1].name)
-                    asmgen.assignRegister(RegisterOrPair.A, target1)
-                    asmgen.assignRegister(RegisterOrPair.Y, target2)
-                }
-            }
-
-            if(!onlyVariables) {
-                asmgen.out("; statements")
-                sub.statements.forEach { asmgen.translate(it) }
-            }
-
-            asmgen.out("; variables")
-            val asmGenInfo = asmgen.subroutineExtra(sub)
-            for((dt, name, addr) in asmGenInfo.extraVars) {
-                if(addr!=null)
-                    asmgen.out("$name = $addr")
-                else when(dt) {
-                    DataType.UBYTE -> asmgen.out("$name    .byte  0")
-                    DataType.UWORD -> asmgen.out("$name    .word  0")
-                    else -> throw AssemblyError("weird dt")
-                }
-            }
-            if(asmGenInfo.usedRegsaveA)      // will probably never occur
-                asmgen.out("prog8_regsaveA     .byte  0")
-            if(asmGenInfo.usedRegsaveX)
-                asmgen.out("prog8_regsaveX     .byte  0")
-            if(asmGenInfo.usedRegsaveY)
-                asmgen.out("prog8_regsaveY     .byte  0")
-            if(asmGenInfo.usedFloatEvalResultVar1)
-                asmgen.out("$subroutineFloatEvalResultVar1    .byte  0,0,0,0,0")
-            if(asmGenInfo.usedFloatEvalResultVar2)
-                asmgen.out("$subroutineFloatEvalResultVar2    .byte  0,0,0,0,0")
-
-            // 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("  $asmEndScope\n")
         }
+
+        asmgen.out("${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()
+
+        if(functioncallAsmGen.optimizeIntArgsViaRegisters(sub)) {
+            asmgen.out("; simple int arg(s) passed via register(s)")
+            if(sub.parameters.size==1) {
+                val dt = sub.parameters[0].type
+                val target = AsmAssignTarget(TargetStorageKind.VARIABLE, asmgen, dt, sub, sub.parameters[0].position, variableAsmName = sub.parameters[0].name)
+                if(dt in ByteDatatypes)
+                    asmgen.assignRegister(RegisterOrPair.A, target)
+                else
+                    asmgen.assignRegister(RegisterOrPair.AY, target)
+            } else {
+                require(sub.parameters.size==2)
+                // 2 simple byte args, first in A, second in Y
+                val target1 = AsmAssignTarget(TargetStorageKind.VARIABLE, asmgen, sub.parameters[0].type, sub, sub.parameters[0].position, variableAsmName = sub.parameters[0].name)
+                val target2 = AsmAssignTarget(TargetStorageKind.VARIABLE, asmgen, sub.parameters[1].type, sub, sub.parameters[1].position, variableAsmName = sub.parameters[1].name)
+                asmgen.assignRegister(RegisterOrPair.A, target1)
+                asmgen.assignRegister(RegisterOrPair.Y, target2)
+            }
+        }
+
+        asmgen.out("; statements")
+        sub.children.forEach { asmgen.translate(it) }
+
+        asmgen.out("; variables")
+        asmgen.out("    .section BSS")
+        val asmGenInfo = asmgen.subroutineExtra(sub)
+        for((dt, name, addr) in asmGenInfo.extraVars) {
+            if(addr!=null)
+                asmgen.out("$name = $addr")
+            else when(dt) {
+                DataType.UBYTE -> asmgen.out("$name    .byte  ?")
+                DataType.UWORD -> asmgen.out("$name    .word  ?")
+                DataType.FLOAT -> asmgen.out("$name    .fill  ${options.compTarget.machine.FLOAT_MEM_SIZE}")
+                else -> throw AssemblyError("weird dt for extravar $dt")
+            }
+        }
+        if(asmGenInfo.usedFloatEvalResultVar1)
+            asmgen.out("$subroutineFloatEvalResultVar1    .fill  ${options.compTarget.machine.FLOAT_MEM_SIZE}")
+        if(asmGenInfo.usedFloatEvalResultVar2)
+            asmgen.out("$subroutineFloatEvalResultVar2    .fill  ${options.compTarget.machine.FLOAT_MEM_SIZE}")
+        asmgen.out("  .send BSS")
+
+        // 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() {
         asmgen.out("; program startup initialization")
-        asmgen.out("  cld")
+        asmgen.out("  cld |  tsx |  stx  prog8_lib.orig_stackpointer    ; required for sys.exit()")
-        if(!options.dontReinitGlobals) {
+        // set full BSS area to zero
-            blockVariableInitializers.forEach {
+        asmgen.out("""
-                if (it.value.isNotEmpty())
+    .if  prog8_bss_section_size>0
-                    asmgen.out("  jsr  ${it.key.name}.prog8_init_vars")
+    ; reset all variables in BSS section to zero
-            }
+	lda  #<prog8_bss_section_start
+	ldy  #>prog8_bss_section_start
+	sta  P8ZP_SCRATCH_W1
+	sty  P8ZP_SCRATCH_W1+1
+	ldx  #<prog8_bss_section_size
+	ldy  #>prog8_bss_section_size
+	lda  #0
+	jsr  prog8_lib.memset
+    .endif""")
+
+        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
@@ -397,12 +472,12 @@ internal class ProgramAndVarsGen(
                 asmgen.out("""
                     lda  #<${name}_init_value
                     ldy  #>${name}_init_value
-                    sta  cx16.r0L
+                    sta  cx16.r0
-                    sty  cx16.r0H
+                    sty  cx16.r0+1
                     lda  #<${name}
                     ldy  #>${name}
-                    sta  cx16.r1L
+                    sta  cx16.r1
-                    sty  cx16.r1H
+                    sty  cx16.r1+1
                     lda  #<$size
                     ldy  #>$size
                     jsr  sys.memcopy""")
@@ -420,21 +495,19 @@ internal class ProgramAndVarsGen(
             arrayVariable2asm(varname, it.alloc.dt, it.value, null)
         }
 
-        asmgen.out("""+       tsx
+        asmgen.out("""+        
-                    stx  prog8_lib.orig_stackpointer    ; required for sys.exit()                    
-                    ldx  #255       ; init estack ptr
                     clv
                     clc""")
     }
 
     private class ZpStringWithInitial(
-        val name: List<String>,
+        val name: String,
         val alloc: MemoryAllocator.VarAllocation,
         val value: Pair<String, Encoding>
     )
 
     private class ZpArrayWithInitial(
-        val name: List<String>,
+        val name: String,
         val alloc: MemoryAllocator.VarAllocation,
         val value: StArray
     )
@@ -443,9 +516,10 @@ internal class ProgramAndVarsGen(
         val result = mutableListOf<ZpStringWithInitial>()
         val vars = allocator.zeropageVars.filter { it.value.dt==DataType.STR }
         for (variable in vars) {
-            val svar = symboltable.flat.getValue(variable.key) as StStaticVariable
+            val scopedName = variable.key
-            if(svar.onetimeInitializationStringValue!=null)
+            val svar = symboltable.lookup(scopedName) as? StStaticVariable
-                result.add(ZpStringWithInitial(variable.key, variable.value, svar.onetimeInitializationStringValue!!))
+            if(svar?.onetimeInitializationStringValue!=null)
+                result.add(ZpStringWithInitial(scopedName, variable.value, svar.onetimeInitializationStringValue!!))
         }
         return result
     }
@@ -454,36 +528,82 @@ internal class ProgramAndVarsGen(
         val result = mutableListOf<ZpArrayWithInitial>()
         val vars = allocator.zeropageVars.filter { it.value.dt in ArrayDatatypes }
         for (variable in vars) {
-            val svar = symboltable.flat.getValue(variable.key) as StStaticVariable
+            val scopedName = variable.key
-            if(svar.onetimeInitializationArrayValue!=null)
+            val svar = symboltable.lookup(scopedName) as? StStaticVariable
-                result.add(ZpArrayWithInitial(variable.key, variable.value, svar.onetimeInitializationArrayValue!!))
+            if(svar?.onetimeInitializationArrayValue!=null)
+                result.add(ZpArrayWithInitial(scopedName, variable.value, svar.onetimeInitializationArrayValue!!))
         }
         return result
     }
 
-    private fun zeropagevars2asm(varNames: Set<List<String>>) {
+    private fun zeropagevars2asm(varNames: Set<String>) {
-        val zpVariables = allocator.zeropageVars.filter { it.key in varNames }
+        val zpVariables = allocator.zeropageVars.filter { it.key in varNames }.toList().sortedBy { it.second.address }
         for ((scopedName, zpvar) in zpVariables) {
-            if (scopedName.size == 2 && scopedName[0] == "cx16" && scopedName[1][0] == 'r' && scopedName[1][1].isDigit())
+            if (scopedName.startsWith("cx16.r"))
                 continue        // The 16 virtual registers of the cx16 are not actual variables in zp, they're memory mapped
-            asmgen.out("${scopedName.last()} \t= ${zpvar.address} \t; zp ${zpvar.dt}")
+            val variable = symboltable.flat.getValue(scopedName) as StStaticVariable
+            if(variable.dt in SplitWordArrayTypes) {
+                val lsbAddr = zpvar.address
+                val msbAddr = zpvar.address + (zpvar.size/2).toUInt()
+                asmgen.out("${scopedName.substringAfterLast('.')}_lsb \t= $lsbAddr \t; zp ${zpvar.dt} (lsbs)")
+                asmgen.out("${scopedName.substringAfterLast('.')}_msb \t= $msbAddr \t; zp ${zpvar.dt} (msbs)")
+            } else {
+                asmgen.out("${scopedName.substringAfterLast('.')} \t= ${zpvar.address} \t; zp ${zpvar.dt}")
+            }
         }
     }
 
     private fun nonZpVariables2asm(variables: List<StStaticVariable>) {
         asmgen.out("")
-        asmgen.out("; non-zeropage variables")
+        val (varsNoInit, varsWithInit) = variables.partition { it.uninitialized }
-        val (stringvars, othervars) = variables.partition { it.dt==DataType.STR }
+        if(varsNoInit.isNotEmpty()) {
-        stringvars.forEach {
+            asmgen.out("; non-zeropage variables without initialization value")
-            outputStringvar(it.name, it.onetimeInitializationStringValue!!.second, it.onetimeInitializationStringValue!!.first)
+            asmgen.out("  .section BSS")
+            varsNoInit.sortedWith(compareBy<StStaticVariable> { it.name }.thenBy { it.dt }).forEach {
+                uninitializedVariable2asm(it)
+            }
+            asmgen.out("  .send BSS")
         }
-        othervars.sortedBy { it.type }.forEach {
+
-            staticVariable2asm(it)
+        if(varsWithInit.isNotEmpty()) {
+            asmgen.out("; non-zeropage variables")
+            val (stringvars, othervars) = varsWithInit.sortedBy { it.name }.partition { it.dt == DataType.STR }
+            stringvars.forEach {
+                outputStringvar(
+                    it.name,
+                    it.onetimeInitializationStringValue!!.second,
+                    it.onetimeInitializationStringValue!!.first
+                )
+            }
+            othervars.sortedBy { it.type }.forEach {
+                staticVariable2asm(it)
+            }
+        }
+    }
+
+    private fun uninitializedVariable2asm(variable: StStaticVariable) {
+        when (variable.dt) {
+            DataType.UBYTE -> asmgen.out("${variable.name}\t.byte  ?")
+            DataType.BYTE -> asmgen.out("${variable.name}\t.char  ?")
+            DataType.UWORD -> asmgen.out("${variable.name}\t.word  ?")
+            DataType.WORD -> asmgen.out("${variable.name}\t.sint  ?")
+            DataType.FLOAT -> asmgen.out("${variable.name}\t.fill  ${compTarget.machine.FLOAT_MEM_SIZE}")
+            in SplitWordArrayTypes -> {
+                val numbytesPerHalf = compTarget.memorySize(variable.dt, variable.length!!) / 2
+                asmgen.out("${variable.name}_lsb\t.fill  $numbytesPerHalf")
+                asmgen.out("${variable.name}_msb\t.fill  $numbytesPerHalf")
+            }
+            in ArrayDatatypes -> {
+                val numbytes = compTarget.memorySize(variable.dt, variable.length!!)
+                asmgen.out("${variable.name}\t.fill  $numbytes")
+            }
+            else -> {
+                throw AssemblyError("weird dt")
+            }
         }
     }
 
     private fun staticVariable2asm(variable: StStaticVariable) {
-        val name = variable.name
         val initialValue: Number =
             if(variable.onetimeInitializationNumericValue!=null) {
                 if(variable.dt== DataType.FLOAT)
@@ -493,22 +613,22 @@ internal class ProgramAndVarsGen(
             } else 0
 
         when (variable.dt) {
-            DataType.UBYTE -> asmgen.out("$name\t.byte  ${initialValue.toHex()}")
+            DataType.UBYTE -> asmgen.out("${variable.name}\t.byte  ${initialValue.toHex()}")
-            DataType.BYTE -> asmgen.out("$name\t.char  $initialValue")
+            DataType.BYTE -> asmgen.out("${variable.name}\t.char  $initialValue")
-            DataType.UWORD -> asmgen.out("$name\t.word  ${initialValue.toHex()}")
+            DataType.UWORD -> asmgen.out("${variable.name}\t.word  ${initialValue.toHex()}")
-            DataType.WORD -> asmgen.out("$name\t.sint  $initialValue")
+            DataType.WORD -> asmgen.out("${variable.name}\t.sint  $initialValue")
             DataType.FLOAT -> {
                 if(initialValue==0) {
-                    asmgen.out("$name\t.byte  0,0,0,0,0  ; float")
+                    asmgen.out("${variable.name}\t.byte  0,0,0,0,0  ; float")
                 } else {
                     val floatFill = compTarget.machine.getFloatAsmBytes(initialValue)
-                    asmgen.out("$name\t.byte  $floatFill  ; float $initialValue")
+                    asmgen.out("${variable.name}\t.byte  $floatFill  ; float $initialValue")
                 }
             }
             DataType.STR -> {
                 throw AssemblyError("all string vars should have been interned into prog")
             }
-            in ArrayDatatypes -> arrayVariable2asm(name, variable.dt, variable.onetimeInitializationArrayValue, variable.length)
+            in ArrayDatatypes -> arrayVariable2asm(variable.name, variable.dt, variable.onetimeInitializationArrayValue, variable.length)
             else -> {
                 throw AssemblyError("weird dt")
             }
@@ -557,6 +677,18 @@ internal class ProgramAndVarsGen(
                         asmgen.out("  .sint  " + chunk.joinToString())
                 }
             }
+            DataType.ARRAY_UW_SPLIT -> {
+                val data = makeArrayFillDataUnsigned(dt, value, orNumberOfZeros)
+                asmgen.out("_array_$varname := ${data.joinToString()}")
+                asmgen.out("${varname}_lsb\t.byte <_array_$varname")
+                asmgen.out("${varname}_msb\t.byte >_array_$varname")
+            }
+            DataType.ARRAY_W_SPLIT -> {
+                val data = makeArrayFillDataSigned(dt, value, orNumberOfZeros)
+                asmgen.out("_array_$varname := ${data.joinToString()}")
+                asmgen.out("${varname}_lsb\t.byte <_array_$varname")
+                asmgen.out("${varname}_msb\t.byte >_array_$varname")
+            }
             DataType.ARRAY_F -> {
                 val array = value ?: zeroFilledArray(orNumberOfZeros!!)
                 val floatFills = array.map {
@@ -579,10 +711,10 @@ internal class ProgramAndVarsGen(
     }
 
     private fun memdefsAndConsts2asm(memvars: Collection<StMemVar>, consts: Collection<StConstant>) {
-        memvars.forEach {
+        memvars.sortedBy { it.address }.forEach {
             asmgen.out("  ${it.name} = ${it.address.toHex()}")
         }
-        consts.forEach {
+        consts.sortedBy { it.name }.forEach {
             if(it.dt==DataType.FLOAT)
                 asmgen.out("  ${it.name} = ${it.value}")
             else
@@ -590,12 +722,12 @@ internal class ProgramAndVarsGen(
         }
     }
 
-    private fun asmsubs2asm(statements: List<Statement>) {
+    private fun asmsubs2asm(statements: List<PtNode>) {
         statements
-            .filter { it is Subroutine && it.isAsmSubroutine && it.asmAddress!=null }
+            .filter { it is PtAsmSub && it.address!=null }
             .forEach { asmsub ->
-                asmsub as Subroutine
+                asmsub as PtAsmSub
-                asmgen.out("  ${asmsub.name} = ${asmsub.asmAddress!!.toHex()}")
+                asmgen.out("  ${asmsub.name} = ${asmsub.address!!.toHex()}")
             }
     }
 
@@ -616,12 +748,12 @@ internal class ProgramAndVarsGen(
                     val number = it.number!!.toInt()
                     "$"+number.toString(16).padStart(2, '0')
                 }
-            DataType.ARRAY_UW -> array.map {
+            DataType.ARRAY_UW, DataType.ARRAY_UW_SPLIT -> array.map {
                 if(it.number!=null) {
                     "$" + it.number!!.toInt().toString(16).padStart(4, '0')
                 }
-                else if(it.addressOf!=null) {
+                else if(it.addressOfSymbol!=null) {
-                    asmgen.asmSymbolName(it.addressOf!!)
+                    asmgen.asmSymbolName(it.addressOfSymbol!!)
                 }
                 else
                     throw AssemblyError("weird array elt")
@@ -648,11 +780,11 @@ internal class ProgramAndVarsGen(
                     else
                         "-$$hexnum"
                 }
-            DataType.ARRAY_UW -> array.map {
+            DataType.ARRAY_UW, DataType.ARRAY_UW_SPLIT -> array.map {
                 val number = it.number!!.toInt()
                 "$" + number.toString(16).padStart(4, '0')
             }
-            DataType.ARRAY_W -> array.map {
+            DataType.ARRAY_W, DataType.ARRAY_W_SPLIT -> array.map {
                 val number = it.number!!.toInt()
                 val hexnum = number.absoluteValue.toString(16).padStart(4, '0')
                 if(number>=0)

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

@@ -16,13 +16,14 @@ internal class VariableAllocator(private val symboltable: SymbolTable,
 
     private val zeropage = options.compTarget.machine.zeropage
     internal val globalFloatConsts = mutableMapOf<Double, String>()     // all float values in the entire program (value -> varname)
-    internal val zeropageVars: Map<List<String>, MemoryAllocator.VarAllocation> = zeropage.allocatedVariables
+    internal val zeropageVars: Map<String, MemoryAllocator.VarAllocation>
 
     init {
         allocateZeropageVariables()
+        zeropageVars = zeropage.allocatedVariables
     }
 
-    internal fun isZpVar(scopedName: List<String>) = scopedName in zeropage.allocatedVariables
+    internal fun isZpVar(scopedName: String) = scopedName in zeropageVars
 
     internal fun getFloatAsmConst(number: Double): String {
         val asmName = globalFloatConsts[number]
@@ -59,7 +60,7 @@ internal class VariableAllocator(private val symboltable: SymbolTable,
                 variable.scopedName,
                 variable.dt,
                 variable.length,
-                variable.position,
+                variable.astNode.position,
                 errors
             )
             result.fold(
@@ -67,7 +68,7 @@ internal class VariableAllocator(private val symboltable: SymbolTable,
                     numVariablesAllocatedInZP++
                 },
                 failure = {
-                    errors.err(it.message!!, variable.position)
+                    errors.err(it.message!!, variable.astNode.position)
                 }
             )
         }
@@ -78,7 +79,7 @@ internal class VariableAllocator(private val symboltable: SymbolTable,
                     variable.scopedName,
                     variable.dt,
                     variable.length,
-                    variable.position,
+                    variable.astNode.position,
                     errors
                 )
                 result.onSuccess { numVariablesAllocatedInZP++ }
@@ -88,7 +89,8 @@ internal class VariableAllocator(private val symboltable: SymbolTable,
             // try to allocate any other 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()) {
-                for (variable in varsDontCare.sortedBy { it.scopedName.size }) {
+                val sortedList = varsDontCare.sortedByDescending { it.scopedName }
+                for (variable in sortedList) {
                     if(variable.dt in IntegerDatatypes) {
                         if(zeropage.free.isEmpty()) {
                             break
@@ -97,7 +99,7 @@ internal class VariableAllocator(private val symboltable: SymbolTable,
                                 variable.scopedName,
                                 variable.dt,
                                 variable.length,
-                                variable.position,
+                                variable.astNode.position,
                                 errors
                             )
                             result.onSuccess { numVariablesAllocatedInZP++ }
@@ -124,6 +126,6 @@ internal class VariableAllocator(private val symboltable: SymbolTable,
             }
         }
         collect(st)
-        return vars
+        return vars.sortedBy { it.dt }
     }
 }

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

@@ -0,0 +1,253 @@
+package prog8.codegen.cpu6502.assignment
+
+import prog8.code.ast.PtBinaryExpression
+import prog8.code.ast.PtExpression
+import prog8.code.core.*
+import prog8.code.target.C64Target
+import prog8.code.target.Cx16Target
+import prog8.codegen.cpu6502.AsmGen6502Internal
+
+//
+// This contains codegen for stack-based evaluation of binary expressions.
+// It uses the CPU stack so depth is limited.
+// It is called "as a last resort" if the optimized codegen path is unable
+// to come up with a special case of the expression.
+//
+internal class AnyExprAsmGen(
+    private val asmgen: AsmGen6502Internal
+) {
+    fun assignAnyExpressionUsingStack(expr: PtBinaryExpression, assign: AsmAssignment): Boolean {
+        when(expr.type) {
+            in ByteDatatypes -> {
+                if(expr.left.type in ByteDatatypes && expr.right.type in ByteDatatypes)
+                    return assignByteBinExpr(expr, assign)
+                if (expr.left.type in WordDatatypes && expr.right.type in WordDatatypes) {
+                    require(expr.operator in ComparisonOperators)
+                    throw AssemblyError("words operands comparison -> byte, should have been handled by assignOptimizedComparisonWords()")
+                }
+                if (expr.left.type==DataType.FLOAT && expr.right.type==DataType.FLOAT) {
+                    require(expr.operator in ComparisonOperators)
+                    return assignFloatBinExpr(expr, assign)
+                }
+                throw AssemblyError("weird expr operand types: ${expr.left.type} and ${expr.right.type}")
+            }
+            in WordDatatypes -> {
+                require(expr.left.type in WordDatatypes && expr.right.type in WordDatatypes) {
+                    "both operands must be words"
+                }
+                return assignWordBinExpr(expr)
+            }
+            DataType.FLOAT -> {
+                require(expr.left.type==DataType.FLOAT && expr.right.type==DataType.FLOAT) {
+                    "both operands must be floats"
+                }
+                return assignFloatBinExpr(expr, assign)
+            }
+            else -> throw AssemblyError("weird expression type in assignment")
+        }
+    }
+
+    private fun assignWordBinExpr(expr: PtBinaryExpression): Boolean {
+        when(expr.operator) {
+            "+" -> TODO("word + at ${expr.position}")
+            "-" -> TODO("word - at ${expr.position}")
+            "*" -> TODO("word * at ${expr.position}")
+            "/" -> TODO("word / at ${expr.position}")
+            "<<" -> TODO("word << at ${expr.position}")
+            ">>" -> TODO("word >> at ${expr.position}")
+            "%" -> TODO("word % at ${expr.position}")
+            "and" -> TODO("word logical and (with optional shortcircuit) ${expr.position}")
+            "or" -> TODO("word logical or (with optional shortcircuit) ${expr.position}")
+            "&" -> TODO("word and at ${expr.position}")
+            "|" -> TODO("word or at ${expr.position}")
+            "^", "xor" -> TODO("word xor at ${expr.position}")
+            "==" -> TODO("word == at ${expr.position}")
+            "!=" -> TODO("word != at ${expr.position}")
+            "<" -> TODO("word < at ${expr.position}")
+            "<=" -> TODO("word <= at ${expr.position}")
+            ">" -> TODO("word > at ${expr.position}")
+            ">=" -> TODO("word >= at ${expr.position}")
+            else -> return false
+        }
+    }
+
+    private fun assignByteBinExpr(expr: PtBinaryExpression, assign: AsmAssignment): Boolean {
+        when(expr.operator) {
+            "+" -> {
+                asmgen.assignExpressionToRegister(expr.left, RegisterOrPair.A, false)
+                asmgen.out("  pha")
+                asmgen.assignExpressionToVariable(expr.right, "P8ZP_SCRATCH_B1", DataType.UBYTE)
+                asmgen.out("  pla |  clc |  adc  P8ZP_SCRATCH_B1")
+                asmgen.assignRegister(RegisterOrPair.A, assign.target)
+                return true
+            }
+            "-" -> {
+                asmgen.assignExpressionToRegister(expr.left, RegisterOrPair.A, false)
+                asmgen.out("  pha")
+                asmgen.assignExpressionToVariable(expr.right, "P8ZP_SCRATCH_B1", DataType.UBYTE)
+                asmgen.out("  pla |  sec |  sbc  P8ZP_SCRATCH_B1")
+                asmgen.assignRegister(RegisterOrPair.A, assign.target)
+                return true
+            }
+            "*" -> {
+                TODO("byte * at ${expr.position}")
+            }
+            "/" -> {
+                TODO("byte / at ${expr.position}")
+            }
+            "<<" -> {
+                TODO("byte << at ${expr.position}")
+            }
+            ">>" -> {
+                TODO("byte >> at ${expr.position}")
+            }
+            "%" -> {
+                TODO("byte % at ${expr.position}")
+            }
+            "and" -> TODO("logical and (with optional shortcircuit) ${expr.position}")
+            "or" -> TODO("logical or (with optional shortcircuit) ${expr.position}")
+            "&" -> {
+                asmgen.assignExpressionToRegister(expr.left, RegisterOrPair.A, false)
+                asmgen.out("  pha")
+                asmgen.assignExpressionToVariable(expr.right, "P8ZP_SCRATCH_B1", DataType.UBYTE)
+                asmgen.out("  pla |  and  P8ZP_SCRATCH_B1")
+                asmgen.assignRegister(RegisterOrPair.A, assign.target)
+                return true
+            }
+            "|" -> {
+                asmgen.assignExpressionToRegister(expr.left, RegisterOrPair.A, false)
+                asmgen.out("  pha")
+                asmgen.assignExpressionToVariable(expr.right, "P8ZP_SCRATCH_B1", DataType.UBYTE)
+                asmgen.out("  pla |  ora  P8ZP_SCRATCH_B1")
+                asmgen.assignRegister(RegisterOrPair.A, assign.target)
+                return true
+            }
+            "^", "xor" -> {
+                asmgen.assignExpressionToRegister(expr.left, RegisterOrPair.A, false)
+                asmgen.out("  pha")
+                asmgen.assignExpressionToVariable(expr.right, "P8ZP_SCRATCH_B1", DataType.UBYTE)
+                asmgen.out("  pla |  eor  P8ZP_SCRATCH_B1")
+                asmgen.assignRegister(RegisterOrPair.A, assign.target)
+                return true
+            }
+            "==" -> {
+                TODO("byte == at ${expr.position}")
+            }
+            "!=" -> {
+                TODO("byte != at ${expr.position}")
+            }
+            "<" -> {
+                TODO("byte < at ${expr.position}")
+            }
+            "<=" -> {
+                TODO("byte <= at ${expr.position}")
+            }
+            ">" -> {
+                TODO("byte > at ${expr.position}")
+            }
+            ">=" -> {
+                TODO("byte >= at ${expr.position}")
+            }
+            else -> return false
+        }
+    }
+
+    private fun assignFloatBinExpr(expr: PtBinaryExpression, assign: AsmAssignment): Boolean {
+        when(expr.operator) {
+            "+" -> {
+                assignFloatOperandsToFACandARG(expr.left, expr.right)
+                asmgen.out("  jsr  floats.FADDT")
+                asmgen.assignRegister(RegisterOrPair.FAC1, assign.target)
+                return true
+            }
+            "-" -> {
+                assignFloatOperandsToFACandARG(expr.right, expr.left)
+                asmgen.out("  jsr  floats.FSUBT")
+                asmgen.assignRegister(RegisterOrPair.FAC1, assign.target)
+                return true
+            }
+            "*" -> {
+                assignFloatOperandsToFACandARG(expr.left, expr.right)
+                asmgen.out("  jsr  floats.FMULTT")
+                asmgen.assignRegister(RegisterOrPair.FAC1, assign.target)
+                return true
+            }
+            "/" -> {
+                assignFloatOperandsToFACandARG(expr.right, expr.left)
+                asmgen.out("  jsr  floats.FDIVT")
+                asmgen.assignRegister(RegisterOrPair.FAC1, assign.target)
+                return true
+            }
+            "==" -> {
+                setupFloatComparisonFAC1vsVarAY(expr)
+                asmgen.out("  jsr  floats.var_fac1_equal_f")
+                asmgen.assignRegister(RegisterOrPair.A, assign.target)
+                return true
+            }
+            "!=" -> {
+                setupFloatComparisonFAC1vsVarAY(expr)
+                asmgen.out("  jsr  floats.var_fac1_notequal_f")
+                asmgen.assignRegister(RegisterOrPair.A, assign.target)
+                return true
+            }
+            "<" -> {
+                setupFloatComparisonFAC1vsVarAY(expr)
+                asmgen.out("  jsr  floats.var_fac1_less_f")
+                asmgen.assignRegister(RegisterOrPair.A, assign.target)
+                return true
+            }
+            ">" -> {
+                setupFloatComparisonFAC1vsVarAY(expr)
+                asmgen.out("  jsr  floats.var_fac1_greater_f")
+                asmgen.assignRegister(RegisterOrPair.A, assign.target)
+                return true
+            }
+            "<=" -> {
+                setupFloatComparisonFAC1vsVarAY(expr)
+                asmgen.out("  jsr  floats.var_fac1_lesseq_f")
+                asmgen.assignRegister(RegisterOrPair.A, assign.target)
+                return true
+            }
+            ">=" -> {
+                setupFloatComparisonFAC1vsVarAY(expr)
+                asmgen.out("  jsr  floats.var_fac1_greatereq_f")
+                asmgen.assignRegister(RegisterOrPair.A, assign.target)
+                return true
+            }
+            else -> TODO("float expression operator ${expr.operator}")
+        }
+    }
+
+    private fun assignFloatOperandsToFACandARG(left: PtExpression, right: PtExpression) {
+        when(asmgen.options.compTarget.name) {
+            C64Target.NAME -> {
+                // c64 has a quirk: always make sure FAC2 is loaded last (done using CONUPK)  otherwise the result will be corrupt on C64
+                // this requires some more forced copying around of float values in certain cases
+                if (right.isSimple()) {
+                    asmgen.assignExpressionToRegister(left, RegisterOrPair.FAC1, true)
+                    asmgen.assignExpressionToRegister(right, RegisterOrPair.FAC2, true)
+                } else {
+                    asmgen.assignExpressionToRegister(right, RegisterOrPair.FAC1, true)
+                    asmgen.pushFAC1()
+                    asmgen.assignExpressionToRegister(left, RegisterOrPair.FAC1, true)
+                    asmgen.popFAC2()
+                }
+            }
+            Cx16Target.NAME -> {
+                asmgen.assignExpressionToRegister(left, RegisterOrPair.FAC1, true)
+                if (!right.isSimple()) asmgen.pushFAC1()
+                asmgen.assignExpressionToRegister(right, RegisterOrPair.FAC2, true)
+                if (!right.isSimple()) asmgen.popFAC1()
+            }
+            else -> TODO("don't know how to evaluate float expression for selected compilation target")
+        }
+    }
+
+    private fun setupFloatComparisonFAC1vsVarAY(expr: PtBinaryExpression) {
+        asmgen.assignExpressionToRegister(expr.left, RegisterOrPair.FAC1, true)
+        if(!expr.right.isSimple()) asmgen.pushFAC1()
+        asmgen.assignExpressionToVariable(expr.right, "floats.floats_temp_var", DataType.FLOAT)
+        if(!expr.right.isSimple()) asmgen.popFAC1()
+        asmgen.out("  lda  #<floats.floats_temp_var |  ldy  #>floats.floats_temp_var")
+    }
+}

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

@@ -1,21 +1,16 @@
 package prog8.codegen.cpu6502.assignment
 
-import prog8.ast.Program
+import prog8.code.ast.*
-import prog8.ast.expressions.*
-import prog8.ast.statements.AssignTarget
-import prog8.ast.statements.Assignment
-import prog8.ast.statements.DirectMemoryWrite
-import prog8.ast.statements.Subroutine
 import prog8.code.core.*
-import prog8.codegen.cpu6502.AsmGen
+import prog8.codegen.cpu6502.AsmGen6502Internal
+import prog8.codegen.cpu6502.returnsWhatWhere
 
 
 internal enum class TargetStorageKind {
     VARIABLE,
     ARRAY,
     MEMORY,
-    REGISTER,
+    REGISTER
-    STACK
 }
 
 internal enum class SourceStorageKind {
@@ -24,73 +19,69 @@ internal enum class SourceStorageKind {
     ARRAY,
     MEMORY,
     REGISTER,
-    STACK,              // value is already present on stack
     EXPRESSION,         // expression in ast-form, still to be evaluated
 }
 
 internal class AsmAssignTarget(val kind: TargetStorageKind,
-                               private val asmgen: AsmGen,
+                               private val asmgen: AsmGen6502Internal,
                                val datatype: DataType,
-                               val scope: Subroutine?,
+                               val scope: IPtSubroutine?,
+                               val position: Position,
                                private val variableAsmName: String? = null,
-                               val array: ArrayIndexedExpression? = null,
+                               val array: PtArrayIndexer? = null,
-                               val memory: DirectMemoryWrite? = null,
+                               val memory: PtMemoryByte? = null,
                                val register: RegisterOrPair? = null,
-                               val origAstTarget: AssignTarget? = null
+                               val origAstTarget: PtAssignTarget? = null
                                )
 {
-    val constArrayIndexValue by lazy { array?.indexer?.constIndex()?.toUInt() }
+    val constArrayIndexValue by lazy { array?.index?.asConstInteger()?.toUInt() }
     val asmVarname: String by lazy {
         if (array == null)
             variableAsmName!!
         else
-            asmgen.asmVariableName(array.arrayvar)
+            asmgen.asmVariableName(array.variable)
     }
 
-    lateinit var origAssign: AsmAssignment
-
     init {
         if(register!=null && datatype !in NumericDatatypes)
             throw AssemblyError("register must be integer or float type")
     }
 
     companion object {
-        fun fromAstAssignment(assign: Assignment, program: Program, asmgen: AsmGen): AsmAssignTarget {
+        fun fromAstAssignment(target: PtAssignTarget, definingSub: IPtSubroutine?, asmgen: AsmGen6502Internal): AsmAssignTarget {
-            with(assign.target) {
+            with(target) {
-                val idt = inferType(program)
-                val dt = idt.getOrElse { throw AssemblyError("unknown dt") }
                 when {
                     identifier != null -> {
-                        val parameter = identifier!!.targetVarDecl(program)?.subroutineParameter
+                        val parameter = asmgen.findSubroutineParameter(identifier!!.name, asmgen)
                         if (parameter!=null) {
-                            val sub = parameter.definingSubroutine!!
+                            val sub = parameter.definingAsmSub()
-                            if (sub.isAsmSubroutine) {
+                            if (sub!=null) {
-                                val reg = sub.asmParameterRegisters[sub.parameters.indexOf(parameter)]
+                                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, dt, assign.definingSubroutine, register=reg.registerOrPair, origAstTarget = this)
+                                    return AsmAssignTarget(TargetStorageKind.REGISTER, asmgen, type, definingSub, target.position, register=reg.registerOrPair, origAstTarget = this)
                             }
                         }
-                        return AsmAssignTarget(TargetStorageKind.VARIABLE, asmgen, dt, assign.definingSubroutine, variableAsmName = asmgen.asmVariableName(identifier!!), origAstTarget =  this)
+                        return AsmAssignTarget(TargetStorageKind.VARIABLE, asmgen, type, definingSub, target.position, variableAsmName = asmgen.asmVariableName(identifier!!), origAstTarget =  this)
                     }
-                    arrayindexed != null -> return AsmAssignTarget(TargetStorageKind.ARRAY, asmgen, dt, assign.definingSubroutine, array = arrayindexed, origAstTarget =  this)
+                    array != null -> return AsmAssignTarget(TargetStorageKind.ARRAY, asmgen, type, definingSub, target.position, array = array, origAstTarget =  this)
-                    memoryAddress != null -> return AsmAssignTarget(TargetStorageKind.MEMORY, asmgen, dt, assign.definingSubroutine, memory =  memoryAddress, 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, scope: Subroutine?, asmgen: AsmGen): AsmAssignTarget =
+        fun fromRegisters(registers: RegisterOrPair, signed: Boolean, pos: Position, scope: IPtSubroutine?, asmgen: AsmGen6502Internal): AsmAssignTarget =
                 when(registers) {
                     RegisterOrPair.A,
                     RegisterOrPair.X,
-                    RegisterOrPair.Y -> AsmAssignTarget(TargetStorageKind.REGISTER, asmgen, if(signed) DataType.BYTE else DataType.UBYTE, scope, register = registers)
+                    RegisterOrPair.Y -> AsmAssignTarget(TargetStorageKind.REGISTER, asmgen, if(signed) DataType.BYTE else DataType.UBYTE, scope, pos, register = registers)
                     RegisterOrPair.AX,
                     RegisterOrPair.AY,
-                    RegisterOrPair.XY -> AsmAssignTarget(TargetStorageKind.REGISTER, asmgen, if(signed) DataType.WORD else DataType.UWORD, scope, register = registers)
+                    RegisterOrPair.XY -> AsmAssignTarget(TargetStorageKind.REGISTER, asmgen, if(signed) DataType.WORD else DataType.UWORD, scope, pos, register = registers)
                     RegisterOrPair.FAC1,
-                    RegisterOrPair.FAC2 -> AsmAssignTarget(TargetStorageKind.REGISTER, asmgen, DataType.FLOAT, scope, register = registers)
+                    RegisterOrPair.FAC2 -> AsmAssignTarget(TargetStorageKind.REGISTER, asmgen, DataType.FLOAT, scope, pos, register = registers)
                     RegisterOrPair.R0,
                     RegisterOrPair.R1,
                     RegisterOrPair.R2,
@@ -106,75 +97,94 @@ internal class AsmAssignTarget(val kind: TargetStorageKind,
                     RegisterOrPair.R12,
                     RegisterOrPair.R13,
                     RegisterOrPair.R14,
-                    RegisterOrPair.R15 -> AsmAssignTarget(TargetStorageKind.REGISTER, asmgen, if(signed) DataType.WORD else DataType.UWORD, scope, register = registers)
+                    RegisterOrPair.R15 -> AsmAssignTarget(TargetStorageKind.REGISTER, asmgen, if(signed) DataType.WORD else DataType.UWORD, 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
+            }
+        }
 }
 
 internal class AsmAssignSource(val kind: SourceStorageKind,
-                               private val program: Program,
+                               private val program: PtProgram,
-                               private val asmgen: AsmGen,
+                               private val asmgen: AsmGen6502Internal,
                                val datatype: DataType,
                                private val variableAsmName: String? = null,
-                               val array: ArrayIndexedExpression? = null,
+                               val array: PtArrayIndexer? = null,
-                               val memory: DirectMemoryRead? = null,
+                               val memory: PtMemoryByte? = null,
                                val register: RegisterOrPair? = null,
-                               val number: NumericLiteral? = null,
+                               val number: PtNumber? = null,
-                               val expression: Expression? = null
+                               val expression: PtExpression? = null
 )
 {
     val asmVarname: String
         get() = if(array==null)
             variableAsmName!!
         else
-            asmgen.asmVariableName(array.arrayvar)
+            asmgen.asmVariableName(array.variable)
 
     companion object {
-        fun fromAstSource(value: Expression, program: Program, asmgen: AsmGen): AsmAssignSource {
+        fun fromAstSource(value: PtExpression, program: PtProgram, asmgen: AsmGen6502Internal): AsmAssignSource {
-            val cv = value.constValue(program)
+            val cv = value as? PtNumber
             if(cv!=null)
                 return AsmAssignSource(SourceStorageKind.LITERALNUMBER, program, asmgen, cv.type, number = cv)
 
             return when(value) {
-                is NumericLiteral -> throw AssemblyError("should have been constant value")
+                // checked above:   is PtNumber -> throw AssemblyError("should have been constant value")
-                is StringLiteral -> throw AssemblyError("string literal value should not occur anymore for asm generation")
+                is PtString -> throw AssemblyError("string literal value should not occur anymore for asm generation")
-                is ArrayLiteral -> throw AssemblyError("array literal value should not occur anymore for asm generation")
+                is PtArray -> throw AssemblyError("array literal value should not occur anymore for asm generation")
-                is IdentifierReference -> {
+                is PtIdentifier -> {
-                    val parameter = value.targetVarDecl(program)?.subroutineParameter
+                    val parameter = asmgen.findSubroutineParameter(value.name, asmgen)
-                    if(parameter!=null && parameter.definingSubroutine!!.isAsmSubroutine)
+                    if(parameter?.definingAsmSub() != null)
                         throw AssemblyError("can't assign from a asmsub register parameter $value ${value.position}")
-                    val dt = value.inferType(program).getOr(DataType.UNDEFINED)
                     val varName=asmgen.asmVariableName(value)
                     // special case: "cx16.r[0-15]" are 16-bits virtual registers of the commander X16 system
-                    if(dt == DataType.UWORD && varName.lowercase().startsWith("cx16.r")) {
+                    if(value.type == DataType.UWORD && varName.lowercase().startsWith("cx16.r")) {
                         val regStr = varName.lowercase().substring(5)
                         val reg = RegisterOrPair.valueOf(regStr.uppercase())
-                        AsmAssignSource(SourceStorageKind.REGISTER, program, asmgen, dt, register = reg)
+                        AsmAssignSource(SourceStorageKind.REGISTER, program, asmgen, value.type, register = reg)
                     } else {
-                        AsmAssignSource(SourceStorageKind.VARIABLE, program, asmgen, dt, variableAsmName = varName)
+                        AsmAssignSource(SourceStorageKind.VARIABLE, program, asmgen, value.type, variableAsmName = varName)
                     }
                 }
-                is DirectMemoryRead -> {
+                is PtMemoryByte -> {
                     AsmAssignSource(SourceStorageKind.MEMORY, program, asmgen, DataType.UBYTE, memory = value)
                 }
-                is ArrayIndexedExpression -> {
+                is PtArrayIndexer -> {
-                    val dt = value.inferType(program).getOrElse { throw AssemblyError("unknown dt") }
+                    AsmAssignSource(SourceStorageKind.ARRAY, program, asmgen, value.type, array = value)
-                    AsmAssignSource(SourceStorageKind.ARRAY, program, asmgen, dt, array = value)
                 }
-                is BuiltinFunctionCall -> {
+                is PtBuiltinFunctionCall -> {
-                    val returnType = value.inferType(program)
+                    AsmAssignSource(SourceStorageKind.EXPRESSION, program, asmgen, value.type, expression = value)
-                    AsmAssignSource(SourceStorageKind.EXPRESSION, program, asmgen, returnType.getOrElse { throw AssemblyError("unknown dt") }, expression = value)
                 }
-                is FunctionCallExpression -> {
+                is PtFunctionCall -> {
-                    val sub = value.target.targetSubroutine(program)!!
+                    val symbol = asmgen.symbolTable.lookup(value.name) ?: throw AssemblyError("lookup error ${value.name}")
-                    val returnType = sub.returntypes.zip(sub.asmReturnvaluesRegisters).firstOrNull { rr -> rr.second.registerOrPair != null || rr.second.statusflag!=null }?.first
+                    val sub = symbol.astNode as IPtSubroutine
+                    val returnType = 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 -> {
-                    val returnType = value.inferType(program)
+                    AsmAssignSource(SourceStorageKind.EXPRESSION, program, asmgen, value.type, expression = value)
-                    AsmAssignSource(SourceStorageKind.EXPRESSION, program, asmgen, returnType.getOrElse { throw AssemblyError("unknown dt") }, expression = value)
                 }
             }
         }
@@ -199,17 +209,27 @@ internal class AsmAssignSource(val kind: SourceStorageKind,
 }
 
 
-internal class AsmAssignment(val source: AsmAssignSource,
+internal sealed class AsmAssignmentBase(val source: AsmAssignSource,
-                             val target: AsmAssignTarget,
+                                        val target: AsmAssignTarget,
-                             val isAugmentable: Boolean,
+                                        val memsizer: IMemSizer,
-                             memsizer: IMemSizer,
+                                        val position: Position) {
-                             val position: Position) {
-
     init {
         if(target.register !in arrayOf(RegisterOrPair.XY, RegisterOrPair.AX, RegisterOrPair.AY))
             require(source.datatype != DataType.UNDEFINED) { "must not be placeholder/undefined datatype at $position" }
             require(memsizer.memorySize(source.datatype) <= memsizer.memorySize(target.datatype)) {
-                "source dt size must be less or equal to target dt size at $position"
+                "source dt size must be less or equal to target dt size at $position srcdt=${source.datatype} targetdt=${target.datatype}"
             }
     }
 }
+
+internal class AsmAssignment(source: AsmAssignSource,
+                             target: AsmAssignTarget,
+                             memsizer: IMemSizer,
+                             position: Position): AsmAssignmentBase(source, target, memsizer, position)
+
+internal class AsmAugmentedAssignment(source: AsmAssignSource,
+                                      val operator: String,
+                                      target: AsmAssignTarget,
+                                      memsizer: IMemSizer,
+                                      position: Position): AsmAssignmentBase(source, target, memsizer, position)
+

codeGenCpu6502/test/Dummies.kt

@@ -0,0 +1,78 @@
+package prog8tests.codegencpu6502
+
+import prog8.code.core.*
+
+
+internal object DummyMemsizer : IMemSizer {
+    override fun memorySize(dt: DataType) = when(dt) {
+        in ByteDatatypes -> 1
+        DataType.FLOAT -> 5
+        else -> 2
+    }
+    override fun memorySize(arrayDt: DataType, numElements: Int) = when(arrayDt) {
+        DataType.ARRAY_UW -> numElements*2
+        DataType.ARRAY_W -> numElements*2
+        DataType.ARRAY_F -> numElements*5
+        else -> numElements
+    }
+}
+
+internal object DummyStringEncoder : IStringEncoding {
+    override val defaultEncoding: Encoding = Encoding.ISO
+
+    override fun encodeString(str: String, encoding: Encoding): List<UByte> {
+        return emptyList()
+    }
+
+    override fun decodeString(bytes: Iterable<UByte>, encoding: Encoding): String {
+        return ""
+    }
+}
+
+internal class ErrorReporterForTests(private val throwExceptionAtReportIfErrors: Boolean=true, private val keepMessagesAfterReporting: Boolean=false): IErrorReporter {
+
+    val errors = mutableListOf<String>()
+    val warnings = mutableListOf<String>()
+    val infos = mutableListOf<String>()
+
+    override fun err(msg: String, position: Position) {
+        val text = "${position.toClickableStr()} $msg"
+        if(text !in errors)
+            errors.add(text)
+    }
+
+    override fun warn(msg: String, position: Position) {
+        val text = "${position.toClickableStr()} $msg"
+        if(text !in warnings)
+            warnings.add(text)
+    }
+
+    override fun info(msg: String, position: Position) {
+        val text = "${position.toClickableStr()} $msg"
+        if(text !in infos)
+            infos.add(text)
+    }
+
+    override fun undefined(symbol: List<String>, position: Position) {
+        err("undefined symbol: ${symbol.joinToString(".")}", position)
+    }
+
+    override fun noErrors(): Boolean  = errors.isEmpty()
+
+    override fun report() {
+        infos.forEach { println("UNITTEST COMPILATION REPORT: INFO: $it") }
+        warnings.forEach { println("UNITTEST COMPILATION REPORT: WARNING: $it") }
+        errors.forEach { println("UNITTEST COMPILATION REPORT: ERROR: $it") }
+        if(throwExceptionAtReportIfErrors)
+            finalizeNumErrors(errors.size, warnings.size, infos.size)
+        if(!keepMessagesAfterReporting) {
+            clear()
+        }
+    }
+
+    fun clear() {
+        errors.clear()
+        warnings.clear()
+        infos.clear()
+    }
+}

codeGenCpu6502/test/TestCodegen.kt

@@ -0,0 +1,129 @@
+package prog8tests.codegencpu6502
+
+import io.kotest.assertions.throwables.shouldNotThrowAny
+import io.kotest.assertions.withClue
+import io.kotest.core.spec.style.FunSpec
+import io.kotest.matchers.ints.shouldBeGreaterThanOrEqual
+import io.kotest.matchers.shouldBe
+import prog8.code.SymbolTableMaker
+import prog8.code.ast.*
+import prog8.code.core.*
+import prog8.code.target.C64Target
+import prog8.codegen.cpu6502.AsmGen6502
+import java.nio.file.Files
+import kotlin.io.path.Path
+
+class TestCodegen: FunSpec({
+
+    fun getTestOptions(): CompilationOptions {
+        val target = C64Target()
+        return CompilationOptions(
+            OutputType.RAW,
+            CbmPrgLauncherType.NONE,
+            ZeropageType.DONTUSE,
+            zpReserved = emptyList(),
+            zpAllowed = CompilationOptions.AllZeropageAllowed,
+            floats = true,
+            noSysInit = false,
+            compTarget = target,
+            loadAddress = target.machine.PROGRAM_LOAD_ADDRESS
+        )
+    }
+
+    test("augmented assign on arrays") {
+//main {
+//    sub start() {
+//        ubyte[] particleX = [1,2,3]
+//        ubyte[] particleDX = [1,2,3]
+//        particleX[2] += particleDX[2]
+//
+//        word @shared xx = 1
+//        xx = -xx
+//        xx += 42
+//        xx += cx16.r0
+//    }
+//}
+        val codegen = AsmGen6502(prefixSymbols = false)
+        val program = PtProgram("test", DummyMemsizer, DummyStringEncoder)
+        val block = PtBlock("main",false, SourceCode.Generated("test"), PtBlock.Options(), Position.DUMMY)
+        val sub = PtSub("start", emptyList(), null, Position.DUMMY)
+        sub.add(PtVariable("pi", DataType.UBYTE, ZeropageWish.DONTCARE, PtNumber(DataType.UBYTE, 0.0, Position.DUMMY), null, Position.DUMMY))
+        sub.add(PtVariable("particleX", DataType.ARRAY_UB, ZeropageWish.DONTCARE, null, 3u, Position.DUMMY))
+        sub.add(PtVariable("particleDX", DataType.ARRAY_UB, ZeropageWish.DONTCARE, null, 3u, Position.DUMMY))
+        sub.add(PtVariable("xx", DataType.WORD, ZeropageWish.DONTCARE, PtNumber(DataType.WORD, 1.0, Position.DUMMY), null, Position.DUMMY))
+
+        val assign = PtAugmentedAssign("+=", Position.DUMMY)
+        val target = PtAssignTarget(Position.DUMMY).also {
+            val targetIdx = PtArrayIndexer(DataType.UBYTE, Position.DUMMY).also { idx ->
+                idx.add(PtIdentifier("main.start.particleX", DataType.ARRAY_UB, Position.DUMMY))
+                idx.add(PtNumber(DataType.UBYTE, 2.0, Position.DUMMY))
+            }
+            it.add(targetIdx)
+        }
+        val value = PtArrayIndexer(DataType.UBYTE, Position.DUMMY)
+        value.add(PtIdentifier("main.start.particleDX", DataType.ARRAY_UB, Position.DUMMY))
+        value.add(PtNumber(DataType.UBYTE, 2.0, Position.DUMMY))
+        assign.add(target)
+        assign.add(value)
+        sub.add(assign)
+
+        val prefixAssign = PtAugmentedAssign("-", Position.DUMMY)
+        val prefixTarget = PtAssignTarget(Position.DUMMY).also {
+            it.add(PtIdentifier("main.start.xx", DataType.WORD, Position.DUMMY))
+        }
+        prefixAssign.add(prefixTarget)
+        prefixAssign.add(PtIdentifier("main.start.xx", DataType.WORD, Position.DUMMY))
+        sub.add(prefixAssign)
+
+        val numberAssign = PtAugmentedAssign("-=", Position.DUMMY)
+        val numberAssignTarget = PtAssignTarget(Position.DUMMY).also {
+            it.add(PtIdentifier("main.start.xx", DataType.WORD, Position.DUMMY))
+        }
+        numberAssign.add(numberAssignTarget)
+        numberAssign.add(PtNumber(DataType.WORD, 42.0, Position.DUMMY))
+        sub.add(numberAssign)
+
+        val cxregAssign = PtAugmentedAssign("+=", Position.DUMMY)
+        val cxregAssignTarget = PtAssignTarget(Position.DUMMY).also {
+            it.add(PtIdentifier("main.start.xx", DataType.WORD, Position.DUMMY))
+        }
+        cxregAssign.add(cxregAssignTarget)
+        cxregAssign.add(PtIdentifier("cx16.r0", DataType.UWORD, Position.DUMMY))
+        sub.add(cxregAssign)
+
+        block.add(sub)
+        program.add(block)
+
+        // define the "cx16.r0" virtual register
+        val cx16block = PtBlock("cx16", false, SourceCode.Generated("test"), PtBlock.Options(), Position.DUMMY)
+        cx16block.add(PtMemMapped("r0", DataType.UWORD, 100u, null, Position.DUMMY))
+        program.add(cx16block)
+
+        val options = getTestOptions()
+        val st = SymbolTableMaker(program, options).make()
+        val errors = ErrorReporterForTests()
+        val result = codegen.generate(program, st, options, errors)!!
+        result.name shouldBe "test"
+        Files.deleteIfExists(Path("${result.name}.asm"))
+    }
+
+    test("64tass assembler available? - if this fails you need to install 64tass version 1.58 or newer in the path") {
+        val command = mutableListOf("64tass", "--version")
+        shouldNotThrowAny {
+            val proc = ProcessBuilder(command).start()
+            val output = String(proc.inputStream.readBytes())
+            val result = proc.waitFor()
+            result.shouldBe(0)
+            val (_, version) = output.split('V')
+            val (major, minor, _) = version.split('.')
+            val majorNum = major.toInt()
+            val minorNum = minor.toInt()
+            withClue("64tass version should be 1.58 or newer") {
+                majorNum shouldBeGreaterThanOrEqual 1
+                if (majorNum == 1)
+                    minorNum shouldBeGreaterThanOrEqual 58
+            }
+        }
+    }
+})
+

codeGenExperimental/build.gradle

@@ -29,17 +29,17 @@ dependencies {
     implementation project(':codeGenIntermediate')
     implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8"
     // implementation "org.jetbrains.kotlin:kotlin-reflect"
-    implementation "com.michael-bull.kotlin-result:kotlin-result-jvm:1.1.16"
+    implementation "com.michael-bull.kotlin-result:kotlin-result-jvm:1.1.18"
 
 }
 
 sourceSets {
     main {
         java {
-            srcDirs = ["${project.projectDir}/src"]
+            srcDir "${project.projectDir}/src"
         }
         resources {
-            srcDirs = ["${project.projectDir}/res"]
+            srcDir "${project.projectDir}/res"
         }
     }
 }

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

@@ -3,18 +3,19 @@ package prog8.codegen.experimental
 import prog8.code.SymbolTable
 import prog8.code.ast.PtProgram
 import prog8.code.core.CompilationOptions
-import prog8.code.core.IAssemblyGenerator
 import prog8.code.core.IAssemblyProgram
+import prog8.code.core.ICodeGeneratorBackend
 import prog8.code.core.IErrorReporter
 import prog8.codegen.intermediate.IRCodeGen
 import prog8.intermediate.IRFileWriter
 
-class CodeGen(private val program: PtProgram,
+class ExperiCodeGen: ICodeGeneratorBackend {
-              private val symbolTable: SymbolTable,
+    override fun generate(
-              private val options: CompilationOptions,
+        program: PtProgram,
-              private val errors: IErrorReporter
+        symbolTable: SymbolTable,
-): IAssemblyGenerator {
+        options: CompilationOptions,
-    override fun compileToAssembly(): IAssemblyProgram? {
+        errors: IErrorReporter
+    ): IAssemblyProgram {
 
         // you could write a code generator directly on the PtProgram AST,
         // but you can also use the Intermediate Representation to build a codegen on:
@@ -25,6 +26,15 @@ class CodeGen(private val program: PtProgram,
         IRFileWriter(irProgram, null).write()
 
         println("** experimental codegen stub: no assembly generated **")
-        return null
+        return EmptyProgram
     }
-}
+}
+
+private object EmptyProgram : IAssemblyProgram {
+    override val name = "<Empty Program>"
+    override fun assemble(options: CompilationOptions, errors: IErrorReporter): Boolean {
+        println("** nothing assembled **")
+        return true
+    }
+
+}

codeGenIntermediate/build.gradle

@@ -28,18 +28,18 @@ dependencies {
     implementation project(':intermediate')
     implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8"
     // implementation "org.jetbrains.kotlin:kotlin-reflect"
-    implementation "com.michael-bull.kotlin-result:kotlin-result-jvm:1.1.16"
+    implementation "com.michael-bull.kotlin-result:kotlin-result-jvm:1.1.18"
 
-    testImplementation 'io.kotest:kotest-runner-junit5-jvm:5.3.2'
+    testImplementation 'io.kotest:kotest-runner-junit5-jvm:5.8.0'
 }
 
 sourceSets {
     main {
         java {
-            srcDirs = ["${project.projectDir}/src"]
+            srcDir "${project.projectDir}/src"
         }
         resources {
-            srcDirs = ["${project.projectDir}/res"]
+            srcDir "${project.projectDir}/res"
         }
     }
     test {

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

@@ -3,6 +3,7 @@ package prog8.codegen.intermediate
 import prog8.code.ast.*
 import prog8.code.core.AssemblyError
 import prog8.code.core.DataType
+import prog8.code.core.PrefixOperators
 import prog8.code.core.SignedDatatypes
 import prog8.intermediate.*
 
@@ -12,148 +13,132 @@ internal class AssignmentGen(private val codeGen: IRCodeGen, private val express
         if(assignment.target.children.single() is PtMachineRegister)
             throw AssemblyError("assigning to a register should be done by just evaluating the expression into resultregister")
 
-        return if (assignment.isInplaceAssign)
+        val chunks = translateRegularAssign(assignment)
-            translateInplaceAssign(assignment)
+        chunks.filterIsInstance<IRCodeChunk>().firstOrNull()?.appendSrcPosition(assignment.position)
-        else
+        return chunks
-            translateRegularAssign(assignment)
     }
 
-    private fun translateInplaceAssign(assignment: PtAssignment): IRCodeChunks {
+    internal fun translate(augAssign: PtAugmentedAssign): IRCodeChunks {
-        val ident = assignment.target.identifier
+        if(augAssign.target.children.single() is PtMachineRegister)
-        val memory = assignment.target.memory
+            throw AssemblyError("assigning to a register should be done by just evaluating the expression into resultregister")
-        val array = assignment.target.array
 
-        return if(ident!=null) {
+        val ident = augAssign.target.identifier
-            assignSelfInMemory(ident.targetName.joinToString("."), assignment.value, assignment)
+        val memory = augAssign.target.memory
+        val array = augAssign.target.array
+
+        val chunks = if(ident!=null) {
+            assignVarAugmented(ident.name, augAssign)
         } else if(memory != null) {
             if(memory.address is PtNumber)
-                assignSelfInMemoryKnownAddress((memory.address as PtNumber).number.toInt(), assignment.value, assignment)
+                assignMemoryAugmented((memory.address as PtNumber).number.toInt(), augAssign)
             else
-                fallbackAssign(assignment)
+                fallbackAssign(augAssign)
         } else if(array!=null) {
             // NOTE: naive fallback assignment here will sometimes generate code that loads the index value multiple times
             // in a register. It's way too much work to optimize that here - instead, we trust that the generated IL assembly
             // will be optimized later and have the double assignments removed.
-            fallbackAssign(assignment)
+            fallbackAssign(augAssign)
         } else {
-            fallbackAssign(assignment)
+            fallbackAssign(augAssign)
         }
+        chunks.filterIsInstance<IRCodeChunk>().firstOrNull()?.appendSrcPosition(augAssign.position)
+        return chunks
     }
 
-    private fun assignSelfInMemoryKnownAddress(
+    private fun assignMemoryAugmented(
         address: Int,
-        value: PtExpression,
+        assignment: PtAugmentedAssign
-        origAssign: PtAssignment
     ): IRCodeChunks {
-        val vmDt = codeGen.irType(value.type)
+        val value = assignment.value
-        when(value) {
+        val targetDt = irType(assignment.target.type)
-            is PtIdentifier -> return emptyList() // do nothing, x=x null assignment.
+        val signed = assignment.target.type in SignedDatatypes
-            is PtMachineRegister -> return emptyList() // do nothing, reg=reg null assignment
+        return when(assignment.operator) {
-            is PtPrefix -> return inplacePrefix(value.operator, vmDt, address, null)
+            "+=" -> expressionEval.operatorPlusInplace(address, null, targetDt, value)
-            is PtBinaryExpression -> return inplaceBinexpr(value.operator, value.right, vmDt, value.type in SignedDatatypes, address, null, origAssign)
+            "-=" -> expressionEval.operatorMinusInplace(address, null, targetDt, value)
-            is PtMemoryByte -> {
+            "*=" -> expressionEval.operatorMultiplyInplace(address, null, targetDt, value)
-                return if (!codeGen.options.compTarget.machine.isIOAddress(address.toUInt()))
+            "/=" -> expressionEval.operatorDivideInplace(address, null, targetDt, signed, value)
-                    emptyList() // do nothing, mem=mem null assignment.
+            "|=" -> expressionEval.operatorOrInplace(address, null, targetDt, value)
-                else {
+            "&=" -> expressionEval.operatorAndInplace(address, null, targetDt, value)
-                    // read and write a (i/o) memory location to itself.
+            "^=" -> expressionEval.operatorXorInplace(address, null, targetDt, value)
-                    val tempReg = codeGen.registers.nextFree()
+            "<<=" -> expressionEval.operatorShiftLeftInplace(address, null, targetDt, value)
-                    val code = IRCodeChunk(null, null)
+            ">>=" -> expressionEval.operatorShiftRightInplace(address, null, targetDt, signed, value)
-                    code += IRInstruction(Opcode.LOADM, vmDt, reg1 = tempReg, value = address)
+            "%=" -> expressionEval.operatorModuloInplace(address, null, targetDt, value)
-                    code += IRInstruction(Opcode.STOREM, vmDt, reg1 = tempReg, value = address)
+            "==" -> expressionEval.operatorEqualsInplace(address, null, targetDt, value)
-                    listOf(code)
+            "!=" -> expressionEval.operatorNotEqualsInplace(address, null, targetDt, value)
-                }
+            "<" -> expressionEval.operatorLessInplace(address, null, targetDt, signed, value)
-            }
+            ">" -> expressionEval.operatorGreaterInplace(address, null, targetDt, signed, value)
-            else -> return fallbackAssign(origAssign)
+            "<=" -> expressionEval.operatorLessEqualInplace(address, null, targetDt, signed, value)
+            ">=" -> expressionEval.operatorGreaterEqualInplace(address, null, targetDt, signed, value)
+            in PrefixOperators -> inplacePrefix(assignment.operator, targetDt, address, null)
+
+            else -> throw AssemblyError("invalid augmented assign operator ${assignment.operator}")
         }
     }
 
-    private fun assignSelfInMemory(
+    private fun assignVarAugmented(symbol: String, assignment: PtAugmentedAssign): IRCodeChunks {
-        symbol: String,
+        val value = assignment.value
-        value: PtExpression,
+        val signed = assignment.target.type in SignedDatatypes
-        origAssign: PtAssignment
+        val targetDt = irType(assignment.target.type)
-    ): IRCodeChunks {
+        return when(assignment.operator) {
-        val vmDt = codeGen.irType(value.type)
+            "+=" -> expressionEval.operatorPlusInplace(null, symbol, targetDt, value)
-        return when(value) {
+            "-=" -> expressionEval.operatorMinusInplace(null, symbol, targetDt, value)
-            is PtIdentifier -> emptyList() // do nothing, x=x null assignment.
+            "*=" -> expressionEval.operatorMultiplyInplace(null, symbol, targetDt, value)
-            is PtMachineRegister -> emptyList() // do nothing, reg=reg null assignment
+            "/=" -> expressionEval.operatorDivideInplace(null, symbol, targetDt, signed, value)
-            is PtPrefix -> inplacePrefix(value.operator, vmDt, null, symbol)
+            "|=" -> expressionEval.operatorOrInplace(null, symbol, targetDt, value)
-            is PtBinaryExpression -> inplaceBinexpr(value.operator, value.right, vmDt, value.type in SignedDatatypes, null, symbol, origAssign)
+            "or=" -> expressionEval.operatorLogicalOrInplace(null, symbol, targetDt, value)
-            is PtMemoryByte -> {
+            "&=" -> expressionEval.operatorAndInplace(null, symbol, targetDt, value)
-                val code = IRCodeChunk(null, null)
+            "and=" -> expressionEval.operatorLogicalAndInplace(null, symbol, targetDt, value)
-                val tempReg = codeGen.registers.nextFree()
+            "^=", "xor=" -> expressionEval.operatorXorInplace(null, symbol, targetDt, value)
-                code += IRInstruction(Opcode.LOADM, vmDt, reg1 = tempReg, labelSymbol = symbol)
+            "<<=" -> expressionEval.operatorShiftLeftInplace(null, symbol, targetDt, value)
-                code += IRInstruction(Opcode.STOREM, vmDt, reg1 = tempReg, labelSymbol = symbol)
+            ">>=" -> expressionEval.operatorShiftRightInplace(null, symbol, targetDt, signed, value)
-                listOf(code)
+            "%=" -> expressionEval.operatorModuloInplace(null, symbol, targetDt, value)
-            }
+            "==" -> expressionEval.operatorEqualsInplace(null, symbol, targetDt, value)
-
+            "!=" -> expressionEval.operatorNotEqualsInplace(null, symbol, targetDt, value)
-            else -> fallbackAssign(origAssign)
+            "<" -> expressionEval.operatorLessInplace(null, symbol, targetDt, signed, value)
+            ">" -> expressionEval.operatorGreaterInplace(null, symbol, targetDt, signed, value)
+            "<=" -> expressionEval.operatorLessEqualInplace(null, symbol, targetDt, signed, value)
+            ">=" -> expressionEval.operatorGreaterEqualInplace(null, symbol, targetDt, signed, value)
+            in PrefixOperators -> inplacePrefix(assignment.operator, targetDt, null, symbol)
+            else -> throw AssemblyError("invalid augmented assign operator ${assignment.operator}")
         }
     }
 
-    private fun fallbackAssign(origAssign: PtAssignment): IRCodeChunks {
+    private fun fallbackAssign(origAssign: PtAugmentedAssign): IRCodeChunks {
-        if (codeGen.options.slowCodegenWarnings)
+        val value: PtExpression
-            codeGen.errors.warn("indirect code for in-place assignment", origAssign.position)
+        if(origAssign.operator in PrefixOperators) {
-        return translateRegularAssign(origAssign)
+            value = PtPrefix(origAssign.operator, origAssign.target.type, origAssign.value.position)
-    }
+            value.add(origAssign.value)
-
-    private fun inplaceBinexpr(
-        operator: String,
-        operand: PtExpression,
-        vmDt: IRDataType,
-        signed: Boolean,
-        knownAddress: Int?,
-        symbol: String?,
-        origAssign: PtAssignment
-    ): IRCodeChunks {
-        if(knownAddress!=null) {
-            when (operator) {
-                "+" -> return expressionEval.operatorPlusInplace(knownAddress, null, vmDt, operand)
-                "-" -> return expressionEval.operatorMinusInplace(knownAddress, null, vmDt, operand)
-                "*" -> return expressionEval.operatorMultiplyInplace(knownAddress, null, vmDt, operand)
-                "/" -> return expressionEval.operatorDivideInplace(knownAddress, null, vmDt, signed, operand)
-                "|" -> return expressionEval.operatorOrInplace(knownAddress, null, vmDt, operand)
-                "&" -> return expressionEval.operatorAndInplace(knownAddress, null, vmDt, operand)
-                "^" -> return expressionEval.operatorXorInplace(knownAddress, null, vmDt, operand)
-                "<<" -> return expressionEval.operatorShiftLeftInplace(knownAddress, null, vmDt, operand)
-                ">>" -> return expressionEval.operatorShiftRightInplace(knownAddress, null, vmDt, signed, operand)
-                else -> {}
-            }
         } else {
-            symbol!!
+            require(origAssign.operator.endsWith('='))
-            when (operator) {
+            value = PtBinaryExpression(origAssign.operator.dropLast(1), origAssign.target.type, origAssign.value.position)
-                "+" -> return expressionEval.operatorPlusInplace(null, symbol, vmDt, operand)
+            val left: PtExpression = origAssign.target.children.single() as PtExpression
-                "-" -> return expressionEval.operatorMinusInplace(null, symbol, vmDt, operand)
+            value.add(left)
-                "*" -> return expressionEval.operatorMultiplyInplace(null, symbol, vmDt, operand)
+            value.add(origAssign.value)
-                "/" -> return expressionEval.operatorDivideInplace(null, symbol, vmDt, signed, operand)
-                "|" -> return expressionEval.operatorOrInplace(null, symbol, vmDt, operand)
-                "&" -> return expressionEval.operatorAndInplace(null, symbol, vmDt, operand)
-                "^" -> return expressionEval.operatorXorInplace(null, symbol, vmDt, operand)
-                "<<" -> return expressionEval.operatorShiftLeftInplace(null, symbol, vmDt, operand)
-                ">>" -> return expressionEval.operatorShiftRightInplace(null, symbol, vmDt, signed, operand)
-                else -> {}
-            }
         }
-        return fallbackAssign(origAssign)
+        val normalAssign = PtAssignment(origAssign.position)
+        normalAssign.add(origAssign.target)
+        normalAssign.add(value)
+        return translateRegularAssign(normalAssign)
     }
 
-    private fun inplacePrefix(operator: String, vmDt: IRDataType, knownAddress: Int?, addressSymbol: String?): IRCodeChunks {
+    private fun inplacePrefix(operator: String, vmDt: IRDataType, address: Int?, symbol: String?): IRCodeChunks {
         val code= IRCodeChunk(null, null)
         when(operator) {
             "+" -> { }
             "-" -> {
-                code += if(knownAddress!=null)
+                code += if(address!=null)
-                    IRInstruction(Opcode.NEGM, vmDt, value = knownAddress)
+                    IRInstruction(Opcode.NEGM, vmDt, address = address)
                 else
-                    IRInstruction(Opcode.NEGM, vmDt, labelSymbol = addressSymbol)
+                    IRInstruction(Opcode.NEGM, vmDt, labelSymbol = symbol)
             }
             "~" -> {
                 val regMask = codeGen.registers.nextFree()
                 val mask = if(vmDt==IRDataType.BYTE) 0x00ff else 0xffff
-                code += IRInstruction(Opcode.LOAD, vmDt, reg1=regMask, value = mask)
+                code += IRInstruction(Opcode.LOAD, vmDt, reg1=regMask, immediate = mask)
-                code += if(knownAddress!=null)
+                code += if(address!=null)
-                    IRInstruction(Opcode.XORM, vmDt, reg1=regMask, value = knownAddress)
+                    IRInstruction(Opcode.XORM, vmDt, reg1=regMask, address = address)
                 else
-                    IRInstruction(Opcode.XORM, vmDt, reg1=regMask, labelSymbol = addressSymbol)
+                    IRInstruction(Opcode.XORM, vmDt, reg1=regMask, labelSymbol = symbol)
             }
             else -> throw AssemblyError("weird prefix operator")
         }
@@ -162,120 +147,176 @@ internal class AssignmentGen(private val codeGen: IRCodeGen, private val express
 
     private fun translateRegularAssign(assignment: PtAssignment): IRCodeChunks {
         // note: assigning array and string values is done via an explicit memcopy/stringcopy function call.
-        val ident = assignment.target.identifier
+        val targetIdent = assignment.target.identifier
-        val memory = assignment.target.memory
+        val targetMemory = assignment.target.memory
-        val array = assignment.target.array
+        val targetArray = assignment.target.array
-        val vmDt = codeGen.irType(assignment.value.type)
+        val valueDt = irType(assignment.value.type)
+        val targetDt = irType(assignment.target.type)
         val result = mutableListOf<IRCodeChunkBase>()
-        var resultRegister = -1
+
-        var resultFpRegister = -1
+        var valueRegister = -1
+        var valueFpRegister = -1
         val zero = codeGen.isZero(assignment.value)
         if(!zero) {
             // calculate the assignment value
-            if (vmDt == IRDataType.FLOAT) {
+            if (valueDt == IRDataType.FLOAT) {
-                resultFpRegister = codeGen.registers.nextFreeFloat()
+                val tr = expressionEval.translateExpression(assignment.value)
-                result += expressionEval.translateExpression(assignment.value, -1, resultFpRegister)
+                valueFpRegister = tr.resultFpReg
+                addToResult(result, tr, -1, valueFpRegister)
             } else {
-                resultRegister = if (assignment.value is PtMachineRegister) {
+                val extendByteToWord = if(targetDt != valueDt) {
-                    (assignment.value as PtMachineRegister).register
+                    // usually an error EXCEPT when a byte is assigned to a word.
+                    if(targetDt==IRDataType.WORD && valueDt==IRDataType.BYTE)
+                        true
+                    else
+                        throw AssemblyError("assignment value and target dt mismatch")
+                } else false
+                if (assignment.value is PtMachineRegister) {
+                    valueRegister = (assignment.value as PtMachineRegister).register
+                    if(extendByteToWord) {
+                        valueRegister = codeGen.registers.nextFree()
+                        addInstr(result, IRInstruction(Opcode.EXT, IRDataType.BYTE, reg1=valueRegister, reg2=(assignment.value as PtMachineRegister).register), null)
+                    }
                 } else {
-                    val reg = codeGen.registers.nextFree()
+                    val tr = expressionEval.translateExpression(assignment.value)
-                    result += expressionEval.translateExpression(assignment.value, reg, -1)
+                    valueRegister = tr.resultReg
-                    reg
+                    addToResult(result, tr, valueRegister, -1)
+                    if(extendByteToWord) {
+                        valueRegister = codeGen.registers.nextFree()
+                        val opcode = if(assignment.value.type in SignedDatatypes) Opcode.EXTS else Opcode.EXT
+                        addInstr(result, IRInstruction(opcode, IRDataType.BYTE, reg1=valueRegister, reg2=tr.resultReg), null)
+                    }
                 }
             }
         }
-        if(ident!=null) {
+
-            val symbol = ident.targetName.joinToString(".")
+        if(targetIdent!=null) {
             val instruction = if(zero) {
-                IRInstruction(Opcode.STOREZM, vmDt, labelSymbol = symbol)
+                IRInstruction(Opcode.STOREZM, targetDt, labelSymbol = targetIdent.name)
             } else {
-                if (vmDt == IRDataType.FLOAT)
+                if (targetDt == IRDataType.FLOAT)
-                    IRInstruction(Opcode.STOREM, vmDt, fpReg1 = resultFpRegister, labelSymbol = symbol)
+                    IRInstruction(Opcode.STOREM, targetDt, fpReg1 = valueFpRegister, labelSymbol = targetIdent.name)
                 else
-                    IRInstruction(Opcode.STOREM, vmDt, reg1 = resultRegister, labelSymbol = symbol)
+                    IRInstruction(Opcode.STOREM, targetDt, reg1 = valueRegister, labelSymbol = targetIdent.name)
             }
             result += IRCodeChunk(null, null).also { it += instruction }
             return result
         }
-        else if(array!=null) {
+        else if(targetArray!=null) {
-            val variable = array.variable.targetName.joinToString(".")
+            val variable = targetArray.variable.name
-            val itemsize = codeGen.program.memsizer.memorySize(array.type)
+            val itemsize = codeGen.program.memsizer.memorySize(targetArray.type)
 
-            if(array.variable.type==DataType.UWORD) {
+            if(targetArray.usesPointerVariable) {
-                // indexing a pointer var instead of a real array or string
                 if(itemsize!=1)
                     throw AssemblyError("non-array var indexing requires bytes dt")
-                if(array.index.type!=DataType.UBYTE)
+                if(targetArray.index.type!=DataType.UBYTE)
                     throw AssemblyError("non-array var indexing requires bytes index")
-                val idxReg = codeGen.registers.nextFree()
+                val tr = expressionEval.translateExpression(targetArray.index)
-                result += expressionEval.translateExpression(array.index, idxReg, -1)
+                val idxReg = tr.resultReg
+                addToResult(result, tr, tr.resultReg, -1)
                 val code = IRCodeChunk(null, null)
                 if(zero) {
                     // there's no STOREZIX instruction
-                    resultRegister = codeGen.registers.nextFree()
+                    valueRegister = codeGen.registers.nextFree()
-                    code += IRInstruction(Opcode.LOAD, vmDt, reg1=resultRegister, value=0)
+                    code += IRInstruction(Opcode.LOAD, targetDt, reg1=valueRegister, immediate = 0)
                 }
-                code += IRInstruction(Opcode.STOREIX, vmDt, reg1=resultRegister, reg2=idxReg, labelSymbol = variable)
+                code += IRInstruction(Opcode.STOREIX, targetDt, reg1=valueRegister, reg2=idxReg, labelSymbol = variable)
                 result += code
                 return result
             }
 
-            val fixedIndex = constIntValue(array.index)
+            val fixedIndex = constIntValue(targetArray.index)
+            val arrayLength = codeGen.symbolTable.getLength(targetArray.variable.name)
             if(zero) {
                 if(fixedIndex!=null) {
-                    val offset = fixedIndex*itemsize
+                    val chunk = IRCodeChunk(null, null).also {
-                    val chunk = IRCodeChunk(null, null).also { it += IRInstruction(Opcode.STOREZM, vmDt, labelSymbol = "$variable+$offset") }
+                        if(targetArray.splitWords) {
+                            it += IRInstruction(Opcode.STOREZM, IRDataType.BYTE, immediate = arrayLength, labelSymbol = "${variable}_lsb", symbolOffset = fixedIndex)
+                            it += IRInstruction(Opcode.STOREZM, IRDataType.BYTE, immediate = arrayLength, labelSymbol = "${variable}_msb", symbolOffset = fixedIndex)
+                        }
+                        else
+                            it += IRInstruction(Opcode.STOREZM, targetDt, labelSymbol = variable, symbolOffset = fixedIndex*itemsize)
+                    }
                     result += chunk
                 } else {
-                    val indexReg = codeGen.registers.nextFree()
+                    val (code, indexReg) = loadIndexReg(targetArray, itemsize)
-                    result += loadIndexReg(array, itemsize, indexReg)
+                    result += code
-                    result += IRCodeChunk(null, null).also { it += IRInstruction(Opcode.STOREZX, vmDt, reg1=indexReg, labelSymbol = variable) }
+                    result += IRCodeChunk(null, null).also {
+                        if(targetArray.splitWords) {
+                            it += IRInstruction(Opcode.STOREZX, IRDataType.BYTE, reg1 = indexReg, immediate = arrayLength, labelSymbol = variable+"_lsb")
+                            it += IRInstruction(Opcode.STOREZX, IRDataType.BYTE, reg1 = indexReg, immediate = arrayLength, labelSymbol = variable+"_msb")
+                        }
+                        else
+                            it += IRInstruction(Opcode.STOREZX, targetDt, reg1=indexReg, labelSymbol = variable)
+                    }
                 }
             } else {
-                if(vmDt== IRDataType.FLOAT) {
+                if(targetDt== IRDataType.FLOAT) {
                     if(fixedIndex!=null) {
                         val offset = fixedIndex*itemsize
-                        val chunk = IRCodeChunk(null, null).also { it += IRInstruction(Opcode.STOREM, vmDt, fpReg1 = resultFpRegister, labelSymbol = "$variable+$offset") }
+                        val chunk = IRCodeChunk(null, null).also {
+                            it += IRInstruction(Opcode.STOREM, targetDt, fpReg1 = valueFpRegister, labelSymbol = variable, symbolOffset = offset)
+                        }
                         result += chunk
                     } else {
-                        val indexReg = codeGen.registers.nextFree()
+                        val (code, indexReg) = loadIndexReg(targetArray, itemsize)
-                        result += loadIndexReg(array, itemsize, indexReg)
+                        result += code
-                        result += IRCodeChunk(null, null).also { it += IRInstruction(Opcode.STOREX, vmDt, reg1 = indexReg, fpReg1 = resultFpRegister, labelSymbol = variable) }
+                        result += IRCodeChunk(null, null).also {
+                            it += IRInstruction(Opcode.STOREX, targetDt, reg1 = indexReg, fpReg1 = valueFpRegister, labelSymbol = variable)
+                        }
                     }
                 } else {
                     if(fixedIndex!=null) {
-                        val offset = fixedIndex*itemsize
+                        val chunk = IRCodeChunk(null, null).also {
-                        val chunk = IRCodeChunk(null, null).also { it += IRInstruction(Opcode.STOREM, vmDt, reg1 = resultRegister, labelSymbol = "$variable+$offset") }
+                            if(targetArray.splitWords) {
+                                val msbReg = codeGen.registers.nextFree()
+                                it += IRInstruction(Opcode.STOREM, IRDataType.BYTE, reg1 = valueRegister, immediate = arrayLength, labelSymbol = "${variable}_lsb", symbolOffset = fixedIndex)
+                                it += IRInstruction(Opcode.MSIG, IRDataType.BYTE, reg1 = msbReg, reg2 = valueRegister)
+                                it += IRInstruction(Opcode.STOREM, IRDataType.BYTE, reg1 = msbReg, immediate = arrayLength, labelSymbol = "${variable}_msb", symbolOffset = fixedIndex)
+                            }
+                            else
+                                it += IRInstruction(Opcode.STOREM, targetDt, reg1 = valueRegister, labelSymbol = variable, symbolOffset = fixedIndex*itemsize)
+                        }
                         result += chunk
                     } else {
-                        val indexReg = codeGen.registers.nextFree()
+                        val (code, indexReg) = loadIndexReg(targetArray, itemsize)
-                        result += loadIndexReg(array, itemsize, indexReg)
+                        result += code
-                        result += IRCodeChunk(null, null).also { it += IRInstruction(Opcode.STOREX, vmDt, reg1 = resultRegister, reg2=indexReg, labelSymbol = variable) }
+                        result += IRCodeChunk(null, null).also {
+                            if(targetArray.splitWords) {
+                                val msbReg = codeGen.registers.nextFree()
+                                it += IRInstruction(Opcode.STOREX, IRDataType.BYTE, reg1 = valueRegister, reg2=indexReg, immediate = arrayLength, labelSymbol = "${variable}_lsb")
+                                it += IRInstruction(Opcode.MSIG, IRDataType.BYTE, reg1 = msbReg, reg2 = valueRegister)
+                                it += IRInstruction(Opcode.STOREX, IRDataType.BYTE, reg1 = msbReg, reg2=indexReg, immediate = arrayLength, labelSymbol = "${variable}_msb")
+                            }
+                            else
+                                it += IRInstruction(Opcode.STOREX, targetDt, reg1 = valueRegister, reg2=indexReg, labelSymbol = variable)
+                        }
                     }
                 }
             }
             return result
         }
-        else if(memory!=null) {
+        else if(targetMemory!=null) {
-            require(vmDt== IRDataType.BYTE) { "must be byte type ${memory.position}"}
+            require(targetDt == IRDataType.BYTE) { "must be byte type ${targetMemory.position}"}
             if(zero) {
-                if(memory.address is PtNumber) {
+                if(targetMemory.address is PtNumber) {
-                    val chunk = IRCodeChunk(null, null).also { it += IRInstruction(Opcode.STOREZM, vmDt, value=(memory.address as PtNumber).number.toInt()) }
+                    val chunk = IRCodeChunk(null, null).also { it += IRInstruction(Opcode.STOREZM, targetDt, address = (targetMemory.address as PtNumber).number.toInt()) }
                     result += chunk
                 } else {
-                    val addressReg = codeGen.registers.nextFree()
+                    val tr = expressionEval.translateExpression(targetMemory.address)
-                    result += expressionEval.translateExpression(memory.address, addressReg, -1)
+                    val addressReg = tr.resultReg
-                    result += IRCodeChunk(null, null).also { it += IRInstruction(Opcode.STOREZI, vmDt, reg1=addressReg) }
+                    addToResult(result, tr, tr.resultReg, -1)
+                    result += IRCodeChunk(null, null).also { it += IRInstruction(Opcode.STOREZI, targetDt, reg1=addressReg) }
                 }
             } else {
-                if(memory.address is PtNumber) {
+                if(targetMemory.address is PtNumber) {
-                    val chunk = IRCodeChunk(null, null).also { it += IRInstruction(Opcode.STOREM, vmDt, reg1=resultRegister, value=(memory.address as PtNumber).number.toInt()) }
+                    val chunk = IRCodeChunk(null, null).also { it += IRInstruction(Opcode.STOREM, targetDt, reg1=valueRegister, address=(targetMemory.address as PtNumber).number.toInt()) }
                     result += chunk
                 } else {
-                    val addressReg = codeGen.registers.nextFree()
+                    val tr = expressionEval.translateExpression(targetMemory.address)
-                    result += expressionEval.translateExpression(memory.address, addressReg, -1)
+                    val addressReg = tr.resultReg
-                    result += IRCodeChunk(null, null).also { it += IRInstruction(Opcode.STOREI, vmDt, reg1=resultRegister, reg2=addressReg) }
+                    addToResult(result, tr, tr.resultReg, -1)
+                    result += IRCodeChunk(null, null).also { it += IRInstruction(Opcode.STOREI, targetDt, reg1=valueRegister, reg2=addressReg) }
                 }
             }
 
@@ -285,14 +326,22 @@ internal class AssignmentGen(private val codeGen: IRCodeGen, private val express
             throw AssemblyError("weird assigntarget")
     }
 
-    private fun loadIndexReg(array: PtArrayIndexer, itemsize: Int, indexReg: Int): IRCodeChunks {
+    private fun loadIndexReg(array: PtArrayIndexer, itemsize: Int): Pair<IRCodeChunks, Int> {
-        return if(itemsize==1) {
+        // returns the code to load the Index into the register, which is also returned.
-            expressionEval.translateExpression(array.index, indexReg, -1)
+
-        } else {
+        val result = mutableListOf<IRCodeChunkBase>()
-            val mult = PtBinaryExpression("*", DataType.UBYTE, array.position)
+        if(itemsize==1 || array.splitWords) {
-            mult.children += array.index
+            val tr = expressionEval.translateExpression(array.index)
-            mult.children += PtNumber(DataType.UBYTE, itemsize.toDouble(), array.position)
+            addToResult(result, tr, tr.resultReg, -1)
-            expressionEval.translateExpression(mult, indexReg, -1)
+            return Pair(result, tr.resultReg)
         }
+
+        val mult: PtExpression
+        mult = PtBinaryExpression("*", DataType.UBYTE, array.position)
+        mult.children += array.index
+        mult.children += PtNumber(DataType.UBYTE, itemsize.toDouble(), array.position)
+        val tr = expressionEval.translateExpression(mult)
+        addToResult(result, tr, tr.resultReg, -1)
+        return Pair(result, tr.resultReg)
     }
 }

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

@@ -1,12 +1,42 @@
 package prog8.codegen.intermediate
 
+import prog8.code.core.IErrorReporter
 import prog8.intermediate.*
 
-internal class IRPeepholeOptimizer(private val irprog: IRProgram) {
+class IRPeepholeOptimizer(private val irprog: IRProgram) {
-    fun optimize() {
+    fun optimize(optimizationsEnabled: Boolean, errors: IErrorReporter) {
-        irprog.blocks.asSequence().flatMap { it.children.filterIsInstance<IRSubroutine>() }.forEach { sub ->
+        if(!optimizationsEnabled)
+            return optimizeOnlyJoinChunks()
+
+        peepholeOptimize()
+        val remover = IRUnusedCodeRemover(irprog, errors)
+        var totalRemovals = 0
+        do {
+            val numRemoved = remover.optimize()
+            totalRemovals += numRemoved
+        } while(numRemoved>0 && errors.noErrors())
+        errors.report()
+
+        if(totalRemovals>0) {
+            irprog.linkChunks()  // re-link again.
+        }
+    }
+
+    private fun optimizeOnlyJoinChunks() {
+        irprog.foreachSub { sub ->
+            joinChunks(sub)
             removeEmptyChunks(sub)
             joinChunks(sub)
+        }
+        irprog.linkChunks() // re-link
+    }
+
+    private fun peepholeOptimize() {
+        irprog.foreachSub { sub ->
+            joinChunks(sub)
+            removeEmptyChunks(sub)
+            joinChunks(sub)
+
             sub.chunks.withIndex().forEach { (index, chunk1) ->
                 // we don't optimize Inline Asm chunks here.
                 val chunk2 = if(index<sub.chunks.size-1) sub.chunks[index+1] else null
@@ -15,20 +45,39 @@ internal class IRPeepholeOptimizer(private val irprog: IRProgram) {
                         val indexedInstructions = chunk1.instructions.withIndex()
                             .map { IndexedValue(it.index, it.value) }
                         val changed = removeNops(chunk1, indexedInstructions)
-                                || removeDoubleLoadsAndStores(chunk1, indexedInstructions)       // TODO not yet implemented
+                                || replaceConcatZeroMsbWithExt(chunk1, indexedInstructions)
+                                || removeDoubleLoadsAndStores(chunk1, indexedInstructions)
                                 || removeUselessArithmetic(chunk1, indexedInstructions)
+                                || removeNeedlessCompares(chunk1, indexedInstructions)
                                 || removeWeirdBranches(chunk1, chunk2, indexedInstructions)
                                 || removeDoubleSecClc(chunk1, indexedInstructions)
                                 || cleanupPushPop(chunk1, indexedInstructions)
-                        // TODO other optimizations:
+                        // TODO other optimizations
-                        //  more complex optimizations such as unused registers
                     } while (changed)
                 }
             }
             removeEmptyChunks(sub)
         }
 
-        irprog.linkChunks() // re-link
+        // TODO also do register optimization step here at the end?
+
+        irprog.linkChunks()  // re-link
+    }
+
+    private fun replaceConcatZeroMsbWithExt(chunk: IRCodeChunk, indexedInstructions: List<IndexedValue<IRInstruction>>): Boolean {
+        var changed = false
+        indexedInstructions.reversed().forEach { (idx, ins) ->
+            if (ins.opcode == Opcode.CONCAT) {
+                // if the previous instruction loads a zero in the msb, this can be turned into EXT.B instead
+                val prev = indexedInstructions[idx-1].value
+                if(prev.opcode==Opcode.LOAD && prev.immediate==0 && prev.reg1==ins.reg2) {
+                    chunk.instructions[idx] = IRInstruction(Opcode.EXT, IRDataType.BYTE, reg1 = ins.reg1, reg2 = ins.reg3)
+                    chunk.instructions.removeAt(idx-1)
+                    changed = true
+                }
+            }
+        }
+        return changed
     }
 
     private fun removeEmptyChunks(sub: IRSubroutine) {
@@ -38,7 +87,7 @@ internal class IRPeepholeOptimizer(private val irprog: IRProgram) {
         /*
         Empty Code chunk with label ->
             If next chunk has no label -> move label to next chunk, remove original
-            If next chunk has label -> label name should be the same, remove original. Otherwise FOR NOW leave it in place. (TODO: consolidate labels into 1)
+            If next chunk has label -> label name should be the same, remove original. Otherwise merge both labels into 1.
             If is last chunk -> keep chunk in place because of the label.
         Empty Code chunk without label ->
             should not have been generated! ERROR.
@@ -47,6 +96,7 @@ internal class IRPeepholeOptimizer(private val irprog: IRProgram) {
 
         val relabelChunks = mutableListOf<Pair<Int, String>>()
         val removeChunks = mutableListOf<Int>()
+        val replaceLabels = mutableMapOf<String, String>()
 
         sub.chunks.withIndex().forEach { (index, chunk) ->
             if(chunk is IRCodeChunk && chunk.instructions.isEmpty()) {
@@ -60,10 +110,18 @@ internal class IRPeepholeOptimizer(private val irprog: IRProgram) {
                             relabelChunks += Pair(index + 1, chunk.label!!)
                             removeChunks += index
                         } else {
-                            if (chunk.label == nextchunk.label)
+                            // merge both labels into 1 except if this is the label chunk at the start of the subroutine
-                                removeChunks += index
+                            if(index>0) {
-                            else {
+                                if (chunk.label == nextchunk.label)
-                                // TODO: consolidate labels on same chunk
+                                    removeChunks += index
+                                else {
+                                    removeChunks += index
+                                    replaceLabels[chunk.label!!] = nextchunk.label!!
+                                    replaceLabels.entries.forEach { (key, value) ->
+                                        if (value == chunk.label)
+                                            replaceLabels[key] = nextchunk.label!!
+                                    }
+                                }
                             }
                         }
                     }
@@ -73,10 +131,32 @@ internal class IRPeepholeOptimizer(private val irprog: IRProgram) {
 
         relabelChunks.forEach { (index, label) ->
             val chunk = IRCodeChunk(label, null)
-            chunk.instructions += sub.chunks[index].instructions
+            val subChunk = sub.chunks[index]
+            chunk.instructions += subChunk.instructions
+            if(subChunk is IRCodeChunk)
+                chunk.appendSrcPositions(subChunk.sourceLinesPositions)
             sub.chunks[index] = chunk
         }
         removeChunks.reversed().forEach { index -> sub.chunks.removeAt(index) }
+
+        sub.chunks.forEach { chunk ->
+            chunk.instructions.withIndex().forEach { (idx, instr) ->
+                instr.labelSymbol?.let {
+                    if(instr.opcode in OpcodesThatBranch) {
+                        replaceLabels.forEach { (from, to) ->
+                            if (it == from) {
+                                chunk.instructions[idx] = instr.copy(labelSymbol = to)
+                            }
+                            else {
+                                val actualPrefix = "$from."
+                                if (it.startsWith(actualPrefix))
+                                    chunk.instructions[idx] = instr.copy(labelSymbol = "$to.")
+                            }
+                        }
+                    }
+                }
+            }
+        }
     }
 
     private fun joinChunks(sub: IRSubroutine) {
@@ -85,7 +165,7 @@ internal class IRPeepholeOptimizer(private val irprog: IRProgram) {
         if(sub.chunks.isEmpty())
             return
 
-        fun mayJoin(previous: IRCodeChunkBase, chunk: IRCodeChunkBase): Boolean {
+        fun mayJoinCodeChunks(previous: IRCodeChunkBase, chunk: IRCodeChunkBase): Boolean {
             if(chunk.label!=null)
                 return false
             if(previous is IRCodeChunk && chunk is IRCodeChunk) {
@@ -102,12 +182,41 @@ internal class IRPeepholeOptimizer(private val irprog: IRProgram) {
         chunks += sub.chunks[0]
         for(ix in 1 until sub.chunks.size) {
             val lastChunk = chunks.last()
-            if(mayJoin(lastChunk, sub.chunks[ix])) {
+            val candidate = sub.chunks[ix]
-                lastChunk.instructions += sub.chunks[ix].instructions
+            when(candidate) {
-                lastChunk.next = sub.chunks[ix].next
+                is IRCodeChunk -> {
+                    if(mayJoinCodeChunks(lastChunk, candidate)) {
+                        lastChunk.instructions += candidate.instructions
+                        lastChunk.next = candidate.next
+                        if(lastChunk is IRCodeChunk)
+                            lastChunk.appendSrcPositions(candidate.sourceLinesPositions)
+                    }
+                    else
+                        chunks += candidate
+                }
+                is IRInlineAsmChunk -> {
+                    if(candidate.label!=null)
+                        chunks += candidate
+                    else if(lastChunk.isEmpty()) {
+                        val label = lastChunk.label
+                        if(label!=null)
+                            chunks += IRInlineAsmChunk(label, candidate.assembly, candidate.isIR, candidate.next)
+                        else
+                            chunks += candidate
+                    }
+                }
+                is IRInlineBinaryChunk -> {
+                    if(candidate.label!=null)
+                        chunks += candidate
+                    else if(lastChunk.isEmpty()) {
+                        val label = lastChunk.label
+                        if(label!=null)
+                            chunks += IRInlineBinaryChunk(label, candidate.data, candidate.next)
+                        else
+                            chunks += candidate
+                    }
+                }
             }
-            else
-                chunks += sub.chunks[ix]
         }
         sub.chunks.clear()
         sub.chunks += chunks
@@ -119,8 +228,8 @@ internal class IRPeepholeOptimizer(private val irprog: IRProgram) {
         indexedInstructions.reversed().forEach { (idx, ins) ->
             if(ins.opcode== Opcode.PUSH) {
                 if(idx < chunk.instructions.size-1) {
-                    val insAfter = chunk.instructions[idx+1] as? IRInstruction
+                    val insAfter = chunk.instructions[idx+1]
-                    if(insAfter!=null && insAfter.opcode == Opcode.POP) {
+                    if(insAfter.opcode == Opcode.POP) {
                         if(ins.reg1==insAfter.reg1) {
                             chunk.instructions.removeAt(idx)
                             chunk.instructions.removeAt(idx)
@@ -143,16 +252,16 @@ internal class IRPeepholeOptimizer(private val irprog: IRProgram) {
         indexedInstructions.reversed().forEach { (idx, ins) ->
             if(ins.opcode== Opcode.SEC || ins.opcode== Opcode.CLC) {
                 if(idx < chunk.instructions.size-1) {
-                    val insAfter = chunk.instructions[idx+1] as? IRInstruction
+                    val insAfter = chunk.instructions[idx+1]
-                    if(insAfter?.opcode == ins.opcode) {
+                    if(insAfter.opcode == ins.opcode) {
                         chunk.instructions.removeAt(idx)
                         changed = true
                     }
-                    else if(ins.opcode== Opcode.SEC && insAfter?.opcode== Opcode.CLC) {
+                    else if(ins.opcode== Opcode.SEC && insAfter.opcode== Opcode.CLC) {
                         chunk.instructions.removeAt(idx)
                         changed = true
                     }
-                    else if(ins.opcode== Opcode.CLC && insAfter?.opcode== Opcode.SEC) {
+                    else if(ins.opcode== Opcode.CLC && insAfter.opcode== Opcode.SEC) {
                         chunk.instructions.removeAt(idx)
                         changed = true
                     }
@@ -174,14 +283,60 @@ internal class IRPeepholeOptimizer(private val irprog: IRProgram) {
                     changed = true
                 }
             }
+
             // remove useless RETURN
-            if(ins.opcode == Opcode.RETURN && idx>0) {
+            if(idx>0 && (ins.opcode == Opcode.RETURN || ins.opcode==Opcode.RETURNR)) {
-                val previous = chunk.instructions[idx-1] as? IRInstruction
+                val previous = chunk.instructions[idx-1]
-                if(previous?.opcode in OpcodesThatJump) {
+                if(previous.opcode in OpcodesThatJump) {
                     chunk.instructions.removeAt(idx)
                     changed = true
                 }
             }
+
+            // replace subsequent opcodes that jump by just the first
+            if(idx>0 && (ins.opcode in OpcodesThatJump)) {
+                val previous = chunk.instructions[idx-1]
+                if(previous.opcode in OpcodesThatJump) {
+                    chunk.instructions.removeAt(idx)
+                    changed = true
+                }
+            }
+
+            // replace call + return --> jump
+            // This can no longer be done here on the IR level, with the current CALL opcode that encodes the full subroutine call setup.
+            // If machine code is ever generated from this IR, *that* should possibly optimize the JSR + RTS into a JMP.
+//            if(idx>0 && ins.opcode==Opcode.RETURN) {
+//                val previous = chunk.instructions[idx-1]
+//                if(previous.opcode==Opcode.CALL) {
+//                    chunk.instructions[idx-1] = IRInstruction(Opcode.JUMP, address = previous.address, labelSymbol = previous.labelSymbol, branchTarget = previous.branchTarget)
+//                    chunk.instructions.removeAt(idx)
+//                    changed = true
+//                }
+//            }
+        }
+        return changed
+    }
+
+    private fun removeNeedlessCompares(chunk: IRCodeChunk, indexedInstructions: List<IndexedValue<IRInstruction>>): Boolean {
+        // a CMPI with 0, after an instruction like LOAD that already sets the status bits, can be removed.
+        // but only if the instruction after it is not using the Carry bit because that won't be set by a LOAD instruction etc.
+        var changed = false
+        indexedInstructions.reversed().forEach { (idx, ins) ->
+            if(idx>0 && idx<(indexedInstructions.size-1) && ins.opcode==Opcode.CMPI && ins.immediate==0) {
+                val previous = indexedInstructions[idx-1].value
+                if(previous.reg1==ins.reg1) {
+                    if (previous.opcode in OpcodesThatSetStatusbitsIncludingCarry) {
+                        chunk.instructions.removeAt(idx)
+                        changed = true
+                    } else if (previous.opcode in OpcodesThatSetStatusbitsButNotCarry) {
+                        val next = indexedInstructions[idx + 1].value
+                        if (next.opcode !in OpcodesThatDependOnCarry) {
+                            chunk.instructions.removeAt(idx)
+                            changed = true
+                        }
+                    }
+                }
+            }
         }
         return changed
     }
@@ -192,47 +347,47 @@ internal class IRPeepholeOptimizer(private val irprog: IRProgram) {
         indexedInstructions.reversed().forEach { (idx, ins) ->
             when (ins.opcode) {
                 Opcode.DIV, Opcode.DIVS, Opcode.MUL, Opcode.MOD -> {
-                    if (ins.value == 1) {
+                    if (ins.immediate == 1) {
                         chunk.instructions.removeAt(idx)
                         changed = true
                     }
                 }
                 Opcode.ADD, Opcode.SUB -> {
-                    if (ins.value == 1) {
+                    if (ins.immediate == 1) {
                         chunk.instructions[idx] = IRInstruction(
                             if (ins.opcode == Opcode.ADD) Opcode.INC else Opcode.DEC,
                             ins.type,
                             ins.reg1
                         )
                         changed = true
-                    } else if (ins.value == 0) {
+                    } else if (ins.immediate == 0) {
                         chunk.instructions.removeAt(idx)
                         changed = true
                     }
                 }
                 Opcode.AND -> {
-                    if (ins.value == 0) {
+                    if (ins.immediate == 0) {
-                        chunk.instructions[idx] = IRInstruction(Opcode.LOAD, ins.type, reg1 = ins.reg1, value = 0)
+                        chunk.instructions[idx] = IRInstruction(Opcode.LOAD, ins.type, reg1 = ins.reg1, immediate = 0)
                         changed = true
-                    } else if (ins.value == 255 && ins.type == IRDataType.BYTE) {
+                    } else if (ins.immediate == 255 && ins.type == IRDataType.BYTE) {
                         chunk.instructions.removeAt(idx)
                         changed = true
-                    } else if (ins.value == 65535 && ins.type == IRDataType.WORD) {
+                    } else if (ins.immediate == 65535 && ins.type == IRDataType.WORD) {
                         chunk.instructions.removeAt(idx)
                         changed = true
                     }
                 }
                 Opcode.OR -> {
-                    if (ins.value == 0) {
+                    if (ins.immediate == 0) {
                         chunk.instructions.removeAt(idx)
                         changed = true
-                    } else if ((ins.value == 255 && ins.type == IRDataType.BYTE) || (ins.value == 65535 && ins.type == IRDataType.WORD)) {
+                    } else if ((ins.immediate == 255 && ins.type == IRDataType.BYTE) || (ins.immediate == 65535 && ins.type == IRDataType.WORD)) {
-                        chunk.instructions[idx] = IRInstruction(Opcode.LOAD, ins.type, reg1 = ins.reg1, value = ins.value)
+                        chunk.instructions[idx] = IRInstruction(Opcode.LOAD, ins.type, reg1 = ins.reg1, immediate = ins.immediate)
                         changed = true
                     }
                 }
                 Opcode.XOR -> {
-                    if (ins.value == 0) {
+                    if (ins.immediate == 0) {
                         chunk.instructions.removeAt(idx)
                         changed = true
                     }
@@ -255,18 +410,21 @@ internal class IRPeepholeOptimizer(private val irprog: IRProgram) {
     }
 
     private fun removeDoubleLoadsAndStores(chunk: IRCodeChunk, indexedInstructions: List<IndexedValue<IRInstruction>>): Boolean {
+        return false
+
+/*
         var changed = false
         indexedInstructions.forEach { (idx, ins) ->
 
             // TODO: detect multiple loads to the same target registers, only keep first (if source is not I/O memory)
             // TODO: detect multiple stores to the same target, only keep first (if target is not I/O memory)
             // TODO: detect multiple float ffrom/fto to the same target, only keep first
-            // TODO: detect multiple sequential rnd with same reg1, only keep one
             // TODO: detect subsequent same xors/nots/negs, remove the pairs completely as they cancel out
             // TODO: detect multiple same ands, ors; only keep first
             // TODO: (hard) detect multiple registers being assigned the same value (and not changed) - use only 1 of them
             // ...
         }
         return changed
+*/
     }
 }

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

@@ -0,0 +1,103 @@
+package prog8.codegen.intermediate
+
+import prog8.intermediate.IRProgram
+
+
+class IRRegisterOptimizer(private val irProg: IRProgram) {
+    fun optimize() {
+        // reuseRegisters()
+    }
+
+/*
+    TODO: this register re-use renumbering isn't going to work like this,
+    because subroutines will be clobbering the registers that the subroutine
+    which is calling them might be using...
+
+
+    private fun reuseRegisters() {
+
+        fun addToUsage(usage: MutableMap<Pair<Int, IRDataType>, MutableSet<IRCodeChunkBase>>,
+                       regnum: Int,
+                       dt: IRDataType,
+                       chunk: IRCodeChunkBase) {
+            val key = regnum to dt
+            val chunks = usage[key] ?: mutableSetOf()
+            chunks.add(chunk)
+            usage[key] = chunks
+        }
+
+        val usage: MutableMap<Pair<Int, IRDataType>, MutableSet<IRCodeChunkBase>> = mutableMapOf()
+
+        irProg.foreachCodeChunk { chunk ->
+            chunk.usedRegisters().regsTypes.forEach { (regNum, types) ->
+                types.forEach { dt ->
+                    addToUsage(usage, regNum, dt, chunk)
+                }
+            }
+        }
+
+        val registerReplacements = usage.asSequence()
+            .filter { it.value.size==1 }
+            .map { it.key to it.value.iterator().next() }
+            .groupBy({ it.second }, {it.first})
+            .asSequence()
+            .associate { (chunk, registers) ->
+                chunk to registers.withIndex().associate { (index, reg) -> reg to 50000+index }
+            }
+
+        registerReplacements.forEach { replaceRegisters(it.key, it.value) }
+    }
+
+    private fun replaceRegisters(chunk: IRCodeChunkBase, replacements: Map<Pair<Int, IRDataType>, Int>) {
+        val (rF, rI) = replacements.asSequence().partition { it.key.second==IRDataType.FLOAT }
+        val replacementsInt = rI.associate { it.key.first to it.value }
+        val replacementsFloat = rF.associate { it.key.first to it.value }
+
+        fun replaceRegs(fcallArgs: FunctionCallArgs?): FunctionCallArgs? {
+            if(fcallArgs==null)
+                return null
+            val args = if(fcallArgs.arguments.isEmpty()) fcallArgs.arguments else {
+                fcallArgs.arguments.map {
+                    FunctionCallArgs.ArgumentSpec(
+                        it.name,
+                        it.address,
+                        FunctionCallArgs.RegSpec(
+                            it.reg.dt,
+                            if(it.reg.dt==IRDataType.FLOAT)
+                                replacementsFloat.getOrDefault(it.reg.registerNum, it.reg.registerNum)
+                            else
+                                replacementsInt.getOrDefault(it.reg.registerNum, it.reg.registerNum),
+                            it.reg.cpuRegister
+                        )
+                    )
+                }
+            }
+            val rt = fcallArgs.returns
+            val returns = if(rt==null) null else {
+                FunctionCallArgs.RegSpec(
+                    rt.dt,
+                    if(rt.dt==IRDataType.FLOAT)
+                        replacementsFloat.getOrDefault(rt.registerNum, rt.registerNum)
+                    else
+                        replacementsInt.getOrDefault(rt.registerNum, rt.registerNum),
+                    rt.cpuRegister
+                )
+            }
+            return FunctionCallArgs(args, returns)
+        }
+
+        fun replaceRegs(instruction: IRInstruction): IRInstruction {
+            val reg1 = replacementsInt.getOrDefault(instruction.reg1, instruction.reg1)
+            val reg2 = replacementsInt.getOrDefault(instruction.reg2, instruction.reg2)
+            val fpReg1 = replacementsFloat.getOrDefault(instruction.fpReg1, instruction.fpReg1)
+            val fpReg2 = replacementsFloat.getOrDefault(instruction.fpReg2, instruction.fpReg2)
+            return instruction.copy(reg1 = reg1, reg2 = reg2, fpReg1 = fpReg1, fpReg2 = fpReg2, fcallArgs = replaceRegs(instruction.fcallArgs))
+        }
+        val newInstructions = chunk.instructions.map {
+            replaceRegs(it)
+        }
+        chunk.instructions.clear()
+        chunk.instructions.addAll(newInstructions)
+    }
+*/
+}

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

@@ -1,38 +1,21 @@
 package prog8.codegen.intermediate
 
 import prog8.code.core.IErrorReporter
-import prog8.code.core.SourceCode.Companion.libraryFilePrefix
 import prog8.intermediate.*
 
 
-internal class IRUnusedCodeRemover(private val irprog: IRProgram, private val errors: IErrorReporter) {
+class IRUnusedCodeRemover(
+    private val irprog: IRProgram,
+    private val errors: IErrorReporter
+) {
     fun optimize(): Int {
-        val allLabeledChunks = mutableMapOf<String, IRCodeChunkBase>()
+        var numRemoved = removeUnusedSubroutines() + removeUnusedAsmSubroutines()
-
-        irprog.blocks.asSequence().flatMap { it.children.filterIsInstance<IRSubroutine>() }.forEach { sub ->
-            sub.chunks.forEach { chunk ->
-                chunk.label?.let { allLabeledChunks[it] = chunk }
-            }
-        }
-
-        var numRemoved = removeSimpleUnlinked(allLabeledChunks) + removeUnreachable(allLabeledChunks)
-
-        // remove empty subs
-        irprog.blocks.forEach { block ->
-            block.children.filterIsInstance<IRSubroutine>().reversed().forEach { sub ->
-                if(sub.isEmpty()) {
-                    if(!sub.position.file.startsWith(libraryFilePrefix))
-                        errors.warn("unused subroutine ${sub.label}", sub.position)
-                    block.children.remove(sub)
-                    numRemoved++
-                }
-            }
-        }
 
         // remove empty blocks
         irprog.blocks.reversed().forEach { block ->
             if(block.isEmpty()) {
                 irprog.blocks.remove(block)
+                pruneSymboltable(block.label)
                 numRemoved++
             }
         }
@@ -40,17 +23,157 @@ internal class IRUnusedCodeRemover(private val irprog: IRProgram, private val er
         return numRemoved
     }
 
+    private fun pruneSymboltable(blockLabel: String) {
+        // we could clean up the SymbolTable as well, but ONLY if these symbols aren't referenced somewhere still in an instruction or variable initializer value
+        val prefix = "$blockLabel."
+        val blockVars = irprog.st.allVariables().filter { it.name.startsWith(prefix) }
+        blockVars.forEach { stVar ->
+            irprog.allSubs().flatMap { it.chunks }.forEach { chunk ->
+                chunk.instructions.forEach { ins ->
+                    if(ins.labelSymbol == stVar.name) {
+                        return  // symbol occurs in an instruction
+                    }
+                }
+            }
+
+            irprog.st.allVariables().forEach { variable ->
+                val initValue = variable.onetimeInitializationArrayValue
+                if(!initValue.isNullOrEmpty()) {
+                    if(initValue.any {
+                        it.addressOfSymbol?.startsWith(blockLabel)==true
+                    })
+                        return   // symbol occurs in an initializer value (address-of this symbol)_
+                }
+            }
+        }
+
+        irprog.st.removeTree(blockLabel)
+    }
+
+    private fun removeUnusedSubroutines(): Int {
+        val allLabeledChunks = mutableMapOf<String, IRCodeChunkBase>()
+        irprog.foreachCodeChunk { chunk ->
+            chunk.label?.let { allLabeledChunks[it] = chunk }
+        }
+
+        var numRemoved = removeSimpleUnlinked(allLabeledChunks) + removeUnreachable(allLabeledChunks)
+        irprog.blocks.forEach { block ->
+            block.children.filterIsInstance<IRSubroutine>().reversed().forEach { sub ->
+                if(sub.isEmpty()) {
+                    if(!block.options.ignoreUnused) {
+                        errors.info("unused subroutine '${sub.label}'", sub.position)
+                    }
+                    block.children.remove(sub)
+                    irprog.st.removeTree(sub.label)
+                    numRemoved++
+                }
+            }
+        }
+
+        return numRemoved
+    }
+
+    private fun removeUnusedAsmSubroutines(): Int {
+        val allLabeledAsmsubs = irprog.blocks.asSequence().flatMap { it.children.filterIsInstance<IRAsmSubroutine>() }
+            .associateBy { it.label }
+
+        var numRemoved = removeSimpleUnlinkedAsmsubs(allLabeledAsmsubs)
+        irprog.blocks.forEach { block ->
+            block.children.filterIsInstance<IRAsmSubroutine>().reversed().forEach { sub ->
+                if(sub.isEmpty()) {
+                    if(!block.options.ignoreUnused) {
+                        errors.info("unused subroutine '${sub.label}'", sub.position)
+                    }
+                    block.children.remove(sub)
+                    irprog.st.removeTree(sub.label)
+                    numRemoved++
+                }
+            }
+        }
+
+        return numRemoved
+    }
+
+    private fun removeSimpleUnlinkedAsmsubs(allSubs: Map<String, IRAsmSubroutine>): Int {
+        val linkedAsmSubs = mutableSetOf<IRAsmSubroutine>()
+
+        // TODO: asmsubs in library modules are never removed, we can't really tell here if they're actually being called or not...
+
+        // check if asmsub is called from another asmsub
+        irprog.blocks.asSequence().forEach { block ->
+            block.children.filterIsInstance<IRAsmSubroutine>().forEach { sub ->
+                if (block.options.forceOutput || block.library)
+                    linkedAsmSubs += sub
+                if (sub.asmChunk.isNotEmpty()) {
+                    allSubs.forEach { (label, asmsub) ->
+                        if (sub.asmChunk.assembly.contains(label))
+                            linkedAsmSubs += asmsub
+                    }
+                }
+                val inlineAsm = sub.asmChunk.next as? IRInlineAsmChunk
+                if(inlineAsm!=null) {
+                    allSubs.forEach { (label, asmsub) ->
+                        if (inlineAsm.assembly.contains(label))
+                            linkedAsmSubs += asmsub
+                    }
+                }
+            }
+        }
+
+        // check if asmsub is linked or called from another regular subroutine
+        irprog.foreachCodeChunk { chunk ->
+            chunk.instructions.forEach {
+                it.labelSymbol?.let { label -> allSubs[label]?.let { cc -> linkedAsmSubs += cc } }
+                // note: branchTarget can't yet point to another IRAsmSubroutine, so do nothing when it's set
+            }
+        }
+
+        return removeUnlinkedAsmsubs(linkedAsmSubs)
+    }
+
+    private fun removeUnlinkedAsmsubs(linkedAsmSubs: Set<IRAsmSubroutine>): Int {
+        var numRemoved = 0
+        irprog.blocks.asSequence().forEach { block ->
+            block.children.withIndex().reversed().forEach { (index, child) ->
+                if(child is IRAsmSubroutine && child !in linkedAsmSubs) {
+                    block.children.removeAt(index)
+                    numRemoved++
+                }
+            }
+        }
+        return numRemoved
+    }
+
     private fun removeUnreachable(allLabeledChunks: MutableMap<String, IRCodeChunkBase>): Int {
-        val entrypointSub = irprog.blocks.single { it.name=="main" }.children.single { it is IRSubroutine && it.label=="main.start" }
+        val entrypointSub = irprog.blocks.single { it.label=="main" }
+            .children.single { it is IRSubroutine && it.label=="main.start" }
         val reachable = mutableSetOf((entrypointSub as IRSubroutine).chunks.first())
 
+        // all chunks referenced in array initializer values are also 'reachable':
+        irprog.st.allVariables()
+            .filter { !it.uninitialized }
+            .forEach {
+                it.onetimeInitializationArrayValue?.let { array ->
+                    array.forEach {elt ->
+                        if(elt.addressOfSymbol!=null && irprog.st.lookup(elt.addressOfSymbol!!)==null)
+                            reachable.add(irprog.getChunkWithLabel(elt.addressOfSymbol!!))
+                    }
+                }
+            }
+
         fun grow() {
             val new = mutableSetOf<IRCodeChunkBase>()
             reachable.forEach {
                 it.next?.let { next -> new += next }
                 it.instructions.forEach { instr ->
                     if (instr.branchTarget == null)
-                        instr.labelSymbol?.let { label -> allLabeledChunks[label]?.let { chunk -> new += chunk } }
+                        instr.labelSymbol?.let { label ->
+                            val chunk = allLabeledChunks[label.substringBeforeLast('.')]
+                            if(chunk!=null)
+                                new+=chunk
+                            else
+                                allLabeledChunks[label]?.let { new += it }
+                        }
                     else
                         new += instr.branchTarget!!
                 }
@@ -72,29 +195,47 @@ internal class IRUnusedCodeRemover(private val irprog: IRProgram, private val er
     private fun removeSimpleUnlinked(allLabeledChunks: Map<String, IRCodeChunkBase>): Int {
         val linkedChunks = mutableSetOf<IRCodeChunkBase>()
 
-        irprog.blocks.asSequence().flatMap { it.children.filterIsInstance<IRSubroutine>() }.forEach { sub ->
+        // all chunks referenced in array initializer values are linked as well!:
-            sub.chunks.forEach { chunk ->
+        irprog.st.allVariables()
-                chunk.next?.let { next -> linkedChunks += next }
+            .filter { !it.uninitialized }
-                chunk.instructions.forEach {
+            .forEach {
-                    if(it.branchTarget==null) {
+                it.onetimeInitializationArrayValue?.let { array ->
-                        it.labelSymbol?.let { label -> allLabeledChunks[label]?.let { cc -> linkedChunks += cc } }
+                    array.forEach {elt ->
-                    } else {
+                        if(elt.addressOfSymbol!=null && irprog.st.lookup(elt.addressOfSymbol!!)==null)
-                        linkedChunks += it.branchTarget!!
+                            linkedChunks += irprog.getChunkWithLabel(elt.addressOfSymbol!!)
                     }
                 }
-                if (chunk.label == "main.start")
+            }
-                    linkedChunks += chunk
+
+        irprog.foreachCodeChunk { chunk ->
+            chunk.next?.let { next -> linkedChunks += next }
+            chunk.instructions.forEach {
+                if(it.branchTarget==null) {
+                    it.labelSymbol?.let { label -> allLabeledChunks[label]?.let { cc -> linkedChunks += cc } }
+                } else {
+                    linkedChunks += it.branchTarget!!
+                }
+            }
+            if (chunk.label == "main.start")
+                linkedChunks += chunk
+        }
+
+        // make sure that chunks that are only used as a prefix of a label, are also marked as linked
+        linkedChunks.toList().forEach { chunk ->
+            chunk.instructions.forEach {
+                if(it.labelSymbol!=null) {
+                    val chunkName = it.labelSymbol!!.substringBeforeLast('.')
+                    allLabeledChunks[chunkName]?.let { linkedChunks+=it }
+                }
             }
         }
 
         return removeUnlinkedChunks(linkedChunks)
     }
 
-    private fun removeUnlinkedChunks(
+    private fun removeUnlinkedChunks(linkedChunks: Set<IRCodeChunkBase>): Int {
-        linkedChunks: MutableSet<IRCodeChunkBase>
-    ): Int {
         var numRemoved = 0
-        irprog.blocks.asSequence().flatMap { it.children.filterIsInstance<IRSubroutine>() }.forEach { sub ->
+        irprog.foreachSub { sub ->
             sub.chunks.withIndex().reversed().forEach { (index, chunk) ->
                 if (chunk !in linkedChunks) {
                     if (chunk === sub.chunks[0]) {

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

@@ -1,10 +1,7 @@
 package prog8.codegen.intermediate
 
-import prog8.code.core.AssemblyError
-import prog8.intermediate.SyscallRegisterBase
-
 internal class RegisterPool {
-    // reserve 0,1,2 for return values of subroutine calls and syscalls
+    // reserve 0,1,2 for return values of subroutine calls and syscalls in IR assembly code
     private var firstFree: Int=3
     private var firstFreeFloat: Int=3
 
@@ -14,16 +11,12 @@ internal class RegisterPool {
     fun nextFree(): Int {
         val result = firstFree
         firstFree++
-        if(firstFree >= SyscallRegisterBase)
-            throw AssemblyError("out of virtual registers (int)")
         return result
     }
 
     fun nextFreeFloat(): Int {
         val result = firstFreeFloat
         firstFreeFloat++
-        if(firstFreeFloat >= SyscallRegisterBase)
-            throw AssemblyError("out of virtual registers (fp)")
         return result
     }
 }

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

@@ -3,31 +3,30 @@ package prog8.codegen.vm
 import prog8.code.SymbolTable
 import prog8.code.ast.PtProgram
 import prog8.code.core.CompilationOptions
-import prog8.code.core.IAssemblyGenerator
 import prog8.code.core.IAssemblyProgram
+import prog8.code.core.ICodeGeneratorBackend
 import prog8.code.core.IErrorReporter
 import prog8.codegen.intermediate.IRCodeGen
 import prog8.intermediate.IRFileWriter
 import prog8.intermediate.IRProgram
 
-class VmCodeGen(private val program: PtProgram,
+class VmCodeGen: ICodeGeneratorBackend {
-                private val symbolTable: SymbolTable,
+    override fun generate(
-                private val options: CompilationOptions,
+        program: PtProgram,
-                private val errors: IErrorReporter
+        symbolTable: SymbolTable,
-): IAssemblyGenerator {
+        options: CompilationOptions,
-    override fun compileToAssembly(): IAssemblyProgram? {
+        errors: IErrorReporter
-
+    ): IAssemblyProgram {
         val irCodeGen = IRCodeGen(program, symbolTable, options, errors)
         val irProgram = irCodeGen.generate()
-
         return VmAssemblyProgram(irProgram.name, irProgram)
     }
 }
 
 
-internal class VmAssemblyProgram(override val name: String, private val irProgram: IRProgram): IAssemblyProgram {
+internal class VmAssemblyProgram(override val name: String, internal val irProgram: IRProgram): IAssemblyProgram {
 
-    override fun assemble(options: CompilationOptions): Boolean {
+    override fun assemble(options: CompilationOptions, errors: IErrorReporter): Boolean {
         // the VM reads the IR file from disk.
         IRFileWriter(irProgram, null).write()
         return true

codeGenIntermediate/test/Dummies.kt

@@ -1,20 +1,76 @@
-import prog8.code.core.DataType
+import prog8.code.core.*
-import prog8.code.core.Encoding
-import prog8.code.core.IMemSizer
-import prog8.code.core.IStringEncoding
 
 
 internal object DummyMemsizer : IMemSizer {
-    override fun memorySize(dt: DataType) = 0
+    override fun memorySize(dt: DataType) = when(dt) {
-    override fun memorySize(arrayDt: DataType, numElements: Int) = 0
+        in ByteDatatypes -> 1
+        DataType.FLOAT -> 5
+        else -> 2
+    }
+    override fun memorySize(arrayDt: DataType, numElements: Int) = when(arrayDt) {
+        DataType.ARRAY_UW -> numElements*2
+        DataType.ARRAY_W -> numElements*2
+        DataType.ARRAY_F -> numElements*5
+        else -> numElements
+    }
 }
 
 internal object DummyStringEncoder : IStringEncoding {
+    override val defaultEncoding: Encoding = Encoding.ISO
+
     override fun encodeString(str: String, encoding: Encoding): List<UByte> {
         return emptyList()
     }
 
-    override fun decodeString(bytes: List<UByte>, encoding: Encoding): String {
+    override fun decodeString(bytes: Iterable<UByte>, encoding: Encoding): String {
         return ""
     }
 }
+
+internal class ErrorReporterForTests(private val throwExceptionAtReportIfErrors: Boolean=true, private val keepMessagesAfterReporting: Boolean=false): IErrorReporter {
+
+    val errors = mutableListOf<String>()
+    val warnings = mutableListOf<String>()
+    val infos = mutableListOf<String>()
+
+    override fun err(msg: String, position: Position) {
+        val text = "${position.toClickableStr()} $msg"
+        if(text !in errors)
+            errors.add(text)
+    }
+
+    override fun warn(msg: String, position: Position) {
+        val text = "${position.toClickableStr()} $msg"
+        if(text !in warnings)
+            warnings.add(text)
+    }
+
+    override fun info(msg: String, position: Position) {
+        val text = "${position.toClickableStr()} $msg"
+        if(text !in infos)
+            infos.add(text)
+    }
+
+    override fun undefined(symbol: List<String>, position: Position) {
+        err("undefined symbol: ${symbol.joinToString(".")}", position)
+    }
+
+    override fun noErrors(): Boolean  = errors.isEmpty()
+
+    override fun report() {
+        infos.forEach { println("UNITTEST COMPILATION REPORT: INFO: $it") }
+        warnings.forEach { println("UNITTEST COMPILATION REPORT: WARNING: $it") }
+        errors.forEach { println("UNITTEST COMPILATION REPORT: ERROR: $it") }
+        if(throwExceptionAtReportIfErrors)
+            finalizeNumErrors(errors.size, warnings.size, infos.size)
+        if(!keepMessagesAfterReporting) {
+            clear()
+        }
+    }
+
+    fun clear() {
+        errors.clear()
+        warnings.clear()
+        infos.clear()
+    }
+}

codeGenIntermediate/test/TestIRPeepholeOpt.kt

@@ -8,7 +8,7 @@ import prog8.intermediate.*
 class TestIRPeepholeOpt: FunSpec({
     fun makeIRProgram(chunks: List<IRCodeChunkBase>): IRProgram {
         require(chunks.first().label=="main.start")
-        val block = IRBlock("main", null, IRBlock.BlockAlignment.NONE, Position.DUMMY)
+        val block = IRBlock("main", false, IRBlock.Options(), Position.DUMMY)
         val sub = IRSubroutine("main.start", emptyList(), null, Position.DUMMY)
         chunks.forEach { sub += it }
         block += sub
@@ -18,12 +18,13 @@ class TestIRPeepholeOpt: FunSpec({
             CbmPrgLauncherType.NONE,
             ZeropageType.DONTUSE,
             emptyList(),
+            CompilationOptions.AllZeropageAllowed,
             floats = false,
             noSysInit = true,
             compTarget = target,
             loadAddress = target.machine.PROGRAM_LOAD_ADDRESS
         )
-        val prog = IRProgram("test", IRSymbolTable(null), options, target)
+        val prog = IRProgram("test", IRSymbolTable(), options, target)
         prog.addBlock(block)
         prog.linkChunks()
         prog.validate()
@@ -36,25 +37,25 @@ class TestIRPeepholeOpt: FunSpec({
         return makeIRProgram(listOf(chunk))
     }
 
-    fun IRProgram.chunks(): List<IRCodeChunkBase> = this.blocks.flatMap { it.children.filterIsInstance<IRSubroutine>() }.flatMap { it.chunks }
+    fun IRProgram.chunks(): List<IRCodeChunkBase> = this.allSubs().flatMap { it.chunks }.toList()
 
     test("remove nops") {
         val irProg = makeIRProgram(listOf(
-            IRInstruction(Opcode.LOAD, IRDataType.BYTE, reg1=1, value=42),
+            IRInstruction(Opcode.LOAD, IRDataType.BYTE, reg1=1, immediate=42),
             IRInstruction(Opcode.NOP),
             IRInstruction(Opcode.NOP)
         ))
         irProg.chunks().single().instructions.size shouldBe 3
         val opt = IRPeepholeOptimizer(irProg)
-        opt.optimize()
+        opt.optimize(true, ErrorReporterForTests())
         irProg.chunks().single().instructions.size shouldBe 1
     }
 
     test("remove jmp to label below") {
         val c1 = IRCodeChunk("main.start", null)
-        c1 += IRInstruction(Opcode.JUMP, labelSymbol = "label")  // removed, but chunk stays because of label
+        c1 += IRInstruction(Opcode.JUMP, labelSymbol = "label")
         val c2 = IRCodeChunk("label", null)
-        c2 += IRInstruction(Opcode.JUMP, labelSymbol = "label2") // removed, but chunk stays because of label
+        c2 += IRInstruction(Opcode.JUMP, labelSymbol = "label2")
         c2 += IRInstruction(Opcode.NOP)  // removed
         val c3 = IRCodeChunk("label2", null)
         c3 += IRInstruction(Opcode.JUMP, labelSymbol = "label3")
@@ -65,16 +66,14 @@ class TestIRPeepholeOpt: FunSpec({
         irProg.chunks().size shouldBe 4
         irProg.chunks().flatMap { it.instructions }.size shouldBe 5
         val opt = IRPeepholeOptimizer(irProg)
-        opt.optimize()
+        opt.optimize(true, ErrorReporterForTests())
-        irProg.chunks().size shouldBe 4
+        irProg.chunks().size shouldBe 3
         irProg.chunks()[0].label shouldBe "main.start"
-        irProg.chunks()[1].label shouldBe "label"
+        irProg.chunks()[1].label shouldBe "label2"
-        irProg.chunks()[2].label shouldBe "label2"
+        irProg.chunks()[2].label shouldBe "label3"
-        irProg.chunks()[3].label shouldBe "label3"
         irProg.chunks()[0].isEmpty() shouldBe true
-        irProg.chunks()[1].isEmpty() shouldBe true
+        irProg.chunks()[1].isEmpty() shouldBe false
-        irProg.chunks()[2].isEmpty() shouldBe false
+        irProg.chunks()[2].isEmpty() shouldBe true
-        irProg.chunks()[3].isEmpty() shouldBe true
         val instr = irProg.chunks().flatMap { it.instructions }
         instr.size shouldBe 2
         instr[0].opcode shouldBe Opcode.JUMP
@@ -92,7 +91,7 @@ class TestIRPeepholeOpt: FunSpec({
         ))
         irProg.chunks().single().instructions.size shouldBe 6
         val opt = IRPeepholeOptimizer(irProg)
-        opt.optimize()
+        opt.optimize(true, ErrorReporterForTests())
         val instr = irProg.chunks().single().instructions
         instr.size shouldBe 1
         instr[0].opcode shouldBe Opcode.CLC
@@ -107,7 +106,7 @@ class TestIRPeepholeOpt: FunSpec({
         ))
         irProg.chunks().single().instructions.size shouldBe 4
         val opt = IRPeepholeOptimizer(irProg)
-        opt.optimize()
+        opt.optimize(true, ErrorReporterForTests())
         val instr = irProg.chunks().single().instructions
         instr.size shouldBe 1
         instr[0].opcode shouldBe Opcode.LOADR
@@ -117,31 +116,31 @@ class TestIRPeepholeOpt: FunSpec({
 
     test("remove useless div/mul, add/sub") {
         val irProg = makeIRProgram(listOf(
-            IRInstruction(Opcode.DIV, IRDataType.BYTE, reg1=42, value = 1),
+            IRInstruction(Opcode.DIV, IRDataType.BYTE, reg1=42, immediate = 1),
-            IRInstruction(Opcode.DIVS, IRDataType.BYTE, reg1=42, value = 1),
+            IRInstruction(Opcode.DIVS, IRDataType.BYTE, reg1=42, immediate = 1),
-            IRInstruction(Opcode.MUL, IRDataType.BYTE, reg1=42, value = 1),
+            IRInstruction(Opcode.MUL, IRDataType.BYTE, reg1=42, immediate = 1),
-            IRInstruction(Opcode.MOD, IRDataType.BYTE, reg1=42, value = 1),
+            IRInstruction(Opcode.MOD, IRDataType.BYTE, reg1=42, immediate = 1),
-            IRInstruction(Opcode.DIV, IRDataType.BYTE, reg1=42, value = 2),
+            IRInstruction(Opcode.DIV, IRDataType.BYTE, reg1=42, immediate = 2),
-            IRInstruction(Opcode.DIVS, IRDataType.BYTE, reg1=42, value = 2),
+            IRInstruction(Opcode.DIVS, IRDataType.BYTE, reg1=42, immediate = 2),
-            IRInstruction(Opcode.MUL, IRDataType.BYTE, reg1=42, value = 2),
+            IRInstruction(Opcode.MUL, IRDataType.BYTE, reg1=42, immediate = 2),
-            IRInstruction(Opcode.MOD, IRDataType.BYTE, reg1=42, value = 2),
+            IRInstruction(Opcode.MOD, IRDataType.BYTE, reg1=42, immediate = 2),
-            IRInstruction(Opcode.ADD, IRDataType.BYTE, reg1=42, value = 0),
+            IRInstruction(Opcode.ADD, IRDataType.BYTE, reg1=42, immediate = 0),
-            IRInstruction(Opcode.SUB, IRDataType.BYTE, reg1=42, value = 0)
+            IRInstruction(Opcode.SUB, IRDataType.BYTE, reg1=42, immediate = 0)
         ))
         irProg.chunks().single().instructions.size shouldBe 10
         val opt = IRPeepholeOptimizer(irProg)
-        opt.optimize()
+        opt.optimize(true, ErrorReporterForTests())
         irProg.chunks().single().instructions.size shouldBe 4
     }
 
     test("replace add/sub 1 by inc/dec") {
         val irProg = makeIRProgram(listOf(
-            IRInstruction(Opcode.ADD, IRDataType.BYTE, reg1=42, value = 1),
+            IRInstruction(Opcode.ADD, IRDataType.BYTE, reg1=42, immediate = 1),
-            IRInstruction(Opcode.SUB, IRDataType.BYTE, reg1=42, value = 1)
+            IRInstruction(Opcode.SUB, IRDataType.BYTE, reg1=42, immediate = 1)
         ))
         irProg.chunks().single().instructions.size shouldBe 2
         val opt = IRPeepholeOptimizer(irProg)
-        opt.optimize()
+        opt.optimize(true, ErrorReporterForTests())
         val instr = irProg.chunks().single().instructions
         instr.size shouldBe 2
         instr[0].opcode shouldBe Opcode.INC
@@ -150,40 +149,40 @@ class TestIRPeepholeOpt: FunSpec({
 
     test("remove useless and/or/xor") {
         val irProg = makeIRProgram(listOf(
-            IRInstruction(Opcode.AND, IRDataType.BYTE, reg1=42, value = 255),
+            IRInstruction(Opcode.AND, IRDataType.BYTE, reg1=42, immediate = 255),
-            IRInstruction(Opcode.AND, IRDataType.WORD, reg1=42, value = 65535),
+            IRInstruction(Opcode.AND, IRDataType.WORD, reg1=42, immediate = 65535),
-            IRInstruction(Opcode.OR, IRDataType.BYTE, reg1=42, value = 0),
+            IRInstruction(Opcode.OR, IRDataType.BYTE, reg1=42, immediate = 0),
-            IRInstruction(Opcode.XOR, IRDataType.BYTE, reg1=42, value = 0),
+            IRInstruction(Opcode.XOR, IRDataType.BYTE, reg1=42, immediate = 0),
-            IRInstruction(Opcode.AND, IRDataType.BYTE, reg1=42, value = 200),
+            IRInstruction(Opcode.AND, IRDataType.BYTE, reg1=42, immediate = 200),
-            IRInstruction(Opcode.AND, IRDataType.WORD, reg1=42, value = 60000),
+            IRInstruction(Opcode.AND, IRDataType.WORD, reg1=42, immediate = 60000),
-            IRInstruction(Opcode.OR, IRDataType.BYTE, reg1=42, value = 1),
+            IRInstruction(Opcode.OR, IRDataType.BYTE, reg1=42, immediate = 1),
-            IRInstruction(Opcode.XOR, IRDataType.BYTE, reg1=42, value = 1)
+            IRInstruction(Opcode.XOR, IRDataType.BYTE, reg1=42, immediate = 1)
         ))
         irProg.chunks().single().instructions.size shouldBe 8
         val opt = IRPeepholeOptimizer(irProg)
-        opt.optimize()
+        opt.optimize(true, ErrorReporterForTests())
         irProg.chunks().single().instructions.size shouldBe 4
     }
 
     test("replace and/or/xor by constant number") {
         val irProg = makeIRProgram(listOf(
-            IRInstruction(Opcode.AND, IRDataType.BYTE, reg1=42, value = 0),
+            IRInstruction(Opcode.AND, IRDataType.BYTE, reg1=42, immediate = 0),
-            IRInstruction(Opcode.AND, IRDataType.WORD, reg1=42, value = 0),
+            IRInstruction(Opcode.AND, IRDataType.WORD, reg1=42, immediate = 0),
-            IRInstruction(Opcode.OR, IRDataType.BYTE, reg1=42, value = 255),
+            IRInstruction(Opcode.OR, IRDataType.BYTE, reg1=42, immediate = 255),
-            IRInstruction(Opcode.OR, IRDataType.WORD, reg1=42, value = 65535)
+            IRInstruction(Opcode.OR, IRDataType.WORD, reg1=42, immediate = 65535)
         ))
         irProg.chunks().single().instructions.size shouldBe 4
         val opt = IRPeepholeOptimizer(irProg)
-        opt.optimize()
+        opt.optimize(true, ErrorReporterForTests())
         val instr = irProg.chunks().single().instructions
         instr.size shouldBe 4
         instr[0].opcode shouldBe Opcode.LOAD
         instr[1].opcode shouldBe Opcode.LOAD
         instr[2].opcode shouldBe Opcode.LOAD
         instr[3].opcode shouldBe Opcode.LOAD
-        instr[0].value shouldBe 0
+        instr[0].immediate shouldBe 0
-        instr[1].value shouldBe 0
+        instr[1].immediate shouldBe 0
-        instr[2].value shouldBe 255
+        instr[2].immediate shouldBe 255
-        instr[3].value shouldBe 65535
+        instr[3].immediate shouldBe 65535
     }
 })

codeGenIntermediate/test/TestVmCodeGen.kt

@@ -0,0 +1,478 @@
+import io.kotest.core.spec.style.FunSpec
+import io.kotest.matchers.ints.shouldBeGreaterThan
+import io.kotest.matchers.shouldBe
+import prog8.code.SymbolTableMaker
+import prog8.code.ast.*
+import prog8.code.core.*
+import prog8.code.target.VMTarget
+import prog8.codegen.vm.VmAssemblyProgram
+import prog8.codegen.vm.VmCodeGen
+import prog8.intermediate.IRSubroutine
+import prog8.intermediate.Opcode
+
+class TestVmCodeGen: FunSpec({
+
+    fun getTestOptions(): CompilationOptions {
+        val target = VMTarget()
+        return CompilationOptions(
+            OutputType.RAW,
+            CbmPrgLauncherType.NONE,
+            ZeropageType.DONTUSE,
+            zpReserved = emptyList(),
+            zpAllowed = CompilationOptions.AllZeropageAllowed,
+            floats = true,
+            noSysInit = false,
+            compTarget = target,
+            loadAddress = target.machine.PROGRAM_LOAD_ADDRESS
+        )
+    }
+
+    test("augmented assigns") {
+//main {
+//    sub start() {
+//        ubyte[] particleX = [1,2,3]
+//        ubyte[] particleDX = [1,2,3]
+//        particleX[2] += particleDX[2]
+//
+//        word @shared xx = 1
+//        xx = -xx
+//        xx += 42
+//        xx += cx16.r0
+//    }
+//}
+        val codegen = VmCodeGen()
+        val program = PtProgram("test", DummyMemsizer, DummyStringEncoder)
+        val block = PtBlock("main", false, SourceCode.Generated("test"), PtBlock.Options(), Position.DUMMY)
+        val sub = PtSub("start", emptyList(), null, Position.DUMMY)
+        sub.add(PtVariable("pi", DataType.UBYTE, ZeropageWish.DONTCARE, PtNumber(DataType.UBYTE, 0.0, Position.DUMMY), null, Position.DUMMY))
+        sub.add(PtVariable("particleX", DataType.ARRAY_UB, ZeropageWish.DONTCARE, null, 3u, Position.DUMMY))
+        sub.add(PtVariable("particleDX", DataType.ARRAY_UB, ZeropageWish.DONTCARE, null, 3u, Position.DUMMY))
+        sub.add(PtVariable("xx", DataType.WORD, ZeropageWish.DONTCARE, PtNumber(DataType.WORD, 1.0, Position.DUMMY), null, Position.DUMMY))
+
+        val assign = PtAugmentedAssign("+=", Position.DUMMY)
+        val target = PtAssignTarget(Position.DUMMY).also {
+            val targetIdx = PtArrayIndexer(DataType.UBYTE, Position.DUMMY).also { idx ->
+                idx.add(PtIdentifier("main.start.particleX", DataType.ARRAY_UB, Position.DUMMY))
+                idx.add(PtNumber(DataType.UBYTE, 2.0, Position.DUMMY))
+            }
+            it.add(targetIdx)
+        }
+        val value = PtArrayIndexer(DataType.UBYTE, Position.DUMMY)
+        value.add(PtIdentifier("main.start.particleDX", DataType.ARRAY_UB, Position.DUMMY))
+        value.add(PtNumber(DataType.UBYTE, 2.0, Position.DUMMY))
+        assign.add(target)
+        assign.add(value)
+        sub.add(assign)
+
+        val prefixAssign = PtAugmentedAssign("-", Position.DUMMY)
+        val prefixTarget = PtAssignTarget(Position.DUMMY).also {
+            it.add(PtIdentifier("main.start.xx", DataType.WORD, Position.DUMMY))
+        }
+        prefixAssign.add(prefixTarget)
+        prefixAssign.add(PtIdentifier("main.start.xx", DataType.WORD, Position.DUMMY))
+        sub.add(prefixAssign)
+
+        val numberAssign = PtAugmentedAssign("+=", Position.DUMMY)
+        val numberAssignTarget = PtAssignTarget(Position.DUMMY).also {
+            it.add(PtIdentifier("main.start.xx", DataType.WORD, Position.DUMMY))
+        }
+        numberAssign.add(numberAssignTarget)
+        numberAssign.add(PtNumber(DataType.WORD, 42.0, Position.DUMMY))
+        sub.add(numberAssign)
+
+        val cxregAssign = PtAugmentedAssign("+=", Position.DUMMY)
+        val cxregAssignTarget = PtAssignTarget(Position.DUMMY).also {
+            it.add(PtIdentifier("main.start.xx", DataType.WORD, Position.DUMMY))
+        }
+        cxregAssign.add(cxregAssignTarget)
+        cxregAssign.add(PtIdentifier("cx16.r0", DataType.UWORD, Position.DUMMY))
+        sub.add(cxregAssign)
+
+        block.add(sub)
+        program.add(block)
+
+        // define the "cx16.r0" virtual register
+        val cx16block = PtBlock("cx16", false, SourceCode.Generated("test"), PtBlock.Options(), Position.DUMMY)
+        cx16block.add(PtMemMapped("r0", DataType.UWORD, 100u, null, Position.DUMMY))
+        program.add(cx16block)
+
+        val options = getTestOptions()
+        val st = SymbolTableMaker(program, options).make()
+        val errors = ErrorReporterForTests()
+        val result = codegen.generate(program, st, options, errors) as VmAssemblyProgram
+        val irChunks = (result.irProgram.blocks.first().children.single() as IRSubroutine).chunks
+        irChunks.size shouldBe 1
+    }
+
+    test("float comparison expressions against zero") {
+//main {
+//    sub start() {
+//        float @shared f1
+//
+//        if f1==0
+//            nop
+//        if f1!=0
+//            nop
+//        if f1>0
+//            nop
+//        if f1<0
+//            nop
+//    }
+//}
+        val codegen = VmCodeGen()
+        val program = PtProgram("test", DummyMemsizer, DummyStringEncoder)
+        val block = PtBlock("main", false, SourceCode.Generated("test"), PtBlock.Options(), Position.DUMMY)
+        val sub = PtSub("start", emptyList(), null, Position.DUMMY)
+        sub.add(PtVariable("f1", DataType.FLOAT, ZeropageWish.DONTCARE, null, null, Position.DUMMY))
+        val if1 = PtIfElse(Position.DUMMY)
+        val cmp1 = PtBinaryExpression("==", DataType.UBYTE, Position.DUMMY)
+        cmp1.add(PtIdentifier("main.start.f1", DataType.FLOAT, Position.DUMMY))
+        cmp1.add(PtNumber(DataType.FLOAT, 0.0, Position.DUMMY))
+        if1.add(cmp1)
+        if1.add(PtNodeGroup().also { it.add(PtNop(Position.DUMMY)) })
+        if1.add(PtNodeGroup().also { it.add(PtNop(Position.DUMMY)) })
+        sub.add(if1)
+        val if2 = PtIfElse(Position.DUMMY)
+        val cmp2 = PtBinaryExpression("!=", DataType.UBYTE, Position.DUMMY)
+        cmp2.add(PtIdentifier("main.start.f1", DataType.FLOAT, Position.DUMMY))
+        cmp2.add(PtNumber(DataType.FLOAT, 0.0, Position.DUMMY))
+        if2.add(cmp2)
+        if2.add(PtNodeGroup().also { it.add(PtNop(Position.DUMMY)) })
+        if2.add(PtNodeGroup().also { it.add(PtNop(Position.DUMMY)) })
+        sub.add(if2)
+        val if3 = PtIfElse(Position.DUMMY)
+        val cmp3 = PtBinaryExpression("<", DataType.UBYTE, Position.DUMMY)
+        cmp3.add(PtIdentifier("main.start.f1", DataType.FLOAT, Position.DUMMY))
+        cmp3.add(PtNumber(DataType.FLOAT, 0.0, Position.DUMMY))
+        if3.add(cmp3)
+        if3.add(PtNodeGroup().also { it.add(PtNop(Position.DUMMY)) })
+        if3.add(PtNodeGroup().also { it.add(PtNop(Position.DUMMY)) })
+        sub.add(if3)
+        val if4 = PtIfElse(Position.DUMMY)
+        val cmp4 = PtBinaryExpression(">", DataType.UBYTE, Position.DUMMY)
+        cmp4.add(PtIdentifier("main.start.f1", DataType.FLOAT, Position.DUMMY))
+        cmp4.add(PtNumber(DataType.FLOAT, 0.0, Position.DUMMY))
+        if4.add(cmp4)
+        if4.add(PtNodeGroup().also { it.add(PtNop(Position.DUMMY)) })
+        if4.add(PtNodeGroup().also { it.add(PtNop(Position.DUMMY)) })
+        sub.add(if4)
+        block.add(sub)
+        program.add(block)
+
+        val options = getTestOptions()
+        val st = SymbolTableMaker(program, options).make()
+        val errors = ErrorReporterForTests()
+        val result = codegen.generate(program, st, options, errors) as VmAssemblyProgram
+        val irChunks = (result.irProgram.blocks.first().children.single() as IRSubroutine).chunks
+        irChunks.size shouldBeGreaterThan 4
+    }
+
+    test("float comparison expressions against nonzero") {
+//main {
+//    sub start() {
+//        float @shared f1
+//
+//        if f1==42
+//            nop
+//        if f1!=42
+//            nop
+//        if f1>42
+//            nop
+//        if f1<42
+//            nop
+//    }
+//}
+        val codegen = VmCodeGen()
+        val program = PtProgram("test", DummyMemsizer, DummyStringEncoder)
+        val block = PtBlock("main", false, SourceCode.Generated("test"), PtBlock.Options(), Position.DUMMY)
+        val sub = PtSub("start", emptyList(), null, Position.DUMMY)
+        sub.add(PtVariable("f1", DataType.FLOAT, ZeropageWish.DONTCARE, null, null, Position.DUMMY))
+        val if1 = PtIfElse(Position.DUMMY)
+        val cmp1 = PtBinaryExpression("==", DataType.UBYTE, Position.DUMMY)
+        cmp1.add(PtIdentifier("main.start.f1", DataType.FLOAT, Position.DUMMY))
+        cmp1.add(PtNumber(DataType.FLOAT, 42.0, Position.DUMMY))
+        if1.add(cmp1)
+        if1.add(PtNodeGroup().also { it.add(PtNop(Position.DUMMY)) })
+        if1.add(PtNodeGroup().also { it.add(PtNop(Position.DUMMY)) })
+        sub.add(if1)
+        val if2 = PtIfElse(Position.DUMMY)
+        val cmp2 = PtBinaryExpression("!=", DataType.UBYTE, Position.DUMMY)
+        cmp2.add(PtIdentifier("main.start.f1", DataType.FLOAT, Position.DUMMY))
+        cmp2.add(PtNumber(DataType.FLOAT, 42.0, Position.DUMMY))
+        if2.add(cmp2)
+        if2.add(PtNodeGroup().also { it.add(PtNop(Position.DUMMY)) })
+        if2.add(PtNodeGroup().also { it.add(PtNop(Position.DUMMY)) })
+        sub.add(if2)
+        val if3 = PtIfElse(Position.DUMMY)
+        val cmp3 = PtBinaryExpression("<", DataType.UBYTE, Position.DUMMY)
+        cmp3.add(PtIdentifier("main.start.f1", DataType.FLOAT, Position.DUMMY))
+        cmp3.add(PtNumber(DataType.FLOAT, 42.0, Position.DUMMY))
+        if3.add(cmp3)
+        if3.add(PtNodeGroup().also { it.add(PtNop(Position.DUMMY)) })
+        if3.add(PtNodeGroup().also { it.add(PtNop(Position.DUMMY)) })
+        sub.add(if3)
+        val if4 = PtIfElse(Position.DUMMY)
+        val cmp4 = PtBinaryExpression(">", DataType.UBYTE, Position.DUMMY)
+        cmp4.add(PtIdentifier("main.start.f1", DataType.FLOAT, Position.DUMMY))
+        cmp4.add(PtNumber(DataType.FLOAT, 42.0, Position.DUMMY))
+        if4.add(cmp4)
+        if4.add(PtNodeGroup().also { it.add(PtNop(Position.DUMMY)) })
+        if4.add(PtNodeGroup().also { it.add(PtNop(Position.DUMMY)) })
+        sub.add(if4)
+        block.add(sub)
+        program.add(block)
+
+        val options = getTestOptions()
+        val st = SymbolTableMaker(program, options).make()
+        val errors = ErrorReporterForTests()
+        val result = codegen.generate(program, st, options, errors) as VmAssemblyProgram
+        val irChunks = (result.irProgram.blocks.first().children.single() as IRSubroutine).chunks
+        irChunks.size shouldBeGreaterThan 4
+    }
+
+    test("float conditional jump") {
+//main {
+//    sub start() {
+//        float @shared f1
+//
+//        if f1==42
+//            goto $c000
+//        if f1>42
+//            goto $c000
+//    }
+//}
+        val codegen = VmCodeGen()
+        val program = PtProgram("test", DummyMemsizer, DummyStringEncoder)
+        val block = PtBlock("main", false, SourceCode.Generated("test"), PtBlock.Options(), Position.DUMMY)
+        val sub = PtSub("start", emptyList(), null, Position.DUMMY)
+        sub.add(PtVariable("f1", DataType.FLOAT, ZeropageWish.DONTCARE, null, null, Position.DUMMY))
+        val if1 = PtIfElse(Position.DUMMY)
+        val cmp1 = PtBinaryExpression("==", DataType.UBYTE, Position.DUMMY)
+        cmp1.add(PtIdentifier("main.start.f1", DataType.FLOAT, Position.DUMMY))
+        cmp1.add(PtNumber(DataType.FLOAT, 42.0, Position.DUMMY))
+        if1.add(cmp1)
+        if1.add(PtNodeGroup().also { it.add(PtJump(null, 0xc000u, Position.DUMMY)) })
+        if1.add(PtNodeGroup())
+        sub.add(if1)
+        val if2 = PtIfElse(Position.DUMMY)
+        val cmp2 = PtBinaryExpression(">", DataType.UBYTE, Position.DUMMY)
+        cmp2.add(PtIdentifier("main.start.f1", DataType.FLOAT, Position.DUMMY))
+        cmp2.add(PtNumber(DataType.FLOAT, 42.0, Position.DUMMY))
+        if2.add(cmp2)
+        if2.add(PtNodeGroup().also { it.add(PtJump(null, 0xc000u, Position.DUMMY)) })
+        if2.add(PtNodeGroup())
+        sub.add(if2)
+        block.add(sub)
+        program.add(block)
+
+        val options = getTestOptions()
+        val st = SymbolTableMaker(program, options).make()
+        val errors = ErrorReporterForTests()
+        val result = codegen.generate(program, st, options, errors) as VmAssemblyProgram
+        val irChunks = (result.irProgram.blocks.first().children.single() as IRSubroutine).chunks
+        irChunks.size shouldBe 1
+    }
+
+    test("integer comparison expressions against zero") {
+//main {
+//    sub start() {
+//        byte @shared sb1
+//
+//        if sb1==0
+//            nop
+//        if sb1!=0
+//            nop
+//        if sb1>0
+//            nop
+//        if sb1<0
+//            nop
+//    }
+//}
+        val codegen = VmCodeGen()
+        val program = PtProgram("test", DummyMemsizer, DummyStringEncoder)
+        val block = PtBlock("main", false, SourceCode.Generated("test"), PtBlock.Options(), Position.DUMMY)
+        val sub = PtSub("start", emptyList(), null, Position.DUMMY)
+        sub.add(PtVariable("sb1", DataType.BYTE, ZeropageWish.DONTCARE, null, null, Position.DUMMY))
+        val if1 = PtIfElse(Position.DUMMY)
+        val cmp1 = PtBinaryExpression("==", DataType.BYTE, Position.DUMMY)
+        cmp1.add(PtIdentifier("main.start.sb1", DataType.BYTE, Position.DUMMY))
+        cmp1.add(PtNumber(DataType.BYTE, 0.0, Position.DUMMY))
+        if1.add(cmp1)
+        if1.add(PtNodeGroup().also { it.add(PtNop(Position.DUMMY)) })
+        if1.add(PtNodeGroup().also { it.add(PtNop(Position.DUMMY)) })
+        sub.add(if1)
+        val if2 = PtIfElse(Position.DUMMY)
+        val cmp2 = PtBinaryExpression("!=", DataType.BYTE, Position.DUMMY)
+        cmp2.add(PtIdentifier("main.start.sb1", DataType.BYTE, Position.DUMMY))
+        cmp2.add(PtNumber(DataType.BYTE, 0.0, Position.DUMMY))
+        if2.add(cmp2)
+        if2.add(PtNodeGroup().also { it.add(PtNop(Position.DUMMY)) })
+        if2.add(PtNodeGroup().also { it.add(PtNop(Position.DUMMY)) })
+        sub.add(if2)
+        val if3 = PtIfElse(Position.DUMMY)
+        val cmp3 = PtBinaryExpression("<", DataType.BYTE, Position.DUMMY)
+        cmp3.add(PtIdentifier("main.start.sb1", DataType.BYTE, Position.DUMMY))
+        cmp3.add(PtNumber(DataType.BYTE, 0.0, Position.DUMMY))
+        if3.add(cmp3)
+        if3.add(PtNodeGroup().also { it.add(PtNop(Position.DUMMY)) })
+        if3.add(PtNodeGroup().also { it.add(PtNop(Position.DUMMY)) })
+        sub.add(if3)
+        val if4 = PtIfElse(Position.DUMMY)
+        val cmp4 = PtBinaryExpression(">", DataType.BYTE, Position.DUMMY)
+        cmp4.add(PtIdentifier("main.start.sb1", DataType.BYTE, Position.DUMMY))
+        cmp4.add(PtNumber(DataType.BYTE, 0.0, Position.DUMMY))
+        if4.add(cmp4)
+        if4.add(PtNodeGroup().also { it.add(PtNop(Position.DUMMY)) })
+        if4.add(PtNodeGroup().also { it.add(PtNop(Position.DUMMY)) })
+        sub.add(if4)
+        block.add(sub)
+        program.add(block)
+
+        val options = getTestOptions()
+        val st = SymbolTableMaker(program, options).make()
+        val errors = ErrorReporterForTests()
+        val result = codegen.generate(program, st, options, errors) as VmAssemblyProgram
+        val irChunks = (result.irProgram.blocks.first().children.single() as IRSubroutine).chunks
+        irChunks.size shouldBeGreaterThan 4
+    }
+
+    test("integer comparison expressions against nonzero") {
+//main {
+//    sub start() {
+//        byte @shared sb1
+//
+//        if sb1==42
+//            nop
+//        if sb1!=42
+//            nop
+//        if sb1>42
+//            nop
+//        if sb1<42
+//            nop
+//    }
+//}
+        val codegen = VmCodeGen()
+        val program = PtProgram("test", DummyMemsizer, DummyStringEncoder)
+        val block = PtBlock("main", false, SourceCode.Generated("test"), PtBlock.Options(), Position.DUMMY)
+        val sub = PtSub("start", emptyList(), null, Position.DUMMY)
+        sub.add(PtVariable("sb1", DataType.BYTE, ZeropageWish.DONTCARE, null, null, Position.DUMMY))
+        val if1 = PtIfElse(Position.DUMMY)
+        val cmp1 = PtBinaryExpression("==", DataType.BYTE, Position.DUMMY)
+        cmp1.add(PtIdentifier("main.start.sb1", DataType.BYTE, Position.DUMMY))
+        cmp1.add(PtNumber(DataType.BYTE, 42.0, Position.DUMMY))
+        if1.add(cmp1)
+        if1.add(PtNodeGroup().also { it.add(PtNop(Position.DUMMY)) })
+        if1.add(PtNodeGroup().also { it.add(PtNop(Position.DUMMY)) })
+        sub.add(if1)
+        val if2 = PtIfElse(Position.DUMMY)
+        val cmp2 = PtBinaryExpression("!=", DataType.BYTE, Position.DUMMY)
+        cmp2.add(PtIdentifier("main.start.sb1", DataType.BYTE, Position.DUMMY))
+        cmp2.add(PtNumber(DataType.BYTE, 42.0, Position.DUMMY))
+        if2.add(cmp2)
+        if2.add(PtNodeGroup().also { it.add(PtNop(Position.DUMMY)) })
+        if2.add(PtNodeGroup().also { it.add(PtNop(Position.DUMMY)) })
+        sub.add(if2)
+        val if3 = PtIfElse(Position.DUMMY)
+        val cmp3 = PtBinaryExpression("<", DataType.BYTE, Position.DUMMY)
+        cmp3.add(PtIdentifier("main.start.sb1", DataType.BYTE, Position.DUMMY))
+        cmp3.add(PtNumber(DataType.BYTE, 42.0, Position.DUMMY))
+        if3.add(cmp3)
+        if3.add(PtNodeGroup().also { it.add(PtNop(Position.DUMMY)) })
+        if3.add(PtNodeGroup().also { it.add(PtNop(Position.DUMMY)) })
+        sub.add(if3)
+        val if4 = PtIfElse(Position.DUMMY)
+        val cmp4 = PtBinaryExpression(">", DataType.BYTE, Position.DUMMY)
+        cmp4.add(PtIdentifier("main.start.sb1", DataType.BYTE, Position.DUMMY))
+        cmp4.add(PtNumber(DataType.BYTE, 42.0, Position.DUMMY))
+        if4.add(cmp4)
+        if4.add(PtNodeGroup().also { it.add(PtNop(Position.DUMMY)) })
+        if4.add(PtNodeGroup().also { it.add(PtNop(Position.DUMMY)) })
+        sub.add(if4)
+        block.add(sub)
+        program.add(block)
+
+        val options = getTestOptions()
+        val st = SymbolTableMaker(program, options).make()
+        val errors = ErrorReporterForTests()
+        val result = codegen.generate(program, st, options, errors) as VmAssemblyProgram
+        val irChunks = (result.irProgram.blocks.first().children.single() as IRSubroutine).chunks
+        irChunks.size shouldBeGreaterThan 4
+    }
+
+    test("integer conditional jump") {
+//main {
+//    sub start() {
+//        ubyte @shared ub1
+//
+//        if ub1==42
+//            goto $c000
+//        if ub1>42
+//            goto $c000
+//    }
+//}
+        val codegen = VmCodeGen()
+        val program = PtProgram("test", DummyMemsizer, DummyStringEncoder)
+        val block = PtBlock("main", false, SourceCode.Generated("test"), PtBlock.Options(), Position.DUMMY)
+        val sub = PtSub("start", emptyList(), null, Position.DUMMY)
+        sub.add(PtVariable("ub1", DataType.UBYTE, ZeropageWish.DONTCARE, null, null, Position.DUMMY))
+        val if1 = PtIfElse(Position.DUMMY)
+        val cmp1 = PtBinaryExpression("==", DataType.UBYTE, Position.DUMMY)
+        cmp1.add(PtIdentifier("main.start.ub1", DataType.UBYTE, Position.DUMMY))
+        cmp1.add(PtNumber(DataType.UBYTE, 42.0, Position.DUMMY))
+        if1.add(cmp1)
+        if1.add(PtNodeGroup().also { it.add(PtJump(null, 0xc000u, Position.DUMMY)) })
+        if1.add(PtNodeGroup())
+        sub.add(if1)
+        val if2 = PtIfElse(Position.DUMMY)
+        val cmp2 = PtBinaryExpression(">", DataType.UBYTE, Position.DUMMY)
+        cmp2.add(PtIdentifier("main.start.ub1", DataType.UBYTE, Position.DUMMY))
+        cmp2.add(PtNumber(DataType.UBYTE, 42.0, Position.DUMMY))
+        if2.add(cmp2)
+        if2.add(PtNodeGroup().also { it.add(PtJump(null, 0xc000u, Position.DUMMY)) })
+        if2.add(PtNodeGroup())
+        sub.add(if2)
+        block.add(sub)
+        program.add(block)
+
+        val options = getTestOptions()
+        val st = SymbolTableMaker(program, options).make()
+        val errors = ErrorReporterForTests()
+        val result = codegen.generate(program, st, options, errors) as VmAssemblyProgram
+        val irChunks = (result.irProgram.blocks.first().children.single() as IRSubroutine).chunks
+        irChunks.size shouldBe 1
+    }
+
+    test("romsub allowed in ir-codegen") {
+//main {
+//    romsub $5000 = routine()
+//
+//    sub start()  {
+//        routine()
+//    }
+//}
+        val codegen = VmCodeGen()
+        val program = PtProgram("test", DummyMemsizer, DummyStringEncoder)
+        val block = PtBlock("main", false, SourceCode.Generated("test"), PtBlock.Options(), Position.DUMMY)
+        val romsub = PtAsmSub("routine", 0x5000u, setOf(CpuRegister.Y), emptyList(), emptyList(), false, Position.DUMMY)
+        block.add(romsub)
+        val sub = PtSub("start", emptyList(), null, Position.DUMMY)
+        val call = PtFunctionCall("main.routine", true, DataType.UNDEFINED, Position.DUMMY)
+        sub.add(call)
+        block.add(sub)
+        program.add(block)
+
+        val options = getTestOptions()
+        val st = SymbolTableMaker(program, options).make()
+        val errors = ErrorReporterForTests()
+        val result = codegen.generate(program, st, options, errors) as VmAssemblyProgram
+        val irChunks = (result.irProgram.blocks.first().children.single() as IRSubroutine).chunks
+        irChunks.size shouldBe 1
+        irChunks[0].instructions.size shouldBe 2
+        val preparecallInstr = irChunks[0].instructions[0]
+        preparecallInstr.opcode shouldBe Opcode.PREPARECALL
+        preparecallInstr.immediate shouldBe 0
+        val callInstr = irChunks[0].instructions[1]
+        callInstr.opcode shouldBe Opcode.CALL
+        callInstr.address shouldBe 0x5000
+    }
+})

codeGenVirtual/codeGenVirtual.iml

@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<module version="4">
+  <component name="NewModuleRootManager" inherit-compiler-output="true">
+    <exclude-output />
+    <orderEntry type="inheritedJdk" />
+    <orderEntry type="sourceFolder" forTests="false" />
+  </component>
+</module>

codeOptimizers/build.gradle

@@ -27,16 +27,17 @@ dependencies {
     implementation project(':codeCore')
     implementation project(':compilerAst')
     implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8"
+    implementation "com.michael-bull.kotlin-result:kotlin-result-jvm:1.1.18"
     // implementation "org.jetbrains.kotlin:kotlin-reflect"
 }
 
 sourceSets {
     main {
         java {
-            srcDirs = ["${project.projectDir}/src"]
+            srcDir "${project.projectDir}/src"
         }
         resources {
-            srcDirs = ["${project.projectDir}/res"]
+            srcDir "${project.projectDir}/res"
         }
     }
 }

codeOptimizers/codeOptimizers.iml

@@ -11,5 +11,6 @@
     <orderEntry type="library" name="KotlinJavaRuntime" level="project" />
     <orderEntry type="module" module-name="codeCore" />
     <orderEntry type="module" module-name="compilerAst" />
+    <orderEntry type="library" name="michael.bull.kotlin.result.jvm" level="project" />
   </component>
 </module>

codeOptimizers/src/prog8/optimizer/BinExprSplitter.kt

@@ -1,125 +0,0 @@
-package prog8.optimizer
-
-import prog8.ast.IStatementContainer
-import prog8.ast.Node
-import prog8.ast.Program
-import prog8.ast.expressions.BinaryExpression
-import prog8.ast.expressions.IdentifierReference
-import prog8.ast.expressions.TypecastExpression
-import prog8.ast.getTempVar
-import prog8.ast.statements.AssignTarget
-import prog8.ast.statements.Assignment
-import prog8.ast.statements.AssignmentOrigin
-import prog8.ast.walk.AstWalker
-import prog8.ast.walk.IAstModification
-import prog8.code.core.AugmentAssignmentOperators
-import prog8.code.core.CompilationOptions
-import prog8.code.core.DataType
-import prog8.code.target.VMTarget
-
-
-class BinExprSplitter(private val program: Program, private val options: CompilationOptions) : AstWalker() {
-
-    override fun after(assignment: Assignment, parent: Node): Iterable<IAstModification> {
-
-        if(options.compTarget.name == VMTarget.NAME)
-            return noModifications  // don't split expressions when targeting the vm codegen, it handles nested expressions well
-
-        if(assignment.value.inferType(program) istype DataType.FLOAT && !options.optimizeFloatExpressions)
-            return noModifications
-
-        val binExpr = assignment.value as? BinaryExpression
-        if (binExpr != null) {
-
-/*
-
-Reduce the complexity of a (binary) expression that has to be evaluated on the eval stack,
-by attempting to splitting it up into individual simple steps.
-We only consider a binary expression *one* level deep (so the operands must not be a combined expression)
-
-
-X =      BinExpr                                    X   =   LeftExpr
-        <operator>                                     followed by
-          /   \             IF 'X' not used         X   =   BinExpr
-         /     \             IN expression ==>             <operator>
-        /       \                                           /   \
-    LeftExpr.  RightExpr.                                  /     \
-                                                          X     RightExpr.
-
-
- */
-            if(binExpr.operator in AugmentAssignmentOperators && isSimpleTarget(assignment.target)) {
-                if(assignment.target isSameAs binExpr.right)
-                    return noModifications
-                if(assignment.target isSameAs binExpr.left) {
-                    if(binExpr.right.isSimple)
-                        return noModifications
-                    val leftBx = binExpr.left as? BinaryExpression
-                    if(leftBx!=null && (!leftBx.left.isSimple || !leftBx.right.isSimple))
-                        return noModifications
-                    val rightBx = binExpr.right as? BinaryExpression
-                    if(rightBx!=null && (!rightBx.left.isSimple || !rightBx.right.isSimple))
-                        return noModifications
-
-                      // TODO below attempts to remove stack-based evaluated expressions, but often the resulting code is BIGGER, and SLOWER.
-//                    val dt = assignment.target.inferType(program)
-//                    if(!dt.isInteger)
-//                        return noModifications
-//                    val tempVar = IdentifierReference(getTempVarName(dt), binExpr.right.position)
-//                    val assignTempVar = Assignment(
-//                        AssignTarget(tempVar, null, null, binExpr.right.position),
-//                        binExpr.right, binExpr.right.position
-//                    )
-//                    return listOf(
-//                        IAstModification.InsertBefore(assignment, assignTempVar, assignment.parent as IStatementContainer),
-//                        IAstModification.ReplaceNode(binExpr.right, tempVar.copy(), binExpr)
-//                    )
-                }
-
-                if(binExpr.right.isSimple) {
-                    val firstAssign = Assignment(assignment.target.copy(), binExpr.left, AssignmentOrigin.OPTIMIZER, binExpr.left.position)
-                    val targetExpr = assignment.target.toExpression()
-                    val augExpr = BinaryExpression(targetExpr, binExpr.operator, binExpr.right, binExpr.right.position)
-                    return listOf(
-                        IAstModification.ReplaceNode(binExpr, augExpr, assignment),
-                        IAstModification.InsertBefore(assignment, firstAssign, assignment.parent as IStatementContainer)
-                    )
-                }
-            }
-
-            // TODO further unraveling of binary expression trees into flat statements.
-            // however this should probably be done in a more generic way to also work on
-            // the expressiontrees that are not used in an assignment statement...
-        }
-
-        val typecast = assignment.value as? TypecastExpression
-        if(typecast!=null) {
-            val origExpr = typecast.expression as? BinaryExpression
-            if(origExpr!=null && options.compTarget.name!=VMTarget.NAME) {
-                // it's a typecast of a binary expression.
-                // we can see if we can unwrap the binary expression by working on a new temporary variable
-                // (that has the type of the expression), and then finally doing the typecast.
-                // Once it's outside the typecast, the regular splitting can commence.
-                val tempvarDt = origExpr.inferType(program).getOr(DataType.UNDEFINED)
-                val (tempVarName, _) = program.getTempVar(tempvarDt)
-                val assignTempVar = Assignment(
-                    AssignTarget(IdentifierReference(tempVarName, typecast.position), null, null, typecast.position),
-                    typecast.expression, AssignmentOrigin.OPTIMIZER, typecast.position
-                )
-                return listOf(
-                    IAstModification.InsertBefore(assignment, assignTempVar, parent as IStatementContainer),
-                    IAstModification.ReplaceNode(typecast.expression, IdentifierReference(tempVarName, typecast.position), typecast)
-                )
-            }
-        }
-
-        return noModifications
-    }
-
-    private fun isSimpleTarget(target: AssignTarget) =
-            if (target.identifier!=null || target.memoryAddress!=null)
-                !target.isIOAddress(options.compTarget.machine)
-            else
-                false
-
-}