version 8.1

vm code can do this via inline assembly

.idea/codeStyles/Project.xml

@@ -0,0 +1,10 @@
+<component name="ProjectCodeStyleConfiguration">
+  <code_scheme name="Project" version="173">
+    <JetCodeStyleSettings>
+      <option name="CODE_STYLE_DEFAULTS" value="KOTLIN_OFFICIAL" />
+    </JetCodeStyleSettings>
+    <codeStyleSettings language="kotlin">
+      <option name="CODE_STYLE_DEFAULTS" value="KOTLIN_OFFICIAL" />
+    </codeStyleSettings>
+  </code_scheme>
+</component>

.idea/codeStyles/codeStyleConfig.xml

@@ -0,0 +1,5 @@
+<component name="ProjectCodeStyleConfiguration">
+  <state>
+    <option name="USE_PER_PROJECT_SETTINGS" value="true" />
+  </state>
+</component>

.idea/compiler.xml

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

.idea/inspectionProfiles/Project_Default.xml

@@ -7,6 +7,7 @@
         <language isEnabled="false" name="Groovy" />
       </Languages>
     </inspection_tool>
+    <inspection_tool class="IncompleteDestructuring" enabled="true" level="WARNING" enabled_by_default="true" />
     <inspection_tool class="PyInterpreterInspection" enabled="false" level="WARNING" enabled_by_default="false" />
     <inspection_tool class="SpellCheckingInspection" enabled="true" level="TYPO" enabled_by_default="true">
       <option name="processCode" value="false" />

.idea/libraries/antlr_antlr4.xml

@@ -1,15 +1,15 @@
 <component name="libraryTable">
   <library name="antlr.antlr4" type="repository">
-    <properties maven-id="org.antlr:antlr4:4.9.2">
+    <properties maven-id="org.antlr:antlr4:4.10.1">
       <exclude>
         <dependency maven-id="com.ibm.icu:icu4j" />
       </exclude>
     </properties>
     <CLASSES>
-      <root url="jar://$MAVEN_REPOSITORY$/org/antlr/antlr4/4.9.2/antlr4-4.9.2.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/antlr/antlr4-runtime/4.9.2/antlr4-runtime-4.9.2.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/antlr/antlr-runtime/3.5.2/antlr-runtime-3.5.2.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/antlr/ST4/4.3/ST4-4.3.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/antlr/antlr4/4.10.1/antlr4-4.10.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/antlr/antlr4-runtime/4.10.1/antlr4-runtime-4.10.1.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/ST4/4.3.3/ST4-4.3.3.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/abego/treelayout/org.abego.treelayout.core/1.0.3/org.abego.treelayout.core-1.0.3.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/glassfish/javax.json/1.0.4/javax.json-1.0.4.jar!/" />
     </CLASSES>

.idea/libraries/hamcrest.xml

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

.idea/libraries/io_kotest_assertions_core_jvm.xml

@@ -1,20 +1,21 @@
 <component name="libraryTable">
   <library name="io.kotest.assertions.core.jvm" type="repository">
-    <properties maven-id="io.kotest:kotest-assertions-core-jvm:4.6.3" />
+    <properties maven-id="io.kotest:kotest-assertions-core-jvm:5.1.0" />
     <CLASSES>
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-core-jvm/4.6.3/kotest-assertions-core-jvm-4.6.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk8/1.5.0/kotlin-stdlib-jdk8-1.5.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/1.5.0/kotlin-stdlib-1.5.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-core-jvm/5.1.0/kotest-assertions-core-jvm-5.1.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk8/1.6.10/kotlin-stdlib-jdk8-1.6.10.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/1.6.10/kotlin-stdlib-1.6.10.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/annotations/13.0/annotations-13.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk7/1.5.0/kotlin-stdlib-jdk7-1.5.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-shared-jvm/4.6.3/kotest-assertions-shared-jvm-4.6.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/github/java-diff-utils/java-diff-utils/4.9/java-diff-utils-4.9.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-jdk8/1.5.0/kotlinx-coroutines-jdk8-1.5.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-reflect/1.5.0/kotlin-reflect-1.5.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-core-jvm/1.5.0/kotlinx-coroutines-core-jvm-1.5.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-common/1.5.0/kotlin-stdlib-common-1.5.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-common-jvm/4.6.3/kotest-common-jvm-4.6.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-api-jvm/4.6.3/kotest-assertions-api-jvm-4.6.3.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk7/1.6.10/kotlin-stdlib-jdk7-1.6.10.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-shared-jvm/5.1.0/kotest-assertions-shared-jvm-5.1.0.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/opentest4j/opentest4j/1.2.0/opentest4j-1.2.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-jdk8/1.6.0/kotlinx-coroutines-jdk8-1.6.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-reflect/1.6.10/kotlin-reflect-1.6.10.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-core-jvm/1.6.0/kotlinx-coroutines-core-jvm-1.6.0.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-common-jvm/5.1.0/kotest-common-jvm-5.1.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-api-jvm/5.1.0/kotest-assertions-api-jvm-5.1.0.jar!/" />
     </CLASSES>
     <JAVADOC />
     <SOURCES />

.idea/libraries/io_kotest_property_jvm.xml

@@ -1,22 +1,22 @@
 <component name="libraryTable">
   <library name="io.kotest.property.jvm" type="repository">
-    <properties maven-id="io.kotest:kotest-property-jvm:4.6.3" />
+    <properties maven-id="io.kotest:kotest-property-jvm:5.1.0" />
     <CLASSES>
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-property-jvm/4.6.3/kotest-property-jvm-4.6.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk8/1.5.0/kotlin-stdlib-jdk8-1.5.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/1.5.0/kotlin-stdlib-1.5.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-property-jvm/5.1.0/kotest-property-jvm-5.1.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-common-jvm/5.1.0/kotest-common-jvm-5.1.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-shared-jvm/5.1.0/kotest-assertions-shared-jvm-5.1.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-api-jvm/5.1.0/kotest-assertions-api-jvm-5.1.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-jdk8/1.6.0/kotlinx-coroutines-jdk8-1.6.0.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-jdk8/1.6.10/kotlin-stdlib-jdk8-1.6.10.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/1.6.10/kotlin-stdlib-1.6.10.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/annotations/13.0/annotations-13.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk7/1.5.0/kotlin-stdlib-jdk7-1.5.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-common-jvm/4.6.3/kotest-common-jvm-4.6.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-shared-jvm/4.6.3/kotest-assertions-shared-jvm-4.6.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-api-jvm/4.6.3/kotest-assertions-api-jvm-4.6.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-jdk8/1.5.0/kotlinx-coroutines-jdk8-1.5.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/github/java-diff-utils/java-diff-utils/4.9/java-diff-utils-4.9.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/com/github/mifmif/generex/1.0.2/generex-1.0.2.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/dk/brics/automaton/automaton/1.11-8/automaton-1.11-8.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-reflect/1.5.0/kotlin-reflect-1.5.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-core-jvm/1.5.0/kotlinx-coroutines-core-jvm-1.5.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-common/1.5.0/kotlin-stdlib-common-1.5.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk7/1.6.10/kotlin-stdlib-jdk7-1.6.10.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-reflect/1.6.10/kotlin-reflect-1.6.10.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-core-jvm/1.6.0/kotlinx-coroutines-core-jvm-1.6.0.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/github/java-diff-utils/java-diff-utils/4.11/java-diff-utils-4.11.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/com/github/curious-odd-man/rgxgen/1.3/rgxgen-1.3.jar!/" />
     </CLASSES>
     <JAVADOC />
     <SOURCES />

.idea/libraries/io_kotest_runner_junit5_jvm.xml

@@ -1,54 +1,51 @@
 <component name="libraryTable">
   <library name="io.kotest.runner.junit5.jvm" type="repository">
-    <properties maven-id="io.kotest:kotest-runner-junit5-jvm:4.6.3" />
+    <properties maven-id="io.kotest:kotest-runner-junit5-jvm:5.1.0" />
     <CLASSES>
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-runner-junit5-jvm/4.6.3/kotest-runner-junit5-jvm-4.6.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-framework-api-jvm/4.6.3/kotest-framework-api-jvm-4.6.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-shared-jvm/4.6.3/kotest-assertions-shared-jvm-4.6.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/github/java-diff-utils/java-diff-utils/4.9/java-diff-utils-4.9.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-common-jvm/4.6.3/kotest-common-jvm-4.6.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-framework-engine-jvm/4.6.3/kotest-framework-engine-jvm-4.6.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/github/classgraph/classgraph/4.8.105/classgraph-4.8.105.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-runner-junit5-jvm/5.1.0/kotest-runner-junit5-jvm-5.1.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-framework-api-jvm/5.1.0/kotest-framework-api-jvm-5.1.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-test-jvm/1.6.0/kotlinx-coroutines-test-jvm-1.6.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-shared-jvm/5.1.0/kotest-assertions-shared-jvm-5.1.0.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/kotest/kotest-common-jvm/5.1.0/kotest-common-jvm-5.1.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-framework-engine-jvm/5.1.0/kotest-framework-engine-jvm-5.1.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/github/classgraph/classgraph/4.8.138/classgraph-4.8.138.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/com/github/ajalt/mordant/1.2.1/mordant-1.2.1.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/com/github/ajalt/colormath/1.2.0/colormath-1.2.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-script-util/1.5.0/kotlin-script-util-1.5.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/intellij/deps/trove4j/1.0.20181211/trove4j-1.0.20181211.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-daemon-client/1.5.0/kotlin-daemon-client-1.5.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-core/1.3.8/kotlinx-coroutines-core-1.3.8.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-scripting-jvm/1.5.0/kotlin-scripting-jvm-1.5.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-scripting-common/1.5.0/kotlin-scripting-common-1.5.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-debug/1.6.0/kotlinx-coroutines-debug-1.6.0.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://$MAVEN_REPOSITORY$/org/opentest4j/opentest4j/1.2.0/opentest4j-1.2.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-framework-discovery-jvm/4.6.3/kotest-framework-discovery-jvm-4.6.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-core-jvm/4.6.3/kotest-assertions-core-jvm-4.6.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-jdk8/1.5.0/kotlinx-coroutines-jdk8-1.5.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-api-jvm/4.6.3/kotest-assertions-api-jvm-4.6.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-extensions-jvm/4.6.3/kotest-extensions-jvm-4.6.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/commons-io/commons-io/2.6/commons-io-2.6.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/mockk/mockk/1.9.3/mockk-1.9.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/mockk/mockk-common/1.9.3/mockk-common-1.9.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/mockk/mockk-dsl/1.9.3/mockk-dsl-1.9.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/mockk/mockk-dsl-jvm/1.9.3/mockk-dsl-jvm-1.9.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/mockk/mockk-agent-jvm/1.9.3/mockk-agent-jvm-1.9.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/mockk/mockk-agent-api/1.9.3/mockk-agent-api-1.9.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/mockk/mockk-agent-common/1.9.3/mockk-agent-common-1.9.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/objenesis/objenesis/3.0.1/objenesis-3.0.1.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/net/bytebuddy/byte-buddy/1.9.10/byte-buddy-1.9.10.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/net/bytebuddy/byte-buddy-agent/1.9.10/byte-buddy-agent-1.9.10.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-framework-concurrency-jvm/4.6.3/kotest-framework-concurrency-jvm-4.6.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-core-jvm/1.5.0/kotlinx-coroutines-core-jvm-1.5.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-common/1.5.0/kotlin-stdlib-common-1.5.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/junit/platform/junit-platform-engine/1.6.2/junit-platform-engine-1.6.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-framework-discovery-jvm/5.1.0/kotest-framework-discovery-jvm-5.1.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-core-jvm/5.1.0/kotest-assertions-core-jvm-5.1.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-jdk8/1.6.0/kotlinx-coroutines-jdk8-1.6.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-api-jvm/5.1.0/kotest-assertions-api-jvm-5.1.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-extensions-jvm/5.1.0/kotest-extensions-jvm-5.1.0.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/mockk/mockk/1.12.2/mockk-1.12.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/mockk/mockk-dsl-jvm/1.12.2/mockk-dsl-jvm-1.12.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/mockk/mockk-dsl/1.12.2/mockk-dsl-1.12.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/mockk/mockk-common/1.12.2/mockk-common-1.12.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/mockk/mockk-agent-jvm/1.12.2/mockk-agent-jvm-1.12.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/mockk/mockk-agent-api/1.12.2/mockk-agent-api-1.12.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/mockk/mockk-agent-common/1.12.2/mockk-agent-common-1.12.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/objenesis/objenesis/3.1/objenesis-3.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/net/bytebuddy/byte-buddy/1.12.5/byte-buddy-1.12.5.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/net/bytebuddy/byte-buddy-agent/1.12.5/byte-buddy-agent-1.12.5.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-framework-concurrency-jvm/5.1.0/kotest-framework-concurrency-jvm-5.1.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-core-jvm/1.6.0/kotlinx-coroutines-core-jvm-1.6.0.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://$MAVEN_REPOSITORY$/org/junit/platform/junit-platform-engine/1.7.2/junit-platform-engine-1.7.2.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/apiguardian/apiguardian-api/1.1.0/apiguardian-api-1.1.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/junit/platform/junit-platform-commons/1.6.2/junit-platform-commons-1.6.2.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/junit/platform/junit-platform-suite-api/1.6.2/junit-platform-suite-api-1.6.2.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/junit/platform/junit-platform-launcher/1.6.2/junit-platform-launcher-1.6.2.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/junit/jupiter/junit-jupiter-api/5.6.2/junit-jupiter-api-5.6.2.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk8/1.5.0/kotlin-stdlib-jdk8-1.5.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/1.5.0/kotlin-stdlib-1.5.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/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-jdk8/1.6.10/kotlin-stdlib-jdk8-1.6.10.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/1.6.10/kotlin-stdlib-1.6.10.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/annotations/13.0/annotations-13.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk7/1.5.0/kotlin-stdlib-jdk7-1.5.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-script-runtime/1.5.0/kotlin-script-runtime-1.5.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-reflect/1.5.0/kotlin-reflect-1.5.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk7/1.6.10/kotlin-stdlib-jdk7-1.6.10.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-reflect/1.6.10/kotlin-reflect-1.6.10.jar!/" />
     </CLASSES>
     <JAVADOC />
     <SOURCES />

.idea/libraries/jetbrains_kotlinx_cli_jvm.xml

@@ -1,8 +1,8 @@
 <component name="libraryTable">
   <library name="jetbrains.kotlinx.cli.jvm" type="repository">
-    <properties include-transitive-deps="false" maven-id="org.jetbrains.kotlinx:kotlinx-cli-jvm:0.3.3" />
+    <properties include-transitive-deps="false" maven-id="org.jetbrains.kotlinx:kotlinx-cli-jvm:0.3.4" />
     <CLASSES>
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-cli-jvm/0.3.3/kotlinx-cli-jvm-0.3.3.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-cli-jvm/0.3.4/kotlinx-cli-jvm-0.3.4.jar!/" />
     </CLASSES>
     <JAVADOC />
     <SOURCES />

.idea/libraries/junit_jupiter.xml

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

.idea/libraries/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:1.1.12" />
+    <properties maven-id="com.michael-bull.kotlin-result:kotlin-result-jvm:1.1.14" />
     <CLASSES>
-      <root url="jar://$MAVEN_REPOSITORY$/com/michael-bull/kotlin-result/kotlin-result-jvm/1.1.12/kotlin-result-jvm-1.1.12.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk8/1.5.10/kotlin-stdlib-jdk8-1.5.10.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/1.5.10/kotlin-stdlib-1.5.10.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/com/michael-bull/kotlin-result/kotlin-result-jvm/1.1.14/kotlin-result-jvm-1.1.14.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk8/1.6.10/kotlin-stdlib-jdk8-1.6.10.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/1.6.10/kotlin-stdlib-1.6.10.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/annotations/13.0/annotations-13.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk7/1.5.10/kotlin-stdlib-jdk7-1.5.10.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-common/1.5.10/kotlin-stdlib-common-1.5.10.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk7/1.6.10/kotlin-stdlib-jdk7-1.6.10.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-common/1.6.10/kotlin-stdlib-common-1.6.10.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:1.7.30" />
+    <properties maven-id="org.slf4j:slf4j-simple:1.7.36" />
     <CLASSES>
-      <root url="jar://$MAVEN_REPOSITORY$/org/slf4j/slf4j-simple/1.7.30/slf4j-simple-1.7.30.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/slf4j/slf4j-api/1.7.30/slf4j-api-1.7.30.jar!/" />
+      <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-api/1.7.36/slf4j-api-1.7.36.jar!/" />
     </CLASSES>
     <JAVADOC />
     <SOURCES />

.idea/misc.xml

@@ -19,7 +19,7 @@
   <component name="FrameworkDetectionExcludesConfiguration">
     <type id="Python" />
   </component>
-  <component name="ProjectRootManager" version="2" languageLevel="JDK_11" project-jdk-name="Kotlin SDK" project-jdk-type="KotlinSDK">
+  <component name="ProjectRootManager" version="2" languageLevel="JDK_11" project-jdk-name="11" project-jdk-type="JavaSDK">
     <output url="file://$PROJECT_DIR$/out" />
   </component>
 </project>

.idea/modules.xml

@@ -2,16 +2,20 @@
 <project version="4">
   <component name="ProjectModuleManager">
     <modules>
-      <module fileurl="file://$PROJECT_DIR$/codeGeneration/codeGeneration.iml" filepath="$PROJECT_DIR$/codeGeneration/codeGeneration.iml" />
+      <module fileurl="file://$PROJECT_DIR$/codeAst/codeAst.iml" filepath="$PROJECT_DIR$/codeAst/codeAst.iml" />
+      <module fileurl="file://$PROJECT_DIR$/codeCore/codeCore.iml" filepath="$PROJECT_DIR$/codeCore/codeCore.iml" />
+      <module fileurl="file://$PROJECT_DIR$/codeGenCpu6502/codeGenCpu6502.iml" filepath="$PROJECT_DIR$/codeGenCpu6502/codeGenCpu6502.iml" />
+      <module fileurl="file://$PROJECT_DIR$/codeGenExperimental/codeGenExperimental.iml" filepath="$PROJECT_DIR$/codeGenExperimental/codeGenExperimental.iml" />
+      <module fileurl="file://$PROJECT_DIR$/codeGenVirtual/codeGenVirtual.iml" filepath="$PROJECT_DIR$/codeGenVirtual/codeGenVirtual.iml" />
       <module fileurl="file://$PROJECT_DIR$/codeOptimizers/codeOptimizers.iml" filepath="$PROJECT_DIR$/codeOptimizers/codeOptimizers.iml" />
       <module fileurl="file://$PROJECT_DIR$/compiler/compiler.iml" filepath="$PROJECT_DIR$/compiler/compiler.iml" />
       <module fileurl="file://$PROJECT_DIR$/compilerAst/compilerAst.iml" filepath="$PROJECT_DIR$/compilerAst/compilerAst.iml" />
-      <module fileurl="file://$PROJECT_DIR$/compilerInterfaces/compilerInterfaces.iml" filepath="$PROJECT_DIR$/compilerInterfaces/compilerInterfaces.iml" />
       <module fileurl="file://$PROJECT_DIR$/dbusCompilerService/dbusCompilerService.iml" filepath="$PROJECT_DIR$/dbusCompilerService/dbusCompilerService.iml" />
       <module fileurl="file://$PROJECT_DIR$/docs/docs.iml" filepath="$PROJECT_DIR$/docs/docs.iml" />
       <module fileurl="file://$PROJECT_DIR$/examples/examples.iml" filepath="$PROJECT_DIR$/examples/examples.iml" />
       <module fileurl="file://$PROJECT_DIR$/httpCompilerService/httpCompilerService.iml" filepath="$PROJECT_DIR$/httpCompilerService/httpCompilerService.iml" />
       <module fileurl="file://$PROJECT_DIR$/parser/parser.iml" filepath="$PROJECT_DIR$/parser/parser.iml" />
+      <module fileurl="file://$PROJECT_DIR$/virtualmachine/virtualmachine.iml" filepath="$PROJECT_DIR$/virtualmachine/virtualmachine.iml" />
     </modules>
   </component>
 </project>

.idea/vcs.xml

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

CompilerDevelopment.md

@@ -12,6 +12,9 @@
 * 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)

LICENSE

@@ -1,6 +1,9 @@
 
 This sofware license is for Prog8 the compiler + associated libraries.
-The software generated by running the compiler is excluded from this.
+
+Any and all outputs generated by the compiler (intermediary
+source code and compiled binary programs) are excluded from that
+and you can do with them whatever you want.
 
 
 

README.md

@@ -37,7 +37,8 @@ What does Prog8 provide?
 - small program boilerplate/compilersupport overhead
 - programs can be run multiple times without reloading because of automatic variable (re)initializations.
 - conditional branches
-- 'when' statement to provide a concise jump table alternative to if/elseif chains
+- ``when`` statement to provide a concise jump table alternative to if/elseif chains
+- ``in`` expression for concise and efficient multi-value/containment check 
 - many built-in functions such as ``sin``, ``cos``, ``rnd``, ``abs``, ``min``, ``max``, ``sqrt``, ``msb``, ``rol``, ``ror``, ``swap``, ``sort`` and ``reverse``
 - various powerful built-in libraries to do I/O, number conversions, graphics and more  
 - convenience abstractions for low level aspects such as ZeroPage handling, program startup, explicit memory addresses
@@ -52,11 +53,12 @@ What does Prog8 provide?
 - breakpoints, that let the Vice emulator drop into the monitor if execution hits them
 - source code labels automatically loaded in Vice emulator so it can show them in disassembly
 
-*Two supported compiler targets* (contributions to improve these or to add support for other machines are welcome!):
+*Multiple supported compiler targets* (contributions to improve these or to add support for other machines are welcome!):
 
-- "c64": Commodore-64  (6510 CPU = almost a 6502)
+- "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)
-- If you only use standard kernal and prog8 library routines, it is possible to compile the *exact same program* for both machines (just change the compiler target flag)!
+- 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)
 
 
 

codeAst/build.gradle

@@ -11,10 +11,21 @@ java {
     }
 }
 
+compileKotlin {
+    kotlinOptions {
+        jvmTarget = javaVersion
+    }
+}
+
+compileTestKotlin {
+    kotlinOptions {
+        jvmTarget = javaVersion
+    }
+}
+
 dependencies {
-    implementation project(':compilerAst')
+    implementation project(':codeCore')
     implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8"
-    // implementation "org.jetbrains.kotlin:kotlin-reflect"
 }
 
 sourceSets {

codeAst/codeAst.iml

@@ -4,12 +4,11 @@
     <exclude-output />
     <content url="file://$MODULE_DIR$">
       <sourceFolder url="file://$MODULE_DIR$/src" isTestSource="false" />
-      <sourceFolder url="file://$MODULE_DIR$/test" isTestSource="true" />
       <excludeFolder url="file://$MODULE_DIR$/build" />
     </content>
-    <orderEntry type="jdk" jdkName="openjdk-11" jdkType="JavaSDK" />
+    <orderEntry type="inheritedJdk" />
     <orderEntry type="sourceFolder" forTests="false" />
     <orderEntry type="library" name="KotlinJavaRuntime" level="project" />
-    <orderEntry type="module" module-name="compilerAst" />
+    <orderEntry type="module" module-name="codeCore" />
   </component>
 </module>

codeAst/src/prog8/code/SymbolTable.kt

@@ -0,0 +1,217 @@
+package prog8.code
+
+import prog8.code.core.*
+
+
+/**
+ * Tree structure containing all symbol definitions in the program
+ * (blocks, subroutines, variables (all types) and labels).
+ */
+class SymbolTable : StNode("", StNodeType.GLOBAL, Position.DUMMY) {
+    fun print() = printIndented(0)
+
+    override fun printProperties() { }
+
+    /**
+     * 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>()
+        fun flatten(node: StNode) {
+            result[node.scopedName] = node
+            node.children.values.forEach { flatten(it) }
+        }
+        children.values.forEach { flatten(it) }
+        result
+    }
+
+    val allVariables: Collection<StStaticVariable> by lazy {
+        val vars = mutableListOf<StStaticVariable>()
+        fun collect(node: StNode) {
+            for(child in node.children) {
+                if(child.value.type== StNodeType.STATICVAR)
+                    vars.add(child.value as StStaticVariable)
+                else
+                    collect(child.value)
+            }
+        }
+        collect(this)
+        vars
+    }
+
+    override fun lookup(scopedName: List<String>) = flat[scopedName]
+}
+
+
+enum class StNodeType {
+    GLOBAL,
+    // MODULE,     // not used with current scoping rules
+    BLOCK,
+    SUBROUTINE,
+    ROMSUB,
+    LABEL,
+    STATICVAR,
+    MEMVAR,
+    CONSTANT,
+    BUILTINFUNC
+}
+
+
+open class StNode(val name: String,
+                  val type: StNodeType,
+                  val position: Position,
+                  val children: MutableMap<String, StNode> = mutableMapOf()
+) {
+
+    lateinit var parent: StNode
+
+    val scopedName: List<String> by lazy {
+        if(type== StNodeType.GLOBAL)
+            emptyList()
+        else
+            parent.scopedName + name
+    }
+
+    fun lookup(name: String) =
+        lookupUnqualified(name)
+    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? {
+        // 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
+    }
+
+    private fun lookupUnqualified(name: String): StNode? {
+        // first consider the builtin functions
+        var globalscope = this
+        while(globalscope.type!= StNodeType.GLOBAL)
+            globalscope = globalscope.parent
+        val globalNode = globalscope.children[name]
+        if(globalNode!=null && globalNode.type== StNodeType.BUILTINFUNC)
+            return globalNode
+
+        // search for the unqualified name in the current scope or its parent scopes
+        var scope=this
+        while(true) {
+            val node = scope.children[name]
+            if(node!=null)
+                return node
+            if(scope.type== StNodeType.GLOBAL)
+                return null
+            else
+                scope = scope.parent
+        }
+    }
+
+    fun printIndented(indent: Int) {
+        print("    ".repeat(indent))
+        when(type) {
+            StNodeType.GLOBAL -> print("SYMBOL-TABLE:")
+            StNodeType.BLOCK -> print("(B) ")
+            StNodeType.SUBROUTINE -> print("(S) ")
+            StNodeType.LABEL -> print("(L) ")
+            StNodeType.STATICVAR -> print("(V) ")
+            StNodeType.MEMVAR -> print("(M) ")
+            StNodeType.CONSTANT -> print("(C) ")
+            StNodeType.BUILTINFUNC -> print("(F) ")
+            StNodeType.ROMSUB -> print("(R) ")
+        }
+        printProperties()
+        println()
+        children.forEach { (_, node) -> node.printIndented(indent+1) }
+    }
+
+    open fun printProperties() {
+        print("$name  ")
+    }
+
+    fun add(child: StNode) {
+        children[child.name] = child
+        child.parent = this
+    }
+}
+
+class StStaticVariable(name: String,
+                       val dt: DataType,
+                       val initialNumericValue: Double?,
+                       val initialStringValue: StString?,
+                       val initialArrayValue: StArray?,
+                       val length: Int?,             // for arrays: the number of elements, for strings: number of characters *including* the terminating 0-byte
+                       val zpwish: ZeropageWish,
+                       position: Position) : StNode(name, StNodeType.STATICVAR, position) {
+
+    init {
+        if(length!=null) {
+            require(initialNumericValue == null)
+            if(initialArrayValue!=null)
+                require(length == initialArrayValue.size)
+        }
+        if(initialNumericValue!=null)
+            require(dt in NumericDatatypes)
+        if(initialArrayValue!=null)
+            require(dt in ArrayDatatypes)
+        if(initialStringValue!=null) {
+            require(dt == DataType.STR)
+            require(length == initialStringValue.first.length+1)
+        }
+    }
+
+    override fun printProperties() {
+        print("$name  dt=$dt  zpw=$zpwish")
+    }
+}
+
+
+class StConstant(name: String, val dt: DataType, val value: Double, position: Position) :
+    StNode(name, StNodeType.CONSTANT, position) {
+    override fun printProperties() {
+        print("$name  dt=$dt value=$value")
+    }
+}
+
+
+class StMemVar(name: String, val dt: DataType, val address: UInt, position: Position) :
+    StNode(name, StNodeType.MEMVAR, position) {
+    override fun printProperties() {
+        print("$name  dt=$dt address=${address.toHex()}")
+    }
+}
+
+
+class StSub(name: String, val parameters: List<StSubroutineParameter>, position: Position) :
+        StNode(name, StNodeType.SUBROUTINE, position) {
+    override fun printProperties() {
+        print(name)
+    }
+}
+
+
+class StRomSub(name: String, val address: UInt, parameters: List<StSubroutineParameter>, position: Position) :
+    StNode(name, StNodeType.ROMSUB, position) {
+    override fun printProperties() {
+        print("$name  address=${address.toHex()}")
+    }
+}
+
+
+class StSubroutineParameter(val name: String, val type: DataType)
+class StArrayElement(val number: Double?, val addressOf: List<String>?)
+
+typealias StString = Pair<String, Encoding>
+typealias StArray = List<StArrayElement>

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

@@ -0,0 +1,144 @@
+package prog8.code.ast
+
+import prog8.code.core.*
+import java.nio.file.Path
+
+// New (work-in-progress) simplified AST for the code generator.
+
+
+sealed class PtNode(val position: Position) {
+
+    val children = mutableListOf<PtNode>()
+    lateinit var parent: PtNode
+
+    fun printIndented(indent: Int) {
+        print("    ".repeat(indent))
+        print("${this.javaClass.simpleName}  ")
+        printProperties()
+        println()
+        children.forEach { it.printIndented(indent+1) }
+    }
+
+    abstract fun printProperties()
+
+    fun add(child: PtNode) {
+        children.add(child)
+        child.parent = this
+    }
+
+    fun add(index: Int, child: PtNode) {
+        children.add(index, child)
+        child.parent = this
+    }
+
+    fun definingBlock() = findParentNode<PtBlock>(this)
+    fun definingSub() = findParentNode<PtSub>(this)
+    fun definingAsmSub() = findParentNode<PtAsmSub>(this)
+}
+
+
+class PtNodeGroup : PtNode(Position.DUMMY) {
+    override fun printProperties() {}
+}
+
+
+abstract class PtNamedNode(val name: String, position: Position): PtNode(position) {
+    val scopedName: List<String> by lazy {
+        var namedParent: PtNode = this.parent
+        if(namedParent is PtProgram)
+            listOf(name)
+        else {
+            while (namedParent !is PtNamedNode)
+                namedParent = namedParent.parent
+            namedParent.scopedName + name
+        }
+    }
+}
+
+
+class PtProgram(
+    val name: String,
+    val memsizer: IMemSizer,
+    val encoding: IStringEncoding
+) : PtNode(Position.DUMMY) {
+    fun print() = printIndented(0)
+    override fun printProperties() {
+        print("'$name'")
+    }
+
+//    fun allModuleDirectives(): Sequence<PtDirective> =
+//        children.asSequence().flatMap { it.children }.filterIsInstance<PtDirective>().distinct()
+
+    fun allBlocks(): Sequence<PtBlock> =
+        children.asSequence().filterIsInstance<PtBlock>()
+
+    fun entrypoint(): PtSub? =
+        allBlocks().firstOrNull { it.name == "main" }?.children?.firstOrNull { it is PtSub && it.name == "start" } as PtSub?
+}
+
+
+class PtBlock(name: String,
+              val address: UInt?,
+              val library: Boolean,
+              val forceOutput: Boolean,
+              val alignment: BlockAlignment,
+              position: Position
+) : PtNamedNode(name, position) {
+    override fun printProperties() {
+        print("$name  addr=$address  library=$library  forceOutput=$forceOutput  alignment=$alignment")
+    }
+
+    enum class BlockAlignment {
+        NONE,
+        WORD,
+        PAGE
+    }
+}
+
+
+class PtInlineAssembly(val assembly: String, position: Position) : PtNode(position) {
+    override fun printProperties() {}
+}
+
+
+class PtLabel(name: String, position: Position) : PtNamedNode(name, position) {
+    override fun printProperties() {
+        print(name)
+    }
+}
+
+
+class PtBreakpoint(position: Position): PtNode(position) {
+    override fun printProperties() {}
+}
+
+
+class PtIncludeBinary(val file: Path, val offset: UInt?, val length: UInt?, position: Position) : PtNode(position) {
+    override fun printProperties() {
+        print("filename=$file  offset=$offset  length=$length")
+    }
+}
+
+
+class PtNop(position: Position): PtNode(position) {
+    override fun printProperties() {}
+}
+
+
+class PtScopeVarsDecls(position: Position): PtNode(position) {
+    override fun printProperties() {}
+}
+
+
+
+// find the parent node of a specific type or interface
+// (useful to figure out in what namespace/block something is defined, etc.)
+inline fun <reified T> findParentNode(node: PtNode): T? {
+    var candidate = node.parent
+    while(candidate !is T && candidate !is PtProgram)
+        candidate = candidate.parent
+    return if(candidate is PtProgram)
+        null
+    else
+        candidate as T
+}

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

@@ -0,0 +1,216 @@
+package prog8.code.ast
+
+import prog8.code.core.DataType
+import prog8.code.core.Encoding
+import prog8.code.core.Position
+import java.util.*
+import kotlin.math.round
+
+
+sealed class PtExpression(val type: DataType, position: Position) : PtNode(position) {
+    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 PtArrayIndexer -> other is PtArrayIndexer && other.type==type && other.variable isSameAs variable && other.index isSameAs index
+            is PtBinaryExpression -> other is PtBinaryExpression && other.left isSameAs left && other.right isSameAs right
+            is PtContainmentCheck -> other is PtContainmentCheck && other.type==type && other.element isSameAs element && other.iterable isSameAs iterable
+            is PtIdentifier -> other is PtIdentifier && other.type==type && other.targetName==targetName
+            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
+            is PtPrefix -> other is PtPrefix && other.type==type && other.operator==operator && other.value isSameAs value
+            is PtRange -> other is PtRange && other.type==type && other.from==from && other.to==to && other.step==step
+            is PtTypeCast -> other is PtTypeCast && other.type==type && other.value isSameAs value
+            else -> false
+        }
+    }
+}
+
+class PtAddressOf(position: Position) : PtExpression(DataType.UWORD, position) {
+    val identifier: PtIdentifier
+        get() = children.single() as PtIdentifier
+}
+
+
+class PtArrayIndexer(type: DataType, position: Position): PtExpression(type, position) {
+    val variable: PtIdentifier
+        get() = children[0] as PtIdentifier
+    val index: PtExpression
+        get() = children[1] as PtExpression
+}
+
+
+class PtArray(type: DataType, position: Position): PtExpression(type, position) {
+    override fun hashCode(): Int = Objects.hash(children, type)
+    override fun equals(other: Any?): Boolean {
+        if(other==null || other !is PtArray)
+            return false
+        return type==other.type && children == other.children
+    }
+}
+
+
+class PtBuiltinFunctionCall(val name: String,
+                            val void: Boolean,
+                            val hasNoSideEffects: Boolean,
+                            type: DataType,
+                            position: Position) : PtExpression(type, position) {
+    init {
+        if(!void)
+            require(type!=DataType.UNDEFINED)
+    }
+
+    val args: List<PtExpression>
+        get() = children.map { it as PtExpression }
+    override fun printProperties() {
+        print("$name void=$void noSideFx=$hasNoSideEffects")
+    }
+}
+
+
+class PtBinaryExpression(val operator: String, type: DataType, position: Position): PtExpression(type, position) {
+    val left: PtExpression
+        get() = children[0] as PtExpression
+    val right: PtExpression
+        get() = children[1] as PtExpression
+
+    override fun printProperties() {
+        print("$operator -> $type")
+    }
+}
+
+
+class PtContainmentCheck(position: Position): PtExpression(DataType.UBYTE, position) {
+    val element: PtExpression
+        get() = children[0] as PtExpression
+    val iterable: PtIdentifier
+        get() = children[1] as PtIdentifier
+}
+
+
+class PtFunctionCall(val functionName: List<String>,
+                     val void: Boolean,
+                     type: DataType,
+                     position: Position) : PtExpression(type, position) {
+    init {
+        if(!void)
+            require(type!=DataType.UNDEFINED)
+    }
+
+    val args: List<PtExpression>
+        get() = children.map { it as PtExpression }
+    override fun printProperties() {
+        print("${functionName.joinToString(".")} void=$void")
+    }
+}
+
+
+class PtIdentifier(val ref: List<String>, val targetName: List<String>, type: DataType, position: Position) : PtExpression(type, position) {
+    override fun printProperties() {
+        print("$ref --> $targetName  $type")
+    }
+}
+
+
+class PtMemoryByte(position: Position) : PtExpression(DataType.UBYTE, position) {
+    val address: PtExpression
+        get() = children.single() as PtExpression
+    override fun printProperties() {}
+}
+
+
+class PtNumber(type: DataType, val number: Double, position: Position) : PtExpression(type, position) {
+
+    init {
+        if(type!=DataType.FLOAT) {
+            val rounded = round(number)
+            if (rounded != number)
+                throw IllegalArgumentException("refused rounding of float to avoid loss of precision")
+        }
+    }
+
+    override fun printProperties() {
+        print("$number ($type)")
+    }
+
+    override fun hashCode(): Int = Objects.hash(type, number)
+
+    override fun equals(other: Any?): Boolean {
+        if(other==null || other !is PtNumber)
+            return false
+        return number==other.number
+    }
+
+    operator fun compareTo(other: PtNumber): Int = number.compareTo(other.number)
+}
+
+
+class PtPipe(type: DataType, val void: Boolean, position: Position) : PtExpression(type, position) {
+    init {
+        if(!void)
+            require(type!=DataType.UNDEFINED)
+    }
+
+    val segments: List<PtExpression>
+        get() = children.map { it as PtExpression }
+
+    override fun printProperties() {}
+}
+
+
+class PtPrefix(val operator: String, type: DataType, position: Position): PtExpression(type, position) {
+    val value: PtExpression
+        get() = children.single() as PtExpression
+
+    override fun printProperties() {
+        print(operator)
+    }
+}
+
+
+class PtRange(type: DataType, position: Position) : PtExpression(type, position) {
+    val from: PtExpression
+        get() = children[0] as PtExpression
+    val to: PtExpression
+        get() = children[1] as PtExpression
+    val step: PtNumber
+        get() = children[2] as PtNumber
+
+    override fun printProperties() {}
+}
+
+
+class PtString(val value: String, val encoding: Encoding, position: Position) : PtExpression(DataType.STR, position) {
+    override fun printProperties() {
+        print("$encoding:\"$value\"")
+    }
+
+    override fun hashCode(): Int = Objects.hash(value, encoding)
+    override fun equals(other: Any?): Boolean {
+        if(other==null || other !is PtString)
+            return false
+        return value==other.value && encoding == other.encoding
+    }
+}
+
+
+class PtTypeCast(type: DataType, position: Position) : PtExpression(type, position) {
+    val value: PtExpression
+        get() = children.single() as PtExpression
+}
+
+
+// special node that isn't created from compiling user code, but used internally
+class PtMachineRegister(val register: Int, type: DataType, position: Position) : PtExpression(type, position) {
+    override fun printProperties() {
+        print("reg=$register  $type")
+    }
+}
+
+
+fun constValue(expr: PtExpression): Double? = if(expr is PtNumber) expr.number else null
+fun constIntValue(expr: PtExpression): Int? = if(expr is PtNumber) expr.number.toInt() else null

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

@@ -0,0 +1,219 @@
+package prog8.code.ast
+
+import prog8.code.core.*
+
+
+class PtAsmSub(
+    name: String,
+    val address: UInt?,
+    val clobbers: Set<CpuRegister>,
+    val parameters: List<Pair<PtSubroutineParameter, RegisterOrStatusflag>>,
+    val retvalRegisters: List<RegisterOrStatusflag>,
+    val inline: Boolean,
+    position: Position
+) : PtNamedNode(name, position) {
+    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) {
+    override fun printProperties() {
+        print(name)
+    }
+}
+
+
+class PtSubroutineParameter(val name: String, val type: DataType, position: Position): PtNode(position) {
+    override fun printProperties() {
+        print("$type $name")
+    }
+}
+
+
+class PtAssignment(position: Position) : PtNode(position) {
+    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 PtAssignTarget(position: Position) : PtNode(position) {
+    val identifier: PtIdentifier?
+        get() = children.single() as? PtIdentifier
+    val array: PtArrayIndexer?
+        get() = children.single() as? PtArrayIndexer
+    val memory: PtMemoryByte?
+        get() = children.single() as? PtMemoryByte
+
+    val type: DataType
+        get() {
+            return when(val tgt = children.single()) {
+                is PtIdentifier -> tgt.type
+                is PtArrayIndexer -> tgt.type
+                is PtMemoryByte -> tgt.type
+                else -> throw AssemblyError("weird target $tgt")
+            }
+        }
+
+    override fun printProperties() {}
+}
+
+
+class PtConditionalBranch(val condition: BranchCondition, position: Position) : PtNode(position) {
+    val trueScope: PtNodeGroup
+        get() = children[0] as PtNodeGroup
+    val falseScope: PtNodeGroup
+        get() = children[1] as PtNodeGroup
+
+    override fun printProperties() {
+        print(condition)
+    }
+}
+
+
+class PtForLoop(position: Position) : PtNode(position) {
+    val variable: PtIdentifier
+        get() = children[0] as PtIdentifier
+    val iterable: PtExpression
+        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
+        get() = children[0] as PtBinaryExpression
+    val ifScope: PtNodeGroup
+        get() = children[1] as PtNodeGroup
+    val elseScope: PtNodeGroup
+        get() = children[2] as PtNodeGroup
+
+    override fun printProperties() {}
+}
+
+
+class PtJump(val identifier: PtIdentifier?,
+             val address: UInt?,
+             val generatedLabel: String?,
+             position: Position) : PtNode(position) {
+    override fun printProperties() {
+        identifier?.printProperties()
+        if(address!=null) print(address.toHex())
+        if(generatedLabel!=null) print(generatedLabel)
+    }
+}
+
+
+class PtPostIncrDecr(val operator: String, position: Position) : PtNode(position) {
+    val target: PtAssignTarget
+        get() = children.single() as PtAssignTarget
+
+    override fun printProperties() {
+        print(operator)
+    }
+}
+
+
+class PtRepeatLoop(position: Position) : PtNode(position) {
+    val count: PtExpression
+        get() = children[0] as PtExpression
+    val statements: PtNodeGroup
+        get() = children[1] as PtNodeGroup
+
+    override fun printProperties() {}
+}
+
+
+class PtReturn(position: Position) : PtNode(position) {
+    val hasValue = children.any()
+    val value: PtExpression?
+        get() {
+            return if(children.any())
+                children.single() as PtExpression
+            else
+                null
+        }
+
+    override fun printProperties() {}
+}
+
+
+class PtVariable(name: String, val type: DataType, var value: PtExpression?, var arraySize: UInt?, position: Position) : PtNamedNode(name, position) {
+    override fun printProperties() {
+        print("$type  $name")
+    }
+}
+
+
+class PtConstant(name: String, val type: DataType, val value: Double, position: Position) : PtNamedNode(name, position) {
+    override fun printProperties() {
+        print("$type $name = $value")
+    }
+}
+
+
+class PtMemMapped(name: String, val type: DataType, val address: UInt, position: Position) : PtNamedNode(name, position) {
+    override fun printProperties() {
+        print("&$type $name = ${address.toHex()}")
+    }
+}
+
+
+class PtWhen(position: Position) : PtNode(position) {
+    val value: PtExpression
+        get() = children[0] as PtExpression
+    val choices: PtNodeGroup
+        get() = children[1] as PtNodeGroup
+
+    override fun printProperties() {}
+}
+
+
+class PtWhenChoice(val isElse: Boolean, position: Position) : PtNode(position) {
+    val values: PtNodeGroup
+        get() = children[0] as PtNodeGroup
+    val statements: PtNodeGroup
+        get() = children[1] as PtNodeGroup
+    override fun printProperties() {}
+}

codeCore/build.gradle

@@ -0,0 +1,43 @@
+
+plugins {
+    id 'java'
+    id 'application'
+    id "org.jetbrains.kotlin.jvm"
+}
+
+java {
+    toolchain {
+        languageVersion = JavaLanguageVersion.of(javaVersion)
+    }
+}
+
+compileKotlin {
+    kotlinOptions {
+        jvmTarget = javaVersion
+    }
+}
+
+compileTestKotlin {
+    kotlinOptions {
+        jvmTarget = javaVersion
+    }
+}
+
+dependencies {
+    // should have no dependencies to other modules
+    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8"
+    implementation "com.michael-bull.kotlin-result:kotlin-result-jvm:1.1.14"
+}
+
+sourceSets {
+    main {
+        java {
+            srcDirs = ["${project.projectDir}/src"]
+        }
+        resources {
+            srcDirs = ["${project.projectDir}/res"]
+        }
+    }
+}
+
+// note: there are no unit tests in this module!

codeCore/codeCore.iml

@@ -0,0 +1,14 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<module type="JAVA_MODULE" version="4">
+  <component name="NewModuleRootManager" inherit-compiler-output="true">
+    <exclude-output />
+    <content url="file://$MODULE_DIR$">
+      <sourceFolder url="file://$MODULE_DIR$/src" isTestSource="false" />
+      <excludeFolder url="file://$MODULE_DIR$/build" />
+    </content>
+    <orderEntry type="inheritedJdk" />
+    <orderEntry type="sourceFolder" forTests="false" />
+    <orderEntry type="library" name="KotlinJavaRuntime" level="project" />
+    <orderEntry type="library" name="michael.bull.kotlin.result.jvm" level="project" />
+  </component>
+</module>

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

@@ -0,0 +1,24 @@
+package prog8.code.core
+
+import java.nio.file.Path
+import kotlin.io.path.Path
+
+
+class CompilationOptions(val output: OutputType,
+                         val launcher: CbmPrgLauncherType,
+                         val zeropage: ZeropageType,
+                         val zpReserved: List<UIntRange>,
+                         val 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 optimize: Boolean = false,
+                         var optimizeFloatExpressions: Boolean = false,
+                         var dontReinitGlobals: Boolean = false,
+                         var asmQuiet: Boolean = false,
+                         var asmListfile: Boolean = false,
+                         var experimentalCodegen: Boolean = false,
+                         var outputDir: Path = Path("")
+)

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

@@ -0,0 +1,89 @@
+package prog8.code.core
+
+import kotlin.math.abs
+
+fun Number.toHex(): String {
+    //  0..15 -> "0".."15"
+    //  16..255 -> "$10".."$ff"
+    //  256..65536 -> "$0100".."$ffff"
+    // negative values are prefixed with '-'.
+    val integer = this.toInt()
+    if(integer<0)
+        return '-' + abs(integer).toHex()
+    return when (integer) {
+        in 0 until 16 -> integer.toString()
+        in 0 until 0x100 -> "$"+integer.toString(16).padStart(2,'0')
+        in 0 until 0x10000 -> "$"+integer.toString(16).padStart(4,'0')
+        else -> throw IllegalArgumentException("number too large for 16 bits $this")
+    }
+}
+
+fun UInt.toHex(): String {
+    //  0..15 -> "0".."15"
+    //  16..255 -> "$10".."$ff"
+    //  256..65536 -> "$0100".."$ffff"
+    return when (this) {
+        in 0u until 16u -> this.toString()
+        in 0u until 0x100u -> "$"+this.toString(16).padStart(2,'0')
+        in 0u until 0x10000u -> "$"+this.toString(16).padStart(4,'0')
+        else -> throw IllegalArgumentException("number too large for 16 bits $this")
+    }
+}
+
+fun Char.escape(): Char = this.toString().escape()[0]
+
+fun String.escape(): String {
+    val es = this.map {
+        when(it) {
+            '\t' -> "\\t"
+            '\n' -> "\\n"
+            '\r' -> "\\r"
+            '"' -> "\\\""
+            in '\u8000'..'\u80ff' -> "\\x" + (it.code - 0x8000).toString(16).padStart(2, '0')       // 'ugly' passthrough hack
+            in '\u0000'..'\u00ff' -> it.toString()
+            else -> "\\u" + it.code.toString(16).padStart(4, '0')
+        }
+    }
+    return es.joinToString("")
+}
+
+fun String.unescape(): String {
+    val result = mutableListOf<Char>()
+    val iter = this.iterator()
+    while(iter.hasNext()) {
+        val c = iter.nextChar()
+        if(c=='\\') {
+            val ec = iter.nextChar()
+            result.add(when(ec) {
+                '\\' -> '\\'
+                'n' -> '\n'
+                'r' -> '\r'
+                '"' -> '"'
+                '\'' -> '\''
+                'u' -> {
+                    try {
+                        "${iter.nextChar()}${iter.nextChar()}${iter.nextChar()}${iter.nextChar()}".toInt(16).toChar()
+                    } catch (sb: StringIndexOutOfBoundsException) {
+                        throw IllegalArgumentException("invalid \\u escape sequence")
+                    } catch (nf: NumberFormatException) {
+                        throw IllegalArgumentException("invalid \\u escape sequence")
+                    }
+                }
+                'x' -> {
+                    try {
+                        val hex = ("" + iter.nextChar() + iter.nextChar()).toInt(16)
+                        (0x8000 + hex).toChar()         // 'ugly' pass-through hack
+                    } catch (sb: StringIndexOutOfBoundsException) {
+                        throw IllegalArgumentException("invalid \\x escape sequence")
+                    } catch (nf: NumberFormatException) {
+                        throw IllegalArgumentException("invalid \\x escape sequence")
+                    }
+                }
+                else -> throw IllegalArgumentException("invalid escape char in string: \\$ec")
+            })
+        } else {
+            result.add(c)
+        }
+    }
+    return result.joinToString("")
+}

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

@@ -0,0 +1,182 @@
+package prog8.code.core
+
+enum class DataType {
+    UBYTE,              // pass by value
+    BYTE,               // pass by value
+    UWORD,              // pass by value
+    WORD,               // pass by value
+    FLOAT,              // pass by value
+    STR,                // pass by reference
+    ARRAY_UB,           // pass by reference
+    ARRAY_B,            // pass by reference
+    ARRAY_UW,           // pass by reference
+    ARRAY_W,            // pass by reference
+    ARRAY_F,            // pass by reference
+    UNDEFINED;
+
+    /**
+     * is the type assignable to the given other type (perhaps via a typecast) without loss of precision?
+     */
+    infix fun isAssignableTo(targetType: DataType) =
+        when(this) {
+            UBYTE -> targetType.oneOf(UBYTE, WORD, UWORD, FLOAT)
+            BYTE -> targetType.oneOf(BYTE, WORD, FLOAT)
+            UWORD -> targetType.oneOf(UWORD, FLOAT)
+            WORD -> targetType.oneOf(WORD, FLOAT)
+            FLOAT -> targetType == FLOAT
+            STR -> targetType.oneOf(STR, UWORD)
+            in ArrayDatatypes -> targetType == this
+            else -> false
+        }
+
+    fun oneOf(vararg types: DataType) = this in types
+
+    infix fun largerThan(other: DataType) =
+        when {
+            this == other -> false
+            this in ByteDatatypes -> false
+            this in WordDatatypes -> other in ByteDatatypes
+            this== STR && other== UWORD || this== UWORD && other== STR -> false
+            else -> true
+        }
+
+    infix fun equalsSize(other: DataType) =
+        when {
+            this == other -> true
+            this in ByteDatatypes -> other in ByteDatatypes
+            this in WordDatatypes -> other in WordDatatypes
+            this== STR && other== UWORD || this== UWORD && other== STR -> true
+            else -> false
+        }
+}
+
+enum class CpuRegister {
+    A,
+    X,
+    Y;
+
+    fun asRegisterOrPair(): RegisterOrPair = when(this) {
+        A -> RegisterOrPair.A
+        X -> RegisterOrPair.X
+        Y -> RegisterOrPair.Y
+    }
+}
+
+enum class RegisterOrPair {
+    A,
+    X,
+    Y,
+    AX,
+    AY,
+    XY,
+    FAC1,
+    FAC2,
+    // cx16 virtual registers:
+    R0, R1, R2, R3, R4, R5, R6, R7,
+    R8, R9, R10, R11, R12, R13, R14, R15;
+
+    companion object {
+        val names by lazy { values().map { it.toString()} }
+    }
+
+    fun asCpuRegister(): CpuRegister = when(this) {
+        A -> CpuRegister.A
+        X -> CpuRegister.X
+        Y -> CpuRegister.Y
+        else -> throw IllegalArgumentException("no cpu hardware register for $this")
+    }
+
+}       // only used in parameter and return value specs in asm subroutines
+
+enum class Statusflag {
+    Pc,
+    Pz,     // don't use
+    Pv,
+    Pn;     // don't use
+
+    companion object {
+        val names by lazy { values().map { it.toString()} }
+    }
+}
+
+enum class BranchCondition {
+    CS,
+    CC,
+    EQ,     // EQ == Z
+    Z,
+    NE,     // NE == NZ
+    NZ,
+    MI,     // MI == NEG
+    NEG,
+    PL,     // PL == POS
+    POS,
+    VS,
+    VC,
+}
+
+
+val ByteDatatypes = arrayOf(DataType.UBYTE, DataType.BYTE)
+val WordDatatypes = arrayOf(DataType.UWORD, DataType.WORD)
+val IntegerDatatypes = arrayOf(DataType.UBYTE, DataType.BYTE, DataType.UWORD, DataType.WORD)
+val NumericDatatypes = arrayOf(DataType.UBYTE, DataType.BYTE, DataType.UWORD, DataType.WORD, DataType.FLOAT)
+val SignedDatatypes =  arrayOf(DataType.BYTE, DataType.WORD, DataType.FLOAT)
+val IntegerArrayDatatypes = arrayOf(DataType.ARRAY_UB, DataType.ARRAY_B, DataType.ARRAY_UW, DataType.ARRAY_W)
+val ArrayDatatypes = arrayOf(DataType.ARRAY_UB, DataType.ARRAY_B, DataType.ARRAY_UW, DataType.ARRAY_W, DataType.ARRAY_F)
+val StringlyDatatypes = arrayOf(DataType.STR, DataType.ARRAY_UB, DataType.ARRAY_B, DataType.UWORD)
+val IterableDatatypes = arrayOf(
+    DataType.STR,
+    DataType.ARRAY_UB, DataType.ARRAY_B,
+    DataType.ARRAY_UW, DataType.ARRAY_W,
+    DataType.ARRAY_F
+)
+val PassByValueDatatypes = NumericDatatypes
+val PassByReferenceDatatypes = IterableDatatypes
+val ArrayToElementTypes = mapOf(
+    DataType.STR to DataType.UBYTE,
+    DataType.ARRAY_B to DataType.BYTE,
+    DataType.ARRAY_UB to DataType.UBYTE,
+    DataType.ARRAY_W to DataType.WORD,
+    DataType.ARRAY_UW to DataType.UWORD,
+    DataType.ARRAY_F to DataType.FLOAT
+)
+val ElementToArrayTypes = mapOf(
+    DataType.BYTE to DataType.ARRAY_B,
+    DataType.UBYTE to DataType.ARRAY_UB,
+    DataType.WORD to DataType.ARRAY_W,
+    DataType.UWORD to DataType.ARRAY_UW,
+    DataType.FLOAT to DataType.ARRAY_F
+)
+val Cx16VirtualRegisters = arrayOf(
+    RegisterOrPair.R0, RegisterOrPair.R1, RegisterOrPair.R2, RegisterOrPair.R3,
+    RegisterOrPair.R4, RegisterOrPair.R5, RegisterOrPair.R6, RegisterOrPair.R7,
+    RegisterOrPair.R8, RegisterOrPair.R9, RegisterOrPair.R10, RegisterOrPair.R11,
+    RegisterOrPair.R12, RegisterOrPair.R13, RegisterOrPair.R14, RegisterOrPair.R15
+)
+
+
+
+enum class OutputType {
+    RAW,
+    PRG,
+    XEX
+}
+
+enum class CbmPrgLauncherType {
+    BASIC,
+    NONE
+}
+
+enum class ZeropageType {
+    BASICSAFE,
+    FLOATSAFE,
+    KERNALSAFE,
+    FULL,
+    DONTUSE
+}
+
+enum class ZeropageWish {
+    REQUIRE_ZEROPAGE,
+    PREFER_ZEROPAGE,
+    DONTCARE,
+    NOT_IN_ZEROPAGE
+}

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

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

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

@@ -0,0 +1,12 @@
+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/ICompilationTarget.kt

@@ -0,0 +1,11 @@
+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
+}

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

@@ -1,7 +1,4 @@
-package prog8.compilerinterface
-
-import prog8.ast.base.Position
-
+package prog8.code.core
 
 interface IErrorReporter {
     fun err(msg: String, position: Position)
@@ -10,7 +7,6 @@ interface IErrorReporter {
     fun report()
     fun finalizeNumErrors(numErrors: Int, numWarnings: Int) {
         if(numErrors>0)
-            throw AbortCompilation("There are $numErrors errors and $numWarnings warnings.")
+            throw ErrorsReportedException("There are $numErrors errors and $numWarnings warnings.")
     }
 }
-

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

@@ -1,4 +1,4 @@
-package prog8.compilerinterface
+package prog8.code.core
 
 import java.nio.file.Path
 
@@ -10,18 +10,17 @@ interface IMachineFloat {
 
 enum class CpuType {
     CPU6502,
-    CPU65c02
+    CPU65c02,
+    VIRTUAL
 }
 
 interface IMachineDefinition {
     val FLOAT_MAX_NEGATIVE: Double
     val FLOAT_MAX_POSITIVE: Double
     val FLOAT_MEM_SIZE: Int
-    val POINTER_MEM_SIZE: Int
     val ESTACK_LO: UInt
     val ESTACK_HI: UInt
-    val BASIC_LOAD_ADDRESS : UInt
-    val RAW_LOAD_ADDRESS : UInt
+    val PROGRAM_LOAD_ADDRESS : UInt
 
     val opcodeNames: Set<String>
     var zeropage: Zeropage

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

@@ -0,0 +1,6 @@
+package prog8.code.core
+
+interface IMemSizer {
+    fun memorySize(dt: DataType): Int
+    fun memorySize(arrayDt: DataType, numElements: Int): Int
+}

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

@@ -0,0 +1,14 @@
+package prog8.code.core
+
+enum class Encoding(val prefix: String) {
+    DEFAULT("default"),         // depends on compilation target
+    PETSCII("petscii"),         // c64/c128/cx16
+    SCREENCODES("sc"),          // c64/c128/cx16
+    ATASCII("atascii"),         // atari
+    ISO("iso")                  // cx16
+}
+
+interface IStringEncoding {
+    fun encodeString(str: String, encoding: Encoding): List<UByte>
+    fun decodeString(bytes: List<UByte>, encoding: Encoding): String
+}

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

@@ -0,0 +1,18 @@
+package prog8.code.core
+
+val AssociativeOperators = setOf("+", "*", "&", "|", "^", "or", "and", "xor", "==", "!=")
+val ComparisonOperators = setOf("==", "!=", "<", ">", "<=", ">=")
+val AugmentAssignmentOperators = setOf("+", "-", "/", "*", "&", "|", "^", "<<", ">>", "%", "and", "or", "xor")
+val LogicalOperators = setOf("and", "or", "xor", "not")
+val BitwiseOperators = setOf("&", "|", "^")
+
+fun invertedComparisonOperator(operator: String) =
+    when (operator) {
+        "==" -> "!="
+        "!=" -> "=="
+        "<" -> ">="
+        ">" -> "<="
+        "<=" -> ">"
+        ">=" -> "<"
+        else -> null
+    }

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

@@ -0,0 +1,16 @@
+package prog8.code.core
+
+import kotlin.io.path.Path
+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 {
+        val path = Path(file).absolute().normalize()
+        return "file://$path:$line:$startCol:"
+    }
+
+    companion object {
+        val DUMMY = Position("<dummy>", 0, 0, 0)
+    }
+}

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

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

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

@@ -1,27 +1,20 @@
-package prog8.parser
+package prog8.code.core
 
-import org.antlr.v4.runtime.CharStream
-import org.antlr.v4.runtime.CharStreams
 import java.io.File
 import java.io.IOException
-import java.nio.channels.Channels
-import java.nio.charset.CodingErrorAction
-import java.nio.charset.StandardCharsets
 import java.nio.file.Path
-import kotlin.io.path.*
+import kotlin.io.path.Path
+import kotlin.io.path.readText
+
+
+const val internedStringsModuleName = "prog8_interned_strings"
+
 
 /**
- * Encapsulates - and ties together - actual source code (=text)
- * and its [origin].
+ * Encapsulates - and ties together - actual source code (=text) and its [origin].
  */
 sealed class SourceCode {
 
-    /**
-     * To be used *only* by the parser (as input to a TokenStream).
-     * DO NOT mess around with!
-     */
-    internal abstract fun getCharStream(): CharStream
-
     /**
      * Whether this [SourceCode] instance was created as a [Resource]
      */
@@ -32,6 +25,11 @@ sealed class SourceCode {
      */
     abstract val isFromFilesystem: Boolean
 
+    /**
+     * The logical name of the source code unit. Usually the module's name.
+     */
+    abstract val name: String
+
     /**
      * Where this [SourceCode] instance came from.
      * This can be one of the following:
@@ -44,11 +42,10 @@ sealed class SourceCode {
     /**
      * The source code as plain string.
      */
-    abstract fun readText(): String
+    abstract val text: String
 
     /**
-     * Deliberately does NOT return the actual text.
-     * For this - if at all - use [getCharStream].
+     * Printable representation, deliberately does NOT return the actual text.
      */
     final override fun toString() = "${this.javaClass.name}[${this.origin}]"
 
@@ -69,43 +66,40 @@ sealed class SourceCode {
      * Turn a plain String into a [SourceCode] object.
      * [origin] will be something like `$stringSourcePrefix44c56085>`.
      */
-    class Text(val text: String): SourceCode() {
+    class Text(override val text: String): SourceCode() {
         override val isFromResources = false
         override val isFromFilesystem = false
         override val origin = "$stringSourcePrefix${System.identityHashCode(text).toString(16)}>"
-        override fun getCharStream(): CharStream = CharStreams.fromString(text, origin)
-        override fun readText() = text
+        override val name = "<unnamed-text>"
     }
 
     /**
      * Get [SourceCode] from the file represented by the specified Path.
-     * This does not actually *access* the file, but it does check
-     * whether it
-     * * exists
-     * * is a regular file (ie: not a directory)
-     * * and is actually readable
+     * This immediately reads the file fully into memory.
      *
      * [origin] will be the given path in absolute and normalized form.
      * @throws NoSuchFileException if the file does not exist
-     * @throws AccessDeniedException if the given path points to a directory or the file is non-readable for some other reason
+     * @throws FileSystemException if the file cannot be read
      */
     class File(path: Path): SourceCode() {
-        private val normalized = path.normalize()
-        init {
-            val file = normalized.toFile()
-            if (!path.exists())
-                throw NoSuchFileException(file)
-            if (path.isDirectory())
-                throw AccessDeniedException(file, reason = "Not a file but a directory")
-            if (!path.isReadable())
-                throw AccessDeniedException(file, reason = "Is not readable")
-        }
-
+        override val text: String
+        override val origin: String
+        override val name: String
         override val isFromResources = false
         override val isFromFilesystem = true
-        override val origin = relative(normalized).toString()
-        override fun getCharStream(): CharStream = CharStreams.fromPath(normalized)
-        override fun readText() = normalized.readText()
+
+        init {
+            val normalized = path.normalize()
+            origin = relative(normalized).toString()
+            try {
+                text = normalized.readText()
+                name = normalized.toFile().nameWithoutExtension
+            } catch (nfx: java.nio.file.NoSuchFileException) {
+                throw NoSuchFileException(normalized.toFile()).also { it.initCause(nfx) }
+            } catch (iox: IOException) {
+                throw FileSystemException(normalized.toFile()).also { it.initCause(iox) }
+            }
+        }
     }
 
     /**
@@ -114,6 +108,12 @@ sealed class SourceCode {
     class Resource(pathString: String): SourceCode() {
         private val normalized = "/" + Path.of(pathString).normalize().toMutableList().joinToString("/")
 
+        override val isFromResources = true
+        override val isFromFilesystem = false
+        override val origin = "$libraryFilePrefix$normalized"
+        override val text: String
+        override val name: String
+
         init {
             val rscURL = object {}.javaClass.getResource(normalized)
             if (rscURL == null) {
@@ -123,32 +123,19 @@ sealed class SourceCode {
                     reason = "looked in resources rooted at $rscRoot"
                 )
             }
-        }
-
-        override val isFromResources = true
-        override val isFromFilesystem = false
-        override val origin = "$libraryFilePrefix$normalized"
-        public override fun getCharStream(): CharStream {
-            val inpStr = object {}.javaClass.getResourceAsStream(normalized)!!
-            // CharStreams.fromStream() doesn't allow us to set the stream name properly, so we use a lower level api
-            val channel = Channels.newChannel(inpStr)
-            return CharStreams.fromChannel(channel, StandardCharsets.UTF_8, 4096, CodingErrorAction.REPLACE, origin, -1)
-        }
-
-        override fun readText(): String {
             val stream = object {}.javaClass.getResourceAsStream(normalized)
-            return stream!!.bufferedReader().use { r -> r.readText() }
+            text = stream!!.reader().use { it.readText() }
+            name = Path.of(pathString).toFile().nameWithoutExtension
         }
     }
 
     /**
      * SourceCode for internally generated nodes (usually Modules)
      */
-    class Generated(name: String) : SourceCode() {
-        override fun getCharStream(): CharStream = throw IOException("generated code nodes doesn't have a stream to read")
+    class Generated(override val name: String) : SourceCode() {
         override val isFromResources: Boolean = false
         override val isFromFilesystem: Boolean = false
         override val origin: String = name
-        override fun readText() = throw IOException("generated code nodes don't have a text representation")
+        override val text: String = "<generated code node, no text representation>"
     }
 }

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

@@ -0,0 +1,120 @@
+package prog8.code.core
+
+import com.github.michaelbull.result.Err
+import com.github.michaelbull.result.Ok
+import com.github.michaelbull.result.Result
+
+
+class ZeropageAllocationError(message: String) : Exception(message)
+
+
+abstract class Zeropage(protected val options: CompilationOptions) {
+
+    abstract val SCRATCH_B1 : UInt      // temp storage for a single byte
+    abstract val SCRATCH_REG : UInt     // temp storage for a register, must be B1+1
+    abstract val SCRATCH_W1 : UInt      // temp storage 1 for a word  $fb+$fc
+    abstract val SCRATCH_W2 : UInt      // temp storage 2 for a word  $fb+$fc
+
+    data class ZpAllocation(val address: UInt, val dt: DataType, val size: Int)
+
+    // the variables allocated into Zeropage.
+    // name (scoped) ==> pair of address to (Datatype + bytesize)
+    val allocatedVariables = mutableMapOf<List<String>, ZpAllocation>()
+
+    val free = mutableListOf<UInt>()     // subclasses must set this to the appropriate free locations.
+
+    fun removeReservedFromFreePool() {
+        synchronized(this) {
+            for (reserved in options.zpReserved)
+                reserve(reserved)
+
+            free.removeAll(setOf(SCRATCH_B1, SCRATCH_REG, SCRATCH_W1, SCRATCH_W1 + 1u, SCRATCH_W2, SCRATCH_W2 + 1u))
+        }
+    }
+
+    fun availableBytes() = if(options.zeropage== ZeropageType.DONTUSE) 0 else free.size
+    fun hasByteAvailable() = if(options.zeropage== ZeropageType.DONTUSE) false else free.isNotEmpty()
+    fun hasWordAvailable(): Boolean {
+        if(options.zeropage== ZeropageType.DONTUSE)
+            return false
+
+        return free.windowed(2).any { it[0] == it[1] - 1u }
+    }
+
+    fun allocate(name: List<String>,
+                 datatype: DataType,
+                 numElements: Int?,
+                 position: Position?,
+                 errors: IErrorReporter
+    ): Result<Pair<UInt, Int>, ZeropageAllocationError> {
+
+        require(name.isEmpty() || name !in allocatedVariables) {"name can't be allocated twice"}
+
+        if(options.zeropage== ZeropageType.DONTUSE)
+            return Err(ZeropageAllocationError("zero page usage has been disabled"))
+
+        val size: Int =
+                when (datatype) {
+                    in IntegerDatatypes -> options.compTarget.memorySize(datatype)
+                    DataType.STR, in ArrayDatatypes  -> {
+                        val memsize = options.compTarget.memorySize(datatype, numElements!!)
+                        if(position!=null)
+                            errors.warn("allocating a large value in zeropage; str/array $memsize bytes", position)
+                        else
+                            errors.warn("$name: allocating a large value in zeropage; str/array $memsize bytes", Position.DUMMY)
+                        memsize
+                    }
+                    DataType.FLOAT -> {
+                        if (options.floats) {
+                            val memsize = options.compTarget.memorySize(DataType.FLOAT)
+                            if(position!=null)
+                                errors.warn("allocating a large value in zeropage; float $memsize bytes", position)
+                            else
+                                errors.warn("$name: allocating a large value in zeropage; float $memsize bytes", Position.DUMMY)
+                            memsize
+                        } else return Err(ZeropageAllocationError("floating point option not enabled"))
+                    }
+                    else -> return Err(ZeropageAllocationError("cannot put datatype $datatype in zeropage"))
+                }
+
+        synchronized(this) {
+            if(free.size > 0) {
+                if(size==1) {
+                    for(candidate in free.minOrNull()!! .. free.maxOrNull()!!+1u) {
+                        if(oneSeparateByteFree(candidate))
+                            return Ok(Pair(makeAllocation(candidate, 1, datatype, name), 1))
+                    }
+                    return Ok(Pair(makeAllocation(free[0], 1, datatype, name), 1))
+                }
+                for(candidate in free.minOrNull()!! .. free.maxOrNull()!!+1u) {
+                    if (sequentialFree(candidate, size))
+                        return Ok(Pair(makeAllocation(candidate, size, datatype, name), size))
+                }
+            }
+        }
+
+        return Err(ZeropageAllocationError("no more free space in ZP to allocate $size sequential bytes"))
+    }
+
+    private fun reserve(range: UIntRange) = free.removeAll(range)
+
+    private fun makeAllocation(address: UInt, size: Int, datatype: DataType, name: List<String>): UInt {
+        require(size>=0)
+        free.removeAll(address until address+size.toUInt())
+        if(name.isNotEmpty()) {
+            allocatedVariables[name] = when(datatype) {
+                in NumericDatatypes -> ZpAllocation(address, datatype, size)        // numerical variables in zeropage never have an initial value here because they are set in separate initializer assignments
+                DataType.STR -> ZpAllocation(address, datatype, size)
+                in ArrayDatatypes -> ZpAllocation(address, datatype, size)
+                else -> throw AssemblyError("invalid dt")
+            }
+        }
+        return address
+    }
+
+    private fun oneSeparateByteFree(address: UInt) = address in free && address-1u !in free && address+1u !in free
+    private fun sequentialFree(address: UInt, size: Int): Boolean {
+        require(size>0)
+        return free.containsAll((address until address+size.toUInt()).toList())
+    }
+}

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

@@ -0,0 +1,28 @@
+package prog8.code.target
+
+import prog8.code.core.*
+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 {
+        const val NAME = "atari"
+    }
+
+    override fun memorySize(dt: DataType): Int {
+        return when(dt) {
+            in ByteDatatypes -> 1
+            in WordDatatypes, in PassByReferenceDatatypes -> 2
+            DataType.FLOAT -> machine.FLOAT_MEM_SIZE
+            else -> Int.MIN_VALUE
+        }
+    }
+
+    override fun memorySize(arrayDt: DataType, numElements: Int) =
+        memorySize(ArrayToElementTypes.getValue(arrayDt)) * numElements
+}

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

@@ -0,0 +1,20 @@
+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.c128.C128MachineDefinition
+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 {
+        const val NAME = "c128"
+    }
+}

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

@@ -0,0 +1,20 @@
+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.c64.C64MachineDefinition
+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"
+    }
+}

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

@@ -0,0 +1,20 @@
+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.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 {
+        const val NAME = "cx16"
+    }
+}

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

@@ -0,0 +1,39 @@
+package prog8.code.target
+
+import com.github.michaelbull.result.fold
+import prog8.code.core.Encoding
+import prog8.code.core.IStringEncoding
+import prog8.code.core.InternalCompilerException
+import prog8.code.target.cbm.AtasciiEncoding
+import prog8.code.target.cbm.IsoEncoding
+import prog8.code.target.cbm.PetsciiEncoding
+
+
+object Encoder: IStringEncoding {
+    override fun encodeString(str: String, encoding: Encoding): List<UByte> {
+        val coded = when(encoding) {
+            Encoding.PETSCII -> PetsciiEncoding.encodePetscii(str, true)
+            Encoding.SCREENCODES -> PetsciiEncoding.encodeScreencode(str, true)
+            Encoding.ISO -> IsoEncoding.encode(str)
+            Encoding.ATASCII -> AtasciiEncoding.encode(str)
+            else -> throw InternalCompilerException("unsupported encoding $encoding")
+        }
+        return coded.fold(
+            failure = { throw it },
+            success = { it }
+        )
+    }
+    override fun decodeString(bytes: List<UByte>, encoding: Encoding): String {
+        val decoded = when(encoding) {
+            Encoding.PETSCII -> PetsciiEncoding.decodePetscii(bytes, true)
+            Encoding.SCREENCODES -> PetsciiEncoding.decodeScreencode(bytes, true)
+            Encoding.ISO -> IsoEncoding.decode(bytes)
+            Encoding.ATASCII -> AtasciiEncoding.decode(bytes)
+            else -> throw InternalCompilerException("unsupported encoding $encoding")
+        }
+        return decoded.fold(
+            failure = { throw it },
+            success = { it }
+        )
+    }
+}

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

@@ -0,0 +1,27 @@
+package prog8.code.target
+
+import prog8.code.core.*
+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 {
+        const val NAME = "virtual"
+    }
+
+    override fun memorySize(dt: DataType): Int {
+        return when(dt) {
+            in ByteDatatypes -> 1
+            in WordDatatypes, in PassByReferenceDatatypes -> 2
+            DataType.FLOAT -> machine.FLOAT_MEM_SIZE
+            else -> Int.MIN_VALUE
+        }
+    }
+
+    override fun memorySize(arrayDt: DataType, numElements: Int) =
+        memorySize(ArrayToElementTypes.getValue(arrayDt)) * numElements
+}

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

@@ -0,0 +1,65 @@
+package prog8.code.target.atari
+
+import prog8.code.core.*
+import prog8.code.target.c64.normal6502instructions
+import java.nio.file.Path
+
+
+class AtariMachineDefinition: IMachineDefinition {
+
+    override val cpu = CpuType.CPU6502
+
+    override val FLOAT_MAX_POSITIVE = 9.999999999e97
+    override val FLOAT_MAX_NEGATIVE = -9.999999999e97
+    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 ESTACK_LO = 0x1a00u     //  $1a00-$1aff inclusive      // TODO
+    override val ESTACK_HI = 0x1b00u     //  $1b00-$1bff inclusive      // TODO
+
+    override lateinit var zeropage: Zeropage
+
+    override fun getFloat(num: Number) = TODO("float from number")
+
+    override fun importLibs(compilerOptions: CompilationOptions, compilationTargetName: String): List<String> {
+        return if (compilerOptions.output == OutputType.XEX)
+            listOf("syslib")
+        else
+            emptyList()
+    }
+
+    override fun launchEmulator(selectedEmulator: Int, programNameWithPath: Path) {
+        val emulatorName: String
+        val cmdline: List<String>
+        when(selectedEmulator) {
+            1 -> {
+                emulatorName = "atari800"
+                cmdline = listOf(emulatorName, "-xl", "-xl-rev", "2", "-nobasic", "-run", "${programNameWithPath}.xex")
+            }
+            2 -> {
+                emulatorName = "altirra"
+                cmdline = listOf("Altirra64.exe", "${programNameWithPath.normalize()}.xex")
+            }
+            else -> {
+                System.err.println("Atari target only supports atari800 and altirra emulators.")
+                return
+            }
+        }
+
+        // TODO monlist?
+
+        println("\nStarting Atari800XL emulator $emulatorName...")
+        val processb = ProcessBuilder(cmdline).inheritIO()
+        val process: Process = processb.start()
+        process.waitFor()
+    }
+
+    override fun isIOAddress(address: UInt): Boolean = address==0u || address==1u || address in 0xd000u..0xdfffu        // TODO
+
+    override fun initializeZeropage(compilerOptions: CompilationOptions) {
+        zeropage = AtariZeropage(compilerOptions)
+    }
+
+    override val opcodeNames = normal6502instructions
+}

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

@@ -0,0 +1,45 @@
+package prog8.code.target.atari
+
+import prog8.code.core.CompilationOptions
+import prog8.code.core.InternalCompilerException
+import prog8.code.core.Zeropage
+import prog8.code.core.ZeropageType
+
+class AtariZeropage(options: CompilationOptions) : Zeropage(options) {
+
+    override val SCRATCH_B1 = 0xcbu      // temp storage for a single byte
+    override val SCRATCH_REG = 0xccu     // temp storage for a register, must be B1+1
+    override val SCRATCH_W1 = 0xcdu      // temp storage 1 for a word  $cd+$ce
+    override val SCRATCH_W2 = 0xcfu      // temp storage 2 for a word  $cf+$d0        TODO is $d0 okay to use?
+
+
+    init {
+        if (options.floats && options.zeropage !in arrayOf(
+                ZeropageType.FLOATSAFE,
+                ZeropageType.BASICSAFE,
+                ZeropageType.DONTUSE
+            ))
+            throw InternalCompilerException("when floats are enabled, zero page type should be 'floatsafe' or 'basicsafe' or 'dontuse'")
+
+        when (options.zeropage) {
+            ZeropageType.FULL -> {
+                // TODO all atari usable zero page locations, except the ones used by the system's IRQ routine
+                free.addAll(0x00u..0xffu)
+                // TODO atari  free.removeAll(setOf(0xa0u, 0xa1u, 0xa2u, 0x91u, 0xc0u, 0xc5u, 0xcbu, 0xf5u, 0xf6u))        // these are updated by IRQ
+            }
+            ZeropageType.KERNALSAFE -> {
+                free.addAll(0x80u..0xffu)       // TODO
+            }
+            ZeropageType.BASICSAFE,
+            ZeropageType.FLOATSAFE -> {
+                free.addAll(0x80u..0xffu)       // TODO
+                free.removeAll(0xd4u .. 0xefu)      // floating point storage
+            }
+            ZeropageType.DONTUSE -> {
+                free.clear()  // don't use zeropage at all
+            }
+        }
+
+        removeReservedFromFreePool()
+    }
+}

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

@@ -0,0 +1,55 @@
+package prog8.code.target.c128
+
+import prog8.code.core.*
+import prog8.code.target.c64.normal6502instructions
+import prog8.code.target.cbm.Mflpt5
+import java.nio.file.Path
+
+
+class C128MachineDefinition: 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 = 0x1c01u
+
+    // the 2*256 byte evaluation stack (on which bytes, words, and even floats are stored during calculations)
+    override val ESTACK_LO = 0x1a00u     //  $1a00-$1aff inclusive
+    override val ESTACK_HI = 0x1b00u     //  $1b00-$1bff inclusive
+
+    override lateinit var zeropage: Zeropage
+
+    override fun getFloat(num: Number) = Mflpt5.fromNumber(num)
+
+    override fun importLibs(compilerOptions: CompilationOptions, compilationTargetName: String): List<String> {
+        return if (compilerOptions.launcher == CbmPrgLauncherType.BASIC || compilerOptions.output == OutputType.PRG)
+            listOf("syslib")
+        else
+            emptyList()
+    }
+
+    override fun launchEmulator(selectedEmulator: Int, programNameWithPath: Path) {
+        if(selectedEmulator!=1) {
+            System.err.println("The c128 target only supports the main emulator (Vice).")
+            return
+        }
+
+        println("\nStarting C-128 emulator x128...")
+        val viceMonlist = viceMonListName(programNameWithPath.toString())
+        val cmdline = listOf("x128", "-silent", "-moncommands", viceMonlist,
+                "-autostartprgmode", "1", "-autostart-warp", "-autostart", "${programNameWithPath}.prg")
+        val processb = ProcessBuilder(cmdline).inheritIO()
+        val process: Process = processb.start()
+        process.waitFor()
+    }
+
+    override fun isIOAddress(address: UInt): Boolean = address==0u || address==1u || address in 0xd000u..0xdfffu
+
+    override fun initializeZeropage(compilerOptions: CompilationOptions) {
+        zeropage = C128Zeropage(compilerOptions)
+    }
+
+    override val opcodeNames = normal6502instructions
+}

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

@@ -0,0 +1,43 @@
+package prog8.code.target.c128
+
+import prog8.code.core.CompilationOptions
+import prog8.code.core.InternalCompilerException
+import prog8.code.core.Zeropage
+import prog8.code.core.ZeropageType
+
+
+class C128Zeropage(options: CompilationOptions) : Zeropage(options) {
+
+    override val SCRATCH_B1 = 0x9bu      // temp storage for a single byte
+    override val SCRATCH_REG = 0x9cu     // 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 && 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 -> {
+                // TODO all c128 usable zero page locations, except the ones used by the system's IRQ routine
+                free.addAll(0x0au..0xffu)       // TODO c128 what about $02-$09?
+                // TODO c128  free.removeAll(setOf(0xa0u, 0xa1u, 0xa2u, 0x91u, 0xc0u, 0xc5u, 0xcbu, 0xf5u, 0xf6u))        // these are updated by IRQ
+            }
+            ZeropageType.KERNALSAFE,
+            ZeropageType.FLOATSAFE,
+            ZeropageType.BASICSAFE -> {
+                free.clear()   // TODO c128 usable zero page addresses
+            }
+            ZeropageType.DONTUSE -> {
+                free.clear()  // don't use zeropage at all
+            }
+        }
+
+        removeReservedFromFreePool()
+    }
+}

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

@@ -0,0 +1,76 @@
+package prog8.code.target.c64
+
+import prog8.code.core.*
+import prog8.code.target.cbm.Mflpt5
+import java.io.IOException
+import java.nio.file.Path
+
+
+class C64MachineDefinition: 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 = 0x0801u
+
+    // the 2*256 byte evaluation stack (on which bytes, words, and even floats are stored during calculations)
+    override val ESTACK_LO = 0xce00u     //  $ce00-$ceff inclusive
+    override val ESTACK_HI = 0xcf00u     //  $ce00-$ceff inclusive
+
+    override lateinit var zeropage: Zeropage
+
+    override fun getFloat(num: Number) = Mflpt5.fromNumber(num)
+
+    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 c64 target only supports the main emulator (Vice).")
+            return
+        }
+
+        for(emulator in listOf("x64sc", "x64")) {
+            println("\nStarting C-64 emulator $emulator...")
+            val viceMonlist = viceMonListName(programNameWithPath.toString())
+            val cmdline = listOf(emulator, "-silent", "-moncommands", viceMonlist,
+                    "-autostartprgmode", "1", "-autostart-warp", "-autostart", "${programNameWithPath}.prg")
+            val processb = ProcessBuilder(cmdline).inheritIO()
+            val process: Process
+            try {
+                process=processb.start()
+            } catch(x: IOException) {
+                continue  // try the next emulator executable
+            }
+            process.waitFor()
+            break
+        }
+    }
+
+    override fun isIOAddress(address: UInt): Boolean = address==0u || address==1u || address in 0xd000u..0xdfffu
+
+    override fun initializeZeropage(compilerOptions: CompilationOptions) {
+        zeropage = C64Zeropage(compilerOptions)
+    }
+
+    override val opcodeNames = normal6502instructions
+}
+
+
+// 6502 opcodes (including aliases and illegal opcodes), these cannot be used as variable or label names
+internal val normal6502instructions = setOf(
+    "adc", "ahx", "alr", "anc", "and", "ane", "arr", "asl", "asr", "axs", "bcc", "bcs",
+    "beq", "bge", "bit", "blt", "bmi", "bne", "bpl", "brk", "bvc", "bvs", "clc",
+    "cld", "cli", "clv", "cmp", "cpx", "cpy", "dcm", "dcp", "dec", "dex", "dey",
+    "eor", "gcc", "gcs", "geq", "gge", "glt", "gmi", "gne", "gpl", "gvc", "gvs",
+    "inc", "ins", "inx", "iny", "isb", "isc", "jam", "jmp", "jsr", "lae", "las",
+    "lax", "lda", "lds", "ldx", "ldy", "lsr", "lxa", "nop", "ora", "pha", "php",
+    "pla", "plp", "rla", "rol", "ror", "rra", "rti", "rts", "sax", "sbc", "sbx",
+    "sec", "sed", "sei", "sha", "shl", "shr", "shs", "shx", "shy", "slo", "sre",
+    "sta", "stx", "sty", "tas", "tax", "tay", "tsx", "txa", "txs", "tya", "xaa")

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

@@ -0,0 +1,74 @@
+package prog8.code.target.c64
+
+import prog8.code.core.CompilationOptions
+import prog8.code.core.InternalCompilerException
+import prog8.code.core.Zeropage
+import prog8.code.core.ZeropageType
+
+
+class C64Zeropage(options: CompilationOptions) : Zeropage(options) {
+
+    override val SCRATCH_B1 = 0x02u      // temp storage for a single byte
+    override val SCRATCH_REG = 0x03u     // temp storage for a register, must be B1+1
+    override val SCRATCH_W1 = 0xfbu      // temp storage 1 for a word  $fb+$fc
+    override val SCRATCH_W2 = 0xfdu      // temp storage 2 for a word  $fd+$fe
+
+
+    init {
+        if (options.floats && options.zeropage !in arrayOf(
+                ZeropageType.FLOATSAFE,
+                ZeropageType.BASICSAFE,
+                ZeropageType.DONTUSE
+            ))
+            throw InternalCompilerException("when floats are enabled, zero page type should be 'floatsafe' or 'basicsafe' or 'dontuse'")
+
+        if (options.zeropage == ZeropageType.FULL) {
+            free.addAll(0x02u..0xffu)
+            free.removeAll(setOf(SCRATCH_B1, SCRATCH_REG, SCRATCH_W1, SCRATCH_W1+1u, SCRATCH_W2, SCRATCH_W2+1u))
+            free.removeAll(setOf(0xa0u, 0xa1u, 0xa2u, 0x91u, 0xc0u, 0xc5u, 0xcbu, 0xf5u, 0xf6u))        // these are updated by IRQ
+        } else {
+            if (options.zeropage == ZeropageType.KERNALSAFE || options.zeropage == ZeropageType.FLOATSAFE) {
+                free.addAll(listOf(
+                        0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, 0x10, 0x11,
+                        0x16, 0x17, 0x18, 0x19, 0x1a,
+                        0x1b, 0x1c, 0x1d, 0x1e, 0x1f, 0x20, 0x21,
+                        0x22, 0x23, 0x24, 0x25,
+                        0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f, 0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46,
+                        0x47, 0x48, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f, 0x51, 0x52, 0x53,
+                        0x57, 0x58, 0x59, 0x5a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f, 0x60,
+                        0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68,
+                        0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f, 0x70, 0x71, 0x72,
+                        0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 0x7a, 0x7b, 0x7c,
+                        0x7d, 0x7e, 0x7f, 0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89, 0x8a,
+                        0x8b, 0x8c, 0x8d, 0x8e, 0x8f, 0xff
+                        // 0x90-0xfa is 'kernal work storage area'
+                ).map{it.toUInt()})
+            }
+
+            if (options.zeropage == ZeropageType.FLOATSAFE) {
+                // remove the zeropage locations used for floating point operations from the free list
+                free.removeAll(listOf(
+                        0x22, 0x23, 0x24, 0x25,
+                        0x10, 0x11, 0x12, 0x26, 0x27, 0x28, 0x29, 0x2a,
+                        0x57, 0x58, 0x59, 0x5a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f, 0x60,
+                        0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68,
+                        0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f, 0x70, 0x71, 0x72,
+                        0x8b, 0x8c, 0x8d, 0x8e, 0x8f, 0xff
+                ).map{it.toUInt()})
+            }
+
+            if(options.zeropage!= ZeropageType.DONTUSE) {
+                // add the free Zp addresses
+                // these are valid for the C-64 but allow BASIC to keep running fully *as long as you don't use tape I/O*
+                free.addAll(listOf(0x04, 0x05, 0x06, 0x0a, 0x0e,
+                        0x92, 0x96, 0x9b, 0x9c, 0x9e, 0x9f, 0xa5, 0xa6,
+                        0xb0, 0xb1, 0xbe, 0xbf, 0xf9).map{it.toUInt()})
+            } else {
+                // don't use the zeropage at all
+                free.clear()
+            }
+        }
+
+        removeReservedFromFreePool()
+    }
+}

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

@@ -0,0 +1,214 @@
+package prog8.code.target.cbm
+
+import com.github.michaelbull.result.Ok
+import com.github.michaelbull.result.Result
+import java.io.CharConversionException
+
+object AtasciiEncoding {
+
+    private val decodeTable: CharArray = charArrayOf(
+        // $00
+        '♥',
+        '├',
+        '\uf130',    //  🮇    0x02 -> RIGHT ONE QUARTER BLOCK (CUS)
+        '┘',
+        '┤',
+        '┐',
+        '╱',
+        '╲',
+        '◢',
+        '▗',
+        '◣',
+        '▝',
+        '▘',
+        '\uf132',    //  🮂    0x1d -> UPPER ONE QUARTER BLOCK (CUS)
+        '▂',
+        '▖',
+
+        // $10
+     	'♣',
+        '┌',
+        '─',
+        '┼',
+        '•',
+        '▄',
+        '▎',
+        '┬',
+        '┴',
+        '▌',
+        '└',
+        '\u001b',           // $1b = escape
+        '\ufffe',           // UNDEFINED CHAR.   $1c = cursor up
+        '\ufffe',           // UNDEFINED CHAR.   $1d = cursor down
+        '\ufffe',           // UNDEFINED CHAR.   $1e = cursor left
+        '\ufffe',           // UNDEFINED CHAR.   $1f = cursor right
+
+        // $20
+        ' ',
+        '!',
+        '"',
+        '#',
+        '$',
+        '%',
+        '&',
+        '\'',
+        '(',
+        ')',
+        '*',
+        '+',
+        ',',
+        '-',
+        '.',
+        '/',
+
+        // $30
+     	'0',
+        '1',
+        '2',
+        '3',
+        '4',
+        '5',
+        '6',
+        '7',
+        '8',
+        '9',
+        ':',
+        ';',
+        '<',
+        '=',
+        '>',
+        '?',
+
+        // $40
+     	'@',
+        'A',
+        'B',
+        'C',
+        'D',
+        'E',
+        'F',
+        'G',
+        'H',
+        'I',
+        'J',
+        'K',
+        'L',
+        'M',
+        'N',
+        'O',
+
+        // $50
+        'P',
+        'Q',
+        'R',
+        'S',
+        'T',
+        'U',
+        'V',
+        'W',
+        'X',
+        'Y',
+        'Z',
+        '[',
+        '\\',
+        ']',
+        '^',
+        '_',
+
+        // $60
+        '♦',
+        'a',
+        'b',
+        'c',
+        'd',
+        'e',
+        'f',
+        'g',
+        'h',
+        'i',
+        'j',
+        'k',
+        'l',
+        'm',
+        'n',
+        'o',
+
+        // $70
+        'p',
+        'q',
+        'r',
+        's',
+        't',
+        'u',
+        'v',
+        'w',
+        'x',
+        'y',
+        'z',
+        '♠',
+        '|',
+        '\u000c',    //       $7d -> FORM FEED (CLEAR SCREEN)
+        '\u0008',    //       $7e -> BACKSPACE
+        '\u0009',    //       $7f -> TAB
+
+        // $80-$ff are reversed video characters + various special characters.
+        '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe',
+        '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe',
+        // $90
+        '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe',
+        '\ufffe',
+        '\ufffe',
+        '\ufffe',
+        '\n',               // $9b -> EOL/RETURN
+        '\ufffe',           // UNDEFINED   $9c = DELETE LINE
+        '\ufffe',           // UNDEFINED   $9d = INSERT LINE
+        '\ufffe',           // UNDEFINED   $9e = CLEAR TAB STOP
+        '\ufffe',           // UNDEFINED   $9f = SET TAB STOP
+        // $a0
+        '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe',
+        '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe',
+        // $b0
+        '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe',
+        '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe',
+        // $c0
+        '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe',
+        '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe',
+        // $d0
+        '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe',
+        '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe',
+        // $e0
+        '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe',
+        '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe',
+        // $f0
+        '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe', '\ufffe',
+        '\ufffe',
+        '\ufffe',
+        '\ufffe',
+        '\ufffe',
+        '\ufffe',
+        '\u0007',           // $fd = bell/beep
+        '\u007f',           // $fe = DELETE
+        '\ufffe'            // UNDEFINED     $ff = INSERT
+    )
+
+    private val encodeTable = decodeTable.withIndex().associate{it.value to it.index}
+
+
+    fun encode(str: String): Result<List<UByte>, CharConversionException> {
+        val mapped = str.map { chr ->
+            when (chr) {
+                '\u0000' -> 0u
+                in '\u8000'..'\u80ff' -> {
+                    // special case: take the lower 8 bit hex value directly
+                    (chr.code - 0x8000).toUByte()
+                }
+                else -> encodeTable.getValue(chr).toUByte()
+            }
+        }
+        return Ok(mapped)
+    }
+
+    fun decode(bytes: List<UByte>): Result<String, CharConversionException> {
+        return Ok(bytes.map { decodeTable[it.toInt()] }.joinToString(""))
+    }
+}

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

@@ -0,0 +1,18 @@
+package prog8.code.target.cbm
+
+import prog8.code.core.*
+
+
+internal object CbmMemorySizer: IMemSizer {
+    override fun memorySize(dt: DataType): Int {
+        return when(dt) {
+            in ByteDatatypes -> 1
+            in WordDatatypes, in PassByReferenceDatatypes -> 2
+            DataType.FLOAT -> Mflpt5.FLOAT_MEM_SIZE
+            else -> Int.MIN_VALUE
+        }
+    }
+
+    override fun memorySize(arrayDt: DataType, numElements: Int) =
+        memorySize(ArrayToElementTypes.getValue(arrayDt)) * numElements
+}

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

@@ -0,0 +1,37 @@
+package prog8.code.target.cbm
+
+import com.github.michaelbull.result.Err
+import com.github.michaelbull.result.Ok
+import com.github.michaelbull.result.Result
+import java.io.CharConversionException
+import java.nio.charset.Charset
+
+object IsoEncoding {
+    val charset: Charset = Charset.forName("ISO-8859-15")
+
+    fun encode(str: String): Result<List<UByte>, CharConversionException> {
+        return try {
+            val mapped = str.map { chr ->
+                when (chr) {
+                    '\u0000' -> 0u
+                    in '\u8000'..'\u80ff' -> {
+                        // special case: take the lower 8 bit hex value directly
+                        (chr.code - 0x8000).toUByte()
+                    }
+                    else -> charset.encode(chr.toString())[0].toUByte()
+                }
+            }
+            Ok(mapped)
+        } catch (ce: CharConversionException) {
+            Err(ce)
+        }
+    }
+
+    fun decode(bytes: List<UByte>): Result<String, CharConversionException> {
+        return try {
+            Ok(String(bytes.map { it.toByte() }.toByteArray(), charset))
+        } catch (ce: CharConversionException) {
+            Err(ce)
+        }
+    }
+}

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

@@ -0,0 +1,78 @@
+package prog8.code.target.cbm
+
+import prog8.code.core.IMachineFloat
+import prog8.code.core.InternalCompilerException
+import kotlin.math.absoluteValue
+import kotlin.math.pow
+
+
+data class Mflpt5(val b0: UByte, val b1: UByte, val b2: UByte, val b3: UByte, val b4: UByte): IMachineFloat {
+
+    companion object {
+        const val FLOAT_MAX_POSITIVE = 1.7014118345e+38         // bytes: 255,127,255,255,255
+        const val FLOAT_MAX_NEGATIVE = -1.7014118345e+38        // bytes: 255,255,255,255,255
+        const val FLOAT_MEM_SIZE = 5
+
+        val zero = Mflpt5(0u, 0u, 0u, 0u, 0u)
+        fun fromNumber(num: Number): Mflpt5 {
+            // see https://en.wikipedia.org/wiki/Microsoft_Binary_Format
+            // and https://sourceforge.net/p/acme-crossass/code-0/62/tree/trunk/ACME_Lib/cbm/mflpt.a
+            // and https://en.wikipedia.org/wiki/IEEE_754-1985
+
+            val flt = num.toDouble()
+            if (flt < FLOAT_MAX_NEGATIVE || flt > FLOAT_MAX_POSITIVE)
+                throw InternalCompilerException("floating point number out of 5-byte mflpt range: $this")
+            if (flt == 0.0)
+                return zero
+
+            val sign = if (flt < 0.0) 0x80L else 0x00L
+            var exponent = 128 + 32    // 128 is cbm's bias, 32 is this algo's bias
+            var mantissa = flt.absoluteValue
+
+            // if mantissa is too large, shift right and adjust exponent
+            while (mantissa >= 0x100000000) {
+                mantissa /= 2.0
+                exponent++
+            }
+            // if mantissa is too small, shift left and adjust exponent
+            while (mantissa < 0x80000000) {
+                mantissa *= 2.0
+                exponent--
+            }
+
+            return when {
+                exponent < 0 -> zero  // underflow, use zero instead
+                exponent > 255 -> throw InternalCompilerException("floating point overflow: $this")
+                exponent == 0 -> zero
+                else -> {
+                    val mantLong = mantissa.toLong()
+                    Mflpt5(
+                        exponent.toUByte(),
+                        (mantLong.and(0x7f000000L) ushr 24).or(sign).toUByte(),
+                        (mantLong.and(0x00ff0000L) ushr 16).toUByte(),
+                        (mantLong.and(0x0000ff00L) ushr 8).toUByte(),
+                        (mantLong.and(0x000000ffL)).toUByte()
+                    )
+                }
+            }
+        }
+    }
+
+    override fun toDouble(): Double {
+        if (this == zero) return 0.0
+        val exp = b0.toInt() - 128
+        val sign = (b1.toInt() and 0x80) > 0
+        val number = 0x80000000L.or(b1.toLong() shl 24).or(b2.toLong() shl 16).or(b3.toLong() shl 8).or(b4.toLong())
+        val result = number.toDouble() * (2.0).pow(exp) / 0x100000000
+        return if (sign) -result else result
+    }
+
+    override fun makeFloatFillAsm(): String {
+        val b0 = "$" + b0.toString(16).padStart(2, '0')
+        val b1 = "$" + b1.toString(16).padStart(2, '0')
+        val b2 = "$" + b2.toString(16).padStart(2, '0')
+        val b3 = "$" + b3.toString(16).padStart(2, '0')
+        val b4 = "$" + b4.toString(16).padStart(2, '0')
+        return "$b0, $b1, $b2, $b3, $b4"
+    }
+}

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

@@ -1,15 +1,14 @@
-package prog8.compiler.target.cbm
+package prog8.code.target.cbm
 
 import com.github.michaelbull.result.Err
 import com.github.michaelbull.result.Ok
 import com.github.michaelbull.result.Result
-import prog8.ast.antlr.escape
 import java.io.CharConversionException
 
-object Petscii {
+object PetsciiEncoding {
 
     // decoding:  from Petscii/Screencodes (0-255) to unicode
-    // character tables used from https://github.com/dj51d/cbmcodecs
+    // character tables used from https://github.com/irmen/cbmcodecs2
 
     private val decodingPetsciiLowercase = charArrayOf(
         '\u0000',    //       0x00 -> \u0000
@@ -159,7 +158,7 @@ object Petscii {
         '\uf105',    //       0x90 -> BLACK COLOR SWITCH (CUS)
         '\uf11e',    //      0x91 -> CURSOR UP (CUS)
         '\uf11b',    //      0x92 -> REVERSE VIDEO OFF (CUS)
-        '\u000c',    //       0x93 -> FORM FEED
+        '\u000c',    //       0x93 -> FORM FEED (CLEAR SCREEN)
         '\uf121',    //      0x94 -> INSERT (CUS)
         '\uf106',    //       0x95 -> BROWN COLOR SWITCH (CUS)
         '\uf107',    //       0x96 -> LIGHT RED COLOR SWITCH (CUS)
@@ -195,7 +194,7 @@ object Petscii {
         '\u258e',    //  ▎    0xB4 -> LEFT ONE QUARTER BLOCK
         '\u258d',    //  ▍    0xB5 -> LEFT THREE EIGTHS BLOCK
         '\uf131',    //      0xB6 -> RIGHT THREE EIGHTHS BLOCK (CUS)
-        '\uf132',    //      0xB7 -> UPPER ONE QUARTER BLOCK (CUS)
+        '\uf132',    //  🮂    0xB7 -> UPPER ONE QUARTER BLOCK (CUS)
         '\uf133',    //      0xB8 -> UPPER THREE EIGHTS BLOCK (CUS)
         '\u2583',    //  ▃    0xB9 -> LOWER THREE EIGHTHS BLOCK
         '\u2713',    //  ✓    0xBA -> CHECK MARK
@@ -246,7 +245,7 @@ object Petscii {
         '\u2595',    //  ▕    0xE7 -> RIGHT ONE EIGHTH BLOCK
         '\uf12f',    //      0xE8 -> LOWER HALF BLOCK MEDIUM SHADE (CUS)
         '\uf13a',    //      0xE9 -> MEDIUM SHADE SLASHED RIGHT (CUS)
-        '\uf130',    //      0xEA -> RIGHT ONE QUARTER BLOCK (CUS)
+        '\uf130',    //  🮇    0xEA -> RIGHT ONE QUARTER BLOCK (CUS)
         '\u251c',    //  ├    0xEB -> BOX DRAWINGS LIGHT VERTICAL AND RIGHT
         '\u2597',    //  ▗    0xEC -> QUADRANT LOWER RIGHT
         '\u2514',    //  └    0xED -> BOX DRAWINGS LIGHT UP AND RIGHT
@@ -418,7 +417,7 @@ object Petscii {
         '\uf105',    //       0x90 -> BLACK COLOR SWITCH (CUS)
         '\uf11e',    //       0x91 -> CURSOR UP (CUS)
         '\uf11b',    //       0x92 -> REVERSE VIDEO OFF (CUS)
-        '\u000c',    //       0x93 -> FORM FEED
+        '\u000c',    //       0x93 -> FORM FEED (CLEAR SCREEN)
         '\uf121',    //       0x94 -> INSERT (CUS)
         '\uf106',    //       0x95 -> BROWN COLOR SWITCH (CUS)
         '\uf107',    //       0x96 -> LIGHT RED COLOR SWITCH (CUS)
@@ -1077,7 +1076,7 @@ object Petscii {
                 }
                 else -> {
                     val case = if (lowercase) "lower" else "upper"
-                    throw CharConversionException("no ${case}Petscii character for '${escape(chr.toString())}' (${chr.code})")
+                    throw CharConversionException("no ${case}Petscii character for '${chr}' (${chr.code})")
                 }
             }
         }
@@ -1095,13 +1094,17 @@ object Petscii {
         }
     }
 
-    fun decodePetscii(petscii: Iterable<UByte>, lowercase: Boolean = false): String {
-        return petscii.map {
-            val code = it.toInt()
-            if(code<0 || code>= decodingPetsciiLowercase.size)
-                throw CharConversionException("petscii $code out of range 0..${decodingPetsciiLowercase.size-1}")
-            if(lowercase) decodingPetsciiLowercase[code] else decodingPetsciiUppercase[code]
-        }.joinToString("")
+    fun decodePetscii(petscii: Iterable<UByte>, lowercase: Boolean = false): Result<String, CharConversionException> {
+        return try {
+            Ok(petscii.map {
+                val code = it.toInt()
+                if(code<0 || code>= decodingPetsciiLowercase.size)
+                    throw CharConversionException("petscii $code out of range 0..${decodingPetsciiLowercase.size-1}")
+                if(lowercase) decodingPetsciiLowercase[code] else decodingPetsciiUppercase[code]
+            }.joinToString(""))
+        } catch(ce: CharConversionException) {
+            return Err(ce)
+        }
     }
 
     fun encodeScreencode(text: String, lowercase: Boolean = false): Result<List<UByte>, CharConversionException> {
@@ -1116,7 +1119,7 @@ object Petscii {
                 }
                 else -> {
                     val case = if (lowercase) "lower" else "upper"
-                    throw CharConversionException("no ${case}Screencode character for '${escape(chr.toString())}' (${chr.code})")
+                    throw CharConversionException("no ${case}Screencode character for '${chr}' (${chr.code})")
                 }
             }
         }
@@ -1134,13 +1137,17 @@ object Petscii {
         }
     }
 
-    fun decodeScreencode(screencode: Iterable<UByte>, lowercase: Boolean = false): String {
-        return screencode.map {
-            val code = it.toInt()
-            if(code<0 || code>= decodingScreencodeLowercase.size)
-                throw CharConversionException("screencode $code out of range 0..${decodingScreencodeLowercase.size-1}")
-            if (lowercase) decodingScreencodeLowercase[code] else decodingScreencodeUppercase[code]
-        }.joinToString("")
+    fun decodeScreencode(screencode: Iterable<UByte>, lowercase: Boolean = false): Result<String, CharConversionException> {
+        return try {
+            Ok(screencode.map {
+                val code = it.toInt()
+                if(code<0 || code>= decodingScreencodeLowercase.size)
+                    throw CharConversionException("screencode $code out of range 0..${decodingScreencodeLowercase.size-1}")
+                if (lowercase) decodingScreencodeLowercase[code] else decodingScreencodeUppercase[code]
+            }.joinToString(""))
+        } catch(ce: CharConversionException) {
+            Err(ce)
+        }
     }
 
     fun petscii2scr(petscii_code: UByte, inverseVideo: Boolean): Result<UByte, CharConversionException> {

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

@@ -0,0 +1,77 @@
+package prog8.code.target.cx16
+
+import prog8.code.core.*
+import prog8.code.target.cbm.Mflpt5
+import java.nio.file.Path
+
+
+class CX16MachineDefinition: IMachineDefinition {
+
+    override val cpu = CpuType.CPU65c02
+
+    override val FLOAT_MAX_POSITIVE = Mflpt5.FLOAT_MAX_POSITIVE
+    override val FLOAT_MAX_NEGATIVE = Mflpt5.FLOAT_MAX_NEGATIVE
+    override val FLOAT_MEM_SIZE = Mflpt5.FLOAT_MEM_SIZE
+    override val PROGRAM_LOAD_ADDRESS = 0x0801u
+
+    // the 2*256 byte evaluation stack (on which bytes, words, and even floats are stored during calculations)
+    override val ESTACK_LO = 0x0400u        //  $0400-$04ff inclusive
+    override val ESTACK_HI = 0x0500u        //  $0500-$05ff inclusive
+
+    override lateinit var zeropage: Zeropage
+
+    override fun getFloat(num: Number) = Mflpt5.fromNumber(num)
+    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) {
+        val emulator: String
+        val extraArgs: List<String>
+
+        when(selectedEmulator) {
+            1 -> {
+                emulator = "x16emu"
+                extraArgs = emptyList()
+            }
+            2 -> {
+                emulator = "box16"
+                extraArgs = listOf("-sym", viceMonListName(programNameWithPath.toString()))
+            }
+            else -> {
+                System.err.println("Cx16 target only supports x16emu and box16 emulators.")
+                return
+            }
+        }
+
+        println("\nStarting Commander X16 emulator $emulator...")
+        val cmdline = listOf(emulator, "-scale", "2", "-run", "-prg", "${programNameWithPath}.prg") + extraArgs
+        val processb = ProcessBuilder(cmdline).inheritIO()
+        val process: Process = processb.start()
+        process.waitFor()
+    }
+
+    override fun isIOAddress(address: UInt): Boolean = address==0u || address==1u || address in 0x9f00u..0x9fffu
+
+    override fun initializeZeropage(compilerOptions: CompilationOptions) {
+        zeropage = CX16Zeropage(compilerOptions)
+    }
+
+    // 65c02 opcodes, these cannot be used as variable or label names
+    override val opcodeNames = setOf("adc", "and", "asl", "bcc", "bcs",
+            "beq", "bge", "bit", "blt", "bmi", "bne", "bpl", "brk", "bvc", "bvs", "clc",
+            "cld", "cli", "clv", "cmp", "cpx", "cpy", "dec", "dex", "dey",
+            "eor", "gcc", "gcs", "geq", "gge", "glt", "gmi", "gne", "gpl", "gvc", "gvs",
+            "inc", "inx", "iny", "jmp", "jsr",
+            "lda", "ldx", "ldy", "lsr", "nop", "ora", "pha", "php",
+            "pla", "plp", "rol", "ror", "rti", "rts", "sbc",
+            "sec", "sed", "sei",
+            "sta", "stx", "sty", "tax", "tay", "tsx", "txa", "txs", "tya",
+            "bra", "phx", "phy", "plx", "ply", "stz", "trb", "tsb", "bbr", "bbs",
+            "rmb", "smb", "stp", "wai")
+
+
+}

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

@@ -0,0 +1,60 @@
+package prog8.code.target.cx16
+
+import prog8.code.core.*
+
+
+class CX16Zeropage(options: CompilationOptions) : Zeropage(options) {
+
+    override val SCRATCH_B1 = 0x7au      // temp storage for a single byte
+    override val SCRATCH_REG = 0x7bu     // temp storage for a register, must be B1+1
+    override val SCRATCH_W1 = 0x7cu      // temp storage 1 for a word  $7c+$7d
+    override val SCRATCH_W2 = 0x7eu      // temp storage 2 for a word  $7e+$7f
+
+
+    init {
+        if (options.floats && options.zeropage !in arrayOf(
+                ZeropageType.FLOATSAFE,
+                ZeropageType.BASICSAFE,
+                ZeropageType.DONTUSE
+            ))
+            throw InternalCompilerException("when floats are enabled, zero page type should be 'floatsafe' or 'basicsafe' or 'dontuse'")
+
+        // the addresses 0x02 to 0x21 (inclusive) are taken for sixteen virtual 16-bit api registers.
+
+        synchronized(this) {
+            when (options.zeropage) {
+                ZeropageType.FULL -> {
+                    free.addAll(0x22u..0xffu)
+                }
+                ZeropageType.KERNALSAFE -> {
+                    free.addAll(0x22u..0x7fu)
+                    free.addAll(0xa9u..0xffu)
+                }
+                ZeropageType.FLOATSAFE -> {
+                    free.addAll(0x22u..0x7fu)
+                    free.addAll(0xd4u..0xffu)
+                }
+                ZeropageType.BASICSAFE -> {
+                    free.addAll(0x22u..0x7fu)
+                }
+                ZeropageType.DONTUSE -> {
+                    free.clear() // don't use zeropage at all
+                }
+                else -> throw InternalCompilerException("for this machine target, zero page type 'floatsafe' is not available. ${options.zeropage}")
+            }
+
+            removeReservedFromFreePool()
+
+            // note: the 16 virtual registers R0-R15 are not regular allocated variables, they're *memory mapped* elsewhere to fixed addresses.
+            // however, to be able for the compiler to "see" them as zero page variables, we have to register them here as well.
+            for(reg in 0..15) {
+                allocatedVariables[listOf("cx16", "r${reg}")]   = ZpAllocation((2+reg*2).toUInt(), DataType.UWORD, 2)        // cx16.r0 .. cx16.r15
+                allocatedVariables[listOf("cx16", "r${reg}s")]  = ZpAllocation((2+reg*2).toUInt(), DataType.WORD, 2)        // cx16.r0s .. cx16.r15s
+                allocatedVariables[listOf("cx16", "r${reg}L")]  = ZpAllocation((2+reg*2).toUInt(), DataType.UBYTE, 1)       // cx16.r0L .. cx16.r15L
+                allocatedVariables[listOf("cx16", "r${reg}H")]  = ZpAllocation((3+reg*2).toUInt(), DataType.UBYTE, 1)       // cx16.r0H .. cx16.r15H
+                allocatedVariables[listOf("cx16", "r${reg}sL")] = ZpAllocation((2+reg*2).toUInt(), DataType.BYTE, 1)       // cx16.r0sL .. cx16.r15sL
+                allocatedVariables[listOf("cx16", "r${reg}sH")] = ZpAllocation((3+reg*2).toUInt(), DataType.BYTE, 1)       // cx16.r0sH .. cx16.r15sH
+            }
+        }
+    }
+}

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

@@ -0,0 +1,48 @@
+package prog8.code.target.virtual
+
+import prog8.code.core.CompilationOptions
+import prog8.code.core.CpuType
+import prog8.code.core.IMachineDefinition
+import prog8.code.core.Zeropage
+import java.io.File
+import java.nio.file.Path
+
+
+class VirtualMachineDefinition: IMachineDefinition {
+
+    override val cpu = CpuType.VIRTUAL
+
+    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 PROGRAM_LOAD_ADDRESS = 0u      // not actually used
+
+    override val ESTACK_LO = 0u                 // not actually used
+    override val ESTACK_HI = 0u                 // not actually used
+
+    override lateinit var zeropage: Zeropage     // not actually used
+
+    override fun getFloat(num: Number) = TODO("float from number")
+
+    override fun importLibs(compilerOptions: CompilationOptions, compilationTargetName: String): List<String> {
+        return listOf("syslib")
+    }
+
+    override fun launchEmulator(selectedEmulator: Int, programNameWithPath: Path) {
+        println("\nStarting Virtual Machine...")
+        // to not have external module dependencies we launch the virtual machine via reflection
+        val vm = Class.forName("prog8.vm.VmRunner").getDeclaredConstructor().newInstance() as IVirtualMachineRunner
+        val source = File("$programNameWithPath.p8virt").readText()
+        vm.runProgram(source, true)
+    }
+
+    override fun isIOAddress(address: UInt): Boolean = false
+
+    override fun initializeZeropage(compilerOptions: CompilationOptions) {}
+
+    override val opcodeNames = emptySet<String>()
+}
+
+interface IVirtualMachineRunner {
+    fun runProgram(source: String, throttle: Boolean)
+}

codeGenCpu6502/build.gradle

@@ -0,0 +1,47 @@
+
+plugins {
+    id 'java'
+    id 'application'
+    id "org.jetbrains.kotlin.jvm"
+}
+
+java {
+    toolchain {
+        languageVersion = JavaLanguageVersion.of(javaVersion)
+    }
+}
+
+compileKotlin {
+    kotlinOptions {
+        jvmTarget = javaVersion
+    }
+}
+
+compileTestKotlin {
+    kotlinOptions {
+        jvmTarget = javaVersion
+    }
+}
+
+dependencies {
+    implementation project(':codeAst')
+    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:1.1.14"
+
+}
+
+sourceSets {
+    main {
+        java {
+            srcDirs = ["${project.projectDir}/src"]
+        }
+        resources {
+            srcDirs = ["${project.projectDir}/res"]
+        }
+    }
+}
+
+// note: there are no unit tests in this module!

codeGenCpu6502/codeGenCpu6502.iml

@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<module type="JAVA_MODULE" version="4">
+  <component name="NewModuleRootManager" inherit-compiler-output="true">
+    <exclude-output />
+    <content url="file://$MODULE_DIR$">
+      <sourceFolder url="file://$MODULE_DIR$/src" isTestSource="false" />
+      <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="codeAst" />
+    <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>

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

@@ -1,16 +1,16 @@
-package prog8.compiler.target.cpu6502.codegen
+package prog8.codegen.cpu6502
 
 import prog8.ast.Program
-import prog8.ast.base.VarDeclType
-import prog8.ast.expressions.NumericLiteralValue
+import prog8.ast.expressions.NumericLiteral
 import prog8.ast.statements.VarDecl
-import prog8.compilerinterface.IMachineDefinition
+import prog8.ast.statements.VarDeclType
+import prog8.code.core.IMachineDefinition
 
 
 // note: see https://wiki.nesdev.org/w/index.php/6502_assembly_optimisations
 
 
-fun optimizeAssembly(lines: MutableList<String>, machine: IMachineDefinition, program: Program): Int {
+internal fun optimizeAssembly(lines: MutableList<String>, machine: IMachineDefinition, program: Program): Int {
 
     var numberOfOptimizations = 0
 
@@ -64,6 +64,11 @@ fun optimizeAssembly(lines: MutableList<String>, machine: IMachineDefinition, pr
     return numberOfOptimizations
 }
 
+private fun String.isBranch() = this.startsWith("b")
+private fun String.isStoreReg() = this.startsWith("sta") || this.startsWith("sty") || this.startsWith("stx")
+private fun String.isStoreRegOrZero() = this.isStoreReg() || this.startsWith("stz")
+private fun String.isLoadReg() = this.startsWith("lda") || this.startsWith("ldy") || this.startsWith("ldx")
+
 private class Modification(val lineIndex: Int, val remove: Boolean, val replacement: String?)
 
 private fun apply(modifications: List<Modification>, lines: MutableList<String>) {
@@ -196,9 +201,9 @@ private fun optimizeSameAssignments(linesByFourteen: List<List<IndexedValue<Stri
         sta  A1
         sty  A2
          */
-        if(first.startsWith("st") && second.startsWith("st")
-            && third.startsWith("ld") && fourth.startsWith("ld")
-            && fifth.startsWith("st") && sixth.startsWith("st")) {
+        if(first.isStoreReg() && second.isStoreReg()
+            && third.isLoadReg() && fourth.isLoadReg()
+            && fifth.isStoreReg() && sixth.isStoreReg()) {
             val reg1 = first[2]
             val reg2 = second[2]
             val reg3 = third[2]
@@ -227,8 +232,8 @@ private fun optimizeSameAssignments(linesByFourteen: List<List<IndexedValue<Stri
         lda  A1     ; can be removed
         ldy  A2     ; can be removed if not followed by a branch instuction
          */
-        if(!overlappingMods && first.startsWith("st") && second.startsWith("st")
-            && third.startsWith("ld") && fourth.startsWith("ld")) {
+        if(!overlappingMods && first.isStoreReg() && second.isStoreReg()
+            && third.isLoadReg() && fourth.isLoadReg()) {
             val reg1 = first[2]
             val reg2 = second[2]
             val reg3 = third[2]
@@ -249,13 +254,14 @@ private fun optimizeSameAssignments(linesByFourteen: List<List<IndexedValue<Stri
                 }
             }
         }
+
         /*
         sta  A1
-        sty  A2
+        sty  A2     ; ... or stz
         lda  A1     ; can be removed if not followed by a branch instruction
          */
-        if(!overlappingMods && first.startsWith("st") && second.startsWith("st")
-            && third.startsWith("ld") && !fourth.startsWith("b")) {
+        if(!overlappingMods && first.isStoreReg() && second.isStoreRegOrZero()
+            && third.isLoadReg() && !fourth.isBranch()) {
             val reg1 = first[2]
             val reg3 = third[2]
             if(reg1==reg3) {
@@ -276,7 +282,7 @@ private fun optimizeSameAssignments(linesByFourteen: List<List<IndexedValue<Stri
         ldy  A1     ; make tay
         sta  A1     ; remove
          */
-        if(!overlappingMods && first.startsWith("sta") && second.startsWith("ld")
+        if(!overlappingMods && first.startsWith("sta") && second.isLoadReg()
             && third.startsWith("sta") && second.length>4) {
             val firstvalue = first.substring(4)
             val secondvalue = second.substring(4)
@@ -293,10 +299,10 @@ private fun optimizeSameAssignments(linesByFourteen: List<List<IndexedValue<Stri
         }
 
         /*
-        sta  A
-        sta  A
+        sta  A   ; or stz     double store, remove this first one
+        sta  A   ; or stz
          */
-        if(!overlappingMods && first.startsWith("st") && second.startsWith("st")) {
+        if(!overlappingMods && first.isStoreRegOrZero() && second.isStoreRegOrZero()) {
             if(first[2]==second[2]) {
                 val firstvalue = first.substring(4)
                 val secondvalue = second.substring(4)
@@ -304,7 +310,7 @@ private fun optimizeSameAssignments(linesByFourteen: List<List<IndexedValue<Stri
                     val address = getAddressArg(first, program)
                     if(address==null || !machine.isIOAddress(address)) {
                         overlappingMods = true
-                        mods.add(Modification(lines[1].index, true, null))
+                        mods.add(Modification(lines[0].index, true, null))
                     }
                 }
             }
@@ -333,7 +339,7 @@ private fun optimizeStoreLoadSame(linesByFour: List<List<IndexedValue<String>>>,
         ) {
             val third = lines[3].value.trimStart()
             val attemptRemove =
-                if(third.startsWith("b")) {
+                if(third.isBranch()) {
                     // a branch instruction follows, we can only remove the load instruction if
                     // another load instruction of the same register precedes the store instruction
                     // (otherwise wrong cpu flags are used)
@@ -400,7 +406,7 @@ private fun getAddressArg(line: String, program: Program): UInt? {
                     when(decl.type){
                         VarDeclType.VAR -> null
                         VarDeclType.CONST,
-                        VarDeclType.MEMORY -> (decl.value as NumericLiteralValue).number.toUInt()
+                        VarDeclType.MEMORY -> (decl.value as NumericLiteral).number.toUInt()
                     }
                 }
                 else null

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

@@ -1,13 +1,15 @@
-package prog8.compiler.target.cpu6502.codegen
+package prog8.codegen.cpu6502
 
-import prog8.ast.base.Cx16VirtualRegisters
-import prog8.ast.base.RegisterOrPair
-import prog8.ast.expressions.*
-import prog8.ast.statements.RegisterOrStatusflag
+import prog8.ast.expressions.ArrayIndexedExpression
+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
 
 
-internal fun asmsub6502ArgsEvalOrder(sub: Subroutine): List<Int> {
+fun asmsub6502ArgsEvalOrder(sub: Subroutine): List<Int> {
     val order = mutableListOf<Int>()
     // order is:
     //  1) cx16 virtual word registers,
@@ -35,7 +37,7 @@ internal fun asmsub6502ArgsEvalOrder(sub: Subroutine): List<Int> {
     return order
 }
 
-internal fun asmsub6502ArgsHaveRegisterClobberRisk(args: List<Expression>,
+fun asmsub6502ArgsHaveRegisterClobberRisk(args: List<Expression>,
                                                    paramRegisters: List<RegisterOrStatusflag>): Boolean {
     fun isClobberRisk(expr: Expression): Boolean {
         when (expr) {
@@ -44,10 +46,10 @@ internal fun asmsub6502ArgsHaveRegisterClobberRisk(args: List<Expression>,
                     it.registerOrPair in listOf(RegisterOrPair.Y, RegisterOrPair.AY, RegisterOrPair.XY)
                 }
             }
-            is FunctionCall -> {
-                if (expr.target.nameInSource == listOf("lsb") || expr.target.nameInSource == listOf("msb"))
+            is BuiltinFunctionCall -> {
+                if (expr.name == "lsb" || expr.name == "msb")
                     return isClobberRisk(expr.args[0])
-                if (expr.target.nameInSource == listOf("mkword"))
+                if (expr.name == "mkword")
                     return isClobberRisk(expr.args[0]) && isClobberRisk(expr.args[1])
                 return !expr.isSimple
             }

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

@@ -0,0 +1,146 @@
+package prog8.codegen.cpu6502
+
+import com.github.michaelbull.result.Ok
+import com.github.michaelbull.result.Result
+import com.github.michaelbull.result.mapError
+import prog8.code.core.*
+import java.io.File
+import java.nio.file.Path
+import kotlin.io.path.Path
+import kotlin.io.path.isRegularFile
+
+
+internal class AssemblyProgram(
+        override val name: String,
+        outputDir: Path,
+        private val compTarget: ICompilationTarget) : IAssemblyProgram {
+
+    private val assemblyFile = outputDir.resolve("$name.asm")
+    private val prgFile = outputDir.resolve("$name.prg")        // CBM prg executable program
+    private val xexFile = outputDir.resolve("$name.xex")        // Atari xex executable program
+    private val binFile = outputDir.resolve("$name.bin")
+    private val viceMonListFile = outputDir.resolve(viceMonListName(name))
+    private val listFile = outputDir.resolve("$name.list")
+
+    override fun assemble(options: CompilationOptions): Boolean {
+
+        val assemblerCommand: List<String>
+
+        when (compTarget.name) {
+            in setOf("c64", "c128", "cx16") -> {
+                // CBM machines .prg generation.
+
+                // add "-Wlong-branch"  to see warnings about conversion of branch instructions to jumps (default = do this silently)
+                val command = mutableListOf("64tass", "--ascii", "--case-sensitive", "--long-branch",
+                    "-Wall", "-Wno-strict-bool", "-Wno-shadow", // "-Werror",
+                    "--dump-labels", "--vice-labels", "--labels=$viceMonListFile", "--no-monitor"
+                )
+
+                if(options.asmQuiet)
+                    command.add("--quiet")
+
+                if(options.asmListfile)
+                    command.add("--list=$listFile")
+
+                val outFile = when (options.output) {
+                    OutputType.PRG -> {
+                        command.add("--cbm-prg")
+                        println("\nCreating prg for target ${compTarget.name}.")
+                        prgFile
+                    }
+                    OutputType.RAW -> {
+                        command.add("--nostart")
+                        println("\nCreating raw binary for target ${compTarget.name}.")
+                        binFile
+                    }
+                    else -> throw AssemblyError("invalid output type")
+                }
+                command.addAll(listOf("--output", outFile.toString(), assemblyFile.toString()))
+                assemblerCommand = command
+
+            }
+            "atari" -> {
+                // Atari800XL .xex generation.
+
+                // TODO are these options okay?
+                val command = mutableListOf("64tass", "--ascii", "--case-sensitive", "--long-branch",
+                    "-Wall", "-Wno-strict-bool", "-Wno-shadow", // "-Werror",
+                    "--no-monitor"
+                )
+
+                if(options.asmQuiet)
+                    command.add("--quiet")
+
+                if(options.asmListfile)
+                    command.add("--list=$listFile")
+
+                val outFile = when (options.output) {
+                    OutputType.XEX -> {
+                        command.add("--atari-xex")
+                        println("\nCreating xex for target ${compTarget.name}.")
+                        xexFile
+                    }
+                    OutputType.RAW -> {
+                        command.add("--nostart")
+                        println("\nCreating raw binary for target ${compTarget.name}.")
+                        binFile
+                    }
+                    else -> throw AssemblyError("invalid output type")
+                }
+                command.addAll(listOf("--output", outFile.toString(), assemblyFile.toString()))
+                assemblerCommand = command
+            }
+            else -> throw AssemblyError("invalid compilation target")
+        }
+
+        val proc = ProcessBuilder(assemblerCommand).inheritIO().start()
+        val result = proc.waitFor()
+        if (result == 0 && compTarget.name!="atari") {
+            removeGeneratedLabelsFromMonlist()
+            generateBreakpointList()
+        }
+        return result==0
+    }
+
+    private fun removeGeneratedLabelsFromMonlist() {
+        val pattern = Regex("""al (\w+) \S+${generatedLabelPrefix}.+?""")
+        val lines = viceMonListFile.toFile().readLines()
+        viceMonListFile.toFile().outputStream().bufferedWriter().use {
+            for (line in lines) {
+                if(pattern.matchEntire(line)==null)
+                    it.write(line+"\n")
+            }
+        }
+    }
+
+    private fun generateBreakpointList() {
+        // builds list of breakpoints, appends to monitor list file
+        val breakpoints = mutableListOf<String>()
+        val pattern = Regex("""al (\w+) \S+_prog8_breakpoint_\d+.?""")      // gather breakpoints by the source label that's generated for them
+        for (line in viceMonListFile.toFile().readLines()) {
+            val match = pattern.matchEntire(line)
+            if (match != null)
+                breakpoints.add("break \$" + match.groupValues[1])
+        }
+        val num = breakpoints.size
+        breakpoints.add(0, "; vice monitor breakpoint list now follows")
+        breakpoints.add(1, "; $num breakpoints have been defined")
+        breakpoints.add(2, "del")
+        viceMonListFile.toFile().appendText(breakpoints.joinToString("\n") + "\n")
+    }
+}
+
+
+internal fun loadAsmIncludeFile(filename: String, source: SourceCode): Result<String, NoSuchFileException> {
+    return if (filename.startsWith(SourceCode.libraryFilePrefix)) {
+        return com.github.michaelbull.result.runCatching {
+            SourceCode.Resource("/prog8lib/${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/BuiltinFunctionsAsmGen.kt

@@ -1,32 +1,73 @@
-package prog8.compiler.target.cpu6502.codegen
+package prog8.codegen.cpu6502
 
 import prog8.ast.IFunctionCall
 import prog8.ast.Node
 import prog8.ast.Program
-import prog8.ast.base.*
 import prog8.ast.expressions.*
 import prog8.ast.statements.ArrayIndex
+import prog8.ast.statements.BuiltinFunctionCallStatement
 import prog8.ast.statements.DirectMemoryWrite
-import prog8.ast.statements.FunctionCallStatement
 import prog8.ast.statements.Subroutine
-import prog8.ast.toHex
-import prog8.compiler.target.AssemblyError
-import prog8.compiler.target.Cx16Target
-import prog8.compiler.target.cpu6502.codegen.assignment.*
-import prog8.compilerinterface.CpuType
-import prog8.compilerinterface.FSignature
-import prog8.compilerinterface.subroutineFloatEvalResultVar2
+import prog8.code.core.*
+import prog8.codegen.cpu6502.assignment.*
+import prog8.compiler.BuiltinFunctions
+import prog8.compiler.FSignature
+import prog8.compiler.builtinFunctionReturnType
 
-internal class BuiltinFunctionsAsmGen(private val program: Program, private val asmgen: AsmGen, private val assignAsmGen: AssignmentAsmGen) {
 
-    internal fun translateFunctioncallExpression(fcall: FunctionCall, func: FSignature, resultToStack: Boolean, resultRegister: RegisterOrPair?) {
+internal class BuiltinFunctionsAsmGen(private val program: Program,
+                                      private val asmgen: AsmGen,
+                                      private val assignAsmGen: AssignmentAsmGen,
+                                      private val allocations: VariableAllocator) {
+
+    internal fun translateFunctioncallExpression(fcall: BuiltinFunctionCall, resultToStack: Boolean, resultRegister: RegisterOrPair?) {
+        val func = BuiltinFunctions.getValue(fcall.target.nameInSource.single())
         translateFunctioncall(fcall, func, discardResult = false, resultToStack = resultToStack, resultRegister = resultRegister)
     }
 
-    internal fun translateFunctioncallStatement(fcall: FunctionCallStatement, func: FSignature) {
+    internal fun translateFunctioncallStatement(fcall: BuiltinFunctionCallStatement) {
+        val func = BuiltinFunctions.getValue(fcall.name)
         translateFunctioncall(fcall, func, discardResult = true, resultToStack = false, resultRegister = null)
     }
 
+    internal fun translateFunctionCallWithFirstArg(bfc: IFunctionCall, singleArg: AsmAssignSource, isStatement: Boolean, scope: Subroutine): DataType {
+        val name = bfc.target.nameInSource.single()
+        val func = BuiltinFunctions.getValue(name)
+        val argExpression =
+            when(singleArg.kind) {
+                SourceStorageKind.LITERALNUMBER -> singleArg.number!!
+                SourceStorageKind.EXPRESSION -> singleArg.expression!!
+                SourceStorageKind.ARRAY -> singleArg.array!!
+                else -> {
+                    // TODO make it so that we can assign efficiently from something else as an expression....namely: register(s)
+                    //      this is useful in pipe expressions for instance, to skip the use of a temporary variable
+                    //      but for now, just assign it to a temporary variable and use that as a source
+                    //      Idea: to do this without having to rewrite every single function in translateFunctioncall(),
+                    //            hack a special IdentifierReference like "!6502.A/X/Y/AX/AY/XY" to reference a cpu register
+                    val tempvar = asmgen.getTempVarName(singleArg.datatype)
+                    val assignTempvar = AsmAssignment(
+                        singleArg,
+                        AsmAssignTarget(TargetStorageKind.VARIABLE, program, asmgen, singleArg.datatype, scope, variableAsmName = asmgen.asmVariableName(tempvar)),
+                        false, program.memsizer, Position.DUMMY
+                    )
+                    assignAsmGen.translateNormalAssignment(assignTempvar)
+                    // now use an expression to assign this tempvar
+                    val ident = IdentifierReference(tempvar, Position.DUMMY)
+                    ident.linkParents(scope)
+                    ident
+                }
+            }
+        val argExpressions = mutableListOf(argExpression)
+        val fcall = BuiltinFunctionCall(IdentifierReference(listOf(name), Position.DUMMY), argExpressions, Position.DUMMY)
+        fcall.linkParents(scope)
+        translateFunctioncall(fcall, func, discardResult = false, resultToStack = false, null)
+        return if(isStatement) {
+            DataType.UNDEFINED
+        } else {
+            builtinFunctionReturnType(func.name).getOrElse { throw AssemblyError("unknown dt") }
+        }
+    }
+
     private fun translateFunctioncall(fcall: IFunctionCall, func: FSignature, discardResult: Boolean, resultToStack: Boolean, resultRegister: RegisterOrPair?) {
         if (discardResult && func.pure)
             return  // can just ignore the whole function call altogether
@@ -42,18 +83,8 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
             "mkword" -> funcMkword(fcall, resultToStack, resultRegister)
             "abs" -> funcAbs(fcall, func, resultToStack, resultRegister, sscope)
             "swap" -> funcSwap(fcall)
-            "min", "max" -> funcMinMax(fcall, func, resultToStack, resultRegister, sscope)
-            "sum" -> funcSum(fcall, resultToStack, resultRegister, sscope)
             "any", "all" -> funcAnyAll(fcall, func, resultToStack, resultRegister, sscope)
-            "sin8", "sin8u", "sin16", "sin16u",
-            "sinr8", "sinr8u", "sinr16", "sinr16u",
-            "cos8", "cos8u", "cos16", "cos16u",
-            "cosr8", "cosr8u", "cosr16", "cosr16u" -> funcSinCosInt(fcall, func, resultToStack, resultRegister, sscope)
             "sgn" -> funcSgn(fcall, func, resultToStack, resultRegister, sscope)
-            "sin", "cos", "tan", "atan",
-            "ln", "log2", "sqrt", "rad",
-            "deg", "round", "floor", "ceil",
-            "rndf" -> funcVariousFloatFuncs(fcall, func, resultToStack, resultRegister, sscope)
             "rnd", "rndw" -> funcRnd(func, resultToStack, resultRegister, sscope)
             "sqrt16" -> funcSqrt16(fcall, func, resultToStack, resultRegister, sscope)
             "rol" -> funcRol(fcall)
@@ -66,9 +97,22 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
             "peekw" -> funcPeekW(fcall, resultToStack, resultRegister)
             "peek" -> throw AssemblyError("peek() should have been replaced by @()")
             "pokew" -> funcPokeW(fcall)
+            "pokemon" -> { /* meme function */ }
             "poke" -> throw AssemblyError("poke() should have been replaced by @()")
-            "push", "pushw" -> funcPush(fcall, func)
-            "pop", "popw" -> funcPop(fcall, func)
+            "push" -> asmgen.pushCpuStack(DataType.UBYTE, fcall.args[0])
+            "pushw" -> asmgen.pushCpuStack(DataType.UWORD, fcall.args[0])
+            "pop" -> {
+                require(fcall.args[0] is IdentifierReference) {
+                    "attempt to pop a value into a differently typed variable, or in something else that isn't supported ${(fcall as Node).position}"
+                }
+                asmgen.popCpuStack(DataType.UBYTE, (fcall.args[0] as IdentifierReference).targetVarDecl(program)!!, (fcall as Node).definingSubroutine)
+            }
+            "popw" -> {
+                require(fcall.args[0] is IdentifierReference) {
+                    "attempt to pop a value into a differently typed variable, or in something else that isn't supported ${(fcall as Node).position}"
+                }
+                asmgen.popCpuStack(DataType.UWORD, (fcall.args[0] as IdentifierReference).targetVarDecl(program)!!, (fcall as Node).definingSubroutine)
+            }
             "rsave" -> funcRsave()
             "rsavex" -> funcRsaveX()
             "rrestore" -> funcRrestore()
@@ -131,119 +175,8 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
             asmgen.out("  sta  P8ZP_SCRATCH_B1 |  pla |  tax |  lda  P8ZP_SCRATCH_B1")
     }
 
-    private fun funcPop(fcall: IFunctionCall, func: FSignature) {
-        // note: because A is pushed first so popped last, saving A is often not required here.
-        require(fcall.args[0] is IdentifierReference) {
-            "attempt to pop a value into a differently typed variable, or in something else that isn't supported ${(fcall as Node).position}"
-        }
-        val target = (fcall.args[0] as IdentifierReference).targetVarDecl(program)!!
-        val parameter = target.subroutineParameter
-        if(parameter!=null) {
-            val sub = parameter.definingSubroutine!!
-            require(sub.isAsmSubroutine) {
-                "push/pop arg passing only supported on asmsubs ${(fcall as Node).position}"
-            }
-            val shouldKeepA = sub.asmParameterRegisters.any { it.registerOrPair==RegisterOrPair.AX || it.registerOrPair==RegisterOrPair.AY }
-            val reg = sub.asmParameterRegisters[sub.parameters.indexOf(parameter)]
-            if(reg.statusflag!=null) {
-                if(shouldKeepA)
-                    asmgen.out("  sta  P8ZP_SCRATCH_REG")
-                asmgen.out("""
-                    clc
-                    pla
-                    beq  +
-                    sec
-+""")
-                if(shouldKeepA)
-                    asmgen.out("  lda  P8ZP_SCRATCH_REG")
-            }
-            else {
-                if (func.name == "pop") {
-                    if (asmgen.isTargetCpu(CpuType.CPU65c02)) {
-                        when (reg.registerOrPair) {
-                            RegisterOrPair.A -> asmgen.out("  pla")
-                            RegisterOrPair.X -> asmgen.out("  plx")
-                            RegisterOrPair.Y -> asmgen.out("  ply")
-                            in Cx16VirtualRegisters -> asmgen.out("  pla |  sta  cx16.${reg.registerOrPair!!.name.lowercase()}")
-                            else -> throw AssemblyError("invalid target register ${reg.registerOrPair}")
-                        }
-                    } else {
-                        when (reg.registerOrPair) {
-                            RegisterOrPair.A -> asmgen.out("  pla")
-                            RegisterOrPair.X -> {
-                                if(shouldKeepA)
-                                    asmgen.out("  sta  P8ZP_SCRATCH_REG |  pla |  tax |  lda  P8ZP_SCRATCH_REG")
-                                else
-                                    asmgen.out("  pla |  tax")
-                            }
-                            RegisterOrPair.Y -> {
-                                if(shouldKeepA)
-                                    asmgen.out("  sta  P8ZP_SCRATCH_REG |  pla |  tay |  lda  P8ZP_SCRATCH_REG")
-                                else
-                                    asmgen.out("  pla |  tay")
-                            }
-                            in Cx16VirtualRegisters -> asmgen.out("  pla |  sta  cx16.${reg.registerOrPair!!.name.lowercase()}")
-                            else -> throw AssemblyError("invalid target register ${reg.registerOrPair}")
-                        }
-                    }
-                } else {
-                    // word pop
-                    if (asmgen.isTargetCpu(CpuType.CPU65c02))
-                        when (reg.registerOrPair) {
-                            RegisterOrPair.AX -> asmgen.out("  plx |  pla")
-                            RegisterOrPair.AY -> asmgen.out("  ply |  pla")
-                            RegisterOrPair.XY -> asmgen.out("  ply |  plx")
-                            in Cx16VirtualRegisters -> {
-                                val regname = reg.registerOrPair!!.name.lowercase()
-                                asmgen.out("  pla |  sta  cx16.$regname+1 |  pla |  sta  cx16.$regname")
-                            }
-                            else -> throw AssemblyError("invalid target register ${reg.registerOrPair}")
-                        }
-                    else {
-                        when (reg.registerOrPair) {
-                            RegisterOrPair.AX -> asmgen.out("  pla |  tax |  pla")
-                            RegisterOrPair.AY -> asmgen.out("  pla |  tay |  pla")
-                            RegisterOrPair.XY -> asmgen.out("  pla |  tay |  pla |  tax")
-                            in Cx16VirtualRegisters -> {
-                                val regname = reg.registerOrPair!!.name.lowercase()
-                                asmgen.out("  pla |  sta  cx16.$regname+1 |  pla |  sta  cx16.$regname")
-                            }
-                            else -> throw AssemblyError("invalid target register ${reg.registerOrPair}")
-                        }
-                    }
-                }
-            }
-        } else {
-            val tgt = AsmAssignTarget(TargetStorageKind.VARIABLE, program, asmgen, target.datatype, (fcall as Node).definingSubroutine, variableAsmName = asmgen.asmVariableName(target.name))
-            if (func.name == "pop") {
-                asmgen.out("  pla")
-                asmgen.assignRegister(RegisterOrPair.A, tgt)
-            } else {
-                if (asmgen.isTargetCpu(CpuType.CPU65c02))
-                    asmgen.out("  ply |  pla")
-                else
-                    asmgen.out("  pla |  tay |  pla")
-                asmgen.assignRegister(RegisterOrPair.AY, tgt)
-            }
-        }
-    }
-
-    private fun funcPush(fcall: IFunctionCall, func: FSignature) {
-        val signed = fcall.args[0].inferType(program).oneOf(DataType.BYTE, DataType.WORD)
-        if(func.name=="push") {
-            asmgen.assignExpressionToRegister(fcall.args[0], RegisterOrPair.A, signed)
-            asmgen.out("  pha")
-        } else {
-            asmgen.assignExpressionToRegister(fcall.args[0], RegisterOrPair.AY, signed)
-            if (asmgen.isTargetCpu(CpuType.CPU65c02))
-                asmgen.out("  pha |  phy")
-            else
-                asmgen.out("  pha |  tya |  pha")
-        }
-    }
-
     private fun funcCallFar(fcall: IFunctionCall) {
-        if(asmgen.options.compTarget !is Cx16Target)
+        if(asmgen.options.compTarget.name != "cx16")
             throw AssemblyError("callfar only works on cx16 target at this time")
 
         val bank = fcall.args[0].constValue(program)?.number?.toInt()
@@ -274,7 +207,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                         .byte  ${bank.toHex()}
                         sta  ${asmgen.asmVariableName(argAddrArg.identifier)}""")
                 }
-                is NumericLiteralValue -> {
+                is NumericLiteral -> {
                     asmgen.out("""
                         lda  ${argAddrArg.number.toHex()}
                         jsr  cx16.jsrfar
@@ -288,7 +221,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
     }
 
     private fun funcCallRom(fcall: IFunctionCall) {
-        if(asmgen.options.compTarget !is Cx16Target)
+        if(asmgen.options.compTarget.name != "cx16")
             throw AssemblyError("callrom only works on cx16 target at this time")
 
         val bank = fcall.args[0].constValue(program)?.number?.toInt()
@@ -327,7 +260,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                         pla
                         sta  $01""")
                 }
-                is NumericLiteralValue -> {
+                is NumericLiteral -> {
                     asmgen.out("""
                         lda  $01
                         pha
@@ -347,8 +280,8 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
     private fun funcCmp(fcall: IFunctionCall) {
         val arg1 = fcall.args[0]
         val arg2 = fcall.args[1]
-        val dt1 = arg1.inferType(program).getOr(DataType.UNDEFINED)
-        val dt2 = arg2.inferType(program).getOr(DataType.UNDEFINED)
+        val dt1 = arg1.inferType(program).getOrElse { throw AssemblyError("unknown dt") }
+        val dt2 = arg2.inferType(program).getOrElse { throw AssemblyError("unknown dt") }
         if(dt1 in ByteDatatypes) {
             if(dt2 in ByteDatatypes) {
                 when (arg2) {
@@ -356,12 +289,12 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                         asmgen.assignExpressionToRegister(arg1, RegisterOrPair.A)
                         asmgen.out("  cmp  ${asmgen.asmVariableName(arg2)}")
                     }
-                    is NumericLiteralValue -> {
+                    is NumericLiteral -> {
                         asmgen.assignExpressionToRegister(arg1, RegisterOrPair.A)
-                        asmgen.out("  cmp  #${arg2.number}")
+                        asmgen.out("  cmp  #${arg2.number.toInt()}")
                     }
                     is DirectMemoryRead -> {
-                        if(arg2.addressExpression is NumericLiteralValue) {
+                        if(arg2.addressExpression is NumericLiteral) {
                             asmgen.assignExpressionToRegister(arg1, RegisterOrPair.A)
                             asmgen.out("  cmp  ${arg2.addressExpression.constValue(program)!!.number.toHex()}")
                         } else {
@@ -390,12 +323,12 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                             cmp  ${asmgen.asmVariableName(arg2)}
 +""")
                     }
-                    is NumericLiteralValue -> {
+                    is NumericLiteral -> {
                         asmgen.assignExpressionToRegister(arg1, RegisterOrPair.AY)
                         asmgen.out("""
-                            cpy  #>${arg2.number}
+                            cpy  #>${arg2.number.toInt()}
                             bne  +
-                            cmp  #<${arg2.number}
+                            cmp  #<${arg2.number.toInt()}
 +""")
                     }
                     else -> {
@@ -414,15 +347,16 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
     }
 
     private fun funcMemory(fcall: IFunctionCall, discardResult: Boolean, resultToStack: Boolean, resultRegister: RegisterOrPair?) {
-        if(discardResult || fcall !is FunctionCall)
+        if(discardResult || fcall !is BuiltinFunctionCall)
             throw AssemblyError("should not discard result of memory allocation at $fcall")
-        val nameRef = fcall.args[0] as IdentifierReference
-        val name = (nameRef.targetVarDecl(program)!!.value as StringLiteralValue).value
-        val size = (fcall.args[1] as NumericLiteralValue).number.toUInt()
+        val name = (fcall.args[0] as StringLiteral).value
+        require(name.all { it.isLetterOrDigit() || it=='_' }) {"memory name should be a valid symbol name"}
+        val size = (fcall.args[1] as NumericLiteral).number.toUInt()
+        val align = (fcall.args[2] as NumericLiteral).number.toUInt()
 
-        val existingSize = asmgen.slabs[name]
-        if(existingSize!=null && existingSize!=size)
-            throw AssemblyError("memory slab '$name' already exists with a different size ($size) at ${fcall.position}")
+        val existing = allocations.getMemorySlab(name)
+        if(existing!=null && (existing.first!=size || existing.second!=align))
+            throw AssemblyError("memory slab '$name' already exists with a different size or alignment at ${fcall.position}")
 
         val slabname = IdentifierReference(listOf("prog8_slabs", name), fcall.position)
         slabname.linkParents(fcall)
@@ -434,7 +368,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                 AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.AY, false, null, program, asmgen)
         val assign = AsmAssignment(src, target, false, program.memsizer, fcall.position)
         asmgen.translateNormalAssignment(assign)
-        asmgen.slabs[name] = size
+        allocations.allocateMemorySlab(name, size, align)
     }
 
     private fun funcSqrt16(fcall: IFunctionCall, func: FSignature, resultToStack: Boolean, resultRegister: RegisterOrPair?, scope: Subroutine?) {
@@ -447,23 +381,6 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
         }
     }
 
-    private fun funcSinCosInt(fcall: IFunctionCall, func: FSignature, resultToStack: Boolean, resultRegister: RegisterOrPair?, scope: Subroutine?) {
-        translateArguments(fcall.args, func, scope)
-        if(resultToStack)
-            asmgen.out("  jsr  prog8_lib.func_${func.name}_stack")
-        else
-            when(func.name) {
-                "sin8", "sin8u", "sinr8", "sinr8u", "cos8", "cos8u", "cosr8", "cosr8u" -> {
-                    asmgen.out("  jsr  prog8_lib.func_${func.name}_into_A")
-                    assignAsmGen.assignRegisterByte(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.A, false, scope, program, asmgen), CpuRegister.A)
-                }
-                "sin16", "sin16u", "sinr16", "sinr16u", "cos16", "cos16u", "cosr16", "cosr16u" -> {
-                    asmgen.out("  jsr  prog8_lib.func_${func.name}_into_AY")
-                    assignAsmGen.assignRegisterpairWord(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.AY, false, scope, program, asmgen), RegisterOrPair.AY)
-                }
-            }
-    }
-
     private fun funcReverse(fcall: IFunctionCall) {
         val variable = fcall.args.single()
         if (variable is IdentifierReference) {
@@ -546,8 +463,8 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                         asmgen.out("  jsr  prog8_lib.ror2_array_ub")
                     }
                     is DirectMemoryRead -> {
-                        if (what.addressExpression is NumericLiteralValue) {
-                            val number = (what.addressExpression as NumericLiteralValue).number
+                        if (what.addressExpression is NumericLiteral) {
+                            val number = (what.addressExpression as NumericLiteral).number
                             asmgen.out("  lda  ${number.toHex()} |  lsr  a |  bcc  + |  ora  #\$80 |+  |  sta  ${number.toHex()}")
                         } else {
                             asmgen.assignExpressionToRegister(what.addressExpression, RegisterOrPair.AY)
@@ -589,14 +506,14 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                         asmgen.out("  jsr  prog8_lib.ror_array_ub")
                     }
                     is DirectMemoryRead -> {
-                        if (what.addressExpression is NumericLiteralValue) {
-                            val number = (what.addressExpression as NumericLiteralValue).number
+                        if (what.addressExpression is NumericLiteral) {
+                            val number = (what.addressExpression as NumericLiteral).number
                             asmgen.out("  ror  ${number.toHex()}")
                         } else {
                             val ptrAndIndex = asmgen.pointerViaIndexRegisterPossible(what.addressExpression)
                             if(ptrAndIndex!=null) {
                                 asmgen.assignExpressionToRegister(ptrAndIndex.second, RegisterOrPair.X)
-                                asmgen.saveRegisterLocal(CpuRegister.X, (fcall as FunctionCallStatement).definingSubroutine!!)
+                                asmgen.saveRegisterLocal(CpuRegister.X, (fcall as Node).definingSubroutine!!)
                                 asmgen.assignExpressionToRegister(ptrAndIndex.first, RegisterOrPair.AY)
                                 asmgen.restoreRegisterLocal(CpuRegister.X)
                                 asmgen.out("""
@@ -647,8 +564,8 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                         asmgen.out("  jsr  prog8_lib.rol2_array_ub")
                     }
                     is DirectMemoryRead -> {
-                        if (what.addressExpression is NumericLiteralValue) {
-                            val number = (what.addressExpression as NumericLiteralValue).number
+                        if (what.addressExpression is NumericLiteral) {
+                            val number = (what.addressExpression as NumericLiteral).number
                             asmgen.out("  lda  ${number.toHex()} |  cmp  #\$80 |  rol  a |  sta  ${number.toHex()}")
                         } else {
                             asmgen.assignExpressionToRegister(what.addressExpression, RegisterOrPair.AY)
@@ -690,14 +607,14 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                         asmgen.out("  jsr  prog8_lib.rol_array_ub")
                     }
                     is DirectMemoryRead -> {
-                        if (what.addressExpression is NumericLiteralValue) {
-                            val number = (what.addressExpression as NumericLiteralValue).number
+                        if (what.addressExpression is NumericLiteral) {
+                            val number = (what.addressExpression as NumericLiteral).number
                             asmgen.out("  rol  ${number.toHex()}")
                         } else {
                             val ptrAndIndex = asmgen.pointerViaIndexRegisterPossible(what.addressExpression)
                             if(ptrAndIndex!=null) {
                                 asmgen.assignExpressionToRegister(ptrAndIndex.second, RegisterOrPair.X)
-                                asmgen.saveRegisterLocal(CpuRegister.X, (fcall as FunctionCallStatement).definingSubroutine!!)
+                                asmgen.saveRegisterLocal(CpuRegister.X, (fcall as Node).definingSubroutine!!)
                                 asmgen.assignExpressionToRegister(ptrAndIndex.first, RegisterOrPair.AY)
                                 asmgen.restoreRegisterLocal(CpuRegister.X)
                                 asmgen.out("""
@@ -742,16 +659,6 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
         asmgen.assignExpressionToVariable(indexer.indexExpr, "prog8_lib.${operation}_array_u${dt}._arg_index", DataType.UBYTE, null)
     }
 
-    private fun funcVariousFloatFuncs(fcall: IFunctionCall, func: FSignature, resultToStack: Boolean, resultRegister: RegisterOrPair?, scope: Subroutine?) {
-        translateArguments(fcall.args, func, scope)
-        if(resultToStack)
-            asmgen.out("  jsr  floats.func_${func.name}_stack")
-        else {
-            asmgen.out("  jsr  floats.func_${func.name}_fac1")
-            assignAsmGen.assignFAC1float(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.FAC1, true, scope, program, asmgen))
-        }
-    }
-
     private fun funcSgn(fcall: IFunctionCall, func: FSignature, resultToStack: Boolean, resultRegister: RegisterOrPair?, scope: Subroutine?) {
         translateArguments(fcall.args, func, scope)
         val dt = fcall.args.single().inferType(program)
@@ -789,92 +696,15 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
             }
         } else {
             when (dt.getOr(DataType.UNDEFINED)) {
-                DataType.ARRAY_B, DataType.ARRAY_UB, DataType.STR -> asmgen.out("  jsr  prog8_lib.func_${function.name}_b_into_A")
-                DataType.ARRAY_UW, DataType.ARRAY_W -> asmgen.out("  jsr  prog8_lib.func_${function.name}_w_into_A")
-                DataType.ARRAY_F -> asmgen.out("  jsr  floats.func_${function.name}_f_into_A")
+                DataType.ARRAY_B, DataType.ARRAY_UB, DataType.STR -> asmgen.out("  jsr  prog8_lib.func_${function.name}_b_into_A |  ldy  #0")
+                DataType.ARRAY_UW, DataType.ARRAY_W -> asmgen.out("  jsr  prog8_lib.func_${function.name}_w_into_A |  ldy  #0")
+                DataType.ARRAY_F -> asmgen.out("  jsr  floats.func_${function.name}_f_into_A |  ldy  #0")
                 else -> throw AssemblyError("weird type $dt")
             }
             assignAsmGen.assignRegisterByte(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.A, false, scope, program, asmgen), CpuRegister.A)
         }
     }
 
-    private fun funcMinMax(fcall: IFunctionCall, function: FSignature, resultToStack: Boolean, resultRegister: RegisterOrPair?, scope: Subroutine?) {
-        outputAddressAndLenghtOfArray(fcall.args[0])
-        val dt = fcall.args.single().inferType(program)
-        if(resultToStack) {
-            when (dt.getOr(DataType.UNDEFINED)) {
-                DataType.ARRAY_UB, DataType.STR -> asmgen.out("  jsr  prog8_lib.func_${function.name}_ub_stack")
-                DataType.ARRAY_B -> asmgen.out("  jsr  prog8_lib.func_${function.name}_b_stack")
-                DataType.ARRAY_UW -> asmgen.out("  jsr  prog8_lib.func_${function.name}_uw_stack")
-                DataType.ARRAY_W -> asmgen.out("  jsr  prog8_lib.func_${function.name}_w_stack")
-                DataType.ARRAY_F -> asmgen.out("  jsr  floats.func_${function.name}_f_stack")
-                else -> throw AssemblyError("weird type $dt")
-            }
-        } else {
-            when (dt.getOr(DataType.UNDEFINED)) {
-                DataType.ARRAY_UB, DataType.STR -> {
-                    asmgen.out("  jsr  prog8_lib.func_${function.name}_ub_into_A")
-                    assignAsmGen.assignRegisterByte(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.A, false, scope, program, asmgen), CpuRegister.A)
-                }
-                DataType.ARRAY_B -> {
-                    asmgen.out("  jsr  prog8_lib.func_${function.name}_b_into_A")
-                    assignAsmGen.assignRegisterByte(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.A, false, scope, program, asmgen), CpuRegister.A)
-                }
-                DataType.ARRAY_UW -> {
-                    asmgen.out("  jsr  prog8_lib.func_${function.name}_uw_into_AY")
-                    assignAsmGen.assignRegisterpairWord(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.AY, false, scope, program, asmgen), RegisterOrPair.AY)
-                }
-                DataType.ARRAY_W -> {
-                    asmgen.out("  jsr  prog8_lib.func_${function.name}_w_into_AY")
-                    assignAsmGen.assignRegisterpairWord(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.AY, false, scope, program, asmgen), RegisterOrPair.AY)
-                }
-                DataType.ARRAY_F -> {
-                    asmgen.out("  jsr  floats.func_${function.name}_f_fac1")
-                    assignAsmGen.assignFAC1float(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.FAC1, true, scope, program, asmgen))
-                }
-                else -> throw AssemblyError("weird type $dt")
-            }
-        }
-    }
-
-    private fun funcSum(fcall: IFunctionCall, resultToStack: Boolean, resultRegister: RegisterOrPair?, scope: Subroutine?) {
-        outputAddressAndLenghtOfArray(fcall.args[0])
-        val dt = fcall.args.single().inferType(program)
-        if(resultToStack) {
-            when (dt.getOr(DataType.UNDEFINED)) {
-                DataType.ARRAY_UB, DataType.STR -> asmgen.out("  jsr  prog8_lib.func_sum_ub_stack")
-                DataType.ARRAY_B -> asmgen.out("  jsr  prog8_lib.func_sum_b_stack")
-                DataType.ARRAY_UW -> asmgen.out("  jsr  prog8_lib.func_sum_uw_stack")
-                DataType.ARRAY_W -> asmgen.out("  jsr  prog8_lib.func_sum_w_stack")
-                DataType.ARRAY_F -> asmgen.out("  jsr  floats.func_sum_f_stack")
-                else -> throw AssemblyError("weird type $dt")
-            }
-        } else {
-            when (dt.getOr(DataType.UNDEFINED)) {
-                DataType.ARRAY_UB, DataType.STR -> {
-                    asmgen.out("  jsr  prog8_lib.func_sum_ub_into_AY")
-                    assignAsmGen.assignRegisterpairWord(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.AY, false, scope, program, asmgen), RegisterOrPair.AY)
-                }
-                DataType.ARRAY_B -> {
-                    asmgen.out("  jsr  prog8_lib.func_sum_b_into_AY")
-                    assignAsmGen.assignRegisterpairWord(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.AY, false, scope, program, asmgen), RegisterOrPair.AY)
-                }
-                DataType.ARRAY_UW -> {
-                    asmgen.out("  jsr  prog8_lib.func_sum_uw_into_AY")
-                    assignAsmGen.assignRegisterpairWord(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.AY, false, scope, program, asmgen), RegisterOrPair.AY)
-                }
-                DataType.ARRAY_W -> {
-                    asmgen.out("  jsr  prog8_lib.func_sum_w_into_AY")
-                    assignAsmGen.assignRegisterpairWord(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.AY, false, scope, program, asmgen), RegisterOrPair.AY)
-                }
-                DataType.ARRAY_F -> {
-                    asmgen.out("  jsr  floats.func_sum_f_fac1")
-                    assignAsmGen.assignFAC1float(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.FAC1, true, scope, program, asmgen))
-                }
-                else -> throw AssemblyError("weird type $dt")
-            }
-        }
-    }
 
     private fun funcSwap(fcall: IFunctionCall) {
         val first = fcall.args[0]
@@ -920,8 +750,8 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
 
         // optimized simple case: swap two memory locations
         if(first is DirectMemoryRead && second is DirectMemoryRead) {
-            val addr1 = (first.addressExpression as? NumericLiteralValue)?.number?.toHex()
-            val addr2 = (second.addressExpression as? NumericLiteralValue)?.number?.toHex()
+            val addr1 = (first.addressExpression as? NumericLiteral)?.number?.toHex()
+            val addr2 = (second.addressExpression as? NumericLiteral)?.number?.toHex()
             val name1 = if(first.addressExpression is IdentifierReference) asmgen.asmVariableName(first.addressExpression as IdentifierReference) else null
             val name2 = if(second.addressExpression is IdentifierReference) asmgen.asmVariableName(second.addressExpression as IdentifierReference) else null
 
@@ -952,10 +782,10 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                         if(pointerVariable != null
                             && pointerVariable isSameAs secondExpr.left
                             && firstExpr.operator == "+" && secondExpr.operator == "+"
-                            && (firstOffset is NumericLiteralValue || firstOffset is IdentifierReference || firstOffset is TypecastExpression)
-                            && (secondOffset is NumericLiteralValue || secondOffset is IdentifierReference || secondOffset is TypecastExpression)
+                            && (firstOffset is NumericLiteral || firstOffset is IdentifierReference || firstOffset is TypecastExpression)
+                            && (secondOffset is NumericLiteral || secondOffset is IdentifierReference || secondOffset is TypecastExpression)
                         ) {
-                            if(firstOffset is NumericLiteralValue && secondOffset is NumericLiteralValue) {
+                            if(firstOffset is NumericLiteral && secondOffset is NumericLiteral) {
                                 if(firstOffset!=secondOffset) {
                                     swapArrayValues(
                                         DataType.UBYTE,
@@ -992,13 +822,11 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
             val arrayVarName1 = asmgen.asmVariableName(first.arrayvar)
             val arrayVarName2 = asmgen.asmVariableName(second.arrayvar)
             val elementIDt = first.inferType(program)
-            if(!elementIDt.isKnown)
-                throw AssemblyError("unknown dt")
-            val elementDt = elementIDt.getOr(DataType.UNDEFINED)
+            val elementDt = elementIDt.getOrElse { throw AssemblyError("unknown dt") }
 
-            val firstNum = first.indexer.indexExpr as? NumericLiteralValue
+            val firstNum = first.indexer.indexExpr as? NumericLiteral
             val firstVar = first.indexer.indexExpr as? IdentifierReference
-            val secondNum = second.indexer.indexExpr as? NumericLiteralValue
+            val secondNum = second.indexer.indexExpr as? NumericLiteral
             val secondVar = second.indexer.indexExpr as? IdentifierReference
 
             if(firstNum!=null && secondNum!=null) {
@@ -1067,7 +895,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
         }
     }
 
-    private fun swapArrayValues(elementDt: DataType, arrayVarName1: String, indexValue1: NumericLiteralValue, arrayVarName2: String, indexValue2: NumericLiteralValue) {
+    private fun swapArrayValues(elementDt: DataType, arrayVarName1: String, indexValue1: NumericLiteral, arrayVarName2: String, indexValue2: NumericLiteral) {
         val index1 = indexValue1.number.toInt() * program.memsizer.memorySize(elementDt)
         val index2 = indexValue2.number.toInt() * program.memsizer.memorySize(elementDt)
         when(elementDt) {
@@ -1181,7 +1009,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
         }
     }
 
-    private fun swapArrayValues(elementDt: DataType, arrayVarName1: String, indexValue1: NumericLiteralValue, arrayVarName2: String, indexName2: IdentifierReference) {
+    private fun swapArrayValues(elementDt: DataType, arrayVarName1: String, indexValue1: NumericLiteral, arrayVarName2: String, indexName2: IdentifierReference) {
         val index1 = indexValue1.number.toInt() * program.memsizer.memorySize(elementDt)
         val idxAsmName2 = asmgen.asmVariableName(indexName2)
         when(elementDt) {
@@ -1239,7 +1067,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
         }
     }
 
-    private fun swapArrayValues(elementDt: DataType, arrayVarName1: String, indexName1: IdentifierReference, arrayVarName2: String, indexValue2: NumericLiteralValue) {
+    private fun swapArrayValues(elementDt: DataType, arrayVarName1: String, indexName1: IdentifierReference, arrayVarName2: String, indexValue2: NumericLiteral) {
         val idxAsmName1 = asmgen.asmVariableName(indexName1)
         val index2 = indexValue2.number.toInt() * program.memsizer.memorySize(elementDt)
         when(elementDt) {
@@ -1302,27 +1130,21 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
         val dt = fcall.args.single().inferType(program).getOr(DataType.UNDEFINED)
         if(resultToStack) {
             when (dt) {
-                in ByteDatatypes -> asmgen.out("  jsr  prog8_lib.abs_b_stack")
-                in WordDatatypes -> asmgen.out("  jsr  prog8_lib.abs_w_stack")
-                DataType.FLOAT -> asmgen.out("  jsr  floats.abs_f_stack")
+                DataType.UBYTE -> asmgen.out("  ldy  #0")
+                DataType.BYTE -> asmgen.out("  jsr  prog8_lib.abs_b_stack")
+                DataType.UWORD -> {}
+                DataType.WORD -> asmgen.out("  jsr  prog8_lib.abs_w_stack")
                 else -> throw AssemblyError("weird type")
             }
         } else {
             when (dt) {
-                in ByteDatatypes -> {
-                    asmgen.out("  jsr  prog8_lib.abs_b_into_A")
-                    assignAsmGen.assignRegisterByte(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.A, false, scope, program, asmgen), CpuRegister.A)
-                }
-                in WordDatatypes -> {
-                    asmgen.out("  jsr  prog8_lib.abs_w_into_AY")
-                    assignAsmGen.assignRegisterpairWord(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.AY, false, scope, program, asmgen), RegisterOrPair.AY)
-                }
-                DataType.FLOAT -> {
-                    asmgen.out("  jsr  floats.abs_f_fac1")
-                    assignAsmGen.assignFAC1float(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.FAC1, true, scope, program, asmgen))
-                }
+                DataType.UBYTE -> asmgen.out("  ldy  #0")
+                DataType.BYTE -> asmgen.out("  jsr  prog8_lib.abs_b_into_AY")
+                DataType.UWORD -> {}
+                DataType.WORD -> asmgen.out("  jsr  prog8_lib.abs_w_into_AY")
                 else -> throw AssemblyError("weird type")
             }
+            assignAsmGen.assignRegisterpairWord(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.AY, false, scope, program, asmgen), RegisterOrPair.AY)
         }
     }
 
@@ -1350,7 +1172,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
 
     private fun funcPokeW(fcall: IFunctionCall) {
         when(val addrExpr = fcall.args[0]) {
-            is NumericLiteralValue -> {
+            is NumericLiteral -> {
                 asmgen.assignExpressionToRegister(fcall.args[1], RegisterOrPair.AY)
                 val addr = addrExpr.number.toHex()
                 asmgen.out("  sta  $addr |  sty  ${addr}+1")
@@ -1381,13 +1203,13 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                 }
             }
             is BinaryExpression -> {
-                if(addrExpr.operator=="+" && addrExpr.left is IdentifierReference && addrExpr.right is NumericLiteralValue) {
+                if(addrExpr.operator=="+" && addrExpr.left is IdentifierReference && addrExpr.right is NumericLiteral) {
                     val varname = asmgen.asmVariableName(addrExpr.left as IdentifierReference)
                     if(asmgen.isZpVar(addrExpr.left as IdentifierReference)) {
                         // pointervar is already in the zero page, no need to copy
                         asmgen.saveRegisterLocal(CpuRegister.X, (fcall as Node).definingSubroutine!!)
                         asmgen.assignExpressionToRegister(fcall.args[1], RegisterOrPair.AX)
-                        val index = (addrExpr.right as NumericLiteralValue).number.toHex()
+                        val index = (addrExpr.right as NumericLiteral).number.toHex()
                         asmgen.out("""
                             ldy  #$index
                             sta  ($varname),y
@@ -1409,7 +1231,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
 
     private fun funcPeekW(fcall: IFunctionCall, resultToStack: Boolean, resultRegister: RegisterOrPair?) {
         when(val addrExpr = fcall.args[0]) {
-            is NumericLiteralValue -> {
+            is NumericLiteral -> {
                 val addr = addrExpr.number.toHex()
                 asmgen.out("  lda  $addr |  ldy  ${addr}+1")
             }
@@ -1439,11 +1261,11 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                 }
             }
             is BinaryExpression -> {
-                if(addrExpr.operator=="+" && addrExpr.left is IdentifierReference && addrExpr.right is NumericLiteralValue) {
+                if(addrExpr.operator=="+" && addrExpr.left is IdentifierReference && addrExpr.right is NumericLiteral) {
                     val varname = asmgen.asmVariableName(addrExpr.left as IdentifierReference)
                     if(asmgen.isZpVar(addrExpr.left as IdentifierReference)) {
                         // pointervar is already in the zero page, no need to copy
-                        val index = (addrExpr.right as NumericLiteralValue).number.toHex()
+                        val index = (addrExpr.right as NumericLiteral).number.toHex()
                         asmgen.out("""
                             ldy  #$index
                             lda  ($varname),y
@@ -1490,14 +1312,14 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
             asmgen.out("  sta  P8ESTACK_LO,x |  tya |  sta  P8ESTACK_HI,x |  dex")
         } else {
             val reg = resultRegister ?: RegisterOrPair.AY
-            var needAsave = !(fcall.args[0] is DirectMemoryRead || fcall.args[0] is NumericLiteralValue || fcall.args[0] is IdentifierReference)
+            var needAsave = !(fcall.args[0] is DirectMemoryRead || fcall.args[0] is NumericLiteral || fcall.args[0] is IdentifierReference)
             if(!needAsave) {
                 val mr0 = fcall.args[0] as? DirectMemoryRead
                 val mr1 = fcall.args[1] as? DirectMemoryRead
                 if (mr0 != null)
-                    needAsave = mr0.addressExpression !is NumericLiteralValue && mr0.addressExpression !is IdentifierReference
+                    needAsave = mr0.addressExpression !is NumericLiteral && mr0.addressExpression !is IdentifierReference
                 if (mr1 != null)
-                    needAsave = needAsave or (mr1.addressExpression !is NumericLiteralValue && mr1.addressExpression !is IdentifierReference)
+                    needAsave = needAsave or (mr1.addressExpression !is NumericLiteral && mr1.addressExpression !is IdentifierReference)
             }
             when(reg) {
                 RegisterOrPair.AX -> {
@@ -1540,7 +1362,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
         val arg = fcall.args.single()
         if (!arg.inferType(program).isWords)
             throw AssemblyError("msb required word argument")
-        if (arg is NumericLiteralValue)
+        if (arg is NumericLiteral)
             throw AssemblyError("msb(const) should have been const-folded away")
         if (arg is IdentifierReference) {
             val sourceName = asmgen.asmVariableName(arg)
@@ -1551,6 +1373,16 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                     null, RegisterOrPair.A -> asmgen.out("  lda  $sourceName+1")
                     RegisterOrPair.X -> asmgen.out("  ldx  $sourceName+1")
                     RegisterOrPair.Y -> asmgen.out("  ldy  $sourceName+1")
+                    RegisterOrPair.AX -> asmgen.out("  lda  $sourceName+1 |  ldx  #0")
+                    RegisterOrPair.AY -> asmgen.out("  lda  $sourceName+1 |  ldy  #0")
+                    RegisterOrPair.XY -> asmgen.out("  ldx  $sourceName+1 |  ldy  #0")
+                    in Cx16VirtualRegisters -> {
+                        val regname = resultRegister.name.lowercase()
+                        if(asmgen.isTargetCpu(CpuType.CPU65c02))
+                            asmgen.out("  lda  $sourceName+1 |  sta  cx16.$regname |  stz  cx16.$regname+1")
+                        else
+                            asmgen.out("  lda  $sourceName+1 |  sta  cx16.$regname |  lda  #0 |  sta  cx16.$regname+1")
+                    }
                     else -> throw AssemblyError("invalid reg")
                 }
             }
@@ -1584,7 +1416,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
         val arg = fcall.args.single()
         if (!arg.inferType(program).isWords)
             throw AssemblyError("lsb required word argument")
-        if (arg is NumericLiteralValue)
+        if (arg is NumericLiteral)
             throw AssemblyError("lsb(const) should have been const-folded away")
 
         if (arg is IdentifierReference) {
@@ -1596,6 +1428,16 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                     null, RegisterOrPair.A -> asmgen.out("  lda  $sourceName")
                     RegisterOrPair.X -> asmgen.out("  ldx  $sourceName")
                     RegisterOrPair.Y -> asmgen.out("  ldy  $sourceName")
+                    RegisterOrPair.AX -> asmgen.out("  lda  $sourceName |  ldx  #0")
+                    RegisterOrPair.AY -> asmgen.out("  lda  $sourceName |  ldy  #0")
+                    RegisterOrPair.XY -> asmgen.out("  ldx  $sourceName |  ldy  #0")
+                    in Cx16VirtualRegisters -> {
+                        val regname = resultRegister.name.lowercase()
+                        if(asmgen.isTargetCpu(CpuType.CPU65c02))
+                            asmgen.out("  lda  $sourceName |  sta  cx16.$regname |  stz  cx16.$regname+1")
+                        else
+                            asmgen.out("  lda  $sourceName |  sta  cx16.$regname |  lda  #0 |  sta  cx16.$regname+1")
+                    }
                     else -> throw AssemblyError("invalid reg")
                 }
             }
@@ -1634,8 +1476,11 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
     private fun outputAddressAndLenghtOfArray(arg: Expression) {
         // address in P8ZP_SCRATCH_W1,  number of elements in A
         arg as IdentifierReference
+        val arrayVar = arg.targetVarDecl(program)!!
+        if(!arrayVar.isArray)
+            throw AssemblyError("length of non-array requested")
+        val size = arrayVar.arraysize!!.constIndex()!!
         val identifierName = asmgen.asmVariableName(arg)
-        val size = arg.targetVarDecl(program)!!.arraysize!!.constIndex()!!
         asmgen.out("""
                     lda  #<$identifierName
                     ldy  #>$identifierName
@@ -1646,7 +1491,9 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
     }
 
     private fun translateArguments(args: MutableList<Expression>, signature: FSignature, scope: Subroutine?) {
-        val callConv = signature.callConvention(args.map { it.inferType(program).getOr(DataType.UNDEFINED) })
+        val callConv = signature.callConvention(args.map {
+            it.inferType(program).getOrElse { throw AssemblyError("unknown dt") }
+        })
 
         fun getSourceForFloat(value: Expression): AsmAssignSource {
             return when (value) {
@@ -1654,14 +1501,14 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                     val addr = AddressOf(value, value.position)
                     AsmAssignSource.fromAstSource(addr, program, asmgen)
                 }
-                is NumericLiteralValue -> {
+                is NumericLiteral -> {
                     throw AssemblyError("float literals should have been converted into autovar")
                 }
                 else -> {
                     if(scope==null)
                         throw AssemblyError("cannot use float arguments outside of a subroutine scope")
 
-                    scope.asmGenInfo.usedFloatEvalResultVar2 = true
+                    asmgen.subroutineExtra(scope).usedFloatEvalResultVar2 = true
                     val variable = IdentifierReference(listOf(subroutineFloatEvalResultVar2), value.position)
                     val addr = AddressOf(variable, value.position)
                     addr.linkParents(value)

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

@@ -1,17 +1,13 @@
-package prog8.compiler.target.cpu6502.codegen
+package prog8.codegen.cpu6502
 
 import prog8.ast.Program
-import prog8.ast.base.*
 import prog8.ast.expressions.*
-import prog8.ast.statements.BuiltinFunctionStatementPlaceholder
-import prog8.ast.statements.Subroutine
-import prog8.ast.toHex
-import prog8.compiler.target.AssemblyError
-import prog8.compilerinterface.BuiltinFunctions
-import prog8.compilerinterface.CpuType
+import prog8.code.core.*
 import kotlin.math.absoluteValue
 
-internal class ExpressionsAsmGen(private val program: Program, private val asmgen: AsmGen) {
+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) {
@@ -34,108 +30,107 @@ internal class ExpressionsAsmGen(private val program: Program, private val asmge
             is TypecastExpression -> translateExpression(expression)
             is AddressOf -> translateExpression(expression)
             is DirectMemoryRead -> asmgen.translateDirectMemReadExpressionToRegAorStack(expression, true)
-            is NumericLiteralValue -> translateExpression(expression)
+            is NumericLiteral -> translateExpression(expression)
             is IdentifierReference -> translateExpression(expression)
-            is FunctionCall -> translateFunctionCallResultOntoStack(expression)
-            is ArrayLiteralValue, is StringLiteralValue -> throw AssemblyError("no asm gen for string/array literal value assignment - should have been replaced by a variable")
-            is RangeExpr -> throw AssemblyError("range expression should have been changed into array values")
+            is FunctionCallExpression -> translateFunctionCallResultOntoStack(expression)
+            is BuiltinFunctionCall -> asmgen.translateBuiltinFunctionCallExpression(expression, true, null)
+            is PipeExpression -> asmgen.translatePipeExpression(expression.source, expression.segments,
+                                                                expression, isStatement = false, pushResultOnEstack = true )
+            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: FunctionCall) {
+    private fun translateFunctionCallResultOntoStack(call: FunctionCallExpression) {
         // only for use in nested expression evaluation
 
-        val sub = call.target.targetStatement(program)
-        if(sub is BuiltinFunctionStatementPlaceholder) {
-            val builtinFunc = BuiltinFunctions.getValue(sub.name)
-            asmgen.translateBuiltinFunctionCallExpression(call, builtinFunc, true, null)
-        } else {
-            sub as Subroutine
-            asmgen.saveXbeforeCall(call)
-            asmgen.translateFunctionCall(call, true)
-            if(sub.regXasResult()) {
-                // store the return value in X somewhere that we can acces again below
-                asmgen.out("  stx  P8ZP_SCRATCH_REG")
-            }
-            asmgen.restoreXafterCall(call)
+        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
+        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.${reg.registerOrPair.toString().lowercase()}
                             sta  P8ESTACK_LO,x
-                            dex""")
+                            lda  cx16.${reg.registerOrPair.toString().lowercase()}+1
+                            sta  P8ESTACK_HI,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 -> {}
                 }
+            } 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 -> {}
             }
         }
     }
@@ -209,7 +204,7 @@ internal class ExpressionsAsmGen(private val program: Program, private val asmge
         asmgen.out("  lda  #<$name |  sta  P8ESTACK_LO,x |  lda  #>$name  |  sta  P8ESTACK_HI,x  | dex")
     }
 
-    private fun translateExpression(expr: NumericLiteralValue) {
+    private fun translateExpression(expr: NumericLiteral) {
         when(expr.type) {
             DataType.UBYTE, DataType.BYTE -> asmgen.out(" lda  #${expr.number.toHex()}  | sta  P8ESTACK_LO,x  | dex")
             DataType.UWORD, DataType.WORD -> asmgen.out("""
@@ -220,7 +215,7 @@ internal class ExpressionsAsmGen(private val program: Program, private val asmge
                 dex
             """)
             DataType.FLOAT -> {
-                val floatConst = asmgen.getFloatAsmConst(expr.number)
+                val floatConst = allocator.getFloatAsmConst(expr.number)
                 asmgen.out(" lda  #<$floatConst |  ldy  #>$floatConst |  jsr  floats.push_float")
             }
             else -> throw AssemblyError("weird type")
@@ -254,8 +249,8 @@ internal class ExpressionsAsmGen(private val program: Program, private val asmge
         if(!leftIDt.isKnown || !rightIDt.isKnown)
             throw AssemblyError("can't infer type of both expression operands")
 
-        val leftDt = leftIDt.getOr(DataType.UNDEFINED)
-        val rightDt = rightIDt.getOr(DataType.UNDEFINED)
+        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) {
             "+" -> {
@@ -420,7 +415,7 @@ internal class ExpressionsAsmGen(private val program: Program, private val asmge
                                 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") }
+                                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")
                         }
@@ -537,13 +532,20 @@ internal class ExpressionsAsmGen(private val program: Program, private val asmge
                     }
                 }
             }
+            in ComparisonOperators -> {
+                if(leftDt in NumericDatatypes && rightDt in NumericDatatypes) {
+                    val rightVal = expr.right.constValue(program)?.number?.toInt()
+                    if(rightVal==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) {
+        if(leftDt==DataType.STR && rightDt==DataType.STR && expr.operator in ComparisonOperators) {
             translateCompareStrings(expr.left, expr.operator, expr.right)
         }
         else {
@@ -559,6 +561,69 @@ internal class ExpressionsAsmGen(private val program: Program, private val asmge
         }
     }
 
+    private fun translateComparisonWithZero(expr: Expression, dt: DataType, operator: String) {
+        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) {
@@ -578,9 +643,7 @@ internal class ExpressionsAsmGen(private val program: Program, private val asmge
     private fun translateExpression(expr: PrefixExpression) {
         translateExpressionInternal(expr.expression)
         val itype = expr.inferType(program)
-        if(!itype.isKnown)
-            throw AssemblyError("unknown dt")
-        val type = itype.getOr(DataType.UNDEFINED)
+        val type = itype.getOrElse { throw AssemblyError("unknown dt") }
         when(expr.operator) {
             "+" -> {}
             "-" -> {
@@ -605,6 +668,15 @@ internal class ExpressionsAsmGen(private val program: Program, private val asmge
             }
             "not" -> {
                 when(type) {
+                    // if reg==0 ->
+                    /*
+        lda  P8ESTACK_LO+1,x
+		beq  +
+		lda  #1
++		eor  #1
+		sta  P8ESTACK_LO+1,x
+		rts
+                     */
                     in ByteDatatypes -> asmgen.out("  jsr  prog8_lib.not_byte")
                     in WordDatatypes -> asmgen.out("  jsr  prog8_lib.not_word")
                     else -> throw AssemblyError("weird type")
@@ -631,7 +703,7 @@ internal class ExpressionsAsmGen(private val program: Program, private val asmge
                     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")
+                    asmgen.out("  lda  #<($arrayVarName+$indexValue) |  ldy  #>($arrayVarName+$indexValue) |  jsr  floats.push_float")
                 }
                 else -> throw AssemblyError("weird element type")
             }
@@ -663,7 +735,6 @@ internal class ExpressionsAsmGen(private val program: Program, private val asmge
 
     private fun translateBinaryOperatorBytes(operator: String, types: DataType) {
         when(operator) {
-            "**" -> throw AssemblyError("** operator requires floats")
             "*" -> asmgen.out("  jsr  prog8_lib.mul_byte")  //  the optimized routines should have been checked earlier
             "/" -> asmgen.out(if(types==DataType.UBYTE) "  jsr  prog8_lib.idiv_ub" else "  jsr  prog8_lib.idiv_b")
             "%" -> {
@@ -705,7 +776,6 @@ internal class ExpressionsAsmGen(private val program: Program, private val asmge
 
     private fun translateBinaryOperatorWords(operator: String, dt: DataType) {
         when(operator) {
-            "**" -> throw AssemblyError("** operator requires floats")
             "*" -> asmgen.out("  jsr  prog8_lib.mul_word")
             "/" -> asmgen.out(if(dt==DataType.UWORD) "  jsr  prog8_lib.idiv_uw" else "  jsr  prog8_lib.idiv_w")
             "%" -> {
@@ -727,7 +797,8 @@ internal class ExpressionsAsmGen(private val program: Program, private val asmge
             "<=" -> 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.notequal_w")
+            "&" -> asmgen.out("  jsr  prog8_lib.bitand_w")
             "^" -> asmgen.out("  jsr  prog8_lib.bitxor_w")
             "|" -> asmgen.out("  jsr  prog8_lib.bitor_w")
             "and" -> asmgen.out("  jsr  prog8_lib.and_w")
@@ -739,7 +810,6 @@ internal class ExpressionsAsmGen(private val program: Program, private val asmge
 
     private fun translateBinaryOperatorFloats(operator: String) {
         when(operator) {
-            "**" -> asmgen.out(" jsr  floats.pow_f")
             "*" -> asmgen.out("  jsr  floats.mul_f")
             "/" -> asmgen.out("  jsr  floats.div_f")
             "+" -> asmgen.out("  jsr  floats.add_f")

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

@@ -1,40 +1,36 @@
-package prog8.compiler.target.cpu6502.codegen
+package prog8.codegen.cpu6502
 
+import com.github.michaelbull.result.fold
 import prog8.ast.Program
-import prog8.ast.base.ArrayToElementTypes
-import prog8.ast.base.DataType
-import prog8.ast.base.RegisterOrPair
 import prog8.ast.expressions.IdentifierReference
-import prog8.ast.expressions.RangeExpr
+import prog8.ast.expressions.RangeExpression
 import prog8.ast.statements.ForLoop
-import prog8.ast.toHex
-import prog8.compiler.target.AssemblyError
-import prog8.compilerinterface.toConstantIntegerRange
+import prog8.code.core.*
 import kotlin.math.absoluteValue
 
-internal class ForLoopsAsmGen(private val program: Program, private val asmgen: AsmGen) {
+internal class ForLoopsAsmGen(private val program: Program, private val asmgen: AsmGen, private val zeropage: Zeropage) {
 
     internal fun translate(stmt: ForLoop) {
         val iterableDt = stmt.iterable.inferType(program)
         if(!iterableDt.isKnown)
             throw AssemblyError("unknown dt")
         when(stmt.iterable) {
-            is RangeExpr -> {
-                val range = (stmt.iterable as RangeExpr).toConstantIntegerRange()
+            is RangeExpression -> {
+                val range = (stmt.iterable as RangeExpression).toConstantIntegerRange()
                 if(range==null) {
-                    translateForOverNonconstRange(stmt, iterableDt.getOr(DataType.UNDEFINED), stmt.iterable as RangeExpr)
+                    translateForOverNonconstRange(stmt, iterableDt.getOrElse { throw AssemblyError("unknown dt") }, stmt.iterable as RangeExpression)
                 } else {
-                    translateForOverConstRange(stmt, iterableDt.getOr(DataType.UNDEFINED), range)
+                    translateForOverConstRange(stmt, iterableDt.getOrElse { throw AssemblyError("unknown dt") }, range)
                 }
             }
             is IdentifierReference -> {
-                translateForOverIterableVar(stmt, iterableDt.getOr(DataType.UNDEFINED), stmt.iterable as IdentifierReference)
+                translateForOverIterableVar(stmt, iterableDt.getOrElse { throw AssemblyError("unknown dt") }, stmt.iterable as IdentifierReference)
             }
             else -> throw AssemblyError("can't iterate over ${stmt.iterable.javaClass} - should have been replaced by a variable")
         }
     }
 
-    private fun translateForOverNonconstRange(stmt: ForLoop, iterableDt: DataType, range: RangeExpr) {
+    private fun translateForOverNonconstRange(stmt: ForLoop, iterableDt: DataType, range: RangeExpression) {
         val loopLabel = asmgen.makeLabel("for_loop")
         val endLabel = asmgen.makeLabel("for_end")
         val modifiedLabel = asmgen.makeLabel("for_modified")
@@ -289,13 +285,15 @@ $loopLabel          sty  $indexVar
                         bne  $loopLabel
                         beq  $endLabel""")
                 }
-                if(length>=16 && asmgen.zeropage.hasByteAvailable()) {
-                    // allocate index var on ZP
-                    val zpAddr = asmgen.zeropage.allocate(indexVar, DataType.UBYTE, stmt.position, asmgen.errors)
-                    asmgen.out("""$indexVar = $zpAddr  ; auto zp UBYTE""")
+                if(length>=16) {
+                    // allocate index var on ZP if possible
+                    val result = zeropage.allocate(listOf(indexVar), DataType.UBYTE, null, stmt.position, asmgen.errors)
+                    result.fold(
+                        success = { (address,_)-> asmgen.out("""$indexVar = $address  ; auto zp UBYTE""") },
+                        failure = { asmgen.out("$indexVar    .byte  0") }
+                    )
                 } else {
-                    asmgen.out("""
-$indexVar           .byte  0""")
+                    asmgen.out("$indexVar    .byte  0")
                 }
                 asmgen.out(endLabel)
             }
@@ -328,13 +326,15 @@ $loopLabel          sty  $indexVar
                         bne  $loopLabel
                         beq  $endLabel""")
                 }
-                if(length>=16 && asmgen.zeropage.hasByteAvailable()) {
-                    // allocate index var on ZP
-                    val zpAddr = asmgen.zeropage.allocate(indexVar, DataType.UBYTE, stmt.position, asmgen.errors)
-                    asmgen.out("""$indexVar = $zpAddr  ; auto zp UBYTE""")
+                if(length>=16) {
+                    // allocate index var on ZP if possible
+                    val result = zeropage.allocate(listOf(indexVar), DataType.UBYTE, null, stmt.position, asmgen.errors)
+                    result.fold(
+                        success = { (address,_)-> asmgen.out("""$indexVar = $address  ; auto zp UBYTE""") },
+                        failure = { asmgen.out("$indexVar    .byte  0") }
+                    )
                 } else {
-                    asmgen.out("""
-$indexVar           .byte  0""")
+                    asmgen.out("$indexVar    .byte  0")
                 }
                 asmgen.out(endLabel)
             }
@@ -588,6 +588,10 @@ $loopLabel""")
         asmgen.loopEndLabels.pop()
     }
 
-    private fun assignLoopvar(stmt: ForLoop, range: RangeExpr) =
-        asmgen.assignExpressionToVariable(range.from, asmgen.asmVariableName(stmt.loopVar), stmt.loopVarDt(program).getOr(DataType.UNDEFINED), stmt.definingSubroutine)
+    private fun assignLoopvar(stmt: ForLoop, range: RangeExpression) =
+        asmgen.assignExpressionToVariable(
+            range.from,
+            asmgen.asmVariableName(stmt.loopVar),
+            stmt.loopVarDt(program).getOrElse { throw AssemblyError("unknown dt") },
+            stmt.definingSubroutine)
 }

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

@@ -1,22 +1,23 @@
-package prog8.compiler.target.cpu6502.codegen
+package prog8.codegen.cpu6502
 
 import prog8.ast.IFunctionCall
 import prog8.ast.Node
 import prog8.ast.Program
-import prog8.ast.base.*
-import prog8.ast.expressions.*
+import prog8.ast.expressions.AddressOf
+import prog8.ast.expressions.Expression
+import prog8.ast.expressions.IdentifierReference
+import prog8.ast.expressions.NumericLiteral
 import prog8.ast.statements.*
-import prog8.compiler.target.AssemblyError
-import prog8.compiler.target.cpu6502.codegen.assignment.AsmAssignSource
-import prog8.compiler.target.cpu6502.codegen.assignment.AsmAssignTarget
-import prog8.compiler.target.cpu6502.codegen.assignment.AsmAssignment
-import prog8.compiler.target.cpu6502.codegen.assignment.TargetStorageKind
-import prog8.compilerinterface.CpuType
+import prog8.code.core.*
+import prog8.codegen.cpu6502.assignment.AsmAssignSource
+import prog8.codegen.cpu6502.assignment.AsmAssignTarget
+import prog8.codegen.cpu6502.assignment.AsmAssignment
+import prog8.codegen.cpu6502.assignment.TargetStorageKind
 
 
 internal class FunctionCallAsmGen(private val program: Program, private val asmgen: AsmGen) {
 
-    internal fun translateFunctionCallStatement(stmt: IFunctionCall) {
+    internal fun translateFunctionCallStatement(stmt: FunctionCallStatement) {
         saveXbeforeCall(stmt)
         translateFunctionCall(stmt, false)
         restoreXafterCall(stmt)
@@ -35,7 +36,7 @@ internal class FunctionCallAsmGen(private val program: Program, private val asmg
     }
 
     internal fun saveXbeforeCall(gosub: GoSub) {
-        val sub = gosub.identifier?.targetSubroutine(program)
+        val sub = gosub.identifier.targetSubroutine(program)
         if(sub?.shouldSaveX()==true) {
             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)
@@ -57,7 +58,7 @@ internal class FunctionCallAsmGen(private val program: Program, private val asmg
     }
 
     internal fun restoreXafterCall(gosub: GoSub) {
-        val sub = gosub.identifier?.targetSubroutine(program)
+        val sub = gosub.identifier.targetSubroutine(program)
         if(sub?.shouldSaveX()==true) {
             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)
@@ -67,6 +68,10 @@ internal class FunctionCallAsmGen(private val program: Program, private val asmg
         }
     }
 
+    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) {
         // 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!
@@ -76,8 +81,10 @@ internal class FunctionCallAsmGen(private val program: Program, private val asmg
         val sub = call.target.targetSubroutine(program) ?: throw AssemblyError("undefined subroutine ${call.target}")
         val subAsmName = asmgen.asmSymbolName(call.target)
 
-        if(!isExpression && !sub.isAsmSubroutine)
-            throw AssemblyError("functioncall statements to non-asmsub should have been replaced by GoSub $call")
+        if(!isExpression && !sub.isAsmSubroutine) {
+            if(!optimizeIntArgsViaRegisters(sub))
+                throw AssemblyError("functioncall statements to non-asmsub should have been replaced by GoSub $call")
+        }
 
         if(sub.isAsmSubroutine) {
             argumentsViaRegisters(sub, call)
@@ -87,8 +94,7 @@ internal class FunctionCallAsmGen(private val program: Program, private val asmg
                 // 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}")
-                val assembly = sub.statements.single() as InlineAssembly
-                asmgen.translate(assembly)
+                sub.statements.forEach { asmgen.translate(it as InlineAssembly) }
                 asmgen.out("  \t; inlined routine end: ${sub.name}")
             } else {
                 asmgen.out("  jsr  $subAsmName")
@@ -98,26 +104,38 @@ internal class FunctionCallAsmGen(private val program: Program, private val asmg
             if(sub.inline)
                 throw AssemblyError("can only reliably inline asmsub routines at this time")
 
-            argumentsViaVariables(sub, call)
+            if(optimizeIntArgsViaRegisters(sub)) {
+                if(sub.parameters.size==1) {
+                    val register = if (sub.parameters[0].type in ByteDatatypes) RegisterOrPair.A else RegisterOrPair.AY
+                    argumentViaRegister(sub, IndexedValue(0, sub.parameters[0]), call.args[0], register)
+                } else {
+                    // 2 byte params, second in Y, first in A
+                    argumentViaRegister(sub, IndexedValue(0, sub.parameters[0]), call.args[0], RegisterOrPair.A)
+                    if(!call.args[1].isSimple)
+                        asmgen.out("  pha")
+                    argumentViaRegister(sub, IndexedValue(1, sub.parameters[1]), call.args[1], RegisterOrPair.Y)
+                    if(!call.args[1].isSimple)
+                        asmgen.out("  pla")
+                }
+            } else {
+                // arguments via variables
+                for(arg in sub.parameters.withIndex().zip(call.args))
+                    argumentViaVariable(sub, arg.first.value, arg.second)
+            }
             asmgen.out("  jsr  $subAsmName")
         }
 
         // remember: dealing with the X register and/or dealing with return values is the responsibility of the caller
     }
 
-    private fun argumentsViaVariables(sub: Subroutine, call: IFunctionCall) {
-        for(arg in sub.parameters.withIndex().zip(call.args))
-            argumentViaVariable(sub, arg.first, arg.second)
-    }
-
     private fun argumentsViaRegisters(sub: Subroutine, call: IFunctionCall) {
         if(sub.parameters.size==1) {
             argumentViaRegister(sub, IndexedValue(0, sub.parameters.single()), call.args[0])
         } else {
-            if(asmgen.asmsubArgsHaveRegisterClobberRisk(call.args, sub.asmParameterRegisters)) {
-                registerArgsViaStackEvaluation(call, sub)
+            if(asmsub6502ArgsHaveRegisterClobberRisk(call.args, sub.asmParameterRegisters)) {
+                registerArgsViaCpuStackEvaluation(call, sub)
             } else {
-                asmgen.asmsubArgsEvalOrder(sub).forEach {
+                asmsub6502ArgsEvalOrder(sub).forEach {
                     val param = sub.parameters[it]
                     val arg = call.args[it]
                     argumentViaRegister(sub, IndexedValue(it, param), arg)
@@ -126,154 +144,45 @@ internal class FunctionCallAsmGen(private val program: Program, private val asmg
         }
     }
 
-    private fun registerArgsViaStackEvaluation(stmt: IFunctionCall, sub: Subroutine) {
+    private fun registerArgsViaCpuStackEvaluation(call: IFunctionCall, callee: Subroutine) {
         // this is called when one or more of the arguments are 'complex' and
         // cannot be assigned to a register easily or risk clobbering other registers.
-        // TODO find another way to prepare the arguments, without using the eval stack
 
-        if(sub.parameters.isEmpty())
+        require(callee.isAsmSubroutine)
+        if(callee.parameters.isEmpty())
             return
 
-
-        // 1. load all arguments reversed onto the stack: first arg goes last (is on top).
-
-        for (arg in stmt.args.reversed())
-            asmgen.translateExpression(arg)
-
-        // TODO here's an alternative to the above, but for now generates bigger code due to intermediate register steps:
-//        for (arg in stmt.args.reversed()) {
-//            // note this stuff below is needed to (eventually) avoid calling asmgen.translateExpression()
-//            // TODO also This STILL requires the translateNormalAssignment() to be fixed to avoid stack eval for expressions...
-//            val dt = arg.inferType(program).getOr(DataType.UNDEFINED)
-//            asmgen.assignExpressionTo(arg, AsmAssignTarget(TargetStorageKind.STACK, program, asmgen, dt, sub))
-//        }
-
-        var argForCarry: IndexedValue<Pair<Expression, RegisterOrStatusflag>>? = null
-        var argForXregister: IndexedValue<Pair<Expression, RegisterOrStatusflag>>? = null
-        var argForAregister: IndexedValue<Pair<Expression, RegisterOrStatusflag>>? = null
-
-        asmgen.out("  inx")     // align estack pointer
-
-        for(argi in stmt.args.zip(sub.asmParameterRegisters).withIndex()) {
-            val plusIdxStr = if(argi.index==0) "" else "+${argi.index}"
-            when {
-                argi.value.second.statusflag == Statusflag.Pc -> {
-                    require(argForCarry == null)
-                    argForCarry = argi
-                }
-                argi.value.second.statusflag != null -> throw AssemblyError("can only use Carry as status flag parameter")
-                argi.value.second.registerOrPair in arrayOf(RegisterOrPair.X, RegisterOrPair.AX, RegisterOrPair.XY) -> {
-                    require(argForXregister==null)
-                    argForXregister = argi
-                }
-                argi.value.second.registerOrPair in arrayOf(RegisterOrPair.A, RegisterOrPair.AY) -> {
-                    require(argForAregister == null)
-                    argForAregister = argi
-                }
-                argi.value.second.registerOrPair == RegisterOrPair.Y -> {
-                    asmgen.out("  ldy  P8ESTACK_LO$plusIdxStr,x")
-                }
-                argi.value.second.registerOrPair in Cx16VirtualRegisters -> {
-                    // immediately output code to load the virtual register, to avoid clobbering the A register later
-                    when (sub.parameters[argi.index].type) {
-                        in ByteDatatypes -> {
-                            // only load the lsb of the virtual register
-                            asmgen.out(
-                                """
-                                lda  P8ESTACK_LO$plusIdxStr,x
-                                sta  cx16.${argi.value.second.registerOrPair.toString().lowercase()}
-                            """)
-                            if (asmgen.isTargetCpu(CpuType.CPU65c02))
-                                asmgen.out(
-                                    "  stz  cx16.${
-                                        argi.value.second.registerOrPair.toString().lowercase()
-                                    }+1")
-                            else
-                                asmgen.out(
-                                    "  lda  #0 |  sta  cx16.${
-                                        argi.value.second.registerOrPair.toString().lowercase()
-                                    }+1")
-                        }
-                        in WordDatatypes, in IterableDatatypes ->
-                            asmgen.out(
-                                """
-                                lda  P8ESTACK_LO$plusIdxStr,x
-                                sta  cx16.${argi.value.second.registerOrPair.toString().lowercase()}
-                                lda  P8ESTACK_HI$plusIdxStr,x
-                                sta  cx16.${
-                                    argi.value.second.registerOrPair.toString().lowercase()
-                                }+1
-                            """)
-                        else -> throw AssemblyError("weird dt")
-                    }
-                }
-                else -> throw AssemblyError("weird argument")
-            }
+        // 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])
         }
-
-        if(argForCarry!=null) {
-            val plusIdxStr = if(argForCarry.index==0) "" else "+${argForCarry.index}"
-            asmgen.out("""
-                clc
-                lda  P8ESTACK_LO$plusIdxStr,x
-                beq  +
-                sec
-+               php""")             // push the status flags
+        argOrder.forEach {
+            val param = callee.parameters[it]
+            val targetVar = callee.searchAsmParameter(param.name)!!
+            asmgen.popCpuStack(param.type, targetVar, (call as Node).definingSubroutine)
         }
-
-        if(argForAregister!=null) {
-            val plusIdxStr = if(argForAregister.index==0) "" else "+${argForAregister.index}"
-            when(argForAregister.value.second.registerOrPair) {
-                RegisterOrPair.A -> asmgen.out("  lda  P8ESTACK_LO$plusIdxStr,x")
-                RegisterOrPair.AY -> asmgen.out("  lda  P8ESTACK_LO$plusIdxStr,x |  ldy  P8ESTACK_HI$plusIdxStr,x")
-                else -> throw AssemblyError("weird arg")
-            }
-        }
-
-        if(argForXregister!=null) {
-            val plusIdxStr = if(argForXregister.index==0) "" else "+${argForXregister.index}"
-
-            if(argForAregister!=null)
-                asmgen.out("  pha")
-            when(argForXregister.value.second.registerOrPair) {
-                RegisterOrPair.X -> asmgen.out("  lda  P8ESTACK_LO$plusIdxStr,x |  tax")
-                RegisterOrPair.AX -> asmgen.out("  ldy  P8ESTACK_LO$plusIdxStr,x |  lda  P8ESTACK_HI$plusIdxStr,x |  tax |  tya")
-                RegisterOrPair.XY -> asmgen.out("  ldy  P8ESTACK_HI$plusIdxStr,x |  lda  P8ESTACK_LO$plusIdxStr,x |  tax")
-                else -> throw AssemblyError("weird arg")
-            }
-            if(argForAregister!=null)
-                asmgen.out("  pla")
-        } else {
-            repeat(sub.parameters.size - 1) { asmgen.out("  inx") }       // unwind stack
-        }
-
-        if(argForCarry!=null)
-            asmgen.out("  plp")       // set the carry flag back to correct value
     }
 
-    private fun argumentViaVariable(sub: Subroutine, parameter: IndexedValue<SubroutineParameter>, value: Expression) {
+    private fun argumentViaVariable(sub: Subroutine, parameter: SubroutineParameter, value: Expression) {
         // pass parameter via a regular variable (not via registers)
         val valueIDt = value.inferType(program)
-        if(!valueIDt.isKnown)
-            throw AssemblyError("unknown dt")
-        val valueDt = valueIDt.getOr(DataType.UNDEFINED)
-        if(!isArgumentTypeCompatible(valueDt, parameter.value.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.value.name)
-        asmgen.assignExpressionToVariable(value, varName, parameter.value.type, sub)
+        val varName = asmgen.asmVariableName(sub.scopedName + parameter.name)
+        asmgen.assignExpressionToVariable(value, varName, parameter.type, sub)
     }
 
-    private fun argumentViaRegister(sub: Subroutine, parameter: IndexedValue<SubroutineParameter>, value: Expression) {
+    private fun argumentViaRegister(sub: Subroutine, parameter: IndexedValue<SubroutineParameter>, value: Expression, registerOverride: RegisterOrPair? = null) {
         // pass argument via a register parameter
         val valueIDt = value.inferType(program)
-        if(!valueIDt.isKnown)
-            throw AssemblyError("unknown dt")
-        val valueDt = valueIDt.getOr(DataType.UNDEFINED)
+        val valueDt = valueIDt.getOrElse { throw AssemblyError("unknown dt") }
         if(!isArgumentTypeCompatible(valueDt, parameter.value.type))
             throw AssemblyError("argument type incompatible")
 
-        val paramRegister = sub.asmParameterRegisters[parameter.index]
+        val paramRegister = if(registerOverride==null) sub.asmParameterRegisters[parameter.index] else RegisterOrStatusflag(registerOverride, null)
         val statusflag = paramRegister.statusflag
         val register = paramRegister.registerOrPair
         val requiredDt = parameter.value.type
@@ -288,29 +197,28 @@ internal class FunctionCallAsmGen(private val program: Program, private val asmg
                 // this param needs to be set last, right before the jsr
                 // for now, this is already enforced on the subroutine definition by the Ast Checker
                 when(value) {
-                    is NumericLiteralValue -> {
+                    is NumericLiteral -> {
                         val carrySet = value.number.toInt() != 0
                         asmgen.out(if(carrySet) "  sec" else "  clc")
                     }
                     is IdentifierReference -> {
                         val sourceName = asmgen.asmVariableName(value)
                         asmgen.out("""
-                pha
-                clc
-                lda  $sourceName
-                beq  +
-                sec  
-    +           pla
-    """)
+                            pha
+                            clc
+                            lda  $sourceName
+                            beq  +
+                            sec  
++                           pla""")
                     }
                     else -> {
                         asmgen.assignExpressionToRegister(value, RegisterOrPair.A)
                         asmgen.out("""
-                                    beq  +
-                                    sec
-                                    bcs  ++
-    +                               clc
-    +""")
+                            beq  +
+                            sec
+                            bcs  ++
++                           clc
++""")
                     }
                 }
             } else throw AssemblyError("can only use Carry as status flag parameter")

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

@@ -1,12 +1,10 @@
-package prog8.compiler.target.cpu6502.codegen
+package prog8.codegen.cpu6502
 
 import prog8.ast.Program
-import prog8.ast.base.*
 import prog8.ast.expressions.IdentifierReference
-import prog8.ast.expressions.NumericLiteralValue
+import prog8.ast.expressions.NumericLiteral
 import prog8.ast.statements.PostIncrDecr
-import prog8.ast.toHex
-import prog8.compiler.target.AssemblyError
+import prog8.code.core.*
 
 
 internal class PostIncrDecrAsmGen(private val program: Program, private val asmgen: AsmGen) {
@@ -41,7 +39,7 @@ internal class PostIncrDecrAsmGen(private val program: Program, private val asmg
             }
             targetMemory!=null -> {
                 when (val addressExpr = targetMemory.addressExpression) {
-                    is NumericLiteralValue -> {
+                    is NumericLiteral -> {
                         val what = addressExpr.number.toHex()
                         asmgen.out(if(incr) "  inc  $what" else "  dec  $what")
                     }
@@ -83,7 +81,7 @@ internal class PostIncrDecrAsmGen(private val program: Program, private val asmg
 """)
                         }
                         DataType.FLOAT -> {
-                            asmgen.out("  lda  #<$asmArrayvarname+$indexValue |  ldy  #>$asmArrayvarname+$indexValue")
+                            asmgen.out("  lda  #<($asmArrayvarname+$indexValue) |  ldy  #>($asmArrayvarname+$indexValue)")
                             asmgen.out(if(incr) "  jsr  floats.inc_var_f" else "  jsr  floats.dec_var_f")
                         }
                         else -> throw AssemblyError("need numeric type")

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

@@ -0,0 +1,656 @@
+package prog8.codegen.cpu6502
+
+import prog8.ast.Program
+import prog8.ast.statements.*
+import prog8.code.*
+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
+
+/**
+ * Generates the main parts of the program:
+ *  - entry/exit code
+ *  - initialization routines
+ *  - blocks
+ *  - subroutines
+ *  - all variables (note: VarDecl ast nodes are *NOT* used anymore for this! now uses IVariablesAndConsts data tables!)
+ */
+internal class ProgramAndVarsGen(
+    val program: Program,
+    val options: CompilationOptions,
+    val errors: IErrorReporter,
+    private val symboltable: SymbolTable,
+    private val functioncallAsmGen: FunctionCallAsmGen,
+    private val asmgen: AsmGen,
+    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.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
+        if(allBlocks.first().name != "main")
+            throw AssemblyError("first block should be 'main'")
+
+        if(errors.noErrors())  {
+            program.allBlocks.forEach { block2asm(it) }
+            memorySlabs()
+            footer()
+        }
+    }
+
+    private fun header() {
+        val ourName = this.javaClass.name
+        val cpu = when(compTarget.machine.cpu) {
+            CpuType.CPU6502 -> "6502"
+            CpuType.CPU65c02 -> "w65c02"
+            else -> "unsupported"
+        }
+
+        asmgen.out("; $cpu assembly code for '${program.name}'")
+        asmgen.out("; generated by $ourName on ${LocalDateTime.now().withNano(0)}")
+        asmgen.out("; assembler syntax is for the 64tasm cross-assembler")
+        asmgen.out("; output options: output=${options.output} launcher=${options.launcher} zp=${options.zeropage}")
+        asmgen.out("")
+        asmgen.out(".cpu  '$cpu'\n.enc  'none'\n")
+
+        // the global prog8 variables needed
+        val zp = zeropage
+        asmgen.out("P8ZP_SCRATCH_B1 = ${zp.SCRATCH_B1}")
+        asmgen.out("P8ZP_SCRATCH_REG = ${zp.SCRATCH_REG}")
+        asmgen.out("P8ZP_SCRATCH_W1 = ${zp.SCRATCH_W1}    ; word")
+        asmgen.out("P8ZP_SCRATCH_W2 = ${zp.SCRATCH_W2}    ; word")
+        asmgen.out("P8ESTACK_LO = ${compTarget.machine.ESTACK_LO.toHex()}")
+        asmgen.out("P8ESTACK_HI = ${compTarget.machine.ESTACK_HI.toHex()}")
+
+        when(options.output) {
+            OutputType.RAW -> {
+                asmgen.out("; ---- raw assembler program ----")
+                asmgen.out("* = ${options.loadAddress.toHex()}\n")
+            }
+            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)
+                        }
+                        asmgen.out("; ---- basic program with sys call ----")
+                        asmgen.out("* = ${options.loadAddress.toHex()}")
+                        val year = LocalDate.now().year
+                        asmgen.out("  .word  (+), $year")
+                        asmgen.out("  .null  $9e, format(' %d ', prog8_entrypoint), $3a, $8f, ' prog8'")
+                        asmgen.out("+\t.word  0")
+                        asmgen.out("prog8_entrypoint\t; assembly code starts here\n")
+                        if(!options.noSysInit)
+                            asmgen.out("  jsr  ${compTarget.name}.init_system")
+                        asmgen.out("  jsr  ${compTarget.name}.init_system_phase2")
+                    }
+                    CbmPrgLauncherType.NONE -> {
+                        asmgen.out("; ---- program without basic sys call ----")
+                        asmgen.out("* = ${options.loadAddress.toHex()}\n")
+                        if(!options.noSysInit)
+                            asmgen.out("  jsr  ${compTarget.name}.init_system")
+                        asmgen.out("  jsr  ${compTarget.name}.init_system_phase2")
+                    }
+                }
+            }
+            OutputType.XEX -> {
+                asmgen.out("; ---- atari xex program ----")
+                asmgen.out("* = ${options.loadAddress.toHex()}\n")
+                if(!options.noSysInit)
+                    asmgen.out("  jsr  ${compTarget.name}.init_system")
+                asmgen.out("  jsr  ${compTarget.name}.init_system_phase2")
+            }
+        }
+
+        if(options.zeropage !in arrayOf(ZeropageType.BASICSAFE, ZeropageType.DONTUSE)) {
+            asmgen.out("""
+                ; zeropage is clobbered so we need to reset the machine at exit
+                lda  #>sys.reset_system
+                pha
+                lda  #<sys.reset_system
+                pha""")
+        }
+
+        // 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 |  lda  #4 |  sta  $01")
+                if(!options.noSysInit)
+                    asmgen.out("  jmp  ${compTarget.name}.cleanup_at_exit")
+                else
+                    asmgen.out("  rts")
+            }
+            "c64" -> {
+                asmgen.out("  jsr  main.start |  lda  #31 |  sta  $01")
+                if(!options.noSysInit)
+                    asmgen.out("  jmp  ${compTarget.name}.cleanup_at_exit")
+                else
+                    asmgen.out("  rts")
+            }
+            "c128" -> {
+                asmgen.out("  jsr  main.start")
+                // TODO c128: how to bank basic+kernal back in?
+                if(!options.noSysInit)
+                    asmgen.out("  jmp  ${compTarget.name}.cleanup_at_exit")
+                else
+                    asmgen.out("  rts")
+            }
+            else -> asmgen.jmp("main.start")
+        }
+    }
+
+    private fun memorySlabs() {
+        asmgen.out("; memory slabs")
+        asmgen.out("prog8_slabs\t.block")
+        for((name, info) in allocator.memorySlabs) {
+            if(info.second>1u)
+                asmgen.out("\t.align  ${info.second.toHex()}")
+            asmgen.out("$name\t.fill  ${info.first}")
+        }
+        asmgen.out("\t.bend")
+    }
+
+    private fun footer() {
+        // the global list of all floating point constants for the whole program
+        asmgen.out("; global float constants")
+        for (flt in allocator.globalFloatConsts) {
+            val floatFill = compTarget.machine.getFloat(flt.key).makeFloatFillAsm()
+            val floatvalue = flt.key
+            asmgen.out("${flt.value}\t.byte  $floatFill  ; float $floatvalue")
+        }
+
+        // program end
+        asmgen.out("prog8_program_end\t; end of program label for progend()")
+    }
+
+    private fun block2asm(block: Block) {
+        asmgen.out("")
+        asmgen.out("; ---- block: '${block.name}' ----")
+        if(block.address!=null)
+            asmgen.out("* = ${block.address!!.toHex()}")
+        else {
+            if("align_word" in block.options())
+                asmgen.out("\t.align 2")
+            else if("align_page" in block.options())
+                asmgen.out("\t.align $100")
+        }
+
+        asmgen.out("${block.name}\t" + (if("force_output" in block.options()) ".block\n" else ".proc\n"))
+        asmgen.outputSourceLine(block)
+
+        createBlockVariables(block)
+        asmsubs2asm(block.statements)
+
+        asmgen.out("")
+        asmgen.out("; subroutines in this block")
+
+        // First translate regular statements, and then put the subroutines at the end.
+        // (regular statements = everything except the initialization assignments;
+        // these will be part of the prog8_init_vars init routine generated below)
+        val initializers = blockVariableInitializers.getValue(block)
+        val statements = block.statements.filterNot { it in initializers }
+        val (subroutine, stmts) = statements.partition { it is Subroutine }
+        stmts.forEach { asmgen.translate(it) }
+        subroutine.forEach { asmgen.translate(it) }
+
+        if(!options.dontReinitGlobals) {
+            // generate subroutine to initialize block-level (global) variables
+            if (initializers.isNotEmpty()) {
+                asmgen.out("prog8_init_vars\t.proc\n")
+                initializers.forEach { assign -> asmgen.translate(assign) }
+                asmgen.out("  rts\n  .pend")
+            }
+        }
+
+        asmgen.out(if("force_output" in block.options()) "\n\t.bend\n" else "\n\t.pend\n")
+    }
+
+    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) {
+        val scope = symboltable.lookupOrElse(block.name) { throw AssemblyError("lookup") }
+        require(scope.type==StNodeType.BLOCK)
+        val varsInBlock = getVars(scope)
+
+        // Zeropage Variables
+        val varnames = varsInBlock.filter { it.value.type==StNodeType.STATICVAR }.map { it.value.scopedName }.toSet()
+        zeropagevars2asm(varnames)
+
+        // MemDefs and Consts
+        val mvs = varsInBlock
+            .filter { it.value.type==StNodeType.MEMVAR }
+            .map { it.value as StMemVar }
+        val consts = varsInBlock
+            .filter { it.value.type==StNodeType.CONSTANT }
+            .map { it.value as StConstant }
+        memdefsAndConsts2asm(mvs, consts)
+
+        // normal statically allocated variables
+        val variables = varsInBlock
+            .filter { it.value.type==StNodeType.STATICVAR && !allocator.isZpVar(it.value.scopedName) }
+            .map { it.value as StStaticVariable }
+        nonZpVariables2asm(variables)
+    }
+
+    internal fun translateSubroutine(sub: Subroutine) {
+        var onlyVariables = false
+
+        if(sub.inline) {
+            if(options.optimize) {
+                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("")
+
+        if(sub.isAsmSubroutine) {
+            if(sub.asmAddress!=null)
+                return  // already done at the memvars section
+
+            // asmsub with most likely just an inline asm in it
+            asmgen.out("${sub.name}\t.proc")
+            sub.statements.forEach { asmgen.translate(it) }
+            asmgen.out("  .pend\n")
+        } else {
+            // regular subroutine
+            asmgen.out("${sub.name}\t.proc")
+
+            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, program, 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, program, asmgen, sub.parameters[0].type, sub, variableAsmName = sub.parameters[0].name)
+                    val target2 = AsmAssignTarget(TargetStorageKind.VARIABLE, program, 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("  .pend\n")
+        }
+    }
+
+    private fun entrypointInitialization() {
+        asmgen.out("; program startup initialization")
+        asmgen.out("  cld")
+        if(!options.dontReinitGlobals) {
+            blockVariableInitializers.forEach {
+                if (it.value.isNotEmpty())
+                    asmgen.out("  jsr  ${it.key.name}.prog8_init_vars")
+            }
+        }
+
+        // string and array variables in zeropage that have initializer value, should be initialized
+        val stringVarsWithInitInZp = getZpStringVarsWithInitvalue()
+        val arrayVarsWithInitInZp = getZpArrayVarsWithInitvalue()
+        if(stringVarsWithInitInZp.isNotEmpty() || arrayVarsWithInitInZp.isNotEmpty()) {
+            asmgen.out("; zp str and array initializations")
+            stringVarsWithInitInZp.forEach {
+                val name = asmgen.asmVariableName(it.name)
+                asmgen.out("""
+                    lda  #<${name}
+                    ldy  #>${name}
+                    sta  P8ZP_SCRATCH_W1
+                    sty  P8ZP_SCRATCH_W1+1
+                    lda  #<${name}_init_value
+                    ldy  #>${name}_init_value
+                    jsr  prog8_lib.strcpy""")
+            }
+            arrayVarsWithInitInZp.forEach {
+                val size = it.alloc.size
+                val name = asmgen.asmVariableName(it.name)
+                asmgen.out("""
+                    lda  #<${name}_init_value
+                    ldy  #>${name}_init_value
+                    sta  cx16.r0L
+                    sty  cx16.r0H
+                    lda  #<${name}
+                    ldy  #>${name}
+                    sta  cx16.r1L
+                    sty  cx16.r1H
+                    lda  #<$size
+                    ldy  #>$size
+                    jsr  sys.memcopy""")
+            }
+            asmgen.out("  jmp  +")
+        }
+
+        stringVarsWithInitInZp.forEach {
+            val varname = asmgen.asmVariableName(it.name)+"_init_value"
+            outputStringvar(varname, it.value.second, it.value.first)
+        }
+
+        arrayVarsWithInitInZp.forEach {
+            val varname = asmgen.asmVariableName(it.name)+"_init_value"
+            arrayVariable2asm(varname, it.alloc.dt, it.value, null)
+        }
+
+        asmgen.out("""+       tsx
+                    stx  prog8_lib.orig_stackpointer    ; required for sys.exit()                    
+                    ldx  #255       ; init estack ptr
+                    clv
+                    clc""")
+    }
+
+    private class ZpStringWithInitial(
+        val name: List<String>,
+        val alloc: Zeropage.ZpAllocation,
+        val value: Pair<String, Encoding>
+    )
+
+    private class ZpArrayWithInitial(
+        val name: List<String>,
+        val alloc: Zeropage.ZpAllocation,
+        val value: StArray
+    )
+
+    private fun getZpStringVarsWithInitvalue(): Collection<ZpStringWithInitial> {
+        val result = mutableListOf<ZpStringWithInitial>()
+        val vars = allocator.zeropageVars.filter { it.value.dt==DataType.STR }
+        for (variable in vars) {
+            val svar = symboltable.lookup(variable.key) as StStaticVariable        // TODO faster in flat lookup table
+            if(svar.initialStringValue!=null)
+                result.add(ZpStringWithInitial(variable.key, variable.value, svar.initialStringValue!!))
+        }
+        return result
+    }
+
+    private fun getZpArrayVarsWithInitvalue(): Collection<ZpArrayWithInitial> {
+        val result = mutableListOf<ZpArrayWithInitial>()
+        val vars = allocator.zeropageVars.filter { it.value.dt in ArrayDatatypes }
+        for (variable in vars) {
+            val svar = symboltable.lookup(variable.key) as StStaticVariable        // TODO faster in flat lookup table
+            if(svar.initialArrayValue!=null)
+                result.add(ZpArrayWithInitial(variable.key, variable.value, svar.initialArrayValue!!))
+        }
+        return result
+    }
+
+    private fun zeropagevars2asm(varNames: Set<List<String>>) {
+        val zpVariables = allocator.zeropageVars.filter { it.key in varNames }
+        for ((scopedName, zpvar) in zpVariables) {
+            if (scopedName.size == 2 && scopedName[0] == "cx16" && scopedName[1][0] == 'r' && scopedName[1][1].isDigit())
+                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 ${zpvar.dt}")
+        }
+    }
+
+    private fun nonZpVariables2asm(variables: List<StStaticVariable>) {
+        asmgen.out("")
+        asmgen.out("; non-zeropage variables")
+        val (stringvars, othervars) = variables.partition { it.dt==DataType.STR }
+        stringvars.forEach {
+            outputStringvar(it.name, it.initialStringValue!!.second, it.initialStringValue!!.first)
+        }
+        othervars.sortedBy { it.type }.forEach {
+            staticVariable2asm(it)
+        }
+    }
+
+    private fun staticVariable2asm(variable: StStaticVariable) {
+        val name = variable.name
+        val initialValue: Number =
+            if(variable.initialNumericValue!=null) {
+                if(variable.dt== DataType.FLOAT)
+                    variable.initialNumericValue!!
+                else
+                    variable.initialNumericValue!!.toInt()
+            } else 0
+
+        when (variable.dt) {
+            DataType.UBYTE -> asmgen.out("$name\t.byte  ${initialValue.toHex()}")
+            DataType.BYTE -> asmgen.out("$name\t.char  $initialValue")
+            DataType.UWORD -> asmgen.out("$name\t.word  ${initialValue.toHex()}")
+            DataType.WORD -> asmgen.out("$name\t.sint  $initialValue")
+            DataType.FLOAT -> {
+                if(initialValue==0) {
+                    asmgen.out("$name\t.byte  0,0,0,0,0  ; float")
+                } else {
+                    val floatFill = compTarget.machine.getFloat(initialValue).makeFloatFillAsm()
+                    asmgen.out("$name\t.byte  $floatFill  ; float $initialValue")
+                }
+            }
+            DataType.STR -> {
+                throw AssemblyError("all string vars should have been interned into prog")
+            }
+            in ArrayDatatypes -> arrayVariable2asm(name, variable.dt, variable.initialArrayValue, variable.length)
+            else -> {
+                throw AssemblyError("weird dt")
+            }
+        }
+    }
+
+    private fun arrayVariable2asm(varname: String, dt: DataType, value: StArray?, orNumberOfZeros: Int?) {
+        when(dt) {
+            DataType.ARRAY_UB -> {
+                val data = makeArrayFillDataUnsigned(dt, value, orNumberOfZeros)
+                if (data.size <= 16)
+                    asmgen.out("$varname\t.byte  ${data.joinToString()}")
+                else {
+                    asmgen.out(varname)
+                    for (chunk in data.chunked(16))
+                        asmgen.out("  .byte  " + chunk.joinToString())
+                }
+            }
+            DataType.ARRAY_B -> {
+                val data = makeArrayFillDataSigned(dt, value, orNumberOfZeros)
+                if (data.size <= 16)
+                    asmgen.out("$varname\t.char  ${data.joinToString()}")
+                else {
+                    asmgen.out(varname)
+                    for (chunk in data.chunked(16))
+                        asmgen.out("  .char  " + chunk.joinToString())
+                }
+            }
+            DataType.ARRAY_UW -> {
+                val data = makeArrayFillDataUnsigned(dt, value, orNumberOfZeros)
+                if (data.size <= 16)
+                    asmgen.out("$varname\t.word  ${data.joinToString()}")
+                else {
+                    asmgen.out(varname)
+                    for (chunk in data.chunked(16))
+                        asmgen.out("  .word  " + chunk.joinToString())
+                }
+            }
+            DataType.ARRAY_W -> {
+                val data = makeArrayFillDataSigned(dt, value, orNumberOfZeros)
+                if (data.size <= 16)
+                    asmgen.out("$varname\t.sint  ${data.joinToString()}")
+                else {
+                    asmgen.out(varname)
+                    for (chunk in data.chunked(16))
+                        asmgen.out("  .sint  " + chunk.joinToString())
+                }
+            }
+            DataType.ARRAY_F -> {
+                val array = value ?: zeroFilledArray(orNumberOfZeros!!)
+                val floatFills = array.map {
+                    compTarget.machine.getFloat(it.number!!).makeFloatFillAsm()
+                }
+                asmgen.out(varname)
+                for (f in array.zip(floatFills))
+                    asmgen.out("  .byte  ${f.second}  ; float ${f.first}")
+            }
+            else -> throw AssemblyError("require array dt")
+        }
+    }
+
+    private fun zeroFilledArray(numElts: Int): StArray {
+        val values = mutableListOf<StArrayElement>()
+        repeat(numElts) {
+            values.add(StArrayElement(0.0, null))
+        }
+        return values
+    }
+
+    private fun memdefsAndConsts2asm(memvars: Collection<StMemVar>, consts: Collection<StConstant>) {
+        memvars.forEach {
+            asmgen.out("  ${it.name} = ${it.address.toHex()}")
+        }
+        consts.forEach {
+            if(it.dt==DataType.FLOAT)
+                asmgen.out("  ${it.name} = ${it.value}")
+            else
+                asmgen.out("  ${it.name} = ${it.value.toHex()}")
+        }
+    }
+
+    private fun asmsubs2asm(statements: List<Statement>) {
+        statements
+            .filter { it is Subroutine && it.isAsmSubroutine && it.asmAddress!=null }
+            .forEach { asmsub ->
+                asmsub as Subroutine
+                asmgen.out("  ${asmsub.name} = ${asmsub.asmAddress!!.toHex()}")
+            }
+    }
+
+    private fun outputStringvar(varname: String, encoding: Encoding, value: String) {
+        asmgen.out("$varname\t; $encoding:\"${value.escape().replace("\u0000", "<NULL>")}\"")
+        val bytes = compTarget.encodeString(value, encoding).plus(0.toUByte())
+        val outputBytes = bytes.map { "$" + it.toString(16).padStart(2, '0') }
+        for (chunk in outputBytes.chunked(16))
+            asmgen.out("  .byte  " + chunk.joinToString())
+    }
+
+    private fun makeArrayFillDataUnsigned(dt: DataType, value: StArray?, orNumberOfZeros: Int?): List<String> {
+        val array = value ?: zeroFilledArray(orNumberOfZeros!!)
+        return when (dt) {
+            DataType.ARRAY_UB ->
+                // byte array can never contain pointer-to types, so treat values as all integers
+                array.map {
+                    val number = it.number!!.toInt()
+                    "$"+number.toString(16).padStart(2, '0')
+                }
+            DataType.ARRAY_UW -> array.map {
+                if(it.number!=null) {
+                    "$" + it.number!!.toInt().toString(16).padStart(4, '0')
+                }
+                else if(it.addressOf!=null) {
+                    asmgen.asmSymbolName(it.addressOf!!)
+                }
+                else
+                    throw AssemblyError("weird array elt")
+            }
+            else -> throw AssemblyError("invalid dt")
+        }
+    }
+
+    private fun makeArrayFillDataSigned(dt: DataType, value: StArray?, orNumberOfZeros: Int?): List<String> {
+        val array = value ?: zeroFilledArray(orNumberOfZeros!!)
+        return when (dt) {
+            // byte array can never contain pointer-to types, so treat values as all integers
+            DataType.ARRAY_UB ->
+                array.map {
+                    val number = it.number!!.toInt()
+                    "$"+number.toString(16).padStart(2, '0')
+                }
+            DataType.ARRAY_B ->
+                array.map {
+                    val number = it.number!!.toInt()
+                    val hexnum = number.absoluteValue.toString(16).padStart(2, '0')
+                    if(number>=0)
+                        "$$hexnum"
+                    else
+                        "-$$hexnum"
+                }
+            DataType.ARRAY_UW -> array.map {
+                val number = it.number!!.toInt()
+                "$" + number.toString(16).padStart(4, '0')
+            }
+            DataType.ARRAY_W -> array.map {
+                val number = it.number!!.toInt()
+                val hexnum = number.absoluteValue.toString(16).padStart(4, '0')
+                if(number>=0)
+                    "$$hexnum"
+                else
+                    "-$$hexnum"
+            }
+            else -> throw AssemblyError("invalid dt")
+        }
+    }
+
+}

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

@@ -0,0 +1,137 @@
+package prog8.codegen.cpu6502
+
+import com.github.michaelbull.result.fold
+import com.github.michaelbull.result.onSuccess
+import prog8.code.StNode
+import prog8.code.StNodeType
+import prog8.code.StStaticVariable
+import prog8.code.SymbolTable
+import prog8.code.core.*
+
+
+internal class VariableAllocator(private val symboltable: SymbolTable,
+                                 private val options: CompilationOptions,
+                                 private val errors: IErrorReporter
+) {
+
+    private val zeropage = options.compTarget.machine.zeropage
+    private val memorySlabsInternal = mutableMapOf<String, Pair<UInt, UInt>>()
+    internal val memorySlabs: Map<String, Pair<UInt, UInt>> = memorySlabsInternal
+    internal val globalFloatConsts = mutableMapOf<Double, String>()     // all float values in the entire program (value -> varname)
+    internal val zeropageVars: Map<List<String>, Zeropage.ZpAllocation> = zeropage.allocatedVariables
+
+    init {
+        allocateZeropageVariables()
+    }
+
+    internal fun getMemorySlab(name: String) = memorySlabsInternal[name]
+
+    internal fun allocateMemorySlab(name: String, size: UInt, align: UInt) {
+        memorySlabsInternal[name] = Pair(size, align)
+    }
+
+    internal fun isZpVar(scopedName: List<String>) = scopedName in zeropage.allocatedVariables
+
+    internal fun getFloatAsmConst(number: Double): String {
+        val asmName = globalFloatConsts[number]
+        if(asmName!=null)
+            return asmName
+
+        val newName = "prog8_float_const_${globalFloatConsts.size}"
+        globalFloatConsts[number] = newName
+        return newName
+    }
+
+    /**
+     * Allocate variables into the Zeropage.
+     * The result should be retrieved from the current machine's zeropage object!
+     */
+    private fun allocateZeropageVariables() {
+        if(options.zeropage== ZeropageType.DONTUSE)
+            return
+
+        val allVariables = collectAllVariables(symboltable)
+
+        val numberOfAllocatableVariables = allVariables.size
+        val varsRequiringZp = allVariables.filter { it.zpwish == ZeropageWish.REQUIRE_ZEROPAGE }
+        val varsPreferringZp = allVariables.filter { it.zpwish == ZeropageWish.PREFER_ZEROPAGE }
+        val varsDontCare = allVariables.filter { it.zpwish == ZeropageWish.DONTCARE }
+        val numberOfExplicitNonZpVariables = allVariables.count { it.zpwish == ZeropageWish.NOT_IN_ZEROPAGE }
+        require(varsDontCare.size + varsRequiringZp.size + varsPreferringZp.size + numberOfExplicitNonZpVariables == numberOfAllocatableVariables)
+
+        var numVariablesAllocatedInZP = 0
+        var numberOfNonIntegerVariables = 0
+
+        varsRequiringZp.forEach { variable ->
+            val result = zeropage.allocate(
+                variable.scopedName,
+                variable.dt,
+                variable.length,
+                variable.position,
+                errors
+            )
+            result.fold(
+                success = {
+                    numVariablesAllocatedInZP++
+                },
+                failure = {
+                    errors.err(it.message!!, variable.position)
+                }
+            )
+        }
+
+        if(errors.noErrors()) {
+            varsPreferringZp.forEach { variable ->
+                val result = zeropage.allocate(
+                    variable.scopedName,
+                    variable.dt,
+                    variable.length,
+                    variable.position,
+                    errors
+                )
+                result.onSuccess { numVariablesAllocatedInZP++ }
+                //  no need to check for allocation error, if there is one, just allocate in normal system ram.
+            }
+
+            // 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 }) {
+                    if(variable.dt in IntegerDatatypes) {
+                        if(zeropage.free.isEmpty()) {
+                            break
+                        } else {
+                            val result = zeropage.allocate(
+                                variable.scopedName,
+                                variable.dt,
+                                variable.length,
+                                variable.position,
+                                errors
+                            )
+                            result.onSuccess { numVariablesAllocatedInZP++ }
+                        }
+                    } else
+                        numberOfNonIntegerVariables++
+                }
+            }
+        }
+
+        println("  number of allocated vars: $numberOfAllocatableVariables")
+        println("  put into zeropage: $numVariablesAllocatedInZP,  non-zp allocatable: ${numberOfNonIntegerVariables+numberOfExplicitNonZpVariables}")
+        println("  zeropage free space: ${zeropage.free.size} bytes")
+    }
+
+    private fun collectAllVariables(st: SymbolTable): Collection<StStaticVariable> {
+        val vars = mutableListOf<StStaticVariable>()
+        fun collect(node: StNode) {
+            for(child in node.children) {
+                if(child.value.type == StNodeType.STATICVAR)
+                    vars.add(child.value as StStaticVariable)
+                else
+                    collect(child.value)
+            }
+        }
+        collect(st)
+        return vars
+    }
+}

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

@@ -1,12 +1,10 @@
-package prog8.compiler.target.cpu6502.codegen.assignment
+package prog8.codegen.cpu6502.assignment
 
 import prog8.ast.Program
-import prog8.ast.base.*
 import prog8.ast.expressions.*
 import prog8.ast.statements.*
-import prog8.compilerinterface.IMemSizer
-import prog8.compiler.target.AssemblyError
-import prog8.compiler.target.cpu6502.codegen.AsmGen
+import prog8.code.core.*
+import prog8.codegen.cpu6502.AsmGen
 
 
 internal enum class TargetStorageKind {
@@ -59,9 +57,7 @@ internal class AsmAssignTarget(val kind: TargetStorageKind,
         fun fromAstAssignment(assign: Assignment, program: Program, asmgen: AsmGen): AsmAssignTarget {
             with(assign.target) {
                 val idt = inferType(program)
-                if(!idt.isKnown)
-                    throw AssemblyError("unknown dt")
-                val dt = idt.getOr(DataType.UNDEFINED)
+                val dt = idt.getOrElse { throw AssemblyError("unknown dt") }
                 when {
                     identifier != null -> {
                         val parameter = identifier!!.targetVarDecl(program)?.subroutineParameter
@@ -122,7 +118,7 @@ internal class AsmAssignSource(val kind: SourceStorageKind,
                                val array: ArrayIndexedExpression? = null,
                                val memory: DirectMemoryRead? = null,
                                val register: RegisterOrPair? = null,
-                               val number: NumericLiteralValue? = null,
+                               val number: NumericLiteral? = null,
                                val expression: Expression? = null
 )
 {
@@ -144,9 +140,9 @@ internal class AsmAssignSource(val kind: SourceStorageKind,
                 return AsmAssignSource(SourceStorageKind.LITERALNUMBER, program, asmgen, cv.type, number = cv)
 
             return when(value) {
-                is NumericLiteralValue -> AsmAssignSource(SourceStorageKind.LITERALNUMBER, program, asmgen, value.type, number = cv)
-                is StringLiteralValue -> throw AssemblyError("string literal value should not occur anymore for asm generation")
-                is ArrayLiteralValue -> throw AssemblyError("array literal value should not occur anymore for asm generation")
+                is NumericLiteral -> throw AssemblyError("should have been constant value")
+                is StringLiteral -> 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 IdentifierReference -> {
                     val parameter = value.targetVarDecl(program)?.subroutineParameter
                     if(parameter!=null && parameter.definingSubroutine!!.isAsmSubroutine)
@@ -166,33 +162,23 @@ internal class AsmAssignSource(val kind: SourceStorageKind,
                     AsmAssignSource(SourceStorageKind.MEMORY, program, asmgen, DataType.UBYTE, memory = value)
                 }
                 is ArrayIndexedExpression -> {
-                    val dt = value.inferType(program).getOr(DataType.UNDEFINED)
+                    val dt = value.inferType(program).getOrElse { throw AssemblyError("unknown dt") }
                     AsmAssignSource(SourceStorageKind.ARRAY, program, asmgen, dt, array = value)
                 }
-                is FunctionCall -> {
-                    when (val sub = value.target.targetStatement(program)) {
-                        is Subroutine -> {
-                            val returnType = sub.returntypes.zip(sub.asmReturnvaluesRegisters).firstOrNull { rr -> rr.second.registerOrPair != null || rr.second.statusflag!=null }?.first
-                                    ?: throw AssemblyError("can't translate zero return values in assignment")
+                is BuiltinFunctionCall -> {
+                    val returnType = value.inferType(program)
+                    AsmAssignSource(SourceStorageKind.EXPRESSION, program, asmgen, returnType.getOrElse { throw AssemblyError("unknown dt") }, expression = value)
+                }
+                is FunctionCallExpression -> {
+                    val sub = value.target.targetSubroutine(program)!!
+                    val returnType = sub.returntypes.zip(sub.asmReturnvaluesRegisters).firstOrNull { rr -> rr.second.registerOrPair != null || rr.second.statusflag!=null }?.first
+                            ?: throw AssemblyError("can't translate zero return values in assignment")
 
-                            AsmAssignSource(SourceStorageKind.EXPRESSION, program, asmgen, returnType, expression = value)
-                        }
-                        is BuiltinFunctionStatementPlaceholder -> {
-                            val returnType = value.inferType(program)
-                            if(!returnType.isKnown)
-                                throw AssemblyError("unknown dt")
-                            AsmAssignSource(SourceStorageKind.EXPRESSION, program, asmgen, returnType.getOr(DataType.UNDEFINED), expression = value)
-                        }
-                        else -> {
-                            throw AssemblyError("weird call")
-                        }
-                    }
+                    AsmAssignSource(SourceStorageKind.EXPRESSION, program, asmgen, returnType, expression = value)
                 }
                 else -> {
-                    val dt = value.inferType(program)
-                    if(!dt.isKnown)
-                        throw AssemblyError("unknown dt")
-                    AsmAssignSource(SourceStorageKind.EXPRESSION, program, asmgen, dt.getOr(DataType.UNDEFINED), expression = value)
+                    val returnType = value.inferType(program)
+                    AsmAssignSource(SourceStorageKind.EXPRESSION, program, asmgen, returnType.getOrElse { throw AssemblyError("unknown dt") }, expression = value)
                 }
             }
         }

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

@@ -1,20 +1,18 @@
-package prog8.compiler.target.cpu6502.codegen.assignment
+package prog8.codegen.cpu6502.assignment
 
 import prog8.ast.Program
-import prog8.ast.base.*
 import prog8.ast.expressions.*
 import prog8.ast.statements.*
-import prog8.ast.toHex
-import prog8.compiler.target.AssemblyError
-import prog8.compiler.target.cpu6502.codegen.AsmGen
-import prog8.compilerinterface.BuiltinFunctions
-import prog8.compilerinterface.CpuType
-import prog8.compilerinterface.builtinFunctionReturnType
+import prog8.code.core.*
+import prog8.codegen.cpu6502.AsmGen
+import prog8.codegen.cpu6502.VariableAllocator
+import prog8.compiler.builtinFunctionReturnType
 
 
-internal class AssignmentAsmGen(private val program: Program, private val asmgen: AsmGen) {
-
-    private val augmentableAsmGen = AugmentableAssignmentAsmGen(program, this, asmgen)
+internal class AssignmentAsmGen(private val program: Program, 
+                                private val asmgen: AsmGen, 
+                                private val allocator: VariableAllocator) {
+    private val augmentableAsmGen = AugmentableAssignmentAsmGen(program, this, asmgen, allocator)
 
     fun translate(assignment: Assignment) {
         val target = AsmAssignTarget.fromAstAssignment(assignment, program, asmgen)
@@ -88,7 +86,7 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                             assignRegisterpairWord(assign.target, RegisterOrPair.AY)
                         }
                         DataType.FLOAT -> {
-                            asmgen.out("  lda  #<$arrayVarName+$indexValue |  ldy  #>$arrayVarName+$indexValue")
+                            asmgen.out("  lda  #<($arrayVarName+$indexValue) |  ldy  #>($arrayVarName+$indexValue)")
                             assignFloatFromAY(assign.target)
                         }
                         else ->
@@ -125,17 +123,14 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
             SourceStorageKind.MEMORY -> {
                 fun assignViaExprEval(expression: Expression) {
                     assignExpressionToVariable(expression, "P8ZP_SCRATCH_W2", DataType.UWORD, assign.target.scope)
-                    if (asmgen.isTargetCpu(CpuType.CPU65c02))
-                        asmgen.out("  lda  (P8ZP_SCRATCH_W2)")
-                    else
-                        asmgen.out("  ldy  #0 |  lda  (P8ZP_SCRATCH_W2),y")
+                    asmgen.loadAFromZpPointerVar("P8ZP_SCRATCH_W2")
                     assignRegisterByte(assign.target, CpuRegister.A)
                 }
 
                 val value = assign.source.memory!!
                 when (value.addressExpression) {
-                    is NumericLiteralValue -> {
-                        val address = (value.addressExpression as NumericLiteralValue).number.toUInt()
+                    is NumericLiteral -> {
+                        val address = (value.addressExpression as NumericLiteral).number.toUInt()
                         assignMemoryByte(assign.target, address, null)
                     }
                     is IdentifierReference -> {
@@ -152,140 +147,7 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                 }
             }
             SourceStorageKind.EXPRESSION -> {
-                when(val value = assign.source.expression!!) {
-                    is AddressOf -> {
-                        val sourceName = asmgen.asmSymbolName(value.identifier)
-                        assignAddressOf(assign.target, sourceName)
-                    }
-                    is NumericLiteralValue -> throw AssemblyError("source kind should have been literalnumber")
-                    is IdentifierReference -> throw AssemblyError("source kind should have been variable")
-                    is ArrayIndexedExpression -> throw AssemblyError("source kind should have been array")
-                    is DirectMemoryRead -> throw AssemblyError("source kind should have been memory")
-                    is TypecastExpression -> assignTypeCastedValue(assign.target, value.type, value.expression, value)
-                    is FunctionCall -> {
-                        when (val sub = value.target.targetStatement(program)) {
-                            is Subroutine -> {
-                                asmgen.saveXbeforeCall(value)
-                                asmgen.translateFunctionCall(value, true)
-                                val returnValue = sub.returntypes.zip(sub.asmReturnvaluesRegisters).singleOrNull { it.second.registerOrPair!=null } ?:
-                                    sub.returntypes.zip(sub.asmReturnvaluesRegisters).single { it.second.statusflag!=null }
-                                when (returnValue.first) {
-                                    DataType.STR -> {
-                                        asmgen.restoreXafterCall(value)
-                                        when(assign.target.datatype) {
-                                            DataType.UWORD -> {
-                                                // assign the address of the string result value
-                                                assignRegisterpairWord(assign.target, RegisterOrPair.AY)
-                                            }
-                                            DataType.STR, DataType.ARRAY_UB, DataType.ARRAY_B -> {
-                                                // copy the actual string result into the target string variable
-                                                asmgen.out("""
-                                                    pha
-                                                    lda  #<${assign.target.asmVarname}
-                                                    sta  P8ZP_SCRATCH_W1
-                                                    lda  #>${assign.target.asmVarname}
-                                                    sta  P8ZP_SCRATCH_W1+1
-                                                    pla
-                                                    jsr  prog8_lib.strcpy""")
-                                            }
-                                            else -> throw AssemblyError("weird target dt")
-                                        }
-                                    }
-                                    DataType.FLOAT -> {
-                                        // float result from function sits in FAC1
-                                        asmgen.restoreXafterCall(value)
-                                        assignFAC1float(assign.target)
-                                    }
-                                    else -> {
-                                        // do NOT restore X register before assigning the result values first
-                                        when (returnValue.second.registerOrPair) {
-                                            RegisterOrPair.A -> assignRegisterByte(assign.target, CpuRegister.A)
-                                            RegisterOrPair.X -> assignRegisterByte(assign.target, CpuRegister.X)
-                                            RegisterOrPair.Y -> assignRegisterByte(assign.target, CpuRegister.Y)
-                                            RegisterOrPair.AX -> assignRegisterpairWord(assign.target, RegisterOrPair.AX)
-                                            RegisterOrPair.AY -> assignRegisterpairWord(assign.target, RegisterOrPair.AY)
-                                            RegisterOrPair.XY -> assignRegisterpairWord(assign.target, RegisterOrPair.XY)
-                                            else -> {
-                                                val sflag = returnValue.second.statusflag
-                                                if(sflag!=null)
-                                                    assignStatusFlagByte(assign.target, sflag)
-                                                else
-                                                    throw AssemblyError("should be just one register byte result value")
-                                            }
-                                        }
-                                        // we've processed the result value in the X register by now, so it's now finally safe to restore it
-                                        asmgen.restoreXafterCall(value)
-                                    }
-                                }
-                            }
-                            is BuiltinFunctionStatementPlaceholder -> {
-                                val signature = BuiltinFunctions.getValue(sub.name)
-                                asmgen.translateBuiltinFunctionCallExpression(value, signature, false, assign.target.register)
-                                if(assign.target.register==null) {
-                                    // still need to assign the result to the target variable/etc.
-                                    val returntype = builtinFunctionReturnType(sub.name, value.args, program)
-                                    if(!returntype.isKnown)
-                                        throw AssemblyError("unknown dt")
-                                    when(returntype.getOr(DataType.UNDEFINED)) {
-                                        in ByteDatatypes -> assignRegisterByte(assign.target, CpuRegister.A)            // function's byte result is in A
-                                        in WordDatatypes -> assignRegisterpairWord(assign.target, RegisterOrPair.AY)    // function's word result is in AY
-                                        DataType.STR -> {
-                                            when (assign.target.datatype) {
-                                                DataType.STR -> {
-                                                    asmgen.out("""
-                                                        pha
-                                                        lda  #<${assign.target.asmVarname}
-                                                        sta  P8ZP_SCRATCH_W1
-                                                        lda  #>${assign.target.asmVarname}
-                                                        sta  P8ZP_SCRATCH_W1+1
-                                                        pla
-                                                        jsr  prog8_lib.strcpy""")
-                                                }
-                                                DataType.UWORD -> assignRegisterpairWord(assign.target, RegisterOrPair.AY)
-                                                else -> throw AssemblyError("str return value type mismatch with target")
-                                            }
-                                        }
-                                        DataType.FLOAT -> {
-                                            // float result from function sits in FAC1
-                                            assignFAC1float(assign.target)
-                                        }
-                                        else -> throw AssemblyError("weird result type")
-                                    }
-                                }
-                            }
-                            else -> {
-                                throw AssemblyError("weird func call")
-                            }
-                        }
-                    }
-                    is PrefixExpression -> {
-                        // first assign the value to the target then apply the operator in place on the target.
-                        translateNormalAssignment(AsmAssignment(
-                            AsmAssignSource.fromAstSource(value.expression, program, asmgen),
-                            assign.target,
-                            false, program.memsizer, assign.position
-                        ))
-                        val target = virtualRegsToVariables(assign.target)
-                        when(value.operator) {
-                            "+" -> {}
-                            "-" -> augmentableAsmGen.inplaceNegate(target, target.datatype)
-                            "~" -> augmentableAsmGen.inplaceInvert(target, target.datatype)
-                            "not" -> augmentableAsmGen.inplaceBooleanNot(target, target.datatype)
-                            else -> throw AssemblyError("invalid prefix operator")
-                        }
-                    }
-                    else -> {
-                        // Everything else just evaluate via the stack.
-                        // (we can't use the assignment helper functions (assignExpressionTo...) to do it via registers here,
-                        // because the code here is the implementation of exactly that...)
-                        // TODO DON'T STACK-EVAL THIS... by using a temp var? so that it becomes augmentable assignment expression?
-                        asmgen.translateExpression(value)
-                        if (assign.target.datatype in WordDatatypes && assign.source.datatype in ByteDatatypes)
-                            asmgen.signExtendStackLsb(assign.source.datatype)
-                        if(assign.target.kind!=TargetStorageKind.STACK || assign.target.datatype != assign.source.datatype)
-                            assignStackValue(assign.target)
-                    }
-                }
+                assignExpression(assign)
             }
             SourceStorageKind.REGISTER -> {
                 asmgen.assignRegister(assign.source.register!!, assign.target)
@@ -297,6 +159,258 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
         }
     }
 
+    private fun assignExpression(assign: AsmAssignment) {
+        when(val value = assign.source.expression!!) {
+            is AddressOf -> {
+                val sourceName = asmgen.asmSymbolName(value.identifier)
+                assignAddressOf(assign.target, sourceName)
+            }
+            is NumericLiteral -> throw AssemblyError("source kind should have been literalnumber")
+            is IdentifierReference -> throw AssemblyError("source kind should have been variable")
+            is ArrayIndexedExpression -> throw AssemblyError("source kind should have been array")
+            is DirectMemoryRead -> throw AssemblyError("source kind should have been memory")
+            is TypecastExpression -> assignTypeCastedValue(assign.target, value.type, value.expression, value)
+            is FunctionCallExpression -> {
+                val sub = value.target.targetSubroutine(program)!!
+                asmgen.saveXbeforeCall(value)
+                asmgen.translateFunctionCall(value, true)
+                val returnValue = sub.returntypes.zip(sub.asmReturnvaluesRegisters).singleOrNull { it.second.registerOrPair!=null } ?:
+                sub.returntypes.zip(sub.asmReturnvaluesRegisters).single { it.second.statusflag!=null }
+                when (returnValue.first) {
+                    DataType.STR -> {
+                        asmgen.restoreXafterCall(value)
+                        when(assign.target.datatype) {
+                            DataType.UWORD -> {
+                                // assign the address of the string result value
+                                assignRegisterpairWord(assign.target, RegisterOrPair.AY)
+                            }
+                            DataType.STR, DataType.ARRAY_UB, DataType.ARRAY_B -> {
+                                throw AssemblyError("stringvalue assignment should have been replaced by a call to strcpy")
+                            }
+                            else -> throw AssemblyError("weird target dt")
+                        }
+                    }
+                    DataType.FLOAT -> {
+                        // float result from function sits in FAC1
+                        asmgen.restoreXafterCall(value)
+                        assignFAC1float(assign.target)
+                    }
+                    else -> {
+                        // do NOT restore X register before assigning the result values first
+                        when (returnValue.second.registerOrPair) {
+                            RegisterOrPair.A -> assignRegisterByte(assign.target, CpuRegister.A)
+                            RegisterOrPair.X -> assignRegisterByte(assign.target, CpuRegister.X)
+                            RegisterOrPair.Y -> assignRegisterByte(assign.target, CpuRegister.Y)
+                            RegisterOrPair.AX -> assignRegisterpairWord(assign.target, RegisterOrPair.AX)
+                            RegisterOrPair.AY -> assignRegisterpairWord(assign.target, RegisterOrPair.AY)
+                            RegisterOrPair.XY -> assignRegisterpairWord(assign.target, RegisterOrPair.XY)
+                            else -> {
+                                val sflag = returnValue.second.statusflag
+                                if(sflag!=null)
+                                    assignStatusFlagByte(assign.target, sflag)
+                                else
+                                    throw AssemblyError("should be just one register byte result value")
+                            }
+                        }
+                        // we've processed the result value in the X register by now, so it's now finally safe to restore it
+                        asmgen.restoreXafterCall(value)
+                    }
+                }
+            }
+            is BuiltinFunctionCall -> {
+                asmgen.translateBuiltinFunctionCallExpression(value, false, assign.target.register)
+                if(assign.target.register==null) {
+                    // still need to assign the result to the target variable/etc.
+                    val returntype = builtinFunctionReturnType(value.name)
+                    if(!returntype.isKnown)
+                        throw AssemblyError("unknown dt")
+                    when(returntype.getOr(DataType.UNDEFINED)) {
+                        in ByteDatatypes -> assignRegisterByte(assign.target, CpuRegister.A)            // function's byte result is in A
+                        in WordDatatypes -> assignRegisterpairWord(assign.target, RegisterOrPair.AY)    // function's word result is in AY
+                        DataType.STR -> {
+                            when (assign.target.datatype) {
+                                DataType.STR -> {
+                                    asmgen.out("""
+                                                        pha
+                                                        lda  #<${assign.target.asmVarname}
+                                                        sta  P8ZP_SCRATCH_W1
+                                                        lda  #>${assign.target.asmVarname}
+                                                        sta  P8ZP_SCRATCH_W1+1
+                                                        pla
+                                                        jsr  prog8_lib.strcpy""")
+                                }
+                                DataType.UWORD -> assignRegisterpairWord(assign.target, RegisterOrPair.AY)
+                                else -> throw AssemblyError("str return value type mismatch with target")
+                            }
+                        }
+                        DataType.FLOAT -> {
+                            // float result from function sits in FAC1
+                            assignFAC1float(assign.target)
+                        }
+                        else -> throw AssemblyError("weird result type")
+                    }
+                }
+            }
+            is PrefixExpression -> {
+                // first assign the value to the target then apply the operator in place on the target.
+                translateNormalAssignment(AsmAssignment(
+                    AsmAssignSource.fromAstSource(value.expression, program, asmgen),
+                    assign.target,
+                    false, program.memsizer, assign.position
+                ))
+                val target = virtualRegsToVariables(assign.target)
+                when(value.operator) {
+                    "+" -> {}
+                    "-" -> augmentableAsmGen.inplaceNegate(target, target.datatype)
+                    "~" -> augmentableAsmGen.inplaceInvert(target, target.datatype)
+                    "not" -> augmentableAsmGen.inplaceBooleanNot(target, target.datatype)
+                    else -> throw AssemblyError("invalid prefix operator")
+                }
+            }
+            is ContainmentCheck -> {
+                containmentCheckIntoA(value)
+                assignRegisterByte(assign.target, CpuRegister.A)
+            }
+            is PipeExpression -> {
+                asmgen.translatePipeExpression(value.source, value.segments, value, false, false)
+                val resultDt = value.inferType(program)
+                val register =
+                    if(resultDt.isBytes) RegisterOrPair.A
+                    else if(resultDt.isWords) RegisterOrPair.AY
+                    else if(resultDt istype DataType.FLOAT) RegisterOrPair.FAC1
+                    else throw AssemblyError("invalid dt")
+                asmgen.assignRegister(register, assign.target)
+            }
+            is BinaryExpression -> {
+                if(value.operator in ComparisonOperators) {
+                    // TODO real optimized code for comparison expressions that yield a boolean result value
+                    assignConstantByte(assign.target, 0)
+                    val origTarget = assign.target.origAstTarget
+                    if(origTarget!=null) {
+                        val assignTrue = AnonymousScope(mutableListOf(
+                            Assignment(origTarget, NumericLiteral.fromBoolean(true, assign.position), AssignmentOrigin.ASMGEN, assign.position)
+                        ), assign.position)
+                        val assignFalse = AnonymousScope(mutableListOf(), assign.position)
+                        val ifelse = IfElse(value.copy(), assignTrue, assignFalse, assign.position)
+                        ifelse.linkParents(value)
+                        asmgen.translate(ifelse)
+                    }
+                    else {
+                        // no orig ast assign target so can't use the workaround, so fallback to stack eval
+                        fallbackToStackEval(assign)
+                    }
+                } else {
+                    // All remaining binary expressions just evaluate via the stack for now.
+                    // (we can't use the assignment helper functions (assignExpressionTo...) to do it via registers here,
+                    // because the code here is the implementation of exactly that...)
+                    fallbackToStackEval(assign)
+                }
+            }
+            else -> throw AssemblyError("weird assignment value type $value")
+        }
+    }
+
+    private fun fallbackToStackEval(assign: AsmAssignment) {
+        // TODO DON'T STACK-EVAL... perhaps by using a temp var? so that it becomes augmentable assignment expression?
+        //      or don't try to solve it here in this one case and rather rewrite the whole stack based value evaluation.
+        // this routine is called for assigning a binaryexpression value:
+        // - if it's a boolean comparison expression and the workaround isn't possible (no origTarget ast node)
+        // - for all other binary expressions.
+        asmgen.translateExpression(assign.source.expression!!)
+        if (assign.target.datatype in WordDatatypes && assign.source.datatype in ByteDatatypes)
+            asmgen.signExtendStackLsb(assign.source.datatype)
+        if (assign.target.kind != TargetStorageKind.STACK || assign.target.datatype != assign.source.datatype)
+            assignStackValue(assign.target)
+    }
+
+    private fun containmentCheckIntoA(containment: ContainmentCheck) {
+        val elementDt = containment.element.inferType(program)
+        val variable = (containment.iterable as? IdentifierReference)?.targetVarDecl(program)
+            ?: throw AssemblyError("invalid containment iterable type")
+
+        if(variable.origin!=VarDeclOrigin.USERCODE) {
+            when(variable.datatype) {
+                DataType.STR -> {
+                    require(elementDt.isBytes)
+                    val stringVal = variable.value as StringLiteral
+                    val varname = asmgen.asmVariableName(containment.iterable as IdentifierReference)
+                    assignExpressionToRegister(containment.element, RegisterOrPair.A, elementDt istype DataType.BYTE)
+                    asmgen.saveRegisterLocal(CpuRegister.A, containment.definingSubroutine!!)
+                    assignAddressOf(AsmAssignTarget(TargetStorageKind.VARIABLE, program, asmgen, DataType.UWORD, containment.definingSubroutine, "P8ZP_SCRATCH_W1"), varname)
+                    asmgen.restoreRegisterLocal(CpuRegister.A)
+                    asmgen.out("  ldy  #${stringVal.value.length}")
+                    asmgen.out("  jsr  prog8_lib.containment_bytearray")
+                    return
+                }
+                DataType.ARRAY_F -> {
+                    // require(elementDt istype DataType.FLOAT)
+                    throw AssemblyError("containment check of floats not supported")
+                }
+                in ArrayDatatypes -> {
+                    require(elementDt.isInteger)
+                    val arrayVal = variable.value as ArrayLiteral
+                    val dt = elementDt.getOr(DataType.UNDEFINED)
+                    val varname = asmgen.asmVariableName(containment.iterable as IdentifierReference)
+                    when(dt) {
+                        in ByteDatatypes -> {
+                            assignExpressionToRegister(containment.element, RegisterOrPair.A, elementDt istype DataType.BYTE)
+                            asmgen.saveRegisterLocal(CpuRegister.A, containment.definingSubroutine!!)
+                            assignAddressOf(AsmAssignTarget(TargetStorageKind.VARIABLE, program, asmgen, DataType.UWORD, containment.definingSubroutine, "P8ZP_SCRATCH_W1"), varname)
+                            asmgen.restoreRegisterLocal(CpuRegister.A)
+                            asmgen.out("  ldy  #${arrayVal.value.size}")
+                            asmgen.out("  jsr  prog8_lib.containment_bytearray")
+                        }
+                        in WordDatatypes -> {
+                            assignExpressionToVariable(containment.element, "P8ZP_SCRATCH_W1", elementDt.getOr(DataType.UNDEFINED), containment.definingSubroutine)
+                            assignAddressOf(AsmAssignTarget(TargetStorageKind.VARIABLE, program, asmgen, DataType.UWORD, containment.definingSubroutine, "P8ZP_SCRATCH_W2"), varname)
+                            asmgen.out("  ldy  #${arrayVal.value.size}")
+                            asmgen.out("  jsr  prog8_lib.containment_wordarray")
+                        }
+                        else -> throw AssemblyError("invalid dt")
+                    }
+                    return
+                }
+                else -> throw AssemblyError("invalid dt")
+            }
+        }
+        val varname = asmgen.asmVariableName(containment.iterable as IdentifierReference)
+        when(variable.datatype) {
+            DataType.STR -> {
+                // use subroutine
+                assignExpressionToRegister(containment.element, RegisterOrPair.A, elementDt istype DataType.BYTE)
+                asmgen.saveRegisterLocal(CpuRegister.A, containment.definingSubroutine!!)
+                assignAddressOf(AsmAssignTarget(TargetStorageKind.VARIABLE, program, asmgen, DataType.UWORD, containment.definingSubroutine, "P8ZP_SCRATCH_W1"), varname)
+                asmgen.restoreRegisterLocal(CpuRegister.A)
+                val stringVal = variable.value as StringLiteral
+                asmgen.out("  ldy  #${stringVal.value.length}")
+                asmgen.out("  jsr  prog8_lib.containment_bytearray")
+                return
+            }
+            DataType.ARRAY_F -> {
+                throw AssemblyError("containment check of floats not supported")
+            }
+            DataType.ARRAY_B, DataType.ARRAY_UB -> {
+                val arrayVal = variable.value as ArrayLiteral
+                assignExpressionToRegister(containment.element, RegisterOrPair.A, elementDt istype DataType.BYTE)
+                asmgen.saveRegisterLocal(CpuRegister.A, containment.definingSubroutine!!)
+                assignAddressOf(AsmAssignTarget(TargetStorageKind.VARIABLE, program, asmgen, DataType.UWORD, containment.definingSubroutine, "P8ZP_SCRATCH_W1"), varname)
+                asmgen.restoreRegisterLocal(CpuRegister.A)
+                asmgen.out("  ldy  #${arrayVal.value.size}")
+                asmgen.out("  jsr  prog8_lib.containment_bytearray")
+                return
+            }
+            DataType.ARRAY_W, DataType.ARRAY_UW -> {
+                val arrayVal = variable.value as ArrayLiteral
+                assignExpressionToVariable(containment.element, "P8ZP_SCRATCH_W1", elementDt.getOr(DataType.UNDEFINED), containment.definingSubroutine)
+                assignAddressOf(AsmAssignTarget(TargetStorageKind.VARIABLE, program, asmgen, DataType.UWORD, containment.definingSubroutine, "P8ZP_SCRATCH_W2"), varname)
+                asmgen.out("  ldy  #${arrayVal.value.size}")
+                asmgen.out("  jsr  prog8_lib.containment_wordarray")
+                return
+            }
+            else -> throw AssemblyError("invalid dt")
+        }
+    }
+
     private fun assignStatusFlagByte(target: AsmAssignTarget, statusflag: Statusflag) {
         when(statusflag) {
             Statusflag.Pc -> {
@@ -317,9 +431,7 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
 
     private fun assignTypeCastedValue(target: AsmAssignTarget, targetDt: DataType, value: Expression, origTypeCastExpression: TypecastExpression) {
         val valueIDt = value.inferType(program)
-        if(!valueIDt.isKnown)
-            throw AssemblyError("unknown dt")
-        val valueDt = valueIDt.getOr(DataType.UNDEFINED)
+        val valueDt = valueIDt.getOrElse { throw AssemblyError("unknown dt") }
         if(valueDt==targetDt)
             throw AssemblyError("type cast to identical dt should have been removed")
 
@@ -341,16 +453,13 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
 
                     fun assignViaExprEval(addressExpression: Expression) {
                         asmgen.assignExpressionToVariable(addressExpression, "P8ZP_SCRATCH_W2", DataType.UWORD, null)
-                        if (asmgen.isTargetCpu(CpuType.CPU65c02))
-                            asmgen.out("  lda  (P8ZP_SCRATCH_W2)")
-                        else
-                            asmgen.out("  ldy  #0 |  lda  (P8ZP_SCRATCH_W2),y")
+                        asmgen.loadAFromZpPointerVar("P8ZP_SCRATCH_W2")
                         assignRegisterByte(target, CpuRegister.A)
                     }
 
                     when (value.addressExpression) {
-                        is NumericLiteralValue -> {
-                            val address = (value.addressExpression as NumericLiteralValue).number.toUInt()
+                        is NumericLiteral -> {
+                            val address = (value.addressExpression as NumericLiteral).number.toUInt()
                             assignMemoryByteIntoWord(target, address, null)
                             return
                         }
@@ -372,7 +481,7 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                     }
                 }
             }
-            is NumericLiteralValue -> throw AssemblyError("a cast of a literal value should have been const-folded away")
+            is NumericLiteral -> throw AssemblyError("a cast of a literal value should have been const-folded away")
             else -> {}
         }
 
@@ -450,6 +559,18 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
             }
         }
 
+        if(target.kind==TargetStorageKind.REGISTER) {
+            if(valueDt==DataType.FLOAT && target.datatype!=DataType.FLOAT) {
+                // have to typecast the float number on the fly down to an integer
+                assignExpressionToRegister(value, RegisterOrPair.FAC1, target.datatype in SignedDatatypes)
+                assignTypeCastedFloatFAC1("P8ZP_SCRATCH_W1", target.datatype)
+                assignVariableToRegister("P8ZP_SCRATCH_W1", target.register!!, target.datatype in SignedDatatypes)
+            } else {
+                assignExpressionToRegister(value, target.register!!, targetDt==DataType.BYTE || targetDt==DataType.WORD)
+            }
+            return
+        }
+
         if(targetDt==DataType.FLOAT && (target.register==RegisterOrPair.FAC1 || target.register==RegisterOrPair.FAC2)) {
             when(valueDt) {
                 DataType.UBYTE -> {
@@ -482,7 +603,7 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
     }
 
     private fun assignCastViaLsbFunc(value: Expression, target: AsmAssignTarget) {
-        val lsb = FunctionCall(IdentifierReference(listOf("lsb"), value.position), mutableListOf(value), value.position)
+        val lsb = BuiltinFunctionCall(IdentifierReference(listOf("lsb"), value.position), mutableListOf(value), value.position)
         lsb.linkParents(value.parent)
         val src = AsmAssignSource(SourceStorageKind.EXPRESSION, program, asmgen, DataType.UBYTE, expression = lsb)
         val assign = AsmAssignment(src, target, false, program.memsizer, value.position)
@@ -826,8 +947,8 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                         }
                         DataType.FLOAT -> {
                             asmgen.out("""
-                                lda  #<${target.asmVarname}+$scaledIdx
-                                ldy  #>${target.asmVarname}+$scaledIdx
+                                lda  #<(${target.asmVarname}+$scaledIdx)
+                                ldy  #>(${target.asmVarname}+$scaledIdx)
                                 jsr  floats.pop_float
                             """)
                         }
@@ -1039,8 +1160,8 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                                 ldy  #>$sourceName
                                 sta  P8ZP_SCRATCH_W1
                                 sty  P8ZP_SCRATCH_W1+1
-                                lda  #<${target.asmVarname}+$scaledIdx
-                                ldy  #>${target.asmVarname}+$scaledIdx
+                                lda  #<(${target.asmVarname}+$scaledIdx)
+                                ldy  #>(${target.asmVarname}+$scaledIdx)
                                 jsr  floats.copy_float
                             """)
                         }
@@ -1143,7 +1264,7 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
             TargetStorageKind.MEMORY -> throw AssemblyError("can't assign float to mem byte")
             TargetStorageKind.REGISTER -> {
                 if (target.register!! != RegisterOrPair.FAC1)
-                    throw AssemblyError("can't assign Fac1 float to another fac register")
+                    throw AssemblyError("can't assign Fac1 float to another register")
             }
             TargetStorageKind.STACK -> asmgen.out("  jsr  floats.push_fac1")
         }
@@ -1192,17 +1313,13 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
         when(target.kind) {
             TargetStorageKind.VARIABLE -> {
                 asmgen.out("""
-                    lda  $sourceName
-                    sta  ${target.asmVarname}
-                    lda  $sourceName+1
-                    sta  ${target.asmVarname}+1
-                    lda  $sourceName+2
-                    sta  ${target.asmVarname}+2
-                    lda  $sourceName+3
-                    sta  ${target.asmVarname}+3
-                    lda  $sourceName+4
-                    sta  ${target.asmVarname}+4
-                """)
+                    lda  #<$sourceName
+                    ldy  #>$sourceName
+                    sta  P8ZP_SCRATCH_W1
+                    sty  P8ZP_SCRATCH_W1+1
+                    lda  #<${target.asmVarname}
+                    ldy  #>${target.asmVarname}
+                    jsr  floats.copy_float""")
             }
             TargetStorageKind.ARRAY -> {
                 asmgen.out("""
@@ -1323,7 +1440,7 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                         pha
                         ora  #$7f
                         bmi  +
-                        ldx  #0
+                        lda  #0
 +                       tax
                         pla""")
                     RegisterOrPair.AY -> asmgen.out("""
@@ -1331,7 +1448,7 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                         pha
                         ora  #$7f
                         bmi  +
-                        ldy  #0
+                        lda  #0
 +                       tay
                         pla""")
                     RegisterOrPair.XY -> asmgen.out("""
@@ -1339,9 +1456,19 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                         tax 
                         ora  #$7f
                         bmi  +
-                        ldy  #0
+                        lda  #0
 +                       tay""")
-                    else -> throw AssemblyError("only reg pairs are words")
+                    in Cx16VirtualRegisters -> {
+                        val regname = wordtarget.register.name.lowercase()
+                        asmgen.out("""
+                            lda  $sourceName
+                            sta  cx16.$regname
+                            ora  #$7f
+                            bmi  +
+                            lda  #0
++                           sta  cx16.$regname+1""")
+                    }
+                    else -> throw AssemblyError("only reg pairs allowed as word target ${wordtarget.register}")
                 }
             }
             TargetStorageKind.STACK -> {
@@ -1392,7 +1519,14 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                     RegisterOrPair.AX -> asmgen.out("  ldx  #0 |  lda  $sourceName")
                     RegisterOrPair.AY -> asmgen.out("  ldy  #0 |  lda  $sourceName")
                     RegisterOrPair.XY -> asmgen.out("  ldy  #0 |  ldx  $sourceName")
-                    else -> throw AssemblyError("only reg pairs are words")
+                    in Cx16VirtualRegisters -> {
+                        val regname = wordtarget.register.name.lowercase()
+                        if(asmgen.isTargetCpu(CpuType.CPU65c02))
+                            asmgen.out("  lda  $sourceName |  sta  cx16.$regname |  stz  cx16.$regname+1")
+                        else
+                            asmgen.out("  lda  $sourceName |  sta  cx16.$regname |  lda  #0 |  sta  cx16.$regname+1")
+                    }
+                    else -> throw AssemblyError("only reg pairs allowed as word target")
                 }
             }
             TargetStorageKind.STACK -> {
@@ -1660,7 +1794,7 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                     asmgen.out("  stz  ${target.asmVarname} |  stz  ${target.asmVarname}+1")
                 }
                 TargetStorageKind.MEMORY -> {
-                    throw AssemblyError("no asm gen for assign word $word to memory ${target.memory}")
+                    throw AssemblyError("memory is bytes not words")
                 }
                 TargetStorageKind.ARRAY -> {
                     asmgen.loadScaledArrayIndexIntoRegister(target.array!!, DataType.UWORD, CpuRegister.Y)
@@ -1759,7 +1893,7 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                     asmgen.out("  stz  ${target.asmVarname} ")
                 }
                 TargetStorageKind.MEMORY -> {
-                    asmgen.out("  lda  #${byte.toHex()}")
+                    asmgen.out("  lda  #0")
                     storeRegisterAInMemoryAddress(target.memory!!)
                 }
                 TargetStorageKind.ARRAY -> {
@@ -1905,7 +2039,7 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                 }
                 TargetStorageKind.MEMORY -> throw AssemblyError("can't assign float to memory byte")
                 TargetStorageKind.REGISTER -> {
-                    val floatConst = asmgen.getFloatAsmConst(float)
+                    val floatConst = allocator.getFloatAsmConst(float)
                     when(target.register!!) {
                         RegisterOrPair.FAC1 -> asmgen.out("  lda  #<$floatConst  | ldy  #>$floatConst |  jsr  floats.MOVFM")
                         RegisterOrPair.FAC2 -> asmgen.out("  lda  #<$floatConst  | ldy  #>$floatConst |  jsr  floats.CONUPK")
@@ -1913,27 +2047,23 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                     }
                 }
                 TargetStorageKind.STACK -> {
-                    val floatConst = asmgen.getFloatAsmConst(float)
+                    val floatConst = allocator.getFloatAsmConst(float)
                     asmgen.out(" lda  #<$floatConst |  ldy  #>$floatConst |  jsr  floats.push_float")
                 }
             }
         } else {
             // non-zero value
-            val constFloat = asmgen.getFloatAsmConst(float)
+            val constFloat = allocator.getFloatAsmConst(float)
             when(target.kind) {
                 TargetStorageKind.VARIABLE -> {
                     asmgen.out("""
-                            lda  $constFloat
-                            sta  ${target.asmVarname}
-                            lda  $constFloat+1
-                            sta  ${target.asmVarname}+1
-                            lda  $constFloat+2
-                            sta  ${target.asmVarname}+2
-                            lda  $constFloat+3
-                            sta  ${target.asmVarname}+3
-                            lda  $constFloat+4
-                            sta  ${target.asmVarname}+4
-                        """)
+                        lda  #<$constFloat
+                        ldy  #>$constFloat
+                        sta  P8ZP_SCRATCH_W1
+                        sty  P8ZP_SCRATCH_W1+1
+                        lda  #<${target.asmVarname}
+                        ldy  #>${target.asmVarname}
+                        jsr  floats.copy_float""")
                 }
                 TargetStorageKind.ARRAY -> {
                     val arrayVarName = target.asmVarname
@@ -1941,17 +2071,13 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                     if (constIndex!=null) {
                         val indexValue = constIndex * program.memsizer.memorySize(DataType.FLOAT)
                         asmgen.out("""
-                            lda  $constFloat
-                            sta  $arrayVarName+$indexValue
-                            lda  $constFloat+1
-                            sta  $arrayVarName+$indexValue+1
-                            lda  $constFloat+2
-                            sta  $arrayVarName+$indexValue+2
-                            lda  $constFloat+3
-                            sta  $arrayVarName+$indexValue+3
-                            lda  $constFloat+4
-                            sta  $arrayVarName+$indexValue+4
-                        """)
+                            lda  #<$constFloat
+                            ldy  #>$constFloat
+                            sta  P8ZP_SCRATCH_W1
+                            sty  P8ZP_SCRATCH_W1+1
+                            lda  #<($arrayVarName+$indexValue)
+                            ldy  #>($arrayVarName+$indexValue)
+                            jsr  floats.copy_float""")
                     } else {
                         val asmvarname = asmgen.asmVariableName(target.array.indexer.indexExpr as IdentifierReference)
                         asmgen.out("""
@@ -1970,7 +2096,7 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                 }
                 TargetStorageKind.MEMORY -> throw AssemblyError("can't assign float to memory byte")
                 TargetStorageKind.REGISTER -> {
-                    val floatConst = asmgen.getFloatAsmConst(float)
+                    val floatConst = allocator.getFloatAsmConst(float)
                     when(target.register!!) {
                         RegisterOrPair.FAC1 -> asmgen.out("  lda  #<$floatConst  | ldy  #>$floatConst |  jsr  floats.MOVFM")
                         RegisterOrPair.FAC2 -> asmgen.out("  lda  #<$floatConst  | ldy  #>$floatConst |  jsr  floats.CONUPK")
@@ -1978,7 +2104,7 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                     }
                 }
                 TargetStorageKind.STACK -> {
-                    val floatConst = asmgen.getFloatAsmConst(float)
+                    val floatConst = allocator.getFloatAsmConst(float)
                     asmgen.out(" lda  #<$floatConst |  ldy  #>$floatConst |  jsr  floats.push_float")
                 }
             }
@@ -2134,58 +2260,20 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
 
     private fun storeRegisterAInMemoryAddress(memoryAddress: DirectMemoryWrite) {
         val addressExpr = memoryAddress.addressExpression
-        val addressLv = addressExpr as? NumericLiteralValue
+        val addressLv = addressExpr as? NumericLiteral
 
         fun storeViaExprEval() {
             when(addressExpr) {
-                is NumericLiteralValue, is IdentifierReference -> {
+                is NumericLiteral, is IdentifierReference -> {
                     assignExpressionToVariable(addressExpr, "P8ZP_SCRATCH_W2", DataType.UWORD, null)
-                    if (asmgen.isTargetCpu(CpuType.CPU65c02))
-                        asmgen.out("  sta  (P8ZP_SCRATCH_W2)")
-                    else
-                        asmgen.out("  ldy  #0 |  sta  (P8ZP_SCRATCH_W2),y")
+                    asmgen.storeAIntoZpPointerVar("P8ZP_SCRATCH_W2")
                 }
                 else -> {
                     // same as above but we need to save the A register
                     asmgen.out("  pha")
                     assignExpressionToVariable(addressExpr, "P8ZP_SCRATCH_W2", DataType.UWORD, null)
                     asmgen.out("  pla")
-                    if (asmgen.isTargetCpu(CpuType.CPU65c02))
-                        asmgen.out("  sta  (P8ZP_SCRATCH_W2)")
-                    else
-                        asmgen.out("  ldy  #0 |  sta  (P8ZP_SCRATCH_W2),y")
-                }
-            }
-        }
-
-        fun storeAIntoPointerVar(pointervar: IdentifierReference) {
-            val sourceName = asmgen.asmVariableName(pointervar)
-            val vardecl = pointervar.targetVarDecl(program)!!
-            val scopedName = vardecl.scopedName.joinToString(".")
-            if (asmgen.isTargetCpu(CpuType.CPU65c02)) {
-                if (asmgen.isZpVar(scopedName)) {
-                    // pointervar is already in the zero page, no need to copy
-                    asmgen.out("  sta  ($sourceName)")
-                } else {
-                    asmgen.out("""
-                    ldy  $sourceName
-                    sty  P8ZP_SCRATCH_W2
-                    ldy  $sourceName+1
-                    sty  P8ZP_SCRATCH_W2+1
-                    sta  (P8ZP_SCRATCH_W2)""")
-                }
-            } else {
-                if (asmgen.isZpVar(scopedName)) {
-                    // pointervar is already in the zero page, no need to copy
-                    asmgen.out(" ldy  #0 |  sta  ($sourceName),y")
-                } else {
-                    asmgen.out("""
-                    ldy  $sourceName
-                    sty  P8ZP_SCRATCH_W2
-                    ldy  $sourceName+1
-                    sty  P8ZP_SCRATCH_W2+1
-                    ldy  #0
-                    sta  (P8ZP_SCRATCH_W2),y""")
+                    asmgen.storeAIntoZpPointerVar("P8ZP_SCRATCH_W2")
                 }
             }
         }
@@ -2195,7 +2283,7 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                 asmgen.out("  sta  ${addressLv.number.toHex()}")
             }
             addressExpr is IdentifierReference -> {
-                storeAIntoPointerVar(addressExpr)
+                asmgen.storeAIntoPointerVar(addressExpr)
             }
             addressExpr is BinaryExpression -> {
                 if(!asmgen.tryOptimizedPointerAccessWithA(addressExpr, true))
@@ -2213,10 +2301,14 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
     }
 
     internal fun assignExpressionToVariable(expr: Expression, asmVarName: String, dt: DataType, scope: Subroutine?) {
-        val src = AsmAssignSource.fromAstSource(expr, program, asmgen)
-        val tgt = AsmAssignTarget(TargetStorageKind.VARIABLE, program, asmgen, dt, scope, variableAsmName = asmVarName)
-        val assign = AsmAssignment(src, tgt, false, program.memsizer, expr.position)
-        translateNormalAssignment(assign)
+        if(expr.inferType(program) istype DataType.FLOAT && dt!=DataType.FLOAT) {
+            throw AssemblyError("can't directly assign a FLOAT expression to an integer variable $expr")
+        } else {
+            val src = AsmAssignSource.fromAstSource(expr, program, asmgen)
+            val tgt = AsmAssignTarget(TargetStorageKind.VARIABLE, program, asmgen, dt, scope, variableAsmName = asmVarName)
+            val assign = AsmAssignment(src, tgt, false, program.memsizer, expr.position)
+            translateNormalAssignment(assign)
+        }
     }
 
     internal fun assignVariableToRegister(asmVarName: String, register: RegisterOrPair, signed: Boolean) {

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

@@ -1,18 +1,18 @@
-package prog8.compiler.target.cpu6502.codegen.assignment
+package prog8.codegen.cpu6502.assignment
 
 import prog8.ast.Program
-import prog8.ast.base.*
+import prog8.ast.base.FatalAstException
 import prog8.ast.expressions.*
 import prog8.ast.statements.Subroutine
-import prog8.ast.toHex
-import prog8.compiler.target.AssemblyError
-import prog8.compiler.target.cpu6502.codegen.AsmGen
-import prog8.compilerinterface.CpuType
+import prog8.code.core.*
+import prog8.codegen.cpu6502.AsmGen
+import prog8.codegen.cpu6502.VariableAllocator
 
 
 internal class AugmentableAssignmentAsmGen(private val program: Program,
                                            private val assignmentAsmGen: AssignmentAsmGen,
-                                           private val asmgen: AsmGen
+                                           private val asmgen: AsmGen,
+                                           private val allocator: VariableAllocator
 ) {
     fun translate(assign: AsmAssignment) {
         require(assign.isAugmentable)
@@ -23,9 +23,7 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                 // A = -A , A = +A, A = ~A, A = not A
                 val target = assignmentAsmGen.virtualRegsToVariables(assign.target)
                 val itype = value.inferType(program)
-                if(!itype.isKnown)
-                    throw AssemblyError("unknown dt")
-                val type = itype.getOr(DataType.UNDEFINED)
+                val type = itype.getOrElse { throw AssemblyError("unknown dt") }
                 when (value.operator) {
                     "+" -> {}
                     "-" -> inplaceNegate(target, type)
@@ -47,7 +45,7 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
             return inplaceModification(target, binExpr.operator, binExpr.right)
         }
 
-        if (binExpr.operator in associativeOperators) {
+        if (binExpr.operator in AssociativeOperators) {
             if (binExpr.right isSameAs astTarget) {
                 // A = 5 <operator> A
                 return inplaceModification(target, binExpr.operator, binExpr.left)
@@ -113,7 +111,7 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
             }
             if(leftBinExpr.right isSameAs astTarget) {
                 // X = (Left <oper> X) <oper> Something
-                if(leftBinExpr.operator in associativeOperators) {
+                if(leftBinExpr.operator in AssociativeOperators) {
                     inplaceModification(target, leftBinExpr.operator, leftBinExpr.left)
                     inplaceModification(target, binExpr.operator, binExpr.right)
                     return
@@ -125,7 +123,7 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
         if(leftBinExpr==null && rightBinExpr!=null) {
             if(rightBinExpr.left isSameAs astTarget) {
                 // X = Something <oper> (X <oper> Right)
-                if(binExpr.operator in associativeOperators) {
+                if(binExpr.operator in AssociativeOperators) {
                     inplaceModification(target, rightBinExpr.operator, rightBinExpr.right)
                     inplaceModification(target, binExpr.operator, binExpr.left)
                     return
@@ -135,7 +133,7 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
             }
             if(rightBinExpr.right isSameAs astTarget) {
                 // X = Something <oper> (Left <oper> X)
-                if(binExpr.operator in associativeOperators && rightBinExpr.operator in associativeOperators) {
+                if(binExpr.operator in AssociativeOperators && rightBinExpr.operator in AssociativeOperators) {
                     inplaceModification(target, rightBinExpr.operator, rightBinExpr.left)
                     inplaceModification(target, binExpr.operator, binExpr.left)
                     return
@@ -153,7 +151,7 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
         // the asm-gen code can deal with situations where you want to assign a byte into a word.
         // it will create the most optimized code to do this (so it type-extends for us).
         // But we can't deal with writing a word into a byte - explicit typeconversion is required
-        val value = if(program.memsizer.memorySize(origValue.inferType(program).getOr(DataType.UNDEFINED)) > program.memsizer.memorySize(target.datatype)) {
+        val value = if(program.memsizer.memorySize(origValue.inferType(program).getOrElse { throw AssemblyError("unknown dt") }) > program.memsizer.memorySize(target.datatype)) {
             val typecast = TypecastExpression(origValue, target.datatype, true, origValue.position)
             typecast.linkParents(origValue.parent)
             typecast
@@ -162,7 +160,7 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
             origValue
         }
 
-        val valueLv = (value as? NumericLiteralValue)?.number
+        val valueLv = (value as? NumericLiteral)?.number
         val ident = value as? IdentifierReference
         val memread = value as? DirectMemoryRead
 
@@ -175,7 +173,7 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                             ident != null -> inplaceModification_byte_variable_to_variable(target.asmVarname, target.datatype, operator, ident)
                             memread != null -> inplaceModification_byte_memread_to_variable(target.asmVarname, target.datatype, operator, memread)
                             value is TypecastExpression -> {
-                                if (tryRemoveRedundantCast(value, target, operator)) return
+                                if (tryInplaceModifyWithRemovedRedundantCast(value, target, operator)) return
                                 inplaceModification_byte_value_to_variable(target.asmVarname, target.datatype, operator, value)
                             }
                             else -> inplaceModification_byte_value_to_variable(target.asmVarname, target.datatype, operator, value)
@@ -187,7 +185,8 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                             ident != null -> inplaceModification_word_variable_to_variable(target.asmVarname, target.datatype, operator, ident)
                             memread != null -> inplaceModification_word_memread_to_variable(target.asmVarname, target.datatype, operator, memread)
                             value is TypecastExpression -> {
-                                if (tryRemoveRedundantCast(value, target, operator)) return
+                                if (tryInplaceModifyWithRemovedRedundantCast(value, target, operator))
+                                    return
                                 inplaceModification_word_value_to_variable(target.asmVarname, target.datatype, operator, value)
                             }
                             else -> inplaceModification_word_value_to_variable(target.asmVarname, target.datatype, operator, value)
@@ -198,7 +197,7 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                             valueLv != null -> inplaceModification_float_litval_to_variable(target.asmVarname, operator, valueLv.toDouble(), target.scope!!)
                             ident != null -> inplaceModification_float_variable_to_variable(target.asmVarname, operator, ident, target.scope!!)
                             value is TypecastExpression -> {
-                                if (tryRemoveRedundantCast(value, target, operator)) return
+                                if (tryInplaceModifyWithRemovedRedundantCast(value, target, operator)) return
                                 inplaceModification_float_value_to_variable(target.asmVarname, operator, value, target.scope!!)
                             }
                             else -> inplaceModification_float_value_to_variable(target.asmVarname, operator, value, target.scope!!)
@@ -210,15 +209,15 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
             TargetStorageKind.MEMORY -> {
                 val memory = target.memory!!
                 when (memory.addressExpression) {
-                    is NumericLiteralValue -> {
-                        val addr = (memory.addressExpression as NumericLiteralValue).number.toInt()
+                    is NumericLiteral -> {
+                        val addr = (memory.addressExpression as NumericLiteral).number.toInt()
                         // re-use code to assign a variable, instead this time, use a direct memory address
                         when {
                             valueLv != null -> inplaceModification_byte_litval_to_variable(addr.toHex(), DataType.UBYTE, operator, valueLv.toInt())
                             ident != null -> inplaceModification_byte_variable_to_variable(addr.toHex(), DataType.UBYTE, operator, ident)
                             memread != null -> inplaceModification_byte_memread_to_variable(addr.toHex(), DataType.UBYTE, operator, value)
                             value is TypecastExpression -> {
-                                if (tryRemoveRedundantCast(value, target, operator)) return
+                                if (tryInplaceModifyWithRemovedRedundantCast(value, target, operator)) return
                                 inplaceModification_byte_value_to_variable(addr.toHex(), DataType.UBYTE, operator, value)
                             }
                             else -> inplaceModification_byte_value_to_variable(addr.toHex(), DataType.UBYTE, operator, value)
@@ -230,14 +229,14 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                             valueLv != null -> inplaceModification_byte_litval_to_pointer(pointer, operator, valueLv.toInt())
                             ident != null -> inplaceModification_byte_variable_to_pointer(pointer, operator, ident)
                             value is TypecastExpression -> {
-                                if (tryRemoveRedundantCast(value, target, operator)) return
+                                if (tryInplaceModifyWithRemovedRedundantCast(value, target, operator)) return
                                 inplaceModification_byte_value_to_pointer(pointer, operator, value)
                             }
                             else -> inplaceModification_byte_value_to_pointer(pointer, operator, value)
                         }
                     }
                     else -> {
-                        // TODO OTHER EVALUATION HERE, don't use the estack to transfer the address to read/write from
+                        // TODO use some other evaluation here; don't use the estack to transfer the address to read/write from
                         asmgen.assignExpressionTo(memory.addressExpression, AsmAssignTarget(TargetStorageKind.STACK, program, asmgen, DataType.UWORD, memory.definingSubroutine))
                         asmgen.out("  jsr  prog8_lib.read_byte_from_address_on_stack |  sta  P8ZP_SCRATCH_B1")
                         when {
@@ -245,7 +244,7 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                             ident != null -> inplaceModification_byte_variable_to_variable("P8ZP_SCRATCH_B1", DataType.UBYTE, operator, ident)
                             memread != null -> inplaceModification_byte_memread_to_variable("P8ZP_SCRATCH_B1", DataType.UBYTE, operator, memread)
                             value is TypecastExpression -> {
-                                if (tryRemoveRedundantCast(value, target, operator)) return
+                                if (tryInplaceModifyWithRemovedRedundantCast(value, target, operator)) return
                                 inplaceModification_byte_value_to_variable("P8ZP_SCRATCH_B1", DataType.UBYTE, operator, value)
                             }
                             else -> inplaceModification_byte_value_to_variable("P8ZP_SCRATCH_B1", DataType.UBYTE, operator, value)
@@ -256,7 +255,7 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
             }
             TargetStorageKind.ARRAY -> {
                 with(target.array!!.indexer) {
-                    val indexNum = indexExpr as? NumericLiteralValue
+                    val indexNum = indexExpr as? NumericLiteral
                     val indexVar = indexExpr as? IdentifierReference
                     when {
                         indexNum!=null -> {
@@ -268,7 +267,7 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                                         ident != null -> inplaceModification_byte_variable_to_variable(targetVarName, target.datatype, operator, ident)
                                         memread != null -> inplaceModification_byte_memread_to_variable(targetVarName, target.datatype, operator, memread)
                                         value is TypecastExpression -> {
-                                            if (tryRemoveRedundantCast(value, target, operator)) return
+                                            if (tryInplaceModifyWithRemovedRedundantCast(value, target, operator)) return
                                             inplaceModification_byte_value_to_variable(targetVarName, target.datatype, operator, value)
                                         }
                                         else -> inplaceModification_byte_value_to_variable(targetVarName, target.datatype, operator, value)
@@ -280,7 +279,7 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                                         ident != null -> inplaceModification_word_variable_to_variable(targetVarName, target.datatype, operator, ident)
                                         memread != null -> inplaceModification_word_memread_to_variable(targetVarName, target.datatype, operator, memread)
                                         value is TypecastExpression -> {
-                                            if (tryRemoveRedundantCast(value, target, operator)) return
+                                            if (tryInplaceModifyWithRemovedRedundantCast(value, target, operator)) return
                                             inplaceModification_word_value_to_variable(targetVarName, target.datatype, operator, value)
                                         }
                                         else -> inplaceModification_word_value_to_variable(targetVarName, target.datatype, operator, value)
@@ -291,7 +290,7 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                                         valueLv != null -> inplaceModification_float_litval_to_variable(targetVarName, operator, valueLv.toDouble(), target.scope!!)
                                         ident != null -> inplaceModification_float_variable_to_variable(targetVarName, operator, ident, target.scope!!)
                                         value is TypecastExpression -> {
-                                            if (tryRemoveRedundantCast(value, target, operator)) return
+                                            if (tryInplaceModifyWithRemovedRedundantCast(value, target, operator)) return
                                             inplaceModification_float_value_to_variable(targetVarName, operator, value, target.scope!!)
                                         }
                                         else -> inplaceModification_float_value_to_variable(targetVarName, operator, value, target.scope!!)
@@ -350,12 +349,10 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
         }
     }
 
-    private fun tryRemoveRedundantCast(value: TypecastExpression, target: AsmAssignTarget, operator: String): Boolean {
+    private fun tryInplaceModifyWithRemovedRedundantCast(value: TypecastExpression, target: AsmAssignTarget, operator: String): Boolean {
         if (target.datatype == value.type) {
             val childIDt = value.expression.inferType(program)
-            if(!childIDt.isKnown)
-                throw AssemblyError("unknown dt")
-            val childDt = childIDt.getOr(DataType.UNDEFINED)
+            val childDt = childIDt.getOrElse { throw AssemblyError("unknown dt") }
             if (value.type!=DataType.FLOAT && (value.type.equalsSize(childDt) || value.type.largerThan(childDt))) {
                 // this typecast is redundant here; the rest of the code knows how to deal with the uncasted value.
                 // (works for integer types, not for float.)
@@ -368,13 +365,14 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
 
     private fun inplaceModification_byte_value_to_pointer(pointervar: IdentifierReference, operator: String, value: Expression) {
         asmgen.assignExpressionToVariable(value, "P8ZP_SCRATCH_B1", DataType.UBYTE, null)
+        val sourceName = asmgen.loadByteFromPointerIntoA(pointervar)
         when (operator) {
             // note: ** (power) operator requires floats.
             "+" -> asmgen.out("  clc |  adc  P8ZP_SCRATCH_B1")
             "-" -> asmgen.out("  sec |  sbc  P8ZP_SCRATCH_B1")
-            "*" -> asmgen.out("  ldy  P8ZP_SCRATCH_B1 |  jsr  math.multiply_bytes |  ldy  #0")
-            "/" -> asmgen.out("  ldy  P8ZP_SCRATCH_B1 |  jsr  math.divmod_ub_asm |  tya |  ldy  #0")
-            "%" -> asmgen.out("  ldy  P8ZP_SCRATCH_B1 |  jsr  math.divmod_ub_asm |  ldy  #0")
+            "*" -> asmgen.out("  ldy  P8ZP_SCRATCH_B1 |  jsr  math.multiply_bytes")
+            "/" -> asmgen.out("  ldy  P8ZP_SCRATCH_B1 |  jsr  math.divmod_ub_asm |  tya")
+            "%" -> asmgen.out("  ldy  P8ZP_SCRATCH_B1 |  jsr  math.divmod_ub_asm")
             "<<" -> {
                 asmgen.out("""
                     ldy  P8ZP_SCRATCH_B1
@@ -398,8 +396,7 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
             "^", "xor" -> asmgen.out(" eor  P8ZP_SCRATCH_B1")
             else -> throw AssemblyError("invalid operator for in-place modification $operator")
         }
-        val sourceName = asmgen.loadByteFromPointerIntoA(pointervar)
-        asmgen.out("  sta  ($sourceName),y")
+        asmgen.storeAIntoZpPointerVar(sourceName)
     }
 
     private fun inplaceModification_byte_variable_to_pointer(pointervar: IdentifierReference, operator: String, value: IdentifierReference) {
@@ -410,9 +407,9 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
             // note: ** (power) operator requires floats.
             "+" -> asmgen.out("  clc |  adc  $otherName")
             "-" -> asmgen.out("  sec |  sbc  $otherName")
-            "*" -> asmgen.out("  ldy  $otherName |  jsr  math.multiply_bytes |  ldy  #0")
-            "/" -> asmgen.out("  ldy  $otherName |  jsr  math.divmod_ub_asm |  tya |  ldy  #0")
-            "%" -> asmgen.out("  ldy  $otherName |  jsr  math.divmod_ub_asm |  ldy  #0")
+            "*" -> asmgen.out("  ldy  $otherName |  jsr  math.multiply_bytes")
+            "/" -> asmgen.out("  ldy  $otherName |  jsr  math.divmod_ub_asm |  tya")
+            "%" -> asmgen.out("  ldy  $otherName |  jsr  math.divmod_ub_asm")
             "<<" -> {
                 asmgen.out("""
                         ldy  $otherName
@@ -436,7 +433,7 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
             "^", "xor" -> asmgen.out(" eor  $otherName")
             else -> throw AssemblyError("invalid operator for in-place modification $operator")
         }
-        asmgen.out("  sta  ($sourceName),y")
+        asmgen.storeAIntoZpPointerVar(sourceName)
     }
 
     private fun inplaceModification_byte_litval_to_pointer(pointervar: IdentifierReference, operator: String, value: Int) {
@@ -445,63 +442,63 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
             "+" -> {
                 val sourceName = asmgen.loadByteFromPointerIntoA(pointervar)
                 asmgen.out("  clc |  adc  #$value")
-                asmgen.out("  sta  ($sourceName),y")
+                asmgen.storeAIntoZpPointerVar(sourceName)
             }
             "-" -> {
                 val sourceName = asmgen.loadByteFromPointerIntoA(pointervar)
                 asmgen.out("  sec |  sbc  #$value")
-                asmgen.out("  sta  ($sourceName),y")
+                asmgen.storeAIntoZpPointerVar(sourceName)
             }
             "*" -> {
                 val sourceName = asmgen.loadByteFromPointerIntoA(pointervar)
                 if(value in asmgen.optimizedByteMultiplications)
                     asmgen.out("  jsr  math.mul_byte_${value}")
                 else
-                    asmgen.out("  ldy  #$value |  jsr  math.multiply_bytes |  ldy  #0")
-                asmgen.out("  sta  ($sourceName),y")
+                    asmgen.out("  ldy  #$value |  jsr  math.multiply_bytes")
+                asmgen.storeAIntoZpPointerVar(sourceName)
             }
             "/" -> {
                 val sourceName = asmgen.loadByteFromPointerIntoA(pointervar)
                 if(value==0)
                     throw AssemblyError("division by zero")
-                asmgen.out("  ldy  #$value |  jsr  math.divmod_ub_asm |  tya |  ldy  #0")
-                asmgen.out("  sta  ($sourceName),y")
+                asmgen.out("  ldy  #$value |  jsr  math.divmod_ub_asm |  tya")
+                asmgen.storeAIntoZpPointerVar(sourceName)
             }
             "%" -> {
                 val sourceName = asmgen.loadByteFromPointerIntoA(pointervar)
                 if(value==0)
                     throw AssemblyError("division by zero")
-                asmgen.out("  ldy  #$value |  jsr  math.divmod_ub_asm |  ldy  #0")
-                asmgen.out("  sta  ($sourceName),y")
+                asmgen.out("  ldy  #$value |  jsr  math.divmod_ub_asm")
+                asmgen.storeAIntoZpPointerVar(sourceName)
             }
             "<<" -> {
                 if (value > 0) {
                     val sourceName = asmgen.loadByteFromPointerIntoA(pointervar)
-                    repeat(value) { asmgen.out(" asl  a") }
-                    asmgen.out("  sta  ($sourceName),y")
+                    repeat(value) { asmgen.out("  asl  a") }
+                    asmgen.storeAIntoZpPointerVar(sourceName)
                 }
             }
             ">>" -> {
                 if (value > 0) {
                     val sourceName = asmgen.loadByteFromPointerIntoA(pointervar)
-                    repeat(value) { asmgen.out(" lsr  a") }
-                    asmgen.out("  sta  ($sourceName),y")
+                    repeat(value) { asmgen.out("  lsr  a") }
+                    asmgen.storeAIntoZpPointerVar(sourceName)
                 }
             }
             "&", "and" -> {
                 val sourceName = asmgen.loadByteFromPointerIntoA(pointervar)
                 asmgen.out("  and  #$value")
-                asmgen.out("  sta  ($sourceName),y")
+                asmgen.storeAIntoZpPointerVar(sourceName)
             }
             "|", "or" -> {
                 val sourceName = asmgen.loadByteFromPointerIntoA(pointervar)
                 asmgen.out("  ora  #$value")
-                asmgen.out("  sta  ($sourceName),y")
+                asmgen.storeAIntoZpPointerVar(sourceName)
             }
             "^", "xor" -> {
                 val sourceName = asmgen.loadByteFromPointerIntoA(pointervar)
                 asmgen.out("  eor  #$value")
-                asmgen.out("  sta  ($sourceName),y")
+                asmgen.storeAIntoZpPointerVar(sourceName)
             }
             else -> throw AssemblyError("invalid operator for in-place modification $operator")
         }
@@ -578,6 +575,26 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                 asmgen.assignExpressionToRegister(value, RegisterOrPair.A)
                 asmgen.out("  eor  $name |  sta  $name")
             }
+            "==" -> {
+                asmgen.assignExpressionToRegister(value, RegisterOrPair.A)
+                asmgen.out("""
+                    cmp  $name
+                    beq  +
+                    lda  #0
+                    beq  ++
++                   lda  #1
++                   sta  $name""")
+            }
+            "!=" -> {
+                asmgen.assignExpressionToRegister(value, RegisterOrPair.A)
+                asmgen.out("""
+                    cmp  $name
+                    beq  +
+                    lda  #1
+                    bne  ++
++                   lda  #0
++                   sta  $name""")
+            }
             else -> throw AssemblyError("invalid operator for in-place modification $operator")
         }
     }
@@ -635,6 +652,26 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
             "&", "and" -> asmgen.out(" lda  $name |  and  $otherName |  sta  $name")
             "|", "or" -> asmgen.out(" lda  $name |  ora  $otherName |  sta  $name")
             "^", "xor" -> asmgen.out(" lda  $name |  eor  $otherName |  sta  $name")
+            "==" -> {
+                asmgen.out("""
+                    lda  $otherName
+                    cmp  $name
+                    beq  +
+                    lda  #0
+                    bne  ++
++                   lda  #1
++                   sta  $name""")
+            }
+            "!=" -> {
+                asmgen.out("""
+                    lda  $otherName
+                    cmp  $name
+                    beq  +
+                    lda  #1
+                    bne  ++
++                   lda  #0
++                   sta  $name""")
+            }
             else -> throw AssemblyError("invalid operator for in-place modification $operator")
         }
     }
@@ -706,6 +743,26 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
             "&", "and" -> asmgen.out(" lda  $name |  and  #$value |  sta  $name")
             "|", "or" -> asmgen.out(" lda  $name |  ora  #$value |  sta  $name")
             "^", "xor" -> asmgen.out(" lda  $name |  eor  #$value |  sta  $name")
+            "==" -> {
+                asmgen.out("""
+                    lda  $name
+                    cmp  #$value
+                    beq  +
+                    lda  #0
+                    beq  ++
++                   lda  #1
++                   sta  $name""")
+            }
+            "!=" -> {
+                asmgen.out("""
+                    lda  $name
+                    cmp  #$value
+                    beq  +
+                    lda  #1
+                    bne  ++
++                   lda  #0
++                   sta  $name""")
+            }
             else -> throw AssemblyError("invalid operator for in-place modification $operator")
         }
     }
@@ -1010,6 +1067,18 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                         else
                             asmgen.out("  lda  #0 |  sta  $name |  sta  $name+1")
                     }
+                    value == 0x00ff -> {
+                        if(asmgen.isTargetCpu(CpuType.CPU65c02))
+                            asmgen.out("  stz  $name+1")
+                        else
+                            asmgen.out("  lda  #0 |  sta  $name+1")
+                    }
+                    value == 0xff00 -> {
+                        if(asmgen.isTargetCpu(CpuType.CPU65c02))
+                            asmgen.out("  stz  $name")
+                        else
+                            asmgen.out("  lda  #0 |  sta  $name")
+                    }
                     value and 255 == 0 -> {
                         if(asmgen.isTargetCpu(CpuType.CPU65c02))
                             asmgen.out("  stz  $name")
@@ -1089,33 +1158,38 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
 +""")
                         else
                             asmgen.out("""
-                                ldy  #0
+                                ldy  #255
                                 lda  $otherName
                                 bpl  +
-                                dey     ; sign extend
-+                               sty  P8ZP_SCRATCH_B1
-                                lda  $name
+                                iny     ; sign extend
++                               eor  #255
                                 sec
-                                sbc  $otherName
+                                adc  $name
                                 sta  $name
-                                lda  $name+1
-                                sbc  P8ZP_SCRATCH_B1
+                                tya
+                                adc  $name+1
                                 sta  $name+1""")
                     }
                     "*" -> {
-                        asmgen.out("  lda  $otherName |  sta  P8ZP_SCRATCH_W1")
-                        if(asmgen.isTargetCpu(CpuType.CPU65c02))
-                            asmgen.out("  stz  P8ZP_SCRATCH_W1+1")
-                        else
-                            asmgen.out("  lda  #0 |  sta  P8ZP_SCRATCH_W1+1")
+                        if(valueDt==DataType.UBYTE) {
+                            asmgen.out("  lda  $otherName |  sta  P8ZP_SCRATCH_W1")
+                            if(asmgen.isTargetCpu(CpuType.CPU65c02))
+                                asmgen.out("  stz  P8ZP_SCRATCH_W1+1")
+                            else
+                                asmgen.out("  lda  #0 |  sta  P8ZP_SCRATCH_W1+1")
+                        } else {
+                            asmgen.out("  lda  $otherName")
+                            asmgen.signExtendAYlsb(valueDt)
+                            asmgen.out("  sta  P8ZP_SCRATCH_W1 |  sty  P8ZP_SCRATCH_W1+1")
+                        }
                         asmgen.out("""
-                            lda  $name
-                            ldy  $name+1
-                            jsr  math.multiply_words
-                            lda  math.multiply_words.result
-                            sta  $name
-                            lda  math.multiply_words.result+1
-                            sta  $name+1""")
+                                lda  $name
+                                ldy  $name+1
+                                jsr  math.multiply_words
+                                lda  math.multiply_words.result
+                                sta  $name
+                                lda  math.multiply_words.result+1
+                                sta  $name+1""")
                     }
                     "/" -> {
                         if(dt==DataType.UWORD) {
@@ -1292,9 +1366,7 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
         // because the value is evaluated onto the eval stack (=slow).
 
         val valueiDt = value.inferType(program)
-        if(!valueiDt.isKnown)
-            throw AssemblyError("unknown dt")
-        val valueDt = valueiDt.getOr(DataType.UNDEFINED)
+        val valueDt = valueiDt.getOrElse { throw AssemblyError("unknown dt") }
 
         fun multiplyVarByWordInAY() {
             asmgen.out("""
@@ -1373,29 +1445,28 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                                 sta  $name+1""")
                     }
                     "-" -> {
-                        asmgen.assignExpressionToVariable(value, "P8ZP_SCRATCH_REG", valueDt, null)
+                        asmgen.assignExpressionToVariable(value, "P8ZP_SCRATCH_B1", valueDt, null)
                         if(valueDt==DataType.UBYTE)
                             asmgen.out("""
                                 lda  $name
                                 sec
-                                sbc  P8ZP_SCRATCH_REG
+                                sbc  P8ZP_SCRATCH_B1
                                 sta  $name
                                 bcs  +
                                 dec  $name+1
 +""")
                         else
                             asmgen.out("""
-                                ldy  #0
-                                lda  P8ZP_SCRATCH_REG
+                                ldy  #255
+                                lda  P8ZP_SCRATCH_B1
                                 bpl  +
-                                dey         ; sign extend
-+                               sty  P8ZP_SCRATCH_B1
-                                lda  $name
+                                iny         ; sign extend
++                               eor  #255
                                 sec
-                                sbc  P8ZP_SCRATCH_REG
+                                adc  $name
                                 sta  $name
-                                lda  $name+1
-                                sbc  P8ZP_SCRATCH_B1
+                                tya
+                                adc  $name+1
                                 sta  $name+1""")
                     }
                     "*" -> {
@@ -1519,14 +1590,6 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
         asmgen.assignExpressionToRegister(value, RegisterOrPair.FAC1)
         asmgen.saveRegisterLocal(CpuRegister.X, scope)
         when (operator) {
-            "**" -> {
-                asmgen.out("""
-                    lda  #<$name
-                    ldy  #>$name
-                    jsr  floats.CONUPK
-                    jsr  floats.FPWRT
-                """)
-            }
             "+" -> {
                 asmgen.out("""
                     lda  #<$name
@@ -1573,28 +1636,6 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
         val otherName = asmgen.asmVariableName(ident)
         asmgen.saveRegisterLocal(CpuRegister.X, scope)
         when (operator) {
-            "**" -> {
-                if(asmgen.haveFPWR()) {
-                    asmgen.out("""
-                        lda  #<$name
-                        ldy  #>$name
-                        jsr  floats.CONUPK
-                        lda  #<$otherName
-                        ldy  #>$otherName
-                        jsr  floats.FPWR
-                    """)
-                } else
-                    // cx16 doesn't have FPWR() only FPWRT()
-                    asmgen.out("""
-                        lda  #<$name
-                        ldy  #>$name
-                        jsr  floats.CONUPK
-                        lda  #<$otherName
-                        ldy  #>$otherName
-                        jsr  floats.MOVFM
-                        jsr  floats.FPWRT
-                    """)
-            }
             "+" -> {
                 asmgen.out("""
                     lda  #<$name
@@ -1647,31 +1688,9 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
     }
 
     private fun inplaceModification_float_litval_to_variable(name: String, operator: String, value: Double, scope: Subroutine) {
-        val constValueName = asmgen.getFloatAsmConst(value)
+        val constValueName = allocator.getFloatAsmConst(value)
         asmgen.saveRegisterLocal(CpuRegister.X, scope)
         when (operator) {
-            "**" -> {
-                if(asmgen.haveFPWR()) {
-                    asmgen.out("""
-                        lda  #<$name
-                        ldy  #>$name
-                        jsr  floats.CONUPK
-                        lda  #<$constValueName
-                        ldy  #>$constValueName
-                        jsr  floats.FPWR
-                    """)
-                } else
-                    // cx16 doesn't have FPWR() only FPWRT()
-                    asmgen.out("""
-                        lda  #<$name
-                        ldy  #>$name
-                        jsr  floats.CONUPK
-                        lda  #<$constValueName
-                        ldy  #>$constValueName
-                        jsr  floats.MOVFM
-                        jsr  floats.FPWRT
-                    """)
-            }
             "+" -> {
                 if (value == 0.0)
                     return
@@ -1796,8 +1815,8 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                     TargetStorageKind.MEMORY -> {
                         val mem = target.memory!!
                         when (mem.addressExpression) {
-                            is NumericLiteralValue -> {
-                                val addr = (mem.addressExpression as NumericLiteralValue).number.toHex()
+                            is NumericLiteral -> {
+                                val addr = (mem.addressExpression as NumericLiteral).number.toHex()
                                 asmgen.out("""
                                     lda  $addr
                                     beq  +
@@ -1811,17 +1830,16 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                                     beq  +
                                     lda  #1
 +                                   eor  #1""")
-                                asmgen.out("  sta  ($sourceName),y")
+                                asmgen.storeAIntoZpPointerVar(sourceName)
                             }
                             else -> {
                                 asmgen.assignExpressionToVariable(mem.addressExpression, "P8ZP_SCRATCH_W2", DataType.UWORD, target.scope)
+                                asmgen.loadAFromZpPointerVar("P8ZP_SCRATCH_W2")
                                 asmgen.out("""
-                                    ldy  #0
-                                    lda  (P8ZP_SCRATCH_W2),y
                                     beq  +
                                     lda  #1
-+                                   eor  #1                                    
-                                    sta  (P8ZP_SCRATCH_W2),y""")
++                                   eor  #1""")
+                                asmgen.storeAIntoZpPointerVar("P8ZP_SCRATCH_W2")
                             }
                         }
                     }
@@ -1831,18 +1849,18 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                                 cmp  #0
                                 beq  +
                                 lda  #1
-    +                           eor  #1""")
++                               eor  #1""")
                             RegisterOrPair.X -> asmgen.out("""
                                 txa
                                 beq  +
                                 lda  #1
-    +                           eor  #1
++                               eor  #1
                                 tax""")
                             RegisterOrPair.Y -> asmgen.out("""
                                 tya
                                 beq  +
                                 lda  #1
-    +                           eor  #1
++                               eor  #1
                                 tay""")
                             else -> throw AssemblyError("invalid reg dt for byte not")
                         }
@@ -1925,8 +1943,8 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                     TargetStorageKind.MEMORY -> {
                         val memory = target.memory!!
                         when (memory.addressExpression) {
-                            is NumericLiteralValue -> {
-                                val addr = (memory.addressExpression as NumericLiteralValue).number.toHex()
+                            is NumericLiteral -> {
+                                val addr = (memory.addressExpression as NumericLiteral).number.toHex()
                                 asmgen.out("""
                                     lda  $addr
                                     eor  #255
@@ -1942,8 +1960,8 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                                 asmgen.out("""
                                     ldy  #0
                                     lda  (P8ZP_SCRATCH_W2),y
-                                    eor  #255
-                                    sta  (P8ZP_SCRATCH_W2),y""")
+                                    eor  #255""")
+                                asmgen.storeAIntoZpPointerVar("P8ZP_SCRATCH_W2")
                             }
                         }
                     }
@@ -2033,40 +2051,38 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                         when(target.register!!) { //P8ZP_SCRATCH_REG
                             RegisterOrPair.AX -> {
                                 asmgen.out("""
-                                    sta  P8ZP_SCRATCH_REG
-                                    stx  P8ZP_SCRATCH_REG+1
-                                    lda  #0
                                     sec
-                                    sbc  P8ZP_SCRATCH_REG
+                                    eor  #255
+                                    adc  #0
                                     pha
-                                    lda  #0
-                                    sbc  P8ZP_SCRATCH_REG+1
+                                    txa
+                                    eor  #255
+                                    adc  #0
                                     tax
                                     pla""")
                             }
                             RegisterOrPair.AY -> {
                                 asmgen.out("""
-                                    sta  P8ZP_SCRATCH_REG
-                                    sty  P8ZP_SCRATCH_REG+1
-                                    lda  #0
                                     sec
-                                    sbc  P8ZP_SCRATCH_REG
+                                    eor  #255
+                                    adc  #0
                                     pha
-                                    lda  #0
-                                    sbc  P8ZP_SCRATCH_REG+1
+                                    tya
+                                    eor  #255
+                                    adc  #0
                                     tay
                                     pla""")
                             }
                             RegisterOrPair.XY -> {
                                 asmgen.out("""
-                                    stx  P8ZP_SCRATCH_REG
-                                    sty  P8ZP_SCRATCH_REG+1
-                                    lda  #0
                                     sec
-                                    sbc  P8ZP_SCRATCH_REG
+                                    txa
+                                    eor  #255
+                                    adc  #0
                                     tax
-                                    lda  #0
-                                    sbc  P8ZP_SCRATCH_REG+1
+                                    tya
+                                    eor  #255
+                                    adc  #0
                                     tay""")
                             }
                             in Cx16VirtualRegisters -> throw AssemblyError("cx16 virtual regs should be variables, not real registers")
@@ -2087,7 +2103,7 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                             sta  ${target.asmVarname}+1
                         """)
                     }
-                    TargetStorageKind.STACK -> TODO("no asm gen for stack float negate")
+                    TargetStorageKind.STACK -> TODO("no asm gen for float stack negate")
                     else -> throw AssemblyError("weird target kind for inplace negate float ${target.kind}")
                 }
             }

codeGenExperimental/build.gradle

@@ -0,0 +1,46 @@
+
+plugins {
+    id 'java'
+    id 'application'
+    id "org.jetbrains.kotlin.jvm"
+}
+
+java {
+    toolchain {
+        languageVersion = JavaLanguageVersion.of(javaVersion)
+    }
+}
+
+compileKotlin {
+    kotlinOptions {
+        jvmTarget = javaVersion
+    }
+}
+
+compileTestKotlin {
+    kotlinOptions {
+        jvmTarget = javaVersion
+    }
+}
+
+dependencies {
+    implementation project(':codeAst')
+    implementation project(':codeCore')
+    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8"
+    // implementation "org.jetbrains.kotlin:kotlin-reflect"
+    implementation "com.michael-bull.kotlin-result:kotlin-result-jvm:1.1.14"
+
+}
+
+sourceSets {
+    main {
+        java {
+            srcDirs = ["${project.projectDir}/src"]
+        }
+        resources {
+            srcDirs = ["${project.projectDir}/res"]
+        }
+    }
+}
+
+// note: there are no unit tests in this module!

codeGenExperimental/codeGenExperimental.iml

@@ -0,0 +1,16 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<module type="JAVA_MODULE" version="4">
+  <component name="NewModuleRootManager" inherit-compiler-output="true">
+    <exclude-output />
+    <content url="file://$MODULE_DIR$">
+      <sourceFolder url="file://$MODULE_DIR$/src" isTestSource="false" />
+      <excludeFolder url="file://$MODULE_DIR$/build" />
+    </content>
+    <orderEntry type="inheritedJdk" />
+    <orderEntry type="sourceFolder" forTests="false" />
+    <orderEntry type="library" name="KotlinJavaRuntime" level="project" />
+    <orderEntry type="library" name="michael.bull.kotlin.result.jvm" level="project" />
+    <orderEntry type="module" module-name="codeAst" />
+    <orderEntry type="module" module-name="codeCore" />
+  </component>
+</module>

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

@@ -0,0 +1,39 @@
+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.IErrorReporter
+
+/*
+
+    NOTE: The goal is to keep the dependencies as lean as possible! For now, we depend only on:
+         - codeAst (the 'lean' new AST and the SymbolTable)
+         - codeCore (various base enums and interfaces)
+
+    This *should* be enough to build a complete code generator with. But we'll see :)
+
+ */
+
+
+class AsmGen(internal val program: PtProgram,
+             internal val symbolTable: SymbolTable,
+             internal val options: CompilationOptions,
+             internal val errors: IErrorReporter
+): IAssemblyGenerator {
+
+    override fun compileToAssembly(): IAssemblyProgram? {
+
+        println("\n** experimental code generator **\n")
+
+        println("Writing AST into XML form...")
+        val xmlConv = AstToXmlConverter(program, symbolTable, options)
+        xmlConv.writeXml()
+
+        println("..todo: create assembly program into ${options.outputDir.toAbsolutePath()}..")
+
+        return AssemblyProgram("dummy")
+    }
+}

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

@@ -0,0 +1,13 @@
+package prog8.codegen.experimental
+
+import prog8.code.core.CompilationOptions
+import prog8.code.core.IAssemblyProgram
+
+
+internal class AssemblyProgram(override val name: String) : IAssemblyProgram
+{
+    override fun assemble(options: CompilationOptions): Boolean {
+        println("..todo: assemble code into binary..")
+        return true
+    }
+}

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

@@ -0,0 +1,666 @@
+package prog8.codegen.experimental
+
+import prog8.code.*
+import prog8.code.ast.*
+import prog8.code.core.*
+import javax.xml.stream.XMLOutputFactory
+import kotlin.io.path.Path
+import kotlin.io.path.absolutePathString
+import kotlin.io.path.div
+
+/*
+
+    NOTE: The goal is to keep the dependencies as lean as possible! For now, we depend only on:
+         - codeAst (the 'lean' new AST and the SymbolTable)
+         - codeCore (various base enums and interfaces)
+
+    This *should* be enough to build a complete code generator with. But we'll see :)
+
+ */
+
+
+class AstToXmlConverter(internal val program: PtProgram,
+                        internal val symbolTable: SymbolTable,
+                        internal val options: CompilationOptions
+) {
+
+    private lateinit var xml: IndentingXmlWriter
+
+    fun writeXml() {
+        val writer = (options.outputDir / Path(program.name+"-ast.xml")).toFile().printWriter()
+        xml = IndentingXmlWriter(XMLOutputFactory.newFactory().createXMLStreamWriter(writer))
+        xml.doc()
+        xml.elt("program")
+        xml.attr("name", program.name)
+        xml.startChildren()
+        writeOptions(options)
+        program.children.forEach { writeNode(it) }
+        writeSymboltable(symbolTable)
+        xml.endElt()
+        xml.endDoc()
+        xml.close()
+    }
+
+    private fun writeSymboltable(st: SymbolTable) {
+        xml.elt("symboltable")
+        xml.startChildren()
+        st.flat.forEach{ (name, entry) ->
+            xml.elt("entry")
+            xml.attr("name", name.joinToString("."))
+            xml.attr("type", entry.type.name)
+            xml.startChildren()
+            writeStNode(entry)
+            xml.endElt()
+        }
+        xml.endElt()
+    }
+
+    private fun writeStNode(node: StNode) {
+        when(node.type) {
+            StNodeType.GLOBAL,
+            StNodeType.LABEL,
+            StNodeType.BLOCK,
+            StNodeType.BUILTINFUNC,
+            StNodeType.SUBROUTINE -> {/* no additional info*/}
+            StNodeType.ROMSUB -> {
+                node as StRomSub
+                xml.elt("romsub")
+                xml.attr("address", node.address.toString())
+                xml.endElt()
+            }
+            StNodeType.STATICVAR -> {
+                node as StStaticVariable
+                xml.elt("var")
+                xml.attr("type", node.dt.name)
+                xml.attr("zpwish", node.zpwish.name)
+                if(node.length!=null)
+                    xml.attr("length", node.length.toString())
+                if(node.initialNumericValue!=null || node.initialArrayValue!=null || node.initialStringValue!=null) {
+                    xml.startChildren()
+                    if(node.initialNumericValue!=null) {
+                        writeNumber(node.dt, node.initialNumericValue!!)
+                    }
+                    if(node.initialStringValue!=null) {
+                        xml.writeTextNode(
+                            "string",
+                            listOf(Pair("encoding", node.initialStringValue!!.second.name)),
+                            node.initialStringValue!!.first,
+                            false
+                        )
+                    }
+                    if(node.initialArrayValue!=null) {
+                        xml.elt("array")
+                        xml.startChildren()
+                        val eltDt = ArrayToElementTypes.getValue(node.dt)
+                        node.initialArrayValue!!.forEach {
+                            if(it.number!=null) {
+                                writeNumber(eltDt, it.number!!)
+                            }
+                            if(it.addressOf!=null) {
+                                xml.elt("addressof")
+                                xml.attr("symbol", it.addressOf!!.joinToString("."))
+                                xml.endElt()
+                            }
+                        }
+                        xml.endElt()
+                    }
+                }
+                xml.endElt()
+            }
+            StNodeType.MEMVAR -> {
+                node as StMemVar
+                xml.writeTextNode("memvar",
+                    listOf(Pair("type", node.dt.name)),
+                    node.address.toString(),
+                    false)
+            }
+            StNodeType.CONSTANT -> {
+                node as StConstant
+                xml.writeTextNode("const",
+                    listOf(Pair("type", node.dt.name)),
+                    intOrDouble(node.dt, node.value).toString(),
+                    false)
+            }
+        }
+    }
+
+    private fun writeOptions(options: CompilationOptions) {
+        xml.elt("options")
+        xml.attr("target", options.compTarget.name)
+        xml.attr("output", options.output.name)
+        xml.attr("launcher", options.launcher.name)
+        xml.attr("zeropage", options.zeropage.name)
+        xml.attr("loadaddress", options.loadAddress.toString())
+        xml.attr("floatsenabled", options.floats.toString())
+        xml.attr("nosysinit", options.noSysInit.toString())
+        xml.attr("dontreinitglobals", options.dontReinitGlobals.toString())
+        xml.attr("optimize", options.optimize.toString())
+        if(options.zpReserved.isNotEmpty()) {
+            xml.startChildren()
+            options.zpReserved.forEach {
+                xml.elt("zpreserved")
+                xml.attr("from", it.first.toString())
+                xml.attr("to", it.last.toString())
+                xml.endElt()
+            }
+        }
+        xml.endElt()
+    }
+
+    private fun writeNode(it: PtNode) {
+        when(it) {
+            is PtBlock -> write(it)
+            is PtSub -> write(it)
+            is PtVariable -> write(it)
+            is PtAssignment -> write(it)
+            is PtConstant -> write(it)
+            is PtAsmSub -> write(it)
+            is PtAddressOf -> write(it)
+            is PtArrayIndexer -> write(it)
+            is PtArray -> write(it)
+            is PtBinaryExpression -> write(it)
+            is PtBuiltinFunctionCall -> write(it)
+            is PtConditionalBranch -> write(it)
+            is PtContainmentCheck -> write(it)
+            is PtForLoop -> write(it)
+            is PtFunctionCall -> write(it)
+            is PtIdentifier -> write(it)
+            is PtIfElse -> write(it)
+            is PtInlineAssembly -> write(it)
+            is PtIncludeBinary -> write(it)
+            is PtJump -> write(it)
+            is PtMemoryByte -> write(it)
+            is PtMemMapped -> write(it)
+            is PtNumber -> write(it)
+            is PtPipe -> write(it)
+            is PtPostIncrDecr -> write(it)
+            is PtPrefix -> write(it)
+            is PtRange -> write(it)
+            is PtRepeatLoop -> write(it)
+            is PtReturn -> write(it)
+            is PtString -> write(it)
+            is PtTypeCast -> write(it)
+            is PtWhen -> write(it)
+            is PtWhenChoice -> write(it)
+            is PtLabel -> write(it)
+            is PtNop -> {}
+            is PtBreakpoint -> write(it)
+            is PtScopeVarsDecls -> write(it)
+            is PtNodeGroup -> it.children.forEach { writeNode(it) }
+            else -> TODO("$it")
+        }
+    }
+
+    private fun write(vars: PtScopeVarsDecls) {
+        xml.elt("vars")
+        xml.startChildren()
+        vars.children.forEach { writeNode(it) }
+        xml.endElt()
+    }
+
+    private fun write(breakPt: PtBreakpoint) {
+        xml.elt("breakpoint")
+        xml.pos(breakPt.position)
+        xml.endElt()
+    }
+
+    private fun write(pipe: PtPipe) {
+        xml.elt("pipe")
+        xml.attr("type", pipe.type.name)
+        xml.startChildren()
+        pipe.children.forEach { writeNode(it) }
+        xml.endElt()
+    }
+
+    private fun write(array: PtArray) {
+        xml.elt("array")
+        xml.attr("type", array.type.name)
+        xml.startChildren()
+        array.children.forEach { writeNode(it) }
+        xml.endElt()
+    }
+
+    private fun write(prefix: PtPrefix) {
+        xml.elt("prefix")
+        xml.attr("op", prefix.operator)
+        xml.attr("type", prefix.type.name)
+        xml.startChildren()
+        xml.elt("value")
+        xml.startChildren()
+        writeNode(prefix.value)
+        xml.endElt()
+        xml.endElt()
+    }
+
+    private fun write(string: PtString) =
+        xml.writeTextNode("string", listOf(Pair("encoding", string.encoding.name)), string.value, false)
+
+    private fun write(rept: PtRepeatLoop) {
+        xml.elt("repeat")
+        xml.pos(rept.position)
+        xml.startChildren()
+        xml.elt("count")
+        xml.startChildren()
+        writeNode(rept.count)
+        xml.endElt()
+        writeNode(rept.statements)
+        xml.endElt()
+    }
+
+    private fun write(branch: PtConditionalBranch) {
+        xml.elt("conditionalbranch")
+        xml.attr("condition", branch.condition.name)
+        xml.pos(branch.position)
+        xml.startChildren()
+        xml.elt("true")
+        xml.startChildren()
+        writeNode(branch.trueScope)
+        xml.endElt()
+        if(branch.falseScope.children.isNotEmpty()) {
+            xml.elt("false")
+            xml.startChildren()
+            writeNode(branch.falseScope)
+            xml.endElt()
+        }
+        xml.endElt()
+    }
+
+    private fun write(check: PtContainmentCheck) {
+        xml.elt("containment")
+        xml.attr("type", check.type.name)
+        xml.startChildren()
+        xml.elt("element")
+        xml.startChildren()
+        writeNode(check.children[0])
+        xml.endElt()
+        xml.elt("iterable")
+        xml.startChildren()
+        writeNode(check.children[1])
+        xml.endElt()
+        xml.endElt()
+    }
+
+    private fun write(range: PtRange) {
+        xml.elt("range")
+        xml.attr("type", range.type.name)
+        xml.startChildren()
+        xml.elt("from")
+        xml.startChildren()
+        writeNode(range.from)
+        xml.endElt()
+        xml.elt("to")
+        xml.startChildren()
+        writeNode(range.to)
+        xml.endElt()
+        xml.elt("step")
+        xml.startChildren()
+        writeNode(range.step)
+        xml.endElt()
+        xml.endElt()
+    }
+
+    private fun write(forLoop: PtForLoop) {
+        xml.elt("for")
+        xml.attr("loopvar", strTargetName(forLoop.variable))
+        xml.pos(forLoop.position)
+        xml.startChildren()
+        xml.elt("iterable")
+        xml.startChildren()
+        writeNode(forLoop.iterable)
+        xml.endElt()
+        writeNode(forLoop.statements)
+        xml.endElt()
+    }
+
+    private fun write(membyte: PtMemoryByte) {
+        xml.elt("membyte")
+        xml.attr("type", membyte.type.name)
+        xml.startChildren()
+        xml.elt("address")
+        xml.startChildren()
+        writeNode(membyte.address)
+        xml.endElt()
+        xml.endElt()
+    }
+
+    private fun write(whenStmt: PtWhen) {
+        xml.elt("when")
+        xml.pos(whenStmt.position)
+        xml.startChildren()
+        xml.elt("value")
+        xml.startChildren()
+        writeNode(whenStmt.value)
+        xml.endElt()
+        xml.elt("choices")
+        xml.startChildren()
+        writeNode(whenStmt.choices)
+        xml.endElt()
+        xml.endElt()
+    }
+
+    private fun write(choice: PtWhenChoice) {
+        xml.elt("choice")
+        if(choice.isElse) {
+            xml.attr("else", "true")
+            xml.startChildren()
+        } else {
+            xml.startChildren()
+            xml.elt("values")
+            xml.startChildren()
+            writeNode(choice.values)
+            xml.endElt()
+        }
+        writeNode(choice.statements)
+        xml.endElt()
+    }
+
+    private fun write(inlineAsm: PtInlineAssembly) {
+        xml.elt("assembly")
+        xml.pos(inlineAsm.position)
+        xml.startChildren()
+        xml.writeTextNode("code", emptyList(), inlineAsm.assembly)
+        xml.endElt()
+    }
+
+    private fun write(inlineBinary: PtIncludeBinary) {
+        xml.elt("binary")
+        xml.attr("filename", inlineBinary.file.absolutePathString())
+        if(inlineBinary.offset!=null)
+            xml.attr("offset", inlineBinary.offset!!.toString())
+        if(inlineBinary.length!=null)
+            xml.attr("length", inlineBinary.length!!.toString())
+        xml.pos(inlineBinary.position)
+        xml.endElt()
+    }
+
+    private fun write(fcall: PtBuiltinFunctionCall) {
+        xml.elt("builtinfcall")
+        xml.attr("name", fcall.name)
+        if(fcall.void)
+            xml.attr("type", "VOID")
+        else
+            xml.attr("type", fcall.type.name)
+        xml.startChildren()
+        fcall.children.forEach { writeNode(it) }
+        xml.endElt()
+    }
+
+    private fun write(cast: PtTypeCast) {
+        xml.elt("cast")
+        xml.attr("type", cast.type.name)
+        xml.startChildren()
+        writeNode(cast.value)
+        xml.endElt()
+    }
+
+    private fun write(aix: PtArrayIndexer) {
+        xml.elt("arrayindexed")
+        xml.attr("type", aix.type.name)
+        xml.startChildren()
+        write(aix.variable)
+        writeNode(aix.index)
+        xml.endElt()
+    }
+
+    private fun write(binexpr: PtBinaryExpression) {
+        xml.elt("binexpr")
+        xml.attr("op", binexpr.operator)
+        xml.attr("type", binexpr.type.name)
+        xml.startChildren()
+        writeNode(binexpr.left)
+        writeNode(binexpr.right)
+        xml.endElt()
+    }
+
+    private fun write(addrof: PtAddressOf) {
+        xml.elt("addressof")
+        xml.attr("symbol", strTargetName(addrof.identifier))
+        xml.endElt()
+    }
+
+    private fun write(fcall: PtFunctionCall) {
+        xml.elt("fcall")
+        xml.attr("name", strTargetName(fcall))
+        if(fcall.void)
+            xml.attr("type", "VOID")
+        else
+            xml.attr("type", fcall.type.name)
+        xml.pos(fcall.position)
+        xml.startChildren()
+        fcall.children.forEach { writeNode(it) }
+        xml.endElt()
+    }
+
+    private fun write(number: PtNumber) = writeNumber(number.type, number.number)
+
+    private fun writeNumber(type: DataType, number: Double) =
+        xml.writeTextNode("number", listOf(Pair("type", type.name)), intOrDouble(type, number).toString(), false)
+
+    private fun write(symbol: PtIdentifier) {
+        xml.elt("symbol")
+        xml.attr("name", strTargetName(symbol))
+        xml.attr("type", symbol.type.name)
+        xml.endElt()
+    }
+
+    private fun write(assign: PtAssignment) {
+        xml.elt("assign")
+        xml.pos(assign.position)
+        xml.startChildren()
+        write(assign.target)
+        writeNode(assign.value)
+        xml.endElt()
+    }
+
+    private fun write(ifElse: PtIfElse) {
+        xml.elt("ifelse")
+        xml.pos(ifElse.position)
+        xml.startChildren()
+        xml.elt("condition")
+        xml.startChildren()
+        writeNode(ifElse.condition)
+        xml.endElt()
+        xml.elt("true")
+        xml.pos(ifElse.ifScope.position)
+        xml.startChildren()
+        writeNode(ifElse.ifScope)
+        xml.endElt()
+        if(ifElse.elseScope.children.isNotEmpty()) {
+            xml.elt("false")
+            xml.pos(ifElse.elseScope.position)
+            xml.startChildren()
+            writeNode(ifElse.elseScope)
+            xml.endElt()
+        }
+        xml.endElt()
+    }
+
+    private fun write(ret: PtReturn) {
+        xml.elt("return")
+        if(ret.hasValue) {
+            xml.startChildren()
+            writeNode(ret.value!!)
+        }
+        xml.endElt()
+    }
+
+    private fun write(incdec: PtPostIncrDecr) {
+        if(incdec.operator=="++") xml.elt("inc") else xml.elt("dec")
+        xml.startChildren()
+        write(incdec.target)
+        xml.endElt()
+    }
+
+    private fun write(label: PtLabel) {
+        xml.elt("label")
+        xml.attr("name", label.scopedName.joinToString("."))
+        xml.pos(label.position)
+        xml.endElt()
+    }
+
+    private fun write(block: PtBlock) {
+        xml.elt("block")
+        xml.attr("name", block.scopedName.joinToString("."))
+        if(block.address!=null)
+            xml.attr("address", block.address!!.toString())
+        xml.attr("library", block.library.toString())
+        xml.pos(block.position)
+        xml.startChildren()
+        block.children.forEach { writeNode(it) }
+        xml.endElt()
+    }
+
+    private fun write(memMapped: PtMemMapped) {
+        xml.writeTextNode("memvar",
+            listOf(
+                Pair("name", memMapped.scopedName.joinToString(".")),
+                Pair("type", memMapped.type.name)
+            ),
+            memMapped.address.toString(),
+            false)
+    }
+
+    private fun write(target: PtAssignTarget) {
+        xml.elt("target")
+        xml.startChildren()
+        if(target.identifier!=null) {
+            writeNode(target.identifier!!)
+        } else if(target.memory!=null) {
+            writeNode(target.memory!!)
+        } else if(target.array!=null) {
+            writeNode(target.array!!)
+        } else
+            throw InternalCompilerException("weird assign target")
+        xml.endElt()
+    }
+
+    private fun write(jump: PtJump) {
+        xml.elt("jump")
+        if(jump.identifier!=null) xml.attr("symbol", strTargetName(jump.identifier!!))
+        else if(jump.address!=null) xml.attr("address", jump.address!!.toString())
+        else if(jump.generatedLabel!=null) xml.attr("label", jump.generatedLabel!!)
+        else
+            throw InternalCompilerException("weird jump target")
+        xml.endElt()
+    }
+
+    private fun write(sub: PtSub) {
+        xml.elt("sub")
+        xml.attr("name", sub.scopedName.joinToString("."))
+        if(sub.inline)
+            xml.attr("inline", "true")
+        xml.attr("returntype", sub.returntype?.toString() ?: "VOID")
+        xml.pos(sub.position)
+        xml.startChildren()
+        if(sub.parameters.isNotEmpty()) {
+            xml.elt("parameters")
+            xml.startChildren()
+            sub.parameters.forEach { write(it) }
+            xml.endElt()
+        }
+        sub.children.forEach { writeNode(it) }
+        xml.endElt()
+    }
+
+    private fun write(parameter: PtSubroutineParameter, registerOrStatusflag: RegisterOrStatusflag? = null) {
+        xml.elt("param")
+        xml.attr("name", parameter.name)
+        xml.attr("type", parameter.type.name)
+        if(registerOrStatusflag?.statusflag!=null) {
+            xml.attr("statusflag", registerOrStatusflag.statusflag!!.toString())
+        }
+        if(registerOrStatusflag?.registerOrPair!=null){
+            xml.attr("registers", registerOrStatusflag.registerOrPair!!.name)
+        }
+        xml.endElt()
+    }
+
+    private fun write(asmSub: PtAsmSub) {
+        if(asmSub.address!=null) {
+            xml.elt("romsub")
+            xml.attr("name", asmSub.scopedName.joinToString("."))
+            xml.attr("address", asmSub.address!!.toString())
+            if(asmSub.inline)
+                xml.attr("inline", "true")
+            xml.pos(asmSub.position)
+            xml.startChildren()
+            paramsEtcetera(asmSub)
+            xml.endElt()
+        }
+        else {
+            xml.elt("asmsub")
+            xml.attr("name", asmSub.scopedName.joinToString("."))
+            if(asmSub.inline)
+                xml.attr("inline", "true")
+            xml.pos(asmSub.position)
+            xml.startChildren()
+            paramsEtcetera(asmSub)
+            xml.elt("code")
+            xml.startChildren()
+            asmSub.children.forEach { writeNode(it) }
+            xml.endElt()
+            xml.endElt()
+        }
+    }
+
+    private fun paramsEtcetera(asmSub: PtAsmSub) {
+        if(asmSub.parameters.isNotEmpty()) {
+            xml.elt("parameters")
+            xml.startChildren()
+            asmSub.parameters.forEach { (param, reg) -> write(param, reg) }
+            xml.endElt()
+        }
+        if(asmSub.clobbers.isNotEmpty()) {
+            xml.elt("clobbers")
+            xml.attr("registers", asmSub.clobbers.joinToString(",") { it.name })
+            xml.endElt()
+        }
+        if(asmSub.retvalRegisters.isNotEmpty()) {
+            xml.elt("returns")
+            xml.startChildren()
+            asmSub.retvalRegisters.forEach {
+                xml.elt("register")
+                if(it.statusflag!=null)
+                    xml.attr("statusflag", it.statusflag!!.toString())
+                if(it.registerOrPair!=null)
+                    xml.attr("registers", it.registerOrPair!!.toString())
+                xml.endElt()
+            }
+            xml.endElt()
+        }
+    }
+
+    private fun write(constant: PtConstant) {
+        xml.writeTextNode("const",
+            listOf(
+                Pair("name", constant.scopedName.joinToString(".")),
+                Pair("type", constant.type.name)
+            ),
+            intOrDouble(constant.type, constant.value).toString(), false)
+    }
+
+    private fun write(variable: PtVariable) {
+        // the variable declaration nodes are still present in the Ast,
+        // but the Symboltable should be used look up their details.
+        xml.elt("vardecl")
+        xml.attr("name", variable.scopedName.joinToString("."))
+        xml.attr("type", variable.type.name)
+        if(variable.arraySize!=null)
+            xml.attr("arraysize", variable.arraySize.toString())
+        if(variable.value!=null) {
+            // static initialization value
+            xml.startChildren()
+            writeNode(variable.value!!)
+        }
+        xml.endElt()
+    }
+
+
+
+    private fun strTargetName(ident: PtIdentifier): String = ident.targetName.joinToString(".")
+
+    private fun strTargetName(call: PtFunctionCall): String = call.functionName.joinToString(".")
+
+    private fun intOrDouble(type: DataType, value: Double): Number =
+        if(type in IntegerDatatypes) value.toInt() else value
+}

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

@@ -0,0 +1,89 @@
+package prog8.codegen.experimental
+
+import prog8.code.core.Position
+import java.util.*
+import javax.xml.stream.XMLStreamWriter
+
+class IndentingXmlWriter(val xml: XMLStreamWriter): XMLStreamWriter by xml {
+    private var indent = 0
+    private var content = Stack<Boolean>()
+
+    fun doc(version: String? = null) = if(version==null) writeStartDocument() else writeStartDocument(version)
+    fun endDoc() = writeEndDocument()
+    fun elt(name: String) = writeStartElement(name)
+    fun attr(name: String, value: String) = writeAttribute(name, value)
+    fun attrs(attributes: List<Pair<String, String>>) = attributes.forEach { writeAttribute(it.first, it.second) }
+    fun startChildren() {
+        xml.writeCharacters("\n")
+        content.pop()
+        content.push(true)
+    }
+    fun endElt(writeIndent: Boolean=true) = writeEndElement(writeIndent)
+    fun pos(pos: Position) = writeAttribute("src", pos.toString())
+    fun comment(text: String) {
+        writeComment(text)
+        writeCharacters("\n")
+    }
+
+    override fun writeStartDocument() {
+        xml.writeStartDocument()
+        xml.writeCharacters("\n")
+        content.push(true)
+    }
+
+    override fun writeStartDocument(version: String) {
+        xml.writeStartDocument(version)
+        xml.writeCharacters("\n")
+        content.push(true)
+    }
+
+    override fun writeEndDocument() {
+        xml.writeEndDocument()
+        xml.writeCharacters("\n")
+        require(indent==0)
+        require(content.size==1)
+    }
+
+    override fun writeStartElement(name: String) {
+        xml.writeCharacters("  ".repeat(indent))
+        xml.writeStartElement(name)
+        indent++
+        content.push(false)
+    }
+
+    override fun writeStartElement(name: String, ns: String) {
+        xml.writeCharacters("  ".repeat(indent))
+        xml.writeStartElement(name, ns)
+        indent++
+        content.push(false)
+    }
+
+    fun writeEndElement(writeIndents: Boolean) {
+        indent--
+        if(content.pop() && writeIndents)
+            xml.writeCharacters("  ".repeat(indent))
+        xml.writeEndElement()
+        xml.writeCharacters("\n")
+    }
+
+    override fun writeEndElement() = writeEndElement(true)
+
+    override fun writeStartElement(name: String, ns: String, p2: String) {
+        xml.writeCharacters("  ".repeat(indent))
+        xml.writeStartElement(name, ns, p2)
+        indent++
+        content.push(false)
+    }
+
+    fun writeTextNode(name: String, attrs: List<Pair<String, String>>, text: String, cdata: Boolean = true) {
+        xml.writeCharacters("  ".repeat(indent))
+        xml.writeStartElement(name)
+        attrs.forEach { (name, value) -> xml.writeAttribute(name, value) }
+        if(cdata)
+            xml.writeCData(text)
+        else
+            xml.writeCharacters(text)
+        xml.writeEndElement()
+        xml.writeCharacters("\n")
+    }
+}

codeGenVirtual/build.gradle

@@ -0,0 +1,47 @@
+
+plugins {
+    id 'java'
+    id 'application'
+    id "org.jetbrains.kotlin.jvm"
+}
+
+java {
+    toolchain {
+        languageVersion = JavaLanguageVersion.of(javaVersion)
+    }
+}
+
+compileKotlin {
+    kotlinOptions {
+        jvmTarget = javaVersion
+    }
+}
+
+compileTestKotlin {
+    kotlinOptions {
+        jvmTarget = javaVersion
+    }
+}
+
+dependencies {
+    implementation project(':virtualmachine')
+    implementation project(':codeAst')
+    implementation project(':codeCore')
+    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8"
+    // implementation "org.jetbrains.kotlin:kotlin-reflect"
+    implementation "com.michael-bull.kotlin-result:kotlin-result-jvm:1.1.14"
+
+}
+
+sourceSets {
+    main {
+        java {
+            srcDirs = ["${project.projectDir}/src"]
+        }
+        resources {
+            srcDirs = ["${project.projectDir}/res"]
+        }
+    }
+}
+
+// note: there are no unit tests in this module!

codeGenVirtual/codeGenVirtual.iml

@@ -0,0 +1,16 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<module type="JAVA_MODULE" version="4">
+  <component name="NewModuleRootManager" inherit-compiler-output="true">
+    <exclude-output />
+    <content url="file://$MODULE_DIR$">
+      <sourceFolder url="file://$MODULE_DIR$/src" isTestSource="false" />
+    </content>
+    <orderEntry type="inheritedJdk" />
+    <orderEntry type="sourceFolder" forTests="false" />
+    <orderEntry type="library" name="KotlinJavaRuntime" level="project" />
+    <orderEntry type="library" name="michael.bull.kotlin.result.jvm" level="project" />
+    <orderEntry type="module" module-name="codeAst" />
+    <orderEntry type="module" module-name="codeCore" />
+    <orderEntry type="module" module-name="virtualmachine" />
+  </component>
+</module>

codeGenVirtual/src/prog8/codegen/virtual/AssemblyProgram.kt

@@ -0,0 +1,138 @@
+package prog8.codegen.virtual
+
+import prog8.code.core.AssemblyError
+import prog8.code.core.CompilationOptions
+import prog8.code.core.IAssemblyProgram
+import prog8.vm.Instruction
+import prog8.vm.Opcode
+import prog8.vm.OpcodesWithAddress
+import prog8.vm.VmDataType
+import java.io.BufferedWriter
+import java.nio.file.Path
+import kotlin.io.path.bufferedWriter
+import kotlin.io.path.div
+
+
+internal class AssemblyProgram(override val name: String,
+                               private val allocations: VariableAllocator
+) : IAssemblyProgram {
+
+    private val globalInits = mutableListOf<VmCodeLine>()
+    private val blocks = mutableListOf<VmCodeChunk>()
+
+    override fun assemble(options: CompilationOptions): Boolean {
+        val outfile = options.outputDir / ("$name.p8virt")
+        println("write code to $outfile")
+        outfile.bufferedWriter().use { out ->
+            allocations.asVmMemory().forEach { (name, alloc) ->
+                out.write("; ${name.joinToString(".")}\n")
+                out.write(alloc + "\n")
+            }
+            out.write("------PROGRAM------\n")
+
+            if(!options.dontReinitGlobals) {
+                out.write("; global var inits\n")
+                globalInits.forEach { out.writeLine(it) }
+            }
+
+            out.write("; actual program code\n")
+            blocks.asSequence().flatMap { it.lines }.forEach { line->out.writeLine(line) }
+        }
+        return true
+    }
+
+    private fun BufferedWriter.writeLine(line: VmCodeLine) {
+        when(line) {
+            is VmCodeComment -> write("; ${line.comment}\n")
+            is VmCodeInstruction -> {
+                write(line.ins.toString() + "\n")
+            }
+            is VmCodeLabel -> write("_" + line.name.joinToString(".") + ":\n")
+            is VmCodeInlineAsm -> {
+                val asm = line.assembly.replace("""\{[a-zA-Z\d_\.]+\}""".toRegex()) { matchResult ->
+                    val name = matchResult.value.substring(1, matchResult.value.length-1).split('.')
+                    allocations.get(name).toString() }
+                write(asm+"\n")
+            }
+            is VmCodeInlineBinary -> {
+                write("incbin \"${line.file}\"")
+                if(line.offset!=null)
+                    write(",${line.offset}")
+                if(line.length!=null)
+                    write(",${line.length}")
+                write("\n")
+            }
+            else -> throw AssemblyError("invalid vm code line")
+        }
+    }
+
+    fun addGlobalInits(chunk: VmCodeChunk) = globalInits.addAll(chunk.lines)
+    fun addBlock(block: VmCodeChunk) = blocks.add(block)
+}
+
+internal sealed class VmCodeLine
+
+internal class VmCodeInstruction(
+    opcode: Opcode,
+    type: VmDataType?=null,
+    reg1: Int?=null,        // 0-$ffff
+    reg2: Int?=null,        // 0-$ffff
+    fpReg1: Int?=null,      // 0-$ffff
+    fpReg2: Int?=null,      // 0-$ffff
+    value: Int?=null,       // 0-$ffff
+    fpValue: Float?=null,
+    labelSymbol: List<String>?=null    // alternative to value for branch/call/jump labels
+    ): VmCodeLine() {
+        val ins = Instruction(opcode, type, reg1, reg2, fpReg1, fpReg2, value, fpValue, labelSymbol)
+
+        init {
+            if(reg1!=null && (reg1<0 || reg1>65536))
+                throw IllegalArgumentException("reg1 out of bounds")
+            if(reg2!=null && (reg2<0 || reg2>65536))
+                throw IllegalArgumentException("reg2 out of bounds")
+            if(fpReg1!=null && (fpReg1<0 || fpReg1>65536))
+                throw IllegalArgumentException("fpReg1 out of bounds")
+            if(fpReg2!=null && (fpReg2<0 || fpReg2>65536))
+                throw IllegalArgumentException("fpReg2 out of bounds")
+
+            if(value!=null && opcode !in OpcodesWithAddress) {
+                when (type) {
+                    VmDataType.BYTE -> {
+                        if (value < -128 || value > 255)
+                            throw IllegalArgumentException("value out of range for byte: $value")
+                    }
+                    VmDataType.WORD -> {
+                        if (value < -32768 || value > 65535)
+                            throw IllegalArgumentException("value out of range for word: $value")
+                    }
+                    VmDataType.FLOAT, null -> {}
+                }
+            }
+        }
+    }
+
+internal class VmCodeLabel(val name: List<String>): VmCodeLine()
+internal class VmCodeComment(val comment: String): VmCodeLine()
+
+internal class VmCodeChunk(initial: VmCodeLine? = null) {
+    val lines = mutableListOf<VmCodeLine>()
+
+    init {
+        if(initial!=null)
+            lines.add(initial)
+    }
+
+    operator fun plusAssign(line: VmCodeLine) {
+        lines.add(line)
+    }
+
+    operator fun plusAssign(chunk: VmCodeChunk) {
+        lines.addAll(chunk.lines)
+    }
+}
+
+internal class VmCodeInlineAsm(asm: String): VmCodeLine() {
+    val assembly: String = asm.trimIndent()
+}
+
+internal class VmCodeInlineBinary(val file: Path, val offset: UInt?, val length: UInt?): VmCodeLine()

codeGenVirtual/src/prog8/codegen/virtual/AssignmentGen.kt

@@ -0,0 +1,232 @@
+package prog8.codegen.virtual
+
+import prog8.code.ast.*
+import prog8.code.core.AssemblyError
+import prog8.code.core.DataType
+import prog8.code.core.SignedDatatypes
+import prog8.vm.Opcode
+import prog8.vm.VmDataType
+
+internal class AssignmentGen(private val codeGen: CodeGen, private val expressionEval: ExpressionGen) {
+
+    internal fun translate(assignment: PtAssignment): VmCodeChunk {
+        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)
+            translateInplaceAssign(assignment)
+        else
+            translateRegularAssign(assignment)
+    }
+
+    private fun translateInplaceAssign(assignment: PtAssignment): VmCodeChunk {
+        val ident = assignment.target.identifier
+        val memory = assignment.target.memory
+        val array = assignment.target.array
+
+        return if(ident!=null) {
+            val address = codeGen.allocations.get(ident.targetName)
+            assignSelfInMemory(address, assignment.value, assignment)
+        } else if(memory != null) {
+            if(memory.address is PtNumber)
+                assignSelfInMemory((memory.address as PtNumber).number.toInt(), assignment.value, assignment)
+            else
+                fallbackAssign(assignment)
+        } else if(array!=null) {
+            // TODO in-place array element assignment?
+            fallbackAssign(assignment)
+        } else {
+            fallbackAssign(assignment)
+        }
+    }
+
+    private fun assignSelfInMemory(
+        address: Int,
+        value: PtExpression,
+        origAssign: PtAssignment
+    ): VmCodeChunk {
+        val vmDt = codeGen.vmType(value.type)
+        val code = VmCodeChunk()
+        when(value) {
+            is PtIdentifier -> return code // do nothing, x=x null assignment.
+            is PtMachineRegister -> return code // do nothing, reg=reg null assignment
+            is PtPrefix -> return inplacePrefix(value.operator, vmDt, address)
+            is PtBinaryExpression -> return inplaceBinexpr(value.operator, value.right, vmDt, value.type in SignedDatatypes, address, origAssign)
+            is PtMemoryByte -> {
+                return if (!codeGen.options.compTarget.machine.isIOAddress(address.toUInt()))
+                    code // do nothing, mem=mem null assignment.
+                else {
+                    // read and write a (i/o) memory location to itself.
+                    val tempReg = codeGen.vmRegisters.nextFree()
+                    code += VmCodeInstruction(Opcode.LOADM, vmDt, reg1 = tempReg, value = address)
+                    code += VmCodeInstruction(Opcode.STOREM, vmDt, reg1 = tempReg, value = address)
+                    code
+                }
+            }
+            else -> return fallbackAssign(origAssign)
+        }
+
+    }
+
+    private fun fallbackAssign(origAssign: PtAssignment): VmCodeChunk {
+        if (codeGen.options.slowCodegenWarnings)
+            codeGen.errors.warn("indirect code for in-place assignment", origAssign.position)
+        return translateRegularAssign(origAssign)
+    }
+
+    private fun inplaceBinexpr(
+        operator: String,
+        operand: PtExpression,
+        vmDt: VmDataType,
+        signed: Boolean,
+        address: Int,
+        origAssign: PtAssignment
+    ): VmCodeChunk {
+        when(operator) {
+            "+" -> return expressionEval.operatorPlusInplace(address, vmDt, operand)
+            "-" -> return expressionEval.operatorMinusInplace(address, vmDt, operand)
+            "*" -> return expressionEval.operatorMultiplyInplace(address, vmDt, operand)
+            "/" -> return expressionEval.operatorDivideInplace(address, vmDt, signed, operand)
+            "|" -> return expressionEval.operatorOrInplace(address, vmDt, operand)
+            "&" -> return expressionEval.operatorAndInplace(address, vmDt, operand)
+            "^" -> return expressionEval.operatorXorInplace(address, vmDt, operand)
+            "<<" -> return expressionEval.operatorShiftLeftInplace(address, vmDt, operand)
+            ">>" -> return expressionEval.operatorShiftRightInplace(address, vmDt, signed, operand)
+            else -> {}
+        }
+        return fallbackAssign(origAssign)
+    }
+
+    private fun inplacePrefix(operator: String, vmDt: VmDataType, address: Int): VmCodeChunk {
+        val code= VmCodeChunk()
+        when(operator) {
+            "+" -> { }
+            "-" -> {
+                code += VmCodeInstruction(Opcode.NEGM, vmDt, value = address)
+            }
+            "~" -> {
+                val regMask = codeGen.vmRegisters.nextFree()
+                val mask = if(vmDt==VmDataType.BYTE) 0x00ff else 0xffff
+                code += VmCodeInstruction(Opcode.LOAD, vmDt, reg1=regMask, value = mask)
+                code += VmCodeInstruction(Opcode.XORM, vmDt, reg1=regMask, value = address)
+            }
+            "not" -> {
+                code += VmCodeInstruction(Opcode.NOTM, vmDt, value = address)
+            }
+            else -> throw AssemblyError("weird prefix operator")
+        }
+        return code
+    }
+
+    private fun translateRegularAssign(assignment: PtAssignment): VmCodeChunk {
+        // note: assigning array and string values is done via an explicit memcopy/stringcopy function call.
+        val ident = assignment.target.identifier
+        val memory = assignment.target.memory
+        val array = assignment.target.array
+        val vmDt = codeGen.vmType(assignment.value.type)
+
+        val code = VmCodeChunk()
+        var resultRegister = -1
+        var resultFpRegister = -1
+        val zero = codeGen.isZero(assignment.value)
+        if(!zero) {
+            // calculate the assignment value
+            if (vmDt == VmDataType.FLOAT) {
+                resultFpRegister = codeGen.vmRegisters.nextFreeFloat()
+                code += expressionEval.translateExpression(assignment.value, -1, resultFpRegister)
+            } else {
+                resultRegister = if (assignment.value is PtMachineRegister) {
+                    (assignment.value as PtMachineRegister).register
+                } else {
+                    val reg = codeGen.vmRegisters.nextFree()
+                    code += expressionEval.translateExpression(assignment.value, reg, -1)
+                    reg
+                }
+            }
+        }
+        if(ident!=null) {
+            val address = codeGen.allocations.get(ident.targetName)
+            code += if(zero) {
+                VmCodeInstruction(Opcode.STOREZM, vmDt, value = address)
+            } else {
+                if (vmDt == VmDataType.FLOAT)
+                    VmCodeInstruction(Opcode.STOREM, vmDt, fpReg1 = resultFpRegister, value = address)
+                else
+                    VmCodeInstruction(Opcode.STOREM, vmDt, reg1 = resultRegister, value = address)
+            }
+        }
+        else if(array!=null) {
+            val variable = array.variable.targetName
+            var variableAddr = codeGen.allocations.get(variable)
+            val itemsize = codeGen.program.memsizer.memorySize(array.type)
+            val fixedIndex = constIntValue(array.index)
+            if(zero) {
+                if(fixedIndex!=null) {
+                    variableAddr += fixedIndex*itemsize
+                    code += VmCodeInstruction(Opcode.STOREZM, vmDt, value=variableAddr)
+                } else {
+                    val indexReg = codeGen.vmRegisters.nextFree()
+                    code += loadIndexReg(array, itemsize, indexReg)
+                    code += VmCodeInstruction(Opcode.STOREZX, vmDt, reg1=indexReg, value=variableAddr)
+                }
+            } else {
+                if(vmDt== VmDataType.FLOAT) {
+                    if(fixedIndex!=null) {
+                        variableAddr += fixedIndex*itemsize
+                        code += VmCodeInstruction(Opcode.STOREM, vmDt, fpReg1 = resultFpRegister, value=variableAddr)
+                    } else {
+                        val indexReg = codeGen.vmRegisters.nextFree()
+                        code += loadIndexReg(array, itemsize, indexReg)
+                        code += VmCodeInstruction(Opcode.STOREX, vmDt, reg1 = resultRegister, reg2=indexReg, value=variableAddr)
+                    }
+                } else {
+                    if(fixedIndex!=null) {
+                        variableAddr += fixedIndex*itemsize
+                        code += VmCodeInstruction(Opcode.STOREM, vmDt, reg1 = resultRegister, value=variableAddr)
+                    } else {
+                        val indexReg = codeGen.vmRegisters.nextFree()
+                        code += loadIndexReg(array, itemsize, indexReg)
+                        code += VmCodeInstruction(Opcode.STOREX, vmDt, reg1 = resultRegister, reg2=indexReg, value=variableAddr)
+                    }
+                }
+            }
+        }
+        else if(memory!=null) {
+            require(vmDt== VmDataType.BYTE)
+            if(zero) {
+                if(memory.address is PtNumber) {
+                    code += VmCodeInstruction(Opcode.STOREZM, vmDt, value=(memory.address as PtNumber).number.toInt())
+                } else {
+                    val addressReg = codeGen.vmRegisters.nextFree()
+                    code += expressionEval.translateExpression(memory.address, addressReg, -1)
+                    code += VmCodeInstruction(Opcode.STOREZI, vmDt, reg1=addressReg)
+                }
+            } else {
+                if(memory.address is PtNumber) {
+                    code += VmCodeInstruction(Opcode.STOREM, vmDt, reg1=resultRegister, value=(memory.address as PtNumber).number.toInt())
+                } else {
+                    val addressReg = codeGen.vmRegisters.nextFree()
+                    code += expressionEval.translateExpression(memory.address, addressReg, -1)
+                    code += VmCodeInstruction(Opcode.STOREI, vmDt, reg1=resultRegister, reg2=addressReg)
+                }
+            }
+        }
+        else
+            throw AssemblyError("weird assigntarget")
+        return code
+    }
+
+    private fun loadIndexReg(array: PtArrayIndexer, itemsize: Int, indexReg: Int): VmCodeChunk {
+        val code = VmCodeChunk()
+        if(itemsize==1) {
+            code += expressionEval.translateExpression(array.index, indexReg, -1)
+        }
+        else {
+            val mult = PtBinaryExpression("*", DataType.UBYTE, array.position)
+            mult.children += array.index
+            mult.children += PtNumber(DataType.UBYTE, itemsize.toDouble(), array.position)
+            code += expressionEval.translateExpression(mult, indexReg, -1)
+        }
+        return code
+    }
+}

codeGenVirtual/src/prog8/codegen/virtual/BuiltinFuncGen.kt

@@ -0,0 +1,390 @@
+package prog8.codegen.virtual
+
+import prog8.code.StStaticVariable
+import prog8.code.ast.*
+import prog8.code.core.AssemblyError
+import prog8.code.core.DataType
+import prog8.vm.Opcode
+import prog8.vm.Syscall
+import prog8.vm.VmDataType
+
+internal class BuiltinFuncGen(private val codeGen: CodeGen, private val exprGen: ExpressionGen) {
+
+    fun translate(call: PtBuiltinFunctionCall, resultRegister: Int): VmCodeChunk {
+        return when(call.name) {
+            "any" -> funcAny(call, resultRegister)
+            "all" -> funcAll(call, resultRegister)
+            "abs" -> funcAbs(call, resultRegister)
+            "cmp" -> funcCmp(call)
+            "sgn" -> funcSgn(call, resultRegister)
+            "sqrt16" -> funcSqrt16(call, resultRegister)
+            "pop" -> funcPop(call)
+            "popw" -> funcPopw(call)
+            "push" -> funcPush(call)
+            "pushw" -> funcPushw(call)
+            "rsave",
+            "rsavex",
+            "rrestore",
+            "rrestorex" -> VmCodeChunk() // vm doesn't have registers to save/restore
+            "rnd" -> funcRnd(resultRegister)
+            "rndw" -> funcRndw(resultRegister)
+            "callfar" -> throw AssemblyError("callfar() is for cx16 target only")
+            "callrom" -> throw AssemblyError("callrom() is for cx16 target only")
+            "msb" -> funcMsb(call, resultRegister)
+            "lsb" -> funcLsb(call, resultRegister)
+            "memory" -> funcMemory(call, resultRegister)
+            "peek" -> funcPeek(call, resultRegister)
+            "peekw" -> funcPeekW(call, resultRegister)
+            "poke" -> funcPoke(call)
+            "pokew" -> funcPokeW(call)
+            "pokemon" -> VmCodeChunk()
+            "mkword" -> funcMkword(call, resultRegister)
+            "sort" -> funcSort(call)
+            "reverse" -> funcReverse(call)
+            "swap" -> funcSwap(call)
+            "rol" -> funcRolRor2(Opcode.ROXL, call, resultRegister)
+            "ror" -> funcRolRor2(Opcode.ROXR, call, resultRegister)
+            "rol2" -> funcRolRor2(Opcode.ROL, call, resultRegister)
+            "ror2" -> funcRolRor2(Opcode.ROR, call, resultRegister)
+            else -> TODO("builtinfunc ${call.name}")
+        }
+    }
+
+    private fun funcCmp(call: PtBuiltinFunctionCall): VmCodeChunk {
+        val code = VmCodeChunk()
+        val leftRegister = codeGen.vmRegisters.nextFree()
+        val rightRegister = codeGen.vmRegisters.nextFree()
+        code += exprGen.translateExpression(call.args[0], leftRegister, -1)
+        code += exprGen.translateExpression(call.args[1], rightRegister, -1)
+        code += VmCodeInstruction(Opcode.CMP, codeGen.vmType(call.args[0].type), reg1=leftRegister, reg2=rightRegister)
+        return code
+    }
+
+    private fun funcAny(call: PtBuiltinFunctionCall, resultRegister: Int): VmCodeChunk {
+        val arrayName = call.args[0] as PtIdentifier
+        val array = codeGen.symbolTable.flat.getValue(arrayName.targetName) as StStaticVariable
+        val code = VmCodeChunk()
+        val syscall =
+            when (array.dt) {
+                DataType.ARRAY_UB,
+                DataType.ARRAY_B -> Syscall.ANY_BYTE
+                DataType.ARRAY_UW,
+                DataType.ARRAY_W -> Syscall.ANY_WORD
+                DataType.ARRAY_F -> Syscall.ANY_FLOAT
+                else -> throw IllegalArgumentException("weird type")
+            }
+        code += exprGen.translateExpression(call.args[0], 0, -1)
+        code += VmCodeInstruction(Opcode.LOAD, VmDataType.BYTE, reg1 = 1, value = array.length)
+        code += VmCodeInstruction(Opcode.SYSCALL, value = syscall.ordinal)
+        if (resultRegister != 0)
+            code += VmCodeInstruction(Opcode.LOADR, VmDataType.BYTE, reg1 = resultRegister, reg2 = 0)
+        return code
+    }
+
+    private fun funcAll(call: PtBuiltinFunctionCall, resultRegister: Int): VmCodeChunk {
+        val arrayName = call.args[0] as PtIdentifier
+        val array = codeGen.symbolTable.flat.getValue(arrayName.targetName) as StStaticVariable
+        val syscall =
+            when(array.dt) {
+                DataType.ARRAY_UB,
+                DataType.ARRAY_B -> Syscall.ALL_BYTE
+                DataType.ARRAY_UW,
+                DataType.ARRAY_W -> Syscall.ALL_WORD
+                DataType.ARRAY_F -> Syscall.ALL_FLOAT
+                else -> throw IllegalArgumentException("weird type")
+            }
+        val code = VmCodeChunk()
+        code += exprGen.translateExpression(call.args[0], 0, -1)
+        code += VmCodeInstruction(Opcode.LOAD, VmDataType.BYTE, reg1=1, value=array.length)
+        code += VmCodeInstruction(Opcode.SYSCALL, value=syscall.ordinal)
+        if(resultRegister!=0)
+            code += VmCodeInstruction(Opcode.LOADR, VmDataType.BYTE, reg1=resultRegister, reg2=0)
+        return code
+    }
+
+    private fun funcAbs(call: PtBuiltinFunctionCall, resultRegister: Int): VmCodeChunk {
+        val code = VmCodeChunk()
+        val sourceDt = call.args.single().type
+        if(sourceDt!=DataType.UWORD) {
+            code += exprGen.translateExpression(call.args[0], resultRegister, -1)
+            when (sourceDt) {
+                DataType.UBYTE -> {
+                    code += VmCodeInstruction(Opcode.EXT, VmDataType.BYTE, reg1=resultRegister)
+                }
+                DataType.BYTE -> {
+                    val andReg = codeGen.vmRegisters.nextFree()
+                    val notNegativeLabel = codeGen.createLabelName()
+                    code += VmCodeInstruction(Opcode.LOAD, VmDataType.BYTE, reg1=andReg, value=0x80)
+                    code += VmCodeInstruction(Opcode.AND, VmDataType.BYTE, reg1=andReg, reg2=resultRegister)
+                    code += VmCodeInstruction(Opcode.BZ, VmDataType.BYTE, reg1=andReg, labelSymbol = notNegativeLabel)
+                    code += VmCodeInstruction(Opcode.NEG, VmDataType.BYTE, reg1=resultRegister)
+                    code += VmCodeInstruction(Opcode.EXT, VmDataType.BYTE, reg1=resultRegister)
+                    code += VmCodeLabel(notNegativeLabel)
+                }
+                DataType.WORD -> {
+                    val andReg = codeGen.vmRegisters.nextFree()
+                    val notNegativeLabel = codeGen.createLabelName()
+                    code += VmCodeInstruction(Opcode.LOAD, VmDataType.WORD, reg1=andReg, value=0x8000)
+                    code += VmCodeInstruction(Opcode.AND, VmDataType.WORD, reg1=andReg, reg2=resultRegister)
+                    code += VmCodeInstruction(Opcode.BZ, VmDataType.WORD, reg1=andReg, labelSymbol = notNegativeLabel)
+                    code += VmCodeInstruction(Opcode.NEG, VmDataType.WORD, reg1=resultRegister)
+                    code += VmCodeLabel(notNegativeLabel)
+                }
+                else -> throw AssemblyError("weird type")
+            }
+        }
+        return code
+    }
+
+    private fun funcSgn(call: PtBuiltinFunctionCall, resultRegister: Int): VmCodeChunk {
+        val code = VmCodeChunk()
+        val reg = codeGen.vmRegisters.nextFree()
+        code += exprGen.translateExpression(call.args.single(), reg, -1)
+        code += VmCodeInstruction(Opcode.SGN, codeGen.vmType(call.type), reg1=resultRegister, reg2=reg)
+        return code
+    }
+
+    private fun funcSqrt16(call: PtBuiltinFunctionCall, resultRegister: Int): VmCodeChunk {
+        val code = VmCodeChunk()
+        val reg = codeGen.vmRegisters.nextFree()
+        code += exprGen.translateExpression(call.args.single(), reg, -1)
+        code += VmCodeInstruction(Opcode.SQRT, VmDataType.WORD, reg1=resultRegister, reg2=reg)
+        return code
+    }
+
+    private fun funcPop(call: PtBuiltinFunctionCall): VmCodeChunk {
+        val code = VmCodeChunk()
+        val reg = codeGen.vmRegisters.nextFree()
+        code += VmCodeInstruction(Opcode.POP, VmDataType.BYTE, reg1=reg)
+        code += assignRegisterTo(call.args.single(), reg)
+        return code
+    }
+
+    private fun funcPopw(call: PtBuiltinFunctionCall): VmCodeChunk {
+        val code = VmCodeChunk()
+        val reg = codeGen.vmRegisters.nextFree()
+        code += VmCodeInstruction(Opcode.POP, VmDataType.WORD, reg1=reg)
+        code += assignRegisterTo(call.args.single(), reg)
+        return code
+    }
+
+    private fun funcPush(call: PtBuiltinFunctionCall): VmCodeChunk {
+        val code = VmCodeChunk()
+        val reg = codeGen.vmRegisters.nextFree()
+        code += exprGen.translateExpression(call.args.single(), reg, -1)
+        code += VmCodeInstruction(Opcode.PUSH, VmDataType.BYTE, reg1=reg)
+        return code
+    }
+
+    private fun funcPushw(call: PtBuiltinFunctionCall): VmCodeChunk {
+        val code = VmCodeChunk()
+        val reg = codeGen.vmRegisters.nextFree()
+        code += exprGen.translateExpression(call.args.single(), reg, -1)
+        code += VmCodeInstruction(Opcode.PUSH, VmDataType.WORD, reg1=reg)
+        return code
+    }
+
+    private fun funcSwap(call: PtBuiltinFunctionCall): VmCodeChunk {
+        val left = call.args[0]
+        val right = call.args[1]
+        val leftReg = codeGen.vmRegisters.nextFree()
+        val rightReg = codeGen.vmRegisters.nextFree()
+        val code = VmCodeChunk()
+        code += exprGen.translateExpression(left, leftReg, -1)
+        code += exprGen.translateExpression(right, rightReg, -1)
+        code += assignRegisterTo(left, rightReg)
+        code += assignRegisterTo(right, leftReg)
+        return code
+    }
+
+    private fun funcReverse(call: PtBuiltinFunctionCall): VmCodeChunk {
+        val arrayName = call.args[0] as PtIdentifier
+        val array = codeGen.symbolTable.flat.getValue(arrayName.targetName) as StStaticVariable
+        val sortSyscall =
+            when(array.dt) {
+                DataType.ARRAY_UB, DataType.ARRAY_B, DataType.STR -> Syscall.REVERSE_BYTES
+                DataType.ARRAY_UW, DataType.ARRAY_W -> Syscall.REVERSE_WORDS
+                DataType.ARRAY_F -> Syscall.REVERSE_FLOATS
+                else -> throw IllegalArgumentException("weird type to reverse")
+            }
+        val code = VmCodeChunk()
+        code += exprGen.translateExpression(call.args[0], 0, -1)
+        code += VmCodeInstruction(Opcode.LOAD, VmDataType.BYTE, reg1=1, value=array.length)
+        code += VmCodeInstruction(Opcode.SYSCALL, value=sortSyscall.ordinal)
+        return code
+    }
+
+    private fun funcSort(call: PtBuiltinFunctionCall): VmCodeChunk {
+        val arrayName = call.args[0] as PtIdentifier
+        val array = codeGen.symbolTable.flat.getValue(arrayName.targetName) as StStaticVariable
+        val sortSyscall =
+            when(array.dt) {
+                DataType.ARRAY_UB -> Syscall.SORT_UBYTE
+                DataType.ARRAY_B -> Syscall.SORT_BYTE
+                DataType.ARRAY_UW -> Syscall.SORT_UWORD
+                DataType.ARRAY_W -> Syscall.SORT_WORD
+                DataType.STR -> Syscall.SORT_UBYTE
+                DataType.ARRAY_F -> throw java.lang.IllegalArgumentException("sorting a floating point array is not supported")
+                else -> throw IllegalArgumentException("weird type to sort")
+            }
+        val code = VmCodeChunk()
+        code += exprGen.translateExpression(call.args[0], 0, -1)
+        code += VmCodeInstruction(Opcode.LOAD, VmDataType.BYTE, reg1=1, value=array.length)
+        code += VmCodeInstruction(Opcode.SYSCALL, value=sortSyscall.ordinal)
+        return code
+    }
+
+    private fun funcMkword(call: PtBuiltinFunctionCall, resultRegister: Int): VmCodeChunk {
+        val msbReg = codeGen.vmRegisters.nextFree()
+        val code = VmCodeChunk()
+        code += exprGen.translateExpression(call.args[0], msbReg, -1)
+        code += exprGen.translateExpression(call.args[1], resultRegister, -1)
+        code += VmCodeInstruction(Opcode.CONCAT, VmDataType.BYTE, reg1=resultRegister, reg2=msbReg)
+        return code
+    }
+
+    private fun funcPokeW(call: PtBuiltinFunctionCall): VmCodeChunk {
+        val code = VmCodeChunk()
+        if(codeGen.isZero(call.args[1])) {
+            if (call.args[0] is PtNumber) {
+                val address = (call.args[0] as PtNumber).number.toInt()
+                code += VmCodeInstruction(Opcode.STOREZM, VmDataType.WORD, value = address)
+            } else {
+                val addressReg = codeGen.vmRegisters.nextFree()
+                code += exprGen.translateExpression(call.args[0], addressReg, -1)
+                code += VmCodeInstruction(Opcode.STOREZI, VmDataType.WORD, reg2 = addressReg)
+            }
+        } else {
+            val valueReg = codeGen.vmRegisters.nextFree()
+            if (call.args[0] is PtNumber) {
+                val address = (call.args[0] as PtNumber).number.toInt()
+                code += exprGen.translateExpression(call.args[1], valueReg, -1)
+                code += VmCodeInstruction(Opcode.STOREM, VmDataType.WORD, reg1 = valueReg, value = address)
+            } else {
+                val addressReg = codeGen.vmRegisters.nextFree()
+                code += exprGen.translateExpression(call.args[0], addressReg, -1)
+                code += exprGen.translateExpression(call.args[1], valueReg, -1)
+                code += VmCodeInstruction(Opcode.STOREI, VmDataType.WORD, reg1 = valueReg, reg2 = addressReg)
+            }
+        }
+        return code
+    }
+
+    private fun funcPoke(call: PtBuiltinFunctionCall): VmCodeChunk {
+        val code = VmCodeChunk()
+        if(codeGen.isZero(call.args[1])) {
+            if (call.args[0] is PtNumber) {
+                val address = (call.args[0] as PtNumber).number.toInt()
+                code += VmCodeInstruction(Opcode.STOREZM, VmDataType.BYTE, value = address)
+            } else {
+                val addressReg = codeGen.vmRegisters.nextFree()
+                code += exprGen.translateExpression(call.args[0], addressReg, -1)
+                code += VmCodeInstruction(Opcode.STOREZI, VmDataType.BYTE, reg2 = addressReg)
+            }
+        } else {
+            val valueReg = codeGen.vmRegisters.nextFree()
+            if (call.args[0] is PtNumber) {
+                val address = (call.args[0] as PtNumber).number.toInt()
+                code += exprGen.translateExpression(call.args[1], valueReg, -1)
+                code += VmCodeInstruction(Opcode.STOREM, VmDataType.BYTE, reg1 = valueReg, value = address)
+            } else {
+                val addressReg = codeGen.vmRegisters.nextFree()
+                code += exprGen.translateExpression(call.args[0], addressReg, -1)
+                code += exprGen.translateExpression(call.args[1], valueReg, -1)
+                code += VmCodeInstruction(Opcode.STOREI, VmDataType.BYTE, reg1 = valueReg, reg2 = addressReg)
+            }
+        }
+        return code
+    }
+
+    private fun funcPeekW(call: PtBuiltinFunctionCall, resultRegister: Int): VmCodeChunk {
+        val code = VmCodeChunk()
+        if(call.args[0] is PtNumber) {
+            val address = (call.args[0] as PtNumber).number.toInt()
+            code += VmCodeInstruction(Opcode.LOADM, VmDataType.WORD, reg1 = resultRegister, value = address)
+        } else {
+            val addressReg = codeGen.vmRegisters.nextFree()
+            code += exprGen.translateExpression(call.args.single(), addressReg, -1)
+            code += VmCodeInstruction(Opcode.LOADI, VmDataType.WORD, reg1 = resultRegister, reg2 = addressReg)
+        }
+        return code
+    }
+
+    private fun funcPeek(call: PtBuiltinFunctionCall, resultRegister: Int): VmCodeChunk {
+        val code = VmCodeChunk()
+        if(call.args[0] is PtNumber) {
+            val address = (call.args[0] as PtNumber).number.toInt()
+            code += VmCodeInstruction(Opcode.LOADM, VmDataType.BYTE, reg1 = resultRegister, value = address)
+        } else {
+            val addressReg = codeGen.vmRegisters.nextFree()
+            code += exprGen.translateExpression(call.args.single(), addressReg, -1)
+            code += VmCodeInstruction(Opcode.LOADI, VmDataType.BYTE, reg1 = resultRegister, reg2 = addressReg)
+        }
+        return code
+    }
+
+    private fun funcRnd(resultRegister: Int): VmCodeChunk {
+        val code = VmCodeChunk()
+        code += VmCodeInstruction(Opcode.RND, VmDataType.BYTE, reg1=resultRegister)
+        return code
+    }
+
+    private fun funcRndw(resultRegister: Int): VmCodeChunk {
+        val code = VmCodeChunk()
+        code += VmCodeInstruction(Opcode.RND, VmDataType.WORD, reg1=resultRegister)
+        return code
+    }
+
+    private fun funcMemory(call: PtBuiltinFunctionCall, resultRegister: Int): VmCodeChunk {
+        val name = (call.args[0] as PtString).value
+        val size = (call.args[1] as PtNumber).number.toUInt()
+        val align = (call.args[2] as PtNumber).number.toUInt()
+        val existing = codeGen.allocations.getMemorySlab(name)
+        val address = if(existing==null)
+            codeGen.allocations.allocateMemorySlab(name, size, align)
+        else if(existing.second!=size || existing.third!=align) {
+            codeGen.errors.err("memory slab '$name' already exists with a different size or alignment", call.position)
+            return VmCodeChunk()
+        }
+        else
+            existing.first
+        val code = VmCodeChunk()
+        code += VmCodeInstruction(Opcode.LOAD, VmDataType.WORD, reg1=resultRegister, value=address.toInt())
+        return code
+    }
+
+    private fun funcLsb(call: PtBuiltinFunctionCall, resultRegister: Int): VmCodeChunk {
+        val code = VmCodeChunk()
+        code += exprGen.translateExpression(call.args.single(), resultRegister, -1)
+        // note: if a word result is needed, the upper byte is cleared by the typecast that follows. No need to do it here.
+        return code
+    }
+
+    private fun funcMsb(call: PtBuiltinFunctionCall, resultRegister: Int): VmCodeChunk {
+        val code = VmCodeChunk()
+        code += exprGen.translateExpression(call.args.single(), resultRegister, -1)
+        code += VmCodeInstruction(Opcode.MSIG, VmDataType.BYTE, reg1 = resultRegister, reg2=resultRegister)
+        // note: if a word result is needed, the upper byte is cleared by the typecast that follows. No need to do it here.
+        return code
+    }
+
+    private fun funcRolRor2(opcode: Opcode, call: PtBuiltinFunctionCall, resultRegister: Int): VmCodeChunk {
+        val vmDt = codeGen.vmType(call.args[0].type)
+        val code = VmCodeChunk()
+        code += exprGen.translateExpression(call.args[0], resultRegister, -1)
+        code += VmCodeInstruction(opcode, vmDt, reg1=resultRegister)
+        code += assignRegisterTo(call.args[0], resultRegister)
+        return code
+    }
+
+    private fun assignRegisterTo(target: PtExpression, register: Int): VmCodeChunk {
+        val code = VmCodeChunk()
+        val assignment = PtAssignment(target.position)
+        val assignTarget = PtAssignTarget(target.position)
+        assignTarget.children.add(target)
+        assignment.children.add(assignTarget)
+        assignment.children.add(PtMachineRegister(register, target.type, target.position))
+        code += codeGen.translateNode(assignment)
+        return code
+    }
+}

codeGenVirtual/src/prog8/codegen/virtual/CodeGen.kt

@@ -0,0 +1,832 @@
+package prog8.codegen.virtual
+
+import prog8.code.StStaticVariable
+import prog8.code.SymbolTable
+import prog8.code.ast.*
+import prog8.code.core.*
+import prog8.vm.Opcode
+import prog8.vm.VmDataType
+import kotlin.math.pow
+
+
+internal class VmRegisterPool {
+    private var firstFree: Int=3        // integer registers 0,1,2 are reserved
+    private var firstFreeFloat: Int=0
+
+    fun peekNext() = firstFree
+    fun peekNextFloat() = firstFreeFloat
+
+    fun nextFree(): Int {
+        val result = firstFree
+        firstFree++
+        if(firstFree>65535)
+            throw AssemblyError("out of virtual registers (int)")
+        return result
+    }
+
+    fun nextFreeFloat(): Int {
+        val result = firstFreeFloat
+        firstFreeFloat++
+        if(firstFreeFloat>65535)
+            throw AssemblyError("out of virtual registers (fp)")
+        return result
+    }
+}
+
+
+class CodeGen(internal val program: PtProgram,
+              internal val symbolTable: SymbolTable,
+              internal val options: CompilationOptions,
+              internal val errors: IErrorReporter
+): IAssemblyGenerator {
+
+    internal val allocations = VariableAllocator(symbolTable, program, errors)
+    private val expressionEval = ExpressionGen(this)
+    private val builtinFuncGen = BuiltinFuncGen(this, expressionEval)
+    private val assignmentGen = AssignmentGen(this, expressionEval)
+    internal val vmRegisters = VmRegisterPool()
+
+    override fun compileToAssembly(): IAssemblyProgram? {
+        val vmprog = AssemblyProgram(program.name, allocations)
+
+        if(!options.dontReinitGlobals) {
+            // collect global variables initializers
+            program.allBlocks().forEach {
+                val code = VmCodeChunk()
+                it.children.filterIsInstance<PtAssignment>().forEach { assign -> code += assignmentGen.translate(assign) }
+                vmprog.addGlobalInits(code)
+            }
+        }
+
+        for (block in program.allBlocks()) {
+            vmprog.addBlock(translate(block))
+        }
+
+        println("Vm codegen: amount of vm registers=${vmRegisters.peekNext()}")
+
+        return vmprog
+    }
+
+
+    internal fun translateNode(node: PtNode): VmCodeChunk {
+        val code = when(node) {
+            is PtBlock -> translate(node)
+            is PtSub -> translate(node)
+            is PtScopeVarsDecls -> VmCodeChunk() // vars should be looked up via symbol table
+            is PtVariable -> VmCodeChunk() // var should be looked up via symbol table
+            is PtMemMapped -> VmCodeChunk() // memmapped var should be looked up via symbol table
+            is PtConstant -> VmCodeChunk() // constants have all been folded into the code
+            is PtAssignment -> assignmentGen.translate(node)
+            is PtNodeGroup -> translateGroup(node.children)
+            is PtBuiltinFunctionCall -> translateBuiltinFunc(node, 0)
+            is PtFunctionCall -> expressionEval.translate(node, 0, 0)
+            is PtNop -> VmCodeChunk()
+            is PtReturn -> translate(node)
+            is PtJump -> translate(node)
+            is PtWhen -> translate(node)
+            is PtPipe -> expressionEval.translate(node, 0)
+            is PtForLoop -> translate(node)
+            is PtIfElse -> translate(node)
+            is PtPostIncrDecr -> translate(node)
+            is PtRepeatLoop -> translate(node)
+            is PtLabel -> VmCodeChunk(VmCodeLabel(node.scopedName))
+            is PtBreakpoint -> VmCodeChunk(VmCodeInstruction(Opcode.BREAKPOINT))
+            is PtConditionalBranch -> translate(node)
+            is PtInlineAssembly -> VmCodeChunk(VmCodeInlineAsm(node.assembly))
+            is PtIncludeBinary -> VmCodeChunk(VmCodeInlineBinary(node.file, node.offset, node.length))
+            is PtAsmSub -> TODO("asmsub not yet supported on virtual machine target ${node.position}")
+            is PtAddressOf,
+            is PtContainmentCheck,
+            is PtMemoryByte,
+            is PtProgram,
+            is PtArrayIndexer,
+            is PtBinaryExpression,
+            is PtIdentifier,
+            is PtWhenChoice,
+            is PtPrefix,
+            is PtRange,
+            is PtAssignTarget,
+            is PtTypeCast,
+            is PtSubroutineParameter,
+            is PtNumber,
+            is PtArray,
+            is PtString -> throw AssemblyError("should not occur as separate statement node ${node.position}")
+            else -> TODO("missing codegen for $node")
+        }
+        if(code.lines.isNotEmpty() && node.position.line!=0)
+            code.lines.add(0, VmCodeComment(node.position.toString()))
+        return code
+    }
+
+    private fun translate(branch: PtConditionalBranch): VmCodeChunk {
+        val code = VmCodeChunk()
+        val elseLabel = createLabelName()
+        // note that the branch opcode used is the opposite as the branch condition, because the generated code jumps to the 'else' part
+        code += when(branch.condition) {
+            BranchCondition.CS -> VmCodeInstruction(Opcode.BSTCC, labelSymbol = elseLabel)
+            BranchCondition.CC -> VmCodeInstruction(Opcode.BSTCS, labelSymbol = elseLabel)
+            BranchCondition.EQ, BranchCondition.Z -> VmCodeInstruction(Opcode.BSTNE, labelSymbol = elseLabel)
+            BranchCondition.NE, BranchCondition.NZ -> VmCodeInstruction(Opcode.BSTEQ, labelSymbol = elseLabel)
+            BranchCondition.MI, BranchCondition.NEG -> VmCodeInstruction(Opcode.BSTPOS, labelSymbol = elseLabel)
+            BranchCondition.PL, BranchCondition.POS -> VmCodeInstruction(Opcode.BSTNEG, labelSymbol = elseLabel)
+            BranchCondition.VC,
+            BranchCondition.VS -> throw AssemblyError("conditional branch ${branch.condition} not supported in vm target due to lack of cpu V flag ${branch.position}")
+        }
+        code += translateNode(branch.trueScope)
+        if(branch.falseScope.children.isNotEmpty()) {
+            val endLabel = createLabelName()
+            code += VmCodeInstruction(Opcode.JUMP, labelSymbol = endLabel)
+            code += VmCodeLabel(elseLabel)
+            code += translateNode(branch.falseScope)
+            code += VmCodeLabel(endLabel)
+        } else {
+            code += VmCodeLabel(elseLabel)
+        }
+        return code
+    }
+
+    private fun translate(whenStmt: PtWhen): VmCodeChunk {
+        if(whenStmt.choices.children.isEmpty())
+            return VmCodeChunk()
+        val code = VmCodeChunk()
+        val valueReg = vmRegisters.nextFree()
+        val choiceReg = vmRegisters.nextFree()
+        val valueDt = vmType(whenStmt.value.type)
+        code += expressionEval.translateExpression(whenStmt.value, valueReg, -1)
+        val choices = whenStmt.choices.children.map {it as PtWhenChoice }
+        val endLabel = createLabelName()
+        for (choice in choices) {
+            if(choice.isElse) {
+                code += translateNode(choice.statements)
+            } else {
+                val skipLabel = createLabelName()
+                val values = choice.values.children.map {it as PtNumber}
+                if(values.size==1) {
+                    code += VmCodeInstruction(Opcode.LOAD, valueDt, reg1=choiceReg, value=values[0].number.toInt())
+                    code += VmCodeInstruction(Opcode.BNE, valueDt, reg1=valueReg, reg2=choiceReg, labelSymbol = skipLabel)
+                    code += translateNode(choice.statements)
+                    if(choice.statements.children.last() !is PtReturn)
+                        code += VmCodeInstruction(Opcode.JUMP, labelSymbol = endLabel)
+                } else {
+                    val matchLabel = createLabelName()
+                    for (value in values) {
+                        code += VmCodeInstruction(Opcode.LOAD, valueDt, reg1=choiceReg, value=value.number.toInt())
+                        code += VmCodeInstruction(Opcode.BEQ, valueDt, reg1=valueReg, reg2=choiceReg, labelSymbol = matchLabel)
+                    }
+                    code += VmCodeInstruction(Opcode.JUMP, labelSymbol = skipLabel)
+                    code += VmCodeLabel(matchLabel)
+                    code += translateNode(choice.statements)
+                    if(choice.statements.children.last() !is PtReturn)
+                        code += VmCodeInstruction(Opcode.JUMP, labelSymbol = endLabel)
+                }
+                code += VmCodeLabel(skipLabel)
+            }
+        }
+        code += VmCodeLabel(endLabel)
+        return code
+    }
+
+    private fun translate(forLoop: PtForLoop): VmCodeChunk {
+        val loopvar = symbolTable.lookup(forLoop.variable.targetName) as StStaticVariable
+        val iterable = forLoop.iterable
+        val code = VmCodeChunk()
+        when(iterable) {
+            is PtRange -> {
+                if(iterable.from is PtNumber && iterable.to is PtNumber)
+                    code += translateForInConstantRange(forLoop, loopvar)
+                else
+                    code += translateForInNonConstantRange(forLoop, loopvar)
+            }
+            is PtIdentifier -> {
+                val arrayAddress = allocations.get(iterable.targetName)
+                val iterableVar = symbolTable.lookup(iterable.targetName) as StStaticVariable
+                val loopvarAddress = allocations.get(loopvar.scopedName)
+                val indexReg = vmRegisters.nextFree()
+                val tmpReg = vmRegisters.nextFree()
+                val loopLabel = createLabelName()
+                val endLabel = createLabelName()
+                if(iterableVar.dt==DataType.STR) {
+                    // iterate over a zero-terminated string
+                    code += VmCodeInstruction(Opcode.LOAD, VmDataType.BYTE, reg1=indexReg, value=0)
+                    code += VmCodeLabel(loopLabel)
+                    code += VmCodeInstruction(Opcode.LOADX, VmDataType.BYTE, reg1=tmpReg, reg2=indexReg, value = arrayAddress)
+                    code += VmCodeInstruction(Opcode.BZ, VmDataType.BYTE, reg1=tmpReg, labelSymbol = endLabel)
+                    code += VmCodeInstruction(Opcode.STOREM, VmDataType.BYTE, reg1=tmpReg, value = loopvarAddress)
+                    code += translateNode(forLoop.statements)
+                    code += VmCodeInstruction(Opcode.INC, VmDataType.BYTE, reg1=indexReg)
+                    code += VmCodeInstruction(Opcode.JUMP, labelSymbol = loopLabel)
+                    code += VmCodeLabel(endLabel)
+                } else {
+                    // iterate over array
+                    val elementDt = ArrayToElementTypes.getValue(iterable.type)
+                    val elementSize = program.memsizer.memorySize(elementDt)
+                    val lengthBytes = iterableVar.length!! * elementSize
+                    if(lengthBytes<256) {
+                        val lengthReg = vmRegisters.nextFree()
+                        code += VmCodeInstruction(Opcode.LOAD, VmDataType.BYTE, reg1=indexReg, value=0)
+                        code += VmCodeInstruction(Opcode.LOAD, VmDataType.BYTE, reg1=lengthReg, value=lengthBytes)
+                        code += VmCodeLabel(loopLabel)
+                        code += VmCodeInstruction(Opcode.LOADX, vmType(elementDt), reg1=tmpReg, reg2=indexReg, value=arrayAddress)
+                        code += VmCodeInstruction(Opcode.STOREM, vmType(elementDt), reg1=tmpReg, value = loopvarAddress)
+                        code += translateNode(forLoop.statements)
+                        code += addConstReg(VmDataType.BYTE, indexReg, elementSize)
+                        code += VmCodeInstruction(Opcode.BNE, VmDataType.BYTE, reg1=indexReg, reg2=lengthReg, labelSymbol = loopLabel)
+                    } else if(lengthBytes==256) {
+                        code += VmCodeInstruction(Opcode.LOAD, VmDataType.BYTE, reg1=indexReg, value=0)
+                        code += VmCodeLabel(loopLabel)
+                        code += VmCodeInstruction(Opcode.LOADX, vmType(elementDt), reg1=tmpReg, reg2=indexReg, value=arrayAddress)
+                        code += VmCodeInstruction(Opcode.STOREM, vmType(elementDt), reg1=tmpReg, value = loopvarAddress)
+                        code += translateNode(forLoop.statements)
+                        code += addConstReg(VmDataType.BYTE, indexReg, elementSize)
+                        code += VmCodeInstruction(Opcode.BNZ, VmDataType.BYTE, reg1=indexReg, labelSymbol = loopLabel)
+                    } else {
+                        throw AssemblyError("iterator length should never exceed 256")
+                    }
+                }
+            }
+            else -> throw AssemblyError("weird for iterable")
+        }
+        return code
+    }
+
+    private fun translateForInNonConstantRange(forLoop: PtForLoop, loopvar: StStaticVariable): VmCodeChunk {
+        val iterable = forLoop.iterable as PtRange
+        val step = iterable.step.number.toInt()
+        if (step==0)
+            throw AssemblyError("step 0")
+        val indexReg = vmRegisters.nextFree()
+        val endvalueReg = vmRegisters.nextFree()
+        val loopvarAddress = allocations.get(loopvar.scopedName)
+        val loopvarDt = vmType(loopvar.dt)
+        val loopLabel = createLabelName()
+        val code = VmCodeChunk()
+
+        code += expressionEval.translateExpression(iterable.to, endvalueReg, -1)
+        code += expressionEval.translateExpression(iterable.from, indexReg, -1)
+        code += VmCodeInstruction(Opcode.STOREM, loopvarDt, reg1=indexReg, value=loopvarAddress)
+        code += VmCodeLabel(loopLabel)
+        code += translateNode(forLoop.statements)
+        if(step<3) {
+            code += addConstMem(loopvarDt, loopvarAddress.toUInt(), step)
+            code += VmCodeInstruction(Opcode.LOADM, loopvarDt, reg1 = indexReg, value = loopvarAddress)
+        } else {
+            code += VmCodeInstruction(Opcode.LOADM, loopvarDt, reg1 = indexReg, value = loopvarAddress)
+            code += addConstReg(loopvarDt, indexReg, step)
+            code += VmCodeInstruction(Opcode.STOREM, loopvarDt, reg1 = indexReg, value = loopvarAddress)
+        }
+        val branchOpcode = if(loopvar.dt in SignedDatatypes) Opcode.BLES else Opcode.BLE
+        code += VmCodeInstruction(branchOpcode, loopvarDt, reg1=indexReg, reg2=endvalueReg, labelSymbol=loopLabel)
+        return code
+    }
+
+    private fun translateForInConstantRange(forLoop: PtForLoop, loopvar: StStaticVariable): VmCodeChunk {
+        val loopLabel = createLabelName()
+        val loopvarAddress = allocations.get(loopvar.scopedName)
+        val indexReg = vmRegisters.nextFree()
+        val loopvarDt = vmType(loopvar.dt)
+        val iterable = forLoop.iterable as PtRange
+        val step = iterable.step.number.toInt()
+        val rangeStart = (iterable.from as PtNumber).number.toInt()
+        val rangeEndUntyped = (iterable.to as PtNumber).number.toInt() + step
+        if(step==0)
+            throw AssemblyError("step 0")
+        if(step>0 && rangeEndUntyped<rangeStart || step<0 && rangeEndUntyped>rangeStart)
+            throw AssemblyError("empty range")
+        val rangeEndWrapped = if(loopvarDt==VmDataType.BYTE) rangeEndUntyped and 255 else rangeEndUntyped and 65535
+        val code = VmCodeChunk()
+        val endvalueReg: Int
+        if(rangeEndWrapped!=0) {
+            endvalueReg = vmRegisters.nextFree()
+            code += VmCodeInstruction(Opcode.LOAD, loopvarDt, reg1 = endvalueReg, value = rangeEndWrapped)
+        } else {
+            endvalueReg = -1 // not used
+        }
+        code += VmCodeInstruction(Opcode.LOAD, loopvarDt, reg1=indexReg, value=rangeStart)
+        code += VmCodeInstruction(Opcode.STOREM, loopvarDt, reg1=indexReg, value=loopvarAddress)
+        code += VmCodeLabel(loopLabel)
+        code += translateNode(forLoop.statements)
+        if(step<3) {
+            code += addConstMem(loopvarDt, loopvarAddress.toUInt(), step)
+            code += VmCodeInstruction(Opcode.LOADM, loopvarDt, reg1 = indexReg, value = loopvarAddress)
+        } else {
+            code += VmCodeInstruction(Opcode.LOADM, loopvarDt, reg1 = indexReg, value = loopvarAddress)
+            code += addConstReg(loopvarDt, indexReg, step)
+            code += VmCodeInstruction(Opcode.STOREM, loopvarDt, reg1 = indexReg, value = loopvarAddress)
+        }
+        code += if(rangeEndWrapped==0) {
+            VmCodeInstruction(Opcode.BNZ, loopvarDt, reg1 = indexReg, labelSymbol = loopLabel)
+        } else {
+            VmCodeInstruction(Opcode.BNE, loopvarDt, reg1 = indexReg, reg2 = endvalueReg, labelSymbol = loopLabel)
+        }
+        return code
+    }
+
+    private fun addConstReg(dt: VmDataType, reg: Int, value: Int): VmCodeChunk {
+        val code = VmCodeChunk()
+        when(value) {
+            0 -> { /* do nothing */ }
+            1 -> {
+                code += VmCodeInstruction(Opcode.INC, dt, reg1=reg)
+            }
+            2 -> {
+                code += VmCodeInstruction(Opcode.INC, dt, reg1=reg)
+                code += VmCodeInstruction(Opcode.INC, dt, reg1=reg)
+            }
+            -1 -> {
+                code += VmCodeInstruction(Opcode.DEC, dt, reg1=reg)
+            }
+            -2 -> {
+                code += VmCodeInstruction(Opcode.DEC, dt, reg1=reg)
+                code += VmCodeInstruction(Opcode.DEC, dt, reg1=reg)
+            }
+            else -> {
+                val valueReg = vmRegisters.nextFree()
+                if(value>0) {
+                    code += VmCodeInstruction(Opcode.LOAD, dt, reg1=valueReg, value= value)
+                    code += VmCodeInstruction(Opcode.ADD, dt, reg1 = reg, reg2 = valueReg)
+                }
+                else {
+                    code += VmCodeInstruction(Opcode.LOAD, dt, reg1=valueReg, value= -value)
+                    code += VmCodeInstruction(Opcode.SUB, dt, reg1 = reg, reg2 = valueReg)
+                }
+            }
+        }
+        return code
+    }
+
+    private fun addConstMem(dt: VmDataType, address: UInt, value: Int): VmCodeChunk {
+        val code = VmCodeChunk()
+        when(value) {
+            0 -> { /* do nothing */ }
+            1 -> {
+                code += VmCodeInstruction(Opcode.INCM, dt, value=address.toInt())
+            }
+            2 -> {
+                code += VmCodeInstruction(Opcode.INCM, dt, value=address.toInt())
+                code += VmCodeInstruction(Opcode.INCM, dt, value=address.toInt())
+            }
+            -1 -> {
+                code += VmCodeInstruction(Opcode.DECM, dt, value=address.toInt())
+            }
+            -2 -> {
+                code += VmCodeInstruction(Opcode.DECM, dt, value=address.toInt())
+                code += VmCodeInstruction(Opcode.DECM, dt, value=address.toInt())
+            }
+            else -> {
+                val valueReg = vmRegisters.nextFree()
+                val operandReg = vmRegisters.nextFree()
+                if(value>0) {
+                    code += VmCodeInstruction(Opcode.LOADM, dt, reg1=valueReg, value=address.toInt())
+                    code += VmCodeInstruction(Opcode.LOAD, dt, reg1=operandReg, value=value)
+                    code += VmCodeInstruction(Opcode.ADD, dt, reg1 = valueReg, reg2 = operandReg)
+                    code += VmCodeInstruction(Opcode.STOREM, dt, reg1=valueReg, value=address.toInt())
+                }
+                else {
+                    code += VmCodeInstruction(Opcode.LOADM, dt, reg1=valueReg, value=address.toInt())
+                    code += VmCodeInstruction(Opcode.LOAD, dt, reg1=operandReg, value=-value)
+                    code += VmCodeInstruction(Opcode.SUB, dt, reg1 = valueReg, reg2 = operandReg)
+                    code += VmCodeInstruction(Opcode.STOREM, dt, reg1=valueReg, value=address.toInt())
+                }
+            }
+        }
+        return code
+    }
+
+    internal fun multiplyByConstFloat(fpReg: Int, factor: Float): VmCodeChunk {
+        val code = VmCodeChunk()
+        if(factor==1f)
+            return code
+        if(factor==0f) {
+            code += VmCodeInstruction(Opcode.LOAD, VmDataType.FLOAT, fpReg1 = fpReg, fpValue = 0f)
+        } else {
+            val factorReg = vmRegisters.nextFreeFloat()
+            code += VmCodeInstruction(Opcode.LOAD, VmDataType.FLOAT, fpReg1=factorReg, fpValue = factor)
+            code += VmCodeInstruction(Opcode.MUL, VmDataType.FLOAT, fpReg1 = fpReg, fpReg2 = factorReg)
+        }
+        return code
+    }
+
+    internal fun multiplyByConstFloatInplace(address: Int, factor: Float): VmCodeChunk {
+        val code = VmCodeChunk()
+        if(factor==1f)
+            return code
+        if(factor==0f) {
+            code += VmCodeInstruction(Opcode.STOREZM, VmDataType.FLOAT, value = address)
+        } else {
+            val factorReg = vmRegisters.nextFreeFloat()
+            code += VmCodeInstruction(Opcode.LOAD, VmDataType.FLOAT, fpReg1=factorReg, fpValue = factor)
+            code += VmCodeInstruction(Opcode.MULM, VmDataType.FLOAT, fpReg1 = factorReg, value = address)
+        }
+        return code
+    }
+
+    internal val powersOfTwo = (0..16).map { 2.0.pow(it.toDouble()).toInt() }
+
+    internal fun multiplyByConst(dt: VmDataType, reg: Int, factor: Int): VmCodeChunk {
+        val code = VmCodeChunk()
+        if(factor==1)
+            return code
+        val pow2 = powersOfTwo.indexOf(factor)
+        if(pow2==1) {
+            // just shift 1 bit
+            code += VmCodeInstruction(Opcode.LSL, dt, reg1=reg)
+        }
+        else if(pow2>=1) {
+            // just shift multiple bits
+            val pow2reg = vmRegisters.nextFree()
+            code += VmCodeInstruction(Opcode.LOAD, dt, reg1=pow2reg, value=pow2)
+            code += VmCodeInstruction(Opcode.LSLN, dt, reg1=reg, reg2=pow2reg)
+        } else {
+            if (factor == 0) {
+                code += VmCodeInstruction(Opcode.LOAD, dt, reg1=reg, value=0)
+            }
+            else {
+                val factorReg = vmRegisters.nextFree()
+                code += VmCodeInstruction(Opcode.LOAD, dt, reg1=factorReg, value= factor)
+                code += VmCodeInstruction(Opcode.MUL, dt, reg1=reg, reg2=factorReg)
+            }
+        }
+        return code
+    }
+
+    internal fun multiplyByConstInplace(dt: VmDataType, address: Int, factor: Int): VmCodeChunk {
+        val code = VmCodeChunk()
+        if(factor==1)
+            return code
+        val pow2 = powersOfTwo.indexOf(factor)
+        if(pow2==1) {
+            // just shift 1 bit
+            code += VmCodeInstruction(Opcode.LSLM, dt, value = address)
+        }
+        else if(pow2>=1) {
+            // just shift multiple bits
+            val pow2reg = vmRegisters.nextFree()
+            code += VmCodeInstruction(Opcode.LOAD, dt, reg1=pow2reg, value=pow2)
+            code += VmCodeInstruction(Opcode.LSLNM, dt, reg1=pow2reg, value=address)
+        } else {
+            if (factor == 0) {
+                code += VmCodeInstruction(Opcode.STOREZM, dt, value=address)
+            }
+            else {
+                val factorReg = vmRegisters.nextFree()
+                code += VmCodeInstruction(Opcode.LOAD, dt, reg1=factorReg, value = factor)
+                code += VmCodeInstruction(Opcode.MULM, dt, reg1=factorReg, value = address)
+            }
+        }
+        return code
+    }
+
+    internal fun divideByConstFloat(fpReg: Int, factor: Float): VmCodeChunk {
+        val code = VmCodeChunk()
+        if(factor==1f)
+            return code
+        if(factor==0f) {
+            code += VmCodeInstruction(Opcode.LOAD, VmDataType.FLOAT, fpReg1 = fpReg, fpValue = Float.MAX_VALUE)
+        } else {
+            val factorReg = vmRegisters.nextFreeFloat()
+            code += VmCodeInstruction(Opcode.LOAD, VmDataType.FLOAT, fpReg1=factorReg, fpValue = factor)
+            code += VmCodeInstruction(Opcode.DIVS, VmDataType.FLOAT, fpReg1 = fpReg, fpReg2 = factorReg)
+        }
+        return code
+    }
+
+    internal fun divideByConstFloatInplace(address: Int, factor: Float): VmCodeChunk {
+        val code = VmCodeChunk()
+        if(factor==1f)
+            return code
+        if(factor==0f) {
+            val maxvalueReg = vmRegisters.nextFreeFloat()
+            code += VmCodeInstruction(Opcode.LOAD, VmDataType.FLOAT, fpReg1 = maxvalueReg, fpValue = Float.MAX_VALUE)
+            code += VmCodeInstruction(Opcode.STOREM, VmDataType.FLOAT, fpReg1 = maxvalueReg, value=address)
+        } else {
+            val factorReg = vmRegisters.nextFreeFloat()
+            code += VmCodeInstruction(Opcode.LOAD, VmDataType.FLOAT, fpReg1=factorReg, fpValue = factor)
+            code += VmCodeInstruction(Opcode.DIVSM, VmDataType.FLOAT, fpReg1 = factorReg, value=address)
+        }
+        return code
+    }
+
+    internal fun divideByConst(dt: VmDataType, reg: Int, factor: Int, signed: Boolean): VmCodeChunk {
+        val code = VmCodeChunk()
+        if(factor==1)
+            return code
+        val pow2 = powersOfTwo.indexOf(factor)
+        if(pow2==1) {
+            // just shift 1 bit
+            code += if(signed)
+                VmCodeInstruction(Opcode.ASR, dt, reg1=reg)
+            else
+                VmCodeInstruction(Opcode.LSR, dt, reg1=reg)
+        }
+        else if(pow2>=1) {
+            // just shift multiple bits
+            val pow2reg = vmRegisters.nextFree()
+            code += VmCodeInstruction(Opcode.LOAD, dt, reg1=pow2reg, value=pow2)
+            code += if(signed)
+                VmCodeInstruction(Opcode.ASRN, dt, reg1=reg, reg2=pow2reg)
+            else
+                VmCodeInstruction(Opcode.LSRN, dt, reg1=reg, reg2=pow2reg)
+        } else {
+            if (factor == 0) {
+                code += VmCodeInstruction(Opcode.LOAD, dt, reg1=reg, value=0xffff)
+            }
+            else {
+                val factorReg = vmRegisters.nextFree()
+                code += VmCodeInstruction(Opcode.LOAD, dt, reg1=factorReg, value= factor)
+                code += if(signed)
+                    VmCodeInstruction(Opcode.DIVS, dt, reg1=reg, reg2=factorReg)
+                else
+                    VmCodeInstruction(Opcode.DIV, dt, reg1=reg, reg2=factorReg)
+            }
+        }
+        return code
+    }
+
+    internal fun divideByConstInplace(dt: VmDataType, address: Int, factor: Int, signed: Boolean): VmCodeChunk {
+        val code = VmCodeChunk()
+        if(factor==1)
+            return code
+        val pow2 = powersOfTwo.indexOf(factor)
+        if(pow2==1) {
+            // just shift 1 bit
+            code += if(signed)
+                VmCodeInstruction(Opcode.ASRM, dt, value=address)
+            else
+                VmCodeInstruction(Opcode.LSRM, dt, value=address)
+        }
+        else if(pow2>=1) {
+            // just shift multiple bits
+            val pow2reg = vmRegisters.nextFree()
+            code += VmCodeInstruction(Opcode.LOAD, dt, reg1=pow2reg, value=pow2)
+            code += if(signed)
+                VmCodeInstruction(Opcode.ASRNM, dt, reg1=pow2reg, value=address)
+            else
+                VmCodeInstruction(Opcode.LSRNM, dt, reg1=pow2reg, value=address)
+        } else {
+            if (factor == 0) {
+                val reg = vmRegisters.nextFree()
+                code += VmCodeInstruction(Opcode.LOAD, dt, reg1=reg, value=0xffff)
+                code += VmCodeInstruction(Opcode.STOREM, dt, reg1=reg, value=address)
+            }
+            else {
+                val factorReg = vmRegisters.nextFree()
+                code += VmCodeInstruction(Opcode.LOAD, dt, reg1=factorReg, value= factor)
+                code += if(signed)
+                    VmCodeInstruction(Opcode.DIVSM, dt, reg1=factorReg, value=address)
+                else
+                    VmCodeInstruction(Opcode.DIVM, dt, reg1=factorReg, value=address)
+            }
+        }
+        return code
+    }
+
+    private fun translate(ifElse: PtIfElse): VmCodeChunk {
+        if(ifElse.condition.operator !in ComparisonOperators)
+            throw AssemblyError("if condition should only be a binary comparison expression")
+
+        val signed = ifElse.condition.left.type in arrayOf(DataType.BYTE, DataType.WORD, DataType.FLOAT)
+        val vmDt = vmType(ifElse.condition.left.type)
+        val code = VmCodeChunk()
+
+        fun translateNonZeroComparison(): VmCodeChunk {
+            val elseBranch = when(ifElse.condition.operator) {
+                "==" -> Opcode.BNE
+                "!=" -> Opcode.BEQ
+                "<" -> if(signed) Opcode.BGES else Opcode.BGE
+                ">" -> if(signed) Opcode.BLES else Opcode.BLE
+                "<=" -> if(signed) Opcode.BGTS else Opcode.BGT
+                ">=" -> if(signed) Opcode.BLTS else Opcode.BLT
+                else -> throw AssemblyError("invalid comparison operator")
+            }
+
+            val leftReg = vmRegisters.nextFree()
+            val rightReg = vmRegisters.nextFree()
+            code += expressionEval.translateExpression(ifElse.condition.left, leftReg, -1)
+            code += expressionEval.translateExpression(ifElse.condition.right, rightReg, -1)
+            if(ifElse.elseScope.children.isNotEmpty()) {
+                // if and else parts
+                val elseLabel = createLabelName()
+                val afterIfLabel = createLabelName()
+                code += VmCodeInstruction(elseBranch, vmDt, reg1=leftReg, reg2=rightReg, labelSymbol = elseLabel)
+                code += translateNode(ifElse.ifScope)
+                code += VmCodeInstruction(Opcode.JUMP, labelSymbol = afterIfLabel)
+                code += VmCodeLabel(elseLabel)
+                code += translateNode(ifElse.elseScope)
+                code += VmCodeLabel(afterIfLabel)
+            } else {
+                // only if part
+                val afterIfLabel = createLabelName()
+                code += VmCodeInstruction(elseBranch, vmDt, reg1=leftReg, reg2=rightReg, labelSymbol = afterIfLabel)
+                code += translateNode(ifElse.ifScope)
+                code += VmCodeLabel(afterIfLabel)
+            }
+            return code
+        }
+
+        fun translateZeroComparison(): VmCodeChunk {
+            fun equalOrNotEqualZero(elseBranch: Opcode): VmCodeChunk {
+                val leftReg = vmRegisters.nextFree()
+                code += expressionEval.translateExpression(ifElse.condition.left, leftReg, -1)
+                if(ifElse.elseScope.children.isNotEmpty()) {
+                    // if and else parts
+                    val elseLabel = createLabelName()
+                    val afterIfLabel = createLabelName()
+                    code += VmCodeInstruction(elseBranch, vmDt, reg1=leftReg, labelSymbol = elseLabel)
+                    code += translateNode(ifElse.ifScope)
+                    code += VmCodeInstruction(Opcode.JUMP, labelSymbol = afterIfLabel)
+                    code += VmCodeLabel(elseLabel)
+                    code += translateNode(ifElse.elseScope)
+                    code += VmCodeLabel(afterIfLabel)
+                } else {
+                    // only if part
+                    val afterIfLabel = createLabelName()
+                    code += VmCodeInstruction(elseBranch, vmDt, reg1=leftReg, labelSymbol = afterIfLabel)
+                    code += translateNode(ifElse.ifScope)
+                    code += VmCodeLabel(afterIfLabel)
+                }
+                return code
+            }
+
+            return when (ifElse.condition.operator) {
+                "==" -> {
+                    // if X==0 ...   so we just branch on left expr is Not-zero.
+                    equalOrNotEqualZero(Opcode.BNZ)
+                }
+                "!=" -> {
+                    // if X!=0 ...   so we just branch on left expr is Zero.
+                    equalOrNotEqualZero(Opcode.BZ)
+                }
+                else -> {
+                    // another comparison against 0, just use regular codegen for this.
+                    translateNonZeroComparison()
+                }
+            }
+        }
+
+        return if(constValue(ifElse.condition.right)==0.0)
+            translateZeroComparison()
+        else
+            translateNonZeroComparison()
+    }
+
+
+    private fun translate(postIncrDecr: PtPostIncrDecr): VmCodeChunk {
+        val code = VmCodeChunk()
+        val operationMem: Opcode
+        val operationRegister: Opcode
+        when(postIncrDecr.operator) {
+            "++" -> {
+                operationMem = Opcode.INCM
+                operationRegister = Opcode.INC
+            }
+            "--" -> {
+                operationMem = Opcode.DECM
+                operationRegister = Opcode.DEC
+            }
+            else -> throw AssemblyError("weird operator")
+        }
+        val ident = postIncrDecr.target.identifier
+        val memory = postIncrDecr.target.memory
+        val array = postIncrDecr.target.array
+        val vmDt = vmType(postIncrDecr.target.type)
+        if(ident!=null) {
+            val address = allocations.get(ident.targetName)
+            code += VmCodeInstruction(operationMem, vmDt, value = address)
+        } else if(memory!=null) {
+            if(memory.address is PtNumber) {
+                val address = (memory.address as PtNumber).number.toInt()
+                code += VmCodeInstruction(operationMem, vmDt, value = address)
+            } else {
+                val incReg = vmRegisters.nextFree()
+                val addressReg = vmRegisters.nextFree()
+                code += expressionEval.translateExpression(memory.address, addressReg, -1)
+                code += VmCodeInstruction(Opcode.LOADI, vmDt, reg1 = incReg, reg2 = addressReg)
+                code += VmCodeInstruction(operationRegister, vmDt, reg1 = incReg)
+                code += VmCodeInstruction(Opcode.STOREI, vmDt, reg1 = incReg, reg2 = addressReg)
+            }
+        } else if (array!=null) {
+            val variable = array.variable.targetName
+            var variableAddr = allocations.get(variable)
+            val itemsize = program.memsizer.memorySize(array.type)
+            val fixedIndex = constIntValue(array.index)
+            if(fixedIndex!=null) {
+                variableAddr += fixedIndex*itemsize
+                code += VmCodeInstruction(operationMem, vmDt, value=variableAddr)
+            } else {
+                val incReg = vmRegisters.nextFree()
+                val indexReg = vmRegisters.nextFree()
+                code += expressionEval.translateExpression(array.index, indexReg, -1)
+                code += VmCodeInstruction(Opcode.LOADX, vmDt, reg1=incReg, reg2=indexReg, value=variableAddr)
+                code += VmCodeInstruction(operationRegister, vmDt, reg1=incReg)
+                code += VmCodeInstruction(Opcode.STOREX, vmDt, reg1=incReg, reg2=indexReg, value=variableAddr)
+            }
+        } else
+            throw AssemblyError("weird assigntarget")
+
+        return code
+    }
+
+    private fun translate(repeat: PtRepeatLoop): VmCodeChunk {
+        when (constIntValue(repeat.count)) {
+            0 -> return VmCodeChunk()
+            1 -> return translateGroup(repeat.children)
+            256 -> {
+                // 256 iterations can still be done with just a byte counter if you set it to zero as starting value.
+                repeat.children[0] = PtNumber(DataType.UBYTE, 0.0, repeat.count.position)
+            }
+        }
+
+        val code = VmCodeChunk()
+        val counterReg = vmRegisters.nextFree()
+        val vmDt = vmType(repeat.count.type)
+        code += expressionEval.translateExpression(repeat.count, counterReg, -1)
+        val repeatLabel = createLabelName()
+        code += VmCodeLabel(repeatLabel)
+        code += translateNode(repeat.statements)
+        code += VmCodeInstruction(Opcode.DEC, vmDt, reg1=counterReg)
+        code += VmCodeInstruction(Opcode.BNZ, vmDt, reg1=counterReg, labelSymbol = repeatLabel)
+        return code
+    }
+
+    private fun translate(jump: PtJump): VmCodeChunk {
+        val code = VmCodeChunk()
+        if(jump.address!=null)
+            throw AssemblyError("cannot jump to memory location in the vm target")
+        code += if(jump.generatedLabel!=null)
+            VmCodeInstruction(Opcode.JUMP, labelSymbol = listOf(jump.generatedLabel!!))
+        else if(jump.identifier!=null)
+            VmCodeInstruction(Opcode.JUMP, labelSymbol = jump.identifier!!.targetName)
+        else
+            throw AssemblyError("weird jump")
+        return code
+    }
+
+    private fun translateGroup(group: List<PtNode>): VmCodeChunk {
+        val code = VmCodeChunk()
+        group.forEach { code += translateNode(it) }
+        return code
+    }
+
+    private fun translate(ret: PtReturn): VmCodeChunk {
+        val code = VmCodeChunk()
+        val value = ret.value
+        if(value!=null) {
+            // Call Convention: return value is always returned in r0 (or fr0 if float)
+            code += if(value.type==DataType.FLOAT)
+                expressionEval.translateExpression(value, -1, 0)
+            else
+                expressionEval.translateExpression(value, 0, -1)
+        }
+        code += VmCodeInstruction(Opcode.RETURN)
+        return code
+    }
+
+    private fun translate(sub: PtSub): VmCodeChunk {
+        val code = VmCodeChunk()
+        code += VmCodeComment("SUB: ${sub.scopedName} -> ${sub.returntype}")
+        code += VmCodeLabel(sub.scopedName)
+        for (child in sub.children) {
+            code += translateNode(child)
+        }
+        code += VmCodeComment("SUB-END '${sub.name}'")
+        return code
+    }
+
+    private fun translate(block: PtBlock): VmCodeChunk {
+        val code = VmCodeChunk()
+        code += VmCodeComment("BLOCK '${block.name}'  addr=${block.address}  lib=${block.library}")
+        for (child in block.children) {
+            if(child !is PtAssignment) // global variable initialization is done elsewhere
+                code += translateNode(child)
+        }
+        code += VmCodeComment("BLOCK-END '${block.name}'")
+        return code
+    }
+
+
+    internal fun vmType(type: DataType): VmDataType {
+        return when(type) {
+            DataType.UBYTE,
+            DataType.BYTE -> VmDataType.BYTE
+            DataType.UWORD,
+            DataType.WORD -> VmDataType.WORD
+            DataType.FLOAT -> VmDataType.FLOAT
+            in PassByReferenceDatatypes -> VmDataType.WORD
+            else -> throw AssemblyError("no vm datatype for $type")
+        }
+    }
+
+    private var labelSequenceNumber = 0
+    internal fun createLabelName(): List<String> {
+        labelSequenceNumber++
+        return listOf("prog8_label_gen_$labelSequenceNumber")
+    }
+
+    internal fun translateBuiltinFunc(call: PtBuiltinFunctionCall, resultRegister: Int): VmCodeChunk =
+        builtinFuncGen.translate(call, resultRegister)
+
+    internal fun isZero(expression: PtExpression): Boolean = expression is PtNumber && expression.number==0.0
+
+    internal fun isOne(expression: PtExpression): Boolean = expression is PtNumber && expression.number==1.0
+}
+

codeGenVirtual/src/prog8/codegen/virtual/ExpressionGen.kt

@@ -0,0 +1,846 @@
+package prog8.codegen.virtual
+
+import prog8.code.StStaticVariable
+import prog8.code.StSub
+import prog8.code.ast.*
+import prog8.code.core.*
+import prog8.vm.Opcode
+import prog8.vm.VmDataType
+
+
+internal class ExpressionGen(private val codeGen: CodeGen) {
+    fun translateExpression(expr: PtExpression, resultRegister: Int, resultFpRegister: Int): VmCodeChunk {
+        require(codeGen.vmRegisters.peekNext() > resultRegister)
+
+        val code = VmCodeChunk()
+
+        when (expr) {
+            is PtMachineRegister -> {
+                if(resultRegister!=expr.register) {
+                    val vmDt = codeGen.vmType(expr.type)
+                    code += VmCodeInstruction(Opcode.LOADR, vmDt, reg1=resultRegister, reg2=expr.register)
+                }
+            }
+            is PtNumber -> {
+                val vmDt = codeGen.vmType(expr.type)
+                code += if(vmDt==VmDataType.FLOAT)
+                    VmCodeInstruction(Opcode.LOAD, vmDt, fpReg1 = resultFpRegister, fpValue = expr.number.toFloat())
+                else
+                    VmCodeInstruction(Opcode.LOAD, vmDt, reg1=resultRegister, value=expr.number.toInt())
+            }
+            is PtIdentifier -> {
+                val vmDt = codeGen.vmType(expr.type)
+                val mem = codeGen.allocations.get(expr.targetName)
+                code += if (expr.type in PassByValueDatatypes) {
+                    if(vmDt==VmDataType.FLOAT)
+                        VmCodeInstruction(Opcode.LOADM, vmDt, fpReg1 = resultFpRegister, value = mem)
+                    else
+                        VmCodeInstruction(Opcode.LOADM, vmDt, reg1 = resultRegister, value = mem)
+                } else {
+                    // for strings and arrays etc., load the *address* of the value instead
+                    VmCodeInstruction(Opcode.LOAD, vmDt, reg1 = resultRegister, value = mem)
+                }
+            }
+            is PtAddressOf -> {
+                val vmDt = codeGen.vmType(expr.type)
+                val mem = codeGen.allocations.get(expr.identifier.targetName)
+                code += VmCodeInstruction(Opcode.LOAD, vmDt, reg1=resultRegister, value=mem)
+            }
+            is PtMemoryByte -> {
+                if(expr.address is PtNumber) {
+                    val address = (expr.address as PtNumber).number.toInt()
+                    code += VmCodeInstruction(Opcode.LOADM, VmDataType.BYTE, reg1=resultRegister, value = address)
+                } else {
+                    val addressRegister = codeGen.vmRegisters.nextFree()
+                    code += translateExpression(expr.address, addressRegister, -1)
+                    code += VmCodeInstruction(Opcode.LOADI, VmDataType.BYTE, reg1=resultRegister, reg2=addressRegister)
+                }
+            }
+            is PtTypeCast -> code += translate(expr, resultRegister, resultFpRegister)
+            is PtPrefix -> code += translate(expr, resultRegister)
+            is PtArrayIndexer -> code += translate(expr, resultRegister, resultFpRegister)
+            is PtBinaryExpression -> code += translate(expr, resultRegister, resultFpRegister)
+            is PtBuiltinFunctionCall -> code += codeGen.translateBuiltinFunc(expr, resultRegister)
+            is PtFunctionCall -> code += translate(expr, resultRegister, resultFpRegister)
+            is PtContainmentCheck -> code += translate(expr, resultRegister, resultFpRegister)
+            is PtPipe -> code += translate(expr, resultRegister)
+            is PtRange,
+            is PtArray,
+            is PtString -> throw AssemblyError("range/arrayliteral/string should no longer occur as expression")
+            else -> throw AssemblyError("weird expression")
+        }
+        return code
+    }
+
+    internal fun translate(pipe: PtPipe, resultRegister: Int): VmCodeChunk {
+        val segments = pipe.segments
+        var valueDt = segments[0].type
+        var valueReg = if(pipe.void) codeGen.vmRegisters.nextFree() else resultRegister
+
+        fun addImplicitArgToSegment(segment: PtExpression, sourceReg: Int, sourceDt: DataType): PtExpression {
+            return when (segment) {
+                is PtFunctionCall -> {
+                    val segWithArg = PtFunctionCall(segment.functionName, segment.void, segment.type, segment.position)
+                    segWithArg.children.add(PtMachineRegister(sourceReg, sourceDt, segment.position))
+                    segWithArg.children.addAll(segment.args)
+                    segWithArg
+                }
+                is PtBuiltinFunctionCall -> {
+                    val segWithArg = PtBuiltinFunctionCall(segment.name, segment.void, segment.hasNoSideEffects, segment.type, segment.position)
+                    segWithArg.children.add(PtMachineRegister(sourceReg, sourceDt, segment.position))
+                    segWithArg.children.addAll(segment.args)
+                    segWithArg
+                }
+                else -> throw AssemblyError("weird segment type")
+            }
+        }
+
+        val code = VmCodeChunk()
+        code += translateExpression(segments[0], valueReg, -1)
+        for (segment in segments.subList(1, segments.size-1)) {
+            val sourceReg = valueReg
+            val sourceDt = valueDt
+            if(segment.type!=valueDt) {
+                valueDt = segment.type
+                valueReg = codeGen.vmRegisters.nextFree()
+            }
+            val segmentWithImplicitArgument = addImplicitArgToSegment(segment, sourceReg, sourceDt)
+            code += translateExpression(segmentWithImplicitArgument, valueReg, -1)
+        }
+        val segWithArg = addImplicitArgToSegment(segments.last(), valueReg, valueDt)
+        code += translateExpression(segWithArg, resultRegister, -1)
+        return code
+    }
+
+    private fun translate(check: PtContainmentCheck, resultRegister: Int, resultFpRegister: Int): VmCodeChunk {
+        val code = VmCodeChunk()
+        code += translateExpression(check.element, resultRegister, -1)   // load the element to check in resultRegister
+        val iterable = codeGen.symbolTable.flat.getValue(check.iterable.targetName) as StStaticVariable
+        when(iterable.dt) {
+            DataType.STR -> {
+                val call = PtFunctionCall(listOf("prog8_lib", "string_contains"), false, DataType.UBYTE, check.position)
+                call.children.add(check.element)
+                call.children.add(check.iterable)
+                code += translate(call, resultRegister, resultFpRegister)
+            }
+            DataType.ARRAY_UB, DataType.ARRAY_B -> {
+                val call = PtFunctionCall(listOf("prog8_lib", "bytearray_contains"), false, DataType.UBYTE, check.position)
+                call.children.add(check.element)
+                call.children.add(check.iterable)
+                call.children.add(PtNumber(DataType.UBYTE, iterable.length!!.toDouble(), iterable.position))
+                code += translate(call, resultRegister, resultFpRegister)
+            }
+            DataType.ARRAY_UW, DataType.ARRAY_W -> {
+                val call = PtFunctionCall(listOf("prog8_lib", "wordarray_contains"), false, DataType.UBYTE, check.position)
+                call.children.add(check.element)
+                call.children.add(check.iterable)
+                call.children.add(PtNumber(DataType.UBYTE, iterable.length!!.toDouble(), iterable.position))
+                code += translate(call, resultRegister, resultFpRegister)
+            }
+            DataType.ARRAY_F -> throw AssemblyError("containment check in float-array not supported")
+            else -> throw AssemblyError("weird iterable dt ${iterable.dt} for ${check.iterable.targetName}")
+        }
+        return code
+    }
+
+    private fun translate(arrayIx: PtArrayIndexer, resultRegister: Int, resultFpRegister: Int): VmCodeChunk {
+        val eltSize = codeGen.program.memsizer.memorySize(arrayIx.type)
+        val vmDt = codeGen.vmType(arrayIx.type)
+        val code = VmCodeChunk()
+        val idxReg = codeGen.vmRegisters.nextFree()
+        val arrayLocation = codeGen.allocations.get(arrayIx.variable.targetName)
+        if(arrayIx.index is PtNumber) {
+            // optimized code when index is known - just calculate the memory address here
+            val memOffset = (arrayIx.index as PtNumber).number.toInt() * eltSize
+            if(vmDt==VmDataType.FLOAT)
+                code += VmCodeInstruction(Opcode.LOADM, VmDataType.FLOAT, fpReg1=resultFpRegister, value=arrayLocation+memOffset)
+            else
+                code += VmCodeInstruction(Opcode.LOADM, vmDt, reg1=resultRegister, value=arrayLocation+memOffset)
+        } else {
+            code += translateExpression(arrayIx.index, idxReg, -1)
+            if(eltSize>1)
+                code += codeGen.multiplyByConst(VmDataType.BYTE, idxReg, eltSize)
+            if(vmDt==VmDataType.FLOAT)
+                code += VmCodeInstruction(Opcode.LOADX, VmDataType.FLOAT, fpReg1 = resultFpRegister, reg1=idxReg, value = arrayLocation)
+            else
+                code += VmCodeInstruction(Opcode.LOADX, vmDt, reg1=resultRegister, reg2=idxReg, value = arrayLocation)
+        }
+        return code
+    }
+
+    private fun translate(expr: PtPrefix, resultRegister: Int): VmCodeChunk {
+        val code = VmCodeChunk()
+        code += translateExpression(expr.value, resultRegister, -1)
+        val vmDt = codeGen.vmType(expr.type)
+        when(expr.operator) {
+            "+" -> { }
+            "-" -> {
+                code += VmCodeInstruction(Opcode.NEG, vmDt, reg1=resultRegister)
+            }
+            "~" -> {
+                val regMask = codeGen.vmRegisters.nextFree()
+                val mask = if(vmDt==VmDataType.BYTE) 0x00ff else 0xffff
+                code += VmCodeInstruction(Opcode.LOAD, vmDt, reg1=regMask, value=mask)
+                code += VmCodeInstruction(Opcode.XOR, vmDt, reg1=resultRegister, reg2=regMask)
+            }
+            "not" -> {
+                code += VmCodeInstruction(Opcode.NOT, vmDt, reg1=resultRegister)
+            }
+            else -> throw AssemblyError("weird prefix operator")
+        }
+        return code
+    }
+
+    private fun translate(cast: PtTypeCast, predefinedResultRegister: Int, predefinedResultFpRegister: Int): VmCodeChunk {
+        val code = VmCodeChunk()
+        if(cast.type==cast.value.type)
+            return code
+        val actualResultFpReg = if(predefinedResultFpRegister>=0) predefinedResultFpRegister else codeGen.vmRegisters.nextFreeFloat()
+        val actualResultReg = if(predefinedResultRegister>=0) predefinedResultRegister else codeGen.vmRegisters.nextFree()
+        if(cast.value.type==DataType.FLOAT) {
+            // a cast from float to integer, so evaluate the value into a float register first
+            code += translateExpression(cast.value, -1, actualResultFpReg)
+        }
+        else
+            code += translateExpression(cast.value, actualResultReg, -1)
+        when(cast.type) {
+            DataType.UBYTE -> {
+                when(cast.value.type) {
+                    DataType.BYTE, DataType.UWORD, DataType.WORD -> { /* just keep the LSB as it is */ }
+                    DataType.FLOAT -> code += VmCodeInstruction(Opcode.FTOUB, VmDataType.FLOAT, reg1=actualResultReg, fpReg1 = actualResultFpReg)
+                    else -> throw AssemblyError("weird cast value type")
+                }
+            }
+            DataType.BYTE -> {
+                when(cast.value.type) {
+                    DataType.UBYTE, DataType.UWORD, DataType.WORD -> { /* just keep the LSB as it is */ }
+                    DataType.FLOAT -> code += VmCodeInstruction(Opcode.FTOSB, VmDataType.FLOAT, reg1=actualResultReg, fpReg1 = actualResultFpReg)
+                    else -> throw AssemblyError("weird cast value type")
+                }
+            }
+            DataType.UWORD -> {
+                when(cast.value.type) {
+                    DataType.BYTE -> {
+                        // byte -> uword:   sign extend
+                        code += VmCodeInstruction(Opcode.EXTS, type = VmDataType.BYTE, reg1 = actualResultReg)
+                    }
+                    DataType.UBYTE -> {
+                        // ubyte -> uword:   sign extend
+                        code += VmCodeInstruction(Opcode.EXT, type = VmDataType.BYTE, reg1 = actualResultReg)
+                    }
+                    DataType.WORD -> { }
+                    DataType.FLOAT -> {
+                        code += VmCodeInstruction(Opcode.FTOUW, VmDataType.FLOAT, reg1=actualResultReg, fpReg1 = actualResultFpReg)
+                    }
+                    else -> throw AssemblyError("weird cast value type")
+                }
+            }
+            DataType.WORD -> {
+                when(cast.value.type) {
+                    DataType.BYTE -> {
+                        // byte -> word:   sign extend
+                        code += VmCodeInstruction(Opcode.EXTS, type = VmDataType.BYTE, reg1 = actualResultReg)
+                    }
+                    DataType.UBYTE -> {
+                        // byte -> word:   sign extend
+                        code += VmCodeInstruction(Opcode.EXT, type = VmDataType.BYTE, reg1 = actualResultReg)
+                    }
+                    DataType.UWORD -> { }
+                    DataType.FLOAT -> {
+                        code += VmCodeInstruction(Opcode.FTOSW, VmDataType.FLOAT, reg1=actualResultReg, fpReg1 = actualResultFpReg)
+                    }
+                    else -> throw AssemblyError("weird cast value type")
+                }
+            }
+            DataType.FLOAT -> {
+                when(cast.value.type) {
+                    DataType.UBYTE -> {
+                        code += VmCodeInstruction(Opcode.FFROMUB, VmDataType.FLOAT, reg1=actualResultReg, fpReg1 = actualResultFpReg)
+                    }
+                    DataType.BYTE -> {
+                        code += VmCodeInstruction(Opcode.FFROMSB, VmDataType.FLOAT, reg1=actualResultReg, fpReg1 = actualResultFpReg)
+                    }
+                    DataType.UWORD -> {
+                        code += VmCodeInstruction(Opcode.FFROMUW, VmDataType.FLOAT, reg1=actualResultReg, fpReg1 = actualResultFpReg)
+                    }
+                    DataType.WORD -> {
+                        code += VmCodeInstruction(Opcode.FFROMSW, VmDataType.FLOAT, reg1=actualResultReg, fpReg1 = actualResultFpReg)
+                    }
+                    else -> throw AssemblyError("weird cast value type")
+                }
+            }
+            else -> throw AssemblyError("weird cast type")
+        }
+        return code
+    }
+
+    private fun translate(binExpr: PtBinaryExpression, resultRegister: Int, resultFpRegister: Int): VmCodeChunk {
+        val vmDt = codeGen.vmType(binExpr.left.type)
+        val signed = binExpr.left.type in SignedDatatypes
+        return when(binExpr.operator) {
+            "+" -> operatorPlus(binExpr, vmDt, resultRegister, resultFpRegister)
+            "-" -> operatorMinus(binExpr, vmDt, resultRegister, resultFpRegister)
+            "*" -> operatorMultiply(binExpr, vmDt, resultRegister, resultFpRegister)
+            "/" -> operatorDivide(binExpr, vmDt, resultRegister, resultFpRegister, signed)
+            "%" -> operatorModulo(binExpr, vmDt, resultRegister)
+            "|", "or" -> operatorOr(binExpr, vmDt, resultRegister)
+            "&", "and" -> operatorAnd(binExpr, vmDt, resultRegister)
+            "^", "xor" -> operatorXor(binExpr, vmDt, resultRegister)
+            "<<" -> operatorShiftLeft(binExpr, vmDt, resultRegister)
+            ">>" -> operatorShiftRight(binExpr, vmDt, resultRegister, signed)
+            "==" -> operatorEquals(binExpr, vmDt, resultRegister, false)
+            "!=" -> operatorEquals(binExpr, vmDt, resultRegister, true)
+            "<" -> operatorLessThan(binExpr, vmDt, resultRegister, signed, false)
+            ">" -> operatorGreaterThan(binExpr, vmDt, resultRegister, signed, false)
+            "<=" -> operatorLessThan(binExpr, vmDt, resultRegister, signed, true)
+            ">=" -> operatorGreaterThan(binExpr, vmDt, resultRegister, signed, true)
+            else -> throw AssemblyError("weird operator ${binExpr.operator}")
+        }
+    }
+
+    private fun operatorGreaterThan(
+        binExpr: PtBinaryExpression,
+        vmDt: VmDataType,
+        resultRegister: Int,
+        signed: Boolean,
+        greaterEquals: Boolean
+    ): VmCodeChunk {
+        val code = VmCodeChunk()
+        if(vmDt==VmDataType.FLOAT) {
+            val leftFpReg = codeGen.vmRegisters.nextFreeFloat()
+            val rightFpReg = codeGen.vmRegisters.nextFreeFloat()
+            val zeroRegister = codeGen.vmRegisters.nextFree()
+            code += translateExpression(binExpr.left, -1, leftFpReg)
+            code += translateExpression(binExpr.right, -1, rightFpReg)
+            code += VmCodeInstruction(Opcode.FCOMP, VmDataType.FLOAT, reg1=resultRegister, fpReg1 = leftFpReg, fpReg2 = rightFpReg)
+            code += VmCodeInstruction(Opcode.LOAD, VmDataType.BYTE, reg1=zeroRegister, value=0)
+            val ins = if (signed) {
+                if (greaterEquals) Opcode.SGES else Opcode.SGTS
+            } else {
+                if (greaterEquals) Opcode.SGE else Opcode.SGT
+            }
+            code += VmCodeInstruction(ins, VmDataType.BYTE, reg1 = resultRegister, reg2 = zeroRegister)
+        } else {
+            if(binExpr.left.type==DataType.STR && binExpr.right.type==DataType.STR) {
+                val comparisonCall = PtFunctionCall(listOf("prog8_lib", "string_compare"), false, DataType.BYTE, Position.DUMMY)
+                comparisonCall.children.add(binExpr.left)
+                comparisonCall.children.add(binExpr.right)
+                code += translate(comparisonCall, resultRegister, -1)
+                val zeroRegister = codeGen.vmRegisters.nextFree()
+                code += VmCodeInstruction(Opcode.LOAD, VmDataType.BYTE, reg1=zeroRegister, value=0)
+                code += if(greaterEquals)
+                    VmCodeInstruction(Opcode.SGES, VmDataType.BYTE, reg1=resultRegister, reg2=zeroRegister)
+                else
+                    VmCodeInstruction(Opcode.SGTS, VmDataType.BYTE, reg1=resultRegister, reg2=zeroRegister)
+            } else {
+                val rightResultReg = codeGen.vmRegisters.nextFree()
+                code += translateExpression(binExpr.left, resultRegister, -1)
+                code += translateExpression(binExpr.right, rightResultReg, -1)
+                val ins = if (signed) {
+                    if (greaterEquals) Opcode.SGES else Opcode.SGTS
+                } else {
+                    if (greaterEquals) Opcode.SGE else Opcode.SGT
+                }
+                code += VmCodeInstruction(ins, vmDt, reg1 = resultRegister, reg2 = rightResultReg)
+            }
+        }
+        return code
+    }
+
+    private fun operatorLessThan(
+        binExpr: PtBinaryExpression,
+        vmDt: VmDataType,
+        resultRegister: Int,
+        signed: Boolean,
+        lessEquals: Boolean
+    ): VmCodeChunk {
+        val code = VmCodeChunk()
+        if(vmDt==VmDataType.FLOAT) {
+            val leftFpReg = codeGen.vmRegisters.nextFreeFloat()
+            val rightFpReg = codeGen.vmRegisters.nextFreeFloat()
+            val zeroRegister = codeGen.vmRegisters.nextFree()
+            code += translateExpression(binExpr.left, -1, leftFpReg)
+            code += translateExpression(binExpr.right, -1, rightFpReg)
+            code += VmCodeInstruction(Opcode.FCOMP, VmDataType.FLOAT, reg1=resultRegister, fpReg1 = leftFpReg, fpReg2 = rightFpReg)
+            code += VmCodeInstruction(Opcode.LOAD, VmDataType.BYTE, reg1=zeroRegister, value=0)
+            val ins = if (signed) {
+                if (lessEquals) Opcode.SLES else Opcode.SLTS
+            } else {
+                if (lessEquals) Opcode.SLE else Opcode.SLT
+            }
+            code += VmCodeInstruction(ins, VmDataType.BYTE, reg1 = resultRegister, reg2 = zeroRegister)
+        } else {
+            if(binExpr.left.type==DataType.STR && binExpr.right.type==DataType.STR) {
+                val comparisonCall = PtFunctionCall(listOf("prog8_lib", "string_compare"), false, DataType.BYTE, Position.DUMMY)
+                comparisonCall.children.add(binExpr.left)
+                comparisonCall.children.add(binExpr.right)
+                code += translate(comparisonCall, resultRegister, -1)
+                val zeroRegister = codeGen.vmRegisters.nextFree()
+                code += VmCodeInstruction(Opcode.LOAD, VmDataType.BYTE, reg1=zeroRegister, value=0)
+                code += if(lessEquals)
+                    VmCodeInstruction(Opcode.SLES, VmDataType.BYTE, reg1=resultRegister, reg2=zeroRegister)
+                else
+                    VmCodeInstruction(Opcode.SLTS, VmDataType.BYTE, reg1=resultRegister, reg2=zeroRegister)
+            } else {
+                val rightResultReg = codeGen.vmRegisters.nextFree()
+                code += translateExpression(binExpr.left, resultRegister, -1)
+                code += translateExpression(binExpr.right, rightResultReg, -1)
+                val ins = if (signed) {
+                    if (lessEquals) Opcode.SLES else Opcode.SLTS
+                } else {
+                    if (lessEquals) Opcode.SLE else Opcode.SLT
+                }
+                code += VmCodeInstruction(ins, vmDt, reg1 = resultRegister, reg2 = rightResultReg)
+            }
+        }
+        return code
+    }
+
+    private fun operatorEquals(binExpr: PtBinaryExpression, vmDt: VmDataType, resultRegister: Int, notEquals: Boolean): VmCodeChunk {
+        val code = VmCodeChunk()
+        if(vmDt==VmDataType.FLOAT) {
+            val leftFpReg = codeGen.vmRegisters.nextFreeFloat()
+            val rightFpReg = codeGen.vmRegisters.nextFreeFloat()
+            code += translateExpression(binExpr.left, -1, leftFpReg)
+            code += translateExpression(binExpr.right, -1, rightFpReg)
+            if (notEquals) {
+                code += VmCodeInstruction(Opcode.FCOMP, VmDataType.FLOAT, reg1=resultRegister, fpReg1 = leftFpReg, fpReg2 = rightFpReg)
+            } else {
+                val label = codeGen.createLabelName()
+                val valueReg = codeGen.vmRegisters.nextFree()
+                code += VmCodeInstruction(Opcode.LOAD, VmDataType.BYTE, reg1=resultRegister, value=1)
+                code += VmCodeInstruction(Opcode.FCOMP, VmDataType.FLOAT, reg1=valueReg, fpReg1 = leftFpReg, fpReg2 = rightFpReg)
+                code += VmCodeInstruction(Opcode.BZ, VmDataType.BYTE, reg1=valueReg, labelSymbol = label)
+                code += VmCodeInstruction(Opcode.LOAD, VmDataType.BYTE, reg1=resultRegister, value=0)
+                code += VmCodeLabel(label)
+            }
+        } else {
+            if(binExpr.left.type==DataType.STR && binExpr.right.type==DataType.STR) {
+                val comparisonCall = PtFunctionCall(listOf("prog8_lib", "string_compare"), false, DataType.BYTE, Position.DUMMY)
+                comparisonCall.children.add(binExpr.left)
+                comparisonCall.children.add(binExpr.right)
+                code += translate(comparisonCall, resultRegister, -1)
+                if(notEquals) {
+                    val maskReg = codeGen.vmRegisters.nextFree()
+                    code += VmCodeInstruction(Opcode.LOAD, vmDt, reg1=maskReg, value=1)
+                    code += VmCodeInstruction(Opcode.AND, vmDt, reg1=resultRegister, reg2=maskReg)
+                } else {
+                    code += VmCodeInstruction(Opcode.NOT, vmDt, reg1=resultRegister)
+                }
+            } else {
+                val rightResultReg = codeGen.vmRegisters.nextFree()
+                code += translateExpression(binExpr.left, resultRegister, -1)
+                code += translateExpression(binExpr.right, rightResultReg, -1)
+                val opcode = if (notEquals) Opcode.SNE else Opcode.SEQ
+                code += VmCodeInstruction(opcode, vmDt, reg1 = resultRegister, reg2 = rightResultReg)
+            }
+        }
+        return code
+    }
+
+    private fun operatorShiftRight(binExpr: PtBinaryExpression, vmDt: VmDataType, resultRegister: Int, signed: Boolean): VmCodeChunk {
+        val code = VmCodeChunk()
+        if(codeGen.isOne(binExpr.right)) {
+            code += translateExpression(binExpr.left, resultRegister, -1)
+            val opc = if (signed) Opcode.ASR else Opcode.LSR
+            code += VmCodeInstruction(opc, vmDt, reg1 = resultRegister)
+        } else {
+            val rightResultReg = codeGen.vmRegisters.nextFree()
+            code += translateExpression(binExpr.left, resultRegister, -1)
+            code += translateExpression(binExpr.right, rightResultReg, -1)
+            val opc = if (signed) Opcode.ASRN else Opcode.LSRN
+            code += VmCodeInstruction(opc, vmDt, reg1 = resultRegister, reg2 = rightResultReg)
+        }
+        return code
+    }
+
+    internal fun operatorShiftRightInplace(address: Int, vmDt: VmDataType,  signed: Boolean, operand: PtExpression): VmCodeChunk {
+        val code = VmCodeChunk()
+        if(codeGen.isOne(operand)) {
+            val opc = if (signed) Opcode.ASRM else Opcode.LSRM
+            code += VmCodeInstruction(opc, vmDt, value=address)
+        } else {
+            val operandReg = codeGen.vmRegisters.nextFree()
+            code += translateExpression(operand, operandReg, -1)
+            val opc = if (signed) Opcode.ASRNM else Opcode.LSRNM
+            code += VmCodeInstruction(opc, vmDt, reg1 = operandReg, value=address)
+        }
+        return code
+    }
+
+    private fun operatorShiftLeft(binExpr: PtBinaryExpression, vmDt: VmDataType, resultRegister: Int): VmCodeChunk {
+        val code = VmCodeChunk()
+        if(codeGen.isOne(binExpr.right)){
+            code += translateExpression(binExpr.left, resultRegister, -1)
+            code += VmCodeInstruction(Opcode.LSL, vmDt, reg1=resultRegister)
+        } else {
+            val rightResultReg = codeGen.vmRegisters.nextFree()
+            code += translateExpression(binExpr.left, resultRegister, -1)
+            code += translateExpression(binExpr.right, rightResultReg, -1)
+            code += VmCodeInstruction(Opcode.LSLN, vmDt, reg1=resultRegister, rightResultReg)
+        }
+        return code
+    }
+
+    internal fun operatorShiftLeftInplace(address: Int, vmDt: VmDataType, operand: PtExpression): VmCodeChunk {
+        val code = VmCodeChunk()
+        if(codeGen.isOne(operand)){
+            code += VmCodeInstruction(Opcode.LSLM, vmDt, value=address)
+        } else {
+            val operandReg = codeGen.vmRegisters.nextFree()
+            code += translateExpression(operand, operandReg, -1)
+            code += VmCodeInstruction(Opcode.LSLNM, vmDt, reg1=operandReg, value=address)
+        }
+        return code
+    }
+
+    private fun operatorXor(binExpr: PtBinaryExpression, vmDt: VmDataType, resultRegister: Int): VmCodeChunk {
+        val code = VmCodeChunk()
+        val rightResultReg = codeGen.vmRegisters.nextFree()
+        code += translateExpression(binExpr.left, resultRegister, -1)
+        code += translateExpression(binExpr.right, rightResultReg, -1)
+        code += VmCodeInstruction(Opcode.XOR, vmDt, reg1=resultRegister, reg2=rightResultReg)
+        return code
+    }
+
+    internal fun operatorXorInplace(address: Int, vmDt: VmDataType, operand: PtExpression): VmCodeChunk {
+        val code = VmCodeChunk()
+        val operandReg = codeGen.vmRegisters.nextFree()
+        code += translateExpression(operand, operandReg, -1)
+        code += VmCodeInstruction(Opcode.XORM, vmDt, reg1=operandReg, value = address)
+        return code
+    }
+
+    private fun operatorAnd(binExpr: PtBinaryExpression, vmDt: VmDataType, resultRegister: Int): VmCodeChunk {
+        val code = VmCodeChunk()
+        val rightResultReg = codeGen.vmRegisters.nextFree()
+        code += translateExpression(binExpr.left, resultRegister, -1)
+        code += translateExpression(binExpr.right, rightResultReg, -1)
+        code += VmCodeInstruction(Opcode.AND, vmDt, reg1=resultRegister, reg2=rightResultReg)
+        return code
+    }
+
+    internal  fun operatorAndInplace(address: Int, vmDt: VmDataType, operand: PtExpression): VmCodeChunk {
+        val code = VmCodeChunk()
+        val operandReg = codeGen.vmRegisters.nextFree()
+        code += translateExpression(operand, operandReg, -1)
+        code += VmCodeInstruction(Opcode.ANDM, vmDt, reg1=operandReg, value=address)
+        return code
+    }
+
+    private fun operatorOr(binExpr: PtBinaryExpression, vmDt: VmDataType, resultRegister: Int): VmCodeChunk {
+        val code = VmCodeChunk()
+        val rightResultReg = codeGen.vmRegisters.nextFree()
+        code += translateExpression(binExpr.left, resultRegister, -1)
+        code += translateExpression(binExpr.right, rightResultReg, -1)
+        code += VmCodeInstruction(Opcode.OR, vmDt, reg1=resultRegister, reg2=rightResultReg)
+        return code
+    }
+
+    internal fun operatorOrInplace(address: Int, vmDt: VmDataType, operand: PtExpression): VmCodeChunk {
+        val code = VmCodeChunk()
+        val operandReg = codeGen.vmRegisters.nextFree()
+        code += translateExpression(operand, operandReg, -1)
+        code += VmCodeInstruction(Opcode.ORM, vmDt, reg1=operandReg, value = address)
+        return code
+    }
+
+    private fun operatorModulo(binExpr: PtBinaryExpression, vmDt: VmDataType, resultRegister: Int): VmCodeChunk {
+        if(vmDt==VmDataType.FLOAT)
+            throw IllegalArgumentException("floating-point modulo not supported")
+        val code = VmCodeChunk()
+        val rightResultReg = codeGen.vmRegisters.nextFree()
+        code += translateExpression(binExpr.left, resultRegister, -1)
+        code += translateExpression(binExpr.right, rightResultReg, -1)
+        code += VmCodeInstruction(Opcode.MOD, vmDt, reg1=resultRegister, reg2=rightResultReg)
+        return code
+    }
+
+    private fun operatorDivide(binExpr: PtBinaryExpression,
+                               vmDt: VmDataType,
+                               resultRegister: Int,
+                               resultFpRegister: Int,
+                               signed: Boolean): VmCodeChunk {
+        val code = VmCodeChunk()
+        val constFactorRight = binExpr.right as? PtNumber
+        if(vmDt==VmDataType.FLOAT) {
+            if(constFactorRight!=null && constFactorRight.type!=DataType.FLOAT) {
+                code += translateExpression(binExpr.left, -1, resultFpRegister)
+                val factor = constFactorRight.number.toFloat()
+                code += codeGen.divideByConstFloat(resultFpRegister, factor)
+            } else {
+                val rightResultFpReg = codeGen.vmRegisters.nextFreeFloat()
+                code += translateExpression(binExpr.left, -1, resultFpRegister)
+                code += translateExpression(binExpr.right, -1, rightResultFpReg)
+                code += if(signed)
+                    VmCodeInstruction(Opcode.DIVS, vmDt, fpReg1 = resultFpRegister, fpReg2=rightResultFpReg)
+                else
+                    VmCodeInstruction(Opcode.DIV, vmDt, fpReg1 = resultFpRegister, fpReg2=rightResultFpReg)
+            }
+        } else {
+            if(constFactorRight!=null && constFactorRight.type!=DataType.FLOAT) {
+                code += translateExpression(binExpr.left, resultRegister, -1)
+                val factor = constFactorRight.number.toInt()
+                code += codeGen.divideByConst(vmDt, resultRegister, factor, signed)
+            } else {
+                val rightResultReg = codeGen.vmRegisters.nextFree()
+                code += translateExpression(binExpr.left, resultRegister, -1)
+                code += translateExpression(binExpr.right, rightResultReg, -1)
+                code += if(signed)
+                    VmCodeInstruction(Opcode.DIVS, vmDt, reg1=resultRegister, reg2=rightResultReg)
+                else
+                    VmCodeInstruction(Opcode.DIV, vmDt, reg1=resultRegister, reg2=rightResultReg)
+            }
+        }
+        return code
+    }
+
+    internal fun operatorDivideInplace(address: Int, vmDt: VmDataType, signed: Boolean, operand: PtExpression): VmCodeChunk {
+        val code = VmCodeChunk()
+        val constFactorRight = operand as? PtNumber
+        if(vmDt==VmDataType.FLOAT) {
+            if(constFactorRight!=null && constFactorRight.type!=DataType.FLOAT) {
+                val factor = constFactorRight.number.toFloat()
+                code += codeGen.divideByConstFloatInplace(address, factor)
+            } else {
+                val operandFpReg = codeGen.vmRegisters.nextFreeFloat()
+                code += translateExpression(operand, -1, operandFpReg)
+                code += if(signed)
+                    VmCodeInstruction(Opcode.DIVSM, vmDt, fpReg1 = operandFpReg, value=address)
+                else
+                    VmCodeInstruction(Opcode.DIVM, vmDt, fpReg1 = operandFpReg, value=address)
+            }
+        } else {
+            if(constFactorRight!=null && constFactorRight.type!=DataType.FLOAT) {
+                val factor = constFactorRight.number.toInt()
+                code += codeGen.divideByConstInplace(vmDt, address, factor, signed)
+            } else {
+                val operandReg = codeGen.vmRegisters.nextFree()
+                code += translateExpression(operand, operandReg, -1)
+                code += if(signed)
+                    VmCodeInstruction(Opcode.DIVSM, vmDt, reg1=operandReg, value = address)
+                else
+                    VmCodeInstruction(Opcode.DIVM, vmDt, reg1=operandReg, value = address)
+            }
+        }
+        return code
+    }
+
+    private fun operatorMultiply(binExpr: PtBinaryExpression, vmDt: VmDataType, resultRegister: Int, resultFpRegister: Int): VmCodeChunk {
+        val code = VmCodeChunk()
+        val constFactorLeft = binExpr.left as? PtNumber
+        val constFactorRight = binExpr.right as? PtNumber
+        if(vmDt==VmDataType.FLOAT) {
+            if(constFactorLeft!=null) {
+                code += translateExpression(binExpr.right, -1, resultFpRegister)
+                val factor = constFactorLeft.number.toFloat()
+                code += codeGen.multiplyByConstFloat(resultFpRegister, factor)
+            } else if(constFactorRight!=null) {
+                code += translateExpression(binExpr.left, -1, resultFpRegister)
+                val factor = constFactorRight.number.toFloat()
+                code += codeGen.multiplyByConstFloat(resultFpRegister, factor)
+            } else {
+                val rightResultFpReg = codeGen.vmRegisters.nextFreeFloat()
+                code += translateExpression(binExpr.left, -1, resultFpRegister)
+                code += translateExpression(binExpr.right, -1, rightResultFpReg)
+                code += VmCodeInstruction(Opcode.MUL, vmDt, fpReg1 = resultFpRegister, fpReg2 = rightResultFpReg)
+            }
+        } else {
+            if(constFactorLeft!=null && constFactorLeft.type!=DataType.FLOAT) {
+                code += translateExpression(binExpr.right, resultRegister, -1)
+                val factor = constFactorLeft.number.toInt()
+                code += codeGen.multiplyByConst(vmDt, resultRegister, factor)
+            } else if(constFactorRight!=null && constFactorRight.type!=DataType.FLOAT) {
+                code += translateExpression(binExpr.left, resultRegister, -1)
+                val factor = constFactorRight.number.toInt()
+                code += codeGen.multiplyByConst(vmDt, resultRegister, factor)
+            } else {
+                val rightResultReg = codeGen.vmRegisters.nextFree()
+                code += translateExpression(binExpr.left, resultRegister, -1)
+                code += translateExpression(binExpr.right, rightResultReg, -1)
+                code += VmCodeInstruction(Opcode.MUL, vmDt, reg1=resultRegister, reg2=rightResultReg)
+            }
+        }
+        return code
+    }
+
+    internal fun operatorMultiplyInplace(address: Int, vmDt: VmDataType, operand: PtExpression): VmCodeChunk {
+        val code = VmCodeChunk()
+        val constFactorRight = operand as? PtNumber
+        if(vmDt==VmDataType.FLOAT) {
+            if(constFactorRight!=null) {
+                val factor = constFactorRight.number.toFloat()
+                code += codeGen.multiplyByConstFloatInplace(address, factor)
+            } else {
+                val operandFpReg = codeGen.vmRegisters.nextFreeFloat()
+                code += translateExpression(operand, -1, operandFpReg)
+                code += VmCodeInstruction(Opcode.MULM, vmDt, fpReg1 = operandFpReg, value = address)
+            }
+        } else {
+            if(constFactorRight!=null && constFactorRight.type!=DataType.FLOAT) {
+                val factor = constFactorRight.number.toInt()
+                code += codeGen.multiplyByConstInplace(vmDt, address, factor)
+            } else {
+                val operandReg = codeGen.vmRegisters.nextFree()
+                code += translateExpression(operand, operandReg, -1)
+                code += VmCodeInstruction(Opcode.MULM, vmDt, reg1=operandReg, value = address)
+            }
+        }
+        return code
+    }
+
+    private fun operatorMinus(binExpr: PtBinaryExpression, vmDt: VmDataType, resultRegister: Int, resultFpRegister: Int): VmCodeChunk {
+        val code = VmCodeChunk()
+        if(vmDt==VmDataType.FLOAT) {
+            if((binExpr.right as? PtNumber)?.number==1.0) {
+                code += translateExpression(binExpr.left, -1, resultFpRegister)
+                code += VmCodeInstruction(Opcode.DEC, vmDt, fpReg1 = resultFpRegister)
+            }
+            else {
+                val rightResultFpReg = codeGen.vmRegisters.nextFreeFloat()
+                code += translateExpression(binExpr.left, -1, resultFpRegister)
+                code += translateExpression(binExpr.right, -1, rightResultFpReg)
+                code += VmCodeInstruction(Opcode.SUB, vmDt, fpReg1=resultFpRegister, fpReg2=rightResultFpReg)
+            }
+        } else {
+            if((binExpr.right as? PtNumber)?.number==1.0) {
+                code += translateExpression(binExpr.left, resultRegister, -1)
+                code += VmCodeInstruction(Opcode.DEC, vmDt, reg1=resultRegister)
+            }
+            else {
+                val rightResultReg = codeGen.vmRegisters.nextFree()
+                code += translateExpression(binExpr.left, resultRegister, -1)
+                code += translateExpression(binExpr.right, rightResultReg, -1)
+                code += VmCodeInstruction(Opcode.SUB, vmDt, reg1=resultRegister, reg2=rightResultReg)
+            }
+        }
+        return code
+    }
+
+    internal fun operatorMinusInplace(address: Int, vmDt: VmDataType, operand: PtExpression): VmCodeChunk {
+        val code = VmCodeChunk()
+        if(vmDt==VmDataType.FLOAT) {
+            if((operand as? PtNumber)?.number==1.0) {
+                code += VmCodeInstruction(Opcode.DECM, vmDt, value=address)
+            }
+            else {
+                val operandFpReg = codeGen.vmRegisters.nextFreeFloat()
+                code += translateExpression(operand, -1, operandFpReg)
+                code += VmCodeInstruction(Opcode.SUBM, vmDt, fpReg1=operandFpReg, value=address)
+            }
+        } else {
+            if((operand as? PtNumber)?.number==1.0) {
+                code += VmCodeInstruction(Opcode.DECM, vmDt, value=address)
+            }
+            else {
+                val operandReg = codeGen.vmRegisters.nextFree()
+                code += translateExpression(operand, operandReg, -1)
+                code += VmCodeInstruction(Opcode.SUBM, vmDt, reg1=operandReg, value = address)
+            }
+        }
+        return code
+    }
+
+    private fun operatorPlus(binExpr: PtBinaryExpression, vmDt: VmDataType, resultRegister: Int, resultFpRegister: Int): VmCodeChunk {
+        val code = VmCodeChunk()
+        if(vmDt==VmDataType.FLOAT) {
+            if((binExpr.left as? PtNumber)?.number==1.0) {
+                code += translateExpression(binExpr.right, -1, resultFpRegister)
+                code += VmCodeInstruction(Opcode.INC, vmDt, fpReg1=resultFpRegister)
+            }
+            else if((binExpr.right as? PtNumber)?.number==1.0) {
+                code += translateExpression(binExpr.left, -1, resultFpRegister)
+                code += VmCodeInstruction(Opcode.INC, vmDt, fpReg1=resultFpRegister)
+            }
+            else {
+                val rightResultFpReg = codeGen.vmRegisters.nextFreeFloat()
+                code += translateExpression(binExpr.left, -1, resultFpRegister)
+                code += translateExpression(binExpr.right, -1, rightResultFpReg)
+                code += VmCodeInstruction(Opcode.ADD, vmDt, fpReg1=resultFpRegister, fpReg2=rightResultFpReg)
+            }
+        } else {
+            if((binExpr.left as? PtNumber)?.number==1.0) {
+                code += translateExpression(binExpr.right, resultRegister, -1)
+                code += VmCodeInstruction(Opcode.INC, vmDt, reg1=resultRegister)
+            }
+            else if((binExpr.right as? PtNumber)?.number==1.0) {
+                code += translateExpression(binExpr.left, resultRegister, -1)
+                code += VmCodeInstruction(Opcode.INC, vmDt, reg1=resultRegister)
+            }
+            else {
+                val rightResultReg = codeGen.vmRegisters.nextFree()
+                code += translateExpression(binExpr.left, resultRegister, -1)
+                code += translateExpression(binExpr.right, rightResultReg, -1)
+                code += VmCodeInstruction(Opcode.ADD, vmDt, reg1=resultRegister, reg2=rightResultReg)
+            }
+        }
+        return code
+    }
+
+    internal fun operatorPlusInplace(address: Int, vmDt: VmDataType, operand: PtExpression): VmCodeChunk {
+        val code = VmCodeChunk()
+        if(vmDt==VmDataType.FLOAT) {
+            if((operand as? PtNumber)?.number==1.0) {
+                code += VmCodeInstruction(Opcode.INCM, vmDt, value = address)
+            }
+            else {
+                val operandFpReg = codeGen.vmRegisters.nextFreeFloat()
+                code += translateExpression(operand, -1, operandFpReg)
+                code += VmCodeInstruction(Opcode.ADDM, vmDt, fpReg1=operandFpReg, value=address)
+            }
+        } else {
+            if((operand as? PtNumber)?.number==1.0) {
+                code += VmCodeInstruction(Opcode.INCM, vmDt, value = address)
+            }
+            else {
+                val operandReg = codeGen.vmRegisters.nextFree()
+                code += translateExpression(operand, operandReg, -1)
+                code += VmCodeInstruction(Opcode.ADDM, vmDt, reg1=operandReg, value=address)
+            }
+        }
+        return code
+    }
+
+    fun translate(fcall: PtFunctionCall, resultRegister: Int, resultFpRegister: Int): VmCodeChunk {
+        val subroutine = codeGen.symbolTable.flat.getValue(fcall.functionName) as StSub
+        val code = VmCodeChunk()
+        for ((arg, parameter) in fcall.args.zip(subroutine.parameters)) {
+            val paramDt = codeGen.vmType(parameter.type)
+            if(codeGen.isZero(arg)) {
+                if (paramDt == VmDataType.FLOAT) {
+                    val mem = codeGen.allocations.get(fcall.functionName + parameter.name)
+                    code += VmCodeInstruction(Opcode.STOREZM, paramDt, value = mem)
+                } else {
+                    val mem = codeGen.allocations.get(fcall.functionName + parameter.name)
+                    code += VmCodeInstruction(Opcode.STOREZM, paramDt, value = mem)
+                }
+            } else {
+                if (paramDt == VmDataType.FLOAT) {
+                    val argFpReg = codeGen.vmRegisters.nextFreeFloat()
+                    code += translateExpression(arg, -1, argFpReg)
+                    val mem = codeGen.allocations.get(fcall.functionName + parameter.name)
+                    code += VmCodeInstruction(Opcode.STOREM, paramDt, fpReg1 = argFpReg, value = mem)
+                } else {
+                    val argReg = codeGen.vmRegisters.nextFree()
+                    code += translateExpression(arg, argReg, -1)
+                    val mem = codeGen.allocations.get(fcall.functionName + parameter.name)
+                    code += VmCodeInstruction(Opcode.STOREM, paramDt, reg1 = argReg, value = mem)
+                }
+            }
+        }
+        code += VmCodeInstruction(Opcode.CALL, labelSymbol=fcall.functionName)
+        if(fcall.type==DataType.FLOAT) {
+            if (!fcall.void && resultFpRegister != 0) {
+                // Call convention: result value is in fr0, so put it in the required register instead.
+                code += VmCodeInstruction(Opcode.LOADR, VmDataType.FLOAT, fpReg1 = resultFpRegister, fpReg2 = 0)
+            }
+        } else {
+            if (!fcall.void && resultRegister != 0) {
+                // Call convention: result value is in r0, so put it in the required register instead.
+                code += VmCodeInstruction(Opcode.LOADR, codeGen.vmType(fcall.type), reg1 = resultRegister, reg2 = 0)
+            }
+        }
+        return code
+    }
+
+}

codeGenVirtual/src/prog8/codegen/virtual/VariableAllocator.kt

@@ -0,0 +1,91 @@
+package prog8.codegen.virtual
+
+import prog8.code.SymbolTable
+import prog8.code.ast.PtProgram
+import prog8.code.core.*
+
+class VariableAllocator(private val st: SymbolTable, private val program: PtProgram, errors: IErrorReporter) {
+
+    private val allocations = mutableMapOf<List<String>, Int>()
+    private var freeMemoryStart: Int
+
+    val freeMem: Int
+        get() = freeMemoryStart
+
+    init {
+        var nextLocation = 0
+        for (variable in st.allVariables) {
+            val memsize =
+                when (variable.dt) {
+                    DataType.STR -> variable.initialStringValue!!.first.length + 1  // include the zero byte
+                    in NumericDatatypes -> program.memsizer.memorySize(variable.dt)
+                    in ArrayDatatypes -> program.memsizer.memorySize(variable.dt, variable.length!!)
+                    else -> throw InternalCompilerException("weird dt")
+                }
+
+            allocations[variable.scopedName] = nextLocation
+            nextLocation += memsize
+        }
+
+        freeMemoryStart = nextLocation
+    }
+
+    fun get(name: List<String>) = allocations.getValue(name)
+
+    fun asVmMemory(): List<Pair<List<String>, String>> {
+        val mm = mutableListOf<Pair<List<String>, String>>()
+        for (variable in st.allVariables) {
+            val location = allocations.getValue(variable.scopedName)
+            val typeStr = when(variable.dt) {
+                DataType.UBYTE, DataType.ARRAY_UB, DataType.STR -> "ubyte"
+                DataType.BYTE, DataType.ARRAY_B -> "byte"
+                DataType.UWORD, DataType.ARRAY_UW -> "uword"
+                DataType.WORD, DataType.ARRAY_W -> "word"
+                DataType.FLOAT, DataType.ARRAY_F -> "float"
+                else -> throw InternalCompilerException("weird dt")
+            }
+            val value = when(variable.dt) {
+                DataType.FLOAT -> (variable.initialNumericValue ?: 0.0).toString()
+                in NumericDatatypes -> (variable.initialNumericValue ?: 0).toHex()
+                DataType.STR -> {
+                    val encoded = program.encoding.encodeString(variable.initialStringValue!!.first, variable.initialStringValue!!.second)
+                    encoded.joinToString(",") { it.toInt().toHex() } + ",0"
+                }
+                DataType.ARRAY_F -> {
+                    if(variable.initialArrayValue!=null) {
+                        variable.initialArrayValue!!.joinToString(",") { it.number!!.toString() }
+                    } else {
+                        (1..variable.length!!).joinToString(",") { "0" }
+                    }
+                }
+                in ArrayDatatypes -> {
+                    if(variable.initialArrayValue!==null) {
+                        variable.initialArrayValue!!.joinToString(",") { it.number!!.toHex() }
+                    } else {
+                        (1..variable.length!!).joinToString(",") { "0" }
+                    }
+                }
+                else -> throw InternalCompilerException("weird dt")
+            }
+            mm.add(Pair(variable.scopedName, "$location $typeStr $value"))
+        }
+        return mm
+    }
+
+    private val memorySlabsInternal = mutableMapOf<String, Triple<UInt, UInt, UInt>>()
+    internal val memorySlabs: Map<String, Triple<UInt, UInt, UInt>> = memorySlabsInternal
+
+    fun allocateMemorySlab(name: String, size: UInt, align: UInt): UInt {
+        val address =
+            if(align==0u || align==1u)
+                freeMemoryStart.toUInt()
+            else
+                (freeMemoryStart.toUInt() + align-1u) and (0xffffffffu xor (align-1u))
+
+        memorySlabsInternal[name] = Triple(address, size, align)
+        freeMemoryStart = (address + size).toInt()
+        return address
+    }
+
+    fun getMemorySlab(name: String): Triple<UInt, UInt, UInt>? = memorySlabsInternal[name]
+}

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

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

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

@@ -1,41 +0,0 @@
-package prog8.compiler.target
-
-import com.github.michaelbull.result.fold
-import prog8.ast.base.*
-import prog8.ast.expressions.Expression
-import prog8.ast.statements.RegisterOrStatusflag
-import prog8.ast.statements.Subroutine
-import prog8.compiler.target.c64.C64MachineDefinition
-import prog8.compiler.target.cbm.Petscii
-import prog8.compiler.target.cpu6502.codegen.asmsub6502ArgsEvalOrder
-import prog8.compiler.target.cpu6502.codegen.asmsub6502ArgsHaveRegisterClobberRisk
-import prog8.compilerinterface.ICompilationTarget
-
-object C64Target: ICompilationTarget {
-    override val name = "c64"
-    override val machine = C64MachineDefinition
-    override fun encodeString(str: String, altEncoding: Boolean): List<UByte> {
-        val coded = if (altEncoding) Petscii.encodeScreencode(str, true) else Petscii.encodePetscii(str, true)
-        return coded.fold(
-            failure = { throw it },
-            success = { it }
-        )
-    }
-    override fun decodeString(bytes: List<UByte>, altEncoding: Boolean) =
-        if (altEncoding) Petscii.decodeScreencode(bytes, true) else Petscii.decodePetscii(bytes, true)
-
-    override fun asmsubArgsEvalOrder(sub: Subroutine): List<Int> =
-        asmsub6502ArgsEvalOrder(sub)
-    override fun asmsubArgsHaveRegisterClobberRisk(args: List<Expression>, paramRegisters: List<RegisterOrStatusflag>) =
-        asmsub6502ArgsHaveRegisterClobberRisk(args, paramRegisters)
-
-    override fun memorySize(dt: DataType): Int {
-        return when(dt) {
-            in ByteDatatypes -> 1
-            in WordDatatypes -> 2
-            DataType.FLOAT -> machine.FLOAT_MEM_SIZE
-            in PassByReferenceDatatypes -> machine.POINTER_MEM_SIZE
-            else -> Int.MIN_VALUE
-        }
-    }
-}

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

@@ -1,46 +0,0 @@
-package prog8.compiler.target
-
-import com.github.michaelbull.result.fold
-import prog8.ast.base.ByteDatatypes
-import prog8.ast.base.DataType
-import prog8.ast.base.PassByReferenceDatatypes
-import prog8.ast.base.WordDatatypes
-import prog8.ast.expressions.Expression
-import prog8.ast.statements.RegisterOrStatusflag
-import prog8.ast.statements.Subroutine
-import prog8.compiler.target.cbm.Petscii
-import prog8.compiler.target.cpu6502.codegen.asmsub6502ArgsEvalOrder
-import prog8.compiler.target.cpu6502.codegen.asmsub6502ArgsHaveRegisterClobberRisk
-import prog8.compiler.target.cx16.CX16MachineDefinition
-import prog8.compilerinterface.ICompilationTarget
-
-
-object Cx16Target: ICompilationTarget {
-    override val name = "cx16"
-    override val machine = CX16MachineDefinition
-    override fun encodeString(str: String, altEncoding: Boolean): List<UByte> {
-        val coded= if (altEncoding) Petscii.encodeScreencode(str, true) else Petscii.encodePetscii(str, true)
-        return coded.fold(
-            failure = { throw it },
-            success = { it }
-        )
-    }
-    override fun decodeString(bytes: List<UByte>, altEncoding: Boolean) =
-        if (altEncoding) Petscii.decodeScreencode(bytes, true) else Petscii.decodePetscii(bytes, true)
-
-    override fun asmsubArgsEvalOrder(sub: Subroutine): List<Int> =
-        asmsub6502ArgsEvalOrder(sub)
-    override fun asmsubArgsHaveRegisterClobberRisk(args: List<Expression>, paramRegisters: List<RegisterOrStatusflag>) =
-        asmsub6502ArgsHaveRegisterClobberRisk(args, paramRegisters)
-
-    override fun memorySize(dt: DataType): Int {
-        return when(dt) {
-            in ByteDatatypes -> 1
-            in WordDatatypes -> 2
-            DataType.FLOAT -> machine.FLOAT_MEM_SIZE
-            in PassByReferenceDatatypes -> machine.POINTER_MEM_SIZE
-            else -> Int.MIN_VALUE
-        }
-    }
-}
-

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

@@ -1,206 +0,0 @@
-package prog8.compiler.target.c64
-
-import prog8.compiler.target.cbm.viceMonListPostfix
-import prog8.compilerinterface.*
-import java.io.IOException
-import java.nio.file.Path
-import kotlin.math.absoluteValue
-import kotlin.math.pow
-
-object C64MachineDefinition: IMachineDefinition {
-
-    override val cpu = CpuType.CPU6502
-
-    // 5-byte cbm MFLPT format limitations:
-    override val FLOAT_MAX_POSITIVE = 1.7014118345e+38         // bytes: 255,127,255,255,255
-    override val FLOAT_MAX_NEGATIVE = -1.7014118345e+38        // bytes: 255,255,255,255,255
-    override val FLOAT_MEM_SIZE = 5
-    override val POINTER_MEM_SIZE = 2
-    override val BASIC_LOAD_ADDRESS = 0x0801u
-    override val RAW_LOAD_ADDRESS = 0xc000u
-
-    // the 2*256 byte evaluation stack (on which bytes, words, and even floats are stored during calculations)
-    override val ESTACK_LO = 0xce00u     //  $ce00-$ceff inclusive
-    override val ESTACK_HI = 0xcf00u     //  $ce00-$ceff inclusive
-
-    override lateinit var zeropage: Zeropage
-
-    override fun getFloat(num: Number) = Mflpt5.fromNumber(num)
-
-    override fun importLibs(compilerOptions: CompilationOptions, compilationTargetName: String): List<String> {
-        return if (compilerOptions.launcher == LauncherType.BASIC || compilerOptions.output == OutputType.PRG)
-            listOf("syslib")
-        else
-            emptyList()
-    }
-
-    override fun launchEmulator(selectedEmulator: Int, programNameWithPath: Path) {
-        if(selectedEmulator!=1) {
-            System.err.println("The c64 target only supports the main emulator (Vice).")
-            return
-        }
-
-        for(emulator in listOf("x64sc", "x64")) {
-            println("\nStarting C-64 emulator $emulator...")
-            val cmdline = listOf(emulator, "-silent", "-moncommands", "${programNameWithPath}.$viceMonListPostfix",
-                    "-autostartprgmode", "1", "-autostart-warp", "-autostart", "${programNameWithPath}.prg")
-            val processb = ProcessBuilder(cmdline).inheritIO()
-            val process: Process
-            try {
-                process=processb.start()
-            } catch(x: IOException) {
-                continue  // try the next emulator executable
-            }
-            process.waitFor()
-            break
-        }
-    }
-
-    override fun isIOAddress(address: UInt): Boolean = address==0u || address==1u || address in 0xd000u..0xdfffu
-
-    override fun initializeZeropage(compilerOptions: CompilationOptions) {
-        zeropage = C64Zeropage(compilerOptions)
-    }
-
-    // 6502 opcodes (including aliases and illegal opcodes), these cannot be used as variable or label names
-    override val opcodeNames = setOf("adc", "ahx", "alr", "anc", "and", "ane", "arr", "asl", "asr", "axs", "bcc", "bcs",
-            "beq", "bge", "bit", "blt", "bmi", "bne", "bpl", "brk", "bvc", "bvs", "clc",
-            "cld", "cli", "clv", "cmp", "cpx", "cpy", "dcm", "dcp", "dec", "dex", "dey",
-            "eor", "gcc", "gcs", "geq", "gge", "glt", "gmi", "gne", "gpl", "gvc", "gvs",
-            "inc", "ins", "inx", "iny", "isb", "isc", "jam", "jmp", "jsr", "lae", "las",
-            "lax", "lda", "lds", "ldx", "ldy", "lsr", "lxa", "nop", "ora", "pha", "php",
-            "pla", "plp", "rla", "rol", "ror", "rra", "rti", "rts", "sax", "sbc", "sbx",
-            "sec", "sed", "sei", "sha", "shl", "shr", "shs", "shx", "shy", "slo", "sre",
-            "sta", "stx", "sty", "tas", "tax", "tay", "tsx", "txa", "txs", "tya", "xaa")
-
-
-    class C64Zeropage(options: CompilationOptions) : Zeropage(options) {
-
-        override val SCRATCH_B1 = 0x02u      // temp storage for a single byte
-        override val SCRATCH_REG = 0x03u     // 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  $fb+$fc
-
-
-        init {
-            if (options.floats && options.zeropage !in arrayOf(ZeropageType.FLOATSAFE, ZeropageType.BASICSAFE, ZeropageType.DONTUSE ))
-                throw InternalCompilerException("when floats are enabled, zero page type should be 'floatsafe' or 'basicsafe' or 'dontuse'")
-
-            if (options.zeropage == ZeropageType.FULL) {
-                free.addAll(0x04u..0xf9u)
-                free.add(0xffu)
-                free.removeAll(setOf(0xa0u, 0xa1u, 0xa2u, 0x91u, 0xc0u, 0xc5u, 0xcbu, 0xf5u, 0xf6u))        // these are updated by IRQ
-            } else {
-                if (options.zeropage == ZeropageType.KERNALSAFE || options.zeropage == ZeropageType.FLOATSAFE) {
-                    free.addAll(listOf(
-                            0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, 0x10, 0x11,
-                            0x16, 0x17, 0x18, 0x19, 0x1a,
-                            0x1b, 0x1c, 0x1d, 0x1e, 0x1f, 0x20, 0x21,
-                            0x22, 0x23, 0x24, 0x25,
-                            0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f, 0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46,
-                            0x47, 0x48, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f, 0x51, 0x52, 0x53,
-                            0x57, 0x58, 0x59, 0x5a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f, 0x60,
-                            0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68,
-                            0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f, 0x70, 0x71, 0x72,
-                            0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 0x7a, 0x7b, 0x7c,
-                            0x7d, 0x7e, 0x7f, 0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89, 0x8a,
-                            0x8b, 0x8c, 0x8d, 0x8e, 0x8f, 0xff
-                            // 0x90-0xfa is 'kernal work storage area'
-                    ).map{it.toUInt()})
-                }
-
-                if (options.zeropage == ZeropageType.FLOATSAFE) {
-                    // remove the zeropage locations used for floating point operations from the free list
-                    free.removeAll(listOf(
-                            0x22, 0x23, 0x24, 0x25,
-                            0x10, 0x11, 0x12, 0x26, 0x27, 0x28, 0x29, 0x2a,
-                            0x57, 0x58, 0x59, 0x5a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f, 0x60,
-                            0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68,
-                            0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f, 0x70, 0x71, 0x72,
-                            0x8b, 0x8c, 0x8d, 0x8e, 0x8f, 0xff
-                    ).map{it.toUInt()})
-                }
-
-                if(options.zeropage!= ZeropageType.DONTUSE) {
-                    // add the free Zp addresses
-                    // these are valid for the C-64 but allow BASIC to keep running fully *as long as you don't use tape I/O*
-                    free.addAll(listOf(0x04, 0x05, 0x06, 0x0a, 0x0e,
-                            0x92, 0x96, 0x9b, 0x9c, 0x9e, 0x9f, 0xa5, 0xa6,
-                            0xb0, 0xb1, 0xbe, 0xbf, 0xf9).map{it.toUInt()})
-                } else {
-                    // don't use the zeropage at all
-                    free.clear()
-                }
-            }
-
-            removeReservedFromFreePool()
-        }
-    }
-
-    data class Mflpt5(val b0: UByte, val b1: UByte, val b2: UByte, val b3: UByte, val b4: UByte):
-        IMachineFloat {
-
-        companion object {
-            val zero = Mflpt5(0u, 0u, 0u, 0u, 0u)
-            fun fromNumber(num: Number): Mflpt5 {
-                // see https://en.wikipedia.org/wiki/Microsoft_Binary_Format
-                // and https://sourceforge.net/p/acme-crossass/code-0/62/tree/trunk/ACME_Lib/cbm/mflpt.a
-                // and https://en.wikipedia.org/wiki/IEEE_754-1985
-
-                val flt = num.toDouble()
-                if (flt < FLOAT_MAX_NEGATIVE || flt > FLOAT_MAX_POSITIVE)
-                    throw InternalCompilerException("floating point number out of 5-byte mflpt range: $this")
-                if (flt == 0.0)
-                    return zero
-
-                val sign = if (flt < 0.0) 0x80L else 0x00L
-                var exponent = 128 + 32    // 128 is cbm's bias, 32 is this algo's bias
-                var mantissa = flt.absoluteValue
-
-                // if mantissa is too large, shift right and adjust exponent
-                while (mantissa >= 0x100000000) {
-                    mantissa /= 2.0
-                    exponent++
-                }
-                // if mantissa is too small, shift left and adjust exponent
-                while (mantissa < 0x80000000) {
-                    mantissa *= 2.0
-                    exponent--
-                }
-
-                return when {
-                    exponent < 0 -> zero  // underflow, use zero instead
-                    exponent > 255 -> throw InternalCompilerException("floating point overflow: $this")
-                    exponent == 0 -> zero
-                    else -> {
-                        val mantLong = mantissa.toLong()
-                        Mflpt5(
-                                exponent.toUByte(),
-                                (mantLong.and(0x7f000000L) ushr 24).or(sign).toUByte(),
-                                (mantLong.and(0x00ff0000L) ushr 16).toUByte(),
-                                (mantLong.and(0x0000ff00L) ushr 8).toUByte(),
-                                (mantLong.and(0x000000ffL)).toUByte())
-                    }
-                }
-            }
-        }
-
-        override fun toDouble(): Double {
-            if (this == zero) return 0.0
-            val exp = b0.toInt() - 128
-            val sign = (b1.toInt() and 0x80) > 0
-            val number = 0x80000000L.or(b1.toLong() shl 24).or(b2.toLong() shl 16).or(b3.toLong() shl 8).or(b4.toLong())
-            val result = number.toDouble() * (2.0).pow(exp) / 0x100000000
-            return if (sign) -result else result
-        }
-
-        override fun makeFloatFillAsm(): String {
-            val b0 = "$" + b0.toString(16).padStart(2, '0')
-            val b1 = "$" + b1.toString(16).padStart(2, '0')
-            val b2 = "$" + b2.toString(16).padStart(2, '0')
-            val b3 = "$" + b3.toString(16).padStart(2, '0')
-            val b4 = "$" + b4.toString(16).padStart(2, '0')
-            return "$b0, $b1, $b2, $b3, $b4"
-        }
-    }
-}

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

@@ -1,103 +0,0 @@
-package prog8.compiler.target.cbm
-
-import com.github.michaelbull.result.Ok
-import com.github.michaelbull.result.Result
-import com.github.michaelbull.result.mapError
-import prog8.compilerinterface.CompilationOptions
-import prog8.compilerinterface.IAssemblyProgram
-import prog8.compilerinterface.OutputType
-import prog8.compilerinterface.generatedLabelPrefix
-import prog8.parser.SourceCode
-import java.io.File
-import java.nio.file.Path
-import kotlin.io.path.Path
-import kotlin.io.path.isRegularFile
-
-
-internal const val viceMonListPostfix = "vice-mon-list"
-
-class AssemblyProgram(
-        override val valid: Boolean,
-        override val name: String,
-        outputDir: Path,
-        private val compTarget: String) : IAssemblyProgram {
-
-    private val assemblyFile = outputDir.resolve("$name.asm")
-    private val prgFile = outputDir.resolve("$name.prg")
-    private val binFile = outputDir.resolve("$name.bin")
-    private val viceMonListFile = outputDir.resolve("$name.$viceMonListPostfix")
-
-    override fun assemble(quiet: Boolean, options: CompilationOptions): Int {
-        // add "-Wlong-branch"  to see warnings about conversion of branch instructions to jumps (default = do this silently)
-        val command = mutableListOf("64tass", "--ascii", "--case-sensitive", "--long-branch",
-                "-Wall", "-Wno-strict-bool", "-Wno-shadow", // "-Werror",
-                "--dump-labels", "--vice-labels", "-l", viceMonListFile.toString(), "--no-monitor")
-
-        if(quiet)
-            command.add("--quiet")
-
-        val outFile = when (options.output) {
-            OutputType.PRG -> {
-                command.add("--cbm-prg")
-                println("\nCreating prg for target $compTarget.")
-                prgFile
-            }
-            OutputType.RAW -> {
-                command.add("--nostart")
-                println("\nCreating raw binary for target $compTarget.")
-                binFile
-            }
-        }
-        command.addAll(listOf("--output", outFile.toString(), assemblyFile.toString()))
-
-        val proc = ProcessBuilder(command).inheritIO().start()
-        val result = proc.waitFor()
-        if (result == 0) {
-            removeGeneratedLabelsFromMonlist()
-            generateBreakpointList()
-        }
-        return result
-    }
-
-    private fun removeGeneratedLabelsFromMonlist() {
-        val pattern = Regex("""al (\w+) \S+${generatedLabelPrefix}.+?""")
-        val lines = viceMonListFile.toFile().readLines()
-        viceMonListFile.toFile().outputStream().bufferedWriter().use {
-            for (line in lines) {
-                if(pattern.matchEntire(line)==null)
-                    it.write(line+"\n")
-            }
-        }
-    }
-
-    private fun generateBreakpointList() {
-        // builds list of breakpoints, appends to monitor list file
-        val breakpoints = mutableListOf<String>()
-        val pattern = Regex("""al (\w+) \S+_prog8_breakpoint_\d+.?""")      // gather breakpoints by the source label that's generated for them
-        for (line in viceMonListFile.toFile().readLines()) {
-            val match = pattern.matchEntire(line)
-            if (match != null)
-                breakpoints.add("break \$" + match.groupValues[1])
-        }
-        val num = breakpoints.size
-        breakpoints.add(0, "; vice monitor breakpoint list now follows")
-        breakpoints.add(1, "; $num breakpoints have been defined")
-        breakpoints.add(2, "del")
-        viceMonListFile.toFile().appendText(breakpoints.joinToString("\n") + "\n")
-    }
-}
-
-
-internal fun loadAsmIncludeFile(filename: String, source: SourceCode): Result<String, NoSuchFileException> {
-    return if (filename.startsWith(SourceCode.libraryFilePrefix)) {
-        return com.github.michaelbull.result.runCatching {
-            SourceCode.Resource("/prog8lib/${filename.substring(SourceCode.libraryFilePrefix.length)}").readText()
-        }.mapError { NoSuchFileException(File(filename)) }
-    } else {
-        val sib = Path(source.origin).resolveSibling(filename)
-        if (sib.isRegularFile())
-            Ok(SourceCode.File(sib).readText())
-        else
-            Ok(SourceCode.File(Path(filename)).readText())
-    }
-}

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

@@ -1,124 +0,0 @@
-package prog8.compiler.target.cx16
-
-import prog8.compiler.target.c64.C64MachineDefinition
-import prog8.compiler.target.cbm.viceMonListPostfix
-import prog8.compilerinterface.*
-import java.io.IOException
-import java.nio.file.Path
-
-
-object CX16MachineDefinition: IMachineDefinition {
-
-    override val cpu = CpuType.CPU65c02
-
-    // 5-byte cbm MFLPT format limitations:
-    override val FLOAT_MAX_POSITIVE = 1.7014118345e+38         // bytes: 255,127,255,255,255
-    override val FLOAT_MAX_NEGATIVE = -1.7014118345e+38        // bytes: 255,255,255,255,255
-    override val FLOAT_MEM_SIZE = 5
-    override val POINTER_MEM_SIZE = 2
-    override val BASIC_LOAD_ADDRESS = 0x0801u
-    override val RAW_LOAD_ADDRESS = 0x8000u
-
-    // the 2*256 byte evaluation stack (on which bytes, words, and even floats are stored during calculations)
-    override val ESTACK_LO = 0x0400u        //  $0400-$04ff inclusive
-    override val ESTACK_HI = 0x0500u        //  $0500-$05ff inclusive
-
-    override lateinit var zeropage: Zeropage
-
-    override fun getFloat(num: Number) = C64MachineDefinition.Mflpt5.fromNumber(num)
-    override fun importLibs(compilerOptions: CompilationOptions, compilationTargetName: String): List<String> {
-        return if (compilerOptions.launcher == LauncherType.BASIC || compilerOptions.output == OutputType.PRG)
-            listOf("syslib")
-        else
-            emptyList()
-    }
-
-    override fun launchEmulator(selectedEmulator: Int, programNameWithPath: Path) {
-        val emulatorName: String
-        val extraArgs: List<String>
-
-        when(selectedEmulator) {
-            1 -> {
-                emulatorName = "x16emu"
-                extraArgs = emptyList()
-            }
-            2 -> {
-                emulatorName = "box16"
-                extraArgs = listOf("-sym", "${programNameWithPath}.$viceMonListPostfix")
-            }
-            else -> {
-                System.err.println("Cx16 target only supports x16emu and box16 emulators.")
-                return
-            }
-        }
-
-        for(emulator in listOf(emulatorName)) {
-            println("\nStarting Commander X16 emulator $emulator...")
-            val cmdline = listOf(emulator, "-scale", "2", "-run", "-prg", "${programNameWithPath}.prg") + extraArgs
-            val processb = ProcessBuilder(cmdline).inheritIO()
-            val process: Process
-            try {
-                process=processb.start()
-            } catch(x: IOException) {
-                continue  // try the next emulator executable
-            }
-            process.waitFor()
-            break
-        }
-    }
-
-    override fun isIOAddress(address: UInt): Boolean = address==0u || address==1u || address in 0x9f00u..0x9fffu
-
-    override fun initializeZeropage(compilerOptions: CompilationOptions) {
-        zeropage = CX16Zeropage(compilerOptions)
-    }
-
-    // 6502 opcodes (including aliases and illegal opcodes), these cannot be used as variable or label names
-    override val opcodeNames = setOf("adc", "and", "asl", "bcc", "bcs",
-            "beq", "bge", "bit", "blt", "bmi", "bne", "bpl", "brk", "bvc", "bvs", "clc",
-            "cld", "cli", "clv", "cmp", "cpx", "cpy", "dec", "dex", "dey",
-            "eor", "gcc", "gcs", "geq", "gge", "glt", "gmi", "gne", "gpl", "gvc", "gvs",
-            "inc", "inx", "iny", "jmp", "jsr",
-            "lda", "ldx", "ldy", "lsr", "nop", "ora", "pha", "php",
-            "pla", "plp", "rol", "ror", "rti", "rts", "sbc",
-            "sec", "sed", "sei",
-            "sta", "stx", "sty", "tax", "tay", "tsx", "txa", "txs", "tya",
-            "bra", "phx", "phy", "plx", "ply", "stz", "trb", "tsb", "bbr", "bbs",
-            "rmb", "smb", "stp", "wai")
-
-
-    class CX16Zeropage(options: CompilationOptions) : Zeropage(options) {
-
-        override val SCRATCH_B1 = 0x7au      // temp storage for a single byte
-        override val SCRATCH_REG = 0x7bu     // temp storage for a register, must be B1+1
-        override val SCRATCH_W1 = 0x7cu      // temp storage 1 for a word  $7c+$7d
-        override val SCRATCH_W2 = 0x7eu      // temp storage 2 for a word  $7e+$7f
-
-
-        init {
-            if (options.floats && options.zeropage !in arrayOf(ZeropageType.BASICSAFE, ZeropageType.DONTUSE ))
-                throw InternalCompilerException("when floats are enabled, zero page type should be 'basicsafe' or 'dontuse'")
-
-            // the addresses 0x02 to 0x21 (inclusive) are taken for sixteen virtual 16-bit api registers.
-
-            when (options.zeropage) {
-                ZeropageType.FULL -> {
-                    free.addAll(0x22u..0xffu)
-                }
-                ZeropageType.KERNALSAFE -> {
-                    free.addAll(0x22u..0x7fu)
-                    free.addAll(0xa9u..0xffu)
-                }
-                ZeropageType.BASICSAFE -> {
-                    free.addAll(0x22u..0x7fu)
-                }
-                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}")
-            }
-
-            removeReservedFromFreePool()
-        }
-    }
-}

codeGeneration/test/ProjectConfig.kt

@@ -1,8 +0,0 @@
-package prog8tests.asmgen
-
-import io.kotest.core.config.AbstractProjectConfig
-import kotlin.math.max
-
-object ProjectConfig : AbstractProjectConfig() {
-    override val parallelism = max(2, Runtime.getRuntime().availableProcessors() / 2)
-}

codeGeneration/test/helpers/Dummies.kt

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