tweaks

this makes $02-$21 inclusive, available for use later (x16 virtual registers are placed here on x16...)

.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/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/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:5.3.2" />
     <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/5.3.2/kotest-assertions-core-jvm-5.3.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk8/1.6.21/kotlin-stdlib-jdk8-1.6.21.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/1.6.21/kotlin-stdlib-1.6.21.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/annotations/13.0/annotations-13.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk7/1.5.0/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-jdk7/1.6.21/kotlin-stdlib-jdk7-1.6.21.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-shared-jvm/5.3.2/kotest-assertions-shared-jvm-5.3.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/github/java-diff-utils/java-diff-utils/4.11/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-jdk8/1.6.1/kotlinx-coroutines-jdk8-1.6.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-reflect/1.6.21/kotlin-reflect-1.6.21.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-core-jvm/1.6.1/kotlinx-coroutines-core-jvm-1.6.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-common/1.6.0/kotlin-stdlib-common-1.6.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-common-jvm/5.3.2/kotest-common-jvm-5.3.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-api-jvm/5.3.2/kotest-assertions-api-jvm-5.3.2.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:5.3.2" />
     <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/5.3.2/kotest-property-jvm-5.3.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/com/github/curious-odd-man/rgxgen/1.3/rgxgen-1.3.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk8/1.6.21/kotlin-stdlib-jdk8-1.6.21.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/1.6.21/kotlin-stdlib-1.6.21.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/annotations/13.0/annotations-13.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk7/1.5.0/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-jdk7/1.6.21/kotlin-stdlib-jdk7-1.6.21.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-common-jvm/5.3.2/kotest-common-jvm-5.3.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-shared-jvm/5.3.2/kotest-assertions-shared-jvm-5.3.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-api-jvm/5.3.2/kotest-assertions-api-jvm-5.3.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-jdk8/1.6.1/kotlinx-coroutines-jdk8-1.6.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/opentest4j/opentest4j/1.2.0/opentest4j-1.2.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/github/java-diff-utils/java-diff-utils/4.11/java-diff-utils-4.11.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-reflect/1.6.21/kotlin-reflect-1.6.21.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-core-jvm/1.6.1/kotlinx-coroutines-core-jvm-1.6.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-common/1.6.0/kotlin-stdlib-common-1.6.0.jar!/" />
     </CLASSES>
     <JAVADOC />
     <SOURCES />

.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:5.3.2" />
     <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/5.3.2/kotest-runner-junit5-jvm-5.3.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-framework-api-jvm/5.3.2/kotest-framework-api-jvm-5.3.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-shared-jvm/5.3.2/kotest-assertions-shared-jvm-5.3.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/github/java-diff-utils/java-diff-utils/4.11/java-diff-utils-4.11.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-test-jvm/1.6.1/kotlinx-coroutines-test-jvm-1.6.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-common-jvm/5.3.2/kotest-common-jvm-5.3.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-framework-engine-jvm/5.3.2/kotest-framework-engine-jvm-5.3.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/github/classgraph/classgraph/4.8.146/classgraph-4.8.146.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/com/github/ajalt/mordant/1.2.1/mordant-1.2.1.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/com/github/ajalt/colormath/1.2.0/colormath-1.2.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-script-util/1.5.0/kotlin-script-util-1.5.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/intellij/deps/trove4j/1.0.20181211/trove4j-1.0.20181211.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-daemon-client/1.5.0/kotlin-daemon-client-1.5.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-core/1.3.8/kotlinx-coroutines-core-1.3.8.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-scripting-jvm/1.5.0/kotlin-scripting-jvm-1.5.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-scripting-common/1.5.0/kotlin-scripting-common-1.5.0.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/opentest4j/opentest4j/1.2.0/opentest4j-1.2.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-framework-discovery-jvm/4.6.3/kotest-framework-discovery-jvm-4.6.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-core-jvm/4.6.3/kotest-assertions-core-jvm-4.6.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-jdk8/1.5.0/kotlinx-coroutines-jdk8-1.5.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-api-jvm/4.6.3/kotest-assertions-api-jvm-4.6.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-extensions-jvm/4.6.3/kotest-extensions-jvm-4.6.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/commons-io/commons-io/2.6/commons-io-2.6.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/mockk/mockk/1.9.3/mockk-1.9.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/mockk/mockk-common/1.9.3/mockk-common-1.9.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/mockk/mockk-dsl/1.9.3/mockk-dsl-1.9.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/mockk/mockk-dsl-jvm/1.9.3/mockk-dsl-jvm-1.9.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/mockk/mockk-agent-jvm/1.9.3/mockk-agent-jvm-1.9.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/mockk/mockk-agent-api/1.9.3/mockk-agent-api-1.9.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/mockk/mockk-agent-common/1.9.3/mockk-agent-common-1.9.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/objenesis/objenesis/3.0.1/objenesis-3.0.1.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/net/bytebuddy/byte-buddy/1.9.10/byte-buddy-1.9.10.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/net/bytebuddy/byte-buddy-agent/1.9.10/byte-buddy-agent-1.9.10.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-framework-concurrency-jvm/4.6.3/kotest-framework-concurrency-jvm-4.6.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-core-jvm/1.5.0/kotlinx-coroutines-core-jvm-1.5.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-common/1.5.0/kotlin-stdlib-common-1.5.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/junit/platform/junit-platform-engine/1.6.2/junit-platform-engine-1.6.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-debug/1.6.1/kotlinx-coroutines-debug-1.6.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/net/java/dev/jna/jna/5.9.0/jna-5.9.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/net/java/dev/jna/jna-platform/5.9.0/jna-platform-5.9.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-framework-discovery-jvm/5.3.2/kotest-framework-discovery-jvm-5.3.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-core-jvm/5.3.2/kotest-assertions-core-jvm-5.3.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-jdk8/1.6.1/kotlinx-coroutines-jdk8-1.6.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-api-jvm/5.3.2/kotest-assertions-api-jvm-5.3.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-extensions-jvm/5.3.2/kotest-extensions-jvm-5.3.2.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/1.12.3/mockk-1.12.3.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/mockk/mockk-common/1.12.3/mockk-common-1.12.3.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/mockk/mockk-dsl/1.12.3/mockk-dsl-1.12.3.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/mockk/mockk-dsl-jvm/1.12.3/mockk-dsl-jvm-1.12.3.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/mockk/mockk-agent-jvm/1.12.3/mockk-agent-jvm-1.12.3.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/mockk/mockk-agent-api/1.12.3/mockk-agent-api-1.12.3.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/mockk/mockk-agent-common/1.12.3/mockk-agent-common-1.12.3.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/objenesis/objenesis/3.1/objenesis-3.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/net/bytebuddy/byte-buddy/1.12.6/byte-buddy-1.12.6.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/net/bytebuddy/byte-buddy-agent/1.12.6/byte-buddy-agent-1.12.6.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-framework-concurrency-jvm/5.3.2/kotest-framework-concurrency-jvm-5.3.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-core-jvm/1.6.1/kotlinx-coroutines-core-jvm-1.6.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-common/1.6.0/kotlin-stdlib-common-1.6.0.jar!/" />
+      <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-jdk8/1.6.21/kotlin-stdlib-jdk8-1.6.21.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/1.6.21/kotlin-stdlib-1.6.21.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/annotations/13.0/annotations-13.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk7/1.5.0/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-jdk7/1.6.21/kotlin-stdlib-jdk7-1.6.21.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-reflect/1.6.21/kotlin-reflect-1.6.21.jar!/" />
     </CLASSES>
     <JAVADOC />
     <SOURCES />

.idea/libraries/jetbrains_kotlinx_cli_jvm.xml

@@ -1,8 +1,8 @@
 <component name="libraryTable">
   <library name="jetbrains.kotlinx.cli.jvm" type="repository">
-    <properties include-transitive-deps="false" maven-id="org.jetbrains.kotlinx:kotlinx-cli-jvm:0.3.3" />
+    <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/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:1.1.16" />
     <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/1.1.16/kotlin-result-jvm-1.1.16.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-common/1.6.20/kotlin-stdlib-common-1.6.20.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk8/1.6.20/kotlin-stdlib-jdk8-1.6.20.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/1.6.20/kotlin-stdlib-1.6.20.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/annotations/13.0/annotations-13.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk7/1.5.10/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-jdk7/1.6.20/kotlin-stdlib-jdk7-1.6.20.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/libraries/takes.xml

@@ -1,11 +1,15 @@
 <component name="libraryTable">
   <library name="takes" type="repository">
-    <properties maven-id="org.takes:takes:1.19" />
+    <properties maven-id="org.takes:takes:1.20" />
     <CLASSES>
-      <root url="jar://$MAVEN_REPOSITORY$/org/takes/takes/1.19/takes-1.19.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/cactoos/cactoos/0.42/cactoos-0.42.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/takes/takes/1.20/takes-1.20.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/cactoos/cactoos/0.50/cactoos-0.50.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/javax/xml/bind/jaxb-api/2.3.0/jaxb-api-2.3.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/slf4j/slf4j-api/1.7.25/slf4j-api-1.7.25.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/apache/commons/commons-text/1.4/commons-text-1.4.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/apache/commons/commons-lang3/3.7/commons-lang3-3.7.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/com/sun/xml/bind/jaxb-core/2.3.0/jaxb-core-2.3.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/com/sun/xml/bind/jaxb-impl/2.3.0/jaxb-impl-2.3.0.jar!/" />
     </CLASSES>
     <JAVADOC />
     <SOURCES />

.idea/modules.xml

@@ -2,18 +2,20 @@
 <project version="4">
   <component name="ProjectModuleManager">
     <modules>
+      <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://$PROJECT_DIR$/codeGenExperimental6502/codeGenExperimental6502.iml" filepath="$PROJECT_DIR$/codeGenExperimental6502/codeGenExperimental6502.iml" />
-      <module fileurl="file://$PROJECT_DIR$/codeGenTargets/codeGenTargets.iml" filepath="$PROJECT_DIR$/codeGenTargets/codeGenTargets.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>

LICENSE

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

README.md

@@ -16,10 +16,11 @@ https://prog8.readthedocs.io/
 
 Software license
 ----------------
-GNU GPL 3.0, see file LICENSE
+GNU GPL 3.0 (see file LICENSE), with exception for generated code:
 
-- prog8 (the compiler + libraries) is licensed under GNU GPL 3.0
-- *exception:* the resulting files created by running the compiler are free to use in whatever way desired.
+- The compiler and its libraries are free to use according to the terms of the GNU GPL 3.0
+- *exception:* the resulting files (intermediate source codes and resulting binary program) created by the compiler
+  are excluded from the GPL and are free to use in whatever way desired, commercially or not.
 
 
 What does Prog8 provide?

codeAst/build.gradle

@@ -24,12 +24,8 @@ compileTestKotlin {
 }
 
 dependencies {
-    implementation project(':compilerInterfaces')
-    implementation project(':compilerAst')
+    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:1.1.12"
-
 }
 
 sourceSets {

codeAst/codeAst.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="module" module-name="codeCore" />
+  </component>
+</module>

codeAst/src/prog8/code/SymbolTable.kt

@@ -0,0 +1,235 @@
+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
+    }
+
+    val allMemMappedVariables: Collection<StMemVar> by lazy {
+        val vars = mutableListOf<StMemVar>()
+        fun collect(node: StNode) {
+            for(child in node.children) {
+                if(child.value.type== StNodeType.MEMVAR)
+                    vars.add(child.value as StMemVar)
+                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=$value")
+    }
+}
+
+
+class StMemVar(name: String,
+               val dt: DataType,
+               val address: UInt,
+               val length: Int?,             // for arrays: the number of elements, for strings: number of characters *including* the terminating 0-byte
+               position: Position) :
+    StNode(name, StNodeType.MEMVAR, position) {
+    override fun printProperties() {
+        print("$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 +1,218 @@
+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) {
+
+    init {
+        if(type==DataType.BOOL)
+            throw IllegalArgumentException("bool should have become ubyte @$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) {
+    // note: "and", "or", "xor" do not occur anymore as operators. They've been replaced int the ast by their bitwise versions &, |, ^.
+    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  $type")
+    }
+}
+
+
+class PtMemoryByte(position: Position) : PtExpression(DataType.UBYTE, position) {
+    val address: PtExpression
+        get() = children.single() as PtExpression
+    override fun printProperties() {}
+}
+
+
+class PtNumber(type: DataType, val number: Double, position: Position) : PtExpression(type, position) {
+
+    init {
+        if(type==DataType.BOOL)
+            throw IllegalArgumentException("bool should have become ubyte @$position")
+        if(type!=DataType.FLOAT) {
+            val rounded = round(number)
+            if (rounded != number)
+                throw IllegalArgumentException("refused rounding of float to avoid loss of precision @$position")
+        }
+    }
+
+    override fun printProperties() {
+        print("$number ($type)")
+    }
+
+    override fun hashCode(): Int = Objects.hash(type, number)
+
+    override fun equals(other: Any?): Boolean {
+        if(other==null || other !is PtNumber)
+            return false
+        return number==other.number
+    }
+
+    operator fun compareTo(other: PtNumber): Int = number.compareTo(other.number)
+}
+
+
+class PtPrefix(val operator: String, type: DataType, position: Position): PtExpression(type, position) {
+    val value: PtExpression
+        get() = children.single() as PtExpression
+
+    init {
+        // note: the "not" operator may no longer occur in the ast; not x should have been replaced with x==0
+        if(operator !in setOf("+", "-", "~"))
+            throw IllegalArgumentException("invalid prefix operator: $operator")
+    }
+
+    override fun printProperties() {
+        print(operator)
+    }
+}
+
+
+class PtRange(type: DataType, position: Position) : PtExpression(type, position) {
+    val from: PtExpression
+        get() = children[0] as PtExpression
+    val to: PtExpression
+        get() = children[1] as PtExpression
+    val step: PtNumber
+        get() = children[2] as PtNumber
+
+    override fun printProperties() {}
+}
+
+
+class PtString(val value: String, val encoding: Encoding, position: Position) : PtExpression(DataType.STR, position) {
+    override fun printProperties() {
+        print("$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

@@ -24,12 +24,9 @@ compileTestKotlin {
 }
 
 dependencies {
-    implementation project(':compilerInterfaces')
-    implementation project(':compilerAst')
+    // should have no dependencies to other modules
     implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8"
-    // implementation "org.jetbrains.kotlin:kotlin-reflect"
-    implementation "com.michael-bull.kotlin-result:kotlin-result-jvm:1.1.12"
-
+    implementation "com.michael-bull.kotlin-result:kotlin-result-jvm:1.1.16"
 }
 
 sourceSets {

codeCore/codeCore.iml

@@ -10,7 +10,5 @@
     <orderEntry type="sourceFolder" forTests="false" />
     <orderEntry type="library" name="KotlinJavaRuntime" level="project" />
     <orderEntry type="library" name="michael.bull.kotlin.result.jvm" level="project" />
-    <orderEntry type="module" module-name="compilerInterfaces" />
-    <orderEntry type="module" module-name="compilerAst" />
   </component>
 </module>

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

@@ -1,34 +1,18 @@
-package prog8.compilerinterface
+package prog8.code.core
 
 import java.nio.file.Path
 import kotlin.io.path.Path
 
-enum class OutputType {
-    RAW,
-    PRG
-}
-
-enum class LauncherType {
-    BASIC,
-    NONE
-}
-
-enum class ZeropageType {
-    BASICSAFE,
-    FLOATSAFE,
-    KERNALSAFE,
-    FULL,
-    DONTUSE
-}
 
 class CompilationOptions(val output: OutputType,
-                         val launcher: LauncherType,
+                         val launcher: CbmPrgLauncherType,
                          val zeropage: ZeropageType,
                          val zpReserved: List<UIntRange>,
                          val floats: Boolean,
                          val noSysInit: Boolean,
                          val compTarget: ICompilationTarget,
-                         // these are set based on command line arguments:
+                         // 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,
@@ -36,6 +20,7 @@ class CompilationOptions(val output: OutputType,
                          var asmQuiet: Boolean = false,
                          var asmListfile: Boolean = false,
                          var experimentalCodegen: Boolean = false,
-                         var outputDir: Path = Path("")
-) {
-}
+                         var evalStackBaseAddress: UInt? = null,
+                         var outputDir: Path = Path(""),
+                         var symbolDefs: Map<String, String> = emptyMap()
+)

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
+    BOOL,               // 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
+    ARRAY_BOOL,         // 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) {
+            BOOL -> targetType.oneOf(BOOL, BYTE, UBYTE, WORD, UWORD, FLOAT)
+            UBYTE -> targetType.oneOf(UBYTE, WORD, UWORD, FLOAT, BOOL)
+            BYTE -> targetType.oneOf(BYTE, WORD, FLOAT)
+            UWORD -> targetType.oneOf(UWORD, FLOAT)
+            WORD -> targetType.oneOf(WORD, FLOAT)
+            FLOAT -> targetType.oneOf(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
+}
+
+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, DataType.BOOL)
+val WordDatatypes = arrayOf(DataType.UWORD, DataType.WORD)
+val IntegerDatatypes = arrayOf(DataType.UBYTE, DataType.BYTE, DataType.UWORD, DataType.WORD, DataType.BOOL)
+val IntegerDatatypesNoBool = arrayOf(DataType.UBYTE, DataType.BYTE, DataType.UWORD, DataType.WORD)
+val NumericDatatypes = arrayOf(DataType.UBYTE, DataType.BYTE, DataType.UWORD, DataType.WORD, DataType.FLOAT, DataType.BOOL)
+val NumericDatatypesNoBool = arrayOf(DataType.UBYTE, DataType.BYTE, DataType.UWORD, DataType.WORD, DataType.FLOAT)
+val SignedDatatypes =  arrayOf(DataType.BYTE, DataType.WORD, DataType.FLOAT)
+val ArrayDatatypes = arrayOf(DataType.ARRAY_UB, DataType.ARRAY_B, DataType.ARRAY_UW, DataType.ARRAY_W, DataType.ARRAY_F, DataType.ARRAY_BOOL)
+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, DataType.ARRAY_BOOL
+)
+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,
+    DataType.ARRAY_BOOL to DataType.BOOL
+)
+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,
+    DataType.BOOL to DataType.ARRAY_BOOL
+)
+val Cx16VirtualRegisters = arrayOf(
+    RegisterOrPair.R0, RegisterOrPair.R1, RegisterOrPair.R2, RegisterOrPair.R3,
+    RegisterOrPair.R4, RegisterOrPair.R5, RegisterOrPair.R6, RegisterOrPair.R7,
+    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

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

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

@@ -1,5 +1,4 @@
-package prog8.compilerinterface
-
+package prog8.code.core
 
 interface IAssemblyGenerator {
     fun compileToAssembly(): IAssemblyProgram?

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
 
@@ -10,17 +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 ESTACK_LO: UInt
-    val ESTACK_HI: UInt
-    val BASIC_LOAD_ADDRESS : UInt
-    val RAW_LOAD_ADDRESS : UInt
+    var ESTACK_LO: UInt
+    var ESTACK_HI: UInt
+    val PROGRAM_LOAD_ADDRESS : UInt
 
     val opcodeNames: Set<String>
     var zeropage: Zeropage
@@ -32,4 +32,9 @@ interface IMachineDefinition {
     fun importLibs(compilerOptions: CompilationOptions, compilationTargetName: String): List<String>
     fun launchEmulator(selectedEmulator: Int, programNameWithPath: Path)
     fun isIOAddress(address: UInt): Boolean
+    fun overrideEvalStack(evalStackBaseAddress: UInt) {
+        require(evalStackBaseAddress and 255u == 0u)
+        ESTACK_LO = evalStackBaseAddress
+        ESTACK_HI = evalStackBaseAddress + 256u
+    }
 }

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 +1,19 @@
+package prog8.code.core
+
+val AssociativeOperators = setOf("+", "*", "&", "|", "^", "==", "!=")
+val ComparisonOperators = setOf("==", "!=", "<", ">", "<=", ">=")
+val LogicalOperators = setOf("and", "or", "xor", "not")
+val AugmentAssignmentOperators = setOf("+", "-", "/", "*", "&", "|", "^", "<<", ">>", "%")
+val BitwiseOperators = setOf("&", "|", "^", "~")
+// val InvalidOperatorsForBoolean = setOf("+", "-", "*", "/", "%", "<<", ">>") + BitwiseOperators
+
+fun invertedComparisonOperator(operator: String) =
+    when (operator) {
+        "==" -> "!="
+        "!=" -> "=="
+        "<" -> ">="
+        ">" -> "<="
+        "<=" -> ">"
+        ">=" -> "<"
+        else -> null
+    }

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

@@ -0,0 +1,22 @@
+package prog8.code.core
+
+import java.nio.file.InvalidPathException
+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 {
+        return try {
+            val path = Path(file).absolute().normalize().toString()
+            "file://$path:$line:$startCol:"
+        } catch(x: InvalidPathException) {
+            // this can occur on Windows when the source origin contains "invalid" characters such as ':'
+            "file://$file:$line:$startCol:"
+        }
+    }
+
+    companion object {
+        val DUMMY = Position("~dummy~", 0, 0, 0)
+    }
+}

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

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

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

@@ -1,4 +1,4 @@
-package prog8.parser
+package prog8.code.core
 
 import java.io.File
 import java.io.IOException
@@ -6,6 +6,10 @@ import java.nio.file.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].
  */
@@ -30,7 +34,7 @@ sealed class SourceCode {
      * Where this [SourceCode] instance came from.
      * This can be one of the following:
      * * a normal string representation of a [java.nio.file.Path], if it originates from a file (see [File])
-     * * `$stringSourcePrefix44c56085>` if was created via [String]
+     * * `string:44c56085` if was created via [String]
      * * `library:/x/y/z.ext` if it is a library file that was loaded from resources (see [Resource])
      */
     abstract val origin: String
@@ -51,7 +55,7 @@ sealed class SourceCode {
          * filename prefix to designate library files that will be retreived from internal resources rather than disk
          */
         const val libraryFilePrefix = "library:"
-        const val stringSourcePrefix = "<String@"
+        const val stringSourcePrefix = "string:"
         val curdir: Path = Path(".").toAbsolutePath()
         fun relative(path: Path): Path = curdir.relativize(path.toAbsolutePath())
         fun isRegularFilesystemPath(pathString: String) =
@@ -60,12 +64,12 @@ sealed class SourceCode {
 
     /**
      * Turn a plain String into a [SourceCode] object.
-     * [origin] will be something like `$stringSourcePrefix44c56085>`.
+     * [origin] will be something like `string:44c56085`.
      */
     class Text(override val text: String): SourceCode() {
         override val isFromResources = false
         override val isFromFilesystem = false
-        override val origin = "$stringSourcePrefix${System.identityHashCode(text).toString(16)}>"
+        override val origin = "$stringSourcePrefix${System.identityHashCode(text).toString(16)}"
         override val name = "<unnamed-text>"
     }
 
@@ -128,11 +132,10 @@ sealed class SourceCode {
     /**
      * SourceCode for internally generated nodes (usually Modules)
      */
-    class Generated(name: String) : SourceCode() {
+    class Generated(override val name: String) : SourceCode() {
         override val isFromResources: Boolean = false
         override val isFromFilesystem: Boolean = false
         override val origin: String = name
-        override val name: String = name
         override val text: String = "<generated code node, no text representation>"
     }
 }

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

@@ -1,13 +1,8 @@
-package prog8.compilerinterface
+package prog8.code.core
 
 import com.github.michaelbull.result.Err
 import com.github.michaelbull.result.Ok
 import com.github.michaelbull.result.Result
-import prog8.ast.INameScope
-import prog8.ast.base.*
-import prog8.ast.expressions.ArrayLiteral
-import prog8.ast.expressions.Expression
-import prog8.ast.expressions.StringLiteral
 
 
 class ZeropageAllocationError(message: String) : Exception(message)
@@ -20,12 +15,7 @@ abstract class Zeropage(protected val options: CompilationOptions) {
     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,
-                            val originalScope: INameScope,
-                            val initialStringValue: StringLiteral?,
-                            val initialArrayValue: ArrayLiteral?)
+    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)
@@ -53,11 +43,10 @@ abstract class Zeropage(protected val options: CompilationOptions) {
 
     fun allocate(name: List<String>,
                  datatype: DataType,
-                 originalScope: INameScope,
                  numElements: Int?,
-                 initValue: Expression?,
                  position: Position?,
-                 errors: IErrorReporter): Result<Pair<UInt, Int>, ZeropageAllocationError> {
+                 errors: IErrorReporter
+    ): Result<Pair<UInt, Int>, ZeropageAllocationError> {
 
         require(name.isEmpty() || name !in allocatedVariables) {"name can't be allocated twice"}
 
@@ -68,7 +57,7 @@ abstract class Zeropage(protected val options: CompilationOptions) {
                 when (datatype) {
                     in IntegerDatatypes -> options.compTarget.memorySize(datatype)
                     DataType.STR, in ArrayDatatypes  -> {
-                        val memsize = numElements!! * options.compTarget.memorySize(ArrayToElementTypes.getValue(datatype))
+                        val memsize = options.compTarget.memorySize(datatype, numElements!!)
                         if(position!=null)
                             errors.warn("allocating a large value in zeropage; str/array $memsize bytes", position)
                         else
@@ -93,13 +82,13 @@ abstract class Zeropage(protected val options: CompilationOptions) {
                 if(size==1) {
                     for(candidate in free.minOrNull()!! .. free.maxOrNull()!!+1u) {
                         if(oneSeparateByteFree(candidate))
-                            return Ok(Pair(makeAllocation(candidate, 1, datatype, name, initValue, originalScope), 1))
+                            return Ok(Pair(makeAllocation(candidate, 1, datatype, name), 1))
                     }
-                    return Ok(Pair(makeAllocation(free[0], 1, datatype, name, initValue, originalScope), 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, initValue, originalScope), size))
+                        return Ok(Pair(makeAllocation(candidate, size, datatype, name), size))
                 }
             }
         }
@@ -109,14 +98,14 @@ abstract class Zeropage(protected val options: CompilationOptions) {
 
     private fun reserve(range: UIntRange) = free.removeAll(range)
 
-    private fun makeAllocation(address: UInt, size: Int, datatype: DataType, name: List<String>, initValue: Expression?, originalScope: INameScope): UInt {
+    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, originalScope, null, null)        // numerical variables in zeropage never have an initial value here because they are set in separate initializer assignments
-                DataType.STR -> ZpAllocation(address, datatype, size, originalScope, initValue as? StringLiteral, null)
-                in ArrayDatatypes -> ZpAllocation(address, datatype, size, originalScope, null, initValue as? ArrayLiteral)
+                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")
             }
         }

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

@@ -1,31 +1,35 @@
-package prog8.codegen.target
+package prog8.code.target
 
 import com.github.michaelbull.result.fold
-import prog8.ast.base.FatalAstException
-import prog8.codegen.target.cbm.IsoEncoding
-import prog8.codegen.target.cbm.PetsciiEncoding
-import prog8.compilerinterface.Encoding
-import prog8.compilerinterface.IStringEncoding
+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
 
-internal object Encoder: IStringEncoding {
-    override fun encodeString(str: String, encoding: Encoding): List<UByte> {              // TODO use Result
+
+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)
-            else -> throw FatalAstException("unsupported encoding $encoding")
+            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 {            // TODO use Result
+    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)
-            else -> throw FatalAstException("unsupported encoding $encoding")
+            Encoding.ATASCII -> AtasciiEncoding.decode(bytes)
+            else -> throw InternalCompilerException("unsupported encoding $encoding")
         }
         return decoded.fold(
             failure = { throw 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 var ESTACK_LO = 0x1a00u     //  $1a00-$1aff inclusive      // TODO
+    override var 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

@@ -1,9 +1,8 @@
-package prog8.codegen.target.c128
+package prog8.code.target.c128
 
-import prog8.codegen.target.c64.normal6502instructions
-import prog8.codegen.target.cbm.Mflpt5
-import prog8.compilerinterface.*
-import java.io.IOException
+import prog8.code.core.*
+import prog8.code.target.c64.normal6502instructions
+import prog8.code.target.cbm.Mflpt5
 import java.nio.file.Path
 
 
@@ -14,19 +13,18 @@ class C128MachineDefinition: IMachineDefinition {
     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 BASIC_LOAD_ADDRESS = 0x1c01u
-    override val RAW_LOAD_ADDRESS = 0x1300u
+    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 var ESTACK_LO = 0x1a00u     //  $1a00-$1aff inclusive
+    override var 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 == LauncherType.BASIC || compilerOptions.output == OutputType.PRG)
+        return if (compilerOptions.launcher == CbmPrgLauncherType.BASIC || compilerOptions.output == OutputType.PRG)
             listOf("syslib")
         else
             emptyList()
@@ -38,21 +36,13 @@ class C128MachineDefinition: IMachineDefinition {
             return
         }
 
-        for(emulator in listOf("x128")) {
-            println("\nStarting C-128 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
-        }
+        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

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

@@ -1,9 +1,10 @@
-package prog8.codegen.target.c128
+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
 
-import prog8.compilerinterface.CompilationOptions
-import prog8.compilerinterface.InternalCompilerException
-import prog8.compilerinterface.Zeropage
-import prog8.compilerinterface.ZeropageType
 
 class C128Zeropage(options: CompilationOptions) : Zeropage(options) {
 

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

@@ -1,7 +1,7 @@
-package prog8.codegen.target.c64
+package prog8.code.target.c64
 
-import prog8.codegen.target.cbm.Mflpt5
-import prog8.compilerinterface.*
+import prog8.code.core.*
+import prog8.code.target.cbm.Mflpt5
 import java.io.IOException
 import java.nio.file.Path
 
@@ -13,19 +13,18 @@ class C64MachineDefinition: IMachineDefinition {
     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 BASIC_LOAD_ADDRESS = 0x0801u
-    override val RAW_LOAD_ADDRESS = 0xc000u
+    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 var ESTACK_LO = 0xce00u     //  $ce00-$ceff inclusive
+    override var 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)
+        return if (compilerOptions.launcher == CbmPrgLauncherType.BASIC || compilerOptions.output == OutputType.PRG)
             listOf("syslib")
         else
             emptyList()

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

@@ -1,9 +1,10 @@
-package prog8.codegen.target.c64
+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
 
-import prog8.compilerinterface.CompilationOptions
-import prog8.compilerinterface.InternalCompilerException
-import prog8.compilerinterface.Zeropage
-import prog8.compilerinterface.ZeropageType
 
 class C64Zeropage(options: CompilationOptions) : Zeropage(options) {
 
@@ -28,10 +29,9 @@ class C64Zeropage(options: CompilationOptions) : Zeropage(options) {
         } 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,
+                        0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
+                        0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
+                        0x20, 0x21, 0x22, 0x23, 0x24, 0x25,
                         0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f, 0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46,
                         0x47, 0x48, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f, 0x51, 0x52, 0x53,
                         0x57, 0x58, 0x59, 0x5a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f, 0x60,
@@ -47,8 +47,8 @@ class C64Zeropage(options: CompilationOptions) : Zeropage(options) {
             if (options.zeropage == ZeropageType.FLOATSAFE) {
                 // remove the zeropage locations used for floating point operations from the free list
                 free.removeAll(listOf(
-                        0x22, 0x23, 0x24, 0x25,
-                        0x10, 0x11, 0x12, 0x26, 0x27, 0x28, 0x29, 0x2a,
+                        0x03, 0x04, 0x10, 0x11, 0x12,
+                        0x22, 0x23, 0x24, 0x25, 0x26, 0x27, 0x28, 0x29, 0x2a,
                         0x57, 0x58, 0x59, 0x5a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f, 0x60,
                         0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68,
                         0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f, 0x70, 0x71, 0x72,

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

@@ -1,4 +1,4 @@
-package prog8.codegen.target.cbm
+package prog8.code.target.cbm
 
 import com.github.michaelbull.result.Err
 import com.github.michaelbull.result.Ok
@@ -11,7 +11,17 @@ object IsoEncoding {
 
     fun encode(str: String): Result<List<UByte>, CharConversionException> {
         return try {
-            Ok(str.toByteArray(charset).map { it.toUByte() })
+            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)
         }

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

@@ -1,7 +1,7 @@
-package prog8.codegen.target.cbm
+package prog8.code.target.cbm
 
-import prog8.compilerinterface.IMachineFloat
-import prog8.compilerinterface.InternalCompilerException
+import prog8.code.core.IMachineFloat
+import prog8.code.core.InternalCompilerException
 import kotlin.math.absoluteValue
 import kotlin.math.pow
 

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

@@ -1,9 +1,8 @@
-package prog8.codegen.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 PetsciiEncoding {
@@ -159,7 +158,7 @@ object PetsciiEncoding {
         '\uf105',    //       0x90 -> BLACK COLOR SWITCH (CUS)
         '\uf11e',    //      0x91 -> CURSOR UP (CUS)
         '\uf11b',    //      0x92 -> REVERSE VIDEO OFF (CUS)
-        '\u000c',    //       0x93 -> FORM FEED
+        '\u000c',    //       0x93 -> FORM FEED (CLEAR SCREEN)
         '\uf121',    //      0x94 -> INSERT (CUS)
         '\uf106',    //       0x95 -> BROWN COLOR SWITCH (CUS)
         '\uf107',    //       0x96 -> LIGHT RED COLOR SWITCH (CUS)
@@ -195,7 +194,7 @@ object PetsciiEncoding {
         '\u258e',    //  ▎    0xB4 -> LEFT ONE QUARTER BLOCK
         '\u258d',    //  ▍    0xB5 -> LEFT THREE EIGTHS BLOCK
         '\uf131',    //      0xB6 -> RIGHT THREE EIGHTHS BLOCK (CUS)
-        '\uf132',    //      0xB7 -> UPPER ONE QUARTER BLOCK (CUS)
+        '\uf132',    //  🮂    0xB7 -> UPPER ONE QUARTER BLOCK (CUS)
         '\uf133',    //      0xB8 -> UPPER THREE EIGHTS BLOCK (CUS)
         '\u2583',    //  ▃    0xB9 -> LOWER THREE EIGHTHS BLOCK
         '\u2713',    //  ✓    0xBA -> CHECK MARK
@@ -246,7 +245,7 @@ object PetsciiEncoding {
         '\u2595',    //  ▕    0xE7 -> RIGHT ONE EIGHTH BLOCK
         '\uf12f',    //      0xE8 -> LOWER HALF BLOCK MEDIUM SHADE (CUS)
         '\uf13a',    //      0xE9 -> MEDIUM SHADE SLASHED RIGHT (CUS)
-        '\uf130',    //      0xEA -> RIGHT ONE QUARTER BLOCK (CUS)
+        '\uf130',    //  🮇    0xEA -> RIGHT ONE QUARTER BLOCK (CUS)
         '\u251c',    //  ├    0xEB -> BOX DRAWINGS LIGHT VERTICAL AND RIGHT
         '\u2597',    //  ▗    0xEC -> QUADRANT LOWER RIGHT
         '\u2514',    //  └    0xED -> BOX DRAWINGS LIGHT UP AND RIGHT
@@ -418,7 +417,7 @@ object PetsciiEncoding {
         '\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 PetsciiEncoding {
                 }
                 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})")
                 }
             }
         }
@@ -1120,7 +1119,7 @@ object PetsciiEncoding {
                 }
                 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})")
                 }
             }
         }

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

@@ -1,8 +1,7 @@
-package prog8.codegen.target.cx16
+package prog8.code.target.cx16
 
-import prog8.codegen.target.cbm.Mflpt5
-import prog8.compilerinterface.*
-import java.io.IOException
+import prog8.code.core.*
+import prog8.code.target.cbm.Mflpt5
 import java.nio.file.Path
 
 
@@ -13,34 +12,33 @@ class CX16MachineDefinition: IMachineDefinition {
     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 BASIC_LOAD_ADDRESS = 0x0801u
-    override val RAW_LOAD_ADDRESS = 0x8000u
+    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 var ESTACK_LO = 0x0400u        //  $0400-$04ff inclusive
+    override var 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 == LauncherType.BASIC || compilerOptions.output == OutputType.PRG)
+        return if (compilerOptions.launcher == CbmPrgLauncherType.BASIC || compilerOptions.output == OutputType.PRG)
             listOf("syslib")
         else
             emptyList()
     }
 
     override fun launchEmulator(selectedEmulator: Int, programNameWithPath: Path) {
-        val emulatorName: String
+        val emulator: String
         val extraArgs: List<String>
 
         when(selectedEmulator) {
             1 -> {
-                emulatorName = "x16emu"
+                emulator = "x16emu"
                 extraArgs = emptyList()
             }
             2 -> {
-                emulatorName = "box16"
+                emulator = "box16"
                 extraArgs = listOf("-sym", viceMonListName(programNameWithPath.toString()))
             }
             else -> {
@@ -49,19 +47,11 @@ class CX16MachineDefinition: IMachineDefinition {
             }
         }
 
-        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
-        }
+        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
@@ -70,7 +60,7 @@ class CX16MachineDefinition: IMachineDefinition {
         zeropage = CX16Zeropage(compilerOptions)
     }
 
-    // 6502 opcodes (including aliases and illegal opcodes), these cannot be used as variable or label names
+    // 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",

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

@@ -1,11 +1,7 @@
-package prog8.codegen.target.cx16
+package prog8.code.target.cx16
+
+import prog8.code.core.*
 
-import prog8.ast.GlobalNamespace
-import prog8.ast.base.DataType
-import prog8.compilerinterface.CompilationOptions
-import prog8.compilerinterface.InternalCompilerException
-import prog8.compilerinterface.Zeropage
-import prog8.compilerinterface.ZeropageType
 
 class CX16Zeropage(options: CompilationOptions) : Zeropage(options) {
 
@@ -16,8 +12,12 @@ class CX16Zeropage(options: CompilationOptions) : Zeropage(options) {
 
 
     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'")
+        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.
 
@@ -30,6 +30,10 @@ class CX16Zeropage(options: CompilationOptions) : Zeropage(options) {
                     free.addAll(0x22u..0x7fu)
                     free.addAll(0xa9u..0xffu)
                 }
+                ZeropageType.FLOATSAFE -> {
+                    free.addAll(0x22u..0x7fu)
+                    free.addAll(0xd4u..0xffu)
+                }
                 ZeropageType.BASICSAFE -> {
                     free.addAll(0x22u..0x7fu)
                 }
@@ -41,16 +45,16 @@ class CX16Zeropage(options: CompilationOptions) : Zeropage(options) {
 
             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.
-            val dummyscope = GlobalNamespace(emptyList())
+            // 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.
+            // This is important because the compiler sometimes treats ZP variables more efficiently (for example if it's a pointer)
             for(reg in 0..15) {
-                allocatedVariables[listOf("cx16", "r${reg}")]   = ZpAllocation((2+reg*2).toUInt(), DataType.UWORD, 2, dummyscope, null, null)        // cx16.r0 .. cx16.r15
-                allocatedVariables[listOf("cx16", "r${reg}s")]  = ZpAllocation((2+reg*2).toUInt(), DataType.WORD, 2, dummyscope, null, null)        // cx16.r0s .. cx16.r15s
-                allocatedVariables[listOf("cx16", "r${reg}L")]  = ZpAllocation((2+reg*2).toUInt(), DataType.UBYTE, 1, dummyscope, null, null)       // cx16.r0L .. cx16.r15L
-                allocatedVariables[listOf("cx16", "r${reg}H")]  = ZpAllocation((3+reg*2).toUInt(), DataType.UBYTE, 1, dummyscope, null, null)       // cx16.r0H .. cx16.r15H
-                allocatedVariables[listOf("cx16", "r${reg}sL")] = ZpAllocation((2+reg*2).toUInt(), DataType.BYTE, 1, dummyscope, null, null)       // cx16.r0sL .. cx16.r15sL
-                allocatedVariables[listOf("cx16", "r${reg}sH")] = ZpAllocation((3+reg*2).toUInt(), DataType.BYTE, 1, dummyscope, null, null)       // cx16.r0sH .. cx16.r15sH
+                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 var ESTACK_LO = 0u                 // not actually used
+    override var 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

@@ -24,11 +24,12 @@ compileTestKotlin {
 }
 
 dependencies {
-    implementation project(':compilerInterfaces')
+    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:1.1.12"
+    implementation "com.michael-bull.kotlin-result:kotlin-result-jvm:1.1.16"
 
 }
 

codeGenCpu6502/codeGenCpu6502.iml

@@ -9,8 +9,9 @@
     <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="module" module-name="compilerInterfaces" />
     <orderEntry type="library" name="michael.bull.kotlin.result.jvm" level="project" />
   </component>
 </module>

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

@@ -3,45 +3,48 @@ package prog8.codegen.cpu6502
 import com.github.michaelbull.result.fold
 import prog8.ast.IFunctionCall
 import prog8.ast.Node
+import prog8.ast.ParentSentinel
 import prog8.ast.Program
-import prog8.ast.base.*
+import prog8.ast.base.FatalAstException
 import prog8.ast.expressions.*
 import prog8.ast.statements.*
-import prog8.ast.toHex
+import prog8.code.SymbolTable
+import prog8.code.core.*
 import prog8.codegen.cpu6502.assignment.*
-import prog8.compilerinterface.*
-import prog8.parser.SourceCode
+import prog8.compiler.BuiltinFunctions
+import prog8.compiler.builtinFunctionReturnType
 import java.util.*
 import kotlin.io.path.Path
 import kotlin.io.path.writeLines
 
 
-internal const val generatedLabelPrefix = "prog8_label_"
 internal const val subroutineFloatEvalResultVar1 = "prog8_float_eval_result1"
 internal const val subroutineFloatEvalResultVar2 = "prog8_float_eval_result2"
 
 
 class AsmGen(internal val program: Program,
-             internal val errors: IErrorReporter,
-             internal val variables: IVariablesAndConsts,
-             internal val options: CompilationOptions): IAssemblyGenerator {
+             internal val symbolTable: SymbolTable,
+             internal val options: CompilationOptions,
+             internal val errors: IErrorReporter
+): IAssemblyGenerator {
 
     internal val optimizedByteMultiplications = setOf(3,5,6,7,9,10,11,12,13,14,15,20,25,40,50,80,100)
     internal val optimizedWordMultiplications = setOf(3,5,6,7,9,10,12,15,20,25,40,50,80,100,320,640)
     internal val loopEndLabels = ArrayDeque<String>()
     private val zeropage = options.compTarget.machine.zeropage
-    private val allocator = VariableAllocator(variables, options, errors)
+    private val allocator = VariableAllocator(symbolTable, options, errors)
     private val assemblyLines = mutableListOf<String>()
     private val breakpointLabels = mutableListOf<String>()
     private val forloopsAsmGen = ForLoopsAsmGen(program, this, zeropage)
     private val postincrdecrAsmGen = PostIncrDecrAsmGen(program, this)
     private val functioncallAsmGen = FunctionCallAsmGen(program, this)
     private val expressionsAsmGen = ExpressionsAsmGen(program, this, allocator)
-    private val programGen = ProgramAndVarsGen(program, variables, options, errors, functioncallAsmGen, this, allocator, zeropage)
+    private val programGen = ProgramAndVarsGen(program, options, errors, symbolTable, functioncallAsmGen, this, allocator, zeropage)
     private val assignmentAsmGen = AssignmentAsmGen(program, this, allocator)
     private val builtinFunctionsAsmGen = BuiltinFunctionsAsmGen(program, this, assignmentAsmGen, allocator)
 
     override fun compileToAssembly(): IAssemblyProgram? {
+
         assemblyLines.clear()
         loopEndLabels.clear()
 
@@ -68,26 +71,13 @@ class AsmGen(internal val program: Program,
     }
 
     internal fun isTargetCpu(cpu: CpuType) = options.compTarget.machine.cpu == cpu
-    internal fun haveFPWRcall() = options.compTarget.name=="cx16"
-
-    internal fun asmsubArgsEvalOrder(sub: Subroutine) =
-        options.compTarget.asmsubArgsEvalOrder(sub)
-    internal fun asmsubArgsHaveRegisterClobberRisk(args: List<Expression>, paramRegisters: List<RegisterOrStatusflag>) =
-        options.compTarget.asmsubArgsHaveRegisterClobberRisk(args, paramRegisters)
-
-    private var generatedLabelSequenceNumber: Int = 0
-
-    internal fun makeLabel(postfix: String): String {
-        generatedLabelSequenceNumber++
-        return "${generatedLabelPrefix}${generatedLabelSequenceNumber}_$postfix"
-    }
 
     internal fun outputSourceLine(node: Node) {
         out(" ;\tsrc line: ${node.position.file}:${node.position.line}")
     }
 
     internal fun out(str: String, splitlines: Boolean = true) {
-        val fragment = (if(" | " in str) str.replace("|", "\n") else str).trim('\n')
+        val fragment = (if(splitlines && " | " in str) str.replace("|", "\n") else str).trim('\n')
         if (splitlines) {
             for (line in fragment.splitToSequence('\n')) {
                 val trimmed = if (line.startsWith(' ')) "\t" + line.trim() else line
@@ -233,11 +223,11 @@ class AsmGen(internal val program: Program,
                 }
                 CpuRegister.X -> {
                     out("  stx  prog8_regsaveX")
-                    allocator.subroutineExtra(scope).usedRegsaveX = true
+                    subroutineExtra(scope).usedRegsaveX = true
                 }
                 CpuRegister.Y -> {
                     out("  sty  prog8_regsaveY")
-                    allocator.subroutineExtra(scope).usedRegsaveY = true
+                    subroutineExtra(scope).usedRegsaveY = true
                 }
             }
         }
@@ -320,15 +310,8 @@ class AsmGen(internal val program: Program,
             is Return -> translate(stmt)
             is Subroutine -> programGen.translateSubroutine(stmt)
             is InlineAssembly -> translate(stmt)
-            is FunctionCallStatement -> {
-                val functionName = stmt.target.nameInSource.last()
-                val builtinFunc = BuiltinFunctions[functionName]
-                if (builtinFunc != null) {
-                    builtinFunctionsAsmGen.translateFunctioncallStatement(stmt, builtinFunc)
-                } else {
-                    functioncallAsmGen.translateFunctionCallStatement(stmt)
-                }
-            }
+            is BuiltinFunctionCallStatement -> builtinFunctionsAsmGen.translateFunctioncallStatement(stmt)
+            is FunctionCallStatement -> functioncallAsmGen.translateFunctionCallStatement(stmt)         // TODO try to remove this last usage of FunctionCallStatement node in the codegen.
             is Assignment -> assignmentAsmGen.translate(stmt)
             is Jump -> {
                 val (asmLabel, indirect) = getJumpTarget(stmt)
@@ -343,7 +326,6 @@ class AsmGen(internal val program: Program,
             is RepeatLoop -> translate(stmt)
             is When -> translate(stmt)
             is AnonymousScope -> translate(stmt)
-            is Pipe -> translatePipeExpression(stmt.expressions, stmt, true, false)
             is VarDecl -> { /* do nothing; variables are handled elsewhere */ }
             is BuiltinFunctionPlaceholder -> throw AssemblyError("builtin function should not have placeholder anymore")
             is UntilLoop -> throw AssemblyError("do..until should have been converted to jumps")
@@ -450,14 +432,8 @@ class AsmGen(internal val program: Program,
     internal fun translateExpression(expression: Expression) =
             expressionsAsmGen.translateExpression(expression)
 
-    internal fun translateBuiltinFunctionCallExpression(functionCallExpr: FunctionCallExpression, signature: FSignature, resultToStack: Boolean, resultRegister: RegisterOrPair?) =
-            builtinFunctionsAsmGen.translateFunctioncallExpression(functionCallExpr, signature, resultToStack, resultRegister)
-
-    internal fun translateBuiltinFunctionCallExpression(name: String, args: List<AsmAssignSource>, scope: Subroutine): DataType =
-            builtinFunctionsAsmGen.translateFunctioncall(name, args, false, scope)
-
-    internal fun translateBuiltinFunctionCallStatement(name: String, args: List<AsmAssignSource>, scope: Subroutine) =
-            builtinFunctionsAsmGen.translateFunctioncall(name, args, true, scope)
+    internal fun translateBuiltinFunctionCallExpression(bfc: BuiltinFunctionCall, resultToStack: Boolean, resultRegister: RegisterOrPair?) =
+            builtinFunctionsAsmGen.translateFunctioncallExpression(bfc, resultToStack, resultRegister)
 
     internal fun translateFunctionCall(functionCallExpr: FunctionCallExpression, isExpression: Boolean) =
             functioncallAsmGen.translateFunctionCall(functionCallExpr, isExpression)
@@ -559,7 +535,7 @@ class AsmGen(internal val program: Program,
             if(jump is Jump) {
                 translateCompareAndJumpIfTrue(booleanCondition, jump)
             } else {
-                val endLabel = makeLabel("if_end")
+                val endLabel = program.makeLabel("if_end")
                 translateCompareAndJumpIfFalse(booleanCondition, endLabel)
                 translate(stmt.truepart)
                 out(endLabel)
@@ -567,8 +543,8 @@ class AsmGen(internal val program: Program,
         }
         else {
             // both true and else parts
-            val elseLabel = makeLabel("if_else")
-            val endLabel = makeLabel("if_end")
+            val elseLabel = program.makeLabel("if_else")
+            val endLabel = program.makeLabel("if_end")
             translateCompareAndJumpIfFalse(booleanCondition, elseLabel)
             translate(stmt.truepart)
             jmp(endLabel)
@@ -584,18 +560,11 @@ class AsmGen(internal val program: Program,
     }
 
     private fun translate(stmt: RepeatLoop) {
-        val endLabel = makeLabel("repeatend")
+        val endLabel = program.makeLabel("repeatend")
         loopEndLabels.push(endLabel)
 
         when (stmt.iterations) {
-            null -> {
-                // endless loop
-                val repeatLabel = makeLabel("repeat")
-                out(repeatLabel)
-                translate(stmt.body)
-                jmp(repeatLabel)
-                out(endLabel)
-            }
+            null -> throw AssemblyError("repeat-forever loop should have been replaced by label+jump")
             is NumericLiteral -> {
                 val iterations = (stmt.iterations as NumericLiteral).number.toInt()
                 when {
@@ -644,7 +613,7 @@ class AsmGen(internal val program: Program,
 
     private fun repeatWordCount(count: Int, stmt: RepeatLoop) {
         require(count in 257..65535)
-        val repeatLabel = makeLabel("repeat")
+        val repeatLabel = program.makeLabel("repeat")
         if(isTargetCpu(CpuType.CPU65c02)) {
             val counterVar = createRepeatCounterVar(DataType.UWORD, true, stmt)
             out("""
@@ -685,7 +654,7 @@ $repeatLabel""")
     private fun repeatWordCountInAY(endLabel: String, stmt: RepeatLoop) {
         // note: A/Y must have been loaded with the number of iterations!
         // no need to explicitly test for 0 iterations as this is done in the countdown logic below
-        val repeatLabel = makeLabel("repeat")
+        val repeatLabel = program.makeLabel("repeat")
         val counterVar = createRepeatCounterVar(DataType.UWORD, false, stmt)
         out("""
                 sta  $counterVar
@@ -706,7 +675,7 @@ $repeatLabel    lda  $counterVar
 
     private fun repeatByteCount(count: Int, stmt: RepeatLoop) {
         require(count in 2..256)
-        val repeatLabel = makeLabel("repeat")
+        val repeatLabel = program.makeLabel("repeat")
         if(isTargetCpu(CpuType.CPU65c02)) {
             val counterVar = createRepeatCounterVar(DataType.UBYTE, true, stmt)
             out("  lda  #${count and 255} |  sta  $counterVar")
@@ -724,7 +693,7 @@ $repeatLabel    lda  $counterVar
 
     private fun repeatCountInY(stmt: RepeatLoop, endLabel: String) {
         // note: Y must just have been loaded with the (variable) number of loops to be performed!
-        val repeatLabel = makeLabel("repeat")
+        val repeatLabel = program.makeLabel("repeat")
         if(isTargetCpu(CpuType.CPU65c02)) {
             val counterVar = createRepeatCounterVar(DataType.UBYTE, true, stmt)
             out("  beq  $endLabel |  sty  $counterVar")
@@ -743,7 +712,7 @@ $repeatLabel    lda  $counterVar
 
     private fun createRepeatCounterVar(dt: DataType, preferZeropage: Boolean, stmt: RepeatLoop): String {
         val scope = stmt.definingSubroutine!!
-        val asmInfo = allocator.subroutineExtra(scope)
+        val asmInfo = subroutineExtra(scope)
         var parent = stmt.parent
         while(parent !is ParentSentinel) {
             if(parent is RepeatLoop)
@@ -761,10 +730,10 @@ $repeatLabel    lda  $counterVar
             }
         }
 
-        val counterVar = makeLabel("counter")
+        val counterVar = program.makeLabel("counter")
         when(dt) {
             DataType.UBYTE, DataType.UWORD -> {
-                val result = zeropage.allocate(listOf(counterVar), dt, scope,null, null, stmt.position, errors)
+                val result = zeropage.allocate(listOf(counterVar), dt, null, stmt.position, errors)
                 result.fold(
                     success = { (address, _) -> asmInfo.extraVars.add(Triple(dt, counterVar, address)) },
                     failure = { asmInfo.extraVars.add(Triple(dt, counterVar, null)) }  // allocate normally
@@ -776,7 +745,7 @@ $repeatLabel    lda  $counterVar
     }
 
     private fun translate(stmt: When) {
-        val endLabel = makeLabel("choice_end")
+        val endLabel = program.makeLabel("choice_end")
         val choiceBlocks = mutableListOf<Pair<String, AnonymousScope>>()
         val conditionDt = stmt.condition.inferType(program)
         if(!conditionDt.isKnown)
@@ -787,7 +756,7 @@ $repeatLabel    lda  $counterVar
             assignExpressionToRegister(stmt.condition, RegisterOrPair.AY)
 
         for(choice in stmt.choices) {
-            val choiceLabel = makeLabel("choice")
+            val choiceLabel = program.makeLabel("choice")
             if(choice.values==null) {
                 // the else choice
                 translate(choice.statements)
@@ -851,14 +820,14 @@ $repeatLabel    lda  $counterVar
         } else {
             if(stmt.elsepart.isEmpty()) {
                 val instruction = branchInstruction(stmt.condition, true)
-                val elseLabel = makeLabel("branch_else")
+                val elseLabel = program.makeLabel("branch_else")
                 out("  $instruction  $elseLabel")
                 translate(stmt.truepart)
                 out(elseLabel)
             } else {
                 val instruction = branchInstruction(stmt.condition, true)
-                val elseLabel = makeLabel("branch_else")
-                val endLabel = makeLabel("branch_end")
+                val elseLabel = program.makeLabel("branch_else")
+                val endLabel = program.makeLabel("branch_end")
                 out("  $instruction  $elseLabel")
                 translate(stmt.truepart)
                 jmp(endLabel)
@@ -874,7 +843,7 @@ $repeatLabel    lda  $counterVar
             "%asminclude" -> {
                 val includedName = stmt.args[0].str!!
                 if(stmt.definingModule.source is SourceCode.Generated)
-                    TODO("%asminclude inside non-library, non-filesystem module")
+                    throw AssemblyError("%asminclude inside non-library/non-filesystem module not yet supported")
                 loadAsmIncludeFile(includedName, stmt.definingModule.source).fold(
                     success = { assemblyLines.add(it.trimEnd().trimStart('\n')) },
                     failure = { errors.err(it.toString(), stmt.position) }
@@ -885,7 +854,7 @@ $repeatLabel    lda  $counterVar
                 val offset = if(stmt.args.size>1) ", ${stmt.args[1].int}" else ""
                 val length = if(stmt.args.size>2) ", ${stmt.args[2].int}" else ""
                 if(stmt.definingModule.source is SourceCode.Generated)
-                    TODO("%asmbinary inside non-library, non-filesystem module")
+                    throw AssemblyError("%asmbinary inside non-library/non-filesystem module not yet supported")
                 val sourcePath = Path(stmt.definingModule.source.origin)
                 val includedPath = sourcePath.resolveSibling(includedName)
                 val pathForAssembler = options.outputDir // #54: 64tass needs the path *relative to the .asm file*
@@ -904,7 +873,7 @@ $repeatLabel    lda  $counterVar
     }
 
     private fun translate(gosub: GoSub) {
-        val tgt = gosub.identifier!!.targetSubroutine(program)
+        val tgt = gosub.identifier.targetSubroutine(program)
         if(tgt!=null && tgt.isAsmSubroutine) {
             // no need to rescue X , this has been taken care of already
             out("  jsr  ${getJumpTarget(gosub)}")
@@ -934,17 +903,7 @@ $repeatLabel    lda  $counterVar
         }
     }
 
-    private fun getJumpTarget(gosub: GoSub): String {
-        val ident = gosub.identifier
-        val label = gosub.generatedLabel
-        val addr = gosub.address
-        return when {
-            ident!=null -> asmSymbolName(ident)
-            label!=null -> label
-            addr!=null -> addr.toHex()
-            else -> "????"
-        }
-    }
+    private fun getJumpTarget(gosub: GoSub): String = asmSymbolName(gosub.identifier)
 
     private fun translate(ret: Return, withRts: Boolean=true) {
         ret.value?.let { returnvalue ->
@@ -978,11 +937,19 @@ $repeatLabel    lda  $counterVar
     internal fun returnRegisterOfFunction(it: IdentifierReference): RegisterOrPair {
         return when (val targetRoutine = it.targetStatement(program)!!) {
             is BuiltinFunctionPlaceholder -> {
-                when (BuiltinFunctions.getValue(targetRoutine.name).known_returntype) {
+                val func = BuiltinFunctions.getValue(targetRoutine.name)
+                when (func.returnType) {
                     in ByteDatatypes -> RegisterOrPair.A
                     in WordDatatypes -> RegisterOrPair.AY
                     DataType.FLOAT -> RegisterOrPair.FAC1
-                    else -> throw AssemblyError("weird returntype")
+                    else -> {
+                        when(builtinFunctionReturnType(func.name).getOrElse { DataType.UNDEFINED }) {
+                            in ByteDatatypes -> RegisterOrPair.A
+                            in WordDatatypes -> RegisterOrPair.AY
+                            DataType.FLOAT -> RegisterOrPair.FAC1
+                            else -> throw AssemblyError("weird returntype")
+                        }
+                    }
                 }
             }
             is Subroutine -> targetRoutine.asmReturnvaluesRegisters.single().registerOrPair!!
@@ -1198,16 +1165,16 @@ $repeatLabel    lda  $counterVar
             return testVariableZeroAndJump(left, dt, operator, jumpIfFalseLabel)
 
         when(dt) {
-            DataType.UBYTE, DataType.UWORD -> {
+            DataType.BOOL, DataType.UBYTE, DataType.UWORD -> {
                 if(operator=="<") {
                     out("  jmp  $jumpIfFalseLabel")
                     return
                 } else if(operator==">=") {
                     return
                 }
-                if(dt==DataType.UBYTE) {
+                if(dt==DataType.UBYTE || dt==DataType.BOOL) {
                     assignExpressionToRegister(left, RegisterOrPair.A, false)
-                    if (left is FunctionCallExpression && !left.isSimple)
+                    if (left is IFunctionCall && !left.isSimple)
                         out("  cmp  #0")
                 } else {
                     assignExpressionToRegister(left, RegisterOrPair.AY, false)
@@ -1223,7 +1190,7 @@ $repeatLabel    lda  $counterVar
             }
             DataType.BYTE -> {
                 assignExpressionToRegister(left, RegisterOrPair.A, true)
-                if (left is FunctionCallExpression && !left.isSimple)
+                if (left is IFunctionCall && !left.isSimple)
                     out("  cmp  #0")
                 when (operator) {
                     "==" -> out("  bne  $jumpIfFalseLabel")
@@ -1285,7 +1252,7 @@ $repeatLabel    lda  $counterVar
         // optimized code if the expression is just an identifier (variable)
         val varname = asmVariableName(variable)
         when(dt) {
-            DataType.UBYTE -> when(operator) {
+            DataType.UBYTE, DataType.BOOL -> when(operator) {
                 "==" -> out("  lda  $varname |  bne  $jumpIfFalseLabel")
                 "!=" -> out("  lda  $varname |  beq  $jumpIfFalseLabel")
                 ">"  -> out("  lda  $varname |  beq  $jumpIfFalseLabel")
@@ -1451,7 +1418,7 @@ $repeatLabel    lda  $counterVar
                 beq  $jumpIfFalseLabel""")
         } else {
             val subroutine = left.definingSubroutine!!
-            allocator.subroutineExtra(subroutine).usedFloatEvalResultVar1 = true
+            subroutineExtra(subroutine).usedFloatEvalResultVar1 = true
             assignExpressionToVariable(right, subroutineFloatEvalResultVar1, DataType.FLOAT, subroutine)
             assignExpressionToRegister(left, RegisterOrPair.FAC1)
             out("""
@@ -1496,7 +1463,7 @@ $repeatLabel    lda  $counterVar
                 beq  $jumpIfFalseLabel""")
         } else {
             val subroutine = left.definingSubroutine!!
-            allocator.subroutineExtra(subroutine).usedFloatEvalResultVar1 = true
+            subroutineExtra(subroutine).usedFloatEvalResultVar1 = true
             assignExpressionToVariable(right, subroutineFloatEvalResultVar1, DataType.FLOAT, subroutine)
             assignExpressionToRegister(left, RegisterOrPair.FAC1)
             out("""
@@ -1541,7 +1508,7 @@ $repeatLabel    lda  $counterVar
                 beq  $jumpIfFalseLabel""")
         } else {
             val subroutine = left.definingSubroutine!!
-            allocator.subroutineExtra(subroutine).usedFloatEvalResultVar1 = true
+            subroutineExtra(subroutine).usedFloatEvalResultVar1 = true
             assignExpressionToVariable(right, subroutineFloatEvalResultVar1, DataType.FLOAT, subroutine)
             assignExpressionToRegister(left, RegisterOrPair.FAC1)
             out("""
@@ -1586,7 +1553,7 @@ $repeatLabel    lda  $counterVar
                 beq  $jumpIfFalseLabel""")
         } else {
             val subroutine = left.definingSubroutine!!
-            allocator.subroutineExtra(subroutine).usedFloatEvalResultVar1 = true
+            subroutineExtra(subroutine).usedFloatEvalResultVar1 = true
             assignExpressionToVariable(right, subroutineFloatEvalResultVar1, DataType.FLOAT, subroutine)
             assignExpressionToRegister(left, RegisterOrPair.FAC1)
             out("""
@@ -2526,7 +2493,7 @@ $repeatLabel    lda  $counterVar
                 beq  $jumpIfFalseLabel""")
         } else {
             val subroutine = left.definingSubroutine!!
-            allocator.subroutineExtra(subroutine).usedFloatEvalResultVar1 = true
+            subroutineExtra(subroutine).usedFloatEvalResultVar1 = true
             assignExpressionToVariable(right, subroutineFloatEvalResultVar1, DataType.FLOAT, subroutine)
             assignExpressionToRegister(left, RegisterOrPair.FAC1)
             out("""
@@ -2611,7 +2578,7 @@ $repeatLabel    lda  $counterVar
                 bne  $jumpIfFalseLabel""")
         } else {
             val subroutine = left.definingSubroutine!!
-            allocator.subroutineExtra(subroutine).usedFloatEvalResultVar1 = true
+            subroutineExtra(subroutine).usedFloatEvalResultVar1 = true
             assignExpressionToVariable(right, subroutineFloatEvalResultVar1, DataType.FLOAT, subroutine)
             assignExpressionToRegister(left, RegisterOrPair.FAC1)
             out("""
@@ -2830,55 +2797,141 @@ $repeatLabel    lda  $counterVar
         }
     }
 
-    internal fun translatePipeExpression(expressions: Iterable<Expression>, scope: Node, isStatement: Boolean, pushResultOnEstack: Boolean) {
-
-        // TODO more efficient code generation to avoid needless assignments to the temp var
-
-        // the first term: an expression (could be anything) producing a value.
-        val subroutine = scope.definingSubroutine!!
-        val firstTerm = expressions.first()
-        var valueDt = firstTerm.inferType(program).getOrElse { throw FatalAstException("invalid dt") }
-        var valueSource: AsmAssignSource =
-            if(firstTerm is IFunctionCall) {
-                val resultReg = returnRegisterOfFunction(firstTerm.target)
-                assignExpressionToRegister(firstTerm, resultReg, valueDt in listOf(DataType.BYTE, DataType.WORD, DataType.FLOAT))
-                AsmAssignSource(SourceStorageKind.REGISTER, program, this, valueDt, register = resultReg)
-            } else {
-                AsmAssignSource.fromAstSource(firstTerm, program, this)
+    internal fun popCpuStack(dt: DataType, target: VarDecl, scope: Subroutine?) {
+        // note: because A is pushed first so popped last, saving A is often not required here.
+        val parameter = target.subroutineParameter
+        if(parameter!=null) {
+            val sub = parameter.definingSubroutine!!
+            require(sub.isAsmSubroutine) { "push/pop arg passing only supported on asmsubs" }
+            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)
+                    out("  sta  P8ZP_SCRATCH_REG")
+                out("""
+                    clc
+                    pla
+                    beq  +
+                    sec
++""")
+                if(shouldKeepA)
+                    out("  lda  P8ZP_SCRATCH_REG")
             }
-
-        // the 2nd to N-1 terms: unary function calls taking a single param and producing a value.
-        //   directly assign their argument from the previous call's returnvalue.
-        expressions.drop(1).dropLast(1).forEach {
-            valueDt = functioncallAsmGen.translateUnaryFunctionCallWithArgSource(it as IdentifierReference, valueSource, false, subroutine)
-            val resultReg = returnRegisterOfFunction(it)
-            valueSource = AsmAssignSource(SourceStorageKind.REGISTER, program, this, valueDt, register = resultReg)
-        }
-
-        // the last term: unary function call taking a single param and optionally producing a result value.
-        if(isStatement) {
-            // the last term in the pipe, don't care about return var:
-            functioncallAsmGen.translateUnaryFunctionCallWithArgSource(
-                expressions.last() as IdentifierReference, valueSource, true, subroutine)
-        } else {
-            // the last term in the pipe, regular function call with returnvalue:
-            valueDt = functioncallAsmGen.translateUnaryFunctionCallWithArgSource(
-                expressions.last() as IdentifierReference, valueSource, false, subroutine)
-            if(pushResultOnEstack) {
-                when (valueDt) {
-                    in ByteDatatypes -> {
-                        out("  sta  P8ESTACK_LO,x |  dex")
+            else {
+                if (dt in ByteDatatypes) {
+                    if (isTargetCpu(CpuType.CPU65c02)) {
+                        when (reg.registerOrPair) {
+                            RegisterOrPair.A -> out("  pla")
+                            RegisterOrPair.X -> out("  plx")
+                            RegisterOrPair.Y -> out("  ply")
+                            in Cx16VirtualRegisters -> out("  pla |  sta  cx16.${reg.registerOrPair!!.name.lowercase()}")
+                            else -> throw AssemblyError("invalid target register ${reg.registerOrPair}")
+                        }
+                    } else {
+                        when (reg.registerOrPair) {
+                            RegisterOrPair.A -> out("  pla")
+                            RegisterOrPair.X -> {
+                                if(shouldKeepA)
+                                    out("  sta  P8ZP_SCRATCH_REG |  pla |  tax |  lda  P8ZP_SCRATCH_REG")
+                                else
+                                    out("  pla |  tax")
+                            }
+                            RegisterOrPair.Y -> {
+                                if(shouldKeepA)
+                                    out("  sta  P8ZP_SCRATCH_REG |  pla |  tay |  lda  P8ZP_SCRATCH_REG")
+                                else
+                                    out("  pla |  tay")
+                            }
+                            in Cx16VirtualRegisters -> out("  pla |  sta  cx16.${reg.registerOrPair!!.name.lowercase()}")
+                            else -> throw AssemblyError("invalid target register ${reg.registerOrPair}")
+                        }
                     }
-                    in WordDatatypes -> {
-                        out("  sta  P8ESTACK_LO,x |  tya |  sta  P8ESTACK_HI,x |  dex")
+                } else {
+                    // word pop
+                    if (isTargetCpu(CpuType.CPU65c02))
+                        when (reg.registerOrPair) {
+                            RegisterOrPair.AX -> out("  plx |  pla")
+                            RegisterOrPair.AY -> out("  ply |  pla")
+                            RegisterOrPair.XY -> out("  ply |  plx")
+                            in Cx16VirtualRegisters -> {
+                                val regname = reg.registerOrPair!!.name.lowercase()
+                                out("  pla |  sta  cx16.$regname+1 |  pla |  sta  cx16.$regname")
+                            }
+                            else -> throw AssemblyError("invalid target register ${reg.registerOrPair}")
+                        }
+                    else {
+                        when (reg.registerOrPair) {
+                            RegisterOrPair.AX -> out("  pla |  tax |  pla")
+                            RegisterOrPair.AY -> out("  pla |  tay |  pla")
+                            RegisterOrPair.XY -> out("  pla |  tay |  pla |  tax")
+                            in Cx16VirtualRegisters -> {
+                                val regname = reg.registerOrPair!!.name.lowercase()
+                                out("  pla |  sta  cx16.$regname+1 |  pla |  sta  cx16.$regname")
+                            }
+                            else -> throw AssemblyError("invalid target register ${reg.registerOrPair}")
+                        }
                     }
-                    DataType.FLOAT -> {
-                        out("  jsr  floats.push_fac1")
-                    }
-                    else -> throw AssemblyError("invalid dt")
                 }
             }
+        } else {
+            val tgt = AsmAssignTarget(TargetStorageKind.VARIABLE, program, this, target.datatype, scope, variableAsmName = asmVariableName(target.scopedName))
+            if (dt in ByteDatatypes) {
+                out("  pla")
+                assignRegister(RegisterOrPair.A, tgt)
+            } else {
+                if (isTargetCpu(CpuType.CPU65c02))
+                    out("  ply |  pla")
+                else
+                    out("  pla |  tay |  pla")
+                assignRegister(RegisterOrPair.AY, tgt)
+            }
         }
     }
 
+    internal fun pushCpuStack(dt: DataType, value: Expression) {
+        val signed = value.inferType(program).oneOf(DataType.BYTE, DataType.WORD)
+        if(dt in ByteDatatypes) {
+            assignExpressionToRegister(value, RegisterOrPair.A, signed)
+            out("  pha")
+        } else {
+            assignExpressionToRegister(value, RegisterOrPair.AY, signed)
+            if (isTargetCpu(CpuType.CPU65c02))
+                out("  pha |  phy")
+            else
+                out("  pha |  tya |  pha")
+        }
+    }
+
+    internal fun needAsaveForExpr(arg: Expression): Boolean =
+        arg !is NumericLiteral && arg !is IdentifierReference && (arg !is DirectMemoryRead || !arg.isSimple)
+
+    private val subroutineExtrasCache = mutableMapOf<Subroutine, SubroutineExtraAsmInfo>()
+
+    internal fun subroutineExtra(sub: Subroutine): SubroutineExtraAsmInfo {
+        var extra = subroutineExtrasCache[sub]
+        return if(extra==null) {
+            extra = SubroutineExtraAsmInfo()
+            subroutineExtrasCache[sub] = extra
+            extra
+        }
+        else
+            extra
+    }
 }
+
+
+/**
+ * Contains various attributes that influence the assembly code generator.
+ * Conceptually it should be part of any INameScope.
+ * But because the resulting code only creates "real" scopes on a subroutine level,
+ * it's more consistent to only define these attributes on a Subroutine node.
+ */
+internal class SubroutineExtraAsmInfo {
+    var usedRegsaveA = false
+    var usedRegsaveX = false
+    var usedRegsaveY = false
+    var usedFloatEvalResultVar1 = false
+    var usedFloatEvalResultVar2 = false
+
+    val extraVars = mutableListOf<Triple<DataType, String, UInt?>>()
+}

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

@@ -1,10 +1,10 @@
 package prog8.codegen.cpu6502
 
 import prog8.ast.Program
-import prog8.ast.base.VarDeclType
 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

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

@@ -1,15 +1,15 @@
-package prog8.codegen.target.cbm
+package prog8.codegen.cpu6502
 
-import prog8.ast.base.Cx16VirtualRegisters
-import prog8.ast.base.RegisterOrPair
 import prog8.ast.expressions.ArrayIndexedExpression
+import prog8.ast.expressions.BuiltinFunctionCall
 import prog8.ast.expressions.Expression
-import prog8.ast.expressions.FunctionCallExpression
-import prog8.ast.statements.RegisterOrStatusflag
 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,
@@ -37,7 +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) {
@@ -46,10 +46,10 @@ internal fun asmsub6502ArgsHaveRegisterClobberRisk(args: List<Expression>,
                     it.registerOrPair in listOf(RegisterOrPair.Y, RegisterOrPair.AY, RegisterOrPair.XY)
                 }
             }
-            is FunctionCallExpression -> {
-                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

@@ -3,8 +3,8 @@ package prog8.codegen.cpu6502
 import com.github.michaelbull.result.Ok
 import com.github.michaelbull.result.Result
 import com.github.michaelbull.result.mapError
-import prog8.compilerinterface.*
-import prog8.parser.SourceCode
+import prog8.ast.generatedLabelPrefix
+import prog8.code.core.*
 import java.io.File
 import java.nio.file.Path
 import kotlin.io.path.Path
@@ -17,41 +17,86 @@ internal class AssemblyProgram(
         private val compTarget: ICompilationTarget) : IAssemblyProgram {
 
     private val assemblyFile = outputDir.resolve("$name.asm")
-    private val prgFile = outputDir.resolve("$name.prg")
+    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 {
-        // 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")
+        val assemblerCommand: List<String>
 
-        if(options.asmListfile)
-            command.add("--list=$listFile")
+        when (compTarget.name) {
+            in setOf("c64", "c128", "cx16") -> {
+                // CBM machines .prg generation.
+
+                // add "-Wlong-branch"  to see warnings about conversion of branch instructions to jumps (default = do this silently)
+                val command = mutableListOf("64tass", "--ascii", "--case-sensitive", "--long-branch",
+                    "-Wall", "-Wno-strict-bool", "-Wno-shadow", // "-Werror",
+                    "--dump-labels", "--vice-labels", "--labels=$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
 
-        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 ${compTarget.name}.")
-                binFile
+            "atari" -> {
+                // Atari800XL .xex generation.
+
+                // TODO are these options okay?
+                val command = mutableListOf("64tass", "--ascii", "--case-sensitive", "--long-branch",
+                    "-Wall", "-Wno-strict-bool", "-Wno-shadow", // "-Werror",
+                    "--no-monitor"
+                )
+
+                if(options.asmQuiet)
+                    command.add("--quiet")
+
+                if(options.asmListfile)
+                    command.add("--list=$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")
         }
-        command.addAll(listOf("--output", outFile.toString(), assemblyFile.toString()))
 
-        val proc = ProcessBuilder(command).inheritIO().start()
+        val proc = ProcessBuilder(assemblerCommand).inheritIO().start()
         val result = proc.waitFor()
-        if (result == 0) {
+        if (result == 0 && compTarget.name!="atari") {
             removeGeneratedLabelsFromMonlist()
             generateBreakpointList()
         }

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

@@ -3,18 +3,14 @@ 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.DirectMemoryWrite
-import prog8.ast.statements.FunctionCallStatement
+import prog8.ast.statements.BuiltinFunctionCallStatement
 import prog8.ast.statements.Subroutine
-import prog8.ast.toHex
+import prog8.code.core.*
 import prog8.codegen.cpu6502.assignment.*
-import prog8.compilerinterface.AssemblyError
-import prog8.compilerinterface.BuiltinFunctions
-import prog8.compilerinterface.CpuType
-import prog8.compilerinterface.FSignature
+import prog8.compiler.BuiltinFunctions
+import prog8.compiler.FSignature
 
 
 internal class BuiltinFunctionsAsmGen(private val program: Program,
@@ -22,45 +18,16 @@ internal class BuiltinFunctionsAsmGen(private val program: Program,
                                       private val assignAsmGen: AssignmentAsmGen,
                                       private val allocations: VariableAllocator) {
 
-    internal fun translateFunctioncallExpression(fcall: FunctionCallExpression, func: FSignature, resultToStack: Boolean, resultRegister: RegisterOrPair?) {
+    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 translateFunctioncall(name: String, args: List<AsmAssignSource>, isStatement: Boolean, scope: Subroutine): DataType {
-        val func = BuiltinFunctions.getValue(name)
-        val argExpressions = args.map { src ->
-            when(src.kind) {
-                SourceStorageKind.LITERALNUMBER -> src.number!!
-                SourceStorageKind.EXPRESSION -> src.expression!!
-                SourceStorageKind.ARRAY -> src.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
-                    val tempvar = asmgen.getTempVarName(src.datatype)
-                    val assignTempvar = AsmAssignment(
-                        src,
-                        AsmAssignTarget(TargetStorageKind.VARIABLE, program, asmgen, src.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
-                }
-            }
-        }.toMutableList()
-        val fcall = FunctionCallExpression(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 func.known_returntype!!
-    }
-
     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
@@ -75,19 +42,8 @@ internal class BuiltinFunctionsAsmGen(private val program: Program,
             "lsb" -> funcLsb(fcall, resultToStack, resultRegister)
             "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)
@@ -102,8 +58,20 @@ internal class BuiltinFunctionsAsmGen(private val program: Program,
             "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()
@@ -166,136 +134,24 @@ internal class BuiltinFunctionsAsmGen(private val program: Program,
             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.name != "cx16")
             throw AssemblyError("callfar only works on cx16 target at this time")
 
         val bank = fcall.args[0].constValue(program)?.number?.toInt()
-        val address = fcall.args[1].constValue(program)?.number?.toInt()
-        if(bank==null || address==null)
-            throw AssemblyError("callfar (jsrfar) requires constant arguments")
-
-        if(address !in 0xa000..0xbfff)
-            throw AssemblyError("callfar done on address outside of cx16 banked ram")
-        if(bank==0)
-            throw AssemblyError("callfar done on bank 0 which is reserved for the kernal")
-
+        val address = fcall.args[1].constValue(program)?.number?.toInt() ?: 0
         val argAddrArg = fcall.args[2]
+        if(bank==null)
+            throw AssemblyError("callfar (jsrfar) bank has to be a constant")
+        if(fcall.args[1].constValue(program) == null) {
+            assignAsmGen.assignExpressionToRegister(fcall.args[1], RegisterOrPair.AY, false)
+            asmgen.out("  sta  (+)+0 |  sty  (+)+1  ; store jsrfar address word")
+        }
+
         if(argAddrArg.constValue(program)?.number == 0.0) {
             asmgen.out("""
                 jsr  cx16.jsrfar
-                .word  ${address.toHex()}
++               .word  ${address.toHex()}
                 .byte  ${bank.toHex()}""")
         } else {
             when(argAddrArg) {
@@ -305,7 +161,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program,
                     asmgen.out("""
                         lda  ${asmgen.asmVariableName(argAddrArg.identifier)}
                         jsr  cx16.jsrfar
-                        .word  ${address.toHex()}
++                       .word  ${address.toHex()}
                         .byte  ${bank.toHex()}
                         sta  ${asmgen.asmVariableName(argAddrArg.identifier)}""")
                 }
@@ -313,7 +169,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program,
                     asmgen.out("""
                         lda  ${argAddrArg.number.toHex()}
                         jsr  cx16.jsrfar
-                        .word  ${address.toHex()}
++                       .word  ${address.toHex()}
                         .byte  ${bank.toHex()}
                         sta  ${argAddrArg.number.toHex()}""")
                 }
@@ -449,7 +305,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program,
     }
 
     private fun funcMemory(fcall: IFunctionCall, discardResult: Boolean, resultToStack: Boolean, resultRegister: RegisterOrPair?) {
-        if(discardResult || fcall !is FunctionCallExpression)
+        if(discardResult || fcall !is BuiltinFunctionCall)
             throw AssemblyError("should not discard result of memory allocation at $fcall")
         val name = (fcall.args[0] as StringLiteral).value
         require(name.all { it.isLetterOrDigit() || it=='_' }) {"memory name should be a valid symbol name"}
@@ -483,23 +339,6 @@ internal class BuiltinFunctionsAsmGen(private val program: Program,
         }
     }
 
-    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) {
@@ -631,14 +470,16 @@ internal class BuiltinFunctionsAsmGen(private val program: Program,
                         } else {
                             val ptrAndIndex = asmgen.pointerViaIndexRegisterPossible(what.addressExpression)
                             if(ptrAndIndex!=null) {
+                                asmgen.saveRegisterLocal(CpuRegister.X, (fcall as Node).definingSubroutine!!)
                                 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("""
                                     sta  (+) + 1
                                     sty  (+) + 2
 +                                   ror  ${'$'}ffff,x           ; modified""")
+                                asmgen.restoreRegisterLocal(CpuRegister.X)
                             } else {
                                 asmgen.assignExpressionToRegister(what.addressExpression, RegisterOrPair.AY)
                                 asmgen.out("""
@@ -732,14 +573,16 @@ internal class BuiltinFunctionsAsmGen(private val program: Program,
                         } else {
                             val ptrAndIndex = asmgen.pointerViaIndexRegisterPossible(what.addressExpression)
                             if(ptrAndIndex!=null) {
+                                asmgen.saveRegisterLocal(CpuRegister.X, (fcall as Node).definingSubroutine!!)
                                 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("""
                                     sta  (+) + 1
                                     sty  (+) + 2
 +                                   rol  ${'$'}ffff,x           ; modified""")
+                                asmgen.restoreRegisterLocal(CpuRegister.X)
                             } else {
                                 asmgen.assignExpressionToRegister(what.addressExpression, RegisterOrPair.AY)
                                 asmgen.out("""
@@ -774,18 +617,14 @@ internal class BuiltinFunctionsAsmGen(private val program: Program,
     }
 
     private fun translateRolRorArrayArgs(arrayvar: IdentifierReference, indexer: ArrayIndex, operation: String, dt: Char) {
-        asmgen.assignExpressionToVariable(AddressOf(arrayvar, arrayvar.position), "prog8_lib.${operation}_array_u${dt}._arg_target", DataType.UWORD, null)
-        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))
+        if(arrayvar.targetVarDecl(program)!!.datatype==DataType.UWORD) {
+            if(dt!='b')
+                throw AssemblyError("non-array var indexing requires bytes dt")
+            asmgen.assignExpressionToVariable(arrayvar, "prog8_lib.${operation}_array_u${dt}._arg_target", DataType.UWORD, null)
+        } else {
+            asmgen.assignExpressionToVariable(AddressOf(arrayvar, arrayvar.position), "prog8_lib.${operation}_array_u${dt}._arg_target", DataType.UWORD, null)
         }
+        asmgen.assignExpressionToVariable(indexer.indexExpr, "prog8_lib.${operation}_array_u${dt}._arg_index", DataType.UBYTE, null)
     }
 
     private fun funcSgn(fcall: IFunctionCall, func: FSignature, resultToStack: Boolean, resultRegister: RegisterOrPair?, scope: Subroutine?) {
@@ -825,538 +664,35 @@ internal class BuiltinFunctionsAsmGen(private val program: Program,
             }
         } 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]
-        val second = fcall.args[1]
-
-        // optimized simple case: swap two variables
-        if(first is IdentifierReference && second is IdentifierReference) {
-            val firstName = asmgen.asmVariableName(first)
-            val secondName = asmgen.asmVariableName(second)
-            val dt = first.inferType(program)
-            if(dt istype DataType.BYTE || dt istype DataType.UBYTE) {
-                asmgen.out(" ldy  $firstName |  lda  $secondName |  sta  $firstName |  sty  $secondName")
-                return
-            }
-            if(dt istype DataType.WORD || dt istype DataType.UWORD) {
-                asmgen.out("""
-                    ldy  $firstName
-                    lda  $secondName
-                    sta  $firstName
-                    sty  $secondName
-                    ldy  $firstName+1
-                    lda  $secondName+1
-                    sta  $firstName+1
-                    sty  $secondName+1
-                """)
-                return
-            }
-            if(dt istype DataType.FLOAT) {
-                asmgen.out("""
-                    lda  #<$firstName
-                    sta  P8ZP_SCRATCH_W1
-                    lda  #>$firstName
-                    sta  P8ZP_SCRATCH_W1+1
-                    lda  #<$secondName
-                    sta  P8ZP_SCRATCH_W2
-                    lda  #>$secondName
-                    sta  P8ZP_SCRATCH_W2+1
-                    jsr  floats.func_swap_f
-                """)
-                return
-            }
-        }
-
-        // optimized simple case: swap two memory locations
-        if(first is DirectMemoryRead && second is DirectMemoryRead) {
-            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
-
-            when {
-                addr1!=null && addr2!=null -> {
-                    asmgen.out("  ldy  $addr1 |  lda  $addr2 |  sta  $addr1 |  sty  $addr2")
-                    return
-                }
-                addr1!=null && name2!=null -> {
-                    asmgen.out("  ldy  $addr1 |  lda  $name2 |  sta  $addr1 |  sty  $name2")
-                    return
-                }
-                name1!=null && addr2 != null -> {
-                    asmgen.out("  ldy  $name1 |  lda  $addr2 |  sta  $name1 |  sty  $addr2")
-                    return
-                }
-                name1!=null && name2!=null -> {
-                    asmgen.out("  ldy  $name1 |  lda  $name2 |  sta  $name1 |  sty  $name2")
-                    return
-                }
-                addr1==null && addr2==null && name1==null && name2==null -> {
-                    val firstExpr = first.addressExpression as? BinaryExpression
-                    val secondExpr = second.addressExpression as? BinaryExpression
-                    if(firstExpr!=null && secondExpr!=null) {
-                        val pointerVariable = firstExpr.left as? IdentifierReference
-                        val firstOffset = firstExpr.right
-                        val secondOffset = secondExpr.right
-                        if(pointerVariable != null
-                            && pointerVariable isSameAs secondExpr.left
-                            && firstExpr.operator == "+" && secondExpr.operator == "+"
-                            && (firstOffset is NumericLiteral || firstOffset is IdentifierReference || firstOffset is TypecastExpression)
-                            && (secondOffset is NumericLiteral || secondOffset is IdentifierReference || secondOffset is TypecastExpression)
-                        ) {
-                            if(firstOffset is NumericLiteral && secondOffset is NumericLiteral) {
-                                if(firstOffset!=secondOffset) {
-                                    swapArrayValues(
-                                        DataType.UBYTE,
-                                        asmgen.asmVariableName(pointerVariable), firstOffset,
-                                        asmgen.asmVariableName(pointerVariable), secondOffset
-                                    )
-                                    return
-                                }
-                            } else if(firstOffset is TypecastExpression && secondOffset is TypecastExpression) {
-                                if(firstOffset.type in WordDatatypes && secondOffset.type in WordDatatypes) {
-                                    val firstOffsetVar = firstOffset.expression as? IdentifierReference
-                                    val secondOffsetVar = secondOffset.expression as? IdentifierReference
-                                    if(firstOffsetVar!=null && secondOffsetVar!=null) {
-                                        if(firstOffsetVar!=secondOffsetVar) {
-                                            swapArrayValues(
-                                                DataType.UBYTE,
-                                                asmgen.asmVariableName(pointerVariable), firstOffsetVar,
-                                                asmgen.asmVariableName(pointerVariable), secondOffsetVar
-                                            )
-                                            return
-                                        }
-                                    }
-                                }
-                            } else if(firstOffset is IdentifierReference || secondOffset is IdentifierReference) {
-                                throw AssemblyError("expected a typecast-to-word for index variable at ${firstOffset.position} and/or ${secondOffset.position}")
-                            }
-                        }
-                    }
-                }
-            }
-        }
-
-        if(first is ArrayIndexedExpression && second is ArrayIndexedExpression) {
-            val arrayVarName1 = asmgen.asmVariableName(first.arrayvar)
-            val arrayVarName2 = asmgen.asmVariableName(second.arrayvar)
-            val elementIDt = first.inferType(program)
-            val elementDt = elementIDt.getOrElse { throw AssemblyError("unknown dt") }
-
-            val firstNum = first.indexer.indexExpr as? NumericLiteral
-            val firstVar = first.indexer.indexExpr as? IdentifierReference
-            val secondNum = second.indexer.indexExpr as? NumericLiteral
-            val secondVar = second.indexer.indexExpr as? IdentifierReference
-
-            if(firstNum!=null && secondNum!=null) {
-                swapArrayValues(elementDt, arrayVarName1, firstNum, arrayVarName2, secondNum)
-                return
-            } else if(firstVar!=null && secondVar!=null) {
-                swapArrayValues(elementDt, arrayVarName1, firstVar, arrayVarName2, secondVar)
-                return
-            } else if(firstNum!=null && secondVar!=null) {
-                swapArrayValues(elementDt, arrayVarName1, firstNum, arrayVarName2, secondVar)
-                return
-            } else if(firstVar!=null && secondNum!=null) {
-                swapArrayValues(elementDt, arrayVarName1, firstVar, arrayVarName2, secondNum)
-                return
-            }
-        }
-
-        // all other types of swap() calls are done via a temporary variable
-
-        fun targetFromExpr(expr: Expression, datatype: DataType): AsmAssignTarget {
-            return when (expr) {
-                is IdentifierReference -> AsmAssignTarget(TargetStorageKind.VARIABLE, program, asmgen, datatype, expr.definingSubroutine, variableAsmName = asmgen.asmVariableName(expr))
-                is ArrayIndexedExpression -> AsmAssignTarget(TargetStorageKind.ARRAY, program, asmgen, datatype, expr.definingSubroutine, array = expr)
-                is DirectMemoryRead -> AsmAssignTarget(TargetStorageKind.MEMORY, program, asmgen, datatype, expr.definingSubroutine, memory = DirectMemoryWrite(expr.addressExpression, expr.position))
-                else -> throw AssemblyError("invalid expression object $expr")
-            }
-        }
-
-        when(val datatype: DataType = first.inferType(program).getOr(DataType.UNDEFINED)) {
-            in ByteDatatypes, in WordDatatypes -> {
-                asmgen.assignExpressionToVariable(first, "P8ZP_SCRATCH_W1", datatype, null)
-                asmgen.assignExpressionToVariable(second, "P8ZP_SCRATCH_W2", datatype, null)
-                val assignFirst = AsmAssignment(
-                        AsmAssignSource(SourceStorageKind.VARIABLE, program, asmgen, datatype, variableAsmName = "P8ZP_SCRATCH_W2"),
-                        targetFromExpr(first, datatype),
-                        false, program.memsizer, first.position
-                )
-                val assignSecond = AsmAssignment(
-                        AsmAssignSource(SourceStorageKind.VARIABLE, program, asmgen, datatype, variableAsmName = "P8ZP_SCRATCH_W1"),
-                        targetFromExpr(second, datatype),
-                        false, program.memsizer, second.position
-                )
-                asmgen.translateNormalAssignment(assignFirst)
-                asmgen.translateNormalAssignment(assignSecond)
-            }
-            DataType.FLOAT -> {
-                // via temp variable and FAC1
-                asmgen.assignExpressionTo(first, AsmAssignTarget(TargetStorageKind.VARIABLE, program, asmgen, DataType.FLOAT, first.definingSubroutine, "floats.tempvar_swap_float"))
-                asmgen.assignExpressionTo(second, AsmAssignTarget(TargetStorageKind.REGISTER, program, asmgen, DataType.FLOAT, null, register=RegisterOrPair.FAC1))
-                asmgen.translateNormalAssignment(
-                    AsmAssignment(
-                        AsmAssignSource(SourceStorageKind.REGISTER, program, asmgen, datatype, register = RegisterOrPair.FAC1),
-                        targetFromExpr(first, datatype),
-                        false, program.memsizer, first.position
-                    )
-                )
-                asmgen.translateNormalAssignment(
-                    AsmAssignment(
-                        AsmAssignSource(SourceStorageKind.VARIABLE, program, asmgen, datatype, "floats.tempvar_swap_float"),
-                        targetFromExpr(second, datatype),
-                        false, program.memsizer, second.position
-                    )
-                )
-            }
-            else -> throw AssemblyError("weird swap dt")
-        }
-    }
-
-    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) {
-            DataType.UBYTE, DataType.BYTE -> {
-                asmgen.out("""
-                    lda  $arrayVarName1+$index1
-                    ldy  $arrayVarName2+$index2
-                    sta  $arrayVarName2+$index2
-                    sty  $arrayVarName1+$index1
-                """)
-            }
-            DataType.UWORD, DataType.WORD -> {
-                asmgen.out("""
-                    lda  $arrayVarName1+$index1
-                    ldy  $arrayVarName2+$index2
-                    sta  $arrayVarName2+$index2
-                    sty  $arrayVarName1+$index1
-                    lda  $arrayVarName1+$index1+1
-                    ldy  $arrayVarName2+$index2+1
-                    sta  $arrayVarName2+$index2+1
-                    sty  $arrayVarName1+$index1+1
-                """)
-            }
-            DataType.FLOAT -> {
-                asmgen.out("""
-                    lda  #<(${arrayVarName1}+$index1)
-                    sta  P8ZP_SCRATCH_W1
-                    lda  #>(${arrayVarName1}+$index1)
-                    sta  P8ZP_SCRATCH_W1+1
-                    lda  #<(${arrayVarName2}+$index2)
-                    sta  P8ZP_SCRATCH_W2
-                    lda  #>(${arrayVarName2}+$index2)
-                    sta  P8ZP_SCRATCH_W2+1
-                    jsr  floats.func_swap_f
-                """)
-            }
-            else -> throw AssemblyError("invalid aray elt type")
-        }
-    }
-
-    private fun swapArrayValues(elementDt: DataType, arrayVarName1: String, indexName1: IdentifierReference, arrayVarName2: String, indexName2: IdentifierReference) {
-        val idxAsmName1 = asmgen.asmVariableName(indexName1)
-        val idxAsmName2 = asmgen.asmVariableName(indexName2)
-        when(elementDt) {
-            DataType.UBYTE, DataType.BYTE -> {
-                asmgen.out("""
-                    stx  P8ZP_SCRATCH_REG
-                    ldx  $idxAsmName1
-                    ldy  $idxAsmName2
-                    lda  $arrayVarName1,x
-                    pha
-                    lda  $arrayVarName2,y
-                    sta  $arrayVarName1,x
-                    pla
-                    sta  $arrayVarName2,y
-                    ldx  P8ZP_SCRATCH_REG
-                """)
-            }
-            DataType.UWORD, DataType.WORD -> {
-                asmgen.out("""
-                    stx  P8ZP_SCRATCH_REG
-                    lda  $idxAsmName1
-                    asl  a
-                    tax
-                    lda  $idxAsmName2
-                    asl  a
-                    tay
-                    lda  $arrayVarName1,x
-                    pha
-                    lda  $arrayVarName2,y
-                    sta  $arrayVarName1,x
-                    pla
-                    sta  $arrayVarName2,y
-                    lda  $arrayVarName1+1,x
-                    pha
-                    lda  $arrayVarName2+1,y
-                    sta  $arrayVarName1+1,x
-                    pla
-                    sta  $arrayVarName2+1,y
-                    ldx  P8ZP_SCRATCH_REG
-                """)
-            }
-            DataType.FLOAT -> {
-                asmgen.out("""
-                    lda  #>$arrayVarName1
-                    sta  P8ZP_SCRATCH_W1+1
-                    lda  $idxAsmName1
-                    asl  a
-                    asl  a
-                    clc
-                    adc  $idxAsmName1
-                    adc  #<$arrayVarName1
-                    sta  P8ZP_SCRATCH_W1
-                    bcc  +
-                    inc  P8ZP_SCRATCH_W1+1
-+                   lda  #>$arrayVarName2
-                    sta  P8ZP_SCRATCH_W2+1
-                    lda  $idxAsmName2
-                    asl  a
-                    asl  a
-                    clc
-                    adc  $idxAsmName2
-                    adc  #<$arrayVarName2
-                    sta  P8ZP_SCRATCH_W2
-                    bcc  +
-                    inc  P8ZP_SCRATCH_W2+1
-+                   jsr  floats.func_swap_f                                   
-                """)
-            }
-            else -> throw AssemblyError("invalid aray elt type")
-        }
-    }
-
-    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) {
-            DataType.UBYTE, DataType.BYTE -> {
-                asmgen.out("""
-                    lda  $arrayVarName1 + $index1
-                    pha
-                    ldy  $idxAsmName2
-                    lda  $arrayVarName2,y
-                    sta  $arrayVarName1 + $index1
-                    pla
-                    sta  $arrayVarName2,y
-                """)
-            }
-            DataType.UWORD, DataType.WORD -> {
-                asmgen.out("""
-                    lda  $arrayVarName1 + $index1
-                    pha
-                    lda  $idxAsmName2
-                    asl  a
-                    tay
-                    lda  $arrayVarName2,y
-                    sta  $arrayVarName1 + $index1
-                    pla
-                    sta  $arrayVarName2,y
-                    lda  $arrayVarName1 + $index1+1
-                    pha
-                    lda  $arrayVarName2+1,y
-                    sta  $arrayVarName1 + $index1+1
-                    pla
-                    sta  $arrayVarName2+1,y
-                """)
-            }
-            DataType.FLOAT -> {
-                asmgen.out("""
-                    lda  #<(${arrayVarName1}+$index1)
-                    sta  P8ZP_SCRATCH_W1
-                    lda  #>(${arrayVarName1}+$index1)
-                    sta  P8ZP_SCRATCH_W1+1
-                    lda  #>$arrayVarName1
-                    sta  P8ZP_SCRATCH_W1+1
-                    lda  $idxAsmName2
-                    asl  a
-                    asl  a
-                    clc
-                    adc  $idxAsmName2
-                    adc  #<$arrayVarName1
-                    sta  P8ZP_SCRATCH_W1
-                    bcc  +
-                    inc  P8ZP_SCRATCH_W1+1
-+                   jsr  floats.func_swap_f
-                """)
-            }
-            else -> throw AssemblyError("invalid aray elt type")
-        }
-    }
-
-    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) {
-            DataType.UBYTE, DataType.BYTE -> {
-                asmgen.out("""
-                    lda  $arrayVarName2 + $index2
-                    pha
-                    ldy  $idxAsmName1
-                    lda  $arrayVarName1,y
-                    sta  $arrayVarName2 + $index2
-                    pla
-                    sta  $arrayVarName1,y
-                """)
-            }
-            DataType.UWORD, DataType.WORD -> {
-                asmgen.out("""
-                    lda  $arrayVarName2 + $index2
-                    pha
-                    lda  $idxAsmName1
-                    asl  a
-                    tay
-                    lda  $arrayVarName1,y
-                    sta  $arrayVarName2 + $index2
-                    pla
-                    sta  $arrayVarName1,y
-                    lda  $arrayVarName2 + $index2+1
-                    pha
-                    lda  $arrayVarName1+1,y
-                    sta  $arrayVarName2 + $index2+1
-                    pla
-                    sta  $arrayVarName1+1,y
-                """)
-            }
-            DataType.FLOAT -> {
-                asmgen.out("""
-                    lda  #>$arrayVarName1
-                    sta  P8ZP_SCRATCH_W1+1
-                    lda  $idxAsmName1
-                    asl  a
-                    asl  a
-                    clc
-                    adc  $idxAsmName1
-                    adc  #<$arrayVarName1
-                    sta  P8ZP_SCRATCH_W1
-                    bcc  +
-                    inc  P8ZP_SCRATCH_W1+1
-+                   lda  #<(${arrayVarName2}+$index2)
-                    sta  P8ZP_SCRATCH_W2
-                    lda  #>(${arrayVarName2}+$index2)
-                    sta  P8ZP_SCRATCH_W2+1
-                    jsr  floats.func_swap_f
-                """)
-            }
-            else -> throw AssemblyError("invalid aray elt type")
-        }
-    }
-
     private fun funcAbs(fcall: IFunctionCall, func: FSignature, resultToStack: Boolean, resultRegister: RegisterOrPair?, scope: Subroutine?) {
         translateArguments(fcall.args, func, scope)
         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)
         }
     }
 
@@ -1524,12 +860,12 @@ internal class BuiltinFunctionsAsmGen(private val program: Program,
             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 NumericLiteral || fcall.args[0] is IdentifierReference)
+            var needAsave = asmgen.needAsaveForExpr(fcall.args[0])
             if(!needAsave) {
                 val mr0 = fcall.args[0] as? DirectMemoryRead
                 val mr1 = fcall.args[1] as? DirectMemoryRead
                 if (mr0 != null)
-                    needAsave = mr0.addressExpression !is NumericLiteral && mr0.addressExpression !is IdentifierReference
+                    needAsave =  mr0.addressExpression !is NumericLiteral && mr0.addressExpression !is IdentifierReference
                 if (mr1 != null)
                     needAsave = needAsave or (mr1.addressExpression !is NumericLiteral && mr1.addressExpression !is IdentifierReference)
             }
@@ -1688,8 +1024,11 @@ internal class BuiltinFunctionsAsmGen(private val program: Program,
     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
@@ -1701,7 +1040,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program,
 
     private fun translateArguments(args: MutableList<Expression>, signature: FSignature, scope: Subroutine?) {
         val callConv = signature.callConvention(args.map {
-            it.inferType(program).getOrElse { throw AssemblyError("unknown dt")}
+            it.inferType(program).getOrElse { throw AssemblyError("unknown dt") }
         })
 
         fun getSourceForFloat(value: Expression): AsmAssignSource {
@@ -1717,7 +1056,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program,
                     if(scope==null)
                         throw AssemblyError("cannot use float arguments outside of a subroutine scope")
 
-                    allocations.subroutineExtra(scope).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

@@ -1,14 +1,8 @@
 package prog8.codegen.cpu6502
 
 import prog8.ast.Program
-import prog8.ast.base.*
 import prog8.ast.expressions.*
-import prog8.ast.statements.BuiltinFunctionPlaceholder
-import prog8.ast.statements.Subroutine
-import prog8.ast.toHex
-import prog8.compilerinterface.AssemblyError
-import prog8.compilerinterface.BuiltinFunctions
-import prog8.compilerinterface.CpuType
+import prog8.code.core.*
 import kotlin.math.absoluteValue
 
 internal class ExpressionsAsmGen(private val program: Program,
@@ -39,7 +33,7 @@ internal class ExpressionsAsmGen(private val program: Program,
             is NumericLiteral -> translateExpression(expression)
             is IdentifierReference -> translateExpression(expression)
             is FunctionCallExpression -> translateFunctionCallResultOntoStack(expression)
-            is PipeExpression -> asmgen.translatePipeExpression(expression.expressions,  expression,false, true)
+            is BuiltinFunctionCall -> asmgen.translateBuiltinFunctionCallExpression(expression, true, null)
             is ContainmentCheck -> throw AssemblyError("containment check as complex expression value is not supported")
             is ArrayLiteral, is StringLiteral -> throw AssemblyError("no asm gen for string/array literal value assignment - should have been replaced by a variable")
             is RangeExpression -> throw AssemblyError("range expression should have been changed into array values")
@@ -51,96 +45,90 @@ internal class ExpressionsAsmGen(private val program: Program,
     private fun translateFunctionCallResultOntoStack(call: FunctionCallExpression) {
         // only for use in nested expression evaluation
 
-        val sub = call.target.targetStatement(program)
-        if(sub is BuiltinFunctionPlaceholder) {
-            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 -> {}
             }
         }
     }
@@ -148,7 +136,7 @@ internal class ExpressionsAsmGen(private val program: Program,
     private fun translateExpression(typecast: TypecastExpression) {
         translateExpressionInternal(typecast.expression)
         when(typecast.expression.inferType(program).getOr(DataType.UNDEFINED)) {
-            DataType.UBYTE -> {
+            DataType.UBYTE, DataType.BOOL -> {
                 when(typecast.type) {
                     DataType.UBYTE, DataType.BYTE -> {}
                     DataType.UWORD, DataType.WORD -> {
@@ -544,8 +532,8 @@ internal class ExpressionsAsmGen(private val program: Program,
             }
             in ComparisonOperators -> {
                 if(leftDt in NumericDatatypes && rightDt in NumericDatatypes) {
-                    val rightVal = expr.right.constValue(program)?.number?.toInt()
-                    if(rightVal==0)
+                    val rightVal = expr.right.constValue(program)?.number
+                    if(rightVal==0.0)
                         return translateComparisonWithZero(expr.left, leftDt, expr.operator)
                 }
             }
@@ -572,6 +560,42 @@ internal class ExpressionsAsmGen(private val program: Program,
     }
 
     private fun translateComparisonWithZero(expr: Expression, dt: DataType, operator: String) {
+        if(expr.isSimple) {
+            if(operator=="!=") {
+                when (dt) {
+                    in ByteDatatypes -> {
+                        asmgen.assignExpressionToRegister(expr, RegisterOrPair.A, dt == DataType.BYTE)
+                        asmgen.out("""
+                            beq  +
+                            lda  #1
++                           sta  P8ESTACK_LO,x
+                            dex""")
+                        return
+                    }
+                    in WordDatatypes -> {
+                        asmgen.assignExpressionToRegister(expr, RegisterOrPair.AY, dt == DataType.WORD)
+                        asmgen.out("""
+                            sty  P8ZP_SCRATCH_B1 
+                            ora  P8ZP_SCRATCH_B1
+                            beq  +
+                            lda  #1
++                           sta  P8ESTACK_LO,x
+                            dex""")
+                        return
+                    }
+                    DataType.FLOAT -> {
+                        asmgen.assignExpressionToRegister(expr, RegisterOrPair.FAC1, true)
+                        asmgen.out("""
+                            jsr  floats.SIGN
+                            sta  P8ESTACK_LO,x
+                            dex""")
+                        return
+                    }
+                    else -> {}
+                }
+            }
+            /* operator == is not worth it to special case, the code is mostly larger */
+        }
         translateExpressionInternal(expr)
         when(operator) {
             "==" -> {
@@ -676,13 +700,6 @@ internal class ExpressionsAsmGen(private val program: Program,
                     else -> throw AssemblyError("weird type")
                 }
             }
-            "not" -> {
-                when(type) {
-                    in ByteDatatypes -> asmgen.out("  jsr  prog8_lib.not_byte")
-                    in WordDatatypes -> asmgen.out("  jsr  prog8_lib.not_word")
-                    else -> throw AssemblyError("weird type")
-                }
-            }
             else -> throw AssemblyError("invalid prefix operator ${expr.operator}")
         }
     }
@@ -693,6 +710,25 @@ internal class ExpressionsAsmGen(private val program: Program,
             throw AssemblyError("unknown dt")
         val elementDt = elementIDt.getOr(DataType.UNDEFINED)
         val arrayVarName = asmgen.asmVariableName(arrayExpr.arrayvar)
+
+        val arrayVarDecl = arrayExpr.arrayvar.targetVarDecl(program)!!
+        if(arrayVarDecl.datatype==DataType.UWORD) {
+            // indexing a pointer var instead of a real array or string
+            if(elementDt !in ByteDatatypes)
+                throw AssemblyError("non-array var indexing requires bytes dt")
+            if(arrayExpr.inferType(program) isnot DataType.UBYTE)
+                throw AssemblyError("non-array var indexing requires bytes index")
+            asmgen.loadScaledArrayIndexIntoRegister(arrayExpr, elementDt, CpuRegister.Y)
+            if(asmgen.isZpVar(arrayExpr.arrayvar)) {
+                asmgen.out("  lda  ($arrayVarName),y")
+            } else {
+                asmgen.out("  lda  $arrayVarName |  sta  P8ZP_SCRATCH_W1 |  lda  $arrayVarName+1 |  sta  P8ZP_SCRATCH_W1+1")
+                asmgen.out("  lda  (P8ZP_SCRATCH_W1),y")
+            }
+            asmgen.out("  sta  P8ESTACK_LO,x |  dex")
+            return
+        }
+
         val constIndexNum = arrayExpr.indexer.constIndex()
         if(constIndexNum!=null) {
             val indexValue = constIndexNum * program.memsizer.memorySize(elementDt)
@@ -736,7 +772,6 @@ internal class ExpressionsAsmGen(private val program: Program,
 
     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")
             "%" -> {
@@ -769,16 +804,12 @@ internal class ExpressionsAsmGen(private val program: Program,
             "&" -> asmgen.out("  jsr  prog8_lib.bitand_b")
             "^" -> asmgen.out("  jsr  prog8_lib.bitxor_b")
             "|" -> asmgen.out("  jsr  prog8_lib.bitor_b")
-            "and" -> asmgen.out("  jsr  prog8_lib.and_b")
-            "or" -> asmgen.out("  jsr  prog8_lib.or_b")
-            "xor" -> asmgen.out("  jsr  prog8_lib.xor_b")
             else -> throw AssemblyError("invalid operator $operator")
         }
     }
 
     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")
             "%" -> {
@@ -804,16 +835,12 @@ internal class ExpressionsAsmGen(private val program: Program,
             "&" -> 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")
-            "or" -> asmgen.out("  jsr  prog8_lib.or_w")
-            "xor" -> asmgen.out("  jsr  prog8_lib.xor_w")
             else -> throw AssemblyError("invalid operator $operator")
         }
     }
 
     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")
@@ -824,7 +851,7 @@ internal class ExpressionsAsmGen(private val program: Program,
             ">=" -> asmgen.out("  jsr  floats.greatereq_f")
             "==" -> asmgen.out("  jsr  floats.equal_f")
             "!=" -> asmgen.out("  jsr  floats.notequal_f")
-            "%", "<<", ">>", "&", "^", "|", "and", "or", "xor" -> throw AssemblyError("requires integer datatype")
+            "%", "<<", ">>", "&", "^", "|" -> throw AssemblyError("requires integer datatype")
             else -> throw AssemblyError("invalid operator $operator")
         }
     }

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

@@ -2,15 +2,10 @@ 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.RangeExpression
 import prog8.ast.statements.ForLoop
-import prog8.ast.toHex
-import prog8.compilerinterface.AssemblyError
-import prog8.compilerinterface.Zeropage
+import prog8.code.core.*
 import kotlin.math.absoluteValue
 
 internal class ForLoopsAsmGen(private val program: Program, private val asmgen: AsmGen, private val zeropage: Zeropage) {
@@ -36,10 +31,10 @@ internal class ForLoopsAsmGen(private val program: Program, private val asmgen:
     }
 
     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")
-        val modifiedLabel2 = asmgen.makeLabel("for_modifiedb")
+        val loopLabel = program.makeLabel("for_loop")
+        val endLabel = program.makeLabel("for_end")
+        val modifiedLabel = program.makeLabel("for_modified")
+        val modifiedLabel2 = program.makeLabel("for_modifiedb")
         asmgen.loopEndLabels.push(endLabel)
         val stepsize=range.step.constValue(program)!!.number.toInt()
 
@@ -243,8 +238,8 @@ $endLabel""")
     }
 
     private fun translateForOverIterableVar(stmt: ForLoop, iterableDt: DataType, ident: IdentifierReference) {
-        val loopLabel = asmgen.makeLabel("for_loop")
-        val endLabel = asmgen.makeLabel("for_end")
+        val loopLabel = program.makeLabel("for_loop")
+        val endLabel = program.makeLabel("for_end")
         asmgen.loopEndLabels.push(endLabel)
         val iterableName = asmgen.asmVariableName(ident)
         val decl = ident.targetVarDecl(program)!!
@@ -268,7 +263,7 @@ $endLabel""")
             }
             DataType.ARRAY_UB, DataType.ARRAY_B -> {
                 val length = decl.arraysize!!.constIndex()!!
-                val indexVar = asmgen.makeLabel("for_index")
+                val indexVar = program.makeLabel("for_index")
                 asmgen.out("""
                     ldy  #0
 $loopLabel          sty  $indexVar
@@ -292,7 +287,7 @@ $loopLabel          sty  $indexVar
                 }
                 if(length>=16) {
                     // allocate index var on ZP if possible
-                    val result = zeropage.allocate(listOf(indexVar), DataType.UBYTE, stmt.definingScope, null, null, stmt.position, asmgen.errors)
+                    val result = zeropage.allocate(listOf(indexVar), DataType.UBYTE, null, stmt.position, asmgen.errors)
                     result.fold(
                         success = { (address,_)-> asmgen.out("""$indexVar = $address  ; auto zp UBYTE""") },
                         failure = { asmgen.out("$indexVar    .byte  0") }
@@ -304,7 +299,7 @@ $loopLabel          sty  $indexVar
             }
             DataType.ARRAY_W, DataType.ARRAY_UW -> {
                 val length = decl.arraysize!!.constIndex()!! * 2
-                val indexVar = asmgen.makeLabel("for_index")
+                val indexVar = program.makeLabel("for_index")
                 val loopvarName = asmgen.asmVariableName(stmt.loopVar)
                 asmgen.out("""
                     ldy  #0
@@ -333,7 +328,7 @@ $loopLabel          sty  $indexVar
                 }
                 if(length>=16) {
                     // allocate index var on ZP if possible
-                    val result = zeropage.allocate(listOf(indexVar), DataType.UBYTE, stmt.definingScope, null, null, stmt.position, asmgen.errors)
+                    val result = zeropage.allocate(listOf(indexVar), DataType.UBYTE, null, stmt.position, asmgen.errors)
                     result.fold(
                         success = { (address,_)-> asmgen.out("""$indexVar = $address  ; auto zp UBYTE""") },
                         failure = { asmgen.out("$indexVar    .byte  0") }
@@ -364,8 +359,8 @@ $loopLabel          sty  $indexVar
         }
 
         // not one of the easy cases, generate more complex code...
-        val loopLabel = asmgen.makeLabel("for_loop")
-        val endLabel = asmgen.makeLabel("for_end")
+        val loopLabel = program.makeLabel("for_loop")
+        val endLabel = program.makeLabel("for_end")
         asmgen.loopEndLabels.push(endLabel)
         when(iterableDt) {
             DataType.ARRAY_B, DataType.ARRAY_UB -> {
@@ -476,8 +471,8 @@ $loopLabel""")
     }
 
     private fun translateForSimpleByteRangeAsc(stmt: ForLoop, range: IntProgression) {
-        val loopLabel = asmgen.makeLabel("for_loop")
-        val endLabel = asmgen.makeLabel("for_end")
+        val loopLabel = program.makeLabel("for_loop")
+        val endLabel = program.makeLabel("for_end")
         asmgen.loopEndLabels.push(endLabel)
         val varname = asmgen.asmVariableName(stmt.loopVar)
         asmgen.out("""
@@ -502,8 +497,8 @@ $endLabel""")
     }
 
     private fun translateForSimpleByteRangeDesc(stmt: ForLoop, range: IntProgression) {
-        val loopLabel = asmgen.makeLabel("for_loop")
-        val endLabel = asmgen.makeLabel("for_end")
+        val loopLabel = program.makeLabel("for_loop")
+        val endLabel = program.makeLabel("for_end")
         asmgen.loopEndLabels.push(endLabel)
         val varname = asmgen.asmVariableName(stmt.loopVar)
         asmgen.out("""
@@ -539,8 +534,8 @@ $endLabel""")
     }
 
     private fun translateForSimpleWordRangeAsc(stmt: ForLoop, range: IntProgression) {
-        val loopLabel = asmgen.makeLabel("for_loop")
-        val endLabel = asmgen.makeLabel("for_end")
+        val loopLabel = program.makeLabel("for_loop")
+        val endLabel = program.makeLabel("for_end")
         asmgen.loopEndLabels.push(endLabel)
         val varname = asmgen.asmVariableName(stmt.loopVar)
         asmgen.out("""
@@ -566,8 +561,8 @@ $loopLabel""")
     }
 
     private fun translateForSimpleWordRangeDesc(stmt: ForLoop, range: IntProgression) {
-        val loopLabel = asmgen.makeLabel("for_loop")
-        val endLabel = asmgen.makeLabel("for_end")
+        val loopLabel = program.makeLabel("for_loop")
+        val endLabel = program.makeLabel("for_end")
         asmgen.loopEndLabels.push(endLabel)
         val varname = asmgen.asmVariableName(stmt.loopVar)
         asmgen.out("""

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

@@ -3,23 +3,21 @@ package prog8.codegen.cpu6502
 import prog8.ast.IFunctionCall
 import prog8.ast.Node
 import prog8.ast.Program
-import prog8.ast.base.*
 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.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
-import prog8.compilerinterface.AssemblyError
-import prog8.compilerinterface.CpuType
 
 
 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)
@@ -38,7 +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)
@@ -60,7 +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)
@@ -113,14 +111,16 @@ internal class FunctionCallAsmGen(private val program: Program, private val asmg
                 } 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)
+                    if(asmgen.needAsaveForExpr(call.args[1]))
                         asmgen.out("  pha")
                     argumentViaRegister(sub, IndexedValue(1, sub.parameters[1]), call.args[1], RegisterOrPair.Y)
-                    if(!call.args[1].isSimple)
+                    if(asmgen.needAsaveForExpr(call.args[1]))
                         asmgen.out("  pla")
                 }
             } else {
-                argumentsViaVariables(sub, call)
+                // arguments via variables
+                for(arg in sub.parameters.withIndex().zip(call.args))
+                    argumentViaVariable(sub, arg.first.value, arg.second)
             }
             asmgen.out("  jsr  $subAsmName")
         }
@@ -128,77 +128,14 @@ internal class FunctionCallAsmGen(private val program: Program, private val asmg
         // remember: dealing with the X register and/or dealing with return values is the responsibility of the caller
     }
 
-    internal fun translateUnaryFunctionCallWithArgSource(target: IdentifierReference, arg: AsmAssignSource, isStatement: Boolean, scope: Subroutine): DataType {
-        when(val targetStmt = target.targetStatement(program)!!) {
-            is BuiltinFunctionPlaceholder -> {
-                return if(isStatement) {
-                    asmgen.translateBuiltinFunctionCallStatement(targetStmt.name, listOf(arg), scope)
-                    DataType.UNDEFINED
-                } else {
-                    asmgen.translateBuiltinFunctionCallExpression(targetStmt.name, listOf(arg), scope)
-                }
-            }
-            is Subroutine -> {
-                val argDt = targetStmt.parameters.single().type
-                if(targetStmt.isAsmSubroutine) {
-                    // argument via registers
-                    val argRegister = targetStmt.asmParameterRegisters.single().registerOrPair!!
-                    val assignArgument = AsmAssignment(
-                        arg,
-                        AsmAssignTarget.fromRegisters(argRegister, argDt in SignedDatatypes, scope, program, asmgen),
-                        false, program.memsizer, target.position
-                    )
-                    asmgen.translateNormalAssignment(assignArgument)
-                } else {
-                    val assignArgument: AsmAssignment =
-                        if(optimizeIntArgsViaRegisters(targetStmt)) {
-                            // argument goes via registers as optimization
-                            val paramReg: RegisterOrPair = when(argDt) {
-                                in ByteDatatypes -> RegisterOrPair.A
-                                in WordDatatypes -> RegisterOrPair.AY
-                                DataType.FLOAT -> RegisterOrPair.FAC1
-                                else -> throw AssemblyError("invalid dt")
-                            }
-                            AsmAssignment(
-                                arg,
-                                AsmAssignTarget(TargetStorageKind.REGISTER, program, asmgen, argDt, scope, register = paramReg),
-                                false, program.memsizer, target.position
-                            )
-                        } else {
-                            // arg goes via parameter variable
-                            val argVarName = asmgen.asmVariableName(targetStmt.scopedName + targetStmt.parameters.single().name)
-                            AsmAssignment(
-                                arg,
-                                AsmAssignTarget(TargetStorageKind.VARIABLE, program, asmgen, argDt, scope, argVarName),
-                                false, program.memsizer, target.position
-                            )
-                        }
-                    asmgen.translateNormalAssignment(assignArgument)
-                }
-                if(targetStmt.shouldSaveX())
-                    asmgen.saveRegisterLocal(CpuRegister.X, scope)
-                asmgen.out("  jsr  ${asmgen.asmSymbolName(target)}")
-                if(targetStmt.shouldSaveX())
-                    asmgen.restoreRegisterLocal(CpuRegister.X)
-                return if(isStatement) DataType.UNDEFINED else targetStmt.returntypes.single()
-            }
-            else -> throw AssemblyError("invalid call target")
-        }
-    }
-
-    private fun argumentsViaVariables(sub: Subroutine, call: IFunctionCall) {
-        for(arg in sub.parameters.withIndex().zip(call.args))
-            argumentViaVariable(sub, arg.first.value, 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)
@@ -207,129 +144,24 @@ 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.searchParameter(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: SubroutineParameter, value: Expression) {

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

@@ -1,12 +1,10 @@
 package prog8.codegen.cpu6502
 
 import prog8.ast.Program
-import prog8.ast.base.*
 import prog8.ast.expressions.IdentifierReference
 import prog8.ast.expressions.NumericLiteral
 import prog8.ast.statements.PostIncrDecr
-import prog8.ast.toHex
-import prog8.compilerinterface.AssemblyError
+import prog8.code.core.*
 
 
 internal class PostIncrDecrAsmGen(private val program: Program, private val asmgen: AsmGen) {

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

@@ -1,15 +1,12 @@
 package prog8.codegen.cpu6502
 
-import prog8.ast.INameScope
 import prog8.ast.Program
-import prog8.ast.antlr.escape
-import prog8.ast.base.*
-import prog8.ast.expressions.*
 import prog8.ast.statements.*
-import prog8.ast.toHex
+import prog8.code.*
+import prog8.code.core.*
 import prog8.codegen.cpu6502.assignment.AsmAssignTarget
 import prog8.codegen.cpu6502.assignment.TargetStorageKind
-import prog8.compilerinterface.*
+import prog8.compiler.CallGraph
 import java.time.LocalDate
 import java.time.LocalDateTime
 import kotlin.math.absoluteValue
@@ -24,9 +21,9 @@ import kotlin.math.absoluteValue
  */
 internal class ProgramAndVarsGen(
     val program: Program,
-    val variables: IVariablesAndConsts,
     val options: CompilationOptions,
     val errors: IErrorReporter,
+    private val symboltable: SymbolTable,
     private val functioncallAsmGen: FunctionCallAsmGen,
     private val asmgen: AsmGen,
     private val allocator: VariableAllocator,
@@ -40,8 +37,6 @@ internal class ProgramAndVarsGen(
         val allInitializers = blockVariableInitializers.asSequence().flatMap { it.value }
         require(allInitializers.all { it.origin==AssignmentOrigin.VARINIT }) {"all block-level assignments must be a variable initializer"}
 
-        allocator.allocateZeropageVariables()
-
         header()
         val allBlocks = program.allBlocks
         if(allBlocks.first().name != "main")
@@ -69,45 +64,61 @@ internal class ProgramAndVarsGen(
         asmgen.out("")
         asmgen.out(".cpu  '$cpu'\n.enc  'none'\n")
 
-        program.actualLoadAddress = program.definedLoadAddress
-        if (program.actualLoadAddress == 0u)   // fix load address
-            program.actualLoadAddress = if (options.launcher == LauncherType.BASIC)
-                compTarget.machine.BASIC_LOAD_ADDRESS else compTarget.machine.RAW_LOAD_ADDRESS
-
         // 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(".weak")   // hack to allow user to override the following two with command line redefinition (however, just use '-esa' command line option instead!)
         asmgen.out("P8ESTACK_LO = ${compTarget.machine.ESTACK_LO.toHex()}")
         asmgen.out("P8ESTACK_HI = ${compTarget.machine.ESTACK_HI.toHex()}")
+        asmgen.out(".endweak")
 
-        when {
-            options.launcher == LauncherType.BASIC -> {
-                if (program.actualLoadAddress != options.compTarget.machine.BASIC_LOAD_ADDRESS)
-                    throw AssemblyError("BASIC output must have correct load address")
-                asmgen.out("; ---- basic program with sys call ----")
-                asmgen.out("* = ${program.actualLoadAddress.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  ${compTarget.name}.init_system_phase2")
+        if(options.symbolDefs.isNotEmpty()) {
+            asmgen.out("; -- user supplied symbols on the command line")
+            for((name, value) in options.symbolDefs) {
+                asmgen.out("$name = $value")
             }
-            options.output == OutputType.PRG -> {
-                asmgen.out("; ---- program without basic sys call ----")
-                asmgen.out("* = ${program.actualLoadAddress.toHex()}\n")
-                if(!options.noSysInit)
-                    asmgen.out("  jsr  ${compTarget.name}.init_system")
-                asmgen.out("  jsr  ${compTarget.name}.init_system_phase2")
-            }
-            options.output == OutputType.RAW -> {
+        }
+
+        when(options.output) {
+            OutputType.RAW -> {
                 asmgen.out("; ---- raw assembler program ----")
-                asmgen.out("* = ${program.actualLoadAddress.toHex()}\n")
+                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")
             }
         }
 
@@ -125,9 +136,24 @@ internal class ProgramAndVarsGen(
             "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 |  rts")
+                asmgen.out("  jsr  main.start")
+                asmgen.out("  jmp  ${compTarget.name}.cleanup_at_exit")
+            }
+            "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")
             }
-            "c64" -> asmgen.out("  jsr  main.start |  lda  #31 |  sta  $01 |  rts")
             else -> asmgen.jmp("main.start")
         }
     }
@@ -169,13 +195,10 @@ internal class ProgramAndVarsGen(
         }
 
         asmgen.out("${block.name}\t" + (if("force_output" in block.options()) ".block\n" else ".proc\n"))
-
         asmgen.outputSourceLine(block)
 
-        zeropagevars2asm(block)
-        memdefsAndConsts2asm(block)
+        createBlockVariables(block)
         asmsubs2asm(block.statements)
-        nonZpVariables2asm(block)
 
         asmgen.out("")
         asmgen.out("; subroutines in this block")
@@ -201,6 +224,34 @@ internal class ProgramAndVarsGen(
         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
 
@@ -229,8 +280,24 @@ internal class ProgramAndVarsGen(
         } else {
             // regular subroutine
             asmgen.out("${sub.name}\t.proc")
-            zeropagevars2asm(sub)
-            memdefsAndConsts2asm(sub)
+
+            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
@@ -262,7 +329,7 @@ internal class ProgramAndVarsGen(
             }
 
             asmgen.out("; variables")
-            val asmGenInfo = allocator.subroutineExtra(sub)
+            val asmGenInfo = asmgen.subroutineExtra(sub)
             for((dt, name, addr) in asmGenInfo.extraVars) {
                 if(addr!=null)
                     asmgen.out("$name = $addr")
@@ -282,7 +349,13 @@ internal class ProgramAndVarsGen(
                 asmgen.out("$subroutineFloatEvalResultVar1    .byte  0,0,0,0,0")
             if(asmGenInfo.usedFloatEvalResultVar2)
                 asmgen.out("$subroutineFloatEvalResultVar2    .byte  0,0,0,0,0")
-            nonZpVariables2asm(sub)
+
+            // 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")
         }
     }
@@ -298,12 +371,12 @@ internal class ProgramAndVarsGen(
         }
 
         // string and array variables in zeropage that have initializer value, should be initialized
-        val stringVarsWithInitInZp = allocator.zeropageVars.filter { it.value.dt==DataType.STR && it.value.initialStringValue!=null }
-        val arrayVarsWithInitInZp = allocator.zeropageVars.filter { it.value.dt in ArrayDatatypes && it.value.initialArrayValue!=null }
+        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.key)
+                val name = asmgen.asmVariableName(it.name)
                 asmgen.out("""
                     lda  #<${name}
                     ldy  #>${name}
@@ -314,8 +387,8 @@ internal class ProgramAndVarsGen(
                     jsr  prog8_lib.strcpy""")
             }
             arrayVarsWithInitInZp.forEach {
-                val size = it.value.size
-                val name = asmgen.asmVariableName(it.key)
+                val size = it.alloc.size
+                val name = asmgen.asmVariableName(it.name)
                 asmgen.out("""
                     lda  #<${name}_init_value
                     ldy  #>${name}_init_value
@@ -333,14 +406,13 @@ internal class ProgramAndVarsGen(
         }
 
         stringVarsWithInitInZp.forEach {
-            val varname = asmgen.asmVariableName(it.key)+"_init_value"
-            val stringvalue = it.value.initialStringValue!!
-            outputStringvar(varname, it.value.dt, stringvalue.encoding, stringvalue.value)
+            val varname = asmgen.asmVariableName(it.name)+"_init_value"
+            outputStringvar(varname, it.value.second, it.value.first)
         }
 
         arrayVarsWithInitInZp.forEach {
-            val varname = asmgen.asmVariableName(it.key)+"_init_value"
-            arrayVariable2asm(varname, it.value.dt, it.value.initialArrayValue!!, null)
+            val varname = asmgen.asmVariableName(it.name)+"_init_value"
+            arrayVariable2asm(varname, it.alloc.dt, it.value, null)
         }
 
         asmgen.out("""+       tsx
@@ -350,8 +422,42 @@ internal class ProgramAndVarsGen(
                     clc""")
     }
 
-    private fun zeropagevars2asm(scope: INameScope) {
-        val zpVariables = allocator.zeropageVars.filter { it.value.originalScope==scope }
+    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
@@ -359,70 +465,52 @@ internal class ProgramAndVarsGen(
         }
     }
 
-    private fun nonZpVariables2asm(block: Block) {
-        val variables = variables.blockVars[block]?.filter { !allocator.isZpVar(it.scopedname) } ?: emptyList()
-        nonZpVariables2asm(variables)
-    }
-
-    private fun nonZpVariables2asm(sub: Subroutine) {
-        val variables = variables.subroutineVars[sub]?.filter { !allocator.isZpVar(it.scopedname) } ?: emptyList()
-        nonZpVariables2asm(variables)
-    }
-
-    private fun nonZpVariables2asm(variables: List<IVariablesAndConsts.StaticVariable>) {
+    private fun nonZpVariables2asm(variables: List<StStaticVariable>) {
         asmgen.out("")
         asmgen.out("; non-zeropage variables")
-        val (stringvars, othervars) = variables.partition { it.type==DataType.STR }
+        val (stringvars, othervars) = variables.partition { it.dt==DataType.STR }
         stringvars.forEach {
-            val stringvalue = it.initialValue as StringLiteral
-            outputStringvar(it.scopedname.last(), it.type, stringvalue.encoding, stringvalue.value)
+            outputStringvar(it.name, it.initialStringValue!!.second, it.initialStringValue!!.first)
         }
         othervars.sortedBy { it.type }.forEach {
             staticVariable2asm(it)
         }
     }
 
-    private fun staticVariable2asm(variable: IVariablesAndConsts.StaticVariable) {
-        val name = variable.scopedname.last()
-        val value = variable.initialValue
-        val staticValue: Number =
-            if(value!=null) {
-                if(value is NumericLiteral) {
-                    if(value.type== DataType.FLOAT)
-                        value.number
-                    else
-                        value.number.toInt()
-                } else {
-                    if(variable.type in NumericDatatypes)
-                        throw AssemblyError("can only deal with constant numeric values for global vars")
-                    else 0
-                }
+    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.type) {
-            DataType.UBYTE -> asmgen.out("$name\t.byte  ${staticValue.toHex()}")
-            DataType.BYTE -> asmgen.out("$name\t.char  $staticValue")
-            DataType.UWORD -> asmgen.out("$name\t.word  ${staticValue.toHex()}")
-            DataType.WORD -> asmgen.out("$name\t.sint  $staticValue")
+        when (variable.dt) {
+            DataType.UBYTE -> asmgen.out("$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  $initialValue")
             DataType.FLOAT -> {
-                if(staticValue==0) {
+                if(initialValue==0) {
                     asmgen.out("$name\t.byte  0,0,0,0,0  ; float")
                 } else {
-                    val floatFill = compTarget.machine.getFloat(staticValue).makeFloatFillAsm()
-                    asmgen.out("$name\t.byte  $floatFill  ; float $staticValue")
+                    val floatFill = compTarget.machine.getFloat(initialValue).makeFloatFillAsm()
+                    asmgen.out("$name\t.byte  $floatFill  ; float $initialValue")
                 }
             }
             DataType.STR -> {
                 throw AssemblyError("all string vars should have been interned into prog")
             }
-            in ArrayDatatypes -> arrayVariable2asm(name, variable.type, value as? ArrayLiteral, variable.arraysize)
+            in ArrayDatatypes -> arrayVariable2asm(name, variable.dt, variable.initialArrayValue, variable.length)
             else -> {
                 throw AssemblyError("weird dt")
             }
         }
     }
 
-    private fun arrayVariable2asm(varname: String, dt: DataType, value: ArrayLiteral?, orNumberOfZeros: Int?) {
+    private fun arrayVariable2asm(varname: String, dt: DataType, value: StArray?, orNumberOfZeros: Int?) {
         when(dt) {
             DataType.ARRAY_UB -> {
                 val data = makeArrayFillDataUnsigned(dt, value, orNumberOfZeros)
@@ -465,11 +553,9 @@ internal class ProgramAndVarsGen(
                 }
             }
             DataType.ARRAY_F -> {
-                val array = value?.value ?:
-                                Array(orNumberOfZeros!!) { defaultZero(ArrayToElementTypes.getValue(dt), Position.DUMMY) }
+                val array = value ?: zeroFilledArray(orNumberOfZeros!!)
                 val floatFills = array.map {
-                    val number = (it as NumericLiteral).number
-                    compTarget.machine.getFloat(number).makeFloatFillAsm()
+                    compTarget.machine.getFloat(it.number!!).makeFloatFillAsm()
                 }
                 asmgen.out(varname)
                 for (f in array.zip(floatFills))
@@ -479,30 +565,23 @@ internal class ProgramAndVarsGen(
         }
     }
 
-    private fun memdefsAndConsts2asm(block: Block) {
-        val mvs = variables.blockMemvars[block] ?: emptySet()
-        val consts = variables.blockConsts[block] ?: emptySet()
-        memdefsAndConsts2asm(mvs, consts)
+    private fun zeroFilledArray(numElts: Int): StArray {
+        val values = mutableListOf<StArrayElement>()
+        repeat(numElts) {
+            values.add(StArrayElement(0.0, null))
+        }
+        return values
     }
 
-    private fun memdefsAndConsts2asm(sub: Subroutine) {
-        val mvs = variables.subroutineMemvars[sub] ?: emptySet()
-        val consts = variables.subroutineConsts[sub] ?: emptySet()
-        memdefsAndConsts2asm(mvs, consts)
-    }
-
-    private fun memdefsAndConsts2asm(
-        memvars: Set<IVariablesAndConsts.MemoryMappedVariable>,
-        consts: Set<IVariablesAndConsts.ConstantNumberSymbol>
-    ) {
+    private fun memdefsAndConsts2asm(memvars: Collection<StMemVar>, consts: Collection<StConstant>) {
         memvars.forEach {
-            asmgen.out("  ${it.scopedname.last()} = ${it.address.toHex()}")
+            asmgen.out("  ${it.name} = ${it.address.toHex()}")
         }
         consts.forEach {
-            if(it.type==DataType.FLOAT)
-                asmgen.out("  ${it.scopedname.last()} = ${it.value}")
+            if(it.dt==DataType.FLOAT)
+                asmgen.out("  ${it.name} = ${it.value}")
             else
-                asmgen.out("  ${it.scopedname.last()} = ${it.value.toHex()}")
+                asmgen.out("  ${it.name} = ${it.value.toHex()}")
         }
     }
 
@@ -515,56 +594,49 @@ internal class ProgramAndVarsGen(
             }
     }
 
-    private fun outputStringvar(varname: String, dt: DataType, encoding: Encoding, value: String) {
-        asmgen.out("$varname\t; $dt $encoding:\"${escape(value).replace("\u0000", "<NULL>")}\"")
+    private fun outputStringvar(varname: String, encoding: Encoding, value: String) {
+        asmgen.out("$varname\t; $encoding:\"${value.escape().replace("\u0000", "<NULL>")}\"", false)
         val bytes = compTarget.encodeString(value, encoding).plus(0.toUByte())
         val outputBytes = bytes.map { "$" + it.toString(16).padStart(2, '0') }
         for (chunk in outputBytes.chunked(16))
             asmgen.out("  .byte  " + chunk.joinToString())
     }
 
-    private fun makeArrayFillDataUnsigned(dt: DataType, value: ArrayLiteral?, orNumberOfZeros: Int?): List<String> {
-        val array = value?.value ?:
-                        Array(orNumberOfZeros!!) { defaultZero(ArrayToElementTypes.getValue(dt), Position.DUMMY) }
+    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 as NumericLiteral).number.toInt()
+                    val number = it.number!!.toInt()
                     "$"+number.toString(16).padStart(2, '0')
                 }
             DataType.ARRAY_UW -> array.map {
-                when (it) {
-                    is NumericLiteral -> {
-                        "$" + it.number.toInt().toString(16).padStart(4, '0')
-                    }
-                    is AddressOf -> {
-                        asmgen.asmSymbolName(it.identifier)
-                    }
-                    is IdentifierReference -> {
-                        asmgen.asmSymbolName(it)
-                    }
-                    else -> throw AssemblyError("weird array elt dt")
+                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: ArrayLiteral?, orNumberOfZeros: Int?): List<String> {
-        val array = value?.value ?:
-                        Array(orNumberOfZeros!!) { defaultZero(ArrayToElementTypes.getValue(dt), Position.DUMMY) }
+    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 ->
-                // byte array can never contain pointer-to types, so treat values as all integers
                 array.map {
-                    val number = (it as NumericLiteral).number.toInt()
+                    val number = it.number!!.toInt()
                     "$"+number.toString(16).padStart(2, '0')
                 }
             DataType.ARRAY_B ->
-                // byte array can never contain pointer-to types, so treat values as all integers
                 array.map {
-                    val number = (it as NumericLiteral).number.toInt()
+                    val number = it.number!!.toInt()
                     val hexnum = number.absoluteValue.toString(16).padStart(2, '0')
                     if(number>=0)
                         "$$hexnum"
@@ -572,11 +644,11 @@ internal class ProgramAndVarsGen(
                         "-$$hexnum"
                 }
             DataType.ARRAY_UW -> array.map {
-                val number = (it as NumericLiteral).number.toInt()
+                val number = it.number!!.toInt()
                 "$" + number.toString(16).padStart(4, '0')
             }
             DataType.ARRAY_W -> array.map {
-                val number = (it as NumericLiteral).number.toInt()
+                val number = it.number!!.toInt()
                 val hexnum = number.absoluteValue.toString(16).padStart(4, '0')
                 if(number>=0)
                     "$$hexnum"

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

@@ -2,62 +2,71 @@ package prog8.codegen.cpu6502
 
 import com.github.michaelbull.result.fold
 import com.github.michaelbull.result.onSuccess
-import prog8.ast.base.ArrayDatatypes
-import prog8.ast.base.DataType
-import prog8.ast.base.IntegerDatatypes
-import prog8.ast.expressions.StringLiteral
-import prog8.ast.statements.Subroutine
-import prog8.ast.statements.ZeropageWish
-import prog8.compilerinterface.*
+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 vars: IVariablesAndConsts,
+internal class VariableAllocator(private val symboltable: SymbolTable,
                                  private val options: CompilationOptions,
-                                 private val errors: IErrorReporter) {
+                                 private val errors: IErrorReporter
+) {
 
     private val zeropage = options.compTarget.machine.zeropage
-    private val subroutineExtras = mutableMapOf<Subroutine, SubroutineExtraAsmInfo>()
     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!
      */
-    internal fun allocateZeropageVariables() {
+    private fun allocateZeropageVariables() {
         if(options.zeropage== ZeropageType.DONTUSE)
             return
 
-        val allVariables = (
-                        vars.blockVars.asSequence().flatMap { it.value } +
-                        vars.subroutineVars.asSequence().flatMap { it.value }
-                ).toList()
+        val allVariables = collectAllVariables(symboltable)
 
         val numberOfAllocatableVariables = allVariables.size
-        val varsRequiringZp = allVariables.filter { it.zp == ZeropageWish.REQUIRE_ZEROPAGE }
-        val varsPreferringZp = allVariables.filter { it.zp == ZeropageWish.PREFER_ZEROPAGE }
-        val varsDontCare = allVariables.filter { it.zp == ZeropageWish.DONTCARE }
-        val numberOfExplicitNonZpVariables = allVariables.count { it.zp == ZeropageWish.NOT_IN_ZEROPAGE }
+        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: Int = 0
-        var numberOfNonIntegerVariables: Int = 0
+        var numVariablesAllocatedInZP = 0
+        var numberOfNonIntegerVariables = 0
 
         varsRequiringZp.forEach { variable ->
-            val numElements = numArrayElements(variable)
             val result = zeropage.allocate(
-                variable.scopedname,
-                variable.type,
-                variable.scope,
-                numElements,
-                variable.initialValue,
+                variable.scopedName,
+                variable.dt,
+                variable.length,
                 variable.position,
                 errors
             )
@@ -73,13 +82,10 @@ internal class VariableAllocator(private val vars: IVariablesAndConsts,
 
         if(errors.noErrors()) {
             varsPreferringZp.forEach { variable ->
-                val numElements = numArrayElements(variable)
                 val result = zeropage.allocate(
-                    variable.scopedname,
-                    variable.type,
-                    variable.scope,
-                    numElements,
-                    variable.initialValue,
+                    variable.scopedName,
+                    variable.dt,
+                    variable.length,
                     variable.position,
                     errors
                 )
@@ -90,18 +96,15 @@ internal class VariableAllocator(private val vars: IVariablesAndConsts,
             // 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) {
-                    if(variable.type in IntegerDatatypes) {
+                for (variable in varsDontCare.sortedBy { it.scopedName.size }) {
+                    if(variable.dt in IntegerDatatypes) {
                         if(zeropage.free.isEmpty()) {
                             break
                         } else {
-                            val numElements = numArrayElements(variable)
                             val result = zeropage.allocate(
-                                variable.scopedname,
-                                variable.type,
-                                variable.scope,
-                                numElements,
-                                variable.initialValue,
+                                variable.scopedName,
+                                variable.dt,
+                                variable.length,
                                 variable.position,
                                 errors
                             )
@@ -113,54 +116,22 @@ internal class VariableAllocator(private val vars: IVariablesAndConsts,
             }
         }
 
-        println("  number of allocated vars: $numberOfAllocatableVariables")
-        println("  put into zeropage: $numVariablesAllocatedInZP,  non-zp allocatable: ${numberOfNonIntegerVariables+numberOfExplicitNonZpVariables}")
-        println("  zeropage free space: ${zeropage.free.size} bytes")
+//        println("  number of allocated vars: $numberOfAllocatableVariables")
+//        println("  put into zeropage: $numVariablesAllocatedInZP,  non-zp allocatable: ${numberOfNonIntegerVariables+numberOfExplicitNonZpVariables}")
+//        println("  zeropage free space: ${zeropage.free.size} bytes")
     }
 
-    internal fun isZpVar(scopedName: List<String>) = scopedName in zeropage.allocatedVariables
-
-    private fun numArrayElements(variable: IVariablesAndConsts.StaticVariable) =
-        when(variable.type) {
-            DataType.STR -> (variable.initialValue as StringLiteral).value.length
-            in ArrayDatatypes -> variable.arraysize!!
-            else -> null
+    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)
+            }
         }
-
-    internal fun subroutineExtra(sub: Subroutine): SubroutineExtraAsmInfo {
-        var extra = subroutineExtras[sub]
-        return if(extra==null) {
-            extra = SubroutineExtraAsmInfo()
-            subroutineExtras[sub] = extra
-            extra
-        }
-        else
-            extra
-    }
-
-    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
+        collect(st)
+        return vars
     }
 }
-
-/**
- * This class contains various attributes that influence the assembly code generator.
- * Conceptually it should be part of any INameScope.
- * But because the resulting code only creates "real" scopes on a subroutine level,
- * it's more consistent to only define these attributes on a Subroutine node.
- */
-internal class SubroutineExtraAsmInfo {
-    var usedRegsaveA = false
-    var usedRegsaveX = false
-    var usedRegsaveY = false
-    var usedFloatEvalResultVar1 = false
-    var usedFloatEvalResultVar2 = false
-
-    val extraVars = mutableListOf<Triple<DataType, String, UInt?>>()
-}

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

@@ -1,12 +1,13 @@
 package prog8.codegen.cpu6502.assignment
 
 import prog8.ast.Program
-import prog8.ast.base.*
 import prog8.ast.expressions.*
-import prog8.ast.statements.*
+import prog8.ast.statements.AssignTarget
+import prog8.ast.statements.Assignment
+import prog8.ast.statements.DirectMemoryWrite
+import prog8.ast.statements.Subroutine
+import prog8.code.core.*
 import prog8.codegen.cpu6502.AsmGen
-import prog8.compilerinterface.AssemblyError
-import prog8.compilerinterface.IMemSizer
 
 
 internal enum class TargetStorageKind {
@@ -39,7 +40,6 @@ internal class AsmAssignTarget(val kind: TargetStorageKind,
                                val origAstTarget: AssignTarget? = null
                                )
 {
-    val constMemoryAddress by lazy { memory?.addressExpression?.constValue(program)?.number?.toUInt() ?: 0u}
     val constArrayIndexValue by lazy { array?.indexer?.constIndex()?.toUInt() }
     val asmVarname: String by lazy {
         if (array == null)
@@ -124,9 +124,6 @@ internal class AsmAssignSource(val kind: SourceStorageKind,
                                val expression: Expression? = null
 )
 {
-    val constMemoryAddress by lazy { memory?.addressExpression?.constValue(program)?.number?.toUInt() ?: 0u}
-    val constArrayIndexValue by lazy { array?.indexer?.constIndex()?.toUInt() }
-
     val asmVarname: String
         get() = if(array==null)
             variableAsmName!!
@@ -134,8 +131,6 @@ internal class AsmAssignSource(val kind: SourceStorageKind,
             asmgen.asmVariableName(array.arrayvar)
 
     companion object {
-        fun fromAstSource(indexer: ArrayIndex, program: Program, asmgen: AsmGen): AsmAssignSource = fromAstSource(indexer.indexExpr, program, asmgen)
-
         fun fromAstSource(value: Expression, program: Program, asmgen: AsmGen): AsmAssignSource {
             val cv = value.constValue(program)
             if(cv!=null)
@@ -167,26 +162,20 @@ internal class AsmAssignSource(val kind: SourceStorageKind,
                     val dt = value.inferType(program).getOrElse { throw AssemblyError("unknown dt") }
                     AsmAssignSource(SourceStorageKind.ARRAY, program, asmgen, dt, array = value)
                 }
+                is BuiltinFunctionCall -> {
+                    val returnType = value.inferType(program)
+                    AsmAssignSource(SourceStorageKind.EXPRESSION, program, asmgen, returnType.getOrElse { throw AssemblyError("unknown dt") }, expression = value)
+                }
                 is FunctionCallExpression -> {
-                    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")
+                    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 BuiltinFunctionPlaceholder -> {
-                            val returnType = value.inferType(program)
-                            AsmAssignSource(SourceStorageKind.EXPRESSION, program, asmgen, returnType.getOrElse { throw AssemblyError("unknown dt") }, expression = value)
-                        }
-                        else -> {
-                            throw AssemblyError("weird call")
-                        }
-                    }
+                    AsmAssignSource(SourceStorageKind.EXPRESSION, program, asmgen, returnType, expression = value)
                 }
                 else -> {
-                    val dt = value.inferType(program)
-                    AsmAssignSource(SourceStorageKind.EXPRESSION, program, asmgen, dt.getOrElse { throw AssemblyError("unknown dt") }, 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/AugmentableAssignmentAsmGen.kt

@@ -1,14 +1,12 @@
 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.code.core.*
 import prog8.codegen.cpu6502.AsmGen
 import prog8.codegen.cpu6502.VariableAllocator
-import prog8.compilerinterface.AssemblyError
-import prog8.compilerinterface.CpuType
 
 
 internal class AugmentableAssignmentAsmGen(private val program: Program,
@@ -30,7 +28,6 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                     "+" -> {}
                     "-" -> inplaceNegate(target, type)
                     "~" -> inplaceInvert(target, type)
-                    "not" -> inplaceBooleanNot(target, type)
                     else -> throw AssemblyError("invalid prefix operator")
                 }
             }
@@ -393,9 +390,9 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                     bne  -
 +""")
             }
-            "&", "and" -> asmgen.out(" and  P8ZP_SCRATCH_B1")
-            "|", "or" -> asmgen.out(" ora  P8ZP_SCRATCH_B1")
-            "^", "xor" -> asmgen.out(" eor  P8ZP_SCRATCH_B1")
+            "&" -> asmgen.out(" and  P8ZP_SCRATCH_B1")
+            "|" -> asmgen.out(" ora  P8ZP_SCRATCH_B1")
+            "^" -> asmgen.out(" eor  P8ZP_SCRATCH_B1")
             else -> throw AssemblyError("invalid operator for in-place modification $operator")
         }
         asmgen.storeAIntoZpPointerVar(sourceName)
@@ -430,9 +427,9 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                         bne  -
 +""")
             }
-            "&", "and" -> asmgen.out(" and  $otherName")
-            "|", "or" -> asmgen.out(" ora  $otherName")
-            "^", "xor" -> asmgen.out(" eor  $otherName")
+            "&" -> asmgen.out(" and  $otherName")
+            "|" -> asmgen.out(" ora  $otherName")
+            "^" -> asmgen.out(" eor  $otherName")
             else -> throw AssemblyError("invalid operator for in-place modification $operator")
         }
         asmgen.storeAIntoZpPointerVar(sourceName)
@@ -487,17 +484,17 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                     asmgen.storeAIntoZpPointerVar(sourceName)
                 }
             }
-            "&", "and" -> {
+            "&" -> {
                 val sourceName = asmgen.loadByteFromPointerIntoA(pointervar)
                 asmgen.out("  and  #$value")
                 asmgen.storeAIntoZpPointerVar(sourceName)
             }
-            "|", "or" -> {
+            "|"-> {
                 val sourceName = asmgen.loadByteFromPointerIntoA(pointervar)
                 asmgen.out("  ora  #$value")
                 asmgen.storeAIntoZpPointerVar(sourceName)
             }
-            "^", "xor" -> {
+            "^" -> {
                 val sourceName = asmgen.loadByteFromPointerIntoA(pointervar)
                 asmgen.out("  eor  #$value")
                 asmgen.storeAIntoZpPointerVar(sourceName)
@@ -565,15 +562,15 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
 +""")
                 }
             }
-            "&", "and" -> {
+            "&" -> {
                 asmgen.assignExpressionToRegister(value, RegisterOrPair.A)
                 asmgen.out("  and  $name |  sta  $name")
             }
-            "|", "or" -> {
+            "|" -> {
                 asmgen.assignExpressionToRegister(value, RegisterOrPair.A)
                 asmgen.out("  ora  $name |  sta  $name")
             }
-            "^", "xor" -> {
+            "^" -> {
                 asmgen.assignExpressionToRegister(value, RegisterOrPair.A)
                 asmgen.out("  eor  $name |  sta  $name")
             }
@@ -651,9 +648,9 @@ 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  $name |  and  $otherName |  sta  $name")
+            "|" -> asmgen.out(" lda  $name |  ora  $otherName |  sta  $name")
+            "^" -> asmgen.out(" lda  $name |  eor  $otherName |  sta  $name")
             "==" -> {
                 asmgen.out("""
                     lda  $otherName
@@ -742,9 +739,9 @@ 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  $name |  and  #$value |  sta  $name")
+            "|" -> asmgen.out(" lda  $name |  ora  #$value |  sta  $name")
+            "^" -> asmgen.out(" lda  $name |  eor  #$value |  sta  $name")
             "==" -> {
                 asmgen.out("""
                     lda  $name
@@ -787,15 +784,15 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                     sbc  P8ZP_SCRATCH_B1
                     sta  $name""")
             }
-            "|", "or" -> {
+            "|" -> {
                 asmgen.translateDirectMemReadExpressionToRegAorStack(memread, false)
                 asmgen.out("  ora  $name  |  sta  $name")
             }
-            "&", "and" -> {
+            "&" -> {
                 asmgen.translateDirectMemReadExpressionToRegAorStack(memread, false)
                 asmgen.out("  and  $name  |  sta  $name")
             }
-            "^", "xor" -> {
+            "^" -> {
                 asmgen.translateDirectMemReadExpressionToRegAorStack(memread, false)
                 asmgen.out("  eor  $name  |  sta  $name")
             }
@@ -830,11 +827,11 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                     dec  $name+1
 +""")
             }
-            "|", "or" -> {
+            "|" -> {
                 asmgen.translateDirectMemReadExpressionToRegAorStack(memread, false)
                 asmgen.out("  ora  $name  |  sta  $name")
             }
-            "&", "and" -> {
+            "&" -> {
                 asmgen.translateDirectMemReadExpressionToRegAorStack(memread, false)
                 asmgen.out("  and  $name  |  sta  $name")
                 if(dt in WordDatatypes) {
@@ -844,7 +841,7 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                         asmgen.out("  lda  #0 |  sta  $name+1")
                 }
             }
-            "^", "xor" -> {
+            "^" -> {
                 asmgen.translateDirectMemReadExpressionToRegAorStack(memread, false)
                 asmgen.out("  eor  $name  |  sta  $name")
             }
@@ -1061,7 +1058,7 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                     }
                 }
             }
-            "&", "and" -> {
+            "&" -> {
                 when {
                     value == 0 -> {
                         if(asmgen.isTargetCpu(CpuType.CPU65c02))
@@ -1098,7 +1095,7 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                     else -> asmgen.out("  lda  $name |  and  #<$value |  sta  $name |  lda  $name+1 |  and  #>$value |  sta  $name+1")
                 }
             }
-            "|", "or" -> {
+            "|" -> {
                 when {
                     value == 0 -> {}
                     value and 255 == 0 -> asmgen.out("  lda  $name+1 |  ora  #>$value |  sta  $name+1")
@@ -1106,7 +1103,7 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                     else -> asmgen.out("  lda  $name |  ora  #<$value |  sta  $name |  lda  $name+1 |  ora  #>$value |  sta  $name+1")
                 }
             }
-            "^", "xor" -> {
+            "^" -> {
                 when {
                     value == 0 -> {}
                     value and 255 == 0 -> asmgen.out("  lda  $name+1 |  eor  #>$value |  sta  $name+1")
@@ -1270,7 +1267,7 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
 +""")
                         }
                     }
-                    "&", "and" -> {
+                    "&" -> {
                         asmgen.out("  lda  $otherName |  and  $name |  sta  $name")
                         if(dt in WordDatatypes) {
                             if(asmgen.isTargetCpu(CpuType.CPU65c02))
@@ -1279,8 +1276,8 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                                 asmgen.out("  lda  #0 |  sta  $name+1")
                         }
                     }
-                    "|", "or" -> asmgen.out("  lda  $otherName |  ora  $name |  sta  $name")
-                    "^", "xor" -> asmgen.out("  lda  $otherName |  eor  $name |  sta  $name")
+                    "|" -> asmgen.out("  lda  $otherName |  ora  $name |  sta  $name")
+                    "^" -> asmgen.out("  lda  $otherName |  eor  $name |  sta  $name")
                     else -> throw AssemblyError("invalid operator for in-place modification $operator")
                 }
             }
@@ -1351,9 +1348,9 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                         """)
                     }
                     "<<", ">>" -> throw AssemblyError("shift by a word value not supported, max is a byte")
-                    "&", "and" -> asmgen.out(" lda  $name |  and  $otherName |  sta  $name |  lda  $name+1 |  and  $otherName+1 |  sta  $name+1")
-                    "|", "or" -> asmgen.out(" lda  $name |  ora  $otherName |  sta  $name |  lda  $name+1 |  ora  $otherName+1 |  sta  $name+1")
-                    "^", "xor" -> asmgen.out(" lda  $name |  eor  $otherName |  sta  $name |  lda  $name+1 |  eor  $otherName+1 |  sta  $name+1")
+                    "&" -> asmgen.out(" lda  $name |  and  $otherName |  sta  $name |  lda  $name+1 |  and  $otherName+1 |  sta  $name+1")
+                    "|" -> asmgen.out(" lda  $name |  ora  $otherName |  sta  $name |  lda  $name+1 |  ora  $otherName+1 |  sta  $name+1")
+                    "^" -> asmgen.out(" lda  $name |  eor  $otherName |  sta  $name |  lda  $name+1 |  eor  $otherName+1 |  sta  $name+1")
                     else -> throw AssemblyError("invalid operator for in-place modification $operator")
                 }
             }
@@ -1523,7 +1520,7 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                             bne  -
 +""")
                     }
-                    "&", "and" -> {
+                    "&" -> {
                         asmgen.assignExpressionToRegister(value, RegisterOrPair.A)
                         asmgen.out("  and  $name |  sta  $name")
                         if(dt in WordDatatypes) {
@@ -1533,11 +1530,11 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                                 asmgen.out("  lda  #0 |  sta  $name+1")
                         }
                     }
-                    "|", "or" -> {
+                    "|" -> {
                         asmgen.assignExpressionToRegister(value, RegisterOrPair.A)
                         asmgen.out("  ora  $name |  sta  $name")
                     }
-                    "^", "xor" -> {
+                    "^" -> {
                         asmgen.assignExpressionToRegister(value, RegisterOrPair.A)
                         asmgen.out("  eor  $name |  sta  $name")
                     }
@@ -1569,15 +1566,15 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                         remainderVarByWordInAY()
                     }
                     "<<", ">>" -> throw AssemblyError("shift by a word value not supported, max is a byte")
-                    "&", "and" -> {
+                    "&" -> {
                         asmgen.assignExpressionToRegister(value, RegisterOrPair.AY)
                         asmgen.out("  and  $name |  sta  $name |  tya |  and  $name+1 |  sta  $name+1")
                     }
-                    "|", "or" -> {
+                    "|" -> {
                         asmgen.assignExpressionToRegister(value, RegisterOrPair.AY)
                         asmgen.out("  ora  $name |  sta  $name |  tya |  ora  $name+1 |  sta  $name+1")
                     }
-                    "^", "xor" -> {
+                    "^" -> {
                         asmgen.assignExpressionToRegister(value, RegisterOrPair.AY)
                         asmgen.out("  eor  $name |  sta  $name |  tya |  eor  $name+1 |  sta  $name+1")
                     }
@@ -1592,14 +1589,6 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
         asmgen.assignExpressionToRegister(value, RegisterOrPair.FAC1)
         asmgen.saveRegisterLocal(CpuRegister.X, scope)
         when (operator) {
-            "**" -> {
-                asmgen.out("""
-                    lda  #<$name
-                    ldy  #>$name
-                    jsr  floats.CONUPK
-                    jsr  floats.FPWRT
-                """)
-            }
             "+" -> {
                 asmgen.out("""
                     lda  #<$name
@@ -1646,28 +1635,6 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
         val otherName = asmgen.asmVariableName(ident)
         asmgen.saveRegisterLocal(CpuRegister.X, scope)
         when (operator) {
-            "**" -> {
-                if(asmgen.haveFPWRcall()) {
-                    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  #<$name
@@ -1723,28 +1690,6 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
         val constValueName = allocator.getFloatAsmConst(value)
         asmgen.saveRegisterLocal(CpuRegister.X, scope)
         when (operator) {
-            "**" -> {
-                if(asmgen.haveFPWRcall()) {
-                    asmgen.out("""
-                        lda  #<$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
@@ -1854,136 +1799,6 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
         }
     }
 
-    internal fun inplaceBooleanNot(target: AsmAssignTarget, dt: DataType) {
-        when (dt) {
-            DataType.UBYTE -> {
-                when (target.kind) {
-                    TargetStorageKind.VARIABLE -> {
-                        asmgen.out("""
-                            lda  ${target.asmVarname}
-                            beq  +
-                            lda  #1
-+                           eor  #1
-                            sta  ${target.asmVarname}""")
-                    }
-                    TargetStorageKind.MEMORY -> {
-                        val mem = target.memory!!
-                        when (mem.addressExpression) {
-                            is NumericLiteral -> {
-                                val addr = (mem.addressExpression as NumericLiteral).number.toHex()
-                                asmgen.out("""
-                                    lda  $addr
-                                    beq  +
-                                    lda  #1
-+                                   eor  #1
-                                    sta  $addr""")
-                            }
-                            is IdentifierReference -> {
-                                val sourceName = asmgen.loadByteFromPointerIntoA(mem.addressExpression as IdentifierReference)
-                                asmgen.out("""
-                                    beq  +
-                                    lda  #1
-+                                   eor  #1""")
-                                asmgen.storeAIntoZpPointerVar(sourceName)
-                            }
-                            else -> {
-                                asmgen.assignExpressionToVariable(mem.addressExpression, "P8ZP_SCRATCH_W2", DataType.UWORD, target.scope)
-                                asmgen.loadAFromZpPointerVar("P8ZP_SCRATCH_W2")
-                                asmgen.out("""
-                                    beq  +
-                                    lda  #1
-+                                   eor  #1""")
-                                asmgen.storeAIntoZpPointerVar("P8ZP_SCRATCH_W2")
-                            }
-                        }
-                    }
-                    TargetStorageKind.REGISTER -> {
-                        when(target.register!!) {
-                            RegisterOrPair.A -> asmgen.out("""
-                                cmp  #0
-                                beq  +
-                                lda  #1
-+                               eor  #1""")
-                            RegisterOrPair.X -> asmgen.out("""
-                                txa
-                                beq  +
-                                lda  #1
-+                               eor  #1
-                                tax""")
-                            RegisterOrPair.Y -> asmgen.out("""
-                                tya
-                                beq  +
-                                lda  #1
-+                               eor  #1
-                                tay""")
-                            else -> throw AssemblyError("invalid reg dt for byte not")
-                        }
-                    }
-                    TargetStorageKind.STACK -> TODO("no asm gen for byte stack not")
-                    else -> throw AssemblyError("no asm gen for in-place not of ubyte ${target.kind}")
-                }
-            }
-            DataType.UWORD -> {
-                when (target.kind) {
-                    TargetStorageKind.VARIABLE -> {
-                        asmgen.out("""
-                            lda  ${target.asmVarname}
-                            ora  ${target.asmVarname}+1
-                            beq  +
-                            lda  #1
-+                           eor  #1
-                            sta  ${target.asmVarname}
-                            lsr  a
-                            sta  ${target.asmVarname}+1""")
-                    }
-                    TargetStorageKind.REGISTER -> {
-                        when(target.register!!) {
-                            RegisterOrPair.AX -> {
-                                asmgen.out("""
-                                    stx  P8ZP_SCRATCH_REG
-                                    ora  P8ZP_SCRATCH_REG
-                                    beq  +
-                                    lda  #0
-                                    tax
-                                    beq  ++
-        +                           lda  #1
-        +""")
-                            }
-                            RegisterOrPair.AY -> {
-                                asmgen.out("""
-                                    sty  P8ZP_SCRATCH_REG
-                                    ora  P8ZP_SCRATCH_REG
-                                    beq  +
-                                    lda  #0
-                                    tay
-                                    beq  ++
-        +                           lda  #1
-        +""")
-                            }
-                            RegisterOrPair.XY -> {
-                                asmgen.out("""
-                                    stx  P8ZP_SCRATCH_REG
-                                    tya
-                                    ora  P8ZP_SCRATCH_REG
-                                    beq  +
-                                    ldy  #0
-                                    ldx  #0
-                                    beq  ++
-        +                           ldx  #1
-        +""")
-                            }
-                            in Cx16VirtualRegisters -> throw AssemblyError("cx16 virtual regs should be variables, not real registers")
-                            else -> throw AssemblyError("invalid reg dt for word not")
-                        }
-                    }
-                    TargetStorageKind.STACK -> TODO("no asm gen for word stack not")
-                    else -> throw AssemblyError("no asm gen for in-place not of uword for ${target.kind}")
-                }
-            }
-            else -> throw AssemblyError("boolean-not of invalid type")
-        }
-    }
-
     internal fun inplaceInvert(target: AsmAssignTarget, dt: DataType) {
         when (dt) {
             DataType.UBYTE -> {

codeGenExperimental/build.gradle

@@ -24,10 +24,12 @@ compileTestKotlin {
 }
 
 dependencies {
-    implementation project(':compilerAst')
+    implementation project(':codeAst')
+    implementation project(':codeCore')
     implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8"
-    implementation "com.michael-bull.kotlin-result:kotlin-result-jvm:1.1.12"
     // implementation "org.jetbrains.kotlin:kotlin-reflect"
+    implementation "com.michael-bull.kotlin-result:kotlin-result-jvm:1.1.16"
+
 }
 
 sourceSets {

codeGenExperimental/codeGenExperimental.iml

@@ -9,8 +9,8 @@
     <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="compilerInterfaces" />
     <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

@@ -1,13 +1,13 @@
-package prog8.codegen.experimental6502
+package prog8.codegen.experimental
 
-import prog8.compilerinterface.CompilationOptions
-import prog8.compilerinterface.IAssemblyProgram
+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 false
+        return true
     }
 }

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

@@ -0,0 +1,668 @@
+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.evalStackBaseAddress!=null)
+            xml.attr("evalstackbase", options.evalStackBaseAddress!!.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()
+            }
+        }
+        if(options.symbolDefs.isNotEmpty()) {
+            xml.startChildren()
+            options.symbolDefs.forEach { name, value ->
+                xml.elt("symboldef")
+                xml.attr("name", name)
+                xml.attr("value", value)
+                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 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(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")
+    }
+}

codeGenExperimental6502/src/prog8/codegen/experimental6502/AsmGen.kt

@@ -1,18 +0,0 @@
-package prog8.codegen.experimental6502
-
-import prog8.ast.Program
-import prog8.compilerinterface.*
-
-class AsmGen(internal val program: Program,
-             internal val errors: IErrorReporter,
-             internal val variables: IVariablesAndConsts,
-             internal val options: CompilationOptions): IAssemblyGenerator {
-
-    override fun compileToAssembly(): IAssemblyProgram? {
-
-        println("\n** experimental 65(c)02 code generator **\n")
-
-        println("..todo: create assembly code into ${options.outputDir.toAbsolutePath()}..")
-        return AssemblyProgram("dummy")
-    }
-}

codeGenTargets/readme-tests.txt

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

codeGenTargets/src/prog8/codegen/target/C128Target.kt

@@ -1,27 +0,0 @@
-package prog8.codegen.target
-
-import prog8.ast.expressions.Expression
-import prog8.ast.statements.RegisterOrStatusflag
-import prog8.ast.statements.Subroutine
-import prog8.codegen.target.c128.C128MachineDefinition
-import prog8.codegen.target.cbm.CbmMemorySizer
-import prog8.codegen.target.cbm.asmsub6502ArgsEvalOrder
-import prog8.codegen.target.cbm.asmsub6502ArgsHaveRegisterClobberRisk
-import prog8.compilerinterface.ICompilationTarget
-import prog8.compilerinterface.IMemSizer
-import prog8.compilerinterface.IStringEncoding
-
-
-class C128Target: ICompilationTarget, IStringEncoding by Encoder, IMemSizer by CbmMemorySizer {
-    override val name = NAME
-    override val machine = C128MachineDefinition()
-
-    companion object {
-        const val NAME = "c128"
-    }
-
-    override fun asmsubArgsEvalOrder(sub: Subroutine): List<Int> =
-        asmsub6502ArgsEvalOrder(sub)
-    override fun asmsubArgsHaveRegisterClobberRisk(args: List<Expression>, paramRegisters: List<RegisterOrStatusflag>) =
-        asmsub6502ArgsHaveRegisterClobberRisk(args, paramRegisters)
-}

codeGenTargets/src/prog8/codegen/target/C64Target.kt

@@ -1,27 +0,0 @@
-package prog8.codegen.target
-
-import prog8.ast.expressions.Expression
-import prog8.ast.statements.RegisterOrStatusflag
-import prog8.ast.statements.Subroutine
-import prog8.codegen.target.c64.C64MachineDefinition
-import prog8.codegen.target.cbm.CbmMemorySizer
-import prog8.codegen.target.cbm.asmsub6502ArgsEvalOrder
-import prog8.codegen.target.cbm.asmsub6502ArgsHaveRegisterClobberRisk
-import prog8.compilerinterface.ICompilationTarget
-import prog8.compilerinterface.IMemSizer
-import prog8.compilerinterface.IStringEncoding
-
-
-class C64Target: ICompilationTarget, IStringEncoding by Encoder, IMemSizer by CbmMemorySizer {
-    override val name = NAME
-    override val machine = C64MachineDefinition()
-
-    companion object {
-        const val NAME = "c64"
-    }
-
-    override fun asmsubArgsEvalOrder(sub: Subroutine): List<Int> =
-        asmsub6502ArgsEvalOrder(sub)
-    override fun asmsubArgsHaveRegisterClobberRisk(args: List<Expression>, paramRegisters: List<RegisterOrStatusflag>) =
-        asmsub6502ArgsHaveRegisterClobberRisk(args, paramRegisters)
-}

codeGenTargets/src/prog8/codegen/target/Cx16Target.kt

@@ -1,27 +0,0 @@
-package prog8.codegen.target
-
-import prog8.ast.expressions.Expression
-import prog8.ast.statements.RegisterOrStatusflag
-import prog8.ast.statements.Subroutine
-import prog8.codegen.target.cbm.CbmMemorySizer
-import prog8.codegen.target.cbm.asmsub6502ArgsEvalOrder
-import prog8.codegen.target.cbm.asmsub6502ArgsHaveRegisterClobberRisk
-import prog8.codegen.target.cx16.CX16MachineDefinition
-import prog8.compilerinterface.ICompilationTarget
-import prog8.compilerinterface.IMemSizer
-import prog8.compilerinterface.IStringEncoding
-
-
-class Cx16Target: ICompilationTarget, IStringEncoding by Encoder, IMemSizer by CbmMemorySizer {
-    override val name = NAME
-    override val machine = CX16MachineDefinition()
-
-    companion object {
-        const val NAME = "cx16"
-    }
-
-    override fun asmsubArgsEvalOrder(sub: Subroutine): List<Int> =
-        asmsub6502ArgsEvalOrder(sub)
-    override fun asmsubArgsHaveRegisterClobberRisk(args: List<Expression>, paramRegisters: List<RegisterOrStatusflag>) =
-        asmsub6502ArgsHaveRegisterClobberRisk(args, paramRegisters)
-}

codeGenTargets/src/prog8/codegen/target/cbm/CbmMemorySizer.kt

@@ -1,31 +0,0 @@
-package prog8.codegen.target.cbm
-
-import prog8.ast.base.*
-import prog8.ast.expressions.StringLiteral
-import prog8.ast.statements.VarDecl
-import prog8.compilerinterface.IMemSizer
-
-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(decl: VarDecl): Int {
-        return when(decl.type) {
-            VarDeclType.CONST -> 0
-            VarDeclType.VAR, VarDeclType.MEMORY -> {
-                when(val dt = decl.datatype) {
-                    in NumericDatatypes -> return memorySize(dt)
-                    in ArrayDatatypes -> decl.arraysize!!.constIndex()!! * memorySize(ArrayToElementTypes.getValue(dt))
-                    DataType.STR -> (decl.value as StringLiteral).value.length + 1
-                    else -> 0
-                }
-            }
-        }
-    }
-}

codeGenVirtual/build.gradle

@@ -0,0 +1,65 @@
+
+plugins {
+    id 'java'
+    id 'application'
+    id "org.jetbrains.kotlin.jvm"
+    id "io.kotest" version "0.3.9"
+}
+
+java {
+    toolchain {
+        languageVersion = JavaLanguageVersion.of(javaVersion)
+    }
+}
+
+compileKotlin {
+    kotlinOptions {
+        jvmTarget = javaVersion
+    }
+}
+
+compileTestKotlin {
+    kotlinOptions {
+        jvmTarget = javaVersion
+    }
+}
+
+dependencies {
+    implementation project(':codeAst')
+    implementation project(':codeCore')
+    implementation project(':virtualmachine')
+    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8"
+    // implementation "org.jetbrains.kotlin:kotlin-reflect"
+    implementation "com.michael-bull.kotlin-result:kotlin-result-jvm:1.1.16"
+
+    testImplementation 'io.kotest:kotest-runner-junit5-jvm:5.3.2'
+}
+
+sourceSets {
+    main {
+        java {
+            srcDirs = ["${project.projectDir}/src"]
+        }
+        resources {
+            srcDirs = ["${project.projectDir}/res"]
+        }
+    }
+    test {
+        java {
+            srcDir "${project.projectDir}/test"
+        }
+    }
+}
+
+test {
+    // Enable JUnit 5 (Gradle 4.6+).
+    useJUnitPlatform()
+
+    // Always run tests, even when nothing changed.
+    dependsOn 'cleanTest'
+
+    // Show test results.
+    testLogging {
+        events "skipped", "failed"
+    }
+}

codeGenVirtual/codeGenVirtual.iml

@@ -0,0 +1,19 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<module type="JAVA_MODULE" version="4">
+  <component name="NewModuleRootManager" inherit-compiler-output="true">
+    <exclude-output />
+    <content url="file://$MODULE_DIR$">
+      <sourceFolder url="file://$MODULE_DIR$/src" isTestSource="false" />
+      <sourceFolder url="file://$MODULE_DIR$/test" isTestSource="true" />
+    </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="library" name="io.kotest.assertions.core.jvm" level="project" />
+    <orderEntry type="library" name="io.kotest.runner.junit5.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
+
+
+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)
+    fun getBlocks(): List<VmCodeChunk> = blocks
+}
+
+sealed class VmCodeLine
+
+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 -> {}
+            }
+        }
+    }
+}
+
+class VmCodeLabel(val name: List<String>): VmCodeLine()
+internal class VmCodeComment(val comment: String): VmCodeLine()
+
+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 +1,242 @@
+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)
+            }
+            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)
+
+            if(array.variable.type==DataType.UWORD) {
+                // indexing a pointer var instead of a real array or string
+                if(itemsize!=1)
+                    throw AssemblyError("non-array var indexing requires bytes dt")
+                if(array.index.type!=DataType.UBYTE)
+                    throw AssemblyError("non-array var indexing requires bytes index")
+                val idxReg = codeGen.vmRegisters.nextFree()
+                code += expressionEval.translateExpression(array.index, idxReg, -1)
+                code += VmCodeInstruction(Opcode.STOREIX, vmDt, reg1=resultRegister, reg2=idxReg, value = variableAddr)
+                return code
+            }
+
+            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 +1,376 @@
+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)
+            "rol" -> funcRolRor(Opcode.ROXL, call, resultRegister)
+            "ror" -> funcRolRor(Opcode.ROXR, call, resultRegister)
+            "rol2" -> funcRolRor(Opcode.ROL, call, resultRegister)
+            "ror2" -> funcRolRor(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 notNegativeLabel = codeGen.createLabelName()
+                    val compareReg = codeGen.vmRegisters.nextFree()
+                    code += VmCodeInstruction(Opcode.LOADR, VmDataType.BYTE, reg1=compareReg, reg2=resultRegister)
+                    code += VmCodeInstruction(Opcode.AND, VmDataType.BYTE, reg1=compareReg, value=0x80)
+                    code += VmCodeInstruction(Opcode.BZ, VmDataType.BYTE, reg1=compareReg, labelSymbol = notNegativeLabel)
+                    code += VmCodeInstruction(Opcode.NEG, VmDataType.BYTE, reg1=resultRegister)
+                    code += VmCodeInstruction(Opcode.EXT, VmDataType.BYTE, reg1=resultRegister)
+                    code += VmCodeLabel(notNegativeLabel)
+                }
+                DataType.WORD -> {
+                    val notNegativeLabel = codeGen.createLabelName()
+                    val compareReg = codeGen.vmRegisters.nextFree()
+                    code += VmCodeInstruction(Opcode.LOADR, VmDataType.WORD, reg1=compareReg, reg2=resultRegister)
+                    code += VmCodeInstruction(Opcode.AND, VmDataType.WORD, reg1=compareReg, value=0x8000)
+                    code += VmCodeInstruction(Opcode.BZ, VmDataType.WORD, reg1=compareReg, 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 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 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 funcRolRor(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 +1,830 @@
+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)
+    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)
+            }
+        }
+
+        if(options.symbolDefs.isNotEmpty())
+            throw AssemblyError("virtual target doesn't support symbols defined on the commandline")
+        if(options.evalStackBaseAddress!=null)
+            throw AssemblyError("virtual target doesn't use eval-stack")
+
+        for (block in program.allBlocks()) {
+            vmprog.addBlock(translate(block))
+        }
+
+        if(options.optimize) {
+            val optimizer = VmPeepholeOptimizer(vmprog, allocations)
+            optimizer.optimize()
+        }
+
+        println("Vm codegen: virtual registers=${vmRegisters.peekNext()} memory usage=${allocations.freeMem}")
+
+        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 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 {
+            // TODO WHY THID DISTINCTION?
+            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 {
+            // TODO WHY THIS DISTICTION ?
+            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 -> {
+                code += if(value>0) {
+                    VmCodeInstruction(Opcode.ADD, dt, reg1 = reg, value=value)
+                } else {
+                    VmCodeInstruction(Opcode.SUB, dt, reg1 = reg, value=-value)
+                }
+            }
+        }
+        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.ADDR, dt, reg1 = valueReg, reg2 = operandReg)          // TODO USE ADDM?
+                    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.SUBR, dt, reg1 = valueReg, reg2 = operandReg)          // TODO USE ADDM?
+                    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
+        code += if(factor==0f) {
+            VmCodeInstruction(Opcode.LOAD, VmDataType.FLOAT, fpReg1 = fpReg, fpValue = 0f)
+        } else {
+            VmCodeInstruction(Opcode.MUL, VmDataType.FLOAT, fpReg1 = fpReg, fpValue=factor)
+        }
+        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 {
+            code += if (factor == 0) {
+                VmCodeInstruction(Opcode.LOAD, dt, reg1=reg, value=0)
+            } else {
+                VmCodeInstruction(Opcode.MUL, dt, reg1=reg, value=factor)
+            }
+        }
+        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
+        code += if(factor==0f) {
+            VmCodeInstruction(Opcode.LOAD, VmDataType.FLOAT, fpReg1 = fpReg, fpValue = Float.MAX_VALUE)
+        } else {
+            VmCodeInstruction(Opcode.DIVS, VmDataType.FLOAT, fpReg1 = fpReg, fpValue=factor)
+        }
+        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 {
+            code += if (factor == 0) {
+                VmCodeInstruction(Opcode.LOAD, dt, reg1=reg, value=0xffff)
+            } else {
+                if(signed)
+                    VmCodeInstruction(Opcode.DIVS, dt, reg1=reg, value=factor)
+                else
+                    VmCodeInstruction(Opcode.DIV, dt, reg1=reg, value=factor)
+            }
+        }
+        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.BOOL,
+            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 +1,856 @@
+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 PtRange,
+            is PtArray,
+            is PtString -> throw AssemblyError("range/arrayliteral/string should no longer occur as expression")
+            else -> throw AssemblyError("weird expression")
+        }
+        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.variable.type==DataType.UWORD) {
+            // indexing a pointer var instead of a real array or string
+            if(eltSize!=1)
+                throw AssemblyError("non-array var indexing requires bytes dt")
+            if(arrayIx.index.type!=DataType.UBYTE)
+                throw AssemblyError("non-array var indexing requires bytes index")
+            code += translateExpression(arrayIx.index, idxReg, -1)
+            code += VmCodeInstruction(Opcode.LOADIX, vmDt, reg1=resultRegister, reg2=idxReg, value = arrayLocation)
+            return code
+        }
+
+        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 mask = if(vmDt==VmDataType.BYTE) 0x00ff else 0xffff
+                code += VmCodeInstruction(Opcode.XOR, vmDt, reg1=resultRegister, value=mask)
+            }
+            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 -> {
+                code += when(cast.value.type) {
+                    DataType.UBYTE -> {
+                        VmCodeInstruction(Opcode.FFROMUB, VmDataType.FLOAT, reg1=actualResultReg, fpReg1 = actualResultFpReg)
+                    }
+                    DataType.BYTE -> {
+                        VmCodeInstruction(Opcode.FFROMSB, VmDataType.FLOAT, reg1=actualResultReg, fpReg1 = actualResultFpReg)
+                    }
+                    DataType.UWORD -> {
+                        VmCodeInstruction(Opcode.FFROMUW, VmDataType.FLOAT, reg1=actualResultReg, fpReg1 = actualResultFpReg)
+                    }
+                    DataType.WORD -> {
+                        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)
+            "|" -> operatorOr(binExpr, vmDt, resultRegister)
+            "&" -> operatorAnd(binExpr, vmDt, resultRegister)
+            "^" -> 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)
+                    code += VmCodeInstruction(Opcode.INV, vmDt, reg1=resultRegister)
+                code += VmCodeInstruction(Opcode.AND, vmDt, reg1=resultRegister, value=1)
+            } 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()
+        if(binExpr.right is PtNumber) {
+            code += translateExpression(binExpr.left, resultRegister, -1)
+            code += VmCodeInstruction(Opcode.XOR, vmDt, reg1 = resultRegister, value=(binExpr.right as PtNumber).number.toInt())
+        } else {
+            val rightResultReg = codeGen.vmRegisters.nextFree()
+            code += translateExpression(binExpr.left, resultRegister, -1)
+            code += translateExpression(binExpr.right, rightResultReg, -1)
+            code += VmCodeInstruction(Opcode.XORR, 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()
+        if(binExpr.right is PtNumber) {
+            code += translateExpression(binExpr.left, resultRegister, -1)
+            code += VmCodeInstruction(Opcode.AND, vmDt, reg1 = resultRegister, value=(binExpr.right as PtNumber).number.toInt())
+        } else {
+            val rightResultReg = codeGen.vmRegisters.nextFree()
+            code += translateExpression(binExpr.left, resultRegister, -1)
+            code += translateExpression(binExpr.right, rightResultReg, -1)
+            code += VmCodeInstruction(Opcode.ANDR, 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()
+        if(binExpr.right is PtNumber) {
+            code += translateExpression(binExpr.left, resultRegister, -1)
+            code += VmCodeInstruction(Opcode.OR, vmDt, reg1 = resultRegister, value=(binExpr.right as PtNumber).number.toInt())
+        } else {
+            val rightResultReg = codeGen.vmRegisters.nextFree()
+            code += translateExpression(binExpr.left, resultRegister, -1)
+            code += translateExpression(binExpr.right, rightResultReg, -1)
+            code += VmCodeInstruction(Opcode.ORR, 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()
+        if(binExpr.right is PtNumber) {
+            code += translateExpression(binExpr.left, resultRegister, -1)
+            code += VmCodeInstruction(Opcode.MOD, vmDt, reg1 = resultRegister, value=(binExpr.right as PtNumber).number.toInt())
+        } else {
+            code += translateExpression(binExpr.left, resultRegister, -1)
+            code += translateExpression(binExpr.right, rightResultReg, -1)
+            code += VmCodeInstruction(Opcode.MODR, 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.DIVSR, vmDt, fpReg1 = resultFpRegister, fpReg2=rightResultFpReg)
+                else
+                    VmCodeInstruction(Opcode.DIVR, 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()
+                if(binExpr.right is PtNumber) {
+                    code += translateExpression(binExpr.left, resultRegister, -1)
+                    code += if (signed)
+                        VmCodeInstruction(Opcode.DIVS, vmDt, reg1 = resultRegister, value=(binExpr.right as PtNumber).number.toInt())
+                    else
+                        VmCodeInstruction(Opcode.DIV, vmDt, reg1 = resultRegister, value=(binExpr.right as PtNumber).number.toInt())
+                } else {
+                    code += translateExpression(binExpr.left, resultRegister, -1)
+                    code += translateExpression(binExpr.right, rightResultReg, -1)
+                    code += if (signed)
+                        VmCodeInstruction(Opcode.DIVSR, vmDt, reg1 = resultRegister, reg2 = rightResultReg)
+                    else
+                        VmCodeInstruction(Opcode.DIVR, 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.MULR, 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.MULR, 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 {
+                if(binExpr.right is PtNumber) {
+                    code += translateExpression(binExpr.left, -1, resultFpRegister)
+                    code += VmCodeInstruction(Opcode.SUB, vmDt, fpReg1 = resultFpRegister, fpValue = (binExpr.right as PtNumber).number.toFloat())
+                } else {
+                    val rightResultFpReg = codeGen.vmRegisters.nextFreeFloat()
+                    code += translateExpression(binExpr.left, -1, resultFpRegister)
+                    code += translateExpression(binExpr.right, -1, rightResultFpReg)
+                    code += VmCodeInstruction(Opcode.SUBR, 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 {
+                if(binExpr.right is PtNumber) {
+                    code += translateExpression(binExpr.left, resultRegister, -1)
+                    code += VmCodeInstruction(Opcode.SUB, vmDt, reg1 = resultRegister, value = (binExpr.right as PtNumber).number.toInt())
+                } else {
+                    val rightResultReg = codeGen.vmRegisters.nextFree()
+                    code += translateExpression(binExpr.left, resultRegister, -1)
+                    code += translateExpression(binExpr.right, rightResultReg, -1)
+                    code += VmCodeInstruction(Opcode.SUBR, 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 {
+                if(binExpr.right is PtNumber) {
+                    code += translateExpression(binExpr.left, -1, resultFpRegister)
+                    code += VmCodeInstruction(Opcode.ADD, vmDt, fpReg1 = resultFpRegister, fpValue = (binExpr.right as PtNumber).number.toFloat())
+                } else {
+                    val rightResultFpReg = codeGen.vmRegisters.nextFreeFloat()
+                    code += translateExpression(binExpr.left, -1, resultFpRegister)
+                    code += translateExpression(binExpr.right, -1, rightResultFpReg)
+                    code += VmCodeInstruction(Opcode.ADDR, 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 {
+                if(binExpr.right is PtNumber) {
+                    code += translateExpression(binExpr.left, resultRegister, -1)
+                    code += VmCodeInstruction(Opcode.ADD, vmDt, reg1 = resultRegister, value=(binExpr.right as PtNumber).number.toInt())
+                } else {
+                    val rightResultReg = codeGen.vmRegisters.nextFree()
+                    code += translateExpression(binExpr.left, resultRegister, -1)
+                    code += translateExpression(binExpr.right, rightResultReg, -1)
+                    code += VmCodeInstruction(Opcode.ADDR, 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 +1,103 @@
+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) {
+
+    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
+        }
+        for (memvar in st.allMemMappedVariables) {
+            // TODO virtual machine doesn't have memory mapped variables, so treat them as regular allocated variables for now
+            val memsize =
+                when (memvar.dt) {
+                    in NumericDatatypes -> program.memsizer.memorySize(memvar.dt)
+                    in ArrayDatatypes -> program.memsizer.memorySize(memvar.dt, memvar.length!!)
+                    else -> throw InternalCompilerException("weird dt")
+                }
+
+            allocations[memvar.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]
+}

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

@@ -0,0 +1,189 @@
+package prog8.codegen.virtual
+
+import prog8.vm.Instruction
+import prog8.vm.Opcode
+import prog8.vm.VmDataType
+
+internal class VmOptimizerException(msg: String): Exception(msg)
+
+
+class VmPeepholeOptimizer(private val vmprog: AssemblyProgram, private val allocations: VariableAllocator) {
+    fun optimize() {
+        vmprog.getBlocks().forEach { block ->
+            do {
+                val indexedInstructions = block.lines.withIndex()
+                    .filter { it.value is VmCodeInstruction }
+                    .map { IndexedValue(it.index, (it.value as VmCodeInstruction).ins) }
+                val changed = removeNops(block, indexedInstructions)
+                        || removeDoubleLoadsAndStores(block, indexedInstructions)       // TODO not yet implemented
+                        || removeUselessArithmetic(block, indexedInstructions)
+                        || removeWeirdBranches(block, indexedInstructions)
+                        || removeDoubleSecClc(block, indexedInstructions)
+                        || cleanupPushPop(block, indexedInstructions)
+                // TODO other optimizations:
+                //  more complex optimizations such as unused registers
+            } while(changed)
+        }
+    }
+
+    private fun cleanupPushPop(block: VmCodeChunk, indexedInstructions: List<IndexedValue<Instruction>>): Boolean {
+        //  push followed by pop to same target, or different target->replace with load
+        var changed = false
+        indexedInstructions.reversed().forEach { (idx, ins) ->
+            if(ins.opcode==Opcode.PUSH) {
+                if(idx < block.lines.size-1) {
+                    val insAfter = block.lines[idx+1] as? VmCodeInstruction
+                    if(insAfter!=null && insAfter.ins.opcode ==Opcode.POP) {
+                        if(ins.reg1==insAfter.ins.reg1) {
+                            block.lines.removeAt(idx)
+                            block.lines.removeAt(idx)
+                        } else {
+                            block.lines[idx] = VmCodeInstruction(Opcode.LOADR, ins.type, reg1=insAfter.ins.reg1, reg2=ins.reg1)
+                            block.lines.removeAt(idx+1)
+                        }
+                        changed = true
+                    }
+                }
+            }
+        }
+        return changed
+    }
+
+
+    private fun removeDoubleSecClc(block: VmCodeChunk, indexedInstructions: List<IndexedValue<Instruction>>): Boolean {
+        //  double sec, clc
+        //  sec+clc or clc+sec
+        var changed = false
+        indexedInstructions.reversed().forEach { (idx, ins) ->
+            if(ins.opcode==Opcode.SEC || ins.opcode==Opcode.CLC) {
+                if(idx < block.lines.size-1) {
+                    val insAfter = block.lines[idx+1] as? VmCodeInstruction
+                    if(insAfter?.ins?.opcode == ins.opcode) {
+                        block.lines.removeAt(idx)
+                        changed = true
+                    }
+                    else if(ins.opcode==Opcode.SEC && insAfter?.ins?.opcode==Opcode.CLC) {
+                        block.lines.removeAt(idx)
+                        changed = true
+                    }
+                    else if(ins.opcode==Opcode.CLC && insAfter?.ins?.opcode==Opcode.SEC) {
+                        block.lines.removeAt(idx)
+                        changed = true
+                    }
+                }
+            }
+        }
+        return changed
+    }
+
+    private fun removeWeirdBranches(block: VmCodeChunk, indexedInstructions: List<IndexedValue<Instruction>>): Boolean {
+        //  jump/branch to label immediately below
+        var changed = false
+        indexedInstructions.reversed().forEach { (idx, ins) ->
+            if(ins.opcode==Opcode.JUMP && ins.labelSymbol!=null) {
+                // if jumping to label immediately following this
+                if(idx < block.lines.size-1) {
+                    val label = block.lines[idx+1] as? VmCodeLabel
+                    if(label?.name == ins.labelSymbol) {
+                        block.lines.removeAt(idx)
+                        changed = true
+                    }
+                }
+            }
+        }
+        return changed
+    }
+
+    private fun removeUselessArithmetic(block: VmCodeChunk, indexedInstructions: List<IndexedValue<Instruction>>): Boolean {
+        // note: this is hard to solve for the non-immediate instructions atm because the values are loaded into registers first
+        var changed = false
+        indexedInstructions.reversed().forEach { (idx, ins) ->
+            when (ins.opcode) {
+                Opcode.DIV, Opcode.DIVS, Opcode.MUL, Opcode.MOD -> {
+                    if (ins.value == 1) {
+                        block.lines.removeAt(idx)
+                        changed = true
+                    }
+                }
+                Opcode.ADD, Opcode.SUB -> {
+                    if (ins.value == 1) {
+                        block.lines[idx] = VmCodeInstruction(
+                            if (ins.opcode == Opcode.ADD) Opcode.INC else Opcode.DEC,
+                            ins.type,
+                            ins.reg1
+                        )
+                        changed = true
+                    } else if (ins.value == 0) {
+                        block.lines.removeAt(idx)
+                        changed = true
+                    }
+                }
+                Opcode.AND -> {
+                    if (ins.value == 0) {
+                        block.lines[idx] = VmCodeInstruction(Opcode.LOAD, ins.type, reg1 = ins.reg1, value = 0)
+                        changed = true
+                    } else if (ins.value == 255 && ins.type == VmDataType.BYTE) {
+                        block.lines.removeAt(idx)
+                        changed = true
+                    } else if (ins.value == 65535 && ins.type == VmDataType.WORD) {
+                        block.lines.removeAt(idx)
+                        changed = true
+                    }
+                }
+                Opcode.OR -> {
+                    if (ins.value == 0) {
+                        block.lines.removeAt(idx)
+                        changed = true
+                    } else if ((ins.value == 255 && ins.type == VmDataType.BYTE) || (ins.value == 65535 && ins.type == VmDataType.WORD)) {
+                        block.lines[idx] = VmCodeInstruction(Opcode.LOAD, ins.type, reg1 = ins.reg1, value = ins.value)
+                        changed = true
+                    }
+                }
+                Opcode.XOR -> {
+                    if (ins.value == 0) {
+                        block.lines.removeAt(idx)
+                        changed = true
+                    }
+                }
+                else -> {}
+            }
+        }
+        return changed
+    }
+
+    private fun removeNops(block: VmCodeChunk, indexedInstructions: List<IndexedValue<Instruction>>): Boolean {
+        var changed = false
+        indexedInstructions.reversed().forEach { (idx, ins) ->
+            if (ins.opcode == Opcode.NOP) {
+                changed = true
+                block.lines.removeAt(idx)
+            }
+        }
+        return changed
+    }
+
+    private fun removeDoubleLoadsAndStores(block: VmCodeChunk, indexedInstructions: List<IndexedValue<Instruction>>): Boolean {
+        var changed = false
+        indexedInstructions.forEach { (idx, ins) ->
+
+            // TODO: detect multiple loads to the same target registers, only keep first (if source is not I/O memory)
+            // TODO: detect multiple stores to the same target, only keep first (if target is not I/O memory)
+            // TODO: detect multiple float ffrom/fto to the same target, only keep first
+            // TODO: detect multiple sequential rnd with same reg1, only keep one
+            // TODO: detect subsequent same xors/nots/negs, remove the pairs completely as they cancel out
+            // TODO: detect multiple same ands, ors; only keep first
+            // ...
+        }
+        return changed
+    }
+}
+
+private interface ICodeChange { // TODO not used? remove?
+    fun perform(block: VmCodeChunk)
+
+    class Remove(val idx: Int): ICodeChange {
+        override fun perform(block: VmCodeChunk) {
+            block.lines.removeAt(idx)
+        }
+    }
+}

codeGenVirtual/test/Dummies.kt

@@ -0,0 +1,19 @@
+package prog8tests.vm.helpers
+
+import prog8.code.core.*
+
+
+internal object DummyMemsizer : IMemSizer {
+    override fun memorySize(dt: DataType) = 0
+    override fun memorySize(arrayDt: DataType, numElements: Int) = 0
+}
+
+internal object DummyStringEncoder : IStringEncoding {
+    override fun encodeString(str: String, encoding: Encoding): List<UByte> {
+        return emptyList()
+    }
+
+    override fun decodeString(bytes: List<UByte>, encoding: Encoding): String {
+        return ""
+    }
+}

codeGenVirtual/test/TestVmPeepholeOpt.kt

@@ -0,0 +1,171 @@
+package prog8tests.vm
+
+import io.kotest.assertions.fail
+import io.kotest.core.spec.style.FunSpec
+import io.kotest.matchers.shouldBe
+import prog8.code.SymbolTable
+import prog8.code.ast.PtProgram
+import prog8.codegen.virtual.*
+import prog8.vm.Opcode
+import prog8.vm.VmDataType
+import prog8tests.vm.helpers.DummyMemsizer
+import prog8tests.vm.helpers.DummyStringEncoder
+
+class TestVmPeepholeOpt: FunSpec({
+    fun makeVmProgram(lines: List<VmCodeLine>): Pair<AssemblyProgram, VariableAllocator> {
+        val st = SymbolTable()
+        val program = PtProgram("test", DummyMemsizer, DummyStringEncoder)
+        val allocations = VariableAllocator(st, program)
+        val asm = AssemblyProgram("test", allocations)
+        val block = VmCodeChunk()
+        for(line in lines)
+            block += line
+        asm.addBlock(block)
+        return Pair(asm, allocations)
+    }
+
+    fun AssemblyProgram.lines(): List<VmCodeLine> = this.getBlocks().flatMap { it.lines }
+
+    test("remove nops") {
+        val(asm, allocations) = makeVmProgram(listOf(
+            VmCodeInstruction(Opcode.JUMP, labelSymbol = listOf("dummy")),
+            VmCodeInstruction(Opcode.NOP),
+            VmCodeInstruction(Opcode.NOP)
+        ))
+        asm.lines().size shouldBe 3
+        val opt = VmPeepholeOptimizer(asm, allocations)
+        opt.optimize()
+        asm.lines().size shouldBe 1
+    }
+
+    test("remove jmp to label below") {
+        val(asm, allocations) = makeVmProgram(listOf(
+            VmCodeInstruction(Opcode.JUMP, labelSymbol = listOf("label")),  // removed
+            VmCodeLabel(listOf("label")),
+            VmCodeInstruction(Opcode.JUMP, labelSymbol = listOf("label2")), // removed
+            VmCodeInstruction(Opcode.NOP),  // removed
+            VmCodeLabel(listOf("label2")),
+            VmCodeInstruction(Opcode.JUMP, labelSymbol = listOf("label3")),
+            VmCodeInstruction(Opcode.INC, VmDataType.BYTE, reg1=1),
+            VmCodeLabel(listOf("label3"))
+        ))
+        asm.lines().size shouldBe 8
+        val opt = VmPeepholeOptimizer(asm, allocations)
+        opt.optimize()
+        val lines = asm.lines()
+        lines.size shouldBe 5
+        (lines[0] as VmCodeLabel).name shouldBe listOf("label")
+        (lines[1] as VmCodeLabel).name shouldBe listOf("label2")
+        (lines[2] as VmCodeInstruction).ins.opcode shouldBe Opcode.JUMP
+        (lines[3] as VmCodeInstruction).ins.opcode shouldBe Opcode.INC
+        (lines[4] as VmCodeLabel).name shouldBe listOf("label3")
+    }
+
+    test("remove double sec/clc") {
+        val(asm, allocations) = makeVmProgram(listOf(
+            VmCodeInstruction(Opcode.SEC),
+            VmCodeInstruction(Opcode.SEC),
+            VmCodeInstruction(Opcode.SEC),
+            VmCodeInstruction(Opcode.CLC),
+            VmCodeInstruction(Opcode.CLC),
+            VmCodeInstruction(Opcode.CLC)
+        ))
+        asm.lines().size shouldBe 6
+        val opt = VmPeepholeOptimizer(asm, allocations)
+        opt.optimize()
+        val lines = asm.lines()
+        lines.size shouldBe 1
+        (lines[0] as VmCodeInstruction).ins.opcode shouldBe Opcode.CLC
+    }
+
+    test("push followed by pop") {
+        val(asm, allocations) = makeVmProgram(listOf(
+            VmCodeInstruction(Opcode.PUSH, VmDataType.BYTE, reg1=42),
+            VmCodeInstruction(Opcode.POP, VmDataType.BYTE, reg1=42),
+            VmCodeInstruction(Opcode.PUSH, VmDataType.BYTE, reg1=99),
+            VmCodeInstruction(Opcode.POP, VmDataType.BYTE, reg1=222)
+        ))
+        asm.lines().size shouldBe 4
+        val opt = VmPeepholeOptimizer(asm, allocations)
+        opt.optimize()
+        val lines = asm.lines()
+        lines.size shouldBe 1
+        (lines[0] as VmCodeInstruction).ins.opcode shouldBe Opcode.LOADR
+        (lines[0] as VmCodeInstruction).ins.reg1 shouldBe 222
+        (lines[0] as VmCodeInstruction).ins.reg2 shouldBe 99
+    }
+
+    test("remove useless div/mul, add/sub") {
+        val(asm, allocations) = makeVmProgram(listOf(
+            VmCodeInstruction(Opcode.DIV, VmDataType.BYTE, reg1=42, value = 1),
+            VmCodeInstruction(Opcode.DIVS, VmDataType.BYTE, reg1=42, value = 1),
+            VmCodeInstruction(Opcode.MUL, VmDataType.BYTE, reg1=42, value = 1),
+            VmCodeInstruction(Opcode.MOD, VmDataType.BYTE, reg1=42, value = 1),
+            VmCodeInstruction(Opcode.DIV, VmDataType.BYTE, reg1=42, value = 2),
+            VmCodeInstruction(Opcode.DIVS, VmDataType.BYTE, reg1=42, value = 2),
+            VmCodeInstruction(Opcode.MUL, VmDataType.BYTE, reg1=42, value = 2),
+            VmCodeInstruction(Opcode.MOD, VmDataType.BYTE, reg1=42, value = 2),
+            VmCodeInstruction(Opcode.ADD, VmDataType.BYTE, reg1=42, value = 0),
+            VmCodeInstruction(Opcode.SUB, VmDataType.BYTE, reg1=42, value = 0)
+        ))
+        asm.lines().size shouldBe 10
+        val opt = VmPeepholeOptimizer(asm, allocations)
+        opt.optimize()
+        val lines = asm.lines()
+        lines.size shouldBe 4
+    }
+
+    test("replace add/sub 1 by inc/dec") {
+        val(asm, allocations) = makeVmProgram(listOf(
+            VmCodeInstruction(Opcode.ADD, VmDataType.BYTE, reg1=42, value = 1),
+            VmCodeInstruction(Opcode.SUB, VmDataType.BYTE, reg1=42, value = 1)
+        ))
+        asm.lines().size shouldBe 2
+        val opt = VmPeepholeOptimizer(asm, allocations)
+        opt.optimize()
+        val lines = asm.lines()
+        lines.size shouldBe 2
+        (lines[0] as VmCodeInstruction).ins.opcode shouldBe Opcode.INC
+        (lines[1] as VmCodeInstruction).ins.opcode shouldBe Opcode.DEC
+    }
+
+    test("remove useless and/or/xor") {
+        val(asm, allocations) = makeVmProgram(listOf(
+            VmCodeInstruction(Opcode.AND, VmDataType.BYTE, reg1=42, value = 255),
+            VmCodeInstruction(Opcode.AND, VmDataType.WORD, reg1=42, value = 65535),
+            VmCodeInstruction(Opcode.OR, VmDataType.BYTE, reg1=42, value = 0),
+            VmCodeInstruction(Opcode.XOR, VmDataType.BYTE, reg1=42, value = 0),
+            VmCodeInstruction(Opcode.AND, VmDataType.BYTE, reg1=42, value = 200),
+            VmCodeInstruction(Opcode.AND, VmDataType.WORD, reg1=42, value = 60000),
+            VmCodeInstruction(Opcode.OR, VmDataType.BYTE, reg1=42, value = 1),
+            VmCodeInstruction(Opcode.XOR, VmDataType.BYTE, reg1=42, value = 1)
+        ))
+        asm.lines().size shouldBe 8
+        val opt = VmPeepholeOptimizer(asm, allocations)
+        opt.optimize()
+        val lines = asm.lines()
+        lines.size shouldBe 4
+    }
+
+    test("replace and/or/xor by constant number") {
+        val(asm, allocations) = makeVmProgram(listOf(
+            VmCodeInstruction(Opcode.AND, VmDataType.BYTE, reg1=42, value = 0),
+            VmCodeInstruction(Opcode.AND, VmDataType.WORD, reg1=42, value = 0),
+            VmCodeInstruction(Opcode.OR, VmDataType.BYTE, reg1=42, value = 255),
+            VmCodeInstruction(Opcode.OR, VmDataType.WORD, reg1=42, value = 65535)
+        ))
+        asm.lines().size shouldBe 4
+        val opt = VmPeepholeOptimizer(asm, allocations)
+        opt.optimize()
+        val lines = asm.lines()
+        lines.size shouldBe 4
+        (lines[0] as VmCodeInstruction).ins.opcode shouldBe Opcode.LOAD
+        (lines[1] as VmCodeInstruction).ins.opcode shouldBe Opcode.LOAD
+        (lines[2] as VmCodeInstruction).ins.opcode shouldBe Opcode.LOAD
+        (lines[3] as VmCodeInstruction).ins.opcode shouldBe Opcode.LOAD
+        (lines[0] as VmCodeInstruction).ins.value shouldBe 0
+        (lines[1] as VmCodeInstruction).ins.value shouldBe 0
+        (lines[2] as VmCodeInstruction).ins.value shouldBe 255
+        (lines[3] as VmCodeInstruction).ins.value shouldBe 65535
+    }
+})

codeOptimizers/build.gradle

@@ -24,7 +24,7 @@ compileTestKotlin {
 }
 
 dependencies {
-    implementation project(':compilerInterfaces')
+    implementation project(':codeCore')
     implementation project(':compilerAst')
     implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8"
     // implementation "org.jetbrains.kotlin:kotlin-reflect"

codeOptimizers/codeOptimizers.iml

@@ -9,7 +9,7 @@
     <orderEntry type="inheritedJdk" />
     <orderEntry type="sourceFolder" forTests="false" />
     <orderEntry type="library" name="KotlinJavaRuntime" level="project" />
-    <orderEntry type="module" module-name="compilerInterfaces" />
+    <orderEntry type="module" module-name="codeCore" />
     <orderEntry type="module" module-name="compilerAst" />
   </component>
 </module>

codeOptimizers/src/prog8/optimizer/BinExprSplitter.kt

@@ -3,8 +3,6 @@ package prog8.optimizer
 import prog8.ast.IStatementContainer
 import prog8.ast.Node
 import prog8.ast.Program
-import prog8.ast.base.DataType
-import prog8.ast.expressions.AugmentAssignmentOperators
 import prog8.ast.expressions.BinaryExpression
 import prog8.ast.expressions.IdentifierReference
 import prog8.ast.expressions.TypecastExpression
@@ -14,15 +12,19 @@ import prog8.ast.statements.Assignment
 import prog8.ast.statements.AssignmentOrigin
 import prog8.ast.walk.AstWalker
 import prog8.ast.walk.IAstModification
-import prog8.compilerinterface.CompilationOptions
-import prog8.compilerinterface.ICompilationTarget
-import prog8.compilerinterface.isIOAddress
+import prog8.code.core.AugmentAssignmentOperators
+import prog8.code.core.CompilationOptions
+import prog8.code.core.DataType
+import prog8.code.target.VMTarget
 
 
-class BinExprSplitter(private val program: Program, private val options: CompilationOptions, private val compTarget: ICompilationTarget) : AstWalker() {
+class BinExprSplitter(private val program: Program, private val options: CompilationOptions) : AstWalker() {
 
     override fun after(assignment: Assignment, parent: Node): Iterable<IAstModification> {
 
+        if(options.compTarget.name == VMTarget.NAME)
+            return noModifications  // don't split expressions when targeting the vm codegen, it handles nested expressions well
+
         if(assignment.value.inferType(program) istype DataType.FLOAT && !options.optimizeFloatExpressions)
             return noModifications
 
@@ -93,19 +95,20 @@ X =      BinExpr                                    X   =   LeftExpr
         val typecast = assignment.value as? TypecastExpression
         if(typecast!=null) {
             val origExpr = typecast.expression as? BinaryExpression
-            if(origExpr!=null) {
+            if(origExpr!=null && options.compTarget.name!=VMTarget.NAME) {
                 // it's a typecast of a binary expression.
                 // we can see if we can unwrap the binary expression by working on a new temporary variable
                 // (that has the type of the expression), and then finally doing the typecast.
                 // Once it's outside the typecast, the regular splitting can commence.
-                val tempVar = program.getTempVar(origExpr.inferType(program).getOr(DataType.UNDEFINED))
+                val tempvarDt = origExpr.inferType(program).getOr(DataType.UNDEFINED)
+                val (tempVarName, _) = program.getTempVar(tempvarDt)
                 val assignTempVar = Assignment(
-                    AssignTarget(IdentifierReference(tempVar, typecast.position), null, null, typecast.position),
+                    AssignTarget(IdentifierReference(tempVarName, typecast.position), null, null, typecast.position),
                     typecast.expression, AssignmentOrigin.OPTIMIZER, typecast.position
                 )
                 return listOf(
                     IAstModification.InsertBefore(assignment, assignTempVar, parent as IStatementContainer),
-                    IAstModification.ReplaceNode(typecast.expression, IdentifierReference(tempVar, typecast.position), typecast)
+                    IAstModification.ReplaceNode(typecast.expression, IdentifierReference(tempVarName, typecast.position), typecast)
                 )
             }
         }
@@ -115,7 +118,7 @@ X =      BinExpr                                    X   =   LeftExpr
 
     private fun isSimpleTarget(target: AssignTarget) =
             if (target.identifier!=null || target.memoryAddress!=null)
-                !target.isIOAddress(compTarget.machine)
+                !target.isIOAddress(options.compTarget.machine)
             else
                 false
 

codeOptimizers/src/prog8/optimizer/ConstExprEvaluator.kt

@@ -1,9 +1,12 @@
 package prog8.optimizer
 
-import prog8.ast.base.*
+import prog8.ast.base.ExpressionError
+import prog8.ast.base.FatalAstException
 import prog8.ast.expressions.Expression
 import prog8.ast.expressions.NumericLiteral
-import kotlin.math.pow
+import prog8.code.core.DataType
+import prog8.code.core.IntegerDatatypes
+import prog8.code.core.Position
 
 
 class ConstExprEvaluator {
@@ -16,13 +19,9 @@ class ConstExprEvaluator {
                 "*" -> multiply(left, right)
                 "/" -> divide(left, right)
                 "%" -> remainder(left, right)
-                "**" -> power(left, right)
                 "&" -> bitwiseand(left, right)
                 "|" -> bitwiseor(left, right)
                 "^" -> bitwisexor(left, right)
-                "and" -> logicaland(left, right)
-                "or" -> logicalor(left, right)
-                "xor" -> logicalxor(left, right)
                 "<" -> NumericLiteral.fromBoolean(left < right, left.position)
                 ">" -> NumericLiteral.fromBoolean(left > right, left.position)
                 "<=" -> NumericLiteral.fromBoolean(left <= right, left.position)
@@ -56,57 +55,6 @@ class ConstExprEvaluator {
         return NumericLiteral(left.type, result.toDouble(), left.position)
     }
 
-    private fun logicalxor(left: NumericLiteral, right: NumericLiteral): NumericLiteral {
-        val error = "cannot compute $left locical-bitxor $right"
-        return when (left.type) {
-            in IntegerDatatypes -> when (right.type) {
-                in IntegerDatatypes -> NumericLiteral.fromBoolean((left.number.toInt() != 0) xor (right.number.toInt() != 0), left.position)
-                DataType.FLOAT -> NumericLiteral.fromBoolean((left.number.toInt() != 0) xor (right.number != 0.0), left.position)
-                else -> throw ExpressionError(error, left.position)
-            }
-            DataType.FLOAT -> when (right.type) {
-                in IntegerDatatypes -> NumericLiteral.fromBoolean((left.number != 0.0) xor (right.number.toInt() != 0), left.position)
-                DataType.FLOAT -> NumericLiteral.fromBoolean((left.number != 0.0) xor (right.number != 0.0), left.position)
-                else -> throw ExpressionError(error, left.position)
-            }
-            else -> throw ExpressionError(error, left.position)
-        }
-    }
-
-    private fun logicalor(left: NumericLiteral, right: NumericLiteral): NumericLiteral {
-        val error = "cannot compute $left locical-or $right"
-        return when (left.type) {
-            in IntegerDatatypes -> when (right.type) {
-                in IntegerDatatypes -> NumericLiteral.fromBoolean(left.number.toInt() != 0 || right.number.toInt() != 0, left.position)
-                DataType.FLOAT -> NumericLiteral.fromBoolean(left.number.toInt() != 0 || right.number != 0.0, left.position)
-                else -> throw ExpressionError(error, left.position)
-            }
-            DataType.FLOAT -> when (right.type) {
-                in IntegerDatatypes -> NumericLiteral.fromBoolean(left.number != 0.0 || right.number.toInt() != 0, left.position)
-                DataType.FLOAT -> NumericLiteral.fromBoolean(left.number != 0.0 || right.number != 0.0, left.position)
-                else -> throw ExpressionError(error, left.position)
-            }
-            else -> throw ExpressionError(error, left.position)
-        }
-    }
-
-    private fun logicaland(left: NumericLiteral, right: NumericLiteral): NumericLiteral {
-        val error = "cannot compute $left locical-and $right"
-        return when (left.type) {
-            in IntegerDatatypes -> when (right.type) {
-                in IntegerDatatypes -> NumericLiteral.fromBoolean(left.number.toInt() != 0 && right.number.toInt() != 0, left.position)
-                DataType.FLOAT -> NumericLiteral.fromBoolean(left.number.toInt() != 0 && right.number != 0.0, left.position)
-                else -> throw ExpressionError(error, left.position)
-            }
-            DataType.FLOAT -> when (right.type) {
-                in IntegerDatatypes -> NumericLiteral.fromBoolean(left.number != 0.0 && right.number.toInt() != 0, left.position)
-                DataType.FLOAT -> NumericLiteral.fromBoolean(left.number != 0.0 && right.number != 0.0, left.position)
-                else -> throw ExpressionError(error, left.position)
-            }
-            else -> throw ExpressionError(error, left.position)
-        }
-    }
-
     private fun bitwisexor(left: NumericLiteral, right: NumericLiteral): NumericLiteral {
         if(left.type== DataType.UBYTE) {
             if(right.type in IntegerDatatypes) {
@@ -146,23 +94,6 @@ class ConstExprEvaluator {
         throw ExpressionError("cannot calculate $left & $right", left.position)
     }
 
-    private fun power(left: NumericLiteral, right: NumericLiteral): NumericLiteral {
-        val error = "cannot calculate $left ** $right"
-        return when (left.type) {
-            in IntegerDatatypes -> when (right.type) {
-                in IntegerDatatypes -> NumericLiteral.optimalNumeric(left.number.toInt().toDouble().pow(right.number.toInt()), left.position)
-                DataType.FLOAT -> NumericLiteral(DataType.FLOAT, left.number.toInt().toDouble().pow(right.number), left.position)
-                else -> throw ExpressionError(error, left.position)
-            }
-            DataType.FLOAT -> when (right.type) {
-                in IntegerDatatypes -> NumericLiteral(DataType.FLOAT, left.number.pow(right.number.toInt()), left.position)
-                DataType.FLOAT -> NumericLiteral(DataType.FLOAT, left.number.pow(right.number), left.position)
-                else -> throw ExpressionError(error, left.position)
-            }
-            else -> throw ExpressionError(error, left.position)
-        }
-    }
-
     private fun plus(left: NumericLiteral, right: NumericLiteral): NumericLiteral {
         val error = "cannot add $left and $right"
         return when (left.type) {

codeOptimizers/src/prog8/optimizer/ConstantFoldingOptimizer.kt

@@ -1,15 +1,15 @@
 package prog8.optimizer
 
-import prog8.ast.Node
-import prog8.ast.Program
-import prog8.ast.base.*
+import prog8.ast.*
+import prog8.ast.base.FatalAstException
+import prog8.ast.base.UndefinedSymbolError
 import prog8.ast.expressions.*
-import prog8.ast.statements.Assignment
-import prog8.ast.statements.ForLoop
-import prog8.ast.statements.VarDecl
+import prog8.ast.statements.*
 import prog8.ast.walk.AstWalker
 import prog8.ast.walk.IAstModification
-import kotlin.math.pow
+import prog8.code.core.AssociativeOperators
+import prog8.code.core.DataType
+import prog8.compiler.BuiltinFunctions
 
 
 class ConstantFoldingOptimizer(private val program: Program) : AstWalker() {
@@ -31,59 +31,8 @@ class ConstantFoldingOptimizer(private val program: Program) : AstWalker() {
     }
 
     override fun after(expr: PrefixExpression, parent: Node): Iterable<IAstModification> {
-        // Try to turn a unary prefix expression into a single constant value.
-        // Compile-time constant sub expressions will be evaluated on the spot.
-        // For instance, the expression for "- 4.5" will be optimized into the float literal -4.5
-        val subexpr = expr.expression
-        if (subexpr is NumericLiteral) {
-            // accept prefixed literal values (such as -3, not true)
-            return when (expr.operator) {
-                "+" -> listOf(IAstModification.ReplaceNode(expr, subexpr, parent))
-                "-" -> when (subexpr.type) {
-                    in IntegerDatatypes -> {
-                        listOf(IAstModification.ReplaceNode(expr,
-                                NumericLiteral.optimalInteger(-subexpr.number.toInt(), subexpr.position),
-                                parent))
-                    }
-                    DataType.FLOAT -> {
-                        listOf(IAstModification.ReplaceNode(expr,
-                                NumericLiteral(DataType.FLOAT, -subexpr.number, subexpr.position),
-                                parent))
-                    }
-                    else -> throw ExpressionError("can only take negative of int or float", subexpr.position)
-                }
-                "~" -> when (subexpr.type) {
-                    DataType.BYTE -> {
-                        listOf(IAstModification.ReplaceNode(expr,
-                                NumericLiteral(DataType.BYTE, subexpr.number.toInt().inv().toDouble(), subexpr.position),
-                                parent))
-                    }
-                    DataType.UBYTE -> {
-                        listOf(IAstModification.ReplaceNode(expr,
-                                NumericLiteral(DataType.UBYTE, (subexpr.number.toInt().inv() and 255).toDouble(), subexpr.position),
-                                parent))
-                    }
-                    DataType.WORD -> {
-                        listOf(IAstModification.ReplaceNode(expr,
-                                NumericLiteral(DataType.WORD, subexpr.number.toInt().inv().toDouble(), subexpr.position),
-                                parent))
-                    }
-                    DataType.UWORD -> {
-                        listOf(IAstModification.ReplaceNode(expr,
-                                NumericLiteral(DataType.UWORD, (subexpr.number.toInt().inv() and 65535).toDouble(), subexpr.position),
-                                parent))
-                    }
-                    else -> throw ExpressionError("can only take bitwise inversion of int", subexpr.position)
-                }
-                "not" -> {
-                    listOf(IAstModification.ReplaceNode(expr,
-                            NumericLiteral.fromBoolean(subexpr.number == 0.0, subexpr.position),
-                            parent))
-                }
-                else -> throw ExpressionError(expr.operator, subexpr.position)
-            }
-        }
-        return noModifications
+        val constValue = expr.constValue(program) ?: return noModifications
+        return listOf(IAstModification.ReplaceNode(expr, constValue, parent))
     }
 
     /*
@@ -104,9 +53,32 @@ class ConstantFoldingOptimizer(private val program: Program) : AstWalker() {
      *        (X + c1) - c2  ->  X + (c1-c2)
      */
     override fun after(expr: BinaryExpression, parent: Node): Iterable<IAstModification> {
+        val modifications = mutableListOf<IAstModification>()
         val leftconst = expr.left.constValue(program)
         val rightconst = expr.right.constValue(program)
-        val modifications = mutableListOf<IAstModification>()
+
+        if(expr.left.inferType(program) istype DataType.STR) {
+            if(expr.operator=="+" && expr.left is StringLiteral && expr.right is StringLiteral) {
+                // concatenate two strings.
+                val leftString = expr.left as StringLiteral
+                val rightString = expr.right as StringLiteral
+                val concatenated = if(leftString.encoding==rightString.encoding) {
+                    leftString.value + rightString.value
+                } else {
+                    program.encoding.decodeString(
+                        program.encoding.encodeString(leftString.value, leftString.encoding) + program.encoding.encodeString(rightString.value, rightString.encoding),
+                        leftString.encoding)
+                }
+                val concatStr = StringLiteral(concatenated, leftString.encoding, expr.position)
+                return listOf(IAstModification.ReplaceNode(expr, concatStr, parent))
+            }
+            else if(expr.operator=="*" && rightconst!=null && expr.left is StringLiteral) {
+                // mutiply a string.
+                val part = expr.left as StringLiteral
+                val newStr = StringLiteral(part.value.repeat(rightconst.number.toInt()), part.encoding, expr.position)
+                return listOf(IAstModification.ReplaceNode(expr, newStr, parent))
+            }
+        }
 
         if(expr.operator=="==" && rightconst!=null) {
             val leftExpr = expr.left as? BinaryExpression
@@ -135,42 +107,6 @@ class ConstantFoldingOptimizer(private val program: Program) : AstWalker() {
             }
         }
 
-        if(expr.operator == "**" && leftconst!=null) {
-            // optimize various simple cases of ** :
-            //  optimize away 1 ** x into just 1 and 0 ** x into just 0
-            //  optimize 2 ** x into (1<<x)  if both operands are integer.
-            val leftDt = leftconst.inferType(program).getOr(DataType.UNDEFINED)
-            when (leftconst.number) {
-                0.0 -> {
-                    val value = NumericLiteral(leftDt, 0.0, expr.position)
-                    modifications += IAstModification.ReplaceNode(expr, value, parent)
-                }
-                1.0 -> {
-                    val value = NumericLiteral(leftDt, 1.0, expr.position)
-                    modifications += IAstModification.ReplaceNode(expr, value, parent)
-                }
-                2.0 -> {
-                    if(rightconst!=null) {
-                        val value = NumericLiteral(leftDt, 2.0.pow(rightconst.number), expr.position)
-                        modifications += IAstModification.ReplaceNode(expr, value, parent)
-                    } else {
-                        val rightDt = expr.right.inferType(program).getOr(DataType.UNDEFINED)
-                        if(leftDt in IntegerDatatypes && rightDt in IntegerDatatypes) {
-                            val targetDt =
-                                when (parent) {
-                                    is Assignment -> parent.target.inferType(program).getOr(DataType.UNDEFINED)
-                                    is VarDecl -> parent.datatype
-                                    else -> leftDt
-                                }
-                            val one = NumericLiteral(targetDt, 1.0, expr.position)
-                            val shift = BinaryExpression(one, "<<", expr.right, expr.position)
-                            modifications += IAstModification.ReplaceNode(expr, shift, parent)
-                        }
-                    }
-                }
-            }
-        }
-
         if(expr.inferType(program) istype DataType.FLOAT) {
             val subExpr: BinaryExpression? = when {
                 leftconst != null -> expr.right as? BinaryExpression
@@ -201,6 +137,21 @@ class ConstantFoldingOptimizer(private val program: Program) : AstWalker() {
             modifications += IAstModification.ReplaceNode(expr, result, parent)
         }
 
+        if(leftconst==null && rightconst!=null && rightconst.number<0.0) {
+            if (expr.operator == "-") {
+                // X - -1 ---> X + 1
+                val posNumber = NumericLiteral.optimalNumeric(-rightconst.number, rightconst.position)
+                val plusExpr = BinaryExpression(expr.left, "+", posNumber, expr.position)
+                return listOf(IAstModification.ReplaceNode(expr, plusExpr, parent))
+            }
+            else if (expr.operator == "+") {
+                // X + -1 ---> X - 1
+                val posNumber = NumericLiteral.optimalNumeric(-rightconst.number, rightconst.position)
+                val plusExpr = BinaryExpression(expr.left, "-", posNumber, expr.position)
+                return listOf(IAstModification.ReplaceNode(expr, plusExpr, parent))
+            }
+        }
+
 
         val leftBinExpr = expr.left as? BinaryExpression
         val rightBinExpr = expr.right as? BinaryExpression
@@ -311,7 +262,6 @@ class ConstantFoldingOptimizer(private val program: Program) : AstWalker() {
     }
 
     override fun after(functionCallExpr: FunctionCallExpression, parent: Node): Iterable<IAstModification> {
-        // the args of a fuction are constfolded via recursion already.
         val constvalue = functionCallExpr.constValue(program)
         return if(constvalue!=null)
             listOf(IAstModification.ReplaceNode(functionCallExpr, constvalue, parent))
@@ -319,6 +269,14 @@ class ConstantFoldingOptimizer(private val program: Program) : AstWalker() {
             noModifications
     }
 
+    override fun after(bfc: BuiltinFunctionCall, parent: Node): Iterable<IAstModification> {
+        val constvalue = bfc.constValue(program)
+        return if(constvalue!=null)
+            listOf(IAstModification.ReplaceNode(bfc, constvalue, parent))
+        else
+            noModifications
+    }
+
     override fun after(forLoop: ForLoop, parent: Node): Iterable<IAstModification> {
         fun adjustRangeDt(rangeFrom: NumericLiteral, targetDt: DataType, rangeTo: NumericLiteral, stepLiteral: NumericLiteral?, range: RangeExpression): RangeExpression? {
             val fromCast = rangeFrom.cast(targetDt)
@@ -427,12 +385,12 @@ class ConstantFoldingOptimizer(private val program: Program) : AstWalker() {
     {
         // NOTE: THIS IS ONLY VALID ON FLOATING POINT CONSTANTS
 
-        // todo: this implements only a small set of possible reorderings at this time, we could think of more
+        // TODO: this implements only a small set of possible reorderings at this time, we could think of more
         if(expr.operator==subExpr.operator) {
             // both operators are the same.
 
             // If associative,  we can simply shuffle the const operands around to optimize.
-            if(expr.operator in AssociativeOperators) {
+            if(expr.operator in AssociativeOperators && maySwapOperandOrder(expr)) {
                 return if(leftIsConst) {
                     if(subleftIsConst)
                         ShuffleOperands(expr, null, subExpr, subExpr.right, null, null, expr.left)