fix screencode encoding selection

that would generate wrong code if occurs at the end of a subroutine

.gitignore

@@ -1,7 +1,8 @@
 .idea/workspace.xml
-/build/
+.idea/discord.xml
-/dist/
+build/
-/output/
+dist/
+output/
 .*cache/
 *.directory
 *.prg
@@ -11,9 +12,9 @@
 *.vice-mon-list
 docs/build
 out/
-**/*.interp
+parser/**/*.interp
-**/*.tokens
+parser/**/*.tokens
-
+parser/**/*.java
 *.py[cod]
 *.egg
 *.egg-info
@@ -25,7 +26,9 @@ parser.out
 parsetab.py
 .pytest_cache/
 .attach_pid*
+compiler/lib/
 
 .gradle
-build/
 /prog8compiler.jar
+sd*.img
+*.d64

.idea/codeInsightSettings.xml

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

.idea/codeStyles/Project.xml

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

.idea/codeStyles/codeStyleConfig.xml

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

.idea/compiler.xml

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

.idea/inspectionProfiles/Project_Default.xml

@@ -1,6 +1,14 @@
 <component name="InspectionProjectProfileManager">
   <profile version="1.0">
     <option name="myName" value="Project Default" />
+    <inspection_tool class="DuplicatedCode" enabled="true" level="WEAK WARNING" enabled_by_default="true">
+      <Languages>
+        <language minSize="70" name="Kotlin" />
+        <language isEnabled="false" name="Groovy" />
+      </Languages>
+    </inspection_tool>
+    <inspection_tool class="IncompleteDestructuring" enabled="true" level="WARNING" enabled_by_default="true" />
+    <inspection_tool class="PyInterpreterInspection" enabled="false" level="WARNING" enabled_by_default="false" />
     <inspection_tool class="SpellCheckingInspection" enabled="true" level="TYPO" enabled_by_default="true">
       <option name="processCode" value="false" />
       <option name="processLiterals" value="true" />

.idea/kotlinc.xml

@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project version="4">
   <component name="Kotlin2JvmCompilerArguments">
-    <option name="jvmTarget" value="1.8" />
+    <option name="jvmTarget" value="11" />
   </component>
 </project>

.idea/libraries/antlr_4_7_2_complete.xml

@@ -1,9 +0,0 @@
-<component name="libraryTable">
-  <library name="antlr-4.7.2-complete">
-    <CLASSES>
-      <root url="jar://$PROJECT_DIR$/parser/antlr/lib/antlr-4.7.2-complete.jar!/" />
-    </CLASSES>
-    <JAVADOC />
-    <SOURCES />
-  </library>
-</component>

.idea/libraries/antlr_antlr4.xml

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

.idea/libraries/antlr_runtime_4_7_2.xml

@@ -1,9 +0,0 @@
-<component name="libraryTable">
-  <library name="antlr-runtime-4.7.2">
-    <CLASSES>
-      <root url="jar://$PROJECT_DIR$/parser/antlr/lib/antlr-runtime-4.7.2.jar!/" />
-    </CLASSES>
-    <JAVADOC />
-    <SOURCES />
-  </library>
-</component>

.idea/libraries/github_hypfvieh_dbus_java.xml

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

.idea/libraries/glassfish_javax_json.xml

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

.idea/libraries/io_kotest_assertions_core_jvm.xml

@@ -0,0 +1,22 @@
+<component name="libraryTable">
+  <library name="io.kotest.assertions.core.jvm" type="repository">
+    <properties maven-id="io.kotest:kotest-assertions-core-jvm:4.6.3" />
+    <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://$MAVEN_REPOSITORY$/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!/" />
+    </CLASSES>
+    <JAVADOC />
+    <SOURCES />
+  </library>
+</component>

.idea/libraries/io_kotest_property_jvm.xml

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

.idea/libraries/io_kotest_runner_junit5_jvm.xml

@@ -0,0 +1,56 @@
+<component name="libraryTable">
+  <library name="io.kotest.runner.junit5.jvm" type="repository">
+    <properties maven-id="io.kotest:kotest-runner-junit5-jvm:4.6.3" />
+    <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://$MAVEN_REPOSITORY$/com/github/ajalt/mordant/1.2.1/mordant-1.2.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/com/github/ajalt/colormath/1.2.0/colormath-1.2.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-script-util/1.5.0/kotlin-script-util-1.5.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/intellij/deps/trove4j/1.0.20181211/trove4j-1.0.20181211.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-daemon-client/1.5.0/kotlin-daemon-client-1.5.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-core/1.3.8/kotlinx-coroutines-core-1.3.8.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-scripting-jvm/1.5.0/kotlin-scripting-jvm-1.5.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-scripting-common/1.5.0/kotlin-scripting-common-1.5.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/opentest4j/opentest4j/1.2.0/opentest4j-1.2.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-framework-discovery-jvm/4.6.3/kotest-framework-discovery-jvm-4.6.3.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-core-jvm/4.6.3/kotest-assertions-core-jvm-4.6.3.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-jdk8/1.5.0/kotlinx-coroutines-jdk8-1.5.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-api-jvm/4.6.3/kotest-assertions-api-jvm-4.6.3.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-extensions-jvm/4.6.3/kotest-extensions-jvm-4.6.3.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/commons-io/commons-io/2.6/commons-io-2.6.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/mockk/mockk/1.9.3/mockk-1.9.3.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/mockk/mockk-common/1.9.3/mockk-common-1.9.3.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/mockk/mockk-dsl/1.9.3/mockk-dsl-1.9.3.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/mockk/mockk-dsl-jvm/1.9.3/mockk-dsl-jvm-1.9.3.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/mockk/mockk-agent-jvm/1.9.3/mockk-agent-jvm-1.9.3.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/mockk/mockk-agent-api/1.9.3/mockk-agent-api-1.9.3.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/mockk/mockk-agent-common/1.9.3/mockk-agent-common-1.9.3.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/objenesis/objenesis/3.0.1/objenesis-3.0.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/net/bytebuddy/byte-buddy/1.9.10/byte-buddy-1.9.10.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/net/bytebuddy/byte-buddy-agent/1.9.10/byte-buddy-agent-1.9.10.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-framework-concurrency-jvm/4.6.3/kotest-framework-concurrency-jvm-4.6.3.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-core-jvm/1.5.0/kotlinx-coroutines-core-jvm-1.5.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-common/1.5.0/kotlin-stdlib-common-1.5.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/junit/platform/junit-platform-engine/1.6.2/junit-platform-engine-1.6.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/apiguardian/apiguardian-api/1.1.0/apiguardian-api-1.1.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/junit/platform/junit-platform-commons/1.6.2/junit-platform-commons-1.6.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/junit/platform/junit-platform-suite-api/1.6.2/junit-platform-suite-api-1.6.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/junit/platform/junit-platform-launcher/1.6.2/junit-platform-launcher-1.6.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/junit/jupiter/junit-jupiter-api/5.6.2/junit-jupiter-api-5.6.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk8/1.5.0/kotlin-stdlib-jdk8-1.5.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/1.5.0/kotlin-stdlib-1.5.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/annotations/13.0/annotations-13.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk7/1.5.0/kotlin-stdlib-jdk7-1.5.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-script-runtime/1.5.0/kotlin-script-runtime-1.5.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-reflect/1.5.0/kotlin-reflect-1.5.0.jar!/" />
+    </CLASSES>
+    <JAVADOC />
+    <SOURCES />
+  </library>
+</component>

.idea/libraries/jetbrains_kotlinx_cli_jvm.xml

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

.idea/libraries/michael_bull_kotlin_result_jvm.xml

@@ -0,0 +1,15 @@
+<component name="libraryTable">
+  <library name="michael.bull.kotlin.result.jvm" type="repository">
+    <properties maven-id="com.michael-bull.kotlin-result:kotlin-result-jvm:1.1.12" />
+    <CLASSES>
+      <root url="jar://$MAVEN_REPOSITORY$/com/michael-bull/kotlin-result/kotlin-result-jvm/1.1.12/kotlin-result-jvm-1.1.12.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk8/1.5.10/kotlin-stdlib-jdk8-1.5.10.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/1.5.10/kotlin-stdlib-1.5.10.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/annotations/13.0/annotations-13.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk7/1.5.10/kotlin-stdlib-jdk7-1.5.10.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-common/1.5.10/kotlin-stdlib-common-1.5.10.jar!/" />
+    </CLASSES>
+    <JAVADOC />
+    <SOURCES />
+  </library>
+</component>

.idea/libraries/slf4j_simple.xml

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

.idea/libraries/takes.xml

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

.idea/libraries/unittest_libs.xml

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

.idea/markdown-navigator-enh.xml

@@ -0,0 +1,29 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="MarkdownEnhProjectSettings">
+    <AnnotatorSettings targetHasSpaces="true" linkCaseMismatch="true" wikiCaseMismatch="true" wikiLinkHasDashes="true" notUnderWikiHome="true" targetNotWikiPageExt="true" notUnderSourceWikiHome="true" targetNameHasAnchor="true" targetPathHasAnchor="true" wikiLinkHasSlash="true" wikiLinkHasSubdir="true" wikiLinkHasOnlyAnchor="true" linkTargetsWikiHasExt="true" linkTargetsWikiHasBadExt="true" notUnderSameRepo="true" targetNotUnderVcs="false" linkNeedsExt="true" linkHasBadExt="true" linkTargetNeedsExt="true" linkTargetHasBadExt="true" wikiLinkNotInWiki="true" imageTargetNotInRaw="true" repoRelativeAcrossVcsRoots="true" multipleWikiTargetsMatch="true" unresolvedLinkReference="true" linkIsIgnored="true" anchorIsIgnored="true" anchorIsUnresolved="true" anchorLineReferenceIsUnresolved="true" anchorLineReferenceFormat="true" anchorHasDuplicates="true" abbreviationDuplicates="true" abbreviationNotUsed="true" attributeIdDuplicateDefinition="true" attributeIdNotUsed="true" footnoteDuplicateDefinition="true" footnoteUnresolved="true" footnoteDuplicates="true" footnoteNotUsed="true" macroDuplicateDefinition="true" macroUnresolved="true" macroDuplicates="true" macroNotUsed="true" referenceDuplicateDefinition="true" referenceUnresolved="true" referenceDuplicates="true" referenceNotUsed="true" referenceUnresolvedNumericId="true" enumRefDuplicateDefinition="true" enumRefUnresolved="true" enumRefDuplicates="true" enumRefNotUsed="true" enumRefLinkUnresolved="true" enumRefLinkDuplicates="true" simTocUpdateNeeded="true" simTocTitleSpaceNeeded="true" />
+    <HtmlExportSettings updateOnSave="false" parentDir="" targetDir="" cssDir="css" scriptDir="js" plainHtml="false" imageDir="" copyLinkedImages="false" imagePathType="0" targetPathType="2" targetExt="" useTargetExt="false" noCssNoScripts="false" useElementStyleAttribute="false" linkToExportedHtml="true" exportOnSettingsChange="true" regenerateOnProjectOpen="false" linkFormatType="HTTP_ABSOLUTE" />
+    <LinkMapSettings>
+      <textMaps />
+    </LinkMapSettings>
+  </component>
+  <component name="MarkdownNavigatorHistory">
+    <PasteImageHistory checkeredTransparentBackground="false" filename="image" directory="" onPasteImageTargetRef="3" onPasteLinkText="0" onPasteImageElement="1" onPasteLinkElement="1" onPasteReferenceElement="2" cornerRadius="20" borderColor="0" transparentColor="16777215" borderWidth="1" trimTop="0" trimBottom="0" trimLeft="0" trimRight="0" transparent="false" roundCorners="false" showPreview="true" bordered="false" scaled="false" cropped="false" hideInapplicableOperations="false" preserveLinkFormat="false" scale="50" scalingInterpolation="1" transparentTolerance="0" saveAsDefaultOnOK="false" linkFormat="0" addHighlights="false" showHighlightCoordinates="true" showHighlights="false" mouseSelectionAddsHighlight="false" outerFilled="false" outerFillColor="0" outerFillTransparent="true" outerFillAlpha="30">
+      <highlightList />
+      <directories />
+      <filenames />
+    </PasteImageHistory>
+    <CopyImageHistory checkeredTransparentBackground="false" filename="image" directory="" onPasteImageTargetRef="3" onPasteLinkText="0" onPasteImageElement="1" onPasteLinkElement="1" onPasteReferenceElement="2" cornerRadius="20" borderColor="0" transparentColor="16777215" borderWidth="1" trimTop="0" trimBottom="0" trimLeft="0" trimRight="0" transparent="false" roundCorners="false" showPreview="true" bordered="false" scaled="false" cropped="false" hideInapplicableOperations="false" preserveLinkFormat="false" scale="50" scalingInterpolation="1" transparentTolerance="0" saveAsDefaultOnOK="false" linkFormat="0" addHighlights="false" showHighlightCoordinates="true" showHighlights="false" mouseSelectionAddsHighlight="false" outerFilled="false" outerFillColor="0" outerFillTransparent="true" outerFillAlpha="30">
+      <highlightList />
+      <directories />
+      <filenames />
+    </CopyImageHistory>
+    <PasteLinkHistory onPasteImageTargetRef="3" onPasteTargetRef="1" onPasteLinkText="0" onPasteImageElement="1" onPasteLinkElement="1" onPasteWikiElement="2" onPasteReferenceElement="2" hideInapplicableOperations="false" preserveLinkFormat="false" useHeadingForLinkText="false" linkFormat="0" saveAsDefaultOnOK="false" />
+    <TableToJsonHistory>
+      <entries />
+    </TableToJsonHistory>
+    <TableSortHistory>
+      <entries />
+    </TableSortHistory>
+  </component>
+</project>

.idea/markdown-navigator.xml

@@ -0,0 +1,57 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="FlexmarkProjectSettings">
+    <FlexmarkHtmlSettings flexmarkSpecExampleRendering="0" flexmarkSpecExampleRenderHtml="false">
+      <flexmarkSectionLanguages>
+        <option name="1" value="Markdown" />
+        <option name="2" value="HTML" />
+        <option name="3" value="flexmark-ast:1" />
+      </flexmarkSectionLanguages>
+    </FlexmarkHtmlSettings>
+  </component>
+  <component name="MarkdownProjectSettings">
+    <PreviewSettings splitEditorLayout="SPLIT" splitEditorPreview="PREVIEW" useGrayscaleRendering="false" zoomFactor="1.0" maxImageWidth="0" synchronizePreviewPosition="true" highlightPreviewType="LINE" highlightFadeOut="5" highlightOnTyping="true" synchronizeSourcePosition="true" verticallyAlignSourceAndPreviewSyncPosition="true" showSearchHighlightsInPreview="true" showSelectionInPreview="true" lastLayoutSetsDefault="false">
+      <PanelProvider>
+        <provider providerId="com.vladsch.md.nav.editor.javafx.html.panel" providerName="JavaFX WebView" />
+      </PanelProvider>
+    </PreviewSettings>
+    <ParserSettings gitHubSyntaxChange="false" correctedInvalidSettings="false" emojiShortcuts="1" emojiImages="0">
+      <PegdownExtensions>
+        <option name="ANCHORLINKS" value="true" />
+        <option name="ATXHEADERSPACE" value="true" />
+        <option name="FENCED_CODE_BLOCKS" value="true" />
+        <option name="INTELLIJ_DUMMY_IDENTIFIER" value="true" />
+        <option name="RELAXEDHRULES" value="true" />
+        <option name="STRIKETHROUGH" value="true" />
+        <option name="TABLES" value="true" />
+        <option name="TASKLISTITEMS" value="true" />
+      </PegdownExtensions>
+      <ParserOptions>
+        <option name="COMMONMARK_LISTS" value="true" />
+        <option name="EMOJI_SHORTCUTS" value="true" />
+        <option name="GFM_TABLE_RENDERING" value="true" />
+        <option name="PRODUCTION_SPEC_PARSER" value="true" />
+        <option name="SIM_TOC_BLANK_LINE_SPACER" value="true" />
+      </ParserOptions>
+    </ParserSettings>
+    <HtmlSettings headerTopEnabled="false" headerBottomEnabled="false" bodyTopEnabled="false" bodyBottomEnabled="false" addPageHeader="false" imageUriSerials="false" addDocTypeHtml="true" noParaTags="false" plantUmlConversion="0">
+      <GeneratorProvider>
+        <provider providerId="com.vladsch.md.nav.editor.javafx.html.generator" providerName="JavaFx HTML Generator" />
+      </GeneratorProvider>
+      <headerTop />
+      <headerBottom />
+      <bodyTop />
+      <bodyBottom />
+    </HtmlSettings>
+    <CssSettings previewScheme="UI_SCHEME" cssUri="" isCssUriEnabled="false" isCssUriSerial="true" isCssTextEnabled="false" isDynamicPageWidth="true">
+      <StylesheetProvider>
+        <provider providerId="com.vladsch.md.nav.editor.javafx.html.css" providerName="Default JavaFx Stylesheet" />
+      </StylesheetProvider>
+      <ScriptProviders>
+        <provider providerId="com.vladsch.md.nav.editor.hljs.html.script" providerName="HighlightJS Script" />
+      </ScriptProviders>
+      <cssText />
+      <cssUriHistory />
+    </CssSettings>
+  </component>
+</project>

.idea/misc.xml

@@ -1,6 +1,25 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project version="4">
-  <component name="ProjectRootManager" version="2" languageLevel="JDK_1_8" default="false" project-jdk-name="Kotlin SDK" project-jdk-type="KotlinSDK">
+  <component name="ANTLRGenerationPreferences">
+    <option name="perGrammarGenerationSettings">
+      <list>
+        <PerGrammarGenerationSettings>
+          <option name="fileName" value="$PROJECT_DIR$/parser/antlr/Prog8ANTLR.g4" />
+          <option name="autoGen" value="true" />
+          <option name="outputDir" value="$PROJECT_DIR$/parser/src/prog8/parser" />
+          <option name="libDir" value="" />
+          <option name="encoding" value="" />
+          <option name="pkg" value="" />
+          <option name="language" value="" />
+          <option name="generateListener" value="false" />
+        </PerGrammarGenerationSettings>
+      </list>
+    </option>
+  </component>
+  <component name="FrameworkDetectionExcludesConfiguration">
+    <type id="Python" />
+  </component>
+  <component name="ProjectRootManager" version="2" languageLevel="JDK_11" project-jdk-name="11" project-jdk-type="JavaSDK">
     <output url="file://$PROJECT_DIR$/out" />
   </component>
 </project>

.idea/modules.xml

@@ -2,10 +2,15 @@
 <project version="4">
   <component name="ProjectModuleManager">
     <modules>
-      <module fileurl="file://$PROJECT_DIR$/DeprecatedStackVm/DeprecatedStackVm.iml" filepath="$PROJECT_DIR$/DeprecatedStackVm/DeprecatedStackVm.iml" />
+      <module fileurl="file://$PROJECT_DIR$/codeGeneration/codeGeneration.iml" filepath="$PROJECT_DIR$/codeGeneration/codeGeneration.iml" />
+      <module fileurl="file://$PROJECT_DIR$/codeOptimizers/codeOptimizers.iml" filepath="$PROJECT_DIR$/codeOptimizers/codeOptimizers.iml" />
       <module fileurl="file://$PROJECT_DIR$/compiler/compiler.iml" filepath="$PROJECT_DIR$/compiler/compiler.iml" />
+      <module fileurl="file://$PROJECT_DIR$/compilerAst/compilerAst.iml" filepath="$PROJECT_DIR$/compilerAst/compilerAst.iml" />
+      <module fileurl="file://$PROJECT_DIR$/compilerInterfaces/compilerInterfaces.iml" filepath="$PROJECT_DIR$/compilerInterfaces/compilerInterfaces.iml" />
+      <module fileurl="file://$PROJECT_DIR$/dbusCompilerService/dbusCompilerService.iml" filepath="$PROJECT_DIR$/dbusCompilerService/dbusCompilerService.iml" />
       <module fileurl="file://$PROJECT_DIR$/docs/docs.iml" filepath="$PROJECT_DIR$/docs/docs.iml" />
       <module fileurl="file://$PROJECT_DIR$/examples/examples.iml" filepath="$PROJECT_DIR$/examples/examples.iml" />
+      <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" />
     </modules>
   </component>

.idea/vcs.xml

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

.readthedocs.yaml

@@ -0,0 +1,29 @@
+# .readthedocs.yaml
+# Read the Docs configuration file
+# See https://docs.readthedocs.io/en/stable/config-file/v2.html for details
+
+# Required
+version: 2
+
+# Set the version of Python and other tools you might need
+build:
+  os: ubuntu-20.04
+  tools:
+    python: "3.9"
+    # You can also specify other tool versions:
+    # nodejs: "16"
+    # rust: "1.55"
+    # golang: "1.17"
+
+# Build documentation in the docs/ directory with Sphinx
+sphinx:
+  configuration: docs/source/conf.py
+
+# If using Sphinx, optionally build your docs in additional formats such as PDF
+formats:
+  - pdf
+
+# Optionally declare the Python requirements required to build your docs
+python:
+  install:
+    - requirements: docs/requirements.txt

.travis.yml

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

CompilerDevelopment.md

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

DeprecatedStackVm/src/compiler/intermediate/Instruction.kt

@@ -1,51 +0,0 @@
-package compiler.intermediate
-
-import prog8.vm.RuntimeValue
-import prog8.vm.stackvm.Syscall
-
-open class Instruction(val opcode: Opcode,
-                       val arg: RuntimeValue? = null,
-                       val arg2: RuntimeValue? = null,
-                       val callLabel: String? = null,
-                       val callLabel2: String? = null)
-{
-    var branchAddress: Int? = null
-
-    override fun toString(): String {
-        val argStr = arg?.toString() ?: ""
-        val result =
-                when {
-                    opcode== Opcode.LINE -> "_line  $callLabel"
-                    opcode== Opcode.INLINE_ASSEMBLY -> {
-                        // inline assembly is not written out (it can't be processed as intermediate language)
-                        // instead, it is converted into a system call that can be intercepted by the vm
-                        if(callLabel!=null)
-                            "syscall  SYSASM.$callLabel\n    return"
-                        else
-                            "inline_assembly"
-                    }
-                    opcode== Opcode.INCLUDE_FILE -> {
-                        "include_file \"$callLabel\" $arg $arg2"
-                    }
-                    opcode== Opcode.SYSCALL -> {
-                        val syscall = Syscall.values().find { it.callNr==arg!!.numericValue() }
-                        "syscall  $syscall"
-                    }
-                    opcode in opcodesWithVarArgument -> {
-                        // opcodes that manipulate a variable
-                        "${opcode.name.toLowerCase()}  ${callLabel?:""}  ${callLabel2?:""}".trimEnd()
-                    }
-                    callLabel==null -> "${opcode.name.toLowerCase()}  $argStr"
-                    else -> "${opcode.name.toLowerCase()}  $callLabel  $argStr"
-                }
-                .trimEnd()
-
-        return "    $result"
-    }
-}
-
-class LabelInstr(val name: String, val asmProc: Boolean) : Instruction(Opcode.NOP, null, null) {
-    override fun toString(): String {
-        return "\n$name:"
-    }
-}

DeprecatedStackVm/src/compiler/intermediate/IntermediateProgram.kt

@@ -1,548 +0,0 @@
-package compiler.intermediate
-
-import prog8.ast.antlr.escape
-import prog8.ast.base.*
-import prog8.ast.expressions.NumericLiteralValue
-import prog8.ast.expressions.ReferenceLiteralValue
-import prog8.ast.statements.StructDecl
-import prog8.ast.statements.VarDecl
-import prog8.ast.statements.ZeropageWish
-import prog8.compiler.CompilerException
-import prog8.compiler.HeapValues
-import prog8.compiler.Zeropage
-import prog8.compiler.ZeropageDepletedError
-import prog8.vm.RuntimeValue
-import java.io.PrintStream
-import java.nio.file.Path
-
-
-class IntermediateProgram(val name: String, var loadAddress: Int, val heap: HeapValues, val source: Path) {
-
-    class VariableParameters (val zp: ZeropageWish, val memberOfStruct: StructDecl?)
-    class Variable(val scopedname: String, val value: RuntimeValue, val params: VariableParameters)
-
-    class ProgramBlock(val name: String,
-                       var address: Int?,
-                       val instructions: MutableList<Instruction> = mutableListOf(),
-                       val variables: MutableList<Variable> = mutableListOf(),
-                       val memoryPointers: MutableMap<String, Pair<Int, DataType>> = mutableMapOf(),
-                       val labels: MutableMap<String, Instruction> = mutableMapOf(),        // names are fully scoped
-                       val force_output: Boolean)
-
-    val allocatedZeropageVariables = mutableMapOf<String, Pair<Int, DataType>>()
-    val blocks = mutableListOf<ProgramBlock>()
-    val memory = mutableMapOf<Int, List<RuntimeValue>>()
-    private lateinit var currentBlock: ProgramBlock
-
-    fun allocateZeropage(zeropage: Zeropage) {          // TODO not used anymore???
-        // allocates all @zp marked variables on the zeropage (for all blocks, as long as there is space in the ZP)
-        var notAllocated = 0
-        for(block in blocks) {
-            val zpVariables = block.variables.filter { it.params.zp==ZeropageWish.REQUIRE_ZEROPAGE || it.params.zp==ZeropageWish.PREFER_ZEROPAGE }
-            if (zpVariables.isNotEmpty()) {
-                for (variable in zpVariables) {
-                    if(variable.params.zp==ZeropageWish.NOT_IN_ZEROPAGE || variable.params.memberOfStruct!=null)
-                        throw CompilerException("zp conflict")
-                    try {
-                        val address = zeropage.allocate(variable.scopedname, variable.value.type, null)
-                        allocatedZeropageVariables[variable.scopedname] = Pair(address, variable.value.type)
-                    } catch (x: ZeropageDepletedError) {
-                        printWarning(x.toString() + " variable ${variable.scopedname} type ${variable.value.type}")
-                        notAllocated++
-                    }
-                }
-            }
-        }
-        if(notAllocated>0)
-            printWarning("$notAllocated variables marked for Zeropage could not be allocated there")
-    }
-
-    fun optimize() {
-        println("Optimizing stackVM code...")
-        // remove nops (that are not a label)
-        for (blk in blocks) {
-            blk.instructions.removeIf { it.opcode== Opcode.NOP && it !is LabelInstr }
-        }
-
-        optimizeDataConversionAndUselessDiscards()
-        optimizeVariableCopying()
-        optimizeMultipleSequentialLineInstrs()
-        optimizeCallReturnIntoJump()
-        optimizeConditionalBranches()
-        // todo: add more optimizations to intermediate code!
-
-        optimizeRemoveNops()    //  must be done as the last step
-        optimizeMultipleSequentialLineInstrs()      // once more
-        optimizeRemoveNops()    // once more
-    }
-
-    private fun optimizeConditionalBranches() {
-        // conditional branches that consume the value on the stack
-        // sometimes these are just constant values, so we can statically determine the branch
-        // or, they are preceded by a NOT instruction so we can simply remove that and flip the branch condition
-        val pushvalue = setOf(Opcode.PUSH_BYTE, Opcode.PUSH_WORD)
-        val notvalue = setOf(Opcode.NOT_BYTE, Opcode.NOT_WORD)
-        val branchOpcodes = setOf(Opcode.JZ, Opcode.JNZ, Opcode.JZW, Opcode.JNZW)
-        for(blk in blocks) {
-            val instructionsToReplace = mutableMapOf<Int, Instruction>()
-            blk.instructions.asSequence().withIndex().filter {it.value.opcode!= Opcode.LINE }.windowed(2).toList().forEach {
-                if (it[1].value.opcode in branchOpcodes) {
-                    if (it[0].value.opcode in pushvalue) {
-                        val value = it[0].value.arg!!.asBoolean
-                        instructionsToReplace[it[0].index] = Instruction(Opcode.NOP)
-                        val replacement: Instruction =
-                                if (value) {
-                                    when (it[1].value.opcode) {
-                                        Opcode.JNZ -> Instruction(Opcode.JUMP, callLabel = it[1].value.callLabel)
-                                        Opcode.JNZW -> Instruction(Opcode.JUMP, callLabel = it[1].value.callLabel)
-                                        else -> Instruction(Opcode.NOP)
-                                    }
-                                } else {
-                                    when (it[1].value.opcode) {
-                                        Opcode.JZ -> Instruction(Opcode.JUMP, callLabel = it[1].value.callLabel)
-                                        Opcode.JZW -> Instruction(Opcode.JUMP, callLabel = it[1].value.callLabel)
-                                        else -> Instruction(Opcode.NOP)
-                                    }
-                                }
-                        instructionsToReplace[it[1].index] = replacement
-                    }
-                    else if (it[0].value.opcode in notvalue) {
-                        instructionsToReplace[it[0].index] = Instruction(Opcode.NOP)
-                        val replacement: Instruction =
-                                when (it[1].value.opcode) {
-                                    Opcode.JZ -> Instruction(Opcode.JNZ, callLabel = it[1].value.callLabel)
-                                    Opcode.JZW -> Instruction(Opcode.JNZW, callLabel = it[1].value.callLabel)
-                                    Opcode.JNZ -> Instruction(Opcode.JZ, callLabel = it[1].value.callLabel)
-                                    Opcode.JNZW -> Instruction(Opcode.JZW, callLabel = it[1].value.callLabel)
-                                    else -> Instruction(Opcode.NOP)
-                                }
-                        instructionsToReplace[it[1].index] = replacement
-                    }
-                }
-            }
-
-            for (rins in instructionsToReplace) {
-                blk.instructions[rins.key] = rins.value
-            }
-        }
-    }
-
-    private fun optimizeRemoveNops() {
-        // remove nops (that are not a label)
-        for (blk in blocks)
-            blk.instructions.removeIf { it.opcode== Opcode.NOP && it !is LabelInstr }
-    }
-
-    private fun optimizeCallReturnIntoJump() {
-        // replaces call X followed by return, by jump X
-        for(blk in blocks) {
-            val instructionsToReplace = mutableMapOf<Int, Instruction>()
-
-            blk.instructions.asSequence().withIndex().filter {it.value.opcode!= Opcode.LINE }.windowed(2).toList().forEach {
-                if(it[0].value.opcode== Opcode.CALL && it[1].value.opcode== Opcode.RETURN) {
-                    instructionsToReplace[it[1].index] = Instruction(Opcode.JUMP, callLabel = it[0].value.callLabel)
-                    instructionsToReplace[it[0].index] = Instruction(Opcode.NOP)
-                }
-            }
-
-            for (rins in instructionsToReplace) {
-                blk.instructions[rins.key] = rins.value
-            }
-        }
-    }
-
-    private fun optimizeMultipleSequentialLineInstrs() {
-        for(blk in blocks) {
-            val instructionsToReplace = mutableMapOf<Int, Instruction>()
-
-            blk.instructions.asSequence().withIndex().windowed(2).toList().forEach {
-                if (it[0].value.opcode == Opcode.LINE && it[1].value.opcode == Opcode.LINE)
-                    instructionsToReplace[it[0].index] = Instruction(Opcode.NOP)
-            }
-
-            for (rins in instructionsToReplace) {
-                blk.instructions[rins.key] = rins.value
-            }
-        }
-    }
-
-    private fun optimizeVariableCopying() {
-        for(blk in blocks) {
-
-            val instructionsToReplace = mutableMapOf<Int, Instruction>()
-
-            blk.instructions.asSequence().withIndex().windowed(2).toList().forEach {
-                when (it[0].value.opcode) {
-                    Opcode.PUSH_VAR_BYTE ->
-                        if (it[1].value.opcode == Opcode.POP_VAR_BYTE) {
-                            if (it[0].value.callLabel == it[1].value.callLabel) {
-                                instructionsToReplace[it[0].index] = Instruction(Opcode.NOP)
-                                instructionsToReplace[it[1].index] = Instruction(Opcode.NOP)
-                            }
-                        }
-                    Opcode.PUSH_VAR_WORD ->
-                        if (it[1].value.opcode == Opcode.POP_VAR_WORD) {
-                            if (it[0].value.callLabel == it[1].value.callLabel) {
-                                instructionsToReplace[it[0].index] = Instruction(Opcode.NOP)
-                                instructionsToReplace[it[1].index] = Instruction(Opcode.NOP)
-                            }
-                        }
-                    Opcode.PUSH_VAR_FLOAT ->
-                        if (it[1].value.opcode == Opcode.POP_VAR_FLOAT) {
-                            if (it[0].value.callLabel == it[1].value.callLabel) {
-                                instructionsToReplace[it[0].index] = Instruction(Opcode.NOP)
-                                instructionsToReplace[it[1].index] = Instruction(Opcode.NOP)
-                            }
-                        }
-                    Opcode.PUSH_MEM_B, Opcode.PUSH_MEM_UB ->
-                        if(it[1].value.opcode == Opcode.POP_MEM_BYTE) {
-                            if(it[0].value.arg == it[1].value.arg) {
-                                instructionsToReplace[it[0].index] = Instruction(Opcode.NOP)
-                                instructionsToReplace[it[1].index] = Instruction(Opcode.NOP)
-                            }
-                        }
-                    Opcode.PUSH_MEM_W, Opcode.PUSH_MEM_UW ->
-                        if(it[1].value.opcode == Opcode.POP_MEM_WORD) {
-                            if(it[0].value.arg == it[1].value.arg) {
-                                instructionsToReplace[it[0].index] = Instruction(Opcode.NOP)
-                                instructionsToReplace[it[1].index] = Instruction(Opcode.NOP)
-                            }
-                        }
-                    Opcode.PUSH_MEM_FLOAT ->
-                        if(it[1].value.opcode == Opcode.POP_MEM_FLOAT) {
-                            if(it[0].value.arg == it[1].value.arg) {
-                                instructionsToReplace[it[0].index] = Instruction(Opcode.NOP)
-                                instructionsToReplace[it[1].index] = Instruction(Opcode.NOP)
-                            }
-                        }
-                    else -> {}
-                }
-            }
-
-            for (rins in instructionsToReplace) {
-                blk.instructions[rins.key] = rins.value
-            }
-        }
-    }
-
-    private fun optimizeDataConversionAndUselessDiscards() {
-        // - push value followed by a data type conversion -> push the value in the correct type and remove the conversion
-        // - push something followed by a discard -> remove both
-        val instructionsToReplace = mutableMapOf<Int, Instruction>()
-
-        fun optimizeDiscardAfterPush(index0: Int, index1: Int, ins1: Instruction) {
-            if (ins1.opcode == Opcode.DISCARD_FLOAT || ins1.opcode == Opcode.DISCARD_WORD || ins1.opcode == Opcode.DISCARD_BYTE) {
-                instructionsToReplace[index0] = Instruction(Opcode.NOP)
-                instructionsToReplace[index1] = Instruction(Opcode.NOP)
-            }
-        }
-
-        fun optimizeFloatConversion(index0: Int, index1: Int, ins1: Instruction) {
-            when (ins1.opcode) {
-                Opcode.DISCARD_FLOAT -> {
-                    instructionsToReplace[index0] = Instruction(Opcode.NOP)
-                    instructionsToReplace[index1] = Instruction(Opcode.NOP)
-                }
-                Opcode.DISCARD_BYTE, Opcode.DISCARD_WORD -> throw CompilerException("invalid discard type following a float")
-                else -> throw CompilerException("invalid conversion opcode ${ins1.opcode} following a float")
-            }
-        }
-
-        fun optimizeWordConversion(index0: Int, ins0: Instruction, index1: Int, ins1: Instruction) {
-            when (ins1.opcode) {
-                Opcode.CAST_UW_TO_B, Opcode.CAST_W_TO_B -> {
-                    val ins = Instruction(Opcode.PUSH_BYTE, ins0.arg!!.cast(DataType.BYTE))
-                    instructionsToReplace[index0] = ins
-                    instructionsToReplace[index1] = Instruction(Opcode.NOP)
-                }
-                Opcode.CAST_W_TO_UB, Opcode.CAST_UW_TO_UB -> {
-                    val ins = Instruction(Opcode.PUSH_BYTE, RuntimeValue(DataType.UBYTE, ins0.arg!!.integerValue() and 255))
-                    instructionsToReplace[index0] = ins
-                    instructionsToReplace[index1] = Instruction(Opcode.NOP)
-                }
-                Opcode.MSB -> {
-                    val ins = Instruction(Opcode.PUSH_BYTE, RuntimeValue(DataType.UBYTE, ins0.arg!!.integerValue() ushr 8 and 255))
-                    instructionsToReplace[index0] = ins
-                    instructionsToReplace[index1] = Instruction(Opcode.NOP)
-                }
-                Opcode.CAST_W_TO_F, Opcode.CAST_UW_TO_F -> {
-                    val ins = Instruction(Opcode.PUSH_FLOAT, RuntimeValue(DataType.FLOAT, ins0.arg!!.integerValue().toDouble()))
-                    instructionsToReplace[index0] = ins
-                    instructionsToReplace[index1] = Instruction(Opcode.NOP)
-                }
-                Opcode.CAST_UW_TO_W -> {
-                    val cv = ins0.arg!!.cast(DataType.WORD)
-                    instructionsToReplace[index0] = Instruction(Opcode.PUSH_WORD, cv)
-                    instructionsToReplace[index1] = Instruction(Opcode.NOP)
-                }
-                Opcode.CAST_W_TO_UW -> {
-                    val cv = ins0.arg!!.cast(DataType.UWORD)
-                    instructionsToReplace[index0] = Instruction(Opcode.PUSH_WORD, cv)
-                    instructionsToReplace[index1] = Instruction(Opcode.NOP)
-                }
-                Opcode.DISCARD_WORD -> {
-                    instructionsToReplace[index0] = Instruction(Opcode.NOP)
-                    instructionsToReplace[index1] = Instruction(Opcode.NOP)
-                }
-                Opcode.DISCARD_BYTE, Opcode.DISCARD_FLOAT -> throw CompilerException("invalid discard type following a byte")
-                else -> throw CompilerException("invalid conversion opcode ${ins1.opcode} following a word")
-            }
-        }
-
-        fun optimizeByteConversion(index0: Int, ins0: Instruction, index1: Int, ins1: Instruction) {
-            when (ins1.opcode) {
-                Opcode.CAST_B_TO_UB, Opcode.CAST_UB_TO_B,
-                Opcode.CAST_W_TO_B, Opcode.CAST_W_TO_UB,
-                Opcode.CAST_UW_TO_B, Opcode.CAST_UW_TO_UB -> instructionsToReplace[index1] = Instruction(Opcode.NOP)
-                Opcode.MSB -> throw CompilerException("msb of a byte")
-                Opcode.CAST_UB_TO_UW -> {
-                    val ins = Instruction(Opcode.PUSH_WORD, RuntimeValue(DataType.UWORD, ins0.arg!!.integerValue()))
-                    instructionsToReplace[index0] = ins
-                    instructionsToReplace[index1] = Instruction(Opcode.NOP)
-                }
-                Opcode.CAST_B_TO_W -> {
-                    val ins = Instruction(Opcode.PUSH_WORD, RuntimeValue(DataType.WORD, ins0.arg!!.integerValue()))
-                    instructionsToReplace[index0] = ins
-                    instructionsToReplace[index1] = Instruction(Opcode.NOP)
-                }
-                Opcode.CAST_B_TO_UW -> {
-                    val ins = Instruction(Opcode.PUSH_WORD, ins0.arg!!.cast(DataType.UWORD))
-                    instructionsToReplace[index0] = ins
-                    instructionsToReplace[index1] = Instruction(Opcode.NOP)
-                }
-                Opcode.CAST_UB_TO_W -> {
-                    val ins = Instruction(Opcode.PUSH_WORD, ins0.arg!!.cast(DataType.WORD))
-                    instructionsToReplace[index0] = ins
-                    instructionsToReplace[index1] = Instruction(Opcode.NOP)
-                }
-                Opcode.CAST_B_TO_F, Opcode.CAST_UB_TO_F -> {
-                    val ins = Instruction(Opcode.PUSH_FLOAT, RuntimeValue(DataType.FLOAT, ins0.arg!!.integerValue().toDouble()))
-                    instructionsToReplace[index0] = ins
-                    instructionsToReplace[index1] = Instruction(Opcode.NOP)
-                }
-                Opcode.CAST_W_TO_F, Opcode.CAST_UW_TO_F -> throw CompilerException("invalid conversion following a byte")
-                Opcode.DISCARD_BYTE -> {
-                    instructionsToReplace[index0] = Instruction(Opcode.NOP)
-                    instructionsToReplace[index1] = Instruction(Opcode.NOP)
-                }
-                Opcode.DISCARD_WORD, Opcode.DISCARD_FLOAT -> throw CompilerException("invalid discard type following a byte")
-                Opcode.MKWORD -> {}
-                else -> throw CompilerException("invalid conversion opcode ${ins1.opcode}")
-            }
-        }
-
-        for(blk in blocks) {
-            instructionsToReplace.clear()
-
-            val typeConversionOpcodes = setOf(
-                    Opcode.MSB,
-                    Opcode.MKWORD,
-                    Opcode.CAST_UB_TO_B,
-                    Opcode.CAST_UB_TO_UW,
-                    Opcode.CAST_UB_TO_W,
-                    Opcode.CAST_UB_TO_F,
-                    Opcode.CAST_B_TO_UB,
-                    Opcode.CAST_B_TO_UW,
-                    Opcode.CAST_B_TO_W,
-                    Opcode.CAST_B_TO_F,
-                    Opcode.CAST_UW_TO_UB,
-                    Opcode.CAST_UW_TO_B,
-                    Opcode.CAST_UW_TO_W,
-                    Opcode.CAST_UW_TO_F,
-                    Opcode.CAST_W_TO_UB,
-                    Opcode.CAST_W_TO_B,
-                    Opcode.CAST_W_TO_UW,
-                    Opcode.CAST_W_TO_F,
-                    Opcode.CAST_F_TO_UB,
-                    Opcode.CAST_F_TO_B,
-                    Opcode.CAST_F_TO_UW,
-                    Opcode.CAST_F_TO_W,
-                    Opcode.DISCARD_BYTE,
-                    Opcode.DISCARD_WORD,
-                    Opcode.DISCARD_FLOAT
-            )
-            blk.instructions.asSequence().withIndex().windowed(2).toList().forEach {
-                if (it[1].value.opcode in typeConversionOpcodes) {
-                    when (it[0].value.opcode) {
-                        Opcode.PUSH_BYTE -> optimizeByteConversion(it[0].index, it[0].value, it[1].index, it[1].value)
-                        Opcode.PUSH_WORD -> optimizeWordConversion(it[0].index, it[0].value, it[1].index, it[1].value)
-                        Opcode.PUSH_FLOAT -> optimizeFloatConversion(it[0].index, it[1].index, it[1].value)
-                        Opcode.PUSH_VAR_FLOAT,
-                        Opcode.PUSH_VAR_WORD,
-                        Opcode.PUSH_VAR_BYTE,
-                        Opcode.PUSH_MEM_B, Opcode.PUSH_MEM_UB,
-                        Opcode.PUSH_MEM_W, Opcode.PUSH_MEM_UW,
-                        Opcode.PUSH_MEM_FLOAT -> optimizeDiscardAfterPush(it[0].index, it[1].index, it[1].value)
-                        else -> {
-                        }
-                    }
-                }
-            }
-
-            for (rins in instructionsToReplace) {
-                blk.instructions[rins.key] = rins.value
-            }
-        }
-    }
-
-    fun variable(scopedname: String, decl: VarDecl) {
-        when(decl.type) {
-            VarDeclType.VAR -> {
-                // var decls that are defined inside of a StructDecl are skipped in the output
-                //   because every occurrence of the members will have a separate mangled vardecl for that occurrence
-                if(decl.parent is StructDecl)
-                    return
-
-                val valueparams = VariableParameters(decl.zeropage, decl.struct)
-                val value = when(decl.datatype) {
-                    in NumericDatatypes -> {
-                        RuntimeValue(decl.datatype, (decl.value as NumericLiteralValue).number)
-                    }
-                    in StringDatatypes -> {
-                        val litval = (decl.value as ReferenceLiteralValue)
-                        if(litval.heapId==null)
-                            throw CompilerException("string should already be in the heap")
-                        RuntimeValue(decl.datatype, heapId = litval.heapId)
-                    }
-                    in ArrayDatatypes -> {
-                        val litval = (decl.value as? ReferenceLiteralValue)
-                        if(litval!=null && litval.heapId==null)
-                            throw CompilerException("array should already be in the heap")
-                        if(litval!=null){
-                            RuntimeValue(decl.datatype, heapId = litval.heapId)
-                        } else {
-                            throw CompilerException("initialization value expected")
-                        }
-                    }
-                    DataType.STRUCT -> {
-                        // struct variables have been flattened already
-                        return
-                    }
-                    else -> throw CompilerException("weird datatype")
-                }
-                currentBlock.variables.add(Variable(scopedname, value, valueparams))
-            }
-            VarDeclType.MEMORY -> {
-                // note that constants are all folded away, but assembly code may still refer to them
-                val lv = decl.value as NumericLiteralValue
-                if(lv.type!= DataType.UWORD && lv.type!= DataType.UBYTE)
-                    throw CompilerException("expected integer memory address $lv")
-                currentBlock.memoryPointers[scopedname] = Pair(lv.number.toInt(), decl.datatype)
-            }
-            VarDeclType.CONST -> {
-                // note that constants are all folded away, but assembly code may still refer to them (if their integers)
-                // floating point constants are not generated at all!!
-                val lv = decl.value as NumericLiteralValue
-                if(lv.type in IntegerDatatypes)
-                    currentBlock.memoryPointers[scopedname] = Pair(lv.number.toInt(), decl.datatype)
-            }
-        }
-    }
-
-    fun instr(opcode: Opcode, arg: RuntimeValue? = null, arg2: RuntimeValue? = null, callLabel: String? = null, callLabel2: String? = null) {
-        currentBlock.instructions.add(Instruction(opcode, arg, arg2, callLabel, callLabel2))
-    }
-
-    fun label(labelname: String, asmProc: Boolean=false) {
-        val instr = LabelInstr(labelname, asmProc)
-        currentBlock.instructions.add(instr)
-        currentBlock.labels[labelname] = instr
-    }
-
-    fun line(position: Position) {
-        currentBlock.instructions.add(Instruction(Opcode.LINE, callLabel = "${position.line} ${position.file}"))
-    }
-
-    fun removeLastInstruction() {
-        currentBlock.instructions.removeAt(currentBlock.instructions.lastIndex)
-    }
-
-    fun memoryPointer(name: String, address: Int, datatype: DataType) {
-        currentBlock.memoryPointers[name] = Pair(address, datatype)
-    }
-
-    fun newBlock(name: String, address: Int?, options: Set<String>) {
-        currentBlock = ProgramBlock(name, address, force_output = "force_output" in options)
-        blocks.add(currentBlock)
-    }
-
-    fun writeCode(out: PrintStream, embeddedLabels: Boolean=true) {
-        out.println("; stackVM program code for '$name'")
-        writeMemory(out)
-        writeHeap(out)
-        for(blk in blocks) {
-            writeBlock(out, blk, embeddedLabels)
-        }
-    }
-
-    private fun writeHeap(out: PrintStream) {
-        out.println("%heap")
-        heap.allEntries().forEach {
-            out.print("${it.key}  ${it.value.type.name.toLowerCase()}  ")
-            when {
-                it.value.str!=null ->
-                    out.println("\"${escape(it.value.str!!)}\"")
-                it.value.array!=null -> {
-                    // this array can contain both normal integers, and pointer values
-                    val arrayvalues = it.value.array!!.map { av ->
-                        when {
-                            av.integer!=null -> av.integer.toString()
-                            av.addressOf!=null -> {
-                                if(av.addressOf.scopedname==null)
-                                    throw CompilerException("AddressOf scopedname should have been set")
-                                else
-                                    "&${av.addressOf.scopedname}"
-                            }
-                            else -> throw CompilerException("weird array value")
-                        }
-                    }
-                    out.println(arrayvalues)
-                }
-                it.value.doubleArray!=null ->
-                    out.println(it.value.doubleArray!!.toList())
-                else -> throw CompilerException("invalid heap entry $it")
-            }
-        }
-        out.println("%end_heap")
-    }
-
-    private fun writeBlock(out: PrintStream, blk: ProgramBlock, embeddedLabels: Boolean) {
-        out.println("\n%block ${blk.name} ${blk.address?.toString(16) ?: ""}")
-
-        out.println("%variables")
-        for (variable in blk.variables) {
-            if(variable.params.zp==ZeropageWish.REQUIRE_ZEROPAGE)
-                throw CompilerException("zp conflict")
-            val valuestr = variable.value.toString()
-            val struct =  if(variable.params.memberOfStruct==null) "" else "struct=${variable.params.memberOfStruct.name}"
-            out.println("${variable.scopedname}  ${variable.value.type.name.toLowerCase()}  $valuestr  zp=${variable.params.zp} s=$struct")
-        }
-        out.println("%end_variables")
-        out.println("%memorypointers")
-        for (iconst in blk.memoryPointers) {
-            out.println("${iconst.key}  ${iconst.value.second.name.toLowerCase()}  uw:${iconst.value.first.toString(16)}")
-        }
-        out.println("%end_memorypointers")
-        out.println("%instructions")
-        val labels = blk.labels.entries.associateBy({ it.value }) { it.key }
-        for (instr in blk.instructions) {
-            if (!embeddedLabels) {
-                val label = labels[instr]
-                if (label != null)
-                    out.println("$label:")
-            } else {
-                out.println(instr)
-            }
-        }
-        out.println("%end_instructions")
-
-        out.println("%end_block")
-    }
-
-    private fun writeMemory(out: PrintStream) {
-        out.println("%memory")
-        if (memory.isNotEmpty())
-            TODO("add support for writing/reading initial memory values")
-        out.println("%end_memory")
-    }
-}

DeprecatedStackVm/src/compiler/intermediate/Opcode.kt

@@ -1,291 +0,0 @@
-package compiler.intermediate
-
-enum class Opcode {
-
-    // pushing values on the (evaluation) stack
-    PUSH_BYTE,       // push byte value
-    PUSH_WORD,       // push word value   (or 'address' of string / array)
-    PUSH_FLOAT,      // push float value
-    PUSH_MEM_B,      // push byte value from memory to stack
-    PUSH_MEM_UB,     // push unsigned byte value from memory to stack
-    PUSH_MEM_W,      // push word value from memory to stack
-    PUSH_MEM_UW,     // push unsigned word value from memory to stack
-    PUSH_MEM_FLOAT,  // push float value from memory to stack
-    PUSH_MEMREAD,    // push memory value from address that's on the stack
-    PUSH_VAR_BYTE,   // push byte variable (ubyte, byte)
-    PUSH_VAR_WORD,   // push word variable (uword, word)
-    PUSH_VAR_FLOAT,  // push float variable
-    PUSH_REGAX_WORD, // push registers A/X as a 16-bit word
-    PUSH_REGAY_WORD, // push registers A/Y as a 16-bit word
-    PUSH_REGXY_WORD, // push registers X/Y as a 16-bit word
-    PUSH_ADDR_HEAPVAR,  // push the address of the variable that's on the heap (string or array)
-    DUP_B,          // duplicate the top byte on the stack
-    DUP_W,          // duplicate the top word on the stack
-
-    // popping values off the (evaluation) stack, possibly storing them in another location
-    DISCARD_BYTE,    // discard top byte value
-    DISCARD_WORD,    // discard top word value
-    DISCARD_FLOAT,   // discard top float value
-    POP_MEM_BYTE,    // pop (u)byte value into destination memory address
-    POP_MEM_WORD,    // pop (u)word value into destination memory address
-    POP_MEM_FLOAT,   // pop float value into destination memory address
-    POP_MEMWRITE,    // pop address and byte stack and write the byte to the memory address
-    POP_VAR_BYTE,    // pop (u)byte value into variable
-    POP_VAR_WORD,    // pop (u)word value into variable
-    POP_VAR_FLOAT,   // pop float value into variable
-    POP_REGAX_WORD,  // pop uword from stack into A/X registers
-    POP_REGAY_WORD,  // pop uword from stack into A/Y registers
-    POP_REGXY_WORD,  // pop uword from stack into X/Y registers
-
-    // numeric arithmetic
-    ADD_UB,
-    ADD_B,
-    ADD_UW,
-    ADD_W,
-    ADD_F,
-    SUB_UB,
-    SUB_B,
-    SUB_UW,
-    SUB_W,
-    SUB_F,
-    MUL_UB,
-    MUL_B,
-    MUL_UW,
-    MUL_W,
-    MUL_F,
-    IDIV_UB,
-    IDIV_B,
-    IDIV_UW,
-    IDIV_W,
-    DIV_F,
-    REMAINDER_UB,   // signed remainder is undefined/unimplemented
-    REMAINDER_UW,   // signed remainder is undefined/unimplemented
-    POW_F,
-    NEG_B,
-    NEG_W,
-    NEG_F,
-    ABS_B,
-    ABS_W,
-    ABS_F,
-
-    // bit shifts and bitwise arithmetic
-    SHIFTEDL_BYTE,      // shifts stack value rather than in-place mem/var
-    SHIFTEDL_WORD,      // shifts stack value rather than in-place mem/var
-    SHIFTEDR_UBYTE,     // shifts stack value rather than in-place mem/var
-    SHIFTEDR_SBYTE,     // shifts stack value rather than in-place mem/var
-    SHIFTEDR_UWORD,     // shifts stack value rather than in-place mem/var
-    SHIFTEDR_SWORD,     // shifts stack value rather than in-place mem/var
-    SHL_BYTE,
-    SHL_WORD,
-    SHL_MEM_BYTE,
-    SHL_MEM_WORD,
-    SHL_VAR_BYTE,
-    SHL_VAR_WORD,
-    SHR_UBYTE,
-    SHR_SBYTE,
-    SHR_UWORD,
-    SHR_SWORD,
-    SHR_MEM_UBYTE,
-    SHR_MEM_SBYTE,
-    SHR_MEM_UWORD,
-    SHR_MEM_SWORD,
-    SHR_VAR_UBYTE,
-    SHR_VAR_SBYTE,
-    SHR_VAR_UWORD,
-    SHR_VAR_SWORD,
-    ROL_BYTE,
-    ROL_WORD,
-    ROL_MEM_BYTE,
-    ROL_MEM_WORD,
-    ROL_VAR_BYTE,
-    ROL_VAR_WORD,
-    ROR_BYTE,
-    ROR_WORD,
-    ROR_MEM_BYTE,
-    ROR_MEM_WORD,
-    ROR_VAR_BYTE,
-    ROR_VAR_WORD,
-    ROL2_BYTE,
-    ROL2_WORD,
-    ROL2_MEM_BYTE,
-    ROL2_MEM_WORD,
-    ROL2_VAR_BYTE,
-    ROL2_VAR_WORD,
-    ROR2_BYTE,
-    ROR2_WORD,
-    ROR2_MEM_BYTE,
-    ROR2_MEM_WORD,
-    ROR2_VAR_BYTE,
-    ROR2_VAR_WORD,
-    BITAND_BYTE,
-    BITAND_WORD,
-    BITOR_BYTE,
-    BITOR_WORD,
-    BITXOR_BYTE,
-    BITXOR_WORD,
-    INV_BYTE,
-    INV_WORD,
-
-    // numeric type conversions
-    MSB,        // note: lsb is equivalent to  CAST_UW_TO_UB  or CAST_W_TO_UB
-    MKWORD,        // create a word from lsb + msb
-    CAST_UB_TO_B,
-    CAST_UB_TO_UW,
-    CAST_UB_TO_W,
-    CAST_UB_TO_F,
-    CAST_B_TO_UB,
-    CAST_B_TO_UW,
-    CAST_B_TO_W,
-    CAST_B_TO_F,
-    CAST_W_TO_UB,
-    CAST_W_TO_B,
-    CAST_W_TO_UW,
-    CAST_W_TO_F,
-    CAST_UW_TO_UB,
-    CAST_UW_TO_B,
-    CAST_UW_TO_W,
-    CAST_UW_TO_F,
-    CAST_F_TO_UB,
-    CAST_F_TO_B,
-    CAST_F_TO_UW,
-    CAST_F_TO_W,
-
-    // logical operations
-    AND_BYTE,
-    AND_WORD,
-    OR_BYTE,
-    OR_WORD,
-    XOR_BYTE,
-    XOR_WORD,
-    NOT_BYTE,
-    NOT_WORD,
-
-    // increment, decrement
-    INC_VAR_B,
-    INC_VAR_UB,
-    INC_VAR_W,
-    INC_VAR_UW,
-    INC_VAR_F,
-    DEC_VAR_B,
-    DEC_VAR_UB,
-    DEC_VAR_W,
-    DEC_VAR_UW,
-    DEC_VAR_F,
-    INC_MEMORY,             // increment direct address
-    DEC_MEMORY,             // decrement direct address
-    POP_INC_MEMORY,         // increment address from stack
-    POP_DEC_MEMORY,         // decrement address from address
-
-    // comparisons
-    LESS_B,
-    LESS_UB,
-    LESS_W,
-    LESS_UW,
-    LESS_F,
-    GREATER_B,
-    GREATER_UB,
-    GREATER_W,
-    GREATER_UW,
-    GREATER_F,
-    LESSEQ_B,
-    LESSEQ_UB,
-    LESSEQ_W,
-    LESSEQ_UW,
-    LESSEQ_F,
-    GREATEREQ_B,
-    GREATEREQ_UB,
-    GREATEREQ_W,
-    GREATEREQ_UW,
-    GREATEREQ_F,
-    EQUAL_BYTE,
-    EQUAL_WORD,
-    EQUAL_F,
-    NOTEQUAL_BYTE,
-    NOTEQUAL_WORD,
-    NOTEQUAL_F,
-    CMP_B,          // sets processor status flags based on comparison, instead of pushing a result value
-    CMP_UB,         // sets processor status flags based on comparison, instead of pushing a result value
-    CMP_W,          // sets processor status flags based on comparison, instead of pushing a result value
-    CMP_UW,         // sets processor status flags based on comparison, instead of pushing a result value
-
-    // array access and simple manipulations
-    READ_INDEXED_VAR_BYTE,
-    READ_INDEXED_VAR_WORD,
-    READ_INDEXED_VAR_FLOAT,
-    WRITE_INDEXED_VAR_BYTE,
-    WRITE_INDEXED_VAR_WORD,
-    WRITE_INDEXED_VAR_FLOAT,
-    INC_INDEXED_VAR_B,
-    INC_INDEXED_VAR_UB,
-    INC_INDEXED_VAR_W,
-    INC_INDEXED_VAR_UW,
-    INC_INDEXED_VAR_FLOAT,
-    DEC_INDEXED_VAR_B,
-    DEC_INDEXED_VAR_UB,
-    DEC_INDEXED_VAR_W,
-    DEC_INDEXED_VAR_UW,
-    DEC_INDEXED_VAR_FLOAT,
-
-    // branching, without consuming a value from the stack
-    JUMP,
-    BCS,       // branch if carry set
-    BCC,       // branch if carry clear
-    BZ,        // branch if zero flag
-    BNZ,       // branch if not zero flag
-    BNEG,      // branch if negative flag
-    BPOS,      // branch if not negative flag
-    BVS,       // branch if overflow flag
-    BVC,       // branch if not overflow flag
-    // branching, based on value on the stack (which is consumed)
-    JZ,         // branch if value is zero (byte)
-    JNZ,        // branch if value is not zero (byte)
-    JZW,         // branch if value is zero (word)
-    JNZW,        // branch if value is not zero (word)
-
-    // subroutines
-    CALL,
-    RETURN,
-    SYSCALL,
-    START_PROCDEF,
-    END_PROCDEF,
-
-    // misc
-    SEC,        // set carry status flag  NOTE: is mostly fake, carry flag is not affected by any numeric operations
-    CLC,        // clear carry status flag  NOTE: is mostly fake, carry flag is not affected by any numeric operations
-    SEI,        // set irq-disable status flag
-    CLI,        // clear irq-disable status flag
-    CARRY_TO_A, // load var/register A with carry status bit
-    RSAVE,      // save all internal registers and status flags
-    RSAVEX,     // save just X (the evaluation stack pointer)
-    RRESTORE,   // restore all internal registers and status flags
-    RRESTOREX,  // restore just X (the evaluation stack pointer)
-
-    NOP,        // do nothing
-    BREAKPOINT, // breakpoint
-    TERMINATE,  // end the program
-    LINE,       // track source file line number
-    INLINE_ASSEMBLY,        // container to hold inline raw assembly code
-    INCLUDE_FILE            // directive to include a file at this position in the memory of the program
-}
-
-val opcodesWithVarArgument = setOf(
-        Opcode.INC_VAR_B, Opcode.INC_VAR_W, Opcode.DEC_VAR_B, Opcode.DEC_VAR_W,
-        Opcode.INC_VAR_UB, Opcode.INC_VAR_UW, Opcode.DEC_VAR_UB, Opcode.DEC_VAR_UW,
-        Opcode.SHR_VAR_SBYTE, Opcode.SHR_VAR_UBYTE, Opcode.SHR_VAR_SWORD, Opcode.SHR_VAR_UWORD,
-        Opcode.SHL_VAR_BYTE, Opcode.SHL_VAR_WORD,
-        Opcode.ROL_VAR_BYTE, Opcode.ROL_VAR_WORD, Opcode.ROR_VAR_BYTE, Opcode.ROR_VAR_WORD,
-        Opcode.ROL2_VAR_BYTE, Opcode.ROL2_VAR_WORD, Opcode.ROR2_VAR_BYTE, Opcode.ROR2_VAR_WORD,
-        Opcode.POP_VAR_BYTE, Opcode.POP_VAR_WORD, Opcode.POP_VAR_FLOAT,
-        Opcode.PUSH_VAR_BYTE, Opcode.PUSH_VAR_WORD, Opcode.PUSH_VAR_FLOAT, Opcode.PUSH_ADDR_HEAPVAR,
-        Opcode.READ_INDEXED_VAR_BYTE, Opcode.READ_INDEXED_VAR_WORD, Opcode.READ_INDEXED_VAR_FLOAT,
-        Opcode.WRITE_INDEXED_VAR_BYTE, Opcode.WRITE_INDEXED_VAR_WORD, Opcode.WRITE_INDEXED_VAR_FLOAT,
-        Opcode.INC_INDEXED_VAR_UB, Opcode.INC_INDEXED_VAR_B, Opcode.INC_INDEXED_VAR_UW,
-        Opcode.INC_INDEXED_VAR_W, Opcode.INC_INDEXED_VAR_FLOAT,
-        Opcode.DEC_INDEXED_VAR_UB, Opcode.DEC_INDEXED_VAR_B, Opcode.DEC_INDEXED_VAR_UW,
-        Opcode.DEC_INDEXED_VAR_W, Opcode.DEC_INDEXED_VAR_FLOAT
-)
-
-val branchOpcodes = setOf(
-        Opcode.BCS, Opcode.BCC, Opcode.BZ, Opcode.BNZ,
-        Opcode.BNEG, Opcode.BPOS, Opcode.BVS, Opcode.BVC
-)

DeprecatedStackVm/src/compiler/target/c64/codegen/AsmGen.kt

@@ -1,761 +0,0 @@
-package compiler.target.c64.codegen
-
-// note: to put stuff on the stack, we use Absolute,X  addressing mode which is 3 bytes / 4 cycles
-// possible space optimization is to use zeropage (indirect),Y  which is 2 bytes, but 5 cycles
-
-import prog8.ast.antlr.escape
-import prog8.ast.base.DataType
-import prog8.ast.base.initvarsSubName
-import prog8.ast.statements.ZeropageWish
-import prog8.compiler.*
-import prog8.compiler.intermediate.Instruction
-import prog8.compiler.intermediate.IntermediateProgram
-import prog8.compiler.intermediate.LabelInstr
-import prog8.compiler.intermediate.Opcode
-import prog8.compiler.target.c64.AssemblyProgram
-import prog8.compiler.target.c64.MachineDefinition
-import prog8.compiler.target.c64.Petscii
-import prog8.vm.RuntimeValue
-import java.io.File
-import java.util.*
-import kotlin.math.abs
-
-
-class AssemblyError(msg: String) : RuntimeException(msg)
-
-
-
-internal fun intVal(valueInstr: Instruction) = valueInstr.arg!!.integerValue()
-internal fun hexVal(valueInstr: Instruction) = valueInstr.arg!!.integerValue().toHex()
-internal fun hexValPlusOne(valueInstr: Instruction) = (valueInstr.arg!!.integerValue()+1).toHex()
-internal fun getFloatConst(value: RuntimeValue): String =
-        globalFloatConsts[value.numericValue().toDouble()]
-                ?: throw AssemblyError("should have a global float const for number $value")
-
-internal val globalFloatConsts = mutableMapOf<Double, String>()
-
-internal fun signExtendA(into: String) =
-        """
-        ora  #$7f
-        bmi  +
-        lda  #0
-+       sta  $into
-        """
-
-class AsmGen(private val options: CompilationOptions, private val program: IntermediateProgram,
-             private val heap: HeapValues, private val zeropage: Zeropage) {
-    private val assemblyLines = mutableListOf<String>()
-    private lateinit var block: IntermediateProgram.ProgramBlock
-
-    init {
-        // Convert invalid label names (such as "<anon-1>") to something that's allowed.
-        val newblocks = mutableListOf<IntermediateProgram.ProgramBlock>()
-        for(block in program.blocks) {
-            val newvars = block.variables.map { IntermediateProgram.Variable(symname(it.scopedname, block), it.value, it.params) }.toMutableList()
-            val newlabels = block.labels.map { symname(it.key, block) to it.value}.toMap().toMutableMap()
-            val newinstructions = block.instructions.asSequence().map {
-                when {
-                    it is LabelInstr -> LabelInstr(symname(it.name, block), it.asmProc)
-                    it.opcode == Opcode.INLINE_ASSEMBLY -> it
-                    else ->
-                        Instruction(it.opcode, it.arg, it.arg2,
-                            callLabel = if (it.callLabel != null) symname(it.callLabel, block) else null,
-                            callLabel2 = if (it.callLabel2 != null) symname(it.callLabel2, block) else null)
-                }
-            }.toMutableList()
-            val newMempointers = block.memoryPointers.map { symname(it.key, block) to it.value }.toMap().toMutableMap()
-            val newblock = IntermediateProgram.ProgramBlock(
-                    block.name,
-                    block.address,
-                    newinstructions,
-                    newvars,
-                    newMempointers,
-                    newlabels,
-                    force_output = block.force_output)
-            newblocks.add(newblock)
-        }
-        program.blocks.clear()
-        program.blocks.addAll(newblocks)
-
-        val newAllocatedZp = program.allocatedZeropageVariables.map { symname(it.key, null) to it.value}
-        program.allocatedZeropageVariables.clear()
-        program.allocatedZeropageVariables.putAll(newAllocatedZp)
-
-        // make a list of all const floats that are used
-        for(block in program.blocks) {
-            for(ins in block.instructions.filter{it.arg?.type== DataType.FLOAT}) {
-                val float = ins.arg!!.numericValue().toDouble()
-                if(float !in globalFloatConsts)
-                    globalFloatConsts[float] = "prog8_const_float_${globalFloatConsts.size}"
-            }
-        }
-    }
-
-    fun compileToAssembly(optimize: Boolean): AssemblyProgram {
-        println("Generating assembly code from intermediate code... ")
-
-        assemblyLines.clear()
-        header()
-        for(b in program.blocks)
-            block2asm(b)
-
-        if(optimize) {
-            var optimizationsDone = 1
-            while (optimizationsDone > 0) {
-                optimizationsDone = optimizeAssembly(assemblyLines)
-            }
-        }
-
-        File("${program.name}.asm").printWriter().use {
-            for (line in assemblyLines) { it.println(line) }
-        }
-
-        return AssemblyProgram(program.name)
-    }
-
-    private fun out(str: String, splitlines: Boolean=true) {
-        if(splitlines) {
-            for (line in str.split('\n')) {
-                val trimmed = if (line.startsWith(' ')) "\t" + line.trim() else line.trim()
-                // trimmed = trimmed.replace(Regex("^\\+\\s+"), "+\t")  // sanitize local label indentation
-                assemblyLines.add(trimmed)
-            }
-        } else assemblyLines.add(str)
-    }
-
-
-    // convert a fully scoped name (defined in the given block) to a valid assembly symbol name
-    private fun symname(scoped: String, block: IntermediateProgram.ProgramBlock?): String {
-        if(' ' in scoped)
-            return scoped
-        val blockLocal: Boolean
-        var name = if (block!=null && scoped.startsWith("${block.name}.")) {
-            blockLocal = true
-            scoped.substring(block.name.length+1)
-        }
-        else {
-            blockLocal = false
-            scoped
-        }
-        name = name.replace("<", "prog8_").replace(">", "")     // take care of the autogenerated invalid (anon) label names
-        if(name=="-")
-            return "-"
-        if(blockLocal)
-            name = name.replace(".", "_")
-        else {
-            val parts = name.split(".", limit=2)
-            if(parts.size>1)
-                name = "${parts[0]}.${parts[1].replace(".", "_")}"
-        }
-        return name.replace("-", "")
-    }
-
-    private fun makeFloatFill(flt: MachineDefinition.Mflpt5): String {
-        val b0 = "$"+flt.b0.toString(16).padStart(2, '0')
-        val b1 = "$"+flt.b1.toString(16).padStart(2, '0')
-        val b2 = "$"+flt.b2.toString(16).padStart(2, '0')
-        val b3 = "$"+flt.b3.toString(16).padStart(2, '0')
-        val b4 = "$"+flt.b4.toString(16).padStart(2, '0')
-        return "$b0, $b1, $b2, $b3, $b4"
-    }
-
-    private fun header() {
-        val ourName = this.javaClass.name
-        out("; 6502 assembly code for '${program.name}'")
-        out("; generated by $ourName on ${Date()}")
-        out("; assembler syntax is for the 64tasm cross-assembler")
-        out("; output options: output=${options.output} launcher=${options.launcher} zp=${options.zeropage}")
-        out("\n.cpu  '6502'\n.enc  'none'\n")
-
-        if(program.loadAddress==0)   // fix load address
-            program.loadAddress = if(options.launcher==LauncherType.BASIC)
-                MachineDefinition.BASIC_LOAD_ADDRESS else MachineDefinition.RAW_LOAD_ADDRESS
-
-        when {
-            options.launcher == LauncherType.BASIC -> {
-                if (program.loadAddress != 0x0801)
-                    throw AssemblyError("BASIC output must have load address $0801")
-                out("; ---- basic program with sys call ----")
-                out("* = ${program.loadAddress.toHex()}")
-                val year = Calendar.getInstance().get(Calendar.YEAR)
-                out("  .word  (+), $year")
-                out("  .null  $9e, format(' %d ', _prog8_entrypoint), $3a, $8f, ' prog8 by idj'")
-                out("+\t.word  0")
-                out("_prog8_entrypoint\t; assembly code starts here\n")
-                out("  jsr  prog8_lib.init_system")
-            }
-            options.output == OutputType.PRG -> {
-                out("; ---- program without basic sys call ----")
-                out("* = ${program.loadAddress.toHex()}\n")
-                out("  jsr  prog8_lib.init_system")
-            }
-            options.output == OutputType.RAW -> {
-                out("; ---- raw assembler program ----")
-                out("* = ${program.loadAddress.toHex()}\n")
-            }
-        }
-
-        if(zeropage.exitProgramStrategy!=Zeropage.ExitProgramStrategy.CLEAN_EXIT) {
-            // disable shift-commodore charset switching and run/stop key
-            out("  lda  #$80")
-            out("  lda  #$80")
-            out("  sta  657\t; disable charset switching")
-            out("  lda  #239")
-            out("  sta  808\t; disable run/stop key")
-        }
-
-        out("  ldx  #\$ff\t; init estack pointer")
-        out("  ; initialize the variables in each block")
-        for(block in program.blocks) {
-            val initVarsLabel = block.instructions.firstOrNull { it is LabelInstr && it.name== initvarsSubName } as? LabelInstr
-            if(initVarsLabel!=null)
-                out("  jsr  ${block.name}.${initVarsLabel.name}")
-        }
-        out("  clc")
-        when(zeropage.exitProgramStrategy) {
-            Zeropage.ExitProgramStrategy.CLEAN_EXIT -> {
-                out("  jmp  main.start\t; jump to program entrypoint")
-            }
-            Zeropage.ExitProgramStrategy.SYSTEM_RESET -> {
-                out("  jsr  main.start\t; call program entrypoint")
-                out("  jmp  (c64.RESET_VEC)\t; cold reset")
-            }
-        }
-        out("")
-
-        // the global list of all floating point constants for the whole program
-        for(flt in globalFloatConsts) {
-            val floatFill = makeFloatFill(MachineDefinition.Mflpt5.fromNumber(flt.key))
-            out("${flt.value}\t.byte  $floatFill  ; float ${flt.key}")
-        }
-    }
-
-    private fun block2asm(blk: IntermediateProgram.ProgramBlock) {
-        block = blk
-        out("\n; ---- block: '${block.name}' ----")
-        if(!blk.force_output)
-            out("${block.name}\t.proc\n")
-        if(block.address!=null) {
-            out(".cerror * > ${block.address?.toHex()}, 'block address overlaps by ', *-${block.address?.toHex()},' bytes'")
-            out("* = ${block.address?.toHex()}")
-        }
-
-        // deal with zeropage variables
-        for(variable in blk.variables) {
-            val sym = symname(blk.name+"."+variable.scopedname, null)
-            val zpVar = program.allocatedZeropageVariables[sym]
-            if(zpVar==null) {
-                // This var is not on the ZP yet. Attempt to move it there (if it's not a float, those take up too much space)
-                if(variable.params.zp != ZeropageWish.NOT_IN_ZEROPAGE &&
-                        variable.value.type in zeropage.allowedDatatypes
-                        && variable.value.type != DataType.FLOAT) {
-                    try {
-                        val address = zeropage.allocate(sym, variable.value.type, null)
-                        out("${variable.scopedname} = $address\t; auto zp ${variable.value.type}")
-                        // make sure we add the var to the set of zpvars for this block
-                        program.allocatedZeropageVariables[sym] = Pair(address, variable.value.type)
-                    } catch (x: ZeropageDepletedError) {
-                        // leave it as it is.
-                    }
-                }
-            }
-            else {
-                // it was already allocated on the zp
-                out("${variable.scopedname} = ${zpVar.first}\t; zp ${zpVar.second}")
-            }
-        }
-
-        out("\n; memdefs and kernel subroutines")
-        memdefs2asm(block)
-        out("\n; non-zeropage variables")
-        vardecls2asm(block)
-        out("")
-
-        val instructionPatternWindowSize = 8        // increase once patterns occur longer than this.
-        var processed = 0
-
-        for (ins in block.instructions.windowed(instructionPatternWindowSize, partialWindows = true)) {
-            if (processed == 0) {
-                processed = instr2asm(ins)
-                if (processed == 0) {
-                    // the instructions are not recognised yet and can't be translated into assembly
-                    throw CompilerException("no asm translation found for instruction pattern: $ins")
-                }
-            }
-            processed--
-        }
-        if(!blk.force_output)
-            out("\n\t.pend\n")
-    }
-
-    private fun memdefs2asm(block: IntermediateProgram.ProgramBlock) {
-        for(m in block.memoryPointers) {
-            out("  ${m.key} = ${m.value.first.toHex()}")
-        }
-    }
-
-    private fun vardecls2asm(block: IntermediateProgram.ProgramBlock) {
-        val uniqueNames = block.variables.map { it.scopedname }.toSet()
-        if (uniqueNames.size != block.variables.size)
-            throw AssemblyError("not all variables have unique names")
-
-        // these are the non-zeropage variables.
-        // first get all the flattened struct members, they MUST remain in order
-        out(";  flattened struct members")
-        val (structMembers, normalVars) = block.variables.partition { it.params.memberOfStruct!=null }
-        structMembers.forEach { vardecl2asm(it.scopedname, it.value, it.params) }
-
-        // sort the other variables by type
-        out(";  other variables sorted by type")
-        val sortedVars = normalVars.sortedBy { it.value.type }
-        for (variable in sortedVars) {
-            val sym = symname(block.name + "." + variable.scopedname, null)
-            if(sym in program.allocatedZeropageVariables)
-                continue  // skip the ones that already belong in the zero page
-            vardecl2asm(variable.scopedname, variable.value, variable.params)
-        }
-    }
-
-    private fun vardecl2asm(varname: String, value: RuntimeValue, parameters: IntermediateProgram.VariableParameters) {
-        when (value.type) {
-            DataType.UBYTE -> out("$varname\t.byte  0")
-            DataType.BYTE -> out("$varname\t.char  0")
-            DataType.UWORD -> out("$varname\t.word  0")
-            DataType.WORD -> out("$varname\t.sint  0")
-            DataType.FLOAT -> out("$varname\t.byte  0,0,0,0,0  ; float")
-            DataType.STR, DataType.STR_S -> {
-                val rawStr = heap.get(value.heapId!!).str!!
-                val bytes = encodeStr(rawStr, value.type).map { "$" + it.toString(16).padStart(2, '0') }
-                out("$varname\t; ${value.type} \"${escape(rawStr).replace("\u0000", "<NULL>")}\"")
-                for (chunk in bytes.chunked(16))
-                    out("  .byte  " + chunk.joinToString())
-            }
-            DataType.ARRAY_UB -> {
-                // unsigned integer byte arraysize
-                val data = makeArrayFillDataUnsigned(value)
-                if (data.size <= 16)
-                    out("$varname\t.byte  ${data.joinToString()}")
-                else {
-                    out(varname)
-                    for (chunk in data.chunked(16))
-                        out("  .byte  " + chunk.joinToString())
-                }
-            }
-            DataType.ARRAY_B -> {
-                // signed integer byte arraysize
-                val data = makeArrayFillDataSigned(value)
-                if (data.size <= 16)
-                    out("$varname\t.char  ${data.joinToString()}")
-                else {
-                    out(varname)
-                    for (chunk in data.chunked(16))
-                        out("  .char  " + chunk.joinToString())
-                }
-            }
-            DataType.ARRAY_UW -> {
-                // unsigned word arraysize
-                val data = makeArrayFillDataUnsigned(value)
-                if (data.size <= 16)
-                    out("$varname\t.word  ${data.joinToString()}")
-                else {
-                    out(varname)
-                    for (chunk in data.chunked(16))
-                        out("  .word  " + chunk.joinToString())
-                }
-            }
-            DataType.ARRAY_W -> {
-                // signed word arraysize
-                val data = makeArrayFillDataSigned(value)
-                if (data.size <= 16)
-                    out("$varname\t.sint  ${data.joinToString()}")
-                else {
-                    out(varname)
-                    for (chunk in data.chunked(16))
-                        out("  .sint  " + chunk.joinToString())
-                }
-            }
-            DataType.ARRAY_F -> {
-                // float arraysize
-                val array = heap.get(value.heapId!!).doubleArray!!
-                val floatFills = array.map { makeFloatFill(MachineDefinition.Mflpt5.fromNumber(it)) }
-                out(varname)
-                for (f in array.zip(floatFills))
-                    out("  .byte  ${f.second}  ; float ${f.first}")
-            }
-            DataType.STRUCT -> throw AssemblyError("vars of type STRUCT should have been removed because flattened")
-        }
-    }
-
-
-    private fun encodeStr(str: String, dt: DataType): List<Short> {
-        return when(dt) {
-            DataType.STR -> {
-                val bytes = Petscii.encodePetscii(str, true)
-                bytes.plus(0)
-            }
-            DataType.STR_S -> {
-                val bytes = Petscii.encodeScreencode(str, true)
-                bytes.plus(0)
-            }
-            else -> throw AssemblyError("invalid str type")
-        }
-    }
-
-    private fun makeArrayFillDataUnsigned(value: RuntimeValue): List<String> {
-        val array = heap.get(value.heapId!!).array!!
-        return when {
-            value.type== DataType.ARRAY_UB ->
-                // byte array can never contain pointer-to types, so treat values as all integers
-                array.map { "$"+it.integer!!.toString(16).padStart(2, '0') }
-            value.type== DataType.ARRAY_UW -> array.map {
-                when {
-                    it.integer!=null -> "$"+it.integer.toString(16).padStart(2, '0')
-                    it.addressOf!=null -> symname(it.addressOf.scopedname!!, block)
-                    else -> throw AssemblyError("weird type in array")
-                }
-            }
-            else -> throw AssemblyError("invalid arraysize type")
-        }
-    }
-
-    private fun makeArrayFillDataSigned(value: RuntimeValue): List<String> {
-        val array = heap.get(value.heapId!!).array!!
-        // note: array of signed value can never contain pointer-to type, so simply accept values as being all integers
-        return if (value.type == DataType.ARRAY_B || value.type == DataType.ARRAY_W) {
-            array.map {
-                if(it.integer!!>=0)
-                    "$"+it.integer.toString(16).padStart(2, '0')
-                else
-                    "-$"+abs(it.integer).toString(16).padStart(2, '0')
-            }
-        }
-        else throw AssemblyError("invalid arraysize type")
-    }
-
-    private fun instr2asm(ins: List<Instruction>): Int {
-        // find best patterns (matching the most of the lines, then with the smallest weight)
-        val fragments = findPatterns(ins).sortedByDescending { it.segmentSize }
-        if(fragments.isEmpty()) {
-            // we didn't find any matching patterns (complex multi-instruction fragments), try simple ones
-            val firstIns = ins[0]
-            val singleAsm = simpleInstr2Asm(firstIns, block)
-            if(singleAsm != null) {
-                outputAsmFragment(singleAsm)
-                return 1
-            }
-            return 0
-        }
-        val best = fragments[0]
-        outputAsmFragment(best.asm)
-        return best.segmentSize
-    }
-
-    private fun outputAsmFragment(singleAsm: String) {
-        if (singleAsm.isNotEmpty()) {
-            if(singleAsm.startsWith("@inline@"))
-                out(singleAsm.substring(8), false)
-            else {
-                val withNewlines = singleAsm.replace('|', '\n')
-                out(withNewlines)
-            }
-        }
-    }
-
-    private fun findPatterns(segment: List<Instruction>): List<AsmFragment> {
-        val opcodes = segment.map { it.opcode }
-        val result = mutableListOf<AsmFragment>()
-
-        // check for operations that modify a single value, by putting it on the stack (and popping it afterwards)
-        if((opcodes[0]==Opcode.PUSH_VAR_BYTE && opcodes[2]==Opcode.POP_VAR_BYTE) ||
-                (opcodes[0]==Opcode.PUSH_VAR_WORD && opcodes[2]==Opcode.POP_VAR_WORD) ||
-                (opcodes[0]==Opcode.PUSH_VAR_FLOAT && opcodes[2]==Opcode.POP_VAR_FLOAT)) {
-            if (segment[0].callLabel == segment[2].callLabel) {
-                val fragment = sameVarOperation(segment[0].callLabel!!, segment[1])
-                if (fragment != null) {
-                    fragment.segmentSize = 3
-                    result.add(fragment)
-                }
-            }
-        }
-        else if((opcodes[0]==Opcode.PUSH_BYTE && opcodes[1] in setOf(Opcode.INC_INDEXED_VAR_B, Opcode.INC_INDEXED_VAR_UB,
-                        Opcode.INC_INDEXED_VAR_UW, Opcode.INC_INDEXED_VAR_W, Opcode.INC_INDEXED_VAR_FLOAT,
-                        Opcode.DEC_INDEXED_VAR_B, Opcode.DEC_INDEXED_VAR_UB, Opcode.DEC_INDEXED_VAR_W,
-                        Opcode.DEC_INDEXED_VAR_UW, Opcode.DEC_INDEXED_VAR_FLOAT))) {
-            val fragment = sameConstantIndexedVarOperation(segment[1].callLabel!!, segment[0].arg!!.integerValue(), segment[1])
-            if(fragment!=null) {
-                fragment.segmentSize=2
-                result.add(fragment)
-            }
-        }
-        else if((opcodes[0]==Opcode.PUSH_VAR_BYTE && opcodes[1] in setOf(Opcode.INC_INDEXED_VAR_B, Opcode.INC_INDEXED_VAR_UB,
-                        Opcode.INC_INDEXED_VAR_UW, Opcode.INC_INDEXED_VAR_W, Opcode.INC_INDEXED_VAR_FLOAT,
-                        Opcode.DEC_INDEXED_VAR_B, Opcode.DEC_INDEXED_VAR_UB, Opcode.DEC_INDEXED_VAR_W,
-                        Opcode.DEC_INDEXED_VAR_UW, Opcode.DEC_INDEXED_VAR_FLOAT))) {
-            val fragment = sameIndexedVarOperation(segment[1].callLabel!!, segment[0].callLabel!!, segment[1])
-            if(fragment!=null) {
-                fragment.segmentSize=2
-                result.add(fragment)
-            }
-        }
-        else if((opcodes[0]==Opcode.PUSH_MEM_UB && opcodes[2]==Opcode.POP_MEM_BYTE) ||
-                (opcodes[0]==Opcode.PUSH_MEM_B && opcodes[2]==Opcode.POP_MEM_BYTE) ||
-                (opcodes[0]==Opcode.PUSH_MEM_UW && opcodes[2]==Opcode.POP_MEM_WORD) ||
-                (opcodes[0]==Opcode.PUSH_MEM_W && opcodes[2]==Opcode.POP_MEM_WORD) ||
-                (opcodes[0]==Opcode.PUSH_MEM_FLOAT && opcodes[2]==Opcode.POP_MEM_FLOAT)) {
-            if(segment[0].arg==segment[2].arg) {
-                val fragment = sameMemOperation(segment[0].arg!!.integerValue(), segment[1])
-                if(fragment!=null) {
-                    fragment.segmentSize = 3
-                    result.add(fragment)
-                }
-            }
-        }
-        else if((opcodes[0]==Opcode.PUSH_BYTE && opcodes[1]==Opcode.READ_INDEXED_VAR_BYTE &&
-                        opcodes[3]==Opcode.PUSH_BYTE && opcodes[4]==Opcode.WRITE_INDEXED_VAR_BYTE) ||
-                (opcodes[0]==Opcode.PUSH_BYTE && opcodes[1]==Opcode.READ_INDEXED_VAR_WORD &&
-                        opcodes[3]==Opcode.PUSH_BYTE && opcodes[4]==Opcode.WRITE_INDEXED_VAR_WORD)) {
-            if(segment[0].arg==segment[3].arg && segment[1].callLabel==segment[4].callLabel) {
-                val fragment = sameConstantIndexedVarOperation(segment[1].callLabel!!, segment[0].arg!!.integerValue(), segment[2])
-                if(fragment!=null){
-                    fragment.segmentSize = 5
-                    result.add(fragment)
-                }
-            }
-        }
-        else if((opcodes[0]==Opcode.PUSH_VAR_BYTE && opcodes[1]==Opcode.READ_INDEXED_VAR_BYTE &&
-                        opcodes[3]==Opcode.PUSH_VAR_BYTE && opcodes[4]==Opcode.WRITE_INDEXED_VAR_BYTE) ||
-                (opcodes[0]==Opcode.PUSH_VAR_BYTE && opcodes[1]==Opcode.READ_INDEXED_VAR_WORD &&
-                        opcodes[3]==Opcode.PUSH_VAR_BYTE && opcodes[4]==Opcode.WRITE_INDEXED_VAR_WORD)) {
-            if(segment[0].callLabel==segment[3].callLabel && segment[1].callLabel==segment[4].callLabel) {
-                val fragment = sameIndexedVarOperation(segment[1].callLabel!!, segment[0].callLabel!!, segment[2])
-                if(fragment!=null){
-                    fragment.segmentSize = 5
-                    result.add(fragment)
-                }
-            }
-        }
-
-        // add any matching patterns from the big list
-        for(pattern in Patterns.patterns) {
-            if(pattern.sequence.size > segment.size || (pattern.altSequence!=null && pattern.altSequence.size > segment.size))
-                continue        //  don't accept patterns that don't fit
-            val opcodesList = opcodes.subList(0, pattern.sequence.size)
-            if(pattern.sequence == opcodesList) {
-                val asm = pattern.asm(segment)
-                if(asm!=null)
-                    result.add(AsmFragment(asm, pattern.sequence.size))
-            } else if(pattern.altSequence!=null) {
-                val opcodesListAlt = opcodes.subList(0, pattern.altSequence.size)
-                if(pattern.altSequence == opcodesListAlt) {
-                    val asm = pattern.asm(segment)
-                    if (asm != null)
-                        result.add(AsmFragment(asm, pattern.sequence.size))
-                }
-            }
-        }
-
-        return result
-    }
-
-    private fun sameConstantIndexedVarOperation(variable: String, index: Int, ins: Instruction): AsmFragment? {
-        // an in place operation that consists of a push-value / op / push-index-value / pop-into-indexed-var
-        return when(ins.opcode) {
-            Opcode.SHL_BYTE -> AsmFragment(" asl  $variable+$index", 8)
-            Opcode.SHR_UBYTE -> AsmFragment(" lsr  $variable+$index", 8)
-            Opcode.SHR_SBYTE -> AsmFragment(" lda  $variable+$index |  asl  a |  ror  $variable+$index")
-            Opcode.SHL_WORD -> AsmFragment(" asl  $variable+${index * 2 + 1} |  rol  $variable+${index * 2}", 8)
-            Opcode.SHR_UWORD -> AsmFragment(" lsr  $variable+${index * 2 + 1} |  ror  $variable+${index * 2}", 8)
-            Opcode.SHR_SWORD -> AsmFragment(" lda  $variable+${index * 2 + 1} |  asl  a |  ror  $variable+${index * 2 + 1} |  ror  $variable+${index * 2}", 8)
-            Opcode.ROL_BYTE -> AsmFragment(" rol  $variable+$index", 8)
-            Opcode.ROR_BYTE -> AsmFragment(" ror  $variable+$index", 8)
-            Opcode.ROL_WORD -> AsmFragment(" rol  $variable+${index * 2 + 1} |  rol  $variable+${index * 2}", 8)
-            Opcode.ROR_WORD -> AsmFragment(" ror  $variable+${index * 2 + 1} |  ror  $variable+${index * 2}", 8)
-            Opcode.ROL2_BYTE -> AsmFragment(" lda  $variable+$index |  cmp  #\$80 |  rol  $variable+$index", 8)
-            Opcode.ROR2_BYTE -> AsmFragment(" lda  $variable+$index |  lsr  a |  bcc  + |  ora  #\$80 |+ |  sta  $variable+$index", 10)
-            Opcode.ROL2_WORD -> AsmFragment(" asl  $variable+${index * 2 + 1} |  rol  $variable+${index * 2} |  bcc  + |  inc  $variable+${index * 2 + 1} |+", 20)
-            Opcode.ROR2_WORD -> AsmFragment(" lsr  $variable+${index * 2 + 1} |  ror  $variable+${index * 2} |  bcc  + |  lda  $variable+${index * 2 + 1} |  ora  #\$80 |  sta  $variable+${index * 2 + 1} |+", 30)
-            Opcode.INC_INDEXED_VAR_B, Opcode.INC_INDEXED_VAR_UB -> AsmFragment(" inc  $variable+$index", 2)
-            Opcode.DEC_INDEXED_VAR_B, Opcode.DEC_INDEXED_VAR_UB -> AsmFragment(" dec  $variable+$index", 5)
-            Opcode.INC_INDEXED_VAR_W, Opcode.INC_INDEXED_VAR_UW -> AsmFragment(" inc  $variable+${index * 2} |  bne  + |  inc  $variable+${index * 2 + 1} |+")
-            Opcode.DEC_INDEXED_VAR_W, Opcode.DEC_INDEXED_VAR_UW -> AsmFragment(" lda  $variable+${index * 2} |  bne  + |  dec  $variable+${index * 2 + 1} |+ |  dec  $variable+${index * 2}")
-            Opcode.INC_INDEXED_VAR_FLOAT -> AsmFragment(
-                    """
-                lda  #<($variable+${index * MachineDefinition.Mflpt5.MemorySize})
-                ldy  #>($variable+${index * MachineDefinition.Mflpt5.MemorySize})
-                jsr  c64flt.inc_var_f
-                """)
-            Opcode.DEC_INDEXED_VAR_FLOAT -> AsmFragment(
-                    """
-                lda  #<($variable+${index * MachineDefinition.Mflpt5.MemorySize})
-                ldy  #>($variable+${index * MachineDefinition.Mflpt5.MemorySize})
-                jsr  c64flt.dec_var_f
-                """)
-
-            else -> null
-        }
-    }
-
-    private fun sameIndexedVarOperation(variable: String, indexVar: String, ins: Instruction): AsmFragment? {
-        // an in place operation that consists of a push-value / op / push-index-var / pop-into-indexed-var
-        val saveX = " stx  ${MachineDefinition.C64Zeropage.SCRATCH_B1} |"
-        val restoreX = " | ldx  ${MachineDefinition.C64Zeropage.SCRATCH_B1}"
-        val loadXWord: String
-        val loadX: String
-
-        when(indexVar) {
-            "X" -> {
-                loadX = ""
-                loadXWord = " txa |  asl  a |  tax |"
-            }
-            "Y" -> {
-                loadX = " tya |  tax |"
-                loadXWord = " tya |  asl  a |  tax |"
-            }
-            "A" -> {
-                loadX = " tax |"
-                loadXWord = " asl  a |  tax |"
-            }
-            else -> {
-                // the indexvar is a real variable, not a register
-                loadX = " ldx  $indexVar |"
-                loadXWord = " lda  $indexVar |  asl  a |  tax |"
-            }
-        }
-
-        return when (ins.opcode) {
-            Opcode.SHL_BYTE -> AsmFragment(" txa |  $loadX  asl  $variable,x |  tax", 10)
-            Opcode.SHR_UBYTE -> AsmFragment(" txa |  $loadX  lsr  $variable,x |  tax", 10)
-            Opcode.SHR_SBYTE -> AsmFragment("$saveX  $loadX  lda  $variable,x |  asl a |  ror  $variable,x  $restoreX", 10)
-            Opcode.SHL_WORD -> AsmFragment("$saveX $loadXWord  asl  $variable,x |  rol  $variable+1,x  $restoreX", 10)
-            Opcode.SHR_UWORD -> AsmFragment("$saveX $loadXWord  lsr  $variable+1,x |  ror  $variable,x  $restoreX", 10)
-            Opcode.SHR_SWORD -> AsmFragment("$saveX $loadXWord  lda  $variable+1,x |  asl a |  ror  $variable+1,x |  ror  $variable,x  $restoreX", 10)
-            Opcode.ROL_BYTE -> AsmFragment(" txa |  $loadX  rol  $variable,x |  tax", 10)
-            Opcode.ROR_BYTE -> AsmFragment(" txa |  $loadX  ror  $variable,x |  tax", 10)
-            Opcode.ROL_WORD -> AsmFragment("$saveX $loadXWord  rol  $variable,x |  rol  $variable+1,x  $restoreX", 10)
-            Opcode.ROR_WORD -> AsmFragment("$saveX $loadXWord  ror  $variable+1,x |  ror  $variable,x  $restoreX", 10)
-            Opcode.ROL2_BYTE -> AsmFragment("$saveX $loadX  lda  $variable,x |  cmp  #\$80 |  rol  $variable,x  $restoreX", 10)
-            Opcode.ROR2_BYTE -> AsmFragment("$saveX $loadX  lda  $variable,x |  lsr  a |  bcc  + |  ora  #\$80 |+ |  sta  $variable,x  $restoreX", 10)
-            Opcode.ROL2_WORD -> AsmFragment(" txa |  $loadXWord  asl  $variable,x |  rol  $variable+1,x |  bcc  + |  inc  $variable,x  |+  |  tax", 30)
-            Opcode.ROR2_WORD -> AsmFragment("$saveX $loadXWord  lsr  $variable+1,x |  ror  $variable,x |  bcc  + |  lda  $variable+1,x |  ora  #\$80 |  sta  $variable+1,x |+  $restoreX", 30)
-            Opcode.INC_INDEXED_VAR_B, Opcode.INC_INDEXED_VAR_UB -> AsmFragment(" txa |  $loadX  inc  $variable,x |  tax", 10)
-            Opcode.DEC_INDEXED_VAR_B, Opcode.DEC_INDEXED_VAR_UB -> AsmFragment(" txa |  $loadX  dec  $variable,x |  tax", 10)
-            Opcode.INC_INDEXED_VAR_W, Opcode.INC_INDEXED_VAR_UW -> AsmFragment("$saveX $loadXWord  inc  $variable,x |  bne  + |  inc  $variable+1,x  |+  $restoreX", 10)
-            Opcode.DEC_INDEXED_VAR_W, Opcode.DEC_INDEXED_VAR_UW -> AsmFragment("$saveX $loadXWord  lda  $variable,x |  bne  + |  dec  $variable+1,x |+ |  dec  $variable,x  $restoreX", 10)
-            Opcode.INC_INDEXED_VAR_FLOAT -> AsmFragment(" lda  #<$variable |  ldy  #>$variable |  $saveX   $loadX   jsr  c64flt.inc_indexed_var_f  $restoreX")
-            Opcode.DEC_INDEXED_VAR_FLOAT -> AsmFragment(" lda  #<$variable |  ldy  #>$variable |  $saveX   $loadX   jsr  c64flt.dec_indexed_var_f  $restoreX")
-
-            else -> null
-        }
-    }
-
-    private fun sameMemOperation(address: Int, ins: Instruction): AsmFragment? {
-        // an in place operation that consists of  push-mem / op / pop-mem
-        val addr = address.toHex()
-        val addrHi = (address+1).toHex()
-        return when(ins.opcode) {
-            Opcode.SHL_BYTE -> AsmFragment(" asl  $addr", 10)
-            Opcode.SHR_UBYTE -> AsmFragment(" lsr  $addr", 10)
-            Opcode.SHR_SBYTE -> AsmFragment(" lda  $addr |  asl  a |  ror  $addr", 10)
-            Opcode.SHL_WORD -> AsmFragment(" asl  $addr |  rol  $addrHi", 10)
-            Opcode.SHR_UWORD -> AsmFragment(" lsr  $addrHi |  ror  $addr", 10)
-            Opcode.SHR_SWORD -> AsmFragment(" lda  $addrHi |  asl a |  ror  $addrHi |  ror  $addr", 10)
-            Opcode.ROL_BYTE -> AsmFragment(" rol  $addr", 10)
-            Opcode.ROR_BYTE -> AsmFragment(" ror  $addr", 10)
-            Opcode.ROL_WORD -> AsmFragment(" rol  $addr |  rol  $addrHi", 10)
-            Opcode.ROR_WORD -> AsmFragment(" ror  $addrHi |  ror  $addr", 10)
-            Opcode.ROL2_BYTE -> AsmFragment(" lda  $addr |  cmp  #\$80 |  rol  $addr", 10)
-            Opcode.ROR2_BYTE -> AsmFragment(" lda  $addr |  lsr  a |  bcc  + |  ora  #\$80 |+ |  sta  $addr", 10)
-            Opcode.ROL2_WORD -> AsmFragment(" lda  $addr |  cmp #\$80 |  rol  $addr |  rol  $addrHi", 10)
-            Opcode.ROR2_WORD -> AsmFragment(" lsr  $addrHi |  ror  $addr |  bcc  + |  lda  $addrHi |  ora  #$80 |  sta  $addrHi |+", 20)
-            else -> null
-        }
-    }
-
-    private fun sameVarOperation(variable: String, ins: Instruction): AsmFragment? {
-        // an in place operation that consists of a push-var / op / pop-var
-        return when(ins.opcode) {
-            Opcode.SHL_BYTE -> {
-                when (variable) {
-                    "A" -> AsmFragment(" asl  a", 10)
-                    "X" -> AsmFragment(" txa |  asl  a |  tax", 10)
-                    "Y" -> AsmFragment(" tya |  asl  a |  tay", 10)
-                    else -> AsmFragment(" asl  $variable", 10)
-                }
-            }
-            Opcode.SHR_UBYTE -> {
-                when (variable) {
-                    "A" -> AsmFragment(" lsr  a", 10)
-                    "X" -> AsmFragment(" txa |  lsr  a |  tax", 10)
-                    "Y" -> AsmFragment(" tya |  lsr  a |  tay", 10)
-                    else -> AsmFragment(" lsr  $variable", 10)
-                }
-            }
-            Opcode.SHR_SBYTE -> {
-                // arithmetic shift right (keep sign bit)
-                when (variable) {
-                    "A" -> AsmFragment(" cmp  #$80 |  ror  a", 10)
-                    "X" -> AsmFragment(" txa |  cmp  #$80 |  ror  a |  tax", 10)
-                    "Y" -> AsmFragment(" tya |  cmp  #$80 |  ror  a |  tay", 10)
-                    else -> AsmFragment(" lda  $variable |  asl  a  | ror  $variable", 10)
-                }
-            }
-            Opcode.SHL_WORD -> {
-                AsmFragment(" asl  $variable |  rol  $variable+1", 10)
-            }
-            Opcode.SHR_UWORD -> {
-                AsmFragment(" lsr  $variable+1 |  ror  $variable", 10)
-            }
-            Opcode.SHR_SWORD -> {
-                // arithmetic shift right (keep sign bit)
-                AsmFragment(" lda  $variable+1 |  asl  a |  ror  $variable+1 |  ror  $variable", 10)
-            }
-            Opcode.ROL_BYTE -> {
-                when (variable) {
-                    "A" -> AsmFragment(" rol  a", 10)
-                    "X" -> AsmFragment(" txa |  rol  a |  tax", 10)
-                    "Y" -> AsmFragment(" tya |  rol  a |  tay", 10)
-                    else -> AsmFragment(" rol  $variable", 10)
-                }
-            }
-            Opcode.ROR_BYTE -> {
-                when (variable) {
-                    "A" -> AsmFragment(" ror  a", 10)
-                    "X" -> AsmFragment(" txa |  ror  a |  tax", 10)
-                    "Y" -> AsmFragment(" tya |  ror  a |  tay", 10)
-                    else -> AsmFragment(" ror  $variable", 10)
-                }
-            }
-            Opcode.ROL_WORD -> {
-                AsmFragment(" rol  $variable |  rol  $variable+1", 10)
-            }
-            Opcode.ROR_WORD -> {
-                AsmFragment(" ror  $variable+1 |  ror  $variable", 10)
-            }
-            Opcode.ROL2_BYTE -> {       // 8-bit rol
-                when (variable) {
-                    "A" -> AsmFragment(" cmp  #\$80 |  rol  a", 10)
-                    "X" -> AsmFragment(" txa |  cmp  #\$80 |  rol  a |  tax", 10)
-                    "Y" -> AsmFragment(" tya |  cmp  #\$80 |  rol  a |  tay", 10)
-                    else -> AsmFragment(" lda  $variable |  cmp  #\$80  | rol  $variable", 10)
-                }
-            }
-            Opcode.ROR2_BYTE -> {       // 8-bit ror
-                when (variable) {
-                    "A" -> AsmFragment(" lsr  a | bcc  + |  ora  #\$80  |+", 10)
-                    "X" -> AsmFragment(" txa |  lsr  a |  bcc  + |  ora  #\$80  |+ |  tax", 10)
-                    "Y" -> AsmFragment(" tya |  lsr  a |  bcc  + |  ora  #\$80  |+ |  tay", 10)
-                    else -> AsmFragment(" lda  $variable |  lsr  a |  bcc  + |  ora  #\$80 |+ |  sta  $variable", 10)
-                }
-            }
-            Opcode.ROL2_WORD -> {
-                AsmFragment(" lda  $variable |  cmp #\$80 |  rol  $variable |  rol  $variable+1", 10)
-            }
-            Opcode.ROR2_WORD -> {
-                AsmFragment(" lsr  $variable+1 |  ror  $variable |  bcc  + |  lda  $variable+1 |  ora  #\$80 |  sta  $variable+1 |+", 30)
-            }
-            else -> null
-        }
-    }
-
-    private class AsmFragment(val asm: String, var segmentSize: Int=0)
-}

DeprecatedStackVm/src/compiler/target/c64/codegen/SimpleAsm.kt

@@ -1,559 +0,0 @@
-package compiler.target.c64.codegen
-
-import prog8.compiler.CompilerException
-import prog8.compiler.intermediate.Instruction
-import prog8.compiler.intermediate.IntermediateProgram
-import prog8.compiler.intermediate.LabelInstr
-import prog8.compiler.intermediate.Opcode
-import prog8.compiler.target.c64.MachineDefinition.C64Zeropage
-import prog8.compiler.target.c64.MachineDefinition.ESTACK_HI_HEX
-import prog8.compiler.target.c64.MachineDefinition.ESTACK_HI_PLUS1_HEX
-import prog8.compiler.target.c64.MachineDefinition.ESTACK_LO_HEX
-import prog8.compiler.target.c64.MachineDefinition.ESTACK_LO_PLUS1_HEX
-import prog8.compiler.target.c64.MachineDefinition.ESTACK_LO_PLUS2_HEX
-import prog8.compiler.toHex
-import prog8.vm.stackvm.Syscall
-import prog8.vm.stackvm.syscallsForStackVm
-
-
-// note: see https://wiki.nesdev.com/w/index.php/6502_assembly_optimisations
-
-
-private var breakpointCounter = 0
-
-internal fun simpleInstr2Asm(ins: Instruction, block: IntermediateProgram.ProgramBlock): String? {
-    // a label 'instruction' is simply translated into a asm label
-    if(ins is LabelInstr) {
-        val labelresult =
-                if(ins.name.startsWith("${block.name}."))
-                    ins.name.substring(block.name.length+1)
-                else
-                    ins.name
-        return if(ins.asmProc) labelresult+"\t\t.proc" else labelresult
-    }
-
-    // simple opcodes that are translated directly into one or a few asm instructions
-    return when(ins.opcode) {
-        Opcode.LINE -> " ;\tsrc line: ${ins.callLabel}"
-        Opcode.NOP -> " nop"      // shouldn't be present anymore though
-        Opcode.START_PROCDEF -> ""  // is done as part of a label
-        Opcode.END_PROCDEF -> " .pend"
-        Opcode.TERMINATE -> " brk"
-        Opcode.SEC -> " sec"
-        Opcode.CLC -> " clc"
-        Opcode.SEI -> " sei"
-        Opcode.CLI -> " cli"
-        Opcode.CARRY_TO_A -> " lda  #0 |  adc  #0"
-        Opcode.JUMP -> {
-            if(ins.callLabel!=null)
-                " jmp  ${ins.callLabel}"
-            else
-                " jmp  ${hexVal(ins)}"
-        }
-        Opcode.CALL -> {
-            if(ins.callLabel!=null)
-                " jsr  ${ins.callLabel}"
-            else
-                " jsr  ${hexVal(ins)}"
-        }
-        Opcode.RETURN -> " rts"
-        Opcode.RSAVE -> {
-            // save cpu status flag and all registers A, X, Y.
-            // see http://6502.org/tutorials/register_preservation.html
-            " php |  sta  ${C64Zeropage.SCRATCH_REG} | pha  | txa  | pha  | tya  | pha  | lda  ${C64Zeropage.SCRATCH_REG}"
-        }
-        Opcode.RRESTORE -> {
-            // restore all registers and cpu status flag
-            " pla |  tay |  pla |  tax |  pla |  plp"
-        }
-        Opcode.RSAVEX -> " sta  ${C64Zeropage.SCRATCH_REG} |  txa |  pha |  lda  ${C64Zeropage.SCRATCH_REG}"
-        Opcode.RRESTOREX -> " sta  ${C64Zeropage.SCRATCH_REG} |  pla |  tax |  lda  ${C64Zeropage.SCRATCH_REG}"
-        Opcode.DISCARD_BYTE -> " inx"
-        Opcode.DISCARD_WORD -> " inx"
-        Opcode.DISCARD_FLOAT -> " inx |  inx |  inx"
-        Opcode.DUP_B -> {
-            " lda $ESTACK_LO_PLUS1_HEX,x | sta $ESTACK_LO_HEX,x | dex | ;DUP_B "
-        }
-        Opcode.DUP_W -> {
-            " lda $ESTACK_LO_PLUS1_HEX,x | sta $ESTACK_LO_HEX,x | lda $ESTACK_HI_PLUS1_HEX,x | sta $ESTACK_HI_HEX,x | dex "
-        }
-
-        Opcode.CMP_B, Opcode.CMP_UB -> {
-            " inx | lda $ESTACK_LO_HEX,x | cmp #${ins.arg!!.integerValue().toHex()} | ;CMP_B "
-        }
-
-        Opcode.CMP_W, Opcode.CMP_UW -> {
-            """
-            inx
-            lda   $ESTACK_HI_HEX,x
-            cmp   #>${ins.arg!!.integerValue().toHex()}
-            bne   +
-            lda   $ESTACK_LO_HEX,x
-            cmp   #<${ins.arg.integerValue().toHex()}
-            ; bne   +    not necessary?
-            ; lda   #0   not necessary?
-+                           
-            """
-        }
-
-        Opcode.INLINE_ASSEMBLY ->  "@inline@" + (ins.callLabel2 ?: "")      // All of the inline assembly is stored in the calllabel2 property. the '@inline@' is a special marker to accept it.
-        Opcode.INCLUDE_FILE -> {
-            val offset = if(ins.arg==null) "" else ", ${ins.arg.integerValue()}"
-            val length = if(ins.arg2==null) "" else ", ${ins.arg2.integerValue()}"
-            " .binary  \"${ins.callLabel}\" $offset $length"
-        }
-        Opcode.SYSCALL -> {
-            if (ins.arg!!.numericValue() in syscallsForStackVm.map { it.callNr })
-                throw CompilerException("cannot translate vm syscalls to real assembly calls - use *real* subroutine calls instead. Syscall ${ins.arg.numericValue()}")
-            val call = Syscall.values().find { it.callNr==ins.arg.numericValue() }
-            when(call) {
-                Syscall.FUNC_SIN,
-                Syscall.FUNC_COS,
-                Syscall.FUNC_ABS,
-                Syscall.FUNC_TAN,
-                Syscall.FUNC_ATAN,
-                Syscall.FUNC_LN,
-                Syscall.FUNC_LOG2,
-                Syscall.FUNC_SQRT,
-                Syscall.FUNC_RAD,
-                Syscall.FUNC_DEG,
-                Syscall.FUNC_ROUND,
-                Syscall.FUNC_FLOOR,
-                Syscall.FUNC_CEIL,
-                Syscall.FUNC_RNDF,
-                Syscall.FUNC_ANY_F,
-                Syscall.FUNC_ALL_F,
-                Syscall.FUNC_MAX_F,
-                Syscall.FUNC_MIN_F,
-                Syscall.FUNC_SUM_F -> " jsr  c64flt.${call.name.toLowerCase()}"
-                null -> ""
-                else -> " jsr  prog8_lib.${call.name.toLowerCase()}"
-            }
-        }
-        Opcode.BREAKPOINT -> {
-            breakpointCounter++
-            "_prog8_breakpoint_$breakpointCounter\tnop"
-        }
-
-        Opcode.PUSH_BYTE -> {
-            " lda  #${hexVal(ins)} |  sta  $ESTACK_LO_HEX,x |  dex"
-        }
-        Opcode.PUSH_WORD -> {
-            val value = hexVal(ins)
-            " lda  #<$value |  sta  $ESTACK_LO_HEX,x |  lda  #>$value |  sta  $ESTACK_HI_HEX,x |  dex"
-        }
-        Opcode.PUSH_FLOAT -> {
-            val floatConst = getFloatConst(ins.arg!!)
-            " lda  #<$floatConst |  ldy  #>$floatConst |  jsr  c64flt.push_float"
-        }
-        Opcode.PUSH_VAR_BYTE -> {
-            when(ins.callLabel) {
-                "X" -> throw CompilerException("makes no sense to push X, it's used as a stack pointer itself. You should probably not use the X register (or only in trivial assignments)")
-                "A" -> " sta  $ESTACK_LO_HEX,x |  dex"
-                "Y" -> " tya |  sta  $ESTACK_LO_HEX,x |  dex"
-                else -> " lda  ${ins.callLabel} |  sta  $ESTACK_LO_HEX,x |  dex"
-            }
-        }
-        Opcode.PUSH_VAR_WORD -> {
-            " lda  ${ins.callLabel} |  sta  $ESTACK_LO_HEX,x |  lda  ${ins.callLabel}+1 |    sta  $ESTACK_HI_HEX,x |  dex"
-        }
-        Opcode.PUSH_VAR_FLOAT -> " lda  #<${ins.callLabel} |  ldy  #>${ins.callLabel}|  jsr  c64flt.push_float"
-        Opcode.PUSH_MEM_B, Opcode.PUSH_MEM_UB -> {
-            """
-                lda  ${hexVal(ins)}
-                sta  $ESTACK_LO_HEX,x
-                dex
-                """
-        }
-        Opcode.PUSH_MEM_W, Opcode.PUSH_MEM_UW -> {
-            """
-                lda  ${hexVal(ins)}
-                sta  $ESTACK_LO_HEX,x
-                lda  ${hexValPlusOne(ins)}
-                sta  $ESTACK_HI_HEX,x
-                dex
-                """
-        }
-        Opcode.PUSH_MEM_FLOAT -> {
-            " lda  #<${hexVal(ins)} |  ldy  #>${hexVal(ins)}|  jsr  c64flt.push_float"
-        }
-        Opcode.PUSH_MEMREAD -> {
-            """
-                lda  $ESTACK_LO_PLUS1_HEX,x
-                sta  (+) +1
-                lda  $ESTACK_HI_PLUS1_HEX,x
-                sta  (+) +2
-+               lda  65535    ; modified
-                sta  $ESTACK_LO_PLUS1_HEX,x
-                """
-        }
-
-        Opcode.PUSH_REGAY_WORD -> {
-            " sta  $ESTACK_LO_HEX,x |  tya |  sta  $ESTACK_HI_HEX,x |  dex "
-        }
-        Opcode.PUSH_ADDR_HEAPVAR -> {
-            " lda  #<${ins.callLabel} |  sta  $ESTACK_LO_HEX,x |  lda  #>${ins.callLabel}  |  sta  $ESTACK_HI_HEX,x |  dex"
-        }
-        Opcode.POP_REGAX_WORD -> throw AssemblyError("cannot load X register from stack because it's used as the stack pointer itself")
-        Opcode.POP_REGXY_WORD -> throw AssemblyError("cannot load X register from stack because it's used as the stack pointer itself")
-        Opcode.POP_REGAY_WORD -> {
-            " inx |  lda  $ESTACK_LO_HEX,x |  ldy  $ESTACK_HI_HEX,x "
-        }
-
-        Opcode.READ_INDEXED_VAR_BYTE -> {
-            """
-                ldy  $ESTACK_LO_PLUS1_HEX,x
-                lda  ${ins.callLabel},y
-                sta  $ESTACK_LO_PLUS1_HEX,x
-                """
-        }
-        Opcode.READ_INDEXED_VAR_WORD -> {
-            """
-                lda  $ESTACK_LO_PLUS1_HEX,x
-                asl  a
-                tay
-                lda  ${ins.callLabel},y
-                sta  $ESTACK_LO_PLUS1_HEX,x
-                lda  ${ins.callLabel}+1,y
-                sta  $ESTACK_HI_PLUS1_HEX,x
-                """
-        }
-        Opcode.READ_INDEXED_VAR_FLOAT -> {
-            """
-                lda  #<${ins.callLabel}
-                ldy  #>${ins.callLabel}
-                jsr  c64flt.push_float_from_indexed_var
-                """
-        }
-        Opcode.WRITE_INDEXED_VAR_BYTE -> {
-            """
-                inx
-                ldy  $ESTACK_LO_HEX,x
-                inx
-                lda  $ESTACK_LO_HEX,x
-                sta  ${ins.callLabel},y
-                """
-        }
-        Opcode.WRITE_INDEXED_VAR_WORD -> {
-            """
-                inx
-                lda  $ESTACK_LO_HEX,x
-                asl  a
-                tay
-                inx
-                lda  $ESTACK_LO_HEX,x
-                sta  ${ins.callLabel},y
-                lda  $ESTACK_HI_HEX,x
-                sta  ${ins.callLabel}+1,y
-                """
-        }
-        Opcode.WRITE_INDEXED_VAR_FLOAT -> {
-            """
-                lda  #<${ins.callLabel}
-                ldy  #>${ins.callLabel}
-                jsr  c64flt.pop_float_to_indexed_var
-                """
-        }
-        Opcode.POP_MEM_BYTE -> {
-            """
-                inx
-                lda  $ESTACK_LO_HEX,x
-                sta  ${hexVal(ins)}
-                """
-        }
-        Opcode.POP_MEM_WORD -> {
-            """
-                inx
-                lda  $ESTACK_LO_HEX,x
-                sta  ${hexVal(ins)}
-                lda  $ESTACK_HI_HEX,x
-                sta  ${hexValPlusOne(ins)}
-                """
-        }
-        Opcode.POP_MEM_FLOAT -> {
-            " lda  ${hexVal(ins)} |  ldy  ${hexValPlusOne(ins)} |  jsr  c64flt.pop_float"
-        }
-        Opcode.POP_MEMWRITE -> {
-            """
-                inx
-                lda  $ESTACK_LO_HEX,x
-                sta  (+) +1
-                lda  $ESTACK_HI_HEX,x
-                sta  (+) +2
-                inx
-                lda  $ESTACK_LO_HEX,x
-+               sta  65535       ; modified
-                """
-        }
-
-        Opcode.POP_VAR_BYTE -> {
-            when (ins.callLabel) {
-                "X" -> throw CompilerException("makes no sense to pop X, it's used as a stack pointer itself")
-                "A" -> " inx |  lda  $ESTACK_LO_HEX,x"
-                "Y" -> " inx |  ldy  $ESTACK_LO_HEX,x"
-                else -> " inx |  lda  $ESTACK_LO_HEX,x |  sta  ${ins.callLabel}"
-            }
-        }
-        Opcode.POP_VAR_WORD -> {
-            " inx |  lda  $ESTACK_LO_HEX,x |  ldy  $ESTACK_HI_HEX,x |  sta  ${ins.callLabel} |  sty  ${ins.callLabel}+1"
-        }
-        Opcode.POP_VAR_FLOAT -> {
-            " lda  #<${ins.callLabel} |  ldy  #>${ins.callLabel} |  jsr  c64flt.pop_float"
-        }
-
-        Opcode.INC_VAR_UB, Opcode.INC_VAR_B -> {
-            when (ins.callLabel) {
-                "A" -> " clc |  adc  #1"
-                "X" -> " inx"
-                "Y" -> " iny"
-                else -> " inc  ${ins.callLabel}"
-            }
-        }
-        Opcode.INC_VAR_UW, Opcode.INC_VAR_W -> {
-            " inc  ${ins.callLabel} |  bne  + |  inc  ${ins.callLabel}+1 |+"
-        }
-        Opcode.INC_VAR_F -> {
-            """
-                lda  #<${ins.callLabel}
-                ldy  #>${ins.callLabel}
-                jsr  c64flt.inc_var_f
-                """
-        }
-        Opcode.POP_INC_MEMORY -> {
-            """
-                inx
-                lda  $ESTACK_LO_HEX,x
-                sta  (+) +1
-                lda  $ESTACK_HI_HEX,x
-                sta  (+) +2
-+               inc  65535     ; modified
-                """
-        }
-        Opcode.POP_DEC_MEMORY -> {
-            """
-                inx
-                lda  $ESTACK_LO_HEX,x
-                sta  (+) +1
-                lda  $ESTACK_HI_HEX,x
-                sta  (+) +2
-+               dec  65535     ; modified
-                """
-        }
-        Opcode.DEC_VAR_UB, Opcode.DEC_VAR_B -> {
-            when (ins.callLabel) {
-                "A" -> " sec |  sbc  #1"
-                "X" -> " dex"
-                "Y" -> " dey"
-                else -> " dec  ${ins.callLabel}"
-            }
-        }
-        Opcode.DEC_VAR_UW, Opcode.DEC_VAR_W -> {
-            " lda  ${ins.callLabel} |  bne  + |  dec  ${ins.callLabel}+1 |+ |  dec  ${ins.callLabel}"
-        }
-        Opcode.DEC_VAR_F -> {
-            """
-                lda  #<${ins.callLabel}
-                ldy  #>${ins.callLabel}
-                jsr  c64flt.dec_var_f
-                """
-        }
-        Opcode.INC_MEMORY -> " inc  ${hexVal(ins)}"
-        Opcode.DEC_MEMORY -> " dec  ${hexVal(ins)}"
-        Opcode.INC_INDEXED_VAR_B, Opcode.INC_INDEXED_VAR_UB -> " inx |  txa |  pha |  lda  $ESTACK_LO_HEX,x |  tax |  inc  ${ins.callLabel},x |  pla |  tax"
-        Opcode.DEC_INDEXED_VAR_B, Opcode.DEC_INDEXED_VAR_UB -> " inx |  txa |  pha |  lda  $ESTACK_LO_HEX,x |  tax |  dec  ${ins.callLabel},x |  pla |  tax"
-
-        Opcode.NEG_B -> " jsr  prog8_lib.neg_b"
-        Opcode.NEG_W -> " jsr  prog8_lib.neg_w"
-        Opcode.NEG_F -> " jsr  c64flt.neg_f"
-        Opcode.ABS_B -> " jsr  prog8_lib.abs_b"
-        Opcode.ABS_W -> " jsr  prog8_lib.abs_w"
-        Opcode.ABS_F -> " jsr  c64flt.abs_f"
-        Opcode.POW_F -> " jsr  c64flt.pow_f"
-        Opcode.INV_BYTE -> {
-            """
-                lda  $ESTACK_LO_PLUS1_HEX,x
-                eor  #255
-                sta  $ESTACK_LO_PLUS1_HEX,x
-                """
-        }
-        Opcode.INV_WORD -> " jsr  prog8_lib.inv_word"
-        Opcode.NOT_BYTE -> " jsr  prog8_lib.not_byte"
-        Opcode.NOT_WORD -> " jsr  prog8_lib.not_word"
-        Opcode.BCS -> {
-            val label = ins.callLabel ?: hexVal(ins)
-            " bcs  $label"
-        }
-        Opcode.BCC -> {
-            val label = ins.callLabel ?: hexVal(ins)
-            " bcc  $label"
-        }
-        Opcode.BNEG -> {
-            val label = ins.callLabel ?: hexVal(ins)
-            " bmi  $label"
-        }
-        Opcode.BPOS -> {
-            val label = ins.callLabel ?: hexVal(ins)
-            " bpl  $label"
-        }
-        Opcode.BVC -> {
-            val label = ins.callLabel ?: hexVal(ins)
-            " bvc  $label"
-        }
-        Opcode.BVS -> {
-            val label = ins.callLabel ?: hexVal(ins)
-            " bvs  $label"
-        }
-        Opcode.BZ -> {
-            val label = ins.callLabel ?: hexVal(ins)
-            " beq  $label"
-        }
-        Opcode.BNZ -> {
-            val label = ins.callLabel ?: hexVal(ins)
-            " bne  $label"
-        }
-        Opcode.JZ -> {
-            val label = ins.callLabel ?: hexVal(ins)
-            """
-                inx
-                lda  $ESTACK_LO_HEX,x
-                beq  $label
-                """
-        }
-        Opcode.JZW -> {
-            val label = ins.callLabel ?: hexVal(ins)
-            """
-                inx
-                lda  $ESTACK_LO_HEX,x
-                beq  $label
-                lda  $ESTACK_HI_HEX,x
-                beq  $label
-                """
-        }
-        Opcode.JNZ -> {
-            val label = ins.callLabel ?: hexVal(ins)
-            """
-                inx
-                lda  $ESTACK_LO_HEX,x
-                bne  $label
-                """
-        }
-        Opcode.JNZW -> {
-            val label = ins.callLabel ?: hexVal(ins)
-            """
-                inx
-                lda  $ESTACK_LO_HEX,x
-                bne  $label
-                lda  $ESTACK_HI_HEX,x
-                bne  $label
-                """
-        }
-        Opcode.CAST_B_TO_UB -> ""  // is a no-op, just carry on with the byte as-is
-        Opcode.CAST_UB_TO_B -> ""  // is a no-op, just carry on with the byte as-is
-        Opcode.CAST_W_TO_UW -> ""  // is a no-op, just carry on with the word as-is
-        Opcode.CAST_UW_TO_W -> ""  // is a no-op, just carry on with the word as-is
-        Opcode.CAST_W_TO_UB -> ""  // is a no-op, just carry on with the lsb of the word as-is
-        Opcode.CAST_W_TO_B -> ""  // is a no-op, just carry on with the lsb of the word as-is
-        Opcode.CAST_UW_TO_UB -> ""  // is a no-op, just carry on with the lsb of the uword as-is
-        Opcode.CAST_UW_TO_B -> ""  // is a no-op, just carry on with the lsb of the uword as-is
-        Opcode.CAST_UB_TO_F -> " jsr  c64flt.stack_ub2float"
-        Opcode.CAST_B_TO_F -> " jsr  c64flt.stack_b2float"
-        Opcode.CAST_UW_TO_F -> " jsr  c64flt.stack_uw2float"
-        Opcode.CAST_W_TO_F -> " jsr  c64flt.stack_w2float"
-        Opcode.CAST_F_TO_UB -> " jsr  c64flt.stack_float2ub"
-        Opcode.CAST_F_TO_B -> " jsr  c64flt.stack_float2b"
-        Opcode.CAST_F_TO_UW -> " jsr  c64flt.stack_float2uw"
-        Opcode.CAST_F_TO_W -> " jsr  c64flt.stack_float2w"
-        Opcode.CAST_UB_TO_UW, Opcode.CAST_UB_TO_W -> " lda  #0 |  sta  $ESTACK_HI_PLUS1_HEX,x"     // clear the msb
-        Opcode.CAST_B_TO_UW, Opcode.CAST_B_TO_W -> " lda  $ESTACK_LO_PLUS1_HEX,x |  ${signExtendA("$ESTACK_HI_PLUS1_HEX,x")}"     // sign extend the lsb
-        Opcode.MSB -> " lda  $ESTACK_HI_PLUS1_HEX,x |  sta  $ESTACK_LO_PLUS1_HEX,x"
-        Opcode.MKWORD -> " inx |  lda  $ESTACK_LO_HEX,x |  sta  $ESTACK_HI_PLUS1_HEX,x "
-
-        Opcode.ADD_UB, Opcode.ADD_B -> {        // TODO inline better (pattern with more opcodes)
-            """
-                lda  $ESTACK_LO_PLUS2_HEX,x
-                clc
-                adc  $ESTACK_LO_PLUS1_HEX,x
-                inx
-                sta  $ESTACK_LO_PLUS1_HEX,x
-                """
-        }
-        Opcode.SUB_UB, Opcode.SUB_B -> {        // TODO inline better (pattern with more opcodes)
-            """
-                lda  $ESTACK_LO_PLUS2_HEX,x
-                sec
-                sbc  $ESTACK_LO_PLUS1_HEX,x
-                inx
-                sta  $ESTACK_LO_PLUS1_HEX,x
-                """
-        }
-        Opcode.ADD_W, Opcode.ADD_UW -> "  jsr  prog8_lib.add_w"
-        Opcode.SUB_W, Opcode.SUB_UW -> "  jsr  prog8_lib.sub_w"
-        Opcode.MUL_B, Opcode.MUL_UB -> "  jsr  prog8_lib.mul_byte"
-        Opcode.MUL_W, Opcode.MUL_UW -> "  jsr  prog8_lib.mul_word"
-        Opcode.MUL_F -> "  jsr  c64flt.mul_f"
-        Opcode.ADD_F -> "  jsr  c64flt.add_f"
-        Opcode.SUB_F -> "  jsr  c64flt.sub_f"
-        Opcode.DIV_F -> "  jsr  c64flt.div_f"
-        Opcode.IDIV_UB -> "  jsr  prog8_lib.idiv_ub"
-        Opcode.IDIV_B -> "  jsr  prog8_lib.idiv_b"
-        Opcode.IDIV_W -> "  jsr  prog8_lib.idiv_w"
-        Opcode.IDIV_UW -> "  jsr  prog8_lib.idiv_uw"
-
-        Opcode.AND_BYTE -> "  jsr  prog8_lib.and_b"
-        Opcode.OR_BYTE -> "  jsr  prog8_lib.or_b"
-        Opcode.XOR_BYTE -> "  jsr  prog8_lib.xor_b"
-        Opcode.AND_WORD -> "  jsr  prog8_lib.and_w"
-        Opcode.OR_WORD -> "  jsr  prog8_lib.or_w"
-        Opcode.XOR_WORD -> "  jsr  prog8_lib.xor_w"
-
-        Opcode.BITAND_BYTE -> "  jsr  prog8_lib.bitand_b"
-        Opcode.BITOR_BYTE -> "  jsr  prog8_lib.bitor_b"
-        Opcode.BITXOR_BYTE -> "  jsr  prog8_lib.bitxor_b"
-        Opcode.BITAND_WORD -> "  jsr  prog8_lib.bitand_w"
-        Opcode.BITOR_WORD -> "  jsr  prog8_lib.bitor_w"
-        Opcode.BITXOR_WORD -> "  jsr  prog8_lib.bitxor_w"
-
-        Opcode.REMAINDER_UB -> "  jsr  prog8_lib.remainder_ub"
-        Opcode.REMAINDER_UW -> "  jsr  prog8_lib.remainder_uw"
-
-        Opcode.GREATER_B -> "  jsr  prog8_lib.greater_b"
-        Opcode.GREATER_UB -> "  jsr  prog8_lib.greater_ub"
-        Opcode.GREATER_W -> "  jsr  prog8_lib.greater_w"
-        Opcode.GREATER_UW -> "  jsr  prog8_lib.greater_uw"
-        Opcode.GREATER_F -> "  jsr  c64flt.greater_f"
-
-        Opcode.GREATEREQ_B -> "  jsr  prog8_lib.greatereq_b"
-        Opcode.GREATEREQ_UB -> "  jsr  prog8_lib.greatereq_ub"
-        Opcode.GREATEREQ_W -> "  jsr  prog8_lib.greatereq_w"
-        Opcode.GREATEREQ_UW -> "  jsr  prog8_lib.greatereq_uw"
-        Opcode.GREATEREQ_F -> "  jsr  c64flt.greatereq_f"
-
-        Opcode.EQUAL_BYTE -> "  jsr  prog8_lib.equal_b"
-        Opcode.EQUAL_WORD -> "  jsr  prog8_lib.equal_w"
-        Opcode.EQUAL_F -> "  jsr  c64flt.equal_f"
-        Opcode.NOTEQUAL_BYTE -> "  jsr prog8_lib.notequal_b"
-        Opcode.NOTEQUAL_WORD -> "  jsr prog8_lib.notequal_w"
-        Opcode.NOTEQUAL_F -> "  jsr  c64flt.notequal_f"
-
-        Opcode.LESS_UB -> "  jsr  prog8_lib.less_ub"
-        Opcode.LESS_B -> "  jsr  prog8_lib.less_b"
-        Opcode.LESS_UW -> "  jsr  prog8_lib.less_uw"
-        Opcode.LESS_W -> "  jsr  prog8_lib.less_w"
-        Opcode.LESS_F -> "  jsr  c64flt.less_f"
-
-        Opcode.LESSEQ_UB -> "  jsr  prog8_lib.lesseq_ub"
-        Opcode.LESSEQ_B -> "  jsr  prog8_lib.lesseq_b"
-        Opcode.LESSEQ_UW -> "  jsr  prog8_lib.lesseq_uw"
-        Opcode.LESSEQ_W -> "  jsr  prog8_lib.lesseq_w"
-        Opcode.LESSEQ_F -> "  jsr  c64flt.lesseq_f"
-
-        Opcode.SHIFTEDL_BYTE -> "  asl  $ESTACK_LO_PLUS1_HEX,x"
-        Opcode.SHIFTEDL_WORD -> "  asl  $ESTACK_LO_PLUS1_HEX,x |  rol  $ESTACK_HI_PLUS1_HEX,x"
-        Opcode.SHIFTEDR_SBYTE -> "  lda  $ESTACK_LO_PLUS1_HEX,x |  asl  a |  ror  $ESTACK_LO_PLUS1_HEX,x"
-        Opcode.SHIFTEDR_UBYTE -> "  lsr  $ESTACK_LO_PLUS1_HEX,x"
-        Opcode.SHIFTEDR_SWORD -> "  lda  $ESTACK_HI_PLUS1_HEX,x |  asl a  |  ror  $ESTACK_HI_PLUS1_HEX,x |  ror  $ESTACK_LO_PLUS1_HEX,x"
-        Opcode.SHIFTEDR_UWORD -> "  lsr  $ESTACK_HI_PLUS1_HEX,x |  ror  $ESTACK_LO_PLUS1_HEX,x"
-
-        else -> null
-    }
-}

DeprecatedStackVm/src/prog8/vm/stackvm/Main.kt

@@ -1,47 +0,0 @@
-package prog8.vm.stackvm
-
-import prog8.printSoftwareHeader
-import prog8.vm.astvm.ScreenDialog
-import java.awt.EventQueue
-import javax.swing.Timer
-import kotlin.system.exitProcess
-
-fun main(args: Array<String>) {
-    stackVmMain(args)
-}
-
-fun stackVmMain(args: Array<String>) {
-    printSoftwareHeader("StackVM")
-
-    if(args.size != 1) {
-        System.err.println("requires one argument: name of stackvm sourcecode file")
-        exitProcess(1)
-    }
-
-    val program = Program.load(args.first())
-    val vm = StackVm(traceOutputFile = null)
-    val dialog = ScreenDialog("StackVM")
-    vm.load(program, dialog.canvas)
-    EventQueue.invokeLater {
-        dialog.pack()
-        dialog.isVisible = true
-        dialog.start()
-
-        val programTimer = Timer(10) { a ->
-            try {
-                vm.step()
-            } catch(bp: VmBreakpointException) {
-                println("Breakpoint: execution halted. Press enter to resume.")
-                readLine()
-            } catch (tx: VmTerminationException) {
-                println("Execution halted: ${tx.message}")
-                (a.source as Timer).stop()
-            }
-        }
-
-        val irqTimer = Timer(1000/60) { a -> vm.irq(a.`when`) }
-
-        programTimer.start()
-        irqTimer.start()
-    }
-}

DeprecatedStackVm/src/prog8/vm/stackvm/Program.kt

@@ -1,302 +0,0 @@
-package prog8.vm.stackvm
-
-import prog8.ast.antlr.unescape
-import prog8.ast.base.*
-import prog8.ast.expressions.AddressOf
-import prog8.ast.expressions.IdentifierReference
-import prog8.compiler.HeapValues
-import prog8.compiler.IntegerOrAddressOf
-import prog8.compiler.intermediate.Instruction
-import prog8.compiler.intermediate.LabelInstr
-import prog8.compiler.intermediate.Opcode
-import prog8.compiler.intermediate.opcodesWithVarArgument
-import prog8.vm.RuntimeValue
-import java.io.File
-import java.util.*
-import java.util.regex.Pattern
-
-class Program (val name: String,
-               val program: MutableList<Instruction>,
-               val variables: Map<String, RuntimeValue>,
-               val memoryPointers: Map<String, Pair<Int, DataType>>,
-               val labels: Map<String, Int>,
-               val memory: Map<Int, List<RuntimeValue>>,
-               val heap: HeapValues)
-{
-    init {
-        // add end of program marker and some sentinel instructions, to correctly connect all others
-        program.add(LabelInstr("____program_end", false))
-        program.add(Instruction(Opcode.TERMINATE))
-        program.add(Instruction(Opcode.NOP))
-    }
-
-    companion object {
-        fun load(filename: String): Program {
-            val lines = File(filename).readLines().withIndex().iterator()
-            val memory = mutableMapOf<Int, List<RuntimeValue>>()
-            val heap = HeapValues()
-            val program = mutableListOf<Instruction>()
-            val variables = mutableMapOf<String, RuntimeValue>()
-            val memoryPointers = mutableMapOf<String, Pair<Int, DataType>>()
-            val labels = mutableMapOf<String, Int>()
-
-            while(lines.hasNext()) {
-                val (lineNr, line) = lines.next()
-                if(line.startsWith(';') || line.isEmpty())
-                    continue
-                else if(line=="%memory")
-                    loadMemory(lines, memory)
-                else if(line=="%heap")
-                    loadHeap(lines, heap)
-                else if(line.startsWith("%block "))
-                    loadBlock(lines, heap, program, variables, memoryPointers, labels)
-                else throw VmExecutionException("syntax error at line ${lineNr + 1}")
-            }
-            return Program(filename, program, variables, memoryPointers, labels, memory, heap)
-        }
-
-        private fun loadBlock(lines: Iterator<IndexedValue<String>>,
-                              heap: HeapValues,
-                              program: MutableList<Instruction>,
-                              variables: MutableMap<String, RuntimeValue>,
-                              memoryPointers: MutableMap<String, Pair<Int, DataType>>,
-                              labels: MutableMap<String, Int>)
-        {
-            while(true) {
-                val (_, line) = lines.next()
-                if(line.isEmpty())
-                    continue
-                else if(line=="%end_block")
-                    return
-                else if(line=="%variables")
-                    loadVars(lines, variables)
-                else if(line=="%memorypointers")
-                    loadMemoryPointers(lines, memoryPointers, heap)
-                else if(line=="%instructions") {
-                    val (blockInstructions, blockLabels) = loadInstructions(lines, heap)
-                    val baseIndex = program.size
-                    program.addAll(blockInstructions)
-                    val labelsWithIndex = blockLabels.mapValues { baseIndex+blockInstructions.indexOf(it.value) }
-                    labels.putAll(labelsWithIndex)
-                }
-            }
-        }
-
-        private fun loadHeap(lines: Iterator<IndexedValue<String>>, heap: HeapValues) {
-            val splitpattern = Pattern.compile("\\s+")
-            val heapvalues = mutableListOf<Triple<Int, DataType, String>>()
-            while(true) {
-                val (_, line) = lines.next()
-                if (line == "%end_heap")
-                    break
-                val parts = line.split(splitpattern, limit=3)
-                val value = Triple(parts[0].toInt(), DataType.valueOf(parts[1].toUpperCase()), parts[2])
-                heapvalues.add(value)
-            }
-            heapvalues.sortedBy { it.first }.forEach {
-                when(it.second) {
-                    DataType.STR, DataType.STR_S -> heap.addString(it.second, unescape(it.third.substring(1, it.third.length - 1), Position("<stackvmsource>", 0, 0, 0)))
-                    DataType.ARRAY_UB, DataType.ARRAY_B,
-                    DataType.ARRAY_UW, DataType.ARRAY_W -> {
-                        val numbers = it.third.substring(1, it.third.length-1).split(',')
-                        val intarray = numbers.map{number->
-                            val num=number.trim()
-                            if(num.startsWith("&")) {
-                                // it's AddressOf
-                                val scopedname = num.substring(1)
-                                val iref = IdentifierReference(scopedname.split('.'), Position("<intermediate>", 0, 0, 0))
-                                val addrOf = AddressOf(iref, Position("<intermediate>", 0, 0, 0))
-                                addrOf.scopedname=scopedname
-                                IntegerOrAddressOf(null, addrOf)
-                            } else {
-                                IntegerOrAddressOf(num.toInt(), null)
-                            }
-                        }.toTypedArray()
-                        heap.addIntegerArray(it.second, intarray)
-                    }
-                    DataType.ARRAY_F -> {
-                        val numbers = it.third.substring(1, it.third.length-1).split(',')
-                        val doublearray = numbers.map{number->number.trim().toDouble()}.toDoubleArray()
-                        heap.addDoublesArray(doublearray)
-                    }
-                    in NumericDatatypes -> throw VmExecutionException("invalid heap value type ${it.second}")
-                    else -> throw VmExecutionException("weird datatype")
-                }
-            }
-        }
-
-        private fun loadInstructions(lines: Iterator<IndexedValue<String>>, heap: HeapValues): Pair<MutableList<Instruction>, Map<String, Instruction>> {
-            val instructions = mutableListOf<Instruction>()
-            val labels = mutableMapOf<String, Instruction>()
-            val splitpattern = Pattern.compile("\\s+")
-            val nextInstructionLabels = Stack<String>()     // more than one label can occur on the isSameAs line
-
-            while(true) {
-                val (lineNr, line) = lines.next()
-                if(line.isEmpty())
-                    continue
-                if(line=="%end_instructions")
-                    return Pair(instructions, labels)
-                if(!line.startsWith(' ') && line.endsWith(':')) {
-                    nextInstructionLabels.push(line.substring(0, line.length-1))
-                } else if(line.startsWith(' ')) {
-                    val parts = line.trimStart().split(splitpattern, limit = 2)
-                    val opcodeStr = parts[0].toUpperCase()
-                    val opcode= Opcode.valueOf(if(opcodeStr.startsWith('_')) opcodeStr.substring(1) else opcodeStr)
-                    val args = if(parts.size==2) parts[1] else null
-                    val instruction = when(opcode) {
-                        Opcode.LINE -> Instruction(opcode, null, callLabel = args)
-                        Opcode.JUMP, Opcode.CALL, Opcode.BNEG, Opcode.BPOS,
-                        Opcode.BZ, Opcode.BNZ, Opcode.BCS, Opcode.BCC,
-                        Opcode.JZ, Opcode.JNZ, Opcode.JZW, Opcode.JNZW -> {
-                            if(args!!.startsWith('$')) {
-                                Instruction(opcode, RuntimeValue(DataType.UWORD, args.substring(1).toInt(16)))
-                            } else {
-                                Instruction(opcode, callLabel = args)
-                            }
-                        }
-                        in opcodesWithVarArgument -> {
-                            val withoutQuotes =
-                                    if(args!!.startsWith('"') && args.endsWith('"'))
-                                        args.substring(1, args.length-1) else args
-
-                            Instruction(opcode, callLabel = withoutQuotes)
-                        }
-                        Opcode.SYSCALL -> {
-                            if(args!! in syscallNames) {
-                                val call = Syscall.valueOf(args)
-                                Instruction(opcode, RuntimeValue(DataType.UBYTE, call.callNr))
-                            } else {
-                                val args2 = args.replace('.', '_')
-                                if(args2 in syscallNames) {
-                                    val call = Syscall.valueOf(args2)
-                                    Instruction(opcode, RuntimeValue(DataType.UBYTE, call.callNr))
-                                } else {
-                                    // the syscall is not yet implemented. emit a stub.
-                                    Instruction(Opcode.SYSCALL, RuntimeValue(DataType.UBYTE, Syscall.SYSCALLSTUB.callNr), callLabel = args2)
-                                }
-                            }
-                        }
-                        Opcode.INCLUDE_FILE -> {
-                            val argparts = args!!.split(' ')
-                            val filename = argparts[0]
-                            val offset = if(argparts.size>=2 && argparts[1]!="null") getArgValue(argparts[1], heap) else null
-                            val length = if(argparts.size>=3 && argparts[2]!="null") getArgValue(argparts[2], heap) else null
-                            Instruction(opcode, offset, length, filename)
-                        }
-                        else -> {
-                            Instruction(opcode, getArgValue(args, heap))
-                        }
-                    }
-                    instructions.add(instruction)
-                    while(nextInstructionLabels.isNotEmpty()) {
-                        val label = nextInstructionLabels.pop()
-                        labels[label] = instruction
-                    }
-                } else throw VmExecutionException("syntax error at line ${lineNr + 1}")
-            }
-        }
-
-        private fun getArgValue(args: String?, heap: HeapValues): RuntimeValue? {
-            if(args==null)
-                return null
-            if(args[0]=='"' && args[args.length-1]=='"') {
-                throw VmExecutionException("encountered a string arg value, but all strings should already have been moved into the heap")
-            }
-            val (type, valueStr) = args.split(':')
-            return when(type) {
-                "b" -> RuntimeValue(DataType.BYTE, valueStr.toShort(16))
-                "ub" -> RuntimeValue(DataType.UBYTE, valueStr.toShort(16))
-                "w" -> RuntimeValue(DataType.WORD, valueStr.toInt(16))
-                "uw" -> RuntimeValue(DataType.UWORD, valueStr.toInt(16))
-                "f" -> RuntimeValue(DataType.FLOAT, valueStr.toDouble())
-                "heap" -> {
-                    val heapId = valueStr.toInt()
-                    RuntimeValue(heap.get(heapId).type, heapId = heapId)
-                }
-                else -> throw VmExecutionException("invalid datatype $type")
-            }
-        }
-
-        private fun loadVars(lines: Iterator<IndexedValue<String>>,
-                             vars: MutableMap<String, RuntimeValue>) {
-            val splitpattern = Pattern.compile("\\s+")
-            while(true) {
-                val (_, line) = lines.next()
-                if(line=="%end_variables")
-                    return
-                val (name, typeStr, valueStr) = line.split(splitpattern, limit = 3)
-                if(valueStr[0] !='"' && ':' !in valueStr)
-                    throw VmExecutionException("missing value type character")
-                val value = when(val type = DataType.valueOf(typeStr.toUpperCase())) {
-                    DataType.UBYTE -> RuntimeValue(DataType.UBYTE, valueStr.substring(3).substringBefore(' ').toShort(16))// TODO process ZP and struct info?
-                    DataType.BYTE -> RuntimeValue(DataType.BYTE, valueStr.substring(2).substringBefore(' ').toShort(16))// TODO process ZP and struct info?
-                    DataType.UWORD -> RuntimeValue(DataType.UWORD, valueStr.substring(3).substringBefore(' ').toInt(16))// TODO process ZP and struct info?
-                    DataType.WORD -> RuntimeValue(DataType.WORD, valueStr.substring(2).substringBefore(' ').toInt(16))// TODO process ZP and struct info?
-                    DataType.FLOAT -> RuntimeValue(DataType.FLOAT, valueStr.substring(2).substringBefore(' ').toDouble())// TODO process ZP and struct info?
-                    in StringDatatypes -> {
-                        if(valueStr.startsWith('"') && valueStr.endsWith('"'))
-                            throw VmExecutionException("encountered a var with a string value, but all string values should already have been moved into the heap")
-                        else if(!valueStr.startsWith("heap:"))
-                            throw VmExecutionException("invalid string value, should be a heap reference")
-                        else {
-                            val heapId = valueStr.substring(5).substringBefore(' ').toInt()     // TODO process ZP and struct info?
-                            RuntimeValue(type, heapId = heapId)
-                        }
-                    }
-                    in ArrayDatatypes -> {
-                        if(!valueStr.startsWith("heap:"))
-                            throw VmExecutionException("invalid array value, should be a heap reference")
-                        else {
-                            val heapId = valueStr.substring(5).substringBefore(' ').toInt()     // TODO process ZP and struct info?
-                            RuntimeValue(type, heapId = heapId)
-                        }
-                    }
-                    else -> throw VmExecutionException("weird datatype")
-                }
-                vars[name] = value
-            }
-        }
-
-        private fun loadMemoryPointers(lines: Iterator<IndexedValue<String>>,
-                                       pointers: MutableMap<String, Pair<Int, DataType>>,
-                                       heap: HeapValues) {
-            val splitpattern = Pattern.compile("\\s+")
-            while(true) {
-                val (_, line) = lines.next()
-                if(line=="%end_memorypointers")
-                    return
-                val (name, typeStr, valueStr) = line.split(splitpattern, limit = 3)
-                if(valueStr[0] !='"' && ':' !in valueStr)
-                    throw VmExecutionException("missing value type character")
-                val type = DataType.valueOf(typeStr.toUpperCase())
-                val value = getArgValue(valueStr, heap)!!.integerValue()
-                pointers[name] = Pair(value, type)
-            }
-        }
-
-        private fun loadMemory(lines: Iterator<IndexedValue<String>>, memory: MutableMap<Int, List<RuntimeValue>>): Map<Int, List<RuntimeValue>> {
-            while(true) {
-                val (lineNr, line) = lines.next()
-                if(line=="%end_memory")
-                    return memory
-                val address = line.substringBefore(' ').toInt(16)
-                val rest = line.substringAfter(' ').trim()
-                if(rest.startsWith('"')) {
-                    TODO("memory init with char/string")
-                } else {
-                    val valueStrings = rest.split(' ')
-                    val values = mutableListOf<RuntimeValue>()
-                    valueStrings.forEach {
-                        when(it.length) {
-                            2 -> values.add(RuntimeValue(DataType.UBYTE, it.toShort(16)))
-                            4 -> values.add(RuntimeValue(DataType.UWORD, it.toInt(16)))
-                            else -> throw VmExecutionException("invalid value at line $lineNr+1")
-                        }
-                    }
-                    memory[address] = values
-                }
-            }
-        }
-    }
-}

LICENSE

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

README.md

@@ -1,64 +1,81 @@
-[![saythanks](https://img.shields.io/badge/say-thanks-ff69b4.svg)](https://saythanks.io/to/irmen)
+[![Documentation](https://readthedocs.org/projects/prog8/badge/?version=latest)](https://prog8.readthedocs.io/)
-[![Build Status](https://travis-ci.org/irmen/prog8.svg?branch=master)](https://travis-ci.org/irmen/prog8)
 
-Prog8 - Structured Programming Language for 8-bit 6502/6510 microprocessors
+Prog8 - Structured Programming Language for 8-bit 6502/65c02 microprocessors
-===========================================================================
+============================================================================
 
 *Written by Irmen de Jong (irmen@razorvine.net)*
 
-*Software license: GNU GPL 3.0, see file LICENSE*
+This is a structured programming language for the 8-bit 6502/6510/65c02 microprocessor from the late 1970's and 1980's
-
-
-This is a structured programming language for the 8-bit 6502/6510 microprocessor from the late 1970's and 1980's
 as used in many home computers from that era. It is a medium to low level programming language,
-which aims to provide many conveniences over raw assembly code (even when using a macro assembler):
+which aims to provide many conveniences over raw assembly code (even when using a macro assembler).
 
-- reduction of source code length
+Documentation
+-------------
+Full documentation (syntax reference, how to use the language and the compiler, etc.) can be found at:
+https://prog8.readthedocs.io/
+
+Software license
+----------------
+GNU GPL 3.0, see file LICENSE
+
+- prog8 (the compiler + libraries) is licensed under GNU GPL 3.0
+- *exception:* the resulting files created by running the compiler are free to use in whatever way desired.
+
+
+What does Prog8 provide?
+------------------------
+
+- reduction of source code length over raw assembly
+- fast execution speed due to compilation to native assembly code. It's possible to write certain raster interrupt 'demoscene' effects purely in Prog8.
 - modularity, symbol scoping, subroutines
 - various data types other than just bytes (16-bit words, floats, strings)
-- automatic variable allocations, automatic string and array variables and string sharing
+- floating point math is supported if the target system provides floating point library routines (C64 and Cx16 both do)
-- subroutines with a input- and output parameter signature
+- strings can contain escaped characters but also many symbols directly if they have a petscii equivalent, such as "♠♥♣♦π▚●○╳". Characters like ^, _, \, {, } and | are also accepted and converted to the closest petscii equivalents.
-- constant folding in expressions
+- automatic static variable allocations, automatic string and array variables and string sharing
+- subroutines with input parameters and result values
+- high-level program optimizations
+- small program boilerplate/compilersupport overhead
+- programs can be run multiple times without reloading because of automatic variable (re)initializations.
 - conditional branches
-- 'when' statement to provide a concise jump table alternative to if/elseif chains
+- ``when`` statement to provide a concise jump table alternative to if/elseif chains
-- structs to group together sets of variables and manipulate them at once
+- ``in`` expression for concise and efficient multi-value/containment check 
-- floating point operations  (requires the C64 Basic ROM routines for this)
+- many built-in functions such as ``sin``, ``cos``, ``rnd``, ``abs``, ``min``, ``max``, ``sqrt``, ``msb``, ``rol``, ``ror``, ``swap``, ``sort`` and ``reverse``
-- abstracting away low level aspects such as ZeroPage handling, program startup, explicit memory addresses
+- various powerful built-in libraries to do I/O, number conversions, graphics and more  
-- various code optimizations (code structure, logical and numerical expressions, unused code removal...)
+- convenience abstractions for low level aspects such as ZeroPage handling, program startup, explicit memory addresses
 - inline assembly allows you to have full control when every cycle or byte matters
-- many built-in functions such as ``sin``, ``cos``, ``rnd``, ``abs``, ``min``, ``max``, ``sqrt``, ``msb``, ``rol``, ``ror``, ``swap``, ``memset``, ``memcopy``
+- supports the sixteen 'virtual' 16-bit registers R0 - R15 from the Commander X16, and provides them also on the C64.
+- encode strings and characters into petscii or screencodes as desired (C64/Cx16)
 
-Rapid edit-compile-run-debug cycle:
+*Rapid edit-compile-run-debug cycle:*
 
-- use modern PC to work on 
+- use a modern PC to do the work on, use nice editors and enjoy quick compilation times
-- quick compilation times (seconds)
+- can automatically run the program in the Vice emulator after succesful compilation
-- option to automatically run the program in the Vice emulator  
 - breakpoints, that let the Vice emulator drop into the monitor if execution hits them
 - source code labels automatically loaded in Vice emulator so it can show them in disassembly
-- virtual machine that can execute compiled code directy on the host system,
-  without having to actually convert it to assembly to run on a real 6502 
 
-It is mainly targeted at the Commodore-64 machine at this time.
+*Multiple supported compiler targets* (contributions to improve these or to add support for other machines are welcome!):
-Contributions to add support for other 8-bit (or other?!) machines are welcome.
 
-Documentation/manual
+- "c64": Commodore-64  (6502 like CPU)
---------------------
+- "c128": Commodore-128  (6502 like CPU - the Z80 cpu mode is not supported)
-See https://prog8.readthedocs.io/
+- "cx16": [CommanderX16](https://www.commanderx16.com)  (65c02 CPU)
+- If you only use standard kernal and prog8 library routines, it is possible to compile the *exact same program* for different machines (just change the compiler target flag)
 
 
-Required tools
+
---------------
+Additional required tools
+-------------------------
 
 [64tass](https://sourceforge.net/projects/tass64/) - cross assembler. Install this on your shell path.
 A recent .exe version of this tool for Windows can be obtained from my [clone](https://github.com/irmen/64tass/releases) of this project.
 For other platforms it is very easy to compile it yourself (make ; make install).
 
-A **Java runtime (jre or jdk), version 8 or newer**  is required to run a prepackaged version of the compiler.
+A **Java runtime (jre or jdk), version 11 or newer**  is required to run a prepackaged version of the compiler.
 If you want to build it from source, you'll need a Java SDK + Kotlin 1.3.x SDK (or for instance,
 IntelliJ IDEA with the Kotlin plugin).
 
-It's handy to have a C-64 emulator or a real C-64 to run the programs on. The compiler assumes the presence
+It's handy to have an emulator (or a real machine perhaps!) to run the programs on. The compiler assumes the presence
-of the [Vice emulator](http://vice-emu.sourceforge.net/)
+of the [Vice emulator](http://vice-emu.sourceforge.net/)  for the C64 target,
+and the [x16emu emulator](https://github.com/commanderx16/x16-emulator) for the CommanderX16 target.
 
 
 Example code
@@ -66,44 +83,43 @@ Example code
 
 This code calculates prime numbers using the Sieve of Eratosthenes algorithm::
 
-    %import c64utils
+    %import textio
     %zeropage basicsafe
-
+    
     main {
-
+    
         ubyte[256] sieve
-        ubyte candidate_prime = 2
+        ubyte candidate_prime = 2       ; is increased in the loop
-
+    
         sub start() {
-            memset(sieve, 256, false)
+            sys.memset(sieve, 256, false)   ; clear the sieve
-
+            txt.print("prime numbers up to 255:\n\n")
-            c64scr.print("prime numbers up to 255:\n\n")
             ubyte amount=0
-            while true {
+            repeat {
                 ubyte prime = find_next_prime()
                 if prime==0
                     break
-                c64scr.print_ub(prime)
+                txt.print_ub(prime)
-                c64scr.print(", ")
+                txt.print(", ")
                 amount++
             }
-            c64.CHROUT('\n')
+            txt.nl()
-            c64scr.print("number of primes (expected 54): ")
+            txt.print("number of primes (expected 54): ")
-            c64scr.print_ub(amount)
+            txt.print_ub(amount)
-            c64.CHROUT('\n')
+            txt.nl()
         }
-
+    
-
         sub find_next_prime() -> ubyte {
-
             while sieve[candidate_prime] {
                 candidate_prime++
                 if candidate_prime==0
-                    return 0
+                    return 0        ; we wrapped; no more primes
             }
-
+    
+            ; found next one, mark the multiples and return it.
             sieve[candidate_prime] = true
             uword multiple = candidate_prime
+    
             while multiple < len(sieve) {
                 sieve[lsb(multiple)] = true
                 multiple += candidate_prime
@@ -113,11 +129,12 @@ This code calculates prime numbers using the Sieve of Eratosthenes algorithm::
     }
 
 
+
+
 when compiled an ran on a C-64 you'll get:
 
 ![c64 screen](docs/source/_static/primes_example.png)
 
-
 One of the included examples (wizzine.p8) animates a bunch of sprite balloons and looks like this:
 
 ![wizzine screen](docs/source/_static/wizzine.png)
@@ -129,3 +146,9 @@ Another example (cube3d-sprites.p8) draws the vertices of a rotating 3d cube:
 If you want to play a video game, a fully working Tetris clone is included in the examples:
 
 ![tehtriz_screen](docs/source/_static/tehtriz.png)
+
+There are a couple of examples specially made for the CommanderX16 compiler target.
+For instance here's a well known space ship animated in 3D with hidden line removal,
+in the CommanderX16 emulator:
+
+![cobra3d](docs/source/_static/cobra3d.png)

build.gradle

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

codeGeneration/build.gradle

@@ -0,0 +1,46 @@
+
+plugins {
+    id 'java'
+    id 'application'
+    id "org.jetbrains.kotlin.jvm"
+}
+
+java {
+    toolchain {
+        languageVersion = JavaLanguageVersion.of(javaVersion)
+    }
+}
+
+compileKotlin {
+    kotlinOptions {
+        jvmTarget = javaVersion
+    }
+}
+
+compileTestKotlin {
+    kotlinOptions {
+        jvmTarget = javaVersion
+    }
+}
+
+dependencies {
+    implementation project(':compilerInterfaces')
+    implementation project(':compilerAst')
+    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8"
+    // implementation "org.jetbrains.kotlin:kotlin-reflect"
+    implementation "com.michael-bull.kotlin-result:kotlin-result-jvm:1.1.12"
+
+}
+
+sourceSets {
+    main {
+        java {
+            srcDirs = ["${project.projectDir}/src"]
+        }
+        resources {
+            srcDirs = ["${project.projectDir}/res"]
+        }
+    }
+}
+
+// note: there are no unit tests in this module!

codeGeneration/codeGeneration.iml

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

codeGeneration/readme-tests.txt

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

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

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

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

@@ -0,0 +1,34 @@
+package prog8.codegen.target
+
+import prog8.ast.base.ByteDatatypes
+import prog8.ast.base.DataType
+import prog8.ast.base.PassByReferenceDatatypes
+import prog8.ast.base.WordDatatypes
+import prog8.ast.expressions.Expression
+import prog8.ast.statements.RegisterOrStatusflag
+import prog8.ast.statements.Subroutine
+import prog8.codegen.target.c128.C128MachineDefinition
+import prog8.codegen.target.cpu6502.codegen.asmsub6502ArgsEvalOrder
+import prog8.codegen.target.cpu6502.codegen.asmsub6502ArgsHaveRegisterClobberRisk
+import prog8.compilerinterface.ICompilationTarget
+import prog8.compilerinterface.IStringEncoding
+
+
+object C128Target: ICompilationTarget, IStringEncoding by Encoder {
+    override val name = "c128"
+    override val machine = C128MachineDefinition()
+
+    override fun asmsubArgsEvalOrder(sub: Subroutine): List<Int> =
+        asmsub6502ArgsEvalOrder(sub)
+    override fun asmsubArgsHaveRegisterClobberRisk(args: List<Expression>, paramRegisters: List<RegisterOrStatusflag>) =
+        asmsub6502ArgsHaveRegisterClobberRisk(args, paramRegisters)
+
+    override fun memorySize(dt: DataType): Int {
+        return when(dt) {
+            in ByteDatatypes -> 1
+            in WordDatatypes, in PassByReferenceDatatypes -> 2
+            DataType.FLOAT -> machine.FLOAT_MEM_SIZE
+            else -> Int.MIN_VALUE
+        }
+    }
+}

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

@@ -0,0 +1,34 @@
+package prog8.codegen.target
+
+import prog8.ast.base.ByteDatatypes
+import prog8.ast.base.DataType
+import prog8.ast.base.PassByReferenceDatatypes
+import prog8.ast.base.WordDatatypes
+import prog8.ast.expressions.Expression
+import prog8.ast.statements.RegisterOrStatusflag
+import prog8.ast.statements.Subroutine
+import prog8.codegen.target.c64.C64MachineDefinition
+import prog8.codegen.target.cpu6502.codegen.asmsub6502ArgsEvalOrder
+import prog8.codegen.target.cpu6502.codegen.asmsub6502ArgsHaveRegisterClobberRisk
+import prog8.compilerinterface.ICompilationTarget
+import prog8.compilerinterface.IStringEncoding
+
+
+object C64Target: ICompilationTarget, IStringEncoding by Encoder {
+    override val name = "c64"
+    override val machine = C64MachineDefinition()
+
+    override fun asmsubArgsEvalOrder(sub: Subroutine): List<Int> =
+        asmsub6502ArgsEvalOrder(sub)
+    override fun asmsubArgsHaveRegisterClobberRisk(args: List<Expression>, paramRegisters: List<RegisterOrStatusflag>) =
+        asmsub6502ArgsHaveRegisterClobberRisk(args, paramRegisters)
+
+    override fun memorySize(dt: DataType): Int {
+        return when(dt) {
+            in ByteDatatypes -> 1
+            in WordDatatypes, in PassByReferenceDatatypes -> 2
+            DataType.FLOAT -> machine.FLOAT_MEM_SIZE
+            else -> Int.MIN_VALUE
+        }
+    }
+}

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

@@ -0,0 +1,35 @@
+package prog8.codegen.target
+
+import prog8.ast.base.ByteDatatypes
+import prog8.ast.base.DataType
+import prog8.ast.base.PassByReferenceDatatypes
+import prog8.ast.base.WordDatatypes
+import prog8.ast.expressions.Expression
+import prog8.ast.statements.RegisterOrStatusflag
+import prog8.ast.statements.Subroutine
+import prog8.codegen.target.cpu6502.codegen.asmsub6502ArgsEvalOrder
+import prog8.codegen.target.cpu6502.codegen.asmsub6502ArgsHaveRegisterClobberRisk
+import prog8.codegen.target.cx16.CX16MachineDefinition
+import prog8.compilerinterface.ICompilationTarget
+import prog8.compilerinterface.IStringEncoding
+
+
+object Cx16Target: ICompilationTarget, IStringEncoding by Encoder {
+    override val name = "cx16"
+    override val machine = CX16MachineDefinition()
+
+    override fun asmsubArgsEvalOrder(sub: Subroutine): List<Int> =
+        asmsub6502ArgsEvalOrder(sub)
+    override fun asmsubArgsHaveRegisterClobberRisk(args: List<Expression>, paramRegisters: List<RegisterOrStatusflag>) =
+        asmsub6502ArgsHaveRegisterClobberRisk(args, paramRegisters)
+
+    override fun memorySize(dt: DataType): Int {
+        return when(dt) {
+            in ByteDatatypes -> 1
+            in WordDatatypes, in PassByReferenceDatatypes -> 2
+            DataType.FLOAT -> machine.FLOAT_MEM_SIZE
+            else -> Int.MIN_VALUE
+        }
+    }
+}
+

codeGeneration/src/prog8/codegen/target/Encoder.kt

@@ -0,0 +1,35 @@
+package prog8.codegen.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
+
+internal object Encoder: IStringEncoding {
+    override fun encodeString(str: String, encoding: Encoding): List<UByte> {              // TODO use Result
+        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")
+        }
+        return coded.fold(
+            failure = { throw it },
+            success = { it }
+        )
+    }
+    override fun decodeString(bytes: List<UByte>, encoding: Encoding): String {            // TODO use Result
+        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")
+        }
+        return decoded.fold(
+            failure = { throw it },
+            success = { it }
+        )
+    }
+}

codeGeneration/src/prog8/codegen/target/c128/C128MachineDefinition.kt

@@ -0,0 +1,67 @@
+package prog8.codegen.target.c128
+
+import prog8.ast.base.DataType
+import prog8.codegen.target.c64.normal6502instructions
+import prog8.codegen.target.cbm.Mflpt5
+import prog8.codegen.target.cbm.viceMonListName
+import prog8.compilerinterface.*
+import java.io.IOException
+import java.nio.file.Path
+
+
+class C128MachineDefinition: IMachineDefinition {
+
+    override val cpu = CpuType.CPU6502
+
+    override val FLOAT_MAX_POSITIVE = Mflpt5.FLOAT_MAX_POSITIVE
+    override val FLOAT_MAX_NEGATIVE = Mflpt5.FLOAT_MAX_NEGATIVE
+    override val FLOAT_MEM_SIZE = Mflpt5.FLOAT_MEM_SIZE
+    override val BASIC_LOAD_ADDRESS = 0x1c01u
+    override val RAW_LOAD_ADDRESS = 0x1300u
+
+    // the 2*256 byte evaluation stack (on which bytes, words, and even floats are stored during calculations)
+    override val ESTACK_LO = 0x1a00u     //  $1a00-$1aff inclusive
+    override val ESTACK_HI = 0x1b00u     //  $1b00-$1bff inclusive
+
+    override lateinit var zeropage: Zeropage
+
+    override fun getFloat(num: Number) = Mflpt5.fromNumber(num)
+
+    override fun importLibs(compilerOptions: CompilationOptions, compilationTargetName: String): List<String> {
+        return if (compilerOptions.launcher == LauncherType.BASIC || compilerOptions.output == OutputType.PRG)
+            listOf("syslib")
+        else
+            emptyList()
+    }
+
+    override fun launchEmulator(selectedEmulator: Int, programNameWithPath: Path) {
+        if(selectedEmulator!=1) {
+            System.err.println("The c128 target only supports the main emulator (Vice).")
+            return
+        }
+
+        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
+        }
+    }
+
+    override fun isIOAddress(address: UInt): Boolean = address==0u || address==1u || address in 0xd000u..0xdfffu
+
+    override fun initializeZeropage(compilerOptions: CompilationOptions) {
+        zeropage = C128Zeropage(compilerOptions)
+    }
+
+    override val opcodeNames = normal6502instructions
+}

codeGeneration/src/prog8/codegen/target/c128/C128Zeropage.kt

@@ -0,0 +1,42 @@
+package prog8.codegen.target.c128
+
+import prog8.compilerinterface.CompilationOptions
+import prog8.compilerinterface.InternalCompilerException
+import prog8.compilerinterface.Zeropage
+import prog8.compilerinterface.ZeropageType
+
+class C128Zeropage(options: CompilationOptions) : Zeropage(options) {
+
+    override val SCRATCH_B1 = 0x9bu      // temp storage for a single byte
+    override val SCRATCH_REG = 0x9cu     // temp storage for a register, must be B1+1
+    override val SCRATCH_W1 = 0xfbu      // temp storage 1 for a word  $fb+$fc
+    override val SCRATCH_W2 = 0xfdu      // temp storage 2 for a word  $fd+$fe
+
+
+    init {
+        if (options.floats && options.zeropage !in arrayOf(
+                ZeropageType.FLOATSAFE,
+                ZeropageType.BASICSAFE,
+                ZeropageType.DONTUSE
+            ))
+            throw InternalCompilerException("when floats are enabled, zero page type should be 'floatsafe' or 'basicsafe' or 'dontuse'")
+
+        when (options.zeropage) {
+            ZeropageType.FULL -> {
+                // TODO all c128 usable zero page locations, except the ones used by the system's IRQ routine
+                free.addAll(0x0au..0xffu)       // TODO c128 what about $02-$09?
+                // TODO c128  free.removeAll(setOf(0xa0u, 0xa1u, 0xa2u, 0x91u, 0xc0u, 0xc5u, 0xcbu, 0xf5u, 0xf6u))        // these are updated by IRQ
+            }
+            ZeropageType.KERNALSAFE,
+            ZeropageType.FLOATSAFE,
+            ZeropageType.BASICSAFE -> {
+                free.clear()   // TODO c128 usable zero page addresses
+            }
+            ZeropageType.DONTUSE -> {
+                free.clear()  // don't use zeropage at all
+            }
+        }
+
+        removeReservedFromFreePool()
+    }
+}

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

@@ -0,0 +1,79 @@
+package prog8.codegen.target.c64
+
+import prog8.ast.base.DataType
+import prog8.codegen.target.cbm.Mflpt5
+import prog8.codegen.target.cbm.viceMonListName
+import prog8.compilerinterface.*
+import java.io.IOException
+import java.nio.file.Path
+
+
+class C64MachineDefinition: IMachineDefinition {
+
+    override val cpu = CpuType.CPU6502
+
+    override val FLOAT_MAX_POSITIVE = Mflpt5.FLOAT_MAX_POSITIVE
+    override val FLOAT_MAX_NEGATIVE = Mflpt5.FLOAT_MAX_NEGATIVE
+    override val FLOAT_MEM_SIZE = Mflpt5.FLOAT_MEM_SIZE
+    override val BASIC_LOAD_ADDRESS = 0x0801u
+    override val RAW_LOAD_ADDRESS = 0xc000u
+
+    // the 2*256 byte evaluation stack (on which bytes, words, and even floats are stored during calculations)
+    override val ESTACK_LO = 0xce00u     //  $ce00-$ceff inclusive
+    override val ESTACK_HI = 0xcf00u     //  $ce00-$ceff inclusive
+
+    override lateinit var zeropage: Zeropage
+
+    override fun getFloat(num: Number) = Mflpt5.fromNumber(num)
+
+    override fun importLibs(compilerOptions: CompilationOptions, compilationTargetName: String): List<String> {
+        return if (compilerOptions.launcher == LauncherType.BASIC || compilerOptions.output == OutputType.PRG)
+            listOf("syslib")
+        else
+            emptyList()
+    }
+
+    override fun launchEmulator(selectedEmulator: Int, programNameWithPath: Path) {
+        if(selectedEmulator!=1) {
+            System.err.println("The c64 target only supports the main emulator (Vice).")
+            return
+        }
+
+        for(emulator in listOf("x64sc", "x64")) {
+            println("\nStarting C-64 emulator $emulator...")
+            val viceMonlist = viceMonListName(programNameWithPath.toString())
+            val cmdline = listOf(emulator, "-silent", "-moncommands", viceMonlist,
+                    "-autostartprgmode", "1", "-autostart-warp", "-autostart", "${programNameWithPath}.prg")
+            val processb = ProcessBuilder(cmdline).inheritIO()
+            val process: Process
+            try {
+                process=processb.start()
+            } catch(x: IOException) {
+                continue  // try the next emulator executable
+            }
+            process.waitFor()
+            break
+        }
+    }
+
+    override fun isIOAddress(address: UInt): Boolean = address==0u || address==1u || address in 0xd000u..0xdfffu
+
+    override fun initializeZeropage(compilerOptions: CompilationOptions) {
+        zeropage = C64Zeropage(compilerOptions)
+    }
+
+    override val opcodeNames = normal6502instructions
+}
+
+
+// 6502 opcodes (including aliases and illegal opcodes), these cannot be used as variable or label names
+internal val normal6502instructions = setOf(
+    "adc", "ahx", "alr", "anc", "and", "ane", "arr", "asl", "asr", "axs", "bcc", "bcs",
+    "beq", "bge", "bit", "blt", "bmi", "bne", "bpl", "brk", "bvc", "bvs", "clc",
+    "cld", "cli", "clv", "cmp", "cpx", "cpy", "dcm", "dcp", "dec", "dex", "dey",
+    "eor", "gcc", "gcs", "geq", "gge", "glt", "gmi", "gne", "gpl", "gvc", "gvs",
+    "inc", "ins", "inx", "iny", "isb", "isc", "jam", "jmp", "jsr", "lae", "las",
+    "lax", "lda", "lds", "ldx", "ldy", "lsr", "lxa", "nop", "ora", "pha", "php",
+    "pla", "plp", "rla", "rol", "ror", "rra", "rti", "rts", "sax", "sbc", "sbx",
+    "sec", "sed", "sei", "sha", "shl", "shr", "shs", "shx", "shy", "slo", "sre",
+    "sta", "stx", "sty", "tas", "tax", "tay", "tsx", "txa", "txs", "tya", "xaa")

codeGeneration/src/prog8/codegen/target/c64/C64Zeropage.kt

@@ -0,0 +1,73 @@
+package prog8.codegen.target.c64
+
+import prog8.compilerinterface.CompilationOptions
+import prog8.compilerinterface.InternalCompilerException
+import prog8.compilerinterface.Zeropage
+import prog8.compilerinterface.ZeropageType
+
+class C64Zeropage(options: CompilationOptions) : Zeropage(options) {
+
+    override val SCRATCH_B1 = 0x02u      // temp storage for a single byte
+    override val SCRATCH_REG = 0x03u     // temp storage for a register, must be B1+1
+    override val SCRATCH_W1 = 0xfbu      // temp storage 1 for a word  $fb+$fc
+    override val SCRATCH_W2 = 0xfdu      // temp storage 2 for a word  $fd+$fe
+
+
+    init {
+        if (options.floats && options.zeropage !in arrayOf(
+                ZeropageType.FLOATSAFE,
+                ZeropageType.BASICSAFE,
+                ZeropageType.DONTUSE
+            ))
+            throw InternalCompilerException("when floats are enabled, zero page type should be 'floatsafe' or 'basicsafe' or 'dontuse'")
+
+        if (options.zeropage == ZeropageType.FULL) {
+            free.addAll(0x02u..0xffu)
+            free.removeAll(setOf(SCRATCH_B1, SCRATCH_REG, SCRATCH_W1, SCRATCH_W1+1u, SCRATCH_W2, SCRATCH_W2+1u))
+            free.removeAll(setOf(0xa0u, 0xa1u, 0xa2u, 0x91u, 0xc0u, 0xc5u, 0xcbu, 0xf5u, 0xf6u))        // these are updated by IRQ
+        } else {
+            if (options.zeropage == ZeropageType.KERNALSAFE || options.zeropage == ZeropageType.FLOATSAFE) {
+                free.addAll(listOf(
+                        0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, 0x10, 0x11,
+                        0x16, 0x17, 0x18, 0x19, 0x1a,
+                        0x1b, 0x1c, 0x1d, 0x1e, 0x1f, 0x20, 0x21,
+                        0x22, 0x23, 0x24, 0x25,
+                        0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f, 0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46,
+                        0x47, 0x48, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f, 0x51, 0x52, 0x53,
+                        0x57, 0x58, 0x59, 0x5a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f, 0x60,
+                        0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68,
+                        0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f, 0x70, 0x71, 0x72,
+                        0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 0x7a, 0x7b, 0x7c,
+                        0x7d, 0x7e, 0x7f, 0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89, 0x8a,
+                        0x8b, 0x8c, 0x8d, 0x8e, 0x8f, 0xff
+                        // 0x90-0xfa is 'kernal work storage area'
+                ).map{it.toUInt()})
+            }
+
+            if (options.zeropage == ZeropageType.FLOATSAFE) {
+                // remove the zeropage locations used for floating point operations from the free list
+                free.removeAll(listOf(
+                        0x22, 0x23, 0x24, 0x25,
+                        0x10, 0x11, 0x12, 0x26, 0x27, 0x28, 0x29, 0x2a,
+                        0x57, 0x58, 0x59, 0x5a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f, 0x60,
+                        0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68,
+                        0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f, 0x70, 0x71, 0x72,
+                        0x8b, 0x8c, 0x8d, 0x8e, 0x8f, 0xff
+                ).map{it.toUInt()})
+            }
+
+            if(options.zeropage!= ZeropageType.DONTUSE) {
+                // add the free Zp addresses
+                // these are valid for the C-64 but allow BASIC to keep running fully *as long as you don't use tape I/O*
+                free.addAll(listOf(0x04, 0x05, 0x06, 0x0a, 0x0e,
+                        0x92, 0x96, 0x9b, 0x9c, 0x9e, 0x9f, 0xa5, 0xa6,
+                        0xb0, 0xb1, 0xbe, 0xbf, 0xf9).map{it.toUInt()})
+            } else {
+                // don't use the zeropage at all
+                free.clear()
+            }
+        }
+
+        removeReservedFromFreePool()
+    }
+}

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

@@ -0,0 +1,108 @@
+package prog8.codegen.target.cbm
+
+import com.github.michaelbull.result.Ok
+import com.github.michaelbull.result.Result
+import com.github.michaelbull.result.mapError
+import prog8.codegen.target.cpu6502.codegen.generatedLabelPrefix
+import prog8.compilerinterface.CompilationOptions
+import prog8.compilerinterface.IAssemblyProgram
+import prog8.compilerinterface.OutputType
+import prog8.parser.SourceCode
+import java.io.File
+import java.nio.file.Path
+import kotlin.io.path.Path
+import kotlin.io.path.isRegularFile
+
+
+internal fun viceMonListName(baseFilename: String) = "$baseFilename.vice-mon-list"
+
+class AssemblyProgram(
+        override val valid: Boolean,
+        override val name: String,
+        outputDir: Path,
+        private val compTarget: String) : IAssemblyProgram {
+
+    private val assemblyFile = outputDir.resolve("$name.asm")
+    private val prgFile = outputDir.resolve("$name.prg")
+    private val binFile = outputDir.resolve("$name.bin")
+    private val viceMonListFile = outputDir.resolve(viceMonListName(name))
+    private val listFile = outputDir.resolve("$name.list")
+
+    override fun assemble(options: CompilationOptions): Int {
+        // add "-Wlong-branch"  to see warnings about conversion of branch instructions to jumps (default = do this silently)
+        val command = mutableListOf("64tass", "--ascii", "--case-sensitive", "--long-branch",
+                "-Wall", "-Wno-strict-bool", "-Wno-shadow", // "-Werror",
+                "--dump-labels", "--vice-labels", "--labels=$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.")
+                prgFile
+            }
+            OutputType.RAW -> {
+                command.add("--nostart")
+                println("\nCreating raw binary for target $compTarget.")
+                binFile
+            }
+        }
+        command.addAll(listOf("--output", outFile.toString(), assemblyFile.toString()))
+
+        val proc = ProcessBuilder(command).inheritIO().start()
+        val result = proc.waitFor()
+        if (result == 0) {
+            removeGeneratedLabelsFromMonlist()
+            generateBreakpointList()
+        }
+        return result
+    }
+
+    private fun removeGeneratedLabelsFromMonlist() {
+        val pattern = Regex("""al (\w+) \S+${generatedLabelPrefix}.+?""")
+        val lines = viceMonListFile.toFile().readLines()
+        viceMonListFile.toFile().outputStream().bufferedWriter().use {
+            for (line in lines) {
+                if(pattern.matchEntire(line)==null)
+                    it.write(line+"\n")
+            }
+        }
+    }
+
+    private fun generateBreakpointList() {
+        // builds list of breakpoints, appends to monitor list file
+        val breakpoints = mutableListOf<String>()
+        val pattern = Regex("""al (\w+) \S+_prog8_breakpoint_\d+.?""")      // gather breakpoints by the source label that's generated for them
+        for (line in viceMonListFile.toFile().readLines()) {
+            val match = pattern.matchEntire(line)
+            if (match != null)
+                breakpoints.add("break \$" + match.groupValues[1])
+        }
+        val num = breakpoints.size
+        breakpoints.add(0, "; vice monitor breakpoint list now follows")
+        breakpoints.add(1, "; $num breakpoints have been defined")
+        breakpoints.add(2, "del")
+        viceMonListFile.toFile().appendText(breakpoints.joinToString("\n") + "\n")
+    }
+}
+
+
+internal fun loadAsmIncludeFile(filename: String, source: SourceCode): Result<String, NoSuchFileException> {
+    return if (filename.startsWith(SourceCode.libraryFilePrefix)) {
+        return com.github.michaelbull.result.runCatching {
+            SourceCode.Resource("/prog8lib/${filename.substring(SourceCode.libraryFilePrefix.length)}").readText()
+        }.mapError { NoSuchFileException(File(filename)) }
+    } else {
+        val sib = Path(source.origin).resolveSibling(filename)
+        if (sib.isRegularFile())
+            Ok(SourceCode.File(sib).readText())
+        else
+            Ok(SourceCode.File(Path(filename)).readText())
+    }
+}

codeGeneration/src/prog8/codegen/target/cbm/IsoEncoding.kt

@@ -0,0 +1,27 @@
+package prog8.codegen.target.cbm
+
+import com.github.michaelbull.result.Result
+import com.github.michaelbull.result.Ok
+import com.github.michaelbull.result.Err
+import java.io.CharConversionException
+import java.nio.charset.Charset
+
+object IsoEncoding {
+    val charset: Charset = Charset.forName("ISO-8859-15")
+
+    fun encode(str: String): Result<List<UByte>, CharConversionException> {
+        return try {
+            Ok(str.toByteArray(charset).map { it.toUByte() })
+        } catch (ce: CharConversionException) {
+            Err(ce)
+        }
+    }
+
+    fun decode(bytes: List<UByte>): Result<String, CharConversionException> {
+        return try {
+            Ok(String(bytes.map { it.toByte() }.toByteArray(), charset))
+        } catch (ce: CharConversionException) {
+            Err(ce)
+        }
+    }
+}

codeGeneration/src/prog8/codegen/target/cbm/Mflpt5.kt

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

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

@@ -0,0 +1,446 @@
+package prog8.codegen.target.cpu6502.codegen
+
+import prog8.ast.Program
+import prog8.ast.base.VarDeclType
+import prog8.ast.expressions.NumericLiteralValue
+import prog8.ast.statements.VarDecl
+import prog8.compilerinterface.IMachineDefinition
+
+
+// note: see https://wiki.nesdev.org/w/index.php/6502_assembly_optimisations
+
+
+fun optimizeAssembly(lines: MutableList<String>, machine: IMachineDefinition, program: Program): Int {
+
+    var numberOfOptimizations = 0
+
+    var linesByFour = getLinesBy(lines, 4)
+
+    var mods = optimizeUselessStackByteWrites(linesByFour)
+    if(mods.isNotEmpty()) {
+        apply(mods, lines)
+        linesByFour = getLinesBy(lines, 4)
+        numberOfOptimizations++
+    }
+
+    mods = optimizeIncDec(linesByFour)
+    if(mods.isNotEmpty()) {
+        apply(mods, lines)
+        linesByFour = getLinesBy(lines, 4)
+        numberOfOptimizations++
+    }
+
+    mods = optimizeCmpSequence(linesByFour)
+    if(mods.isNotEmpty()) {
+        apply(mods, lines)
+        linesByFour = getLinesBy(lines, 4)
+        numberOfOptimizations++
+    }
+
+    mods = optimizeStoreLoadSame(linesByFour, machine, program)
+    if(mods.isNotEmpty()) {
+        apply(mods, lines)
+        linesByFour = getLinesBy(lines, 4)
+        numberOfOptimizations++
+    }
+
+    mods= optimizeJsrRts(linesByFour)
+    if(mods.isNotEmpty()) {
+        apply(mods, lines)
+        linesByFour = getLinesBy(lines, 4)
+        numberOfOptimizations++
+    }
+
+    var linesByFourteen = getLinesBy(lines, 14)
+    mods = optimizeSameAssignments(linesByFourteen, machine, program)
+    if(mods.isNotEmpty()) {
+        apply(mods, lines)
+        linesByFourteen = getLinesBy(lines, 14)
+        numberOfOptimizations++
+    }
+
+    // TODO more assembly optimizations
+
+    return numberOfOptimizations
+}
+
+private class Modification(val lineIndex: Int, val remove: Boolean, val replacement: String?)
+
+private fun apply(modifications: List<Modification>, lines: MutableList<String>) {
+    for (modification in modifications.sortedBy { it.lineIndex }.reversed()) {
+        if(modification.remove)
+            lines.removeAt(modification.lineIndex)
+        else
+            lines[modification.lineIndex] = modification.replacement!!
+    }
+}
+
+private fun getLinesBy(lines: MutableList<String>, windowSize: Int) =
+// all lines (that aren't empty or comments) in sliding windows of certain size
+        lines.withIndex().filter { it.value.isNotBlank() && !it.value.trimStart().startsWith(';') }.windowed(windowSize, partialWindows = false)
+
+private fun optimizeCmpSequence(linesByFour: List<List<IndexedValue<String>>>): List<Modification> {
+    // when statement (on bytes) generates a sequence of:
+    //	 lda  $ce01,x
+    //	 cmp  #$20
+    //	 beq  check_prog8_s72choice_32
+    //	 lda  $ce01,x
+    //	 cmp  #$21
+    //	 beq  check_prog8_s73choice_33
+    // the repeated lda can be removed
+    val mods = mutableListOf<Modification>()
+    for(lines in linesByFour) {
+        if(lines[0].value.trim()=="lda  P8ESTACK_LO+1,x" &&
+                lines[1].value.trim().startsWith("cmp ") &&
+                lines[2].value.trim().startsWith("beq ") &&
+                lines[3].value.trim()=="lda  P8ESTACK_LO+1,x") {
+            mods.add(Modification(lines[3].index, true, null)) // remove the second lda
+        }
+    }
+    return mods
+}
+
+private fun optimizeUselessStackByteWrites(linesByFour: List<List<IndexedValue<String>>>): List<Modification> {
+    // sta on stack, dex, inx, lda from stack -> eliminate this useless stack byte write
+    // this is a lot harder for word values because the instruction sequence varies.
+    val mods = mutableListOf<Modification>()
+    for(lines in linesByFour) {
+        if(lines[0].value.trim()=="sta  P8ESTACK_LO,x" &&
+                lines[1].value.trim()=="dex" &&
+                lines[2].value.trim()=="inx" &&
+                lines[3].value.trim()=="lda  P8ESTACK_LO,x") {
+            mods.add(Modification(lines[1].index, true, null))
+            mods.add(Modification(lines[2].index, true, null))
+            mods.add(Modification(lines[3].index, true, null))
+        }
+    }
+    return mods
+}
+
+private fun optimizeSameAssignments(linesByFourteen: List<List<IndexedValue<String>>>, machine: IMachineDefinition, program: Program): List<Modification> {
+
+    // Optimize sequential assignments of the same value to various targets (bytes, words, floats)
+    // the float one is the one that requires 2*7=14 lines of code to check...
+    // The better place to do this is in the Compiler instead and never create these types of assembly, but hey
+
+    val mods = mutableListOf<Modification>()
+    for (lines in linesByFourteen) {
+        val first = lines[0].value.trimStart()
+        val second = lines[1].value.trimStart()
+        val third = lines[2].value.trimStart()
+        val fourth = lines[3].value.trimStart()
+        val fifth = lines[4].value.trimStart()
+        val sixth = lines[5].value.trimStart()
+        val seventh = lines[6].value.trimStart()
+        val eighth = lines[7].value.trimStart()
+
+        if(first.startsWith("lda") && second.startsWith("ldy") && third.startsWith("sta") && fourth.startsWith("sty") &&
+                fifth.startsWith("lda") && sixth.startsWith("ldy") && seventh.startsWith("sta") && eighth.startsWith("sty")) {
+            val firstvalue = first.substring(4)
+            val secondvalue = second.substring(4)
+            val thirdvalue = fifth.substring(4)
+            val fourthvalue = sixth.substring(4)
+            if(firstvalue==thirdvalue && secondvalue==fourthvalue) {
+                // lda/ldy   sta/sty   twice the same word -->  remove second lda/ldy pair (fifth and sixth lines)
+                val address1 = getAddressArg(first, program)
+                val address2 = getAddressArg(second, program)
+                if(address1==null || address2==null || (!machine.isIOAddress(address1) && !machine.isIOAddress(address2))) {
+                    mods.add(Modification(lines[4].index, true, null))
+                    mods.add(Modification(lines[5].index, true, null))
+                }
+            }
+        }
+
+        if(first.startsWith("lda") && second.startsWith("sta") && third.startsWith("lda") && fourth.startsWith("sta")) {
+            val firstvalue = first.substring(4)
+            val secondvalue = third.substring(4)
+            if(firstvalue==secondvalue) {
+                // lda value / sta ? / lda same-value / sta ?  -> remove second lda (third line)
+                val address = getAddressArg(first, program)
+                if(address==null || !machine.isIOAddress(address))
+                    mods.add(Modification(lines[2].index, true, null))
+            }
+        }
+
+        if(first.startsWith("lda") && second.startsWith("ldy") && third.startsWith("sta") && fourth.startsWith("sty") &&
+                fifth.startsWith("lda") && sixth.startsWith("ldy") &&
+                (seventh.startsWith("jsr  floats.copy_float") || seventh.startsWith("jsr  cx16flt.copy_float"))) {
+
+            val nineth = lines[8].value.trimStart()
+            val tenth = lines[9].value.trimStart()
+            val eleventh = lines[10].value.trimStart()
+            val twelveth = lines[11].value.trimStart()
+            val thirteenth = lines[12].value.trimStart()
+            val fourteenth = lines[13].value.trimStart()
+
+            if(eighth.startsWith("lda") && nineth.startsWith("ldy") && tenth.startsWith("sta") && eleventh.startsWith("sty") &&
+                    twelveth.startsWith("lda") && thirteenth.startsWith("ldy") &&
+                    (fourteenth.startsWith("jsr  floats.copy_float") || fourteenth.startsWith("jsr  cx16flt.copy_float"))) {
+
+                if(first.substring(4) == eighth.substring(4) && second.substring(4)==nineth.substring(4)) {
+                    // identical float init
+                    mods.add(Modification(lines[7].index, true, null))
+                    mods.add(Modification(lines[8].index, true, null))
+                    mods.add(Modification(lines[9].index, true, null))
+                    mods.add(Modification(lines[10].index, true, null))
+                }
+            }
+        }
+
+        var overlappingMods = false
+        /*
+        sta  prog8_lib.retval_intermX      ; remove
+        sty  prog8_lib.retval_intermY      ; remove
+        lda  prog8_lib.retval_intermX      ; remove
+        ldy  prog8_lib.retval_intermY      ; remove
+        sta  A1
+        sty  A2
+         */
+        if(first.startsWith("st") && second.startsWith("st")
+            && third.startsWith("ld") && fourth.startsWith("ld")
+            && fifth.startsWith("st") && sixth.startsWith("st")) {
+            val reg1 = first[2]
+            val reg2 = second[2]
+            val reg3 = third[2]
+            val reg4 = fourth[2]
+            val reg5 = fifth[2]
+            val reg6 = sixth[2]
+            if (reg1 == reg3 && reg1 == reg5 && reg2 == reg4 && reg2 == reg6) {
+                val firstvalue = first.substring(4)
+                val secondvalue = second.substring(4)
+                val thirdvalue = third.substring(4)
+                val fourthvalue = fourth.substring(4)
+                if(firstvalue.contains("prog8_lib.retval_interm") && secondvalue.contains("prog8_lib.retval_interm")
+                    && firstvalue==thirdvalue && secondvalue==fourthvalue) {
+                    mods.add(Modification(lines[0].index, true, null))
+                    mods.add(Modification(lines[1].index, true, null))
+                    mods.add(Modification(lines[2].index, true, null))
+                    mods.add(Modification(lines[3].index, true, null))
+                    overlappingMods = true
+                }
+            }
+        }
+
+        /*
+        sta  A1
+        sty  A2
+        lda  A1     ; can be removed
+        ldy  A2     ; can be removed if not followed by a branch instuction
+         */
+        if(!overlappingMods && first.startsWith("st") && second.startsWith("st")
+            && third.startsWith("ld") && fourth.startsWith("ld")) {
+            val reg1 = first[2]
+            val reg2 = second[2]
+            val reg3 = third[2]
+            val reg4 = fourth[2]
+            if(reg1==reg3 && reg2==reg4) {
+                val firstvalue = first.substring(4)
+                val secondvalue = second.substring(4)
+                val thirdvalue = third.substring(4)
+                val fourthvalue = fourth.substring(4)
+                if(firstvalue==thirdvalue && secondvalue == fourthvalue) {
+                    val address = getAddressArg(first, program)
+                    if(address==null || !machine.isIOAddress(address)) {
+                        overlappingMods = true
+                        mods.add(Modification(lines[2].index, true, null))
+                        if (!fifth.startsWith('b'))
+                            mods.add(Modification(lines[3].index, true, null))
+                    }
+                }
+            }
+        }
+        /*
+        sta  A1
+        sty  A2
+        lda  A1     ; can be removed if not followed by a branch instruction
+         */
+        if(!overlappingMods && first.startsWith("st") && second.startsWith("st")
+            && third.startsWith("ld") && !fourth.startsWith("b")) {
+            val reg1 = first[2]
+            val reg3 = third[2]
+            if(reg1==reg3) {
+                val firstvalue = first.substring(4)
+                val thirdvalue = third.substring(4)
+                if(firstvalue==thirdvalue) {
+                    val address = getAddressArg(first, program)
+                    if(address==null || !machine.isIOAddress(address)) {
+                        overlappingMods = true
+                        mods.add(Modification(lines[2].index, true, null))
+                    }
+                }
+            }
+        }
+
+        /*
+        sta  A1
+        ldy  A1     ; make tay
+        sta  A1     ; remove
+         */
+        if(!overlappingMods && first.startsWith("sta") && second.startsWith("ld")
+            && third.startsWith("sta") && second.length>4) {
+            val firstvalue = first.substring(4)
+            val secondvalue = second.substring(4)
+            val thirdvalue = third.substring(4)
+            if(firstvalue==secondvalue && firstvalue==thirdvalue) {
+                val address = getAddressArg(first, program)
+                if(address==null || !machine.isIOAddress(address)) {
+                    overlappingMods = true
+                    val reg2 = second[2]
+                    mods.add(Modification(lines[1].index, false, "  ta$reg2"))
+                    mods.add(Modification(lines[2].index, true, null))
+                }
+            }
+        }
+
+        /*
+        sta  A
+        sta  A
+         */
+        if(!overlappingMods && first.startsWith("st") && second.startsWith("st")) {
+            if(first[2]==second[2]) {
+                val firstvalue = first.substring(4)
+                val secondvalue = second.substring(4)
+                if(firstvalue==secondvalue) {
+                    val address = getAddressArg(first, program)
+                    if(address==null || !machine.isIOAddress(address)) {
+                        overlappingMods = true
+                        mods.add(Modification(lines[1].index, true, null))
+                    }
+                }
+            }
+        }
+    }
+
+    return mods
+}
+
+private fun optimizeStoreLoadSame(linesByFour: List<List<IndexedValue<String>>>, machine: IMachineDefinition, program: Program): List<Modification> {
+    // sta X + lda X,  sty X + ldy X,   stx X + ldx X  -> the second instruction can OFTEN be eliminated
+    val mods = mutableListOf<Modification>()
+    for (lines in linesByFour) {
+        val first = lines[1].value.trimStart()
+        val second = lines[2].value.trimStart()
+
+        if ((first.startsWith("sta ") && second.startsWith("lda ")) ||
+                (first.startsWith("stx ") && second.startsWith("ldx ")) ||
+                (first.startsWith("sty ") && second.startsWith("ldy ")) ||
+                (first.startsWith("lda ") && second.startsWith("lda ")) ||
+                (first.startsWith("ldy ") && second.startsWith("ldy ")) ||
+                (first.startsWith("ldx ") && second.startsWith("ldx ")) ||
+                (first.startsWith("sta ") && second.startsWith("lda ")) ||
+                (first.startsWith("sty ") && second.startsWith("ldy ")) ||
+                (first.startsWith("stx ") && second.startsWith("ldx "))
+        ) {
+            val third = lines[3].value.trimStart()
+            val attemptRemove =
+                if(third.startsWith("b")) {
+                    // a branch instruction follows, we can only remove the load instruction if
+                    // another load instruction of the same register precedes the store instruction
+                    // (otherwise wrong cpu flags are used)
+                    val loadinstruction = second.substring(0, 3)
+                    lines[0].value.trimStart().startsWith(loadinstruction)
+                }
+                else {
+                    // no branch instruction follows, we can remove the load instruction
+                    val address = getAddressArg(lines[2].value, program)
+                    address==null || !machine.isIOAddress(address)
+                }
+
+            if(attemptRemove) {
+                val firstLoc = first.substring(4).trimStart()
+                val secondLoc = second.substring(4).trimStart()
+                if (firstLoc == secondLoc)
+                    mods.add(Modification(lines[2].index, true, null))
+            }
+        }
+        else if(first=="pha" && second=="pla" ||
+            first=="phx" && second=="plx" ||
+            first=="phy" && second=="ply" ||
+            first=="php" && second=="plp") {
+            mods.add(Modification(lines[1].index, true, null))
+            mods.add(Modification(lines[2].index, true, null))
+        } else if(first=="pha" && second=="plx") {
+            mods.add(Modification(lines[1].index, true, null))
+            mods.add(Modification(lines[2].index, false, "  tax"))
+        } else if(first=="pha" && second=="ply") {
+            mods.add(Modification(lines[1].index, true, null))
+            mods.add(Modification(lines[2].index, false, "  tay"))
+        } else if(first=="phx" && second=="pla") {
+            mods.add(Modification(lines[1].index, true, null))
+            mods.add(Modification(lines[2].index, false, "  txa"))
+        } else if(first=="phx" && second=="ply") {
+            mods.add(Modification(lines[1].index, true, null))
+            mods.add(Modification(lines[2].index, false, "  txy"))
+        } else if(first=="phy" && second=="pla") {
+            mods.add(Modification(lines[1].index, true, null))
+            mods.add(Modification(lines[2].index, false, "  tya"))
+        } else if(first=="phy" && second=="plx") {
+            mods.add(Modification(lines[1].index, true, null))
+            mods.add(Modification(lines[2].index, false, "  tyx"))
+        }
+    }
+    return mods
+}
+
+private val identifierRegex = Regex("""^([a-zA-Z_$][a-zA-Z\d_\.$]*)""")
+
+private fun getAddressArg(line: String, program: Program): UInt? {
+    val loadArg = line.trimStart().substring(3).trim()
+    return when {
+        loadArg.startsWith('$') -> loadArg.substring(1).toUIntOrNull(16)
+        loadArg.startsWith('%') -> loadArg.substring(1).toUIntOrNull(2)
+        loadArg.startsWith('#') -> null
+        loadArg.startsWith('(') -> null
+        loadArg[0].isLetter() -> {
+            val identMatch = identifierRegex.find(loadArg)
+            if(identMatch!=null) {
+                val identifier = identMatch.value
+                val decl = program.toplevelModule.lookup(identifier.split(".")) as? VarDecl
+                if(decl!=null) {
+                    when(decl.type){
+                        VarDeclType.VAR -> null
+                        VarDeclType.CONST,
+                        VarDeclType.MEMORY -> (decl.value as NumericLiteralValue).number.toUInt()
+                    }
+                }
+                else null
+            } else null
+        }
+        else -> loadArg.substring(1).toUIntOrNull()
+    }
+}
+
+private fun optimizeIncDec(linesByFour: List<List<IndexedValue<String>>>): List<Modification> {
+    // sometimes, iny+dey / inx+dex / dey+iny / dex+inx sequences are generated, these can be eliminated.
+    val mods = mutableListOf<Modification>()
+    for (lines in linesByFour) {
+        val first = lines[0].value
+        val second = lines[1].value
+        if ((" iny" in first || "\tiny" in first) && (" dey" in second || "\tdey" in second)
+                || (" inx" in first || "\tinx" in first) && (" dex" in second || "\tdex" in second)
+                || (" ina" in first || "\tina" in first) && (" dea" in second || "\tdea" in second)
+                || (" inc  a" in first || "\tinc  a" in first) && (" dec  a" in second || "\tdec  a" in second)
+                || (" dey" in first || "\tdey" in first) && (" iny" in second || "\tiny" in second)
+                || (" dex" in first || "\tdex" in first) && (" inx" in second || "\tinx" in second)
+                || (" dea" in first || "\tdea" in first) && (" ina" in second || "\tina" in second)
+                || (" dec  a" in first || "\tdec  a" in first) && (" inc  a" in second || "\tinc  a" in second)) {
+            mods.add(Modification(lines[0].index, true, null))
+            mods.add(Modification(lines[1].index, true, null))
+        }
+    }
+    return mods
+}
+
+private fun optimizeJsrRts(linesByFour: List<List<IndexedValue<String>>>): List<Modification> {
+    // jsr Sub + rts -> jmp Sub
+    val mods = mutableListOf<Modification>()
+    for (lines in linesByFour) {
+        val first = lines[0].value
+        val second = lines[1].value
+        if ((" jsr" in first || "\tjsr" in first ) && (" rts" in second || "\trts" in second)) {
+            mods += Modification(lines[0].index, false, lines[0].value.replace("jsr", "jmp"))
+            mods += Modification(lines[1].index, true, null)
+        }
+    }
+    return mods
+}

codeGeneration/src/prog8/codegen/target/cpu6502/codegen/AsmsubHelpers.kt

@@ -0,0 +1,59 @@
+package prog8.codegen.target.cpu6502.codegen
+
+import prog8.ast.base.Cx16VirtualRegisters
+import prog8.ast.base.RegisterOrPair
+import prog8.ast.expressions.*
+import prog8.ast.statements.RegisterOrStatusflag
+import prog8.ast.statements.Subroutine
+
+
+internal fun asmsub6502ArgsEvalOrder(sub: Subroutine): List<Int> {
+    val order = mutableListOf<Int>()
+    // order is:
+    //  1) cx16 virtual word registers,
+    //  2) paired CPU registers,
+    //  3) single CPU registers (X last), except A,
+    //  4) CPU Carry status flag
+    //  5) the A register itself last   (so everything before it can use the accumulator without having to save its value)
+    val args = sub.parameters.zip(sub.asmParameterRegisters).withIndex()
+    val (cx16regs, args2) = args.partition { it.value.second.registerOrPair in Cx16VirtualRegisters }
+    val pairedRegisters = arrayOf(RegisterOrPair.AX, RegisterOrPair.AY, RegisterOrPair.XY)
+    val (pairedRegs , args3) = args2.partition { it.value.second.registerOrPair in pairedRegisters }
+    val (regsWithoutA, args4) = args3.partition { it.value.second.registerOrPair != RegisterOrPair.A }
+    val (regA, rest) = args4.partition { it.value.second.registerOrPair != null }
+
+    cx16regs.forEach { order += it.index }
+    pairedRegs.forEach { order += it.index }
+    regsWithoutA.forEach {
+        if(it.value.second.registerOrPair != RegisterOrPair.X)
+            order += it.index
+    }
+    regsWithoutA.firstOrNull { it.value.second.registerOrPair==RegisterOrPair.X } ?.let { order += it.index}
+    rest.forEach { order += it.index }
+    regA.forEach { order += it.index }
+    require(order.size==sub.parameters.size)
+    return order
+}
+
+internal fun asmsub6502ArgsHaveRegisterClobberRisk(args: List<Expression>,
+                                                   paramRegisters: List<RegisterOrStatusflag>): Boolean {
+    fun isClobberRisk(expr: Expression): Boolean {
+        when (expr) {
+            is ArrayIndexedExpression -> {
+                return paramRegisters.any {
+                    it.registerOrPair in listOf(RegisterOrPair.Y, RegisterOrPair.AY, RegisterOrPair.XY)
+                }
+            }
+            is FunctionCallExpression -> {
+                if (expr.target.nameInSource == listOf("lsb") || expr.target.nameInSource == listOf("msb"))
+                    return isClobberRisk(expr.args[0])
+                if (expr.target.nameInSource == listOf("mkword"))
+                    return isClobberRisk(expr.args[0]) && isClobberRisk(expr.args[1])
+                return !expr.isSimple
+            }
+            else -> return !expr.isSimple
+        }
+    }
+
+    return args.size>1 && args.any { isClobberRisk(it) }
+}

codeGeneration/src/prog8/codegen/target/cpu6502/codegen/ExpressionsAsmGen.kt

@@ -0,0 +1,863 @@
+package prog8.codegen.target.cpu6502.codegen
+
+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.codegen.target.AssemblyError
+import prog8.compilerinterface.BuiltinFunctions
+import prog8.compilerinterface.CpuType
+import kotlin.math.absoluteValue
+
+internal class ExpressionsAsmGen(private val program: Program, private val asmgen: AsmGen, private val functioncallAsmGen: FunctionCallAsmGen) {
+
+    @Deprecated("avoid calling this as it generates slow evalstack based code")
+    internal fun translateExpression(expression:Expression) {
+        if (this.asmgen.options.slowCodegenWarnings) {
+            asmgen.errors.warn("slow stack evaluation used for expression $expression", expression.position)
+        }
+        translateExpressionInternal(expression)
+    }
+
+
+    // the rest of the methods are all PRIVATE
+
+
+    private fun translateExpressionInternal(expression: Expression) {
+
+        when(expression) {
+            is PrefixExpression -> translateExpression(expression)
+            is BinaryExpression -> translateExpression(expression)
+            is ArrayIndexedExpression -> translateExpression(expression)
+            is TypecastExpression -> translateExpression(expression)
+            is AddressOf -> translateExpression(expression)
+            is DirectMemoryRead -> asmgen.translateDirectMemReadExpressionToRegAorStack(expression, true)
+            is NumericLiteralValue -> translateExpression(expression)
+            is IdentifierReference -> translateExpression(expression)
+            is FunctionCallExpression -> translateFunctionCallResultOntoStack(expression)
+            is PipeExpression -> asmgen.translatePipeExpression(expression.expressions,  expression,false, true)
+            is ContainmentCheck -> throw AssemblyError("containment check as complex expression value is not supported")
+            is ArrayLiteralValue, is StringLiteralValue -> throw AssemblyError("no asm gen for string/array literal value assignment - should have been replaced by a variable")
+            is RangeExpression -> throw AssemblyError("range expression should have been changed into array values")
+            is CharLiteral -> throw AssemblyError("charliteral should have been replaced by ubyte using certain encoding")
+            else -> TODO("missing expression asmgen for $expression")
+        }
+    }
+
+    private fun translateFunctionCallResultOntoStack(call: FunctionCallExpression) {
+        // only for use in nested expression evaluation
+
+        val sub = call.target.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 returns = sub.returntypes.zip(sub.asmReturnvaluesRegisters)
+            for ((_, reg) in returns) {
+                // result value is in cpu or status registers, put it on the stack instead (as we're evaluating an expression tree)
+                if (reg.registerOrPair != null) {
+                    when (reg.registerOrPair!!) {
+                        RegisterOrPair.A -> asmgen.out("  sta  P8ESTACK_LO,x |  dex")
+                        RegisterOrPair.Y -> asmgen.out("  tya |  sta  P8ESTACK_LO,x |  dex")
+                        RegisterOrPair.AY -> asmgen.out("  sta  P8ESTACK_LO,x |  tya |  sta  P8ESTACK_HI,x |  dex")
+                        RegisterOrPair.X -> asmgen.out("  lda  P8ZP_SCRATCH_REG |  sta  P8ESTACK_LO,x |  dex")
+                        RegisterOrPair.AX -> asmgen.out("  sta  P8ESTACK_LO,x |  lda  P8ZP_SCRATCH_REG |  sta  P8ESTACK_HI,x |  dex")
+                        RegisterOrPair.XY -> asmgen.out("  tya |  sta  P8ESTACK_HI,x |  lda  P8ZP_SCRATCH_REG |  sta  P8ESTACK_LO,x |  dex")
+                        RegisterOrPair.FAC1 -> asmgen.out("  jsr  floats.push_fac1")
+                        RegisterOrPair.FAC2 -> asmgen.out("  jsr  floats.push_fac2")
+                        RegisterOrPair.R0,
+                        RegisterOrPair.R1,
+                        RegisterOrPair.R2,
+                        RegisterOrPair.R3,
+                        RegisterOrPair.R4,
+                        RegisterOrPair.R5,
+                        RegisterOrPair.R6,
+                        RegisterOrPair.R7,
+                        RegisterOrPair.R8,
+                        RegisterOrPair.R9,
+                        RegisterOrPair.R10,
+                        RegisterOrPair.R11,
+                        RegisterOrPair.R12,
+                        RegisterOrPair.R13,
+                        RegisterOrPair.R14,
+                        RegisterOrPair.R15 -> {
+                            asmgen.out(
+                                """
+                                lda  cx16.${reg.registerOrPair.toString().lowercase()}
+                                sta  P8ESTACK_LO,x
+                                lda  cx16.${reg.registerOrPair.toString().lowercase()}+1
+                                sta  P8ESTACK_HI,x
+                                dex
+                            """)
+                        }
+                    }
+                } else when(reg.statusflag) {
+                    Statusflag.Pc -> {
+                        asmgen.out("""
+                            lda  #0
+                            rol  a
+                            sta  P8ESTACK_LO,x
+                            dex""")
+                    }
+                    Statusflag.Pz -> {
+                        asmgen.out("""
+                            beq  +
+                            lda  #0
+                            beq  ++
++                           lda  #1
++                           sta  P8ESTACK_LO,x
+                            dex""")
+                    }
+                    Statusflag.Pv -> {
+                        asmgen.out("""
+                            bvs  +
+                            lda  #0
+                            beq  ++
++                           lda  #1
++                           sta  P8ESTACK_LO,x
+                            dex""")
+                    }
+                    Statusflag.Pn -> {
+                        asmgen.out("""
+                            bmi  +
+                            lda  #0
+                            beq  ++
++                           lda  #1
++                           sta  P8ESTACK_LO,x
+                            dex""")
+                    }
+                    null -> {}
+                }
+            }
+        }
+    }
+
+    private fun translateExpression(typecast: TypecastExpression) {
+        translateExpressionInternal(typecast.expression)
+        when(typecast.expression.inferType(program).getOr(DataType.UNDEFINED)) {
+            DataType.UBYTE -> {
+                when(typecast.type) {
+                    DataType.UBYTE, DataType.BYTE -> {}
+                    DataType.UWORD, DataType.WORD -> {
+                        if(asmgen.isTargetCpu(CpuType.CPU65c02))
+                            asmgen.out("  stz  P8ESTACK_HI+1,x")
+                        else
+                            asmgen.out("  lda  #0  |  sta  P8ESTACK_HI+1,x")
+                    }
+                    DataType.FLOAT -> asmgen.out(" jsr  floats.stack_ub2float")
+                    in PassByReferenceDatatypes -> throw AssemblyError("cannot cast to a pass-by-reference datatype")
+                    else -> throw AssemblyError("weird type")
+                }
+            }
+            DataType.BYTE -> {
+                when(typecast.type) {
+                    DataType.UBYTE, DataType.BYTE -> {}
+                    DataType.UWORD, DataType.WORD -> asmgen.signExtendStackLsb(DataType.BYTE)
+                    DataType.FLOAT -> asmgen.out(" jsr  floats.stack_b2float")
+                    in PassByReferenceDatatypes -> throw AssemblyError("cannot cast to a pass-by-reference datatype")
+                    else -> throw AssemblyError("weird type")
+                }
+            }
+            DataType.UWORD -> {
+                when(typecast.type) {
+                    DataType.BYTE, DataType.UBYTE -> {}
+                    DataType.WORD, DataType.UWORD -> {}
+                    DataType.FLOAT -> asmgen.out(" jsr  floats.stack_uw2float")
+                    in PassByReferenceDatatypes -> throw AssemblyError("cannot cast to a pass-by-reference datatype")
+                    else -> throw AssemblyError("weird type")
+                }
+            }
+            DataType.WORD -> {
+                when(typecast.type) {
+                    DataType.BYTE, DataType.UBYTE -> {}
+                    DataType.WORD, DataType.UWORD -> {}
+                    DataType.FLOAT -> asmgen.out(" jsr  floats.stack_w2float")
+                    in PassByReferenceDatatypes -> throw AssemblyError("cannot cast to a pass-by-reference datatype")
+                    else -> throw AssemblyError("weird type")
+                }
+            }
+            DataType.FLOAT -> {
+                when(typecast.type) {
+                    DataType.UBYTE -> asmgen.out(" jsr  floats.stack_float2uw")
+                    DataType.BYTE -> asmgen.out(" jsr  floats.stack_float2w")
+                    DataType.UWORD -> asmgen.out(" jsr  floats.stack_float2uw")
+                    DataType.WORD -> asmgen.out(" jsr  floats.stack_float2w")
+                    DataType.FLOAT -> {}
+                    in PassByReferenceDatatypes -> throw AssemblyError("cannot cast to a pass-by-reference datatype")
+                    else -> throw AssemblyError("weird type")
+                }
+            }
+            DataType.STR -> {
+                if (typecast.type != DataType.UWORD && typecast.type == DataType.STR)
+                    throw AssemblyError("cannot typecast a string into another incompatitble type")
+            }
+            in PassByReferenceDatatypes -> throw AssemblyError("cannot cast pass-by-reference value into another type")
+            else -> throw AssemblyError("weird type")
+        }
+    }
+
+    private fun translateExpression(expr: AddressOf) {
+        val name = asmgen.asmVariableName(expr.identifier)
+        asmgen.out("  lda  #<$name |  sta  P8ESTACK_LO,x |  lda  #>$name  |  sta  P8ESTACK_HI,x  | dex")
+    }
+
+    private fun translateExpression(expr: NumericLiteralValue) {
+        when(expr.type) {
+            DataType.UBYTE, DataType.BYTE -> asmgen.out(" lda  #${expr.number.toHex()}  | sta  P8ESTACK_LO,x  | dex")
+            DataType.UWORD, DataType.WORD -> asmgen.out("""
+                lda  #<${expr.number.toHex()}
+                sta  P8ESTACK_LO,x
+                lda  #>${expr.number.toHex()}
+                sta  P8ESTACK_HI,x
+                dex
+            """)
+            DataType.FLOAT -> {
+                val floatConst = asmgen.getFloatAsmConst(expr.number)
+                asmgen.out(" lda  #<$floatConst |  ldy  #>$floatConst |  jsr  floats.push_float")
+            }
+            else -> throw AssemblyError("weird type")
+        }
+    }
+
+    private fun translateExpression(expr: IdentifierReference) {
+        val varname = asmgen.asmVariableName(expr)
+        when(expr.inferType(program).getOr(DataType.UNDEFINED)) {
+            DataType.UBYTE, DataType.BYTE -> {
+                asmgen.out("  lda  $varname  |  sta  P8ESTACK_LO,x  |  dex")
+            }
+            DataType.UWORD, DataType.WORD -> {
+                asmgen.out("  lda  $varname  |  sta  P8ESTACK_LO,x  |  lda  $varname+1 |  sta  P8ESTACK_HI,x |  dex")
+            }
+            DataType.FLOAT -> {
+                asmgen.out(" lda  #<$varname |  ldy  #>$varname|  jsr  floats.push_float")
+            }
+            in IterableDatatypes -> {
+                asmgen.out("  lda  #<$varname  |  sta  P8ESTACK_LO,x  |  lda  #>$varname |  sta  P8ESTACK_HI,x |  dex")
+            }
+            else -> throw AssemblyError("stack push weird variable type $expr")
+        }
+    }
+
+    private fun translateExpression(expr: BinaryExpression) {
+        // Uses evalstack to evaluate the given expression.
+        // TODO we're slowly reducing the number of places where this is called and instead replace that by more efficient assignment-form code (using temp var or register for instance).
+        val leftIDt = expr.left.inferType(program)
+        val rightIDt = expr.right.inferType(program)
+        if(!leftIDt.isKnown || !rightIDt.isKnown)
+            throw AssemblyError("can't infer type of both expression operands")
+
+        val leftDt = leftIDt.getOrElse { throw AssemblyError("unknown dt") }
+        val rightDt = rightIDt.getOrElse { throw AssemblyError("unknown dt") }
+        // see if we can apply some optimized routines
+        when(expr.operator) {
+            "+" -> {
+                if(leftDt in IntegerDatatypes && rightDt in IntegerDatatypes) {
+                    val leftVal = expr.left.constValue(program)?.number?.toInt()
+                    val rightVal = expr.right.constValue(program)?.number?.toInt()
+                    if (leftVal!=null && leftVal in -4..4) {
+                        translateExpressionInternal(expr.right)
+                        if(rightDt in ByteDatatypes) {
+                            val incdec = if(leftVal<0) "dec" else "inc"
+                            repeat(leftVal.absoluteValue) {
+                                asmgen.out("  $incdec  P8ESTACK_LO+1,x")
+                            }
+                        } else {
+                            // word
+                            if(leftVal<0) {
+                                repeat(leftVal.absoluteValue) {
+                                    asmgen.out("""
+                                        lda  P8ESTACK_LO+1,x
+                                        bne  +
+                                        dec  P8ESTACK_HI+1,x
++                                       dec  P8ESTACK_LO+1,x""")
+                                }
+                            } else {
+                                repeat(leftVal) {
+                                    asmgen.out("""
+                                        inc  P8ESTACK_LO+1,x
+                                        bne  +
+                                        inc  P8ESTACK_HI+1,x
++""")
+                                }
+                            }
+                        }
+                        return
+                    }
+                    else if (rightVal!=null && rightVal in -4..4)
+                    {
+                        translateExpressionInternal(expr.left)
+                        if(leftDt in ByteDatatypes) {
+                            val incdec = if(rightVal<0) "dec" else "inc"
+                            repeat(rightVal.absoluteValue) {
+                                asmgen.out("  $incdec  P8ESTACK_LO+1,x")
+                            }
+                        } else {
+                            // word
+                            if(rightVal<0) {
+                                repeat(rightVal.absoluteValue) {
+                                    asmgen.out("""
+                                        lda  P8ESTACK_LO+1,x
+                                        bne  +
+                                        dec  P8ESTACK_HI+1,x
++                                       dec  P8ESTACK_LO+1,x""")
+                                }
+                            } else {
+                                repeat(rightVal) {
+                                    asmgen.out("""
+                                        inc  P8ESTACK_LO+1,x
+                                        bne  +
+                                        inc  P8ESTACK_HI+1,x
++""")
+                                }
+                            }
+                        }
+                        return
+                    }
+                }
+            }
+            "-" -> {
+                if(leftDt in IntegerDatatypes && rightDt in IntegerDatatypes) {
+                    val rightVal = expr.right.constValue(program)?.number?.toInt()
+                    if (rightVal!=null && rightVal in -4..4)
+                    {
+                        translateExpressionInternal(expr.left)
+                        if(leftDt in ByteDatatypes) {
+                            val incdec = if(rightVal<0) "inc" else "dec"
+                            repeat(rightVal.absoluteValue) {
+                                asmgen.out("  $incdec  P8ESTACK_LO+1,x")
+                            }
+                        } else {
+                            // word
+                            if(rightVal>0) {
+                                repeat(rightVal.absoluteValue) {
+                                    asmgen.out("""
+                                        lda  P8ESTACK_LO+1,x
+                                        bne  +
+                                        dec  P8ESTACK_HI+1,x
++                                       dec  P8ESTACK_LO+1,x""")
+                                }
+                            } else {
+                                repeat(rightVal) {
+                                    asmgen.out("""
+                                        inc  P8ESTACK_LO+1,x
+                                        bne  +
+                                        inc  P8ESTACK_HI+1,x
++""")
+                                }
+                            }
+                        }
+                        return
+                    }
+                }
+            }
+            ">>" -> {
+                val amount = expr.right.constValue(program)?.number?.toInt()
+                if(amount!=null) {
+                    translateExpressionInternal(expr.left)
+                    when (leftDt) {
+                        DataType.UBYTE -> {
+                            if (amount <= 2)
+                                repeat(amount) { asmgen.out(" lsr  P8ESTACK_LO+1,x") }
+                            else {
+                                asmgen.out(" lda  P8ESTACK_LO+1,x")
+                                repeat(amount) { asmgen.out(" lsr  a") }
+                                asmgen.out(" sta  P8ESTACK_LO+1,x")
+                            }
+                        }
+                        DataType.BYTE -> {
+                            if (amount <= 2)
+                                repeat(amount) { asmgen.out(" lda  P8ESTACK_LO+1,x |  asl  a |  ror  P8ESTACK_LO+1,x") }
+                            else {
+                                asmgen.out(" lda  P8ESTACK_LO+1,x |  sta  P8ZP_SCRATCH_B1")
+                                repeat(amount) { asmgen.out(" asl  a |  ror  P8ZP_SCRATCH_B1 |  lda  P8ZP_SCRATCH_B1") }
+                                asmgen.out(" sta  P8ESTACK_LO+1,x")
+                            }
+                        }
+                        DataType.UWORD -> {
+                            if(amount>=16) {
+                                if(asmgen.isTargetCpu(CpuType.CPU65c02))
+                                    asmgen.out("  stz  P8ESTACK_LO+1,x |  stz  P8ESTACK_HI+1,x")
+                                else
+                                    asmgen.out("  lda  #0 |  sta  P8ESTACK_LO+1,x |  sta  P8ESTACK_HI+1,x")
+                                return
+                            }
+                            var left = amount
+                            while (left >= 7) {
+                                asmgen.out(" jsr  math.shift_right_uw_7")
+                                left -= 7
+                            }
+                            if (left in 0..2)
+                                repeat(left) { asmgen.out(" lsr  P8ESTACK_HI+1,x |  ror  P8ESTACK_LO+1,x") }
+                            else
+                                asmgen.out(" jsr  math.shift_right_uw_$left")
+                        }
+                        DataType.WORD -> {
+                            if(amount>=16) {
+                                asmgen.out("""
+                                    lda  P8ESTACK_HI+1,x
+                                    bmi  +
+                                    lda  #0
+                                    sta  P8ESTACK_LO+1,x
+                                    sta  P8ESTACK_HI+1,x
+                                    beq  ++
++                                   lda  #255
+                                    sta  P8ESTACK_LO+1,x
+                                    sta  P8ESTACK_HI+1,x
++""")
+                                return
+                            }
+                            var left = amount
+                            while (left >= 7) {
+                                asmgen.out(" jsr  math.shift_right_w_7")
+                                left -= 7
+                            }
+                            if (left in 0..2)
+                                repeat(left) { asmgen.out(" lda  P8ESTACK_HI+1,x |  asl  a  |  ror  P8ESTACK_HI+1,x |  ror  P8ESTACK_LO+1,x") }
+                            else
+                                asmgen.out(" jsr  math.shift_right_w_$left")
+                        }
+                        else -> throw AssemblyError("weird type")
+                    }
+                    return
+                }
+            }
+            "<<" -> {
+                val amount = expr.right.constValue(program)?.number?.toInt()
+                if(amount!=null) {
+                    translateExpressionInternal(expr.left)
+                    if (leftDt in ByteDatatypes) {
+                        if (amount <= 2)
+                            repeat(amount) { asmgen.out("  asl  P8ESTACK_LO+1,x") }
+                        else {
+                            asmgen.out("  lda  P8ESTACK_LO+1,x")
+                            repeat(amount) { asmgen.out("  asl  a") }
+                            asmgen.out("  sta  P8ESTACK_LO+1,x")
+                        }
+                    } else {
+                        var left = amount
+                        while (left >= 7) {
+                            asmgen.out(" jsr  math.shift_left_w_7")
+                            left -= 7
+                        }
+                        if (left in 0..2)
+                            repeat(left) { asmgen.out("  asl  P8ESTACK_LO+1,x |  rol  P8ESTACK_HI+1,x") }
+                        else
+                            asmgen.out(" jsr  math.shift_left_w_$left")
+                    }
+                    return
+                }
+            }
+            "*" -> {
+                if(leftDt in IntegerDatatypes && rightDt in IntegerDatatypes) {
+                    val leftVar = expr.left as? IdentifierReference
+                    val rightVar = expr.right as? IdentifierReference
+                    if(leftVar!=null && rightVar!=null && leftVar==rightVar)
+                        return translateSquared(leftVar, leftDt)
+                }
+
+                val value = expr.right.constValue(program)
+                if(value!=null) {
+                    if(rightDt in IntegerDatatypes) {
+                        val amount = value.number.toInt()
+                        if(amount==2) {
+                            // optimize x*2 common case
+                            translateExpressionInternal(expr.left)
+                            if(leftDt in ByteDatatypes) {
+                                asmgen.out("  asl  P8ESTACK_LO+1,x")
+                            } else {
+                                asmgen.out("  asl  P8ESTACK_LO+1,x |  rol  P8ESTACK_HI+1,x")
+                            }
+                            return
+                        }
+                        when(rightDt) {
+                            DataType.UBYTE -> {
+                                if(amount in asmgen.optimizedByteMultiplications) {
+                                    translateExpressionInternal(expr.left)
+                                    asmgen.out(" jsr  math.stack_mul_byte_$amount")
+                                    return
+                                }
+                            }
+                            DataType.BYTE -> {
+                                if(amount in asmgen.optimizedByteMultiplications) {
+                                    translateExpressionInternal(expr.left)
+                                    asmgen.out(" jsr  math.stack_mul_byte_$amount")
+                                    return
+                                }
+                                if(amount.absoluteValue in asmgen.optimizedByteMultiplications) {
+                                    translateExpressionInternal(expr.left)
+                                    asmgen.out(" jsr  prog8_lib.neg_b |  jsr  math.stack_mul_byte_${amount.absoluteValue}")
+                                    return
+                                }
+                            }
+                            DataType.UWORD -> {
+                                if(amount in asmgen.optimizedWordMultiplications) {
+                                    translateExpressionInternal(expr.left)
+                                    asmgen.out(" jsr  math.stack_mul_word_$amount")
+                                    return
+                                }
+                            }
+                            DataType.WORD -> {
+                                if(amount in asmgen.optimizedWordMultiplications) {
+                                    translateExpressionInternal(expr.left)
+                                    asmgen.out(" jsr  math.stack_mul_word_$amount")
+                                    return
+                                }
+                                if(amount.absoluteValue in asmgen.optimizedWordMultiplications) {
+                                    translateExpressionInternal(expr.left)
+                                    asmgen.out(" jsr  prog8_lib.neg_w |  jsr  math.stack_mul_word_${amount.absoluteValue}")
+                                    return
+                                }
+                            }
+                            else -> {}
+                        }
+                    }
+                }
+            }
+            "/" -> {
+                if(leftDt in IntegerDatatypes && rightDt in IntegerDatatypes) {
+                    val rightVal = expr.right.constValue(program)?.number?.toInt()
+                    if(rightVal!=null && rightVal==2) {
+                        translateExpressionInternal(expr.left)
+                        when(leftDt) {
+                            DataType.UBYTE -> asmgen.out("  lsr  P8ESTACK_LO+1,x")
+                            DataType.BYTE -> asmgen.out("  lda  P8ESTACK_LO+1,x |  asl  a |  ror  P8ESTACK_LO+1,x")
+                            DataType.UWORD -> asmgen.out("  lsr  P8ESTACK_HI+1,x |  ror  P8ESTACK_LO+1,x")
+                            DataType.WORD -> asmgen.out("  lda  P8ESTACK_HI+1,x |  asl  a |  ror  P8ESTACK_HI+1,x |  ror  P8ESTACK_LO+1,x")
+                            else -> throw AssemblyError("wrong dt")
+                        }
+                        return
+                    }
+                }
+            }
+            in ComparisonOperators -> {
+                if(leftDt in NumericDatatypes && rightDt in NumericDatatypes) {
+                    val rightVal = expr.right.constValue(program)?.number?.toInt()
+                    if(rightVal==0)
+                        return translateComparisonWithZero(expr.left, leftDt, expr.operator)
+                }
+            }
+        }
+
+        if((leftDt in ByteDatatypes && rightDt !in ByteDatatypes)
+                || (leftDt in WordDatatypes && rightDt !in WordDatatypes))
+            throw AssemblyError("binary operator ${expr.operator} left/right dt not identical")
+
+        if(leftDt==DataType.STR && rightDt==DataType.STR && expr.operator in ComparisonOperators) {
+            translateCompareStrings(expr.left, expr.operator, expr.right)
+        }
+        else {
+            // the general, non-optimized cases  TODO optimize more cases.... (or one day just don't use the evalstack at all anymore)
+            translateExpressionInternal(expr.left)
+            translateExpressionInternal(expr.right)
+            when (leftDt) {
+                in ByteDatatypes -> translateBinaryOperatorBytes(expr.operator, leftDt)
+                in WordDatatypes -> translateBinaryOperatorWords(expr.operator, leftDt)
+                DataType.FLOAT -> translateBinaryOperatorFloats(expr.operator)
+                else -> throw AssemblyError("non-numerical datatype")
+            }
+        }
+    }
+
+    private fun translateComparisonWithZero(expr: Expression, dt: DataType, operator: String) {
+        translateExpressionInternal(expr)
+        when(operator) {
+            "==" -> {
+                when(dt) {
+                    DataType.UBYTE, DataType.BYTE -> asmgen.out("  jsr  prog8_lib.equalzero_b")
+                    DataType.UWORD, DataType.WORD -> asmgen.out("  jsr  prog8_lib.equalzero_w")
+                    DataType.FLOAT -> asmgen.out("  jsr  floats.equal_zero")
+                    else -> throw AssemblyError("wrong dt")
+                }
+            }
+            "!=" -> {
+                when(dt) {
+                    DataType.UBYTE, DataType.BYTE -> asmgen.out("  jsr  prog8_lib.notequalzero_b")
+                    DataType.UWORD, DataType.WORD -> asmgen.out("  jsr  prog8_lib.notequalzero_w")
+                    DataType.FLOAT -> asmgen.out("  jsr  floats.notequal_zero")
+                    else -> throw AssemblyError("wrong dt")
+                }
+            }
+            "<" -> {
+                if(dt==DataType.UBYTE || dt==DataType.UWORD)
+                    return translateExpressionInternal(NumericLiteralValue.fromBoolean(false, expr.position))
+                when(dt) {
+                    DataType.BYTE -> asmgen.out("  jsr  prog8_lib.lesszero_b")
+                    DataType.WORD -> asmgen.out("  jsr  prog8_lib.lesszero_w")
+                    DataType.FLOAT -> asmgen.out("  jsr  floats.less_zero")
+                    else -> throw AssemblyError("wrong dt")
+                }
+            }
+            ">" -> {
+                when(dt) {
+                    DataType.UBYTE -> asmgen.out("  jsr  prog8_lib.greaterzero_ub")
+                    DataType.BYTE -> asmgen.out("  jsr  prog8_lib.greaterzero_sb")
+                    DataType.UWORD -> asmgen.out("  jsr  prog8_lib.greaterzero_uw")
+                    DataType.WORD -> asmgen.out("  jsr  prog8_lib.greaterzero_sw")
+                    DataType.FLOAT -> asmgen.out("  jsr  floats.greater_zero")
+                    else -> throw AssemblyError("wrong dt")
+                }
+            }
+            "<=" -> {
+                when(dt) {
+                    DataType.UBYTE -> asmgen.out("  jsr  prog8_lib.equalzero_b")
+                    DataType.BYTE -> asmgen.out("  jsr  prog8_lib.lessequalzeros_b")
+                    DataType.UWORD -> asmgen.out("  jsr  prog8_lib.equalzero_w")
+                    DataType.WORD -> asmgen.out("  jsr  prog8_lib.lessequalzero_sw")
+                    DataType.FLOAT -> asmgen.out("  jsr  floats.lessequal_zero")
+                    else -> throw AssemblyError("wrong dt")
+                }
+            }
+            ">=" -> {
+                if(dt==DataType.UBYTE || dt==DataType.UWORD)
+                    return translateExpressionInternal(NumericLiteralValue.fromBoolean(true, expr.position))
+                when(dt) {
+                    DataType.BYTE -> asmgen.out("  jsr  prog8_lib.greaterequalzero_sb")
+                    DataType.WORD -> asmgen.out("  jsr  prog8_lib.greaterequalzero_sw")
+                    DataType.FLOAT -> asmgen.out("  jsr  floats.greaterequal_zero")
+                    else -> throw AssemblyError("wrong dt")
+                }
+            }
+            else -> throw AssemblyError("invalid comparison operator")
+        }
+    }
+
+    private fun translateSquared(variable: IdentifierReference, dt: DataType) {
+        val asmVar = asmgen.asmVariableName(variable)
+        when(dt) {
+            DataType.BYTE, DataType.UBYTE -> {
+                asmgen.out("  lda  $asmVar")
+                asmgen.signExtendAYlsb(dt)
+                asmgen.out("  jsr  math.square")
+            }
+            DataType.UWORD, DataType.WORD -> {
+                asmgen.out("  lda  $asmVar |  ldy  $asmVar+1 |  jsr  math.square")
+            }
+            else -> throw AssemblyError("require integer dt for square")
+        }
+        asmgen.out("  sta  P8ESTACK_LO,x |  tya |  sta  P8ESTACK_HI,x |  dex")
+    }
+
+    private fun translateExpression(expr: PrefixExpression) {
+        translateExpressionInternal(expr.expression)
+        val itype = expr.inferType(program)
+        val type = itype.getOrElse { throw AssemblyError("unknown dt") }
+        when(expr.operator) {
+            "+" -> {}
+            "-" -> {
+                when(type) {
+                    in ByteDatatypes -> asmgen.out("  jsr  prog8_lib.neg_b")
+                    in WordDatatypes -> asmgen.out("  jsr  prog8_lib.neg_w")
+                    DataType.FLOAT -> asmgen.out("  jsr  floats.neg_f")
+                    else -> throw AssemblyError("weird type")
+                }
+            }
+            "~" -> {
+                when(type) {
+                    in ByteDatatypes ->
+                        asmgen.out("""
+                            lda  P8ESTACK_LO+1,x
+                            eor  #255
+                            sta  P8ESTACK_LO+1,x
+                            """)
+                    in WordDatatypes -> asmgen.out("  jsr  prog8_lib.inv_word")
+                    else -> throw AssemblyError("weird type")
+                }
+            }
+            "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}")
+        }
+    }
+
+    private fun translateExpression(arrayExpr: ArrayIndexedExpression) {
+        val elementIDt = arrayExpr.inferType(program)
+        if(!elementIDt.isKnown)
+            throw AssemblyError("unknown dt")
+        val elementDt = elementIDt.getOr(DataType.UNDEFINED)
+        val arrayVarName = asmgen.asmVariableName(arrayExpr.arrayvar)
+        val constIndexNum = arrayExpr.indexer.constIndex()
+        if(constIndexNum!=null) {
+            val indexValue = constIndexNum * program.memsizer.memorySize(elementDt)
+            when(elementDt) {
+                in ByteDatatypes -> {
+                    asmgen.out("  lda  $arrayVarName+$indexValue |  sta  P8ESTACK_LO,x |  dex")
+                }
+                in WordDatatypes -> {
+                    asmgen.out("  lda  $arrayVarName+$indexValue |  sta  P8ESTACK_LO,x |  lda  $arrayVarName+$indexValue+1 |  sta  P8ESTACK_HI,x |  dex")
+                }
+                DataType.FLOAT -> {
+                    asmgen.out("  lda  #<($arrayVarName+$indexValue) |  ldy  #>($arrayVarName+$indexValue) |  jsr  floats.push_float")
+                }
+                else -> throw AssemblyError("weird element type")
+            }
+        } else {
+            when(elementDt) {
+                in ByteDatatypes -> {
+                    asmgen.loadScaledArrayIndexIntoRegister(arrayExpr, elementDt, CpuRegister.Y)
+                    asmgen.out(" lda  $arrayVarName,y |  sta  P8ESTACK_LO,x |  dex")
+                }
+                in WordDatatypes -> {
+                    asmgen.loadScaledArrayIndexIntoRegister(arrayExpr, elementDt, CpuRegister.Y)
+                    asmgen.out(" lda  $arrayVarName,y |  sta  P8ESTACK_LO,x |  lda  $arrayVarName+1,y |  sta  P8ESTACK_HI,x |  dex")
+                }
+                DataType.FLOAT -> {
+                    asmgen.loadScaledArrayIndexIntoRegister(arrayExpr, elementDt, CpuRegister.A)
+                    asmgen.out("""
+                        ldy  #>$arrayVarName
+                        clc
+                        adc  #<$arrayVarName
+                        bcc  +
+                        iny
++                       jsr  floats.push_float""")
+                }
+                else -> throw AssemblyError("weird dt")
+            }
+
+        }
+    }
+
+    private fun translateBinaryOperatorBytes(operator: String, types: DataType) {
+        when(operator) {
+            "**" -> 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")
+            "%" -> {
+                if(types==DataType.BYTE)
+                    throw AssemblyError("remainder of signed integers is not properly defined/implemented, use unsigned instead")
+                asmgen.out("  jsr prog8_lib.remainder_ub")
+            }
+            "+" -> asmgen.out("""
+                lda  P8ESTACK_LO+2,x
+                clc
+                adc  P8ESTACK_LO+1,x
+                inx
+                sta  P8ESTACK_LO+1,x
+                """)
+            "-" -> asmgen.out("""
+                lda  P8ESTACK_LO+2,x
+                sec
+                sbc  P8ESTACK_LO+1,x
+                inx
+                sta  P8ESTACK_LO+1,x
+                """)
+            "<<" -> asmgen.out("  jsr  prog8_lib.shiftleft_b")
+            ">>" -> asmgen.out("  jsr  prog8_lib.shiftright_b")
+            "<" -> asmgen.out(if(types==DataType.UBYTE) "  jsr  prog8_lib.less_ub" else "  jsr  prog8_lib.less_b")
+            ">" -> asmgen.out(if(types==DataType.UBYTE) "  jsr  prog8_lib.greater_ub" else "  jsr  prog8_lib.greater_b")
+            "<=" -> asmgen.out(if(types==DataType.UBYTE) "  jsr  prog8_lib.lesseq_ub" else "  jsr  prog8_lib.lesseq_b")
+            ">=" -> asmgen.out(if(types==DataType.UBYTE) "  jsr  prog8_lib.greatereq_ub" else "  jsr  prog8_lib.greatereq_b")
+            "==" -> asmgen.out("  jsr  prog8_lib.equal_b")
+            "!=" -> asmgen.out("  jsr  prog8_lib.notequal_b")
+            "&" -> asmgen.out("  jsr  prog8_lib.bitand_b")
+            "^" -> asmgen.out("  jsr  prog8_lib.bitxor_b")
+            "|" -> asmgen.out("  jsr  prog8_lib.bitor_b")
+            "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")
+            "%" -> {
+                if(dt==DataType.WORD)
+                    throw AssemblyError("remainder of signed integers is not properly defined/implemented, use unsigned instead")
+                asmgen.out("  jsr prog8_lib.remainder_uw")
+            }
+            "+" -> asmgen.out("  jsr  prog8_lib.add_w")
+            "-" -> asmgen.out("  jsr  prog8_lib.sub_w")
+            "<<" -> asmgen.out("  jsr  math.shift_left_w")
+            ">>" -> {
+                if(dt==DataType.UWORD)
+                    asmgen.out("  jsr  math.shift_right_uw")
+                else
+                    asmgen.out("  jsr  math.shift_right_w")
+            }
+            "<" -> asmgen.out(if(dt==DataType.UWORD) "  jsr  prog8_lib.less_uw" else "  jsr  prog8_lib.less_w")
+            ">" -> asmgen.out(if(dt==DataType.UWORD) "  jsr  prog8_lib.greater_uw" else "  jsr  prog8_lib.greater_w")
+            "<=" -> asmgen.out(if(dt==DataType.UWORD) "  jsr  prog8_lib.lesseq_uw" else "  jsr  prog8_lib.lesseq_w")
+            ">=" -> asmgen.out(if(dt==DataType.UWORD) "  jsr  prog8_lib.greatereq_uw" else "  jsr  prog8_lib.greatereq_w")
+            "==" -> asmgen.out("  jsr  prog8_lib.equal_w")
+            "!=" -> asmgen.out("  jsr  prog8_lib.notequal_w")            "&" -> asmgen.out("  jsr  prog8_lib.bitand_w")
+            "^" -> asmgen.out("  jsr  prog8_lib.bitxor_w")
+            "|" -> asmgen.out("  jsr  prog8_lib.bitor_w")
+            "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")
+            "-" -> asmgen.out("  jsr  floats.sub_f")
+            "<" -> asmgen.out("  jsr  floats.less_f")
+            ">" -> asmgen.out("  jsr  floats.greater_f")
+            "<=" -> asmgen.out("  jsr  floats.lesseq_f")
+            ">=" -> asmgen.out("  jsr  floats.greatereq_f")
+            "==" -> asmgen.out("  jsr  floats.equal_f")
+            "!=" -> asmgen.out("  jsr  floats.notequal_f")
+            "%", "<<", ">>", "&", "^", "|", "and", "or", "xor" -> throw AssemblyError("requires integer datatype")
+            else -> throw AssemblyError("invalid operator $operator")
+        }
+    }
+
+    private fun translateCompareStrings(s1: Expression, operator: String, s2: Expression) {
+        asmgen.assignExpressionToVariable(s1, "prog8_lib.strcmp_expression._arg_s1", DataType.UWORD, null)
+        asmgen.assignExpressionToVariable(s2, "prog8_lib.strcmp_expression._arg_s2", DataType.UWORD, null)
+        asmgen.out(" jsr  prog8_lib.strcmp_expression")    // result  of compare is in A
+        when(operator) {
+            "==" -> asmgen.out(" and  #1 |  eor  #1 |  sta  P8ESTACK_LO,x")
+            "!=" -> asmgen.out(" and  #1 |  sta  P8ESTACK_LO,x")
+            "<=" -> asmgen.out("""
+                bpl  +
+                lda  #1
+                bne  ++
++               lda  #0
++               sta  P8ESTACK_LO,x""")
+            ">=" -> asmgen.out("""
+                bmi  +
+                lda  #1
+                bne  ++
++               lda  #0
++               sta  P8ESTACK_LO,x""")
+            "<" -> asmgen.out("""
+                bmi  +
+                lda  #0
+                beq  ++
++               lda  #1
++               sta  P8ESTACK_LO,x""")
+            ">" -> asmgen.out("""
+                bpl  +
+                lda  #0
+                beq  ++
++               lda  #1
++               sta  P8ESTACK_LO,x""")
+        }
+        asmgen.out("  dex")
+    }
+}

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

@@ -0,0 +1,601 @@
+package prog8.codegen.target.cpu6502.codegen
+
+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.codegen.target.AssemblyError
+import kotlin.math.absoluteValue
+
+internal class ForLoopsAsmGen(private val program: Program, private val asmgen: AsmGen) {
+
+    internal fun translate(stmt: ForLoop) {
+        val iterableDt = stmt.iterable.inferType(program)
+        if(!iterableDt.isKnown)
+            throw AssemblyError("unknown dt")
+        when(stmt.iterable) {
+            is RangeExpression -> {
+                val range = (stmt.iterable as RangeExpression).toConstantIntegerRange()
+                if(range==null) {
+                    translateForOverNonconstRange(stmt, iterableDt.getOrElse { throw AssemblyError("unknown dt") }, stmt.iterable as RangeExpression)
+                } else {
+                    translateForOverConstRange(stmt, iterableDt.getOrElse { throw AssemblyError("unknown dt") }, range)
+                }
+            }
+            is IdentifierReference -> {
+                translateForOverIterableVar(stmt, iterableDt.getOrElse { throw AssemblyError("unknown dt") }, stmt.iterable as IdentifierReference)
+            }
+            else -> throw AssemblyError("can't iterate over ${stmt.iterable.javaClass} - should have been replaced by a variable")
+        }
+    }
+
+    private fun translateForOverNonconstRange(stmt: ForLoop, iterableDt: DataType, range: RangeExpression) {
+        val loopLabel = asmgen.makeLabel("for_loop")
+        val endLabel = asmgen.makeLabel("for_end")
+        val modifiedLabel = asmgen.makeLabel("for_modified")
+        val modifiedLabel2 = asmgen.makeLabel("for_modifiedb")
+        asmgen.loopEndLabels.push(endLabel)
+        val stepsize=range.step.constValue(program)!!.number.toInt()
+
+        if(stepsize < -1) {
+            val limit = range.to.constValue(program)?.number
+            if(limit==0.0)
+                throw AssemblyError("for unsigned loop variable it's not possible to count down with step != -1 from a non-const value to exactly zero due to value wrapping")
+        }
+
+        when(iterableDt) {
+            DataType.ARRAY_B, DataType.ARRAY_UB -> {
+                if (stepsize==1 || stepsize==-1) {
+
+                    // bytes array, step 1 or -1
+
+                    val incdec = if(stepsize==1) "inc" else "dec"
+                    // loop over byte range via loopvar
+                    val varname = asmgen.asmVariableName(stmt.loopVar)
+                    asmgen.assignExpressionToVariable(range.from, varname, ArrayToElementTypes.getValue(iterableDt), null)
+                    asmgen.assignExpressionToVariable(range.to, "$modifiedLabel+1", ArrayToElementTypes.getValue(iterableDt), null)
+                    asmgen.out(loopLabel)
+                    asmgen.translate(stmt.body)
+                    asmgen.out("""
+                        lda  $varname
+$modifiedLabel          cmp  #0         ; modified 
+                        beq  $endLabel
+                        $incdec  $varname""")
+                    asmgen.jmp(loopLabel)
+                    asmgen.out(endLabel)
+
+                } else {
+
+                    // bytes, step >= 2 or <= -2
+
+                    // loop over byte range via loopvar
+                    val varname = asmgen.asmVariableName(stmt.loopVar)
+                    asmgen.assignExpressionToVariable(range.from, varname, ArrayToElementTypes.getValue(iterableDt), null)
+                    asmgen.assignExpressionToVariable(range.to, "$modifiedLabel+1", ArrayToElementTypes.getValue(iterableDt), null)
+                    asmgen.out(loopLabel)
+                    asmgen.translate(stmt.body)
+                    if(stepsize>0) {
+                        asmgen.out("""
+                            lda  $varname
+                            clc
+                            adc  #$stepsize
+                            sta  $varname
+$modifiedLabel              cmp  #0    ; modified
+                            bmi  $loopLabel
+                            beq  $loopLabel""")
+                    } else {
+                        asmgen.out("""
+                            lda  $varname
+                            sec
+                            sbc  #${stepsize.absoluteValue}
+                            sta  $varname
+$modifiedLabel              cmp  #0     ; modified
+                            bpl  $loopLabel""")
+                    }
+                    asmgen.out(endLabel)
+                }
+            }
+            DataType.ARRAY_W, DataType.ARRAY_UW -> {
+                when {
+
+                    // words, step 1 or -1
+
+                    stepsize == 1 || stepsize == -1 -> {
+                        val varname = asmgen.asmVariableName(stmt.loopVar)
+                        assignLoopvar(stmt, range)
+                        asmgen.assignExpressionToRegister(range.to, RegisterOrPair.AY)
+                        asmgen.out("""
+                            sty  $modifiedLabel+1
+                            sta  $modifiedLabel2+1
+$loopLabel""")
+                        asmgen.translate(stmt.body)
+                        asmgen.out("""
+                lda  $varname+1
+$modifiedLabel  cmp  #0    ; modified 
+                bne  +
+                lda  $varname
+$modifiedLabel2 cmp  #0    ; modified 
+                beq  $endLabel""")
+                        if(stepsize==1) {
+                            asmgen.out("""
++               inc  $varname
+                bne  $loopLabel
+                inc  $varname+1""")
+                            asmgen.jmp(loopLabel)
+                        } else {
+                            asmgen.out("""
++               lda  $varname
+                bne  +
+                dec  $varname+1
++               dec  $varname""")
+                            asmgen.jmp(loopLabel)
+                        }
+                        asmgen.out(endLabel)
+                    }
+                    stepsize > 0 -> {
+
+                        // (u)words, step >= 2
+                        val varname = asmgen.asmVariableName(stmt.loopVar)
+                        assignLoopvar(stmt, range)
+                        asmgen.assignExpressionToRegister(range.to, RegisterOrPair.AY)
+                        asmgen.out("""
+                            sty  $modifiedLabel+1
+                            sta  $modifiedLabel2+1
+$loopLabel""")
+                        asmgen.translate(stmt.body)
+
+                        if (iterableDt == DataType.ARRAY_UW) {
+                            asmgen.out("""
+                lda  $varname
+                clc
+                adc  #<$stepsize
+                sta  $varname
+                lda  $varname+1
+                adc  #>$stepsize
+                sta  $varname+1
+$modifiedLabel  cmp  #0     ; modified
+                bcc  $loopLabel
+                bne  $endLabel
+$modifiedLabel2 lda  #0     ; modified
+                cmp  $varname
+                bcc  $endLabel
+                bcs  $loopLabel
+$endLabel""")
+                        } else {
+                            asmgen.out("""
+                lda  $varname
+                clc
+                adc  #<$stepsize
+                sta  $varname
+                lda  $varname+1
+                adc  #>$stepsize
+                sta  $varname+1
+$modifiedLabel2 lda  #0   ; modified
+                cmp  $varname
+$modifiedLabel  lda  #0   ; modified
+                sbc  $varname+1
+                bvc  +
+                eor  #$80
++               bpl  $loopLabel                
+$endLabel""")
+                        }
+                    }
+                    else -> {
+
+                        // (u)words, step <= -2
+                        val varname = asmgen.asmVariableName(stmt.loopVar)
+                        assignLoopvar(stmt, range)
+                        asmgen.assignExpressionToRegister(range.to, RegisterOrPair.AY)
+                        asmgen.out("""
+                            sty  $modifiedLabel+1
+                            sta  $modifiedLabel2+1
+$loopLabel""")
+                        asmgen.translate(stmt.body)
+
+                        if(iterableDt==DataType.ARRAY_UW) {
+                            asmgen.out("""
+                lda  $varname
+                sec
+                sbc  #<${stepsize.absoluteValue}
+                sta  $varname
+                lda  $varname+1
+                sbc  #>${stepsize.absoluteValue}
+                sta  $varname+1
+$modifiedLabel  cmp  #0    ; modified                
+                bcc  $endLabel
+                bne  $loopLabel
+                lda  $varname
+$modifiedLabel2 cmp  #0    ; modified 
+                bcs  $loopLabel
+$endLabel""")
+                        } else {
+                            asmgen.out("""
+                lda  $varname
+                sec
+                sbc  #<${stepsize.absoluteValue}
+                sta  $varname
+                pha
+                lda  $varname+1
+                sbc  #>${stepsize.absoluteValue}
+                sta  $varname+1
+                pla
+$modifiedLabel2 cmp  #0    ; modified 
+                lda  $varname+1
+$modifiedLabel  sbc  #0    ; modified
+                bvc  +
+                eor  #$80
++               bpl  $loopLabel                
+$endLabel""")
+                        }
+                    }
+                }
+            }
+            else -> throw AssemblyError("range expression can only be byte or word")
+        }
+
+        asmgen.loopEndLabels.pop()
+    }
+
+    private fun translateForOverIterableVar(stmt: ForLoop, iterableDt: DataType, ident: IdentifierReference) {
+        val loopLabel = asmgen.makeLabel("for_loop")
+        val endLabel = asmgen.makeLabel("for_end")
+        asmgen.loopEndLabels.push(endLabel)
+        val iterableName = asmgen.asmVariableName(ident)
+        val decl = ident.targetVarDecl(program)!!
+        when(iterableDt) {
+            DataType.STR -> {
+                asmgen.out("""
+                    lda  #<$iterableName
+                    ldy  #>$iterableName
+                    sta  $loopLabel+1
+                    sty  $loopLabel+2
+$loopLabel          lda  ${65535.toHex()}       ; modified
+                    beq  $endLabel
+                    sta  ${asmgen.asmVariableName(stmt.loopVar)}""")
+                asmgen.translate(stmt.body)
+                asmgen.out("""
+                    inc  $loopLabel+1
+                    bne  $loopLabel
+                    inc  $loopLabel+2
+                    bne  $loopLabel
+$endLabel""")
+            }
+            DataType.ARRAY_UB, DataType.ARRAY_B -> {
+                val length = decl.arraysize!!.constIndex()!!
+                val indexVar = asmgen.makeLabel("for_index")
+                asmgen.out("""
+                    ldy  #0
+$loopLabel          sty  $indexVar
+                    lda  $iterableName,y
+                    sta  ${asmgen.asmVariableName(stmt.loopVar)}""")
+                asmgen.translate(stmt.body)
+                if(length<=255) {
+                    asmgen.out("""
+                        ldy  $indexVar
+                        iny
+                        cpy  #$length
+                        beq  $endLabel
+                        bne  $loopLabel""")
+                } else {
+                    // length is 256
+                    asmgen.out("""
+                        ldy  $indexVar
+                        iny
+                        bne  $loopLabel
+                        beq  $endLabel""")
+                }
+                if(length>=16) {
+                    // allocate index var on ZP if possible
+                    val result = asmgen.zeropage.allocate(listOf(indexVar), DataType.UBYTE, null, stmt.position, asmgen.errors)
+                    result.fold(
+                        success = { (address,_)-> asmgen.out("""$indexVar = $address  ; auto zp UBYTE""") },
+                        failure = { asmgen.out("$indexVar    .byte  0") }
+                    )
+                } else {
+                    asmgen.out("$indexVar    .byte  0")
+                }
+                asmgen.out(endLabel)
+            }
+            DataType.ARRAY_W, DataType.ARRAY_UW -> {
+                val length = decl.arraysize!!.constIndex()!! * 2
+                val indexVar = asmgen.makeLabel("for_index")
+                val loopvarName = asmgen.asmVariableName(stmt.loopVar)
+                asmgen.out("""
+                    ldy  #0
+$loopLabel          sty  $indexVar
+                    lda  $iterableName,y
+                    sta  $loopvarName
+                    lda  $iterableName+1,y
+                    sta  $loopvarName+1""")
+                asmgen.translate(stmt.body)
+                if(length<=127) {
+                    asmgen.out("""
+                        ldy  $indexVar
+                        iny
+                        iny
+                        cpy  #$length
+                        beq  $endLabel
+                        bne  $loopLabel""")
+                } else {
+                    // length is 128 words, 256 bytes
+                    asmgen.out("""
+                        ldy  $indexVar
+                        iny
+                        iny
+                        bne  $loopLabel
+                        beq  $endLabel""")
+                }
+                if(length>=16) {
+                    // allocate index var on ZP if possible
+                    val result = asmgen.zeropage.allocate(listOf(indexVar), DataType.UBYTE, null, stmt.position, asmgen.errors)
+                    result.fold(
+                        success = { (address,_)-> asmgen.out("""$indexVar = $address  ; auto zp UBYTE""") },
+                        failure = { asmgen.out("$indexVar    .byte  0") }
+                    )
+                } else {
+                    asmgen.out("$indexVar    .byte  0")
+                }
+                asmgen.out(endLabel)
+            }
+            DataType.ARRAY_F -> {
+                throw AssemblyError("for loop with floating point variables is not supported")
+            }
+            else -> throw AssemblyError("can't iterate over $iterableDt")
+        }
+        asmgen.loopEndLabels.pop()
+    }
+
+    private fun translateForOverConstRange(stmt: ForLoop, iterableDt: DataType, range: IntProgression) {
+        if (range.isEmpty() || range.step==0)
+            throw AssemblyError("empty range or step 0")
+        if(iterableDt==DataType.ARRAY_B || iterableDt==DataType.ARRAY_UB) {
+            if(range.step==1 && range.last>range.first) return translateForSimpleByteRangeAsc(stmt, range)
+            if(range.step==-1 && range.last<range.first) return translateForSimpleByteRangeDesc(stmt, range)
+        }
+        else if(iterableDt==DataType.ARRAY_W || iterableDt==DataType.ARRAY_UW) {
+            if(range.step==1 && range.last>range.first) return translateForSimpleWordRangeAsc(stmt, range)
+            if(range.step==-1 && range.last<range.first) return translateForSimpleWordRangeDesc(stmt, range)
+        }
+
+        // not one of the easy cases, generate more complex code...
+        val loopLabel = asmgen.makeLabel("for_loop")
+        val endLabel = asmgen.makeLabel("for_end")
+        asmgen.loopEndLabels.push(endLabel)
+        when(iterableDt) {
+            DataType.ARRAY_B, DataType.ARRAY_UB -> {
+                // loop over byte range via loopvar, step >= 2 or <= -2
+                val varname = asmgen.asmVariableName(stmt.loopVar)
+                asmgen.out("""
+                            lda  #${range.first}
+                            sta  $varname
+$loopLabel""")
+                asmgen.translate(stmt.body)
+                when (range.step) {
+                    0, 1, -1 -> {
+                        throw AssemblyError("step 0, 1 and -1 should have been handled specifically  $stmt")
+                    }
+                    2 -> {
+                        if(range.last==255 || range.last==254) {
+                            asmgen.out("""
+                                inc  $varname
+                                beq  $endLabel
+                                inc  $varname
+                                bne  $loopLabel""")
+                        } else {
+                            asmgen.out("""
+                                inc  $varname
+                                inc  $varname
+                                lda  $varname
+                                cmp  #${range.last+2}
+                                bne  $loopLabel""")
+                        }
+                    }
+                    -2 -> {
+                        when (range.last) {
+                            0 -> {
+                                asmgen.out("""
+                                    lda  $varname
+                                    beq  $endLabel
+                                    dec  $varname
+                                    dec  $varname""")
+                                asmgen.jmp(loopLabel)
+                            }
+                            1 -> asmgen.out("""
+                                    dec  $varname
+                                    beq  $endLabel
+                                    dec  $varname
+                                    bne  $loopLabel""")
+                            else -> asmgen.out("""
+                                    dec  $varname
+                                    dec  $varname
+                                    lda  $varname
+                                    cmp  #${range.last-2}
+                                    bne  $loopLabel""")
+                        }
+                    }
+                    else -> {
+                        // step <= -3 or >= 3
+                        asmgen.out("""
+                            lda  $varname
+                            cmp  #${range.last}
+                            beq  $endLabel
+                            clc
+                            adc  #${range.step}
+                            sta  $varname""")
+                        asmgen.jmp(loopLabel)
+                    }
+                }
+                asmgen.out(endLabel)
+            }
+            DataType.ARRAY_W, DataType.ARRAY_UW -> {
+                // loop over word range via loopvar, step >= 2 or <= -2
+                val varname = asmgen.asmVariableName(stmt.loopVar)
+                when (range.step) {
+                    0, 1, -1 -> {
+                        throw AssemblyError("step 0, 1 and -1 should have been handled specifically  $stmt")
+                    }
+                    else -> {
+                        // word, step >= 2 or <= -2
+                        // note: range.last has already been adjusted by kotlin itself to actually be the last value of the sequence
+                        asmgen.out("""
+                            lda  #<${range.first}
+                            ldy  #>${range.first}
+                            sta  $varname
+                            sty  $varname+1
+$loopLabel""")
+                        asmgen.translate(stmt.body)
+                        asmgen.out("""
+                            lda  $varname
+                            cmp  #<${range.last}
+                            bne  +
+                            lda  $varname+1
+                            cmp  #>${range.last}
+                            bne  +
+                            beq  $endLabel
++                           lda  $varname
+                            clc
+                            adc  #<${range.step}
+                            sta  $varname
+                            lda  $varname+1
+                            adc  #>${range.step}
+                            sta  $varname+1""")
+                        asmgen.jmp(loopLabel)
+                        asmgen.out(endLabel)
+                    }
+                }
+            }
+            else -> throw AssemblyError("range expression can only be byte or word")
+        }
+        asmgen.loopEndLabels.pop()
+    }
+
+    private fun translateForSimpleByteRangeAsc(stmt: ForLoop, range: IntProgression) {
+        val loopLabel = asmgen.makeLabel("for_loop")
+        val endLabel = asmgen.makeLabel("for_end")
+        asmgen.loopEndLabels.push(endLabel)
+        val varname = asmgen.asmVariableName(stmt.loopVar)
+        asmgen.out("""
+                lda  #${range.first}
+                sta  $varname
+$loopLabel""")
+        asmgen.translate(stmt.body)
+        if (range.last == 255) {
+            asmgen.out("""
+                inc  $varname
+                bne  $loopLabel
+$endLabel""")
+        } else {
+            asmgen.out("""
+                inc  $varname
+                lda  $varname
+                cmp  #${range.last+1}
+                bne  $loopLabel
+$endLabel""")
+        }
+        asmgen.loopEndLabels.pop()
+    }
+
+    private fun translateForSimpleByteRangeDesc(stmt: ForLoop, range: IntProgression) {
+        val loopLabel = asmgen.makeLabel("for_loop")
+        val endLabel = asmgen.makeLabel("for_end")
+        asmgen.loopEndLabels.push(endLabel)
+        val varname = asmgen.asmVariableName(stmt.loopVar)
+        asmgen.out("""
+                    lda  #${range.first}
+                    sta  $varname
+$loopLabel""")
+        asmgen.translate(stmt.body)
+        when (range.last) {
+            0 -> {
+                asmgen.out("""
+                    lda  $varname
+                    beq  $endLabel
+                    dec  $varname""")
+                asmgen.jmp(loopLabel)
+                asmgen.out(endLabel)
+            }
+            1 -> {
+                asmgen.out("""
+                    dec  $varname
+                    bne  $loopLabel
+$endLabel""")
+            }
+            else -> {
+                asmgen.out("""
+                    dec  $varname
+                    lda  $varname
+                    cmp  #${range.last-1}
+                    bne  $loopLabel
+$endLabel""")
+            }
+        }
+        asmgen.loopEndLabels.pop()
+    }
+
+    private fun translateForSimpleWordRangeAsc(stmt: ForLoop, range: IntProgression) {
+        val loopLabel = asmgen.makeLabel("for_loop")
+        val endLabel = asmgen.makeLabel("for_end")
+        asmgen.loopEndLabels.push(endLabel)
+        val varname = asmgen.asmVariableName(stmt.loopVar)
+        asmgen.out("""
+            lda  #<${range.first}
+            ldy  #>${range.first}
+            sta  $varname
+            sty  $varname+1
+$loopLabel""")
+        asmgen.translate(stmt.body)
+        asmgen.out("""
+            lda  $varname
+            cmp  #<${range.last}
+            bne  +
+            lda  $varname+1
+            cmp  #>${range.last}
+            beq  $endLabel
++           inc  $varname
+            bne  $loopLabel
+            inc  $varname+1""")
+        asmgen.jmp(loopLabel)
+        asmgen.out(endLabel)
+        asmgen.loopEndLabels.pop()
+    }
+
+    private fun translateForSimpleWordRangeDesc(stmt: ForLoop, range: IntProgression) {
+        val loopLabel = asmgen.makeLabel("for_loop")
+        val endLabel = asmgen.makeLabel("for_end")
+        asmgen.loopEndLabels.push(endLabel)
+        val varname = asmgen.asmVariableName(stmt.loopVar)
+        asmgen.out("""
+            lda  #<${range.first}
+            ldy  #>${range.first}
+            sta  $varname
+            sty  $varname+1
+$loopLabel""")
+        asmgen.translate(stmt.body)
+        asmgen.out("""
+            lda  $varname
+            cmp  #<${range.last}
+            bne  +
+            lda  $varname+1
+            cmp  #>${range.last}
+            beq  $endLabel
++           lda  $varname
+            bne  +
+            dec  $varname+1
++           dec  $varname""")
+        asmgen.jmp(loopLabel)
+        asmgen.out(endLabel)
+        asmgen.loopEndLabels.pop()
+    }
+
+    private fun assignLoopvar(stmt: ForLoop, range: RangeExpression) =
+        asmgen.assignExpressionToVariable(
+            range.from,
+            asmgen.asmVariableName(stmt.loopVar),
+            stmt.loopVarDt(program).getOrElse { throw AssemblyError("unknown dt") },
+            stmt.definingSubroutine)
+}

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

@@ -0,0 +1,443 @@
+package prog8.codegen.target.cpu6502.codegen
+
+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.NumericLiteralValue
+import prog8.ast.statements.*
+import prog8.codegen.target.AssemblyError
+import prog8.codegen.target.cpu6502.codegen.assignment.AsmAssignSource
+import prog8.codegen.target.cpu6502.codegen.assignment.AsmAssignTarget
+import prog8.codegen.target.cpu6502.codegen.assignment.AsmAssignment
+import prog8.codegen.target.cpu6502.codegen.assignment.TargetStorageKind
+import prog8.compilerinterface.CpuType
+
+
+internal class FunctionCallAsmGen(private val program: Program, private val asmgen: AsmGen) {
+
+    internal fun translateFunctionCallStatement(stmt: IFunctionCall) {
+        saveXbeforeCall(stmt)
+        translateFunctionCall(stmt, false)
+        restoreXafterCall(stmt)
+        // just ignore any result values from the function call.
+    }
+
+    internal fun saveXbeforeCall(stmt: IFunctionCall) {
+        val sub = stmt.target.targetSubroutine(program) ?: throw AssemblyError("undefined subroutine ${stmt.target}")
+        if(sub.shouldSaveX()) {
+            val regSaveOnStack = sub.asmAddress==null       // rom-routines don't require registers to be saved on stack, normal subroutines do because they can contain nested calls
+            if(regSaveOnStack)
+                asmgen.saveRegisterStack(CpuRegister.X, sub.shouldKeepA().saveOnEntry)
+            else
+                asmgen.saveRegisterLocal(CpuRegister.X, (stmt as Node).definingSubroutine!!)
+        }
+    }
+
+    internal fun saveXbeforeCall(gosub: GoSub) {
+        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)
+                asmgen.saveRegisterStack(CpuRegister.X, sub.shouldKeepA().saveOnEntry)
+            else
+                asmgen.saveRegisterLocal(CpuRegister.X, gosub.definingSubroutine!!)
+        }
+    }
+
+    internal fun restoreXafterCall(stmt: IFunctionCall) {
+        val sub = stmt.target.targetSubroutine(program) ?: throw AssemblyError("undefined subroutine ${stmt.target}")
+        if(sub.shouldSaveX()) {
+            val regSaveOnStack = sub.asmAddress==null       // rom-routines don't require registers to be saved on stack, normal subroutines do because they can contain nested calls
+            if(regSaveOnStack)
+                asmgen.restoreRegisterStack(CpuRegister.X, sub.shouldKeepA().saveOnReturn)
+            else
+                asmgen.restoreRegisterLocal(CpuRegister.X)
+        }
+    }
+
+    internal fun restoreXafterCall(gosub: GoSub) {
+        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)
+                asmgen.restoreRegisterStack(CpuRegister.X, sub.shouldKeepA().saveOnReturn)
+            else
+                asmgen.restoreRegisterLocal(CpuRegister.X)
+        }
+    }
+
+    internal fun optimizeIntArgsViaRegisters(sub: Subroutine) =
+        (sub.parameters.size==1 && sub.parameters[0].type in IntegerDatatypes)
+                || (sub.parameters.size==2 && sub.parameters[0].type in ByteDatatypes && sub.parameters[1].type in ByteDatatypes)
+
+    internal fun translateFunctionCall(call: IFunctionCall, isExpression: Boolean) {
+        // Output only the code to set up the parameters and perform the actual call
+        // NOTE: does NOT output the code to deal with the result values!
+        // NOTE: does NOT output code to save/restore the X register for this call! Every caller should deal with this in their own way!!
+        //       (you can use subroutine.shouldSaveX() and saveX()/restoreX() routines as a help for this)
+
+        val sub = call.target.targetSubroutine(program) ?: throw AssemblyError("undefined subroutine ${call.target}")
+        val subAsmName = asmgen.asmSymbolName(call.target)
+
+        if(!isExpression && !sub.isAsmSubroutine) {
+            if(!optimizeIntArgsViaRegisters(sub))
+                throw AssemblyError("functioncall statements to non-asmsub should have been replaced by GoSub $call")
+        }
+
+        if(sub.isAsmSubroutine) {
+            argumentsViaRegisters(sub, call)
+            if (sub.inline && asmgen.options.optimize) {
+                // inline the subroutine.
+                // we do this by copying the subroutine's statements at the call site.
+                // NOTE: *if* there is a return statement, it will be the only one, and the very last statement of the subroutine
+                // (this condition has been enforced by an ast check earlier)
+                asmgen.out("  \t; inlined routine follows: ${sub.name}")
+                val assembly = sub.statements.single() as InlineAssembly
+                asmgen.translate(assembly)
+                asmgen.out("  \t; inlined routine end: ${sub.name}")
+            } else {
+                asmgen.out("  jsr  $subAsmName")
+            }
+        }
+        else {
+            if(sub.inline)
+                throw AssemblyError("can only reliably inline asmsub routines at this time")
+
+            if(optimizeIntArgsViaRegisters(sub)) {
+                if(sub.parameters.size==1) {
+                    val register = if (sub.parameters[0].type in ByteDatatypes) RegisterOrPair.A else RegisterOrPair.AY
+                    argumentViaRegister(sub, IndexedValue(0, sub.parameters[0]), call.args[0], register)
+                } else {
+                    // 2 byte params, second in Y, first in A
+                    argumentViaRegister(sub, IndexedValue(0, sub.parameters[0]), call.args[0], RegisterOrPair.A)
+                    if(!call.args[1].isSimple)
+                        asmgen.out("  pha")
+                    argumentViaRegister(sub, IndexedValue(1, sub.parameters[1]), call.args[1], RegisterOrPair.Y)
+                    if(!call.args[1].isSimple)
+                        asmgen.out("  pla")
+                }
+            } else {
+                argumentsViaVariables(sub, call)
+            }
+            asmgen.out("  jsr  $subAsmName")
+        }
+
+        // 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)
+            } else {
+                asmgen.asmsubArgsEvalOrder(sub).forEach {
+                    val param = sub.parameters[it]
+                    val arg = call.args[it]
+                    argumentViaRegister(sub, IndexedValue(it, param), arg)
+                }
+            }
+        }
+    }
+
+    private fun registerArgsViaStackEvaluation(stmt: IFunctionCall, sub: Subroutine) {
+        // this is called when one or more of the arguments are 'complex' and
+        // cannot be assigned to a register easily or risk clobbering other registers.
+        // TODO find another way to prepare the arguments, without using the eval stack
+
+        if(sub.parameters.isEmpty())
+            return
+
+
+        // 1. load all arguments reversed onto the stack: first arg goes last (is on top).
+
+        for (arg in stmt.args.reversed())
+            asmgen.translateExpression(arg)
+
+        // TODO here's an alternative to the above, but for now generates bigger code due to intermediate register steps:
+//        for (arg in stmt.args.reversed()) {
+//            // note this stuff below is needed to (eventually) avoid calling asmgen.translateExpression()
+//            // TODO also This STILL requires the translateNormalAssignment() to be fixed to avoid stack eval for expressions...
+//            val dt = arg.inferType(program).getOr(DataType.UNDEFINED)
+//            asmgen.assignExpressionTo(arg, AsmAssignTarget(TargetStorageKind.STACK, program, asmgen, dt, sub))
+//        }
+
+        var argForCarry: IndexedValue<Pair<Expression, RegisterOrStatusflag>>? = null
+        var argForXregister: IndexedValue<Pair<Expression, RegisterOrStatusflag>>? = null
+        var argForAregister: IndexedValue<Pair<Expression, RegisterOrStatusflag>>? = null
+
+        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.${
+                                    argi.value.second.registerOrPair.toString().lowercase()
+                                }+1
+                            """)
+                        else -> throw AssemblyError("weird dt")
+                    }
+                }
+                else -> throw AssemblyError("weird argument")
+            }
+        }
+
+        if(argForCarry!=null) {
+            val plusIdxStr = if(argForCarry.index==0) "" else "+${argForCarry.index}"
+            asmgen.out("""
+                clc
+                lda  P8ESTACK_LO$plusIdxStr,x
+                beq  +
+                sec
++               php""")             // push the status flags
+        }
+
+        if(argForAregister!=null) {
+            val plusIdxStr = if(argForAregister.index==0) "" else "+${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) {
+        // pass parameter via a regular variable (not via registers)
+        val valueIDt = value.inferType(program)
+        val valueDt = valueIDt.getOrElse { throw AssemblyError("unknown dt") }
+        if(!isArgumentTypeCompatible(valueDt, parameter.type))
+            throw AssemblyError("argument type incompatible")
+
+        val varName = asmgen.asmVariableName(sub.scopedName + parameter.name)
+        asmgen.assignExpressionToVariable(value, varName, parameter.type, sub)
+    }
+
+    private fun argumentViaRegister(sub: Subroutine, parameter: IndexedValue<SubroutineParameter>, value: Expression, registerOverride: RegisterOrPair? = null) {
+        // pass argument via a register parameter
+        val valueIDt = value.inferType(program)
+        val valueDt = valueIDt.getOrElse { throw AssemblyError("unknown dt") }
+        if(!isArgumentTypeCompatible(valueDt, parameter.value.type))
+            throw AssemblyError("argument type incompatible")
+
+        val paramRegister = if(registerOverride==null) sub.asmParameterRegisters[parameter.index] else RegisterOrStatusflag(registerOverride, null)
+        val statusflag = paramRegister.statusflag
+        val register = paramRegister.registerOrPair
+        val requiredDt = parameter.value.type
+        if(requiredDt!=valueDt) {
+            if(valueDt largerThan requiredDt)
+                throw AssemblyError("can only convert byte values to word param types")
+        }
+        if (statusflag!=null) {
+            if(requiredDt!=valueDt)
+                throw AssemblyError("for statusflag, byte value is required")
+            if (statusflag == Statusflag.Pc) {
+                // this param needs to be set last, right before the jsr
+                // for now, this is already enforced on the subroutine definition by the Ast Checker
+                when(value) {
+                    is NumericLiteralValue -> {
+                        val carrySet = value.number.toInt() != 0
+                        asmgen.out(if(carrySet) "  sec" else "  clc")
+                    }
+                    is IdentifierReference -> {
+                        val sourceName = asmgen.asmVariableName(value)
+                        asmgen.out("""
+                            pha
+                            clc
+                            lda  $sourceName
+                            beq  +
+                            sec  
++                           pla""")
+                    }
+                    else -> {
+                        asmgen.assignExpressionToRegister(value, RegisterOrPair.A)
+                        asmgen.out("""
+                            beq  +
+                            sec
+                            bcs  ++
++                           clc
++""")
+                    }
+                }
+            } else throw AssemblyError("can only use Carry as status flag parameter")
+        }
+        else {
+            // via register or register pair
+            register!!
+            if(requiredDt largerThan valueDt) {
+                // we need to sign extend the source, do this via temporary word variable
+                asmgen.assignExpressionToVariable(value, "P8ZP_SCRATCH_W1", DataType.UBYTE, sub)
+                asmgen.signExtendVariableLsb("P8ZP_SCRATCH_W1", valueDt)
+                asmgen.assignVariableToRegister("P8ZP_SCRATCH_W1", register)
+            } else {
+                val target: AsmAssignTarget =
+                    if(parameter.value.type in ByteDatatypes && (register==RegisterOrPair.AX || register == RegisterOrPair.AY || register==RegisterOrPair.XY || register in Cx16VirtualRegisters))
+                        AsmAssignTarget(TargetStorageKind.REGISTER, program, asmgen, parameter.value.type, sub, register = register)
+                    else {
+                        val signed = parameter.value.type == DataType.BYTE || parameter.value.type == DataType.WORD
+                        AsmAssignTarget.fromRegisters(register, signed, sub, program, asmgen)
+                    }
+                val src = if(valueDt in PassByReferenceDatatypes) {
+                    if(value is IdentifierReference) {
+                        val addr = AddressOf(value, Position.DUMMY)
+                        AsmAssignSource.fromAstSource(addr, program, asmgen).adjustSignedUnsigned(target)
+                    } else {
+                        AsmAssignSource.fromAstSource(value, program, asmgen).adjustSignedUnsigned(target)
+                    }
+                } else {
+                    AsmAssignSource.fromAstSource(value, program, asmgen).adjustSignedUnsigned(target)
+                }
+                asmgen.translateNormalAssignment(AsmAssignment(src, target, false, program.memsizer, Position.DUMMY))
+            }
+        }
+    }
+
+    private fun isArgumentTypeCompatible(argType: DataType, paramType: DataType): Boolean {
+        if(argType isAssignableTo paramType)
+            return true
+        if(argType in ByteDatatypes && paramType in ByteDatatypes)
+            return true
+        if(argType in WordDatatypes && paramType in WordDatatypes)
+            return true
+
+        // we have a special rule for some types.
+        // strings are assignable to UWORD, for example, and vice versa
+        if(argType==DataType.STR && paramType==DataType.UWORD)
+            return true
+        if(argType==DataType.UWORD && paramType == DataType.STR)
+            return true
+
+        return false
+    }
+}

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

@@ -0,0 +1,128 @@
+package prog8.codegen.target.cpu6502.codegen
+
+import prog8.ast.Program
+import prog8.ast.base.*
+import prog8.ast.expressions.IdentifierReference
+import prog8.ast.expressions.NumericLiteralValue
+import prog8.ast.statements.PostIncrDecr
+import prog8.ast.toHex
+import prog8.codegen.target.AssemblyError
+
+
+internal class PostIncrDecrAsmGen(private val program: Program, private val asmgen: AsmGen) {
+    internal fun translate(stmt: PostIncrDecr) {
+        val incr = stmt.operator=="++"
+        val targetIdent = stmt.target.identifier
+        val targetMemory = stmt.target.memoryAddress
+        val targetArrayIdx = stmt.target.arrayindexed
+        val scope = stmt.definingSubroutine
+        when {
+            targetIdent!=null -> {
+                val what = asmgen.asmVariableName(targetIdent)
+                when (stmt.target.inferType(program).getOr(DataType.UNDEFINED)) {
+                    in ByteDatatypes -> asmgen.out(if (incr) "  inc  $what" else "  dec  $what")
+                    in WordDatatypes -> {
+                        if(incr)
+                            asmgen.out(" inc  $what |  bne  + |  inc  $what+1 |+")
+                        else
+                            asmgen.out("""
+        lda  $what
+        bne  +
+        dec  $what+1
++       dec  $what 
+""")
+                    }
+                    DataType.FLOAT -> {
+                        asmgen.out("  lda  #<$what |  ldy  #>$what")
+                        asmgen.out(if(incr) "  jsr  floats.inc_var_f" else "  jsr  floats.dec_var_f")
+                    }
+                    else -> throw AssemblyError("need numeric type")
+                }
+            }
+            targetMemory!=null -> {
+                when (val addressExpr = targetMemory.addressExpression) {
+                    is NumericLiteralValue -> {
+                        val what = addressExpr.number.toHex()
+                        asmgen.out(if(incr) "  inc  $what" else "  dec  $what")
+                    }
+                    is IdentifierReference -> {
+                        val what = asmgen.asmVariableName(addressExpr)
+                        asmgen.out("  lda  $what |  sta  (+) +1 |  lda  $what+1 |  sta  (+) +2")
+                        if(incr)
+                            asmgen.out("+\tinc  ${'$'}ffff\t; modified")
+                        else
+                            asmgen.out("+\tdec  ${'$'}ffff\t; modified")
+                    }
+                    else -> {
+                        asmgen.assignExpressionToRegister(addressExpr, RegisterOrPair.AY)
+                        asmgen.out("  sta  (+) + 1 |  sty  (+) + 2")
+                        if(incr)
+                            asmgen.out("+\tinc  ${'$'}ffff\t; modified")
+                        else
+                            asmgen.out("+\tdec  ${'$'}ffff\t; modified")
+                    }
+                }
+            }
+            targetArrayIdx!=null -> {
+                val asmArrayvarname = asmgen.asmVariableName(targetArrayIdx.arrayvar)
+                val elementDt = targetArrayIdx.inferType(program).getOr(DataType.UNDEFINED)
+                val constIndex = targetArrayIdx.indexer.constIndex()
+                if(constIndex!=null) {
+                    val indexValue = constIndex * program.memsizer.memorySize(elementDt)
+                    when(elementDt) {
+                        in ByteDatatypes -> asmgen.out(if (incr) "  inc  $asmArrayvarname+$indexValue" else "  dec  $asmArrayvarname+$indexValue")
+                        in WordDatatypes -> {
+                            if(incr)
+                                asmgen.out(" inc  $asmArrayvarname+$indexValue |  bne  + |  inc  $asmArrayvarname+$indexValue+1 |+")
+                            else
+                                asmgen.out("""
+    lda  $asmArrayvarname+$indexValue
+    bne  +
+    dec  $asmArrayvarname+$indexValue+1
++       dec  $asmArrayvarname+$indexValue 
+""")
+                        }
+                        DataType.FLOAT -> {
+                            asmgen.out("  lda  #<($asmArrayvarname+$indexValue) |  ldy  #>($asmArrayvarname+$indexValue)")
+                            asmgen.out(if(incr) "  jsr  floats.inc_var_f" else "  jsr  floats.dec_var_f")
+                        }
+                        else -> throw AssemblyError("need numeric type")
+                    }
+                }
+                else
+                {
+                    asmgen.loadScaledArrayIndexIntoRegister(targetArrayIdx, elementDt, CpuRegister.A)
+                    asmgen.saveRegisterLocal(CpuRegister.X, scope!!)
+                    asmgen.out("  tax")
+                    when(elementDt) {
+                        in ByteDatatypes -> {
+                            asmgen.out(if(incr) "  inc  $asmArrayvarname,x" else "  dec  $asmArrayvarname,x")
+                        }
+                        in WordDatatypes -> {
+                            if(incr)
+                                asmgen.out(" inc  $asmArrayvarname,x |  bne  + |  inc  $asmArrayvarname+1,x |+")
+                            else
+                                asmgen.out("""
+    lda  $asmArrayvarname,x
+    bne  +
+    dec  $asmArrayvarname+1,x
++       dec  $asmArrayvarname,x 
+""")
+                        }
+                        DataType.FLOAT -> {
+                            asmgen.out("""
+                    ldy  #>$asmArrayvarname
+                    clc
+                    adc  #<$asmArrayvarname
+                    bcc  +
+                    iny
++                       jsr  floats.inc_var_f""")
+                        }
+                        else -> throw AssemblyError("weird array elt dt")
+                    }
+                    asmgen.restoreRegisterLocal(CpuRegister.X)
+                }
+            }
+        }
+    }
+}

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

@@ -0,0 +1,227 @@
+package prog8.codegen.target.cpu6502.codegen.assignment
+
+import prog8.ast.Program
+import prog8.ast.base.*
+import prog8.ast.expressions.*
+import prog8.ast.statements.*
+import prog8.compilerinterface.IMemSizer
+import prog8.codegen.target.AssemblyError
+import prog8.codegen.target.cpu6502.codegen.AsmGen
+
+
+internal enum class TargetStorageKind {
+    VARIABLE,
+    ARRAY,
+    MEMORY,
+    REGISTER,
+    STACK
+}
+
+internal enum class SourceStorageKind {
+    LITERALNUMBER,
+    VARIABLE,
+    ARRAY,
+    MEMORY,
+    REGISTER,
+    STACK,              // value is already present on stack
+    EXPRESSION,         // expression in ast-form, still to be evaluated
+}
+
+internal class AsmAssignTarget(val kind: TargetStorageKind,
+                               private val program: Program,
+                               private val asmgen: AsmGen,
+                               val datatype: DataType,
+                               val scope: Subroutine?,
+                               private val variableAsmName: String? = null,
+                               val array: ArrayIndexedExpression? = null,
+                               val memory: DirectMemoryWrite? = null,
+                               val register: RegisterOrPair? = null,
+                               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)
+            variableAsmName!!
+        else
+            asmgen.asmVariableName(array.arrayvar)
+    }
+
+    lateinit var origAssign: AsmAssignment
+
+    init {
+        if(register!=null && datatype !in NumericDatatypes)
+            throw AssemblyError("register must be integer or float type")
+    }
+
+    companion object {
+        fun fromAstAssignment(assign: Assignment, program: Program, asmgen: AsmGen): AsmAssignTarget {
+            with(assign.target) {
+                val idt = inferType(program)
+                val dt = idt.getOrElse { throw AssemblyError("unknown dt") }
+                when {
+                    identifier != null -> {
+                        val parameter = identifier!!.targetVarDecl(program)?.subroutineParameter
+                        if (parameter!=null) {
+                            val sub = parameter.definingSubroutine!!
+                            if (sub.isAsmSubroutine) {
+                                val reg = sub.asmParameterRegisters[sub.parameters.indexOf(parameter)]
+                                if(reg.statusflag!=null)
+                                    throw AssemblyError("can't assign value to processor statusflag directly")
+                                else
+                                    return AsmAssignTarget(TargetStorageKind.REGISTER, program, asmgen, dt, assign.definingSubroutine, register=reg.registerOrPair, origAstTarget = this)
+                            }
+                        }
+                        return AsmAssignTarget(TargetStorageKind.VARIABLE, program, asmgen, dt, assign.definingSubroutine, variableAsmName = asmgen.asmVariableName(identifier!!), origAstTarget =  this)
+                    }
+                    arrayindexed != null -> return AsmAssignTarget(TargetStorageKind.ARRAY, program, asmgen, dt, assign.definingSubroutine, array = arrayindexed, origAstTarget =  this)
+                    memoryAddress != null -> return AsmAssignTarget(TargetStorageKind.MEMORY, program, asmgen, dt, assign.definingSubroutine, memory =  memoryAddress, origAstTarget =  this)
+                    else -> throw AssemblyError("weird target")
+                }
+            }
+        }
+
+        fun fromRegisters(registers: RegisterOrPair, signed: Boolean, scope: Subroutine?, program: Program, asmgen: AsmGen): AsmAssignTarget =
+                when(registers) {
+                    RegisterOrPair.A,
+                    RegisterOrPair.X,
+                    RegisterOrPair.Y -> AsmAssignTarget(TargetStorageKind.REGISTER, program, asmgen, if(signed) DataType.BYTE else DataType.UBYTE, scope, register = registers)
+                    RegisterOrPair.AX,
+                    RegisterOrPair.AY,
+                    RegisterOrPair.XY -> AsmAssignTarget(TargetStorageKind.REGISTER, program, asmgen, if(signed) DataType.WORD else DataType.UWORD, scope, register = registers)
+                    RegisterOrPair.FAC1,
+                    RegisterOrPair.FAC2 -> AsmAssignTarget(TargetStorageKind.REGISTER, program, asmgen, DataType.FLOAT, scope, register = registers)
+                    RegisterOrPair.R0,
+                    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 -> AsmAssignTarget(TargetStorageKind.REGISTER, program, asmgen, if(signed) DataType.WORD else DataType.UWORD, scope, register = registers)
+                }
+    }
+}
+
+internal class AsmAssignSource(val kind: SourceStorageKind,
+                               private val program: Program,
+                               private val asmgen: AsmGen,
+                               val datatype: DataType,
+                               private val variableAsmName: String? = null,
+                               val array: ArrayIndexedExpression? = null,
+                               val memory: DirectMemoryRead? = null,
+                               val register: RegisterOrPair? = null,
+                               val number: NumericLiteralValue? = null,
+                               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!!
+        else
+            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)
+                return AsmAssignSource(SourceStorageKind.LITERALNUMBER, program, asmgen, cv.type, number = cv)
+
+            return when(value) {
+                is NumericLiteralValue -> throw AssemblyError("should have been constant value")
+                is StringLiteralValue -> throw AssemblyError("string literal value should not occur anymore for asm generation")
+                is ArrayLiteralValue -> throw AssemblyError("array literal value should not occur anymore for asm generation")
+                is IdentifierReference -> {
+                    val parameter = value.targetVarDecl(program)?.subroutineParameter
+                    if(parameter!=null && parameter.definingSubroutine!!.isAsmSubroutine)
+                        throw AssemblyError("can't assign from a asmsub register parameter $value ${value.position}")
+                    val dt = value.inferType(program).getOr(DataType.UNDEFINED)
+                    val varName=asmgen.asmVariableName(value)
+                    // special case: "cx16.r[0-15]" are 16-bits virtual registers of the commander X16 system
+                    if(dt == DataType.UWORD && varName.lowercase().startsWith("cx16.r")) {
+                        val regStr = varName.lowercase().substring(5)
+                        val reg = RegisterOrPair.valueOf(regStr.uppercase())
+                        AsmAssignSource(SourceStorageKind.REGISTER, program, asmgen, dt, register = reg)
+                    } else {
+                        AsmAssignSource(SourceStorageKind.VARIABLE, program, asmgen, dt, variableAsmName = varName)
+                    }
+                }
+                is DirectMemoryRead -> {
+                    AsmAssignSource(SourceStorageKind.MEMORY, program, asmgen, DataType.UBYTE, memory = value)
+                }
+                is ArrayIndexedExpression -> {
+                    val dt = value.inferType(program).getOrElse { throw AssemblyError("unknown dt") }
+                    AsmAssignSource(SourceStorageKind.ARRAY, program, asmgen, dt, array = 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")
+
+                            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")
+                        }
+                    }
+                }
+                else -> {
+                    val dt = value.inferType(program)
+                    AsmAssignSource(SourceStorageKind.EXPRESSION, program, asmgen, dt.getOrElse { throw AssemblyError("unknown dt") }, expression = value)
+                }
+            }
+        }
+    }
+
+    fun adjustSignedUnsigned(target: AsmAssignTarget): AsmAssignSource {
+        // allow some signed/unsigned relaxations
+
+        fun withAdjustedDt(newType: DataType) =
+                AsmAssignSource(kind, program, asmgen, newType, variableAsmName, array, memory, register, number, expression)
+
+        if(target.datatype!=datatype) {
+            if(target.datatype in ByteDatatypes && datatype in ByteDatatypes) {
+                return withAdjustedDt(target.datatype)
+            } else if(target.datatype in WordDatatypes && datatype in WordDatatypes) {
+                return withAdjustedDt(target.datatype)
+            }
+        }
+        return this
+    }
+
+}
+
+
+internal class AsmAssignment(val source: AsmAssignSource,
+                             val target: AsmAssignTarget,
+                             val isAugmentable: Boolean,
+                             memsizer: IMemSizer,
+                             val position: Position) {
+
+    init {
+        if(target.register !in arrayOf(RegisterOrPair.XY, RegisterOrPair.AX, RegisterOrPair.AY))
+            require(source.datatype != DataType.UNDEFINED) { "must not be placeholder/undefined datatype" }
+            require(memsizer.memorySize(source.datatype) <= memsizer.memorySize(target.datatype)) {
+                "source dt size must be less or equal to target dt size at $position"
+            }
+    }
+}

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

@@ -0,0 +1,89 @@
+package prog8.codegen.target.cx16
+
+import prog8.ast.base.DataType
+import prog8.codegen.target.cbm.Mflpt5
+import prog8.codegen.target.cbm.viceMonListName
+import prog8.compilerinterface.*
+import java.io.IOException
+import java.nio.file.Path
+
+
+class CX16MachineDefinition: IMachineDefinition {
+
+    override val cpu = CpuType.CPU65c02
+
+    override val FLOAT_MAX_POSITIVE = Mflpt5.FLOAT_MAX_POSITIVE
+    override val FLOAT_MAX_NEGATIVE = Mflpt5.FLOAT_MAX_NEGATIVE
+    override val FLOAT_MEM_SIZE = Mflpt5.FLOAT_MEM_SIZE
+    override val BASIC_LOAD_ADDRESS = 0x0801u
+    override val RAW_LOAD_ADDRESS = 0x8000u
+
+    // the 2*256 byte evaluation stack (on which bytes, words, and even floats are stored during calculations)
+    override val ESTACK_LO = 0x0400u        //  $0400-$04ff inclusive
+    override val ESTACK_HI = 0x0500u        //  $0500-$05ff inclusive
+
+    override lateinit var zeropage: Zeropage
+
+    override fun getFloat(num: Number) = Mflpt5.fromNumber(num)
+    override fun importLibs(compilerOptions: CompilationOptions, compilationTargetName: String): List<String> {
+        return if (compilerOptions.launcher == LauncherType.BASIC || compilerOptions.output == OutputType.PRG)
+            listOf("syslib")
+        else
+            emptyList()
+    }
+
+    override fun launchEmulator(selectedEmulator: Int, programNameWithPath: Path) {
+        val emulatorName: String
+        val extraArgs: List<String>
+
+        when(selectedEmulator) {
+            1 -> {
+                emulatorName = "x16emu"
+                extraArgs = emptyList()
+            }
+            2 -> {
+                emulatorName = "box16"
+                extraArgs = listOf("-sym", viceMonListName(programNameWithPath.toString()))
+            }
+            else -> {
+                System.err.println("Cx16 target only supports x16emu and box16 emulators.")
+                return
+            }
+        }
+
+        for(emulator in listOf(emulatorName)) {
+            println("\nStarting Commander X16 emulator $emulator...")
+            val cmdline = listOf(emulator, "-scale", "2", "-run", "-prg", "${programNameWithPath}.prg") + extraArgs
+            val processb = ProcessBuilder(cmdline).inheritIO()
+            val process: Process
+            try {
+                process=processb.start()
+            } catch(x: IOException) {
+                continue  // try the next emulator executable
+            }
+            process.waitFor()
+            break
+        }
+    }
+
+    override fun isIOAddress(address: UInt): Boolean = address==0u || address==1u || address in 0x9f00u..0x9fffu
+
+    override fun initializeZeropage(compilerOptions: CompilationOptions) {
+        zeropage = CX16Zeropage(compilerOptions)
+    }
+
+    // 6502 opcodes (including aliases and illegal opcodes), these cannot be used as variable or label names
+    override val opcodeNames = setOf("adc", "and", "asl", "bcc", "bcs",
+            "beq", "bge", "bit", "blt", "bmi", "bne", "bpl", "brk", "bvc", "bvs", "clc",
+            "cld", "cli", "clv", "cmp", "cpx", "cpy", "dec", "dex", "dey",
+            "eor", "gcc", "gcs", "geq", "gge", "glt", "gmi", "gne", "gpl", "gvc", "gvs",
+            "inc", "inx", "iny", "jmp", "jsr",
+            "lda", "ldx", "ldy", "lsr", "nop", "ora", "pha", "php",
+            "pla", "plp", "rol", "ror", "rti", "rts", "sbc",
+            "sec", "sed", "sei",
+            "sta", "stx", "sty", "tax", "tay", "tsx", "txa", "txs", "tya",
+            "bra", "phx", "phy", "plx", "ply", "stz", "trb", "tsb", "bbr", "bbs",
+            "rmb", "smb", "stp", "wai")
+
+
+}

codeGeneration/src/prog8/codegen/target/cx16/CX16Zeropage.kt

@@ -0,0 +1,52 @@
+package prog8.codegen.target.cx16
+
+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) {
+
+    override val SCRATCH_B1 = 0x7au      // temp storage for a single byte
+    override val SCRATCH_REG = 0x7bu     // temp storage for a register, must be B1+1
+    override val SCRATCH_W1 = 0x7cu      // temp storage 1 for a word  $7c+$7d
+    override val SCRATCH_W2 = 0x7eu      // temp storage 2 for a word  $7e+$7f
+
+
+    init {
+        if (options.floats && options.zeropage !in arrayOf(ZeropageType.BASICSAFE, ZeropageType.DONTUSE))
+            throw InternalCompilerException("when floats are enabled, zero page type should be 'basicsafe' or 'dontuse'")
+
+        // the addresses 0x02 to 0x21 (inclusive) are taken for sixteen virtual 16-bit api registers.
+
+        when (options.zeropage) {
+            ZeropageType.FULL -> {
+                free.addAll(0x22u..0xffu)
+            }
+            ZeropageType.KERNALSAFE -> {
+                free.addAll(0x22u..0x7fu)
+                free.addAll(0xa9u..0xffu)
+            }
+            ZeropageType.BASICSAFE -> {
+                free.addAll(0x22u..0x7fu)
+            }
+            ZeropageType.DONTUSE -> {
+                free.clear() // don't use zeropage at all
+            }
+            else -> throw InternalCompilerException("for this machine target, zero page type 'floatsafe' is not available. ${options.zeropage}")
+        }
+
+        removeReservedFromFreePool()
+
+        for(reg in 0..15) {
+            allocatedVariables[listOf("cx16", "r${reg}")] = (2+reg*2).toUInt() to (DataType.UWORD to 2)        // cx16.r0 .. cx16.r15
+            allocatedVariables[listOf("cx16", "r${reg}s")] = (2+reg*2).toUInt() to (DataType.WORD to 2)        // cx16.r0s .. cx16.r15s
+            allocatedVariables[listOf("cx16", "r${reg}L")] = (2+reg*2).toUInt() to (DataType.UBYTE to 1)       // cx16.r0L .. cx16.r15L
+            allocatedVariables[listOf("cx16", "r${reg}H")] = (3+reg*2).toUInt() to (DataType.UBYTE to 1)       // cx16.r0H .. cx16.r15H
+            allocatedVariables[listOf("cx16", "r${reg}sL")] = (2+reg*2).toUInt() to (DataType.BYTE to 1)       // cx16.r0sL .. cx16.r15sL
+            allocatedVariables[listOf("cx16", "r${reg}sH")] = (3+reg*2).toUInt() to (DataType.BYTE to 1)       // cx16.r0sH .. cx16.r15sH
+        }
+
+    }
+}

codeOptimizers/build.gradle

@@ -0,0 +1,44 @@
+
+plugins {
+    id 'java'
+    id 'application'
+    id "org.jetbrains.kotlin.jvm"
+}
+
+java {
+    toolchain {
+        languageVersion = JavaLanguageVersion.of(javaVersion)
+    }
+}
+
+compileKotlin {
+    kotlinOptions {
+        jvmTarget = javaVersion
+    }
+}
+
+compileTestKotlin {
+    kotlinOptions {
+        jvmTarget = javaVersion
+    }
+}
+
+dependencies {
+    implementation project(':compilerInterfaces')
+    implementation project(':compilerAst')
+    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8"
+    // implementation "org.jetbrains.kotlin:kotlin-reflect"
+}
+
+sourceSets {
+    main {
+        java {
+            srcDirs = ["${project.projectDir}/src"]
+        }
+        resources {
+            srcDirs = ["${project.projectDir}/res"]
+        }
+    }
+}
+
+// note: there are no unit tests in this module!

codeOptimizers/codeOptimizers.iml

@@ -2,9 +2,14 @@
 <module type="JAVA_MODULE" version="4">
   <component name="NewModuleRootManager" inherit-compiler-output="true">
     <exclude-output />
-    <content url="file://$MODULE_DIR$" />
+    <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="compilerInterfaces" />
+    <orderEntry type="module" module-name="compilerAst" />
   </component>
 </module>

codeOptimizers/readme-tests.txt

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

codeOptimizers/src/prog8/optimizer/BinExprSplitter.kt

@@ -0,0 +1,129 @@
+package prog8.optimizer
+
+import prog8.ast.IStatementContainer
+import prog8.ast.Node
+import prog8.ast.Program
+import prog8.ast.base.DataType
+import prog8.ast.base.FatalAstException
+import prog8.ast.expressions.BinaryExpression
+import prog8.ast.expressions.IdentifierReference
+import prog8.ast.expressions.TypecastExpression
+import prog8.ast.expressions.AugmentAssignmentOperators
+import prog8.ast.statements.AssignTarget
+import prog8.ast.statements.Assignment
+import prog8.ast.statements.AssignmentOrigin
+import prog8.ast.walk.AstWalker
+import prog8.ast.walk.IAstModification
+import prog8.compilerinterface.CompilationOptions
+import prog8.compilerinterface.ICompilationTarget
+import prog8.compilerinterface.isIOAddress
+
+
+class BinExprSplitter(private val program: Program, private val options: CompilationOptions, private val compTarget: ICompilationTarget) : AstWalker() {
+
+    override fun after(assignment: Assignment, parent: Node): Iterable<IAstModification> {
+
+        if(assignment.value.inferType(program) istype DataType.FLOAT && !options.optimizeFloatExpressions)
+            return noModifications
+
+        val binExpr = assignment.value as? BinaryExpression
+        if (binExpr != null) {
+
+/*
+
+Reduce the complexity of a (binary) expression that has to be evaluated on the eval stack,
+by attempting to splitting it up into individual simple steps.
+We only consider a binary expression *one* level deep (so the operands must not be a combined expression)
+
+
+X =      BinExpr                                    X   =   LeftExpr
+        <operator>                                     followed by
+          /   \             IF 'X' not used         X   =   BinExpr
+         /     \             IN expression ==>             <operator>
+        /       \                                           /   \
+    LeftExpr.  RightExpr.                                  /     \
+                                                          X     RightExpr.
+
+
+ */
+            if(binExpr.operator in AugmentAssignmentOperators && isSimpleTarget(assignment.target)) {
+                if(assignment.target isSameAs binExpr.right)
+                    return noModifications
+                if(assignment.target isSameAs binExpr.left) {
+                    if(binExpr.right.isSimple)
+                        return noModifications
+                    val leftBx = binExpr.left as? BinaryExpression
+                    if(leftBx!=null && (!leftBx.left.isSimple || !leftBx.right.isSimple))
+                        return noModifications
+                    val rightBx = binExpr.right as? BinaryExpression
+                    if(rightBx!=null && (!rightBx.left.isSimple || !rightBx.right.isSimple))
+                        return noModifications
+
+                      // TODO below attempts to remove stack-based evaluated expressions, but often the resulting code is BIGGER, and SLOWER.
+//                    val dt = assignment.target.inferType(program)
+//                    if(!dt.isInteger)
+//                        return noModifications
+//                    val tempVar = IdentifierReference(getTempVarName(dt), binExpr.right.position)
+//                    val assignTempVar = Assignment(
+//                        AssignTarget(tempVar, null, null, binExpr.right.position),
+//                        binExpr.right, binExpr.right.position
+//                    )
+//                    return listOf(
+//                        IAstModification.InsertBefore(assignment, assignTempVar, assignment.parent as IStatementContainer),
+//                        IAstModification.ReplaceNode(binExpr.right, tempVar.copy(), binExpr)
+//                    )
+                }
+
+                if(binExpr.right.isSimple) {
+                    val firstAssign = Assignment(assignment.target.copy(), binExpr.left, AssignmentOrigin.OPTIMIZER, binExpr.left.position)
+                    val targetExpr = assignment.target.toExpression()
+                    val augExpr = BinaryExpression(targetExpr, binExpr.operator, binExpr.right, binExpr.right.position)
+                    return listOf(
+                        IAstModification.ReplaceNode(binExpr, augExpr, assignment),
+                        IAstModification.InsertBefore(assignment, firstAssign, assignment.parent as IStatementContainer)
+                    )
+                }
+            }
+
+            // TODO further unraveling of binary expression trees into flat statements.
+            // however this should probably be done in a more generic way to also work on
+            // the expressiontrees that are not used in an assignment statement...
+        }
+
+        val typecast = assignment.value as? TypecastExpression
+        if(typecast!=null) {
+            val origExpr = typecast.expression as? BinaryExpression
+            if(origExpr!=null) {
+                // 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 = when(val tempDt = origExpr.inferType(program).getOr(DataType.UNDEFINED)) {
+                    DataType.UBYTE -> listOf("prog8_lib", "retval_interm_ub")
+                    DataType.BYTE -> listOf("prog8_lib", "retval_interm_b")
+                    DataType.UWORD -> listOf("prog8_lib", "retval_interm_uw")
+                    DataType.WORD -> listOf("prog8_lib", "retval_interm_w")
+                    DataType.FLOAT -> listOf("floats", "tempvar_swap_float")
+                    else -> throw FatalAstException("invalid dt $tempDt")
+                }
+                val assignTempVar = Assignment(
+                    AssignTarget(IdentifierReference(tempVar, 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)
+                )
+            }
+        }
+
+        return noModifications
+    }
+
+    private fun isSimpleTarget(target: AssignTarget) =
+            if (target.identifier!=null || target.memoryAddress!=null)
+                !target.isIOAddress(compTarget.machine)
+            else
+                false
+
+}

codeOptimizers/src/prog8/optimizer/ConstExprEvaluator.kt

@@ -0,0 +1,278 @@
+package prog8.optimizer
+
+import prog8.ast.base.*
+import prog8.ast.expressions.Expression
+import prog8.ast.expressions.NumericLiteralValue
+import kotlin.math.pow
+
+
+class ConstExprEvaluator {
+
+    fun evaluate(left: NumericLiteralValue, operator: String, right: NumericLiteralValue): Expression {
+        try {
+            return when(operator) {
+                "+" -> plus(left, right)
+                "-" -> minus(left, right)
+                "*" -> multiply(left, right)
+                "/" -> divide(left, right)
+                "%" -> remainder(left, right)
+                "**" -> power(left, right)
+                "&" -> bitwiseand(left, right)
+                "|" -> bitwiseor(left, right)
+                "^" -> bitwisexor(left, right)
+                "and" -> logicaland(left, right)
+                "or" -> logicalor(left, right)
+                "xor" -> logicalxor(left, right)
+                "<" -> NumericLiteralValue.fromBoolean(left < right, left.position)
+                ">" -> NumericLiteralValue.fromBoolean(left > right, left.position)
+                "<=" -> NumericLiteralValue.fromBoolean(left <= right, left.position)
+                ">=" -> NumericLiteralValue.fromBoolean(left >= right, left.position)
+                "==" -> NumericLiteralValue.fromBoolean(left == right, left.position)
+                "!=" -> NumericLiteralValue.fromBoolean(left != right, left.position)
+                "<<" -> shiftedleft(left, right)
+                ">>" -> shiftedright(left, right)
+                else -> throw FatalAstException("const evaluation for invalid operator $operator")
+            }
+        } catch (ax: FatalAstException) {
+            throw ExpressionError(ax.message, left.position)
+        }
+    }
+
+    private fun shiftedright(left: NumericLiteralValue, amount: NumericLiteralValue): Expression {
+        if(left.type !in IntegerDatatypes || amount.type !in IntegerDatatypes)
+            throw ExpressionError("cannot compute $left >> $amount", left.position)
+        val result =
+                if(left.type== DataType.UBYTE || left.type== DataType.UWORD)
+                    left.number.toInt().ushr(amount.number.toInt())
+                else
+                    left.number.toInt().shr(amount.number.toInt())
+        return NumericLiteralValue(left.type, result.toDouble(), left.position)
+    }
+
+    private fun shiftedleft(left: NumericLiteralValue, amount: NumericLiteralValue): Expression {
+        if(left.type !in IntegerDatatypes || amount.type !in IntegerDatatypes)
+            throw ExpressionError("cannot compute $left << $amount", left.position)
+        val result = left.number.toInt().shl(amount.number.toInt())
+        return NumericLiteralValue(left.type, result.toDouble(), left.position)
+    }
+
+    private fun logicalxor(left: NumericLiteralValue, right: NumericLiteralValue): NumericLiteralValue {
+        val error = "cannot compute $left locical-bitxor $right"
+        return when (left.type) {
+            in IntegerDatatypes -> when (right.type) {
+                in IntegerDatatypes -> NumericLiteralValue.fromBoolean((left.number.toInt() != 0) xor (right.number.toInt() != 0), left.position)
+                DataType.FLOAT -> NumericLiteralValue.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 -> NumericLiteralValue.fromBoolean((left.number != 0.0) xor (right.number.toInt() != 0), left.position)
+                DataType.FLOAT -> NumericLiteralValue.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: NumericLiteralValue, right: NumericLiteralValue): NumericLiteralValue {
+        val error = "cannot compute $left locical-or $right"
+        return when (left.type) {
+            in IntegerDatatypes -> when (right.type) {
+                in IntegerDatatypes -> NumericLiteralValue.fromBoolean(left.number.toInt() != 0 || right.number.toInt() != 0, left.position)
+                DataType.FLOAT -> NumericLiteralValue.fromBoolean(left.number.toInt() != 0 || right.number != 0.0, left.position)
+                else -> throw ExpressionError(error, left.position)
+            }
+            DataType.FLOAT -> when (right.type) {
+                in IntegerDatatypes -> NumericLiteralValue.fromBoolean(left.number != 0.0 || right.number.toInt() != 0, left.position)
+                DataType.FLOAT -> NumericLiteralValue.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: NumericLiteralValue, right: NumericLiteralValue): NumericLiteralValue {
+        val error = "cannot compute $left locical-and $right"
+        return when (left.type) {
+            in IntegerDatatypes -> when (right.type) {
+                in IntegerDatatypes -> NumericLiteralValue.fromBoolean(left.number.toInt() != 0 && right.number.toInt() != 0, left.position)
+                DataType.FLOAT -> NumericLiteralValue.fromBoolean(left.number.toInt() != 0 && right.number != 0.0, left.position)
+                else -> throw ExpressionError(error, left.position)
+            }
+            DataType.FLOAT -> when (right.type) {
+                in IntegerDatatypes -> NumericLiteralValue.fromBoolean(left.number != 0.0 && right.number.toInt() != 0, left.position)
+                DataType.FLOAT -> NumericLiteralValue.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: NumericLiteralValue, right: NumericLiteralValue): NumericLiteralValue {
+        if(left.type== DataType.UBYTE) {
+            if(right.type in IntegerDatatypes) {
+                return NumericLiteralValue(DataType.UBYTE, (left.number.toInt() xor (right.number.toInt() and 255)).toDouble(), left.position)
+            }
+        } else if(left.type== DataType.UWORD) {
+            if(right.type in IntegerDatatypes) {
+                return NumericLiteralValue(DataType.UWORD, (left.number.toInt() xor right.number.toInt()).toDouble(), left.position)
+            }
+        }
+        throw ExpressionError("cannot calculate $left ^ $right", left.position)
+    }
+
+    private fun bitwiseor(left: NumericLiteralValue, right: NumericLiteralValue): NumericLiteralValue {
+        if(left.type== DataType.UBYTE) {
+            if(right.type in IntegerDatatypes) {
+                return NumericLiteralValue(DataType.UBYTE, (left.number.toInt() or (right.number.toInt() and 255)).toDouble(), left.position)
+            }
+        } else if(left.type== DataType.UWORD) {
+            if(right.type in IntegerDatatypes) {
+                return NumericLiteralValue(DataType.UWORD, (left.number.toInt() or right.number.toInt()).toDouble(), left.position)
+            }
+        }
+        throw ExpressionError("cannot calculate $left | $right", left.position)
+    }
+
+    private fun bitwiseand(left: NumericLiteralValue, right: NumericLiteralValue): NumericLiteralValue {
+        if(left.type== DataType.UBYTE) {
+            if(right.type in IntegerDatatypes) {
+                return NumericLiteralValue(DataType.UBYTE, (left.number.toInt() and (right.number.toInt() and 255)).toDouble(), left.position)
+            }
+        } else if(left.type== DataType.UWORD) {
+            if(right.type in IntegerDatatypes) {
+                return NumericLiteralValue(DataType.UWORD, (left.number.toInt() and right.number.toInt()).toDouble(), left.position)
+            }
+        }
+        throw ExpressionError("cannot calculate $left & $right", left.position)
+    }
+
+    private fun power(left: NumericLiteralValue, right: NumericLiteralValue): NumericLiteralValue {
+        val error = "cannot calculate $left ** $right"
+        return when (left.type) {
+            in IntegerDatatypes -> when (right.type) {
+                in IntegerDatatypes -> NumericLiteralValue.optimalNumeric(left.number.toInt().toDouble().pow(right.number.toInt()), left.position)
+                DataType.FLOAT -> NumericLiteralValue(DataType.FLOAT, left.number.toInt().toDouble().pow(right.number), left.position)
+                else -> throw ExpressionError(error, left.position)
+            }
+            DataType.FLOAT -> when (right.type) {
+                in IntegerDatatypes -> NumericLiteralValue(DataType.FLOAT, left.number.pow(right.number.toInt()), left.position)
+                DataType.FLOAT -> NumericLiteralValue(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: NumericLiteralValue, right: NumericLiteralValue): NumericLiteralValue {
+        val error = "cannot add $left and $right"
+        return when (left.type) {
+            in IntegerDatatypes -> when (right.type) {
+                in IntegerDatatypes -> NumericLiteralValue.optimalInteger(left.number.toInt() + right.number.toInt(), left.position)
+                DataType.FLOAT -> NumericLiteralValue(DataType.FLOAT, left.number.toInt() + right.number, left.position)
+                else -> throw ExpressionError(error, left.position)
+            }
+            DataType.FLOAT -> when (right.type) {
+                in IntegerDatatypes -> NumericLiteralValue(DataType.FLOAT, left.number + right.number.toInt(), left.position)
+                DataType.FLOAT -> NumericLiteralValue(DataType.FLOAT, left.number + right.number, left.position)
+                else -> throw ExpressionError(error, left.position)
+            }
+            else -> throw ExpressionError(error, left.position)
+        }
+    }
+
+    private fun minus(left: NumericLiteralValue, right: NumericLiteralValue): NumericLiteralValue {
+        val error = "cannot subtract $left and $right"
+        return when (left.type) {
+            in IntegerDatatypes -> when (right.type) {
+                in IntegerDatatypes -> NumericLiteralValue.optimalInteger(left.number.toInt() - right.number.toInt(), left.position)
+                DataType.FLOAT -> NumericLiteralValue(DataType.FLOAT, left.number.toInt() - right.number, left.position)
+                else -> throw ExpressionError(error, left.position)
+            }
+            DataType.FLOAT -> when (right.type) {
+                in IntegerDatatypes -> NumericLiteralValue(DataType.FLOAT, left.number - right.number.toInt(), left.position)
+                DataType.FLOAT -> NumericLiteralValue(DataType.FLOAT, left.number - right.number, left.position)
+                else -> throw ExpressionError(error, left.position)
+            }
+            else -> throw ExpressionError(error, left.position)
+        }
+    }
+
+    private fun multiply(left: NumericLiteralValue, right: NumericLiteralValue): NumericLiteralValue {
+        val error = "cannot multiply ${left.type} and ${right.type}"
+        return when (left.type) {
+            in IntegerDatatypes -> when (right.type) {
+                in IntegerDatatypes -> NumericLiteralValue.optimalInteger(left.number.toInt() * right.number.toInt(), left.position)
+                DataType.FLOAT -> NumericLiteralValue(DataType.FLOAT, left.number.toInt() * right.number, left.position)
+                else -> throw ExpressionError(error, left.position)
+            }
+            DataType.FLOAT -> when (right.type) {
+                in IntegerDatatypes -> NumericLiteralValue(DataType.FLOAT, left.number * right.number.toInt(), left.position)
+                DataType.FLOAT -> NumericLiteralValue(DataType.FLOAT, left.number * right.number, left.position)
+                else -> throw ExpressionError(error, left.position)
+            }
+            else -> throw ExpressionError(error, left.position)
+        }
+    }
+
+    private fun divideByZeroError(pos: Position): Unit =
+            throw ExpressionError("division by zero", pos)
+
+    private fun divide(left: NumericLiteralValue, right: NumericLiteralValue): NumericLiteralValue {
+        val error = "cannot divide $left by $right"
+        return when (left.type) {
+            in IntegerDatatypes -> when (right.type) {
+                in IntegerDatatypes -> {
+                    if(right.number.toInt()==0) divideByZeroError(right.position)
+                    val result: Int = left.number.toInt() / right.number.toInt()
+                    NumericLiteralValue.optimalInteger(result, left.position)
+                }
+                DataType.FLOAT -> {
+                    if(right.number==0.0) divideByZeroError(right.position)
+                    NumericLiteralValue(DataType.FLOAT, left.number.toInt() / right.number, left.position)
+                }
+                else -> throw ExpressionError(error, left.position)
+            }
+            DataType.FLOAT -> when (right.type) {
+                in IntegerDatatypes -> {
+                    if(right.number.toInt()==0) divideByZeroError(right.position)
+                    NumericLiteralValue(DataType.FLOAT, left.number / right.number.toInt(), left.position)
+                }
+                DataType.FLOAT -> {
+                    if(right.number ==0.0) divideByZeroError(right.position)
+                    NumericLiteralValue(DataType.FLOAT, left.number / right.number, left.position)
+                }
+                else -> throw ExpressionError(error, left.position)
+            }
+            else -> throw ExpressionError(error, left.position)
+        }
+    }
+
+    private fun remainder(left: NumericLiteralValue, right: NumericLiteralValue): NumericLiteralValue {
+        val error = "cannot compute remainder of $left by $right"
+        return when (left.type) {
+            in IntegerDatatypes -> when (right.type) {
+                in IntegerDatatypes -> {
+                    if(right.number.toInt()==0) divideByZeroError(right.position)
+                    NumericLiteralValue.optimalNumeric(left.number.toInt().toDouble() % right.number.toInt().toDouble(), left.position)
+                }
+                DataType.FLOAT -> {
+                    if(right.number ==0.0) divideByZeroError(right.position)
+                    NumericLiteralValue(DataType.FLOAT, left.number.toInt() % right.number, left.position)
+                }
+                else -> throw ExpressionError(error, left.position)
+            }
+            DataType.FLOAT -> when (right.type) {
+                in IntegerDatatypes -> {
+                    if(right.number.toInt()==0) divideByZeroError(right.position)
+                    NumericLiteralValue(DataType.FLOAT, left.number % right.number.toInt(), left.position)
+                }
+                DataType.FLOAT -> {
+                    if(right.number ==0.0) divideByZeroError(right.position)
+                    NumericLiteralValue(DataType.FLOAT, left.number % right.number, left.position)
+                }
+                else -> throw ExpressionError(error, left.position)
+            }
+            else -> throw ExpressionError(error, left.position)
+        }
+    }
+}

codeOptimizers/src/prog8/optimizer/ConstantFoldingOptimizer.kt

@@ -0,0 +1,617 @@
+package prog8.optimizer
+
+import prog8.ast.Node
+import prog8.ast.Program
+import prog8.ast.base.*
+import prog8.ast.expressions.*
+import prog8.ast.statements.Assignment
+import prog8.ast.statements.ForLoop
+import prog8.ast.statements.VarDecl
+import prog8.ast.walk.AstWalker
+import prog8.ast.walk.IAstModification
+import kotlin.math.pow
+
+
+class ConstantFoldingOptimizer(private val program: Program) : AstWalker() {
+
+    override fun before(memread: DirectMemoryRead, parent: Node): Iterable<IAstModification> {
+        // @( &thing )  -->  thing
+        val addrOf = memread.addressExpression as? AddressOf
+        return if(addrOf!=null)
+            listOf(IAstModification.ReplaceNode(memread, addrOf.identifier, parent))
+        else
+            noModifications
+    }
+
+    override fun after(containment: ContainmentCheck, parent: Node): Iterable<IAstModification> {
+        val result = containment.constValue(program)
+        if(result!=null)
+            return listOf(IAstModification.ReplaceNode(containment, result, parent))
+        return noModifications
+    }
+
+    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 NumericLiteralValue) {
+            // 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,
+                                NumericLiteralValue.optimalInteger(-subexpr.number.toInt(), subexpr.position),
+                                parent))
+                    }
+                    DataType.FLOAT -> {
+                        listOf(IAstModification.ReplaceNode(expr,
+                                NumericLiteralValue(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,
+                                NumericLiteralValue(DataType.BYTE, subexpr.number.toInt().inv().toDouble(), subexpr.position),
+                                parent))
+                    }
+                    DataType.UBYTE -> {
+                        listOf(IAstModification.ReplaceNode(expr,
+                                NumericLiteralValue(DataType.UBYTE, (subexpr.number.toInt().inv() and 255).toDouble(), subexpr.position),
+                                parent))
+                    }
+                    DataType.WORD -> {
+                        listOf(IAstModification.ReplaceNode(expr,
+                                NumericLiteralValue(DataType.WORD, subexpr.number.toInt().inv().toDouble(), subexpr.position),
+                                parent))
+                    }
+                    DataType.UWORD -> {
+                        listOf(IAstModification.ReplaceNode(expr,
+                                NumericLiteralValue(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,
+                            NumericLiteralValue.fromBoolean(subexpr.number == 0.0, subexpr.position),
+                            parent))
+                }
+                else -> throw ExpressionError(expr.operator, subexpr.position)
+            }
+        }
+        return noModifications
+    }
+
+    /*
+     * Try to constfold a binary expression.
+     * Compile-time constant sub expressions will be evaluated on the spot.
+     * For instance, "9 * (4 + 2)" will be optimized into the integer literal 54.
+     *
+     * More complex stuff: reordering to group constants:
+     * If one of our operands is a Constant,
+     *   and the other operand is a Binary expression,
+     *   and one of ITS operands is a Constant,
+     *   and ITS other operand is NOT a Constant,
+     *   ...it may be possible to rewrite the expression to group the two Constants together,
+     *      to allow them to be const-folded away.
+     *
+     *  examples include:
+     *        (X / c1) * c2  ->  X / (c2/c1)
+     *        (X + c1) - c2  ->  X + (c1-c2)
+     */
+    override fun after(expr: BinaryExpression, parent: Node): Iterable<IAstModification> {
+        val leftconst = expr.left.constValue(program)
+        val rightconst = expr.right.constValue(program)
+        val modifications = mutableListOf<IAstModification>()
+
+        if(expr.operator=="==" && rightconst!=null) {
+            val leftExpr = expr.left as? BinaryExpression
+            if(leftExpr!=null) {
+                val leftRightConst = leftExpr.right.constValue(program)
+                if(leftRightConst!=null) {
+                    when (leftExpr.operator) {
+                        "+" -> {
+                            // X + С1 == C2  -->  X == C2 - C1
+                            val newRightConst = NumericLiteralValue(rightconst.type, rightconst.number - leftRightConst.number, rightconst.position)
+                            return listOf(
+                                IAstModification.ReplaceNode(leftExpr, leftExpr.left, expr),
+                                IAstModification.ReplaceNode(expr.right, newRightConst, expr)
+                            )
+                        }
+                        "-" -> {
+                            // X - С1 == C2  -->  X == C2 + C1
+                            val newRightConst = NumericLiteralValue(rightconst.type, rightconst.number + leftRightConst.number, rightconst.position)
+                            return listOf(
+                                IAstModification.ReplaceNode(leftExpr, leftExpr.left, expr),
+                                IAstModification.ReplaceNode(expr.right, newRightConst, expr)
+                            )
+                        }
+                    }
+                }
+            }
+        }
+
+        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 = NumericLiteralValue(leftDt, 0.0, expr.position)
+                    modifications += IAstModification.ReplaceNode(expr, value, parent)
+                }
+                1.0 -> {
+                    val value = NumericLiteralValue(leftDt, 1.0, expr.position)
+                    modifications += IAstModification.ReplaceNode(expr, value, parent)
+                }
+                2.0 -> {
+                    if(rightconst!=null) {
+                        val value = NumericLiteralValue(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 = NumericLiteralValue(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
+                rightconst != null -> expr.left as? BinaryExpression
+                else -> null
+            }
+            if (subExpr != null) {
+                val subleftconst = subExpr.left.constValue(program)
+                val subrightconst = subExpr.right.constValue(program)
+                if ((subleftconst != null && subrightconst == null) || (subleftconst == null && subrightconst != null)) {
+                    // try reordering.
+                    val change = groupTwoFloatConstsTogether(
+                        expr, subExpr,
+                        leftconst != null, rightconst != null,
+                        subleftconst != null, subrightconst != null
+                    )
+                    if (change != null)
+                        modifications += change
+                }
+            }
+        }
+
+        val evaluator = ConstExprEvaluator()
+
+        // const fold when both operands are a const
+        if(leftconst != null && rightconst != null) {
+            val result = evaluator.evaluate(leftconst, expr.operator, rightconst)
+            modifications += IAstModification.ReplaceNode(expr, result, parent)
+        }
+
+
+        val leftBinExpr = expr.left as? BinaryExpression
+        val rightBinExpr = expr.right as? BinaryExpression
+
+        if(leftBinExpr!=null && rightconst!=null) {
+            if(expr.operator=="+" || expr.operator=="-") {
+                if(leftBinExpr.operator in listOf("+", "-")) {
+                    val c2 = leftBinExpr.right.constValue(program)
+                    if(c2!=null) {
+                        // (X + C2) +/- rightConst  -->  X + (C2 +/- rightConst)
+                        // (X - C2) +/- rightConst  -->  X - (C2 +/- rightConst)   mind the flipped right operator
+                        val operator = if(leftBinExpr.operator=="+") expr.operator else if(expr.operator=="-") "+" else "-"
+                        val constants = BinaryExpression(c2, operator, rightconst, c2.position)
+                        val newExpr = BinaryExpression(leftBinExpr.left, leftBinExpr.operator, constants, expr.position)
+                        return listOf(IAstModification.ReplaceNode(expr, newExpr, parent))
+                    }
+                }
+            }
+            else if(expr.operator=="*") {
+                val c2 = leftBinExpr.right.constValue(program)
+                if(c2!=null) {
+                    if(leftBinExpr.operator=="*") {
+                        // (X * C2) * rightConst  -->  X * (rightConst*C2)
+                        val constants = BinaryExpression(rightconst, "*", c2, c2.position)
+                        val newExpr = BinaryExpression(leftBinExpr.left, "*", constants, expr.position)
+                        return listOf(IAstModification.ReplaceNode(expr, newExpr, parent))
+                    } else if (leftBinExpr.operator=="/") {
+                        //  (X / C2) * rightConst   -->  X * (rightConst/C2)
+                        val constants = BinaryExpression(rightconst, "/", c2, c2.position)
+                        val newExpr = BinaryExpression(leftBinExpr.left, "*", constants, expr.position)
+                        return listOf(IAstModification.ReplaceNode(expr, newExpr, parent))
+                    }
+                }
+            }
+            else if(expr.operator=="/") {
+                val c2 = leftBinExpr.right.constValue(program)
+                if(c2!=null && leftBinExpr.operator=="/") {
+                    // (X / C1) / C2   -->  X / (C1*C2)
+                    // NOTE: do not optimize  (X * C1) / C2   -->  X * (C1/C2)  because this causes precision loss on integers
+                    val constants = BinaryExpression(c2, "*", rightconst, c2.position)
+                    val newExpr = BinaryExpression(leftBinExpr.left, "/", constants, expr.position)
+                    return listOf(IAstModification.ReplaceNode(expr, newExpr, parent))
+                }
+            }
+        }
+
+        if(expr.operator=="+" || expr.operator=="-") {
+            if(leftBinExpr!=null && rightBinExpr!=null) {
+                val c1 = leftBinExpr.right.constValue(program)
+                val c2 = rightBinExpr.right.constValue(program)
+                if(leftBinExpr.operator=="+" && rightBinExpr.operator=="+") {
+                    if (c1 != null && c2 != null) {
+                        // (X + C1) <plusmin> (Y + C2)  =>  (X <plusmin> Y) + (C1 <plusmin> C2)
+                        val c3 = evaluator.evaluate(c1, expr.operator, c2)
+                        val xwithy = BinaryExpression(leftBinExpr.left, expr.operator, rightBinExpr.left, expr.position)
+                        val newExpr = BinaryExpression(xwithy, "+", c3, expr.position)
+                        modifications += IAstModification.ReplaceNode(expr, newExpr, parent)
+                    }
+                }
+                else if(leftBinExpr.operator=="-" && rightBinExpr.operator=="-") {
+                    if (c1 != null && c2 != null) {
+                        // (X - C1) <plusmin> (Y - C2)  =>  (X <plusmin> Y) - (C1 <plusmin> C2)
+                        val c3 = evaluator.evaluate(c1, expr.operator, c2)
+                        val xwithy = BinaryExpression(leftBinExpr.left, expr.operator, rightBinExpr.left, expr.position)
+                        val newExpr = BinaryExpression(xwithy, "-", c3, expr.position)
+                        modifications += IAstModification.ReplaceNode(expr, newExpr, parent)
+                    }
+                }
+                else if(leftBinExpr.operator=="*" && rightBinExpr.operator=="*"){
+                    if (c1 != null && c2 != null && c1==c2) {
+                        //(X * C) <plusmin> (Y * C)  =>  (X <plusmin> Y) * C
+                        val xwithy = BinaryExpression(leftBinExpr.left, expr.operator, rightBinExpr.left, expr.position)
+                        val newExpr = BinaryExpression(xwithy, "*", c1, expr.position)
+                        modifications += IAstModification.ReplaceNode(expr, newExpr, parent)
+                    }
+                }
+            }
+        }
+
+
+        return modifications
+    }
+
+    override fun after(array: ArrayLiteralValue, parent: Node): Iterable<IAstModification> {
+        // because constant folding can result in arrays that are now suddenly capable
+        // of telling the type of all their elements (for instance, when they contained -2 which
+        // was a prefix expression earlier), we recalculate the array's datatype.
+        if(array.type.isKnown)
+            return noModifications
+
+        // if the array literalvalue is inside an array vardecl, take the type from that
+        // otherwise infer it from the elements of the array
+        val vardeclType = (array.parent as? VarDecl)?.datatype
+        if(vardeclType!=null) {
+            val newArray = array.cast(vardeclType)
+            if (newArray != null && newArray != array)
+                return listOf(IAstModification.ReplaceNode(array, newArray, parent))
+        } else {
+            val arrayDt = array.guessDatatype(program)
+            if (arrayDt.isKnown) {
+                val newArray = array.cast(arrayDt.getOr(DataType.UNDEFINED))
+                if (newArray != null && newArray != array)
+                    return listOf(IAstModification.ReplaceNode(array, newArray, parent))
+            }
+        }
+
+        return noModifications
+    }
+
+    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))
+        else
+            noModifications
+    }
+
+    override fun after(forLoop: ForLoop, parent: Node): Iterable<IAstModification> {
+        fun adjustRangeDt(rangeFrom: NumericLiteralValue, targetDt: DataType, rangeTo: NumericLiteralValue, stepLiteral: NumericLiteralValue?, range: RangeExpression): RangeExpression? {
+            val fromCast = rangeFrom.cast(targetDt)
+            val toCast = rangeTo.cast(targetDt)
+            if(!fromCast.isValid || !toCast.isValid)
+                return null
+
+            val newStep =
+                if(stepLiteral!=null) {
+                    val stepCast = stepLiteral.cast(targetDt)
+                    if(stepCast.isValid)
+                        stepCast.valueOrZero()
+                    else
+                        range.step
+                } else {
+                    range.step
+                }
+
+            return RangeExpression(fromCast.valueOrZero(), toCast.valueOrZero(), newStep, range.position)
+        }
+
+        // adjust the datatype of a range expression in for loops to the loop variable.
+        val iterableRange = forLoop.iterable as? RangeExpression ?: return noModifications
+        val rangeFrom = iterableRange.from as? NumericLiteralValue
+        val rangeTo = iterableRange.to as? NumericLiteralValue
+        if(rangeFrom==null || rangeTo==null) return noModifications
+
+        val loopvar = forLoop.loopVar.targetVarDecl(program) ?: throw UndefinedSymbolError(forLoop.loopVar)
+
+        val stepLiteral = iterableRange.step as? NumericLiteralValue
+        when(loopvar.datatype) {
+            DataType.UBYTE -> {
+                if(rangeFrom.type!= DataType.UBYTE) {
+                    // attempt to translate the iterable into ubyte values
+                    val newIter = adjustRangeDt(rangeFrom, loopvar.datatype, rangeTo, stepLiteral, iterableRange)
+                    if(newIter!=null)
+                        return listOf(IAstModification.ReplaceNode(forLoop.iterable, newIter, forLoop))
+                }
+            }
+            DataType.BYTE -> {
+                if(rangeFrom.type!= DataType.BYTE) {
+                    // attempt to translate the iterable into byte values
+                    val newIter = adjustRangeDt(rangeFrom, loopvar.datatype, rangeTo, stepLiteral, iterableRange)
+                    if(newIter!=null)
+                        return listOf(IAstModification.ReplaceNode(forLoop.iterable, newIter, forLoop))
+                }
+            }
+            DataType.UWORD -> {
+                if(rangeFrom.type!= DataType.UWORD) {
+                    // attempt to translate the iterable into uword values
+                    val newIter = adjustRangeDt(rangeFrom, loopvar.datatype, rangeTo, stepLiteral, iterableRange)
+                    if(newIter!=null)
+                        return listOf(IAstModification.ReplaceNode(forLoop.iterable, newIter, forLoop))
+                }
+            }
+            DataType.WORD -> {
+                if(rangeFrom.type!= DataType.WORD) {
+                    // attempt to translate the iterable into word values
+                    val newIter = adjustRangeDt(rangeFrom, loopvar.datatype, rangeTo, stepLiteral, iterableRange)
+                    if(newIter!=null)
+                        return listOf(IAstModification.ReplaceNode(forLoop.iterable, newIter, forLoop))
+                }
+            }
+            else -> throw FatalAstException("invalid loopvar datatype $loopvar")
+        }
+
+        return noModifications
+    }
+
+    override fun after(decl: VarDecl, parent: Node): Iterable<IAstModification> {
+        val numval = decl.value as? NumericLiteralValue
+        if(decl.type== VarDeclType.CONST && numval!=null) {
+            val valueDt = numval.inferType(program)
+            if(valueDt isnot decl.datatype) {
+                val cast = numval.cast(decl.datatype)
+                if(cast.isValid)
+                    return listOf(IAstModification.ReplaceNode(numval, cast.valueOrZero(), decl))
+            }
+        }
+        return noModifications
+    }
+
+    private class ShuffleOperands(val expr: BinaryExpression,
+                                  val exprOperator: String?,
+                                  val subExpr: BinaryExpression,
+                                  val newExprLeft: Expression?,
+                                  val newExprRight: Expression?,
+                                  val newSubexprLeft: Expression?,
+                                  val newSubexprRight: Expression?
+                                  ): IAstModification {
+        override fun perform() {
+            if(exprOperator!=null) expr.operator = exprOperator
+            if(newExprLeft!=null) expr.left = newExprLeft
+            if(newExprRight!=null) expr.right = newExprRight
+            if(newSubexprLeft!=null) subExpr.left = newSubexprLeft
+            if(newSubexprRight!=null) subExpr.right = newSubexprRight
+        }
+    }
+
+    private fun groupTwoFloatConstsTogether(expr: BinaryExpression,
+       subExpr: BinaryExpression,
+       leftIsConst: Boolean,
+       rightIsConst: Boolean,
+       subleftIsConst: Boolean,
+       subrightIsConst: Boolean): IAstModification?
+    {
+        // 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
+        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) {
+                return if(leftIsConst) {
+                    if(subleftIsConst)
+                        ShuffleOperands(expr, null, subExpr, subExpr.right, null, null, expr.left)
+                    else
+                        ShuffleOperands(expr, null, subExpr, subExpr.left, null, expr.left, null)
+                } else {
+                    if(subleftIsConst)
+                        ShuffleOperands(expr, null, subExpr, null, subExpr.right, null, expr.right)
+                    else
+                        ShuffleOperands(expr, null, subExpr, null, subExpr.left, expr.right, null)
+                }
+            }
+
+            // If - or /,  we simetimes must reorder more, and flip operators (- -> +, / -> *)
+            if(expr.operator=="-" || expr.operator=="/") {
+                if(leftIsConst) {
+                    return if (subleftIsConst) {
+                        ShuffleOperands(expr, if (expr.operator == "-") "+" else "*", subExpr, subExpr.right, null, expr.left, subExpr.left)
+                    } else {
+                        IAstModification.ReplaceNode(expr,
+                                BinaryExpression(
+                                        BinaryExpression(expr.left, if (expr.operator == "-") "+" else "*", subExpr.right, subExpr.position),
+                                        expr.operator, subExpr.left, expr.position),
+                                expr.parent)
+                    }
+                } else {
+                    return if(subleftIsConst) {
+                        return ShuffleOperands(expr, null, subExpr, null, subExpr.right, null, expr.right)
+                    } else {
+                        IAstModification.ReplaceNode(expr,
+                                BinaryExpression(
+                                        subExpr.left, expr.operator,
+                                        BinaryExpression(expr.right, if (expr.operator == "-") "+" else "*", subExpr.right, subExpr.position),
+                                        expr.position),
+                                expr.parent)
+                    }
+                }
+            }
+            return null
+
+        }
+        else
+        {
+
+            if(expr.operator=="/" && subExpr.operator=="*") {
+                if(leftIsConst) {
+                    val change = if(subleftIsConst) {
+                        // C1/(C2*V) -> (C1/C2)/V
+                        BinaryExpression(
+                                BinaryExpression(expr.left, "/", subExpr.left, subExpr.position),
+                                "/",
+                                subExpr.right, expr.position)
+                    } else {
+                        // C1/(V*C2) -> (C1/C2)/V
+                        BinaryExpression(
+                                BinaryExpression(expr.left, "/", subExpr.right, subExpr.position),
+                                "/",
+                                subExpr.left, expr.position)
+                    }
+                    return IAstModification.ReplaceNode(expr, change, expr.parent)
+                } else {
+                    val change = if(subleftIsConst) {
+                        // (C1*V)/C2 -> (C1/C2)*V
+                        BinaryExpression(
+                                BinaryExpression(subExpr.left, "/", expr.right, subExpr.position),
+                                "*",
+                                subExpr.right, expr.position)
+                    } else {
+                        // (V*C1)/C2 -> (C1/C2)*V
+                        BinaryExpression(
+                                BinaryExpression(subExpr.right, "/", expr.right, subExpr.position),
+                                "*",
+                                subExpr.left, expr.position)
+                    }
+                    return IAstModification.ReplaceNode(expr, change, expr.parent)
+                }
+            }
+            else if(expr.operator=="*" && subExpr.operator=="/") {
+                if(leftIsConst) {
+                    val change = if(subleftIsConst) {
+                        // C1*(C2/V) -> (C1*C2)/V
+                        BinaryExpression(
+                                BinaryExpression(expr.left, "*", subExpr.left, subExpr.position),
+                                "/",
+                                subExpr.right, expr.position)
+                    } else {
+                        // C1*(V/C2) -> (C1/C2)*V
+                        BinaryExpression(
+                                BinaryExpression(expr.left, "/", subExpr.right, subExpr.position),
+                                "*",
+                                subExpr.left, expr.position)
+                    }
+                    return IAstModification.ReplaceNode(expr, change, expr.parent)
+                } else {
+                    val change = if(subleftIsConst) {
+                        // (C1/V)*C2 -> (C1*C2)/V
+                        BinaryExpression(
+                                BinaryExpression(subExpr.left, "*", expr.right, subExpr.position),
+                                "/",
+                                subExpr.right, expr.position)
+                    } else {
+                        // (V/C1)*C2 -> (C1/C2)*V
+                        BinaryExpression(
+                                BinaryExpression(expr.right, "/", subExpr.right, subExpr.position),
+                                "*",
+                                subExpr.left, expr.position)
+                    }
+                    return IAstModification.ReplaceNode(expr, change, expr.parent)
+                }
+            }
+            else if(expr.operator=="+" && subExpr.operator=="-") {
+                if(leftIsConst){
+                    val change = if(subleftIsConst){
+                        // c1+(c2-v)  ->  (c1+c2)-v
+                        BinaryExpression(
+                                BinaryExpression(expr.left, "+", subExpr.left, subExpr.position),
+                                "-",
+                                subExpr.right, expr.position)
+                    } else {
+                        // c1+(v-c2)  ->  v+(c1-c2)
+                        BinaryExpression(
+                                BinaryExpression(expr.left, "-", subExpr.right, subExpr.position),
+                                "+",
+                                subExpr.left, expr.position)
+                    }
+                    return IAstModification.ReplaceNode(expr, change, expr.parent)
+                } else {
+                    val change = if(subleftIsConst) {
+                        // (c1-v)+c2  ->  (c1+c2)-v
+                        BinaryExpression(
+                                BinaryExpression(subExpr.left, "+", expr.right, subExpr.position),
+                                "-",
+                                subExpr.right, expr.position)
+                    } else {
+                        // (v-c1)+c2  ->  v+(c2-c1)
+                        BinaryExpression(
+                                BinaryExpression(expr.right, "-", subExpr.right, subExpr.position),
+                                "+",
+                                subExpr.left, expr.position)
+                    }
+                    return IAstModification.ReplaceNode(expr, change, expr.parent)
+                }
+            }
+            else if(expr.operator=="-" && subExpr.operator=="+") {
+                if(leftIsConst) {
+                    val change = if(subleftIsConst) {
+                        // c1-(c2+v)  ->  (c1-c2)-v
+                        BinaryExpression(
+                                BinaryExpression(expr.left, "-", subExpr.left, subExpr.position),
+                                "-",
+                                subExpr.right, expr.position)
+                    } else {
+                        // c1-(v+c2)  ->  (c1-c2)-v
+                        BinaryExpression(
+                                BinaryExpression(expr.left, "-", subExpr.right, subExpr.position),
+                                "-",
+                                subExpr.left, expr.position)
+                    }
+                    return IAstModification.ReplaceNode(expr, change, expr.parent)
+                } else {
+                    val change = if(subleftIsConst) {
+                        // (c1+v)-c2  ->  v+(c1-c2)
+                        BinaryExpression(
+                                BinaryExpression(subExpr.left, "-", expr.right, subExpr.position),
+                                "+",
+                                subExpr.right, expr.position)
+                    } else {
+                        // (v+c1)-c2  ->  v+(c1-c2)
+                        BinaryExpression(
+                                BinaryExpression(subExpr.right, "-", expr.right, subExpr.position),
+                                "+",
+                                subExpr.left, expr.position)
+                    }
+                    return IAstModification.ReplaceNode(expr, change, expr.parent)
+                }
+            }
+
+            return null
+        }
+    }
+
+}

codeOptimizers/src/prog8/optimizer/ConstantIdentifierReplacer.kt

@@ -0,0 +1,234 @@
+package prog8.optimizer
+
+import prog8.ast.Node
+import prog8.ast.Program
+import prog8.ast.base.*
+import prog8.ast.expressions.*
+import prog8.ast.statements.*
+import prog8.ast.walk.AstWalker
+import prog8.ast.walk.IAstModification
+import prog8.compilerinterface.ICompilationTarget
+import prog8.compilerinterface.IErrorReporter
+
+// Fix up the literal value's type to match that of the vardecl
+//   (also check range literal operands types before they get expanded into arrays for instance)
+class VarConstantValueTypeAdjuster(private val program: Program, private val errors: IErrorReporter) : AstWalker() {
+
+    override fun after(decl: VarDecl, parent: Node): Iterable<IAstModification> {
+
+        if(decl.parent is AnonymousScope)
+            throw FatalAstException("vardecl may no longer occur in anonymousscope")
+
+        try {
+            val declConstValue = decl.value?.constValue(program)
+            if(declConstValue!=null && (decl.type==VarDeclType.VAR || decl.type==VarDeclType.CONST)
+                && declConstValue.type != decl.datatype) {
+                // avoid silent float roundings
+                if(decl.datatype in IntegerDatatypes && declConstValue.type==DataType.FLOAT) {
+                    errors.err("refused rounding of float to avoid loss of precision", decl.value!!.position)
+                } else {
+                    // cast the numeric literal to the appropriate datatype of the variable
+                    val cast = declConstValue.cast(decl.datatype)
+                    if (cast.isValid)
+                        return listOf(IAstModification.ReplaceNode(decl.value!!, cast.valueOrZero(), decl))
+                }
+            }
+        } catch (x: UndefinedSymbolError) {
+            errors.err(x.message, x.position)
+        }
+
+        return noModifications
+    }
+
+    override fun after(range: RangeExpression, parent: Node): Iterable<IAstModification> {
+        val from = range.from.constValue(program)?.number
+        val to = range.to.constValue(program)?.number
+        val step = range.step.constValue(program)?.number
+
+        if(from==null) {
+            if(!range.from.inferType(program).isInteger)
+                errors.err("range expression from value must be integer", range.from.position)
+        } else if(from-from.toInt()>0) {
+            errors.err("range expression from value must be integer", range.from.position)
+        }
+
+        if(to==null) {
+            if(!range.to.inferType(program).isInteger)
+                errors.err("range expression to value must be integer", range.to.position)
+        } else if(to-to.toInt()>0) {
+            errors.err("range expression to value must be integer", range.to.position)
+        }
+
+        if(step==null) {
+            if(!range.step.inferType(program).isInteger)
+                errors.err("range expression step value must be integer", range.step.position)
+        } else if(step-step.toInt()>0) {
+            errors.err("range expression step value must be integer", range.step.position)
+        }
+
+        return noModifications
+    }
+}
+
+
+// Replace all constant identifiers with their actual value,
+// and the array var initializer values and sizes.
+// This is needed because further constant optimizations depend on those.
+internal class ConstantIdentifierReplacer(private val program: Program, private val errors: IErrorReporter, private val compTarget: ICompilationTarget) : AstWalker() {
+
+    override fun after(identifier: IdentifierReference, parent: Node): Iterable<IAstModification> {
+        // replace identifiers that refer to const value, with the value itself
+        // if it's a simple type and if it's not a left hand side variable
+        if(identifier.parent is AssignTarget)
+            return noModifications
+        var forloop = identifier.parent as? ForLoop
+        if(forloop==null)
+            forloop = identifier.parent.parent as? ForLoop
+        if(forloop!=null && identifier===forloop.loopVar)
+            return noModifications
+
+        try {
+            val cval = identifier.constValue(program) ?: return noModifications
+            return when (cval.type) {
+                in NumericDatatypes -> listOf(
+                    IAstModification.ReplaceNode(
+                        identifier,
+                        NumericLiteralValue(cval.type, cval.number, identifier.position),
+                        identifier.parent
+                    )
+                )
+                in PassByReferenceDatatypes -> throw FatalAstException("pass-by-reference type should not be considered a constant")
+                else -> noModifications
+            }
+        } catch (x: UndefinedSymbolError) {
+            errors.err(x.message, x.position)
+            return noModifications
+        }
+    }
+
+    override fun before(decl: VarDecl, parent: Node): Iterable<IAstModification> {
+        // the initializer value can't refer to the variable itself (recursive definition)
+        if(decl.value?.referencesIdentifier(listOf(decl.name)) == true || decl.arraysize?.indexExpr?.referencesIdentifier(listOf(decl.name)) == true) {
+            errors.err("recursive var declaration", decl.position)
+            return noModifications
+        }
+
+        if(decl.type== VarDeclType.CONST || decl.type== VarDeclType.VAR) {
+            if(decl.isArray){
+                val arraysize = decl.arraysize
+                if(arraysize==null) {
+                    // for arrays that have no size specifier attempt to deduce the size
+                    val arrayval = decl.value as? ArrayLiteralValue
+                    if(arrayval!=null) {
+                        return listOf(IAstModification.SetExpression(
+                                { decl.arraysize = ArrayIndex(it, decl.position) },
+                                NumericLiteralValue.optimalInteger(arrayval.value.size, decl.position),
+                                decl
+                        ))
+                    }
+                }
+            }
+
+            when(decl.datatype) {
+                DataType.FLOAT -> {
+                    // vardecl: for scalar float vars, promote constant integer initialization values to floats
+                    val litval = decl.value as? NumericLiteralValue
+                    if (litval!=null && litval.type in IntegerDatatypes) {
+                        val newValue = NumericLiteralValue(DataType.FLOAT, litval.number, litval.position)
+                        return listOf(IAstModification.ReplaceNode(decl.value!!, newValue, decl))
+                    }
+                }
+                DataType.ARRAY_UB, DataType.ARRAY_B, DataType.ARRAY_UW, DataType.ARRAY_W -> {
+                    val rangeExpr = decl.value as? RangeExpression
+                    if(rangeExpr!=null) {
+                        // convert the initializer range expression to an actual array
+                        val declArraySize = decl.arraysize?.constIndex()
+                        if(declArraySize!=null && declArraySize!=rangeExpr.size())
+                            errors.err("range expression size (${rangeExpr.size()}) doesn't match declared array size ($declArraySize)", decl.value?.position!!)
+                        val constRange = rangeExpr.toConstantIntegerRange()
+                        if(constRange!=null) {
+                            val eltType = rangeExpr.inferType(program).getOr(DataType.UBYTE)
+                            val newValue = if(eltType in ByteDatatypes) {
+                                ArrayLiteralValue(InferredTypes.InferredType.known(decl.datatype),
+                                        constRange.map { NumericLiteralValue(eltType, it.toDouble(), decl.value!!.position) }.toTypedArray(),
+                                        position = decl.value!!.position)
+                            } else {
+                                ArrayLiteralValue(InferredTypes.InferredType.known(decl.datatype),
+                                        constRange.map { NumericLiteralValue(eltType, it.toDouble(), decl.value!!.position) }.toTypedArray(),
+                                        position = decl.value!!.position)
+                            }
+                            return listOf(IAstModification.ReplaceNode(decl.value!!, newValue, decl))
+                        }
+                    }
+                    val numericLv = decl.value as? NumericLiteralValue
+                    if(numericLv!=null && numericLv.type== DataType.FLOAT)
+                        errors.err("arraysize requires only integers here", numericLv.position)
+                    val size = decl.arraysize?.constIndex() ?: return noModifications
+                    if (rangeExpr==null && numericLv!=null) {
+                        // arraysize initializer is empty or a single int, and we know the size; create the arraysize.
+                        val fillvalue = numericLv.number.toInt()
+                        when(decl.datatype){
+                            DataType.ARRAY_UB -> {
+                                if(fillvalue !in 0..255)
+                                    errors.err("ubyte value overflow", numericLv.position)
+                            }
+                            DataType.ARRAY_B -> {
+                                if(fillvalue !in -128..127)
+                                    errors.err("byte value overflow", numericLv.position)
+                            }
+                            DataType.ARRAY_UW -> {
+                                if(fillvalue !in 0..65535)
+                                    errors.err("uword value overflow", numericLv.position)
+                            }
+                            DataType.ARRAY_W -> {
+                                if(fillvalue !in -32768..32767)
+                                    errors.err("word value overflow", numericLv.position)
+                            }
+                            else -> {}
+                        }
+                        // create the array itself, filled with the fillvalue.
+                        val array = Array(size) {fillvalue}.map { NumericLiteralValue(ArrayToElementTypes.getValue(decl.datatype), it.toDouble(), numericLv.position) }.toTypedArray<Expression>()
+                        val refValue = ArrayLiteralValue(InferredTypes.InferredType.known(decl.datatype), array, position = numericLv.position)
+                        return listOf(IAstModification.ReplaceNode(decl.value!!, refValue, decl))
+                    }
+                }
+                DataType.ARRAY_F -> {
+                    val rangeExpr = decl.value as? RangeExpression
+                    if(rangeExpr!=null) {
+                        // convert the initializer range expression to an actual array of floats
+                        val declArraySize = decl.arraysize?.constIndex()
+                        if(declArraySize!=null && declArraySize!=rangeExpr.size())
+                            errors.err("range expression size (${rangeExpr.size()}) doesn't match declared array size ($declArraySize)", decl.value?.position!!)
+                        val constRange = rangeExpr.toConstantIntegerRange()
+                        if(constRange!=null) {
+                            val newValue = ArrayLiteralValue(InferredTypes.InferredType.known(DataType.ARRAY_F),
+                                    constRange.map { NumericLiteralValue(DataType.FLOAT, it.toDouble(), decl.value!!.position) }.toTypedArray(),
+                                    position = decl.value!!.position)
+                            return listOf(IAstModification.ReplaceNode(decl.value!!, newValue, decl))
+                        }
+                    }
+
+                    val numericLv = decl.value as? NumericLiteralValue
+                    val size = decl.arraysize?.constIndex() ?: return noModifications
+                    if(rangeExpr==null && numericLv!=null) {
+                        // arraysize initializer is a single int, and we know the size.
+                        val fillvalue = numericLv.number
+                        if (fillvalue < compTarget.machine.FLOAT_MAX_NEGATIVE || fillvalue > compTarget.machine.FLOAT_MAX_POSITIVE)
+                            errors.err("float value overflow", numericLv.position)
+                        else {
+                            // create the array itself, filled with the fillvalue.
+                            val array = Array(size) {fillvalue}.map { NumericLiteralValue(DataType.FLOAT, it, numericLv.position) }.toTypedArray<Expression>()
+                            val refValue = ArrayLiteralValue(InferredTypes.InferredType.known(DataType.ARRAY_F), array, position = numericLv.position)
+                            return listOf(IAstModification.ReplaceNode(decl.value!!, refValue, decl))
+                        }
+                    }
+                }
+                else -> {
+                    // nothing to do for this type
+                }
+            }
+        }
+
+        return noModifications
+    }
+}

codeOptimizers/src/prog8/optimizer/ExpressionSimplifier.kt

@@ -0,0 +1,760 @@
+package prog8.optimizer
+
+import prog8.ast.IStatementContainer
+import prog8.ast.Node
+import prog8.ast.Program
+import prog8.ast.base.DataType
+import prog8.ast.base.FatalAstException
+import prog8.ast.base.IntegerDatatypes
+import prog8.ast.base.NumericDatatypes
+import prog8.ast.expressions.*
+import prog8.ast.statements.*
+import prog8.ast.walk.AstWalker
+import prog8.ast.walk.IAstModification
+import prog8.compilerinterface.IErrorReporter
+import kotlin.math.abs
+import kotlin.math.log2
+import kotlin.math.pow
+
+/*
+    todo add more peephole expression optimizations
+
+    Investigate what optimizations binaryen has, also see  https://egorbo.com/peephole-optimizations.html
+
+ */
+
+
+class ExpressionSimplifier(private val program: Program, private val errors: IErrorReporter) : AstWalker() {
+    private val powersOfTwo = (1..16).map { (2.0).pow(it) }.toSet()
+    private val negativePowersOfTwo = powersOfTwo.map { -it }.toSet()
+
+    override fun after(typecast: TypecastExpression, parent: Node): Iterable<IAstModification> {
+        val mods = mutableListOf<IAstModification>()
+
+        // try to statically convert a literal value into one of the desired type
+        val literal = typecast.expression as? NumericLiteralValue
+        if (literal != null) {
+            val newLiteral = literal.cast(typecast.type)
+            if (newLiteral.isValid && newLiteral.valueOrZero() !== literal)
+                mods += IAstModification.ReplaceNode(typecast.expression, newLiteral.valueOrZero(), typecast)
+        }
+
+        // remove redundant nested typecasts
+        val subTypecast = typecast.expression as? TypecastExpression
+        if (subTypecast != null) {
+            // remove the sub-typecast if its datatype is larger than the outer typecast
+            if(subTypecast.type largerThan typecast.type) {
+                mods += IAstModification.ReplaceNode(typecast.expression, subTypecast.expression, typecast)
+            }
+        } else {
+            if (typecast.expression.inferType(program) istype typecast.type) {
+                // remove duplicate cast
+                mods += IAstModification.ReplaceNode(typecast, typecast.expression, parent)
+            }
+        }
+
+        return mods
+    }
+
+    override fun after(ifElse: IfElse, parent: Node): Iterable<IAstModification> {
+        val truepart = ifElse.truepart
+        val elsepart = ifElse.elsepart
+        if(truepart.isNotEmpty() && elsepart.isNotEmpty()) {
+            if(truepart.statements.singleOrNull() is Jump) {
+                return listOf(
+                    IAstModification.InsertAfter(ifElse, elsepart, parent as IStatementContainer),
+                    IAstModification.ReplaceNode(elsepart, AnonymousScope(mutableListOf(), elsepart.position), ifElse)
+                )
+            }
+            if(elsepart.statements.singleOrNull() is Jump) {
+                val invertedCondition = invertCondition(ifElse.condition)
+                if(invertedCondition!=null) {
+                    return listOf(
+                        IAstModification.ReplaceNode(ifElse.condition, invertedCondition, ifElse),
+                        IAstModification.InsertAfter(ifElse, truepart, parent as IStatementContainer),
+                        IAstModification.ReplaceNode(elsepart, AnonymousScope(mutableListOf(), elsepart.position), ifElse),
+                        IAstModification.ReplaceNode(truepart, elsepart, ifElse)
+                    )
+                }
+            }
+        }
+        return noModifications
+    }
+
+    override fun after(expr: BinaryExpression, parent: Node): Iterable<IAstModification> {
+        val leftVal = expr.left.constValue(program)
+        val rightVal = expr.right.constValue(program)
+
+        val leftIDt = expr.left.inferType(program)
+        val rightIDt = expr.right.inferType(program)
+        if (!leftIDt.isKnown || !rightIDt.isKnown)
+            throw FatalAstException("can't determine datatype of both expression operands $expr")
+
+        // ConstValue <associativeoperator> X -->  X <associativeoperator> ConstValue
+        if (leftVal != null && expr.operator in AssociativeOperators && rightVal == null)
+            return listOf(IAstModification.SwapOperands(expr))
+
+        // NonBinaryExpression  <associativeoperator>  BinaryExpression  -->  BinaryExpression  <associativeoperator>  NonBinaryExpression
+        if (expr.operator in AssociativeOperators && expr.left !is BinaryExpression && expr.right is BinaryExpression) {
+            if(parent !is Assignment || !(expr.left isSameAs parent.target))
+                return listOf(IAstModification.SwapOperands(expr))
+        }
+
+        // X + (-A)  -->  X - A
+        if (expr.operator == "+" && (expr.right as? PrefixExpression)?.operator == "-") {
+            return listOf(IAstModification.ReplaceNode(
+                    expr,
+                    BinaryExpression(expr.left, "-", (expr.right as PrefixExpression).expression, expr.position),
+                    parent
+            ))
+        }
+
+        // (-A) + X  -->  X - A
+        if (expr.operator == "+" && (expr.left as? PrefixExpression)?.operator == "-") {
+            return listOf(IAstModification.ReplaceNode(
+                    expr,
+                    BinaryExpression(expr.right, "-", (expr.left as PrefixExpression).expression, expr.position),
+                    parent
+            ))
+        }
+
+        // X - (-A)  -->  X + A
+        if (expr.operator == "-" && (expr.right as? PrefixExpression)?.operator == "-") {
+            return listOf(IAstModification.ReplaceNode(
+                    expr,
+                    BinaryExpression(expr.left, "+", (expr.right as PrefixExpression).expression, expr.position),
+                    parent
+            ))
+        }
+
+        val leftDt = leftIDt.getOr(DataType.UNDEFINED)
+        val rightDt = rightIDt.getOr(DataType.UNDEFINED)
+
+        if (expr.operator == "+" || expr.operator == "-"
+                && leftVal == null && rightVal == null
+                && leftDt in NumericDatatypes && rightDt in NumericDatatypes) {
+            val leftBinExpr = expr.left as? BinaryExpression
+            val rightBinExpr = expr.right as? BinaryExpression
+            if (leftBinExpr?.operator == "*") {
+                if (expr.operator == "+") {
+                    // Y*X + X  ->  X*(Y + 1)
+                    // X*Y + X  ->  X*(Y + 1)
+                    val x = expr.right
+                    val y = determineY(x, leftBinExpr)
+                    if (y != null) {
+                        val yPlus1 = BinaryExpression(y, "+", NumericLiteralValue(leftDt, 1.0, y.position), y.position)
+                        val newExpr = BinaryExpression(x, "*", yPlus1, x.position)
+                        return listOf(IAstModification.ReplaceNode(expr, newExpr, parent))
+                    }
+                } else {
+                    // Y*X - X  ->  X*(Y - 1)
+                    // X*Y - X  ->  X*(Y - 1)
+                    val x = expr.right
+                    val y = determineY(x, leftBinExpr)
+                    if (y != null) {
+                        val yMinus1 = BinaryExpression(y, "-", NumericLiteralValue(leftDt, 1.0, y.position), y.position)
+                        val newExpr = BinaryExpression(x, "*", yMinus1, x.position)
+                        return listOf(IAstModification.ReplaceNode(expr, newExpr, parent))
+                    }
+                }
+            } else if (rightBinExpr?.operator == "*") {
+                if (expr.operator == "+") {
+                    // X + Y*X  ->  X*(Y + 1)
+                    // X + X*Y  ->  X*(Y + 1)
+                    val x = expr.left
+                    val y = determineY(x, rightBinExpr)
+                    if (y != null) {
+                        val yPlus1 = BinaryExpression(y, "+", NumericLiteralValue.optimalInteger(1, y.position), y.position)
+                        val newExpr = BinaryExpression(x, "*", yPlus1, x.position)
+                        return listOf(IAstModification.ReplaceNode(expr, newExpr, parent))
+                    }
+                }
+            }
+        }
+
+        if(leftDt!=DataType.FLOAT && expr.operator == ">=" && rightVal?.number == 1.0) {
+            // for integers: x >= 1  -->  x > 0
+            expr.operator = ">"
+            return listOf(IAstModification.ReplaceNode(expr.right, NumericLiteralValue.optimalInteger(0, expr.right.position), expr))
+        }
+
+        if(expr.operator == ">=" && rightVal?.number == 0.0) {
+            if (leftDt == DataType.UBYTE || leftDt == DataType.UWORD) {
+                // unsigned >= 0 --> true
+                return listOf(IAstModification.ReplaceNode(expr, NumericLiteralValue.fromBoolean(true, expr.position), parent))
+            }
+        }
+
+        if(leftDt!=DataType.FLOAT && expr.operator == "<" && rightVal?.number == 1.0) {
+            // for integers: x < 1  -->  x <= 0
+            expr.operator = "<="
+            return listOf(IAstModification.ReplaceNode(expr.right, NumericLiteralValue.optimalInteger(0, expr.right.position), expr))
+        }
+
+        if(expr.operator == "<" && rightVal?.number == 0.0) {
+            if (leftDt == DataType.UBYTE || leftDt == DataType.UWORD) {
+                // unsigned < 0 --> false
+                return listOf(IAstModification.ReplaceNode(expr, NumericLiteralValue.fromBoolean(false, expr.position), parent))
+            }
+        }
+
+        // simplify when a term is constant and directly determines the outcome
+        val constTrue = NumericLiteralValue.fromBoolean(true, expr.position)
+        val constFalse = NumericLiteralValue.fromBoolean(false, expr.position)
+        val newExpr: Expression? = when (expr.operator) {
+            "or" -> {
+                when {
+                    leftVal != null && leftVal.asBooleanValue || rightVal != null && rightVal.asBooleanValue -> constTrue
+                    leftVal != null && !leftVal.asBooleanValue -> expr.right
+                    rightVal != null && !rightVal.asBooleanValue -> expr.left
+                    else -> null
+                }
+            }
+            "and" -> {
+                when {
+                    leftVal != null && !leftVal.asBooleanValue || rightVal != null && !rightVal.asBooleanValue -> constFalse
+                    leftVal != null && leftVal.asBooleanValue -> expr.right
+                    rightVal != null && rightVal.asBooleanValue -> expr.left
+                    else -> null
+                }
+            }
+            "xor" -> {
+                when {
+                    leftVal != null && !leftVal.asBooleanValue -> expr.right
+                    rightVal != null && !rightVal.asBooleanValue -> expr.left
+                    leftVal != null && leftVal.asBooleanValue -> PrefixExpression("not", expr.right, expr.right.position)
+                    rightVal != null && rightVal.asBooleanValue -> PrefixExpression("not", expr.left, expr.left.position)
+                    else -> null
+                }
+            }
+            "|" -> {
+                when {
+                    leftVal?.number==0.0 -> expr.right
+                    rightVal?.number==0.0 -> expr.left
+                    rightIDt.isBytes && rightVal?.number==255.0 -> NumericLiteralValue(DataType.UBYTE, 255.0, rightVal.position)
+                    rightIDt.isWords && rightVal?.number==65535.0 -> NumericLiteralValue(DataType.UWORD, 65535.0, rightVal.position)
+                    leftIDt.isBytes && leftVal?.number==255.0 -> NumericLiteralValue(DataType.UBYTE, 255.0, leftVal.position)
+                    leftIDt.isWords && leftVal?.number==65535.0 -> NumericLiteralValue(DataType.UWORD, 65535.0, leftVal.position)
+                    else -> null
+                }
+            }
+            "^" -> {
+                when {
+                    leftVal?.number==0.0 -> expr.right
+                    rightVal?.number==0.0 -> expr.left
+                    rightIDt.isBytes && rightVal?.number==255.0 -> PrefixExpression("~", expr.left, expr.left.position)
+                    rightIDt.isWords && rightVal?.number==65535.0 -> PrefixExpression("~", expr.left, expr.left.position)
+                    leftIDt.isBytes && leftVal?.number==255.0 -> PrefixExpression("~", expr.right, expr.right.position)
+                    leftIDt.isWords && leftVal?.number==65535.0 -> PrefixExpression("~", expr.right, expr.right.position)
+                    else -> null
+                }
+            }
+            "&" -> {
+                when {
+                    leftVal?.number==0.0  -> constFalse
+                    rightVal?.number==0.0 -> constFalse
+                    rightIDt.isBytes && rightVal?.number==255.0 -> expr.left
+                    rightIDt.isWords && rightVal?.number==65535.0 -> expr.left
+                    leftIDt.isBytes && leftVal?.number==255.0 -> expr.right
+                    leftIDt.isWords && leftVal?.number==65535.0 -> expr.right
+                    else -> null
+                }
+            }
+            "*" -> optimizeMultiplication(expr, leftVal, rightVal)
+            "/" -> optimizeDivision(expr, leftVal, rightVal)
+            "+" -> optimizeAdd(expr, leftVal, rightVal)
+            "-" -> optimizeSub(expr, leftVal, rightVal)
+            "**" -> optimizePower(expr, leftVal, rightVal)
+            "%" -> optimizeRemainder(expr, leftVal, rightVal)
+            ">>" -> optimizeShiftRight(expr, rightVal)
+            "<<" -> optimizeShiftLeft(expr, rightVal)
+            else -> null
+        }
+
+        if(newExpr != null)
+            return listOf(IAstModification.ReplaceNode(expr, newExpr, parent))
+
+        return noModifications
+    }
+
+    override fun after(functionCallExpr: FunctionCallExpression, parent: Node): Iterable<IAstModification> {
+        if(functionCallExpr.target.nameInSource == listOf("lsb")) {
+            val arg = functionCallExpr.args[0]
+            if(arg is TypecastExpression) {
+                val valueDt = arg.expression.inferType(program)
+                if (valueDt istype DataType.BYTE || valueDt istype DataType.UBYTE) {
+                    // useless lsb() of byte value that was typecasted to word
+                    return listOf(IAstModification.ReplaceNode(functionCallExpr, arg.expression, parent))
+                }
+            } else {
+                val argDt = arg.inferType(program)
+                if (argDt istype DataType.BYTE || argDt istype DataType.UBYTE) {
+                    // useless lsb() of byte value
+                    return listOf(IAstModification.ReplaceNode(functionCallExpr, arg, parent))
+                }
+            }
+        }
+        else if(functionCallExpr.target.nameInSource == listOf("msb")) {
+            val arg = functionCallExpr.args[0]
+            if(arg is TypecastExpression) {
+                val valueDt = arg.expression.inferType(program)
+                if (valueDt istype DataType.BYTE || valueDt istype DataType.UBYTE) {
+                    // useless msb() of byte value that was typecasted to word, replace with 0
+                    return listOf(IAstModification.ReplaceNode(
+                            functionCallExpr,
+                            NumericLiteralValue(valueDt.getOr(DataType.UBYTE), 0.0, arg.expression.position),
+                            parent))
+                }
+            } else {
+                val argDt = arg.inferType(program)
+                if (argDt istype DataType.BYTE || argDt istype DataType.UBYTE) {
+                    // useless msb() of byte value, replace with 0
+                    return listOf(IAstModification.ReplaceNode(
+                            functionCallExpr,
+                            NumericLiteralValue(argDt.getOr(DataType.UBYTE), 0.0, arg.position),
+                            parent))
+                }
+            }
+        }
+
+        return noModifications
+    }
+
+    override fun after(containment: ContainmentCheck, parent: Node): Iterable<IAstModification> {
+        val range = containment.iterable as? RangeExpression
+        if(range!=null && range.step.constValue(program)?.number==1.0) {
+            val from = range.from.constValue(program)
+            val to = range.to.constValue(program)
+            val value = containment.element
+            if(from!=null && to!=null && value.isSimple) {
+                if(to.number-from.number>6.0) {
+                    // replace containment test with X>=from and X<=to
+                    val left = BinaryExpression(value, ">=", from, containment.position)
+                    val right = BinaryExpression(value.copy(), "<=", to, containment.position)
+                    val comparison = BinaryExpression(left, "and", right, containment.position)
+                    return listOf(IAstModification.ReplaceNode(containment, comparison, parent))
+                }
+            }
+        }
+        return noModifications
+    }
+
+    override fun after(pipeExpr: PipeExpression, parent: Node): Iterable<IAstModification> {
+        val expressions = pipeExpr.expressions
+        val firstValue = expressions.first()
+        if(firstValue.isSimple) {
+            val funcname = expressions[1] as IdentifierReference
+            val first = FunctionCallExpression(funcname.copy(), mutableListOf(firstValue), firstValue.position)
+            val newExprs = mutableListOf<Expression>(first)
+            newExprs.addAll(expressions.drop(2))
+            return listOf(IAstModification.ReplaceNode(pipeExpr, PipeExpression(newExprs, pipeExpr.position), parent))
+        }
+        val singleExpr = expressions.singleOrNull()
+        if(singleExpr!=null) {
+            val callExpr = singleExpr as FunctionCallExpression
+            val call = FunctionCallExpression(callExpr.target, callExpr.args, callExpr.position)
+            return listOf(IAstModification.ReplaceNode(pipeExpr, call, parent))
+        }
+        return noModifications
+    }
+
+    override fun after(pipe: Pipe, parent: Node): Iterable<IAstModification> {
+        val expressions = pipe.expressions
+        val firstValue = expressions.first()
+        if(firstValue.isSimple) {
+            val funcname = expressions[1] as IdentifierReference
+            val first = FunctionCallExpression(funcname.copy(), mutableListOf(firstValue), firstValue.position)
+            val newExprs = mutableListOf<Expression>(first)
+            newExprs.addAll(expressions.drop(2))
+            return listOf(IAstModification.ReplaceNode(pipe, Pipe(newExprs, pipe.position), parent))
+        }
+        val singleExpr = expressions.singleOrNull()
+        if(singleExpr!=null) {
+            val callExpr = singleExpr as FunctionCallExpression
+            val call = FunctionCallStatement(callExpr.target, callExpr.args, true, callExpr.position)
+            return listOf(IAstModification.ReplaceNode(pipe, call, parent))
+        }
+        return noModifications
+    }
+
+    private fun determineY(x: Expression, subBinExpr: BinaryExpression): Expression? {
+        return when {
+            subBinExpr.left isSameAs x -> subBinExpr.right
+            subBinExpr.right isSameAs x -> subBinExpr.left
+            else -> null
+        }
+    }
+
+    private fun optimizeAdd(expr: BinaryExpression, leftVal: NumericLiteralValue?, rightVal: NumericLiteralValue?): Expression? {
+        if(expr.left.isSameAs(expr.right)) {
+            // optimize X+X into X *2
+            expr.operator = "*"
+            expr.right = NumericLiteralValue.optimalInteger(2, expr.right.position)
+            expr.right.linkParents(expr)
+            return expr
+        }
+
+        if (leftVal == null && rightVal == null)
+            return null
+
+        val (expr2, _, rightVal2) = reorderAssociativeWithConstant(expr, leftVal)
+        if (rightVal2 != null) {
+            // right value is a constant, see if we can optimize
+            val rightConst: NumericLiteralValue = rightVal2
+            when (rightConst.number) {
+                0.0 -> {
+                    // left
+                    return expr2.left
+                }
+            }
+        }
+        // no need to check for left val constant (because of associativity)
+
+        val rnum = rightVal?.number
+        if(rnum!=null && rnum<0.0) {
+            expr.operator = "-"
+            expr.right = NumericLiteralValue(rightVal.type, -rnum, rightVal.position)
+            return expr
+        }
+
+        return null
+    }
+
+    private fun optimizeSub(expr: BinaryExpression, leftVal: NumericLiteralValue?, rightVal: NumericLiteralValue?): Expression? {
+        if(expr.left.isSameAs(expr.right)) {
+            // optimize X-X into 0
+            return NumericLiteralValue.optimalInteger(0, expr.position)
+        }
+
+        if (leftVal == null && rightVal == null)
+            return null
+
+        if (rightVal != null) {
+            // right value is a constant, see if we can optimize
+            val rnum = rightVal.number
+            if (rnum == 0.0) {
+                // left
+                return expr.left
+            }
+
+            if(rnum<0.0) {
+                expr.operator = "+"
+                expr.right = NumericLiteralValue(rightVal.type, -rnum, rightVal.position)
+                return expr
+            }
+        }
+        if (leftVal != null) {
+            // left value is a constant, see if we can optimize
+            when (leftVal.number) {
+                0.0 -> {
+                    // -right
+                    return PrefixExpression("-", expr.right, expr.position)
+                }
+            }
+        }
+
+
+        return null
+    }
+
+    private fun optimizePower(expr: BinaryExpression, leftVal: NumericLiteralValue?, rightVal: NumericLiteralValue?): Expression? {
+        if (leftVal == null && rightVal == null)
+            return null
+
+        if (rightVal != null) {
+            // right value is a constant, see if we can optimize
+            val rightConst: NumericLiteralValue = rightVal
+            when (rightConst.number) {
+                -3.0 -> {
+                    // -1/(left*left*left)
+                    return BinaryExpression(NumericLiteralValue(DataType.FLOAT, -1.0, expr.position), "/",
+                            BinaryExpression(expr.left, "*", BinaryExpression(expr.left, "*", expr.left, expr.position), expr.position),
+                            expr.position)
+                }
+                -2.0 -> {
+                    // -1/(left*left)
+                    return BinaryExpression(NumericLiteralValue(DataType.FLOAT, -1.0, expr.position), "/",
+                            BinaryExpression(expr.left, "*", expr.left, expr.position),
+                            expr.position)
+                }
+                -1.0 -> {
+                    // -1/left
+                    return BinaryExpression(NumericLiteralValue(DataType.FLOAT, -1.0, expr.position), "/",
+                            expr.left, expr.position)
+                }
+                0.0 -> {
+                    // 1
+                    return NumericLiteralValue(rightConst.type, 1.0, expr.position)
+                }
+                0.5 -> {
+                    // sqrt(left)
+                    return FunctionCallExpression(IdentifierReference(listOf("sqrt"), expr.position), mutableListOf(expr.left), expr.position)
+                }
+                1.0 -> {
+                    // left
+                    return expr.left
+                }
+                2.0 -> {
+                    // left*left
+                    return BinaryExpression(expr.left, "*", expr.left, expr.position)
+                }
+                3.0 -> {
+                    // left*left*left
+                    return BinaryExpression(expr.left, "*", BinaryExpression(expr.left, "*", expr.left, expr.position), expr.position)
+                }
+            }
+        }
+        if (leftVal != null) {
+            // left value is a constant, see if we can optimize
+            when (leftVal.number) {
+                -1.0 -> {
+                    // -1
+                    return NumericLiteralValue(DataType.FLOAT, -1.0, expr.position)
+                }
+                0.0 -> {
+                    // 0
+                    return NumericLiteralValue(leftVal.type, 0.0, expr.position)
+                }
+                1.0 -> {
+                    //1
+                    return NumericLiteralValue(leftVal.type, 1.0, expr.position)
+                }
+
+            }
+        }
+
+        return null
+    }
+
+    private fun optimizeRemainder(expr: BinaryExpression, leftVal: NumericLiteralValue?, rightVal: NumericLiteralValue?): Expression? {
+        if (leftVal == null && rightVal == null)
+            return null
+
+        // simplify assignments  A = B <operator> C
+
+        val cv = rightVal?.number?.toInt()?.toDouble()
+        when (expr.operator) {
+            "%" -> {
+                if (cv == 1.0) {
+                    val idt = expr.inferType(program)
+                    if(!idt.isKnown)
+                        throw FatalAstException("unknown dt")
+                    return NumericLiteralValue(idt.getOr(DataType.UNDEFINED), 0.0, expr.position)
+                } else if (cv in powersOfTwo) {
+                    expr.operator = "&"
+                    expr.right = NumericLiteralValue.optimalInteger(cv!!.toInt()-1, expr.position)
+                    return null
+                }
+            }
+        }
+        return null
+
+    }
+
+    private fun optimizeDivision(expr: BinaryExpression, leftVal: NumericLiteralValue?, rightVal: NumericLiteralValue?): Expression? {
+        if (leftVal == null && rightVal == null)
+            return null
+
+        // cannot shuffle assiciativity with division!
+        if (rightVal != null) {
+            // right value is a constant, see if we can optimize
+            val rightConst: NumericLiteralValue = rightVal
+            val cv = rightConst.number
+            val leftIDt = expr.left.inferType(program)
+            if (!leftIDt.isKnown)
+                return null
+            val leftDt = leftIDt.getOr(DataType.UNDEFINED)
+            when (cv) {
+                -1.0 -> {
+                    //  '/' -> -left
+                    if (expr.operator == "/") {
+                        return PrefixExpression("-", expr.left, expr.position)
+                    }
+                }
+                1.0 -> {
+                    //  '/' -> left
+                    if (expr.operator == "/") {
+                        return expr.left
+                    }
+                }
+                in powersOfTwo -> {
+                    if (leftDt in IntegerDatatypes) {
+                        // divided by a power of two => shift right
+                        val numshifts = log2(cv).toInt()
+                        return BinaryExpression(expr.left, ">>", NumericLiteralValue.optimalInteger(numshifts, expr.position), expr.position)
+                    }
+                }
+                in negativePowersOfTwo -> {
+                    if (leftDt in IntegerDatatypes) {
+                        // divided by a negative power of two => negate, then shift right
+                        val numshifts = log2(-cv).toInt()
+                        return BinaryExpression(PrefixExpression("-", expr.left, expr.position), ">>", NumericLiteralValue.optimalInteger(numshifts, expr.position), expr.position)
+                    }
+                }
+            }
+
+            if (leftDt == DataType.UBYTE) {
+                if (abs(rightConst.number) >= 256.0) {
+                    return NumericLiteralValue(DataType.UBYTE, 0.0, expr.position)
+                }
+            } else if (leftDt == DataType.UWORD) {
+                if (abs(rightConst.number) >= 65536.0) {
+                    return NumericLiteralValue(DataType.UBYTE, 0.0, expr.position)
+                }
+            }
+        }
+
+        if (leftVal != null) {
+            // left value is a constant, see if we can optimize
+            when (leftVal.number) {
+                0.0 -> {
+                    // 0
+                    return NumericLiteralValue(leftVal.type, 0.0, expr.position)
+                }
+            }
+        }
+
+        return null
+    }
+
+    private fun optimizeMultiplication(expr: BinaryExpression, leftVal: NumericLiteralValue?, rightVal: NumericLiteralValue?): Expression? {
+        if (leftVal == null && rightVal == null)
+            return null
+
+        val (expr2, _, rightVal2) = reorderAssociativeWithConstant(expr, leftVal)
+        if (rightVal2 != null) {
+            // right value is a constant, see if we can optimize
+            val leftValue: Expression = expr2.left
+            val rightConst: NumericLiteralValue = rightVal2
+            when (val cv = rightConst.number) {
+                -1.0 -> {
+                    // -left
+                    return PrefixExpression("-", leftValue, expr.position)
+                }
+                0.0 -> {
+                    // 0
+                    return NumericLiteralValue(rightConst.type, 0.0, expr.position)
+                }
+                1.0 -> {
+                    // left
+                    return expr2.left
+                }
+                in powersOfTwo -> {
+                    if (leftValue.inferType(program).isInteger) {
+                        // times a power of two => shift left
+                        val numshifts = log2(cv).toInt()
+                        return BinaryExpression(expr2.left, "<<", NumericLiteralValue.optimalInteger(numshifts, expr.position), expr.position)
+                    }
+                }
+                in negativePowersOfTwo -> {
+                    if (leftValue.inferType(program).isInteger) {
+                        // times a negative power of two => negate, then shift left
+                        val numshifts = log2(-cv).toInt()
+                        return BinaryExpression(PrefixExpression("-", expr2.left, expr.position), "<<", NumericLiteralValue.optimalInteger(numshifts, expr.position), expr.position)
+                    }
+                }
+            }
+        }
+        // no need to check for left val constant (because of associativity)
+
+        return null
+    }
+
+    private fun optimizeShiftLeft(expr: BinaryExpression, amountLv: NumericLiteralValue?): Expression? {
+        if (amountLv == null)
+            return null
+
+        val amount = amountLv.number.toInt()
+        if (amount == 0) {
+            return expr.left
+        }
+        val targetIDt = expr.left.inferType(program)
+        if(!targetIDt.isKnown)
+            throw FatalAstException("unknown dt")
+        when (val targetDt = targetIDt.getOr(DataType.UNDEFINED)) {
+            DataType.UBYTE, DataType.BYTE -> {
+                if (amount >= 8) {
+                    return NumericLiteralValue(targetDt, 0.0, expr.position)
+                }
+            }
+            DataType.UWORD, DataType.WORD -> {
+                if (amount >= 16) {
+                    return NumericLiteralValue(targetDt, 0.0, expr.position)
+                } else if (amount >= 8) {
+                    val lsb = FunctionCallExpression(IdentifierReference(listOf("lsb"), expr.position), mutableListOf(expr.left), expr.position)
+                    if (amount == 8) {
+                        return FunctionCallExpression(IdentifierReference(listOf("mkword"), expr.position), mutableListOf(lsb, NumericLiteralValue.optimalInteger(0, expr.position)), expr.position)
+                    }
+                    val shifted = BinaryExpression(lsb, "<<", NumericLiteralValue.optimalInteger(amount - 8, expr.position), expr.position)
+                    return FunctionCallExpression(IdentifierReference(listOf("mkword"), expr.position), mutableListOf(shifted, NumericLiteralValue.optimalInteger(0, expr.position)), expr.position)
+                }
+            }
+            else -> {
+            }
+        }
+        return null
+    }
+
+    private fun optimizeShiftRight(expr: BinaryExpression, amountLv: NumericLiteralValue?): Expression? {
+        if (amountLv == null)
+            return null
+
+        val amount = amountLv.number.toInt()
+        if (amount == 0) {
+            return expr.left
+        }
+        val idt = expr.left.inferType(program)
+        if(!idt.isKnown)
+            throw FatalAstException("unknown dt")
+        when (idt.getOr(DataType.UNDEFINED)) {
+            DataType.UBYTE -> {
+                if (amount >= 8) {
+                    return NumericLiteralValue.optimalInteger(0, expr.position)
+                }
+            }
+            DataType.BYTE -> {
+                if (amount > 8) {
+                    expr.right = NumericLiteralValue.optimalInteger(8, expr.right.position)
+                    return null
+                }
+            }
+            DataType.UWORD -> {
+                if (amount >= 16) {
+                    return NumericLiteralValue.optimalInteger(0, expr.position)
+                }
+                else if (amount >= 8) {
+                    val msb = FunctionCallExpression(IdentifierReference(listOf("msb"), expr.position), mutableListOf(expr.left), expr.position)
+                    if (amount == 8) {
+                        // mkword(0, msb(v))
+                        val zero = NumericLiteralValue(DataType.UBYTE, 0.0, expr.position)
+                        return FunctionCallExpression(IdentifierReference(listOf("mkword"), expr.position), mutableListOf(zero, msb), expr.position)
+                    }
+                    return TypecastExpression(BinaryExpression(msb, ">>", NumericLiteralValue.optimalInteger(amount - 8, expr.position), expr.position), DataType.UWORD, true, expr.position)
+                }
+            }
+            DataType.WORD -> {
+                if (amount > 16) {
+                    expr.right = NumericLiteralValue.optimalInteger(16, expr.right.position)
+                    return null
+                }
+            }
+            else -> {
+            }
+        }
+        return null
+    }
+
+    private fun reorderAssociativeWithConstant(expr: BinaryExpression, leftVal: NumericLiteralValue?): BinExprWithConstants {
+        if (expr.operator in AssociativeOperators && leftVal != null) {
+            // swap left and right so that right is always the constant
+            val tmp = expr.left
+            expr.left = expr.right
+            expr.right = tmp
+            return BinExprWithConstants(expr, expr.right.constValue(program), leftVal)
+        }
+        return BinExprWithConstants(expr, leftVal, expr.right.constValue(program))
+    }
+
+    private data class BinExprWithConstants(val expr: BinaryExpression, val leftVal: NumericLiteralValue?, val rightVal: NumericLiteralValue?)
+
+}

codeOptimizers/src/prog8/optimizer/Extensions.kt

@@ -0,0 +1,82 @@
+package prog8.optimizer
+
+import prog8.ast.IBuiltinFunctions
+import prog8.ast.Program
+import prog8.ast.base.DataType
+import prog8.ast.base.FatalAstException
+import prog8.ast.expressions.InferredTypes
+import prog8.compilerinterface.CompilationOptions
+import prog8.compilerinterface.ICompilationTarget
+import prog8.compilerinterface.IErrorReporter
+
+
+fun Program.constantFold(errors: IErrorReporter, compTarget: ICompilationTarget) {
+    val valuetypefixer = VarConstantValueTypeAdjuster(this, errors)
+    valuetypefixer.visit(this)
+    if(errors.noErrors()) {
+        valuetypefixer.applyModifications()
+
+        val replacer = ConstantIdentifierReplacer(this, errors, compTarget)
+        replacer.visit(this)
+        if (errors.noErrors()) {
+            replacer.applyModifications()
+
+            valuetypefixer.visit(this)
+            if(errors.noErrors()) {
+                valuetypefixer.applyModifications()
+
+                val optimizer = ConstantFoldingOptimizer(this)
+                optimizer.visit(this)
+                while (errors.noErrors() && optimizer.applyModifications() > 0) {
+                    optimizer.visit(this)
+                }
+
+                if (errors.noErrors()) {
+                    replacer.visit(this)
+                    replacer.applyModifications()
+                }
+            }
+        }
+    }
+
+    if(errors.noErrors())
+        modules.forEach { it.linkParents(namespace) }   // re-link in final configuration
+}
+
+
+fun Program.optimizeStatements(errors: IErrorReporter,
+                               functions: IBuiltinFunctions,
+                               compTarget: ICompilationTarget
+): Int {
+    val optimizer = StatementOptimizer(this, errors, functions, compTarget)
+    optimizer.visit(this)
+    val optimizationCount = optimizer.applyModifications()
+
+    modules.forEach { it.linkParents(this.namespace) }   // re-link in final configuration
+
+    return optimizationCount
+}
+
+fun Program.simplifyExpressions(errors: IErrorReporter) : Int {
+    val opti = ExpressionSimplifier(this, errors)
+    opti.visit(this)
+    return opti.applyModifications()
+}
+
+fun Program.splitBinaryExpressions(options: CompilationOptions, compTarget: ICompilationTarget) : Int {
+    val opti = BinExprSplitter(this, options, compTarget)
+    opti.visit(this)
+    return opti.applyModifications()
+}
+
+fun getTempVarName(dt: InferredTypes.InferredType): List<String> {
+    return when {
+        // TODO assume (hope) cx16.r9 isn't used for anything else during the use of this temporary variable...
+        dt istype DataType.UBYTE -> listOf("cx16", "r9L")
+        dt istype DataType.BYTE -> listOf("cx16", "r9sL")
+        dt istype DataType.UWORD -> listOf("cx16", "r9")
+        dt istype DataType.WORD -> listOf("cx16", "r9s")
+        dt.isPassByReference -> listOf("cx16", "r9")
+        else -> throw FatalAstException("invalid dt $dt")
+    }
+}

codeOptimizers/src/prog8/optimizer/StatementOptimizer.kt

@@ -0,0 +1,470 @@
+package prog8.optimizer
+
+import prog8.ast.*
+import prog8.ast.base.*
+import prog8.ast.expressions.*
+import prog8.ast.statements.*
+import prog8.ast.walk.AstWalker
+import prog8.ast.walk.IAstModification
+import prog8.compilerinterface.ICompilationTarget
+import prog8.compilerinterface.IErrorReporter
+import kotlin.math.floor
+
+
+class StatementOptimizer(private val program: Program,
+                                  private val errors: IErrorReporter,
+                                  private val functions: IBuiltinFunctions,
+                                  private val compTarget: ICompilationTarget
+) : AstWalker() {
+
+    override fun before(functionCallExpr: FunctionCallExpression, parent: Node): Iterable<IAstModification> {
+        // if the first instruction in the called subroutine is a return statement with a simple value,
+        // remove the jump altogeter and inline the returnvalue directly.
+
+        fun scopePrefix(variable: IdentifierReference): IdentifierReference {
+            val target = variable.targetStatement(program) as INamedStatement
+            return IdentifierReference(target.scopedName, variable.position)
+        }
+
+        val subroutine = functionCallExpr.target.targetSubroutine(program)
+        if(subroutine!=null) {
+            val first = subroutine.statements.asSequence().filterNot { it is VarDecl || it is Directive }.firstOrNull()
+            if(first is Return && first.value?.isSimple==true) {
+                val copy = when(val orig = first.value!!) {
+                    is AddressOf -> {
+                        val scoped = scopePrefix(orig.identifier)
+                        AddressOf(scoped, orig.position)
+                    }
+                    is DirectMemoryRead -> {
+                        when(val expr = orig.addressExpression) {
+                            is NumericLiteralValue -> DirectMemoryRead(expr.copy(), orig.position)
+                            else -> return noModifications
+                        }
+                    }
+                    is IdentifierReference -> scopePrefix(orig)
+                    is NumericLiteralValue -> orig.copy()
+                    is StringLiteralValue -> orig.copy()
+                    else -> return noModifications
+                }
+                return listOf(IAstModification.ReplaceNode(functionCallExpr, copy, parent))
+            }
+        }
+        return noModifications
+    }
+
+
+
+    override fun after(functionCallStatement: FunctionCallStatement, parent: Node): Iterable<IAstModification> {
+        if(functionCallStatement.target.targetStatement(program) is BuiltinFunctionPlaceholder) {
+            val functionName = functionCallStatement.target.nameInSource[0]
+            if (functionName in functions.purefunctionNames) {
+                errors.warn("statement has no effect (function return value is discarded)", functionCallStatement.position)
+                return listOf(IAstModification.Remove(functionCallStatement, parent as IStatementContainer))
+            }
+        }
+
+        // printing a literal string of just 2 or 1 characters is replaced by directly outputting those characters
+        // only do this optimization if the arg is a known-constant string literal instead of a user defined variable.
+        if(functionCallStatement.target.nameInSource==listOf("txt", "print")) {
+            val arg = functionCallStatement.args.single()
+            val stringVar: IdentifierReference? = if(arg is AddressOf) {
+                arg.identifier
+            } else {
+                arg as? IdentifierReference
+            }
+            if(stringVar!=null && stringVar.wasStringLiteral(program)) {
+                val string = stringVar.targetVarDecl(program)?.value as? StringLiteralValue
+                if(string!=null) {
+                    val pos = functionCallStatement.position
+                    if (string.value.length == 1) {
+                        val firstCharEncoded = compTarget.encodeString(string.value, string.encoding)[0]
+                        val chrout = FunctionCallStatement(
+                            IdentifierReference(listOf("txt", "chrout"), pos),
+                            mutableListOf(NumericLiteralValue(DataType.UBYTE, firstCharEncoded.toDouble(), pos)),
+                            functionCallStatement.void, pos
+                        )
+                        return listOf(IAstModification.ReplaceNode(functionCallStatement, chrout, parent))
+                    } else if (string.value.length == 2) {
+                        val firstTwoCharsEncoded = compTarget.encodeString(string.value.take(2), string.encoding)
+                        val chrout1 = FunctionCallStatement(
+                            IdentifierReference(listOf("txt", "chrout"), pos),
+                            mutableListOf(NumericLiteralValue(DataType.UBYTE, firstTwoCharsEncoded[0].toDouble(), pos)),
+                            functionCallStatement.void, pos
+                        )
+                        val chrout2 = FunctionCallStatement(
+                            IdentifierReference(listOf("txt", "chrout"), pos),
+                            mutableListOf(NumericLiteralValue(DataType.UBYTE, firstTwoCharsEncoded[1].toDouble(), pos)),
+                            functionCallStatement.void, pos
+                        )
+                        return listOf(
+                            IAstModification.InsertBefore(functionCallStatement, chrout1, parent as IStatementContainer),
+                            IAstModification.ReplaceNode(functionCallStatement, chrout2, parent)
+                        )
+                    }
+                }
+            }
+        }
+
+        // if the first instruction in the called subroutine is a return statement, remove the jump altogeter
+        val subroutine = functionCallStatement.target.targetSubroutine(program)
+        if(subroutine!=null) {
+            val first = subroutine.statements.asSequence().filterNot { it is VarDecl || it is Directive }.firstOrNull()
+            if(first is Return)
+                return listOf(IAstModification.Remove(functionCallStatement, parent as IStatementContainer))
+        }
+
+        // see if we can optimize any complex arguments
+        // TODO for now, only works for single-argument functions because we use just 1 temp var: R9
+        if(functionCallStatement.target.nameInSource !in listOf(listOf("pop"), listOf("popw")) && functionCallStatement.args.size==1) {
+            val arg = functionCallStatement.args[0]
+            if(!arg.isSimple && arg !is TypecastExpression && arg !is IFunctionCall) {
+                val name = getTempVarName(arg.inferType(program))
+                val tempvar = IdentifierReference(name, functionCallStatement.position)
+                val assignTempvar = Assignment(AssignTarget(tempvar.copy(), null, null, functionCallStatement.position), arg, AssignmentOrigin.OPTIMIZER, functionCallStatement.position)
+                return listOf(
+                    IAstModification.InsertBefore(functionCallStatement, assignTempvar, parent as IStatementContainer),
+                    IAstModification.ReplaceNode(arg, tempvar, functionCallStatement)
+                )
+            }
+        }
+
+
+        return noModifications
+    }
+
+    override fun after(ifElse: IfElse, parent: Node): Iterable<IAstModification> {
+        // remove empty if statements
+        if(ifElse.truepart.isEmpty() && ifElse.elsepart.isEmpty())
+            return listOf(IAstModification.Remove(ifElse, parent as IStatementContainer))
+
+        // empty true part? switch with the else part
+        if(ifElse.truepart.isEmpty() && ifElse.elsepart.isNotEmpty()) {
+            val invertedCondition = PrefixExpression("not", ifElse.condition, ifElse.condition.position)
+            val emptyscope = AnonymousScope(mutableListOf(), ifElse.elsepart.position)
+            val truepart = AnonymousScope(ifElse.elsepart.statements, ifElse.truepart.position)
+            return listOf(
+                    IAstModification.ReplaceNode(ifElse.condition, invertedCondition, ifElse),
+                    IAstModification.ReplaceNode(ifElse.truepart, truepart, ifElse),
+                    IAstModification.ReplaceNode(ifElse.elsepart, emptyscope, ifElse)
+            )
+        }
+
+        val constvalue = ifElse.condition.constValue(program)
+        if(constvalue!=null) {
+            return if(constvalue.asBooleanValue){
+                // always true -> keep only if-part
+                errors.warn("condition is always true", ifElse.condition.position)
+                listOf(IAstModification.ReplaceNode(ifElse, ifElse.truepart, parent))
+            } else {
+                // always false -> keep only else-part
+                errors.warn("condition is always false", ifElse.condition.position)
+                listOf(IAstModification.ReplaceNode(ifElse, ifElse.elsepart, parent))
+            }
+        }
+
+        return noModifications
+    }
+
+    override fun after(forLoop: ForLoop, parent: Node): Iterable<IAstModification> {
+        if(forLoop.body.isEmpty()) {
+            errors.warn("removing empty for loop", forLoop.position)
+            return listOf(IAstModification.Remove(forLoop, parent as IStatementContainer))
+        } else if(forLoop.body.statements.size==1) {
+            val loopvar = forLoop.body.statements[0] as? VarDecl
+            if(loopvar!=null && loopvar.name==forLoop.loopVar.nameInSource.singleOrNull()) {
+                // remove empty for loop (only loopvar decl in it)
+                return listOf(IAstModification.Remove(forLoop, parent as IStatementContainer))
+            }
+        }
+
+        val range = forLoop.iterable as? RangeExpression
+        if(range!=null) {
+            if (range.size() == 1) {
+                // for loop over a (constant) range of just a single value-- optimize the loop away
+                // loopvar/reg = range value , follow by block
+                val scope = AnonymousScope(mutableListOf(), forLoop.position)
+                scope.statements.add(Assignment(AssignTarget(forLoop.loopVar, null, null, forLoop.position), range.from, AssignmentOrigin.OPTIMIZER, forLoop.position))
+                scope.statements.addAll(forLoop.body.statements)
+                return listOf(IAstModification.ReplaceNode(forLoop, scope, parent))
+            }
+        }
+        val iterable = (forLoop.iterable as? IdentifierReference)?.targetVarDecl(program)
+        if(iterable!=null) {
+            if(iterable.datatype==DataType.STR) {
+                val sv = iterable.value as StringLiteralValue
+                val size = sv.value.length
+                if(size==1) {
+                    // loop over string of length 1 -> just assign the single character
+                    val character = compTarget.encodeString(sv.value, sv.encoding)[0]
+                    val byte = NumericLiteralValue(DataType.UBYTE, character.toDouble(), iterable.position)
+                    val scope = AnonymousScope(mutableListOf(), forLoop.position)
+                    scope.statements.add(Assignment(AssignTarget(forLoop.loopVar, null, null, forLoop.position), byte, AssignmentOrigin.OPTIMIZER, forLoop.position))
+                    scope.statements.addAll(forLoop.body.statements)
+                    return listOf(IAstModification.ReplaceNode(forLoop, scope, parent))
+                }
+            }
+            else if(iterable.datatype in ArrayDatatypes) {
+                val size = iterable.arraysize!!.constIndex()
+                if(size==1) {
+                    // loop over array of length 1 -> just assign the single value
+                    val av = (iterable.value as ArrayLiteralValue).value[0].constValue(program)?.number
+                    if(av!=null) {
+                        val scope = AnonymousScope(mutableListOf(), forLoop.position)
+                        scope.statements.add(Assignment(
+                                AssignTarget(forLoop.loopVar, null, null, forLoop.position), NumericLiteralValue.optimalInteger(av.toInt(), iterable.position),
+                                AssignmentOrigin.OPTIMIZER, forLoop.position))
+                        scope.statements.addAll(forLoop.body.statements)
+                        return listOf(IAstModification.ReplaceNode(forLoop, scope, parent))
+                    }
+                }
+            }
+        }
+
+        return noModifications
+    }
+
+    override fun before(untilLoop: UntilLoop, parent: Node): Iterable<IAstModification> {
+        val constvalue = untilLoop.condition.constValue(program)
+        if(constvalue!=null) {
+            return if(constvalue.asBooleanValue) {
+                // always true -> keep only the statement block
+                errors.warn("condition is always true", untilLoop.condition.position)
+                listOf(IAstModification.ReplaceNode(untilLoop, untilLoop.body, parent))
+            } else {
+                // always false
+                val forever = RepeatLoop(null, untilLoop.body, untilLoop.position)
+                listOf(IAstModification.ReplaceNode(untilLoop, forever, parent))
+            }
+        }
+        return noModifications
+    }
+
+    override fun before(whileLoop: WhileLoop, parent: Node): Iterable<IAstModification> {
+        val constvalue = whileLoop.condition.constValue(program)
+        if(constvalue!=null) {
+            return if(constvalue.asBooleanValue) {
+                // always true
+                val forever = RepeatLoop(null, whileLoop.body, whileLoop.position)
+                listOf(IAstModification.ReplaceNode(whileLoop, forever, parent))
+            } else {
+                // always false -> remove the while statement altogether
+                errors.warn("condition is always false", whileLoop.condition.position)
+                listOf(IAstModification.Remove(whileLoop, parent as IStatementContainer))
+            }
+        }
+        return noModifications
+    }
+
+    override fun after(repeatLoop: RepeatLoop, parent: Node): Iterable<IAstModification> {
+        val iter = repeatLoop.iterations
+        if(iter!=null) {
+            if(repeatLoop.body.isEmpty()) {
+                errors.warn("empty loop removed", repeatLoop.position)
+                return listOf(IAstModification.Remove(repeatLoop, parent as IStatementContainer))
+            }
+            val iterations = iter.constValue(program)?.number?.toInt()
+            if (iterations == 0) {
+                errors.warn("iterations is always 0, removed loop", iter.position)
+                return listOf(IAstModification.Remove(repeatLoop, parent as IStatementContainer))
+            }
+            if (iterations == 1) {
+                errors.warn("iterations is always 1", iter.position)
+                return listOf(IAstModification.ReplaceNode(repeatLoop, repeatLoop.body, parent))
+            }
+        }
+        return noModifications
+    }
+
+
+    // NOTE: do NOT remove a jump to the next statement, because this will lead to wrong code when this occurs at the end of a subroutine
+    // if we want to optimize this away, it can be done later at code generation time.
+
+    override fun after(gosub: GoSub, parent: Node): Iterable<IAstModification> {
+        // if the next statement is return with no returnvalue, change into a regular jump if there are no parameters as well.
+        val subroutineParams = gosub.identifier?.targetSubroutine(program)?.parameters
+        if(subroutineParams!=null && subroutineParams.isEmpty()) {
+            val returnstmt = gosub.nextSibling() as? Return
+            if(returnstmt!=null && returnstmt.value==null) {
+                return listOf(
+                    IAstModification.Remove(returnstmt, parent as IStatementContainer),
+                    IAstModification.ReplaceNode(gosub, Jump(gosub.address, gosub.identifier, gosub.generatedLabel, gosub.position), parent)
+                )
+            }
+        }
+        return noModifications
+    }
+
+    override fun before(assignment: Assignment, parent: Node): Iterable<IAstModification> {
+
+        val binExpr = assignment.value as? BinaryExpression
+        if(binExpr!=null) {
+            if(binExpr.left isSameAs assignment.target) {
+                val rExpr = binExpr.right as? BinaryExpression
+                if(rExpr!=null) {
+                    val op1 = binExpr.operator
+                    val op2 = rExpr.operator
+
+                    if(rExpr.left is NumericLiteralValue && op2 in AssociativeOperators) {
+                        // associative operator, make sure the constant numeric value is second (right)
+                        return listOf(IAstModification.SwapOperands(rExpr))
+                    }
+
+                    val rNum = (rExpr.right as? NumericLiteralValue)?.number
+                    if(rNum!=null) {
+                        if (op1 == "+" || op1 == "-") {
+                            if (op2 == "+") {
+                                // A = A +/- B + N  --->  A = A +/- B  ;  A = A + N
+                                val expr2 = BinaryExpression(binExpr.left, binExpr.operator, rExpr.left, binExpr.position)
+                                val addConstant = Assignment(
+                                        assignment.target.copy(),
+                                        BinaryExpression(binExpr.left.copy(), "+", rExpr.right, rExpr.position),
+                                        AssignmentOrigin.OPTIMIZER, assignment.position
+                                )
+                                return listOf(
+                                        IAstModification.ReplaceNode(binExpr, expr2, binExpr.parent),
+                                        IAstModification.InsertAfter(assignment, addConstant, parent as IStatementContainer))
+                            } else if (op2 == "-") {
+                                // A = A +/- B - N  --->  A = A +/- B  ;  A = A - N
+                                val expr2 = BinaryExpression(binExpr.left, binExpr.operator, rExpr.left, binExpr.position)
+                                val subConstant = Assignment(
+                                        assignment.target.copy(),
+                                        BinaryExpression(binExpr.left.copy(), "-", rExpr.right, rExpr.position),
+                                        AssignmentOrigin.OPTIMIZER, assignment.position
+                                )
+                                return listOf(
+                                        IAstModification.ReplaceNode(binExpr, expr2, binExpr.parent),
+                                        IAstModification.InsertAfter(assignment, subConstant, parent as IStatementContainer))
+                            }
+                        }
+                    }
+                }
+            }
+
+            if(binExpr.operator in AssociativeOperators && binExpr.right isSameAs assignment.target) {
+                // associative operator, swap the operands so that the assignment target is first (left)
+                // unless the other operand is the same in which case we don't swap (endless loop!)
+                if (!(binExpr.left isSameAs binExpr.right))
+                    return listOf(IAstModification.SwapOperands(binExpr))
+            }
+
+        }
+
+        return noModifications
+    }
+
+    override fun after(assignment: Assignment, parent: Node): Iterable<IAstModification> {
+        if(assignment.target isSameAs assignment.value) {
+            // remove assignment to self
+            return listOf(IAstModification.Remove(assignment, parent as IStatementContainer))
+        }
+
+        val targetIDt = assignment.target.inferType(program)
+        if(!targetIDt.isKnown)
+            return noModifications
+
+        // optimize binary expressions a bit
+        val bexpr=assignment.value as? BinaryExpression
+        if(bexpr!=null) {
+            val rightCv = bexpr.right.constValue(program)?.number
+            if(bexpr.operator=="-" && rightCv==null) {
+                if(bexpr.right isSameAs assignment.target) {
+                    // X = value - X  -->  X = -X ; X += value  (to avoid need of stack-evaluation)
+                    val negation = PrefixExpression("-", bexpr.right.copy(), bexpr.position)
+                    val addValue = Assignment(assignment.target.copy(), BinaryExpression(bexpr.right, "+", bexpr.left, bexpr.position), AssignmentOrigin.OPTIMIZER, assignment.position)
+                    return listOf(
+                        IAstModification.ReplaceNode(bexpr, negation, assignment),
+                        IAstModification.InsertAfter(assignment, addValue, parent as IStatementContainer)
+                    )
+                }
+            }
+
+            if (rightCv != null && assignment.target isSameAs bexpr.left) {
+                // assignments of the form:  X = X <operator> <expr>
+                // remove assignments that have no effect (such as X=X+0)
+                // optimize/rewrite some other expressions
+                val targetDt = targetIDt.getOr(DataType.UNDEFINED)
+                val vardeclDt = (assignment.target.identifier?.targetVarDecl(program))?.type
+                when (bexpr.operator) {
+                    "+" -> {
+                        if (rightCv == 0.0) {
+                            return listOf(IAstModification.Remove(assignment, parent as IStatementContainer))
+                        } else if (targetDt in IntegerDatatypes && floor(rightCv) == rightCv) {
+                            if (vardeclDt != VarDeclType.MEMORY && rightCv in 1.0..4.0) {
+                                // replace by several INCs if it's not a memory address (inc on a memory mapped register doesn't work very well)
+                                val incs = AnonymousScope(mutableListOf(), assignment.position)
+                                repeat(rightCv.toInt()) {
+                                    incs.statements.add(PostIncrDecr(assignment.target.copy(), "++", assignment.position))
+                                }
+                                listOf(IAstModification.ReplaceNode(assignment, if(incs.statements.size==1) incs.statements[0] else incs, parent))
+                            }
+                        }
+                    }
+                    "-" -> {
+                        if (rightCv == 0.0) {
+                            return listOf(IAstModification.Remove(assignment, parent as IStatementContainer))
+                        } else if (targetDt in IntegerDatatypes && floor(rightCv) == rightCv) {
+                            if (vardeclDt != VarDeclType.MEMORY && rightCv in 1.0..4.0) {
+                                // replace by several DECs if it's not a memory address (dec on a memory mapped register doesn't work very well)
+                                val decs = AnonymousScope(mutableListOf(), assignment.position)
+                                repeat(rightCv.toInt()) {
+                                    decs.statements.add(PostIncrDecr(assignment.target.copy(), "--", assignment.position))
+                                }
+                                return listOf(IAstModification.ReplaceNode(assignment, decs, parent))
+                            }
+                        }
+                    }
+                    "*" -> if (rightCv == 1.0) return listOf(IAstModification.Remove(assignment, parent as IStatementContainer))
+                    "/" -> if (rightCv == 1.0) return listOf(IAstModification.Remove(assignment, parent as IStatementContainer))
+                    "**" -> if (rightCv == 1.0) return listOf(IAstModification.Remove(assignment, parent as IStatementContainer))
+                    "|" -> if (rightCv == 0.0) return listOf(IAstModification.Remove(assignment, parent as IStatementContainer))
+                    "^" -> if (rightCv == 0.0) return listOf(IAstModification.Remove(assignment, parent as IStatementContainer))
+                    "<<" -> {
+                        if (rightCv == 0.0)
+                            return listOf(IAstModification.Remove(assignment, parent as IStatementContainer))
+                    }
+                    ">>" -> {
+                        if (rightCv == 0.0)
+                            return listOf(IAstModification.Remove(assignment, parent as IStatementContainer))
+                    }
+                }
+
+            }
+        }
+
+        return noModifications
+    }
+
+    override fun after(returnStmt: Return, parent: Node): Iterable<IAstModification> {
+        fun returnViaIntermediaryVar(value: Expression): Iterable<IAstModification>? {
+            val subr = returnStmt.definingSubroutine!!
+            val returnDt = subr.returntypes.single()
+            if (returnDt in IntegerDatatypes) {
+                // first assign to intermediary variable, then return that
+                val returnVarName = "retval_interm_" + when(returnDt) {
+                    DataType.UBYTE -> "ub"
+                    DataType.BYTE -> "b"
+                    DataType.UWORD -> "uw"
+                    DataType.WORD -> "w"
+                    else -> "<undefined>"
+                }
+                val returnValueIntermediary = IdentifierReference(listOf("prog8_lib", returnVarName), returnStmt.position)
+                val tgt = AssignTarget(returnValueIntermediary, null, null, returnStmt.position)
+                val assign = Assignment(tgt, value, AssignmentOrigin.OPTIMIZER, returnStmt.position)
+                val returnReplacement = Return(returnValueIntermediary.copy(), returnStmt.position)
+                return listOf(
+                    IAstModification.InsertBefore(returnStmt, assign, parent as IStatementContainer),
+                    IAstModification.ReplaceNode(returnStmt, returnReplacement, parent)
+                )
+            }
+            return null
+        }
+
+        if(returnStmt.value is BinaryExpression) {
+            val mod = returnViaIntermediaryVar(returnStmt.value!!)
+            if(mod!=null)
+                return mod
+        }
+
+        return noModifications
+    }
+}

codeOptimizers/src/prog8/optimizer/UnusedCodeRemover.kt

@@ -0,0 +1,248 @@
+package prog8.optimizer
+
+import prog8.ast.*
+import prog8.ast.base.DataType
+import prog8.ast.base.VarDeclType
+import prog8.ast.expressions.*
+import prog8.ast.statements.*
+import prog8.ast.walk.AstWalker
+import prog8.ast.walk.IAstModification
+import prog8.compilerinterface.CallGraph
+import prog8.compilerinterface.ICompilationTarget
+import prog8.compilerinterface.IErrorReporter
+import prog8.compilerinterface.isIOAddress
+
+
+class UnusedCodeRemover(private val program: Program,
+                        private val errors: IErrorReporter,
+                        private val compTarget: ICompilationTarget
+): AstWalker() {
+
+    private val callgraph = CallGraph(program)
+
+    override fun before(module: Module, parent: Node): Iterable<IAstModification> {
+        return if (!module.isLibrary && (module.containsNoCodeNorVars || callgraph.unused(module)))
+            listOf(IAstModification.Remove(module, parent as IStatementContainer))
+        else
+            noModifications
+    }
+
+    override fun before(breakStmt: Break, parent: Node): Iterable<IAstModification> {
+        reportUnreachable(breakStmt)
+        return emptyList()
+    }
+
+    override fun before(jump: Jump, parent: Node): Iterable<IAstModification> {
+        reportUnreachable(jump)
+        return emptyList()
+    }
+
+    override fun before(returnStmt: Return, parent: Node): Iterable<IAstModification> {
+        reportUnreachable(returnStmt)
+        return emptyList()
+    }
+
+    override fun before(functionCallStatement: FunctionCallStatement, parent: Node): Iterable<IAstModification> {
+        if(functionCallStatement.target.nameInSource.last() == "exit")
+            reportUnreachable(functionCallStatement)
+        return emptyList()
+    }
+
+    private fun reportUnreachable(stmt: Statement) {
+        when(val next = stmt.nextSibling()) {
+            null, is Label, is Directive, is VarDecl, is InlineAssembly, is Subroutine -> {}
+            else -> errors.warn("unreachable code", next.position)
+        }
+    }
+
+    override fun after(scope: AnonymousScope, parent: Node): Iterable<IAstModification> {
+        return deduplicateAssignments(scope.statements, scope)
+    }
+
+    override fun after(block: Block, parent: Node): Iterable<IAstModification> {
+        if("force_output" !in block.options()) {
+            if (block.containsNoCodeNorVars) {
+                if(block.name != internedStringsModuleName)
+                    errors.warn("removing unused block '${block.name}'", block.position)
+                return listOf(IAstModification.Remove(block, parent as IStatementContainer))
+            }
+            if(callgraph.unused(block)) {
+                if(block.statements.any{ it !is VarDecl || it.type==VarDeclType.VAR})
+                    errors.warn("removing unused block '${block.name}'", block.position)
+                return listOf(IAstModification.Remove(block, parent as IStatementContainer))
+            }
+        }
+
+        return deduplicateAssignments(block.statements, block)
+    }
+
+    override fun after(subroutine: Subroutine, parent: Node): Iterable<IAstModification> {
+        val forceOutput = "force_output" in subroutine.definingBlock.options()
+        if (subroutine !== program.entrypoint && !forceOutput && !subroutine.inline && !subroutine.isAsmSubroutine) {
+            if(callgraph.unused(subroutine)) {
+                if(subroutine.containsNoCodeNorVars) {
+                    if(!subroutine.definingModule.isLibrary)
+                        errors.warn("removing empty subroutine '${subroutine.name}'", subroutine.position)
+                    val removals = mutableListOf(IAstModification.Remove(subroutine, parent as IStatementContainer))
+                    callgraph.calledBy[subroutine]?.let {
+                        for(node in it)
+                            removals.add(IAstModification.Remove(node, node.parent as IStatementContainer))
+                    }
+                    return removals
+                }
+                if(!subroutine.definingModule.isLibrary)
+                    errors.warn("removing unused subroutine '${subroutine.name}'", subroutine.position)
+                return listOf(IAstModification.Remove(subroutine, parent as IStatementContainer))
+            }
+        }
+
+        return deduplicateAssignments(subroutine.statements, subroutine)
+    }
+
+    override fun after(decl: VarDecl, parent: Node): Iterable<IAstModification> {
+        if(decl.type==VarDeclType.VAR) {
+            val forceOutput = "force_output" in decl.definingBlock.options()
+            if (!forceOutput && decl.origin==VarDeclOrigin.USERCODE && !decl.sharedWithAsm && !decl.definingBlock.isInLibrary) {
+                val usages = callgraph.usages(decl)
+                if (usages.isEmpty()) {
+                    errors.warn("removing unused variable '${decl.name}'", decl.position)
+                    return listOf(IAstModification.Remove(decl, parent as IStatementContainer))
+                }
+                else {
+                    if(usages.size==1) {
+                        val singleUse = usages[0].parent
+                        if(singleUse is AssignTarget) {
+                            val assignment = singleUse.parent as Assignment
+                            if(assignment.value !is IFunctionCall) {
+                                errors.warn("removing unused variable '${decl.name}'", decl.position)
+                                return listOf(
+                                    IAstModification.Remove(decl, parent as IStatementContainer),
+                                    IAstModification.Remove(assignment, assignment.parent as IStatementContainer)
+                                )
+                            }
+                        }
+                    }
+                }
+            }
+        }
+
+        return noModifications
+    }
+
+    private fun deduplicateAssignments(statements: List<Statement>, scope: IStatementContainer): List<IAstModification> {
+        // removes 'duplicate' assignments that assign the same target directly after another, unless it is a function call
+        val linesToRemove = mutableListOf<Assignment>()
+        val modifications = mutableListOf<IAstModification>()
+
+        fun substituteZeroInBinexpr(expr: BinaryExpression, zero: NumericLiteralValue, assign1: Assignment, assign2: Assignment) {
+            if(expr.left isSameAs assign2.target) {
+                // X = X <oper> Right
+                linesToRemove.add(assign1)
+                modifications.add(IAstModification.ReplaceNode(
+                    expr.left, zero, expr
+                ))
+            }
+            if(expr.right isSameAs assign2.target) {
+                // X = Left <oper> X
+                linesToRemove.add(assign1)
+                modifications.add(IAstModification.ReplaceNode(
+                    expr.right, zero, expr
+                ))
+            }
+            val leftBinExpr = expr.left as? BinaryExpression
+            val rightBinExpr = expr.right as? BinaryExpression
+            if(leftBinExpr!=null && rightBinExpr==null) {
+                if(leftBinExpr.left isSameAs assign2.target) {
+                    // X = (X <oper> Right) <oper> Something
+                    linesToRemove.add(assign1)
+                    modifications.add(IAstModification.ReplaceNode(
+                        leftBinExpr.left, zero, leftBinExpr
+                    ))
+                }
+                if(leftBinExpr.right isSameAs assign2.target) {
+                    // X = (Left <oper> X) <oper> Something
+                    linesToRemove.add(assign1)
+                    modifications.add(IAstModification.ReplaceNode(
+                        leftBinExpr.right, zero, leftBinExpr
+                    ))
+                }
+            }
+            if(leftBinExpr==null && rightBinExpr!=null) {
+                if(rightBinExpr.left isSameAs assign2.target) {
+                    // X = Something <oper> (X <oper> Right)
+                    linesToRemove.add(assign1)
+                    modifications.add(IAstModification.ReplaceNode(
+                        rightBinExpr.left, zero, rightBinExpr
+                    ))
+                }
+                if(rightBinExpr.right isSameAs assign2.target) {
+                    // X = Something <oper> (Left <oper> X)
+                    linesToRemove.add(assign1)
+                    modifications.add(IAstModification.ReplaceNode(
+                        rightBinExpr.right, zero, rightBinExpr
+                    ))
+                }
+            }
+        }
+
+        fun substituteZeroInPrefixexpr(expr: PrefixExpression, zero: NumericLiteralValue, assign1: Assignment, assign2: Assignment) {
+            if(expr.expression isSameAs assign2.target) {
+                linesToRemove.add(assign1)
+                modifications.add(IAstModification.ReplaceNode(
+                    expr.expression, zero, expr
+                ))
+            }
+        }
+
+        fun substituteZeroInTypecast(expr: TypecastExpression, zero: NumericLiteralValue, assign1: Assignment, assign2: Assignment) {
+            if(expr.expression isSameAs assign2.target) {
+                linesToRemove.add(assign1)
+                modifications.add(IAstModification.ReplaceNode(
+                    expr.expression, zero, expr
+                ))
+            }
+            val subCast = expr.expression as? TypecastExpression
+            if(subCast!=null && subCast.expression isSameAs assign2.target) {
+                linesToRemove.add(assign1)
+                modifications.add(IAstModification.ReplaceNode(
+                    subCast.expression, zero, subCast
+                ))
+            }
+        }
+
+        for (stmtPairs in statements.windowed(2, step = 1)) {
+            val assign1 = stmtPairs[0] as? Assignment
+            val assign2 = stmtPairs[1] as? Assignment
+            if (assign1 != null && assign2 != null) {
+                val cvalue1 = assign1.value.constValue(program)
+                if(cvalue1!=null && cvalue1.number==0.0 && assign2.target.isSameAs(assign1.target, program) && assign2.isAugmentable) {
+                    val value2 = assign2.value
+                    val zero = VarDecl.defaultZero(value2.inferType(program).getOr(DataType.UNDEFINED), value2.position)
+                    when(value2) {
+                        is BinaryExpression -> substituteZeroInBinexpr(value2, zero, assign1, assign2)
+                        is PrefixExpression -> substituteZeroInPrefixexpr(value2, zero, assign1, assign2)
+                        is TypecastExpression -> substituteZeroInTypecast(value2, zero, assign1, assign2)
+                        else -> {}
+                    }
+                } else {
+                    if (assign1.target.isSameAs(assign2.target, program) && !assign1.target.isIOAddress(compTarget.machine))  {
+                        if(assign2.target.identifier==null || !assign2.value.referencesIdentifier(assign2.target.identifier!!.nameInSource))
+                            // only remove the second assignment if its value is a simple expression!
+                            when(assign2.value) {
+                                is PrefixExpression,
+                                is BinaryExpression,
+                                is TypecastExpression,
+                                is FunctionCallExpression -> { /* don't remove */ }
+                                else -> {
+                                    if(assign1.value !is IFunctionCall)
+                                        linesToRemove.add(assign1)
+                                }
+                            }
+                    }
+                }
+            }
+        }
+
+        return modifications + linesToRemove.map { IAstModification.Remove(it, scope) }
+    }
+}

compiler/build.gradle

@@ -1,55 +1,55 @@
-buildscript {
-    dependencies {
-        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlinVersion"
-    }
-}
-
 plugins {
-    // id "org.jetbrains.kotlin.jvm" version $kotlinVersion
-    id 'application'
-    id 'org.jetbrains.dokka' version "0.9.18"
-    id 'com.github.johnrengelman.shadow' version '5.1.0'
     id 'java'
+    id 'application'
+    id "org.jetbrains.kotlin.jvm"
+    id 'com.github.johnrengelman.shadow' version '7.1.0'
+    id "io.kotest" version "0.3.8"
 }
 
-apply plugin: "kotlin"
+java {
-apply plugin: "java"
+    toolchain {
-
+        languageVersion = JavaLanguageVersion.of(javaVersion)
-
+    }
-repositories {
-    mavenLocal()
-    mavenCentral()
-    jcenter()
-}
-
-def prog8version = rootProject.file('compiler/res/version.txt').text.trim()
-
-dependencies {
-    implementation project(':parser')
-    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8:$kotlinVersion"
-    // implementation "org.jetbrains.kotlin:kotlin-reflect:$kotlinVersion"
-    // runtime "org.jetbrains.kotlin:kotlin-reflect:$kotlinVersion"
-    runtime 'org.antlr:antlr4-runtime:4.7.2'
-    runtime project(':parser')
-
-    testImplementation "org.jetbrains.kotlin:kotlin-test-junit5:$kotlinVersion"
-    testImplementation 'org.junit.jupiter:junit-jupiter-api:5.3.2'
-    testImplementation 'org.hamcrest:hamcrest-junit:2.0.0.0'
-
-    testRuntimeOnly 'org.junit.jupiter:junit-jupiter-engine:5.3.2'
 }
 
 compileKotlin {
     kotlinOptions {
-        jvmTarget = "1.8"
+        jvmTarget = javaVersion
-        verbose = true
-        // freeCompilerArgs += "-XXLanguage:+NewInference"
     }
 }
 
 compileTestKotlin {
     kotlinOptions {
-        jvmTarget = "1.8"
+        jvmTarget = javaVersion
+    }
+}
+
+def prog8version = rootProject.file('compiler/res/version.txt').text.trim()
+
+dependencies {
+    implementation project(':compilerInterfaces')
+    implementation project(':codeOptimizers')
+    implementation project(':compilerAst')
+    implementation project(':codeGeneration')
+    implementation 'org.antlr:antlr4-runtime:4.9.2'
+    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8"
+    // implementation "org.jetbrains.kotlin:kotlin-reflect"
+    implementation 'org.jetbrains.kotlinx:kotlinx-cli:0.3.3'
+    implementation "com.michael-bull.kotlin-result:kotlin-result-jvm:1.1.12"
+
+    testImplementation 'io.kotest:kotest-runner-junit5-jvm:4.6.3'
+}
+
+configurations.all {
+    exclude group: 'com.ibm.icu', module: 'icu4j'
+    exclude group: "org.antlr", module: "antlr4"
+}
+
+configurations {
+    // strange antlr plugin issue, see https://github.com/gradle/gradle/issues/820
+    // this avoids linking in the complete antlr binary jar
+    compile {
+        extendsFrom = extendsFrom.findAll { it != configurations.antlr }
     }
 }
 
@@ -64,7 +64,8 @@ sourceSets {
     }
     test {
         java {
-            srcDirs = ["${project.projectDir}/test"]
+            srcDir "${project.projectDir}/test"
+            srcDir "${project(':compilerAst').projectDir}/test/helpers"
         }
     }
 }
@@ -72,21 +73,13 @@ sourceSets {
 startScripts.enabled = true
 
 application {
-    mainClassName = 'prog8.CompilerMainKt'
+    mainClass = 'prog8.CompilerMainKt'
     applicationName = 'p8compile'
 }
 
-artifacts {
-    archives shadowJar
-}
-
-
-// To create a fat-jar use the 'create_compiler_jar' script for now
-// @todo investigate https://imperceptiblethoughts.com/shadow/introduction/
-
 shadowJar {
-    baseName = 'prog8compiler'
+    archiveBaseName = 'prog8compiler'
-    version = prog8version
+    archiveVersion = prog8version
     // minimize()
 }
 
@@ -100,12 +93,8 @@ test {
 
     // Show test results.
     testLogging {
-        events "passed", "skipped", "failed"
+        events "skipped", "failed"
     }
 }
 
-
+build.finalizedBy installDist, installShadowDist
-dokka {
-    outputFormat = 'html'
-    outputDirectory = "$buildDir/kdoc"
-}

compiler/compiler.iml

@@ -8,11 +8,17 @@
       <sourceFolder url="file://$MODULE_DIR$/test" isTestSource="true" />
       <excludeFolder url="file://$MODULE_DIR$/build" />
     </content>
-    <orderEntry type="jdk" jdkName="openjdk-11" jdkType="JavaSDK" />
+    <orderEntry type="inheritedJdk" />
     <orderEntry type="sourceFolder" forTests="false" />
     <orderEntry type="library" name="KotlinJavaRuntime" level="project" />
-    <orderEntry type="library" name="antlr-runtime-4.7.2" level="project" />
+    <orderEntry type="module" module-name="compilerAst" />
-    <orderEntry type="module" module-name="parser" />
+    <orderEntry type="library" name="jetbrains.kotlinx.cli.jvm" level="project" />
-    <orderEntry type="library" name="unittest-libs" level="project" />
+    <orderEntry type="library" name="michael.bull.kotlin.result.jvm" level="project" />
+    <orderEntry type="module" module-name="codeOptimizers" />
+    <orderEntry type="module" module-name="compilerInterfaces" />
+    <orderEntry type="module" module-name="codeGeneration" />
+    <orderEntry type="library" name="io.kotest.assertions.core.jvm" level="project" />
+    <orderEntry type="library" name="io.kotest.runner.junit5.jvm" level="project" />
+    <orderEntry type="library" name="antlr.antlr4" level="project" />
   </component>
 </module>

compiler/res/.editorconfig

@@ -0,0 +1,20 @@
+root = true
+
+[*]
+charset = utf-8
+end_of_line = lf
+indent_size = 4
+indent_style = space
+insert_final_newline = true
+max_line_length = 120
+tab_width = 8
+trim_trailing_whitespace = true
+ij_smart_tabs = true
+
+[*.p8]
+indent_size = 4
+indent_style = space
+
+[*.asm]
+indent_size = 8
+indent_style = tab

compiler/res/prog8lib/c128/floats.asm

@@ -0,0 +1,683 @@
+; --- low level floating point assembly routines for the C128
+;     these are almost all identical to the C64 except for a few details
+;     so we have to have a separate library file for the C128 unfortunately.
+
+
+FL_ONE_const	.byte  129     			; 1.0
+FL_ZERO_const	.byte  0,0,0,0,0		; 0.0
+FL_LOG2_const	.byte  $80, $31, $72, $17, $f8	; log(2)
+
+
+floats_store_reg	.byte  0		; temp storage
+
+
+ub2float	.proc
+		; -- convert ubyte in SCRATCH_ZPB1 to float at address A/Y
+		;    clobbers A, Y
+		stx  P8ZP_SCRATCH_REG
+		sta  P8ZP_SCRATCH_W2
+		sty  P8ZP_SCRATCH_W2+1
+		ldy  P8ZP_SCRATCH_B1
+		lda  #0
+		jsr  GIVAYF
+_fac_to_mem	ldx  P8ZP_SCRATCH_W2
+		ldy  P8ZP_SCRATCH_W2+1
+		jsr  MOVMF
+		ldx  P8ZP_SCRATCH_REG
+		rts
+		.pend
+
+b2float		.proc
+		; -- convert byte in SCRATCH_ZPB1 to float at address A/Y
+		;    clobbers A, Y
+		stx  P8ZP_SCRATCH_REG
+		sta  P8ZP_SCRATCH_W2
+		sty  P8ZP_SCRATCH_W2+1
+		lda  P8ZP_SCRATCH_B1
+		jsr  FREADSA
+		jmp  ub2float._fac_to_mem
+		.pend
+
+uw2float	.proc
+		; -- convert uword in SCRATCH_ZPWORD1 to float at address A/Y
+		stx  P8ZP_SCRATCH_REG
+		sta  P8ZP_SCRATCH_W2
+		sty  P8ZP_SCRATCH_W2+1
+		lda  P8ZP_SCRATCH_W1
+		ldy  P8ZP_SCRATCH_W1+1
+		jsr  GIVUAYFAY
+		jmp  ub2float._fac_to_mem
+		.pend
+
+w2float		.proc
+		; -- convert word in SCRATCH_ZPWORD1 to float at address A/Y
+		stx  P8ZP_SCRATCH_REG
+		sta  P8ZP_SCRATCH_W2
+		sty  P8ZP_SCRATCH_W2+1
+		ldy  P8ZP_SCRATCH_W1
+		lda  P8ZP_SCRATCH_W1+1
+		jsr  GIVAYF
+		jmp  ub2float._fac_to_mem
+		.pend
+
+
+cast_from_uw	.proc
+		; -- uword in A/Y into float var at (P8ZP_SCRATCH_W2)
+		stx  P8ZP_SCRATCH_REG
+		jsr  GIVUAYFAY
+		jmp  ub2float._fac_to_mem
+		.pend
+
+
+cast_from_w	.proc
+		; -- word in A/Y into float var at (P8ZP_SCRATCH_W2)
+		stx  P8ZP_SCRATCH_REG
+		jsr  GIVAYFAY
+		jmp  ub2float._fac_to_mem
+		.pend
+
+
+cast_from_ub	.proc
+		; -- ubyte in Y into float var at (P8ZP_SCRATCH_W2)
+		stx  P8ZP_SCRATCH_REG
+		jsr  FREADUY
+		jmp  ub2float._fac_to_mem
+		.pend
+
+
+cast_from_b	.proc
+		; -- byte in A into float var at (P8ZP_SCRATCH_W2)
+		stx  P8ZP_SCRATCH_REG
+		jsr  FREADSA
+		jmp  ub2float._fac_to_mem
+		.pend
+
+cast_as_uw_into_ya	.proc               ; also used for float 2 ub
+		; -- cast float at A/Y to uword into Y/A
+		jsr  MOVFM
+		jmp  cast_FAC1_as_uw_into_ya
+		.pend
+
+cast_as_w_into_ay	.proc               ; also used for float 2 b
+		; -- cast float at A/Y to word into A/Y
+		jsr  MOVFM
+		jmp  cast_FAC1_as_w_into_ay
+		.pend
+
+cast_FAC1_as_uw_into_ya	.proc               ; also used for float 2 ub
+		; -- cast fac1 to uword into Y/A
+		stx  P8ZP_SCRATCH_REG
+		jsr  GETADR     ; into Y/A
+		ldx  P8ZP_SCRATCH_REG
+		rts
+		.pend
+
+cast_FAC1_as_w_into_ay	.proc               ; also used for float 2 b
+		; -- cast fac1 to word into A/Y
+		stx  P8ZP_SCRATCH_REG
+		jsr  AYINT
+		ldy  $66
+		lda  $67
+		ldx  P8ZP_SCRATCH_REG
+		rts
+		.pend
+
+
+stack_b2float	.proc
+		; -- b2float operating on the stack
+		inx
+		lda  P8ESTACK_LO,x
+		stx  P8ZP_SCRATCH_REG
+		jsr  FREADSA
+		jmp  push_fac1._internal
+		.pend
+
+stack_w2float	.proc
+		; -- w2float operating on the stack
+		inx
+		ldy  P8ESTACK_LO,x
+		lda  P8ESTACK_HI,x
+		stx  P8ZP_SCRATCH_REG
+		jsr  GIVAYF
+		jmp  push_fac1._internal
+		.pend
+
+stack_ub2float	.proc
+		; -- ub2float operating on the stack
+		inx
+		lda  P8ESTACK_LO,x
+		stx  P8ZP_SCRATCH_REG
+		tay
+		lda  #0
+		jsr  GIVAYF
+		jmp  push_fac1._internal
+		.pend
+
+stack_uw2float	.proc
+		; -- uw2float operating on the stack
+		inx
+		lda  P8ESTACK_LO,x
+		ldy  P8ESTACK_HI,x
+		stx  P8ZP_SCRATCH_REG
+		jsr  GIVUAYFAY
+		jmp  push_fac1._internal
+		.pend
+
+stack_float2w	.proc               ; also used for float2b
+		jsr  pop_float_fac1
+		stx  P8ZP_SCRATCH_REG
+		jsr  AYINT
+		ldx  P8ZP_SCRATCH_REG
+		lda  $66
+		sta  P8ESTACK_HI,x
+		lda  $67
+		sta  P8ESTACK_LO,x
+		dex
+		rts
+		.pend
+
+stack_float2uw	.proc               ; also used for float2ub
+		jsr  pop_float_fac1
+		stx  P8ZP_SCRATCH_REG
+		jsr  GETADR
+		ldx  P8ZP_SCRATCH_REG
+		sta  P8ESTACK_HI,x
+		tya
+		sta  P8ESTACK_LO,x
+		dex
+		rts
+		.pend
+
+push_float	.proc
+		; ---- push mflpt5 in A/Y onto stack
+		; (taking 3 stack positions = 6 bytes of which 1 is padding)
+		sta  P8ZP_SCRATCH_W1
+		sty  P8ZP_SCRATCH_W1+1
+		ldy  #0
+		lda  (P8ZP_SCRATCH_W1),y
+		sta  P8ESTACK_LO,x
+		iny
+		lda  (P8ZP_SCRATCH_W1),y
+		sta  P8ESTACK_HI,x
+		dex
+		iny
+		lda  (P8ZP_SCRATCH_W1),y
+		sta  P8ESTACK_LO,x
+		iny
+		lda  (P8ZP_SCRATCH_W1),y
+		sta  P8ESTACK_HI,x
+		dex
+		iny
+		lda  (P8ZP_SCRATCH_W1),y
+		sta  P8ESTACK_LO,x
+		dex
+		rts
+		.pend
+
+pop_float	.proc
+		; ---- pops mflpt5 from stack to memory A/Y
+		; (frees 3 stack positions = 6 bytes of which 1 is padding)
+		sta  P8ZP_SCRATCH_W1
+		sty  P8ZP_SCRATCH_W1+1
+		ldy  #4
+		inx
+		lda  P8ESTACK_LO,x
+		sta  (P8ZP_SCRATCH_W1),y
+		dey
+		inx
+		lda  P8ESTACK_HI,x
+		sta  (P8ZP_SCRATCH_W1),y
+		dey
+		lda  P8ESTACK_LO,x
+		sta  (P8ZP_SCRATCH_W1),y
+		dey
+		inx
+		lda  P8ESTACK_HI,x
+		sta  (P8ZP_SCRATCH_W1),y
+		dey
+		lda  P8ESTACK_LO,x
+		sta  (P8ZP_SCRATCH_W1),y
+		rts
+		.pend
+
+pop_float_fac1	.proc
+		; -- pops float from stack into FAC1
+		lda  #<fmath_float1
+		ldy  #>fmath_float1
+		jsr  pop_float
+		lda  #<fmath_float1
+		ldy  #>fmath_float1
+		jmp  MOVFM
+		.pend
+
+copy_float	.proc
+		; -- copies the 5 bytes of the mflt value pointed to by SCRATCH_ZPWORD1,
+		;    into the 5 bytes pointed to by A/Y.  Clobbers A,Y.
+		sta  _target+1
+		sty  _target+2
+		ldy  #4
+_loop		lda  (P8ZP_SCRATCH_W1),y
+_target		sta  $ffff,y			; modified
+		dey
+		bpl  _loop
+		rts
+		.pend
+
+inc_var_f	.proc
+		; -- add 1 to float pointed to by A/Y
+		sta  P8ZP_SCRATCH_W1
+		sty  P8ZP_SCRATCH_W1+1
+		stx  P8ZP_SCRATCH_REG
+		jsr  MOVFM
+		lda  #<FL_ONE_const
+		ldy  #>FL_ONE_const
+		jsr  FADD
+		ldx  P8ZP_SCRATCH_W1
+		ldy  P8ZP_SCRATCH_W1+1
+		jsr  MOVMF
+		ldx  P8ZP_SCRATCH_REG
+		rts
+		.pend
+
+dec_var_f	.proc
+		; -- subtract 1 from float pointed to by A/Y
+		sta  P8ZP_SCRATCH_W1
+		sty  P8ZP_SCRATCH_W1+1
+		stx  P8ZP_SCRATCH_REG
+		lda  #<FL_ONE_const
+		ldy  #>FL_ONE_const
+		jsr  MOVFM
+		lda  P8ZP_SCRATCH_W1
+		ldy  P8ZP_SCRATCH_W1+1
+		jsr  FSUB
+		ldx  P8ZP_SCRATCH_W1
+		ldy  P8ZP_SCRATCH_W1+1
+		jsr  MOVMF
+		ldx  P8ZP_SCRATCH_REG
+		rts
+		.pend
+
+
+pop_2_floats_f2_in_fac1	.proc
+		; -- pop 2 floats from stack, load the second one in FAC1 as well
+		lda  #<fmath_float2
+		ldy  #>fmath_float2
+		jsr  pop_float
+		lda  #<fmath_float1
+		ldy  #>fmath_float1
+		jsr  pop_float
+		lda  #<fmath_float2
+		ldy  #>fmath_float2
+		jmp  MOVFM
+		.pend
+
+
+fmath_float1	.byte 0,0,0,0,0	; storage for a mflpt5 value
+fmath_float2	.byte 0,0,0,0,0	; storage for a mflpt5 value
+
+
+push_fac1	.proc
+		; -- push the float in FAC1 onto the stack
+		stx  P8ZP_SCRATCH_REG
+_internal	ldx  #<fmath_float1
+		ldy  #>fmath_float1
+		jsr  MOVMF
+		lda  #<fmath_float1
+		ldy  #>fmath_float1
+		ldx  P8ZP_SCRATCH_REG
+		jmp  push_float
+		.pend
+
+
+pow_f		.proc
+		; -- push f1 ** f2 on stack
+		lda  #<fmath_float2
+		ldy  #>fmath_float2
+		jsr  pop_float
+		lda  #<fmath_float1
+		ldy  #>fmath_float1
+		jsr  pop_float
+		stx  P8ZP_SCRATCH_REG
+		lda  #<fmath_float1
+		ldy  #>fmath_float1
+		jsr  ROMUPK		; fac2 = float1
+		lda  #<fmath_float2
+		ldy  #>fmath_float2
+		jsr  FPWR
+		jmp  push_fac1._internal
+		.pend
+
+div_f		.proc
+		; -- push f1/f2 on stack
+		jsr  pop_2_floats_f2_in_fac1
+		stx  P8ZP_SCRATCH_REG
+		lda  #<fmath_float1
+		ldy  #>fmath_float1
+		jsr  FDIV
+		jmp  push_fac1._internal
+		.pend
+
+add_f		.proc
+		; -- push f1+f2 on stack
+		jsr  pop_2_floats_f2_in_fac1
+		stx  P8ZP_SCRATCH_REG
+		lda  #<fmath_float1
+		ldy  #>fmath_float1
+		jsr  FADD
+		jmp  push_fac1._internal
+		.pend
+
+sub_f		.proc
+		; -- push f1-f2 on stack
+		jsr  pop_2_floats_f2_in_fac1
+		stx  P8ZP_SCRATCH_REG
+		lda  #<fmath_float1
+		ldy  #>fmath_float1
+		jsr  FSUB
+		jmp  push_fac1._internal
+		.pend
+
+mul_f		.proc
+		; -- push f1*f2 on stack
+		jsr  pop_2_floats_f2_in_fac1
+		stx  P8ZP_SCRATCH_REG
+		lda  #<fmath_float1
+		ldy  #>fmath_float1
+		jsr  FMULT
+		jmp  push_fac1._internal
+		.pend
+
+neg_f		.proc
+		; -- toggle the sign bit on the stack
+		lda  P8ESTACK_HI+3,x
+		eor  #$80
+		sta  P8ESTACK_HI+3,x
+		rts
+		.pend
+
+var_fac1_less_f	.proc
+		; -- is the float in FAC1 < the variable AY?
+		stx  P8ZP_SCRATCH_REG
+		jsr  FCOMP
+		ldx  P8ZP_SCRATCH_REG
+		cmp  #255
+		beq  +
+		lda  #0
+		rts
++		lda  #1
+		rts
+		.pend
+
+var_fac1_lesseq_f	.proc
+		; -- is the float in FAC1 <= the variable AY?
+		stx  P8ZP_SCRATCH_REG
+		jsr  FCOMP
+		ldx  P8ZP_SCRATCH_REG
+		cmp  #0
+		beq  +
+		cmp  #255
+		beq  +
+		lda  #0
+		rts
++		lda  #1
+		rts
+		.pend
+
+var_fac1_greater_f	.proc
+		; -- is the float in FAC1 > the variable AY?
+		stx  P8ZP_SCRATCH_REG
+		jsr  FCOMP
+		ldx  P8ZP_SCRATCH_REG
+		cmp  #1
+		beq  +
+		lda  #0
+		rts
++		lda  #1
+		rts
+		.pend
+
+var_fac1_greatereq_f	.proc
+		; -- is the float in FAC1 >= the variable AY?
+		stx  P8ZP_SCRATCH_REG
+		jsr  FCOMP
+		ldx  P8ZP_SCRATCH_REG
+		cmp  #0
+		beq  +
+		cmp  #1
+		beq  +
+		lda  #0
+		rts
++		lda  #1
+		rts
+		.pend
+
+var_fac1_notequal_f	.proc
+		; -- are the floats numbers in FAC1 and the variable AY *not* identical?
+		stx  P8ZP_SCRATCH_REG
+		jsr  FCOMP
+		ldx  P8ZP_SCRATCH_REG
+		and  #1
+		rts
+		.pend
+
+vars_equal_f	.proc
+		; -- are the mflpt5 numbers in P8ZP_SCRATCH_W1 and AY identical?
+		sta  P8ZP_SCRATCH_W2
+		sty  P8ZP_SCRATCH_W2+1
+		ldy  #0
+		lda  (P8ZP_SCRATCH_W1),y
+		cmp  (P8ZP_SCRATCH_W2),y
+		bne  _false
+		iny
+		lda  (P8ZP_SCRATCH_W1),y
+		cmp  (P8ZP_SCRATCH_W2),y
+		bne  _false
+		iny
+		lda  (P8ZP_SCRATCH_W1),y
+		cmp  (P8ZP_SCRATCH_W2),y
+		bne  _false
+		iny
+		lda  (P8ZP_SCRATCH_W1),y
+		cmp  (P8ZP_SCRATCH_W2),y
+		bne  _false
+		iny
+		lda  (P8ZP_SCRATCH_W1),y
+		cmp  (P8ZP_SCRATCH_W2),y
+		bne  _false
+		lda  #1
+		rts
+_false		lda  #0
+		rts
+		.pend
+
+equal_f		.proc
+		; -- are the two mflpt5 numbers on the stack identical?
+		inx
+		inx
+		inx
+		inx
+		lda  P8ESTACK_LO-3,x
+		cmp  P8ESTACK_LO,x
+		bne  _equals_false
+		lda  P8ESTACK_LO-2,x
+		cmp  P8ESTACK_LO+1,x
+		bne  _equals_false
+		lda  P8ESTACK_LO-1,x
+		cmp  P8ESTACK_LO+2,x
+		bne  _equals_false
+		lda  P8ESTACK_HI-2,x
+		cmp  P8ESTACK_HI+1,x
+		bne  _equals_false
+		lda  P8ESTACK_HI-1,x
+		cmp  P8ESTACK_HI+2,x
+		bne  _equals_false
+_equals_true	lda  #1
+_equals_store	inx
+		sta  P8ESTACK_LO+1,x
+		rts
+_equals_false	lda  #0
+		beq  _equals_store
+		.pend
+
+notequal_f	.proc
+		; -- are the two mflpt5 numbers on the stack different?
+		jsr  equal_f
+		eor  #1		; invert the result
+		sta  P8ESTACK_LO+1,x
+		rts
+		.pend
+
+vars_less_f	.proc
+		; -- is float in AY < float in P8ZP_SCRATCH_W2 ?
+		jsr  MOVFM
+		lda  P8ZP_SCRATCH_W2
+		ldy  P8ZP_SCRATCH_W2+1
+		stx  P8ZP_SCRATCH_REG
+		jsr  FCOMP
+		ldx  P8ZP_SCRATCH_REG
+		cmp  #255
+		bne  +
+		lda  #1
+		rts
++		lda  #0
+		rts
+		.pend
+
+vars_lesseq_f	.proc
+		; -- is float in AY <= float in P8ZP_SCRATCH_W2 ?
+		jsr  MOVFM
+		lda  P8ZP_SCRATCH_W2
+		ldy  P8ZP_SCRATCH_W2+1
+		stx  P8ZP_SCRATCH_REG
+		jsr  FCOMP
+		ldx  P8ZP_SCRATCH_REG
+		cmp  #255
+		bne  +
+-		lda  #1
+		rts
++		cmp  #0
+		beq  -
+		lda  #0
+		rts
+		.pend
+
+less_f		.proc
+		; -- is f1 < f2?
+		jsr  compare_floats
+		cmp  #255
+		beq  compare_floats._return_true
+		bne  compare_floats._return_false
+		.pend
+
+
+lesseq_f	.proc
+		; -- is f1 <= f2?
+		jsr  compare_floats
+		cmp  #255
+		beq  compare_floats._return_true
+		cmp  #0
+		beq  compare_floats._return_true
+		bne  compare_floats._return_false
+		.pend
+
+greater_f	.proc
+		; -- is f1 > f2?
+		jsr  compare_floats
+		cmp  #1
+		beq  compare_floats._return_true
+		bne  compare_floats._return_false
+		.pend
+
+greatereq_f	.proc
+		; -- is f1 >= f2?
+		jsr  compare_floats
+		cmp  #1
+		beq  compare_floats._return_true
+		cmp  #0
+		beq  compare_floats._return_true
+		bne  compare_floats._return_false
+		.pend
+
+compare_floats	.proc
+		lda  #<fmath_float2
+		ldy  #>fmath_float2
+		jsr  pop_float
+		lda  #<fmath_float1
+		ldy  #>fmath_float1
+		jsr  pop_float
+		lda  #<fmath_float1
+		ldy  #>fmath_float1
+		jsr  MOVFM		; fac1 = flt1
+		lda  #<fmath_float2
+		ldy  #>fmath_float2
+		stx  P8ZP_SCRATCH_REG
+		jsr  FCOMP		; A = flt1 compared with flt2 (0=equal, 1=flt1>flt2, 255=flt1<flt2)
+		ldx  P8ZP_SCRATCH_REG
+		rts
+_return_false	lda  #0
+_return_result  sta  P8ESTACK_LO,x
+		dex
+		rts
+_return_true	lda  #1
+		bne  _return_result
+		.pend
+
+set_array_float_from_fac1	.proc
+		; -- set the float in FAC1 in the array (index in A, array in P8ZP_SCRATCH_W1)
+		sta  P8ZP_SCRATCH_B1
+		asl  a
+		asl  a
+		clc
+		adc  P8ZP_SCRATCH_B1
+		ldy  P8ZP_SCRATCH_W1+1
+		clc
+		adc  P8ZP_SCRATCH_W1
+		bcc  +
+		iny
++		stx  floats_store_reg
+		tax
+		jsr  MOVMF
+		ldx  floats_store_reg
+		rts
+		.pend
+
+
+set_0_array_float	.proc
+		; -- set a float in an array to zero (index in A, array in P8ZP_SCRATCH_W1)
+		sta  P8ZP_SCRATCH_B1
+		asl  a
+		asl  a
+		clc
+		adc  P8ZP_SCRATCH_B1
+		tay
+		lda  #0
+		sta  (P8ZP_SCRATCH_W1),y
+		iny
+		sta  (P8ZP_SCRATCH_W1),y
+		iny
+		sta  (P8ZP_SCRATCH_W1),y
+		iny
+		sta  (P8ZP_SCRATCH_W1),y
+		iny
+		sta  (P8ZP_SCRATCH_W1),y
+		rts
+		.pend
+
+
+set_array_float		.proc
+		; -- set a float in an array to a value (index in A, float in P8ZP_SCRATCH_W1, array in P8ZP_SCRATCH_W2)
+		sta  P8ZP_SCRATCH_B1
+		asl  a
+		asl  a
+		clc
+		adc  P8ZP_SCRATCH_B1
+		adc  P8ZP_SCRATCH_W2
+		ldy  P8ZP_SCRATCH_W2+1
+		bcc  +
+		iny
++		jmp  copy_float
+			; -- copies the 5 bytes of the mflt value pointed to by SCRATCH_ZPWORD1,
+			;    into the 5 bytes pointed to by A/Y.  Clobbers A,Y.
+		.pend
+
+

compiler/res/prog8lib/c128/floats.p8

@@ -0,0 +1,159 @@
+; Prog8 definitions for floating point handling on the Commodore 128
+;
+; Written by Irmen de Jong (irmen@razorvine.net) - license: GNU GPL 3.0
+
+%option enable_floats
+
+floats {
+	; ---- this block contains C-128 compatible floating point related functions ----
+
+        const float  PI     = 3.141592653589793
+        const float  TWOPI  = 6.283185307179586
+
+        float  tempvar_swap_float     ; used for some swap() operations
+
+
+; ---- ROM float functions ----
+
+		; note: the fac1 and fac2 are working registers and take 6 bytes each,
+		; floats in memory  (and rom) are stored in 5-byte MFLPT packed format.
+
+; note: fac1/2 might get clobbered even if not mentioned in the function's name.
+; note: for subtraction and division, the left operand is in fac2, the right operand in fac1.
+
+romsub $af00 = AYINT() clobbers(A,X,Y)          ; fac1-> signed word in 102-103 ($66-$67) MSB FIRST. (might throw ILLEGAL QUANTITY)
+
+; GIVAYF: signed word in Y/A (note different lsb/msb order) -> float in fac1
+; there is also floats.GIVUAYFAY - unsigned word in A/Y (lo/hi) to fac1
+; (tip: use GIVAYFAY to use A/Y input; lo/hi switched to normal order)
+romsub $af03 = GIVAYF(ubyte lo @ Y, ubyte hi @ A) clobbers(A,X,Y)
+romsub $af09 = VAL(ubyte length @ A) clobbers(A,X,Y)       ; str -> fac1, $24/25 must point to string in bank1, A=string length   Don't call this from bank0
+
+; fac1 -> unsigned word in Y/A (might throw ILLEGAL QUANTITY) (result also in $16/17)
+; (tip: use GETADRAY to get A/Y output; lo/hi switched to normal little endian order)
+romsub $af0c = GETADR() clobbers(X) -> ubyte @ Y, ubyte @ A
+
+romsub $af12 = FSUB(uword mflpt @ AY) clobbers(A,X,Y)       ; fac1 = mflpt from A/Y - fac1
+romsub $af15 = FSUBT() clobbers(A,X,Y)                      ; fac1 = fac2-fac1   mind the order of the operands
+romsub $af18 = FADD(uword mflpt @ AY) clobbers(A,X,Y)       ; fac1 += mflpt value from A/Y in bank 1
+romsub $af1b = FADDT() clobbers(A,X,Y)                      ; fac1 += fac2
+romsub $af2a = LOG() clobbers(A,X,Y)                        ; fac1 = LN(fac1)  (natural log)
+romsub $af1e = FMULT(uword mflpt @ AY) clobbers(A,X,Y)      ; fac1 *= mflpt value from A/Y
+romsub $af21 = FMULTT() clobbers(A,X,Y)                     ; fac1 *= fac2
+romsub $af5a = CONUPK(uword mflpt @ AY) clobbers(A,X,Y)     ; load mflpt value from memory bank 1  in A/Y into fac2
+romsub $af5d = ROMUPK(uword mflpt @ AY) clobbers(A,X,Y)     ; load mflpt value from memory in current bank in A/Y into fac2
+romsub $af24 = FDIV(uword mflpt @ AY) clobbers(A,X,Y)       ; fac1 = mflpt in A/Y / fac1  (remainder in fac2)
+romsub $af27 = FDIVT() clobbers(A,X,Y)                      ; fac1 = fac2/fac1  (remainder in fac2)  mind the order of the operands
+
+romsub $af63 = MOVFM(uword mflpt @ AY) clobbers(A,X,Y)      ; load mflpt value from memory  in A/Y into fac1
+romsub $af60 = MOVFRM() clobbers(A,X,Y)                     ; load mflpt value from memory  in $24/$25 into fac2
+romsub $af66 = MOVMF(uword mflpt @ XY) clobbers(A,X,Y)      ; store fac1 to memory  X/Y as 5-byte mflpt
+romsub $af69 = MOVFA() clobbers(A,X)                        ; copy fac2 to fac1
+romsub $af6c = MOVAF() clobbers(A,X)                        ; copy fac1 to fac2
+romsub $af6c = MOVEF() clobbers(A,X)                        ; copy fac1 to fac2
+romsub $af51 = SIGN() clobbers(X,Y) -> ubyte @ A            ; SIGN(fac1) to A, $ff, $0, $1 for negative, zero, positive
+romsub $af4e = ABS() clobbers(A,X,Y)                        ; fac1 = ABS(fac1)
+romsub $af54 = FCOMP(uword mflpt @ AY) clobbers(X,Y) -> ubyte @ A   ; A = compare fac1 to mflpt in A/Y, 0=equal 1=fac1 is greater, 255=fac1 is less than
+romsub $af2d = INT() clobbers(A,X,Y)                        ; INT() truncates, use FADDH first to round instead of trunc
+romsub $af06 = FOUT() clobbers(X) -> uword @ AY             ; fac1 -> string, address returned in AY ($0100)
+romsub $af30 = SQR() clobbers(A,X,Y)                        ; fac1 = SQRT(fac1)
+romsub $af36 = FPWR(uword mflpt @ AY) clobbers(A,X,Y)       ; fac1 = fac2 ** mflpt from A/Y
+romsub $af39 = FPWRT() clobbers(A,X,Y)                      ; fac1 = fac2 ** fac1
+romsub $af33 = NEGOP() clobbers(A)                          ; switch the sign of fac1 (fac1 = -fac1)
+romsub $af3c = EXP() clobbers(A,X,Y)                        ; fac1 = EXP(fac1)  (e ** fac1)
+romsub $af57 = RND() clobbers(A,X,Y)                        ; fac1 = RND(fac1) float random number generator
+romsub $af3f = COS() clobbers(A,X,Y)                        ; fac1 = COS(fac1)
+romsub $af42 = SIN() clobbers(A,X,Y)                        ; fac1 = SIN(fac1)
+romsub $af45 = TAN() clobbers(A,X,Y)                        ; fac1 = TAN(fac1)
+romsub $af48 = ATN() clobbers(A,X,Y)                        ; fac1 = ATN(fac1)
+
+
+asmsub  FREADSA  (byte value @A) clobbers(A,X,Y) {
+    ; ---- 8 bit signed A -> float in fac1
+    %asm {{
+        tay
+        bpl  +
+        lda  #$ff
+        jmp  GIVAYF
++       lda  #0
+        jmp  GIVAYF
+    }}
+}
+
+asmsub  GIVUAYFAY  (uword value @ AY) clobbers(A,X,Y)  {
+	; ---- unsigned 16 bit word in A/Y (lo/hi) to fac1
+	%asm {{
+            stx  P8ZP_SCRATCH_REG
+            sta  _tmp
+            sty  P8ZP_SCRATCH_B1
+            tya
+            ldy  _tmp
+            jsr  GIVAYF                 ; load it as signed... correct afterwards
+            lda  P8ZP_SCRATCH_B1
+            bpl  +
+            lda  #<_flt65536
+            ldy  #>_flt65536
+            jsr  ROMUPK
+            jsr  FADDT
++           ldx  P8ZP_SCRATCH_REG
+            rts
+_tmp        .byte 0
+_flt65536   .byte 145,0,0,0,0       ; 65536.0
+	}}
+}
+
+
+asmsub  GIVAYFAY  (uword value @ AY) clobbers(A,X,Y)  {
+	; ---- signed 16 bit word in A/Y (lo/hi) to float in fac1
+	%asm {{
+		sta  P8ZP_SCRATCH_B1
+		tya
+		ldy  P8ZP_SCRATCH_B1
+		jmp  GIVAYF		; this uses the inverse order, Y/A
+	}}
+}
+
+asmsub  GETADRAY  () clobbers(X) -> uword @ AY  {
+	; ---- fac1 to unsigned word in A/Y
+	%asm {{
+		jsr  GETADR		; this uses the inverse order, Y/A
+		sta  P8ZP_SCRATCH_B1
+		tya
+		ldy  P8ZP_SCRATCH_B1
+		rts
+	}}
+}
+
+asmsub  FREADUY (ubyte value @Y) {
+    ; -- 8 bit unsigned Y -> float in fac1
+    %asm {{
+        lda  #0
+        jmp  GIVAYF
+    }}
+}
+
+sub  print_f  (float value) {
+	; ---- prints the floating point value (without a newline).
+	%asm {{
+		stx  P8ZP_SCRATCH_REG
+		lda  #<value
+		ldy  #>value
+		jsr  MOVFM		; load float into fac1
+		jsr  FOUT		; fac1 to string in A/Y
+		sta  P8ZP_SCRATCH_W1
+		sty  P8ZP_SCRATCH_W1+1
+		ldy  #0
+-		lda  (P8ZP_SCRATCH_W1),y
+		beq  +
+		jsr  c64.CHROUT
+		iny
+		bne  -
++		ldx  P8ZP_SCRATCH_REG
+		rts
+	}}
+}
+
+%asminclude "library:c128/floats.asm"
+%asminclude "library:c64/floats_funcs.asm"
+
+}

compiler/res/prog8lib/c128/graphics.p8

@@ -0,0 +1,60 @@
+%import syslib
+%import textio
+
+; Bitmap pixel graphics module for the Commodore 128
+
+; TODO c128 actually implement the graphics routines. Ideally a way to 'borrow' the code form the C64 version without just copy-pasting that here?
+
+graphics {
+    const uword WIDTH = 320
+    const ubyte HEIGHT = 200
+
+    sub enable_bitmap_mode() {
+        ; enable bitmap screen, erase it and set colors to black/white.
+        ; TODO
+    }
+
+    sub disable_bitmap_mode() {
+        ; enables text mode, erase the text screen, color white
+        ; TODO
+    }
+
+
+    sub clear_screen(ubyte pixelcolor, ubyte bgcolor) {
+        ; TODO
+    }
+
+    sub line(uword @zp x1, ubyte @zp y1, uword @zp x2, ubyte @zp y2) {
+        ; TODO
+    }
+
+    sub fillrect(uword x, uword y, uword width, uword height) {
+        ; TODO
+    }
+
+    sub rect(uword x, uword y, uword width, uword height) {
+        ; TODO
+    }
+
+    sub horizontal_line(uword x, uword y, uword length) {
+        ; TODO
+    }
+
+    sub vertical_line(uword x, uword y, uword height) {
+        ; TODO
+    }
+
+    sub circle(uword xcenter, ubyte ycenter, ubyte radius) {
+        ; TODO
+    }
+
+    sub disc(uword xcenter, ubyte ycenter, ubyte radius) {
+        ; TODO
+    }
+
+    inline asmsub  plot(uword plotx @R0, uword ploty @R1) clobbers(A, X, Y) {
+        %asm {{
+            nop     ; TODO
+        }}
+    }
+}

compiler/res/prog8lib/c128/syslib.p8

@@ -0,0 +1,796 @@
+; Prog8 definitions for the Commodore-128
+; Including memory registers, I/O registers, Basic and Kernal subroutines.
+;
+; Written by Irmen de Jong (irmen@razorvine.net) - license: GNU GPL 3.0
+;
+
+c64 {
+
+        &ubyte  TIME_HI         = $a0       ; software jiffy clock, hi byte
+        &ubyte  TIME_MID        = $a1       ;  .. mid byte
+        &ubyte  TIME_LO         = $a2       ;    .. lo byte. Updated by IRQ every 1/60 sec
+        &ubyte  STATUS          = $90       ; kernal status variable for I/O
+        &ubyte  STKEY           = $91       ; various keyboard statuses (updated by IRQ)
+        ;;&ubyte  SFDX            = $cb       ; current key pressed (matrix value) (updated by IRQ)     // TODO c128 ??
+
+        &ubyte  COLOR           = $00f1     ; cursor color
+        ;;&ubyte  HIBASE          = $0288     ; screen base address / 256 (hi-byte of screen memory address)        // TODO c128 ??
+        &uword  CINV            = $0314     ; IRQ vector (in ram)
+        &uword  CBINV           = $0316     ; BRK vector (in ram)
+        &uword  NMINV           = $0318     ; NMI vector (in ram)
+        &uword  NMI_VEC         = $FFFA     ; 6502 nmi vector, determined by the kernal if banked in
+        &uword  RESET_VEC       = $FFFC     ; 6502 reset vector, determined by the kernal if banked in
+        &uword  IRQ_VEC         = $FFFE     ; 6502 interrupt vector, determined by the kernal if banked in
+
+        ; the default addresses for the character screen chars and colors
+        const  uword  Screen    = $0400     ; to have this as an array[40*25] the compiler would have to support array size > 255
+        const  uword  Colors    = $d800     ; to have this as an array[40*25] the compiler would have to support array size > 255
+
+        ; the default locations of the 8 sprite pointers (store address of sprite / 64)
+        &ubyte  SPRPTR0         = 2040
+        &ubyte  SPRPTR1         = 2041
+        &ubyte  SPRPTR2         = 2042
+        &ubyte  SPRPTR3         = 2043
+        &ubyte  SPRPTR4         = 2044
+        &ubyte  SPRPTR5         = 2045
+        &ubyte  SPRPTR6         = 2046
+        &ubyte  SPRPTR7         = 2047
+        &ubyte[8]  SPRPTR       = 2040      ; the 8 sprite pointers as an array.
+
+
+; ---- VIC-II 6567/6569/856x registers ----
+
+        &ubyte  SP0X            = $d000
+        &ubyte  SP0Y            = $d001
+        &ubyte  SP1X            = $d002
+        &ubyte  SP1Y            = $d003
+        &ubyte  SP2X            = $d004
+        &ubyte  SP2Y            = $d005
+        &ubyte  SP3X            = $d006
+        &ubyte  SP3Y            = $d007
+        &ubyte  SP4X            = $d008
+        &ubyte  SP4Y            = $d009
+        &ubyte  SP5X            = $d00a
+        &ubyte  SP5Y            = $d00b
+        &ubyte  SP6X            = $d00c
+        &ubyte  SP6Y            = $d00d
+        &ubyte  SP7X            = $d00e
+        &ubyte  SP7Y            = $d00f
+        &ubyte[16]  SPXY        = $d000        ; the 8 sprite X and Y registers as an array.
+        &uword[8]  SPXYW        = $d000        ; the 8 sprite X and Y registers as a combined xy word array.
+
+        &ubyte  MSIGX           = $d010
+        &ubyte  SCROLY          = $d011
+        &ubyte  RASTER          = $d012
+        &ubyte  LPENX           = $d013
+        &ubyte  LPENY           = $d014
+        &ubyte  SPENA           = $d015
+        &ubyte  SCROLX          = $d016
+        &ubyte  YXPAND          = $d017
+        &ubyte  VMCSB           = $d018
+        &ubyte  VICIRQ          = $d019
+        &ubyte  IREQMASK        = $d01a
+        &ubyte  SPBGPR          = $d01b
+        &ubyte  SPMC            = $d01c
+        &ubyte  XXPAND          = $d01d
+        &ubyte  SPSPCL          = $d01e
+        &ubyte  SPBGCL          = $d01f
+
+        &ubyte  EXTCOL          = $d020        ; border color
+        &ubyte  BGCOL0          = $d021        ; screen color
+        &ubyte  BGCOL1          = $d022
+        &ubyte  BGCOL2          = $d023
+        &ubyte  BGCOL4          = $d024
+        &ubyte  SPMC0           = $d025
+        &ubyte  SPMC1           = $d026
+        &ubyte  SP0COL          = $d027
+        &ubyte  SP1COL          = $d028
+        &ubyte  SP2COL          = $d029
+        &ubyte  SP3COL          = $d02a
+        &ubyte  SP4COL          = $d02b
+        &ubyte  SP5COL          = $d02c
+        &ubyte  SP6COL          = $d02d
+        &ubyte  SP7COL          = $d02e
+        &ubyte[8]  SPCOL        = $d027
+
+
+; ---- end of VIC-II registers ----
+
+; ---- CIA 6526 1 & 2 registers ----
+
+        &ubyte  CIA1PRA         = $DC00        ; CIA 1 DRA, keyboard column drive (and joystick control port #2)
+        &ubyte  CIA1PRB         = $DC01        ; CIA 1 DRB, keyboard row port (and joystick control port #1)
+        &ubyte  CIA1DDRA        = $DC02        ; CIA 1 DDRA, keyboard column
+        &ubyte  CIA1DDRB        = $DC03        ; CIA 1 DDRB, keyboard row
+        &ubyte  CIA1TAL         = $DC04        ; CIA 1 timer A low byte
+        &ubyte  CIA1TAH         = $DC05        ; CIA 1 timer A high byte
+        &ubyte  CIA1TBL         = $DC06        ; CIA 1 timer B low byte
+        &ubyte  CIA1TBH         = $DC07        ; CIA 1 timer B high byte
+        &ubyte  CIA1TOD10       = $DC08        ; time of day, 1/10 sec.
+        &ubyte  CIA1TODSEC      = $DC09        ; time of day, seconds
+        &ubyte  CIA1TODMMIN     = $DC0A        ; time of day, minutes
+        &ubyte  CIA1TODHR       = $DC0B        ; time of day, hours
+        &ubyte  CIA1SDR         = $DC0C        ; Serial Data Register
+        &ubyte  CIA1ICR         = $DC0D
+        &ubyte  CIA1CRA         = $DC0E
+        &ubyte  CIA1CRB         = $DC0F
+
+        &ubyte  CIA2PRA         = $DD00        ; CIA 2 DRA, serial port and video address
+        &ubyte  CIA2PRB         = $DD01        ; CIA 2 DRB, RS232 port / USERPORT
+        &ubyte  CIA2DDRA        = $DD02        ; CIA 2 DDRA, serial port and video address
+        &ubyte  CIA2DDRB        = $DD03        ; CIA 2 DDRB, RS232 port / USERPORT
+        &ubyte  CIA2TAL         = $DD04        ; CIA 2 timer A low byte
+        &ubyte  CIA2TAH         = $DD05        ; CIA 2 timer A high byte
+        &ubyte  CIA2TBL         = $DD06        ; CIA 2 timer B low byte
+        &ubyte  CIA2TBH         = $DD07        ; CIA 2 timer B high byte
+        &ubyte  CIA2TOD10       = $DD08        ; time of day, 1/10 sec.
+        &ubyte  CIA2TODSEC      = $DD09        ; time of day, seconds
+        &ubyte  CIA2TODMIN      = $DD0A        ; time of day, minutes
+        &ubyte  CIA2TODHR       = $DD0B        ; time of day, hours
+        &ubyte  CIA2SDR         = $DD0C        ; Serial Data Register
+        &ubyte  CIA2ICR         = $DD0D
+        &ubyte  CIA2CRA         = $DD0E
+        &ubyte  CIA2CRB         = $DD0F
+
+; ---- end of CIA registers ----
+
+; ---- SID 6581/8580 registers ----
+
+        &ubyte  FREQLO1         = $D400        ; channel 1 freq lo
+        &ubyte  FREQHI1         = $D401        ; channel 1 freq hi
+        &uword  FREQ1           = $D400        ; channel 1 freq (word)
+        &ubyte  PWLO1           = $D402        ; channel 1 pulse width lo (7-0)
+        &ubyte  PWHI1           = $D403        ; channel 1 pulse width hi (11-8)
+        &uword  PW1             = $D402        ; channel 1 pulse width (word)
+        &ubyte  CR1             = $D404        ; channel 1 voice control register
+        &ubyte  AD1             = $D405        ; channel 1 attack & decay
+        &ubyte  SR1             = $D406        ; channel 1 sustain & release
+        &ubyte  FREQLO2         = $D407        ; channel 2 freq lo
+        &ubyte  FREQHI2         = $D408        ; channel 2 freq hi
+        &uword  FREQ2           = $D407        ; channel 2 freq (word)
+        &ubyte  PWLO2           = $D409        ; channel 2 pulse width lo (7-0)
+        &ubyte  PWHI2           = $D40A        ; channel 2 pulse width hi (11-8)
+        &uword  PW2             = $D409        ; channel 2 pulse width (word)
+        &ubyte  CR2             = $D40B        ; channel 2 voice control register
+        &ubyte  AD2             = $D40C        ; channel 2 attack & decay
+        &ubyte  SR2             = $D40D        ; channel 2 sustain & release
+        &ubyte  FREQLO3         = $D40E        ; channel 3 freq lo
+        &ubyte  FREQHI3         = $D40F        ; channel 3 freq hi
+        &uword  FREQ3           = $D40E        ; channel 3 freq (word)
+        &ubyte  PWLO3           = $D410        ; channel 3 pulse width lo (7-0)
+        &ubyte  PWHI3           = $D411        ; channel 3 pulse width hi (11-8)
+        &uword  PW3             = $D410        ; channel 3 pulse width (word)
+        &ubyte  CR3             = $D412        ; channel 3 voice control register
+        &ubyte  AD3             = $D413        ; channel 3 attack & decay
+        &ubyte  SR3             = $D414        ; channel 3 sustain & release
+        &ubyte  FCLO            = $D415        ; filter cutoff lo (2-0)
+        &ubyte  FCHI            = $D416        ; filter cutoff hi (10-3)
+        &uword  FC              = $D415        ; filter cutoff (word)
+        &ubyte  RESFILT         = $D417        ; filter resonance and routing
+        &ubyte  MVOL            = $D418        ; filter mode and main volume control
+        &ubyte  POTX            = $D419        ; potentiometer X
+        &ubyte  POTY            = $D41A        ; potentiometer Y
+        &ubyte  OSC3            = $D41B        ; channel 3 oscillator value read
+        &ubyte  ENV3            = $D41C        ; channel 3 envelope value read
+
+    ; ---- end of SID registers ----
+
+; ---- kernal routines, these are the same as on the Commodore-64 (hence the same block name) ----
+
+; STROUT --> use txt.print
+; CLEARSCR -> use txt.clear_screen
+; HOMECRSR -> use txt.home or txt.plot
+
+romsub $FA65 = IRQDFRT() clobbers(A,X,Y)                        ; default IRQ routine
+romsub $FF33 = IRQDFEND() clobbers(A,X,Y)                       ; default IRQ end/cleanup
+
+; TODO c128 a bunch of kernal routines are missing here that are specific to the c128
+
+romsub $FF81 = CINT() clobbers(A,X,Y)                           ; (alias: SCINIT) initialize screen editor and video chip
+romsub $FF84 = IOINIT() clobbers(A, X)                          ; initialize I/O devices (CIA, SID, IRQ)
+romsub $FF87 = RAMTAS() clobbers(A,X,Y)                         ; initialize RAM, tape buffer, screen
+romsub $FF8A = RESTOR() clobbers(A,X,Y)                         ; restore default I/O vectors
+romsub $FF8D = VECTOR(uword userptr @ XY, ubyte dir @ Pc) clobbers(A,Y)     ; read/set I/O vector table
+romsub $FF90 = SETMSG(ubyte value @ A)                          ; set Kernal message control flag
+romsub $FF93 = SECOND(ubyte address @ A) clobbers(A)            ; (alias: LSTNSA) send secondary address after LISTEN
+romsub $FF96 = TKSA(ubyte address @ A) clobbers(A)              ; (alias: TALKSA) send secondary address after TALK
+romsub $FF99 = MEMTOP(uword address @ XY, ubyte dir @ Pc) -> uword @ XY     ; read/set top of memory  pointer
+romsub $FF9C = MEMBOT(uword address @ XY, ubyte dir @ Pc) -> uword @ XY     ; read/set bottom of memory  pointer
+romsub $FF9F = SCNKEY() clobbers(A,X,Y)                         ; scan the keyboard
+romsub $FFA2 = SETTMO(ubyte timeout @ A)                        ; set time-out flag for IEEE bus
+romsub $FFA5 = ACPTR() -> ubyte @ A                             ; (alias: IECIN) input byte from serial bus
+romsub $FFA8 = CIOUT(ubyte databyte @ A)                        ; (alias: IECOUT) output byte to serial bus
+romsub $FFAB = UNTLK() clobbers(A)                              ; command serial bus device to UNTALK
+romsub $FFAE = UNLSN() clobbers(A)                              ; command serial bus device to UNLISTEN
+romsub $FFB1 = LISTEN(ubyte device @ A) clobbers(A)             ; command serial bus device to LISTEN
+romsub $FFB4 = TALK(ubyte device @ A) clobbers(A)               ; command serial bus device to TALK
+romsub $FFB7 = READST() -> ubyte @ A                            ; read I/O status word
+romsub $FFBA = SETLFS(ubyte logical @ A, ubyte device @ X, ubyte secondary @ Y)   ; set logical file parameters
+romsub $FFBD = SETNAM(ubyte namelen @ A, str filename @ XY)     ; set filename parameters
+romsub $FFC0 = OPEN() clobbers(X,Y) -> ubyte @Pc, ubyte @A      ; (via 794 ($31A)) open a logical file
+romsub $FFC3 = CLOSE(ubyte logical @ A) clobbers(A,X,Y)         ; (via 796 ($31C)) close a logical file
+romsub $FFC6 = CHKIN(ubyte logical @ X) clobbers(A,X) -> ubyte @Pc    ; (via 798 ($31E)) define an input channel
+romsub $FFC9 = CHKOUT(ubyte logical @ X) clobbers(A,X)          ; (via 800 ($320)) define an output channel
+romsub $FFCC = CLRCHN() clobbers(A,X)                           ; (via 802 ($322)) restore default devices
+romsub $FFCF = CHRIN() clobbers(X, Y) -> ubyte @ A   ; (via 804 ($324)) input a character (for keyboard, read a whole line from the screen) A=byte read.
+romsub $FFD2 = CHROUT(ubyte char @ A)                           ; (via 806 ($326)) output a character
+romsub $FFD5 = LOAD(ubyte verify @ A, uword address @ XY) -> ubyte @Pc, ubyte @ A, uword @ XY     ; (via 816 ($330)) load from device
+romsub $FFD8 = SAVE(ubyte zp_startaddr @ A, uword endaddr @ XY) -> ubyte @ Pc, ubyte @ A          ; (via 818 ($332)) save to a device
+romsub $FFDB = SETTIM(ubyte low @ A, ubyte middle @ X, ubyte high @ Y)      ; set the software clock
+romsub $FFDE = RDTIM() -> ubyte @ A, ubyte @ X, ubyte @ Y       ; read the software clock (A=lo,X=mid,Y=high)
+romsub $FFE1 = STOP() clobbers(X) -> ubyte @ Pz, ubyte @ A      ; (via 808 ($328)) check the STOP key (and some others in A)
+romsub $FFE4 = GETIN() clobbers(X,Y) -> ubyte @Pc, ubyte @ A    ; (via 810 ($32A)) get a character
+romsub $FFE7 = CLALL() clobbers(A,X)                            ; (via 812 ($32C)) close all files
+romsub $FFEA = UDTIM() clobbers(A,X)                            ; update the software clock
+romsub $FFED = SCREEN() -> ubyte @ X, ubyte @ Y                 ; read number of screen rows and columns
+romsub $FFF0 = PLOT(ubyte col @ Y, ubyte row @ X, ubyte dir @ Pc) -> ubyte @ X, ubyte @ Y       ; read/set position of cursor on screen.  Use txt.plot for a 'safe' wrapper that preserves X.
+romsub $FFF3 = IOBASE() -> uword @ XY                           ; read base address of I/O devices
+
+; ---- end of C64 compatible ROM kernal routines ----
+
+; ---- utilities -----
+
+asmsub STOP2() -> ubyte @A  {
+    ; -- check if STOP key was pressed, returns true if so.  More convenient to use than STOP() because that only sets the carry status flag.
+    %asm {{
+        txa
+        pha
+        jsr  c64.STOP
+        beq  +
+        pla
+        tax
+        lda  #0
+        rts
++       pla
+        tax
+        lda  #1
+        rts
+    }}
+}
+
+asmsub RDTIM16() -> uword @AY {
+    ; --  like RDTIM() but only returning the lower 16 bits in AY for convenience
+    %asm {{
+        stx  P8ZP_SCRATCH_REG
+        jsr  c64.RDTIM
+        pha
+        txa
+        tay
+        pla
+        ldx  P8ZP_SCRATCH_REG
+        rts
+    }}
+}
+
+
+; ---- system utility routines that are essentially the same as on the C64: -----
+asmsub  disable_runstop_and_charsetswitch() clobbers(A) {
+    %asm {{
+        lda  #$80
+        sta  247    ; disable charset switching
+        lda  #112
+        sta  808    ; disable run/stop key
+        rts
+    }}
+}
+
+asmsub  set_irq(uword handler @AY, ubyte useKernal @Pc) clobbers(A)  {
+	%asm {{
+	        sta  _modified+1
+	        sty  _modified+2
+	        lda  #0
+	        adc  #0
+	        sta  _use_kernal
+		sei
+		lda  #<_irq_handler
+		sta  c64.CINV
+		lda  #>_irq_handler
+		sta  c64.CINV+1
+		cli
+		rts
+_irq_handler    jsr  _irq_handler_init
+_modified	jsr  $ffff                      ; modified
+		jsr  _irq_handler_end
+		lda  _use_kernal
+		bne  +
+		lda  #$ff
+		sta  c64.VICIRQ			; acknowledge raster irq
+		lda  c64.CIA1ICR		; acknowledge CIA1 interrupt
+		; end irq processing - don't use kernal's irq handling
+		pla
+		tay
+		pla
+		tax
+		pla
+		rti
++		jmp  c64.IRQDFRT		; continue with normal kernal irq routine
+
+_use_kernal     .byte  0
+
+_irq_handler_init
+		; save all zp scratch registers and the X register as these might be clobbered by the irq routine
+		stx  IRQ_X_REG
+		lda  P8ZP_SCRATCH_B1
+		sta  IRQ_SCRATCH_ZPB1
+		lda  P8ZP_SCRATCH_REG
+		sta  IRQ_SCRATCH_ZPREG
+		lda  P8ZP_SCRATCH_W1
+		sta  IRQ_SCRATCH_ZPWORD1
+		lda  P8ZP_SCRATCH_W1+1
+		sta  IRQ_SCRATCH_ZPWORD1+1
+		lda  P8ZP_SCRATCH_W2
+		sta  IRQ_SCRATCH_ZPWORD2
+		lda  P8ZP_SCRATCH_W2+1
+		sta  IRQ_SCRATCH_ZPWORD2+1
+		; stack protector; make sure we don't clobber the top of the evaluation stack
+		dex
+		dex
+		dex
+		dex
+		dex
+		dex
+		cld
+		rts
+
+_irq_handler_end
+		; restore all zp scratch registers and the X register
+		lda  IRQ_SCRATCH_ZPB1
+		sta  P8ZP_SCRATCH_B1
+		lda  IRQ_SCRATCH_ZPREG
+		sta  P8ZP_SCRATCH_REG
+		lda  IRQ_SCRATCH_ZPWORD1
+		sta  P8ZP_SCRATCH_W1
+		lda  IRQ_SCRATCH_ZPWORD1+1
+		sta  P8ZP_SCRATCH_W1+1
+		lda  IRQ_SCRATCH_ZPWORD2
+		sta  P8ZP_SCRATCH_W2
+		lda  IRQ_SCRATCH_ZPWORD2+1
+		sta  P8ZP_SCRATCH_W2+1
+		ldx  IRQ_X_REG
+		rts
+
+IRQ_X_REG		.byte  0
+IRQ_SCRATCH_ZPB1	.byte  0
+IRQ_SCRATCH_ZPREG	.byte  0
+IRQ_SCRATCH_ZPWORD1	.word  0
+IRQ_SCRATCH_ZPWORD2	.word  0
+
+		}}
+}
+
+asmsub  restore_irq() clobbers(A) {
+	%asm {{
+		sei
+		lda  #<c64.IRQDFRT
+		sta  c64.CINV
+		lda  #>c64.IRQDFRT
+		sta  c64.CINV+1
+		lda  #0
+		sta  c64.IREQMASK	; disable raster irq
+		lda  #%10000001
+		sta  c64.CIA1ICR	; restore CIA1 irq
+		cli
+		rts
+	}}
+}
+
+asmsub  set_rasterirq(uword handler @AY, uword rasterpos @R0, ubyte useKernal @Pc) clobbers(A) {
+	%asm {{
+	        sta  _modified+1
+	        sty  _modified+2
+	        lda  #0
+	        adc  #0
+	        sta  set_irq._use_kernal
+		lda  cx16.r0
+		ldy  cx16.r0+1
+		sei
+		jsr  _setup_raster_irq
+		lda  #<_raster_irq_handler
+		sta  c64.CINV
+		lda  #>_raster_irq_handler
+		sta  c64.CINV+1
+		cli
+		rts
+
+_raster_irq_handler
+		jsr  set_irq._irq_handler_init
+_modified	jsr  $ffff              ; modified
+		jsr  set_irq._irq_handler_end
+                lda  #$ff
+                sta  c64.VICIRQ			; acknowledge raster irq
+		lda  set_irq._use_kernal
+		bne  +
+		; end irq processing - don't use kernal's irq handling
+		pla
+		tay
+		pla
+		tax
+		pla
+		rti
++		jmp  c64.IRQDFRT                ; continue with kernal irq routine
+
+_setup_raster_irq
+		pha
+		lda  #%01111111
+		sta  c64.CIA1ICR    ; "switch off" interrupts signals from cia-1
+		sta  c64.CIA2ICR    ; "switch off" interrupts signals from cia-2
+		and  c64.SCROLY
+		sta  c64.SCROLY     ; clear most significant bit of raster position
+		lda  c64.CIA1ICR    ; ack previous irq
+		lda  c64.CIA2ICR    ; ack previous irq
+		pla
+		sta  c64.RASTER     ; set the raster line number where interrupt should occur
+		cpy  #0
+		beq  +
+		lda  c64.SCROLY
+		ora  #%10000000
+		sta  c64.SCROLY     ; set most significant bit of raster position
++		lda  #%00000001
+		sta  c64.IREQMASK   ;enable raster interrupt signals from vic
+		rts
+	}}
+}
+
+}
+
+c128 {
+; ---- C128 specific registers ----
+
+    &ubyte  VM1     = $0A2C         ; shadow for VUC $d018 in text mode
+    &ubyte  VM2     = $0A2D         ; shadow for VIC $d018 in bitmap screen mode
+    &ubyte  VM3     = $0A2E         ; starting page for VDC screen mem
+    &ubyte  VM4     = $0A2F         ; starting page for VDC attribute mem
+
+
+; ---- C128 specific system utility routines: ----
+
+asmsub  init_system()  {
+    ; Initializes the machine to a sane starting state.
+    ; Called automatically by the loader program logic.
+    ; This means that the BASIC, KERNAL and CHARGEN ROMs are banked in,
+    ; the VIC, SID and CIA chips are reset, screen is cleared, and the default IRQ is set.
+    ; Also a different color scheme is chosen to identify ourselves a little.
+    ; Uppercase charset is activated, and all three registers set to 0, status flags cleared.
+    %asm {{
+        sei
+        cld
+        ;;lda  #%00101111                     ; TODO c128 ram and rom bank selection how?
+        ;;sta  $00
+        ;;lda  #%00100111
+        ;;sta  $01
+        jsr  c64.IOINIT
+        jsr  c64.RESTOR
+        jsr  c64.CINT
+        lda  #6
+        sta  c64.EXTCOL
+        lda  #7
+        sta  c64.COLOR
+        lda  #0
+        sta  c64.BGCOL0
+        jsr  c64.disable_runstop_and_charsetswitch
+        clc
+        clv
+        cli
+        rts
+    }}
+}
+
+asmsub  init_system_phase2()  {
+    %asm {{
+        rts     ; no phase 2 steps on the C128
+    }}
+}
+
+asmsub  disable_basic() clobbers(A) {
+    %asm {{
+        lda $0a04   ; disable BASIC shadow registers
+        and #$fe
+        sta $0a04
+
+        lda #$01    ; disable BASIC IRQ service routine
+        sta $12fd
+
+        lda #$ff    ; disable screen editor IRQ setup
+        sta $d8
+
+        lda #$b7    ; skip programmable function key check
+        sta $033c
+
+        lda #$0e    ; bank out BASIC ROM
+        sta $ff00
+        rts
+    }}
+}
+
+; ---- end of C128 specific system utility routines ----
+
+}
+
+sys {
+    ; ------- lowlevel system routines --------
+
+    const ubyte target = 128         ;  compilation target specifier.  64 = C64, 128 = C128,  16 = CommanderX16.
+
+
+    asmsub  reset_system()  {
+        ; Soft-reset the system back to initial power-on Basic prompt.
+        %asm {{
+            sei
+            ;lda  #14
+            ;sta  $01        ; bank the kernal in       TODO c128 how to do this?
+            jmp  (c64.RESET_VEC)
+        }}
+    }
+
+    sub wait(uword jiffies) {
+        ; --- wait approximately the given number of jiffies (1/60th seconds)
+        ;     note: the system irq handler has to be active for this to work as it depends on the system jiffy clock
+        repeat jiffies {
+            ubyte jiff = lsb(c64.RDTIM16())
+            while jiff==lsb(c64.RDTIM16()) {
+                ; wait until 1 jiffy has passed
+            }
+        }
+    }
+
+    asmsub waitvsync() clobbers(A) {
+        ; --- busy wait till the next vsync has occurred (approximately), without depending on custom irq handling.
+        ;     note: a more accurate way to wait for vsync is to set up a vsync irq handler instead.
+        %asm {{
+-           bit  c64.SCROLY
+            bpl  -
+-           bit  c64.SCROLY
+            bmi  -
+            rts
+        }}
+    }
+
+    inline asmsub waitrastborder() {
+        ; --- busy wait till the raster position has reached the bottom screen border (approximately)
+        ;     note: a more accurate way to do this is by using a raster irq handler instead.
+        %asm {{
+-           bit  c64.SCROLY
+            bpl  -
+        }}
+    }
+
+    asmsub memcopy(uword source @R0, uword target @R1, uword count @AY) clobbers(A,X,Y) {
+        %asm {{
+            ldx  cx16.r0
+            stx  P8ZP_SCRATCH_W1        ; source in ZP
+            ldx  cx16.r0+1
+            stx  P8ZP_SCRATCH_W1+1
+            ldx  cx16.r1
+            stx  P8ZP_SCRATCH_W2        ; target in ZP
+            ldx  cx16.r1+1
+            stx  P8ZP_SCRATCH_W2+1
+            cpy  #0
+            bne  _longcopy
+
+            ; copy <= 255 bytes
+            tay
+            bne  _copyshort
+            rts     ; nothing to copy
+
+_copyshort
+            ; decrease source and target pointers so we can simply index by Y
+            lda  P8ZP_SCRATCH_W1
+            bne  +
+            dec  P8ZP_SCRATCH_W1+1
++           dec  P8ZP_SCRATCH_W1
+            lda  P8ZP_SCRATCH_W2
+            bne  +
+            dec  P8ZP_SCRATCH_W2+1
++           dec  P8ZP_SCRATCH_W2
+
+-           lda  (P8ZP_SCRATCH_W1),y
+            sta  (P8ZP_SCRATCH_W2),y
+            dey
+            bne  -
+            rts
+
+_longcopy
+            sta  P8ZP_SCRATCH_B1        ; lsb(count) = remainder in last page
+            tya
+            tax                         ; x = num pages (1+)
+            ldy  #0
+-           lda  (P8ZP_SCRATCH_W1),y
+            sta  (P8ZP_SCRATCH_W2),y
+            iny
+            bne  -
+            inc  P8ZP_SCRATCH_W1+1
+            inc  P8ZP_SCRATCH_W2+1
+            dex
+            bne  -
+            ldy  P8ZP_SCRATCH_B1
+            bne  _copyshort
+            rts
+        }}
+    }
+
+    asmsub memset(uword mem @R0, uword numbytes @R1, ubyte value @A) clobbers(A,X,Y) {
+        %asm {{
+            ldy  cx16.r0
+            sty  P8ZP_SCRATCH_W1
+            ldy  cx16.r0+1
+            sty  P8ZP_SCRATCH_W1+1
+            ldx  cx16.r1
+            ldy  cx16.r1+1
+            jmp  prog8_lib.memset
+        }}
+    }
+
+    asmsub memsetw(uword mem @R0, uword numwords @R1, uword value @AY) clobbers(A,X,Y) {
+        %asm {{
+            ldx  cx16.r0
+            stx  P8ZP_SCRATCH_W1
+            ldx  cx16.r0+1
+            stx  P8ZP_SCRATCH_W1+1
+            ldx  cx16.r1
+            stx  P8ZP_SCRATCH_W2
+            ldx  cx16.r1+1
+            stx  P8ZP_SCRATCH_W2+1
+            jmp  prog8_lib.memsetw
+        }}
+    }
+
+    inline asmsub read_flags() -> ubyte @A {
+        %asm {{
+        php
+        pla
+        }}
+    }
+
+    inline asmsub clear_carry() {
+        %asm {{
+        clc
+        }}
+    }
+
+    inline asmsub set_carry() {
+        %asm {{
+        sec
+        }}
+    }
+
+    inline asmsub clear_irqd() {
+        %asm {{
+        cli
+        }}
+    }
+
+    inline asmsub set_irqd() {
+        %asm {{
+        sei
+        }}
+    }
+
+    inline asmsub exit(ubyte returnvalue @A) {
+        ; -- immediately exit the program with a return code in the A register
+        %asm {{
+            jsr  c64.CLRCHN		; reset i/o channels
+            ldx  prog8_lib.orig_stackpointer
+            txs
+            rts		; return to original caller
+        }}
+    }
+
+    inline asmsub progend() -> uword @AY {
+        %asm {{
+            lda  #<prog8_program_end
+            ldy  #>prog8_program_end
+        }}
+    }
+
+}
+
+cx16 {
+
+    ; the sixteen virtual 16-bit registers that the CX16 has defined in the zeropage
+    ; they are simulated on the C128 as well but their location in memory is different
+    ; (because there's no room for them in the zeropage)
+    ; $1300-$1bff is unused RAM on C128. We'll use $1a00-$1bff as the lo/hi evalstack.
+    ; the virtual registers are allocated at the bottom of the eval-stack (should be ample space unless
+    ; you're doing insane nesting of expressions...)
+    &uword r0  = $1b00
+    &uword r1  = $1b02
+    &uword r2  = $1b04
+    &uword r3  = $1b06
+    &uword r4  = $1b08
+    &uword r5  = $1b0a
+    &uword r6  = $1b0c
+    &uword r7  = $1b0e
+    &uword r8  = $1b10
+    &uword r9  = $1b12
+    &uword r10 = $1b14
+    &uword r11 = $1b16
+    &uword r12 = $1b18
+    &uword r13 = $1b1a
+    &uword r14 = $1b1c
+    &uword r15 = $1b1e
+
+    &word r0s  = $1b00
+    &word r1s  = $1b02
+    &word r2s  = $1b04
+    &word r3s  = $1b06
+    &word r4s  = $1b08
+    &word r5s  = $1b0a
+    &word r6s  = $1b0c
+    &word r7s  = $1b0e
+    &word r8s  = $1b10
+    &word r9s  = $1b12
+    &word r10s = $1b14
+    &word r11s = $1b16
+    &word r12s = $1b18
+    &word r13s = $1b1a
+    &word r14s = $1b1c
+    &word r15s = $1b1e
+
+    &ubyte r0L  = $1b00
+    &ubyte r1L  = $1b02
+    &ubyte r2L  = $1b04
+    &ubyte r3L  = $1b06
+    &ubyte r4L  = $1b08
+    &ubyte r5L  = $1b0a
+    &ubyte r6L  = $1b0c
+    &ubyte r7L  = $1b0e
+    &ubyte r8L  = $1b10
+    &ubyte r9L  = $1b12
+    &ubyte r10L = $1b14
+    &ubyte r11L = $1b16
+    &ubyte r12L = $1b18
+    &ubyte r13L = $1b1a
+    &ubyte r14L = $1b1c
+    &ubyte r15L = $1b1e
+
+    &ubyte r0H  = $1b01
+    &ubyte r1H  = $1b03
+    &ubyte r2H  = $1b05
+    &ubyte r3H  = $1b07
+    &ubyte r4H  = $1b09
+    &ubyte r5H  = $1b0b
+    &ubyte r6H  = $1b0d
+    &ubyte r7H  = $1b0f
+    &ubyte r8H  = $1b11
+    &ubyte r9H  = $1b13
+    &ubyte r10H = $1b15
+    &ubyte r11H = $1b17
+    &ubyte r12H = $1b19
+    &ubyte r13H = $1b1b
+    &ubyte r14H = $1b1d
+    &ubyte r15H = $1b1f
+
+    &byte r0sL  = $1b00
+    &byte r1sL  = $1b02
+    &byte r2sL  = $1b04
+    &byte r3sL  = $1b06
+    &byte r4sL  = $1b08
+    &byte r5sL  = $1b0a
+    &byte r6sL  = $1b0c
+    &byte r7sL  = $1b0e
+    &byte r8sL  = $1b10
+    &byte r9sL  = $1b12
+    &byte r10sL = $1b14
+    &byte r11sL = $1b16
+    &byte r12sL = $1b18
+    &byte r13sL = $1b1a
+    &byte r14sL = $1b1c
+    &byte r15sL = $1b1e
+
+    &byte r0sH  = $1b01
+    &byte r1sH  = $1b03
+    &byte r2sH  = $1b05
+    &byte r3sH  = $1b07
+    &byte r4sH  = $1b09
+    &byte r5sH  = $1b0b
+    &byte r6sH  = $1b0d
+    &byte r7sH  = $1b0f
+    &byte r8sH  = $1b11
+    &byte r9sH  = $1b13
+    &byte r10sH = $1b15
+    &byte r11sH = $1b17
+    &byte r12sH = $1b19
+    &byte r13sH = $1b1b
+    &byte r14sH = $1b1d
+    &byte r15sH = $1b1f
+}

compiler/res/prog8lib/c128/textio.p8

@@ -0,0 +1,619 @@
+; Prog8 definitions for the Text I/O and Screen routines for the Commodore-64
+;
+; Written by Irmen de Jong (irmen@razorvine.net) - license: GNU GPL 3.0
+;
+; indent format: TABS, size=8
+
+%import syslib
+%import conv
+
+
+txt {
+
+const ubyte DEFAULT_WIDTH = 40
+const ubyte DEFAULT_HEIGHT = 25
+
+
+sub  clear_screen() {
+    txt.chrout(147)
+}
+
+sub home() {
+    txt.chrout(19)
+}
+
+sub nl() {
+    txt.chrout('\n')
+}
+
+sub spc() {
+    txt.chrout(' ')
+}
+
+asmsub column(ubyte col @A) clobbers(A, X, Y) {
+    ; ---- set the cursor on the given column (starting with 0) on the current line
+    %asm {{
+        sec
+        jsr  c64.PLOT
+        tay
+        clc
+        jmp  c64.PLOT
+    }}
+}
+
+asmsub  fill_screen (ubyte char @ A, ubyte color @ Y) clobbers(A)  {
+	; ---- fill the character screen with the given fill character and character color.
+	;      (assumes screen and color matrix are at their default addresses)
+
+	%asm {{
+		pha
+		tya
+		jsr  clear_screencolors
+		pla
+		jsr  clear_screenchars
+		rts
+        }}
+
+}
+
+asmsub  clear_screenchars (ubyte char @ A) clobbers(Y)  {
+	; ---- clear the character screen with the given fill character (leaves colors)
+	;      (assumes screen matrix is at the default address)
+	%asm {{
+		ldy  #250
+-		sta  c64.Screen+250*0-1,y
+		sta  c64.Screen+250*1-1,y
+		sta  c64.Screen+250*2-1,y
+		sta  c64.Screen+250*3-1,y
+		dey
+		bne  -
+		rts
+        }}
+}
+
+asmsub  clear_screencolors (ubyte color @ A) clobbers(Y)  {
+	; ---- clear the character screen colors with the given color (leaves characters).
+	;      (assumes color matrix is at the default address)
+	%asm {{
+		ldy  #250
+-		sta  c64.Colors+250*0-1,y
+		sta  c64.Colors+250*1-1,y
+		sta  c64.Colors+250*2-1,y
+		sta  c64.Colors+250*3-1,y
+		dey
+		bne  -
+		rts
+        }}
+}
+
+sub color (ubyte txtcol) {
+    c64.COLOR = txtcol
+}
+
+sub lowercase() {
+    c64.VMCSB |= 2
+    c128.VM1 |= 2
+}
+
+sub uppercase() {
+    c64.VMCSB &= ~2
+    c128.VM1 &= ~2
+}
+
+asmsub  scroll_left  (ubyte alsocolors @ Pc) clobbers(A, Y)  {
+	; ---- scroll the whole screen 1 character to the left
+	;      contents of the rightmost column are unchanged, you should clear/refill this yourself
+	;      Carry flag determines if screen color data must be scrolled too
+
+	%asm {{
+		stx  P8ZP_SCRATCH_REG
+		bcc _scroll_screen
+
++               ; scroll the screen and the color memory
+		ldx  #0
+		ldy  #38
+-
+        .for row=0, row<=24, row+=1
+            lda  c64.Screen + 40*row + 1,x
+            sta  c64.Screen + 40*row + 0,x
+            lda  c64.Colors + 40*row + 1,x
+            sta  c64.Colors + 40*row + 0,x
+        .next
+		inx
+		dey
+		bpl  -
+		rts
+
+_scroll_screen  ; scroll only the screen memory
+		ldx  #0
+		ldy  #38
+-
+        .for row=0, row<=24, row+=1
+            lda  c64.Screen + 40*row + 1,x
+            sta  c64.Screen + 40*row + 0,x
+        .next
+		inx
+		dey
+		bpl  -
+
+		ldx  P8ZP_SCRATCH_REG
+		rts
+	}}
+}
+
+asmsub  scroll_right  (ubyte alsocolors @ Pc) clobbers(A)  {
+	; ---- scroll the whole screen 1 character to the right
+	;      contents of the leftmost column are unchanged, you should clear/refill this yourself
+	;      Carry flag determines if screen color data must be scrolled too
+	%asm {{
+		stx  P8ZP_SCRATCH_REG
+		bcc  _scroll_screen
+
++               ; scroll the screen and the color memory
+		ldx  #38
+-
+        .for row=0, row<=24, row+=1
+            lda  c64.Screen + 40*row + 0,x
+            sta  c64.Screen + 40*row + 1,x
+            lda  c64.Colors + 40*row + 0,x
+            sta  c64.Colors + 40*row + 1,x
+        .next
+		dex
+		bpl  -
+		rts
+
+_scroll_screen  ; scroll only the screen memory
+		ldx  #38
+-
+        .for row=0, row<=24, row+=1
+            lda  c64.Screen + 40*row + 0,x
+            sta  c64.Screen + 40*row + 1,x
+        .next
+		dex
+		bpl  -
+
+		ldx  P8ZP_SCRATCH_REG
+		rts
+	}}
+}
+
+asmsub  scroll_up  (ubyte alsocolors @ Pc) clobbers(A)  {
+	; ---- scroll the whole screen 1 character up
+	;      contents of the bottom row are unchanged, you should refill/clear this yourself
+	;      Carry flag determines if screen color data must be scrolled too
+	%asm {{
+		stx  P8ZP_SCRATCH_REG
+		bcc  _scroll_screen
+
++               ; scroll the screen and the color memory
+		ldx #39
+-
+        .for row=1, row<=24, row+=1
+            lda  c64.Screen + 40*row,x
+            sta  c64.Screen + 40*(row-1),x
+            lda  c64.Colors + 40*row,x
+            sta  c64.Colors + 40*(row-1),x
+        .next
+		dex
+		bpl  -
+		rts
+
+_scroll_screen  ; scroll only the screen memory
+		ldx #39
+-
+        .for row=1, row<=24, row+=1
+            lda  c64.Screen + 40*row,x
+            sta  c64.Screen + 40*(row-1),x
+        .next
+		dex
+		bpl  -
+
+		ldx  P8ZP_SCRATCH_REG
+		rts
+	}}
+}
+
+asmsub  scroll_down  (ubyte alsocolors @ Pc) clobbers(A)  {
+	; ---- scroll the whole screen 1 character down
+	;      contents of the top row are unchanged, you should refill/clear this yourself
+	;      Carry flag determines if screen color data must be scrolled too
+	%asm {{
+		stx  P8ZP_SCRATCH_REG
+		bcc  _scroll_screen
+
++               ; scroll the screen and the color memory
+		ldx #39
+-
+        .for row=23, row>=0, row-=1
+            lda  c64.Colors + 40*row,x
+            sta  c64.Colors + 40*(row+1),x
+            lda  c64.Screen + 40*row,x
+            sta  c64.Screen + 40*(row+1),x
+        .next
+		dex
+		bpl  -
+		rts
+
+_scroll_screen  ; scroll only the screen memory
+		ldx #39
+-
+        .for row=23, row>=0, row-=1
+            lda  c64.Screen + 40*row,x
+            sta  c64.Screen + 40*(row+1),x
+        .next
+		dex
+		bpl  -
+
+		ldx  P8ZP_SCRATCH_REG
+		rts
+	}}
+}
+
+romsub $FFD2 = chrout(ubyte char @ A)    ; for consistency. You can also use c64.CHROUT directly ofcourse.
+
+asmsub  print (str text @ AY) clobbers(A,Y)  {
+	; ---- print null terminated string from A/Y
+	; note: the compiler contains an optimization that will replace
+	;       a call to this subroutine with a string argument of just one char,
+	;       by just one call to c64.CHROUT of that single char.
+	%asm {{
+		sta  P8ZP_SCRATCH_B1
+		sty  P8ZP_SCRATCH_REG
+		ldy  #0
+-		lda  (P8ZP_SCRATCH_B1),y
+		beq  +
+		jsr  c64.CHROUT
+		iny
+		bne  -
++		rts
+	}}
+}
+
+asmsub  print_ub0  (ubyte value @ A) clobbers(A,Y)  {
+	; ---- print the ubyte in A in decimal form, with left padding 0s (3 positions total)
+	%asm {{
+		stx  P8ZP_SCRATCH_REG
+		jsr  conv.ubyte2decimal
+		pha
+		tya
+		jsr  c64.CHROUT
+		pla
+		jsr  c64.CHROUT
+		txa
+		jsr  c64.CHROUT
+		ldx  P8ZP_SCRATCH_REG
+		rts
+	}}
+}
+
+asmsub  print_ub  (ubyte value @ A) clobbers(A,Y)  {
+	; ---- print the ubyte in A in decimal form, without left padding 0s
+	%asm {{
+		stx  P8ZP_SCRATCH_REG
+		jsr  conv.ubyte2decimal
+_print_byte_digits
+		pha
+		cpy  #'0'
+		beq  +
+		tya
+		jsr  c64.CHROUT
+		pla
+		jsr  c64.CHROUT
+		jmp  _ones
++       pla
+        cmp  #'0'
+        beq  _ones
+        jsr  c64.CHROUT
+_ones   txa
+		jsr  c64.CHROUT
+		ldx  P8ZP_SCRATCH_REG
+		rts
+	}}
+}
+
+asmsub  print_b  (byte value @ A) clobbers(A,Y)  {
+	; ---- print the byte in A in decimal form, without left padding 0s
+	%asm {{
+		stx  P8ZP_SCRATCH_REG
+		pha
+		cmp  #0
+		bpl  +
+		lda  #'-'
+		jsr  c64.CHROUT
++		pla
+		jsr  conv.byte2decimal
+		jmp  print_ub._print_byte_digits
+	}}
+}
+
+asmsub  print_ubhex  (ubyte value @ A, ubyte prefix @ Pc) clobbers(A,Y)  {
+	; ---- print the ubyte in A in hex form (if Carry is set, a radix prefix '$' is printed as well)
+	%asm {{
+		stx  P8ZP_SCRATCH_REG
+		bcc  +
+		pha
+		lda  #'$'
+		jsr  c64.CHROUT
+		pla
++		jsr  conv.ubyte2hex
+		jsr  c64.CHROUT
+		tya
+		jsr  c64.CHROUT
+		ldx  P8ZP_SCRATCH_REG
+		rts
+	}}
+}
+
+asmsub  print_ubbin  (ubyte value @ A, ubyte prefix @ Pc) clobbers(A,Y)  {
+	; ---- print the ubyte in A in binary form (if Carry is set, a radix prefix '%' is printed as well)
+	%asm {{
+		stx  P8ZP_SCRATCH_REG
+		sta  P8ZP_SCRATCH_B1
+		bcc  +
+		lda  #'%'
+		jsr  c64.CHROUT
++		ldy  #8
+-		lda  #'0'
+		asl  P8ZP_SCRATCH_B1
+		bcc  +
+		lda  #'1'
++		jsr  c64.CHROUT
+		dey
+		bne  -
+		ldx  P8ZP_SCRATCH_REG
+		rts
+	}}
+}
+
+asmsub  print_uwbin  (uword value @ AY, ubyte prefix @ Pc) clobbers(A,Y)  {
+	; ---- print the uword in A/Y in binary form (if Carry is set, a radix prefix '%' is printed as well)
+	%asm {{
+		pha
+		tya
+		jsr  print_ubbin
+		pla
+		clc
+		jmp  print_ubbin
+	}}
+}
+
+asmsub  print_uwhex  (uword value @ AY, ubyte prefix @ Pc) clobbers(A,Y)  {
+	; ---- print the uword in A/Y in hexadecimal form (4 digits)
+	;      (if Carry is set, a radix prefix '$' is printed as well)
+	%asm {{
+		pha
+		tya
+		jsr  print_ubhex
+		pla
+		clc
+		jmp  print_ubhex
+	}}
+}
+
+asmsub  print_uw0  (uword value @ AY) clobbers(A,Y)  {
+	; ---- print the uword in A/Y in decimal form, with left padding 0s (5 positions total)
+	%asm {{
+	    stx  P8ZP_SCRATCH_REG
+		jsr  conv.uword2decimal
+		ldy  #0
+-		lda  conv.uword2decimal.decTenThousands,y
+        beq  +
+		jsr  c64.CHROUT
+		iny
+		bne  -
++		ldx  P8ZP_SCRATCH_REG
+		rts
+	}}
+}
+
+asmsub  print_uw  (uword value @ AY) clobbers(A,Y)  {
+	; ---- print the uword in A/Y in decimal form, without left padding 0s
+	%asm {{
+	    stx  P8ZP_SCRATCH_REG
+		jsr  conv.uword2decimal
+		ldx  P8ZP_SCRATCH_REG
+		ldy  #0
+-		lda  conv.uword2decimal.decTenThousands,y
+		beq  _allzero
+		cmp  #'0'
+		bne  _gotdigit
+		iny
+		bne  -
+
+_gotdigit
+		jsr  c64.CHROUT
+		iny
+		lda  conv.uword2decimal.decTenThousands,y
+		bne  _gotdigit
+		rts
+_allzero
+        lda  #'0'
+        jmp  c64.CHROUT
+	}}
+}
+
+asmsub  print_w  (word value @ AY) clobbers(A,Y)  {
+	; ---- print the (signed) word in A/Y in decimal form, without left padding 0's
+	%asm {{
+		cpy  #0
+		bpl  +
+		pha
+		lda  #'-'
+		jsr  c64.CHROUT
+		tya
+		eor  #255
+		tay
+		pla
+		eor  #255
+		clc
+		adc  #1
+		bcc  +
+		iny
++		jmp  print_uw
+	}}
+}
+
+asmsub  input_chars  (uword buffer @ AY) clobbers(A) -> ubyte @ Y  {
+	; ---- Input a string (max. 80 chars) from the keyboard. Returns length in Y. (string is terminated with a 0 byte as well)
+	;      It assumes the keyboard is selected as I/O channel!
+
+	%asm {{
+		sta  P8ZP_SCRATCH_W1
+		sty  P8ZP_SCRATCH_W1+1
+		ldy  #0				; char counter = 0
+-		jsr  c64.CHRIN
+		cmp  #$0d			; return (ascii 13) pressed?
+		beq  +				; yes, end.
+		sta  (P8ZP_SCRATCH_W1),y	; else store char in buffer
+		iny
+		bne  -
++		lda  #0
+		sta  (P8ZP_SCRATCH_W1),y	; finish string with 0 byte
+		rts
+
+	}}
+}
+
+asmsub  setchr  (ubyte col @X, ubyte row @Y, ubyte character @A) clobbers(A, Y)  {
+	; ---- sets the character in the screen matrix at the given position
+	%asm {{
+		pha
+		tya
+		asl  a
+		tay
+		lda  _screenrows+1,y
+		sta  _mod+2
+		txa
+		clc
+		adc  _screenrows,y
+		sta  _mod+1
+		bcc  +
+		inc  _mod+2
++		pla
+_mod		sta  $ffff		; modified
+		rts
+
+_screenrows	.word  $0400 + range(0, 1000, 40)
+	}}
+}
+
+asmsub  getchr  (ubyte col @A, ubyte row @Y) clobbers(Y) -> ubyte @ A {
+	; ---- get the character in the screen matrix at the given location
+	%asm  {{
+		pha
+		tya
+		asl  a
+		tay
+		lda  setchr._screenrows+1,y
+		sta  _mod+2
+		pla
+		clc
+		adc  setchr._screenrows,y
+		sta  _mod+1
+		bcc  _mod
+		inc  _mod+2
+_mod		lda  $ffff		; modified
+		rts
+	}}
+}
+
+asmsub  setclr  (ubyte col @X, ubyte row @Y, ubyte color @A) clobbers(A, Y)  {
+	; ---- set the color in A on the screen matrix at the given position
+	%asm {{
+		pha
+		tya
+		asl  a
+		tay
+		lda  _colorrows+1,y
+		sta  _mod+2
+		txa
+		clc
+		adc  _colorrows,y
+		sta  _mod+1
+		bcc  +
+		inc  _mod+2
++		pla
+_mod		sta  $ffff		; modified
+		rts
+
+_colorrows	.word  $d800 + range(0, 1000, 40)
+	}}
+}
+
+asmsub  getclr  (ubyte col @A, ubyte row @Y) clobbers(Y) -> ubyte @ A {
+	; ---- get the color in the screen color matrix at the given location
+	%asm  {{
+		pha
+		tya
+		asl  a
+		tay
+		lda  setclr._colorrows+1,y
+		sta  _mod+2
+		pla
+		clc
+		adc  setclr._colorrows,y
+		sta  _mod+1
+		bcc  _mod
+		inc  _mod+2
+_mod		lda  $ffff		; modified
+		rts
+	}}
+}
+
+sub  setcc  (ubyte column, ubyte row, ubyte char, ubyte charcolor)  {
+	; ---- set char+color at the given position on the screen
+	%asm {{
+		lda  row
+		asl  a
+		tay
+		lda  setchr._screenrows+1,y
+		sta  _charmod+2
+		adc  #$d4
+		sta  _colormod+2
+		lda  setchr._screenrows,y
+		clc
+		adc  column
+		sta  _charmod+1
+		sta  _colormod+1
+		bcc  +
+		inc  _charmod+2
+		inc  _colormod+2
++		lda  char
+_charmod	sta  $ffff		; modified
+		lda  charcolor
+_colormod	sta  $ffff		; modified
+		rts
+	}}
+}
+
+asmsub  plot  (ubyte col @ Y, ubyte row @ A) clobbers(A) {
+	; ---- safe wrapper around PLOT kernal routine, to save the X register.
+	%asm  {{
+		stx  P8ZP_SCRATCH_REG
+		tax
+		clc
+		jsr  c64.PLOT
+		ldx  P8ZP_SCRATCH_REG
+		rts
+	}}
+}
+
+asmsub width() clobbers(X,Y) -> ubyte @A {
+    ; -- returns the text screen width (number of columns)
+    %asm {{
+        jsr  c64.SCREEN
+        txa
+        rts
+    }}
+}
+
+asmsub height() clobbers(X, Y) -> ubyte @A {
+    ; -- returns the text screen height (number of rows)
+    %asm {{
+        jsr  c64.SCREEN
+        tya
+        rts
+    }}
+}
+
+}

compiler/res/prog8lib/c64/floats.asm

@@ -0,0 +1,741 @@
+; --- low level floating point assembly routines for the C64
+
+FL_ONE_const	.byte  129     			; 1.0
+FL_ZERO_const	.byte  0,0,0,0,0		; 0.0
+FL_LOG2_const	.byte  $80, $31, $72, $17, $f8	; log(2)
+
+
+floats_store_reg	.byte  0		; temp storage
+
+
+ub2float	.proc
+		; -- convert ubyte in SCRATCH_ZPB1 to float at address A/Y
+		;    clobbers A, Y
+		stx  P8ZP_SCRATCH_REG
+		sta  P8ZP_SCRATCH_W2
+		sty  P8ZP_SCRATCH_W2+1
+		ldy  P8ZP_SCRATCH_B1
+		lda  #0
+		jsr  GIVAYF
+_fac_to_mem	ldx  P8ZP_SCRATCH_W2
+		ldy  P8ZP_SCRATCH_W2+1
+		jsr  MOVMF
+		ldx  P8ZP_SCRATCH_REG
+		rts
+		.pend
+
+b2float		.proc
+		; -- convert byte in SCRATCH_ZPB1 to float at address A/Y
+		;    clobbers A, Y
+		stx  P8ZP_SCRATCH_REG
+		sta  P8ZP_SCRATCH_W2
+		sty  P8ZP_SCRATCH_W2+1
+		lda  P8ZP_SCRATCH_B1
+		jsr  FREADSA
+		jmp  ub2float._fac_to_mem
+		.pend
+
+uw2float	.proc
+		; -- convert uword in SCRATCH_ZPWORD1 to float at address A/Y
+		stx  P8ZP_SCRATCH_REG
+		sta  P8ZP_SCRATCH_W2
+		sty  P8ZP_SCRATCH_W2+1
+		lda  P8ZP_SCRATCH_W1
+		ldy  P8ZP_SCRATCH_W1+1
+		jsr  GIVUAYFAY
+		jmp  ub2float._fac_to_mem
+		.pend
+
+w2float		.proc
+		; -- convert word in SCRATCH_ZPWORD1 to float at address A/Y
+		stx  P8ZP_SCRATCH_REG
+		sta  P8ZP_SCRATCH_W2
+		sty  P8ZP_SCRATCH_W2+1
+		ldy  P8ZP_SCRATCH_W1
+		lda  P8ZP_SCRATCH_W1+1
+		jsr  GIVAYF
+		jmp  ub2float._fac_to_mem
+		.pend
+
+
+cast_from_uw	.proc
+		; -- uword in A/Y into float var at (P8ZP_SCRATCH_W2)
+		stx  P8ZP_SCRATCH_REG
+		jsr  GIVUAYFAY
+		jmp  ub2float._fac_to_mem
+		.pend
+
+
+cast_from_w	.proc
+		; -- word in A/Y into float var at (P8ZP_SCRATCH_W2)
+		stx  P8ZP_SCRATCH_REG
+		jsr  GIVAYFAY
+		jmp  ub2float._fac_to_mem
+		.pend
+
+
+cast_from_ub	.proc
+		; -- ubyte in Y into float var at (P8ZP_SCRATCH_W2)
+		stx  P8ZP_SCRATCH_REG
+		jsr  FREADUY
+		jmp  ub2float._fac_to_mem
+		.pend
+
+
+cast_from_b	.proc
+		; -- byte in A into float var at (P8ZP_SCRATCH_W2)
+		stx  P8ZP_SCRATCH_REG
+		jsr  FREADSA
+		jmp  ub2float._fac_to_mem
+		.pend
+
+cast_as_uw_into_ya	.proc               ; also used for float 2 ub
+		; -- cast float at A/Y to uword into Y/A
+		jsr  MOVFM
+		jmp  cast_FAC1_as_uw_into_ya
+		.pend
+
+cast_as_w_into_ay	.proc               ; also used for float 2 b
+		; -- cast float at A/Y to word into A/Y
+		jsr  MOVFM
+		jmp  cast_FAC1_as_w_into_ay
+		.pend
+
+cast_FAC1_as_uw_into_ya	.proc               ; also used for float 2 ub
+		; -- cast fac1 to uword into Y/A
+		stx  P8ZP_SCRATCH_REG
+		jsr  GETADR     ; into Y/A
+		ldx  P8ZP_SCRATCH_REG
+		rts
+		.pend
+
+cast_FAC1_as_w_into_ay	.proc               ; also used for float 2 b
+		; -- cast fac1 to word into A/Y
+		stx  P8ZP_SCRATCH_REG
+		jsr  AYINT
+		ldy  $64
+		lda  $65
+		ldx  P8ZP_SCRATCH_REG
+		rts
+		.pend
+
+
+stack_b2float	.proc
+		; -- b2float operating on the stack
+		inx
+		lda  P8ESTACK_LO,x
+		stx  P8ZP_SCRATCH_REG
+		jsr  FREADSA
+		jmp  push_fac1._internal
+		.pend
+
+stack_w2float	.proc
+		; -- w2float operating on the stack
+		inx
+		ldy  P8ESTACK_LO,x
+		lda  P8ESTACK_HI,x
+		stx  P8ZP_SCRATCH_REG
+		jsr  GIVAYF
+		jmp  push_fac1._internal
+		.pend
+
+stack_ub2float	.proc
+		; -- ub2float operating on the stack
+		inx
+		lda  P8ESTACK_LO,x
+		stx  P8ZP_SCRATCH_REG
+		tay
+		lda  #0
+		jsr  GIVAYF
+		jmp  push_fac1._internal
+		.pend
+
+stack_uw2float	.proc
+		; -- uw2float operating on the stack
+		inx
+		lda  P8ESTACK_LO,x
+		ldy  P8ESTACK_HI,x
+		stx  P8ZP_SCRATCH_REG
+		jsr  GIVUAYFAY
+		jmp  push_fac1._internal
+		.pend
+
+stack_float2w	.proc               ; also used for float2b
+		jsr  pop_float_fac1
+		stx  P8ZP_SCRATCH_REG
+		jsr  AYINT
+		ldx  P8ZP_SCRATCH_REG
+		lda  $64
+		sta  P8ESTACK_HI,x
+		lda  $65
+		sta  P8ESTACK_LO,x
+		dex
+		rts
+		.pend
+
+stack_float2uw	.proc               ; also used for float2ub
+		jsr  pop_float_fac1
+		stx  P8ZP_SCRATCH_REG
+		jsr  GETADR
+		ldx  P8ZP_SCRATCH_REG
+		sta  P8ESTACK_HI,x
+		tya
+		sta  P8ESTACK_LO,x
+		dex
+		rts
+		.pend
+
+push_float	.proc
+		; ---- push mflpt5 in A/Y onto stack
+		; (taking 3 stack positions = 6 bytes of which 1 is padding)
+		sta  P8ZP_SCRATCH_W1
+		sty  P8ZP_SCRATCH_W1+1
+		ldy  #0
+		lda  (P8ZP_SCRATCH_W1),y
+		sta  P8ESTACK_LO,x
+		iny
+		lda  (P8ZP_SCRATCH_W1),y
+		sta  P8ESTACK_HI,x
+		dex
+		iny
+		lda  (P8ZP_SCRATCH_W1),y
+		sta  P8ESTACK_LO,x
+		iny
+		lda  (P8ZP_SCRATCH_W1),y
+		sta  P8ESTACK_HI,x
+		dex
+		iny
+		lda  (P8ZP_SCRATCH_W1),y
+		sta  P8ESTACK_LO,x
+		dex
+		rts
+		.pend
+
+pop_float	.proc
+		; ---- pops mflpt5 from stack to memory A/Y
+		; (frees 3 stack positions = 6 bytes of which 1 is padding)
+		sta  P8ZP_SCRATCH_W1
+		sty  P8ZP_SCRATCH_W1+1
+		ldy  #4
+		inx
+		lda  P8ESTACK_LO,x
+		sta  (P8ZP_SCRATCH_W1),y
+		dey
+		inx
+		lda  P8ESTACK_HI,x
+		sta  (P8ZP_SCRATCH_W1),y
+		dey
+		lda  P8ESTACK_LO,x
+		sta  (P8ZP_SCRATCH_W1),y
+		dey
+		inx
+		lda  P8ESTACK_HI,x
+		sta  (P8ZP_SCRATCH_W1),y
+		dey
+		lda  P8ESTACK_LO,x
+		sta  (P8ZP_SCRATCH_W1),y
+		rts
+		.pend
+
+pop_float_fac1	.proc
+		; -- pops float from stack into FAC1
+		lda  #<fmath_float1
+		ldy  #>fmath_float1
+		jsr  pop_float
+		lda  #<fmath_float1
+		ldy  #>fmath_float1
+		jmp  MOVFM
+		.pend
+
+copy_float	.proc
+		; -- copies the 5 bytes of the mflt value pointed to by P8ZP_SCRATCH_W1,
+		;    into the 5 bytes pointed to by A/Y.  Clobbers A,Y.
+		sta  P8ZP_SCRATCH_W2
+		sty  P8ZP_SCRATCH_W2+1
+		ldy  #0
+		lda  (P8ZP_SCRATCH_W1),y
+		sta  (P8ZP_SCRATCH_W2),y
+		iny
+		lda  (P8ZP_SCRATCH_W1),y
+		sta  (P8ZP_SCRATCH_W2),y
+		iny
+		lda  (P8ZP_SCRATCH_W1),y
+		sta  (P8ZP_SCRATCH_W2),y
+		iny
+		lda  (P8ZP_SCRATCH_W1),y
+		sta  (P8ZP_SCRATCH_W2),y
+		iny
+		lda  (P8ZP_SCRATCH_W1),y
+		sta  (P8ZP_SCRATCH_W2),y
+		rts
+		.pend
+
+inc_var_f	.proc
+		; -- add 1 to float pointed to by A/Y
+		sta  P8ZP_SCRATCH_W1
+		sty  P8ZP_SCRATCH_W1+1
+		stx  P8ZP_SCRATCH_REG
+		jsr  MOVFM
+		lda  #<FL_ONE_const
+		ldy  #>FL_ONE_const
+		jsr  FADD
+		ldx  P8ZP_SCRATCH_W1
+		ldy  P8ZP_SCRATCH_W1+1
+		jsr  MOVMF
+		ldx  P8ZP_SCRATCH_REG
+		rts
+		.pend
+
+dec_var_f	.proc
+		; -- subtract 1 from float pointed to by A/Y
+		sta  P8ZP_SCRATCH_W1
+		sty  P8ZP_SCRATCH_W1+1
+		stx  P8ZP_SCRATCH_REG
+		lda  #<FL_ONE_const
+		ldy  #>FL_ONE_const
+		jsr  MOVFM
+		lda  P8ZP_SCRATCH_W1
+		ldy  P8ZP_SCRATCH_W1+1
+		jsr  FSUB
+		ldx  P8ZP_SCRATCH_W1
+		ldy  P8ZP_SCRATCH_W1+1
+		jsr  MOVMF
+		ldx  P8ZP_SCRATCH_REG
+		rts
+		.pend
+
+
+pop_2_floats_f2_in_fac1	.proc
+		; -- pop 2 floats from stack, load the second one in FAC1 as well
+		lda  #<fmath_float2
+		ldy  #>fmath_float2
+		jsr  pop_float
+		lda  #<fmath_float1
+		ldy  #>fmath_float1
+		jsr  pop_float
+		lda  #<fmath_float2
+		ldy  #>fmath_float2
+		jmp  MOVFM
+		.pend
+
+
+fmath_float1	.byte 0,0,0,0,0	; storage for a mflpt5 value
+fmath_float2	.byte 0,0,0,0,0	; storage for a mflpt5 value
+
+
+push_fac1	.proc
+		; -- push the float in FAC1 onto the stack
+		stx  P8ZP_SCRATCH_REG
+_internal	ldx  #<fmath_float1
+		ldy  #>fmath_float1
+		jsr  MOVMF
+		lda  #<fmath_float1
+		ldy  #>fmath_float1
+		ldx  P8ZP_SCRATCH_REG
+		jmp  push_float
+		.pend
+
+
+pow_f		.proc
+		; -- push f1 ** f2 on stack
+		lda  #<fmath_float2
+		ldy  #>fmath_float2
+		jsr  pop_float
+		lda  #<fmath_float1
+		ldy  #>fmath_float1
+		jsr  pop_float
+		stx  P8ZP_SCRATCH_REG
+		lda  #<fmath_float1
+		ldy  #>fmath_float1
+		jsr  CONUPK		; fac2 = float1
+		lda  #<fmath_float2
+		ldy  #>fmath_float2
+		jsr  FPWR
+		jmp  push_fac1._internal
+		.pend
+
+div_f		.proc
+		; -- push f1/f2 on stack
+		jsr  pop_2_floats_f2_in_fac1
+		stx  P8ZP_SCRATCH_REG
+		lda  #<fmath_float1
+		ldy  #>fmath_float1
+		jsr  FDIV
+		jmp  push_fac1._internal
+		.pend
+
+add_f		.proc
+		; -- push f1+f2 on stack
+		jsr  pop_2_floats_f2_in_fac1
+		stx  P8ZP_SCRATCH_REG
+		lda  #<fmath_float1
+		ldy  #>fmath_float1
+		jsr  FADD
+		jmp  push_fac1._internal
+		.pend
+
+sub_f		.proc
+		; -- push f1-f2 on stack
+		jsr  pop_2_floats_f2_in_fac1
+		stx  P8ZP_SCRATCH_REG
+		lda  #<fmath_float1
+		ldy  #>fmath_float1
+		jsr  FSUB
+		jmp  push_fac1._internal
+		.pend
+
+mul_f		.proc
+		; -- push f1*f2 on stack
+		jsr  pop_2_floats_f2_in_fac1
+		stx  P8ZP_SCRATCH_REG
+		lda  #<fmath_float1
+		ldy  #>fmath_float1
+		jsr  FMULT
+		jmp  push_fac1._internal
+		.pend
+
+neg_f		.proc
+		; -- toggle the sign bit on the stack
+		lda  P8ESTACK_HI+3,x
+		eor  #$80
+		sta  P8ESTACK_HI+3,x
+		rts
+		.pend
+
+var_fac1_less_f	.proc
+		; -- is the float in FAC1 < the variable AY?
+		stx  P8ZP_SCRATCH_REG
+		jsr  FCOMP
+		ldx  P8ZP_SCRATCH_REG
+		cmp  #255
+		beq  +
+		lda  #0
+		rts
++		lda  #1
+		rts
+		.pend
+
+var_fac1_lesseq_f	.proc
+		; -- is the float in FAC1 <= the variable AY?
+		stx  P8ZP_SCRATCH_REG
+		jsr  FCOMP
+		ldx  P8ZP_SCRATCH_REG
+		cmp  #0
+		beq  +
+		cmp  #255
+		beq  +
+		lda  #0
+		rts
++		lda  #1
+		rts
+		.pend
+
+var_fac1_greater_f	.proc
+		; -- is the float in FAC1 > the variable AY?
+		stx  P8ZP_SCRATCH_REG
+		jsr  FCOMP
+		ldx  P8ZP_SCRATCH_REG
+		cmp  #1
+		beq  +
+		lda  #0
+		rts
++		lda  #1
+		rts
+		.pend
+
+var_fac1_greatereq_f	.proc
+		; -- is the float in FAC1 >= the variable AY?
+		stx  P8ZP_SCRATCH_REG
+		jsr  FCOMP
+		ldx  P8ZP_SCRATCH_REG
+		cmp  #0
+		beq  +
+		cmp  #1
+		beq  +
+		lda  #0
+		rts
++		lda  #1
+		rts
+		.pend
+
+var_fac1_notequal_f	.proc
+		; -- are the floats numbers in FAC1 and the variable AY *not* identical?
+		stx  P8ZP_SCRATCH_REG
+		jsr  FCOMP
+		ldx  P8ZP_SCRATCH_REG
+		and  #1
+		rts
+		.pend
+
+vars_equal_f	.proc
+		; -- are the mflpt5 numbers in P8ZP_SCRATCH_W1 and AY identical?
+		sta  P8ZP_SCRATCH_W2
+		sty  P8ZP_SCRATCH_W2+1
+		ldy  #0
+		lda  (P8ZP_SCRATCH_W1),y
+		cmp  (P8ZP_SCRATCH_W2),y
+		bne  _false
+		iny
+		lda  (P8ZP_SCRATCH_W1),y
+		cmp  (P8ZP_SCRATCH_W2),y
+		bne  _false
+		iny
+		lda  (P8ZP_SCRATCH_W1),y
+		cmp  (P8ZP_SCRATCH_W2),y
+		bne  _false
+		iny
+		lda  (P8ZP_SCRATCH_W1),y
+		cmp  (P8ZP_SCRATCH_W2),y
+		bne  _false
+		iny
+		lda  (P8ZP_SCRATCH_W1),y
+		cmp  (P8ZP_SCRATCH_W2),y
+		bne  _false
+		lda  #1
+		rts
+_false		lda  #0
+		rts
+		.pend
+
+equal_f		.proc
+		; -- are the two mflpt5 numbers on the stack identical?
+		inx
+		inx
+		inx
+		inx
+		lda  P8ESTACK_LO-3,x
+		cmp  P8ESTACK_LO,x
+		bne  _equals_false
+		lda  P8ESTACK_LO-2,x
+		cmp  P8ESTACK_LO+1,x
+		bne  _equals_false
+		lda  P8ESTACK_LO-1,x
+		cmp  P8ESTACK_LO+2,x
+		bne  _equals_false
+		lda  P8ESTACK_HI-2,x
+		cmp  P8ESTACK_HI+1,x
+		bne  _equals_false
+		lda  P8ESTACK_HI-1,x
+		cmp  P8ESTACK_HI+2,x
+		bne  _equals_false
+_equals_true	lda  #1
+_equals_store	inx
+		sta  P8ESTACK_LO+1,x
+		rts
+_equals_false	lda  #0
+		beq  _equals_store
+		.pend
+
+notequal_f	.proc
+		; -- are the two mflpt5 numbers on the stack different?
+		jsr  equal_f
+		eor  #1		; invert the result
+		sta  P8ESTACK_LO+1,x
+		rts
+		.pend
+
+vars_less_f	.proc
+		; -- is float in AY < float in P8ZP_SCRATCH_W2 ?
+		jsr  MOVFM
+		lda  P8ZP_SCRATCH_W2
+		ldy  P8ZP_SCRATCH_W2+1
+		stx  P8ZP_SCRATCH_REG
+		jsr  FCOMP
+		ldx  P8ZP_SCRATCH_REG
+		cmp  #255
+		bne  +
+		lda  #1
+		rts
++		lda  #0
+		rts
+		.pend
+
+vars_lesseq_f	.proc
+		; -- is float in AY <= float in P8ZP_SCRATCH_W2 ?
+		jsr  MOVFM
+		lda  P8ZP_SCRATCH_W2
+		ldy  P8ZP_SCRATCH_W2+1
+		stx  P8ZP_SCRATCH_REG
+		jsr  FCOMP
+		ldx  P8ZP_SCRATCH_REG
+		cmp  #255
+		bne  +
+-		lda  #1
+		rts
++		cmp  #0
+		beq  -
+		lda  #0
+		rts
+		.pend
+
+less_f		.proc
+		; -- is f1 < f2?
+		jsr  compare_floats
+		cmp  #255
+		beq  compare_floats._return_true
+		bne  compare_floats._return_false
+		.pend
+
+
+lesseq_f	.proc
+		; -- is f1 <= f2?
+		jsr  compare_floats
+		cmp  #255
+		beq  compare_floats._return_true
+		cmp  #0
+		beq  compare_floats._return_true
+		bne  compare_floats._return_false
+		.pend
+
+greater_f	.proc
+		; -- is f1 > f2?
+		jsr  compare_floats
+		cmp  #1
+		beq  compare_floats._return_true
+		bne  compare_floats._return_false
+		.pend
+
+greatereq_f	.proc
+		; -- is f1 >= f2?
+		jsr  compare_floats
+		cmp  #1
+		beq  compare_floats._return_true
+		cmp  #0
+		beq  compare_floats._return_true
+		bne  compare_floats._return_false
+		.pend
+
+compare_floats	.proc
+		lda  #<fmath_float2
+		ldy  #>fmath_float2
+		jsr  pop_float
+		lda  #<fmath_float1
+		ldy  #>fmath_float1
+		jsr  pop_float
+		lda  #<fmath_float1
+		ldy  #>fmath_float1
+		jsr  MOVFM		; fac1 = flt1
+		lda  #<fmath_float2
+		ldy  #>fmath_float2
+		stx  P8ZP_SCRATCH_REG
+		jsr  FCOMP		; A = flt1 compared with flt2 (0=equal, 1=flt1>flt2, 255=flt1<flt2)
+		ldx  P8ZP_SCRATCH_REG
+		rts
+_return_false	lda  #0
+_return_result  sta  P8ESTACK_LO,x
+		dex
+		rts
+_return_true	lda  #1
+		bne  _return_result
+		.pend
+
+set_array_float_from_fac1	.proc
+		; -- set the float in FAC1 in the array (index in A, array in P8ZP_SCRATCH_W1)
+		sta  P8ZP_SCRATCH_B1
+		asl  a
+		asl  a
+		clc
+		adc  P8ZP_SCRATCH_B1
+		ldy  P8ZP_SCRATCH_W1+1
+		clc
+		adc  P8ZP_SCRATCH_W1
+		bcc  +
+		iny
++		stx  floats_store_reg
+		tax
+		jsr  MOVMF
+		ldx  floats_store_reg
+		rts
+		.pend
+
+
+set_0_array_float	.proc
+		; -- set a float in an array to zero (index in A, array in P8ZP_SCRATCH_W1)
+		sta  P8ZP_SCRATCH_B1
+		asl  a
+		asl  a
+		clc
+		adc  P8ZP_SCRATCH_B1
+		tay
+		lda  #0
+		sta  (P8ZP_SCRATCH_W1),y
+		iny
+		sta  (P8ZP_SCRATCH_W1),y
+		iny
+		sta  (P8ZP_SCRATCH_W1),y
+		iny
+		sta  (P8ZP_SCRATCH_W1),y
+		iny
+		sta  (P8ZP_SCRATCH_W1),y
+		rts
+		.pend
+
+
+set_array_float		.proc
+		; -- set a float in an array to a value (index in A, float in P8ZP_SCRATCH_W1, array in P8ZP_SCRATCH_W2)
+		sta  P8ZP_SCRATCH_B1
+		asl  a
+		asl  a
+		clc
+		adc  P8ZP_SCRATCH_B1
+		adc  P8ZP_SCRATCH_W2
+		ldy  P8ZP_SCRATCH_W2+1
+		bcc  +
+		iny
++		jmp  copy_float
+			; -- copies the 5 bytes of the mflt value pointed to by SCRATCH_ZPWORD1,
+			;    into the 5 bytes pointed to by A/Y.  Clobbers A,Y.
+		.pend
+
+
+equal_zero	.proc
+		jsr  floats.pop_float_fac1
+		jsr  floats.SIGN
+		beq  _true
+		bne  _false
+_true		lda  #1
+		sta  P8ESTACK_LO,x
+		dex
+		rts
+_false		lda  #0
+		sta  P8ESTACK_LO,x
+		dex
+		rts
+		.pend
+
+notequal_zero	.proc
+		jsr  floats.pop_float_fac1
+		jsr  floats.SIGN
+		bne  equal_zero._true
+		beq  equal_zero._false
+		.pend
+
+greater_zero	.proc
+		jsr  floats.pop_float_fac1
+		jsr  floats.SIGN
+		beq  equal_zero._false
+		bpl  equal_zero._true
+		jmp  equal_zero._false
+		.pend
+
+less_zero	.proc
+		jsr  floats.pop_float_fac1
+		jsr  floats.SIGN
+		bmi  equal_zero._true
+		jmp  equal_zero._false
+		.pend
+
+greaterequal_zero	.proc
+		jsr  floats.pop_float_fac1
+		jsr  floats.SIGN
+		bpl  equal_zero._true
+		jmp  equal_zero._false
+		.pend
+
+lessequal_zero	.proc
+		jsr  floats.pop_float_fac1
+		jsr  floats.SIGN
+		beq  equal_zero._true
+		bmi  equal_zero._true
+		jmp  equal_zero._false
+		.pend

compiler/res/prog8lib/c64/floats.p8

@@ -0,0 +1,201 @@
+; Prog8 definitions for floating point handling on the Commodore-64
+;
+; Written by Irmen de Jong (irmen@razorvine.net) - license: GNU GPL 3.0
+;
+; indent format: TABS, size=8
+
+%option enable_floats
+
+floats {
+	; ---- this block contains C-64 floating point related functions ----
+
+        const float  PI     = 3.141592653589793
+        const float  TWOPI  = 6.283185307179586
+
+        float  tempvar_swap_float     ; used for some swap() operations
+
+; ---- C64 basic and kernal ROM float constants and functions ----
+
+		; note: the fac1 and fac2 are working registers and take 6 bytes each,
+		; floats in memory  (and rom) are stored in 5-byte MFLPT packed format.
+
+
+; note: fac1/2 might get clobbered even if not mentioned in the function's name.
+; note: for subtraction and division, the left operand is in fac2, the right operand in fac1.
+
+romsub $bba2 = MOVFM(uword mflpt @ AY) clobbers(A,Y)        ; load mflpt value from memory  in A/Y into fac1
+romsub $bba6 = FREADMEM() clobbers(A,Y)                     ; load mflpt value from memory  in $22/$23 into fac1
+romsub $ba8c = CONUPK(uword mflpt @ AY) clobbers(A,Y)       ; load mflpt value from memory  in A/Y into fac2
+romsub $ba90 = FAREADMEM() clobbers(A,Y)                    ; load mflpt value from memory  in $22/$23 into fac2
+romsub $bbfc = MOVFA() clobbers(A,X)                        ; copy fac2 to fac1
+romsub $bc0c = MOVAF() clobbers(A,X)                        ; copy fac1 to fac2  (rounded)
+romsub $bc0f = MOVEF() clobbers(A,X)                        ; copy fac1 to fac2
+romsub $bbd4 = MOVMF(uword mflpt @ XY) clobbers(A,Y)        ; store fac1 to memory  X/Y as 5-byte mflpt
+
+; fac1-> signed word in Y/A (might throw ILLEGAL QUANTITY)
+; (tip: use floats.FTOSWRDAY to get A/Y output; lo/hi switched to normal little endian order)
+romsub $b1aa = FTOSWORDYA() clobbers(X) -> ubyte @ Y, ubyte @ A       ; note: calls AYINT.
+
+; fac1 -> unsigned word in Y/A (might throw ILLEGAL QUANTITY) (result also in $14/15)
+; (tip: use floats.GETADRAY to get A/Y output; lo/hi switched to normal little endian order)
+romsub $b7f7 = GETADR() clobbers(X) -> ubyte @ Y, ubyte @ A
+
+romsub $bc9b = QINT() clobbers(A,X,Y)           ; fac1 -> 4-byte signed integer in 98-101 ($62-$65), with the MSB FIRST.
+romsub $b1bf = AYINT() clobbers(A,X,Y)          ; fac1-> signed word in 100-101 ($64-$65) MSB FIRST. (might throw ILLEGAL QUANTITY)
+
+; GIVAYF: signed word in Y/A (note different lsb/msb order) -> float in fac1
+; (tip: use floats.GIVAYFAY to use A/Y input; lo/hi switched to normal order)
+; there is also floats.GIVUAYFAY - unsigned word in A/Y (lo/hi) to fac1
+; there is also floats.FREADS32  that reads from 98-101 ($62-$65) MSB FIRST
+; there is also floats.FREADUS32  that reads from 98-101 ($62-$65) MSB FIRST
+; there is also floats.FREADS24AXY  that reads signed int24 into fac1 from A/X/Y (lo/mid/hi bytes)
+romsub $b391 = GIVAYF(ubyte lo @ Y, ubyte hi @ A) clobbers(A,X,Y)
+
+romsub $b3a2 = FREADUY(ubyte value @ Y) clobbers(A,X,Y)     ; 8 bit unsigned Y -> float in fac1
+romsub $bc3c = FREADSA(byte value @ A) clobbers(A,X,Y)      ; 8 bit signed A -> float in fac1
+romsub $b7b5 = FREADSTR(ubyte length @ A) clobbers(A,X,Y)   ; str -> fac1, $22/23 must point to string, A=string length
+romsub $aabc = FPRINTLN() clobbers(A,X,Y)                   ; print string of fac1, on one line (= with newline) destroys fac1.  (consider FOUT + STROUT as well)
+romsub $bddd = FOUT() clobbers(X) -> uword @ AY             ; fac1 -> string, address returned in AY ($0100)
+
+romsub $b849 = FADDH() clobbers(A,X,Y)                      ; fac1 += 0.5, for rounding- call this before INT
+romsub $bae2 = MUL10() clobbers(A,X,Y)                      ; fac1 *= 10
+romsub $bafe = DIV10() clobbers(A,X,Y)                      ; fac1 /= 10 , CAUTION: result is always positive!
+romsub $bc5b = FCOMP(uword mflpt @ AY) clobbers(X,Y) -> ubyte @ A   ; A = compare fac1 to mflpt in A/Y, 0=equal 1=fac1 is greater, 255=fac1 is less than
+
+romsub $b86a = FADDT() clobbers(A,X,Y)                      ; fac1 += fac2
+romsub $b867 = FADD(uword mflpt @ AY) clobbers(A,X,Y)       ; fac1 += mflpt value from A/Y
+romsub $b853 = FSUBT() clobbers(A,X,Y)                      ; fac1 = fac2-fac1   mind the order of the operands
+romsub $b850 = FSUB(uword mflpt @ AY) clobbers(A,X,Y)       ; fac1 = mflpt from A/Y - fac1
+romsub $ba2b = FMULTT() clobbers(A,X,Y)                     ; fac1 *= fac2
+romsub $ba28 = FMULT(uword mflpt @ AY) clobbers(A,X,Y)      ; fac1 *= mflpt value from A/Y
+romsub $bb12 = FDIVT() clobbers(A,X,Y)                      ; fac1 = fac2/fac1  (remainder in fac2)  mind the order of the operands
+romsub $bb0f = FDIV(uword mflpt @ AY) clobbers(A,X,Y)       ; fac1 = mflpt in A/Y / fac1  (remainder in fac2)
+romsub $bf7b = FPWRT() clobbers(A,X,Y)                      ; fac1 = fac2 ** fac1
+romsub $bf78 = FPWR(uword mflpt @ AY) clobbers(A,X,Y)       ; fac1 = fac2 ** mflpt from A/Y
+romsub $bd7e = FINLOG(byte value @A) clobbers (A, X, Y)     ; fac1 += signed byte in A
+
+romsub $aed4 = NOTOP() clobbers(A,X,Y)                      ; fac1 = NOT(fac1)
+romsub $bccc = INT() clobbers(A,X,Y)                        ; INT() truncates, use FADDH first to round instead of trunc
+romsub $b9ea = LOG() clobbers(A,X,Y)                        ; fac1 = LN(fac1)  (natural log)
+romsub $bc39 = SGN() clobbers(A,X,Y)                        ; fac1 = SGN(fac1), result of SIGN (-1, 0 or 1)
+romsub $bc2b = SIGN() -> ubyte @ A                          ; SIGN(fac1) to A, $ff, $0, $1 for negative, zero, positive
+romsub $bc58 = ABS()                                        ; fac1 = ABS(fac1)
+romsub $bf71 = SQR() clobbers(A,X,Y)                        ; fac1 = SQRT(fac1)
+romsub $bf74 = SQRA() clobbers(A,X,Y)                       ; fac1 = SQRT(fac2)
+romsub $bfed = EXP() clobbers(A,X,Y)                        ; fac1 = EXP(fac1)  (e ** fac1)
+romsub $bfb4 = NEGOP() clobbers(A)                          ; switch the sign of fac1 (fac1 = -fac1)
+romsub $e097 = RND() clobbers(A,X,Y)                        ; fac1 = RND(fac1) float random number generator
+romsub $e264 = COS() clobbers(A,X,Y)                        ; fac1 = COS(fac1)
+romsub $e26b = SIN() clobbers(A,X,Y)                        ; fac1 = SIN(fac1)
+romsub $e2b4 = TAN() clobbers(A,X,Y)                        ; fac1 = TAN(fac1)
+romsub $e30e = ATN() clobbers(A,X,Y)                        ; fac1 = ATN(fac1)
+
+
+
+asmsub  FREADS32() clobbers(A,X,Y)  {
+	; ---- fac1 = signed int32 from $62-$65 big endian (MSB FIRST)
+	%asm {{
+		lda  $62
+		eor  #$ff
+		asl  a
+		lda  #0
+		ldx  #$a0
+		jmp  $bc4f		; internal BASIC routine
+	}}
+}
+
+asmsub  FREADUS32  () clobbers(A,X,Y)  {
+	; ---- fac1 = uint32 from $62-$65 big endian (MSB FIRST)
+	%asm {{
+		sec
+		lda  #0
+		ldx  #$a0
+		jmp  $bc4f		; internal BASIC routine
+	}}
+}
+
+asmsub  FREADS24AXY  (ubyte lo @ A, ubyte mid @ X, ubyte hi @ Y) clobbers(A,X,Y)  {
+	; ---- fac1 = signed int24 (A/X/Y contain lo/mid/hi bytes)
+	;      note: there is no FREADU24AXY (unsigned), use FREADUS32 instead.
+	%asm {{
+		sty  $62
+		stx  $63
+		sta  $64
+		lda  $62
+		eor  #$FF
+		asl  a
+		lda  #0
+		sta  $65
+		ldx  #$98
+		jmp  $bc4f		; internal BASIC routine
+	}}
+}
+
+asmsub  GIVUAYFAY  (uword value @ AY) clobbers(A,X,Y)  {
+	; ---- unsigned 16 bit word in A/Y (lo/hi) to fac1
+	%asm {{
+		sty  $62
+		sta  $63
+		ldx  #$90
+		sec
+		jmp  $bc49		; internal BASIC routine
+	}}
+}
+
+asmsub  GIVAYFAY  (uword value @ AY) clobbers(A,X,Y)  {
+	; ---- signed 16 bit word in A/Y (lo/hi) to float in fac1
+	%asm {{
+		sta  P8ZP_SCRATCH_REG
+		tya
+		ldy  P8ZP_SCRATCH_REG
+		jmp  GIVAYF		; this uses the inverse order, Y/A
+	}}
+}
+
+asmsub  FTOSWRDAY  () clobbers(X) -> uword @ AY  {
+	; ---- fac1 to signed word in A/Y
+	%asm {{
+		jsr  FTOSWORDYA	; note the inverse Y/A order
+		sta  P8ZP_SCRATCH_REG
+		tya
+		ldy  P8ZP_SCRATCH_REG
+		rts
+	}}
+}
+
+asmsub  GETADRAY  () clobbers(X) -> uword @ AY  {
+	; ---- fac1 to unsigned word in A/Y
+	%asm {{
+		jsr  GETADR		; this uses the inverse order, Y/A
+		sta  P8ZP_SCRATCH_B1
+		tya
+		ldy  P8ZP_SCRATCH_B1
+		rts
+	}}
+}
+
+sub  print_f  (float value) {
+	; ---- prints the floating point value (without a newline).
+	%asm {{
+		stx  floats_store_reg
+		lda  #<value
+		ldy  #>value
+		jsr  MOVFM		; load float into fac1
+		jsr  FOUT		; fac1 to string in A/Y
+		sta  P8ZP_SCRATCH_W1
+		sty  P8ZP_SCRATCH_W1+1
+		ldy  #0
+-		lda  (P8ZP_SCRATCH_W1),y
+		beq  +
+		jsr  c64.CHROUT
+		iny
+		bne  -
++		ldx  floats_store_reg
+		rts
+	}}
+}
+
+%asminclude "library:c64/floats.asm"
+%asminclude "library:c64/floats_funcs.asm"
+
+}