tweak return's use of intermediate variable

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

.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/inspectionProfiles/Project_Default.xml

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

.idea/libraries/github_hypfvieh_dbus_java.xml

@@ -1,22 +1,22 @@
 <component name="libraryTable">
   <library name="github.hypfvieh.dbus.java" type="repository">
-    <properties maven-id="com.github.hypfvieh:dbus-java:3.3.0" />
+    <properties maven-id="com.github.hypfvieh:dbus-java:3.3.1" />
     <CLASSES>
-      <root url="jar://$MAVEN_REPOSITORY$/com/github/hypfvieh/dbus-java/3.3.0/dbus-java-3.3.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/com/github/jnr/jnr-unixsocket/0.38.5/jnr-unixsocket-0.38.5.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/com/github/jnr/jnr-ffi/2.2.1/jnr-ffi-2.2.1.jar!/" />
+      <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/9.0/asm-9.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/ow2/asm/asm-commons/9.0/asm-commons-9.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/ow2/asm/asm-analysis/9.0/asm-analysis-9.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/ow2/asm/asm-tree/9.0/asm-tree-9.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/ow2/asm/asm-util/9.0/asm-util-9.0.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/0.32.3/jnr-enxio-0.32.3.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/com/github/jnr/jnr-posix/3.1.4/jnr-posix-3.1.4.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 />

.idea/libraries/hamcrest.xml

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

.idea/libraries/io_kotest_assertions_core_jvm.xml

@@ -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/junit_jupiter.xml

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

.idea/misc.xml

@@ -16,7 +16,10 @@
       </list>
     </option>
   </component>
-  <component name="ProjectRootManager" version="2" languageLevel="JDK_11" project-jdk-name="Kotlin SDK" project-jdk-type="KotlinSDK">
+  <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>
+</project>

.idea/modules.xml

@@ -2,8 +2,11 @@
 <project version="4">
   <component name="ProjectModuleManager">
     <modules>
+      <module fileurl="file://$PROJECT_DIR$/codeGeneration/codeGeneration.iml" filepath="$PROJECT_DIR$/codeGeneration/codeGeneration.iml" />
+      <module fileurl="file://$PROJECT_DIR$/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" />

.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

README.md

@@ -37,7 +37,8 @@ What does Prog8 provide?
 - small program boilerplate/compilersupport overhead
 - programs can be run multiple times without reloading because of automatic variable (re)initializations.
 - conditional branches
-- 'when' statement to provide a concise jump table alternative to if/elseif chains
+- ``when`` statement to provide a concise jump table alternative to if/elseif chains
+- ``in`` expression for concise and efficient multi-value/containment check 
 - many built-in functions such as ``sin``, ``cos``, ``rnd``, ``abs``, ``min``, ``max``, ``sqrt``, ``msb``, ``rol``, ``ror``, ``swap``, ``sort`` and ``reverse``
 - various powerful built-in libraries to do I/O, number conversions, graphics and more  
 - convenience abstractions for low level aspects such as ZeroPage handling, program startup, explicit memory addresses
@@ -52,11 +53,12 @@ What does Prog8 provide?
 - breakpoints, that let the Vice emulator drop into the monitor if execution hits them
 - source code labels automatically loaded in Vice emulator so it can show them in disassembly
 
-*Two supported compiler targets* (contributions to improve these or to add support for other machines are welcome!):
+*Multiple supported compiler targets* (contributions to improve these or to add support for other machines are welcome!):
 
-- "c64": Commodore-64  (6510 CPU = almost a 6502)
+- "c64": Commodore-64  (6502 like CPU)
+- "c128": Commodore-128  (6502 like CPU - the Z80 cpu mode is not supported)
 - "cx16": [CommanderX16](https://www.commanderx16.com)  (65c02 CPU)
-- If you only use standard kernal and prog8 library routines, it is possible to compile the *exact same program* for both machines (just change the compiler target flag)!
+- If you only use standard kernal and prog8 library routines, it is possible to compile the *exact same program* for different machines (just change the compiler target flag)
 
 
 

build.gradle

@@ -1,3 +1,10 @@
 plugins {
-    id "org.jetbrains.kotlin.jvm" version "1.5.30" apply false
+    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

@@ -1,13 +1,20 @@
-package prog8.compiler.target.cbm
+package prog8.codegen.target.cbm
 
-import prog8.compiler.CompilationOptions
-import prog8.compiler.OutputType
-import prog8.compiler.target.IAssemblyProgram
-import prog8.compiler.target.generatedLabelPrefix
+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 const val viceMonListPostfix = "vice-mon-list"
+internal fun viceMonListName(baseFilename: String) = "$baseFilename.vice-mon-list"
 
 class AssemblyProgram(
         override val valid: Boolean,
@@ -18,13 +25,21 @@ class AssemblyProgram(
     private val assemblyFile = outputDir.resolve("$name.asm")
     private val prgFile = outputDir.resolve("$name.prg")
     private val binFile = outputDir.resolve("$name.bin")
-    private val viceMonListFile = outputDir.resolve("$name.$viceMonListPostfix")
+    private val viceMonListFile = outputDir.resolve(viceMonListName(name))
+    private val listFile = outputDir.resolve("$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", "-l", viceMonListFile.toString(), "--no-monitor")
+                "--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 -> {
@@ -76,3 +91,18 @@ class AssemblyProgram(
         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/cbm/PetsciiEncoding.kt

@@ -1,4 +1,4 @@
-package prog8.compiler.target.cbm
+package prog8.codegen.target.cbm
 
 import com.github.michaelbull.result.Err
 import com.github.michaelbull.result.Ok
@@ -6,12 +6,12 @@ import com.github.michaelbull.result.Result
 import prog8.ast.antlr.escape
 import java.io.CharConversionException
 
-object Petscii {
+object PetsciiEncoding {
 
     // decoding:  from Petscii/Screencodes (0-255) to unicode
-    // character tables used from https://github.com/dj51d/cbmcodecs
+    // character tables used from https://github.com/irmen/cbmcodecs2
 
-    private val decodingPetsciiLowercase = arrayOf(
+    private val decodingPetsciiLowercase = charArrayOf(
         '\u0000',    //       0x00 -> \u0000
         '\ufffe',    //       0x01 -> UNDEFINED
         '\ufffe',    //       0x02 -> UNDEFINED
@@ -270,7 +270,7 @@ object Petscii {
         '\u2592'     //  ▒    0xFF -> MEDIUM SHADE
     )
 
-    private val decodingPetsciiUppercase = arrayOf(
+    private val decodingPetsciiUppercase = charArrayOf(
         '\u0000',    //       0x00 -> \u0000
         '\ufffe',    //       0x01 -> UNDEFINED
         '\ufffe',    //       0x02 -> UNDEFINED
@@ -369,13 +369,13 @@ object Petscii {
         '\u2190',    //  ←    0x5F -> LEFTWARDS ARROW
         '\u2500',    //  ─    0x60 -> BOX DRAWINGS LIGHT HORIZONTAL
         '\u2660',    //  ♠    0x61 -> BLACK SPADE SUIT
-        '\u2502',    //  │    0x62 -> BOX DRAWINGS LIGHT VERTICAL
-        '\u2500',    //  ─    0x63 -> BOX DRAWINGS LIGHT HORIZONTAL
-        '\uf122',    //      0x64 -> BOX DRAWINGS LIGHT HORIZONTAL ONE QUARTER UP (CUS)
-        '\uf123',    //      0x65 -> BOX DRAWINGS LIGHT HORIZONTAL TWO QUARTERS UP (CUS)
-        '\uf124',    //      0x66 -> BOX DRAWINGS LIGHT HORIZONTAL ONE QUARTER DOWN (CUS)
-        '\uf126',    //      0x67 -> BOX DRAWINGS LIGHT VERTICAL ONE QUARTER LEFT (CUS)
-        '\uf128',    //      0x68 -> BOX DRAWINGS LIGHT VERTICAL ONE QUARTER RIGHT (CUS)
+        '\uf13c',    //  │    0x62 -> BOX DRAWINGS LIGHT VERTICAL ONE EIGHTH LEFT (CUS)
+        '\uf13b',    //  ─    0x63 -> BOX DRAWINGS LIGHT HORIZONTAL ONE EIGHTH UP (CUS)
+        '\uf122',    //      0x64 -> BOX DRAWINGS LIGHT HORIZONTAL TWO EIGHTHS UP (CUS)
+        '\uf123',    //      0x65 -> BOX DRAWINGS LIGHT HORIZONTAL THREE EIGHTHS UP (CUS)
+        '\uf124',    //      0x66 -> BOX DRAWINGS LIGHT HORIZONTAL ONE EIGHTH DOWN (CUS)
+        '\uf126',    //      0x67 -> BOX DRAWINGS LIGHT VERTICAL TWO EIGHTHS LEFT (CUS)
+        '\uf128',    //      0x68 -> BOX DRAWINGS LIGHT VERTICAL ONE EIGHTH RIGHT (CUS)
         '\u256e',    //  ╮    0x69 -> BOX DRAWINGS LIGHT ARC DOWN AND LEFT
         '\u2570',    //  ╰    0x6A -> BOX DRAWINGS LIGHT ARC UP AND RIGHT
         '\u256f',    //  ╯    0x6B -> BOX DRAWINGS LIGHT ARC UP AND LEFT
@@ -385,14 +385,14 @@ object Petscii {
         '\uf12b',    //      0x6F -> ONE EIGHTH BLOCK DOWN AND RIGHT (CUS)
         '\uf12c',    //      0x70 -> ONE EIGHTH BLOCK DOWN AND LEFT (CUS)
         '\u25cf',    //  ●    0x71 -> BLACK CIRCLE
-        '\uf125',    //      0x72 -> BOX DRAWINGS LIGHT HORIZONTAL TWO QUARTERS DOWN (CUS)
+        '\uf125',    //      0x72 -> BOX DRAWINGS LIGHT HORIZONTAL TWO EIGHTHS DOWN (CUS)
         '\u2665',    //  ♥    0x73 -> BLACK HEART SUIT
-        '\uf127',    //      0x74 -> BOX DRAWINGS LIGHT VERTICAL TWO QUARTERS LEFT (CUS)
+        '\uf127',    //      0x74 -> BOX DRAWINGS LIGHT VERTICAL THREE EIGHTHS LEFT (CUS)
         '\u256d',    //  ╭    0x75 -> BOX DRAWINGS LIGHT ARC DOWN AND RIGHT
         '\u2573',    //  ╳    0x76 -> BOX DRAWINGS LIGHT DIAGONAL CROSS
         '\u25cb',    //  ○    0x77 -> WHITE CIRCLE
         '\u2663',    //  ♣    0x78 -> BLACK CLUB SUIT
-        '\uf129',    //      0x79 -> BOX DRAWINGS LIGHT VERTICAL TWO QUARTERS RIGHT (CUS)
+        '\uf129',    //      0x79 -> BOX DRAWINGS LIGHT VERTICAL TWO EIGHTS RIGHT (CUS)
         '\u2666',    //  ♦    0x7A -> BLACK DIAMOND SUIT
         '\u253c',    //  ┼    0x7B -> BOX DRAWINGS LIGHT VERTICAL AND HORIZONTAL
         '\uf12e',    //      0x7C -> LEFT HALF BLOCK MEDIUM SHADE (CUS)
@@ -465,13 +465,13 @@ object Petscii {
         '\u259a',    //  ▚    0xBF -> QUADRANT UPPER LEFT AND LOWER RIGHT
         '\u2500',    //  ─    0xC0 -> BOX DRAWINGS LIGHT HORIZONTAL
         '\u2660',    //  ♠    0xC1 -> BLACK SPADE SUIT
-        '\u2502',    //  │    0xC2 -> BOX DRAWINGS LIGHT VERTICAL
-        '\u2500',    //  ─    0xC3 -> BOX DRAWINGS LIGHT HORIZONTAL
-        '\uf122',    //      0xC4 -> BOX DRAWINGS LIGHT HORIZONTAL ONE QUARTER UP (CUS)
-        '\uf123',    //      0xC5 -> BOX DRAWINGS LIGHT HORIZONTAL TWO QUARTERS UP (CUS)
-        '\uf124',    //      0xC6 -> BOX DRAWINGS LIGHT HORIZONTAL ONE QUARTER DOWN (CUS)
-        '\uf126',    //      0xC7 -> BOX DRAWINGS LIGHT VERTICAL ONE QUARTER LEFT (CUS)
-        '\uf128',    //      0xC8 -> BOX DRAWINGS LIGHT VERTICAL ONE QUARTER RIGHT (CUS)
+        '\uf13c',    //  │    0xC2 -> BOX DRAWINGS LIGHT VERTICAL ONE EIGHTH LEFT (CUS)
+        '\uf13b',    //  ─    0xC3 -> BOX DRAWINGS LIGHT HORIZONTAL ONE EIGHTH UP (CUS)
+        '\uf122',    //      0xC4 -> BOX DRAWINGS LIGHT HORIZONTAL TWO EIGHTHS UP (CUS)
+        '\uf123',    //      0xC5 -> BOX DRAWINGS LIGHT HORIZONTAL THREE EIGHTHS UP (CUS)
+        '\uf124',    //      0xC6 -> BOX DRAWINGS LIGHT HORIZONTAL ONE EIGHTH DOWN (CUS)
+        '\uf126',    //      0xC7 -> BOX DRAWINGS LIGHT VERTICAL TWO EIGHTHS LEFT (CUS)
+        '\uf128',    //      0xC8 -> BOX DRAWINGS LIGHT VERTICAL ONE EIGHTH RIGHT (CUS)
         '\u256e',    //  ╮    0xC9 -> BOX DRAWINGS LIGHT ARC DOWN AND LEFT
         '\u2570',    //  ╰    0xCA -> BOX DRAWINGS LIGHT ARC UP AND RIGHT
         '\u256f',    //  ╯    0xCB -> BOX DRAWINGS LIGHT ARC UP AND LEFT
@@ -481,14 +481,14 @@ object Petscii {
         '\uf12b',    //      0xCF -> ONE EIGHTH BLOCK DOWN AND RIGHT (CUS)
         '\uf12c',    //      0xD0 -> ONE EIGHTH BLOCK DOWN AND LEFT (CUS)
         '\u25cf',    //  ●    0xD1 -> BLACK CIRCLE
-        '\uf125',    //      0xD2 -> BOX DRAWINGS LIGHT HORIZONTAL TWO QUARTERS DOWN (CUS)
+        '\uf125',    //      0xD2 -> BOX DRAWINGS LIGHT HORIZONTAL TWO EIGHTS DOWN (CUS)
         '\u2665',    //  ♥    0xD3 -> BLACK HEART SUIT
-        '\uf127',    //      0xD4 -> BOX DRAWINGS LIGHT VERTICAL TWO QUARTERS LEFT (CUS)
+        '\uf127',    //      0xD4 -> BOX DRAWINGS LIGHT VERTICAL THREE EIGHTS LEFT (CUS)
         '\u256d',    //  ╭    0xD5 -> BOX DRAWINGS LIGHT ARC DOWN AND LEFT
         '\u2573',    //  ╳    0xD6 -> BOX DRAWINGS LIGHT DIAGONAL CROSS
         '\u25cb',    //  ○    0xD7 -> WHITE CIRCLE
         '\u2663',    //  ♣    0xD8 -> BLACK CLUB SUIT
-        '\uf129',    //      0xD9 -> BOX DRAWINGS LIGHT VERTICAL TWO QUARTERS RIGHT (CUS)
+        '\uf129',    //      0xD9 -> BOX DRAWINGS LIGHT VERTICAL TWO EIGHTS RIGHT (CUS)
         '\u2666',    //  ♦    0xDA -> BLACK DIAMOND SUIT
         '\u253c',    //  ┼    0xDB -> BOX DRAWINGS LIGHT VERTICAL AND HORIZONTAL
         '\uf12e',    //      0xDC -> LEFT HALF BLOCK MEDIUM SHADE (CUS)
@@ -529,7 +529,7 @@ object Petscii {
         '\u03c0'     //  π    0xFF -> GREEK SMALL LETTER PI
     )
 
-    private val decodingScreencodeLowercase = arrayOf(
+    private val decodingScreencodeLowercase = charArrayOf(
         '@'     ,    //  @    0x00 -> COMMERCIAL AT
         'a'     ,    //  a    0x01 -> LATIN SMALL LETTER A
         'b'     ,    //  b    0x02 -> LATIN SMALL LETTER B
@@ -788,7 +788,7 @@ object Petscii {
         '\ufffe'     //       0xFF -> UNDEFINED
     )
 
-    private val decodingScreencodeUppercase = arrayOf(
+    private val decodingScreencodeUppercase = charArrayOf(
         '@'     ,    //  @    0x00 -> COMMERCIAL AT
         'A'     ,    //  A    0x01 -> LATIN CAPITAL LETTER A
         'B'     ,    //  B    0x02 -> LATIN CAPITAL LETTER B
@@ -855,13 +855,13 @@ object Petscii {
         '?'     ,    //  ?    0x3F -> QUESTION MARK
         '\u2500',    //  ─    0x40 -> BOX DRAWINGS LIGHT HORIZONTAL
         '\u2660',    //  ♠    0x41 -> BLACK SPADE SUIT
-        '\u2502',    //  │    0x42 -> BOX DRAWINGS LIGHT VERTICAL
-        '\u2500',    //  ─    0x43 -> BOX DRAWINGS LIGHT HORIZONTAL
-        '\uf122',    //      0x44 -> BOX DRAWINGS LIGHT HORIZONTAL ONE QUARTER UP (CUS)
-        '\uf123',    //      0x45 -> BOX DRAWINGS LIGHT HORIZONTAL TWO QUARTERS UP (CUS)
-        '\uf124',    //      0x46 -> BOX DRAWINGS LIGHT HORIZONTAL ONE QUARTER DOWN (CUS)
-        '\uf126',    //      0x47 -> BOX DRAWINGS LIGHT VERTICAL ONE QUARTER LEFT (CUS)
-        '\uf128',    //      0x48 -> BOX DRAWINGS LIGHT VERTICAL ONE QUARTER RIGHT (CUS)
+        '\uf13c',    //  │    0x42 -> BOX DRAWINGS LIGHT VERTICAL ONE EIGHTH LEFT (CUS)
+        '\uf13b',    //  ─    0x43 -> BOX DRAWINGS LIGHT HORIZONTAL ONE EIGHTH UP (CUS)
+        '\uf122',    //      0x44 -> BOX DRAWINGS LIGHT HORIZONTAL TWO EIGHTHS UP (CUS)
+        '\uf123',    //      0x45 -> BOX DRAWINGS LIGHT HORIZONTAL THREE EIGHTHS UP (CUS
+        '\uf124',    //      0x46 -> BOX DRAWINGS LIGHT HORIZONTAL ONE EIGHTH DOWN (CUS)
+        '\uf126',    //      0x47 -> BOX DRAWINGS LIGHT VERTICAL TWO EIGHTHS LEFT (CUS)
+        '\uf128',    //      0x48 -> BOX DRAWINGS LIGHT VERTICAL ONE EIGHTH RIGHT (CUS)
         '\u256e',    //  ╮    0x49 -> BOX DRAWINGS LIGHT ARC DOWN AND LEFT
         '\u2570',    //  ╰    0x4A -> BOX DRAWINGS LIGHT ARC UP AND RIGHT
         '\u256f',    //  ╯    0x4B -> BOX DRAWINGS LIGHT ARC UP AND LEFT
@@ -871,14 +871,14 @@ object Petscii {
         '\uf12b',    //      0x4F -> ONE EIGHTH BLOCK DOWN AND RIGHT (CUS)
         '\uf12c',    //      0x50 -> ONE EIGHTH BLOCK DOWN AND LEFT (CUS)
         '\u25cf',    //  ●    0x51 -> BLACK CIRCLE
-        '\uf125',    //      0x52 -> BOX DRAWINGS LIGHT HORIZONTAL TWO QUARTERS DOWN (CUS)
+        '\uf125',    //      0x52 -> BOX DRAWINGS LIGHT HORIZONTAL TWO EIGHTS DOWN (CUS)
         '\u2665',    //  ♥    0x53 -> BLACK HEART SUIT
-        '\uf127',    //      0x54 -> BOX DRAWINGS LIGHT VERTICAL TWO QUARTERS LEFT (CUS)
+        '\uf127',    //      0x54 -> BOX DRAWINGS LIGHT VERTICAL THREE EIGHTS LEFT (CUS)
         '\u256d',    //  ╭    0x55 -> BOX DRAWINGS LIGHT ARC DOWN AND RIGHT
         '\u2573',    //  ╳    0x56 -> BOX DRAWINGS LIGHT DIAGONAL CROSS
         '\u25cb',    //  ○    0x57 -> WHITE CIRCLE
         '\u2663',    //  ♣    0x58 -> BLACK CLUB SUIT
-        '\uf129',    //      0x59 -> BOX DRAWINGS LIGHT VERTICAL TWO QUARTERS RIGHT (CUS)
+        '\uf129',    //      0x59 -> BOX DRAWINGS LIGHT VERTICAL TWO EIGHTS RIGHT (CUS)
         '\u2666',    //  ♦    0x5A -> BLACK DIAMOND SUIT
         '\u253c',    //  ┼    0x5B -> BOX DRAWINGS LIGHT VERTICAL AND HORIZONTAL
         '\uf12e',    //      0x5C -> LEFT HALF BLOCK MEDIUM SHADE (CUS)
@@ -1065,15 +1065,15 @@ object Petscii {
             else -> chr
         }
 
-    fun encodePetscii(text: String, lowercase: Boolean = false): Result<List<Short>, CharConversionException> {
-        fun encodeChar(chr3: Char, lowercase: Boolean): Short {
+    fun encodePetscii(text: String, lowercase: Boolean = false): Result<List<UByte>, CharConversionException> {
+        fun encodeChar(chr3: Char, lowercase: Boolean): UByte {
             val chr = replaceSpecial(chr3)
             val screencode = if(lowercase) encodingPetsciiLowercase[chr] else encodingPetsciiUppercase[chr]
-            return screencode?.toShort() ?: when (chr) {
-                '\u0000' -> 0.toShort()
+            return screencode?.toUByte() ?: when (chr) {
+                '\u0000' -> 0u
                 in '\u8000'..'\u80ff' -> {
                     // special case: take the lower 8 bit hex value directly
-                    (chr.code - 0x8000).toShort()
+                    (chr.code - 0x8000).toUByte()
                 }
                 else -> {
                     val case = if (lowercase) "lower" else "upper"
@@ -1095,27 +1095,28 @@ object Petscii {
         }
     }
 
-    fun decodePetscii(petscii: Iterable<Short>, lowercase: Boolean = false): String {
-        return petscii.map {
-            val code = it.toInt()
-            try {
+    fun decodePetscii(petscii: Iterable<UByte>, lowercase: Boolean = false): Result<String, CharConversionException> {
+        return try {
+            Ok(petscii.map {
+                val code = it.toInt()
+                if(code<0 || code>= decodingPetsciiLowercase.size)
+                    throw CharConversionException("petscii $code out of range 0..${decodingPetsciiLowercase.size-1}")
                 if(lowercase) decodingPetsciiLowercase[code] else decodingPetsciiUppercase[code]
-            } catch(x: CharConversionException) {
-                // TODO this CharConversionException can never occur?? also clean up ICompilationTarget.decodeString?
-                if(lowercase) decodingPetsciiUppercase[code] else decodingPetsciiLowercase[code]
-            }
-        }.joinToString("")
+            }.joinToString(""))
+        } catch(ce: CharConversionException) {
+            return Err(ce)
+        }
     }
 
-    fun encodeScreencode(text: String, lowercase: Boolean = false): Result<List<Short>, CharConversionException> {
-        fun encodeChar(chr3: Char, lowercase: Boolean): Short {
+    fun encodeScreencode(text: String, lowercase: Boolean = false): Result<List<UByte>, CharConversionException> {
+        fun encodeChar(chr3: Char, lowercase: Boolean): UByte {
             val chr = replaceSpecial(chr3)
             val screencode = if(lowercase) encodingScreencodeLowercase[chr] else encodingScreencodeUppercase[chr]
-            return screencode?.toShort() ?: when (chr) {
-                '\u0000' -> 0.toShort()
+            return screencode?.toUByte() ?: when (chr) {
+                '\u0000' -> 0u
                 in '\u8000'..'\u80ff' -> {
                     // special case: take the lower 8 bit hex value directly
-                    (chr.code - 0x8000).toShort()
+                    (chr.code - 0x8000).toUByte()
                 }
                 else -> {
                     val case = if (lowercase) "lower" else "upper"
@@ -1137,48 +1138,50 @@ object Petscii {
         }
     }
 
-    fun decodeScreencode(screencode: Iterable<Short>, lowercase: Boolean = false): String {
-        return screencode.map {
-            val code = it.toInt()
-            try {
+    fun decodeScreencode(screencode: Iterable<UByte>, lowercase: Boolean = false): Result<String, CharConversionException> {
+        return try {
+            Ok(screencode.map {
+                val code = it.toInt()
+                if(code<0 || code>= decodingScreencodeLowercase.size)
+                    throw CharConversionException("screencode $code out of range 0..${decodingScreencodeLowercase.size-1}")
                 if (lowercase) decodingScreencodeLowercase[code] else decodingScreencodeUppercase[code]
-            } catch (x: CharConversionException) {
-                // TODO this CharConversionException can never occur?? also clean up ICompilationTarget.decodeString?
-                if (lowercase) decodingScreencodeUppercase[code] else decodingScreencodeLowercase[code]
-            }
-        }.joinToString("")
+            }.joinToString(""))
+        } catch(ce: CharConversionException) {
+            Err(ce)
+        }
     }
 
-    fun petscii2scr(petscii_code: Short, inverseVideo: Boolean): Result<Short, CharConversionException> {
-        val code = when {
-            petscii_code <= 0x1f -> petscii_code + 128
-            petscii_code <= 0x3f -> petscii_code.toInt()
-            petscii_code <= 0x5f -> petscii_code - 64
-            petscii_code <= 0x7f -> petscii_code - 32
-            petscii_code <= 0x9f -> petscii_code + 64
-            petscii_code <= 0xbf -> petscii_code - 64
-            petscii_code <= 0xfe -> petscii_code - 128
-            petscii_code == 255.toShort() -> 95
+    fun petscii2scr(petscii_code: UByte, inverseVideo: Boolean): Result<UByte, CharConversionException> {
+        val code: UInt = when {
+            petscii_code <= 0x1fu -> petscii_code + 128u
+            petscii_code <= 0x3fu -> petscii_code.toUInt()
+            petscii_code <= 0x5fu -> petscii_code - 64u
+            petscii_code <= 0x7fu -> petscii_code - 32u
+            petscii_code <= 0x9fu -> petscii_code + 64u
+            petscii_code <= 0xbfu -> petscii_code - 64u
+            petscii_code <= 0xfeu -> petscii_code - 128u
+            petscii_code == 255.toUByte() -> 95u
             else -> return Err(CharConversionException("petscii code out of range"))
         }
-        if(inverseVideo)
-            return Ok((code or 0x80).toShort())
-        return Ok(code.toShort())
+        if(inverseVideo) {
+            return Ok((code or 0x80u).toUByte())
+        }
+        return Ok(code.toUByte())
     }
 
-    fun scr2petscii(screencode: Short): Result<Short, CharConversionException> {
-        val petscii = when {
-            screencode <= 0x1f -> screencode + 64
-            screencode <= 0x3f -> screencode.toInt()
-            screencode <= 0x5d -> screencode +123
-            screencode == 0x5e.toShort() -> 255
-            screencode == 0x5f.toShort() -> 223
-            screencode <= 0x7f -> screencode + 64
-            screencode <= 0xbf -> screencode - 128
-            screencode <= 0xfe -> screencode - 64
-            screencode == 255.toShort() -> 191
+    fun scr2petscii(screencode: UByte): Result<UByte, CharConversionException> {
+        val petscii: UInt = when {
+            screencode <= 0x1fu -> screencode + 64u
+            screencode <= 0x3fu -> screencode.toUInt()
+            screencode <= 0x5du -> screencode +123u
+            screencode == 0x5e.toUByte() -> 255u
+            screencode == 0x5f.toUByte() -> 223u
+            screencode <= 0x7fu -> screencode + 64u
+            screencode <= 0xbfu -> screencode - 128u
+            screencode <= 0xfeu -> screencode - 64u
+            screencode == 255.toUByte() -> 191u
             else -> return Err(CharConversionException("screencode out of range"))
         }
-        return Ok(petscii.toShort())
+        return Ok(petscii.toUByte())
     }
 }

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/BuiltinFunctionsAsmGen.kt

@@ -1,4 +1,4 @@
-package prog8.compiler.target.cpu6502.codegen
+package prog8.codegen.target.cpu6502.codegen
 
 import prog8.ast.IFunctionCall
 import prog8.ast.Node
@@ -10,16 +10,17 @@ import prog8.ast.statements.DirectMemoryWrite
 import prog8.ast.statements.FunctionCallStatement
 import prog8.ast.statements.Subroutine
 import prog8.ast.toHex
-import prog8.compiler.AssemblyError
-import prog8.compiler.functions.FSignature
-import prog8.compiler.target.CpuType
-import prog8.compiler.target.Cx16Target
-import prog8.compiler.target.cpu6502.codegen.assignment.*
-import prog8.compiler.target.subroutineFloatEvalResultVar2
+import prog8.codegen.target.AssemblyError
+import prog8.codegen.target.Cx16Target
+import prog8.codegen.target.cpu6502.codegen.assignment.*
+import prog8.compilerinterface.BuiltinFunctions
+import prog8.compilerinterface.CpuType
+import prog8.compilerinterface.FSignature
+
 
 internal class BuiltinFunctionsAsmGen(private val program: Program, private val asmgen: AsmGen, private val assignAsmGen: AssignmentAsmGen) {
 
-    internal fun translateFunctioncallExpression(fcall: FunctionCall, func: FSignature, resultToStack: Boolean, resultRegister: RegisterOrPair?) {
+    internal fun translateFunctioncallExpression(fcall: FunctionCallExpression, func: FSignature, resultToStack: Boolean, resultRegister: RegisterOrPair?) {
         translateFunctioncall(fcall, func, discardResult = false, resultToStack = resultToStack, resultRegister = resultRegister)
     }
 
@@ -27,6 +28,37 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
         translateFunctioncall(fcall, func, discardResult = true, resultToStack = false, resultRegister = null)
     }
 
+    internal fun translateFunctioncall(name: String, args: List<AsmAssignSource>, isStatement: Boolean, scope: Subroutine): DataType {
+        val func = BuiltinFunctions.getValue(name)
+        val argExpressions = args.map { src ->
+            when(src.kind) {
+                SourceStorageKind.LITERALNUMBER -> src.number!!
+                SourceStorageKind.EXPRESSION -> src.expression!!
+                SourceStorageKind.ARRAY -> src.array!!
+                else -> {
+                    // TODO make it so that we can assign efficiently from something else as an expression....namely: register(s)
+                    //      this is useful in pipe expressions for instance, to skip the use of a temporary variable
+                    //      but for now, just assign it to a temporary variable and use that as a source
+                    val tempvar = asmgen.getTempVarName(src.datatype)
+                    val assignTempvar = AsmAssignment(
+                        src,
+                        AsmAssignTarget(TargetStorageKind.VARIABLE, program, asmgen, src.datatype, scope, variableAsmName = asmgen.asmVariableName(tempvar)),
+                        false, program.memsizer, Position.DUMMY
+                    )
+                    assignAsmGen.translateNormalAssignment(assignTempvar)
+                    // now use an expression to assign this tempvar
+                    val ident = IdentifierReference(tempvar, Position.DUMMY)
+                    ident.linkParents(scope)
+                    ident
+                }
+            }
+        }.toMutableList()
+        val fcall = FunctionCallExpression(IdentifierReference(listOf(name), Position.DUMMY), argExpressions, Position.DUMMY)
+        fcall.linkParents(scope)
+        translateFunctioncall(fcall, func, discardResult = false, resultToStack = false, null)
+        return if(isStatement) DataType.UNDEFINED else func.known_returntype!!
+    }
+
     private fun translateFunctioncall(fcall: IFunctionCall, func: FSignature, discardResult: Boolean, resultToStack: Boolean, resultRegister: RegisterOrPair?) {
         if (discardResult && func.pure)
             return  // can just ignore the whole function call altogether
@@ -46,7 +78,9 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
             "sum" -> funcSum(fcall, resultToStack, resultRegister, sscope)
             "any", "all" -> funcAnyAll(fcall, func, resultToStack, resultRegister, sscope)
             "sin8", "sin8u", "sin16", "sin16u",
-            "cos8", "cos8u", "cos16", "cos16u" -> funcSinCosInt(fcall, func, resultToStack, resultRegister, sscope)
+            "sinr8", "sinr8u", "sinr16", "sinr16u",
+            "cos8", "cos8u", "cos16", "cos16u",
+            "cosr8", "cosr8u", "cosr16", "cosr16u" -> funcSinCosInt(fcall, func, resultToStack, resultRegister, sscope)
             "sgn" -> funcSgn(fcall, func, resultToStack, resultRegister, sscope)
             "sin", "cos", "tan", "atan",
             "ln", "log2", "sqrt", "rad",
@@ -64,7 +98,14 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
             "peekw" -> funcPeekW(fcall, resultToStack, resultRegister)
             "peek" -> throw AssemblyError("peek() should have been replaced by @()")
             "pokew" -> funcPokeW(fcall)
+            "pokemon" -> { /* meme function */ }
             "poke" -> throw AssemblyError("poke() should have been replaced by @()")
+            "push", "pushw" -> funcPush(fcall, func)
+            "pop", "popw" -> funcPop(fcall, func)
+            "rsave" -> funcRsave()
+            "rsavex" -> funcRsaveX()
+            "rrestore" -> funcRrestore()
+            "rrestorex" -> funcRrestoreX()
             "cmp" -> funcCmp(fcall)
             "callfar" -> funcCallFar(fcall)
             "callrom" -> funcCallRom(fcall)
@@ -72,6 +113,168 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
         }
     }
 
+    private fun funcRsave() {
+        if (asmgen.isTargetCpu(CpuType.CPU65c02))
+            asmgen.out("""
+                php
+                pha
+                phy
+                phx""")
+        else
+            // see http://6502.org/tutorials/register_preservation.html
+            asmgen.out("""
+                php
+                sta  P8ZP_SCRATCH_REG
+                pha
+                txa
+                pha
+                tya
+                pha
+                lda  P8ZP_SCRATCH_REG""")
+    }
+
+    private fun funcRsaveX() {
+        if (asmgen.isTargetCpu(CpuType.CPU65c02))
+            asmgen.out("  phx")
+        else
+            asmgen.out("  txa |  pha")
+    }
+
+    private fun funcRrestore() {
+        if (asmgen.isTargetCpu(CpuType.CPU65c02))
+            asmgen.out("""
+                plx
+                ply
+                pla
+                plp""")
+        else
+            asmgen.out("""
+                pla
+                tay
+                pla
+                tax
+                pla
+                plp""")
+    }
+
+    private fun funcRrestoreX() {
+        if (asmgen.isTargetCpu(CpuType.CPU65c02))
+            asmgen.out("  plx")
+        else
+            asmgen.out("  sta  P8ZP_SCRATCH_B1 |  pla |  tax |  lda  P8ZP_SCRATCH_B1")
+    }
+
+    private fun funcPop(fcall: IFunctionCall, func: FSignature) {
+        // note: because A is pushed first so popped last, saving A is often not required here.
+        require(fcall.args[0] is IdentifierReference) {
+            "attempt to pop a value into a differently typed variable, or in something else that isn't supported ${(fcall as Node).position}"
+        }
+        val target = (fcall.args[0] as IdentifierReference).targetVarDecl(program)!!
+        val parameter = target.subroutineParameter
+        if(parameter!=null) {
+            val sub = parameter.definingSubroutine!!
+            require(sub.isAsmSubroutine) {
+                "push/pop arg passing only supported on asmsubs ${(fcall as Node).position}"
+            }
+            val shouldKeepA = sub.asmParameterRegisters.any { it.registerOrPair==RegisterOrPair.AX || it.registerOrPair==RegisterOrPair.AY }
+            val reg = sub.asmParameterRegisters[sub.parameters.indexOf(parameter)]
+            if(reg.statusflag!=null) {
+                if(shouldKeepA)
+                    asmgen.out("  sta  P8ZP_SCRATCH_REG")
+                asmgen.out("""
+                    clc
+                    pla
+                    beq  +
+                    sec
++""")
+                if(shouldKeepA)
+                    asmgen.out("  lda  P8ZP_SCRATCH_REG")
+            }
+            else {
+                if (func.name == "pop") {
+                    if (asmgen.isTargetCpu(CpuType.CPU65c02)) {
+                        when (reg.registerOrPair) {
+                            RegisterOrPair.A -> asmgen.out("  pla")
+                            RegisterOrPair.X -> asmgen.out("  plx")
+                            RegisterOrPair.Y -> asmgen.out("  ply")
+                            in Cx16VirtualRegisters -> asmgen.out("  pla |  sta  cx16.${reg.registerOrPair!!.name.lowercase()}")
+                            else -> throw AssemblyError("invalid target register ${reg.registerOrPair}")
+                        }
+                    } else {
+                        when (reg.registerOrPair) {
+                            RegisterOrPair.A -> asmgen.out("  pla")
+                            RegisterOrPair.X -> {
+                                if(shouldKeepA)
+                                    asmgen.out("  sta  P8ZP_SCRATCH_REG |  pla |  tax |  lda  P8ZP_SCRATCH_REG")
+                                else
+                                    asmgen.out("  pla |  tax")
+                            }
+                            RegisterOrPair.Y -> {
+                                if(shouldKeepA)
+                                    asmgen.out("  sta  P8ZP_SCRATCH_REG |  pla |  tay |  lda  P8ZP_SCRATCH_REG")
+                                else
+                                    asmgen.out("  pla |  tay")
+                            }
+                            in Cx16VirtualRegisters -> asmgen.out("  pla |  sta  cx16.${reg.registerOrPair!!.name.lowercase()}")
+                            else -> throw AssemblyError("invalid target register ${reg.registerOrPair}")
+                        }
+                    }
+                } else {
+                    // word pop
+                    if (asmgen.isTargetCpu(CpuType.CPU65c02))
+                        when (reg.registerOrPair) {
+                            RegisterOrPair.AX -> asmgen.out("  plx |  pla")
+                            RegisterOrPair.AY -> asmgen.out("  ply |  pla")
+                            RegisterOrPair.XY -> asmgen.out("  ply |  plx")
+                            in Cx16VirtualRegisters -> {
+                                val regname = reg.registerOrPair!!.name.lowercase()
+                                asmgen.out("  pla |  sta  cx16.$regname+1 |  pla |  sta  cx16.$regname")
+                            }
+                            else -> throw AssemblyError("invalid target register ${reg.registerOrPair}")
+                        }
+                    else {
+                        when (reg.registerOrPair) {
+                            RegisterOrPair.AX -> asmgen.out("  pla |  tax |  pla")
+                            RegisterOrPair.AY -> asmgen.out("  pla |  tay |  pla")
+                            RegisterOrPair.XY -> asmgen.out("  pla |  tay |  pla |  tax")
+                            in Cx16VirtualRegisters -> {
+                                val regname = reg.registerOrPair!!.name.lowercase()
+                                asmgen.out("  pla |  sta  cx16.$regname+1 |  pla |  sta  cx16.$regname")
+                            }
+                            else -> throw AssemblyError("invalid target register ${reg.registerOrPair}")
+                        }
+                    }
+                }
+            }
+        } else {
+            val tgt = AsmAssignTarget(TargetStorageKind.VARIABLE, program, asmgen, target.datatype, (fcall as Node).definingSubroutine, variableAsmName = asmgen.asmVariableName(target.name))
+            if (func.name == "pop") {
+                asmgen.out("  pla")
+                asmgen.assignRegister(RegisterOrPair.A, tgt)
+            } else {
+                if (asmgen.isTargetCpu(CpuType.CPU65c02))
+                    asmgen.out("  ply |  pla")
+                else
+                    asmgen.out("  pla |  tay |  pla")
+                asmgen.assignRegister(RegisterOrPair.AY, tgt)
+            }
+        }
+    }
+
+    private fun funcPush(fcall: IFunctionCall, func: FSignature) {
+        val signed = fcall.args[0].inferType(program).oneOf(DataType.BYTE, DataType.WORD)
+        if(func.name=="push") {
+            asmgen.assignExpressionToRegister(fcall.args[0], RegisterOrPair.A, signed)
+            asmgen.out("  pha")
+        } else {
+            asmgen.assignExpressionToRegister(fcall.args[0], RegisterOrPair.AY, signed)
+            if (asmgen.isTargetCpu(CpuType.CPU65c02))
+                asmgen.out("  pha |  phy")
+            else
+                asmgen.out("  pha |  tya |  pha")
+        }
+    }
+
     private fun funcCallFar(fcall: IFunctionCall) {
         if(asmgen.options.compTarget !is Cx16Target)
             throw AssemblyError("callfar only works on cx16 target at this time")
@@ -87,7 +290,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
             throw AssemblyError("callfar done on bank 0 which is reserved for the kernal")
 
         val argAddrArg = fcall.args[2]
-        if(argAddrArg.constValue(program)?.number == 0) {
+        if(argAddrArg.constValue(program)?.number == 0.0) {
             asmgen.out("""
                 jsr  cx16.jsrfar
                 .word  ${address.toHex()}
@@ -132,7 +335,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
             throw AssemblyError("callrom bank must be <32")
 
         val argAddrArg = fcall.args[2]
-        if(argAddrArg.constValue(program)?.number == 0) {
+        if(argAddrArg.constValue(program)?.number == 0.0) {
             asmgen.out("""
                 lda  $01
                 pha
@@ -177,8 +380,8 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
     private fun funcCmp(fcall: IFunctionCall) {
         val arg1 = fcall.args[0]
         val arg2 = fcall.args[1]
-        val dt1 = arg1.inferType(program).getOr(DataType.UNDEFINED)
-        val dt2 = arg2.inferType(program).getOr(DataType.UNDEFINED)
+        val dt1 = arg1.inferType(program).getOrElse { throw AssemblyError("unknown dt") }
+        val dt2 = arg2.inferType(program).getOrElse { throw AssemblyError("unknown dt") }
         if(dt1 in ByteDatatypes) {
             if(dt2 in ByteDatatypes) {
                 when (arg2) {
@@ -188,7 +391,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                     }
                     is NumericLiteralValue -> {
                         asmgen.assignExpressionToRegister(arg1, RegisterOrPair.A)
-                        asmgen.out("  cmp  #${arg2.number}")
+                        asmgen.out("  cmp  #${arg2.number.toInt()}")
                     }
                     is DirectMemoryRead -> {
                         if(arg2.addressExpression is NumericLiteralValue) {
@@ -223,9 +426,9 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                     is NumericLiteralValue -> {
                         asmgen.assignExpressionToRegister(arg1, RegisterOrPair.AY)
                         asmgen.out("""
-                            cpy  #>${arg2.number}
+                            cpy  #>${arg2.number.toInt()}
                             bne  +
-                            cmp  #<${arg2.number}
+                            cmp  #<${arg2.number.toInt()}
 +""")
                     }
                     else -> {
@@ -244,11 +447,12 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
     }
 
     private fun funcMemory(fcall: IFunctionCall, discardResult: Boolean, resultToStack: Boolean, resultRegister: RegisterOrPair?) {
-        if(discardResult || fcall !is FunctionCall)
+        if(discardResult || fcall !is FunctionCallExpression)
             throw AssemblyError("should not discard result of memory allocation at $fcall")
         val nameRef = fcall.args[0] as IdentifierReference
         val name = (nameRef.targetVarDecl(program)!!.value as StringLiteralValue).value
-        val size = (fcall.args[1] as NumericLiteralValue).number.toInt()
+        require(name.all { it.isLetterOrDigit() || it=='_' }) {"memory name should be a valid symbol name"}
+        val size = (fcall.args[1] as NumericLiteralValue).number.toUInt()
 
         val existingSize = asmgen.slabs[name]
         if(existingSize!=null && existingSize!=size)
@@ -261,7 +465,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
             if(resultToStack)
                 AsmAssignTarget(TargetStorageKind.STACK, program, asmgen, DataType.UWORD, null)
             else
-                AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.AY, null, program, asmgen)
+                AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.AY, false, null, program, asmgen)
         val assign = AsmAssignment(src, target, false, program.memsizer, fcall.position)
         asmgen.translateNormalAssignment(assign)
         asmgen.slabs[name] = size
@@ -273,7 +477,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
             asmgen.out("  jsr  prog8_lib.func_sqrt16_stack")
         else {
             asmgen.out("  jsr  prog8_lib.func_sqrt16_into_A")
-            assignAsmGen.assignRegisterByte(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.A, scope, program, asmgen), CpuRegister.A)
+            assignAsmGen.assignRegisterByte(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.A, false, scope, program, asmgen), CpuRegister.A)
         }
     }
 
@@ -283,13 +487,13 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
             asmgen.out("  jsr  prog8_lib.func_${func.name}_stack")
         else
             when(func.name) {
-                "sin8", "sin8u", "cos8", "cos8u" -> {
+                "sin8", "sin8u", "sinr8", "sinr8u", "cos8", "cos8u", "cosr8", "cosr8u" -> {
                     asmgen.out("  jsr  prog8_lib.func_${func.name}_into_A")
-                    assignAsmGen.assignRegisterByte(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.A, scope, program, asmgen), CpuRegister.A)
+                    assignAsmGen.assignRegisterByte(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.A, false, scope, program, asmgen), CpuRegister.A)
                 }
-                "sin16", "sin16u", "cos16", "cos16u" -> {
+                "sin16", "sin16u", "sinr16", "sinr16u", "cos16", "cos16u", "cosr16", "cosr16u" -> {
                     asmgen.out("  jsr  prog8_lib.func_${func.name}_into_AY")
-                    assignAsmGen.assignRegisterpairWord(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.AY, scope, program, asmgen), RegisterOrPair.AY)
+                    assignAsmGen.assignRegisterpairWord(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.AY, false, scope, program, asmgen), RegisterOrPair.AY)
                 }
             }
     }
@@ -578,7 +782,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
             asmgen.out("  jsr  floats.func_${func.name}_stack")
         else {
             asmgen.out("  jsr  floats.func_${func.name}_fac1")
-            assignAsmGen.assignFAC1float(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.FAC1, scope, program, asmgen))
+            assignAsmGen.assignFAC1float(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.FAC1, true, scope, program, asmgen))
         }
     }
 
@@ -603,7 +807,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                 DataType.FLOAT -> asmgen.out("  jsr  floats.func_sign_f_into_A")
                 else -> throw AssemblyError("weird type $dt")
             }
-            assignAsmGen.assignRegisterByte(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.A, scope, program, asmgen), CpuRegister.A)
+            assignAsmGen.assignRegisterByte(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.A, false, scope, program, asmgen), CpuRegister.A)
         }
     }
 
@@ -624,7 +828,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                 DataType.ARRAY_F -> asmgen.out("  jsr  floats.func_${function.name}_f_into_A")
                 else -> throw AssemblyError("weird type $dt")
             }
-            assignAsmGen.assignRegisterByte(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.A, scope, program, asmgen), CpuRegister.A)
+            assignAsmGen.assignRegisterByte(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.A, false, scope, program, asmgen), CpuRegister.A)
         }
     }
 
@@ -644,23 +848,23 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
             when (dt.getOr(DataType.UNDEFINED)) {
                 DataType.ARRAY_UB, DataType.STR -> {
                     asmgen.out("  jsr  prog8_lib.func_${function.name}_ub_into_A")
-                    assignAsmGen.assignRegisterByte(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.A, scope, program, asmgen), CpuRegister.A)
+                    assignAsmGen.assignRegisterByte(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.A, false, scope, program, asmgen), CpuRegister.A)
                 }
                 DataType.ARRAY_B -> {
                     asmgen.out("  jsr  prog8_lib.func_${function.name}_b_into_A")
-                    assignAsmGen.assignRegisterByte(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.A, scope, program, asmgen), CpuRegister.A)
+                    assignAsmGen.assignRegisterByte(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.A, false, scope, program, asmgen), CpuRegister.A)
                 }
                 DataType.ARRAY_UW -> {
                     asmgen.out("  jsr  prog8_lib.func_${function.name}_uw_into_AY")
-                    assignAsmGen.assignRegisterpairWord(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.AY, scope, program, asmgen), RegisterOrPair.AY)
+                    assignAsmGen.assignRegisterpairWord(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.AY, false, scope, program, asmgen), RegisterOrPair.AY)
                 }
                 DataType.ARRAY_W -> {
                     asmgen.out("  jsr  prog8_lib.func_${function.name}_w_into_AY")
-                    assignAsmGen.assignRegisterpairWord(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.AY, scope, program, asmgen), RegisterOrPair.AY)
+                    assignAsmGen.assignRegisterpairWord(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.AY, false, scope, program, asmgen), RegisterOrPair.AY)
                 }
                 DataType.ARRAY_F -> {
                     asmgen.out("  jsr  floats.func_${function.name}_f_fac1")
-                    assignAsmGen.assignFAC1float(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.FAC1, scope, program, asmgen))
+                    assignAsmGen.assignFAC1float(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.FAC1, true, scope, program, asmgen))
                 }
                 else -> throw AssemblyError("weird type $dt")
             }
@@ -683,23 +887,23 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
             when (dt.getOr(DataType.UNDEFINED)) {
                 DataType.ARRAY_UB, DataType.STR -> {
                     asmgen.out("  jsr  prog8_lib.func_sum_ub_into_AY")
-                    assignAsmGen.assignRegisterpairWord(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.AY, scope, program, asmgen), RegisterOrPair.AY)
+                    assignAsmGen.assignRegisterpairWord(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.AY, false, scope, program, asmgen), RegisterOrPair.AY)
                 }
                 DataType.ARRAY_B -> {
                     asmgen.out("  jsr  prog8_lib.func_sum_b_into_AY")
-                    assignAsmGen.assignRegisterpairWord(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.AY, scope, program, asmgen), RegisterOrPair.AY)
+                    assignAsmGen.assignRegisterpairWord(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.AY, false, scope, program, asmgen), RegisterOrPair.AY)
                 }
                 DataType.ARRAY_UW -> {
                     asmgen.out("  jsr  prog8_lib.func_sum_uw_into_AY")
-                    assignAsmGen.assignRegisterpairWord(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.AY, scope, program, asmgen), RegisterOrPair.AY)
+                    assignAsmGen.assignRegisterpairWord(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.AY, false, scope, program, asmgen), RegisterOrPair.AY)
                 }
                 DataType.ARRAY_W -> {
                     asmgen.out("  jsr  prog8_lib.func_sum_w_into_AY")
-                    assignAsmGen.assignRegisterpairWord(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.AY, scope, program, asmgen), RegisterOrPair.AY)
+                    assignAsmGen.assignRegisterpairWord(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.AY, false, scope, program, asmgen), RegisterOrPair.AY)
                 }
                 DataType.ARRAY_F -> {
                     asmgen.out("  jsr  floats.func_sum_f_fac1")
-                    assignAsmGen.assignFAC1float(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.FAC1, scope, program, asmgen))
+                    assignAsmGen.assignFAC1float(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.FAC1, true, scope, program, asmgen))
                 }
                 else -> throw AssemblyError("weird type $dt")
             }
@@ -785,7 +989,6 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                             && (firstOffset is NumericLiteralValue || firstOffset is IdentifierReference || firstOffset is TypecastExpression)
                             && (secondOffset is NumericLiteralValue || secondOffset is IdentifierReference || secondOffset is TypecastExpression)
                         ) {
-                            val pointerVar = firstExpr.left as IdentifierReference
                             if(firstOffset is NumericLiteralValue && secondOffset is NumericLiteralValue) {
                                 if(firstOffset!=secondOffset) {
                                     swapArrayValues(
@@ -823,9 +1026,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
             val arrayVarName1 = asmgen.asmVariableName(first.arrayvar)
             val arrayVarName2 = asmgen.asmVariableName(second.arrayvar)
             val elementIDt = first.inferType(program)
-            if(!elementIDt.isKnown)
-                throw AssemblyError("unknown dt")
-            val elementDt = elementIDt.getOr(DataType.UNDEFINED)
+            val elementDt = elementIDt.getOrElse { throw AssemblyError("unknown dt") }
 
             val firstNum = first.indexer.indexExpr as? NumericLiteralValue
             val firstVar = first.indexer.indexExpr as? IdentifierReference
@@ -876,21 +1077,23 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                 asmgen.translateNormalAssignment(assignSecond)
             }
             DataType.FLOAT -> {
-                // via evaluation stack
-                asmgen.translateExpression(first)
-                asmgen.translateExpression(second)
-                val assignFirst = AsmAssignment(
-                        AsmAssignSource(SourceStorageKind.STACK, program, asmgen, DataType.FLOAT),
+                // via temp variable and FAC1
+                asmgen.assignExpressionTo(first, AsmAssignTarget(TargetStorageKind.VARIABLE, program, asmgen, DataType.FLOAT, first.definingSubroutine, "floats.tempvar_swap_float"))
+                asmgen.assignExpressionTo(second, AsmAssignTarget(TargetStorageKind.REGISTER, program, asmgen, DataType.FLOAT, null, register=RegisterOrPair.FAC1))
+                asmgen.translateNormalAssignment(
+                    AsmAssignment(
+                        AsmAssignSource(SourceStorageKind.REGISTER, program, asmgen, datatype, register = RegisterOrPair.FAC1),
                         targetFromExpr(first, datatype),
                         false, program.memsizer, first.position
+                    )
                 )
-                val assignSecond = AsmAssignment(
-                        AsmAssignSource(SourceStorageKind.STACK, program, asmgen, DataType.FLOAT),
+                asmgen.translateNormalAssignment(
+                    AsmAssignment(
+                        AsmAssignSource(SourceStorageKind.VARIABLE, program, asmgen, datatype, "floats.tempvar_swap_float"),
                         targetFromExpr(second, datatype),
                         false, program.memsizer, second.position
+                    )
                 )
-                asmgen.translateNormalAssignment(assignFirst)
-                asmgen.translateNormalAssignment(assignSecond)
             }
             else -> throw AssemblyError("weird swap dt")
         }
@@ -1140,15 +1343,15 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
             when (dt) {
                 in ByteDatatypes -> {
                     asmgen.out("  jsr  prog8_lib.abs_b_into_A")
-                    assignAsmGen.assignRegisterByte(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.A, scope, program, asmgen), CpuRegister.A)
+                    assignAsmGen.assignRegisterByte(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.A, false, scope, program, asmgen), CpuRegister.A)
                 }
                 in WordDatatypes -> {
                     asmgen.out("  jsr  prog8_lib.abs_w_into_AY")
-                    assignAsmGen.assignRegisterpairWord(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.AY, scope, program, asmgen), RegisterOrPair.AY)
+                    assignAsmGen.assignRegisterpairWord(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.AY, false, scope, program, asmgen), RegisterOrPair.AY)
                 }
                 DataType.FLOAT -> {
                     asmgen.out("  jsr  floats.abs_f_fac1")
-                    assignAsmGen.assignFAC1float(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.FAC1, scope, program, asmgen))
+                    assignAsmGen.assignFAC1float(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.FAC1, true, scope, program, asmgen))
                 }
                 else -> throw AssemblyError("weird type")
             }
@@ -1162,7 +1365,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                     asmgen.out("  jsr  prog8_lib.func_rnd_stack")
                 else {
                     asmgen.out("  jsr  math.randbyte")
-                    assignAsmGen.assignRegisterByte(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.A, scope, program, asmgen), CpuRegister.A)
+                    assignAsmGen.assignRegisterByte(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.A, false, scope, program, asmgen), CpuRegister.A)
                 }
             }
             "rndw" -> {
@@ -1170,7 +1373,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                     asmgen.out("  jsr  prog8_lib.func_rndw_stack")
                 else {
                     asmgen.out("  jsr  math.randword")
-                    assignAsmGen.assignRegisterpairWord(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.AY, scope, program, asmgen), RegisterOrPair.AY)
+                    assignAsmGen.assignRegisterpairWord(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.AY, false, scope, program, asmgen), RegisterOrPair.AY)
                 }
             }
             else -> throw AssemblyError("wrong func")
@@ -1228,6 +1431,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                     }
                 }
             }
+            else -> throw AssemblyError("wrong pokew arg type")
         }
 
         asmgen.assignExpressionToVariable(fcall.args[0], "P8ZP_SCRATCH_W1", DataType.UWORD, null)
@@ -1474,7 +1678,9 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
     }
 
     private fun translateArguments(args: MutableList<Expression>, signature: FSignature, scope: Subroutine?) {
-        val callConv = signature.callConvention(args.map { it.inferType(program).getOr(DataType.UNDEFINED) })
+        val callConv = signature.callConvention(args.map {
+            it.inferType(program).getOrElse { throw AssemblyError("unknown dt")}
+        })
 
         fun getSourceForFloat(value: Expression): AsmAssignSource {
             return when (value) {
@@ -1533,7 +1739,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                             AsmAssignSource.fromAstSource(value, program, asmgen)
                         }
                     }
-                    val tgt = AsmAssignTarget.fromRegisters(conv.reg, null, program, asmgen)
+                    val tgt = AsmAssignTarget.fromRegisters(conv.reg!!, false, null, program, asmgen)
                     val assign = AsmAssignment(src, tgt, false, program.memsizer, value.position)
                     asmgen.translateNormalAssignment(assign)
                 }

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

@@ -1,15 +1,15 @@
-package prog8.compiler.target.cpu6502.codegen
+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.RangeExpr
+import prog8.ast.expressions.RangeExpression
 import prog8.ast.statements.ForLoop
 import prog8.ast.toHex
-import prog8.compiler.AssemblyError
-import prog8.compiler.astprocessing.toConstantIntegerRange
+import prog8.codegen.target.AssemblyError
 import kotlin.math.absoluteValue
 
 internal class ForLoopsAsmGen(private val program: Program, private val asmgen: AsmGen) {
@@ -19,22 +19,22 @@ internal class ForLoopsAsmGen(private val program: Program, private val asmgen:
         if(!iterableDt.isKnown)
             throw AssemblyError("unknown dt")
         when(stmt.iterable) {
-            is RangeExpr -> {
-                val range = (stmt.iterable as RangeExpr).toConstantIntegerRange(asmgen.options.compTarget)
+            is RangeExpression -> {
+                val range = (stmt.iterable as RangeExpression).toConstantIntegerRange()
                 if(range==null) {
-                    translateForOverNonconstRange(stmt, iterableDt.getOr(DataType.UNDEFINED), stmt.iterable as RangeExpr)
+                    translateForOverNonconstRange(stmt, iterableDt.getOrElse { throw AssemblyError("unknown dt") }, stmt.iterable as RangeExpression)
                 } else {
-                    translateForOverConstRange(stmt, iterableDt.getOr(DataType.UNDEFINED), range)
+                    translateForOverConstRange(stmt, iterableDt.getOrElse { throw AssemblyError("unknown dt") }, range)
                 }
             }
             is IdentifierReference -> {
-                translateForOverIterableVar(stmt, iterableDt.getOr(DataType.UNDEFINED), stmt.iterable as IdentifierReference)
+                translateForOverIterableVar(stmt, iterableDt.getOrElse { throw AssemblyError("unknown dt") }, stmt.iterable as IdentifierReference)
             }
             else -> throw AssemblyError("can't iterate over ${stmt.iterable.javaClass} - should have been replaced by a variable")
         }
     }
 
-    private fun translateForOverNonconstRange(stmt: ForLoop, iterableDt: DataType, range: RangeExpr) {
+    private fun translateForOverNonconstRange(stmt: ForLoop, iterableDt: DataType, range: RangeExpression) {
         val loopLabel = asmgen.makeLabel("for_loop")
         val endLabel = asmgen.makeLabel("for_end")
         val modifiedLabel = asmgen.makeLabel("for_modified")
@@ -43,7 +43,7 @@ internal class ForLoopsAsmGen(private val program: Program, private val asmgen:
         val stepsize=range.step.constValue(program)!!.number.toInt()
 
         if(stepsize < -1) {
-            val limit = range.to.constValue(program)?.number?.toDouble()
+            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")
         }
@@ -289,13 +289,15 @@ $loopLabel          sty  $indexVar
                         bne  $loopLabel
                         beq  $endLabel""")
                 }
-                if(length>=16 && asmgen.zeropage.hasByteAvailable()) {
-                    // allocate index var on ZP
-                    val zpAddr = asmgen.zeropage.allocate(indexVar, DataType.UBYTE, stmt.position, asmgen.errors)
-                    asmgen.out("""$indexVar = $zpAddr  ; auto zp UBYTE""")
+                if(length>=16) {
+                    // allocate index var on ZP if possible
+                    val result = asmgen.zeropage.allocate(listOf(indexVar), DataType.UBYTE, null, stmt.position, asmgen.errors)
+                    result.fold(
+                        success = { (address,_)-> asmgen.out("""$indexVar = $address  ; auto zp UBYTE""") },
+                        failure = { asmgen.out("$indexVar    .byte  0") }
+                    )
                 } else {
-                    asmgen.out("""
-$indexVar           .byte  0""")
+                    asmgen.out("$indexVar    .byte  0")
                 }
                 asmgen.out(endLabel)
             }
@@ -328,13 +330,15 @@ $loopLabel          sty  $indexVar
                         bne  $loopLabel
                         beq  $endLabel""")
                 }
-                if(length>=16 && asmgen.zeropage.hasByteAvailable()) {
-                    // allocate index var on ZP
-                    val zpAddr = asmgen.zeropage.allocate(indexVar, DataType.UBYTE, stmt.position, asmgen.errors)
-                    asmgen.out("""$indexVar = $zpAddr  ; auto zp UBYTE""")
+                if(length>=16) {
+                    // allocate index var on ZP if possible
+                    val result = asmgen.zeropage.allocate(listOf(indexVar), DataType.UBYTE, null, stmt.position, asmgen.errors)
+                    result.fold(
+                        success = { (address,_)-> asmgen.out("""$indexVar = $address  ; auto zp UBYTE""") },
+                        failure = { asmgen.out("$indexVar    .byte  0") }
+                    )
                 } else {
-                    asmgen.out("""
-$indexVar           .byte  0""")
+                    asmgen.out("$indexVar    .byte  0")
                 }
                 asmgen.out(endLabel)
             }
@@ -588,6 +592,10 @@ $loopLabel""")
         asmgen.loopEndLabels.pop()
     }
 
-    private fun assignLoopvar(stmt: ForLoop, range: RangeExpr) =
-        asmgen.assignExpressionToVariable(range.from, asmgen.asmVariableName(stmt.loopVar), stmt.loopVarDt(program).getOr(DataType.UNDEFINED), stmt.definingSubroutine)
+    private fun assignLoopvar(stmt: ForLoop, range: RangeExpression) =
+        asmgen.assignExpressionToVariable(
+            range.from,
+            asmgen.asmVariableName(stmt.loopVar),
+            stmt.loopVarDt(program).getOrElse { throw AssemblyError("unknown dt") },
+            stmt.definingSubroutine)
 }

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

@@ -1,27 +1,27 @@
-package prog8.compiler.target.cpu6502.codegen
+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.*
-import prog8.ast.statements.InlineAssembly
-import prog8.ast.statements.RegisterOrStatusflag
-import prog8.ast.statements.Subroutine
-import prog8.ast.statements.SubroutineParameter
-import prog8.compiler.AssemblyError
-import prog8.compiler.target.CpuType
-import prog8.compiler.target.cpu6502.codegen.assignment.AsmAssignSource
-import prog8.compiler.target.cpu6502.codegen.assignment.AsmAssignTarget
-import prog8.compiler.target.cpu6502.codegen.assignment.AsmAssignment
-import prog8.compiler.target.cpu6502.codegen.assignment.TargetStorageKind
+import prog8.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)
+        translateFunctionCall(stmt, false)
         restoreXafterCall(stmt)
         // just ignore any result values from the function call.
     }
@@ -37,6 +37,17 @@ internal class FunctionCallAsmGen(private val program: Program, private val asmg
         }
     }
 
+    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()) {
@@ -48,101 +59,177 @@ internal class FunctionCallAsmGen(private val program: Program, private val asmg
         }
     }
 
-    internal fun translateFunctionCall(stmt: IFunctionCall) {
+    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 = stmt.target.targetSubroutine(program) ?: throw AssemblyError("undefined subroutine ${stmt.target}")
-        val subName = asmgen.asmSymbolName(stmt.target)
-        if(stmt.args.isNotEmpty()) {
+        val sub = call.target.targetSubroutine(program) ?: throw AssemblyError("undefined subroutine ${call.target}")
+        val subAsmName = asmgen.asmSymbolName(call.target)
 
-            if(sub.asmParameterRegisters.isEmpty()) {
-                // via variables
-                for(arg in sub.parameters.withIndex().zip(stmt.args)) {
-                    argumentViaVariable(sub, arg.first, arg.second)
-                }
-            } else {
-                // via registers
-                if(sub.parameters.size==1) {
-                    // just a single parameter, no risk of clobbering registers
-                    argumentViaRegister(sub, IndexedValue(0, sub.parameters.single()), stmt.args[0])
-                } else {
-
-                    fun isNoClobberRisk(expr: Expression): Boolean {
-                        if(expr is AddressOf ||
-                                expr is NumericLiteralValue ||
-                                expr is StringLiteralValue ||
-                                expr is ArrayLiteralValue ||
-                                expr is IdentifierReference)
-                            return true
-
-                        if(expr is FunctionCall) {
-                            if(expr.target.nameInSource==listOf("lsb") || expr.target.nameInSource==listOf("msb"))
-                                return isNoClobberRisk(expr.args[0])
-                            if(expr.target.nameInSource==listOf("mkword"))
-                                return isNoClobberRisk(expr.args[0]) && isNoClobberRisk(expr.args[1])
-                        }
-
-                        return false
-                    }
-
-                    when {
-                        stmt.args.all {isNoClobberRisk(it)} -> {
-                            // There's no risk of clobbering for these simple argument types. Optimize the register loading directly from these values.
-                            // register assignment order: 1) cx16 virtual word registers, 2) actual CPU registers, 3) CPU Carry status flag.
-                            val argsInfo = sub.parameters.withIndex().zip(stmt.args).zip(sub.asmParameterRegisters)
-                            val (cx16virtualRegs, args2) = argsInfo.partition { it.second.registerOrPair in Cx16VirtualRegisters }
-                            val (cpuRegs, statusRegs) = args2.partition { it.second.registerOrPair!=null }
-                            for(arg in cx16virtualRegs)
-                                argumentViaRegister(sub, arg.first.first, arg.first.second)
-                            for(arg in cpuRegs)
-                                argumentViaRegister(sub, arg.first.first, arg.first.second)
-                            for(arg in statusRegs)
-                                argumentViaRegister(sub, arg.first.first, arg.first.second)
-                        }
-                        else -> {
-                            // Risk of clobbering due to complex expression args. Evaluate first, then assign registers.
-                            registerArgsViaStackEvaluation(stmt, sub)
-                        }
-                    }
-                }
-            }
+        if(!isExpression && !sub.isAsmSubroutine) {
+            if(!optimizeIntArgsViaRegisters(sub))
+                throw AssemblyError("functioncall statements to non-asmsub should have been replaced by GoSub $call")
         }
 
-        if(!sub.inline || !asmgen.options.optimize) {
-            asmgen.out("  jsr  $subName")
-        } else {
-            // 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)
-
-            // note: for now, this is only reliably supported for asmsubs.
-            if(!sub.isAsmSubroutine)
+        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")
 
-            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}")
+            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
@@ -209,11 +296,10 @@ internal class FunctionCallAsmGen(private val program: Program, private val asmg
         if(argForCarry!=null) {
             val plusIdxStr = if(argForCarry.index==0) "" else "+${argForCarry.index}"
             asmgen.out("""
+                clc
                 lda  P8ESTACK_LO$plusIdxStr,x
                 beq  +
                 sec
-                bcs  ++
-+               clc
 +               php""")             // push the status flags
         }
 
@@ -247,29 +333,25 @@ internal class FunctionCallAsmGen(private val program: Program, private val asmg
             asmgen.out("  plp")       // set the carry flag back to correct value
     }
 
-    private fun argumentViaVariable(sub: Subroutine, parameter: IndexedValue<SubroutineParameter>, value: Expression) {
+    private fun argumentViaVariable(sub: Subroutine, parameter: SubroutineParameter, value: Expression) {
         // pass parameter via a regular variable (not via registers)
         val valueIDt = value.inferType(program)
-        if(!valueIDt.isKnown)
-            throw AssemblyError("unknown dt")
-        val valueDt = valueIDt.getOr(DataType.UNDEFINED)
-        if(!isArgumentTypeCompatible(valueDt, parameter.value.type))
+        val valueDt = valueIDt.getOrElse { throw AssemblyError("unknown dt") }
+        if(!isArgumentTypeCompatible(valueDt, parameter.type))
             throw AssemblyError("argument type incompatible")
 
-        val varName = asmgen.asmVariableName(sub.scopedname+"."+parameter.value.name)
-        asmgen.assignExpressionToVariable(value, varName, parameter.value.type, sub)
+        val varName = asmgen.asmVariableName(sub.scopedName + parameter.name)
+        asmgen.assignExpressionToVariable(value, varName, parameter.type, sub)
     }
 
-    private fun argumentViaRegister(sub: Subroutine, parameter: IndexedValue<SubroutineParameter>, value: Expression) {
+    private fun argumentViaRegister(sub: Subroutine, parameter: IndexedValue<SubroutineParameter>, value: Expression, registerOverride: RegisterOrPair? = null) {
         // pass argument via a register parameter
         val valueIDt = value.inferType(program)
-        if(!valueIDt.isKnown)
-            throw AssemblyError("unknown dt")
-        val valueDt = valueIDt.getOr(DataType.UNDEFINED)
+        val valueDt = valueIDt.getOrElse { throw AssemblyError("unknown dt") }
         if(!isArgumentTypeCompatible(valueDt, parameter.value.type))
             throw AssemblyError("argument type incompatible")
 
-        val paramRegister = sub.asmParameterRegisters[parameter.index]
+        val paramRegister = if(registerOverride==null) sub.asmParameterRegisters[parameter.index] else RegisterOrStatusflag(registerOverride, null)
         val statusflag = paramRegister.statusflag
         val register = paramRegister.registerOrPair
         val requiredDt = parameter.value.type
@@ -291,23 +373,21 @@ internal class FunctionCallAsmGen(private val program: Program, private val asmg
                     is IdentifierReference -> {
                         val sourceName = asmgen.asmVariableName(value)
                         asmgen.out("""
-                pha
-                lda  $sourceName
-                beq  +
-                sec  
-                bcs  ++
-    +           clc
-    +           pla
-    """)
+                            pha
+                            clc
+                            lda  $sourceName
+                            beq  +
+                            sec  
++                           pla""")
                     }
                     else -> {
                         asmgen.assignExpressionToRegister(value, RegisterOrPair.A)
                         asmgen.out("""
-                                    beq  +
-                                    sec
-                                    bcs  ++
-    +                               clc
-    +""")
+                            beq  +
+                            sec
+                            bcs  ++
++                           clc
++""")
                     }
                 }
             } else throw AssemblyError("can only use Carry as status flag parameter")
@@ -324,8 +404,10 @@ internal class FunctionCallAsmGen(private val program: Program, private val asmg
                 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
-                        AsmAssignTarget.fromRegisters(register, sub, program, asmgen)
+                    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)

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

@@ -1,4 +1,4 @@
-package prog8.compiler.target.cpu6502.codegen
+package prog8.codegen.target.cpu6502.codegen
 
 import prog8.ast.Program
 import prog8.ast.base.*
@@ -6,7 +6,7 @@ import prog8.ast.expressions.IdentifierReference
 import prog8.ast.expressions.NumericLiteralValue
 import prog8.ast.statements.PostIncrDecr
 import prog8.ast.toHex
-import prog8.compiler.AssemblyError
+import prog8.codegen.target.AssemblyError
 
 
 internal class PostIncrDecrAsmGen(private val program: Program, private val asmgen: AsmGen) {
@@ -83,7 +83,7 @@ internal class PostIncrDecrAsmGen(private val program: Program, private val asmg
 """)
                         }
                         DataType.FLOAT -> {
-                            asmgen.out("  lda  #<$asmArrayvarname+$indexValue |  ldy  #>$asmArrayvarname+$indexValue")
+                            asmgen.out("  lda  #<($asmArrayvarname+$indexValue) |  ldy  #>($asmArrayvarname+$indexValue)")
                             asmgen.out(if(incr) "  jsr  floats.inc_var_f" else "  jsr  floats.dec_var_f")
                         }
                         else -> throw AssemblyError("need numeric type")

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

@@ -1,12 +1,12 @@
-package prog8.compiler.target.cpu6502.codegen.assignment
+package prog8.codegen.target.cpu6502.codegen.assignment
 
-import prog8.ast.IMemSizer
 import prog8.ast.Program
 import prog8.ast.base.*
 import prog8.ast.expressions.*
 import prog8.ast.statements.*
-import prog8.compiler.AssemblyError
-import prog8.compiler.target.cpu6502.codegen.AsmGen
+import prog8.compilerinterface.IMemSizer
+import prog8.codegen.target.AssemblyError
+import prog8.codegen.target.cpu6502.codegen.AsmGen
 
 
 internal enum class TargetStorageKind {
@@ -39,13 +39,14 @@ internal class AsmAssignTarget(val kind: TargetStorageKind,
                                val origAstTarget: AssignTarget? = null
                                )
 {
-    val constMemoryAddress by lazy { memory?.addressExpression?.constValue(program)?.number?.toInt() ?: 0}
-    val constArrayIndexValue by lazy { array?.indexer?.constIndex() }
-    val asmVarname: String
-        get() = if(array==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
 
@@ -55,27 +56,40 @@ internal class AsmAssignTarget(val kind: TargetStorageKind,
     }
 
     companion object {
-        fun fromAstAssignment(assign: Assignment, program: Program, asmgen: AsmGen): AsmAssignTarget = with(assign.target) {
-            val idt = inferType(program)
-            if(!idt.isKnown)
-                throw AssemblyError("unknown dt")
-            val dt = idt.getOr(DataType.UNDEFINED)
-            when {
-                identifier != null -> AsmAssignTarget(TargetStorageKind.VARIABLE, program, asmgen, dt, assign.definingSubroutine, variableAsmName = asmgen.asmVariableName(identifier!!), origAstTarget =  this)
-                arrayindexed != null -> AsmAssignTarget(TargetStorageKind.ARRAY, program, asmgen, dt, assign.definingSubroutine, array = arrayindexed, origAstTarget =  this)
-                memoryAddress != null -> AsmAssignTarget(TargetStorageKind.MEMORY, program, asmgen, dt, assign.definingSubroutine, memory =  memoryAddress, origAstTarget =  this)
-                else -> throw AssemblyError("weird target")
+        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, scope: Subroutine?, program: Program, asmgen: AsmGen): AsmAssignTarget =
+        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, DataType.UBYTE, scope, register = registers)
+                    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, DataType.UWORD, scope, register = registers)
+                    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,
@@ -93,7 +107,7 @@ internal class AsmAssignTarget(val kind: TargetStorageKind,
                     RegisterOrPair.R12,
                     RegisterOrPair.R13,
                     RegisterOrPair.R14,
-                    RegisterOrPair.R15 -> AsmAssignTarget(TargetStorageKind.REGISTER, program, asmgen, DataType.UWORD, scope, register = registers)
+                    RegisterOrPair.R15 -> AsmAssignTarget(TargetStorageKind.REGISTER, program, asmgen, if(signed) DataType.WORD else DataType.UWORD, scope, register = registers)
                 }
     }
 }
@@ -110,8 +124,8 @@ internal class AsmAssignSource(val kind: SourceStorageKind,
                                val expression: Expression? = null
 )
 {
-    val constMemoryAddress by lazy { memory?.addressExpression?.constValue(program)?.number?.toInt() ?: 0}
-    val constArrayIndexValue by lazy { array?.indexer?.constIndex() }
+    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)
@@ -128,10 +142,13 @@ internal class AsmAssignSource(val kind: SourceStorageKind,
                 return AsmAssignSource(SourceStorageKind.LITERALNUMBER, program, asmgen, cv.type, number = cv)
 
             return when(value) {
-                is NumericLiteralValue -> AsmAssignSource(SourceStorageKind.LITERALNUMBER, program, asmgen, value.type, number = cv)
+                is 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
@@ -147,10 +164,10 @@ internal class AsmAssignSource(val kind: SourceStorageKind,
                     AsmAssignSource(SourceStorageKind.MEMORY, program, asmgen, DataType.UBYTE, memory = value)
                 }
                 is ArrayIndexedExpression -> {
-                    val dt = value.inferType(program).getOr(DataType.UNDEFINED)
+                    val dt = value.inferType(program).getOrElse { throw AssemblyError("unknown dt") }
                     AsmAssignSource(SourceStorageKind.ARRAY, program, asmgen, dt, array = value)
                 }
-                is FunctionCall -> {
+                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
@@ -158,11 +175,9 @@ internal class AsmAssignSource(val kind: SourceStorageKind,
 
                             AsmAssignSource(SourceStorageKind.EXPRESSION, program, asmgen, returnType, expression = value)
                         }
-                        is BuiltinFunctionStatementPlaceholder -> {
+                        is BuiltinFunctionPlaceholder -> {
                             val returnType = value.inferType(program)
-                            if(!returnType.isKnown)
-                                throw AssemblyError("unknown dt")
-                            AsmAssignSource(SourceStorageKind.EXPRESSION, program, asmgen, returnType.getOr(DataType.UNDEFINED), expression = value)
+                            AsmAssignSource(SourceStorageKind.EXPRESSION, program, asmgen, returnType.getOrElse { throw AssemblyError("unknown dt") }, expression = value)
                         }
                         else -> {
                             throw AssemblyError("weird call")
@@ -171,9 +186,7 @@ internal class AsmAssignSource(val kind: SourceStorageKind,
                 }
                 else -> {
                     val dt = value.inferType(program)
-                    if(!dt.isKnown)
-                        throw AssemblyError("unknown dt")
-                    AsmAssignSource(SourceStorageKind.EXPRESSION, program, asmgen, dt.getOr(DataType.UNDEFINED), expression = value)
+                    AsmAssignSource(SourceStorageKind.EXPRESSION, program, asmgen, dt.getOrElse { throw AssemblyError("unknown dt") }, expression = value)
                 }
             }
         }
@@ -208,7 +221,7 @@ internal class AsmAssignment(val source: AsmAssignSource,
         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 storage size must be less or equal to target datatype storage size"
+                "source dt size must be less or equal to target dt size at $position"
             }
     }
 }

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

@@ -1,23 +1,20 @@
-package prog8.compiler.target.cpu6502.codegen.assignment
+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.ast.toHex
-import prog8.compiler.AssemblyError
-import prog8.compiler.functions.BuiltinFunctions
-import prog8.compiler.functions.builtinFunctionReturnType
-import prog8.compiler.target.CpuType
-import prog8.compiler.target.cpu6502.codegen.AsmGen
-import prog8.compiler.target.cpu6502.codegen.ExpressionsAsmGen
+import prog8.codegen.target.AssemblyError
+import prog8.codegen.target.cpu6502.codegen.AsmGen
+import prog8.compilerinterface.BuiltinFunctions
+import prog8.compilerinterface.CpuType
+import prog8.compilerinterface.builtinFunctionReturnType
 
 
-internal class AssignmentAsmGen(private val program: Program, private val asmgen: AsmGen,
-                                private val exprAsmgen: ExpressionsAsmGen
-) {
+internal class AssignmentAsmGen(private val program: Program, private val asmgen: AsmGen) {
 
-    private val augmentableAsmGen = AugmentableAssignmentAsmGen(program, this, exprAsmgen, asmgen)
+    private val augmentableAsmGen = AugmentableAssignmentAsmGen(program, this, asmgen)
 
     fun translate(assignment: Assignment) {
         val target = AsmAssignTarget.fromAstAssignment(assignment, program, asmgen)
@@ -32,15 +29,27 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
             translateNormalAssignment(assign)
     }
 
+    internal fun virtualRegsToVariables(origtarget: AsmAssignTarget): AsmAssignTarget {
+        return if(origtarget.kind==TargetStorageKind.REGISTER && origtarget.register in Cx16VirtualRegisters) {
+            AsmAssignTarget(TargetStorageKind.VARIABLE, program, asmgen, origtarget.datatype, origtarget.scope,
+                variableAsmName = "cx16.${origtarget.register!!.name.lowercase()}", origAstTarget = origtarget.origAstTarget)
+        } else origtarget
+    }
+
     fun translateNormalAssignment(assign: AsmAssignment) {
+        if(assign.isAugmentable) {
+            augmentableAsmGen.translate(assign)
+            return
+        }
+
         when(assign.source.kind) {
             SourceStorageKind.LITERALNUMBER -> {
                 // simple case: assign a constant number
                 val num = assign.source.number!!.number
                 when (assign.target.datatype) {
-                    DataType.UBYTE, DataType.BYTE -> assignConstantByte(assign.target, num.toShort())
+                    DataType.UBYTE, DataType.BYTE -> assignConstantByte(assign.target, num.toInt())
                     DataType.UWORD, DataType.WORD -> assignConstantWord(assign.target, num.toInt())
-                    DataType.FLOAT -> assignConstantFloat(assign.target, num.toDouble())
+                    DataType.FLOAT -> assignConstantFloat(assign.target, num)
                     else -> throw AssemblyError("weird numval type")
                 }
             }
@@ -79,7 +88,7 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                             assignRegisterpairWord(assign.target, RegisterOrPair.AY)
                         }
                         DataType.FLOAT -> {
-                            asmgen.out("  lda  #<$arrayVarName+$indexValue |  ldy  #>$arrayVarName+$indexValue")
+                            asmgen.out("  lda  #<($arrayVarName+$indexValue) |  ldy  #>($arrayVarName+$indexValue)")
                             assignFloatFromAY(assign.target)
                         }
                         else ->
@@ -116,17 +125,14 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
             SourceStorageKind.MEMORY -> {
                 fun assignViaExprEval(expression: Expression) {
                     assignExpressionToVariable(expression, "P8ZP_SCRATCH_W2", DataType.UWORD, assign.target.scope)
-                    if (asmgen.isTargetCpu(CpuType.CPU65c02))
-                        asmgen.out("  lda  (P8ZP_SCRATCH_W2)")
-                    else
-                        asmgen.out("  ldy  #0 |  lda  (P8ZP_SCRATCH_W2),y")
+                    asmgen.loadAFromZpPointerVar("P8ZP_SCRATCH_W2")
                     assignRegisterByte(assign.target, CpuRegister.A)
                 }
 
                 val value = assign.source.memory!!
                 when (value.addressExpression) {
                     is NumericLiteralValue -> {
-                        val address = (value.addressExpression as NumericLiteralValue).number.toInt()
+                        val address = (value.addressExpression as NumericLiteralValue).number.toUInt()
                         assignMemoryByte(assign.target, address, null)
                     }
                     is IdentifierReference -> {
@@ -153,11 +159,11 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                     is ArrayIndexedExpression -> throw AssemblyError("source kind should have been array")
                     is DirectMemoryRead -> throw AssemblyError("source kind should have been memory")
                     is TypecastExpression -> assignTypeCastedValue(assign.target, value.type, value.expression, value)
-                    is FunctionCall -> {
+                    is FunctionCallExpression -> {
                         when (val sub = value.target.targetStatement(program)) {
                             is Subroutine -> {
                                 asmgen.saveXbeforeCall(value)
-                                asmgen.translateFunctionCall(value)
+                                asmgen.translateFunctionCall(value, true)
                                 val returnValue = sub.returntypes.zip(sub.asmReturnvaluesRegisters).singleOrNull { it.second.registerOrPair!=null } ?:
                                     sub.returntypes.zip(sub.asmReturnvaluesRegisters).single { it.second.statusflag!=null }
                                 when (returnValue.first) {
@@ -171,13 +177,13 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                                             DataType.STR, DataType.ARRAY_UB, DataType.ARRAY_B -> {
                                                 // copy the actual string result into the target string variable
                                                 asmgen.out("""
-                                                                        pha
-                                                                        lda  #<${assign.target.asmVarname}
-                                                                        sta  P8ZP_SCRATCH_W1
-                                                                        lda  #>${assign.target.asmVarname}
-                                                                        sta  P8ZP_SCRATCH_W1+1
-                                                                        pla
-                                                                        jsr  prog8_lib.strcpy""")
+                                                    pha
+                                                    lda  #<${assign.target.asmVarname}
+                                                    sta  P8ZP_SCRATCH_W1
+                                                    lda  #>${assign.target.asmVarname}
+                                                    sta  P8ZP_SCRATCH_W1+1
+                                                    pla
+                                                    jsr  prog8_lib.strcpy""")
                                             }
                                             else -> throw AssemblyError("weird target dt")
                                         }
@@ -209,7 +215,7 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                                     }
                                 }
                             }
-                            is BuiltinFunctionStatementPlaceholder -> {
+                            is BuiltinFunctionPlaceholder -> {
                                 val signature = BuiltinFunctions.getValue(sub.name)
                                 asmgen.translateBuiltinFunctionCallExpression(value, signature, false, assign.target.register)
                                 if(assign.target.register==null) {
@@ -249,34 +255,212 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                             }
                         }
                     }
+                    is PrefixExpression -> {
+                        // first assign the value to the target then apply the operator in place on the target.
+                        translateNormalAssignment(AsmAssignment(
+                            AsmAssignSource.fromAstSource(value.expression, program, asmgen),
+                            assign.target,
+                            false, program.memsizer, assign.position
+                        ))
+                        val target = virtualRegsToVariables(assign.target)
+                        when(value.operator) {
+                            "+" -> {}
+                            "-" -> augmentableAsmGen.inplaceNegate(target, target.datatype)
+                            "~" -> augmentableAsmGen.inplaceInvert(target, target.datatype)
+                            "not" -> augmentableAsmGen.inplaceBooleanNot(target, target.datatype)
+                            else -> throw AssemblyError("invalid prefix operator")
+                        }
+                    }
+                    is ContainmentCheck -> {
+                        containmentCheckIntoA(value)
+                        assignRegisterByte(assign.target, CpuRegister.A)
+                    }
+                    is PipeExpression -> {
+                        asmgen.translatePipeExpression(value.expressions, value, false, false)
+                        val resultDt = value.inferType(program)
+                        val register =
+                            if(resultDt.isBytes) RegisterOrPair.A
+                            else if(resultDt.isWords) RegisterOrPair.AY
+                            else if(resultDt istype DataType.FLOAT) RegisterOrPair.FAC1
+                            else throw AssemblyError("invalid dt")
+                        asmgen.assignRegister(register, assign.target)
+                    }
+                    is BinaryExpression -> {
+                        if(value.operator in ComparisonOperators) {
+                            // TODO real optimized code for comparison expressions that yield a boolean result value
+                            // for now generate code for this:  assign-false; if expr { assign-true }
+                            translateNormalAssignment(
+                                AsmAssignment(
+                                    AsmAssignSource(SourceStorageKind.LITERALNUMBER, program, asmgen, DataType.UBYTE, number=NumericLiteralValue.fromBoolean(false, assign.position)),
+                                    assign.target, false, program.memsizer, assign.position
+                                )
+                            )
+                            val origTarget = assign.target.origAstTarget
+                            if(origTarget!=null) {
+                                val assignTrue = AnonymousScope(mutableListOf(
+                                    Assignment(origTarget, NumericLiteralValue.fromBoolean(true, assign.position), AssignmentOrigin.ASMGEN, assign.position)
+                                ), assign.position)
+                                val assignFalse = AnonymousScope(mutableListOf(), assign.position)
+                                val ifelse = IfElse(value.copy(), assignTrue, assignFalse, assign.position)
+                                ifelse.linkParents(value)
+                                asmgen.translate(ifelse)
+                            }
+                            else {
+                                // no orig ast assign target, can't use the workaround, so fallback to stack eval
+                                fallbackToStackEval(value, assign)
+                            }
+                        } else {
+                            // Everything else just evaluate via the stack.
+                            // (we can't use the assignment helper functions (assignExpressionTo...) to do it via registers here,
+                            // because the code here is the implementation of exactly that...)
+                            fallbackToStackEval(value, assign)
+                        }
+                    }
                     else -> {
                         // Everything else just evaluate via the stack.
-                        // (we can't use the assignment helper functions to do it via registers here,
+                        // (we can't use the assignment helper functions (assignExpressionTo...) to do it via registers here,
                         // because the code here is the implementation of exactly that...)
-                        if (value.parent is Return) {
-                            if (this.asmgen.options.slowCodegenWarnings)
-                                println("warning: slow stack evaluation used for return: $value  target=${assign.target.kind} at ${value.position}")
-                        }
-                        exprAsmgen.translateExpression(value)
-                        if (assign.target.datatype in WordDatatypes && assign.source.datatype in ByteDatatypes)
-                            asmgen.signExtendStackLsb(assign.source.datatype)
-                        assignStackValue(assign.target)
+                        fallbackToStackEval(value, assign)
                     }
                 }
             }
             SourceStorageKind.REGISTER -> {
-                when(assign.source.datatype) {
-                    DataType.UBYTE -> assignRegisterByte(assign.target, assign.source.register!!.asCpuRegister())
-                    DataType.UWORD -> assignRegisterpairWord(assign.target, assign.source.register!!)
-                    else -> throw AssemblyError("invalid register dt")
-                }
+                asmgen.assignRegister(assign.source.register!!, assign.target)
             }
             SourceStorageKind.STACK -> {
-                assignStackValue(assign.target)
+                if(assign.target.kind!=TargetStorageKind.STACK || assign.target.datatype != assign.source.datatype)
+                    assignStackValue(assign.target)
             }
         }
     }
 
+    private fun fallbackToStackEval(value: Expression, assign: AsmAssignment) {
+        // TODO DON'T STACK-EVAL THIS... by using a temp var? so that it becomes augmentable assignment expression?
+        asmgen.translateExpression(value)
+        if (assign.target.datatype in WordDatatypes && assign.source.datatype in ByteDatatypes)
+            asmgen.signExtendStackLsb(assign.source.datatype)
+        if (assign.target.kind != TargetStorageKind.STACK || assign.target.datatype != assign.source.datatype)
+            assignStackValue(assign.target)
+    }
+
+    private fun containmentCheckIntoA(containment: ContainmentCheck) {
+        val elementDt = containment.element.inferType(program)
+        val range = containment.iterable as? RangeExpression
+        if(range!=null) {
+            val constRange = range.toConstantIntegerRange()
+            if(constRange!=null)
+                return containmentCheckIntoA(containment.element, elementDt.getOr(DataType.UNDEFINED), constRange.toList())
+            TODO("non-const range containment check ${containment.position}")
+        }
+        val variable = (containment.iterable as? IdentifierReference)?.targetVarDecl(program)
+        if(variable!=null) {
+            if(elementDt istype DataType.FLOAT)
+                throw AssemblyError("containment check of floats not supported")
+            if(variable.origin!=VarDeclOrigin.USERCODE) {
+                when(variable.datatype) {
+                    DataType.STR -> {
+                        require(elementDt.isBytes)
+                        val stringVal = variable.value as StringLiteralValue
+                        val encoded = program.encoding.encodeString(stringVal.value, stringVal.encoding)
+                        return containmentCheckIntoA(containment.element, elementDt.getOr(DataType.UNDEFINED), encoded.map { it.toInt() })
+                    }
+                    DataType.ARRAY_F -> {
+                        // require(elementDt istype DataType.FLOAT)
+                        throw AssemblyError("containment check of floats not supported")
+                    }
+                    in ArrayDatatypes -> {
+                        require(elementDt.isInteger)
+                        val arrayVal = variable.value as ArrayLiteralValue
+                        val values = arrayVal.value.map { it.constValue(program)!!.number.toInt() }
+                        return containmentCheckIntoA(containment.element, elementDt.getOr(DataType.UNDEFINED), values)
+                    }
+                    else -> throw AssemblyError("invalid dt")
+                }
+            }
+            val varname = asmgen.asmVariableName(containment.iterable as IdentifierReference)
+            when(variable.datatype) {
+                DataType.STR -> {
+                    assignAddressOf(AsmAssignTarget(TargetStorageKind.VARIABLE, program, asmgen, DataType.UWORD, containment.definingSubroutine, "P8ZP_SCRATCH_W1"), varname)
+                    assignExpressionToRegister(containment.element, RegisterOrPair.A, elementDt istype DataType.BYTE)
+                    val stringVal = variable.value as StringLiteralValue
+                    asmgen.out("  ldy  #${stringVal.value.length}")
+                    asmgen.out("  jsr  prog8_lib.containment_bytearray")
+                    return
+                }
+                DataType.ARRAY_F -> throw AssemblyError("containment check of floats not supported")
+                DataType.ARRAY_B, DataType.ARRAY_UB -> {
+                    val arrayVal = variable.value as ArrayLiteralValue
+                    assignAddressOf(AsmAssignTarget(TargetStorageKind.VARIABLE, program, asmgen, DataType.UWORD, containment.definingSubroutine, "P8ZP_SCRATCH_W1"), varname)
+                    assignExpressionToRegister(containment.element, RegisterOrPair.A, elementDt istype DataType.BYTE)
+                    asmgen.out("  ldy  #${arrayVal.value.size}")
+                    asmgen.out("  jsr  prog8_lib.containment_bytearray")
+                    return
+                }
+                DataType.ARRAY_W, DataType.ARRAY_UW -> {
+                    val arrayVal = variable.value as ArrayLiteralValue
+                    assignExpressionToVariable(containment.element, "P8ZP_SCRATCH_W1", elementDt.getOr(DataType.UNDEFINED), containment.definingSubroutine)
+                    assignAddressOf(AsmAssignTarget(TargetStorageKind.VARIABLE, program, asmgen, DataType.UWORD, containment.definingSubroutine, "P8ZP_SCRATCH_W2"), varname)
+                    asmgen.out("  ldy  #${arrayVal.value.size}")
+                    asmgen.out("  jsr  prog8_lib.containment_wordarray")
+                    return
+                }
+                else -> throw AssemblyError("invalid dt")
+            }
+        }
+        val stringVal = containment.iterable as? StringLiteralValue
+        if(stringVal!=null) {
+            require(elementDt.isBytes)
+            val encoded = program.encoding.encodeString(stringVal.value, stringVal.encoding)
+            return containmentCheckIntoA(containment.element, elementDt.getOr(DataType.UNDEFINED), encoded.map { it.toInt() })
+        }
+        val arrayVal = containment.iterable as? ArrayLiteralValue
+        if(arrayVal!=null) {
+            require(elementDt.isInteger)
+            val values = arrayVal.value.map { it.constValue(program)!!.number.toInt() }
+            return containmentCheckIntoA(containment.element, elementDt.getOr(DataType.UNDEFINED), values)
+        }
+
+        throw AssemblyError("invalid containment iterable type")
+    }
+
+    private fun containmentCheckIntoA(element: Expression, dt: DataType, values: List<Number>) {
+        if(values.size<2)
+            throw AssemblyError("containment check against 0 or 1 values should have been optimized away")
+
+        // TODO don't generate a huge cmp-list when we go over a certain number of values
+        val containsLabel = asmgen.makeLabel("contains")
+        when(dt) {
+            in ByteDatatypes -> {
+                asmgen.assignExpressionToRegister(element, RegisterOrPair.A, dt==DataType.BYTE)
+                for (value in values) {
+                    asmgen.out("  cmp  #$value |  beq  +")
+                }
+                asmgen.out("""
+                    lda  #0
+                    beq  ++
++                   lda  #1
++""")
+            }
+            in WordDatatypes -> {
+                asmgen.assignExpressionToRegister(element, RegisterOrPair.AY, dt==DataType.WORD)
+                for (value in values) {
+                    asmgen.out("""
+                        cmp  #<$value
+                        bne  +
+                        cpy  #>$value
+                        beq  $containsLabel
++""")
+                }
+                asmgen.out("""
+                    lda  #0
+                    beq  +
+$containsLabel      lda  #1
++""")
+            }
+            else -> throw AssemblyError("invalid dt")
+        }
+    }
+
     private fun assignStatusFlagByte(target: AsmAssignTarget, statusflag: Statusflag) {
         when(statusflag) {
             Statusflag.Pc -> {
@@ -297,9 +481,7 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
 
     private fun assignTypeCastedValue(target: AsmAssignTarget, targetDt: DataType, value: Expression, origTypeCastExpression: TypecastExpression) {
         val valueIDt = value.inferType(program)
-        if(!valueIDt.isKnown)
-            throw AssemblyError("unknown dt")
-        val valueDt = valueIDt.getOr(DataType.UNDEFINED)
+        val valueDt = valueIDt.getOrElse { throw AssemblyError("unknown dt") }
         if(valueDt==targetDt)
             throw AssemblyError("type cast to identical dt should have been removed")
 
@@ -321,16 +503,13 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
 
                     fun assignViaExprEval(addressExpression: Expression) {
                         asmgen.assignExpressionToVariable(addressExpression, "P8ZP_SCRATCH_W2", DataType.UWORD, null)
-                        if (asmgen.isTargetCpu(CpuType.CPU65c02))
-                            asmgen.out("  lda  (P8ZP_SCRATCH_W2)")
-                        else
-                            asmgen.out("  ldy  #0 |  lda  (P8ZP_SCRATCH_W2),y")
+                        asmgen.loadAFromZpPointerVar("P8ZP_SCRATCH_W2")
                         assignRegisterByte(target, CpuRegister.A)
                     }
 
                     when (value.addressExpression) {
                         is NumericLiteralValue -> {
-                            val address = (value.addressExpression as NumericLiteralValue).number.toInt()
+                            val address = (value.addressExpression as NumericLiteralValue).number.toUInt()
                             assignMemoryByteIntoWord(target, address, null)
                             return
                         }
@@ -364,16 +543,16 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
 
             when (valueDt) {
                 in ByteDatatypes -> {
-                    assignExpressionToRegister(value, RegisterOrPair.A)
+                    assignExpressionToRegister(value, RegisterOrPair.A, valueDt==DataType.BYTE)
                     assignTypeCastedRegisters(target.asmVarname, targetDt, RegisterOrPair.A, valueDt)
                 }
                 in WordDatatypes -> {
-                    assignExpressionToRegister(value, RegisterOrPair.AY)
+                    assignExpressionToRegister(value, RegisterOrPair.AY, valueDt==DataType.WORD)
                     assignTypeCastedRegisters(target.asmVarname, targetDt, RegisterOrPair.AY, valueDt)
                 }
                 DataType.FLOAT -> {
-                    assignExpressionToRegister(value, RegisterOrPair.FAC1)
-                    assignTypecastedFloatFAC1(target.asmVarname, targetDt)
+                    assignExpressionToRegister(value, RegisterOrPair.FAC1, true)
+                    assignTypeCastedFloatFAC1(target.asmVarname, targetDt)
                 }
                 in PassByReferenceDatatypes -> {
                     // str/array value cast (most likely to UWORD, take address-of)
@@ -399,14 +578,14 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                 RegisterOrPair.X,
                 RegisterOrPair.Y -> {
                     // 'cast' an ubyte value to a byte register; no cast needed at all
-                    return assignExpressionToRegister(value, target.register)
+                    return assignExpressionToRegister(value, target.register, false)
                 }
                 RegisterOrPair.AX,
                 RegisterOrPair.AY,
                 RegisterOrPair.XY,
                 in Cx16VirtualRegisters -> {
                     // cast an ubyte value to a 16 bits register, just assign it and make use of the value extension
-                    return assignExpressionToRegister(value, target.register!!)
+                    return assignExpressionToRegister(value, target.register!!, false)
                 }
                 else -> {}
             }
@@ -424,30 +603,57 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                 RegisterOrPair.XY,
                 in Cx16VirtualRegisters -> {
                     // 'cast' uword into a 16 bits register, just assign it
-                    return assignExpressionToRegister(value, target.register!!)
+                    return assignExpressionToRegister(value, target.register!!, false)
                 }
                 else -> {}
             }
         }
 
-        // give up, do it via eval stack
-        // note: cannot use assignTypeCastedValue because that is ourselves :P
-        // TODO optimize typecasts for more special cases?
-        if(this.asmgen.options.slowCodegenWarnings)
-            println("warning: slow stack evaluation used for typecast: $value into $targetDt (target=${target.kind} at ${value.position}")
-        asmgen.translateExpression(origTypeCastExpression)      // this performs the actual type cast in translateExpression(Typecast)
-        assignStackValue(target)
+        if(target.kind==TargetStorageKind.REGISTER) {
+            assignExpressionToRegister(value, target.register!!, targetDt==DataType.BYTE || targetDt==DataType.WORD)
+            return
+        }
+
+        if(targetDt==DataType.FLOAT && (target.register==RegisterOrPair.FAC1 || target.register==RegisterOrPair.FAC2)) {
+            when(valueDt) {
+                DataType.UBYTE -> {
+                    assignExpressionToRegister(value, RegisterOrPair.Y, false)
+                    asmgen.out("  jsr  floats.FREADUY")
+                }
+                DataType.BYTE -> {
+                    assignExpressionToRegister(value, RegisterOrPair.A, true)
+                    asmgen.out("  jsr  floats.FREADSA")
+                }
+                DataType.UWORD -> {
+                    assignExpressionToRegister(value, RegisterOrPair.AY, false)
+                    asmgen.out("  jsr  floats.GIVUAYFAY")
+                }
+                DataType.WORD -> {
+                    assignExpressionToRegister(value, RegisterOrPair.AY, true)
+                    asmgen.out("  jsr  floats.GIVAYFAY")
+                }
+                else -> throw AssemblyError("invalid dt")
+            }
+            if(target.register==RegisterOrPair.FAC2) {
+                asmgen.out("  jsr floats.MOVEF")
+            }
+        } else {
+            // No more special optmized cases yet. Do the rest via more complex evaluation
+            // note: cannot use assignTypeCastedValue because that is ourselves :P
+            // NOTE: THIS MAY TURN INTO A STACK OVERFLOW ERROR IF IT CAN'T SIMPLIFY THE TYPECAST..... :-/
+            asmgen.assignExpressionTo(origTypeCastExpression, target)
+        }
     }
 
     private fun assignCastViaLsbFunc(value: Expression, target: AsmAssignTarget) {
-        val lsb = FunctionCall(IdentifierReference(listOf("lsb"), value.position), mutableListOf(value), value.position)
+        val lsb = FunctionCallExpression(IdentifierReference(listOf("lsb"), value.position), mutableListOf(value), value.position)
         lsb.linkParents(value.parent)
         val src = AsmAssignSource(SourceStorageKind.EXPRESSION, program, asmgen, DataType.UBYTE, expression = lsb)
         val assign = AsmAssignment(src, target, false, program.memsizer, value.position)
         translateNormalAssignment(assign)
     }
 
-    private fun assignTypecastedFloatFAC1(targetAsmVarName: String, targetDt: DataType) {
+    private fun assignTypeCastedFloatFAC1(targetAsmVarName: String, targetDt: DataType) {
 
         if(targetDt==DataType.FLOAT)
             throw AssemblyError("typecast to identical type")
@@ -768,7 +974,7 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
             }
             TargetStorageKind.ARRAY -> {
                 if(target.constArrayIndexValue!=null) {
-                    val scaledIdx = target.constArrayIndexValue!! * program.memsizer.memorySize(target.datatype)
+                    val scaledIdx = target.constArrayIndexValue!! * program.memsizer.memorySize(target.datatype).toUInt()
                     when(target.datatype) {
                         in ByteDatatypes -> {
                             asmgen.out(" inx | lda  P8ESTACK_LO,x  | sta  ${target.asmVarname}+$scaledIdx")
@@ -784,8 +990,8 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                         }
                         DataType.FLOAT -> {
                             asmgen.out("""
-                                lda  #<${target.asmVarname}+$scaledIdx
-                                ldy  #>${target.asmVarname}+$scaledIdx
+                                lda  #<(${target.asmVarname}+$scaledIdx)
+                                ldy  #>(${target.asmVarname}+$scaledIdx)
                                 jsr  floats.pop_float
                             """)
                         }
@@ -954,7 +1160,8 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                     lda  #<$sourceName
                     ldy  #>$sourceName+1
                     sta  P8ESTACK_LO,x
-                    sty  P8ESTACK_HI,x
+                    tya
+                    sta  P8ESTACK_HI,x
                     dex""")
             }
             else -> throw AssemblyError("string-assign to weird target")
@@ -977,7 +1184,7 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
             TargetStorageKind.ARRAY -> {
                 target.array!!
                 if(target.constArrayIndexValue!=null) {
-                    val scaledIdx = target.constArrayIndexValue!! * program.memsizer.memorySize(target.datatype)
+                    val scaledIdx = target.constArrayIndexValue!! * program.memsizer.memorySize(target.datatype).toUInt()
                     when(target.datatype) {
                         in ByteDatatypes -> {
                             asmgen.out(" lda  $sourceName  | sta  ${target.asmVarname}+$scaledIdx")
@@ -996,8 +1203,8 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                                 ldy  #>$sourceName
                                 sta  P8ZP_SCRATCH_W1
                                 sty  P8ZP_SCRATCH_W1+1
-                                lda  #<${target.asmVarname}+$scaledIdx
-                                ldy  #>${target.asmVarname}+$scaledIdx
+                                lda  #<(${target.asmVarname}+$scaledIdx)
+                                ldy  #>(${target.asmVarname}+$scaledIdx)
                                 jsr  floats.copy_float
                             """)
                         }
@@ -1032,7 +1239,7 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                                 adc  #<${target.asmVarname}
                                 bcc  +
                                 iny
-+                                   jsr  floats.copy_float""")
++                               jsr  floats.copy_float""")
                         }
                         else -> throw AssemblyError("weird dt")
                     }
@@ -1066,6 +1273,11 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
         }
     }
 
+    internal fun assignFAC2float(target: AsmAssignTarget) {
+        asmgen.out("  jsr  floats.MOVFA")       // fac2 -> fac1
+        assignFAC1float(target)
+    }
+
     internal fun assignFAC1float(target: AsmAssignTarget) {
         when(target.kind) {
             TargetStorageKind.VARIABLE -> {
@@ -1144,17 +1356,13 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
         when(target.kind) {
             TargetStorageKind.VARIABLE -> {
                 asmgen.out("""
-                    lda  $sourceName
-                    sta  ${target.asmVarname}
-                    lda  $sourceName+1
-                    sta  ${target.asmVarname}+1
-                    lda  $sourceName+2
-                    sta  ${target.asmVarname}+2
-                    lda  $sourceName+3
-                    sta  ${target.asmVarname}+3
-                    lda  $sourceName+4
-                    sta  ${target.asmVarname}+4
-                """)
+                    lda  #<$sourceName
+                    ldy  #>$sourceName
+                    sta  P8ZP_SCRATCH_W1
+                    sty  P8ZP_SCRATCH_W1+1
+                    lda  #<${target.asmVarname}
+                    ldy  #>${target.asmVarname}
+                    jsr  floats.copy_float""")
             }
             TargetStorageKind.ARRAY -> {
                 asmgen.out("""
@@ -1201,7 +1409,7 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
             }
             TargetStorageKind.ARRAY -> {
                 if (target.constArrayIndexValue!=null) {
-                    val scaledIdx = target.constArrayIndexValue!! * program.memsizer.memorySize(target.datatype)
+                    val scaledIdx = target.constArrayIndexValue!! * program.memsizer.memorySize(target.datatype).toUInt()
                     asmgen.out(" lda  $sourceName  | sta  ${target.asmVarname}+$scaledIdx")
                 }
                 else {
@@ -1254,7 +1462,7 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
             }
             TargetStorageKind.ARRAY -> {
                 if (wordtarget.constArrayIndexValue!=null) {
-                    val scaledIdx = wordtarget.constArrayIndexValue!! * 2
+                    val scaledIdx = wordtarget.constArrayIndexValue!! * 2u
                     asmgen.out("  lda  $sourceName")
                     asmgen.signExtendAYlsb(DataType.BYTE)
                     asmgen.out("  sta  ${wordtarget.asmVarname}+$scaledIdx |  sty  ${wordtarget.asmVarname}+$scaledIdx+1")
@@ -1322,7 +1530,7 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
             }
             TargetStorageKind.ARRAY -> {
                 if (wordtarget.constArrayIndexValue!=null) {
-                    val scaledIdx = wordtarget.constArrayIndexValue!! * 2
+                    val scaledIdx = wordtarget.constArrayIndexValue!! * 2u
                     asmgen.out("  lda  $sourceName  | sta  ${wordtarget.asmVarname}+$scaledIdx")
                     if(asmgen.isTargetCpu(CpuType.CPU65c02))
                         asmgen.out("  stz  ${wordtarget.asmVarname}+$scaledIdx+1")
@@ -1363,7 +1571,7 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
         // these will be correctly typecasted from a byte to a word value
         if(target.register !in Cx16VirtualRegisters &&
             target.register!=RegisterOrPair.AX && target.register!=RegisterOrPair.AY && target.register!=RegisterOrPair.XY) {
-            if(target.kind==TargetStorageKind.VARIABLE) {
+            if(target.kind== TargetStorageKind.VARIABLE) {
                 val parts = target.asmVarname.split('.')
                 if (parts.size != 2 || parts[0] != "cx16")
                     require(target.datatype in ByteDatatypes)
@@ -1459,7 +1667,7 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
     }
 
     internal fun assignRegisterpairWord(target: AsmAssignTarget, regs: RegisterOrPair) {
-        require(target.datatype in NumericDatatypes)
+        require(target.datatype in NumericDatatypes || target.datatype in PassByReferenceDatatypes)
         if(target.datatype==DataType.FLOAT)
             throw AssemblyError("float value should be from FAC1 not from registerpair memory pointer")
 
@@ -1482,7 +1690,7 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
             }
             TargetStorageKind.ARRAY -> {
                 if (target.constArrayIndexValue!=null) {
-                    val idx = target.constArrayIndexValue!! * 2
+                    val idx = target.constArrayIndexValue!! * 2u
                     when (regs) {
                         RegisterOrPair.AX -> asmgen.out("  sta  ${target.asmVarname}+$idx |  stx  ${target.asmVarname}+$idx+1")
                         RegisterOrPair.AY -> asmgen.out("  sta  ${target.asmVarname}+$idx |  sty  ${target.asmVarname}+$idx+1")
@@ -1586,7 +1794,7 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
             }
             TargetStorageKind.STACK -> {
                 when(regs) {
-                    RegisterOrPair.AY -> asmgen.out("  sta  P8ESTACK_LO,x |  sty  P8ESTACK_HI,x |  dex")
+                    RegisterOrPair.AY -> asmgen.out("  sta  P8ESTACK_LO,x |  tya |  sta  P8ESTACK_HI,x |  dex")
                     RegisterOrPair.AX, RegisterOrPair.XY -> throw AssemblyError("can't use X here")
                     in Cx16VirtualRegisters -> {
                         val srcReg = asmgen.asmSymbolName(regs)
@@ -1612,7 +1820,7 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                     asmgen.out("  stz  ${target.asmVarname} |  stz  ${target.asmVarname}+1")
                 }
                 TargetStorageKind.MEMORY -> {
-                    throw AssemblyError("no asm gen for assign word $word to memory ${target.memory}")
+                    throw AssemblyError("memory is bytes not words")
                 }
                 TargetStorageKind.ARRAY -> {
                     asmgen.loadScaledArrayIndexIntoRegister(target.array!!, DataType.UWORD, CpuRegister.Y)
@@ -1703,15 +1911,15 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
         }
     }
 
-    private fun assignConstantByte(target: AsmAssignTarget, byte: Short) {
-        if(byte==0.toShort() && asmgen.isTargetCpu(CpuType.CPU65c02)) {
+    private fun assignConstantByte(target: AsmAssignTarget, byte: Int) {
+        if(byte==0 && asmgen.isTargetCpu(CpuType.CPU65c02)) {
             // optimize setting zero value for this cpu
             when(target.kind) {
                 TargetStorageKind.VARIABLE -> {
                     asmgen.out("  stz  ${target.asmVarname} ")
                 }
                 TargetStorageKind.MEMORY -> {
-                    asmgen.out("  lda  #${byte.toHex()}")
+                    asmgen.out("  lda  #0")
                     storeRegisterAInMemoryAddress(target.memory!!)
                 }
                 TargetStorageKind.ARRAY -> {
@@ -1875,17 +2083,13 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
             when(target.kind) {
                 TargetStorageKind.VARIABLE -> {
                     asmgen.out("""
-                            lda  $constFloat
-                            sta  ${target.asmVarname}
-                            lda  $constFloat+1
-                            sta  ${target.asmVarname}+1
-                            lda  $constFloat+2
-                            sta  ${target.asmVarname}+2
-                            lda  $constFloat+3
-                            sta  ${target.asmVarname}+3
-                            lda  $constFloat+4
-                            sta  ${target.asmVarname}+4
-                        """)
+                        lda  #<$constFloat
+                        ldy  #>$constFloat
+                        sta  P8ZP_SCRATCH_W1
+                        sty  P8ZP_SCRATCH_W1+1
+                        lda  #<${target.asmVarname}
+                        ldy  #>${target.asmVarname}
+                        jsr  floats.copy_float""")
                 }
                 TargetStorageKind.ARRAY -> {
                     val arrayVarName = target.asmVarname
@@ -1893,17 +2097,13 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                     if (constIndex!=null) {
                         val indexValue = constIndex * program.memsizer.memorySize(DataType.FLOAT)
                         asmgen.out("""
-                            lda  $constFloat
-                            sta  $arrayVarName+$indexValue
-                            lda  $constFloat+1
-                            sta  $arrayVarName+$indexValue+1
-                            lda  $constFloat+2
-                            sta  $arrayVarName+$indexValue+2
-                            lda  $constFloat+3
-                            sta  $arrayVarName+$indexValue+3
-                            lda  $constFloat+4
-                            sta  $arrayVarName+$indexValue+4
-                        """)
+                            lda  #<$constFloat
+                            ldy  #>$constFloat
+                            sta  P8ZP_SCRATCH_W1
+                            sty  P8ZP_SCRATCH_W1+1
+                            lda  #<($arrayVarName+$indexValue)
+                            ldy  #>($arrayVarName+$indexValue)
+                            jsr  floats.copy_float""")
                     } else {
                         val asmvarname = asmgen.asmVariableName(target.array.indexer.indexExpr as IdentifierReference)
                         asmgen.out("""
@@ -1937,7 +2137,7 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
         }
     }
 
-    private fun assignMemoryByte(target: AsmAssignTarget, address: Int?, identifier: IdentifierReference?) {
+    private fun assignMemoryByte(target: AsmAssignTarget, address: UInt?, identifier: IdentifierReference?) {
         if (address != null) {
             when(target.kind) {
                 TargetStorageKind.VARIABLE -> {
@@ -2021,7 +2221,7 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
         }
     }
 
-    private fun assignMemoryByteIntoWord(wordtarget: AsmAssignTarget, address: Int?, identifier: IdentifierReference?) {
+    private fun assignMemoryByteIntoWord(wordtarget: AsmAssignTarget, address: UInt?, identifier: IdentifierReference?) {
         if (address != null) {
             when(wordtarget.kind) {
                 TargetStorageKind.VARIABLE -> {
@@ -2092,52 +2292,14 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
             when(addressExpr) {
                 is NumericLiteralValue, is IdentifierReference -> {
                     assignExpressionToVariable(addressExpr, "P8ZP_SCRATCH_W2", DataType.UWORD, null)
-                    if (asmgen.isTargetCpu(CpuType.CPU65c02))
-                        asmgen.out("  sta  (P8ZP_SCRATCH_W2)")
-                    else
-                        asmgen.out("  ldy  #0 |  sta  (P8ZP_SCRATCH_W2),y")
+                    asmgen.storeAIntoZpPointerVar("P8ZP_SCRATCH_W2")
                 }
                 else -> {
                     // same as above but we need to save the A register
                     asmgen.out("  pha")
                     assignExpressionToVariable(addressExpr, "P8ZP_SCRATCH_W2", DataType.UWORD, null)
                     asmgen.out("  pla")
-                    if (asmgen.isTargetCpu(CpuType.CPU65c02))
-                        asmgen.out("  sta  (P8ZP_SCRATCH_W2)")
-                    else
-                        asmgen.out("  ldy  #0 |  sta  (P8ZP_SCRATCH_W2),y")
-                }
-            }
-        }
-
-        fun storeAIntoPointerVar(pointervar: IdentifierReference) {
-            val sourceName = asmgen.asmVariableName(pointervar)
-            val vardecl = pointervar.targetVarDecl(program)!!
-            val scopedName = vardecl.makeScopedName(vardecl.name)
-            if (asmgen.isTargetCpu(CpuType.CPU65c02)) {
-                if (asmgen.isZpVar(scopedName)) {
-                    // pointervar is already in the zero page, no need to copy
-                    asmgen.out("  sta  ($sourceName)")
-                } else {
-                    asmgen.out("""
-                    ldy  $sourceName
-                    sty  P8ZP_SCRATCH_W2
-                    ldy  $sourceName+1
-                    sty  P8ZP_SCRATCH_W2+1
-                    sta  (P8ZP_SCRATCH_W2)""")
-                }
-            } else {
-                if (asmgen.isZpVar(scopedName)) {
-                    // pointervar is already in the zero page, no need to copy
-                    asmgen.out(" ldy  #0 |  sta  ($sourceName),y")
-                } else {
-                    asmgen.out("""
-                    ldy  $sourceName
-                    sty  P8ZP_SCRATCH_W2
-                    ldy  $sourceName+1
-                    sty  P8ZP_SCRATCH_W2+1
-                    ldy  #0
-                    sta  (P8ZP_SCRATCH_W2),y""")
+                    asmgen.storeAIntoZpPointerVar("P8ZP_SCRATCH_W2")
                 }
             }
         }
@@ -2147,7 +2309,7 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                 asmgen.out("  sta  ${addressLv.number.toHex()}")
             }
             addressExpr is IdentifierReference -> {
-                storeAIntoPointerVar(addressExpr)
+                asmgen.storeAIntoPointerVar(addressExpr)
             }
             addressExpr is BinaryExpression -> {
                 if(!asmgen.tryOptimizedPointerAccessWithA(addressExpr, true))
@@ -2157,9 +2319,9 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
         }
     }
 
-    internal fun assignExpressionToRegister(expr: Expression, register: RegisterOrPair) {
+    internal fun assignExpressionToRegister(expr: Expression, register: RegisterOrPair, signed: Boolean) {
         val src = AsmAssignSource.fromAstSource(expr, program, asmgen)
-        val tgt = AsmAssignTarget.fromRegisters(register, null, program, asmgen)
+        val tgt = AsmAssignTarget.fromRegisters(register, signed, null, program, asmgen)
         val assign = AsmAssignment(src, tgt, false, program.memsizer, expr.position)
         translateNormalAssignment(assign)
     }
@@ -2171,8 +2333,8 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
         translateNormalAssignment(assign)
     }
 
-    internal fun assignVariableToRegister(asmVarName: String, register: RegisterOrPair) {
-        val tgt = AsmAssignTarget.fromRegisters(register, null, program, asmgen)
+    internal fun assignVariableToRegister(asmVarName: String, register: RegisterOrPair, signed: Boolean) {
+        val tgt = AsmAssignTarget.fromRegisters(register, signed, null, program, asmgen)
         val src = AsmAssignSource(SourceStorageKind.VARIABLE, program, asmgen, tgt.datatype, variableAsmName = asmVarName)
         val assign = AsmAssignment(src, tgt, false, program.memsizer, Position.DUMMY)
         translateNormalAssignment(assign)

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

@@ -1,18 +1,17 @@
-package prog8.compiler.target.cpu6502.codegen.assignment
+package prog8.codegen.target.cpu6502.codegen.assignment
 
 import prog8.ast.Program
 import prog8.ast.base.*
 import prog8.ast.expressions.*
 import prog8.ast.statements.Subroutine
 import prog8.ast.toHex
-import prog8.compiler.AssemblyError
-import prog8.compiler.target.CpuType
-import prog8.compiler.target.cpu6502.codegen.AsmGen
-import prog8.compiler.target.cpu6502.codegen.ExpressionsAsmGen
+import prog8.codegen.target.AssemblyError
+import prog8.codegen.target.cpu6502.codegen.AsmGen
+import prog8.compilerinterface.CpuType
+
 
 internal class AugmentableAssignmentAsmGen(private val program: Program,
                                            private val assignmentAsmGen: AssignmentAsmGen,
-                                           private val exprAsmGen: ExpressionsAsmGen,
                                            private val asmgen: AsmGen
 ) {
     fun translate(assign: AsmAssignment) {
@@ -22,15 +21,14 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
         when (val value = assign.source.expression!!) {
             is PrefixExpression -> {
                 // A = -A , A = +A, A = ~A, A = not A
+                val target = assignmentAsmGen.virtualRegsToVariables(assign.target)
                 val itype = value.inferType(program)
-                if(!itype.isKnown)
-                    throw AssemblyError("unknown dt")
-                val type = itype.getOr(DataType.UNDEFINED)
+                val type = itype.getOrElse { throw AssemblyError("unknown dt") }
                 when (value.operator) {
                     "+" -> {}
-                    "-" -> inplaceNegate(assign.target, type)
-                    "~" -> inplaceInvert(assign.target, type)
-                    "not" -> inplaceBooleanNot(assign.target, type)
+                    "-" -> inplaceNegate(target, type)
+                    "~" -> inplaceInvert(target, type)
+                    "not" -> inplaceBooleanNot(target, type)
                     else -> throw AssemblyError("invalid prefix operator")
                 }
             }
@@ -47,7 +45,7 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
             return inplaceModification(target, binExpr.operator, binExpr.right)
         }
 
-        if (binExpr.operator in associativeOperators) {
+        if (binExpr.operator in AssociativeOperators) {
             if (binExpr.right isSameAs astTarget) {
                 // A = 5 <operator> A
                 return inplaceModification(target, binExpr.operator, binExpr.left)
@@ -102,10 +100,66 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
             }
         }
 
-        throw FatalAstException("assignment should be augmentable $binExpr")
+        val leftBinExpr = binExpr.left as? BinaryExpression
+        val rightBinExpr = binExpr.right as? BinaryExpression
+        if(leftBinExpr!=null && rightBinExpr==null) {
+            if(leftBinExpr.left isSameAs astTarget) {
+                // X = (X <oper> Right) <oper> Something
+                inplaceModification(target, leftBinExpr.operator, leftBinExpr.right)
+                inplaceModification(target, binExpr.operator, binExpr.right)
+                return
+            }
+            if(leftBinExpr.right isSameAs astTarget) {
+                // X = (Left <oper> X) <oper> Something
+                if(leftBinExpr.operator in AssociativeOperators) {
+                    inplaceModification(target, leftBinExpr.operator, leftBinExpr.left)
+                    inplaceModification(target, binExpr.operator, binExpr.right)
+                    return
+                } else {
+                    throw AssemblyError("operands in wrong order for non-associative operator")
+                }
+            }
+        }
+        if(leftBinExpr==null && rightBinExpr!=null) {
+            if(rightBinExpr.left isSameAs astTarget) {
+                // X = Something <oper> (X <oper> Right)
+                if(binExpr.operator in AssociativeOperators) {
+                    inplaceModification(target, rightBinExpr.operator, rightBinExpr.right)
+                    inplaceModification(target, binExpr.operator, binExpr.left)
+                    return
+                } else {
+                    throw AssemblyError("operands in wrong order for non-associative operator")
+                }
+            }
+            if(rightBinExpr.right isSameAs astTarget) {
+                // X = Something <oper> (Left <oper> X)
+                if(binExpr.operator in AssociativeOperators && rightBinExpr.operator in AssociativeOperators) {
+                    inplaceModification(target, rightBinExpr.operator, rightBinExpr.left)
+                    inplaceModification(target, binExpr.operator, binExpr.left)
+                    return
+                } else {
+                    throw AssemblyError("operands in wrong order for non-associative operator")
+                }
+            }
+        }
+
+        throw FatalAstException("assignment should follow augmentable rules $binExpr")
     }
 
-    private fun inplaceModification(target: AsmAssignTarget, operator: String, value: Expression) {
+    private fun inplaceModification(target: AsmAssignTarget, operator: String, origValue: Expression) {
+
+        // the asm-gen code can deal with situations where you want to assign a byte into a word.
+        // it will create the most optimized code to do this (so it type-extends for us).
+        // But we can't deal with writing a word into a byte - explicit typeconversion is required
+        val value = if(program.memsizer.memorySize(origValue.inferType(program).getOrElse { throw AssemblyError("unknown dt") }) > program.memsizer.memorySize(target.datatype)) {
+            val typecast = TypecastExpression(origValue, target.datatype, true, origValue.position)
+            typecast.linkParents(origValue.parent)
+            typecast
+        }
+        else {
+            origValue
+        }
+
         val valueLv = (value as? NumericLiteralValue)?.number
         val ident = value as? IdentifierReference
         val memread = value as? DirectMemoryRead
@@ -181,7 +235,8 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                         }
                     }
                     else -> {
-                        asmgen.translateExpression(memory.addressExpression)
+                        // TODO use some other evaluation here; don't use the estack to transfer the address to read/write from
+                        asmgen.assignExpressionTo(memory.addressExpression, AsmAssignTarget(TargetStorageKind.STACK, program, asmgen, DataType.UWORD, memory.definingSubroutine))
                         asmgen.out("  jsr  prog8_lib.read_byte_from_address_on_stack |  sta  P8ZP_SCRATCH_B1")
                         when {
                             valueLv != null -> inplaceModification_byte_litval_to_variable("P8ZP_SCRATCH_B1", DataType.UBYTE, operator, valueLv.toInt())
@@ -246,19 +301,37 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                         indexVar!=null -> {
                             when (target.datatype) {
                                 in ByteDatatypes -> {
-                                    val tgt = AsmAssignTarget.fromRegisters(RegisterOrPair.A, null, program, asmgen)
+                                    val tgt =
+                                        AsmAssignTarget.fromRegisters(
+                                            RegisterOrPair.A,
+                                            target.datatype == DataType.BYTE, null,
+                                            program,
+                                            asmgen
+                                        )
                                     val assign = AsmAssignment(target.origAssign.source, tgt, false, program.memsizer, value.position)
                                     assignmentAsmGen.translateNormalAssignment(assign)
                                     assignmentAsmGen.assignRegisterByte(target, CpuRegister.A)
                                 }
                                 in WordDatatypes -> {
-                                    val tgt = AsmAssignTarget.fromRegisters(RegisterOrPair.AY, null, program, asmgen)
+                                    val tgt =
+                                        AsmAssignTarget.fromRegisters(
+                                            RegisterOrPair.AY,
+                                            target.datatype == DataType.WORD, null,
+                                            program,
+                                            asmgen
+                                        )
                                     val assign = AsmAssignment(target.origAssign.source, tgt, false, program.memsizer, value.position)
                                     assignmentAsmGen.translateNormalAssignment(assign)
                                     assignmentAsmGen.assignRegisterpairWord(target, RegisterOrPair.AY)
                                 }
                                 DataType.FLOAT -> {
-                                    val tgt = AsmAssignTarget.fromRegisters(RegisterOrPair.FAC1, null, program, asmgen)
+                                    val tgt =
+                                        AsmAssignTarget.fromRegisters(
+                                            RegisterOrPair.FAC1,
+                                            true, null,
+                                            program,
+                                            asmgen
+                                        )
                                     val assign = AsmAssignment(target.origAssign.source, tgt, false, program.memsizer, value.position)
                                     assignmentAsmGen.translateNormalAssignment(assign)
                                     assignmentAsmGen.assignFAC1float(target)
@@ -270,17 +343,15 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                     }
                 }
             }
-            TargetStorageKind.REGISTER -> throw AssemblyError("missing codegen for reg in-place modification")
-            TargetStorageKind.STACK -> throw AssemblyError("missing codegen for stack in-place modification")
+            TargetStorageKind.REGISTER -> throw AssemblyError("no asm gen for reg in-place modification")
+            TargetStorageKind.STACK -> throw AssemblyError("no asm gen for stack in-place modification")
         }
     }
 
     private fun tryRemoveRedundantCast(value: TypecastExpression, target: AsmAssignTarget, operator: String): Boolean {
         if (target.datatype == value.type) {
             val childIDt = value.expression.inferType(program)
-            if(!childIDt.isKnown)
-                throw AssemblyError("unknown dt")
-            val childDt = childIDt.getOr(DataType.UNDEFINED)
+            val childDt = childIDt.getOrElse { throw AssemblyError("unknown dt") }
             if (value.type!=DataType.FLOAT && (value.type.equalsSize(childDt) || value.type.largerThan(childDt))) {
                 // this typecast is redundant here; the rest of the code knows how to deal with the uncasted value.
                 // (works for integer types, not for float.)
@@ -293,13 +364,14 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
 
     private fun inplaceModification_byte_value_to_pointer(pointervar: IdentifierReference, operator: String, value: Expression) {
         asmgen.assignExpressionToVariable(value, "P8ZP_SCRATCH_B1", DataType.UBYTE, null)
+        val sourceName = asmgen.loadByteFromPointerIntoA(pointervar)
         when (operator) {
             // note: ** (power) operator requires floats.
             "+" -> asmgen.out("  clc |  adc  P8ZP_SCRATCH_B1")
             "-" -> asmgen.out("  sec |  sbc  P8ZP_SCRATCH_B1")
-            "*" -> asmgen.out("  ldy  P8ZP_SCRATCH_B1 |  jsr  math.multiply_bytes |  ldy  #0")
-            "/" -> asmgen.out("  ldy  P8ZP_SCRATCH_B1 |  jsr  math.divmod_ub_asm |  tya |  ldy  #0")
-            "%" -> asmgen.out("  ldy  P8ZP_SCRATCH_B1 |  jsr  math.divmod_ub_asm |  ldy  #0")
+            "*" -> asmgen.out("  ldy  P8ZP_SCRATCH_B1 |  jsr  math.multiply_bytes")
+            "/" -> asmgen.out("  ldy  P8ZP_SCRATCH_B1 |  jsr  math.divmod_ub_asm |  tya")
+            "%" -> asmgen.out("  ldy  P8ZP_SCRATCH_B1 |  jsr  math.divmod_ub_asm")
             "<<" -> {
                 asmgen.out("""
                     ldy  P8ZP_SCRATCH_B1
@@ -323,8 +395,7 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
             "^", "xor" -> asmgen.out(" eor  P8ZP_SCRATCH_B1")
             else -> throw AssemblyError("invalid operator for in-place modification $operator")
         }
-        val sourceName = asmgen.loadByteFromPointerIntoA(pointervar)
-        asmgen.out("  sta  ($sourceName),y")
+        asmgen.storeAIntoZpPointerVar(sourceName)
     }
 
     private fun inplaceModification_byte_variable_to_pointer(pointervar: IdentifierReference, operator: String, value: IdentifierReference) {
@@ -335,9 +406,9 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
             // note: ** (power) operator requires floats.
             "+" -> asmgen.out("  clc |  adc  $otherName")
             "-" -> asmgen.out("  sec |  sbc  $otherName")
-            "*" -> asmgen.out("  ldy  $otherName |  jsr  math.multiply_bytes |  ldy  #0")
-            "/" -> asmgen.out("  ldy  $otherName |  jsr  math.divmod_ub_asm |  tya |  ldy  #0")
-            "%" -> asmgen.out("  ldy  $otherName |  jsr  math.divmod_ub_asm |  ldy  #0")
+            "*" -> asmgen.out("  ldy  $otherName |  jsr  math.multiply_bytes")
+            "/" -> asmgen.out("  ldy  $otherName |  jsr  math.divmod_ub_asm |  tya")
+            "%" -> asmgen.out("  ldy  $otherName |  jsr  math.divmod_ub_asm")
             "<<" -> {
                 asmgen.out("""
                         ldy  $otherName
@@ -361,7 +432,7 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
             "^", "xor" -> asmgen.out(" eor  $otherName")
             else -> throw AssemblyError("invalid operator for in-place modification $operator")
         }
-        asmgen.out("  sta  ($sourceName),y")
+        asmgen.storeAIntoZpPointerVar(sourceName)
     }
 
     private fun inplaceModification_byte_litval_to_pointer(pointervar: IdentifierReference, operator: String, value: Int) {
@@ -370,63 +441,63 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
             "+" -> {
                 val sourceName = asmgen.loadByteFromPointerIntoA(pointervar)
                 asmgen.out("  clc |  adc  #$value")
-                asmgen.out("  sta  ($sourceName),y")
+                asmgen.storeAIntoZpPointerVar(sourceName)
             }
             "-" -> {
                 val sourceName = asmgen.loadByteFromPointerIntoA(pointervar)
                 asmgen.out("  sec |  sbc  #$value")
-                asmgen.out("  sta  ($sourceName),y")
+                asmgen.storeAIntoZpPointerVar(sourceName)
             }
             "*" -> {
                 val sourceName = asmgen.loadByteFromPointerIntoA(pointervar)
                 if(value in asmgen.optimizedByteMultiplications)
                     asmgen.out("  jsr  math.mul_byte_${value}")
                 else
-                    asmgen.out("  ldy  #$value |  jsr  math.multiply_bytes |  ldy  #0")
-                asmgen.out("  sta  ($sourceName),y")
+                    asmgen.out("  ldy  #$value |  jsr  math.multiply_bytes")
+                asmgen.storeAIntoZpPointerVar(sourceName)
             }
             "/" -> {
                 val sourceName = asmgen.loadByteFromPointerIntoA(pointervar)
                 if(value==0)
                     throw AssemblyError("division by zero")
-                asmgen.out("  ldy  #$value |  jsr  math.divmod_ub_asm |  tya |  ldy  #0")
-                asmgen.out("  sta  ($sourceName),y")
+                asmgen.out("  ldy  #$value |  jsr  math.divmod_ub_asm |  tya")
+                asmgen.storeAIntoZpPointerVar(sourceName)
             }
             "%" -> {
                 val sourceName = asmgen.loadByteFromPointerIntoA(pointervar)
                 if(value==0)
                     throw AssemblyError("division by zero")
-                asmgen.out("  ldy  #$value |  jsr  math.divmod_ub_asm |  ldy  #0")
-                asmgen.out("  sta  ($sourceName),y")
+                asmgen.out("  ldy  #$value |  jsr  math.divmod_ub_asm")
+                asmgen.storeAIntoZpPointerVar(sourceName)
             }
             "<<" -> {
                 if (value > 0) {
                     val sourceName = asmgen.loadByteFromPointerIntoA(pointervar)
-                    repeat(value) { asmgen.out(" asl  a") }
-                    asmgen.out("  sta  ($sourceName),y")
+                    repeat(value) { asmgen.out("  asl  a") }
+                    asmgen.storeAIntoZpPointerVar(sourceName)
                 }
             }
             ">>" -> {
                 if (value > 0) {
                     val sourceName = asmgen.loadByteFromPointerIntoA(pointervar)
-                    repeat(value) { asmgen.out(" lsr  a") }
-                    asmgen.out("  sta  ($sourceName),y")
+                    repeat(value) { asmgen.out("  lsr  a") }
+                    asmgen.storeAIntoZpPointerVar(sourceName)
                 }
             }
             "&", "and" -> {
                 val sourceName = asmgen.loadByteFromPointerIntoA(pointervar)
                 asmgen.out("  and  #$value")
-                asmgen.out("  sta  ($sourceName),y")
+                asmgen.storeAIntoZpPointerVar(sourceName)
             }
             "|", "or" -> {
                 val sourceName = asmgen.loadByteFromPointerIntoA(pointervar)
                 asmgen.out("  ora  #$value")
-                asmgen.out("  sta  ($sourceName),y")
+                asmgen.storeAIntoZpPointerVar(sourceName)
             }
             "^", "xor" -> {
                 val sourceName = asmgen.loadByteFromPointerIntoA(pointervar)
                 asmgen.out("  eor  #$value")
-                asmgen.out("  sta  ($sourceName),y")
+                asmgen.storeAIntoZpPointerVar(sourceName)
             }
             else -> throw AssemblyError("invalid operator for in-place modification $operator")
         }
@@ -503,6 +574,26 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                 asmgen.assignExpressionToRegister(value, RegisterOrPair.A)
                 asmgen.out("  eor  $name |  sta  $name")
             }
+            "==" -> {
+                asmgen.assignExpressionToRegister(value, RegisterOrPair.A)
+                asmgen.out("""
+                    cmp  $name
+                    beq  +
+                    lda  #0
+                    beq  ++
++                   lda  #1
++                   sta  $name""")
+            }
+            "!=" -> {
+                asmgen.assignExpressionToRegister(value, RegisterOrPair.A)
+                asmgen.out("""
+                    cmp  $name
+                    beq  +
+                    lda  #1
+                    bne  ++
++                   lda  #0
++                   sta  $name""")
+            }
             else -> throw AssemblyError("invalid operator for in-place modification $operator")
         }
     }
@@ -560,6 +651,26 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
             "&", "and" -> asmgen.out(" lda  $name |  and  $otherName |  sta  $name")
             "|", "or" -> asmgen.out(" lda  $name |  ora  $otherName |  sta  $name")
             "^", "xor" -> asmgen.out(" lda  $name |  eor  $otherName |  sta  $name")
+            "==" -> {
+                asmgen.out("""
+                    lda  $otherName
+                    cmp  $name
+                    beq  +
+                    lda  #0
+                    bne  ++
++                   lda  #1
++                   sta  $name""")
+            }
+            "!=" -> {
+                asmgen.out("""
+                    lda  $otherName
+                    cmp  $name
+                    beq  +
+                    lda  #1
+                    bne  ++
++                   lda  #0
++                   sta  $name""")
+            }
             else -> throw AssemblyError("invalid operator for in-place modification $operator")
         }
     }
@@ -631,6 +742,26 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
             "&", "and" -> asmgen.out(" lda  $name |  and  #$value |  sta  $name")
             "|", "or" -> asmgen.out(" lda  $name |  ora  #$value |  sta  $name")
             "^", "xor" -> asmgen.out(" lda  $name |  eor  #$value |  sta  $name")
+            "==" -> {
+                asmgen.out("""
+                    lda  $name
+                    cmp  #$value
+                    beq  +
+                    lda  #0
+                    beq  ++
++                   lda  #1
++                   sta  $name""")
+            }
+            "!=" -> {
+                asmgen.out("""
+                    lda  $name
+                    cmp  #$value
+                    beq  +
+                    lda  #1
+                    bne  ++
++                   lda  #0
++                   sta  $name""")
+            }
             else -> throw AssemblyError("invalid operator for in-place modification $operator")
         }
     }
@@ -638,14 +769,14 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
     private fun inplaceModification_byte_memread_to_variable(name: String, dt: DataType, operator: String, memread: DirectMemoryRead) {
         when (operator) {
             "+" -> {
-                exprAsmGen.translateDirectMemReadExpression(memread, false)
+                asmgen.translateDirectMemReadExpressionToRegAorStack(memread, false)
                 asmgen.out("""
                     clc
                     adc  $name
                     sta  $name""")
             }
             "-" -> {
-                exprAsmGen.translateDirectMemReadExpression(memread, false)
+                asmgen.translateDirectMemReadExpressionToRegAorStack(memread, false)
                 asmgen.out("""
                     sta  P8ZP_SCRATCH_B1
                     lda  $name
@@ -654,15 +785,15 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                     sta  $name""")
             }
             "|", "or" -> {
-                exprAsmGen.translateDirectMemReadExpression(memread, false)
+                asmgen.translateDirectMemReadExpressionToRegAorStack(memread, false)
                 asmgen.out("  ora  $name  |  sta  $name")
             }
             "&", "and" -> {
-                exprAsmGen.translateDirectMemReadExpression(memread, false)
+                asmgen.translateDirectMemReadExpressionToRegAorStack(memread, false)
                 asmgen.out("  and  $name  |  sta  $name")
             }
             "^", "xor" -> {
-                exprAsmGen.translateDirectMemReadExpression(memread, false)
+                asmgen.translateDirectMemReadExpressionToRegAorStack(memread, false)
                 asmgen.out("  eor  $name  |  sta  $name")
             }
             // TODO: tuned code for more operators
@@ -675,7 +806,7 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
     private fun inplaceModification_word_memread_to_variable(name: String, dt: DataType, operator: String, memread: DirectMemoryRead) {
         when (operator) {
             "+" -> {
-                exprAsmGen.translateDirectMemReadExpression(memread, false)
+                asmgen.translateDirectMemReadExpressionToRegAorStack(memread, false)
                 asmgen.out("""
                     clc
                     adc  $name
@@ -685,7 +816,7 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
 +""")
             }
             "-" -> {
-                exprAsmGen.translateDirectMemReadExpression(memread, false)
+                asmgen.translateDirectMemReadExpressionToRegAorStack(memread, false)
                 asmgen.out("""
                     sta  P8ZP_SCRATCH_B1
                     lda  $name
@@ -697,11 +828,11 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
 +""")
             }
             "|", "or" -> {
-                exprAsmGen.translateDirectMemReadExpression(memread, false)
+                asmgen.translateDirectMemReadExpressionToRegAorStack(memread, false)
                 asmgen.out("  ora  $name  |  sta  $name")
             }
             "&", "and" -> {
-                exprAsmGen.translateDirectMemReadExpression(memread, false)
+                asmgen.translateDirectMemReadExpressionToRegAorStack(memread, false)
                 asmgen.out("  and  $name  |  sta  $name")
                 if(dt in WordDatatypes) {
                     if(asmgen.isTargetCpu(CpuType.CPU65c02))
@@ -711,7 +842,7 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                 }
             }
             "^", "xor" -> {
-                exprAsmGen.translateDirectMemReadExpression(memread, false)
+                asmgen.translateDirectMemReadExpressionToRegAorStack(memread, false)
                 asmgen.out("  eor  $name  |  sta  $name")
             }
             // TODO: tuned code for more operators
@@ -1084,7 +1215,8 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                             sta  $name
                             lda  P8ZP_SCRATCH_W2+1
                             sta  $name+1
-                        """)                    }
+                        """)
+                    }
                     "<<" -> {
                         asmgen.out("""
                         ldy  $otherName
@@ -1216,9 +1348,7 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
         // because the value is evaluated onto the eval stack (=slow).
 
         val valueiDt = value.inferType(program)
-        if(!valueiDt.isKnown)
-            throw AssemblyError("unknown dt")
-        val valueDt = valueiDt.getOr(DataType.UNDEFINED)
+        val valueDt = valueiDt.getOrElse { throw AssemblyError("unknown dt") }
 
         fun multiplyVarByWordInAY() {
             asmgen.out("""
@@ -1705,7 +1835,7 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
         }
     }
 
-    private fun inplaceBooleanNot(target: AsmAssignTarget, dt: DataType) {
+    internal fun inplaceBooleanNot(target: AsmAssignTarget, dt: DataType) {
         when (dt) {
             DataType.UBYTE -> {
                 when (target.kind) {
@@ -1735,23 +1865,43 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                                     beq  +
                                     lda  #1
 +                                   eor  #1""")
-                                asmgen.out("  sta  ($sourceName),y")
+                                asmgen.storeAIntoZpPointerVar(sourceName)
                             }
                             else -> {
                                 asmgen.assignExpressionToVariable(mem.addressExpression, "P8ZP_SCRATCH_W2", DataType.UWORD, target.scope)
+                                asmgen.loadAFromZpPointerVar("P8ZP_SCRATCH_W2")
                                 asmgen.out("""
-                                    ldy  #0
-                                    lda  (P8ZP_SCRATCH_W2),y
                                     beq  +
                                     lda  #1
-+                                   eor  #1                                    
-                                    sta  (P8ZP_SCRATCH_W2),y""")
++                                   eor  #1""")
+                                asmgen.storeAIntoZpPointerVar("P8ZP_SCRATCH_W2")
                             }
                         }
                     }
-                    TargetStorageKind.ARRAY -> throw AssemblyError("missing codegen for in-place not of ubyte array")
-                    TargetStorageKind.REGISTER -> throw AssemblyError("missing codegen for reg not")
-                    TargetStorageKind.STACK -> throw AssemblyError("missing codegen for stack not")
+                    TargetStorageKind.REGISTER -> {
+                        when(target.register!!) {
+                            RegisterOrPair.A -> asmgen.out("""
+                                cmp  #0
+                                beq  +
+                                lda  #1
++                               eor  #1""")
+                            RegisterOrPair.X -> asmgen.out("""
+                                txa
+                                beq  +
+                                lda  #1
++                               eor  #1
+                                tax""")
+                            RegisterOrPair.Y -> asmgen.out("""
+                                tya
+                                beq  +
+                                lda  #1
++                               eor  #1
+                                tay""")
+                            else -> throw AssemblyError("invalid reg dt for byte not")
+                        }
+                    }
+                    TargetStorageKind.STACK -> TODO("no asm gen for byte stack not")
+                    else -> throw AssemblyError("no asm gen for in-place not of ubyte ${target.kind}")
                 }
             }
             DataType.UWORD -> {
@@ -1767,17 +1917,55 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                             lsr  a
                             sta  ${target.asmVarname}+1""")
                     }
-                    TargetStorageKind.MEMORY -> throw AssemblyError("no asm gen for uword-memory not")
-                    TargetStorageKind.ARRAY -> throw AssemblyError("missing codegen for in-place not of uword array")
-                    TargetStorageKind.REGISTER -> throw AssemblyError("missing codegen for reg not")
-                    TargetStorageKind.STACK -> throw AssemblyError("missing codegen for stack not")
+                    TargetStorageKind.REGISTER -> {
+                        when(target.register!!) {
+                            RegisterOrPair.AX -> {
+                                asmgen.out("""
+                                    stx  P8ZP_SCRATCH_REG
+                                    ora  P8ZP_SCRATCH_REG
+                                    beq  +
+                                    lda  #0
+                                    tax
+                                    beq  ++
+        +                           lda  #1
+        +""")
+                            }
+                            RegisterOrPair.AY -> {
+                                asmgen.out("""
+                                    sty  P8ZP_SCRATCH_REG
+                                    ora  P8ZP_SCRATCH_REG
+                                    beq  +
+                                    lda  #0
+                                    tay
+                                    beq  ++
+        +                           lda  #1
+        +""")
+                            }
+                            RegisterOrPair.XY -> {
+                                asmgen.out("""
+                                    stx  P8ZP_SCRATCH_REG
+                                    tya
+                                    ora  P8ZP_SCRATCH_REG
+                                    beq  +
+                                    ldy  #0
+                                    ldx  #0
+                                    beq  ++
+        +                           ldx  #1
+        +""")
+                            }
+                            in Cx16VirtualRegisters -> throw AssemblyError("cx16 virtual regs should be variables, not real registers")
+                            else -> throw AssemblyError("invalid reg dt for word not")
+                        }
+                    }
+                    TargetStorageKind.STACK -> TODO("no asm gen for word stack not")
+                    else -> throw AssemblyError("no asm gen for in-place not of uword for ${target.kind}")
                 }
             }
             else -> throw AssemblyError("boolean-not of invalid type")
         }
     }
 
-    private fun inplaceInvert(target: AsmAssignTarget, dt: DataType) {
+    internal fun inplaceInvert(target: AsmAssignTarget, dt: DataType) {
         when (dt) {
             DataType.UBYTE -> {
                 when (target.kind) {
@@ -1807,14 +1995,21 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                                 asmgen.out("""
                                     ldy  #0
                                     lda  (P8ZP_SCRATCH_W2),y
-                                    eor  #255
-                                    sta  (P8ZP_SCRATCH_W2),y""")
+                                    eor  #255""")
+                                asmgen.storeAIntoZpPointerVar("P8ZP_SCRATCH_W2")
                             }
                         }
                     }
-                    TargetStorageKind.ARRAY -> throw AssemblyError("missing codegen for in-place invert ubyte array")
-                    TargetStorageKind.REGISTER -> throw AssemblyError("missing codegen for reg invert")
-                    TargetStorageKind.STACK -> throw AssemblyError("missing codegen for stack invert")
+                    TargetStorageKind.REGISTER -> {
+                        when(target.register!!) {
+                            RegisterOrPair.A -> asmgen.out("  eor  #255")
+                            RegisterOrPair.X -> asmgen.out("  txa |  eor  #255 |  tax")
+                            RegisterOrPair.Y -> asmgen.out("  tya |  eor  #255 |  tay")
+                            else -> throw AssemblyError("invalid reg dt for byte invert")
+                        }
+                    }
+                    TargetStorageKind.STACK -> TODO("no asm gen for byte stack invert")
+                    else -> throw AssemblyError("no asm gen for in-place invert ubyte for ${target.kind}")
                 }
             }
             DataType.UWORD -> {
@@ -1828,17 +2023,24 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                             eor  #255
                             sta  ${target.asmVarname}+1""")
                     }
-                    TargetStorageKind.MEMORY -> throw AssemblyError("no asm gen for uword-memory invert")
-                    TargetStorageKind.ARRAY -> throw AssemblyError("missing codegen for in-place invert uword array")
-                    TargetStorageKind.REGISTER -> throw AssemblyError("missing codegen for reg invert")
-                    TargetStorageKind.STACK -> throw AssemblyError("missing codegen for stack invert")
+                    TargetStorageKind.REGISTER -> {
+                        when(target.register!!) {
+                            RegisterOrPair.AX -> asmgen.out("  pha |  txa |  eor  #255 |  tax |  pla |  eor  #255")
+                            RegisterOrPair.AY -> asmgen.out("  pha |  tya |  eor  #255 |  tay |  pla |  eor  #255")
+                            RegisterOrPair.XY -> asmgen.out("  txa |  eor  #255 |  tax |  tya |  eor  #255 |  tay")
+                            in Cx16VirtualRegisters -> throw AssemblyError("cx16 virtual regs should be variables, not real registers")
+                            else -> throw AssemblyError("invalid reg dt for word invert")
+                        }
+                    }
+                    TargetStorageKind.STACK -> TODO("no asm gen for word stack invert")
+                    else -> throw AssemblyError("no asm gen for in-place invert uword for ${target.kind}")
                 }
             }
             else -> throw AssemblyError("invert of invalid type")
         }
     }
 
-    private fun inplaceNegate(target: AsmAssignTarget, dt: DataType) {
+    internal fun inplaceNegate(target: AsmAssignTarget, dt: DataType) {
         when (dt) {
             DataType.BYTE -> {
                 when (target.kind) {
@@ -1849,10 +2051,23 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                             sbc  ${target.asmVarname}
                             sta  ${target.asmVarname}""")
                     }
-                    TargetStorageKind.MEMORY -> throw AssemblyError("can't in-place negate memory ubyte")
-                    TargetStorageKind.ARRAY -> throw AssemblyError("missing codegen for in-place negate byte array")
-                    TargetStorageKind.REGISTER -> throw AssemblyError("missing codegen for reg negate")
-                    TargetStorageKind.STACK -> throw AssemblyError("missing codegen for stack negate")
+                    TargetStorageKind.REGISTER -> {
+                        when(target.register!!) {
+                            RegisterOrPair.A -> {
+                                if(asmgen.isTargetCpu(CpuType.CPU65c02))
+                                    asmgen.out("  eor  #255 |  ina")
+                                else
+                                    asmgen.out("  eor  #255 |  clc |  adc  #1")
+
+                            }
+                            RegisterOrPair.X -> asmgen.out("  txa |  eor  #255 |  tax |  inx")
+                            RegisterOrPair.Y -> asmgen.out("  tya |  eor  #255 |  tay |  iny")
+                            else -> throw AssemblyError("invalid reg dt for byte negate")
+                        }
+                    }
+                    TargetStorageKind.MEMORY -> throw AssemblyError("memory is ubyte, can't in-place negate")
+                    TargetStorageKind.STACK -> TODO("no asm gen for byte stack negate")
+                    else -> throw AssemblyError("no asm gen for in-place negate byte")
                 }
             }
             DataType.WORD -> {
@@ -1867,10 +2082,52 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                             sbc  ${target.asmVarname}+1
                             sta  ${target.asmVarname}+1""")
                     }
-                    TargetStorageKind.ARRAY -> throw AssemblyError("missing codegen for in-place negate word array")
-                    TargetStorageKind.MEMORY -> throw AssemblyError("no asm gen for word memory negate")
-                    TargetStorageKind.REGISTER -> throw AssemblyError("missing codegen for reg negate")
-                    TargetStorageKind.STACK -> throw AssemblyError("missing codegen for stack negate")
+                    TargetStorageKind.REGISTER -> {
+                        when(target.register!!) { //P8ZP_SCRATCH_REG
+                            RegisterOrPair.AX -> {
+                                asmgen.out("""
+                                    sta  P8ZP_SCRATCH_REG
+                                    stx  P8ZP_SCRATCH_REG+1
+                                    lda  #0
+                                    sec
+                                    sbc  P8ZP_SCRATCH_REG
+                                    pha
+                                    lda  #0
+                                    sbc  P8ZP_SCRATCH_REG+1
+                                    tax
+                                    pla""")
+                            }
+                            RegisterOrPair.AY -> {
+                                asmgen.out("""
+                                    sta  P8ZP_SCRATCH_REG
+                                    sty  P8ZP_SCRATCH_REG+1
+                                    lda  #0
+                                    sec
+                                    sbc  P8ZP_SCRATCH_REG
+                                    pha
+                                    lda  #0
+                                    sbc  P8ZP_SCRATCH_REG+1
+                                    tay
+                                    pla""")
+                            }
+                            RegisterOrPair.XY -> {
+                                asmgen.out("""
+                                    stx  P8ZP_SCRATCH_REG
+                                    sty  P8ZP_SCRATCH_REG+1
+                                    lda  #0
+                                    sec
+                                    sbc  P8ZP_SCRATCH_REG
+                                    tax
+                                    lda  #0
+                                    sbc  P8ZP_SCRATCH_REG+1
+                                    tay""")
+                            }
+                            in Cx16VirtualRegisters -> throw AssemblyError("cx16 virtual regs should be variables, not real registers")
+                            else -> throw AssemblyError("invalid reg dt for word neg")
+                        }
+                    }
+                    TargetStorageKind.STACK -> TODO("no asm gen for word stack negate")
+                    else -> throw AssemblyError("no asm gen for in-place negate word")
                 }
             }
             DataType.FLOAT -> {
@@ -1883,12 +2140,11 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                             sta  ${target.asmVarname}+1
                         """)
                     }
-                    TargetStorageKind.ARRAY -> throw AssemblyError("missing codegen for in-place negate float array")
-                    TargetStorageKind.STACK -> throw AssemblyError("missing codegen for stack float negate")
-                    else -> throw AssemblyError("weird target kind for float")
+                    TargetStorageKind.STACK -> TODO("no asm gen for float stack negate")
+                    else -> throw AssemblyError("weird target kind for inplace negate float ${target.kind}")
                 }
             }
-            else -> throw AssemblyError("negate of invalid type")
+            else -> throw AssemblyError("negate of invalid type $dt")
         }
     }
 

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

@@ -0,0 +1,15 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<module type="JAVA_MODULE" version="4">
+  <component name="NewModuleRootManager" inherit-compiler-output="true">
+    <exclude-output />
+    <content url="file://$MODULE_DIR$">
+      <sourceFolder url="file://$MODULE_DIR$/src" isTestSource="false" />
+      <excludeFolder url="file://$MODULE_DIR$/build" />
+    </content>
+    <orderEntry type="inheritedJdk" />
+    <orderEntry type="sourceFolder" forTests="false" />
+    <orderEntry type="library" name="KotlinJavaRuntime" level="project" />
+    <orderEntry type="module" module-name="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

@@ -46,14 +46,14 @@ class ConstExprEvaluator {
                     left.number.toInt().ushr(amount.number.toInt())
                 else
                     left.number.toInt().shr(amount.number.toInt())
-        return NumericLiteralValue(left.type, result, left.position)
+        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, left.position)
+        return NumericLiteralValue(left.type, result.toDouble(), left.position)
     }
 
     private fun logicalxor(left: NumericLiteralValue, right: NumericLiteralValue): NumericLiteralValue {
@@ -61,12 +61,12 @@ class ConstExprEvaluator {
         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.toDouble() != 0.0), 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.toDouble() != 0.0) xor (right.number.toInt() != 0), left.position)
-                DataType.FLOAT -> NumericLiteralValue.fromBoolean((left.number.toDouble() != 0.0) xor (right.number.toDouble() != 0.0), left.position)
+                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)
@@ -78,12 +78,12 @@ class ConstExprEvaluator {
         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.toDouble() != 0.0, 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.toDouble() != 0.0 || right.number.toInt() != 0, left.position)
-                DataType.FLOAT -> NumericLiteralValue.fromBoolean(left.number.toDouble() != 0.0 || right.number.toDouble() != 0.0, left.position)
+                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)
@@ -95,12 +95,12 @@ class ConstExprEvaluator {
         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.toDouble() != 0.0, 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.toDouble() != 0.0 && right.number.toInt() != 0, left.position)
-                DataType.FLOAT -> NumericLiteralValue.fromBoolean(left.number.toDouble() != 0.0 && right.number.toDouble() != 0.0, left.position)
+                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)
@@ -110,11 +110,11 @@ class ConstExprEvaluator {
     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)).toShort(), left.position)
+                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(), left.position)
+                return NumericLiteralValue(DataType.UWORD, (left.number.toInt() xor right.number.toInt()).toDouble(), left.position)
             }
         }
         throw ExpressionError("cannot calculate $left ^ $right", left.position)
@@ -123,11 +123,11 @@ class ConstExprEvaluator {
     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)).toShort(), left.position)
+                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(), left.position)
+                return NumericLiteralValue(DataType.UWORD, (left.number.toInt() or right.number.toInt()).toDouble(), left.position)
             }
         }
         throw ExpressionError("cannot calculate $left | $right", left.position)
@@ -136,11 +136,11 @@ class ConstExprEvaluator {
     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)).toShort(), left.position)
+                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(), left.position)
+                return NumericLiteralValue(DataType.UWORD, (left.number.toInt() and right.number.toInt()).toDouble(), left.position)
             }
         }
         throw ExpressionError("cannot calculate $left & $right", left.position)
@@ -151,12 +151,12 @@ class ConstExprEvaluator {
         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.toDouble()), 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.toDouble().pow(right.number.toInt()), left.position)
-                DataType.FLOAT -> NumericLiteralValue(DataType.FLOAT, left.number.toDouble().pow(right.number.toDouble()), left.position)
+                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)
@@ -168,12 +168,12 @@ class ConstExprEvaluator {
         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.toDouble(), 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.toDouble() + right.number.toInt(), left.position)
-                DataType.FLOAT -> NumericLiteralValue(DataType.FLOAT, left.number.toDouble() + right.number.toDouble(), left.position)
+                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)
@@ -185,12 +185,12 @@ class ConstExprEvaluator {
         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.toDouble(), 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.toDouble() - right.number.toInt(), left.position)
-                DataType.FLOAT -> NumericLiteralValue(DataType.FLOAT, left.number.toDouble() - right.number.toDouble(), left.position)
+                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)
@@ -202,12 +202,12 @@ class ConstExprEvaluator {
         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.toDouble(), 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.toDouble() * right.number.toInt(), left.position)
-                DataType.FLOAT -> NumericLiteralValue(DataType.FLOAT, left.number.toDouble() * right.number.toDouble(), left.position)
+                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)
@@ -227,19 +227,19 @@ class ConstExprEvaluator {
                     NumericLiteralValue.optimalInteger(result, left.position)
                 }
                 DataType.FLOAT -> {
-                    if(right.number.toDouble()==0.0) divideByZeroError(right.position)
-                    NumericLiteralValue(DataType.FLOAT, left.number.toInt() / right.number.toDouble(), left.position)
+                    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.toDouble() / right.number.toInt(), left.position)
+                    NumericLiteralValue(DataType.FLOAT, left.number / right.number.toInt(), left.position)
                 }
                 DataType.FLOAT -> {
-                    if(right.number.toDouble()==0.0) divideByZeroError(right.position)
-                    NumericLiteralValue(DataType.FLOAT, left.number.toDouble() / right.number.toDouble(), left.position)
+                    if(right.number ==0.0) divideByZeroError(right.position)
+                    NumericLiteralValue(DataType.FLOAT, left.number / right.number, left.position)
                 }
                 else -> throw ExpressionError(error, left.position)
             }
@@ -256,19 +256,19 @@ class ConstExprEvaluator {
                     NumericLiteralValue.optimalNumeric(left.number.toInt().toDouble() % right.number.toInt().toDouble(), left.position)
                 }
                 DataType.FLOAT -> {
-                    if(right.number.toDouble()==0.0) divideByZeroError(right.position)
-                    NumericLiteralValue(DataType.FLOAT, left.number.toInt() % right.number.toDouble(), left.position)
+                    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.toDouble() % right.number.toInt(), left.position)
+                    NumericLiteralValue(DataType.FLOAT, left.number % right.number.toInt(), left.position)
                 }
                 DataType.FLOAT -> {
-                    if(right.number.toDouble()==0.0) divideByZeroError(right.position)
-                    NumericLiteralValue(DataType.FLOAT, left.number.toDouble() % right.number.toDouble(), left.position)
+                    if(right.number ==0.0) divideByZeroError(right.position)
+                    NumericLiteralValue(DataType.FLOAT, left.number % right.number, left.position)
                 }
                 else -> throw ExpressionError(error, left.position)
             }

codeOptimizers/src/prog8/optimizer/ConstantFoldingOptimizer.kt

@@ -12,7 +12,7 @@ import prog8.ast.walk.IAstModification
 import kotlin.math.pow
 
 
-internal class ConstantFoldingOptimizer(private val program: Program) : AstWalker() {
+class ConstantFoldingOptimizer(private val program: Program) : AstWalker() {
 
     override fun before(memread: DirectMemoryRead, parent: Node): Iterable<IAstModification> {
         // @( &thing )  -->  thing
@@ -23,6 +23,13 @@ internal class ConstantFoldingOptimizer(private val program: Program) : AstWalke
             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.
@@ -40,7 +47,7 @@ internal class ConstantFoldingOptimizer(private val program: Program) : AstWalke
                     }
                     DataType.FLOAT -> {
                         listOf(IAstModification.ReplaceNode(expr,
-                                NumericLiteralValue(DataType.FLOAT, -subexpr.number.toDouble(), subexpr.position),
+                                NumericLiteralValue(DataType.FLOAT, -subexpr.number, subexpr.position),
                                 parent))
                     }
                     else -> throw ExpressionError("can only take negative of int or float", subexpr.position)
@@ -48,29 +55,29 @@ internal class ConstantFoldingOptimizer(private val program: Program) : AstWalke
                 "~" -> when (subexpr.type) {
                     DataType.BYTE -> {
                         listOf(IAstModification.ReplaceNode(expr,
-                                NumericLiteralValue(DataType.BYTE, subexpr.number.toInt().inv(), subexpr.position),
+                                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, subexpr.position),
+                                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(), subexpr.position),
+                                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, subexpr.position),
+                                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.toDouble() == 0.0, subexpr.position),
+                            NumericLiteralValue.fromBoolean(subexpr.number == 0.0, subexpr.position),
                             parent))
                 }
                 else -> throw ExpressionError(expr.operator, subexpr.position)
@@ -79,7 +86,7 @@ internal class ConstantFoldingOptimizer(private val program: Program) : AstWalke
         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.
@@ -101,23 +108,50 @@ internal class ConstantFoldingOptimizer(private val program: Program) : AstWalke
         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.toDouble()) {
+            when (leftconst.number) {
                 0.0 -> {
-                    val value = NumericLiteralValue(leftDt, 0, expr.position)
+                    val value = NumericLiteralValue(leftDt, 0.0, expr.position)
                     modifications += IAstModification.ReplaceNode(expr, value, parent)
                 }
                 1.0 -> {
-                    val value = NumericLiteralValue(leftDt, 1, expr.position)
+                    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.toDouble()), expr.position)
+                        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)
@@ -128,7 +162,7 @@ internal class ConstantFoldingOptimizer(private val program: Program) : AstWalke
                                     is VarDecl -> parent.datatype
                                     else -> leftDt
                                 }
-                            val one = NumericLiteralValue(targetDt, 1, expr.position)
+                            val one = NumericLiteralValue(targetDt, 1.0, expr.position)
                             val shift = BinaryExpression(one, "<<", expr.right, expr.position)
                             modifications += IAstModification.ReplaceNode(expr, shift, parent)
                         }
@@ -159,13 +193,94 @@ internal class ConstantFoldingOptimizer(private val program: Program) : AstWalke
             }
         }
 
+        val evaluator = ConstExprEvaluator()
+
         // const fold when both operands are a const
         if(leftconst != null && rightconst != null) {
-            val evaluator = ConstExprEvaluator()
             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
     }
 
@@ -195,17 +310,17 @@ internal class ConstantFoldingOptimizer(private val program: Program) : AstWalke
         return noModifications
     }
 
-    override fun after(functionCall: FunctionCall, parent: Node): Iterable<IAstModification> {
+    override fun after(functionCallExpr: FunctionCallExpression, parent: Node): Iterable<IAstModification> {
         // the args of a fuction are constfolded via recursion already.
-        val constvalue = functionCall.constValue(program)
+        val constvalue = functionCallExpr.constValue(program)
         return if(constvalue!=null)
-            listOf(IAstModification.ReplaceNode(functionCall, constvalue, parent))
+            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: RangeExpr): RangeExpr? {
+        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)
@@ -222,11 +337,11 @@ internal class ConstantFoldingOptimizer(private val program: Program) : AstWalke
                     range.step
                 }
 
-            return RangeExpr(fromCast.valueOrZero(), toCast.valueOrZero(), newStep, range.position)
+            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? RangeExpr ?: return noModifications
+        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
@@ -312,12 +427,12 @@ internal class ConstantFoldingOptimizer(private val program: Program) : AstWalke
     {
         // NOTE: THIS IS ONLY VALID ON FLOATING POINT CONSTANTS
 
-        // todo: this implements only a small set of possible reorderings at this time
+        // todo: this implements only a small set of possible reorderings at this time, we could think of more
         if(expr.operator==subExpr.operator) {
             // both operators are the same.
 
             // If associative,  we can simply shuffle the const operands around to optimize.
-            if(expr.operator in associativeOperators) {
+            if(expr.operator in AssociativeOperators) {
                 return if(leftIsConst) {
                     if(subleftIsConst)
                         ShuffleOperands(expr, null, subExpr, subExpr.right, null, null, expr.left)

codeOptimizers/src/prog8/optimizer/ConstantIdentifierReplacer.kt

@@ -1,6 +1,5 @@
 package prog8.optimizer
 
-import prog8.ast.INameScope
 import prog8.ast.Node
 import prog8.ast.Program
 import prog8.ast.base.*
@@ -8,58 +7,43 @@ import prog8.ast.expressions.*
 import prog8.ast.statements.*
 import prog8.ast.walk.AstWalker
 import prog8.ast.walk.IAstModification
-import prog8.compiler.IErrorReporter
-import prog8.compiler.astprocessing.size
-import prog8.compiler.astprocessing.toConstantIntegerRange
-import prog8.compiler.target.ICompilationTarget
+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)
-internal class VarConstantValueTypeAdjuster(private val program: Program, private val errors: IErrorReporter) : AstWalker() {
+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.inferType(program) isnot decl.datatype) {
-                // 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))
+                && 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)
         }
 
-        // move vardecl to the containing subroutine and add initialization assignment in its place if needed
-        if(decl.type == VarDeclType.VAR && decl.datatype in NumericDatatypes) {
-            val subroutine = decl.definingSubroutine as? INameScope
-            if(subroutine!=null && subroutine!==parent) {
-                val declValue = decl.value
-                decl.value = null
-                decl.allowInitializeWithZero = false
-                return if (declValue == null) {
-                    listOf(
-                        IAstModification.Remove(decl, parent as INameScope),
-                        IAstModification.InsertFirst(decl, subroutine)
-                    )
-                } else {
-                    val target = AssignTarget(IdentifierReference(listOf(decl.name), decl.position), null, null, decl.position)
-                    val assign = Assignment(target, declValue, decl.position)
-                    listOf(
-                        IAstModification.ReplaceNode(decl, assign, parent),
-                        IAstModification.InsertFirst(decl, subroutine)
-                    )
-                }
-            }
-        }
         return noModifications
     }
 
-    override fun after(range: RangeExpr, parent: Node): Iterable<IAstModification> {
-        val from = range.from.constValue(program)?.number?.toDouble()
-        val to = range.to.constValue(program)?.number?.toDouble()
-        val step = range.step.constValue(program)?.number?.toDouble()
+    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)
@@ -124,8 +108,7 @@ internal class ConstantIdentifierReplacer(private val program: Program, private
 
     override fun before(decl: VarDecl, parent: Node): Iterable<IAstModification> {
         // the initializer value can't refer to the variable itself (recursive definition)
-        // TODO: use call graph for this?
-        if(decl.value?.referencesIdentifier(decl.name) == true || decl.arraysize?.indexExpr?.referencesIdentifier(decl.name) == true) {
+        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
         }
@@ -151,27 +134,27 @@ internal class ConstantIdentifierReplacer(private val program: Program, private
                     // 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.toDouble(), litval.position)
+                        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? RangeExpr
+                    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(compTarget))
-                            errors.err("range expression size doesn't match declared array size", decl.value?.position!!)
-                        val constRange = rangeExpr.toConstantIntegerRange(compTarget)
+                        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.toShort(), decl.value!!.position) }.toTypedArray(),
+                                        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, decl.value!!.position) }.toTypedArray(),
+                                        constRange.map { NumericLiteralValue(eltType, it.toDouble(), decl.value!!.position) }.toTypedArray(),
                                         position = decl.value!!.position)
                             }
                             return listOf(IAstModification.ReplaceNode(decl.value!!, newValue, decl))
@@ -204,19 +187,19 @@ internal class ConstantIdentifierReplacer(private val program: Program, private
                             else -> {}
                         }
                         // create the array itself, filled with the fillvalue.
-                        val array = Array(size) {fillvalue}.map { NumericLiteralValue(ArrayToElementTypes.getValue(decl.datatype), it, numericLv.position) }.toTypedArray<Expression>()
+                        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? RangeExpr
+                    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(compTarget))
-                            errors.err("range expression size (${rangeExpr.size(compTarget)}) doesn't match declared array size ($declArraySize)", decl.value?.position!!)
-                        val constRange = rangeExpr.toConstantIntegerRange(compTarget)
+                        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(),
@@ -229,7 +212,7 @@ internal class ConstantIdentifierReplacer(private val program: Program, private
                     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.toDouble()
+                        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 {

codeOptimizers/src/prog8/optimizer/ExpressionSimplifier.kt

@@ -1,5 +1,6 @@
 package prog8.optimizer
 
+import prog8.ast.IStatementContainer
 import prog8.ast.Node
 import prog8.ast.Program
 import prog8.ast.base.DataType
@@ -7,22 +8,23 @@ import prog8.ast.base.FatalAstException
 import prog8.ast.base.IntegerDatatypes
 import prog8.ast.base.NumericDatatypes
 import prog8.ast.expressions.*
-import prog8.ast.statements.Assignment
+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 expression optimizations
+    todo add more peephole expression optimizations
 
     Investigate what optimizations binaryen has, also see  https://egorbo.com/peephole-optimizations.html
 
  */
 
 
-internal class ExpressionSimplifier(private val program: Program) : AstWalker() {
+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()
 
@@ -54,35 +56,26 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
         return mods
     }
 
-    override fun before(expr: PrefixExpression, parent: Node): Iterable<IAstModification> {
-        if (expr.operator == "+") {
-            // +X --> X
-            return listOf(IAstModification.ReplaceNode(expr, expr.expression, parent))
-        } else if (expr.operator == "not") {
-            when(expr.expression) {
-                is PrefixExpression -> {
-                    // NOT(NOT(...)) -> ...
-                    val pe = expr.expression as PrefixExpression
-                    if(pe.operator == "not")
-                        return listOf(IAstModification.ReplaceNode(expr, pe.expression, parent))
+    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)
+                    )
                 }
-                is BinaryExpression -> {
-                    // NOT (xxxx)  ->   invert the xxxx
-                    val be = expr.expression as BinaryExpression
-                    val newExpr = when (be.operator) {
-                        "<" -> BinaryExpression(be.left, ">=", be.right, be.position)
-                        ">" -> BinaryExpression(be.left, "<=", be.right, be.position)
-                        "<=" -> BinaryExpression(be.left, ">", be.right, be.position)
-                        ">=" -> BinaryExpression(be.left, "<", be.right, be.position)
-                        "==" -> BinaryExpression(be.left, "!=", be.right, be.position)
-                        "!=" -> BinaryExpression(be.left, "==", be.right, be.position)
-                        else -> null
-                    }
-
-                    if (newExpr != null)
-                        return listOf(IAstModification.ReplaceNode(expr, newExpr, parent))
-                }
-                else -> return noModifications
             }
         }
         return noModifications
@@ -98,11 +91,11 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
             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)
+        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 (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))
         }
@@ -149,7 +142,7 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
                     val x = expr.right
                     val y = determineY(x, leftBinExpr)
                     if (y != null) {
-                        val yPlus1 = BinaryExpression(y, "+", NumericLiteralValue(leftDt, 1, y.position), y.position)
+                        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))
                     }
@@ -159,7 +152,7 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
                     val x = expr.right
                     val y = determineY(x, leftBinExpr)
                     if (y != null) {
-                        val yMinus1 = BinaryExpression(y, "-", NumericLiteralValue(leftDt, 1, y.position), y.position)
+                        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))
                     }
@@ -179,40 +172,30 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
             }
         }
 
-        if(expr.operator == ">=" && rightVal?.number == 0) {
+        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(expr.operator == "<" && rightVal?.number == 0) {
+        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))
             }
-            when(leftDt) {
-                DataType.BYTE -> {
-                    // signed < 0  -->  signed & $80
-                    return listOf(IAstModification.ReplaceNode(
-                            expr,
-                            BinaryExpression(expr.left, "&", NumericLiteralValue.optimalInteger(0x80, expr.position), expr.position),
-                            parent
-                    ))
-                }
-                DataType.WORD -> {
-                    // signedw < 0 -->  msb(signedw) & $80
-                    return listOf(IAstModification.ReplaceNode(
-                            expr,
-                            BinaryExpression(FunctionCall(IdentifierReference(listOf("msb"), expr.position),
-                                    mutableListOf(expr.left),
-                                    expr.position
-                            ), "&", NumericLiteralValue.optimalInteger(0x80, expr.position), expr.position),
-                            parent
-                    ))
-                }
-                else -> {}
-            }
         }
 
         // simplify when a term is constant and directly determines the outcome
@@ -220,52 +203,62 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
         val constFalse = NumericLiteralValue.fromBoolean(false, expr.position)
         val newExpr: Expression? = when (expr.operator) {
             "or" -> {
-                if ((leftVal != null && leftVal.asBooleanValue) || (rightVal != null && rightVal.asBooleanValue))
-                    constTrue
-                else if (leftVal != null && !leftVal.asBooleanValue)
-                    expr.right
-                else if (rightVal != null && !rightVal.asBooleanValue)
-                    expr.left
-                else
-                    null
+                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" -> {
-                if ((leftVal != null && !leftVal.asBooleanValue) || (rightVal != null && !rightVal.asBooleanValue))
-                    constFalse
-                else if (leftVal != null && leftVal.asBooleanValue)
-                    expr.right
-                else if (rightVal != null && rightVal.asBooleanValue)
-                    expr.left
-                else
-                    null
+                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" -> {
-                if (leftVal != null && !leftVal.asBooleanValue)
-                    expr.right
-                else if (rightVal != null && !rightVal.asBooleanValue)
-                    expr.left
-                else if (leftVal != null && leftVal.asBooleanValue)
-                    PrefixExpression("not", expr.right, expr.right.position)
-                else if (rightVal != null && rightVal.asBooleanValue)
-                    PrefixExpression("not", expr.left, expr.left.position)
-                else
-                    null
+                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
+                }
             }
-            "|", "^" -> {
-                if (leftVal != null && !leftVal.asBooleanValue)
-                    expr.right
-                else if (rightVal != null && !rightVal.asBooleanValue)
-                    expr.left
-                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
+                }
             }
             "&" -> {
-                if (leftVal != null && !leftVal.asBooleanValue)
-                    constFalse
-                else if (rightVal != null && !rightVal.asBooleanValue)
-                    constFalse
-                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)
@@ -284,32 +277,32 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
         return noModifications
     }
 
-    override fun after(functionCall: FunctionCall, parent: Node): Iterable<IAstModification> {
-        if(functionCall.target.nameInSource == listOf("lsb")) {
-            val arg = functionCall.args[0]
+    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(functionCall, arg.expression, parent))
+                    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(functionCall, arg, parent))
+                    return listOf(IAstModification.ReplaceNode(functionCallExpr, arg, parent))
                 }
             }
         }
-        else if(functionCall.target.nameInSource == listOf("msb")) {
-            val arg = functionCall.args[0]
+        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(
-                            functionCall,
-                            NumericLiteralValue(valueDt.getOr(DataType.UBYTE), 0, arg.expression.position),
+                            functionCallExpr,
+                            NumericLiteralValue(valueDt.getOr(DataType.UBYTE), 0.0, arg.expression.position),
                             parent))
                 }
             } else {
@@ -317,8 +310,8 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
                 if (argDt istype DataType.BYTE || argDt istype DataType.UBYTE) {
                     // useless msb() of byte value, replace with 0
                     return listOf(IAstModification.ReplaceNode(
-                            functionCall,
-                            NumericLiteralValue(argDt.getOr(DataType.UBYTE), 0, arg.position),
+                            functionCallExpr,
+                            NumericLiteralValue(argDt.getOr(DataType.UBYTE), 0.0, arg.position),
                             parent))
                 }
             }
@@ -327,6 +320,63 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
         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
@@ -351,7 +401,7 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
         if (rightVal2 != null) {
             // right value is a constant, see if we can optimize
             val rightConst: NumericLiteralValue = rightVal2
-            when (rightConst.number.toDouble()) {
+            when (rightConst.number) {
                 0.0 -> {
                     // left
                     return expr2.left
@@ -360,7 +410,7 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
         }
         // no need to check for left val constant (because of associativity)
 
-        val rnum = rightVal?.number?.toDouble()
+        val rnum = rightVal?.number
         if(rnum!=null && rnum<0.0) {
             expr.operator = "-"
             expr.right = NumericLiteralValue(rightVal.type, -rnum, rightVal.position)
@@ -381,7 +431,7 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
 
         if (rightVal != null) {
             // right value is a constant, see if we can optimize
-            val rnum = rightVal.number.toDouble()
+            val rnum = rightVal.number
             if (rnum == 0.0) {
                 // left
                 return expr.left
@@ -395,7 +445,7 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
         }
         if (leftVal != null) {
             // left value is a constant, see if we can optimize
-            when (leftVal.number.toDouble()) {
+            when (leftVal.number) {
                 0.0 -> {
                     // -right
                     return PrefixExpression("-", expr.right, expr.position)
@@ -414,7 +464,7 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
         if (rightVal != null) {
             // right value is a constant, see if we can optimize
             val rightConst: NumericLiteralValue = rightVal
-            when (rightConst.number.toDouble()) {
+            when (rightConst.number) {
                 -3.0 -> {
                     // -1/(left*left*left)
                     return BinaryExpression(NumericLiteralValue(DataType.FLOAT, -1.0, expr.position), "/",
@@ -434,11 +484,11 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
                 }
                 0.0 -> {
                     // 1
-                    return NumericLiteralValue(rightConst.type, 1, expr.position)
+                    return NumericLiteralValue(rightConst.type, 1.0, expr.position)
                 }
                 0.5 -> {
                     // sqrt(left)
-                    return FunctionCall(IdentifierReference(listOf("sqrt"), expr.position), mutableListOf(expr.left), expr.position)
+                    return FunctionCallExpression(IdentifierReference(listOf("sqrt"), expr.position), mutableListOf(expr.left), expr.position)
                 }
                 1.0 -> {
                     // left
@@ -456,18 +506,18 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
         }
         if (leftVal != null) {
             // left value is a constant, see if we can optimize
-            when (leftVal.number.toDouble()) {
+            when (leftVal.number) {
                 -1.0 -> {
                     // -1
                     return NumericLiteralValue(DataType.FLOAT, -1.0, expr.position)
                 }
                 0.0 -> {
                     // 0
-                    return NumericLiteralValue(leftVal.type, 0, expr.position)
+                    return NumericLiteralValue(leftVal.type, 0.0, expr.position)
                 }
                 1.0 -> {
                     //1
-                    return NumericLiteralValue(leftVal.type, 1, expr.position)
+                    return NumericLiteralValue(leftVal.type, 1.0, expr.position)
                 }
 
             }
@@ -489,7 +539,7 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
                     val idt = expr.inferType(program)
                     if(!idt.isKnown)
                         throw FatalAstException("unknown dt")
-                    return NumericLiteralValue(idt.getOr(DataType.UNDEFINED), 0, expr.position)
+                    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)
@@ -509,7 +559,7 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
         if (rightVal != null) {
             // right value is a constant, see if we can optimize
             val rightConst: NumericLiteralValue = rightVal
-            val cv = rightConst.number.toDouble()
+            val cv = rightConst.number
             val leftIDt = expr.left.inferType(program)
             if (!leftIDt.isKnown)
                 return null
@@ -544,22 +594,22 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
             }
 
             if (leftDt == DataType.UBYTE) {
-                if (abs(rightConst.number.toDouble()) >= 256.0) {
-                    return NumericLiteralValue(DataType.UBYTE, 0, expr.position)
+                if (abs(rightConst.number) >= 256.0) {
+                    return NumericLiteralValue(DataType.UBYTE, 0.0, expr.position)
                 }
             } else if (leftDt == DataType.UWORD) {
-                if (abs(rightConst.number.toDouble()) >= 65536.0) {
-                    return NumericLiteralValue(DataType.UBYTE, 0, expr.position)
+                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.toDouble()) {
+            when (leftVal.number) {
                 0.0 -> {
                     // 0
-                    return NumericLiteralValue(leftVal.type, 0, expr.position)
+                    return NumericLiteralValue(leftVal.type, 0.0, expr.position)
                 }
             }
         }
@@ -576,14 +626,14 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
             // right value is a constant, see if we can optimize
             val leftValue: Expression = expr2.left
             val rightConst: NumericLiteralValue = rightVal2
-            when (val cv = rightConst.number.toDouble()) {
+            when (val cv = rightConst.number) {
                 -1.0 -> {
                     // -left
                     return PrefixExpression("-", leftValue, expr.position)
                 }
                 0.0 -> {
                     // 0
-                    return NumericLiteralValue(rightConst.type, 0, expr.position)
+                    return NumericLiteralValue(rightConst.type, 0.0, expr.position)
                 }
                 1.0 -> {
                     // left
@@ -624,19 +674,19 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
         when (val targetDt = targetIDt.getOr(DataType.UNDEFINED)) {
             DataType.UBYTE, DataType.BYTE -> {
                 if (amount >= 8) {
-                    return NumericLiteralValue(targetDt, 0, expr.position)
+                    return NumericLiteralValue(targetDt, 0.0, expr.position)
                 }
             }
             DataType.UWORD, DataType.WORD -> {
                 if (amount >= 16) {
-                    return NumericLiteralValue(targetDt, 0, expr.position)
+                    return NumericLiteralValue(targetDt, 0.0, expr.position)
                 } else if (amount >= 8) {
-                    val lsb = FunctionCall(IdentifierReference(listOf("lsb"), expr.position), mutableListOf(expr.left), expr.position)
+                    val lsb = FunctionCallExpression(IdentifierReference(listOf("lsb"), expr.position), mutableListOf(expr.left), expr.position)
                     if (amount == 8) {
-                        return FunctionCall(IdentifierReference(listOf("mkword"), expr.position), mutableListOf(lsb, NumericLiteralValue.optimalInteger(0, expr.position)), expr.position)
+                        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 FunctionCall(IdentifierReference(listOf("mkword"), expr.position), mutableListOf(shifted, NumericLiteralValue.optimalInteger(0, expr.position)), expr.position)
+                    return FunctionCallExpression(IdentifierReference(listOf("mkword"), expr.position), mutableListOf(shifted, NumericLiteralValue.optimalInteger(0, expr.position)), expr.position)
                 }
             }
             else -> {
@@ -673,11 +723,11 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
                     return NumericLiteralValue.optimalInteger(0, expr.position)
                 }
                 else if (amount >= 8) {
-                    val msb = FunctionCall(IdentifierReference(listOf("msb"), expr.position), mutableListOf(expr.left), expr.position)
+                    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, expr.position)
-                        return FunctionCall(IdentifierReference(listOf("mkword"), expr.position), mutableListOf(zero, msb), expr.position)
+                        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)
                 }
@@ -695,7 +745,7 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
     }
 
     private fun reorderAssociativeWithConstant(expr: BinaryExpression, leftVal: NumericLiteralValue?): BinExprWithConstants {
-        if (expr.operator in associativeOperators && leftVal != null) {
+        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
@@ -707,4 +757,4 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
 
     private data class BinExprWithConstants(val expr: BinaryExpression, val leftVal: NumericLiteralValue?, val rightVal: NumericLiteralValue?)
 
-}
+}

codeOptimizers/src/prog8/optimizer/Extensions.kt

@@ -2,11 +2,15 @@ package prog8.optimizer
 
 import prog8.ast.IBuiltinFunctions
 import prog8.ast.Program
-import prog8.compiler.IErrorReporter
-import prog8.compiler.target.ICompilationTarget
+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
 
 
-internal fun Program.constantFold(errors: IErrorReporter, compTarget: ICompilationTarget) {
+fun Program.constantFold(errors: IErrorReporter, compTarget: ICompilationTarget) {
     val valuetypefixer = VarConstantValueTypeAdjuster(this, errors)
     valuetypefixer.visit(this)
     if(errors.noErrors()) {
@@ -40,9 +44,10 @@ internal fun Program.constantFold(errors: IErrorReporter, compTarget: ICompilati
 }
 
 
-internal fun Program.optimizeStatements(errors: IErrorReporter,
-                                        functions: IBuiltinFunctions,
-                                        compTarget: ICompilationTarget): Int {
+fun Program.optimizeStatements(errors: IErrorReporter,
+                               functions: IBuiltinFunctions,
+                               compTarget: ICompilationTarget
+): Int {
     val optimizer = StatementOptimizer(this, errors, functions, compTarget)
     optimizer.visit(this)
     val optimizationCount = optimizer.applyModifications()
@@ -52,14 +57,26 @@ internal fun Program.optimizeStatements(errors: IErrorReporter,
     return optimizationCount
 }
 
-internal fun Program.simplifyExpressions() : Int {
-    val opti = ExpressionSimplifier(this)
+fun Program.simplifyExpressions(errors: IErrorReporter) : Int {
+    val opti = ExpressionSimplifier(this, errors)
     opti.visit(this)
     return opti.applyModifications()
 }
 
-internal fun Program.splitBinaryExpressions(compTarget: ICompilationTarget) : Int {
-    val opti = BinExprSplitter(this, compTarget)
+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

@@ -1,55 +1,38 @@
 package prog8.optimizer
 
-import prog8.ast.IBuiltinFunctions
-import prog8.ast.INameScope
-import prog8.ast.Node
-import prog8.ast.Program
+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.ast.walk.IAstVisitor
-import prog8.compiler.IErrorReporter
-import prog8.compiler.astprocessing.size
-import prog8.compiler.target.ICompilationTarget
+import prog8.compilerinterface.ICompilationTarget
+import prog8.compilerinterface.IErrorReporter
 import kotlin.math.floor
 
-internal const val retvarName = "prog8_retval"
 
-
-internal class StatementOptimizer(private val program: Program,
+class StatementOptimizer(private val program: Program,
                                   private val errors: IErrorReporter,
                                   private val functions: IBuiltinFunctions,
-                                  private val compTarget: ICompilationTarget) : AstWalker() {
+                                  private val compTarget: ICompilationTarget
+) : AstWalker() {
 
-    private val subsThatNeedReturnVariable = mutableSetOf<Triple<INameScope, DataType, Position>>()
-
-
-    override fun after(subroutine: Subroutine, parent: Node): Iterable<IAstModification> {
-        for(returnvar in subsThatNeedReturnVariable) {
-            val decl = VarDecl(VarDeclType.VAR, returnvar.second, ZeropageWish.DONTCARE, null, retvarName, null,
-                isArray = false,
-                autogeneratedDontRemove = true,
-                sharedWithAsm = false,
-                position = returnvar.third
-            )
-            returnvar.first.statements.add(0, decl)
-        }
-        subsThatNeedReturnVariable.clear()
-        return noModifications
-    }
-
-    override fun before(functionCall: FunctionCall, parent: Node): Iterable<IAstModification> {
+    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.
-        val subroutine = functionCall.target.targetSubroutine(program)
+
+        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, subroutine)
+                        val scoped = scopePrefix(orig.identifier)
                         AddressOf(scoped, orig.position)
                     }
                     is DirectMemoryRead -> {
@@ -58,28 +41,25 @@ internal class StatementOptimizer(private val program: Program,
                             else -> return noModifications
                         }
                     }
-                    is IdentifierReference -> scopePrefix(orig, subroutine)
+                    is IdentifierReference -> scopePrefix(orig)
                     is NumericLiteralValue -> orig.copy()
                     is StringLiteralValue -> orig.copy()
                     else -> return noModifications
                 }
-                return listOf(IAstModification.ReplaceNode(functionCall, copy, parent))
+                return listOf(IAstModification.ReplaceNode(functionCallExpr, copy, parent))
             }
         }
         return noModifications
     }
 
-    private fun scopePrefix(variable: IdentifierReference, subroutine: Subroutine): IdentifierReference {
-        val scoped = subroutine.makeScopedName(variable.nameInSource.last())
-        return IdentifierReference(scoped.split('.'), variable.position)
-    }
+
 
     override fun after(functionCallStatement: FunctionCallStatement, parent: Node): Iterable<IAstModification> {
-        if(functionCallStatement.target.nameInSource.size==1 && functionCallStatement.target.nameInSource[0] in functions.names) {
+        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, functionCallStatement.definingScope))
+                return listOf(IAstModification.Remove(functionCallStatement, parent as IStatementContainer))
             }
         }
 
@@ -97,27 +77,27 @@ internal class StatementOptimizer(private val program: Program,
                 if(string!=null) {
                     val pos = functionCallStatement.position
                     if (string.value.length == 1) {
-                        val firstCharEncoded = compTarget.encodeString(string.value, string.altEncoding)[0]
+                        val firstCharEncoded = compTarget.encodeString(string.value, string.encoding)[0]
                         val chrout = FunctionCallStatement(
                             IdentifierReference(listOf("txt", "chrout"), pos),
-                            mutableListOf(NumericLiteralValue(DataType.UBYTE, firstCharEncoded.toInt(), 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.altEncoding)
+                        val firstTwoCharsEncoded = compTarget.encodeString(string.value.take(2), string.encoding)
                         val chrout1 = FunctionCallStatement(
                             IdentifierReference(listOf("txt", "chrout"), pos),
-                            mutableListOf(NumericLiteralValue(DataType.UBYTE, firstTwoCharsEncoded[0].toInt(), 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].toInt(), pos)),
+                            mutableListOf(NumericLiteralValue(DataType.UBYTE, firstTwoCharsEncoded[1].toDouble(), pos)),
                             functionCallStatement.void, pos
                         )
                         return listOf(
-                            IAstModification.InsertBefore(functionCallStatement, chrout1, parent as INameScope),
+                            IAstModification.InsertBefore(functionCallStatement, chrout1, parent as IStatementContainer),
                             IAstModification.ReplaceNode(functionCallStatement, chrout2, parent)
                         )
                     }
@@ -130,53 +110,55 @@ internal class StatementOptimizer(private val program: 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, functionCallStatement.definingScope))
+                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 before(functionCall: FunctionCall, parent: Node): Iterable<IAstModification> {
-//        // if the first instruction in the called subroutine is a return statement with constant value, replace with the constant value
-//        val subroutine = functionCall.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!=null) {
-//                val constval = first.value?.constValue(program)
-//                if(constval!=null)
-//                    return listOf(IAstModification.ReplaceNode(functionCall, constval, parent))
-//            }
-//        }
-//        return noModifications
-//    }
-
-    override fun after(ifStatement: IfStatement, parent: Node): Iterable<IAstModification> {
+    override fun after(ifElse: IfElse, parent: Node): Iterable<IAstModification> {
         // remove empty if statements
-        if(ifStatement.truepart.containsNoCodeNorVars && ifStatement.elsepart.containsNoCodeNorVars)
-            return listOf(IAstModification.Remove(ifStatement, ifStatement.definingScope))
+        if(ifElse.truepart.isEmpty() && ifElse.elsepart.isEmpty())
+            return listOf(IAstModification.Remove(ifElse, parent as IStatementContainer))
 
         // empty true part? switch with the else part
-        if(ifStatement.truepart.containsNoCodeNorVars && ifStatement.elsepart.containsCodeOrVars) {
-            val invertedCondition = PrefixExpression("not", ifStatement.condition, ifStatement.condition.position)
-            val emptyscope = AnonymousScope(mutableListOf(), ifStatement.elsepart.position)
-            val truepart = AnonymousScope(ifStatement.elsepart.statements, ifStatement.truepart.position)
+        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(ifStatement.condition, invertedCondition, ifStatement),
-                    IAstModification.ReplaceNode(ifStatement.truepart, truepart, ifStatement),
-                    IAstModification.ReplaceNode(ifStatement.elsepart, emptyscope, ifStatement)
+                    IAstModification.ReplaceNode(ifElse.condition, invertedCondition, ifElse),
+                    IAstModification.ReplaceNode(ifElse.truepart, truepart, ifElse),
+                    IAstModification.ReplaceNode(ifElse.elsepart, emptyscope, ifElse)
             )
         }
 
-        val constvalue = ifStatement.condition.constValue(program)
+        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", ifStatement.position)
-                listOf(IAstModification.ReplaceNode(ifStatement, ifStatement.truepart, parent))
+                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", ifStatement.position)
-                listOf(IAstModification.ReplaceNode(ifStatement, ifStatement.elsepart, parent))
+                errors.warn("condition is always false", ifElse.condition.position)
+                listOf(IAstModification.ReplaceNode(ifElse, ifElse.elsepart, parent))
             }
         }
 
@@ -184,24 +166,24 @@ internal class StatementOptimizer(private val program: Program,
     }
 
     override fun after(forLoop: ForLoop, parent: Node): Iterable<IAstModification> {
-        if(forLoop.body.containsNoCodeNorVars) {
+        if(forLoop.body.isEmpty()) {
             errors.warn("removing empty for loop", forLoop.position)
-            return listOf(IAstModification.Remove(forLoop, forLoop.definingScope))
+            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, forLoop.definingScope))
+                return listOf(IAstModification.Remove(forLoop, parent as IStatementContainer))
             }
         }
 
-        val range = forLoop.iterable as? RangeExpr
+        val range = forLoop.iterable as? RangeExpression
         if(range!=null) {
-            if (range.size(compTarget) == 1) {
+            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, 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))
             }
@@ -213,10 +195,10 @@ internal class StatementOptimizer(private val program: Program,
                 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.altEncoding)[0]
-                    val byte = NumericLiteralValue(DataType.UBYTE, character, iterable.position)
+                    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, 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))
                 }
@@ -230,7 +212,7 @@ internal class StatementOptimizer(private val program: Program,
                         val scope = AnonymousScope(mutableListOf(), forLoop.position)
                         scope.statements.add(Assignment(
                                 AssignTarget(forLoop.loopVar, null, null, forLoop.position), NumericLiteralValue.optimalInteger(av.toInt(), iterable.position),
-                                forLoop.position))
+                                AssignmentOrigin.OPTIMIZER, forLoop.position))
                         scope.statements.addAll(forLoop.body.statements)
                         return listOf(IAstModification.ReplaceNode(forLoop, scope, parent))
                     }
@@ -244,15 +226,14 @@ internal class StatementOptimizer(private val program: Program,
     override fun before(untilLoop: UntilLoop, parent: Node): Iterable<IAstModification> {
         val constvalue = untilLoop.condition.constValue(program)
         if(constvalue!=null) {
-            if(constvalue.asBooleanValue) {
-                // always true -> keep only the statement block (if there are no break statements)
+            return if(constvalue.asBooleanValue) {
+                // always true -> keep only the statement block
                 errors.warn("condition is always true", untilLoop.condition.position)
-                if(!hasBreak(untilLoop.body))
-                    return listOf(IAstModification.ReplaceNode(untilLoop, untilLoop.body, parent))
+                listOf(IAstModification.ReplaceNode(untilLoop, untilLoop.body, parent))
             } else {
                 // always false
                 val forever = RepeatLoop(null, untilLoop.body, untilLoop.position)
-                return listOf(IAstModification.ReplaceNode(untilLoop, forever, parent))
+                listOf(IAstModification.ReplaceNode(untilLoop, forever, parent))
             }
         }
         return noModifications
@@ -268,7 +249,7 @@ internal class StatementOptimizer(private val program: Program,
             } else {
                 // always false -> remove the while statement altogether
                 errors.warn("condition is always false", whileLoop.condition.position)
-                listOf(IAstModification.Remove(whileLoop, whileLoop.definingScope))
+                listOf(IAstModification.Remove(whileLoop, parent as IStatementContainer))
             }
         }
         return noModifications
@@ -277,14 +258,14 @@ internal class StatementOptimizer(private val program: Program,
     override fun after(repeatLoop: RepeatLoop, parent: Node): Iterable<IAstModification> {
         val iter = repeatLoop.iterations
         if(iter!=null) {
-            if(repeatLoop.body.containsNoCodeNorVars) {
+            if(repeatLoop.body.isEmpty()) {
                 errors.warn("empty loop removed", repeatLoop.position)
-                return listOf(IAstModification.Remove(repeatLoop, repeatLoop.definingScope))
+                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, repeatLoop.definingScope))
+                return listOf(IAstModification.Remove(repeatLoop, parent as IStatementContainer))
             }
             if (iterations == 1) {
                 errors.warn("iterations is always 1", iter.position)
@@ -294,13 +275,22 @@ internal class StatementOptimizer(private val program: Program,
         return noModifications
     }
 
-    override fun after(jump: Jump, parent: Node): Iterable<IAstModification> {
-        // if the jump is to the next statement, remove the jump
-        val scope = jump.definingScope
-        val label = jump.identifier?.targetStatement(program)
-        if(label!=null && scope.statements.indexOf(label) == scope.statements.indexOf(jump)+1)
-            return listOf(IAstModification.Remove(jump, jump.definingScope))
 
+    // 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
     }
 
@@ -314,7 +304,7 @@ internal class StatementOptimizer(private val program: Program,
                     val op1 = binExpr.operator
                     val op2 = rExpr.operator
 
-                    if(rExpr.left is NumericLiteralValue && op2 in associativeOperators) {
+                    if(rExpr.left is NumericLiteralValue && op2 in AssociativeOperators) {
                         // associative operator, make sure the constant numeric value is second (right)
                         return listOf(IAstModification.SwapOperands(rExpr))
                     }
@@ -323,34 +313,34 @@ internal class StatementOptimizer(private val program: Program,
                     if(rNum!=null) {
                         if (op1 == "+" || op1 == "-") {
                             if (op2 == "+") {
-                                // A = A +/- B + N
+                                // 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,
-                                        BinaryExpression(binExpr.left, "+", rExpr.right, rExpr.position),
-                                        assignment.position
+                                        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, assignment.definingScope))
+                                        IAstModification.InsertAfter(assignment, addConstant, parent as IStatementContainer))
                             } else if (op2 == "-") {
-                                // A = A +/- B - N
+                                // 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,
-                                        BinaryExpression(binExpr.left, "-", rExpr.right, rExpr.position),
-                                        assignment.position
+                                        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, assignment.definingScope))
+                                        IAstModification.InsertAfter(assignment, subConstant, parent as IStatementContainer))
                             }
                         }
                     }
                 }
             }
 
-            if(binExpr.operator in associativeOperators && binExpr.right isSameAs assignment.target) {
+            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))
@@ -365,27 +355,39 @@ internal class StatementOptimizer(private val program: Program,
     override fun after(assignment: Assignment, parent: Node): Iterable<IAstModification> {
         if(assignment.target isSameAs assignment.value) {
             // remove assignment to self
-            return listOf(IAstModification.Remove(assignment, assignment.definingScope))
+            return listOf(IAstModification.Remove(assignment, parent as IStatementContainer))
         }
 
         val targetIDt = assignment.target.inferType(program)
         if(!targetIDt.isKnown)
-            throw FatalAstException("can't infer type of assignment target")
+            return noModifications
 
         // optimize binary expressions a bit
-        val targetDt = targetIDt.getOr(DataType.UNDEFINED)
         val bexpr=assignment.value as? BinaryExpression
         if(bexpr!=null) {
-            val rightCv = bexpr.right.constValue(program)?.number?.toDouble()
+            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, assignment.definingScope))
+                            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)
@@ -393,13 +395,13 @@ internal class StatementOptimizer(private val program: Program,
                                 repeat(rightCv.toInt()) {
                                     incs.statements.add(PostIncrDecr(assignment.target.copy(), "++", assignment.position))
                                 }
-                                return listOf(IAstModification.ReplaceNode(assignment, incs, parent))
+                                listOf(IAstModification.ReplaceNode(assignment, if(incs.statements.size==1) incs.statements[0] else incs, parent))
                             }
                         }
                     }
                     "-" -> {
                         if (rightCv == 0.0) {
-                            return listOf(IAstModification.Remove(assignment, assignment.definingScope))
+                            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)
@@ -411,18 +413,18 @@ internal class StatementOptimizer(private val program: Program,
                             }
                         }
                     }
-                    "*" -> if (rightCv == 1.0) return listOf(IAstModification.Remove(assignment, assignment.definingScope))
-                    "/" -> if (rightCv == 1.0) return listOf(IAstModification.Remove(assignment, assignment.definingScope))
-                    "**" -> if (rightCv == 1.0) return listOf(IAstModification.Remove(assignment, assignment.definingScope))
-                    "|" -> if (rightCv == 0.0) return listOf(IAstModification.Remove(assignment, assignment.definingScope))
-                    "^" -> if (rightCv == 0.0) return listOf(IAstModification.Remove(assignment, assignment.definingScope))
+                    "*" -> 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, assignment.definingScope))
+                            return listOf(IAstModification.Remove(assignment, parent as IStatementContainer))
                     }
                     ">>" -> {
                         if (rightCv == 0.0)
-                            return listOf(IAstModification.Remove(assignment, assignment.definingScope))
+                            return listOf(IAstModification.Remove(assignment, parent as IStatementContainer))
                     }
                 }
 
@@ -438,55 +440,35 @@ internal class StatementOptimizer(private val program: Program,
             val returnDt = subr.returntypes.single()
             if (returnDt in IntegerDatatypes) {
                 // first assign to intermediary variable, then return that
-                subsThatNeedReturnVariable.add(Triple(subr, returnDt, returnStmt.position))
-                val returnValueIntermediary1 = IdentifierReference(listOf(retvarName), returnStmt.position)
-                val returnValueIntermediary2 = IdentifierReference(listOf(retvarName), returnStmt.position)
-                val tgt = AssignTarget(returnValueIntermediary1, null, null, returnStmt.position)
-                val assign = Assignment(tgt, value, returnStmt.position)
-                val returnReplacement = Return(returnValueIntermediary2, returnStmt.position)
+                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 INameScope),
+                    IAstModification.InsertBefore(returnStmt, assign, parent as IStatementContainer),
                     IAstModification.ReplaceNode(returnStmt, returnReplacement, parent)
                 )
             }
             return null
         }
 
-        when(returnStmt.value) {
-            is PrefixExpression -> {
-                val mod = returnViaIntermediaryVar(returnStmt.value!!)
+        // TODO decision when to use intermediary variable to calculate returnvalue seems a bit arbitrary...
+        val returnvalue = returnStmt.value
+        if (returnvalue!=null) {
+            if (returnvalue is BinaryExpression || (returnvalue is TypecastExpression && !returnvalue.expression.isSimple)) {
+                val mod = returnViaIntermediaryVar(returnvalue)
                 if(mod!=null)
                     return mod
             }
-            is BinaryExpression -> {
-                val mod = returnViaIntermediaryVar(returnStmt.value!!)
-                if(mod!=null)
-                    return mod
-            }
-            else -> {}
         }
 
-        return super.after(returnStmt, parent)
+        return noModifications
     }
-
-    private fun hasBreak(scope: INameScope): Boolean {
-
-        class Searcher: IAstVisitor
-        {
-            var count=0
-
-            override fun visit(breakStmt: Break) {
-                count++
-            }
-        }
-
-        val s=Searcher()
-        for(stmt in scope.statements) {
-            stmt.accept(s)
-            if(s.count>0)
-                return true
-        }
-        return s.count > 0
-    }
-
 }

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

@@ -3,31 +3,41 @@ plugins {
     id 'application'
     id "org.jetbrains.kotlin.jvm"
     id 'com.github.johnrengelman.shadow' version '7.1.0'
+    id "io.kotest" version "0.3.8"
 }
 
-targetCompatibility = 11
-sourceCompatibility = 11
+java {
+    toolchain {
+        languageVersion = JavaLanguageVersion.of(javaVersion)
+    }
+}
 
+compileKotlin {
+    kotlinOptions {
+        jvmTarget = javaVersion
+    }
+}
 
-repositories {
-    mavenLocal()
-    mavenCentral()
-    maven { url "https://kotlin.bintray.com/kotlinx" }
+compileTestKotlin {
+    kotlinOptions {
+        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 "org.jetbrains.kotlin:kotlin-test-junit5"
-    testImplementation 'org.junit.jupiter:junit-jupiter-api:5.7.2'
-    testImplementation 'org.hamcrest:hamcrest:2.2'
-    testRuntimeOnly 'org.junit.jupiter:junit-jupiter-engine:5.7.2'
+    testImplementation 'io.kotest:kotest-runner-junit5-jvm:4.6.3'
 }
 
 configurations.all {
@@ -43,23 +53,6 @@ configurations {
     }
 }
 
-
-compileKotlin {
-    kotlinOptions {
-        jvmTarget = "11"
-        useIR = true
-        // verbose = true
-        // freeCompilerArgs += "-XXLanguage:+NewInference"
-    }
-}
-
-compileTestKotlin {
-    kotlinOptions {
-        jvmTarget = "11"
-        useIR = true
-    }
-}
-
 sourceSets {
     main {
         java {
@@ -84,11 +77,6 @@ application {
     applicationName = 'p8compile'
 }
 
-artifacts {
-    archives shadowJar
-}
-
-
 shadowJar {
     archiveBaseName = 'prog8compiler'
     archiveVersion = prog8version
@@ -108,3 +96,5 @@ test {
         events "skipped", "failed"
     }
 }
+
+build.finalizedBy installDist, installShadowDist

compiler/compiler.iml

@@ -1,10 +1,5 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <module type="JAVA_MODULE" version="4">
-  <component name="FacetManager">
-    <facet type="Python" name="Python">
-      <configuration sdkName="Python 3.9" />
-    </facet>
-  </component>
   <component name="NewModuleRootManager" inherit-compiler-output="true">
     <exclude-output />
     <content url="file://$MODULE_DIR$">
@@ -13,14 +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="module" module-name="compilerAst" />
-    <orderEntry type="library" name="Python 3.9 interpreter library" level="application" />
-    <orderEntry type="library" name="hamcrest" level="project" />
     <orderEntry type="library" name="jetbrains.kotlinx.cli.jvm" level="project" />
-    <orderEntry type="library" name="junit.jupiter" 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/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

@@ -248,15 +248,25 @@ pop_float_fac1	.proc
 		.pend
 
 copy_float	.proc
-		; -- copies the 5 bytes of the mflt value pointed to by SCRATCH_ZPWORD1,
+		; -- 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  _target+1
-		sty  _target+2
-		ldy  #4
-_loop		lda  (P8ZP_SCRATCH_W1),y
-_target		sta  $ffff,y			; modified
-		dey
-		bpl  _loop
+		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
 
@@ -678,3 +688,54 @@ set_array_float		.proc
 		.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

@@ -12,6 +12,7 @@ floats {
         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 ----
 

compiler/res/prog8lib/c64/graphics.p8

@@ -33,6 +33,9 @@ graphics {
     sub line(uword @zp x1, ubyte @zp y1, uword @zp x2, ubyte @zp y2) {
         ; Bresenham algorithm.
         ; This code special-cases various quadrant loops to allow simple ++ and -- operations.
+        ; TODO implement this as optimized assembly, for instance https://github.com/EgonOlsen71/bresenham/blob/main/src/asm/graphics.asm  ??
+        ;      or from here https://retro64.altervista.org/blog/an-introduction-to-vector-based-graphics-the-commodore-64-rotating-simple-3d-objects/
+
         if y1>y2 {
             ; make sure dy is always positive to have only 4 instead of 8 special cases
             swap(x1, x2)
@@ -160,7 +163,7 @@ graphics {
                 lda  addr+1
                 sta  P8ZP_SCRATCH_W1+1
                 ldy  separate_pixels
-                lda  _filled_right,y
+                lda  hline_filled_right,y
                 eor  #255
                 ldy  #0
                 ora  (P8ZP_SCRATCH_W1),y
@@ -204,18 +207,18 @@ _modified       stx  $ffff      ; modified
 _zero           ldx  P8ZP_SCRATCH_REG
 
                 ldy  separate_pixels
-                beq  _zero2
+                beq  hline_zero2
                 lda  _modified+1
                 sta  P8ZP_SCRATCH_W1
                 lda  _modified+2
                 sta  P8ZP_SCRATCH_W1+1
-                lda  _filled_right,y
+                lda  hline_filled_right,y
                 ldy  #0
                 ora  (P8ZP_SCRATCH_W1),y
                 sta  (P8ZP_SCRATCH_W1),y
-                jmp  _zero2
-_filled_right   .byte  0, %10000000, %11000000, %11100000, %11110000, %11111000, %11111100, %11111110
-_zero2
+                jmp  hline_zero2
+hline_filled_right   .byte  0, %10000000, %11000000, %11100000, %11110000, %11111000, %11111100, %11111110
+hline_zero2
             }}
         }
     }

compiler/res/prog8lib/c64/syslib.p8

@@ -15,7 +15,9 @@ c64 {
 
         &ubyte  COLOR           = $0286     ; cursor color
         &ubyte  HIBASE          = $0288     ; screen base address / 256 (hi-byte of screen memory address)
-        &uword  CINV            = $0314     ; IRQ vector
+        &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
@@ -472,7 +474,7 @@ _setup_raster_irq
 sys {
     ; ------- lowlevel system routines --------
 
-    const ubyte target = 64         ;  compilation target specifier.  64 = C64,  16 = CommanderX16.
+    const ubyte target = 64         ;  compilation target specifier.  64 = C64, 128 = C128, 16 = CommanderX16.
 
 
     asmsub  reset_system()  {
@@ -597,62 +599,34 @@ _longcopy
         }}
     }
 
-
-    inline asmsub rsave() {
-        ; save cpu status flag and all registers A, X, Y.
-        ; see http://6502.org/tutorials/register_preservation.html
-        %asm {{
-            php
-            sta  P8ZP_SCRATCH_REG
-            pha
-            txa
-            pha
-            tya
-            pha
-            lda  P8ZP_SCRATCH_REG
-        }}
-    }
-
-    inline asmsub rrestore() {
-        ; restore all registers and cpu status flag
-        %asm {{
-            pla
-            tay
-            pla
-            tax
-            pla
-            plp
-        }}
-    }
-
     inline asmsub read_flags() -> ubyte @A {
         %asm {{
-            php
-            pla
+        php
+        pla
         }}
     }
 
     inline asmsub clear_carry() {
         %asm {{
-            clc
+        clc
         }}
     }
 
     inline asmsub set_carry() {
         %asm {{
-            sec
+        sec
         }}
     }
 
     inline asmsub clear_irqd() {
         %asm {{
-            cli
+        cli
         }}
     }
 
     inline asmsub set_irqd() {
         %asm {{
-            sei
+        sei
         }}
     }
 
@@ -699,6 +673,23 @@ cx16 {
     &uword r14 = $cf1c
     &uword r15 = $cf1e
 
+    &word r0s  = $cf00
+    &word r1s  = $cf02
+    &word r2s  = $cf04
+    &word r3s  = $cf06
+    &word r4s  = $cf08
+    &word r5s  = $cf0a
+    &word r6s  = $cf0c
+    &word r7s  = $cf0e
+    &word r8s  = $cf10
+    &word r9s  = $cf12
+    &word r10s = $cf14
+    &word r11s = $cf16
+    &word r12s = $cf18
+    &word r13s = $cf1a
+    &word r14s = $cf1c
+    &word r15s = $cf1e
+
     &ubyte r0L  = $cf00
     &ubyte r1L  = $cf02
     &ubyte r2L  = $cf04
@@ -732,4 +723,38 @@ cx16 {
     &ubyte r13H = $cf1b
     &ubyte r14H = $cf1d
     &ubyte r15H = $cf1f
+
+    &byte r0sL  = $cf00
+    &byte r1sL  = $cf02
+    &byte r2sL  = $cf04
+    &byte r3sL  = $cf06
+    &byte r4sL  = $cf08
+    &byte r5sL  = $cf0a
+    &byte r6sL  = $cf0c
+    &byte r7sL  = $cf0e
+    &byte r8sL  = $cf10
+    &byte r9sL  = $cf12
+    &byte r10sL = $cf14
+    &byte r11sL = $cf16
+    &byte r12sL = $cf18
+    &byte r13sL = $cf1a
+    &byte r14sL = $cf1c
+    &byte r15sL = $cf1e
+
+    &byte r0sH  = $cf01
+    &byte r1sH  = $cf03
+    &byte r2sH  = $cf05
+    &byte r3sH  = $cf07
+    &byte r4sH  = $cf09
+    &byte r5sH  = $cf0b
+    &byte r6sH  = $cf0d
+    &byte r7sH  = $cf0f
+    &byte r8sH  = $cf11
+    &byte r9sH  = $cf13
+    &byte r10sH = $cf15
+    &byte r11sH = $cf17
+    &byte r12sH = $cf19
+    &byte r13sH = $cf1b
+    &byte r14sH = $cf1d
+    &byte r15sH = $cf1f
 }

compiler/res/prog8lib/conv.p8

@@ -12,14 +12,14 @@ conv {
 asmsub  str_ub0  (ubyte value @ A) clobbers(A,Y)  {
 	; ---- convert the ubyte in A in decimal string form, with left padding 0s (3 positions total)
 	%asm {{
-            phx
+            stx  P8ZP_SCRATCH_REG
             jsr  conv.ubyte2decimal
             sty  string_out
             sta  string_out+1
             stx  string_out+2
             lda  #0
             sta  string_out+3
-            plx
+            ldx  P8ZP_SCRATCH_REG
             rts
 	}}
 }
@@ -27,7 +27,7 @@ asmsub  str_ub0  (ubyte value @ A) clobbers(A,Y)  {
 asmsub  str_ub  (ubyte value @ A) clobbers(A,Y)  {
 	; ---- convert the ubyte in A in decimal string form, without left padding 0s
 	%asm {{
-		phx
+		stx  P8ZP_SCRATCH_REG
 		ldy  #0
 		sty  P8ZP_SCRATCH_B1
 		jsr  conv.ubyte2decimal
@@ -53,7 +53,7 @@ _output_byte_digits
                 iny
                 lda  #0
                 sta  string_out,y
-                plx
+                ldx  P8ZP_SCRATCH_REG
                 rts
 	}}
 }
@@ -61,7 +61,7 @@ _output_byte_digits
 asmsub  str_b  (byte value @ A) clobbers(A,Y)  {
 	; ---- convert the byte in A in decimal string form, without left padding 0s
 	%asm {{
-            phx
+            stx  P8ZP_SCRATCH_REG
             ldy  #0
             sty  P8ZP_SCRATCH_B1
             cmp  #0
@@ -149,7 +149,7 @@ asmsub  str_uwhex  (uword value @ AY) clobbers(A,Y)  {
 asmsub  str_uw0  (uword value @ AY) clobbers(A,Y)  {
 	; ---- convert the uword in A/Y in decimal string form, with left padding 0s (5 positions total)
 	%asm {{
-	    phx
+	    stx  P8ZP_SCRATCH_REG
 	    jsr  conv.uword2decimal
 	    ldy  #0
 -           lda  conv.uword2decimal.decTenThousands,y
@@ -157,7 +157,7 @@ asmsub  str_uw0  (uword value @ AY) clobbers(A,Y)  {
             beq  +
             iny
             bne  -
-+           plx
++           ldx  P8ZP_SCRATCH_REG
 	    rts
 	}}
 }
@@ -165,7 +165,7 @@ asmsub  str_uw0  (uword value @ AY) clobbers(A,Y)  {
 asmsub  str_uw  (uword value @ AY) clobbers(A,Y)  {
 	; ---- convert the uword in A/Y in decimal string form, without left padding 0s
 	%asm {{
-	    phx
+	    stx  P8ZP_SCRATCH_REG
 	    jsr  conv.uword2decimal
 	    ldx  #0
 _output_digits
@@ -183,7 +183,7 @@ _gotdigit   sta  string_out,x
             bne  _gotdigit
 _end        lda  #0
             sta  string_out,x
-            plx
+            ldx  P8ZP_SCRATCH_REG
             rts
 
 _allzero    lda  #'0'
@@ -198,7 +198,7 @@ asmsub  str_w  (word value @ AY) clobbers(A,Y)  {
 	%asm {{
 	    cpy  #0
 	    bpl  str_uw
-	    phx
+	    stx  P8ZP_SCRATCH_REG
 	    pha
 	    lda  #'-'
 	    sta  string_out
@@ -516,7 +516,7 @@ asmsub  uword2decimal  (uword value @AY) -> ubyte @Y, ubyte @A, ubyte @X  {
 
 ;Convert 16 bit Hex to Decimal (0-65535) Rev 2
 ;By Omegamatrix    Further optimizations by tepples
-; routine from http://forums.nesdev.com/viewtopic.php?f=2&t=11341&start=15
+; routine from https://forums.nesdev.org/viewtopic.php?f=2&t=11341&start=15
 
 ;HexToDec99
 ; start in A

compiler/res/prog8lib/cx16/cx16diskio.p8

@@ -0,0 +1,37 @@
+; Cx16 specific disk drive I/O routines.
+;
+; Written by Irmen de Jong (irmen@razorvine.net) - license: GNU GPL 3.0
+
+%import diskio
+
+cx16diskio {
+
+    ; Use kernal LOAD routine to load the given program file in memory.
+    ; This is similar to Basic's  LOAD "filename",drive  /  LOAD "filename",drive,1
+    ; If you don't give an address_override, the location in memory is taken from the 2-byte file header.
+    ; If you specify a custom address_override, the first 2 bytes in the file are ignored
+    ; and the rest is loaded at the given location in memory.
+    ; Returns the end load address+1 if successful or 0 if a load error occurred.
+    ; You can use the load_size() function to calcuate the size of the file that was loaded.
+    sub load(ubyte drivenumber, uword filenameptr, ubyte bank, uword address_override) -> uword {
+        cx16.rambank(bank)
+        return diskio.load(drivenumber, filenameptr, address_override)
+    }
+
+    ; Use kernal LOAD routine to load the given file in memory.
+    ; INCLUDING the first 2 bytes in the file: no program header is assumed in the file.
+    ; This is different from Basic's LOAD instruction which always skips the first two bytes.
+    ; The load address is mandatory. Returns the number of bytes loaded.
+    ; Returns the end load address+1 if successful or 0 if a load error occurred.
+    ; You can use the load_size() function to calcuate the size of the file that was loaded.
+    sub load_raw(ubyte drivenumber, uword filenameptr, ubyte bank, uword address) -> uword {
+        cx16.rambank(bank)
+        return diskio.load_raw(drivenumber, filenameptr, address)
+    }
+
+    ; For use directly after a load or load_raw call (don't mess with the ram bank yet):
+    ; Calculates the number of bytes loaded (files > 64Kb ar truncated to 16 bits)
+    sub load_size(ubyte startbank, uword startaddress, uword endaddress) -> uword {
+        return $2000 * (cx16.getrambank() - startbank) + endaddress - startaddress
+    }
+}

compiler/res/prog8lib/cx16/floats.p8

@@ -10,10 +10,11 @@ floats {
 	; ---- this block contains C-64 compatible floating point related functions ----
 	;      the addresses are from cx16 V39 emulator and roms! they won't work on older versions.
 
-
         const float  PI     = 3.141592653589793
         const float  TWOPI  = 6.283185307179586
 
+        float  tempvar_swap_float     ; used for some swap() operations
+
 
 ; ---- ROM float functions ----
 

compiler/res/prog8lib/cx16/gfx2.p8

@@ -775,6 +775,7 @@ _done
         ; -- Write some text at the given pixel position. The text string must be in screencode encoding (not petscii!).
         ;    You must also have called text_charset() first to select and prepare the character set to use.
         ;    NOTE: in monochrome (1bpp) screen modes, x position is currently constrained to multiples of 8 !  TODO allow per-pixel horizontal positioning
+        ; TODO draw whole horizontal spans using vera auto increment if possible, instead of per-character columns
         uword chardataptr
         when active_mode {
             1, 5 -> {
@@ -808,11 +809,8 @@ _done
                         sta  cx16.VERA_ADDR_L
                         bcc  +
                         inc  cx16.VERA_ADDR_M
-+                       lda  x
-                        clc
-                        adc  #1
-                        sta  x
-                        bcc  +
++                       inc  x
+                        bne  +
                         inc  x+1
 +                       dey
                         bne  -
@@ -826,7 +824,6 @@ _done
                     chardataptr = charset_addr + (@(sctextptr) as uword)*8
                     cx16.vaddr(charset_bank, chardataptr, 1, 1)
                     repeat 8 {
-                        ; TODO rewrite this inner loop fully in assembly
                         position(x,y)
                         y++
                         %asm {{
@@ -855,7 +852,9 @@ _done
                 while @(sctextptr) {
                     chardataptr = charset_addr + (@(sctextptr) as uword)*8
                     repeat 8 {
-                        ; TODO rewrite this inner loop fully in assembly
+                        ; TODO rewrite this inner loop partly in assembly
+                        ;      requires expanding the charbits to 2-bits per pixel (based on color)
+                        ;      also it's way more efficient to draw whole horizontal spans instead of per-character
                         ubyte charbits = cx16.vpeek(charset_bank, chardataptr)
                         repeat 8 {
                             charbits <<= 1

compiler/res/prog8lib/cx16/syslib.p8

@@ -11,7 +11,7 @@ c64 {
 
 ; STROUT --> use txt.print
 ; CLEARSCR -> use txt.clear_screen
-; HOMECRSR -> use txt.plot
+; HOMECRSR -> use txt.home or txt.plot
 
 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)
@@ -90,12 +90,14 @@ cx16 {
 
 ; irq and hardware vectors:
     &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     ; 65c02 nmi vector, determined by the kernal if banked in
     &uword  RESET_VEC       = $FFFC     ; 65c02 reset vector, determined by the kernal if banked in
     &uword  IRQ_VEC         = $FFFE     ; 65c02 interrupt vector, determined by the kernal if banked in
 
 
-; the sixteen virtual 16-bit registers
+; the sixteen virtual 16-bit registers in both normal unsigned mode and signed mode (s)
     &uword r0  = $0002
     &uword r1  = $0004
     &uword r2  = $0006
@@ -113,6 +115,23 @@ cx16 {
     &uword r14 = $001e
     &uword r15 = $0020
 
+    &word r0s  = $0002
+    &word r1s  = $0004
+    &word r2s  = $0006
+    &word r3s  = $0008
+    &word r4s  = $000a
+    &word r5s  = $000c
+    &word r6s  = $000e
+    &word r7s  = $0010
+    &word r8s  = $0012
+    &word r9s  = $0014
+    &word r10s = $0016
+    &word r11s = $0018
+    &word r12s = $001a
+    &word r13s = $001c
+    &word r14s = $001e
+    &word r15s = $0020
+
     &ubyte r0L  = $0002
     &ubyte r1L  = $0004
     &ubyte r2L  = $0006
@@ -147,6 +166,39 @@ cx16 {
     &ubyte r14H = $001f
     &ubyte r15H = $0021
 
+    &byte r0sL  = $0002
+    &byte r1sL  = $0004
+    &byte r2sL  = $0006
+    &byte r3sL  = $0008
+    &byte r4sL  = $000a
+    &byte r5sL  = $000c
+    &byte r6sL  = $000e
+    &byte r7sL  = $0010
+    &byte r8sL  = $0012
+    &byte r9sL  = $0014
+    &byte r10sL = $0016
+    &byte r11sL = $0018
+    &byte r12sL = $001a
+    &byte r13sL = $001c
+    &byte r14sL = $001e
+    &byte r15sL = $0020
+
+    &byte r0sH  = $0003
+    &byte r1sH  = $0005
+    &byte r2sH  = $0007
+    &byte r3sH  = $0009
+    &byte r4sH  = $000b
+    &byte r5sH  = $000d
+    &byte r6sH  = $000f
+    &byte r7sH  = $0011
+    &byte r8sH  = $0013
+    &byte r9sH  = $0015
+    &byte r10sH = $0017
+    &byte r11sH = $0019
+    &byte r12sH = $001b
+    &byte r13sH = $001d
+    &byte r14sH = $001f
+    &byte r15sH = $0021
 
 ; VERA registers
 
@@ -255,14 +307,27 @@ romsub $ff7d = primm()
 romsub $ff44 = macptr()  clobbers(A,X,Y)
 romsub $ff47 = enter_basic(ubyte cold_or_warm @Pc)  clobbers(A,X,Y)
 romsub $ff68 = mouse_config(ubyte shape @A, ubyte scale @X)  clobbers (A, X, Y)
-romsub $ff6b = mouse_get(ubyte zpdataptr @X)  clobbers(A)
+romsub $ff6b = mouse_get(ubyte zpdataptr @X) -> ubyte @A
 romsub $ff71 = mouse_scan()  clobbers(A, X, Y)
 romsub $ff53 = joystick_scan()  clobbers(A, X, Y)
 romsub $ff56 = joystick_get(ubyte joynr @A) -> ubyte @A, ubyte @X, ubyte @Y
 romsub $ff4d = clock_set_date_time(uword yearmonth @R0, uword dayhours @R1, uword minsecs @R2, ubyte jiffies @R3)  clobbers(A, X, Y)
 romsub $ff50 = clock_get_date_time()  clobbers(A, X, Y)  -> uword @R0, uword @R1, uword @R2, ubyte @R3   ; result registers see clock_set_date_time()
 
-; TODO specify the correct clobbers for alle these functions below, we now assume all 3 regs are clobbered
+asmsub mouse_pos() -> ubyte @A {
+    ; -- short wrapper around mouse_get() kernal routine:
+    ; -- gets the position of the mouse cursor in cx16.r0 and cx16.r1 (x/y coordinate), returns mouse button status.
+    %asm {{
+        phx
+        ldx  #cx16.r0
+        jsr  cx16.mouse_get
+        plx
+        rts
+    }}
+}
+
+
+; It's not documented what registers are clobbered, so we assume the worst for all following kernal routines...:
 
 ; high level graphics & fonts
 romsub $ff20 = GRAPH_init(uword vectors @R0)  clobbers(A,X,Y)
@@ -317,20 +382,34 @@ romsub $fecc = monitor()  clobbers(A,X,Y)
 
 ; ---- utilities -----
 
-inline asmsub rombank(ubyte rombank @A) {
+inline asmsub rombank(ubyte bank @A) {
     ; -- set the rom banks
     %asm {{
         sta  $01            ; rom bank register (v39+, used to be cx16.d1prb $9f60 in v38)
     }}
 }
 
-inline asmsub rambank(ubyte rambank @A) {
+inline asmsub rambank(ubyte bank @A) {
     ; -- set the ram bank
     %asm {{
         sta  $00            ; ram bank register (v39+, used to be cx16.d1pra $9f61 in v38)
     }}
 }
 
+inline asmsub getrombank() -> ubyte @A {
+    ; -- get the current rom bank
+    %asm {{
+        lda  $01            ; rom bank register (v39+, used to be cx16.d1prb $9f60 in v38)
+    }}
+}
+
+inline asmsub getrambank() -> ubyte @A {
+    ; -- get the current ram bank
+    %asm {{
+        lda  $00            ; ram bank register (v39+, used to be cx16.d1pra $9f61 in v38)
+    }}
+}
+
 asmsub numbanks() -> ubyte @A {
     ; -- uses MEMTOP's cx16 extension to query the number of available RAM banks. (each is 8 Kb)
     %asm {{
@@ -744,7 +823,7 @@ asmsub  set_rasterline(uword line @AY) {
 sys {
     ; ------- lowlevel system routines --------
 
-    const ubyte target = 16         ;  compilation target specifier.  64 = C64,  16 = CommanderX16.
+    const ubyte target = 16         ;  compilation target specifier.  64 = C64,  128 = C128,  16 = CommanderX16.
 
 
     asmsub reset_system() {
@@ -809,27 +888,6 @@ sys {
         }}
     }
 
-    inline asmsub rsave() {
-        ; save cpu status flag and all registers A, X, Y.
-        ; see http://6502.org/tutorials/register_preservation.html
-        %asm {{
-            php
-            pha
-            phy
-            phx
-        }}
-    }
-
-    inline asmsub rrestore() {
-        ; restore all registers and cpu status flag
-        %asm {{
-            plx
-            ply
-            pla
-            plp
-        }}
-    }
-
     inline asmsub read_flags() -> ubyte @A {
         %asm {{
             php
@@ -839,25 +897,25 @@ sys {
 
     inline asmsub clear_carry() {
         %asm {{
-            clc
+        clc
         }}
     }
 
     inline asmsub set_carry() {
         %asm {{
-            sec
+        sec
         }}
     }
 
     inline asmsub clear_irqd() {
         %asm {{
-            cli
+        cli
         }}
     }
 
     inline asmsub set_irqd() {
         %asm {{
-            sei
+        sei
         }}
     }
 

compiler/res/prog8lib/cx16/textio.p8

@@ -169,13 +169,26 @@ sub color2 (ubyte txtcol, ubyte bgcol) {
 }
 
 sub lowercase() {
-    cx16.screen_set_charset(3, 0)  ; lowercase charset
+    c64.CHROUT($0e)
+    ; this is not 100% compatible: cx16.screen_set_charset(3, 0)  ; lowercase petscii charset
 }
 
 sub uppercase() {
-    cx16.screen_set_charset(2, 0)  ; uppercase charset
+    c64.CHROUT($8e)
+    ; this is not 100% compatible: cx16.screen_set_charset(2, 0)  ; uppercase petscii charset
 }
 
+sub iso() {
+    c64.CHROUT($0f)
+    ; This doesn't enable it completely: cx16.screen_set_charset(1, 0)  ; iso charset
+}
+
+sub iso_off() {
+    ; -- you have to call this first when switching back from iso charset to regular charset.
+    c64.CHROUT($8f)
+}
+
+
 asmsub  scroll_left() 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
@@ -565,9 +578,8 @@ asmsub  print_w  (word value @ AY) clobbers(A,Y)  {
 		tay
 		pla
 		eor  #255
-		clc
-		adc  #1
-		bcc  +
+		ina
+		bne +
 		iny
 +		bra  print_uw
 	}}

compiler/res/prog8lib/cx16logo.p8

@@ -20,12 +20,12 @@ cx16logo {
     }
 
     str[] logo_lines = [
-            "\uf10d\uf11a\uf139\uf11b     \uf11a\uf13a\uf11b\n",
-            "\uf10b\uf11a▎\uf139\uf11b   \uf11a\uf13a\uf130\uf11b\n",
-            "\uf10f\uf11a▌ \uf139\uf11b \uf11a\uf13a \uf11b▌\n",
-            "\uf102 \uf132\uf11a▖\uf11b \uf11a▗\uf11b\uf132\n",
-            "\uf10e ▂\uf11a▘\uf11b \uf11a▝\uf11b▂\n",
-            "\uf104 \uf11a \uf11b\uf13a\uf11b \uf139\uf11a \uf11b\n",
+            "\uf10d\uf11a\uf139\uf11b     \uf11a\uf13a\uf11b",
+            "\uf10b\uf11a▎\uf139\uf11b   \uf11a\uf13a\uf130\uf11b",
+            "\uf10f\uf11a▌ \uf139\uf11b \uf11a\uf13a \uf11b▌",
+            "\uf102 \uf132\uf11a▖\uf11b \uf11a▗\uf11b\uf132",
+            "\uf10e ▂\uf11a▘\uf11b \uf11a▝\uf11b▂",
+            "\uf104 \uf11a \uf11b\uf13a\uf11b \uf139\uf11a \uf11b",
             "\uf101\uf130\uf13a   \uf139▎\uf100"
         ]
 }

compiler/res/prog8lib/diskio.p8

@@ -242,18 +242,18 @@ close_end:
         void c64.CHKIN(11)        ; use #11 as input channel again
         %asm {{
             lda  bufferpointer
-            sta  _in_buffer+1
+            sta  m_in_buffer+1
             lda  bufferpointer+1
-            sta  _in_buffer+2
+            sta  m_in_buffer+2
         }}
         repeat num_bytes {
             %asm {{
                 jsr  c64.CHRIN
                 sta  cx16.r5
-_in_buffer      sta  $ffff
-                inc  _in_buffer+1
+m_in_buffer     sta  $ffff
+                inc  m_in_buffer+1
                 bne  +
-                inc  _in_buffer+2
+                inc  m_in_buffer+2
 +               inc  list_blocks
                 bne  +
                 inc  list_blocks+1
@@ -433,10 +433,20 @@ io_error:
         return first_byte
     }
 
+    ; Use kernal LOAD routine to load the given program file in memory.
+    ; This is similar to Basic's  LOAD "filename",drive  /  LOAD "filename",drive,1
+    ; If you don't give an address_override, the location in memory is taken from the 2-byte file header.
+    ; If you specify a custom address_override, the first 2 bytes in the file are ignored
+    ; and the rest is loaded at the given location in memory.
+    ; Returns the end load address+1 if successful or 0 if a load error occurred.
+    ; NOTE: when the load is larger than 64Kb and/or spans multiple RAM banks
+    ;       (which is possible on the Commander X16), the returned size is not correct,
+    ;       because it doesn't take the number of ram banks into account.
+    ;       Consider using cx16diskio.load() instead.
     sub load(ubyte drivenumber, uword filenameptr, uword address_override) -> uword {
         c64.SETNAM(string.length(filenameptr), filenameptr)
         ubyte secondary = 1
-        uword end_of_load = 0
+        cx16.r1 = 0
         if address_override
             secondary = 0
         c64.SETLFS(1, drivenumber, secondary)
@@ -447,22 +457,35 @@ io_error:
             ldy  address_override+1
             jsr  c64.LOAD
             bcs  +
-            stx  end_of_load
-            sty  end_of_load+1
+            stx  cx16.r1
+            sty  cx16.r1+1
 +           ldx  P8ZP_SCRATCH_REG
         }}
 
         c64.CLRCHN()
         c64.CLOSE(1)
-
-        if end_of_load
-            return end_of_load - address_override
-
-        return 0
+        return cx16.r1
     }
 
-
-    str filename = "0:??????????????????????????????????????"
+    ; Use kernal LOAD routine to load the given file in memory.
+    ; INCLUDING the first 2 bytes in the file: no program header is assumed in the file.
+    ; This is different from Basic's LOAD instruction which always skips the first two bytes.
+    ; The load address is mandatory.
+    ; Returns the end load address+1 if successful or 0 if a load error occurred.
+    ; NOTE: when the load is larger than 64Kb and/or spans multiple RAM banks
+    ;       (which is possible on the Commander X16), the returned size is not correct,
+    ;       because it doesn't take the number of ram banks into account.
+    ;       Consider using cx16diskio.load_raw() instead.
+    sub load_raw(ubyte drivenumber, uword filenameptr, uword address) -> uword {
+        if not f_open(drivenumber, filenameptr)
+            return 0
+        cx16.r1 = f_read(address, 2)
+        f_close()
+        if cx16.r1!=2
+            return 0
+        address += 2
+        return load(drivenumber, filenameptr, address)
+    }
 
     sub delete(ubyte drivenumber, uword filenameptr) {
         ; -- delete a file on the drive
@@ -489,4 +512,6 @@ io_error:
         c64.CLRCHN()
         c64.CLOSE(1)
     }
+
+    str filename = "0:??????????????????????????????????????"
 }

compiler/res/prog8lib/prog8_funcs.asm

@@ -91,6 +91,13 @@ func_sin8_into_A	.proc
 _sinecos8	.char  trunc(127.0 * sin(range(256+64) * rad(360.0/256.0)))
 		.pend
 
+func_sinr8_into_A	.proc
+		tay
+		lda  _sinecosR8,y
+		rts
+_sinecosR8	.char  trunc(127.0 * sin(range(180+45) * rad(360.0/180.0)))
+		.pend
+
 func_sin8u_into_A	.proc
 		tay
 		lda  _sinecos8u,y
@@ -98,6 +105,13 @@ func_sin8u_into_A	.proc
 _sinecos8u	.byte  trunc(128.0 + 127.5 * sin(range(256+64) * rad(360.0/256.0)))
 		.pend
 
+func_sinr8u_into_A	.proc
+		tay
+		lda  _sinecosR8u,y
+		rts
+_sinecosR8u	.byte  trunc(128.0 + 127.5 * sin(range(180+45) * rad(360.0/180.0)))
+		.pend
+
 func_sin8_stack	.proc
 		tay
 		lda  func_sin8_into_A._sinecos8,y
@@ -106,6 +120,14 @@ func_sin8_stack	.proc
 		rts
 		.pend
 
+func_sinr8_stack	.proc
+		tay
+		lda  func_sinr8_into_A._sinecosR8,y
+		sta  P8ESTACK_LO,x
+		dex
+		rts
+		.pend
+
 func_sin8u_stack	.proc
 		tay
 		lda  func_sin8u_into_A._sinecos8u,y
@@ -114,18 +136,38 @@ func_sin8u_stack	.proc
 		rts
 		.pend
 
+func_sinr8u_stack	.proc
+		tay
+		lda  func_sinr8u_into_A._sinecosR8u,y
+		sta  P8ESTACK_LO,x
+		dex
+		rts
+		.pend
+
 func_cos8_into_A	.proc
 		tay
 		lda  func_sin8_into_A._sinecos8+64,y
 		rts
 		.pend
 
+func_cosr8_into_A	.proc
+		tay
+		lda  func_sinr8_into_A._sinecosR8+45,y
+		rts
+		.pend
+
 func_cos8u_into_A	.proc
 		tay
 		lda  func_sin8u_into_A._sinecos8u+64,y
 		rts
 		.pend
 
+func_cosr8u_into_A	.proc
+		tay
+		lda  func_sinr8u_into_A._sinecosR8u+45,y
+		rts
+		.pend
+
 func_cos8_stack	.proc
 		tay
 		lda  func_sin8_into_A._sinecos8+64,y
@@ -134,6 +176,14 @@ func_cos8_stack	.proc
 		rts
 		.pend
 
+func_cosr8_stack	.proc
+		tay
+		lda  func_sinr8_into_A._sinecosR8+45,y
+		sta  P8ESTACK_LO,x
+		dex
+		rts
+		.pend
+
 func_cos8u_stack	.proc
 		tay
 		lda  func_sin8u_into_A._sinecos8u+64,y
@@ -142,6 +192,14 @@ func_cos8u_stack	.proc
 		rts
 		.pend
 
+func_cosr8u_stack	.proc
+		tay
+		lda  func_sinr8u_into_A._sinecosR8u+45,y
+		sta  P8ESTACK_LO,x
+		dex
+		rts
+		.pend
+
 func_sin16_into_AY	.proc
 		tay
 		lda  _sinecos8lo,y
@@ -155,6 +213,19 @@ _sinecos8lo     .byte  <_
 _sinecos8hi     .byte  >_
 		.pend
 
+func_sinr16_into_AY	.proc
+		tay
+		lda  _sinecosR8lo,y
+		pha
+		lda  _sinecosR8hi,y
+		tay
+		pla
+		rts
+_  :=  trunc(32767.0 * sin(range(180+45) * rad(360.0/180.0)))
+_sinecosR8lo     .byte  <_
+_sinecosR8hi     .byte  >_
+		.pend
+
 func_sin16u_into_AY	.proc
 		tay
 		lda  _sinecos8ulo,y
@@ -168,6 +239,18 @@ _sinecos8ulo     .byte  <_
 _sinecos8uhi     .byte  >_
 		.pend
 
+func_sinr16u_into_AY	.proc
+		tay
+		lda  _sinecosR8ulo,y
+		pha
+		lda  _sinecosR8uhi,y
+		tay
+		pla
+		rts
+_  :=  trunc(32768.0 + 32767.5 * sin(range(180+45) * rad(360.0/180.0)))
+_sinecosR8ulo     .byte  <_
+_sinecosR8uhi     .byte  >_
+		.pend
 
 func_sin16_stack	.proc
 		tay
@@ -179,6 +262,16 @@ func_sin16_stack	.proc
 		rts
 		.pend
 
+func_sinr16_stack	.proc
+		tay
+		lda  func_sinr16_into_AY._sinecosR8lo,y
+		sta  P8ESTACK_LO,x
+		lda  func_sinr16_into_AY._sinecosR8hi,y
+		sta  P8ESTACK_HI,x
+		dex
+		rts
+		.pend
+
 func_sin16u_stack	.proc
 		tay
 		lda  func_sin16u_into_AY._sinecos8ulo,y
@@ -189,6 +282,16 @@ func_sin16u_stack	.proc
 		rts
 		.pend
 
+func_sinr16u_stack	.proc
+		tay
+		lda  func_sinr16u_into_AY._sinecosR8ulo,y
+		sta  P8ESTACK_LO,x
+		lda  func_sinr16u_into_AY._sinecosR8uhi,y
+		sta  P8ESTACK_HI,x
+		dex
+		rts
+		.pend
+
 func_cos16_into_AY	.proc
 		tay
 		lda  func_sin16_into_AY._sinecos8lo+64,y
@@ -199,6 +302,16 @@ func_cos16_into_AY	.proc
 		rts
 		.pend
 
+func_cosr16_into_AY	.proc
+		tay
+		lda  func_sinr16_into_AY._sinecosR8lo+45,y
+		pha
+		lda  func_sinr16_into_AY._sinecosR8hi+45,y
+		tay
+		pla
+		rts
+		.pend
+
 func_cos16u_into_AY	.proc
 		tay
 		lda  func_sin16u_into_AY._sinecos8ulo+64,y
@@ -209,6 +322,16 @@ func_cos16u_into_AY	.proc
 		rts
 		.pend
 
+func_cosr16u_into_AY	.proc
+		tay
+		lda  func_sinr16u_into_AY._sinecosR8ulo+45,y
+		pha
+		lda  func_sinr16u_into_AY._sinecosR8uhi+45,y
+		tay
+		pla
+		rts
+		.pend
+
 func_cos16_stack	.proc
 		tay
 		lda  func_sin16_into_AY._sinecos8lo+64,y
@@ -219,6 +342,16 @@ func_cos16_stack	.proc
 		rts
 		.pend
 
+func_cosr16_stack	.proc
+		tay
+		lda  func_sinr16_into_AY._sinecosR8lo+45,y
+		sta  P8ESTACK_LO,x
+		lda  func_sinr16_into_AY._sinecosR8hi+45,y
+		sta  P8ESTACK_HI,x
+		dex
+		rts
+		.pend
+
 func_cos16u_stack	.proc
 		tay
 		lda  func_sin16u_into_AY._sinecos8ulo+64,y
@@ -229,6 +362,16 @@ func_cos16u_stack	.proc
 		rts
 		.pend
 
+func_cosr16u_stack	.proc
+		tay
+		lda  func_sinr16u_into_AY._sinecosR8ulo+45,y
+		sta  P8ESTACK_LO,x
+		lda  func_sinr16u_into_AY._sinecosR8uhi+45,y
+		sta  P8ESTACK_HI,x
+		dex
+		rts
+		.pend
+
 abs_b_stack	.proc
 	; -- push abs(A) on stack (as byte)
 		jsr  abs_b_into_A

compiler/res/prog8lib/prog8_lib.asm

@@ -4,6 +4,8 @@
 ; Written by Irmen de Jong (irmen@razorvine.net) - license: GNU GPL 3.0
 
 
+orig_stackpointer	.byte  0	; stores the Stack pointer register at program start
+
 read_byte_from_address_on_stack	.proc
 	; -- read the byte from the memory address on the top of the stack, return in A (stack remains unchanged)
 		lda  P8ESTACK_LO+1,x
@@ -683,8 +685,106 @@ shiftright_b	.proc
 		.pend
 
 
-orig_stackpointer	.byte  0	; stores the Stack pointer register at program start
+equalzero_b	.proc
+		lda  P8ESTACK_LO+1,x
+		beq  _true
+		bne  _false
+_true		lda  #1
+		sta  P8ESTACK_LO+1,x
+		rts
+_false		lda  #0
+		sta  P8ESTACK_LO+1,x
+		rts
+		.pend
 
+equalzero_w	.proc
+		lda  P8ESTACK_LO+1,x
+		ora  P8ESTACK_HI+1,x
+		beq  equalzero_b._true
+		bne  equalzero_b._false
+		.pend
+
+notequalzero_b	.proc
+		lda  P8ESTACK_LO+1,x
+		beq  equalzero_b._false
+		bne  equalzero_b._true
+		.pend
+
+notequalzero_w	.proc
+		lda  P8ESTACK_LO+1,x
+		ora  P8ESTACK_HI+1,x
+		beq  equalzero_b._false
+		bne  equalzero_b._true
+		.pend
+
+lesszero_b	.proc
+		lda  P8ESTACK_LO+1,x
+		bmi  equalzero_b._true
+		jmp  equalzero_b._false
+		.pend
+
+lesszero_w	.proc
+		lda  P8ESTACK_HI+1,x
+		bmi  equalzero_b._true
+		jmp  equalzero_b._false
+		.pend
+
+greaterzero_ub	.proc
+		lda  P8ESTACK_LO+1,x
+		bne  equalzero_b._true
+		beq  equalzero_b._false
+		.pend
+
+greaterzero_sb	.proc
+		lda  P8ESTACK_LO+1,x
+		beq  equalzero_b._false
+		bpl  equalzero_b._true
+		bmi  equalzero_b._false
+		.pend
+
+greaterzero_uw	.proc
+		lda  P8ESTACK_LO+1,x
+		ora  P8ESTACK_HI+1,x
+		bne  equalzero_b._true
+		beq  equalzero_b._false
+		.pend
+
+greaterzero_sw	.proc
+		lda  P8ESTACK_HI+1,x
+		bmi  equalzero_b._false
+		ora  P8ESTACK_LO+1,x
+		beq  equalzero_b._false
+		bne  equalzero_b._true
+		.pend
+
+lessequalzero_sb	.proc
+		lda  P8ESTACK_LO+1,x
+		bmi  equalzero_b._true
+		beq  equalzero_b._true
+		bne  equalzero_b._false
+		.pend
+
+lessequalzero_sw	.proc
+		lda  P8ESTACK_HI+1,x
+		bmi  equalzero_b._true
+		ora  P8ESTACK_LO+1,x
+		beq  equalzero_b._true
+		bne  equalzero_b._false
+		.pend
+
+greaterequalzero_sb	.proc
+		lda  P8ESTACK_LO+1,x
+	    	bpl  equalzero_b._true
+	    	bmi  equalzero_b._false
+		.pend
+
+greaterequalzero_sw	.proc
+		lda  P8ESTACK_HI+1,x
+		bmi  equalzero_b._false
+		ora  P8ESTACK_LO+1,x
+		beq  equalzero_b._true
+		bne  equalzero_b._false
+		.pend
 
 
 memcopy16_up	.proc
@@ -1083,3 +1183,45 @@ strlen          .proc
 		bne  -
 +		rts
 		.pend
+
+
+containment_bytearray	.proc
+	; -- check if a value exists in a byte array.
+	;    parameters: P8ZP_SCRATCH_W1: address of the byte array, A = byte to check, Y = length of array (>=1).
+	;    returns boolean 0/1 in A.
+		dey
+-		cmp  (P8ZP_SCRATCH_W1),y
+		beq  +
+		dey
+		cpy  #255
+		bne  -
+		lda  #0
+		rts
++		lda  #1
+		rts
+		.pend
+
+containment_wordarray	.proc
+	; -- check if a value exists in a word array.
+	;    parameters: P8ZP_SCRATCH_W1: value to check, P8ZP_SCRATCH_W2: address of the word array, Y = length of array (>=1).
+	;    returns boolean 0/1 in A.
+		dey
+		tya
+		asl  a
+		tay
+-		lda  P8ZP_SCRATCH_W1
+		cmp  (P8ZP_SCRATCH_W2),y
+		bne  +
+		lda  P8ZP_SCRATCH_W1+1
+		iny
+		cmp  (P8ZP_SCRATCH_W2),y
+		beq  _found
++		dey
+		dey
+		cpy  #254
+		bne  -
+		lda  #0
+		rts
+_found		lda  #1
+		rts
+		.pend

compiler/res/prog8lib/prog8_lib.p8

@@ -6,10 +6,24 @@ prog8_lib {
 	%asminclude "library:prog8_lib.asm"
 	%asminclude "library:prog8_funcs.asm"
 
-	uword @zp retval_interm_uw      ; to store intermediary expression results for return values (hopefully allocated on ZP to reduce code size)
-	word @zp retval_interm_w        ; to store intermediary expression results for return values (hopefully allocated on ZP to reduce code size)
-	ubyte @zp retval_interm_ub      ; to store intermediary expression results for return values (hopefully allocated on ZP to reduce code size)
-	byte @zp retval_interm_b        ; to store intermediary expression results for return values (hopefully allocated on ZP to reduce code size)
+	; to store intermediary expression results for return values:
+	; NOTE: these variables are used in the StatementReorderer and StatementOptimizer
+	uword @zp retval_interm_uw
+	word @zp retval_interm_w
+	ubyte @zp retval_interm_ub
+	byte @zp retval_interm_b
+	word retval_interm_w2
+	byte retval_interm_b2
+
+        ; prog8 "hooks" to be able to access the temporary scratch variables
+        ; YOU SHOULD NOT USE THESE IN USER CODE - THESE ARE MEANT FOR INTERNAL COMPILER USE
+        ; NOTE: the assembly code generator will match these names and not generate
+        ;       new variables/memdefs for them, rather, they'll point to the scratch variables directly.
+        &ubyte P8ZP_SCRATCH_REG = $ff
+        &byte P8ZP_SCRATCH_B1 = $ff
+        &uword P8ZP_SCRATCH_W1 = $ff
+        &word P8ZP_SCRATCH_W2 = $ff
+
 
 	asmsub pattern_match(str string @AY, str pattern @R0) clobbers(Y) -> ubyte @A {
 		%asm {{

compiler/res/prog8lib/string.p8

@@ -134,7 +134,7 @@ _startloop	dey
         ; Locates the first position of the given character in the string,
         ;  returns the string starting with this character or $0000 if the character is not found.
         %asm {{
-                ; need to copy the the cx16 virtual registers to zeropage to be compatible with C64...
+                ; need to copy the the cx16 virtual registers to zeropage to make this run on C64...
                 sta  P8ZP_SCRATCH_B1
 		lda  cx16.r0
 		ldy  cx16.r0+1

compiler/res/version.txt

@@ -1 +1 @@
-7.1
+7.7.1

compiler/src/prog8/CompilerMain.kt

@@ -2,11 +2,12 @@ package prog8
 
 import kotlinx.cli.*
 import prog8.ast.base.AstException
+import prog8.codegen.target.C128Target
 import prog8.compiler.CompilationResult
+import prog8.compiler.CompilerArguments
 import prog8.compiler.compileProgram
-import prog8.compiler.target.C64Target
-import prog8.compiler.target.Cx16Target
-import prog8.parser.ParsingFailedError
+import prog8.codegen.target.C64Target
+import prog8.codegen.target.Cx16Target
 import java.io.File
 import java.nio.file.FileSystems
 import java.nio.file.Path
@@ -36,10 +37,14 @@ private fun compileMain(args: Array<String>): Boolean {
     val outputDir by cli.option(ArgType.String, fullName = "out", description = "directory for output files instead of current directory").default(".")
     val dontWriteAssembly by cli.option(ArgType.Boolean, fullName = "noasm", description="don't create assembly code")
     val dontOptimize by cli.option(ArgType.Boolean, fullName = "noopt", description = "don't perform any optimizations")
+    val dontReinitGlobals by cli.option(ArgType.Boolean, fullName = "noreinit", description = "don't create code to reinitialize globals on multiple runs of the program (experimental!)")
+    val optimizeFloatExpressions by cli.option(ArgType.Boolean, fullName = "optfloatx", description = "optimize float expressions (warning: can increase program size)")
     val watchMode by cli.option(ArgType.Boolean, fullName = "watch", description = "continuous compilation mode (watches for file changes), greatly increases compilation speed")
     val slowCodegenWarnings by cli.option(ArgType.Boolean, fullName = "slowwarn", description="show debug warnings about slow/problematic assembly code generation")
-    val compilationTarget by cli.option(ArgType.String, fullName = "target", description = "target output of the compiler, currently '${C64Target.name}' and '${Cx16Target.name}' available").default(C64Target.name)
-    val sourceDirs by cli.option(ArgType.String, fullName="srcdirs", description = "list of extra paths to search in for imported modules").multiple().delimiter(File.pathSeparator)
+    val quietAssembler by cli.option(ArgType.Boolean, fullName = "quietasm", description = "don't print assembler output results")
+    val asmListfile by cli.option(ArgType.Boolean, fullName = "asmlist", description = "make the assembler produce a listing file as well")
+    val compilationTarget by cli.option(ArgType.String, fullName = "target", description = "target output of the compiler (one of '${C64Target.name}', '${C128Target.name}', '${Cx16Target.name}')").default(C64Target.name)
+    val sourceDirs by cli.option(ArgType.String, fullName="srcdirs", description = "list of extra paths, separated with ${File.pathSeparator}, to search in for imported modules").multiple().delimiter(File.pathSeparator)
     val moduleFiles by cli.argument(ArgType.String, fullName = "modules", description = "main module file(s) to compile").multiple(999)
 
     try {
@@ -65,6 +70,11 @@ private fun compileMain(args: Array<String>): Boolean {
     if(srcdirs.firstOrNull()!=".")
         srcdirs.add(0, ".")
 
+    if (compilationTarget !in setOf(C64Target.name, C128Target.name, Cx16Target.name)) {
+        System.err.println("Invalid compilation target: $compilationTarget")
+        return false
+    }
+
     if(watchMode==true) {
         val watchservice = FileSystems.getDefault().newWatchService()
         val allImportedFiles = mutableSetOf<Path>()
@@ -74,7 +84,20 @@ private fun compileMain(args: Array<String>): Boolean {
             val results = mutableListOf<CompilationResult>()
             for(filepathRaw in moduleFiles) {
                 val filepath = pathFrom(filepathRaw).normalize()
-                val compilationResult = compileProgram(filepath, dontOptimize!=true, dontWriteAssembly!=true, slowCodegenWarnings==true, compilationTarget, srcdirs, outputPath)
+                val compilerArgs = CompilerArguments(
+                    filepath,
+                    dontOptimize != true,
+                    optimizeFloatExpressions == true,
+                    dontReinitGlobals == true,
+                    dontWriteAssembly != true,
+                    slowCodegenWarnings == true,
+                    quietAssembler == true,
+                    asmListfile == true,
+                    compilationTarget,
+                    srcdirs,
+                    outputPath
+                )
+                val compilationResult = compileProgram(compilerArgs)
                 results.add(compilationResult)
             }
 
@@ -111,11 +134,22 @@ private fun compileMain(args: Array<String>): Boolean {
             val filepath = pathFrom(filepathRaw).normalize()
             val compilationResult: CompilationResult
             try {
-                compilationResult = compileProgram(filepath, dontOptimize!=true, dontWriteAssembly!=true, slowCodegenWarnings==true, compilationTarget, srcdirs, outputPath)
-                if(!compilationResult.success)
+                val compilerArgs = CompilerArguments(
+                    filepath,
+                    dontOptimize != true,
+                    optimizeFloatExpressions == true,
+                    dontReinitGlobals == true,
+                    dontWriteAssembly != true,
+                    slowCodegenWarnings == true,
+                    quietAssembler == true,
+                    asmListfile == true,
+                    compilationTarget,
+                    srcdirs,
+                    outputPath
+                )
+                compilationResult = compileProgram(compilerArgs)
+                if (!compilationResult.success)
                     return false
-            } catch (x: ParsingFailedError) {
-                return false
             } catch (x: AstException) {
                 return false
             }

compiler/src/prog8/compiler/AssemblyError.kt

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

compiler/src/prog8/compiler/BeforeAsmGenerationAstChanger.kt

@@ -1,355 +0,0 @@
-package prog8.compiler
-
-import prog8.ast.IFunctionCall
-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.ast.walk.IAstVisitor
-import prog8.compiler.astprocessing.isInRegularRAMof
-import prog8.compiler.target.ICompilationTarget
-
-
-internal class BeforeAsmGenerationAstChanger(val program: Program, val errors: IErrorReporter, private val compTarget: ICompilationTarget) : AstWalker() {
-
-    override fun after(decl: VarDecl, parent: Node): Iterable<IAstModification> {
-        subroutineVariables.add(decl.name to decl)
-        if (decl.value == null && !decl.autogeneratedDontRemove && decl.type == VarDeclType.VAR && decl.datatype in NumericDatatypes) {
-            // A numeric vardecl without an initial value is initialized with zero,
-            // unless there's already an assignment below, that initializes the value.
-            // This allows you to restart the program and have the same starting values of the variables
-            if(decl.allowInitializeWithZero)
-            {
-                val nextAssign = decl.definingScope.nextSibling(decl) as? Assignment
-                if (nextAssign != null && nextAssign.target isSameAs IdentifierReference(listOf(decl.name), Position.DUMMY))
-                    decl.value = null
-                else {
-                    decl.value = decl.zeroElementValue()
-                }
-            }
-        }
-        return noModifications
-    }
-
-    override fun after(assignment: Assignment, parent: Node): Iterable<IAstModification> {
-        // Try to replace A = B <operator> Something  by A= B, A = A <operator> Something
-        // this triggers the more efficent augmented assignment code generation more often.
-        // But it can only be done if the target variable IS NOT OCCURRING AS AN OPERAND ITSELF.
-        if(!assignment.isAugmentable
-                && assignment.target.identifier != null
-                && assignment.target.isInRegularRAMof(compTarget.machine)) {
-            val binExpr = assignment.value as? BinaryExpression
-            if (binExpr != null && binExpr.operator !in comparisonOperators) {
-                if (binExpr.left !is BinaryExpression) {
-                    if (binExpr.right.referencesIdentifier(*assignment.target.identifier!!.nameInSource.toTypedArray())) {
-                        // the right part of the expression contains the target variable itself.
-                        // we can't 'split' it trivially because the variable will be changed halfway through.
-                        if(binExpr.operator in associativeOperators) {
-                            // A = <something-without-A>  <associativeoperator>  <otherthing-with-A>
-                            // use the other part of the expression to split.
-                            val assignRight = Assignment(assignment.target, binExpr.right, assignment.position)
-                            return listOf(
-                                    IAstModification.InsertBefore(assignment, assignRight, assignment.definingScope),
-                                    IAstModification.ReplaceNode(binExpr.right, binExpr.left, binExpr),
-                                    IAstModification.ReplaceNode(binExpr.left, assignment.target.toExpression(), binExpr))
-                        }
-                    } else {
-                        val assignLeft = Assignment(assignment.target, binExpr.left, assignment.position)
-                        return listOf(
-                                IAstModification.InsertBefore(assignment, assignLeft, assignment.definingScope),
-                                IAstModification.ReplaceNode(binExpr.left, assignment.target.toExpression(), binExpr))
-                    }
-                }
-            }
-        }
-        return noModifications
-    }
-
-    private val subroutineVariables = mutableListOf<Pair<String, VarDecl>>()
-    private val addedIfConditionVars = mutableSetOf<Pair<Subroutine, String>>()
-
-    override fun before(subroutine: Subroutine, parent: Node): Iterable<IAstModification> {
-        subroutineVariables.clear()
-        addedIfConditionVars.clear()
-        return noModifications
-    }
-
-    override fun after(scope: AnonymousScope, parent: Node): Iterable<IAstModification> {
-        val decls = scope.statements.filterIsInstance<VarDecl>().filter { it.type == VarDeclType.VAR }
-        subroutineVariables.addAll(decls.map { it.name to it })
-
-        val sub = scope.definingSubroutine
-        if (sub != null) {
-            // move any remaining vardecls of the scope into the upper scope. Make sure the position remains the same!
-            val replacements = mutableListOf<IAstModification>()
-            val movements = mutableListOf<IAstModification.InsertFirst>()
-
-            for(decl in decls) {
-                if(decl.value!=null && decl.datatype in NumericDatatypes) {
-                    val target = AssignTarget(IdentifierReference(listOf(decl.name), decl.position), null, null, decl.position)
-                    val assign = Assignment(target, decl.value!!, decl.position)
-                    replacements.add(IAstModification.ReplaceNode(decl, assign, scope))
-                    decl.value = null
-                    decl.allowInitializeWithZero = false
-                } else {
-                    replacements.add(IAstModification.Remove(decl, scope))
-                }
-                movements.add(IAstModification.InsertFirst(decl, sub))
-            }
-            return replacements + movements
-        }
-        return noModifications
-    }
-
-    override fun after(subroutine: Subroutine, parent: Node): Iterable<IAstModification> {
-        val firstDeclarations = mutableMapOf<String, VarDecl>()
-        for(decl in subroutineVariables) {
-            val existing = firstDeclarations[decl.first]
-            if(existing!=null && existing !== decl.second) {
-                errors.err("variable ${decl.first} already defined in subroutine ${subroutine.name} at ${existing.position}", decl.second.position)
-            } else {
-                firstDeclarations[decl.first] = decl.second
-            }
-        }
-
-
-        // add the implicit return statement at the end (if it's not there yet), but only if it's not a kernal routine.
-        // and if an assembly block doesn't contain a rts/rti, and some other situations.
-        val mods = mutableListOf<IAstModification>()
-        val returnStmt = Return(null, subroutine.position)
-        if (subroutine.asmAddress == null && !subroutine.inline) {
-            if(subroutine.statements.isEmpty() ||
-                (subroutine.amountOfRtsInAsm() == 0
-                && subroutine.statements.lastOrNull { it !is VarDecl } !is Return
-                && subroutine.statements.last() !is Subroutine)) {
-                    mods += IAstModification.InsertLast(returnStmt, subroutine)
-            }
-        }
-
-        // precede a subroutine with a return to avoid falling through into the subroutine from code above it
-        val outerScope = subroutine.definingScope
-        val outerStatements = outerScope.statements
-        val subroutineStmtIdx = outerStatements.indexOf(subroutine)
-        if (subroutineStmtIdx > 0
-                && outerStatements[subroutineStmtIdx - 1] !is Jump
-                && outerStatements[subroutineStmtIdx - 1] !is Subroutine
-                && outerStatements[subroutineStmtIdx - 1] !is Return
-                && outerScope !is Block) {
-            mods += IAstModification.InsertAfter(outerStatements[subroutineStmtIdx - 1], returnStmt, outerScope)
-        }
-        return mods
-    }
-
-    override fun after(typecast: TypecastExpression, parent: Node): Iterable<IAstModification> {
-        // see if we can remove superfluous typecasts (outside of expressions)
-        // such as casting byte<->ubyte,  word<->uword
-        // Also the special typecast of a reference type (str, array) to an UWORD will be changed into address-of.
-        val sourceDt = typecast.expression.inferType(program).getOr(DataType.UNDEFINED)
-        if (typecast.type in ByteDatatypes && sourceDt in ByteDatatypes
-                || typecast.type in WordDatatypes && sourceDt in WordDatatypes) {
-            if(typecast.parent !is Expression) {
-                return listOf(IAstModification.ReplaceNode(typecast, typecast.expression, parent))
-            }
-        }
-
-
-        // Note: for various reasons (most importantly, code simplicity), the code generator assumes/requires
-        // that the types of assignment values and their target are the same,
-        // and that the types of both operands of a binaryexpression node are the same.
-        // So, it is not easily possible to remove the typecasts that are there to make these conditions true.
-        // The only place for now where we can do this is for:
-        //    asmsub register pair parameter.
-
-        if(sourceDt in PassByReferenceDatatypes) {
-            if(typecast.type==DataType.UWORD) {
-                if(typecast.expression is IdentifierReference) {
-                    return listOf(IAstModification.ReplaceNode(
-                            typecast,
-                            AddressOf(typecast.expression as IdentifierReference, typecast.position),
-                            parent
-                    ))
-                } else if(typecast.expression is IFunctionCall) {
-                    return listOf(IAstModification.ReplaceNode(
-                            typecast,
-                            typecast.expression,
-                            parent
-                    ))
-                }
-            } else {
-                errors.err("cannot cast pass-by-reference value to type ${typecast.type} (only to UWORD)", typecast.position)
-            }
-        }
-
-        return noModifications
-    }
-
-    override fun after(ifStatement: IfStatement, parent: Node): Iterable<IAstModification> {
-        val binExpr = ifStatement.condition as? BinaryExpression
-        if(binExpr==null || binExpr.operator !in comparisonOperators) {
-            // if x  ->  if x!=0,    if x+5  ->  if x+5 != 0
-            val booleanExpr = BinaryExpression(ifStatement.condition, "!=", NumericLiteralValue.optimalInteger(0, ifStatement.condition.position), ifStatement.condition.position)
-            return listOf(IAstModification.ReplaceNode(ifStatement.condition, booleanExpr, ifStatement))
-        }
-
-        if((binExpr.operator=="==" || binExpr.operator=="!=") &&
-            (binExpr.left as? NumericLiteralValue)?.number==0 &&
-            (binExpr.right as? NumericLiteralValue)?.number!=0)
-            throw CompilerException("if 0==X should have been swapped to if X==0")
-
-        // split the conditional expression into separate variables if the operand(s) is not simple.
-        // DISABLED FOR NOW AS IT GENEREATES LARGER CODE IN THE SIMPLE CASES LIKE    IF X {...}  or  IF NOT X {...}
-//        val modifications = mutableListOf<IAstModification>()
-//        if(!binExpr.left.isSimple) {
-//            val sub = binExpr.definingSubroutine()!!
-//            val (variable, isNew, assignment) = addIfOperandVar(sub, "left", binExpr.left)
-//            if(isNew)
-//                modifications.add(IAstModification.InsertFirst(variable, sub))
-//            modifications.add(IAstModification.InsertBefore(ifStatement, assignment, parent as INameScope))
-//            modifications.add(IAstModification.ReplaceNode(binExpr.left, IdentifierReference(listOf(variable.name), binExpr.position), binExpr))
-//            addedIfConditionVars.add(Pair(sub, variable.name))
-//        }
-//        if(!binExpr.right.isSimple) {
-//            val sub = binExpr.definingSubroutine()!!
-//            val (variable, isNew, assignment) = addIfOperandVar(sub, "right", binExpr.right)
-//            if(isNew)
-//                modifications.add(IAstModification.InsertFirst(variable, sub))
-//            modifications.add(IAstModification.InsertBefore(ifStatement, assignment, parent as INameScope))
-//            modifications.add(IAstModification.ReplaceNode(binExpr.right, IdentifierReference(listOf(variable.name), binExpr.position), binExpr))
-//            addedIfConditionVars.add(Pair(sub, variable.name))
-//        }
-//        return modifications
-        return noModifications
-    }
-
-//    private fun addIfOperandVar(sub: Subroutine, side: String, operand: Expression): Triple<VarDecl, Boolean, Assignment> {
-//        val dt = operand.inferType(program).typeOrElse(DataType.UNDEFINED)
-//        val varname = "prog8_ifvar_${side}_${dt.name.toLowerCase()}"
-//        val tgt = AssignTarget(IdentifierReference(listOf(varname), operand.position), null, null, operand.position)
-//        val assign = Assignment(tgt, operand, operand.position)
-//        if(Pair(sub, varname) in addedIfConditionVars) {
-//            val vardecl = VarDecl(VarDeclType.VAR, dt, ZeropageWish.DONTCARE, null, varname, null, null, false, true, operand.position)
-//            return Triple(vardecl, false, assign)
-//        }
-//        val existing = sub.statements.firstOrNull { it is VarDecl && it.name == varname} as VarDecl?
-//        return if (existing == null) {
-//            val vardecl = VarDecl(VarDeclType.VAR, dt, ZeropageWish.DONTCARE, null, varname, null, null, false, true, operand.position)
-//            Triple(vardecl, true, assign)
-//        } else {
-//            Triple(existing, false, assign)
-//        }
-//    }
-
-    override fun after(untilLoop: UntilLoop, parent: Node): Iterable<IAstModification> {
-        val binExpr = untilLoop.condition as? BinaryExpression
-        if(binExpr==null || binExpr.operator !in comparisonOperators) {
-            // until x  ->  until x!=0,    until x+5  ->  until x+5 != 0
-            val booleanExpr = BinaryExpression(untilLoop.condition, "!=", NumericLiteralValue.optimalInteger(0, untilLoop.condition.position), untilLoop.condition.position)
-            return listOf(IAstModification.ReplaceNode(untilLoop.condition, booleanExpr, untilLoop))
-        }
-        return noModifications
-    }
-
-    override fun after(whileLoop: WhileLoop, parent: Node): Iterable<IAstModification> {
-        val binExpr = whileLoop.condition as? BinaryExpression
-        if(binExpr==null || binExpr.operator !in comparisonOperators) {
-            // while x  ->  while x!=0,    while x+5  ->  while x+5 != 0
-            val booleanExpr = BinaryExpression(whileLoop.condition, "!=", NumericLiteralValue.optimalInteger(0, whileLoop.condition.position), whileLoop.condition.position)
-            return listOf(IAstModification.ReplaceNode(whileLoop.condition, booleanExpr, whileLoop))
-        }
-        return noModifications
-    }
-
-    override fun after(functionCallStatement: FunctionCallStatement, parent: Node): Iterable<IAstModification> {
-        if(functionCallStatement.target.nameInSource==listOf("cmp")) {
-            // if the datatype of the arguments of cmp() are different, cast the byte one to word.
-            val arg1 = functionCallStatement.args[0]
-            val arg2 = functionCallStatement.args[1]
-            val dt1 = arg1.inferType(program).getOr(DataType.UNDEFINED)
-            val dt2 = arg2.inferType(program).getOr(DataType.UNDEFINED)
-            if(dt1 in ByteDatatypes) {
-                if(dt2 in ByteDatatypes)
-                    return noModifications
-                val cast1 = TypecastExpression(arg1, if(dt1==DataType.UBYTE) DataType.UWORD else DataType.WORD, true, functionCallStatement.position)
-                return listOf(IAstModification.ReplaceNode(arg1, cast1, functionCallStatement))
-            } else {
-                if(dt2 in WordDatatypes)
-                    return noModifications
-                val cast2 = TypecastExpression(arg2, if(dt2==DataType.UBYTE) DataType.UWORD else DataType.WORD, true, functionCallStatement.position)
-                return listOf(IAstModification.ReplaceNode(arg2, cast2, functionCallStatement))
-            }
-        }
-        return noModifications
-    }
-
-    override fun after(arrayIndexedExpression: ArrayIndexedExpression, parent: Node): Iterable<IAstModification> {
-
-        val containingStatement = getContainingStatement(arrayIndexedExpression)
-        if(getComplexArrayIndexedExpressions(containingStatement).size > 1) {
-            errors.err("it's not possible to use more than one complex array indexing expression in a single statement; break it up via a temporary variable for instance", containingStatement.position)
-            return noModifications
-        }
-
-
-        val index = arrayIndexedExpression.indexer.indexExpr
-        if(index !is NumericLiteralValue && index !is IdentifierReference) {
-            // replace complex indexing expression with a temp variable to hold the computed index first
-            return getAutoIndexerVarFor(arrayIndexedExpression)
-        }
-
-        return noModifications
-    }
-
-    private fun getComplexArrayIndexedExpressions(stmt: Statement): List<ArrayIndexedExpression> {
-
-        class Searcher : IAstVisitor {
-            val complexArrayIndexedExpressions = mutableListOf<ArrayIndexedExpression>()
-            override fun visit(arrayIndexedExpression: ArrayIndexedExpression) {
-                val ix = arrayIndexedExpression.indexer.indexExpr
-                if(ix !is NumericLiteralValue && ix !is IdentifierReference)
-                    complexArrayIndexedExpressions.add(arrayIndexedExpression)
-            }
-
-            override fun visit(branchStatement: BranchStatement) {}
-
-            override fun visit(forLoop: ForLoop) {}
-
-            override fun visit(ifStatement: IfStatement) {
-                ifStatement.condition.accept(this)
-            }
-
-            override fun visit(untilLoop: UntilLoop) {
-                untilLoop.condition.accept(this)
-            }
-        }
-
-        val searcher = Searcher()
-        stmt.accept(searcher)
-        return searcher.complexArrayIndexedExpressions
-    }
-
-    private fun getContainingStatement(expression: Expression): Statement {
-        var node: Node = expression
-        while(node !is Statement)
-            node = node.parent
-
-        return node
-    }
-
-    private fun getAutoIndexerVarFor(expr: ArrayIndexedExpression): MutableList<IAstModification> {
-        val modifications = mutableListOf<IAstModification>()
-        val statement = expr.containingStatement
-        val dt = expr.indexer.indexExpr.inferType(program)
-        val register = if(dt istype DataType.UBYTE  || dt istype DataType.BYTE ) "r9L" else "r9"
-        // replace the indexer with just the variable (simply use a cx16 virtual register r9, that we HOPE is not used for other things in the expression...)
-        // assign the indexing expression to the helper variable, but only if that hasn't been done already
-        val target = AssignTarget(IdentifierReference(listOf("cx16", register), expr.indexer.position), null, null, expr.indexer.position)
-        val assign = Assignment(target, expr.indexer.indexExpr, expr.indexer.position)
-        modifications.add(IAstModification.InsertBefore(statement, assign, statement.definingScope))
-        modifications.add(IAstModification.ReplaceNode(expr.indexer.indexExpr, target.identifier!!.copy(), expr.indexer))
-        return modifications
-    }
-
-}

compiler/src/prog8/compiler/Compiler.kt

@@ -1,87 +1,59 @@
 package prog8.compiler
 
 import com.github.michaelbull.result.*
-import prog8.ast.AstToSourceCode
+import prog8.ast.AstToSourceTextConverter
 import prog8.ast.IBuiltinFunctions
-import prog8.ast.IMemSizer
 import prog8.ast.Program
 import prog8.ast.base.AstException
 import prog8.ast.base.Position
 import prog8.ast.expressions.Expression
 import prog8.ast.expressions.NumericLiteralValue
 import prog8.ast.statements.Directive
+import prog8.codegen.target.C128Target
 import prog8.compiler.astprocessing.*
-import prog8.compiler.functions.*
-import prog8.compiler.target.C64Target
-import prog8.compiler.target.Cx16Target
-import prog8.compiler.target.ICompilationTarget
-import prog8.compiler.target.asmGeneratorFor
+import prog8.codegen.target.C64Target
+import prog8.codegen.target.Cx16Target
+import prog8.codegen.target.cpu6502.codegen.AsmGen
+import prog8.compilerinterface.*
 import prog8.optimizer.*
 import prog8.parser.ParseError
-import prog8.parser.ParsingFailedError
-import prog8.parser.SourceCode
-import prog8.parser.SourceCode.Companion.libraryFilePrefix
-import java.io.File
 import java.nio.file.Path
 import kotlin.io.path.Path
 import kotlin.io.path.nameWithoutExtension
 import kotlin.system.measureTimeMillis
 
 
-enum class OutputType {
-    RAW,
-    PRG
-}
-
-enum class LauncherType {
-    BASIC,
-    NONE
-}
-
-enum class ZeropageType {
-    BASICSAFE,
-    FLOATSAFE,
-    KERNALSAFE,
-    FULL,
-    DONTUSE
-}
-
-data class CompilationOptions(val output: OutputType,
-                              val launcher: LauncherType,
-                              val zeropage: ZeropageType,
-                              val zpReserved: List<IntRange>,
-                              val floats: Boolean,
-                              val noSysInit: Boolean,
-                              val compTarget: ICompilationTarget) {
-    var slowCodegenWarnings = false
-    var optimize = false
-}
-
-
-class CompilerException(message: String?) : Exception(message)
-
 class CompilationResult(val success: Boolean,
-                        val programAst: Program,
+                        val program: Program,
                         val programName: String,
                         val compTarget: ICompilationTarget,
                         val importedFiles: List<Path>)
 
+class CompilerArguments(val filepath: Path,
+                        val optimize: Boolean,
+                        val optimizeFloatExpressions: Boolean,
+                        val dontReinitGlobals: Boolean,
+                        val writeAssembly: Boolean,
+                        val slowCodegenWarnings: Boolean,
+                        val quietAssembler: Boolean,
+                        val asmListfile: Boolean,
+                        val compilationTarget: String,
+                        val sourceDirs: List<String> = emptyList(),
+                        val outputDir: Path = Path(""),
+                        val errors: IErrorReporter = ErrorReporter())
 
-fun compileProgram(filepath: Path,
-                   optimize: Boolean,
-                   writeAssembly: Boolean,
-                   slowCodegenWarnings: Boolean,
-                   compilationTarget: String,
-                   sourceDirs: List<String>,
-                   outputDir: Path): CompilationResult {
+
+fun compileProgram(args: CompilerArguments): CompilationResult {
     var programName = ""
-    lateinit var programAst: Program
+    lateinit var program: Program
     lateinit var importedFiles: List<Path>
-    val errors = ErrorReporter()
+
+    val optimizeFloatExpr = if(args.optimize) args.optimizeFloatExpressions else false
 
     val compTarget =
-        when(compilationTarget) {
+        when(args.compilationTarget) {
             C64Target.name -> C64Target
+            C128Target.name -> C128Target
             Cx16Target.name -> Cx16Target
             else -> throw IllegalArgumentException("invalid compilation target")
         }
@@ -89,31 +61,41 @@ fun compileProgram(filepath: Path,
     try {
         val totalTime = measureTimeMillis {
             // import main module and everything it needs
-            val (ast, compilationOptions, imported) = parseImports(filepath, errors, compTarget, sourceDirs)
-            compilationOptions.slowCodegenWarnings = slowCodegenWarnings
-            compilationOptions.optimize = optimize
-            programAst = ast
+            val (programresult, compilationOptions, imported) = parseImports(args.filepath, args.errors, compTarget, args.sourceDirs)
+            with(compilationOptions) {
+                slowCodegenWarnings = args.slowCodegenWarnings
+                optimize = args.optimize
+                optimizeFloatExpressions = optimizeFloatExpr
+                dontReinitGlobals = args.dontReinitGlobals
+                asmQuiet = args.quietAssembler
+                asmListfile = args.asmListfile
+            }
+            program = programresult
             importedFiles = imported
-            processAst(programAst, errors, compilationOptions)
-            if (compilationOptions.optimize)
+            processAst(program, args.errors, compilationOptions)
+            if (compilationOptions.optimize) {
+//                println("*********** AST RIGHT BEFORE OPTIMIZING *************")
+//                printProgram(program)
+
                 optimizeAst(
-                    programAst,
-                    errors,
+                    program,
+                    compilationOptions,
+                    args.errors,
                     BuiltinFunctionsFacade(BuiltinFunctions),
-                    compTarget,
-                    compilationOptions
+                    compTarget
                 )
-            postprocessAst(programAst, errors, compilationOptions)
+            }
+            postprocessAst(program, args.errors, compilationOptions)
 
-            // printAst(programAst)
+//            println("*********** AST BEFORE ASSEMBLYGEN *************")
+//            printProgram(program)
 
-            if (writeAssembly) {
-                val result = writeAssembly(programAst, errors, outputDir, compilationOptions)
-                when (result) {
+            if (args.writeAssembly) {
+                when (val result = writeAssembly(program, args.errors, args.outputDir, compilationOptions)) {
                     is WriteAssemblyResult.Ok -> programName = result.filename
                     is WriteAssemblyResult.Fail -> {
                         System.err.println(result.error)
-                        return CompilationResult(false, programAst, programName, compTarget, importedFiles)
+                        return CompilationResult(false, program, programName, compTarget, importedFiles)
                     }
                 }
             }
@@ -121,14 +103,20 @@ fun compileProgram(filepath: Path,
         System.out.flush()
         System.err.flush()
         println("\nTotal compilation+assemble time: ${totalTime / 1000.0} sec.")
-        return CompilationResult(true, programAst, programName, compTarget, importedFiles)
+        return CompilationResult(true, program, programName, compTarget, importedFiles)
     } catch (px: ParseError) {
         System.err.print("\u001b[91m")  // bright red
         System.err.println("${px.position.toClickableStr()} parse error: ${px.message}".trim())
         System.err.print("\u001b[0m")  // reset
-    } catch (pfx: ParsingFailedError) {
+    } catch (ac: AbortCompilation) {
+        if(!ac.message.isNullOrEmpty()) {
+            System.err.print("\u001b[91m")  // bright red
+            System.err.println(ac.message)
+            System.err.print("\u001b[0m")  // reset
+        }
+    } catch (nsf: NoSuchFileException) {
         System.err.print("\u001b[91m")  // bright red
-        System.err.println(pfx.message)
+        System.err.println("File not found: ${nsf.message}")
         System.err.print("\u001b[0m")  // reset
     } catch (ax: AstException) {
         System.err.print("\u001b[91m")  // bright red
@@ -148,7 +136,7 @@ fun compileProgram(filepath: Path,
         throw x
     }
 
-    val failedProgram = Program("failed", BuiltinFunctionsFacade(BuiltinFunctions), compTarget)
+    val failedProgram = Program("failed", BuiltinFunctionsFacade(BuiltinFunctions), compTarget, compTarget)
     return CompilationResult(false, failedProgram, programName, compTarget, emptyList())
 }
 
@@ -158,13 +146,13 @@ private class BuiltinFunctionsFacade(functions: Map<String, FSignature>): IBuilt
     override val names = functions.keys
     override val purefunctionNames = functions.filter { it.value.pure }.map { it.key }.toSet()
 
-    override fun constValue(name: String, args: List<Expression>, position: Position, memsizer: IMemSizer): NumericLiteralValue? {
+    override fun constValue(name: String, args: List<Expression>, position: Position): NumericLiteralValue? {
         val func = BuiltinFunctions[name]
         if(func!=null) {
             val exprfunc = func.constExpressionFunc
             if(exprfunc!=null) {
                 return try {
-                    exprfunc(args, position, program, memsizer)
+                    exprfunc(args, position, program)
                 } catch(x: NotConstArgumentException) {
                     // const-evaluating the builtin function call failed.
                     null
@@ -188,21 +176,18 @@ fun parseImports(filepath: Path,
                  sourceDirs: List<String>): Triple<Program, CompilationOptions, List<Path>> {
     println("Compiler target: ${compTarget.name}. Parsing...")
     val bf = BuiltinFunctionsFacade(BuiltinFunctions)
-    val programAst = Program(filepath.nameWithoutExtension, bf, compTarget)
-    bf.program = programAst
+    val program = Program(filepath.nameWithoutExtension, bf, compTarget, compTarget)
+    bf.program = program
 
-    val importer = ModuleImporter(programAst, compTarget.name, errors, sourceDirs)
+    val importer = ModuleImporter(program, compTarget.name, errors, sourceDirs)
     val importedModuleResult = importer.importModule(filepath)
     importedModuleResult.onFailure { throw it }
     errors.report()
 
-    val importedFiles = programAst.modules.map { it.source }
+    val importedFiles = program.modules.map { it.source }
         .filter { it.isFromFilesystem }
         .map { Path(it.origin) }
-    val compilerOptions = determineCompilationOptions(programAst, compTarget)
-    if (compilerOptions.launcher == LauncherType.BASIC && compilerOptions.output != OutputType.PRG)
-        throw ParsingFailedError("${programAst.modules.first().position} BASIC launcher requires output type PRG.")
-
+    val compilerOptions = determineCompilationOptions(program, compTarget)
     // depending on the machine and compiler options we may have to include some libraries
     for(lib in compTarget.machine.importLibs(compilerOptions, compTarget.name))
         importer.importLibraryModule(lib)
@@ -210,8 +195,12 @@ fun parseImports(filepath: Path,
     // always import prog8_lib and math
     importer.importLibraryModule("math")
     importer.importLibraryModule("prog8_lib")
+
+    if (compilerOptions.launcher == LauncherType.BASIC && compilerOptions.output != OutputType.PRG)
+        errors.err("BASIC launcher requires output type PRG", program.toplevelModule.position)
     errors.report()
-    return Triple(programAst, compilerOptions, importedFiles)
+
+    return Triple(program, compilerOptions, importedFiles)
 }
 
 fun determineCompilationOptions(program: Program, compTarget: ICompilationTarget): CompilationOptions {
@@ -246,6 +235,7 @@ fun determineCompilationOptions(program: Program, compTarget: ICompilationTarget
         .asSequence()
         .filter { it is Directive && it.directive == "%zpreserved" }
         .map { (it as Directive).args }
+        .filter { it.size==2 && it[0].int!=null && it[1].int!=null }
         .map { it[0].int!!..it[1].int!! }
         .toList()
 
@@ -274,63 +264,66 @@ fun determineCompilationOptions(program: Program, compTarget: ICompilationTarget
     )
 }
 
-private fun processAst(programAst: Program, errors: IErrorReporter, compilerOptions: CompilationOptions) {
+private fun processAst(program: Program, errors: IErrorReporter, compilerOptions: CompilationOptions) {
     // perform initial syntax checks and processings
     println("Processing for target ${compilerOptions.compTarget.name}...")
-    programAst.checkIdentifiers(errors, compilerOptions)
+    program.preprocessAst(errors)
+    program.checkIdentifiers(errors, compilerOptions)
     errors.report()
     // TODO: turning char literals into UBYTEs via an encoding should really happen in code gen - but for that we'd need DataType.CHAR
-    // NOTE: we will then lose the opportunity to do constant-folding on any expression containing a char literal, but how often will those occur?
-    // Also they might be optimized away eventually in codegen or by the assembler even
-    programAst.charLiteralsToUByteLiterals(errors, compilerOptions.compTarget)
+    //       ...but what do we gain from this? We can leave it as it is now: where a char literal is no more than syntactic sugar for an UBYTE value.
+    //       By introduction a CHAR dt, we will also lose the opportunity to do constant-folding on any expression containing a char literal.
+    //       Yes this is different from strings that are only encoded in the code gen phase.
+    program.charLiteralsToUByteLiterals(compilerOptions.compTarget)
+    program.constantFold(errors, compilerOptions.compTarget)
     errors.report()
-    programAst.constantFold(errors, compilerOptions.compTarget)
+    program.desugaring(errors)
     errors.report()
-    programAst.reorderStatements(errors)
+    program.reorderStatements(errors, compilerOptions)
     errors.report()
-    programAst.addTypecasts(errors)
+    program.addTypecasts(errors, compilerOptions)
     errors.report()
-    programAst.variousCleanups(programAst, errors)
+    program.variousCleanups(errors, compilerOptions)
     errors.report()
-    programAst.checkValid(compilerOptions, errors, compilerOptions.compTarget)
+    program.checkValid(errors, compilerOptions)
     errors.report()
-    programAst.checkIdentifiers(errors, compilerOptions)
+    program.checkIdentifiers(errors, compilerOptions)
     errors.report()
 }
 
-private fun optimizeAst(programAst: Program, errors: IErrorReporter, functions: IBuiltinFunctions, compTarget: ICompilationTarget, options: CompilationOptions) {
+private fun optimizeAst(program: Program, compilerOptions: CompilationOptions, errors: IErrorReporter, functions: IBuiltinFunctions, compTarget: ICompilationTarget) {
     // optimize the parse tree
     println("Optimizing...")
 
-    val remover = UnusedCodeRemover(programAst, errors, compTarget)
-    remover.visit(programAst)
+    val remover = UnusedCodeRemover(program, errors, compTarget)
+    remover.visit(program)
     remover.applyModifications()
 
     while (true) {
         // keep optimizing expressions and statements until no more steps remain
-        val optsDone1 = programAst.simplifyExpressions()
-        val optsDone2 = programAst.splitBinaryExpressions(compTarget)
-        val optsDone3 = programAst.optimizeStatements(errors, functions, compTarget)
-        programAst.constantFold(errors, compTarget) // because simplified statements and expressions can result in more constants that can be folded away
+        val optsDone1 = program.simplifyExpressions(errors)
+        val optsDone2 = program.splitBinaryExpressions(compilerOptions, compTarget)
+        val optsDone3 = program.optimizeStatements(errors, functions, compTarget)
+        program.constantFold(errors, compTarget) // because simplified statements and expressions can result in more constants that can be folded away
         errors.report()
         if (optsDone1 + optsDone2 + optsDone3 == 0)
             break
     }
-
     errors.report()
 }
 
-private fun postprocessAst(programAst: Program, errors: IErrorReporter, compilerOptions: CompilationOptions) {
-    programAst.addTypecasts(errors)
+private fun postprocessAst(program: Program, errors: IErrorReporter, compilerOptions: CompilationOptions) {
+    program.desugaring(errors)
+    program.addTypecasts(errors, compilerOptions)
     errors.report()
-    programAst.variousCleanups(programAst, errors)
-    programAst.checkValid(compilerOptions, errors, compilerOptions.compTarget)          // check if final tree is still valid
-    errors.report()
-    val callGraph = CallGraph(programAst)
+    program.variousCleanups(errors, compilerOptions)
+    val callGraph = CallGraph(program)
     callGraph.checkRecursiveCalls(errors)
     errors.report()
-    programAst.verifyFunctionArgTypes()
-    programAst.moveMainAndStartToFirst()
+    program.verifyFunctionArgTypes()
+    program.moveMainAndStartToFirst()
+    program.checkValid(errors, compilerOptions)          // check if final tree is still valid
+    errors.report()
 }
 
 private sealed class WriteAssemblyResult {
@@ -338,58 +331,55 @@ private sealed class WriteAssemblyResult {
     class Fail(val error: String): WriteAssemblyResult()
 }
 
-private fun writeAssembly(programAst: Program,
+private fun writeAssembly(program: Program,
                           errors: IErrorReporter,
                           outputDir: Path,
-                          compilerOptions: CompilationOptions): WriteAssemblyResult {
+                          compilerOptions: CompilationOptions
+): WriteAssemblyResult {
     // asm generation directly from the Ast
-    programAst.processAstBeforeAsmGeneration(errors, compilerOptions.compTarget)
+    program.processAstBeforeAsmGeneration(compilerOptions, errors)
     errors.report()
 
-    // printAst(programAst)
+//    println("*********** AST RIGHT BEFORE ASM GENERATION *************")
+//    printProgram(program)
 
     compilerOptions.compTarget.machine.initializeZeropage(compilerOptions)
     val assembly = asmGeneratorFor(compilerOptions.compTarget,
-            programAst,
+            program,
             errors,
             compilerOptions.compTarget.machine.zeropage,
             compilerOptions,
             outputDir).compileToAssembly()
+    errors.report()
 
     return if(assembly.valid && errors.noErrors()) {
         val assemblerReturnStatus = assembly.assemble(compilerOptions)
         if(assemblerReturnStatus!=0)
             WriteAssemblyResult.Fail("assembler step failed with return code $assemblerReturnStatus")
         else {
-            errors.report()
             WriteAssemblyResult.Ok(assembly.name)
         }
     } else {
-        errors.report()
         WriteAssemblyResult.Fail("compiler failed with errors")
     }
 }
 
-fun printAst(programAst: Program) {
+fun printProgram(program: Program) {
     println()
-    val printer = AstToSourceCode(::print, programAst)
-    printer.visit(programAst)
+    val printer = AstToSourceTextConverter(::print, program)
+    printer.visit(program)
     println()
 }
 
-internal fun loadAsmIncludeFile(filename: String, source: SourceCode): Result<String, NoSuchFileException> {
-    return if (filename.startsWith(libraryFilePrefix)) {
-        return runCatching {
-            val stream = object {}.javaClass.getResourceAsStream("/prog8lib/${filename.substring(libraryFilePrefix.length)}") // TODO handle via SourceCode
-            stream!!.bufferedReader().use { r -> r.readText() }
-        }.mapError { NoSuchFileException(File(filename)) }
-    } else {
-        // first try in the isSameAs folder as where the containing file was imported from
-        val sib = Path(source.origin).resolveSibling(filename)
-
-        if (sib.toFile().isFile)
-            Ok(sib.toFile().readText())
-        else
-            Ok(File(filename).readText())
-    }
+internal fun asmGeneratorFor(
+    compTarget: ICompilationTarget,
+    program: Program,
+    errors: IErrorReporter,
+    zp: Zeropage,
+    options: CompilationOptions,
+    outputDir: Path
+): IAssemblyGenerator
+{
+    // at the moment we only have one code generation backend (for 6502 and 65c02)
+    return AsmGen(program, errors, zp, options, compTarget, outputDir)
 }

compiler/src/prog8/compiler/ErrorReporter.kt

@@ -1,16 +1,7 @@
 package prog8.compiler
 
 import prog8.ast.base.Position
-import prog8.parser.ParsingFailedError
-
-
-interface IErrorReporter {
-    fun err(msg: String, position: Position)
-    fun warn(msg: String, position: Position)
-    fun noErrors(): Boolean
-    fun report()
-}
-
+import prog8.compilerinterface.IErrorReporter
 
 internal class ErrorReporter: IErrorReporter {
     private enum class MessageSeverity {
@@ -33,24 +24,29 @@ internal class ErrorReporter: IErrorReporter {
         var numErrors = 0
         var numWarnings = 0
         messages.forEach {
-            when(it.severity) {
-                MessageSeverity.ERROR -> System.err.print("\u001b[91m")  // bright red
-                MessageSeverity.WARNING -> System.err.print("\u001b[93m")  // bright yellow
+            val printer = when(it.severity) {
+                MessageSeverity.WARNING -> System.out
+                MessageSeverity.ERROR -> System.err
             }
-            val msg = "${it.position.toClickableStr()} ${it.severity} ${it.message}".trim()
+            when(it.severity) {
+                MessageSeverity.ERROR -> printer.print("\u001b[91m")  // bright red
+                MessageSeverity.WARNING -> printer.print("\u001b[93m")  // bright yellow
+            }
+            val msg = "${it.severity} ${it.position.toClickableStr()} ${it.message}".trim()
             if(msg !in alreadyReportedMessages) {
-                System.err.println(msg)
+                printer.println(msg)
                 alreadyReportedMessages.add(msg)
                 when(it.severity) {
                     MessageSeverity.WARNING -> numWarnings++
                     MessageSeverity.ERROR -> numErrors++
                 }
             }
-            System.err.print("\u001b[0m")  // reset color
+            printer.print("\u001b[0m")      // reset color
         }
+        System.out.flush()
+        System.err.flush()
         messages.clear()
-        if(numErrors>0)
-            throw ParsingFailedError("There are $numErrors errors and $numWarnings warnings.")
+        finalizeNumErrors(numErrors, numWarnings)
     }
 
     override fun noErrors() = messages.none { it.severity==MessageSeverity.ERROR }

compiler/src/prog8/compiler/IStringEncoding.kt

@@ -1,6 +0,0 @@
-package prog8.compiler
-
-interface IStringEncoding {
-    fun encodeString(str: String, altEncoding: Boolean): List<Short>
-    fun decodeString(bytes: List<Short>, altEncoding: Boolean): String
-}

compiler/src/prog8/compiler/ModuleImporter.kt

@@ -7,6 +7,7 @@ import prog8.ast.base.Position
 import prog8.ast.base.SyntaxError
 import prog8.ast.statements.Directive
 import prog8.ast.statements.DirectiveArg
+import prog8.compilerinterface.IErrorReporter
 import prog8.parser.Prog8Parser
 import prog8.parser.SourceCode
 import java.io.File
@@ -33,7 +34,7 @@ class ModuleImporter(private val program: Program,
         val srcPath = when (candidates.size) {
             0 -> return Err(NoSuchFileException(
                     file = filePath.normalize().toFile(),
-                    reason = "searched in $searchIn"))
+                    reason = "Searched in $searchIn"))
             1 -> candidates.first()
             else -> candidates.first()  // when more candiates, pick the one from the first location
         }
@@ -42,20 +43,17 @@ class ModuleImporter(private val program: Program,
         println(logMsg)
 
         val module = importModule(SourceCode.File(srcPath))
-        return if(module==null)
-            Err(NoSuchFileException(srcPath.toFile()))
-        else
-            Ok(module)
+        return Ok(module)
     }
 
     fun importLibraryModule(name: String): Module? {
         val import = Directive("%import", listOf(
-                DirectiveArg("", name, 42, position = Position("<<<implicit-import>>>", 0, 0, 0))
+                DirectiveArg("", name, 42u, position = Position("<<<implicit-import>>>", 0, 0, 0))
         ), Position("<<<implicit-import>>>", 0, 0, 0))
         return executeImportDirective(import, null)
     }
 
-    private fun importModule(src: SourceCode) : Module? {
+    private fun importModule(src: SourceCode) : Module {
         val moduleAst = Prog8Parser.parseModule(src)
         program.addModule(moduleAst)
 
@@ -105,15 +103,14 @@ class ModuleImporter(private val program: Program,
                             importModule(it)
                         },
                         failure = {
-                            errors.err("no module found with name $moduleName", import.position)
+                            errors.err("no module found with name $moduleName. Searched in: $sourcePaths (and internal libraries)", import.position)
                             return null
                         }
                     )
                 }
             )
 
-        if(importedModule!=null)
-            removeDirectivesFromImportedModule(importedModule)
+        removeDirectivesFromImportedModule(importedModule)
         return importedModule
     }
 
@@ -142,7 +139,6 @@ class ModuleImporter(private val program: Program,
             } else {
                 val dropCurDir = if(sourcePaths.isNotEmpty() && sourcePaths[0].name == ".") 1 else 0
                 sourcePaths.drop(dropCurDir) +
-                // TODO: won't work until Prog8Parser is fixed s.t. it fully initializes the modules it returns. // hm, what won't work?)
                 listOf(Path(importingModule.position.file).parent ?: Path("")) +
                 listOf(Path(".", "prog8lib"))
             }
@@ -150,7 +146,7 @@ class ModuleImporter(private val program: Program,
         locations.forEach {
             try {
                 return Ok(SourceCode.File(it.resolve(fileName)))
-            } catch (e: NoSuchFileException) {
+            } catch (_: NoSuchFileException) {
             }
         }
 

compiler/src/prog8/compiler/Zeropage.kt

@@ -1,95 +0,0 @@
-package prog8.compiler
-
-import prog8.ast.base.*
-
-
-class ZeropageDepletedError(message: String) : Exception(message)
-
-
-abstract class Zeropage(protected val options: CompilationOptions) {
-
-    abstract val SCRATCH_B1 : Int      // temp storage for a single byte
-    abstract val SCRATCH_REG : Int     // temp storage for a register
-    abstract val SCRATCH_W1 : Int      // temp storage 1 for a word  $fb+$fc
-    abstract val SCRATCH_W2 : Int      // temp storage 2 for a word  $fb+$fc
-
-
-    private val allocations = mutableMapOf<Int, Pair<String, DataType>>()
-    val free = mutableListOf<Int>()     // subclasses must set this to the appropriate free locations.
-
-    val allowedDatatypes = NumericDatatypes
-
-    fun availableBytes() = if(options.zeropage==ZeropageType.DONTUSE) 0 else free.size
-    fun hasByteAvailable() = if(options.zeropage==ZeropageType.DONTUSE) false else free.isNotEmpty()
-    fun availableWords(): Int {
-        if(options.zeropage==ZeropageType.DONTUSE)
-            return 0
-
-        val words = free.windowed(2).filter { it[0] == it[1]-1 }
-        var nonOverlappingWordsCount = 0
-        var prevMsbLoc = -1
-        for(w in words) {
-            if(w[0]!=prevMsbLoc) {
-                nonOverlappingWordsCount++
-                prevMsbLoc = w[1]
-            }
-        }
-        return nonOverlappingWordsCount
-    }
-    fun hasWordAvailable(): Boolean {
-        if(options.zeropage==ZeropageType.DONTUSE)
-            return false
-
-        return free.windowed(2).any { it[0] == it[1] - 1 }
-    }
-
-    fun allocate(scopedname: String, datatype: DataType, position: Position?, errors: IErrorReporter): Int {
-        assert(scopedname.isEmpty() || !allocations.values.any { it.first==scopedname } ) {"scopedname can't be allocated twice"}
-
-        if(options.zeropage==ZeropageType.DONTUSE)
-            throw CompilerException("zero page usage has been disabled")
-
-        val size =
-                when (datatype) {
-                    in ByteDatatypes -> 1
-                    in WordDatatypes -> 2
-                    DataType.FLOAT -> {
-                        if (options.floats) {
-                            if(position!=null)
-                                errors.warn("allocated a large value (float) in zeropage", position)
-                            else
-                                errors.warn("$scopedname: allocated a large value (float) in zeropage", position ?: Position.DUMMY)
-                            5
-                        } else throw CompilerException("floating point option not enabled")
-                    }
-                    else -> throw CompilerException("cannot put datatype $datatype in zeropage")
-                }
-
-        if(free.size > 0) {
-            if(size==1) {
-                for(candidate in free.minOrNull()!! .. free.maxOrNull()!!+1) {
-                    if(loneByte(candidate))
-                        return makeAllocation(candidate, 1, datatype, scopedname)
-                }
-                return makeAllocation(free[0], 1, datatype, scopedname)
-            }
-            for(candidate in free.minOrNull()!! .. free.maxOrNull()!!+1) {
-                if (sequentialFree(candidate, size))
-                    return makeAllocation(candidate, size, datatype, scopedname)
-            }
-        }
-
-        throw ZeropageDepletedError("ERROR: no free space in ZP to allocate $size sequential bytes")
-    }
-
-    protected fun reserve(range: IntRange) = free.removeAll(range)
-
-    private fun makeAllocation(address: Int, size: Int, datatype: DataType, name: String?): Int {
-        free.removeAll(address until address+size)
-        allocations[address] = (name ?: "<unnamed>") to datatype
-        return address
-    }
-
-    private fun loneByte(address: Int) = address in free && address-1 !in free && address+1 !in free
-    private fun sequentialFree(address: Int, size: Int) = free.containsAll((address until address+size).toList())
-}

compiler/src/prog8/compiler/astprocessing/AstChecker.kt

@@ -1,37 +1,28 @@
 package prog8.compiler.astprocessing
 
-import prog8.ast.INameScope
-import prog8.ast.Module
-import prog8.ast.Program
+import prog8.ast.*
 import prog8.ast.base.*
 import prog8.ast.expressions.*
 import prog8.ast.statements.*
 import prog8.ast.walk.IAstVisitor
-import prog8.compiler.CompilationOptions
-import prog8.compiler.IErrorReporter
-import prog8.compiler.ZeropageType
-import prog8.compiler.functions.BuiltinFunctions
-import prog8.compiler.functions.builtinFunctionReturnType
-import prog8.compiler.target.ICompilationTarget
+import prog8.compilerinterface.*
 import java.io.CharConversionException
 import java.io.File
-import java.util.*
-import kotlin.io.path.*
+import kotlin.io.path.Path
 
 internal class AstChecker(private val program: Program,
-                          private val compilerOptions: CompilationOptions,
                           private val errors: IErrorReporter,
-                          private val compTarget: ICompilationTarget
+                          private val compilerOptions: CompilationOptions
 ) : IAstVisitor {
 
     override fun visit(program: Program) {
-        assert(program === this.program)
+        require(program === this.program)
         // there must be a single 'main' block with a 'start' subroutine for the program entry point.
         val mainBlocks = program.modules.flatMap { it.statements }.filter { b -> b is Block && b.name=="main" }.map { it as Block }
         if(mainBlocks.size>1)
             errors.err("more than one 'main' block", mainBlocks[0].position)
         if(mainBlocks.isEmpty())
-            errors.err("there is no 'main' block", program.modules.firstOrNull()?.position ?: program.position)
+            errors.err("there is no 'main' block", program.modules.firstOrNull()?.position ?: Position.DUMMY)
 
         for(mainBlock in mainBlocks) {
             val startSub = mainBlock.subScope("start") as? Subroutine
@@ -86,27 +77,27 @@ internal class AstChecker(private val program: Program,
         super.visit(returnStmt)
     }
 
-    override fun visit(ifStatement: IfStatement) {
-        if(!ifStatement.condition.inferType(program).isInteger)
-            errors.err("condition value should be an integer type", ifStatement.condition.position)
-        super.visit(ifStatement)
+    override fun visit(ifElse: IfElse) {
+        if(!ifElse.condition.inferType(program).isInteger)
+            errors.err("condition value should be an integer type", ifElse.condition.position)
+        super.visit(ifElse)
     }
 
     override fun visit(forLoop: ForLoop) {
 
-        fun checkUnsignedLoopDownto0(range: RangeExpr?) {
+        fun checkUnsignedLoopDownto0(range: RangeExpression?) {
             if(range==null)
                 return
-            val step = range.step.constValue(program)?.number?.toDouble() ?: 1.0
+            val step = range.step.constValue(program)?.number ?: 1.0
             if(step < -1.0) {
-                val limit = range.to.constValue(program)?.number?.toDouble()
+                val limit = range.to.constValue(program)?.number
                 if(limit==0.0 && range.from.constValue(program)==null)
                     errors.err("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", forLoop.position)
             }
         }
 
         val iterableDt = forLoop.iterable.inferType(program).getOr(DataType.BYTE)
-        if(iterableDt !in IterableDatatypes && forLoop.iterable !is RangeExpr) {
+        if(iterableDt !in IterableDatatypes && forLoop.iterable !is RangeExpression) {
             errors.err("can only loop over an iterable type", forLoop.position)
         } else {
             val loopvar = forLoop.loopVar.targetVarDecl(program)
@@ -118,14 +109,14 @@ internal class AstChecker(private val program: Program,
                         if(iterableDt!= DataType.UBYTE && iterableDt!= DataType.ARRAY_UB && iterableDt != DataType.STR)
                             errors.err("ubyte loop variable can only loop over unsigned bytes or strings", forLoop.position)
 
-                        checkUnsignedLoopDownto0(forLoop.iterable as? RangeExpr)
+                        checkUnsignedLoopDownto0(forLoop.iterable as? RangeExpression)
                     }
                     DataType.UWORD -> {
                         if(iterableDt!= DataType.UBYTE && iterableDt!= DataType.UWORD && iterableDt != DataType.STR &&
                                 iterableDt != DataType.ARRAY_UB && iterableDt!= DataType.ARRAY_UW)
                             errors.err("uword loop variable can only loop over unsigned bytes, words or strings", forLoop.position)
 
-                        checkUnsignedLoopDownto0(forLoop.iterable as? RangeExpr)
+                        checkUnsignedLoopDownto0(forLoop.iterable as? RangeExpression)
                     }
                     DataType.BYTE -> {
                         if(iterableDt!= DataType.BYTE && iterableDt!= DataType.ARRAY_B)
@@ -146,7 +137,7 @@ internal class AstChecker(private val program: Program,
                 }
                 if(errors.noErrors()) {
                     // check loop range values
-                    val range = forLoop.iterable as? RangeExpr
+                    val range = forLoop.iterable as? RangeExpression
                     if(range!=null) {
                         val from = range.from as? NumericLiteralValue
                         val to = range.to as? NumericLiteralValue
@@ -166,26 +157,44 @@ internal class AstChecker(private val program: Program,
         super.visit(forLoop)
     }
 
-
     override fun visit(jump: Jump) {
         val ident = jump.identifier
         if(ident!=null) {
             val targetStatement = checkFunctionOrLabelExists(ident, jump)
             if(targetStatement!=null) {
-                if(targetStatement is BuiltinFunctionStatementPlaceholder)
+                if(targetStatement is BuiltinFunctionPlaceholder)
                     errors.err("can't jump to a builtin function", jump.position)
             }
+            if(targetStatement is Subroutine && targetStatement.parameters.any()) {
+                errors.err("can't jump to a subroutine that takes parameters", jump.position)
+            }
         }
 
         val addr = jump.address
-        if(addr!=null && (addr < 0 || addr > 65535))
+        if(addr!=null && addr > 65535u)
             errors.err("jump address must be valid integer 0..\$ffff", jump.position)
         super.visit(jump)
     }
 
+    override fun visit(gosub: GoSub) {
+        val ident = gosub.identifier
+        if(ident!=null) {
+            val targetStatement = checkFunctionOrLabelExists(ident, gosub)
+            if(targetStatement!=null) {
+                if(targetStatement is BuiltinFunctionPlaceholder)
+                    errors.err("can't gosub to a builtin function", gosub.position)
+            }
+        }
+
+        val addr = gosub.address
+        if(addr!=null && addr > 65535u)
+            errors.err("gosub address must be valid integer 0..\$ffff", gosub.position)
+        super.visit(gosub)
+    }
+
     override fun visit(block: Block) {
         val addr = block.address
-        if(addr!=null && (addr<0 || addr>65535)) {
+        if(addr!=null && addr>65535u) {
             errors.err("block memory address must be valid integer 0..\$ffff", block.position)
         }
 
@@ -196,8 +205,12 @@ internal class AstChecker(private val program: Program,
                 is Label,
                 is VarDecl,
                 is InlineAssembly,
-                is INameScope,
-                is NopStatement -> true
+                is IStatementContainer,
+                is Nop -> true
+                is Assignment -> {
+                    val target = statement.target.identifier!!.targetStatement(program)
+                    target === statement.previousSibling()      // an initializer assignment is okay
+                }
                 else -> false
             }
             if (!ok) {
@@ -217,7 +230,7 @@ internal class AstChecker(private val program: Program,
         super.visit(label)
     }
 
-    private fun hasReturnOrJump(scope: INameScope): Boolean {
+    private fun hasReturnOrJumpOrRts(scope: IStatementContainer): Boolean {
         class Searcher: IAstVisitor
         {
             var count=0
@@ -228,6 +241,13 @@ internal class AstChecker(private val program: Program,
             override fun visit(jump: Jump) {
                 count++
             }
+
+            override fun visit(inlineAssembly: InlineAssembly) {
+                val assembly = inlineAssembly.assembly
+                if(" rti" in assembly || "\trti" in assembly || " rts" in assembly || "\trts" in assembly ||
+                    " jmp" in assembly || "\tjmp" in assembly || " bra" in assembly || "\tbra" in assembly )
+                    count++
+            }
         }
 
         val s=Searcher()
@@ -245,8 +265,8 @@ internal class AstChecker(private val program: Program,
         if(subroutine.name in BuiltinFunctions)
             err("cannot redefine a built-in function")
 
-        if(subroutine.parameters.size>16)
-            err("subroutines are limited to 16 parameters")
+        if(subroutine.parameters.size>6 && !subroutine.isAsmSubroutine)
+            errors.warn("subroutine has a large number of parameters, this slows down code execution a lot", subroutine.position)
 
         val uniqueNames = subroutine.parameters.asSequence().map { it.name }.toSet()
         if(uniqueNames.size!=subroutine.parameters.size)
@@ -261,13 +281,11 @@ internal class AstChecker(private val program: Program,
 
         // subroutine must contain at least one 'return' or 'goto'
         // (or if it has an asm block, that must contain a 'rts' or 'jmp' or 'bra')
-        if(!hasReturnOrJump(subroutine)) {
-            if (subroutine.amountOfRtsInAsm() == 0) {
-                if (subroutine.returntypes.isNotEmpty()) {
-                    // for asm subroutines with an address, no statement check is possible.
-                    if (subroutine.asmAddress == null && !subroutine.inline)
-                        err("non-inline subroutine has result value(s) and thus must have at least one 'return' or 'goto' in it (or rts/jmp/bra in case of %asm)")
-                }
+        if(!hasReturnOrJumpOrRts(subroutine)) {
+            if (subroutine.returntypes.isNotEmpty()) {
+                // for asm subroutines with an address, no statement check is possible.
+                if (subroutine.asmAddress == null && !subroutine.inline)
+                    err("non-inline subroutine has result value(s) and thus must have at least one 'return' or 'goto' in it (or rts/jmp/bra in case of %asm)")
             }
         }
 
@@ -290,7 +308,7 @@ internal class AstChecker(private val program: Program,
                 else if(param.second.registerOrPair in arrayOf(RegisterOrPair.AX, RegisterOrPair.AY, RegisterOrPair.XY)) {
                     if (param.first.type != DataType.UWORD && param.first.type != DataType.WORD
                             && param.first.type != DataType.STR && param.first.type !in ArrayDatatypes && param.first.type != DataType.FLOAT)
-                        err("parameter '${param.first.name}' should be (u)word/address")
+                        err("parameter '${param.first.name}' should be (u)word (an address) or str")
                 }
                 else if(param.second.statusflag!=null) {
                     if (param.first.type != DataType.UBYTE)
@@ -381,11 +399,13 @@ internal class AstChecker(private val program: Program,
             if(statusFlagsNoCarry.isNotEmpty())
                 err("can only use Carry as status flag parameter")
 
-        } else {
-            // Pass-by-reference datatypes can not occur as parameters to a subroutine directly
-            // Instead, their reference (address) should be passed (as an UWORD).
-            if(subroutine.parameters.any{it.type in PassByReferenceDatatypes }) {
-                err("Pass-by-reference types (str, array) cannot occur as a parameter type directly. Instead, use an uword to receive their address, or access the variable from the outer scope directly.")
+        }
+
+        // Non-string and non-ubytearray Pass-by-reference datatypes can not occur as parameters to a subroutine directly
+        // Instead, their reference (address) should be passed (as an UWORD).
+        for(p in subroutine.parameters) {
+            if(p.type in PassByReferenceDatatypes && p.type !in listOf(DataType.STR, DataType.ARRAY_UB)) {
+                errors.err("this pass-by-reference type can't be used as a parameter type. Instead, use an uword to receive the address, or access the variable from the outer scope directly.", p.position)
             }
         }
     }
@@ -410,26 +430,20 @@ internal class AstChecker(private val program: Program,
     }
 
     override fun visit(assignment: Assignment) {
-        if(assignment.value is FunctionCall) {
-            val stmt = (assignment.value as FunctionCall).target.targetStatement(program)
-            if (stmt is Subroutine) {
-                val idt = assignment.target.inferType(program)
-                if(!idt.isKnown) {
-                     errors.err("return type mismatch", assignment.value.position)
-                }
-                if(stmt.returntypes.isEmpty() || (stmt.returntypes.size == 1 && stmt.returntypes.single() isNotAssignableTo idt.getOr(DataType.BYTE))) {
-                    errors.err("return type mismatch", assignment.value.position)
-                }
-            }
-        }
-
         val targetDt = assignment.target.inferType(program)
         val valueDt = assignment.value.inferType(program)
         if(valueDt.isKnown && !(valueDt isAssignableTo targetDt)) {
             if(targetDt.isIterable)
                 errors.err("cannot assign value to string or array", assignment.value.position)
-            else if(!(valueDt istype DataType.STR && targetDt istype DataType.UWORD))
-                errors.err("type of value doesn't match target", assignment.value.position)
+            else if(!(valueDt istype DataType.STR && targetDt istype DataType.UWORD)) {
+                if(targetDt.isUnknown) {
+                    if(assignment.target.identifier?.targetStatement(program)!=null)
+                        errors.err("target datatype is unknown", assignment.target.position)
+                    // otherwise, another error about missing symbol is already reported.
+                } else {
+                    errors.err("type of value $valueDt doesn't match target $targetDt", assignment.value.position)
+                }
+            }
         }
 
         if(assignment.value is TypecastExpression) {
@@ -437,6 +451,10 @@ internal class AstChecker(private val program: Program,
                 errors.err("typecasting a float value in-place makes no sense", assignment.value.position)
         }
 
+        val numvalue = assignment.value.constValue(program)
+        if(numvalue!=null && targetDt.isKnown)
+            checkValueTypeAndRange(targetDt.getOr(DataType.UNDEFINED), numvalue)
+
         super.visit(assignment)
     }
 
@@ -453,7 +471,7 @@ internal class AstChecker(private val program: Program,
         val targetIdentifier = assignTarget.identifier
         if (targetIdentifier != null) {
             val targetName = targetIdentifier.nameInSource
-            when (val targetSymbol = program.namespace.lookup(targetName, assignment)) {
+            when (val targetSymbol = assignment.definingScope.lookup(targetName)) {
                 null -> {
                     errors.err("undefined symbol: ${targetIdentifier.nameInSource.joinToString(".")}", targetIdentifier.position)
                     return
@@ -471,26 +489,18 @@ internal class AstChecker(private val program: Program,
             }
         }
 
-// target type check is already done at the Assignment:
-//        val targetDt = assignTarget.inferType(program, assignment).typeOrElse(DataType.STR)
-//        if(targetDt in IterableDatatypes)
-//            errors.err("cannot assign to a string or array type", assignTarget.position)
-
         if (assignment is Assignment) {
-
             val targetDatatype = assignTarget.inferType(program)
             if (targetDatatype.isKnown) {
                 val constVal = assignment.value.constValue(program)
-                if (constVal != null) {
-                    checkValueTypeAndRange(targetDatatype.getOr(DataType.BYTE), constVal)
-                } else {
+                if(constVal==null) {
                     val sourceDatatype = assignment.value.inferType(program)
                     if (sourceDatatype.isUnknown) {
-                        if (assignment.value !is FunctionCall)
-                            errors.err("assignment value is invalid or has no proper datatype", assignment.value.position)
+                        if (assignment.value !is FunctionCallExpression)
+                            errors.err("assignment value is invalid or has no proper datatype, maybe forgot '&' (address-of)", assignment.value.position)
                     } else {
-                        checkAssignmentCompatible(targetDatatype.getOr(DataType.BYTE), assignTarget,
-                                sourceDatatype.getOr(DataType.BYTE), assignment.value, assignment.position)
+                        checkAssignmentCompatible(targetDatatype.getOr(DataType.BYTE),
+                                sourceDatatype.getOr(DataType.BYTE), assignment.value)
                     }
                 }
             }
@@ -505,10 +515,10 @@ internal class AstChecker(private val program: Program,
     }
 
     override fun visit(decl: VarDecl) {
-        fun err(msg: String, position: Position?=null) = errors.err(msg, position ?: decl.position)
+        fun err(msg: String) = errors.err(msg, decl.position)
 
         // the initializer value can't refer to the variable itself (recursive definition)
-        if(decl.value?.referencesIdentifier(decl.name) == true || decl.arraysize?.indexExpr?.referencesIdentifier(decl.name) == true)
+        if(decl.value?.referencesIdentifier(listOf(decl.name)) == true || decl.arraysize?.indexExpr?.referencesIdentifier(listOf(decl.name)) == true)
             err("recursive var declaration")
 
         // CONST can only occur on simple types (byte, word, float)
@@ -521,9 +531,6 @@ internal class AstChecker(private val program: Program,
         if(!compilerOptions.floats && decl.datatype.oneOf(DataType.FLOAT, DataType.ARRAY_F) && decl.type!= VarDeclType.MEMORY)
             err("floating point used, but that is not enabled via options")
 
-        if(decl.datatype == DataType.FLOAT && (decl.zeropage==ZeropageWish.REQUIRE_ZEROPAGE || decl.zeropage==ZeropageWish.PREFER_ZEROPAGE))
-            errors.warn("floating point values won't be placed in Zeropage due to size constraints", decl.position)
-
         // ARRAY without size specifier MUST have an iterable initializer value
         if(decl.isArray && decl.arraysize==null) {
             if(decl.type== VarDeclType.MEMORY)
@@ -536,7 +543,7 @@ internal class AstChecker(private val program: Program,
                 err("unsized array declaration cannot use a single literal initialization value")
                 return
             }
-            if(decl.value is RangeExpr)
+            if(decl.value is RangeExpression)
                 throw FatalAstException("range expressions in vardecls should have been converted into array values during constFolding  $decl")
         }
 
@@ -546,7 +553,7 @@ internal class AstChecker(private val program: Program,
                     null -> {
                         // a vardecl without an initial value, don't bother with it
                     }
-                    is RangeExpr -> throw FatalAstException("range expression should have been converted to a true array value")
+                    is RangeExpression -> throw FatalAstException("range expression should have been converted to a true array value")
                     is StringLiteralValue -> {
                         checkValueTypeAndRangeString(decl.datatype, decl.value as StringLiteralValue)
                     }
@@ -586,10 +593,10 @@ internal class AstChecker(private val program: Program,
                 val numvalue = decl.value as? NumericLiteralValue
                 if(numvalue!=null) {
                     if (numvalue.type !in IntegerDatatypes || numvalue.number.toInt() < 0 || numvalue.number.toInt() > 65535) {
-                        err("memory address must be valid integer 0..\$ffff", decl.value?.position)
+                        err("memory address must be valid integer 0..\$ffff")
                     }
                 } else {
-                    err("value of memory mapped variable can only be a fixed number, perhaps you meant to use an address pointer type instead?", decl.value?.position)
+                    err("value of memory mapped variable can only be a fixed number, perhaps you meant to use an address pointer type instead?")
                 }
             }
         }
@@ -597,7 +604,7 @@ internal class AstChecker(private val program: Program,
         val declValue = decl.value
         if(declValue!=null && decl.type==VarDeclType.VAR) {
             if (declValue.inferType(program) isnot decl.datatype) {
-                err("initialisation value has incompatible type (${declValue.inferType(program)}) for the variable (${decl.datatype})", declValue.position)
+                err("initialisation value has incompatible type (${declValue.inferType(program)}) for the variable (${decl.datatype})")
             }
         }
 
@@ -626,14 +633,18 @@ internal class AstChecker(private val program: Program,
             }
         }
 
-        // string assignment is not supported in a vard
         if(decl.datatype==DataType.STR) {
-            if(decl.value==null)
-                err("string var must be initialized with a string literal")
-            else if (decl.type==VarDeclType.VAR && decl.value !is StringLiteralValue)
-                err("string var can only be initialized with a string literal")
+            if(decl.value==null) {
+                // complain about uninitialized str, but only if it's a regular variable
+                val parameter = (decl.parent as? Subroutine)?.parameters?.singleOrNull{ it.name==decl.name }
+                if(parameter==null)
+                    err("string var must be initialized with a string literal")
+            }
         }
 
+        if(compilerOptions.zeropage==ZeropageType.DONTUSE && decl.zeropage==ZeropageWish.REQUIRE_ZEROPAGE)
+            err("zeropage usage has been disabled by options")
+
         super.visit(decl)
     }
 
@@ -670,6 +681,8 @@ internal class AstChecker(private val program: Program,
                     err("this directive may only occur at module level")
                 if(directive.args.size!=2 || directive.args[0].int==null || directive.args[1].int==null)
                     err("requires two addresses (start, end)")
+                if(directive.args[0].int!! > 255u || directive.args[1].int!! > 255u)
+                    err("start and end addresss must be in Zeropage so 0..255")
             }
             "%address" -> {
                 if(directive.parent !is Module)
@@ -703,7 +716,7 @@ internal class AstChecker(private val program: Program,
                     err("this directive can't be used here")
                 val errormsg = "invalid asmbinary directive, expected arguments: \"filename\" [, offset [, length ] ]"
                 if(directive.args.isEmpty()) err(errormsg)
-                else if(directive.args.isNotEmpty() && directive.args[0].str==null) err(errormsg)
+                else if(directive.args[0].str==null) err(errormsg)
                 else if(directive.args.size>=2 && directive.args[1].int==null) err(errormsg)
                 else if(directive.args.size==3 && directive.args[2].int==null) err(errormsg)
                 else if(directive.args.size>3) err(errormsg)
@@ -768,7 +781,7 @@ internal class AstChecker(private val program: Program,
 
     override fun visit(char: CharLiteral) {
         try {  // just *try* if it can be encoded, don't actually do it
-            compTarget.encodeString(char.value.toString(), char.altEncoding)
+            compilerOptions.compTarget.encodeString(char.value.toString(), char.encoding)
         } catch (cx: CharConversionException) {
             errors.err(cx.message ?: "can't encode character", char.position)
         }
@@ -780,7 +793,9 @@ internal class AstChecker(private val program: Program,
         checkValueTypeAndRangeString(DataType.STR, string)
 
         try {  // just *try* if it can be encoded, don't actually do it
-            compTarget.encodeString(string.value, string.altEncoding)
+            val bytes = compilerOptions.compTarget.encodeString(string.value, string.encoding)
+            if(0u in bytes)
+                errors.warn("a character in the string encodes into the 0-byte, which will terminate the string prematurely", string.position)
         } catch (cx: CharConversionException) {
             errors.err(cx.message ?: "can't encode string", string.position)
         }
@@ -789,11 +804,10 @@ internal class AstChecker(private val program: Program,
     }
 
     override fun visit(expr: PrefixExpression) {
-        val idt = expr.inferType(program)
-        if(!idt.isKnown)
+        val dt = expr.expression.inferType(program).getOr(DataType.UNDEFINED)
+        if(dt==DataType.UNDEFINED)
             return  // any error should be reported elsewhere
 
-        val dt = idt.getOr(DataType.UNDEFINED)
         if(expr.operator=="-") {
             if (dt != DataType.BYTE && dt != DataType.WORD && dt != DataType.FLOAT) {
                 errors.err("can only take negative of a signed number type", expr.position)
@@ -824,7 +838,7 @@ internal class AstChecker(private val program: Program,
         when(expr.operator){
             "/", "%" -> {
                 val constvalRight = expr.right.constValue(program)
-                val divisor = constvalRight?.number?.toDouble()
+                val divisor = constvalRight?.number
                 if(divisor==0.0)
                     errors.err("division by zero", expr.right.position)
                 if(expr.operator=="%") {
@@ -850,14 +864,30 @@ internal class AstChecker(private val program: Program,
                 if(leftDt !in IntegerDatatypes || rightDt !in IntegerDatatypes)
                     errors.err("bitwise operator can only be used on integer operands", expr.right.position)
             }
+            "in" -> throw FatalAstException("in expression should have been replaced by containmentcheck")
         }
 
         if(leftDt !in NumericDatatypes && leftDt != DataType.STR)
             errors.err("left operand is not numeric or str", expr.left.position)
         if(rightDt!in NumericDatatypes && rightDt != DataType.STR)
             errors.err("right operand is not numeric or str", expr.right.position)
-        if(leftDt!=rightDt)
-            errors.err("left and right operands aren't the same type", expr.left.position)
+        if(leftDt!=rightDt) {
+            if(leftDt==DataType.STR && rightDt in IntegerDatatypes) {
+                // only exception allowed: str * constvalue
+                if(expr.right.constValue(program)!=null)
+                    errors.err("can only use string repeat with a constant number value", expr.left.position)
+            } else {
+                errors.err("left and right operands aren't the same type", expr.left.position)
+            }
+        }
+
+        if(expr.operator !in ComparisonOperators) {
+            if (leftDt == DataType.STR && rightDt == DataType.STR || leftDt in ArrayDatatypes && rightDt in ArrayDatatypes) {
+                // str+str  and  str*number have already been const evaluated before we get here.
+                errors.err("no computational expressions with strings or arrays are possible", expr.position)
+            }
+        }
+
     }
 
     override fun visit(typecast: TypecastExpression) {
@@ -867,10 +897,13 @@ internal class AstChecker(private val program: Program,
         if(!typecast.expression.inferType(program).isKnown)
             errors.err("this expression doesn't return a value", typecast.expression.position)
 
+        if(typecast.expression is NumericLiteralValue)
+            errors.err("can't cast the value to the requested target type", typecast.expression.position)
+
         super.visit(typecast)
     }
 
-    override fun visit(range: RangeExpr) {
+    override fun visit(range: RangeExpression) {
         fun err(msg: String) {
             errors.err(msg, range.position)
         }
@@ -903,28 +936,28 @@ internal class AstChecker(private val program: Program,
         }
     }
 
-    override fun visit(functionCall: FunctionCall) {
+    override fun visit(functionCallExpr: FunctionCallExpression) {
         // this function call is (part of) an expression, which should be in a statement somewhere.
-        val stmtOfExpression = findParentNode<Statement>(functionCall)
-                ?: throw FatalAstException("cannot determine statement scope of function call expression at ${functionCall.position}")
+        val stmtOfExpression = findParentNode<Statement>(functionCallExpr)
+                ?: throw FatalAstException("cannot determine statement scope of function call expression at ${functionCallExpr.position}")
 
-        val targetStatement = checkFunctionOrLabelExists(functionCall.target, stmtOfExpression)
+        val targetStatement = checkFunctionOrLabelExists(functionCallExpr.target, stmtOfExpression)
         if(targetStatement!=null)
-            checkFunctionCall(targetStatement, functionCall.args, functionCall.position)
+            checkFunctionCall(targetStatement, functionCallExpr.args, functionCallExpr.position)
 
         // warn about sgn(unsigned) this is likely a mistake
-        if(functionCall.target.nameInSource.last()=="sgn") {
-            val sgnArgType = functionCall.args.first().inferType(program)
+        if(functionCallExpr.target.nameInSource.last()=="sgn") {
+            val sgnArgType = functionCallExpr.args.first().inferType(program)
             if(sgnArgType istype DataType.UBYTE  || sgnArgType istype DataType.UWORD)
-                errors.warn("sgn() of unsigned type is always 0 or 1, this is perhaps not what was intended", functionCall.args.first().position)
+                errors.warn("sgn() of unsigned type is always 0 or 1, this is perhaps not what was intended", functionCallExpr.args.first().position)
         }
 
-        val error = VerifyFunctionArgTypes.checkTypes(functionCall, program)
+        val error = VerifyFunctionArgTypes.checkTypes(functionCallExpr, program)
         if(error!=null)
-            errors.err(error, functionCall.position)
+            errors.err(error, functionCallExpr.position)
 
         // check the functions that return multiple returnvalues.
-        val stmt = functionCall.target.targetStatement(program)
+        val stmt = functionCallExpr.target.targetStatement(program)
         if (stmt is Subroutine) {
             if (stmt.returntypes.size > 1) {
                 // Currently, it's only possible to handle ONE (or zero) return values from a subroutine.
@@ -935,12 +968,9 @@ internal class AstChecker(private val program: Program,
                 // if the asmsub returns multiple values and one of them is via a status register bit,
                 // it *is* possible to handle them by just actually assigning the register value and
                 // dealing with the status bit as just being that, the status bit after the call.
-                val (returnRegisters, returnStatusflags) = stmt.asmReturnvaluesRegisters.partition { rr -> rr.registerOrPair != null }
-                if (returnRegisters.isEmpty() || returnRegisters.size == 1) {
-                    if (returnStatusflags.any())
-                        errors.warn("this asmsub also has one or more return 'values' in one of the status flags", functionCall.position)
-                } else {
-                    errors.err("It's not possible to store the multiple result values of this asmsub call; you should use a small block of custom inline assembly for this.", functionCall.position)
+                val (returnRegisters, _) = stmt.asmReturnvaluesRegisters.partition { rr -> rr.registerOrPair != null }
+                if (returnRegisters.size>1) {
+                    errors.err("It's not possible to store the multiple result values of this asmsub call; you should use a small block of custom inline assembly for this.", functionCallExpr.position)
                 }
             }
         }
@@ -948,56 +978,62 @@ internal class AstChecker(private val program: Program,
         // functions that don't return a value, can't be used in an expression or assignment
         if(targetStatement is Subroutine) {
             if(targetStatement.returntypes.isEmpty()) {
-                if(functionCall.parent is Expression || functionCall.parent is Assignment)
-                    errors.err("subroutine doesn't return a value", functionCall.position)
+                if(functionCallExpr.parent is Expression || functionCallExpr.parent is Assignment)
+                    errors.err("subroutine doesn't return a value", functionCallExpr.position)
             }
         }
-        else if(targetStatement is BuiltinFunctionStatementPlaceholder) {
-            if(builtinFunctionReturnType(targetStatement.name, functionCall.args, program).isUnknown) {
-                if(functionCall.parent is Expression || functionCall.parent is Assignment)
-                    errors.err("function doesn't return a value", functionCall.position)
+        else if(targetStatement is BuiltinFunctionPlaceholder) {
+            if(builtinFunctionReturnType(targetStatement.name, functionCallExpr.args, program).isUnknown) {
+                if(functionCallExpr.parent is Expression || functionCallExpr.parent is Assignment)
+                    errors.err("function doesn't return a value", functionCallExpr.position)
             }
         }
 
-        super.visit(functionCall)
+        super.visit(functionCallExpr)
     }
 
     override fun visit(functionCallStatement: FunctionCallStatement) {
         val targetStatement = checkFunctionOrLabelExists(functionCallStatement.target, functionCallStatement)
-        if(targetStatement!=null)
+        if(targetStatement!=null) {
             checkFunctionCall(targetStatement, functionCallStatement.args, functionCallStatement.position)
-        if (!functionCallStatement.void) {
-            // check for unused return values
-            if (targetStatement is Subroutine && targetStatement.returntypes.isNotEmpty()) {
-                if(targetStatement.returntypes.size==1)
-                    errors.warn("result value of subroutine call is discarded (use void?)", functionCallStatement.position)
-                else
-                    errors.warn("result values of subroutine call are discarded (use void?)", functionCallStatement.position)
-            }
-            else if(targetStatement is BuiltinFunctionStatementPlaceholder) {
-                val rt = builtinFunctionReturnType(targetStatement.name, functionCallStatement.args, program)
-                if(rt.isKnown)
-                    errors.warn("result value of a function call is discarded (use void?)", functionCallStatement.position)
-            }
+            checkUnusedReturnValues(functionCallStatement, targetStatement, program, errors)
         }
 
-        if(functionCallStatement.target.nameInSource.last() == "sort") {
-            // sort is not supported on float arrays
-            val idref = functionCallStatement.args.singleOrNull() as? IdentifierReference
-            if(idref!=null && idref.inferType(program) istype DataType.ARRAY_F) {
-                errors.err("sorting a floating point array is not supported", functionCallStatement.args.first().position)
+        val funcName = functionCallStatement.target.nameInSource
+
+        if(funcName.size==1) {
+            // check some builtin function calls
+            if(funcName[0] == "sort") {
+                // sort is not supported on float arrays
+                val idref = functionCallStatement.args.singleOrNull() as? IdentifierReference
+                if(idref!=null && idref.inferType(program) istype DataType.ARRAY_F) {
+                    errors.err("sorting a floating point array is not supported", functionCallStatement.args.first().position)
+                }
             }
+            else if(funcName[0] in arrayOf("pop", "popw")) {
+                // can only pop into a variable, that has to have the correct type
+                val idref = functionCallStatement.args[0]
+                if(idref !is IdentifierReference) {
+                    if(idref is TypecastExpression) {
+                        val passByRef = idref.expression.inferType(program).isPassByReference
+                        if(idref.type!=DataType.UWORD || !passByRef)
+                            errors.err("invalid argument to pop, must be a variable with the correct type: ${functionCallStatement.args.first()}", functionCallStatement.args.first().position)
+                    } else {
+                        errors.err("invalid argument to pop, must be a variable with the correct type: ${functionCallStatement.args.first()}", functionCallStatement.args.first().position)
+                    }
+                }
+            }
+
+            if(funcName[0] in arrayOf("rol", "ror", "rol2", "ror2", "swap", "sort", "reverse")) {
+                // in-place modification, can't be done on literals
+                if(functionCallStatement.args.any { it !is IdentifierReference && it !is ArrayIndexedExpression && it !is DirectMemoryRead }) {
+                    errors.err("invalid argument to a in-place modifying function", functionCallStatement.args.first().position)
+                }
+            }
+
         }
 
-        if(functionCallStatement.target.nameInSource.last() in arrayOf("rol", "ror", "rol2", "ror2", "swap", "sort", "reverse")) {
-            // in-place modification, can't be done on literals
-            if(functionCallStatement.args.any { it !is IdentifierReference && it !is ArrayIndexedExpression && it !is DirectMemoryRead }) {
-                errors.err("invalid argument to a in-place modifying function", functionCallStatement.args.first().position)
-            }
-        }
-
-        val error =
-            VerifyFunctionArgTypes.checkTypes(functionCallStatement, program)
+        val error = VerifyFunctionArgTypes.checkTypes(functionCallStatement, program)
         if(error!=null) {
             errors.err(error, functionCallStatement.args.firstOrNull()?.position ?: functionCallStatement.position)
         }
@@ -1009,7 +1045,7 @@ internal class AstChecker(private val program: Program,
         if(target is Label && args.isNotEmpty())
             errors.err("cannot use arguments when calling a label", position)
 
-        if(target is BuiltinFunctionStatementPlaceholder) {
+        if(target is BuiltinFunctionPlaceholder) {
             if(target.name=="swap") {
                 // swap() is a bit weird because this one is translated into an operations directly, instead of being a function call
                 val dt1 = args[0].inferType(program)
@@ -1045,13 +1081,16 @@ internal class AstChecker(private val program: Program,
                     var ident: IdentifierReference? = null
                     if(arg.value is IdentifierReference)
                         ident = arg.value as IdentifierReference
-                    else if(arg.value is FunctionCall) {
-                        val fcall = arg.value as FunctionCall
+                    else if(arg.value is FunctionCallExpression) {
+                        val fcall = arg.value as FunctionCallExpression
                         if(fcall.target.nameInSource == listOf("lsb") || fcall.target.nameInSource == listOf("msb"))
                             ident = fcall.args[0] as? IdentifierReference
                     }
                     if(ident!=null && ident.nameInSource[0] == "cx16" && ident.nameInSource[1].startsWith("r")) {
-                        val reg = RegisterOrPair.valueOf(ident.nameInSource[1].uppercase())
+                        var regname = ident.nameInSource[1].uppercase()
+                        if(regname.endsWith('L') || regname.endsWith('H') || regname.endsWith('s'))
+                            regname=regname.substring(0, regname.length-1)
+                        val reg = RegisterOrPair.valueOf(regname)
                         val same = params.filter { it.value.registerOrPair==reg }
                         for(s in same) {
                             if(s.index!=arg.index) {
@@ -1067,7 +1106,7 @@ internal class AstChecker(private val program: Program,
     override fun visit(postIncrDecr: PostIncrDecr) {
         if(postIncrDecr.target.identifier != null) {
             val targetName = postIncrDecr.target.identifier!!.nameInSource
-            val target = program.namespace.lookup(targetName, postIncrDecr)
+            val target = postIncrDecr.definingScope.lookup(targetName)
             if(target==null) {
                 val symbol = postIncrDecr.target.identifier!!
                 errors.err("undefined symbol: ${symbol.nameInSource.joinToString(".")}", symbol.position)
@@ -1124,11 +1163,11 @@ internal class AstChecker(private val program: Program,
         super.visit(arrayIndexedExpression)
     }
 
-    override fun visit(whenStatement: WhenStatement) {
-        if(!whenStatement.condition.inferType(program).isInteger)
-            errors.err("when condition must be an integer value", whenStatement.position)
+    override fun visit(whenStmt: When) {
+        if(!whenStmt.condition.inferType(program).isInteger)
+            errors.err("when condition must be an integer value", whenStmt.position)
         val tally = mutableSetOf<Int>()
-        for((choices, choiceNode) in whenStatement.choiceValues(program)) {
+        for((choices, choiceNode) in whenStmt.choiceValues(program)) {
             if(choices!=null) {
                 for (c in choices) {
                     if(c in tally)
@@ -1139,14 +1178,14 @@ internal class AstChecker(private val program: Program,
             }
         }
 
-        if(whenStatement.choices.isEmpty())
-            errors.err("empty when statement", whenStatement.position)
+        if(whenStmt.choices.isEmpty())
+            errors.err("empty when statement", whenStmt.position)
 
-        super.visit(whenStatement)
+        super.visit(whenStmt)
     }
 
     override fun visit(whenChoice: WhenChoice) {
-        val whenStmt = whenChoice.parent as WhenStatement
+        val whenStmt = whenChoice.parent as When
         if(whenChoice.values!=null) {
             val conditionType = whenStmt.condition.inferType(program)
             if(!conditionType.isKnown)
@@ -1166,23 +1205,149 @@ internal class AstChecker(private val program: Program,
         super.visit(whenChoice)
     }
 
+    override fun visit(containment: ContainmentCheck) {
+        val elementDt = containment.element.inferType(program)
+        val iterableDt = containment.iterable.inferType(program)
+
+        if(containment.parent is BinaryExpression)
+            errors.err("containment check is currently not supported in complex expressions", containment.position)
+
+        if(iterableDt.isIterable) {
+            val iterableEltDt = ArrayToElementTypes.getValue(iterableDt.getOr(DataType.UNDEFINED))
+            val invalidDt = if (elementDt.isBytes) {
+                iterableEltDt !in ByteDatatypes
+            } else if (elementDt.isWords) {
+                iterableEltDt !in WordDatatypes
+            } else {
+                false
+            }
+            if (invalidDt)
+                errors.err("element datatype doesn't match iterable datatype", containment.position)
+        } else {
+            errors.err("value set for containment check must be an iterable type", containment.iterable.position)
+        }
+
+        super.visit(containment)
+    }
+
+    override fun visit(pipe: PipeExpression) {
+        processPipe(pipe.expressions, pipe)
+        val last = pipe.expressions.last() as IdentifierReference
+        val target = last.targetStatement(program)!!
+        when(target) {
+            is BuiltinFunctionPlaceholder -> {
+                if(BuiltinFunctions.getValue(target.name).known_returntype==null)
+                    errors.err("invalid pipe expression; last term doesn't return a value", last.position)
+            }
+            is Subroutine -> {
+                if(target.returntypes.isEmpty())
+                    errors.err("invalid pipe expression; last term doesn't return a value", last.position)
+                else if(target.returntypes.size!=1)
+                    errors.err("invalid pipe expression; last term doesn't return a single value", last.position)
+            }
+            else -> errors.err("invalid pipe expression; last term doesn't return a value", last.position)
+        }
+        super.visit(pipe)
+    }
+
+    override fun visit(pipe: Pipe) {
+        processPipe(pipe.expressions, pipe)
+        super.visit(pipe)
+    }
+
+    private fun processPipe(expressions: List<Expression>, scope: Node) {
+        // first expression is just any expression producing a value
+        // all other expressions should be the name of a unary function that returns a single value
+        // the last expression should be the name of a unary function whose return value we don't care about.
+        if (expressions.size < 2) {
+            errors.err("pipe is missing one or more expressions", scope.position)
+        } else {
+            // invalid size and other issues will be handled by the ast checker later.
+            var valueDt = expressions[0].inferType(program).getOrElse {
+                throw FatalAstException("invalid dt ${expressions[0]} @ ${scope.position}")
+            }
+
+            for(expr in expressions.drop(1)) {         // just keep the first expression value as-is
+                val functionName = expr as? IdentifierReference
+                val function = functionName?.targetStatement(program)
+                if(functionName!=null && function!=null) {
+                    when (function) {
+                        is BuiltinFunctionPlaceholder -> {
+                            val func = BuiltinFunctions.getValue(function.name)
+                            if(func.parameters.size!=1)
+                                errors.err("can only use unary function", expr.position)
+                            else if(func.known_returntype==null && expr !== expressions.last())
+                                errors.err("function must return a single value", expr.position)
+
+                            val paramDts = func.parameters.firstOrNull()?.possibleDatatypes
+                            if(paramDts!=null && !paramDts.any { valueDt isAssignableTo it })
+                                errors.err("pipe value datatype $valueDt incompatible withfunction argument ${paramDts.toList()}", functionName.position)
+
+                            valueDt = func.known_returntype!!
+                        }
+                        is Subroutine -> {
+                            if(function.parameters.size!=1)
+                                errors.err("can only use unary function", expr.position)
+                            else if(function.returntypes.size!=1 && expr !== expressions.last())
+                                errors.err("function must return a single value", expr.position)
+
+                            val paramDt = function.parameters.firstOrNull()?.type
+                            if(paramDt!=null && !(valueDt isAssignableTo paramDt))
+                                errors.err("pipe value datatype $valueDt incompatible with function argument $paramDt", functionName.position)
+
+                            if(function.returntypes.isNotEmpty())
+                                valueDt = function.returntypes.single()
+                        }
+                        else -> {
+                            throw FatalAstException("weird function")
+                        }
+                    }
+                } else {
+                    if(expr is IFunctionCall)
+                        errors.err("use only the name of the function, not a call", expr.position)
+                    else
+                        errors.err("can only use unary function", expr.position)
+                }
+            }
+        }
+    }
+
     private fun checkFunctionOrLabelExists(target: IdentifierReference, statement: Statement): Statement? {
         when (val targetStatement = target.targetStatement(program)) {
-            is Label, is Subroutine, is BuiltinFunctionStatementPlaceholder -> return targetStatement
-            null -> errors.err("undefined function or subroutine: ${target.nameInSource.joinToString(".")}", statement.position)
-            else -> errors.err("cannot call that: ${target.nameInSource.joinToString(".")}", statement.position)
+            is Label, is Subroutine, is BuiltinFunctionPlaceholder -> return targetStatement
+            is VarDecl -> {
+                if(statement is Jump) {
+                    if (targetStatement.datatype == DataType.UWORD)
+                        return targetStatement
+                    else
+                        errors.err("wrong address variable datatype, expected uword", target.position)
+                }
+                else
+                    errors.err("cannot call that: ${target.nameInSource.joinToString(".")}", target.position)
+            }
+            null -> errors.err("undefined function or subroutine: ${target.nameInSource.joinToString(".")}", target.position)
+            else -> errors.err("cannot call that: ${target.nameInSource.joinToString(".")}", target.position)
         }
         return null
     }
 
     private fun checkValueTypeAndRangeString(targetDt: DataType, value: StringLiteralValue) : Boolean {
         return if (targetDt == DataType.STR) {
-            if (value.value.length > 255) {
-                errors.err("string length must be 0-255", value.position)
-                false
+            when {
+                value.value.length > 255 -> {
+                    errors.err("string length must be 0-255", value.position)
+                    false
+                }
+                value.value.isEmpty() -> {
+                    val decl = value.parent as? VarDecl
+                    if(decl!=null && (decl.zeropage==ZeropageWish.REQUIRE_ZEROPAGE || decl.zeropage==ZeropageWish.PREFER_ZEROPAGE)) {
+                        errors.err("string in Zeropage must be non-empty", value.position)
+                        false
+                    }
+                    else true
+                }
+                else -> true
             }
-            else
-                true
         }
         else false
     }
@@ -1206,7 +1371,7 @@ internal class AstChecker(private val program: Program,
                     val arraySpecSize = arrayspec.constIndex()
                     val arraySize = value.value.size
                     if(arraySpecSize!=null && arraySpecSize>0) {
-                        if(arraySpecSize<1 || arraySpecSize>256)
+                        if(arraySpecSize>256)
                             return err("byte array length must be 1-256")
                         val expectedSize = arrayspec.constIndex() ?: return err("array size specifier must be constant integer value")
                         if (arraySize != expectedSize)
@@ -1225,7 +1390,7 @@ internal class AstChecker(private val program: Program,
                     val arraySpecSize = arrayspec.constIndex()
                     val arraySize = value.value.size
                     if(arraySpecSize!=null && arraySpecSize>0) {
-                        if(arraySpecSize<1 || arraySpecSize>128)
+                        if(arraySpecSize>128)
                             return err("word array length must be 1-128")
                         val expectedSize = arrayspec.constIndex() ?: return err("array size specifier must be constant integer value")
                         if (arraySize != expectedSize)
@@ -1244,7 +1409,7 @@ internal class AstChecker(private val program: Program,
                     val arraySize = value.value.size
                     val arraySpecSize = arrayspec.constIndex()
                     if(arraySpecSize!=null && arraySpecSize>0) {
-                        if(arraySpecSize < 1 || arraySpecSize>51)
+                        if(arraySpecSize>51)
                             return err("float array length must be 1-51")
                         val expectedSize = arrayspec.constIndex() ?: return err("array size specifier must be constant integer value")
                         if (arraySize != expectedSize)
@@ -1254,7 +1419,7 @@ internal class AstChecker(private val program: Program,
 
                     // check if the floating point values are all within range
                     val doubles = value.value.map {it.constValue(program)?.number!!.toDouble()}.toDoubleArray()
-                    if(doubles.any { it < compTarget.machine.FLOAT_MAX_NEGATIVE || it > compTarget.machine.FLOAT_MAX_POSITIVE })
+                    if(doubles.any { it < compilerOptions.compTarget.machine.FLOAT_MAX_NEGATIVE || it > compilerOptions.compTarget.machine.FLOAT_MAX_POSITIVE })
                         return err("floating point value overflow")
                     return true
                 }
@@ -1271,7 +1436,7 @@ internal class AstChecker(private val program: Program,
         }
         when (targetDt) {
             DataType.FLOAT -> {
-                val number=value.number.toDouble()
+                val number=value.number
                 if (number > 1.7014118345e+38 || number < -1.7014118345e+38)
                     return err("value '$number' out of range for MFLPT format")
             }
@@ -1347,12 +1512,11 @@ internal class AstChecker(private val program: Program,
     }
 
     private fun checkAssignmentCompatible(targetDatatype: DataType,
-                                          target: AssignTarget,
                                           sourceDatatype: DataType,
-                                          sourceValue: Expression,
-                                          position: Position) : Boolean {
+                                          sourceValue: Expression) : Boolean {
+        val position = sourceValue.position
 
-        if(sourceValue is RangeExpr)
+        if(sourceValue is RangeExpression)
             errors.err("can't assign a range value to something else", position)
 
         val result =  when(targetDatatype) {
@@ -1378,15 +1542,25 @@ internal class AstChecker(private val program: Program,
             errors.err("cannot assign float to ${targetDatatype.name.lowercase()}; possible loss of precision. Suggestion: round the value or revert to integer arithmetic", position)
         else {
             if(targetDatatype!=DataType.UWORD && sourceDatatype !in PassByReferenceDatatypes)
-                errors.err(
-                    "cannot assign ${sourceDatatype.name.lowercase()} to ${
-                        targetDatatype.name.lowercase(
-                            Locale.getDefault()
-                        )
-                    }", position)
+                errors.err("type of value $sourceDatatype doesn't match target $targetDatatype", position)
         }
 
-
         return false
     }
 }
+
+internal fun checkUnusedReturnValues(call: FunctionCallStatement, target: Statement, program: Program, errors: IErrorReporter) {
+    if (!call.void) {
+        // check for unused return values
+        if (target is Subroutine && target.returntypes.isNotEmpty()) {
+            if (target.returntypes.size == 1)
+                errors.warn("result value of subroutine call is discarded (use void?)", call.position)
+            else
+                errors.warn("result values of subroutine call are discarded (use void?)", call.position)
+        } else if (target is BuiltinFunctionPlaceholder) {
+            val rt = builtinFunctionReturnType(target.name, call.args, program)
+            if (rt.isKnown)
+                errors.warn("result value of a function call is discarded (use void?)", call.position)
+        }
+    }
+}

compiler/src/prog8/compiler/astprocessing/AstExtensions.kt

@@ -3,82 +3,40 @@ package prog8.compiler.astprocessing
 import prog8.ast.Node
 import prog8.ast.Program
 import prog8.ast.base.DataType
-import prog8.ast.base.VarDeclType
-import prog8.ast.expressions.*
-import prog8.ast.statements.AssignTarget
+import prog8.ast.expressions.CharLiteral
+import prog8.ast.expressions.IdentifierReference
+import prog8.ast.expressions.NumericLiteralValue
 import prog8.ast.statements.Directive
+import prog8.ast.statements.VarDeclOrigin
 import prog8.ast.walk.AstWalker
 import prog8.ast.walk.IAstModification
-import prog8.compiler.BeforeAsmGenerationAstChanger
-import prog8.compiler.CompilationOptions
-import prog8.compiler.IErrorReporter
-import prog8.compiler.IStringEncoding
-import prog8.compiler.target.ICompilationTarget
-import prog8.compiler.target.IMachineDefinition
-import kotlin.math.abs
+import prog8.compilerinterface.CompilationOptions
+import prog8.compilerinterface.IErrorReporter
+import prog8.compilerinterface.IStringEncoding
 
 
-fun RangeExpr.size(encoding: IStringEncoding): Int? {
-    val fromLv = (from as? NumericLiteralValue)
-    val toLv = (to as? NumericLiteralValue)
-    if(fromLv==null || toLv==null)
-        return null
-    return toConstantIntegerRange(encoding)?.count()
-}
-
-fun RangeExpr.toConstantIntegerRange(encoding: IStringEncoding): IntProgression? {
-    val fromVal: Int
-    val toVal: Int
-    val fromString = from as? StringLiteralValue
-    val toString = to as? StringLiteralValue
-    if(fromString!=null && toString!=null ) {
-        // string range -> int range over character values
-        fromVal = encoding.encodeString(fromString.value, fromString.altEncoding)[0].toInt()
-        toVal = encoding.encodeString(toString.value, fromString.altEncoding)[0].toInt()
-    } else {
-        val fromLv = from as? NumericLiteralValue
-        val toLv = to as? NumericLiteralValue
-        if(fromLv==null || toLv==null)
-            return null         // non-constant range
-        // integer range
-        fromVal = fromLv.number.toInt()
-        toVal = toLv.number.toInt()
-    }
-    val stepVal = (step as? NumericLiteralValue)?.number?.toInt() ?: 1
-    return makeRange(fromVal, toVal, stepVal)
-}
-
-private fun makeRange(fromVal: Int, toVal: Int, stepVal: Int): IntProgression {
-    return when {
-        fromVal <= toVal -> when {
-            stepVal <= 0 -> IntRange.EMPTY
-            stepVal == 1 -> fromVal..toVal
-            else -> fromVal..toVal step stepVal
-        }
-        else -> when {
-            stepVal >= 0 -> IntRange.EMPTY
-            stepVal == -1 -> fromVal downTo toVal
-            else -> fromVal downTo toVal step abs(stepVal)
-        }
-    }
-}
-
-
-internal fun Program.checkValid(compilerOptions: CompilationOptions, errors: IErrorReporter, compTarget: ICompilationTarget) {
-    val checker = AstChecker(this, compilerOptions, errors, compTarget)
+internal fun Program.checkValid(errors: IErrorReporter, compilerOptions: CompilationOptions) {
+    val parentChecker = ParentNodeChecker()
+    parentChecker.visit(this)
+    val checker = AstChecker(this, errors, compilerOptions)
     checker.visit(this)
 }
 
-internal fun Program.processAstBeforeAsmGeneration(errors: IErrorReporter, compTarget: ICompilationTarget) {
-    val fixer = BeforeAsmGenerationAstChanger(this, errors, compTarget)
+internal fun Program.processAstBeforeAsmGeneration(compilerOptions: CompilationOptions, errors: IErrorReporter) {
+    val fixer = BeforeAsmAstChanger(this, compilerOptions, errors)
     fixer.visit(this)
     while(errors.noErrors() && fixer.applyModifications()>0) {
         fixer.visit(this)
     }
+    val cleaner = BeforeAsmTypecastCleaner(this, errors)
+    cleaner.visit(this)
+    while(errors.noErrors() && cleaner.applyModifications()>0) {
+        cleaner.visit(this)
+    }
 }
 
-internal fun Program.reorderStatements(errors: IErrorReporter) {
-    val reorder = StatementReorderer(this, errors)
+internal fun Program.reorderStatements(errors: IErrorReporter, options: CompilationOptions) {
+    val reorder = StatementReorderer(this, errors, options)
     reorder.visit(this)
     if(errors.noErrors()) {
         reorder.applyModifications()
@@ -88,12 +46,12 @@ internal fun Program.reorderStatements(errors: IErrorReporter) {
     }
 }
 
-internal fun Program.charLiteralsToUByteLiterals(errors: IErrorReporter, enc: IStringEncoding) {
+internal fun Program.charLiteralsToUByteLiterals(enc: IStringEncoding) {
     val walker = object : AstWalker() {
         override fun after(char: CharLiteral, parent: Node): Iterable<IAstModification> {
             return listOf(IAstModification.ReplaceNode(
                 char,
-                NumericLiteralValue(DataType.UBYTE, enc.encodeString(char.value.toString(), char.altEncoding)[0].toInt(), char.position),
+                NumericLiteralValue(DataType.UBYTE, enc.encodeString(char.value.toString(), char.encoding)[0].toDouble(), char.position),
                 parent
             ))
         }
@@ -102,20 +60,34 @@ internal fun Program.charLiteralsToUByteLiterals(errors: IErrorReporter, enc: IS
     walker.applyModifications()
 }
 
-internal fun Program.addTypecasts(errors: IErrorReporter) {
-    val caster = TypecastsAdder(this, errors)
+internal fun Program.addTypecasts(errors: IErrorReporter, options: CompilationOptions) {
+    val caster = TypecastsAdder(this, options, errors)
     caster.visit(this)
     caster.applyModifications()
 }
 
+fun Program.desugaring(errors: IErrorReporter): Int {
+    val desugar = CodeDesugarer(this, errors)
+    desugar.visit(this)
+    return desugar.applyModifications()
+}
+
 internal fun Program.verifyFunctionArgTypes() {
     val fixer = VerifyFunctionArgTypes(this)
     fixer.visit(this)
 }
 
+internal fun Program.preprocessAst(errors: IErrorReporter) {
+    val transforms = AstPreprocessor(this, errors)
+    transforms.visit(this)
+    var mods = transforms.applyModifications()
+    while(mods>0)
+        mods = transforms.applyModifications()
+}
+
 internal fun Program.checkIdentifiers(errors: IErrorReporter, options: CompilationOptions) {
 
-    val checker2 = AstIdentifiersChecker(this, errors, options.compTarget)
+    val checker2 = AstIdentifiersChecker(errors, this, options.compTarget)
     checker2.visit(this)
 
     if(errors.noErrors()) {
@@ -124,18 +96,18 @@ internal fun Program.checkIdentifiers(errors: IErrorReporter, options: Compilati
         transforms.applyModifications()
         val lit2decl = LiteralsToAutoVars(this)
         lit2decl.visit(this)
-        lit2decl.applyModifications()
+        if(errors.noErrors())
+            lit2decl.applyModifications()
     }
 }
 
-internal fun Program.variousCleanups(program: Program, errors: IErrorReporter) {
-    val process = VariousCleanups(program, errors)
+internal fun Program.variousCleanups(errors: IErrorReporter, options: CompilationOptions) {
+    val process = VariousCleanups(this, errors, options)
     process.visit(this)
     if(errors.noErrors())
         process.applyModifications()
 }
 
-
 internal fun Program.moveMainAndStartToFirst() {
     // the module containing the program entrypoint is moved to the first in the sequence.
     // the "main" block containing the entrypoint is moved to the top in there,
@@ -166,46 +138,10 @@ internal fun Program.moveMainAndStartToFirst() {
     }
 }
 
-internal fun AssignTarget.isInRegularRAMof(machine: IMachineDefinition): Boolean {
-    val memAddr = memoryAddress
-    val arrayIdx = arrayindexed
-    val ident = identifier
-    when {
-        memAddr != null -> {
-            return when (memAddr.addressExpression) {
-                is NumericLiteralValue -> {
-                    machine.isRegularRAMaddress((memAddr.addressExpression as NumericLiteralValue).number.toInt())
-                }
-                is IdentifierReference -> {
-                    val program = definingModule.program
-                    val decl = (memAddr.addressExpression as IdentifierReference).targetVarDecl(program)
-                    if ((decl?.type == VarDeclType.VAR || decl?.type == VarDeclType.CONST) && decl.value is NumericLiteralValue)
-                        machine.isRegularRAMaddress((decl.value as NumericLiteralValue).number.toInt())
-                    else
-                        false
-                }
-                else -> false
-            }
-        }
-        arrayIdx != null -> {
-            val program = definingModule.program
-            val targetStmt = arrayIdx.arrayvar.targetVarDecl(program)
-            return if (targetStmt?.type == VarDeclType.MEMORY) {
-                val addr = targetStmt.value as? NumericLiteralValue
-                if (addr != null)
-                    machine.isRegularRAMaddress(addr.number.toInt())
-                else
-                    false
-            } else true
-        }
-        ident != null -> {
-            val program = definingModule.program
-            val decl = ident.targetVarDecl(program)!!
-            return if (decl.type == VarDeclType.MEMORY && decl.value is NumericLiteralValue)
-                machine.isRegularRAMaddress((decl.value as NumericLiteralValue).number.toInt())
-            else
-                true
-        }
-        else -> return true
+internal fun IdentifierReference.isSubroutineParameter(program: Program): Boolean {
+    val vardecl = this.targetVarDecl(program)
+    if(vardecl!=null && vardecl.origin==VarDeclOrigin.SUBROUTINEPARAM) {
+        return vardecl.definingSubroutine?.parameters?.any { it.name==vardecl.name } == true
     }
+    return false
 }

compiler/src/prog8/compiler/astprocessing/AstIdentifiersChecker.kt

@@ -1,15 +1,21 @@
 package prog8.compiler.astprocessing
 
+import prog8.ast.IFunctionCall
+import prog8.ast.Node
 import prog8.ast.Program
 import prog8.ast.base.Position
+import prog8.ast.expressions.FunctionCallExpression
 import prog8.ast.expressions.StringLiteralValue
 import prog8.ast.statements.*
 import prog8.ast.walk.IAstVisitor
-import prog8.compiler.IErrorReporter
-import prog8.compiler.functions.BuiltinFunctions
-import prog8.compiler.target.ICompilationTarget
+import prog8.compilerinterface.BuiltinFunctions
+import prog8.compilerinterface.Encoding
+import prog8.compilerinterface.ICompilationTarget
+import prog8.compilerinterface.IErrorReporter
 
-internal class AstIdentifiersChecker(private val program: Program, private val errors: IErrorReporter, private val compTarget: ICompilationTarget) : IAstVisitor {
+internal class AstIdentifiersChecker(private val errors: IErrorReporter,
+                                     private val program: Program,
+                                     private val compTarget: ICompilationTarget) : IAstVisitor {
     private var blocks = mutableMapOf<String, Block>()
 
     private fun nameError(name: String, position: Position, existing: Statement) {
@@ -42,7 +48,7 @@ internal class AstIdentifiersChecker(private val program: Program, private val e
         if(decl.name in compTarget.machine.opcodeNames)
             errors.err("can't use a cpu opcode name as a symbol: '${decl.name}'", decl.position)
 
-        val existing = program.namespace.lookup(listOf(decl.name), decl)
+        val existing = decl.definingScope.lookup(listOf(decl.name))
         if (existing != null && existing !== decl)
             nameError(decl.name, decl.position, existing)
 
@@ -65,22 +71,19 @@ internal class AstIdentifiersChecker(private val program: Program, private val e
             // if (subroutine.parameters.any { it.name in BuiltinFunctions })
             //    checkResult.add(NameError("builtin function name cannot be used as parameter", subroutine.position))
 
-            val existing = program.namespace.lookup(listOf(subroutine.name), subroutine)
+            val existing = subroutine.lookup(listOf(subroutine.name))
             if (existing != null && existing !== subroutine)
                 nameError(subroutine.name, subroutine.position, existing)
 
-            // check that there are no local variables, labels, or other subs that redefine the subroutine's parameters. Blocks are okay.
+            // check that there are no local symbols (variables, labels, subs) that redefine the subroutine's parameters.
             val symbolsInSub = subroutine.allDefinedSymbols
             val namesInSub = symbolsInSub.map{ it.first }.toSet()
             val paramNames = subroutine.parameters.map { it.name }.toSet()
             val paramsToCheck = paramNames.intersect(namesInSub)
             for(name in paramsToCheck) {
-                val labelOrVar = subroutine.getLabelOrVariable(name)
-                if(labelOrVar!=null && labelOrVar.position != subroutine.position)
-                    nameError(name, labelOrVar.position, subroutine)
-                val sub = subroutine.statements.firstOrNull { it is Subroutine && it.name==name}
-                if(sub!=null)
-                    nameError(name, subroutine.position, sub)
+                val symbol = subroutine.searchSymbol(name)
+                if(symbol!=null && (symbol as? VarDecl)?.subroutineParameter==null)
+                    nameError(name, symbol.position, subroutine)
             }
 
             if(subroutine.isAsmSubroutine && subroutine.statements.any{it !is InlineAssembly}) {
@@ -125,4 +128,46 @@ internal class AstIdentifiersChecker(private val program: Program, private val e
 
         super.visit(string)
     }
+
+    override fun visit(functionCallExpr: FunctionCallExpression) =  visitFunctionCall(functionCallExpr)
+    override fun visit(functionCallStatement: FunctionCallStatement) =  visitFunctionCall(functionCallStatement)
+
+    private fun visitFunctionCall(call: IFunctionCall) {
+        when (val target = call.target.targetStatement(program)) {
+            is Subroutine -> {
+                if(call.args.size != target.parameters.size) {
+                    val pos = (if(call.args.any()) call.args[0] else (call as Node)).position
+                    errors.err("invalid number of arguments", pos)
+                }
+            }
+            is BuiltinFunctionPlaceholder -> {
+                val func = BuiltinFunctions.getValue(target.name)
+                if(call.args.size != func.parameters.size) {
+                    val pos = (if(call.args.any()) call.args[0] else (call as Node)).position
+                    errors.err("invalid number of arguments", pos)
+                }
+                if(func.name=="memory") {
+                    val name = call.args[0] as? StringLiteralValue
+                    if(name!=null) {
+                        val processed = name.value.map {
+                            if(it.isLetterOrDigit())
+                                it
+                            else
+                                '_'
+                        }.joinToString("")
+                        call.args[0] = StringLiteralValue(processed, Encoding.PETSCII, name.position)
+                        call.args[0].linkParents(call as Node)
+                    }
+                }
+            }
+            is Label -> {
+                if(call.args.isNotEmpty()) {
+                    val pos = (if(call.args.any()) call.args[0] else (call as Node)).position
+                    errors.err("cannot use arguments when calling a label", pos)
+                }
+            }
+            null -> {}
+            else -> errors.err("cannot call this as a subroutine or function", call.target.position)
+        }
+    }
 }

compiler/src/prog8/compiler/astprocessing/AstPreprocessor.kt

@@ -0,0 +1,100 @@
+package prog8.compiler.astprocessing
+
+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.IErrorReporter
+
+
+class AstPreprocessor(val program: Program, val errors: IErrorReporter) : AstWalker() {
+
+    override fun after(range: RangeExpression, parent: Node): Iterable<IAstModification> {
+        // has to be done before the constant folding, otherwise certain checks there will fail on invalid range sizes
+        val modifications = mutableListOf<IAstModification>()
+        if(range.from !is NumericLiteralValue) {
+            try {
+                val constval = range.from.constValue(program)
+                if (constval != null)
+                    modifications += IAstModification.ReplaceNode(range.from, constval, range)
+            } catch (x: SyntaxError) {
+                // syntax errors will be reported later
+            }
+        }
+        if(range.to !is NumericLiteralValue) {
+            try {
+                val constval = range.to.constValue(program)
+                if(constval!=null)
+                    modifications += IAstModification.ReplaceNode(range.to, constval, range)
+            } catch (x: SyntaxError) {
+                // syntax errors will be reported later
+            }
+        }
+        if(range.step !is NumericLiteralValue) {
+            try {
+                val constval = range.step.constValue(program)
+                if(constval!=null)
+                    modifications += IAstModification.ReplaceNode(range.step, constval, range)
+            } catch (x: SyntaxError) {
+                // syntax errors will be reported later
+            }
+        }
+        return modifications
+    }
+
+    override fun before(scope: AnonymousScope, parent: Node): Iterable<IAstModification> {
+
+        // move vardecls in Anonymous scope up to the containing subroutine
+        // and add initialization assignment in its place if needed
+        val vars = scope.statements.asSequence().filterIsInstance<VarDecl>()
+        val parentscope = scope.definingScope
+        if(vars.any() && parentscope !== parent) {
+            val movements = mutableListOf<IAstModification>()
+            val replacements = mutableListOf<IAstModification>()
+
+            for(decl in vars) {
+                if(decl.type != VarDeclType.VAR) {
+                    movements.add(IAstModification.InsertFirst(decl, parentscope))
+                    replacements.add(IAstModification.Remove(decl, scope))
+                } else {
+                    if(decl.value!=null && decl.datatype in NumericDatatypes) {
+                        val target = AssignTarget(IdentifierReference(listOf(decl.name), decl.position), null, null, decl.position)
+                        val assign = Assignment(target, decl.value!!, AssignmentOrigin.VARINIT, decl.position)
+                        replacements.add(IAstModification.ReplaceNode(decl, assign, scope))
+                        decl.value = null
+                        decl.allowInitializeWithZero = false
+                    } else {
+                        replacements.add(IAstModification.Remove(decl, scope))
+                    }
+                    movements.add(IAstModification.InsertFirst(decl, parentscope))
+                }
+            }
+            return movements + replacements
+        }
+        return noModifications
+    }
+
+    override fun after(expr: BinaryExpression, parent: Node): Iterable<IAstModification> {
+        // this has to be done here becuse otherwise the string / range literal values will have been replaced by variables
+        if(expr.operator=="in") {
+            val containment = ContainmentCheck(expr.left, expr.right, expr.position)
+            return listOf(IAstModification.ReplaceNode(expr, containment, parent))
+        }
+        return noModifications
+    }
+
+    override fun after(decl: VarDecl, parent: Node): Iterable<IAstModification> {
+        val nextAssignment = decl.nextSibling() as? Assignment
+        if(nextAssignment!=null && nextAssignment.origin!=AssignmentOrigin.VARINIT) {
+            // check if it's a proper initializer assignment for the variable
+            if(decl.value==null && nextAssignment.target.identifier?.targetVarDecl(program)===decl) {
+                if(!nextAssignment.value.referencesIdentifier(nextAssignment.target.identifier!!.nameInSource))
+                    nextAssignment.origin = AssignmentOrigin.VARINIT
+            }
+        }
+        return noModifications
+    }
+}

compiler/src/prog8/compiler/astprocessing/AstVariousTransforms.kt

@@ -20,13 +20,13 @@ internal class AstVariousTransforms(private val program: Program) : AstWalker()
         val symbolsInSub = subroutine.allDefinedSymbols
         val namesInSub = symbolsInSub.map{ it.first }.toSet()
         if(subroutine.asmAddress==null) {
-            if(subroutine.asmParameterRegisters.isEmpty() && subroutine.parameters.isNotEmpty()) {
-                val vars = subroutine.statements.filterIsInstance<VarDecl>().map { it.name }.toSet()
+            if(!subroutine.isAsmSubroutine && subroutine.parameters.isNotEmpty()) {
+                val vars = subroutine.statements.asSequence().filterIsInstance<VarDecl>().map { it.name }.toSet()
                 if(!vars.containsAll(subroutine.parameters.map{it.name})) {
                     return subroutine.parameters
                             .filter { it.name !in namesInSub }
                             .map {
-                                val vardecl = ParameterVarDecl(it.name, it.type, subroutine.position)
+                                val vardecl = VarDecl.fromParameter(it)
                                 IAstModification.InsertFirst(vardecl, subroutine)
                             }
                 }
@@ -49,7 +49,7 @@ internal class AstVariousTransforms(private val program: Program) : AstWalker()
                 val amount = expr.right.constValue(program)
                 if(amount!=null) {
                     val string = leftStr.value.repeat(amount.number.toInt())
-                    val strval = StringLiteralValue(string, leftStr.altEncoding, expr.position)
+                    val strval = StringLiteralValue(string, leftStr.encoding, expr.position)
                     return listOf(IAstModification.ReplaceNode(expr, strval, parent))
                 }
             }
@@ -57,7 +57,7 @@ internal class AstVariousTransforms(private val program: Program) : AstWalker()
                 val amount = expr.right.constValue(program)
                 if(amount!=null) {
                     val string = rightStr.value.repeat(amount.number.toInt())
-                    val strval = StringLiteralValue(string, rightStr.altEncoding, expr.position)
+                    val strval = StringLiteralValue(string, rightStr.encoding, expr.position)
                     return listOf(IAstModification.ReplaceNode(expr, strval, parent))
                 }
             }
@@ -67,7 +67,7 @@ internal class AstVariousTransforms(private val program: Program) : AstWalker()
     }
 
     override fun after(arrayIndexedExpression: ArrayIndexedExpression, parent: Node): Iterable<IAstModification> {
-        return replacePointerVarIndexWithMemread(program, arrayIndexedExpression, parent)
+        return replacePointerVarIndexWithMemreadOrMemwrite(program, arrayIndexedExpression, parent)
     }
 
     private fun concatString(expr: BinaryExpression): StringLiteralValue? {
@@ -80,17 +80,17 @@ internal class AstVariousTransforms(private val program: Program) : AstWalker()
                 if(subStrVal==null)
                     null
                 else
-                    StringLiteralValue("${subStrVal.value}${rightStrval.value}", subStrVal.altEncoding, rightStrval.position)
+                    StringLiteralValue("${subStrVal.value}${rightStrval.value}", subStrVal.encoding, rightStrval.position)
             }
             expr.right is BinaryExpression && leftStrval!=null -> {
                 val subStrVal = concatString(expr.right as BinaryExpression)
                 if(subStrVal==null)
                     null
                 else
-                    StringLiteralValue("${leftStrval.value}${subStrVal.value}", subStrVal.altEncoding, leftStrval.position)
+                    StringLiteralValue("${leftStrval.value}${subStrVal.value}", subStrVal.encoding, leftStrval.position)
             }
             leftStrval!=null && rightStrval!=null -> {
-                StringLiteralValue("${leftStrval.value}${rightStrval.value}", leftStrval.altEncoding, leftStrval.position)
+                StringLiteralValue("${leftStrval.value}${rightStrval.value}", leftStrval.encoding, leftStrval.position)
             }
             else -> null
         }
@@ -99,12 +99,12 @@ internal class AstVariousTransforms(private val program: Program) : AstWalker()
 
 
 
-internal fun replacePointerVarIndexWithMemread(program: Program, arrayIndexedExpression: ArrayIndexedExpression, parent: Node): Iterable<IAstModification> {
+internal fun replacePointerVarIndexWithMemreadOrMemwrite(program: Program, arrayIndexedExpression: ArrayIndexedExpression, parent: Node): Iterable<IAstModification> {
     val arrayVar = arrayIndexedExpression.arrayvar.targetVarDecl(program)
     if(arrayVar!=null && arrayVar.datatype ==  DataType.UWORD) {
         // rewrite   pointervar[index]  into  @(pointervar+index)
         val indexer = arrayIndexedExpression.indexer
-        val add = BinaryExpression(arrayIndexedExpression.arrayvar, "+", indexer.indexExpr, arrayIndexedExpression.position)
+        val add = BinaryExpression(arrayIndexedExpression.arrayvar.copy(), "+", indexer.indexExpr, arrayIndexedExpression.position)
         return if(parent is AssignTarget) {
             // we're part of the target of an assignment, we have to actually change the assign target itself
             val memwrite = DirectMemoryWrite(add, arrayIndexedExpression.position)

compiler/src/prog8/compiler/astprocessing/BeforeAsmAstChanger.kt

@@ -0,0 +1,371 @@
+package prog8.compiler.astprocessing
+
+import prog8.ast.IFunctionCall
+import prog8.ast.IStatementContainer
+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.ast.walk.IAstVisitor
+import prog8.codegen.target.AssemblyError
+import prog8.compilerinterface.CompilationOptions
+import prog8.compilerinterface.IErrorReporter
+import prog8.compilerinterface.isIOAddress
+import prog8.optimizer.getTempVarName
+
+internal class BeforeAsmAstChanger(val program: Program, private val options: CompilationOptions,
+                                   private val errors: IErrorReporter
+) : AstWalker() {
+
+    private val subroutineVariables = mutableMapOf<Subroutine, MutableList<Pair<String, VarDecl>>>()
+
+    private fun rememberSubroutineVar(decl: VarDecl) {
+        val sub = decl.definingSubroutine ?: return
+        var varsList = subroutineVariables[sub]
+        if(varsList==null) {
+            varsList = mutableListOf()
+            subroutineVariables[sub] = varsList
+        }
+        varsList.add(decl.name to decl)
+    }
+
+    override fun before(breakStmt: Break, parent: Node): Iterable<IAstModification> {
+        throw FatalAstException("break should have been replaced by goto $breakStmt")
+    }
+
+    override fun before(whileLoop: WhileLoop, parent: Node): Iterable<IAstModification> {
+        throw FatalAstException("while should have been converted to jumps")
+    }
+
+    override fun before(untilLoop: UntilLoop, parent: Node): Iterable<IAstModification> {
+        throw FatalAstException("do..until should have been converted to jumps")
+    }
+
+    override fun before(block: Block, parent: Node): Iterable<IAstModification> {
+        // move all subroutines to the bottom of the block
+        val subs = block.statements.filterIsInstance<Subroutine>()
+        block.statements.removeAll(subs)
+        block.statements.addAll(subs)
+        return noModifications
+    }
+
+    override fun after(decl: VarDecl, parent: Node): Iterable<IAstModification> {
+        if(decl.type== VarDeclType.VAR && decl.value != null && decl.datatype in NumericDatatypes)
+            throw FatalAstException("vardecls for variables, with initial numerical value, should have been rewritten as plain vardecl + assignment $decl")
+        rememberSubroutineVar(decl)
+        return noModifications
+    }
+
+    override fun after(assignment: Assignment, parent: Node): Iterable<IAstModification> {
+        // Try to replace A = B <operator> Something  by A= B, A = A <operator> Something
+        // this triggers the more efficent augmented assignment code generation more often.
+        // But it can only be done if the target variable IS NOT OCCURRING AS AN OPERAND ITSELF.
+        if(!assignment.isAugmentable
+            && assignment.target.identifier != null
+            && !assignment.target.isIOAddress(options.compTarget.machine)) {
+            val binExpr = assignment.value as? BinaryExpression
+
+            if(binExpr!=null && binExpr.inferType(program) istype DataType.FLOAT && !options.optimizeFloatExpressions)
+                return noModifications
+
+            if (binExpr != null && binExpr.operator !in ComparisonOperators) {
+                if (binExpr.left !is BinaryExpression) {
+                    if (binExpr.right.referencesIdentifier(assignment.target.identifier!!.nameInSource)) {
+                        // the right part of the expression contains the target variable itself.
+                        // we can't 'split' it trivially because the variable will be changed halfway through.
+                        if(binExpr.operator in AssociativeOperators) {
+                            // A = <something-without-A>  <associativeoperator>  <otherthing-with-A>
+                            // use the other part of the expression to split.
+                            val sourceDt = binExpr.right.inferType(program).getOrElse { throw AssemblyError("unknown dt") }
+                            val (_, right) = binExpr.right.typecastTo(assignment.target.inferType(program).getOrElse { throw AssemblyError(
+                                "unknown dt"
+                            )
+                            }, sourceDt, implicit=true)
+                            val assignRight = Assignment(assignment.target, right, AssignmentOrigin.BEFOREASMGEN, assignment.position)
+                            return listOf(
+                                IAstModification.InsertBefore(assignment, assignRight, parent as IStatementContainer),
+                                IAstModification.ReplaceNode(binExpr.right, binExpr.left, binExpr),
+                                IAstModification.ReplaceNode(binExpr.left, assignment.target.toExpression(), binExpr)
+                            )
+                        }
+                    } else {
+                        val sourceDt = binExpr.left.inferType(program).getOrElse { throw AssemblyError("unknown dt") }
+                        val (_, left) = binExpr.left.typecastTo(assignment.target.inferType(program).getOrElse { throw AssemblyError(
+                            "unknown dt"
+                        )
+                        }, sourceDt, implicit=true)
+                        val assignLeft = Assignment(assignment.target, left, AssignmentOrigin.BEFOREASMGEN, assignment.position)
+                        return listOf(
+                            IAstModification.InsertBefore(assignment, assignLeft, parent as IStatementContainer),
+                            IAstModification.ReplaceNode(binExpr.left, assignment.target.toExpression(), binExpr)
+                        )
+                    }
+                }
+            }
+        }
+        return noModifications
+    }
+
+    override fun after(scope: AnonymousScope, parent: Node): Iterable<IAstModification> {
+        if(scope.statements.any { it is VarDecl || it is IStatementContainer })
+            throw FatalAstException("anonymousscope may no longer contain any vardecls or subscopes")
+        return noModifications
+    }
+
+    override fun after(subroutine: Subroutine, parent: Node): Iterable<IAstModification> {
+        val firstDeclarations = mutableMapOf<String, VarDecl>()
+        val rememberedSubroutineVars = subroutineVariables.getOrDefault(subroutine, mutableListOf())
+        for(decl in rememberedSubroutineVars) {
+            val existing = firstDeclarations[decl.first]
+            if(existing!=null && existing !== decl.second) {
+                errors.err("variable ${decl.first} already defined in subroutine ${subroutine.name} at ${existing.position}", decl.second.position)
+            } else {
+                firstDeclarations[decl.first] = decl.second
+            }
+        }
+        rememberedSubroutineVars.clear()
+
+        // add the implicit return statement at the end (if it's not there yet), but only if it's not a kernal routine.
+        // and if an assembly block doesn't contain a rts/rti, and some other situations.
+        val mods = mutableListOf<IAstModification>()
+        val returnStmt = Return(null, subroutine.position)
+        if (subroutine.asmAddress == null && !subroutine.inline) {
+            if(subroutine.statements.isEmpty() ||
+                (subroutine.amountOfRtsInAsm() == 0
+                        && subroutine.statements.lastOrNull { it !is VarDecl } !is Return
+                        && subroutine.statements.last() !is Subroutine)) {
+                mods += IAstModification.InsertLast(returnStmt, subroutine)
+            }
+        }
+
+        // precede a subroutine with a return to avoid falling through into the subroutine from code above it
+        val outerScope = subroutine.definingScope
+        val outerStatements = outerScope.statements
+        val subroutineStmtIdx = outerStatements.indexOf(subroutine)
+        if (subroutineStmtIdx > 0) {
+            val prevStmt = outerStatements[subroutineStmtIdx-1]
+            if(outerScope !is Block
+                && (prevStmt !is Jump)
+                && prevStmt !is Subroutine
+                && prevStmt !is Return
+            ) {
+                mods += IAstModification.InsertAfter(outerStatements[subroutineStmtIdx - 1], returnStmt, outerScope)
+            }
+        }
+        return mods
+    }
+
+    override fun after(ifElse: IfElse, parent: Node): Iterable<IAstModification> {
+        val prefixExpr = ifElse.condition as? PrefixExpression
+        if(prefixExpr!=null && prefixExpr.operator=="not") {
+            // if not x -> if x==0
+            val booleanExpr = BinaryExpression(
+                prefixExpr.expression,
+                "==",
+                NumericLiteralValue.optimalInteger(0, ifElse.condition.position),
+                ifElse.condition.position
+            )
+            return listOf(IAstModification.ReplaceNode(ifElse.condition, booleanExpr, ifElse))
+        }
+
+        val binExpr = ifElse.condition as? BinaryExpression
+        if(binExpr==null || binExpr.operator !in ComparisonOperators) {
+            // if x  ->  if x!=0,    if x+5  ->  if x+5 != 0
+            val booleanExpr = BinaryExpression(
+                ifElse.condition,
+                "!=",
+                NumericLiteralValue.optimalInteger(0, ifElse.condition.position),
+                ifElse.condition.position
+            )
+            return listOf(IAstModification.ReplaceNode(ifElse.condition, booleanExpr, ifElse))
+        }
+
+        if((binExpr.left as? NumericLiteralValue)?.number==0.0 &&
+            (binExpr.right as? NumericLiteralValue)?.number!=0.0)
+            throw FatalAstException("0==X should have been swapped to if X==0")
+
+        // simplify the conditional expression, introduce simple assignments if required.
+        // NOTE: sometimes this increases code size because additional stores/loads are generated for the
+        //       intermediate variables. We assume these are optimized away from the resulting assembly code later.
+        val simplify = simplifyConditionalExpression(binExpr)
+        val modifications = mutableListOf<IAstModification>()
+        if(simplify.rightVarAssignment!=null) {
+            modifications += IAstModification.ReplaceNode(binExpr.right, simplify.rightOperandReplacement!!, binExpr)
+            modifications += IAstModification.InsertBefore(
+                ifElse,
+                simplify.rightVarAssignment,
+                parent as IStatementContainer
+            )
+        }
+        if(simplify.leftVarAssignment!=null) {
+            modifications += IAstModification.ReplaceNode(binExpr.left, simplify.leftOperandReplacement!!, binExpr)
+            modifications += IAstModification.InsertBefore(
+                ifElse,
+                simplify.leftVarAssignment,
+                parent as IStatementContainer
+            )
+        }
+
+        return modifications
+    }
+
+    private class CondExprSimplificationResult(
+        val leftVarAssignment: Assignment?,
+        val leftOperandReplacement: Expression?,
+        val rightVarAssignment: Assignment?,
+        val rightOperandReplacement: Expression?
+    )
+
+    private fun simplifyConditionalExpression(expr: BinaryExpression): CondExprSimplificationResult {
+
+        // TODO: somehow figure out if the expr will result in stack-evaluation STILL after being split off,
+        //       in that case: do *not* split it off but just keep it as it is (otherwise code size increases)
+        // TODO: this should be replaced by a general expression-evaluation optimization step.
+        //       the actual conditional expression in the statement should be no more than VARIABLE <COMPARISON-OPERATOR> SIMPLE-EXPRESSION
+        // NOTE: do NOT move this to an earler ast transform phase (such as StatementReorderer or StatementOptimizer) - it WILL result in larger code.
+
+        var leftAssignment: Assignment? = null
+        var leftOperandReplacement: Expression? = null
+        var rightAssignment: Assignment? = null
+        var rightOperandReplacement: Expression? = null
+
+        val separateLeftExpr = !expr.left.isSimple && expr.left !is IFunctionCall && expr.left !is ContainmentCheck
+        val separateRightExpr = !expr.right.isSimple && expr.right !is IFunctionCall && expr.right !is ContainmentCheck
+        val leftDt = expr.left.inferType(program)
+        val rightDt = expr.right.inferType(program)
+
+        if(!leftDt.isInteger || !rightDt.isInteger) {
+            // we can't reasonably simplify non-integer expressions
+            return CondExprSimplificationResult(null, null, null, null)
+        }
+
+        if(separateLeftExpr) {
+            val name = getTempVarName(leftDt)
+            leftOperandReplacement = IdentifierReference(name, expr.position)
+            leftAssignment = Assignment(
+                AssignTarget(IdentifierReference(name, expr.position), null, null, expr.position),
+                expr.left,
+                AssignmentOrigin.BEFOREASMGEN, expr.position
+            )
+        }
+        if(separateRightExpr) {
+            val name = when {
+                rightDt istype DataType.UBYTE -> listOf("prog8_lib","retval_interm_ub")
+                rightDt istype DataType.UWORD -> listOf("prog8_lib","retval_interm_uw")
+                rightDt istype DataType.BYTE -> listOf("prog8_lib","retval_interm_b2")
+                rightDt istype DataType.WORD -> listOf("prog8_lib","retval_interm_w2")
+                else -> throw AssemblyError("invalid dt")
+            }
+            rightOperandReplacement = IdentifierReference(name, expr.position)
+            rightAssignment = Assignment(
+                AssignTarget(IdentifierReference(name, expr.position), null, null, expr.position),
+                expr.right,
+                AssignmentOrigin.BEFOREASMGEN, expr.position
+            )
+        }
+        return CondExprSimplificationResult(
+            leftAssignment, leftOperandReplacement,
+            rightAssignment, rightOperandReplacement
+        )
+    }
+
+    override fun after(functionCallStatement: FunctionCallStatement, parent: Node): Iterable<IAstModification> {
+        if(functionCallStatement.target.nameInSource==listOf("cmp")) {
+            // if the datatype of the arguments of cmp() are different, cast the byte one to word.
+            val arg1 = functionCallStatement.args[0]
+            val arg2 = functionCallStatement.args[1]
+            val dt1 = arg1.inferType(program).getOr(DataType.UNDEFINED)
+            val dt2 = arg2.inferType(program).getOr(DataType.UNDEFINED)
+            if(dt1 in ByteDatatypes) {
+                if(dt2 in ByteDatatypes)
+                    return noModifications
+                val (replaced, cast) = arg1.typecastTo(if(dt1== DataType.UBYTE) DataType.UWORD else DataType.WORD, dt1, true)
+                if(replaced)
+                    return listOf(IAstModification.ReplaceNode(arg1, cast, functionCallStatement))
+            } else {
+                if(dt2 in WordDatatypes)
+                    return noModifications
+                val (replaced, cast) = arg2.typecastTo(if(dt2== DataType.UBYTE) DataType.UWORD else DataType.WORD, dt2, true)
+                if(replaced)
+                    return listOf(IAstModification.ReplaceNode(arg2, cast, functionCallStatement))
+            }
+        }
+        return noModifications
+    }
+
+    override fun after(arrayIndexedExpression: ArrayIndexedExpression, parent: Node): Iterable<IAstModification> {
+
+        val containingStatement = getContainingStatement(arrayIndexedExpression)
+        if(getComplexArrayIndexedExpressions(containingStatement).size > 1) {
+            errors.err("it's not possible to use more than one complex array indexing expression in a single statement; break it up via a temporary variable for instance", containingStatement.position)
+            return noModifications
+        }
+
+
+        val index = arrayIndexedExpression.indexer.indexExpr
+        if(index !is NumericLiteralValue && index !is IdentifierReference) {
+            // replace complex indexing expression with a temp variable to hold the computed index first
+            return getAutoIndexerVarFor(arrayIndexedExpression)
+        }
+
+        return noModifications
+    }
+
+    private fun getComplexArrayIndexedExpressions(stmt: Statement): List<ArrayIndexedExpression> {
+
+        class Searcher : IAstVisitor {
+            val complexArrayIndexedExpressions = mutableListOf<ArrayIndexedExpression>()
+            override fun visit(arrayIndexedExpression: ArrayIndexedExpression) {
+                val ix = arrayIndexedExpression.indexer.indexExpr
+                if(ix !is NumericLiteralValue && ix !is IdentifierReference)
+                    complexArrayIndexedExpressions.add(arrayIndexedExpression)
+            }
+
+            override fun visit(branch: Branch) {}
+
+            override fun visit(forLoop: ForLoop) {}
+
+            override fun visit(ifElse: IfElse) {
+                ifElse.condition.accept(this)
+            }
+
+            override fun visit(untilLoop: UntilLoop) {
+                untilLoop.condition.accept(this)
+            }
+        }
+
+        val searcher = Searcher()
+        stmt.accept(searcher)
+        return searcher.complexArrayIndexedExpressions
+    }
+
+    private fun getContainingStatement(expression: Expression): Statement {
+        var node: Node = expression
+        while(node !is Statement)
+            node = node.parent
+
+        return node
+    }
+
+    private fun getAutoIndexerVarFor(expr: ArrayIndexedExpression): MutableList<IAstModification> {
+        val modifications = mutableListOf<IAstModification>()
+        val statement = expr.containingStatement
+        val dt = expr.indexer.indexExpr.inferType(program)
+        val tempvar = if(dt.isBytes) listOf("prog8_lib","retval_interm_ub") else listOf("prog8_lib","retval_interm_b")
+        val target = AssignTarget(IdentifierReference(tempvar, expr.indexer.position), null, null, expr.indexer.position)
+        val assign = Assignment(target, expr.indexer.indexExpr, AssignmentOrigin.BEFOREASMGEN, expr.indexer.position)
+        modifications.add(IAstModification.InsertBefore(statement, assign, statement.parent as IStatementContainer))
+        modifications.add(
+            IAstModification.ReplaceNode(
+                expr.indexer.indexExpr,
+                target.identifier!!.copy(),
+                expr.indexer
+            )
+        )
+        return modifications
+    }
+
+}

compiler/src/prog8/compiler/astprocessing/BeforeAsmTypecastCleaner.kt

@@ -0,0 +1,76 @@
+package prog8.compiler.astprocessing
+
+import prog8.ast.IFunctionCall
+import prog8.ast.Node
+import prog8.ast.Program
+import prog8.ast.base.ByteDatatypes
+import prog8.ast.base.DataType
+import prog8.ast.base.PassByReferenceDatatypes
+import prog8.ast.base.WordDatatypes
+import prog8.ast.expressions.AddressOf
+import prog8.ast.expressions.Expression
+import prog8.ast.expressions.IdentifierReference
+import prog8.ast.expressions.TypecastExpression
+import prog8.ast.walk.AstWalker
+import prog8.ast.walk.IAstModification
+import prog8.compilerinterface.IErrorReporter
+
+internal class BeforeAsmTypecastCleaner(val program: Program,
+                                        private val errors: IErrorReporter
+) : AstWalker() {
+
+    override fun after(typecast: TypecastExpression, parent: Node): Iterable<IAstModification> {
+        // see if we can remove redundant typecasts (outside of expressions)
+        // such as casting byte<->ubyte,  word<->uword  or even redundant casts (sourcetype = target type).
+        // Also the special typecast of a reference type (str, array) to an UWORD will be changed into address-of,
+        //   UNLESS it's a str parameter in the containing subroutine - then we remove the typecast altogether
+        val sourceDt = typecast.expression.inferType(program).getOr(DataType.UNDEFINED)
+        if (typecast.type in ByteDatatypes && sourceDt in ByteDatatypes
+            || typecast.type in WordDatatypes && sourceDt in WordDatatypes
+        ) {
+            if(typecast.parent !is Expression) {
+                return listOf(IAstModification.ReplaceNode(typecast, typecast.expression, parent))
+            }
+        }
+
+        if(typecast.type==sourceDt)
+            return listOf(IAstModification.ReplaceNode(typecast, typecast.expression, parent))
+
+        if(sourceDt in PassByReferenceDatatypes) {
+            if(typecast.type== DataType.UWORD) {
+                val identifier = typecast.expression as? IdentifierReference
+                if(identifier!=null) {
+                    return if(identifier.isSubroutineParameter(program)) {
+                        listOf(
+                            IAstModification.ReplaceNode(
+                                typecast,
+                                typecast.expression,
+                                parent
+                            )
+                        )
+                    } else {
+                        listOf(
+                            IAstModification.ReplaceNode(
+                                typecast,
+                                AddressOf(identifier, typecast.position),
+                                parent
+                            )
+                        )
+                    }
+                } else if(typecast.expression is IFunctionCall) {
+                    return listOf(
+                        IAstModification.ReplaceNode(
+                            typecast,
+                            typecast.expression,
+                            parent
+                        )
+                    )
+                }
+            } else {
+                errors.err("cannot cast pass-by-reference value to type ${typecast.type} (only to UWORD)", typecast.position)
+            }
+        }
+
+        return noModifications
+    }
+}

compiler/src/prog8/compiler/astprocessing/CodeDesugarer.kt

@@ -0,0 +1,137 @@
+package prog8.compiler.astprocessing
+
+import prog8.ast.IFunctionCall
+import prog8.ast.IStatementContainer
+import prog8.ast.Node
+import prog8.ast.Program
+import prog8.ast.base.ParentSentinel
+import prog8.ast.base.Position
+import prog8.ast.expressions.*
+import prog8.ast.statements.*
+import prog8.ast.walk.AstWalker
+import prog8.ast.walk.IAstModification
+import prog8.compilerinterface.*
+
+
+internal class CodeDesugarer(val program: Program, private val errors: IErrorReporter) : AstWalker() {
+
+    // Some more code shuffling to simplify the Ast that the codegenerator has to process.
+    // Several changes have already been done by the StatementReorderer !
+    // But the ones here are simpler and are repeated once again after all optimization steps
+    // have been performed (because those could re-introduce nodes that have to be desugared)
+    //
+    // List of modifications:
+    // - replace 'break' statements by a goto + generated after label.
+    // - replace while and do-until loops by just jumps.
+    // - replace peek() and poke() by direct memory accesses.
+
+
+    private var generatedLabelSequenceNumber: Int = 0
+    private val generatedLabelPrefix = "prog8_label_"
+
+    private fun makeLabel(postfix: String, position: Position): Label {
+        generatedLabelSequenceNumber++
+        return Label("${generatedLabelPrefix}${generatedLabelSequenceNumber}_$postfix", position)
+    }
+
+    private fun jumpLabel(label: Label): Jump {
+        val ident = IdentifierReference(listOf(label.name), label.position)
+        return Jump(null, ident, null, label.position)
+    }
+
+    override fun before(breakStmt: Break, parent: Node): Iterable<IAstModification> {
+        fun jumpAfter(stmt: Statement): Iterable<IAstModification> {
+            val label = makeLabel("after", breakStmt.position)
+            return listOf(
+                IAstModification.ReplaceNode(breakStmt, jumpLabel(label), parent),
+                IAstModification.InsertAfter(stmt, label, stmt.parent as IStatementContainer)
+            )
+        }
+
+        var partof = parent
+        while(true) {
+            when (partof) {
+                is Subroutine, is Block, is ParentSentinel -> {
+                    errors.err("break in wrong scope", breakStmt.position)
+                    return noModifications
+                }
+                is ForLoop,
+                is RepeatLoop,
+                is UntilLoop,
+                is WhileLoop -> return jumpAfter(partof as Statement)
+                else -> partof = partof.parent
+            }
+        }
+    }
+
+    override fun after(untilLoop: UntilLoop, parent: Node): Iterable<IAstModification> {
+        /*
+do { STUFF } until CONDITION
+    ===>
+_loop:
+  STUFF
+if not CONDITION
+   goto _loop
+         */
+        val pos = untilLoop.position
+        val loopLabel = makeLabel("untilloop", pos)
+        val notCondition = PrefixExpression("not", untilLoop.condition, pos)
+        val replacement = AnonymousScope(mutableListOf(
+            loopLabel,
+            untilLoop.body,
+            IfElse(notCondition,
+                AnonymousScope(mutableListOf(jumpLabel(loopLabel)), pos),
+                AnonymousScope(mutableListOf(), pos),
+                pos)
+        ), pos)
+        return listOf(IAstModification.ReplaceNode(untilLoop, replacement, parent))
+    }
+
+    override fun after(whileLoop: WhileLoop, parent: Node): Iterable<IAstModification> {
+        /*
+while CONDITION { STUFF }
+    ==>
+_whileloop:
+  if NOT CONDITION goto _after
+  STUFF
+  goto _whileloop
+_after:
+         */
+        val pos = whileLoop.position
+        val loopLabel = makeLabel("whileloop", pos)
+        val afterLabel = makeLabel("afterwhile", pos)
+        val notCondition = PrefixExpression("not", whileLoop.condition, pos)
+        val replacement = AnonymousScope(mutableListOf(
+            loopLabel,
+            IfElse(notCondition,
+                AnonymousScope(mutableListOf(jumpLabel(afterLabel)), pos),
+                AnonymousScope(mutableListOf(), pos),
+                pos),
+            whileLoop.body,
+            jumpLabel(loopLabel),
+            afterLabel
+        ), pos)
+        return listOf(IAstModification.ReplaceNode(whileLoop, replacement, parent))
+    }
+
+    override fun before(functionCallStatement: FunctionCallStatement, parent: Node) =
+        before(functionCallStatement as IFunctionCall, parent, functionCallStatement.position)
+
+    override fun before(functionCallExpr: FunctionCallExpression, parent: Node) =
+        before(functionCallExpr as IFunctionCall, parent, functionCallExpr.position)
+
+    private fun before(functionCall: IFunctionCall, parent: Node, position: Position): Iterable<IAstModification> {
+        if(functionCall.target.nameInSource==listOf("peek")) {
+            // peek(a) is synonymous with @(a)
+            val memread = DirectMemoryRead(functionCall.args.single(), position)
+            return listOf(IAstModification.ReplaceNode(functionCall as Node, memread, parent))
+        }
+        if(functionCall.target.nameInSource==listOf("poke")) {
+            // poke(a, v) is synonymous with @(a) = v
+            val tgt = AssignTarget(null, null, DirectMemoryWrite(functionCall.args[0], position), position)
+            val assign = Assignment(tgt, functionCall.args[1], AssignmentOrigin.OPTIMIZER, position)
+            return listOf(IAstModification.ReplaceNode(functionCall as Node, assign, parent))
+        }
+        return noModifications
+    }
+}

compiler/src/prog8/compiler/astprocessing/LiteralsToAutoVars.kt

@@ -4,6 +4,7 @@ import prog8.ast.Node
 import prog8.ast.Program
 import prog8.ast.base.DataType
 import prog8.ast.expressions.ArrayLiteralValue
+import prog8.ast.expressions.ContainmentCheck
 import prog8.ast.expressions.IdentifierReference
 import prog8.ast.expressions.StringLiteralValue
 import prog8.ast.statements.VarDecl
@@ -15,7 +16,7 @@ import prog8.ast.walk.IAstModification
 internal class LiteralsToAutoVars(private val program: Program) : AstWalker() {
 
     override fun after(string: StringLiteralValue, parent: Node): Iterable<IAstModification> {
-        if(string.parent !is VarDecl && string.parent !is WhenChoice) {
+        if(string.parent !is VarDecl && string.parent !is WhenChoice && string.parent !is ContainmentCheck) {
             // replace the literal string by an identifier reference to the interned string
             val scopedName = program.internString(string)
             val identifier = IdentifierReference(scopedName, string.position)
@@ -27,24 +28,27 @@ internal class LiteralsToAutoVars(private val program: Program) : AstWalker() {
     override fun after(array: ArrayLiteralValue, parent: Node): Iterable<IAstModification> {
         val vardecl = array.parent as? VarDecl
         if(vardecl!=null) {
-            // adjust the datatype of the array (to an educated guess)
+            // adjust the datatype of the array (to an educated guess from the vardecl type)
             val arrayDt = array.type
             if(arrayDt isnot vardecl.datatype) {
                 val cast = array.cast(vardecl.datatype)
-                if (cast != null && cast !== array)
+                if(cast!=null && cast !== array)
                     return listOf(IAstModification.ReplaceNode(vardecl.value!!, cast, vardecl))
             }
         } else {
+            if(array.parent is ContainmentCheck)
+                return noModifications
+
             val arrayDt = array.guessDatatype(program)
             if(arrayDt.isKnown) {
-                // this array literal is part of an expression, turn it into an identifier reference
+                // turn the array literal it into an identifier reference
                 val litval2 = array.cast(arrayDt.getOr(DataType.UNDEFINED))
                 if(litval2!=null) {
                     val vardecl2 = VarDecl.createAuto(litval2)
                     val identifier = IdentifierReference(listOf(vardecl2.name), vardecl2.position)
                     return listOf(
-                            IAstModification.ReplaceNode(array, identifier, parent),
-                            IAstModification.InsertFirst(vardecl2, array.definingScope)
+                        IAstModification.ReplaceNode(array, identifier, parent),
+                        IAstModification.InsertFirst(vardecl2, array.definingScope)
                     )
                 }
             }

compiler/src/prog8/compiler/astprocessing/ParentNodeChecker.kt

@@ -0,0 +1,247 @@
+package prog8.compiler.astprocessing
+
+import prog8.ast.Module
+import prog8.ast.Node
+import prog8.ast.base.FatalAstException
+import prog8.ast.expressions.*
+import prog8.ast.statements.*
+import prog8.ast.walk.AstWalker
+import prog8.ast.walk.IAstModification
+
+
+internal class ParentNodeChecker: AstWalker() {
+
+    override fun before(addressOf: AddressOf, parent: Node): Iterable<IAstModification> {
+        if(addressOf.parent!==parent)
+            throw FatalAstException("parent node mismatch at $addressOf")
+        return noModifications
+    }
+
+    override fun before(array: ArrayLiteralValue, parent: Node): Iterable<IAstModification> {
+        if(array.parent!==parent)
+            throw FatalAstException("parent node mismatch at $array")
+        return noModifications
+    }
+
+    override fun before(arrayIndexedExpression: ArrayIndexedExpression, parent: Node): Iterable<IAstModification> {
+        if(arrayIndexedExpression.parent!==parent)
+            throw FatalAstException("parent node mismatch at $arrayIndexedExpression")
+        return noModifications
+    }
+
+    override fun before(assignTarget: AssignTarget, parent: Node): Iterable<IAstModification> {
+        if(assignTarget.parent!==parent)
+            throw FatalAstException("parent node mismatch at $assignTarget")
+        return noModifications
+    }
+
+    override fun before(assignment: Assignment, parent: Node): Iterable<IAstModification> {
+        if(assignment.parent!==parent)
+            throw FatalAstException("parent node mismatch at $assignment")
+        return noModifications
+    }
+
+    override fun before(block: Block, parent: Node): Iterable<IAstModification> {
+        if(block.parent!==parent)
+            throw FatalAstException("parent node mismatch at $block")
+        return noModifications
+    }
+
+    override fun before(branch: Branch, parent: Node): Iterable<IAstModification> {
+        if(branch.parent!==parent)
+            throw FatalAstException("parent node mismatch at $branch")
+        return noModifications
+    }
+
+    override fun before(breakStmt: Break, parent: Node): Iterable<IAstModification> {
+        if(breakStmt.parent!==parent)
+            throw FatalAstException("parent node mismatch at $breakStmt")
+        return noModifications
+    }
+
+    override fun before(decl: VarDecl, parent: Node): Iterable<IAstModification> {
+        if(decl.parent!==parent)
+            throw FatalAstException("parent node mismatch at $decl")
+        return noModifications
+    }
+
+    override fun before(directive: Directive, parent: Node): Iterable<IAstModification> {
+        if(directive.parent!==parent)
+            throw FatalAstException("parent node mismatch at $directive")
+        return noModifications
+    }
+
+    override fun before(expr: BinaryExpression, parent: Node): Iterable<IAstModification> {
+        if(expr.parent!==parent)
+            throw FatalAstException("parent node mismatch at $expr")
+        return noModifications
+    }
+
+    override fun before(expr: PrefixExpression, parent: Node): Iterable<IAstModification> {
+        if(expr.parent!==parent)
+            throw FatalAstException("parent node mismatch at $expr")
+        return noModifications
+    }
+
+    override fun before(forLoop: ForLoop, parent: Node): Iterable<IAstModification> {
+        if(forLoop.parent!==parent)
+            throw FatalAstException("parent node mismatch at $forLoop")
+        return noModifications
+    }
+
+    override fun before(repeatLoop: RepeatLoop, parent: Node): Iterable<IAstModification> {
+        if(repeatLoop.parent!==parent)
+            throw FatalAstException("parent node mismatch at $repeatLoop")
+        return noModifications
+    }
+
+    override fun before(identifier: IdentifierReference, parent: Node): Iterable<IAstModification> {
+        if(identifier.parent!==parent)
+            throw FatalAstException("parent node mismatch at $identifier")
+        return noModifications
+    }
+
+    override fun before(ifElse: IfElse, parent: Node): Iterable<IAstModification> {
+        if(ifElse.parent!==parent)
+            throw FatalAstException("parent node mismatch at $ifElse")
+        return noModifications
+    }
+
+    override fun before(inlineAssembly: InlineAssembly, parent: Node): Iterable<IAstModification> {
+        if(inlineAssembly.parent!==parent)
+            throw FatalAstException("parent node mismatch at $inlineAssembly")
+        return noModifications
+    }
+
+    override fun before(jump: Jump, parent: Node): Iterable<IAstModification> {
+        if(jump.parent!==parent)
+            throw FatalAstException("parent node mismatch at $jump")
+        return noModifications
+    }
+
+    override fun before(gosub: GoSub, parent: Node): Iterable<IAstModification> {
+        if(gosub.parent!==parent)
+            throw FatalAstException("parent node mismatch at $gosub")
+        return noModifications
+    }
+
+    override fun before(label: Label, parent: Node): Iterable<IAstModification> {
+        if(label.parent!==parent)
+            throw FatalAstException("parent node mismatch at $label")
+        return noModifications
+    }
+
+    override fun before(memread: DirectMemoryRead, parent: Node): Iterable<IAstModification> {
+        if(memread.parent!==parent)
+            throw FatalAstException("parent node mismatch at $memread")
+        return noModifications
+    }
+
+    override fun before(memwrite: DirectMemoryWrite, parent: Node): Iterable<IAstModification> {
+        if(memwrite.parent!==parent)
+            throw FatalAstException("parent node mismatch at $memwrite")
+        return noModifications
+    }
+
+    override fun before(module: Module, parent: Node): Iterable<IAstModification> {
+        if(module.parent!==parent)
+            throw FatalAstException("parent node mismatch at $module")
+        return noModifications
+    }
+
+    override fun before(numLiteral: NumericLiteralValue, parent: Node): Iterable<IAstModification> {
+        if(numLiteral.parent!==parent)
+            throw FatalAstException("parent node mismatch at $numLiteral")
+        return noModifications
+    }
+
+    override fun before(postIncrDecr: PostIncrDecr, parent: Node): Iterable<IAstModification> {
+        if(postIncrDecr.parent!==parent)
+            throw FatalAstException("parent node mismatch at $postIncrDecr")
+        return noModifications
+    }
+
+    override fun before(range: RangeExpression, parent: Node): Iterable<IAstModification> {
+        if(range.parent!==parent)
+            throw FatalAstException("parent node mismatch at $range")
+        return noModifications
+    }
+
+    override fun before(untilLoop: UntilLoop, parent: Node): Iterable<IAstModification> {
+        if(untilLoop.parent!==parent)
+            throw FatalAstException("parent node mismatch at $untilLoop")
+        return noModifications
+    }
+
+    override fun before(returnStmt: Return, parent: Node): Iterable<IAstModification> {
+        if(returnStmt.parent!==parent)
+            throw FatalAstException("parent node mismatch at $returnStmt")
+        return noModifications
+    }
+
+    override fun before(char: CharLiteral, parent: Node): Iterable<IAstModification> {
+        if(char.parent!==parent)
+            throw FatalAstException("parent node mismatch at $char")
+        return noModifications
+    }
+
+    override fun before(string: StringLiteralValue, parent: Node): Iterable<IAstModification> {
+        if(string.parent!==parent)
+            throw FatalAstException("parent node mismatch at $string")
+        return noModifications
+    }
+
+    override fun before(subroutine: Subroutine, parent: Node): Iterable<IAstModification> {
+        if(subroutine.parent!==parent)
+            throw FatalAstException("parent node mismatch at $subroutine")
+        return noModifications
+    }
+
+    override fun before(typecast: TypecastExpression, parent: Node): Iterable<IAstModification> {
+        if(typecast.parent!==parent)
+            throw FatalAstException("parent node mismatch at $typecast")
+        return noModifications
+    }
+
+    override fun before(whenChoice: WhenChoice, parent: Node): Iterable<IAstModification> {
+        if(whenChoice.parent!==parent)
+            throw FatalAstException("parent node mismatch at $whenChoice")
+        return noModifications
+    }
+
+    override fun before(whenStmt: When, parent: Node): Iterable<IAstModification> {
+        if(whenStmt.parent!==parent)
+            throw FatalAstException("parent node mismatch at $whenStmt")
+        return noModifications
+    }
+
+    override fun before(whileLoop: WhileLoop, parent: Node): Iterable<IAstModification> {
+        if(whileLoop.parent!==parent)
+            throw FatalAstException("parent node mismatch at $whileLoop")
+        return noModifications
+    }
+
+    override fun before(functionCallExpr: FunctionCallExpression, parent: Node): Iterable<IAstModification> {
+        if(functionCallExpr.parent!==parent)
+            throw FatalAstException("parent node mismatch at $functionCallExpr")
+        return noModifications
+    }
+
+    override fun before(functionCallStatement: FunctionCallStatement, parent: Node): Iterable<IAstModification> {
+        if(functionCallStatement.parent!==parent)
+            throw FatalAstException("parent node mismatch at $functionCallStatement")
+        return noModifications
+    }
+
+    override fun before(nop: Nop, parent: Node): Iterable<IAstModification> {
+        if(nop.parent!==parent)
+            throw FatalAstException("parent node mismatch at $nop")
+        return noModifications
+    }
+
+    override fun before(scope: AnonymousScope, parent: Node): Iterable<IAstModification> {
+        if(scope.parent!==parent)
+            throw FatalAstException("parent node mismatch at $scope")
+        return noModifications
+    }
+}

compiler/src/prog8/compiler/astprocessing/StatementReorderer.kt

@@ -1,20 +1,18 @@
 package prog8.compiler.astprocessing
 
-import prog8.ast.IFunctionCall
-import prog8.ast.Module
-import prog8.ast.Node
-import prog8.ast.Program
-import prog8.ast.base.DataType
-import prog8.ast.base.FatalAstException
+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.compiler.IErrorReporter
-import prog8.compiler.functions.BuiltinFunctions
+import prog8.compilerinterface.BuiltinFunctions
+import prog8.compilerinterface.CompilationOptions
+import prog8.compilerinterface.IErrorReporter
 
-
-internal class StatementReorderer(val program: Program, val errors: IErrorReporter) : AstWalker() {
+internal class StatementReorderer(val program: Program,
+                                  val errors: IErrorReporter,
+                                  private val options: CompilationOptions) : AstWalker() {
     // Reorders the statements in a way the compiler needs.
     // - 'main' block must be the very first statement UNLESS it has an address set.
     // - library blocks are put last.
@@ -25,28 +23,94 @@ internal class StatementReorderer(val program: Program, val errors: IErrorReport
     // - in-place assignments are reordered a bit so that they are mostly of the form A = A <operator> <rest>
     // - sorts the choices in when statement.
     // - insert AddressOf (&) expression where required (string params to a UWORD function param etc.).
+    // - replace subroutine calls (statement) by just assigning the arguments to the parameters and then a GoSub to the routine.
 
     private val directivesToMove = setOf("%output", "%launcher", "%zeropage", "%zpreserved", "%address", "%option")
 
     override fun after(module: Module, parent: Node): Iterable<IAstModification> {
         val (blocks, other) = module.statements.partition { it is Block }
-        module.statements = other.asSequence().plus(blocks.sortedBy { (it as Block).address ?: Int.MAX_VALUE }).toMutableList()
+        module.statements = other.asSequence().plus(blocks.sortedBy { (it as Block).address ?: UInt.MAX_VALUE }).toMutableList()
 
-        val mainBlock = module.statements.filterIsInstance<Block>().firstOrNull { it.name=="main" }
+        val mainBlock = module.statements.asSequence().filterIsInstance<Block>().firstOrNull { it.name=="main" }
         if(mainBlock!=null && mainBlock.address==null) {
             module.statements.remove(mainBlock)
             module.statements.add(0, mainBlock)
         }
 
-        reorderVardeclsAndDirectives(module.statements)
+        directivesToTheTop(module.statements)
         return noModifications
     }
 
-    private fun reorderVardeclsAndDirectives(statements: MutableList<Statement>) {
-        val varDecls = statements.filterIsInstance<VarDecl>()
-        statements.removeAll(varDecls)
-        statements.addAll(0, varDecls)
+    private val declsProcessedWithInitAssignment = mutableSetOf<VarDecl>()
 
+    override fun after(decl: VarDecl, parent: Node): Iterable<IAstModification> {
+        if (decl.type == VarDeclType.VAR) {
+            if (decl.datatype in NumericDatatypes) {
+                if(decl !in declsProcessedWithInitAssignment) {
+                    declsProcessedWithInitAssignment.add(decl)
+                    if (decl.value == null) {
+                        if (decl.origin==VarDeclOrigin.USERCODE && decl.allowInitializeWithZero) {
+                            // A numeric vardecl without an initial value is initialized with zero,
+                            // unless there's already an assignment below it, that initializes the value (or a for loop that uses it as loopvar).
+                            // This allows you to restart the program and have the same starting values of the variables
+                            // So basically consider 'ubyte xx' as a short form for 'ubyte xx; xx=0'
+                            decl.value = null
+                            if(decl.name.startsWith("retval_interm_") && decl.definingScope.name=="prog8_lib") {
+                                // no need to zero out the special internal returnvalue intermediates.
+                                return noModifications
+                            }
+                            if(decl.findInitializer(program)!=null)
+                                return noModifications   // an initializer assignment for a vardecl is already here
+                            val nextFor = decl.nextSibling() as? ForLoop
+                            val hasNextForWithThisLoopvar = nextFor?.loopVar?.nameInSource==listOf(decl.name)
+                            if (!hasNextForWithThisLoopvar) {
+                                // Add assignment to initialize with zero
+                                // Note: for block-level vars, this will introduce assignments in the block scope. These have to be dealt with correctly later.
+                                val identifier = IdentifierReference(listOf(decl.name), decl.position)
+                                val assignzero = Assignment(AssignTarget(identifier, null, null, decl.position), decl.zeroElementValue(), AssignmentOrigin.VARINIT, decl.position)
+                                return listOf(IAstModification.InsertAfter(
+                                    decl, assignzero, parent as IStatementContainer
+                                ))
+                            }
+                        }
+                    } else {
+                        // Transform the vardecl with initvalue to a plain vardecl + assignment
+                        // this allows for other optimizations to kick in.
+                        // So basically consider 'ubyte xx=99' as a short form for 'ubyte xx; xx=99'
+                        val pos = decl.value!!.position
+                        val identifier = IdentifierReference(listOf(decl.name), pos)
+                        val assign = Assignment(AssignTarget(identifier, null, null, pos), decl.value!!, AssignmentOrigin.VARINIT, pos)
+                        decl.value = null
+                        return listOf(IAstModification.InsertAfter(
+                            decl, assign, parent as IStatementContainer
+                        ))
+                    }
+                }
+            }
+            else if(decl.datatype in ArrayDatatypes) {
+                // only if the initializer expression is a reference to another array, split it into a separate assignment.
+                // this is so that it later can be changed into a memcopy.
+                // (that code only triggers on regular assignment, not on variable initializers)
+                val ident = decl.value as? IdentifierReference
+                if(ident!=null) {
+                    val target = ident.targetVarDecl(program)
+                    if(target!=null && target.isArray) {
+                        val pos = decl.value!!.position
+                        val identifier = IdentifierReference(listOf(decl.name), pos)
+                        val assign = Assignment(AssignTarget(identifier, null, null, pos), decl.value!!, AssignmentOrigin.VARINIT, pos)
+                        decl.value = null
+                        return listOf(IAstModification.InsertAfter(
+                            decl, assign, parent as IStatementContainer
+                        ))
+                    }
+                }
+            }
+        }
+
+        return noModifications
+    }
+
+    private fun directivesToTheTop(statements: MutableList<Statement>) {
         val directives = statements.filterIsInstance<Directive>().filter {it.directive in directivesToMove}
         statements.removeAll(directives)
         statements.addAll(0, directives)
@@ -61,13 +125,13 @@ internal class StatementReorderer(val program: Program, val errors: IErrorReport
             )
         }
 
-        reorderVardeclsAndDirectives(block.statements)
+        directivesToTheTop(block.statements)
         return noModifications
     }
 
     override fun before(subroutine: Subroutine, parent: Node): Iterable<IAstModification> {
         if(subroutine.name=="start" && parent is Block) {
-            if(parent.statements.filterIsInstance<Subroutine>().first().name!="start") {
+            if(parent.statements.asSequence().filterIsInstance<Subroutine>().first().name!="start") {
                 return listOf(
                         IAstModification.Remove(subroutine, parent),
                         IAstModification.InsertFirst(subroutine, parent)
@@ -75,18 +139,60 @@ internal class StatementReorderer(val program: Program, val errors: IErrorReport
             }
         }
 
+        val modifications = mutableListOf<IAstModification>()
+
         val subs = subroutine.statements.filterIsInstance<Subroutine>()
         if(subs.isNotEmpty()) {
             // all subroutines defined within this subroutine are moved to the end
-            return subs.map { IAstModification.Remove(it, subroutine) } +
-                    subs.map { IAstModification.InsertLast(it, subroutine) }
+            // NOTE: this doesn't check if this has already been done!!!
+            modifications +=
+                subs.map { IAstModification.Remove(it, subroutine) } +
+                subs.map { IAstModification.InsertLast(it, subroutine) }
         }
 
-        return noModifications
+        // change 'str' and 'ubyte[]' parameters into 'uword' (just treat it as an address)
+        val stringParams = subroutine.parameters.filter { it.type==DataType.STR || it.type==DataType.ARRAY_UB }
+        val parameterChanges = stringParams.map {
+            val uwordParam = SubroutineParameter(it.name, DataType.UWORD, it.position)
+            IAstModification.ReplaceNode(it, uwordParam, subroutine)
+        }
+
+        val varsChanges = mutableListOf<IAstModification>()
+        if(!subroutine.isAsmSubroutine) {
+            val stringParamsByNames = stringParams.associateBy { it.name }
+            varsChanges +=
+                if(stringParamsByNames.isNotEmpty()) {
+                    subroutine.statements
+                        .asSequence()
+                        .filterIsInstance<VarDecl>()
+                        .filter { it.subroutineParameter!=null && it.name in stringParamsByNames }
+                        .map {
+                            val newvar = VarDecl(it.type, it.origin, DataType.UWORD,
+                                it.zeropage,
+                                null,
+                                it.name,
+                                null,
+                                false,
+                                it.sharedWithAsm,
+                                stringParamsByNames.getValue(it.name),
+                                it.position
+                            )
+                            IAstModification.ReplaceNode(it, newvar, subroutine)
+                        }
+                }
+                else emptySequence()
+        }
+
+        return modifications + parameterChanges + varsChanges
     }
 
     override fun after(arrayIndexedExpression: ArrayIndexedExpression, parent: Node): Iterable<IAstModification> {
-        return replacePointerVarIndexWithMemread(program, arrayIndexedExpression, parent)
+        if(parent !is VarDecl) {
+            // don't replace the initializer value in a vardecl - this will be moved to a separate
+            // assignment statement soon in after(VarDecl)
+            return replacePointerVarIndexWithMemreadOrMemwrite(program, arrayIndexedExpression, parent)
+        }
+        return noModifications
     }
 
     override fun after(expr: BinaryExpression, parent: Node): Iterable<IAstModification> {
@@ -94,7 +200,7 @@ internal class StatementReorderer(val program: Program, val errors: IErrorReport
         // ConstValue <associativeoperator> X -->  X <associativeoperator> ConstValue
         // (this should be done by the ExpressionSimplifier when optimizing is enabled,
         //  but the current assembly code generator for IF statements now also depends on it, so we do it here regardless of optimization.)
-        if (expr.left.constValue(program) != null && expr.operator in associativeOperators && expr.right.constValue(program) == null)
+        if (expr.left.constValue(program) != null && expr.operator in AssociativeOperators && expr.right.constValue(program) == null)
             return listOf(IAstModification.SwapOperands(expr))
 
         // when using a simple bit shift and assigning it to a variable of a different type,
@@ -122,17 +228,19 @@ internal class StatementReorderer(val program: Program, val errors: IErrorReport
                         is Subroutine -> {
                             val paramType = callee.parameters[argnum].type
                             if(leftDt isAssignableTo paramType) {
-                                val cast = TypecastExpression(expr.left, paramType, true, parent.position)
-                                return listOf(IAstModification.ReplaceNode(expr.left, cast, expr))
+                                val (replaced, cast) = expr.left.typecastTo(paramType, leftDt.getOr(DataType.UNDEFINED), true)
+                                if(replaced)
+                                    return listOf(IAstModification.ReplaceNode(expr.left, cast, expr))
                             }
                         }
-                        is BuiltinFunctionStatementPlaceholder -> {
+                        is BuiltinFunctionPlaceholder -> {
                             val func = BuiltinFunctions.getValue(callee.name)
                             val paramTypes = func.parameters[argnum].possibleDatatypes
                             for(type in paramTypes) {
                                 if(leftDt isAssignableTo type) {
-                                    val cast = TypecastExpression(expr.left, type, true, parent.position)
-                                    return listOf(IAstModification.ReplaceNode(expr.left, cast, expr))
+                                    val (replaced, cast) = expr.left.typecastTo(type, leftDt.getOr(DataType.UNDEFINED), true)
+                                    if(replaced)
+                                        return listOf(IAstModification.ReplaceNode(expr.left, cast, expr))
                                 }
                             }
                         }
@@ -142,18 +250,18 @@ internal class StatementReorderer(val program: Program, val errors: IErrorReport
                 else -> return noModifications
             }
         }
-        else if(expr.operator in logicalOperators) {
+        else if(expr.operator in LogicalOperators) {
             // make sure that logical expressions like "var and other-logical-expression
             // is rewritten as "var!=0 and other-logical-expression", to avoid bitwise boolean and
             // generating the wrong results later
 
             fun wrapped(expr: Expression): Expression =
-                BinaryExpression(expr, "!=", NumericLiteralValue(DataType.UBYTE, 0, expr.position), expr.position)
+                BinaryExpression(expr, "!=", NumericLiteralValue(DataType.UBYTE, 0.0, expr.position), expr.position)
 
             fun isLogicalExpr(expr: Expression?): Boolean {
-                if(expr is BinaryExpression && expr.operator in (logicalOperators + comparisonOperators))
+                if(expr is BinaryExpression && expr.operator in (LogicalOperators + ComparisonOperators))
                     return true
-                if(expr is PrefixExpression && expr.operator in logicalOperators)
+                if(expr is PrefixExpression && expr.operator in LogicalOperators)
                     return true
                 return false
             }
@@ -177,12 +285,19 @@ internal class StatementReorderer(val program: Program, val errors: IErrorReport
         return noModifications
     }
 
-    override fun after(whenStatement: WhenStatement, parent: Node): Iterable<IAstModification> {
-        val choices = whenStatement.choiceValues(program).sortedBy {
+    override fun after(whenStmt: When, parent: Node): Iterable<IAstModification> {
+        val lastChoiceValues = whenStmt.choices.lastOrNull()?.values
+        if(lastChoiceValues?.isNotEmpty()==true) {
+            val elseChoice = whenStmt.choices.indexOfFirst { it.values==null || it.values?.isEmpty()==true }
+            if(elseChoice>=0)
+                errors.err("else choice must be the last one", whenStmt.choices[elseChoice].position)
+        }
+
+        val choices = whenStmt.choiceValues(program).sortedBy {
             it.first?.first() ?: Int.MAX_VALUE
         }
-        whenStatement.choices.clear()
-        choices.mapTo(whenStatement.choices) { it.second }
+        whenStmt.choices.clear()
+        choices.mapTo(whenStmt.choices) { it.second }
         return noModifications
     }
 
@@ -210,7 +325,7 @@ internal class StatementReorderer(val program: Program, val errors: IErrorReport
                 return noModifications
             }
 
-            if(binExpr.operator in associativeOperators) {
+            if(binExpr.operator in AssociativeOperators) {
                 if (binExpr.right isSameAs assignment.target) {
                     // A = v <associative-operator> A  ==>  A = A <associative-operator> v
                     return listOf(IAstModification.SwapOperands(binExpr))
@@ -254,8 +369,10 @@ internal class StatementReorderer(val program: Program, val errors: IErrorReport
         val identifier = assign.target.identifier!!
         val targetVar = identifier.targetVarDecl(program)!!
 
-        if(targetVar.arraysize==null)
+        if(targetVar.arraysize==null) {
             errors.err("array has no defined size", assign.position)
+            return noModifications
+        }
 
         if(assign.value !is IdentifierReference) {
             errors.err("invalid array value to assign to other array", assign.value.position)
@@ -275,15 +392,147 @@ internal class StatementReorderer(val program: Program, val errors: IErrorReport
         if(!errors.noErrors())
             return noModifications
 
+        val numelements = targetVar.arraysize!!.constIndex()!!
+        val eltsize = program.memsizer.memorySize(ArrayToElementTypes.getValue(sourceVar.datatype))
         val memcopy = FunctionCallStatement(IdentifierReference(listOf("sys", "memcopy"), assign.position),
             mutableListOf(
                 AddressOf(sourceIdent, assign.position),
                 AddressOf(identifier, assign.position),
-                NumericLiteralValue.optimalInteger(targetVar.arraysize!!.constIndex()!!, assign.position)
+                NumericLiteralValue.optimalInteger(numelements*eltsize, assign.position)
             ),
             true,
             assign.position
         )
         return listOf(IAstModification.ReplaceNode(assign, memcopy, assign.parent))
     }
+
+    override fun after(functionCallStatement: FunctionCallStatement, parent: Node): Iterable<IAstModification> {
+        val function = functionCallStatement.target.targetStatement(program)!!
+        checkUnusedReturnValues(functionCallStatement, function, program, errors)
+        return replaceCallByGosub(functionCallStatement, parent, program, options)
+    }
+}
+
+
+internal fun replaceCallByGosub(functionCallStatement: FunctionCallStatement,
+                                parent: Node,
+                                program: Program,
+                                options: CompilationOptions): Iterable<IAstModification> {
+    val function = functionCallStatement.target.targetStatement(program)!!
+    if(function is Subroutine) {
+        if(function.inline)
+            return emptyList()
+        return if(function.isAsmSubroutine)
+            replaceCallAsmSubStatementWithGosub(function, functionCallStatement, parent, options)
+        else
+            replaceCallSubStatementWithGosub(function, functionCallStatement, parent, program)
+    }
+    return emptyList()
+}
+
+private fun replaceCallSubStatementWithGosub(function: Subroutine, call: FunctionCallStatement, parent: Node, program: Program): Iterable<IAstModification> {
+    val noModifications = emptyList<IAstModification>()
+
+    if(function.parameters.isEmpty()) {
+        // 0 params -> just GoSub
+        return listOf(IAstModification.ReplaceNode(call, GoSub(null, call.target, null, call.position), parent))
+    }
+
+    if(function.parameters.size==1) {
+        if(function.parameters[0].type in IntegerDatatypes) {
+            // optimization: 1 integer param is passed via register(s) directly, not by assignment to param variable
+            return noModifications
+        }
+    }
+    else if(function.parameters.size==2) {
+        if(function.parameters[0].type in ByteDatatypes && function.parameters[1].type in ByteDatatypes) {
+            // optimization: 2 simple byte param is passed via 2 registers directly, not by assignment to param variables
+            return noModifications
+        }
+    }
+
+    val assignParams =
+        function.parameters.zip(call.args).map {
+            var argumentValue = it.second
+            val paramIdentifier = IdentifierReference(function.scopedName + it.first.name, argumentValue.position)
+            val argDt = argumentValue.inferType(program).getOrElse { throw FatalAstException("invalid dt") }
+            if(argDt in ArrayDatatypes) {
+                // pass the address of the array instead
+                if(argumentValue is IdentifierReference)
+                    argumentValue = AddressOf(argumentValue, argumentValue.position)
+            }
+            Assignment(AssignTarget(paramIdentifier, null, null, argumentValue.position), argumentValue, AssignmentOrigin.PARAMETERASSIGN, argumentValue.position)
+        }
+    val scope = AnonymousScope(assignParams.toMutableList(), call.position)
+    scope.statements += GoSub(null, call.target, null, call.position)
+    return listOf(IAstModification.ReplaceNode(call, scope, parent))
+}
+
+private fun replaceCallAsmSubStatementWithGosub(function: Subroutine, call: FunctionCallStatement, parent: Node, options: CompilationOptions): Iterable<IAstModification> {
+    val noModifications = emptyList<IAstModification>()
+
+    if(function.parameters.isEmpty()) {
+        // 0 params -> just GoSub
+        val scope = AnonymousScope(mutableListOf(), call.position)
+        if(function.shouldSaveX()) {
+            scope.statements += FunctionCallStatement(IdentifierReference(listOf("rsavex"), call.position), mutableListOf(), true, call.position)
+        }
+        scope.statements += GoSub(null, call.target, null, call.position)
+        if(function.shouldSaveX()) {
+            scope.statements += FunctionCallStatement(IdentifierReference(listOf("rrestorex"), call.position), mutableListOf(), true, call.position)
+        }
+        return listOf(IAstModification.ReplaceNode(call, scope, parent))
+    } else if(!options.compTarget.asmsubArgsHaveRegisterClobberRisk(call.args, function.asmParameterRegisters)) {
+        // No register clobber risk, let the asmgen assign values to the registers directly.
+        // this is more efficient than first evaluating them to the stack.
+        // As complex expressions will be flagged as a clobber-risk, these will be simplified below.
+        return noModifications
+    } else {
+        // clobber risk; evaluate the arguments on the CPU stack first (in reverse order)...
+        val argOrder = options.compTarget.asmsubArgsEvalOrder(function)
+        val scope = AnonymousScope(mutableListOf(), call.position)
+        if(function.shouldSaveX()) {
+            scope.statements += FunctionCallStatement(IdentifierReference(listOf("rsavex"), call.position), mutableListOf(), true, call.position)
+        }
+        argOrder.reversed().forEach {
+            val arg = call.args[it]
+            val param = function.parameters[it]
+            scope.statements += pushCall(arg, param.type, arg.position)
+        }
+        // ... and pop them off again into the registers.
+        argOrder.forEach {
+            val param = function.parameters[it]
+            val targetName = function.scopedName + param.name
+            scope.statements += popCall(targetName, param.type, call.position)
+        }
+        scope.statements += GoSub(null, call.target, null, call.position)
+        if(function.shouldSaveX()) {
+            scope.statements += FunctionCallStatement(IdentifierReference(listOf("rrestorex"), call.position), mutableListOf(), true, call.position)
+        }
+        return listOf(IAstModification.ReplaceNode(call, scope, parent))
+    }
+}
+
+private fun popCall(targetName: List<String>, dt: DataType, position: Position): FunctionCallStatement {
+    return FunctionCallStatement(
+        IdentifierReference(listOf(if(dt in ByteDatatypes) "pop" else "popw"), position),
+        mutableListOf(IdentifierReference(targetName, position)),
+        true, position
+    )
+}
+
+private fun pushCall(value: Expression, dt: DataType, position: Position): FunctionCallStatement {
+    val pushvalue = when(dt) {
+        DataType.UBYTE, DataType.UWORD -> value
+        in PassByReferenceDatatypes -> value
+        DataType.BYTE -> TypecastExpression(value, DataType.UBYTE, true, position)
+        DataType.WORD -> TypecastExpression(value, DataType.UWORD, true, position)
+        else -> throw FatalAstException("invalid dt $dt    $value")
+    }
+
+    return FunctionCallStatement(
+        IdentifierReference(listOf(if(dt in ByteDatatypes) "push" else "pushw"), position),
+        mutableListOf(pushvalue),
+        true, position
+    )
 }

compiler/src/prog8/compiler/astprocessing/TypecastsAdder.kt

@@ -8,11 +8,12 @@ import prog8.ast.expressions.*
 import prog8.ast.statements.*
 import prog8.ast.walk.AstWalker
 import prog8.ast.walk.IAstModification
-import prog8.compiler.IErrorReporter
-import prog8.compiler.functions.BuiltinFunctions
+import prog8.compilerinterface.BuiltinFunctions
+import prog8.compilerinterface.CompilationOptions
+import prog8.compilerinterface.IErrorReporter
 
 
-class TypecastsAdder(val program: Program, val errors: IErrorReporter) : AstWalker() {
+class TypecastsAdder(val program: Program, val options: CompilationOptions, val errors: IErrorReporter) : AstWalker() {
     /*
      * Make sure any value assignments get the proper type casts if needed to cast them into the target variable's type.
      * (this includes function call arguments)
@@ -32,11 +33,9 @@ class TypecastsAdder(val program: Program, val errors: IErrorReporter) : AstWalk
                 if(valueDt isNotAssignableTo decl.datatype)
                     return noModifications
 
-                return listOf(IAstModification.ReplaceNode(
-                        declValue,
-                        TypecastExpression(declValue, decl.datatype, true, declValue.position),
-                        decl
-                ))
+                val modifications = mutableListOf<IAstModification>()
+                addTypecastOrCastedValueModification(modifications, declValue, decl.datatype, decl)
+                return modifications
             }
         }
         return noModifications
@@ -46,16 +45,59 @@ class TypecastsAdder(val program: Program, val errors: IErrorReporter) : AstWalk
         val leftDt = expr.left.inferType(program)
         val rightDt = expr.right.inferType(program)
         if(leftDt.isKnown && rightDt.isKnown && leftDt!=rightDt) {
+
+            // convert a negative operand for bitwise operator to the 2's complement positive number instead
+            if(expr.operator in BitwiseOperators && leftDt.isInteger && rightDt.isInteger) {
+                val leftCv = expr.left.constValue(program)
+                if(leftCv!=null && leftCv.number<0) {
+                    val value = if(rightDt.isBytes) 256+leftCv.number else 65536+leftCv.number
+                    return listOf(IAstModification.ReplaceNode(
+                        expr.left,
+                        NumericLiteralValue(rightDt.getOr(DataType.UNDEFINED), value, expr.left.position),
+                        expr))
+                }
+                val rightCv = expr.right.constValue(program)
+                if(rightCv!=null && rightCv.number<0) {
+                    val value = if(leftDt.isBytes) 256+rightCv.number else 65536+rightCv.number
+                    return listOf(IAstModification.ReplaceNode(
+                        expr.right,
+                        NumericLiteralValue(leftDt.getOr(DataType.UNDEFINED), value, expr.right.position),
+                        expr))
+                }
+
+                if(leftDt istype DataType.BYTE && rightDt.oneOf(DataType.UBYTE, DataType.UWORD)) {
+                    // cast left to unsigned
+                    val cast = TypecastExpression(expr.left, rightDt.getOr(DataType.UNDEFINED), true, expr.left.position)
+                    return listOf(IAstModification.ReplaceNode(expr.left, cast, expr))
+                }
+                if(leftDt istype DataType.WORD && rightDt.oneOf(DataType.UBYTE, DataType.UWORD)) {
+                    // cast left to unsigned
+                    val cast = TypecastExpression(expr.left, rightDt.getOr(DataType.UNDEFINED), true, expr.left.position)
+                    return listOf(IAstModification.ReplaceNode(expr.left, cast, expr))
+                }
+                if(rightDt istype DataType.BYTE && leftDt.oneOf(DataType.UBYTE, DataType.UWORD)) {
+                    // cast right to unsigned
+                    val cast = TypecastExpression(expr.right, leftDt.getOr(DataType.UNDEFINED), true, expr.right.position)
+                    return listOf(IAstModification.ReplaceNode(expr.right, cast, expr))
+                }
+                if(rightDt istype DataType.WORD && leftDt.oneOf(DataType.UBYTE, DataType.UWORD)) {
+                    // cast right to unsigned
+                    val cast = TypecastExpression(expr.right, leftDt.getOr(DataType.UNDEFINED), true, expr.right.position)
+                    return listOf(IAstModification.ReplaceNode(expr.right, cast, expr))
+                }
+            }
+
+
             // determine common datatype and add typecast as required to make left and right equal types
             val (commonDt, toFix) = BinaryExpression.commonDatatype(leftDt.getOr(DataType.UNDEFINED), rightDt.getOr(DataType.UNDEFINED), expr.left, expr.right)
             if(toFix!=null) {
-                return when {
-                    toFix===expr.left -> listOf(IAstModification.ReplaceNode(
-                            expr.left, TypecastExpression(expr.left, commonDt, true, expr.left.position), expr))
-                    toFix===expr.right -> listOf(IAstModification.ReplaceNode(
-                            expr.right, TypecastExpression(expr.right, commonDt, true, expr.right.position), expr))
+                val modifications = mutableListOf<IAstModification>()
+                when {
+                    toFix===expr.left -> addTypecastOrCastedValueModification(modifications, expr.left, commonDt, expr)
+                    toFix===expr.right -> addTypecastOrCastedValueModification(modifications, expr.right, commonDt, expr)
                     else -> throw FatalAstException("confused binary expression side")
                 }
+                return modifications
             }
         }
         return noModifications
@@ -73,21 +115,20 @@ class TypecastsAdder(val program: Program, val errors: IErrorReporter) : AstWalk
                     if(valuetype in IterableDatatypes && targettype==DataType.UWORD)
                         // special case, don't typecast STR/arrays to UWORD, we support those assignments "directly"
                         return noModifications
-                    return listOf(IAstModification.ReplaceNode(
-                            assignment.value,
-                            TypecastExpression(assignment.value, targettype, true, assignment.value.position),
-                            assignment))
+                    val modifications = mutableListOf<IAstModification>()
+                    addTypecastOrCastedValueModification(modifications, assignment.value, targettype, assignment)
+                    return modifications
                 } else {
-                    fun castLiteral(cvalue: NumericLiteralValue): List<IAstModification.ReplaceNode> {
-                        val cast = cvalue.cast(targettype)
+                    fun castLiteral(cvalue2: NumericLiteralValue): List<IAstModification.ReplaceNode> {
+                        val cast = cvalue2.cast(targettype)
                         return if(cast.isValid)
-                            listOf(IAstModification.ReplaceNode(cvalue, cast.valueOrZero(), cvalue.parent))
+                            listOf(IAstModification.ReplaceNode(assignment.value, cast.valueOrZero(), assignment))
                         else
                             emptyList()
                     }
                     val cvalue = assignment.value.constValue(program)
                     if(cvalue!=null) {
-                        val number = cvalue.number.toDouble()
+                        val number = cvalue.number
                         // more complex comparisons if the type is different, but the constant value is compatible
                         if (valuetype == DataType.BYTE && targettype == DataType.UBYTE) {
                             if(number>0)
@@ -113,8 +154,8 @@ class TypecastsAdder(val program: Program, val errors: IErrorReporter) : AstWalk
         return afterFunctionCallArgs(functionCallStatement)
     }
 
-    override fun after(functionCall: FunctionCall, parent: Node): Iterable<IAstModification> {
-        return afterFunctionCallArgs(functionCall)
+    override fun after(functionCallExpr: FunctionCallExpression, parent: Node): Iterable<IAstModification> {
+        return afterFunctionCallArgs(functionCallExpr)
     }
 
     private fun afterFunctionCallArgs(call: IFunctionCall): Iterable<IAstModification> {
@@ -130,23 +171,24 @@ class TypecastsAdder(val program: Program, val errors: IErrorReporter) : AstWalk
                         val requiredType = pair.first.type
                         if (requiredType != argtype) {
                             if (argtype isAssignableTo requiredType) {
-                                modifications += IAstModification.ReplaceNode(
-                                        call.args[index],
-                                        TypecastExpression(pair.second, requiredType, true, pair.second.position),
-                                        call as Node)
+                                // don't need a cast for pass-by-reference types that are assigned to UWORD
+                                if(requiredType!=DataType.UWORD || argtype !in PassByReferenceDatatypes)
+                                    addTypecastOrCastedValueModification(modifications, pair.second, requiredType, call as Node)
                             } else if(requiredType == DataType.UWORD && argtype in PassByReferenceDatatypes) {
-                                // we allow STR/ARRAY values in place of UWORD parameters. Take their address instead.
-                                if(pair.second is IdentifierReference) {
+                                // We allow STR/ARRAY values in place of UWORD parameters.
+                                // Take their address instead, UNLESS it's a str parameter in the containing subroutine
+                                val identifier = pair.second as? IdentifierReference
+                                if(identifier?.isSubroutineParameter(program)==false) {
                                     modifications += IAstModification.ReplaceNode(
-                                            call.args[index],
-                                            AddressOf(pair.second as IdentifierReference, pair.second.position),
+                                            identifier,
+                                            AddressOf(identifier, pair.second.position),
                                             call as Node)
                                 }
                             } else if(pair.second is NumericLiteralValue) {
                                 val cast = (pair.second as NumericLiteralValue).cast(requiredType)
                                 if(cast.isValid)
                                     modifications += IAstModification.ReplaceNode(
-                                            call.args[index],
+                                            pair.second,
                                             cast.valueOrZero(),
                                             call as Node)
                             }
@@ -154,7 +196,7 @@ class TypecastsAdder(val program: Program, val errors: IErrorReporter) : AstWalk
                     }
                 }
             }
-            is BuiltinFunctionStatementPlaceholder -> {
+            is BuiltinFunctionPlaceholder -> {
                 val func = BuiltinFunctions.getValue(sub.name)
                 func.parameters.zip(call.args).forEachIndexed { index, pair ->
                     val argItype = pair.second.inferType(program)
@@ -163,12 +205,21 @@ class TypecastsAdder(val program: Program, val errors: IErrorReporter) : AstWalk
                         if (pair.first.possibleDatatypes.all { argtype != it }) {
                             for (possibleType in pair.first.possibleDatatypes) {
                                 if (argtype isAssignableTo possibleType) {
-                                    modifications += IAstModification.ReplaceNode(
-                                            call.args[index],
-                                            TypecastExpression(pair.second, possibleType, true, pair.second.position),
-                                            call as Node)
+                                    addTypecastOrCastedValueModification(modifications, pair.second, possibleType, call as Node)
                                     break
                                 }
+                                else if(DataType.UWORD in pair.first.possibleDatatypes && argtype in PassByReferenceDatatypes) {
+                                    // We allow STR/ARRAY values in place of UWORD parameters.
+                                    // Take their address instead, UNLESS it's a str parameter in the containing subroutine
+                                    val identifier = pair.second as? IdentifierReference
+                                    if(identifier?.isSubroutineParameter(program)==false) {
+                                        modifications += IAstModification.ReplaceNode(
+                                            call.args[index],
+                                            AddressOf(identifier, pair.second.position),
+                                            call as Node)
+                                        break
+                                    }
+                                }
                             }
                         }
                     }
@@ -183,31 +234,41 @@ class TypecastsAdder(val program: Program, val errors: IErrorReporter) : AstWalk
     override fun after(typecast: TypecastExpression, parent: Node): Iterable<IAstModification> {
         // warn about any implicit type casts to Float, because that may not be intended
         if(typecast.implicit && typecast.type.oneOf(DataType.FLOAT, DataType.ARRAY_F)) {
-            errors.warn("integer implicitly converted to float. Suggestion: use float literals, add an explicit cast, or revert to integer arithmetic", typecast.position)
+            if(options.floats)
+                errors.warn("integer implicitly converted to float. Suggestion: use float literals, add an explicit cast, or revert to integer arithmetic", typecast.position)
+            else
+                errors.err("integer implicitly converted to float but floating point is not enabled via options", typecast.position)
         }
+
         return noModifications
     }
 
     override fun after(memread: DirectMemoryRead, parent: Node): Iterable<IAstModification> {
         // make sure the memory address is an uword
+        val modifications = mutableListOf<IAstModification>()
         val dt = memread.addressExpression.inferType(program)
         if(dt.isKnown && dt.getOr(DataType.UWORD)!=DataType.UWORD) {
-            val typecast = (memread.addressExpression as? NumericLiteralValue)?.cast(DataType.UWORD)?.valueOrZero()
-                    ?: TypecastExpression(memread.addressExpression, DataType.UWORD, true, memread.addressExpression.position)
-            return listOf(IAstModification.ReplaceNode(memread.addressExpression, typecast, memread))
+            val castedValue = (memread.addressExpression as? NumericLiteralValue)?.cast(DataType.UWORD)?.valueOrZero()
+            if(castedValue!=null)
+                modifications += IAstModification.ReplaceNode(memread.addressExpression, castedValue, memread)
+            else
+                addTypecastOrCastedValueModification(modifications, memread.addressExpression, DataType.UWORD, memread)
         }
-        return noModifications
+        return modifications
     }
 
     override fun after(memwrite: DirectMemoryWrite, parent: Node): Iterable<IAstModification> {
         // make sure the memory address is an uword
+        val modifications = mutableListOf<IAstModification>()
         val dt = memwrite.addressExpression.inferType(program)
         if(dt.isKnown && dt.getOr(DataType.UWORD)!=DataType.UWORD) {
-            val typecast = (memwrite.addressExpression as? NumericLiteralValue)?.cast(DataType.UWORD)?.valueOrZero()
-                    ?: TypecastExpression(memwrite.addressExpression, DataType.UWORD, true, memwrite.addressExpression.position)
-            return listOf(IAstModification.ReplaceNode(memwrite.addressExpression, typecast, memwrite))
+            val castedValue = (memwrite.addressExpression as? NumericLiteralValue)?.cast(DataType.UWORD)?.valueOrZero()
+            if(castedValue!=null)
+                modifications += IAstModification.ReplaceNode(memwrite.addressExpression, castedValue, memwrite)
+            else
+                addTypecastOrCastedValueModification(modifications, memwrite.addressExpression, DataType.UWORD, memwrite)
         }
-        return noModifications
+        return modifications
     }
 
     override fun after(returnStmt: Return, parent: Node): Iterable<IAstModification> {
@@ -224,13 +285,32 @@ class TypecastsAdder(val program: Program, val errors: IErrorReporter) : AstWalk
                     if(cast.isValid)
                         returnStmt.value = cast.valueOrZero()
                 } else {
-                    return listOf(IAstModification.ReplaceNode(
-                            returnValue,
-                            TypecastExpression(returnValue, subReturnType, true, returnValue.position),
-                            returnStmt))
+                    val modifications = mutableListOf<IAstModification>()
+                    addTypecastOrCastedValueModification(modifications, returnValue, subReturnType, returnStmt)
+                    return modifications
                 }
             }
         }
         return noModifications
     }
+
+    private fun addTypecastOrCastedValueModification(
+        modifications: MutableList<IAstModification>,
+        expressionToCast: Expression,
+        requiredType: DataType,
+        parent: Node
+    ) {
+        val sourceDt = expressionToCast.inferType(program).getOr(DataType.UNDEFINED)
+        if(sourceDt == requiredType)
+            return
+        if(expressionToCast is NumericLiteralValue && expressionToCast.type!=DataType.FLOAT) { // refuse to automatically truncate floats
+            val castedValue = expressionToCast.cast(requiredType)
+            if (castedValue.isValid) {
+                modifications += IAstModification.ReplaceNode(expressionToCast, castedValue.valueOrZero(), parent)
+                return
+            }
+        }
+        val cast = TypecastExpression(expressionToCast, requiredType, true, expressionToCast.position)
+        modifications += IAstModification.ReplaceNode(expressionToCast, cast, parent)
+    }
 }

compiler/src/prog8/compiler/astprocessing/VariousCleanups.kt

@@ -1,32 +1,34 @@
 package prog8.compiler.astprocessing
 
 import prog8.ast.IFunctionCall
-import prog8.ast.INameScope
+import prog8.ast.IStatementContainer
 import prog8.ast.Node
 import prog8.ast.Program
+import prog8.ast.base.ArrayDatatypes
+import prog8.ast.base.DataType
 import prog8.ast.base.FatalAstException
-import prog8.ast.base.Position
 import prog8.ast.expressions.*
 import prog8.ast.statements.*
 import prog8.ast.walk.AstWalker
 import prog8.ast.walk.IAstModification
-import prog8.compiler.IErrorReporter
+import prog8.compilerinterface.CompilationOptions
+import prog8.compilerinterface.IErrorReporter
 
 
-internal class VariousCleanups(val program: Program, val errors: IErrorReporter): AstWalker() {
+internal class VariousCleanups(val program: Program, val errors: IErrorReporter, val options: CompilationOptions): AstWalker() {
 
-    override fun before(nopStatement: NopStatement, parent: Node): Iterable<IAstModification> {
-        return listOf(IAstModification.Remove(nopStatement, parent as INameScope))
+    override fun before(nop: Nop, parent: Node): Iterable<IAstModification> {
+        return listOf(IAstModification.Remove(nop, parent as IStatementContainer))
     }
 
-    override fun before(scope: AnonymousScope, parent: Node): Iterable<IAstModification> {
-        return if(parent is INameScope)
-            listOf(ScopeFlatten(scope, parent as INameScope))
+    override fun after(scope: AnonymousScope, parent: Node): Iterable<IAstModification> {
+        return if(parent is IStatementContainer)
+            listOf(ScopeFlatten(scope, parent as IStatementContainer))
         else
             noModifications
     }
 
-    class ScopeFlatten(val scope: AnonymousScope, val into: INameScope) : IAstModification {
+    private class ScopeFlatten(val scope: AnonymousScope, val into: IStatementContainer) : IAstModification {
         override fun perform() {
             val idx = into.statements.indexOf(scope)
             if(idx>=0) {
@@ -37,33 +39,7 @@ internal class VariousCleanups(val program: Program, val errors: IErrorReporter)
         }
     }
 
-    override fun before(functionCallStatement: FunctionCallStatement, parent: Node): Iterable<IAstModification> {
-        return before(functionCallStatement as IFunctionCall, parent, functionCallStatement.position)
-    }
-
-    override fun before(functionCall: FunctionCall, parent: Node): Iterable<IAstModification> {
-        return before(functionCall as IFunctionCall, parent, functionCall.position)
-    }
-
-    private fun before(functionCall: IFunctionCall, parent: Node, position: Position): Iterable<IAstModification> {
-        if(functionCall.target.nameInSource==listOf("peek")) {
-            // peek(a) is synonymous with @(a)
-            val memread = DirectMemoryRead(functionCall.args.single(), position)
-            return listOf(IAstModification.ReplaceNode(functionCall as Node, memread, parent))
-        }
-        if(functionCall.target.nameInSource==listOf("poke")) {
-            // poke(a, v) is synonymous with @(a) = v
-            val tgt = AssignTarget(null, null, DirectMemoryWrite(functionCall.args[0], position), position)
-            val assign = Assignment(tgt, functionCall.args[1], position)
-            return listOf(IAstModification.ReplaceNode(functionCall as Node, assign, parent))
-        }
-        return noModifications
-    }
-
     override fun after(typecast: TypecastExpression, parent: Node): Iterable<IAstModification> {
-        if(typecast.parent!==parent)
-            throw FatalAstException("parent node mismatch at $typecast")
-
         if(typecast.expression is NumericLiteralValue) {
             val value = (typecast.expression as NumericLiteralValue).cast(typecast.type)
             if(value.isValid)
@@ -74,48 +50,159 @@ internal class VariousCleanups(val program: Program, val errors: IErrorReporter)
         if(sourceDt istype typecast.type)
             return listOf(IAstModification.ReplaceNode(typecast, typecast.expression, parent))
 
-        return noModifications
-    }
+        if(parent is Assignment) {
+            val targetDt = (parent).target.inferType(program).getOrElse { throw FatalAstException("invalid dt") }
+            if(sourceDt istype targetDt) {
+                // we can get rid of this typecast because the type is already
+                return listOf(IAstModification.ReplaceNode(typecast, typecast.expression, parent))
+            }
+        }
 
-    override fun after(subroutine: Subroutine, parent: Node): Iterable<IAstModification> {
-        if(subroutine.parent!==parent)
-            throw FatalAstException("parent node mismatch at $subroutine")
         return noModifications
     }
 
     override fun after(assignment: Assignment, parent: Node): Iterable<IAstModification> {
-        if(assignment.parent!==parent)
-            throw FatalAstException("parent node mismatch at $assignment")
+        val nextAssign = assignment.nextSibling() as? Assignment
+        if(nextAssign!=null && nextAssign.target.isSameAs(assignment.target, program)) {
+            if(nextAssign.value isSameAs assignment.value && assignment.value !is IFunctionCall)    // don't remove function calls even when they're duplicates
+                return listOf(IAstModification.Remove(assignment, parent as IStatementContainer))
+        }
+
         return noModifications
     }
 
-    override fun after(assignTarget: AssignTarget, parent: Node): Iterable<IAstModification> {
-        if(assignTarget.parent!==parent)
-            throw FatalAstException("parent node mismatch at $assignTarget")
+    override fun after(expr: PrefixExpression, parent: Node): Iterable<IAstModification> {
+        if(expr.operator=="+") {
+            // +X --> X
+            return listOf(IAstModification.ReplaceNode(expr, expr.expression, parent))
+        }
+        if(expr.operator=="not") {
+            val nestedPrefix = expr.expression as? PrefixExpression
+            if(nestedPrefix!=null && nestedPrefix.operator=="not") {
+                // NOT NOT X  -->  X
+                return listOf(IAstModification.ReplaceNode(expr, nestedPrefix.expression, parent))
+            }
+            val comparison = expr.expression as? BinaryExpression
+            if (comparison != null) {
+                // NOT COMPARISON ==> inverted COMPARISON
+                val invertedOperator = invertedComparisonOperator(comparison.operator)
+                if (invertedOperator != null) {
+                    comparison.operator = invertedOperator
+                    return listOf(IAstModification.ReplaceNode(expr, comparison, parent))
+                }
+            }
+        }
         return noModifications
     }
 
-    override fun after(decl: VarDecl, parent: Node): Iterable<IAstModification> {
-        if(decl.parent!==parent)
-            throw FatalAstException("parent node mismatch at $decl")
+    override fun before(expr: BinaryExpression, parent: Node): Iterable<IAstModification> {
+        if(expr.operator == "or") {
+            val leftBinExpr = expr.left as? BinaryExpression
+            val rightBinExpr = expr.right as? BinaryExpression
+            if(leftBinExpr!=null && leftBinExpr.operator=="==" && rightBinExpr!=null && rightBinExpr.operator=="==") {
+                if(leftBinExpr.right is NumericLiteralValue && rightBinExpr.right is NumericLiteralValue) {
+                    if(leftBinExpr.left isSameAs rightBinExpr.left)
+                        errors.warn("consider using 'in' or 'when' to test for multiple values", expr.position)
+                }
+            }
+        }
         return noModifications
     }
 
-    override fun after(scope: AnonymousScope, parent: Node): Iterable<IAstModification> {
-        if(scope.parent!==parent)
-            throw FatalAstException("parent node mismatch at $scope")
+    override fun after(expr: BinaryExpression, parent: Node): Iterable<IAstModification> {
+        if(expr.operator in ComparisonOperators) {
+            val leftConstVal = expr.left.constValue(program)
+            val rightConstVal = expr.right.constValue(program)
+            // make sure the constant value is on the right of the comparison expression
+            if(rightConstVal==null && leftConstVal!=null) {
+                val newOperator =
+                    when(expr.operator) {
+                        "<" -> ">"
+                        "<=" -> ">="
+                        ">" -> "<"
+                        ">=" -> "<="
+                        else -> expr.operator
+                    }
+                val replacement = BinaryExpression(expr.right, newOperator, expr.left, expr.position)
+                return listOf(IAstModification.ReplaceNode(expr, replacement, parent))
+            }
+        }
         return noModifications
     }
 
-    override fun after(returnStmt: Return, parent: Node): Iterable<IAstModification> {
-        if(returnStmt.parent!==parent)
-            throw FatalAstException("parent node mismatch at $returnStmt")
+    override fun after(containment: ContainmentCheck, parent: Node): Iterable<IAstModification> {
+        // replace trivial containment checks with just false or a single comparison
+        fun replaceWithEquals(value: NumericLiteralValue): Iterable<IAstModification> {
+            errors.warn("containment could be written as just a single comparison", containment.position)
+            val equals = BinaryExpression(containment.element, "==", value, containment.position)
+            return listOf(IAstModification.ReplaceNode(containment, equals, parent))
+        }
+
+        fun replaceWithFalse(): Iterable<IAstModification> {
+            errors.warn("condition is always false", containment.position)
+            return listOf(IAstModification.ReplaceNode(containment, NumericLiteralValue.fromBoolean(false, containment.position), parent))
+        }
+
+        fun checkArray(array: Array<Expression>): Iterable<IAstModification> {
+            if(array.isEmpty())
+                return replaceWithFalse()
+            if(array.size==1) {
+                val constVal = array[0].constValue(program)
+                if(constVal!=null)
+                    return replaceWithEquals(constVal)
+            }
+            return noModifications
+        }
+
+        fun checkString(stringVal: StringLiteralValue): Iterable<IAstModification> {
+            if(stringVal.value.isEmpty())
+                return replaceWithFalse()
+            if(stringVal.value.length==1) {
+                val string = program.encoding.encodeString(stringVal.value, stringVal.encoding)
+                return replaceWithEquals(NumericLiteralValue(DataType.UBYTE, string[0].toDouble(), stringVal.position))
+            }
+            return noModifications
+        }
+
+        when(containment.iterable) {
+            is ArrayLiteralValue -> {
+                val array = (containment.iterable as ArrayLiteralValue).value
+                return checkArray(array)
+            }
+            is IdentifierReference -> {
+                val variable = (containment.iterable as IdentifierReference).targetVarDecl(program)!!
+                when(variable.datatype) {
+                    DataType.STR -> {
+                        val stringVal = (variable.value as StringLiteralValue)
+                        return checkString(stringVal)
+                    }
+                    in ArrayDatatypes -> {
+                        val array = (variable.value as ArrayLiteralValue).value
+                        return checkArray(array)
+                    }
+                    else -> {}
+                }
+            }
+            is RangeExpression -> {
+                val constValues = (containment.iterable as RangeExpression).toConstantIntegerRange()
+                if(constValues!=null) {
+                    if (constValues.isEmpty())
+                        return replaceWithFalse()
+                    if (constValues.count()==1)
+                        return replaceWithEquals(NumericLiteralValue.optimalNumeric(constValues.first, containment.position))
+                }
+            }
+            is StringLiteralValue -> {
+                val stringVal = containment.iterable as StringLiteralValue
+                return checkString(stringVal)
+            }
+            else -> {}
+        }
         return noModifications
     }
 
-    override fun after(identifier: IdentifierReference, parent: Node): Iterable<IAstModification> {
-        if(identifier.parent!==parent)
-            throw FatalAstException("parent node mismatch at $identifier")
-        return noModifications
+    override fun after(functionCallStatement: FunctionCallStatement, parent: Node): Iterable<IAstModification> {
+        return replaceCallByGosub(functionCallStatement, parent, program, options)
     }
 }
+

compiler/src/prog8/compiler/astprocessing/VerifyFunctionArgTypes.kt

@@ -4,25 +4,25 @@ import prog8.ast.IFunctionCall
 import prog8.ast.Program
 import prog8.ast.base.DataType
 import prog8.ast.expressions.Expression
-import prog8.ast.expressions.FunctionCall
+import prog8.ast.expressions.FunctionCallExpression
 import prog8.ast.expressions.TypecastExpression
 import prog8.ast.statements.*
 import prog8.ast.walk.IAstVisitor
-import prog8.compiler.CompilerException
-import prog8.compiler.functions.BuiltinFunctions
+import prog8.compilerinterface.BuiltinFunctions
+import prog8.compilerinterface.InternalCompilerException
 
-class VerifyFunctionArgTypes(val program: Program) : IAstVisitor {
+internal class VerifyFunctionArgTypes(val program: Program) : IAstVisitor {
 
-    override fun visit(functionCall: FunctionCall) {
-        val error = checkTypes(functionCall as IFunctionCall, program)
+    override fun visit(functionCallExpr: FunctionCallExpression) {
+        val error = checkTypes(functionCallExpr as IFunctionCall, program)
         if(error!=null)
-            throw CompilerException(error)
+            throw InternalCompilerException(error)
     }
 
     override fun visit(functionCallStatement: FunctionCallStatement) {
         val error = checkTypes(functionCallStatement as IFunctionCall, program)
         if (error!=null)
-            throw CompilerException(error)
+            throw InternalCompilerException(error)
     }
 
     companion object {
@@ -33,7 +33,9 @@ class VerifyFunctionArgTypes(val program: Program) : IAstVisitor {
 
             // there are some exceptions that are considered compatible, such as STR <> UWORD
             if(argDt==DataType.STR && paramDt==DataType.UWORD ||
-                    argDt==DataType.UWORD && paramDt==DataType.STR)
+                    argDt==DataType.UWORD && paramDt==DataType.STR ||
+                    argDt==DataType.UWORD && paramDt==DataType.ARRAY_UB ||
+                    argDt==DataType.STR && paramDt==DataType.ARRAY_UB)
                 return true
 
             return false
@@ -74,7 +76,7 @@ class VerifyFunctionArgTypes(val program: Program) : IAstVisitor {
                     }
                 }
             }
-            else if (target is BuiltinFunctionStatementPlaceholder) {
+            else if (target is BuiltinFunctionPlaceholder) {
                 val func = BuiltinFunctions.getValue(target.name)
                 if(call.args.size != func.parameters.size)
                     return "invalid number of arguments"
@@ -83,8 +85,13 @@ class VerifyFunctionArgTypes(val program: Program) : IAstVisitor {
                     val anyCompatible = pair.second.any { argTypeCompatible(pair.first, it) }
                     if (!anyCompatible) {
                         val actual = pair.first.toString()
-                        val expected = pair.second.toString()
-                        return "argument ${index + 1} type mismatch, was: $actual expected: $expected"
+                        return if(pair.second.size==1) {
+                            val expected = pair.second[0].toString()
+                            "argument ${index + 1} type mismatch, was: $actual expected: $expected"
+                        } else {
+                            val expected = pair.second.toList().toString()
+                            "argument ${index + 1} type mismatch, was: $actual expected one of: $expected"
+                        }
                     }
                 }
             }