attempt to fix ReadTheDocs build issue

# Conflicts:
#	compiler/res/version.txt

.gitignore

@@ -26,6 +26,7 @@ parser.out
 parsetab.py
 .pytest_cache/
 .attach_pid*
+compiler/lib/
 
 .gradle
 /prog8compiler.jar

.idea/codeInsightSettings.xml

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

.idea/compiler.xml

@@ -2,5 +2,6 @@
 <project version="4">
   <component name="CompilerConfiguration">
     <option name="BUILD_PROCESS_HEAP_SIZE" value="1200" />
+    <bytecodeTargetLevel target="11" />
   </component>
-</project>
+</project>

.idea/kotlinc.xml

@@ -1,6 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<project version="4">
-  <component name="Kotlin2JvmCompilerArguments">
-    <option name="jvmTarget" value="11" />
-  </component>
-</project>

.idea/libraries/antlr_4_9_complete.xml

@@ -1,9 +0,0 @@
-<component name="libraryTable">
-  <library name="antlr-4.9-complete">
-    <CLASSES>
-      <root url="jar://$PROJECT_DIR$/parser/antlr/lib/antlr-4.9.2-complete.jar!/" />
-    </CLASSES>
-    <JAVADOC />
-    <SOURCES />
-  </library>
-</component>

.idea/libraries/antlr_antlr4.xml

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

.idea/libraries/antlr_runtime_4_9.xml

@@ -1,9 +0,0 @@
-<component name="libraryTable">
-  <library name="antlr-runtime-4.9">
-    <CLASSES>
-      <root url="jar://$PROJECT_DIR$/parser/antlr/lib/antlr-runtime-4.9.2.jar!/" />
-    </CLASSES>
-    <JAVADOC />
-    <SOURCES />
-  </library>
-</component>

.idea/libraries/dbus_java_3_2_4.xml

@@ -1,9 +0,0 @@
-<component name="libraryTable">
-  <library name="dbus-java-3.2.4">
-    <CLASSES>
-      <root url="jar://$PROJECT_DIR$/dbusCompilerService/lib/dbus-java-3.2.4.jar!/" />
-    </CLASSES>
-    <JAVADOC />
-    <SOURCES />
-  </library>
-</component>

.idea/libraries/github_hypfvieh_dbus_java.xml

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

.idea/libraries/glassfish_javax_json.xml

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

.idea/libraries/hamcrest.xml

@@ -0,0 +1,10 @@
+<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/javax_json_api_1_1_4.xml

@@ -1,10 +0,0 @@
-<component name="libraryTable">
-  <library name="javax.json-api-1.1.4">
-    <CLASSES>
-      <root url="jar://$PROJECT_DIR$/httpCompilerService/lib/javax.json-api-1.1.4.jar!/" />
-      <root url="jar://$PROJECT_DIR$/httpCompilerService/lib/javax.json-1.1.4.jar!/" />
-    </CLASSES>
-    <JAVADOC />
-    <SOURCES />
-  </library>
-</component>

.idea/libraries/jetbrains_kotlinx_cli_jvm.xml

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

.idea/libraries/junit_jupiter.xml

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

.idea/libraries/kotlinx_cli_jvm.xml

@@ -1,9 +0,0 @@
-<component name="libraryTable">
-  <library name="kotlinx-cli-jvm">
-    <CLASSES>
-      <root url="jar://$PROJECT_DIR$/compiler/lib/kotlinx-cli-jvm-0.3.2.jar!/" />
-    </CLASSES>
-    <JAVADOC />
-    <SOURCES />
-  </library>
-</component>

.idea/libraries/michael_bull_kotlin_result_jvm.xml

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

.idea/libraries/slf4j_api_1_7_30.xml

@@ -1,10 +0,0 @@
-<component name="libraryTable">
-  <library name="slf4j-api-1.7.30">
-    <CLASSES>
-      <root url="jar://$PROJECT_DIR$/httpCompilerService/lib/slf4j-api-1.7.30.jar!/" />
-      <root url="jar://$PROJECT_DIR$/httpCompilerService/lib/slf4j-simple-1.7.30.jar!/" />
-    </CLASSES>
-    <JAVADOC />
-    <SOURCES />
-  </library>
-</component>

.idea/libraries/slf4j_simple.xml

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

.idea/libraries/takes.xml

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

.idea/libraries/takes_http.xml

@@ -1,12 +0,0 @@
-<component name="libraryTable">
-  <library name="takes-http">
-    <CLASSES>
-      <root url="jar://$PROJECT_DIR$/httpCompilerService/lib/cactoos-0.42.jar!/" />
-      <root url="jar://$PROJECT_DIR$/httpCompilerService/lib/commons-lang3-3.7.jar!/" />
-      <root url="jar://$PROJECT_DIR$/httpCompilerService/lib/commons-text-1.4.jar!/" />
-      <root url="jar://$PROJECT_DIR$/httpCompilerService/lib/takes-1.19.jar!/" />
-    </CLASSES>
-    <JAVADOC />
-    <SOURCES />
-  </library>
-</component>

.idea/libraries/unittest_libs.xml

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

.idea/misc.xml

@@ -4,7 +4,7 @@
     <option name="perGrammarGenerationSettings">
       <list>
         <PerGrammarGenerationSettings>
-          <option name="fileName" value="$PROJECT_DIR$/parser/antlr/prog8.g4" />
+          <option name="fileName" value="$PROJECT_DIR$/parser/antlr/Prog8ANTLR.g4" />
           <option name="autoGen" value="true" />
           <option name="outputDir" value="$PROJECT_DIR$/parser/src/prog8/parser" />
           <option name="libDir" value="" />
@@ -16,7 +16,7 @@
       </list>
     </option>
   </component>
-  <component name="ProjectRootManager" version="2" languageLevel="JDK_11" default="false" project-jdk-name="Kotlin SDK" project-jdk-type="KotlinSDK">
+  <component name="ProjectRootManager" version="2" languageLevel="JDK_11" project-jdk-name="Kotlin SDK" project-jdk-type="KotlinSDK">
     <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

.travis.yml

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

CompilerDevelopment.md

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

README.md

@@ -1,5 +1,3 @@
-[![saythanks](https://img.shields.io/badge/say-thanks-ff69b4.svg)](https://saythanks.io/to/irmen)
-[![Build Status](https://travis-ci.org/irmen/prog8.svg?branch=master)](https://travis-ci.org/irmen/prog8)
 [![Documentation](https://readthedocs.org/projects/prog8/badge/?version=latest)](https://prog8.readthedocs.io/)
 
 Prog8 - Structured Programming Language for 8-bit 6502/65c02 microprocessors

build.gradle

@@ -1,3 +1,10 @@
 plugins {
-    id "org.jetbrains.kotlin.jvm" version "1.5.20" apply false
+    id "org.jetbrains.kotlin.jvm" version "$kotlinVersion" apply false
+}
+
+allprojects {
+    repositories {
+        mavenLocal()
+        mavenCentral()
+    }
 }

codeGeneration/build.gradle

@@ -0,0 +1,56 @@
+
+plugins {
+    id 'java'
+    id 'application'
+    id "org.jetbrains.kotlin.jvm"
+}
+
+java {
+    toolchain {
+        languageVersion = JavaLanguageVersion.of(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"
+
+    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'
+
+}
+
+sourceSets {
+    main {
+        java {
+            srcDirs = ["${project.projectDir}/src"]
+        }
+        resources {
+            srcDirs = ["${project.projectDir}/res"]
+        }
+    }
+    test {
+        java {
+            srcDirs = ["${project.projectDir}/test"]
+        }
+    }
+}
+
+
+test {
+    // Enable JUnit 5 (Gradle 4.6+).
+    useJUnitPlatform()
+
+    // Always run tests, even when nothing changed.
+    dependsOn 'cleanTest'
+
+    // Show test results.
+    testLogging {
+        events "skipped", "failed"
+    }
+}

codeGeneration/codeGeneration.iml

@@ -0,0 +1,19 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<module type="JAVA_MODULE" version="4">
+  <component name="NewModuleRootManager" inherit-compiler-output="true">
+    <exclude-output />
+    <content url="file://$MODULE_DIR$">
+      <sourceFolder url="file://$MODULE_DIR$/src" isTestSource="false" />
+      <sourceFolder url="file://$MODULE_DIR$/test" isTestSource="true" />
+      <excludeFolder url="file://$MODULE_DIR$/build" />
+    </content>
+    <orderEntry type="jdk" jdkName="openjdk-11" jdkType="JavaSDK" />
+    <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" />
+    <orderEntry type="library" scope="TEST" name="hamcrest" level="project" />
+    <orderEntry type="library" name="junit.jupiter" level="project" />
+  </component>
+</module>

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

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

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

@@ -0,0 +1,35 @@
+package prog8.compiler.target
+
+import com.github.michaelbull.result.fold
+import prog8.ast.base.ByteDatatypes
+import prog8.ast.base.DataType
+import prog8.ast.base.PassByReferenceDatatypes
+import prog8.ast.base.WordDatatypes
+import prog8.compiler.target.c64.C64MachineDefinition
+import prog8.compiler.target.cbm.Petscii
+import prog8.compilerinterface.ICompilationTarget
+
+
+object C64Target: ICompilationTarget {
+    override val name = "c64"
+    override val machine = C64MachineDefinition
+    override fun encodeString(str: String, altEncoding: Boolean): List<Short> {
+        val coded = if (altEncoding) Petscii.encodeScreencode(str, true) else Petscii.encodePetscii(str, true)
+        return coded.fold(
+            failure = { throw it },
+            success = { it }
+        )
+    }
+    override fun decodeString(bytes: List<Short>, altEncoding: Boolean) =
+        if (altEncoding) Petscii.decodeScreencode(bytes, true) else Petscii.decodePetscii(bytes, true)
+
+    override fun memorySize(dt: DataType): Int {
+        return when(dt) {
+            in ByteDatatypes -> 1
+            in WordDatatypes -> 2
+            DataType.FLOAT -> machine.FLOAT_MEM_SIZE
+            in PassByReferenceDatatypes -> machine.POINTER_MEM_SIZE
+            else -> -9999999
+        }
+    }
+}

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

@@ -0,0 +1,36 @@
+package prog8.compiler.target
+
+import com.github.michaelbull.result.fold
+import prog8.ast.base.ByteDatatypes
+import prog8.ast.base.DataType
+import prog8.ast.base.PassByReferenceDatatypes
+import prog8.ast.base.WordDatatypes
+import prog8.compiler.target.cbm.Petscii
+import prog8.compiler.target.cx16.CX16MachineDefinition
+import prog8.compilerinterface.ICompilationTarget
+
+
+object Cx16Target: ICompilationTarget {
+    override val name = "cx16"
+    override val machine = CX16MachineDefinition
+    override fun encodeString(str: String, altEncoding: Boolean): List<Short> {
+        val coded= if (altEncoding) Petscii.encodeScreencode(str, true) else Petscii.encodePetscii(str, true)
+        return coded.fold(
+            failure = { throw it },
+            success = { it }
+        )
+    }
+    override fun decodeString(bytes: List<Short>, altEncoding: Boolean) =
+        if (altEncoding) Petscii.decodeScreencode(bytes, true) else Petscii.decodePetscii(bytes, true)
+
+    override fun memorySize(dt: DataType): Int {
+        return when(dt) {
+            in ByteDatatypes -> 1
+            in WordDatatypes -> 2
+            DataType.FLOAT -> machine.FLOAT_MEM_SIZE
+            in PassByReferenceDatatypes -> machine.POINTER_MEM_SIZE
+            else -> -9999999
+        }
+    }
+}
+

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

@@ -1,14 +1,13 @@
 package prog8.compiler.target.c64
 
-import prog8.compiler.*
-import prog8.compiler.target.CpuType
-import prog8.compiler.target.IMachineDefinition
-import prog8.compiler.target.IMachineFloat
+import prog8.compiler.target.cbm.viceMonListPostfix
+import prog8.compilerinterface.*
 import java.io.IOException
+import java.nio.file.Path
 import kotlin.math.absoluteValue
 import kotlin.math.pow
 
-internal object C64MachineDefinition: IMachineDefinition {
+object C64MachineDefinition: IMachineDefinition {
 
     override val cpu = CpuType.CPU6502
 
@@ -28,18 +27,23 @@ internal object C64MachineDefinition: IMachineDefinition {
 
     override fun getFloat(num: Number) = Mflpt5.fromNumber(num)
 
-    override fun importLibs(compilerOptions: CompilationOptions,compilationTargetName: String): List<String> {
+    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(programName: String) {
+    override fun launchEmulator(selectedEmulator: Int, programNameWithPath: Path) {
+        if(selectedEmulator!=1) {
+            System.err.println("The c64 target only supports the main emulator (Vice).")
+            return
+        }
+
         for(emulator in listOf("x64sc", "x64")) {
             println("\nStarting C-64 emulator $emulator...")
-            val cmdline = listOf(emulator, "-silent", "-moncommands", "$programName.vice-mon-list",
-                    "-autostartprgmode", "1", "-autostart-warp", "-autostart", "$programName.prg")
+            val cmdline = listOf(emulator, "-silent", "-moncommands", "${programNameWithPath}.$viceMonListPostfix",
+                    "-autostartprgmode", "1", "-autostart-warp", "-autostart", "${programNameWithPath}.prg")
             val processb = ProcessBuilder(cmdline).inheritIO()
             val process: Process
             try {
@@ -70,7 +74,7 @@ internal object C64MachineDefinition: IMachineDefinition {
             "sta", "stx", "sty", "tas", "tax", "tay", "tsx", "txa", "txs", "tya", "xaa")
 
 
-    internal class C64Zeropage(options: CompilationOptions) : Zeropage(options) {
+    class C64Zeropage(options: CompilationOptions) : Zeropage(options) {
 
         override val SCRATCH_B1 = 0x02      // temp storage for a single byte
         override val SCRATCH_REG = 0x03     // temp storage for a register, must be B1+1
@@ -79,13 +83,12 @@ internal object C64MachineDefinition: IMachineDefinition {
 
 
         init {
-            if (options.floats && options.zeropage !in setOf(ZeropageType.FLOATSAFE, ZeropageType.BASICSAFE, ZeropageType.DONTUSE ))
-                throw CompilerException("when floats are enabled, zero page type should be 'floatsafe' or 'basicsafe' or 'dontuse'")
+            if (options.floats && options.zeropage !in arrayOf(ZeropageType.FLOATSAFE, ZeropageType.BASICSAFE, ZeropageType.DONTUSE ))
+                throw InternalCompilerException("when floats are enabled, zero page type should be 'floatsafe' or 'basicsafe' or 'dontuse'")
 
             if (options.zeropage == ZeropageType.FULL) {
                 free.addAll(0x04..0xf9)
                 free.add(0xff)
-                free.removeAll(listOf(SCRATCH_B1, SCRATCH_REG, SCRATCH_W1, SCRATCH_W1 + 1, SCRATCH_W2, SCRATCH_W2 + 1))
                 free.removeAll(listOf(0xa0, 0xa1, 0xa2, 0x91, 0xc0, 0xc5, 0xcb, 0xf5, 0xf6))        // these are updated by IRQ
             } else {
                 if (options.zeropage == ZeropageType.KERNALSAFE || options.zeropage == ZeropageType.FLOATSAFE) {
@@ -107,7 +110,7 @@ internal object C64MachineDefinition: IMachineDefinition {
                 }
 
                 if (options.zeropage == ZeropageType.FLOATSAFE) {
-                    // remove the zero page locations used for floating point operations from the free list
+                    // 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,
@@ -118,7 +121,7 @@ internal object C64MachineDefinition: IMachineDefinition {
                     ))
                 }
 
-                if(options.zeropage!=ZeropageType.DONTUSE) {
+                if(options.zeropage!= ZeropageType.DONTUSE) {
                     // add the free Zp addresses
                     // these are valid for the C-64 but allow BASIC to keep running fully *as long as you don't use tape I/O*
                     free.addAll(listOf(0x04, 0x05, 0x06, 0x0a, 0x0e,
@@ -129,17 +132,13 @@ internal object C64MachineDefinition: IMachineDefinition {
                     free.clear()
                 }
             }
-            require(SCRATCH_B1 !in free)
-            require(SCRATCH_REG !in free)
-            require(SCRATCH_W1 !in free)
-            require(SCRATCH_W2 !in free)
 
-            for (reserved in options.zpReserved)
-                reserve(reserved)
+            removeReservedFromFreePool()
         }
     }
 
-    internal data class Mflpt5(val b0: Short, val b1: Short, val b2: Short, val b3: Short, val b4: Short): IMachineFloat {
+    data class Mflpt5(val b0: Short, val b1: Short, val b2: Short, val b3: Short, val b4: Short):
+        IMachineFloat {
 
         companion object {
             val zero = Mflpt5(0, 0, 0, 0, 0)
@@ -150,7 +149,7 @@ internal object C64MachineDefinition: IMachineDefinition {
 
                 val flt = num.toDouble()
                 if (flt < FLOAT_MAX_NEGATIVE || flt > FLOAT_MAX_POSITIVE)
-                    throw CompilerException("floating point number out of 5-byte mflpt range: $this")
+                    throw InternalCompilerException("floating point number out of 5-byte mflpt range: $this")
                 if (flt == 0.0)
                     return zero
 
@@ -171,7 +170,7 @@ internal object C64MachineDefinition: IMachineDefinition {
 
                 return when {
                     exponent < 0 -> zero  // underflow, use zero instead
-                    exponent > 255 -> throw CompilerException("floating point overflow: $this")
+                    exponent > 255 -> throw InternalCompilerException("floating point overflow: $this")
                     exponent == 0 -> zero
                     else -> {
                         val mantLong = mantissa.toLong()

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

@@ -1,24 +1,41 @@
 package prog8.compiler.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.compilerinterface.CompilationOptions
+import prog8.compilerinterface.IAssemblyProgram
+import prog8.compilerinterface.OutputType
+import prog8.compilerinterface.generatedLabelPrefix
+import prog8.parser.SourceCode
+import java.io.File
 import java.nio.file.Path
-import kotlin.system.exitProcess
+import kotlin.io.path.Path
+import kotlin.io.path.isRegularFile
+
+
+internal const val viceMonListPostfix = "vice-mon-list"
+
+class AssemblyProgram(
+        override val valid: Boolean,
+        override val name: String,
+        outputDir: Path,
+        private val compTarget: String) : IAssemblyProgram {
 
-class AssemblyProgram(override val name: String, outputDir: Path, private val compTarget: String) : IAssemblyProgram {
     private val assemblyFile = outputDir.resolve("$name.asm")
     private val prgFile = outputDir.resolve("$name.prg")
     private val binFile = outputDir.resolve("$name.bin")
-    private val viceMonListFile = outputDir.resolve("$name.vice-mon-list")
+    private val viceMonListFile = outputDir.resolve("$name.$viceMonListPostfix")
 
-    override fun assemble(options: CompilationOptions) {
+    override fun assemble(quiet: Boolean, options: CompilationOptions): Int {
         // add "-Wlong-branch"  to see warnings about conversion of branch instructions to jumps (default = do this silently)
         val command = mutableListOf("64tass", "--ascii", "--case-sensitive", "--long-branch",
                 "-Wall", "-Wno-strict-bool", "-Wno-shadow", // "-Werror",
                 "--dump-labels", "--vice-labels", "-l", viceMonListFile.toString(), "--no-monitor")
 
+        if(quiet)
+            command.add("--quiet")
+
         val outFile = when (options.output) {
             OutputType.PRG -> {
                 command.add("--cbm-prg")
@@ -35,13 +52,11 @@ class AssemblyProgram(override val name: String, outputDir: Path, private val co
 
         val proc = ProcessBuilder(command).inheritIO().start()
         val result = proc.waitFor()
-        if (result != 0) {
-            System.err.println("assembler failed with returncode $result")
-            exitProcess(result)
+        if (result == 0) {
+            removeGeneratedLabelsFromMonlist()
+            generateBreakpointList()
         }
-
-        removeGeneratedLabelsFromMonlist()
-        generateBreakpointList()
+        return result
     }
 
     private fun removeGeneratedLabelsFromMonlist() {
@@ -71,3 +86,18 @@ class AssemblyProgram(override val name: String, outputDir: Path, private val co
         viceMonListFile.toFile().appendText(breakpoints.joinToString("\n") + "\n")
     }
 }
+
+
+internal fun loadAsmIncludeFile(filename: String, source: SourceCode): Result<String, NoSuchFileException> {
+    return if (filename.startsWith(SourceCode.libraryFilePrefix)) {
+        return com.github.michaelbull.result.runCatching {
+            SourceCode.Resource("/prog8lib/${filename.substring(SourceCode.libraryFilePrefix.length)}").readText()
+        }.mapError { NoSuchFileException(File(filename)) }
+    } else {
+        val sib = Path(source.origin).resolveSibling(filename)
+        if (sib.isRegularFile())
+            Ok(SourceCode.File(sib).readText())
+        else
+            Ok(SourceCode.File(Path(filename)).readText())
+    }
+}

codeGeneration/src/prog8/compiler/target/cpu6502/codegen/AsmGen.kt

@@ -1,27 +1,32 @@
 package prog8.compiler.target.cpu6502.codegen
 
+import com.github.michaelbull.result.fold
 import prog8.ast.*
 import prog8.ast.antlr.escape
 import prog8.ast.base.*
 import prog8.ast.expressions.*
 import prog8.ast.statements.*
-import prog8.compiler.*
-import prog8.compiler.functions.BuiltinFunctions
-import prog8.compiler.functions.FSignature
-import prog8.compiler.target.*
+import prog8.compiler.target.AssemblyError
+import prog8.compiler.target.C64Target
+import prog8.compiler.target.Cx16Target
 import prog8.compiler.target.cbm.AssemblyProgram
+import prog8.compiler.target.cbm.loadAsmIncludeFile
+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.AssignmentAsmGen
-import prog8.optimizer.CallGraph
+import prog8.compiler.target.cpu6502.codegen.assignment.SourceStorageKind
+import prog8.compilerinterface.*
+import prog8.parser.SourceCode
 import java.nio.file.Path
-import java.nio.file.Paths
 import java.time.LocalDate
 import java.time.LocalDateTime
 import java.util.*
+import kotlin.io.path.Path
 import kotlin.math.absoluteValue
 
 
-internal class AsmGen(private val program: Program,
+class AsmGen(private val program: Program,
                       val errors: IErrorReporter,
                       val zeropage: Zeropage,
                       val options: CompilationOptions,
@@ -44,9 +49,9 @@ internal class AsmGen(private val program: Program,
     private val assignmentAsmGen = AssignmentAsmGen(program, this, expressionsAsmGen)
     private val builtinFunctionsAsmGen = BuiltinFunctionsAsmGen(program, this, assignmentAsmGen)
     internal val loopEndLabels = ArrayDeque<String>()
-    private val blockLevelVarInits = mutableMapOf<Block, MutableSet<VarDecl>>()
     internal val slabs = mutableMapOf<String, Int>()
-    internal val removals = mutableListOf<Pair<Statement, INameScope>>()
+    internal val removals = mutableListOf<Pair<Statement, IStatementContainer>>()
+    private val blockVariableInitializers = program.allBlocks.associateWith { it.statements.filterIsInstance<Assignment>() }
 
     override fun compileToAssembly(): IAssemblyProgram {
         assemblyLines.clear()
@@ -55,11 +60,14 @@ internal class AsmGen(private val program: Program,
         println("Generating assembly code... ")
 
         header()
-        val allBlocks = program.allBlocks()
+        val allBlocks = program.allBlocks
         if(allBlocks.first().name != "main")
             throw AssemblyError("first block should be 'main'")
-        for(b in program.allBlocks())
+
+        for(b in program.allBlocks) {
+            b.statements.removeAll(blockVariableInitializers.getValue(b))  // no longer output the initialization assignments as regular statements in the block!
             block2asm(b)
+        }
 
         for(removal in removals.toList()) {
             removal.second.remove(removal.first)
@@ -86,7 +94,11 @@ internal class AsmGen(private val program: Program,
             }
         }
 
-        return AssemblyProgram(program.name, outputDir, compTarget.name)
+        return if(errors.noErrors())
+            AssemblyProgram(true, program.name, outputDir, compTarget.name)
+        else {
+            AssemblyProgram(false, "<error>", outputDir, compTarget.name)
+        }
     }
 
     internal fun isTargetCpu(cpu: CpuType) = compTarget.machine.cpu == cpu
@@ -148,7 +160,7 @@ internal class AsmGen(private val program: Program,
             }
         }
 
-        if(options.zeropage !in setOf(ZeropageType.BASICSAFE, ZeropageType.DONTUSE)) {
+        if(options.zeropage !in arrayOf(ZeropageType.BASICSAFE, ZeropageType.DONTUSE)) {
             out("""
                 ; zeropage is clobbered so we need to reset the machine at exit
                 lda  #>sys.reset_system
@@ -212,26 +224,17 @@ internal class AsmGen(private val program: Program,
         stmts.forEach { translate(it) }
         subroutine.forEach { translateSubroutine(it as Subroutine) }
 
-        // if any global vars need to be initialized, generate a subroutine that does this
-        // it will be called from program init.
-        if(block in blockLevelVarInits) {
+        // generate subroutine to initialize block-level variables
+        val initializers = blockVariableInitializers.getValue(block)
+        if(initializers.isNotEmpty()) {
             out("prog8_init_vars\t.proc\n")
-            blockLevelVarInits.getValue(block).forEach { decl ->
-                val scopedFullName = decl.makeScopedName(decl.name).split('.')
-                require(scopedFullName.first()==block.name)
-                assignInitialValueToVar(decl, scopedFullName.drop(1))
-            }
+            initializers.forEach { assign -> translate(assign) }
             out("  rts\n  .pend")
         }
 
         out(if("force_output" in block.options()) "\n\t.bend\n" else "\n\t.pend\n")
     }
 
-    private fun assignInitialValueToVar(decl: VarDecl, variableName: List<String>) {
-        val asmName = asmVariableName(variableName)
-        assignmentAsmGen.assignExpressionToVariable(decl.value!!, asmName, decl.datatype, decl.definingSubroutine())
-    }
-
     private var generatedLabelSequenceNumber: Int = 0
 
     internal fun makeLabel(postfix: String): String {
@@ -268,7 +271,6 @@ internal class AsmGen(private val program: Program,
                         && variable.datatype != DataType.FLOAT
                         && options.zeropage != ZeropageType.DONTUSE) {
                     try {
-                        val errors = ErrorReporter()
                         val address = zeropage.allocate(fullName, variable.datatype, null, errors)
                         errors.report()
                         out("${variable.name} = $address\t; auto zp ${variable.datatype}")
@@ -493,7 +495,7 @@ internal class AsmGen(private val program: Program,
         return newName
     }
 
-    internal fun asmSymbolName(identifier: IdentifierReference): String {
+    fun asmSymbolName(identifier: IdentifierReference): String {
         if(identifier.nameInSource.size==2 && identifier.nameInSource[0]=="prog8_slabs")
             return identifier.nameInSource.joinToString(".")
 
@@ -502,17 +504,19 @@ internal class AsmGen(private val program: Program,
             return identifier.nameInSource.joinToString(".")
 
         val target = identifier.targetStatement(program)!!
-        val targetScope = target.definingSubroutine()
-        val identScope = identifier.definingSubroutine()
+        val targetScope = target.definingSubroutine
+        val identScope = identifier.definingSubroutine
         return if(targetScope !== identScope) {
             val scopedName = getScopedSymbolNameForTarget(identifier.nameInSource.last(), target)
             if(target is Label) {
+                // make labels locally scoped in the asm. Is slightly problematic, see github issue #62
                 val last = scopedName.removeLast()
                 scopedName.add("_$last")
             }
             fixNameSymbols(scopedName.joinToString("."))
         } else {
             if(target is Label) {
+                // make labels locally scoped in the asm. Is slightly problematic, see github issue #62
                 val scopedName = identifier.nameInSource.toMutableList()
                 val last = scopedName.removeLast()
                 scopedName.add("_$last")
@@ -522,7 +526,7 @@ internal class AsmGen(private val program: Program,
         }
     }
 
-    internal fun asmVariableName(identifier: IdentifierReference) =
+    fun asmVariableName(identifier: IdentifierReference) =
         fixNameSymbols(identifier.nameInSource.joinToString("."))
 
     private fun getScopedSymbolNameForTarget(actualName: String, target: Statement): MutableList<String> {
@@ -549,14 +553,14 @@ internal class AsmGen(private val program: Program,
     internal fun asmVariableName(name: Iterable<String>) = fixNameSymbols(name.joinToString("."))
 
 
-    internal fun loadByteFromPointerIntoA(pointervar: IdentifierReference): Pair<Boolean, String> {
-        // returns if the pointer is already on the ZP itself or not (in the latter case SCRATCH_W1 is used as intermediary)
-        val target = pointervar.targetStatement(program)
-        when (target) {
+    internal fun loadByteFromPointerIntoA(pointervar: IdentifierReference): String {
+        // returns the source name of the zero page pointervar if it's already in the ZP,
+        // otherwise returns "P8ZP_SCRATCH_W1" which is the intermediary
+        when (val target = pointervar.targetStatement(program)) {
             is Label -> {
                 val sourceName = asmSymbolName(pointervar)
                 out("  lda  $sourceName")
-                return Pair(true, sourceName)
+                return sourceName
             }
             is VarDecl -> {
                 val sourceName = asmVariableName(pointervar)
@@ -565,7 +569,7 @@ internal class AsmGen(private val program: Program,
                     return if (isZpVar(scopedName)) {
                         // pointervar is already in the zero page, no need to copy
                         out("  lda  ($sourceName)")
-                        Pair(true, sourceName)
+                        sourceName
                     } else {
                         out("""
                             lda  $sourceName
@@ -573,13 +577,13 @@ internal class AsmGen(private val program: Program,
                             sta  P8ZP_SCRATCH_W1
                             sty  P8ZP_SCRATCH_W1+1
                             lda  (P8ZP_SCRATCH_W1)""")
-                        Pair(false, sourceName)
+                        "P8ZP_SCRATCH_W1"
                     }
                 } else {
                     return if (isZpVar(scopedName)) {
                         // pointervar is already in the zero page, no need to copy
                         out("  ldy  #0 |  lda  ($sourceName),y")
-                        Pair(true, sourceName)
+                        sourceName
                     } else {
                         out("""
                             lda  $sourceName
@@ -588,7 +592,7 @@ internal class AsmGen(private val program: Program,
                             sty  P8ZP_SCRATCH_W1+1
                             ldy  #0
                             lda  (P8ZP_SCRATCH_W1),y""")
-                        Pair(false, sourceName)
+                        "P8ZP_SCRATCH_W1"
                     }
                 }
             }
@@ -828,12 +832,10 @@ internal class AsmGen(private val program: Program,
         }
     }
 
+    @Deprecated("avoid calling this as it generates slow evalstack based code")
     internal fun translateExpression(expression: Expression) =
             expressionsAsmGen.translateExpression(expression)
 
-    internal fun translateExpression(indexer: ArrayIndex) =
-            expressionsAsmGen.translateExpression(indexer)
-
     internal fun translateBuiltinFunctionCallExpression(functionCall: FunctionCall, signature: FSignature, resultToStack: Boolean, resultRegister: RegisterOrPair?) =
             builtinFunctionsAsmGen.translateFunctioncallExpression(functionCall, signature, resultToStack, resultRegister)
 
@@ -849,14 +851,53 @@ internal class AsmGen(private val program: Program,
     internal fun translateNormalAssignment(assign: AsmAssignment) =
             assignmentAsmGen.translateNormalAssignment(assign)
 
-    internal fun assignExpressionToRegister(expr: Expression, register: RegisterOrPair) =
-            assignmentAsmGen.assignExpressionToRegister(expr, register)
+    internal fun assignExpressionToRegister(expr: Expression, register: RegisterOrPair, signed: Boolean=false) =
+            assignmentAsmGen.assignExpressionToRegister(expr, register, signed)
 
     internal fun assignExpressionToVariable(expr: Expression, asmVarName: String, dt: DataType, scope: Subroutine?) =
             assignmentAsmGen.assignExpressionToVariable(expr, asmVarName, dt, scope)
 
-    internal fun assignVariableToRegister(asmVarName: String, register: RegisterOrPair) =
-            assignmentAsmGen.assignVariableToRegister(asmVarName, register)
+    internal fun assignVariableToRegister(asmVarName: String, register: RegisterOrPair, signed: Boolean=false) =
+            assignmentAsmGen.assignVariableToRegister(asmVarName, register, signed)
+
+    internal fun assignRegister(reg: RegisterOrPair, target: AsmAssignTarget) {
+        when(reg) {
+            RegisterOrPair.A,
+            RegisterOrPair.X,
+            RegisterOrPair.Y -> assignmentAsmGen.assignRegisterByte(target, reg.asCpuRegister())
+            RegisterOrPair.AX,
+            RegisterOrPair.AY,
+            RegisterOrPair.XY,
+            in Cx16VirtualRegisters -> assignmentAsmGen.assignRegisterpairWord(target, reg)
+            RegisterOrPair.FAC1 -> assignmentAsmGen.assignFAC1float(target)
+            RegisterOrPair.FAC2 -> TODO("no support yet to assign FAC2 directly to something")
+            else -> throw AssemblyError("invalid register")
+        }
+    }
+
+    internal fun assignExpressionTo(value: Expression, target: AsmAssignTarget) {
+        // don't use asmgen.translateExpression() to avoid evalstack
+        when (target.datatype) {
+            in ByteDatatypes -> {
+                assignExpressionToRegister(value, RegisterOrPair.A)
+                assignRegister(RegisterOrPair.A, target)
+            }
+            in WordDatatypes, in PassByReferenceDatatypes -> {
+                assignExpressionToRegister(value, RegisterOrPair.AY)
+                translateNormalAssignment(
+                    AsmAssignment(
+                        AsmAssignSource(SourceStorageKind.REGISTER, program, this, target.datatype, register=RegisterOrPair.AY),
+                        target, false, program.memsizer, value.position
+                    )
+                )
+            }
+            DataType.FLOAT -> {
+                assignExpressionToRegister(value, RegisterOrPair.FAC1)
+                assignRegister(RegisterOrPair.FAC1, target)
+            }
+            else -> throw AssemblyError("weird dt ${target.datatype}")
+        }
+    }
 
 
     private fun translateSubroutine(sub: Subroutine) {
@@ -864,7 +905,7 @@ internal class AsmGen(private val program: Program,
 
         if(sub.inline) {
             if(options.optimize) {
-                if(sub.isAsmSubroutine ||callGraph.unused(sub))
+                if(sub.isAsmSubroutine || callGraph.unused(sub))
                     return
 
                 // from an inlined subroutine only the local variables are generated,
@@ -873,7 +914,7 @@ internal class AsmGen(private val program: Program,
                 onlyVariables = true
             }
             else if(sub.amountOfRtsInAsm()==0) {
-                // make sure the NOT INLINED subroutine actually does an rts at the end
+                // make sure the NOT INLINED subroutine actually does a rts at the end
                 sub.statements.add(Return(null, Position.DUMMY))
             }
         }
@@ -897,12 +938,12 @@ internal class AsmGen(private val program: Program,
             memdefs2asm(sub.statements)
 
             // the main.start subroutine is the program's entrypoint and should perform some initialization logic
-            if(sub.name=="start" && sub.definingBlock().name=="main") {
+            if(sub.name=="start" && sub.definingBlock.name=="main") {
                 out("; program startup initialization")
                 out("  cld")
-                program.allBlocks().forEach {
-                    if(it.statements.filterIsInstance<VarDecl>().any { vd->vd.value!=null && vd.type==VarDeclType.VAR && vd.datatype in NumericDatatypes})
-                        out("  jsr  ${it.name}.prog8_init_vars")
+                blockVariableInitializers.forEach {
+                    if(it.value.isNotEmpty())
+                        out("  jsr  ${it.key.name}.prog8_init_vars")
                 }
                 out("""
                     tsx
@@ -975,15 +1016,14 @@ internal class AsmGen(private val program: Program,
             }
 
     private fun translate(stmt: IfStatement) {
-        checkBooleanExpression(stmt.condition)  // we require the condition to be of the form  'x <comparison> <value>'
+        requireComparisonExpression(stmt.condition)  // IfStatement: condition must be of form  'x <comparison> <value>'
         val booleanCondition = stmt.condition as BinaryExpression
 
         // DISABLED FOR NOW:
 //        if(!booleanCondition.left.isSimple || !booleanCondition.right.isSimple)
 //            throw AssemblyError("both operands for if comparison expression should have been simplified")
 
-        if (stmt.elsepart.containsNoCodeNorVars()) {
-            // empty else
+        if (stmt.elsepart.isEmpty()) {
             val endLabel = makeLabel("if_end")
             expressionsAsmGen.translateComparisonExpressionWithJumpIfFalse(booleanCondition, endLabel)
             translate(stmt.truepart)
@@ -1002,9 +1042,9 @@ internal class AsmGen(private val program: Program,
         }
     }
 
-    private fun checkBooleanExpression(condition: Expression) {
+    private fun requireComparisonExpression(condition: Expression) {
         if(condition !is BinaryExpression || condition.operator !in comparisonOperators)
-            throw AssemblyError("expected boolean expression $condition")
+            throw AssemblyError("expected boolean comparison expression $condition")
     }
 
     private fun translate(stmt: RepeatLoop) {
@@ -1055,7 +1095,7 @@ internal class AsmGen(private val program: Program,
                 val dt = stmt.iterations!!.inferType(program)
                 if(!dt.isKnown)
                     throw AssemblyError("unknown dt")
-                when (dt.typeOrElse(DataType.UNDEFINED)) {
+                when (dt.getOr(DataType.UNDEFINED)) {
                     in ByteDatatypes -> {
                         assignExpressionToRegister(stmt.iterations!!, RegisterOrPair.A)
                         repeatByteCountInA(null, repeatLabel, endLabel, stmt)
@@ -1076,7 +1116,7 @@ internal class AsmGen(private val program: Program,
         // note: A/Y must have been loaded with the number of iterations!
         if(constIterations==0)
             return
-        // no need to explicitly test for 0 iterations as this is done in the count down logic below
+        // no need to explicitly test for 0 iterations as this is done in the countdown logic below
 
         val counterVar: String = createRepeatCounterVar(DataType.UWORD, constIterations, stmt)
         out("""
@@ -1097,7 +1137,7 @@ $repeatLabel    lda  $counterVar
     }
 
     private fun repeatByteCountInA(constIterations: Int?, repeatLabel: String, endLabel: String, stmt: RepeatLoop) {
-        // note: A must have been loaded with the number of iterations!
+        // note: A must be loaded with the number of iterations!
         if(constIterations==0)
             return
 
@@ -1113,7 +1153,7 @@ $repeatLabel    lda  $counterVar
     }
 
     private fun createRepeatCounterVar(dt: DataType, constIterations: Int?, stmt: RepeatLoop): String {
-        val asmInfo = stmt.definingSubroutine()!!.asmGenInfo
+        val asmInfo = stmt.definingSubroutine!!.asmGenInfo
         var parent = stmt.parent
         while(parent !is ParentSentinel) {
             if(parent is RepeatLoop)
@@ -1155,7 +1195,7 @@ $repeatLabel    lda  $counterVar
     }
 
     private fun translate(stmt: WhileLoop) {
-        checkBooleanExpression(stmt.condition)  // we require the condition to be of the form  'x <comparison> <value>'
+        requireComparisonExpression(stmt.condition)  // WhileLoop: condition must be of form  'x <comparison> <value>'
         val booleanCondition = stmt.condition as BinaryExpression
         val whileLabel = makeLabel("while")
         val endLabel = makeLabel("whileend")
@@ -1169,7 +1209,7 @@ $repeatLabel    lda  $counterVar
     }
 
     private fun translate(stmt: UntilLoop) {
-        checkBooleanExpression(stmt.condition)  // we require the condition to be of the form  'x <comparison> <value>'
+        requireComparisonExpression(stmt.condition)  // UntilLoop: condition must be of form  'x <comparison> <value>'
         val booleanCondition = stmt.condition as BinaryExpression
         val repeatLabel = makeLabel("repeat")
         val endLabel = makeLabel("repeatend")
@@ -1187,7 +1227,7 @@ $repeatLabel    lda  $counterVar
         val conditionDt = stmt.condition.inferType(program)
         if(!conditionDt.isKnown)
             throw AssemblyError("unknown condition dt")
-        if(conditionDt.typeOrElse(DataType.BYTE) in ByteDatatypes)
+        if(conditionDt.getOr(DataType.BYTE) in ByteDatatypes)
             assignExpressionToRegister(stmt.condition, RegisterOrPair.A)
         else
             assignExpressionToRegister(stmt.condition, RegisterOrPair.AY)
@@ -1202,7 +1242,7 @@ $repeatLabel    lda  $counterVar
                 choiceBlocks.add(choiceLabel to choice.statements)
                 for (cv in choice.values!!) {
                     val value = (cv as NumericLiteralValue).number.toInt()
-                    if(conditionDt.typeOrElse(DataType.BYTE) in ByteDatatypes) {
+                    if(conditionDt.getOr(DataType.BYTE) in ByteDatatypes) {
                         out("  cmp  #${value.toHex()} |  beq  $choiceLabel")
                     } else {
                         out("""
@@ -1226,7 +1266,8 @@ $repeatLabel    lda  $counterVar
     }
 
     private fun translate(stmt: Label) {
-        out("_${stmt.name}")        // underscore prefix to make sure it's a local label
+        // underscore prefix to make sure it's a local label. Is slightly problematic, see github issue #62
+        out("_${stmt.name}")
     }
 
     private fun translate(scope: AnonymousScope) {
@@ -1235,7 +1276,7 @@ $repeatLabel    lda  $counterVar
     }
 
     private fun translate(stmt: BranchStatement) {
-        if(stmt.truepart.containsNoCodeNorVars() && stmt.elsepart.containsCodeOrVars())
+        if(stmt.truepart.isEmpty() && stmt.elsepart.isNotEmpty())
             throw AssemblyError("only else part contains code, shoud have been switched already")
 
         val jump = stmt.truepart.statements.first() as? Jump
@@ -1247,7 +1288,7 @@ $repeatLabel    lda  $counterVar
         } else {
             val truePartIsJustBreak = stmt.truepart.statements.firstOrNull() is Break
             val elsePartIsJustBreak = stmt.elsepart.statements.firstOrNull() is Break
-            if(stmt.elsepart.containsNoCodeNorVars()) {
+            if(stmt.elsepart.isEmpty()) {
                 if(truePartIsJustBreak) {
                     // branch with just a break (jump out of loop)
                     val instruction = branchInstruction(stmt.condition, false)
@@ -1287,39 +1328,37 @@ $repeatLabel    lda  $counterVar
         }
     }
 
-    private fun translate(stmt: VarDecl) {
-        if(stmt.value!=null && stmt.type==VarDeclType.VAR && stmt.datatype in NumericDatatypes) {
-            // generate an assignment statement to (re)initialize the variable's value.
-            // if the vardecl is not in a subroutine however, we have to initialize it globally.
-            if(stmt.definingSubroutine()==null) {
-                val block = stmt.definingBlock()
-                var inits = blockLevelVarInits[block]
-                if(inits==null) {
-                    inits = mutableSetOf()
-                    blockLevelVarInits[block] = inits
-                }
-                inits.add(stmt)
-            } else {
-                val next = (stmt.parent as INameScope).nextSibling(stmt)
-                if (next !is ForLoop || next.loopVar.nameInSource.single() != stmt.name) {
-                    assignInitialValueToVar(stmt, listOf(stmt.name))
-                }
-            }
-        }
+    private fun translate(decl: VarDecl) {
+        if(decl.type==VarDeclType.VAR && decl.value != null && decl.datatype in NumericDatatypes)
+            throw AssemblyError("vardecls for variables, with initial numerical value, should have been rewritten as plain vardecl + assignment $decl")
+        // at this time, nothing has to be done here anymore code-wise
     }
 
     private fun translate(stmt: Directive) {
         when(stmt.directive) {
             "%asminclude" -> {
-                val sourcecode = loadAsmIncludeFile(stmt.args[0].str!!, stmt.definingModule().source)
-                assemblyLines.add(sourcecode.trimEnd().trimStart('\n'))
+                val includedName = stmt.args[0].str!!
+                if(stmt.definingModule.source is SourceCode.Generated)
+                    TODO("%asminclude inside non-library, non-filesystem module")
+                loadAsmIncludeFile(includedName, stmt.definingModule.source).fold(
+                    success = { assemblyLines.add(it.trimEnd().trimStart('\n')) },
+                    failure = { errors.err(it.toString(), stmt.position) }
+                )
             }
             "%asmbinary" -> {
+                val includedName = stmt.args[0].str!!
                 val offset = if(stmt.args.size>1) ", ${stmt.args[1].int}" else ""
                 val length = if(stmt.args.size>2) ", ${stmt.args[2].int}" else ""
-                val includedSourcePath = stmt.definingModule().source.resolveSibling(stmt.args[0].str)
-                val relPath = Paths.get("").relativize(includedSourcePath)
-                out("  .binary \"$relPath\" $offset $length")
+                if(stmt.definingModule.source is SourceCode.Generated)
+                    TODO("%asmbinary inside non-library, non-filesystem module")
+                val sourcePath = Path(stmt.definingModule.source.origin)
+                val includedPath = sourcePath.resolveSibling(includedName)
+                val pathForAssembler = outputDir // #54: 64tass needs the path *relative to the .asm file*
+                    .toAbsolutePath()
+                    .relativize(includedPath.toAbsolutePath())
+                    .normalize() // avoid assembler warnings (-Wportable; only some, not all)
+                    .toString().replace('\\', '/')
+                out("  .binary \"$pathForAssembler\" $offset $length")
             }
             "%breakpoint" -> {
                 val label = "_prog8_breakpoint_${breakpointLabels.size+1}"
@@ -1347,7 +1386,7 @@ $label              nop""")
 
     internal fun translate(ret: Return, withRts: Boolean=true) {
         ret.value?.let { returnvalue ->
-            val sub = ret.definingSubroutine()!!
+            val sub = ret.definingSubroutine!!
             val returnType = sub.returntypes.single()
             val returnReg = sub.asmReturnvaluesRegisters.single()
             if(returnReg.registerOrPair==null)
@@ -1360,7 +1399,7 @@ $label              nop""")
                 else -> {
                     // all else take its address and assign that also to AY register pair
                     val addrofValue = AddressOf(returnvalue as IdentifierReference, returnvalue.position)
-                    assignmentAsmGen.assignExpressionToRegister(addrofValue, returnReg.registerOrPair!!)
+                    assignmentAsmGen.assignExpressionToRegister(addrofValue, returnReg.registerOrPair!!, false)
                 }
             }
         }
@@ -1436,22 +1475,22 @@ $label              nop""")
         if(pointerOffsetExpr is BinaryExpression && pointerOffsetExpr.operator=="+") {
             val leftDt = pointerOffsetExpr.left.inferType(program)
             val rightDt = pointerOffsetExpr.left.inferType(program)
-            if(leftDt.istype(DataType.UWORD) && rightDt.istype(DataType.UBYTE))
+            if(leftDt istype DataType.UWORD && rightDt istype DataType.UBYTE)
                 return Pair(pointerOffsetExpr.left, pointerOffsetExpr.right)
-            if(leftDt.istype(DataType.UBYTE) && rightDt.istype(DataType.UWORD))
+            if(leftDt istype DataType.UBYTE && rightDt istype DataType.UWORD)
                 return Pair(pointerOffsetExpr.right, pointerOffsetExpr.left)
-            if(leftDt.istype(DataType.UWORD) && rightDt.istype(DataType.UWORD)) {
+            if(leftDt istype DataType.UWORD && rightDt istype DataType.UWORD) {
                 // could be that the index was a constant numeric byte but converted to word, check that
                 val constIdx = pointerOffsetExpr.right.constValue(program)
                 if(constIdx!=null && constIdx.number.toInt()>=0 && constIdx.number.toInt()<=255) {
                     return Pair(pointerOffsetExpr.left, NumericLiteralValue(DataType.UBYTE, constIdx.number, constIdx.position))
                 }
-                // could be that the index was type casted into uword, check that
+                // could be that the index was typecasted into uword, check that
                 val rightTc = pointerOffsetExpr.right as? TypecastExpression
-                if(rightTc!=null && rightTc.expression.inferType(program).istype(DataType.UBYTE))
+                if(rightTc!=null && rightTc.expression.inferType(program) istype DataType.UBYTE)
                     return Pair(pointerOffsetExpr.left, rightTc.expression)
                 val leftTc = pointerOffsetExpr.left as? TypecastExpression
-                if(leftTc!=null && leftTc.expression.inferType(program).istype(DataType.UBYTE))
+                if(leftTc!=null && leftTc.expression.inferType(program) istype DataType.UBYTE)
                     return Pair(pointerOffsetExpr.right, leftTc.expression)
             }
 
@@ -1464,7 +1503,7 @@ $label              nop""")
 
         fun evalBytevalueWillClobberA(expr: Expression): Boolean {
             val dt = expr.inferType(program)
-            if(!dt.istype(DataType.UBYTE) && !dt.istype(DataType.BYTE))
+            if(dt isnot DataType.UBYTE && dt isnot DataType.BYTE)
                 return true
             return when(expr) {
                 is IdentifierReference -> false
@@ -1480,8 +1519,7 @@ $label              nop""")
             val ptrAndIndex = pointerViaIndexRegisterPossible(expr)
             if(ptrAndIndex!=null) {
                 val pointervar = ptrAndIndex.first as? IdentifierReference
-                val target = pointervar?.targetStatement(program)
-                when(target) {
+                when(pointervar?.targetStatement(program)) {
                     is Label -> {
                         assignExpressionToRegister(ptrAndIndex.second, RegisterOrPair.Y)
                         out("  lda  ${asmSymbolName(pointervar)},y")

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

@@ -74,7 +74,7 @@ private fun getLinesBy(lines: MutableList<String>, windowSize: Int) =
         lines.withIndex().filter { it.value.isNotBlank() && !it.value.trimStart().startsWith(';') }.windowed(windowSize, partialWindows = false)
 
 private fun optimizeCmpSequence(linesByFour: List<List<IndexedValue<String>>>): List<Modification> {
-    // the when statement (on bytes) generates a sequence of:
+    // when statement (on bytes) generates a sequence of:
     //	 lda  $ce01,x
     //	 cmp  #$20
     //	 beq  check_prog8_s72choice_32
@@ -180,7 +180,7 @@ private fun optimizeSameAssignments(linesByFourteen: List<List<IndexedValue<Stri
 
 private fun optimizeStoreLoadSame(linesByFour: List<List<IndexedValue<String>>>): List<Modification> {
     // sta X + lda X,  sty X + ldy X,   stx X + ldx X  -> the second instruction can OFTEN be eliminated
-    // TODO this is not true if X is not a regular RAM memory address (but instead mapped I/O or ROM)
+    // TODO this is not true if X is not a regular RAM memory address (but instead mapped I/O or ROM) but how does this code know?
     val mods = mutableListOf<Modification>()
     for (pair in linesByFour) {
         val first = pair[0].value.trimStart()

codeGeneration/src/prog8/compiler/target/cpu6502/codegen/BuiltinFunctionsAsmGen.kt

@@ -10,12 +10,12 @@ 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.AssemblyError
 import prog8.compiler.target.Cx16Target
 import prog8.compiler.target.cpu6502.codegen.assignment.*
-import prog8.compiler.target.subroutineFloatEvalResultVar2
+import prog8.compilerinterface.CpuType
+import prog8.compilerinterface.FSignature
+import prog8.compilerinterface.subroutineFloatEvalResultVar2
 
 internal class BuiltinFunctionsAsmGen(private val program: Program, private val asmgen: AsmGen, private val assignAsmGen: AssignmentAsmGen) {
 
@@ -34,7 +34,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
         if(discardResult && resultToStack)
             throw AssemblyError("cannot both discard the result AND put it onto stack")
 
-        val sscope = (fcall as Node).definingSubroutine()
+        val sscope = (fcall as Node).definingSubroutine
 
         when (func.name) {
             "msb" -> funcMsb(fcall, resultToStack, resultRegister)
@@ -177,8 +177,8 @@ 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).typeOrElse(DataType.UNDEFINED)
-        val dt2 = arg2.inferType(program).typeOrElse(DataType.UNDEFINED)
+        val dt1 = arg1.inferType(program).getOr(DataType.UNDEFINED)
+        val dt2 = arg2.inferType(program).getOr(DataType.UNDEFINED)
         if(dt1 in ByteDatatypes) {
             if(dt2 in ByteDatatypes) {
                 when (arg2) {
@@ -195,13 +195,13 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                             asmgen.assignExpressionToRegister(arg1, RegisterOrPair.A)
                             asmgen.out("  cmp  ${arg2.addressExpression.constValue(program)!!.number.toHex()}")
                         } else {
-                            asmgen.assignExpressionToVariable(arg2, "P8ZP_SCRATCH_B1", DataType.UBYTE, (fcall as Node).definingSubroutine())
+                            asmgen.assignExpressionToVariable(arg2, "P8ZP_SCRATCH_B1", DataType.UBYTE, (fcall as Node).definingSubroutine)
                             asmgen.assignExpressionToRegister(arg1, RegisterOrPair.A)
                             asmgen.out("  cmp  P8ZP_SCRATCH_B1")
                         }
                     }
                     else -> {
-                        asmgen.assignExpressionToVariable(arg2, "P8ZP_SCRATCH_B1", DataType.UBYTE, (fcall as Node).definingSubroutine())
+                        asmgen.assignExpressionToVariable(arg2, "P8ZP_SCRATCH_B1", DataType.UBYTE, (fcall as Node).definingSubroutine)
                         asmgen.assignExpressionToRegister(arg1, RegisterOrPair.A)
                         asmgen.out("  cmp  P8ZP_SCRATCH_B1")
                     }
@@ -229,7 +229,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
 +""")
                     }
                     else -> {
-                        asmgen.assignExpressionToVariable(arg2, "P8ZP_SCRATCH_W1", DataType.UWORD, (fcall as Node).definingSubroutine())
+                        asmgen.assignExpressionToVariable(arg2, "P8ZP_SCRATCH_W1", DataType.UWORD, (fcall as Node).definingSubroutine)
                         asmgen.assignExpressionToRegister(arg1, RegisterOrPair.AY)
                         asmgen.out("""
                             cpy  P8ZP_SCRATCH_W1+1
@@ -261,7 +261,7 @@ 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 +273,7 @@ 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)
         }
     }
 
@@ -285,11 +285,11 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
             when(func.name) {
                 "sin8", "sin8u", "cos8", "cos8u" -> {
                     asmgen.out("  jsr  prog8_lib.func_${func.name}_into_A")
-                    assignAsmGen.assignRegisterByte(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.A, scope, program, asmgen), CpuRegister.A)
+                    assignAsmGen.assignRegisterByte(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.A, false, scope, program, asmgen), CpuRegister.A)
                 }
                 "sin16", "sin16u", "cos16", "cos16u" -> {
                     asmgen.out("  jsr  prog8_lib.func_${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)
                 }
             }
     }
@@ -368,7 +368,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
     private fun funcRor2(fcall: IFunctionCall) {
         val what = fcall.args.single()
         val dt = what.inferType(program)
-        when (dt.typeOrElse(DataType.UNDEFINED)) {
+        when (dt.getOr(DataType.UNDEFINED)) {
             DataType.UBYTE -> {
                 when (what) {
                     is ArrayIndexedExpression -> {
@@ -411,7 +411,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
     private fun funcRor(fcall: IFunctionCall) {
         val what = fcall.args.single()
         val dt = what.inferType(program)
-        when (dt.typeOrElse(DataType.UNDEFINED)) {
+        when (dt.getOr(DataType.UNDEFINED)) {
             DataType.UBYTE -> {
                 when (what) {
                     is ArrayIndexedExpression -> {
@@ -426,7 +426,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                             val ptrAndIndex = asmgen.pointerViaIndexRegisterPossible(what.addressExpression)
                             if(ptrAndIndex!=null) {
                                 asmgen.assignExpressionToRegister(ptrAndIndex.second, RegisterOrPair.X)
-                                asmgen.saveRegisterLocal(CpuRegister.X, (fcall as FunctionCallStatement).definingSubroutine()!!)
+                                asmgen.saveRegisterLocal(CpuRegister.X, (fcall as FunctionCallStatement).definingSubroutine!!)
                                 asmgen.assignExpressionToRegister(ptrAndIndex.first, RegisterOrPair.AY)
                                 asmgen.restoreRegisterLocal(CpuRegister.X)
                                 asmgen.out("""
@@ -469,7 +469,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
     private fun funcRol2(fcall: IFunctionCall) {
         val what = fcall.args.single()
         val dt = what.inferType(program)
-        when (dt.typeOrElse(DataType.UNDEFINED)) {
+        when (dt.getOr(DataType.UNDEFINED)) {
             DataType.UBYTE -> {
                 when (what) {
                     is ArrayIndexedExpression -> {
@@ -512,7 +512,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
     private fun funcRol(fcall: IFunctionCall) {
         val what = fcall.args.single()
         val dt = what.inferType(program)
-        when (dt.typeOrElse(DataType.UNDEFINED)) {
+        when (dt.getOr(DataType.UNDEFINED)) {
             DataType.UBYTE -> {
                 when (what) {
                     is ArrayIndexedExpression -> {
@@ -527,7 +527,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                             val ptrAndIndex = asmgen.pointerViaIndexRegisterPossible(what.addressExpression)
                             if(ptrAndIndex!=null) {
                                 asmgen.assignExpressionToRegister(ptrAndIndex.second, RegisterOrPair.X)
-                                asmgen.saveRegisterLocal(CpuRegister.X, (fcall as FunctionCallStatement).definingSubroutine()!!)
+                                asmgen.saveRegisterLocal(CpuRegister.X, (fcall as FunctionCallStatement).definingSubroutine!!)
                                 asmgen.assignExpressionToRegister(ptrAndIndex.first, RegisterOrPair.AY)
                                 asmgen.restoreRegisterLocal(CpuRegister.X)
                                 asmgen.out("""
@@ -578,7 +578,7 @@ 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))
         }
     }
 
@@ -586,7 +586,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
         translateArguments(fcall.args, func, scope)
         val dt = fcall.args.single().inferType(program)
         if(resultToStack) {
-            when (dt.typeOrElse(DataType.UNDEFINED)) {
+            when (dt.getOr(DataType.UNDEFINED)) {
                 DataType.UBYTE -> asmgen.out("  jsr  prog8_lib.func_sign_ub_stack")
                 DataType.BYTE -> asmgen.out("  jsr  prog8_lib.func_sign_b_stack")
                 DataType.UWORD -> asmgen.out("  jsr  prog8_lib.func_sign_uw_stack")
@@ -595,7 +595,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                 else -> throw AssemblyError("weird type $dt")
             }
         } else {
-            when (dt.typeOrElse(DataType.UNDEFINED)) {
+            when (dt.getOr(DataType.UNDEFINED)) {
                 DataType.UBYTE -> asmgen.out("  jsr  prog8_lib.func_sign_ub_into_A")
                 DataType.BYTE -> asmgen.out("  jsr  prog8_lib.func_sign_b_into_A")
                 DataType.UWORD -> asmgen.out("  jsr  prog8_lib.func_sign_uw_into_A")
@@ -603,7 +603,7 @@ 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)
         }
     }
 
@@ -611,20 +611,20 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
         outputAddressAndLenghtOfArray(fcall.args[0])
         val dt = fcall.args.single().inferType(program)
         if(resultToStack) {
-            when (dt.typeOrElse(DataType.UNDEFINED)) {
+            when (dt.getOr(DataType.UNDEFINED)) {
                 DataType.ARRAY_B, DataType.ARRAY_UB, DataType.STR -> asmgen.out("  jsr  prog8_lib.func_${function.name}_b_stack")
                 DataType.ARRAY_UW, DataType.ARRAY_W -> asmgen.out("  jsr  prog8_lib.func_${function.name}_w_stack")
                 DataType.ARRAY_F -> asmgen.out("  jsr  floats.func_${function.name}_f_stack")
                 else -> throw AssemblyError("weird type $dt")
             }
         } else {
-            when (dt.typeOrElse(DataType.UNDEFINED)) {
+            when (dt.getOr(DataType.UNDEFINED)) {
                 DataType.ARRAY_B, DataType.ARRAY_UB, DataType.STR -> asmgen.out("  jsr  prog8_lib.func_${function.name}_b_into_A")
                 DataType.ARRAY_UW, DataType.ARRAY_W -> asmgen.out("  jsr  prog8_lib.func_${function.name}_w_into_A")
                 DataType.ARRAY_F -> asmgen.out("  jsr  floats.func_${function.name}_f_into_A")
                 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)
         }
     }
 
@@ -632,7 +632,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
         outputAddressAndLenghtOfArray(fcall.args[0])
         val dt = fcall.args.single().inferType(program)
         if(resultToStack) {
-            when (dt.typeOrElse(DataType.UNDEFINED)) {
+            when (dt.getOr(DataType.UNDEFINED)) {
                 DataType.ARRAY_UB, DataType.STR -> asmgen.out("  jsr  prog8_lib.func_${function.name}_ub_stack")
                 DataType.ARRAY_B -> asmgen.out("  jsr  prog8_lib.func_${function.name}_b_stack")
                 DataType.ARRAY_UW -> asmgen.out("  jsr  prog8_lib.func_${function.name}_uw_stack")
@@ -641,26 +641,26 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                 else -> throw AssemblyError("weird type $dt")
             }
         } else {
-            when (dt.typeOrElse(DataType.UNDEFINED)) {
+            when (dt.getOr(DataType.UNDEFINED)) {
                 DataType.ARRAY_UB, DataType.STR -> {
                     asmgen.out("  jsr  prog8_lib.func_${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")
             }
@@ -671,7 +671,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
         outputAddressAndLenghtOfArray(fcall.args[0])
         val dt = fcall.args.single().inferType(program)
         if(resultToStack) {
-            when (dt.typeOrElse(DataType.UNDEFINED)) {
+            when (dt.getOr(DataType.UNDEFINED)) {
                 DataType.ARRAY_UB, DataType.STR -> asmgen.out("  jsr  prog8_lib.func_sum_ub_stack")
                 DataType.ARRAY_B -> asmgen.out("  jsr  prog8_lib.func_sum_b_stack")
                 DataType.ARRAY_UW -> asmgen.out("  jsr  prog8_lib.func_sum_uw_stack")
@@ -680,26 +680,26 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                 else -> throw AssemblyError("weird type $dt")
             }
         } else {
-            when (dt.typeOrElse(DataType.UNDEFINED)) {
+            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")
             }
@@ -715,11 +715,11 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
             val firstName = asmgen.asmVariableName(first)
             val secondName = asmgen.asmVariableName(second)
             val dt = first.inferType(program)
-            if(dt.istype(DataType.BYTE) || dt.istype(DataType.UBYTE)) {
+            if(dt istype DataType.BYTE || dt istype DataType.UBYTE) {
                 asmgen.out(" ldy  $firstName |  lda  $secondName |  sta  $firstName |  sty  $secondName")
                 return
             }
-            if(dt.istype(DataType.WORD) || dt.istype(DataType.UWORD)) {
+            if(dt istype DataType.WORD || dt istype DataType.UWORD) {
                 asmgen.out("""
                     ldy  $firstName
                     lda  $secondName
@@ -732,7 +732,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                 """)
                 return
             }
-            if(dt.istype(DataType.FLOAT)) {
+            if(dt istype DataType.FLOAT) {
                 asmgen.out("""
                     lda  #<$firstName
                     sta  P8ZP_SCRATCH_W1
@@ -750,7 +750,6 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
 
         // optimized simple case: swap two memory locations
         if(first is DirectMemoryRead && second is DirectMemoryRead) {
-            // TODO optimize swap of two memread values with index, using the same pointer expression/variable, like swap(@(ptr+i1), @(ptr+i2))
             val addr1 = (first.addressExpression as? NumericLiteralValue)?.number?.toHex()
             val addr2 = (second.addressExpression as? NumericLiteralValue)?.number?.toHex()
             val name1 = if(first.addressExpression is IdentifierReference) asmgen.asmVariableName(first.addressExpression as IdentifierReference) else null
@@ -773,6 +772,49 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                     asmgen.out("  ldy  $name1 |  lda  $name2 |  sta  $name1 |  sty  $name2")
                     return
                 }
+                addr1==null && addr2==null && name1==null && name2==null -> {
+                    val firstExpr = first.addressExpression as? BinaryExpression
+                    val secondExpr = second.addressExpression as? BinaryExpression
+                    if(firstExpr!=null && secondExpr!=null) {
+                        val pointerVariable = firstExpr.left as? IdentifierReference
+                        val firstOffset = firstExpr.right
+                        val secondOffset = secondExpr.right
+                        if(pointerVariable != null
+                            && pointerVariable isSameAs secondExpr.left
+                            && firstExpr.operator == "+" && secondExpr.operator == "+"
+                            && (firstOffset is NumericLiteralValue || firstOffset is IdentifierReference || firstOffset is TypecastExpression)
+                            && (secondOffset is NumericLiteralValue || secondOffset is IdentifierReference || secondOffset is TypecastExpression)
+                        ) {
+                            if(firstOffset is NumericLiteralValue && secondOffset is NumericLiteralValue) {
+                                if(firstOffset!=secondOffset) {
+                                    swapArrayValues(
+                                        DataType.UBYTE,
+                                        asmgen.asmVariableName(pointerVariable), firstOffset,
+                                        asmgen.asmVariableName(pointerVariable), secondOffset
+                                    )
+                                    return
+                                }
+                            } else if(firstOffset is TypecastExpression && secondOffset is TypecastExpression) {
+                                if(firstOffset.type in WordDatatypes && secondOffset.type in WordDatatypes) {
+                                    val firstOffsetVar = firstOffset.expression as? IdentifierReference
+                                    val secondOffsetVar = secondOffset.expression as? IdentifierReference
+                                    if(firstOffsetVar!=null && secondOffsetVar!=null) {
+                                        if(firstOffsetVar!=secondOffsetVar) {
+                                            swapArrayValues(
+                                                DataType.UBYTE,
+                                                asmgen.asmVariableName(pointerVariable), firstOffsetVar,
+                                                asmgen.asmVariableName(pointerVariable), secondOffsetVar
+                                            )
+                                            return
+                                        }
+                                    }
+                                }
+                            } else if(firstOffset is IdentifierReference || secondOffset is IdentifierReference) {
+                                throw AssemblyError("expected a typecast-to-word for index variable at ${firstOffset.position} and/or ${secondOffset.position}")
+                            }
+                        }
+                    }
+                }
             }
         }
 
@@ -782,7 +824,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
             val elementIDt = first.inferType(program)
             if(!elementIDt.isKnown)
                 throw AssemblyError("unknown dt")
-            val elementDt = elementIDt.typeOrElse(DataType.UNDEFINED)
+            val elementDt = elementIDt.getOr(DataType.UNDEFINED)
 
             val firstNum = first.indexer.indexExpr as? NumericLiteralValue
             val firstVar = first.indexer.indexExpr as? IdentifierReference
@@ -808,15 +850,14 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
 
         fun targetFromExpr(expr: Expression, datatype: DataType): AsmAssignTarget {
             return when (expr) {
-                is IdentifierReference -> AsmAssignTarget(TargetStorageKind.VARIABLE, program, asmgen, datatype, expr.definingSubroutine(), variableAsmName = asmgen.asmVariableName(expr))
-                is ArrayIndexedExpression -> AsmAssignTarget(TargetStorageKind.ARRAY, program, asmgen, datatype, expr.definingSubroutine(), array = expr)
-                is DirectMemoryRead -> AsmAssignTarget(TargetStorageKind.MEMORY, program, asmgen, datatype, expr.definingSubroutine(), memory = DirectMemoryWrite(expr.addressExpression, expr.position))
+                is IdentifierReference -> AsmAssignTarget(TargetStorageKind.VARIABLE, program, asmgen, datatype, expr.definingSubroutine, variableAsmName = asmgen.asmVariableName(expr))
+                is ArrayIndexedExpression -> AsmAssignTarget(TargetStorageKind.ARRAY, program, asmgen, datatype, expr.definingSubroutine, array = expr)
+                is DirectMemoryRead -> AsmAssignTarget(TargetStorageKind.MEMORY, program, asmgen, datatype, expr.definingSubroutine, memory = DirectMemoryWrite(expr.addressExpression, expr.position))
                 else -> throw AssemblyError("invalid expression object $expr")
             }
         }
 
-        val datatype = first.inferType(program).typeOrElse(DataType.UNDEFINED)
-        when(datatype) {
+        when(val datatype: DataType = first.inferType(program).getOr(DataType.UNDEFINED)) {
             in ByteDatatypes, in WordDatatypes -> {
                 asmgen.assignExpressionToVariable(first, "P8ZP_SCRATCH_W1", datatype, null)
                 asmgen.assignExpressionToVariable(second, "P8ZP_SCRATCH_W2", datatype, null)
@@ -834,21 +875,23 @@ 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")
         }
@@ -888,7 +931,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                     sta  P8ZP_SCRATCH_W2
                     lda  #>(${arrayVarName2}+$index2)
                     sta  P8ZP_SCRATCH_W2+1
-                    jsr  floats.swap_floats
+                    jsr  floats.func_swap_f
                 """)
             }
             else -> throw AssemblyError("invalid aray elt type")
@@ -961,7 +1004,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                     sta  P8ZP_SCRATCH_W2
                     bcc  +
                     inc  P8ZP_SCRATCH_W2+1
-+                   jsr  floats.swap_floats                                   
++                   jsr  floats.func_swap_f                                   
                 """)
             }
             else -> throw AssemblyError("invalid aray elt type")
@@ -1019,7 +1062,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                     sta  P8ZP_SCRATCH_W1
                     bcc  +
                     inc  P8ZP_SCRATCH_W1+1
-+                   jsr  floats.swap_floats
++                   jsr  floats.func_swap_f
                 """)
             }
             else -> throw AssemblyError("invalid aray elt type")
@@ -1077,7 +1120,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                     sta  P8ZP_SCRATCH_W2
                     lda  #>(${arrayVarName2}+$index2)
                     sta  P8ZP_SCRATCH_W2+1
-                    jsr  floats.swap_floats
+                    jsr  floats.func_swap_f
                 """)
             }
             else -> throw AssemblyError("invalid aray elt type")
@@ -1086,7 +1129,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
 
     private fun funcAbs(fcall: IFunctionCall, func: FSignature, resultToStack: Boolean, resultRegister: RegisterOrPair?, scope: Subroutine?) {
         translateArguments(fcall.args, func, scope)
-        val dt = fcall.args.single().inferType(program).typeOrElse(DataType.UNDEFINED)
+        val dt = fcall.args.single().inferType(program).getOr(DataType.UNDEFINED)
         if(resultToStack) {
             when (dt) {
                 in ByteDatatypes -> asmgen.out("  jsr  prog8_lib.abs_b_stack")
@@ -1098,15 +1141,15 @@ 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")
             }
@@ -1120,7 +1163,7 @@ 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" -> {
@@ -1128,7 +1171,7 @@ 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")
@@ -1147,7 +1190,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                 val varname = asmgen.asmVariableName(addrExpr)
                 if(asmgen.isZpVar(addrExpr)) {
                     // pointervar is already in the zero page, no need to copy
-                    asmgen.saveRegisterLocal(CpuRegister.X, (fcall as Node).definingSubroutine()!!)
+                    asmgen.saveRegisterLocal(CpuRegister.X, (fcall as Node).definingSubroutine!!)
                     asmgen.assignExpressionToRegister(fcall.args[1], RegisterOrPair.AX)
                     if (asmgen.isTargetCpu(CpuType.CPU65c02)) {
                         asmgen.out("""
@@ -1172,7 +1215,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                     val varname = asmgen.asmVariableName(addrExpr.left as IdentifierReference)
                     if(asmgen.isZpVar(addrExpr.left as IdentifierReference)) {
                         // pointervar is already in the zero page, no need to copy
-                        asmgen.saveRegisterLocal(CpuRegister.X, (fcall as Node).definingSubroutine()!!)
+                        asmgen.saveRegisterLocal(CpuRegister.X, (fcall as Node).definingSubroutine!!)
                         asmgen.assignExpressionToRegister(fcall.args[1], RegisterOrPair.AX)
                         val index = (addrExpr.right as NumericLiteralValue).number.toHex()
                         asmgen.out("""
@@ -1324,7 +1367,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
 
     private fun funcMsb(fcall: IFunctionCall, resultToStack: Boolean, resultRegister: RegisterOrPair?) {
         val arg = fcall.args.single()
-        if (!arg.inferType(program).isWords())
+        if (!arg.inferType(program).isWords)
             throw AssemblyError("msb required word argument")
         if (arg is NumericLiteralValue)
             throw AssemblyError("msb(const) should have been const-folded away")
@@ -1368,7 +1411,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
 
     private fun funcLsb(fcall: IFunctionCall, resultToStack: Boolean, resultRegister: RegisterOrPair?) {
         val arg = fcall.args.single()
-        if (!arg.inferType(program).isWords())
+        if (!arg.inferType(program).isWords)
             throw AssemblyError("lsb required word argument")
         if (arg is NumericLiteralValue)
             throw AssemblyError("lsb(const) should have been const-folded away")
@@ -1432,7 +1475,7 @@ 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).typeOrElse(DataType.UNDEFINED) })
+        val callConv = signature.callConvention(args.map { it.inferType(program).getOr(DataType.UNDEFINED) })
 
         fun getSourceForFloat(value: Expression): AsmAssignSource {
             return when (value) {
@@ -1491,7 +1534,7 @@ 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/compiler/target/cpu6502/codegen/ExpressionsAsmGen.kt

@@ -3,19 +3,27 @@ package prog8.compiler.target.cpu6502.codegen
 import prog8.ast.Program
 import prog8.ast.base.*
 import prog8.ast.expressions.*
-import prog8.ast.statements.ArrayIndex
 import prog8.ast.statements.BuiltinFunctionStatementPlaceholder
 import prog8.ast.statements.Subroutine
 import prog8.ast.toHex
-import prog8.compiler.AssemblyError
-import prog8.compiler.functions.BuiltinFunctions
-import prog8.compiler.target.CpuType
-import prog8.compiler.target.subroutineFloatEvalResultVar1
+import prog8.compiler.target.AssemblyError
+import prog8.compilerinterface.BuiltinFunctions
+import prog8.compilerinterface.CpuType
+import prog8.compilerinterface.subroutineFloatEvalResultVar1
 import kotlin.math.absoluteValue
 
 internal class ExpressionsAsmGen(private val program: Program, private val asmgen: AsmGen) {
 
-    internal fun translateExpression(expression: Expression) {
+    @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)
+    }
+
+    private fun translateExpressionInternal(expression: Expression) {
+
         when(expression) {
             is PrefixExpression -> translateExpression(expression)
             is BinaryExpression -> translateExpression(expression)
@@ -28,17 +36,21 @@ internal class ExpressionsAsmGen(private val program: Program, private val asmge
             is FunctionCall -> translateFunctionCallResultOntoStack(expression)
             is ArrayLiteralValue, is StringLiteralValue -> throw AssemblyError("no asm gen for string/array literal value assignment - should have been replaced by a variable")
             is RangeExpr -> throw AssemblyError("range expression should have been changed into array values")
+            is CharLiteral -> throw AssemblyError("charliteral should have been replaced by ubyte using certain encoding")
         }
     }
 
     internal fun translateComparisonExpressionWithJumpIfFalse(expr: BinaryExpression, jumpIfFalseLabel: String) {
-         // This is a helper routine called from while, do-util, and if expressions to generate optimized conditional branching code.
+        // This is a helper routine called from while, do-util, and if expressions to generate optimized conditional branching code.
         // First, if it is of the form:   <constvalue> <comparison> X  ,  then flip the expression so the constant is always the right operand.
+
         var left = expr.left
         var right = expr.right
         var operator = expr.operator
         var leftConstVal = left.constValue(program)
         var rightConstVal = right.constValue(program)
+
+        // make sure the constant value is on the right of the comparison expression
         if(leftConstVal!=null) {
             val tmp = left
             left = right
@@ -54,32 +66,113 @@ internal class ExpressionsAsmGen(private val program: Program, private val asmge
             }
         }
 
-        val idt = left.inferType(program)
-        if(!idt.isKnown)
-            throw AssemblyError("unknown dt")
-        val dt = idt.typeOrElse(DataType.UNDEFINED)
+        if (rightConstVal!=null && rightConstVal.number.toDouble() == 0.0)
+            jumpIfZeroOrNot(left, operator, jumpIfFalseLabel)
+        else
+            jumpIfComparison(left, operator, right, jumpIfFalseLabel, leftConstVal, rightConstVal)
+    }
+
+    private fun jumpIfZeroOrNot(
+        left: Expression,
+        operator: String,
+        jumpIfFalseLabel: String
+    ) {
+        when(val dt = left.inferType(program).getOr(DataType.UNDEFINED)) {
+            DataType.UBYTE, DataType.UWORD -> {
+                if(operator=="<") {
+                    asmgen.out("  jmp  $jumpIfFalseLabel")
+                    return
+                } else if(operator==">=") {
+                    return
+                }
+                if(dt==DataType.UBYTE) {
+                    asmgen.assignExpressionToRegister(left, RegisterOrPair.A, false)
+                    if (left is FunctionCall && !left.isSimple)
+                        asmgen.out("  cmp  #0")
+                } else {
+                    asmgen.assignExpressionToRegister(left, RegisterOrPair.AY, false)
+                    asmgen.out("  sty  P8ZP_SCRATCH_B1 |  ora  P8ZP_SCRATCH_B1")
+                }
+                when (operator) {
+                    "==" -> asmgen.out("  bne  $jumpIfFalseLabel")
+                    "!=" -> asmgen.out("  beq  $jumpIfFalseLabel")
+                    ">" -> asmgen.out("  beq  $jumpIfFalseLabel")
+                    "<=" -> asmgen.out("  bne  $jumpIfFalseLabel")
+                    else -> throw AssemblyError("invalid comparison operator $operator")
+                }
+            }
+            DataType.BYTE -> {
+                asmgen.assignExpressionToRegister(left, RegisterOrPair.A, true)
+                if (left is FunctionCall && !left.isSimple)
+                    asmgen.out("  cmp  #0")
+                when (operator) {
+                    "==" -> asmgen.out("  bne  $jumpIfFalseLabel")
+                    "!=" -> asmgen.out("  beq  $jumpIfFalseLabel")
+                    ">" -> asmgen.out("  beq  $jumpIfFalseLabel |  bmi  $jumpIfFalseLabel")
+                    "<" -> asmgen.out("  bpl  $jumpIfFalseLabel")
+                    ">=" -> asmgen.out("  bmi  $jumpIfFalseLabel")
+                    "<=" -> asmgen.out("""
+                          beq  +
+                          bpl  $jumpIfFalseLabel
+                      +   """)
+                    else -> throw AssemblyError("invalid comparison operator $operator")
+                }
+            }
+            DataType.WORD -> {
+                asmgen.assignExpressionToRegister(left, RegisterOrPair.AY, true)
+                when (operator) {
+                    "==" -> asmgen.out("  bne  $jumpIfFalseLabel |  cpy  #0 |  bne  $jumpIfFalseLabel")
+                    "!=" -> asmgen.out("  sty  P8ZP_SCRATCH_B1 |  ora  P8ZP_SCRATCH_B1 |  beq  $jumpIfFalseLabel")
+                    ">" -> asmgen.out("""
+                            cpy  #0
+                            bmi  $jumpIfFalseLabel
+                            bne  +
+                            cmp  #0
+                            beq  $jumpIfFalseLabel
+                        +   """)
+                    "<" -> asmgen.out("  cpy  #0 |  bpl  $jumpIfFalseLabel")
+                    ">=" -> asmgen.out("  cpy  #0 |  bmi  $jumpIfFalseLabel")
+                    "<=" -> asmgen.out("""
+                            cpy  #0
+                            bmi  +
+                            bne  $jumpIfFalseLabel
+                            cmp  #0
+                            bne  $jumpIfFalseLabel
+                        +   """)
+                    else -> throw AssemblyError("invalid comparison operator $operator")
+                }
+            }
+            DataType.FLOAT -> {
+                asmgen.assignExpressionToRegister(left, RegisterOrPair.FAC1)
+                asmgen.out("  jsr  floats.SIGN")   // SIGN(fac1) to A, $ff, $0, $1 for negative, zero, positive
+                when (operator) {
+                    "==" -> asmgen.out("  bne  $jumpIfFalseLabel")
+                    "!=" -> asmgen.out("  beq  $jumpIfFalseLabel")
+                    ">" -> asmgen.out("  bmi  $jumpIfFalseLabel |  beq  $jumpIfFalseLabel")
+                    "<" -> asmgen.out("  bpl  $jumpIfFalseLabel")
+                    ">=" -> asmgen.out("  bmi  $jumpIfFalseLabel")
+                    "<=" -> asmgen.out("  cmp  #1 |  beq  $jumpIfFalseLabel")
+                    else -> throw AssemblyError("invalid comparison operator $operator")
+                }
+            }
+            else -> {
+                throw AssemblyError("invalid dt")
+            }
+        }
+    }
+
+    private fun jumpIfComparison(
+        left: Expression,
+        operator: String,
+        right: Expression,
+        jumpIfFalseLabel: String,
+        leftConstVal: NumericLiteralValue?,
+        rightConstVal: NumericLiteralValue?
+    ) {
+        val dt = left.inferType(program).getOrElse { throw AssemblyError("unknown dt") }
+
         when (operator) {
             "==" -> {
-                // if the left operand is an expression, and the right is 0, we can just evaluate that expression,
-                // and use the result value directly to determine the boolean result. Shortcut only for integers.
-                if(rightConstVal?.number?.toDouble() == 0.0) {
-                    if(dt in ByteDatatypes) {
-                        asmgen.assignExpressionToRegister(left, RegisterOrPair.A)
-                        if(left is FunctionCall && !left.isSimple)
-                            asmgen.out("  cmp  #0")
-                        asmgen.out("  bne  $jumpIfFalseLabel")
-                        return
-                    }
-                    else if(dt in WordDatatypes) {
-                        asmgen.assignExpressionToRegister(left, RegisterOrPair.AY)
-                        asmgen.out("""
-                            sty  P8ZP_SCRATCH_B1
-                            ora  P8ZP_SCRATCH_B1
-                            bne  $jumpIfFalseLabel""")
-                        return
-                    }
-                }
-
                 when (dt) {
                     in ByteDatatypes -> translateByteEqualsJump(left, right, leftConstVal, rightConstVal, jumpIfFalseLabel)
                     in WordDatatypes -> translateWordEqualsJump(left, right, leftConstVal, rightConstVal, jumpIfFalseLabel)
@@ -89,26 +182,6 @@ internal class ExpressionsAsmGen(private val program: Program, private val asmge
                 }
             }
             "!=" -> {
-                // if the left operand is an expression, and the right is 0, we can just evaluate that expression,
-                // and use the result value directly to determine the boolean result. Shortcut only for integers.
-                if(rightConstVal?.number?.toDouble() == 0.0) {
-                    if(dt in ByteDatatypes) {
-                        asmgen.assignExpressionToRegister(left, RegisterOrPair.A)
-                        if(left is FunctionCall && !left.isSimple)
-                            asmgen.out("  cmp  #0")
-                        asmgen.out("  beq  $jumpIfFalseLabel")
-                        return
-                    }
-                    else if(dt in WordDatatypes) {
-                        asmgen.assignExpressionToRegister(left, RegisterOrPair.AY)
-                        asmgen.out("""
-                            sty  P8ZP_SCRATCH_B1
-                            ora  P8ZP_SCRATCH_B1
-                            beq  $jumpIfFalseLabel""")
-                        return
-                    }
-                }
-
                 when (dt) {
                     in ByteDatatypes -> translateByteNotEqualsJump(left, right, leftConstVal, rightConstVal, jumpIfFalseLabel)
                     in WordDatatypes -> translateWordNotEqualsJump(left, right, leftConstVal, rightConstVal, jumpIfFalseLabel)
@@ -197,7 +270,7 @@ internal class ExpressionsAsmGen(private val program: Program, private val asmge
                 jsr  floats.vars_less_f
                 beq  $jumpIfFalseLabel""")
         } else {
-            val subroutine = left.definingSubroutine()!!
+            val subroutine = left.definingSubroutine!!
             subroutine.asmGenInfo.usedFloatEvalResultVar1 = true
             asmgen.assignExpressionToVariable(right, subroutineFloatEvalResultVar1, DataType.FLOAT, subroutine)
             asmgen.assignExpressionToRegister(left, RegisterOrPair.FAC1)
@@ -242,7 +315,7 @@ internal class ExpressionsAsmGen(private val program: Program, private val asmge
                 jsr  floats.vars_lesseq_f
                 beq  $jumpIfFalseLabel""")
         } else {
-            val subroutine = left.definingSubroutine()!!
+            val subroutine = left.definingSubroutine!!
             subroutine.asmGenInfo.usedFloatEvalResultVar1 = true
             asmgen.assignExpressionToVariable(right, subroutineFloatEvalResultVar1, DataType.FLOAT, subroutine)
             asmgen.assignExpressionToRegister(left, RegisterOrPair.FAC1)
@@ -287,7 +360,7 @@ internal class ExpressionsAsmGen(private val program: Program, private val asmge
                 jsr  floats.vars_less_f
                 beq  $jumpIfFalseLabel""")
         } else {
-            val subroutine = left.definingSubroutine()!!
+            val subroutine = left.definingSubroutine!!
             subroutine.asmGenInfo.usedFloatEvalResultVar1 = true
             asmgen.assignExpressionToVariable(right, subroutineFloatEvalResultVar1, DataType.FLOAT, subroutine)
             asmgen.assignExpressionToRegister(left, RegisterOrPair.FAC1)
@@ -332,7 +405,7 @@ internal class ExpressionsAsmGen(private val program: Program, private val asmge
                 jsr  floats.vars_lesseq_f
                 beq  $jumpIfFalseLabel""")
         } else {
-            val subroutine = left.definingSubroutine()!!
+            val subroutine = left.definingSubroutine!!
             subroutine.asmGenInfo.usedFloatEvalResultVar1 = true
             asmgen.assignExpressionToVariable(right, subroutineFloatEvalResultVar1, DataType.FLOAT, subroutine)
             asmgen.assignExpressionToRegister(left, RegisterOrPair.FAC1)
@@ -1339,7 +1412,7 @@ internal class ExpressionsAsmGen(private val program: Program, private val asmge
                 jsr  floats.vars_equal_f
                 beq  $jumpIfFalseLabel""")
         } else {
-            val subroutine = left.definingSubroutine()!!
+            val subroutine = left.definingSubroutine!!
             subroutine.asmGenInfo.usedFloatEvalResultVar1 = true
             asmgen.assignExpressionToVariable(right, subroutineFloatEvalResultVar1, DataType.FLOAT, subroutine)
             asmgen.assignExpressionToRegister(left, RegisterOrPair.FAC1)
@@ -1424,7 +1497,7 @@ internal class ExpressionsAsmGen(private val program: Program, private val asmge
                 jsr  floats.vars_equal_f
                 bne  $jumpIfFalseLabel""")
         } else {
-            val subroutine = left.definingSubroutine()!!
+            val subroutine = left.definingSubroutine!!
             subroutine.asmGenInfo.usedFloatEvalResultVar1 = true
             asmgen.assignExpressionToVariable(right, subroutineFloatEvalResultVar1, DataType.FLOAT, subroutine)
             asmgen.assignExpressionToRegister(left, RegisterOrPair.FAC1)
@@ -1625,8 +1698,8 @@ internal class ExpressionsAsmGen(private val program: Program, private val asmge
     }
 
     private fun translateExpression(typecast: TypecastExpression) {
-        translateExpression(typecast.expression)
-        when(typecast.expression.inferType(program).typeOrElse(DataType.UNDEFINED)) {
+        translateExpressionInternal(typecast.expression)
+        when(typecast.expression.inferType(program).getOr(DataType.UNDEFINED)) {
             DataType.UBYTE -> {
                 when(typecast.type) {
                     DataType.UBYTE, DataType.BYTE -> {}
@@ -1757,7 +1830,7 @@ internal class ExpressionsAsmGen(private val program: Program, private val asmge
 
     private fun translateExpression(expr: IdentifierReference) {
         val varname = asmgen.asmVariableName(expr)
-        when(expr.inferType(program).typeOrElse(DataType.UNDEFINED)) {
+        when(expr.inferType(program).getOr(DataType.UNDEFINED)) {
             DataType.UBYTE, DataType.BYTE -> {
                 asmgen.out("  lda  $varname  |  sta  P8ESTACK_LO,x  |  dex")
             }
@@ -1775,23 +1848,23 @@ internal class ExpressionsAsmGen(private val program: Program, private val asmge
     }
 
     private fun translateExpression(expr: BinaryExpression) {
-        // TODO needs to use optimized assembly generation like the assignment instructions. But avoid code duplication.... rewrite all expressions into assignment form?
+        // 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.typeOrElse(DataType.UNDEFINED)
-        val rightDt = rightIDt.typeOrElse(DataType.UNDEFINED)
+        val leftDt = leftIDt.getOr(DataType.UNDEFINED)
+        val rightDt = rightIDt.getOr(DataType.UNDEFINED)
         // see if we can apply some optimized routines
-        // TODO avoid using evaluation on stack everywhere
         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) {
-                        translateExpression(expr.right)
+                        translateExpressionInternal(expr.right)
                         if(rightDt in ByteDatatypes) {
                             val incdec = if(leftVal<0) "dec" else "inc"
                             repeat(leftVal.absoluteValue) {
@@ -1821,7 +1894,7 @@ internal class ExpressionsAsmGen(private val program: Program, private val asmge
                     }
                     else if (rightVal!=null && rightVal in -4..4)
                     {
-                        translateExpression(expr.left)
+                        translateExpressionInternal(expr.left)
                         if(leftDt in ByteDatatypes) {
                             val incdec = if(rightVal<0) "dec" else "inc"
                             repeat(rightVal.absoluteValue) {
@@ -1856,7 +1929,7 @@ internal class ExpressionsAsmGen(private val program: Program, private val asmge
                     val rightVal = expr.right.constValue(program)?.number?.toInt()
                     if (rightVal!=null && rightVal in -4..4)
                     {
-                        translateExpression(expr.left)
+                        translateExpressionInternal(expr.left)
                         if(leftDt in ByteDatatypes) {
                             val incdec = if(rightVal<0) "inc" else "dec"
                             repeat(rightVal.absoluteValue) {
@@ -1889,7 +1962,7 @@ internal class ExpressionsAsmGen(private val program: Program, private val asmge
             ">>" -> {
                 val amount = expr.right.constValue(program)?.number?.toInt()
                 if(amount!=null) {
-                    translateExpression(expr.left)
+                    translateExpressionInternal(expr.left)
                     when (leftDt) {
                         DataType.UBYTE -> {
                             if (amount <= 2)
@@ -1960,7 +2033,7 @@ internal class ExpressionsAsmGen(private val program: Program, private val asmge
             "<<" -> {
                 val amount = expr.right.constValue(program)?.number?.toInt()
                 if(amount!=null) {
-                    translateExpression(expr.left)
+                    translateExpressionInternal(expr.left)
                     if (leftDt in ByteDatatypes) {
                         if (amount <= 2)
                             repeat(amount) { asmgen.out("  asl  P8ESTACK_LO+1,x") }
@@ -1997,7 +2070,7 @@ internal class ExpressionsAsmGen(private val program: Program, private val asmge
                         val amount = value.number.toInt()
                         if(amount==2) {
                             // optimize x*2 common case
-                            translateExpression(expr.left)
+                            translateExpressionInternal(expr.left)
                             if(leftDt in ByteDatatypes) {
                                 asmgen.out("  asl  P8ESTACK_LO+1,x")
                             } else {
@@ -2008,38 +2081,38 @@ internal class ExpressionsAsmGen(private val program: Program, private val asmge
                         when(rightDt) {
                             DataType.UBYTE -> {
                                 if(amount in asmgen.optimizedByteMultiplications) {
-                                    translateExpression(expr.left)
+                                    translateExpressionInternal(expr.left)
                                     asmgen.out(" jsr  math.stack_mul_byte_$amount")
                                     return
                                 }
                             }
                             DataType.BYTE -> {
                                 if(amount in asmgen.optimizedByteMultiplications) {
-                                    translateExpression(expr.left)
+                                    translateExpressionInternal(expr.left)
                                     asmgen.out(" jsr  math.stack_mul_byte_$amount")
                                     return
                                 }
                                 if(amount.absoluteValue in asmgen.optimizedByteMultiplications) {
-                                    translateExpression(expr.left)
+                                    translateExpressionInternal(expr.left)
                                     asmgen.out(" jsr  prog8_lib.neg_b |  jsr  math.stack_mul_byte_${amount.absoluteValue}")
                                     return
                                 }
                             }
                             DataType.UWORD -> {
                                 if(amount in asmgen.optimizedWordMultiplications) {
-                                    translateExpression(expr.left)
+                                    translateExpressionInternal(expr.left)
                                     asmgen.out(" jsr  math.stack_mul_word_$amount")
                                     return
                                 }
                             }
                             DataType.WORD -> {
                                 if(amount in asmgen.optimizedWordMultiplications) {
-                                    translateExpression(expr.left)
+                                    translateExpressionInternal(expr.left)
                                     asmgen.out(" jsr  math.stack_mul_word_$amount")
                                     return
                                 }
                                 if(amount.absoluteValue in asmgen.optimizedWordMultiplications) {
-                                    translateExpression(expr.left)
+                                    translateExpressionInternal(expr.left)
                                     asmgen.out(" jsr  prog8_lib.neg_w |  jsr  math.stack_mul_word_${amount.absoluteValue}")
                                     return
                                 }
@@ -2053,7 +2126,7 @@ internal class ExpressionsAsmGen(private val program: Program, private val asmge
                 if(leftDt in IntegerDatatypes && rightDt in IntegerDatatypes) {
                     val rightVal = expr.right.constValue(program)?.number?.toInt()
                     if(rightVal!=null && rightVal==2) {
-                        translateExpression(expr.left)
+                        translateExpressionInternal(expr.left)
                         when(leftDt) {
                             DataType.UBYTE -> asmgen.out("  lsr  P8ESTACK_LO+1,x")
                             DataType.BYTE -> asmgen.out("  asl  P8ESTACK_LO+1,x |  ror  P8ESTACK_LO+1,x")
@@ -2075,9 +2148,9 @@ internal class ExpressionsAsmGen(private val program: Program, private val asmge
             translateCompareStrings(expr.left, expr.operator, expr.right)
         }
         else {
-            // the general, non-optimized cases  TODO optimize more cases....
-            translateExpression(expr.left)
-            translateExpression(expr.right)
+            // 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)
@@ -2104,11 +2177,11 @@ internal class ExpressionsAsmGen(private val program: Program, private val asmge
     }
 
     private fun translateExpression(expr: PrefixExpression) {
-        translateExpression(expr.expression)
+        translateExpressionInternal(expr.expression)
         val itype = expr.inferType(program)
         if(!itype.isKnown)
             throw AssemblyError("unknown dt")
-        val type = itype.typeOrElse(DataType.UNDEFINED)
+        val type = itype.getOr(DataType.UNDEFINED)
         when(expr.operator) {
             "+" -> {}
             "-" -> {
@@ -2146,7 +2219,7 @@ internal class ExpressionsAsmGen(private val program: Program, private val asmge
         val elementIDt = arrayExpr.inferType(program)
         if(!elementIDt.isKnown)
             throw AssemblyError("unknown dt")
-        val elementDt = elementIDt.typeOrElse(DataType.UNDEFINED)
+        val elementDt = elementIDt.getOr(DataType.UNDEFINED)
         val arrayVarName = asmgen.asmVariableName(arrayExpr.arrayvar)
         val constIndexNum = arrayExpr.indexer.constIndex()
         if(constIndexNum!=null) {
@@ -2189,8 +2262,6 @@ internal class ExpressionsAsmGen(private val program: Program, private val asmge
         }
     }
 
-    fun translateExpression(indexer: ArrayIndex) = asmgen.translateExpression(indexer.indexExpr)
-
     private fun translateBinaryOperatorBytes(operator: String, types: DataType) {
         when(operator) {
             "**" -> throw AssemblyError("** operator requires floats")

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

@@ -8,7 +8,8 @@ import prog8.ast.expressions.IdentifierReference
 import prog8.ast.expressions.RangeExpr
 import prog8.ast.statements.ForLoop
 import prog8.ast.toHex
-import prog8.compiler.AssemblyError
+import prog8.compiler.target.AssemblyError
+import prog8.compilerinterface.toConstantIntegerRange
 import kotlin.math.absoluteValue
 
 internal class ForLoopsAsmGen(private val program: Program, private val asmgen: AsmGen) {
@@ -21,13 +22,13 @@ internal class ForLoopsAsmGen(private val program: Program, private val asmgen:
             is RangeExpr -> {
                 val range = (stmt.iterable as RangeExpr).toConstantIntegerRange()
                 if(range==null) {
-                    translateForOverNonconstRange(stmt, iterableDt.typeOrElse(DataType.UNDEFINED), stmt.iterable as RangeExpr)
+                    translateForOverNonconstRange(stmt, iterableDt.getOr(DataType.UNDEFINED), stmt.iterable as RangeExpr)
                 } else {
-                    translateForOverConstRange(stmt, iterableDt.typeOrElse(DataType.UNDEFINED), range)
+                    translateForOverConstRange(stmt, iterableDt.getOr(DataType.UNDEFINED), range)
                 }
             }
             is IdentifierReference -> {
-                translateForOverIterableVar(stmt, iterableDt.typeOrElse(DataType.UNDEFINED), stmt.iterable as IdentifierReference)
+                translateForOverIterableVar(stmt, iterableDt.getOr(DataType.UNDEFINED), stmt.iterable as IdentifierReference)
             }
             else -> throw AssemblyError("can't iterate over ${stmt.iterable.javaClass} - should have been replaced by a variable")
         }
@@ -588,5 +589,5 @@ $loopLabel""")
     }
 
     private fun assignLoopvar(stmt: ForLoop, range: RangeExpr) =
-        asmgen.assignExpressionToVariable(range.from, asmgen.asmVariableName(stmt.loopVar), stmt.loopVarDt(program).typeOrElse(DataType.UNDEFINED), stmt.definingSubroutine())
+        asmgen.assignExpressionToVariable(range.from, asmgen.asmVariableName(stmt.loopVar), stmt.loopVarDt(program).getOr(DataType.UNDEFINED), stmt.definingSubroutine)
 }

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

@@ -5,13 +5,16 @@ import prog8.ast.Node
 import prog8.ast.Program
 import prog8.ast.base.*
 import prog8.ast.expressions.*
-import prog8.ast.statements.*
-import prog8.compiler.AssemblyError
-import prog8.compiler.target.CpuType
+import prog8.ast.statements.InlineAssembly
+import prog8.ast.statements.RegisterOrStatusflag
+import prog8.ast.statements.Subroutine
+import prog8.ast.statements.SubroutineParameter
+import prog8.compiler.target.AssemblyError
 import prog8.compiler.target.cpu6502.codegen.assignment.AsmAssignSource
 import prog8.compiler.target.cpu6502.codegen.assignment.AsmAssignTarget
 import prog8.compiler.target.cpu6502.codegen.assignment.AsmAssignment
 import prog8.compiler.target.cpu6502.codegen.assignment.TargetStorageKind
+import prog8.compilerinterface.CpuType
 
 
 internal class FunctionCallAsmGen(private val program: Program, private val asmgen: AsmGen) {
@@ -27,11 +30,10 @@ internal class FunctionCallAsmGen(private val program: Program, private val asmg
         val sub = stmt.target.targetSubroutine(program) ?: throw AssemblyError("undefined subroutine ${stmt.target}")
         if(sub.shouldSaveX()) {
             val regSaveOnStack = sub.asmAddress==null       // rom-routines don't require registers to be saved on stack, normal subroutines do because they can contain nested calls
-            val (keepAonEntry: Boolean, keepAonReturn: Boolean) = sub.shouldKeepA()
             if(regSaveOnStack)
-                asmgen.saveRegisterStack(CpuRegister.X, keepAonEntry)
+                asmgen.saveRegisterStack(CpuRegister.X, sub.shouldKeepA().saveOnEntry)
             else
-                asmgen.saveRegisterLocal(CpuRegister.X, (stmt as Node).definingSubroutine()!!)
+                asmgen.saveRegisterLocal(CpuRegister.X, (stmt as Node).definingSubroutine!!)
         }
     }
 
@@ -39,17 +41,15 @@ internal class FunctionCallAsmGen(private val program: Program, private val asmg
         val sub = stmt.target.targetSubroutine(program) ?: throw AssemblyError("undefined subroutine ${stmt.target}")
         if(sub.shouldSaveX()) {
             val regSaveOnStack = sub.asmAddress==null       // rom-routines don't require registers to be saved on stack, normal subroutines do because they can contain nested calls
-            val (keepAonEntry: Boolean, keepAonReturn: Boolean) = sub.shouldKeepA()
-
             if(regSaveOnStack)
-                asmgen.restoreRegisterStack(CpuRegister.X, keepAonReturn)
+                asmgen.restoreRegisterStack(CpuRegister.X, sub.shouldKeepA().saveOnReturn)
             else
                 asmgen.restoreRegisterLocal(CpuRegister.X)
         }
     }
 
     internal fun translateFunctionCall(stmt: IFunctionCall) {
-        // Output only the code to setup the parameters and perform the actual call
+        // 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)
@@ -64,7 +64,7 @@ internal class FunctionCallAsmGen(private val program: Program, private val asmg
                     argumentViaVariable(sub, arg.first, arg.second)
                 }
             } else {
-                // via registers
+                require(sub.isAsmSubroutine)
                 if(sub.parameters.size==1) {
                     // just a single parameter, no risk of clobbering registers
                     argumentViaRegister(sub, IndexedValue(0, sub.parameters.single()), stmt.args[0])
@@ -118,16 +118,14 @@ internal class FunctionCallAsmGen(private val program: Program, private val asmg
             // 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)
+                throw AssemblyError("can only reliably inline asmsub routines at this time")
+
             asmgen.out("  \t; inlined routine follows: ${sub.name}")
-            val statements = sub.statements.filter { it !is ParameterVarDecl && it !is Directive }
-            statements.forEach {
-                if(it is Return) {
-                    asmgen.translate(it, false)     // don't use RTS for the inlined return statement
-                } else {
-                    if(!sub.inline || it !is VarDecl)
-                        asmgen.translate(it)
-                }
-            }
+            val assembly = sub.statements.single() as InlineAssembly
+            asmgen.translate(assembly)
             asmgen.out("  \t; inlined routine end: ${sub.name}")
         }
 
@@ -137,14 +135,25 @@ internal class FunctionCallAsmGen(private val program: Program, private val asmg
     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
@@ -159,11 +168,11 @@ internal class FunctionCallAsmGen(private val program: Program, private val asmg
                     argForCarry = argi
                 }
                 argi.value.second.statusflag != null -> throw AssemblyError("can only use Carry as status flag parameter")
-                argi.value.second.registerOrPair in setOf(RegisterOrPair.X, RegisterOrPair.AX, RegisterOrPair.XY) -> {
+                argi.value.second.registerOrPair in arrayOf(RegisterOrPair.X, RegisterOrPair.AX, RegisterOrPair.XY) -> {
                     require(argForXregister==null)
                     argForXregister = argi
                 }
-                argi.value.second.registerOrPair in setOf(RegisterOrPair.A, RegisterOrPair.AY) -> {
+                argi.value.second.registerOrPair in arrayOf(RegisterOrPair.A, RegisterOrPair.AY) -> {
                     require(argForAregister == null)
                     argForAregister = argi
                 }
@@ -254,7 +263,7 @@ internal class FunctionCallAsmGen(private val program: Program, private val asmg
         val valueIDt = value.inferType(program)
         if(!valueIDt.isKnown)
             throw AssemblyError("unknown dt")
-        val valueDt = valueIDt.typeOrElse(DataType.UNDEFINED)
+        val valueDt = valueIDt.getOr(DataType.UNDEFINED)
         if(!isArgumentTypeCompatible(valueDt, parameter.value.type))
             throw AssemblyError("argument type incompatible")
 
@@ -267,7 +276,7 @@ internal class FunctionCallAsmGen(private val program: Program, private val asmg
         val valueIDt = value.inferType(program)
         if(!valueIDt.isKnown)
             throw AssemblyError("unknown dt")
-        val valueDt = valueIDt.typeOrElse(DataType.UNDEFINED)
+        val valueDt = valueIDt.getOr(DataType.UNDEFINED)
         if(!isArgumentTypeCompatible(valueDt, parameter.value.type))
             throw AssemblyError("argument type incompatible")
 
@@ -327,7 +336,7 @@ internal class FunctionCallAsmGen(private val program: Program, private val asmg
                     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)
+                        AsmAssignTarget.fromRegisters(register, false, sub, program, asmgen)
                 val src = if(valueDt in PassByReferenceDatatypes) {
                     if(value is IdentifierReference) {
                         val addr = AddressOf(value, Position.DUMMY)

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

@@ -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.compiler.target.AssemblyError
 
 
 internal class PostIncrDecrAsmGen(private val program: Program, private val asmgen: AsmGen) {
@@ -15,11 +15,11 @@ internal class PostIncrDecrAsmGen(private val program: Program, private val asmg
         val targetIdent = stmt.target.identifier
         val targetMemory = stmt.target.memoryAddress
         val targetArrayIdx = stmt.target.arrayindexed
-        val scope = stmt.definingSubroutine()
+        val scope = stmt.definingSubroutine
         when {
             targetIdent!=null -> {
                 val what = asmgen.asmVariableName(targetIdent)
-                when (stmt.target.inferType(program).typeOrElse(DataType.UNDEFINED)) {
+                when (stmt.target.inferType(program).getOr(DataType.UNDEFINED)) {
                     in ByteDatatypes -> asmgen.out(if (incr) "  inc  $what" else "  dec  $what")
                     in WordDatatypes -> {
                         if(incr)
@@ -65,7 +65,7 @@ internal class PostIncrDecrAsmGen(private val program: Program, private val asmg
             }
             targetArrayIdx!=null -> {
                 val asmArrayvarname = asmgen.asmVariableName(targetArrayIdx.arrayvar)
-                val elementDt = targetArrayIdx.inferType(program).typeOrElse(DataType.UNDEFINED)
+                val elementDt = targetArrayIdx.inferType(program).getOr(DataType.UNDEFINED)
                 val constIndex = targetArrayIdx.indexer.constIndex()
                 if(constIndex!=null) {
                     val indexValue = constIndex * program.memsizer.memorySize(elementDt)

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

@@ -1,11 +1,11 @@
 package prog8.compiler.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.compilerinterface.IMemSizer
+import prog8.compiler.target.AssemblyError
 import prog8.compiler.target.cpu6502.codegen.AsmGen
 
 
@@ -41,11 +41,12 @@ internal class AsmAssignTarget(val kind: TargetStorageKind,
 {
     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 asmVarname: String by lazy {
+        if (array == null)
             variableAsmName!!
         else
             asmgen.asmVariableName(array.arrayvar)
+    }
 
     lateinit var origAssign: AsmAssignment
 
@@ -59,23 +60,23 @@ internal class AsmAssignTarget(val kind: TargetStorageKind,
             val idt = inferType(program)
             if(!idt.isKnown)
                 throw AssemblyError("unknown dt")
-            val dt = idt.typeOrElse(DataType.UNDEFINED)
+            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)
+                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 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 +94,7 @@ 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)
                 }
     }
 }
@@ -132,7 +133,7 @@ internal class AsmAssignSource(val kind: SourceStorageKind,
                 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 dt = value.inferType(program).typeOrElse(DataType.UNDEFINED)
+                    val dt = value.inferType(program).getOr(DataType.UNDEFINED)
                     val varName=asmgen.asmVariableName(value)
                     // special case: "cx16.r[0-15]" are 16-bits virtual registers of the commander X16 system
                     if(dt == DataType.UWORD && varName.lowercase().startsWith("cx16.r")) {
@@ -147,7 +148,7 @@ internal class AsmAssignSource(val kind: SourceStorageKind,
                     AsmAssignSource(SourceStorageKind.MEMORY, program, asmgen, DataType.UBYTE, memory = value)
                 }
                 is ArrayIndexedExpression -> {
-                    val dt = value.inferType(program).typeOrElse(DataType.UNDEFINED)
+                    val dt = value.inferType(program).getOr(DataType.UNDEFINED)
                     AsmAssignSource(SourceStorageKind.ARRAY, program, asmgen, dt, array = value)
                 }
                 is FunctionCall -> {
@@ -162,7 +163,7 @@ internal class AsmAssignSource(val kind: SourceStorageKind,
                             val returnType = value.inferType(program)
                             if(!returnType.isKnown)
                                 throw AssemblyError("unknown dt")
-                            AsmAssignSource(SourceStorageKind.EXPRESSION, program, asmgen, returnType.typeOrElse(DataType.UNDEFINED), expression = value)
+                            AsmAssignSource(SourceStorageKind.EXPRESSION, program, asmgen, returnType.getOr(DataType.UNDEFINED), expression = value)
                         }
                         else -> {
                             throw AssemblyError("weird call")
@@ -173,7 +174,7 @@ internal class AsmAssignSource(val kind: SourceStorageKind,
                     val dt = value.inferType(program)
                     if(!dt.isKnown)
                         throw AssemblyError("unknown dt")
-                    AsmAssignSource(SourceStorageKind.EXPRESSION, program, asmgen, dt.typeOrElse(DataType.UNDEFINED), expression = value)
+                    AsmAssignSource(SourceStorageKind.EXPRESSION, program, asmgen, dt.getOr(DataType.UNDEFINED), expression = value)
                 }
             }
         }
@@ -205,7 +206,7 @@ internal class AsmAssignment(val source: AsmAssignSource,
                              val position: Position) {
 
     init {
-        if(target.register !in setOf(RegisterOrPair.XY, RegisterOrPair.AX, RegisterOrPair.AY))
+        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"

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

@@ -5,12 +5,12 @@ 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.AssemblyError
 import prog8.compiler.target.cpu6502.codegen.AsmGen
 import prog8.compiler.target.cpu6502.codegen.ExpressionsAsmGen
+import prog8.compilerinterface.BuiltinFunctions
+import prog8.compilerinterface.CpuType
+import prog8.compilerinterface.builtinFunctionReturnType
 
 
 internal class AssignmentAsmGen(private val program: Program, private val asmgen: AsmGen,
@@ -33,6 +33,11 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
     }
 
     fun translateNormalAssignment(assign: AsmAssignment) {
+        if(assign.isAugmentable) {
+            augmentableAsmGen.translate(assign)
+            return
+        }
+
         when(assign.source.kind) {
             SourceStorageKind.LITERALNUMBER -> {
                 // simple case: assign a constant number
@@ -171,13 +176,13 @@ 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")
                                         }
@@ -217,7 +222,7 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                                     val returntype = builtinFunctionReturnType(sub.name, value.args, program)
                                     if(!returntype.isKnown)
                                         throw AssemblyError("unknown dt")
-                                    when(returntype.typeOrElse(DataType.UNDEFINED)) {
+                                    when(returntype.getOr(DataType.UNDEFINED)) {
                                         in ByteDatatypes -> assignRegisterByte(assign.target, CpuRegister.A)            // function's byte result is in A
                                         in WordDatatypes -> assignRegisterpairWord(assign.target, RegisterOrPair.AY)    // function's word result is in AY
                                         DataType.STR -> {
@@ -249,30 +254,40 @@ 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
+                        ))
+                        when(value.operator) {
+                            "+" -> {}
+                            "-" -> augmentableAsmGen.inplaceNegate(assign.target, assign.target.datatype)
+                            "~" -> augmentableAsmGen.inplaceInvert(assign.target, assign.target.datatype)
+                            "not" -> augmentableAsmGen.inplaceBooleanNot(assign.target, assign.target.datatype)
+                            else -> throw AssemblyError("invalid prefix operator")
+                        }
+                    }
                     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)
+                        // TODO FIX 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)
-                        assignStackValue(assign.target)
+                        if(assign.target.kind!=TargetStorageKind.STACK || assign.target.datatype != assign.source.datatype)
+                            assignStackValue(assign.target)
                     }
                 }
             }
             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)
             }
         }
     }
@@ -299,7 +314,7 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
         val valueIDt = value.inferType(program)
         if(!valueIDt.isKnown)
             throw AssemblyError("unknown dt")
-        val valueDt = valueIDt.typeOrElse(DataType.UNDEFINED)
+        val valueDt = valueIDt.getOr(DataType.UNDEFINED)
         if(valueDt==targetDt)
             throw AssemblyError("type cast to identical dt should have been removed")
 
@@ -364,16 +379,16 @@ 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)
@@ -398,15 +413,15 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                 RegisterOrPair.A,
                 RegisterOrPair.X,
                 RegisterOrPair.Y -> {
-                    // 'cast' a ubyte value to a byte register; no cast needed at all
-                    return assignExpressionToRegister(value, target.register)
+                    // 'cast' an ubyte value to a byte register; no cast needed at all
+                    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 -> {}
             }
@@ -424,19 +439,15 @@ 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
+        // No more special optmized cases yet. Do the rest via more complex evaluation
         // 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)
+        asmgen.assignExpressionTo(origTypeCastExpression, target)
     }
 
     private fun assignCastViaLsbFunc(value: Expression, target: AsmAssignTarget) {
@@ -447,7 +458,7 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
         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")
@@ -954,7 +965,8 @@ 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")
@@ -1359,9 +1371,11 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
     }
 
     internal fun assignRegisterByte(target: AsmAssignTarget, register: CpuRegister) {
-        // we make an exception in the type check for assigning something to a cx16 virtual register
-        if(target.register !in Cx16VirtualRegisters) {
-            if(target.kind==TargetStorageKind.VARIABLE) {
+        // we make an exception in the type check for assigning something to a cx16 virtual register, or a register pair
+        // 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) {
                 val parts = target.asmVarname.split('.')
                 if (parts.size != 2 || parts[0] != "cx16")
                     require(target.datatype in ByteDatatypes)
@@ -1457,7 +1471,7 @@ 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")
 
@@ -1584,7 +1598,7 @@ 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)
@@ -2155,9 +2169,9 @@ 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)
     }
@@ -2169,8 +2183,8 @@ 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/compiler/target/cpu6502/codegen/assignment/AugmentableAssignmentAsmGen.kt

@@ -5,10 +5,10 @@ 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.AssemblyError
 import prog8.compiler.target.cpu6502.codegen.AsmGen
 import prog8.compiler.target.cpu6502.codegen.ExpressionsAsmGen
+import prog8.compilerinterface.CpuType
 
 internal class AugmentableAssignmentAsmGen(private val program: Program,
                                            private val assignmentAsmGen: AssignmentAsmGen,
@@ -25,7 +25,7 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                 val itype = value.inferType(program)
                 if(!itype.isKnown)
                     throw AssemblyError("unknown dt")
-                val type = itype.typeOrElse(DataType.UNDEFINED)
+                val type = itype.getOr(DataType.UNDEFINED)
                 when (value.operator) {
                     "+" -> {}
                     "-" -> inplaceNegate(assign.target, type)
@@ -181,8 +181,9 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                         }
                     }
                     else -> {
-                        asmgen.translateExpression(memory.addressExpression)
-                        asmgen.out("  jsr  prog8_lib.read_byte_from_address_on_stack |  sta  P8ZP_SCRATCH_B1")
+                        // TODO OTHER EVALUATION HERE, don't use the estack
+                        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")      // TODO don't use estack to transfer the address to read from
                         when {
                             valueLv != null -> inplaceModification_byte_litval_to_variable("P8ZP_SCRATCH_B1", DataType.UBYTE, operator, valueLv.toInt())
                             ident != null -> inplaceModification_byte_variable_to_variable("P8ZP_SCRATCH_B1", DataType.UBYTE, operator, ident)
@@ -193,7 +194,7 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                             }
                             else -> inplaceModification_byte_value_to_variable("P8ZP_SCRATCH_B1", DataType.UBYTE, operator, value)
                         }
-                        asmgen.out("  lda  P8ZP_SCRATCH_B1 |  jsr  prog8_lib.write_byte_to_address_on_stack | inx")
+                        asmgen.out("  lda  P8ZP_SCRATCH_B1 |  jsr  prog8_lib.write_byte_to_address_on_stack | inx")  // TODO don't use estack to transfer the address to read from
                     }
                 }
             }
@@ -246,19 +247,37 @@ 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)
@@ -280,7 +299,7 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
             val childIDt = value.expression.inferType(program)
             if(!childIDt.isKnown)
                 throw AssemblyError("unknown dt")
-            val childDt = childIDt.typeOrElse(DataType.UNDEFINED)
+            val childDt = childIDt.getOr(DataType.UNDEFINED)
             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.)
@@ -293,7 +312,6 @@ 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 (ptrOnZp, sourceName) = asmgen.loadByteFromPointerIntoA(pointervar)
         when (operator) {
             // note: ** (power) operator requires floats.
             "+" -> asmgen.out("  clc |  adc  P8ZP_SCRATCH_B1")
@@ -324,15 +342,13 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
             "^", "xor" -> asmgen.out(" eor  P8ZP_SCRATCH_B1")
             else -> throw AssemblyError("invalid operator for in-place modification $operator")
         }
-        if(ptrOnZp)
-            asmgen.out("  sta  ($sourceName),y")
-        else
-            asmgen.out("  sta  (P8ZP_SCRATCH_W1),y")
+        val sourceName = asmgen.loadByteFromPointerIntoA(pointervar)
+        asmgen.out("  sta  ($sourceName),y")
     }
 
     private fun inplaceModification_byte_variable_to_pointer(pointervar: IdentifierReference, operator: String, value: IdentifierReference) {
         val otherName = asmgen.asmVariableName(value)
-        val (ptrOnZp, sourceName) = asmgen.loadByteFromPointerIntoA(pointervar)
+        val sourceName = asmgen.loadByteFromPointerIntoA(pointervar)
 
         when (operator) {
             // note: ** (power) operator requires floats.
@@ -364,105 +380,72 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
             "^", "xor" -> asmgen.out(" eor  $otherName")
             else -> throw AssemblyError("invalid operator for in-place modification $operator")
         }
-        if(ptrOnZp)
-            asmgen.out("  sta  ($sourceName),y")
-        else
-            asmgen.out("  sta  (P8ZP_SCRATCH_W1),y")
+        asmgen.out("  sta  ($sourceName),y")
     }
 
     private fun inplaceModification_byte_litval_to_pointer(pointervar: IdentifierReference, operator: String, value: Int) {
         when (operator) {
             // note: ** (power) operator requires floats.
             "+" -> {
-                val (ptrOnZp, sourceName) = asmgen.loadByteFromPointerIntoA(pointervar)
-                asmgen.out(" clc |  adc  #$value")
-                if(ptrOnZp)
-                    asmgen.out("  sta  ($sourceName),y")
-                else
-                    asmgen.out("  sta  (P8ZP_SCRATCH_W1),y")
+                val sourceName = asmgen.loadByteFromPointerIntoA(pointervar)
+                asmgen.out("  clc |  adc  #$value")
+                asmgen.out("  sta  ($sourceName),y")
             }
             "-" -> {
-                val (ptrOnZp, sourceName) = asmgen.loadByteFromPointerIntoA(pointervar)
-                asmgen.out(" sec |  sbc  #$value")
-                if(ptrOnZp)
-                    asmgen.out("  sta  ($sourceName),y")
-                else
-                    asmgen.out("  sta  (P8ZP_SCRATCH_W1),y")
+                val sourceName = asmgen.loadByteFromPointerIntoA(pointervar)
+                asmgen.out("  sec |  sbc  #$value")
+                asmgen.out("  sta  ($sourceName),y")
             }
             "*" -> {
-                val (ptrOnZp, sourceName) = asmgen.loadByteFromPointerIntoA(pointervar)
+                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")
-                if(ptrOnZp)
-                    asmgen.out("  sta  ($sourceName),y")
-                else
-                    asmgen.out("  sta  (P8ZP_SCRATCH_W1),y")
+                asmgen.out("  sta  ($sourceName),y")
             }
             "/" -> {
-                val (ptrOnZp, sourceName) = asmgen.loadByteFromPointerIntoA(pointervar)
+                val sourceName = asmgen.loadByteFromPointerIntoA(pointervar)
                 if(value==0)
                     throw AssemblyError("division by zero")
                 asmgen.out("  ldy  #$value |  jsr  math.divmod_ub_asm |  tya |  ldy  #0")
-                if(ptrOnZp)
-                    asmgen.out("  sta  ($sourceName),y")
-                else
-                    asmgen.out("  sta  (P8ZP_SCRATCH_W1),y")
+                asmgen.out("  sta  ($sourceName),y")
             }
             "%" -> {
-                val (ptrOnZp, sourceName) = asmgen.loadByteFromPointerIntoA(pointervar)
+                val sourceName = asmgen.loadByteFromPointerIntoA(pointervar)
                 if(value==0)
                     throw AssemblyError("division by zero")
                 asmgen.out("  ldy  #$value |  jsr  math.divmod_ub_asm |  ldy  #0")
-                if(ptrOnZp)
-                    asmgen.out("  sta  ($sourceName),y")
-                else
-                    asmgen.out("  sta  (P8ZP_SCRATCH_W1),y")
+                asmgen.out("  sta  ($sourceName),y")
             }
             "<<" -> {
                 if (value > 0) {
-                    val (ptrOnZp, sourceName) = asmgen.loadByteFromPointerIntoA(pointervar)
+                    val sourceName = asmgen.loadByteFromPointerIntoA(pointervar)
                     repeat(value) { asmgen.out(" asl  a") }
-                    if(ptrOnZp)
-                        asmgen.out("  sta  ($sourceName),y")
-                    else
-                        asmgen.out("  sta  (P8ZP_SCRATCH_W1),y")
+                    asmgen.out("  sta  ($sourceName),y")
                 }
             }
             ">>" -> {
                 if (value > 0) {
-                    val (ptrOnZp, sourceName) = asmgen.loadByteFromPointerIntoA(pointervar)
+                    val sourceName = asmgen.loadByteFromPointerIntoA(pointervar)
                     repeat(value) { asmgen.out(" lsr  a") }
-                    if(ptrOnZp)
-                        asmgen.out("  sta  ($sourceName),y")
-                    else
-                        asmgen.out("  sta  (P8ZP_SCRATCH_W1),y")
+                    asmgen.out("  sta  ($sourceName),y")
                 }
             }
             "&", "and" -> {
-                val (ptrOnZp, sourceName) = asmgen.loadByteFromPointerIntoA(pointervar)
-                asmgen.out(" and  #$value")
-                if(ptrOnZp)
-                    asmgen.out("  sta  ($sourceName),y")
-                else
-                    asmgen.out("  sta  (P8ZP_SCRATCH_W1),y")
+                val sourceName = asmgen.loadByteFromPointerIntoA(pointervar)
+                asmgen.out("  and  #$value")
+                asmgen.out("  sta  ($sourceName),y")
             }
             "|", "or" -> {
-                val (ptrOnZp, sourceName) = asmgen.loadByteFromPointerIntoA(pointervar)
-                asmgen.out(" ora  #$value")
-                if(ptrOnZp)
-                    asmgen.out("  sta  ($sourceName),y")
-                else
-                    asmgen.out("  sta  (P8ZP_SCRATCH_W1),y")
+                val sourceName = asmgen.loadByteFromPointerIntoA(pointervar)
+                asmgen.out("  ora  #$value")
+                asmgen.out("  sta  ($sourceName),y")
             }
             "^", "xor" -> {
-                val (ptrOnZp, sourceName) = asmgen.loadByteFromPointerIntoA(pointervar)
-                asmgen.out(" eor  #$value")
-                if(ptrOnZp)
-                    asmgen.out("  sta  ($sourceName),y")
-                else
-                    asmgen.out("  sta  (P8ZP_SCRATCH_W1),y")
+                val sourceName = asmgen.loadByteFromPointerIntoA(pointervar)
+                asmgen.out("  eor  #$value")
+                asmgen.out("  sta  ($sourceName),y")
             }
             else -> throw AssemblyError("invalid operator for in-place modification $operator")
         }
@@ -1010,8 +993,7 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
 
     private fun inplaceModification_word_variable_to_variable(name: String, dt: DataType, operator: String, ident: IdentifierReference) {
         val otherName = asmgen.asmVariableName(ident)
-        val valueDt = ident.targetVarDecl(program)!!.datatype
-        when (valueDt) {
+        when (val valueDt = ident.targetVarDecl(program)!!.datatype) {
             in ByteDatatypes -> {
                 // the other variable is a BYTE type so optimize for that
                 when (operator) {
@@ -1255,7 +1237,7 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
         val valueiDt = value.inferType(program)
         if(!valueiDt.isKnown)
             throw AssemblyError("unknown dt")
-        val valueDt = valueiDt.typeOrElse(DataType.UNDEFINED)
+        val valueDt = valueiDt.getOr(DataType.UNDEFINED)
 
         fun multiplyVarByWordInAY() {
             asmgen.out("""
@@ -1697,7 +1679,7 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
         if (innerCastDt == null) {
             // simple typecast where the value is the target
             when (target.datatype) {
-                DataType.UBYTE, DataType.BYTE -> { /* byte target can't be casted to anything else at all */ }
+                DataType.UBYTE, DataType.BYTE -> { /* byte target can't be typecasted to anything else at all */ }
                 DataType.UWORD, DataType.WORD -> {
                     when (outerCastDt) {
                         DataType.UBYTE, DataType.BYTE -> {
@@ -1742,7 +1724,7 @@ 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) {
@@ -1767,15 +1749,12 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                                     sta  $addr""")
                             }
                             is IdentifierReference -> {
-                                val (ptrOnZp, sourceName) = asmgen.loadByteFromPointerIntoA(mem.addressExpression as IdentifierReference)
+                                val sourceName = asmgen.loadByteFromPointerIntoA(mem.addressExpression as IdentifierReference)
                                 asmgen.out("""
                                     beq  +
                                     lda  #1
 +                                   eor  #1""")
-                                if(ptrOnZp)
-                                    asmgen.out("  sta  ($sourceName),y")
-                                else
-                                    asmgen.out("  sta  (P8ZP_SCRATCH_W1),y")
+                                asmgen.out("  sta  ($sourceName),y")
                             }
                             else -> {
                                 asmgen.assignExpressionToVariable(mem.addressExpression, "P8ZP_SCRATCH_W2", DataType.UWORD, target.scope)
@@ -1789,9 +1768,30 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                             }
                         }
                     }
-                    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("missing codegen for byte stack not")
+                    else -> throw AssemblyError("missing codegen for in-place not of ubyte ${target.kind}")
                 }
             }
             DataType.UWORD -> {
@@ -1807,17 +1807,56 @@ 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 -> TODO()
+                            else -> throw AssemblyError("invalid reg dt for word not")
+                        }
+                    }
+                    TargetStorageKind.MEMORY -> TODO("no asm gen for uword-memory not")
+                    TargetStorageKind.STACK -> TODO("missing codegen for word stack not")
+                    else -> throw AssemblyError("missing codegen 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) {
@@ -1838,12 +1877,9 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                                     sta  $addr""")
                             }
                             is IdentifierReference -> {
-                                val (ptrOnZp, sourceName) = asmgen.loadByteFromPointerIntoA(memory.addressExpression as IdentifierReference)
+                                val sourceName = asmgen.loadByteFromPointerIntoA(memory.addressExpression as IdentifierReference)
                                 asmgen.out("  eor  #255")
-                                if(ptrOnZp)
-                                    asmgen.out("  sta  ($sourceName),y")
-                                else
-                                    asmgen.out("  sta  (P8ZP_SCRATCH_W1),y")
+                                asmgen.out("  sta  ($sourceName),y")
                             }
                             else -> {
                                 asmgen.assignExpressionToVariable(memory.addressExpression, "P8ZP_SCRATCH_W2", DataType.UWORD, target.scope)
@@ -1855,9 +1891,16 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                             }
                         }
                     }
-                    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("missing codegen for byte stack invert")
+                    else -> throw AssemblyError("missing codegen for in-place invert ubyte for ${target.kind}")
                 }
             }
             DataType.UWORD -> {
@@ -1871,17 +1914,27 @@ 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 -> {
+                                TODO("codegen for cx16 word register invert")
+                            }
+                            else -> throw AssemblyError("invalid reg dt for word invert")
+                        }
+                    }
+                    TargetStorageKind.MEMORY -> TODO("no asm gen for uword-memory invert")
+                    TargetStorageKind.STACK -> TODO("missing codegen for word stack invert")
+                    else -> throw AssemblyError("missing codegen 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) {
@@ -1892,10 +1945,17 @@ 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 -> asmgen.out("  sta  P8ZP_SCRATCH_B1 |  lda  #0 |  sec |  sbc  P8ZP_SCRATCH_B1")
+                            RegisterOrPair.X -> asmgen.out("  stx  P8ZP_SCRATCH_B1 |  lda  #0 |  sec |  sbc  P8ZP_SCRATCH_B1 |  tax")
+                            RegisterOrPair.Y -> asmgen.out("  sty  P8ZP_SCRATCH_B1 |  lda  #0 |  sec |  sbc  P8ZP_SCRATCH_B1 |  tay")
+                            else -> throw AssemblyError("invalid reg dt for byte negate")
+                        }
+                    }
+                    TargetStorageKind.MEMORY -> TODO("can't in-place negate memory ubyte")
+                    TargetStorageKind.STACK -> TODO("missing codegen for byte stack negate")
+                    else -> throw AssemblyError("missing codegen for in-place negate byte array")
                 }
             }
             DataType.WORD -> {
@@ -1910,10 +1970,55 @@ 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 -> {
+                                TODO("codegen for cx16 word register negate")
+                            }
+                            else -> throw AssemblyError("invalid reg dt for word neg")
+                        }
+                    }
+                    TargetStorageKind.MEMORY -> TODO("no asm gen for word memory negate")
+                    TargetStorageKind.STACK -> TODO("missing codegen for word stack negate")
+                    else -> throw AssemblyError("missing codegen for in-place negate word array")
                 }
             }
             DataType.FLOAT -> {
@@ -1926,9 +2031,10 @@ 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.REGISTER -> TODO("missing codegen for float reg negate")
+                    TargetStorageKind.MEMORY -> TODO("missing codegen for float memory negate")
+                    TargetStorageKind.STACK -> TODO("missing codegen for stack float negate")
+                    else -> throw AssemblyError("weird target kind for inplace negate float ${target.kind}")
                 }
             }
             else -> throw AssemblyError("negate of invalid type")

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

@@ -1,12 +1,13 @@
 package prog8.compiler.target.cx16
 
-import prog8.compiler.*
-import prog8.compiler.target.CpuType
-import prog8.compiler.target.IMachineDefinition
 import prog8.compiler.target.c64.C64MachineDefinition
+import prog8.compiler.target.cbm.viceMonListPostfix
+import prog8.compilerinterface.*
 import java.io.IOException
+import java.nio.file.Path
 
-internal object CX16MachineDefinition: IMachineDefinition {
+
+object CX16MachineDefinition: IMachineDefinition {
 
     override val cpu = CpuType.CPU65c02
 
@@ -32,10 +33,28 @@ internal object CX16MachineDefinition: IMachineDefinition {
             emptyList()
     }
 
-    override fun launchEmulator(programName: String) {
-        for(emulator in listOf("x16emu")) {
+    override fun launchEmulator(selectedEmulator: Int, programNameWithPath: Path) {
+        val emulatorName: String
+        val extraArgs: List<String>
+
+        when(selectedEmulator) {
+            1 -> {
+                emulatorName = "x16emu"
+                extraArgs = emptyList()
+            }
+            2 -> {
+                emulatorName = "box16"
+                extraArgs = listOf("-sym", "${programNameWithPath}.$viceMonListPostfix")
+            }
+            else -> {
+                System.err.println("Cx16 target only supports x16emu and box16 emulators.")
+                return
+            }
+        }
+
+        for(emulator in listOf(emulatorName)) {
             println("\nStarting Commander X16 emulator $emulator...")
-            val cmdline = listOf(emulator, "-scale", "2", "-run", "-prg", "$programName.prg")
+            val cmdline = listOf(emulator, "-scale", "2", "-run", "-prg", "${programNameWithPath}.prg") + extraArgs
             val processb = ProcessBuilder(cmdline).inheritIO()
             val process: Process
             try {
@@ -68,7 +87,7 @@ internal object CX16MachineDefinition: IMachineDefinition {
             "rmb", "smb", "stp", "wai")
 
 
-    internal class CX16Zeropage(options: CompilationOptions) : Zeropage(options) {
+    class CX16Zeropage(options: CompilationOptions) : Zeropage(options) {
 
         override val SCRATCH_B1 = 0x7a      // temp storage for a single byte
         override val SCRATCH_REG = 0x7b     // temp storage for a register, must be B1+1
@@ -77,38 +96,29 @@ internal object CX16MachineDefinition: IMachineDefinition {
 
 
         init {
-            if (options.floats && options.zeropage !in setOf(ZeropageType.BASICSAFE, ZeropageType.DONTUSE ))
-                throw CompilerException("when floats are enabled, zero page type should be 'basicsafe' or 'dontuse'")
+            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(0x22..0xff)
-                    free.removeAll(listOf(SCRATCH_B1, SCRATCH_REG, SCRATCH_W1, SCRATCH_W1 + 1, SCRATCH_W2, SCRATCH_W2 + 1))
                 }
                 ZeropageType.KERNALSAFE -> {
                     free.addAll(0x22..0x7f)
                     free.addAll(0xa9..0xff)
-                    free.removeAll(listOf(SCRATCH_B1, SCRATCH_REG, SCRATCH_W1, SCRATCH_W1 + 1, SCRATCH_W2, SCRATCH_W2 + 1))
                 }
                 ZeropageType.BASICSAFE -> {
                     free.addAll(0x22..0x7f)
-                    free.removeAll(listOf(SCRATCH_B1, SCRATCH_REG, SCRATCH_W1, SCRATCH_W1 + 1, SCRATCH_W2, SCRATCH_W2 + 1))
                 }
                 ZeropageType.DONTUSE -> {
                     free.clear() // don't use zeropage at all
                 }
-                else -> throw CompilerException("for this machine target, zero page type 'floatsafe' is not available. ${options.zeropage}")
+                else -> throw InternalCompilerException("for this machine target, zero page type 'floatsafe' is not available. ${options.zeropage}")
             }
 
-            require(SCRATCH_B1 !in free)
-            require(SCRATCH_REG !in free)
-            require(SCRATCH_W1 !in free)
-            require(SCRATCH_W2 !in free)
-
-            for (reserved in options.zpReserved)
-                reserve(reserved)
+            removeReservedFromFreePool()
         }
     }
 }

codeGeneration/test/AsmGenTests.kt

@@ -1,35 +1,33 @@
-package prog8tests
+package prog8tests.asmgen
 
 import org.hamcrest.MatcherAssert.assertThat
 import org.hamcrest.Matchers.equalTo
-import org.junit.jupiter.api.Disabled
 import org.junit.jupiter.api.Test
 import org.junit.jupiter.api.TestInstance
-import prog8.ast.IBuiltinFunctions
-import prog8.ast.IMemSizer
 import prog8.ast.Module
 import prog8.ast.Program
-import prog8.ast.base.*
-import prog8.ast.expressions.*
+import prog8.ast.base.DataType
+import prog8.ast.base.Position
+import prog8.ast.base.RegisterOrPair
+import prog8.ast.base.VarDeclType
+import prog8.ast.expressions.AddressOf
+import prog8.ast.expressions.IdentifierReference
+import prog8.ast.expressions.NumericLiteralValue
 import prog8.ast.statements.*
-import prog8.compiler.*
 import prog8.compiler.target.C64Target
 import prog8.compiler.target.c64.C64MachineDefinition
 import prog8.compiler.target.cpu6502.codegen.AsmGen
+import prog8.compilerinterface.*
+import prog8.parser.SourceCode
+import prog8tests.asmgen.helpers.DummyFunctions
+import prog8tests.asmgen.helpers.DummyMemsizer
+import prog8tests.asmgen.helpers.DummyStringEncoder
+import prog8tests.asmgen.helpers.ErrorReporterForTests
 import java.nio.file.Path
 
+
 @TestInstance(TestInstance.Lifecycle.PER_CLASS)
 class TestAsmGen6502 {
-    private class DummyFunctions: IBuiltinFunctions {
-        override val names: Set<String> = emptySet()
-        override val purefunctionNames: Set<String> = emptySet()
-        override fun constValue(name: String, args: List<Expression>, position: Position, memsizer: IMemSizer): NumericLiteralValue? = null
-        override fun returnType(name: String, args: MutableList<Expression>) = InferredTypes.InferredType.unknown()
-    }
-
-    private class DummyMemsizer: IMemSizer {
-        override fun memorySize(dt: DataType): Int = 0
-    }
 
     private fun createTestProgram(): Program {
         /*
@@ -70,23 +68,23 @@ locallabel:
         val assign8 = Assignment(tgt, AddressOf(IdentifierReference(listOf("main","label_outside"), Position.DUMMY), Position.DUMMY), Position.DUMMY)
 
         val statements = mutableListOf(varInSub, var2InSub, labelInSub, assign1, assign2, assign3, assign4, assign5, assign6, assign7, assign8)
-        val subroutine = Subroutine("start", emptyList(), emptyList(), emptyList(), emptyList(), emptySet(), null, false, false, statements, Position.DUMMY)
+        val subroutine = Subroutine("start", mutableListOf(), emptyList(), emptyList(), emptyList(), emptySet(), null, false, false, statements, Position.DUMMY)
         val labelInBlock = Label("label_outside", Position.DUMMY)
         val varInBlock = VarDecl(VarDeclType.VAR, DataType.UWORD, ZeropageWish.DONTCARE, null, "var_outside", null, false, false, false, Position.DUMMY)
         val block = Block("main", null, mutableListOf(labelInBlock, varInBlock, subroutine), false, Position.DUMMY)
 
-        val module = Module("test", mutableListOf(block), Position.DUMMY, false, Path.of(""))
-        module.linkParents(ParentSentinel)
-        val program = Program("test", mutableListOf(module), DummyFunctions(), DummyMemsizer())
-        module.program = program
+        val module = Module(mutableListOf(block), Position.DUMMY, SourceCode.Generated("test"))
+        val program = Program("test", DummyFunctions, DummyMemsizer, DummyStringEncoder)
+            .addModule(module)
+        module.linkIntoProgram(program)
         return program
     }
 
     private fun createTestAsmGen(program: Program): AsmGen {
-        val errors = ErrorReporter()
+        val errors = ErrorReporterForTests()
         val options = CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.FULL, emptyList(), false, true, C64Target)
         val zp = C64MachineDefinition.C64Zeropage(options)
-        val asmgen = AsmGen(program, errors, zp, options, C64Target, Path.of("."))
+        val asmgen = AsmGen(program, errors, zp, options, C64Target, Path.of(""))
         return asmgen
     }
 
@@ -108,7 +106,7 @@ locallabel:
     fun testSymbolNameFromVarIdentifier() {
         val program = createTestProgram()
         val asmgen = createTestAsmGen(program)
-        val sub = program.entrypoint()
+        val sub = program.entrypoint
 
         // local variable
         val localvarIdent = sub.statements.filterIsInstance<Assignment>().first { it.value is IdentifierReference }.value as IdentifierReference
@@ -132,7 +130,7 @@ locallabel:
     fun testSymbolNameFromLabelIdentifier() {
         val program = createTestProgram()
         val asmgen = createTestAsmGen(program)
-        val sub = program.entrypoint()
+        val sub = program.entrypoint
 
         // local label
         val localLabelIdent = (sub.statements.filterIsInstance<Assignment>().first { (it.value as? AddressOf)?.identifier?.nameInSource==listOf("locallabel") }.value as AddressOf).identifier

codeGeneration/test/helpers/Dummies.kt

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

codeGeneration/test/helpers/ErrorReporterForTests.kt

@@ -0,0 +1,30 @@
+package prog8tests.asmgen.helpers
+
+import prog8.ast.base.Position
+import prog8.compilerinterface.IErrorReporter
+
+internal class ErrorReporterForTests(private val throwExceptionAtReportIfErrors: Boolean=true): IErrorReporter {
+
+
+    val errors = mutableListOf<String>()
+    val warnings = mutableListOf<String>()
+
+    override fun err(msg: String, position: Position) {
+        errors.add("${position.toClickableStr()} $msg")
+    }
+
+    override fun warn(msg: String, position: Position) {
+        warnings.add("${position.toClickableStr()} $msg")
+    }
+
+    override fun noErrors(): Boolean  = errors.isEmpty()
+
+    override fun report() {
+        warnings.forEach { println("UNITTEST COMPILATION REPORT: WARNING: $it") }
+        errors.forEach { println("UNITTEST COMPILATION REPORT: ERROR: $it") }
+        if(throwExceptionAtReportIfErrors)
+            finalizeNumErrors(errors.size, warnings.size)
+        errors.clear()
+        warnings.clear()
+    }
+}

codeOptimizers/build.gradle

@@ -0,0 +1,54 @@
+
+plugins {
+    id 'java'
+    id 'application'
+    id "org.jetbrains.kotlin.jvm"
+}
+
+java {
+    toolchain {
+        languageVersion = JavaLanguageVersion.of(javaVersion)
+    }
+}
+
+dependencies {
+    implementation project(':compilerInterfaces')
+    implementation project(':compilerAst')
+    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8"
+    // implementation "org.jetbrains.kotlin:kotlin-reflect"
+
+    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'
+
+}
+
+sourceSets {
+    main {
+        java {
+            srcDirs = ["${project.projectDir}/src"]
+        }
+        resources {
+            srcDirs = ["${project.projectDir}/res"]
+        }
+    }
+    test {
+        java {
+            srcDirs = ["${project.projectDir}/test"]
+        }
+    }
+}
+
+test {
+    // Enable JUnit 5 (Gradle 4.6+).
+    useJUnitPlatform()
+
+    // Always run tests, even when nothing changed.
+    dependsOn 'cleanTest'
+
+    // Show test results.
+    testLogging {
+        events "skipped", "failed"
+    }
+}

codeOptimizers/codeOptimizers.iml

@@ -0,0 +1,18 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<module type="JAVA_MODULE" version="4">
+  <component name="NewModuleRootManager" inherit-compiler-output="true">
+    <exclude-output />
+    <content url="file://$MODULE_DIR$">
+      <sourceFolder url="file://$MODULE_DIR$/src" isTestSource="false" />
+      <sourceFolder url="file://$MODULE_DIR$/test" isTestSource="true" />
+      <excludeFolder url="file://$MODULE_DIR$/build" />
+    </content>
+    <orderEntry type="jdk" jdkName="openjdk-11" jdkType="JavaSDK" />
+    <orderEntry type="sourceFolder" forTests="false" />
+    <orderEntry type="library" name="KotlinJavaRuntime" level="project" />
+    <orderEntry type="module" module-name="compilerInterfaces" />
+    <orderEntry type="module" module-name="compilerAst" />
+    <orderEntry type="library" scope="TEST" name="hamcrest" level="project" />
+    <orderEntry type="library" name="junit.jupiter" level="project" />
+  </component>
+</module>

codeOptimizers/src/prog8/optimizer/BinExprSplitter.kt

@@ -1,21 +1,24 @@
 package prog8.optimizer
 
-import prog8.ast.INameScope
+import prog8.ast.IStatementContainer
 import prog8.ast.Node
 import prog8.ast.Program
+import prog8.ast.base.DataType
 import prog8.ast.expressions.BinaryExpression
 import prog8.ast.expressions.augmentAssignmentOperators
 import prog8.ast.statements.AssignTarget
 import prog8.ast.statements.Assignment
 import prog8.ast.walk.AstWalker
 import prog8.ast.walk.IAstModification
-import prog8.compiler.target.ICompilationTarget
+import prog8.compilerinterface.CompilationOptions
+import prog8.compilerinterface.ICompilationTarget
+import prog8.compilerinterface.isInRegularRAMof
 
 
-internal class BinExprSplitter(private val program: Program, private val compTarget: ICompilationTarget) : AstWalker() {
+class BinExprSplitter(private val program: Program, private val options: CompilationOptions, private val compTarget: ICompilationTarget) : AstWalker() {
 
 //    override fun after(decl: VarDecl, parent: Node): Iterable<IAstModification> {
-// TODO somehow if we do this, the resulting code for some programs (cube3d.p8) gets hundreds of bytes larger...:
+// TODO somehow if we do this, the resulting code for some programs (cube3d.p8) gets hundreds of bytes larger...: [ IS THIS STILL TRUE AFTER ALL CHANGES? ]
 //        if(decl.type==VarDeclType.VAR ) {
 //            val binExpr = decl.value as? BinaryExpression
 //            if (binExpr != null && binExpr.operator in augmentAssignmentOperators) {
@@ -37,6 +40,11 @@ internal class BinExprSplitter(private val program: Program, private val compTar
 
         val binExpr = assignment.value as? BinaryExpression
         if (binExpr != null) {
+
+            if(binExpr.inferType(program).istype(DataType.FLOAT) && !options.optimizeFloatExpressions)
+                return noModifications
+
+
 /*
 
 Reduce the complexity of a (binary) expression that has to be evaluated on the eval stack,
@@ -54,7 +62,7 @@ X =      BinExpr                                    X   =   LeftExpr
 
 
  */
-            if(binExpr.operator in augmentAssignmentOperators && isSimpleTarget(assignment.target, program)) {
+            if(binExpr.operator in augmentAssignmentOperators && isSimpleTarget(assignment.target)) {
                 if(assignment.target isSameAs binExpr.left || assignment.target isSameAs binExpr.right)
                     return noModifications
 
@@ -64,7 +72,7 @@ X =      BinExpr                                    X   =   LeftExpr
                     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 INameScope)
+                        IAstModification.InsertBefore(assignment, firstAssign, assignment.parent as IStatementContainer)
                     )
                 }
             }
@@ -77,9 +85,9 @@ X =      BinExpr                                    X   =   LeftExpr
         return noModifications
     }
 
-    private fun isSimpleTarget(target: AssignTarget, program: Program) =
+    private fun isSimpleTarget(target: AssignTarget) =
             if (target.identifier!=null || target.memoryAddress!=null)
-                compTarget.isInRegularRAM(target, program)
+                target.isInRegularRAMof(compTarget.machine)
             else
                 false
 

codeOptimizers/src/prog8/optimizer/ConstantFoldingOptimizer.kt

@@ -9,11 +9,10 @@ import prog8.ast.statements.ForLoop
 import prog8.ast.statements.VarDecl
 import prog8.ast.walk.AstWalker
 import prog8.ast.walk.IAstModification
-import prog8.compiler.target.ICompilationTarget
 import kotlin.math.pow
 
 
-internal class ConstantFoldingOptimizer(private val program: Program, private val compTarget: ICompilationTarget) : AstWalker() {
+class ConstantFoldingOptimizer(private val program: Program) : AstWalker() {
 
     override fun before(memread: DirectMemoryRead, parent: Node): Iterable<IAstModification> {
         // @( &thing )  -->  thing
@@ -106,7 +105,7 @@ internal class ConstantFoldingOptimizer(private val program: Program, private va
             // 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).typeOrElse(DataType.UNDEFINED)
+            val leftDt = leftconst.inferType(program).getOr(DataType.UNDEFINED)
             when (leftconst.number.toDouble()) {
                 0.0 -> {
                     val value = NumericLiteralValue(leftDt, 0, expr.position)
@@ -121,11 +120,11 @@ internal class ConstantFoldingOptimizer(private val program: Program, private va
                         val value = NumericLiteralValue(leftDt, 2.0.pow(rightconst.number.toDouble()), expr.position)
                         modifications += IAstModification.ReplaceNode(expr, value, parent)
                     } else {
-                        val rightDt = expr.right.inferType(program).typeOrElse(DataType.UNDEFINED)
+                        val rightDt = expr.right.inferType(program).getOr(DataType.UNDEFINED)
                         if(leftDt in IntegerDatatypes && rightDt in IntegerDatatypes) {
                             val targetDt =
                                 when (parent) {
-                                    is Assignment -> parent.target.inferType(program).typeOrElse(DataType.UNDEFINED)
+                                    is Assignment -> parent.target.inferType(program).getOr(DataType.UNDEFINED)
                                     is VarDecl -> parent.datatype
                                     else -> leftDt
                                 }
@@ -138,7 +137,7 @@ internal class ConstantFoldingOptimizer(private val program: Program, private va
             }
         }
 
-        if(expr.inferType(program).istype(DataType.FLOAT)) {
+        if(expr.inferType(program) istype DataType.FLOAT) {
             val subExpr: BinaryExpression? = when {
                 leftconst != null -> expr.right as? BinaryExpression
                 rightconst != null -> expr.left as? BinaryExpression
@@ -187,7 +186,7 @@ internal class ConstantFoldingOptimizer(private val program: Program, private va
         } else {
             val arrayDt = array.guessDatatype(program)
             if (arrayDt.isKnown) {
-                val newArray = array.cast(arrayDt.typeOrElse(DataType.UNDEFINED))
+                val newArray = array.cast(arrayDt.getOr(DataType.UNDEFINED))
                 if (newArray != null && newArray != array)
                     return listOf(IAstModification.ReplaceNode(array, newArray, parent))
             }
@@ -223,7 +222,7 @@ internal class ConstantFoldingOptimizer(private val program: Program, private va
                     range.step
                 }
 
-            return RangeExpr(fromCast.valueOrZero(), toCast.valueOrZero(), newStep, compTarget, range.position)
+            return RangeExpr(fromCast.valueOrZero(), toCast.valueOrZero(), newStep, range.position)
         }
 
         // adjust the datatype of a range expression in for loops to the loop variable.
@@ -278,7 +277,7 @@ internal class ConstantFoldingOptimizer(private val program: Program, private va
         val numval = decl.value as? NumericLiteralValue
         if(decl.type== VarDeclType.CONST && numval!=null) {
             val valueDt = numval.inferType(program)
-            if(!valueDt.istype(decl.datatype)) {
+            if(valueDt isnot decl.datatype) {
                 val cast = numval.cast(decl.datatype)
                 if(cast.isValid)
                     return listOf(IAstModification.ReplaceNode(numval, cast.valueOrZero(), decl))

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.*
@@ -8,17 +7,24 @@ 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.target.ICompilationTarget
+import prog8.compilerinterface.ICompilationTarget
+import prog8.compilerinterface.IErrorReporter
+import prog8.compilerinterface.size
+import prog8.compilerinterface.toConstantIntegerRange
 
 // Fix up the literal value's type to match that of the vardecl
-internal class VarConstantValueTypeAdjuster(private val program: Program, private val errors: IErrorReporter) : AstWalker() {
+//   (also check range literal operands types before they get expanded into arrays for instance)
+class VarConstantValueTypeAdjuster(private val program: Program, private val errors: IErrorReporter) : AstWalker() {
 
     override fun after(decl: VarDecl, parent: Node): Iterable<IAstModification> {
+
+        if(decl.parent is AnonymousScope)
+            throw FatalAstException("vardecl may no longer occur in anonymousscope")
+
         try {
             val declConstValue = decl.value?.constValue(program)
             if(declConstValue!=null && (decl.type==VarDeclType.VAR || decl.type==VarDeclType.CONST)
-                && !declConstValue.inferType(program).istype(decl.datatype)) {
+                && 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)
@@ -28,28 +34,35 @@ internal class VarConstantValueTypeAdjuster(private val program: Program, privat
             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()
+
+        if(from==null) {
+            if(!range.from.inferType(program).isInteger)
+                errors.err("range expression from value must be integer", range.from.position)
+        } else if(from-from.toInt()>0) {
+            errors.err("range expression from value must be integer", range.from.position)
         }
+
+        if(to==null) {
+            if(!range.to.inferType(program).isInteger)
+                errors.err("range expression to value must be integer", range.to.position)
+        } else if(to-to.toInt()>0) {
+            errors.err("range expression to value must be integer", range.to.position)
+        }
+
+        if(step==null) {
+            if(!range.step.inferType(program).isInteger)
+                errors.err("range expression step value must be integer", range.step.position)
+        } else if(step-step.toInt()>0) {
+            errors.err("range expression step value must be integer", range.step.position)
+        }
+
         return noModifications
     }
 }
@@ -124,7 +137,6 @@ internal class ConstantIdentifierReplacer(private val program: Program, private
                     }
                 }
                 DataType.ARRAY_UB, DataType.ARRAY_B, DataType.ARRAY_UW, DataType.ARRAY_W -> {
-                    val numericLv = decl.value as? NumericLiteralValue
                     val rangeExpr = decl.value as? RangeExpr
                     if(rangeExpr!=null) {
                         // convert the initializer range expression to an actual array
@@ -133,7 +145,7 @@ internal class ConstantIdentifierReplacer(private val program: Program, private
                             errors.err("range expression size doesn't match declared array size", decl.value?.position!!)
                         val constRange = rangeExpr.toConstantIntegerRange()
                         if(constRange!=null) {
-                            val eltType = rangeExpr.inferType(program).typeOrElse(DataType.UBYTE)
+                            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(),
@@ -146,6 +158,7 @@ internal class ConstantIdentifierReplacer(private val program: Program, private
                             return listOf(IAstModification.ReplaceNode(decl.value!!, newValue, decl))
                         }
                     }
+                    val numericLv = decl.value as? NumericLiteralValue
                     if(numericLv!=null && numericLv.type== DataType.FLOAT)
                         errors.err("arraysize requires only integers here", numericLv.position)
                     val size = decl.arraysize?.constIndex() ?: return noModifications
@@ -178,14 +191,12 @@ internal class ConstantIdentifierReplacer(private val program: Program, private
                     }
                 }
                 DataType.ARRAY_F -> {
-                    val size = decl.arraysize?.constIndex() ?: return noModifications
-                    val litval = decl.value as? NumericLiteralValue
                     val rangeExpr = decl.value as? RangeExpr
                     if(rangeExpr!=null) {
                         // convert the initializer range expression to an actual array of floats
                         val declArraySize = decl.arraysize?.constIndex()
                         if(declArraySize!=null && declArraySize!=rangeExpr.size())
-                            errors.err("range expression size doesn't match declared array size", decl.value?.position!!)
+                            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),
@@ -194,15 +205,18 @@ internal class ConstantIdentifierReplacer(private val program: Program, private
                             return listOf(IAstModification.ReplaceNode(decl.value!!, newValue, decl))
                         }
                     }
-                    if(rangeExpr==null && litval!=null) {
+
+                    val numericLv = decl.value as? NumericLiteralValue
+                    val size = decl.arraysize?.constIndex() ?: return noModifications
+                    if(rangeExpr==null && numericLv!=null) {
                         // arraysize initializer is a single int, and we know the size.
-                        val fillvalue = litval.number.toDouble()
+                        val fillvalue = numericLv.number.toDouble()
                         if (fillvalue < compTarget.machine.FLOAT_MAX_NEGATIVE || fillvalue > compTarget.machine.FLOAT_MAX_POSITIVE)
-                            errors.err("float value overflow", litval.position)
+                            errors.err("float value overflow", numericLv.position)
                         else {
                             // create the array itself, filled with the fillvalue.
-                            val array = Array(size) {fillvalue}.map { NumericLiteralValue(DataType.FLOAT, it, litval.position) }.toTypedArray<Expression>()
-                            val refValue = ArrayLiteralValue(InferredTypes.InferredType.known(DataType.ARRAY_F), array, position = litval.position)
+                            val array = Array(size) {fillvalue}.map { NumericLiteralValue(DataType.FLOAT, it, numericLv.position) }.toTypedArray<Expression>()
+                            val refValue = ArrayLiteralValue(InferredTypes.InferredType.known(DataType.ARRAY_F), array, position = numericLv.position)
                             return listOf(IAstModification.ReplaceNode(decl.value!!, refValue, decl))
                         }
                     }

codeOptimizers/src/prog8/optimizer/ExpressionSimplifier.kt

@@ -15,14 +15,25 @@ 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
 
+*(&X)  =>  X
+X % 1  => 0
+X / 1  =>  X
+X ^ -1  =>  ~x
+X >= 1  =>  X > 0
+X <  1  =>  X <= 0
+X + С1 == C2  =>  X == C2 - C1
+((X + C1) + C2)  =>  (X + (C1 + C2))
+((X + C1) + (Y + C2))  =>  ((X + Y) + (C1 + C2))
+
+
  */
 
 
-internal class ExpressionSimplifier(private val program: Program) : AstWalker() {
+class ExpressionSimplifier(private val program: Program) : AstWalker() {
     private val powersOfTwo = (1..16).map { (2.0).pow(it) }.toSet()
     private val negativePowersOfTwo = powersOfTwo.map { -it }.toSet()
 
@@ -45,7 +56,7 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
                 mods += IAstModification.ReplaceNode(typecast.expression, subTypecast.expression, typecast)
             }
         } else {
-            if (typecast.expression.inferType(program).istype(typecast.type)) {
+            if (typecast.expression.inferType(program) istype typecast.type) {
                 // remove duplicate cast
                 mods += IAstModification.ReplaceNode(typecast, typecast.expression, parent)
             }
@@ -134,8 +145,8 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
             ))
         }
 
-        val leftDt = leftIDt.typeOrElse(DataType.UNDEFINED)
-        val rightDt = rightIDt.typeOrElse(DataType.UNDEFINED)
+        val leftDt = leftIDt.getOr(DataType.UNDEFINED)
+        val rightDt = rightIDt.getOr(DataType.UNDEFINED)
 
         if (expr.operator == "+" || expr.operator == "-"
                 && leftVal == null && rightVal == null
@@ -289,13 +300,13 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
             val arg = functionCall.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 casted to word
+                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))
                 }
             } else {
                 val argDt = arg.inferType(program)
-                if (argDt.istype(DataType.BYTE) || argDt.istype(DataType.UBYTE)) {
+                if (argDt istype DataType.BYTE || argDt istype DataType.UBYTE) {
                     // useless lsb() of byte value
                     return listOf(IAstModification.ReplaceNode(functionCall, arg, parent))
                 }
@@ -305,20 +316,20 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
             val arg = functionCall.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 casted to word, replace with 0
+                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.typeOrElse(DataType.UBYTE), 0, arg.expression.position),
+                            NumericLiteralValue(valueDt.getOr(DataType.UBYTE), 0, arg.expression.position),
                             parent))
                 }
             } else {
                 val argDt = arg.inferType(program)
-                if (argDt.istype(DataType.BYTE) || argDt.istype(DataType.UBYTE)) {
+                if (argDt istype DataType.BYTE || argDt istype DataType.UBYTE) {
                     // useless msb() of byte value, replace with 0
                     return listOf(IAstModification.ReplaceNode(
                             functionCall,
-                            NumericLiteralValue(argDt.typeOrElse(DataType.UBYTE), 0, arg.position),
+                            NumericLiteralValue(argDt.getOr(DataType.UBYTE), 0, arg.position),
                             parent))
                 }
             }
@@ -489,7 +500,7 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
                     val idt = expr.inferType(program)
                     if(!idt.isKnown)
                         throw FatalAstException("unknown dt")
-                    return NumericLiteralValue(idt.typeOrElse(DataType.UNDEFINED), 0, expr.position)
+                    return NumericLiteralValue(idt.getOr(DataType.UNDEFINED), 0, expr.position)
                 } else if (cv in powersOfTwo) {
                     expr.operator = "&"
                     expr.right = NumericLiteralValue.optimalInteger(cv!!.toInt()-1, expr.position)
@@ -513,7 +524,7 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
             val leftIDt = expr.left.inferType(program)
             if (!leftIDt.isKnown)
                 return null
-            val leftDt = leftIDt.typeOrElse(DataType.UNDEFINED)
+            val leftDt = leftIDt.getOr(DataType.UNDEFINED)
             when (cv) {
                 -1.0 -> {
                     //  '/' -> -left
@@ -590,14 +601,14 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
                     return expr2.left
                 }
                 in powersOfTwo -> {
-                    if (leftValue.inferType(program).isInteger()) {
+                    if (leftValue.inferType(program).isInteger) {
                         // times a power of two => shift left
                         val numshifts = log2(cv).toInt()
                         return BinaryExpression(expr2.left, "<<", NumericLiteralValue.optimalInteger(numshifts, expr.position), expr.position)
                     }
                 }
                 in negativePowersOfTwo -> {
-                    if (leftValue.inferType(program).isInteger()) {
+                    if (leftValue.inferType(program).isInteger) {
                         // times a negative power of two => negate, then shift left
                         val numshifts = log2(-cv).toInt()
                         return BinaryExpression(PrefixExpression("-", expr2.left, expr.position), "<<", NumericLiteralValue.optimalInteger(numshifts, expr.position), expr.position)
@@ -621,7 +632,7 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
         val targetIDt = expr.left.inferType(program)
         if(!targetIDt.isKnown)
             throw FatalAstException("unknown dt")
-        when (val targetDt = targetIDt.typeOrElse(DataType.UNDEFINED)) {
+        when (val targetDt = targetIDt.getOr(DataType.UNDEFINED)) {
             DataType.UBYTE, DataType.BYTE -> {
                 if (amount >= 8) {
                     return NumericLiteralValue(targetDt, 0, expr.position)
@@ -656,7 +667,7 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
         val idt = expr.left.inferType(program)
         if(!idt.isKnown)
             throw FatalAstException("unknown dt")
-        when (idt.typeOrElse(DataType.UNDEFINED)) {
+        when (idt.getOr(DataType.UNDEFINED)) {
             DataType.UBYTE -> {
                 if (amount >= 8) {
                     return NumericLiteralValue.optimalInteger(0, expr.position)

codeOptimizers/src/prog8/optimizer/Extensions.kt

@@ -2,11 +2,12 @@ package prog8.optimizer
 
 import prog8.ast.IBuiltinFunctions
 import prog8.ast.Program
-import prog8.compiler.IErrorReporter
-import prog8.compiler.target.ICompilationTarget
+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()) {
@@ -21,7 +22,7 @@ internal fun Program.constantFold(errors: IErrorReporter, compTarget: ICompilati
             if(errors.noErrors()) {
                 valuetypefixer.applyModifications()
 
-                val optimizer = ConstantFoldingOptimizer(this, compTarget)
+                val optimizer = ConstantFoldingOptimizer(this)
                 optimizer.visit(this)
                 while (errors.noErrors() && optimizer.applyModifications() > 0) {
                     optimizer.visit(this)
@@ -40,9 +41,10 @@ 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 +54,14 @@ internal fun Program.optimizeStatements(errors: IErrorReporter,
     return optimizationCount
 }
 
-internal fun Program.simplifyExpressions() : Int {
+fun Program.simplifyExpressions() : Int {
     val opti = ExpressionSimplifier(this)
     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()
 }

codeOptimizers/src/prog8/optimizer/StatementOptimizer.kt

@@ -1,7 +1,7 @@
 package prog8.optimizer
 
 import prog8.ast.IBuiltinFunctions
-import prog8.ast.INameScope
+import prog8.ast.IStatementContainer
 import prog8.ast.Node
 import prog8.ast.Program
 import prog8.ast.base.*
@@ -10,19 +10,21 @@ 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.target.ICompilationTarget
+import prog8.compilerinterface.ICompilationTarget
+import prog8.compilerinterface.IErrorReporter
+import prog8.compilerinterface.size
 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>>()
+    private val subsThatNeedReturnVariable = mutableSetOf<Triple<IStatementContainer, DataType, Position>>()
 
 
     override fun after(subroutine: Subroutine, parent: Node): Iterable<IAstModification> {
@@ -39,12 +41,46 @@ internal class StatementOptimizer(private val program: Program,
         return noModifications
     }
 
+    override fun before(functionCall: FunctionCall, 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)
+        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)
+                        AddressOf(scoped, orig.position)
+                    }
+                    is DirectMemoryRead -> {
+                        when(val expr = orig.addressExpression) {
+                            is NumericLiteralValue -> DirectMemoryRead(expr.copy(), orig.position)
+                            else -> return noModifications
+                        }
+                    }
+                    is IdentifierReference -> scopePrefix(orig, subroutine)
+                    is NumericLiteralValue -> orig.copy()
+                    is StringLiteralValue -> orig.copy()
+                    else -> return noModifications
+                }
+                return listOf(IAstModification.ReplaceNode(functionCall, 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) {
             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))
             }
         }
 
@@ -82,7 +118,7 @@ internal class StatementOptimizer(private val program: Program,
                             functionCallStatement.void, pos
                         )
                         return listOf(
-                            IAstModification.InsertBefore(functionCallStatement, chrout1, parent as INameScope),
+                            IAstModification.InsertBefore(functionCallStatement, chrout1, parent as IStatementContainer),
                             IAstModification.ReplaceNode(functionCallStatement, chrout2, parent)
                         )
                     }
@@ -95,33 +131,33 @@ 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))
         }
 
         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 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> {
         // remove empty if statements
-        if(ifStatement.truepart.containsNoCodeNorVars() && ifStatement.elsepart.containsNoCodeNorVars())
-            return listOf(IAstModification.Remove(ifStatement, ifStatement.definingScope()))
+        if(ifStatement.truepart.isEmpty() && ifStatement.elsepart.isEmpty())
+            return listOf(IAstModification.Remove(ifStatement, parent as IStatementContainer))
 
         // empty true part? switch with the else part
-        if(ifStatement.truepart.containsNoCodeNorVars() && ifStatement.elsepart.containsCodeOrVars()) {
+        if(ifStatement.truepart.isEmpty() && ifStatement.elsepart.isNotEmpty()) {
             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)
@@ -149,20 +185,20 @@ 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
         if(range!=null) {
-            if(range.size()==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)
@@ -233,7 +269,7 @@ 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
@@ -242,14 +278,14 @@ 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)
@@ -261,10 +297,10 @@ internal class StatementOptimizer(private val program: Program,
 
     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 scope = jump.parent as IStatementContainer
         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()))
+            return listOf(IAstModification.Remove(jump, scope))
 
         return noModifications
     }
@@ -297,7 +333,7 @@ internal class StatementOptimizer(private val program: Program,
                                 )
                                 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
                                 val expr2 = BinaryExpression(binExpr.left, binExpr.operator, rExpr.left, binExpr.position)
@@ -308,7 +344,7 @@ internal class StatementOptimizer(private val program: Program,
                                 )
                                 return listOf(
                                         IAstModification.ReplaceNode(binExpr, expr2, binExpr.parent),
-                                        IAstModification.InsertAfter(assignment, subConstant, assignment.definingScope()))
+                                        IAstModification.InsertAfter(assignment, subConstant, parent as IStatementContainer))
                             }
                         }
                     }
@@ -330,7 +366,7 @@ 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)
@@ -338,7 +374,7 @@ internal class StatementOptimizer(private val program: Program,
             throw FatalAstException("can't infer type of assignment target")
 
         // optimize binary expressions a bit
-        val targetDt = targetIDt.typeOrElse(DataType.UNDEFINED)
+        val targetDt = targetIDt.getOr(DataType.UNDEFINED)
         val bexpr=assignment.value as? BinaryExpression
         if(bexpr!=null) {
             val rightCv = bexpr.right.constValue(program)?.number?.toDouble()
@@ -350,7 +386,7 @@ internal class StatementOptimizer(private val program: Program,
                 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)
@@ -364,7 +400,7 @@ internal class StatementOptimizer(private val program: Program,
                     }
                     "-" -> {
                         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)
@@ -376,18 +412,18 @@ 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))
                     }
                 }
 
@@ -399,7 +435,7 @@ internal class StatementOptimizer(private val program: Program,
 
     override fun after(returnStmt: Return, parent: Node): Iterable<IAstModification> {
         fun returnViaIntermediaryVar(value: Expression): Iterable<IAstModification>? {
-            val subr = returnStmt.definingSubroutine()!!
+            val subr = returnStmt.definingSubroutine!!
             val returnDt = subr.returntypes.single()
             if (returnDt in IntegerDatatypes) {
                 // first assign to intermediary variable, then return that
@@ -410,7 +446,7 @@ internal class StatementOptimizer(private val program: Program,
                 val assign = Assignment(tgt, value, returnStmt.position)
                 val returnReplacement = Return(returnValueIntermediary2, returnStmt.position)
                 return listOf(
-                    IAstModification.InsertBefore(returnStmt, assign, parent as INameScope),
+                    IAstModification.InsertBefore(returnStmt, assign, parent as IStatementContainer),
                     IAstModification.ReplaceNode(returnStmt, returnReplacement, parent)
                 )
             }
@@ -434,7 +470,7 @@ internal class StatementOptimizer(private val program: Program,
         return super.after(returnStmt, parent)
     }
 
-    private fun hasBreak(scope: INameScope): Boolean {
+    private fun hasBreak(scope: IStatementContainer): Boolean {
 
         class Searcher: IAstVisitor
         {

codeOptimizers/src/prog8/optimizer/UnusedCodeRemover.kt

@@ -9,46 +9,49 @@ import prog8.ast.expressions.TypecastExpression
 import prog8.ast.statements.*
 import prog8.ast.walk.AstWalker
 import prog8.ast.walk.IAstModification
-import prog8.compiler.IErrorReporter
-import prog8.compiler.target.ICompilationTarget
+import prog8.compilerinterface.CallGraph
+import prog8.compilerinterface.ICompilationTarget
+import prog8.compilerinterface.IErrorReporter
+import prog8.compilerinterface.isInRegularRAMof
 
 
-internal class UnusedCodeRemover(private val program: Program,
-                                 private val errors: IErrorReporter,
-                                 private val compTarget: ICompilationTarget): AstWalker() {
+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.isLibraryModule && (module.containsNoCodeNorVars() || callgraph.unused(module)))
-            listOf(IAstModification.Remove(module, module.definingScope()))
+        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, parent as INameScope)
+        reportUnreachable(breakStmt, parent as IStatementContainer)
         return emptyList()
     }
 
     override fun before(jump: Jump, parent: Node): Iterable<IAstModification> {
-        reportUnreachable(jump, parent as INameScope)
+        reportUnreachable(jump, parent as IStatementContainer)
         return emptyList()
     }
 
     override fun before(returnStmt: Return, parent: Node): Iterable<IAstModification> {
-        reportUnreachable(returnStmt, parent as INameScope)
+        reportUnreachable(returnStmt, parent as IStatementContainer)
         return emptyList()
     }
 
     override fun before(functionCallStatement: FunctionCallStatement, parent: Node): Iterable<IAstModification> {
         if(functionCallStatement.target.nameInSource.last() == "exit")
-            reportUnreachable(functionCallStatement, parent as INameScope)
+            reportUnreachable(functionCallStatement, parent as IStatementContainer)
         return emptyList()
     }
 
-    private fun reportUnreachable(stmt: Statement, parent: INameScope) {
-        when(val next = parent.nextSibling(stmt)) {
+    private fun reportUnreachable(stmt: Statement, parent: IStatementContainer) {
+        when(val next = stmt.nextSibling()) {
             null, is Label, is Directive, is VarDecl, is InlineAssembly, is Subroutine -> {}
             else -> errors.warn("unreachable code", next.position)
         }
@@ -61,14 +64,14 @@ internal class UnusedCodeRemover(private val program: Program,
 
     override fun after(block: Block, parent: Node): Iterable<IAstModification> {
         if("force_output" !in block.options()) {
-            if (block.containsNoCodeNorVars()) {
+            if (block.containsNoCodeNorVars) {
                 if(block.name != internedStringsModuleName)
                     errors.warn("removing unused block '${block.name}'", block.position)
-                return listOf(IAstModification.Remove(block, parent as INameScope))
+                return listOf(IAstModification.Remove(block, parent as IStatementContainer))
             }
             if(callgraph.unused(block)) {
                 errors.warn("removing unused block '${block.name}'", block.position)
-                return listOf(IAstModification.Remove(block, parent as INameScope))
+                return listOf(IAstModification.Remove(block, parent as IStatementContainer))
             }
         }
 
@@ -77,22 +80,22 @@ internal class UnusedCodeRemover(private val program: Program,
     }
 
     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) {
+        val forceOutput = "force_output" in subroutine.definingBlock.options()
+        if (subroutine !== program.entrypoint && !forceOutput && !subroutine.inline && !subroutine.isAsmSubroutine) {
             if(callgraph.unused(subroutine)) {
-                if(!subroutine.definingModule().isLibraryModule)
-                    errors.warn("removing unused subroutine '${subroutine.name}'", subroutine.position)
-                return listOf(IAstModification.Remove(subroutine, subroutine.definingScope()))
-            }
-            if(subroutine.containsNoCodeNorVars()) {
-                if(!subroutine.definingModule().isLibraryModule)
-                    errors.warn("removing empty subroutine '${subroutine.name}'", subroutine.position)
-                val removals = mutableListOf(IAstModification.Remove(subroutine, subroutine.definingScope()))
-                callgraph.calledBy[subroutine]?.let {
-                    for(node in it)
-                        removals.add(IAstModification.Remove(node, node.definingScope()))
+                if(subroutine.containsNoCodeNorVars) {
+                    if(!subroutine.definingModule.isLibrary)
+                        errors.warn("removing empty subroutine '${subroutine.name}'", subroutine.position)
+                    val removals = mutableListOf(IAstModification.Remove(subroutine, parent as IStatementContainer))
+                    callgraph.calledBy[subroutine]?.let {
+                        for(node in it)
+                            removals.add(IAstModification.Remove(node, node.parent as IStatementContainer))
+                    }
+                    return removals
                 }
-                return removals
+                if(!subroutine.definingModule.isLibrary)
+                    errors.warn("removing unused subroutine '${subroutine.name}'", subroutine.position)
+                return listOf(IAstModification.Remove(subroutine, parent as IStatementContainer))
             }
         }
 
@@ -102,11 +105,11 @@ internal class UnusedCodeRemover(private val program: Program,
 
     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.autogeneratedDontRemove && !decl.sharedWithAsm && !decl.definingBlock().isInLibrary) {
+            val forceOutput = "force_output" in decl.definingBlock.options()
+            if (!forceOutput && !decl.autogeneratedDontRemove && !decl.sharedWithAsm && !decl.definingBlock.isInLibrary) {
                 if (callgraph.unused(decl)) {
                     errors.warn("removing unused variable '${decl.name}'", decl.position)
-                    return listOf(IAstModification.Remove(decl, decl.definingScope()))
+                    return listOf(IAstModification.Remove(decl, parent as IStatementContainer))
                 }
             }
         }
@@ -122,7 +125,7 @@ internal class UnusedCodeRemover(private val program: Program,
             val assign1 = stmtPairs[0] as? Assignment
             val assign2 = stmtPairs[1] as? Assignment
             if (assign1 != null && assign2 != null && !assign2.isAugmentable) {
-                if (assign1.target.isSameAs(assign2.target, program) && compTarget.isInRegularRAM(assign1.target, program))  {
+                if (assign1.target.isSameAs(assign2.target, program) && assign1.target.isInRegularRAMof(compTarget.machine))  {
                     if(assign2.target.identifier==null || !assign2.value.referencesIdentifier(*(assign2.target.identifier!!.nameInSource.toTypedArray())))
                         // only remove the second assignment if its value is a simple expression!
                         when(assign2.value) {

codeOptimizers/test/readme.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.

compiler/build.gradle

@@ -2,31 +2,31 @@ plugins {
     id 'java'
     id 'application'
     id "org.jetbrains.kotlin.jvm"
-    id 'com.github.johnrengelman.shadow' version '7.0.0'
+    id 'com.github.johnrengelman.shadow' version '7.1.0'
 }
 
-targetCompatibility = 11
-sourceCompatibility = 11
-
-
-repositories {
-    mavenLocal()
-    mavenCentral()
-    maven { url "https://kotlin.bintray.com/kotlinx" }
+java {
+    toolchain {
+        languageVersion = JavaLanguageVersion.of(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.jetbrains.kotlin:kotlin-stdlib-jdk8"
     // implementation "org.jetbrains.kotlin:kotlin-reflect"
-    implementation 'org.jetbrains.kotlinx:kotlinx-cli:0.3.2'
+    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:5.3.2'
-    testImplementation 'org.hamcrest:hamcrest-junit:2.0.0.0'
-    testRuntimeOnly 'org.junit.jupiter:junit-jupiter-engine:5.3.2'
+    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'
 }
 
 configurations.all {
@@ -43,22 +43,6 @@ configurations {
 }
 
 
-compileKotlin {
-    kotlinOptions {
-        jvmTarget = "11"
-        useIR = true
-        // verbose = true
-        // freeCompilerArgs += "-XXLanguage:+NewInference"
-    }
-}
-
-compileTestKotlin {
-    kotlinOptions {
-        jvmTarget = "11"
-        useIR = true
-    }
-}
-
 sourceSets {
     main {
         java {
@@ -70,7 +54,8 @@ sourceSets {
     }
     test {
         java {
-            srcDirs = ["${project.projectDir}/test"]
+            srcDir "${project.projectDir}/test"
+            srcDir "${project(':compilerAst').projectDir}/test/helpers"
         }
     }
 }
@@ -82,11 +67,6 @@ application {
     applicationName = 'p8compile'
 }
 
-artifacts {
-    archives shadowJar
-}
-
-
 shadowJar {
     archiveBaseName = 'prog8compiler'
     archiveVersion = prog8version
@@ -106,3 +86,5 @@ test {
         events "skipped", "failed"
     }
 }
+
+build.finalizedBy installDist, installShadowDist

compiler/compiler.iml

@@ -16,9 +16,14 @@
     <orderEntry type="jdk" jdkName="openjdk-11" jdkType="JavaSDK" />
     <orderEntry type="sourceFolder" forTests="false" />
     <orderEntry type="library" name="KotlinJavaRuntime" level="project" />
-    <orderEntry type="library" name="unittest-libs" level="project" />
-    <orderEntry type="library" name="kotlinx-cli-jvm" 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" />
   </component>
 </module>

compiler/res/prog8lib/c64/floats.p8

@@ -4,7 +4,6 @@
 ;
 ; indent format: TABS, size=8
 
-%target c64
 %option enable_floats
 
 floats {
@@ -13,6 +12,7 @@ floats {
         const float  PI     = 3.141592653589793
         const float  TWOPI  = 6.283185307179586
 
+        ubyte[5] tempvar_swap_float     ; used for some swap() operations
 
 ; ---- C64 basic and kernal ROM float constants and functions ----
 

compiler/res/prog8lib/c64/graphics.p8

@@ -1,4 +1,3 @@
-%target c64
 %import textio
 
 ; bitmap pixel graphics module for the C64

compiler/res/prog8lib/c64/syslib.p8

@@ -5,8 +5,6 @@
 ;
 ; indent format: TABS, size=8
 
-%target c64
-
 c64 {
         &ubyte  TIME_HI         = $a0       ; software jiffy clock, hi byte
         &ubyte  TIME_MID        = $a1       ;  .. mid byte
@@ -502,11 +500,9 @@ sys {
         ; --- 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 {{
--           lda  c64.RASTER
-            beq  -
--           lda  c64.RASTER
-            bne  -
-            bit  c64.SCROLY
+-           bit  c64.SCROLY
+            bpl  -
+-           bit  c64.SCROLY
             bmi  -
             rts
         }}

compiler/res/prog8lib/c64/textio.p8

@@ -4,7 +4,6 @@
 ;
 ; indent format: TABS, size=8
 
-%target c64
 %import syslib
 %import conv
 

compiler/res/prog8lib/cx16/floats.p8

@@ -4,17 +4,17 @@
 ;
 ; indent format: TABS, size=8
 
-%target cx16
 %option enable_floats
 
 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
 
+        ubyte[5] tempvar_swap_float     ; used for some swap() operations
+
 
 ; ---- ROM float functions ----
 

compiler/res/prog8lib/cx16/gfx2.p8

@@ -1,5 +1,3 @@
-%target cx16
-
 ; Bitmap pixel graphics routines for the CommanderX16
 ; Custom routines to use the full-screen 640x480 and 320x240 screen modes.
 ; (These modes are not supported by the documented GRAPH_xxxx kernal routines)

compiler/res/prog8lib/cx16/graphics.p8

@@ -1,4 +1,3 @@
-%target cx16
 %import syslib
 %import textio
 

compiler/res/prog8lib/cx16/palette.p8

@@ -1,5 +1,3 @@
-%target cx16
-
 ; Manipulate the Commander X16's display color palette.
 ; Should you want to restore the default palette, you have to reinitialize the Vera yourself.
 
@@ -9,7 +7,7 @@ palette {
     ubyte c
 
     sub set_color(ubyte index, uword color) {
-        vera_palette_ptr = $fa00+index*2
+        vera_palette_ptr = $fa00+(index as uword * 2)
         cx16.vpoke(1, vera_palette_ptr, lsb(color))
         vera_palette_ptr++
         cx16.vpoke(1, vera_palette_ptr, msb(color))
@@ -70,11 +68,11 @@ palette {
         }
     }
 
-    inline sub set_all_black() {
+    sub set_all_black() {
         set_monochrome($000, $000)
     }
 
-    inline sub set_all_white() {
+    sub set_all_white() {
         set_monochrome($fff, $fff)
     }
 

compiler/res/prog8lib/cx16/syslib.p8

@@ -5,9 +5,6 @@
 ;
 ; indent format: TABS, size=8
 
-%target cx16
-
-
 c64 {
 
 ; ---- kernal routines, these are the same as on the Commodore-64 (hence the same block name) ----

compiler/res/prog8lib/cx16/textio.p8

@@ -4,7 +4,6 @@
 ;
 ; indent format: TABS, size=8
 
-%target cx16
 %import syslib
 %import conv
 

compiler/res/prog8lib/prog8_lib.p8

@@ -6,10 +6,12 @@ prog8_lib {
 	%asminclude "library:prog8_lib.asm"
 	%asminclude "library:prog8_funcs.asm"
 
+        ; TODO these retval variables are no longer used???
 	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)
+	; NOTE: these variables are checked in the StatementReorderer (in fun after(decl: VarDecl)), for these exact names!
 
 	asmsub pattern_match(str string @AY, str pattern @R0) clobbers(Y) -> ubyte @A {
 		%asm {{

compiler/res/version.txt

@@ -1 +1 @@
-7.0
+7.2

compiler/src/prog8/CompilerMain.kt

@@ -6,7 +6,6 @@ import prog8.compiler.CompilationResult
 import prog8.compiler.compileProgram
 import prog8.compiler.target.C64Target
 import prog8.compiler.target.Cx16Target
-import prog8.parser.ParsingFailedError
 import java.io.File
 import java.nio.file.FileSystems
 import java.nio.file.Path
@@ -16,55 +15,56 @@ import kotlin.system.exitProcess
 
 
 fun main(args: Array<String>) {
-    printSoftwareHeader("compiler")
-
-    compileMain(args)
-}
-
-internal fun printSoftwareHeader(what: String) {
     val buildVersion = object {}.javaClass.getResource("/version.txt").readText().trim()
-    println("\nProg8 $what v$buildVersion by Irmen de Jong (irmen@razorvine.net)")
+    println("\nProg8 compiler v$buildVersion by Irmen de Jong (irmen@razorvine.net)")
     println("This software is licensed under the GNU GPL 3.0, see https://www.gnu.org/licenses/gpl.html\n")
+
+    val succes = compileMain(args)
+    if(!succes)
+        exitProcess(1)
 }
 
 
 fun pathFrom(stringPath: String, vararg rest: String): Path  = FileSystems.getDefault().getPath(stringPath, *rest)
 
 
-private fun compileMain(args: Array<String>) {
+private fun compileMain(args: Array<String>): Boolean {
     val cli = ArgParser("prog8compiler", prefixStyle = ArgParser.OptionPrefixStyle.JVM)
-    val startEmulator by cli.option(ArgType.Boolean, fullName = "emu", description = "auto-start emulator after successful compilation")
+    val startEmulator1 by cli.option(ArgType.Boolean, fullName = "emu", description = "auto-start emulator after successful compilation")
+    val startEmulator2 by cli.option(ArgType.Boolean, fullName = "emu2", description = "auto-start alternative emulator after successful compilation")
     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 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 quietAssembler by cli.option(ArgType.Boolean, fullName = "quietasm", description = "don't print assembler output results")
     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 libDirs by cli.option(ArgType.String, fullName="libdirs", description = "list of extra paths to search in for imported modules").multiple().delimiter(File.pathSeparator)
+    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 {
         cli.parse(args)
     } catch (e: IllegalStateException) {
         System.err.println(e.message)
-        exitProcess(1)
+        return false
     }
 
     val outputPath = pathFrom(outputDir)
     if(!outputPath.toFile().isDirectory) {
         System.err.println("Output path doesn't exist")
-        exitProcess(1)
+        return false
     }
 
     val faultyOption = moduleFiles.firstOrNull { it.startsWith('-') }
     if(faultyOption!=null) {
         System.err.println("Unknown command line option given: $faultyOption")
-        exitProcess(1)
+        return false
     }
 
-    val libdirs = libDirs.toMutableList()
-    if(libdirs.firstOrNull()!=".")
-        libdirs.add(0, ".")
+    val srcdirs = sourceDirs.toMutableList()
+    if(srcdirs.firstOrNull()!=".")
+        srcdirs.add(0, ".")
 
     if(watchMode==true) {
         val watchservice = FileSystems.getDefault().newWatchService()
@@ -75,7 +75,10 @@ private fun compileMain(args: Array<String>) {
             val results = mutableListOf<CompilationResult>()
             for(filepathRaw in moduleFiles) {
                 val filepath = pathFrom(filepathRaw).normalize()
-                val compilationResult = compileProgram(filepath, dontOptimize!=true, dontWriteAssembly!=true, slowCodegenWarnings==true, compilationTarget, libdirs, outputPath)
+                val compilationResult = compileProgram(filepath,
+                    dontOptimize!=true, optimizeFloatExpressions==true,
+                    dontWriteAssembly!=true, slowCodegenWarnings==true, quietAssembler==true,
+                    compilationTarget, srcdirs, outputPath)
                 results.add(compilationResult)
             }
 
@@ -86,7 +89,7 @@ private fun compileMain(args: Array<String>) {
             for (importedFile in allImportedFiles) {
                 print("  ")
                 println(importedFile)
-                val watchDir = importedFile.parent ?: Path.of(".")
+                val watchDir = importedFile.parent ?: Path.of("")
                 watchDir.register(watchservice, StandardWatchEventKinds.ENTRY_MODIFY)
             }
             println("[${LocalDateTime.now().withNano(0)}]  Waiting for file changes.")
@@ -112,22 +115,31 @@ private fun compileMain(args: Array<String>) {
             val filepath = pathFrom(filepathRaw).normalize()
             val compilationResult: CompilationResult
             try {
-                compilationResult = compileProgram(filepath, dontOptimize!=true, dontWriteAssembly!=true, slowCodegenWarnings==true, compilationTarget, libdirs, outputPath)
+                compilationResult = compileProgram(filepath,
+                    dontOptimize!=true, optimizeFloatExpressions==true,
+                    dontWriteAssembly!=true, slowCodegenWarnings==true, quietAssembler==true,
+                    compilationTarget, srcdirs, outputPath)
                 if(!compilationResult.success)
-                    exitProcess(1)
-            } catch (x: ParsingFailedError) {
-                exitProcess(1)
+                    return false
             } catch (x: AstException) {
-                exitProcess(1)
+                return false
             }
 
-            if (startEmulator==true) {
-                if (compilationResult.programName.isEmpty())
+            if(startEmulator1==true || startEmulator2==true) {
+                if (compilationResult.programName.isEmpty()) {
                     println("\nCan't start emulator because no program was assembled.")
-                else {
-                    compilationResult.compTarget.machine.launchEmulator(compilationResult.programName)
+                    return true
                 }
             }
+
+            val programNameInPath = outputPath.resolve(compilationResult.programName)
+
+            if (startEmulator1==true)
+                compilationResult.compTarget.machine.launchEmulator(1, programNameInPath)
+            else if (startEmulator2==true)
+                compilationResult.compTarget.machine.launchEmulator(2, programNameInPath)
         }
     }
+
+    return true
 }

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

@@ -1,6 +1,7 @@
 package prog8.compiler
 
 import prog8.ast.IFunctionCall
+import prog8.ast.IStatementContainer
 import prog8.ast.Node
 import prog8.ast.Program
 import prog8.ast.base.*
@@ -9,27 +10,18 @@ import prog8.ast.statements.*
 import prog8.ast.walk.AstWalker
 import prog8.ast.walk.IAstModification
 import prog8.ast.walk.IAstVisitor
-import prog8.compiler.target.ICompilationTarget
+import prog8.compiler.astprocessing.isSubroutineParameter
+import prog8.compilerinterface.*
 
 
-internal class BeforeAsmGenerationAstChanger(val program: Program, val errors: IErrorReporter, private val compTarget: ICompilationTarget) : AstWalker() {
+internal class BeforeAsmGenerationAstChanger(val program: Program, private val options: CompilationOptions,
+                                             private val errors: IErrorReporter) : AstWalker() {
 
     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")
+
         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
     }
 
@@ -39,8 +31,12 @@ internal class BeforeAsmGenerationAstChanger(val program: Program, val errors: I
         // But it can only be done if the target variable IS NOT OCCURRING AS AN OPERAND ITSELF.
         if(!assignment.isAugmentable
                 && assignment.target.identifier != null
-                && compTarget.isInRegularRAM(assignment.target, program)) {
+                && assignment.target.isInRegularRAMof(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.toTypedArray())) {
@@ -51,14 +47,14 @@ internal class BeforeAsmGenerationAstChanger(val program: Program, val errors: I
                             // 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.InsertBefore(assignment, assignRight, parent as IStatementContainer),
                                     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.InsertBefore(assignment, assignLeft, parent as IStatementContainer),
                                 IAstModification.ReplaceNode(binExpr.left, assignment.target.toExpression(), binExpr))
                     }
                 }
@@ -73,33 +69,35 @@ internal class BeforeAsmGenerationAstChanger(val program: Program, val errors: I
     override fun before(subroutine: Subroutine, parent: Node): Iterable<IAstModification> {
         subroutineVariables.clear()
         addedIfConditionVars.clear()
+
+        if(!subroutine.isAsmSubroutine) {
+            // change 'str' parameters into 'uword' (just treat it as an address)
+            val stringParams = subroutine.parameters.filter { it.type==DataType.STR }
+            val parameterChanges = stringParams.map {
+                val uwordParam = SubroutineParameter(it.name, DataType.UWORD, it.position)
+                IAstModification.ReplaceNode(it, uwordParam, subroutine)
+            }
+
+            val stringParamNames = stringParams.map { it.name }.toSet()
+            val varsChanges  = subroutine.statements
+                .filterIsInstance<VarDecl>()
+                .filter { it.autogeneratedDontRemove && it.name in stringParamNames }
+                .map {
+                    val newvar = VarDecl(it.type, DataType.UWORD, it.zeropage, null, it.name, null, false, true, it.sharedWithAsm, it.position)
+                    IAstModification.ReplaceNode(it, newvar, subroutine)
+                }
+
+            return parameterChanges + varsChanges
+        }
         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")
+
         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
     }
 
@@ -119,17 +117,17 @@ internal class BeforeAsmGenerationAstChanger(val program: Program, val errors: I
         // 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
-                && subroutine.statements.isNotEmpty()
-                && subroutine.amountOfRtsInAsm() == 0
+        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)
+                && 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 outerScope = subroutine.definingScope
         val outerStatements = outerScope.statements
         val subroutineStmtIdx = outerStatements.indexOf(subroutine)
         if (subroutineStmtIdx > 0
@@ -145,8 +143,9 @@ internal class BeforeAsmGenerationAstChanger(val program: Program, val errors: I
     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).typeOrElse(DataType.UNDEFINED)
+        // 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) {
@@ -154,22 +153,23 @@ internal class BeforeAsmGenerationAstChanger(val program: Program, val errors: I
             }
         }
 
-
-        // 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(
+                val identifier = typecast.expression as? IdentifierReference
+                if(identifier!=null) {
+                    return if(identifier.isSubroutineParameter(program)) {
+                        listOf(IAstModification.ReplaceNode(
                             typecast,
-                            AddressOf(typecast.expression as IdentifierReference, typecast.position),
+                            typecast.expression,
                             parent
-                    ))
+                        ))
+                    } else {
+                        listOf(IAstModification.ReplaceNode(
+                            typecast,
+                            AddressOf(identifier, typecast.position),
+                            parent
+                        ))
+                    }
                 } else if(typecast.expression is IFunctionCall) {
                     return listOf(IAstModification.ReplaceNode(
                             typecast,
@@ -185,7 +185,15 @@ internal class BeforeAsmGenerationAstChanger(val program: Program, val errors: I
         return noModifications
     }
 
+    @Suppress("DuplicatedCode")
     override fun after(ifStatement: IfStatement, parent: Node): Iterable<IAstModification> {
+        val prefixExpr = ifStatement.condition as? PrefixExpression
+        if(prefixExpr!=null && prefixExpr.operator=="not") {
+            // if not x -> if x==0
+            val booleanExpr = BinaryExpression(prefixExpr.expression, "==", NumericLiteralValue.optimalInteger(0, ifStatement.condition.position), ifStatement.condition.position)
+            return listOf(IAstModification.ReplaceNode(ifStatement.condition, booleanExpr, ifStatement))
+        }
+
         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
@@ -196,52 +204,20 @@ internal class BeforeAsmGenerationAstChanger(val program: Program, val errors: I
         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")
+            throw InternalCompilerException("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)
-//        }
-//    }
-
+    @Suppress("DuplicatedCode")
     override fun after(untilLoop: UntilLoop, parent: Node): Iterable<IAstModification> {
+        val prefixExpr = untilLoop.condition as? PrefixExpression
+        if(prefixExpr!=null && prefixExpr.operator=="not") {
+            // until not x -> until x==0
+            val booleanExpr = BinaryExpression(prefixExpr.expression, "==", NumericLiteralValue.optimalInteger(0, untilLoop.condition.position), untilLoop.condition.position)
+            return listOf(IAstModification.ReplaceNode(untilLoop.condition, booleanExpr, untilLoop))
+        }
+
         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
@@ -251,7 +227,15 @@ internal class BeforeAsmGenerationAstChanger(val program: Program, val errors: I
         return noModifications
     }
 
+    @Suppress("DuplicatedCode")
     override fun after(whileLoop: WhileLoop, parent: Node): Iterable<IAstModification> {
+        val prefixExpr = whileLoop.condition as? PrefixExpression
+        if(prefixExpr!=null && prefixExpr.operator=="not") {
+            // while not x -> while x==0
+            val booleanExpr = BinaryExpression(prefixExpr.expression, "==", NumericLiteralValue.optimalInteger(0, whileLoop.condition.position), whileLoop.condition.position)
+            return listOf(IAstModification.ReplaceNode(whileLoop.condition, booleanExpr, whileLoop))
+        }
+
         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
@@ -266,8 +250,8 @@ internal class BeforeAsmGenerationAstChanger(val program: Program, val errors: I
             // 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).typeOrElse(DataType.UNDEFINED)
-            val dt2 = arg2.inferType(program).typeOrElse(DataType.UNDEFINED)
+            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
@@ -339,14 +323,14 @@ internal class BeforeAsmGenerationAstChanger(val program: Program, val errors: I
 
     private fun getAutoIndexerVarFor(expr: ArrayIndexedExpression): MutableList<IAstModification> {
         val modifications = mutableListOf<IAstModification>()
-        val statement = expr.containingStatement()
+        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"
+        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.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/Compiler.kt

@@ -1,8 +1,8 @@
 package prog8.compiler
 
-import prog8.ast.AstToSourceCode
+import com.github.michaelbull.result.*
+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
@@ -10,109 +10,100 @@ import prog8.ast.expressions.Expression
 import prog8.ast.expressions.NumericLiteralValue
 import prog8.ast.statements.Directive
 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.compiler.target.cpu6502.codegen.AsmGen
+import prog8.compilerinterface.*
 import prog8.optimizer.*
-import prog8.parser.ModuleImporter
-import prog8.parser.ParsingFailedError
-import prog8.parser.moduleName
-import java.io.File
-import java.io.InputStream
+import prog8.parser.ParseError
 import java.nio.file.Path
-import kotlin.system.exitProcess
+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>)
 
 
+// TODO refactor the gigantic list of parameters
 fun compileProgram(filepath: Path,
                    optimize: Boolean,
+                   optimizeFloatExpressions: Boolean,
                    writeAssembly: Boolean,
                    slowCodegenWarnings: Boolean,
+                   quietAssembler: Boolean,
                    compilationTarget: String,
-                   libdirs: List<String>,
-                   outputDir: Path): CompilationResult {
+                   sourceDirs: List<String>,
+                   outputDir: Path,
+                   errors: IErrorReporter = ErrorReporter()): CompilationResult {
     var programName = ""
-    lateinit var programAst: Program
+    lateinit var program: Program
     lateinit var importedFiles: List<Path>
-    val errors = ErrorReporter()
 
     val compTarget =
         when(compilationTarget) {
             C64Target.name -> C64Target
             Cx16Target.name -> Cx16Target
-            else -> {
-                System.err.println("invalid compilation target")
-                exitProcess(1)
-            }
+            else -> throw IllegalArgumentException("invalid compilation target")
         }
 
     try {
         val totalTime = measureTimeMillis {
             // import main module and everything it needs
-            val (ast, compilationOptions, imported) = parseImports(filepath, errors, compTarget, libdirs)
-            compilationOptions.slowCodegenWarnings = slowCodegenWarnings
-            compilationOptions.optimize = optimize
-            programAst = ast
+            val (programresult, compilationOptions, imported) = parseImports(filepath, errors, compTarget, sourceDirs)
+            with(compilationOptions) {
+                this.slowCodegenWarnings = slowCodegenWarnings
+                this.optimize = optimize
+                this.optimizeFloatExpressions = optimizeFloatExpressions
+            }
+            program = programresult
             importedFiles = imported
-            processAst(programAst, errors, compilationOptions)
+            processAst(program, errors, compilationOptions)
             if (compilationOptions.optimize)
-                optimizeAst(programAst, errors, BuiltinFunctionsFacade(BuiltinFunctions), compTarget, compilationOptions)
-            postprocessAst(programAst, errors, compilationOptions)
+                optimizeAst(
+                    program,
+                    compilationOptions,
+                    errors,
+                    BuiltinFunctionsFacade(BuiltinFunctions),
+                    compTarget
+                )
+            postprocessAst(program, errors, compilationOptions)
 
-            // printAst(programAst)
+//            println("*********** AST BEFORE ASSEMBLYGEN *************")
+//            printAst(program)
 
-            if(writeAssembly)
-                programName = writeAssembly(programAst, errors, outputDir, compilationOptions)
+            if (writeAssembly) {
+                val result = writeAssembly(program, errors, outputDir, quietAssembler, compilationOptions)
+                when (result) {
+                    is WriteAssemblyResult.Ok -> programName = result.filename
+                    is WriteAssemblyResult.Fail -> {
+                        System.err.println(result.error)
+                        return CompilationResult(false, program, programName, compTarget, importedFiles)
+                    }
+                }
+            }
         }
         System.out.flush()
         System.err.flush()
         println("\nTotal compilation+assemble time: ${totalTime / 1000.0} sec.")
-        return CompilationResult(true, programAst, programName, compTarget, importedFiles)
-
-    } catch (px: ParsingFailedError) {
+        return CompilationResult(true, program, programName, compTarget, importedFiles)
+    } catch (px: ParseError) {
         System.err.print("\u001b[91m")  // bright red
-        System.err.println(px.message)
+        System.err.println("${px.position.toClickableStr()} parse error: ${px.message}".trim())
+        System.err.print("\u001b[0m")  // reset
+    } 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("File not found: ${nsf.message}")
         System.err.print("\u001b[0m")  // reset
     } catch (ax: AstException) {
         System.err.print("\u001b[91m")  // bright red
@@ -132,7 +123,7 @@ fun compileProgram(filepath: Path,
         throw x
     }
 
-    val failedProgram = Program("failed", mutableListOf(), BuiltinFunctionsFacade(BuiltinFunctions), compTarget)
+    val failedProgram = Program("failed", BuiltinFunctionsFacade(BuiltinFunctions), compTarget, compTarget)
     return CompilationResult(false, failedProgram, programName, compTarget, emptyList())
 }
 
@@ -142,13 +133,13 @@ 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
@@ -166,43 +157,46 @@ private class BuiltinFunctionsFacade(functions: Map<String, FSignature>): IBuilt
         builtinFunctionReturnType(name, args, program)
 }
 
-private fun parseImports(filepath: Path,
-                         errors: IErrorReporter,
-                         compTarget: ICompilationTarget,
-                         libdirs: List<String>): Triple<Program, CompilationOptions, List<Path>> {
-    val compilationTargetName = compTarget.name
-    println("Compiler target: $compilationTargetName. Parsing...")
+fun parseImports(filepath: Path,
+                 errors: IErrorReporter,
+                 compTarget: ICompilationTarget,
+                 sourceDirs: List<String>): Triple<Program, CompilationOptions, List<Path>> {
+    println("Compiler target: ${compTarget.name}. Parsing...")
     val bf = BuiltinFunctionsFacade(BuiltinFunctions)
-    val programAst = Program(moduleName(filepath.fileName), mutableListOf(), bf, compTarget)
-    bf.program = programAst
+    val program = Program(filepath.nameWithoutExtension, bf, compTarget, compTarget)
+    bf.program = program
 
-    val importer = ModuleImporter(programAst, compTarget, compilationTargetName, libdirs)
-    importer.importModule(filepath)
+    val importer = ModuleImporter(program, compTarget.name, errors, sourceDirs)
+    val importedModuleResult = importer.importModule(filepath)
+    importedModuleResult.onFailure { throw it }
     errors.report()
 
-    val importedFiles = programAst.modules.filter { !it.source.startsWith("@embedded@") }.map { it.source }
-    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 importedFiles = program.modules.map { it.source }
+        .filter { it.isFromFilesystem }
+        .map { Path(it.origin) }
+    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, compilationTargetName))
+    for(lib in compTarget.machine.importLibs(compilerOptions, compTarget.name))
         importer.importLibraryModule(lib)
 
     // 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)
 }
 
-private fun determineCompilationOptions(program: Program, compTarget: ICompilationTarget): CompilationOptions {
-    val mainModule = program.mainModule
-    val outputType = (mainModule.statements.singleOrNull { it is Directive && it.directive == "%output" }
-            as? Directive)?.args?.single()?.name?.uppercase()
-    val launcherType = (mainModule.statements.singleOrNull { it is Directive && it.directive == "%launcher" }
-            as? Directive)?.args?.single()?.name?.uppercase()
-    val zpoption: String? = (mainModule.statements.singleOrNull { it is Directive && it.directive == "%zeropage" }
+fun determineCompilationOptions(program: Program, compTarget: ICompilationTarget): CompilationOptions {
+    val toplevelModule = program.toplevelModule
+    val outputDirective = (toplevelModule.statements.singleOrNull { it is Directive && it.directive == "%output" } as? Directive)
+    val launcherDirective = (toplevelModule.statements.singleOrNull { it is Directive && it.directive == "%launcher" } as? Directive)
+    val outputTypeStr = outputDirective?.args?.single()?.name?.uppercase()
+    val launcherTypeStr = launcherDirective?.args?.single()?.name?.uppercase()
+    val zpoption: String? = (toplevelModule.statements.singleOrNull { it is Directive && it.directive == "%zeropage" }
             as? Directive)?.args?.single()?.name?.uppercase()
     val allOptions = program.modules.flatMap { it.statements }.filter { it is Directive && it.directive == "%option" }
         .flatMap { (it as Directive).args }.toSet()
@@ -224,139 +218,152 @@ private fun determineCompilationOptions(program: Program, compTarget: ICompilati
         zpType = ZeropageType.BASICSAFE
     }
 
-    val zpReserved = mainModule.statements
+    val zpReserved = toplevelModule.statements
         .asSequence()
         .filter { it is Directive && it.directive == "%zpreserved" }
         .map { (it as Directive).args }
         .map { it[0].int!!..it[1].int!! }
         .toList()
 
-    if (outputType != null && !OutputType.values().any { it.name == outputType }) {
-        System.err.println("invalid output type $outputType")
-        exitProcess(1)
+    val outputType = if (outputTypeStr == null) OutputType.PRG else {
+        try {
+            OutputType.valueOf(outputTypeStr)
+        } catch (x: IllegalArgumentException) {
+            // set default value; actual check and error handling of invalid option is handled in the AstChecker later
+            OutputType.PRG
+        }
     }
-    if (launcherType != null && !LauncherType.values().any { it.name == launcherType }) {
-        System.err.println("invalid launcher type $launcherType")
-        exitProcess(1)
+    val launcherType = if (launcherTypeStr == null) LauncherType.BASIC else {
+        try {
+            LauncherType.valueOf(launcherTypeStr)
+        } catch (x: IllegalArgumentException) {
+            // set default value; actual check and error handling of invalid option is handled in the AstChecker later
+            LauncherType.BASIC
+        }
     }
 
     return CompilationOptions(
-        if (outputType == null) OutputType.PRG else OutputType.valueOf(outputType),
-        if (launcherType == null) LauncherType.BASIC else LauncherType.valueOf(launcherType),
+        outputType,
+        launcherType,
         zpType, zpReserved, floatsEnabled, noSysInit,
         compTarget
     )
 }
 
-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()
+    program.checkIdentifiers(errors, compilerOptions)
     errors.report()
-    programAst.constantFold(errors, compilerOptions.compTarget)
+    // TODO: turning char literals into UBYTEs via an encoding should really happen in code gen - but for that we'd need DataType.CHAR
+    //       ...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.
+    program.charLiteralsToUByteLiterals(compilerOptions.compTarget)
+    program.constantFold(errors, compilerOptions.compTarget)
     errors.report()
-    programAst.reorderStatements(errors)
+    program.reorderStatements(errors)
     errors.report()
-    programAst.addTypecasts(errors)
+    program.addTypecasts(errors)
     errors.report()
-    programAst.variousCleanups(programAst, errors)
+    program.variousCleanups(program, errors)
     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()
+        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
     }
 
-    val inliner = SubroutineInliner(programAst, errors, options)
-    inliner.visit(programAst)
-    errors.report()
-    if(errors.noErrors()) {
-        inliner.applyModifications()
-        inliner.fixCallsToInlinedSubroutines()
-        val remover2 = UnusedCodeRemover(programAst, errors, compTarget)
-        remover2.visit(programAst)
-        remover2.applyModifications()
-    }
-
     errors.report()
 }
 
-private fun postprocessAst(programAst: Program, errors: IErrorReporter, compilerOptions: CompilationOptions) {
-    programAst.addTypecasts(errors)
+private fun postprocessAst(program: Program, errors: IErrorReporter, compilerOptions: CompilationOptions) {
+    program.addTypecasts(errors)
     errors.report()
-    programAst.variousCleanups(programAst, errors)
-    programAst.checkValid(compilerOptions, errors, compilerOptions.compTarget)          // check if final tree is still valid
+    program.variousCleanups(program, errors)
+    program.checkValid(errors, compilerOptions)          // check if final tree is still valid
     errors.report()
-    val callGraph = CallGraph(programAst)
+    val callGraph = CallGraph(program)
     callGraph.checkRecursiveCalls(errors)
     errors.report()
-    programAst.verifyFunctionArgTypes()
-    programAst.moveMainAndStartToFirst()
+    program.verifyFunctionArgTypes()
+    program.moveMainAndStartToFirst()
 }
 
-private fun writeAssembly(programAst: Program,
+private sealed class WriteAssemblyResult {
+    class Ok(val filename: String): WriteAssemblyResult()
+    class Fail(val error: String): WriteAssemblyResult()
+}
+
+private fun writeAssembly(program: Program,
                           errors: IErrorReporter,
                           outputDir: Path,
-                          compilerOptions: CompilationOptions): String {
+                          quietAssembler: Boolean,
+                          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 *************")
+//    printAst(program)
 
     compilerOptions.compTarget.machine.initializeZeropage(compilerOptions)
     val assembly = asmGeneratorFor(compilerOptions.compTarget,
-            programAst,
+            program,
             errors,
             compilerOptions.compTarget.machine.zeropage,
             compilerOptions,
             outputDir).compileToAssembly()
-    assembly.assemble(compilerOptions)
     errors.report()
-    return assembly.name
-}
 
-fun printAst(programAst: Program) {
-    println()
-    val printer = AstToSourceCode(::print, programAst)
-    printer.visit(programAst)
-    println()
-}
-
-fun loadAsmIncludeFile(filename: String, source: Path): String {
-    return if (filename.startsWith("library:")) {
-        val resource = tryGetEmbeddedResource(filename.substring(8))
-            ?: throw IllegalArgumentException("library file '$filename' not found")
-        resource.bufferedReader().use { it.readText() }
+    return if(assembly.valid && errors.noErrors()) {
+        val assemblerReturnStatus = assembly.assemble(quietAssembler, compilerOptions)
+        if(assemblerReturnStatus!=0)
+            WriteAssemblyResult.Fail("assembler step failed with return code $assemblerReturnStatus")
+        else {
+            WriteAssemblyResult.Ok(assembly.name)
+        }
     } else {
-        // first try in the isSameAs folder as where the containing file was imported from
-        val sib = source.resolveSibling(filename)
-        if (sib.toFile().isFile)
-            sib.toFile().readText()
-        else
-            File(filename).readText()
+        WriteAssemblyResult.Fail("compiler failed with errors")
     }
 }
 
-internal fun tryGetEmbeddedResource(name: String): InputStream? {
-    return object{}.javaClass.getResourceAsStream("/prog8lib/$name")
+fun printAst(program: Program) {
+    println()
+    val printer = AstToSourceTextConverter(::print, program)
+    printer.visit(program)
+    println()
+}
+
+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 {
+            val printer = when(it.severity) {
+                MessageSeverity.WARNING -> System.out
+                MessageSeverity.ERROR -> System.err
+            }
             when(it.severity) {
-                MessageSeverity.ERROR -> System.err.print("\u001b[91m")  // bright red
-                MessageSeverity.WARNING -> System.err.print("\u001b[93m")  // bright yellow
+                MessageSeverity.ERROR -> printer.print("\u001b[91m")  // bright red
+                MessageSeverity.WARNING -> printer.print("\u001b[93m")  // bright yellow
             }
             val msg = "${it.position.toClickableStr()} ${it.severity} ${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/ModuleImporter.kt

@@ -0,0 +1,159 @@
+package prog8.compiler
+
+import com.github.michaelbull.result.*
+import prog8.ast.Module
+import prog8.ast.Program
+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
+import java.nio.file.Path
+import kotlin.io.path.*
+
+
+class ModuleImporter(private val program: Program,
+                     private val compilationTargetName: String,
+                     val errors: IErrorReporter,
+                     sourceDirs: List<String>) {
+
+    private val sourcePaths: List<Path> = sourceDirs.map { Path(it) }
+
+    fun importModule(filePath: Path): Result<Module, NoSuchFileException> {
+        val currentDir = Path("").absolute()
+        val searchIn = listOf(currentDir) + sourcePaths
+        val candidates = searchIn
+            .map { it.absolute().div(filePath).normalize().absolute() }
+            .filter { it.exists() }
+            .map { currentDir.relativize(it) }
+            .map { if (it.isAbsolute) it else Path(".", "$it") }
+
+        val srcPath = when (candidates.size) {
+            0 -> return Err(NoSuchFileException(
+                    file = filePath.normalize().toFile(),
+                    reason = "Searched in $searchIn"))
+            1 -> candidates.first()
+            else -> candidates.first()  // when more candiates, pick the one from the first location
+        }
+
+        val logMsg = "importing '${filePath.nameWithoutExtension}' (from file $srcPath)"
+        println(logMsg)
+
+        val module = importModule(SourceCode.File(srcPath))
+        return if(module==null)
+            Err(NoSuchFileException(srcPath.toFile()))
+        else
+            Ok(module)
+    }
+
+    fun importLibraryModule(name: String): Module? {
+        val import = Directive("%import", listOf(
+                DirectiveArg("", name, 42, position = Position("<<<implicit-import>>>", 0, 0, 0))
+        ), Position("<<<implicit-import>>>", 0, 0, 0))
+        return executeImportDirective(import, null)
+    }
+
+    private fun importModule(src: SourceCode) : Module? {
+        val moduleAst = Prog8Parser.parseModule(src)
+        program.addModule(moduleAst)
+
+        // accept additional imports
+        try {
+            val lines = moduleAst.statements.toMutableList()
+            lines.asSequence()
+                .mapIndexed { i, it -> i to it }
+                .filter { (it.second as? Directive)?.directive == "%import" }
+                .forEach { executeImportDirective(it.second as Directive, moduleAst) }
+            moduleAst.statements = lines
+            return moduleAst
+        } catch (x: Exception) {
+            // in case of error, make sure the module we're importing is no longer in the Ast
+            program.removeModule(moduleAst)
+            throw x
+        }
+    }
+
+    private fun executeImportDirective(import: Directive, importingModule: Module?): Module? {
+        if(import.directive!="%import" || import.args.size!=1)
+            throw SyntaxError("invalid import directive", import.position)
+        if(!import.args[0].str.isNullOrEmpty() || import.args[0].name==null)
+            throw SyntaxError("%import requires unquoted module name", import.position)
+        val moduleName = import.args[0].name!!
+        if("$moduleName.p8" == import.position.file)
+            throw SyntaxError("cannot import self", import.position)
+
+        val existing = program.modules.singleOrNull { it.name == moduleName }
+        if (existing!=null)
+            return existing
+
+        // try internal library first
+        val moduleResourceSrc = getModuleFromResource("$moduleName.p8", compilationTargetName)
+        val importedModule =
+            moduleResourceSrc.fold(
+                success = {
+                    println("importing '$moduleName' (from internal ${it.origin})")
+                    importModule(it)
+                },
+                failure = {
+                    // try filesystem next
+                    val moduleSrc = getModuleFromFile(moduleName, importingModule)
+                    moduleSrc.fold(
+                        success = {
+                            println("importing '$moduleName' (from file ${it.origin})")
+                            importModule(it)
+                        },
+                        failure = {
+                            errors.err("no module found with name $moduleName. Searched in: $sourcePaths (and internal libraries)", import.position)
+                            return null
+                        }
+                    )
+                }
+            )
+
+        if(importedModule!=null)
+            removeDirectivesFromImportedModule(importedModule)
+        return importedModule
+    }
+
+    private fun removeDirectivesFromImportedModule(importedModule: Module) {
+        // Most global directives don't apply for imported modules, so remove them
+        val moduleLevelDirectives = listOf("%output", "%launcher", "%zeropage", "%zpreserved", "%address")
+        var directives = importedModule.statements.filterIsInstance<Directive>()
+        importedModule.statements.removeAll(directives)
+        directives = directives.filter{ it.directive !in moduleLevelDirectives }
+        importedModule.statements.addAll(0, directives)
+    }
+
+    private fun getModuleFromResource(name: String, compilationTargetName: String): Result<SourceCode, NoSuchFileException> {
+        val result =
+            runCatching { SourceCode.Resource("/prog8lib/$compilationTargetName/$name") }
+            .orElse { runCatching { SourceCode.Resource("/prog8lib/$name") }  }
+
+        return result.mapError { NoSuchFileException(File(name)) }
+    }
+
+    private fun getModuleFromFile(name: String, importingModule: Module?): Result<SourceCode, NoSuchFileException> {
+        val fileName = "$name.p8"
+        val locations =
+            if (importingModule == null) { // <=> imported from library module
+                sourcePaths
+            } else {
+                val dropCurDir = if(sourcePaths.isNotEmpty() && sourcePaths[0].name == ".") 1 else 0
+                sourcePaths.drop(dropCurDir) +
+                listOf(Path(importingModule.position.file).parent ?: Path("")) +
+                listOf(Path(".", "prog8lib"))
+            }
+
+        locations.forEach {
+            try {
+                return Ok(SourceCode.File(it.resolve(fileName)))
+            } catch (e: NoSuchFileException) {
+            }
+        }
+
+        return Err(NoSuchFileException(File("name")))
+    }
+}

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

@@ -1,28 +1,22 @@
 package prog8.compiler.astprocessing
 
 import prog8.ast.INameScope
+import prog8.ast.IStatementContainer
 import prog8.ast.Module
 import prog8.ast.Program
 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.C64Target
-import prog8.compiler.target.Cx16Target
-import prog8.compiler.target.ICompilationTarget
+import prog8.compilerinterface.*
 import java.io.CharConversionException
 import java.io.File
 import java.util.*
+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) {
@@ -32,7 +26,7 @@ internal class AstChecker(private val program: Program,
         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
@@ -45,8 +39,8 @@ internal class AstChecker(private val program: Program,
         }
 
         if(compilerOptions.floats) {
-            if (compilerOptions.zeropage !in setOf(ZeropageType.FLOATSAFE, ZeropageType.BASICSAFE, ZeropageType.DONTUSE ))
-                errors.err("when floats are enabled, zero page type should be 'floatsafe' or 'basicsafe' or 'dontuse'", program.mainModule.position)
+            if (compilerOptions.zeropage !in arrayOf(ZeropageType.FLOATSAFE, ZeropageType.BASICSAFE, ZeropageType.DONTUSE ))
+                errors.err("when floats are enabled, zero page type should be 'floatsafe' or 'basicsafe' or 'dontuse'", program.toplevelModule.position)
         }
 
         super.visit(program)
@@ -64,7 +58,7 @@ internal class AstChecker(private val program: Program,
     }
 
     override fun visit(returnStmt: Return) {
-        val expectedReturnValues = returnStmt.definingSubroutine()?.returntypes ?: emptyList()
+        val expectedReturnValues = returnStmt.definingSubroutine?.returntypes ?: emptyList()
         if(expectedReturnValues.size>1) {
             throw FatalAstException("cannot use a return with one value in a subroutine that has multiple return values: $returnStmt")
         }
@@ -80,7 +74,7 @@ internal class AstChecker(private val program: Program,
             if(!valueDt.isKnown) {
                 errors.err("return value type mismatch or unknown symbol", returnStmt.value!!.position)
             } else {
-                if (expectedReturnValues[0] != valueDt.typeOrElse(DataType.UNDEFINED))
+                if (expectedReturnValues[0] != valueDt.getOr(DataType.UNDEFINED))
                     errors.err("type $valueDt of return value doesn't match subroutine's return type ${expectedReturnValues[0]}", returnStmt.value!!.position)
             }
         }
@@ -88,7 +82,7 @@ internal class AstChecker(private val program: Program,
     }
 
     override fun visit(ifStatement: IfStatement) {
-        if(!ifStatement.condition.inferType(program).isInteger())
+        if(!ifStatement.condition.inferType(program).isInteger)
             errors.err("condition value should be an integer type", ifStatement.condition.position)
         super.visit(ifStatement)
     }
@@ -106,7 +100,7 @@ internal class AstChecker(private val program: Program,
             }
         }
 
-        val iterableDt = forLoop.iterable.inferType(program).typeOrElse(DataType.BYTE)
+        val iterableDt = forLoop.iterable.inferType(program).getOr(DataType.BYTE)
         if(iterableDt !in IterableDatatypes && forLoop.iterable !is RangeExpr) {
             errors.err("can only loop over an iterable type", forLoop.position)
         } else {
@@ -138,6 +132,9 @@ internal class AstChecker(private val program: Program,
                             errors.err("word loop variable can only loop over bytes or words", forLoop.position)
                     }
                     DataType.FLOAT -> {
+                        // Looping over float variables is very inefficient because the loopvar is going to
+                        // get copied over with new values all the time. We don't support this for now.
+                        // Loop with an integer index variable if you really need to... or write different code.
                         errors.err("for loop only supports integers", forLoop.position)
                     }
                     else -> errors.err("loop variable must be numeric type", forLoop.position)
@@ -150,11 +147,11 @@ internal class AstChecker(private val program: Program,
                         val to = range.to as? NumericLiteralValue
                         if(from != null)
                             checkValueTypeAndRange(loopvar.datatype, from)
-                        else if(!range.from.inferType(program).istype(loopvar.datatype))
+                        else if(range.from.inferType(program) isnot loopvar.datatype)
                             errors.err("range start value is incompatible with loop variable type", range.position)
                         if(to != null)
                             checkValueTypeAndRange(loopvar.datatype, to)
-                        else if(!range.to.inferType(program).istype(loopvar.datatype))
+                        else if(range.to.inferType(program) isnot loopvar.datatype)
                             errors.err("range end value is incompatible with loop variable type", range.position)
                     }
                 }
@@ -194,8 +191,12 @@ internal class AstChecker(private val program: Program,
                 is Label,
                 is VarDecl,
                 is InlineAssembly,
-                is INameScope,
+                is IStatementContainer,
                 is NopStatement -> true
+                is Assignment -> {
+                    val target = statement.target.identifier!!.targetStatement(program)
+                    target === statement.previousSibling()      // an initializer assignment is okay
+                }
                 else -> false
             }
             if (!ok) {
@@ -215,7 +216,7 @@ internal class AstChecker(private val program: Program,
         super.visit(label)
     }
 
-    private fun hasReturnOrJump(scope: INameScope): Boolean {
+    private fun hasReturnOrJump(scope: IStatementContainer): Boolean {
         class Searcher: IAstVisitor
         {
             var count=0
@@ -243,8 +244,8 @@ 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)
@@ -269,10 +270,11 @@ internal class AstChecker(private val program: Program,
             }
         }
 
-        // scope check
-        if(subroutine.parent !is Block && subroutine.parent !is Subroutine) {
+        if(subroutine.inline && !subroutine.isAsmSubroutine)
+            err("subroutine inlining is currently only supported on asmsub routines")
+
+        if(subroutine.parent !is Block && subroutine.parent !is Subroutine)
             err("subroutines can only be defined in the scope of a block or within another subroutine")
-        }
 
         if(subroutine.isAsmSubroutine) {
             if(subroutine.asmParameterRegisters.size != subroutine.parameters.size)
@@ -280,14 +282,14 @@ internal class AstChecker(private val program: Program,
             if(subroutine.asmReturnvaluesRegisters.size != subroutine.returntypes.size)
                 err("number of return registers is not the isSameAs as number of return values")
             for(param in subroutine.parameters.zip(subroutine.asmParameterRegisters)) {
-                if(param.second.registerOrPair in setOf(RegisterOrPair.A, RegisterOrPair.X, RegisterOrPair.Y)) {
+                if(param.second.registerOrPair in arrayOf(RegisterOrPair.A, RegisterOrPair.X, RegisterOrPair.Y)) {
                     if (param.first.type != DataType.UBYTE && param.first.type != DataType.BYTE)
                         err("parameter '${param.first.name}' should be (u)byte")
                 }
-                else if(param.second.registerOrPair in setOf(RegisterOrPair.AX, RegisterOrPair.AY, RegisterOrPair.XY)) {
+                else if(param.second.registerOrPair in arrayOf(RegisterOrPair.AX, RegisterOrPair.AY, RegisterOrPair.XY)) {
                     if (param.first.type != DataType.UWORD && param.first.type != DataType.WORD
                             && param.first.type != DataType.STR && param.first.type !in ArrayDatatypes && param.first.type != DataType.FLOAT)
-                        err("parameter '${param.first.name}' should be (u)word/address")
+                        err("parameter '${param.first.name}' should be (u)word (an address) or str")
                 }
                 else if(param.second.statusflag!=null) {
                     if (param.first.type != DataType.UBYTE)
@@ -295,11 +297,11 @@ internal class AstChecker(private val program: Program,
                 }
             }
             subroutine.returntypes.zip(subroutine.asmReturnvaluesRegisters).forEachIndexed { index, pair ->
-                if(pair.second.registerOrPair in setOf(RegisterOrPair.A, RegisterOrPair.X, RegisterOrPair.Y)) {
+                if(pair.second.registerOrPair in arrayOf(RegisterOrPair.A, RegisterOrPair.X, RegisterOrPair.Y)) {
                     if (pair.first != DataType.UBYTE && pair.first != DataType.BYTE)
                         err("return value #${index + 1} should be (u)byte")
                 }
-                else if(pair.second.registerOrPair in setOf(RegisterOrPair.AX, RegisterOrPair.AY, RegisterOrPair.XY)) {
+                else if(pair.second.registerOrPair in arrayOf(RegisterOrPair.AX, RegisterOrPair.AY, RegisterOrPair.XY)) {
                     if (pair.first != DataType.UWORD && pair.first != DataType.WORD
                             && pair.first != DataType.STR && pair.first !in ArrayDatatypes && pair.first != DataType.FLOAT)
                         err("return value #${index + 1} should be (u)word/address")
@@ -379,22 +381,24 @@ internal class AstChecker(private val program: Program,
                 err("can only use Carry as status flag parameter")
 
         } else {
-            // Pass-by-reference datatypes can not occur as parameters to a subroutine directly
+            // Non-string 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.")
+            for(p in subroutine.parameters) {
+                if(p.type in PassByReferenceDatatypes && p.type != DataType.STR) {
+                    err("Non-string pass-by-reference types cannot occur as a parameter type directly. Instead, use an uword to receive their address, or access the variable from the outer scope directly.")
+                }
             }
         }
     }
 
     override fun visit(untilLoop: UntilLoop) {
-        if(!untilLoop.condition.inferType(program).isInteger())
+        if(!untilLoop.condition.inferType(program).isInteger)
             errors.err("condition value should be an integer type", untilLoop.condition.position)
         super.visit(untilLoop)
     }
 
     override fun visit(whileLoop: WhileLoop) {
-        if(!whileLoop.condition.inferType(program).isInteger())
+        if(!whileLoop.condition.inferType(program).isInteger)
             errors.err("condition value should be an integer type", whileLoop.condition.position)
         super.visit(whileLoop)
     }
@@ -414,7 +418,7 @@ internal class AstChecker(private val program: 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.typeOrElse(DataType.BYTE))) {
+                if(stmt.returntypes.isEmpty() || (stmt.returntypes.size == 1 && stmt.returntypes.single() isNotAssignableTo idt.getOr(DataType.BYTE))) {
                     errors.err("return type mismatch", assignment.value.position)
                 }
             }
@@ -423,14 +427,14 @@ internal class AstChecker(private val program: Program,
         val targetDt = assignment.target.inferType(program)
         val valueDt = assignment.value.inferType(program)
         if(valueDt.isKnown && !(valueDt isAssignableTo targetDt)) {
-            if(targetDt.isIterable())
+            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)))
+            else if(!(valueDt istype DataType.STR && targetDt istype DataType.UWORD))
                 errors.err("type of value doesn't match target", assignment.value.position)
         }
 
         if(assignment.value is TypecastExpression) {
-            if(assignment.isAugmentable && targetDt.istype(DataType.FLOAT))
+            if(assignment.isAugmentable && targetDt istype DataType.FLOAT)
                 errors.err("typecasting a float value in-place makes no sense", assignment.value.position)
         }
 
@@ -450,7 +454,7 @@ 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
@@ -479,15 +483,15 @@ internal class AstChecker(private val program: Program,
             if (targetDatatype.isKnown) {
                 val constVal = assignment.value.constValue(program)
                 if (constVal != null) {
-                    checkValueTypeAndRange(targetDatatype.typeOrElse(DataType.BYTE), constVal)
+                    checkValueTypeAndRange(targetDatatype.getOr(DataType.BYTE), constVal)
                 } else {
                     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)
                     } else {
-                        checkAssignmentCompatible(targetDatatype.typeOrElse(DataType.BYTE), assignTarget,
-                                sourceDatatype.typeOrElse(DataType.BYTE), assignment.value, assignment.position)
+                        checkAssignmentCompatible(targetDatatype.getOr(DataType.BYTE), assignTarget,
+                                sourceDatatype.getOr(DataType.BYTE), assignment.value, assignment.position)
                     }
                 }
             }
@@ -502,7 +506,7 @@ 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)
@@ -515,7 +519,7 @@ internal class AstChecker(private val program: Program,
         }
 
         // FLOATS enabled?
-        if(!compilerOptions.floats && decl.datatype in setOf(DataType.FLOAT, DataType.ARRAY_F) && decl.type!= VarDeclType.MEMORY)
+        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))
@@ -583,18 +587,18 @@ 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?")
                 }
             }
         }
 
         val declValue = decl.value
         if(declValue!=null && decl.type==VarDeclType.VAR) {
-            if (!declValue.inferType(program).istype(decl.datatype)) {
-                err("initialisation value has incompatible type (${declValue.inferType(program)}) for the variable (${decl.datatype})", declValue.position)
+            if (declValue.inferType(program) isnot decl.datatype) {
+                err("initialisation value has incompatible type (${declValue.inferType(program)}) for the variable (${decl.datatype})")
             }
         }
 
@@ -623,10 +627,13 @@ 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")
+            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")
+            }
             else if (decl.type==VarDeclType.VAR && decl.value !is StringLiteralValue)
                 err("string var can only be initialized with a string literal")
         }
@@ -711,37 +718,37 @@ internal class AstChecker(private val program: Program,
                     err("this directive may only occur in a block or at module level")
                 if(directive.args.isEmpty())
                     err("missing option directive argument(s)")
-                else if(directive.args.map{it.name in setOf("enable_floats", "force_output", "no_sysinit", "align_word", "align_page")}.any { !it })
+                else if(directive.args.map{it.name in arrayOf("enable_floats", "force_output", "no_sysinit", "align_word", "align_page")}.any { !it })
                     err("invalid option directive argument(s)")
             }
-            "%target" -> {
-                if(directive.parent !is Block && directive.parent !is Module)
-                    err("this directive may only occur in a block or at module level")
-                if(directive.args.size != 1)
-                    err("directive requires one argument")
-                if(directive.args.single().name !in setOf(C64Target.name, Cx16Target.name))
-                    err("invalid compilation target")
-            }
             else -> throw SyntaxError("invalid directive ${directive.directive}", directive.position)
         }
         super.visit(directive)
     }
 
     private fun checkFileExists(directive: Directive, filename: String) {
-        var definingModule = directive.parent
-        while (definingModule !is Module)
-            definingModule = definingModule.parent
-        if (!(filename.startsWith("library:") || definingModule.source.resolveSibling(filename).toFile().isFile || File(filename).isFile))
+        if (File(filename).isFile)
+            return
+
+        val definingModule = directive.definingModule
+        if (definingModule.isLibrary || !definingModule.source.isFromFilesystem)
+            return
+
+        val s = definingModule.source.origin
+        val sourceFileCandidate = Path(s).resolveSibling(filename).toFile()
+        if (sourceFileCandidate.isFile)
+            return
+        else
             errors.err("included file not found: $filename", directive.position)
     }
 
     override fun visit(array: ArrayLiteralValue) {
         if(array.type.isKnown) {
-            if (!compilerOptions.floats && array.type.typeOrElse(DataType.UNDEFINED) in setOf(DataType.FLOAT, DataType.ARRAY_F)) {
+            if (!compilerOptions.floats && array.type.oneOf(DataType.FLOAT, DataType.ARRAY_F)) {
                 errors.err("floating point used, but that is not enabled via options", array.position)
             }
             val arrayspec = ArrayIndex.forArray(array)
-            checkValueTypeAndRangeArray(array.type.typeOrElse(DataType.UNDEFINED), arrayspec, array)
+            checkValueTypeAndRangeArray(array.type.getOr(DataType.UNDEFINED), arrayspec, array)
         }
 
         fun isPassByReferenceElement(e: Expression): Boolean {
@@ -763,11 +770,21 @@ internal class AstChecker(private val program: Program,
         super.visit(array)
     }
 
+    override fun visit(char: CharLiteral) {
+        try {  // just *try* if it can be encoded, don't actually do it
+            compilerOptions.compTarget.encodeString(char.value.toString(), char.altEncoding)
+        } catch (cx: CharConversionException) {
+            errors.err(cx.message ?: "can't encode character", char.position)
+        }
+
+        super.visit(char)
+    }
+
     override fun visit(string: StringLiteralValue) {
         checkValueTypeAndRangeString(DataType.STR, string)
 
-        try {
-            compTarget.encodeString(string.value, string.altEncoding)
+        try {  // just *try* if it can be encoded, don't actually do it
+            compilerOptions.compTarget.encodeString(string.value, string.altEncoding)
         } catch (cx: CharConversionException) {
             errors.err(cx.message ?: "can't encode string", string.position)
         }
@@ -776,11 +793,10 @@ 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.typeOrElse(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)
@@ -805,8 +821,8 @@ internal class AstChecker(private val program: Program,
         if(!leftIDt.isKnown || !rightIDt.isKnown)
             return     // hopefully this error will be detected elsewhere
 
-        val leftDt = leftIDt.typeOrElse(DataType.UNDEFINED)
-        val rightDt = rightIDt.typeOrElse(DataType.UNDEFINED)
+        val leftDt = leftIDt.getOr(DataType.UNDEFINED)
+        val rightDt = rightIDt.getOr(DataType.UNDEFINED)
 
         when(expr.operator){
             "/", "%" -> {
@@ -902,7 +918,7 @@ internal class AstChecker(private val program: Program,
         // warn about sgn(unsigned) this is likely a mistake
         if(functionCall.target.nameInSource.last()=="sgn") {
             val sgnArgType = functionCall.args.first().inferType(program)
-            if(sgnArgType.istype(DataType.UBYTE) || sgnArgType.istype(DataType.UWORD))
+            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)
         }
 
@@ -971,12 +987,12 @@ internal class AstChecker(private val program: Program,
         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)) {
+            if(idref!=null && idref.inferType(program) istype DataType.ARRAY_F) {
                 errors.err("sorting a floating point array is not supported", functionCallStatement.args.first().position)
             }
         }
 
-        if(functionCallStatement.target.nameInSource.last() in setOf("rol", "ror", "rol2", "ror2", "swap", "sort", "reverse")) {
+        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)
@@ -998,7 +1014,7 @@ internal class AstChecker(private val program: Program,
 
         if(target is BuiltinFunctionStatementPlaceholder) {
             if(target.name=="swap") {
-                // swap() is a bit weird because this one is translated into a operations directly, instead of being a function call
+                // 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)
                 val dt2 = args[1].inferType(program)
                 if (dt1 != dt2)
@@ -1007,14 +1023,14 @@ internal class AstChecker(private val program: Program,
                     errors.err("swap requires 2 variables, not constant value(s)", position)
                 else if(args[0] isSameAs args[1])
                     errors.err("swap should have 2 different args", position)
-                else if(!dt1.isNumeric())
+                else if(!dt1.isNumeric)
                     errors.err("swap requires args of numerical type", position)
             }
             else if(target.name=="all" || target.name=="any") {
                 if((args[0] as? AddressOf)?.identifier?.targetVarDecl(program)?.datatype == DataType.STR) {
                     errors.err("any/all on a string is useless (is always true unless the string is empty)", position)
                 }
-                if(args[0].inferType(program).typeOrElse(DataType.STR) == DataType.STR) {
+                if(args[0].inferType(program).getOr(DataType.STR) == DataType.STR) {
                     errors.err("any/all on a string is useless (is always true unless the string is empty)", position)
                 }
             }
@@ -1054,7 +1070,7 @@ 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)
@@ -1105,14 +1121,14 @@ internal class AstChecker(private val program: Program,
 
         // check index value 0..255
         val dtxNum = arrayIndexedExpression.indexer.indexExpr.inferType(program)
-        if(!dtxNum.istype(DataType.UBYTE) && !dtxNum.istype(DataType.BYTE))
+        if(dtxNum isnot DataType.UBYTE && dtxNum isnot DataType.BYTE)
             errors.err("array indexing is limited to byte size 0..255", arrayIndexedExpression.position)
 
         super.visit(arrayIndexedExpression)
     }
 
     override fun visit(whenStatement: WhenStatement) {
-        if(!whenStatement.condition.inferType(program).isInteger())
+        if(!whenStatement.condition.inferType(program).isInteger)
             errors.err("when condition must be an integer value", whenStatement.position)
         val tally = mutableSetOf<Int>()
         for((choices, choiceNode) in whenStatement.choiceValues(program)) {
@@ -1143,7 +1159,7 @@ internal class AstChecker(private val program: Program,
                 when {
                     constvalue == null -> errors.err("choice value must be a constant", whenChoice.position)
                     constvalue.type !in IntegerDatatypes -> errors.err("choice value must be a byte or word", whenChoice.position)
-                    constvalue.type != conditionType.typeOrElse(DataType.UNDEFINED) -> errors.err("choice value datatype differs from condition value", whenChoice.position)
+                    conditionType isnot constvalue.type -> errors.err("choice value datatype differs from condition value", whenChoice.position)
                 }
             }
         } else {
@@ -1154,13 +1170,11 @@ internal class AstChecker(private val program: Program,
     }
 
     private fun checkFunctionOrLabelExists(target: IdentifierReference, statement: Statement): Statement? {
-        val targetStatement = target.targetStatement(program)
-        if(targetStatement is Label || targetStatement is Subroutine || targetStatement is BuiltinFunctionStatementPlaceholder)
-            return targetStatement
-        else if(targetStatement==null)
-            errors.err("undefined function or subroutine: ${target.nameInSource.joinToString(".")}", statement.position)
-        else
-            errors.err("cannot call that: ${target.nameInSource.joinToString(".")}", statement.position)
+        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)
+        }
         return null
     }
 
@@ -1189,7 +1203,7 @@ internal class AstChecker(private val program: Program,
             DataType.STR -> return err("string value expected")
             DataType.ARRAY_UB, DataType.ARRAY_B -> {
                 // value may be either a single byte, or a byte arraysize (of all constant values), or a range
-                if(value.type.istype(targetDt)) {
+                if(value.type istype targetDt) {
                     if(!checkArrayValues(value, targetDt))
                         return false
                     val arraySpecSize = arrayspec.constIndex()
@@ -1208,7 +1222,7 @@ internal class AstChecker(private val program: Program,
             }
             DataType.ARRAY_UW, DataType.ARRAY_W -> {
                 // value may be either a single word, or a word arraysize, or a range
-                if(value.type.istype(targetDt)) {
+                if(value.type istype targetDt) {
                     if(!checkArrayValues(value, targetDt))
                         return false
                     val arraySpecSize = arrayspec.constIndex()
@@ -1227,7 +1241,7 @@ internal class AstChecker(private val program: Program,
             }
             DataType.ARRAY_F -> {
                 // value may be either a single float, or a float arraysize
-                if(value.type.istype(targetDt)) {
+                if(value.type istype targetDt) {
                     if(!checkArrayValues(value, targetDt))
                         return false
                     val arraySize = value.value.size
@@ -1243,7 +1257,7 @@ 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
                 }

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

@@ -1,21 +1,27 @@
 package prog8.compiler.astprocessing
 
+import prog8.ast.Node
 import prog8.ast.Program
-import prog8.ast.base.FatalAstException
+import prog8.ast.base.DataType
+import prog8.ast.expressions.CharLiteral
+import prog8.ast.expressions.IdentifierReference
+import prog8.ast.expressions.NumericLiteralValue
 import prog8.ast.statements.Directive
+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.target.ICompilationTarget
+import prog8.compilerinterface.CompilationOptions
+import prog8.compilerinterface.IErrorReporter
+import prog8.compilerinterface.IStringEncoding
 
 
-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 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 = BeforeAsmGenerationAstChanger(this, compilerOptions, errors)
     fixer.visit(this)
     while(errors.noErrors() && fixer.applyModifications()>0) {
         fixer.visit(this)
@@ -33,6 +39,20 @@ internal fun Program.reorderStatements(errors: IErrorReporter) {
     }
 }
 
+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),
+                parent
+            ))
+        }
+    }
+    walker.visit(this)
+    walker.applyModifications()
+}
+
 internal fun Program.addTypecasts(errors: IErrorReporter) {
     val caster = TypecastsAdder(this, errors)
     caster.visit(this)
@@ -44,9 +64,17 @@ internal fun Program.verifyFunctionArgTypes() {
     fixer.visit(this)
 }
 
+internal fun Program.preprocessAst() {
+    val transforms = AstPreprocessor()
+    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, options.compTarget)
     checker2.visit(this)
 
     if(errors.noErrors()) {
@@ -57,10 +85,6 @@ internal fun Program.checkIdentifiers(errors: IErrorReporter, options: Compilati
         lit2decl.visit(this)
         lit2decl.applyModifications()
     }
-
-    if (modules.map { it.name }.toSet().size != modules.size) {
-        throw FatalAstException("modules should all be unique")
-    }
 }
 
 internal fun Program.variousCleanups(program: Program, errors: IErrorReporter) {
@@ -70,19 +94,16 @@ internal fun Program.variousCleanups(program: Program, errors: IErrorReporter) {
         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,
     // and finally the entrypoint subroutine "start" itself is moved to the top in that block.
 
     val directives = modules[0].statements.filterIsInstance<Directive>()
-    val start = this.entrypoint()
-    val mod = start.definingModule()
-    val block = start.definingBlock()
-    if(!modules.remove(mod))
-        throw FatalAstException("module wrong")
-    modules.add(0, mod)
+    val start = this.entrypoint
+    val mod = start.definingModule
+    val block = start.definingBlock
+    moveModuleToFront(mod)
     mod.remove(block)
     var afterDirective = mod.statements.indexOfFirst { it !is Directive }
     if(afterDirective<0)
@@ -102,3 +123,11 @@ internal fun Program.moveMainAndStartToFirst() {
         modules[0].statements.add(0, directive)
     }
 }
+
+internal fun IdentifierReference.isSubroutineParameter(program: Program): Boolean {
+    val vardecl = this.targetVarDecl(program)
+    if(vardecl!=null && vardecl.autogeneratedDontRemove) {
+        return vardecl.definingSubroutine?.parameters?.any { it.name==vardecl.name } == true
+    }
+    return false
+}

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

@@ -1,58 +1,37 @@
 package prog8.compiler.astprocessing
 
-import prog8.ast.Module
-import prog8.ast.Program
 import prog8.ast.base.Position
 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.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 compTarget: ICompilationTarget) : IAstVisitor {
     private var blocks = mutableMapOf<String, Block>()
 
     private fun nameError(name: String, position: Position, existing: Statement) {
         errors.err("name conflict '$name', also defined in ${existing.position.file} line ${existing.position.line}", position)
     }
 
-    override fun visit(module: Module) {
-        blocks.clear()  // blocks may be redefined within a different module
-
-        super.visit(module)
-    }
-
     override fun visit(block: Block) {
         if(block.name in compTarget.machine.opcodeNames)
             errors.err("can't use a cpu opcode name as a symbol: '${block.name}'", block.position)
 
         val existing = blocks[block.name]
-        if(existing!=null)
-            nameError(block.name, block.position, existing)
+        if(existing!=null) {
+            if(block.isInLibrary)
+                nameError(existing.name, existing.position, block)
+            else
+                nameError(block.name, block.position, existing)
+        }
         else
             blocks[block.name] = block
 
-        if(!block.isInLibrary) {
-            val libraries = program.modules.filter { it.isLibraryModule }
-            val libraryBlockNames = libraries.flatMap { it.statements.filterIsInstance<Block>().map { b -> b.name } }
-            if(block.name in libraryBlockNames)
-                errors.err("block is already defined in an included library module", block.position)
-        }
-
         super.visit(block)
     }
 
-    override fun visit(directive: Directive) {
-        if(directive.directive=="%target") {
-            val compatibleTarget = directive.args.single().name
-            if (compatibleTarget != compTarget.name)
-                errors.err("module's compilation target ($compatibleTarget) differs from active target (${compTarget.name})", directive.position)
-        }
-
-        super.visit(directive)
-    }
-
     override fun visit(decl: VarDecl) {
         decl.datatypeErrors.forEach { errors.err(it.message, it.position) }
 
@@ -62,14 +41,14 @@ 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)
 
-        if(decl.definingBlock().name==decl.name)
-            nameError(decl.name, decl.position, decl.definingBlock())
-        if(decl.definingSubroutine()?.name==decl.name)
-            nameError(decl.name, decl.position, decl.definingSubroutine()!!)
+        if(decl.definingBlock.name==decl.name)
+            nameError(decl.name, decl.position, decl.definingBlock)
+        if(decl.definingSubroutine?.name==decl.name)
+            nameError(decl.name, decl.position, decl.definingSubroutine!!)
 
         super.visit(decl)
     }
@@ -85,32 +64,29 @@ 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.
-            val symbolsInSub = subroutine.allDefinedSymbols()
+            // 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.position != subroutine.position)
+                    nameError(name, symbol.position, subroutine)
             }
 
             if(subroutine.isAsmSubroutine && subroutine.statements.any{it !is InlineAssembly}) {
                 errors.err("asmsub can only contain inline assembly (%asm)", subroutine.position)
             }
 
-            if(subroutine.name == subroutine.definingBlock().name) {
+            if(subroutine.name == subroutine.definingBlock.name) {
                 // subroutines cannot have the same name as their enclosing block,
                 // because this causes symbol scoping issues in the resulting assembly source
-                nameError(subroutine.name, subroutine.position, subroutine.definingBlock())
+                nameError(subroutine.name, subroutine.position, subroutine.definingBlock)
             }
         }
 
@@ -125,7 +101,7 @@ internal class AstIdentifiersChecker(private val program: Program, private val e
             // the builtin functions can't be redefined
             errors.err("builtin function cannot be redefined", label.position)
         } else {
-            val existing = label.definingSubroutine()?.getAllLabels(label.name) ?: emptyList()
+            val existing = label.definingSubroutine?.getAllLabels(label.name) ?: emptyList()
             for(el in existing) {
                 if(el === label || el.name != label.name)
                     continue

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

@@ -0,0 +1,48 @@
+package prog8.compiler.astprocessing
+
+import prog8.ast.Node
+import prog8.ast.base.NumericDatatypes
+import prog8.ast.base.VarDeclType
+import prog8.ast.expressions.IdentifierReference
+import prog8.ast.statements.AnonymousScope
+import prog8.ast.statements.AssignTarget
+import prog8.ast.statements.Assignment
+import prog8.ast.statements.VarDecl
+import prog8.ast.walk.AstWalker
+import prog8.ast.walk.IAstModification
+
+
+class AstPreprocessor : AstWalker() {
+
+    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.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!!, 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
+    }
+}

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

@@ -17,7 +17,7 @@ internal class AstVariousTransforms(private val program: Program) : AstWalker()
     override fun after(subroutine: Subroutine, parent: Node): Iterable<IAstModification> {
         // For non-kernal subroutines and non-asm parameters:
         // inject subroutine params as local variables (if they're not there yet).
-        val symbolsInSub = subroutine.allDefinedSymbols()
+        val symbolsInSub = subroutine.allDefinedSymbols
         val namesInSub = symbolsInSub.map{ it.first }.toSet()
         if(subroutine.asmAddress==null) {
             if(subroutine.asmParameterRegisters.isEmpty() && subroutine.parameters.isNotEmpty()) {
@@ -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? {
@@ -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/LiteralsToAutoVars.kt

@@ -1,5 +1,6 @@
 package prog8.compiler.astprocessing
 
+import prog8.ast.IStatementContainer
 import prog8.ast.Node
 import prog8.ast.Program
 import prog8.ast.base.DataType
@@ -16,7 +17,7 @@ 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) {
-            // replace the literal string by a identifier reference to the interned string
+            // replace the literal string by an identifier reference to the interned string
             val scopedName = program.internString(string)
             val identifier = IdentifierReference(scopedName, string.position)
             return listOf(IAstModification.ReplaceNode(string, identifier, parent))
@@ -29,7 +30,7 @@ internal class LiteralsToAutoVars(private val program: Program) : AstWalker() {
         if(vardecl!=null) {
             // adjust the datatype of the array (to an educated guess)
             val arrayDt = array.type
-            if(!arrayDt.istype(vardecl.datatype)) {
+            if(arrayDt isnot vardecl.datatype) {
                 val cast = array.cast(vardecl.datatype)
                 if (cast != null && cast !== array)
                     return listOf(IAstModification.ReplaceNode(vardecl.value!!, cast, vardecl))
@@ -38,13 +39,15 @@ internal class LiteralsToAutoVars(private val program: Program) : AstWalker() {
             val arrayDt = array.guessDatatype(program)
             if(arrayDt.isKnown) {
                 // this array literal is part of an expression, turn it into an identifier reference
-                val litval2 = array.cast(arrayDt.typeOrElse(DataType.UNDEFINED))
+                val litval2 = array.cast(arrayDt.getOr(DataType.UNDEFINED))
                 if(litval2!=null) {
+                    if(array.parent !is IStatementContainer)
+                        return noModifications
                     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.InsertFirst(vardecl2, array.parent as IStatementContainer)
                     )
                 }
             }

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

@@ -1,17 +1,13 @@
 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.IErrorReporter
 
 
 internal class StatementReorderer(val program: Program, val errors: IErrorReporter) : AstWalker() {
@@ -24,7 +20,7 @@ internal class StatementReorderer(val program: Program, val errors: IErrorReport
     // - (syntax desugaring) a vardecl with a non-const initializer value is split into a regular vardecl and an assignment statement.
     // - 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).
+    // - insert AddressOf (&) expression where required (string params to a UWORD function param etc.).
 
     private val directivesToMove = setOf("%output", "%launcher", "%zeropage", "%zpreserved", "%address", "%option")
 
@@ -38,15 +34,62 @@ internal class StatementReorderer(val program: Program, val errors: IErrorReport
             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 && decl.datatype in NumericDatatypes) {
+            if(decl !in declsProcessedWithInitAssignment) {
+                declsProcessedWithInitAssignment.add(decl)
+                if (decl.value == null) {
+                    if (!decl.autogeneratedDontRemove && 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.
+                            // TODO these variables are no longer used???
+                            return noModifications
+                        }
+                        val nextStmt  = decl.nextSibling()
+                        val nextAssign = nextStmt as? Assignment
+                        val nextFor = nextStmt as? ForLoop
+                        val hasNextForWithThisLoopvar = nextFor?.loopVar?.nameInSource==listOf(decl.name)
+                        val hasNextAssignment = nextAssign!=null && nextAssign.target isSameAs IdentifierReference(listOf(decl.name), Position.DUMMY)
+                        if (!hasNextAssignment && !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(), 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!!, 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)
@@ -61,7 +104,7 @@ internal class StatementReorderer(val program: Program, val errors: IErrorReport
             )
         }
 
-        reorderVardeclsAndDirectives(block.statements)
+        directivesToTheTop(block.statements)
         return noModifications
     }
 
@@ -86,14 +129,19 @@ internal class StatementReorderer(val program: Program, val errors: IErrorReport
     }
 
     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> {
 
         // 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.)
+        //  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)
             return listOf(IAstModification.SwapOperands(expr))
 
@@ -106,12 +154,12 @@ internal class StatementReorderer(val program: Program, val errors: IErrorReport
                 is Assignment -> {
                     val targetDt = parent.target.inferType(program)
                     if(leftDt != targetDt) {
-                        val cast = TypecastExpression(expr.left, targetDt.typeOrElse(DataType.UNDEFINED), true, parent.position)
+                        val cast = TypecastExpression(expr.left, targetDt.getOr(DataType.UNDEFINED), true, parent.position)
                         return listOf(IAstModification.ReplaceNode(expr.left, cast, expr))
                     }
                 }
                 is VarDecl -> {
-                    if(!leftDt.istype(parent.datatype)) {
+                    if(leftDt isnot parent.datatype) {
                         val cast = TypecastExpression(expr.left, parent.datatype, true, parent.position)
                         return listOf(IAstModification.ReplaceNode(expr.left, cast, expr))
                     }
@@ -190,7 +238,7 @@ internal class StatementReorderer(val program: Program, val errors: IErrorReport
         val valueType = assignment.value.inferType(program)
         val targetType = assignment.target.inferType(program)
 
-        if(targetType.isArray() && valueType.isArray() ) {
+        if(targetType.isArray && valueType.isArray) {
             if (assignment.value is ArrayLiteralValue) {
                 errors.err("cannot assign array literal here, use separate assignment per element", assignment.position)
             } else {

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

@@ -8,8 +8,8 @@ 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.IErrorReporter
 
 
 class TypecastsAdder(val program: Program, val errors: IErrorReporter) : AstWalker() {
@@ -22,10 +22,10 @@ class TypecastsAdder(val program: Program, val errors: IErrorReporter) : AstWalk
         val declValue = decl.value
         if(decl.type==VarDeclType.VAR && declValue!=null) {
             val valueDt = declValue.inferType(program)
-            if(!valueDt.istype(decl.datatype)) {
+            if(valueDt isnot decl.datatype) {
 
                 // don't add a typecast on an array initializer value
-                if(valueDt.isInteger() && decl.datatype in ArrayDatatypes)
+                if(valueDt.isInteger && decl.datatype in ArrayDatatypes)
                     return noModifications
 
                 // don't add a typecast if the initializer value is inherently not assignable
@@ -47,7 +47,7 @@ class TypecastsAdder(val program: Program, val errors: IErrorReporter) : AstWalk
         val rightDt = expr.right.inferType(program)
         if(leftDt.isKnown && rightDt.isKnown && leftDt!=rightDt) {
             // determine common datatype and add typecast as required to make left and right equal types
-            val (commonDt, toFix) = BinaryExpression.commonDatatype(leftDt.typeOrElse(DataType.UNDEFINED), rightDt.typeOrElse(DataType.UNDEFINED), expr.left, expr.right)
+            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(
@@ -66,8 +66,8 @@ class TypecastsAdder(val program: Program, val errors: IErrorReporter) : AstWalk
         val valueItype = assignment.value.inferType(program)
         val targetItype = assignment.target.inferType(program)
         if(targetItype.isKnown && valueItype.isKnown) {
-            val targettype = targetItype.typeOrElse(DataType.UNDEFINED)
-            val valuetype = valueItype.typeOrElse(DataType.UNDEFINED)
+            val targettype = targetItype.getOr(DataType.UNDEFINED)
+            val valuetype = valueItype.getOr(DataType.UNDEFINED)
             if (valuetype != targettype) {
                 if (valuetype isAssignableTo targettype) {
                     if(valuetype in IterableDatatypes && targettype==DataType.UWORD)
@@ -78,10 +78,10 @@ class TypecastsAdder(val program: Program, val errors: IErrorReporter) : AstWalk
                             TypecastExpression(assignment.value, targettype, true, assignment.value.position),
                             assignment))
                 } 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()
                     }
@@ -126,7 +126,7 @@ class TypecastsAdder(val program: Program, val errors: IErrorReporter) : AstWalk
                 sub.parameters.zip(call.args).forEachIndexed { index, pair ->
                     val argItype = pair.second.inferType(program)
                     if(argItype.isKnown) {
-                        val argtype = argItype.typeOrElse(DataType.UNDEFINED)
+                        val argtype = argItype.getOr(DataType.UNDEFINED)
                         val requiredType = pair.first.type
                         if (requiredType != argtype) {
                             if (argtype isAssignableTo requiredType) {
@@ -135,11 +135,13 @@ class TypecastsAdder(val program: Program, val errors: IErrorReporter) : AstWalk
                                         TypecastExpression(pair.second, requiredType, true, pair.second.position),
                                         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),
+                                            AddressOf(identifier, pair.second.position),
                                             call as Node)
                                 }
                             } else if(pair.second is NumericLiteralValue) {
@@ -159,7 +161,7 @@ class TypecastsAdder(val program: Program, val errors: IErrorReporter) : AstWalk
                 func.parameters.zip(call.args).forEachIndexed { index, pair ->
                     val argItype = pair.second.inferType(program)
                     if (argItype.isKnown) {
-                        val argtype = argItype.typeOrElse(DataType.UNDEFINED)
+                        val argtype = argItype.getOr(DataType.UNDEFINED)
                         if (pair.first.possibleDatatypes.all { argtype != it }) {
                             for (possibleType in pair.first.possibleDatatypes) {
                                 if (argtype isAssignableTo possibleType) {
@@ -182,7 +184,7 @@ 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 in setOf(DataType.FLOAT, DataType.ARRAY_F)) {
+        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)
         }
         return noModifications
@@ -191,7 +193,7 @@ class TypecastsAdder(val program: Program, val errors: IErrorReporter) : AstWalk
     override fun after(memread: DirectMemoryRead, parent: Node): Iterable<IAstModification> {
         // make sure the memory address is an uword
         val dt = memread.addressExpression.inferType(program)
-        if(dt.isKnown && dt.typeOrElse(DataType.UWORD)!=DataType.UWORD) {
+        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))
@@ -202,7 +204,7 @@ class TypecastsAdder(val program: Program, val errors: IErrorReporter) : AstWalk
     override fun after(memwrite: DirectMemoryWrite, parent: Node): Iterable<IAstModification> {
         // make sure the memory address is an uword
         val dt = memwrite.addressExpression.inferType(program)
-        if(dt.isKnown && dt.typeOrElse(DataType.UWORD)!=DataType.UWORD) {
+        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))
@@ -214,10 +216,10 @@ class TypecastsAdder(val program: Program, val errors: IErrorReporter) : AstWalk
         // add a typecast to the return type if it doesn't match the subroutine's signature
         val returnValue = returnStmt.value
         if(returnValue!=null) {
-            val subroutine = returnStmt.definingSubroutine()!!
+            val subroutine = returnStmt.definingSubroutine!!
             if(subroutine.returntypes.size==1) {
                 val subReturnType = subroutine.returntypes.first()
-                if (returnValue.inferType(program).istype(subReturnType))
+                if (returnValue.inferType(program) istype subReturnType)
                     return noModifications
                 if (returnValue is NumericLiteralValue) {
                     val cast = returnValue.cast(subroutine.returntypes.single())

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

@@ -1,7 +1,7 @@
 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.FatalAstException
@@ -10,23 +10,23 @@ 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.IErrorReporter
 
 
 internal class VariousCleanups(val program: Program, val errors: IErrorReporter): AstWalker() {
 
     override fun before(nopStatement: NopStatement, parent: Node): Iterable<IAstModification> {
-        return listOf(IAstModification.Remove(nopStatement, parent as INameScope))
+        return listOf(IAstModification.Remove(nopStatement, parent as IStatementContainer))
     }
 
     override fun before(scope: AnonymousScope, parent: Node): Iterable<IAstModification> {
-        return if(parent is INameScope)
-            listOf(ScopeFlatten(scope, parent as INameScope))
+        return if(parent is IStatementContainer)
+            listOf(ScopeFlatten(scope, parent as IStatementContainer))
         else
             noModifications
     }
 
-    class ScopeFlatten(val scope: AnonymousScope, val into: INameScope) : IAstModification {
+    class ScopeFlatten(val scope: AnonymousScope, val into: IStatementContainer) : IAstModification {
         override fun perform() {
             val idx = into.statements.indexOf(scope)
             if(idx>=0) {
@@ -71,7 +71,7 @@ internal class VariousCleanups(val program: Program, val errors: IErrorReporter)
         }
 
         val sourceDt = typecast.expression.inferType(program)
-        if(sourceDt.istype(typecast.type))
+        if(sourceDt istype typecast.type)
             return listOf(IAstModification.ReplaceNode(typecast, typecast.expression, parent))
 
         return noModifications

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

@@ -8,21 +8,21 @@ import prog8.ast.expressions.FunctionCall
 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 {
 
     override fun visit(functionCall: FunctionCall) {
         val error = checkTypes(functionCall 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 {
@@ -44,7 +44,7 @@ class VerifyFunctionArgTypes(val program: Program) : IAstVisitor {
             val firstUnknownDt = argITypes.indexOfFirst { it.isUnknown }
             if(firstUnknownDt>=0)
                 return "argument ${firstUnknownDt+1} invalid argument type"
-            val argtypes = argITypes.map { it.typeOrElse(DataType.UNDEFINED) }
+            val argtypes = argITypes.map { it.getOr(DataType.UNDEFINED) }
             val target = call.target.targetStatement(program)
             if (target is Subroutine) {
                 if(call.args.size != target.parameters.size)

compiler/src/prog8/compiler/target/IAssemblyGenerator.kt

@@ -1,16 +0,0 @@
-package prog8.compiler.target
-
-import prog8.compiler.CompilationOptions
-
-internal interface IAssemblyGenerator {
-    fun compileToAssembly(): IAssemblyProgram
-}
-
-internal const val generatedLabelPrefix = "_prog8_label_"
-internal const val subroutineFloatEvalResultVar1 = "_prog8_float_eval_result1"
-internal const val subroutineFloatEvalResultVar2 = "_prog8_float_eval_result2"
-
-internal interface IAssemblyProgram {
-    val name: String
-    fun assemble(options: CompilationOptions)
-}

compiler/src/prog8/compiler/target/ICompilationTarget.kt

@@ -1,136 +0,0 @@
-package prog8.compiler.target
-
-import prog8.ast.IMemSizer
-import prog8.ast.IStringEncoding
-import prog8.ast.Program
-import prog8.ast.base.*
-import prog8.ast.expressions.IdentifierReference
-import prog8.ast.expressions.NumericLiteralValue
-import prog8.ast.statements.AssignTarget
-import prog8.compiler.CompilationOptions
-import prog8.compiler.IErrorReporter
-import prog8.compiler.Zeropage
-import prog8.compiler.target.c64.C64MachineDefinition
-import prog8.compiler.target.cbm.Petscii
-import prog8.compiler.target.cpu6502.codegen.AsmGen
-import prog8.compiler.target.cx16.CX16MachineDefinition
-import java.io.CharConversionException
-import java.nio.file.Path
-
-
-interface ICompilationTarget: IStringEncoding, IMemSizer {
-    val name: String
-    val machine: IMachineDefinition
-    override fun encodeString(str: String, altEncoding: Boolean): List<Short>
-    override fun decodeString(bytes: List<Short>, altEncoding: Boolean): String
-
-    fun isInRegularRAM(target: AssignTarget, program: Program): Boolean {
-        val memAddr = target.memoryAddress
-        val arrayIdx = target.arrayindexed
-        val ident = target.identifier
-        when {
-            memAddr != null -> {
-                return when (memAddr.addressExpression) {
-                    is NumericLiteralValue -> {
-                        machine.isRegularRAMaddress((memAddr.addressExpression as NumericLiteralValue).number.toInt())
-                    }
-                    is IdentifierReference -> {
-                        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 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 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 object C64Target: ICompilationTarget {
-    override val name = "c64"
-    override val machine = C64MachineDefinition
-    override fun encodeString(str: String, altEncoding: Boolean) =
-        try {
-            if (altEncoding) Petscii.encodeScreencode(str, true) else Petscii.encodePetscii(str, true)
-        } catch (x: CharConversionException) {
-            throw CharConversionException("can't convert string to target machine's char encoding: ${x.message}")
-        }
-    override fun decodeString(bytes: List<Short>, altEncoding: Boolean) =
-        try {
-            if (altEncoding) Petscii.decodeScreencode(bytes, true) else Petscii.decodePetscii(bytes, true)
-        } catch (x: CharConversionException) {
-            throw CharConversionException("can't decode string: ${x.message}")
-        }
-
-    override fun memorySize(dt: DataType): Int {
-        return when(dt) {
-            in ByteDatatypes -> 1
-            in WordDatatypes -> 2
-            DataType.FLOAT -> machine.FLOAT_MEM_SIZE
-            in PassByReferenceDatatypes -> machine.POINTER_MEM_SIZE
-            else -> -9999999
-        }
-    }
-}
-
-internal object Cx16Target: ICompilationTarget {
-    override val name = "cx16"
-    override val machine = CX16MachineDefinition
-    override fun encodeString(str: String, altEncoding: Boolean) =
-        try {
-            if (altEncoding) Petscii.encodeScreencode(str, true) else Petscii.encodePetscii(str, true)
-        } catch (x: CharConversionException) {
-            throw CharConversionException("can't convert string to target machine's char encoding: ${x.message}")
-        }
-    override fun decodeString(bytes: List<Short>, altEncoding: Boolean) =
-        try {
-            if (altEncoding) Petscii.decodeScreencode(bytes, true) else Petscii.decodePetscii(bytes, true)
-        } catch (x: CharConversionException) {
-            throw CharConversionException("can't decode string: ${x.message}")
-        }
-
-    override fun memorySize(dt: DataType): Int {
-        return when(dt) {
-            in ByteDatatypes -> 1
-            in WordDatatypes -> 2
-            DataType.FLOAT -> machine.FLOAT_MEM_SIZE
-            in PassByReferenceDatatypes -> machine.POINTER_MEM_SIZE
-            else -> -9999999
-        }
-    }
-}
-
-
-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)
-}