version 10.1

it no longer reuses the same temporary variable all the time.

todo

.github/FUNDING.yml

@@ -0,0 +1,13 @@
+# These are supported funding model platforms
+
+#github: # Replace with up to 4 GitHub Sponsors-enabled usernames e.g., [user1, user2]
+#patreon: # Replace with a single Patreon username
+open_collective: # Replace with a single Open Collective username
+ko_fi: irmen
+#tidelift: # Replace with a single Tidelift platform-name/package-name e.g., npm/babel
+#community_bridge: # Replace with a single Community Bridge project-name e.g., cloud-foundry
+#liberapay: # Replace with a single Liberapay username
+#issuehunt: # Replace with a single IssueHunt username
+#otechie: # Replace with a single Otechie username
+#lfx_crowdfunding: # Replace with a single LFX Crowdfunding project-name e.g., cloud-foundry
+#custom: # Replace with up to 4 custom sponsorship URLs e.g., ['link1', 'link2']

.idea/kotlinc.xml

@@ -4,6 +4,6 @@
     <option name="jvmTarget" value="11" />
   </component>
   <component name="KotlinJpsPluginSettings">
-    <option name="version" value="1.9.0-release-358" />
+    <option name="version" value="1.9.20" />
   </component>
 </project>

.idea/libraries/KotlinJavaRuntime.xml

@@ -1,19 +1,23 @@
 <component name="libraryTable">
-  <library name="KotlinJavaRuntime">
+  <library name="KotlinJavaRuntime" type="repository">
+    <properties maven-id="org.jetbrains.kotlin:kotlin-stdlib-jdk8:1.9.22" />
     <CLASSES>
-      <root url="jar://$KOTLIN_BUNDLED$/lib/kotlin-stdlib.jar!/" />
-      <root url="jar://$KOTLIN_BUNDLED$/lib/kotlin-reflect.jar!/" />
-      <root url="jar://$KOTLIN_BUNDLED$/lib/kotlin-test.jar!/" />
-      <root url="jar://$KOTLIN_BUNDLED$/lib/kotlin-stdlib-jdk7.jar!/" />
-      <root url="jar://$KOTLIN_BUNDLED$/lib/kotlin-stdlib-jdk8.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk8/1.9.22/kotlin-stdlib-jdk8-1.9.22.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/1.9.22/kotlin-stdlib-1.9.22.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-jdk7/1.9.22/kotlin-stdlib-jdk7-1.9.22.jar!/" />
     </CLASSES>
-    <JAVADOC />
+    <JAVADOC>
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk8/1.9.22/kotlin-stdlib-jdk8-1.9.22-javadoc.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/1.9.22/kotlin-stdlib-1.9.22-javadoc.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/annotations/13.0/annotations-13.0-javadoc.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk7/1.9.22/kotlin-stdlib-jdk7-1.9.22-javadoc.jar!/" />
+    </JAVADOC>
     <SOURCES>
-      <root url="jar://$KOTLIN_BUNDLED$/lib/kotlin-stdlib-sources.jar!/" />
-      <root url="jar://$KOTLIN_BUNDLED$/lib/kotlin-reflect-sources.jar!/" />
-      <root url="jar://$KOTLIN_BUNDLED$/lib/kotlin-test-sources.jar!/" />
-      <root url="jar://$KOTLIN_BUNDLED$/lib/kotlin-stdlib-jdk7-sources.jar!/" />
-      <root url="jar://$KOTLIN_BUNDLED$/lib/kotlin-stdlib-jdk8-sources.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk8/1.9.22/kotlin-stdlib-jdk8-1.9.22-sources.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/1.9.22/kotlin-stdlib-1.9.22-sources.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/annotations/13.0/annotations-13.0-sources.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk7/1.9.22/kotlin-stdlib-jdk7-1.9.22-sources.jar!/" />
     </SOURCES>
   </library>
 </component>

.idea/libraries/antlr_antlr4.xml

@@ -1,13 +1,13 @@
 <component name="libraryTable">
   <library name="antlr.antlr4" type="repository">
-    <properties maven-id="org.antlr:antlr4:4.13.0">
+    <properties maven-id="org.antlr:antlr4:4.13.1">
       <exclude>
         <dependency maven-id="com.ibm.icu:icu4j" />
       </exclude>
     </properties>
     <CLASSES>
-      <root url="jar://$MAVEN_REPOSITORY$/org/antlr/antlr4/4.13.0/antlr4-4.13.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/antlr/antlr4-runtime/4.13.0/antlr4-runtime-4.13.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/antlr/antlr4/4.13.1/antlr4-4.13.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/antlr/antlr4-runtime/4.13.1/antlr4-runtime-4.13.1.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/antlr/antlr-runtime/3.5.3/antlr-runtime-3.5.3.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/antlr/ST4/4.3.4/ST4-4.3.4.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/abego/treelayout/org.abego.treelayout.core/1.0.3/org.abego.treelayout.core-1.0.3.jar!/" />

.idea/libraries/io_kotest_assertions_core_jvm.xml

@@ -1,19 +1,19 @@
 <component name="libraryTable">
   <library name="io.kotest.assertions.core.jvm" type="repository">
-    <properties maven-id="io.kotest:kotest-assertions-core-jvm:5.6.2" />
+    <properties maven-id="io.kotest:kotest-assertions-core-jvm:5.8.0" />
     <CLASSES>
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-core-jvm/5.6.2/kotest-assertions-core-jvm-5.6.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-core-jvm/5.8.0/kotest-assertions-core-jvm-5.8.0.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk8/1.8.10/kotlin-stdlib-jdk8-1.8.10.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/1.8.10/kotlin-stdlib-1.8.10.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk7/1.8.10/kotlin-stdlib-jdk7-1.8.10.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-shared-jvm/5.6.2/kotest-assertions-shared-jvm-5.6.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-shared-jvm/5.8.0/kotest-assertions-shared-jvm-5.8.0.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/io/github/java-diff-utils/java-diff-utils/4.12/java-diff-utils-4.12.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/opentest4j/opentest4j/1.2.0/opentest4j-1.2.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/opentest4j/opentest4j/1.3.0/opentest4j-1.3.0.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-common/1.8.10/kotlin-stdlib-common-1.8.10.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-jdk8/1.7.0/kotlinx-coroutines-jdk8-1.7.0.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-reflect/1.8.10/kotlin-reflect-1.8.10.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-common-jvm/5.6.2/kotest-common-jvm-5.6.2.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-api-jvm/5.6.2/kotest-assertions-api-jvm-5.6.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-common-jvm/5.8.0/kotest-common-jvm-5.8.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-api-jvm/5.8.0/kotest-assertions-api-jvm-5.8.0.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-core-jvm/1.7.0/kotlinx-coroutines-core-jvm-1.7.0.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/annotations/23.0.0/annotations-23.0.0.jar!/" />
     </CLASSES>

.idea/libraries/io_kotest_property_jvm.xml

@@ -1,24 +0,0 @@
-<component name="libraryTable">
-  <library name="io.kotest.property.jvm" type="repository">
-    <properties maven-id="io.kotest:kotest-property-jvm:5.6.2" />
-    <CLASSES>
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-property-jvm/5.6.2/kotest-property-jvm-5.6.2.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/com/github/curious-odd-man/rgxgen/1.4/rgxgen-1.4.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk8/1.8.10/kotlin-stdlib-jdk8-1.8.10.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/1.8.10/kotlin-stdlib-1.8.10.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk7/1.8.10/kotlin-stdlib-jdk7-1.8.10.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-common-jvm/5.6.2/kotest-common-jvm-5.6.2.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-shared-jvm/5.6.2/kotest-assertions-shared-jvm-5.6.2.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-api-jvm/5.6.2/kotest-assertions-api-jvm-5.6.2.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-jdk8/1.7.0/kotlinx-coroutines-jdk8-1.7.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/opentest4j/opentest4j/1.2.0/opentest4j-1.2.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-common/1.8.10/kotlin-stdlib-common-1.8.10.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/github/java-diff-utils/java-diff-utils/4.12/java-diff-utils-4.12.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-reflect/1.8.10/kotlin-reflect-1.8.10.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-core-jvm/1.7.0/kotlinx-coroutines-core-jvm-1.7.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/annotations/23.0.0/annotations-23.0.0.jar!/" />
-    </CLASSES>
-    <JAVADOC />
-    <SOURCES />
-  </library>
-</component>

.idea/libraries/io_kotest_runner_junit5_jvm.xml

@@ -1,29 +1,29 @@
 <component name="libraryTable">
   <library name="io.kotest.runner.junit5.jvm" type="repository">
-    <properties maven-id="io.kotest:kotest-runner-junit5-jvm:5.6.2" />
+    <properties maven-id="io.kotest:kotest-runner-junit5-jvm:5.8.0" />
     <CLASSES>
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-runner-junit5-jvm/5.6.2/kotest-runner-junit5-jvm-5.6.2.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-framework-api-jvm/5.6.2/kotest-framework-api-jvm-5.6.2.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-shared-jvm/5.6.2/kotest-assertions-shared-jvm-5.6.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-runner-junit5-jvm/5.8.0/kotest-runner-junit5-jvm-5.8.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-framework-api-jvm/5.8.0/kotest-framework-api-jvm-5.8.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-shared-jvm/5.8.0/kotest-assertions-shared-jvm-5.8.0.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/io/github/java-diff-utils/java-diff-utils/4.12/java-diff-utils-4.12.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-test-jvm/1.7.0/kotlinx-coroutines-test-jvm-1.7.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-common-jvm/5.6.2/kotest-common-jvm-5.6.2.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-framework-engine-jvm/5.6.2/kotest-framework-engine-jvm-5.6.2.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/github/classgraph/classgraph/4.8.157/classgraph-4.8.157.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-common-jvm/5.8.0/kotest-common-jvm-5.8.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-framework-engine-jvm/5.8.0/kotest-framework-engine-jvm-5.8.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/github/classgraph/classgraph/4.8.162/classgraph-4.8.162.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/com/github/ajalt/mordant/1.2.1/mordant-1.2.1.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/com/github/ajalt/colormath/1.2.0/colormath-1.2.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/opentest4j/opentest4j/1.2.0/opentest4j-1.2.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/opentest4j/opentest4j/1.3.0/opentest4j-1.3.0.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-debug/1.7.0/kotlinx-coroutines-debug-1.7.0.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/net/java/dev/jna/jna/5.9.0/jna-5.9.0.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/net/java/dev/jna/jna-platform/5.9.0/jna-platform-5.9.0.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/net/bytebuddy/byte-buddy/1.10.9/byte-buddy-1.10.9.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/net/bytebuddy/byte-buddy-agent/1.10.9/byte-buddy-agent-1.10.9.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-framework-discovery-jvm/5.6.2/kotest-framework-discovery-jvm-5.6.2.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-core-jvm/5.6.2/kotest-assertions-core-jvm-5.6.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-framework-discovery-jvm/5.8.0/kotest-framework-discovery-jvm-5.8.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-core-jvm/5.8.0/kotest-assertions-core-jvm-5.8.0.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-jdk8/1.7.0/kotlinx-coroutines-jdk8-1.7.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-api-jvm/5.6.2/kotest-assertions-api-jvm-5.6.2.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-extensions-jvm/5.6.2/kotest-extensions-jvm-5.6.2.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-framework-concurrency-jvm/5.6.2/kotest-framework-concurrency-jvm-5.6.2.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-api-jvm/5.8.0/kotest-assertions-api-jvm-5.8.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-extensions-jvm/5.8.0/kotest-extensions-jvm-5.8.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-framework-concurrency-jvm/5.8.0/kotest-framework-concurrency-jvm-5.8.0.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-core-jvm/1.7.0/kotlinx-coroutines-core-jvm-1.7.0.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/annotations/23.0.0/annotations-23.0.0.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/junit/platform/junit-platform-engine/1.8.2/junit-platform-engine-1.8.2.jar!/" />

.idea/libraries/jetbrains_kotlinx_cli_jvm.xml

@@ -1,8 +1,8 @@
 <component name="libraryTable">
   <library name="jetbrains.kotlinx.cli.jvm" type="repository">
-    <properties include-transitive-deps="false" maven-id="org.jetbrains.kotlinx:kotlinx-cli-jvm:0.3.5" />
+    <properties include-transitive-deps="false" maven-id="org.jetbrains.kotlinx:kotlinx-cli-jvm:0.3.6" />
     <CLASSES>
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-cli-jvm/0.3.5/kotlinx-cli-jvm-0.3.5.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-cli-jvm/0.3.6/kotlinx-cli-jvm-0.3.6.jar!/" />
     </CLASSES>
     <JAVADOC />
     <SOURCES />

.idea/libraries/slf4j_simple.xml

@@ -1,9 +1,9 @@
 <component name="libraryTable">
   <library name="slf4j.simple" type="repository">
-    <properties maven-id="org.slf4j:slf4j-simple:2.0.7" />
+    <properties maven-id="org.slf4j:slf4j-simple:2.0.11" />
     <CLASSES>
-      <root url="jar://$MAVEN_REPOSITORY$/org/slf4j/slf4j-simple/2.0.7/slf4j-simple-2.0.7.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/slf4j/slf4j-api/2.0.7/slf4j-api-2.0.7.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/slf4j/slf4j-simple/2.0.11/slf4j-simple-2.0.11.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/slf4j/slf4j-api/2.0.11/slf4j-api-2.0.11.jar!/" />
     </CLASSES>
     <JAVADOC />
     <SOURCES />

.idea/misc.xml

@@ -16,6 +16,9 @@
       </list>
     </option>
   </component>
+  <component name="Black">
+    <option name="sdkName" value="Python 3.11" />
+  </component>
   <component name="FrameworkDetectionExcludesConfiguration">
     <type id="Python" />
   </component>

README.md

@@ -1,3 +1,4 @@
+[![ko-fi](https://ko-fi.com/img/githubbutton_sm.svg)](https://ko-fi.com/H2H6S0FFF)
 [![Documentation](https://readthedocs.org/projects/prog8/badge/?version=latest)](https://prog8.readthedocs.io/)
 
 Prog8 - Structured Programming Language for 8-bit 6502/65c02 microprocessors
@@ -9,6 +10,13 @@ This is a structured programming language for the 8-bit 6502/6510/65c02 micropro
 as used in many home computers from that era. It is a medium to low level programming language,
 which aims to provide many conveniences over raw assembly code (even when using a macro assembler).
 
+**Want to buy me a coffee or a pizza perhaps?**
+
+This project was created over the last couple of years by dedicating thousands of hours of my free time to it, to make it the best I possibly can.
+If you like Prog8, and think it's worth a nice cup of hot coffee or a delicious pizza, 
+you can help me out a little bit over at [ko-fi.com/irmen](https://ko-fi.com/irmen). 
+
+
 Documentation
 -------------
 Full documentation (syntax reference, how to use the language and the compiler, etc.) can be found at:
@@ -74,6 +82,8 @@ What does Prog8 provide?
 - "c64": Commodore-64  (6502 like CPU)
 - "c128": Commodore-128  (6502 like CPU - the Z80 cpu mode is not supported)
 - "cx16": [CommanderX16](https://www.commanderx16.com)  (65c02 CPU)
+- "pet32": Commodore PET (experimental)
+- "atari": Atari 8 bit such as 800XL (experimental)
 - If you only use standard kernal and prog8 library routines, it is possible to compile the *exact same program* for different machines (just change the compiler target flag)
 
 

codeCore/build.gradle

@@ -32,10 +32,10 @@ dependencies {
 sourceSets {
     main {
         java {
-            srcDirs = ["${project.projectDir}/src"]
+            srcDir "${project.projectDir}/src"
         }
         resources {
-            srcDirs = ["${project.projectDir}/res"]
+            srcDir "${project.projectDir}/res"
         }
     }
 }

codeCore/src/prog8/code/SymbolTable.kt

@@ -196,13 +196,10 @@ class StStaticVariable(name: String,
         }
         if(onetimeInitializationNumericValue!=null) {
             require(dt in NumericDatatypes)
-            require(onetimeInitializationNumericValue!=0.0) { "zero as init value should just remain uninitialized"}
         }
         if(onetimeInitializationArrayValue!=null) {
             require(dt in ArrayDatatypes)
-            if(onetimeInitializationArrayValue.all { it.number!=null} ) {
-                require(onetimeInitializationArrayValue.any { it.number != 0.0 }) { "array of all zerors as init value should just remain uninitialized" }
-            }
+            require(length==onetimeInitializationArrayValue.size)
         }
         if(onetimeInitializationStringValue!=null) {
             require(dt == DataType.STR)
@@ -213,8 +210,7 @@ class StStaticVariable(name: String,
 
 
 class StConstant(name: String, val dt: DataType, val value: Double, astNode: PtNode) :
-    StNode(name, StNodeType.CONSTANT, astNode) {
-}
+    StNode(name, StNodeType.CONSTANT, astNode)
 
 
 class StMemVar(name: String,
@@ -236,12 +232,11 @@ class StMemorySlab(
     val align: UInt,
     astNode: PtNode
 ):
-    StNode(name, StNodeType.MEMORYSLAB, astNode) {
-}
+    StNode(name, StNodeType.MEMORYSLAB, astNode)
+
 
 class StSub(name: String, val parameters: List<StSubroutineParameter>, val returnType: DataType?, astNode: PtNode) :
-        StNode(name, StNodeType.SUBROUTINE, astNode) {
-}
+        StNode(name, StNodeType.SUBROUTINE, astNode)
 
 
 class StRomSub(name: String,

codeCore/src/prog8/code/SymbolTableMaker.kt

@@ -26,8 +26,6 @@ class SymbolTableMaker(private val program: PtProgram, private val options: Comp
                 PtMemMapped("P8ZP_SCRATCH_REG", DataType.UBYTE, options.compTarget.machine.zeropage.SCRATCH_REG, null, Position.DUMMY),
                 PtMemMapped("P8ZP_SCRATCH_W1", DataType.UWORD, options.compTarget.machine.zeropage.SCRATCH_W1, null, Position.DUMMY),
                 PtMemMapped("P8ZP_SCRATCH_W2", DataType.UWORD, options.compTarget.machine.zeropage.SCRATCH_W2, null, Position.DUMMY),
-                PtMemMapped("P8ESTACK_LO", DataType.ARRAY_UB, options.compTarget.machine.ESTACK_LO, 128u, Position.DUMMY),
-                PtMemMapped("P8ESTACK_HI", DataType.ARRAY_UB, options.compTarget.machine.ESTACK_HI, 128u, Position.DUMMY)
             ).forEach {
                 it.parent = program
                 st.add(StMemVar(it.name, it.type, it.address, it.arraySize?.toInt(), it))
@@ -76,10 +74,9 @@ class SymbolTableMaker(private val program: PtProgram, private val options: Comp
                             numElements = value.value.length + 1   // include the terminating 0-byte
                         }
                         is PtArray -> {
-                            val array = makeInitialArray(value)
-                            initialArray = if(array.all { it.number==0.0 }) null else array            // all 0 as init value -> just uninitialized
+                            initialArray = makeInitialArray(value)
                             initialString = null
-                            numElements = array.size
+                            numElements = initialArray.size
                             require(node.arraySize?.toInt()==numElements)
                         }
                         else -> {
@@ -128,7 +125,11 @@ class SymbolTableMaker(private val program: PtProgram, private val options: Comp
     private fun makeInitialArray(value: PtArray): List<StArrayElement> {
         return value.children.map {
             when(it) {
-                is PtAddressOf -> StArrayElement(null, it.identifier.name)
+                is PtAddressOf -> {
+                    if(it.isFromArrayElement)
+                        TODO("address-of array element $it in initial array value")
+                    StArrayElement(null, it.identifier.name)
+                }
                 is PtIdentifier -> StArrayElement(null, it.name)
                 is PtNumber -> StArrayElement(it.number, null)
                 else -> throw AssemblyError("invalid array element $it")
@@ -173,7 +174,7 @@ class SymbolTableMaker(private val program: PtProgram, private val options: Comp
 //                }
 //                VarDeclType.MEMORY -> {
 //                    val numElements =
-//                        if(decl.datatype in ArrayDatatypes)
+//                        if(decl.isArray)
 //                            decl.arraysize!!.constIndex()
 //                        else null
 //                    val astNode = PtVariable(decl.name, decl.datatype, null, null, decl.position)

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

@@ -31,7 +31,10 @@ sealed class PtNode(val position: Position) {
 }
 
 
-class PtNodeGroup : PtNode(Position.DUMMY)
+sealed interface IPtStatementContainer
+
+
+class PtNodeGroup : PtNode(Position.DUMMY), IPtStatementContainer
 
 
 sealed class PtNamedNode(var name: String, position: Position): PtNode(position) {
@@ -64,26 +67,30 @@ class PtProgram(
         children.asSequence().filterIsInstance<PtBlock>()
 
     fun entrypoint(): PtSub? =
-        allBlocks().firstOrNull { it.name == "main" || it.name=="p8_main" }
+        allBlocks().firstOrNull { it.name == "main" || it.name=="p8b_main" }
             ?.children
-            ?.firstOrNull { it is PtSub && (it.name == "start" || it.name=="main.start" || it.name=="p8_start" || it.name=="p8_main.p8_start") } as PtSub?
+            ?.firstOrNull { it is PtSub && (it.name == "start" || it.name=="main.start" || it.name=="p8s_start" || it.name=="p8b_main.p8s_start") } as PtSub?
 }
 
 
 class PtBlock(name: String,
-              val address: UInt?,
               val library: Boolean,
-              val forceOutput: Boolean,
-              val noSymbolPrefixing: Boolean,
-              val alignment: BlockAlignment,
               val source: SourceCode,       // taken from the module the block is defined in.
+              val options: Options,
               position: Position
-) : PtNamedNode(name, position) {
+) : PtNamedNode(name, position), IPtStatementContainer {
     enum class BlockAlignment {
         NONE,
         WORD,
         PAGE
     }
+
+    class Options(val address: UInt? = null,
+                  val forceOutput: Boolean = false,
+                  val noSymbolPrefixing: Boolean = false,
+                  val veraFxMuls: Boolean = false,
+                  val ignoreUnused: Boolean = false,
+                  val alignment: BlockAlignment = BlockAlignment.NONE)
 }
 
 

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

@@ -3,7 +3,7 @@ package prog8.code.ast
 import prog8.code.core.*
 import java.util.*
 import kotlin.math.abs
-import kotlin.math.round
+import kotlin.math.truncate
 
 
 sealed class PtExpression(val type: DataType, position: Position) : PtNode(position) {
@@ -24,9 +24,26 @@ sealed class PtExpression(val type: DataType, position: Position) : PtNode(posit
 
     infix fun isSameAs(other: PtExpression): Boolean {
         return when(this) {
-            is PtAddressOf -> other is PtAddressOf && other.type==type && other.identifier isSameAs identifier
+            is PtAddressOf -> {
+                if(other !is PtAddressOf)
+                    return false
+                if (other.type!==type || !(other.identifier isSameAs identifier))
+                    return false
+                if(other.children.size!=children.size)
+                    return false
+                if(children.size==1)
+                    return true
+                return arrayIndexExpr!! isSameAs other.arrayIndexExpr!!
+            }
             is PtArrayIndexer -> other is PtArrayIndexer && other.type==type && other.variable isSameAs variable && other.index isSameAs index && other.splitWords==splitWords
-            is PtBinaryExpression -> other is PtBinaryExpression && other.left isSameAs left && other.right isSameAs right
+            is PtBinaryExpression -> {
+                if(other !is PtBinaryExpression || other.operator!=operator)
+                    false
+                else if(operator in AssociativeOperators)
+                    (other.left isSameAs left && other.right isSameAs right) || (other.left isSameAs right && other.right isSameAs left)
+                else
+                    other.left isSameAs left && other.right isSameAs right
+            }
             is PtContainmentCheck -> other is PtContainmentCheck && other.type==type && other.element isSameAs element && other.iterable isSameAs iterable
             is PtIdentifier -> other is PtIdentifier && other.type==type && other.name==name
             is PtMachineRegister -> other is PtMachineRegister && other.type==type && other.register==register
@@ -62,7 +79,12 @@ sealed class PtExpression(val type: DataType, position: Position) : PtNode(posit
             is PtArray -> true
             is PtArrayIndexer -> index is PtNumber || index is PtIdentifier
             is PtBinaryExpression -> false
-            is PtBuiltinFunctionCall -> name in arrayOf("msb", "lsb", "peek", "peekw", "mkword", "set_carry", "set_irqd", "clear_carry", "clear_irqd")
+            is PtBuiltinFunctionCall -> {
+                when (name) {
+                    in arrayOf("msb", "lsb", "mkword", "set_carry", "set_irqd", "clear_carry", "clear_irqd") -> this.args.all { it.isSimple() }
+                    else -> false
+                }
+            }
             is PtContainmentCheck -> false
             is PtFunctionCall -> false
             is PtIdentifier -> true
@@ -105,13 +127,21 @@ sealed class PtExpression(val type: DataType, position: Position) : PtNode(posit
 
 class PtAddressOf(position: Position) : PtExpression(DataType.UWORD, position) {
     val identifier: PtIdentifier
-        get() = children.single() as PtIdentifier
+        get() = children[0] as PtIdentifier
+    val arrayIndexExpr: PtExpression?
+        get() = if(children.size==2) children[1] as PtExpression else null
+
+    val isFromArrayElement: Boolean
+        get() = children.size==2
 }
 
 
 class PtArrayIndexer(elementType: DataType, position: Position): PtExpression(elementType, position) {
     val variable: PtIdentifier
-        get() = children[0] as PtIdentifier
+        get() {
+            require((children[0] as? PtIdentifier)?.type in ArrayDatatypes+DataType.STR)        // TODO remove
+            return children[0] as PtIdentifier
+        }
     val index: PtExpression
         get() = children[1] as PtExpression
 
@@ -209,9 +239,9 @@ class PtNumber(type: DataType, val number: Double, position: Position) : PtExpre
         if(type==DataType.BOOL)
             throw IllegalArgumentException("bool should have become ubyte @$position")
         if(type!=DataType.FLOAT) {
-            val rounded = round(number)
-            if (rounded != number)
-                throw IllegalArgumentException("refused rounding of float to avoid loss of precision @$position")
+            val trunc = truncate(number)
+            if (trunc != number)
+                throw IllegalArgumentException("refused truncating of float to avoid loss of precision @$position")
         }
     }
 
@@ -220,7 +250,10 @@ class PtNumber(type: DataType, val number: Double, position: Position) : PtExpre
     override fun equals(other: Any?): Boolean {
         if(other==null || other !is PtNumber)
             return false
-        return number==other.number
+        else if(type!=DataType.BOOL && other.type!=DataType.BOOL)
+            return number==other.number
+        else
+            return type==other.type && number==other.number
     }
 
     operator fun compareTo(other: PtNumber): Int = number.compareTo(other.number)

codeCore/src/prog8/code/ast/AstPrinter.kt

@@ -53,15 +53,24 @@ fun printAst(root: PtNode, skipLibraries: Boolean, output: (text: String) -> Uni
                     "goto ${node.identifier.name}"
                 else if(node.address!=null)
                     "goto ${node.address.toHex()}"
-                else if(node.generatedLabel!=null)
-                    "goto ${node.generatedLabel}"
                 else
                     "???"
             }
             is PtAsmSub -> {
-                val params = if (node.parameters.isEmpty()) "" else "...TODO ${node.parameters.size} PARAMS..."
+                val params = node.parameters.map {
+                                val register = it.first.registerOrPair
+                                val statusflag = it.first.statusflag
+                                "${it.second.type} ${it.second.name} @${register ?: statusflag}"
+                            }.joinToString(", ")
                 val clobbers = if (node.clobbers.isEmpty()) "" else "clobbers ${node.clobbers}"
-                val returns = if (node.returns.isEmpty()) "" else (if (node.returns.size == 1) "-> ${node.returns[0].second.name.lowercase()}" else "-> ${node.returns.map { it.second.name.lowercase() }}")
+                val returns = if (node.returns.isEmpty()) "" else {
+                    "-> ${node.returns.map {
+                        val register = it.first.registerOrPair
+                        val statusflag = it.first.statusflag
+                        "${it.second} @${register ?: statusflag}"}
+                        .joinToString(", ")
+                    }"
+                }
                 val str = if (node.inline) "inline " else ""
                 if(node.address==null) {
                     str + "asmsub ${node.name}($params) $clobbers $returns"
@@ -70,8 +79,8 @@ fun printAst(root: PtNode, skipLibraries: Boolean, output: (text: String) -> Uni
                 }
             }
             is PtBlock -> {
-                val addr = if(node.address==null) "" else "@${node.address.toHex()}"
-                val align = if(node.alignment==PtBlock.BlockAlignment.NONE) "" else "align=${node.alignment}"
+                val addr = if(node.options.address==null) "" else "@${node.options.address.toHex()}"
+                val align = if(node.options.alignment==PtBlock.BlockAlignment.NONE) "" else "align=${node.options.alignment}"
                 "\nblock '${node.name}' $addr $align"
             }
             is PtConstant -> {
@@ -89,7 +98,7 @@ fun printAst(root: PtNode, skipLibraries: Boolean, output: (text: String) -> Uni
                 }
             }
             is PtSub -> {
-                val params = if (node.parameters.isEmpty()) "" else "...TODO ${node.parameters.size} PARAMS..."
+                val params = node.parameters.map { "${it.type} ${it.name}" }.joinToString(", ")
                 var str = "sub ${node.name}($params) "
                 if(node.returntype!=null)
                     str += "-> ${node.returntype.name.lowercase()}"
@@ -126,7 +135,6 @@ fun printAst(root: PtNode, skipLibraries: Boolean, output: (text: String) -> Uni
                 else
                     "->"
             }
-            else -> throw InternalCompilerException("unrecognised ast node $node")
         }
     }
 

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

@@ -23,7 +23,7 @@ class PtSub(
     val parameters: List<PtSubroutineParameter>,
     val returntype: DataType?,
     position: Position
-) : PtNamedNode(name, position), IPtSubroutine {
+) : PtNamedNode(name, position), IPtSubroutine, IPtStatementContainer {
     init {
         // params and return value should not be str
         if(parameters.any{ it.type !in NumericDatatypes })
@@ -101,9 +101,8 @@ class PtIfElse(position: Position) : PtNode(position) {
 }
 
 
-class PtJump(val identifier: PtIdentifier?,
+class PtJump(val identifier: PtIdentifier?,     // note: even ad-hoc labels are wrapped as an Identifier to simplify code. Just use dummy type and position.
              val address: UInt?,
-             val generatedLabel: String?,
              position: Position) : PtNode(position) {
     init {
         identifier?.let {it.parent = this }

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

@@ -70,6 +70,8 @@ class FSignature(val pure: Boolean,      // does it have side effects?
 
 val BuiltinFunctions: Map<String, FSignature> = mapOf(
     // this set of function have no return value and operate in-place:
+    "setlsb"    to FSignature(false, listOf(FParam("variable", arrayOf(DataType.WORD, DataType.UWORD)), FParam("value", arrayOf(DataType.BYTE, DataType.UBYTE))), null),
+    "setmsb"    to FSignature(false, listOf(FParam("variable", arrayOf(DataType.WORD, DataType.UWORD)), FParam("value", arrayOf(DataType.BYTE, DataType.UBYTE))), null),
     "rol"       to FSignature(false, listOf(FParam("item", arrayOf(DataType.UBYTE, DataType.UWORD))), null),
     "ror"       to FSignature(false, listOf(FParam("item", arrayOf(DataType.UBYTE, DataType.UWORD))), null),
     "rol2"      to FSignature(false, listOf(FParam("item", arrayOf(DataType.UBYTE, DataType.UWORD))), null),
@@ -78,7 +80,9 @@ val BuiltinFunctions: Map<String, FSignature> = mapOf(
     "reverse"   to FSignature(false, listOf(FParam("array", ArrayDatatypes)), null),
     // cmp returns a status in the carry flag, but not a proper return value
     "cmp"       to FSignature(false, listOf(FParam("value1", IntegerDatatypesNoBool), FParam("value2", NumericDatatypesNoBool)), null),
-    "prog8_lib_stringcompare"       to FSignature(true, listOf(FParam("str1", arrayOf(DataType.STR)), FParam("str2", arrayOf(DataType.STR))), DataType.BYTE),
+    "prog8_lib_stringcompare"     to FSignature(true, listOf(FParam("str1", arrayOf(DataType.STR)), FParam("str2", arrayOf(DataType.STR))), DataType.BYTE),
+    "prog8_lib_square_byte"       to FSignature(true, listOf(FParam("value", arrayOf(DataType.BYTE, DataType.UBYTE))), DataType.UBYTE),
+    "prog8_lib_square_word"       to FSignature(true, listOf(FParam("value", arrayOf(DataType.WORD, DataType.UWORD))), DataType.UWORD),
     "abs"       to FSignature(true, listOf(FParam("value", NumericDatatypesNoBool)), null),
     "abs__byte"  to FSignature(true, listOf(FParam("value", arrayOf(DataType.BYTE))), DataType.BYTE),
     "abs__word"  to FSignature(true, listOf(FParam("value", arrayOf(DataType.WORD))), DataType.WORD),
@@ -116,19 +120,16 @@ val BuiltinFunctions: Map<String, FSignature> = mapOf(
     "max__uword" to FSignature(true, listOf(FParam("val1", arrayOf(DataType.UWORD)), FParam("val2", arrayOf(DataType.UWORD))), DataType.UWORD),
     "peek"      to FSignature(true, listOf(FParam("address", arrayOf(DataType.UWORD))), DataType.UBYTE),
     "peekw"     to FSignature(true, listOf(FParam("address", arrayOf(DataType.UWORD))), DataType.UWORD),
+    "peekf"     to FSignature(true, listOf(FParam("address", arrayOf(DataType.UWORD))), DataType.FLOAT),
     "poke"      to FSignature(false, listOf(FParam("address", arrayOf(DataType.UWORD)), FParam("value", arrayOf(DataType.UBYTE))), null),
-    "pokemon"   to FSignature(false, listOf(FParam("address", arrayOf(DataType.UWORD)), FParam("value", arrayOf(DataType.UBYTE))), null),
     "pokew"     to FSignature(false, listOf(FParam("address", arrayOf(DataType.UWORD)), FParam("value", arrayOf(DataType.UWORD))), null),
-    "pop"       to FSignature(false, listOf(FParam("target", ByteDatatypes)), null),
-    "popw"      to FSignature(false, listOf(FParam("target", WordDatatypes)), null),
-    "push"      to FSignature(false, listOf(FParam("value", ByteDatatypes)), null),
-    "pushw"     to FSignature(false, listOf(FParam("value", WordDatatypes)), null),
+    "pokef"     to FSignature(false, listOf(FParam("address", arrayOf(DataType.UWORD)), FParam("value", arrayOf(DataType.FLOAT))), null),
+    "pokemon"   to FSignature(false, listOf(FParam("address", arrayOf(DataType.UWORD)), FParam("value", arrayOf(DataType.UBYTE))), DataType.UBYTE),
     "rsave"     to FSignature(false, emptyList(), null),
-    "rsavex"    to FSignature(false, emptyList(), null),
     "rrestore"  to FSignature(false, emptyList(), null),
-    "rrestorex" to FSignature(false, emptyList(), null),
     "memory"    to FSignature(true, listOf(FParam("name", arrayOf(DataType.STR)), FParam("size", arrayOf(DataType.UWORD)), FParam("alignment", arrayOf(DataType.UWORD))), DataType.UWORD),
     "callfar"   to FSignature(false, listOf(FParam("bank", arrayOf(DataType.UBYTE)), FParam("address", arrayOf(DataType.UWORD)), FParam("arg", arrayOf(DataType.UWORD))), DataType.UWORD),
+    "call"      to FSignature(false, listOf(FParam("address", arrayOf(DataType.UWORD))), DataType.UWORD),
 )
 
-val InplaceModifyingBuiltinFunctions = setOf("rol", "ror", "rol2", "ror2", "sort", "reverse")
+val InplaceModifyingBuiltinFunctions = setOf("setlsb", "setmsb", "rol", "ror", "rol2", "ror2", "sort", "reverse")

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

@@ -8,24 +8,32 @@ class CompilationOptions(val output: OutputType,
                          val launcher: CbmPrgLauncherType,
                          val zeropage: ZeropageType,
                          val zpReserved: List<UIntRange>,
+                         val zpAllowed: List<UIntRange>,
                          val floats: Boolean,
                          val noSysInit: Boolean,
                          val compTarget: ICompilationTarget,
                          // these are set later, based on command line arguments or options in the source code:
                          var loadAddress: UInt,
-                         var slowCodegenWarnings: Boolean = false,
+                         var warnSymbolShadowing: Boolean = false,
                          var optimize: Boolean = false,
-                         var optimizeFloatExpressions: Boolean = false,
                          var asmQuiet: Boolean = false,
                          var asmListfile: Boolean = false,
+                         var includeSourcelines: Boolean = false,
                          var experimentalCodegen: Boolean = false,
                          var varsHighBank: Int? = null,
+                         var varsGolden: Boolean = false,
+                         var slabsHighBank: Int? = null,
+                         var slabsGolden: Boolean = false,
                          var splitWordArrays: Boolean = false,
-                         var evalStackBaseAddress: UInt? = null,
+                         var breakpointCpuInstruction: String? = null,
                          var outputDir: Path = Path(""),
                          var symbolDefs: Map<String, String> = emptyMap()
 ) {
     init {
         compTarget.machine.initializeMemoryAreas(this)
     }
+
+    companion object {
+        val AllZeropageAllowed: List<UIntRange> = listOf(0u..255u)
+    }
 }

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

@@ -1,12 +1,13 @@
 package prog8.code.core
 
 enum class DataType {
-    UBYTE,              // pass by value
-    BYTE,               // pass by value
-    UWORD,              // pass by value
-    WORD,               // pass by value
-    FLOAT,              // pass by value
-    BOOL,               // pass by value
+    UBYTE,              // pass by value            8 bits unsigned
+    BYTE,               // pass by value            8 bits signed
+    UWORD,              // pass by value            16 bits unsigned
+    WORD,               // pass by value            16 bits signed
+    LONG,               // pass by value            32 bits signed
+    FLOAT,              // pass by value            machine dependent
+    BOOL,               // pass by value            bit 0 of a 8 bit byte
     STR,                // pass by reference
     ARRAY_UB,           // pass by reference
     ARRAY_B,            // pass by reference
@@ -23,11 +24,12 @@ enum class DataType {
      */
     infix fun isAssignableTo(targetType: DataType) =
         when(this) {
-            BOOL -> targetType.oneOf(BOOL, BYTE, UBYTE, WORD, UWORD, FLOAT)
-            UBYTE -> targetType.oneOf(UBYTE, WORD, UWORD, FLOAT, BOOL)
-            BYTE -> targetType.oneOf(BYTE, WORD, FLOAT)
-            UWORD -> targetType.oneOf(UWORD, FLOAT)
-            WORD -> targetType.oneOf(WORD, FLOAT)
+            BOOL -> targetType.oneOf(BOOL, BYTE, UBYTE, WORD, UWORD, LONG, FLOAT)
+            UBYTE -> targetType.oneOf(UBYTE, WORD, UWORD, LONG, FLOAT, BOOL)
+            BYTE -> targetType.oneOf(BYTE, WORD, LONG, FLOAT)
+            UWORD -> targetType.oneOf(UWORD, LONG, FLOAT)
+            WORD -> targetType.oneOf(WORD, LONG, FLOAT)
+            LONG -> targetType.oneOf(LONG, FLOAT)
             FLOAT -> targetType.oneOf(FLOAT)
             STR -> targetType.oneOf(STR, UWORD)
             in ArrayDatatypes -> targetType == this
@@ -41,7 +43,8 @@ enum class DataType {
             this == other -> false
             this in ByteDatatypes -> false
             this in WordDatatypes -> other in ByteDatatypes
-            this== STR && other== UWORD || this== UWORD && other== STR -> false
+            this == LONG -> other in ByteDatatypes+WordDatatypes
+            this == STR && other == UWORD || this == UWORD && other == STR -> false
             else -> true
         }
 
@@ -76,6 +79,13 @@ enum class RegisterOrPair {
 
     companion object {
         val names by lazy { values().map { it.toString()} }
+        fun fromCpuRegister(cpu: CpuRegister): RegisterOrPair {
+            return when(cpu) {
+                CpuRegister.A -> A
+                CpuRegister.X -> X
+                CpuRegister.Y -> Y
+            }
+        }
     }
 
     fun asCpuRegister(): CpuRegister = when(this) {
@@ -110,17 +120,17 @@ enum class BranchCondition {
     PL,     // PL == POS
     POS,
     VS,
-    VC,
+    VC
 }
 
 
 val ByteDatatypes = arrayOf(DataType.UBYTE, DataType.BYTE, DataType.BOOL)
 val WordDatatypes = arrayOf(DataType.UWORD, DataType.WORD)
-val IntegerDatatypes = arrayOf(DataType.UBYTE, DataType.BYTE, DataType.UWORD, DataType.WORD, DataType.BOOL)
-val IntegerDatatypesNoBool = arrayOf(DataType.UBYTE, DataType.BYTE, DataType.UWORD, DataType.WORD)
-val NumericDatatypes = arrayOf(DataType.UBYTE, DataType.BYTE, DataType.UWORD, DataType.WORD, DataType.FLOAT, DataType.BOOL)
-val NumericDatatypesNoBool = arrayOf(DataType.UBYTE, DataType.BYTE, DataType.UWORD, DataType.WORD, DataType.FLOAT)
-val SignedDatatypes =  arrayOf(DataType.BYTE, DataType.WORD, DataType.FLOAT)
+val IntegerDatatypesNoBool = arrayOf(DataType.UBYTE, DataType.BYTE, DataType.UWORD, DataType.WORD, DataType.LONG)
+val IntegerDatatypes = IntegerDatatypesNoBool + DataType.BOOL
+val NumericDatatypesNoBool = arrayOf(DataType.UBYTE, DataType.BYTE, DataType.UWORD, DataType.WORD, DataType.LONG, DataType.FLOAT)
+val NumericDatatypes = NumericDatatypesNoBool + DataType.BOOL
+val SignedDatatypes =  arrayOf(DataType.BYTE, DataType.WORD, DataType.LONG, DataType.FLOAT)
 val ArrayDatatypes = arrayOf(DataType.ARRAY_UB, DataType.ARRAY_B, DataType.ARRAY_UW, DataType.ARRAY_UW_SPLIT, DataType.ARRAY_W, DataType.ARRAY_W_SPLIT, DataType.ARRAY_F, DataType.ARRAY_BOOL)
 val StringlyDatatypes = arrayOf(DataType.STR, DataType.ARRAY_UB, DataType.ARRAY_B, DataType.UWORD)
 val SplitWordArrayTypes = arrayOf(DataType.ARRAY_UW_SPLIT, DataType.ARRAY_W_SPLIT)
@@ -150,8 +160,10 @@ val ElementToArrayTypes = mapOf(
     DataType.WORD to DataType.ARRAY_W,
     DataType.UWORD to DataType.ARRAY_UW,
     DataType.FLOAT to DataType.ARRAY_F,
-    DataType.BOOL to DataType.ARRAY_BOOL
+    DataType.BOOL to DataType.ARRAY_BOOL,
+    DataType.STR to DataType.ARRAY_UW          // array of str is just an array of pointers
 )
+
 val Cx16VirtualRegisters = arrayOf(
     RegisterOrPair.R0, RegisterOrPair.R1, RegisterOrPair.R2, RegisterOrPair.R3,
     RegisterOrPair.R4, RegisterOrPair.R5, RegisterOrPair.R6, RegisterOrPair.R7,
@@ -159,6 +171,10 @@ val Cx16VirtualRegisters = arrayOf(
     RegisterOrPair.R12, RegisterOrPair.R13, RegisterOrPair.R14, RegisterOrPair.R15
 )
 
+val CpuRegisters = setOf(
+    RegisterOrPair.A, RegisterOrPair.X, RegisterOrPair.Y,
+    RegisterOrPair.AX, RegisterOrPair.AY, RegisterOrPair.XY
+)
 
 
 enum class OutputType {

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

@@ -3,8 +3,6 @@ package prog8.code.core
 interface ICompilationTarget: IStringEncoding, IMemSizer {
     val name: String
     val machine: IMachineDefinition
-    val supportedEncodings: Set<Encoding>
-    val defaultEncoding: Encoding
 
     override fun encodeString(str: String, encoding: Encoding): List<UByte>
     override fun decodeString(bytes: Iterable<UByte>, encoding: Encoding): String

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

@@ -3,11 +3,12 @@ package prog8.code.core
 interface IErrorReporter {
     fun err(msg: String, position: Position)
     fun warn(msg: String, position: Position)
+    fun info(msg: String, position: Position)
     fun undefined(symbol: List<String>, position: Position)
     fun noErrors(): Boolean
     fun report()
-    fun finalizeNumErrors(numErrors: Int, numWarnings: Int) {
+    fun finalizeNumErrors(numErrors: Int, numWarnings: Int, numInfos: Int) {
         if(numErrors>0)
-            throw ErrorsReportedException("There are $numErrors errors and $numWarnings warnings.")
+            throw ErrorsReportedException("There are $numErrors errors, $numWarnings warnings, and $numInfos infos.")
     }
 }

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

@@ -13,11 +13,11 @@ interface IMachineDefinition {
     val FLOAT_MAX_NEGATIVE: Double
     val FLOAT_MAX_POSITIVE: Double
     val FLOAT_MEM_SIZE: Int
-    var ESTACK_LO: UInt
-    var ESTACK_HI: UInt
     val PROGRAM_LOAD_ADDRESS : UInt
     val BSSHIGHRAM_START: UInt
     val BSSHIGHRAM_END: UInt
+    val BSSGOLDENRAM_START: UInt
+    val BSSGOLDENRAM_END: UInt
 
     val cpu: CpuType
     var zeropage: Zeropage
@@ -29,11 +29,4 @@ interface IMachineDefinition {
     fun importLibs(compilerOptions: CompilationOptions, compilationTargetName: String): List<String>
     fun launchEmulator(selectedEmulator: Int, programNameWithPath: Path)
     fun isIOAddress(address: UInt): Boolean
-    fun overrideEvalStack(evalStackBaseAddress: UInt) {
-        require(evalStackBaseAddress and 255u == 0u)
-        ESTACK_LO = evalStackBaseAddress
-        ESTACK_HI = evalStackBaseAddress + 256u
-        require(ESTACK_LO !in golden.region && ESTACK_HI !in golden.region) { "user-set ESTACK can't be in GOLDEN ram" }
-    }
-
 }

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

@@ -9,6 +9,8 @@ enum class Encoding(val prefix: String) {
 }
 
 interface IStringEncoding {
+    val defaultEncoding: Encoding
+
     fun encodeString(str: String, encoding: Encoding): List<UByte>
     fun decodeString(bytes: Iterable<UByte>, encoding: Encoding): String
 }

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

@@ -42,6 +42,13 @@ abstract class Zeropage(options: CompilationOptions): MemoryAllocator(options) {
         }
     }
 
+    fun retainAllowed() {
+        synchronized(this) {
+            for(allowed in options.zpAllowed)
+                free.retainAll { it in allowed }
+        }
+    }
+
     fun availableBytes() = if(options.zeropage== ZeropageType.DONTUSE) 0 else free.size
     fun hasByteAvailable() = if(options.zeropage== ZeropageType.DONTUSE) false else free.isNotEmpty()
     fun hasWordAvailable(): Boolean {

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

@@ -1,12 +1,10 @@
 package prog8.code.core
 
-val AssociativeOperators = setOf("+", "*", "&", "|", "^", "==", "!=")
+val AssociativeOperators = setOf("+", "*", "&", "|", "^", "==", "!=", "and", "or", "xor")
 val ComparisonOperators = setOf("==", "!=", "<", ">", "<=", ">=")
 val LogicalOperators = setOf("and", "or", "xor", "not")
-val AugmentAssignmentOperators = setOf("+", "-", "/", "*", "&", "|", "^", "<<", ">>", "%", "and", "or", "xor")
 val BitwiseOperators = setOf("&", "|", "^", "~")
 val PrefixOperators = setOf("+", "-", "~", "not")
-// val InvalidOperatorsForBoolean = setOf("+", "-", "*", "/", "%", "<<", ">>") + BitwiseOperators
 
 fun invertedComparisonOperator(operator: String) =
     when (operator) {

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

@@ -1,6 +1,6 @@
 package prog8.code.core
 
-import prog8.code.core.SourceCode.Companion.libraryFilePrefix
+import prog8.code.core.SourceCode.Companion.LIBRARYFILEPREFIX
 import java.nio.file.InvalidPathException
 import kotlin.io.path.Path
 import kotlin.io.path.absolute
@@ -10,7 +10,7 @@ data class Position(val file: String, val line: Int, val startCol: Int, val endC
     fun toClickableStr(): String {
         if(this===DUMMY)
             return ""
-        if(file.startsWith(libraryFilePrefix))
+        if(file.startsWith(LIBRARYFILEPREFIX))
             return "$file:$line:$startCol:"
         return try {
             val path = Path(file).absolute().normalize().toString()

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

@@ -3,6 +3,7 @@ package prog8.code.core
 import java.io.File
 import java.io.IOException
 import java.nio.file.Path
+import java.text.Normalizer
 import kotlin.io.path.Path
 import kotlin.io.path.readText
 
@@ -54,22 +55,25 @@ sealed class SourceCode {
         /**
          * filename prefix to designate library files that will be retreived from internal resources rather than disk
          */
-        const val libraryFilePrefix = "library:"
-        const val stringSourcePrefix = "string:"
+        const val LIBRARYFILEPREFIX = "library:"
+        const val STRINGSOURCEPREFIX = "string:"
         val curdir: Path = Path(".").toAbsolutePath()
         fun relative(path: Path): Path = curdir.relativize(path.toAbsolutePath())
         fun isRegularFilesystemPath(pathString: String) =
-            !(pathString.startsWith(libraryFilePrefix) || pathString.startsWith(stringSourcePrefix))
+            !(pathString.startsWith(LIBRARYFILEPREFIX) || pathString.startsWith(STRINGSOURCEPREFIX))
+
+        fun isLibraryResource(path: String) = path.startsWith(LIBRARYFILEPREFIX)
     }
 
     /**
      * Turn a plain String into a [SourceCode] object.
      * [origin] will be something like `string:44c56085`.
      */
-    class Text(override val text: String): SourceCode() {
+    class Text(origText: String): SourceCode() {
+        override val text = origText.replace("\\R".toRegex(), "\n")      // normalize line endings
         override val isFromResources = false
         override val isFromFilesystem = false
-        override val origin = "$stringSourcePrefix${System.identityHashCode(text).toString(16)}"
+        override val origin = "$STRINGSOURCEPREFIX${System.identityHashCode(text).toString(16)}"
         override val name = "<unnamed-text>"
     }
 
@@ -92,7 +96,8 @@ sealed class SourceCode {
             val normalized = path.normalize()
             origin = relative(normalized).toString()
             try {
-                text = normalized.readText()
+                val contents = Normalizer.normalize(normalized.readText(), Normalizer.Form.NFC)
+                text = contents.replace("\\R".toRegex(), "\n")      // normalize line endings
                 name = normalized.toFile().nameWithoutExtension
             } catch (nfx: java.nio.file.NoSuchFileException) {
                 throw NoSuchFileException(normalized.toFile()).also { it.initCause(nfx) }
@@ -110,7 +115,7 @@ sealed class SourceCode {
 
         override val isFromResources = true
         override val isFromFilesystem = false
-        override val origin = "$libraryFilePrefix$normalized"
+        override val origin = "$LIBRARYFILEPREFIX$normalized"
         override val text: String
         override val name: String
 
@@ -124,7 +129,8 @@ sealed class SourceCode {
                 )
             }
             val stream = object {}.javaClass.getResourceAsStream(normalized)
-            text = stream!!.reader().use { it.readText() }
+            val contents = stream!!.reader().use { Normalizer.normalize(it.readText(), Normalizer.Form.NFC) }
+            text = contents.replace("\\R".toRegex(), "\n")      // normalize line endings
             name = Path(pathString).toFile().nameWithoutExtension
         }
     }
@@ -139,3 +145,33 @@ sealed class SourceCode {
         override val text: String = "<generated code node, no text representation>"
     }
 }
+
+
+object SourceLineCache {
+    private val cache = mutableMapOf<String, List<String>>()
+
+    private fun getCachedFile(file: String): List<String> {
+        val existing = cache[file]
+        if(existing!=null)
+            return existing
+        if (SourceCode.isRegularFilesystemPath(file)) {
+            val source = SourceCode.File(Path(file))
+            cache[file] = source.text.split('\n', '\r').map { it.trim() }
+            return cache.getValue(file)
+        } else if(file.startsWith(SourceCode.LIBRARYFILEPREFIX)) {
+            val source = SourceCode.Resource(file.drop(SourceCode.LIBRARYFILEPREFIX.length))
+            cache[file] = source.text.split('\n', '\r').map { it.trim()}
+            return cache.getValue(file)
+        }
+        return emptyList()
+    }
+
+    fun retrieveLine(position: Position): String? {
+        if (position.line>0) {
+            val lines = getCachedFile(position.file)
+            if(lines.isNotEmpty())
+                return lines[position.line-1]
+        }
+        return null
+    }
+}

codeCore/src/prog8/code/optimize/Optimizer.kt

@@ -0,0 +1,130 @@
+package prog8.code.optimize
+
+import prog8.code.ast.*
+import prog8.code.core.*
+
+
+fun optimizeIntermediateAst(program: PtProgram, options: CompilationOptions, errors: IErrorReporter) {
+    if (!options.optimize)
+        return
+    while(errors.noErrors() && optimizeCommonSubExpressions(program, errors)>0) {
+        // keep rolling
+    }
+}
+
+
+private fun walkAst(root: PtNode, act: (node: PtNode, depth: Int) -> Boolean) {
+    fun recurse(node: PtNode, depth: Int) {
+        if(act(node, depth))
+            node.children.forEach { recurse(it, depth+1) }
+    }
+    recurse(root, 0)
+}
+
+
+private var tempVarCounter = 0
+
+private fun optimizeCommonSubExpressions(program: PtProgram, errors: IErrorReporter): Int {
+
+    fun extractableSubExpr(expr: PtExpression): Boolean {
+        val result = if(expr is PtBinaryExpression)
+            expr.type !in ByteDatatypes ||
+                    !expr.left.isSimple() ||
+                    !expr.right.isSimple() ||
+                    (expr.operator !in LogicalOperators && expr.operator !in BitwiseOperators)
+        else if (expr is PtArrayIndexer && expr.type !in ByteDatatypes)
+            true
+        else
+            !expr.isSimple()
+        return result
+    }
+
+    // for each Binaryexpression, recurse to find a common subexpression pair therein.
+    val commons = mutableMapOf<PtBinaryExpression, Pair<PtExpression, PtExpression>>()
+    walkAst(program) { node: PtNode, depth: Int ->
+        if(node is PtBinaryExpression) {
+            val subExpressions = mutableListOf<PtExpression>()
+            walkAst(node.left) { subNode: PtNode, subDepth: Int ->
+                if (subNode is PtExpression) {
+                    if(extractableSubExpr(subNode)) subExpressions.add(subNode)
+                    true
+                } else false
+            }
+            walkAst(node.right) { subNode: PtNode, subDepth: Int ->
+                if (subNode is PtExpression) {
+                    if(extractableSubExpr(subNode)) subExpressions.add(subNode)
+                    true
+                } else false
+            }
+
+            outer@for (first in subExpressions) {
+                for (second in subExpressions) {
+                    if (first!==second && first isSameAs second) {
+                        commons[node] = first to second
+                        break@outer     // do only 1 replacement at a time per binaryexpression
+                    }
+                }
+            }
+            false
+        } else true
+    }
+
+    // replace common subexpressions by a temp variable that is assigned only once.
+    // TODO: check for commonalities across multiple separate expressions in the current scope, not only inside a single line
+    commons.forEach { binexpr, (occurrence1, occurrence2) ->
+        val (stmtContainer, stmt) = findContainingStatements(binexpr)
+        val occurrence1idx = occurrence1.parent.children.indexOf(occurrence1)
+        val occurrence2idx = occurrence2.parent.children.indexOf(occurrence2)
+        val containerScopedName = findScopeName(stmtContainer)
+        tempVarCounter++
+        val tempvarName = "prog8_subexprvar_$tempVarCounter"
+        // TODO: some tempvars could be reused, if they are from different lines
+
+        val datatype = occurrence1.type
+        val singleReplacement1 = PtIdentifier("$containerScopedName.$tempvarName", datatype, occurrence1.position)
+        val singleReplacement2 = PtIdentifier("$containerScopedName.$tempvarName", datatype, occurrence2.position)
+        occurrence1.parent.children[occurrence1idx] = singleReplacement1
+        singleReplacement1.parent = occurrence1.parent
+        occurrence2.parent.children[occurrence2idx] = singleReplacement2
+        singleReplacement2.parent = occurrence2.parent
+
+        val tempassign = PtAssignment(binexpr.position).also { assign ->
+            assign.add(PtAssignTarget(binexpr.position).also { tgt->
+                tgt.add(PtIdentifier("$containerScopedName.$tempvarName", datatype, binexpr.position))
+            })
+            assign.add(occurrence1)
+            occurrence1.parent = assign
+        }
+        stmtContainer.children.add(stmtContainer.children.indexOf(stmt), tempassign)
+        tempassign.parent = stmtContainer
+
+        val tempvar = PtVariable(tempvarName, datatype, ZeropageWish.NOT_IN_ZEROPAGE, null, null, binexpr.position)
+        stmtContainer.add(0, tempvar)
+        tempvar.parent = stmtContainer
+
+        // errors.info("common subexpressions replaced by a tempvar, maybe simplify the expression manually", binexpr.position)
+    }
+
+    return commons.size
+}
+
+
+internal fun findScopeName(node: PtNode): String {
+    var parent=node
+    while(parent !is PtNamedNode)
+        parent = parent.parent
+    return parent.scopedName
+}
+
+
+internal fun findContainingStatements(node: PtNode): Pair<PtNode, PtNode> {      // returns (parentstatementcontainer, childstatement)
+    var parent = node.parent
+    var child = node
+    while(true) {
+        if(parent is IPtStatementContainer) {
+            return parent to child
+        }
+        child=parent
+        parent=parent.parent
+    }
+}

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

@@ -7,7 +7,6 @@ import prog8.code.target.atari.AtariMachineDefinition
 class AtariTarget: ICompilationTarget, IStringEncoding by Encoder, IMemSizer {
     override val name = NAME
     override val machine = AtariMachineDefinition()
-    override val supportedEncodings = setOf(Encoding.ATASCII)
     override val defaultEncoding = Encoding.ATASCII
 
     companion object {
@@ -19,7 +18,7 @@ class AtariTarget: ICompilationTarget, IStringEncoding by Encoder, IMemSizer {
             in ByteDatatypes -> 1
             in WordDatatypes, in PassByReferenceDatatypes -> 2
             DataType.FLOAT -> machine.FLOAT_MEM_SIZE
-            else -> Int.MIN_VALUE
+            else -> throw IllegalArgumentException("invalid datatype")
         }
     }
 

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

@@ -11,7 +11,6 @@ import prog8.code.target.cbm.CbmMemorySizer
 class C128Target: ICompilationTarget, IStringEncoding by Encoder, IMemSizer by CbmMemorySizer {
     override val name = NAME
     override val machine = C128MachineDefinition()
-    override val supportedEncodings = setOf(Encoding.PETSCII, Encoding.SCREENCODES)
     override val defaultEncoding = Encoding.PETSCII
 
     companion object {

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

@@ -11,7 +11,6 @@ import prog8.code.target.cbm.CbmMemorySizer
 class C64Target: ICompilationTarget, IStringEncoding by Encoder, IMemSizer by CbmMemorySizer {
     override val name = NAME
     override val machine = C64MachineDefinition()
-    override val supportedEncodings = setOf(Encoding.PETSCII, Encoding.SCREENCODES)
     override val defaultEncoding = Encoding.PETSCII
 
     companion object {

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

@@ -11,7 +11,6 @@ import prog8.code.target.cx16.CX16MachineDefinition
 class Cx16Target: ICompilationTarget, IStringEncoding by Encoder, IMemSizer by CbmMemorySizer {
     override val name = NAME
     override val machine = CX16MachineDefinition()
-    override val supportedEncodings = setOf(Encoding.PETSCII, Encoding.SCREENCODES, Encoding.ISO)
     override val defaultEncoding = Encoding.PETSCII
 
     companion object {

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

@@ -10,6 +10,8 @@ import prog8.code.target.cbm.PetsciiEncoding
 
 
 object Encoder: IStringEncoding {
+    override val defaultEncoding: Encoding = Encoding.ISO
+
     override fun encodeString(str: String, encoding: Encoding): List<UByte> {
         val coded = when(encoding) {
             Encoding.PETSCII -> PetsciiEncoding.encodePetscii(str, true)

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

@@ -0,0 +1,19 @@
+package prog8.code.target
+
+import prog8.code.core.Encoding
+import prog8.code.core.ICompilationTarget
+import prog8.code.core.IMemSizer
+import prog8.code.core.IStringEncoding
+import prog8.code.target.cbm.CbmMemorySizer
+import prog8.code.target.pet.PETMachineDefinition
+
+
+class PETTarget: ICompilationTarget, IStringEncoding by Encoder, IMemSizer by CbmMemorySizer {
+    override val name = NAME
+    override val machine = PETMachineDefinition()
+    override val defaultEncoding = Encoding.PETSCII
+
+    companion object {
+        const val NAME = "pet32"
+    }
+}

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

@@ -6,7 +6,6 @@ import prog8.code.target.virtual.VirtualMachineDefinition
 class VMTarget: ICompilationTarget, IStringEncoding by Encoder, IMemSizer {
     override val name = NAME
     override val machine = VirtualMachineDefinition()
-    override val supportedEncodings = setOf(Encoding.ISO)
     override val defaultEncoding = Encoding.ISO
 
     companion object {
@@ -18,7 +17,7 @@ class VMTarget: ICompilationTarget, IStringEncoding by Encoder, IMemSizer {
             in ByteDatatypes -> 1
             in WordDatatypes, in PassByReferenceDatatypes -> 2
             DataType.FLOAT -> machine.FLOAT_MEM_SIZE
-            else -> Int.MIN_VALUE
+            else -> throw IllegalArgumentException("invalid datatype")
         }
     }
 

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

@@ -13,12 +13,10 @@ class AtariMachineDefinition: IMachineDefinition {
     override val FLOAT_MEM_SIZE = 6
     override val PROGRAM_LOAD_ADDRESS = 0x2000u
 
-    // the 2*128 byte evaluation stack (1 page, on which bytes, words, and even floats are stored during calculations)
-    override var ESTACK_LO = 0x1b00u     //  $1b00-$1b7f inclusive      // TODO
-    override var ESTACK_HI = 0x1b80u     //  $1b80-$1bff inclusive      // TODO
-
     override val BSSHIGHRAM_START = 0u    // TODO
     override val BSSHIGHRAM_END = 0u      // TODO
+    override val BSSGOLDENRAM_START = 0u  // TODO
+    override val BSSGOLDENRAM_END = 0u    // TODO
 
     override lateinit var zeropage: Zeropage
     override lateinit var golden: GoldenRam

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

@@ -48,6 +48,7 @@ class AtariZeropage(options: CompilationOptions) : Zeropage(options) {
         free.addAll(distinctFree)
 
         removeReservedFromFreePool()
+        retainAllowed()
     }
 
     override fun allocateCx16VirtualRegisters() {

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

@@ -15,12 +15,10 @@ class C128MachineDefinition: IMachineDefinition {
     override val FLOAT_MEM_SIZE = Mflpt5.FLOAT_MEM_SIZE
     override val PROGRAM_LOAD_ADDRESS = 0x1c01u
 
-    // the 2*128 byte evaluation stack (1 page, on which bytes, words, and even floats are stored during calculations)
-    override var ESTACK_LO = 0x1b00u     //  $1b00-$1b7f inclusive
-    override var ESTACK_HI = 0x1b80u     //  $1b80-$1bff inclusive
-
     override val BSSHIGHRAM_START = 0u    // TODO
     override val BSSHIGHRAM_END = 0u      // TODO
+    override val BSSGOLDENRAM_START = 0u  // TODO
+    override val BSSGOLDENRAM_END = 0u    // TODO
 
     override lateinit var zeropage: Zeropage
     override lateinit var golden: GoldenRam

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

@@ -69,6 +69,7 @@ class C128Zeropage(options: CompilationOptions) : Zeropage(options) {
         free.addAll(distinctFree)
 
         removeReservedFromFreePool()
+        retainAllowed()
     }
 
     override fun allocateCx16VirtualRegisters() {

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

@@ -16,12 +16,10 @@ class C64MachineDefinition: IMachineDefinition {
     override val FLOAT_MEM_SIZE = Mflpt5.FLOAT_MEM_SIZE
     override val PROGRAM_LOAD_ADDRESS = 0x0801u
 
-    // the 2*128 byte evaluation stack (1 page, on which bytes, words, and even floats are stored during calculations)
-    override var ESTACK_LO = 0xcf00u     //  $cf00-$cf7f inclusive
-    override var ESTACK_HI = 0xcf80u     //  $cf80-$cfff inclusive
-
     override val BSSHIGHRAM_START = 0xc000u
-    override val BSSHIGHRAM_END = ESTACK_LO
+    override val BSSHIGHRAM_END = 0xcfffu
+    override val BSSGOLDENRAM_START = 0u
+    override val BSSGOLDENRAM_END = 0u
 
     override lateinit var zeropage: Zeropage
     override lateinit var golden: GoldenRam
@@ -62,7 +60,7 @@ class C64MachineDefinition: IMachineDefinition {
 
     override fun initializeMemoryAreas(compilerOptions: CompilationOptions) {
         zeropage = C64Zeropage(compilerOptions)
-        golden = GoldenRam(compilerOptions, 0xc000u until ESTACK_LO)
+        golden = GoldenRam(compilerOptions, 0xc000u until 0xd000u)
     }
 
 }

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

@@ -53,11 +53,11 @@ class C64Zeropage(options: CompilationOptions) : Zeropage(options) {
                 ).map{it.toUInt()})
             }
 
-            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(0x02, 0x03, 0x04, 0x05, 0x06, 0x0a, 0x0e,
-                        0x92, 0x96, 0x9b, 0x9c, 0x9e, 0x9f, 0xa5, 0xa6,
+                        0x92, 0x96, 0x9b, 0x9c, 0x9e, 0x9f, 0xa6,
                         0xb0, 0xb1, 0xbe, 0xbf, 0xf9).map{it.toUInt()})
             } else {
                 // don't use the zeropage at all
@@ -75,6 +75,8 @@ class C64Zeropage(options: CompilationOptions) : Zeropage(options) {
             // in these cases there is enough space on the zero page to stick the cx16 virtual registers in there as well.
             allocateCx16VirtualRegisters()
         }
+
+        retainAllowed()
     }
 
     override fun allocateCx16VirtualRegisters() {

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

@@ -9,7 +9,7 @@ internal object CbmMemorySizer: IMemSizer {
             in ByteDatatypes -> 1
             in WordDatatypes, in PassByReferenceDatatypes -> 2
             DataType.FLOAT -> Mflpt5.FLOAT_MEM_SIZE
-            else -> Int.MIN_VALUE
+            else -> throw IllegalArgumentException("invalid datatype")
         }
     }
 

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

@@ -24,7 +24,7 @@ object PetsciiEncoding {
         '\ufffe',    //       0x0A -> UNDEFINED
         '\ufffe',    //       0x0B -> UNDEFINED
         '\ufffe',    //       0x0C -> UNDEFINED
-        '\r'    ,    //       0x0D -> CARRIAGE RETURN
+        '\n'    ,    //       0x0D -> LINE FEED (RETURN)
         '\u000e',    //       0x0E -> SHIFT OUT
         '\ufffe',    //       0x0F -> UNDEFINED
         '\ufffe',    //       0x10 -> UNDEFINED
@@ -152,7 +152,7 @@ object PetsciiEncoding {
         '\uf113',    //      0x8A -> FUNCTION KEY 4 (CUS)
         '\uf115',    //      0x8B -> FUNCTION KEY 6 (CUS)
         '\uf117',    //      0x8C -> FUNCTION KEY 8 (CUS)
-        '\n'    ,    //       0x8D -> LINE FEED
+        '\r'    ,    //       0x8D -> CARRIAGE RETURN (SHIFT-RETURN)
         '\u000f',    //      0x8E -> SHIFT IN
         '\ufffe',    //       0x8F -> UNDEFINED
         '\uf105',    //       0x90 -> BLACK COLOR SWITCH (CUS)
@@ -283,7 +283,7 @@ object PetsciiEncoding {
         '\ufffe',    //       0x0A -> UNDEFINED
         '\ufffe',    //       0x0B -> UNDEFINED
         '\ufffe',    //       0x0C -> UNDEFINED
-        '\r'    ,    //       0x0D -> CARRIAGE RETURN
+        '\n'    ,    //       0x0D -> LINE FEED (RETURN)
         '\u000e',    //       0x0E -> SHIFT OUT
         '\ufffe',    //       0x0F -> UNDEFINED
         '\ufffe',    //       0x10 -> UNDEFINED
@@ -411,7 +411,7 @@ object PetsciiEncoding {
         '\uf113',    //       0x8A -> FUNCTION KEY 4 (CUS)
         '\uf115',    //       0x8B -> FUNCTION KEY 6 (CUS)
         '\uf117',    //       0x8C -> FUNCTION KEY 8 (CUS)
-        '\n'    ,    //       0x8D -> LINE FEED
+        '\r'    ,    //       0x8D -> CARRIAGE RETURN (SHIFT-RETURN)
         '\u000f',    //       0x8E -> SHIFT IN
         '\ufffe',    //       0x8F -> UNDEFINED
         '\uf105',    //       0x90 -> BLACK COLOR SWITCH (CUS)
@@ -1061,6 +1061,7 @@ object PetsciiEncoding {
             '}' -> '├'
             '|' -> '│'
             '\\' -> '╲'
+            '\r' -> '\n'        // to make \r (carriage returrn) equivalent to \n (line feed): RETURN ($0d)
             else -> chr
         }
 
@@ -1076,7 +1077,10 @@ object PetsciiEncoding {
                 }
                 else -> {
                     val case = if (lowercase) "lower" else "upper"
-                    throw CharConversionException("no ${case}Petscii character for '${chr}' (${chr.code})")
+                    if(chr.isISOControl())
+                        throw CharConversionException("no ${case}Petscii character for char #${chr.code}")
+                    else
+                        throw CharConversionException("no ${case}Petscii character for char #${chr.code} '${chr}'")
                 }
             }
         }
@@ -1119,7 +1123,10 @@ object PetsciiEncoding {
                 }
                 else -> {
                     val case = if (lowercase) "lower" else "upper"
-                    throw CharConversionException("no ${case}Screencode character for '${chr}' (${chr.code})")
+                    if(chr.isISOControl())
+                        throw CharConversionException("no ${case}Screencode character for char #${chr.code}")
+                    else
+                        throw CharConversionException("no ${case}Screencode character for char #${chr.code} '${chr}'")
                 }
             }
         }

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

@@ -15,12 +15,10 @@ class CX16MachineDefinition: IMachineDefinition {
     override val FLOAT_MEM_SIZE = Mflpt5.FLOAT_MEM_SIZE
     override val PROGRAM_LOAD_ADDRESS = 0x0801u
 
-    // the 2*128 byte evaluation stack (1 page, on which bytes, words, and even floats are stored during calculations)
-    override var ESTACK_LO = 0x0700u        //  $0700-$077f inclusive
-    override var ESTACK_HI = 0x0780u        //  $0780-$07ff inclusive
-
     override val BSSHIGHRAM_START = 0xa000u     // hiram bank 1, 8Kb, assumed to be active
-    override val BSSHIGHRAM_END = 0xc000u       // rom starts here.
+    override val BSSHIGHRAM_END = 0xbfffu       // Rom starts at $c000
+    override val BSSGOLDENRAM_START = 0x0400u
+    override val BSSGOLDENRAM_END = 0x07ffu
 
     override lateinit var zeropage: Zeropage
     override lateinit var golden: GoldenRam
@@ -40,7 +38,7 @@ class CX16MachineDefinition: IMachineDefinition {
         when(selectedEmulator) {
             1 -> {
                 emulator = "x16emu"
-                extraArgs = emptyList()
+                extraArgs = listOf("-debug")
             }
             2 -> {
                 emulator = "box16"
@@ -53,7 +51,7 @@ class CX16MachineDefinition: IMachineDefinition {
         }
 
         println("\nStarting Commander X16 emulator $emulator...")
-        val cmdline = listOf(emulator, "-scale", "2", "-run", "-prg", "${programNameWithPath}.prg") + extraArgs
+        val cmdline = listOf(emulator, "-scale", "2", "-rtc", "-run", "-prg", "${programNameWithPath}.prg") + extraArgs
         val processb = ProcessBuilder(cmdline).inheritIO()
         processb.environment()["PULSE_LATENCY_MSEC"] = "10"
         val process: Process = processb.start()
@@ -64,7 +62,7 @@ class CX16MachineDefinition: IMachineDefinition {
 
     override fun initializeMemoryAreas(compilerOptions: CompilationOptions) {
         zeropage = CX16Zeropage(compilerOptions)
-        golden = GoldenRam(compilerOptions, 0x0400u until ESTACK_LO)
+        golden = GoldenRam(compilerOptions, 0x0400u until 0x0800u)
     }
 
 }

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

@@ -40,7 +40,6 @@ class CX16Zeropage(options: CompilationOptions) : Zeropage(options) {
                 ZeropageType.DONTUSE -> {
                     free.clear() // don't use zeropage at all
                 }
-                else -> throw InternalCompilerException("for this machine target, zero page type 'floatsafe' is not available. ${options.zeropage}")
             }
 
             val distinctFree = free.distinct()
@@ -48,8 +47,8 @@ class CX16Zeropage(options: CompilationOptions) : Zeropage(options) {
             free.addAll(distinctFree)
 
             removeReservedFromFreePool()
-
             allocateCx16VirtualRegisters()
+            retainAllowed()
         }
     }
 

codeCore/src/prog8/code/target/pet/PETMachineDefinition.kt

@@ -0,0 +1,57 @@
+package prog8.code.target.pet
+
+import prog8.code.core.*
+import prog8.code.target.C64Target
+import prog8.code.target.cbm.Mflpt5
+import java.nio.file.Path
+
+
+class PETMachineDefinition: IMachineDefinition {
+
+    override val cpu = CpuType.CPU6502
+
+    override val FLOAT_MAX_POSITIVE = Mflpt5.FLOAT_MAX_POSITIVE
+    override val FLOAT_MAX_NEGATIVE = Mflpt5.FLOAT_MAX_NEGATIVE
+    override val FLOAT_MEM_SIZE = Mflpt5.FLOAT_MEM_SIZE
+    override val PROGRAM_LOAD_ADDRESS = 0x0401u
+
+    override val BSSHIGHRAM_START = 0u
+    override val BSSHIGHRAM_END = 0u
+    override val BSSGOLDENRAM_START = 0u
+    override val BSSGOLDENRAM_END = 0u
+
+    override lateinit var zeropage: Zeropage
+    override lateinit var golden: GoldenRam
+
+    override fun getFloatAsmBytes(num: Number) = Mflpt5.fromNumber(num).makeFloatFillAsm()
+
+    override fun importLibs(compilerOptions: CompilationOptions, compilationTargetName: String): List<String> {
+        return if (compilerOptions.launcher == CbmPrgLauncherType.BASIC || compilerOptions.output == OutputType.PRG)
+            listOf("syslib")
+        else
+            emptyList()
+    }
+
+    override fun launchEmulator(selectedEmulator: Int, programNameWithPath: Path) {
+        if(selectedEmulator!=1) {
+            System.err.println("The pet target only supports the main emulator (Vice).")
+            return
+        }
+
+        println("\nStarting PET emulator...")
+        val viceMonlist = C64Target.viceMonListName(programNameWithPath.toString())
+        val cmdline = listOf("xpet", "-model", "4032", "-ramsize", "32", "-videosize", "40", "-silent", "-moncommands", viceMonlist,
+                "-autostartprgmode", "1", "-autostart-warp", "-autostart", "${programNameWithPath}.prg")
+        val processb = ProcessBuilder(cmdline).inheritIO()
+        val process=processb.start()
+        process.waitFor()
+    }
+
+    override fun isIOAddress(address: UInt): Boolean = address in 0xe800u..0xe8ffu
+
+    override fun initializeMemoryAreas(compilerOptions: CompilationOptions) {
+        zeropage = PETZeropage(compilerOptions)
+        // there's no golden ram.
+    }
+
+}

codeCore/src/prog8/code/target/pet/PETZeropage.kt

@@ -0,0 +1,59 @@
+package prog8.code.target.pet
+
+import prog8.code.core.CompilationOptions
+import prog8.code.core.InternalCompilerException
+import prog8.code.core.Zeropage
+import prog8.code.core.ZeropageType
+
+
+// reference: http://www.zimmers.net/cbmpics/cbm/PETx/petmem.txt
+
+class PETZeropage(options: CompilationOptions) : Zeropage(options) {
+
+    override val SCRATCH_B1 = 0xb3u      // temp storage for a single byte
+    override val SCRATCH_REG = 0xb4u     // temp storage for a register, must be B1+1
+    override val SCRATCH_W1 = 0xb6u      // temp storage 1 for a word
+    override val SCRATCH_W2 = 0xb8u      // temp storage 2 for a word
+
+    init {
+        if (options.floats) {
+            throw InternalCompilerException("PET target doesn't yet support floating point routines")
+        }
+
+        if (options.floats && options.zeropage !in arrayOf(
+                ZeropageType.FLOATSAFE,
+                ZeropageType.BASICSAFE,
+                ZeropageType.DONTUSE
+            ))
+            throw InternalCompilerException("when floats are enabled, zero page type should be 'floatsafe' or 'basicsafe' or 'dontuse'")
+
+        when (options.zeropage) {
+            ZeropageType.FULL -> {
+                free.addAll(0x00u..0xffu)
+                free.removeAll(listOf(0x8du, 0x8eu, 0x8fu, 0x97u, 0x98u, 0x99u, 0x9au, 0x9bu, 0x9eu, 0xa7u, 0xa8u, 0xa9u, 0xaau))        // these are updated/used by IRQ
+            }
+            ZeropageType.KERNALSAFE -> {
+                free.addAll(0x00u..0xffu)
+                free.removeAll(listOf(0x8du, 0x8eu, 0x8fu, 0x97u, 0x98u, 0x99u, 0x9au, 0x9bu, 0x9eu, 0xa7u, 0xa8u, 0xa9u, 0xaau))        // these are updated/used by IRQ
+            }
+            ZeropageType.FLOATSAFE,
+            ZeropageType.BASICSAFE -> {
+                free.addAll(0xb3u..0xbau)       // TODO more?
+            }
+            ZeropageType.DONTUSE -> {
+                free.clear()  // don't use zeropage at all
+            }
+        }
+
+        val distinctFree = free.distinct()
+        free.clear()
+        free.addAll(distinctFree)
+
+        removeReservedFromFreePool()
+        retainAllowed()
+    }
+
+    override fun allocateCx16VirtualRegisters() {
+        TODO("Not known if PET can put the virtual regs in ZP")
+    }
+}

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

@@ -12,20 +12,20 @@ class VirtualMachineDefinition: IMachineDefinition {
 
     override val FLOAT_MAX_POSITIVE = Float.MAX_VALUE.toDouble()
     override val FLOAT_MAX_NEGATIVE = -Float.MAX_VALUE.toDouble()
-    override val FLOAT_MEM_SIZE = 4             // 32-bits floating point
+    override val FLOAT_MEM_SIZE = 8             // 64-bits double
     override val PROGRAM_LOAD_ADDRESS = 0u      // not actually used
 
-    override var ESTACK_LO = 0u                 // not actually used
-    override var ESTACK_HI = 0u                 // not actually used
     override val BSSHIGHRAM_START = 0u          // not actually used
     override val BSSHIGHRAM_END = 0u            // not actually used
+    override val BSSGOLDENRAM_START = 0u        // not actually used
+    override val BSSGOLDENRAM_END = 0u          // not actually used
     override lateinit var zeropage: Zeropage    // not actually used
     override lateinit var golden: GoldenRam     // not actually used
 
     override fun getFloatAsmBytes(num: Number): String {
         // little endian binary representation
-        val bits = num.toFloat().toBits().toUInt()
-        val hexStr = bits.toString(16).padStart(8, '0')
+        val bits = num.toDouble().toBits().toULong()
+        val hexStr = bits.toString(16).padStart(16, '0')
         val parts = hexStr.chunked(2).map { "\$" + it }
         return parts.joinToString(", ")
     }

codeGenCpu6502/build.gradle

@@ -30,16 +30,16 @@ dependencies {
     // implementation "org.jetbrains.kotlin:kotlin-reflect"
     implementation "com.michael-bull.kotlin-result:kotlin-result-jvm:1.1.18"
 
-    testImplementation 'io.kotest:kotest-runner-junit5-jvm:5.6.2'
+    testImplementation 'io.kotest:kotest-runner-junit5-jvm:5.8.0'
 }
 
 sourceSets {
     main {
         java {
-            srcDirs = ["${project.projectDir}/src"]
+            srcDir "${project.projectDir}/src"
         }
         resources {
-            srcDirs = ["${project.projectDir}/res"]
+            srcDir "${project.projectDir}/res"
         }
     }
     test {

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

@@ -1,11 +1,13 @@
 package prog8.codegen.cpu6502
 
 import com.github.michaelbull.result.fold
+import prog8.code.StNode
 import prog8.code.StNodeType
 import prog8.code.SymbolTable
 import prog8.code.SymbolTableMaker
 import prog8.code.ast.*
 import prog8.code.core.*
+import prog8.code.target.Cx16Target
 import prog8.codegen.cpu6502.assignment.*
 import java.util.*
 import kotlin.io.path.Path
@@ -32,7 +34,14 @@ class AsmGen6502(val prefixSymbols: Boolean): ICodeGeneratorBackend {
         val functionCallsToPrefix = mutableListOf<Pair<PtNode, Int>>()      // parent + index
 
         fun prefixNamedNode(node: PtNamedNode) {
-            node.name = "p8_${node.name}"
+            when(node) {
+                is PtAsmSub, is PtSub -> node.name = "p8s_${node.name}"
+                is PtBlock -> node.name = "p8b_${node.name}"
+                is PtLabel -> node.name = "p8l_${node.name}"
+                is PtConstant -> node.name = "p8c_${node.name}"
+                is PtVariable, is PtMemMapped, is PtSubroutineParameter -> node.name = "p8v_${node.name}"
+                else -> node.name = "p8_${node.name}"
+            }
         }
 
         fun prefixSymbols(node: PtNode) {
@@ -47,7 +56,7 @@ class AsmGen6502(val prefixSymbols: Boolean): ICodeGeneratorBackend {
                 }
                 is PtFunctionCall -> {
                     val stNode = st.lookup(node.name)!!
-                    if(stNode.astNode.definingBlock()?.noSymbolPrefixing!=true) {
+                    if(stNode.astNode.definingBlock()?.options?.noSymbolPrefixing!=true) {
                         val index = node.parent.children.indexOf(node)
                         functionCallsToPrefix += node.parent to index
                     }
@@ -58,25 +67,16 @@ class AsmGen6502(val prefixSymbols: Boolean): ICodeGeneratorBackend {
                         lookupName = lookupName.dropLast(4)
                     }
                     val stNode = st.lookup(lookupName)!!
-                    if(stNode.astNode.definingBlock()?.noSymbolPrefixing!=true) {
+                    if(stNode.astNode.definingBlock()?.options?.noSymbolPrefixing!=true) {
                         val index = node.parent.children.indexOf(node)
                         nodesToPrefix += node.parent to index
                     }
                 }
                 is PtJump -> {
-                    if(node.identifier!=null) {
-                        val stNode = st.lookup(node.identifier!!.name)!!
-                        if(stNode.astNode.definingBlock()?.noSymbolPrefixing!=true) {
-                            val index = node.parent.children.indexOf(node)
-                            nodesToPrefix += node.parent to index
-                        }
-                    }
-                    else if(node.generatedLabel!=null) {
-                        val stNode = st.lookup(node.generatedLabel!!)!!
-                        if(stNode.astNode.definingBlock()?.noSymbolPrefixing!=true) {
-                            val index = node.parent.children.indexOf(node)
-                            nodesToPrefix += node.parent to index
-                        }
+                    val stNode = st.lookup(node.identifier!!.name) ?: throw AssemblyError("name not found ${node.identifier}")
+                    if(stNode.astNode.definingBlock()?.options?.noSymbolPrefixing!=true) {
+                        val index = node.parent.children.indexOf(node)
+                        nodesToPrefix += node.parent to index
                     }
                 }
                 is PtBlock -> prefixNamedNode(node)
@@ -94,7 +94,7 @@ class AsmGen6502(val prefixSymbols: Boolean): ICodeGeneratorBackend {
         }
 
         program.allBlocks().forEach { block ->
-            if (!block.noSymbolPrefixing) {
+            if (!block.options.noSymbolPrefixing) {
                 prefixSymbols(block)
             }
         }
@@ -124,8 +124,20 @@ class AsmGen6502(val prefixSymbols: Boolean): ICodeGeneratorBackend {
     }
 }
 
+private fun prefixScopedName(name: String, type: Char): String {
+    if('.' !in name)
+        return "p8${type}_$name"
+    val parts = name.split('.')
+    val firstPrefixed = "p8b_${parts[0]}"
+    val lastPrefixed = "p8${type}_${parts.last()}"
+    // the parts in between are assumed to be subroutine scopes.
+    val inbetweenPrefixed = parts.drop(1).dropLast(1).map{ "p8s_$it" }
+    val prefixed = listOf(firstPrefixed) + inbetweenPrefixed + listOf(lastPrefixed)
+    return prefixed.joinToString(".")
+}
+
 private fun PtVariable.prefix(st: SymbolTable): PtVariable {
-    name = name.split('.').map {"p8_$it" }.joinToString(".")
+    name = prefixScopedName(name, 'v')
     if(value==null)
         return this
 
@@ -137,7 +149,7 @@ private fun PtVariable.prefix(st: SymbolTable): PtVariable {
                 is PtIdentifier -> newValue.add(elt.prefix(arrayValue, st))
                 is PtNumber -> newValue.add(elt)
                 is PtAddressOf -> {
-                    if(elt.definingBlock()?.noSymbolPrefixing==true)
+                    if(elt.definingBlock()?.options?.noSymbolPrefixing==true)
                         newValue.add(elt)
                     else {
                         val newAddr = PtAddressOf(elt.position)
@@ -155,34 +167,45 @@ private fun PtVariable.prefix(st: SymbolTable): PtVariable {
 }
 
 private fun PtJump.prefix(parent: PtNode, st: SymbolTable): PtJump {
-    val jump = if(identifier!=null) {
-        val prefixedIdent = identifier!!.prefix(this, st)
-        PtJump(prefixedIdent, address, generatedLabel, position)
-    } else {
-        val prefixedLabel = generatedLabel!!.split('.').map {"p8_$it" }.joinToString(".")
-        PtJump(null, address, prefixedLabel, position)
-    }
+    val prefixedIdent = identifier!!.prefix(this, st)
+    val jump = PtJump(prefixedIdent, address, position)
     jump.parent = parent
     return jump
 }
 
 private fun PtFunctionCall.prefix(parent: PtNode): PtFunctionCall {
-    val newName = name.split('.').map {"p8_$it" }.joinToString(".")
+    val newName = prefixScopedName(name, 's')
     val call = PtFunctionCall(newName, void, type, position)
     call.children.addAll(children)
     call.children.forEach { it.parent = call }
     call.parent = parent
-    if(name.endsWith("concat_string"))
-        println("CONCAT ${this.position}")
     return call
 }
 
 private fun PtIdentifier.prefix(parent: PtNode, st: SymbolTable): PtIdentifier {
-    val target = st.lookup(name)
-    if(target?.astNode?.definingBlock()?.noSymbolPrefixing==true)
+    var target = st.lookup(name)
+    if(target?.astNode?.definingBlock()?.options?.noSymbolPrefixing==true)
         return this
 
-    val newName = name.split('.').map { "p8_$it" }.joinToString(".")
+    if(target==null) {
+        if(name.endsWith("_lsb") || name.endsWith("_msb")) {
+            target = st.lookup(name.dropLast(4))
+            if(target?.astNode?.definingBlock()?.options?.noSymbolPrefixing==true)
+                return this
+        }
+    }
+
+    val prefixType = when(target!!.type) {
+        StNodeType.BLOCK -> 'b'
+        StNodeType.SUBROUTINE, StNodeType.ROMSUB -> 's'
+        StNodeType.LABEL -> 'l'
+        StNodeType.STATICVAR, StNodeType.MEMVAR -> 'v'
+        StNodeType.CONSTANT -> 'c'
+        StNodeType.BUILTINFUNC -> 's'
+        StNodeType.MEMORYSLAB -> 'v'
+        else -> '?'
+    }
+    val newName = prefixScopedName(name, prefixType)
     val node = PtIdentifier(newName, type, position)
     node.parent = parent
     return node
@@ -201,19 +224,19 @@ class AsmGen6502Internal (
     internal val loopEndLabels = ArrayDeque<String>()
     private val zeropage = options.compTarget.machine.zeropage
     private val allocator = VariableAllocator(symbolTable, options, errors)
-    private val assemblyLines = mutableListOf<String>()
+    private val assembly = mutableListOf<String>()
     private val breakpointLabels = mutableListOf<String>()
-    private val forloopsAsmGen = ForLoopsAsmGen(program, this, zeropage)
+    private val forloopsAsmGen = ForLoopsAsmGen(this, zeropage)
     private val postincrdecrAsmGen = PostIncrDecrAsmGen(program, this)
     private val functioncallAsmGen = FunctionCallAsmGen(program, this)
     private val programGen = ProgramAndVarsGen(program, options, errors, symbolTable, functioncallAsmGen, this, allocator, zeropage)
-    private val assignmentAsmGen = AssignmentAsmGen(program, symbolTable, this, allocator)
-    private val expressionsAsmGen = ExpressionsAsmGen(program, this, allocator)
+    private val anyExprGen = AnyExprAsmGen(this)
+    private val assignmentAsmGen = AssignmentAsmGen(program, this, anyExprGen, allocator)
     private val builtinFunctionsAsmGen = BuiltinFunctionsAsmGen(program, this, assignmentAsmGen)
 
     fun compileToAssembly(): IAssemblyProgram? {
 
-        assemblyLines.clear()
+        assembly.clear()
         loopEndLabels.clear()
 
         println("Generating assembly code... ")
@@ -221,15 +244,22 @@ class AsmGen6502Internal (
 
         if(errors.noErrors()) {
             val output = options.outputDir.resolve("${program.name}.asm")
+            val asmLines = assembly.asSequence().flatMapTo(mutableListOf()) { it.split('\n') }
+            if(options.compTarget.name==Cx16Target.NAME) {
+                scanInvalid65816instructions(asmLines)
+                if(!errors.noErrors()) {
+                    errors.report()
+                    return null
+                }
+            }
             if(options.optimize) {
-                val separateLines = assemblyLines.flatMapTo(mutableListOf()) { it.split('\n') }
-                assemblyLines.clear()
-                while(optimizeAssembly(separateLines, options.compTarget.machine, symbolTable)>0) {
+                while(optimizeAssembly(asmLines, options.compTarget.machine, symbolTable)>0) {
                     // optimize the assembly source code
                 }
-                output.writeLines(separateLines)
+                output.writeLines(asmLines)
             } else {
-                output.writeLines(assemblyLines)
+                // write the unmodified code
+                output.writeLines(assembly)
             }
             return AssemblyProgram(program.name, options.outputDir, options.compTarget)
         } else {
@@ -238,10 +268,37 @@ class AsmGen6502Internal (
         }
     }
 
+    private fun scanInvalid65816instructions(asmLines: MutableList<String>) {
+        // The CommanderX16 ships with a WDC 65C02 CPU or a WDC 65816 CPU
+        // The latter is compatible with the 65C02 except for 4 instructions: RMB, SMB, BBS, BBR.
+        // We cannot set a different 6502 CPU target for the 64tass assembler, because we still need to support the STP and WAI instructions...
+        // so we have to scan for these instructions ourselves.
+        val invalid = Regex("""\s*((rmb\s|smb\s|bbs\s|bbr\s)|(rmb[0-7]|smb[0-7]|bbs[0-7]|bbr[0-7]))""", RegexOption.IGNORE_CASE)
+        for((index, line) in asmLines.withIndex()) {
+            if(line.length>=4 && invalid.matchesAt(line, 0)) {
+                errors.err(
+                    "invalid assembly instruction used (not compatible with the 65816 CPU): ${line.trim()}",
+                    Position("<output-assemblycode>", index, 1, 1)
+                )
+            }
+        }
+    }
+
     internal fun isTargetCpu(cpu: CpuType) = options.compTarget.machine.cpu == cpu
 
+    private var lastSourceLineNumber: Int = -1
+
     internal fun outputSourceLine(node: PtNode) {
-        out(" ;\tsrc line: ${node.position.file}:${node.position.line}")
+        if(!options.includeSourcelines || node.position===Position.DUMMY || node.position.line==lastSourceLineNumber)
+            return
+
+        lastSourceLineNumber = node.position.line
+        val srcComment = "\t; source: ${node.position.file}:${node.position.line}"
+        val line = SourceLineCache.retrieveLine(node.position)
+        if(line==null)
+            out(srcComment, false)
+        else
+            out("$srcComment   $line", false)
     }
 
     internal fun out(str: String, splitlines: Boolean = true) {
@@ -250,9 +307,9 @@ class AsmGen6502Internal (
             for (line in fragment.splitToSequence('\n')) {
                 val trimmed = if (line.startsWith(' ')) "\t" + line.trim() else line
                 // trimmed = trimmed.replace(Regex("^\\+\\s+"), "+\t")  // sanitize local label indentation
-                assemblyLines.add(trimmed)
+                assembly.add(trimmed)
             }
-        } else assemblyLines.add(fragment)
+        } else assembly.add(fragment)
     }
 
     fun asmSymbolName(regs: RegisterOrPair): String =
@@ -287,15 +344,32 @@ class AsmGen6502Internal (
             name
     }
 
+    fun asmVariableName(st: StNode, scope: PtSub?): String {
+        val name = asmVariableName(st.scopedName)
+        if(scope==null)
+            return name
+        // remove the whole prefix and just make the variable name locally scoped (64tass scopes it to the proper .proc block)
+        val subName = scope.scopedName
+        return if (name.length>subName.length && name.startsWith(subName) && name[subName.length] == '.')
+            name.drop(subName.length+1)
+        else
+            name
+    }
+
+
+    internal val tempVarsCounters = mutableMapOf(
+        DataType.BYTE to 0,
+        DataType.UBYTE to 0,
+        DataType.WORD to 0,
+        DataType.UWORD to 0,
+        DataType.FLOAT to 0
+    )
+
+    internal fun buildTempVarName(dt: DataType, counter: Int): String = "prog8_tmpvar_${dt.toString().lowercase()}_$counter"
+
     internal fun getTempVarName(dt: DataType): String {
-        return when(dt) {
-            DataType.UBYTE -> "cx16.r9L"
-            DataType.BYTE -> "cx16.r9sL"
-            DataType.UWORD -> "cx16.r9"
-            DataType.WORD -> "cx16.r9s"
-            DataType.FLOAT -> "floats.floats_temp_var"
-            else -> throw AssemblyError("invalid dt $dt")
-        }
+        tempVarsCounters[dt] = tempVarsCounters.getValue(dt)+1
+        return buildTempVarName(dt, tempVarsCounters.getValue(dt))
     }
 
     internal fun loadByteFromPointerIntoA(pointervar: PtIdentifier): String {
@@ -394,32 +468,6 @@ class AsmGen6502Internal (
         return name2.replace("prog8_lib.P8ZP_SCRATCH_", "P8ZP_SCRATCH_")    // take care of the 'hooks' to the temp vars -> reference zp symbols directly
     }
 
-    internal fun saveRegisterLocal(register: CpuRegister, scope: IPtSubroutine) {
-        if (isTargetCpu(CpuType.CPU65c02)) {
-            // just use the cpu's stack for all registers, shorter code
-            when (register) {
-                CpuRegister.A -> out("  pha")
-                CpuRegister.X -> out("  phx")
-                CpuRegister.Y -> out("  phy")
-            }
-        } else {
-            when (register) {
-                CpuRegister.A -> {
-                    // just use the stack, only for A
-                    out("  pha")
-                }
-                CpuRegister.X -> {
-                    out("  stx  prog8_regsaveX")
-                    subroutineExtra(scope).usedRegsaveX = true
-                }
-                CpuRegister.Y -> {
-                    out("  sty  prog8_regsaveY")
-                    subroutineExtra(scope).usedRegsaveY = true
-                }
-            }
-        }
-    }
-
     internal fun saveRegisterStack(register: CpuRegister, keepA: Boolean) {
         when (register) {
             CpuRegister.A -> out("  pha")
@@ -444,24 +492,6 @@ class AsmGen6502Internal (
         }
     }
 
-    internal fun restoreRegisterLocal(register: CpuRegister) {
-        if (isTargetCpu(CpuType.CPU65c02)) {
-            when (register) {
-                // this just used the stack, for all registers. Shorter code.
-                CpuRegister.A -> out("  pla")
-                CpuRegister.X -> out("  plx")
-                CpuRegister.Y -> out("  ply")
-            }
-
-        } else {
-            when (register) {
-                CpuRegister.A -> out("  pla")   // this just used the stack but only for A
-                CpuRegister.X -> out("  ldx  prog8_regsaveX")
-                CpuRegister.Y -> out("  ldy  prog8_regsaveY")
-            }
-        }
-    }
-
     internal fun restoreRegisterStack(register: CpuRegister, keepA: Boolean) {
         when (register) {
             CpuRegister.A -> {
@@ -522,40 +552,30 @@ class AsmGen6502Internal (
         }
     }
 
-    internal fun loadScaledArrayIndexIntoRegister(
-        expr: PtArrayIndexer,
-        elementDt: DataType,
-        register: CpuRegister
-    ) {
+    internal fun loadScaledArrayIndexIntoRegister(expr: PtArrayIndexer, register: CpuRegister) {
         val reg = register.toString().lowercase()
         val indexnum = expr.index.asConstInteger()
         if (indexnum != null) {
             val indexValue = if(expr.splitWords)
                 indexnum
             else
-                indexnum * options.compTarget.memorySize(elementDt)
+                indexnum * options.compTarget.memorySize(expr.type)
             out("  ld$reg  #$indexValue")
             return
         }
 
-        val indexVar = expr.index as? PtIdentifier
-            ?: throw AssemblyError("array indexer should have been replaced with a temp var @ ${expr.index.position}")
-
-        val indexName = asmVariableName(indexVar)
-
         if(expr.splitWords) {
-            when (register) {
-                CpuRegister.A -> out("  lda  $indexName")
-                CpuRegister.X -> out("  ldx  $indexName")
-                CpuRegister.Y -> out("  ldy  $indexName")
-            }
+            assignExpressionToRegister(expr.index, RegisterOrPair.fromCpuRegister(register), false)
             return
         }
 
-        when (elementDt) {
-            in ByteDatatypes -> out("  ld$reg  $indexName")
+        when (expr.type) {
+            in ByteDatatypes -> {
+                assignExpressionToRegister(expr.index, RegisterOrPair.fromCpuRegister(register), false)
+            }
             in WordDatatypes -> {
-                out("  lda  $indexName |  asl  a")
+                assignExpressionToRegister(expr.index, RegisterOrPair.A, false)
+                out("  asl  a")
                 when (register) {
                     CpuRegister.A -> {}
                     CpuRegister.X -> out(" tax")
@@ -564,12 +584,13 @@ class AsmGen6502Internal (
             }
             DataType.FLOAT -> {
                 require(options.compTarget.memorySize(DataType.FLOAT) == 5) {"invalid float size ${expr.position}"}
+                assignExpressionToRegister(expr.index, RegisterOrPair.A, false)
                 out("""
-                    lda  $indexName
+                    sta  P8ZP_SCRATCH_REG
                     asl  a
                     asl  a
                     clc
-                    adc  $indexName"""
+                    adc  P8ZP_SCRATCH_REG"""
                 )
                 when (register) {
                     CpuRegister.A -> {}
@@ -581,22 +602,12 @@ class AsmGen6502Internal (
         }
     }
 
-    @Deprecated("avoid calling this as it generates slow evalstack based code")
-    internal fun translateExpression(expression: PtExpression) =
-            expressionsAsmGen.translateExpression(expression)
-
-    internal fun translateBuiltinFunctionCallExpression(bfc: PtBuiltinFunctionCall, resultToStack: Boolean, resultRegister: RegisterOrPair?): DataType? =
-            builtinFunctionsAsmGen.translateFunctioncallExpression(bfc, resultToStack, resultRegister)
+    internal fun translateBuiltinFunctionCallExpression(bfc: PtBuiltinFunctionCall, resultRegister: RegisterOrPair?): DataType? =
+            builtinFunctionsAsmGen.translateFunctioncallExpression(bfc, resultRegister)
 
     internal fun translateFunctionCall(functionCallExpr: PtFunctionCall) =
             functioncallAsmGen.translateFunctionCall(functionCallExpr)
 
-    internal fun saveXbeforeCall(functionCall: PtFunctionCall)  =
-            functioncallAsmGen.saveXbeforeCall(functionCall)
-
-    internal fun restoreXafterCall(functionCall: PtFunctionCall) =
-            functioncallAsmGen.restoreXafterCall(functionCall)
-
     internal fun translateNormalAssignment(assign: AsmAssignment, scope: IPtSubroutine?) =
             assignmentAsmGen.translateNormalAssignment(assign, scope)
 
@@ -613,7 +624,7 @@ class AsmGen6502Internal (
         when(reg) {
             RegisterOrPair.A,
             RegisterOrPair.X,
-            RegisterOrPair.Y -> assignmentAsmGen.assignRegisterByte(target, reg.asCpuRegister(), target.datatype in SignedDatatypes)
+            RegisterOrPair.Y -> assignmentAsmGen.assignRegisterByte(target, reg.asCpuRegister(), target.datatype in SignedDatatypes, true)
             RegisterOrPair.AX,
             RegisterOrPair.AY,
             RegisterOrPair.XY,
@@ -625,9 +636,36 @@ class AsmGen6502Internal (
     }
 
     internal fun assignExpressionTo(value: PtExpression, target: AsmAssignTarget) {
-        // don't use translateExpression() to avoid evalstack
         when (target.datatype) {
             in ByteDatatypes -> {
+                if (value.asConstInteger()==0) {
+                    when(target.kind) {
+                        TargetStorageKind.VARIABLE -> {
+                            if (isTargetCpu(CpuType.CPU6502))
+                                out("lda  #0 |  sta  ${target.asmVarname}")
+                            else
+                                out("stz  ${target.asmVarname}")
+                        }
+                        TargetStorageKind.MEMORY -> {
+                            val address = target.memory!!.address.asConstInteger()
+                            if(address!=null) {
+                                if (isTargetCpu(CpuType.CPU6502))
+                                    out("lda  #0 |  sta  ${address.toHex()}")
+                                else
+                                    out("  stz  ${address.toHex()}")
+                                return
+                            }
+                        }
+                        TargetStorageKind.REGISTER -> {
+                            val zero = PtNumber(DataType.UBYTE, 0.0, value.position)
+                            zero.parent = value
+                            assignExpressionToRegister(zero, target.register!!, false)
+                            return
+                        }
+                        else -> { }
+                    }
+                }
+
                 assignExpressionToRegister(value, RegisterOrPair.A)
                 assignRegister(RegisterOrPair.A, target)
             }
@@ -707,7 +745,6 @@ class AsmGen6502Internal (
                 if (jump is PtJump) {
                     // jump somewhere if X!=0
                     val label = when {
-                        jump.generatedLabel!=null -> jump.generatedLabel!!
                         jump.identifier!=null -> asmSymbolName(jump.identifier!!)
                         jump.address!=null -> jump.address!!.toHex()
                         else -> throw AssemblyError("weird jump")
@@ -907,7 +944,7 @@ $repeatLabel""")
             DataType.UBYTE, DataType.UWORD -> {
                 val result = zeropage.allocate(counterVar, dt, null, stmt.position, errors)
                 result.fold(
-                    success = { (address, _) -> asmInfo.extraVars.add(Triple(dt, counterVar, address)) },
+                    success = { (address, _, _) -> asmInfo.extraVars.add(Triple(dt, counterVar, address)) },
                     failure = { asmInfo.extraVars.add(Triple(dt, counterVar, null)) }  // allocate normally
                 )
                 return counterVar
@@ -1007,7 +1044,6 @@ $repeatLabel""")
 
     private fun getJumpTarget(jump: PtJump): Pair<String, Boolean> {
         val ident = jump.identifier
-        val label = jump.generatedLabel
         val addr = jump.address
         return when {
             ident!=null -> {
@@ -1018,7 +1054,6 @@ $repeatLabel""")
                 else
                     Pair(asmSymbolName(ident), false)
             }
-            label!=null -> Pair(label, false)
             addr!=null -> Pair(addr.toHex(), false)
             else -> Pair("????", false)
         }
@@ -1047,7 +1082,10 @@ $repeatLabel""")
     }
 
     private fun translate(asm: PtInlineAssembly) {
-        assemblyLines.add(asm.assembly.trimEnd().trimStart('\r', '\n'))
+        if(asm.isIR)
+            throw AssemblyError("%asm containing IR code cannot be translated to 6502 assembly")
+        else
+            assembly.add(asm.assembly.trimEnd().trimStart('\r', '\n'))
     }
 
     private fun translate(incbin: PtIncludeBinary) {
@@ -1069,6 +1107,9 @@ $repeatLabel""")
         val label = "_prog8_breakpoint_${breakpointLabels.size+1}"
         breakpointLabels.add(label)
         out(label)
+        if(options.breakpointCpuInstruction!=null) {
+            out("  ${options.breakpointCpuInstruction}")
+        }
     }
 
     internal fun signExtendAYlsb(valueDt: DataType) {
@@ -1086,20 +1127,6 @@ $repeatLabel""")
         }
     }
 
-    internal fun signExtendStackLsb(valueDt: DataType) {
-        // sign extend signed byte on stack to signed word on stack
-        when(valueDt) {
-            DataType.UBYTE -> {
-                if(isTargetCpu(CpuType.CPU65c02))
-                    out("  stz  P8ESTACK_HI+1,x")
-                else
-                    out("  lda  #0 |  sta  P8ESTACK_HI+1,x")
-            }
-            DataType.BYTE -> out("  jsr  prog8_lib.sign_extend_stack_byte")
-            else -> throw AssemblyError("need byte type")
-        }
-    }
-
     internal fun signExtendVariableLsb(asmvar: String, valueDt: DataType) {
         // sign extend signed byte in a var to a full word in that variable
         when(valueDt) {
@@ -1165,7 +1192,7 @@ $repeatLabel""")
         return null
     }
 
-    internal fun tryOptimizedPointerAccessWithA(addressExpr: PtExpression, operator: String, write: Boolean): Boolean {
+    internal fun tryOptimizedPointerAccessWithA(addressExpr: PtBinaryExpression, write: Boolean): Boolean {
         // optimize pointer,indexregister if possible
 
         fun evalBytevalueWillClobberA(expr: PtExpression): Boolean {
@@ -1181,7 +1208,7 @@ $repeatLabel""")
             }
         }
 
-        if(operator=="+") {
+        if(addressExpr.operator=="+") {
             val ptrAndIndex = pointerViaIndexRegisterPossible(addressExpr)
             if(ptrAndIndex!=null) {
                 val pointervar = ptrAndIndex.first as? PtIdentifier
@@ -1270,7 +1297,6 @@ $repeatLabel""")
         val rightConstVal = right as? PtNumber
 
         val label = when {
-            jump.generatedLabel!=null -> jump.generatedLabel!!
             jump.identifier!=null -> asmSymbolName(jump.identifier!!)
             jump.address!=null -> jump.address!!.toHex()
             else -> throw AssemblyError("weird jump")
@@ -1728,7 +1754,7 @@ $repeatLabel""")
                 }
                 else if (left is PtMemoryByte) {
                     return if(rightConstVal.number.toInt()!=0) {
-                        translateDirectMemReadExpressionToRegAorStack(left, false)
+                        translateDirectMemReadExpressionToRegA(left)
                         code("#${rightConstVal.number.toInt()}")
                     }
                     else
@@ -1875,7 +1901,7 @@ $repeatLabel""")
                         out("  beq $jumpIfFalseLabel")
                 }
                 else if (left is PtMemoryByte) {
-                    translateDirectMemReadExpressionToRegAorStack(left, false)
+                    translateDirectMemReadExpressionToRegA(left)
                     return if(rightConstVal.number.toInt()!=0)
                         code("#${rightConstVal.number.toInt()}")
                     else
@@ -2036,7 +2062,7 @@ $repeatLabel""")
                         out("  bne  $jumpIfFalseLabel")
                 }
                 else if (left is PtMemoryByte) {
-                    translateDirectMemReadExpressionToRegAorStack(left, false)
+                    translateDirectMemReadExpressionToRegA(left)
                     return if(rightConstVal.number.toInt()!=0)
                         code("#${rightConstVal.number.toInt()}")
                     else
@@ -2200,7 +2226,7 @@ $repeatLabel""")
                 }
                 else if (left is PtMemoryByte) {
                     if(rightConstVal.number.toInt()!=0) {
-                        translateDirectMemReadExpressionToRegAorStack(left, false)
+                        translateDirectMemReadExpressionToRegA(left)
                         code("#${rightConstVal.number.toInt()}")
                     }
                     return
@@ -2363,7 +2389,7 @@ $repeatLabel""")
                         out("  bne  $jumpIfFalseLabel")
                 }
                 else if (left is PtMemoryByte) {
-                    translateDirectMemReadExpressionToRegAorStack(left, false)
+                    translateDirectMemReadExpressionToRegA(left)
                     return if(rightConstVal.number.toInt()!=0)
                         code("#${rightConstVal.number.toInt()}")
                     else
@@ -2409,7 +2435,7 @@ $repeatLabel""")
                         out("  beq  $jumpIfFalseLabel")
                 }
                 else if (left is PtMemoryByte) {
-                    translateDirectMemReadExpressionToRegAorStack(left, false)
+                    translateDirectMemReadExpressionToRegA(left)
                     return if(rightConstVal.number.toInt()!=0)
                         code("#${rightConstVal.number.toInt()}")
                     else
@@ -2474,8 +2500,7 @@ $repeatLabel""")
                     cmp  #<$number
                     bne  $jumpIfFalseLabel
                     cpy  #>$number
-                    bne  $jumpIfFalseLabel
-                    """)
+                    bne  $jumpIfFalseLabel""")
             }
             is PtIdentifier -> {
                 assignExpressionToRegister(left, RegisterOrPair.AY)
@@ -2483,18 +2508,21 @@ $repeatLabel""")
                     cmp  ${asmVariableName(right)}
                     bne  $jumpIfFalseLabel
                     cpy  ${asmVariableName(right)}+1
-                    bne  $jumpIfFalseLabel
-                    """)
+                    bne  $jumpIfFalseLabel""")
             }
             is PtAddressOf -> {
                 assignExpressionToRegister(left, RegisterOrPair.AY)
                 val name = asmSymbolName(right.identifier)
-                out("""
-                    cmp  #<$name
-                    bne  $jumpIfFalseLabel
-                    cpy  #>$name
-                    bne  $jumpIfFalseLabel
-                    """)
+                if(right.isFromArrayElement) {
+                    TODO("address-of array element $name at ${right.position}")
+                    // assignmentAsmGen.assignAddressOf(target, name, right.arrayIndexExpr)
+                } else {
+                    out("""
+                        cmp  #<$name
+                        bne  $jumpIfFalseLabel
+                        cpy  #>$name
+                        bne  $jumpIfFalseLabel""")
+                }
             }
             else -> {
                 if(left.isSimple()) {
@@ -2575,12 +2603,16 @@ $repeatLabel""")
             is PtAddressOf -> {
                 assignExpressionToRegister(left, RegisterOrPair.AY)
                 val name = asmSymbolName(right.identifier)
-                out("""
-                    cmp  #<$name
-                    bne  +
-                    cpy  #>$name
-                    beq  $jumpIfFalseLabel
-+""")
+                if(right.isFromArrayElement) {
+                    TODO("address-of array element $name at ${right.position}")
+                } else {
+                    out("""
+                        cmp  #<$name
+                        bne  +
+                        cpy  #>$name
+                        beq  $jumpIfFalseLabel
+    +""")
+                }
             }
             else -> {
                 if(left.isSimple()) {
@@ -2865,22 +2897,14 @@ $repeatLabel""")
 +""")
     }
 
-    internal fun translateDirectMemReadExpressionToRegAorStack(expr: PtMemoryByte, pushResultOnEstack: Boolean) {
+    internal fun translateDirectMemReadExpressionToRegA(expr: PtMemoryByte) {
 
         fun assignViaExprEval() {
             assignExpressionToVariable(expr.address, "P8ZP_SCRATCH_W2", DataType.UWORD)
             if (isTargetCpu(CpuType.CPU65c02)) {
-                if (pushResultOnEstack) {
-                    out("  lda  (P8ZP_SCRATCH_W2) |  dex |  sta  P8ESTACK_LO+1,x")
-                } else {
-                    out("  lda  (P8ZP_SCRATCH_W2)")
-                }
+                out("  lda  (P8ZP_SCRATCH_W2)")
             } else {
-                if (pushResultOnEstack) {
-                    out("  ldy  #0 |  lda  (P8ZP_SCRATCH_W2),y |  dex |  sta  P8ESTACK_LO+1,x")
-                } else {
-                    out("  ldy  #0 |  lda  (P8ZP_SCRATCH_W2),y")
-                }
+                out("  ldy  #0 |  lda  (P8ZP_SCRATCH_W2),y")
             }
         }
 
@@ -2888,21 +2912,14 @@ $repeatLabel""")
             is PtNumber -> {
                 val address = (expr.address as PtNumber).number.toInt()
                 out("  lda  ${address.toHex()}")
-                if(pushResultOnEstack)
-                    out("  sta  P8ESTACK_LO,x |  dex")
             }
             is PtIdentifier -> {
                 // the identifier is a pointer variable, so read the value from the address in it
                 loadByteFromPointerIntoA(expr.address as PtIdentifier)
-                if(pushResultOnEstack)
-                    out("  sta  P8ESTACK_LO,x |  dex")
             }
             is PtBinaryExpression -> {
                 val addrExpr = expr.address as PtBinaryExpression
-                if(tryOptimizedPointerAccessWithA(addrExpr, addrExpr.operator, false)) {
-                    if(pushResultOnEstack)
-                        out("  sta  P8ESTACK_LO,x |  dex")
-                } else {
+                if(!tryOptimizedPointerAccessWithA(addrExpr, false)) {
                     assignViaExprEval()
                 }
             }
@@ -2921,8 +2938,12 @@ $repeatLabel""")
             is PtAddressOf -> {
                 assignExpressionToRegister(right, RegisterOrPair.AY)
                 val name = asmSymbolName(left.identifier)
-                code("#>$name", "#<$name")
-                return true
+                if(left.isFromArrayElement) {
+                    TODO("address-of array element $name at ${left.position}")
+                } else {
+                    code("#>$name", "#<$name")
+                    return true
+                }
             }
             is PtIdentifier -> {
                 assignExpressionToRegister(right, RegisterOrPair.AY)
@@ -2970,8 +2991,12 @@ $repeatLabel""")
             is PtAddressOf -> {
                 assignExpressionToRegister(left, RegisterOrPair.AY)
                 val name = asmSymbolName(right.identifier)
-                code("#>$name", "#<$name")
-                return true
+                if(right.isFromArrayElement) {
+                    TODO("address-of array element $name at ${right.position}")
+                } else {
+                    code("#>$name", "#<$name")
+                    return true
+                }
             }
             is PtIdentifier -> {
                 assignExpressionToRegister(left, RegisterOrPair.AY)
@@ -3055,30 +3080,16 @@ $repeatLabel""")
         }
     }
 
-    internal fun popCpuStack(dt: DataType, target: IPtVariable, scope: IPtSubroutine?) {
-        // note: because A is pushed first so popped last, saving A is often not required here.
-        val targetAsmSub = (target as PtNode).definingAsmSub()
-        if(targetAsmSub != null) {
-            val parameter = targetAsmSub.parameters.first { it.second.name==target.name }
-            popCpuStack(targetAsmSub, parameter.second, parameter.first)
-            return
-        }
-        val scopedName = when(target) {
-            is PtConstant -> target.scopedName
-            is PtMemMapped -> target.scopedName
-            is PtVariable -> target.scopedName
-            else -> throw AssemblyError("weird target var")
-        }
-        val tgt = AsmAssignTarget(TargetStorageKind.VARIABLE, this, target.type, scope, target.position, variableAsmName = asmVariableName(scopedName))
+    internal fun popCpuStack(dt: DataType) {
         if (dt in ByteDatatypes) {
             out("  pla")
-            assignRegister(RegisterOrPair.A, tgt)
-        } else {
+        } else if (dt in WordDatatypes) {
             if (isTargetCpu(CpuType.CPU65c02))
                 out("  ply |  pla")
             else
                 out("  pla |  tay |  pla")
-            assignRegister(RegisterOrPair.AY, tgt)
+        } else {
+            throw AssemblyError("can't pop type $dt")
         }
     }
 
@@ -3098,6 +3109,18 @@ $repeatLabel""")
         }
     }
 
+    internal fun pushFAC1() {
+        out("  jsr  floats.pushFAC1")
+    }
+
+    internal fun popFAC1() {
+        out("  clc |  jsr  floats.popFAC")
+    }
+
+    internal fun popFAC2() {
+        out("  sec |  jsr  floats.popFAC")
+    }
+
     internal fun needAsaveForExpr(arg: PtExpression): Boolean =
         arg !is PtNumber && arg !is PtIdentifier && (arg !is PtMemoryByte || !arg.isSimple())
 
@@ -3118,9 +3141,20 @@ $repeatLabel""")
 
     internal fun makeLabel(postfix: String): String {
         generatedLabelSequenceNumber++
-        return "prog8_label_asm_${generatedLabelSequenceNumber}_$postfix"
+        return "label_asm_${generatedLabelSequenceNumber}_$postfix"
     }
 
+    fun assignConstFloatToPointerAY(number: PtNumber) {
+        val floatConst = allocator.getFloatAsmConst(number.number)
+        out("""
+            pha
+            lda  #<$floatConst
+            sta  P8ZP_SCRATCH_W1
+            lda  #>$floatConst
+            sta  P8ZP_SCRATCH_W1+1
+            pla
+            jsr  floats.copy_float""")
+    }
 }
 
 /**
@@ -3130,9 +3164,6 @@ $repeatLabel""")
  * it's more consistent to only define these attributes on a Subroutine node.
  */
 internal class SubroutineExtraAsmInfo {
-    var usedRegsaveA = false
-    var usedRegsaveX = false
-    var usedRegsaveY = false
     var usedFloatEvalResultVar1 = false
     var usedFloatEvalResultVar2 = false
 

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

@@ -15,21 +15,7 @@ internal fun optimizeAssembly(lines: MutableList<String>, machine: IMachineDefin
 
     var linesByFour = getLinesBy(lines, 4)
 
-    var mods = optimizeUselessStackByteWrites(linesByFour)
-    if(mods.isNotEmpty()) {
-        apply(mods, lines)
-        linesByFour = getLinesBy(lines, 4)
-        numberOfOptimizations++
-    }
-
-    mods = optimizeIncDec(linesByFour)
-    if(mods.isNotEmpty()) {
-        apply(mods, lines)
-        linesByFour = getLinesBy(lines, 4)
-        numberOfOptimizations++
-    }
-
-    mods = optimizeCmpSequence(linesByFour)
+    var mods = optimizeIncDec(linesByFour)
     if(mods.isNotEmpty()) {
         apply(mods, lines)
         linesByFour = getLinesBy(lines, 4)
@@ -57,6 +43,13 @@ internal fun optimizeAssembly(lines: MutableList<String>, machine: IMachineDefin
         numberOfOptimizations++
     }
 
+    mods = optimizeUnneededTempvarInAdd(linesByFour)
+    if(mods.isNotEmpty()) {
+        apply(mods, lines)
+        linesByFour = getLinesBy(lines, 4)
+        numberOfOptimizations++
+    }
+
     var linesByFourteen = getLinesBy(lines, 14)
     mods = optimizeSameAssignments(linesByFourteen, machine, symbolTable)
     if(mods.isNotEmpty()) {
@@ -97,44 +90,6 @@ private fun getLinesBy(lines: MutableList<String>, windowSize: Int) =
 // all lines (that aren't empty or comments) in sliding windows of certain size
         lines.withIndex().filter { it.value.isNotBlank() && !it.value.trimStart().startsWith(';') }.windowed(windowSize, partialWindows = false)
 
-private fun optimizeCmpSequence(linesByFour: List<List<IndexedValue<String>>>): List<Modification> {
-    // when statement (on bytes) generates a sequence of:
-    //	 lda  $ce01,x
-    //	 cmp  #$20
-    //	 beq  check_prog8_s72choice_32
-    //	 lda  $ce01,x
-    //	 cmp  #$21
-    //	 beq  check_prog8_s73choice_33
-    // the repeated lda can be removed
-    val mods = mutableListOf<Modification>()
-    for(lines in linesByFour) {
-        if(lines[0].value.trim()=="lda  P8ESTACK_LO+1,x" &&
-                lines[1].value.trim().startsWith("cmp ") &&
-                lines[2].value.trim().startsWith("beq ") &&
-                lines[3].value.trim()=="lda  P8ESTACK_LO+1,x") {
-            mods.add(Modification(lines[3].index, true, null)) // remove the second lda
-        }
-    }
-    return mods
-}
-
-private fun optimizeUselessStackByteWrites(linesByFour: List<List<IndexedValue<String>>>): List<Modification> {
-    // sta on stack, dex, inx, lda from stack -> eliminate this useless stack byte write
-    // this is a lot harder for word values because the instruction sequence varies.
-    val mods = mutableListOf<Modification>()
-    for(lines in linesByFour) {
-        if(lines[0].value.trim()=="sta  P8ESTACK_LO,x" &&
-                lines[1].value.trim()=="dex" &&
-                lines[2].value.trim()=="inx" &&
-                lines[3].value.trim()=="lda  P8ESTACK_LO,x") {
-            mods.add(Modification(lines[1].index, true, null))
-            mods.add(Modification(lines[2].index, true, null))
-            mods.add(Modification(lines[3].index, true, null))
-        }
-    }
-    return mods
-}
-
 private fun optimizeSameAssignments(
     linesByFourteen: List<List<IndexedValue<String>>>,
     machine: IMachineDefinition,
@@ -426,15 +381,9 @@ private fun optimizeStoreLoadSame(
         } else if(first=="phx" && second=="pla") {
             mods.add(Modification(lines[1].index, true, null))
             mods.add(Modification(lines[2].index, false, "  txa"))
-        } else if(first=="phx" && second=="ply") {
-            mods.add(Modification(lines[1].index, true, null))
-            mods.add(Modification(lines[2].index, false, "  txy"))
         } else if(first=="phy" && second=="pla") {
             mods.add(Modification(lines[1].index, true, null))
             mods.add(Modification(lines[2].index, false, "  tya"))
-        } else if(first=="phy" && second=="plx") {
-            mods.add(Modification(lines[1].index, true, null))
-            mods.add(Modification(lines[2].index, false, "  tyx"))
         }
     }
     return mods
@@ -560,4 +509,27 @@ private fun optimizeUselessPushPopStack(linesByFour: List<List<IndexedValue<Stri
         optimize('y', lines)
     }
     return mods
-}
+}
+
+private fun optimizeUnneededTempvarInAdd(linesByFour: List<List<IndexedValue<String>>>): List<Modification> {
+    // sequence:  sta  P8ZP_SCRATCH_XX  / lda  something / clc / adc  P8ZP_SCRATCH_XX
+    // this can be performed without the scratch variable:  clc  /  adc  something
+    val mods = mutableListOf<Modification>()
+
+    for(lines in linesByFour) {
+        val first = lines[0].value.trimStart()
+        val second = lines[1].value.trimStart()
+        val third = lines[2].value.trimStart()
+        val fourth = lines[3].value.trimStart()
+        if(first.startsWith("sta  P8ZP_SCRATCH_") && second.startsWith("lda") && third.startsWith("clc") && fourth.startsWith("adc  P8ZP_SCRATCH_") ) {
+            if(fourth.substring(4)==first.substring(4)) {
+                mods.add(Modification(lines[0].index, false, "    clc"))
+                mods.add(Modification(lines[1].index, false, "    adc  ${second.substring(3).trimStart()}"))
+                mods.add(Modification(lines[2].index, true, null))
+                mods.add(Modification(lines[3].index, true, null))
+            }
+        }
+    }
+
+    return mods
+}

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

@@ -1,9 +1,8 @@
 package prog8.codegen.cpu6502
 
-import prog8.code.ast.*
+import prog8.code.ast.PtAsmSub
 import prog8.code.core.Cx16VirtualRegisters
 import prog8.code.core.RegisterOrPair
-import prog8.code.core.RegisterOrStatusflag
 
 
 fun asmsub6502ArgsEvalOrder(sub: PtAsmSub): List<Int> {
@@ -11,50 +10,19 @@ fun asmsub6502ArgsEvalOrder(sub: PtAsmSub): List<Int> {
     // order is:
     //  1) cx16 virtual word registers,
     //  2) paired CPU registers,
-    //  3) single CPU registers (X last), except A,
+    //  3) single CPU registers (order Y,X,A),
     //  4) CPU Carry status flag
-    //  5) the A register itself last   (so everything before it can use the accumulator without having to save its value)
     val args = sub.parameters.withIndex()
     val (cx16regs, args2) = args.partition { it.value.first.registerOrPair in Cx16VirtualRegisters }
     val pairedRegisters = arrayOf(RegisterOrPair.AX, RegisterOrPair.AY, RegisterOrPair.XY)
     val (pairedRegs , args3) = args2.partition { it.value.first.registerOrPair in pairedRegisters }
-    val (regsWithoutA, args4) = args3.partition { it.value.first.registerOrPair != RegisterOrPair.A }
-    val (regA, rest) = args4.partition { it.value.first.registerOrPair != null }
+    val (singleRegs, rest) = args3.partition { it.value.first.registerOrPair != null }
 
     cx16regs.forEach { order += it.index }
     pairedRegs.forEach { order += it.index }
-    regsWithoutA.forEach {
-        if(it.value.first.registerOrPair != RegisterOrPair.X)
-            order += it.index
-    }
-    regsWithoutA.firstOrNull { it.value.first.registerOrPair==RegisterOrPair.X } ?.let { order += it.index}
+    singleRegs.sortedBy { it.value.first.registerOrPair!!.asCpuRegister() }.asReversed().forEach { order += it.index }
+    require(rest.all { it.value.first.registerOrPair==null && it.value.first.statusflag!=null})
     rest.forEach { order += it.index }
-    regA.forEach { order += it.index }
     require(order.size==sub.parameters.size)
     return order
 }
-
-fun asmsub6502ArgsHaveRegisterClobberRisk(
-    args: List<PtExpression>,
-    params: List<Pair<RegisterOrStatusflag, PtSubroutineParameter>>
-): Boolean {
-    fun isClobberRisk(expr: PtExpression): Boolean {
-        when (expr) {
-            is PtArrayIndexer -> {
-                return params.any {
-                    it.first.registerOrPair in listOf(RegisterOrPair.Y, RegisterOrPair.AY, RegisterOrPair.XY)
-                }
-            }
-            is PtBuiltinFunctionCall -> {
-                if (expr.name == "lsb" || expr.name == "msb")
-                    return isClobberRisk(expr.args[0])
-                if (expr.name == "mkword")
-                    return isClobberRisk(expr.args[0]) && isClobberRisk(expr.args[1])
-                return !expr.isSimple()
-            }
-            else -> return !expr.isSimple()
-        }
-    }
-
-    return args.size>1 && args.any { isClobberRisk(it) }
-}

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

@@ -1,14 +1,8 @@
 package prog8.codegen.cpu6502
 
-import com.github.michaelbull.result.Ok
-import com.github.michaelbull.result.Result
-import com.github.michaelbull.result.mapError
 import prog8.code.core.*
 import prog8.code.target.C64Target
-import java.io.File
 import java.nio.file.Path
-import kotlin.io.path.Path
-import kotlin.io.path.isRegularFile
 
 
 internal class AssemblyProgram(
@@ -28,15 +22,20 @@ internal class AssemblyProgram(
         val assemblerCommand: List<String>
 
         when (compTarget.name) {
-            in setOf("c64", "c128", "cx16") -> {
+            in setOf("c64", "c128", "cx16", "pet32") -> {
                 // CBM machines .prg generation.
 
                 // add "-Wlong-branch"  to see warnings about conversion of branch instructions to jumps (default = do this silently)
                 val command = mutableListOf("64tass", "--ascii", "--case-sensitive", "--long-branch",
-                    "-Wall", "-Wno-strict-bool", "-Wno-shadow", // "-Werror",
+                    "-Wall", // "-Wno-strict-bool", "-Werror",
                     "--dump-labels", "--vice-labels", "--labels=$viceMonListFile", "--no-monitor"
                 )
 
+                if(options.warnSymbolShadowing)
+                    command.add("-Wshadow")
+                else
+                    command.add("-Wno-shadow")
+
                 if(options.asmQuiet)
                     command.add("--quiet")
 
@@ -65,10 +64,15 @@ internal class AssemblyProgram(
 
                 // TODO are these options okay for atari?
                 val command = mutableListOf("64tass", "--ascii", "--case-sensitive", "--long-branch",
-                    "-Wall", "-Wno-strict-bool", "-Wno-shadow", // "-Werror",
+                    "-Wall", // "-Werror", "-Wno-strict-bool"
                     "--no-monitor"
                 )
 
+                if(options.warnSymbolShadowing)
+                    command.add("-Wshadow")
+                else
+                    command.add("-Wno-shadow")
+
                 if(options.asmQuiet)
                     command.add("--quiet")
 
@@ -130,18 +134,3 @@ internal class AssemblyProgram(
         viceMonListFile.toFile().appendText(breakpoints.joinToString("\n") + "\n")
     }
 }
-
-
-internal fun loadAsmIncludeFile(filename: String, source: SourceCode): Result<String, NoSuchFileException> {
-    return if (filename.startsWith(SourceCode.libraryFilePrefix)) {
-        return com.github.michaelbull.result.runCatching {
-            SourceCode.Resource("/prog8lib/${filename.substring(SourceCode.libraryFilePrefix.length)}").text
-        }.mapError { NoSuchFileException(File(filename)) }
-    } else {
-        val sib = Path(source.origin).resolveSibling(filename)
-        if (sib.isRegularFile())
-            Ok(SourceCode.File(sib).text)
-        else
-            Ok(SourceCode.File(Path(filename)).text)
-    }
-}

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

@@ -1,933 +0,0 @@
-package prog8.codegen.cpu6502
-
-import prog8.code.ast.*
-import prog8.code.core.*
-import kotlin.math.absoluteValue
-
-internal class ExpressionsAsmGen(private val program: PtProgram,
-                                 private val asmgen: AsmGen6502Internal,
-                                 private val allocator: VariableAllocator) {
-
-    @Deprecated("avoid calling this as it generates slow evalstack based code")
-    internal fun translateExpression(expression: PtExpression) {
-        if (this.asmgen.options.slowCodegenWarnings) {
-            asmgen.errors.warn("slow stack evaluation used for expression", expression.position)
-        }
-        translateExpressionInternal(expression)
-    }
-
-
-    // the rest of the methods are all PRIVATE
-
-
-    private fun translateExpressionInternal(expression: PtExpression) {
-
-        when(expression) {
-            is PtPrefix -> translateExpression(expression)
-            is PtBinaryExpression -> translateExpression(expression)
-            is PtArrayIndexer -> translateExpression(expression)
-            is PtTypeCast -> translateExpression(expression)
-            is PtAddressOf -> translateExpression(expression)
-            is PtMemoryByte -> asmgen.translateDirectMemReadExpressionToRegAorStack(expression, true)
-            is PtNumber -> translateExpression(expression)
-            is PtIdentifier -> translateExpression(expression)
-            is PtFunctionCall -> translateFunctionCallResultOntoStack(expression)
-            is PtBuiltinFunctionCall -> asmgen.translateBuiltinFunctionCallExpression(expression, true, null)
-            is PtContainmentCheck -> translateContainmentCheck(expression)
-            is PtArray, is PtString -> throw AssemblyError("string/array literal value assignment should have been replaced by a variable")
-            is PtRange -> throw AssemblyError("range expression should have been changed into array values")
-            is PtMachineRegister -> throw AssemblyError("machine register ast node should not occur in 6502 codegen it is for IR code")
-            else -> TODO("missing expression asmgen for $expression")
-        }
-    }
-
-    private fun translateContainmentCheck(check: PtContainmentCheck) {
-        asmgen.assignExpressionToRegister(check, RegisterOrPair.A)
-        asmgen.out("  sta  P8ESTACK_LO,x |  dex")
-    }
-
-    private fun translateFunctionCallResultOntoStack(call: PtFunctionCall) {
-        // only for use in nested expression evaluation
-
-        val symbol = asmgen.symbolTable.lookup(call.name)
-        val sub = symbol!!.astNode as IPtSubroutine
-        asmgen.saveXbeforeCall(call)
-        asmgen.translateFunctionCall(call)
-        if(sub.regXasResult()) {
-            // store the return value in X somewhere that we can access again below
-            asmgen.out("  stx  P8ZP_SCRATCH_REG")
-        }
-        asmgen.restoreXafterCall(call)
-
-        val returns: List<Pair<RegisterOrStatusflag, DataType>> = sub.returnsWhatWhere()
-        for ((reg, _) in returns) {
-            // result value is in cpu or status registers, put it on the stack instead (as we're evaluating an expression tree)
-            if (reg.registerOrPair != null) {
-                when (reg.registerOrPair!!) {
-                    RegisterOrPair.A -> asmgen.out("  sta  P8ESTACK_LO,x |  dex")
-                    RegisterOrPair.Y -> asmgen.out("  tya |  sta  P8ESTACK_LO,x |  dex")
-                    RegisterOrPair.AY -> asmgen.out("  sta  P8ESTACK_LO,x |  tya |  sta  P8ESTACK_HI,x |  dex")
-                    RegisterOrPair.X -> asmgen.out("  lda  P8ZP_SCRATCH_REG |  sta  P8ESTACK_LO,x |  dex")
-                    RegisterOrPair.AX -> asmgen.out("  sta  P8ESTACK_LO,x |  lda  P8ZP_SCRATCH_REG |  sta  P8ESTACK_HI,x |  dex")
-                    RegisterOrPair.XY -> asmgen.out("  tya |  sta  P8ESTACK_HI,x |  lda  P8ZP_SCRATCH_REG |  sta  P8ESTACK_LO,x |  dex")
-                    RegisterOrPair.FAC1 -> asmgen.out("  jsr  floats.push_fac1")
-                    RegisterOrPair.FAC2 -> asmgen.out("  jsr  floats.push_fac2")
-                    RegisterOrPair.R0,
-                    RegisterOrPair.R1,
-                    RegisterOrPair.R2,
-                    RegisterOrPair.R3,
-                    RegisterOrPair.R4,
-                    RegisterOrPair.R5,
-                    RegisterOrPair.R6,
-                    RegisterOrPair.R7,
-                    RegisterOrPair.R8,
-                    RegisterOrPair.R9,
-                    RegisterOrPair.R10,
-                    RegisterOrPair.R11,
-                    RegisterOrPair.R12,
-                    RegisterOrPair.R13,
-                    RegisterOrPair.R14,
-                    RegisterOrPair.R15 -> {
-                        asmgen.out(
-                            """
-                            lda  cx16.${reg.registerOrPair.toString().lowercase()}
-                            sta  P8ESTACK_LO,x
-                            lda  cx16.${reg.registerOrPair.toString().lowercase()}+1
-                            sta  P8ESTACK_HI,x
-                            dex
-                        """)
-                    }
-                }
-            } else when(reg.statusflag) {
-                Statusflag.Pc -> {
-                    asmgen.out("""
-                        lda  #0
-                        rol  a
-                        sta  P8ESTACK_LO,x
-                        dex""")
-                }
-                Statusflag.Pz -> {
-                    asmgen.out("""
-                        beq  +
-                        lda  #0
-                        beq  ++
-+                           lda  #1
-+                           sta  P8ESTACK_LO,x
-                        dex""")
-                }
-                Statusflag.Pv -> {
-                    asmgen.out("""
-                        bvs  +
-                        lda  #0
-                        beq  ++
-+                           lda  #1
-+                           sta  P8ESTACK_LO,x
-                        dex""")
-                }
-                Statusflag.Pn -> {
-                    asmgen.out("""
-                        bmi  +
-                        lda  #0
-                        beq  ++
-+                           lda  #1
-+                           sta  P8ESTACK_LO,x
-                        dex""")
-                }
-                null -> {}
-            }
-        }
-    }
-
-    private fun translateExpression(typecast: PtTypeCast) {
-        translateExpressionInternal(typecast.value)
-        when(typecast.value.type) {
-            DataType.UBYTE, DataType.BOOL -> {
-                when(typecast.type) {
-                    DataType.UBYTE, DataType.BYTE -> {}
-                    DataType.UWORD, DataType.WORD -> {
-                        if(asmgen.isTargetCpu(CpuType.CPU65c02))
-                            asmgen.out("  stz  P8ESTACK_HI+1,x")
-                        else
-                            asmgen.out("  lda  #0  |  sta  P8ESTACK_HI+1,x")
-                    }
-                    DataType.FLOAT -> asmgen.out(" jsr  floats.stack_ub2float")
-                    in PassByReferenceDatatypes -> throw AssemblyError("cannot cast to a pass-by-reference datatype")
-                    else -> throw AssemblyError("weird type")
-                }
-            }
-            DataType.BYTE -> {
-                when(typecast.type) {
-                    DataType.UBYTE, DataType.BYTE -> {}
-                    DataType.UWORD, DataType.WORD -> asmgen.signExtendStackLsb(DataType.BYTE)
-                    DataType.FLOAT -> asmgen.out(" jsr  floats.stack_b2float")
-                    in PassByReferenceDatatypes -> throw AssemblyError("cannot cast to a pass-by-reference datatype")
-                    else -> throw AssemblyError("weird type")
-                }
-            }
-            DataType.UWORD -> {
-                when(typecast.type) {
-                    DataType.BYTE, DataType.UBYTE -> {}
-                    DataType.WORD, DataType.UWORD -> {}
-                    DataType.FLOAT -> asmgen.out(" jsr  floats.stack_uw2float")
-                    in PassByReferenceDatatypes -> throw AssemblyError("cannot cast to a pass-by-reference datatype")
-                    else -> throw AssemblyError("weird type")
-                }
-            }
-            DataType.WORD -> {
-                when(typecast.type) {
-                    DataType.BYTE, DataType.UBYTE -> {}
-                    DataType.WORD, DataType.UWORD -> {}
-                    DataType.FLOAT -> asmgen.out(" jsr  floats.stack_w2float")
-                    in PassByReferenceDatatypes -> throw AssemblyError("cannot cast to a pass-by-reference datatype")
-                    else -> throw AssemblyError("weird type")
-                }
-            }
-            DataType.FLOAT -> {
-                when(typecast.type) {
-                    DataType.UBYTE -> asmgen.out(" jsr  floats.stack_float2uw")
-                    DataType.BYTE -> asmgen.out(" jsr  floats.stack_float2w")
-                    DataType.UWORD -> asmgen.out(" jsr  floats.stack_float2uw")
-                    DataType.WORD -> asmgen.out(" jsr  floats.stack_float2w")
-                    DataType.FLOAT -> {}
-                    in PassByReferenceDatatypes -> throw AssemblyError("cannot cast to a pass-by-reference datatype")
-                    else -> throw AssemblyError("weird type")
-                }
-            }
-            DataType.STR -> {
-                if (typecast.type != DataType.UWORD && typecast.type == DataType.STR)
-                    throw AssemblyError("cannot typecast a string into another incompatitble type")
-            }
-            in PassByReferenceDatatypes -> throw AssemblyError("cannot cast pass-by-reference value into another type")
-            else -> throw AssemblyError("weird type")
-        }
-    }
-
-    private fun translateExpression(expr: PtAddressOf) {
-        val name = asmgen.asmVariableName(expr.identifier)
-        asmgen.out("  lda  #<$name |  sta  P8ESTACK_LO,x |  lda  #>$name  |  sta  P8ESTACK_HI,x  | dex")
-    }
-
-    private fun translateExpression(expr: PtNumber) {
-        when(expr.type) {
-            DataType.UBYTE, DataType.BYTE -> asmgen.out(" lda  #${expr.number.toHex()}  | sta  P8ESTACK_LO,x  | dex")
-            DataType.UWORD, DataType.WORD -> asmgen.out("""
-                lda  #<${expr.number.toHex()}
-                sta  P8ESTACK_LO,x
-                lda  #>${expr.number.toHex()}
-                sta  P8ESTACK_HI,x
-                dex
-            """)
-            DataType.FLOAT -> {
-                val floatConst = allocator.getFloatAsmConst(expr.number)
-                asmgen.out(" lda  #<$floatConst |  ldy  #>$floatConst |  jsr  floats.push_float")
-            }
-            else -> throw AssemblyError("weird type")
-        }
-    }
-
-    private fun translateExpression(expr: PtIdentifier) {
-        val varname = asmgen.asmVariableName(expr)
-        when(expr.type) {
-            DataType.UBYTE, DataType.BYTE -> {
-                asmgen.out("  lda  $varname  |  sta  P8ESTACK_LO,x  |  dex")
-            }
-            DataType.UWORD, DataType.WORD -> {
-                asmgen.out("  lda  $varname  |  sta  P8ESTACK_LO,x  |  lda  $varname+1 |  sta  P8ESTACK_HI,x |  dex")
-            }
-            DataType.FLOAT -> {
-                asmgen.out(" lda  #<$varname |  ldy  #>$varname|  jsr  floats.push_float")
-            }
-            in SplitWordArrayTypes -> {
-                throw AssemblyError("can't push address of split-word array ${expr.position}")
-            }
-            in IterableDatatypes -> {
-                asmgen.out("  lda  #<$varname  |  sta  P8ESTACK_LO,x  |  lda  #>$varname |  sta  P8ESTACK_HI,x |  dex")
-            }
-            else -> throw AssemblyError("stack push weird variable type $expr")
-        }
-    }
-
-    private fun translateExpression(expr: PtBinaryExpression) {
-        // Uses evalstack to evaluate the given expression.  THIS IS SLOW AND SHOULD BE AVOIDED!
-        if(translateSomewhatOptimized(expr.left, expr.operator, expr.right))
-            return
-
-        val leftDt = expr.left.type
-        val rightDt = expr.right.type
-
-        // compare with zero
-        if(expr.operator in ComparisonOperators) {
-            if(leftDt in NumericDatatypes && rightDt in NumericDatatypes) {
-                val rightVal = expr.right.asConstInteger()
-                if(rightVal==0)
-                    return translateComparisonWithZero(expr.left, leftDt, expr.operator)
-            }
-        }
-
-        if(leftDt==DataType.STR && rightDt==DataType.STR && expr.operator in ComparisonOperators)
-            return translateCompareStrings(expr.left, expr.operator, expr.right)
-
-        if((leftDt in ByteDatatypes && rightDt !in ByteDatatypes)
-                || (leftDt in WordDatatypes && rightDt !in WordDatatypes))
-            throw AssemblyError("binary operator ${expr.operator} left/right dt not identical")
-
-        // the general, non-optimized cases
-        // TODO optimize more cases.... (or one day just don't use the evalstack at all anymore)
-        translateExpressionInternal(expr.left)
-        translateExpressionInternal(expr.right)
-        when (leftDt) {
-            in ByteDatatypes -> translateBinaryOperatorBytes(expr.operator, leftDt)
-            in WordDatatypes -> translateBinaryOperatorWords(expr.operator, leftDt)
-            DataType.FLOAT -> translateBinaryOperatorFloats(expr.operator)
-            else -> throw AssemblyError("non-numerical datatype")
-        }
-    }
-
-    private fun translateSomewhatOptimized(left: PtExpression, operator: String, right: PtExpression): Boolean {
-        val leftDt = left.type
-        val rightDt = right.type
-        when(operator) {
-            "+" -> {
-                if(leftDt in IntegerDatatypes && rightDt in IntegerDatatypes) {
-                    val leftVal = left.asConstInteger()
-                    val rightVal = right.asConstInteger()
-                    if (leftVal!=null && leftVal in -4..4) {
-                        translateExpressionInternal(right)
-                        if(rightDt in ByteDatatypes) {
-                            val incdec = if(leftVal<0) "dec" else "inc"
-                            repeat(leftVal.absoluteValue) {
-                                asmgen.out("  $incdec  P8ESTACK_LO+1,x")
-                            }
-                        } else {
-                            // word
-                            if(leftVal<0) {
-                                repeat(leftVal.absoluteValue) {
-                                    asmgen.out("""
-                                        lda  P8ESTACK_LO+1,x
-                                        bne  +
-                                        dec  P8ESTACK_HI+1,x
-+                                       dec  P8ESTACK_LO+1,x""")
-                                }
-                            } else {
-                                repeat(leftVal) {
-                                    asmgen.out("""
-                                        inc  P8ESTACK_LO+1,x
-                                        bne  +
-                                        inc  P8ESTACK_HI+1,x
-+""")
-                                }
-                            }
-                        }
-                        return true
-                    }
-                    else if (rightVal!=null && rightVal in -4..4)
-                    {
-                        translateExpressionInternal(left)
-                        if(leftDt in ByteDatatypes) {
-                            val incdec = if(rightVal<0) "dec" else "inc"
-                            repeat(rightVal.absoluteValue) {
-                                asmgen.out("  $incdec  P8ESTACK_LO+1,x")
-                            }
-                        } else {
-                            // word
-                            if(rightVal<0) {
-                                repeat(rightVal.absoluteValue) {
-                                    asmgen.out("""
-                                        lda  P8ESTACK_LO+1,x
-                                        bne  +
-                                        dec  P8ESTACK_HI+1,x
-+                                       dec  P8ESTACK_LO+1,x""")
-                                }
-                            } else {
-                                repeat(rightVal) {
-                                    asmgen.out("""
-                                        inc  P8ESTACK_LO+1,x
-                                        bne  +
-                                        inc  P8ESTACK_HI+1,x
-+""")
-                                }
-                            }
-                        }
-                        return true
-                    }
-                }
-            }
-            "-" -> {
-                if(leftDt in IntegerDatatypes && rightDt in IntegerDatatypes) {
-                    val rightVal = right.asConstInteger()
-                    if (rightVal!=null && rightVal in -4..4)
-                    {
-                        translateExpressionInternal(left)
-                        if(leftDt in ByteDatatypes) {
-                            val incdec = if(rightVal<0) "inc" else "dec"
-                            repeat(rightVal.absoluteValue) {
-                                asmgen.out("  $incdec  P8ESTACK_LO+1,x")
-                            }
-                        } else {
-                            // word
-                            if(rightVal>0) {
-                                repeat(rightVal.absoluteValue) {
-                                    asmgen.out("""
-                                        lda  P8ESTACK_LO+1,x
-                                        bne  +
-                                        dec  P8ESTACK_HI+1,x
-+                                       dec  P8ESTACK_LO+1,x""")
-                                }
-                            } else {
-                                repeat(rightVal) {
-                                    asmgen.out("""
-                                        inc  P8ESTACK_LO+1,x
-                                        bne  +
-                                        inc  P8ESTACK_HI+1,x
-+""")
-                                }
-                            }
-                        }
-                        return true
-                    }
-                }
-            }
-            ">>" -> {
-                val amount = right.asConstInteger()
-                if(amount!=null) {
-                    translateExpressionInternal(left)
-                    when (leftDt) {
-                        DataType.UBYTE -> {
-                            if (amount <= 2)
-                                repeat(amount) { asmgen.out(" lsr  P8ESTACK_LO+1,x") }
-                            else {
-                                asmgen.out(" lda  P8ESTACK_LO+1,x")
-                                repeat(amount) { asmgen.out(" lsr  a") }
-                                asmgen.out(" sta  P8ESTACK_LO+1,x")
-                            }
-                        }
-                        DataType.BYTE -> {
-                            if (amount <= 2)
-                                repeat(amount) { asmgen.out(" lda  P8ESTACK_LO+1,x |  asl  a |  ror  P8ESTACK_LO+1,x") }
-                            else {
-                                asmgen.out(" lda  P8ESTACK_LO+1,x |  sta  P8ZP_SCRATCH_B1")
-                                repeat(amount) { asmgen.out(" asl  a |  ror  P8ZP_SCRATCH_B1 |  lda  P8ZP_SCRATCH_B1") }
-                                asmgen.out(" sta  P8ESTACK_LO+1,x")
-                            }
-                        }
-                        DataType.UWORD -> {
-                            if(amount>=16) {
-                                if(asmgen.isTargetCpu(CpuType.CPU65c02))
-                                    asmgen.out("  stz  P8ESTACK_LO+1,x |  stz  P8ESTACK_HI+1,x")
-                                else
-                                    asmgen.out("  lda  #0 |  sta  P8ESTACK_LO+1,x |  sta  P8ESTACK_HI+1,x")
-                                return true
-                            }
-                            var amountLeft = amount
-                            while (amountLeft >= 7) {
-                                asmgen.out(" jsr  math.shift_right_uw_7")
-                                amountLeft -= 7
-                            }
-                            if (amountLeft in 0..2)
-                                repeat(amountLeft) { asmgen.out(" lsr  P8ESTACK_HI+1,x |  ror  P8ESTACK_LO+1,x") }
-                            else
-                                asmgen.out(" jsr  math.shift_right_uw_$amountLeft")
-                        }
-                        DataType.WORD -> {
-                            if(amount>=16) {
-                                asmgen.out("""
-                                    lda  P8ESTACK_HI+1,x
-                                    bmi  +
-                                    lda  #0
-                                    sta  P8ESTACK_LO+1,x
-                                    sta  P8ESTACK_HI+1,x
-                                    beq  ++
-+                                   lda  #255
-                                    sta  P8ESTACK_LO+1,x
-                                    sta  P8ESTACK_HI+1,x
-+""")
-                                return true
-                            }
-                            var amountLeft = amount
-                            while (amountLeft >= 7) {
-                                asmgen.out(" jsr  math.shift_right_w_7")
-                                amountLeft -= 7
-                            }
-                            if (amountLeft in 0..2)
-                                repeat(amountLeft) { asmgen.out(" lda  P8ESTACK_HI+1,x |  asl  a  |  ror  P8ESTACK_HI+1,x |  ror  P8ESTACK_LO+1,x") }
-                            else
-                                asmgen.out(" jsr  math.shift_right_w_$amountLeft")
-                        }
-                        else -> throw AssemblyError("weird type")
-                    }
-                    return true
-                }
-            }
-            "<<" -> {
-                val amount = right.asConstInteger()
-                if(amount!=null) {
-                    translateExpressionInternal(left)
-                    if (leftDt in ByteDatatypes) {
-                        if (amount <= 2)
-                            repeat(amount) { asmgen.out("  asl  P8ESTACK_LO+1,x") }
-                        else {
-                            asmgen.out("  lda  P8ESTACK_LO+1,x")
-                            repeat(amount) { asmgen.out("  asl  a") }
-                            asmgen.out("  sta  P8ESTACK_LO+1,x")
-                        }
-                    } else {
-                        var amountLeft = amount
-                        while (amountLeft >= 7) {
-                            asmgen.out(" jsr  math.shift_left_w_7")
-                            amountLeft -= 7
-                        }
-                        if (amountLeft in 0..2)
-                            repeat(amountLeft) { asmgen.out("  asl  P8ESTACK_LO+1,x |  rol  P8ESTACK_HI+1,x") }
-                        else
-                            asmgen.out(" jsr  math.shift_left_w_$amountLeft")
-                    }
-                    return true
-                }
-            }
-            "*" -> {
-                if(leftDt in IntegerDatatypes && rightDt in IntegerDatatypes) {
-                    val leftVar = left as? PtIdentifier
-                    val rightVar = right as? PtIdentifier
-                    if(leftVar!=null && rightVar!=null && leftVar==rightVar) {
-                        translateSquared(leftVar, leftDt)
-                        return true
-                    }
-                }
-
-                val value = right as? PtNumber
-                if(value!=null) {
-                    if(rightDt in IntegerDatatypes) {
-                        val amount = value.number.toInt()
-                        if(amount==2) {
-                            // optimize x*2 common case
-                            translateExpressionInternal(left)
-                            if(leftDt in ByteDatatypes) {
-                                asmgen.out("  asl  P8ESTACK_LO+1,x")
-                            } else {
-                                asmgen.out("  asl  P8ESTACK_LO+1,x |  rol  P8ESTACK_HI+1,x")
-                            }
-                            return true
-                        }
-                        when(rightDt) {
-                            DataType.UBYTE -> {
-                                if(amount in asmgen.optimizedByteMultiplications) {
-                                    translateExpressionInternal(left)
-                                    asmgen.out(" jsr  math.stack_mul_byte_$amount")
-                                    return true
-                                }
-                            }
-                            DataType.BYTE -> {
-                                if(amount in asmgen.optimizedByteMultiplications) {
-                                    translateExpressionInternal(left)
-                                    asmgen.out(" jsr  math.stack_mul_byte_$amount")
-                                    return true
-                                }
-                                if(amount.absoluteValue in asmgen.optimizedByteMultiplications) {
-                                    translateExpressionInternal(left)
-                                    asmgen.out(" jsr  prog8_lib.neg_b |  jsr  math.stack_mul_byte_${amount.absoluteValue}")
-                                    return true
-                                }
-                            }
-                            DataType.UWORD -> {
-                                if(amount in asmgen.optimizedWordMultiplications) {
-                                    translateExpressionInternal(left)
-                                    asmgen.out(" jsr  math.stack_mul_word_$amount")
-                                    return true
-                                }
-                            }
-                            DataType.WORD -> {
-                                if(amount in asmgen.optimizedWordMultiplications) {
-                                    translateExpressionInternal(left)
-                                    asmgen.out(" jsr  math.stack_mul_word_$amount")
-                                    return true
-                                }
-                                if(amount.absoluteValue in asmgen.optimizedWordMultiplications) {
-                                    translateExpressionInternal(left)
-                                    asmgen.out(" jsr  prog8_lib.neg_w |  jsr  math.stack_mul_word_${amount.absoluteValue}")
-                                    return true
-                                }
-                            }
-                            else -> {}
-                        }
-                    }
-                }
-            }
-            "/" -> {
-                if(leftDt in IntegerDatatypes && rightDt in IntegerDatatypes) {
-                    val rightVal = right.asConstInteger()
-                    if(rightVal!=null && rightVal==2) {
-                        translateExpressionInternal(left)
-                        when (leftDt) {
-                            DataType.UBYTE -> {
-                                asmgen.out("  lsr  P8ESTACK_LO+1,x")
-                            }
-                            DataType.UWORD -> {
-                                asmgen.out("  lsr  P8ESTACK_HI+1,x |  ror  P8ESTACK_LO+1,x")
-                            }
-                            DataType.BYTE -> {
-                                // signed divide using shift needs adjusting of negative value to get correct rounding towards zero
-                                asmgen.out("""
-                                    lda  P8ESTACK_LO+1,x
-                                    bpl  +
-                                    inc  P8ESTACK_LO+1,x
-                                    lda  P8ESTACK_LO+1,x
-+                                   asl  a
-                                    ror  P8ESTACK_LO+1,x""")
-                            }
-                            DataType.WORD -> {
-                                // signed divide using shift needs adjusting of negative value to get correct rounding towards zero
-                                asmgen.out("""
-                                    lda  P8ESTACK_HI+1,x
-                                    bpl  ++
-                                    inc  P8ESTACK_LO+1,x
-                                    bne  +
-                                    inc  P8ESTACK_HI+1,x
-+                                   lda  P8ESTACK_HI+1,x
-+                                   asl  a
-                                    ror  P8ESTACK_HI+1,x
-                                    ror  P8ESTACK_LO+1,x""")
-                            }
-                            else -> throw AssemblyError("weird dt")
-                        }
-                        return true
-                    }
-                }
-            }
-        }
-
-        return false
-    }
-
-    private fun translateComparisonWithZero(expr: PtExpression, dt: DataType, operator: String) {
-        if(expr.isSimple()) {
-            if(operator=="!=") {
-                when (dt) {
-                    in ByteDatatypes -> {
-                        asmgen.assignExpressionToRegister(expr, RegisterOrPair.A, dt == DataType.BYTE)
-                        asmgen.out("""
-                            beq  +
-                            lda  #1
-+                           sta  P8ESTACK_LO,x
-                            dex""")
-                        return
-                    }
-                    in WordDatatypes -> {
-                        asmgen.assignExpressionToRegister(expr, RegisterOrPair.AY, dt == DataType.WORD)
-                        asmgen.out("""
-                            sty  P8ZP_SCRATCH_B1 
-                            ora  P8ZP_SCRATCH_B1
-                            beq  +
-                            lda  #1
-+                           sta  P8ESTACK_LO,x
-                            dex""")
-                        return
-                    }
-                    DataType.FLOAT -> {
-                        asmgen.assignExpressionToRegister(expr, RegisterOrPair.FAC1, true)
-                        asmgen.out("""
-                            jsr  floats.SIGN
-                            sta  P8ESTACK_LO,x
-                            dex""")
-                        return
-                    }
-                    else -> {}
-                }
-            }
-            /* operator == is not worth it to special case, the code is mostly larger */
-        }
-        translateExpressionInternal(expr)
-        when(operator) {
-            "==" -> {
-                when(dt) {
-                    DataType.UBYTE, DataType.BYTE -> asmgen.out("  jsr  prog8_lib.equalzero_b")
-                    DataType.UWORD, DataType.WORD -> asmgen.out("  jsr  prog8_lib.equalzero_w")
-                    DataType.FLOAT -> asmgen.out("  jsr  floats.equal_zero")
-                    else -> throw AssemblyError("wrong dt")
-                }
-            }
-            "!=" -> {
-                when(dt) {
-                    DataType.UBYTE, DataType.BYTE -> asmgen.out("  jsr  prog8_lib.notequalzero_b")
-                    DataType.UWORD, DataType.WORD -> asmgen.out("  jsr  prog8_lib.notequalzero_w")
-                    DataType.FLOAT -> asmgen.out("  jsr  floats.notequal_zero")
-                    else -> throw AssemblyError("wrong dt")
-                }
-            }
-            "<" -> {
-                if(dt==DataType.UBYTE || dt==DataType.UWORD)
-                    return translateExpressionInternal(PtNumber.fromBoolean(false, expr.position))
-                when(dt) {
-                    DataType.BYTE -> asmgen.out("  jsr  prog8_lib.lesszero_b")
-                    DataType.WORD -> asmgen.out("  jsr  prog8_lib.lesszero_w")
-                    DataType.FLOAT -> asmgen.out("  jsr  floats.less_zero")
-                    else -> throw AssemblyError("wrong dt")
-                }
-            }
-            ">" -> {
-                when(dt) {
-                    DataType.UBYTE -> asmgen.out("  jsr  prog8_lib.greaterzero_ub")
-                    DataType.BYTE -> asmgen.out("  jsr  prog8_lib.greaterzero_sb")
-                    DataType.UWORD -> asmgen.out("  jsr  prog8_lib.greaterzero_uw")
-                    DataType.WORD -> asmgen.out("  jsr  prog8_lib.greaterzero_sw")
-                    DataType.FLOAT -> asmgen.out("  jsr  floats.greater_zero")
-                    else -> throw AssemblyError("wrong dt")
-                }
-            }
-            "<=" -> {
-                when(dt) {
-                    DataType.UBYTE -> asmgen.out("  jsr  prog8_lib.equalzero_b")
-                    DataType.BYTE -> asmgen.out("  jsr  prog8_lib.lessequalzero_sb")
-                    DataType.UWORD -> asmgen.out("  jsr  prog8_lib.equalzero_w")
-                    DataType.WORD -> asmgen.out("  jsr  prog8_lib.lessequalzero_sw")
-                    DataType.FLOAT -> asmgen.out("  jsr  floats.lessequal_zero")
-                    else -> throw AssemblyError("wrong dt")
-                }
-            }
-            ">=" -> {
-                if(dt==DataType.UBYTE || dt==DataType.UWORD)
-                    return translateExpressionInternal(PtNumber.fromBoolean(true, expr.position))
-                when(dt) {
-                    DataType.BYTE -> asmgen.out("  jsr  prog8_lib.greaterequalzero_sb")
-                    DataType.WORD -> asmgen.out("  jsr  prog8_lib.greaterequalzero_sw")
-                    DataType.FLOAT -> asmgen.out("  jsr  floats.greaterequal_zero")
-                    else -> throw AssemblyError("wrong dt")
-                }
-            }
-            else -> throw AssemblyError("invalid comparison operator")
-        }
-    }
-
-    private fun translateSquared(variable: PtIdentifier, dt: DataType) {
-        val asmVar = asmgen.asmVariableName(variable)
-        when(dt) {
-            DataType.BYTE, DataType.UBYTE -> {
-                asmgen.out("  lda  $asmVar")
-                asmgen.signExtendAYlsb(dt)
-                asmgen.out("  jsr  math.square")
-            }
-            DataType.UWORD, DataType.WORD -> {
-                asmgen.out("  lda  $asmVar |  ldy  $asmVar+1 |  jsr  math.square")
-            }
-            else -> throw AssemblyError("require integer dt for square")
-        }
-        asmgen.out("  sta  P8ESTACK_LO,x |  tya |  sta  P8ESTACK_HI,x |  dex")
-    }
-
-    private fun translateExpression(expr: PtPrefix) {
-        translateExpressionInternal(expr.value)
-        when(expr.operator) {
-            "+" -> {}
-            "-" -> {
-                when(expr.type) {
-                    in ByteDatatypes -> asmgen.out("  jsr  prog8_lib.neg_b")
-                    in WordDatatypes -> asmgen.out("  jsr  prog8_lib.neg_w")
-                    DataType.FLOAT -> asmgen.out("  jsr  floats.neg_f")
-                    else -> throw AssemblyError("weird type")
-                }
-            }
-            "~" -> {
-                when(expr.type) {
-                    in ByteDatatypes ->
-                        asmgen.out("""
-                            lda  P8ESTACK_LO+1,x
-                            eor  #255
-                            sta  P8ESTACK_LO+1,x
-                            """)
-                    in WordDatatypes -> asmgen.out("  jsr  prog8_lib.inv_word")
-                    else -> throw AssemblyError("weird type")
-                }
-            }
-            else -> throw AssemblyError("invalid prefix operator ${expr.operator}")
-        }
-    }
-
-    private fun translateExpression(arrayExpr: PtArrayIndexer) {
-        val elementDt = arrayExpr.type
-        val arrayVarName = asmgen.asmVariableName(arrayExpr.variable)
-
-        if(arrayExpr.variable.type==DataType.UWORD) {
-            // indexing a pointer var instead of a real array or string
-            if(elementDt !in ByteDatatypes)
-                throw AssemblyError("non-array var indexing requires bytes dt")
-            if(arrayExpr.index.type != DataType.UBYTE)
-                throw AssemblyError("non-array var indexing requires bytes index")
-            asmgen.loadScaledArrayIndexIntoRegister(arrayExpr, elementDt, CpuRegister.Y)
-            if(asmgen.isZpVar(arrayExpr.variable)) {
-                asmgen.out("  lda  ($arrayVarName),y")
-            } else {
-                asmgen.out("  lda  $arrayVarName |  sta  P8ZP_SCRATCH_W1 |  lda  $arrayVarName+1 |  sta  P8ZP_SCRATCH_W1+1")
-                asmgen.out("  lda  (P8ZP_SCRATCH_W1),y")
-            }
-            asmgen.out("  sta  P8ESTACK_LO,x |  dex")
-            return
-        }
-
-        if(arrayExpr.splitWords)
-            TODO("split words expression ${arrayExpr.position}")
-
-        val constIndexNum = arrayExpr.index.asConstInteger()
-        if(constIndexNum!=null) {
-            val indexValue = constIndexNum * program.memsizer.memorySize(elementDt)
-            when(elementDt) {
-                in ByteDatatypes -> {
-                    asmgen.out("  lda  $arrayVarName+$indexValue |  sta  P8ESTACK_LO,x |  dex")
-                }
-                in WordDatatypes -> {
-                    asmgen.out("  lda  $arrayVarName+$indexValue |  sta  P8ESTACK_LO,x |  lda  $arrayVarName+$indexValue+1 |  sta  P8ESTACK_HI,x |  dex")
-                }
-                DataType.FLOAT -> {
-                    asmgen.out("  lda  #<($arrayVarName+$indexValue) |  ldy  #>($arrayVarName+$indexValue) |  jsr  floats.push_float")
-                }
-                else -> throw AssemblyError("weird element type")
-            }
-        } else {
-            when(elementDt) {
-                in ByteDatatypes -> {
-                    asmgen.loadScaledArrayIndexIntoRegister(arrayExpr, elementDt, CpuRegister.Y)
-                    asmgen.out(" lda  $arrayVarName,y |  sta  P8ESTACK_LO,x |  dex")
-                }
-                in WordDatatypes -> {
-                    asmgen.loadScaledArrayIndexIntoRegister(arrayExpr, elementDt, CpuRegister.Y)
-                    asmgen.out(" lda  $arrayVarName,y |  sta  P8ESTACK_LO,x |  lda  $arrayVarName+1,y |  sta  P8ESTACK_HI,x |  dex")
-                }
-                DataType.FLOAT -> {
-                    asmgen.loadScaledArrayIndexIntoRegister(arrayExpr, elementDt, CpuRegister.A)
-                    asmgen.out("""
-                        ldy  #>$arrayVarName
-                        clc
-                        adc  #<$arrayVarName
-                        bcc  +
-                        iny
-+                       jsr  floats.push_float""")
-                }
-                else -> throw AssemblyError("weird dt")
-            }
-
-        }
-    }
-
-    private fun translateBinaryOperatorBytes(operator: String, types: DataType) {
-        when(operator) {
-            "*" -> asmgen.out("  jsr  prog8_lib.mul_byte")  //  the optimized routines should have been checked earlier
-            "/" -> asmgen.out(if(types==DataType.UBYTE) "  jsr  prog8_lib.idiv_ub" else "  jsr  prog8_lib.idiv_b")
-            "%" -> {
-                if(types==DataType.BYTE)
-                    throw AssemblyError("remainder of signed integers is not properly defined/implemented, use unsigned instead")
-                asmgen.out("  jsr prog8_lib.remainder_ub")
-            }
-            "+" -> asmgen.out("""
-                lda  P8ESTACK_LO+2,x
-                clc
-                adc  P8ESTACK_LO+1,x
-                inx
-                sta  P8ESTACK_LO+1,x
-                """)
-            "-" -> asmgen.out("""
-                lda  P8ESTACK_LO+2,x
-                sec
-                sbc  P8ESTACK_LO+1,x
-                inx
-                sta  P8ESTACK_LO+1,x
-                """)
-            "<<" -> asmgen.out("  jsr  prog8_lib.shiftleft_b")
-            ">>" -> asmgen.out("  jsr  prog8_lib.shiftright_b")
-            "<" -> asmgen.out(if(types==DataType.UBYTE) "  jsr  prog8_lib.less_ub" else "  jsr  prog8_lib.less_b")
-            ">" -> asmgen.out(if(types==DataType.UBYTE) "  jsr  prog8_lib.greater_ub" else "  jsr  prog8_lib.greater_b")
-            "<=" -> asmgen.out(if(types==DataType.UBYTE) "  jsr  prog8_lib.lesseq_ub" else "  jsr  prog8_lib.lesseq_b")
-            ">=" -> asmgen.out(if(types==DataType.UBYTE) "  jsr  prog8_lib.greatereq_ub" else "  jsr  prog8_lib.greatereq_b")
-            "==" -> asmgen.out("  jsr  prog8_lib.equal_b")
-            "!=" -> asmgen.out("  jsr  prog8_lib.notequal_b")
-            "&" -> asmgen.out("  jsr  prog8_lib.bitand_b")
-            "^" -> asmgen.out("  jsr  prog8_lib.bitxor_b")
-            "|" -> asmgen.out("  jsr  prog8_lib.bitor_b")
-            else -> throw AssemblyError("invalid operator $operator")
-        }
-    }
-
-    private fun translateBinaryOperatorWords(operator: String, dt: DataType) {
-        when(operator) {
-            "*" -> asmgen.out("  jsr  prog8_lib.mul_word")
-            "/" -> asmgen.out(if(dt==DataType.UWORD) "  jsr  prog8_lib.idiv_uw" else "  jsr  prog8_lib.idiv_w")
-            "%" -> {
-                if(dt==DataType.WORD)
-                    throw AssemblyError("remainder of signed integers is not properly defined/implemented, use unsigned instead")
-                asmgen.out("  jsr prog8_lib.remainder_uw")
-            }
-            "+" -> asmgen.out("  jsr  prog8_lib.add_w")
-            "-" -> asmgen.out("  jsr  prog8_lib.sub_w")
-            "<<" -> asmgen.out("  jsr  math.shift_left_w")
-            ">>" -> {
-                if(dt==DataType.UWORD)
-                    asmgen.out("  jsr  math.shift_right_uw")
-                else
-                    asmgen.out("  jsr  math.shift_right_w")
-            }
-            "<" -> asmgen.out(if(dt==DataType.UWORD) "  jsr  prog8_lib.less_uw" else "  jsr  prog8_lib.less_w")
-            ">" -> asmgen.out(if(dt==DataType.UWORD) "  jsr  prog8_lib.greater_uw" else "  jsr  prog8_lib.greater_w")
-            "<=" -> asmgen.out(if(dt==DataType.UWORD) "  jsr  prog8_lib.lesseq_uw" else "  jsr  prog8_lib.lesseq_w")
-            ">=" -> asmgen.out(if(dt==DataType.UWORD) "  jsr  prog8_lib.greatereq_uw" else "  jsr  prog8_lib.greatereq_w")
-            "==" -> asmgen.out("  jsr  prog8_lib.equal_w")
-            "!=" -> asmgen.out("  jsr  prog8_lib.notequal_w")
-            "&" -> asmgen.out("  jsr  prog8_lib.bitand_w")
-            "^" -> asmgen.out("  jsr  prog8_lib.bitxor_w")
-            "|" -> asmgen.out("  jsr  prog8_lib.bitor_w")
-            else -> throw AssemblyError("invalid operator $operator")
-        }
-    }
-
-    private fun translateBinaryOperatorFloats(operator: String) {
-        when(operator) {
-            "*" -> asmgen.out("  jsr  floats.mul_f")
-            "/" -> asmgen.out("  jsr  floats.div_f")
-            "+" -> asmgen.out("  jsr  floats.add_f")
-            "-" -> asmgen.out("  jsr  floats.sub_f")
-            "<" -> asmgen.out("  jsr  floats.less_f")
-            ">" -> asmgen.out("  jsr  floats.greater_f")
-            "<=" -> asmgen.out("  jsr  floats.lesseq_f")
-            ">=" -> asmgen.out("  jsr  floats.greatereq_f")
-            "==" -> asmgen.out("  jsr  floats.equal_f")
-            "!=" -> asmgen.out("  jsr  floats.notequal_f")
-            "%", "<<", ">>", "&", "^", "|" -> throw AssemblyError("requires integer datatype")
-            else -> throw AssemblyError("invalid operator $operator")
-        }
-    }
-
-    private fun translateCompareStrings(s1: PtExpression, operator: String, s2: PtExpression) {
-        asmgen.assignExpressionToVariable(s1, "prog8_lib.strcmp_expression._arg_s1", DataType.UWORD)
-        asmgen.assignExpressionToVariable(s2, "prog8_lib.strcmp_expression._arg_s2", DataType.UWORD)
-        asmgen.out(" jsr  prog8_lib.strcmp_expression")    // result  of compare is in A
-        compareStringsProcessResultInA(operator)
-    }
-
-    private fun compareStringsProcessResultInA(operator: String) {
-        when(operator) {
-            "==" -> asmgen.out(" and  #1 |  eor  #1 |  sta  P8ESTACK_LO,x")
-            "!=" -> asmgen.out(" and  #1 |  sta  P8ESTACK_LO,x")
-            "<=" -> asmgen.out("""
-                bpl  +
-                lda  #1
-                bne  ++
-+               lda  #0
-+               sta  P8ESTACK_LO,x""")
-            ">=" -> asmgen.out("""
-                bmi  +
-                lda  #1
-                bne  ++
-+               lda  #0
-+               sta  P8ESTACK_LO,x""")
-            "<" -> asmgen.out("""
-                bmi  +
-                lda  #0
-                beq  ++
-+               lda  #1
-+               sta  P8ESTACK_LO,x""")
-            ">" -> asmgen.out("""
-                bpl  +
-                lda  #0
-                beq  ++
-+               lda  #1
-+               sta  P8ESTACK_LO,x""")
-        }
-        asmgen.out("  dex")
-    }
-}

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

@@ -6,26 +6,6 @@ import prog8.code.ast.PtSub
 import prog8.code.core.*
 
 
-internal fun IPtSubroutine.regXasResult(): Boolean =
-    (this is PtAsmSub) && this.returns.any { it.first.registerOrPair in arrayOf(RegisterOrPair.X, RegisterOrPair.AX, RegisterOrPair.XY) }
-
-internal fun IPtSubroutine.shouldSaveX(): Boolean =
-    this.regXasResult() || (this is PtAsmSub && (CpuRegister.X in this.clobbers || regXasParam()))
-
-internal fun PtAsmSub.regXasParam(): Boolean =
-    parameters.any { it.first.registerOrPair in arrayOf(RegisterOrPair.X, RegisterOrPair.AX, RegisterOrPair.XY) }
-
-internal class KeepAresult(val saveOnEntry: Boolean, val saveOnReturn: Boolean)
-
-internal fun PtAsmSub.shouldKeepA(): KeepAresult {
-    // determine if A's value should be kept when preparing for calling the subroutine, and when returning from it
-
-    // it seems that we never have to save A when calling? will be loaded correctly after setup.
-    // but on return it depends on wether the routine returns something in A.
-    val saveAonReturn = returns.any { it.first.registerOrPair==RegisterOrPair.A || it.first.registerOrPair==RegisterOrPair.AY || it.first.registerOrPair==RegisterOrPair.AX }
-    return KeepAresult(false, saveAonReturn)
-}
-
 internal fun IPtSubroutine.returnsWhatWhere(): List<Pair<RegisterOrStatusflag, DataType>> {
     when(this) {
         is PtAsmSub -> {

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

@@ -1,13 +1,18 @@
 package prog8.codegen.cpu6502
 
 import com.github.michaelbull.result.fold
-import prog8.code.ast.*
+import prog8.code.StMemVar
+import prog8.code.StStaticVariable
+import prog8.code.ast.PtForLoop
+import prog8.code.ast.PtIdentifier
+import prog8.code.ast.PtRange
 import prog8.code.core.*
 import kotlin.math.absoluteValue
 
-internal class ForLoopsAsmGen(private val program: PtProgram,
-                              private val asmgen: AsmGen6502Internal,
-                              private val zeropage: Zeropage) {
+internal class ForLoopsAsmGen(
+    private val asmgen: AsmGen6502Internal,
+    private val zeropage: Zeropage
+) {
 
     internal fun translate(stmt: PtForLoop) {
         val iterableDt = stmt.iterable.type
@@ -254,11 +259,11 @@ $loopLabel""")
                 sec
                 sbc  #<${stepsize.absoluteValue}
                 sta  $varname
-                pha
+                tax
                 lda  $varname+1
                 sbc  #>${stepsize.absoluteValue}
                 sta  $varname+1
-                pla
+                txa
 $modifiedLabel2 cmp  #0    ; modified 
                 lda  $varname+1
 $modifiedLabel  sbc  #0    ; modified
@@ -331,11 +336,10 @@ $endLabel""")
         asmgen.loopEndLabels.push(endLabel)
         val iterableName = asmgen.asmVariableName(ident)
         val symbol = asmgen.symbolTable.lookup(ident.name)
-        val decl = symbol!!.astNode as IPtVariable
-        val numElements = when(decl) {
-            is PtConstant -> throw AssemblyError("length of non-array requested")
-            is PtMemMapped -> decl.arraySize
-            is PtVariable -> decl.arraySize
+        val numElements = when(symbol) {
+            is StStaticVariable -> symbol.length!!
+            is StMemVar -> symbol.length!!
+            else -> 0
         }
         when(iterableDt) {
             DataType.STR -> {
@@ -363,7 +367,7 @@ $loopLabel          sty  $indexVar
                     lda  $iterableName,y
                     sta  ${asmgen.asmVariableName(stmt.variable)}""")
                 asmgen.translate(stmt.statements)
-                if(numElements!!<=255u) {
+                if(numElements<=255) {
                     asmgen.out("""
                         ldy  $indexVar
                         iny
@@ -378,11 +382,11 @@ $loopLabel          sty  $indexVar
                         bne  $loopLabel
                         beq  $endLabel""")
                 }
-                if(numElements>=16u) {
+                if(numElements>=16) {
                     // allocate index var on ZP if possible
                     val result = zeropage.allocate(indexVar, DataType.UBYTE, null, stmt.position, asmgen.errors)
                     result.fold(
-                        success = { (address,_)-> asmgen.out("""$indexVar = $address  ; auto zp UBYTE""") },
+                        success = { (address, _, _)-> asmgen.out("""$indexVar = $address  ; auto zp UBYTE""") },
                         failure = { asmgen.out("$indexVar    .byte  0") }
                     )
                 } else {
@@ -391,7 +395,7 @@ $loopLabel          sty  $indexVar
                 asmgen.out(endLabel)
             }
             DataType.ARRAY_W, DataType.ARRAY_UW -> {
-                val length = numElements!! * 2u
+                val length = numElements * 2
                 val indexVar = asmgen.makeLabel("for_index")
                 val loopvarName = asmgen.asmVariableName(stmt.variable)
                 asmgen.out("""
@@ -402,7 +406,7 @@ $loopLabel          sty  $indexVar
                     lda  $iterableName+1,y
                     sta  $loopvarName+1""")
                 asmgen.translate(stmt.statements)
-                if(length<=127u) {
+                if(length<=127) {
                     asmgen.out("""
                         ldy  $indexVar
                         iny
@@ -419,7 +423,7 @@ $loopLabel          sty  $indexVar
                         bne  $loopLabel
                         beq  $endLabel""")
                 }
-                if(length>=16u) {
+                if(length>=16) {
                     // allocate index var on ZP if possible
                     val result = zeropage.allocate(indexVar, DataType.UBYTE, null, stmt.position, asmgen.errors)
                     result.fold(
@@ -432,7 +436,6 @@ $loopLabel          sty  $indexVar
                 asmgen.out(endLabel)
             }
             DataType.ARRAY_UW_SPLIT, DataType.ARRAY_W_SPLIT -> {
-                numElements!!
                 val indexVar = asmgen.makeLabel("for_index")
                 val loopvarName = asmgen.asmVariableName(stmt.variable)
                 asmgen.out("""
@@ -443,7 +446,7 @@ $loopLabel          sty  $indexVar
                     lda  ${iterableName}_msb,y
                     sta  $loopvarName+1""")
                 asmgen.translate(stmt.statements)
-                if(numElements<=255u) {
+                if(numElements<=255) {
                     asmgen.out("""
                         ldy  $indexVar
                         iny
@@ -458,7 +461,7 @@ $loopLabel          sty  $indexVar
                         bne  $loopLabel
                         beq  $endLabel""")
                 }
-                if(numElements>=16u) {
+                if(numElements>=16) {
                     // allocate index var on ZP if possible
                     val result = zeropage.allocate(indexVar, DataType.UBYTE, null, stmt.position, asmgen.errors)
                     result.fold(

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

@@ -11,42 +11,10 @@ import prog8.codegen.cpu6502.assignment.TargetStorageKind
 internal class FunctionCallAsmGen(private val program: PtProgram, private val asmgen: AsmGen6502Internal) {
 
     internal fun translateFunctionCallStatement(stmt: PtFunctionCall) {
-        saveXbeforeCall(stmt)
         translateFunctionCall(stmt)
-        restoreXafterCall(stmt)
         // just ignore any result values from the function call.
     }
 
-    internal fun saveXbeforeCall(stmt: PtFunctionCall) {
-        val symbol = asmgen.symbolTable.lookup(stmt.name)
-        val sub = symbol!!.astNode as IPtSubroutine
-        if(sub.shouldSaveX()) {
-            if(sub is PtAsmSub) {
-                val regSaveOnStack = sub.address == null       // rom-routines don't require registers to be saved on stack, normal subroutines do because they can contain nested calls
-                if (regSaveOnStack)
-                    asmgen.saveRegisterStack(CpuRegister.X, sub.shouldKeepA().saveOnEntry)
-                else
-                    asmgen.saveRegisterLocal(CpuRegister.X, stmt.definingISub()!!)
-            } else
-                asmgen.saveRegisterLocal(CpuRegister.X, stmt.definingISub()!!)
-        }
-    }
-
-    internal fun restoreXafterCall(stmt: PtFunctionCall) {
-        val symbol = asmgen.symbolTable.lookup(stmt.name)
-        val sub = symbol!!.astNode as IPtSubroutine
-        if(sub.shouldSaveX()) {
-            if(sub is PtAsmSub) {
-                val regSaveOnStack = sub.address == null       // rom-routines don't require registers to be saved on stack, normal subroutines do because they can contain nested calls
-                if (regSaveOnStack)
-                    asmgen.restoreRegisterStack(CpuRegister.X, sub.shouldKeepA().saveOnReturn)
-                else
-                    asmgen.restoreRegisterLocal(CpuRegister.X)
-            } else
-                asmgen.restoreRegisterLocal(CpuRegister.X)
-        }
-    }
-
     internal fun optimizeIntArgsViaRegisters(sub: PtSub) =
         (sub.parameters.size==1 && sub.parameters[0].type in IntegerDatatypes)
                 || (sub.parameters.size==2 && sub.parameters[0].type in ByteDatatypes && sub.parameters[1].type in ByteDatatypes)
@@ -58,13 +26,13 @@ internal class FunctionCallAsmGen(private val program: PtProgram, private val as
         //       (you can use subroutine.shouldSaveX() and saveX()/restoreX() routines as a help for this)
 
         val symbol = asmgen.symbolTable.lookup(call.name)
-        val sub = symbol!!.astNode as IPtSubroutine
+        val sub = symbol?.astNode as IPtSubroutine
         val subAsmName = asmgen.asmSymbolName(call.name)
 
         if(sub is PtAsmSub) {
             argumentsViaRegisters(sub, call)
-            if (sub.inline && asmgen.options.optimize) {
-                // inline the subroutine.
+            if (sub.inline) {
+                // inline the subroutine. (regardless of optimization settings!)
                 // 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)
@@ -101,37 +69,59 @@ internal class FunctionCallAsmGen(private val program: PtProgram, private val as
         // remember: dealing with the X register and/or dealing with return values is the responsibility of the caller
     }
 
-    private fun argumentsViaRegisters(sub: PtAsmSub, call: PtFunctionCall) {
-        if(sub.parameters.size==1) {
-            argumentViaRegister(sub, IndexedValue(0, sub.parameters.single().second), call.args[0])
-        } else {
-            if(asmsub6502ArgsHaveRegisterClobberRisk(call.args, sub.parameters)) {
-                registerArgsViaCpuStackEvaluation(call, sub)
-            } else {
-                asmsub6502ArgsEvalOrder(sub).forEach {
-                    val param = sub.parameters[it]
-                    val arg = call.args[it]
-                    argumentViaRegister(sub, IndexedValue(it, param.second), arg)
-                }
+
+    private fun usesOtherRegistersWhileEvaluating(arg: PtExpression): Boolean {
+        return when(arg) {
+            is PtBuiltinFunctionCall -> {
+                if (arg.name == "lsb" || arg.name == "msb")
+                    return usesOtherRegistersWhileEvaluating(arg.args[0])
+                if (arg.name == "mkword")
+                    return usesOtherRegistersWhileEvaluating(arg.args[0]) || usesOtherRegistersWhileEvaluating(arg.args[1])
+                return !arg.isSimple()
             }
+            is PtAddressOf -> false
+            is PtIdentifier -> false
+            is PtMachineRegister -> false
+            is PtMemoryByte -> false
+            is PtNumber -> false
+            else -> true
         }
     }
 
-    private fun registerArgsViaCpuStackEvaluation(call: PtFunctionCall, callee: PtAsmSub) {
-        // 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.
+    private fun argumentsViaRegisters(sub: PtAsmSub, call: PtFunctionCall) {
+        val registersUsed = mutableListOf<RegisterOrStatusflag>();
 
-        if(callee.parameters.isEmpty())
-            return
+        fun usedA() = registersUsed.any {it.registerOrPair==RegisterOrPair.A || it.registerOrPair==RegisterOrPair.AX || it.registerOrPair==RegisterOrPair.AY}
+        fun usedX() = registersUsed.any {it.registerOrPair==RegisterOrPair.X || it.registerOrPair==RegisterOrPair.AX || it.registerOrPair==RegisterOrPair.XY}
+        fun usedY() = registersUsed.any {it.registerOrPair==RegisterOrPair.Y || it.registerOrPair==RegisterOrPair.AY || it.registerOrPair==RegisterOrPair.XY}
 
-        // use the cpu hardware stack as intermediate storage for the arguments.
-        val argOrder = asmsub6502ArgsEvalOrder(callee)
-        argOrder.reversed().forEach {
-            asmgen.pushCpuStack(callee.parameters[it].second.type, call.args[it])
-        }
-        argOrder.forEach {
-            val param = callee.parameters[it]
-            asmgen.popCpuStack(callee, param.second, param.first)
+        if(sub.parameters.size==1) {
+            argumentViaRegister(sub, IndexedValue(0, sub.parameters.single().second), call.args[0])
+        } else {
+            val optimalEvalOrder = asmsub6502ArgsEvalOrder(sub)
+            optimalEvalOrder.forEach {
+                val param = sub.parameters[it]
+                val arg = call.args[it]
+                registersUsed += if(usesOtherRegistersWhileEvaluating(arg)) {
+                    if(!registersUsed.any{it.statusflag!=null || it.registerOrPair in CpuRegisters})
+                        argumentViaRegister(sub, IndexedValue(it, param.second), arg)
+                    else if(registersUsed.any {it.statusflag!=null}) {
+                        throw AssemblyError("call argument evaluation problem: can't save cpu statusregister parameter ${call.position}")
+                    }
+                    else {
+                        if(usedX()) asmgen.saveRegisterStack(CpuRegister.X, false)
+                        if(usedY()) asmgen.saveRegisterStack(CpuRegister.Y, false)
+                        if(usedA()) asmgen.saveRegisterStack(CpuRegister.A, false)
+                        val used = argumentViaRegister(sub, IndexedValue(it, param.second), arg)
+                        if(usedA()) asmgen.restoreRegisterStack(CpuRegister.A, false)
+                        if(usedY()) asmgen.restoreRegisterStack(CpuRegister.Y, true)
+                        if(usedX()) asmgen.restoreRegisterStack(CpuRegister.X, true)
+                        used
+                    }
+                } else {
+                    argumentViaRegister(sub, IndexedValue(it, param.second), arg)
+                }
+            }
         }
     }
 
@@ -144,7 +134,7 @@ internal class FunctionCallAsmGen(private val program: PtProgram, private val as
         asmgen.assignExpressionToVariable(value, varName, parameter.type)
     }
 
-    private fun argumentViaRegister(sub: IPtSubroutine, parameter: IndexedValue<PtSubroutineParameter>, value: PtExpression, registerOverride: RegisterOrPair? = null) {
+    private fun argumentViaRegister(sub: IPtSubroutine, parameter: IndexedValue<PtSubroutineParameter>, value: PtExpression, registerOverride: RegisterOrPair? = null): RegisterOrStatusflag {
         // pass argument via a register parameter
         if(!isArgumentTypeCompatible(value.type, parameter.value.type))
             throw AssemblyError("argument type incompatible")
@@ -173,6 +163,7 @@ internal class FunctionCallAsmGen(private val program: PtProgram, private val as
                     }
                     is PtIdentifier -> {
                         val sourceName = asmgen.asmVariableName(value)
+                        // note: cannot use X register here to store A because it might be used for other arguments
                         asmgen.out("""
                             pha
                             clc
@@ -187,6 +178,7 @@ internal class FunctionCallAsmGen(private val program: PtProgram, private val as
                     }
                 }
             } else throw AssemblyError("can only use Carry as status flag parameter")
+            return RegisterOrStatusflag(null, statusflag)
         }
         else {
             // via register or register pair
@@ -219,6 +211,7 @@ internal class FunctionCallAsmGen(private val program: PtProgram, private val as
                 }
                 asmgen.translateNormalAssignment(AsmAssignment(src, target, program.memsizer, Position.DUMMY), scope)
             }
+            return RegisterOrStatusflag(register, null)
         }
     }
 
@@ -240,3 +233,5 @@ internal class FunctionCallAsmGen(private val program: PtProgram, private val as
         return false
     }
 }
+
+

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

@@ -1,9 +1,6 @@
 package prog8.codegen.cpu6502
 
-import prog8.code.ast.PtIdentifier
-import prog8.code.ast.PtNumber
-import prog8.code.ast.PtPostIncrDecr
-import prog8.code.ast.PtProgram
+import prog8.code.ast.*
 import prog8.code.core.*
 
 
@@ -13,7 +10,6 @@ internal class PostIncrDecrAsmGen(private val program: PtProgram, private val as
         val targetIdent = stmt.target.identifier
         val targetMemory = stmt.target.memory
         val targetArrayIdx = stmt.target.array
-        val scope = stmt.definingISub()
         when {
             targetIdent!=null -> {
                 val what = asmgen.asmVariableName(targetIdent)
@@ -38,6 +34,55 @@ internal class PostIncrDecrAsmGen(private val program: PtProgram, private val as
                 }
             }
             targetMemory!=null -> {
+                fun incDecViaExprEval() {
+                    asmgen.assignExpressionToRegister(targetMemory.address, RegisterOrPair.AY)
+                    asmgen.out("  sta  (+) + 1 |  sty  (+) + 2")
+                    if(incr)
+                        asmgen.out("+\tinc  ${'$'}ffff\t; modified")
+                    else
+                        asmgen.out("+\tdec  ${'$'}ffff\t; modified")
+                }
+
+                fun tryOptimizedPointerIncDec(address: PtBinaryExpression): Boolean {
+                    if(address.operator=="+") {
+                        val offset = address.right.asConstInteger()
+                        if(offset!=null && offset<256) {
+                            // we have @(ptr + 255) ++ , or  @(ptr+255)--
+                            asmgen.assignExpressionToRegister(address.left, RegisterOrPair.AY, false)
+                            asmgen.out("""
+                                sta  (+) + 1
+                                sty  (+) + 2
+                                ldx  #$offset""")
+                            if(incr)
+                                asmgen.out("+\tinc  ${'$'}ffff,x\t; modified")
+                            else
+                                asmgen.out("+\tdec  ${'$'}ffff,x\t; modified")
+                            return true
+                        } else if(address.right.type in ByteDatatypes) {
+                            // we have @(ptr + bytevar) ++ , or  @(ptr+bytevar)--
+                            asmgen.assignExpressionToRegister(address.left, RegisterOrPair.AY, false)
+                            asmgen.out(" sta  (+) + 1 |  sty  (+) + 2")
+                            asmgen.assignExpressionToRegister(address.right, RegisterOrPair.X, false)
+                            if(incr)
+                                asmgen.out("+\tinc  ${'$'}ffff,x\t; modified")
+                            else
+                                asmgen.out("+\tdec  ${'$'}ffff,x\t; modified")
+                            return true
+                        } else if((address.right as? PtTypeCast)?.value?.type in ByteDatatypes) {
+                            // we have @(ptr + bytevar) ++ , or  @(ptr+bytevar)--
+                            asmgen.assignExpressionToRegister(address.left, RegisterOrPair.AY, false)
+                            asmgen.out(" sta  (+) + 1 |  sty  (+) + 2")
+                            asmgen.assignExpressionToRegister((address.right as PtTypeCast).value, RegisterOrPair.X, false)
+                            if(incr)
+                                asmgen.out("+\tinc  ${'$'}ffff,x\t; modified")
+                            else
+                                asmgen.out("+\tdec  ${'$'}ffff,x\t; modified")
+                            return true
+                        }
+                    }
+                    return false
+                }
+
                 when (val addressExpr = targetMemory.address) {
                     is PtNumber -> {
                         val what = addressExpr.number.toHex()
@@ -51,13 +96,13 @@ internal class PostIncrDecrAsmGen(private val program: PtProgram, private val as
                         else
                             asmgen.out("+\tdec  ${'$'}ffff\t; modified")
                     }
+                    is PtBinaryExpression -> {
+                        if(!tryOptimizedPointerIncDec(addressExpr)) {
+                            incDecViaExprEval()
+                        }
+                    }
                     else -> {
-                        asmgen.assignExpressionToRegister(addressExpr, RegisterOrPair.AY)
-                        asmgen.out("  sta  (+) + 1 |  sty  (+) + 2")
-                        if(incr)
-                            asmgen.out("+\tinc  ${'$'}ffff\t; modified")
-                        else
-                            asmgen.out("+\tdec  ${'$'}ffff\t; modified")
+                        incDecViaExprEval()
                     }
                 }
             }
@@ -76,8 +121,7 @@ internal class PostIncrDecrAsmGen(private val program: PtProgram, private val as
         dec  ${asmArrayvarname}_msb+$constIndex
 +       dec  ${asmArrayvarname}_lsb+$constIndex""")
                     } else {
-                        asmgen.saveRegisterLocal(CpuRegister.X, scope!!)
-                        asmgen.loadScaledArrayIndexIntoRegister(targetArrayIdx, elementDt, CpuRegister.X)
+                        asmgen.loadScaledArrayIndexIntoRegister(targetArrayIdx, CpuRegister.X)
                         if(incr)
                             asmgen.out(" inc  ${asmArrayvarname}_lsb,x |  bne  + |  inc  ${asmArrayvarname}_msb,x |+")
                         else
@@ -86,14 +130,15 @@ internal class PostIncrDecrAsmGen(private val program: PtProgram, private val as
         bne  +
         dec  ${asmArrayvarname}_msb,x
 +       dec  ${asmArrayvarname}_lsb,x""")
-                        asmgen.restoreRegisterLocal(CpuRegister.X)
                     }
                     return
                 }
                 if(constIndex!=null) {
                     val indexValue = constIndex * program.memsizer.memorySize(elementDt)
                     when(elementDt) {
-                        in ByteDatatypes -> asmgen.out(if (incr) "  inc  $asmArrayvarname+$indexValue" else "  dec  $asmArrayvarname+$indexValue")
+                        in ByteDatatypes -> {
+                            asmgen.out(if (incr) "  inc  $asmArrayvarname+$indexValue" else "  dec  $asmArrayvarname+$indexValue")
+                        }
                         in WordDatatypes -> {
                             if(incr)
                                 asmgen.out(" inc  $asmArrayvarname+$indexValue |  bne  + |  inc  $asmArrayvarname+$indexValue+1 |+")
@@ -113,11 +158,10 @@ internal class PostIncrDecrAsmGen(private val program: PtProgram, private val as
                 }
                 else
                 {
-                    asmgen.saveRegisterLocal(CpuRegister.X, scope!!)
-                    asmgen.loadScaledArrayIndexIntoRegister(targetArrayIdx, elementDt, CpuRegister.X)
+                    asmgen.loadScaledArrayIndexIntoRegister(targetArrayIdx, CpuRegister.X)
                     when(elementDt) {
                         in ByteDatatypes -> {
-                            asmgen.out(if(incr) "  inc  $asmArrayvarname,x" else "  dec  $asmArrayvarname,x")
+                            asmgen.out(if (incr) "  inc  $asmArrayvarname,x" else "  dec  $asmArrayvarname,x")
                         }
                         in WordDatatypes -> {
                             if(incr)
@@ -127,8 +171,7 @@ internal class PostIncrDecrAsmGen(private val program: PtProgram, private val as
         lda  $asmArrayvarname,x
         bne  +
         dec  $asmArrayvarname+1,x
-+       dec  $asmArrayvarname,x 
-""")
++       dec  $asmArrayvarname,x""")
                         }
                         DataType.FLOAT -> {
                             asmgen.out("""
@@ -141,7 +184,6 @@ internal class PostIncrDecrAsmGen(private val program: PtProgram, private val as
                         }
                         else -> throw AssemblyError("weird array elt dt")
                     }
-                    asmgen.restoreRegisterLocal(CpuRegister.X)
                 }
             }
         }

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

@@ -34,8 +34,8 @@ internal class ProgramAndVarsGen(
         header()
         val allBlocks = program.allBlocks()
 
-        if(allBlocks.first().name != "p8_main" && allBlocks.first().name != "main")
-            throw AssemblyError("first block should be 'main' or 'p8_main'")
+        if(allBlocks.first().name != "p8b_main" && allBlocks.first().name != "main")
+            throw AssemblyError("first block should be 'main' or 'p8b_main'")
 
         if(errors.noErrors())  {
             program.allBlocks().forEach { block2asm(it) }
@@ -49,6 +49,7 @@ internal class ProgramAndVarsGen(
             }
 
             memorySlabs()
+            tempVars()
             footer()
         }
     }
@@ -75,8 +76,6 @@ internal class ProgramAndVarsGen(
         asmgen.out("P8ZP_SCRATCH_W1 = ${zp.SCRATCH_W1}    ; word")
         asmgen.out("P8ZP_SCRATCH_W2 = ${zp.SCRATCH_W2}    ; word")
         asmgen.out(".weak")   // hack to allow user to override the following two with command line redefinition (however, just use '-esa' command line option instead!)
-        asmgen.out("P8ESTACK_LO = ${compTarget.machine.ESTACK_LO.toHex()}")
-        asmgen.out("P8ESTACK_HI = ${compTarget.machine.ESTACK_HI.toHex()}")
         asmgen.out(".endweak")
 
         if(options.symbolDefs.isNotEmpty()) {
@@ -135,29 +134,22 @@ internal class ProgramAndVarsGen(
                 pha""")
         }
 
-        // make sure that on the cx16 and c64, basic rom is banked in again when we exit the program
         when(compTarget.name) {
             "cx16" -> {
                 if(options.floats)
                     asmgen.out("  lda  #4 |  sta  $01")    // to use floats, make sure Basic rom is banked in
-                asmgen.out("  jsr  p8_main.p8_start")
+                asmgen.out("  jsr  p8b_main.p8s_start")
                 asmgen.out("  jmp  sys.cleanup_at_exit")
             }
             "c64" -> {
-                asmgen.out("  jsr  p8_main.p8_start |  lda  #31 |  sta  $01")
-                if(!options.noSysInit)
-                    asmgen.out("  jmp  sys.cleanup_at_exit")
-                else
-                    asmgen.out("  rts")
+                asmgen.out("  jsr  p8b_main.p8s_start |  lda  #31 |  sta  $01")
+                asmgen.out("  jmp  sys.cleanup_at_exit")
             }
             "c128" -> {
-                asmgen.out("  jsr  p8_main.p8_start |  lda  #0 |  sta ${"$"}ff00")
-                if(!options.noSysInit)
-                    asmgen.out("  jmp  sys.cleanup_at_exit")
-                else
-                    asmgen.out("  rts")
+                asmgen.out("  jsr  p8b_main.p8s_start |  lda  #0 |  sta ${"$"}ff00")
+                asmgen.out("  jmp  sys.cleanup_at_exit")
             }
-            else -> asmgen.jmp("p8_main.p8_start")
+            else -> asmgen.jmp("p8b_main.p8s_start")
         }
     }
 
@@ -174,48 +166,119 @@ internal class ProgramAndVarsGen(
         }
     }
 
+    private fun tempVars() {
+        asmgen.out("; expression temp vars\n  .section BSS")
+        for((dt, count) in asmgen.tempVarsCounters) {
+            if(count>0) {
+                for(num in 1..count) {
+                    val name = asmgen.buildTempVarName(dt, num)
+                    when (dt) {
+                        DataType.BYTE  -> asmgen.out("$name    .char  ?")
+                        DataType.UBYTE -> asmgen.out("$name    .byte  ?")
+                        DataType.WORD  -> asmgen.out("$name    .sint  ?")
+                        DataType.UWORD -> asmgen.out("$name    .word  ?")
+                        DataType.FLOAT -> asmgen.out("$name    .fill  ${options.compTarget.machine.FLOAT_MEM_SIZE}")
+                        else -> throw AssemblyError("weird dt for extravar $dt")
+                    }
+                }
+            }
+        }
+        asmgen.out("  .send BSS")
+    }
+
     private fun footer() {
+        var relocateBssVars = false
+        var relocateBssSlabs = false
+        var relocatedBssStart = 0u
+        var relocatedBssEnd = 0u
+
+        if(options.varsGolden) {
+            if(options.compTarget.machine.BSSGOLDENRAM_START == 0u ||
+                options.compTarget.machine.BSSGOLDENRAM_END == 0u ||
+                options.compTarget.machine.BSSGOLDENRAM_END <= options.compTarget.machine.BSSGOLDENRAM_START) {
+                throw AssemblyError("current compilation target hasn't got the golden ram area properly defined or it is simply not available")
+            }
+            relocateBssVars = true
+            relocatedBssStart = options.compTarget.machine.BSSGOLDENRAM_START
+            relocatedBssEnd = options.compTarget.machine.BSSGOLDENRAM_END
+        }
+        else if(options.varsHighBank!=null) {
+            if(options.compTarget.machine.BSSHIGHRAM_START == 0u ||
+                options.compTarget.machine.BSSHIGHRAM_END == 0u ||
+                options.compTarget.machine.BSSHIGHRAM_END <= options.compTarget.machine.BSSHIGHRAM_START) {
+                throw AssemblyError("current compilation target hasn't got the high ram area properly defined or it is simply not available")
+            }
+            if(options.slabsHighBank!=null && options.varsHighBank!=options.slabsHighBank)
+                throw AssemblyError("slabs and vars high bank must be the same")
+            relocateBssVars = true
+            relocatedBssStart = options.compTarget.machine.BSSHIGHRAM_START
+            relocatedBssEnd = options.compTarget.machine.BSSHIGHRAM_END
+        }
+
+        if(options.slabsGolden) {
+            if(options.compTarget.machine.BSSGOLDENRAM_START == 0u ||
+                options.compTarget.machine.BSSGOLDENRAM_END == 0u ||
+                options.compTarget.machine.BSSGOLDENRAM_END <= options.compTarget.machine.BSSGOLDENRAM_START) {
+                throw AssemblyError("current compilation target hasn't got the golden ram area properly defined or it is simply not available")
+            }
+            relocateBssSlabs = true
+            relocatedBssStart = options.compTarget.machine.BSSGOLDENRAM_START
+            relocatedBssEnd = options.compTarget.machine.BSSGOLDENRAM_END
+        }
+        else if(options.slabsHighBank!=null) {
+            if(options.compTarget.machine.BSSHIGHRAM_START == 0u ||
+                options.compTarget.machine.BSSHIGHRAM_END == 0u ||
+                options.compTarget.machine.BSSHIGHRAM_END <= options.compTarget.machine.BSSHIGHRAM_START) {
+                throw AssemblyError("current compilation target hasn't got the high ram area properly defined or it is simply not available")
+            }
+            if(options.varsHighBank!=null && options.varsHighBank!=options.slabsHighBank)
+                throw AssemblyError("slabs and vars high bank must be the same")
+            relocateBssSlabs = true
+            relocatedBssStart = options.compTarget.machine.BSSHIGHRAM_START
+            relocatedBssEnd = options.compTarget.machine.BSSHIGHRAM_END
+        }
+
         asmgen.out("; bss sections")
         asmgen.out("PROG8_VARSHIGH_RAMBANK = ${options.varsHighBank ?: 1}")
-        if(options.varsHighBank!=null) {
-            if(options.compTarget.machine.BSSHIGHRAM_START == 0u || options.compTarget.machine.BSSHIGHRAM_END==0u) {
-                throw AssemblyError("current compilation target hasn't got the high ram area properly defined")
-            }
-            // BSS vars in high ram area, memory() slabs just concatenated at the end of the program.
-            if(symboltable.allMemorySlabs.isNotEmpty()) {
+        if(relocateBssVars) {
+            if(!relocateBssSlabs)
                 asmgen.out("  .dsection slabs_BSS")
-            }
             asmgen.out("prog8_program_end\t; end of program label for progend()")
-            asmgen.out("  * = ${options.compTarget.machine.BSSHIGHRAM_START.toHex()}")
+            asmgen.out("  * = ${relocatedBssStart.toHex()}")
             asmgen.out("prog8_bss_section_start")
             asmgen.out("  .dsection BSS")
-            asmgen.out("  .cerror * >= ${options.compTarget.machine.BSSHIGHRAM_END.toHex()}, \"too many variables for BSS section\"")
+            if(relocateBssSlabs)
+                asmgen.out("  .dsection slabs_BSS")
+            asmgen.out("  .cerror * > ${relocatedBssEnd.toHex()}, \"too many variables/data for BSS section\"")
             asmgen.out("prog8_bss_section_size = * - prog8_bss_section_start")
         } else {
-            // BSS vars followed by memory() slabs, concatenated at the end of the program.
             asmgen.out("prog8_bss_section_start")
             asmgen.out("  .dsection BSS")
             asmgen.out("prog8_bss_section_size = * - prog8_bss_section_start")
-            if(symboltable.allMemorySlabs.isNotEmpty()) {
+            if(!relocateBssSlabs)
                 asmgen.out("  .dsection slabs_BSS")
-            }
             asmgen.out("prog8_program_end\t; end of program label for progend()")
+            if(relocateBssSlabs) {
+                asmgen.out("  * = ${relocatedBssStart.toHex()}")
+                asmgen.out("  .dsection slabs_BSS")
+                asmgen.out("  .cerror * > ${relocatedBssEnd.toHex()}, \"too many data for slabs_BSS section\"")
+            }
         }
     }
 
     private fun block2asm(block: PtBlock) {
         asmgen.out("")
         asmgen.out("; ---- block: '${block.name}' ----")
-        if(block.address!=null)
-            asmgen.out("* = ${block.address!!.toHex()}")
+        if(block.options.address!=null)
+            asmgen.out("* = ${block.options.address!!.toHex()}")
         else {
-            if(block.alignment==PtBlock.BlockAlignment.WORD)
+            if(block.options.alignment==PtBlock.BlockAlignment.WORD)
                 asmgen.out("\t.align 2")
-            else if(block.alignment==PtBlock.BlockAlignment.PAGE)
+            else if(block.options.alignment==PtBlock.BlockAlignment.PAGE)
                 asmgen.out("\t.align $100")
         }
 
-        asmgen.out("${block.name}\t" + (if(block.forceOutput) ".block" else ".proc"))
+        asmgen.out("${block.name}\t" + (if(block.options.forceOutput) ".block" else ".proc"))
         asmgen.outputSourceLine(block)
 
         createBlockVariables(block)
@@ -238,7 +301,7 @@ internal class ProgramAndVarsGen(
             asmgen.out("  rts\n  .bend")
         }
 
-        asmgen.out(if(block.forceOutput) "\n\t.bend" else "\n\t.pend")
+        asmgen.out(if(block.options.forceOutput) "\n\t.bend" else "\n\t.pend")
     }
 
     private fun getVars(scope: StNode): Map<String, StNode> =
@@ -271,16 +334,14 @@ internal class ProgramAndVarsGen(
 
     internal fun translateAsmSubroutine(sub: PtAsmSub) {
         if(sub.inline) {
-            if(options.optimize) {
-                return
-            }
+            return      // subroutine gets inlined at call site.
         }
 
         asmgen.out("")
 
         val asmStartScope: String
         val asmEndScope: String
-        if(sub.definingBlock()!!.forceOutput) {
+        if(sub.definingBlock()!!.options.forceOutput) {
             asmStartScope = ".block"
             asmEndScope = ".bend"
         } else {
@@ -303,7 +364,7 @@ internal class ProgramAndVarsGen(
 
         val asmStartScope: String
         val asmEndScope: String
-        if(sub.definingBlock()!!.forceOutput) {
+        if(sub.definingBlock()!!.options.forceOutput) {
             asmStartScope = ".block"
             asmEndScope = ".bend"
         } else {
@@ -335,7 +396,7 @@ internal class ProgramAndVarsGen(
         asmsubs2asm(sub.children)
 
         // the main.start subroutine is the program's entrypoint and should perform some initialization logic
-        if((sub.name=="start" || sub.name=="p8_start") && (sub.definingBlock()!!.name=="main" || sub.definingBlock()!!.name=="p8_main"))
+        if((sub.name=="start" || sub.name=="p8s_start") && (sub.definingBlock()!!.name=="main" || sub.definingBlock()!!.name=="p8b_main"))
             entrypointInitialization()
 
         if(functioncallAsmGen.optimizeIntArgsViaRegisters(sub)) {
@@ -373,12 +434,6 @@ internal class ProgramAndVarsGen(
                 else -> throw AssemblyError("weird dt for extravar $dt")
             }
         }
-        if(asmGenInfo.usedRegsaveA)      // will probably never occur
-            asmgen.out("prog8_regsaveA     .byte  ?")
-        if(asmGenInfo.usedRegsaveX)
-            asmgen.out("prog8_regsaveX     .byte  ?")
-        if(asmGenInfo.usedRegsaveY)
-            asmgen.out("prog8_regsaveY     .byte  ?")
         if(asmGenInfo.usedFloatEvalResultVar1)
             asmgen.out("$subroutineFloatEvalResultVar1    .fill  ${options.compTarget.machine.FLOAT_MEM_SIZE}")
         if(asmGenInfo.usedFloatEvalResultVar2)
@@ -438,12 +493,12 @@ internal class ProgramAndVarsGen(
                 asmgen.out("""
                     lda  #<${name}_init_value
                     ldy  #>${name}_init_value
-                    sta  cx16.r0L
-                    sty  cx16.r0H
+                    sta  cx16.r0
+                    sty  cx16.r0+1
                     lda  #<${name}
                     ldy  #>${name}
-                    sta  cx16.r1L
-                    sty  cx16.r1H
+                    sta  cx16.r1
+                    sty  cx16.r1+1
                     lda  #<$size
                     ldy  #>$size
                     jsr  sys.memcopy""")
@@ -462,7 +517,6 @@ internal class ProgramAndVarsGen(
         }
 
         asmgen.out("""+        
-                    ldx  #127       ; init estack ptr (half page)
                     clv
                     clc""")
     }
@@ -508,7 +562,15 @@ internal class ProgramAndVarsGen(
         for ((scopedName, zpvar) in zpVariables) {
             if (scopedName.startsWith("cx16.r"))
                 continue        // The 16 virtual registers of the cx16 are not actual variables in zp, they're memory mapped
-            asmgen.out("${scopedName.substringAfterLast('.')} \t= ${zpvar.address} \t; zp ${zpvar.dt}")
+            val variable = symboltable.flat.getValue(scopedName) as StStaticVariable
+            if(variable.dt in SplitWordArrayTypes) {
+                val lsbAddr = zpvar.address
+                val msbAddr = zpvar.address + (zpvar.size/2).toUInt()
+                asmgen.out("${scopedName.substringAfterLast('.')}_lsb \t= $lsbAddr \t; zp ${zpvar.dt} (lsbs)")
+                asmgen.out("${scopedName.substringAfterLast('.')}_msb \t= $msbAddr \t; zp ${zpvar.dt} (msbs)")
+            } else {
+                asmgen.out("${scopedName.substringAfterLast('.')} \t= ${zpvar.address} \t; zp ${zpvar.dt}")
+            }
         }
     }
 

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

@@ -0,0 +1,253 @@
+package prog8.codegen.cpu6502.assignment
+
+import prog8.code.ast.PtBinaryExpression
+import prog8.code.ast.PtExpression
+import prog8.code.core.*
+import prog8.code.target.C64Target
+import prog8.code.target.Cx16Target
+import prog8.codegen.cpu6502.AsmGen6502Internal
+
+//
+// This contains codegen for stack-based evaluation of binary expressions.
+// It uses the CPU stack so depth is limited.
+// It is called "as a last resort" if the optimized codegen path is unable
+// to come up with a special case of the expression.
+//
+internal class AnyExprAsmGen(
+    private val asmgen: AsmGen6502Internal
+) {
+    fun assignAnyExpressionUsingStack(expr: PtBinaryExpression, assign: AsmAssignment): Boolean {
+        when(expr.type) {
+            in ByteDatatypes -> {
+                if(expr.left.type in ByteDatatypes && expr.right.type in ByteDatatypes)
+                    return assignByteBinExpr(expr, assign)
+                if (expr.left.type in WordDatatypes && expr.right.type in WordDatatypes) {
+                    require(expr.operator in ComparisonOperators)
+                    throw AssemblyError("words operands comparison -> byte, should have been handled by assignOptimizedComparisonWords()")
+                }
+                if (expr.left.type==DataType.FLOAT && expr.right.type==DataType.FLOAT) {
+                    require(expr.operator in ComparisonOperators)
+                    return assignFloatBinExpr(expr, assign)
+                }
+                throw AssemblyError("weird expr operand types: ${expr.left.type} and ${expr.right.type}")
+            }
+            in WordDatatypes -> {
+                require(expr.left.type in WordDatatypes && expr.right.type in WordDatatypes) {
+                    "both operands must be words"
+                }
+                return assignWordBinExpr(expr)
+            }
+            DataType.FLOAT -> {
+                require(expr.left.type==DataType.FLOAT && expr.right.type==DataType.FLOAT) {
+                    "both operands must be floats"
+                }
+                return assignFloatBinExpr(expr, assign)
+            }
+            else -> throw AssemblyError("weird expression type in assignment")
+        }
+    }
+
+    private fun assignWordBinExpr(expr: PtBinaryExpression): Boolean {
+        when(expr.operator) {
+            "+" -> TODO("word + at ${expr.position}")
+            "-" -> TODO("word - at ${expr.position}")
+            "*" -> TODO("word * at ${expr.position}")
+            "/" -> TODO("word / at ${expr.position}")
+            "<<" -> TODO("word << at ${expr.position}")
+            ">>" -> TODO("word >> at ${expr.position}")
+            "%" -> TODO("word % at ${expr.position}")
+            "and" -> TODO("word logical and (with optional shortcircuit) ${expr.position}")
+            "or" -> TODO("word logical or (with optional shortcircuit) ${expr.position}")
+            "&" -> TODO("word and at ${expr.position}")
+            "|" -> TODO("word or at ${expr.position}")
+            "^", "xor" -> TODO("word xor at ${expr.position}")
+            "==" -> TODO("word == at ${expr.position}")
+            "!=" -> TODO("word != at ${expr.position}")
+            "<" -> TODO("word < at ${expr.position}")
+            "<=" -> TODO("word <= at ${expr.position}")
+            ">" -> TODO("word > at ${expr.position}")
+            ">=" -> TODO("word >= at ${expr.position}")
+            else -> return false
+        }
+    }
+
+    private fun assignByteBinExpr(expr: PtBinaryExpression, assign: AsmAssignment): Boolean {
+        when(expr.operator) {
+            "+" -> {
+                asmgen.assignExpressionToRegister(expr.left, RegisterOrPair.A, false)
+                asmgen.out("  pha")
+                asmgen.assignExpressionToVariable(expr.right, "P8ZP_SCRATCH_B1", DataType.UBYTE)
+                asmgen.out("  pla |  clc |  adc  P8ZP_SCRATCH_B1")
+                asmgen.assignRegister(RegisterOrPair.A, assign.target)
+                return true
+            }
+            "-" -> {
+                asmgen.assignExpressionToRegister(expr.left, RegisterOrPair.A, false)
+                asmgen.out("  pha")
+                asmgen.assignExpressionToVariable(expr.right, "P8ZP_SCRATCH_B1", DataType.UBYTE)
+                asmgen.out("  pla |  sec |  sbc  P8ZP_SCRATCH_B1")
+                asmgen.assignRegister(RegisterOrPair.A, assign.target)
+                return true
+            }
+            "*" -> {
+                TODO("byte * at ${expr.position}")
+            }
+            "/" -> {
+                TODO("byte / at ${expr.position}")
+            }
+            "<<" -> {
+                TODO("byte << at ${expr.position}")
+            }
+            ">>" -> {
+                TODO("byte >> at ${expr.position}")
+            }
+            "%" -> {
+                TODO("byte % at ${expr.position}")
+            }
+            "and" -> TODO("logical and (with optional shortcircuit) ${expr.position}")
+            "or" -> TODO("logical or (with optional shortcircuit) ${expr.position}")
+            "&" -> {
+                asmgen.assignExpressionToRegister(expr.left, RegisterOrPair.A, false)
+                asmgen.out("  pha")
+                asmgen.assignExpressionToVariable(expr.right, "P8ZP_SCRATCH_B1", DataType.UBYTE)
+                asmgen.out("  pla |  and  P8ZP_SCRATCH_B1")
+                asmgen.assignRegister(RegisterOrPair.A, assign.target)
+                return true
+            }
+            "|" -> {
+                asmgen.assignExpressionToRegister(expr.left, RegisterOrPair.A, false)
+                asmgen.out("  pha")
+                asmgen.assignExpressionToVariable(expr.right, "P8ZP_SCRATCH_B1", DataType.UBYTE)
+                asmgen.out("  pla |  ora  P8ZP_SCRATCH_B1")
+                asmgen.assignRegister(RegisterOrPair.A, assign.target)
+                return true
+            }
+            "^", "xor" -> {
+                asmgen.assignExpressionToRegister(expr.left, RegisterOrPair.A, false)
+                asmgen.out("  pha")
+                asmgen.assignExpressionToVariable(expr.right, "P8ZP_SCRATCH_B1", DataType.UBYTE)
+                asmgen.out("  pla |  eor  P8ZP_SCRATCH_B1")
+                asmgen.assignRegister(RegisterOrPair.A, assign.target)
+                return true
+            }
+            "==" -> {
+                TODO("byte == at ${expr.position}")
+            }
+            "!=" -> {
+                TODO("byte != at ${expr.position}")
+            }
+            "<" -> {
+                TODO("byte < at ${expr.position}")
+            }
+            "<=" -> {
+                TODO("byte <= at ${expr.position}")
+            }
+            ">" -> {
+                TODO("byte > at ${expr.position}")
+            }
+            ">=" -> {
+                TODO("byte >= at ${expr.position}")
+            }
+            else -> return false
+        }
+    }
+
+    private fun assignFloatBinExpr(expr: PtBinaryExpression, assign: AsmAssignment): Boolean {
+        when(expr.operator) {
+            "+" -> {
+                assignFloatOperandsToFACandARG(expr.left, expr.right)
+                asmgen.out("  jsr  floats.FADDT")
+                asmgen.assignRegister(RegisterOrPair.FAC1, assign.target)
+                return true
+            }
+            "-" -> {
+                assignFloatOperandsToFACandARG(expr.right, expr.left)
+                asmgen.out("  jsr  floats.FSUBT")
+                asmgen.assignRegister(RegisterOrPair.FAC1, assign.target)
+                return true
+            }
+            "*" -> {
+                assignFloatOperandsToFACandARG(expr.left, expr.right)
+                asmgen.out("  jsr  floats.FMULTT")
+                asmgen.assignRegister(RegisterOrPair.FAC1, assign.target)
+                return true
+            }
+            "/" -> {
+                assignFloatOperandsToFACandARG(expr.right, expr.left)
+                asmgen.out("  jsr  floats.FDIVT")
+                asmgen.assignRegister(RegisterOrPair.FAC1, assign.target)
+                return true
+            }
+            "==" -> {
+                setupFloatComparisonFAC1vsVarAY(expr)
+                asmgen.out("  jsr  floats.var_fac1_equal_f")
+                asmgen.assignRegister(RegisterOrPair.A, assign.target)
+                return true
+            }
+            "!=" -> {
+                setupFloatComparisonFAC1vsVarAY(expr)
+                asmgen.out("  jsr  floats.var_fac1_notequal_f")
+                asmgen.assignRegister(RegisterOrPair.A, assign.target)
+                return true
+            }
+            "<" -> {
+                setupFloatComparisonFAC1vsVarAY(expr)
+                asmgen.out("  jsr  floats.var_fac1_less_f")
+                asmgen.assignRegister(RegisterOrPair.A, assign.target)
+                return true
+            }
+            ">" -> {
+                setupFloatComparisonFAC1vsVarAY(expr)
+                asmgen.out("  jsr  floats.var_fac1_greater_f")
+                asmgen.assignRegister(RegisterOrPair.A, assign.target)
+                return true
+            }
+            "<=" -> {
+                setupFloatComparisonFAC1vsVarAY(expr)
+                asmgen.out("  jsr  floats.var_fac1_lesseq_f")
+                asmgen.assignRegister(RegisterOrPair.A, assign.target)
+                return true
+            }
+            ">=" -> {
+                setupFloatComparisonFAC1vsVarAY(expr)
+                asmgen.out("  jsr  floats.var_fac1_greatereq_f")
+                asmgen.assignRegister(RegisterOrPair.A, assign.target)
+                return true
+            }
+            else -> TODO("float expression operator ${expr.operator}")
+        }
+    }
+
+    private fun assignFloatOperandsToFACandARG(left: PtExpression, right: PtExpression) {
+        when(asmgen.options.compTarget.name) {
+            C64Target.NAME -> {
+                // c64 has a quirk: always make sure FAC2 is loaded last (done using CONUPK)  otherwise the result will be corrupt on C64
+                // this requires some more forced copying around of float values in certain cases
+                if (right.isSimple()) {
+                    asmgen.assignExpressionToRegister(left, RegisterOrPair.FAC1, true)
+                    asmgen.assignExpressionToRegister(right, RegisterOrPair.FAC2, true)
+                } else {
+                    asmgen.assignExpressionToRegister(right, RegisterOrPair.FAC1, true)
+                    asmgen.pushFAC1()
+                    asmgen.assignExpressionToRegister(left, RegisterOrPair.FAC1, true)
+                    asmgen.popFAC2()
+                }
+            }
+            Cx16Target.NAME -> {
+                asmgen.assignExpressionToRegister(left, RegisterOrPair.FAC1, true)
+                if (!right.isSimple()) asmgen.pushFAC1()
+                asmgen.assignExpressionToRegister(right, RegisterOrPair.FAC2, true)
+                if (!right.isSimple()) asmgen.popFAC1()
+            }
+            else -> TODO("don't know how to evaluate float expression for selected compilation target")
+        }
+    }
+
+    private fun setupFloatComparisonFAC1vsVarAY(expr: PtBinaryExpression) {
+        asmgen.assignExpressionToRegister(expr.left, RegisterOrPair.FAC1, true)
+        if(!expr.right.isSimple()) asmgen.pushFAC1()
+        asmgen.assignExpressionToVariable(expr.right, "floats.floats_temp_var", DataType.FLOAT)
+        if(!expr.right.isSimple()) asmgen.popFAC1()
+        asmgen.out("  lda  #<floats.floats_temp_var |  ldy  #>floats.floats_temp_var")
+    }
+}

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

@@ -10,8 +10,7 @@ internal enum class TargetStorageKind {
     VARIABLE,
     ARRAY,
     MEMORY,
-    REGISTER,
-    STACK
+    REGISTER
 }
 
 internal enum class SourceStorageKind {
@@ -20,7 +19,6 @@ internal enum class SourceStorageKind {
     ARRAY,
     MEMORY,
     REGISTER,
-    STACK,              // value is already present on stack
     EXPRESSION,         // expression in ast-form, still to be evaluated
 }
 
@@ -120,7 +118,7 @@ internal class AsmAssignTarget(val kind: TargetStorageKind,
             TargetStorageKind.MEMORY -> {
                 left isSameAs memory!!
             }
-            TargetStorageKind.REGISTER, TargetStorageKind.STACK -> {
+            TargetStorageKind.REGISTER -> {
                 false
             }
         }

codeGenCpu6502/test/Dummies.kt

@@ -18,6 +18,8 @@ internal object DummyMemsizer : IMemSizer {
 }
 
 internal object DummyStringEncoder : IStringEncoding {
+    override val defaultEncoding: Encoding = Encoding.ISO
+
     override fun encodeString(str: String, encoding: Encoding): List<UByte> {
         return emptyList()
     }
@@ -27,11 +29,11 @@ internal object DummyStringEncoder : IStringEncoding {
     }
 }
 
-internal class ErrorReporterForTests(private val throwExceptionAtReportIfErrors: Boolean=true, private val keepMessagesAfterReporting: Boolean=false):
-    IErrorReporter {
+internal class ErrorReporterForTests(private val throwExceptionAtReportIfErrors: Boolean=true, private val keepMessagesAfterReporting: Boolean=false): IErrorReporter {
 
     val errors = mutableListOf<String>()
     val warnings = mutableListOf<String>()
+    val infos = mutableListOf<String>()
 
     override fun err(msg: String, position: Position) {
         val text = "${position.toClickableStr()} $msg"
@@ -45,6 +47,12 @@ internal class ErrorReporterForTests(private val throwExceptionAtReportIfErrors:
             warnings.add(text)
     }
 
+    override fun info(msg: String, position: Position) {
+        val text = "${position.toClickableStr()} $msg"
+        if(text !in infos)
+            infos.add(text)
+    }
+
     override fun undefined(symbol: List<String>, position: Position) {
         err("undefined symbol: ${symbol.joinToString(".")}", position)
     }
@@ -52,10 +60,11 @@ internal class ErrorReporterForTests(private val throwExceptionAtReportIfErrors:
     override fun noErrors(): Boolean  = errors.isEmpty()
 
     override fun report() {
+        infos.forEach { println("UNITTEST COMPILATION REPORT: INFO: $it") }
         warnings.forEach { println("UNITTEST COMPILATION REPORT: WARNING: $it") }
         errors.forEach { println("UNITTEST COMPILATION REPORT: ERROR: $it") }
         if(throwExceptionAtReportIfErrors)
-            finalizeNumErrors(errors.size, warnings.size)
+            finalizeNumErrors(errors.size, warnings.size, infos.size)
         if(!keepMessagesAfterReporting) {
             clear()
         }
@@ -64,5 +73,6 @@ internal class ErrorReporterForTests(private val throwExceptionAtReportIfErrors:
     fun clear() {
         errors.clear()
         warnings.clear()
+        infos.clear()
     }
 }

codeGenCpu6502/test/TestCodegen.kt

@@ -22,6 +22,7 @@ class TestCodegen: FunSpec({
             CbmPrgLauncherType.NONE,
             ZeropageType.DONTUSE,
             zpReserved = emptyList(),
+            zpAllowed = CompilationOptions.AllZeropageAllowed,
             floats = true,
             noSysInit = false,
             compTarget = target,
@@ -44,7 +45,7 @@ class TestCodegen: FunSpec({
 //}
         val codegen = AsmGen6502(prefixSymbols = false)
         val program = PtProgram("test", DummyMemsizer, DummyStringEncoder)
-        val block = PtBlock("main", null, false, false, false, PtBlock.BlockAlignment.NONE, SourceCode.Generated("test"), Position.DUMMY)
+        val block = PtBlock("main",false, SourceCode.Generated("test"), PtBlock.Options(), Position.DUMMY)
         val sub = PtSub("start", emptyList(), null, Position.DUMMY)
         sub.add(PtVariable("pi", DataType.UBYTE, ZeropageWish.DONTCARE, PtNumber(DataType.UBYTE, 0.0, Position.DUMMY), null, Position.DUMMY))
         sub.add(PtVariable("particleX", DataType.ARRAY_UB, ZeropageWish.DONTCARE, null, 3u, Position.DUMMY))
@@ -94,7 +95,7 @@ class TestCodegen: FunSpec({
         program.add(block)
 
         // define the "cx16.r0" virtual register
-        val cx16block = PtBlock("cx16", null, false, false, false, PtBlock.BlockAlignment.NONE, SourceCode.Generated("test"), Position.DUMMY)
+        val cx16block = PtBlock("cx16", false, SourceCode.Generated("test"), PtBlock.Options(), Position.DUMMY)
         cx16block.add(PtMemMapped("r0", DataType.UWORD, 100u, null, Position.DUMMY))
         program.add(cx16block)
 
@@ -106,7 +107,7 @@ class TestCodegen: FunSpec({
         Files.deleteIfExists(Path("${result.name}.asm"))
     }
 
-    test("64tass assembler available? - if this fails you need to install 64tass in the path") {
+    test("64tass assembler available? - if this fails you need to install 64tass version 1.58 or newer in the path") {
         val command = mutableListOf("64tass", "--version")
         shouldNotThrowAny {
             val proc = ProcessBuilder(command).start()

codeGenExperimental/build.gradle

@@ -36,10 +36,10 @@ dependencies {
 sourceSets {
     main {
         java {
-            srcDirs = ["${project.projectDir}/src"]
+            srcDir "${project.projectDir}/src"
         }
         resources {
-            srcDirs = ["${project.projectDir}/res"]
+            srcDir "${project.projectDir}/res"
         }
     }
 }

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

@@ -15,7 +15,7 @@ class ExperiCodeGen: ICodeGeneratorBackend {
         symbolTable: SymbolTable,
         options: CompilationOptions,
         errors: IErrorReporter
-    ): IAssemblyProgram? {
+    ): IAssemblyProgram {
 
         // you could write a code generator directly on the PtProgram AST,
         // but you can also use the Intermediate Representation to build a codegen on:

codeGenIntermediate/build.gradle

@@ -30,16 +30,16 @@ dependencies {
     // implementation "org.jetbrains.kotlin:kotlin-reflect"
     implementation "com.michael-bull.kotlin-result:kotlin-result-jvm:1.1.18"
 
-    testImplementation 'io.kotest:kotest-runner-junit5-jvm:5.6.2'
+    testImplementation 'io.kotest:kotest-runner-junit5-jvm:5.8.0'
 }
 
 sourceSets {
     main {
         java {
-            srcDirs = ["${project.projectDir}/src"]
+            srcDir "${project.projectDir}/src"
         }
         resources {
-            srcDirs = ["${project.projectDir}/res"]
+            srcDir "${project.projectDir}/res"
         }
     }
     test {

codeGenIntermediate/codeGenIntermediate.iml

@@ -14,5 +14,6 @@
     <orderEntry type="module" module-name="intermediate" />
     <orderEntry type="library" name="io.kotest.assertions.core.jvm" level="project" />
     <orderEntry type="library" name="io.kotest.runner.junit5.jvm" level="project" />
+    <orderEntry type="library" name="michael.bull.kotlin.result.jvm" level="project" />
   </component>
 </module>

codeGenIntermediate/src/prog8/codegen/intermediate/AssignmentGen.kt

@@ -1,110 +1,79 @@
 package prog8.codegen.intermediate
 
+import com.github.michaelbull.result.Ok
+import com.github.michaelbull.result.Result
+import com.github.michaelbull.result.getOrElse
 import prog8.code.ast.*
-import prog8.code.core.AssemblyError
-import prog8.code.core.DataType
-import prog8.code.core.PrefixOperators
-import prog8.code.core.SignedDatatypes
+import prog8.code.core.*
 import prog8.intermediate.*
 
+
 internal class AssignmentGen(private val codeGen: IRCodeGen, private val expressionEval: ExpressionGen) {
 
     internal fun translate(assignment: PtAssignment): IRCodeChunks {
         if(assignment.target.children.single() is PtMachineRegister)
             throw AssemblyError("assigning to a register should be done by just evaluating the expression into resultregister")
 
-        return translateRegularAssign(assignment)
+        val chunks = translateRegularAssign(assignment)
+        chunks.filterIsInstance<IRCodeChunk>().firstOrNull()?.appendSrcPosition(assignment.position)
+        return chunks
     }
 
     internal fun translate(augAssign: PtAugmentedAssign): IRCodeChunks {
         if(augAssign.target.children.single() is PtMachineRegister)
             throw AssemblyError("assigning to a register should be done by just evaluating the expression into resultregister")
 
-        val ident = augAssign.target.identifier
-        val memory = augAssign.target.memory
-        val array = augAssign.target.array
+        val target = augAssign.target
+        val targetDt = irType(target.type)
+        val memTarget = target.memory
+        val constAddress = (memTarget?.address as? PtNumber)?.number?.toInt()
+        val symbol = target.identifier?.name
+        val array = target.array
+        val value = augAssign.value
+        val signed = target.type in SignedDatatypes
+        val result: Result<IRCodeChunks, NotImplementedError> = when(augAssign.operator) {
+            "+=" -> expressionEval.operatorPlusInplace(symbol, array, constAddress, memTarget, targetDt, value)
+            "-=" -> expressionEval.operatorMinusInplace(symbol, array, constAddress, memTarget, targetDt, value)
+            "*=" -> expressionEval.operatorMultiplyInplace(symbol, array, constAddress, memTarget, targetDt, value)
+            "/=" -> expressionEval.operatorDivideInplace(symbol, array, constAddress, memTarget, targetDt, value, signed)
+            "|=" -> expressionEval.operatorOrInplace(symbol, array, constAddress, memTarget, targetDt, value)
+            "or=" -> expressionEval.operatorLogicalOrInplace(symbol, array, constAddress, memTarget, targetDt, value)
+            "&=" -> expressionEval.operatorAndInplace(symbol, array, constAddress, memTarget, targetDt, value)
+            "and=" -> expressionEval.operatorLogicalAndInplace(symbol, array, constAddress, memTarget, targetDt, value)
+            "^=", "xor=" -> expressionEval.operatorXorInplace(symbol, array, constAddress, memTarget, targetDt, value)
+            "<<=" -> expressionEval.operatorShiftLeftInplace(symbol, array, constAddress, memTarget, targetDt, value)
+            ">>=" -> expressionEval.operatorShiftRightInplace(symbol, array, constAddress, memTarget, targetDt, value, signed)
+            "%=" -> expressionEval.operatorModuloInplace(symbol, array, constAddress, memTarget, targetDt, value)
+            "==" -> expressionEval.operatorEqualsInplace(symbol, array, constAddress, memTarget, targetDt, value)
+            "!=" -> expressionEval.operatorNotEqualsInplace(symbol, array, constAddress, memTarget, targetDt, value)
+            "<" -> expressionEval.operatorLessInplace(symbol, array, constAddress, memTarget, targetDt, value, signed)
+            ">" -> expressionEval.operatorGreaterInplace(symbol, array, constAddress, memTarget, targetDt, value, signed)
+            "<=" -> expressionEval.operatorLessEqualInplace(symbol, array, constAddress, memTarget, targetDt, value, signed)
+            ">=" -> expressionEval.operatorGreaterEqualInplace(symbol, array, constAddress, memTarget, targetDt, value, signed)
+            in PrefixOperators -> inplacePrefix(augAssign.operator, symbol, array, constAddress, memTarget, targetDt)
 
-        return if(ident!=null) {
-            assignVarAugmented(ident.name, augAssign)
-        } else if(memory != null) {
-            if(memory.address is PtNumber)
-                assignMemoryAugmented((memory.address as PtNumber).number.toInt(), augAssign)
-            else
-                fallbackAssign(augAssign)
-        } else if(array!=null) {
-            // NOTE: naive fallback assignment here will sometimes generate code that loads the index value multiple times
-            // in a register. It's way too much work to optimize that here - instead, we trust that the generated IL assembly
-            // will be optimized later and have the double assignments removed.
-            fallbackAssign(augAssign)
-        } else {
-            fallbackAssign(augAssign)
+            else -> throw AssemblyError("invalid augmented assign operator ${augAssign.operator}")
         }
-    }
 
-    private fun assignMemoryAugmented(
-        address: Int,
-        assignment: PtAugmentedAssign
-    ): IRCodeChunks {
-        val value = assignment.value
-        val vmDt = irType(value.type)
-        return when(assignment.operator) {
-            "+" -> expressionEval.operatorPlusInplace(address, null, vmDt, value)
-            "-" -> expressionEval.operatorMinusInplace(address, null, vmDt, value)
-            "*" -> expressionEval.operatorMultiplyInplace(address, null, vmDt, value)
-            "/" -> expressionEval.operatorDivideInplace(address, null, vmDt, value.type in SignedDatatypes, value)
-            "|" -> expressionEval.operatorOrInplace(address, null, vmDt, value)
-            "&" -> expressionEval.operatorAndInplace(address, null, vmDt, value)
-            "^" -> expressionEval.operatorXorInplace(address, null, vmDt, value)
-            "<<" -> expressionEval.operatorShiftLeftInplace(address, null, vmDt, value)
-            ">>" -> expressionEval.operatorShiftRightInplace(address, null, vmDt, value.type in SignedDatatypes, value)
-            "%=" -> expressionEval.operatorModuloInplace(address, null, vmDt, value)
-            "==" -> expressionEval.operatorEqualsInplace(address, null, vmDt, value)
-            "!=" -> expressionEval.operatorNotEqualsInplace(address, null, vmDt, value)
-            "<" -> expressionEval.operatorLessInplace(address, null, vmDt, value.type in SignedDatatypes, value)
-            ">" -> expressionEval.operatorGreaterInplace(address, null, vmDt, value.type in SignedDatatypes, value)
-            "<=" -> expressionEval.operatorLessEqualInplace(address, null, vmDt, value.type in SignedDatatypes, value)
-            ">=" -> expressionEval.operatorGreaterEqualInplace(address, null, vmDt, value.type in SignedDatatypes, value)
-            in PrefixOperators -> inplacePrefix(assignment.operator, vmDt, address, null)
-
-            else -> throw AssemblyError("invalid augmented assign operator ${assignment.operator}")
-        }
-    }
-
-    private fun assignVarAugmented(symbol: String, assignment: PtAugmentedAssign): IRCodeChunks {
-        val value = assignment.value
-        val targetDt = irType(assignment.target.type)
-        return when (assignment.operator) {
-            "+=" -> expressionEval.operatorPlusInplace(null, symbol, targetDt, value)
-            "-=" -> expressionEval.operatorMinusInplace(null, symbol, targetDt, value)
-            "*=" -> expressionEval.operatorMultiplyInplace(null, symbol, targetDt, value)
-            "/=" -> expressionEval.operatorDivideInplace(null, symbol, targetDt, value.type in SignedDatatypes, value)
-            "|=" -> expressionEval.operatorOrInplace(null, symbol, targetDt, value)
-            "&=" -> expressionEval.operatorAndInplace(null, symbol, targetDt, value)
-            "^=" -> expressionEval.operatorXorInplace(null, symbol, targetDt, value)
-            "<<=" -> expressionEval.operatorShiftLeftInplace(null, symbol, targetDt, value)
-            ">>=" -> expressionEval.operatorShiftRightInplace(null, symbol, targetDt, value.type in SignedDatatypes, value)
-            "%=" -> expressionEval.operatorModuloInplace(null, symbol, targetDt, value)
-            "==" -> expressionEval.operatorEqualsInplace(null, symbol, targetDt, value)
-            "!=" -> expressionEval.operatorNotEqualsInplace(null, symbol, targetDt, value)
-            "<" -> expressionEval.operatorLessInplace(null, symbol, targetDt, value.type in SignedDatatypes, value)
-            ">" -> expressionEval.operatorGreaterInplace(null, symbol, targetDt, value.type in SignedDatatypes, value)
-            "<=" -> expressionEval.operatorLessEqualInplace(null, symbol, targetDt, value.type in SignedDatatypes, value)
-            ">=" -> expressionEval.operatorGreaterEqualInplace(null, symbol, targetDt, value.type in SignedDatatypes, value)
-            in PrefixOperators -> inplacePrefix(assignment.operator, targetDt, null, symbol)
-            else -> throw AssemblyError("invalid augmented assign operator ${assignment.operator}")
-        }
+        val chunks = result.getOrElse { fallbackAssign(augAssign) }
+        chunks.filterIsInstance<IRCodeChunk>().firstOrNull()?.appendSrcPosition(augAssign.position)
+        return chunks
     }
 
     private fun fallbackAssign(origAssign: PtAugmentedAssign): IRCodeChunks {
-        if (codeGen.options.slowCodegenWarnings)
-            codeGen.errors.warn("indirect code for in-place assignment", origAssign.position)
         val value: PtExpression
         if(origAssign.operator in PrefixOperators) {
             value = PtPrefix(origAssign.operator, origAssign.value.type, origAssign.value.position)
             value.add(origAssign.value)
         } else {
-            require(origAssign.operator.endsWith('='))
-            value = PtBinaryExpression(origAssign.operator.dropLast(1), origAssign.value.type, origAssign.value.position)
+            val operator = when(origAssign.operator) {
+                in ComparisonOperators -> origAssign.operator
+                else -> {
+                    require(origAssign.operator.endsWith('='))
+                    origAssign.operator.dropLast(1)
+                }
+            }
+            value = PtBinaryExpression(operator, origAssign.value.type, origAssign.value.position)
             val left: PtExpression = origAssign.target.children.single() as PtExpression
             value.add(left)
             value.add(origAssign.value)
@@ -115,28 +84,161 @@ internal class AssignmentGen(private val codeGen: IRCodeGen, private val express
         return translateRegularAssign(normalAssign)
     }
 
-    private fun inplacePrefix(operator: String, vmDt: IRDataType, address: Int?, symbol: String?): IRCodeChunks {
-        val code= IRCodeChunk(null, null)
+    private fun inplacePrefix(operator: String, symbol: String?, array: PtArrayIndexer?, constAddress: Int?, memory: PtMemoryByte?, vmDt: IRDataType): Result<IRCodeChunks, NotImplementedError> {
+        if(operator=="+")
+            return Ok(emptyList())
+
+        if(array!=null)
+            return Ok(inplacePrefixArray(operator, array))
+
+        val result = mutableListOf<IRCodeChunkBase>()
+        if(constAddress==null && memory!=null) {
+            val register = codeGen.registers.nextFree()
+            val tr = expressionEval.translateExpression(memory.address)
+            addToResult(result, tr, tr.resultReg, -1)
+            when(operator) {
+                "-" -> {
+                    result += IRCodeChunk(null, null).also {
+                        it += IRInstruction(Opcode.LOADI, vmDt, reg1=register, reg2=tr.resultReg)
+                        it += IRInstruction(Opcode.NEG, vmDt, reg1=register)
+                        it += IRInstruction(Opcode.STOREI, vmDt, reg1=register, reg2=tr.resultReg)
+                    }
+                }
+                "~" -> {
+                    result += IRCodeChunk(null, null).also {
+                        it += IRInstruction(Opcode.LOADI, vmDt, reg1=register, reg2=tr.resultReg)
+                        it += IRInstruction(Opcode.INV, vmDt, reg1=register)
+                        it += IRInstruction(Opcode.STOREI, vmDt, reg1=register, reg2=tr.resultReg)
+                    }
+                }
+            }
+        } else {
+            when (operator) {
+                "-" -> addInstr(result, IRInstruction(Opcode.NEGM, vmDt, address = constAddress, labelSymbol = symbol), null)
+                "~" -> addInstr(result, IRInstruction(Opcode.INVM, vmDt, address = constAddress, labelSymbol = symbol), null)
+                // TODO: in boolean branch, how is 'not' handled here?
+                else -> throw AssemblyError("weird prefix operator")
+            }
+        }
+        return Ok(result)
+    }
+
+    private fun inplacePrefixArray(operator: String, array: PtArrayIndexer): IRCodeChunks {
+        val eltSize = codeGen.program.memsizer.memorySize(array.type)
+        val result = mutableListOf<IRCodeChunkBase>()
+        val vmDt = irType(array.type)
+        val constIndex = array.index.asConstInteger()
+
+        fun loadIndex(): Int {
+            val tr = expressionEval.translateExpression(array.index)
+            addToResult(result, tr, tr.resultReg, -1)
+            if(!array.splitWords && eltSize>1)
+                result += codeGen.multiplyByConst(IRDataType.BYTE, tr.resultReg, eltSize)
+            return tr.resultReg
+        }
+
+        if(array.splitWords) {
+            // handle split LSB/MSB arrays
+            when(operator) {
+                "+" -> { }
+                "-" -> {
+                    val skipCarryLabel = codeGen.createLabelName()
+                    if(constIndex!=null) {
+                        addInstr(result, IRInstruction(Opcode.NEGM, IRDataType.BYTE, labelSymbol = array.variable.name+"_lsb", symbolOffset = constIndex), null)
+                        addInstr(result, IRInstruction(Opcode.BSTEQ, labelSymbol = skipCarryLabel), null)
+                        addInstr(result, IRInstruction(Opcode.INCM, IRDataType.BYTE, labelSymbol = array.variable.name+"_msb", symbolOffset = constIndex), null)
+                        addInstr(result, IRInstruction(Opcode.NEGM, IRDataType.BYTE, labelSymbol = array.variable.name+"_msb", symbolOffset = constIndex), skipCarryLabel)
+                    } else {
+                        val indexReg = loadIndex()
+                        val registerLsb = codeGen.registers.nextFree()
+                        val registerMsb = codeGen.registers.nextFree()
+                        result += IRCodeChunk(null, null).also {
+                            it += IRInstruction(Opcode.LOADX, IRDataType.BYTE, reg1 = registerLsb, reg2 = indexReg, labelSymbol = array.variable.name+"_lsb")
+                            it += IRInstruction(Opcode.NEG, IRDataType.BYTE, reg1 = registerLsb)
+                            it += IRInstruction(Opcode.STOREX, IRDataType.BYTE, reg1 = registerLsb, reg2 = indexReg, labelSymbol = array.variable.name+"_lsb")
+                            it += IRInstruction(Opcode.LOADX, IRDataType.BYTE, reg1 = registerMsb, reg2 = indexReg, labelSymbol = array.variable.name+"_msb")
+                            it += IRInstruction(Opcode.NEG, IRDataType.BYTE, reg1 = registerMsb)
+                            it += IRInstruction(Opcode.CMPI, IRDataType.BYTE, reg1 = registerLsb, immediate = 0)
+                            it += IRInstruction(Opcode.BSTEQ, labelSymbol = skipCarryLabel)
+                            it += IRInstruction(Opcode.DEC, IRDataType.BYTE, reg1 = registerMsb)
+                        }
+                        result += IRCodeChunk(skipCarryLabel, null).also {
+                            it += IRInstruction(Opcode.STOREX, IRDataType.BYTE, reg1 = registerMsb, reg2 = indexReg, labelSymbol = array.variable.name+"_msb")
+                        }
+                    }
+                }
+                "~" -> {
+                    if(constIndex!=null) {
+                        addInstr(result, IRInstruction(Opcode.INVM, IRDataType.BYTE, labelSymbol = array.variable.name+"_lsb", symbolOffset = constIndex), null)
+                        addInstr(result, IRInstruction(Opcode.INVM, IRDataType.BYTE, labelSymbol = array.variable.name+"_msb", symbolOffset = constIndex), null)
+                    } else {
+                        val indexReg = loadIndex()
+                        val register = codeGen.registers.nextFree()
+                        result += IRCodeChunk(null, null).also {
+                            it += IRInstruction(Opcode.LOADX, IRDataType.BYTE, reg1 = register, reg2 = indexReg, labelSymbol = array.variable.name+"_lsb")
+                            it += IRInstruction(Opcode.INV, IRDataType.BYTE, reg1 = register)
+                            it += IRInstruction(Opcode.STOREX, IRDataType.BYTE, reg1 = register, reg2 = indexReg, labelSymbol = array.variable.name+"_lsb")
+                            it += IRInstruction(Opcode.LOADX, IRDataType.BYTE, reg1 = register, reg2 = indexReg, labelSymbol = array.variable.name+"_msb")
+                            it += IRInstruction(Opcode.INV, IRDataType.BYTE, reg1 = register)
+                            it += IRInstruction(Opcode.STOREX, IRDataType.BYTE, reg1 = register, reg2 = indexReg, labelSymbol = array.variable.name+"_msb")
+                        }
+                    }
+                }
+                else -> throw AssemblyError("weird prefix operator")
+            }
+            return result
+        }
+
+        // normal array.
+
         when(operator) {
             "+" -> { }
             "-" -> {
-                code += if(address!=null)
-                    IRInstruction(Opcode.NEGM, vmDt, address = address)
-                else
-                    IRInstruction(Opcode.NEGM, vmDt, labelSymbol = symbol)
+                if(constIndex!=null) {
+                    addInstr(result, IRInstruction(Opcode.NEGM, vmDt, labelSymbol = array.variable.name, symbolOffset = constIndex*eltSize), null)
+                } else {
+                    val indexReg = loadIndex()
+                    val register = codeGen.registers.nextFree()
+                    result += IRCodeChunk(null, null).also {
+                        it += IRInstruction(Opcode.LOADX, vmDt, reg1 = register, reg2 = indexReg, labelSymbol = array.variable.name)
+                        it += IRInstruction(Opcode.NEG, vmDt, reg1 = register)
+                        it += IRInstruction(Opcode.STOREX, vmDt, reg1 = register, reg2 = indexReg, labelSymbol = array.variable.name)
+                    }
+                }
             }
             "~" -> {
-                val regMask = codeGen.registers.nextFree()
-                val mask = if(vmDt==IRDataType.BYTE) 0x00ff else 0xffff
-                code += IRInstruction(Opcode.LOAD, vmDt, reg1=regMask, immediate = mask)
-                code += if(address!=null)
-                    IRInstruction(Opcode.XORM, vmDt, reg1=regMask, address = address)
-                else
-                    IRInstruction(Opcode.XORM, vmDt, reg1=regMask, labelSymbol = symbol)
+                if(constIndex!=null) {
+                    addInstr(result, IRInstruction(Opcode.INVM, vmDt, labelSymbol = array.variable.name, symbolOffset = constIndex*eltSize), null)
+                } else {
+                    val indexReg = loadIndex()
+                    val register = codeGen.registers.nextFree()
+                    result += IRCodeChunk(null, null).also {
+                        it += IRInstruction(Opcode.LOADX, vmDt, reg1 = register, reg2 = indexReg, labelSymbol = array.variable.name)
+                        it += IRInstruction(Opcode.INV, vmDt, reg1 = register)
+                        it += IRInstruction(Opcode.STOREX, vmDt, reg1 = register, reg2 = indexReg, labelSymbol = array.variable.name)
+                    }
+                }
+            }
+            "not" -> {
+                // TODO: in boolean branch, is 'not' handled ok like this?
+                val register = codeGen.registers.nextFree()
+                if(constIndex!=null) {
+                    result += IRCodeChunk(null, null).also {
+                        it += IRInstruction(Opcode.LOAD, vmDt, reg1=register, immediate = 1)
+                        it += IRInstruction(Opcode.XORM, vmDt, reg1=register, labelSymbol = array.variable.name, symbolOffset = constIndex*eltSize)
+                    }
+                } else {
+                    val indexReg = loadIndex()
+                    result += IRCodeChunk(null, null).also {
+                        it += IRInstruction(Opcode.LOADX, vmDt, reg1 = register, reg2 = indexReg, labelSymbol = array.variable.name)
+                        it += IRInstruction(Opcode.XOR, vmDt, reg1 = register, immediate = 1)
+                        it += IRInstruction(Opcode.STOREX, vmDt, reg1 = register, reg2 = indexReg, labelSymbol = array.variable.name)
+                    }
+                }
             }
             else -> throw AssemblyError("weird prefix operator")
         }
-        return listOf(code)
+        return result
     }
 
     private fun translateRegularAssign(assignment: PtAssignment): IRCodeChunks {
@@ -200,37 +302,17 @@ internal class AssignmentGen(private val codeGen: IRCodeGen, private val express
             val variable = targetArray.variable.name
             val itemsize = codeGen.program.memsizer.memorySize(targetArray.type)
 
-            if(targetArray.variable.type==DataType.UWORD) {
-                // indexing a pointer var instead of a real array or string
-                if(itemsize!=1)
-                    throw AssemblyError("non-array var indexing requires bytes dt")
-                if(targetArray.index.type!=DataType.UBYTE)
-                    throw AssemblyError("non-array var indexing requires bytes index")
-                val tr = expressionEval.translateExpression(targetArray.index)
-                val idxReg = tr.resultReg
-                addToResult(result, tr, tr.resultReg, -1)
-                val code = IRCodeChunk(null, null)
-                if(zero) {
-                    // there's no STOREZIX instruction
-                    valueRegister = codeGen.registers.nextFree()
-                    code += IRInstruction(Opcode.LOAD, targetDt, reg1=valueRegister, immediate = 0)
-                }
-                code += IRInstruction(Opcode.STOREIX, targetDt, reg1=valueRegister, reg2=idxReg, labelSymbol = variable)
-                result += code
-                return result
-            }
-
             val fixedIndex = constIntValue(targetArray.index)
             val arrayLength = codeGen.symbolTable.getLength(targetArray.variable.name)
             if(zero) {
                 if(fixedIndex!=null) {
                     val chunk = IRCodeChunk(null, null).also {
                         if(targetArray.splitWords) {
-                            it += IRInstruction(Opcode.STOREZM, IRDataType.BYTE, immediate = arrayLength, labelSymbol = "${variable}_lsb+$fixedIndex")
-                            it += IRInstruction(Opcode.STOREZM, IRDataType.BYTE, immediate = arrayLength, labelSymbol = "${variable}_msb+$fixedIndex")
+                            it += IRInstruction(Opcode.STOREZM, IRDataType.BYTE, immediate = arrayLength, labelSymbol = "${variable}_lsb", symbolOffset = fixedIndex)
+                            it += IRInstruction(Opcode.STOREZM, IRDataType.BYTE, immediate = arrayLength, labelSymbol = "${variable}_msb", symbolOffset = fixedIndex)
                         }
                         else
-                            it += IRInstruction(Opcode.STOREZM, targetDt, labelSymbol = "$variable+${fixedIndex*itemsize}")
+                            it += IRInstruction(Opcode.STOREZM, targetDt, labelSymbol = variable, symbolOffset = fixedIndex*itemsize)
                     }
                     result += chunk
                 } else {
@@ -250,7 +332,7 @@ internal class AssignmentGen(private val codeGen: IRCodeGen, private val express
                     if(fixedIndex!=null) {
                         val offset = fixedIndex*itemsize
                         val chunk = IRCodeChunk(null, null).also {
-                            it += IRInstruction(Opcode.STOREM, targetDt, fpReg1 = valueFpRegister, labelSymbol = "$variable+$offset")
+                            it += IRInstruction(Opcode.STOREM, targetDt, fpReg1 = valueFpRegister, labelSymbol = variable, symbolOffset = offset)
                         }
                         result += chunk
                     } else {
@@ -265,12 +347,12 @@ internal class AssignmentGen(private val codeGen: IRCodeGen, private val express
                         val chunk = IRCodeChunk(null, null).also {
                             if(targetArray.splitWords) {
                                 val msbReg = codeGen.registers.nextFree()
-                                it += IRInstruction(Opcode.STOREM, IRDataType.BYTE, reg1 = valueRegister, immediate = arrayLength, labelSymbol = "${variable}_lsb+$fixedIndex")
+                                it += IRInstruction(Opcode.STOREM, IRDataType.BYTE, reg1 = valueRegister, immediate = arrayLength, labelSymbol = "${variable}_lsb", symbolOffset = fixedIndex)
                                 it += IRInstruction(Opcode.MSIG, IRDataType.BYTE, reg1 = msbReg, reg2 = valueRegister)
-                                it += IRInstruction(Opcode.STOREM, IRDataType.BYTE, reg1 = msbReg, immediate = arrayLength, labelSymbol = "${variable}_msb+$fixedIndex")
+                                it += IRInstruction(Opcode.STOREM, IRDataType.BYTE, reg1 = msbReg, immediate = arrayLength, labelSymbol = "${variable}_msb", symbolOffset = fixedIndex)
                             }
                             else
-                                it += IRInstruction(Opcode.STOREM, targetDt, reg1 = valueRegister, labelSymbol = "$variable+${fixedIndex*itemsize}")
+                                it += IRInstruction(Opcode.STOREM, targetDt, reg1 = valueRegister, labelSymbol = variable, symbolOffset = fixedIndex*itemsize)
                         }
                         result += chunk
                     } else {
@@ -301,18 +383,47 @@ internal class AssignmentGen(private val codeGen: IRCodeGen, private val express
                     val tr = expressionEval.translateExpression(targetMemory.address)
                     val addressReg = tr.resultReg
                     addToResult(result, tr, tr.resultReg, -1)
-                    result += IRCodeChunk(null, null).also { it += IRInstruction(Opcode.STOREZI, targetDt, reg1=addressReg) }
+                    result += IRCodeChunk(null, null).also {
+                        it += IRInstruction(Opcode.STOREZI, targetDt, reg1=addressReg)
+                    }
                 }
             } else {
-                if(targetMemory.address is PtNumber) {
-                    val chunk = IRCodeChunk(null, null).also { it += IRInstruction(Opcode.STOREM, targetDt, reg1=valueRegister, address=(targetMemory.address as PtNumber).number.toInt()) }
-                    result += chunk
-                } else {
-                    val tr = expressionEval.translateExpression(targetMemory.address)
-                    val addressReg = tr.resultReg
-                    addToResult(result, tr, tr.resultReg, -1)
-                    result += IRCodeChunk(null, null).also { it += IRInstruction(Opcode.STOREI, targetDt, reg1=valueRegister, reg2=addressReg) }
+                val constAddress = targetMemory.address as? PtNumber
+                if(constAddress!=null) {
+                    addInstr(result, IRInstruction(Opcode.STOREM, targetDt, reg1=valueRegister, address=constAddress.number.toInt()), null)
+                    return result
                 }
+                val ptrWithOffset = targetMemory.address as? PtBinaryExpression
+                if(ptrWithOffset!=null && ptrWithOffset.operator=="+" && ptrWithOffset.left is PtIdentifier) {
+                    if((ptrWithOffset.right as? PtNumber)?.number?.toInt() in 0..255) {
+                        // STOREIX only works with byte index.
+                        val ptrName = (ptrWithOffset.left as PtIdentifier).name
+                        val offsetReg = codeGen.registers.nextFree()
+                        result += IRCodeChunk(null, null).also {
+                            it += IRInstruction(Opcode.LOAD, IRDataType.BYTE, reg1=offsetReg, immediate = ptrWithOffset.right.asConstInteger())
+                            it += IRInstruction(Opcode.STOREIX, IRDataType.BYTE, reg1=valueRegister, reg2=offsetReg, labelSymbol = ptrName)
+                        }
+                        return result
+                    }
+                }
+                val offsetTypecast = ptrWithOffset?.right as? PtTypeCast
+                if(ptrWithOffset!=null && ptrWithOffset.operator=="+" && ptrWithOffset.left is PtIdentifier
+                    && (ptrWithOffset.right.type in ByteDatatypes || offsetTypecast?.value?.type in ByteDatatypes)) {
+                    // STOREIX only works with byte index.
+                    val tr = if(offsetTypecast?.value?.type in ByteDatatypes)
+                        expressionEval.translateExpression(offsetTypecast!!.value)
+                    else
+                        expressionEval.translateExpression(ptrWithOffset.right)
+                    addToResult(result, tr, tr.resultReg, -1)
+                    val ptrName = (ptrWithOffset.left as PtIdentifier).name
+                    addInstr(result, IRInstruction(Opcode.STOREIX, IRDataType.BYTE, reg1=valueRegister, reg2=tr.resultReg, labelSymbol = ptrName), null)
+                    return result
+                }
+                val tr = expressionEval.translateExpression(targetMemory.address)
+                val addressReg = tr.resultReg
+                addToResult(result, tr, tr.resultReg, -1)
+                addInstr(result, IRInstruction(Opcode.STOREI, targetDt, reg1=valueRegister, reg2=addressReg), null)
+                return result
             }
 
             return result

codeGenIntermediate/src/prog8/codegen/intermediate/BuiltinFuncGen.kt

@@ -20,40 +20,68 @@ internal class BuiltinFuncGen(private val codeGen: IRCodeGen, private val exprGe
             "sqrt__ubyte", "sqrt__uword", "sqrt__float" -> funcSqrt(call)
             "divmod__ubyte" -> funcDivmod(call, IRDataType.BYTE)
             "divmod__uword" -> funcDivmod(call, IRDataType.WORD)
-            "pop" -> funcPop(call)
-            "popw" -> funcPopw(call)
-            "push" -> funcPush(call)
-            "pushw" -> funcPushw(call)
-            "rsave",
-            "rsavex",
-            "rrestore",
-            "rrestorex" -> ExpressionCodeResult.EMPTY  // vm doesn't have registers to save/restore
+            "rsave", "rrestore" -> ExpressionCodeResult.EMPTY  // vm doesn't have registers to save/restore
             "callfar" -> funcCallfar(call)
+            "call" -> funcCall(call)
             "msb" -> funcMsb(call)
             "lsb" -> funcLsb(call)
             "memory" -> funcMemory(call)
-            "peek" -> funcPeek(call)
-            "peekw" -> funcPeekW(call)
-            "poke" -> funcPoke(call)
-            "pokew" -> funcPokeW(call)
-            "pokemon" -> ExpressionCodeResult.EMPTY     // easter egg function
+            "peek" -> funcPeek(call, IRDataType.BYTE)
+            "peekw" -> funcPeek(call, IRDataType.WORD)
+            "peekf" -> funcPeek(call, IRDataType.FLOAT)
+            "poke" -> funcPoke(call, IRDataType.BYTE)
+            "pokew" -> funcPoke(call, IRDataType.WORD)
+            "pokef" -> funcPoke(call, IRDataType.FLOAT)
+            "pokemon" -> funcPokemon(call)
             "mkword" -> funcMkword(call)
             "clamp__byte", "clamp__ubyte", "clamp__word", "clamp__uword" -> funcClamp(call)
             "min__byte", "min__ubyte", "min__word", "min__uword" -> funcMin(call)
             "max__byte", "max__ubyte", "max__word", "max__uword" -> funcMax(call)
             "sort" -> funcSort(call)
             "reverse" -> funcReverse(call)
-            "rol" -> funcRolRor(Opcode.ROXL, call)
-            "ror" -> funcRolRor(Opcode.ROXR, call)
-            "rol2" -> funcRolRor(Opcode.ROL, call)
-            "ror2" -> funcRolRor(Opcode.ROR, call)
+            "setlsb" -> funcSetLsbMsb(call, false)
+            "setmsb" -> funcSetLsbMsb(call, true)
+            "rol" -> funcRolRor(call)
+            "ror" -> funcRolRor(call)
+            "rol2" -> funcRolRor(call)
+            "ror2" -> funcRolRor(call)
             "prog8_lib_stringcompare" -> funcStringCompare(call)
+            "prog8_lib_square_byte" -> funcSquare(call, IRDataType.BYTE)
+            "prog8_lib_square_word" -> funcSquare(call, IRDataType.WORD)
             else -> throw AssemblyError("missing builtinfunc for ${call.name}")
         }
     }
 
+    private fun funcSquare(call: PtBuiltinFunctionCall, resultType: IRDataType): ExpressionCodeResult {
+        val result = mutableListOf<IRCodeChunkBase>()
+        val valueTr = exprGen.translateExpression(call.args[0])
+        addToResult(result, valueTr, valueTr.resultReg, valueTr.resultFpReg)
+        return if(resultType==IRDataType.FLOAT) {
+            val resultFpReg = codeGen.registers.nextFreeFloat()
+            addInstr(result, IRInstruction(Opcode.SQUARE, resultType, fpReg1 = resultFpReg, fpReg2 = valueTr.resultFpReg), null)
+            ExpressionCodeResult(result, resultType, -1, resultFpReg)
+        }
+        else {
+            val resultReg = codeGen.registers.nextFree()
+            addInstr(result, IRInstruction(Opcode.SQUARE, resultType, reg1 = resultReg, reg2 = valueTr.resultReg), null)
+            ExpressionCodeResult(result, resultType, resultReg, -1)
+        }
+    }
+
+    private fun funcCall(call: PtBuiltinFunctionCall): ExpressionCodeResult {
+        val result = mutableListOf<IRCodeChunkBase>()
+        val addressTr = exprGen.translateExpression(call.args[0])
+        addToResult(result, addressTr, addressTr.resultReg, -1)
+        addInstr(result, IRInstruction(Opcode.CALLI, reg1 = addressTr.resultReg), null)
+        if(call.void)
+            return ExpressionCodeResult(result, IRDataType.BYTE, -1, -1)
+        else
+            return ExpressionCodeResult(result, IRDataType.WORD, codeGen.registers.nextFree(), -1)      // TODO actually the result is returned in CPU registers AY...
+    }
+
     private fun funcCallfar(call: PtBuiltinFunctionCall): ExpressionCodeResult {
         val result = mutableListOf<IRCodeChunkBase>()
+        addInstr(result, IRInstruction(Opcode.PREPARECALL, immediate = 3), null)
         val bankTr = exprGen.translateExpression(call.args[0])
         val addressTr = exprGen.translateExpression(call.args[1])
         val argumentwordTr = exprGen.translateExpression(call.args[2])
@@ -95,6 +123,7 @@ internal class BuiltinFuncGen(private val codeGen: IRCodeGen, private val exprGe
 
     private fun funcStringCompare(call: PtBuiltinFunctionCall): ExpressionCodeResult {
         val result = mutableListOf<IRCodeChunkBase>()
+        addInstr(result, IRInstruction(Opcode.PREPARECALL, immediate = 2), null)
         val left  = exprGen.translateExpression(call.args[0])
         val right = exprGen.translateExpression(call.args[1])
         addToResult(result, left, left.resultReg, -1)
@@ -119,6 +148,31 @@ internal class BuiltinFuncGen(private val codeGen: IRCodeGen, private val exprGe
     private fun funcAny(call: PtBuiltinFunctionCall): ExpressionCodeResult {
         val arrayName = call.args[0] as PtIdentifier
         val arrayLength = codeGen.symbolTable.getLength(arrayName.name)
+        val result = mutableListOf<IRCodeChunkBase>()
+        val lengthReg = codeGen.registers.nextFree()
+
+        if(arrayName.type in SplitWordArrayTypes) {
+            // any(lsb-array) or any(msb-array)
+            addInstr(result, IRInstruction(Opcode.PREPARECALL, immediate = 2), null)
+            val trLsb = exprGen.translateExpression(PtIdentifier(arrayName.name+"_lsb", DataType.ARRAY_UB, call.position))
+            addToResult(result, trLsb, trLsb.resultReg, -1)
+            addInstr(result, IRInstruction(Opcode.LOAD, IRDataType.BYTE, reg1 = lengthReg, immediate = arrayLength), null)
+            result += codeGen.makeSyscall(IMSyscall.ANY_BYTE, listOf(IRDataType.WORD to trLsb.resultReg, IRDataType.BYTE to lengthReg), IRDataType.BYTE to trLsb.resultReg)
+            val shortcircuitLabel = codeGen.createLabelName()
+            result += IRCodeChunk(null, null).also {
+                it += IRInstruction(Opcode.CMPI, IRDataType.BYTE, reg1 = trLsb.resultReg, immediate = 0)
+                it += IRInstruction(Opcode.BSTNE, labelSymbol = shortcircuitLabel)
+                it += IRInstruction(Opcode.PREPARECALL, immediate = 2)
+            }
+            val trMsb = exprGen.translateExpression(PtIdentifier(arrayName.name+"_msb", DataType.ARRAY_UB, call.position))
+            addToResult(result, trMsb, trMsb.resultReg, -1)
+            addInstr(result, IRInstruction(Opcode.LOAD, IRDataType.BYTE, reg1 = lengthReg, immediate = arrayLength), null)
+            result += codeGen.makeSyscall(IMSyscall.ANY_BYTE, listOf(IRDataType.WORD to trMsb.resultReg, IRDataType.BYTE to lengthReg), IRDataType.BYTE to trMsb.resultReg)
+            addInstr(result, IRInstruction(Opcode.ORR, IRDataType.BYTE, reg1=trLsb.resultReg, reg2=trMsb.resultReg), null)
+            result += IRCodeChunk(shortcircuitLabel, null)
+            return ExpressionCodeResult(result, IRDataType.BYTE, trLsb.resultReg, -1)
+        }
+
         val syscall =
             when (arrayName.type) {
                 DataType.ARRAY_UB,
@@ -128,10 +182,9 @@ internal class BuiltinFuncGen(private val codeGen: IRCodeGen, private val exprGe
                 DataType.ARRAY_F -> IMSyscall.ANY_FLOAT
                 else -> throw IllegalArgumentException("weird type")
             }
-        val result = mutableListOf<IRCodeChunkBase>()
-        val tr = exprGen.translateExpression(call.args[0])
+        addInstr(result, IRInstruction(Opcode.PREPARECALL, immediate = 2), null)
+        val tr = exprGen.translateExpression(arrayName)
         addToResult(result, tr, tr.resultReg, -1)
-        val lengthReg = codeGen.registers.nextFree()
         addInstr(result, IRInstruction(Opcode.LOAD, IRDataType.BYTE, reg1 = lengthReg, immediate = arrayLength), null)
         result += codeGen.makeSyscall(syscall, listOf(IRDataType.WORD to tr.resultReg, IRDataType.BYTE to lengthReg), IRDataType.BYTE to tr.resultReg)
         return ExpressionCodeResult(result, IRDataType.BYTE, tr.resultReg, -1)
@@ -140,6 +193,12 @@ internal class BuiltinFuncGen(private val codeGen: IRCodeGen, private val exprGe
     private fun funcAll(call: PtBuiltinFunctionCall): ExpressionCodeResult {
         val arrayName = call.args[0] as PtIdentifier
         val arrayLength = codeGen.symbolTable.getLength(arrayName.name)
+
+        if(arrayName.type in SplitWordArrayTypes) {
+            // this is a bit complicated to calculate.... have to check all recombined (lsb,msb) words for $0000
+            TODO("all(split words $arrayName)")
+        }
+
         val syscall =
             when(arrayName.type) {
                 DataType.ARRAY_UB,
@@ -150,7 +209,8 @@ internal class BuiltinFuncGen(private val codeGen: IRCodeGen, private val exprGe
                 else -> throw IllegalArgumentException("weird type")
             }
         val result = mutableListOf<IRCodeChunkBase>()
-        val tr = exprGen.translateExpression(call.args[0])
+        addInstr(result, IRInstruction(Opcode.PREPARECALL, immediate = 2), null)
+        val tr = exprGen.translateExpression(arrayName)
         addToResult(result, tr, tr.resultReg, -1)
         val lengthReg = codeGen.registers.nextFree()
         addInstr(result, IRInstruction(Opcode.LOAD, IRDataType.BYTE, reg1 = lengthReg, immediate = arrayLength), null)
@@ -200,14 +260,21 @@ internal class BuiltinFuncGen(private val codeGen: IRCodeGen, private val exprGe
 
     private fun funcSgn(call: PtBuiltinFunctionCall): ExpressionCodeResult {
         val result = mutableListOf<IRCodeChunkBase>()
-        val vmDt = irType(call.type)
         val tr = exprGen.translateExpression(call.args.single())
-        addToResult(result, tr, tr.resultReg, -1)
         val resultReg = codeGen.registers.nextFree()
-        result += IRCodeChunk(null, null).also {
-            it += IRInstruction(Opcode.SGN, vmDt, reg1 = resultReg, reg2 = tr.resultReg)
+
+        if(tr.dt==IRDataType.FLOAT) {
+            addToResult(result, tr, -1, tr.resultFpReg)
+            result += IRCodeChunk(null, null).also {
+                it += IRInstruction(Opcode.SGN, tr.dt, reg1 = resultReg, fpReg1 = tr.resultFpReg)
+            }
+        } else {
+            addToResult(result, tr, tr.resultReg, -1)
+            result += IRCodeChunk(null, null).also {
+                it += IRInstruction(Opcode.SGN, tr.dt, reg1 = resultReg, reg2 = tr.resultReg)
+            }
         }
-        return ExpressionCodeResult(result, vmDt, resultReg, -1)
+        return ExpressionCodeResult(result, IRDataType.BYTE, resultReg, -1)
     }
 
     private fun funcSqrt(call: PtBuiltinFunctionCall): ExpressionCodeResult {
@@ -239,63 +306,40 @@ internal class BuiltinFuncGen(private val codeGen: IRCodeGen, private val exprGe
                 }
                 return ExpressionCodeResult(result, IRDataType.FLOAT, -1, resultFpReg)
             }
-            else -> throw AssemblyError("invalid dt for sqrt")
+            else -> throw AssemblyError("invalid dt")
         }
     }
 
-    private fun funcPop(call: PtBuiltinFunctionCall): ExpressionCodeResult {
-        val code = IRCodeChunk(null, null)
-        val reg = codeGen.registers.nextFree()
-        code += IRInstruction(Opcode.POP, IRDataType.BYTE, reg1=reg)
-        val result = mutableListOf<IRCodeChunkBase>(code)
-        result += assignRegisterTo(call.args.single(), reg)
-        return ExpressionCodeResult(result, IRDataType.BYTE, reg, -1)
-    }
-
-    private fun funcPopw(call: PtBuiltinFunctionCall): ExpressionCodeResult {
-        val code = IRCodeChunk(null, null)
-        val reg = codeGen.registers.nextFree()
-        code += IRInstruction(Opcode.POP, IRDataType.WORD, reg1=reg)
-        val result = mutableListOf<IRCodeChunkBase>(code)
-        result += assignRegisterTo(call.args.single(), reg)
-        return ExpressionCodeResult(result, IRDataType.WORD, reg, -1)
-    }
-
-    private fun funcPush(call: PtBuiltinFunctionCall): ExpressionCodeResult {
-        val result = mutableListOf<IRCodeChunkBase>()
-        val tr = exprGen.translateExpression(call.args.single())
-        addToResult(result, tr, tr.resultReg, -1)
-        result += IRCodeChunk(null, null).also {
-            it += IRInstruction(Opcode.PUSH, IRDataType.BYTE, reg1=tr.resultReg)
-        }
-        return ExpressionCodeResult(result, IRDataType.BYTE, -1, -1)
-    }
-
-    private fun funcPushw(call: PtBuiltinFunctionCall): ExpressionCodeResult {
-        val result = mutableListOf<IRCodeChunkBase>()
-        val tr = exprGen.translateExpression(call.args.single())
-        addToResult(result, tr, tr.resultReg, -1)
-        result += IRCodeChunk(null, null).also {
-            it += IRInstruction(Opcode.PUSH, IRDataType.WORD, reg1 = tr.resultReg)
-        }
-        return ExpressionCodeResult(result, IRDataType.BYTE, -1, -1)
-    }
-
     private fun funcReverse(call: PtBuiltinFunctionCall): ExpressionCodeResult {
         val arrayName = call.args[0] as PtIdentifier
         val arrayLength = codeGen.symbolTable.getLength(arrayName.name)
+        val lengthReg = codeGen.registers.nextFree()
+        val result = mutableListOf<IRCodeChunkBase>()
+
+        if(arrayName.type in SplitWordArrayTypes) {
+            // reverse the lsb and msb arrays both, independently
+            addInstr(result, IRInstruction(Opcode.PREPARECALL, immediate = 2), null)
+            val trLsb = exprGen.translateExpression(PtIdentifier(arrayName.name+"_lsb", DataType.ARRAY_UB, call.position))
+            addToResult(result, trLsb, trLsb.resultReg, -1)
+            addInstr(result, IRInstruction(Opcode.LOAD, IRDataType.BYTE, reg1 = lengthReg, immediate = if(arrayName.type==DataType.STR) arrayLength!!-1 else arrayLength), null)
+            result += codeGen.makeSyscall(IMSyscall.REVERSE_BYTES, listOf(IRDataType.WORD to trLsb.resultReg, IRDataType.BYTE to lengthReg), null)
+            val trMsb = exprGen.translateExpression(PtIdentifier(arrayName.name+"_msb", DataType.ARRAY_UB, call.position))
+            addToResult(result, trMsb, trMsb.resultReg, -1)
+            addInstr(result, IRInstruction(Opcode.LOAD, IRDataType.BYTE, reg1 = lengthReg, immediate = if(arrayName.type==DataType.STR) arrayLength!!-1 else arrayLength), null)
+            result += codeGen.makeSyscall(IMSyscall.REVERSE_BYTES, listOf(IRDataType.WORD to trMsb.resultReg, IRDataType.BYTE to lengthReg), null)
+            return ExpressionCodeResult(result, IRDataType.BYTE, -1, -1)
+        }
+
         val syscall =
             when(arrayName.type) {
                 DataType.ARRAY_UB, DataType.ARRAY_B, DataType.STR -> IMSyscall.REVERSE_BYTES
                 DataType.ARRAY_UW, DataType.ARRAY_W -> IMSyscall.REVERSE_WORDS
                 DataType.ARRAY_F -> IMSyscall.REVERSE_FLOATS
-                in SplitWordArrayTypes -> TODO("split word reverse")
                 else -> throw IllegalArgumentException("weird type to reverse")
             }
-        val result = mutableListOf<IRCodeChunkBase>()
-        val tr = exprGen.translateExpression(call.args[0])
+        addInstr(result, IRInstruction(Opcode.PREPARECALL, immediate = 2), null)
+        val tr = exprGen.translateExpression(arrayName)
         addToResult(result, tr, tr.resultReg, -1)
-        val lengthReg = codeGen.registers.nextFree()
         addInstr(result, IRInstruction(Opcode.LOAD, IRDataType.BYTE, reg1 = lengthReg, immediate = if(arrayName.type==DataType.STR) arrayLength!!-1 else arrayLength), null)
         result += codeGen.makeSyscall(syscall, listOf(IRDataType.WORD to tr.resultReg, IRDataType.BYTE to lengthReg), null)
         return ExpressionCodeResult(result, IRDataType.BYTE, -1, -1)
@@ -316,7 +360,8 @@ internal class BuiltinFuncGen(private val codeGen: IRCodeGen, private val exprGe
                 else -> throw IllegalArgumentException("weird type to sort")
             }
         val result = mutableListOf<IRCodeChunkBase>()
-        val tr = exprGen.translateExpression(call.args[0])
+        addInstr(result, IRInstruction(Opcode.PREPARECALL, immediate = 2), null)
+        val tr = exprGen.translateExpression(arrayName)
         addToResult(result, tr, tr.resultReg, -1)
         val lengthReg = codeGen.registers.nextFree()
         addInstr(result, IRInstruction(Opcode.LOAD, IRDataType.BYTE, reg1 = lengthReg, immediate = if(arrayName.type==DataType.STR) arrayLength!!-1 else arrayLength), null)
@@ -326,19 +371,25 @@ internal class BuiltinFuncGen(private val codeGen: IRCodeGen, private val exprGe
 
     private fun funcMkword(call: PtBuiltinFunctionCall): ExpressionCodeResult {
         val result = mutableListOf<IRCodeChunkBase>()
-        val msbTr = exprGen.translateExpression(call.args[0])
-        addToResult(result, msbTr, msbTr.resultReg, -1)
-        val lsbTr = exprGen.translateExpression(call.args[1])
-        addToResult(result, lsbTr, lsbTr.resultReg, -1)
         val resultReg = codeGen.registers.nextFree()
-        result += IRCodeChunk(null, null).also {
-            it += IRInstruction(Opcode.CONCAT, IRDataType.BYTE, reg1=resultReg, reg2 = lsbTr.resultReg, reg3 = msbTr.resultReg)
+        if((call.args[0] as? PtNumber)?.number == 0.0) {
+            // msb is 0, use EXT
+            val lsbTr = exprGen.translateExpression(call.args[1])
+            addToResult(result, lsbTr, lsbTr.resultReg, -1)
+            addInstr(result, IRInstruction(Opcode.EXT, IRDataType.BYTE, reg1=resultReg, reg2 = lsbTr.resultReg), null)
+        } else {
+            val msbTr = exprGen.translateExpression(call.args[0])
+            addToResult(result, msbTr, msbTr.resultReg, -1)
+            val lsbTr = exprGen.translateExpression(call.args[1])
+            addToResult(result, lsbTr, lsbTr.resultReg, -1)
+            addInstr(result, IRInstruction(Opcode.CONCAT, IRDataType.BYTE, reg1=resultReg, reg2 = msbTr.resultReg, reg3 = lsbTr.resultReg), null)
         }
         return ExpressionCodeResult(result, IRDataType.WORD, resultReg, -1)
     }
 
     private fun funcClamp(call: PtBuiltinFunctionCall): ExpressionCodeResult {
         val result = mutableListOf<IRCodeChunkBase>()
+        addInstr(result, IRInstruction(Opcode.PREPARECALL, immediate = 3), null)
         val type = irType(call.type)
         val valueTr = exprGen.translateExpression(call.args[0])
         val minimumTr = exprGen.translateExpression(call.args[1])
@@ -411,118 +462,148 @@ internal class BuiltinFuncGen(private val codeGen: IRCodeGen, private val exprGe
         return ExpressionCodeResult(result, type, leftTr.resultReg, -1)
     }
 
-    private fun funcPokeW(call: PtBuiltinFunctionCall): ExpressionCodeResult {
+    private fun funcPoke(call: PtBuiltinFunctionCall, dt: IRDataType): ExpressionCodeResult {
         val result = mutableListOf<IRCodeChunkBase>()
         if(codeGen.isZero(call.args[1])) {
             if (call.args[0] is PtNumber) {
                 val address = (call.args[0] as PtNumber).number.toInt()
                 result += IRCodeChunk(null, null).also {
-                    it += IRInstruction(Opcode.STOREZM, IRDataType.WORD, address = address)
+                    it += IRInstruction(Opcode.STOREZM, dt, address = address)
                 }
             } else {
                 val tr = exprGen.translateExpression(call.args[0])
                 addToResult(result, tr, tr.resultReg, -1)
                 result += IRCodeChunk(null, null).also {
-                    it += IRInstruction(Opcode.STOREZI, IRDataType.WORD, reg1 = tr.resultReg)
+                    it += IRInstruction(Opcode.STOREZI, dt, reg1 = tr.resultReg)
                 }
             }
         } else {
             if (call.args[0] is PtNumber) {
                 val address = (call.args[0] as PtNumber).number.toInt()
                 val tr = exprGen.translateExpression(call.args[1])
-                addToResult(result, tr, tr.resultReg, -1)
-                result += IRCodeChunk(null, null).also {
-                    it += IRInstruction(Opcode.STOREM, IRDataType.WORD, reg1 = tr.resultReg, address = address)
+                if(dt==IRDataType.FLOAT) {
+                    addToResult(result, tr, -1, tr.resultFpReg)
+                    result += IRCodeChunk(null, null).also {
+                        it += IRInstruction(Opcode.STOREM, dt, fpReg1 = tr.resultFpReg, address = address)
+                    }
+                } else {
+                    addToResult(result, tr, tr.resultReg, -1)
+                    result += IRCodeChunk(null, null).also {
+                        it += IRInstruction(Opcode.STOREM, dt, reg1 = tr.resultReg, address = address)
+                    }
                 }
             } else {
                 val addressTr = exprGen.translateExpression(call.args[0])
                 addToResult(result, addressTr, addressTr.resultReg, -1)
                 val valueTr = exprGen.translateExpression(call.args[1])
-                addToResult(result, valueTr, valueTr.resultReg, -1)
-                result += IRCodeChunk(null, null).also {
-                    it += IRInstruction(Opcode.STOREI, IRDataType.WORD, reg1 = valueTr.resultReg, reg2 = addressTr.resultReg)
+                if(dt==IRDataType.FLOAT) {
+                    addToResult(result, valueTr, -1, valueTr.resultFpReg)
+                    result += IRCodeChunk(null, null).also {
+                        it += IRInstruction(Opcode.STOREI, IRDataType.FLOAT, reg1 = addressTr.resultReg, fpReg1 = valueTr.resultFpReg)
+                    }
+                } else {
+                    addToResult(result, valueTr, valueTr.resultReg, -1)
+                    result += IRCodeChunk(null, null).also {
+                        it += IRInstruction(Opcode.STOREI, dt, reg1 = valueTr.resultReg, reg2 = addressTr.resultReg)
+                    }
                 }
             }
         }
         return ExpressionCodeResult(result, IRDataType.BYTE, -1, -1)
     }
 
-    private fun funcPoke(call: PtBuiltinFunctionCall): ExpressionCodeResult {
+    private fun funcPeek(call: PtBuiltinFunctionCall, dt: IRDataType): ExpressionCodeResult {
         val result = mutableListOf<IRCodeChunkBase>()
-        if(codeGen.isZero(call.args[1])) {
-            if (call.args[0] is PtNumber) {
+        return if(dt==IRDataType.FLOAT) {
+            if(call.args[0] is PtNumber) {
+                val resultFpRegister = codeGen.registers.nextFreeFloat()
                 val address = (call.args[0] as PtNumber).number.toInt()
+                result += IRCodeChunk(null, null).also {
+                    it += IRInstruction(Opcode.LOADM, IRDataType.FLOAT, fpReg1 = resultFpRegister, address = address)
+                }
+                ExpressionCodeResult(result, IRDataType.FLOAT, -1, resultFpRegister)
+            } else {
+                val tr = exprGen.translateExpression(call.args.single())
+                addToResult(result, tr, tr.resultReg, -1)
+                val resultFpReg = codeGen.registers.nextFreeFloat()
+                result += IRCodeChunk(null, null).also {
+                    it += IRInstruction(Opcode.LOADI, IRDataType.FLOAT, reg1 = tr.resultReg, fpReg1 = resultFpReg)
+                }
+                ExpressionCodeResult(result, IRDataType.FLOAT, -1, resultFpReg)
+            }
+        } else {
+            if (call.args[0] is PtNumber) {
+                val resultRegister = codeGen.registers.nextFree()
+                val address = (call.args[0] as PtNumber).number.toInt()
+                result += IRCodeChunk(null, null).also {
+                    it += IRInstruction(Opcode.LOADM, dt, reg1 = resultRegister, address = address)
+                }
+                ExpressionCodeResult(result, dt, resultRegister, -1)
+            } else {
+                val tr = exprGen.translateExpression(call.args.single())
+                addToResult(result, tr, tr.resultReg, -1)
+                val resultReg = codeGen.registers.nextFree()
+                result += IRCodeChunk(null, null).also {
+                    it += IRInstruction(Opcode.LOADI, dt, reg1 = resultReg, reg2 = tr.resultReg)
+                }
+                ExpressionCodeResult(result, dt, resultReg, -1)
+            }
+        }
+    }
+
+    private fun funcPokemon(call: PtBuiltinFunctionCall): ExpressionCodeResult {
+        val result = mutableListOf<IRCodeChunkBase>()
+        val address = call.args[0]
+
+        fun pokeM(result: MutableList<IRCodeChunkBase>, address: Int, value: PtExpression) {
+            if(codeGen.isZero(value)) {
                 result += IRCodeChunk(null, null).also {
                     it += IRInstruction(Opcode.STOREZM, IRDataType.BYTE, address = address)
                 }
             } else {
-                val tr = exprGen.translateExpression(call.args[0])
-                addToResult(result, tr, tr.resultReg, -1)
-                result += IRCodeChunk(null, null).also {
-                    it += IRInstruction(Opcode.STOREZI, IRDataType.BYTE, reg1 = tr.resultReg)
-                }
-            }
-        } else {
-            if (call.args[0] is PtNumber) {
-                val address = (call.args[0] as PtNumber).number.toInt()
-                val tr = exprGen.translateExpression(call.args[1])
+                val tr = exprGen.translateExpression(value)
                 addToResult(result, tr, tr.resultReg, -1)
                 result += IRCodeChunk(null, null).also {
                     it += IRInstruction(Opcode.STOREM, IRDataType.BYTE, reg1 = tr.resultReg, address = address)
                 }
+            }
+        }
+
+        fun pokeI(result: MutableList<IRCodeChunkBase>, register: Int, value: PtExpression) {
+            if(codeGen.isZero(value)) {
+                result += IRCodeChunk(null, null).also {
+                    it += IRInstruction(Opcode.STOREZI, IRDataType.BYTE, reg1 = register)
+                }
             } else {
-                val addressTr = exprGen.translateExpression(call.args[0])
-                addToResult(result, addressTr, addressTr.resultReg, -1)
-                val valueTr = exprGen.translateExpression(call.args[1])
+                val valueTr = exprGen.translateExpression(value)
                 addToResult(result, valueTr, valueTr.resultReg, -1)
                 result += IRCodeChunk(null, null).also {
-                    it += IRInstruction(Opcode.STOREI, IRDataType.BYTE, reg1 = valueTr.resultReg, reg2 = addressTr.resultReg)
+                    it += IRInstruction(Opcode.STOREI, IRDataType.BYTE, reg1 = valueTr.resultReg, reg2 = register)
                 }
             }
         }
-        return ExpressionCodeResult(result, IRDataType.BYTE, -1, -1)
-    }
 
-    private fun funcPeekW(call: PtBuiltinFunctionCall): ExpressionCodeResult {
-        val result = mutableListOf<IRCodeChunkBase>()
-        return if(call.args[0] is PtNumber) {
+        return if(address is PtNumber) {
             val resultRegister = codeGen.registers.nextFree()
-            val address = (call.args[0] as PtNumber).number.toInt()
+            val addressNum = address.number.toInt()
             result += IRCodeChunk(null, null).also {
-                it += IRInstruction(Opcode.LOADM, IRDataType.WORD, reg1 = resultRegister, address = address)
+                it += IRInstruction(Opcode.LOADM, IRDataType.BYTE, reg1 = resultRegister, address = addressNum)
             }
+            pokeM(result, addressNum, call.args[1])
             ExpressionCodeResult(result, IRDataType.BYTE, resultRegister, -1)
         } else {
-            val tr = exprGen.translateExpression(call.args.single())
-            addToResult(result, tr, tr.resultReg, -1)
+            val addressTr = exprGen.translateExpression(address)
+            addToResult(result, addressTr, addressTr.resultReg, -1)
             val resultReg = codeGen.registers.nextFree()
             result += IRCodeChunk(null, null).also {
-                it += IRInstruction(Opcode.LOADI, IRDataType.WORD, reg1 = resultReg, reg2 = tr.resultReg)
-            }
-            ExpressionCodeResult(result, IRDataType.WORD, resultReg, -1)
-        }
-    }
-
-    private fun funcPeek(call: PtBuiltinFunctionCall): ExpressionCodeResult {
-        val result = mutableListOf<IRCodeChunkBase>()
-        return if(call.args[0] is PtNumber) {
-            val resultRegister = codeGen.registers.nextFree()
-            val address = (call.args[0] as PtNumber).number.toInt()
-            result += IRCodeChunk(null, null).also {
-                it += IRInstruction(Opcode.LOADM, IRDataType.BYTE, reg1 = resultRegister, address = address)
-            }
-            ExpressionCodeResult(result, IRDataType.BYTE, resultRegister, -1)
-        } else {
-            val tr = exprGen.translateExpression(call.args.single())
-            addToResult(result, tr, tr.resultReg, -1)
-            val resultReg = codeGen.registers.nextFree()
-            result += IRCodeChunk(null, null).also {
-                it += IRInstruction(Opcode.LOADI, IRDataType.BYTE, reg1 = resultReg, reg2 = tr.resultReg)
+                it += IRInstruction(Opcode.LOADI, IRDataType.BYTE, reg1 = resultReg, reg2 = addressTr.resultReg)
             }
+            pokeI(result, addressTr.resultReg, call.args[1])
             ExpressionCodeResult(result, IRDataType.BYTE, resultReg, -1)
         }
     }
 
+
     private fun funcMemory(call: PtBuiltinFunctionCall): ExpressionCodeResult {
         val name = (call.args[0] as PtString).value
         val code = IRCodeChunk(null, null)
@@ -534,6 +615,7 @@ internal class BuiltinFuncGen(private val codeGen: IRCodeGen, private val exprGe
     private fun funcLsb(call: PtBuiltinFunctionCall): ExpressionCodeResult {
         return exprGen.translateExpression(call.args.single())
         // note: if a word result is needed, the upper byte is cleared by the typecast that follows. No need to do it here.
+        // ....To be more strict, maybe we should introduce a new result register that is of type .b?
     }
 
     private fun funcMsb(call: PtBuiltinFunctionCall): ExpressionCodeResult {
@@ -541,25 +623,176 @@ internal class BuiltinFuncGen(private val codeGen: IRCodeGen, private val exprGe
         val tr = exprGen.translateExpression(call.args.single())
         addToResult(result, tr, tr.resultReg, -1)
         val resultReg = codeGen.registers.nextFree()
-        result += IRCodeChunk(null, null).also {
-            it += IRInstruction(Opcode.MSIG, IRDataType.BYTE, reg1 = resultReg, reg2 = tr.resultReg)
-        }
+        addInstr(result, IRInstruction(Opcode.MSIG, IRDataType.BYTE, reg1 = resultReg, reg2 = tr.resultReg), null)
         // note: if a word result is needed, the upper byte is cleared by the typecast that follows. No need to do it here.
         return ExpressionCodeResult(result, IRDataType.BYTE, resultReg, -1)
     }
 
-    private fun funcRolRor(opcode: Opcode, call: PtBuiltinFunctionCall): ExpressionCodeResult {
-        val vmDt = irType(call.args[0].type)
+    private fun funcRolRor(call: PtBuiltinFunctionCall): ExpressionCodeResult {
         val result = mutableListOf<IRCodeChunkBase>()
-        val tr = exprGen.translateExpression(call.args[0])
-        addToResult(result, tr, tr.resultReg, -1)
-        result += IRCodeChunk(null, null).also {
-            it += IRInstruction(opcode, vmDt, reg1 = tr.resultReg)
+        val arg = call.args[0]
+        val vmDt = irType(arg.type)
+        val opcodeMemAndReg = when(call.name) {
+            "rol" -> Opcode.ROXLM to Opcode.ROXL
+            "ror" -> Opcode.ROXRM to Opcode.ROXR
+            "rol2" -> Opcode.ROLM to Opcode.ROL
+            "ror2" -> Opcode.RORM to Opcode.ROR
+            else -> throw AssemblyError("wrong func")
         }
-        result += assignRegisterTo(call.args[0], tr.resultReg)
+
+        val ident = arg as? PtIdentifier
+        if(ident!=null) {
+            addInstr(result, IRInstruction(opcodeMemAndReg.first, vmDt, labelSymbol = ident.name), null)
+            return ExpressionCodeResult(result, vmDt, -1, -1)
+        }
+
+        val memAddr  = (arg as? PtMemoryByte)?.address?.asConstInteger()
+        if(memAddr!=null) {
+            addInstr(result, IRInstruction(opcodeMemAndReg.first, vmDt, address = memAddr), null)
+            return ExpressionCodeResult(result, vmDt, -1, -1)
+        }
+
+        val arr = (arg as? PtArrayIndexer)
+        val index = arr?.index?.asConstInteger()
+        if(arr!=null && index!=null) {
+            val variable = arr.variable.name
+            val itemsize = codeGen.program.memsizer.memorySize(arr.type)
+            addInstr(result, IRInstruction(opcodeMemAndReg.first, vmDt, labelSymbol = variable, symbolOffset = index*itemsize), null)
+            return ExpressionCodeResult(result, vmDt, -1, -1)
+        }
+
+        val opcode = opcodeMemAndReg.second
+        val saveCarry = opcode in OpcodesThatDependOnCarry && !arg.isSimple()
+        if(saveCarry)
+            addInstr(result, IRInstruction(Opcode.PUSHST), null)    // save Carry
+        val tr = exprGen.translateExpression(arg)
+        addToResult(result, tr, tr.resultReg, -1)
+        if(saveCarry)
+            addInstr(result, IRInstruction(Opcode.POPST), null)
+        addInstr(result, IRInstruction(opcode, vmDt, reg1 = tr.resultReg), null)
+        if(saveCarry)
+            addInstr(result, IRInstruction(Opcode.PUSHST), null)    // save Carry
+        result += assignRegisterTo(arg, tr.resultReg)
+        if(saveCarry)
+            addInstr(result, IRInstruction(Opcode.POPST), null)
         return ExpressionCodeResult(result, vmDt, -1, -1)
     }
 
+    private fun funcSetLsbMsb(call: PtBuiltinFunctionCall, msb: Boolean): ExpressionCodeResult {
+        val result = mutableListOf<IRCodeChunkBase>()
+        val target = call.args[0]
+        val isConstZeroValue = call.args[1].asConstInteger()==0
+        when(target) {
+            is PtIdentifier -> {
+                if(isConstZeroValue) {
+                    result += IRCodeChunk(null, null).also {
+                        val pointerReg = codeGen.registers.nextFree()
+                        it += IRInstruction(Opcode.LOAD, IRDataType.WORD, reg1 = pointerReg, labelSymbol = target.name)
+                        if (msb)
+                            it += IRInstruction(Opcode.INC, IRDataType.WORD, reg1 = pointerReg)
+                        it += IRInstruction(Opcode.STOREZI, IRDataType.BYTE, reg1 = pointerReg)
+                    }
+                } else {
+                    val valueTr = exprGen.translateExpression(call.args[1])
+                    addToResult(result, valueTr, valueTr.resultReg, -1)
+                    result += IRCodeChunk(null, null).also {
+                        val pointerReg = codeGen.registers.nextFree()
+                        it += IRInstruction(Opcode.LOAD, IRDataType.WORD, reg1 = pointerReg, labelSymbol = target.name)
+                        if (msb)
+                            it += IRInstruction(Opcode.INC, IRDataType.WORD, reg1 = pointerReg)
+                        it += IRInstruction(Opcode.STOREI, IRDataType.BYTE, reg1 = valueTr.resultReg, reg2 = pointerReg)
+                    }
+                }
+            }
+            is PtArrayIndexer -> {
+                if(target.splitWords) {
+                    // lsb/msb in split arrays, element index 'size' is always 1
+                    val constIndex = target.index.asConstInteger()
+                    val varName = target.variable.name + if(msb) "_msb" else "_lsb"
+                    if(isConstZeroValue) {
+                        if(constIndex!=null) {
+                            val offsetReg = codeGen.registers.nextFree()
+                            result += IRCodeChunk(null, null).also {
+                                it += IRInstruction(Opcode.LOAD, IRDataType.BYTE, reg1=offsetReg, immediate = constIndex)
+                                it += IRInstruction(Opcode.STOREZX, IRDataType.BYTE, reg1=offsetReg, labelSymbol = varName)
+                            }
+                        } else {
+                            val indexTr = exprGen.translateExpression(target.index)
+                            addToResult(result, indexTr, indexTr.resultReg, -1)
+                            result += IRCodeChunk(null, null).also {
+                                it += IRInstruction(Opcode.STOREZX, IRDataType.BYTE, reg1=indexTr.resultReg, labelSymbol = varName)
+                            }
+                        }
+                    } else {
+                        val valueTr = exprGen.translateExpression(call.args[1])
+                        addToResult(result, valueTr, valueTr.resultReg, -1)
+                        if(constIndex!=null) {
+                            val offsetReg = codeGen.registers.nextFree()
+                            result += IRCodeChunk(null, null).also {
+                                it += IRInstruction(Opcode.LOAD, IRDataType.BYTE, reg1=offsetReg, immediate = constIndex)
+                                it += IRInstruction(Opcode.STOREX, IRDataType.BYTE, reg1=valueTr.resultReg, reg2=offsetReg, labelSymbol = varName)
+                            }
+                        } else {
+                            val indexTr = exprGen.translateExpression(target.index)
+                            addToResult(result, indexTr, indexTr.resultReg, -1)
+                            result += IRCodeChunk(null, null).also {
+                                it += IRInstruction(Opcode.STOREX, IRDataType.BYTE, reg1=valueTr.resultReg, reg2=indexTr.resultReg, labelSymbol = varName)
+                            }
+                        }
+                    }
+                }
+                else {
+                    val eltSize = codeGen.program.memsizer.memorySize(target.type)
+                    val constIndex = target.index.asConstInteger()
+                    if(isConstZeroValue) {
+                        if(constIndex!=null) {
+                            val offsetReg = codeGen.registers.nextFree()
+                            val offset = eltSize*constIndex + if(msb) 1 else 0
+                            result += IRCodeChunk(null, null).also {
+                                it += IRInstruction(Opcode.LOAD, IRDataType.BYTE, reg1=offsetReg, immediate = offset)
+                                it += IRInstruction(Opcode.STOREZX, IRDataType.BYTE, reg1=offsetReg, labelSymbol = target.variable.name)
+                            }
+                        } else {
+                            val indexTr = exprGen.translateExpression(target.index)
+                            addToResult(result, indexTr, indexTr.resultReg, -1)
+                            result += IRCodeChunk(null, null).also {
+                                if(eltSize>1)
+                                    it += codeGen.multiplyByConst(IRDataType.BYTE, indexTr.resultReg, eltSize)
+                                if(msb)
+                                    it += IRInstruction(Opcode.INC, IRDataType.BYTE, reg1=indexTr.resultReg)
+                                it += IRInstruction(Opcode.STOREZX, IRDataType.BYTE, reg1=indexTr.resultReg, labelSymbol = target.variable.name)
+                            }
+                        }
+                    } else {
+                        val valueTr = exprGen.translateExpression(call.args[1])
+                        addToResult(result, valueTr, valueTr.resultReg, -1)
+                        if(constIndex!=null) {
+                            val offsetReg = codeGen.registers.nextFree()
+                            val offset = eltSize*constIndex + if(msb) 1 else 0
+                            result += IRCodeChunk(null, null).also {
+                                it += IRInstruction(Opcode.LOAD, IRDataType.BYTE, reg1=offsetReg, immediate = offset)
+                                it += IRInstruction(Opcode.STOREX, IRDataType.BYTE, reg1=valueTr.resultReg, reg2=offsetReg, labelSymbol = target.variable.name)
+                            }
+                        } else {
+                            val indexTr = exprGen.translateExpression(target.index)
+                            addToResult(result, indexTr, indexTr.resultReg, -1)
+                            result += IRCodeChunk(null, null).also {
+                                if(eltSize>1)
+                                    it += codeGen.multiplyByConst(IRDataType.BYTE, indexTr.resultReg, eltSize)
+                                if(msb)
+                                    it += IRInstruction(Opcode.INC, IRDataType.BYTE, reg1=indexTr.resultReg)
+                                it += IRInstruction(Opcode.STOREX, IRDataType.BYTE, reg1=valueTr.resultReg, reg2=indexTr.resultReg, labelSymbol = target.variable.name)
+                            }
+                        }
+                    }
+                }
+            }
+            else -> throw AssemblyError("weird target for setlsb/setmsb: $target")
+        }
+        return ExpressionCodeResult(result, IRDataType.WORD, -1, -1)
+    }
+
+
     private fun assignRegisterTo(target: PtExpression, register: Int): IRCodeChunks {
         val assignment = PtAssignment(target.position)
         val assignTarget = PtAssignTarget(target.position)

codeGenIntermediate/src/prog8/codegen/intermediate/IRPeepholeOptimizer.kt

@@ -45,7 +45,8 @@ class IRPeepholeOptimizer(private val irprog: IRProgram) {
                         val indexedInstructions = chunk1.instructions.withIndex()
                             .map { IndexedValue(it.index, it.value) }
                         val changed = removeNops(chunk1, indexedInstructions)
-                                || removeDoubleLoadsAndStores(chunk1, indexedInstructions)       // TODO not yet implemented
+                                || replaceConcatZeroMsbWithExt(chunk1, indexedInstructions)
+                                || removeDoubleLoadsAndStores(chunk1, indexedInstructions)
                                 || removeUselessArithmetic(chunk1, indexedInstructions)
                                 || removeNeedlessCompares(chunk1, indexedInstructions)
                                 || removeWeirdBranches(chunk1, chunk2, indexedInstructions)
@@ -63,6 +64,22 @@ class IRPeepholeOptimizer(private val irprog: IRProgram) {
         irprog.linkChunks()  // re-link
     }
 
+    private fun replaceConcatZeroMsbWithExt(chunk: IRCodeChunk, indexedInstructions: List<IndexedValue<IRInstruction>>): Boolean {
+        var changed = false
+        indexedInstructions.reversed().forEach { (idx, ins) ->
+            if (ins.opcode == Opcode.CONCAT) {
+                // if the previous instruction loads a zero in the msb, this can be turned into EXT.B instead
+                val prev = indexedInstructions[idx-1].value
+                if(prev.opcode==Opcode.LOAD && prev.immediate==0 && prev.reg1==ins.reg2) {
+                    chunk.instructions[idx] = IRInstruction(Opcode.EXT, IRDataType.BYTE, reg1 = ins.reg1, reg2 = ins.reg3)
+                    chunk.instructions.removeAt(idx-1)
+                    changed = true
+                }
+            }
+        }
+        return changed
+    }
+
     private fun removeEmptyChunks(sub: IRSubroutine) {
         if(sub.chunks.isEmpty())
             return
@@ -70,7 +87,7 @@ class IRPeepholeOptimizer(private val irprog: IRProgram) {
         /*
         Empty Code chunk with label ->
             If next chunk has no label -> move label to next chunk, remove original
-            If next chunk has label -> label name should be the same, remove original. Otherwise FOR NOW leave it in place. (TODO: merge both labels into 1)
+            If next chunk has label -> label name should be the same, remove original. Otherwise merge both labels into 1.
             If is last chunk -> keep chunk in place because of the label.
         Empty Code chunk without label ->
             should not have been generated! ERROR.
@@ -79,6 +96,7 @@ class IRPeepholeOptimizer(private val irprog: IRProgram) {
 
         val relabelChunks = mutableListOf<Pair<Int, String>>()
         val removeChunks = mutableListOf<Int>()
+        val replaceLabels = mutableMapOf<String, String>()
 
         sub.chunks.withIndex().forEach { (index, chunk) ->
             if(chunk is IRCodeChunk && chunk.instructions.isEmpty()) {
@@ -92,10 +110,18 @@ class IRPeepholeOptimizer(private val irprog: IRProgram) {
                             relabelChunks += Pair(index + 1, chunk.label!!)
                             removeChunks += index
                         } else {
-                            if (chunk.label == nextchunk.label)
-                                removeChunks += index
-                            else {
-                                // TODO: merge labels on same chunk
+                            // merge both labels into 1 except if this is the label chunk at the start of the subroutine
+                            if(index>0) {
+                                if (chunk.label == nextchunk.label)
+                                    removeChunks += index
+                                else {
+                                    removeChunks += index
+                                    replaceLabels[chunk.label!!] = nextchunk.label!!
+                                    replaceLabels.entries.forEach { (key, value) ->
+                                        if (value == chunk.label)
+                                            replaceLabels[key] = nextchunk.label!!
+                                    }
+                                }
                             }
                         }
                     }
@@ -105,10 +131,32 @@ class IRPeepholeOptimizer(private val irprog: IRProgram) {
 
         relabelChunks.forEach { (index, label) ->
             val chunk = IRCodeChunk(label, null)
-            chunk.instructions += sub.chunks[index].instructions
+            val subChunk = sub.chunks[index]
+            chunk.instructions += subChunk.instructions
+            if(subChunk is IRCodeChunk)
+                chunk.appendSrcPositions(subChunk.sourceLinesPositions)
             sub.chunks[index] = chunk
         }
         removeChunks.reversed().forEach { index -> sub.chunks.removeAt(index) }
+
+        sub.chunks.forEach { chunk ->
+            chunk.instructions.withIndex().forEach { (idx, instr) ->
+                instr.labelSymbol?.let {
+                    if(instr.opcode in OpcodesThatBranch) {
+                        replaceLabels.forEach { (from, to) ->
+                            if (it == from) {
+                                chunk.instructions[idx] = instr.copy(labelSymbol = to)
+                            }
+                            else {
+                                val actualPrefix = "$from."
+                                if (it.startsWith(actualPrefix))
+                                    chunk.instructions[idx] = instr.copy(labelSymbol = "$to.")
+                            }
+                        }
+                    }
+                }
+            }
+        }
     }
 
     private fun joinChunks(sub: IRSubroutine) {
@@ -140,6 +188,8 @@ class IRPeepholeOptimizer(private val irprog: IRProgram) {
                     if(mayJoinCodeChunks(lastChunk, candidate)) {
                         lastChunk.instructions += candidate.instructions
                         lastChunk.next = candidate.next
+                        if(lastChunk is IRCodeChunk)
+                            lastChunk.appendSrcPositions(candidate.sourceLinesPositions)
                     }
                     else
                         chunks += candidate
@@ -274,14 +324,16 @@ class IRPeepholeOptimizer(private val irprog: IRProgram) {
         indexedInstructions.reversed().forEach { (idx, ins) ->
             if(idx>0 && idx<(indexedInstructions.size-1) && ins.opcode==Opcode.CMPI && ins.immediate==0) {
                 val previous = indexedInstructions[idx-1].value
-                if(previous.opcode in OpcodesThatSetStatusbitsIncludingCarry) {
-                    chunk.instructions.removeAt(idx)
-                    changed = true
-                } else if(previous.opcode in OpcodesThatSetStatusbitsButNotCarry) {
-                    val next = indexedInstructions[idx+1].value
-                    if(next.opcode !in arrayOf(Opcode.BSTCC, Opcode.BSTCS, Opcode.BSTPOS, Opcode.BSTNEG)) {
+                if(previous.reg1==ins.reg1) {
+                    if (previous.opcode in OpcodesThatSetStatusbitsIncludingCarry) {
                         chunk.instructions.removeAt(idx)
                         changed = true
+                    } else if (previous.opcode in OpcodesThatSetStatusbitsButNotCarry) {
+                        val next = indexedInstructions[idx + 1].value
+                        if (next.opcode !in OpcodesThatDependOnCarry) {
+                            chunk.instructions.removeAt(idx)
+                            changed = true
+                        }
                     }
                 }
             }
@@ -358,18 +410,21 @@ class IRPeepholeOptimizer(private val irprog: IRProgram) {
     }
 
     private fun removeDoubleLoadsAndStores(chunk: IRCodeChunk, indexedInstructions: List<IndexedValue<IRInstruction>>): Boolean {
+        return false
+
+/*
         var changed = false
         indexedInstructions.forEach { (idx, ins) ->
 
             // TODO: detect multiple loads to the same target registers, only keep first (if source is not I/O memory)
             // TODO: detect multiple stores to the same target, only keep first (if target is not I/O memory)
             // TODO: detect multiple float ffrom/fto to the same target, only keep first
-            // TODO: detect multiple sequential rnd with same reg1, only keep one
             // TODO: detect subsequent same xors/nots/negs, remove the pairs completely as they cancel out
             // TODO: detect multiple same ands, ors; only keep first
             // TODO: (hard) detect multiple registers being assigned the same value (and not changed) - use only 1 of them
             // ...
         }
         return changed
+*/
     }
 }

codeGenIntermediate/src/prog8/codegen/intermediate/IRUnusedCodeRemover.kt

@@ -1,7 +1,6 @@
 package prog8.codegen.intermediate
 
 import prog8.code.core.IErrorReporter
-import prog8.code.core.SourceCode.Companion.libraryFilePrefix
 import prog8.intermediate.*
 
 
@@ -25,18 +24,29 @@ class IRUnusedCodeRemover(
     }
 
     private fun pruneSymboltable(blockLabel: String) {
-        // we could clean up the SymbolTable as well, but ONLY if these symbols aren't referenced somewhere still in an instruction
+        // we could clean up the SymbolTable as well, but ONLY if these symbols aren't referenced somewhere still in an instruction or variable initializer value
         val prefix = "$blockLabel."
         val blockVars = irprog.st.allVariables().filter { it.name.startsWith(prefix) }
         blockVars.forEach { stVar ->
-            irprog. allSubs().flatMap { it.chunks }.forEach { chunk ->
+            irprog.allSubs().flatMap { it.chunks }.forEach { chunk ->
                 chunk.instructions.forEach { ins ->
                     if(ins.labelSymbol == stVar.name) {
-                        return
+                        return  // symbol occurs in an instruction
                     }
                 }
             }
+
+            irprog.st.allVariables().forEach { variable ->
+                val initValue = variable.onetimeInitializationArrayValue
+                if(!initValue.isNullOrEmpty()) {
+                    if(initValue.any {
+                        it.addressOfSymbol?.startsWith(blockLabel)==true
+                    })
+                        return   // symbol occurs in an initializer value (address-of this symbol)_
+                }
+            }
         }
+
         irprog.st.removeTree(blockLabel)
     }
 
@@ -50,8 +60,8 @@ class IRUnusedCodeRemover(
         irprog.blocks.forEach { block ->
             block.children.filterIsInstance<IRSubroutine>().reversed().forEach { sub ->
                 if(sub.isEmpty()) {
-                    if(!sub.position.file.startsWith(libraryFilePrefix)) {
-                        errors.warn("unused subroutine ${sub.label}", sub.position)
+                    if(!block.options.ignoreUnused) {
+                        errors.info("unused subroutine '${sub.label}'", sub.position)
                     }
                     block.children.remove(sub)
                     irprog.st.removeTree(sub.label)
@@ -71,8 +81,8 @@ class IRUnusedCodeRemover(
         irprog.blocks.forEach { block ->
             block.children.filterIsInstance<IRAsmSubroutine>().reversed().forEach { sub ->
                 if(sub.isEmpty()) {
-                    if(!sub.position.file.startsWith(libraryFilePrefix)) {
-                        errors.warn("unused asmsubroutine ${sub.label}", sub.position)
+                    if(!block.options.ignoreUnused) {
+                        errors.info("unused subroutine '${sub.label}'", sub.position)
                     }
                     block.children.remove(sub)
                     irprog.st.removeTree(sub.label)
@@ -92,7 +102,7 @@ class IRUnusedCodeRemover(
         // check if asmsub is called from another asmsub
         irprog.blocks.asSequence().forEach { block ->
             block.children.filterIsInstance<IRAsmSubroutine>().forEach { sub ->
-                if (block.forceOutput || block.library)
+                if (block.options.forceOutput || block.library)
                     linkedAsmSubs += sub
                 if (sub.asmChunk.isNotEmpty()) {
                     allSubs.forEach { (label, asmsub) ->
@@ -157,7 +167,13 @@ class IRUnusedCodeRemover(
                 it.next?.let { next -> new += next }
                 it.instructions.forEach { instr ->
                     if (instr.branchTarget == null)
-                        instr.labelSymbol?.let { label -> allLabeledChunks[label]?.let { chunk -> new += chunk } }
+                        instr.labelSymbol?.let { label ->
+                            val chunk = allLabeledChunks[label.substringBeforeLast('.')]
+                            if(chunk!=null)
+                                new+=chunk
+                            else
+                                allLabeledChunks[label]?.let { new += it }
+                        }
                     else
                         new += instr.branchTarget!!
                 }
@@ -204,12 +220,20 @@ class IRUnusedCodeRemover(
                 linkedChunks += chunk
         }
 
+        // make sure that chunks that are only used as a prefix of a label, are also marked as linked
+        linkedChunks.toList().forEach { chunk ->
+            chunk.instructions.forEach {
+                if(it.labelSymbol!=null) {
+                    val chunkName = it.labelSymbol!!.substringBeforeLast('.')
+                    allLabeledChunks[chunkName]?.let { linkedChunks+=it }
+                }
+            }
+        }
+
         return removeUnlinkedChunks(linkedChunks)
     }
 
-    private fun removeUnlinkedChunks(
-        linkedChunks: Set<IRCodeChunkBase>
-    ): Int {
+    private fun removeUnlinkedChunks(linkedChunks: Set<IRCodeChunkBase>): Int {
         var numRemoved = 0
         irprog.foreachSub { sub ->
             sub.chunks.withIndex().reversed().forEach { (index, chunk) ->

codeGenIntermediate/src/prog8/codegen/vm/VmCodeGen.kt

@@ -16,7 +16,7 @@ class VmCodeGen: ICodeGeneratorBackend {
         symbolTable: SymbolTable,
         options: CompilationOptions,
         errors: IErrorReporter
-    ): IAssemblyProgram? {
+    ): IAssemblyProgram {
         val irCodeGen = IRCodeGen(program, symbolTable, options, errors)
         val irProgram = irCodeGen.generate()
         return VmAssemblyProgram(irProgram.name, irProgram)

codeGenIntermediate/test/Dummies.kt

@@ -16,6 +16,8 @@ internal object DummyMemsizer : IMemSizer {
 }
 
 internal object DummyStringEncoder : IStringEncoding {
+    override val defaultEncoding: Encoding = Encoding.ISO
+
     override fun encodeString(str: String, encoding: Encoding): List<UByte> {
         return emptyList()
     }
@@ -25,11 +27,11 @@ internal object DummyStringEncoder : IStringEncoding {
     }
 }
 
-internal class ErrorReporterForTests(private val throwExceptionAtReportIfErrors: Boolean=true, private val keepMessagesAfterReporting: Boolean=false):
-    IErrorReporter {
+internal class ErrorReporterForTests(private val throwExceptionAtReportIfErrors: Boolean=true, private val keepMessagesAfterReporting: Boolean=false): IErrorReporter {
 
     val errors = mutableListOf<String>()
     val warnings = mutableListOf<String>()
+    val infos = mutableListOf<String>()
 
     override fun err(msg: String, position: Position) {
         val text = "${position.toClickableStr()} $msg"
@@ -43,6 +45,12 @@ internal class ErrorReporterForTests(private val throwExceptionAtReportIfErrors:
             warnings.add(text)
     }
 
+    override fun info(msg: String, position: Position) {
+        val text = "${position.toClickableStr()} $msg"
+        if(text !in infos)
+            infos.add(text)
+    }
+
     override fun undefined(symbol: List<String>, position: Position) {
         err("undefined symbol: ${symbol.joinToString(".")}", position)
     }
@@ -50,10 +58,11 @@ internal class ErrorReporterForTests(private val throwExceptionAtReportIfErrors:
     override fun noErrors(): Boolean  = errors.isEmpty()
 
     override fun report() {
+        infos.forEach { println("UNITTEST COMPILATION REPORT: INFO: $it") }
         warnings.forEach { println("UNITTEST COMPILATION REPORT: WARNING: $it") }
         errors.forEach { println("UNITTEST COMPILATION REPORT: ERROR: $it") }
         if(throwExceptionAtReportIfErrors)
-            finalizeNumErrors(errors.size, warnings.size)
+            finalizeNumErrors(errors.size, warnings.size, infos.size)
         if(!keepMessagesAfterReporting) {
             clear()
         }
@@ -62,5 +71,6 @@ internal class ErrorReporterForTests(private val throwExceptionAtReportIfErrors:
     fun clear() {
         errors.clear()
         warnings.clear()
+        infos.clear()
     }
 }

codeGenIntermediate/test/TestIRPeepholeOpt.kt

@@ -8,7 +8,7 @@ import prog8.intermediate.*
 class TestIRPeepholeOpt: FunSpec({
     fun makeIRProgram(chunks: List<IRCodeChunkBase>): IRProgram {
         require(chunks.first().label=="main.start")
-        val block = IRBlock("main", null, false, false, IRBlock.BlockAlignment.NONE, Position.DUMMY)
+        val block = IRBlock("main", false, IRBlock.Options(), Position.DUMMY)
         val sub = IRSubroutine("main.start", emptyList(), null, Position.DUMMY)
         chunks.forEach { sub += it }
         block += sub
@@ -18,12 +18,13 @@ class TestIRPeepholeOpt: FunSpec({
             CbmPrgLauncherType.NONE,
             ZeropageType.DONTUSE,
             emptyList(),
+            CompilationOptions.AllZeropageAllowed,
             floats = false,
             noSysInit = true,
             compTarget = target,
             loadAddress = target.machine.PROGRAM_LOAD_ADDRESS
         )
-        val prog = IRProgram("test", IRSymbolTable(null), options, target)
+        val prog = IRProgram("test", IRSymbolTable(), options, target)
         prog.addBlock(block)
         prog.linkChunks()
         prog.validate()
@@ -52,9 +53,9 @@ class TestIRPeepholeOpt: FunSpec({
 
     test("remove jmp to label below") {
         val c1 = IRCodeChunk("main.start", null)
-        c1 += IRInstruction(Opcode.JUMP, labelSymbol = "label")  // removed, but chunk stays because of label
+        c1 += IRInstruction(Opcode.JUMP, labelSymbol = "label")
         val c2 = IRCodeChunk("label", null)
-        c2 += IRInstruction(Opcode.JUMP, labelSymbol = "label2") // removed, but chunk stays because of label
+        c2 += IRInstruction(Opcode.JUMP, labelSymbol = "label2")
         c2 += IRInstruction(Opcode.NOP)  // removed
         val c3 = IRCodeChunk("label2", null)
         c3 += IRInstruction(Opcode.JUMP, labelSymbol = "label3")
@@ -66,15 +67,13 @@ class TestIRPeepholeOpt: FunSpec({
         irProg.chunks().flatMap { it.instructions }.size shouldBe 5
         val opt = IRPeepholeOptimizer(irProg)
         opt.optimize(true, ErrorReporterForTests())
-        irProg.chunks().size shouldBe 4
+        irProg.chunks().size shouldBe 3
         irProg.chunks()[0].label shouldBe "main.start"
-        irProg.chunks()[1].label shouldBe "label"
-        irProg.chunks()[2].label shouldBe "label2"
-        irProg.chunks()[3].label shouldBe "label3"
+        irProg.chunks()[1].label shouldBe "label2"
+        irProg.chunks()[2].label shouldBe "label3"
         irProg.chunks()[0].isEmpty() shouldBe true
-        irProg.chunks()[1].isEmpty() shouldBe true
-        irProg.chunks()[2].isEmpty() shouldBe false
-        irProg.chunks()[3].isEmpty() shouldBe true
+        irProg.chunks()[1].isEmpty() shouldBe false
+        irProg.chunks()[2].isEmpty() shouldBe true
         val instr = irProg.chunks().flatMap { it.instructions }
         instr.size shouldBe 2
         instr[0].opcode shouldBe Opcode.JUMP

codeGenIntermediate/test/TestVmCodeGen.kt

@@ -19,6 +19,7 @@ class TestVmCodeGen: FunSpec({
             CbmPrgLauncherType.NONE,
             ZeropageType.DONTUSE,
             zpReserved = emptyList(),
+            zpAllowed = CompilationOptions.AllZeropageAllowed,
             floats = true,
             noSysInit = false,
             compTarget = target,
@@ -41,7 +42,7 @@ class TestVmCodeGen: FunSpec({
 //}
         val codegen = VmCodeGen()
         val program = PtProgram("test", DummyMemsizer, DummyStringEncoder)
-        val block = PtBlock("main", null, false, false, false, PtBlock.BlockAlignment.NONE, SourceCode.Generated("test"), Position.DUMMY)
+        val block = PtBlock("main", false, SourceCode.Generated("test"), PtBlock.Options(), Position.DUMMY)
         val sub = PtSub("start", emptyList(), null, Position.DUMMY)
         sub.add(PtVariable("pi", DataType.UBYTE, ZeropageWish.DONTCARE, PtNumber(DataType.UBYTE, 0.0, Position.DUMMY), null, Position.DUMMY))
         sub.add(PtVariable("particleX", DataType.ARRAY_UB, ZeropageWish.DONTCARE, null, 3u, Position.DUMMY))
@@ -91,7 +92,7 @@ class TestVmCodeGen: FunSpec({
         program.add(block)
 
         // define the "cx16.r0" virtual register
-        val cx16block = PtBlock("cx16", null, false, false, false, PtBlock.BlockAlignment.NONE, SourceCode.Generated("test"), Position.DUMMY)
+        val cx16block = PtBlock("cx16", false, SourceCode.Generated("test"), PtBlock.Options(), Position.DUMMY)
         cx16block.add(PtMemMapped("r0", DataType.UWORD, 100u, null, Position.DUMMY))
         program.add(cx16block)
 
@@ -120,7 +121,7 @@ class TestVmCodeGen: FunSpec({
 //}
         val codegen = VmCodeGen()
         val program = PtProgram("test", DummyMemsizer, DummyStringEncoder)
-        val block = PtBlock("main", null, false, false, false, PtBlock.BlockAlignment.NONE, SourceCode.Generated("test"), Position.DUMMY)
+        val block = PtBlock("main", false, SourceCode.Generated("test"), PtBlock.Options(), Position.DUMMY)
         val sub = PtSub("start", emptyList(), null, Position.DUMMY)
         sub.add(PtVariable("f1", DataType.FLOAT, ZeropageWish.DONTCARE, null, null, Position.DUMMY))
         val if1 = PtIfElse(Position.DUMMY)
@@ -183,7 +184,7 @@ class TestVmCodeGen: FunSpec({
 //}
         val codegen = VmCodeGen()
         val program = PtProgram("test", DummyMemsizer, DummyStringEncoder)
-        val block = PtBlock("main", null, false, false, false, PtBlock.BlockAlignment.NONE, SourceCode.Generated("test"), Position.DUMMY)
+        val block = PtBlock("main", false, SourceCode.Generated("test"), PtBlock.Options(), Position.DUMMY)
         val sub = PtSub("start", emptyList(), null, Position.DUMMY)
         sub.add(PtVariable("f1", DataType.FLOAT, ZeropageWish.DONTCARE, null, null, Position.DUMMY))
         val if1 = PtIfElse(Position.DUMMY)
@@ -242,7 +243,7 @@ class TestVmCodeGen: FunSpec({
 //}
         val codegen = VmCodeGen()
         val program = PtProgram("test", DummyMemsizer, DummyStringEncoder)
-        val block = PtBlock("main", null, false, false, false, PtBlock.BlockAlignment.NONE, SourceCode.Generated("test"), Position.DUMMY)
+        val block = PtBlock("main", false, SourceCode.Generated("test"), PtBlock.Options(), Position.DUMMY)
         val sub = PtSub("start", emptyList(), null, Position.DUMMY)
         sub.add(PtVariable("f1", DataType.FLOAT, ZeropageWish.DONTCARE, null, null, Position.DUMMY))
         val if1 = PtIfElse(Position.DUMMY)
@@ -250,7 +251,7 @@ class TestVmCodeGen: FunSpec({
         cmp1.add(PtIdentifier("main.start.f1", DataType.FLOAT, Position.DUMMY))
         cmp1.add(PtNumber(DataType.FLOAT, 42.0, Position.DUMMY))
         if1.add(cmp1)
-        if1.add(PtNodeGroup().also { it.add(PtJump(null, 0xc000u, null, Position.DUMMY)) })
+        if1.add(PtNodeGroup().also { it.add(PtJump(null, 0xc000u, Position.DUMMY)) })
         if1.add(PtNodeGroup())
         sub.add(if1)
         val if2 = PtIfElse(Position.DUMMY)
@@ -258,7 +259,7 @@ class TestVmCodeGen: FunSpec({
         cmp2.add(PtIdentifier("main.start.f1", DataType.FLOAT, Position.DUMMY))
         cmp2.add(PtNumber(DataType.FLOAT, 42.0, Position.DUMMY))
         if2.add(cmp2)
-        if2.add(PtNodeGroup().also { it.add(PtJump(null, 0xc000u, null, Position.DUMMY)) })
+        if2.add(PtNodeGroup().also { it.add(PtJump(null, 0xc000u, Position.DUMMY)) })
         if2.add(PtNodeGroup())
         sub.add(if2)
         block.add(sub)
@@ -289,7 +290,7 @@ class TestVmCodeGen: FunSpec({
 //}
         val codegen = VmCodeGen()
         val program = PtProgram("test", DummyMemsizer, DummyStringEncoder)
-        val block = PtBlock("main", null, false, false, false, PtBlock.BlockAlignment.NONE, SourceCode.Generated("test"), Position.DUMMY)
+        val block = PtBlock("main", false, SourceCode.Generated("test"), PtBlock.Options(), Position.DUMMY)
         val sub = PtSub("start", emptyList(), null, Position.DUMMY)
         sub.add(PtVariable("sb1", DataType.BYTE, ZeropageWish.DONTCARE, null, null, Position.DUMMY))
         val if1 = PtIfElse(Position.DUMMY)
@@ -352,7 +353,7 @@ class TestVmCodeGen: FunSpec({
 //}
         val codegen = VmCodeGen()
         val program = PtProgram("test", DummyMemsizer, DummyStringEncoder)
-        val block = PtBlock("main", null, false, false, false, PtBlock.BlockAlignment.NONE, SourceCode.Generated("test"), Position.DUMMY)
+        val block = PtBlock("main", false, SourceCode.Generated("test"), PtBlock.Options(), Position.DUMMY)
         val sub = PtSub("start", emptyList(), null, Position.DUMMY)
         sub.add(PtVariable("sb1", DataType.BYTE, ZeropageWish.DONTCARE, null, null, Position.DUMMY))
         val if1 = PtIfElse(Position.DUMMY)
@@ -411,7 +412,7 @@ class TestVmCodeGen: FunSpec({
 //}
         val codegen = VmCodeGen()
         val program = PtProgram("test", DummyMemsizer, DummyStringEncoder)
-        val block = PtBlock("main", null, false, false, false, PtBlock.BlockAlignment.NONE, SourceCode.Generated("test"), Position.DUMMY)
+        val block = PtBlock("main", false, SourceCode.Generated("test"), PtBlock.Options(), Position.DUMMY)
         val sub = PtSub("start", emptyList(), null, Position.DUMMY)
         sub.add(PtVariable("ub1", DataType.UBYTE, ZeropageWish.DONTCARE, null, null, Position.DUMMY))
         val if1 = PtIfElse(Position.DUMMY)
@@ -419,7 +420,7 @@ class TestVmCodeGen: FunSpec({
         cmp1.add(PtIdentifier("main.start.ub1", DataType.UBYTE, Position.DUMMY))
         cmp1.add(PtNumber(DataType.UBYTE, 42.0, Position.DUMMY))
         if1.add(cmp1)
-        if1.add(PtNodeGroup().also { it.add(PtJump(null, 0xc000u, null, Position.DUMMY)) })
+        if1.add(PtNodeGroup().also { it.add(PtJump(null, 0xc000u, Position.DUMMY)) })
         if1.add(PtNodeGroup())
         sub.add(if1)
         val if2 = PtIfElse(Position.DUMMY)
@@ -427,7 +428,7 @@ class TestVmCodeGen: FunSpec({
         cmp2.add(PtIdentifier("main.start.ub1", DataType.UBYTE, Position.DUMMY))
         cmp2.add(PtNumber(DataType.UBYTE, 42.0, Position.DUMMY))
         if2.add(cmp2)
-        if2.add(PtNodeGroup().also { it.add(PtJump(null, 0xc000u, null, Position.DUMMY)) })
+        if2.add(PtNodeGroup().also { it.add(PtJump(null, 0xc000u, Position.DUMMY)) })
         if2.add(PtNodeGroup())
         sub.add(if2)
         block.add(sub)
@@ -451,7 +452,7 @@ class TestVmCodeGen: FunSpec({
 //}
         val codegen = VmCodeGen()
         val program = PtProgram("test", DummyMemsizer, DummyStringEncoder)
-        val block = PtBlock("main", null, false, false, false, PtBlock.BlockAlignment.NONE, SourceCode.Generated("test"), Position.DUMMY)
+        val block = PtBlock("main", false, SourceCode.Generated("test"), PtBlock.Options(), Position.DUMMY)
         val romsub = PtAsmSub("routine", 0x5000u, setOf(CpuRegister.Y), emptyList(), emptyList(), false, Position.DUMMY)
         block.add(romsub)
         val sub = PtSub("start", emptyList(), null, Position.DUMMY)
@@ -466,7 +467,11 @@ class TestVmCodeGen: FunSpec({
         val result = codegen.generate(program, st, options, errors) as VmAssemblyProgram
         val irChunks = (result.irProgram.blocks.first().children.single() as IRSubroutine).chunks
         irChunks.size shouldBe 1
-        val callInstr = irChunks.single().instructions.single()
+        irChunks[0].instructions.size shouldBe 2
+        val preparecallInstr = irChunks[0].instructions[0]
+        preparecallInstr.opcode shouldBe Opcode.PREPARECALL
+        preparecallInstr.immediate shouldBe 0
+        val callInstr = irChunks[0].instructions[1]
         callInstr.opcode shouldBe Opcode.CALL
         callInstr.address shouldBe 0x5000
     }

codeOptimizers/build.gradle

@@ -27,16 +27,17 @@ dependencies {
     implementation project(':codeCore')
     implementation project(':compilerAst')
     implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8"
+    implementation "com.michael-bull.kotlin-result:kotlin-result-jvm:1.1.18"
     // implementation "org.jetbrains.kotlin:kotlin-reflect"
 }
 
 sourceSets {
     main {
         java {
-            srcDirs = ["${project.projectDir}/src"]
+            srcDir "${project.projectDir}/src"
         }
         resources {
-            srcDirs = ["${project.projectDir}/res"]
+            srcDir "${project.projectDir}/res"
         }
     }
 }

codeOptimizers/codeOptimizers.iml

@@ -11,5 +11,6 @@
     <orderEntry type="library" name="KotlinJavaRuntime" level="project" />
     <orderEntry type="module" module-name="codeCore" />
     <orderEntry type="module" module-name="compilerAst" />
+    <orderEntry type="library" name="michael.bull.kotlin.result.jvm" level="project" />
   </component>
 </module>

codeOptimizers/src/prog8/optimizer/BinExprSplitter.kt

@@ -1,71 +0,0 @@
-package prog8.optimizer
-
-import prog8.ast.IStatementContainer
-import prog8.ast.Node
-import prog8.ast.Program
-import prog8.ast.expressions.BinaryExpression
-import prog8.ast.statements.AssignTarget
-import prog8.ast.statements.Assignment
-import prog8.ast.statements.AssignmentOrigin
-import prog8.ast.walk.AstWalker
-import prog8.ast.walk.IAstModification
-import prog8.code.core.AugmentAssignmentOperators
-import prog8.code.core.CompilationOptions
-import prog8.code.core.DataType
-import prog8.code.target.VMTarget
-
-
-class BinExprSplitter(private val program: Program, private val options: CompilationOptions) : AstWalker() {
-
-    override fun after(assignment: Assignment, parent: Node): Iterable<IAstModification> {
-
-        if(options.compTarget.name == VMTarget.NAME)
-            return noModifications  // don't split expressions when targeting the vm codegen, it handles nested expressions well
-
-        if(assignment.value.inferType(program) istype DataType.FLOAT && !options.optimizeFloatExpressions)
-            return noModifications
-
-        val binExpr = assignment.value as? BinaryExpression
-        if (binExpr != null) {
-
-            if(binExpr.operator in AugmentAssignmentOperators && isSimpleTarget(assignment.target)) {
-                if(assignment.target isSameAs binExpr.right)
-                    return noModifications
-                if(assignment.target isSameAs binExpr.left) {
-                    if(binExpr.right.isSimple)
-                        return noModifications
-                    val leftBx = binExpr.left as? BinaryExpression
-                    if(leftBx!=null && (!leftBx.left.isSimple || !leftBx.right.isSimple))
-                        return noModifications
-                    val rightBx = binExpr.right as? BinaryExpression
-                    if(rightBx!=null && (!rightBx.left.isSimple || !rightBx.right.isSimple))
-                        return noModifications
-                }
-
-                if(binExpr.right.isSimple) {
-                    val firstAssign = Assignment(assignment.target.copy(), binExpr.left, AssignmentOrigin.OPTIMIZER, binExpr.left.position)
-                    val targetExpr = assignment.target.toExpression()
-                    val augExpr = BinaryExpression(targetExpr, binExpr.operator, binExpr.right, binExpr.right.position)
-                    return listOf(
-                        IAstModification.ReplaceNode(binExpr, augExpr, assignment),
-                        IAstModification.InsertBefore(assignment, firstAssign, assignment.parent as IStatementContainer)
-                    )
-                }
-            }
-
-            // Further unraveling of binary expressions is really complicated here and
-            // often results in much bigger code, thereby defeating the purpose a bit.
-            // All in all this should probably be fixed in a better code generation backend
-            // that doesn't require this at all.
-        }
-
-        return noModifications
-    }
-
-    private fun isSimpleTarget(target: AssignTarget) =
-            if (target.identifier!=null || target.memoryAddress!=null)
-                !target.isIOAddress(options.compTarget.machine)
-            else
-                false
-
-}

codeOptimizers/src/prog8/optimizer/ConstExprEvaluator.kt

@@ -1,17 +1,19 @@
 package prog8.optimizer
 
+import prog8.ast.Program
 import prog8.ast.base.ExpressionError
 import prog8.ast.base.FatalAstException
-import prog8.ast.expressions.Expression
+import prog8.ast.expressions.FunctionCallExpression
 import prog8.ast.expressions.NumericLiteral
 import prog8.code.core.DataType
 import prog8.code.core.IntegerDatatypes
 import prog8.code.core.Position
+import kotlin.math.*
 
 
 class ConstExprEvaluator {
 
-    fun evaluate(left: NumericLiteral, operator: String, right: NumericLiteral): Expression {
+    fun evaluate(left: NumericLiteral, operator: String, right: NumericLiteral): NumericLiteral {
         try {
             return when(operator) {
                 "+" -> plus(left, right)
@@ -19,9 +21,9 @@ class ConstExprEvaluator {
                 "*" -> multiply(left, right)
                 "/" -> divide(left, right)
                 "%" -> remainder(left, right)
-                "&" -> bitwiseand(left, right)
-                "|" -> bitwiseor(left, right)
-                "^" -> bitwisexor(left, right)
+                "&" -> bitwiseAnd(left, right)
+                "|" -> bitwiseOr(left, right)
+                "^" -> bitwiseXor(left, right)
                 "<" -> NumericLiteral.fromBoolean(left < right, left.position)
                 ">" -> NumericLiteral.fromBoolean(left > right, left.position)
                 "<=" -> NumericLiteral.fromBoolean(left <= right, left.position)
@@ -30,6 +32,9 @@ class ConstExprEvaluator {
                 "!=" -> NumericLiteral.fromBoolean(left != right, left.position)
                 "<<" -> shiftedleft(left, right)
                 ">>" -> shiftedright(left, right)
+                "and" -> logicalAnd(left, right)
+                "or" -> logicalOr(left, right)
+                "xor" -> logicalXor(left, right)
                 else -> throw FatalAstException("const evaluation for invalid operator $operator")
             }
         } catch (ax: FatalAstException) {
@@ -37,7 +42,7 @@ class ConstExprEvaluator {
         }
     }
 
-    private fun shiftedright(left: NumericLiteral, amount: NumericLiteral): Expression {
+    private fun shiftedright(left: NumericLiteral, amount: NumericLiteral): NumericLiteral {
         if(left.type !in IntegerDatatypes || amount.type !in IntegerDatatypes)
             throw ExpressionError("cannot compute $left >> $amount", left.position)
         val result =
@@ -48,52 +53,81 @@ class ConstExprEvaluator {
         return NumericLiteral(left.type, result.toDouble(), left.position)
     }
 
-    private fun shiftedleft(left: NumericLiteral, amount: NumericLiteral): Expression {
+    private fun shiftedleft(left: NumericLiteral, amount: NumericLiteral): NumericLiteral {
         if(left.type !in IntegerDatatypes || amount.type !in IntegerDatatypes)
             throw ExpressionError("cannot compute $left << $amount", left.position)
         val result = left.number.toInt().shl(amount.number.toInt())
-        return NumericLiteral(left.type, result.toDouble(), left.position)
+//        when(left.type) {
+//            DataType.BOOL -> result = result and 1
+//            DataType.UBYTE -> result = result and 255
+//            DataType.BYTE -> result = result.toByte().toInt()
+//            DataType.UWORD -> result = result and 65535
+//            DataType.WORD -> result = result.toShort().toInt()
+//            else -> { /* keep as it is */ }
+//        }
+        return NumericLiteral.optimalNumeric(result.toDouble(), left.position)
     }
 
-    private fun bitwisexor(left: NumericLiteral, right: NumericLiteral): NumericLiteral {
+    private fun bitwiseXor(left: NumericLiteral, right: NumericLiteral): NumericLiteral {
         if(left.type== DataType.UBYTE) {
             if(right.type in IntegerDatatypes) {
                 return NumericLiteral(DataType.UBYTE, (left.number.toInt() xor (right.number.toInt() and 255)).toDouble(), left.position)
             }
         } else if(left.type== DataType.UWORD) {
             if(right.type in IntegerDatatypes) {
-                return NumericLiteral(DataType.UWORD, (left.number.toInt() xor right.number.toInt()).toDouble(), left.position)
+                return NumericLiteral(DataType.UWORD, (left.number.toInt() xor right.number.toInt() and 65535).toDouble(), left.position)
+            }
+        } else if(left.type== DataType.LONG) {
+            if(right.type in IntegerDatatypes) {
+                return NumericLiteral.optimalNumeric((left.number.toInt() xor right.number.toInt()).toDouble(), left.position)
             }
         }
         throw ExpressionError("cannot calculate $left ^ $right", left.position)
     }
 
-    private fun bitwiseor(left: NumericLiteral, right: NumericLiteral): NumericLiteral {
+    private fun bitwiseOr(left: NumericLiteral, right: NumericLiteral): NumericLiteral {
         if(left.type== DataType.UBYTE) {
             if(right.type in IntegerDatatypes) {
                 return NumericLiteral(DataType.UBYTE, (left.number.toInt() or (right.number.toInt() and 255)).toDouble(), left.position)
             }
         } else if(left.type== DataType.UWORD) {
             if(right.type in IntegerDatatypes) {
-                return NumericLiteral(DataType.UWORD, (left.number.toInt() or right.number.toInt()).toDouble(), left.position)
+                return NumericLiteral(DataType.UWORD, (left.number.toInt() or right.number.toInt() and 65535).toDouble(), left.position)
+            }
+        } else if(left.type== DataType.LONG) {
+            if(right.type in IntegerDatatypes) {
+                return NumericLiteral.optimalNumeric((left.number.toInt() or right.number.toInt()).toDouble(), left.position)
             }
         }
         throw ExpressionError("cannot calculate $left | $right", left.position)
     }
 
-    private fun bitwiseand(left: NumericLiteral, right: NumericLiteral): NumericLiteral {
+    private fun bitwiseAnd(left: NumericLiteral, right: NumericLiteral): NumericLiteral {
         if(left.type== DataType.UBYTE) {
             if(right.type in IntegerDatatypes) {
                 return NumericLiteral(DataType.UBYTE, (left.number.toInt() and (right.number.toInt() and 255)).toDouble(), left.position)
             }
         } else if(left.type== DataType.UWORD) {
             if(right.type in IntegerDatatypes) {
-                return NumericLiteral(DataType.UWORD, (left.number.toInt() and right.number.toInt()).toDouble(), left.position)
+                return NumericLiteral(DataType.UWORD, (left.number.toInt() and right.number.toInt() and 65535).toDouble(), left.position)
+            }
+        } else if(left.type== DataType.LONG) {
+            if(right.type in IntegerDatatypes) {
+                return NumericLiteral.optimalNumeric((left.number.toInt() and right.number.toInt()).toDouble(), left.position)
             }
         }
         throw ExpressionError("cannot calculate $left & $right", left.position)
     }
 
+    private fun logicalAnd(left: NumericLiteral, right: NumericLiteral): NumericLiteral =
+        NumericLiteral.fromBoolean(left.asBooleanValue and right.asBooleanValue, left.position)
+
+    private fun logicalOr(left: NumericLiteral, right: NumericLiteral): NumericLiteral =
+        NumericLiteral.fromBoolean(left.asBooleanValue or right.asBooleanValue, left.position)
+
+    private fun logicalXor(left: NumericLiteral, right: NumericLiteral): NumericLiteral =
+        NumericLiteral.fromBoolean(left.asBooleanValue xor right.asBooleanValue, left.position)
+
     private fun plus(left: NumericLiteral, right: NumericLiteral): NumericLiteral {
         val error = "cannot add $left and $right"
         return when (left.type) {
@@ -206,4 +240,154 @@ class ConstExprEvaluator {
             else -> throw ExpressionError(error, left.position)
         }
     }
+
+    fun evaluate(call: FunctionCallExpression, program: Program): NumericLiteral? {
+        if(call.target.nameInSource.size!=2)
+            return null  // likely a builtin function, or user function, these get evaluated elsewhere
+        val constArgs = call.args.mapNotNull { it.constValue(program) }
+        if(constArgs.size!=call.args.size)
+            return null
+
+        return when(call.target.nameInSource[0]) {
+            "math" -> evalMath(call, constArgs)
+            "floats" -> evalFloats(call, constArgs)
+            "string" -> evalString(call, constArgs)
+            else -> null
+        }
+    }
+
+    private fun evalFloats(func: FunctionCallExpression, args: List<NumericLiteral>): NumericLiteral? {
+        val result= when(func.target.nameInSource[1]) {
+            "pow" -> args[0].number.pow(args[1].number)
+            "sin" -> sin(args[0].number)
+            "cos" -> cos(args[0].number)
+            "tan" -> tan(args[0].number)
+            "atan" -> atan(args[0].number)
+            "ln" -> ln(args[0].number)
+            "log2" -> log2(args[0].number)
+            "rad" -> args[0].number/360.0 * 2 * PI
+            "deg" -> args[0].number/ 2 / PI * 360.0
+            "round" -> round(args[0].number)
+            "floor" -> floor(args[0].number)
+            "ceil" -> ceil(args[0].number)
+            "minf", "min" -> min(args[0].number, args[1].number)
+            "maxf", "max" -> max(args[0].number, args[1].number)
+            "clampf", "clamp" -> {
+                var value = args[0].number
+                val minimum = args[1].number
+                val maximum = args[2].number
+                if(value<minimum)
+                    value=minimum
+                if(value<maximum)
+                    value
+                else
+                    maximum
+            }
+            else -> null
+        }
+
+        return if(result==null)
+            null
+        else
+            NumericLiteral(DataType.FLOAT, result, func.position)
+    }
+
+    private fun evalMath(func: FunctionCallExpression, args: List<NumericLiteral>): NumericLiteral? {
+        return when(func.target.nameInSource[1]) {
+            "sin8u" -> {
+                val value = truncate(128.0 + 127.5 * sin(args.single().number / 256.0 * 2 * PI))
+                NumericLiteral(DataType.UBYTE, value, func.position)
+            }
+            "cos8u" -> {
+                val value = truncate(128.0 + 127.5 * cos(args.single().number / 256.0 * 2 * PI))
+                NumericLiteral(DataType.UBYTE, value, func.position)
+            }
+            "sin8" -> {
+                val value = truncate(127.0  * sin(args.single().number / 256.0 * 2 * PI))
+                NumericLiteral(DataType.BYTE, value, func.position)
+            }
+            "cos8" -> {
+                val value = truncate(127.0  * cos(args.single().number / 256.0 * 2 * PI))
+                NumericLiteral(DataType.BYTE, value, func.position)
+            }
+            "sinr8u" -> {
+                val value = truncate(128.0 + 127.5 * sin(args.single().number / 180.0 * 2 * PI))
+                NumericLiteral(DataType.UBYTE, value, func.position)
+            }
+            "cosr8u" -> {
+                val value = truncate(128.0 + 127.5 * cos(args.single().number / 180.0 * 2 * PI))
+                NumericLiteral(DataType.UBYTE, value, func.position)
+            }
+            "sinr8" -> {
+                val value = truncate(127.0  * sin(args.single().number / 180.0 * 2 * PI))
+                NumericLiteral(DataType.BYTE, value, func.position)
+            }
+            "cosr8" -> {
+                val value = truncate(127.0  * cos(args.single().number / 180.0 * 2 * PI))
+                NumericLiteral(DataType.BYTE, value, func.position)
+            }
+            "log2" -> {
+                val value = truncate(log2(args.single().number))
+                NumericLiteral(DataType.UBYTE, value, func.position)
+            }
+            "log2w" -> {
+                val value = truncate(log2(args.single().number))
+                NumericLiteral(DataType.UWORD, value, func.position)
+            }
+            "atan2" -> {
+                val x1f = args[0].number
+                val y1f = args[1].number
+                val x2f = args[2].number
+                val y2f = args[3].number
+                var radians = atan2(y2f-y1f, x2f-x1f)
+                if(radians<0)
+                    radians+=2*PI
+                NumericLiteral(DataType.UWORD, floor(radians/2.0/PI*256.0), func.position)
+            }
+            "diff" -> {
+                val n1 = args[0].number
+                val n2 = args[1].number
+                val value = if(n1>n2) n1-n2 else n2-n1
+                NumericLiteral(DataType.UBYTE, value, func.position)
+            }
+            "diffw" -> {
+                val n1 = args[0].number
+                val n2 = args[1].number
+                val value = if(n1>n2) n1-n2 else n2-n1
+                NumericLiteral(DataType.UWORD, value, func.position)
+            }
+            else -> null
+        }
+    }
+
+    private fun evalString(func: FunctionCallExpression, args: List<NumericLiteral>): NumericLiteral? {
+        return when(func.target.nameInSource[1]) {
+            "isdigit" -> {
+                val char = args[0].number.toInt()
+                NumericLiteral.fromBoolean(char in 48..57, func.position)
+            }
+            "isupper" -> {
+                // shifted petscii has 2 ranges that contain the upper case letters... 97-122 and 193-218
+                val char = args[0].number.toInt()
+                NumericLiteral.fromBoolean(char in 97..122 || char in 193..218, func.position)
+            }
+            "islower" -> {
+                val char = args[0].number.toInt()
+                NumericLiteral.fromBoolean(char in 65..90, func.position)
+            }
+            "isletter" -> {
+                val char = args[0].number.toInt()
+                NumericLiteral.fromBoolean(char in 65..90 || char in 97..122 || char in 193..218, func.position)
+            }
+            "isspace" -> {
+                val char = args[0].number.toInt()
+                NumericLiteral.fromBoolean(char in arrayOf(32, 13, 9, 10, 141, 160), func.position)
+            }
+            "isprint" -> {
+                val char = args[0].number.toInt()
+                NumericLiteral.fromBoolean(char in 32..127 || char>=160, func.position)
+            }
+            else -> null
+        }
+    }
 }

codeOptimizers/src/prog8/optimizer/ConstantFoldingOptimizer.kt

@@ -2,29 +2,47 @@ package prog8.optimizer
 
 import prog8.ast.Node
 import prog8.ast.Program
-import prog8.ast.base.FatalAstException
 import prog8.ast.expressions.*
 import prog8.ast.maySwapOperandOrder
-import prog8.ast.statements.ForLoop
-import prog8.ast.statements.RepeatLoop
-import prog8.ast.statements.VarDecl
-import prog8.ast.statements.VarDeclType
+import prog8.ast.statements.*
 import prog8.ast.walk.AstWalker
 import prog8.ast.walk.IAstModification
 import prog8.code.core.AssociativeOperators
 import prog8.code.core.DataType
+import prog8.code.core.IErrorReporter
 import kotlin.math.floor
 
 
-class ConstantFoldingOptimizer(private val program: Program) : AstWalker() {
+class ConstantFoldingOptimizer(private val program: Program, private val errors: IErrorReporter) : AstWalker() {
+
+    private val evaluator = ConstExprEvaluator()
+
+    override fun after(addressOf: AddressOf, parent: Node): Iterable<IAstModification> {
+        val constAddr = addressOf.constValue(program) ?: return noModifications
+        return listOf(IAstModification.ReplaceNode(addressOf, constAddr, parent))
+    }
 
     override fun before(memread: DirectMemoryRead, parent: Node): Iterable<IAstModification> {
-        // @( &thing )  -->  thing
+        // @( &thing )  -->  thing  (but only if thing is a byte type!)
         val addrOf = memread.addressExpression as? AddressOf
-        return if(addrOf!=null)
-            listOf(IAstModification.ReplaceNode(memread, addrOf.identifier, parent))
-        else
-            noModifications
+        if(addrOf!=null) {
+            if(addrOf.identifier.inferType(program).isBytes)
+                return listOf(IAstModification.ReplaceNode(memread, addrOf.identifier, parent))
+        }
+        return noModifications
+    }
+
+    override fun after(numLiteral: NumericLiteral, parent: Node): Iterable<IAstModification> {
+        if(parent is Assignment) {
+            val iDt = parent.target.inferType(program)
+            if(iDt.isKnown && !iDt.isBool && !iDt.istype(numLiteral.type)) {
+                val casted = numLiteral.cast(iDt.getOr(DataType.UNDEFINED))
+                if(casted.isValid) {
+                    return listOf(IAstModification.ReplaceNode(numLiteral, casted.value!!, parent))
+                }
+            }
+        }
+        return noModifications
     }
 
     override fun after(containment: ContainmentCheck, parent: Node): Iterable<IAstModification> {
@@ -79,6 +97,8 @@ class ConstantFoldingOptimizer(private val program: Program) : AstWalker() {
             else if(expr.operator=="*" && rightconst!=null && expr.left is StringLiteral) {
                 // mutiply a string.
                 val part = expr.left as StringLiteral
+                if(part.value.isEmpty())
+                    errors.warn("resulting string has length zero", part.position)
                 val newStr = StringLiteral(part.value.repeat(rightconst.number.toInt()), part.encoding, expr.position)
                 return listOf(IAstModification.ReplaceNode(expr, newStr, parent))
             }
@@ -86,7 +106,8 @@ class ConstantFoldingOptimizer(private val program: Program) : AstWalker() {
 
         if(expr.operator=="==" && rightconst!=null) {
             val leftExpr = expr.left as? BinaryExpression
-            if(leftExpr!=null) {
+            // only do this shuffling when the LHS is not a constant itself (otherwise problematic nested replacements)
+            if(leftExpr?.constValue(program) != null) {
                 val leftRightConst = leftExpr.right.constValue(program)
                 if(leftRightConst!=null) {
                     when (leftExpr.operator) {
@@ -133,9 +154,8 @@ class ConstantFoldingOptimizer(private val program: Program) : AstWalker() {
             }
         }
 
-        val evaluator = ConstExprEvaluator()
-
-        // const fold when both operands are a const
+        // const fold when both operands are a const.
+        // if in a chained comparison, that one has to be desugared first though.
         if(leftconst != null && rightconst != null) {
             val result = evaluator.evaluate(leftconst, expr.operator, rightconst)
             modifications += IAstModification.ReplaceNode(expr, result, parent)
@@ -183,10 +203,12 @@ class ConstantFoldingOptimizer(private val program: Program) : AstWalker() {
                         val newExpr = BinaryExpression(leftBinExpr.left, "*", constants, expr.position)
                         return listOf(IAstModification.ReplaceNode(expr, newExpr, parent))
                     } else if (leftBinExpr.operator=="/") {
-                        //  (X / C2) * rightConst   -->  X * (rightConst/C2)
-                        val constants = BinaryExpression(rightconst, "/", c2, c2.position)
-                        val newExpr = BinaryExpression(leftBinExpr.left, "*", constants, expr.position)
-                        return listOf(IAstModification.ReplaceNode(expr, newExpr, parent))
+                        if(expr.inferType(program).istype(DataType.FLOAT)) {
+                            //  (X / C2) * rightConst   -->  X * (rightConst/C2)    only valid for floating point
+                            val constants = BinaryExpression(rightconst, "/", c2, c2.position)
+                            val newExpr = BinaryExpression(leftBinExpr.left, "*", constants, expr.position)
+                            return listOf(IAstModification.ReplaceNode(expr, newExpr, parent))
+                        }
                     }
                 }
             }
@@ -194,7 +216,7 @@ class ConstantFoldingOptimizer(private val program: Program) : AstWalker() {
                 val c2 = leftBinExpr.right.constValue(program)
                 if(c2!=null && leftBinExpr.operator=="/") {
                     // (X / C1) / C2   -->  X / (C1*C2)
-                    // NOTE: do not optimize  (X * C1) / C2   -->  X * (C1/C2)  because this causes precision loss on integers
+                    // NOTE: do not optimize  (X * C1) / C2  for integers,  -->  X * (C1/C2)  because this causes precision loss on integers
                     val constants = BinaryExpression(c2, "*", rightconst, c2.position)
                     val newExpr = BinaryExpression(leftBinExpr.left, "/", constants, expr.position)
                     return listOf(IAstModification.ReplaceNode(expr, newExpr, parent))
@@ -226,16 +248,19 @@ class ConstantFoldingOptimizer(private val program: Program) : AstWalker() {
                 }
                 else if(leftBinExpr.operator=="*" && rightBinExpr.operator=="*"){
                     if (c1 != null && c2 != null && c1==c2) {
-                        //(X * C) <plusmin> (Y * C)  =>  (X <plusmin> Y) * C
-                        val xwithy = BinaryExpression(leftBinExpr.left, expr.operator, rightBinExpr.left, expr.position)
-                        val newExpr = BinaryExpression(xwithy, "*", c1, expr.position)
-                        modifications += IAstModification.ReplaceNode(expr, newExpr, parent)
+                        //(X * C) <plusmin> (Y * C)  =>  (X <plusmin> Y) * C    (only if types of X and Y are the same!)
+                        val xDt = leftBinExpr.left.inferType(program)
+                        val yDt = rightBinExpr.left.inferType(program)
+                        if(xDt==yDt) {
+                            val xwithy = BinaryExpression(leftBinExpr.left, expr.operator, rightBinExpr.left, expr.position)
+                            val newExpr = BinaryExpression(xwithy, "*", c1, expr.position)
+                            modifications += IAstModification.ReplaceNode(expr, newExpr, parent)
+                        }
                     }
                 }
             }
         }
 
-
         return modifications
     }
 
@@ -269,8 +294,13 @@ class ConstantFoldingOptimizer(private val program: Program) : AstWalker() {
         val constvalue = functionCallExpr.constValue(program)
         return if(constvalue!=null)
             listOf(IAstModification.ReplaceNode(functionCallExpr, constvalue, parent))
-        else
-            noModifications
+        else {
+            val const2 = evaluator.evaluate(functionCallExpr, program)
+            return if(const2!=null)
+                listOf(IAstModification.ReplaceNode(functionCallExpr, const2, parent))
+            else
+                noModifications
+        }
     }
 
     override fun after(bfc: BuiltinFunctionCall, parent: Node): Iterable<IAstModification> {
@@ -292,14 +322,14 @@ class ConstantFoldingOptimizer(private val program: Program) : AstWalker() {
                 if(stepLiteral!=null) {
                     val stepCast = stepLiteral.cast(targetDt)
                     if(stepCast.isValid)
-                        stepCast.valueOrZero()
+                        stepCast.value!!
                     else
                         range.step
                 } else {
                     range.step
                 }
 
-            return RangeExpression(fromCast.valueOrZero(), toCast.valueOrZero(), newStep, range.position)
+            return RangeExpression(fromCast.value!!, toCast.value!!, newStep, range.position)
         }
 
         // adjust the datatype of a range expression in for loops to the loop variable.
@@ -344,7 +374,7 @@ class ConstantFoldingOptimizer(private val program: Program) : AstWalker() {
                         return listOf(IAstModification.ReplaceNode(forLoop.iterable, newIter, forLoop))
                 }
             }
-            else -> throw FatalAstException("invalid loopvar datatype $loopvar")
+            else -> { /* nothing for floats, these are not allowed in for loops and will give an error elsewhere */ }
         }
 
         return noModifications
@@ -358,7 +388,7 @@ class ConstantFoldingOptimizer(private val program: Program) : AstWalker() {
                 if(decl.datatype!=DataType.BOOL || valueDt.isnot(DataType.UBYTE)) {
                     val cast = numval.cast(decl.datatype)
                     if (cast.isValid)
-                        return listOf(IAstModification.ReplaceNode(numval, cast.valueOrZero(), decl))
+                        return listOf(IAstModification.ReplaceNode(numval, cast.value!!, decl))
                 }
             }
         }
@@ -375,6 +405,11 @@ class ConstantFoldingOptimizer(private val program: Program) : AstWalker() {
         return noModifications
     }
 
+    override fun after(typecast: TypecastExpression, parent: Node): Iterable<IAstModification> {
+        val constValue = typecast.constValue(program) ?: return noModifications
+        return listOf(IAstModification.ReplaceNode(typecast, constValue, parent))
+    }
+
     private class ShuffleOperands(val expr: BinaryExpression,
                                   val exprOperator: String?,
                                   val subExpr: BinaryExpression,
@@ -484,7 +519,8 @@ class ConstantFoldingOptimizer(private val program: Program) : AstWalker() {
                     return IAstModification.ReplaceNode(expr, change, expr.parent)
                 }
             }
-            else if(expr.operator=="*" && subExpr.operator=="/") {
+            else if(expr.operator=="*" && subExpr.operator=="/" && subExpr.inferType(program).istype(DataType.FLOAT)) {
+                // division optimizations only valid for floats
                 if(leftIsConst) {
                     val change = if(subleftIsConst) {
                         // C1*(C2/V) -> (C1*C2)/V
@@ -587,5 +623,4 @@ class ConstantFoldingOptimizer(private val program: Program) : AstWalker() {
             return null
         }
     }
-
 }

codeOptimizers/src/prog8/optimizer/ConstantIdentifierReplacer.kt

@@ -1,5 +1,7 @@
 package prog8.optimizer
 
+import prog8.ast.IFunctionCall
+import prog8.ast.IStatementContainer
 import prog8.ast.Node
 import prog8.ast.Program
 import prog8.ast.base.FatalAstException
@@ -9,10 +11,17 @@ import prog8.ast.statements.*
 import prog8.ast.walk.AstWalker
 import prog8.ast.walk.IAstModification
 import prog8.code.core.*
+import prog8.compiler.CallGraph
 
 // Fix up the literal value's type to match that of the vardecl
 //   (also check range literal operands types before they get expanded into arrays for instance)
-class VarConstantValueTypeAdjuster(private val program: Program, private val errors: IErrorReporter) : AstWalker() {
+class VarConstantValueTypeAdjuster(
+    private val program: Program,
+    private val options: CompilationOptions,
+    private val errors: IErrorReporter
+) : AstWalker() {
+
+    private val callGraph by lazy { CallGraph(program) }
 
     override fun after(decl: VarDecl, parent: Node): Iterable<IAstModification> {
 
@@ -25,18 +34,86 @@ class VarConstantValueTypeAdjuster(private val program: Program, private val err
                 && declConstValue.type != decl.datatype) {
                 // avoid silent float roundings
                 if(decl.datatype in IntegerDatatypes && declConstValue.type == DataType.FLOAT) {
-                    errors.err("refused rounding of float to avoid loss of precision", decl.value!!.position)
+                    errors.err("refused truncating of float to avoid loss of precision", decl.value!!.position)
                 } else {
                     // cast the numeric literal to the appropriate datatype of the variable
+                    declConstValue.linkParents(decl)
                     val cast = declConstValue.cast(decl.datatype)
                     if (cast.isValid)
-                        return listOf(IAstModification.ReplaceNode(decl.value!!, cast.valueOrZero(), decl))
+                        return listOf(IAstModification.ReplaceNode(decl.value!!, cast.value!!, decl))
                 }
             }
         } catch (x: UndefinedSymbolError) {
             errors.err(x.message, x.position)
         }
 
+        // replace variables by constants, if possible
+        if(options.optimize) {
+            if (decl.sharedWithAsm || decl.type != VarDeclType.VAR || decl.origin != VarDeclOrigin.USERCODE || decl.datatype !in NumericDatatypes)
+                return noModifications
+            if (decl.value != null && decl.value!!.constValue(program) == null)
+                return noModifications
+            val usages = callGraph.usages(decl)
+            val (writes, reads) = usages
+                .partition {
+                    it is InlineAssembly  // can't really tell if it's written to or only read, assume the worst
+                            || it.parent is AssignTarget
+                            || it.parent is ForLoop
+                            || it.parent is AddressOf
+                            || (it.parent as? IFunctionCall)?.target?.nameInSource?.singleOrNull() in InplaceModifyingBuiltinFunctions
+                }
+            val singleAssignment =
+                writes.singleOrNull()?.parent?.parent as? Assignment ?: writes.singleOrNull()?.parent as? Assignment
+            if (singleAssignment == null) {
+                if (writes.isEmpty()) {
+                    if(reads.isEmpty()) {
+                        // variable is never used AT ALL so we just remove it altogether
+                        if("ignore_unused" !in decl.definingBlock.options())
+                            errors.info("removing unused variable '${decl.name}'", decl.position)
+                        return listOf(IAstModification.Remove(decl, parent as IStatementContainer))
+                    }
+                    val declValue = decl.value?.constValue(program)
+                    if (declValue != null) {
+                        // variable is never written to, so it can be replaced with a constant, IF the value is a constant
+                        errors.info("variable is never written to and was replaced by a constant", decl.position)
+                        val const = VarDecl(VarDeclType.CONST, decl.origin, decl.datatype, decl.zeropage, decl.arraysize, decl.name, decl.names, declValue, decl.sharedWithAsm, decl.splitArray, decl.position)
+                        return listOf(
+                            IAstModification.ReplaceNode(decl, const, parent),
+                        )
+                    }
+                }
+            } else {
+                if (singleAssignment.origin == AssignmentOrigin.VARINIT && singleAssignment.value.constValue(program) != null) {
+                    if(reads.isEmpty()) {
+                        // variable is never used AT ALL so we just remove it altogether, including the single assignment
+                        if("ignore_unused" !in decl.definingBlock.options())
+                            errors.info("removing unused variable '${decl.name}'", decl.position)
+                        return listOf(
+                            IAstModification.Remove(decl, parent as IStatementContainer),
+                            IAstModification.Remove(singleAssignment, singleAssignment.parent as IStatementContainer)
+                        )
+                    }
+                    // variable only has a single write and it is the initialization value, so it can be replaced with a constant, IF the value is a constant
+                    errors.info("variable is never written to and was replaced by a constant", decl.position)
+                    val const = VarDecl(VarDeclType.CONST, decl.origin, decl.datatype, decl.zeropage, decl.arraysize, decl.name, decl.names, singleAssignment.value, decl.sharedWithAsm, decl.splitArray, decl.position)
+                    return listOf(
+                        IAstModification.ReplaceNode(decl, const, parent),
+                        IAstModification.Remove(singleAssignment, singleAssignment.parent as IStatementContainer)
+                    )
+                }
+            }
+            /*
+        TODO: need to check if there are no variable usages between the declaration and the assignment (because these rely on the original initialization value)
+        if(writes.size==2) {
+            val firstAssignment = writes[0].parent as? Assignment
+            val secondAssignment = writes[1].parent as? Assignment
+            if(firstAssignment?.origin==AssignmentOrigin.VARINIT && secondAssignment?.value?.constValue(program)!=null) {
+                errors.warn("variable is only assigned once here, consider using this as the initialization value in the declaration instead", secondAssignment.position)
+            }
+        }
+        */
+        }
+
         return noModifications
     }
 
@@ -195,6 +272,14 @@ class VarConstantValueTypeAdjuster(private val program: Program, private val err
 // This is needed because further constant optimizations depend on those.
 internal class ConstantIdentifierReplacer(private val program: Program, private val errors: IErrorReporter, private val compTarget: ICompilationTarget) : AstWalker() {
 
+    override fun before(addressOf: AddressOf, parent: Node): Iterable<IAstModification> {
+        val constValue = addressOf.constValue(program)
+        if(constValue!=null) {
+            return listOf(IAstModification.ReplaceNode(addressOf, constValue, parent))
+        }
+        return noModifications
+    }
+
     override fun after(identifier: IdentifierReference, parent: Node): Iterable<IAstModification> {
         // replace identifiers that refer to const value, with the value itself
         // if it's a simple type and if it's not a left hand side variable
@@ -227,16 +312,20 @@ internal class ConstantIdentifierReplacer(private val program: Program, private
                     listOf(IAstModification.ReplaceNode(arrayIdx, memread, arrayIdx.parent))
                 }
             }
-            return when (cval.type) {
-                in NumericDatatypes -> listOf(
-                    IAstModification.ReplaceNode(
-                        identifier,
-                        NumericLiteral(cval.type, cval.number, identifier.position),
-                        identifier.parent
+            when (cval.type) {
+                in NumericDatatypes -> {
+                    if(parent is AddressOf)
+                        return noModifications      // cannot replace the identifier INSIDE the addr-of here, let's do it later.
+                    return listOf(
+                        IAstModification.ReplaceNode(
+                            identifier,
+                            NumericLiteral(cval.type, cval.number, identifier.position),
+                            identifier.parent
+                        )
                     )
-                )
+                }
                 in PassByReferenceDatatypes -> throw InternalCompilerException("pass-by-reference type should not be considered a constant")
-                else -> noModifications
+                else -> return noModifications
             }
         } catch (x: UndefinedSymbolError) {
             errors.err(x.message, x.position)
@@ -244,14 +333,23 @@ internal class ConstantIdentifierReplacer(private val program: Program, private
         }
     }
 
-    override fun before(decl: VarDecl, parent: Node): Iterable<IAstModification> {
+    override fun after(decl: VarDecl, parent: Node): Iterable<IAstModification> {
         // the initializer value can't refer to the variable itself (recursive definition)
         if(decl.value?.referencesIdentifier(listOf(decl.name)) == true || decl.arraysize?.indexExpr?.referencesIdentifier(listOf(decl.name)) == true) {
             errors.err("recursive var declaration", decl.position)
             return noModifications
         }
 
-        if(decl.type== VarDeclType.CONST || decl.type== VarDeclType.VAR) {
+        if(decl.isArray && decl.type==VarDeclType.MEMORY && decl.value !is IdentifierReference) {
+            val memaddr = decl.value?.constValue(program)
+            if(memaddr!=null && memaddr !== decl.value) {
+                return listOf(IAstModification.SetExpression(
+                    { decl.value = it }, memaddr, decl
+                ))
+            }
+        }
+
+        if(decl.type==VarDeclType.CONST || decl.type==VarDeclType.VAR) {
             if(decl.isArray){
                 val arraysize = decl.arraysize
                 if(arraysize==null) {
@@ -276,101 +374,10 @@ internal class ConstantIdentifierReplacer(private val program: Program, private
                         return listOf(IAstModification.ReplaceNode(decl.value!!, newValue, decl))
                     }
                 }
-                DataType.ARRAY_UB, DataType.ARRAY_B, DataType.ARRAY_UW, DataType.ARRAY_W, DataType.ARRAY_W_SPLIT, DataType.ARRAY_UW_SPLIT -> {
-                    val rangeExpr = decl.value as? RangeExpression
-                    if(rangeExpr!=null) {
-                        // convert the initializer range expression to an actual array
-                        val declArraySize = decl.arraysize?.constIndex()
-                        if(declArraySize!=null && declArraySize!=rangeExpr.size())
-                            errors.err("range expression size (${rangeExpr.size()}) doesn't match declared array size ($declArraySize)", decl.value?.position!!)
-                        val constRange = rangeExpr.toConstantIntegerRange()
-                        if(constRange!=null) {
-                            val eltType = rangeExpr.inferType(program).getOr(DataType.UBYTE)
-                            val newValue = if(eltType in ByteDatatypes) {
-                                ArrayLiteral(InferredTypes.InferredType.known(decl.datatype),
-                                        constRange.map { NumericLiteral(eltType, it.toDouble(), decl.value!!.position) }.toTypedArray(),
-                                        position = decl.value!!.position)
-                            } else {
-                                ArrayLiteral(InferredTypes.InferredType.known(decl.datatype),
-                                        constRange.map { NumericLiteral(eltType, it.toDouble(), decl.value!!.position) }.toTypedArray(),
-                                        position = decl.value!!.position)
-                            }
-                            return listOf(IAstModification.ReplaceNode(decl.value!!, newValue, decl))
-                        }
-                    }
-                    val numericLv = decl.value as? NumericLiteral
-                    if(numericLv!=null && numericLv.type== DataType.FLOAT)
-                        errors.err("arraysize requires only integers here", numericLv.position)
-                    val size = decl.arraysize?.constIndex() ?: return noModifications
-                    if (rangeExpr==null && numericLv!=null) {
-                        // arraysize initializer is empty or a single int, and we know the size; create the arraysize.
-                        val fillvalue = numericLv.number.toInt()
-                        when(decl.datatype){
-                            DataType.ARRAY_UB -> {
-                                if(fillvalue !in 0..255)
-                                    errors.err("ubyte value overflow", numericLv.position)
-                            }
-                            DataType.ARRAY_B -> {
-                                if(fillvalue !in -128..127)
-                                    errors.err("byte value overflow", numericLv.position)
-                            }
-                            DataType.ARRAY_UW -> {
-                                if(fillvalue !in 0..65535)
-                                    errors.err("uword value overflow", numericLv.position)
-                            }
-                            DataType.ARRAY_W -> {
-                                if(fillvalue !in -32768..32767)
-                                    errors.err("word value overflow", numericLv.position)
-                            }
-                            else -> {}
-                        }
-                        // create the array itself, filled with the fillvalue.
-                        val array = Array(size) {fillvalue}.map { NumericLiteral(ArrayToElementTypes.getValue(decl.datatype), it.toDouble(), numericLv.position) }.toTypedArray<Expression>()
-                        val refValue = ArrayLiteral(InferredTypes.InferredType.known(decl.datatype), array, position = numericLv.position)
-                        return listOf(IAstModification.ReplaceNode(decl.value!!, refValue, decl))
-                    }
-                }
-                DataType.ARRAY_F -> {
-                    val rangeExpr = decl.value as? RangeExpression
-                    if(rangeExpr!=null) {
-                        // convert the initializer range expression to an actual array of floats
-                        val declArraySize = decl.arraysize?.constIndex()
-                        if(declArraySize!=null && declArraySize!=rangeExpr.size())
-                            errors.err("range expression size (${rangeExpr.size()}) doesn't match declared array size ($declArraySize)", decl.value?.position!!)
-                        val constRange = rangeExpr.toConstantIntegerRange()
-                        if(constRange!=null) {
-                            val newValue = ArrayLiteral(InferredTypes.InferredType.known(DataType.ARRAY_F),
-                                    constRange.map { NumericLiteral(DataType.FLOAT, it.toDouble(), decl.value!!.position) }.toTypedArray(),
-                                    position = decl.value!!.position)
-                            return listOf(IAstModification.ReplaceNode(decl.value!!, newValue, decl))
-                        }
-                    }
-
-                    val numericLv = decl.value as? NumericLiteral
-                    val size = decl.arraysize?.constIndex() ?: return noModifications
-                    if(rangeExpr==null && numericLv!=null) {
-                        // arraysize initializer is a single int, and we know the size.
-                        val fillvalue = numericLv.number
-                        if (fillvalue < compTarget.machine.FLOAT_MAX_NEGATIVE || fillvalue > compTarget.machine.FLOAT_MAX_POSITIVE)
-                            errors.err("float value overflow", numericLv.position)
-                        else {
-                            // create the array itself, filled with the fillvalue.
-                            val array = Array(size) {fillvalue}.map { NumericLiteral(DataType.FLOAT, it, numericLv.position) }.toTypedArray<Expression>()
-                            val refValue = ArrayLiteral(InferredTypes.InferredType.known(DataType.ARRAY_F), array, position = numericLv.position)
-                            return listOf(IAstModification.ReplaceNode(decl.value!!, refValue, decl))
-                        }
-                    }
-                }
-                DataType.ARRAY_BOOL -> {
-                    val numericLv = decl.value as? NumericLiteral
-                    val size = decl.arraysize?.constIndex() ?: return noModifications
-                    if(numericLv!=null) {
-                        // arraysize initializer is a single int, and we know the size.
-                        val fillvalue = if(numericLv.number==0.0) 0.0 else 1.0
-                        val array = Array(size) {fillvalue}.map { NumericLiteral(DataType.UBYTE, fillvalue, numericLv.position) }.toTypedArray<Expression>()
-                        val refValue = ArrayLiteral(InferredTypes.InferredType.known(DataType.ARRAY_BOOL), array, position = numericLv.position)
-                        return listOf(IAstModification.ReplaceNode(decl.value!!, refValue, decl))
-                    }
+                in ArrayDatatypes -> {
+                    val replacedArrayInitializer = createConstArrayInitializerValue(decl)
+                    if(replacedArrayInitializer!=null)
+                        return listOf(IAstModification.ReplaceNode(decl.value!!, replacedArrayInitializer, decl))
                 }
                 else -> {
                     // nothing to do for this type
@@ -380,4 +387,112 @@ internal class ConstantIdentifierReplacer(private val program: Program, private
 
         return noModifications
     }
+
+    private fun createConstArrayInitializerValue(decl: VarDecl): ArrayLiteral? {
+
+        if(decl.type==VarDeclType.MEMORY)
+            return null     // memory mapped arrays can never have an initializer value other than the address where they're mapped.
+
+        // convert the initializer range expression from a range or int, to an actual array.
+        when(decl.datatype) {
+            DataType.ARRAY_UB, DataType.ARRAY_B, DataType.ARRAY_UW, DataType.ARRAY_W, DataType.ARRAY_W_SPLIT, DataType.ARRAY_UW_SPLIT -> {
+                val rangeExpr = decl.value as? RangeExpression
+                if(rangeExpr!=null) {
+                    val constRange = rangeExpr.toConstantIntegerRange()
+                    if(constRange?.isEmpty()==true) {
+                        if(constRange.first>constRange.last && constRange.step>=0)
+                            errors.err("descending range with positive step", decl.value?.position!!)
+                        else if(constRange.first<constRange.last && constRange.step<=0)
+                            errors.err("ascending range with negative step", decl.value?.position!!)
+                    }
+                    val declArraySize = decl.arraysize?.constIndex()
+                    if(declArraySize!=null && declArraySize!=rangeExpr.size())
+                        errors.err("range expression size (${rangeExpr.size()}) doesn't match declared array size ($declArraySize)", decl.value?.position!!)
+                    if(constRange!=null) {
+                        val eltType = rangeExpr.inferType(program).getOr(DataType.UBYTE)
+                        return if(eltType in ByteDatatypes) {
+                            ArrayLiteral(InferredTypes.InferredType.known(decl.datatype),
+                                constRange.map { NumericLiteral(eltType, it.toDouble(), decl.value!!.position) }.toTypedArray(),
+                                position = decl.value!!.position)
+                        } else {
+                            ArrayLiteral(InferredTypes.InferredType.known(decl.datatype),
+                                constRange.map { NumericLiteral(eltType, it.toDouble(), decl.value!!.position) }.toTypedArray(),
+                                position = decl.value!!.position)
+                        }
+                    }
+                }
+                val numericLv = decl.value as? NumericLiteral
+                if(numericLv!=null && numericLv.type== DataType.FLOAT)
+                    errors.err("arraysize requires only integers here", numericLv.position)
+                val size = decl.arraysize?.constIndex() ?: return null
+                if (rangeExpr==null && numericLv!=null) {
+                    // arraysize initializer is empty or a single int, and we know the size; create the arraysize.
+                    val fillvalue = numericLv.number.toInt()
+                    when(decl.datatype){
+                        DataType.ARRAY_UB -> {
+                            if(fillvalue !in 0..255)
+                                errors.err("ubyte value overflow", numericLv.position)
+                        }
+                        DataType.ARRAY_B -> {
+                            if(fillvalue !in -128..127)
+                                errors.err("byte value overflow", numericLv.position)
+                        }
+                        DataType.ARRAY_UW -> {
+                            if(fillvalue !in 0..65535)
+                                errors.err("uword value overflow", numericLv.position)
+                        }
+                        DataType.ARRAY_W -> {
+                            if(fillvalue !in -32768..32767)
+                                errors.err("word value overflow", numericLv.position)
+                        }
+                        else -> {}
+                    }
+                    // create the array itself, filled with the fillvalue.
+                    val array = Array(size) {fillvalue}.map { NumericLiteral(ArrayToElementTypes.getValue(decl.datatype), it.toDouble(), numericLv.position) }.toTypedArray<Expression>()
+                    return ArrayLiteral(InferredTypes.InferredType.known(decl.datatype), array, position = numericLv.position)
+                }
+            }
+            DataType.ARRAY_F -> {
+                val rangeExpr = decl.value as? RangeExpression
+                if(rangeExpr!=null) {
+                    // convert the initializer range expression to an actual array of floats
+                    val declArraySize = decl.arraysize?.constIndex()
+                    if(declArraySize!=null && declArraySize!=rangeExpr.size())
+                        errors.err("range expression size (${rangeExpr.size()}) doesn't match declared array size ($declArraySize)", decl.value?.position!!)
+                    val constRange = rangeExpr.toConstantIntegerRange()
+                    if(constRange!=null) {
+                        return ArrayLiteral(InferredTypes.InferredType.known(DataType.ARRAY_F),
+                            constRange.map { NumericLiteral(DataType.FLOAT, it.toDouble(), decl.value!!.position) }.toTypedArray(),
+                            position = decl.value!!.position)
+                    }
+                }
+
+                val numericLv = decl.value as? NumericLiteral
+                val size = decl.arraysize?.constIndex() ?: return null
+                if(rangeExpr==null && numericLv!=null) {
+                    // arraysize initializer is a single int, and we know the size.
+                    val fillvalue = numericLv.number
+                    if (fillvalue < compTarget.machine.FLOAT_MAX_NEGATIVE || fillvalue > compTarget.machine.FLOAT_MAX_POSITIVE)
+                        errors.err("float value overflow", numericLv.position)
+                    else {
+                        // create the array itself, filled with the fillvalue.
+                        val array = Array(size) {fillvalue}.map { NumericLiteral(DataType.FLOAT, it, numericLv.position) }.toTypedArray<Expression>()
+                        return ArrayLiteral(InferredTypes.InferredType.known(DataType.ARRAY_F), array, position = numericLv.position)
+                    }
+                }
+            }
+            DataType.ARRAY_BOOL -> {
+                val numericLv = decl.value as? NumericLiteral
+                val size = decl.arraysize?.constIndex() ?: return null
+                if(numericLv!=null) {
+                    // arraysize initializer is a single int, and we know the size.
+                    val fillvalue = if(numericLv.number==0.0) 0.0 else 1.0
+                    val array = Array(size) {fillvalue}.map { NumericLiteral(DataType.UBYTE, fillvalue, numericLv.position) }.toTypedArray<Expression>()
+                    return ArrayLiteral(InferredTypes.InferredType.known(DataType.ARRAY_BOOL), array, position = numericLv.position)
+                }
+            }
+            else -> return null
+        }
+        return null
+    }
 }

codeOptimizers/src/prog8/optimizer/ExpressionSimplifier.kt

@@ -13,7 +13,6 @@ import prog8.ast.statements.Jump
 import prog8.ast.walk.AstWalker
 import prog8.ast.walk.IAstModification
 import prog8.code.core.*
-import prog8.code.target.VMTarget
 import kotlin.math.abs
 import kotlin.math.log2
 import kotlin.math.pow
@@ -33,8 +32,8 @@ class ExpressionSimplifier(private val program: Program,
         val literal = typecast.expression as? NumericLiteral
         if (literal != null) {
             val newLiteral = literal.cast(typecast.type)
-            if (newLiteral.isValid && newLiteral.valueOrZero() !== literal) {
-                mods += IAstModification.ReplaceNode(typecast, newLiteral.valueOrZero(), parent)
+            if (newLiteral.isValid && newLiteral.value!! !== literal) {
+                mods += IAstModification.ReplaceNode(typecast, newLiteral.value!!, parent)
             }
         }
 
@@ -66,30 +65,36 @@ class ExpressionSimplifier(private val program: Program,
                 )
             }
             if(elsepart.statements.singleOrNull() is Jump) {
-                val invertedCondition = invertCondition(ifElse.condition)
-                if(invertedCondition!=null) {
-                    return listOf(
-                        IAstModification.ReplaceNode(ifElse.condition, invertedCondition, ifElse),
-                        IAstModification.InsertAfter(ifElse, truepart, parent as IStatementContainer),
-                        IAstModification.ReplaceNode(elsepart, AnonymousScope(mutableListOf(), elsepart.position), ifElse),
-                        IAstModification.ReplaceNode(truepart, elsepart, ifElse)
-                    )
-                }
+                val invertedCondition = invertCondition(ifElse.condition, program)
+                return listOf(
+                    IAstModification.ReplaceNode(ifElse.condition, invertedCondition, ifElse),
+                    IAstModification.InsertAfter(ifElse, truepart, parent as IStatementContainer),
+                    IAstModification.ReplaceNode(elsepart, AnonymousScope(mutableListOf(), elsepart.position), ifElse),
+                    IAstModification.ReplaceNode(truepart, elsepart, ifElse)
+                )
             }
         }
 
-        if(compTarget.name!=VMTarget.NAME) {
-            val booleanCondition = ifElse.condition as? BinaryExpression
-            if(booleanCondition!=null && booleanCondition.operator=="&") {
-                // special optimization of WORD & $ff00  ->  just and the msb of WORD with $ff
-                val rightNum = booleanCondition.right as? NumericLiteral
-                if(rightNum!=null && rightNum.type==DataType.UWORD && (rightNum.number.toInt() and 0x00ff)==0) {
+        val booleanCondition = ifElse.condition as? BinaryExpression
+        if(booleanCondition!=null && booleanCondition.operator=="&") {
+            val rightNum = booleanCondition.right as? NumericLiteral
+            if (rightNum!=null && rightNum.type==DataType.UWORD) {
+                if ((rightNum.number.toInt() and 0x00ff) == 0) {
+                    // if WORD & $xx00  ->  if msb(WORD) & $xx
                     val msb = BuiltinFunctionCall(IdentifierReference(listOf("msb"), booleanCondition.left.position), mutableListOf(booleanCondition.left), booleanCondition.left.position)
                     val bytevalue = NumericLiteral(DataType.UBYTE, (rightNum.number.toInt() shr 8).toDouble(), booleanCondition.right.position)
                     return listOf(
                         IAstModification.ReplaceNode(booleanCondition.left, msb, booleanCondition),
                         IAstModification.ReplaceNode(booleanCondition.right, bytevalue, booleanCondition))
                 }
+                else if ((rightNum.number.toInt() and 0xff00) == 0) {
+                    // if WORD & $00ff  ->  if lsb(WORD) & $ff
+                    val lsb = BuiltinFunctionCall(IdentifierReference(listOf("lsb"), booleanCondition.left.position), mutableListOf(booleanCondition.left), booleanCondition.left.position)
+                    val bytevalue = NumericLiteral(DataType.UBYTE, rightNum.number, booleanCondition.right.position)
+                    return listOf(
+                        IAstModification.ReplaceNode(booleanCondition.left, lsb, booleanCondition),
+                        IAstModification.ReplaceNode(booleanCondition.right, bytevalue, booleanCondition))
+                }
             }
         }
 
@@ -97,6 +102,10 @@ class ExpressionSimplifier(private val program: Program,
     }
 
     override fun after(expr: BinaryExpression, parent: Node): Iterable<IAstModification> {
+        val newExpr = applyAbsorptionLaws(expr)
+        if(newExpr!=null)
+            return listOf(IAstModification.ReplaceNode(expr, newExpr, parent))
+
         val leftVal = expr.left.constValue(program)
         val rightVal = expr.right.constValue(program)
 
@@ -158,8 +167,8 @@ class ExpressionSimplifier(private val program: Program,
                     val y = determineY(x, leftBinExpr)
                     if (y != null) {
                         val yPlus1 = BinaryExpression(y, "+", NumericLiteral(leftDt, 1.0, y.position), y.position)
-                        val newExpr = BinaryExpression(x, "*", yPlus1, x.position)
-                        return listOf(IAstModification.ReplaceNode(expr, newExpr, parent))
+                        val replacement = BinaryExpression(x, "*", yPlus1, x.position)
+                        return listOf(IAstModification.ReplaceNode(expr, replacement, parent))
                     }
                 } else {
                     // Y*X - X  ->  X*(Y - 1)
@@ -168,8 +177,8 @@ class ExpressionSimplifier(private val program: Program,
                     val y = determineY(x, leftBinExpr)
                     if (y != null) {
                         val yMinus1 = BinaryExpression(y, "-", NumericLiteral(leftDt, 1.0, y.position), y.position)
-                        val newExpr = BinaryExpression(x, "*", yMinus1, x.position)
-                        return listOf(IAstModification.ReplaceNode(expr, newExpr, parent))
+                        val replacement = BinaryExpression(x, "*", yMinus1, x.position)
+                        return listOf(IAstModification.ReplaceNode(expr, replacement, parent))
                     }
                 }
             } else if (rightBinExpr?.operator == "*") {
@@ -180,8 +189,8 @@ class ExpressionSimplifier(private val program: Program,
                     val y = determineY(x, rightBinExpr)
                     if (y != null) {
                         val yPlus1 = BinaryExpression(y, "+", NumericLiteral.optimalInteger(1, y.position), y.position)
-                        val newExpr = BinaryExpression(x, "*", yPlus1, x.position)
-                        return listOf(IAstModification.ReplaceNode(expr, newExpr, parent))
+                        val replacement = BinaryExpression(x, "*", yPlus1, x.position)
+                        return listOf(IAstModification.ReplaceNode(expr, replacement, parent))
                     }
                 }
             }
@@ -270,7 +279,7 @@ class ExpressionSimplifier(private val program: Program,
 
         // simplify when a term is constant and directly determines the outcome
         val constFalse = NumericLiteral.fromBoolean(false, expr.position)
-        val newExpr: Expression? = when (expr.operator) {
+        val newExpr2 = when (expr.operator) {
             "|" -> {
                 when {
                     leftVal?.number==0.0 -> expr.right
@@ -315,33 +324,102 @@ class ExpressionSimplifier(private val program: Program,
         }
 
         if(rightVal!=null && leftDt==DataType.BOOL) {
-            // see if we can replace comparison against true/1 with simpler comparison against zero
-            if (expr.operator == "==") {
-                if (rightVal.number == 1.0) {
-                    val zero = NumericLiteral(DataType.UBYTE, 0.0, expr.right.position)
-                    return listOf(
-                        IAstModification.SetExpression({expr.operator="!="}, expr, parent),
-                        IAstModification.ReplaceNode(expr.right, zero, expr)
-                    )
-                }
-            }
-            if (expr.operator == "!=") {
-                if (rightVal.number == 1.0) {
-                    val zero = NumericLiteral(DataType.UBYTE, 0.0, expr.right.position)
-                    return listOf(
-                        IAstModification.SetExpression({expr.operator="=="}, expr, parent),
-                        IAstModification.ReplaceNode(expr.right, zero, expr)
-                    )
+            // boolean compare against a number -> just keep the boolean, no compare
+            if(expr.operator=="==" || expr.operator=="!=") {
+                val test = if (expr.operator == "==") rightVal.asBooleanValue else !rightVal.asBooleanValue
+                return if (test) {
+                    listOf(IAstModification.ReplaceNode(expr, expr.left, parent))
+                } else {
+                    listOf(IAstModification.ReplaceNode(expr, invertCondition(expr.left, program), parent))
                 }
             }
         }
 
-        if(newExpr != null)
-            return listOf(IAstModification.ReplaceNode(expr, newExpr, parent))
+        if(newExpr2 != null)
+            return listOf(IAstModification.ReplaceNode(expr, newExpr2, parent))
+
+        if (rightVal!=null && (expr.operator == "==" || expr.operator == "!=")) {
+            val bitwise = expr.left as? BinaryExpression
+            if(bitwise!=null && bitwise.operator=="&" && bitwise.inferType(program).isWords) {
+                val andNum = (bitwise.right as? NumericLiteral)?.number?.toInt()
+                if (andNum!=null) {
+                    if ((andNum and 0x00ff) == 0) {
+                        // (WORD & $xx00)==y  ->  (msb(WORD) & $xx)==y
+                        val msb = BuiltinFunctionCall(IdentifierReference(listOf("msb"), bitwise.left.position), mutableListOf(bitwise.left), bitwise.left.position)
+                        val bytevalue = NumericLiteral(DataType.UBYTE, (andNum shr 8).toDouble(), bitwise.right.position)
+                        val rightvalByte = NumericLiteral(DataType.UBYTE, (rightVal.number.toInt() shr 8).toDouble(), rightVal.position)
+                        return listOf(
+                            IAstModification.ReplaceNode(bitwise.left, msb, bitwise),
+                            IAstModification.ReplaceNode(bitwise.right, bytevalue, bitwise),
+                            IAstModification.ReplaceNode(expr.right, rightvalByte, expr)
+                        )
+                    }
+                    else if((andNum and 0xff00) == 0) {
+                        // (WORD & $00xx)==y  ->  (lsb(WORD) & $xx)==y
+                        val lsb = BuiltinFunctionCall(IdentifierReference(listOf("lsb"), bitwise.left.position), mutableListOf(bitwise.left), bitwise.left.position)
+                        val bytevalue = NumericLiteral(DataType.UBYTE, andNum.toDouble(), bitwise.right.position)
+                        val rightvalByte = NumericLiteral(DataType.UBYTE, (rightVal.number.toInt() and 255).toDouble(), rightVal.position)
+                        return listOf(
+                            IAstModification.ReplaceNode(bitwise.left, lsb, bitwise),
+                            IAstModification.ReplaceNode(bitwise.right, bytevalue, bitwise),
+                            IAstModification.ReplaceNode(expr.right, rightvalByte, expr)
+                        )
+                    }
+                }
+            }
+        }
 
         return noModifications
     }
 
+    override fun after(expr: PrefixExpression, parent: Node): Iterable<IAstModification> {
+        if(expr.operator=="not") {
+            // not  X <compare> Y  ->   X <invertedcompare> Y
+            val binExpr = expr.expression as? BinaryExpression
+            if(binExpr!=null) {
+                val invertedOperator = invertedComparisonOperator(binExpr.operator)
+                if(invertedOperator!=null) {
+                    val inverted = BinaryExpression(binExpr.left, invertedOperator, binExpr.right, binExpr.position)
+                    return listOf(IAstModification.ReplaceNode(expr, inverted, parent))
+                }
+            }
+        }
+        return noModifications
+    }
+
+
+    private fun applyAbsorptionLaws(expr: BinaryExpression): Expression? {
+        val rightB = expr.right as? BinaryExpression
+        if(rightB!=null) {
+            // absorption laws:  a or (a and b) --> a,  a and (a or b) --> a
+            if(expr.operator=="or" && rightB.operator=="and") {
+                if(expr.left isSameAs rightB.left || expr.left isSameAs rightB.right) {
+                    return expr.left
+                }
+            }
+            else if(expr.operator=="and" && rightB.operator=="or") {
+                if(expr.left isSameAs rightB.left || expr.left isSameAs rightB.right) {
+                    return expr.left
+                }
+            }
+        }
+        val leftB = expr.left as? BinaryExpression
+        if(leftB!=null) {
+            // absorption laws:  (a and b) or a --> a,  (a or b) and a --> a
+            if(expr.operator=="or" && leftB.operator=="and") {
+                if(expr.right isSameAs leftB.left || expr.left isSameAs leftB.right) {
+                    return expr.right
+                }
+            }
+            else if(expr.operator=="and" && leftB.operator=="or") {
+                if(expr.right isSameAs leftB.left || expr.right isSameAs leftB.right) {
+                    return expr.right
+                }
+            }
+        }
+        return null
+    }
+
     override fun after(functionCallExpr: FunctionCallExpression, parent: Node): Iterable<IAstModification> {
         if(functionCallExpr.target.nameInSource == listOf("lsb")) {
             if(functionCallExpr.args.isEmpty())
@@ -349,10 +427,15 @@ class ExpressionSimplifier(private val program: Program,
             val arg = functionCallExpr.args[0]
             if(arg is TypecastExpression) {
                 val valueDt = arg.expression.inferType(program)
-                if (valueDt istype DataType.BYTE || valueDt istype DataType.UBYTE) {
-                    // useless lsb() of byte value that was typecasted to word
+                if (valueDt istype DataType.UBYTE) {
+                    // useless lsb() of ubyte value
                     return listOf(IAstModification.ReplaceNode(functionCallExpr, arg.expression, parent))
                 }
+                else if (valueDt istype DataType.BYTE) {
+                    // useless lsb() of byte value, but as lsb() returns unsigned, we have to cast now.
+                    val cast = TypecastExpression(arg.expression, DataType.UBYTE, true, arg.position)
+                    return listOf(IAstModification.ReplaceNode(functionCallExpr, cast, parent))
+                }
             } else {
                 if(arg is IdentifierReference && arg.nameInSource.size==2
                     && arg.nameInSource[0]=="cx16" && arg.nameInSource[1].uppercase() in RegisterOrPair.names) {
@@ -361,10 +444,15 @@ class ExpressionSimplifier(private val program: Program,
                     return listOf(IAstModification.ReplaceNode(functionCallExpr, highReg, parent))
                 }
                 val argDt = arg.inferType(program)
-                if (argDt istype DataType.BYTE || argDt istype DataType.UBYTE) {
+                if (argDt istype DataType.UBYTE) {
                     // useless lsb() of byte value
                     return listOf(IAstModification.ReplaceNode(functionCallExpr, arg, parent))
                 }
+                else if (argDt istype DataType.BYTE) {
+                    // useless lsb() of byte value, but as lsb() returns unsigned, we have to cast now.
+                    val cast = TypecastExpression(arg, DataType.UBYTE, true, arg.position)
+                    return listOf(IAstModification.ReplaceNode(functionCallExpr, cast, parent))
+                }
             }
         }
         else if(functionCallExpr.target.nameInSource == listOf("msb")) {
@@ -405,6 +493,14 @@ class ExpressionSimplifier(private val program: Program,
                 return listOf(IAstModification.ReplaceNode(functionCallExpr, cast, parent))
             }
         }
+        else if(functionCallExpr.target.nameInSource == listOf("string", "contains")) {
+            val target = (functionCallExpr.args[0] as? IdentifierReference)?.targetVarDecl(program)
+            if(target?.value is StringLiteral) {
+                errors.info("for actual strings, use a regular containment check instead: 'char in string'", functionCallExpr.position)
+                val contains = ContainmentCheck(functionCallExpr.args[1], functionCallExpr.args[0], functionCallExpr.position)
+                return listOf(IAstModification.ReplaceNode(functionCallExpr as Node, contains, parent))
+            }
+        }
 
         return noModifications
     }
@@ -540,10 +636,25 @@ class ExpressionSimplifier(private val program: Program,
                         return expr.left
                     }
                 }
+                256.0 -> {
+                    when(leftDt) {
+                        DataType.UBYTE -> return NumericLiteral(DataType.UBYTE, 0.0, expr.position)
+                        DataType.BYTE -> return null        // is either 0 or -1 we cannot tell here
+                        DataType.UWORD, DataType.WORD -> {
+                            // just use:  msb(value) as type
+                            val msb = BuiltinFunctionCall(IdentifierReference(listOf("msb"), expr.position), mutableListOf(expr.left), expr.position)
+                            return if(leftDt==DataType.WORD)
+                                TypecastExpression(msb, DataType.BYTE, true, expr.position)
+                            else
+                                TypecastExpression(msb, DataType.UWORD, true, expr.position)
+                        }
+                        else -> return null
+                    }
+                }
                 in powersOfTwo -> {
                     if (leftDt==DataType.UBYTE || leftDt==DataType.UWORD) {
                         // Unsigned number divided by a power of two => shift right
-                        // Signed number can't simply be bitshifted in this case (due to rounding issues for negative values),
+                        // Signed number can't simply be bitshifted in this case (due to rounding issues for negative values),  TODO is this correct???
                         // so we leave that as is and let the code generator deal with it.
                         val numshifts = log2(cv).toInt()
                         return BinaryExpression(expr.left, ">>", NumericLiteral.optimalInteger(numshifts, expr.position), expr.position)
@@ -705,8 +816,8 @@ class ExpressionSimplifier(private val program: Program,
             }
             DataType.UWORD -> {
                 if (amount >= 16) {
-                    errors.warn("shift always results in 0", expr.position)
-                    return NumericLiteral.optimalInteger(0, expr.position)
+                    errors.err("useless to shift by more than 15 bits", expr.position)
+                    return null
                 }
                 else if(amount==8) {
                     // shift right by 8 bits is just a byte operation: msb(X) as uword
@@ -720,11 +831,21 @@ class ExpressionSimplifier(private val program: Program,
                 }
             }
             DataType.WORD -> {
-                // bit-shifting a signed value shouldn't be allowed by the compiler but here we go...
-                if (amount > 16) {
-                    expr.right = NumericLiteral.optimalInteger(16, expr.right.position)
+                if (amount >= 16) {
+                    errors.err("useless to shift by more than 15 bits", expr.position)
                     return null
                 }
+                else if(amount == 8) {
+                    // shift right by 8 bits is just a byte operation: msb(X) as byte  (will get converted to word later)
+                    val msb = FunctionCallExpression(IdentifierReference(listOf("msb"), expr.position), mutableListOf(expr.left), expr.position)
+                    return TypecastExpression(msb, DataType.BYTE, true, expr.position)
+                }
+                else if(amount > 8) {
+                    // same as above but with residual shifts. Take care to do signed shift.
+                    val msb = FunctionCallExpression(IdentifierReference(listOf("msb"), expr.position), mutableListOf(expr.left), expr.position)
+                    val signed = TypecastExpression(msb, DataType.BYTE, true, expr.position)
+                    return BinaryExpression(signed, ">>", NumericLiteral.optimalInteger(amount - 8, expr.position), expr.position)
+                }
             }
             else -> {
             }

codeOptimizers/src/prog8/optimizer/Extensions.kt

@@ -7,13 +7,13 @@ import prog8.code.core.ICompilationTarget
 import prog8.code.core.IErrorReporter
 
 
-fun Program.constantFold(errors: IErrorReporter, compTarget: ICompilationTarget) {
-    val valuetypefixer = VarConstantValueTypeAdjuster(this, errors)
+fun Program.constantFold(errors: IErrorReporter, options: CompilationOptions) {
+    val valuetypefixer = VarConstantValueTypeAdjuster(this, options, errors)
     valuetypefixer.visit(this)
     if(errors.noErrors()) {
         valuetypefixer.applyModifications()
 
-        val replacer = ConstantIdentifierReplacer(this, errors, compTarget)
+        val replacer = ConstantIdentifierReplacer(this, errors, options.compTarget)
         replacer.visit(this)
         if (errors.noErrors()) {
             replacer.applyModifications()
@@ -22,7 +22,7 @@ fun Program.constantFold(errors: IErrorReporter, compTarget: ICompilationTarget)
             if(errors.noErrors()) {
                 valuetypefixer.applyModifications()
 
-                val optimizer = ConstantFoldingOptimizer(this)
+                val optimizer = ConstantFoldingOptimizer(this, errors)
                 optimizer.visit(this)
                 while (errors.noErrors() && optimizer.applyModifications() > 0) {
                     optimizer.visit(this)
@@ -65,9 +65,3 @@ fun Program.simplifyExpressions(errors: IErrorReporter, target: ICompilationTarg
     opti.visit(this)
     return opti.applyModifications()
 }
-
-fun Program.splitBinaryExpressions(options: CompilationOptions) : Int {
-    val opti = BinExprSplitter(this, options)
-    opti.visit(this)
-    return opti.applyModifications()
-}

codeOptimizers/src/prog8/optimizer/Inliner.kt

@@ -34,85 +34,100 @@ class Inliner(private val program: Program, private val options: CompilationOpti
                 val containsSubsOrVariables = subroutine.statements.any { it is VarDecl || it is Subroutine}
                 if(!containsSubsOrVariables) {
                     if(subroutine.statements.size==1 || (subroutine.statements.size==2 && isEmptyReturn(subroutine.statements[1]))) {
-                        // subroutine is possible candidate to be inlined
-                        subroutine.inline =
-                            when(val stmt=subroutine.statements[0]) {
-                                is Return -> {
-                                    if(stmt.value is NumericLiteral)
-                                        true
-                                    else if(stmt.value==null)
-                                        true
-                                    else if (stmt.value is IdentifierReference) {
-                                        makeFullyScoped(stmt.value as IdentifierReference)
-                                        true
-                                    } else if(stmt.value!! is IFunctionCall && (stmt.value as IFunctionCall).args.size<=1 && (stmt.value as IFunctionCall).args.all { it is NumericLiteral || it is IdentifierReference }) {
-                                        when (stmt.value) {
-                                            is BuiltinFunctionCall -> {
-                                                makeFullyScoped(stmt.value as BuiltinFunctionCall)
-                                                true
+                        if(subroutine !== program.entrypoint) {
+                            // subroutine is possible candidate to be inlined
+                            subroutine.inline =
+                                when (val stmt = subroutine.statements[0]) {
+                                    is Return -> {
+                                        if (stmt.value is NumericLiteral)
+                                            true
+                                        else if (stmt.value == null)
+                                            true
+                                        else if (stmt.value is IdentifierReference) {
+                                            makeFullyScoped(stmt.value as IdentifierReference)
+                                            true
+                                        } else if (stmt.value!! is IFunctionCall && (stmt.value as IFunctionCall).args.size <= 1 && (stmt.value as IFunctionCall).args.all { it is NumericLiteral || it is IdentifierReference }) {
+                                            when (stmt.value) {
+                                                is BuiltinFunctionCall -> {
+                                                    makeFullyScoped(stmt.value as BuiltinFunctionCall)
+                                                    true
+                                                }
+
+                                                is FunctionCallExpression -> {
+                                                    makeFullyScoped(stmt.value as FunctionCallExpression)
+                                                    true
+                                                }
+
+                                                else -> false
                                             }
-                                            is FunctionCallExpression -> {
-                                                makeFullyScoped(stmt.value as FunctionCallExpression)
-                                                true
-                                            }
-                                            else -> false
-                                        }
-                                    } else
-                                        false
-                                }
-                                is Assignment -> {
-                                    if(stmt.value.isSimple) {
-                                        val targetInline =
-                                            if(stmt.target.identifier!=null) {
-                                                makeFullyScoped(stmt.target.identifier!!)
-                                                true
-                                            } else if(stmt.target.memoryAddress?.addressExpression is NumericLiteral || stmt.target.memoryAddress?.addressExpression is IdentifierReference) {
-                                                if(stmt.target.memoryAddress?.addressExpression is IdentifierReference)
-                                                    makeFullyScoped(stmt.target.memoryAddress?.addressExpression as IdentifierReference)
-                                                true
-                                            } else
-                                                false
-                                        val valueInline =
-                                            if(stmt.value is IdentifierReference) {
-                                                makeFullyScoped(stmt.value as IdentifierReference)
-                                                true
-                                            } else if((stmt.value as? DirectMemoryRead)?.addressExpression is NumericLiteral || (stmt.value as? DirectMemoryRead)?.addressExpression is IdentifierReference) {
-                                                if((stmt.value as? DirectMemoryRead)?.addressExpression is IdentifierReference)
-                                                    makeFullyScoped((stmt.value as? DirectMemoryRead)?.addressExpression as IdentifierReference)
-                                                true
-                                            } else
-                                                false
-                                        targetInline || valueInline
-                                    } else
-                                        false
-                                }
-                                is BuiltinFunctionCallStatement -> {
-                                    val inline = stmt.args.size<=1 && stmt.args.all { it is NumericLiteral || it is IdentifierReference }
-                                    if(inline)
-                                        makeFullyScoped(stmt)
-                                    inline
-                                }
-                                is FunctionCallStatement -> {
-                                    val inline = stmt.args.size<=1 && stmt.args.all { it is NumericLiteral || it is IdentifierReference }
-                                    if(inline)
-                                        makeFullyScoped(stmt)
-                                    inline
-                                }
-                                is PostIncrDecr -> {
-                                    if(stmt.target.identifier!=null) {
-                                        makeFullyScoped(stmt.target.identifier!!)
-                                        true
+                                        } else
+                                            false
                                     }
-                                    else if(stmt.target.memoryAddress?.addressExpression is NumericLiteral || stmt.target.memoryAddress?.addressExpression is IdentifierReference) {
-                                        if(stmt.target.memoryAddress?.addressExpression is IdentifierReference)
-                                            makeFullyScoped(stmt.target.memoryAddress?.addressExpression as IdentifierReference)
-                                        true
-                                    } else
-                                        false
+
+                                    is Assignment -> {
+                                        if (stmt.value.isSimple) {
+                                            val targetInline =
+                                                if (stmt.target.identifier != null) {
+                                                    makeFullyScoped(stmt.target.identifier!!)
+                                                    true
+                                                } else if (stmt.target.memoryAddress?.addressExpression is NumericLiteral || stmt.target.memoryAddress?.addressExpression is IdentifierReference) {
+                                                    if (stmt.target.memoryAddress?.addressExpression is IdentifierReference)
+                                                        makeFullyScoped(stmt.target.memoryAddress?.addressExpression as IdentifierReference)
+                                                    true
+                                                } else
+                                                    false
+                                            val valueInline =
+                                                if (stmt.value is IdentifierReference) {
+                                                    makeFullyScoped(stmt.value as IdentifierReference)
+                                                    true
+                                                } else if ((stmt.value as? DirectMemoryRead)?.addressExpression is NumericLiteral || (stmt.value as? DirectMemoryRead)?.addressExpression is IdentifierReference) {
+                                                    if ((stmt.value as? DirectMemoryRead)?.addressExpression is IdentifierReference)
+                                                        makeFullyScoped((stmt.value as? DirectMemoryRead)?.addressExpression as IdentifierReference)
+                                                    true
+                                                } else
+                                                    false
+                                            targetInline || valueInline
+                                        } else
+                                            false
+                                    }
+
+                                    is BuiltinFunctionCallStatement -> {
+                                        val inline =
+                                            stmt.args.size <= 1 && stmt.args.all { it is NumericLiteral || it is IdentifierReference }
+                                        if (inline)
+                                            makeFullyScoped(stmt)
+                                        inline
+                                    }
+
+                                    is FunctionCallStatement -> {
+                                        val inline =
+                                            stmt.args.size <= 1 && stmt.args.all { it is NumericLiteral || it is IdentifierReference }
+                                        if (inline)
+                                            makeFullyScoped(stmt)
+                                        inline
+                                    }
+
+                                    is PostIncrDecr -> {
+                                        if (stmt.target.identifier != null) {
+                                            makeFullyScoped(stmt.target.identifier!!)
+                                            true
+                                        } else if (stmt.target.memoryAddress?.addressExpression is NumericLiteral || stmt.target.memoryAddress?.addressExpression is IdentifierReference) {
+                                            if (stmt.target.memoryAddress?.addressExpression is IdentifierReference)
+                                                makeFullyScoped(stmt.target.memoryAddress?.addressExpression as IdentifierReference)
+                                            true
+                                        } else
+                                            false
+                                    }
+
+                                    is Jump -> true
+                                    else -> false
                                 }
-                                is Jump -> true
-                                else -> false
-                            }
+                        }
+                    }
+
+                    if(subroutine.inline && subroutine.statements.size>1) {
+                        require(subroutine.statements.size==2 && isEmptyReturn(subroutine.statements[1]))
+                        subroutine.statements.removeLast()      // get rid of the Return, to be able to inline the (single) statement preceding it.
                     }
                 }
             }
@@ -129,16 +144,20 @@ class Inliner(private val program: Program, private val options: CompilationOpti
 
         private fun makeFullyScoped(call: BuiltinFunctionCallStatement) {
             val scopedArgs = makeScopedArgs(call.args)
-            val scopedCall = BuiltinFunctionCallStatement(call.target.copy(), scopedArgs.toMutableList(), call.position)
-            modifications += IAstModification.ReplaceNode(call, scopedCall, call.parent)
+            if(scopedArgs.any()) {
+                val scopedCall = BuiltinFunctionCallStatement(call.target.copy(), scopedArgs.toMutableList(), call.position)
+                modifications += IAstModification.ReplaceNode(call, scopedCall, call.parent)
+            }
         }
 
         private fun makeFullyScoped(call: FunctionCallStatement) {
             call.target.targetSubroutine(program)?.let { sub ->
                 val scopedName = IdentifierReference(sub.scopedName, call.target.position)
                 val scopedArgs = makeScopedArgs(call.args)
-                val scopedCall = FunctionCallStatement(scopedName, scopedArgs.toMutableList(), call.void, call.position)
-                modifications += IAstModification.ReplaceNode(call, scopedCall, call.parent)
+                if(scopedArgs.any()) {
+                    val scopedCall = FunctionCallStatement(scopedName, scopedArgs.toMutableList(), call.void, call.position)
+                    modifications += IAstModification.ReplaceNode(call, scopedCall, call.parent)
+                }
             }
         }
 
@@ -146,8 +165,10 @@ class Inliner(private val program: Program, private val options: CompilationOpti
             call.target.targetSubroutine(program)?.let { sub ->
                 val scopedName = IdentifierReference(sub.scopedName, call.target.position)
                 val scopedArgs = makeScopedArgs(call.args)
-                val scopedCall = BuiltinFunctionCall(scopedName, scopedArgs.toMutableList(), call.position)
-                modifications += IAstModification.ReplaceNode(call, scopedCall, call.parent)
+                if(scopedArgs.any()) {
+                    val scopedCall = BuiltinFunctionCall(scopedName, scopedArgs.toMutableList(), call.position)
+                    modifications += IAstModification.ReplaceNode(call, scopedCall, call.parent)
+                }
             }
         }
 
@@ -155,8 +176,10 @@ class Inliner(private val program: Program, private val options: CompilationOpti
             call.target.targetSubroutine(program)?.let { sub ->
                 val scopedName = IdentifierReference(sub.scopedName, call.target.position)
                 val scopedArgs = makeScopedArgs(call.args)
-                val scopedCall = FunctionCallExpression(scopedName, scopedArgs.toMutableList(), call.position)
-                modifications += IAstModification.ReplaceNode(call, scopedCall, call.parent)
+                if(scopedArgs.any()) {
+                    val scopedCall = FunctionCallExpression(scopedName, scopedArgs.toMutableList(), call.position)
+                    modifications += IAstModification.ReplaceNode(call, scopedCall, call.parent)
+                }
             }
         }
 
@@ -165,7 +188,8 @@ class Inliner(private val program: Program, private val options: CompilationOpti
                 when (it) {
                     is NumericLiteral -> it.copy()
                     is IdentifierReference -> {
-                        val scoped = (it.targetStatement(program)!! as INamedStatement).scopedName
+                        val target = it.targetStatement(program) ?: return emptyList()
+                        val scoped = (target as INamedStatement).scopedName
                         IdentifierReference(scoped, it.position)
                     }
                     else -> throw InternalCompilerException("expected only number or identifier arg, otherwise too complex")

codeOptimizers/src/prog8/optimizer/StatementOptimizer.kt

@@ -30,7 +30,7 @@ class StatementOptimizer(private val program: Program,
         if(functionCallStatement.target.nameInSource==listOf("txt", "print")) {
             val arg = functionCallStatement.args.single()
             val stringVar: IdentifierReference? = if(arg is AddressOf) {
-                arg.identifier
+                if(arg.arrayIndex==null) arg.identifier else null
             } else {
                 arg as? IdentifierReference
             }
@@ -45,11 +45,7 @@ class StatementOptimizer(private val program: Program,
                             mutableListOf(NumericLiteral(DataType.UBYTE, firstCharEncoded.toDouble(), pos)),
                             functionCallStatement.void, pos
                         )
-                        val stringDecl = string.parent as VarDecl
-                        return listOf(
-                            IAstModification.ReplaceNode(functionCallStatement, chrout, parent),
-                            IAstModification.Remove(stringDecl, stringDecl.parent as IStatementContainer)
-                        )
+                        return listOf(IAstModification.ReplaceNode(functionCallStatement, chrout, parent))
                     } else if (string.value.length == 2) {
                         val firstTwoCharsEncoded = options.compTarget.encodeString(string.value.take(2), string.encoding)
                         val chrout1 = FunctionCallStatement(
@@ -62,11 +58,9 @@ class StatementOptimizer(private val program: Program,
                             mutableListOf(NumericLiteral(DataType.UBYTE, firstTwoCharsEncoded[1].toDouble(), pos)),
                             functionCallStatement.void, pos
                         )
-                        val stringDecl = string.parent as VarDecl
                         return listOf(
                             IAstModification.InsertBefore(functionCallStatement, chrout1, parent as IStatementContainer),
-                            IAstModification.ReplaceNode(functionCallStatement, chrout2, parent),
-                            IAstModification.Remove(stringDecl, stringDecl.parent as IStatementContainer)
+                            IAstModification.ReplaceNode(functionCallStatement, chrout2, parent)
                         )
                     }
                 }
@@ -77,6 +71,11 @@ class StatementOptimizer(private val program: Program,
     }
 
     override fun after(ifElse: IfElse, parent: Node): Iterable<IAstModification> {
+        val constvalue = ifElse.condition.constValue(program)
+        if(constvalue!=null) {
+            errors.warn("condition is always ${constvalue.asBooleanValue}", ifElse.condition.position)
+        }
+
         // remove empty if statements
         if(ifElse.truepart.isEmpty() && ifElse.elsepart.isEmpty())
             return listOf(IAstModification.Remove(ifElse, parent as IStatementContainer))
@@ -93,17 +92,12 @@ class StatementOptimizer(private val program: Program,
             )
         }
 
-        val constvalue = ifElse.condition.constValue(program)
         if(constvalue!=null) {
             return if(constvalue.asBooleanValue){
                 // always true -> keep only if-part
-                if(!ifElse.definingModule.isLibrary)
-                    errors.warn("condition is always true", ifElse.condition.position)
                 listOf(IAstModification.ReplaceNode(ifElse, ifElse.truepart, parent))
             } else {
                 // always false -> keep only else-part
-                if(!ifElse.definingModule.isLibrary)
-                    errors.warn("condition is always false", ifElse.condition.position)
                 listOf(IAstModification.ReplaceNode(ifElse, ifElse.elsepart, parent))
             }
         }
@@ -111,19 +105,32 @@ class StatementOptimizer(private val program: Program,
         // remove obvious dangling elses (else after a return)
         if(ifElse.elsepart.isNotEmpty() && ifElse.truepart.statements.singleOrNull() is Return) {
             val elsePart = AnonymousScope(ifElse.elsepart.statements, ifElse.elsepart.position)
-            if(options.slowCodegenWarnings)
-                errors.warn("else can be omitted", ifElse.elsepart.position)
             return listOf(
                 IAstModification.ReplaceNode(ifElse.elsepart, AnonymousScope(mutableListOf(), ifElse.elsepart.position), ifElse),
                 IAstModification.InsertAfter(ifElse, elsePart, parent as IStatementContainer)
             )
         }
+
+        // switch if/else around if the else is just a jump or branch
+        if(ifElse.elsepart.isNotEmpty() && ifElse.elsepart.statements.size==1) {
+            val jump = ifElse.elsepart.statements[0]
+            if(jump is Jump) {
+                val newTruePart = AnonymousScope(mutableListOf(jump), ifElse.elsepart.position)
+                val newElsePart = AnonymousScope(ifElse.truepart.statements, ifElse.truepart.position)
+                return listOf(
+                    IAstModification.ReplaceNode(ifElse.elsepart, newElsePart, ifElse),
+                    IAstModification.ReplaceNode(ifElse.truepart, newTruePart, ifElse),
+                    IAstModification.ReplaceNode(ifElse.condition, invertCondition(ifElse.condition, program), ifElse)
+                )
+            }
+        }
+
         return noModifications
     }
 
     override fun after(forLoop: ForLoop, parent: Node): Iterable<IAstModification> {
         if(forLoop.body.isEmpty()) {
-            errors.warn("removing empty for loop", forLoop.position)
+            errors.info("removing empty for loop", forLoop.position)
             return listOf(IAstModification.Remove(forLoop, parent as IStatementContainer))
         } else if(forLoop.body.statements.size==1) {
             val loopvar = forLoop.body.statements[0] as? VarDecl
@@ -159,7 +166,7 @@ class StatementOptimizer(private val program: Program,
                     return listOf(IAstModification.ReplaceNode(forLoop, scope, parent))
                 }
             }
-            else if(iterable.datatype in ArrayDatatypes) {
+            else if(iterable.isArray) {
                 val size = iterable.arraysize!!.constIndex()
                 if(size==1) {
                     // loop over array of length 1 -> just assign the single value
@@ -176,6 +183,70 @@ class StatementOptimizer(private val program: Program,
             }
         }
 
+        val loopvarDt = forLoop.loopVarDt(program)
+        if(loopvarDt.istype(DataType.UWORD) || loopvarDt.istype(DataType.UBYTE)) {
+            if (range != null && range.from.constValue(program)?.number == 0.0 && range.step.constValue(program)?.number==1.0) {
+                val toBinExpr = range.to as? BinaryExpression
+                if(toBinExpr!=null && toBinExpr.operator=="-" && toBinExpr.right.constValue(program)?.number==1.0) {
+                    // FOR var IN 0 TO X-1 .... ---> var=0, DO {... , var++} UNTIL var==X
+                    val pos = forLoop.position
+                    val condition = BinaryExpression(forLoop.loopVar.copy(), "==", toBinExpr.left, pos)
+                    val incOne = PostIncrDecr(AssignTarget(forLoop.loopVar.copy(), null, null, pos), "++", pos)
+                    forLoop.body.statements.add(incOne)
+                    val replacement = AnonymousScope(mutableListOf(
+                        Assignment(AssignTarget(forLoop.loopVar.copy(), null, null, pos),
+                            NumericLiteral.optimalNumeric(0.0, pos),
+                            AssignmentOrigin.OPTIMIZER, pos),
+                        UntilLoop(forLoop.body, condition, pos)
+                    ), pos)
+                    return listOf(IAstModification.ReplaceNode(forLoop, replacement, parent))
+                }
+
+                if(options.compTarget.name!=VMTarget.NAME) {
+                    // this optimization is not effective for the VM target.
+                    val toConst = range.to.constValue(program)
+                    if (toConst == null) {
+                        // FOR var in 0 TO X ... --->  var=0, REPEAT { ... , IF var==X break , var++ }
+                        val pos = forLoop.position
+                        val incOne = PostIncrDecr(AssignTarget(forLoop.loopVar.copy(), null, null, pos), "++", pos)
+                        val breakCondition = IfElse(
+                            BinaryExpression(forLoop.loopVar, "==", range.to, pos),
+                            AnonymousScope(mutableListOf(Break(pos)), pos),
+                            AnonymousScope(mutableListOf(), pos),
+                            pos
+                        )
+                        forLoop.body.statements.add(breakCondition)
+                        forLoop.body.statements.add(incOne)
+                        val replacement = AnonymousScope(mutableListOf(
+                            Assignment(AssignTarget(forLoop.loopVar.copy(), null, null, pos),
+                                NumericLiteral.optimalNumeric(0.0, pos),
+                                AssignmentOrigin.OPTIMIZER, pos),
+                            RepeatLoop(null, forLoop.body, pos)
+                        ), pos)
+                        return listOf(IAstModification.ReplaceNode(forLoop, replacement, parent))
+                    }
+                }
+            }
+
+            if (range != null && range.to.constValue(program)?.number == 0.0 && range.step.constValue(program)?.number==-1.0) {
+                val fromExpr = range.from
+                if(fromExpr.constValue(program)==null) {
+                    // FOR X = something DOWNTO 0 {...} -->  X=something,  DO { ... , X-- } UNTIL X=255 (or 65535 if uword)
+                    val pos = forLoop.position
+                    val checkValue = NumericLiteral(loopvarDt.getOr(DataType.UNDEFINED), if(loopvarDt.istype(DataType.UBYTE)) 255.0 else 65535.0, pos)
+                    val condition = BinaryExpression(forLoop.loopVar.copy(), "==", checkValue, pos)
+                    val decOne = PostIncrDecr(AssignTarget(forLoop.loopVar.copy(), null, null, pos), "--", pos)
+                    forLoop.body.statements.add(decOne)
+                    val replacement = AnonymousScope(mutableListOf(
+                        Assignment(AssignTarget(forLoop.loopVar.copy(), null, null, pos),
+                            fromExpr, AssignmentOrigin.OPTIMIZER, pos),
+                        UntilLoop(forLoop.body, condition, pos)
+                    ), pos)
+                    return listOf(IAstModification.ReplaceNode(forLoop, replacement, parent))
+                }
+            }
+        }
+
         return noModifications
     }
 
@@ -215,7 +286,7 @@ class StatementOptimizer(private val program: Program,
         val iter = repeatLoop.iterations
         if(iter!=null) {
             if(repeatLoop.body.isEmpty()) {
-                errors.warn("empty loop removed", repeatLoop.position)
+                errors.info("empty loop removed", repeatLoop.position)
                 return listOf(IAstModification.Remove(repeatLoop, parent as IStatementContainer))
             }
             val iterations = iter.constValue(program)?.number?.toInt()
@@ -386,7 +457,8 @@ class StatementOptimizer(private val program: Program,
     }
 
     override fun before(unrollLoop: UnrollLoop, parent: Node): Iterable<IAstModification> {
-        return if(unrollLoop.iterations<1)
+        val iterations = unrollLoop.iterations.constValue(program)?.number?.toInt()
+        return if(iterations!=null && iterations<1)
             listOf(IAstModification.Remove(unrollLoop, parent as IStatementContainer))
         else
             noModifications
@@ -396,14 +468,14 @@ class StatementOptimizer(private val program: Program,
 
         fun replaceWithIf(condition: Expression, trueBlock: AnonymousScope, elseBlock: AnonymousScope?): List<IAstModification> {
             val ifStmt = IfElse(condition, trueBlock, elseBlock ?: AnonymousScope(mutableListOf(), whenStmt.position), whenStmt.position)
-            errors.warn("for boolean condition a normal if statement is preferred", whenStmt.position)
+            errors.info("for boolean condition a normal if statement is preferred", whenStmt.position)
             return listOf(IAstModification.ReplaceNode(whenStmt, ifStmt, parent))
         }
 
         if(whenStmt.condition.inferType(program).isBool) {
             if(whenStmt.choices.all { it.values?.size==1 }) {
                 if (whenStmt.choices.all { it.values!!.single().constValue(program)!!.number in arrayOf(0.0, 1.0) }) {
-                    // it's a when statement on booleans that can just be replaced by an if or if..else.
+                    // it's a when statement on booleans that can just be replaced by an if or if-else.
                     if (whenStmt.choices.size == 1) {
                         return if(whenStmt.choices[0].values!![0].constValue(program)!!.number==1.0) {
                             replaceWithIf(whenStmt.condition, whenStmt.choices[0].statements, null)
@@ -431,6 +503,27 @@ class StatementOptimizer(private val program: Program,
                 }
             }
         }
+
+        val constantValue = whenStmt.condition.constValue(program)?.number
+        if(constantValue!=null) {
+            // when condition is a constant
+            var matchingChoice: WhenChoice? = null
+            loop@ for(choice in whenStmt.choices) {
+                for(value in choice.values ?: emptyList()) {
+                    if(value.constValue(program)?.number == constantValue) {
+                        matchingChoice = choice
+                        break@loop
+                    }
+                }
+            }
+            if(matchingChoice==null)
+                matchingChoice = whenStmt.choices.singleOrNull { it.values==null }
+            if(matchingChoice!=null) {
+                // get rid of the whole when-statement and just leave the matching choice
+                return listOf(IAstModification.ReplaceNode(whenStmt, matchingChoice.statements, parent))
+            }
+        }
+
         return noModifications
     }
 

codeOptimizers/src/prog8/optimizer/UnusedCodeRemover.kt

@@ -66,14 +66,14 @@ class UnusedCodeRemover(private val program: Program,
             if (block.containsNoCodeNorVars) {
                 if(block.name != internedStringsModuleName) {
                     if(!block.statements.any { it is Subroutine && it.hasBeenInlined })
-                        errors.warn("removing unused block '${block.name}'", block.position)
+                        errors.info("removing unused block '${block.name}'", block.position)
                 }
                 return listOf(IAstModification.Remove(block, parent as IStatementContainer))
             }
             if(callgraph.unused(block)) {
                 if(block.statements.any{ it !is VarDecl || it.type== VarDeclType.VAR}) {
                     if(!block.statements.any { it is Subroutine && it.hasBeenInlined })
-                        errors.warn("removing unused block '${block.name}'", block.position)
+                        errors.info("removing unused block '${block.name}'", block.position)
                 }
                 if(!block.statements.any { it is Subroutine && it.hasBeenInlined }) {
                     program.removeInternedStringsFromRemovedBlock(block)
@@ -90,8 +90,8 @@ class UnusedCodeRemover(private val program: Program,
         if (subroutine !== program.entrypoint && !forceOutput && !subroutine.isAsmSubroutine) {
             if(callgraph.unused(subroutine)) {
                 if(subroutine.containsNoCodeNorVars) {
-                    if(!subroutine.definingModule.isLibrary)
-                        errors.warn("removing empty subroutine '${subroutine.name}'", subroutine.position)
+                    if("ignore_unused" !in subroutine.definingBlock.options())
+                        errors.info("removing empty subroutine '${subroutine.name}'", subroutine.position)
                     val removals = mutableListOf(IAstModification.Remove(subroutine, parent as IStatementContainer))
                     callgraph.calledBy[subroutine]?.let {
                         for(node in it)
@@ -99,8 +99,8 @@ class UnusedCodeRemover(private val program: Program,
                     }
                     return removals
                 }
-                if(!subroutine.definingModule.isLibrary && !subroutine.hasBeenInlined) {
-                    errors.warn("unused subroutine '${subroutine.name}'", subroutine.position)
+                if(!subroutine.hasBeenInlined && "ignore_unused" !in subroutine.definingBlock.options()) {
+                    errors.info("unused subroutine '${subroutine.name}'", subroutine.position)
                 }
                 if(!subroutine.inline) {
                     program.removeInternedStringsFromRemovedSubroutine(subroutine)
@@ -119,8 +119,8 @@ class UnusedCodeRemover(private val program: Program,
             if (!forceOutput && decl.origin==VarDeclOrigin.USERCODE && !decl.sharedWithAsm) {
                 val usages = callgraph.usages(decl)
                 if (usages.isEmpty()) {
-                    if(!decl.definingModule.isLibrary)
-                        errors.warn("removing unused variable '${decl.name}'", decl.position)
+                    if("ignore_unused" !in decl.definingBlock.options())
+                        errors.info("removing unused variable '${decl.name}'", decl.position)
                     return listOf(IAstModification.Remove(decl, parent as IStatementContainer))
                 }
                 else {
@@ -131,23 +131,30 @@ class UnusedCodeRemover(private val program: Program,
                             if(assignment!=null && assignment.origin==AssignmentOrigin.VARINIT) {
                                 if(assignment.value.isSimple) {
                                     // remove the vardecl
-                                    if(!decl.definingModule.isLibrary)
-                                        errors.warn("removing unused variable '${decl.name}'", decl.position)
+                                    if("ignore_unused" !in decl.definingBlock.options())
+                                        errors.info("removing unused variable '${decl.name}'", decl.position)
                                     return listOf(
                                         IAstModification.Remove(decl, parent as IStatementContainer),
                                         IAstModification.Remove(assignment, assignment.parent as IStatementContainer)
                                     )
                                 } else if(assignment.value is IFunctionCall) {
                                     // replace the unused variable's initializer function call by a void
-                                    errors.warn("replaced unused variable '${decl.name}' with void call, maybe this can be removed altogether", decl.position)
-                                    val fcall = assignment.value as IFunctionCall
-                                    val voidCall = FunctionCallStatement(fcall.target, fcall.args, true, fcall.position)
-                                    return listOf(
-                                        IAstModification.ReplaceNode(decl, voidCall, parent),
-                                        IAstModification.Remove(assignment, assignment.parent as IStatementContainer)
-                                    )
+                                    // but only if the vardecl immediately precedes it!
+                                    if(singleUse.parent.parent === parent) {
+                                        val declIndex = (parent as IStatementContainer).statements.indexOf(decl)
+                                        val singleUseIndex = (parent as IStatementContainer).statements.indexOf(singleUse.parent)
+                                        if(declIndex==singleUseIndex-1) {
+                                            errors.info("replaced unused variable '${decl.name}' with void call, maybe this can be removed altogether", decl.position)
+                                            val fcall = assignment.value as IFunctionCall
+                                            val voidCall = FunctionCallStatement(fcall.target, fcall.args, true, fcall.position)
+                                            return listOf(
+                                                IAstModification.ReplaceNode(decl, voidCall, parent),
+                                                IAstModification.Remove(assignment, assignment.parent as IStatementContainer)
+                                            )
+                                        }
+                                    }
                                 } else {
-                                    errors.warn("variable '${decl.name}' is unused but has non-trivial initialization assignment. Leaving this in but maybe it can be removed altogether", decl.position)
+                                    errors.info("variable '${decl.name}' is unused but has non-trivial initialization assignment. Leaving this in but maybe it can be removed altogether", decl.position)
                                 }
                             }
                         }

compiler/build.gradle

@@ -33,14 +33,14 @@ dependencies {
     implementation project(':codeGenIntermediate')
     implementation project(':codeGenExperimental')
     implementation project(':virtualmachine')
-    implementation "org.antlr:antlr4-runtime:4.13.0"
+    implementation "org.antlr:antlr4-runtime:4.13.1"
     implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8"
     // implementation "org.jetbrains.kotlin:kotlin-reflect"
-    implementation 'org.jetbrains.kotlinx:kotlinx-cli:0.3.5'
+    implementation 'org.jetbrains.kotlinx:kotlinx-cli:0.3.6'
     implementation "com.michael-bull.kotlin-result:kotlin-result-jvm:1.1.18"
 
     testImplementation project(':intermediate')
-    testImplementation 'io.kotest:kotest-runner-junit5-jvm:5.6.2'
+    testImplementation 'io.kotest:kotest-runner-junit5-jvm:5.8.0'
 }
 
 configurations.all {
@@ -59,10 +59,10 @@ configurations {
 sourceSets {
     main {
         java {
-            srcDirs = ["${project.projectDir}/src"]
+            srcDir "${project.projectDir}/src"
         }
         resources {
-            srcDirs = ["${project.projectDir}/res"]
+            srcDir "${project.projectDir}/res"
         }
     }
     test {

compiler/res/prog8lib/atari/syslib.p8

@@ -1,20 +1,26 @@
 ; Prog8 definitions for the Atari800XL
 ; Including memory registers, I/O registers, Basic and Kernal subroutines.
 
+%option no_symbol_prefixing, ignore_unused
+
 atari {
-    %option no_symbol_prefixing
 
         &uword  NMI_VEC         = $FFFA     ; 6502 nmi vector, determined by the kernal if banked in
         &uword  RESET_VEC       = $FFFC     ; 6502 reset vector, determined by the kernal if banked in
         &uword  IRQ_VEC         = $FFFE     ; 6502 interrupt vector, determined by the kernal if banked in
 
+        &uword COLCRS = 85
+        &ubyte ROWCRS = 84
+
+    romsub $F24A = getchar() -> ubyte @A
+    romsub $F2B0 = outchar(ubyte character @ A)
+    romsub $F2FD = waitkey() -> ubyte @A
+
 }
 
 sys {
     ; ------- lowlevel system routines --------
 
-    %option no_symbol_prefixing
-
     const ubyte target = 8         ;  compilation target specifier.  64 = C64, 128 = C128,  16 = CommanderX16, 8 = atari800XL
 
     asmsub  init_system()  {
@@ -198,9 +204,57 @@ _longcopy
         }}
     }
 
-    inline asmsub exit(ubyte returnvalue @A) {
+    sub disable_caseswitch() {
+        ; no-op
+    }
+
+    sub enable_caseswitch() {
+        ; no-op
+    }
+
+    asmsub save_prog8_internals() {
+        %asm {{
+            lda  P8ZP_SCRATCH_B1
+            sta  save_SCRATCH_ZPB1
+            lda  P8ZP_SCRATCH_REG
+            sta  save_SCRATCH_ZPREG
+            lda  P8ZP_SCRATCH_W1
+            sta  save_SCRATCH_ZPWORD1
+            lda  P8ZP_SCRATCH_W1+1
+            sta  save_SCRATCH_ZPWORD1+1
+            lda  P8ZP_SCRATCH_W2
+            sta  save_SCRATCH_ZPWORD2
+            lda  P8ZP_SCRATCH_W2+1
+            sta  save_SCRATCH_ZPWORD2+1
+            rts
+save_SCRATCH_ZPB1	.byte  0
+save_SCRATCH_ZPREG	.byte  0
+save_SCRATCH_ZPWORD1	.word  0
+save_SCRATCH_ZPWORD2	.word  0
+        }}
+    }
+
+    asmsub restore_prog8_internals() {
+        %asm {{
+            lda  save_prog8_internals.save_SCRATCH_ZPB1
+            sta  P8ZP_SCRATCH_B1
+            lda  save_prog8_internals.save_SCRATCH_ZPREG
+            sta  P8ZP_SCRATCH_REG
+            lda  save_prog8_internals.save_SCRATCH_ZPWORD1
+            sta  P8ZP_SCRATCH_W1
+            lda  save_prog8_internals.save_SCRATCH_ZPWORD1+1
+            sta  P8ZP_SCRATCH_W1+1
+            lda  save_prog8_internals.save_SCRATCH_ZPWORD2
+            sta  P8ZP_SCRATCH_W2
+            lda  save_prog8_internals.save_SCRATCH_ZPWORD2+1
+            sta  P8ZP_SCRATCH_W2+1
+            rts
+        }}
+    }
+
+    asmsub exit(ubyte returnvalue @A) {
         ; -- immediately exit the program with a return code in the A register
-        ;    TODO
+        ;    TODO where to store A as exit code?
         %asm {{
             ldx  prog8_lib.orig_stackpointer
             txs
@@ -215,11 +269,37 @@ _longcopy
         }}
     }
 
+    inline asmsub push(ubyte value @A) {
+        %asm {{
+            pha
+        }}
+    }
+
+    inline asmsub pushw(uword value @AY) {
+        %asm {{
+            pha
+            tya
+            pha
+        }}
+    }
+
+    inline asmsub pop() -> ubyte @A {
+        %asm {{
+            pla
+        }}
+    }
+
+    inline asmsub popw() -> uword @AY {
+        %asm {{
+            pla
+            tay
+            pla
+        }}
+    }
+
 }
 
 cx16 {
-    %option no_symbol_prefixing
-
     ; the sixteen virtual 16-bit registers that the CX16 has defined in the zeropage
     ; they are simulated on the Atari as well but their location in memory is different
     ; TODO
@@ -351,4 +431,9 @@ cx16 {
         }}
     }
 
+    sub cpu_is_65816() -> bool {
+        ; Returns true when you have a 65816 cpu, false when it's a 6502.
+        return false
+    }
+
 }

compiler/res/prog8lib/atari/textio.p8

@@ -1,4 +1,5 @@
 ; Prog8 definitions for the Text I/O and Screen routines for the Atari 800XL
+; Reference:  https://www.atariarchives.org/mapping/appendix12.php
 
 %import syslib
 %import conv
@@ -6,7 +7,7 @@
 
 txt {
 
-    %option no_symbol_prefixing
+    %option no_symbol_prefixing, ignore_unused
 
 const ubyte DEFAULT_WIDTH = 40
 const ubyte DEFAULT_HEIGHT = 24
@@ -24,15 +25,25 @@ sub spc() {
     txt.chrout(' ')
 }
 
-asmsub column(ubyte col @A) clobbers(A, X, Y) {
+sub column(ubyte col) {
     ; ---- set the cursor on the given column (starting with 0) on the current line
-    ;      TODO
-    %asm {{
-        rts
-    }}
+    atari.COLCRS = col
 }
 
-asmsub  fill_screen (ubyte char @ A, ubyte color @ Y) clobbers(A)  {
+sub get_column() -> ubyte {
+    return atari.COLCRS as ubyte
+}
+
+sub row(ubyte rownum) {
+    ; ---- set the cursor on the given row (starting with 0) on the current line
+    atari.ROWCRS = rownum
+}
+
+sub get_row() -> ubyte {
+    return atari.ROWCRS
+}
+
+asmsub  fill_screen (ubyte character @ A, ubyte color @ Y) clobbers(A)  {
     ; ---- fill the character screen with the given fill character and character color.
     ;      (assumes screen and color matrix are at their default addresses)
     ;      TODO
@@ -42,7 +53,7 @@ asmsub  fill_screen (ubyte char @ A, ubyte color @ Y) clobbers(A)  {
     }}
 }
 
-asmsub  clear_screenchars (ubyte char @ A) clobbers(Y)  {
+asmsub  clear_screenchars (ubyte character @ A) clobbers(Y)  {
 	; ---- clear the character screen with the given fill character (leaves colors)
 	;      (assumes screen matrix is at the default address)
 	; TODO
@@ -114,10 +125,7 @@ asmsub  scroll_down  (bool alsocolors @ Pc) clobbers(A)  {
 }
 
 
-romsub $F2B0 = outchar(ubyte char @ A)
-romsub $F2Fd = waitkey()
-
-asmsub chrout(ubyte char @ A) {
+asmsub chrout(ubyte character @ A) {
 	%asm {{
 		sta  _tmp_outchar+1
 		txa
@@ -126,7 +134,7 @@ asmsub chrout(ubyte char @ A) {
 		pha
 _tmp_outchar
 		lda  #0
-		jsr  outchar
+		jsr  atari.outchar
 		pla
 		tay
 		pla
@@ -153,10 +161,9 @@ asmsub  print (str text @ AY) clobbers(A,Y)  {
 	}}
 }
 
-asmsub  print_ub0  (ubyte value @ A) clobbers(A,Y)  {
+asmsub  print_ub0  (ubyte value @ A) clobbers(A,X,Y)  {
 	; ---- print the ubyte in A in decimal form, with left padding 0s (3 positions total)
 	%asm {{
-		stx  P8ZP_SCRATCH_REG
 		jsr  conv.ubyte2decimal
 		pha
 		tya
@@ -164,16 +171,13 @@ asmsub  print_ub0  (ubyte value @ A) clobbers(A,Y)  {
 		pla
 		jsr  chrout
 		txa
-		jsr  chrout
-		ldx  P8ZP_SCRATCH_REG
-		rts
+		jmp  chrout
 	}}
 }
 
-asmsub  print_ub  (ubyte value @ A) clobbers(A,Y)  {
+asmsub  print_ub  (ubyte value @ A) clobbers(A,X,Y)  {
 	; ---- print the ubyte in A in decimal form, without left padding 0s
 	%asm {{
-		stx  P8ZP_SCRATCH_REG
 		jsr  conv.ubyte2decimal
 _print_byte_digits
 		pha
@@ -189,16 +193,13 @@ _print_byte_digits
         beq  _ones
         jsr  chrout
 _ones   txa
-		jsr  chrout
-		ldx  P8ZP_SCRATCH_REG
-		rts
+		jmp  chrout
 	}}
 }
 
-asmsub  print_b  (byte value @ A) clobbers(A,Y)  {
+asmsub  print_b  (byte value @ A) clobbers(A,X,Y)  {
 	; ---- print the byte in A in decimal form, without left padding 0s
 	%asm {{
-		stx  P8ZP_SCRATCH_REG
 		pha
 		cmp  #0
 		bpl  +
@@ -210,10 +211,9 @@ asmsub  print_b  (byte value @ A) clobbers(A,Y)  {
 	}}
 }
 
-asmsub  print_ubhex  (ubyte value @ A, bool prefix @ Pc) clobbers(A,Y)  {
+asmsub  print_ubhex  (ubyte value @ A, bool prefix @ Pc) clobbers(A,X,Y)  {
 	; ---- print the ubyte in A in hex form (if Carry is set, a radix prefix '$' is printed as well)
 	%asm {{
-		stx  P8ZP_SCRATCH_REG
 		bcc  +
 		pha
 		lda  #'$'
@@ -222,16 +222,13 @@ asmsub  print_ubhex  (ubyte value @ A, bool prefix @ Pc) clobbers(A,Y)  {
 +		jsr  conv.ubyte2hex
 		jsr  chrout
 		tya
-		jsr  chrout
-		ldx  P8ZP_SCRATCH_REG
-		rts
+		jmp  chrout
 	}}
 }
 
-asmsub  print_ubbin  (ubyte value @ A, bool prefix @ Pc) clobbers(A,Y)  {
+asmsub  print_ubbin  (ubyte value @ A, bool prefix @ Pc) clobbers(A,X,Y)  {
 	; ---- print the ubyte in A in binary form (if Carry is set, a radix prefix '%' is printed as well)
 	%asm {{
-		stx  P8ZP_SCRATCH_REG
 		sta  P8ZP_SCRATCH_B1
 		bcc  +
 		lda  #'%'
@@ -244,12 +241,11 @@ asmsub  print_ubbin  (ubyte value @ A, bool prefix @ Pc) clobbers(A,Y)  {
 +		jsr  chrout
 		dey
 		bne  -
-		ldx  P8ZP_SCRATCH_REG
 		rts
 	}}
 }
 
-asmsub  print_uwbin  (uword value @ AY, bool prefix @ Pc) clobbers(A,Y)  {
+asmsub  print_uwbin  (uword value @ AY, bool prefix @ Pc) clobbers(A,X,Y)  {
 	; ---- print the uword in A/Y in binary form (if Carry is set, a radix prefix '%' is printed as well)
 	%asm {{
 		pha
@@ -261,7 +257,7 @@ asmsub  print_uwbin  (uword value @ AY, bool prefix @ Pc) clobbers(A,Y)  {
 	}}
 }
 
-asmsub  print_uwhex  (uword value @ AY, bool prefix @ Pc) clobbers(A,Y)  {
+asmsub  print_uwhex  (uword value @ AY, bool prefix @ Pc) clobbers(A,X,Y)  {
 	; ---- print the uword in A/Y in hexadecimal form (4 digits)
 	;      (if Carry is set, a radix prefix '$' is printed as well)
 	%asm {{
@@ -274,10 +270,9 @@ asmsub  print_uwhex  (uword value @ AY, bool prefix @ Pc) clobbers(A,Y)  {
 	}}
 }
 
-asmsub  print_uw0  (uword value @ AY) clobbers(A,Y)  {
+asmsub  print_uw0  (uword value @ AY) clobbers(A,X,Y)  {
 	; ---- print the uword in A/Y in decimal form, with left padding 0s (5 positions total)
 	%asm {{
-	    stx  P8ZP_SCRATCH_REG
 		jsr  conv.uword2decimal
 		ldy  #0
 -		lda  conv.uword2decimal.decTenThousands,y
@@ -285,17 +280,14 @@ asmsub  print_uw0  (uword value @ AY) clobbers(A,Y)  {
 		jsr  chrout
 		iny
 		bne  -
-+		ldx  P8ZP_SCRATCH_REG
-		rts
++		rts
 	}}
 }
 
-asmsub  print_uw  (uword value @ AY) clobbers(A,Y)  {
+asmsub  print_uw  (uword value @ AY) clobbers(A,X,Y)  {
 	; ---- print the uword in A/Y in decimal form, without left padding 0s
 	%asm {{
-	    stx  P8ZP_SCRATCH_REG
 		jsr  conv.uword2decimal
-		ldx  P8ZP_SCRATCH_REG
 		ldy  #0
 -		lda  conv.uword2decimal.decTenThousands,y
 		beq  _allzero
@@ -316,7 +308,7 @@ _allzero
 	}}
 }
 
-asmsub  print_w  (word value @ AY) clobbers(A,Y)  {
+asmsub  print_w  (word value @ AY) clobbers(A,X,Y)  {
 	; ---- print the (signed) word in A/Y in decimal form, without left padding 0's
 	%asm {{
 		cpy  #0
@@ -380,7 +372,7 @@ asmsub  getclr  (ubyte col @A, ubyte row @Y) clobbers(Y) -> ubyte @ A {
         }}
 }
 
-sub  setcc  (ubyte column, ubyte row, ubyte char, ubyte charcolor)  {
+sub  setcc  (ubyte col, ubyte row, ubyte char, ubyte charcolor)  {
 	; ---- set char+color at the given position on the screen
 	; TODO
 	%asm {{
@@ -388,12 +380,20 @@ sub  setcc  (ubyte column, ubyte row, ubyte char, ubyte charcolor)  {
         }}
 }
 
-asmsub  plot  (ubyte col @ Y, ubyte row @ A) clobbers(A) {
-	; ---- set cursor at specific position
-	; TODO
-	%asm  {{
-	    rts
-	}}
+sub  plot(ubyte col, ubyte rownum) {
+    column(col)
+    row(rownum)
+}
+
+sub get_cursor(uword colptr, uword rowptr) {
+    @(colptr) = get_column()
+    @(rowptr) = get_row()
+}
+
+asmsub waitkey() -> ubyte @A {
+    %asm {{
+        jmp  atari.waitkey
+    }}
 }
 
 asmsub width() clobbers(X,Y) -> ubyte @A {

compiler/res/prog8lib/c128/graphics.p8

@@ -1,62 +0,0 @@
-%import syslib
-%import textio
-
-; Bitmap pixel graphics module for the Commodore 128
-
-; TODO c128 actually implement the graphics routines. Ideally a way to 'borrow' the code form the C64 version without just copy-pasting that here?
-
-graphics {
-    %option no_symbol_prefixing
-
-    const uword WIDTH = 320
-    const ubyte HEIGHT = 200
-
-    sub enable_bitmap_mode() {
-        ; enable bitmap screen, erase it and set colors to black/white.
-        ; TODO
-    }
-
-    sub disable_bitmap_mode() {
-        ; enables text mode, erase the text screen, color white
-        ; TODO
-    }
-
-
-    sub clear_screen(ubyte pixelcolor, ubyte bgcolor) {
-        ; TODO
-    }
-
-    sub line(uword @zp x1, ubyte @zp y1, uword @zp x2, ubyte @zp y2) {
-        ; TODO
-    }
-
-    sub fillrect(uword x, uword y, uword width, uword height) {
-        ; TODO
-    }
-
-    sub rect(uword x, uword y, uword width, uword height) {
-        ; TODO
-    }
-
-    sub horizontal_line(uword x, uword y, uword length) {
-        ; TODO
-    }
-
-    sub vertical_line(uword x, uword y, uword height) {
-        ; TODO
-    }
-
-    sub circle(uword xcenter, ubyte ycenter, ubyte radius) {
-        ; TODO
-    }
-
-    sub disc(uword xcenter, ubyte ycenter, ubyte radius) {
-        ; TODO
-    }
-
-    inline asmsub  plot(uword plotx @R0, uword ploty @R1) clobbers(A, X, Y) {
-        %asm {{
-            nop     ; TODO
-        }}
-    }
-}

compiler/res/prog8lib/c128/syslib.p8

@@ -1,9 +1,10 @@
 ; Prog8 definitions for the Commodore-128
 ; Including memory registers, I/O registers, Basic and Kernal subroutines.
 
+%option no_symbol_prefixing, ignore_unused
+
 cbm {
     ; Commodore (CBM) common variables, vectors and kernal routines
-    %option no_symbol_prefixing
 
         &ubyte  TIME_HI         = $a0       ; software jiffy clock, hi byte
         &ubyte  TIME_MID        = $a1       ;  .. mid byte
@@ -78,7 +79,7 @@ romsub $FFAB = UNTLK() clobbers(A)                              ; command serial
 romsub $FFAE = UNLSN() clobbers(A)                              ; command serial bus device to UNLISTEN
 romsub $FFB1 = LISTEN(ubyte device @ A) clobbers(A)             ; command serial bus device to LISTEN
 romsub $FFB4 = TALK(ubyte device @ A) clobbers(A)               ; command serial bus device to TALK
-romsub $FFB7 = READST() -> ubyte @ A                            ; read I/O status word
+romsub $FFB7 = READST() -> ubyte @ A                            ; read I/O status word  (use CLEARST to reset it to 0)
 romsub $FFBA = SETLFS(ubyte logical @ A, ubyte device @ X, ubyte secondary @ Y)   ; set logical file parameters
 romsub $FFBD = SETNAM(ubyte namelen @ A, str filename @ XY)     ; set filename parameters
 romsub $FFC0 = OPEN() clobbers(X,Y) -> bool @Pc, ubyte @A      ; (via 794 ($31A)) open a logical file
@@ -87,7 +88,7 @@ romsub $FFC6 = CHKIN(ubyte logical @ X) clobbers(A,X) -> bool @Pc    ; (via 798
 romsub $FFC9 = CHKOUT(ubyte logical @ X) clobbers(A,X)          ; (via 800 ($320)) define an output channel
 romsub $FFCC = CLRCHN() clobbers(A,X)                           ; (via 802 ($322)) restore default devices
 romsub $FFCF = CHRIN() clobbers(X, Y) -> ubyte @ A   ; (via 804 ($324)) input a character (for keyboard, read a whole line from the screen) A=byte read.
-romsub $FFD2 = CHROUT(ubyte char @ A)                           ; (via 806 ($326)) output a character
+romsub $FFD2 = CHROUT(ubyte character @ A)                           ; (via 806 ($326)) output a character
 romsub $FFD5 = LOAD(ubyte verify @ A, uword address @ XY) -> bool @Pc, ubyte @ A, uword @ XY     ; (via 816 ($330)) load from device
 romsub $FFD8 = SAVE(ubyte zp_startaddr @ A, uword endaddr @ XY) -> bool @ Pc, ubyte @ A          ; (via 818 ($332)) save to a device
 romsub $FFDB = SETTIM(ubyte low @ A, ubyte middle @ X, ubyte high @ Y)      ; set the software clock
@@ -104,44 +105,43 @@ romsub $FFF3 = IOBASE() -> uword @ XY                           ; read base addr
 
 ; ---- utilities -----
 
-asmsub STOP2() -> ubyte @A  {
+asmsub STOP2() clobbers(X) -> ubyte @A  {
     ; -- check if STOP key was pressed, returns true if so.  More convenient to use than STOP() because that only sets the carry status flag.
     %asm {{
-        txa
-        pha
         jsr  cbm.STOP
         beq  +
-        pla
-        tax
         lda  #0
         rts
-+       pla
-        tax
-        lda  #1
++       lda  #1
         rts
     }}
 }
 
-asmsub RDTIM16() -> uword @AY {
+asmsub RDTIM16() clobbers(X) -> uword @AY {
     ; --  like RDTIM() but only returning the lower 16 bits in AY for convenience
     %asm {{
-        stx  P8ZP_SCRATCH_REG
         jsr  cbm.RDTIM
         pha
         txa
         tay
         pla
-        ldx  P8ZP_SCRATCH_REG
         rts
     }}
 }
 
+sub CLEARST() {
+    ; -- Set the ST status variable back to 0. (there's no direct kernal call for this)
+    ;    Note: a drive error state (blinking led) isn't cleared! You can use diskio.status() to clear that.
+    SETNAM(0, $0000)
+    SETLFS(15, 3, 15)
+    void OPEN()
+    CLOSE(15)
+}
 
 }
 
 c64 {
         ; C64 I/O registers (VIC, SID, CIA)
-    %option no_symbol_prefixing
 
         ; the default locations of the 8 sprite pointers (store address of sprite / 64)
         &ubyte  SPRPTR0         = 2040
@@ -296,7 +296,6 @@ c64 {
 
 c128 {
 ; ---- C128 specific registers ----
-    %option no_symbol_prefixing
 
     &ubyte  VM1     = $0A2C         ; shadow for VUC $d018 in text mode
     &ubyte  VM2     = $0A2D         ; shadow for VIC $d018 in bitmap screen mode
@@ -333,7 +332,6 @@ asmsub  disable_basic() clobbers(A) {
 
 sys {
     ; ------- lowlevel system routines --------
-    %option no_symbol_prefixing
 
     const ubyte target = 128         ;  compilation target specifier.  64 = C64, 128 = C128,  16 = CommanderX16.
 
@@ -343,7 +341,7 @@ asmsub  init_system()  {
     ; This means that the BASIC, KERNAL and CHARGEN ROMs are banked in,
     ; the VIC, SID and CIA chips are reset, screen is cleared, and the default IRQ is set.
     ; Also a different color scheme is chosen to identify ourselves a little.
-    ; Uppercase charset is activated, and all three registers set to 0, status flags cleared.
+    ; Uppercase charset is activated.
     %asm {{
         sei
         cld
@@ -375,7 +373,13 @@ asmsub  init_system_phase2()  {
 asmsub  cleanup_at_exit() {
     ; executed when the main subroutine does rts
     %asm {{
-        jmp  sys.enable_runstop_and_charsetswitch
+        lda  #0
+        sta  $ff00          ; default bank 15
+        jsr  cbm.CLRCHN		; reset i/o channels
+        jsr  enable_runstop_and_charsetswitch
+_exitcode = *+1
+        lda  #0        ; exit code possibly modified in exit()
+        rts
     }}
 }
 
@@ -399,81 +403,78 @@ asmsub  enable_runstop_and_charsetswitch() clobbers(A) {
     }}
 }
 
-asmsub  set_irq(uword handler @AY, bool useKernal @Pc) clobbers(A)  {
+    asmsub save_prog8_internals() {
+        %asm {{
+            lda  P8ZP_SCRATCH_B1
+            sta  save_SCRATCH_ZPB1
+            lda  P8ZP_SCRATCH_REG
+            sta  save_SCRATCH_ZPREG
+            lda  P8ZP_SCRATCH_W1
+            sta  save_SCRATCH_ZPWORD1
+            lda  P8ZP_SCRATCH_W1+1
+            sta  save_SCRATCH_ZPWORD1+1
+            lda  P8ZP_SCRATCH_W2
+            sta  save_SCRATCH_ZPWORD2
+            lda  P8ZP_SCRATCH_W2+1
+            sta  save_SCRATCH_ZPWORD2+1
+            rts
+save_SCRATCH_ZPB1	.byte  0
+save_SCRATCH_ZPREG	.byte  0
+save_SCRATCH_ZPWORD1	.word  0
+save_SCRATCH_ZPWORD2	.word  0
+        }}
+    }
+
+    asmsub restore_prog8_internals() {
+        %asm {{
+            lda  save_prog8_internals.save_SCRATCH_ZPB1
+            sta  P8ZP_SCRATCH_B1
+            lda  save_prog8_internals.save_SCRATCH_ZPREG
+            sta  P8ZP_SCRATCH_REG
+            lda  save_prog8_internals.save_SCRATCH_ZPWORD1
+            sta  P8ZP_SCRATCH_W1
+            lda  save_prog8_internals.save_SCRATCH_ZPWORD1+1
+            sta  P8ZP_SCRATCH_W1+1
+            lda  save_prog8_internals.save_SCRATCH_ZPWORD2
+            sta  P8ZP_SCRATCH_W2
+            lda  save_prog8_internals.save_SCRATCH_ZPWORD2+1
+            sta  P8ZP_SCRATCH_W2+1
+            rts
+        }}
+    }
+
+asmsub  set_irq(uword handler @AY) clobbers(A)  {
 	%asm {{
-	        sta  _modified+1
-	        sty  _modified+2
-	        lda  #0
-	        rol  a
-	        sta  _use_kernal
 		sei
+        sta  _modified+1
+        sty  _modified+2
 		lda  #<_irq_handler
 		sta  cbm.CINV
 		lda  #>_irq_handler
 		sta  cbm.CINV+1
 		cli
 		rts
-_irq_handler    jsr  _irq_handler_init
-_modified	jsr  $ffff                      ; modified
-		jsr  _irq_handler_end
-		lda  _use_kernal
-		bne  +
-		lda  #$ff
+_irq_handler
+        jsr  sys.save_prog8_internals
+        cld
+_modified
+        jsr  $ffff                      ; modified
+        pha
+        jsr  sys.restore_prog8_internals
+        pla
+        beq  +
+		jmp  cbm.IRQDFRT		; continue with normal kernal irq routine
++		lda  #$ff
 		sta  c64.VICIRQ			; acknowledge raster irq
 		lda  c64.CIA1ICR		; acknowledge CIA1 interrupt
-		; end irq processing - don't use kernal's irq handling
 		pla
 		tay
 		pla
 		tax
 		pla
 		rti
-+		jmp  cbm.IRQDFRT		; continue with normal kernal irq routine
 
 _use_kernal     .byte  0
-
-_irq_handler_init
-		; save all zp scratch registers as these might be clobbered by the irq routine
-		lda  P8ZP_SCRATCH_B1
-		sta  IRQ_SCRATCH_ZPB1
-		lda  P8ZP_SCRATCH_REG
-		sta  IRQ_SCRATCH_ZPREG
-		lda  P8ZP_SCRATCH_W1
-		sta  IRQ_SCRATCH_ZPWORD1
-		lda  P8ZP_SCRATCH_W1+1
-		sta  IRQ_SCRATCH_ZPWORD1+1
-		lda  P8ZP_SCRATCH_W2
-		sta  IRQ_SCRATCH_ZPWORD2
-		lda  P8ZP_SCRATCH_W2+1
-		sta  IRQ_SCRATCH_ZPWORD2+1
-		; Set X to the bottom 32 bytes of the evaluation stack, to HOPEFULLY not clobber it.
-		; This leaves 128-32=96 stack entries for the main program, and 32 stack entries for the IRQ handler.
-		; We assume IRQ handlers don't contain complex expressions taking up more than that.
-		ldx  #32
-		cld
-		rts
-
-_irq_handler_end
-		; restore all zp scratch registers
-		lda  IRQ_SCRATCH_ZPB1
-		sta  P8ZP_SCRATCH_B1
-		lda  IRQ_SCRATCH_ZPREG
-		sta  P8ZP_SCRATCH_REG
-		lda  IRQ_SCRATCH_ZPWORD1
-		sta  P8ZP_SCRATCH_W1
-		lda  IRQ_SCRATCH_ZPWORD1+1
-		sta  P8ZP_SCRATCH_W1+1
-		lda  IRQ_SCRATCH_ZPWORD2
-		sta  P8ZP_SCRATCH_W2
-		lda  IRQ_SCRATCH_ZPWORD2+1
-		sta  P8ZP_SCRATCH_W2+1
-		rts
-
-IRQ_SCRATCH_ZPB1	.byte  0
-IRQ_SCRATCH_ZPREG	.byte  0
-IRQ_SCRATCH_ZPWORD1	.word  0
-IRQ_SCRATCH_ZPWORD2	.word  0
-
 		}}
 }
 
@@ -493,40 +494,39 @@ asmsub  restore_irq() clobbers(A) {
 	}}
 }
 
-asmsub  set_rasterirq(uword handler @AY, uword rasterpos @R0, bool useKernal @Pc) clobbers(A) {
+asmsub  set_rasterirq(uword handler @AY, uword rasterpos @R0) clobbers(A) {
 	%asm {{
-	        sta  _modified+1
-	        sty  _modified+2
-	        lda  #0
-	        rol  a
-	        sta  set_irq._use_kernal
-		lda  cx16.r0
-		ldy  cx16.r0+1
-		sei
-		jsr  _setup_raster_irq
-		lda  #<_raster_irq_handler
-		sta  cbm.CINV
-		lda  #>_raster_irq_handler
-		sta  cbm.CINV+1
-		cli
-		rts
+        sei
+        sta  _modified+1
+        sty  _modified+2
+        lda  cx16.r0
+        ldy  cx16.r0+1
+        jsr  _setup_raster_irq
+        lda  #<_raster_irq_handler
+        sta  cbm.CINV
+        lda  #>_raster_irq_handler
+        sta  cbm.CINV+1
+        cli
+        rts
 
 _raster_irq_handler
-		jsr  set_irq._irq_handler_init
-_modified	jsr  $ffff              ; modified
-		jsr  set_irq._irq_handler_end
+		jsr  sys.save_prog8_internals
+		cld
+_modified
+        jsr  $ffff              ; modified
+        pha
+		jsr  sys.restore_prog8_internals
         lda  #$ff
         sta  c64.VICIRQ			; acknowledge raster irq
-		lda  set_irq._use_kernal
-		bne  +
-		; end irq processing - don't use kernal's irq handling
 		pla
+		beq  +
+		jmp  cbm.IRQDFRT        ; continue with kernal irq routine
++		pla
 		tay
 		pla
 		tax
 		pla
 		rti
-+		jmp  cbm.IRQDFRT                ; continue with kernal irq routine
 
 _setup_raster_irq
 		pha
@@ -746,16 +746,27 @@ _longcopy
         }}
     }
 
-    inline asmsub exit(ubyte returnvalue @A) {
-        ; -- immediately exit the program with a return code in the A register
+    inline asmsub disable_caseswitch() {
+        %asm {{
+            lda  #$80
+            sta  247
+        }}
+    }
+
+    inline asmsub enable_caseswitch() {
         %asm {{
             lda  #0
-            sta  $ff00          ; default bank 15
-            jsr  cbm.CLRCHN		; reset i/o channels
-            jsr  sys.enable_runstop_and_charsetswitch
+            sta  247
+        }}
+    }
+
+    asmsub exit(ubyte returnvalue @A) {
+        ; -- immediately exit the program with a return code in the A register
+        %asm {{
+            sta  cleanup_at_exit._exitcode
             ldx  prog8_lib.orig_stackpointer
             txs
-            rts		; return to original caller
+            jmp  cleanup_at_exit
         }}
     }
 
@@ -766,119 +777,142 @@ _longcopy
         }}
     }
 
+    inline asmsub push(ubyte value @A) {
+        %asm {{
+            pha
+        }}
+    }
+
+    inline asmsub pushw(uword value @AY) {
+        %asm {{
+            pha
+            tya
+            pha
+        }}
+    }
+
+    inline asmsub pop() -> ubyte @A {
+        %asm {{
+            pla
+        }}
+    }
+
+    inline asmsub popw() -> uword @AY {
+        %asm {{
+            pla
+            tay
+            pla
+        }}
+    }
+
 }
 
 cx16 {
-    %option no_symbol_prefixing
-
     ; the sixteen virtual 16-bit registers that the CX16 has defined in the zeropage
     ; they are simulated on the C128 as well but their location in memory is different
     ; (because there's no room for them in the zeropage)
-    ; $1300-$1bff is unused RAM on C128. We'll use $1a00-$1bff as the lo/hi evalstack.
-    ; the virtual registers are allocated at the bottom of the eval-stack (should be ample space unless
-    ; you're doing insane nesting of expressions...)
-    ; NOTE: the memory location of these registers can change based on the "-esa" compiler option
-    &uword r0  = $1b00
-    &uword r1  = $1b02
-    &uword r2  = $1b04
-    &uword r3  = $1b06
-    &uword r4  = $1b08
-    &uword r5  = $1b0a
-    &uword r6  = $1b0c
-    &uword r7  = $1b0e
-    &uword r8  = $1b10
-    &uword r9  = $1b12
-    &uword r10 = $1b14
-    &uword r11 = $1b16
-    &uword r12 = $1b18
-    &uword r13 = $1b1a
-    &uword r14 = $1b1c
-    &uword r15 = $1b1e
+    ; $1300-$1bff is unused RAM on C128.
+    &uword r0  = $1be0
+    &uword r1  = $1be2
+    &uword r2  = $1be4
+    &uword r3  = $1be6
+    &uword r4  = $1be8
+    &uword r5  = $1bea
+    &uword r6  = $1bec
+    &uword r7  = $1bee
+    &uword r8  = $1bf0
+    &uword r9  = $1bf2
+    &uword r10 = $1bf4
+    &uword r11 = $1bf6
+    &uword r12 = $1bf8
+    &uword r13 = $1bfa
+    &uword r14 = $1bfc
+    &uword r15 = $1bfe
 
-    &word r0s  = $1b00
-    &word r1s  = $1b02
-    &word r2s  = $1b04
-    &word r3s  = $1b06
-    &word r4s  = $1b08
-    &word r5s  = $1b0a
-    &word r6s  = $1b0c
-    &word r7s  = $1b0e
-    &word r8s  = $1b10
-    &word r9s  = $1b12
-    &word r10s = $1b14
-    &word r11s = $1b16
-    &word r12s = $1b18
-    &word r13s = $1b1a
-    &word r14s = $1b1c
-    &word r15s = $1b1e
+    &word r0s  = $1be0
+    &word r1s  = $1be2
+    &word r2s  = $1be4
+    &word r3s  = $1be6
+    &word r4s  = $1be8
+    &word r5s  = $1bea
+    &word r6s  = $1bec
+    &word r7s  = $1bee
+    &word r8s  = $1bf0
+    &word r9s  = $1bf2
+    &word r10s = $1bf4
+    &word r11s = $1bf6
+    &word r12s = $1bf8
+    &word r13s = $1bfa
+    &word r14s = $1bfc
+    &word r15s = $1bfe
 
-    &ubyte r0L  = $1b00
-    &ubyte r1L  = $1b02
-    &ubyte r2L  = $1b04
-    &ubyte r3L  = $1b06
-    &ubyte r4L  = $1b08
-    &ubyte r5L  = $1b0a
-    &ubyte r6L  = $1b0c
-    &ubyte r7L  = $1b0e
-    &ubyte r8L  = $1b10
-    &ubyte r9L  = $1b12
-    &ubyte r10L = $1b14
-    &ubyte r11L = $1b16
-    &ubyte r12L = $1b18
-    &ubyte r13L = $1b1a
-    &ubyte r14L = $1b1c
-    &ubyte r15L = $1b1e
+    &ubyte r0L  = $1be0
+    &ubyte r1L  = $1be2
+    &ubyte r2L  = $1be4
+    &ubyte r3L  = $1be6
+    &ubyte r4L  = $1be8
+    &ubyte r5L  = $1bea
+    &ubyte r6L  = $1bec
+    &ubyte r7L  = $1bee
+    &ubyte r8L  = $1bf0
+    &ubyte r9L  = $1bf2
+    &ubyte r10L = $1bf4
+    &ubyte r11L = $1bf6
+    &ubyte r12L = $1bf8
+    &ubyte r13L = $1bfa
+    &ubyte r14L = $1bfc
+    &ubyte r15L = $1bfe
 
-    &ubyte r0H  = $1b01
-    &ubyte r1H  = $1b03
-    &ubyte r2H  = $1b05
-    &ubyte r3H  = $1b07
-    &ubyte r4H  = $1b09
-    &ubyte r5H  = $1b0b
-    &ubyte r6H  = $1b0d
-    &ubyte r7H  = $1b0f
-    &ubyte r8H  = $1b11
-    &ubyte r9H  = $1b13
-    &ubyte r10H = $1b15
-    &ubyte r11H = $1b17
-    &ubyte r12H = $1b19
-    &ubyte r13H = $1b1b
-    &ubyte r14H = $1b1d
-    &ubyte r15H = $1b1f
+    &ubyte r0H  = $1be1
+    &ubyte r1H  = $1be3
+    &ubyte r2H  = $1be5
+    &ubyte r3H  = $1be7
+    &ubyte r4H  = $1be9
+    &ubyte r5H  = $1beb
+    &ubyte r6H  = $1bed
+    &ubyte r7H  = $1bef
+    &ubyte r8H  = $1bf1
+    &ubyte r9H  = $1bf3
+    &ubyte r10H = $1bf5
+    &ubyte r11H = $1bf7
+    &ubyte r12H = $1bf9
+    &ubyte r13H = $1bfb
+    &ubyte r14H = $1bfd
+    &ubyte r15H = $1bff
 
-    &byte r0sL  = $1b00
-    &byte r1sL  = $1b02
-    &byte r2sL  = $1b04
-    &byte r3sL  = $1b06
-    &byte r4sL  = $1b08
-    &byte r5sL  = $1b0a
-    &byte r6sL  = $1b0c
-    &byte r7sL  = $1b0e
-    &byte r8sL  = $1b10
-    &byte r9sL  = $1b12
-    &byte r10sL = $1b14
-    &byte r11sL = $1b16
-    &byte r12sL = $1b18
-    &byte r13sL = $1b1a
-    &byte r14sL = $1b1c
-    &byte r15sL = $1b1e
+    &byte r0sL  = $1be0
+    &byte r1sL  = $1be2
+    &byte r2sL  = $1be4
+    &byte r3sL  = $1be6
+    &byte r4sL  = $1be8
+    &byte r5sL  = $1bea
+    &byte r6sL  = $1bec
+    &byte r7sL  = $1bee
+    &byte r8sL  = $1bf0
+    &byte r9sL  = $1bf2
+    &byte r10sL = $1bf4
+    &byte r11sL = $1bf6
+    &byte r12sL = $1bf8
+    &byte r13sL = $1bfa
+    &byte r14sL = $1bfc
+    &byte r15sL = $1bfe
 
-    &byte r0sH  = $1b01
-    &byte r1sH  = $1b03
-    &byte r2sH  = $1b05
-    &byte r3sH  = $1b07
-    &byte r4sH  = $1b09
-    &byte r5sH  = $1b0b
-    &byte r6sH  = $1b0d
-    &byte r7sH  = $1b0f
-    &byte r8sH  = $1b11
-    &byte r9sH  = $1b13
-    &byte r10sH = $1b15
-    &byte r11sH = $1b17
-    &byte r12sH = $1b19
-    &byte r13sH = $1b1b
-    &byte r14sH = $1b1d
-    &byte r15sH = $1b1f
+    &byte r0sH  = $1be1
+    &byte r1sH  = $1be3
+    &byte r2sH  = $1be5
+    &byte r3sH  = $1be7
+    &byte r4sH  = $1be9
+    &byte r5sH  = $1beb
+    &byte r6sH  = $1bed
+    &byte r7sH  = $1bef
+    &byte r8sH  = $1bf1
+    &byte r9sH  = $1bf3
+    &byte r10sH = $1bf5
+    &byte r11sH = $1bf7
+    &byte r12sH = $1bf9
+    &byte r13sH = $1bfb
+    &byte r14sH = $1bfd
+    &byte r15sH = $1bff
 
     asmsub save_virtual_registers() clobbers(A,Y) {
         %asm {{
@@ -905,4 +939,10 @@ cx16 {
             rts
         }}
     }
+
+    sub cpu_is_65816() -> bool {
+        ; Returns true when you have a 65816 cpu, false when it's a 6502.
+        return false
+    }
+
 }

compiler/res/prog8lib/c128/textio.p8

@@ -1,11 +1,13 @@
-; Prog8 definitions for the Text I/O and Screen routines for the Commodore-64
+; Prog8 definitions for the Text I/O and Screen routines for the Commodore-128
+; All routines work with Screencode character encoding, except `print`, `chrout` and `input_chars`,
+; these work with PETSCII encoding instead.
 
 %import syslib
 %import conv
 
 
 txt {
-    %option no_symbol_prefixing
+    %option no_symbol_prefixing, ignore_unused
 
 const ubyte DEFAULT_WIDTH = 40
 const ubyte DEFAULT_HEIGHT = 25
@@ -38,6 +40,45 @@ asmsub column(ubyte col @A) clobbers(A, X, Y) {
     }}
 }
 
+
+asmsub get_column() -> ubyte @Y {
+    %asm {{
+        sec
+        jmp cbm.PLOT
+    }}
+}
+
+asmsub row(ubyte rownum @A) clobbers(A, X, Y) {
+    ; ---- set the cursor on the given row (starting with 0) on the current line
+    %asm {{
+        sec
+        jsr  cbm.PLOT
+        tax
+        clc
+        jmp  cbm.PLOT
+    }}
+}
+
+asmsub get_row() -> ubyte @X {
+    %asm {{
+        sec
+        jmp cbm.PLOT
+    }}
+}
+
+sub get_cursor(uword colptr, uword rowptr) {
+    %asm {{
+        sec
+        jsr cbm.PLOT
+        tya
+        ldy #$00
+        sta (colptr),y
+        txa
+        sta (rowptr),y
+    }}
+}
+
+
 asmsub  fill_screen (ubyte char @ A, ubyte color @ Y) clobbers(A)  {
 	; ---- fill the character screen with the given fill character and character color.
 	;      (assumes screen and color matrix are at their default addresses)
@@ -97,13 +138,12 @@ sub uppercase() {
     c128.VM1 &= ~2
 }
 
-asmsub  scroll_left  (bool alsocolors @ Pc) clobbers(A, Y)  {
+asmsub  scroll_left  (bool alsocolors @ Pc) clobbers(A, X, Y)  {
 	; ---- scroll the whole screen 1 character to the left
 	;      contents of the rightmost column are unchanged, you should clear/refill this yourself
 	;      Carry flag determines if screen color data must be scrolled too
 
 	%asm {{
-		stx  P8ZP_SCRATCH_REG
 		bcc _scroll_screen
 
 +               ; scroll the screen and the color memory
@@ -133,17 +173,15 @@ _scroll_screen  ; scroll only the screen memory
 		dey
 		bpl  -
 
-		ldx  P8ZP_SCRATCH_REG
 		rts
 	}}
 }
 
-asmsub  scroll_right  (bool alsocolors @ Pc) clobbers(A)  {
+asmsub  scroll_right  (bool alsocolors @ Pc) clobbers(A,X)  {
 	; ---- scroll the whole screen 1 character to the right
 	;      contents of the leftmost column are unchanged, you should clear/refill this yourself
 	;      Carry flag determines if screen color data must be scrolled too
 	%asm {{
-		stx  P8ZP_SCRATCH_REG
 		bcc  _scroll_screen
 
 +               ; scroll the screen and the color memory
@@ -169,17 +207,15 @@ _scroll_screen  ; scroll only the screen memory
 		dex
 		bpl  -
 
-		ldx  P8ZP_SCRATCH_REG
 		rts
 	}}
 }
 
-asmsub  scroll_up  (bool alsocolors @ Pc) clobbers(A)  {
+asmsub  scroll_up  (bool alsocolors @ Pc) clobbers(A,X)  {
 	; ---- scroll the whole screen 1 character up
 	;      contents of the bottom row are unchanged, you should refill/clear this yourself
 	;      Carry flag determines if screen color data must be scrolled too
 	%asm {{
-		stx  P8ZP_SCRATCH_REG
 		bcc  _scroll_screen
 
 +               ; scroll the screen and the color memory
@@ -205,17 +241,15 @@ _scroll_screen  ; scroll only the screen memory
 		dex
 		bpl  -
 
-		ldx  P8ZP_SCRATCH_REG
 		rts
 	}}
 }
 
-asmsub  scroll_down  (bool alsocolors @ Pc) clobbers(A)  {
+asmsub  scroll_down  (bool alsocolors @ Pc) clobbers(A,X)  {
 	; ---- scroll the whole screen 1 character down
 	;      contents of the top row are unchanged, you should refill/clear this yourself
 	;      Carry flag determines if screen color data must be scrolled too
 	%asm {{
-		stx  P8ZP_SCRATCH_REG
 		bcc  _scroll_screen
 
 +               ; scroll the screen and the color memory
@@ -241,15 +275,14 @@ _scroll_screen  ; scroll only the screen memory
 		dex
 		bpl  -
 
-		ldx  P8ZP_SCRATCH_REG
 		rts
 	}}
 }
 
-romsub $FFD2 = chrout(ubyte char @ A)    ; for consistency. You can also use cbm.CHROUT directly ofcourse.
+romsub $FFD2 = chrout(ubyte char @ A)    ; for consistency. You can also use cbm.CHROUT directly ofcourse. Note: takes a PETSCII encoded character.
 
 asmsub  print (str text @ AY) clobbers(A,Y)  {
-	; ---- print null terminated string from A/Y
+	; ---- print null terminated string, in PETSCII encoding, from A/Y
 	; note: the compiler contains an optimization that will replace
 	;       a call to this subroutine with a string argument of just one char,
 	;       by just one call to cbm.CHROUT of that single char.
@@ -266,10 +299,9 @@ asmsub  print (str text @ AY) clobbers(A,Y)  {
 	}}
 }
 
-asmsub  print_ub0  (ubyte value @ A) clobbers(A,Y)  {
+asmsub  print_ub0  (ubyte value @ A) clobbers(A,X,Y)  {
 	; ---- print the ubyte in A in decimal form, with left padding 0s (3 positions total)
 	%asm {{
-		stx  P8ZP_SCRATCH_REG
 		jsr  conv.ubyte2decimal
 		pha
 		tya
@@ -277,16 +309,13 @@ asmsub  print_ub0  (ubyte value @ A) clobbers(A,Y)  {
 		pla
 		jsr  cbm.CHROUT
 		txa
-		jsr  cbm.CHROUT
-		ldx  P8ZP_SCRATCH_REG
-		rts
+		jmp  cbm.CHROUT
 	}}
 }
 
-asmsub  print_ub  (ubyte value @ A) clobbers(A,Y)  {
+asmsub  print_ub  (ubyte value @ A) clobbers(A,X,Y)  {
 	; ---- print the ubyte in A in decimal form, without left padding 0s
 	%asm {{
-		stx  P8ZP_SCRATCH_REG
 		jsr  conv.ubyte2decimal
 _print_byte_digits
 		pha
@@ -302,16 +331,13 @@ _print_byte_digits
         beq  _ones
         jsr  cbm.CHROUT
 _ones   txa
-		jsr  cbm.CHROUT
-		ldx  P8ZP_SCRATCH_REG
-		rts
+		jmp  cbm.CHROUT
 	}}
 }
 
-asmsub  print_b  (byte value @ A) clobbers(A,Y)  {
+asmsub  print_b  (byte value @ A) clobbers(A,X,Y)  {
 	; ---- print the byte in A in decimal form, without left padding 0s
 	%asm {{
-		stx  P8ZP_SCRATCH_REG
 		pha
 		cmp  #0
 		bpl  +
@@ -323,10 +349,9 @@ asmsub  print_b  (byte value @ A) clobbers(A,Y)  {
 	}}
 }
 
-asmsub  print_ubhex  (ubyte value @ A, bool prefix @ Pc) clobbers(A,Y)  {
+asmsub  print_ubhex  (ubyte value @ A, bool prefix @ Pc) clobbers(A,X,Y)  {
 	; ---- print the ubyte in A in hex form (if Carry is set, a radix prefix '$' is printed as well)
 	%asm {{
-		stx  P8ZP_SCRATCH_REG
 		bcc  +
 		pha
 		lda  #'$'
@@ -335,16 +360,13 @@ asmsub  print_ubhex  (ubyte value @ A, bool prefix @ Pc) clobbers(A,Y)  {
 +		jsr  conv.ubyte2hex
 		jsr  cbm.CHROUT
 		tya
-		jsr  cbm.CHROUT
-		ldx  P8ZP_SCRATCH_REG
-		rts
+		jmp  cbm.CHROUT
 	}}
 }
 
-asmsub  print_ubbin  (ubyte value @ A, bool prefix @ Pc) clobbers(A,Y)  {
+asmsub  print_ubbin  (ubyte value @ A, bool prefix @ Pc) clobbers(A,X,Y)  {
 	; ---- print the ubyte in A in binary form (if Carry is set, a radix prefix '%' is printed as well)
 	%asm {{
-		stx  P8ZP_SCRATCH_REG
 		sta  P8ZP_SCRATCH_B1
 		bcc  +
 		lda  #'%'
@@ -357,12 +379,11 @@ asmsub  print_ubbin  (ubyte value @ A, bool prefix @ Pc) clobbers(A,Y)  {
 +		jsr  cbm.CHROUT
 		dey
 		bne  -
-		ldx  P8ZP_SCRATCH_REG
 		rts
 	}}
 }
 
-asmsub  print_uwbin  (uword value @ AY, bool prefix @ Pc) clobbers(A,Y)  {
+asmsub  print_uwbin  (uword value @ AY, bool prefix @ Pc) clobbers(A,X,Y)  {
 	; ---- print the uword in A/Y in binary form (if Carry is set, a radix prefix '%' is printed as well)
 	%asm {{
 		pha
@@ -374,7 +395,7 @@ asmsub  print_uwbin  (uword value @ AY, bool prefix @ Pc) clobbers(A,Y)  {
 	}}
 }
 
-asmsub  print_uwhex  (uword value @ AY, bool prefix @ Pc) clobbers(A,Y)  {
+asmsub  print_uwhex  (uword value @ AY, bool prefix @ Pc) clobbers(A,X,Y)  {
 	; ---- print the uword in A/Y in hexadecimal form (4 digits)
 	;      (if Carry is set, a radix prefix '$' is printed as well)
 	%asm {{
@@ -387,10 +408,9 @@ asmsub  print_uwhex  (uword value @ AY, bool prefix @ Pc) clobbers(A,Y)  {
 	}}
 }
 
-asmsub  print_uw0  (uword value @ AY) clobbers(A,Y)  {
+asmsub  print_uw0  (uword value @ AY) clobbers(A,X,Y)  {
 	; ---- print the uword in A/Y in decimal form, with left padding 0s (5 positions total)
 	%asm {{
-	    stx  P8ZP_SCRATCH_REG
 		jsr  conv.uword2decimal
 		ldy  #0
 -		lda  conv.uword2decimal.decTenThousands,y
@@ -398,17 +418,14 @@ asmsub  print_uw0  (uword value @ AY) clobbers(A,Y)  {
 		jsr  cbm.CHROUT
 		iny
 		bne  -
-+		ldx  P8ZP_SCRATCH_REG
-		rts
++		rts
 	}}
 }
 
-asmsub  print_uw  (uword value @ AY) clobbers(A,Y)  {
+asmsub  print_uw  (uword value @ AY) clobbers(A,X,Y)  {
 	; ---- print the uword in A/Y in decimal form, without left padding 0s
 	%asm {{
-	    stx  P8ZP_SCRATCH_REG
 		jsr  conv.uword2decimal
-		ldx  P8ZP_SCRATCH_REG
 		ldy  #0
 -		lda  conv.uword2decimal.decTenThousands,y
 		beq  _allzero
@@ -429,7 +446,7 @@ _allzero
 	}}
 }
 
-asmsub  print_w  (word value @ AY) clobbers(A,Y)  {
+asmsub  print_w  (word value @ AY) clobbers(A,X,Y)  {
 	; ---- print the (signed) word in A/Y in decimal form, without left padding 0's
 	%asm {{
 		cpy  #0
@@ -451,7 +468,8 @@ asmsub  print_w  (word value @ AY) clobbers(A,Y)  {
 }
 
 asmsub  input_chars  (uword buffer @ AY) clobbers(A) -> ubyte @ Y  {
-	; ---- Input a string (max. 80 chars) from the keyboard. Returns length in Y. (string is terminated with a 0 byte as well)
+	; ---- Input a string (max. 80 chars) from the keyboard, in PETSCII encoding.
+	;      Returns length in Y. (string is terminated with a 0 byte as well)
 	;      It assumes the keyboard is selected as I/O channel!
 
 	%asm {{
@@ -490,7 +508,7 @@ asmsub  setchr  (ubyte col @X, ubyte row @Y, ubyte character @A) clobbers(A, Y)
 _mod		sta  $ffff		; modified
 		rts
 
-_screenrows	.word  $0400 + range(0, 1000, 40)
+_screenrows	.word  cbm.Screen + range(0, 1000, 40)
 	}}
 }
 
@@ -557,7 +575,7 @@ _mod		lda  $ffff		; modified
 	}}
 }
 
-sub  setcc  (ubyte column, ubyte row, ubyte char, ubyte charcolor)  {
+sub  setcc  (ubyte col, ubyte row, ubyte character, ubyte charcolor)  {
 	; ---- set char+color at the given position on the screen
 	%asm {{
 		lda  row
@@ -569,13 +587,13 @@ sub  setcc  (ubyte column, ubyte row, ubyte char, ubyte charcolor)  {
 		sta  _colormod+2
 		lda  setchr._screenrows,y
 		clc
-		adc  column
+		adc  col
 		sta  _charmod+1
 		sta  _colormod+1
 		bcc  +
 		inc  _charmod+2
 		inc  _colormod+2
-+		lda  char
++		lda  character
 _charmod	sta  $ffff		; modified
 		lda  charcolor
 _colormod	sta  $ffff		; modified
@@ -583,15 +601,10 @@ _colormod	sta  $ffff		; modified
 	}}
 }
 
-asmsub  plot  (ubyte col @ Y, ubyte row @ A) clobbers(A) {
-	; ---- safe wrapper around PLOT kernal routine, to save the X register.
+asmsub  plot  (ubyte col @ Y, ubyte row @ X) {
 	%asm  {{
-		stx  P8ZP_SCRATCH_REG
-		tax
 		clc
-		jsr  cbm.PLOT
-		ldx  P8ZP_SCRATCH_REG
-		rts
+		jmp  cbm.PLOT
 	}}
 }
 
@@ -613,4 +626,11 @@ asmsub height() clobbers(X, Y) -> ubyte @A {
     }}
 }
 
+asmsub waitkey() -> ubyte @A {
+    %asm {{
+-       jsr cbm.GETIN
+        beq -
+        rts
+    }}
+}
 }

compiler/res/prog8lib/c64/floats.asm

@@ -5,13 +5,11 @@ FL_ZERO_const	.byte  0,0,0,0,0		; 0.0
 FL_LOG2_const	.byte  $80, $31, $72, $17, $f8	; log(2)
 
 
-floats_store_reg	.byte  0		; temp storage
 floats_temp_var         .byte  0,0,0,0,0        ; temporary storage for a float
 
 ub2float	.proc
 		; -- convert ubyte in SCRATCH_ZPB1 to float at address A/Y
-		;    clobbers A, Y
-		stx  P8ZP_SCRATCH_REG
+		;    clobbers A, X, Y
 		sta  P8ZP_SCRATCH_W2
 		sty  P8ZP_SCRATCH_W2+1
 		ldy  P8ZP_SCRATCH_B1
@@ -19,15 +17,12 @@ ub2float	.proc
 		jsr  GIVAYF
 _fac_to_mem	ldx  P8ZP_SCRATCH_W2
 		ldy  P8ZP_SCRATCH_W2+1
-		jsr  MOVMF
-		ldx  P8ZP_SCRATCH_REG
-		rts
+		jmp  MOVMF
 		.pend
 
 b2float		.proc
 		; -- convert byte in SCRATCH_ZPB1 to float at address A/Y
-		;    clobbers A, Y
-		stx  P8ZP_SCRATCH_REG
+		;    clobbers A, X, Y
 		sta  P8ZP_SCRATCH_W2
 		sty  P8ZP_SCRATCH_W2+1
 		lda  P8ZP_SCRATCH_B1
@@ -37,7 +32,7 @@ b2float		.proc
 
 uw2float	.proc
 		; -- convert uword in SCRATCH_ZPWORD1 to float at address A/Y
-		stx  P8ZP_SCRATCH_REG
+		;    clobbers X
 		sta  P8ZP_SCRATCH_W2
 		sty  P8ZP_SCRATCH_W2+1
 		lda  P8ZP_SCRATCH_W1
@@ -48,7 +43,7 @@ uw2float	.proc
 
 w2float		.proc
 		; -- convert word in SCRATCH_ZPWORD1 to float at address A/Y
-		stx  P8ZP_SCRATCH_REG
+		;    clobbers X
 		sta  P8ZP_SCRATCH_W2
 		sty  P8ZP_SCRATCH_W2+1
 		ldy  P8ZP_SCRATCH_W1
@@ -60,7 +55,7 @@ w2float		.proc
 
 cast_from_uw	.proc
 		; -- uword in A/Y into float var at (P8ZP_SCRATCH_W2)
-		stx  P8ZP_SCRATCH_REG
+		;    clobbers X
 		jsr  GIVUAYFAY
 		jmp  ub2float._fac_to_mem
 		.pend
@@ -68,7 +63,7 @@ cast_from_uw	.proc
 
 cast_from_w	.proc
 		; -- word in A/Y into float var at (P8ZP_SCRATCH_W2)
-		stx  P8ZP_SCRATCH_REG
+		;    clobbers X
 		jsr  GIVAYFAY
 		jmp  ub2float._fac_to_mem
 		.pend
@@ -76,7 +71,7 @@ cast_from_w	.proc
 
 cast_from_ub	.proc
 		; -- ubyte in Y into float var at (P8ZP_SCRATCH_W2)
-		stx  P8ZP_SCRATCH_REG
+		;    clobbers X
 		jsr  FREADUY
 		jmp  ub2float._fac_to_mem
 		.pend
@@ -84,169 +79,41 @@ cast_from_ub	.proc
 
 cast_from_b	.proc
 		; -- byte in A into float var at (P8ZP_SCRATCH_W2)
-		stx  P8ZP_SCRATCH_REG
+		;    clobbers X
 		jsr  FREADSA
 		jmp  ub2float._fac_to_mem
 		.pend
 
 cast_as_uw_into_ya	.proc               ; also used for float 2 ub
 		; -- cast float at A/Y to uword into Y/A
+		;    clobbers X
 		jsr  MOVFM
 		jmp  cast_FAC1_as_uw_into_ya
 		.pend
 
 cast_as_w_into_ay	.proc               ; also used for float 2 b
 		; -- cast float at A/Y to word into A/Y
+		;    clobbers X
 		jsr  MOVFM
 		jmp  cast_FAC1_as_w_into_ay
 		.pend
 
 cast_FAC1_as_uw_into_ya	.proc               ; also used for float 2 ub
 		; -- cast fac1 to uword into Y/A
-		stx  P8ZP_SCRATCH_REG
-		jsr  GETADR     ; into Y/A
-		ldx  P8ZP_SCRATCH_REG
-		rts
+		;    clobbers X
+		jmp  GETADR     ; into Y/A
 		.pend
 
 cast_FAC1_as_w_into_ay	.proc               ; also used for float 2 b
 		; -- cast fac1 to word into A/Y
-		stx  P8ZP_SCRATCH_REG
+		;    clobbers X
 		jsr  AYINT
 		ldy  floats.AYINT_facmo
 		lda  floats.AYINT_facmo+1
-		ldx  P8ZP_SCRATCH_REG
 		rts
 		.pend
 
 
-stack_b2float	.proc
-		; -- b2float operating on the stack
-		inx
-		lda  P8ESTACK_LO,x
-		stx  P8ZP_SCRATCH_REG
-		jsr  FREADSA
-		jmp  push_fac1._internal
-		.pend
-
-stack_w2float	.proc
-		; -- w2float operating on the stack
-		inx
-		ldy  P8ESTACK_LO,x
-		lda  P8ESTACK_HI,x
-		stx  P8ZP_SCRATCH_REG
-		jsr  GIVAYF
-		jmp  push_fac1._internal
-		.pend
-
-stack_ub2float	.proc
-		; -- ub2float operating on the stack
-		inx
-		lda  P8ESTACK_LO,x
-		stx  P8ZP_SCRATCH_REG
-		tay
-		lda  #0
-		jsr  GIVAYF
-		jmp  push_fac1._internal
-		.pend
-
-stack_uw2float	.proc
-		; -- uw2float operating on the stack
-		inx
-		lda  P8ESTACK_LO,x
-		ldy  P8ESTACK_HI,x
-		stx  P8ZP_SCRATCH_REG
-		jsr  GIVUAYFAY
-		jmp  push_fac1._internal
-		.pend
-
-stack_float2w	.proc               ; also used for float2b
-		jsr  pop_float_fac1
-		stx  P8ZP_SCRATCH_REG
-		jsr  AYINT
-		ldx  P8ZP_SCRATCH_REG
-		lda  floats.AYINT_facmo
-		sta  P8ESTACK_HI,x
-		lda  floats.AYINT_facmo+1
-		sta  P8ESTACK_LO,x
-		dex
-		rts
-		.pend
-
-stack_float2uw	.proc               ; also used for float2ub
-		jsr  pop_float_fac1
-		stx  P8ZP_SCRATCH_REG
-		jsr  GETADR
-		ldx  P8ZP_SCRATCH_REG
-		sta  P8ESTACK_HI,x
-		tya
-		sta  P8ESTACK_LO,x
-		dex
-		rts
-		.pend
-
-push_float	.proc
-		; ---- push mflpt5 in A/Y onto stack
-		; (taking 3 stack positions = 6 bytes of which 1 is padding)
-		sta  P8ZP_SCRATCH_W1
-		sty  P8ZP_SCRATCH_W1+1
-		ldy  #0
-		lda  (P8ZP_SCRATCH_W1),y
-		sta  P8ESTACK_LO,x
-		iny
-		lda  (P8ZP_SCRATCH_W1),y
-		sta  P8ESTACK_HI,x
-		dex
-		iny
-		lda  (P8ZP_SCRATCH_W1),y
-		sta  P8ESTACK_LO,x
-		iny
-		lda  (P8ZP_SCRATCH_W1),y
-		sta  P8ESTACK_HI,x
-		dex
-		iny
-		lda  (P8ZP_SCRATCH_W1),y
-		sta  P8ESTACK_LO,x
-		dex
-		rts
-		.pend
-
-pop_float	.proc
-		; ---- pops mflpt5 from stack to memory A/Y
-		; (frees 3 stack positions = 6 bytes of which 1 is padding)
-		sta  P8ZP_SCRATCH_W1
-		sty  P8ZP_SCRATCH_W1+1
-		ldy  #4
-		inx
-		lda  P8ESTACK_LO,x
-		sta  (P8ZP_SCRATCH_W1),y
-		dey
-		inx
-		lda  P8ESTACK_HI,x
-		sta  (P8ZP_SCRATCH_W1),y
-		dey
-		lda  P8ESTACK_LO,x
-		sta  (P8ZP_SCRATCH_W1),y
-		dey
-		inx
-		lda  P8ESTACK_HI,x
-		sta  (P8ZP_SCRATCH_W1),y
-		dey
-		lda  P8ESTACK_LO,x
-		sta  (P8ZP_SCRATCH_W1),y
-		rts
-		.pend
-
-pop_float_fac1	.proc
-		; -- pops float from stack into FAC1
-		lda  #<fmath_float1
-		ldy  #>fmath_float1
-		jsr  pop_float
-		lda  #<fmath_float1
-		ldy  #>fmath_float1
-		jmp  MOVFM
-		.pend
-
 copy_float	.proc
 		; -- copies the 5 bytes of the mflt value pointed to by P8ZP_SCRATCH_W1,
 		;    into the 5 bytes pointed to by A/Y.  Clobbers A,Y.
@@ -272,25 +139,23 @@ copy_float	.proc
 
 inc_var_f	.proc
 		; -- add 1 to float pointed to by A/Y
+		;    clobbers X
 		sta  P8ZP_SCRATCH_W1
 		sty  P8ZP_SCRATCH_W1+1
-		stx  P8ZP_SCRATCH_REG
 		jsr  MOVFM
 		lda  #<FL_ONE_const
 		ldy  #>FL_ONE_const
 		jsr  FADD
 		ldx  P8ZP_SCRATCH_W1
 		ldy  P8ZP_SCRATCH_W1+1
-		jsr  MOVMF
-		ldx  P8ZP_SCRATCH_REG
-		rts
+		jmp  MOVMF
 		.pend
 
 dec_var_f	.proc
 		; -- subtract 1 from float pointed to by A/Y
+		;    clobbers X
 		sta  P8ZP_SCRATCH_W1
 		sty  P8ZP_SCRATCH_W1+1
-		stx  P8ZP_SCRATCH_REG
 		lda  #<FL_ONE_const
 		ldy  #>FL_ONE_const
 		jsr  MOVFM
@@ -299,23 +164,7 @@ dec_var_f	.proc
 		jsr  FSUB
 		ldx  P8ZP_SCRATCH_W1
 		ldy  P8ZP_SCRATCH_W1+1
-		jsr  MOVMF
-		ldx  P8ZP_SCRATCH_REG
-		rts
-		.pend
-
-
-pop_2_floats_f2_in_fac1	.proc
-		; -- pop 2 floats from stack, load the second one in FAC1 as well
-		lda  #<fmath_float2
-		ldy  #>fmath_float2
-		jsr  pop_float
-		lda  #<fmath_float1
-		ldy  #>fmath_float1
-		jsr  pop_float
-		lda  #<fmath_float2
-		ldy  #>fmath_float2
-		jmp  MOVFM
+		jmp  MOVMF
 		.pend
 
 
@@ -323,71 +172,9 @@ fmath_float1	.byte 0,0,0,0,0	; storage for a mflpt5 value
 fmath_float2	.byte 0,0,0,0,0	; storage for a mflpt5 value
 
 
-push_fac1	.proc
-		; -- push the float in FAC1 onto the stack
-		stx  P8ZP_SCRATCH_REG
-_internal	ldx  #<fmath_float1
-		ldy  #>fmath_float1
-		jsr  MOVMF
-		lda  #<fmath_float1
-		ldy  #>fmath_float1
-		ldx  P8ZP_SCRATCH_REG
-		jmp  push_float
-		.pend
-
-div_f		.proc
-		; -- push f1/f2 on stack
-		jsr  pop_2_floats_f2_in_fac1
-		stx  P8ZP_SCRATCH_REG
-		lda  #<fmath_float1
-		ldy  #>fmath_float1
-		jsr  FDIV
-		jmp  push_fac1._internal
-		.pend
-
-add_f		.proc
-		; -- push f1+f2 on stack
-		jsr  pop_2_floats_f2_in_fac1
-		stx  P8ZP_SCRATCH_REG
-		lda  #<fmath_float1
-		ldy  #>fmath_float1
-		jsr  FADD
-		jmp  push_fac1._internal
-		.pend
-
-sub_f		.proc
-		; -- push f1-f2 on stack
-		jsr  pop_2_floats_f2_in_fac1
-		stx  P8ZP_SCRATCH_REG
-		lda  #<fmath_float1
-		ldy  #>fmath_float1
-		jsr  FSUB
-		jmp  push_fac1._internal
-		.pend
-
-mul_f		.proc
-		; -- push f1*f2 on stack
-		jsr  pop_2_floats_f2_in_fac1
-		stx  P8ZP_SCRATCH_REG
-		lda  #<fmath_float1
-		ldy  #>fmath_float1
-		jsr  FMULT
-		jmp  push_fac1._internal
-		.pend
-
-neg_f		.proc
-		; -- toggle the sign bit on the stack
-		lda  P8ESTACK_HI+3,x
-		eor  #$80
-		sta  P8ESTACK_HI+3,x
-		rts
-		.pend
-
 var_fac1_less_f	.proc
-		; -- is the float in FAC1 < the variable AY?
-		stx  P8ZP_SCRATCH_REG
+		; -- is the float in FAC1 < the variable AY? Result in A. Clobbers X.
 		jsr  FCOMP
-		ldx  P8ZP_SCRATCH_REG
 		cmp  #255
 		beq  +
 		lda  #0
@@ -397,10 +184,8 @@ var_fac1_less_f	.proc
 		.pend
 
 var_fac1_lesseq_f	.proc
-		; -- is the float in FAC1 <= the variable AY?
-		stx  P8ZP_SCRATCH_REG
+		; -- is the float in FAC1 <= the variable AY?  Result in A. Clobbers X.
 		jsr  FCOMP
-		ldx  P8ZP_SCRATCH_REG
 		cmp  #0
 		beq  +
 		cmp  #255
@@ -412,10 +197,8 @@ var_fac1_lesseq_f	.proc
 		.pend
 
 var_fac1_greater_f	.proc
-		; -- is the float in FAC1 > the variable AY?
-		stx  P8ZP_SCRATCH_REG
+		; -- is the float in FAC1 > the variable AY?  Result in A. Clobbers X.
 		jsr  FCOMP
-		ldx  P8ZP_SCRATCH_REG
 		cmp  #1
 		beq  +
 		lda  #0
@@ -425,10 +208,8 @@ var_fac1_greater_f	.proc
 		.pend
 
 var_fac1_greatereq_f	.proc
-		; -- is the float in FAC1 >= the variable AY?
-		stx  P8ZP_SCRATCH_REG
+		; -- is the float in FAC1 >= the variable AY?  Result in A. Clobbers X.
 		jsr  FCOMP
-		ldx  P8ZP_SCRATCH_REG
 		cmp  #0
 		beq  +
 		cmp  #1
@@ -439,17 +220,23 @@ var_fac1_greatereq_f	.proc
 		rts
 		.pend
 
+var_fac1_equal_f	.proc
+		; -- are the floats numbers in FAC1 and the variable AY *not* identical?   Result in A. Clobbers X.
+		jsr  FCOMP
+		and  #1
+		eor  #1
+		rts
+		.pend
+
 var_fac1_notequal_f	.proc
-		; -- are the floats numbers in FAC1 and the variable AY *not* identical?
-		stx  P8ZP_SCRATCH_REG
+		; -- are the floats numbers in FAC1 and the variable AY *not* identical?   Result in A. Clobbers X.
 		jsr  FCOMP
-		ldx  P8ZP_SCRATCH_REG
 		and  #1
 		rts
 		.pend
 
 vars_equal_f	.proc
-		; -- are the mflpt5 numbers in P8ZP_SCRATCH_W1 and AY identical?
+		; -- are the mflpt5 numbers in P8ZP_SCRATCH_W1 and AY identical?  Result in A
 		sta  P8ZP_SCRATCH_W2
 		sty  P8ZP_SCRATCH_W2+1
 		ldy  #0
@@ -478,51 +265,13 @@ _false		lda  #0
 		rts
 		.pend
 
-equal_f		.proc
-		; -- are the two mflpt5 numbers on the stack identical?
-		inx
-		inx
-		inx
-		inx
-		lda  P8ESTACK_LO-3,x
-		cmp  P8ESTACK_LO,x
-		bne  _equals_false
-		lda  P8ESTACK_LO-2,x
-		cmp  P8ESTACK_LO+1,x
-		bne  _equals_false
-		lda  P8ESTACK_LO-1,x
-		cmp  P8ESTACK_LO+2,x
-		bne  _equals_false
-		lda  P8ESTACK_HI-2,x
-		cmp  P8ESTACK_HI+1,x
-		bne  _equals_false
-		lda  P8ESTACK_HI-1,x
-		cmp  P8ESTACK_HI+2,x
-		bne  _equals_false
-_equals_true	lda  #1
-_equals_store	inx
-		sta  P8ESTACK_LO+1,x
-		rts
-_equals_false	lda  #0
-		beq  _equals_store
-		.pend
-
-notequal_f	.proc
-		; -- are the two mflpt5 numbers on the stack different?
-		jsr  equal_f
-		eor  #1		; invert the result
-		sta  P8ESTACK_LO+1,x
-		rts
-		.pend
 
 vars_less_f	.proc
-		; -- is float in AY < float in P8ZP_SCRATCH_W2 ?
+		; -- is float in AY < float in P8ZP_SCRATCH_W2 ?   Result in A. Clobbers X.
 		jsr  MOVFM
 		lda  P8ZP_SCRATCH_W2
 		ldy  P8ZP_SCRATCH_W2+1
-		stx  P8ZP_SCRATCH_REG
 		jsr  FCOMP
-		ldx  P8ZP_SCRATCH_REG
 		cmp  #255
 		bne  +
 		lda  #1
@@ -532,13 +281,11 @@ vars_less_f	.proc
 		.pend
 
 vars_lesseq_f	.proc
-		; -- is float in AY <= float in P8ZP_SCRATCH_W2 ?
+		; -- is float in AY <= float in P8ZP_SCRATCH_W2 ?  Result in A. Clobbers X.
 		jsr  MOVFM
 		lda  P8ZP_SCRATCH_W2
 		ldy  P8ZP_SCRATCH_W2+1
-		stx  P8ZP_SCRATCH_REG
 		jsr  FCOMP
-		ldx  P8ZP_SCRATCH_REG
 		cmp  #255
 		bne  +
 -		lda  #1
@@ -550,7 +297,7 @@ vars_lesseq_f	.proc
 		.pend
 
 less_f		.proc
-		; -- is f1 < f2?
+		; -- is f1 < f2?    Result in A. Clobbers X.
 		jsr  compare_floats
 		cmp  #255
 		beq  compare_floats._return_true
@@ -559,7 +306,7 @@ less_f		.proc
 
 
 lesseq_f	.proc
-		; -- is f1 <= f2?
+		; -- is f1 <= f2?  Result in A. Clobbers X.
 		jsr  compare_floats
 		cmp  #255
 		beq  compare_floats._return_true
@@ -569,7 +316,7 @@ lesseq_f	.proc
 		.pend
 
 greater_f	.proc
-		; -- is f1 > f2?
+		; -- is f1 > f2?  Result in A. Clobbers X.
 		jsr  compare_floats
 		cmp  #1
 		beq  compare_floats._return_true
@@ -577,7 +324,7 @@ greater_f	.proc
 		.pend
 
 greatereq_f	.proc
-		; -- is f1 >= f2?
+		; -- is f1 >= f2?  Result in A. Clobbers X.
 		jsr  compare_floats
 		cmp  #1
 		beq  compare_floats._return_true
@@ -586,32 +333,9 @@ greatereq_f	.proc
 		bne  compare_floats._return_false
 		.pend
 
-compare_floats	.proc
-		lda  #<fmath_float2
-		ldy  #>fmath_float2
-		jsr  pop_float
-		lda  #<fmath_float1
-		ldy  #>fmath_float1
-		jsr  pop_float
-		lda  #<fmath_float1
-		ldy  #>fmath_float1
-		jsr  MOVFM		; fac1 = flt1
-		lda  #<fmath_float2
-		ldy  #>fmath_float2
-		stx  P8ZP_SCRATCH_REG
-		jsr  FCOMP		; A = flt1 compared with flt2 (0=equal, 1=flt1>flt2, 255=flt1<flt2)
-		ldx  P8ZP_SCRATCH_REG
-		rts
-_return_false	lda  #0
-_return_result  sta  P8ESTACK_LO,x
-		dex
-		rts
-_return_true	lda  #1
-		bne  _return_result
-		.pend
-
 set_array_float_from_fac1	.proc
 		; -- set the float in FAC1 in the array (index in A, array in P8ZP_SCRATCH_W1)
+		;    clobbers X
 		sta  P8ZP_SCRATCH_B1
 		asl  a
 		asl  a
@@ -622,11 +346,8 @@ set_array_float_from_fac1	.proc
 		adc  P8ZP_SCRATCH_W1
 		bcc  +
 		iny
-+		stx  floats_store_reg
-		tax
-		jsr  MOVMF
-		ldx  floats_store_reg
-		rts
++		tax
+		jmp  MOVMF
 		.pend
 
 
@@ -669,54 +390,63 @@ set_array_float		.proc
 		.pend
 
 
-equal_zero	.proc
-		jsr  floats.pop_float_fac1
-		jsr  floats.SIGN
-		beq  _true
-		bne  _false
-_true		lda  #1
-		sta  P8ESTACK_LO,x
-		dex
-		rts
-_false		lda  #0
-		sta  P8ESTACK_LO,x
-		dex
-		rts
-		.pend
+pushFAC1    .proc
+	;-- push floating point in FAC onto the cpu stack
+	; save return address
+	pla
+	sta  P8ZP_SCRATCH_W2
+	pla
+	sta  P8ZP_SCRATCH_W2+1
+	ldx  #<floats.floats_temp_var
+	ldy  #>floats.floats_temp_var
+	jsr  floats.MOVMF
+	lda  floats.floats_temp_var
+	pha
+	lda  floats.floats_temp_var+1
+	pha
+	lda  floats.floats_temp_var+2
+	pha
+	lda  floats.floats_temp_var+3
+	pha
+	lda  floats.floats_temp_var+4
+	pha
+	; re-push return address
+	lda  P8ZP_SCRATCH_W2+1
+	pha
+	lda  P8ZP_SCRATCH_W2
+	pha
+	rts
+	.pend
 
-notequal_zero	.proc
-		jsr  floats.pop_float_fac1
-		jsr  floats.SIGN
-		bne  equal_zero._true
-		beq  equal_zero._false
-		.pend
+popFAC .proc
+	; -- pop floating point value from cpu stack into FAC1 or FAC2 (
+	;    carry flag clear=FAC1, carry set=FAC2
+	; save return address
+	pla
+	sta  P8ZP_SCRATCH_W2
+	pla
+	sta  P8ZP_SCRATCH_W2+1
+	pla
+	sta  floats.floats_temp_var+4
+	pla
+	sta  floats.floats_temp_var+3
+	pla
+	sta  floats.floats_temp_var+2
+	pla
+	sta  floats.floats_temp_var+1
+	pla
+	sta  floats.floats_temp_var
+	lda  #<floats.floats_temp_var
+	ldy  #>floats.floats_temp_var
+	bcs  +
+	jsr  floats.MOVFM
+	jmp  ++
++       jsr  floats.CONUPK
++	; re-push return address
+	lda  P8ZP_SCRATCH_W2+1
+	pha
+	lda  P8ZP_SCRATCH_W2
+	pha
+	rts
+	.pend
 
-greater_zero	.proc
-		jsr  floats.pop_float_fac1
-		jsr  floats.SIGN
-		beq  equal_zero._false
-		bpl  equal_zero._true
-		jmp  equal_zero._false
-		.pend
-
-less_zero	.proc
-		jsr  floats.pop_float_fac1
-		jsr  floats.SIGN
-		bmi  equal_zero._true
-		jmp  equal_zero._false
-		.pend
-
-greaterequal_zero	.proc
-		jsr  floats.pop_float_fac1
-		jsr  floats.SIGN
-		bpl  equal_zero._true
-		jmp  equal_zero._false
-		.pend
-
-lessequal_zero	.proc
-		jsr  floats.pop_float_fac1
-		jsr  floats.SIGN
-		beq  equal_zero._true
-		bmi  equal_zero._true
-		jmp  equal_zero._false
-		.pend