avoid costly multiplications to get indexed pointer address

(found 2 regressions that still need to be handled)

.gitignore

@@ -7,10 +7,13 @@ build/
 dist/
 output/
 out/
+out-new/
+out-old/
 .*cache/
 *.directory
 *.prg
 *.bin
+*.p8ir
 *.labels.txt
 *.vm.txt
 *.vice-mon-list

.idea/kotlinc.xml

@@ -7,13 +7,13 @@
     <option name="jvmTarget" value="11" />
   </component>
   <component name="KotlinCommonCompilerArguments">
-    <option name="apiVersion" value="2.1" />
-    <option name="languageVersion" value="2.1" />
+    <option name="apiVersion" value="2.2" />
+    <option name="languageVersion" value="2.2" />
   </component>
   <component name="KotlinCompilerSettings">
-    <option name="additionalArguments" value="-Xwhen-guards" />
+    <option name="additionalArguments" value="-Xwhen-guards -jvm-default=no-compatibility" />
   </component>
   <component name="KotlinJpsPluginSettings">
-    <option name="version" value="2.1.10" />
+    <option name="version" value="2.2.0" />
   </component>
 </project>

.idea/libraries/KotlinJavaRuntime.xml

@@ -1,23 +1,23 @@
 <component name="libraryTable">
   <library name="KotlinJavaRuntime" type="repository">
-    <properties maven-id="org.jetbrains.kotlin:kotlin-stdlib-jdk8:2.1.20" />
+    <properties maven-id="org.jetbrains.kotlin:kotlin-stdlib-jdk8:2.2.10" />
     <CLASSES>
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk8/2.1.20/kotlin-stdlib-jdk8-2.1.20.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/2.1.20/kotlin-stdlib-2.1.20.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk8/2.2.10/kotlin-stdlib-jdk8-2.2.10.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/2.2.10/kotlin-stdlib-2.2.10.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/annotations/13.0/annotations-13.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk7/2.1.20/kotlin-stdlib-jdk7-2.1.20.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk7/2.2.10/kotlin-stdlib-jdk7-2.2.10.jar!/" />
     </CLASSES>
     <JAVADOC>
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk8/2.1.20/kotlin-stdlib-jdk8-2.1.20-javadoc.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/2.1.20/kotlin-stdlib-2.1.20-javadoc.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk8/2.2.10/kotlin-stdlib-jdk8-2.2.10-javadoc.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/2.2.10/kotlin-stdlib-2.2.10-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-jdk7/2.1.20/kotlin-stdlib-jdk7-2.1.20-javadoc.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk7/2.2.10/kotlin-stdlib-jdk7-2.2.10-javadoc.jar!/" />
     </JAVADOC>
     <SOURCES>
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk8/2.1.20/kotlin-stdlib-jdk8-2.1.20-sources.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/2.1.20/kotlin-stdlib-2.1.20-sources.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk8/2.2.10/kotlin-stdlib-jdk8-2.2.10-sources.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/2.2.10/kotlin-stdlib-2.2.10-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-jdk7/2.1.20/kotlin-stdlib-jdk7-2.1.20-sources.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib-jdk7/2.2.10/kotlin-stdlib-jdk7-2.2.10-sources.jar!/" />
     </SOURCES>
   </library>
 </component>

.idea/libraries/eclipse_lsp4j.xml

@@ -4,8 +4,8 @@
     <CLASSES>
       <root url="jar://$MAVEN_REPOSITORY$/org/eclipse/lsp4j/org.eclipse.lsp4j/0.24.0/org.eclipse.lsp4j-0.24.0.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/eclipse/lsp4j/org.eclipse.lsp4j.jsonrpc/0.24.0/org.eclipse.lsp4j.jsonrpc-0.24.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/com/google/code/gson/gson/2.12.1/gson-2.12.1.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/com/google/errorprone/error_prone_annotations/2.36.0/error_prone_annotations-2.36.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/com/google/code/gson/gson/2.13.1/gson-2.13.1.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/com/google/errorprone/error_prone_annotations/2.38.0/error_prone_annotations-2.38.0.jar!/" />
     </CLASSES>
     <JAVADOC />
     <SOURCES />

.idea/libraries/io_kotest_assertions_core_jvm.xml

@@ -1,20 +0,0 @@
-<component name="libraryTable">
-  <library name="io.kotest.assertions.core.jvm" type="repository">
-    <properties maven-id="io.kotest:kotest-assertions-core-jvm:5.9.1" />
-    <CLASSES>
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-core-jvm/5.9.1/kotest-assertions-core-jvm-5.9.1.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-shared-jvm/5.9.1/kotest-assertions-shared-jvm-5.9.1.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/1.3.0/opentest4j-1.3.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/1.9.23/kotlin-stdlib-1.9.23.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/annotations/13.0/annotations-13.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-jdk8/1.8.0/kotlinx-coroutines-jdk8-1.8.0.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-reflect/1.9.23/kotlin-reflect-1.9.23.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-common-jvm/5.9.1/kotest-common-jvm-5.9.1.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/io/kotest/kotest-assertions-api-jvm/5.9.1/kotest-assertions-api-jvm-5.9.1.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlinx/kotlinx-coroutines-core-jvm/1.8.0/kotlinx-coroutines-core-jvm-1.8.0.jar!/" />
-    </CLASSES>
-    <JAVADOC />
-    <SOURCES />
-  </library>
-</component>

.idea/libraries/michael_bull_kotlin_result_jvm.xml

@@ -1,19 +1,19 @@
 <component name="libraryTable">
   <library name="michael.bull.kotlin.result.jvm" type="repository">
-    <properties maven-id="com.michael-bull.kotlin-result:kotlin-result-jvm:2.0.1" />
+    <properties maven-id="com.michael-bull.kotlin-result:kotlin-result-jvm:2.1.0" />
     <CLASSES>
-      <root url="jar://$MAVEN_REPOSITORY$/com/michael-bull/kotlin-result/kotlin-result-jvm/2.0.1/kotlin-result-jvm-2.0.1.jar!/" />
-      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/1.9.22/kotlin-stdlib-1.9.22.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/com/michael-bull/kotlin-result/kotlin-result-jvm/2.1.0/kotlin-result-jvm-2.1.0.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/2.2.0/kotlin-stdlib-2.2.0.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/annotations/13.0/annotations-13.0.jar!/" />
     </CLASSES>
     <JAVADOC>
-      <root url="jar://$MAVEN_REPOSITORY$/com/michael-bull/kotlin-result/kotlin-result-jvm/2.0.1/kotlin-result-jvm-2.0.1-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://$MAVEN_REPOSITORY$/com/michael-bull/kotlin-result/kotlin-result-jvm/2.1.0/kotlin-result-jvm-2.1.0-javadoc.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/2.2.0/kotlin-stdlib-2.2.0-javadoc.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/annotations/13.0/annotations-13.0-javadoc.jar!/" />
     </JAVADOC>
     <SOURCES>
-      <root url="jar://$MAVEN_REPOSITORY$/com/michael-bull/kotlin-result/kotlin-result-jvm/2.0.1/kotlin-result-jvm-2.0.1-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://$MAVEN_REPOSITORY$/com/michael-bull/kotlin-result/kotlin-result-jvm/2.1.0/kotlin-result-jvm-2.1.0-sources.jar!/" />
+      <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/kotlin/kotlin-stdlib/2.2.0/kotlin-stdlib-2.2.0-sources.jar!/" />
       <root url="jar://$MAVEN_REPOSITORY$/org/jetbrains/annotations/13.0/annotations-13.0-sources.jar!/" />
     </SOURCES>
   </library>

.idea/misc.xml

@@ -12,6 +12,7 @@
           <option name="pkg" value="" />
           <option name="language" value="Java" />
           <option name="generateListener" value="false" />
+          <option name="generateVisitor" value="true" />
         </PerGrammarGenerationSettings>
       </list>
     </option>
@@ -25,4 +26,7 @@
   <component name="ProjectRootManager" version="2" languageLevel="JDK_21" default="true" project-jdk-name="openjdk-21" project-jdk-type="JavaSDK">
     <output url="file://$PROJECT_DIR$/out" />
   </component>
+  <component name="PythonCompatibilityInspectionAdvertiser">
+    <option name="version" value="3" />
+  </component>
 </project>

README.md

@@ -61,6 +61,7 @@ What does Prog8 provide?
 - code often is smaller and faster than equivalent C code compiled with CC65 or even LLVM-MOS
 - modularity, symbol scoping, subroutines. No need for forward declarations.
 - various data types other than just bytes (16-bit words, floats, strings)
+- Structs and typed pointers
 - floating point math is supported on certain targets
 - access to most Kernal ROM routines as external subroutine definitions you can call normally
 - tight control over Zeropage usage
@@ -71,6 +72,7 @@ What does Prog8 provide?
 - high-level program optimizations
 - conditional branches that map 1:1 to cpu status flags
 - ``when`` statement to provide a concise jump table alternative to if/elseif chains
+- ``on .. goto`` statement for fast jump tables
 - ``in`` expression for concise and efficient multi-value/containment check 
 - ``defer`` statement to help write concise and robust subroutine cleanup logic
 - several specialized built-in functions such as ``lsb``, ``msb``, ``min``, ``max``, ``rol``, ``ror``
@@ -95,7 +97,7 @@ What does Prog8 provide?
 - "c64": Commodore-64  (6502 like CPU)
 - "c128": Commodore-128  (6502 like CPU - the Z80 cpu mode is not supported)
 - "pet32": Commodore PET (limited support)
-- via external configurable targets: Atari 800 XL, Neo6502, NES, C64OS, ...
+- via external configurable targets: Atari 800 XL, Neo6502, NES, C64 OS, Foenix F256, ...
 - If you only use standard kernal and prog8 library routines, it is possible to compile the *exact same program* for different machines (just change the compiler target flag)
 
 

build.gradle.kts

@@ -1,9 +1,10 @@
 import org.jetbrains.kotlin.gradle.dsl.JvmTarget
+import org.jetbrains.kotlin.gradle.dsl.JvmDefaultMode
 import org.jetbrains.kotlin.gradle.internal.config.LanguageFeature
 
 
 plugins {
-    kotlin("jvm") version "2.1.20"
+    kotlin("jvm") version "2.2.10"
 }
 
 allprojects {
@@ -18,6 +19,7 @@ allprojects {
         compilerOptions {
             freeCompilerArgs = listOf("-Xwhen-guards")
             jvmTarget = JvmTarget.JVM_11
+            jvmDefault = JvmDefaultMode.NO_COMPATIBILITY
         }
         sourceSets.all {
             languageSettings {

codeCore/build.gradle.kts

@@ -1,5 +1,3 @@
-import org.jetbrains.kotlin.gradle.dsl.JvmTarget
-
 plugins {
     kotlin("jvm")
 }
@@ -7,7 +5,7 @@ plugins {
 dependencies {
     // should have no dependencies to other modules
     // implementation("org.jetbrains.kotlin:kotlin-stdlib-jdk8")
-    implementation("com.michael-bull.kotlin-result:kotlin-result-jvm:2.0.1")
+    implementation("com.michael-bull.kotlin-result:kotlin-result-jvm:2.1.0")
 }
 
 sourceSets {

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

@@ -96,12 +96,13 @@ val BuiltinFunctions: Map<String, FSignature> = mapOf(
     "prog8_lib_stringcompare"     to FSignature(true, BaseDataType.BYTE, FParam("str1", BaseDataType.STR), FParam("str2", BaseDataType.STR)),
     "prog8_lib_square_byte"       to FSignature(true, BaseDataType.UBYTE, FParam("value", BaseDataType.BYTE, BaseDataType.UBYTE)),
     "prog8_lib_square_word"       to FSignature(true, BaseDataType.UWORD, FParam("value", BaseDataType.WORD, BaseDataType.UWORD)),
+    "prog8_lib_structalloc"       to FSignature(true, BaseDataType.UWORD),
     "abs"           to FSignature(true, null, FParam("value", *NumericDatatypes)),
     "abs__byte"     to FSignature(true, BaseDataType.UBYTE, FParam("value", BaseDataType.BYTE)),
     "abs__word"     to FSignature(true, BaseDataType.UWORD, FParam("value", BaseDataType.WORD)),
     "abs__float"    to FSignature(true, BaseDataType.FLOAT, FParam("value", BaseDataType.FLOAT)),
     "len"           to FSignature(true, BaseDataType.UWORD, FParam("values", *IterableDatatypes)),
-    "sizeof"        to FSignature(true, BaseDataType.UBYTE, FParam("object", *BaseDataType.entries.toTypedArray())),
+    "sizeof"        to FSignature(true, BaseDataType.UBYTE, FParam("object", *(BaseDataType.entries - BaseDataType.STRUCT_INSTANCE).toTypedArray())),
     "sgn"           to FSignature(true, BaseDataType.BYTE, FParam("value", *NumericDatatypes)),
     "sqrt"          to FSignature(true, null, FParam("value", *NumericDatatypes)),
     "sqrt__ubyte"   to FSignature(true, BaseDataType.UBYTE, FParam("value", BaseDataType.UBYTE)),
@@ -131,10 +132,15 @@ val BuiltinFunctions: Map<String, FSignature> = mapOf(
     "max__word"     to FSignature(true, BaseDataType.WORD, FParam("val1", BaseDataType.WORD), FParam("val2", BaseDataType.WORD)),
     "max__uword"    to FSignature(true, BaseDataType.UWORD, FParam("val1", BaseDataType.UWORD), FParam("val2", BaseDataType.UWORD)),
     "peek"          to FSignature(true, BaseDataType.UBYTE, FParam("address", BaseDataType.UWORD)),
+    "peekbool"      to FSignature(true, BaseDataType.BOOL, FParam("address", BaseDataType.UWORD)),
     "peekw"         to FSignature(true, BaseDataType.UWORD, FParam("address", BaseDataType.UWORD)),
+    "peekl"         to FSignature(true, BaseDataType.LONG, FParam("address", BaseDataType.UWORD)),
     "peekf"         to FSignature(true, BaseDataType.FLOAT, FParam("address", BaseDataType.UWORD)),
     "poke"          to FSignature(false, null, FParam("address", BaseDataType.UWORD), FParam("value", BaseDataType.UBYTE)),
+    "pokebool"      to FSignature(false, null, FParam("address", BaseDataType.UWORD), FParam("value", BaseDataType.BOOL)),
+    "pokebowl"      to FSignature(false, null, FParam("address", BaseDataType.UWORD), FParam("value", BaseDataType.BOOL)),
     "pokew"         to FSignature(false, null, FParam("address", BaseDataType.UWORD), FParam("value", BaseDataType.UWORD)),
+    "pokel"         to FSignature(false, null, FParam("address", BaseDataType.UWORD), FParam("value", BaseDataType.LONG)),
     "pokef"         to FSignature(false, null, FParam("address", BaseDataType.UWORD), FParam("value", BaseDataType.FLOAT)),
     "pokemon"       to FSignature(false, BaseDataType.UBYTE, FParam("address", BaseDataType.UWORD), FParam("value", BaseDataType.UBYTE)),
     "rsave"         to FSignature(false, null),

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

@@ -13,6 +13,9 @@ enum class BaseDataType {
     STR,                // pass by reference
     ARRAY,              // pass by reference, subtype is the element type
     ARRAY_SPLITW,       // pass by reference, split word layout, subtype is the element type (restricted to word types)
+    POINTER,            // typed pointer, subtype is whatever type is pointed to
+    STRUCT_INSTANCE,    // the actual instance of a struct (not directly supported in the language yet, but we need its type)
+    ARRAY_POINTER,      // array of pointers (uwords), subtype is whatever type each element points to
     UNDEFINED;
 
 
@@ -26,6 +29,7 @@ enum class BaseDataType {
             this.isArray && other.isArray -> false
             this.isArray -> other != FLOAT
             this == STR -> other != FLOAT
+            this.isPointer -> other.isByteOrBool
             else -> true
         }
 
@@ -34,7 +38,8 @@ enum class BaseDataType {
             this == other -> true
             this.isArray && other.isArray -> true
             this.isByteOrBool -> other.isByteOrBool
-            this.isWord -> other.isWord
+            this.isWord -> other.isWord || other.isPointer
+            this.isPointer -> other.isWord
             this == STR && other== UWORD || this== UWORD && other== STR -> true
             this == STR && other.isArray -> true
             this.isArray && other == STR -> true
@@ -50,84 +55,163 @@ val BaseDataType.isIntegerOrBool get() = this in arrayOf(BaseDataType.UBYTE, Bas
 val BaseDataType.isNumeric get() = this == BaseDataType.FLOAT || this.isInteger
 val BaseDataType.isNumericOrBool get() = this == BaseDataType.BOOL || this.isNumeric
 val BaseDataType.isSigned get() = this in arrayOf(BaseDataType.BYTE, BaseDataType.WORD, BaseDataType.LONG, BaseDataType.FLOAT)
-val BaseDataType.isArray get() = this == BaseDataType.ARRAY || this == BaseDataType.ARRAY_SPLITW
-val BaseDataType.isSplitWordArray get() = this == BaseDataType.ARRAY_SPLITW
-val BaseDataType.isIterable get() =  this in arrayOf(BaseDataType.STR, BaseDataType.ARRAY, BaseDataType.ARRAY_SPLITW)
-val BaseDataType.isPassByRef get() = this.isIterable
-val BaseDataType.isPassByValue get() = !this.isIterable
+val BaseDataType.isArray get() = this == BaseDataType.ARRAY || this == BaseDataType.ARRAY_SPLITW || this == BaseDataType.ARRAY_POINTER
+val BaseDataType.isPointer get() = this == BaseDataType.POINTER
+val BaseDataType.isStructInstance get() = this == BaseDataType.STRUCT_INSTANCE
+val BaseDataType.isPointerArray get() = this == BaseDataType.ARRAY_POINTER
+val BaseDataType.isSplitWordArray get() = this == BaseDataType.ARRAY_SPLITW || this == BaseDataType.ARRAY_POINTER       // pointer arrays are also always stored as split uwords
+val BaseDataType.isIterable get() =  this in arrayOf(BaseDataType.STR, BaseDataType.ARRAY, BaseDataType.ARRAY_SPLITW, BaseDataType.ARRAY_POINTER)
+val BaseDataType.isPassByRef get() = this.isIterable && !this.isPointer
+val BaseDataType.isPassByValue get() = !this.isIterable || this.isPointer
 
 
-class DataType private constructor(val base: BaseDataType, val sub: BaseDataType?) {
+interface ISubType {
+    val scopedNameString: String
+    fun memsize(sizer: IMemSizer): Int
+    fun sameas(other: ISubType): Boolean
+    fun getFieldType(name: String): DataType?
+}
+
+class DataType private constructor(val base: BaseDataType, val sub: BaseDataType?, var subType: ISubType?, var subTypeFromAntlr: List<String>?=null) {
 
     init {
-        if(base.isArray) {
-            require(sub != null)
-            if(base.isSplitWordArray)
-                require(sub == BaseDataType.UWORD || sub == BaseDataType.WORD)
+        when {
+            base.isPointerArray -> {
+                require(sub!=null || subType!=null || subTypeFromAntlr!=null)
+            }
+            base.isArray -> {
+                require(sub != null && subType==null && subTypeFromAntlr==null)
+                if(base.isSplitWordArray)
+                    require(sub == BaseDataType.UWORD || sub == BaseDataType.WORD)
+            }
+            base==BaseDataType.STR -> require(sub==BaseDataType.UBYTE) { "string subtype should be ubyte" }
+            base!=BaseDataType.POINTER -> require(sub == null) { "only string, array and pointer base types can have a subtype"}
+            else -> {
+                require(sub == null || (subType == null && subTypeFromAntlr == null)) {
+                    "sub and subtype can't both be set"
+                }
+            }
         }
-        else if(base==BaseDataType.STR)
-            require(sub==BaseDataType.UBYTE) { "string subtype should be ubyte" }
-        else
-            require(sub == null) { "only string and array base types can have a subtype"}
     }
 
     override fun equals(other: Any?): Boolean {
         if (this === other) return true
         if (other !is DataType) return false
-        return base == other.base && sub == other.sub
+        return base == other.base && sub == other.sub && (subType==other.subType || subType!!.sameas(other.subType!!))
     }
 
-    override fun hashCode(): Int = Objects.hash(base, sub)
+    override fun hashCode(): Int = Objects.hash(base, sub, subType)
+
+    fun setActualSubType(actualSubType: ISubType) {
+        subType = actualSubType
+        subTypeFromAntlr = null
+    }
 
     companion object {
 
-        val UBYTE = DataType(BaseDataType.UBYTE, null)
-        val BYTE = DataType(BaseDataType.BYTE, null)
-        val UWORD = DataType(BaseDataType.UWORD, null)
-        val WORD = DataType(BaseDataType.WORD, null)
-        val LONG = DataType(BaseDataType.LONG, null)
-        val FLOAT = DataType(BaseDataType.FLOAT, null)
-        val BOOL = DataType(BaseDataType.BOOL, null)
-        val STR = DataType(BaseDataType.STR, BaseDataType.UBYTE)
-        val UNDEFINED = DataType(BaseDataType.UNDEFINED, null)
+        val UBYTE = DataType(BaseDataType.UBYTE, null, null)
+        val BYTE = DataType(BaseDataType.BYTE, null, null)
+        val UWORD = DataType(BaseDataType.UWORD, null, null)
+        val WORD = DataType(BaseDataType.WORD, null, null)
+        val LONG = DataType(BaseDataType.LONG, null, null)
+        val FLOAT = DataType(BaseDataType.FLOAT, null, null)
+        val BOOL = DataType(BaseDataType.BOOL, null, null)
+        val STR = DataType(BaseDataType.STR, BaseDataType.UBYTE, null)
+        val UNDEFINED = DataType(BaseDataType.UNDEFINED, null, null)
 
         private val simpletypes = mapOf(
-            BaseDataType.UBYTE to DataType(BaseDataType.UBYTE, null),
-            BaseDataType.BYTE to DataType(BaseDataType.BYTE, null),
-            BaseDataType.UWORD to DataType(BaseDataType.UWORD, null),
-            BaseDataType.WORD to DataType(BaseDataType.WORD, null),
-            BaseDataType.LONG to DataType(BaseDataType.LONG, null),
-            BaseDataType.FLOAT to DataType(BaseDataType.FLOAT, null),
-            BaseDataType.BOOL to DataType(BaseDataType.BOOL, null),
-            BaseDataType.STR to DataType(BaseDataType.STR, BaseDataType.UBYTE),
-            BaseDataType.UNDEFINED to DataType(BaseDataType.UNDEFINED, null)
+            BaseDataType.UBYTE to DataType(BaseDataType.UBYTE, null, null),
+            BaseDataType.BYTE to DataType(BaseDataType.BYTE, null, null),
+            BaseDataType.UWORD to DataType(BaseDataType.UWORD, null, null),
+            BaseDataType.WORD to DataType(BaseDataType.WORD, null, null),
+            BaseDataType.LONG to DataType(BaseDataType.LONG, null, null),
+            BaseDataType.FLOAT to DataType(BaseDataType.FLOAT, null, null),
+            BaseDataType.BOOL to DataType(BaseDataType.BOOL, null, null),
+            BaseDataType.STR to DataType(BaseDataType.STR, BaseDataType.UBYTE, null),
+            BaseDataType.UNDEFINED to DataType(BaseDataType.UNDEFINED, null, null)
         )
 
-        fun forDt(dt: BaseDataType) = simpletypes.getValue(dt)
+        fun forDt(dt: BaseDataType): DataType {
+            if(dt.isStructInstance)
+                TODO("cannot use struct instance as a data type (yet) - use a pointer instead")
+            return simpletypes.getValue(dt)
+        }
 
         fun arrayFor(elementDt: BaseDataType, splitwordarray: Boolean=true): DataType {
+            require(!elementDt.isPointer) { "use other array constructor for arrays of pointers" }
             val actualElementDt = if(elementDt==BaseDataType.STR) BaseDataType.UWORD else elementDt      // array of strings is actually just an array of UWORD pointers
             return if(splitwordarray && actualElementDt.isWord)
-                DataType(BaseDataType.ARRAY_SPLITW, actualElementDt)
+                DataType(BaseDataType.ARRAY_SPLITW, actualElementDt, null)
             else {
                 if(actualElementDt.isNumericOrBool && actualElementDt != BaseDataType.LONG)
-                    DataType(BaseDataType.ARRAY, actualElementDt)
+                    DataType(BaseDataType.ARRAY, actualElementDt, null)
                 else
-                    throw NoSuchElementException("invalid element dt $elementDt")
+                    throw NoSuchElementException("invalid basic element dt $elementDt")
             }
         }
+
+        fun arrayOfPointersTo(sub: BaseDataType): DataType = DataType(BaseDataType.ARRAY_POINTER, sub, null)
+        fun arrayOfPointersTo(structType: ISubType?): DataType = DataType(BaseDataType.ARRAY_POINTER, null, structType)
+        fun arrayOfPointersFromAntlrTo(sub: BaseDataType?, identifier: List<String>?): DataType =
+            DataType(BaseDataType.ARRAY_POINTER, sub, null, identifier)
+
+        fun pointer(base: BaseDataType): DataType = DataType(BaseDataType.POINTER, base, null)
+        fun pointer(dt: DataType): DataType = if(dt.isBasic)
+                DataType(BaseDataType.POINTER, dt.base, null)
+            else
+                DataType(BaseDataType.POINTER, null, dt.subType, dt.subTypeFromAntlr)
+        fun pointer(structType: ISubType): DataType = DataType(BaseDataType.POINTER, null, structType)
+        fun pointerFromAntlr(identifier: List<String>): DataType = DataType(BaseDataType.POINTER, null, null, identifier)
+        fun structInstance(type: ISubType?): DataType = DataType(BaseDataType.STRUCT_INSTANCE, sub=null, type)
+        fun structInstanceFromAntlr(struct: List<String>): DataType = DataType(BaseDataType.STRUCT_INSTANCE, null, null, subTypeFromAntlr = struct)
     }
 
+
     fun elementToArray(splitwords: Boolean = true): DataType {
         return if (base == BaseDataType.UWORD || base == BaseDataType.WORD || base == BaseDataType.STR) arrayFor(base, splitwords)
         else arrayFor(base, false)
     }
 
     fun elementType(): DataType =
-        if(base.isArray || base==BaseDataType.STR)
-            forDt(sub!!)
-        else
-            throw IllegalArgumentException("not an array")
+        when {
+            isPointerArray -> DataType(BaseDataType.POINTER, sub, subType)
+            base.isArray || base==BaseDataType.STR -> forDt(sub!!)
+            else -> throw IllegalArgumentException("not an array")
+        }
+
+    fun typeForAddressOf(msb: Boolean): DataType {
+        if (isUndefined)
+            return if(msb) pointer(BaseDataType.UBYTE) else UWORD
+        else {
+            if (isBasic)
+                return pointer(base)
+            if (isString)
+                return pointer(BaseDataType.UBYTE)
+            if (isPointer)
+                return UWORD
+            if (isArray) {
+                if (msb || isSplitWordArray)
+                    return pointer(BaseDataType.UBYTE)
+                val elementDt = elementType()
+                require(elementDt.isBasic)
+                return pointer(elementDt)
+            }
+            if (subType != null)
+                return pointer(this)
+            return UWORD
+        }
+    }
+
+    fun dereference(): DataType {
+        require(isPointer || isUnsignedWord)
+        return when {
+            isUnsignedWord -> forDt(BaseDataType.UBYTE)
+            sub!=null -> forDt(sub)
+            subType!=null -> DataType(BaseDataType.STRUCT_INSTANCE, null, subType)
+            subTypeFromAntlr!=null -> DataType(BaseDataType.STRUCT_INSTANCE, null, null, subTypeFromAntlr)
+            else -> throw IllegalArgumentException("cannot dereference this pointer type")
+        }
+    }
 
     override fun toString(): String = when(base) {
         BaseDataType.ARRAY -> {
@@ -148,6 +232,15 @@ class DataType private constructor(val base: BaseDataType, val sub: BaseDataType
                 else -> throw IllegalArgumentException("invalid sub type")
             }
         }
+        BaseDataType.POINTER -> {
+            if(sub!=null) "^^${sub.name.lowercase()}" else if(subType!=null) "^^${subType!!.scopedNameString}" else "^^${subTypeFromAntlr}"
+        }
+        BaseDataType.ARRAY_POINTER -> {
+            if(sub!=null) "^^${sub.name.lowercase()}[] (split)" else if (subType!=null) "^^${subType!!.scopedNameString}[] (split)" else "^^${subTypeFromAntlr}[] (split)"
+        }
+        BaseDataType.STRUCT_INSTANCE -> {
+            sub?.name?.lowercase() ?: if (subType!=null) subType!!.scopedNameString else "$subTypeFromAntlr"
+        }
         else -> base.name.lowercase()
     }
 
@@ -160,6 +253,30 @@ class DataType private constructor(val base: BaseDataType, val sub: BaseDataType
         BaseDataType.LONG -> "long"
         BaseDataType.FLOAT -> "float"
         BaseDataType.STR -> "str"
+        BaseDataType.POINTER -> {
+            when {
+                sub!=null -> "^^${sub.name.lowercase()}"
+                subType!=null -> "^^${subType!!.scopedNameString}"
+                subTypeFromAntlr!=null -> "^^${subTypeFromAntlr!!.joinToString(".")}"
+                else -> "?????"
+            }
+        }
+        BaseDataType.STRUCT_INSTANCE -> {
+            when {
+                sub!=null -> sub.name.lowercase()
+                subType!=null -> subType!!.scopedNameString
+                subTypeFromAntlr!=null -> subTypeFromAntlr!!.joinToString(".")
+                else -> "?????"
+            }
+        }
+        BaseDataType.ARRAY_POINTER -> {
+            when {
+                sub!=null -> "^^${sub.name.lowercase()}["
+                subType!=null -> "^^${subType!!.scopedNameString}["
+                subTypeFromAntlr!=null -> "^^${subTypeFromAntlr!!.joinToString(".")}["
+                else -> "????? ["
+            }
+        }
         BaseDataType.ARRAY -> {
             when(sub) {
                 BaseDataType.UBYTE -> "ubyte["
@@ -187,18 +304,37 @@ class DataType private constructor(val base: BaseDataType, val sub: BaseDataType
             BaseDataType.BOOL -> targetType.base == BaseDataType.BOOL
             BaseDataType.UBYTE -> targetType.base in arrayOf(BaseDataType.UBYTE, BaseDataType.WORD, BaseDataType.UWORD, BaseDataType.LONG, BaseDataType.FLOAT)
             BaseDataType.BYTE -> targetType.base in arrayOf(BaseDataType.BYTE, BaseDataType.WORD, BaseDataType.LONG, BaseDataType.FLOAT)
-            BaseDataType.UWORD -> targetType.base in arrayOf(BaseDataType.UWORD, BaseDataType.LONG, BaseDataType.FLOAT)
+            BaseDataType.UWORD -> targetType.base in arrayOf(BaseDataType.UWORD, BaseDataType.LONG, BaseDataType.FLOAT, BaseDataType.POINTER, BaseDataType.ARRAY_POINTER)
             BaseDataType.WORD -> targetType.base in arrayOf(BaseDataType.WORD, BaseDataType.LONG, BaseDataType.FLOAT)
             BaseDataType.LONG -> targetType.base in arrayOf(BaseDataType.LONG, BaseDataType.FLOAT)
             BaseDataType.FLOAT -> targetType.base in arrayOf(BaseDataType.FLOAT)
-            BaseDataType.STR -> targetType.base in arrayOf(BaseDataType.STR, BaseDataType.UWORD)
+            BaseDataType.STR -> targetType.base in arrayOf(BaseDataType.STR, BaseDataType.UWORD) || (targetType.isPointer && targetType.sub==BaseDataType.UBYTE)
             BaseDataType.ARRAY, BaseDataType.ARRAY_SPLITW -> targetType.base in arrayOf(BaseDataType.ARRAY, BaseDataType.ARRAY_SPLITW) && targetType.sub == sub
+            BaseDataType.POINTER -> {
+                when {
+                    targetType.base == BaseDataType.UWORD || targetType.base == BaseDataType.LONG -> true
+                    targetType.isPointer -> this.isUnsignedWord || this == targetType
+                    else -> false
+                }
+            }
+            BaseDataType.STRUCT_INSTANCE -> false        // we cannot deal with actual struct instances yet in any shape or form (only getting fields from it)
+            BaseDataType.ARRAY_POINTER -> false
             BaseDataType.UNDEFINED -> false
         }
 
     fun largerSizeThan(other: DataType): Boolean = base.largerSizeThan(other.base)
     fun equalsSize(other: DataType): Boolean = base.equalsSize(other.base)
 
+    // note: for pointer types, size() doesn't return the size of the pointer itself but the size of the thing it points to
+    fun size(memsizer: IMemSizer): Int = if(sub!=null) {
+            memsizer.memorySize(sub)
+        } else if(subType!=null) {
+            subType!!.memsize(memsizer)
+        } else {
+            memsizer.memorySize(base)
+        }
+
+    val isBasic = sub==null && subType==null && subTypeFromAntlr==null
     val isUndefined = base == BaseDataType.UNDEFINED
     val isByte = base.isByte
     val isUnsignedByte = base == BaseDataType.UBYTE
@@ -214,22 +350,27 @@ class DataType private constructor(val base: BaseDataType, val sub: BaseDataType
     val isSigned = base.isSigned
     val isUnsigned = !base.isSigned
     val isArray = base.isArray
-    val isBoolArray = base.isArray && sub == BaseDataType.BOOL
-    val isByteArray = base.isArray && (sub == BaseDataType.UBYTE || sub == BaseDataType.BYTE)
-    val isUnsignedByteArray = base.isArray && sub == BaseDataType.UBYTE
-    val isSignedByteArray = base.isArray && sub == BaseDataType.BYTE
-    val isWordArray = base.isArray && (sub == BaseDataType.UWORD || sub == BaseDataType.WORD)
-    val isUnsignedWordArray = base.isArray && sub == BaseDataType.UWORD
-    val isSignedWordArray = base.isArray && sub == BaseDataType.WORD
-    val isFloatArray = base.isArray && sub == BaseDataType.FLOAT
+    val isPointer = base.isPointer
+    val isPointerToByte = base.isPointer && sub?.isByteOrBool==true
+    val isPointerToWord = base.isPointer && sub?.isWord==true
+    val isStructInstance = base.isStructInstance
+    val isPointerArray = base.isPointerArray
+    val isBoolArray = base.isArray && !base.isPointerArray && sub == BaseDataType.BOOL
+    val isByteArray = base.isArray && !base.isPointerArray && (sub == BaseDataType.UBYTE || sub == BaseDataType.BYTE)
+    val isUnsignedByteArray = base.isArray && !base.isPointerArray && sub == BaseDataType.UBYTE
+    val isSignedByteArray = base.isArray && !base.isPointerArray && sub == BaseDataType.BYTE
+    val isWordArray = base.isArray && !base.isPointerArray && (sub == BaseDataType.UWORD || sub == BaseDataType.WORD)
+    val isUnsignedWordArray = base.isArray && !base.isPointerArray && sub == BaseDataType.UWORD
+    val isSignedWordArray = base.isArray && !base.isPointerArray && sub == BaseDataType.WORD
+    val isFloatArray = base.isArray && !base.isPointerArray && sub == BaseDataType.FLOAT
     val isString = base == BaseDataType.STR
     val isBool = base == BaseDataType.BOOL
     val isFloat = base == BaseDataType.FLOAT
     val isLong = base == BaseDataType.LONG
     val isStringly = base == BaseDataType.STR || base == BaseDataType.UWORD || (base == BaseDataType.ARRAY && (sub == BaseDataType.UBYTE || sub == BaseDataType.BYTE))
     val isSplitWordArray = base.isSplitWordArray
-    val isSplitUnsignedWordArray = base.isSplitWordArray && sub == BaseDataType.UWORD
-    val isSplitSignedWordArray = base.isSplitWordArray && sub == BaseDataType.WORD
+    val isSplitUnsignedWordArray = base.isSplitWordArray && !base.isPointerArray && sub == BaseDataType.UWORD
+    val isSplitSignedWordArray = base.isSplitWordArray && !base.isPointerArray && sub == BaseDataType.WORD
     val isIterable =  base.isIterable
     val isPassByRef = base.isPassByRef
     val isPassByValue = base.isPassByValue
@@ -280,10 +421,13 @@ enum class RegisterOrPair {
             BaseDataType.BYTE -> "sL"
             BaseDataType.WORD -> "s"
             BaseDataType.UWORD, null -> ""
-            else -> throw kotlin.IllegalArgumentException("invalid register param type")
+            else -> throw IllegalArgumentException("invalid register param type")
         }
         return listOf("cx16", name.lowercase()+suffix)
     }
+
+    fun isWord() = this==AX || this == AY || this==XY || this in Cx16VirtualRegisters
+
 }       // only used in parameter and return value specs in asm subroutines
 
 enum class Statusflag {

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

@@ -27,7 +27,7 @@ interface ICompilationTarget: IStringEncoding, IMemSizer {
     var golden: GoldenRam
     val libraryPath: Path?
     val customLauncher: List<String>
-    val additionalAssemblerOptions: String?
+    val additionalAssemblerOptions: List<String>
     val defaultOutputType: OutputType
 
     fun initializeMemoryAreas(compilerOptions: CompilationOptions)

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

@@ -14,5 +14,5 @@ interface IErrorReporter {
 
     fun noErrorForLine(position: Position): Boolean
 
-    fun print_single_error(errormessage: String)
+    fun printSingleError(errormessage: String)
 }

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

@@ -72,6 +72,7 @@ abstract class Zeropage(options: CompilationOptions): MemoryAllocator(options) {
         val size: Int =
                 when {
                     datatype.isIntegerOrBool -> options.compTarget.memorySize(datatype, null)
+                    datatype.isPointer -> options.compTarget.memorySize(datatype, null)
                     datatype.isString || datatype.isArray -> {
                         val memsize = options.compTarget.memorySize(datatype, numElements!!)
                         if(position!=null)
@@ -122,6 +123,7 @@ abstract class Zeropage(options: CompilationOptions): MemoryAllocator(options) {
                 datatype.isNumericOrBool -> VarAllocation(address, datatype, size)        // numerical variables in zeropage never have an initial value here because they are set in separate initializer assignments
                 datatype.isString -> VarAllocation(address, datatype, size)
                 datatype.isArray -> VarAllocation(address, datatype, size)
+                datatype.isPointer -> VarAllocation(address, datatype, size)
                 else -> throw AssemblyError("invalid dt")
             }
         }

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

@@ -6,12 +6,15 @@ import prog8.code.target.zp.C128Zeropage
 import java.nio.file.Path
 
 
-class C128Target: ICompilationTarget, IStringEncoding by Encoder, IMemSizer by NormalMemSizer(Mflpt5.FLOAT_MEM_SIZE) {
+class C128Target: ICompilationTarget,
+    IStringEncoding by Encoder(true),
+    IMemSizer by NormalMemSizer(Mflpt5.FLOAT_MEM_SIZE) {
+
     override val name = NAME
     override val defaultEncoding = Encoding.PETSCII
     override val libraryPath = null
-    override val customLauncher: List<String> = emptyList()
-    override val additionalAssemblerOptions = null
+    override val customLauncher = emptyList<String>()
+    override val additionalAssemblerOptions = emptyList<String>()
     override val defaultOutputType = OutputType.PRG
 
     companion object {
@@ -28,10 +31,10 @@ class C128Target: ICompilationTarget, IStringEncoding by Encoder, IMemSizer by N
     override val PROGRAM_LOAD_ADDRESS = 0x1c01u
     override val PROGRAM_MEMTOP_ADDRESS = 0xc000u
 
-    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 val BSSHIGHRAM_START = 0u    // TODO address?
+    override val BSSHIGHRAM_END = 0u      // TODO address?
+    override val BSSGOLDENRAM_START = 0u  // TODO address?
+    override val BSSGOLDENRAM_END = 0u    // TODO address?
 
     override lateinit var zeropage: Zeropage
     override lateinit var golden: GoldenRam

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

@@ -7,12 +7,15 @@ import java.io.IOException
 import java.nio.file.Path
 
 
-class C64Target: ICompilationTarget, IStringEncoding by Encoder, IMemSizer by NormalMemSizer(Mflpt5.Companion.FLOAT_MEM_SIZE) {
+class C64Target: ICompilationTarget,
+    IStringEncoding by Encoder(true),
+    IMemSizer by NormalMemSizer(Mflpt5.FLOAT_MEM_SIZE) {
+
     override val name = NAME
     override val defaultEncoding = Encoding.PETSCII
     override val libraryPath = null
-    override val customLauncher: List<String> = emptyList()
-    override val additionalAssemblerOptions = null
+    override val customLauncher = emptyList<String>()
+    override val additionalAssemblerOptions = emptyList<String>()
     override val defaultOutputType = OutputType.PRG
 
     companion object {

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

@@ -27,7 +27,7 @@ class ConfigFileTarget(
     override val defaultOutputType: OutputType,
     override val libraryPath: Path,
     override val customLauncher: List<String>,
-    override val additionalAssemblerOptions: String?,
+    override val additionalAssemblerOptions: List<String>,
     val ioAddresses: List<UIntRange>,
     val zpScratchB1: UInt,
     val zpScratchReg: UInt,
@@ -37,7 +37,7 @@ class ConfigFileTarget(
     val zpFullsafe: List<UIntRange>,
     val zpKernalsafe: List<UIntRange>,
     val zpBasicsafe: List<UIntRange>
-): ICompilationTarget, IStringEncoding by Encoder, IMemSizer by NormalMemSizer(8) {
+): ICompilationTarget, IStringEncoding by Encoder(true), IMemSizer by NormalMemSizer(8) {
 
     companion object {
 
@@ -109,8 +109,6 @@ class ConfigFileTarget(
                     (customLauncherStr+"\n").lines().map { it.trimEnd() }
                 else emptyList()
             val assemblerOptionsStr = props.getProperty("assembler_options", "").trim()
-            val assemblerOptions = assemblerOptionsStr.ifBlank { null }
-
             val outputTypeString = props.getProperty("output_type", "PRG")
             val defaultOutputType = OutputType.valueOf(outputTypeString.uppercase())
 
@@ -128,7 +126,7 @@ class ConfigFileTarget(
                 defaultOutputType,
                 libraryPath,
                 customLauncher,
-                assemblerOptions,
+                if(assemblerOptionsStr=="") emptyList() else assemblerOptionsStr.split(" "),
                 ioAddresses,
                 props.getInteger("zp_scratch_b1"),
                 props.getInteger("zp_scratch_reg"),

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

@@ -6,12 +6,15 @@ import prog8.code.target.zp.CX16Zeropage
 import java.nio.file.Path
 
 
-class Cx16Target: ICompilationTarget, IStringEncoding by Encoder, IMemSizer by NormalMemSizer(Mflpt5.Companion.FLOAT_MEM_SIZE) {
+class Cx16Target: ICompilationTarget,
+    IStringEncoding by Encoder(true),
+    IMemSizer by NormalMemSizer(Mflpt5.FLOAT_MEM_SIZE) {
+
     override val name = NAME
     override val defaultEncoding = Encoding.PETSCII
     override val libraryPath = null
-    override val customLauncher: List<String> = emptyList()
-    override val additionalAssemblerOptions = null
+    override val customLauncher = emptyList<String>()
+    override val additionalAssemblerOptions = emptyList<String>()
     override val defaultOutputType = OutputType.PRG
 
     companion object {

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

@@ -18,7 +18,7 @@ data class Mflpt5(val b0: UByte, val b1: UByte, val b2: UByte, val b3: UByte, va
             // and https://en.wikipedia.org/wiki/IEEE_754-1985
 
             val flt = num.toDouble()
-            if (flt < FLOAT_MAX_NEGATIVE || flt > FLOAT_MAX_POSITIVE)
+            if (flt !in FLOAT_MAX_NEGATIVE..FLOAT_MAX_POSITIVE)
                 throw InternalCompilerException("floating point number out of 5-byte mflpt range: $this")
             if (flt == 0.0)
                 return zero

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

@@ -7,7 +7,9 @@ import prog8.code.core.IMemSizer
 internal class NormalMemSizer(val floatsize: Int): IMemSizer {
 
     override fun memorySize(dt: DataType, numElements: Int?): Int {
-        if(dt.isArray) {
+        if(dt.isPointerArray)
+            return 2 * numElements!!        // array of pointers is just array of uwords
+        else if(dt.isArray) {
             if(numElements==null) return 2      // treat it as a pointer size
             return when(dt.sub) {
                 BaseDataType.BOOL, BaseDataType.UBYTE, BaseDataType.BYTE -> numElements
@@ -25,7 +27,9 @@ internal class NormalMemSizer(val floatsize: Int): IMemSizer {
         return when {
             dt.isByteOrBool -> 1 * (numElements ?: 1)
             dt.isFloat -> floatsize * (numElements ?: 1)
-            dt.isLong -> throw IllegalArgumentException("long can not yet be put into memory")
+            dt.isLong -> 4 * (numElements ?: 1)
+            dt.isPointer -> 2  // pointer is just a uword
+            dt.isStructInstance -> dt.subType!!.memsize(this)
             dt.isUndefined -> throw IllegalArgumentException("undefined has no memory size")
             else -> 2 * (numElements ?: 1)
         }

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

@@ -6,12 +6,15 @@ import prog8.code.target.zp.PETZeropage
 import java.nio.file.Path
 
 
-class PETTarget: ICompilationTarget, IStringEncoding by Encoder, IMemSizer by NormalMemSizer(Mflpt5.Companion.FLOAT_MEM_SIZE) {
+class PETTarget: ICompilationTarget,
+    IStringEncoding by Encoder(true),
+    IMemSizer by NormalMemSizer(Mflpt5.FLOAT_MEM_SIZE) {
+
     override val name = NAME
     override val defaultEncoding = Encoding.PETSCII
     override val libraryPath = null
-    override val customLauncher: List<String> = emptyList()
-    override val additionalAssemblerOptions = null
+    override val customLauncher = emptyList<String>()
+    override val additionalAssemblerOptions = emptyList<String>()
     override val defaultOutputType = OutputType.PRG
 
     companion object {

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

@@ -3,16 +3,20 @@ package prog8.code.target
 import prog8.code.core.*
 import prog8.code.target.encodings.Encoder
 import java.nio.file.Path
+import kotlin.io.path.extension
 import kotlin.io.path.isReadable
 import kotlin.io.path.name
 import kotlin.io.path.readText
 
-class VMTarget: ICompilationTarget, IStringEncoding by Encoder, IMemSizer by NormalMemSizer(FLOAT_MEM_SIZE) {
+class VMTarget: ICompilationTarget,
+    IStringEncoding by Encoder(false),
+    IMemSizer by NormalMemSizer(FLOAT_MEM_SIZE) {
+
     override val name = NAME
     override val defaultEncoding = Encoding.ISO
     override val libraryPath = null
-    override val customLauncher: List<String> = emptyList()
-    override val additionalAssemblerOptions = null
+    override val customLauncher = emptyList<String>()
+    override val additionalAssemblerOptions = emptyList<String>()
     override val defaultOutputType = OutputType.PRG
 
     companion object {
@@ -70,16 +74,11 @@ class VMTarget: ICompilationTarget, IStringEncoding by Encoder, IMemSizer by Nor
 
         // to not have external module dependencies in our own module, we launch the virtual machine via reflection
         val vm = Class.forName("prog8.vm.VmRunner").getDeclaredConstructor().newInstance() as IVirtualMachineRunner
-        val filename = programNameWithPath.name
-        if(programNameWithPath.isReadable()) {
-            vm.runProgram(programNameWithPath.readText(), quiet)
-        } else {
-            val withExt = programNameWithPath.resolveSibling("$filename.p8ir")
-            if(withExt.isReadable())
-                vm.runProgram(withExt.readText(), quiet)
-            else
-                throw java.nio.file.NoSuchFileException(withExt.name, null, "not a .p8ir file")
-        }
+        val withExt = if(programNameWithPath.extension=="p8ir") programNameWithPath else programNameWithPath.resolveSibling("${programNameWithPath.name}.p8ir")
+        if(withExt.isReadable())
+            vm.runProgram(withExt.readText(), quiet)
+        else
+            throw java.nio.file.NoSuchFileException(withExt.name, null, "not a .p8ir file")
     }
 
     override fun isIOAddress(address: UInt): Boolean = false
@@ -88,31 +87,6 @@ class VMTarget: ICompilationTarget, IStringEncoding by Encoder, IMemSizer by Nor
         zeropage = VirtualZeropage(compilerOptions)
         golden = GoldenRam(compilerOptions, UIntRange.EMPTY)
     }
-
-    override fun memorySize(dt: DataType, numElements: Int?): Int {
-        if(dt.isArray) {
-            if(numElements==null) return 2      // treat it as a pointer size
-            return when(dt.sub) {
-                BaseDataType.BOOL, BaseDataType.UBYTE, BaseDataType.BYTE -> numElements
-                BaseDataType.UWORD, BaseDataType.WORD, BaseDataType.STR -> numElements * 2
-                BaseDataType.FLOAT-> numElements * FLOAT_MEM_SIZE
-                BaseDataType.UNDEFINED -> throw IllegalArgumentException("undefined has no memory size")
-                else -> throw IllegalArgumentException("invalid sub type")
-            }
-        }
-        else if (dt.isString) {
-            return numElements        // treat it as the size of the given string with the length
-                ?: 2    // treat it as the size to store a string pointer
-        }
-
-        return when {
-            dt.isByteOrBool -> 1 * (numElements ?: 1)
-            dt.isFloat -> FLOAT_MEM_SIZE * (numElements ?: 1)
-            dt.isLong -> throw IllegalArgumentException("long can not yet be put into memory")
-            dt.isUndefined -> throw IllegalArgumentException("undefined has no memory size")
-            else -> 2 * (numElements ?: 1)
-        }
-    }
 }
 
 

codeCore/src/prog8/code/target/encodings/AtasciiEncoding.kt

@@ -197,6 +197,7 @@ object AtasciiEncoding {
     fun encode(str: String): Result<List<UByte>, CharConversionException> {
         val mapped = str.map { chr ->
             when (chr) {
+                '\r' -> 0x9bu
                 '\u0000' -> 0u
                 in '\u8000'..'\u80ff' -> {
                     // special case: take the lower 8 bit hex value directly

codeCore/src/prog8/code/target/encodings/C64osEncoding.kt

@@ -285,6 +285,7 @@ object C64osEncoding {
             val screencode = encodingC64os[chr]
             return screencode?.toUByte() ?: when (chr) {
                 '\u0000' -> 0u
+                '\n' -> 13u
                 in '\u8000'..'\u80ff' -> {
                     // special case: take the lower 8 bit hex value directly
                     (chr.code - 0x8000).toUByte()

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

@@ -5,19 +5,19 @@ import prog8.code.core.Encoding
 import prog8.code.core.IStringEncoding
 import prog8.code.core.InternalCompilerException
 
-object Encoder: IStringEncoding {
+class Encoder(val newlineToCarriageReturn: Boolean): 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)
             Encoding.SCREENCODES -> PetsciiEncoding.encodeScreencode(str, true)
-            Encoding.ISO -> IsoEncoding.encode(str)
-            Encoding.ATASCII -> AtasciiEncoding.encode(str)
-            Encoding.ISO5 -> IsoCyrillicEncoding.encode(str)
-            Encoding.ISO16 -> IsoEasternEncoding.encode(str)
+            Encoding.ISO -> IsoEncoding.encode(str, newlineToCarriageReturn)
+            Encoding.ISO5 -> IsoCyrillicEncoding.encode(str, newlineToCarriageReturn)
+            Encoding.ISO16 -> IsoEasternEncoding.encode(str, newlineToCarriageReturn)
             Encoding.CP437 -> Cp437Encoding.encode(str)
-            Encoding.KATAKANA -> KatakanaEncoding.encode(str)
+            Encoding.KATAKANA -> KatakanaEncoding.encode(str, newlineToCarriageReturn)
+            Encoding.ATASCII -> AtasciiEncoding.encode(str)
             Encoding.C64OS -> C64osEncoding.encode(str)
             else -> throw InternalCompilerException("unsupported encoding $encoding")
         }
@@ -30,12 +30,12 @@ object Encoder: IStringEncoding {
         val decoded = when(encoding) {
             Encoding.PETSCII -> PetsciiEncoding.decodePetscii(bytes, true)
             Encoding.SCREENCODES -> PetsciiEncoding.decodeScreencode(bytes, true)
-            Encoding.ISO -> IsoEncoding.decode(bytes)
-            Encoding.ATASCII -> AtasciiEncoding.decode(bytes)
-            Encoding.ISO5 -> IsoCyrillicEncoding.decode(bytes)
-            Encoding.ISO16 -> IsoEasternEncoding.decode(bytes)
+            Encoding.ISO -> IsoEncoding.decode(bytes, newlineToCarriageReturn)
+            Encoding.ISO5 -> IsoCyrillicEncoding.decode(bytes, newlineToCarriageReturn)
+            Encoding.ISO16 -> IsoEasternEncoding.decode(bytes, newlineToCarriageReturn)
             Encoding.CP437 -> Cp437Encoding.decode(bytes)
-            Encoding.KATAKANA -> KatakanaEncoding.decode(bytes)
+            Encoding.KATAKANA -> KatakanaEncoding.decode(bytes, newlineToCarriageReturn)
+            Encoding.ATASCII -> AtasciiEncoding.decode(bytes)
             Encoding.C64OS -> C64osEncoding.decode(bytes)
             else -> throw InternalCompilerException("unsupported encoding $encoding")
         }

codeCore/src/prog8/code/target/encodings/IsoEncoding.kt

@@ -6,14 +6,16 @@ import com.github.michaelbull.result.Result
 import java.io.CharConversionException
 import java.nio.charset.Charset
 
+
 open class IsoEncodingBase(charsetName: String) {
     val charset: Charset = Charset.forName(charsetName)
 
-    fun encode(str: String): Result<List<UByte>, CharConversionException> {
+    fun encode(str: String, newlineToCarriageReturn: Boolean): Result<List<UByte>, CharConversionException> {
         return try {
             val mapped = str.map { chr ->
                 when (chr) {
                     '\u0000' -> 0u
+                    '\n' -> if(newlineToCarriageReturn) 13u else 10u
                     in '\u8000'..'\u80ff' -> {
                         // special case: take the lower 8 bit hex value directly
                         (chr.code - 0x8000).toUByte()
@@ -27,9 +29,14 @@ open class IsoEncodingBase(charsetName: String) {
         }
     }
 
-    fun decode(bytes: Iterable<UByte>): Result<String, CharConversionException> {
+    fun decode(bytes: Iterable<UByte>, newlineToCarriageReturn: Boolean): Result<String, CharConversionException> {
         return try {
-            Ok(String(bytes.map { it.toByte() }.toByteArray(), charset))
+            Ok(String(bytes.map {
+                when(it) {
+                    13u.toUByte() -> if(newlineToCarriageReturn) 10 else 13
+                    else -> it.toByte()
+                }
+            }.toByteArray(), charset))
         } catch (ce: CharConversionException) {
             Err(ce)
         }

codeCore/src/prog8/code/target/encodings/KatakanaEncoding.kt

@@ -64,10 +64,11 @@ object JapaneseCharacterConverter {
 object KatakanaEncoding {
     val charset: Charset = Charset.forName("JIS_X0201")
 
-    fun encode(str: String): Result<List<UByte>, CharConversionException> {
+    fun encode(str: String, newlineToCarriageReturn: Boolean): Result<List<UByte>, CharConversionException> {
         return try {
             val mapped = str.map { chr ->
                 when (chr) {
+                    '\n' -> if(newlineToCarriageReturn) 13u else 10u
 
                     '\u0000' -> 0u
                     '\u00a0' -> 0xa0u // $a0 isn't technically a part of JIS X 0201 spec, and so we need to handle this ourselves
@@ -112,9 +113,14 @@ object KatakanaEncoding {
         }
     }
 
-    fun decode(bytes: Iterable<UByte>): Result<String, CharConversionException> {
+    fun decode(bytes: Iterable<UByte>, newlineToCarriageReturn: Boolean): Result<String, CharConversionException> {
         return try {
-            Ok(String(bytes.map { it.toByte() }.toByteArray(), charset))
+            Ok(String(bytes.map {
+                when(it) {
+                    13u.toUByte() -> if(newlineToCarriageReturn) 10 else 13
+                    else -> it.toByte()
+                }
+            }.toByteArray(), charset))
         } catch (ce: CharConversionException) {
             Err(ce)
         }

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

@@ -21,7 +21,7 @@ object PetsciiEncoding {
         '\ufffe',    //       0x07 -> UNDEFINED
         '\uf118',    //       0x08 -> DISABLE CHARACTER SET SWITCHING (CUS)
         '\uf119',    //       0x09 -> ENABLE CHARACTER SET SWITCHING (CUS)
-        '\ufffe',    //       0x0A -> UNDEFINED
+        '\n',        //       0x0A -> LINE FEED (RETURN)
         '\ufffe',    //       0x0B -> UNDEFINED
         '\ufffe',    //       0x0C -> UNDEFINED
         '\n'    ,    //       0x0D -> LINE FEED (RETURN)
@@ -1117,6 +1117,8 @@ object PetsciiEncoding {
             val screencode = if(lowercase) encodingScreencodeLowercase[chr] else encodingScreencodeUppercase[chr]
             return screencode?.toUByte() ?: when (chr) {
                 '\u0000' -> 0u
+                '\n' -> 141u
+                '\r' -> 141u
                 in '\u8000'..'\u80ff' -> {
                     // special case: take the lower 8 bit hex value directly
                     (chr.code - 0x8000).toUByte()

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

@@ -16,12 +16,6 @@ class C128Zeropage(options: CompilationOptions) : Zeropage(options) {
     override val SCRATCH_W2 = 0xfdu      // temp storage 2 for a word  $fd+$fe
 
     init {
-        if (options.floats) {
-            throw InternalCompilerException("C128 target doesn't yet support floating point routines")
-            // note: in git commit labeled 'c128: remove floats module' the floats.p8 and floats.asm files are removed,
-            //       they could be retrieved again at a later time if the compiler somehow *does* store the fp variables in bank1.
-        }
-
         if (options.floats && options.zeropage !in arrayOf(
                 ZeropageType.FLOATSAFE,
                 ZeropageType.BASICSAFE,

codeCore/src/prog8/code/target/zp/ConfigurableZeropage.kt

@@ -19,7 +19,7 @@ class ConfigurableZeropage(
 
     init {
         if (options.floats) {
-            TODO("floats")
+            TODO("floats in configurable target zp")
         }
 
         if(SCRATCH_REG!=SCRATCH_B1+1u)
@@ -30,7 +30,7 @@ class ConfigurableZeropage(
             ZeropageType.FULL -> fullsafe.forEach { free.addAll(it) }
             ZeropageType.BASICSAFE -> basicsafe.forEach { free.addAll(it) }
             ZeropageType.KERNALSAFE -> kernalsafe.forEach { free.addAll(it) }
-            ZeropageType.FLOATSAFE -> TODO("floatsafe")
+            ZeropageType.FLOATSAFE -> TODO("floatsafe in configurable target zp")
         }
 
         val distinctFree = free.distinct()

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

@@ -16,10 +16,6 @@ class PETZeropage(options: CompilationOptions) : Zeropage(options) {
     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,

codeGenCpu6502/build.gradle.kts

@@ -1,5 +1,3 @@
-import org.jetbrains.kotlin.gradle.dsl.JvmTarget
-
 plugins {
     kotlin("jvm")
 }
@@ -9,12 +7,10 @@ dependencies {
     implementation(project(":simpleAst"))
     // implementation("org.jetbrains.kotlin:kotlin-stdlib-jdk8")
     // implementation "org.jetbrains.kotlin:kotlin-reflect"
-    implementation("com.michael-bull.kotlin-result:kotlin-result-jvm:2.0.1")
+    implementation("com.michael-bull.kotlin-result:kotlin-result-jvm:2.1.0")
 
     testImplementation("io.kotest:kotest-runner-junit5-jvm:5.9.1")
     testImplementation("io.kotest:kotest-framework-datatest:5.9.1")
-    testImplementation("org.junit.jupiter:junit-jupiter:5.9.1")
-    testRuntimeOnly("org.junit.platform:junit-platform-launcher")
 }
 
 sourceSets {

codeGenCpu6502/codeGenCpu6502.iml

@@ -13,7 +13,6 @@
     <orderEntry type="module" module-name="codeCore" />
     <orderEntry type="module" module-name="simpleAst" />
     <orderEntry type="library" name="michael.bull.kotlin.result.jvm" level="project" />
-    <orderEntry type="library" name="io.kotest.assertions.core.jvm" level="project" />
     <orderEntry type="library" name="io.kotest.runner.junit5.jvm" level="project" />
     <orderEntry type="library" name="io.kotest.framework.datatest" level="project" />
   </component>

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

@@ -30,14 +30,17 @@ class AsmGen6502(val prefixSymbols: Boolean, private val lastGeneratedLabelSeque
     private fun prefixSymbols(program: PtProgram, options: CompilationOptions, st: SymbolTable): SymbolTable {
         val nodesToPrefix = mutableListOf<Pair<PtNode, Int>>()              // parent + index
         val functionCallsToPrefix = mutableListOf<Pair<PtNode, Int>>()      // parent + index
+        val expressionsToFixSubtype = mutableListOf<PtExpression>()
+        val variablesToFixSubtype = mutableListOf<IPtVariable>()
 
         fun prefixNamedNode(node: PtNamedNode) {
             when(node) {
                 is PtAsmSub, is PtSub -> node.name = "p8s_${node.name}"
                 is PtBlock -> node.name = "p8b_${node.name}"
-                is PtLabel -> if(!node.name.startsWith(GENERATED_LABEL_PREFIX)) node.name = "p8l_${node.name}"   // don't prefix autogenerated labels
+                is PtLabel -> if(!node.name.startsWith(GENERATED_LABEL_PREFIX)) node.name = "p8l_${node.name}"   // only prefix user defined labels
                 is PtConstant -> node.name = "p8c_${node.name}"
                 is PtVariable, is PtMemMapped, is PtSubroutineParameter -> node.name = "p8v_${node.name}"
+                is PtStructDecl -> node.name = "p8t_${node.name}"
             }
         }
 
@@ -50,10 +53,7 @@ class AsmGen6502(val prefixSymbols: Boolean, private val lastGeneratedLabelSeque
                         node.address!!.varbank = node.address!!.varbank!!.prefix(node, st)
                     }
                 }
-                is PtSub -> {
-                    prefixNamedNode(node)
-                    node.parameters.forEach { prefixNamedNode(it) }
-                }
+                is PtSub -> prefixNamedNode(node)
                 is PtFunctionCall -> {
                     val stNode = st.lookup(node.name)!!
                     if(stNode.astNode!!.definingBlock()?.options?.noSymbolPrefixing!=true) {
@@ -62,11 +62,28 @@ class AsmGen6502(val prefixSymbols: Boolean, private val lastGeneratedLabelSeque
                     }
                 }
                 is PtIdentifier -> {
+                    // check if the identifier is part of a pointer dereference (which means you cannot look it up in the symboltable because it's a struct field)
+                    val pexpr = node.parent as? PtBinaryExpression
+                    if(pexpr?.operator==".") {
+                        if(pexpr.left is PtArrayIndexer) {
+                            val arrayvar = (pexpr.left as PtArrayIndexer).variable!!
+                            if(arrayvar.type.subType!=null) {
+                                // don't prefix a struct field name here, we take care of that at asm generation time, which was a lot easier
+                                //nodesToPrefix += node.parent to node.parent.children.indexOf(node)
+                                return
+                            } else
+                                throw AssemblyError("can only use deref expression on struct type")
+                        } else {
+                            TODO("handle other left operand ${pexpr.left }in dereferencing of struct fields ${node.position}")
+                        }
+                    }
+                    // normal (non pointer deref) expression
                     var lookupName = node.name
                     if(node.type.isSplitWordArray && (lookupName.endsWith("_lsb") || lookupName.endsWith("_msb"))) {
                         lookupName = lookupName.dropLast(4)
                     }
-                    val stNode = st.lookup(lookupName) ?: throw AssemblyError("unknown identifier $node")
+                    val stNode = st.lookup(lookupName) ?:
+                        throw AssemblyError("unknown identifier $node")
                     if(stNode.astNode!!.definingBlock()?.options?.noSymbolPrefixing!=true) {
                         val index = node.parent.children.indexOf(node)
                         nodesToPrefix += node.parent to index
@@ -81,8 +98,28 @@ class AsmGen6502(val prefixSymbols: Boolean, private val lastGeneratedLabelSeque
                     val index = node.parent.children.indexOf(node)
                     nodesToPrefix += node.parent to index
                 }
+                is PtStructDecl -> prefixNamedNode(node)        // note: field names are not prefixed here, we take care of that at asm generation time, which was a lot easier
+                is PtBuiltinFunctionCall -> {
+                    // could be a struct instance creation
+                    if(node.name=="prog8_lib_structalloc") {
+                        val struct = node.type.subType!!
+                        if(struct is StStruct) {
+                            // update link to active symboltable node
+                            node.type.subType = st.lookup(struct.scopedNameString) as StStruct
+                        }
+                    }
+                }
                 else -> { }
             }
+
+            if(node is IPtVariable) {
+                if(node.type.subType!=null)
+                    variablesToFixSubtype.add(node)
+            } else if(node is PtExpression) {
+                if(node.type.subType!=null)
+                    expressionsToFixSubtype.add(node)
+            }
+
             node.children.forEach { prefixSymbols(it) }
         }
 
@@ -139,8 +176,40 @@ class AsmGen6502(val prefixSymbols: Boolean, private val lastGeneratedLabelSeque
             }
         }
 
-        return SymbolTableMaker(program, options).make()
+
+        val updatedSt = SymbolTableMaker(program, options).make()
+
+        fun findSubtypeReplacement(sub: ISubType): StStruct? {
+            if(updatedSt.lookup(sub.scopedNameString)!=null)
+                return null
+            val old = st.lookup(sub.scopedNameString)
+            if(old==null)
+                throw AssemblyError("old subtype not found: ${sub.scopedNameString}")
+
+            val prefixed = ArrayDeque<String>()
+            var node: StNode = old
+            while(node.type!= StNodeType.GLOBAL) {
+                val typeChar = typePrefixChar(node.type)
+                prefixed.addFirst("p8${typeChar}_${node.name}")
+                node=node.parent
+            }
+            return updatedSt.lookup(prefixed.joinToString(".")) as StStruct
+        }
+
+        expressionsToFixSubtype.forEach { node ->
+            findSubtypeReplacement(node.type.subType!!)?.let {
+                node.type.subType = it
+            }
+        }
+        variablesToFixSubtype.forEach { node ->
+            findSubtypeReplacement(node.type.subType!!)?.let {
+                node.type.subType = it
+            }
+        }
+
+        return updatedSt
     }
+
 }
 
 private fun prefixScopedName(name: String, type: Char): String {
@@ -175,10 +244,10 @@ private fun PtVariable.prefix(parent: PtNode, st: SymbolTable): PtVariable {
                     if(elt.definingBlock()?.options?.noSymbolPrefixing==true)
                         newValue.add(elt)
                     else {
-                        val newAddr = PtAddressOf(elt.position)
-                        newAddr.children.add(elt.identifier.prefix(newAddr, st))
-                        if(elt.arrayIndexExpr!=null)
-                            newAddr.children.add(elt.arrayIndexExpr!!)
+                        val newAddr = PtAddressOf(elt.type, false, elt.position)
+                        newAddr.add(elt.identifier!!.prefix(newAddr, st))
+                        if (elt.arrayIndexExpr != null)
+                            newAddr.add(elt.arrayIndexExpr!!)
                         newAddr.parent = arrayValue
                         newValue.add(newAddr)
                     }
@@ -186,7 +255,7 @@ private fun PtVariable.prefix(parent: PtNode, st: SymbolTable): PtVariable {
                 else -> throw AssemblyError("weird array value element $elt")
             }
         }
-        val result = PtVariable(name, type, zeropage, align, newValue, arraySize, position)
+        val result = PtVariable(name, type, zeropage, align, dirty, newValue, arraySize, position)
         result.parent = parent
         result
     }
@@ -207,19 +276,34 @@ private fun PtFunctionCall.withNewName(name: String): PtFunctionCall {
 }
 
 private fun PtIdentifier.prefix(parent: PtNode, st: SymbolTable): PtIdentifier {
-    var target = st.lookup(name)
+    val targetNt: StNodeType
+    val target = st.lookup(name)
     if(target?.astNode?.definingBlock()?.options?.noSymbolPrefixing==true)
         return this
 
     if(target==null) {
         if(name.endsWith("_lsb") || name.endsWith("_msb")) {
-            target = st.lookup(name.dropLast(4))
-            if(target?.astNode?.definingBlock()?.options?.noSymbolPrefixing==true)
+            val target2 = st.lookup(name.dropLast(4))
+            if(target2?.astNode?.definingBlock()?.options?.noSymbolPrefixing==true)
                 return this
+            targetNt = target2!!.type
+        } else {
+            // if no target found, assume that the identifier is a struct field
+            targetNt = StNodeType.STATICVAR
         }
+    } else {
+        targetNt = target.type
     }
 
-    val prefixType = when(target!!.type) {
+    val prefixType = typePrefixChar(targetNt)
+    val newName = prefixScopedName(name, prefixType)
+    val node = PtIdentifier(newName, type, position)
+    node.parent = parent
+    return node
+}
+
+private fun typePrefixChar(targetNt: StNodeType): Char {
+    return when(targetNt) {
         StNodeType.BLOCK -> 'b'
         StNodeType.SUBROUTINE, StNodeType.EXTSUB -> 's'
         StNodeType.LABEL -> 'l'
@@ -227,12 +311,10 @@ private fun PtIdentifier.prefix(parent: PtNode, st: SymbolTable): PtIdentifier {
         StNodeType.CONSTANT -> 'c'
         StNodeType.BUILTINFUNC -> 's'
         StNodeType.MEMORYSLAB -> 'v'
+        StNodeType.STRUCT -> 't'
+        StNodeType.STRUCTINSTANCE -> 'i'
         else -> '?'
     }
-    val newName = prefixScopedName(name, prefixType)
-    val node = PtIdentifier(newName, type, position)
-    node.parent = parent
-    return node
 }
 
 
@@ -255,10 +337,17 @@ class AsmGen6502Internal (
     private val functioncallAsmGen = FunctionCallAsmGen(program, this)
     private val programGen = ProgramAndVarsGen(program, options, errors, symbolTable, functioncallAsmGen, this, allocator, zeropage)
     private val anyExprGen = AnyExprAsmGen(this)
-    private val assignmentAsmGen = AssignmentAsmGen(program, this, anyExprGen, allocator)
+    private val pointerGen = PointerAssignmentsGen(this, allocator)
+    private val assignmentAsmGen = AssignmentAsmGen(program, this, pointerGen, anyExprGen, allocator)
     private val builtinFunctionsAsmGen = BuiltinFunctionsAsmGen(program, this, assignmentAsmGen)
-    private val ifElseAsmgen = IfElseAsmGen(program, symbolTable, this, assignmentAsmGen, errors)
+    private val ifElseAsmgen = IfElseAsmGen(program, symbolTable, this, pointerGen, assignmentAsmGen, errors)
     private val ifExpressionAsmgen = IfExpressionAsmGen(this, assignmentAsmGen, errors)
+    private val augmentableAsmGen = AugmentableAssignmentAsmGen(program, assignmentAsmGen, this, pointerGen, allocator)
+
+    init {
+        assignmentAsmGen.augmentableAsmGen = augmentableAsmGen
+        pointerGen.augmentableAsmGen = augmentableAsmGen
+    }
 
     fun compileToAssembly(): IAssemblyProgram? {
 
@@ -316,9 +405,9 @@ class AsmGen6502Internal (
         if(symbolTable.allVariables.isNotEmpty()) {
             println("Static variables (not in ZeroPage):")
             symbolTable.allVariables
-                .filterNot { allocator.isZpVar(it.scopedName) }
-                .sortedBy { it.scopedName }.forEach {
-                    println("  ${it.dt}\t${it.scopedName}\t")
+                .filterNot { allocator.isZpVar(it.scopedNameString) }
+                .sortedBy { it.scopedNameString }.forEach {
+                    println("  ${it.dt}\t${it.scopedNameString}\t")
                 }
         }
         if(allocator.globalFloatConsts.isNotEmpty()) {
@@ -330,9 +419,9 @@ class AsmGen6502Internal (
         if(symbolTable.allMemMappedVariables.isNotEmpty()) {
             println("Memory mapped:")
             symbolTable.allMemMappedVariables
-                .sortedWith( compareBy( {it.address}, {it.scopedName} ))
+                .sortedWith( compareBy( {it.address}, {it.scopedNameString} ))
                 .forEach { mvar ->
-                    println("  $${mvar.address.toString(16).padStart(4, '0')}\t${mvar.dt}\t${mvar.scopedName}")
+                    println("  $${mvar.address.toString(16).padStart(4, '0')}\t${mvar.dt}\t${mvar.scopedNameString}")
                 }
         }
         if(symbolTable.allMemorySlabs.isNotEmpty()) {
@@ -420,7 +509,7 @@ class AsmGen6502Internal (
     }
 
     fun asmVariableName(st: StNode, scope: IPtSubroutine?): String {
-        val name = asmVariableName(st.scopedName)
+        val name = asmVariableName(st.scopedNameString)
         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)
@@ -432,23 +521,6 @@ class AsmGen6502Internal (
     }
 
 
-    internal val tempVarsCounters = mutableMapOf(
-        BaseDataType.BOOL to 0,
-        BaseDataType.BYTE to 0,
-        BaseDataType.UBYTE to 0,
-        BaseDataType.WORD to 0,
-        BaseDataType.UWORD to 0,
-        BaseDataType.LONG to 0,
-        BaseDataType.FLOAT to 0
-    )
-
-    internal fun buildTempVarName(dt: BaseDataType, counter: Int): String = "prog8_tmpvar_${dt.toString().lowercase()}_$counter"
-
-    internal fun getTempVarName(dt: BaseDataType): String {
-        tempVarsCounters[dt] = tempVarsCounters.getValue(dt)+1
-        return buildTempVarName(dt, tempVarsCounters.getValue(dt))
-    }
-
     internal fun loadByteFromPointerIntoA(pointervar: PtIdentifier): String {
         // returns the source name of the zero page pointervar if it's already in the ZP,
         // otherwise returns "P8ZP_SCRATCH_W1" which is the intermediary
@@ -638,7 +710,7 @@ class AsmGen6502Internal (
             is PtDefer -> throw AssemblyError("defer should have been transformed")
             is PtNodeGroup -> stmt.children.forEach { translate(it) }
             is PtJmpTable -> translate(stmt)
-            is PtNop -> {}
+            is PtNop, is PtStructDecl, is PtSubSignature -> {}
             else -> throw AssemblyError("missing asm translation for $stmt")
         }
     }
@@ -647,6 +719,8 @@ class AsmGen6502Internal (
         val reg = register.toString().lowercase()
         val indexnum = expr.index.asConstInteger()
         if (indexnum != null) {
+            if(indexnum > 255)
+                throw AssemblyError("array index $indexnum is larger than a byte ${expr.position}")
             val indexValue = if(expr.splitWords)
                 indexnum
             else
@@ -655,17 +729,20 @@ class AsmGen6502Internal (
             return
         }
 
+        if(!expr.index.type.isByte)
+            throw AssemblyError("array index $indexnum is larger than a byte ${expr.position}")
+
         if(expr.splitWords) {
-            assignExpressionToRegister(expr.index, RegisterOrPair.fromCpuRegister(register), false)
+            assignExpressionToRegister(expr.index, RegisterOrPair.fromCpuRegister(register))
             return
         }
 
         when  {
             expr.type.isByteOrBool -> {
-                assignExpressionToRegister(expr.index, RegisterOrPair.fromCpuRegister(register), false)
+                assignExpressionToRegister(expr.index, RegisterOrPair.fromCpuRegister(register))
             }
             expr.type.isWord -> {
-                assignExpressionToRegister(expr.index, RegisterOrPair.A, false)
+                assignExpressionToRegister(expr.index, RegisterOrPair.A)
                 out("  asl  a")
                 when (register) {
                     CpuRegister.A -> {}
@@ -674,8 +751,9 @@ class AsmGen6502Internal (
                 }
             }
             expr.type.isFloat -> {
-                require(options.compTarget.FLOAT_MEM_SIZE == 5) {"invalid float size ${expr.position}"}
-                assignExpressionToRegister(expr.index, RegisterOrPair.A, false)
+                if(options.compTarget.FLOAT_MEM_SIZE != 5)
+                    TODO("support float size other than 5 ${expr.position}")
+                assignExpressionToRegister(expr.index, RegisterOrPair.A)
                 out("""
                     sta  P8ZP_SCRATCH_REG
                     asl  a
@@ -733,15 +811,15 @@ class AsmGen6502Internal (
                     when(target.kind) {
                         TargetStorageKind.VARIABLE -> {
                             if (isTargetCpu(CpuType.CPU6502))
-                                out("lda  #0 |  sta  ${target.asmVarname}")
+                                out("  lda  #0 |  sta  ${target.asmVarname}")
                             else
-                                out("stz  ${target.asmVarname}")
+                                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()}")
+                                    out("  lda  #0 |  sta  ${address.toHex()}")
                                 else
                                     out("  stz  ${address.toHex()}")
                                 return
@@ -750,7 +828,7 @@ class AsmGen6502Internal (
                         TargetStorageKind.REGISTER -> {
                             val zero = PtNumber(BaseDataType.UBYTE, 0.0, value.position)
                             zero.parent = value
-                            assignExpressionToRegister(zero, target.register!!, false)
+                            assignExpressionToRegister(zero, target.register!!)
                             return
                         }
                         else -> { }
@@ -760,6 +838,7 @@ class AsmGen6502Internal (
                 assignExpressionToRegister(value, RegisterOrPair.A)
                 assignmentAsmGen.assignRegisterByte(target, CpuRegister.A, target.datatype.isSigned, false)
             }
+            target.datatype.isPointer -> TODO("assign expression to pointer ${target.position}")
             target.datatype.isWord || target.datatype.isPassByRef -> {
                 assignExpressionToRegister(value, RegisterOrPair.AY)
                 translateNormalAssignment(
@@ -812,7 +891,7 @@ class AsmGen6502Internal (
                 when {
                     iterations == 0 -> {}
                     iterations == 1 -> translate(stmt.statements)
-                    iterations<0 || iterations>65536 -> throw AssemblyError("invalid number of iterations")
+                    iterations !in 0..65536 -> throw AssemblyError("invalid number of iterations")
                     iterations <= 256 -> repeatByteCount(iterations, stmt)
                     else -> repeatWordCount(iterations, stmt)
                 }
@@ -854,7 +933,7 @@ class AsmGen6502Internal (
     private fun repeatWordCount(iterations: Int, stmt: PtRepeatLoop) {
         require(iterations in 257..65536) { "invalid repeat count ${stmt.position}" }
         val repeatLabel = makeLabel("repeat")
-        val counterVar = createRepeatCounterVar(BaseDataType.UWORD, isTargetCpu(CpuType.CPU65C02), stmt)
+        val counterVar = createTempVarReused(BaseDataType.UWORD, true, stmt)
         val loopcount = if(iterations==65536) 0 else if(iterations and 0x00ff == 0) iterations else iterations + 0x0100   // so that the loop can simply use a double-dec
         out("""
             ldy  #>$loopcount
@@ -874,7 +953,7 @@ $repeatLabel""")
         // note: A/Y must have been loaded with the number of iterations!
         // the iny + double dec is microoptimization of the 16 bit loop
         val repeatLabel = makeLabel("repeat")
-        val counterVar = createRepeatCounterVar(BaseDataType.UWORD, false, stmt)
+        val counterVar = createTempVarReused(BaseDataType.UWORD, true, stmt)
         out("""
             cmp  #0
             beq  +
@@ -897,13 +976,13 @@ $repeatLabel""")
         require(count in 2..256) { "invalid repeat count ${stmt.position}" }
         val repeatLabel = makeLabel("repeat")
         if(isTargetCpu(CpuType.CPU65C02)) {
-            val counterVar = createRepeatCounterVar(BaseDataType.UBYTE, true, stmt)
+            val counterVar = createTempVarReused(BaseDataType.UBYTE, true, stmt)
             out("  lda  #${count and 255} |  sta  $counterVar")
             out(repeatLabel)
             translate(stmt.statements)
             out("  dec  $counterVar |  bne  $repeatLabel")
         } else {
-            val counterVar = createRepeatCounterVar(BaseDataType.UBYTE, false, stmt)
+            val counterVar = createTempVarReused(BaseDataType.UBYTE, false, stmt)
             out("  lda  #${count and 255} |  sta  $counterVar")
             out(repeatLabel)
             translate(stmt.statements)
@@ -915,13 +994,13 @@ $repeatLabel""")
         val repeatLabel = makeLabel("repeat")
         out("  cpy  #0")
         if(isTargetCpu(CpuType.CPU65C02)) {
-            val counterVar = createRepeatCounterVar(BaseDataType.UBYTE, true, stmt)
+            val counterVar = createTempVarReused(BaseDataType.UBYTE, true, stmt)
             out("  beq  $endLabel |  sty  $counterVar")
             out(repeatLabel)
             translate(stmt.statements)
             out("  dec  $counterVar |  bne  $repeatLabel")
         } else {
-            val counterVar = createRepeatCounterVar(BaseDataType.UBYTE, false, stmt)
+            val counterVar = createTempVarReused(BaseDataType.UBYTE, false, stmt)
             out("  beq  $endLabel |  sty  $counterVar")
             out(repeatLabel)
             translate(stmt.statements)
@@ -930,43 +1009,9 @@ $repeatLabel""")
         out(endLabel)
     }
 
-    private fun createRepeatCounterVar(dt: BaseDataType, preferZeropage: Boolean, stmt: PtRepeatLoop): String {
-        val scope = stmt.definingISub()!!
-        val asmInfo = subroutineExtra(scope)
-        var parent = stmt.parent
-        while(parent !is PtProgram) {
-            if(parent is PtRepeatLoop)
-                break
-            parent = parent.parent
-        }
-        val isNested = parent is PtRepeatLoop
-
-        if(!isNested) {
-            // we can re-use a counter var from the subroutine if it already has one for that datatype
-            val existingVar = asmInfo.extraVars.firstOrNull { it.first==dt && it.second.endsWith("counter") }
-            if(existingVar!=null) {
-                if(!preferZeropage || existingVar.third!=null)
-                    return existingVar.second
-            }
-        }
-
-        val counterVar = makeLabel("counter")
-        when(dt) {
-            BaseDataType.UBYTE, BaseDataType.UWORD -> {
-                val result = zeropage.allocate(counterVar, DataType.forDt(dt), null, stmt.position, errors)
-                result.fold(
-                    success = { (address, _, _) -> asmInfo.extraVars.add(Triple(dt, counterVar, address)) },
-                    failure = { asmInfo.extraVars.add(Triple(dt, counterVar, null)) }  // allocate normally
-                )
-                return counterVar
-            }
-            else -> throw AssemblyError("invalidt dt")
-        }
-    }
-
     private fun translate(stmt: PtWhen) {
         val endLabel = makeLabel("when_end")
-        val choiceBlocks = mutableListOf<Pair<String, PtNodeGroup>>()
+        val choiceBlocks = mutableListOf<Pair<String, PtWhenChoice>>()
         val conditionDt = stmt.value.type
         if(conditionDt.isByte)
             assignExpressionToRegister(stmt.value, RegisterOrPair.A)
@@ -977,13 +1022,20 @@ $repeatLabel""")
             val choice = choiceNode as PtWhenChoice
             var choiceLabel = makeLabel("choice")
             if(choice.isElse) {
+                require(choice.parent.children.last() === choice)
                 translate(choice.statements)
+                // is always the last node so can fall through
             } else {
                 if(choice.statements.children.isEmpty()) {
                     // no statements for this choice value, jump to the end immediately
                     choiceLabel = endLabel
                 } else {
-                    choiceBlocks.add(choiceLabel to choice.statements)
+                    val onlyJumpLabel = ((choice.statements.children.singleOrNull() as? PtJump)?.target as? PtIdentifier)?.name
+                    if(onlyJumpLabel==null) {
+                        choiceBlocks.add(choiceLabel to choice)
+                    } else {
+                        choiceLabel = onlyJumpLabel
+                    }
                 }
                 for (cv in choice.values.children) {
                     val value = (cv as PtNumber).number.toInt()
@@ -1000,11 +1052,14 @@ $repeatLabel""")
                 }
             }
         }
-        jmp(endLabel)
+
+        if(choiceBlocks.isNotEmpty())
+            jmp(endLabel)
+
         for(choiceBlock in choiceBlocks.withIndex()) {
             out(choiceBlock.value.first)
-            translate(choiceBlock.value.second)
-            if (choiceBlock.index < choiceBlocks.size - 1)
+            translate(choiceBlock.value.second.statements)
+            if (choiceBlock.index < choiceBlocks.size - 1 && !choiceBlock.value.second.isOnlyGotoOrReturn())
                 jmp(endLabel)
         }
         out(endLabel)
@@ -1033,6 +1088,7 @@ $repeatLabel""")
             val target = getJumpTarget(jump)
             require(!target.needsExpressionEvaluation)
             if(target.indirect) {
+                require(!target.indexedX)
                 val complementedInstruction = branchInstruction(stmt.condition, true)
                 out("""
                     $complementedInstruction +
@@ -1084,12 +1140,26 @@ $repeatLabel""")
         else {
             if(evaluateAddressExpression) {
                 val arrayIdx = jump.target as? PtArrayIndexer
-                if(arrayIdx!=null && !arrayIdx.splitWords) {
-                    // if the jump target is an address in a non-split array (like a jump table of only pointers),
-                    // more optimal assembly can be generated using JMP address,X
-                    assignExpressionToRegister(arrayIdx.index, RegisterOrPair.A)
-                    out("  asl  a |  tax")
-                    return JumpTarget(asmSymbolName(arrayIdx.variable), true, true, false)
+                if (arrayIdx!=null) {
+                    val arrayVariable = arrayIdx.variable ?: TODO("support for ptr indexing ${arrayIdx.position}")
+                    if (isTargetCpu(CpuType.CPU65C02)) {
+                        if (!arrayIdx.splitWords) {
+                            // if the jump target is an address in a non-split array (like a jump table of only pointers),
+                            // on the 65c02, more optimal assembly can be generated using JMP (address,X)
+                            assignExpressionToRegister(arrayIdx.index, RegisterOrPair.A)
+                            out("  asl  a |  tax")
+                            return JumpTarget(asmSymbolName(arrayVariable), true, true, false)
+                        } else {
+                            // print a message when more optimal code is possible for 65C02 cpu
+                            val variable = symbolTable.lookup(arrayVariable.name)!!
+                            if(variable is StStaticVariable && variable.length!!<=128u)
+                                errors.info("the jump address array is @split, but @nosplit would create more efficient code here", jump.position)
+                        }
+                    } else {
+                        // print a message when more optimal code is possible for 6502 cpu
+                        if(!arrayIdx.splitWords)
+                            errors.info("the jump address array is @nosplit, but @split would create more efficient code here", jump.position)
+                    }
                 }
                 // we can do the address evaluation right now and just use a temporary pointer variable
                 assignExpressionToVariable(jump.target, "P8ZP_SCRATCH_W1", DataType.UWORD)
@@ -1101,18 +1171,20 @@ $repeatLabel""")
     }
 
     private fun translate(ret: PtReturn) {
-        val returnvalue = ret.children.singleOrNull()
+        val returnvalue = ret.children.singleOrNull() as? PtExpression
         val sub = ret.definingSub()!!
         val returnRegs = sub.returnsWhatWhere()
 
         if(returnvalue!=null) {
-            if (sub.returns.single().isNumericOrBool) {
-                assignExpressionToRegister(returnvalue as PtExpression, returnRegs.single().first.registerOrPair!!)
+            val returnDt = sub.signature.returns.single()
+            if (returnDt.isNumericOrBool || returnDt.isPointer) {
+                assignExpressionToRegister(returnvalue, returnRegs.single().first.registerOrPair!!)
             }
             else {
                 // all else take its address and assign that also to AY register pair
-                val addrofValue = PtAddressOf(returnvalue.position)
-                addrofValue.add(returnvalue as PtIdentifier)
+                val addrOfDt = returnvalue.type.typeForAddressOf(false)
+                val addrofValue = PtAddressOf(addrOfDt, false, returnvalue.position)
+                addrofValue.add(returnvalue)
                 addrofValue.parent = ret.parent
                 assignmentAsmGen.assignExpressionToRegister(addrofValue, returnRegs.single().first.registerOrPair!!, false)
             }
@@ -1239,11 +1311,11 @@ $repeatLabel""")
             return null
         val leftDt = left.type
         val rightDt = right.type
-        if(leftDt.isUnsignedWord && rightDt.isUnsignedByte)
+        if((leftDt.isUnsignedWord || leftDt.isPointer) && rightDt.isUnsignedByte)
             return Pair(left, right)
         if(leftDt.isUnsignedByte && rightDt.isUnsignedWord)
             return Pair(right, left)
-        if(leftDt.isUnsignedWord && rightDt.isUnsignedWord) {
+        if((leftDt.isUnsignedWord || leftDt.isPointer) && rightDt.isUnsignedWord) {
             // could be that the index was a constant numeric byte but converted to word, check that
             val constIdx = right as? PtNumber
             if(constIdx!=null && constIdx.number.toInt()>=0 && constIdx.number.toInt()<=255) {
@@ -1279,9 +1351,7 @@ $repeatLabel""")
         }
 
         if(addressExpr.operator=="+") {
-            val ptrAndIndex = pointerViaIndexRegisterPossible(addressExpr, false)
-            if (ptrAndIndex == null) return false
-
+            val ptrAndIndex = pointerViaIndexRegisterPossible(addressExpr) ?: return false
             if(write) {
 
                 // WRITING TO pointer + offset
@@ -1291,8 +1361,10 @@ $repeatLabel""")
                 if(addrOf!=null && constOffset!=null) {
                     if(addrOf.isFromArrayElement) {
                         TODO("address-of array element $addrOf")
+                    } else if(addrOf.dereference!=null) {
+                        throw AssemblyError("write &dereference, makes no sense at ${addrOf.position}")
                     } else {
-                        out("  sta  ${asmSymbolName(addrOf.identifier)}+${constOffset}")
+                        out("  sta  ${asmSymbolName(addrOf.identifier!!)}+${constOffset}")
                         return true
                     }
                 }
@@ -1331,8 +1403,10 @@ $repeatLabel""")
             if(addrOf!=null && constOffset!=null) {
                 if(addrOf.isFromArrayElement) {
                     TODO("address-of array element $addrOf")
+                } else if(addrOf.dereference!=null) {
+                    TODO("read &dereference")
                 } else {
-                    out("  lda  ${asmSymbolName(addrOf.identifier)}+${constOffset}")
+                    out("  lda  ${asmSymbolName(addrOf.identifier!!)}+${constOffset}")
                     return true
                 }
             }
@@ -1369,9 +1443,7 @@ $repeatLabel""")
         }
 
         else if(addressExpr.operator=="-") {
-            val ptrAndIndex = pointerViaIndexRegisterPossible(addressExpr, true)
-            if (ptrAndIndex == null) return false
-
+            val ptrAndIndex = pointerViaIndexRegisterPossible(addressExpr, true) ?: return false
             if(write) {
 
                 // WRITING TO pointer - offset
@@ -1381,8 +1453,10 @@ $repeatLabel""")
                 if(addrOf!=null && constOffset!=null) {
                     if(addrOf.isFromArrayElement) {
                         TODO("address-of array element $addrOf")
+                    } else if(addrOf.dereference!=null) {
+                        throw AssemblyError("write &dereference, makes no sense at ${addrOf.position}")
                     } else {
-                        out("  sta  ${asmSymbolName(addrOf.identifier)}-${constOffset}")
+                        out("  sta  ${asmSymbolName(addrOf.identifier!!)}-${constOffset}")
                         return true
                     }
                 }
@@ -1412,8 +1486,10 @@ $repeatLabel""")
                 if(addrOf!=null && constOffset!=null) {
                     if(addrOf.isFromArrayElement) {
                         TODO("address-of array element $addrOf")
+                    } else if(addrOf.dereference!=null) {
+                        TODO("read &dereference")
                     } else {
-                        out("  lda  ${asmSymbolName(addrOf.identifier)}-${constOffset}")
+                        out("  lda  ${asmSymbolName(addrOf.identifier!!)}-${constOffset}")
                         return true
                     }
                 }
@@ -1444,7 +1520,15 @@ $repeatLabel""")
         val node = stScope.astNode
         if(node is PtSubroutineParameter)
             return node
-        return node!!.definingSub()?.parameters?.singleOrNull { it.name===name }
+        val params = node!!.definingSub()?.signature?.children
+        if(params!=null) {
+            for(param in params) {
+                param as PtSubroutineParameter
+                if(param.scopedName==name)
+                    return param
+            }
+        }
+        return null
     }
 
     internal fun assignByteOperandsToAAndVar(left: PtExpression, right: PtExpression, rightVarName: String) {
@@ -1549,6 +1633,51 @@ $repeatLabel""")
         return "$GENERATED_LABEL_PREFIX${generatedLabelSequenceNumber}_$postfix"
     }
 
+    internal fun createTempVarReused(dt: BaseDataType, preferZeropage: Boolean, stmt: PtNode): String {
+        val scope = stmt.definingISub()!!
+        val asmInfo = subroutineExtra(scope)
+        var parent = stmt.parent
+        while(parent !is PtProgram) {
+            if(parent is PtRepeatLoop || parent is PtForLoop)
+                break
+            parent = parent.parent
+        }
+        val isNested = parent is PtRepeatLoop || parent is PtForLoop
+
+        if(!isNested) {
+            // we can re-use a counter var from the subroutine if it already has one for that datatype
+            val existingVar = asmInfo.extraVars.firstOrNull { it.first==dt && it.second.endsWith("tempv") }
+            if(existingVar!=null) {
+                if(!preferZeropage || existingVar.third!=null) {
+                    // println("reuse temp counter var: $dt ${existingVar.second}  @${stmt.position}")
+                    return existingVar.second
+                }
+            }
+        }
+
+        val counterVar = makeLabel("tempv")
+        // println("new temp counter var: $dt $counterVar  @${stmt.position}")
+        when {
+            dt.isIntegerOrBool -> {
+                if(preferZeropage) {
+                    val result = zeropage.allocate(counterVar, DataType.forDt(dt), null, stmt.position, errors)
+                    result.fold(
+                        success = { (address, _, _) -> asmInfo.extraVars.add(Triple(dt, counterVar, address)) },
+                        failure = { asmInfo.extraVars.add(Triple(dt, counterVar, null)) }  // allocate normally
+                    )
+                } else {
+                    asmInfo.extraVars.add(Triple(dt, counterVar, null))  // allocate normally
+                }
+                return counterVar
+            }
+            dt == BaseDataType.FLOAT -> {
+                asmInfo.extraVars.add(Triple(dt, counterVar, null)) // allocate normally, floats never on zeropage
+                return counterVar
+            }
+            else -> throw AssemblyError("invalid dt")
+        }
+    }
+
     internal fun assignConstFloatToPointerAY(number: PtNumber) {
         val floatConst = allocator.getFloatAsmConst(number.number)
         out("""
@@ -1569,7 +1698,7 @@ $repeatLabel""")
         val compare = if(useSbc) "sec |  sbc" else "cmp"
         fun cmpViaScratch() {
             if(assignmentAsmGen.directIntoY(value)) {
-                assignExpressionToRegister(value, RegisterOrPair.Y, false)
+                assignExpressionToRegister(value, RegisterOrPair.Y)
                 out("  sty  P8ZP_SCRATCH_REG")
             } else {
                 out("  pha")
@@ -1585,7 +1714,9 @@ $repeatLabel""")
                 if(constIndex!=null) {
                     val offset = program.memsizer.memorySize(value.type, constIndex)
                     if(offset<256) {
-                        return out("  ldy  #$offset |  $compare  ${asmVariableName(value.variable)},y")
+                        if(value.variable==null)
+                            TODO("support for ptr indexing ${value.position}")
+                        return out("  ldy  #$offset |  $compare  ${asmVariableName(value.variable!!)},y")
                     }
                 }
                 cmpViaScratch()
@@ -1628,7 +1759,7 @@ $repeatLabel""")
     }
 
     internal fun assignConditionValueToRegisterAndTest(condition: PtExpression) {
-        assignExpressionToRegister(condition, RegisterOrPair.A, false)
+        assignExpressionToRegister(condition, RegisterOrPair.A)
         when(condition) {
             is PtNumber,
             is PtBool,

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

@@ -408,7 +408,7 @@ private fun optimizeStoreLoadSame(
                     // a branch instruction follows, we can only remove the load instruction if
                     // another load instruction of the same register precedes the store instruction
                     // (otherwise wrong cpu flags are used)
-                    val loadinstruction = second.substring(0, 3)
+                    val loadinstruction = second.take(3)
                     lines[0].value.trimStart().startsWith(loadinstruction)
                 }
                 else {
@@ -508,9 +508,11 @@ private fun optimizeIncDec(linesByFour: Sequence<List<IndexedValue<String>>>): L
 
 private fun optimizeJsrRtsAndOtherCombinations(linesByFour: Sequence<List<IndexedValue<String>>>): List<Modification> {
     // jsr Sub + rts -> jmp Sub
+    // jmp Sub + rts -> jmp Sub
     // rts + jmp -> remove jmp
     // rts + bxx -> remove bxx
     // lda  + cmp #0 -> remove cmp,  same for cpy and cpx.
+    // bra/jmp + bra/jmp -> remove second bra/jmp   (bra bra / jmp jmp are not removed because this is likely a jump table!)
     // and some other optimizations.
 
     val mods = mutableListOf<Modification>()
@@ -520,7 +522,10 @@ private fun optimizeJsrRtsAndOtherCombinations(linesByFour: Sequence<List<Indexe
         val third = lines[2].value
 
         if(!haslabel(second)) {
-            if ((" jsr" in first || "\tjsr" in first ) && (" rts" in second || "\trts" in second)) {
+            if ((" jmp" in first || "\tjmp" in first ) && (" rts" in second || "\trts" in second)) {
+                mods += Modification(lines[1].index, true, null)
+            }
+            else if ((" jsr" in first || "\tjsr" in first ) && (" rts" in second || "\trts" in second)) {
                 if("floats.pushFAC" !in first && "floats.popFAC" !in first) {       // these 2 routines depend on being called with JSR!!
                     mods += Modification(lines[0].index, false, lines[0].value.replace("jsr", "jmp"))
                     mods += Modification(lines[1].index, true, null)
@@ -563,6 +568,15 @@ private fun optimizeJsrRtsAndOtherCombinations(linesByFour: Sequence<List<Indexe
                     }
                 }
             }
+
+            // only remove bra followed by jmp or jmp followed by bra
+            // bra bra or jmp jmp is likely part of a jump table, which should keep all entries!
+            if((" bra" in first || "\tbra" in first) && (" jmp" in second || "\tjmp" in second)) {
+                mods.add(Modification(lines[1].index, true, null))
+            }
+            if((" jmp" in first || "\tjmp" in first) && (" bra" in second || "\tbra" in second)) {
+                mods.add(Modification(lines[1].index, true, null))
+            }
         }
 
         /*

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

@@ -28,6 +28,14 @@ internal class AssemblyProgram(
 
         val assemblerCommand: List<String>
 
+        fun addRemainingOptions(command: MutableList<String>, program: Path, assembly: Path): List<String> {
+            if(options.compTarget.additionalAssemblerOptions.isNotEmpty())
+                command.addAll(options.compTarget.additionalAssemblerOptions)
+
+            command.addAll(listOf("--output", program.toString(), assembly.toString()))
+            return command
+        }
+
         when(options.output) {
             OutputType.PRG -> {
                 // CBM machines .prg generation.
@@ -47,8 +55,7 @@ internal class AssemblyProgram(
                     command.add("--list=$listFile")
                 }
 
-                command.addAll(listOf("--output", prgFile.toString(), assemblyFile.toString()))
-                assemblerCommand = command
+                assemblerCommand = addRemainingOptions(command, prgFile, assemblyFile)
                 if(!options.quiet)
                     println("\nCreating prg for target ${compTarget.name}.")
             }
@@ -69,8 +76,7 @@ internal class AssemblyProgram(
                 if(options.asmListfile)
                     command.add("--list=$listFile")
 
-                command.addAll(listOf("--output", xexFile.toString(), assemblyFile.toString()))
-                assemblerCommand = command
+                assemblerCommand = addRemainingOptions(command,xexFile, assemblyFile)
                 if(!options.quiet)
                     println("\nCreating xex for target ${compTarget.name}.")
             }
@@ -90,8 +96,7 @@ internal class AssemblyProgram(
                 if(options.asmListfile)
                     command.add("--list=$listFile")
 
-                command.addAll(listOf("--output", binFile.toString(), assemblyFile.toString()))
-                assemblerCommand = command
+                assemblerCommand = addRemainingOptions(command, binFile, assemblyFile)
                 if(!options.quiet)
                     println("\nCreating raw binary for target ${compTarget.name}.")
             }
@@ -122,14 +127,10 @@ internal class AssemblyProgram(
                     command.add("--nostart")       // should be headerless bin, because basic has problems doing a normal LOAD"lib",8,1 - need to use BLOAD
                 }
 
-                command.addAll(listOf("--output", binFile.toString(), assemblyFile.toString()))
-                assemblerCommand = command
+                assemblerCommand = addRemainingOptions(command, binFile, assemblyFile)
             }
         }
 
-        if(options.compTarget.additionalAssemblerOptions!=null)
-            assemblerCommand.add(options.compTarget.additionalAssemblerOptions!!)
-
         val proc = ProcessBuilder(assemblerCommand)
         if(!options.quiet)
             proc.inheritIO()

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

@@ -1,5 +1,6 @@
 package prog8.codegen.cpu6502
 
+import prog8.code.SymbolTable
 import prog8.code.ast.*
 import prog8.code.core.*
 import prog8.codegen.cpu6502.assignment.*
@@ -46,6 +47,7 @@ internal class BuiltinFunctionsAsmGen(private val program: PtProgram,
             "memory" -> funcMemory(fcall, discardResult, resultRegister)
             "peekw" -> funcPeekW(fcall, resultRegister)
             "peekf" -> funcPeekF(fcall, resultRegister)
+            "peekbool" -> funcPeekBool(fcall, resultRegister)
             "peek" -> throw AssemblyError("peek() should have been replaced by @()")
             "pokew" -> funcPokeW(fcall)
             "pokef" -> funcPokeF(fcall)
@@ -53,19 +55,21 @@ internal class BuiltinFunctionsAsmGen(private val program: PtProgram,
                 val memread = PtMemoryByte(fcall.position)
                 memread.add(fcall.args[0])
                 memread.parent = fcall
-                asmgen.assignExpressionToRegister(memread, RegisterOrPair.A, false)
+                asmgen.assignExpressionToRegister(memread, RegisterOrPair.A)
                 asmgen.out("  pha")
                 val memtarget = AsmAssignTarget(TargetStorageKind.MEMORY, asmgen, DataType.UBYTE, fcall.definingISub(), fcall.position, memory=memread)
                 asmgen.assignExpressionTo(fcall.args[1], memtarget)
                 asmgen.out("  pla")
             }
             "poke" -> throw AssemblyError("poke() should have been replaced by @()")
+            "pokebool" -> funcPokeBool(fcall)
             "rsave" -> funcRsave()
             "rrestore" -> funcRrestore()
             "cmp" -> funcCmp(fcall)
             "callfar" -> funcCallFar(fcall, resultRegister)
             "callfar2" -> funcCallFar2(fcall, resultRegister)
             "call" -> funcCall(fcall)
+            "prog8_lib_structalloc" -> funcStructAlloc(fcall, discardResult, resultRegister)
             "prog8_lib_stringcompare" -> funcStringCompare(fcall, resultRegister)
             "prog8_lib_square_byte" -> funcSquare(fcall, BaseDataType.UBYTE, resultRegister)
             "prog8_lib_square_word" -> funcSquare(fcall, BaseDataType.UWORD, resultRegister)
@@ -380,8 +384,9 @@ internal class BuiltinFunctionsAsmGen(private val program: PtProgram,
             throw AssemblyError("should not discard result of memory allocation at $fcall")
         val name = (fcall.args[0] as PtString).value
         require(name.all { it.isLetterOrDigit() || it=='_' }) {"memory name should be a valid symbol name ${fcall.position}"}
+
         val slabname = PtIdentifier("prog8_slabs.prog8_memoryslab_$name", DataType.UWORD, fcall.position)
-        val addressOf = PtAddressOf(fcall.position)
+        val addressOf = PtAddressOf(DataType.pointer(BaseDataType.UBYTE), false, fcall.position)
         addressOf.add(slabname)
         addressOf.parent = fcall
         val src = AsmAssignSource(SourceStorageKind.EXPRESSION, program, asmgen, DataType.UWORD, expression = addressOf)
@@ -390,6 +395,21 @@ internal class BuiltinFunctionsAsmGen(private val program: PtProgram,
         asmgen.translateNormalAssignment(assign, fcall.definingISub())
     }
 
+    private fun funcStructAlloc(fcall: PtBuiltinFunctionCall, discardResult: Boolean, resultRegister: RegisterOrPair?) {
+        if(discardResult)
+            throw AssemblyError("should not discard result of struct allocation at $fcall")
+        // ... don't need to pay attention to args here because struct instance is put together elsewhere we just have to get a pointer to it
+        val slabname = SymbolTable.labelnameForStructInstance(fcall)
+        val addressOf = PtAddressOf(fcall.type, true, fcall.position)
+        addressOf.add(PtIdentifier(slabname, fcall.type, fcall.position))
+        addressOf.parent = fcall
+        val src = AsmAssignSource(SourceStorageKind.EXPRESSION, program, asmgen, fcall.type, expression = addressOf)
+        val target = AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.AY, false, fcall.position, null, asmgen)
+        val assign = AsmAssignment(src, listOf(target), program.memsizer, fcall.position)
+        asmgen.translateNormalAssignment(assign, fcall.definingISub())
+    }
+
+
     private fun funcSqrt(fcall: PtBuiltinFunctionCall, resultRegister: RegisterOrPair?, scope: IPtSubroutine?) {
         translateArguments(fcall, scope)
         when(fcall.args[0].type.base) {
@@ -415,8 +435,11 @@ internal class BuiltinFunctionsAsmGen(private val program: PtProgram,
             BaseDataType.UBYTE -> {
                 when (what) {
                     is PtArrayIndexer -> {
+                        if(what.variable==null)
+                            TODO("support for ptr indexing ${what.position}")
+
                         asmgen.loadScaledArrayIndexIntoRegister(what, CpuRegister.X)
-                        val varname = asmgen.asmVariableName(what.variable)
+                        val varname = asmgen.asmVariableName(what.variable!!)
                         asmgen.out("  lda  ${varname},x |  lsr  a |  bcc  + |  ora  #$80 |+  |  sta  ${varname},x")
                     }
                     is PtMemoryByte -> {
@@ -438,8 +461,10 @@ internal class BuiltinFunctionsAsmGen(private val program: PtProgram,
             BaseDataType.UWORD -> {
                 when (what) {
                     is PtArrayIndexer -> {
+                        if(what.variable==null)
+                            TODO("support for ptr indexing ${what.position}")
                         asmgen.loadScaledArrayIndexIntoRegister(what, CpuRegister.X)
-                        val varname = asmgen.asmVariableName(what.variable)
+                        val varname = asmgen.asmVariableName(what.variable!!)
                         if(what.splitWords)
                             asmgen.out("  lsr  ${varname}_msb,x |  ror  ${varname}_lsb,x |  bcc  + |  lda  ${varname}_msb,x |  ora  #$80 |  sta  ${varname}_msb,x |+ ")
                         else
@@ -465,7 +490,10 @@ internal class BuiltinFunctionsAsmGen(private val program: PtProgram,
                         if(!what.index.isSimple()) asmgen.out("  php")   // save Carry
                         asmgen.loadScaledArrayIndexIntoRegister(what, CpuRegister.X)
                         if(!what.index.isSimple()) asmgen.out("  plp")
-                        val varname = asmgen.asmVariableName(what.variable)
+
+                        if(what.variable==null)
+                            TODO("support for ptr indexing ${what.position}")
+                        val varname = asmgen.asmVariableName(what.variable!!)
                         asmgen.out("  ror  ${varname},x")
                     }
                     is PtMemoryByte -> {
@@ -498,7 +526,9 @@ internal class BuiltinFunctionsAsmGen(private val program: PtProgram,
                         if(!what.index.isSimple()) asmgen.out("  php")   // save Carry
                         asmgen.loadScaledArrayIndexIntoRegister(what, CpuRegister.X)
                         if(!what.index.isSimple()) asmgen.out("  plp")
-                        val varname = asmgen.asmVariableName(what.variable)
+                        if(what.variable==null)
+                            TODO("support for ptr indexing ${what.position}")
+                        val varname = asmgen.asmVariableName(what.variable!!)
                         if(what.splitWords)
                             asmgen.out("  ror  ${varname}_msb,x |  ror  ${varname}_lsb,x")
                         else
@@ -521,8 +551,10 @@ internal class BuiltinFunctionsAsmGen(private val program: PtProgram,
             BaseDataType.UBYTE -> {
                 when (what) {
                     is PtArrayIndexer -> {
+                        if(what.variable==null)
+                            TODO("support for ptr indexing ${what.position}")
                         asmgen.loadScaledArrayIndexIntoRegister(what, CpuRegister.X)
-                        val varname = asmgen.asmVariableName(what.variable)
+                        val varname = asmgen.asmVariableName(what.variable!!)
                         asmgen.out("  lda  ${varname},x |  cmp  #$80 |  rol  a |  sta  ${varname},x")
                     }
                     is PtMemoryByte -> {
@@ -545,7 +577,9 @@ internal class BuiltinFunctionsAsmGen(private val program: PtProgram,
                 when (what) {
                     is PtArrayIndexer -> {
                         asmgen.loadScaledArrayIndexIntoRegister(what, CpuRegister.X)
-                        val varname = asmgen.asmVariableName(what.variable)
+                        if(what.variable==null)
+                            TODO("support for ptr indexing ${what.position}")
+                        val varname = asmgen.asmVariableName(what.variable!!)
                         if(what.splitWords)
                             asmgen.out("  asl  ${varname}_lsb,x |  rol  ${varname}_msb,x |  bcc  + |  inc  ${varname}_lsb,x |+")
                         else
@@ -571,7 +605,9 @@ internal class BuiltinFunctionsAsmGen(private val program: PtProgram,
                         if(!what.index.isSimple()) asmgen.out("  php")   // save Carry
                         asmgen.loadScaledArrayIndexIntoRegister(what, CpuRegister.X)
                         if(!what.index.isSimple()) asmgen.out("  plp")
-                        val varname = asmgen.asmVariableName(what.variable)
+                        if(what.variable==null)
+                            TODO("support for ptr indexing ${what.position}")
+                        val varname = asmgen.asmVariableName(what.variable!!)
                         asmgen.out("  rol  ${varname},x")
                     }
                     is PtMemoryByte -> {
@@ -604,7 +640,9 @@ internal class BuiltinFunctionsAsmGen(private val program: PtProgram,
                         if(!what.index.isSimple()) asmgen.out("  php")   // save Carry
                         asmgen.loadScaledArrayIndexIntoRegister(what, CpuRegister.X)
                         if(!what.index.isSimple()) asmgen.out("  plp")
-                        val varname = asmgen.asmVariableName(what.variable)
+                        if(what.variable==null)
+                            TODO("support for ptr indexing ${what.position}")
+                        val varname = asmgen.asmVariableName(what.variable!!)
                         if(what.splitWords)
                             asmgen.out("  rol  ${varname}_lsb,x |  rol  ${varname}_msb,x")
                         else
@@ -633,7 +671,7 @@ internal class BuiltinFunctionsAsmGen(private val program: PtProgram,
                 val elementSize: Int
                 val msbAdd: Int
                 if(indexer.splitWords) {
-                    val arrayVariable = indexer.variable
+                    val arrayVariable = indexer.variable ?: TODO("support for ptr indexing ${indexer.position}")
                     indexer.children[0] = PtIdentifier(arrayVariable.name + if(msb) "_msb" else "_lsb", DataType.arrayFor(BaseDataType.UBYTE, false), arrayVariable.position)
                     indexer.children[0].parent = indexer
                     elementSize = 1
@@ -676,7 +714,7 @@ internal class BuiltinFunctionsAsmGen(private val program: PtProgram,
         if(fcall.args[1].asConstInteger() == 0) {
             assignAsmGen.assignConstantByte(target, 0)
         } else {
-            asmgen.assignExpressionToRegister(fcall.args[1], RegisterOrPair.A, false)
+            asmgen.assignExpressionToRegister(fcall.args[1], RegisterOrPair.A)
             assignAsmGen.assignRegisterByte(target, CpuRegister.A, false, false)
         }
     }
@@ -739,7 +777,7 @@ internal class BuiltinFunctionsAsmGen(private val program: PtProgram,
                 asmgen.assignConstFloatToPointerAY(number)
             }
             else -> {
-                val tempvar = asmgen.getTempVarName(BaseDataType.FLOAT)
+                val tempvar = asmgen.createTempVarReused(BaseDataType.FLOAT, false, fcall)
                 asmgen.assignExpressionToVariable(fcall.args[1], tempvar, DataType.FLOAT)
                 asmgen.assignExpressionToRegister(fcall.args[0], RegisterOrPair.AY)
                 asmgen.out("""
@@ -754,6 +792,58 @@ internal class BuiltinFunctionsAsmGen(private val program: PtProgram,
         }
     }
 
+    private fun funcPokeBool(fcall: PtBuiltinFunctionCall) {
+        when(val addrExpr = fcall.args[0]) {
+            is PtNumber -> {
+                asmgen.assignExpressionToRegister(fcall.args[1], RegisterOrPair.A)
+                val addr = addrExpr.number.toHex()
+                asmgen.out("  sta  $addr")
+                return
+            }
+            is PtIdentifier -> {
+                val varname = asmgen.asmVariableName(addrExpr)
+                if(asmgen.isZpVar(addrExpr)) {
+                    // pointervar is already in the zero page, no need to copy
+                    asmgen.assignExpressionToRegister(fcall.args[1], RegisterOrPair.A)
+                    if (asmgen.isTargetCpu(CpuType.CPU65C02))
+                        asmgen.out("  sta  ($varname)")
+                    else
+                        asmgen.out("  ldy  #0 |  sta  ($varname),y")
+                    return
+                }
+            }
+            is PtBinaryExpression -> {
+                val result = asmgen.pointerViaIndexRegisterPossible(addrExpr)
+                val pointer = result?.first as? PtIdentifier
+                if(result!=null && pointer!=null && asmgen.isZpVar(pointer)) {
+                    // can do ZP,Y indexing
+                    val varname = asmgen.asmVariableName(pointer)
+                    asmgen.assignExpressionToRegister(result.second, RegisterOrPair.Y)
+                    asmgen.saveRegisterStack(CpuRegister.Y, false)
+                    asmgen.assignExpressionToRegister(fcall.args[1], RegisterOrPair.A)
+                    asmgen.restoreRegisterStack(CpuRegister.Y, true)
+                    asmgen.out("  sta  ($varname),y")
+                    return
+                }
+            }
+            else -> { /* fall through */ }
+        }
+
+        // fall through method:
+        if(fcall.args[1].isSimple()) {
+            asmgen.assignExpressionToVariable(fcall.args[0], "P8ZP_SCRATCH_W1", DataType.UWORD)
+            asmgen.assignExpressionToRegister(fcall.args[1], RegisterOrPair.A)
+        }  else {
+            asmgen.pushCpuStack(BaseDataType.UBYTE, fcall.args[1])
+            asmgen.assignExpressionToVariable(fcall.args[0], "P8ZP_SCRATCH_W1", DataType.UWORD)
+            asmgen.restoreRegisterStack(CpuRegister.A, false)
+        }
+        if(asmgen.isTargetCpu(CpuType.CPU65C02))
+            asmgen.out("  sta  (P8ZP_SCRATCH_W1)")
+        else
+            asmgen.out("  ldy  #0 |  sta  (P8ZP_SCRATCH_W1),y")
+    }
+
     private fun funcPokeW(fcall: PtBuiltinFunctionCall) {
         when(val addrExpr = fcall.args[0]) {
             is PtNumber -> {
@@ -815,7 +905,49 @@ internal class BuiltinFunctionsAsmGen(private val program: PtProgram,
         asmgen.out("  jsr  floats.MOVFM")
         if(resultRegister!=null) {
             assignAsmGen.assignFAC1float(
-                AsmAssignTarget(TargetStorageKind.REGISTER, asmgen, DataType.FLOAT, fcall.definingISub(), fcall.position, null, null, null, resultRegister, null))
+                AsmAssignTarget(TargetStorageKind.REGISTER, asmgen, DataType.FLOAT, fcall.definingISub(), register=resultRegister, position=fcall.position))
+        }
+    }
+
+    private fun funcPeekBool(fcall: PtBuiltinFunctionCall, resultRegister: RegisterOrPair?) {
+        fun fallback() {
+            asmgen.assignExpressionToRegister(fcall.args[0], RegisterOrPair.AY)
+            asmgen.out("  jsr  prog8_lib.func_peek")
+        }
+        when(val addrExpr = fcall.args[0]) {
+            is PtNumber -> {
+                val addr = addrExpr.number.toHex()
+                asmgen.out("  lda  $addr")
+            }
+            is PtIdentifier -> {
+                val varname = asmgen.asmVariableName(addrExpr)
+                if(asmgen.isZpVar(addrExpr)) {
+                    // pointervar is already in the zero page, no need to copy
+                    if (asmgen.isTargetCpu(CpuType.CPU65C02))
+                        asmgen.out("  lda  ($varname)")
+                    else
+                        asmgen.out("  ldy  #0 |  lda  ($varname),y")
+                } else fallback()
+            }
+            is PtBinaryExpression -> {
+                val result = asmgen.pointerViaIndexRegisterPossible(addrExpr)
+                val pointer = result?.first as? PtIdentifier
+                if(result!=null && pointer!=null && asmgen.isZpVar(pointer)) {
+                    // can do ZP,Y indexing
+                    val varname = asmgen.asmVariableName(pointer)
+                    asmgen.assignExpressionToRegister(result.second, RegisterOrPair.Y)
+                    asmgen.out("  lda  ($varname),y")
+                } else fallback()
+            }
+            else -> fallback()
+        }
+
+        when(resultRegister ?: RegisterOrPair.A) {
+            RegisterOrPair.A -> {}
+            RegisterOrPair.X -> asmgen.out("  tax")
+            RegisterOrPair.Y -> asmgen.out("  tay")
+            in Cx16VirtualRegisters -> asmgen.out("  sta  cx16.${resultRegister.toString().lowercase()}")
+            else -> throw AssemblyError("invalid reg")
         }
     }
 
@@ -1112,7 +1244,9 @@ internal class BuiltinFunctionsAsmGen(private val program: PtProgram,
             if(arg is PtArrayIndexer && resultRegister in arrayOf(null, RegisterOrPair.A, RegisterOrPair.Y, RegisterOrPair.X)) {
                 // just read the msb byte out of the word array
                 if(arg.splitWords) {
-                    val arrayVar = asmgen.asmVariableName(arg.variable)+"_msb"
+                    if(arg.variable==null)
+                        TODO("support for ptr indexing ${arg.position}")
+                    val arrayVar = asmgen.asmVariableName(arg.variable!!)+"_msb"
                     when(resultRegister) {
                         null, RegisterOrPair.A -> {
                             asmgen.loadScaledArrayIndexIntoRegister(arg, CpuRegister.Y)
@@ -1129,7 +1263,9 @@ internal class BuiltinFunctionsAsmGen(private val program: PtProgram,
                         else -> throw AssemblyError("invalid reg")
                     }
                 } else {
-                    val arrayVar = asmgen.asmVariableName(arg.variable)
+                    if(arg.variable==null)
+                        TODO("support for ptr indexing ${arg.position}")
+                    val arrayVar = asmgen.asmVariableName(arg.variable!!)
                     when(resultRegister) {
                         null, RegisterOrPair.A -> {
                             asmgen.loadScaledArrayIndexIntoRegister(arg, CpuRegister.Y)
@@ -1211,7 +1347,10 @@ internal class BuiltinFunctionsAsmGen(private val program: PtProgram,
         } else {
             if(arg is PtArrayIndexer && resultRegister in arrayOf(null, RegisterOrPair.A, RegisterOrPair.Y, RegisterOrPair.X)) {
                 // just read the lsb byte out of the word array
-                val arrayVar = if(arg.splitWords) asmgen.asmVariableName(arg.variable)+"_lsb" else asmgen.asmVariableName(arg.variable)
+                if(arg.variable==null)
+                    TODO("support for ptr indexing ${arg.position}")
+
+                val arrayVar = if(arg.splitWords) asmgen.asmVariableName(arg.variable!!)+"_lsb" else asmgen.asmVariableName(arg.variable!!)
                 when(resultRegister) {
                     null, RegisterOrPair.A -> {
                         asmgen.loadScaledArrayIndexIntoRegister(arg, CpuRegister.Y)
@@ -1276,7 +1415,7 @@ internal class BuiltinFunctionsAsmGen(private val program: PtProgram,
         fun getSourceForFloat(value: PtExpression): AsmAssignSource {
             return when (value) {
                 is PtIdentifier -> {
-                    val addr = PtAddressOf(value.position)
+                    val addr = PtAddressOf(DataType.pointer(BaseDataType.FLOAT), false, value.position)
                     addr.add(value)
                     addr.parent = call
                     AsmAssignSource.fromAstSource(addr, program, asmgen)
@@ -1290,7 +1429,7 @@ internal class BuiltinFunctionsAsmGen(private val program: PtProgram,
 
                     asmgen.subroutineExtra(scope).usedFloatEvalResultVar2 = true
                     val variable = PtIdentifier(subroutineFloatEvalResultVar2, DataType.FLOAT, value.position)
-                    val addr = PtAddressOf(value.position)
+                    val addr = PtAddressOf(DataType.pointer(BaseDataType.FLOAT), false, value.position)
                     addr.add(variable)
                     addr.parent = call
                     asmgen.assignExpressionToVariable(value, asmgen.asmVariableName(variable), DataType.FLOAT)
@@ -1310,7 +1449,7 @@ internal class BuiltinFunctionsAsmGen(private val program: PtProgram,
                         conv.dt==BaseDataType.FLOAT -> getSourceForFloat(value)
                         conv.dt.isPassByRef -> {
                             // put the address of the argument in AY
-                            val addr = PtAddressOf(value.position)
+                            val addr = PtAddressOf(DataType.forDt(conv.dt).typeForAddressOf(false), false, value.position)
                             addr.add(value)
                             addr.parent = call
                             AsmAssignSource.fromAstSource(addr, program, asmgen)
@@ -1328,7 +1467,7 @@ internal class BuiltinFunctionsAsmGen(private val program: PtProgram,
                         conv.dt==BaseDataType.FLOAT -> getSourceForFloat(value)
                         conv.dt.isPassByRef -> {
                             // put the address of the argument in AY
-                            val addr = PtAddressOf(value.position)
+                            val addr = PtAddressOf(DataType.forDt(conv.dt).typeForAddressOf(false), false,value.position)
                             addr.add(value)
                             addr.parent = call
                             AsmAssignSource.fromAstSource(addr, program, asmgen)

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

@@ -89,8 +89,8 @@ internal class ForLoopsAsmGen(
         if(asmgen.options.romable) {
             // cannot use self-modifying code, cannot use cpu stack (because loop can be interrupted halfway)
             // so we need to store the loop end value in a newly allocated temporary variable
-            val toValueVar = asmgen.getTempVarName(iterableDt.elementType().base)
-            asmgen.assignExpressionToRegister(range.to, RegisterOrPair.A, false)
+            val toValueVar = asmgen.createTempVarReused(iterableDt.elementType().base, false, range)
+            asmgen.assignExpressionToRegister(range.to, RegisterOrPair.A)
             asmgen.out("  sta  $toValueVar")
             // pre-check for end already reached
             if(iterableDt.isSignedByteArray) {
@@ -136,7 +136,7 @@ internal class ForLoopsAsmGen(
 
             // use self-modifying code to store the loop end comparison value
             val modifiedLabel = asmgen.makeLabel("for_modified")
-            asmgen.assignExpressionToRegister(range.to, RegisterOrPair.A, false)
+            asmgen.assignExpressionToRegister(range.to, RegisterOrPair.A)
             // pre-check for end already reached
             if(iterableDt.isSignedByteArray) {
                 asmgen.out("  sta  $modifiedLabel+1")
@@ -186,7 +186,7 @@ $modifiedLabel  cmp  #0         ; modified
         val stepsize = range.step.asConstInteger()!!
 
         val modifiedLabel = asmgen.makeLabel("for_modified")
-        asmgen.assignExpressionToRegister(range.to, RegisterOrPair.A, false)
+        asmgen.assignExpressionToRegister(range.to, RegisterOrPair.A)
         // pre-check for end already reached
         if(iterableDt.isSignedByteArray) {
             asmgen.out("  sta  $modifiedLabel+1")
@@ -296,7 +296,7 @@ $modifiedLabel  cmp  #0     ; modified
         if(asmgen.options.romable) {
             // cannot use self-modifying code, cannot use cpu stack (because loop can be interrupted halfway)
             // so we need to store the loop end value in a newly allocated temporary variable
-            val toValueVar = asmgen.getTempVarName(iterableDt.elementType().base)
+            val toValueVar = asmgen.createTempVarReused(iterableDt.elementType().base, false, range)
             asmgen.assignExpressionToRegister(range.to, RegisterOrPair.AY)
             precheckFromToWord(iterableDt, stepsize, varname, endLabel)
             asmgen.out("  sta  $toValueVar")
@@ -420,6 +420,7 @@ $endLabel""")
         val modifiedLabel2 = asmgen.makeLabel("for_modifiedb")
         asmgen.assignExpressionToRegister(range.to, RegisterOrPair.AY)
         precheckFromToWord(iterableDt, stepsize, varname, endLabel)
+        asmgen.romableError("self-modifying code (forloop over words range)", stmt.position)  // TODO fix romable; there is self-modifying code below
         asmgen.out("""
                 sty  $modifiedLabel+1
                 sta  $modifiedLabel2+1
@@ -442,7 +443,6 @@ $modifiedLabel  sbc  #0    ; modified
                 eor  #$80
 +               bpl  $loopLabel                
 $endLabel""")
-        asmgen.romableError("self-modifying code (forloop over words range)", stmt.position)  // TODO fix romable
     }
 
     private fun precheckFromToWord(iterableDt: DataType, stepsize: Int, fromVar: String, endLabel: String) {
@@ -500,15 +500,15 @@ $endLabel""")
         val endLabel = asmgen.makeLabel("for_end")
         asmgen.loopEndLabels.add(endLabel)
         val iterableName = asmgen.asmVariableName(ident)
-        val numElements = when(val symbol = asmgen.symbolTable.lookup(ident.name)) {
+        val numElements: UInt = when(val symbol = asmgen.symbolTable.lookup(ident.name)) {
             is StStaticVariable -> symbol.length!!
             is StMemVar -> symbol.length!!
-            else -> 0
+            else -> 0u
         }
         when {
             iterableDt.isString -> {
                 if(asmgen.options.romable) {
-                    val indexVar = asmgen.getTempVarName(BaseDataType.UBYTE)
+                    val indexVar = asmgen.createTempVarReused(BaseDataType.UBYTE, false, stmt)
                     asmgen.out("""
                         ldy  #0
                         sty  $indexVar
@@ -539,14 +539,17 @@ $endLabel""")
                 }
             }
             iterableDt.isByteArray || iterableDt.isBoolArray -> {
-                val indexVar = if(asmgen.options.romable) asmgen.getTempVarName(iterableDt.elementType().base) else asmgen.makeLabel("for_index")
+                val indexVar = if(asmgen.options.romable)
+                    asmgen.createTempVarReused(iterableDt.elementType().base, false, stmt)
+                else
+                    asmgen.makeLabel("for_index")
                 asmgen.out("""
                     ldy  #0
 $loopLabel          sty  $indexVar
                     lda  $iterableName,y
                     sta  ${asmgen.asmVariableName(stmt.variable)}""")
                 asmgen.translate(stmt.statements)
-                if(numElements<=255) {
+                if(numElements<=255u) {
                     asmgen.out("""
                         ldy  $indexVar
                         iny
@@ -562,7 +565,7 @@ $loopLabel          sty  $indexVar
                         beq  $endLabel""")
                 }
                 if(!asmgen.options.romable) {
-                    if(numElements>=16) {
+                    if(numElements>=16u) {
                         // allocate index var on ZP if possible, otherwise inline
                         val result = zeropage.allocate(indexVar, DataType.UBYTE, null, stmt.position, asmgen.errors)
                         result.fold(
@@ -576,7 +579,10 @@ $loopLabel          sty  $indexVar
                 asmgen.out(endLabel)
             }
             iterableDt.isSplitWordArray -> {
-                val indexVar = if(asmgen.options.romable) asmgen.getTempVarName(BaseDataType.UBYTE) else asmgen.makeLabel("for_index")
+                val indexVar = if(asmgen.options.romable)
+                    asmgen.createTempVarReused(BaseDataType.UBYTE, false, stmt)
+                else
+                    asmgen.makeLabel("for_index")
                 val loopvarName = asmgen.asmVariableName(stmt.variable)
                 asmgen.out("""
                     ldy  #0
@@ -586,7 +592,7 @@ $loopLabel          sty  $indexVar
                     lda  ${iterableName}_msb,y
                     sta  $loopvarName+1""")
                 asmgen.translate(stmt.statements)
-                if(numElements<=255) {
+                if(numElements<=255u) {
                     asmgen.out("""
                         ldy  $indexVar
                         iny
@@ -602,7 +608,7 @@ $loopLabel          sty  $indexVar
                         beq  $endLabel""")
                 }
                 if(!asmgen.options.romable) {
-                    if(numElements>=16) {
+                    if(numElements>=16u) {
                         // allocate index var on ZP if possible, otherwise inline
                         val result = zeropage.allocate(indexVar, DataType.UBYTE, null, stmt.position, asmgen.errors)
                         result.fold(
@@ -616,8 +622,10 @@ $loopLabel          sty  $indexVar
                 asmgen.out(endLabel)
             }
             iterableDt.isWordArray -> {
-                val length = numElements * 2
-                val indexVar = if(asmgen.options.romable) asmgen.getTempVarName(BaseDataType.UBYTE) else asmgen.makeLabel("for_index")
+                val indexVar = if(asmgen.options.romable)
+                    asmgen.createTempVarReused(BaseDataType.UBYTE, false, stmt)
+                else
+                    asmgen.makeLabel("for_index")
                 val loopvarName = asmgen.asmVariableName(stmt.variable)
                 asmgen.out("""
                     ldy  #0
@@ -627,16 +635,16 @@ $loopLabel          sty  $indexVar
                     lda  $iterableName+1,y
                     sta  $loopvarName+1""")
                 asmgen.translate(stmt.statements)
-                if(length<=127) {
+                if(numElements<=127u) {
                     asmgen.out("""
                         ldy  $indexVar
                         iny
                         iny
-                        cpy  #$length
+                        cpy  #${numElements*2u}
                         beq  $endLabel
                         bne  $loopLabel""")
                 } else {
-                    // length is 128 words, 256 bytes
+                    // array size is 128 words, 256 bytes
                     asmgen.out("""
                         ldy  $indexVar
                         iny
@@ -645,7 +653,7 @@ $loopLabel          sty  $indexVar
                         beq  $endLabel""")
                 }
                 if(!asmgen.options.romable) {
-                    if(length>=16) {
+                    if(numElements>=16u) {
                         // allocate index var on ZP if possible, otherwise inline
                         val result = zeropage.allocate(indexVar, DataType.UBYTE, null, stmt.position, asmgen.errors)
                         result.fold(

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

@@ -21,7 +21,7 @@ internal class FunctionCallAsmGen(private val program: PtProgram, private val as
         // we consider them NOT to be optimized into (possibly different) CPU registers.
         // Just load them in whatever the register spec says.
         return when (params.size) {
-            1 -> params[0].type.isIntegerOrBool && params[0].register == null
+            1 -> params[0].register == null && (params[0].type.isIntegerOrBool || params[0].type.isPointer)
             2 -> params[0].type.isByteOrBool && params[1].type.isByteOrBool && params[0].register == null && params[1].register == null
             else -> false
         }
@@ -36,7 +36,7 @@ internal class FunctionCallAsmGen(private val program: PtProgram, private val as
         val symbol = asmgen.symbolTable.lookup(call.name)!!
         if(symbol.type == StNodeType.LABEL) {
             require(call.void)
-            asmgen.out("  jsr  ${asmgen.asmSymbolName(symbol.scopedName)}")
+            asmgen.out("  jsr  ${asmgen.asmSymbolName(symbol.scopedNameString)}")
             return
         }
 
@@ -139,15 +139,16 @@ internal class FunctionCallAsmGen(private val program: PtProgram, private val as
             }
         }
         else if(sub is PtSub) {
-            if(optimizeIntArgsViaCpuRegisters(sub.parameters)) {
+            val parameters = sub.signature.children.filterIsInstance<PtSubroutineParameter>()
+            if(optimizeIntArgsViaCpuRegisters(parameters)) {
                 // Note that if the args fit into cpu registers, we don't concern ourselves here
                 // if they should be put into regular subroutine parameter variables, or the R0-R15 register variables.
                 // That is now up to the subroutine itself.
                 useCpuRegistersForArgs(call.args, sub)
             } else {
                 // arguments via variables
-                val paramValues = sub.parameters.zip(call.args)
-                val (normalParams, registerParams) = paramValues.partition { it.first.register == null }
+                val paramValues = parameters.zip(call.args)
+                val (normalParams, registerParams) = paramValues.partition { (it.first.register == null) }
                 if (normalParams.isNotEmpty()) {
                     for (p in normalParams)
                         argumentViaVariable(sub, p.first, p.second)
@@ -166,7 +167,7 @@ internal class FunctionCallAsmGen(private val program: PtProgram, private val as
     }
 
     private fun useCpuRegistersForArgs(args: List<PtExpression>, sub: PtSub) {
-        val params = sub.parameters
+        val params = sub.signature.children.filterIsInstance<PtSubroutineParameter>()
         when(params.size) {
             1 -> {
                 val register = if (params[0].type.isByteOrBool) RegisterOrPair.A else RegisterOrPair.AY
@@ -234,9 +235,9 @@ internal class FunctionCallAsmGen(private val program: PtProgram, private val as
                 val param = sub.parameters[it]
                 val arg = call.args[it]
                 registersUsed += if(usesOtherRegistersWhileEvaluating(arg)) {
-                    if(!registersUsed.any{it.statusflag!=null || it.registerOrPair in CpuRegisters})
+                    if(!registersUsed.any{r -> r.statusflag!=null || r.registerOrPair in CpuRegisters})
                         argumentViaRegister(sub, IndexedValue(it, param.second), arg)
-                    else if(registersUsed.any {it.statusflag!=null}) {
+                    else if(registersUsed.any { r-> r.statusflag!=null }) {
                         throw AssemblyError("call argument evaluation problem: can't save cpu statusregister parameter ${call.position}")
                     }
                     else {
@@ -332,14 +333,14 @@ internal class FunctionCallAsmGen(private val program: PtProgram, private val as
             } else {
                 val scope = value.definingISub()
                 val target: AsmAssignTarget =
-                    if(parameter.value.type.isByte && (register==RegisterOrPair.AX || register == RegisterOrPair.AY || register==RegisterOrPair.XY || register in Cx16VirtualRegisters))
+                    if(parameter.value.type.isByte && register.isWord())
                         AsmAssignTarget(TargetStorageKind.REGISTER, asmgen, parameter.value.type, scope, value.position, register = register)
                     else {
                         AsmAssignTarget.fromRegisters(register, parameter.value.type.isSigned, value.position, scope, asmgen)
                     }
                 val src = if(value.type.isPassByRef) {
                     if(value is PtIdentifier) {
-                        val addr = PtAddressOf(Position.DUMMY)
+                        val addr = PtAddressOf(value.type.typeForAddressOf(false), false, Position.DUMMY)
                         addr.add(value)
                         addr.parent = scope as PtNode
                         AsmAssignSource.fromAstSource(addr, program, asmgen).adjustSignedUnsigned(target)

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

@@ -6,11 +6,13 @@ import prog8.code.ast.*
 import prog8.code.core.*
 import prog8.codegen.cpu6502.assignment.AsmAssignTarget
 import prog8.codegen.cpu6502.assignment.AssignmentAsmGen
+import prog8.codegen.cpu6502.assignment.PointerAssignmentsGen
 import prog8.codegen.cpu6502.assignment.TargetStorageKind
 
 internal class IfElseAsmGen(private val program: PtProgram,
                             private val st: SymbolTable,
                             private val asmgen: AsmGen6502Internal,
+                            private val pointergen: PointerAssignmentsGen,
                             private val assignmentAsmGen: AssignmentAsmGen,
                             private val errors: IErrorReporter) {
 
@@ -38,13 +40,12 @@ internal class IfElseAsmGen(private val program: PtProgram,
                 // use a BIT instruction to test for bit 7 or 6 set/clear
                 val (testBitSet, variable, bitmask) = useBIT
                 return translateIfBIT(stmt, jumpAfterIf, testBitSet, variable, bitmask)
-                return
             }
 
             val rightDt = compareCond.right.type
             return when {
                 rightDt.isByteOrBool -> translateIfByte(stmt, jumpAfterIf)
-                rightDt.isWord -> translateIfWord(stmt, compareCond, jumpAfterIf)
+                rightDt.isWord || rightDt.isPointer -> translateIfWord(stmt, compareCond, jumpAfterIf)
                 rightDt.isFloat -> translateIfFloat(stmt, compareCond, jumpAfterIf)
                 else -> throw AssemblyError("weird dt")
             }
@@ -64,6 +65,16 @@ internal class IfElseAsmGen(private val program: PtProgram,
             }
         }
 
+        val dereference = stmt.condition as? PtPointerDeref
+        if(dereference!=null) {
+            val zpPtrVar = pointergen.deref(dereference)
+            pointergen.loadIndirectByte(zpPtrVar)
+            return if (jumpAfterIf != null)
+                translateJumpElseBodies("bne", "beq", jumpAfterIf, stmt.elseScope)
+            else
+                translateIfElseBodies("beq", stmt)
+        }
+
         throw AssemblyError("weird non-boolean condition node type ${stmt.condition} at ${stmt.condition.position}")
     }
 
@@ -87,6 +98,7 @@ internal class IfElseAsmGen(private val program: PtProgram,
                 if(testForBitSet) {
                     if(jumpAfterIf!=null) {
                         val target = asmgen.getJumpTarget(jumpAfterIf)
+                        require(!target.indexedX)
                         branch("bmi", target)
                     }
                     else
@@ -94,6 +106,7 @@ internal class IfElseAsmGen(private val program: PtProgram,
                 } else {
                     if(jumpAfterIf!=null) {
                         val target = asmgen.getJumpTarget(jumpAfterIf)
+                        require(!target.indexedX)
                         branch("bpl", target)
                     }
                     else
@@ -107,6 +120,7 @@ internal class IfElseAsmGen(private val program: PtProgram,
                 if(testForBitSet) {
                     if(jumpAfterIf!=null) {
                         val target = asmgen.getJumpTarget(jumpAfterIf)
+                        require(!target.indexedX)
                         branch("bvs", target)
                     }
                     else
@@ -114,6 +128,7 @@ internal class IfElseAsmGen(private val program: PtProgram,
                 } else {
                     if(jumpAfterIf!=null) {
                         val target = asmgen.getJumpTarget(jumpAfterIf)
+                        require(!target.indexedX)
                         branch("bvc", target)
                     }
                     else
@@ -146,6 +161,93 @@ internal class IfElseAsmGen(private val program: PtProgram,
             translateIfElseBodies("beq", ifElse)
     }
 
+    private fun translateIfElseBodiesSignedByte(elseConditional: String, value: PtExpression, stmt: PtIfElse) {
+        fun branchElse(label: String) {
+            when (elseConditional) {
+                "<" -> {
+                    asmgen.out("""
+                        bvc  +
+                        eor  #$80
++                       bpl  $label""")
+                }
+                ">=" -> {
+                    asmgen.out("""
+                        bvc  +
+                        eor  #$80
++                       bmi  $label""")
+                }
+                else -> throw AssemblyError("wrong conditional $elseConditional")
+            }
+        }
+        val afterIfLabel = asmgen.makeLabel("afterif")
+        asmgen.cmpAwithByteValue(value, true)
+        if(stmt.hasElse()) {
+            // if and else blocks
+            val elseLabel = asmgen.makeLabel("else")
+            branchElse(elseLabel)
+            asmgen.translate(stmt.ifScope)
+            asmgen.jmp(afterIfLabel)
+            asmgen.out(elseLabel)
+            asmgen.translate(stmt.elseScope)
+        } else {
+            // no else block
+            branchElse(afterIfLabel)
+            asmgen.translate(stmt.ifScope)
+        }
+        asmgen.out(afterIfLabel)
+    }
+
+    private fun translateJumpElseBodiesSignedByte(elseConditional: String, value: PtExpression, jump: PtJump, elseBlock: PtNodeGroup) {
+        fun branchTarget(label: String) {
+            when (elseConditional) {
+                "<" -> {
+                    asmgen.out("""
+                        bvc  +
+                        eor  #$80
++                       bmi  $label""")
+                }
+                ">=" -> {
+                    asmgen.out("""
+                        bvc  +
+                        eor  #$80
++                       bpl  $label""")
+                }
+                else -> throw AssemblyError("wrong conditional $elseConditional")
+            }
+        }
+        fun branchElse(label: String) {
+            when (elseConditional) {
+                "<" -> {
+                    asmgen.out("""
+                        bvc  +
+                        eor  #$80
++                       bpl  $label""")
+                }
+                ">=" -> {
+                    asmgen.out("""
+                        bvc  +
+                        eor  #$80
++                       bmi  $label""")
+                }
+                else -> throw AssemblyError("wrong conditional $elseConditional")
+            }
+        }
+
+        var target = asmgen.getJumpTarget(jump, false)
+        asmgen.cmpAwithByteValue(value, true)
+        if(target.indirect) {
+            branchElse("+")
+            if(target.needsExpressionEvaluation)
+                target = asmgen.getJumpTarget(jump)
+            asmgen.jmp(target.asmLabel, target.indirect, target.indexedX)
+            asmgen.out("+")
+        } else {
+            require(!target.needsExpressionEvaluation)
+            branchTarget(target.asmLabel)
+        }
+        asmgen.translate(elseBlock)
+    }
+
     private fun translateIfElseBodies(elseBranchInstr: String, stmt: PtIfElse) {
         // comparison value is already in A
         val afterIfLabel = asmgen.makeLabel("afterif")
@@ -154,7 +256,7 @@ internal class IfElseAsmGen(private val program: PtProgram,
             val elseLabel = asmgen.makeLabel("else")
             asmgen.out("  $elseBranchInstr  $elseLabel")
             asmgen.translate(stmt.ifScope)
-            asmgen.jmp(afterIfLabel, false)
+            asmgen.jmp(afterIfLabel)
             asmgen.out(elseLabel)
             asmgen.translate(stmt.elseScope)
         } else {
@@ -171,10 +273,9 @@ internal class IfElseAsmGen(private val program: PtProgram,
         if(target.indirect) {
             asmgen.out("  $falseBranch  +")
             if(target.needsExpressionEvaluation)
-                target = asmgen.getJumpTarget(jump, true)
-            asmgen.out("""
-                jmp  (${target.asmLabel})
-+""")
+                target = asmgen.getJumpTarget(jump)
+            asmgen.jmp(target.asmLabel, target.indirect, target.indexedX)
+            asmgen.out("+")
         } else {
             require(!target.needsExpressionEvaluation)
             asmgen.out("  $branchInstr  ${target.asmLabel}")
@@ -210,38 +311,9 @@ internal class IfElseAsmGen(private val program: PtProgram,
                     translateIfElseBodies("beq", stmt)
             }
             "<" -> translateByteLess(stmt, signed, jumpAfterIf)
-            "<=" -> {
-                // X<=Y -> Y>=X (reverse of >=)
-                asmgen.assignExpressionToRegister(condition.right, RegisterOrPair.A, signed)
-                asmgen.cmpAwithByteValue(condition.left, false)
-                return if(signed) {
-                    if(jumpAfterIf!=null)
-                        translateJumpElseBodies("bpl", "bmi", jumpAfterIf, stmt.elseScope)
-                    else
-                        translateIfElseBodies("bmi", stmt)
-                } else {
-                    if(jumpAfterIf!=null)
-                        translateJumpElseBodies("bcs", "bcc", jumpAfterIf, stmt.elseScope)
-                    else
-                        translateIfElseBodies("bcc", stmt)
-                }
-            }
+            "<=" -> translateByteLessEqual(stmt, signed, jumpAfterIf)
             ">" -> translateByteGreater(stmt, signed, jumpAfterIf)
-            ">=" -> {
-                asmgen.assignExpressionToRegister(condition.left, RegisterOrPair.A, signed)
-                asmgen.cmpAwithByteValue(condition.right, false)
-                return if(signed) {
-                    if(jumpAfterIf!=null)
-                        translateJumpElseBodies("bpl", "bmi", jumpAfterIf, stmt.elseScope)
-                    else
-                        translateIfElseBodies("bmi", stmt)
-                } else {
-                    if(jumpAfterIf!=null)
-                        translateJumpElseBodies("bcs", "bcc", jumpAfterIf, stmt.elseScope)
-                    else
-                        translateIfElseBodies("bcc", stmt)
-                }
-            }
+            ">=" -> translateByteGreaterEqual(stmt, signed, jumpAfterIf)
             in LogicalOperators -> {
                 val regAtarget = AsmAssignTarget(TargetStorageKind.REGISTER, asmgen, DataType.BOOL, stmt.definingISub(), condition.position, register=RegisterOrPair.A)
                 if (assignmentAsmGen.optimizedLogicalExpr(condition, regAtarget)) {
@@ -286,7 +358,8 @@ internal class IfElseAsmGen(private val program: PtProgram,
                         if(target.indirect) {
                             asmgen.out("  bmi  + |  beq +")
                             if(target.needsExpressionEvaluation)
-                                target = asmgen.getJumpTarget(jumpAfterIf, true)
+                                target = asmgen.getJumpTarget(jumpAfterIf)
+                            require(!target.indexedX)
                             asmgen.out("""
                                 jmp  (${target.asmLabel})
 +""")
@@ -306,7 +379,7 @@ internal class IfElseAsmGen(private val program: PtProgram,
                             val elseLabel = asmgen.makeLabel("else")
                             asmgen.out("  bmi  $elseLabel |  beq  $elseLabel")
                             asmgen.translate(stmt.ifScope)
-                            asmgen.jmp(afterIfLabel, false)
+                            asmgen.jmp(afterIfLabel)
                             asmgen.out(elseLabel)
                             asmgen.translate(stmt.elseScope)
                         } else {
@@ -353,7 +426,8 @@ internal class IfElseAsmGen(private val program: PtProgram,
                         if(target.indirect) {
                             asmgen.out("  bmi  + |  bne  ++")
                             if(target.needsExpressionEvaluation)
-                                target = asmgen.getJumpTarget(jumpAfterIf, true)
+                                target = asmgen.getJumpTarget(jumpAfterIf)
+                            require(!target.indexedX)
                             asmgen.out("""
 +                               jmp  (${target.asmLabel})
 +""")
@@ -375,7 +449,7 @@ internal class IfElseAsmGen(private val program: PtProgram,
                                 bpl  $elseLabel
 +""")
                             asmgen.translate(stmt.ifScope)
-                            asmgen.jmp(afterIfLabel, false)
+                            asmgen.jmp(afterIfLabel)
                             asmgen.out(elseLabel)
                             asmgen.translate(stmt.elseScope)
                         } else {
@@ -402,13 +476,13 @@ internal class IfElseAsmGen(private val program: PtProgram,
     private fun translateByteLess(stmt: PtIfElse, signed: Boolean, jumpAfterIf: PtJump?) {
         val condition = stmt.condition as PtBinaryExpression
         asmgen.assignExpressionToRegister(condition.left, RegisterOrPair.A, signed)
-        asmgen.cmpAwithByteValue(condition.right, false)
         if(signed) {
             if(jumpAfterIf!=null)
-                translateJumpElseBodies("bmi", "bpl", jumpAfterIf, stmt.elseScope)
+                translateJumpElseBodiesSignedByte("<", condition.right, jumpAfterIf, stmt.elseScope)
             else
-                translateIfElseBodies("bpl", stmt)
+                translateIfElseBodiesSignedByte("<", condition.right, stmt)
         } else {
+            asmgen.cmpAwithByteValue(condition.right, false)
             if(jumpAfterIf!=null)
                 translateJumpElseBodies("bcc", "bcs", jumpAfterIf, stmt.elseScope)
             else
@@ -416,25 +490,43 @@ internal class IfElseAsmGen(private val program: PtProgram,
         }
     }
 
+    private fun translateByteLessEqual(stmt: PtIfElse, signed: Boolean, jumpAfterIf: PtJump?) {
+        // X<=Y -> Y>=X (reverse of >=)
+        val condition = stmt.condition as PtBinaryExpression
+        asmgen.assignExpressionToRegister(condition.right, RegisterOrPair.A, signed)
+        return if(signed) {
+            if(jumpAfterIf!=null)
+                translateJumpElseBodiesSignedByte(">=", condition.left, jumpAfterIf, stmt.elseScope)
+            else
+                translateIfElseBodiesSignedByte(">=", condition.left, stmt)
+        } else {
+            asmgen.cmpAwithByteValue(condition.left, false)
+            if(jumpAfterIf!=null)
+                translateJumpElseBodies("bcs", "bcc", jumpAfterIf, stmt.elseScope)
+            else
+                translateIfElseBodies("bcc", stmt)
+        }
+    }
+
     private fun translateByteGreater(stmt: PtIfElse, signed: Boolean, jumpAfterIf: PtJump?) {
         val condition = stmt.condition as PtBinaryExpression
         if(signed) {
             // X>Y --> Y<X
             asmgen.assignExpressionToRegister(condition.right, RegisterOrPair.A, true)
-            asmgen.cmpAwithByteValue(condition.left, true)
             if (jumpAfterIf != null)
-                translateJumpElseBodies("bmi", "bpl", jumpAfterIf, stmt.elseScope)
+                translateJumpElseBodiesSignedByte("<", condition.left, jumpAfterIf, stmt.elseScope)
             else
-                translateIfElseBodies("bpl", stmt)
+                translateIfElseBodiesSignedByte("<", condition.left, stmt)
         } else {
-            asmgen.assignExpressionToRegister(condition.left, RegisterOrPair.A, false)
+            asmgen.assignExpressionToRegister(condition.left, RegisterOrPair.A)
             asmgen.cmpAwithByteValue(condition.right, false)
             if(jumpAfterIf!=null) {
                 var target = asmgen.getJumpTarget(jumpAfterIf, false)
                 if(target.indirect) {
                     asmgen.out("  bcc  + |  beq  +")
                     if(target.needsExpressionEvaluation)
-                        target = asmgen.getJumpTarget(jumpAfterIf, true)
+                        target = asmgen.getJumpTarget(jumpAfterIf)
+                    require(!target.indexedX)
                     asmgen.out("""
                         jmp  (${target.asmLabel})
 +""")
@@ -453,7 +545,7 @@ internal class IfElseAsmGen(private val program: PtProgram,
                     val elseLabel = asmgen.makeLabel("else")
                     asmgen.out("  bcc  $elseLabel |  beq  $elseLabel")
                     asmgen.translate(stmt.ifScope)
-                    asmgen.jmp(afterIfLabel, false)
+                    asmgen.jmp(afterIfLabel)
                     asmgen.out(elseLabel)
                     asmgen.translate(stmt.elseScope)
                 } else {
@@ -466,6 +558,23 @@ internal class IfElseAsmGen(private val program: PtProgram,
         }
     }
 
+    private fun translateByteGreaterEqual(stmt: PtIfElse, signed: Boolean, jumpAfterIf: PtJump?) {
+        val condition = stmt.condition as PtBinaryExpression
+        asmgen.assignExpressionToRegister(condition.left, RegisterOrPair.A, signed)
+        return if(signed) {
+            if(jumpAfterIf!=null)
+                translateJumpElseBodiesSignedByte(">=", condition.right, jumpAfterIf, stmt.elseScope)
+            else
+                translateIfElseBodiesSignedByte(">=", condition.right, stmt)
+        } else {
+            asmgen.cmpAwithByteValue(condition.right, false)
+            if(jumpAfterIf!=null)
+                translateJumpElseBodies("bcs", "bcc", jumpAfterIf, stmt.elseScope)
+            else
+                translateIfElseBodies("bcc", stmt)
+        }
+    }
+
     private fun translateIfWord(stmt: PtIfElse, condition: PtBinaryExpression, jumpAfterIf: PtJump?) {
         val signed = condition.left.type.isSigned
         val constValue = condition.right.asConstInteger()
@@ -535,7 +644,8 @@ internal class IfElseAsmGen(private val program: PtProgram,
                             eor  #128
 +                           bpl  +""")
                         if(target.needsExpressionEvaluation)
-                            target = asmgen.getJumpTarget(jump, true)
+                            target = asmgen.getJumpTarget(jump)
+                        require(!target.indexedX)
                         asmgen.out("""
                             jmp  (${target.asmLabel})
 +""")
@@ -562,7 +672,7 @@ internal class IfElseAsmGen(private val program: PtProgram,
                             eor  #128
 +                           bmi  $elseLabel""")
                         asmgen.translate(stmt.ifScope)
-                        asmgen.jmp(afterIfLabel, false)
+                        asmgen.jmp(afterIfLabel)
                         asmgen.out(elseLabel)
                         asmgen.translate(stmt.elseScope)
                     } else {
@@ -590,7 +700,8 @@ internal class IfElseAsmGen(private val program: PtProgram,
                             cmp  $valueLsb
                             bcs  +""")
                         if(target.needsExpressionEvaluation)
-                            target = asmgen.getJumpTarget(jump, true)
+                            target = asmgen.getJumpTarget(jump)
+                        require(!target.indexedX)
                         asmgen.out("""
 _jump                       jmp  (${target.asmLabel})
 +""")
@@ -615,7 +726,7 @@ _jump                       jmp  (${target.asmLabel})
                             sbc  $valueMsb
                             bcs  $elseLabel""")
                         asmgen.translate(stmt.ifScope)
-                        asmgen.jmp(afterIfLabel, false)
+                        asmgen.jmp(afterIfLabel)
                         asmgen.out(elseLabel)
                         asmgen.translate(stmt.elseScope)
                     } else {
@@ -667,7 +778,8 @@ _jump                       jmp  (${target.asmLabel})
                             eor  #128
 +                           bpl  +""")
                         if(target.needsExpressionEvaluation)
-                            target = asmgen.getJumpTarget(jump, true)
+                            target = asmgen.getJumpTarget(jump)
+                        require(!target.indexedX)
                         asmgen.out("""
                            jmp  (${target.asmLabel})
 +""")
@@ -694,7 +806,7 @@ _jump                       jmp  (${target.asmLabel})
                             eor  #128
 +                           bmi  $elseLabel""")
                         asmgen.translate(stmt.ifScope)
-                        asmgen.jmp(afterIfLabel, false)
+                        asmgen.jmp(afterIfLabel)
                         asmgen.out(elseLabel)
                         asmgen.translate(stmt.elseScope)
                     } else {
@@ -721,7 +833,8 @@ _jump                       jmp  (${target.asmLabel})
                             sbc  $valueMsb
                             bcc  +""")
                         if(target.needsExpressionEvaluation)
-                            target = asmgen.getJumpTarget(jump, true)
+                            target = asmgen.getJumpTarget(jump)
+                        require(!target.indexedX)
                         asmgen.out("""
                             jmp  (${target.asmLabel})
 +""")
@@ -744,7 +857,7 @@ _jump                       jmp  (${target.asmLabel})
                             sbc  $valueMsb
                             bcc  $elseLabel""")
                         asmgen.translate(stmt.ifScope)
-                        asmgen.jmp(afterIfLabel, false)
+                        asmgen.jmp(afterIfLabel)
                         asmgen.out(elseLabel)
                         asmgen.translate(stmt.elseScope)
                     } else {
@@ -784,7 +897,9 @@ _jump                       jmp  (${target.asmLabel})
     private fun loadAndCmp0MSB(value: PtExpression) {
         when(value) {
             is PtArrayIndexer -> {
-                val varname = asmgen.asmVariableName(value.variable)
+                if(value.variable==null)
+                    TODO("support for ptr indexing ${value.position}")
+                val varname = asmgen.asmVariableName(value.variable!!)
                 asmgen.loadScaledArrayIndexIntoRegister(value, CpuRegister.Y)
                 if(value.splitWords)
                     asmgen.out("  lda  ${varname}_msb,y")
@@ -800,8 +915,8 @@ _jump                       jmp  (${target.asmLabel})
                     asmgen.assignExpressionToRegister(value, RegisterOrPair.AY, true)
                     asmgen.out("  cpy  #0")
                 } else {
-                    var varname = asmgen.asmVariableName(value.identifier)
-                    if(value.identifier.type.isSplitWordArray) {
+                    var varname = asmgen.asmVariableName(value.identifier!!)
+                    if(value.identifier!!.type.isSplitWordArray) {
                         varname += if(value.isMsbForSplitArray) "_msb" else "_lsb"
                     }
                     asmgen.out("  lda  #>$varname")
@@ -829,7 +944,8 @@ _jump                       jmp  (${target.asmLabel})
                             lda  $valueLsb
                             bne  ++""")
                         if(target.needsExpressionEvaluation)
-                            target = asmgen.getJumpTarget(jump, true)
+                            target = asmgen.getJumpTarget(jump)
+                        require(!target.indexedX)
                         asmgen.out("""
 +                           jmp  (${target.asmLabel})
 +""")
@@ -857,7 +973,7 @@ _jump                       jmp  (${target.asmLabel})
                             bne  $elseLabel
 +""")
                         asmgen.translate(stmt.ifScope)
-                        asmgen.jmp(afterIfLabel, false)
+                        asmgen.jmp(afterIfLabel)
                         asmgen.out(elseLabel)
                         asmgen.translate(stmt.elseScope)
                     } else {
@@ -878,8 +994,10 @@ _jump                       jmp  (${target.asmLabel})
             if(value is PtIdentifier)
                 return compareLsbMsb(value.name, value.name+"+1")
             if(value is PtArrayIndexer) {
+                if(value.variable==null)
+                    TODO("support for ptr indexing ${value.position}")
                 val constIndex = value.index.asConstInteger()
-                val varname = asmgen.asmVariableName(value.variable)
+                val varname = asmgen.asmVariableName(value.variable!!)
                 if(constIndex!=null) {
                     if(value.splitWords) {
                         return compareLsbMsb("${varname}_lsb+$constIndex", "${varname}_msb+$constIndex")
@@ -908,7 +1026,8 @@ _jump                       jmp  (${target.asmLabel})
                         cmp  #0
                         bne  ++""")
                     if(target.needsExpressionEvaluation)
-                        target = asmgen.getJumpTarget(jump, true)
+                        target = asmgen.getJumpTarget(jump)
+                    require(!target.indexedX)
                     asmgen.out("""
 +                       jmp  (${target.asmLabel})
 +""")
@@ -936,7 +1055,7 @@ _jump                       jmp  (${target.asmLabel})
                             bne  $elseLabel
 +""")
                     asmgen.translate(stmt.ifScope)
-                    asmgen.jmp(afterIfLabel, false)
+                    asmgen.jmp(afterIfLabel)
                     asmgen.out(elseLabel)
                     asmgen.translate(stmt.elseScope)
                 } else {
@@ -973,7 +1092,8 @@ _jump                       jmp  (${target.asmLabel})
                             lda  $valueLsb
                             beq  ++""")
                         if(target.needsExpressionEvaluation)
-                            target = asmgen.getJumpTarget(jump, true)
+                            target = asmgen.getJumpTarget(jump)
+                        require(!target.indexedX)
                         asmgen.out("""
 +                           jmp  (${target.asmLabel})
 +""")
@@ -1001,7 +1121,7 @@ _jump                       jmp  (${target.asmLabel})
                             beq  $elseLabel
 +""")
                         asmgen.translate(stmt.ifScope)
-                        asmgen.jmp(afterIfLabel, false)
+                        asmgen.jmp(afterIfLabel)
                         asmgen.out(elseLabel)
                         asmgen.translate(stmt.elseScope)
                     } else {
@@ -1023,8 +1143,10 @@ _jump                       jmp  (${target.asmLabel})
             if(value is PtIdentifier)
                 return compareLsbMsb(value.name, value.name+"+1")
             if(value is PtArrayIndexer) {
+                if(value.variable==null)
+                    TODO("support for ptr indexing ${value.position}")
                 val constIndex = value.index.asConstInteger()
-                val varname = asmgen.asmVariableName(value.variable)
+                val varname = asmgen.asmVariableName(value.variable!!)
                 if(constIndex!=null) {
                     if(value.splitWords) {
                         return compareLsbMsb("${varname}_lsb+$constIndex", "${varname}_msb+$constIndex")
@@ -1053,7 +1175,8 @@ _jump                       jmp  (${target.asmLabel})
                         cmp  #0
                         beq  ++""")
                     if(target.needsExpressionEvaluation)
-                        target = asmgen.getJumpTarget(jump, true)
+                        target = asmgen.getJumpTarget(jump)
+                    require(!target.indexedX)
                     asmgen.out("""
 +                       jmp  (${target.asmLabel})
 +""")
@@ -1081,7 +1204,7 @@ _jump                       jmp  (${target.asmLabel})
                             beq  $elseLabel
 +""")
                     asmgen.translate(stmt.ifScope)
-                    asmgen.jmp(afterIfLabel, false)
+                    asmgen.jmp(afterIfLabel)
                     asmgen.out(elseLabel)
                     asmgen.translate(stmt.elseScope)
                 } else {
@@ -1136,7 +1259,9 @@ _jump                       jmp  (${target.asmLabel})
                 is PtArrayIndexer -> {
                     val constIndex = value.index.asConstInteger()
                     if(constIndex!=null) {
-                        val varName = asmgen.asmVariableName(value.variable)
+                        if(value.variable==null)
+                            TODO("support for ptr indexing ${value.position}")
+                        val varName = asmgen.asmVariableName(value.variable!!)
                         if(value.splitWords) {
                             return translateLoadFromVarSplitw(varName, constIndex, "bne", "beq")
                         }
@@ -1157,7 +1282,9 @@ _jump                       jmp  (${target.asmLabel})
                 is PtArrayIndexer -> {
                     val constIndex = value.index.asConstInteger()
                     if (constIndex != null) {
-                        val varName = asmgen.asmVariableName(value.variable)
+                        if(value.variable==null)
+                            TODO("support for ptr indexing ${value.position}")
+                        val varName = asmgen.asmVariableName(value.variable!!)
                         if(value.splitWords) {
                             return translateLoadFromVarSplitw(varName, constIndex, "beq", "bne")
                         }
@@ -1196,7 +1323,8 @@ _jump                       jmp  (${target.asmLabel})
                         cpy  $valueMsb
                         beq  ++""")
                     if(target.needsExpressionEvaluation)
-                        target = asmgen.getJumpTarget(jump, true)
+                        target = asmgen.getJumpTarget(jump)
+                    require(!target.indexedX)
                     asmgen.out("""
 +                       jmp  (${target.asmLabel})
 +""")
@@ -1221,7 +1349,7 @@ _jump                       jmp  (${target.asmLabel})
                         beq  $elseLabel
 +""")
                     asmgen.translate(stmt.ifScope)
-                    asmgen.jmp(afterIfLabel, false)
+                    asmgen.jmp(afterIfLabel)
                     asmgen.out(elseLabel)
                     asmgen.translate(stmt.elseScope)
                 } else {
@@ -1248,7 +1376,8 @@ _jump                       jmp  (${target.asmLabel})
                         cpy  $valueMsb
                         bne  +""")
                     if(target.needsExpressionEvaluation)
-                        target = asmgen.getJumpTarget(jump, true)
+                        target = asmgen.getJumpTarget(jump)
+                    require(!target.indexedX)
                     asmgen.out("""
                         jmp  (${target.asmLabel})
 +""")
@@ -1273,7 +1402,7 @@ _jump                       jmp  (${target.asmLabel})
                         cpy  $valueMsb
                         bne  $elseLabel""")
                     asmgen.translate(stmt.ifScope)
-                    asmgen.jmp(afterIfLabel, false)
+                    asmgen.jmp(afterIfLabel)
                     asmgen.out(elseLabel)
                     asmgen.translate(stmt.elseScope)
                 } else {
@@ -1302,7 +1431,8 @@ _jump                       jmp  (${target.asmLabel})
                             cmp  ${right.name}+1
                             beq  ++""")
                         if(target.needsExpressionEvaluation)
-                            target = asmgen.getJumpTarget(jump, true)
+                            target = asmgen.getJumpTarget(jump)
+                        require(!target.indexedX)
                         asmgen.out("""
 +                           jmp  (${target.asmLabel})
 +""")
@@ -1331,7 +1461,7 @@ _jump                       jmp  (${target.asmLabel})
                             beq  $elseLabel
 +""")
                         asmgen.translate(stmt.ifScope)
-                        asmgen.jmp(afterIfLabel, false)
+                        asmgen.jmp(afterIfLabel)
                         asmgen.out(elseLabel)
                         asmgen.translate(stmt.elseScope)
                     } else {
@@ -1361,7 +1491,8 @@ _jump                       jmp  (${target.asmLabel})
                             cmp  ${right.name}+1
                             bne  +""")
                         if(target.needsExpressionEvaluation)
-                            target = asmgen.getJumpTarget(jump, true)
+                            target = asmgen.getJumpTarget(jump)
+                        require(!target.indexedX)
                         asmgen.out("""
                             jmp  (${target.asmLabel})
 +""")
@@ -1390,7 +1521,7 @@ _jump                       jmp  (${target.asmLabel})
                             cmp  ${right.name}+1
                             bne  $elseLabel""")
                         asmgen.translate(stmt.ifScope)
-                        asmgen.jmp(afterIfLabel, false)
+                        asmgen.jmp(afterIfLabel)
                         asmgen.out(elseLabel)
                         asmgen.translate(stmt.elseScope)
                     } else {
@@ -1423,7 +1554,8 @@ _jump                       jmp  (${target.asmLabel})
                             cmp  #>$value
                             beq  ++""")
                         if(target.needsExpressionEvaluation)
-                            target = asmgen.getJumpTarget(jump, true)
+                            target = asmgen.getJumpTarget(jump)
+                        require(!target.indexedX)
                         asmgen.out("""
 +                           jmp  (${target.asmLabel})
 +""")
@@ -1452,7 +1584,7 @@ _jump                       jmp  (${target.asmLabel})
                             beq  $elseLabel
 +""")
                         asmgen.translate(stmt.ifScope)
-                        asmgen.jmp(afterIfLabel, false)
+                        asmgen.jmp(afterIfLabel)
                         asmgen.out(elseLabel)
                         asmgen.translate(stmt.elseScope)
                     } else {
@@ -1481,7 +1613,8 @@ _jump                       jmp  (${target.asmLabel})
                             cmp  #>$value
                             bne  +""")
                         if(target.needsExpressionEvaluation)
-                            target = asmgen.getJumpTarget(jump, true)
+                            target = asmgen.getJumpTarget(jump)
+                        require(!target.indexedX)
                         asmgen.out("""
                             jmp  (${target.asmLabel})
 +""")
@@ -1510,7 +1643,7 @@ _jump                       jmp  (${target.asmLabel})
                             cmp  #>$value
                             bne  $elseLabel""")
                         asmgen.translate(stmt.ifScope)
-                        asmgen.jmp(afterIfLabel, false)
+                        asmgen.jmp(afterIfLabel)
                         asmgen.out(elseLabel)
                         asmgen.translate(stmt.elseScope)
                     } else {
@@ -1532,8 +1665,10 @@ _jump                       jmp  (${target.asmLabel})
         fun translateEqualsArray(left: PtArrayIndexer, right: PtExpression) {
             val constIndex = left.index.asConstInteger()
             if(constIndex!=null) {
+                if(left.variable==null)
+                    TODO("support for ptr indexing ${left.position}")
                 asmgen.assignExpressionToRegister(right, RegisterOrPair.AY, signed)
-                val varName = asmgen.asmVariableName(left.variable)
+                val varName = asmgen.asmVariableName(left.variable!!)
                 if(left.splitWords) {
                     return if(notEquals)
                         translateAYNotEquals("${varName}_lsb+$constIndex", "${varName}_msb+$constIndex")
@@ -1596,13 +1731,13 @@ _jump                       jmp  (${target.asmLabel})
                     }
                 }
                 is PtAddressOf -> {
-                    if(left.isFromArrayElement)
+                    if(left.isFromArrayElement) {
                         fallbackTranslateForSimpleCondition(stmt)
-                    else {
-                        val varname = if(left.identifier.type.isSplitWordArray) {
-                            if(left.isMsbForSplitArray) left.identifier.name+"_msb" else left.identifier.name+"_lsb"
+                    } else {
+                        val varname = if(left.identifier!!.type.isSplitWordArray) {
+                            if(left.isMsbForSplitArray) left.identifier!!.name+"_msb" else left.identifier!!.name+"_lsb"
                         } else {
-                            left.identifier.name
+                            left.identifier!!.name
                         }
                         asmgen.assignExpressionToRegister(right, RegisterOrPair.AY, signed)
                         translateAYNotEquals("#<$varname", "#>$varname")
@@ -1648,13 +1783,13 @@ _jump                       jmp  (${target.asmLabel})
                     }
                 }
                 is PtAddressOf -> {
-                    if(left.isFromArrayElement)
+                    if(left.isFromArrayElement) {
                         fallbackTranslateForSimpleCondition(stmt)
-                    else {
-                        val varname = if(left.identifier.type.isSplitWordArray) {
-                            if(left.isMsbForSplitArray) left.identifier.name+"_msb" else left.identifier.name+"_lsb"
+                    } else {
+                        val varname = if(left.identifier!!.type.isSplitWordArray) {
+                            if(left.isMsbForSplitArray) left.identifier!!.name+"_msb" else left.identifier!!.name+"_lsb"
                         } else {
-                            left.identifier.name
+                            left.identifier!!.name
                         }
                         asmgen.assignExpressionToRegister(right, RegisterOrPair.AY, signed)
                         translateAYEquals("#<$varname", "#>$varname")

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

@@ -15,18 +15,18 @@ internal class IfExpressionAsmGen(private val asmgen: AsmGen6502Internal, privat
         evalIfExpressionConditonAndBranchWhenFalse(expr.condition, falseLabel)
         when {
             expr.type.isByteOrBool -> {
-                asmgen.assignExpressionToRegister(expr.truevalue, RegisterOrPair.A, false)
+                asmgen.assignExpressionToRegister(expr.truevalue, RegisterOrPair.A)
                 asmgen.jmp(endLabel)
                 asmgen.out(falseLabel)
-                asmgen.assignExpressionToRegister(expr.falsevalue, RegisterOrPair.A, false)
+                asmgen.assignExpressionToRegister(expr.falsevalue, RegisterOrPair.A)
                 asmgen.out(endLabel)
                 assignmentAsmGen.assignRegisterByte(target, CpuRegister.A, false, false)
             }
             expr.type.isWord || expr.type.isString -> {
-                asmgen.assignExpressionToRegister(expr.truevalue, RegisterOrPair.AY, false)
+                asmgen.assignExpressionToRegister(expr.truevalue, RegisterOrPair.AY)
                 asmgen.jmp(endLabel)
                 asmgen.out(falseLabel)
-                asmgen.assignExpressionToRegister(expr.falsevalue, RegisterOrPair.AY, false)
+                asmgen.assignExpressionToRegister(expr.falsevalue, RegisterOrPair.AY)
                 asmgen.out(endLabel)
                 assignmentAsmGen.assignRegisterpairWord(target, RegisterOrPair.AY)
             }
@@ -195,7 +195,7 @@ internal class IfExpressionAsmGen(private val asmgen: AsmGen6502Internal, privat
                 beq  $falseLabel
 +""")
         } else {
-            asmgen.assignExpressionToRegister(expr, RegisterOrPair.AY, false)
+            asmgen.assignExpressionToRegister(expr, RegisterOrPair.AY)
             asmgen.out("""
                 cmp  $varRight
                 bne  +
@@ -219,7 +219,7 @@ internal class IfExpressionAsmGen(private val asmgen: AsmGen6502Internal, privat
                 cmp  $varRight+1
                 bne  $falseLabel""")
         } else {
-            asmgen.assignExpressionToRegister(expr, RegisterOrPair.AY, false)
+            asmgen.assignExpressionToRegister(expr, RegisterOrPair.AY)
             asmgen.out("""
                 cmp  $varRight
                 bne  $falseLabel
@@ -242,7 +242,7 @@ internal class IfExpressionAsmGen(private val asmgen: AsmGen6502Internal, privat
                 beq  $falseLabel
 +""")
         } else {
-            asmgen.assignExpressionToRegister(expr, RegisterOrPair.AY, false)
+            asmgen.assignExpressionToRegister(expr, RegisterOrPair.AY)
             asmgen.out("""
                 cmp  #<$number
                 bne  +
@@ -265,7 +265,7 @@ internal class IfExpressionAsmGen(private val asmgen: AsmGen6502Internal, privat
                 cmp  #>$number
                 bne  $falseLabel""")
         } else {
-            asmgen.assignExpressionToRegister(expr, RegisterOrPair.AY, false)
+            asmgen.assignExpressionToRegister(expr, RegisterOrPair.AY)
             asmgen.out(                """
                 cmp  #<$number
                 bne  $falseLabel
@@ -284,7 +284,7 @@ internal class IfExpressionAsmGen(private val asmgen: AsmGen6502Internal, privat
                 ora  $varname+1
                 beq  $falseLabel""")
         } else {
-            asmgen.assignExpressionToRegister(expr, RegisterOrPair.AY, false)
+            asmgen.assignExpressionToRegister(expr, RegisterOrPair.AY)
             asmgen.out("  sty  P8ZP_SCRATCH_REG |  ora  P8ZP_SCRATCH_REG |  beq  $falseLabel")
         }
     }
@@ -299,7 +299,7 @@ internal class IfExpressionAsmGen(private val asmgen: AsmGen6502Internal, privat
                 ora  $varname+1
                 bne  $falseLabel""")
         } else {
-            asmgen.assignExpressionToRegister(expr, RegisterOrPair.AY, false)
+            asmgen.assignExpressionToRegister(expr, RegisterOrPair.AY)
             asmgen.out("  sty  P8ZP_SCRATCH_REG |  ora  P8ZP_SCRATCH_REG |  bne  $falseLabel")
         }
     }

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

@@ -44,8 +44,8 @@ internal class ProgramAndVarsGen(
                 asmgen.out("${flt.value}\t.byte  $floatFill  ; float $floatvalue")
             }
 
+            structInstances2asm()
             memorySlabs()
-            tempVars()
             footer()
         }
     }
@@ -208,40 +208,20 @@ internal class ProgramAndVarsGen(
 
     private fun memorySlabs() {
         if(symboltable.allMemorySlabs.isNotEmpty()) {
-            asmgen.out("; memory slabs\n  .section slabs_BSS")
+            asmgen.out("; memory slabs\n  .section BSS_SLABS")
             asmgen.out("prog8_slabs\t.block")
             for (slab in symboltable.allMemorySlabs) {
                 if (slab.align > 1u)
                     asmgen.out("\t.align  ${slab.align.toHex()}")
                 asmgen.out("${slab.name}\t.fill  ${slab.size}")
             }
-            asmgen.out("\t.bend\n  .send slabs_BSS")
+            asmgen.out("\t.bend\n  .send BSS_SLABS")
         }
     }
 
-    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) {
-                        BaseDataType.BOOL  -> asmgen.out("$name    .byte  ?")
-                        BaseDataType.BYTE  -> asmgen.out("$name    .char  ?")
-                        BaseDataType.UBYTE -> asmgen.out("$name    .byte  ?")
-                        BaseDataType.WORD  -> asmgen.out("$name    .sint  ?")
-                        BaseDataType.UWORD -> asmgen.out("$name    .word  ?")
-                        BaseDataType.FLOAT -> asmgen.out("$name    .fill  ${options.compTarget.FLOAT_MEM_SIZE}")
-                        BaseDataType.LONG -> throw AssemblyError("should not have a variable with long dt only constants")
-                        else -> throw AssemblyError("weird dt for extravar $dt")
-                    }
-                }
-            }
-        }
-        asmgen.out("  .send BSS")
-    }
-
     private fun footer() {
+        asmgen.out("  .dsection STRUCTINSTANCES\n")
+
         var relocateBssVars = false
         var relocateBssSlabs = false
         var relocatedBssStart = 0u
@@ -297,14 +277,14 @@ internal class ProgramAndVarsGen(
         asmgen.out("PROG8_VARSHIGH_RAMBANK = ${options.varsHighBank ?: 1}")
         if(relocateBssVars) {
             if(!relocateBssSlabs)
-                asmgen.out("  .dsection slabs_BSS")
+                asmgen.out("  .dsection BSS_SLABS")
             asmgen.out("prog8_program_end\t; end of program label for progend()")
             asmgen.out("  * = ${relocatedBssStart.toHex()}")
             asmgen.out("  .dsection BSS_NOCLEAR")
             asmgen.out("prog8_bss_section_start")
             asmgen.out("  .dsection BSS")
             if(relocateBssSlabs)
-                asmgen.out("  .dsection slabs_BSS")
+                asmgen.out("  .dsection BSS_SLABS")
             asmgen.out("  .cerror * > ${relocatedBssEnd.toHex()}, \"too many variables/data for BSS section\"")
             asmgen.out("prog8_bss_section_size = * - prog8_bss_section_start")
         } else {
@@ -313,12 +293,12 @@ internal class ProgramAndVarsGen(
             asmgen.out("  .dsection BSS")
             asmgen.out("prog8_bss_section_size = * - prog8_bss_section_start")
             if(!relocateBssSlabs)
-                asmgen.out("  .dsection slabs_BSS")
+                asmgen.out("  .dsection BSS_SLABS")
             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\"")
+                asmgen.out("  .dsection BSS_SLABS")
+                asmgen.out("  .cerror * > ${relocatedBssEnd.toHex()}, \"too many data for BSS_SLABS section\"")
             }
         }
 
@@ -351,9 +331,10 @@ internal class ProgramAndVarsGen(
         if (initializers.isNotEmpty()) {
             asmgen.out("prog8_init_vars\t.block")
             initializers.forEach { assign ->
-                if((assign.value as? PtNumber)?.number != 0.0 || allocator.isZpVar(assign.target.identifier!!.name))
+                val constvalue = assign.value as? PtNumber
+                if(constvalue==null || constvalue.number!=0.0 || allocator.isZpVar(assign.target.identifier!!.name))
                     asmgen.translate(assign)
-                // the other variables that should be set to zero are done so as part of the BSS section.
+                // the other variables that should be set to zero are done so as part of the BSS section clear.
             }
             asmgen.out("  rts\n  .bend")
         }
@@ -370,7 +351,7 @@ internal class ProgramAndVarsGen(
         val varsInBlock = getVars(scope)
 
         // Zeropage Variables
-        val varnames = varsInBlock.filter { it.value.type==StNodeType.STATICVAR }.map { it.value.scopedName }.toSet()
+        val varnames = varsInBlock.filter { it.value.type==StNodeType.STATICVAR }.map { it.value.scopedNameString }.toSet()
         zeropagevars2asm(varnames)
 
         // MemDefs and Consts
@@ -384,11 +365,93 @@ internal class ProgramAndVarsGen(
 
         // normal statically allocated variables
         val variables = varsInBlock
-            .filter { it.value.type==StNodeType.STATICVAR && !allocator.isZpVar(it.value.scopedName) }
+            .filter { it.value.type==StNodeType.STATICVAR && !allocator.isZpVar(it.value.scopedNameString) }
             .map { it.value as StStaticVariable }
         nonZpVariables2asm(variables)
     }
 
+    private fun asmTypeString(dt: DataType): String {
+        return when {
+            dt.isBool || dt.isUnsignedByte -> ".byte"
+            dt.isSignedByte -> ".char"
+            dt.isUnsignedWord || dt.isPointer -> ".word"
+            dt.isSignedWord -> ".sint"
+            dt.isFloat -> ".byte"
+            else -> {
+                throw AssemblyError("weird dt")
+            }
+        }
+    }
+
+    private fun structInstances2asm() {
+
+        fun initValues(instance: StStructInstance): List<String> {
+            val structtype: StStruct = symboltable.lookup(instance.structName) as StStruct
+            return structtype.fields.zip(instance.initialValues).map { (field, value) ->
+                if(field.first.isFloat) {
+                    "["+compTarget.getFloatAsmBytes(value.number!!)+"]"
+                } else {
+                    when {
+                        value.number!=null -> {
+                            if(field.first.isPointer)
+                                "$"+value.number!!.toInt().toString(16)
+                            else if(field.first.isInteger)
+                                value.number!!.toInt().toString()
+                            else
+                                value.number.toString()
+                        }
+                        value.addressOfSymbol!=null -> value.addressOfSymbol!!
+                        value.boolean!=null -> if(value.boolean==true) "1" else "0"
+                        else -> throw AssemblyError("weird struct initial value $value")
+                    }
+                }
+            }
+        }
+
+
+        asmgen.out("; struct types")
+        symboltable.allStructInstances.distinctBy { it.structName }.forEach {
+            val structtype: StStruct = symboltable.lookup(it.structName) as StStruct
+            val structargs = structtype.fields.withIndex().joinToString(",") { field -> "f${field.index}" }
+            asmgen.out("${it.structName}    .struct $structargs\n")
+            structtype.fields.withIndex().forEach { (index, field) ->
+                val dt = field.first
+                val varname = "f${index}"
+                val type = when {
+                    dt.isBool || dt.isUnsignedByte -> ".byte"
+                    dt.isSignedByte -> ".char"
+                    dt.isUnsignedWord || dt.isPointer -> ".word"
+                    dt.isSignedWord -> ".sint"
+                    dt.isFloat -> ".byte"   // TODO check that float bytes are passed as an array parameter
+                    else -> throw AssemblyError("weird dt")
+                }
+                asmgen.out("p8v_${field.second}  $type  \\$varname")        // note: struct field symbol prefixing done here because that is a lot simpler than fixing up all expressions in the AST
+            }
+            asmgen.out("    .endstruct\n")
+        }
+
+        val (instancesNoInit, instances) = symboltable.allStructInstances.partition { it.initialValues.isEmpty() }
+        asmgen.out("; struct instances without initialization values, as BSS zeroed at startup\n")
+        asmgen.out("    .section BSS\n")
+        instancesNoInit.forEach {
+            val structtype: StStruct = symboltable.lookup(it.structName) as StStruct
+            val zerovalues = structtype.fields.map { field ->
+                if(field.first.isFloat) {
+                    val floatbytes = List(compTarget.memorySize(BaseDataType.FLOAT)) { "?" }
+                    "[${floatbytes.joinToString(",")}]"
+                }
+                else "?"
+            }
+            asmgen.out("${it.name}    .dstruct  ${it.structName}, ${zerovalues.joinToString(",")}\n")
+        }
+        asmgen.out("    .send BSS\n")
+
+        asmgen.out("; struct instances with initialization values\n")
+        asmgen.out("    .section STRUCTINSTANCES\n")
+        instances.forEach { asmgen.out("${it.name}    .dstruct  ${it.structName}, ${initValues(it).joinToString(",")}\n") }
+        asmgen.out("    .send STRUCTINSTANCES\n")
+    }
+
     internal fun translateAsmSubroutine(sub: PtAsmSub) {
         if(sub.inline) {
             return      // subroutine gets inlined at call site.
@@ -438,7 +501,7 @@ internal class ProgramAndVarsGen(
         val varsInSubroutine = getVars(scope)
 
         // Zeropage Variables
-        val varnames = varsInSubroutine.filter { it.value.type==StNodeType.STATICVAR }.map { it.value.scopedName }.toSet()
+        val varnames = varsInSubroutine.filter { it.value.type==StNodeType.STATICVAR }.map { it.value.scopedNameString }.toSet()
         zeropagevars2asm(varnames)
 
         // MemDefs and Consts
@@ -456,7 +519,7 @@ internal class ProgramAndVarsGen(
         if((sub.name=="start" || sub.name=="p8s_start") && (sub.definingBlock()!!.name=="main" || sub.definingBlock()!!.name=="p8b_main"))
             entrypointInitialization()
 
-        val params = sub.parameters
+        val params = sub.signature.children.filterIsInstance<PtSubroutineParameter>()
         if(functioncallAsmGen.optimizeIntArgsViaCpuRegisters(params)) {
             asmgen.out("; simple int arg(s) passed via cpu register(s)")
 
@@ -492,14 +555,14 @@ internal class ProgramAndVarsGen(
         sub.children.forEach { asmgen.translate(it) }
 
         asmgen.out("; variables")
-        asmgen.out("    .section BSS")
+        asmgen.out("    .section BSS_NOCLEAR")      // these extra vars are initialized before use
         val asmGenInfo = asmgen.subroutineExtra(sub)
         for((dt, name, addr) in asmGenInfo.extraVars) {
             if(addr!=null)
                 asmgen.out("$name = $addr")
             else when(dt) {
-                BaseDataType.UBYTE -> asmgen.out("$name    .byte  ?")
-                BaseDataType.UWORD -> asmgen.out("$name    .word  ?")
+                BaseDataType.UBYTE, BaseDataType.BYTE, BaseDataType.BOOL -> asmgen.out("$name    .byte  ?")
+                BaseDataType.UWORD, BaseDataType.WORD -> asmgen.out("$name    .word  ?")
                 BaseDataType.FLOAT -> asmgen.out("$name    .fill  ${options.compTarget.FLOAT_MEM_SIZE}")
                 else -> throw AssemblyError("weird dt for extravar $dt")
             }
@@ -508,11 +571,11 @@ internal class ProgramAndVarsGen(
             asmgen.out("$subroutineFloatEvalResultVar1    .fill  ${options.compTarget.FLOAT_MEM_SIZE}")
         if(asmGenInfo.usedFloatEvalResultVar2)
             asmgen.out("$subroutineFloatEvalResultVar2    .fill  ${options.compTarget.FLOAT_MEM_SIZE}")
-        asmgen.out("  .send BSS")
+        asmgen.out("  .send BSS_NOCLEAR")
 
         // normal statically allocated variables
         val variables = varsInSubroutine
-            .filter { it.value.type==StNodeType.STATICVAR && !allocator.isZpVar(it.value.scopedName) }
+            .filter { it.value.type==StNodeType.STATICVAR && !allocator.isZpVar(it.value.scopedNameString) }
             .map { it.value as StStaticVariable }
         nonZpVariables2asm(variables)
 
@@ -567,12 +630,12 @@ internal class ProgramAndVarsGen(
 
         stringVarsWithInitInZp.forEach {
             val varname = asmgen.asmVariableName(it.name)+"_init_value"
-            outputStringvar(varname, 0, it.value.second, it.value.first)
+            outputStringvar(varname, 0u, it.value.second, it.value.first)
         }
 
         arrayVarsWithInitInZp.forEach {
             val varname = asmgen.asmVariableName(it.name)+"_init_value"
-            arrayVariable2asm(varname, it.alloc.dt, 0, it.value, null)
+            arrayVariable2asm(varname, it.alloc.dt, 0u, it.value, null)
         }
 
         asmgen.out("+")
@@ -636,22 +699,37 @@ internal class ProgramAndVarsGen(
         val (varsNoInit, varsWithInit) = variables.partition { it.uninitialized }
         if(varsNoInit.isNotEmpty()) {
             asmgen.out("; non-zeropage variables")
-            asmgen.out("  .section BSS")
-            val (notAligned, aligned) = varsNoInit.partition { it.align==0 }
-            notAligned.sortedWith(compareBy<StStaticVariable> { it.name }.thenBy { it.dt.base }).forEach {
-                uninitializedVariable2asm(it)
+            val (dirty, clean) = varsNoInit.partition { it.dirty }
+
+            fun generate(section: String, variables: List<StStaticVariable>) {
+                asmgen.out("  .section $section")
+                val (notAligned, aligned) = variables.partition { it.align == 0u }
+                notAligned.sortedWith(compareBy<StStaticVariable> { it.name }.thenBy { it.dt.base }).forEach {
+                    uninitializedVariable2asm(it)
+                }
+                aligned.sortedWith(compareBy<StStaticVariable> { it.align }.thenBy { it.name }.thenBy { it.dt.base })
+                    .forEach { uninitializedVariable2asm(it) }
+                asmgen.out("  .send $section")
             }
-            aligned.sortedWith(compareBy<StStaticVariable> { it.align }.thenBy { it.name }.thenBy { it.dt.base }).forEach {
-                uninitializedVariable2asm(it)
+
+            if(clean.isNotEmpty()) {
+                // clean vars end up in BSS so they're at least cleared to 0 at startup
+                generate("BSS", clean)
+            }
+            if(dirty.isNotEmpty()) {
+                // Dirty vars actually are ALSO are put into BSS so they're cleared to 0 at program startup,
+                // but NOT at each entry of the subroutine they're declared in.
+                // This saves the STZ's instructions in the subroutine, while still having deterministic start state.
+                // So there is no actual difference here when compared to the way non-dirty variables are allocated.
+                generate("BSS", dirty)
             }
-            asmgen.out("  .send BSS")
         }
 
         if(varsWithInit.isNotEmpty()) {
             asmgen.out("; non-zeropage variables with init value")
             val (stringvars, othervars) = varsWithInit.sortedBy { it.name }.partition { it.dt.isString }
-            val (notAlignedStrings, alignedStrings) = stringvars.partition { it.align==0 }
-            val (notAlignedOther, alignedOther) = othervars.partition { it.align==0 }
+            val (notAlignedStrings, alignedStrings) = stringvars.partition { it.align==0u }
+            val (notAlignedOther, alignedOther) = othervars.partition { it.align==0u }
             notAlignedStrings.forEach {
                 outputStringvar(
                     it.name,
@@ -698,23 +776,27 @@ internal class ProgramAndVarsGen(
             dt.isFloat -> asmgen.out("${variable.name}\t.fill  ${compTarget.FLOAT_MEM_SIZE}")
             dt.isSplitWordArray -> {
                 alignVar(variable.align)
-                val numbytesPerHalf = compTarget.memorySize(variable.dt, variable.length!!) / 2
+                val numbytesPerHalf = compTarget.memorySize(variable.dt, variable.length!!.toInt()) / 2
                 asmgen.out("${variable.name}_lsb\t.fill  $numbytesPerHalf")
                 asmgen.out("${variable.name}_msb\t.fill  $numbytesPerHalf")
             }
             dt.isArray -> {
                 alignVar(variable.align)
-                val numbytes = compTarget.memorySize(variable.dt, variable.length!!)
+                val numbytes = compTarget.memorySize(variable.dt, variable.length!!.toInt())
                 asmgen.out("${variable.name}\t.fill  $numbytes")
             }
+            dt.isPointer -> asmgen.out("${variable.name}\t.word  ?")        // a pointer is just an uword address
+            dt.isPointerArray -> {
+                TODO("pointers are not supported yet")
+            }
             else -> {
                 throw AssemblyError("weird dt")
             }
         }
     }
 
-    private fun alignVar(align: Int) {
-        if(align > 1)
+    private fun alignVar(align: UInt) {
+        if(align > 1u)
             asmgen.out("  .align  ${align.toHex()}")
     }
 
@@ -751,7 +833,7 @@ internal class ProgramAndVarsGen(
                 throw AssemblyError("all string vars should have been interned into prog")
             }
             dt.isArray -> {
-                arrayVariable2asm(variable.name, variable.dt, variable.align, variable.initializationArrayValue, variable.length)
+                arrayVariable2asm(variable.name, variable.dt, variable.align, variable.initializationArrayValue, variable.length?.toInt())
             }
             else -> {
                 throw AssemblyError("weird dt")
@@ -759,7 +841,7 @@ internal class ProgramAndVarsGen(
         }
     }
 
-    private fun arrayVariable2asm(varname: String, dt: DataType, align: Int, value: StArray?, orNumberOfZeros: Int?) {
+    private fun arrayVariable2asm(varname: String, dt: DataType, align: UInt, value: StArray?, orNumberOfZeros: Int?) {
         alignVar(align)
         when {
             dt.isUnsignedByteArray || dt.isBoolArray -> {
@@ -861,7 +943,7 @@ internal class ProgramAndVarsGen(
             }
     }
 
-    private fun outputStringvar(varname: String, align: Int, encoding: Encoding, value: String) {
+    private fun outputStringvar(varname: String, align: UInt, encoding: Encoding, value: String) {
         alignVar(align)
         asmgen.out("$varname\t; $encoding:\"${value.escape().replace("\u0000", "<NULL>")}\"", false)
         val bytes = compTarget.encodeString(value, encoding).plus(0.toUByte())
@@ -926,7 +1008,7 @@ internal class ProgramAndVarsGen(
                     else
                         "-$$hexnum"
                 }
-            dt.isArray && dt.elementType().isUnsignedWord -> array.map {
+            dt.isArray && (dt.elementType().isUnsignedWord || dt.elementType().isPointer) -> array.map {
                 val number = it.number!!.toInt()
                 "$" + number.toString(16).padStart(4, '0')
             }

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

@@ -52,7 +52,7 @@ internal class VariableAllocator(private val symboltable: SymbolTable,
         val varsRequiringZp = allVariables.filter { it.zpwish == ZeropageWish.REQUIRE_ZEROPAGE }
         val varsPreferringZp = allVariables.filter { it.zpwish == ZeropageWish.PREFER_ZEROPAGE }
         val varsNotZp = allVariables.filter { it.zpwish == ZeropageWish.NOT_IN_ZEROPAGE }
-        val (varsDontCareWithoutAlignment, varsDontCareWithAlignment) = allVariables.filter { it.zpwish == ZeropageWish.DONTCARE }.partition { it.align == 0 }
+        val (varsDontCareWithoutAlignment, varsDontCareWithAlignment) = allVariables.filter { it.zpwish == ZeropageWish.DONTCARE }.partition { it.align == 0u }
         require(varsDontCareWithAlignment.size + varsDontCareWithoutAlignment.size + varsRequiringZp.size + varsPreferringZp.size + varsNotZp.size == numberOfAllocatableVariables)
 
         var numVariablesAllocatedInZP = 0
@@ -60,9 +60,9 @@ internal class VariableAllocator(private val symboltable: SymbolTable,
 
         varsRequiringZp.forEach { variable ->
             val result = zeropage.allocate(
-                variable.scopedName,
+                variable.scopedNameString,
                 variable.dt,
-                variable.length,
+                variable.length?.toInt(),
                 variable.astNode?.position ?: Position.DUMMY,
                 errors
             )
@@ -79,9 +79,9 @@ internal class VariableAllocator(private val symboltable: SymbolTable,
         if(errors.noErrors()) {
             varsPreferringZp.forEach { variable ->
                 val result = zeropage.allocate(
-                    variable.scopedName,
+                    variable.scopedNameString,
                     variable.dt,
-                    variable.length,
+                    variable.length?.toInt(),
                     variable.astNode?.position ?: Position.DUMMY,
                     errors
                 )
@@ -92,16 +92,16 @@ internal class VariableAllocator(private val symboltable: SymbolTable,
             // try to allocate the "don't care" interger variables into the zeropage until it is full.
             // TODO some form of intelligent priorization? most often used variables first? loopcounter vars first? ...?
             if(errors.noErrors()) {
-                val sortedList = varsDontCareWithoutAlignment.sortedByDescending { it.scopedName }
+                val sortedList = varsDontCareWithoutAlignment.sortedByDescending { it.scopedNameString }
                 for (variable in sortedList) {
-                    if(variable.dt.isIntegerOrBool) {
+                    if(variable.dt.isIntegerOrBool || variable.dt.isPointer) {
                         if(zeropage.free.isEmpty()) {
                             break
                         } else {
                             val result = zeropage.allocate(
-                                variable.scopedName,
+                                variable.scopedNameString,
                                 variable.dt,
-                                variable.length,
+                                variable.length?.toInt(),
                                 variable.astNode?.position ?: Position.DUMMY,
                                 errors
                             )

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

@@ -20,6 +20,8 @@ internal class AnyExprAsmGen(
     private val asmgen: AsmGen6502Internal
 ) {
     fun assignAnyExpressionUsingStack(expr: PtBinaryExpression, assign: AsmAssignment): Boolean {
+        if(expr.operator==".")
+            throw AssemblyError("pointer deref expression should have been handled elsewhere ${expr.position}")
         when {
             expr.type.isByteOrBool -> {
                 if(expr.left.type.isByteOrBool && expr.right.type.isByteOrBool)
@@ -46,6 +48,12 @@ internal class AnyExprAsmGen(
                 }
                 return assignFloatBinExpr(expr, assign)
             }
+            expr.type.isPointer -> {
+                require((expr.left.type.isPointer || expr.left.type.isUnsignedWord) && (expr.right.type.isPointer || expr.right.type.isUnsignedWord)) {
+                    "both operands must be pointers or uwords"
+                }
+                throw AssemblyError("expression should have been handled otherwise: pointer ${expr.operator} at ${expr.position}")
+            }
             else -> throw AssemblyError("weird expression type in assignment")
         }
     }
@@ -53,7 +61,7 @@ internal class AnyExprAsmGen(
     private fun assignByteBinExpr(expr: PtBinaryExpression, assign: AsmAssignment): Boolean {
         when(expr.operator) {
             "+" -> {
-                asmgen.assignExpressionToRegister(expr.left, RegisterOrPair.A, false)
+                asmgen.assignExpressionToRegister(expr.left, RegisterOrPair.A)
                 asmgen.out("  pha")
                 asmgen.assignExpressionToVariable(expr.right, "P8ZP_SCRATCH_B1", DataType.UBYTE)
                 asmgen.out("  pla |  clc |  adc  P8ZP_SCRATCH_B1")
@@ -61,7 +69,7 @@ internal class AnyExprAsmGen(
                 return true
             }
             "-" -> {
-                asmgen.assignExpressionToRegister(expr.left, RegisterOrPair.A, false)
+                asmgen.assignExpressionToRegister(expr.left, RegisterOrPair.A)
                 asmgen.out("  pha")
                 asmgen.assignExpressionToVariable(expr.right, "P8ZP_SCRATCH_B1", DataType.UBYTE)
                 asmgen.out("  pla |  sec |  sbc  P8ZP_SCRATCH_B1")
@@ -76,7 +84,7 @@ internal class AnyExprAsmGen(
             "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.assignExpressionToRegister(expr.left, RegisterOrPair.A)
                 asmgen.out("  pha")
                 asmgen.assignExpressionToVariable(expr.right, "P8ZP_SCRATCH_B1", DataType.UBYTE)
                 asmgen.out("  pla |  and  P8ZP_SCRATCH_B1")
@@ -84,7 +92,7 @@ internal class AnyExprAsmGen(
                 return true
             }
             "|" -> {
-                asmgen.assignExpressionToRegister(expr.left, RegisterOrPair.A, false)
+                asmgen.assignExpressionToRegister(expr.left, RegisterOrPair.A)
                 asmgen.out("  pha")
                 asmgen.assignExpressionToVariable(expr.right, "P8ZP_SCRATCH_B1", DataType.UBYTE)
                 asmgen.out("  pla |  ora  P8ZP_SCRATCH_B1")
@@ -92,7 +100,7 @@ internal class AnyExprAsmGen(
                 return true
             }
             "^", "xor" -> {
-                asmgen.assignExpressionToRegister(expr.left, RegisterOrPair.A, false)
+                asmgen.assignExpressionToRegister(expr.left, RegisterOrPair.A)
                 asmgen.out("  pha")
                 asmgen.assignExpressionToVariable(expr.right, "P8ZP_SCRATCH_B1", DataType.UBYTE)
                 asmgen.out("  pla |  eor  P8ZP_SCRATCH_B1")

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

@@ -6,11 +6,12 @@ import prog8.codegen.cpu6502.AsmGen6502Internal
 
 
 internal enum class TargetStorageKind {
-    VARIABLE,
+    VARIABLE,       // non-pointer variable
     ARRAY,
     MEMORY,
     REGISTER,
-    VOID       // assign nothing - used in multi-value assigns for void placeholders
+    POINTER,        // wherever the pointer variable points to
+    VOID            // assign nothing - used in multi-value assigns for void placeholders
 }
 
 internal enum class SourceStorageKind {
@@ -32,6 +33,7 @@ internal class AsmAssignTarget(val kind: TargetStorageKind,
                                val array: PtArrayIndexer? = null,
                                val memory: PtMemoryByte? = null,
                                val register: RegisterOrPair? = null,
+                               val pointer: PtPointerDeref? = null,
                                val origAstTarget: PtAssignTarget? = null
                                )
 {
@@ -39,13 +41,24 @@ internal class AsmAssignTarget(val kind: TargetStorageKind,
     val asmVarname: String by lazy {
         if (array == null)
             variableAsmName!!
-        else
-            asmgen.asmVariableName(array.variable)
+        else {
+            if(array.variable==null)
+                TODO("asmVarname for array with pointer")
+            asmgen.asmVariableName(array.variable!!)
+        }
     }
 
     init {
         if(register!=null && !datatype.isNumericOrBool)
             throw AssemblyError("must be numeric type")
+        if(kind==TargetStorageKind.REGISTER)
+            require(register!=null)
+        else
+            require(register==null)
+        if(kind==TargetStorageKind.POINTER)
+            require(pointer!=null)
+        if(pointer!=null)
+            require(kind==TargetStorageKind.POINTER)
     }
 
     companion object {
@@ -77,6 +90,7 @@ internal class AsmAssignTarget(val kind: TargetStorageKind,
                     }
                     array != null -> return AsmAssignTarget(TargetStorageKind.ARRAY, asmgen, type, definingSub, target.position, array = array, origAstTarget =  this)
                     memory != null -> return AsmAssignTarget(TargetStorageKind.MEMORY, asmgen, type, definingSub, target.position, memory =  memory, origAstTarget =  this)
+                    pointerDeref != null -> return AsmAssignTarget(TargetStorageKind.POINTER, asmgen, type, definingSub, target.position, pointer = pointerDeref, origAstTarget =  this)
                     else -> throw AssemblyError("weird target")
                 }
             }
@@ -134,11 +148,14 @@ internal class AsmAssignTarget(val kind: TargetStorageKind,
                 left is PtIdentifier && left.name==scopedName
             }
             TargetStorageKind.ARRAY -> {
-                left is PtArrayIndexer && left isSameAs array!! && left.splitWords==array.splitWords
+                left is PtArrayIndexer && left isSameAs array!! && left.splitWords==array.splitWords && (left.pointerderef==null && array.pointerderef==null || left.pointerderef!! isSameAs array.pointerderef!!)
             }
             TargetStorageKind.MEMORY -> {
                 left isSameAs memory!!
             }
+            TargetStorageKind.POINTER -> {
+                TODO("is pointer deref target same as expression? ${this.position}")
+            }
             TargetStorageKind.REGISTER -> false
             TargetStorageKind.VOID -> false
         }
@@ -160,8 +177,11 @@ internal class AsmAssignSource(val kind: SourceStorageKind,
     val asmVarname: String
         get() = if(array==null)
             variableAsmName!!
-        else
-            asmgen.asmVariableName(array.variable)
+        else {
+            if(array.variable==null)
+                TODO("asmVarname for array with pointer")
+            asmgen.asmVariableName(array.variable!!)
+        }
 
     companion object {
         fun fromAstSource(value: PtExpression, program: PtProgram, asmgen: AsmGen6502Internal): AsmAssignSource {
@@ -203,7 +223,7 @@ internal class AsmAssignSource(val kind: SourceStorageKind,
                     val symbol = asmgen.symbolTable.lookup(value.name) ?: throw AssemblyError("lookup error ${value.name}")
                     val sub = symbol.astNode as IPtSubroutine
                     val returnType =
-                        if(sub is PtSub && sub.returns.size>1)
+                        if(sub is PtSub && sub.signature.returns.size>1)
                             DataType.UNDEFINED      // TODO list of types instead?
                         else
                             sub.returnsWhatWhere().firstOrNull { rr -> rr.first.registerOrPair != null || rr.first.statusflag!=null }?.second

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

@@ -9,6 +9,7 @@ import prog8.codegen.cpu6502.VariableAllocator
 internal class AugmentableAssignmentAsmGen(private val program: PtProgram,
                                            private val assignmentAsmGen: AssignmentAsmGen,
                                            private val asmgen: AsmGen6502Internal,
+                                           private val ptrgen: PointerAssignmentsGen,
                                            private val allocator: VariableAllocator
 ) {
     fun translate(assign: AsmAugmentedAssignment, scope: IPtSubroutine?) {
@@ -84,22 +85,23 @@ internal class AugmentableAssignmentAsmGen(private val program: PtProgram,
                             }
                         }
                     }
-                    target.datatype.isWord -> {
+                    target.datatype.isWord || target.datatype.isPointer -> {
                         val block = target.origAstTarget?.definingBlock()
+                        val targetDt = if(target.datatype.isWord) target.datatype else DataType.UWORD   // pointers themselves that get a new value are just treated as UWORD variables
                         when(value.kind) {
-                            SourceStorageKind.LITERALBOOLEAN -> inplacemodificationWordWithLiteralval(target.asmVarname, target.datatype, operator, value.boolean!!.asInt(), block)
-                            SourceStorageKind.LITERALNUMBER -> inplacemodificationWordWithLiteralval(target.asmVarname, target.datatype, operator, value.number!!.number.toInt(), block)
-                            SourceStorageKind.VARIABLE -> inplacemodificationWordWithVariable(target.asmVarname, target.datatype, operator, value.asmVarname, value.datatype, block)
-                            SourceStorageKind.REGISTER -> inplacemodificationWordWithVariable(target.asmVarname, target.datatype, operator, regName(value), value.datatype, block)
-                            SourceStorageKind.MEMORY -> inplacemodificationWordWithMemread(target.asmVarname, target.datatype, operator, value.memory!!)
-                            SourceStorageKind.ARRAY -> inplacemodificationWordWithValue(target.asmVarname, target.datatype, operator, value.array!!, block)
+                            SourceStorageKind.LITERALBOOLEAN -> inplacemodificationWordWithLiteralval(target.asmVarname, targetDt, operator, value.boolean!!.asInt(), block)
+                            SourceStorageKind.LITERALNUMBER -> inplacemodificationWordWithLiteralval(target.asmVarname, targetDt, operator, value.number!!.number.toInt(), block)
+                            SourceStorageKind.VARIABLE -> inplacemodificationWordWithVariable(target.asmVarname, targetDt, operator, value.asmVarname, value.datatype, block)
+                            SourceStorageKind.REGISTER -> inplacemodificationWordWithVariable(target.asmVarname, targetDt, operator, regName(value), value.datatype, block)
+                            SourceStorageKind.MEMORY -> inplacemodificationWordWithMemread(target.asmVarname, targetDt, operator, value.memory!!)
+                            SourceStorageKind.ARRAY -> inplacemodificationWordWithValue(target.asmVarname, targetDt, operator, value.array!!, block)
                             SourceStorageKind.EXPRESSION -> {
                                 if(value.expression is PtTypeCast) {
                                     if (tryInplaceModifyWithRemovedRedundantCast(value.expression, target, operator)) return
-                                    inplacemodificationWordWithValue(target.asmVarname, target.datatype, operator, value.expression, block)
+                                    inplacemodificationWordWithValue(target.asmVarname, targetDt, operator, value.expression, block)
                                 }
                                 else {
-                                    inplacemodificationWordWithValue(target.asmVarname, target.datatype, operator, value.expression!!, block)
+                                    inplacemodificationWordWithValue(target.asmVarname, targetDt, operator, value.expression!!, block)
                                 }
                             }
                         }
@@ -170,7 +172,7 @@ internal class AugmentableAssignmentAsmGen(private val program: PtProgram,
                         if(memory.address is PtBinaryExpression && tryOptimizedMemoryInplace(memory.address as PtBinaryExpression, operator, value))
                             return
                         // slower method to calculate and use the pointer to access the memory with:
-                        asmgen.assignExpressionToRegister(memory.address, RegisterOrPair.AY, false)
+                        asmgen.assignExpressionToRegister(memory.address, RegisterOrPair.AY)
                         asmgen.saveRegisterStack(CpuRegister.A, true)
                         asmgen.saveRegisterStack(CpuRegister.Y, true)
                         if(asmgen.isTargetCpu(CpuType.CPU65C02))
@@ -205,7 +207,7 @@ internal class AugmentableAssignmentAsmGen(private val program: PtProgram,
                                 asmgen.out("  ldx  P8ZP_SCRATCH_B1")
                             }
                             SourceStorageKind.EXPRESSION -> {
-                                val tempVar = asmgen.getTempVarName(BaseDataType.UBYTE)
+                                val tempVar = asmgen.createTempVarReused(BaseDataType.UBYTE, false, memory)
                                 asmgen.out("  sta  $tempVar")
                                 if(value.expression is PtTypeCast)
                                     inplacemodificationByteWithValue(tempVar, DataType.UBYTE, operator, value.expression)
@@ -224,7 +226,13 @@ internal class AugmentableAssignmentAsmGen(private val program: PtProgram,
                 }
             }
             TargetStorageKind.ARRAY -> {
-                val indexNum = target.array!!.index as? PtNumber
+                val deref = target.array!!.pointerderef
+                if(deref!=null) {
+                    TODO("inplace modification array indexed pointer deref ${target.position}")
+                    return
+                }
+                val targetArrayVar = target.array.variable!!
+                val indexNum = target.array.index as? PtNumber
                 if (indexNum!=null) {
                     val index = indexNum.number.toInt()
                     if(target.array.splitWords) {
@@ -301,7 +309,7 @@ internal class AugmentableAssignmentAsmGen(private val program: PtProgram,
                                 }
                             }
                         }
-
+                        target.datatype.isPointer -> TODO("inplace modification of pointer array ${target.position}")
                         else -> throw AssemblyError("weird type to do in-place modification on ${target.datatype}")
                     }
                 }
@@ -320,7 +328,7 @@ internal class AugmentableAssignmentAsmGen(private val program: PtProgram,
                                 return
                             asmgen.loadScaledArrayIndexIntoRegister(target.array, CpuRegister.Y)
                             asmgen.saveRegisterStack(CpuRegister.Y, false)
-                            asmgen.out("  lda  ${target.array.variable.name},y")
+                            asmgen.out("  lda  ${targetArrayVar.name},y")
                             when(value.kind) {
                                 SourceStorageKind.LITERALBOOLEAN -> {
                                     inplacemodificationRegisterAwithVariable(operator, "#${value.boolean!!.asInt()}", target.datatype.isSigned)
@@ -356,7 +364,7 @@ internal class AugmentableAssignmentAsmGen(private val program: PtProgram,
                                 }
 
                                 SourceStorageKind.EXPRESSION -> {
-                                    val tempVar = asmgen.getTempVarName(BaseDataType.UBYTE)
+                                    val tempVar = asmgen.createTempVarReused(BaseDataType.UBYTE, false, target.array)
                                     asmgen.out("  sta  $tempVar")
                                     if(value.expression is PtTypeCast)
                                         inplacemodificationByteWithValue(tempVar, target.datatype, operator, value.expression)
@@ -366,7 +374,7 @@ internal class AugmentableAssignmentAsmGen(private val program: PtProgram,
                                     asmgen.out("  lda  $tempVar")
                                 }
                             }
-                            asmgen.out("  sta  ${target.array.variable.name},y")
+                            asmgen.out("  sta  ${targetArrayVar.name},y")
                         }
 
                         target.datatype.isWord -> {
@@ -377,11 +385,11 @@ internal class AugmentableAssignmentAsmGen(private val program: PtProgram,
                             asmgen.loadScaledArrayIndexIntoRegister(target.array, CpuRegister.Y)
                             asmgen.saveRegisterStack(CpuRegister.Y, false)
                             if(target.array.splitWords) {
-                                asmgen.out("  lda  ${target.array.variable.name}_lsb,y")
-                                asmgen.out("  ldx  ${target.array.variable.name}_msb,y")
+                                asmgen.out("  lda  ${targetArrayVar.name}_lsb,y")
+                                asmgen.out("  ldx  ${targetArrayVar.name}_msb,y")
                             } else {
-                                asmgen.out("  lda  ${target.array.variable.name},y")
-                                asmgen.out("  ldx  ${target.array.variable.name}+1,y")
+                                asmgen.out("  lda  ${targetArrayVar.name},y")
+                                asmgen.out("  ldx  ${targetArrayVar.name}+1,y")
                             }
                             val block = target.origAstTarget?.definingBlock()
                             when(value.kind) {
@@ -439,7 +447,7 @@ internal class AugmentableAssignmentAsmGen(private val program: PtProgram,
                                 }
 
                                 SourceStorageKind.EXPRESSION -> {
-                                    val tempVar = asmgen.getTempVarName(BaseDataType.UWORD)
+                                    val tempVar = asmgen.createTempVarReused(BaseDataType.UWORD, false, target.array)
                                     asmgen.out("  sta  $tempVar |  stx  $tempVar+1")
                                     if(value.expression is PtTypeCast)
                                         inplacemodificationWordWithValue(tempVar, target.datatype, operator, value.expression, block)
@@ -450,14 +458,14 @@ internal class AugmentableAssignmentAsmGen(private val program: PtProgram,
                             }
                             asmgen.restoreRegisterStack(CpuRegister.Y, true)
                             if(target.array.splitWords)
-                                asmgen.out("  sta  ${target.array.variable.name}_lsb,y |  txa |  sta  ${target.array.variable.name}_msb,y")
+                                asmgen.out("  sta  ${targetArrayVar.name}_lsb,y |  txa |  sta  ${targetArrayVar.name}_msb,y")
                             else
-                                asmgen.out("  sta  ${target.array.variable.name},y |  txa |  sta  ${target.array.variable.name}+1,y")
+                                asmgen.out("  sta  ${targetArrayVar.name},y |  txa |  sta  ${targetArrayVar.name}+1,y")
                         }
 
                         target.datatype.isFloat -> {
                             // copy array value into tempvar
-                            val tempvar = asmgen.getTempVarName(BaseDataType.FLOAT)
+                            val tempvar = asmgen.createTempVarReused(BaseDataType.FLOAT, false, target.array)
                             asmgen.loadScaledArrayIndexIntoRegister(target.array, CpuRegister.A)
                             asmgen.out("""
                                                 ldy  #>${target.asmVarname}
@@ -504,18 +512,24 @@ internal class AugmentableAssignmentAsmGen(private val program: PtProgram,
                                                 pla  ; restore array ptr lsb
                                                 jsr  floats.copy_float""")
                         }
-
+                        target.datatype.isPointer -> ptrgen.inplaceModification(PtrTarget(target), operator, value)
                         else -> throw AssemblyError("weird type to do in-place modification on ${target.datatype}")
                     }
                 }
             }
+            TargetStorageKind.POINTER -> ptrgen.inplaceModification(PtrTarget(target), operator, value)
             TargetStorageKind.REGISTER -> throw AssemblyError("no asm gen for reg in-place modification")
             TargetStorageKind.VOID -> { /* do nothing */ }
         }
     }
 
     private fun tryIndexedIncDec(array: PtArrayIndexer, operator: String): Boolean {
-        val arrayvar = asmgen.asmVariableName(array.variable)
+        val arrayVar = array.variable
+        if(arrayVar==null) {
+            TODO("indexed inc/dec on pointer ${array.position}")
+            return false
+        }
+        val arrayvar = asmgen.asmVariableName(arrayVar)
         when {
             array.type.isByte -> {
                 asmgen.loadScaledArrayIndexIntoRegister(array, CpuRegister.X)
@@ -583,7 +597,7 @@ internal class AugmentableAssignmentAsmGen(private val program: PtProgram,
             if(address.left is PtIdentifier && asmgen.isZpVar(address.left as PtIdentifier)) {
                 return (address.left as PtIdentifier).name
             } else {
-                asmgen.assignExpressionToRegister(address.left, RegisterOrPair.AY, false)
+                asmgen.assignExpressionToRegister(address.left, RegisterOrPair.AY)
                 asmgen.out("  sta  P8ZP_SCRATCH_W2 |  sty  P8ZP_SCRATCH_W2+1")
                 return "P8ZP_SCRATCH_W2"
             }
@@ -635,9 +649,9 @@ internal class AugmentableAssignmentAsmGen(private val program: PtProgram,
                 return true
             }
             if(rightTc!=null)
-                asmgen.assignExpressionToRegister(rightTc.value, RegisterOrPair.A, false)
+                asmgen.assignExpressionToRegister(rightTc.value, RegisterOrPair.A)
             else
-                asmgen.assignExpressionToRegister(address.right, RegisterOrPair.A, false)
+                asmgen.assignExpressionToRegister(address.right, RegisterOrPair.A)
             asmgen.out("  pha")     // offset on stack
             val zpPointerVarName = addrIntoZpPointer()
             assignValueToA()
@@ -884,7 +898,7 @@ internal class AugmentableAssignmentAsmGen(private val program: PtProgram,
     }
 
     private fun tryInplaceModifyWithRemovedRedundantCast(value: PtTypeCast, target: AsmAssignTarget, operator: String): Boolean {
-        if (target.datatype == value.type) {
+        if (target.datatype == value.type || (target.datatype.isPointer && value.type.isWord)) {
             val childDt = value.value.type
             if (!value.type.isFloat && (value.type.equalsSize(childDt) || value.type.largerSizeThan(childDt))) {
                 // this typecast is redundant here; the rest of the code knows how to deal with the uncasted value.
@@ -910,7 +924,7 @@ internal class AugmentableAssignmentAsmGen(private val program: PtProgram,
             "-" -> asmgen.out("  sec |  sbc  $otherName")
             "*" -> asmgen.out("  ldy  $otherName |  jsr  prog8_math.multiply_bytes")
             "/" -> asmgen.out("  ldy  $otherName |  jsr  prog8_math.divmod_ub_asm |  tya")
-            "%" -> asmgen.out("  ldy  $otherName |  jsr  prog8_math.divmod_ub_asm")
+            "%" -> asmgen.out("  ldy  $otherName |  jsr  prog8_math.remainder_ub_asm")
             "<<" -> {
                 asmgen.out("""
                         ldy  $otherName
@@ -972,7 +986,7 @@ internal class AugmentableAssignmentAsmGen(private val program: PtProgram,
                     } else {
                         asmgen.assignExpressionToRegister(pointervar, RegisterOrPair.AY)
                         asmgen.out("  sta  (+) + 1 |  sty  (+) + 2")
-                        asmgen.out("+\tinc  ${'$'}ffff\t; modified")
+                        asmgen.out($$"+\tinc  $ffff\t; modified")
                     }
                 } else {
                     val sourceName = asmgen.loadByteFromPointerIntoA(pointervar)
@@ -992,7 +1006,7 @@ internal class AugmentableAssignmentAsmGen(private val program: PtProgram,
                     } else {
                         asmgen.assignExpressionToRegister(pointervar, RegisterOrPair.AY)
                         asmgen.out("  sta  (+) + 1 |  sty  (+) + 2")
-                        asmgen.out("+\tdec  ${'$'}ffff\t; modified")
+                        asmgen.out($$"+\tdec  $ffff\t; modified")
                     }
                 } else {
                     val sourceName = asmgen.loadByteFromPointerIntoA(pointervar)
@@ -1019,7 +1033,7 @@ internal class AugmentableAssignmentAsmGen(private val program: PtProgram,
                 val sourceName = asmgen.loadByteFromPointerIntoA(pointervar)
                 if(value==0)
                     throw AssemblyError("division by zero")
-                asmgen.out("  ldy  #$value |  jsr  prog8_math.divmod_ub_asm")
+                asmgen.out("  ldy  #$value |  jsr  prog8_math.remainder_ub_asm")
                 asmgen.storeAIntoZpPointerVar(sourceName, false)
             }
             "<<" -> {
@@ -1125,11 +1139,18 @@ $shortcutLabel:""")
         }
 
         if(value is PtArrayIndexer && value.isSimple()) {
+
+            val valueVar = value.variable
+            if(valueVar==null) {
+                TODO("inplace modification on pointer ${value.position}")
+                return
+            }
+
             // use the already existing optimized codegen for regular assignments  x += array[index]
             val binexpr = PtBinaryExpression(operator, dt, value.position)
             binexpr.add(PtIdentifier(name, dt, value.position))
             val arrayValue = PtArrayIndexer(value.type, value.position)
-            arrayValue.add(value.variable)
+            arrayValue.add(valueVar)
             arrayValue.add(value.index)
             binexpr.add(arrayValue)
             binexpr.parent = value
@@ -1190,7 +1211,7 @@ $shortcutLabel:""")
             "%" -> {
                 if(signed)
                     throw AssemblyError("remainder of signed integers is not properly defined/implemented, use unsigned instead")
-                asmgen.out("  ldy  $variable  |  jsr  prog8_math.divmod_ub_asm")
+                asmgen.out("  ldy  $variable  |  jsr  prog8_math.remainder_ub_asm")
             }
             "<<" -> {
                 asmgen.out("""
@@ -1363,7 +1384,7 @@ $shortcutLabel:""")
             "%" -> {
                 if(signed)
                     throw AssemblyError("remainder of signed integers is not properly defined/implemented, use unsigned instead")
-                asmgen.out("  tay |  lda  $variable  |  jsr  prog8_math.divmod_ub_asm")
+                asmgen.out("  tay |  lda  $variable  |  jsr  prog8_math.remainder_ub_asm")
             }
             "<<" -> {
                 asmgen.out("""
@@ -1534,7 +1555,7 @@ $shortcutLabel:""")
                 asmgen.out("""
                     lda  $name
                     ldy  #$value
-                    jsr  prog8_math.divmod_ub_asm
+                    jsr  prog8_math.remainder_ub_asm
                     sta  $name""")
             }
             "<<" -> {
@@ -1921,18 +1942,16 @@ $shortcutLabel:""")
                             asmgen.out("  lda  #0 |  sta  $lsb")
                     }
                     value==7 -> {
-                        // optimized shift left 7 (*128) by first swapping the lsb/msb and then doing just one final shift
+                        // optimized shift left 7 (*128) by swapping the lsb/msb and then doing just one final shift
                         asmgen.out("""
                             ; shift left 7
                             lsr  $msb
-                            php     ; save carry
                             lda  $lsb
+                            ror  a
                             sta  $msb
                             lda  #0
-                            sta  $lsb
-                            plp     ; restore carry
-                            ror  $msb
-                            ror  $lsb""")
+                            ror  a
+                            sta  $lsb""")
                     }
                     value>3 -> asmgen.out("""
                         ldy  #$value
@@ -2258,7 +2277,7 @@ $shortcutLabel:""")
 
     private fun inplacemodificationWordWithVariable(name: String, dt: DataType, operator: String, otherName: String, valueDt: DataType, block: PtBlock?) {
         require(dt.isWord)
-        require(valueDt.isInteger)
+        require(valueDt.isInteger || valueDt.isPointer)
         when {
             valueDt.isByte -> {
                 // the other variable is a BYTE type so optimize for that
@@ -2468,7 +2487,7 @@ $shortcutLabel:""")
                     else -> throw AssemblyError("invalid operator for in-place modification $operator")
                 }
             }
-            valueDt.isWord -> {
+            valueDt.isWord || valueDt.isPointer -> {
                 // the value is a proper 16-bit word, so use both bytes of it.
                 when (operator) {
                     "+" -> asmgen.out("  lda  $name |  clc |  adc  $otherName |  sta  $name |  lda  $name+1 |  adc  $otherName+1 |  sta  $name+1")
@@ -2740,7 +2759,7 @@ $shortcutLabel:""")
                     "+" -> {
                         // name += byteexpression
                         if(valueDt.isUnsignedByte) {
-                            asmgen.assignExpressionToRegister(value, RegisterOrPair.A, false)
+                            asmgen.assignExpressionToRegister(value, RegisterOrPair.A)
                             asmgen.out("""
                                 clc
                                 adc  $name
@@ -2890,7 +2909,7 @@ $shortcutLabel:""")
                     else -> throw AssemblyError("invalid operator for in-place modification $operator")
                 }
             }
-            valueDt.isWord -> {
+            valueDt.isWord || valueDt.isPointer -> {
                 // the value is a proper 16-bit word, so use both bytes of it.
 
                 if(value is PtArrayIndexer && value.isSimple()) {
@@ -2905,7 +2924,12 @@ $shortcutLabel:""")
                         "-" -> {
                             if(value.index.type.isByte) {
                                 // it's an array indexed by a byte so we can use sbc array,y
-                                val arrayname = value.variable.name
+                                val valueVar = value.variable
+                                if(valueVar==null) {
+                                    TODO("inplace modification on pointer ${value.position}")
+                                    return
+                                }
+                                val arrayname = valueVar.name
                                 asmgen.loadScaledArrayIndexIntoRegister(value, CpuRegister.Y)
                                 if(value.splitWords) {
                                     asmgen.out("""

codeGenCpu6502/test/Dummies.kt

@@ -5,7 +5,9 @@ import prog8.code.core.*
 
 internal object DummyMemsizer : IMemSizer {
     override fun memorySize(dt: DataType, numElements: Int?): Int {
-        if(dt.isArray) {
+        if(dt.isPointerArray)
+            return 2 * numElements!!
+        else if(dt.isArray) {
             require(numElements != null)
             return when(dt.sub) {
                 BaseDataType.BOOL, BaseDataType.BYTE, BaseDataType.UBYTE -> numElements
@@ -68,7 +70,7 @@ internal class ErrorReporterForTests(private val throwExceptionAtReportIfErrors:
 
     override fun noErrors(): Boolean  = errors.isEmpty()
     override fun noErrorForLine(position: Position) = !errors.any { ":${position.line}:" in it }
-    override fun print_single_error(errormessage: String) { /* prints nothing in tests */ }
+    override fun printSingleError(errormessage: String) { /* prints nothing in tests */ }
 
     override fun report() {
         infos.forEach { println("UNITTEST COMPILATION REPORT: INFO: $it") }

codeGenCpu6502/test/TestCodegen.kt

@@ -58,6 +58,7 @@ class TestCodegen: FunSpec({
             DataType.UBYTE,
             ZeropageWish.DONTCARE,
             0u,
+            false,
             null,
             null,
             Position.DUMMY
@@ -67,6 +68,7 @@ class TestCodegen: FunSpec({
             DataType.arrayFor(BaseDataType.UBYTE),
             ZeropageWish.DONTCARE,
             0u,
+            false,
             null,
             3u,
             Position.DUMMY
@@ -76,6 +78,7 @@ class TestCodegen: FunSpec({
             DataType.arrayFor(BaseDataType.UBYTE),
             ZeropageWish.DONTCARE,
             0u,
+            false,
             null,
             3u,
             Position.DUMMY
@@ -85,6 +88,7 @@ class TestCodegen: FunSpec({
             DataType.WORD,
             ZeropageWish.DONTCARE,
             0u,
+            false,
             null,
             null,
             Position.DUMMY

codeGenExperimental/build.gradle.kts

@@ -1,5 +1,3 @@
-import org.jetbrains.kotlin.gradle.dsl.JvmTarget
-
 plugins {
     kotlin("jvm")
 }
@@ -11,7 +9,7 @@ dependencies {
     implementation(project(":codeGenIntermediate"))
     // implementation("org.jetbrains.kotlin:kotlin-stdlib-jdk8")
     // implementation "org.jetbrains.kotlin:kotlin-reflect"
-    implementation("com.michael-bull.kotlin-result:kotlin-result-jvm:2.0.1")
+    implementation("com.michael-bull.kotlin-result:kotlin-result-jvm:2.1.0")
 }
 
 sourceSets {

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

@@ -1,10 +1,10 @@
 package prog8.codegen.experimental
 
+import prog8.code.IAssemblyProgram
+import prog8.code.ICodeGeneratorBackend
 import prog8.code.SymbolTable
 import prog8.code.ast.PtProgram
 import prog8.code.core.CompilationOptions
-import prog8.code.IAssemblyProgram
-import prog8.code.ICodeGeneratorBackend
 import prog8.code.core.IErrorReporter
 import prog8.codegen.intermediate.IRCodeGen
 import prog8.intermediate.IRFileWriter
@@ -26,7 +26,8 @@ class ExperiCodeGen: ICodeGeneratorBackend {
         // this stub only writes the IR program to disk but doesn't generate anything else.
         IRFileWriter(irProgram, null).write()
 
-        println("** experimental codegen stub: no assembly generated **")
+        if(!options.quiet)
+            println("** experimental codegen stub: no assembly generated **")
         return EmptyProgram
     }
 }
@@ -34,7 +35,8 @@ class ExperiCodeGen: ICodeGeneratorBackend {
 private object EmptyProgram : IAssemblyProgram {
     override val name = "<Empty Program>"
     override fun assemble(options: CompilationOptions, errors: IErrorReporter): Boolean {
-        println("** nothing assembled **")
+        if(!options.quiet)
+            println("** nothing assembled **")
         return true
     }
 

codeGenIntermediate/build.gradle.kts

@@ -1,5 +1,3 @@
-import org.jetbrains.kotlin.gradle.dsl.JvmTarget
-
 plugins {
     kotlin("jvm")
 }
@@ -11,12 +9,10 @@ dependencies {
     implementation(project(":intermediate"))
     // implementation("org.jetbrains.kotlin:kotlin-stdlib-jdk8")
     // implementation "org.jetbrains.kotlin:kotlin-reflect"
-    implementation("com.michael-bull.kotlin-result:kotlin-result-jvm:2.0.1")
+    implementation("com.michael-bull.kotlin-result:kotlin-result-jvm:2.1.0")
 
     testImplementation("io.kotest:kotest-runner-junit5-jvm:5.9.1")
-    testImplementation("org.junit.jupiter:junit-jupiter:5.9.1")
     testImplementation("io.kotest:kotest-framework-datatest:5.9.1")
-    testRuntimeOnly("org.junit.platform:junit-platform-launcher")
 }
 
 sourceSets {

codeGenIntermediate/codeGenIntermediate.iml

@@ -13,9 +13,8 @@
     <orderEntry type="module" module-name="codeCore" />
     <orderEntry type="module" module-name="simpleAst" />
     <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="io.kotest.framework.datatest" level="project" />
     <orderEntry type="library" name="michael.bull.kotlin.result.jvm" level="project" />
+    <orderEntry type="library" name="io.kotest.framework.datatest" level="project" />
   </component>
 </module>

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

@@ -1,8 +1,10 @@
 package prog8.codegen.intermediate
 
+import prog8.code.SymbolTable
 import prog8.code.ast.*
 import prog8.code.core.AssemblyError
 import prog8.code.core.BaseDataType
+import prog8.code.core.DataType
 import prog8.intermediate.*
 
 
@@ -26,9 +28,12 @@ internal class BuiltinFuncGen(private val codeGen: IRCodeGen, private val exprGe
             "lsb" -> funcLsb(call)
             "memory" -> funcMemory(call)
             "peek" -> funcPeek(call, IRDataType.BYTE)
+            "peekbool" -> funcPeek(call, IRDataType.BYTE)
             "peekw" -> funcPeek(call, IRDataType.WORD)
             "peekf" -> funcPeek(call, IRDataType.FLOAT)
             "poke" -> funcPoke(call, IRDataType.BYTE)
+            "pokebool" -> funcPoke(call, IRDataType.BYTE)
+            "pokebowl" -> funcPoke(call, IRDataType.BYTE)
             "pokew" -> funcPoke(call, IRDataType.WORD)
             "pokef" -> funcPoke(call, IRDataType.FLOAT)
             "pokemon" -> funcPokemon(call)
@@ -45,6 +50,8 @@ internal class BuiltinFuncGen(private val codeGen: IRCodeGen, private val exprGe
             "prog8_lib_stringcompare" -> funcStringCompare(call)
             "prog8_lib_square_byte" -> funcSquare(call, IRDataType.BYTE)
             "prog8_lib_square_word" -> funcSquare(call, IRDataType.WORD)
+            "prog8_lib_structalloc" -> funcStructAlloc(call)
+            "sizeof" -> throw AssemblyError("sizeof must have been replaced with a constant")
             else -> throw AssemblyError("missing builtinfunc for ${call.name}")
         }
     }
@@ -78,7 +85,6 @@ internal class BuiltinFuncGen(private val codeGen: IRCodeGen, private val exprGe
 
     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])
@@ -91,7 +97,6 @@ internal class BuiltinFuncGen(private val codeGen: IRCodeGen, private val exprGe
 
     private fun funcCallfar2(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 argumentA = exprGen.translateExpression(call.args[2])
@@ -143,7 +148,6 @@ 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)
@@ -240,11 +244,11 @@ internal class BuiltinFuncGen(private val codeGen: IRCodeGen, private val exprGe
             }
             BaseDataType.UWORD -> {
                 addToResult(result, tr, tr.resultReg, -1)
-                val resultReg = codeGen.registers.next(IRDataType.WORD)
+                val resultReg = codeGen.registers.next(IRDataType.BYTE)     // sqrt of a word still produces just a byte result
                 result += IRCodeChunk(null, null).also {
                     it += IRInstruction(Opcode.SQRT, IRDataType.WORD, reg1=resultReg, reg2=tr.resultReg)
                 }
-                return ExpressionCodeResult(result, IRDataType.WORD, resultReg, -1)
+                return ExpressionCodeResult(result, IRDataType.BYTE, resultReg, -1)
             }
             BaseDataType.FLOAT -> {
                 addToResult(result, tr, -1, tr.resultFpReg)
@@ -278,7 +282,6 @@ internal class BuiltinFuncGen(private val codeGen: IRCodeGen, private val exprGe
 
     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])
@@ -497,8 +500,16 @@ internal class BuiltinFuncGen(private val codeGen: IRCodeGen, private val exprGe
         val name = (call.args[0] as PtString).value
         val code = IRCodeChunk(null, null)
         val resultReg = codeGen.registers.next(IRDataType.WORD)
-        code += IRInstruction(Opcode.LOAD, IRDataType.WORD, reg1=resultReg, labelSymbol = "prog8_slabs.prog8_memoryslab_$name")
-        return ExpressionCodeResult(code, IRDataType.BYTE, resultReg, -1)
+        code += IRInstruction(Opcode.LOAD, IRDataType.WORD, reg1=resultReg, labelSymbol = "$StMemorySlabPrefix.prog8_memoryslab_$name")
+        return ExpressionCodeResult(code, IRDataType.WORD, resultReg, -1)
+    }
+
+    private fun funcStructAlloc(call: PtBuiltinFunctionCall): ExpressionCodeResult {
+        val code = IRCodeChunk(null, null)
+        val resultReg = codeGen.registers.next(IRDataType.WORD)
+        val labelname = SymbolTable.labelnameForStructInstance(call)
+        code += IRInstruction(Opcode.LOAD, IRDataType.WORD, reg1=resultReg, labelSymbol = labelname)
+        return ExpressionCodeResult(code, IRDataType.WORD, resultReg, -1)
     }
 
     private fun funcLsb(call: PtBuiltinFunctionCall): ExpressionCodeResult {
@@ -548,7 +559,9 @@ internal class BuiltinFuncGen(private val codeGen: IRCodeGen, private val exprGe
         val arr = (arg as? PtArrayIndexer)
         val index = arr?.index?.asConstInteger()
         if(arr!=null && index!=null) {
-            val variable = arr.variable.name
+            if(arr.variable==null)
+                TODO("support for ptr indexing ${arr.position}")
+            val variable = arr.variable!!.name
             if(arr.splitWords) {
                 result += IRCodeChunk(null, null).also {
                     when(opcodeMemAndReg.first) {
@@ -617,7 +630,9 @@ internal class BuiltinFuncGen(private val codeGen: IRCodeGen, private val exprGe
                 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(target.variable==null)
+                        TODO("support for ptr indexing ${target.position}")
+                    val varName = target.variable!!.name + if(msb) "_msb" else "_lsb"
                     if(isConstZeroValue) {
                         if(constIndex!=null) {
                             val offsetReg = codeGen.registers.next(IRDataType.BYTE)
@@ -651,6 +666,8 @@ internal class BuiltinFuncGen(private val codeGen: IRCodeGen, private val exprGe
                     }
                 }
                 else {
+                    val targetVariable = target.variable ?: TODO("support for ptr indexing ${target.position}")
+
                     val eltSize = codeGen.program.memsizer.memorySize(target.type, null)
                     val constIndex = target.index.asConstInteger()
                     if(isConstZeroValue) {
@@ -659,17 +676,17 @@ internal class BuiltinFuncGen(private val codeGen: IRCodeGen, private val exprGe
                             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)
+                                it += IRInstruction(Opcode.STOREZX, IRDataType.BYTE, reg1=offsetReg, labelSymbol = targetVariable.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)
+                                    it += codeGen.multiplyByConst(DataType.UBYTE, 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)
+                                it += IRInstruction(Opcode.STOREZX, IRDataType.BYTE, reg1=indexTr.resultReg, labelSymbol = targetVariable.name)
                             }
                         }
                     } else {
@@ -680,17 +697,17 @@ internal class BuiltinFuncGen(private val codeGen: IRCodeGen, private val exprGe
                             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)
+                                it += IRInstruction(Opcode.STOREX, IRDataType.BYTE, reg1=valueTr.resultReg, reg2=offsetReg, labelSymbol = targetVariable.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)
+                                    it += codeGen.multiplyByConst(DataType.UBYTE, 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)
+                                it += IRInstruction(Opcode.STOREX, IRDataType.BYTE, reg1=valueTr.resultReg, reg2=indexTr.resultReg, labelSymbol = targetVariable.name)
                             }
                         }
                     }

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

@@ -1,14 +1,8 @@
 package prog8.codegen.intermediate
 
-import prog8.code.StExtSub
-import prog8.code.StNode
-import prog8.code.StNodeType
-import prog8.code.StSub
+import prog8.code.*
 import prog8.code.ast.*
-import prog8.code.core.AssemblyError
-import prog8.code.core.BaseDataType
-import prog8.code.core.Cx16VirtualRegisters
-import prog8.code.core.Statusflag
+import prog8.code.core.*
 import prog8.intermediate.*
 
 
@@ -92,12 +86,107 @@ internal class ExpressionGen(private val codeGen: IRCodeGen) {
             is PtBuiltinFunctionCall -> codeGen.translateBuiltinFunc(expr)
             is PtFunctionCall -> translate(expr)
             is PtContainmentCheck -> translate(expr)
+            is PtPointerDeref -> translate(expr)
             is PtRange,
             is PtArray,
             is PtString -> throw AssemblyError("range/arrayliteral/string should no longer occur as expression")
         }
     }
 
+    private fun translate(deref: PtPointerDeref): ExpressionCodeResult {
+        val result = mutableListOf<IRCodeChunkBase>()
+        var pointerReg: Int
+
+        if(deref.startpointer.type.isStructInstance) {
+            TODO("translate structinstance deref???")
+/*
+            val arrayIndexer = deref.startpointer as? PtArrayIndexer
+            if(arrayIndexer==null)
+                throw AssemblyError("when start pointer is struct instance, array indexer is expected PTR[x]")
+            // first evaluate the adress of POINTER[x].a
+            // which is: value in pointer + x*sizeof(struct) + offsetof(a)
+            // then use traverseDerefChainToCalculateFinalAddress on b.c.d.field
+            val struct = deref.startpointer.type.subType as StStruct
+            val chain = ArrayDeque(deref.chain)
+            val firstField = struct.getField(chain.removeFirst(), codeGen.program.memsizer)
+            val pointerTr = translateExpression(arrayIndexer.variable)
+            result += pointerTr.chunks
+            pointerReg = pointerTr.resultReg
+            val constIndex = arrayIndexer.index.asConstInteger()
+            if(constIndex!=null) {
+                val offset = constIndex * struct.size.toInt()
+                addInstr(result, IRInstruction(Opcode.ADD, IRDataType.WORD, reg1 = pointerReg, immediate = offset), null)
+            } else {
+                val indexTr = translateExpression(arrayIndexer.index)
+                result += indexTr.chunks
+                // multiply the index by the size of the struct and add that to the pointer, then add the offset of the field,
+                // and retrieve the pointer value that is stored there, or the actual value if it's a pointer to simple type
+                result += IRCodeChunk(null, null).also {
+                    val indexReg: Int
+                    if(arrayIndexer.index.type.isByte) {
+                        // extend array index to word
+                        indexReg = codeGen.registers.next(IRDataType.WORD)
+                        it += IRInstruction(Opcode.EXT, IRDataType.BYTE, indexReg, indexTr.resultReg)
+                    } else {
+                        indexReg = indexTr.resultReg
+                    }
+                    it += codeGen.multiplyByConst(DataType.UWORD, indexReg, struct.size.toInt())
+                    it += IRInstruction(Opcode.ADDR, IRDataType.WORD, reg1 = pointerReg, reg2 = indexReg)
+                }
+            }
+
+            result += IRCodeChunk(null, null).also {
+                it += IRInstruction(Opcode.ADD, IRDataType.WORD, reg1 = pointerReg, immediate = firstField.second.toInt())
+                if (firstField.first.isPointer) {
+                    // get the address stored in the pointer and use that for the rest of the chain
+                    // LOADI has an exception to allo reg1 and reg2 to be the same, so we can avoid using extra temporary registers and LOADS
+                    it += IRInstruction(Opcode.LOADI, IRDataType.WORD, reg1 = pointerReg, reg2 = pointerReg)
+                } else {
+                    require(chain.isEmpty())
+                    // it's a pointer to a simple value, so keep the pointer as-is
+                }
+            }
+
+
+            // now use traverseDerefChainToCalculateFinalAddress on b.c.d and finally field  or on b.c.d.field if field isn't a field.
+            val derefField = if(deref.type.isPointer) null else chain.removeLastOrNull()
+            actualDeref = PtPointerDeref(deref.type, chain, derefField, deref.position)
+            actualDeref.add(arrayIndexer.variable)
+*/
+        } else {
+            val tr = translateExpression(deref.startpointer)
+            result += tr.chunks
+            pointerReg = tr.resultReg
+        }
+
+        val (instructions, offset) = traverseRestOfDerefChainToCalculateFinalAddress(deref, pointerReg)
+        result += instructions
+        if(offset==0u) {
+            val irdt = irType(deref.type)
+            return if(deref.type.isFloat) {
+                val resultReg = codeGen.registers.next(IRDataType.FLOAT)
+                addInstr(result, IRInstruction(Opcode.LOADI, IRDataType.FLOAT, fpReg1 = resultReg, reg1 = pointerReg), null)
+                ExpressionCodeResult(result, IRDataType.FLOAT, -1, resultReg)
+            } else {
+                val resultReg = codeGen.registers.next(irdt)
+                addInstr(result, IRInstruction(Opcode.LOADI, irdt, reg1 = resultReg, reg2 = pointerReg), null)
+                ExpressionCodeResult(result, irdt, resultReg, -1)
+            }
+        }
+
+        // load field with offset
+        return if(deref.type.isFloat) {
+            val resultReg = codeGen.registers.next(IRDataType.FLOAT)
+            addInstr(result, IRInstruction(Opcode.LOADFIELD, IRDataType.FLOAT, fpReg1 = resultReg, reg1 = pointerReg, immediate = offset.toInt()), null)
+            ExpressionCodeResult(result, IRDataType.FLOAT, -1, resultReg)
+        } else {
+            val irdt = irType(deref.type)
+            val resultReg = codeGen.registers.next(irdt)
+            addInstr(result, IRInstruction(Opcode.LOADFIELD, irdt, reg1 = resultReg, reg2 = pointerReg, immediate = offset.toInt()), null)
+            ExpressionCodeResult(result, irdt, resultReg, -1)
+        }
+    }
+
     private fun translate(ifExpr: PtIfExpression): ExpressionCodeResult {
 
         if((ifExpr.condition as? PtPrefix)?.operator=="not")
@@ -166,46 +255,77 @@ internal class ExpressionGen(private val codeGen: IRCodeGen) {
 
     private fun translate(expr: PtAddressOf): ExpressionCodeResult {
         val vmDt = irType(expr.type)
-        val symbol = expr.identifier.name
         // note: LOAD <symbol>  gets you the address of the symbol, whereas LOADM <symbol> would get you the value stored at that location
         val result = mutableListOf<IRCodeChunkBase>()
-        val resultRegister = codeGen.registers.next(vmDt)
+        val identifier = expr.identifier
 
         fun loadAddressOfArrayLabel(reg: Int) {
             if (expr.isMsbForSplitArray) {
-                addInstr(result, IRInstruction(Opcode.LOAD, vmDt, reg1 = reg, labelSymbol = symbol + "_msb"), null)
-            } else if (expr.identifier.type.isSplitWordArray) {
+                addInstr(result, IRInstruction(Opcode.LOAD, vmDt, reg1 = reg, labelSymbol = identifier!!.name + "_msb"), null)
+            } else if (identifier!!.type.isSplitWordArray) {
                 // the _lsb split array comes first in memory
-                addInstr(result, IRInstruction(Opcode.LOAD, vmDt, reg1 = reg, labelSymbol = symbol + "_lsb"), null)
+                addInstr(result, IRInstruction(Opcode.LOAD, vmDt, reg1 = reg, labelSymbol = identifier.name + "_lsb"), null)
             } else
-                addInstr(result, IRInstruction(Opcode.LOAD, vmDt, reg1 = reg, labelSymbol = symbol), null)
+                addInstr(result, IRInstruction(Opcode.LOAD, vmDt, reg1 = reg, labelSymbol = identifier.name), null)
         }
 
         if(expr.isFromArrayElement) {
             val indexTr = translateExpression(expr.arrayIndexExpr!!)
             addToResult(result, indexTr, indexTr.resultReg, -1)
-            val indexWordReg = codeGen.registers.next(IRDataType.WORD)
-            addInstr(result, IRInstruction(Opcode.EXT, IRDataType.BYTE, reg1=indexWordReg, reg2=indexTr.resultReg), null)
-            if(expr.identifier.type.isUnsignedWord) {
+            val indexWordReg = if(indexTr.dt==IRDataType.BYTE) {
+                val ixWord = codeGen.registers.next(IRDataType.WORD)
+                addInstr(result, IRInstruction(Opcode.EXT, IRDataType.BYTE, reg1=ixWord, reg2=indexTr.resultReg), null)
+                ixWord
+            } else indexTr.resultReg
+            val resultRegister = codeGen.registers.next(vmDt)
+            if(identifier!!.type.isUnsignedWord) {
                 require(!expr.isMsbForSplitArray)
                 result += IRCodeChunk(null, null).also {
-                    it += IRInstruction(Opcode.LOADM, vmDt, reg1 = resultRegister, labelSymbol = symbol)
+                    val ptr = codeGen.symbolTable.lookup(identifier.name)
+                    it += if(ptr is StConstant)
+                        IRInstruction(Opcode.LOAD, vmDt, reg1 = resultRegister, immediate = ptr.value.toInt())
+                    else
+                        IRInstruction(Opcode.LOADM, vmDt, reg1 = resultRegister, labelSymbol = identifier.name)
                     it += IRInstruction(Opcode.ADDR, IRDataType.WORD, reg1=resultRegister, reg2=indexWordReg)
                 }
+            } else if(identifier.type.isPointer) {
+                // apply pointer arithmetic for the array indexing
+                val eltSize = if(identifier.type.sub!=null)
+                        codeGen.program.memsizer.memorySize(identifier.type.sub!!)
+                    else
+                        identifier.type.subType!!.memsize(codeGen.program.memsizer)
+                result += IRCodeChunk(null, null).also {
+                    addInstr(result, IRInstruction(Opcode.LOADM, vmDt, reg1 = resultRegister, labelSymbol = identifier.name), null)
+                    if (eltSize > 1) {
+                        it += codeGen.multiplyByConst(DataType.UWORD, indexWordReg, eltSize)
+                    }
+                    it += IRInstruction(Opcode.ADDR, IRDataType.WORD, reg1 = resultRegister, reg2 = indexWordReg)
+                }
             } else {
-                val eltSize = codeGen.program.memsizer.memorySize(expr.identifier.type, 1)
+                // regular array indexing
+                val eltSize = codeGen.program.memsizer.memorySize(identifier.type, 1)
                 result += IRCodeChunk(null, null).also {
                     loadAddressOfArrayLabel(resultRegister)
-                    if(eltSize>1 && !expr.identifier.type.isSplitWordArray) {
-                        it += IRInstruction(Opcode.MUL, IRDataType.WORD, reg1=indexWordReg, immediate = eltSize)
+                    if (eltSize > 1 && !identifier.type.isSplitWordArray) {
+                        it += codeGen.multiplyByConst(DataType.UWORD, indexWordReg, eltSize)
                     }
-                    it += IRInstruction(Opcode.ADDR, IRDataType.WORD, reg1=resultRegister, reg2=indexWordReg)
+                    it += IRInstruction(Opcode.ADDR, IRDataType.WORD, reg1 = resultRegister, reg2 = indexWordReg)
                 }
             }
-        } else {
+            return ExpressionCodeResult(result, vmDt, resultRegister, -1)
+        } else if(expr.identifier!=null ) {
+            val resultRegister = codeGen.registers.next(vmDt)
             loadAddressOfArrayLabel(resultRegister)
+            return ExpressionCodeResult(result, vmDt, resultRegister, -1)
+        } else {
+            require(vmDt==IRDataType.WORD)
+            val pointerTr = translateExpression(expr.dereference!!.startpointer)
+            result += pointerTr.chunks
+            val (instructions, offset) = traverseRestOfDerefChainToCalculateFinalAddress(expr.dereference!!, pointerTr.resultReg)
+            result += instructions
+            addInstr(result, IRInstruction(Opcode.ADD, IRDataType.WORD, reg1 = pointerTr.resultReg, immediate = offset.toInt()), null)
+            return ExpressionCodeResult(result, vmDt, pointerTr.resultReg, -1)
         }
-        return ExpressionCodeResult(result, vmDt, resultRegister, -1)
     }
 
     private fun translate(mem: PtMemoryByte): ExpressionCodeResult {
@@ -219,31 +339,32 @@ internal class ExpressionGen(private val codeGen: IRCodeGen) {
         }
 
         val ptrWithOffset = mem.address as? PtBinaryExpression
-        if(ptrWithOffset!=null && ptrWithOffset.operator=="+" && ptrWithOffset.left is PtIdentifier) {
-            if((ptrWithOffset.right as? PtNumber)?.number?.toInt() in 0..255) {
-                // LOADIX only works with byte index.
-                val ptrName = (ptrWithOffset.left as PtIdentifier).name
-                val offsetReg = codeGen.registers.next(IRDataType.BYTE)
-                result += IRCodeChunk(null, null).also {
-                    it += IRInstruction(Opcode.LOAD, IRDataType.BYTE, reg1=offsetReg, immediate = ptrWithOffset.right.asConstInteger())
-                    it += IRInstruction(Opcode.LOADIX, IRDataType.BYTE, reg1=resultRegister, reg2=offsetReg, labelSymbol = ptrName)
+        if(ptrWithOffset!=null) {
+            if(ptrWithOffset.operator=="+" && ptrWithOffset.left is PtIdentifier) {
+                val constOffset = (ptrWithOffset.right as? PtNumber)?.number?.toInt()
+                if(constOffset in 0..255) {
+                    val ptrName = (ptrWithOffset.left as PtIdentifier).name
+                    val pointerReg = codeGen.registers.next(IRDataType.WORD)
+                    result += IRCodeChunk(null, null).also {
+                        it += IRInstruction(Opcode.LOADM, IRDataType.WORD, reg1 = pointerReg, labelSymbol = ptrName)
+                        it += IRInstruction(Opcode.LOADFIELD, IRDataType.BYTE, reg1=resultRegister, reg2=pointerReg,  immediate = constOffset)
+                    }
+                    return ExpressionCodeResult(result, IRDataType.BYTE, resultRegister, -1)
                 }
+            }
+            val offsetTypecast = ptrWithOffset.right as? PtTypeCast
+            if(ptrWithOffset.operator=="+" && ptrWithOffset.left is PtIdentifier && (ptrWithOffset.right.type.isByte || offsetTypecast?.value?.type?.isByte==true)) {
+                // LOADIX only works with byte index.
+                val tr = if(offsetTypecast?.value?.type?.isByte==true)
+                    translateExpression(offsetTypecast.value)
+                else
+                    translateExpression(ptrWithOffset.right)
+                addToResult(result, tr, tr.resultReg, -1)
+                val ptrName = (ptrWithOffset.left as PtIdentifier).name
+                addInstr(result, IRInstruction(Opcode.LOADIX, IRDataType.BYTE, reg1=resultRegister, reg2=tr.resultReg, labelSymbol = ptrName), null)
                 return ExpressionCodeResult(result, IRDataType.BYTE, resultRegister, -1)
             }
         }
-        val offsetTypecast = ptrWithOffset?.right as? PtTypeCast
-        if(ptrWithOffset!=null && ptrWithOffset.operator=="+" && ptrWithOffset.left is PtIdentifier
-            && (ptrWithOffset.right.type.isByte || offsetTypecast?.value?.type?.isByte==true)) {
-            // LOADIX only works with byte index.
-            val tr = if(offsetTypecast?.value?.type?.isByte==true)
-                translateExpression(offsetTypecast.value)
-            else
-                translateExpression(ptrWithOffset.right)
-            addToResult(result, tr, tr.resultReg, -1)
-            val ptrName = (ptrWithOffset.left as PtIdentifier).name
-            addInstr(result, IRInstruction(Opcode.LOADIX, IRDataType.BYTE, reg1=resultRegister, reg2=tr.resultReg, labelSymbol = ptrName), null)
-            return ExpressionCodeResult(result, IRDataType.BYTE, resultRegister, -1)
-        }
 
         val tr = translateExpression(mem.address)
         addToResult(result, tr, tr.resultReg, -1)
@@ -289,7 +410,6 @@ internal class ExpressionGen(private val codeGen: IRCodeGen) {
         val haystackVar = check.haystackHeapVar!!
         when {
             haystackVar.type.isString -> {
-                addInstr(result, IRInstruction(Opcode.PREPARECALL, immediate = 2), null)
                 val elementTr = translateExpression(check.needle)
                 addToResult(result, elementTr, elementTr.resultReg, -1)
                 val iterableTr = translateExpression(haystackVar)
@@ -300,7 +420,6 @@ internal class ExpressionGen(private val codeGen: IRCodeGen) {
                 return ExpressionCodeResult(result, IRDataType.BYTE, resultReg, -1)
             }
             haystackVar.type.isByteArray -> {
-                addInstr(result, IRInstruction(Opcode.PREPARECALL, immediate = 3), null)
                 val elementTr = translateExpression(check.needle)
                 addToResult(result, elementTr, elementTr.resultReg, -1)
                 val iterableTr = translateExpression(haystackVar)
@@ -314,7 +433,6 @@ internal class ExpressionGen(private val codeGen: IRCodeGen) {
                 return ExpressionCodeResult(result, IRDataType.BYTE, resultReg, -1)
             }
             haystackVar.type.isWordArray -> {
-                addInstr(result, IRInstruction(Opcode.PREPARECALL, immediate = 3), null)
                 val elementTr = translateExpression(check.needle)
                 addToResult(result, elementTr, elementTr.resultReg, -1)
                 val iterableTr = translateExpression(haystackVar)
@@ -328,7 +446,6 @@ internal class ExpressionGen(private val codeGen: IRCodeGen) {
                 return ExpressionCodeResult(result, IRDataType.BYTE, resultReg, -1)
             }
             haystackVar.type.isFloatArray -> {
-                addInstr(result, IRInstruction(Opcode.PREPARECALL, immediate = 3), null)
                 val elementTr = translateExpression(check.needle)
                 addToResult(result, elementTr, -1, elementTr.resultFpReg)
                 val iterableTr = translateExpression(haystackVar)
@@ -346,11 +463,30 @@ internal class ExpressionGen(private val codeGen: IRCodeGen) {
     }
 
     private fun translate(arrayIx: PtArrayIndexer): ExpressionCodeResult {
+        if(arrayIx.type.isStructInstance)
+            throw AssemblyError("cannot translate POINTER[x] resulting in a struct instance; this is likely part of a larger expression POINTER[x].field and that has to be translated earlier as a whole")
+
         val eltSize = codeGen.program.memsizer.memorySize(arrayIx.type, null)
         val vmDt = irType(arrayIx.type)
         val result = mutableListOf<IRCodeChunkBase>()
-        val arrayVarSymbol = arrayIx.variable.name
+        val arrayVar = arrayIx.variable
+        if(arrayVar==null) {
+            val pointerTr = translateExpression(arrayIx.pointerderef!!)
+            result += pointerTr.chunks
+            val pointerReg = pointerTr.resultReg
+            return translatePointerIndexing(result, pointerReg, arrayIx.index, eltSize, vmDt)
+        }
+        if(arrayVar.type.isPointer) {
+            val pointerTr = translateExpression(arrayVar)
+            result += pointerTr.chunks
+            val pointerReg = pointerTr.resultReg
+            return translatePointerIndexing(result, pointerReg, arrayIx.index, eltSize, vmDt)
+        }
+
+        require(!arrayVar.type.isPointer) { "only regular array indexing here ${arrayIx.position}" }
         var resultRegister = -1
+        var resultFpRegister = -1
+        val arrayVarSymbol = arrayVar.name
 
         if(arrayIx.splitWords) {
             require(vmDt==IRDataType.WORD)
@@ -377,9 +513,8 @@ internal class ExpressionGen(private val codeGen: IRCodeGen) {
             return ExpressionCodeResult(result, vmDt, finalResultReg, -1)
         }
 
-        var resultFpRegister = -1
-        if(arrayIx.index is PtNumber) {
-            val memOffset = ((arrayIx.index as PtNumber).number.toInt() * eltSize)
+        fun indexByNumber(index: Int) {
+            val memOffset = index * eltSize
             if(vmDt==IRDataType.FLOAT) {
                 resultFpRegister = codeGen.registers.next(IRDataType.FLOAT)
                 addInstr(result, IRInstruction(Opcode.LOADM, IRDataType.FLOAT, fpReg1=resultFpRegister, labelSymbol = arrayVarSymbol, symbolOffset = memOffset), null)
@@ -388,23 +523,61 @@ internal class ExpressionGen(private val codeGen: IRCodeGen) {
                 resultRegister = codeGen.registers.next(vmDt)
                 addInstr(result, IRInstruction(Opcode.LOADM, vmDt, reg1=resultRegister, labelSymbol = arrayVarSymbol, symbolOffset = memOffset), null)
             }
-        } else {
-            val tr = translateExpression(arrayIx.index)
-            addToResult(result, tr, tr.resultReg, -1)
-            if(eltSize>1)
-                result += codeGen.multiplyByConst(IRDataType.BYTE, tr.resultReg, eltSize)
+        }
+
+        fun indexByExpression() {
+            val (code, indexByteReg) = codeGen.loadIndexReg(arrayIx.index, eltSize, false, arrayIx.splitWords)
+            result += code
             if(vmDt==IRDataType.FLOAT) {
                 resultFpRegister = codeGen.registers.next(IRDataType.FLOAT)
-                addInstr(result, IRInstruction(Opcode.LOADX, IRDataType.FLOAT, fpReg1 = resultFpRegister, reg1=tr.resultReg, labelSymbol = arrayVarSymbol), null)
+                addInstr(result, IRInstruction(Opcode.LOADX, IRDataType.FLOAT, fpReg1 = resultFpRegister, reg1=indexByteReg, labelSymbol = arrayVarSymbol), null)
             }
             else {
                 resultRegister = codeGen.registers.next(vmDt)
-                addInstr(result, IRInstruction(Opcode.LOADX, vmDt, reg1=resultRegister, reg2=tr.resultReg, labelSymbol = arrayVarSymbol), null)
+                addInstr(result, IRInstruction(Opcode.LOADX, vmDt, reg1=resultRegister, reg2=indexByteReg, labelSymbol = arrayVarSymbol), null)
             }
         }
+
+        if(arrayIx.index is PtNumber)
+            indexByNumber((arrayIx.index as PtNumber).number.toInt())
+        else
+            indexByExpression()
         return ExpressionCodeResult(result, vmDt, resultRegister, resultFpRegister)
     }
 
+    private fun translatePointerIndexing(
+        result: MutableList<IRCodeChunkBase>,
+        pointerReg: Int,
+        index: PtExpression,
+        eltSize: Int,
+        resultDt: IRDataType
+    ): ExpressionCodeResult {
+        var resultRegister = -1
+        var resultFpRegister = -1
+
+        if(index is PtNumber) {
+            val memOffset = eltSize * index.number.toInt()
+            if(memOffset>0)
+                addInstr(result, IRInstruction(Opcode.ADD, IRDataType.WORD, reg1=pointerReg, immediate = memOffset), null)
+        }
+        else {
+            val (code, indexWordReg) = codeGen.loadIndexReg(index, eltSize, true, false)
+            result += code
+            addInstr(result, IRInstruction(Opcode.ADDR, IRDataType.WORD, reg1=pointerReg, reg2=indexWordReg), null)
+        }
+
+        if(resultDt==IRDataType.FLOAT) {
+            resultFpRegister = codeGen.registers.next(IRDataType.FLOAT)
+            addInstr(result, IRInstruction(Opcode.LOADI, IRDataType.FLOAT, fpReg1=resultFpRegister, reg1=pointerReg), null)
+        }
+        else {
+            resultRegister = codeGen.registers.next(resultDt)
+            addInstr(result, IRInstruction(Opcode.LOADI, resultDt, reg1=resultRegister, reg2=pointerReg), null)
+        }
+
+        return ExpressionCodeResult(result, resultDt, resultRegister, resultFpRegister)
+    }
+
     private fun translate(expr: PtPrefix): ExpressionCodeResult {
         val result = mutableListOf<IRCodeChunkBase>()
         val tr = translateExpression(expr.value)
@@ -445,9 +618,9 @@ internal class ExpressionGen(private val codeGen: IRCodeGen) {
                         addInstr(result, IRInstruction(Opcode.CMPI, IRDataType.BYTE, reg1=tr.resultReg, immediate = 0), null)
                         actualResultReg2 = loadStatusAsBooleanResult(Opcode.BSTNE, result)
                     }
-                    valueDt.isWord -> {
+                    valueDt.isWord || valueDt.isPointer -> {
                         addInstr(result, IRInstruction(Opcode.CMPI, IRDataType.WORD, reg1=tr.resultReg, immediate = 0), null)
-                        actualResultReg2 =loadStatusAsBooleanResult(Opcode.BSTNE, result)
+                        actualResultReg2 = loadStatusAsBooleanResult(Opcode.BSTNE, result)
                     }
                     valueDt.isFloat -> {
                         actualResultReg2 = codeGen.registers.next(IRDataType.BYTE)
@@ -456,7 +629,7 @@ internal class ExpressionGen(private val codeGen: IRCodeGen) {
                             it += IRInstruction(Opcode.AND, IRDataType.BYTE, reg1=actualResultReg2, immediate = 1)
                         }
                     }
-                    else -> throw AssemblyError("weird cast value type")
+                    else -> throw AssemblyError("weird cast value type ${cast.position}")
                 }
             }
             BaseDataType.UBYTE -> {
@@ -472,7 +645,7 @@ internal class ExpressionGen(private val codeGen: IRCodeGen) {
                         actualResultReg2 = codeGen.registers.next(IRDataType.BYTE)
                         addInstr(result, IRInstruction(Opcode.FTOUB, IRDataType.FLOAT, reg1=actualResultReg2, fpReg1 = tr.resultFpReg), null)
                     }
-                    else -> throw AssemblyError("weird cast value type")
+                    else -> throw AssemblyError("weird cast value type ${cast.position}")
                 }
             }
             BaseDataType.BYTE -> {
@@ -488,7 +661,7 @@ internal class ExpressionGen(private val codeGen: IRCodeGen) {
                         actualResultReg2 = codeGen.registers.next(IRDataType.BYTE)
                         addInstr(result, IRInstruction(Opcode.FTOSB, IRDataType.FLOAT, reg1=actualResultReg2, fpReg1 = tr.resultFpReg), null)
                     }
-                    else -> throw AssemblyError("weird cast value type")
+                    else -> throw AssemblyError("weird cast value type ${cast.position}")
                 }
             }
             BaseDataType.UWORD -> {
@@ -510,7 +683,10 @@ internal class ExpressionGen(private val codeGen: IRCodeGen) {
                         actualResultReg2 = codeGen.registers.next(IRDataType.WORD)
                         addInstr(result, IRInstruction(Opcode.FTOUW, IRDataType.FLOAT, reg1=actualResultReg2, fpReg1 = tr.resultFpReg), null)
                     }
-                    else -> throw AssemblyError("weird cast value type")
+                    BaseDataType.POINTER -> {
+                        actualResultReg2 = tr.resultReg
+                    }
+                    else -> throw AssemblyError("weird cast value type ${cast.position}")
                 }
             }
             BaseDataType.WORD -> {
@@ -532,7 +708,7 @@ internal class ExpressionGen(private val codeGen: IRCodeGen) {
                         actualResultReg2 = codeGen.registers.next(IRDataType.WORD)
                         addInstr(result, IRInstruction(Opcode.FTOSW, IRDataType.FLOAT, reg1=actualResultReg2, fpReg1 = tr.resultFpReg), null)
                     }
-                    else -> throw AssemblyError("weird cast value type")
+                    else -> throw AssemblyError("weird cast value type ${cast.position}")
                 }
             }
             BaseDataType.FLOAT -> {
@@ -550,49 +726,61 @@ internal class ExpressionGen(private val codeGen: IRCodeGen) {
                     BaseDataType.WORD -> {
                         addInstr(result, IRInstruction(Opcode.FFROMSW, IRDataType.FLOAT, reg1=tr.resultReg, fpReg1 = actualResultFpReg2), null)
                     }
-                    else -> throw AssemblyError("weird cast value type")
+                    else -> throw AssemblyError("weird cast value type ${cast.position}")
                 }
             }
-            else -> throw AssemblyError("weird cast type")
+            BaseDataType.POINTER -> {
+                require(valueDt.isUnsignedWord || valueDt.isPointer)
+                actualResultReg2 = tr.resultReg
+                // no further conversion required, pointers are all just uwords
+            }
+            BaseDataType.ARRAY_POINTER -> {
+                TODO("typecast to array of pointers $valueDt -> ${cast.type}")
+            }
+            else -> throw AssemblyError("weird cast value type ${cast.position}")
         }
 
         return ExpressionCodeResult(result, irType(cast.type), actualResultReg2, actualResultFpReg2)
     }
 
     private fun translate(binExpr: PtBinaryExpression): ExpressionCodeResult {
-        val vmDt = irType(binExpr.left.type)
         val signed = binExpr.left.type.isSigned
-        return when(binExpr.operator) {
-            "+" -> operatorPlus(binExpr, vmDt)
-            "-" -> operatorMinus(binExpr, vmDt)
-            "*" -> operatorMultiply(binExpr, vmDt)
-            "/" -> operatorDivide(binExpr, vmDt, signed)
-            "%" -> operatorModulo(binExpr, vmDt)
-            "|" -> operatorOr(binExpr, vmDt, true)
-            "&" -> operatorAnd(binExpr, vmDt, true)
-            "^", "xor" -> operatorXor(binExpr, vmDt)
-            "or" -> operatorOr(binExpr, vmDt, false)
-            "and" -> operatorAnd(binExpr, vmDt, false)
-            "<<" -> operatorShiftLeft(binExpr, vmDt)
-            ">>" -> operatorShiftRight(binExpr, vmDt, signed)
-            "==" -> operatorEquals(binExpr, vmDt, false)
-            "!=" -> operatorEquals(binExpr, vmDt, true)
-            "<" -> operatorLessThan(binExpr, vmDt, signed, false)
-            ">" -> operatorGreaterThan(binExpr, vmDt, signed, false)
-            "<=" -> operatorLessThan(binExpr, vmDt, signed, true)
-            ">=" -> operatorGreaterThan(binExpr, vmDt, signed, true)
-            else -> throw AssemblyError("weird operator ${binExpr.operator}")
+        if(binExpr.operator==".") {
+            return operatorDereference(binExpr)       // eww, nasty, would rather not have any such expressions anymore
+        } else {
+            val vmDt = irType(binExpr.left.type)
+            return when (binExpr.operator) {
+                "+" -> operatorPlus(binExpr, vmDt)
+                "-" -> operatorMinus(binExpr, vmDt)
+                "*" -> operatorMultiply(binExpr, binExpr.left.type)
+                "/" -> operatorDivide(binExpr, binExpr.left.type)
+                "%" -> operatorModulo(binExpr, vmDt)
+                "|" -> operatorOr(binExpr, vmDt, true)
+                "&" -> operatorAnd(binExpr, vmDt, true)
+                "^", "xor" -> operatorXor(binExpr, vmDt)
+                "or" -> operatorOr(binExpr, vmDt, false)
+                "and" -> operatorAnd(binExpr, vmDt, false)
+                "<<" -> operatorShiftLeft(binExpr, vmDt)
+                ">>" -> operatorShiftRight(binExpr, vmDt, signed)
+                "==" -> operatorEquals(binExpr, vmDt, false)
+                "!=" -> operatorEquals(binExpr, vmDt, true)
+                "<" -> operatorLessThan(binExpr, vmDt, signed, false)
+                ">" -> operatorGreaterThan(binExpr, vmDt, signed, false)
+                "<=" -> operatorLessThan(binExpr, vmDt, signed, true)
+                ">=" -> operatorGreaterThan(binExpr, vmDt, signed, true)
+                else -> throw AssemblyError("weird operator ${binExpr.operator}")
+            }
         }
     }
 
     internal fun translate(fcall: PtFunctionCall): ExpressionCodeResult {
         val callTarget = codeGen.symbolTable.lookup(fcall.name)!!
 
-        if(callTarget.scopedName in listOf("sys.push", "sys.pushw", "sys.pop", "sys.popw", "floats.push", "floats.pop")) {
+        if(callTarget.scopedNameString in listOf("sys.push", "sys.pushw", "sys.pop", "sys.popw", "floats.push", "floats.pop")) {
             // special case, these should be inlined, or even use specialized instructions. Instead of doing a normal subroutine call.
             return translateStackFunctions(fcall, callTarget)
         }
-        when(callTarget.scopedName) {
+        when(callTarget.scopedNameString) {
             "sys.clear_carry" -> {
                 val chunk = mutableListOf<IRCodeChunkBase>()
                 addInstr(chunk, IRInstruction(Opcode.CLC), null)
@@ -618,7 +806,6 @@ internal class ExpressionGen(private val codeGen: IRCodeGen) {
         when (callTarget) {
             is StSub -> {
                 val result = mutableListOf<IRCodeChunkBase>()
-                addInstr(result, IRInstruction(Opcode.PREPARECALL, immediate = callTarget.parameters.size), null)
                 // assign the arguments
                 val argRegisters = mutableListOf<FunctionCallArgs.ArgumentSpec>()
                 for ((arg, parameter) in fcall.args.zip(callTarget.parameters)) {
@@ -642,7 +829,7 @@ internal class ExpressionGen(private val codeGen: IRCodeGen) {
                     }
                 }
                 // return value(s)
-                // TODO: for current implemenation of the call convention in case of multiple return values,
+                // TODO: for current implementation of the call convention in case of multiple return values,
                 // a list of Ir virtual registers to hold the results is NOT correct (they're loaded into AY + R15..R0 instead!)
                 // So we use an empty list to avoid confusion here.   This may change in a future version.
                 val returnRegSpecs = if(fcall.void || callTarget.returns.size>1) emptyList() else {
@@ -670,7 +857,6 @@ internal class ExpressionGen(private val codeGen: IRCodeGen) {
             }
             is StExtSub -> {
                 val result = mutableListOf<IRCodeChunkBase>()
-                addInstr(result, IRInstruction(Opcode.PREPARECALL, immediate = callTarget.parameters.size), null)
                 // assign the arguments
                 val argRegisters = mutableListOf<FunctionCallArgs.ArgumentSpec>()
                 for ((arg, parameter) in fcall.args.zip(callTarget.parameters)) {
@@ -709,9 +895,21 @@ internal class ExpressionGen(private val codeGen: IRCodeGen) {
                                 Opcode.CALL,
                                 address = address.address.toInt(),
                                 fcallArgs = FunctionCallArgs(argRegisters, returnRegs))
-                        }
-                        else {
-                            TODO("callfar into another bank is not implemented for the selected compilation target")
+                        } else if(address.constbank!=null) {
+                            IRInstruction(
+                                Opcode.CALLFAR,
+                                address = address.address.toInt(),
+                                immediate = address.constbank!!.toInt()
+                            )
+                        } else {
+                            val tr = translateExpression(address.varbank!!)
+                            require(tr.dt==IRDataType.BYTE)
+                            result += tr.chunks
+                            IRInstruction(
+                                Opcode.CALLFARVB,
+                                address = address.address.toInt(),
+                                reg1 = tr.resultReg
+                            )
                         }
                     }
                 addInstr(result, call, null)
@@ -762,6 +960,9 @@ internal class ExpressionGen(private val codeGen: IRCodeGen) {
                 else
                     ExpressionCodeResult(result, returnRegSpec!!.dt, finalReturnRegister, -1)
             }
+            is StStruct -> {
+                throw AssemblyError("stray struct constructor should have been removed (normally it can only occur as initialization expression for a pointer variable)")
+            }
             else -> {
                 if(callTarget.type == StNodeType.LABEL) {
                     require(fcall.void)
@@ -771,7 +972,7 @@ internal class ExpressionGen(private val codeGen: IRCodeGen) {
                     return ExpressionCodeResult(result, IRDataType.BYTE, -1, -1)
                 }
                 else {
-                    throw AssemblyError("invalid node type")
+                    throw AssemblyError("invalid node type ${callTarget.type} at ${callTarget.astNode?.position}")
                 }
             }
         }
@@ -804,7 +1005,7 @@ internal class ExpressionGen(private val codeGen: IRCodeGen) {
 
     private fun translateStackFunctions(fcall: PtFunctionCall, callTarget: StNode): ExpressionCodeResult {
         val chunk = mutableListOf<IRCodeChunkBase>()
-        when(callTarget.scopedName) {
+        when(callTarget.scopedNameString) {
             "sys.push" -> {
                 // push byte
                 val tr = translateExpression(fcall.args.single())
@@ -1039,7 +1240,7 @@ internal class ExpressionGen(private val codeGen: IRCodeGen) {
     }
 
     private fun loadStatusAsBooleanResult(branchForTrue: Opcode, result: MutableList<IRCodeChunkBase>): Int {
-        // TODO this used to be a single instruction like SCC, SCS, SZ etc but those were problematic
+        // TODO this used to be a single instruction like SCC, SCS, SZ etc
         val other = codeGen.createLabelName()
         val after = codeGen.createLabelName()
         val resultReg = codeGen.registers.next(IRDataType.BYTE)
@@ -1054,7 +1255,7 @@ internal class ExpressionGen(private val codeGen: IRCodeGen) {
     }
 
     private fun compareRegisterAsBooleanResult(branchForTrue: Opcode, dt: IRDataType, reg1: Int, reg2: Int, result: MutableList<IRCodeChunkBase>): Int {
-        // TODO this used to be a single instruction like SCC, SCS, SZ etc but those were problematic
+        // TODO this used to be a single instruction like SCC, SCS, SZ etc
         val other = codeGen.createLabelName()
         val after = codeGen.createLabelName()
         val resultReg = codeGen.registers.next(IRDataType.BYTE)
@@ -1214,7 +1415,8 @@ internal class ExpressionGen(private val codeGen: IRCodeGen) {
         }
     }
 
-    private fun operatorDivide(binExpr: PtBinaryExpression, vmDt: IRDataType, signed: Boolean): ExpressionCodeResult {
+    private fun operatorDivide(binExpr: PtBinaryExpression, dt: DataType): ExpressionCodeResult {
+        val vmDt = irType(dt)
         val result = mutableListOf<IRCodeChunkBase>()
         val constFactorRight = binExpr.right as? PtNumber
         if(vmDt==IRDataType.FLOAT) {
@@ -1229,11 +1431,11 @@ internal class ExpressionGen(private val codeGen: IRCodeGen) {
                 addToResult(result, leftTr, -1, leftTr.resultFpReg)
                 val rightTr = translateExpression(binExpr.right)
                 addToResult(result, rightTr, -1, rightTr.resultFpReg)
-                addInstr(result, if(signed)
-                        IRInstruction(Opcode.DIVSR, vmDt, fpReg1 = leftTr.resultFpReg, fpReg2=rightTr.resultFpReg)
-                    else
-                        IRInstruction(Opcode.DIVR, vmDt, fpReg1 = leftTr.resultFpReg, fpReg2=rightTr.resultFpReg)
-                        , null)
+                addInstr(result, if(dt.isSigned)
+                    IRInstruction(Opcode.DIVSR, vmDt, fpReg1 = leftTr.resultFpReg, fpReg2=rightTr.resultFpReg)
+                else
+                    IRInstruction(Opcode.DIVR, vmDt, fpReg1 = leftTr.resultFpReg, fpReg2=rightTr.resultFpReg)
+                    , null)
                 return ExpressionCodeResult(result, vmDt, -1, leftTr.resultFpReg)
             }
         } else {
@@ -1241,35 +1443,36 @@ internal class ExpressionGen(private val codeGen: IRCodeGen) {
                 val tr = translateExpression(binExpr.left)
                 addToResult(result, tr, tr.resultReg, -1)
                 val factor = constFactorRight.number.toInt()
-                result += codeGen.divideByConst(vmDt, tr.resultReg, factor, signed)
+                result += codeGen.divideByConst(vmDt, tr.resultReg, factor, dt.isSigned)
                 ExpressionCodeResult(result, vmDt, tr.resultReg, -1)
             } else {
                 if(binExpr.right is PtNumber) {
                     val leftTr = translateExpression(binExpr.left)
                     addToResult(result, leftTr, leftTr.resultReg, -1)
-                    addInstr(result, if (signed)
-                            IRInstruction(Opcode.DIVS, vmDt, reg1 = leftTr.resultReg, immediate = (binExpr.right as PtNumber).number.toInt())
-                        else
-                            IRInstruction(Opcode.DIV, vmDt, reg1 = leftTr.resultReg, immediate = (binExpr.right as PtNumber).number.toInt())
-                            , null)
+                    addInstr(result, if (dt.isSigned)
+                        IRInstruction(Opcode.DIVS, vmDt, reg1 = leftTr.resultReg, immediate = (binExpr.right as PtNumber).number.toInt())
+                    else
+                        IRInstruction(Opcode.DIV, vmDt, reg1 = leftTr.resultReg, immediate = (binExpr.right as PtNumber).number.toInt())
+                        , null)
                     ExpressionCodeResult(result, vmDt, leftTr.resultReg, -1)
                 } else {
                     val leftTr = translateExpression(binExpr.left)
                     addToResult(result, leftTr, leftTr.resultReg, -1)
                     val rightTr = translateExpression(binExpr.right)
                     addToResult(result, rightTr, rightTr.resultReg, -1)
-                    addInstr(result, if (signed)
-                            IRInstruction(Opcode.DIVSR, vmDt, reg1 = leftTr.resultReg, reg2 = rightTr.resultReg)
-                        else
-                            IRInstruction(Opcode.DIVR, vmDt, reg1 = leftTr.resultReg, reg2 = rightTr.resultReg)
-                            , null)
+                    addInstr(result, if (dt.isSigned)
+                        IRInstruction(Opcode.DIVSR, vmDt, reg1 = leftTr.resultReg, reg2 = rightTr.resultReg)
+                    else
+                        IRInstruction(Opcode.DIVR, vmDt, reg1 = leftTr.resultReg, reg2 = rightTr.resultReg)
+                        , null)
                     ExpressionCodeResult(result, vmDt, leftTr.resultReg, -1)
                 }
             }
         }
     }
 
-    private fun operatorMultiply(binExpr: PtBinaryExpression, vmDt: IRDataType): ExpressionCodeResult {
+    private fun operatorMultiply(binExpr: PtBinaryExpression, dt: DataType): ExpressionCodeResult {
+        val vmDt = irType(dt)
         val result = mutableListOf<IRCodeChunkBase>()
         val constFactorLeft = binExpr.left as? PtNumber
         val constFactorRight = binExpr.right as? PtNumber
@@ -1291,7 +1494,7 @@ internal class ExpressionGen(private val codeGen: IRCodeGen) {
                 addToResult(result, leftTr, -1, leftTr.resultFpReg)
                 val rightTr = translateExpression(binExpr.right)
                 addToResult(result, rightTr, -1, rightTr.resultFpReg)
-                addInstr(result, IRInstruction(Opcode.MULR, vmDt, fpReg1 = leftTr.resultFpReg, fpReg2 = rightTr.resultFpReg), null)
+                addInstr(result, IRInstruction(Opcode.MULSR, vmDt, fpReg1 = leftTr.resultFpReg, fpReg2 = rightTr.resultFpReg), null)
                 ExpressionCodeResult(result, vmDt, -1, leftTr.resultFpReg)
             }
         } else {
@@ -1299,20 +1502,21 @@ internal class ExpressionGen(private val codeGen: IRCodeGen) {
                 val tr = translateExpression(binExpr.right)
                 addToResult(result, tr, tr.resultReg, -1)
                 val factor = constFactorLeft.number.toInt()
-                result += codeGen.multiplyByConst(vmDt, tr.resultReg, factor)
+                result += codeGen.multiplyByConst(dt, tr.resultReg, factor)
                 ExpressionCodeResult(result, vmDt, tr.resultReg, -1)
             } else if(constFactorRight!=null && !constFactorRight.type.isFloat) {
                 val tr = translateExpression(binExpr.left)
                 addToResult(result, tr, tr.resultReg, -1)
                 val factor = constFactorRight.number.toInt()
-                result += codeGen.multiplyByConst(vmDt, tr.resultReg, factor)
+                result += codeGen.multiplyByConst(dt, tr.resultReg, factor)
                 ExpressionCodeResult(result, vmDt, tr.resultReg, -1)
             } else {
                 val leftTr = translateExpression(binExpr.left)
                 addToResult(result, leftTr, leftTr.resultReg, -1)
                 val rightTr = translateExpression(binExpr.right)
                 addToResult(result, rightTr, rightTr.resultReg, -1)
-                addInstr(result, IRInstruction(Opcode.MULR, vmDt, reg1 = leftTr.resultReg, reg2 = rightTr.resultReg), null)
+                val opcode = if(dt.isSigned) Opcode.MULSR else Opcode.MULR
+                addInstr(result, IRInstruction(opcode, vmDt, reg1 = leftTr.resultReg, reg2 = rightTr.resultReg), null)
                 ExpressionCodeResult(result, vmDt, leftTr.resultReg, -1)
             }
         }
@@ -1428,6 +1632,117 @@ internal class ExpressionGen(private val codeGen: IRCodeGen) {
         }
     }
 
+    private fun operatorDereference(binExpr: PtBinaryExpression): ExpressionCodeResult {
+        // the only case we support here is:   a.b.c[i] . value
+        val left = binExpr.left as? PtArrayIndexer
+        val right = binExpr.right as? PtIdentifier
+        require(binExpr.operator=="." && left!=null && right!=null) {"invalid dereference expression ${binExpr.position}"}
+        val result = mutableListOf<IRCodeChunkBase>()
+        val field: Pair<DataType, UInt>
+        val pointerReg: Int
+        var extraFieldOffset = 0
+
+        if(left.type.isStructInstance) {
+
+            // indexing on a pointer directly
+            // fetch pointer address, determine struct and field, add index * structsize
+            if(left.variable!=null) {
+                val pointerTr = translateExpression(left.variable!!)
+                result += pointerTr.chunks
+                pointerReg = pointerTr.resultReg
+            } else if(left.pointerderef!=null) {
+                TODO("get pointer from deref $left")
+            } else {
+                throw AssemblyError("weird arrayindexer $left")
+            }
+            val struct = left.type.subType!! as StStruct
+            val constindex = left.index as? PtNumber
+            if(constindex!=null) {
+                extraFieldOffset = struct.size.toInt() * constindex.number.toInt()
+            } else {
+                val (chunks, indexReg) = codeGen.loadIndexReg(left.index, struct.size.toInt(), true, false)
+                result += chunks
+                addInstr(result, IRInstruction(Opcode.ADDR, IRDataType.WORD, reg1 = pointerReg, reg2 = indexReg), null)
+            }
+            field = struct.getField(right.name, codeGen.program.memsizer)
+
+        } else {
+
+            // indexing on an array with pointers
+            // fetch the pointer from the array, determine the struct & field
+            val indexedTr = translateExpression(left)
+            result += indexedTr.chunks
+            pointerReg = indexedTr.resultReg
+            val struct = left.type.dereference().subType as? StStruct
+            require(indexedTr.dt == IRDataType.WORD && struct != null)
+            field = struct.getField(right.name, codeGen.program.memsizer)
+        }
+
+        // add field offset to pointer and load the value into the result register
+        val fieldVmDt = irType(field.first)
+        var resultFpReg = -1
+        var resultReg = -1
+        if (fieldVmDt == IRDataType.FLOAT)
+            resultFpReg = codeGen.registers.next(IRDataType.FLOAT)
+        else
+            resultReg = codeGen.registers.next(fieldVmDt)
+        result += IRCodeChunk(null, null).also {
+            it += IRInstruction(Opcode.ADD, IRDataType.WORD, reg1 = pointerReg, immediate = field.second.toInt() + extraFieldOffset)
+            it += if (fieldVmDt == IRDataType.FLOAT)
+                IRInstruction(Opcode.LOADI, IRDataType.FLOAT, fpReg1 = resultFpReg, reg1 = pointerReg)
+            else
+                IRInstruction(Opcode.LOADI, fieldVmDt, reg1 = resultReg, reg2 = pointerReg)
+        }
+        return ExpressionCodeResult(result, fieldVmDt, resultReg, resultFpReg)
+    }
+
+    internal fun traverseRestOfDerefChainToCalculateFinalAddress(targetPointerDeref: PtPointerDeref, pointerReg: Int): Pair<IRCodeChunks, UInt> {
+        // returns instructions to calculate the pointer address, and the offset into the struct it points to
+        // so that LOADFIELD and STOREFIELD opcodes can be used instead of having an explicit extra ADD
+
+        val result = mutableListOf<IRCodeChunkBase>()
+
+        if(targetPointerDeref.chain.isEmpty())
+            return result to 0u   // nothing to do; there's no deref chain
+
+        var struct: StStruct? = null
+        if(targetPointerDeref.startpointer.type.subType!=null)
+            struct = targetPointerDeref.startpointer.type.subType as StStruct
+        if(targetPointerDeref.chain.isNotEmpty()) {
+            // traverse deref chain
+            for(deref in targetPointerDeref.chain.dropLast(1)) {
+                val fieldinfo = struct!!.getField(deref, codeGen.program.memsizer)
+                struct = fieldinfo.first.subType as StStruct
+                // get new pointer from field
+                result += IRCodeChunk(null, null).also {
+                    it += IRInstruction(Opcode.ADD, IRDataType.WORD, reg1 = pointerReg, immediate = fieldinfo.second.toInt())
+                    // LOADI has an exception to allow reg1 and reg2 to be the same, so we can avoid using extra temporary registers and LOADS
+                    it += IRInstruction(Opcode.LOADI, IRDataType.WORD, reg1 = pointerReg, reg2 = pointerReg)
+                }
+            }
+        }
+
+        val field = targetPointerDeref.chain.last()
+        val fieldinfo = struct!!.getField(field, codeGen.program.memsizer)
+        if(fieldinfo.second>0u) {
+            if(targetPointerDeref.derefLast) {
+                require(fieldinfo.first.isPointer)
+                // add the field offset
+                addInstr(result, IRInstruction(Opcode.ADD, IRDataType.WORD, reg1 = pointerReg, immediate = fieldinfo.second.toInt()), null)
+                // LOADI has an exception to allow reg1 and reg2 to be the same, so we can avoid using extra temporary registers and LOADS
+                addInstr(result, IRInstruction(Opcode.LOADI, IRDataType.WORD, reg1 = pointerReg, reg2 = pointerReg), null)
+                return result to 0u
+            } else {
+                return result to fieldinfo.second
+            }
+        }
+        if(targetPointerDeref.derefLast) {
+            require(fieldinfo.first.isPointer)
+            // LOADI has an exception to allow reg1 and reg2 to be the same, so we can avoid using extra temporary registers and LOADS
+            addInstr(result, IRInstruction(Opcode.LOADI, IRDataType.WORD, reg1 = pointerReg, reg2 = pointerReg), null)
+        }
+        return result to 0u
+    }
 }
 
 

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

@@ -48,6 +48,7 @@ class IRCodeGen(
         irProg.linkChunks()
         irProg.convertAsmChunks()
 
+        // the optimizer also does 1 essential step regardless of optimizations: joining adjacent chunks.
         val optimizer = IRPeepholeOptimizer(irProg)
         optimizer.optimize(options.optimize, errors)
         irProg.validate()
@@ -55,6 +56,8 @@ class IRCodeGen(
         return irProg
     }
 
+    fun registerTypes(): Map<Int, IRDataType> = registers.getTypes()
+
     private fun changeGlobalVarInits(symbolTable: SymbolTable) {
         // Normally, block level (global) variables that have a numeric initialization value
         // are initialized via an assignment statement.
@@ -64,15 +67,16 @@ class IRCodeGen(
             if(variable.uninitialized && variable.parent.type==StNodeType.BLOCK) {
                 val block = variable.parent.astNode as PtBlock
                 val initialization = (block.children.firstOrNull {
-                    it is PtAssignment && it.target.identifier?.name==variable.scopedName
+                    it is PtAssignment && it.isVarInitializer && it.target.identifier?.name==variable.scopedNameString
                 } as PtAssignment?)
-                val initValue = initialization?.value
-                when(initValue){
+                when(val initValue = initialization?.value){
                     is PtBool -> {
+                        require(initValue.asInt()!=0 || variable.zpwish!=ZeropageWish.NOT_IN_ZEROPAGE) { "non-zp variable should not be initialized with 0, it will already be zeroed as part of BSS clear, initializer=$initialization" }
                         variable.setOnetimeInitNumeric(initValue.asInt().toDouble())
                         initsToRemove += block to initialization
                     }
                     is PtNumber -> {
+                        require(initValue.number!=0.0 || variable.zpwish!=ZeropageWish.NOT_IN_ZEROPAGE) { "non-zp variable should not be initialized with 0, it will already be zeroed as part of BSS clear, initializer=$initialization" }
                         variable.setOnetimeInitNumeric(initValue.number)
                         initsToRemove += block to initialization
                     }
@@ -101,6 +105,15 @@ class IRCodeGen(
                 is PtVariable -> require('.' in node.name) { "node $node name is not scoped: ${node.name}" }
                 is PtProgram -> require('.' !in node.name) { "program name should not be scoped: ${node.name}" }
                 is PtSubroutineParameter -> require('.' in node.name) { "node $node name is not scoped: ${node.name}" }
+                is PtPointerDeref -> require('.' in node.startpointer.name) { "node $node name is not scoped: ${node.startpointer.name}" }
+                is PtIdentifier -> {
+                    if('.' !in node.name) {
+                        // there is 1 case where the identifier is not scoped: if it's the value field name after a pointer array indexing.
+                        val expr = node.parent as? PtBinaryExpression
+                        if (expr?.operator != "." || expr.right !== node || expr.left !is PtArrayIndexer || (!expr.left.type.isPointer && !expr.left.type.isStructInstance))
+                            require('.' in node.name) { "node $node name is not scoped: ${node.name}" }
+                    }
+                }
                 else -> { /* node has no name or is ok to have no dots in the name */ }
             }
             node.children.forEach { verifyPtNode(it) }
@@ -194,10 +207,7 @@ class IRCodeGen(
                 old.fpReg1,
                 old.fpReg2,
                 immediate = immediateValue,
-                null,
-                address = addressValue,
-                null,
-                null
+                address = addressValue
             )
         }
     }
@@ -256,9 +266,11 @@ class IRCodeGen(
             is PtBool,
             is PtArray,
             is PtBlock,
-            is PtDefer -> throw AssemblyError("should have been transformed")
-            is PtString -> throw AssemblyError("should not occur as separate statement node ${node.position}")
-            is PtSub -> throw AssemblyError("nested subroutines should have been flattened ${node.position}")
+            is PtDefer -> throw AssemblyError("defer should have been transformed")
+            is PtString -> throw AssemblyError("string should not occur as separate statement node $node")
+            is PtSub -> throw AssemblyError("nested subroutines should have been flattened $node")
+            is PtStructDecl -> emptyList()
+            is PtSubSignature -> emptyList()
             else -> TODO("missing codegen for $node")
         }
 
@@ -420,35 +432,44 @@ class IRCodeGen(
         whenStmt.choices.children.forEach {
             val choice = it as PtWhenChoice
             if(choice.isElse) {
+                require(choice.parent.children.last() === choice)
                 result += translateNode(choice.statements)
-                addInstr(result, IRInstruction(Opcode.JUMP, labelSymbol = endLabel), null)
+                // is always the last node so can fall through
             } else {
                 if(choice.statements.children.isEmpty()) {
                     // no statements for this choice value, jump to the end immediately
-                    choice.values.children.map { it as PtNumber }.sortedBy { it.number }.forEach { value ->
-                        result += IRCodeChunk(null, null).also {
-                            it += IRInstruction(Opcode.CMPI, valueDt, reg1=valueTr.resultReg, immediate = value.number.toInt())
-                            it += IRInstruction(Opcode.BSTEQ, labelSymbol = endLabel)
+                    choice.values.children.map { v -> v as PtNumber }.sortedBy { v -> v.number }.forEach { value ->
+                        result += IRCodeChunk(null, null).also { chunk ->
+                            chunk += IRInstruction(Opcode.CMPI, valueDt, reg1=valueTr.resultReg, immediate = value.number.toInt())
+                            chunk += IRInstruction(Opcode.BSTEQ, labelSymbol = endLabel)
                         }
                     }
                 } else {
                     val choiceLabel = createLabelName()
-                    choices.add(choiceLabel to choice)
-                    choice.values.children.map { it as PtNumber }.sortedBy { it.number }.forEach { value ->
-                        result += IRCodeChunk(null, null).also {
-                            it += IRInstruction(Opcode.CMPI, valueDt, reg1=valueTr.resultReg, immediate = value.number.toInt())
-                            it += IRInstruction(Opcode.BSTEQ, labelSymbol = choiceLabel)
+                    val onlyJumpLabel = ((choice.statements.children.singleOrNull() as? PtJump)?.target as? PtIdentifier)?.name
+                    val branchLabel: String
+                    if(onlyJumpLabel==null) {
+                        choices.add(choiceLabel to choice)
+                        branchLabel = choiceLabel
+                    } else {
+                        branchLabel = onlyJumpLabel
+                    }
+                    choice.values.children.map { v -> v as PtNumber }.sortedBy { v -> v.number }.forEach { value ->
+                        result += IRCodeChunk(null, null).also { chunk ->
+                            chunk += IRInstruction(Opcode.CMPI, valueDt, reg1=valueTr.resultReg, immediate = value.number.toInt())
+                            chunk += IRInstruction(Opcode.BSTEQ, labelSymbol = branchLabel)
                         }
                     }
                 }
             }
         }
-        addInstr(result, IRInstruction(Opcode.JUMP, labelSymbol = endLabel), null)
+
+        if(choices.isNotEmpty())
+            addInstr(result, IRInstruction(Opcode.JUMP, labelSymbol = endLabel), null)
 
         choices.forEach { (label, choice) ->
             result += labelFirstChunk(translateNode(choice.statements), label)
-            val lastStatement = choice.statements.children.last()
-            if(lastStatement !is PtReturn && lastStatement !is PtJump)
+            if(!choice.isOnlyGotoOrReturn())
                 addInstr(result, IRInstruction(Opcode.JUMP, labelSymbol = endLabel), null)
         }
 
@@ -468,11 +489,12 @@ class IRCodeGen(
                     translateForInNonConstantRange(forLoop, loopvar)
             }
             is PtIdentifier -> {
-                require(forLoop.variable.name == loopvar.scopedName)
+                require(forLoop.variable.name == loopvar.scopedNameString)
+                val elementDt = irType(iterable.type.elementType())
                 val iterableLength = symbolTable.getLength(iterable.name)
                 val loopvarSymbol = forLoop.variable.name
                 val indexReg = registers.next(IRDataType.BYTE)
-                val tmpReg = registers.next(IRDataType.BYTE)
+                val tmpReg = registers.next(elementDt)
                 val loopLabel = createLabelName()
                 val endLabel = createLabelName()
                 when {
@@ -480,9 +502,9 @@ class IRCodeGen(
                         // iterate over a zero-terminated string
                         addInstr(result, IRInstruction(Opcode.LOAD, IRDataType.BYTE, reg1 = indexReg, immediate = 0), null)
                         result += IRCodeChunk(loopLabel, null).also {
-                            it += IRInstruction(Opcode.LOADX, IRDataType.BYTE, reg1 = tmpReg, reg2 = indexReg, labelSymbol = iterable.name)
+                            it += IRInstruction(Opcode.LOADX, elementDt, reg1 = tmpReg, reg2 = indexReg, labelSymbol = iterable.name)
                             it += IRInstruction(Opcode.BSTEQ, labelSymbol = endLabel)
-                            it += IRInstruction(Opcode.STOREM, IRDataType.BYTE, reg1 = tmpReg, labelSymbol = loopvarSymbol)
+                            it += IRInstruction(Opcode.STOREM, elementDt, reg1 = tmpReg, labelSymbol = loopvarSymbol)
                         }
                         result += translateNode(forLoop.statements)
                         val jumpChunk = IRCodeChunk(null, null)
@@ -491,10 +513,9 @@ class IRCodeGen(
                         result += jumpChunk
                         result += IRCodeChunk(endLabel, null)
                     }
-                    iterable.type.isSplitWordArray -> {
+                    iterable.type.isSplitWordArray || iterable.type.isPointerArray -> {
                         // iterate over lsb/msb split word array
-                        val elementDt = iterable.type.elementType()
-                        if(!elementDt.isWord)
+                        if(elementDt!=IRDataType.WORD)
                             throw AssemblyError("weird dt")
                         addInstr(result, IRInstruction(Opcode.LOAD, IRDataType.BYTE, reg1=indexReg, immediate = 0), null)
                         result += IRCodeChunk(loopLabel, null).also {
@@ -504,7 +525,7 @@ class IRCodeGen(
                             it += IRInstruction(Opcode.LOADX, IRDataType.BYTE, reg1=tmpRegMsb, reg2=indexReg, labelSymbol=iterable.name+"_msb")
                             it += IRInstruction(Opcode.LOADX, IRDataType.BYTE, reg1=tmpRegLsb, reg2=indexReg, labelSymbol=iterable.name+"_lsb")
                             it += IRInstruction(Opcode.CONCAT, IRDataType.BYTE, reg1=concatReg, reg2=tmpRegMsb, reg3=tmpRegLsb)
-                            it += IRInstruction(Opcode.STOREM, irType(elementDt), reg1=concatReg, labelSymbol = loopvarSymbol)
+                            it += IRInstruction(Opcode.STOREM, elementDt, reg1=concatReg, labelSymbol = loopvarSymbol)
                         }
                         result += translateNode(forLoop.statements)
                         result += IRCodeChunk(null, null).also {
@@ -548,7 +569,7 @@ class IRCodeGen(
         val step = iterable.step.number.toInt()
         if (step==0)
             throw AssemblyError("step 0")
-        require(forLoop.variable.name == loopvar.scopedName)
+        require(forLoop.variable.name == loopvar.scopedNameString)
         val loopvarSymbol = forLoop.variable.name
         val loopvarDt = when(loopvar) {
             is StMemVar -> loopvar.dt
@@ -634,7 +655,7 @@ class IRCodeGen(
 
     private fun translateForInConstantRange(forLoop: PtForLoop, loopvar: StNode): IRCodeChunks {
         val loopLabel = createLabelName()
-        require(forLoop.variable.name == loopvar.scopedName)
+        require(forLoop.variable.name == loopvar.scopedNameString)
         val loopvarSymbol = forLoop.variable.name
         val loopvarDt = when(loopvar) {
             is StMemVar -> loopvar.dt
@@ -771,7 +792,7 @@ class IRCodeGen(
         code += if(factor==0.0) {
             IRInstruction(Opcode.LOAD, IRDataType.FLOAT, fpReg1 = fpReg, immediateFp = 0.0)
         } else {
-            IRInstruction(Opcode.MUL, IRDataType.FLOAT, fpReg1 = fpReg, immediateFp = factor)
+            IRInstruction(Opcode.MULS, IRDataType.FLOAT, fpReg1 = fpReg, immediateFp = factor)
         }
         return code
     }
@@ -789,38 +810,40 @@ class IRCodeGen(
             val factorReg = registers.next(IRDataType.FLOAT)
             code += IRInstruction(Opcode.LOAD, IRDataType.FLOAT, fpReg1=factorReg, immediateFp = factor)
             code += if(knownAddress!=null)
-                IRInstruction(Opcode.MULM, IRDataType.FLOAT, fpReg1 = factorReg, address = knownAddress)
+                IRInstruction(Opcode.MULSM, IRDataType.FLOAT, fpReg1 = factorReg, address = knownAddress)
             else
-                IRInstruction(Opcode.MULM, IRDataType.FLOAT, fpReg1 = factorReg, labelSymbol = symbol)
+                IRInstruction(Opcode.MULSM, IRDataType.FLOAT, fpReg1 = factorReg, labelSymbol = symbol)
         }
         return code
     }
 
-    internal fun multiplyByConst(dt: IRDataType, reg: Int, factor: Int): IRCodeChunk {
+    internal fun multiplyByConst(dt: DataType, reg: Int, factor: Int): IRCodeChunk {
+        val irdt = irType(dt)
         val code = IRCodeChunk(null, null)
         if(factor==1)
             return code
         val pow2 = powersOfTwoInt.indexOf(factor)
         if(pow2==1) {
             // just shift 1 bit
-            code += IRInstruction(Opcode.LSL, dt, reg1=reg)
+            code += IRInstruction(Opcode.LSL, irdt, reg1=reg)
         }
         else if(pow2>=1) {
             // just shift multiple bits
             val pow2reg = registers.next(IRDataType.BYTE)
             code += IRInstruction(Opcode.LOAD, IRDataType.BYTE, reg1=pow2reg, immediate = pow2)
-            code += IRInstruction(Opcode.LSLN, dt, reg1=reg, reg2=pow2reg)
+            code += IRInstruction(Opcode.LSLN, irdt, reg1=reg, reg2=pow2reg)
         } else {
             code += if (factor == 0) {
-                IRInstruction(Opcode.LOAD, dt, reg1=reg, immediate = 0)
+                IRInstruction(Opcode.LOAD, irdt, reg1=reg, immediate = 0)
             } else {
-                IRInstruction(Opcode.MUL, dt, reg1=reg, immediate = factor)
+                val opcode = if(dt.isSigned) Opcode.MULS else Opcode.MUL
+                IRInstruction(opcode, irdt, reg1=reg, immediate = factor)
             }
         }
         return code
     }
 
-    internal fun multiplyByConstInplace(dt: IRDataType, knownAddress: Int?, symbol: String?, factor: Int): IRCodeChunk {
+    internal fun multiplyByConstInplace(dt: IRDataType, signed: Boolean, knownAddress: Int?, symbol: String?, factor: Int): IRCodeChunk {
         val code = IRCodeChunk(null, null)
         if(factor==1)
             return code
@@ -850,10 +873,11 @@ class IRCodeGen(
             else {
                 val factorReg = registers.next(dt)
                 code += IRInstruction(Opcode.LOAD, dt, reg1=factorReg, immediate = factor)
+                val opcode = if(signed) Opcode.MULSM else Opcode.MULM
                 code += if(knownAddress!=null)
-                    IRInstruction(Opcode.MULM, dt, reg1=factorReg, address = knownAddress)
+                    IRInstruction(opcode, dt, reg1=factorReg, address = knownAddress)
                 else
-                    IRInstruction(Opcode.MULM, dt, reg1=factorReg, labelSymbol = symbol)
+                    IRInstruction(opcode, dt, reg1=factorReg, labelSymbol = symbol)
             }
         }
         return code
@@ -1070,7 +1094,7 @@ class IRCodeGen(
                 }
                 // evaluate jump address expression into a register and jump indirectly to it
                 val tr = expressionEval.translateExpression(goto.target)
-                for(i in tr.chunks.flatMap { it.instructions }) {
+                for(i in tr.chunks.flatMap { c -> c.instructions }) {
                     it += i
                 }
                 it += IRInstruction(Opcode.JUMPI, reg1 = tr.resultReg)
@@ -1653,7 +1677,7 @@ class IRCodeGen(
                 translateSimple(cond, Opcode.BSTEQ, false)
             }
             is PtTypeCast -> {
-                require(cond.type.isBool && cond.value.type.isNumeric)
+                require(cond.type.isBool && (cond.value.type.isNumeric || cond.value.type.isPointer))
                 translateSimple(cond, Opcode.BSTEQ, false)
             }
             is PtIdentifier, is PtArrayIndexer, is PtContainmentCheck -> {
@@ -1669,6 +1693,9 @@ class IRCodeGen(
             is PtBinaryExpression -> {
                 translateBinExpr(cond)
             }
+            is PtPointerDeref -> {
+                translateSimple(cond, Opcode.BSTEQ, false)
+            }
             else -> throw AssemblyError("weird if condition ${ifElse.condition}")
         }
         return result
@@ -1743,9 +1770,7 @@ class IRCodeGen(
     private fun isIndirectJump(jump: PtJump): Boolean {
         if(jump.target.asConstInteger()!=null)
             return false
-        val identifier = jump.target as? PtIdentifier
-        if(identifier==null)
-            return true
+        val identifier = jump.target as? PtIdentifier ?: return true
         val symbol = symbolTable.lookup(identifier.name)
         return symbol?.type==StNodeType.MEMVAR || symbol?.type==StNodeType.STATICVAR
     }
@@ -1836,7 +1861,7 @@ class IRCodeGen(
                 is PtVariable, is PtConstant, is PtMemMapped -> { /* vars should be looked up via symbol table */ }
                 is PtAlign -> TODO("ir support for inline %align")
                 is PtSub -> {
-                    val sub = IRSubroutine(child.name, translate(child.parameters), child.returns, child.position)
+                    val sub = IRSubroutine(child.name, translateParameters(child.signature.children), child.signature.returns, child.position)
                     for (subchild in child.children) {
                         translateNode(subchild).forEach { sub += it }
                     }
@@ -1885,21 +1910,22 @@ class IRCodeGen(
                         }
                     }
                 }
+                is PtStructDecl -> { /* do nothing, should be found in the symbol table */ }
                 else -> TODO("weird block child node $child")
             }
         }
         return irBlock
     }
 
-    private fun translate(parameters: List<PtSubroutineParameter>): List<IRSubroutine.IRParam> {
+    private fun translateParameters(parameters: List<PtNode>): List<IRSubroutine.IRParam> {
         val result = mutableListOf<IRSubroutine.IRParam>()
         parameters.forEach {
+            it as PtSubroutineParameter
             if(it.register==null) {
-                val flattenedName = it.definingISub()!!.name + "." + it.name
-                if (symbolTable.lookup(flattenedName) == null)
-                    TODO("fix missing lookup for: $flattenedName   parameter")
-                val orig = symbolTable.lookup(flattenedName) as StStaticVariable
-                result += IRSubroutine.IRParam(flattenedName, orig.dt)
+                require('.' in it.name) { "even parameter names should have been made fully scoped by now" }
+                val orig = symbolTable.lookup(it.name) as? StStaticVariable
+                    ?: TODO("fix missing lookup for: ${it.name}   parameter")
+                result += IRSubroutine.IRParam(it.name, orig.dt)
             } else {
                 val reg = it.register
                 require(reg in Cx16VirtualRegisters) { "can only use R0-R15 'registers' here" }
@@ -1924,7 +1950,7 @@ class IRCodeGen(
 
     internal fun isOne(expression: PtExpression): Boolean = (expression as? PtNumber)?.number==1.0 || (expression as? PtBool)?.value==true
 
-    fun makeSyscall(syscall: IMSyscall, params: List<Pair<IRDataType, Int>>, returns: Pair<IRDataType, Int>?, label: String?=null): IRCodeChunk {
+    internal fun makeSyscall(syscall: IMSyscall, params: List<Pair<IRDataType, Int>>, returns: Pair<IRDataType, Int>?, label: String?=null): IRCodeChunk {
         return IRCodeChunk(label, null).also {
             val args = params.map { (dt, reg)->
                 FunctionCallArgs.ArgumentSpec("", null, FunctionCallArgs.RegSpec(dt, reg, null))
@@ -1935,9 +1961,7 @@ class IRCodeGen(
         }
     }
 
-    fun registerTypes(): Map<Int, IRDataType> = registers.getTypes()
-
-    fun setCpuRegister(registerOrFlag: RegisterOrStatusflag, paramDt: IRDataType, resultReg: Int, resultFpReg: Int): IRCodeChunk {
+    internal fun setCpuRegister(registerOrFlag: RegisterOrStatusflag, paramDt: IRDataType, resultReg: Int, resultFpReg: Int): IRCodeChunk {
         val chunk = IRCodeChunk(null, null)
         when(registerOrFlag.registerOrPair) {
             RegisterOrPair.A -> chunk += IRInstruction(Opcode.STOREHA, IRDataType.BYTE, reg1=resultReg)
@@ -1954,10 +1978,83 @@ class IRCodeGen(
             null -> when(registerOrFlag.statusflag) {
                 // TODO: do the statusflag argument as last
                 Statusflag.Pc -> chunk += IRInstruction(Opcode.LSR, paramDt, reg1=resultReg)
-                else -> throw AssemblyError("weird statusflag as param")
+                else -> throw AssemblyError("unsupported statusflag as param")
             }
             else -> throw AssemblyError("unsupported register arg")
         }
         return chunk
     }
+
+    internal fun evaluatePointerAddressIntoReg(result: MutableList<IRCodeChunkBase>, deref: PtPointerDeref): Pair<Int, UInt> {
+        // calculates the pointer address and returns the register it's in + remaining offset into the struct  (so that LOADFIELD/STOREFIELD instructions can be used)
+        val pointerTr = expressionEval.translateExpression(deref.startpointer)
+        result += pointerTr.chunks
+        val (instructions, offset) = expressionEval.traverseRestOfDerefChainToCalculateFinalAddress(deref, pointerTr.resultReg)
+        result += instructions
+        return pointerTr.resultReg to offset
+    }
+
+    internal fun storeValueAtPointersLocation(result: MutableList<IRCodeChunkBase>, addressReg: Int, offset: UInt, type: DataType, valueIsZero: Boolean, existingValueRegister: Int) {
+        if(offset==0u) {
+            val irdt = irType(type)
+            val instr = if(type.isFloat) {
+                if (valueIsZero) IRInstruction(Opcode.STOREZI, IRDataType.FLOAT, reg1 = addressReg)
+                else IRInstruction(Opcode.STOREI, IRDataType.FLOAT, fpReg1 = existingValueRegister, reg1 = addressReg)
+            } else {
+                if (valueIsZero) IRInstruction(Opcode.STOREZI, irdt, reg1 = addressReg)
+                else IRInstruction(Opcode.STOREI, irdt, reg1 = existingValueRegister, reg2 = addressReg)
+            }
+            addInstr(result, instr, null)
+            return
+        }
+
+        // store with field offset
+        var valueRegister = existingValueRegister
+        val irdt = irType(type)
+        if(valueIsZero && valueRegister<0) {
+            if(type.isFloat) {
+                valueRegister = registers.next(IRDataType.FLOAT)
+                addInstr(result, IRInstruction(Opcode.LOAD, IRDataType.FLOAT, fpReg1 = valueRegister, immediateFp = 0.0), null)
+            } else {
+                valueRegister = registers.next(irdt)
+                addInstr(result, IRInstruction(Opcode.LOAD, irdt, reg1 = valueRegister, immediate = 0), null)
+            }
+        }
+        val instr = if (type.isFloat)
+            IRInstruction(Opcode.STOREFIELD, IRDataType.FLOAT, fpReg1 = valueRegister, reg1 = addressReg, immediate = offset.toInt())
+        else
+            IRInstruction(Opcode.STOREFIELD, irdt, reg1 = valueRegister, reg2 = addressReg, immediate = offset.toInt())
+        addInstr(result, instr, null)
+    }
+
+    internal fun loadIndexReg(index: PtExpression, itemsize: Int, wordIndex: Boolean, arrayIsSplitWords: Boolean): Pair<IRCodeChunks, Int> {
+        // returns the code to load the Index into the register, which is also returned.
+
+        require(index !is PtNumber) { "index should not be a constant number here, calling code should handle that in a more efficient way" }
+
+        val result = mutableListOf<IRCodeChunkBase>()
+
+        if(wordIndex) {
+            val tr = expressionEval.translateExpression(index)
+            addToResult(result, tr, tr.resultReg, -1)
+            var indexReg = tr.resultReg
+            if(tr.dt==IRDataType.BYTE) {
+                indexReg = registers.next(IRDataType.WORD)
+                addInstr(result, IRInstruction(Opcode.EXT, IRDataType.BYTE, reg1=indexReg, reg2=tr.resultReg), null)
+            }
+            result += multiplyByConst(DataType.UWORD, indexReg, itemsize)
+            return Pair(result, indexReg)
+        }
+
+        // regular byte size index value.
+        val byteIndexTr = expressionEval.translateExpression(index)
+        addToResult(result, byteIndexTr, byteIndexTr.resultReg, -1)
+
+        if(itemsize==1 || arrayIsSplitWords)
+            return Pair(result, byteIndexTr.resultReg)
+
+        result += multiplyByConst(DataType.UBYTE, byteIndexTr.resultReg, itemsize)
+        return Pair(result, byteIndexTr.resultReg)
+    }
+
 }

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

@@ -23,6 +23,7 @@ class IRPeepholeOptimizer(private val irprog: IRProgram) {
     }
 
     private fun optimizeOnlyJoinChunks() {
+        // this chunk-joining is REQUIRED (optimization or no) to end up with a structurally sound chunk list
         irprog.foreachSub { sub ->
             joinChunks(sub)
             removeEmptyChunks(sub)
@@ -52,6 +53,7 @@ class IRPeepholeOptimizer(private val irprog: IRProgram) {
                                 || removeWeirdBranches(chunk1, chunk2, indexedInstructions)
                                 || removeDoubleSecClc(chunk1, indexedInstructions)
                                 || cleanupPushPop(chunk1, indexedInstructions)
+                                || simplifyConstantReturns(chunk1, indexedInstructions)
                     } while (changed)
                 }
             }
@@ -84,7 +86,7 @@ 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 merge both labels into 1.
+            If next chunk has label -> label name should be the same, in which case remove original, otherwise leave everything untouched.
             If is last chunk -> keep chunk in place because of the label.
         Empty Code chunk without label ->
             should not have been generated! ERROR.
@@ -111,14 +113,6 @@ class IRPeepholeOptimizer(private val irprog: IRProgram) {
                             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!!
-                                    }
-                                }
                             }
                         }
                     }
@@ -364,7 +358,7 @@ class IRPeepholeOptimizer(private val irprog: IRProgram) {
         var changed = false
         indexedInstructions.reversed().forEach { (idx, ins) ->
             when (ins.opcode) {
-                Opcode.DIV, Opcode.DIVS, Opcode.MUL, Opcode.MOD -> {
+                Opcode.DIV, Opcode.DIVS, Opcode.MUL, Opcode.MULS, Opcode.MOD -> {
                     if (ins.immediate == 1) {
                         chunk.instructions.removeAt(idx)
                         changed = true
@@ -462,4 +456,23 @@ class IRPeepholeOptimizer(private val irprog: IRProgram) {
         }
         return changed
     }
+
+    private fun simplifyConstantReturns(chunk: IRCodeChunk, indexedInstructions: List<IndexedValue<IRInstruction>>): Boolean {
+        //  use a RETURNI when a RETURNR is just returning a constant that was loaded into a register just before
+        var changed = false
+        indexedInstructions.reversed().forEach { (idx, ins) ->
+            if(ins.opcode==Opcode.RETURNR) {
+                if(idx>0) {
+                    val insBefore = chunk.instructions[idx-1]
+                    if(insBefore.opcode == Opcode.LOAD && insBefore.immediate!=null) {
+                        val constvalue = insBefore.immediate!!
+                        chunk.instructions[idx] = IRInstruction(Opcode.RETURNI, ins.type, immediate = constvalue)
+                        chunk.instructions.removeAt(idx-1)
+                        changed = true
+                    }
+                }
+            }
+        }
+        return changed
+    }
 }

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

@@ -27,6 +27,9 @@ class IRUnusedCodeRemover(
         // 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) }
+
+        // check if there are symbols referenced elsewhere that we should not prune (even though the rest of the block is empty)
+
         blockVars.forEach { stVar ->
             irprog.allSubs().flatMap { it.chunks }.forEach { chunk ->
                 chunk.instructions.forEach { ins ->
@@ -47,7 +50,50 @@ class IRUnusedCodeRemover(
             }
         }
 
+        val blockStructs = irprog.st.allStructDefs().filter { it.name.startsWith(prefix) }
+        blockStructs.forEach { struct ->
+            irprog.st.allStructInstances().forEach { instance ->
+                if(instance.structName == struct.name)
+                    return  // a struct instance is declared using this struct type
+            }
+            irprog.st.allVariables().forEach { variable ->
+                if(variable.dt.isPointer || variable.dt.isStructInstance)
+                    if(struct.name == variable.dt.subType!!.scopedNameString)
+                        return   // a variable exists with the struct as (pointer) type
+            }
+        }
+
         irprog.st.removeTree(blockLabel)
+        removeBlockInits(irprog, blockLabel)
+    }
+
+    private fun removeBlockInits(code: IRProgram, blockLabel: String) {
+        val instructions = code.globalInits.instructions
+        instructions.toTypedArray().forEach {ins ->
+            if(ins.labelSymbol?.startsWith(blockLabel)==true) {
+                instructions.remove(ins)
+            }
+        }
+
+        // remove stray loads
+        instructions.toTypedArray().forEach { ins ->
+            if(ins.opcode in arrayOf(Opcode.LOAD, Opcode.LOADR, Opcode.LOADM)) {
+                if(ins.reg1!=0) {
+                    if(instructions.count { it.reg1==ins.reg1 || it.reg2==ins.reg1 } <2) {
+                        if(ins.labelSymbol!=null)
+                            code.st.removeIfExists(ins.labelSymbol!!)
+                        instructions.remove(ins)
+                    }
+                }
+                else if(ins.fpReg1!=0) {
+                    if (instructions.count { it.fpReg1 == ins.fpReg1 || it.fpReg2 == ins.fpReg1 } < 2) {
+                        if(ins.labelSymbol!=null)
+                            code.st.removeIfExists(ins.labelSymbol!!)
+                        instructions.remove(ins)
+                    }
+                }
+            }
+        }
     }
 
     private fun removeUnusedSubroutines(): Int {

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

@@ -14,6 +14,12 @@ fun convertStToIRSt(sourceSt: SymbolTable?): IRSymbolTable {
                 StNodeType.MEMVAR -> st.add(convert(it.value as StMemVar))
                 StNodeType.CONSTANT -> st.add(convert(it.value as StConstant))
                 StNodeType.MEMORYSLAB -> st.add(convert(it.value as StMemorySlab))
+                StNodeType.STRUCTINSTANCE -> {
+                    val instance = it.value as StStructInstance
+                    val struct = sourceSt.lookup(instance.structName) as StStruct
+                    st.add(convert(instance, struct.fields))
+                }
+                StNodeType.STRUCT -> st.add(convert(it.value as StStruct))
                 else -> { }
             }
         }
@@ -37,12 +43,17 @@ fun convertStToIRSt(sourceSt: SymbolTable?): IRSymbolTable {
 }
 
 
-private fun convert(variable: StStaticVariable): IRStStaticVariable {
+private fun convert(struct: StStruct): IRStStructDef =
+    IRStStructDef(struct.scopedNameString, struct.fields, struct.size)
 
-    fun convertArrayElt(elt: StArrayElement): IRStArrayElement = if(elt.boolean!=null)
-        IRStArrayElement(elt.boolean, null, elt.addressOfSymbol)
-    else
-        IRStArrayElement(null, elt.number, elt.addressOfSymbol)
+
+private fun convertArrayElt(elt: StArrayElement): IRStArrayElement = if(elt.boolean!=null)
+    IRStArrayElement(elt.boolean, null, elt.addressOfSymbol)
+else
+    IRStArrayElement(null, elt.number, elt.addressOfSymbol)
+
+
+private fun convert(variable: StStaticVariable): IRStStaticVariable {
 
     if('.' in variable.name) {
         return IRStStaticVariable(variable.name,
@@ -52,7 +63,8 @@ private fun convert(variable: StStaticVariable): IRStStaticVariable {
             variable.initializationArrayValue?.map { convertArrayElt(it) },
             variable.length,
             variable.zpwish,
-            variable.align)
+            variable.align,
+            variable.dirty)
     } else {
         fun fixupAddressOfInArray(array: List<StArrayElement>?): List<IRStArrayElement>? {
             if(array==null)
@@ -61,14 +73,14 @@ private fun convert(variable: StStaticVariable): IRStStaticVariable {
             array.forEach {
                 if(it.addressOfSymbol!=null) {
                     val target = variable.lookup(it.addressOfSymbol!!) ?: throw NoSuchElementException("can't find variable ${it.addressOfSymbol}")
-                    newArray.add(IRStArrayElement(null, null, target.scopedName))
+                    newArray.add(IRStArrayElement(null, null, target.scopedNameString))
                 } else {
                     newArray.add(convertArrayElt(it))
                 }
             }
             return newArray
         }
-        val scopedName = variable.scopedName
+        val scopedName = variable.scopedNameString
         return IRStStaticVariable(scopedName,
             variable.dt,
             variable.initializationNumericValue,
@@ -76,7 +88,8 @@ private fun convert(variable: StStaticVariable): IRStStaticVariable {
             fixupAddressOfInArray(variable.initializationArrayValue),
             variable.length,
             variable.zpwish,
-            variable.align
+            variable.align,
+            variable.dirty
         )
     }
 }
@@ -92,7 +105,7 @@ private fun convert(variable: StMemVar): IRStMemVar {
         )
     } else {
         val scopedName = try {
-            variable.scopedName
+            variable.scopedNameString
         } catch (_: UninitializedPropertyAccessException) {
             variable.name
         }
@@ -107,7 +120,7 @@ private fun convert(constant: StConstant): IRStConstant {
         constant.name
     } else {
         try {
-            constant.scopedName
+            constant.scopedNameString
         } catch (_: UninitializedPropertyAccessException) {
             constant.name
         }
@@ -120,12 +133,17 @@ private fun convert(variable: StMemorySlab): IRStMemorySlab {
     return if('.' in variable.name)
         IRStMemorySlab(variable.name, variable.size, variable.align)
     else
-        IRStMemorySlab("prog8_slabs.${variable.name}", variable.size, variable.align)
+        IRStMemorySlab("$StMemorySlabPrefix.${variable.name}", variable.size, variable.align)
 }
 
-/*
+
+private fun convert(instance: StStructInstance, fields: Iterable<Pair<DataType, String>>): IRStStructInstance {
+    val values = fields.zip(instance.initialValues).map { (field, value) ->
+        val elt = convertArrayElt(value)
+        IRStructInitValue(field.first.base, elt)
+    }
+    return IRStStructInstance(instance.name, instance.structName, values, instance.size)
+}
 
 
-
-
- */
+internal const val StMemorySlabPrefix = "prog8_slabs"       // TODO also add  ".prog8_memoryslab_"  ?

codeGenIntermediate/test/Dummies.kt

@@ -3,7 +3,9 @@ import prog8.code.core.*
 
 internal object DummyMemsizer : IMemSizer {
     override fun memorySize(dt: DataType, numElements: Int?): Int {
-        if(dt.isArray || dt.isSplitWordArray) {
+        if(dt.isPointerArray)
+            return 2 * numElements!!
+        else if(dt.isArray || dt.isSplitWordArray) {
             require(numElements!=null)
             return when(dt.sub) {
                 BaseDataType.BOOL, BaseDataType.BYTE, BaseDataType.UBYTE -> numElements
@@ -66,7 +68,7 @@ internal class ErrorReporterForTests(private val throwExceptionAtReportIfErrors:
 
     override fun noErrors(): Boolean  = errors.isEmpty()
     override fun noErrorForLine(position: Position) = !errors.any { ":${position.line}:" in it }
-    override fun print_single_error(errormessage: String) { /* prints nothing in tests */ }
+    override fun printSingleError(errormessage: String) { /* prints nothing in tests */ }
 
     override fun report() {
         infos.forEach { println("UNITTEST COMPILATION REPORT: INFO: $it") }

codeGenIntermediate/test/TestIRPeepholeOpt.kt

@@ -53,7 +53,7 @@ class TestIRPeepholeOpt: FunSpec({
         irProg.chunks().single().instructions.size shouldBe 1
     }
 
-    test("remove jmp to label below") {
+    test("remove jmp to label below but keep labels") {
         val c1 = IRCodeChunk("main.start", null)
         c1 += IRInstruction(Opcode.JUMP, labelSymbol = "label")
         val c2 = IRCodeChunk("label", null)
@@ -69,13 +69,16 @@ class TestIRPeepholeOpt: FunSpec({
         irProg.chunks().flatMap { it.instructions }.size shouldBe 5
         val opt = IRPeepholeOptimizer(irProg)
         opt.optimize(true, ErrorReporterForTests())
-        irProg.chunks().size shouldBe 3
-        irProg.chunks()[0].label shouldBe "main.start"
-        irProg.chunks()[1].label shouldBe "label2"
-        irProg.chunks()[2].label shouldBe "label3"
-        irProg.chunks()[0].isEmpty() shouldBe true
-        irProg.chunks()[1].isEmpty() shouldBe false
-        irProg.chunks()[2].isEmpty() shouldBe true
+        val chunks = irProg.chunks()
+        chunks.size shouldBe 4
+        chunks[0].label shouldBe "main.start"
+        chunks[1].label shouldBe "label"
+        chunks[2].label shouldBe "label2"
+        chunks[3].label shouldBe "label3"
+        chunks[0].isEmpty() shouldBe true
+        chunks[1].isEmpty() shouldBe true
+        chunks[2].isEmpty() shouldBe false
+        chunks[3].isEmpty() shouldBe true
         val instr = irProg.chunks().flatMap { it.instructions }
         instr.size shouldBe 2
         instr[0].opcode shouldBe Opcode.JUMP

codeGenIntermediate/test/TestVmCodeGen.kt

@@ -52,6 +52,7 @@ class TestVmCodeGen: FunSpec({
             DataType.UBYTE,
             ZeropageWish.DONTCARE,
             0u,
+            false,
             null,
             null,
             Position.DUMMY
@@ -61,6 +62,7 @@ class TestVmCodeGen: FunSpec({
             DataType.arrayFor(BaseDataType.UBYTE),
             ZeropageWish.DONTCARE,
             0u,
+            false,
             null,
             3u,
             Position.DUMMY
@@ -70,6 +72,7 @@ class TestVmCodeGen: FunSpec({
             DataType.arrayFor(BaseDataType.UBYTE),
             ZeropageWish.DONTCARE,
             0u,
+            false,
             null,
             3u,
             Position.DUMMY
@@ -79,6 +82,7 @@ class TestVmCodeGen: FunSpec({
             DataType.WORD,
             ZeropageWish.DONTCARE,
             0u,
+            false,
             null,
             null,
             Position.DUMMY
@@ -167,6 +171,7 @@ class TestVmCodeGen: FunSpec({
             DataType.FLOAT,
             ZeropageWish.DONTCARE,
             0u,
+            false,
             null,
             null,
             Position.DUMMY
@@ -238,6 +243,7 @@ class TestVmCodeGen: FunSpec({
             DataType.FLOAT,
             ZeropageWish.DONTCARE,
             0u,
+            false,
             null,
             null,
             Position.DUMMY
@@ -305,6 +311,7 @@ class TestVmCodeGen: FunSpec({
             DataType.FLOAT,
             ZeropageWish.DONTCARE,
             0u,
+            false,
             null,
             null,
             Position.DUMMY
@@ -360,6 +367,7 @@ class TestVmCodeGen: FunSpec({
             DataType.BYTE,
             ZeropageWish.DONTCARE,
             0u,
+            false,
             null,
             null,
             Position.DUMMY
@@ -431,6 +439,7 @@ class TestVmCodeGen: FunSpec({
             DataType.BYTE,
             ZeropageWish.DONTCARE,
             0u,
+            false,
             null,
             null,
             Position.DUMMY
@@ -498,6 +507,7 @@ class TestVmCodeGen: FunSpec({
             DataType.BYTE,
             ZeropageWish.DONTCARE,
             0u,
+            false,
             null,
             null,
             Position.DUMMY
@@ -554,11 +564,8 @@ 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
-        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]
+        irChunks[0].instructions.size shouldBe 1
+        val callInstr = irChunks[0].instructions[0]
         callInstr.opcode shouldBe Opcode.CALL
         callInstr.address shouldBe 0x5000
     }

codeOptimizers/build.gradle.kts

@@ -1,5 +1,3 @@
-import org.jetbrains.kotlin.gradle.dsl.JvmTarget
-
 plugins {
     kotlin("jvm")
 }
@@ -8,7 +6,7 @@ dependencies {
     implementation(project(":codeCore"))
     implementation(project(":compilerAst"))
     // implementation("org.jetbrains.kotlin:kotlin-stdlib-jdk8")
-    implementation("com.michael-bull.kotlin-result:kotlin-result-jvm:2.0.1")
+    implementation("com.michael-bull.kotlin-result:kotlin-result-jvm:2.1.0")
     // implementation "org.jetbrains.kotlin:kotlin-reflect"
 }
 

codeOptimizers/src/prog8/optimizer/ConstExprEvaluator.kt

@@ -5,10 +5,7 @@ import prog8.ast.FatalAstException
 import prog8.ast.Program
 import prog8.ast.expressions.FunctionCallExpression
 import prog8.ast.expressions.NumericLiteral
-import prog8.code.core.BaseDataType
-import prog8.code.core.Position
-import prog8.code.core.isInteger
-import prog8.code.core.isIntegerOrBool
+import prog8.code.core.*
 import kotlin.math.*
 
 
@@ -70,52 +67,45 @@ class ConstExprEvaluator {
     }
 
     private fun bitwiseXor(left: NumericLiteral, right: NumericLiteral): NumericLiteral {
-        if(left.type==BaseDataType.UBYTE || left.type==BaseDataType.BOOL) {
-            if(right.type.isIntegerOrBool) {
-                return NumericLiteral(BaseDataType.UBYTE, (left.number.toInt() xor (right.number.toInt() and 255)).toDouble(), left.position)
-            }
-        } else if(left.type==BaseDataType.UWORD) {
-            if(right.type.isInteger) {
-                return NumericLiteral(BaseDataType.UWORD, (left.number.toInt() xor right.number.toInt() and 65535).toDouble(), left.position)
-            }
-        } else if(left.type==BaseDataType.LONG) {
-            if(right.type.isInteger) {
-                return NumericLiteral.optimalNumeric((left.number.toInt() xor right.number.toInt()).toDouble(), left.position)
+        if(right.type.isIntegerOrBool) {
+            val leftDt = left.type
+            if(leftDt.isByteOrBool)
+                return NumericLiteral(BaseDataType.UBYTE, ((left.number.toInt() xor right.number.toInt()) and 255).toDouble(), left.position)
+            else if(leftDt.isInteger) {
+                if (leftDt == BaseDataType.UWORD || leftDt == BaseDataType.WORD)
+                    return NumericLiteral(BaseDataType.UWORD, ((left.number.toInt() xor right.number.toInt()) and 65535).toDouble(), left.position)
+                else if (leftDt == BaseDataType.LONG)
+                    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 {
-        if(left.type==BaseDataType.UBYTE || left.type==BaseDataType.BOOL) {
-            if(right.type.isIntegerOrBool) {
-                return NumericLiteral(BaseDataType.UBYTE, (left.number.toInt() or (right.number.toInt() and 255)).toDouble(), left.position)
-            }
-        } else if(left.type==BaseDataType.UWORD) {
-            if(right.type.isInteger) {
-                return NumericLiteral(BaseDataType.UWORD, (left.number.toInt() or right.number.toInt() and 65535).toDouble(), left.position)
-            }
-        } else if(left.type==BaseDataType.LONG) {
-            if(right.type.isInteger) {
-                return NumericLiteral.optimalNumeric((left.number.toInt() or right.number.toInt()).toDouble(), left.position)
+        if(right.type.isIntegerOrBool) {
+            val leftDt = left.type
+            if(leftDt.isByteOrBool)
+                return NumericLiteral(BaseDataType.UBYTE, ((left.number.toInt() or right.number.toInt()) and 255).toDouble(), left.position)
+            else if(leftDt.isInteger) {
+                if (leftDt == BaseDataType.UWORD || leftDt == BaseDataType.WORD)
+                    return NumericLiteral(BaseDataType.UWORD, ((left.number.toInt() or right.number.toInt()) and 65535).toDouble(), left.position)
+                else if (leftDt == BaseDataType.LONG)
+                    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 {
-        if(left.type==BaseDataType.UBYTE || left.type==BaseDataType.BOOL) {
-            if(right.type.isIntegerOrBool) {
-                return NumericLiteral(BaseDataType.UBYTE, (left.number.toInt() and (right.number.toInt() and 255)).toDouble(), left.position)
-            }
-        } else if(left.type==BaseDataType.UWORD) {
-            if(right.type.isInteger) {
-                return NumericLiteral(BaseDataType.UWORD, (left.number.toInt() and right.number.toInt() and 65535).toDouble(), left.position)
-            }
-        } else if(left.type==BaseDataType.LONG) {
-            if(right.type.isInteger) {
-                return NumericLiteral.optimalNumeric((left.number.toInt() and right.number.toInt()).toDouble(), left.position)
+        if(right.type.isIntegerOrBool) {
+            val leftDt = left.type
+            if(leftDt.isByteOrBool)
+                return NumericLiteral(BaseDataType.UBYTE, ((left.number.toInt() and right.number.toInt()) and 255).toDouble(), left.position)
+            else if(leftDt.isInteger) {
+                if (leftDt == BaseDataType.UWORD || leftDt == BaseDataType.WORD)
+                    return NumericLiteral(BaseDataType.UWORD, ((left.number.toInt() and right.number.toInt()) and 65535).toDouble(), left.position)
+                else if (leftDt == BaseDataType.LONG)
+                    return NumericLiteral.optimalNumeric((left.number.toInt() and right.number.toInt()).toDouble(), left.position)
             }
         }
         throw ExpressionError("cannot calculate $left & $right", left.position)

codeOptimizers/src/prog8/optimizer/ConstantFoldingOptimizer.kt

@@ -27,8 +27,8 @@ class ConstantFoldingOptimizer(private val program: Program, private val errors:
         // @( &thing )  -->  thing  (but only if thing is a byte type!)
         val addrOf = memread.addressExpression as? AddressOf
         if(addrOf!=null) {
-            if(addrOf.identifier.inferType(program).isBytes)
-                return listOf(IAstModification.ReplaceNode(memread, addrOf.identifier, parent))
+            if(addrOf.identifier?.inferType(program)?.isBytes==true)
+                return listOf(IAstModification.ReplaceNode(memread, addrOf.identifier!!, parent))
         }
         return noModifications
     }
@@ -129,7 +129,7 @@ class ConstantFoldingOptimizer(private val program: Program, private val errors:
                     return listOf(IAstModification.ReplaceNode(expr, newArray, parent))
                 }
                 else {
-                    val leftTarget = (expr.left as? IdentifierReference)?.targetVarDecl(program)
+                    val leftTarget = (expr.left as? IdentifierReference)?.targetVarDecl()
                     if(leftTarget!=null && leftTarget.origin==VarDeclOrigin.ARRAYLITERAL)
                         throw FatalAstException("shouldn't see an array literal converted to an autovar here")
                 }
@@ -332,15 +332,19 @@ class ConstantFoldingOptimizer(private val program: Program, private val errors:
 
             val constIndex = arrayIndexedExpression.indexer.constIndex()
             if (constIndex != null) {
-                val arrayVar = arrayIndexedExpression.arrayvar.targetVarDecl(program)
-                if(arrayVar!=null) {
-                    val array =arrayVar.value as? ArrayLiteral
-                    if(array!=null) {
-                        val value = array.value[constIndex].constValue(program)
-                        if(value!=null) {
-                            return listOf(IAstModification.ReplaceNode(arrayIndexedExpression, value, parent))
+                if(arrayIndexedExpression.plainarrayvar!=null) {
+                    val arrayVar = arrayIndexedExpression.plainarrayvar!!.targetVarDecl()
+                    if(arrayVar!=null) {
+                        val array =arrayVar.value as? ArrayLiteral
+                        if(array!=null) {
+                            val value = array.value[constIndex].constValue(program)
+                            if(value!=null) {
+                                return listOf(IAstModification.ReplaceNode(arrayIndexedExpression, value, parent))
+                            }
                         }
                     }
+                } else if(arrayIndexedExpression.pointerderef!=null) {
+                    TODO("constant fold pointer[i]")
                 }
             }
         }
@@ -387,12 +391,11 @@ class ConstantFoldingOptimizer(private val program: Program, private val errors:
         val rangeTo = iterableRange.to as? NumericLiteral
         if(rangeFrom==null || rangeTo==null) return noModifications
 
-        val loopvar = forLoop.loopVar.targetVarDecl(program) ?: return noModifications
+        val loopvar = forLoop.loopVar.targetVarDecl() ?: return noModifications
 
         val stepLiteral = iterableRange.step as? NumericLiteral
-        require(loopvar.datatype.sub == null)
-        val loopvarSimpleDt = loopvar.datatype.base
-        when(loopvarSimpleDt) {
+        require(loopvar.datatype.isBasic)
+        when(val loopvarSimpleDt = loopvar.datatype.base) {
             BaseDataType.UBYTE -> {
                 if(rangeFrom.type != BaseDataType.UBYTE) {
                     // attempt to translate the iterable into ubyte values

codeOptimizers/src/prog8/optimizer/ConstantIdentifierReplacer.kt

@@ -323,7 +323,7 @@ internal class ConstantIdentifierReplacer(
                 val add = BinaryExpression(NumericLiteral(cval.type, cval.number, identifier.position), "+", arrayIdx.indexer.indexExpr, identifier.position)
                 return if(arrayIdx.parent is AssignTarget) {
                     val memwrite = DirectMemoryWrite(add, identifier.position)
-                    val assignTarget = AssignTarget(null, null, memwrite, null, false, identifier.position)
+                    val assignTarget = AssignTarget(null, null, memwrite, null, false, position = identifier.position)
                     listOf(IAstModification.ReplaceNode(arrayIdx.parent, assignTarget, arrayIdx.parent.parent))
                 } else {
                     val memread = DirectMemoryRead(add, identifier.position)

codeOptimizers/src/prog8/optimizer/ExpressionSimplifier.kt

@@ -18,8 +18,8 @@ class ExpressionSimplifier(private val program: Program, private val errors: IEr
 
         // try to statically convert a literal value into one of the desired type
         val literal = typecast.expression as? NumericLiteral
-        if (literal != null) {
-            val newLiteral = literal.cast(typecast.type, typecast.implicit)
+        if (literal != null && typecast.type.isBasic) {
+            val newLiteral = literal.cast(typecast.type.base, typecast.implicit)
             if (newLiteral.isValid && newLiteral.valueOrZero() !== literal) {
                 mods += IAstModification.ReplaceNode(typecast, newLiteral.valueOrZero(), parent)
             }
@@ -33,7 +33,7 @@ class ExpressionSimplifier(private val program: Program, private val errors: IEr
                 mods += IAstModification.ReplaceNode(typecast.expression, subTypecast.expression, typecast)
             }
         } else {
-            if (typecast.expression.inferType(program) issimpletype typecast.type) {
+            if (typecast.expression.inferType(program) istype typecast.type) {
                 // remove duplicate cast
                 mods += IAstModification.ReplaceNode(typecast, typecast.expression, parent)
             }
@@ -49,7 +49,7 @@ class ExpressionSimplifier(private val program: Program, private val errors: IEr
             if(truepart.statements.singleOrNull() is Jump) {
                 return listOf(
                     IAstModification.InsertAfter(ifElse, elsepart, parent as IStatementContainer),
-                    IAstModification.ReplaceNode(elsepart, AnonymousScope(mutableListOf(), elsepart.position), ifElse)
+                    IAstModification.ReplaceNode(elsepart, AnonymousScope.empty(), ifElse)
                 )
             }
             if(elsepart.statements.singleOrNull() is Jump) {
@@ -57,7 +57,7 @@ class ExpressionSimplifier(private val program: Program, private val errors: IEr
                 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(elsepart, AnonymousScope.empty(), ifElse),
                     IAstModification.ReplaceNode(truepart, elsepart, ifElse)
                 )
             }
@@ -242,14 +242,16 @@ class ExpressionSimplifier(private val program: Program, private val errors: IEr
                 }
             }
             if (rightVal?.number == 1.0) {
-                if (rightDt != leftDt) {
-                    val right = NumericLiteral(leftDt.base, rightVal.number, rightVal.position)
+                if (rightDt != leftDt && !(leftDt.isPointer && rightDt.isUnsignedWord)) {
+                    val dt = if(leftDt.isPointer) BaseDataType.UWORD else leftDt.base
+                    val right = NumericLiteral(dt, rightVal.number, rightVal.position)
                     return listOf(IAstModification.ReplaceNode(expr.right, right, expr))
                 }
             }
             else if (rightVal?.number == 0.0) {
-                if (rightDt != leftDt) {
-                    val right = NumericLiteral(leftDt.base, rightVal.number, rightVal.position)
+                if (rightDt != leftDt && !(leftDt.isPointer && rightDt.isUnsignedWord)) {
+                    val dt = if(leftDt.isPointer) BaseDataType.UWORD else leftDt.base
+                    val right = NumericLiteral(dt, rightVal.number, rightVal.position)
                     return listOf(IAstModification.ReplaceNode(expr.right, right, expr))
                 }
             }
@@ -262,14 +264,16 @@ class ExpressionSimplifier(private val program: Program, private val errors: IEr
                 }
             }
             if (rightVal?.number == 1.0) {
-                if(rightDt!=leftDt) {
-                    val right = NumericLiteral(leftDt.base, rightVal.number, rightVal.position)
+                if(rightDt!=leftDt && !(leftDt.isPointer && rightDt.isUnsignedWord)) {
+                    val dt = if(leftDt.isPointer) BaseDataType.UWORD else leftDt.base
+                    val right = NumericLiteral(dt, rightVal.number, rightVal.position)
                     return listOf(IAstModification.ReplaceNode(expr.right, right, expr))
                 }
             }
             else if (rightVal?.number == 0.0) {
-                if(rightDt!=leftDt) {
-                    val right = NumericLiteral(leftDt.base, rightVal.number, rightVal.position)
+                if(rightDt!=leftDt && !(leftDt.isPointer && rightDt.isUnsignedWord)) {
+                    val dt = if(leftDt.isPointer) BaseDataType.UWORD else leftDt.base
+                    val right = NumericLiteral(dt, rightVal.number, rightVal.position)
                     return listOf(IAstModification.ReplaceNode(expr.right, right, expr))
                 }
             }
@@ -423,6 +427,29 @@ class ExpressionSimplifier(private val program: Program, private val errors: IEr
         return noModifications
     }
 
+    override fun after(arrayIndexedExpression: ArrayIndexedExpression, parent: Node): Iterable<IAstModification> {
+        if(arrayIndexedExpression.indexer.constIndex()==0) {
+            if(arrayIndexedExpression.plainarrayvar!=null) {
+                val dt = arrayIndexedExpression.plainarrayvar!!.inferType(program).getOrUndef()
+                if(dt.isPointer) {
+                    // pointer[0]  -->   pointer^^
+                    val deref = PtrDereference(arrayIndexedExpression.plainarrayvar!!.nameInSource, true, arrayIndexedExpression.plainarrayvar!!.position)
+                    return listOf(IAstModification.ReplaceNode(arrayIndexedExpression,deref, parent))
+                }
+            }
+            val ptrDeref = arrayIndexedExpression.pointerderef
+            if(ptrDeref!=null) {
+                val dt = ptrDeref.inferType(program).getOrUndef()
+                if(dt.isPointer) {
+                    // ptr1.ptr2[0] --> ptr1.ptr2^^
+                    val deref = PtrDereference(ptrDeref.chain, true, ptrDeref.position)
+                    return listOf(IAstModification.ReplaceNode(arrayIndexedExpression, deref, parent))
+                }
+            }
+        }
+        return noModifications
+    }
+
     private fun applyAbsorptionLaws(expr: BinaryExpression): Expression? {
         // NOTE: only when the terms are not function calls!!!
         if(expr.left is IFunctionCall || expr.right is IFunctionCall)
@@ -499,7 +526,7 @@ class ExpressionSimplifier(private val program: Program, private val errors: IEr
                 }
                 else if (valueDt issimpletype BaseDataType.BYTE) {
                     // useless lsb() of byte value, but as lsb() returns unsigned, we have to cast now.
-                    val cast = TypecastExpression(arg.expression, BaseDataType.UBYTE, true, arg.position)
+                    val cast = TypecastExpression(arg.expression, DataType.UBYTE, true, arg.position)
                     return listOf(IAstModification.ReplaceNode(functionCallExpr, cast, parent))
                 }
             } else {
@@ -516,7 +543,7 @@ class ExpressionSimplifier(private val program: Program, private val errors: IEr
                 }
                 else if (argDt issimpletype BaseDataType.BYTE) {
                     // useless lsb() of byte value, but as lsb() returns unsigned, we have to cast now.
-                    val cast = TypecastExpression(arg, BaseDataType.UBYTE, true, arg.position)
+                    val cast = TypecastExpression(arg, DataType.UBYTE, true, arg.position)
                     return listOf(IAstModification.ReplaceNode(functionCallExpr, cast, parent))
                 }
             }
@@ -555,12 +582,12 @@ class ExpressionSimplifier(private val program: Program, private val errors: IEr
         if(functionCallExpr.target.nameInSource == listOf("mkword")) {
             if(functionCallExpr.args[0].constValue(program)?.number==0.0) {
                 // just cast the lsb to uword
-                val cast = TypecastExpression(functionCallExpr.args[1], BaseDataType.UWORD, true, functionCallExpr.position)
+                val cast = TypecastExpression(functionCallExpr.args[1], DataType.UWORD, true, functionCallExpr.position)
                 return listOf(IAstModification.ReplaceNode(functionCallExpr, cast, parent))
             }
         }
         else if(functionCallExpr.target.nameInSource == listOf("strings", "contains")) {
-            val target = (functionCallExpr.args[0] as? IdentifierReference)?.targetVarDecl(program)
+            val target = (functionCallExpr.args[0] as? IdentifierReference)?.targetVarDecl()
             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)
@@ -711,9 +738,9 @@ class ExpressionSimplifier(private val program: Program, private val errors: IEr
                             // just use:  msb(value) as type
                             val msb = FunctionCallExpression(IdentifierReference(listOf("msb"), expr.position), mutableListOf(expr.left), expr.position)
                             return if(leftDt.isSignedWord)
-                                TypecastExpression(msb, BaseDataType.BYTE, true, expr.position)
+                                TypecastExpression(msb, DataType.BYTE, true, expr.position)
                             else
-                                TypecastExpression(msb, BaseDataType.UWORD, true, expr.position)
+                                TypecastExpression(msb, DataType.UWORD, true, expr.position)
                         }
                         else -> return null
                     }
@@ -839,14 +866,14 @@ class ExpressionSimplifier(private val program: Program, private val errors: IEr
                     // shift left by 8 bits is just a byte operation: mkword(lsb(X), 0)
                     val lsb = FunctionCallExpression(IdentifierReference(listOf("lsb"), expr.position), mutableListOf(expr.left), expr.position)
                     val mkword =  FunctionCallExpression(IdentifierReference(listOf("mkword"), expr.position), mutableListOf(lsb, NumericLiteral(BaseDataType.UBYTE, 0.0, expr.position)), expr.position)
-                    return TypecastExpression(mkword, BaseDataType.WORD, true, expr.position)
+                    return TypecastExpression(mkword, DataType.WORD, true, expr.position)
                 }
                 else if (amount > 8) {
                     // same as above but with residual shifts.
                     val lsb = FunctionCallExpression(IdentifierReference(listOf("lsb"), expr.position), mutableListOf(expr.left), expr.position)
                     val shifted = BinaryExpression(lsb, "<<", NumericLiteral.optimalInteger(amount - 8, expr.position), expr.position)
                     val mkword = FunctionCallExpression(IdentifierReference(listOf("mkword"), expr.position), mutableListOf(shifted, NumericLiteral.optimalInteger(0, expr.position)), expr.position)
-                    return TypecastExpression(mkword, BaseDataType.WORD, true, expr.position)
+                    return TypecastExpression(mkword, DataType.WORD, true, expr.position)
                 }
             }
             else -> {
@@ -887,12 +914,12 @@ class ExpressionSimplifier(private val program: Program, private val errors: IEr
                 else if(amount==8) {
                     // shift right by 8 bits is just a byte operation: msb(X) as uword
                     val msb = FunctionCallExpression(IdentifierReference(listOf("msb"), expr.position), mutableListOf(expr.left), expr.position)
-                    return TypecastExpression(msb, BaseDataType.UWORD, true, expr.position)
+                    return TypecastExpression(msb, DataType.UWORD, true, expr.position)
                 }
                 else if (amount > 8) {
                     // same as above but with residual shifts.
                     val msb = FunctionCallExpression(IdentifierReference(listOf("msb"), expr.position), mutableListOf(expr.left), expr.position)
-                    return TypecastExpression(BinaryExpression(msb, ">>", NumericLiteral.optimalInteger(amount - 8, expr.position), expr.position), BaseDataType.UWORD, true, expr.position)
+                    return TypecastExpression(BinaryExpression(msb, ">>", NumericLiteral.optimalInteger(amount - 8, expr.position), expr.position), DataType.UWORD, true, expr.position)
                 }
             }
             BaseDataType.WORD -> {
@@ -903,12 +930,12 @@ class ExpressionSimplifier(private val program: Program, private val errors: IEr
                 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, BaseDataType.BYTE, true, 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, BaseDataType.BYTE, true, expr.position)
+                    val signed = TypecastExpression(msb, DataType.BYTE, true, expr.position)
                     return BinaryExpression(signed, ">>", NumericLiteral.optimalInteger(amount - 8, expr.position), expr.position)
                 }
             }

codeOptimizers/src/prog8/optimizer/Inliner.kt

@@ -16,7 +16,7 @@ import prog8.code.target.VMTarget
 private  fun isEmptyReturn(stmt: Statement): Boolean = stmt is Return && stmt.values.isEmpty()
 
 
-// inliner potentially enables *ONE LINED* subroutines, wihtout to be inlined.
+// inliner potentially enables *ONE LINED* subroutines, without to be inlined.
 
 class Inliner(private val program: Program, private val options: CompilationOptions): AstWalker() {
 
@@ -105,7 +105,7 @@ class Inliner(private val program: Program, private val options: CompilationOpti
 
                     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.
+                        subroutine.statements.removeLastOrNull()      // get rid of the Return, to be able to inline the (single) statement preceding it.
                     }
                 }
             }
@@ -113,7 +113,7 @@ class Inliner(private val program: Program, private val options: CompilationOpti
         }
 
         private fun makeFullyScoped(identifier: IdentifierReference) {
-            identifier.targetStatement(program)?.let { target ->
+            identifier.targetStatement()?.let { target ->
                 val scoped = (target as INamedStatement).scopedName
                 val scopedIdent = IdentifierReference(scoped, identifier.position)
                 modifications += IAstModification.ReplaceNode(identifier, scopedIdent, identifier.parent)
@@ -122,7 +122,7 @@ class Inliner(private val program: Program, private val options: CompilationOpti
 
         private fun makeFullyScoped(call: FunctionCallStatement) {
             makeFullyScoped(call.target)
-            call.target.targetSubroutine(program)?.let { sub ->
+            call.target.targetSubroutine()?.let { sub ->
                 val scopedName = IdentifierReference(sub.scopedName, call.target.position)
                 val scopedArgs = makeScopedArgs(call.args)
                 if(scopedArgs.any()) {
@@ -134,7 +134,7 @@ class Inliner(private val program: Program, private val options: CompilationOpti
 
         private fun makeFullyScoped(call: FunctionCallExpression) {
             makeFullyScoped(call.target)
-            call.target.targetSubroutine(program)?.let { sub ->
+            call.target.targetSubroutine()?.let { sub ->
                 val scopedName = IdentifierReference(sub.scopedName, call.target.position)
                 val scopedArgs = makeScopedArgs(call.args)
                 if(scopedArgs.any()) {
@@ -149,7 +149,7 @@ class Inliner(private val program: Program, private val options: CompilationOpti
                 when (it) {
                     is NumericLiteral -> it.copy()
                     is IdentifierReference -> {
-                        val target = it.targetStatement(program) ?: return emptyList()
+                        val target = it.targetStatement() ?: return emptyList()
                         val scoped = (target as INamedStatement).scopedName
                         IdentifierReference(scoped, it.position)
                     }
@@ -205,7 +205,7 @@ class Inliner(private val program: Program, private val options: CompilationOpti
     }
 
     override fun after(functionCallStatement: FunctionCallStatement, parent: Node): Iterable<IAstModification>  {
-        val sub = functionCallStatement.target.targetStatement(program) as? Subroutine
+        val sub = functionCallStatement.target.targetStatement(program.builtinFunctions) as? Subroutine
         return if(sub==null || !canInline(sub, functionCallStatement))
             noModifications
         else
@@ -213,7 +213,7 @@ class Inliner(private val program: Program, private val options: CompilationOpti
     }
 
     override fun before(functionCallExpr: FunctionCallExpression, parent: Node): Iterable<IAstModification> {
-        val sub = functionCallExpr.target.targetStatement(program) as? Subroutine
+        val sub = functionCallExpr.target.targetStatement(program.builtinFunctions) as? Subroutine
         if(sub!=null && sub.inline && sub.parameters.isEmpty() && canInline(sub, functionCallExpr)) {
             require(sub.statements.size == 1 || (sub.statements.size == 2 && isEmptyReturn(sub.statements[1]))) {
                 "invalid inline sub at ${sub.position}"
@@ -249,7 +249,7 @@ class Inliner(private val program: Program, private val options: CompilationOpti
             val stmt = sub.statements.single()
             if (stmt is IFunctionCall) {
                 val existing = (fcall as Node).definingScope.lookup(stmt.target.nameInSource.take(1))
-                return existing !is VarDecl
+                return existing !is VarDecl && existing !is StructFieldRef
             }
         }
         return true

codeOptimizers/src/prog8/optimizer/StatementOptimizer.kt

@@ -19,7 +19,7 @@ class StatementOptimizer(private val program: Program,
             val functionName = functionCallStatement.target.nameInSource[0]
             if (functionName in functions.purefunctionNames) {
                 if("ignore_unused" !in parent.definingBlock.options())
-                    errors.info("statement has no effect (function return value is discarded)", functionCallStatement.position)
+                    errors.warn("statement has no effect (function return value is discarded)", functionCallStatement.position)
                 return listOf(IAstModification.Remove(functionCallStatement, parent as IStatementContainer))
             }
         }
@@ -29,12 +29,19 @@ 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) {
-                if(arg.arrayIndex==null) arg.identifier else null
+                if(arg.arrayIndex==null) {
+                    if(arg.identifier!=null)
+                        arg.identifier
+                    else
+                        null // struct can't have string fields so nothing to look at here
+                } else {
+                    null
+                }
             } else {
                 arg as? IdentifierReference
             }
-            if(stringVar!=null && stringVar.wasStringLiteral(program)) {
-                val string = stringVar.targetVarDecl(program)?.value as? StringLiteral
+            if(stringVar!=null && stringVar.wasStringLiteral()) {
+                val string = stringVar.targetVarDecl()?.value as? StringLiteral
                 if(string!=null) {
                     val pos = functionCallStatement.position
                     if (string.value.length == 1) {
@@ -82,12 +89,11 @@ class StatementOptimizer(private val program: Program,
         // empty true part? switch with the else part
         if(ifElse.truepart.isEmpty() && ifElse.elsepart.isNotEmpty()) {
             val invertedCondition = invertCondition(ifElse.condition, program)
-            val emptyscope = AnonymousScope(mutableListOf(), ifElse.elsepart.position)
             val truepart = AnonymousScope(ifElse.elsepart.statements, ifElse.truepart.position)
             return listOf(
                     IAstModification.ReplaceNode(ifElse.condition, invertedCondition, ifElse),
                     IAstModification.ReplaceNode(ifElse.truepart, truepart, ifElse),
-                    IAstModification.ReplaceNode(ifElse.elsepart, emptyscope, ifElse)
+                    IAstModification.ReplaceNode(ifElse.elsepart, AnonymousScope.empty(), ifElse)
             )
         }
 
@@ -106,7 +112,7 @@ class StatementOptimizer(private val program: Program,
             if(ifElse.truepart.statements.singleOrNull() is Return) {
                 val elsePart = AnonymousScope(ifElse.elsepart.statements, ifElse.elsepart.position)
                 return listOf(
-                    IAstModification.ReplaceNode(ifElse.elsepart, AnonymousScope(mutableListOf(), ifElse.elsepart.position), ifElse),
+                    IAstModification.ReplaceNode(ifElse.elsepart, AnonymousScope.empty(), ifElse),
                     IAstModification.InsertAfter(ifElse, elsePart, parent as IStatementContainer)
                 )
             }
@@ -146,13 +152,13 @@ class StatementOptimizer(private val program: Program,
             if (range.size() == 1) {
                 // for loop over a (constant) range of just a single value-- optimize the loop away
                 // loopvar/reg = range value , follow by block
-                val scope = AnonymousScope(mutableListOf(), forLoop.position)
-                scope.statements.add(Assignment(AssignTarget(forLoop.loopVar, null, null, null, false, forLoop.position), range.from, AssignmentOrigin.OPTIMIZER, forLoop.position))
+                val scope = AnonymousScope.empty(forLoop.position)
+                scope.statements.add(Assignment(AssignTarget(forLoop.loopVar, null, null, null, false, position=forLoop.position), range.from, AssignmentOrigin.OPTIMIZER, forLoop.position))
                 scope.statements.addAll(forLoop.body.statements)
                 return listOf(IAstModification.ReplaceNode(forLoop, scope, parent))
             }
         }
-        val iterable = (forLoop.iterable as? IdentifierReference)?.targetVarDecl(program)
+        val iterable = (forLoop.iterable as? IdentifierReference)?.targetVarDecl()
         if(iterable!=null) {
             if(iterable.datatype.isString) {
                 val sv = iterable.value as StringLiteral
@@ -161,8 +167,8 @@ class StatementOptimizer(private val program: Program,
                     // loop over string of length 1 -> just assign the single character
                     val character = options.compTarget.encodeString(sv.value, sv.encoding)[0]
                     val byte = NumericLiteral(BaseDataType.UBYTE, character.toDouble(), iterable.position)
-                    val scope = AnonymousScope(mutableListOf(), forLoop.position)
-                    scope.statements.add(Assignment(AssignTarget(forLoop.loopVar, null, null, null, false, forLoop.position), byte, AssignmentOrigin.OPTIMIZER, forLoop.position))
+                    val scope = AnonymousScope.empty(forLoop.position)
+                    scope.statements.add(Assignment(AssignTarget(forLoop.loopVar, null, null, null, false, position=forLoop.position), byte, AssignmentOrigin.OPTIMIZER, forLoop.position))
                     scope.statements.addAll(forLoop.body.statements)
                     return listOf(IAstModification.ReplaceNode(forLoop, scope, parent))
                 }
@@ -173,9 +179,9 @@ class StatementOptimizer(private val program: Program,
                     // loop over array of length 1 -> just assign the single value
                     val av = (iterable.value as ArrayLiteral).value[0].constValue(program)?.number
                     if(av!=null) {
-                        val scope = AnonymousScope(mutableListOf(), forLoop.position)
+                        val scope = AnonymousScope.empty(forLoop.position)
                         scope.statements.add(Assignment(
-                                AssignTarget(forLoop.loopVar, null, null, null, false, forLoop.position), NumericLiteral.optimalInteger(av.toInt(), iterable.position),
+                                AssignTarget(forLoop.loopVar, null, null, null, false, position = forLoop.position), NumericLiteral.optimalInteger(av.toInt(), iterable.position),
                                 AssignmentOrigin.OPTIMIZER, forLoop.position))
                         scope.statements.addAll(forLoop.body.statements)
                         return listOf(IAstModification.ReplaceNode(forLoop, scope, parent))
@@ -342,6 +348,39 @@ class StatementOptimizer(private val program: Program,
                 }
 
             }
+
+            // pointer arithmetic for 6502 target
+            if (options.compTarget.cpu != CpuType.VIRTUAL) {
+                if(bexpr.operator=="+" && !bexpr.right.isSimple && !assignment.isAugmentable) {
+                    if(targetIDt.isUnsignedWord || targetIDt.getOrUndef().isPointerToByte) {
+                        val leftDt = bexpr.left.inferType(program).getOrUndef()
+                        val rightDt = bexpr.right.inferType(program).getOrUndef()
+
+                        fun setSizedValue(a: Assignment, value: Expression, size: Int) {
+                            val sized = BinaryExpression(value, "*", NumericLiteral.optimalInteger(size, value.position), value.position)
+                            a.value = sized
+                            sized.linkParents(a)
+                        }
+
+                        if (leftDt.isPointer && !leftDt.isPointerToByte) {
+                            // uword x = pointer + value    -->  x=value * sizeof ,  x += pointer
+                            val size = leftDt.size(options.compTarget)
+                            setSizedValue(assignment, bexpr.right, size)
+                            val pointerAdd = BinaryExpression(assignment.target.toExpression(), bexpr.operator, bexpr.left, bexpr.position)
+                            val a2 = Assignment(assignment.target.copy(), pointerAdd, assignment.origin, assignment.position)
+                            return listOf(IAstModification.InsertAfter(assignment, a2, parent as IStatementContainer))
+                        } else if (rightDt.isPointer && !rightDt.isPointerToByte) {
+                            // uword x = value + pointer  -->  x=value * sizeof,  x += pointer
+                            val size = rightDt.size(options.compTarget)
+                            setSizedValue(assignment, bexpr.left, size)
+                            assignment.linkParents(parent)
+                            val pointerAdd = BinaryExpression(assignment.target.toExpression(), bexpr.operator, bexpr.right, bexpr.position)
+                            val a2 = Assignment(assignment.target.copy(), pointerAdd, assignment.origin, assignment.position)
+                            return listOf(IAstModification.InsertAfter(assignment, a2, parent as IStatementContainer))
+                        }
+                    }
+                }
+            }
         }
 
         // word = lsb(word)
@@ -466,7 +505,7 @@ class StatementOptimizer(private val program: Program,
         return IfElse(
             compare,
             AnonymousScope(mutableListOf(assign), position),
-            AnonymousScope(mutableListOf(), position),
+            AnonymousScope.empty(),
             position
         )
     }
@@ -501,6 +540,27 @@ class StatementOptimizer(private val program: Program,
             }
         }
 
+        if(whenStmt.betterAsOnGoto(program, options)) {
+            // rewrite when into a on..goto , which is faster and also smaller for ~5+ cases
+            var elseJump: Jump? = null
+            val jumps = mutableListOf<Pair<Int, Jump>>()
+            whenStmt.choices.forEach { choice ->
+                if(choice.values==null) {
+                    elseJump = choice.statements.statements.single() as Jump
+                } else {
+                    choice.values!!.forEach { value ->
+                        jumps.add(value.constValue(program)!!.number.toInt() to choice.statements.statements.single() as Jump)
+                    }
+                }
+            }
+
+            val jumpLabels = jumps.sortedBy { it.first }.map { it.second.target as IdentifierReference }
+
+            val elsePart = if(elseJump==null) null else AnonymousScope(mutableListOf(elseJump), elseJump.position)
+            val onGoto = OnGoto(false, whenStmt.condition, jumpLabels, elsePart, whenStmt.position)
+            return listOf(IAstModification.ReplaceNode(whenStmt, onGoto, parent))
+        }
+
         return noModifications
     }
 

codeOptimizers/src/prog8/optimizer/UnusedCodeRemover.kt

@@ -8,9 +8,9 @@ import prog8.ast.expressions.TypecastExpression
 import prog8.ast.statements.*
 import prog8.ast.walk.AstWalker
 import prog8.ast.walk.IAstModification
+import prog8.code.INTERNED_STRINGS_MODULENAME
 import prog8.code.core.ICompilationTarget
 import prog8.code.core.IErrorReporter
-import prog8.code.INTERNED_STRINGS_MODULENAME
 import prog8.compiler.CallGraph
 
 
@@ -27,10 +27,10 @@ class UnusedCodeRemover(private val program: Program,
 
         program.allBlocks.singleOrNull { it.name=="sys" } ?.let {
             val subroutines = it.statements.filterIsInstance<Subroutine>()
-            val push = subroutines.single { it.name == "push" }
-            val pushw = subroutines.single { it.name == "pushw" }
-            val pop = subroutines.single { it.name == "pop" }
-            val popw = subroutines.single { it.name == "popw" }
+            val push = subroutines.single { s -> s.name == "push" }
+            val pushw = subroutines.single { s -> s.name == "pushw" }
+            val pop = subroutines.single { s -> s.name == "pop" }
+            val popw = subroutines.single { s -> s.name == "popw" }
             neverRemoveSubroutines.add(push)
             neverRemoveSubroutines.add(pushw)
             neverRemoveSubroutines.add(pop)
@@ -39,8 +39,8 @@ class UnusedCodeRemover(private val program: Program,
 
         program.allBlocks.singleOrNull { it.name=="floats" } ?.let {
             val subroutines = it.statements.filterIsInstance<Subroutine>()
-            val push = subroutines.single { it.name == "push" }
-            val pop = subroutines.single { it.name == "pop" }
+            val push = subroutines.single { s -> s.name == "push" }
+            val pop = subroutines.single { s -> s.name == "pop" }
             neverRemoveSubroutines.add(push)
             neverRemoveSubroutines.add(pop)
         }
@@ -181,14 +181,20 @@ class UnusedCodeRemover(private val program: Program,
                                         val declIndex = (parent as IStatementContainer).statements.indexOf(decl)
                                         val singleUseIndex = (parent as IStatementContainer).statements.indexOf(singleUse.parent)
                                         if(declIndex==singleUseIndex-1) {
-                                            if("ignore_unused" !in decl.definingBlock.options())
-                                                errors.info("replaced unused variable '${decl.name}' with void call, maybe this can be removed altogether", decl.position)
-                                            val fcall = assignment.value as IFunctionCall
-                                            val voidCall = FunctionCallStatement(fcall.target, fcall.args, true, fcall.position)
-                                            return listOf(
-                                                IAstModification.ReplaceNode(decl, voidCall, parent),
-                                                IAstModification.Remove(assignment, assignment.parent as IStatementContainer)
-                                            )
+                                            val callStruct = (assignment.value as IFunctionCall).target.targetStructDecl()
+                                            if(callStruct!=null) {
+                                                // don't turn a struct instance allocation call to a void call, instead, remove everything
+                                                return listOf(IAstModification.Remove(assignment, assignment.parent as IStatementContainer))
+                                            } else {
+                                                if("ignore_unused" !in decl.definingBlock.options())
+                                                    errors.info("replaced unused variable '${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 {

compiler/build.gradle.kts

@@ -1,5 +1,3 @@
-import org.jetbrains.kotlin.gradle.dsl.JvmTarget
-
 plugins {
     id("application")
     kotlin("jvm")
@@ -18,18 +16,15 @@ dependencies {
     implementation(project(":codeGenExperimental"))
     implementation(project(":virtualmachine"))
     // implementation(project(":beanshell"))
-    implementation("org.antlr:antlr4-runtime:4.13.2")
     // implementation("org.jetbrains.kotlin:kotlin-stdlib-jdk8")
     // implementation("org.jetbrains.kotlin:kotlin-reflect")
     implementation("org.jetbrains.kotlinx:kotlinx-cli:0.3.6")
-    implementation("com.michael-bull.kotlin-result:kotlin-result-jvm:2.0.1")
+    implementation("com.michael-bull.kotlin-result:kotlin-result-jvm:2.1.0")
 
     testImplementation(project(":codeCore"))
     testImplementation(project(":intermediate"))
     testImplementation("io.kotest:kotest-runner-junit5-jvm:5.9.1")
     testImplementation("io.kotest:kotest-framework-datatest:5.9.1")
-    testImplementation("org.junit.jupiter:junit-jupiter:5.9.1")
-    testRuntimeOnly("org.junit.platform:junit-platform-launcher")
 }
 
 configurations.all {
@@ -83,6 +78,8 @@ gversion {
     classPackage = "prog8.buildversion"
     className = "Version"
     language = "kotlin"
+    debug = false
+    annotate = true
 }
 
 tasks.build {

compiler/compiler.iml

@@ -13,9 +13,7 @@
     <orderEntry type="library" name="KotlinJavaRuntime" level="project" />
     <orderEntry type="library" name="jetbrains.kotlinx.cli.jvm" level="project" />
     <orderEntry type="library" name="michael.bull.kotlin.result.jvm" level="project" />
-    <orderEntry type="library" name="io.kotest.assertions.core.jvm" level="project" />
     <orderEntry type="library" name="io.kotest.runner.junit5.jvm" level="project" />
-    <orderEntry type="library" name="io.kotest.framework.datatest" level="project" />
     <orderEntry type="module" module-name="codeCore" />
     <orderEntry type="module" module-name="simpleAst" />
     <orderEntry type="module" module-name="compilerAst" />
@@ -25,6 +23,6 @@
     <orderEntry type="module" module-name="codeGenIntermediate" />
     <orderEntry type="module" module-name="virtualmachine" />
     <orderEntry type="module" module-name="intermediate" />
-    <orderEntry type="library" name="antlr.antlr4" level="project" />
+    <orderEntry type="library" name="io.kotest.framework.datatest" level="project" />
   </component>
 </module>

compiler/res/prog8lib/c128/syslib.p8

@@ -317,10 +317,25 @@ c128 {
     &ubyte  VM4     = $0A2F         ; starting page for VDC attribute mem
 
 
-; TODO c128 a bunch of kernal routines are missing here that are specific to the c128
-
-extsub $FF6E = JSRFAR()
-extsub $FF68 = SETBNK(ubyte databank @A, ubyte filenamebank @X)
+extsub $FF47 = SPIN_SPOUT() clobbers(A)                         ; set up serial bus for fast communications mode
+extsub $FF4A = CLOSE_ALL(ubyte device @X)  clobbers(X)          ; close all channels to specific device
+extsub $FF4D = C64_MODE()                                       ; restart machine in C64 mode (does not return)
+extsub $FF50 = DMA_CALL(ubyte bank @X, ubyte command @Y) clobbers(A,X) ; send a command to a DMA device
+extsub $FF53 = BOOT_CALL(ubyte device @X, ubyte drive @A) clobbers(A,X,Y) ; try to autoboot the given disk
+extsub $FF56 = PHOENIX() clobbers(A,X,Y)                        ; search for and autostart ROMs, cartridges, then default disk
+extsub $FF59 = LKUPLA(ubyte lfn @A) -> bool @Pc, ubyte @X       ; look up logical file number to see if it's open; returns device
+extsub $FF5C = LKUPSA(ubyte sa @Y) -> bool @Pc, ubyte @A, ubyte @X ; look up secondary address to see if it's in use; returns lfn and device
+extsub $FF5F = SWAPPER() clobbers(A,X,Y)                        ; swap active screen (between 40- and 80-column)
+extsub $FF62 = DLCHR() clobbers(A,X,Y)                          ; copy character ROM into VDC video RAM
+extsub $FF65 = PFKEY(ubyte zpaddr @A, ubyte key @X, ubyte length @Y) ; redefine programmable function key (string descriptor in zp, addr in A)
+extsub $FF68 = SETBNK(ubyte data_bank @A, ubyte filename_bank @X) ; set memory bank for load/save
+extsub $FF6B = GETCFG(ubyte bank @X) -> ubyte @A                ; translate bank number to MMU configuration register value
+extsub $FF6E = JSRFAR() clobbers(A,X)                           ; call routine in another bank (parameters set in zero page addresses 2-8)
+extsub $FF71 = JMPFAR() clobbers(A,X)                           ; jump without return to another bank (parameters set as for JSRFAR)
+extsub $FF74 = INDFET(ubyte zpaddr @A, ubyte bank @X, ubyte offset @Y) clobbers(X) -> ubyte @A ; fetch byte from another bank (address in zp, ptr in A)
+extsub $FF77 = INDSTA(ubyte value @A, ubyte bank @X, ubyte offset @Y) clobbers(X) ; store byte to another bank (address in zp, ptr in $02b9)
+extsub $FF7A = INDCMP(ubyte value @A, ubyte bank @X, ubyte offset @Y) clobbers(X) -> bool @Pz, bool @Pc, bool @Pv; compare byte in another bank (address in zp, ptr in $02c8)
+extsub $FF7D = PRIMM()                                          ; print immediate string
 
 
 ; ---- C128 specific system utility routines: ----
@@ -419,12 +434,14 @@ sys {
 
     const ubyte target = 128         ;  compilation target specifier.  255=virtual, 128=C128, 64=C64, 32=PET, 16=CommanderX16, 8=atari800XL, 7=Neo6502
 
-    const ubyte SIZEOF_BOOL  = 1
-    const ubyte SIZEOF_BYTE  = 1
-    const ubyte SIZEOF_UBYTE = 1
-    const ubyte SIZEOF_WORD  = 2
-    const ubyte SIZEOF_UWORD = 2
-    const ubyte SIZEOF_FLOAT = 5
+    const ubyte SIZEOF_BOOL  = sizeof(bool)
+    const ubyte SIZEOF_BYTE  = sizeof(byte)
+    const ubyte SIZEOF_UBYTE = sizeof(ubyte)
+    const ubyte SIZEOF_WORD  = sizeof(word)
+    const ubyte SIZEOF_UWORD = sizeof(uword)
+    const ubyte SIZEOF_LONG  = sizeof(long)
+    const ubyte SIZEOF_POINTER = sizeof(&sys.wait)
+    const ubyte SIZEOF_FLOAT = sizeof(float)
     const byte  MIN_BYTE     = -128
     const byte  MAX_BYTE     = 127
     const ubyte MIN_UBYTE    = 0
@@ -663,7 +680,7 @@ _loop       lda  P8ZP_SCRATCH_W1
         }}
     }
 
-    asmsub internal_stringcopy(uword source @R0, uword target @AY) clobbers (A,Y) {
+    asmsub internal_stringcopy(str source @R0, str target @AY) clobbers (A,Y) {
         ; Called when the compiler wants to assign a string value to another string.
         %asm {{
 		sta  P8ZP_SCRATCH_W1
@@ -946,6 +963,18 @@ _no_msb_size
         }}
     }
 
+    asmsub get_as_returnaddress(uword address @XY) -> uword @AX {
+        %asm {{
+            ; return the address like JSR would push onto the stack:  address-1,  MSB first then LSB
+            cpx  #0
+            bne  +
+            dey
++           dex
+            tya
+            rts
+        }}
+    }
+
     inline asmsub pop() -> ubyte @A {
         %asm {{
             pla
@@ -984,6 +1013,7 @@ cx16 {
     &uword r14 = $1bfc
     &uword r15 = $1bfe
 
+    ; signed word versions
     &word r0s  = $1be0
     &word r1s  = $1be2
     &word r2s  = $1be4
@@ -1001,6 +1031,7 @@ cx16 {
     &word r14s = $1bfc
     &word r15s = $1bfe
 
+    ; ubyte versions (low and high bytes)
     &ubyte r0L  = $1be0
     &ubyte r1L  = $1be2
     &ubyte r2L  = $1be4
@@ -1035,6 +1066,7 @@ cx16 {
     &ubyte r14H = $1bfd
     &ubyte r15H = $1bff
 
+    ; signed byte versions (low and high bytes)
     &byte r0sL  = $1be0
     &byte r1sL  = $1be2
     &byte r2sL  = $1be4
@@ -1069,6 +1101,42 @@ cx16 {
     &byte r14sH = $1bfd
     &byte r15sH = $1bff
 
+    ; boolean versions (low and high bytes)
+    &bool r0bL  = $1be0
+    &bool r1bL  = $1be2
+    &bool r2bL  = $1be4
+    &bool r3bL  = $1be6
+    &bool r4bL  = $1be8
+    &bool r5bL  = $1bea
+    &bool r6bL  = $1bec
+    &bool r7bL  = $1bee
+    &bool r8bL  = $1bf0
+    &bool r9bL  = $1bf2
+    &bool r10bL = $1bf4
+    &bool r11bL = $1bf6
+    &bool r12bL = $1bf8
+    &bool r13bL = $1bfa
+    &bool r14bL = $1bfc
+    &bool r15bL = $1bfe
+
+    &bool r0bH  = $1be1
+    &bool r1bH  = $1be3
+    &bool r2bH  = $1be5
+    &bool r3bH  = $1be7
+    &bool r4bH  = $1be9
+    &bool r5bH  = $1beb
+    &bool r6bH  = $1bed
+    &bool r7bH  = $1bef
+    &bool r8bH  = $1bf1
+    &bool r9bH  = $1bf3
+    &bool r10bH = $1bf5
+    &bool r11bH = $1bf7
+    &bool r12bH = $1bf9
+    &bool r13bH = $1bfb
+    &bool r14bH = $1bfd
+    &bool r15bH = $1bff
+
+
     asmsub save_virtual_registers() clobbers(A,Y) {
         %asm {{
             ldy  #31

compiler/res/prog8lib/c128/textio.p8

@@ -16,26 +16,6 @@ const ubyte DEFAULT_HEIGHT = 25
 extsub $FFD2 = chrout(ubyte character @ A)    ; for consistency. You can also use cbm.CHROUT directly ofcourse. Note: takes a PETSCII encoded character.
 
 
-sub  clear_screen() {
-    chrout(147)
-}
-
-sub  cls() {
-    chrout(147)
-}
-
-sub home() {
-    chrout(19)
-}
-
-sub nl() {
-    chrout('\n')
-}
-
-sub spc() {
-    chrout(' ')
-}
-
 sub bell() {
     chrout(7)
 }

compiler/res/prog8lib/c64/floats.asm

@@ -149,6 +149,29 @@ copy_float	.proc
 		rts
 		.pend
 
+copy_float2	.proc
+		; -- copies the 5 bytes of the mflt value pointed to by P8ZP_SCRATCH_W2,
+		;    into the 5 bytes pointed to by A/Y.  Clobbers A,Y.
+		sta  P8ZP_SCRATCH_W1
+		sty  P8ZP_SCRATCH_W1+1
+		ldy  #0
+		lda  (P8ZP_SCRATCH_W2),y
+		sta  (P8ZP_SCRATCH_W1),y
+		iny
+		lda  (P8ZP_SCRATCH_W2),y
+		sta  (P8ZP_SCRATCH_W1),y
+		iny
+		lda  (P8ZP_SCRATCH_W2),y
+		sta  (P8ZP_SCRATCH_W1),y
+		iny
+		lda  (P8ZP_SCRATCH_W2),y
+		sta  (P8ZP_SCRATCH_W1),y
+		iny
+		lda  (P8ZP_SCRATCH_W2),y
+		sta  (P8ZP_SCRATCH_W1),y
+		rts
+		.pend
+
 inc_var_f	.proc
 		; -- add 1 to float pointed to by A/Y
 		;    clobbers X

compiler/res/prog8lib/c64/graphics.p8

@@ -376,7 +376,7 @@ hline_filled_right   .byte  0, %10000000, %11000000, %11100000, %11110000, %1111
 _ormask     .byte 128, 64, 32, 16, 8, 4, 2, 1
 
 ; note: this can be even faster if we also have a 320 word x-lookup table, but hey, that's a lot of memory.
-; see http://codebase64.org/doku.php?id=base:various_techniques_to_calculate_adresses_fast_common_screen_formats_for_pixel_graphics
+; see https://codebase64.net/doku.php?id=base:various_techniques_to_calculate_adresses_fast_common_screen_formats_for_pixel_graphics
 ; the y lookup tables encodes this formula:  BITMAP_ADDRESS + 320*(py>>3) + (py & 7)    (y from 0..199)
 ; We use the 64tass syntax for range expressions to calculate this table on assembly time.
 

compiler/res/prog8lib/c64/syslib.p8

@@ -57,7 +57,7 @@ cbm {
 
 ; ---- CBM ROM kernal routines (C64 addresses) ----
 
-extsub $AB1E = STROUT(uword strptr @ AY) clobbers(A, X, Y)      ; print null-terminated string (use txt.print instead)
+extsub $AB1E = STROUT(str strptr @ AY) clobbers(A, X, Y)      ; print null-terminated string (use txt.print instead)
 extsub $E544 = CLEARSCR() clobbers(A,X,Y)                       ; clear the screen
 extsub $E566 = HOMECRSR() clobbers(A,X,Y)                       ; cursor to top left of screen
 extsub $EA31 = IRQDFRT() clobbers(A,X,Y)                        ; default IRQ routine
@@ -439,12 +439,14 @@ sys {
 
     const ubyte target = 64         ;  compilation target specifier.  255=virtual, 128=C128, 64=C64, 32=PET, 16=CommanderX16, 8=atari800XL, 7=Neo6502
 
-    const ubyte SIZEOF_BOOL  = 1
-    const ubyte SIZEOF_BYTE  = 1
-    const ubyte SIZEOF_UBYTE = 1
-    const ubyte SIZEOF_WORD  = 2
-    const ubyte SIZEOF_UWORD = 2
-    const ubyte SIZEOF_FLOAT = 5
+    const ubyte SIZEOF_BOOL  = sizeof(bool)
+    const ubyte SIZEOF_BYTE  = sizeof(byte)
+    const ubyte SIZEOF_UBYTE = sizeof(ubyte)
+    const ubyte SIZEOF_WORD  = sizeof(word)
+    const ubyte SIZEOF_UWORD = sizeof(uword)
+    const ubyte SIZEOF_LONG  = sizeof(long)
+    const ubyte SIZEOF_POINTER = sizeof(&sys.wait)
+    const ubyte SIZEOF_FLOAT = sizeof(float)
     const byte  MIN_BYTE     = -128
     const byte  MAX_BYTE     = 127
     const ubyte MIN_UBYTE    = 0
@@ -685,7 +687,7 @@ _loop       lda  P8ZP_SCRATCH_W1
         }}
     }
 
-    asmsub internal_stringcopy(uword source @R0, uword target @AY) clobbers (A,Y) {
+    asmsub internal_stringcopy(str source @R0, str target @AY) clobbers (A,Y) {
         ; Called when the compiler wants to assign a string value to another string.
         %asm {{
 		sta  P8ZP_SCRATCH_W1
@@ -968,6 +970,18 @@ _no_msb_size
         }}
     }
 
+    asmsub get_as_returnaddress(uword address @XY) -> uword @AX {
+        %asm {{
+            ; return the address like JSR would push onto the stack:  address-1,  MSB first then LSB
+            cpx  #0
+            bne  +
+            dey
++           dex
+            tya
+            rts
+        }}
+    }
+
     inline asmsub pop() -> ubyte @A {
         %asm {{
             pla
@@ -1006,6 +1020,7 @@ cx16 {
     &uword r14 = $cffc
     &uword r15 = $cffe
 
+    ; signed word versions
     &word r0s  = $cfe0
     &word r1s  = $cfe2
     &word r2s  = $cfe4
@@ -1023,6 +1038,7 @@ cx16 {
     &word r14s = $cffc
     &word r15s = $cffe
 
+    ; ubyte versions (low and high bytes)
     &ubyte r0L  = $cfe0
     &ubyte r1L  = $cfe2
     &ubyte r2L  = $cfe4
@@ -1057,6 +1073,7 @@ cx16 {
     &ubyte r14H = $cffd
     &ubyte r15H = $cfff
 
+    ; signed byte versions (low and high bytes)
     &byte r0sL  = $cfe0
     &byte r1sL  = $cfe2
     &byte r2sL  = $cfe4
@@ -1091,6 +1108,42 @@ cx16 {
     &byte r14sH = $cffd
     &byte r15sH = $cfff
 
+    ; boolean versions
+    &bool r0bL  = $cfe0
+    &bool r1bL  = $cfe2
+    &bool r2bL  = $cfe4
+    &bool r3bL  = $cfe6
+    &bool r4bL  = $cfe8
+    &bool r5bL  = $cfea
+    &bool r6bL  = $cfec
+    &bool r7bL  = $cfee
+    &bool r8bL  = $cff0
+    &bool r9bL  = $cff2
+    &bool r10bL = $cff4
+    &bool r11bL = $cff6
+    &bool r12bL = $cff8
+    &bool r13bL = $cffa
+    &bool r14bL = $cffc
+    &bool r15bL = $cffe
+
+    &bool r0bH  = $cfe1
+    &bool r1bH  = $cfe3
+    &bool r2bH  = $cfe5
+    &bool r3bH  = $cfe7
+    &bool r4bH  = $cfe9
+    &bool r5bH  = $cfeb
+    &bool r6bH  = $cfed
+    &bool r7bH  = $cfef
+    &bool r8bH  = $cff1
+    &bool r9bH  = $cff3
+    &bool r10bH = $cff5
+    &bool r11bH = $cff7
+    &bool r12bH = $cff9
+    &bool r13bH = $cffb
+    &bool r14bH = $cffd
+    &bool r15bH = $cfff
+
+
     asmsub save_virtual_registers() clobbers(A,Y) {
         %asm {{
             ldy  #31

compiler/res/prog8lib/c64/textio.p8

@@ -15,25 +15,6 @@ const ubyte DEFAULT_HEIGHT = 25
 
 extsub $FFD2 = chrout(ubyte character @ A)    ; for consistency. You can also use cbm.CHROUT directly ofcourse. Note: takes a PETSCII encoded character.
 
-sub  clear_screen() {
-    chrout(147)
-}
-
-sub  cls() {
-    chrout(147)
-}
-
-sub home() {
-    chrout(19)
-}
-
-sub nl() {
-    chrout('\n')
-}
-
-sub spc() {
-    chrout(' ')
-}
 
 sub bell() {
     ; beep

compiler/res/prog8lib/coroutines.p8

@@ -28,12 +28,20 @@
 ;   that routine can for instance call current() (or just look at the active_task variable) to get the id of the next task to execute.
 ;   It has then to return a boolean: true=next task is to be executed, false=skip the task this time.
 ; - in tasks: call yield() to pass control to the next task. Use the returned userdata value to do different things.
+;   For now, you MUST call yield() only from the actual subroutine that has been registered as a task!
+;   (this is because otherwise the cpu call stack gets messed up and an RTS in task1 could suddenly pop a return address belonging to another tasks' call frame)
 ; - call current() to get the current task id.
 ; - call kill(taskid) to kill a task by id.
 ; - call killall() to kill all tasks.
 ; - IMPORTANT:  if you add the same subroutine multiple times, IT CANNOT DEPEND ON ANY LOCAL VARIABLES OR R0-R15 TO KEEP STATE. NOT EVEN REPEAT LOOP COUNTERS.
 ;   Those are all shared in the different tasks! You HAVE to use a mechanism around the userdata value (pointer?) to keep separate state elsewhere!
 ; - IMPORTANT:  ``defer`` cannot be used inside a coroutine that is reused for multiple tasks!!!
+;
+; TIP: HOW TO WAIT without BLOCKING other coroutines?
+; Make sure you call yield() in the waiting loop, for example:
+;            uword timer = cbm.RDTIM16() + 60
+;            while cbm.RDTIM16() != timer
+;                void coroutines.yield()
 
 coroutines {
     %option ignore_unused
@@ -41,19 +49,17 @@ coroutines {
     const ubyte MAX_TASKS = 64
     uword[MAX_TASKS] tasklist
     uword[MAX_TASKS] userdatas
-    uword[MAX_TASKS] returnaddresses
     ubyte active_task
     uword supervisor
 
-    sub add(uword taskaddress, uword userdata) -> ubyte {
+    sub add(uword @nozp taskaddress, uword @nozp userdata) -> ubyte {
         ; find the next empty slot in the tasklist and stick it there
         ; returns the task id of the new task, or 255 if there was no space for more tasks. 0 is a valid task id!
         ; also returns the success in the Carry flag (carry set=success, carry clear = task was not added)
         for cx16.r0L in 0 to len(tasklist)-1 {
             if tasklist[cx16.r0L] == 0 {
-                tasklist[cx16.r0L] = taskaddress
+                tasklist[cx16.r0L] = sys.get_as_returnaddress(taskaddress)
                 userdatas[cx16.r0L] = userdata
-                returnaddresses[cx16.r0L] = 0
                 sys.set_carry()
                 return cx16.r0L
             }
@@ -70,57 +76,48 @@ coroutines {
         }
     }
 
-    sub run(uword supervisor_routine) {
+    sub run(uword @nozp supervisor_routine) {
         supervisor = supervisor_routine
         for active_task in 0 to len(tasklist)-1 {
             if tasklist[active_task]!=0 {
                 ; activate the termination handler and start the first task
                 ; note: cannot use pushw() because JSR doesn't push the return address in the same way
                 sys.push_returnaddress(&termination)
-                goto tasklist[active_task]
+                sys.pushw(tasklist[active_task])
+                return
             }
         }
     }
 
     sub yield() -> uword {
-        ; Store the return address of the yielding task,
-        ; and continue with the next one instead (round-robin)
-        ; Returns the associated userdata value
-        uword task_start, task_continue
-        returnaddresses[active_task] = sys.popw()
+        ; Store the return address of the yielding task, and continue with the next one instead (round-robin)
+        ; Returns the associated userdata value.
+        ; NOTE: CAN ONLY BE CALLED FROM THE SCOPE OF THE SUBROUTINE THAT HAS BEEN REGISTERED AS THE TASK!
+        uword task_return_address
+        tasklist[active_task] = sys.popw()
 
-resume_with_next_task:
+skip_task:
         if not next_task() {
             void sys.popw()     ; remove return to the termination handler
-            return 0   ; exiting here will now actually return from the start() call back to the calling program :)
+            return 0   ; exiting here will now actually return back to the calling program that called run()
         }
 
-        if supervisor!=0 {
+        if supervisor!=0
             if lsb(call(supervisor))==0
-                goto resume_with_next_task
-        }
+                goto skip_task
 
-        if task_continue==0 {
-            ; fetch start address of next task.
-            ; address on the stack must be pushed in reverse byte order
-            ; also, subtract 1 from the start address because JSR pushes returnaddress minus 1
-            ; note: cannot use pushw() because JSR doesn't push the return address in the same way
-            sys.push_returnaddress(task_start)
-        } else
-            sys.pushw(task_continue)
-
-        ; returning from yield then continues with the next coroutine
+        ; returning from yield then continues with the next coroutine:
+        sys.pushw(task_return_address)
         return userdatas[active_task]
 
         sub next_task() -> bool {
             ; search through the task list for the next active task
             repeat len(tasklist) {
                 active_task++
-                if active_task==len(returnaddresses)
+                if active_task==len(tasklist)
                     active_task=0
-                task_start = tasklist[active_task]
-                if task_start!=0 {
-                    task_continue = returnaddresses[active_task]
+                task_return_address = tasklist[active_task]
+                if task_return_address!=0 {
                     return true
                 }
             }
@@ -128,9 +125,8 @@ resume_with_next_task:
         }
     }
 
-    sub kill(ubyte taskid) {
+    sub kill(ubyte @nozp taskid) {
         tasklist[taskid] = 0
-        returnaddresses[taskid] = 0
     }
 
     sub current() -> ubyte {
@@ -138,12 +134,10 @@ resume_with_next_task:
     }
 
     sub termination() {
-        ; a task has terminated. wipe it from the list.
-        ; this is an internal routine
+        ; internal routine: a task has terminated. wipe it from the list.
         kill(active_task)
-        ; reactivate this termination handler
-        ; note: cannot use pushw() because JSR doesn't push the return address in the same way
+        ; reactivate this termination handler and go to the next task
         sys.push_returnaddress(&termination)
-        goto coroutines.yield.resume_with_next_task
+        goto coroutines.yield.skip_task
     }
 }

compiler/res/prog8lib/cx16/bmx.p8

@@ -19,9 +19,9 @@ bmx {
     uword palette_entries       ; 1-256
     ubyte palette_start
     ubyte compression
-    uword @shared palette_buffer_ptr = 0    ; should you want to load or save the palette into main memory instead of directly into vram
+    ^^ubyte @shared palette_buffer_ptr = 0    ; should you want to load or save the palette into main memory instead of directly into vram
 
-    uword error_message             ; pointer to error message, or 0 if all ok
+    ^^ubyte error_message             ; pointer to error message, or 0 if all ok
     ubyte old_drivenumber
 
     sub open(ubyte drivenumber, str filename) -> bool {

compiler/res/prog8lib/cx16/diskio.p8

@@ -121,7 +121,7 @@ io_error:
         goto diskio.directory.internal_dir
     }
 
-    sub diskname() -> uword {
+    sub diskname() -> str {
         ; -- Returns pointer to disk name string or 0 if failure.
 
         cbm.SETNAM(1, "$")
@@ -165,7 +165,7 @@ io_error:
 
     ; internal variables for the iterative file lister / loader
     bool list_skip_disk_name
-    uword list_pattern
+    ^^ubyte list_pattern
     uword list_blocks
     bool iteration_in_progress = false
     bool write_iteration_in_progress = false
@@ -174,7 +174,7 @@ io_error:
 
     ; ----- get a list of files (uses iteration functions internally) -----
 
-    sub list_filenames(uword pattern_ptr, uword filenames_buffer, uword filenames_buf_size) -> ubyte {
+    sub list_filenames(str pattern_ptr, uword filenames_buffer, uword filenames_buf_size) -> ubyte {
         ; -- fill the provided buffer with the names of the files on the disk (until buffer is full).
         ;    Files in the buffer are separated by a 0 byte. You can provide an optional pattern to match against.
         ;    After the last filename one additional 0 byte is placed to indicate the end of the list.
@@ -209,7 +209,7 @@ io_error:
 
     ; ----- iterative file lister functions (uses the read io channel) -----
 
-    sub lf_start_list(uword pattern_ptr) -> bool {
+    sub lf_start_list(str pattern_ptr) -> bool {
         ; -- start an iterative file listing with optional pattern matching.
         ;    note: only a single iteration loop can be active at a time!
         cbm.SETNAM(1, "$")
@@ -239,7 +239,7 @@ io_error:
         return false
     }
 
-    sub lf_start_list_dirs(uword pattern_ptr) -> bool {
+    sub lf_start_list_dirs(str pattern_ptr) -> bool {
         ; -- start an iterative directory contents listing with optional pattern matching.
         ;    this version it only returns directory entries!
         ;    note: only a single iteration loop can be active at a time!
@@ -247,7 +247,7 @@ io_error:
         goto diskio.lf_start_list.start_list_internal
     }
 
-    sub lf_start_list_files(uword pattern_ptr) -> bool {
+    sub lf_start_list_files(str pattern_ptr) -> bool {
         ; -- start an iterative directory contents listing with optional pattern matching.
         ;    this version only returns actual file entries!
         ;    note: only a single iteration loop can be active at a time!
@@ -267,7 +267,7 @@ io_error:
         repeat {
             reset_read_channel()        ; use the input io channel again
 
-            uword nameptr = &list_filename
+            ^^ubyte nameptr = &list_filename
             ubyte blocks_lsb = cbm.CHRIN()
             ubyte blocks_msb = cbm.CHRIN()
 
@@ -460,7 +460,7 @@ byte_read_loop:         ; fallback if MACPTR isn't supported on the device
         return total_read
     }
 
-    asmsub f_readline(uword bufptr @AY) clobbers(X) -> ubyte @Y, ubyte @A {
+    asmsub f_readline(^^ubyte bufptr @AY) clobbers(X) -> ubyte @Y, ubyte @A {
         ; Routine to read text lines from a text file. Lines must be less than 255 characters.
         ; Reads characters from the input file UNTIL a newline or return character, or 0 byte (likely EOF).
         ; The line read will be 0-terminated in the buffer (and not contain the end of line character).
@@ -590,7 +590,7 @@ return_status:
 
     ; ---- other functions ----
 
-    sub status() -> uword {
+    sub status() -> str {
         ; -- retrieve the disk drive's current status message
 
 ; TODO this doesn't seem to work reliably, sometimes READST returns 128 when the drive is just fine
@@ -601,7 +601,7 @@ return_status:
 ;            return device_not_present_error
 ;        }
 
-        uword messageptr = &list_filename
+        ^^ubyte messageptr = &list_filename
         cbm.SETNAM(0, list_filename)
         cbm.SETLFS(15, drivenumber, 15)
         void cbm.OPEN()          ; open 15,8,15
@@ -663,16 +663,16 @@ io_error:
 
 
     ; saves a block of memory to disk, including the default 2 byte prg header.
-    sub save(uword filenameptr, uword startaddress, uword savesize) -> bool {
+    sub save(str filenameptr, uword startaddress, uword savesize) -> bool {
         return internal_save_routine(filenameptr, startaddress, savesize, false)
     }
 
     ; like save() but omits the 2 byte prg header.
-    sub save_raw(uword filenameptr, uword startaddress, uword savesize) -> bool {
+    sub save_raw(str filenameptr, uword startaddress, uword savesize) -> bool {
         return internal_save_routine(filenameptr, startaddress, savesize, true)
     }
 
-    sub internal_save_routine(uword filenameptr, uword startaddress, uword savesize, bool headerless) -> bool {
+    sub internal_save_routine(str filenameptr, uword startaddress, uword savesize, bool headerless) -> bool {
         cbm.SETNAM(strings.length(filenameptr), filenameptr)
         cbm.SETLFS(1, drivenumber, 0)
         uword @shared end_address = startaddress + savesize
@@ -719,25 +719,25 @@ io_error:
     ;       the return address will still be one higher. Which means, because the Kernal
     ;       load routine is bank-aware, it will return $a000 and will have switched to the next hiram bank!
     ;       So you'll have to reset the ram bank with cx16.rambank() to switch back to the bank that the data was put in.
-    sub load(uword filenameptr, uword address_override) -> uword {
+    sub load(str filenameptr, uword address_override) -> uword {
         return internal_load_routine(filenameptr, address_override, false)
     }
 
     ; Identical to load(), but DOES INCLUDE the first 2 bytes in the file.
     ; No program header is assumed in the file. Everything is loaded.
     ; See comments on load() for more details. Including the banking behavior on the X16.
-    sub load_raw(uword filenameptr, uword startaddress) -> uword {
+    sub load_raw(str filenameptr, uword startaddress) -> uword {
         return internal_load_routine(filenameptr, startaddress, true)
     }
 
 
     ; Load a prog8 compiled library binary blob at the given location into memory.
-    sub loadlib(uword libnameptr, uword libaddress) -> uword {
+    sub loadlib(str libnameptr, uword libaddress) -> uword {
         return internal_load_routine(libnameptr, libaddress, true)
     }
 
 
-    sub internal_load_routine(uword filenameptr, uword address_override, bool headerless) -> uword {
+    sub internal_load_routine(str filenameptr, uword address_override, bool headerless) -> uword {
         cbm.SETNAM(strings.length(filenameptr), filenameptr)
         ubyte secondary = 1
         cx16.r1 = 0
@@ -760,7 +760,7 @@ io_error:
         return cx16.r1
     }
 
-    sub delete(uword filenameptr) {
+    sub delete(str filenameptr) {
         ; -- delete a file on the drive
         list_filename[0] = 's'
         list_filename[1] = ':'
@@ -772,7 +772,7 @@ io_error:
         cbm.CLOSE(1)
     }
 
-    sub rename(uword oldfileptr, uword newfileptr) {
+    sub rename(str oldfileptr, str newfileptr) {
         ; -- rename a file on the drive
         list_filename[0] = 'r'
         list_filename[1] = ':'
@@ -786,7 +786,7 @@ io_error:
         cbm.CLOSE(1)
     }
 
-    sub send_command(uword commandptr) {
+    sub send_command(str commandptr) {
         ; -- send a dos command to the drive (don't read any response)
         cbm.SETNAM(strings.length(commandptr), commandptr)
         cbm.SETLFS(15, drivenumber, 15)
@@ -906,7 +906,7 @@ internal_vload:
         send_command(list_filename)
     }
 
-    sub curdir() -> uword {
+    sub curdir() -> str {
         ; return current directory name or 0 if error
         ; special X16 dos command to only return the current path in the entry list (R42+)
         const ubyte MAX_PATH_LEN=80

compiler/res/prog8lib/cx16/emudbg.p8

@@ -47,6 +47,12 @@ emudbg {
         }
     }
 
+    sub console_nl() {
+        ; write a newline to the debug output console.
+        ; because '\n' gets encoded in the x16 value for it (13) which is different than what the shell expects (10).
+        console_chrout(10)
+    }
+
     sub console_chrout(ubyte char) {
         ; note: make sure the character is in Iso encoding.
         if is_emulator()

compiler/res/prog8lib/cx16/floats.p8

@@ -21,8 +21,8 @@ extsub $fe00 = AYINT() clobbers(A,X,Y)          ; fac1-> signed word in 'facmo'
 ; (tip: use GIVAYFAY to use A/Y input; lo/hi switched to normal order)
 extsub $fe03 = GIVAYF(ubyte lo @ Y, ubyte hi @ A) clobbers(A,X,Y)
 
-extsub $fe06 = FOUT() clobbers(X) -> uword @ AY             ; fac1 -> string, address returned in AY
-extsub $fe09 = VAL_1(uword string @XY, ubyte length @A) clobbers(A,X,Y) -> float @FAC1      ; convert ASCII string in XY and length in A, to floating point in FAC1. WARNING: only implemented in ROM 47+. Safer to use floats.parse() instead.
+extsub $fe06 = FOUT() clobbers(X) -> str @ AY             ; fac1 -> string, address returned in AY
+extsub $fe09 = VAL_1(str string @XY, ubyte length @A) clobbers(A,X,Y) -> float @FAC1      ; convert ASCII string in XY and length in A, to floating point in FAC1. WARNING: only implemented in ROM 47+. Safer to use floats.parse() instead.
 
 ; GETADR: fac1 -> unsigned word in Y/A (might throw ILLEGAL QUANTITY) (result also in $14/15)
 ; (tip: use GETADRAY to get A/Y output; lo/hi switched to normal little endian order)

compiler/res/prog8lib/cx16/gfx_hires.p8

@@ -825,7 +825,7 @@ set_byte:
         cx16.screen_set_charset(charset, 0)
     }
 
-    sub text(uword @zp xx, uword yy, ubyte color, uword sctextptr) {
+    sub text(uword @zp xx, uword yy, ubyte color, str sctextptr) {
         ; -- Write some text at the given pixel position. The text string must be in screencode encoding (not petscii!).
         ;    You must also have called text_charset() first to select and prepare the character set to use.
         uword chardataptr

compiler/res/prog8lib/cx16/gfx_lores.p8

@@ -743,7 +743,7 @@ skip:
     const ubyte charset_bank = $1
     const uword charset_addr = $f000       ; in bank 1, so $1f000
 
-    sub text(uword @zp xx, uword yy, ubyte color, uword textptr) {
+    sub text(uword @zp xx, uword yy, ubyte color, str textptr) {
         ; -- Write some text at the given pixel position. The text string must be in an encoding approprite for the charset.
         ;    You must also have called text_charset() first to select and prepare the character set to use.
         uword chardataptr

compiler/res/prog8lib/cx16/monogfx.p8

@@ -22,18 +22,23 @@ monogfx {
     const ubyte MODE_STIPPLE = %00000001
     const ubyte MODE_INVERT  = %00000010
 
+    uword buffer_visible, buffer_back
+
+
     sub lores() {
         ; enable 320*240 bitmap mode
+        buffer_visible = buffer_back = $0000
         cx16.VERA_CTRL=0
         cx16.VERA_DC_VIDEO = (cx16.VERA_DC_VIDEO & %11001111) | %00100000      ; enable only layer 1
         cx16.VERA_DC_HSCALE = 64
         cx16.VERA_DC_VSCALE = 64
         cx16.VERA_L1_CONFIG = %00000100
         cx16.VERA_L1_MAPBASE = 0
-        cx16.VERA_L1_TILEBASE = 0
+        cx16.VERA_L1_TILEBASE = 0           ; lores
         width = 320
         height = 240
         lores_mode = true
+        buffer_visible = buffer_back = $0000
         mode = MODE_NORMAL
         clear_screen(false)
     }
@@ -46,14 +51,40 @@ monogfx {
         cx16.VERA_DC_VSCALE = 128
         cx16.VERA_L1_CONFIG = %00000100
         cx16.VERA_L1_MAPBASE = 0
-        cx16.VERA_L1_TILEBASE = %00000001
+        cx16.VERA_L1_TILEBASE = %00000001       ; hires
         width = 640
         height = 480
         lores_mode = false
+        buffer_visible = buffer_back = $0000
         mode = MODE_NORMAL
         clear_screen(false)
     }
 
+    sub enable_doublebuffer() {
+        ; enable double buffering mode
+        if lores_mode {
+            buffer_visible = $0000
+            buffer_back = $2800
+        } else {
+            buffer_visible = $0000
+            buffer_back = $9800
+        }
+    }
+
+    sub swap_buffers(bool wait_for_vsync) {
+        ; flip the buffers: make the back buffer visible and the other one now the backbuffer.
+        ; to avoid any screen tearing it is advised to call this during the vertical blank (pass true)
+        if wait_for_vsync
+            sys.waitvsync()
+        cx16.r0 = buffer_back
+        buffer_back = buffer_visible
+        buffer_visible = cx16.r0
+        cx16.VERA_CTRL = 0
+        cx16.r0 &= %1111110000000000
+        cx16.VERA_L1_TILEBASE = cx16.VERA_L1_TILEBASE & 1 | (cx16.r0H >>1 )
+    }
+
+
     sub textmode() {
         ; back to normal text mode
         cx16.r15L = cx16.VERA_DC_VIDEO & %00000111 ; retain chroma + output mode
@@ -559,6 +590,7 @@ drawmode:               ora  cx16.r15L
     sub disc(uword @zp xcenter, uword @zp ycenter, ubyte @zp radius, bool draw) {
         ; Warning: NO BOUNDS CHECKS. Make sure circle fits in the screen.
         ; Midpoint algorithm, filled
+        ; Note: has problems with INVERT draw mode because of horizontal span overdrawing. Horizontal lines may occur.
         if radius==0
             return
         ubyte @zp yy = 0
@@ -597,6 +629,7 @@ drawmode:               ora  cx16.r15L
     sub safe_disc(uword @zp xcenter, uword @zp ycenter, ubyte @zp radius, bool draw) {
         ; Does bounds checking and clipping.
         ; Midpoint algorithm, filled
+        ; Note: has problems with INVERT draw mode because of horizontal span overdrawing. Horizontal lines may occur.
         if radius==0
             return
         ubyte @zp yy = 0
@@ -672,8 +705,7 @@ nostipple:
 invert:
         prepare()
         %asm {{
-            lda  cx16.VERA_DATA0
-            eor  p8v_maskbits,y
+            eor  cx16.VERA_DATA0
             sta  cx16.VERA_DATA0
         }}
         return
@@ -696,7 +728,7 @@ invert:
                     adc  p8v_times40_lsb,y
                     sta  cx16.VERA_ADDR_L
                     lda  p8v_times40_msb,y
-                    adc  #0
+                    adc  p8v_buffer_back+1
                     sta  cx16.VERA_ADDR_M
 
                     lda  p8v_xx
@@ -708,18 +740,29 @@ invert:
                 ; width=640 (hires)
                 %asm {{
                     stz  cx16.VERA_CTRL
-                    stz  cx16.VERA_ADDR_H
                     lda  p8v_xx
                     and  #7
                     pha     ; xbits
+
+                    ; xx /= 8
+                    lsr  p8v_xx+1
+                    ror  p8v_xx
+                    lsr  p8v_xx+1
+                    ror  p8v_xx
+                    lsr  p8v_xx
                 }}
-                xx /= 8
+                ;xx /= 8
                 xx += yy*(640/8)
                 %asm {{
-                    lda  p8v_xx+1
-                    sta  cx16.VERA_ADDR_M
                     lda  p8v_xx
                     sta  cx16.VERA_ADDR_L
+                    lda  p8v_xx+1
+                    clc
+                    adc  p8v_buffer_back+1
+                    sta  cx16.VERA_ADDR_M
+                    lda  #0
+                    rol  a   ; hi bit carry also needed when double-buffering
+                    sta  cx16.VERA_ADDR_H
                     plx     ; xbits
                     lda  p8v_maskbits,x
                 }}
@@ -761,11 +804,15 @@ invert:
 
         %asm {{
             stz  cx16.VERA_CTRL
-            stz  cx16.VERA_ADDR_H
-            lda  p8v_xx+1
-            sta  cx16.VERA_ADDR_M
             lda  p8v_xx
             sta  cx16.VERA_ADDR_L
+            lda  p8v_xx+1
+            clc
+            adc  p8v_buffer_back+1
+            sta  cx16.VERA_ADDR_M
+            lda  #0
+            rol  a   ; hi bit carry also needed when double-buffering
+            sta  cx16.VERA_ADDR_H
             ply         ; xbits
             lda  p8s_plot.p8v_maskbits,y
             and  cx16.VERA_DATA0
@@ -848,8 +895,8 @@ skip:
         }
 
         sub fill_scanline_right() {
-             ; TODO maybe this could use vera auto increment, but that requires some clever masking calculations
-             cx16.r9s = xx
+            ; TODO maybe this could use vera auto increment, but that requires some clever masking calculations
+            cx16.r9s = xx
             while xx <= width-1 {
                 if pgetset()
                     break
@@ -884,11 +931,15 @@ skip:
 
             %asm {{
                 stz  cx16.VERA_CTRL
-                stz  cx16.VERA_ADDR_H
-                lda  p8v_xpos+1
-                sta  cx16.VERA_ADDR_M
                 lda  p8v_xpos
                 sta  cx16.VERA_ADDR_L
+                lda  p8v_xpos+1
+                clc
+                adc  p8v_buffer_back+1
+                sta  cx16.VERA_ADDR_M
+                lda  #0
+                rol  a   ; hi bit carry also needed when double-buffering
+                sta  cx16.VERA_ADDR_H
                 ply         ; xbits
                 lda  p8s_plot.p8v_maskbits,y
                 and  cx16.VERA_DATA0
@@ -935,12 +986,12 @@ _doplot         beq  +
                 ror  a
                 lsr  a
                 lsr  a
-                clc
                 ldy  p8v_yy
+                clc
                 adc  p8v_times40_lsb,y
                 sta  cx16.VERA_ADDR_L
                 lda  p8v_times40_msb,y
-                adc  #0
+                adc  p8v_buffer_back+1
                 sta  cx16.VERA_ADDR_M
                 lda  #%00010000     ; autoincr
                 sta  cx16.VERA_ADDR_H
@@ -948,7 +999,33 @@ _doplot         beq  +
         }
         else {
             cx16.r0 = yy*(640/8)
-            cx16.vaddr(0, cx16.r0+(xx/8), 0, 1)
+            ;cx16.r0 += xx/8
+            %asm {{
+            	ldy  p8v_xx+1
+                lda  p8v_xx
+                sty  P8ZP_SCRATCH_B1
+                lsr  P8ZP_SCRATCH_B1
+                ror  a
+                lsr  P8ZP_SCRATCH_B1
+                ror  a
+                lsr  a
+                clc
+                adc  cx16.r0
+                sta  cx16.r0
+                bcc  +
+                inc  cx16.r0+1
++
+                stz  cx16.VERA_CTRL
+                lda  cx16.r0L
+                sta  cx16.VERA_ADDR_L
+                lda  cx16.r0H
+                clc
+                adc  p8v_buffer_back+1
+                sta  cx16.VERA_ADDR_M
+                lda  #%00001000     ; autoincr (1 bit shifted)
+                rol  a              ; hi bit carry also needed when double-buffering
+                sta  cx16.VERA_ADDR_H
+            }}
         }
         return
     }
@@ -1116,15 +1193,11 @@ cdraw_mod2              ora  cx16.VERA_DATA1
             cmp  #0
             beq  +
             lda  #255
-+           ldy  #80
--           sta  cx16.VERA_DATA0
-            sta  cx16.VERA_DATA0
-            sta  cx16.VERA_DATA0
-            sta  cx16.VERA_DATA0
-            sta  cx16.VERA_DATA0
-            sta  cx16.VERA_DATA0
-            sta  cx16.VERA_DATA0
++           ldy  #40
+-
+            .rept  16
             sta  cx16.VERA_DATA0
+            .endrept
             dey
             bne  -
             rts

compiler/res/prog8lib/cx16/sprites.p8

@@ -89,18 +89,18 @@ sprites {
         sprite_reg = VERA_SPRITEREGS + 2 + first_spritenum*$0008
         cx16.vaddr_autoincr(1, sprite_reg, 0, 8)
         cx16.vaddr_autoincr(1, sprite_reg+1, 1, 8)
-        repeat num_sprites {
-            cx16.VERA_DATA0 = @(xpositions_ptr)
-            cx16.VERA_DATA1 = @(xpositions_ptr+num_sprites)
-            xpositions_ptr ++
-        }
+        tovera(xpositions_ptr)
         sprite_reg += 2
         cx16.vaddr_autoincr(1, sprite_reg, 0, 8)
         cx16.vaddr_autoincr(1, sprite_reg+1, 1, 8)
-        repeat num_sprites {
-            cx16.VERA_DATA0 = @(ypositions_ptr)
-            cx16.VERA_DATA1 = @(ypositions_ptr+num_sprites)
-            ypositions_ptr ++
+        tovera(ypositions_ptr)
+
+        sub tovera(uword positions @R0) {
+            repeat num_sprites {
+                cx16.VERA_DATA0 = @(cx16.r0)
+                cx16.VERA_DATA1 = @(cx16.r0+num_sprites)
+                cx16.r0 ++
+            }
         }
     }
 
@@ -109,20 +109,19 @@ sprites {
         sprite_reg = VERA_SPRITEREGS + 2 + first_spritenum*$0008
         cx16.vaddr_autoincr(1, sprite_reg, 0, 8)
         cx16.vaddr_autoincr(1, sprite_reg+1, 1, 8)
-        repeat num_sprites {
-            cx16.VERA_DATA0 = @(xpositions_ptr)
-            xpositions_ptr ++
-            cx16.VERA_DATA1 = @(xpositions_ptr)
-            xpositions_ptr ++
-        }
+        tovera(xpositions_ptr)
         sprite_reg += 2
         cx16.vaddr_autoincr(1, sprite_reg, 0, 8)
         cx16.vaddr_autoincr(1, sprite_reg+1, 1, 8)
-        repeat num_sprites {
-            cx16.VERA_DATA0 = @(ypositions_ptr)
-            ypositions_ptr ++
-            cx16.VERA_DATA1 = @(ypositions_ptr)
-            ypositions_ptr ++
+        tovera(ypositions_ptr)
+
+        sub tovera(uword positions @R0) {
+            repeat num_sprites {
+                cx16.VERA_DATA0 = @(cx16.r0)
+                cx16.r0 ++
+                cx16.VERA_DATA1 = @(cx16.r0)
+                cx16.r0 ++
+            }
         }
     }
 

compiler/res/prog8lib/cx16/syslib.p8

@@ -177,6 +177,7 @@ cx16 {
     &uword r14 = $001e
     &uword r15 = $0020
 
+    ; signed word versions
     &word r0s  = $0002
     &word r1s  = $0004
     &word r2s  = $0006
@@ -194,6 +195,7 @@ cx16 {
     &word r14s = $001e
     &word r15s = $0020
 
+    ; ubyte versions (low and high bytes)
     &ubyte r0L  = $0002
     &ubyte r1L  = $0004
     &ubyte r2L  = $0006
@@ -228,6 +230,7 @@ cx16 {
     &ubyte r14H = $001f
     &ubyte r15H = $0021
 
+    ; signed byte versions (low and high bytes)
     &byte r0sL  = $0002
     &byte r1sL  = $0004
     &byte r2sL  = $0006
@@ -262,6 +265,42 @@ cx16 {
     &byte r14sH = $001f
     &byte r15sH = $0021
 
+    ; boolean versions
+    &bool r0bL  = $0002
+    &bool r1bL  = $0004
+    &bool r2bL  = $0006
+    &bool r3bL  = $0008
+    &bool r4bL  = $000a
+    &bool r5bL  = $000c
+    &bool r6bL  = $000e
+    &bool r7bL  = $0010
+    &bool r8bL  = $0012
+    &bool r9bL  = $0014
+    &bool r10bL = $0016
+    &bool r11bL = $0018
+    &bool r12bL = $001a
+    &bool r13bL = $001c
+    &bool r14bL = $001e
+    &bool r15bL = $0020
+
+    &bool r0bH  = $0003
+    &bool r1bH  = $0005
+    &bool r2bH  = $0007
+    &bool r3bH  = $0009
+    &bool r4bH  = $000b
+    &bool r5bH  = $000d
+    &bool r6bH  = $000f
+    &bool r7bH  = $0011
+    &bool r8bH  = $0013
+    &bool r9bH  = $0015
+    &bool r10bH = $0017
+    &bool r11bH = $0019
+    &bool r12bH = $001b
+    &bool r13bH = $001d
+    &bool r14bH = $001f
+    &bool r15bH = $0021
+
+
 ; VERA registers
 
     const uword VERA_BASE       = $9F20
@@ -474,7 +513,7 @@ extsub $ff68 = mouse_config(byte shape @A, ubyte resX @X, ubyte resY @Y)  clobbe
 extsub $ff6b = mouse_get(ubyte zdataptr @X) -> ubyte @A, byte @X    ;  use mouse_pos() instead
 extsub $ff71 = mouse_scan()  clobbers(A, X, Y)
 extsub $ff53 = joystick_scan()  clobbers(A, X, Y)
-extsub $ff56 = joystick_get(ubyte joynr @A) -> uword @AX, bool @Y   ; note: everything is inverted
+extsub $ff56 = joystick_get(ubyte joynr @A) -> uword @AX, bool @Y   ; note: everything is inverted even the boolean present flag.  Also see detect_joysticks() and get_all_joysticks()
 
 ; X16Edit (rom bank 13/14 but you ideally should use the routine search_x16edit() to search for the correct bank)
 extsub $C000 = x16edit_default() clobbers(A,X,Y)
@@ -1168,8 +1207,39 @@ asmsub restore_vera_context() clobbers(A) {
         }}
     }
 
+    sub joysticks_detect() -> ubyte {
+        ; returns bits 0-4,  set to 1 if that joystick is present.
+        ; bit 0 = keyboard joystick, bit 1 - 4 = joypads 1 to 4
+        cx16.r0H = 255
+        for cx16.r0L in 4 downto 0 {
+            void cx16.joystick_get(cx16.r0L)
+            %asm {{
+                cpy  #1     ; present?
+            }}
+            rol(cx16.r0H)
+        }
+        return ~cx16.r0H
+    }
 
-    ; Commander X16 IRQ dispatcher routines
+    sub joysticks_getall(bool also_keyboard_js) -> uword {
+        ; returns combined pressed buttons from all connected joysticks
+        ; note: returns the 'normal' not inverted status bits for the buttons (1 = button pressed.)
+        cx16.r0H = 1
+        if also_keyboard_js
+            cx16.r0H = 0
+        cx16.r1 = $ffff
+        for cx16.r0L in cx16.r0H to 4 {
+            bool notpresent
+            cx16.r2, notpresent = cx16.joystick_get(cx16.r0L)
+            if not notpresent {
+                cx16.r1 &= cx16.r2
+            }
+        }
+        return ~cx16.r1
+    }
+
+
+; Commander X16 IRQ dispatcher routines
 
 inline asmsub  disable_irqs() clobbers(A) {
     ; Disable all Vera IRQ sources. Note that it does NOT set the CPU IRQ disabled status bit!
@@ -1216,6 +1286,7 @@ _vsync_vec   .word  ?
 _line_vec    .word  ?
 _aflow_vec   .word  ?
 _sprcol_vec  .word  ?
+_continue_with_system_handler   .byte  ?
         .send BSS
 
 _irq_dispatcher
@@ -1224,44 +1295,42 @@ _irq_dispatcher
         cld
         lda  cx16.VERA_ISR
         and  cx16.VERA_IEN          ; only consider the bits for sources that can actually raise the IRQ
+        sta  cx16.VERA_ISR          ; note: AFLOW can only be cleared by filling the audio FIFO for at least 1/4. Not via the ISR bit.
 
-        bit  #2
+        stz  _continue_with_system_handler
+
+        bit  #2         ; make sure to test for LINE IRQ first to handle that as soon as we can
         beq  +
+        pha
         jsr  _line_handler
-        ldy  #2
-        sty  cx16.VERA_ISR
-        bra  _dispatch_end
-+
-        bit  #4
-        beq  +
-        jsr  _sprcol_handler
-        ldy  #4
-        sty  cx16.VERA_ISR
-        bra  _dispatch_end
-+
-        bit  #8
-        beq  +
-        jsr  _aflow_handler
-        ; note: AFLOW can only be cleared by filling the audio FIFO for at least 1/4. Not via the ISR bit.
-        bra  _dispatch_end
-+
-        bit  #1
-        beq  +
+        tsb  _continue_with_system_handler
+        pla
+
++       lsr  a
+        bcc  +
+        pha
         jsr  _vsync_handler
-        cmp  #0
-        bne  _dispatch_end
-        ldy  #1
-        sty  cx16.VERA_ISR
-        bra  _return_irq
-+
-        lda  #0
-_dispatch_end
-        cmp  #0
-        beq  _return_irq
-        jsr  sys.restore_prog8_internals
+        tsb  _continue_with_system_handler
+        pla
+
++       lsr  a
+        lsr  a
+        bcc  +
+        pha
+        jsr  _sprcol_handler
+        tsb  _continue_with_system_handler
+        pla
+
++       lsr  a
+        bcc  +
+        jsr  _aflow_handler
+        tsb  _continue_with_system_handler
+
++       jsr  sys.restore_prog8_internals
+        lda  _continue_with_system_handler
+        beq  _no_sys_handler
 		jmp  (sys.restore_irq._orig_irqvec)   ; continue with normal kernal irq routine
-_return_irq
-        jsr  sys.restore_prog8_internals
+_no_sys_handler
 		ply
 		plx
 		pla
@@ -1401,7 +1470,7 @@ sub search_x16edit() -> ubyte {
         }}
     }
 
-    sub set_program_args(uword args_ptr, ubyte args_size) {
+    sub set_program_args(str args_ptr, ubyte args_size) {
         ; -- Set the inter-program arguments.
         ; standardized way to pass arguments between programs is in ram bank 0, address $bf00-$bfff.
         ; see https://github.com/X16Community/x16-docs/blob/101759f3bfa5e6cce4e8c5a0b67cb0f2f1c6341e/X16%20Reference%20-%2008%20-%20Memory%20Map.md#bank-0
@@ -1413,7 +1482,7 @@ sub search_x16edit() -> ubyte {
         rambank(sys.pop())
     }
 
-    asmsub get_program_args(uword buffer @R0, ubyte buf_size @R1, bool binary @Pc) {
+    asmsub get_program_args(^^ubyte buffer @R0, ubyte buf_size @R1, bool binary @Pc) {
         ; -- Retrieve the inter-program arguments. If binary=false, it treats them as a string (stops copying at first zero).
         ; standardized way to pass arguments between programs is in ram bank 0, address $bf00-$bfff.
         ; see https://github.com/X16Community/x16-docs/blob/101759f3bfa5e6cce4e8c5a0b67cb0f2f1c6341e/X16%20Reference%20-%2008%20-%20Memory%20Map.md#bank-0
@@ -1485,12 +1554,14 @@ sys {
 
     const ubyte target = 16         ;  compilation target specifier.  255=virtual, 128=C128, 64=C64, 32=PET, 16=CommanderX16, 8=atari800XL, 7=Neo6502
 
-    const ubyte SIZEOF_BOOL  = 1
-    const ubyte SIZEOF_BYTE  = 1
-    const ubyte SIZEOF_UBYTE = 1
-    const ubyte SIZEOF_WORD  = 2
-    const ubyte SIZEOF_UWORD = 2
-    const ubyte SIZEOF_FLOAT = 5
+    const ubyte SIZEOF_BOOL  = sizeof(bool)
+    const ubyte SIZEOF_BYTE  = sizeof(byte)
+    const ubyte SIZEOF_UBYTE = sizeof(ubyte)
+    const ubyte SIZEOF_WORD  = sizeof(word)
+    const ubyte SIZEOF_UWORD = sizeof(uword)
+    const ubyte SIZEOF_LONG  = sizeof(long)
+    const ubyte SIZEOF_POINTER = sizeof(&sys.wait)
+    const ubyte SIZEOF_FLOAT = sizeof(float)
     const byte  MIN_BYTE     = -128
     const byte  MAX_BYTE     = 127
     const ubyte MIN_UBYTE    = 0
@@ -1688,7 +1759,7 @@ _loop       lda  P8ZP_SCRATCH_W1
         }}
     }
 
-    asmsub internal_stringcopy(uword source @R0, uword target @AY) clobbers (A,Y) {
+    asmsub internal_stringcopy(str source @R0, str target @AY) clobbers (A,Y) {
         ; Called when the compiler wants to assign a string value to another string.
         %asm {{
 		sta  P8ZP_SCRATCH_W1
@@ -1997,6 +2068,18 @@ save_SCRATCH_ZPWORD2	.word  ?
         }}
     }
 
+    asmsub get_as_returnaddress(uword address @XY) -> uword @AX {
+        %asm {{
+            ; return the address like JSR would push onto the stack:  address-1,  MSB first then LSB
+            cpx  #0
+            bne  +
+            dey
++           dex
+            tya
+            rts
+        }}
+    }
+
     inline asmsub pop() -> ubyte @A {
         %asm {{
             pla

compiler/res/prog8lib/cx16/textio.p8

@@ -17,26 +17,6 @@ const long VERA_TEXTMATRIX = $1b000
 extsub $FFD2 = chrout(ubyte character @ A)    ; for consistency. You can also use cbm.CHROUT directly ofcourse. Note: takes a PETSCII encoded character.
 
 
-sub clear_screen() {
-    chrout(147)
-}
-
-sub cls() {
-    chrout(147)
-}
-
-sub home() {
-    chrout(19)
-}
-
-sub nl() {
-    chrout('\n')
-}
-
-sub spc() {
-    chrout(' ')
-}
-
 sub bell() {
     chrout(7)
 }

compiler/res/prog8lib/cx16/verafx.p8

@@ -119,6 +119,7 @@ verafx {
         ; Returns the 16 bits unsigned result of R0*R1 in AY.
         ; Note: only the lower 16 bits!   (the upper 16 bits are not valid for unsigned word multiplications, only for signed)
         ; Verafx doesn't support unsigned values like this for full 32 bit result.
+        ; Note: clobbers VRAM $1f9bc - $1f9bf (inclusive)
         %asm {{
             lda  cx16.r0
             sta  P8ZP_SCRATCH_W1
@@ -136,6 +137,7 @@ verafx {
     asmsub muls(word value1 @R0, word value2 @R1) clobbers(X) -> word @AY, word @R0 {
         ; Returns the 32 bits signed result in AY and R0  (lower word, upper word).
         ; Vera Fx multiplication support only works on signed values!
+        ; Note: clobbers VRAM $1f9bc - $1f9bf (inclusive)
         %asm {{
             lda  #(2 << 1)
             sta  cx16.VERA_CTRL        ; $9F25

compiler/res/prog8lib/cx16logo.p8

@@ -6,7 +6,7 @@ cx16logo {
     %option ignore_unused
 
     sub logo_at(ubyte column, ubyte row) {
-        uword strptr
+        ^^ubyte strptr
         for strptr in logo_lines {
             txt.plot(column, row)
             txt.print(strptr)
@@ -15,7 +15,7 @@ cx16logo {
     }
 
     sub logo() {
-        uword strptr
+        ^^ubyte strptr
         for strptr in logo_lines {
             txt.print(strptr)
             txt.nl()

compiler/res/prog8lib/math.asm

@@ -3,7 +3,7 @@
 ;
 ;  some more interesting routines can be found here:
 ;	http://6502org.wikidot.com/software-math
-;	http://codebase64.org/doku.php?id=base:6502_6510_maths
+;	https://codebase64.net/doku.php?id=base:6502_6510_maths
 ;       https://github.com/TobyLobster/multiply_test
 ;       https://github.com/TobyLobster/sqrt_test
 
@@ -241,6 +241,28 @@ divmod_ub_asm	.proc
 		rts
 		.pend
 
+remainder_ub_asm        .proc
+		; -- divide A by Y, returns remainder in A   (unsigned)
+		;    division by zero will result in just the original number.
+		;    This routine specialcases 0,1,2 and otherwise is just a repeated subtraction.
+		cpy  #0
+		beq  _zero
+		cpy  #1
+		bne  +
+		lda  #0
+		rts
++		cpy  #2
+		bne  +
+		and  #1
+		rts
++		sty  P8ZP_SCRATCH_REG
+		sec
+-		sbc  P8ZP_SCRATCH_REG
+		bcs  -
+		adc  P8ZP_SCRATCH_REG
+_zero		rts
+		.pend
+
 divmod_w_asm	.proc
 	; signed word division: make everything positive and fix sign afterwards
 		sta  P8ZP_SCRATCH_W2
@@ -331,7 +353,7 @@ _divisor	.word ?
 randword	.proc
 	; -- 16 bit pseudo random number generator into AY
 	;    default seed = $00c2 $1137.  NOTE:  uses self-modifying code so won't work in ROM (use randword_rom instead)
-        ;    routine from https://codebase64.org/doku.php?id=base:x_abc_random_number_generator_8_16_bit
+        ;    routine from https://codebase64.net/doku.php?id=6502_6510_maths:x_abc_random_number_generator_8_16_bit
 		inc x1
 		clc
 x1=*+1
@@ -355,7 +377,7 @@ b1=*+1
 randword_rom	.proc
 	; -- 16 bit pseudo random number generator into AY. Can run from ROM.
 	;    NOTE: you have to set the initial seed using randseed_rom! (a good default seed = $00c2 $1137)
-        ;    routine from https://codebase64.org/doku.php?id=base:x_abc_random_number_generator_8_16_bit
+        ;    routine from https://codebase64.net/doku.php?id=6502_6510_maths:x_abc_random_number_generator_8_16_bit
 		inc  _x1
 		clc
 		lda  _x1

compiler/res/prog8lib/math.p8

@@ -102,43 +102,35 @@ _sinecosR8	.char  trunc(127.0 * sin(range(180+45) * rad(360.0/180.0)))
     }
 
     sub randrange(ubyte n) -> ubyte {
-        ; -- return random number uniformly distributed from 0 to n-1 (compensates for divisibility bias).
-        ;    NOTE: does not work for code in ROM
-        cx16.r0H = 255 / n * n
-        do {
-            cx16.r0L = math.rnd()
-        } until cx16.r0L < cx16.r0H
-        return cx16.r0L % n
+        ; -- return random number uniformly distributed from 0 to n-1
+        ;    NOTE: does not work for code in ROM, use randrange_rom instead for that
+        ; why this works: https://www.youtube.com/watch?v=3DvlLUWTNMY&t=347s
+        cx16.r0 = math.rnd() * (n as uword)
+        return cx16.r0H
     }
 
     sub randrange_rom(ubyte n) -> ubyte {
-        ; -- return random number uniformly distributed from 0 to n-1 (compensates for divisibility bias).
-        ;    NOTE: works for code in ROM, make sure to initialize seed using rndseed_rom
-        cx16.r0H = 255 / n * n
-        do {
-            cx16.r0L = math.rnd_rom()
-        } until cx16.r0L < cx16.r0H
-        return cx16.r0L % n
+        ; -- return random number uniformly distributed from 0 to n-1
+        ;    NOTE: works for code in ROM, make sure you have initialized the seed using rndseed_rom
+        ; why this works: https://www.youtube.com/watch?v=3DvlLUWTNMY&t=347s
+        cx16.r0 = math.rnd_rom() * (n as uword)
+        return cx16.r0H
     }
 
     sub randrangew(uword n) -> uword {
-        ; -- return random number uniformly distributed from 0 to n-1 (compensates for divisibility bias)
+        ; -- return random number uniformly distributed from 0 to n-1
         ;    NOTE: does not work for code in ROM
-        cx16.r1 = 65535 / n * n
-        do {
-            cx16.r0 = math.rndw()
-        } until cx16.r0 < cx16.r1
-        return cx16.r0 % n
+        ; why this works: https://www.youtube.com/watch?v=3DvlLUWTNMY&t=347s
+        cx16.r0 = math.rndw() * n
+        return math.mul16_last_upper()
     }
 
     sub randrangew_rom(uword n) -> uword {
-        ; -- return random number uniformly distributed from 0 to n-1 (compensates for divisibility bias)
-        ;    NOTE: works for code in ROM, make sure to initialize seed using rndseed_rom
-        cx16.r1 = 65535 / n * n
-        do {
-            cx16.r0 = math.rndw_rom()
-        } until cx16.r0 < cx16.r1
-        return cx16.r0 % n
+        ; -- return random number uniformly distributed from 0 to n-1
+        ;    NOTE: works for code in ROM, make sure you have initialized the seed using rndseed_rom
+        ; why this works: https://www.youtube.com/watch?v=3DvlLUWTNMY&t=347s
+        cx16.r0 = math.rndw_rom() * n
+        return math.mul16_last_upper()
     }
 
     asmsub rndseed(uword seed1 @AY, uword seed2 @R0) clobbers(A,Y) {
@@ -388,7 +380,7 @@ _quadrant_region_to_direction:
 asmsub atan2(ubyte x1 @R0, ubyte y1 @R1, ubyte x2 @R2, ubyte y2 @R3) -> ubyte @A {
     ;; Calculate the angle, in a 256-degree circle, between two points into A.
     ;; The points (x1, y1) and (x2, y2) have to use *unsigned coordinates only* from the positive quadrant in the carthesian plane!
-    ;; https://www.codebase64.org/doku.php?id=base:8bit_atan2_8-bit_angle
+    ;; http://codebase64.net/doku.php?id=base:8bit_atan2_8-bit_angle
     ;; This uses 2 large lookup tables so uses a lot of memory but is super fast.
 
     %asm {{
@@ -555,7 +547,7 @@ log2_tab
         }}
     }
 
-    sub crc16(uword data, uword length) -> uword {
+    sub crc16(^^ubyte data, uword length) -> uword {
         ; calculates the CRC16 (XMODEM) checksum of the buffer.
         ; There are also "streaming" crc16_start/update/end routines below, that allow you to calculate crc16 for data that doesn't fit in a single memory block.
         crc16_start()
@@ -610,7 +602,7 @@ log2_tab
         return cx16.r15
     }
 
-    sub crc32(uword data, uword length) {
+    sub crc32(^^ubyte data, uword length) {
         ; Calculates the CRC-32 (ISO-HDLC/PKZIP) checksum of the buffer.
         ; because prog8 doesn't have 32 bits integers, we have to split up the calculation over 2 words.
         ; result stored in cx16.r14 (low word) and cx16.r15 (high word)
@@ -705,25 +697,36 @@ log2_tab
         ; Linear interpolation (LERP)
         ; returns an interpolation between two inputs (v0, v1) for a parameter t in the interval [0, 255]
         ; guarantees v = v1 when t = 255
-        return v0 + msb(t as uword * (v1 - v0) + 255)
+        if v1<v0
+            return v0 - msb(t as uword * (v0 - v1) + 255)
+        else
+            return v0 + msb(t as uword * (v1 - v0) + 255)
     }
 
     sub lerpw(uword v0, uword v1, uword t) -> uword {
         ; Linear interpolation (LERP) on word values
         ; returns an interpolation between two inputs (v0, v1) for a parameter t in the interval [0, 65535]
-        ; guarantees v = v1 when t = 65535
+        ; guarantees v = v1 when t = 65535.  Clobbers R15.
+        if v1<v0 {
+            t *= v0-v1
+            cx16.r15 = math.mul16_last_upper()
+            if t!=0
+                cx16.r15++
+            return v0 - cx16.r15
+        }
         t *= v1-v0
-        cx16.r0 = math.mul16_last_upper()
+        cx16.r15 = math.mul16_last_upper()
         if t!=0
-            cx16.r0++
-        return v0 + cx16.r0
+            cx16.r15++
+        return v0 + cx16.r15
     }
 
     sub interpolate(ubyte v, ubyte inputMin, ubyte inputMax, ubyte outputMin, ubyte outputMax) -> ubyte {
         ; Interpolate a value v in interval [inputMin, inputMax] to output interval [outputMin, outputMax]
-        ; There is no version for words because of lack of precision in the fixed point calculation there.
-        cx16.r0 = ((v-inputMin)*256+inputMax) / (inputMax-inputMin)
-        cx16.r0 *= (outputMax-outputMin)
-        return cx16.r0H + outputMin
+        ; Clobbers R15.
+        ; (There is no version for words because of lack of precision in the fixed point calculation there)
+        cx16.r15 = ((v-inputMin)*256+inputMax) / (inputMax-inputMin)
+        cx16.r15 *= (outputMax-outputMin)
+        return cx16.r15H + outputMin
     }
 }

compiler/res/prog8lib/pet32/syslib.p8

@@ -98,12 +98,14 @@ sys {
 
     const ubyte target = 32         ;  compilation target specifier.  255=virtual, 128=C128, 64=C64, 32=PET, 16=CommanderX16, 8=atari800XL, 7=Neo6502
 
-    const ubyte SIZEOF_BOOL  = 1
-    const ubyte SIZEOF_BYTE  = 1
-    const ubyte SIZEOF_UBYTE = 1
-    const ubyte SIZEOF_WORD  = 2
-    const ubyte SIZEOF_UWORD = 2
-    const ubyte SIZEOF_FLOAT = 0    ; undefined, no floats supported
+    const ubyte SIZEOF_BOOL  = sizeof(bool)
+    const ubyte SIZEOF_BYTE  = sizeof(byte)
+    const ubyte SIZEOF_UBYTE = sizeof(ubyte)
+    const ubyte SIZEOF_WORD  = sizeof(word)
+    const ubyte SIZEOF_UWORD = sizeof(uword)
+    const ubyte SIZEOF_LONG  = sizeof(long)
+    const ubyte SIZEOF_POINTER = sizeof(&sys.wait)
+    const ubyte SIZEOF_FLOAT = sizeof(float)
     const byte  MIN_BYTE     = -128
     const byte  MAX_BYTE     = 127
     const ubyte MIN_UBYTE    = 0
@@ -161,7 +163,7 @@ _loop       lda  P8ZP_SCRATCH_W1
         }}
     }
 
-    asmsub internal_stringcopy(uword source @R0, uword target @AY) clobbers (A,Y) {
+    asmsub internal_stringcopy(str source @R0, str target @AY) clobbers (A,Y) {
         ; Called when the compiler wants to assign a string value to another string.
         %asm {{
 		sta  P8ZP_SCRATCH_W1
@@ -481,6 +483,18 @@ save_SCRATCH_ZPWORD2	.word  ?
         }}
     }
 
+    asmsub get_as_returnaddress(uword address @XY) -> uword @AX {
+        %asm {{
+            ; return the address like JSR would push onto the stack:  address-1,  MSB first then LSB
+            cpx  #0
+            bne  +
+            dey
++           dex
+            tya
+            rts
+        }}
+    }
+
     inline asmsub pop() -> ubyte @A {
         %asm {{
             pla
@@ -519,6 +533,7 @@ cx16 {
     &uword r14 = $7ffc
     &uword r15 = $7ffe
 
+    ; signed word versions
     &word r0s  = $7fe0
     &word r1s  = $7fe2
     &word r2s  = $7fe4
@@ -536,6 +551,7 @@ cx16 {
     &word r14s = $7ffc
     &word r15s = $7ffe
 
+    ; ubyte versions (low and high bytes)
     &ubyte r0L  = $7fe0
     &ubyte r1L  = $7fe2
     &ubyte r2L  = $7fe4
@@ -570,6 +586,7 @@ cx16 {
     &ubyte r14H = $7ffd
     &ubyte r15H = $7fff
 
+    ; signed byte versions (low and high bytes)
     &byte r0sL  = $7fe0
     &byte r1sL  = $7fe2
     &byte r2sL  = $7fe4
@@ -604,6 +621,42 @@ cx16 {
     &byte r14sH = $7ffd
     &byte r15sH = $7fff
 
+    ; boolean versions
+    &bool r0bL  = $7fe0
+    &bool r1bL  = $7fe2
+    &bool r2bL  = $7fe4
+    &bool r3bL  = $7fe6
+    &bool r4bL  = $7fe8
+    &bool r5bL  = $7fea
+    &bool r6bL  = $7fec
+    &bool r7bL  = $7fee
+    &bool r8bL  = $7ff0
+    &bool r9bL  = $7ff2
+    &bool r10bL = $7ff4
+    &bool r11bL = $7ff6
+    &bool r12bL = $7ff8
+    &bool r13bL = $7ffa
+    &bool r14bL = $7ffc
+    &bool r15bL = $7ffe
+
+    &bool r0bH  = $7fe1
+    &bool r1bH  = $7fe3
+    &bool r2bH  = $7fe5
+    &bool r3bH  = $7fe7
+    &bool r4bH  = $7fe9
+    &bool r5bH  = $7feb
+    &bool r6bH  = $7fed
+    &bool r7bH  = $7fef
+    &bool r8bH  = $7ff1
+    &bool r9bH  = $7ff3
+    &bool r10bH = $7ff5
+    &bool r11bH = $7ff7
+    &bool r12bH = $7ff9
+    &bool r13bH = $7ffb
+    &bool r14bH = $7ffd
+    &bool r15bH = $7fff
+
+
     asmsub save_virtual_registers() clobbers(A,Y) {
         %asm {{
             ldy  #31

compiler/res/prog8lib/pet32/textio.p8

@@ -15,26 +15,6 @@ const ubyte DEFAULT_HEIGHT = 25
 extsub $FFD2 = chrout(ubyte character @ A)    ; for consistency. You can also use cbm.CHROUT directly ofcourse. Note: takes a PETSCII encoded character.
 
 
-sub  clear_screen() {
-    chrout(147)
-}
-
-sub cls() {
-    chrout(147)
-}
-
-sub home() {
-    chrout(19)
-}
-
-sub nl() {
-    chrout('\n')
-}
-
-sub spc() {
-    chrout(' ')
-}
-
 sub bell() {
     chrout(7)
 }
@@ -225,20 +205,16 @@ sub  setcc  (ubyte col, ubyte row, ubyte character, ubyte charcolor_ignored)  {
 
 asmsub  plot  (ubyte col @ Y, ubyte row @ X) {
 	%asm  {{
-	    jsr  home
-	    cpy  #0
-	    beq  +
--	    lda  #29
-	    jsr  chrout
-	    dey
-	    bne  -
-+	    cpx  #0
-	    beq  +
--       lda  #17
-        jsr  chrout
-        dex
-        bne  -
-+		rts
+		stx $d8
+		txa
+		asl a
+		tax
+		lda setchr._screenrows,x
+		sta $c4
+		lda setchr._screenrows+1,x
+		sta $c5
+		sty $c6
+		rts
 	}}
 }
 

compiler/res/prog8lib/prog8_funcs.asm

@@ -401,8 +401,17 @@ _loop_hi	ldy  _index_first
 		.pend
 
 
+func_peek   .proc
+	; -- read the byte value on the address in AY, into A
+	sta  P8ZP_SCRATCH_W1
+	sty  P8ZP_SCRATCH_W1+1
+	ldy  #0
+	lda  (P8ZP_SCRATCH_W1),y
+	rts
+	.pend
+
 func_peekw   .proc
-	; -- read the word value on the address in AY
+	; -- read the word value on the address in AY, into AY
 	sta  P8ZP_SCRATCH_W1
 	sty  P8ZP_SCRATCH_W1+1
 	ldy  #0