improved repeat counter vars allocation (re-use var if possible)

(string deduplication is the default again but only for known-const strings, i.e. string literals)

.gitignore

@@ -30,4 +30,4 @@ parsetab.py
 .gradle
 /prog8compiler.jar
 sd*.img
-
+*.d64

.idea/compiler.xml

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="CompilerConfiguration">
+    <option name="BUILD_PROCESS_HEAP_SIZE" value="1200" />
+  </component>
+</project>

LICENSE

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

README.md

@@ -7,9 +7,6 @@ Prog8 - Structured Programming Language for 8-bit 6502/65c02 microprocessors
 
 *Written by Irmen de Jong (irmen@razorvine.net)*
 
-*Software license: GNU GPL 3.0, see file LICENSE*
-
-
 This is a structured programming language for the 8-bit 6502/6510/65c02 microprocessor from the late 1970's and 1980's
 as used in many home computers from that era. It is a medium to low level programming language,
 which aims to provide many conveniences over raw assembly code (even when using a macro assembler).
@@ -19,27 +16,36 @@ Documentation
 Full documentation (syntax reference, how to use the language and the compiler, etc.) can be found at:
 https://prog8.readthedocs.io/
 
+Software license
+----------------
+GNU GPL 3.0, see file LICENSE
+
+- prog8 (the compiler + libraries) is licensed under GNU GPL 3.0
+- *exception:* the resulting files created by running the compiler are free to use in whatever way desired.
+
 
 What does Prog8 provide?
 ------------------------
 
-- big reduction of source code length over raw assembly
+- reduction of source code length over raw assembly
+- fast execution speed due to compilation to native assembly code. It's possible to write certain raster interrupt 'demoscene' effects purely in Prog8.
 - modularity, symbol scoping, subroutines
 - various data types other than just bytes (16-bit words, floats, strings)
-- automatic variable allocations, automatic string and array variables and string sharing
-- subroutines with an input- and output parameter signature
-- no stack frame allocations because parameters and local variables are automatically allocated statically
-- constant folding in expressions and other high-level program optimizations
+- floating point math is supported if the target system provides floating point library routines (C64 and Cx16 both do)
+- strings can contain escaped characters but also many symbols directly if they have a petscii equivalent, such as "♠♥♣♦π▚●○╳". Characters like ^, _, \, {, } and | are also accepted and converted to the closest petscii equivalents.
+- automatic static variable allocations, automatic string and array variables and string sharing
+- subroutines with input parameters and result values
+- high-level program optimizations
+- small program boilerplate/compilersupport overhead
+- programs can be run multiple times without reloading because of automatic variable (re)initializations.
 - conditional branches
-- floating point operations  (requires the C64 Basic ROM routines for this)
 - 'when' statement to provide a concise jump table alternative to if/elseif chains
-- structs to group together sets of variables and manipulate them at once
 - many built-in functions such as ``sin``, ``cos``, ``rnd``, ``abs``, ``min``, ``max``, ``sqrt``, ``msb``, ``rol``, ``ror``, ``swap``, ``sort`` and ``reverse``
 - various powerful built-in libraries to do I/O, number conversions, graphics and more  
 - convenience abstractions for low level aspects such as ZeroPage handling, program startup, explicit memory addresses
-- fast execution speed due to compilation to native assembly code
 - inline assembly allows you to have full control when every cycle or byte matters
-- supports the sixteen 'virtual' 16-bit registers R0 .. R15 from the Commander X16, and provides them also on the C64.
+- supports the sixteen 'virtual' 16-bit registers R0 - R15 from the Commander X16, and provides them also on the C64.
+- encode strings and characters into petscii or screencodes as desired (C64/Cx16)
 
 *Rapid edit-compile-run-debug cycle:*
 

compiler/build.gradle

@@ -1,8 +1,7 @@
 plugins {
     id 'java'
     id 'application'
-    id "org.jetbrains.kotlin.jvm" version "1.4.30"
-    id 'org.jetbrains.dokka' version "0.9.18"
+    id "org.jetbrains.kotlin.jvm" version "1.5.10"
     id 'com.github.johnrengelman.shadow' version '6.1.0'
 }
 
@@ -21,7 +20,7 @@ dependencies {
     implementation project(':compilerAst')
     implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8"
     // implementation "org.jetbrains.kotlin:kotlin-reflect"
-    implementation 'org.jetbrains.kotlinx:kotlinx-cli:0.3.1'
+    implementation 'org.jetbrains.kotlinx:kotlinx-cli:0.3.2'
     // implementation 'net.razorvine:ksim65:1.8'
     // implementation "com.github.hypfvieh:dbus-java:3.2.4"
 
@@ -97,11 +96,6 @@ test {
 }
 
 
-dokka {
-    outputFormat = 'html'
-    outputDirectory = "$buildDir/kdoc"
-}
-
 task wrapper(type: Wrapper) {
     gradleVersion = '6.7'
 }

compiler/compiler.iml

@@ -1,5 +1,10 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <module type="JAVA_MODULE" version="4">
+  <component name="FacetManager">
+    <facet type="Python" name="Python">
+      <configuration sdkName="Python 3.9" />
+    </facet>
+  </component>
   <component name="NewModuleRootManager" inherit-compiler-output="true">
     <exclude-output />
     <content url="file://$MODULE_DIR$">
@@ -14,5 +19,6 @@
     <orderEntry type="library" name="unittest-libs" level="project" />
     <orderEntry type="library" name="kotlinx-cli-jvm" level="project" />
     <orderEntry type="module" module-name="compilerAst" />
+    <orderEntry type="library" name="Python 3.9 interpreter library" level="application" />
   </component>
 </module>

compiler/res/prog8lib/c64/floats.asm

@@ -428,7 +428,9 @@ var_fac1_greater_f	.proc
 		cmp  #1
 		beq  +
 		lda  #0
-+		rts
+		rts
++		lda  #1
+		rts
 		.pend
 
 var_fac1_greatereq_f	.proc

compiler/res/prog8lib/c64/floats.p8

@@ -83,7 +83,7 @@ romsub $bc58 = ABS()                                        ; fac1 = ABS(fac1)
 romsub $bf71 = SQR() clobbers(A,X,Y)                        ; fac1 = SQRT(fac1)
 romsub $bf74 = SQRA() clobbers(A,X,Y)                       ; fac1 = SQRT(fac2)
 romsub $bfed = EXP() clobbers(A,X,Y)                        ; fac1 = EXP(fac1)  (e ** fac1)
-romsub $bfb4 = NEGOP() clobbers(A)                          ; switch the sign of fac1
+romsub $bfb4 = NEGOP() clobbers(A)                          ; switch the sign of fac1 (fac1 = -fac1)
 romsub $e097 = RND() clobbers(A,X,Y)                        ; fac1 = RND(fac1) float random number generator
 romsub $e264 = COS() clobbers(A,X,Y)                        ; fac1 = COS(fac1)
 romsub $e26b = SIN() clobbers(A,X,Y)                        ; fac1 = SIN(fac1)
@@ -195,7 +195,7 @@ sub  print_f  (float value) {
 	}}
 }
 
-%asminclude "library:c64/floats.asm", ""
-%asminclude "library:c64/floats_funcs.asm", ""
+%asminclude "library:c64/floats.asm"
+%asminclude "library:c64/floats_funcs.asm"
 
 }

compiler/res/prog8lib/c64/graphics.p8

@@ -2,7 +2,7 @@
 %import textio
 
 ; bitmap pixel graphics module for the C64
-; only black/white monchrome 320x200 for now
+; only black/white monochrome 320x200 for now
 ; assumes bitmap screen memory is $2000-$3fff
 
 graphics {
@@ -34,36 +34,33 @@ graphics {
     sub line(uword @zp x1, ubyte @zp y1, uword @zp x2, ubyte @zp y2) {
         ; Bresenham algorithm.
         ; This code special-cases various quadrant loops to allow simple ++ and -- operations.
-        ; TODO there are some slight errors at the first/last pixels in certain slopes...??
         if y1>y2 {
             ; make sure dy is always positive to have only 4 instead of 8 special cases
             swap(x1, x2)
             swap(y1, y2)
         }
-        word @zp dx = x2-x1 as word
-        word @zp dy = y2-y1
+        word @zp dx = (x2 as word)-x1
+        word @zp dy = (y2 as word)-y1
 
         if dx==0 {
-            vertical_line(x1, y1, abs(dy)+1 as ubyte)
+            vertical_line(x1, y1, abs(dy) as ubyte +1)
             return
         }
         if dy==0 {
             if x1>x2
                 x1=x2
-            horizontal_line(x1, y1, abs(dx)+1 as uword)
+            horizontal_line(x1, y1, abs(dx) as uword +1)
             return
         }
 
-        ; TODO rewrite the rest in optimized assembly
-
         word @zp d = 0
         ubyte positive_ix = true
         if dx < 0 {
             dx = -dx
             positive_ix = false
         }
-        dx *= 2
-        dy *= 2
+        word @zp dx2 = dx*2
+        word @zp dy2 = dy*2
         internal_plotx = x1
 
         if dx >= dy {
@@ -73,10 +70,10 @@ graphics {
                     if internal_plotx==x2
                         return
                     internal_plotx++
-                    d += dy
+                    d += dy2
                     if d > dx {
                         y1++
-                        d -= dx
+                        d -= dx2
                     }
                 }
             } else {
@@ -85,10 +82,10 @@ graphics {
                     if internal_plotx==x2
                         return
                     internal_plotx--
-                    d += dy
+                    d += dy2
                     if d > dx {
                         y1++
-                        d -= dx
+                        d -= dx2
                     }
                 }
             }
@@ -100,10 +97,10 @@ graphics {
                     if y1 == y2
                         return
                     y1++
-                    d += dx
+                    d += dx2
                     if d > dy {
                         internal_plotx++
-                        d -= dy
+                        d -= dy2
                     }
                 }
             } else {
@@ -112,10 +109,10 @@ graphics {
                     if y1 == y2
                         return
                     y1++
-                    d += dx
+                    d += dx2
                     if d > dy {
                         internal_plotx--
-                        d -= dy
+                        d -= dy2
                     }
                 }
             }

compiler/res/prog8lib/c64/syslib.p8

@@ -202,7 +202,7 @@ romsub $FFAE = UNLSN() clobbers(A)                              ; command serial
 romsub $FFB1 = LISTEN(ubyte device @ A) clobbers(A)             ; command serial bus device to LISTEN
 romsub $FFB4 = TALK(ubyte device @ A) clobbers(A)               ; command serial bus device to TALK
 romsub $FFB7 = READST() -> ubyte @ A                            ; read I/O status word
-romsub $FFBA = SETLFS(ubyte logical @ A, ubyte device @ X, ubyte address @ Y)   ; set logical file parameters
+romsub $FFBA = SETLFS(ubyte logical @ A, ubyte device @ X, ubyte secondary @ Y)   ; set logical file parameters
 romsub $FFBD = SETNAM(ubyte namelen @ A, str filename @ XY)     ; set filename parameters
 romsub $FFC0 = OPEN() clobbers(X,Y) -> ubyte @Pc, ubyte @A      ; (via 794 ($31A)) open a logical file
 romsub $FFC3 = CLOSE(ubyte logical @ A) clobbers(A,X,Y)         ; (via 796 ($31C)) close a logical file
@@ -211,10 +211,10 @@ romsub $FFC9 = CHKOUT(ubyte logical @ X) clobbers(A,X)          ; (via 800 ($320
 romsub $FFCC = CLRCHN() clobbers(A,X)                           ; (via 802 ($322)) restore default devices
 romsub $FFCF = CHRIN() clobbers(X, Y) -> ubyte @ A   ; (via 804 ($324)) input a character (for keyboard, read a whole line from the screen) A=byte read.
 romsub $FFD2 = CHROUT(ubyte char @ A)                           ; (via 806 ($326)) output a character
-romsub $FFD5 = LOAD(ubyte verify @ A, uword address @ XY) -> ubyte @Pc, ubyte @ A, ubyte @ X, ubyte @ Y     ; (via 816 ($330)) load from device
-romsub $FFD8 = SAVE(ubyte zp_startaddr @ A, uword endaddr @ XY) -> ubyte @ Pc, ubyte @ A                    ; (via 818 ($332)) save to a device
+romsub $FFD5 = LOAD(ubyte verify @ A, uword address @ XY) -> ubyte @Pc, ubyte @ A, uword @ XY     ; (via 816 ($330)) load from device
+romsub $FFD8 = SAVE(ubyte zp_startaddr @ A, uword endaddr @ XY) -> ubyte @ Pc, ubyte @ A          ; (via 818 ($332)) save to a device
 romsub $FFDB = SETTIM(ubyte low @ A, ubyte middle @ X, ubyte high @ Y)      ; set the software clock
-romsub $FFDE = RDTIM() -> ubyte @ A, ubyte @ X, ubyte @ Y       ; read the software clock
+romsub $FFDE = RDTIM() -> ubyte @ A, ubyte @ X, ubyte @ Y       ; read the software clock (A=lo,X=mid,Y=high)
 romsub $FFE1 = STOP() clobbers(X) -> ubyte @ Pz, ubyte @ A      ; (via 808 ($328)) check the STOP key (and some others in A)
 romsub $FFE4 = GETIN() clobbers(X,Y) -> ubyte @Pc, ubyte @ A    ; (via 810 ($32A)) get a character
 romsub $FFE7 = CLALL() clobbers(A,X)                            ; (via 812 ($32C)) close all files
@@ -246,7 +246,7 @@ asmsub STOP2() -> ubyte @A  {
 }
 
 asmsub RDTIM16() -> uword @AY {
-    ; --  like RDTIM() but only returning the lower 16 bits for convenience
+    ; --  like RDTIM() but only returning the lower 16 bits in AY for convenience
     %asm {{
         stx  P8ZP_SCRATCH_REG
         jsr  c64.RDTIM
@@ -478,7 +478,7 @@ sys {
 
 
     asmsub  reset_system()  {
-        ; Soft-reset the system back to Basic prompt.
+        ; Soft-reset the system back to initial power-on Basic prompt.
         %asm {{
             sei
             lda  #14
@@ -489,6 +489,7 @@ sys {
 
     sub wait(uword jiffies) {
         ; --- wait approximately the given number of jiffies (1/60th seconds)
+        ;     note: the system irq handler has to be active for this to work as it depends on the system jiffy clock
         repeat jiffies {
             ubyte jiff = lsb(c64.RDTIM16())
             while jiff==lsb(c64.RDTIM16()) {
@@ -497,6 +498,29 @@ sys {
         }
     }
 
+    asmsub waitvsync() clobbers(A) {
+        ; --- busy wait till the next vsync has occurred (approximately), without depending on custom irq handling.
+        ;     note: a more accurate way to wait for vsync is to set up a vsync irq handler instead.
+        %asm {{
+-           lda  c64.RASTER
+            beq  -
+-           lda  c64.RASTER
+            bne  -
+            bit  c64.SCROLY
+            bmi  -
+            rts
+        }}
+    }
+
+    inline asmsub waitrastborder() {
+        ; --- busy wait till the raster position has reached the bottom screen border (approximately)
+        ;     note: a more accurate way to do this is by using a raster irq handler instead.
+        %asm {{
+-           bit  c64.SCROLY
+            bpl  -
+        }}
+    }
+
     asmsub memcopy(uword source @R0, uword target @R1, uword count @AY) clobbers(A,X,Y) {
         %asm {{
             ldx  cx16.r0
@@ -679,4 +703,37 @@ cx16 {
     &uword r14 = $cf1c
     &uword r15 = $cf1e
 
+    &ubyte r0L  = $cf00
+    &ubyte r1L  = $cf02
+    &ubyte r2L  = $cf04
+    &ubyte r3L  = $cf06
+    &ubyte r4L  = $cf08
+    &ubyte r5L  = $cf0a
+    &ubyte r6L  = $cf0c
+    &ubyte r7L  = $cf0e
+    &ubyte r8L  = $cf10
+    &ubyte r9L  = $cf12
+    &ubyte r10L = $cf14
+    &ubyte r11L = $cf16
+    &ubyte r12L = $cf18
+    &ubyte r13L = $cf1a
+    &ubyte r14L = $cf1c
+    &ubyte r15L = $cf1e
+
+    &ubyte r0H  = $cf01
+    &ubyte r1H  = $cf03
+    &ubyte r2H  = $cf05
+    &ubyte r3H  = $cf07
+    &ubyte r4H  = $cf09
+    &ubyte r5H  = $cf0b
+    &ubyte r6H  = $cf0d
+    &ubyte r7H  = $cf0f
+    &ubyte r8H  = $cf11
+    &ubyte r9H  = $cf13
+    &ubyte r10H = $cf15
+    &ubyte r11H = $cf17
+    &ubyte r12H = $cf19
+    &ubyte r13H = $cf1b
+    &ubyte r14H = $cf1d
+    &ubyte r15H = $cf1f
 }

compiler/res/prog8lib/conv.p8

@@ -7,239 +7,213 @@ conv {
 
 ; ----- number conversions to decimal strings ----
 
-asmsub  ubyte2decimal  (ubyte value @A) -> ubyte @Y, ubyte @A, ubyte @X  {
-	; ---- A to decimal string in Y/A/X  (100s in Y, 10s in A, 1s in X)
+    str  string_out = "????????????????"       ; result buffer for the string conversion routines
+
+asmsub  str_ub0  (ubyte value @ A) clobbers(A,Y)  {
+	; ---- convert the ubyte in A in decimal string form, with left padding 0s (3 positions total)
 	%asm {{
-		ldy  #uword2decimal.ASCII_0_OFFSET
-		bne  uword2decimal.hex_try200
-		rts
+            phx
+            jsr  conv.ubyte2decimal
+            sty  string_out
+            sta  string_out+1
+            stx  string_out+2
+            lda  #0
+            sta  string_out+3
+            plx
+            rts
 	}}
 }
 
-asmsub  uword2decimal  (uword value @AY) -> ubyte @Y, ubyte @A, ubyte @X  {
-	;  ---- convert 16 bit uword in A/Y to decimal
-	;  output in uword2decimal.decTenThousands, decThousands, decHundreds, decTens, decOnes
-	;  (these are terminated by a zero byte so they can be easily printed)
-	;  also returns Y = 100's, A = 10's, X = 1's
-
+asmsub  str_ub  (ubyte value @ A) clobbers(A,Y)  {
+	; ---- convert the ubyte in A in decimal string form, without left padding 0s
 	%asm {{
-
-;Convert 16 bit Hex to Decimal (0-65535) Rev 2
-;By Omegamatrix    Further optimizations by tepples
-; routine from http://forums.nesdev.com/viewtopic.php?f=2&t=11341&start=15
-
-;HexToDec99
-; start in A
-; end with A = 10's, decOnes (also in X)
-
-;HexToDec255
-; start in A
-; end with Y = 100's, A = 10's, decOnes (also in X)
-
-;HexToDec999
-; start with A = high byte, Y = low byte
-; end with Y = 100's, A = 10's, decOnes (also in X)
-; requires 1 extra temp register on top of decOnes, could combine
-; these two if HexToDec65535 was eliminated...
-
-;HexToDec65535
-; start with A/Y (low/high) as 16 bit value
-; end with decTenThousand, decThousand, Y = 100's, A = 10's, decOnes (also in X)
-; (irmen: I store Y and A in decHundreds and decTens too, so all of it can be easily printed)
-
-
-ASCII_0_OFFSET 	= $30
-temp       	    = P8ZP_SCRATCH_B1	; byte in zeropage
-hexHigh      	= P8ZP_SCRATCH_W1	; byte in zeropage
-hexLow       	= P8ZP_SCRATCH_W1+1	; byte in zeropage
-
-
-HexToDec65535; SUBROUTINE
-    sty    hexHigh               ;3  @9
-    sta    hexLow                ;3  @12
-    tya
-    tax                          ;2  @14
-    lsr    a                     ;2  @16
-    lsr    a                     ;2  @18   integer divide 1024 (result 0-63)
-
-    cpx    #$A7                  ;2  @20   account for overflow of multiplying 24 from 43,000 ($A7F8) onward,
-    adc    #1                    ;2  @22   we can just round it to $A700, and the divide by 1024 is fine...
-
-    ;at this point we have a number 1-65 that we have to times by 24,
-    ;add to original sum, and Mod 1024 to get a remainder 0-999
-
-
-    sta    temp                  ;3  @25
-    asl    a                     ;2  @27
-    adc    temp                  ;3  @30  x3
-    tay                          ;2  @32
-    lsr    a                     ;2  @34
-    lsr    a                     ;2  @36
-    lsr    a                     ;2  @38
-    lsr    a                     ;2  @40
-    lsr    a                     ;2  @42
-    tax                          ;2  @44
-    tya                          ;2  @46
-    asl    a                     ;2  @48
-    asl    a                     ;2  @50
-    asl    a                     ;2  @52
-    clc                          ;2  @54
-    adc    hexLow                ;3  @57
-    sta    hexLow                ;3  @60
-    txa                          ;2  @62
-    adc    hexHigh               ;3  @65
-    sta    hexHigh               ;3  @68
-    ror    a                     ;2  @70
-    lsr    a                     ;2  @72
-    tay                          ;2  @74    integer divide 1,000 (result 0-65)
-
-    lsr    a                     ;2  @76    split the 1,000 and 10,000 digit
-    tax                          ;2  @78
-    lda    ShiftedBcdTab,x       ;4  @82
-    tax                          ;2  @84
-    rol    a                     ;2  @86
-    and    #$0F                  ;2  @88
-    ora    #ASCII_0_OFFSET
-    sta    decThousands          ;3  @91
-    txa                          ;2  @93
-    lsr    a                     ;2  @95
-    lsr    a                     ;2  @97
-    lsr    a                     ;2  @99
-    ora    #ASCII_0_OFFSET
-    sta    decTenThousands       ;3  @102
-
-    lda    hexLow                ;3  @105
-    cpy    temp                  ;3  @108
-    bmi    _doSubtract           ;2³ @110/111
-    beq    _useZero               ;2³ @112/113
-    adc    #23 + 24              ;2  @114
-_doSubtract
-    sbc    #23                   ;2  @116
-    sta    hexLow                ;3  @119
-_useZero
-    lda    hexHigh               ;3  @122
-    sbc    #0                    ;2  @124
-
-Start100s
-    and    #$03                  ;2  @126
-    tax                          ;2  @128   0,1,2,3
-    cmp    #2                    ;2  @130
-    rol    a                     ;2  @132   0,2,5,7
-    ora    #ASCII_0_OFFSET
-    tay                          ;2  @134   Y = Hundreds digit
-
-    lda    hexLow                ;3  @137
-    adc    Mod100Tab,x           ;4  @141    adding remainder of 256, 512, and 256+512 (all mod 100)
-    bcs    hex_doSub200             ;2³ @143/144
-
-hex_try200
-    cmp    #200                  ;2  @145
-    bcc    hex_try100               ;2³ @147/148
-hex_doSub200
-    iny                          ;2  @149
-    iny                          ;2  @151
-    sbc    #200                  ;2  @153
-hex_try100
-    cmp    #100                  ;2  @155
-    bcc    HexToDec99            ;2³ @157/158
-    iny                          ;2  @159
-    sbc    #100                  ;2  @161
-
-HexToDec99; SUBROUTINE
-    lsr    a                     ;2  @163
-    tax                          ;2  @165
-    lda    ShiftedBcdTab,x       ;4  @169
-    tax                          ;2  @171
-    rol    a                     ;2  @173
-    and    #$0F                  ;2  @175
-    ora    #ASCII_0_OFFSET
-    sta    decOnes               ;3  @178
-    txa                          ;2  @180
-    lsr    a                     ;2  @182
-    lsr    a                     ;2  @184
-    lsr    a                     ;2  @186
-    ora    #ASCII_0_OFFSET
-
-    ; irmen: load X with ones, and store Y and A too, for easy printing afterwards
-    sty  decHundreds
-    sta  decTens
-    ldx  decOnes
-    rts                          ;6  @192   Y=hundreds, A = tens digit, X=ones digit
-
-
-HexToDec999; SUBROUTINE
-    sty    hexLow                ;3  @9
-    jmp    Start100s             ;3  @12
-
-Mod100Tab
-    .byte 0,56,12,56+12
-
-ShiftedBcdTab
-    .byte $00,$01,$02,$03,$04,$08,$09,$0A,$0B,$0C
-    .byte $10,$11,$12,$13,$14,$18,$19,$1A,$1B,$1C
-    .byte $20,$21,$22,$23,$24,$28,$29,$2A,$2B,$2C
-    .byte $30,$31,$32,$33,$34,$38,$39,$3A,$3B,$3C
-    .byte $40,$41,$42,$43,$44,$48,$49,$4A,$4B,$4C
-
-decTenThousands   	.byte  0
-decThousands    	.byte  0
-decHundreds		.byte  0
-decTens			.byte  0
-decOnes   		.byte  0
-			.byte  0		; zero-terminate the decimal output string
-
-    }}
-}
-
-asmsub  byte2decimal  (byte value @A) -> ubyte @Y, ubyte @A, ubyte @X  {
-	; ---- A (signed byte) to decimal string in Y/A/X  (100s in Y, 10s in A, 1s in X)
-	;      note: if the number is negative, you have to deal with the '-' yourself!
-	%asm {{
-		cmp  #0
-		bpl  +
-		eor  #255
-		clc
-		adc  #1
-+		jmp  ubyte2decimal
-	}}
-}
-
-asmsub  ubyte2hex  (ubyte value @A) -> ubyte @A, ubyte @Y  {
-	; ---- A to hex petscii string in AY (first hex char in A, second hex char in Y)
-	%asm {{
-		stx  P8ZP_SCRATCH_REG
+		phx
+		ldy  #0
+		sty  P8ZP_SCRATCH_B1
+		jsr  conv.ubyte2decimal
+_output_byte_digits
+                ; hundreds?
+		cpy  #'0'
+		beq  +
 		pha
-		and  #$0f
-		tax
-		ldy  _hex_digits,x
+		tya
+		ldy  P8ZP_SCRATCH_B1
+		sta  string_out,y
 		pla
-		lsr  a
-		lsr  a
-		lsr  a
-		lsr  a
-		tax
-		lda  _hex_digits,x
-		ldx  P8ZP_SCRATCH_REG
-		rts
-
-_hex_digits	.text "0123456789abcdef"	; can probably be reused for other stuff as well
+		inc  P8ZP_SCRATCH_B1
+		; tens?
++		ldy  P8ZP_SCRATCH_B1
+                cmp  #'0'
+		beq  +
+		sta  string_out,y
+		iny
++               ; ones.
+                txa
+                sta  string_out,y
+                iny
+                lda  #0
+                sta  string_out,y
+                plx
+                rts
 	}}
 }
 
-asmsub  uword2hex  (uword value @AY) clobbers(A,Y)  {
-	; ---- convert 16 bit uword in A/Y into 4-character hexadecimal string 'uword2hex.output' (0-terminated)
+asmsub  str_b  (byte value @ A) clobbers(A,Y)  {
+	; ---- convert the byte in A in decimal string form, without left padding 0s
 	%asm {{
-		sta  P8ZP_SCRATCH_REG
-		tya
-		jsr  ubyte2hex
-		sta  output
-		sty  output+1
-		lda  P8ZP_SCRATCH_REG
-		jsr  ubyte2hex
-		sta  output+2
-		sty  output+3
-		rts
-output		.text  "0000", $00      ; 0-terminated output buffer (to make printing easier)
+            phx
+            ldy  #0
+            sty  P8ZP_SCRATCH_B1
+            cmp  #0
+            bpl  +
+            pha
+            lda  #'-'
+            sta  string_out
+            inc  P8ZP_SCRATCH_B1
+            pla
++	    jsr  conv.byte2decimal
+            bra  str_ub._output_byte_digits
+	}}
+}
+
+asmsub  str_ubhex  (ubyte value @ A) clobbers(A,Y)  {
+	; ---- convert the ubyte in A in hex string form
+	%asm {{
+            jsr  conv.ubyte2hex
+            sta  string_out
+            sty  string_out+1
+            lda  #0
+            sta  string_out+2
+            rts
+	}}
+}
+
+asmsub  str_ubbin  (ubyte value @ A) clobbers(A,Y)  {
+	; ---- convert the ubyte in A in binary string form
+	%asm {{
+	    sta  P8ZP_SCRATCH_B1
+	    ldy  #0
+	    sty  string_out+8
+	    ldy  #7
+-	    lsr  P8ZP_SCRATCH_B1
+            bcc  +
+            lda  #'1'
+            bne  _digit
++           lda  #'0'
+_digit      sta  string_out,y
+            dey
+	    bpl  -
+	    rts
+	}}
+}
+
+asmsub  str_uwbin  (uword value @ AY) clobbers(A,Y)  {
+	; ---- convert the uword in A/Y in binary string form
+	%asm {{
+	    sta  P8ZP_SCRATCH_REG
+	    tya
+	    jsr  str_ubbin
+	    ldy  #0
+	    sty  string_out+16
+	    ldy  #7
+-	    lsr  P8ZP_SCRATCH_REG
+            bcc  +
+            lda  #'1'
+            bne  _digit
++           lda  #'0'
+_digit      sta  string_out+8,y
+            dey
+	    bpl  -
+	    rts
+	}}
+}
+
+asmsub  str_uwhex  (uword value @ AY) clobbers(A,Y)  {
+	; ---- convert the uword in A/Y in hexadecimal string form (4 digits)
+	%asm {{
+            pha
+            tya
+            jsr  conv.ubyte2hex
+            sta  string_out
+            sty  string_out+1
+            pla
+            jsr  conv.ubyte2hex
+            sta  string_out+2
+            sty  string_out+3
+            lda  #0
+            sta  string_out+4
+            rts
+	}}
+}
+
+asmsub  str_uw0  (uword value @ AY) clobbers(A,Y)  {
+	; ---- convert the uword in A/Y in decimal string form, with left padding 0s (5 positions total)
+	%asm {{
+	    phx
+	    jsr  conv.uword2decimal
+	    ldy  #0
+-           lda  conv.uword2decimal.decTenThousands,y
+            sta  string_out,y
+            beq  +
+            iny
+            bne  -
++           plx
+	    rts
+	}}
+}
+
+asmsub  str_uw  (uword value @ AY) clobbers(A,Y)  {
+	; ---- convert the uword in A/Y in decimal string form, without left padding 0s
+	%asm {{
+	    phx
+	    jsr  conv.uword2decimal
+	    ldx  #0
+_output_digits
+	    ldy  #0
+-           lda  conv.uword2decimal.decTenThousands,y
+            beq  _allzero
+            cmp  #'0'
+            bne  _gotdigit
+            iny
+            bne  -
+_gotdigit   sta  string_out,x
+            inx
+            iny
+            lda  conv.uword2decimal.decTenThousands,y
+            bne  _gotdigit
+_end        lda  #0
+            sta  string_out,x
+            plx
+            rts
+
+_allzero    lda  #'0'
+            sta  string_out,x
+            inx
+            bne  _end
+	}}
+}
+
+asmsub  str_w  (word value @ AY) clobbers(A,Y)  {
+	; ---- convert the (signed) word in A/Y in decimal string form, without left padding 0's
+	%asm {{
+	    cpy  #0
+	    bpl  str_uw
+	    phx
+	    pha
+	    lda  #'-'
+	    sta  string_out
+            tya
+            eor  #255
+            tay
+            pla
+            eor  #255
+            clc
+            adc  #1
+            bcc  +
+            iny
++	    jsr  conv.uword2decimal
+	    ldx  #1
+	    bne  str_uw._output_digits
 	}}
 }
 
@@ -520,4 +494,243 @@ _stop
 	}}
 }
 
+
+; ----- low level number conversions to decimal strings ----
+
+asmsub  ubyte2decimal  (ubyte value @A) -> ubyte @Y, ubyte @A, ubyte @X  {
+	; ---- A to decimal string in Y/A/X  (100s in Y, 10s in A, 1s in X)
+	%asm {{
+		ldy  #uword2decimal.ASCII_0_OFFSET
+		bne  uword2decimal.hex_try200
+		rts
+	}}
+}
+
+asmsub  uword2decimal  (uword value @AY) -> ubyte @Y, ubyte @A, ubyte @X  {
+	;  ---- convert 16 bit uword in A/Y to decimal
+	;  output in uword2decimal.decTenThousands, decThousands, decHundreds, decTens, decOnes
+	;  (these are terminated by a zero byte so they can be easily printed)
+	;  also returns Y = 100's, A = 10's, X = 1's
+
+	%asm {{
+
+;Convert 16 bit Hex to Decimal (0-65535) Rev 2
+;By Omegamatrix    Further optimizations by tepples
+; routine from http://forums.nesdev.com/viewtopic.php?f=2&t=11341&start=15
+
+;HexToDec99
+; start in A
+; end with A = 10's, decOnes (also in X)
+
+;HexToDec255
+; start in A
+; end with Y = 100's, A = 10's, decOnes (also in X)
+
+;HexToDec999
+; start with A = high byte, Y = low byte
+; end with Y = 100's, A = 10's, decOnes (also in X)
+; requires 1 extra temp register on top of decOnes, could combine
+; these two if HexToDec65535 was eliminated...
+
+;HexToDec65535
+; start with A/Y (low/high) as 16 bit value
+; end with decTenThousand, decThousand, Y = 100's, A = 10's, decOnes (also in X)
+; (irmen: I store Y and A in decHundreds and decTens too, so all of it can be easily printed)
+
+
+ASCII_0_OFFSET 	= $30
+temp       	    = P8ZP_SCRATCH_B1	; byte in zeropage
+hexHigh      	= P8ZP_SCRATCH_W1	; byte in zeropage
+hexLow       	= P8ZP_SCRATCH_W1+1	; byte in zeropage
+
+
+HexToDec65535; SUBROUTINE
+    sty    hexHigh               ;3  @9
+    sta    hexLow                ;3  @12
+    tya
+    tax                          ;2  @14
+    lsr    a                     ;2  @16
+    lsr    a                     ;2  @18   integer divide 1024 (result 0-63)
+
+    cpx    #$A7                  ;2  @20   account for overflow of multiplying 24 from 43,000 ($A7F8) onward,
+    adc    #1                    ;2  @22   we can just round it to $A700, and the divide by 1024 is fine...
+
+    ;at this point we have a number 1-65 that we have to times by 24,
+    ;add to original sum, and Mod 1024 to get a remainder 0-999
+
+
+    sta    temp                  ;3  @25
+    asl    a                     ;2  @27
+    adc    temp                  ;3  @30  x3
+    tay                          ;2  @32
+    lsr    a                     ;2  @34
+    lsr    a                     ;2  @36
+    lsr    a                     ;2  @38
+    lsr    a                     ;2  @40
+    lsr    a                     ;2  @42
+    tax                          ;2  @44
+    tya                          ;2  @46
+    asl    a                     ;2  @48
+    asl    a                     ;2  @50
+    asl    a                     ;2  @52
+    clc                          ;2  @54
+    adc    hexLow                ;3  @57
+    sta    hexLow                ;3  @60
+    txa                          ;2  @62
+    adc    hexHigh               ;3  @65
+    sta    hexHigh               ;3  @68
+    ror    a                     ;2  @70
+    lsr    a                     ;2  @72
+    tay                          ;2  @74    integer divide 1,000 (result 0-65)
+
+    lsr    a                     ;2  @76    split the 1,000 and 10,000 digit
+    tax                          ;2  @78
+    lda    ShiftedBcdTab,x       ;4  @82
+    tax                          ;2  @84
+    rol    a                     ;2  @86
+    and    #$0F                  ;2  @88
+    ora    #ASCII_0_OFFSET
+    sta    decThousands          ;3  @91
+    txa                          ;2  @93
+    lsr    a                     ;2  @95
+    lsr    a                     ;2  @97
+    lsr    a                     ;2  @99
+    ora    #ASCII_0_OFFSET
+    sta    decTenThousands       ;3  @102
+
+    lda    hexLow                ;3  @105
+    cpy    temp                  ;3  @108
+    bmi    _doSubtract           ;2³ @110/111
+    beq    _useZero               ;2³ @112/113
+    adc    #23 + 24              ;2  @114
+_doSubtract
+    sbc    #23                   ;2  @116
+    sta    hexLow                ;3  @119
+_useZero
+    lda    hexHigh               ;3  @122
+    sbc    #0                    ;2  @124
+
+Start100s
+    and    #$03                  ;2  @126
+    tax                          ;2  @128   0,1,2,3
+    cmp    #2                    ;2  @130
+    rol    a                     ;2  @132   0,2,5,7
+    ora    #ASCII_0_OFFSET
+    tay                          ;2  @134   Y = Hundreds digit
+
+    lda    hexLow                ;3  @137
+    adc    Mod100Tab,x           ;4  @141    adding remainder of 256, 512, and 256+512 (all mod 100)
+    bcs    hex_doSub200             ;2³ @143/144
+
+hex_try200
+    cmp    #200                  ;2  @145
+    bcc    hex_try100               ;2³ @147/148
+hex_doSub200
+    iny                          ;2  @149
+    iny                          ;2  @151
+    sbc    #200                  ;2  @153
+hex_try100
+    cmp    #100                  ;2  @155
+    bcc    HexToDec99            ;2³ @157/158
+    iny                          ;2  @159
+    sbc    #100                  ;2  @161
+
+HexToDec99; SUBROUTINE
+    lsr    a                     ;2  @163
+    tax                          ;2  @165
+    lda    ShiftedBcdTab,x       ;4  @169
+    tax                          ;2  @171
+    rol    a                     ;2  @173
+    and    #$0F                  ;2  @175
+    ora    #ASCII_0_OFFSET
+    sta    decOnes               ;3  @178
+    txa                          ;2  @180
+    lsr    a                     ;2  @182
+    lsr    a                     ;2  @184
+    lsr    a                     ;2  @186
+    ora    #ASCII_0_OFFSET
+
+    ; irmen: load X with ones, and store Y and A too, for easy printing afterwards
+    sty  decHundreds
+    sta  decTens
+    ldx  decOnes
+    rts                          ;6  @192   Y=hundreds, A = tens digit, X=ones digit
+
+
+HexToDec999; SUBROUTINE
+    sty    hexLow                ;3  @9
+    jmp    Start100s             ;3  @12
+
+Mod100Tab
+    .byte 0,56,12,56+12
+
+ShiftedBcdTab
+    .byte $00,$01,$02,$03,$04,$08,$09,$0A,$0B,$0C
+    .byte $10,$11,$12,$13,$14,$18,$19,$1A,$1B,$1C
+    .byte $20,$21,$22,$23,$24,$28,$29,$2A,$2B,$2C
+    .byte $30,$31,$32,$33,$34,$38,$39,$3A,$3B,$3C
+    .byte $40,$41,$42,$43,$44,$48,$49,$4A,$4B,$4C
+
+decTenThousands   	.byte  0
+decThousands    	.byte  0
+decHundreds		.byte  0
+decTens			.byte  0
+decOnes   		.byte  0
+			.byte  0		; zero-terminate the decimal output string
+
+    }}
+}
+
+asmsub  byte2decimal  (byte value @A) -> ubyte @Y, ubyte @A, ubyte @X  {
+	; ---- A (signed byte) to decimal string in Y/A/X  (100s in Y, 10s in A, 1s in X)
+	;      note: if the number is negative, you have to deal with the '-' yourself!
+	%asm {{
+		cmp  #0
+		bpl  +
+		eor  #255
+		clc
+		adc  #1
++		jmp  ubyte2decimal
+	}}
+}
+
+asmsub  ubyte2hex  (ubyte value @A) -> ubyte @A, ubyte @Y  {
+	; ---- A to hex petscii string in AY (first hex char in A, second hex char in Y)
+	%asm {{
+		stx  P8ZP_SCRATCH_REG
+		pha
+		and  #$0f
+		tax
+		ldy  _hex_digits,x
+		pla
+		lsr  a
+		lsr  a
+		lsr  a
+		lsr  a
+		tax
+		lda  _hex_digits,x
+		ldx  P8ZP_SCRATCH_REG
+		rts
+
+_hex_digits	.text "0123456789abcdef"	; can probably be reused for other stuff as well
+	}}
+}
+
+asmsub  uword2hex  (uword value @AY) clobbers(A,Y)  {
+	; ---- convert 16 bit uword in A/Y into 4-character hexadecimal string 'uword2hex.output' (0-terminated)
+	%asm {{
+		sta  P8ZP_SCRATCH_REG
+		tya
+		jsr  ubyte2hex
+		sta  output
+		sty  output+1
+		lda  P8ZP_SCRATCH_REG
+		jsr  ubyte2hex
+		sta  output+2
+		sty  output+3
+		rts
+output		.text  "0000", $00      ; 0-terminated output buffer (to make printing easier)
+	}}
+}
+
 }

compiler/res/prog8lib/cx16/floats.p8

@@ -8,7 +8,9 @@
 %option enable_floats
 
 floats {
-	; ---- this block contains C-64 floating point related functions ----
+	; ---- this block contains C-64 compatible floating point related functions ----
+	;      the addresses are from cx16 V39 emulator and roms! they won't work on older versions.
+
 
         const float  PI     = 3.141592653589793
         const float  TWOPI  = 6.283185307179586
@@ -43,46 +45,44 @@ romsub $fe1e = NORMAL() clobbers(A,X,Y)                     ; normalize fac1 (?)
 romsub $fe24 = LOG() clobbers(A,X,Y)                        ; fac1 = LN(fac1)  (natural log)
 romsub $fe27 = FMULT(uword mflpt @ AY) clobbers(A,X,Y)      ; fac1 *= mflpt value from A/Y
 romsub $fe2a = FMULTT() clobbers(A,X,Y)                     ; fac1 *= fac2
-romsub $fe33 = CONUPK(uword mflpt @ AY) clobbers(A,Y)       ; load mflpt value from memory  in A/Y into fac2
-romsub $fe36 = MUL10() clobbers(A,X,Y)                      ; fac1 *= 10
-romsub $fe3c = DIV10() clobbers(A,X,Y)                      ; fac1 /= 10 , CAUTION: result is always positive!
-romsub $fe3f = FDIV(uword mflpt @ AY) clobbers(A,X,Y)       ; fac1 = mflpt in A/Y / fac1  (remainder in fac2)
-romsub $fe42 = FDIVT() clobbers(A,X,Y)                      ; fac1 = fac2/fac1  (remainder in fac2)  mind the order of the operands
+romsub $fe30 = CONUPK(uword mflpt @ AY) clobbers(A,X,Y)     ; load mflpt value from memory  in A/Y into fac2
+romsub $fe33 = MUL10() clobbers(A,X,Y)                      ; fac1 *= 10
+romsub $fe36 = DIV10() clobbers(A,X,Y)                      ; fac1 /= 10 , CAUTION: result is always positive!
+romsub $fe39 = FDIV(uword mflpt @ AY) clobbers(A,X,Y)       ; fac1 = mflpt in A/Y / fac1  (remainder in fac2)
+romsub $fe3c = FDIVT() clobbers(A,X,Y)                      ; fac1 = fac2/fac1  (remainder in fac2)  mind the order of the operands
 
-romsub $fe48 = MOVFM(uword mflpt @ AY) clobbers(A,Y)        ; load mflpt value from memory  in A/Y into fac1
-romsub $fe4b = MOVMF(uword mflpt @ XY) clobbers(A,Y)        ; store fac1 to memory  X/Y as 5-byte mflpt
-romsub $fe4e = MOVFA() clobbers(A,X)                        ; copy fac2 to fac1
-romsub $fe51 = MOVAF() clobbers(A,X)                        ; copy fac1 to fac2  (rounded)
-romsub $fe54 = MOVEF() clobbers(A,X)                        ; copy fac1 to fac2
-romsub $fe5a = SIGN() -> ubyte @ A                          ; SIGN(fac1) to A, $ff, $0, $1 for negative, zero, positive
-romsub $fe5d = SGN() clobbers(A,X,Y)                        ; fac1 = SGN(fac1), result of SIGN (-1, 0 or 1)
-romsub $fe60 = FREADSA(byte value @ A) clobbers(A,X,Y)      ; 8 bit signed A -> float in fac1
-romsub $fe6c = ABS()                                        ; fac1 = ABS(fac1)
-romsub $fe6f = FCOMP(uword mflpt @ AY) clobbers(X,Y) -> ubyte @ A   ; A = compare fac1 to mflpt in A/Y, 0=equal 1=fac1 is greater, 255=fac1 is less than
-romsub $fe78 = INT() clobbers(A,X,Y)                        ; INT() truncates, use FADDH first to round instead of trunc
-romsub $fe7e = FINLOG(byte value @A) clobbers (A, X, Y)           ; fac1 += signed byte in A
-romsub $fe81 = FOUT() clobbers(X) -> uword @ AY             ; fac1 -> string, address returned in AY
-romsub $fe8a = SQR() clobbers(A,X,Y)                        ; fac1 = SQRT(fac1)
-romsub $fe8d = FPWRT() clobbers(A,X,Y)                      ; fac1 = fac2 ** fac1
-; note: there is no FPWR() on the Cx16
-romsub $fe93 = NEGOP() clobbers(A)                          ; switch the sign of fac1
-romsub $fe96 = EXP() clobbers(A,X,Y)                        ; fac1 = EXP(fac1)  (e ** fac1)
-romsub $fe9f = RND2(byte value @A) clobbers(A,X,Y)                ; fac1 = RND(A) float random number generator
-romsub $fea2 = RND() clobbers(A,X,Y)                        ; fac1 = RND(fac1) float random number generator
-romsub $fea5 = COS() clobbers(A,X,Y)                        ; fac1 = COS(fac1)
-romsub $fea8 = SIN() clobbers(A,X,Y)                        ; fac1 = SIN(fac1)
-romsub $feab = TAN() clobbers(A,X,Y)                        ; fac1 = TAN(fac1)
-romsub $feae = ATN() clobbers(A,X,Y)                        ; fac1 = ATN(fac1)
+romsub $fe42 = MOVFM(uword mflpt @ AY) clobbers(A,X,Y)      ; load mflpt value from memory  in A/Y into fac1
+romsub $fe45 = MOVMF(uword mflpt @ XY) clobbers(A,X,Y)      ; store fac1 to memory  X/Y as 5-byte mflpt
+romsub $fe48 = MOVFA() clobbers(A,X)                        ; copy fac2 to fac1
+romsub $fe4b = MOVAF() clobbers(A,X)                        ; copy fac1 to fac2  (rounded)
+romsub $fe4e = MOVEF() clobbers(A,X)                        ; copy fac1 to fac2
+romsub $fe54 = SIGN() clobbers(X,Y) -> ubyte @ A            ; SIGN(fac1) to A, $ff, $0, $1 for negative, zero, positive
+romsub $fe57 = SGN() clobbers(A,X,Y)                        ; fac1 = SGN(fac1), result of SIGN (-1, 0 or 1)
+romsub $fe5a = FREADSA(byte value @ A) clobbers(A,X,Y)      ; 8 bit signed A -> float in fac1
+romsub $fe66 = ABS() clobbers(A,X,Y)                        ; fac1 = ABS(fac1)
+romsub $fe69 = FCOMP(uword mflpt @ AY) clobbers(X,Y) -> ubyte @ A   ; A = compare fac1 to mflpt in A/Y, 0=equal 1=fac1 is greater, 255=fac1 is less than
+romsub $fe72 = INT() clobbers(A,X,Y)                        ; INT() truncates, use FADDH first to round instead of trunc
+romsub $fe78 = FINLOG(byte value @A) clobbers (A, X, Y)           ; fac1 += signed byte in A
+romsub $fe7b = FOUT() clobbers(X) -> uword @ AY             ; fac1 -> string, address returned in AY
+romsub $fe81 = SQR() clobbers(A,X,Y)                        ; fac1 = SQRT(fac1)
+romsub $fe84 = FPWRT() clobbers(A,X,Y)                      ; fac1 = fac2 ** fac1
+romsub $fe8a = NEGOP() clobbers(A)                          ; switch the sign of fac1 (fac1 = -fac1)
+romsub $fe8d = EXP() clobbers(A,X,Y)                        ; fac1 = EXP(fac1)  (e ** fac1)
+romsub $fe96 = RND() clobbers(A,X,Y)                        ; fac1 = RND(fac1) float random number generator
+romsub $fe99 = COS() clobbers(A,X,Y)                        ; fac1 = COS(fac1)
+romsub $fe9c = SIN() clobbers(A,X,Y)                        ; fac1 = SIN(fac1)
+romsub $fe9f = TAN() clobbers(A,X,Y)                        ; fac1 = TAN(fac1)
+romsub $fea2 = ATN() clobbers(A,X,Y)                        ; fac1 = ATN(fac1)
 
 
 asmsub  GIVUAYFAY  (uword value @ AY) clobbers(A,X,Y)  {
 	; ---- unsigned 16 bit word in A/Y (lo/hi) to fac1
 	%asm {{
         phx
-        sta  P8ZP_SCRATCH_W2
+        sta  _tmp
         sty  P8ZP_SCRATCH_B1
         tya
-        ldy  P8ZP_SCRATCH_W2
+        ldy  _tmp
         jsr  GIVAYF                 ; load it as signed... correct afterwards
         lda  P8ZP_SCRATCH_B1
 	    bpl  +
@@ -91,6 +91,7 @@ asmsub  GIVUAYFAY  (uword value @ AY) clobbers(A,X,Y)  {
 	    jsr  FADD
 +	    plx
         rts
+_tmp        .byte 0
 _flt65536    .byte 145,0,0,0,0       ; 65536.0
 	}}
 }
@@ -128,6 +129,14 @@ asmsub  GETADRAY  () clobbers(X) -> uword @ AY  {
 	}}
 }
 
+asmsub  FREADUY (ubyte value @Y) {
+    ; -- 8 bit unsigned Y -> float in fac1
+    %asm {{
+        lda  #0
+        jmp  GIVAYF
+    }}
+}
+
 sub  print_f  (float value) {
 	; ---- prints the floating point value (without a newline).
 	%asm {{
@@ -149,7 +158,7 @@ sub  print_f  (float value) {
 	}}
 }
 
-%asminclude "library:c64/floats.asm", ""
-%asminclude "library:c64/floats_funcs.asm", ""
+%asminclude "library:c64/floats.asm"
+%asminclude "library:c64/floats_funcs.asm"
 
 }

compiler/res/prog8lib/cx16/gfx2.p8

@@ -22,6 +22,7 @@
 ;   mode 6 = bitmap 640 x 480 x 4c
 ;   higher color dephts in highres are not supported due to lack of VRAM
 
+
 ; TODO can we make a FB vector table and emulation routines for the Cx16s' GRAPH_init() call? to replace the builtin 320x200 fb driver?
 
 gfx2 {
@@ -36,7 +37,7 @@ gfx2 {
     sub screen_mode(ubyte mode) {
         when mode {
             1 -> {
-                ; lores monchrome
+                ; lores monochrome
                 cx16.VERA_DC_VIDEO = (cx16.VERA_DC_VIDEO & %11001111) | %00100000      ; enable only layer 1
                 cx16.VERA_DC_HSCALE = 64
                 cx16.VERA_DC_VSCALE = 64
@@ -274,9 +275,9 @@ _done
                         ora  colorbits,y
                         sta  cx16.VERA_DATA0
                         cpy  #%00000011         ; next vera byte?
-                        bne  +
+                        bne  ++
                         inc  cx16.VERA_ADDR_L
-                        bne  +
+                        bne  ++
                         inc  cx16.VERA_ADDR_M
 +                       bne  +
                         inc  cx16.VERA_ADDR_H
@@ -292,92 +293,56 @@ _done
     }
 
     sub vertical_line(uword x, uword y, uword height, ubyte color) {
-        position(x,y)
         when active_mode {
             1, 5 -> {
-                ; monochrome, either resolution
-                ; note for the 1 bpp modes we can't use vera's auto increment mode because we have to 'or' the pixel data in place.
-                ; TODO use TWO vera adress pointers simultaneously one for reading, one for writing, so auto-increment IS possible
-                cx16.VERA_ADDR_H &= %00000111   ; no auto advance
-                cx16.r15 = gfx2.plot.bits[x as ubyte & 7]           ; bitmask
-                if active_mode>=5
-                    cx16.r14 = 640/8
-                else
-                    cx16.r14 = 320/8
+                ; monochrome, lo-res
+                cx16.r15L = gfx2.plot.bits[x as ubyte & 7]           ; bitmask
                 if color {
                     if monochrome_dont_stipple_flag {
+                        ; draw continuous line.
+                        position2(x,y,true)
+                        if active_mode==1
+                            set_both_strides(11)    ; 40 increment = 1 line in 320 px monochrome
+                        else
+                            set_both_strides(12)    ; 80 increment = 1 line in 640 px monochrome
                         repeat height {
                             %asm {{
                                 lda  cx16.VERA_DATA0
-                                ora  cx16.r15
-                                sta  cx16.VERA_DATA0
-                                lda  cx16.VERA_ADDR_L
-                                clc
-                                adc  cx16.r14                 ; advance vera ptr to go to the next line
-                                sta  cx16.VERA_ADDR_L
-                                lda  cx16.VERA_ADDR_M
-                                adc  #0
-                                sta  cx16.VERA_ADDR_M
-                                ; lda  cx16.VERA_ADDR_H     ; the bitmap size is small enough to not have to deal with the _H part.
-                                ; adc  #0
-                                ; sta  cx16.VERA_ADDR_H
+                                ora  cx16.r15L
+                                sta  cx16.VERA_DATA1
                             }}
                         }
                     } else {
-                        ; stippling.
-                        height = (height+1)/2       ; TODO is the line sometimes 1 pixel too long now because of rounding?
-                        %asm {{
-                            lda x
-                            eor y
-                            and #1
-                            bne +
-                            lda  cx16.VERA_ADDR_L
-                            clc
-                            adc  cx16.r14                ; advance vera ptr to go to the next line for correct stipple pattern
-                            sta  cx16.VERA_ADDR_L
-                            lda  cx16.VERA_ADDR_M
-                            adc  #0
-                            sta  cx16.VERA_ADDR_M
-        +
-                            asl  cx16.r14
-                            ldy  height
-                            beq  +
-        -                   lda  cx16.VERA_DATA0
-                            ora  cx16.r15
-                            sta  cx16.VERA_DATA0
-                            lda  cx16.VERA_ADDR_L
-                            clc
-                            adc  cx16.r14               ; advance vera data ptr to go to the next-next line
-                            sta  cx16.VERA_ADDR_L
-                            lda  cx16.VERA_ADDR_M
-                            adc  #0
-                            sta  cx16.VERA_ADDR_M
-                            ; lda  cx16.VERA_ADDR_H      ; the bitmap size is small enough to not have to deal with the _H part.
-                            ; adc  #0
-                            ; sta  cx16.VERA_ADDR_H
-                            dey
-                            bne  -
-        +
-                        }}
+                        ; draw stippled line.
+                        if x&1 {
+                            y++
+                            height--
+                        }
+                        position2(x,y,true)
+                        if active_mode==1
+                            set_both_strides(12)    ; 80 increment = 2 line in 320 px monochrome
+                        else
+                            set_both_strides(13)    ; 160 increment = 2 line in 640 px monochrome
+                        repeat height/2 {
+                            %asm {{
+                                lda  cx16.VERA_DATA0
+                                ora  cx16.r15L
+                                sta  cx16.VERA_DATA1
+                            }}
+                        }
                     }
                 } else {
-                    cx16.r15 = ~cx16.r15
+                    position2(x,y,true)
+                    cx16.r15 = ~cx16.r15    ; erase pixels
+                    if active_mode==1
+                        set_both_strides(11)    ; 40 increment = 1 line in 320 px monochrome
+                    else
+                        set_both_strides(12)    ; 80 increment = 1 line in 640 px monochrome
                     repeat height {
                         %asm {{
                             lda  cx16.VERA_DATA0
-                            and  cx16.r15
-                            sta  cx16.VERA_DATA0
-                            lda  cx16.VERA_ADDR_L
-                            clc
-                            adc  cx16.r14             ; advance vera data ptr to go to the next line
-                            sta  cx16.VERA_ADDR_L
-                            lda  cx16.VERA_ADDR_M
-                            adc  #0
-                            sta  cx16.VERA_ADDR_M
-                            ; the bitmap size is small enough to not have to deal with the _H part:
-                            ; lda  cx16.VERA_ADDR_H
-                            ; adc  #0
-                            ; sta  cx16.VERA_ADDR_H
+                            and  cx16.r15L
+                            sta  cx16.VERA_DATA1
                         }}
                     }
                 }
@@ -385,6 +350,7 @@ _done
             4 -> {
                 ; lores 256c
                 ; set vera auto-increment to 320 pixel increment (=next line)
+                position(x,y)
                 cx16.VERA_ADDR_H = cx16.VERA_ADDR_H & %00000111 | (14<<4)
                 %asm {{
                     ldy  height
@@ -398,83 +364,78 @@ _done
             }
             6 -> {
                 ; highres 4c
-                ; note for this mode we can't use vera's auto increment mode because we have to 'or' the pixel data in place.
-                ; TODO use TWO vera adress pointers simultaneously one for reading, one for writing, so auto-increment IS possible
-                cx16.VERA_ADDR_H &= %00000111   ; no auto advance
-                ; TODO also mostly usable for lores 4c?
-                void addr_mul_24_for_highres_4c(y, x)      ; 24 bits result is in r0 and r1L (highest byte)
-
-                ; TODO optimize the loop in pure assembly
+                ; use TWO vera adress pointers simultaneously one for reading, one for writing, so auto-increment is possible
+                if height==0
+                    return
+                position2(x,y,true)
+                set_both_strides(13)    ; 160 increment = 1 line in 640 px 4c mode
                 color &= 3
                 color <<= gfx2.plot.shift4c[lsb(x) & 3]
                 ubyte mask = gfx2.plot.mask4c[lsb(x) & 3]
                 repeat height {
-                    ubyte value = cx16.vpeek(lsb(cx16.r1), cx16.r0) & mask | color
-                    cx16.vpoke(lsb(cx16.r1), cx16.r0, value)
                     %asm {{
-                        ; 24 bits add 160 (640/4)
-                        clc
-                        lda  cx16.r0
-                        adc  #640/4
-                        sta  cx16.r0
-                        lda  cx16.r0+1
-                        adc  #0
-                        sta  cx16.r0+1
-                        bcc  +
-                        inc  cx16.r1
-+
+                        lda  cx16.VERA_DATA0
+                        and  mask
+                        ora  color
+                        sta  cx16.VERA_DATA1
                     }}
                 }
             }
         }
 
+        sub set_both_strides(ubyte stride) {
+            stride <<= 4
+            cx16.VERA_CTRL = 0
+            cx16.VERA_ADDR_H = cx16.VERA_ADDR_H & %00000111 | stride
+            cx16.VERA_CTRL = 1
+            cx16.VERA_ADDR_H = cx16.VERA_ADDR_H & %00000111 | stride
+        }
+
     }
 
     sub line(uword @zp x1, uword @zp y1, uword @zp x2, uword @zp y2, ubyte color) {
         ; Bresenham algorithm.
         ; This code special-cases various quadrant loops to allow simple ++ and -- operations.
-        ; TODO there are some slight errors at the first/last pixels in certain slopes...
         if y1>y2 {
             ; make sure dy is always positive to have only 4 instead of 8 special cases
             swap(x1, x2)
             swap(y1, y2)
         }
-        word @zp dx = x2-x1 as word
-        word @zp dy = y2-y1 as word
+        word @zp dx = (x2 as word)-x1
+        word @zp dy = (y2 as word)-y1
 
         if dx==0 {
-            vertical_line(x1, y1, abs(dy)+1 as uword, color)
+            vertical_line(x1, y1, abs(dy) as uword +1, color)
             return
         }
         if dy==0 {
             if x1>x2
                 x1=x2
-            horizontal_line(x1, y1, abs(dx)+1 as uword, color)
+            horizontal_line(x1, y1, abs(dx) as uword +1, color)
             return
         }
 
-        ; TODO rewrite the rest in optimized assembly (or reuse GRAPH_draw_line if we can get the FB replacement vector layer working)
         word @zp d = 0
-        ubyte positive_ix = true
+        cx16.r13 = true      ; 'positive_ix'
         if dx < 0 {
             dx = -dx
-            positive_ix = false
+            cx16.r13 = false
         }
-        dx *= 2
-        dy *= 2
+        word @zp dx2 = dx*2
+        word @zp dy2 = dy*2
         cx16.r14 = x1       ; internal plot X
 
         if dx >= dy {
-            if positive_ix {
+            if cx16.r13 {
                 repeat {
                     plot(cx16.r14, y1, color)
                     if cx16.r14==x2
                         return
                     cx16.r14++
-                    d += dy
+                    d += dy2
                     if d > dx {
                         y1++
-                        d -= dx
+                        d -= dx2
                     }
                 }
             } else {
@@ -483,25 +444,25 @@ _done
                     if cx16.r14==x2
                         return
                     cx16.r14--
-                    d += dy
+                    d += dy2
                     if d > dx {
                         y1++
-                        d -= dx
+                        d -= dx2
                     }
                 }
             }
         }
         else {
-            if positive_ix {
+            if cx16.r13 {
                 repeat {
                     plot(cx16.r14, y1, color)
                     if y1 == y2
                         return
                     y1++
-                    d += dx
+                    d += dx2
                     if d > dy {
                         cx16.r14++
-                        d -= dy
+                        d -= dy2
                     }
                 }
             } else {
@@ -510,10 +471,10 @@ _done
                     if y1 == y2
                         return
                     y1++
-                    d += dx
+                    d += dx2
                     if d > dy {
                         cx16.r14--
-                        d -= dy
+                        d -= dy2
                     }
                 }
             }
@@ -589,8 +550,6 @@ _done
         ubyte[8] bits = [128, 64, 32, 16, 8, 4, 2, 1]
         ubyte[4] mask4c = [%00111111, %11001111, %11110011, %11111100]
         ubyte[4] shift4c = [6,4,2,0]
-        uword addr
-        ubyte value
 
         when active_mode {
             1 -> {
@@ -602,23 +561,43 @@ _done
                     and  #1
                 }}
                 if_nz {
-                    addr = x/8 + y*(320/8)
-                    value = bits[lsb(x)&7]
-                    if color
-                        cx16.vpoke_or(0, addr, value)
-                    else {
-                        value = ~value
-                        cx16.vpoke_and(0, addr, value)
-                    }
+                    cx16.r0L = lsb(x) & 7       ; xbits
+                    x /= 8
+                    x += y*(320/8)
+                    %asm {{
+                        stz  cx16.VERA_CTRL
+                        stz  cx16.VERA_ADDR_H
+                        lda  x+1
+                        sta  cx16.VERA_ADDR_M
+                        lda  x
+                        sta  cx16.VERA_ADDR_L
+                        ldy  cx16.r0L       ; xbits
+                        lda  bits,y
+                        ldy  color
+                        beq  +
+                        tsb  cx16.VERA_DATA0
+                        bra  ++
++                       trb  cx16.VERA_DATA0
++
+                    }}
                 }
             }
+            ; TODO mode 2,3
             4 -> {
                 ; lores 256c
                 void addr_mul_24_for_lores_256c(y, x)      ; 24 bits result is in r0 and r1L (highest byte)
-                cx16.vpoke(lsb(cx16.r1), cx16.r0, color)
-                ; activate vera auto-increment mode so next_pixel() can be used after this
-                cx16.VERA_ADDR_H = cx16.VERA_ADDR_H & %00000111 | %00010000
-                color = cx16.VERA_DATA0
+                %asm {{
+                    stz  cx16.VERA_CTRL
+                    lda  cx16.r1
+                    ora  #%00010000     ; enable auto-increment so next_pixel() can be used after this
+                    sta  cx16.VERA_ADDR_H
+                    lda  cx16.r0+1
+                    sta  cx16.VERA_ADDR_M
+                    lda  cx16.r0
+                    sta  cx16.VERA_ADDR_L
+                    lda  color
+                    sta  cx16.VERA_DATA0
+                }}
             }
             5 -> {
                 ; highres monochrome
@@ -629,26 +608,48 @@ _done
                     and  #1
                 }}
                 if_nz {
-                    addr = x/8 + y*(640/8)
-                    value = bits[lsb(x)&7]
-                    if color
-                        cx16.vpoke_or(0, addr, value)
-                    else {
-                        value = ~value
-                        cx16.vpoke_and(0, addr, value)
-                    }
+                    cx16.r0L = lsb(x) & 7       ; xbits
+                    x /= 8
+                    x += y*(640/8)
+                    %asm {{
+                        stz  cx16.VERA_CTRL
+                        stz  cx16.VERA_ADDR_H
+                        lda  x+1
+                        sta  cx16.VERA_ADDR_M
+                        lda  x
+                        sta  cx16.VERA_ADDR_L
+                        ldy  cx16.r0L           ; xbits
+                        lda  bits,y
+                        ldy  color
+                        beq  +
+                        tsb  cx16.VERA_DATA0
+                        bra  ++
++                       trb  cx16.VERA_DATA0
++
+                    }}
                 }
             }
             6 -> {
                 ; highres 4c
                 ; TODO also mostly usable for lores 4c?
                 void addr_mul_24_for_highres_4c(y, x)      ; 24 bits result is in r0 and r1L (highest byte)
+                cx16.r2L = lsb(x) & 3       ; xbits
                 color &= 3
-                color <<= shift4c[lsb(x) & 3]
-                ; TODO optimize the vera memory manipulation in pure assembly
-                cx16.VERA_ADDR_H &= %00000111   ; no auto advance
-                value = cx16.vpeek(lsb(cx16.r1), cx16.r0) & mask4c[lsb(x) & 3] | color
-                cx16.vpoke(lsb(cx16.r1), cx16.r0, value)
+                color <<= shift4c[cx16.r2L]
+                %asm {{
+                    stz  cx16.VERA_CTRL
+                    lda  cx16.r1L
+                    sta  cx16.VERA_ADDR_H
+                    lda  cx16.r0H
+                    sta  cx16.VERA_ADDR_M
+                    lda  cx16.r0L
+                    sta  cx16.VERA_ADDR_L
+                    ldy  cx16.r2L           ; xbits
+                    lda  mask4c,y
+                    and  cx16.VERA_DATA0
+                    ora  color
+                    sta  cx16.VERA_DATA0
+                }}
             }
         }
     }
@@ -682,6 +683,20 @@ _done
         }
     }
 
+    sub position2(uword @zp x, uword y, ubyte also_port_1) {
+        position(x, y)
+        if also_port_1 {
+            when active_mode {
+                1, 5 -> cx16.vaddr(0, cx16.r0, 1, 1)
+                ; TODO modes 2, 3
+                4, 6 -> {
+                    ubyte bank = lsb(cx16.r1)
+                    cx16.vaddr(bank, cx16.r0, 1, 1)
+                }
+            }
+        }
+    }
+
     inline asmsub next_pixel(ubyte color @A) {
         ; -- sets the next pixel byte to the graphics chip.
         ;    for 8 bpp screens this will plot 1 pixel.
@@ -761,13 +776,13 @@ _done
     sub text(uword @zp x, uword y, ubyte color, uword 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.
-        ;    NOTE: in monochrome (1bpp) screen modes, x position is currently constrained to mulitples of 8 !  TODO allow per-pixel horizontal positioning
+        ;    NOTE: in monochrome (1bpp) screen modes, x position is currently constrained to multiples of 8 !  TODO allow per-pixel horizontal positioning
         uword chardataptr
         when active_mode {
             1, 5 -> {
                 ; monochrome mode, either resolution
                 cx16.r2 = 40
-                if active_mode>=5
+                if active_mode==5
                     cx16.r2 = 80
                 while @(sctextptr) {
                     chardataptr = charset_addr + (@(sctextptr) as uword)*8

compiler/res/prog8lib/cx16/graphics.p8

@@ -4,7 +4,7 @@
 
 ; Bitmap pixel graphics module for the CommanderX16
 ; wraps the graphics functions that are in ROM.
-; only black/white monchrome 320x200 for now. (i.e. truncated at the bottom)
+; only black/white monochrome 320x200 for now. (i.e. truncated at the bottom)
 ; For full-screen 640x480 or 320x240 graphics, use the "gfx2" module instead. (but that is Cx16-specific)
 ; Note: there is no color palette manipulation here, you have to do that yourself or use the "palette" module.
 

compiler/res/prog8lib/cx16/palette.p8

@@ -70,6 +70,14 @@ palette {
         }
     }
 
+    inline sub set_all_black() {
+        set_monochrome($000, $000)
+    }
+
+    inline sub set_all_white() {
+        set_monochrome($fff, $fff)
+    }
+
     sub set_grayscale() {
         vera_palette_ptr = $fa00
         repeat 16 {

compiler/res/prog8lib/cx16/syslib.p8

@@ -24,7 +24,7 @@ romsub $FF8D = VECTOR(uword userptr @ XY, ubyte dir @ Pc) clobbers(A,Y)     ; re
 romsub $FF90 = SETMSG(ubyte value @ A)                          ; set Kernal message control flag
 romsub $FF93 = SECOND(ubyte address @ A) clobbers(A)            ; (alias: LSTNSA) send secondary address after LISTEN
 romsub $FF96 = TKSA(ubyte address @ A) clobbers(A)              ; (alias: TALKSA) send secondary address after TALK
-romsub $FF99 = MEMTOP(uword address @ XY, ubyte dir @ Pc) -> uword @ XY     ; read/set top of memory  pointer.   NOTE: as a Cx16 extension, also returns the number of RAM memory banks in register A !  See MEMTOP2
+romsub $FF99 = MEMTOP(uword address @ XY, ubyte dir @ Pc) -> uword @ XY     ; read/set top of memory  pointer.   NOTE: as a Cx16 extension, also returns the number of RAM memory banks in register A !  See cx16.numbanks()
 romsub $FF9C = MEMBOT(uword address @ XY, ubyte dir @ Pc) -> uword @ XY     ; read/set bottom of memory  pointer
 romsub $FF9F = SCNKEY() clobbers(A,X,Y)                         ; scan the keyboard
 romsub $FFA2 = SETTMO(ubyte timeout @ A)                        ; set time-out flag for IEEE bus
@@ -35,7 +35,7 @@ romsub $FFAE = UNLSN() clobbers(A)                              ; command serial
 romsub $FFB1 = LISTEN(ubyte device @ A) clobbers(A)             ; command serial bus device to LISTEN
 romsub $FFB4 = TALK(ubyte device @ A) clobbers(A)               ; command serial bus device to TALK
 romsub $FFB7 = READST() -> ubyte @ A                            ; read I/O status word
-romsub $FFBA = SETLFS(ubyte logical @ A, ubyte device @ X, ubyte address @ Y)   ; set logical file parameters
+romsub $FFBA = SETLFS(ubyte logical @ A, ubyte device @ X, ubyte secondary @ Y)   ; set logical file parameters
 romsub $FFBD = SETNAM(ubyte namelen @ A, str filename @ XY)     ; set filename parameters
 romsub $FFC0 = OPEN() clobbers(X,Y) -> ubyte @Pc, ubyte @A      ; (via 794 ($31A)) open a logical file
 romsub $FFC3 = CLOSE(ubyte logical @ A) clobbers(A,X,Y)         ; (via 796 ($31C)) close a logical file
@@ -44,10 +44,10 @@ romsub $FFC9 = CHKOUT(ubyte logical @ X) clobbers(A,X)          ; (via 800 ($320
 romsub $FFCC = CLRCHN() clobbers(A,X)                           ; (via 802 ($322)) restore default devices
 romsub $FFCF = CHRIN() clobbers(X, Y) -> ubyte @ A   ; (via 804 ($324)) input a character (for keyboard, read a whole line from the screen) A=byte read.
 romsub $FFD2 = CHROUT(ubyte char @ A)                           ; (via 806 ($326)) output a character
-romsub $FFD5 = LOAD(ubyte verify @ A, uword address @ XY) -> ubyte @Pc, ubyte @ A, ubyte @ X, ubyte @ Y     ; (via 816 ($330)) load from device
-romsub $FFD8 = SAVE(ubyte zp_startaddr @ A, uword endaddr @ XY) -> ubyte @ Pc, ubyte @ A                    ; (via 818 ($332)) save to a device
+romsub $FFD5 = LOAD(ubyte verify @ A, uword address @ XY) -> ubyte @Pc, ubyte @ A, uword @ XY     ; (via 816 ($330)) load from device
+romsub $FFD8 = SAVE(ubyte zp_startaddr @ A, uword endaddr @ XY) -> ubyte @ Pc, ubyte @ A          ; (via 818 ($332)) save to a device
 romsub $FFDB = SETTIM(ubyte low @ A, ubyte middle @ X, ubyte high @ Y)      ; set the software clock
-romsub $FFDE = RDTIM() -> ubyte @ A, ubyte @ X, ubyte @ Y       ; read the software clock
+romsub $FFDE = RDTIM() -> ubyte @ A, ubyte @ X, ubyte @ Y       ; read the software clock (A=lo,X=mid,Y=high)
 romsub $FFE1 = STOP() clobbers(X) -> ubyte @ Pz, ubyte @ A      ; (via 808 ($328)) check the STOP key (and some others in A)
 romsub $FFE4 = GETIN() clobbers(X,Y) -> ubyte @Pc, ubyte @ A    ; (via 810 ($32A)) get a character
 romsub $FFE7 = CLALL() clobbers(A,X)                            ; (via 812 ($32C)) close all files
@@ -74,7 +74,7 @@ asmsub STOP2() -> ubyte @A  {
 }
 
 asmsub RDTIM16() -> uword @AY {
-    ; --  like RDTIM() but only returning the lower 16 bits for convenience
+    ; --  like RDTIM() but only returning the lower 16 bits in AY for convenience
     %asm {{
         phx
         jsr  c64.RDTIM
@@ -87,17 +87,6 @@ asmsub RDTIM16() -> uword @AY {
     }}
 }
 
-asmsub MEMTOP2() -> ubyte @A {
-    ; -- uses MEMTOP's cx16 extension to query the number of available RAM banks.
-    %asm {{
-        phx
-        sec
-        jsr  c64.MEMTOP
-        plx
-        rts
-    }}
-}
-
 }
 
 cx16 {
@@ -127,6 +116,41 @@ cx16 {
     &uword r14 = $001e
     &uword r15 = $0020
 
+    &ubyte r0L  = $0002
+    &ubyte r1L  = $0004
+    &ubyte r2L  = $0006
+    &ubyte r3L  = $0008
+    &ubyte r4L  = $000a
+    &ubyte r5L  = $000c
+    &ubyte r6L  = $000e
+    &ubyte r7L  = $0010
+    &ubyte r8L  = $0012
+    &ubyte r9L  = $0014
+    &ubyte r10L = $0016
+    &ubyte r11L = $0018
+    &ubyte r12L = $001a
+    &ubyte r13L = $001c
+    &ubyte r14L = $001e
+    &ubyte r15L = $0020
+
+    &ubyte r0H  = $0003
+    &ubyte r1H  = $0005
+    &ubyte r2H  = $0007
+    &ubyte r3H  = $0009
+    &ubyte r4H  = $000b
+    &ubyte r5H  = $000d
+    &ubyte r6H  = $000f
+    &ubyte r7H  = $0011
+    &ubyte r8H  = $0013
+    &ubyte r9H  = $0015
+    &ubyte r10H = $0017
+    &ubyte r11H = $0019
+    &ubyte r12H = $001b
+    &ubyte r13H = $001d
+    &ubyte r14H = $001f
+    &ubyte r15H = $0021
+
+
 ; VERA registers
 
     const uword VERA_BASE       = $9F20
@@ -172,7 +196,7 @@ cx16 {
 
 ; I/O
 
-    const uword  via1   = $9f60                  ;VIA 6522 #1
+    const uword  via1   = $9f00                  ;VIA 6522 #1
     &ubyte  d1prb	= via1+0
     &ubyte  d1pra	= via1+1
     &ubyte  d1ddrb	= via1+2
@@ -190,7 +214,7 @@ cx16 {
     &ubyte  d1ier	= via1+14
     &ubyte  d1ora	= via1+15
 
-    const uword  via2   = $9f70                  ;VIA 6522 #2
+    const uword  via2   = $9f10                  ;VIA 6522 #2
     &ubyte  d2prb	= via2+0
     &ubyte  d2pra	= via2+1
     &ubyte  d2ddrb	= via2+2
@@ -208,6 +232,11 @@ cx16 {
     &ubyte  d2ier	= via2+14
     &ubyte  d2ora	= via2+15
 
+    &ubyte  ym2151adr	= $9f40
+    &ubyte  ym2151dat	= $9f41
+
+    const uword  extdev	= $9f60
+
 
 ; ---- Commander X-16 additions on top of C64 kernal routines ----
 ; spelling of the names is taken from the Commander X-16 rom sources
@@ -294,16 +323,25 @@ romsub $fecc = monitor()  clobbers(A,X,Y)
 inline asmsub rombank(ubyte rombank @A) {
     ; -- set the rom banks
     %asm {{
-        sta  $01            ; rom bank register (new)
-        sta  cx16.d1prb     ; rom bank register (old)
+        sta  $01            ; rom bank register (v39+, used to be cx16.d1prb $9f60 in v38)
     }}
 }
 
 inline asmsub rambank(ubyte rambank @A) {
     ; -- set the ram bank
     %asm {{
-        sta  $00            ; ram bank register (new)
-        sta  cx16.d1pra     ; ram bank register (old)
+        sta  $00            ; ram bank register (v39+, used to be cx16.d1pra $9f61 in v38)
+    }}
+}
+
+asmsub numbanks() -> ubyte @A {
+    ; -- uses MEMTOP's cx16 extension to query the number of available RAM banks. (each is 8 Kb)
+    %asm {{
+        phx
+        sec
+        jsr  c64.MEMTOP
+        plx
+        rts
     }}
 }
 
@@ -350,75 +388,126 @@ asmsub vaddr(ubyte bank @A, uword address @R0, ubyte addrsel @R1, byte autoIncrO
 }
 
 asmsub vpoke(ubyte bank @A, uword address @R0, ubyte value @Y) clobbers(A) {
-        ; -- write a single byte to VERA's video memory
-        ;    note: inefficient when writing multiple sequential bytes!
-        %asm {{
-            stz  cx16.VERA_CTRL
-            and  #1
-            sta  cx16.VERA_ADDR_H
-            lda  cx16.r0
-            sta  cx16.VERA_ADDR_L
-            lda  cx16.r0+1
-            sta  cx16.VERA_ADDR_M
-            sty  cx16.VERA_DATA0
-            rts
-        }}
+    ; -- write a single byte to VERA's video memory
+    ;    note: inefficient when writing multiple sequential bytes!
+    %asm {{
+        stz  cx16.VERA_CTRL
+        and  #1
+        sta  cx16.VERA_ADDR_H
+        lda  cx16.r0
+        sta  cx16.VERA_ADDR_L
+        lda  cx16.r0+1
+        sta  cx16.VERA_ADDR_M
+        sty  cx16.VERA_DATA0
+        rts
+    }}
 }
 
 asmsub vpoke_or(ubyte bank @A, uword address @R0, ubyte value @Y) clobbers (A) {
-        ; -- or a single byte to the value already in the VERA's video memory at that location
-        ;    note: inefficient when writing multiple sequential bytes!
-        %asm {{
-            stz  cx16.VERA_CTRL
-            and  #1
-            sta  cx16.VERA_ADDR_H
-            lda  cx16.r0
-            sta  cx16.VERA_ADDR_L
-            lda  cx16.r0+1
-            sta  cx16.VERA_ADDR_M
-            tya
-            ora  cx16.VERA_DATA0
-            sta  cx16.VERA_DATA0
-            rts
-        }}
+    ; -- or a single byte to the value already in the VERA's video memory at that location
+    ;    note: inefficient when writing multiple sequential bytes!
+    %asm {{
+        stz  cx16.VERA_CTRL
+        and  #1
+        sta  cx16.VERA_ADDR_H
+        lda  cx16.r0
+        sta  cx16.VERA_ADDR_L
+        lda  cx16.r0+1
+        sta  cx16.VERA_ADDR_M
+        tya
+        ora  cx16.VERA_DATA0
+        sta  cx16.VERA_DATA0
+        rts
+    }}
 }
 
 asmsub vpoke_and(ubyte bank @A, uword address @R0, ubyte value @Y) clobbers(A) {
-        ; -- and a single byte to the value already in the VERA's video memory at that location
-        ;    note: inefficient when writing multiple sequential bytes!
-        %asm {{
-            stz  cx16.VERA_CTRL
-            and  #1
-            sta  cx16.VERA_ADDR_H
-            lda  cx16.r0
-            sta  cx16.VERA_ADDR_L
-            lda  cx16.r0+1
-            sta  cx16.VERA_ADDR_M
-            tya
-            and  cx16.VERA_DATA0
-            sta  cx16.VERA_DATA0
-            rts
-        }}
+    ; -- and a single byte to the value already in the VERA's video memory at that location
+    ;    note: inefficient when writing multiple sequential bytes!
+    %asm {{
+        stz  cx16.VERA_CTRL
+        and  #1
+        sta  cx16.VERA_ADDR_H
+        lda  cx16.r0
+        sta  cx16.VERA_ADDR_L
+        lda  cx16.r0+1
+        sta  cx16.VERA_ADDR_M
+        tya
+        and  cx16.VERA_DATA0
+        sta  cx16.VERA_DATA0
+        rts
+    }}
 }
 
 asmsub vpoke_xor(ubyte bank @A, uword address @R0, ubyte value @Y) clobbers (A) {
-        ; -- xor a single byte to the value already in the VERA's video memory at that location
-        ;    note: inefficient when writing multiple sequential bytes!
-        %asm {{
-            stz  cx16.VERA_CTRL
-            and  #1
-            sta  cx16.VERA_ADDR_H
-            lda  cx16.r0
-            sta  cx16.VERA_ADDR_L
-            lda  cx16.r0+1
-            sta  cx16.VERA_ADDR_M
-            tya
-            eor  cx16.VERA_DATA0
-            sta  cx16.VERA_DATA0
-            rts
-        }}
+    ; -- xor a single byte to the value already in the VERA's video memory at that location
+    ;    note: inefficient when writing multiple sequential bytes!
+    %asm {{
+        stz  cx16.VERA_CTRL
+        and  #1
+        sta  cx16.VERA_ADDR_H
+        lda  cx16.r0
+        sta  cx16.VERA_ADDR_L
+        lda  cx16.r0+1
+        sta  cx16.VERA_ADDR_M
+        tya
+        eor  cx16.VERA_DATA0
+        sta  cx16.VERA_DATA0
+        rts
+    }}
 }
 
+asmsub vload(str name @R0, ubyte device @Y, ubyte bank @A, uword address @R1) -> ubyte @A {
+    ; -- like the basic command VLOAD "filename",device,bank,address
+    ;    loads a file into video memory in the given bank:address, returns success in A
+    ;    !! NOTE !! the V38 ROMs contain a bug in the LOAD code that makes the load address not work correctly,
+    ;               it works fine when loading from local filesystem
+    %asm {{
+        ; -- load a file into video ram
+        phx
+        pha
+        tya
+        tax
+        lda  #1
+        ldy  #0
+        jsr  c64.SETLFS
+        lda  cx16.r0
+        ldy  cx16.r0+1
+        jsr  prog8_lib.strlen
+        tya
+        ldx  cx16.r0
+        ldy  cx16.r0+1
+        jsr  c64.SETNAM
+        pla
+        clc
+        adc  #2
+        ldx  cx16.r1
+        ldy  cx16.r1+1
+        stz  P8ZP_SCRATCH_B1
+        jsr  c64.LOAD
+        bcs  +
+        inc  P8ZP_SCRATCH_B1
++       jsr  c64.CLRCHN
+        lda  #1
+        jsr  c64.CLOSE
+        plx
+        lda  P8ZP_SCRATCH_B1
+        rts
+    }}
+}
+
+inline asmsub joystick_get2(ubyte joynr @A) clobbers(Y) -> uword @AX  {
+    ; convenience routine to get the joystick state without requiring inline assembly that deals with the multiple return values.
+    ; Also disables interrupts to avoid the IRQ race condition mentioned here: https://github.com/commanderx16/x16-rom/issues/203
+    ; TODO once that issue is resolved, this routine can be redefined as:  romsub $ff56 = joystick_get2(ubyte joynr @A) clobbers(Y) -> uword @AX
+    %asm {{
+        sei
+        jsr  cx16.joystick_get
+        cli
+    }}
+}
+
+
 sub FB_set_pixels_from_buf(uword buffer, uword count) {
     %asm {{
             ; -- This is replacement code for the normal FB_set_pixels subroutine in ROM
@@ -460,11 +549,9 @@ asmsub  init_system()  {
     %asm {{
         sei
         cld
-        ;stz  $00
-        ;stz  $01
-        ;stz  d1prb      ; select rom bank 0 (enable kernal)
         lda  #$80
         sta  VERA_CTRL
+        stz  $01        ; select rom bank 0 (enable kernal)
         jsr  c64.IOINIT
         jsr  c64.RESTOR
         jsr  c64.CINT
@@ -664,23 +751,37 @@ sys {
 
 
     asmsub reset_system() {
-        ; Soft-reset the system back to Basic prompt.
+        ; Soft-reset the system back to initial power-on Basic prompt.
         %asm {{
             sei
-            stz  $01            ; bank the kernal in (new rom bank register)
-            stz  cx16.d1prb     ; bank the kernal in (old rom bank register)
+            stz  $01            ; bank the kernal in
             jmp  (cx16.RESET_VEC)
         }}
     }
 
-    sub wait(uword jiffies) {
-        ; --- wait approximately the given number of jiffies (1/60th seconds)
-        repeat jiffies {
-            ubyte jiff = lsb(c64.RDTIM16())
-            while jiff==lsb(c64.RDTIM16()) {
-                ; wait until 1 jiffy has passed
-            }
-        }
+    asmsub wait(uword jiffies @AY) {
+        ; --- wait approximately the given number of jiffies (1/60th seconds) (N or N+1)
+        ;     note: regular system vsync irq handler must be running, and no nother irqs
+        %asm {{
+-           wai             ; wait for irq (assume it was vsync)
+            cmp  #0
+            bne  +
+            dey
++           dec  a
+            bne  -
+            cpy  #0
+            bne  -
+            rts
+        }}
+    }
+
+    inline asmsub waitvsync()  {
+        ; --- suspend execution until the next vsync has occurred, without depending on custom irq handling.
+        ;     note: system vsync irq handler has to be active for this routine to work (and no other irqs).
+        ;     note: a more accurate way to wait for vsync is to set up a vsync irq handler instead.
+        %asm {{
+            wai
+        }}
     }
 
     inline asmsub memcopy(uword source @R0, uword target @R1, uword count @AY) clobbers(A,X,Y) {

compiler/res/prog8lib/cx16/textio.p8

@@ -420,7 +420,7 @@ _print_byte_digits
 		jsr  c64.CHROUT
 		pla
 		jsr  c64.CHROUT
-		jmp  _ones
+		bra  _ones
 +       pla
         cmp  #'0'
         beq  _ones
@@ -443,7 +443,7 @@ asmsub  print_b  (byte value @ A) clobbers(A,Y)  {
 		jsr  c64.CHROUT
 +		pla
 		jsr  conv.byte2decimal
-		jmp  print_ub._print_byte_digits
+		bra  print_ub._print_byte_digits
 	}}
 }
 
@@ -494,7 +494,7 @@ asmsub  print_uwbin  (uword value @ AY, ubyte prefix @ Pc) clobbers(A,Y)  {
 		jsr  print_ubbin
 		pla
 		clc
-		jmp  print_ubbin
+		bra  print_ubbin
 	}}
 }
 
@@ -507,7 +507,7 @@ asmsub  print_uwhex  (uword value @ AY, ubyte prefix @ Pc) clobbers(A,Y)  {
 		jsr  print_ubhex
 		pla
 		clc
-		jmp  print_ubhex
+		bra  print_ubhex
 	}}
 }
 
@@ -570,7 +570,7 @@ asmsub  print_w  (word value @ AY) clobbers(A,Y)  {
 		adc  #1
 		bcc  +
 		iny
-+		jmp  print_uw
++		bra  print_uw
 	}}
 }
 

compiler/res/prog8lib/diskio.p8

@@ -336,6 +336,45 @@ _end        rts
     }
 
 
+    ; ----- iterative file saver functions (uses io channel 14) -----
+
+    sub f_open_w(ubyte drivenumber, uword filenameptr) -> ubyte {
+        ; -- open a file for iterative writing with f_write
+        f_close_w()
+
+        c64.SETNAM(string.length(filenameptr), filenameptr)
+        c64.SETLFS(14, drivenumber, 1)
+        void c64.OPEN()          ; open 14,8,1,"filename"
+        if_cc {
+            void c64.CHKOUT(14)        ; use #14 as input channel
+            return not c64.READST()
+        }
+        f_close_w()
+        return false
+    }
+
+    sub f_write(uword bufferpointer, uword num_bytes) -> ubyte {
+        ; -- write the given umber of bytes to the currently open file
+        if num_bytes!=0 {
+            void c64.CHKOUT(14)        ; use #14 as input channel again
+            repeat num_bytes {
+                c64.CHROUT(@(bufferpointer))
+                bufferpointer++
+            }
+            return not c64.READST()
+        }
+        return true
+    }
+
+    sub f_close_w() {
+        ; -- end an iterative file writing session (close channels).
+        c64.CLRCHN()
+        c64.CLOSE(14)
+    }
+
+
+    ; ---- other functions ----
+
     sub status(ubyte drivenumber) -> uword {
         ; -- retrieve the disk drive's current status message
         uword messageptr = &filename
@@ -353,18 +392,22 @@ _end        rts
             messageptr++
         }
 
-io_error:
         @(messageptr) = 0
+done:
         c64.CLRCHN()        ; restore default i/o devices
         c64.CLOSE(15)
         return filename
-    }
 
+io_error:
+        filename = "?disk error"
+        goto done
+    }
 
     sub save(ubyte drivenumber, uword filenameptr, uword address, uword size) -> ubyte {
         c64.SETNAM(string.length(filenameptr), filenameptr)
         c64.SETLFS(1, drivenumber, 0)
         uword end_address = address + size
+        first_byte = 0      ; result var reuse
 
         %asm {{
             lda  address
@@ -381,7 +424,6 @@ io_error:
             plp
         }}
 
-        first_byte = 0      ; result var reuse
         if_cc
             first_byte = c64.READST()==0
 

compiler/res/prog8lib/math.asm

@@ -244,68 +244,45 @@ randseed	.proc
 		.pend
 
 
-randbyte	.proc
-	; -- 8-bit pseudo random number generator into A
-		lda  _seed
-		beq  _eor
-		asl  a
-		beq  _done	; if the input was $80, skip the EOR
-		bcc  _done
-_eor		eor  #$1d	; xor with magic value see below for possible values
-_done		sta  _seed
-		rts
-
-_seed		.byte  $3a
-
-		; possible 'magic' eor bytes are:
-		; $1d, $2b, $2d, $4d, $5f, $63, $65, $69
-		; $71, $87, $8d, $a9, $c3, $cf, $e7, $f5
-
+randbyte        .proc
+	; -- 8 bit pseudo random number generator into A (by just reusing randword)
+		jmp  randword
 		.pend
 
-
 randword	.proc
 	; -- 16 bit pseudo random number generator into AY
 
-magic_eor = $3f1d
-		; possible magic eor words are:
-		; $3f1d, $3f81, $3fa5, $3fc5, $4075, $409d, $40cd, $4109
- 		; $413f, $414b, $4153, $4159, $4193, $4199, $41af, $41bb
+		; rand64k       ;Factors of 65535: 3 5 17 257
+		lda sr1+1
+		asl a
+		asl a
+		eor sr1+1
+		asl a
+		eor sr1+1
+		asl a
+		asl a
+		eor sr1+1
+		asl a
+		rol sr1         ;shift this left, "random" bit comes from low
+		rol sr1+1
+		; rand32k       ;Factors of 32767: 7 31 151 are independent and can be combined
+		lda sr2+1
+		asl a
+		eor sr2+1
+		asl a
+		asl a
+		ror sr2         ;shift this right, random bit comes from high - nicer when eor with sr1
+		rol sr2+1
+		lda sr1+1         ;can be left out
+		eor sr2+1         ;if you dont use
+		tay               ;y as suggested
+		lda sr1           ;mix up lowbytes of SR1
+		eor sr2           ;and SR2 to combine both
+		rts
 
-		lda  _seed
-		beq  _lowZero	; $0000 and $8000 are special values to test for
+sr1     	.word $a55a
+sr2     	.word $7653
 
- 		; Do a normal shift
-		asl  _seed
-		lda  _seed+1
-		rol  a
-		bcc  _noEor
-
-_doEor		; high byte is in A
-		eor  #>magic_eor
-  		sta  _seed+1
-  		lda  _seed
-  		eor  #<magic_eor
-  		sta  _seed
-  		ldy  _seed+1
-  		rts
-
-_lowZero	lda  _seed+1
-		beq  _doEor	; High byte is also zero, so apply the EOR
-				; For speed, you could store 'magic' into 'seed' directly
-				; instead of running the EORs
-
- 		; wasn't zero, check for $8000
-		asl  a
-		beq  _noEor	; if $00 is left after the shift, then it was $80
-		bcs  _doEor	; else, do the EOR based on the carry bit as usual
-
-_noEor		sta  _seed+1
-		tay
-		lda  _seed
- 		rts
-
-_seed		.word	$2c9e
 		.pend
 
 
@@ -797,6 +774,13 @@ stack_mul_word_320	.proc
 		rts
 		.pend
 
+stack_mul_word_640	.proc
+		; stackW = (stackLo * 2 * 320)    (stackHi doesn't matter)
+		asl  P8ESTACK_LO+1,x
+		jmp  stack_mul_word_320
+		.pend
+
+
 ; ----------- optimized multiplications (in-place A (byte) and ?? (word)) : ---------
 mul_byte_3	.proc
 		; A = A + A*2
@@ -1287,6 +1271,13 @@ mul_word_320	.proc
 		rts
 		.pend
 
+mul_word_640	.proc
+		; AY = (A * 2 * 320) (msb in Y doesn't matter)
+		asl  a
+		jmp  mul_word_320
+		.pend
+
+
 ; ----------- end optimized multiplications -----------
 
 
@@ -1537,3 +1528,71 @@ _negative	lsr  a
 		rts
 		.pend
 
+
+square          .proc
+; -- calculate square root of signed word in AY, result in AY
+; routine by Lee Davsion, source: http://6502.org/source/integers/square.htm
+; using this routine is about twice as fast as doing a regular multiplication.
+;
+; Calculates the 16 bit unsigned integer square of the signed 16 bit integer in
+; Numberl/Numberh.  The result is always in the range 0 to 65025 and is held in
+; Squarel/Squareh
+;
+; The maximum input range is only +/-255 and no checking is done to ensure that
+; this is so.
+;
+; This routine is useful if you are trying to draw circles as for any circle
+;
+; x^2+y^2=r^2 where x and y are the co-ordinates of any point on the circle and
+; r is the circle radius
+
+numberl = P8ZP_SCRATCH_W1       ; number to square low byte
+numberh = P8ZP_SCRATCH_W1+1     ; number to square high byte
+squarel = P8ZP_SCRATCH_W2       ; square low byte
+squareh = P8ZP_SCRATCH_W2+1     ; square high byte
+tempsq = P8ZP_SCRATCH_B1        ; temp byte for intermediate result
+
+	sta  numberl
+	sty  numberh
+	stx  P8ZP_SCRATCH_REG
+
+        lda     #$00        ; clear a
+        sta     squarel     ; clear square low byte
+                            ; (no need to clear the high byte, it gets shifted out)
+        lda	numberl     ; get number low byte
+	ldx	numberh     ; get number high  byte
+	bpl	_nonneg      ; if +ve don't negate it
+                            ; else do a two's complement
+	eor	#$ff        ; invert
+        sec	            ; +1
+	adc	#$00        ; and add it
+
+_nonneg:
+	sta	tempsq      ; save abs(number)
+	ldx	#$08        ; set bit count
+
+_nextr2bit:
+	asl	squarel     ; low byte *2
+	rol	squareh     ; high byte *2+carry from low
+	asl	a           ; shift number byte
+	bcc	_nosqadd     ; don't do add if c = 0
+	tay                 ; save a
+	clc                 ; clear carry for add
+	lda	tempsq      ; get number
+	adc	squarel     ; add number^2 low byte
+	sta	squarel     ; save number^2 low byte
+	lda	#$00        ; clear a
+	adc	squareh     ; add number^2 high byte
+	sta	squareh     ; save number^2 high byte
+	tya                 ; get a back
+
+_nosqadd:
+	dex                 ; decrement bit count
+	bne	_nextr2bit   ; go do next bit
+
+	lda  squarel
+	ldy  squareh
+	ldx  P8ZP_SCRATCH_REG
+	rts
+
+		.pend

compiler/res/prog8lib/math.p8

@@ -3,5 +3,5 @@
 ; Written by Irmen de Jong (irmen@razorvine.net) - license: GNU GPL 3.0
 
 math {
-	%asminclude "library:math.asm", ""
+	%asminclude "library:math.asm"
 }

compiler/res/prog8lib/prog8_funcs.asm

@@ -432,6 +432,7 @@ func_min_ub_stack	.proc
 func_min_b_into_A	.proc
 		; -- min(barray) -> A.  (array in P8ZP_SCRATCH_W1, num elements in A)
 		tay
+		dey
 		lda  #127
 		sta  P8ZP_SCRATCH_B1
 -		lda  (P8ZP_SCRATCH_W1),y
@@ -548,6 +549,7 @@ func_min_w_stack	.proc
 func_max_ub_into_A	.proc
 		; -- max(ubarray) -> A  (array in P8ZP_SCRATCH_W1, num elements in A)
 		tay
+		dey
 		lda  #0
 		sta  P8ZP_SCRATCH_B1
 -		lda  (P8ZP_SCRATCH_W1),y

compiler/res/prog8lib/prog8_lib.asm

@@ -1072,3 +1072,14 @@ sign_extend_AY_byte	.proc
 		rts
 		.pend
 
+strlen          .proc
+        ; -- returns the number of bytes in the string in AY, in Y.
+		sta  P8ZP_SCRATCH_W1
+		sty  P8ZP_SCRATCH_W1+1
+		ldy  #0
+-		lda  (P8ZP_SCRATCH_W1),y
+		beq  +
+		iny
+		bne  -
++		rts
+		.pend

compiler/res/prog8lib/prog8_lib.p8

@@ -3,8 +3,8 @@
 ; Written by Irmen de Jong (irmen@razorvine.net) - license: GNU GPL 3.0
 
 prog8_lib {
-	%asminclude "library:prog8_lib.asm", ""
-	%asminclude "library:prog8_funcs.asm", ""
+	%asminclude "library:prog8_lib.asm"
+	%asminclude "library:prog8_funcs.asm"
 
 	uword @zp retval_interm_uw      ; to store intermediary expression results for return values (hopefully allocated on ZP to reduce code size)
 	word @zp retval_interm_w        ; to store intermediary expression results for return values (hopefully allocated on ZP to reduce code size)

compiler/res/prog8lib/string.p8

@@ -178,7 +178,7 @@ _found		sty  P8ZP_SCRATCH_B1
 
     asmsub compare(uword string1 @R0, uword string2 @AY) clobbers(Y) -> byte @A {
         ; Compares two strings for sorting.
-        ; Returns -1 (255), 0 or 1 depeding on wether string1 sorts before, equal or after string2.
+        ; Returns -1 (255), 0 or 1 depending on wether string1 sorts before, equal or after string2.
         ; Note that you can also directly compare strings and string values with eachother using
         ; comparison operators ==, < etcetera (it will use strcmp for you under water automatically).
         %asm {{
@@ -190,8 +190,8 @@ _found		sty  P8ZP_SCRATCH_B1
         }}
     }
 
-    asmsub lower(uword st @AY) {
-        ; Lowercases the petscii string in-place.
+    asmsub lower(uword st @AY) -> ubyte @Y {
+        ; Lowercases the petscii string in-place. Returns length of the string.
         ; (for efficiency, non-letter characters > 128 will also not be left intact,
         ;  but regular text doesn't usually contain those characters anyway.)
         %asm {{
@@ -213,8 +213,8 @@ _done       rts
         }}
     }
 
-    asmsub upper(uword st @AY) {
-        ; Uppercases the petscii string in-place.
+    asmsub upper(uword st @AY) -> ubyte @Y {
+        ; Uppercases the petscii string in-place. Returns length of the string.
         %asm {{
             sta  P8ZP_SCRATCH_W1
             sty  P8ZP_SCRATCH_W1+1

compiler/res/version.txt

@@ -1 +1 @@
-6.2
+7.0-BETA2

compiler/src/prog8/CompilerMain.kt

@@ -1,15 +1,13 @@
 package prog8
 
-import kotlinx.cli.ArgParser
-import kotlinx.cli.ArgType
-import kotlinx.cli.default
-import kotlinx.cli.multiple
+import kotlinx.cli.*
 import prog8.ast.base.AstException
 import prog8.compiler.CompilationResult
 import prog8.compiler.compileProgram
 import prog8.compiler.target.C64Target
 import prog8.compiler.target.Cx16Target
 import prog8.parser.ParsingFailedError
+import java.io.File
 import java.nio.file.FileSystems
 import java.nio.file.Path
 import java.nio.file.StandardWatchEventKinds
@@ -42,6 +40,7 @@ private fun compileMain(args: Array<String>) {
     val watchMode by cli.option(ArgType.Boolean, fullName = "watch", description = "continuous compilation mode (watches for file changes), greatly increases compilation speed")
     val slowCodegenWarnings by cli.option(ArgType.Boolean, fullName = "slowwarn", description="show debug warnings about slow/problematic assembly code generation")
     val compilationTarget by cli.option(ArgType.String, fullName = "target", description = "target output of the compiler, currently '${C64Target.name}' and '${Cx16Target.name}' available").default(C64Target.name)
+    val libDirs by cli.option(ArgType.String, fullName="libdirs", description = "list of extra paths to search in for imported modules").multiple().delimiter(File.pathSeparator)
     val moduleFiles by cli.argument(ArgType.String, fullName = "modules", description = "main module file(s) to compile").multiple(999)
 
     try {
@@ -57,6 +56,16 @@ private fun compileMain(args: Array<String>) {
         exitProcess(1)
     }
 
+    val faultyOption = moduleFiles.firstOrNull { it.startsWith('-') }
+    if(faultyOption!=null) {
+        System.err.println("Unknown command line option given: $faultyOption")
+        exitProcess(1)
+    }
+
+    val libdirs = libDirs.toMutableList()
+    if(libdirs.firstOrNull()!=".")
+        libdirs.add(0, ".")
+
     if(watchMode==true) {
         val watchservice = FileSystems.getDefault().newWatchService()
         val allImportedFiles = mutableSetOf<Path>()
@@ -66,7 +75,7 @@ private fun compileMain(args: Array<String>) {
             val results = mutableListOf<CompilationResult>()
             for(filepathRaw in moduleFiles) {
                 val filepath = pathFrom(filepathRaw).normalize()
-                val compilationResult = compileProgram(filepath, dontOptimize!=true, dontWriteAssembly!=true, slowCodegenWarnings==true, compilationTarget, outputPath)
+                val compilationResult = compileProgram(filepath, dontOptimize!=true, dontWriteAssembly!=true, slowCodegenWarnings==true, compilationTarget, libdirs, outputPath)
                 results.add(compilationResult)
             }
 
@@ -103,7 +112,7 @@ private fun compileMain(args: Array<String>) {
             val filepath = pathFrom(filepathRaw).normalize()
             val compilationResult: CompilationResult
             try {
-                compilationResult = compileProgram(filepath, dontOptimize!=true, dontWriteAssembly!=true, slowCodegenWarnings==true, compilationTarget, outputPath)
+                compilationResult = compileProgram(filepath, dontOptimize!=true, dontWriteAssembly!=true, slowCodegenWarnings==true, compilationTarget, libdirs, outputPath)
                 if(!compilationResult.success)
                     exitProcess(1)
             } catch (x: ParsingFailedError) {

compiler/src/prog8/compiler/BeforeAsmGenerationAstChanger.kt

@@ -8,25 +8,26 @@ import prog8.ast.expressions.*
 import prog8.ast.statements.*
 import prog8.ast.walk.AstWalker
 import prog8.ast.walk.IAstModification
+import prog8.ast.walk.IAstVisitor
 import prog8.compiler.target.ICompilationTarget
 
 
 internal class BeforeAsmGenerationAstChanger(val program: Program, val errors: IErrorReporter, private val compTarget: ICompilationTarget) : AstWalker() {
 
-    private val noModifications = emptyList<IAstModification>()
-
     override fun after(decl: VarDecl, parent: Node): Iterable<IAstModification> {
         subroutineVariables.add(decl.name to decl)
         if (decl.value == null && !decl.autogeneratedDontRemove && decl.type == VarDeclType.VAR && decl.datatype in NumericDatatypes) {
-            // a numeric vardecl without an initial value is initialized with zero,
-            // unless there's already an assignment below, that initializes the value
+            // A numeric vardecl without an initial value is initialized with zero,
+            // unless there's already an assignment below, that initializes the value.
+            // This allows you to restart the program and have the same starting values of the variables
             if(decl.allowInitializeWithZero)
             {
                 val nextAssign = decl.definingScope().nextSibling(decl) as? Assignment
-                if (nextAssign != null && nextAssign.target.isSameAs(IdentifierReference(listOf(decl.name), Position.DUMMY)))
+                if (nextAssign != null && nextAssign.target isSameAs IdentifierReference(listOf(decl.name), Position.DUMMY))
                     decl.value = null
-                else
+                else {
                     decl.value = decl.zeroElementValue()
+                }
             }
         }
         return noModifications
@@ -67,30 +68,37 @@ internal class BeforeAsmGenerationAstChanger(val program: Program, val errors: I
     }
 
     private val subroutineVariables = mutableListOf<Pair<String, VarDecl>>()
+    private val addedIfConditionVars = mutableSetOf<Pair<Subroutine, String>>()
 
     override fun before(subroutine: Subroutine, parent: Node): Iterable<IAstModification> {
         subroutineVariables.clear()
+        addedIfConditionVars.clear()
         return noModifications
     }
 
     override fun after(scope: AnonymousScope, parent: Node): Iterable<IAstModification> {
-        val decls = scope.statements.filterIsInstance<VarDecl>()
+        val decls = scope.statements.filterIsInstance<VarDecl>().filter { it.type == VarDeclType.VAR }
         subroutineVariables.addAll(decls.map { it.name to it })
 
         val sub = scope.definingSubroutine()
         if (sub != null) {
-            // move vardecls of the scope into the upper scope. Make sure the position remains the same!
-            val numericVarsWithValue = decls.filter { it.value != null && it.datatype in NumericDatatypes }
-            val replaceVardecls =numericVarsWithValue.map {
-                val initValue = it.value!!  // assume here that value has always been set by now
-                it.value = null     // make sure no value init assignment for this vardecl will be created later (would be superfluous)
-                val target = AssignTarget(IdentifierReference(listOf(it.name), it.position), null, null, it.position)
-                val assign = Assignment(target, initValue, it.position)
-                initValue.parent = assign
-                IAstModification.ReplaceNode(it, assign, scope)
+            // move any remaining vardecls of the scope into the upper scope. Make sure the position remains the same!
+            val replacements = mutableListOf<IAstModification>()
+            val movements = mutableListOf<IAstModification.InsertFirst>()
+
+            for(decl in decls) {
+                if(decl.value!=null && decl.datatype in NumericDatatypes) {
+                    val target = AssignTarget(IdentifierReference(listOf(decl.name), decl.position), null, null, decl.position)
+                    val assign = Assignment(target, decl.value!!, decl.position)
+                    replacements.add(IAstModification.ReplaceNode(decl, assign, scope))
+                    decl.value = null
+                    decl.allowInitializeWithZero = false
+                } else {
+                    replacements.add(IAstModification.Remove(decl, scope))
+                }
+                movements.add(IAstModification.InsertFirst(decl, sub))
             }
-            val moveVardeclsUp = decls.map { IAstModification.InsertFirst(it, sub) }
-            return replaceVardecls + moveVardeclsUp
+            return replacements + movements
         }
         return noModifications
     }
@@ -138,7 +146,7 @@ internal class BeforeAsmGenerationAstChanger(val program: Program, val errors: I
         // see if we can remove superfluous typecasts (outside of expressions)
         // such as casting byte<->ubyte,  word<->uword
         // Also the special typecast of a reference type (str, array) to an UWORD will be changed into address-of.
-        val sourceDt = typecast.expression.inferType(program).typeOrElse(DataType.STRUCT)
+        val sourceDt = typecast.expression.inferType(program).typeOrElse(DataType.UNDEFINED)
         if (typecast.type in ByteDatatypes && sourceDt in ByteDatatypes
                 || typecast.type in WordDatatypes && sourceDt in WordDatatypes) {
             if(typecast.parent !is Expression) {
@@ -154,16 +162,6 @@ internal class BeforeAsmGenerationAstChanger(val program: Program, val errors: I
         // The only place for now where we can do this is for:
         //    asmsub register pair parameter.
 
-        if(typecast.type in WordDatatypes) {
-            val fcall = typecast.parent as? IFunctionCall
-            if (fcall != null) {
-                val sub = fcall.target.targetStatement(program) as? Subroutine
-                if (sub != null && sub.isAsmSubroutine) {
-                    return listOf(IAstModification.ReplaceNode(typecast, typecast.expression, parent))
-                }
-            }
-        }
-
         if(sourceDt in PassByReferenceDatatypes) {
             if(typecast.type==DataType.UWORD) {
                 if(typecast.expression is IdentifierReference) {
@@ -194,9 +192,55 @@ internal class BeforeAsmGenerationAstChanger(val program: Program, val errors: I
             val booleanExpr = BinaryExpression(ifStatement.condition, "!=", NumericLiteralValue.optimalInteger(0, ifStatement.condition.position), ifStatement.condition.position)
             return listOf(IAstModification.ReplaceNode(ifStatement.condition, booleanExpr, ifStatement))
         }
+
+        if((binExpr.operator=="==" || binExpr.operator=="!=") &&
+            (binExpr.left as? NumericLiteralValue)?.number==0 &&
+            (binExpr.right as? NumericLiteralValue)?.number!=0)
+            throw CompilerException("if 0==X should have been swapped to if X==0")
+
+        // split the conditional expression into separate variables if the operand(s) is not simple.
+        // DISABLED FOR NOW AS IT GENEREATES LARGER CODE IN THE SIMPLE CASES LIKE    IF X {...}  or  IF NOT X {...}
+//        val modifications = mutableListOf<IAstModification>()
+//        if(!binExpr.left.isSimple) {
+//            val sub = binExpr.definingSubroutine()!!
+//            val (variable, isNew, assignment) = addIfOperandVar(sub, "left", binExpr.left)
+//            if(isNew)
+//                modifications.add(IAstModification.InsertFirst(variable, sub))
+//            modifications.add(IAstModification.InsertBefore(ifStatement, assignment, parent as INameScope))
+//            modifications.add(IAstModification.ReplaceNode(binExpr.left, IdentifierReference(listOf(variable.name), binExpr.position), binExpr))
+//            addedIfConditionVars.add(Pair(sub, variable.name))
+//        }
+//        if(!binExpr.right.isSimple) {
+//            val sub = binExpr.definingSubroutine()!!
+//            val (variable, isNew, assignment) = addIfOperandVar(sub, "right", binExpr.right)
+//            if(isNew)
+//                modifications.add(IAstModification.InsertFirst(variable, sub))
+//            modifications.add(IAstModification.InsertBefore(ifStatement, assignment, parent as INameScope))
+//            modifications.add(IAstModification.ReplaceNode(binExpr.right, IdentifierReference(listOf(variable.name), binExpr.position), binExpr))
+//            addedIfConditionVars.add(Pair(sub, variable.name))
+//        }
+//        return modifications
         return noModifications
     }
 
+//    private fun addIfOperandVar(sub: Subroutine, side: String, operand: Expression): Triple<VarDecl, Boolean, Assignment> {
+//        val dt = operand.inferType(program).typeOrElse(DataType.UNDEFINED)
+//        val varname = "prog8_ifvar_${side}_${dt.name.toLowerCase()}"
+//        val tgt = AssignTarget(IdentifierReference(listOf(varname), operand.position), null, null, operand.position)
+//        val assign = Assignment(tgt, operand, operand.position)
+//        if(Pair(sub, varname) in addedIfConditionVars) {
+//            val vardecl = VarDecl(VarDeclType.VAR, dt, ZeropageWish.DONTCARE, null, varname, null, null, false, true, operand.position)
+//            return Triple(vardecl, false, assign)
+//        }
+//        val existing = sub.statements.firstOrNull { it is VarDecl && it.name == varname} as VarDecl?
+//        return if (existing == null) {
+//            val vardecl = VarDecl(VarDeclType.VAR, dt, ZeropageWish.DONTCARE, null, varname, null, null, false, true, operand.position)
+//            Triple(vardecl, true, assign)
+//        } else {
+//            Triple(existing, false, assign)
+//        }
+//    }
+
     override fun after(untilLoop: UntilLoop, parent: Node): Iterable<IAstModification> {
         val binExpr = untilLoop.condition as? BinaryExpression
         if(binExpr==null || binExpr.operator !in comparisonOperators) {
@@ -216,4 +260,95 @@ internal class BeforeAsmGenerationAstChanger(val program: Program, val errors: I
         }
         return noModifications
     }
+
+    override fun after(functionCallStatement: FunctionCallStatement, parent: Node): Iterable<IAstModification> {
+        if(functionCallStatement.target.nameInSource==listOf("cmp")) {
+            // if the datatype of the arguments of cmp() are different, cast the byte one to word.
+            val arg1 = functionCallStatement.args[0]
+            val arg2 = functionCallStatement.args[1]
+            val dt1 = arg1.inferType(program).typeOrElse(DataType.UNDEFINED)
+            val dt2 = arg2.inferType(program).typeOrElse(DataType.UNDEFINED)
+            if(dt1 in ByteDatatypes) {
+                if(dt2 in ByteDatatypes)
+                    return noModifications
+                val cast1 = TypecastExpression(arg1, if(dt1==DataType.UBYTE) DataType.UWORD else DataType.WORD, true, functionCallStatement.position)
+                return listOf(IAstModification.ReplaceNode(arg1, cast1, functionCallStatement))
+            } else {
+                if(dt2 in WordDatatypes)
+                    return noModifications
+                val cast2 = TypecastExpression(arg2, if(dt2==DataType.UBYTE) DataType.UWORD else DataType.WORD, true, functionCallStatement.position)
+                return listOf(IAstModification.ReplaceNode(arg2, cast2, functionCallStatement))
+            }
+        }
+        return noModifications
+    }
+
+    override fun after(arrayIndexedExpression: ArrayIndexedExpression, parent: Node): Iterable<IAstModification> {
+
+        val containingStatement = getContainingStatement(arrayIndexedExpression)
+        if(getComplexArrayIndexedExpressions(containingStatement).size > 1) {
+            errors.err("it's not possible to use more than one complex array indexing expression in a single statement; break it up via a temporary variable for instance", containingStatement.position)
+            return noModifications
+        }
+
+
+        val index = arrayIndexedExpression.indexer.indexExpr
+        if(index !is NumericLiteralValue && index !is IdentifierReference) {
+            // replace complex indexing expression with a temp variable to hold the computed index first
+            return getAutoIndexerVarFor(arrayIndexedExpression)
+        }
+
+        return noModifications
+    }
+
+    private fun getComplexArrayIndexedExpressions(stmt: Statement): List<ArrayIndexedExpression> {
+
+        class Searcher : IAstVisitor {
+            val complexArrayIndexedExpressions = mutableListOf<ArrayIndexedExpression>()
+            override fun visit(arrayIndexedExpression: ArrayIndexedExpression) {
+                val ix = arrayIndexedExpression.indexer.indexExpr
+                if(ix !is NumericLiteralValue && ix !is IdentifierReference)
+                    complexArrayIndexedExpressions.add(arrayIndexedExpression)
+            }
+
+            override fun visit(branchStatement: BranchStatement) {}
+
+            override fun visit(forLoop: ForLoop) {}
+
+            override fun visit(ifStatement: IfStatement) {
+                ifStatement.condition.accept(this)
+            }
+
+            override fun visit(untilLoop: UntilLoop) {
+                untilLoop.condition.accept(this)
+            }
+        }
+
+        val searcher = Searcher()
+        stmt.accept(searcher)
+        return searcher.complexArrayIndexedExpressions
+    }
+
+    private fun getContainingStatement(expression: Expression): Statement {
+        var node: Node = expression
+        while(node !is Statement)
+            node = node.parent
+
+        return node
+    }
+
+    private fun getAutoIndexerVarFor(expr: ArrayIndexedExpression): MutableList<IAstModification> {
+        val modifications = mutableListOf<IAstModification>()
+        val statement = expr.containingStatement()
+        val dt = expr.indexer.indexExpr.inferType(program)
+        val register = if(dt.istype(DataType.UBYTE) || dt.istype(DataType.BYTE)) "r9L" else "r9"
+        // replace the indexer with just the variable (simply use a cx16 virtual register r9, that we HOPE is not used for other things in the expression...)
+        // assign the indexing expression to the helper variable, but only if that hasn't been done already
+        val target = AssignTarget(IdentifierReference(listOf("cx16", register), expr.indexer.position), null, null, expr.indexer.position)
+        val assign = Assignment(target, expr.indexer.indexExpr, expr.indexer.position)
+        modifications.add(IAstModification.InsertBefore(statement, assign, statement.definingScope()))
+        modifications.add(IAstModification.ReplaceNode(expr.indexer.indexExpr, target.identifier!!.copy(), expr.indexer))
+        return modifications
+    }
+
 }

compiler/src/prog8/compiler/Compiler.kt

@@ -70,6 +70,7 @@ fun compileProgram(filepath: Path,
                    writeAssembly: Boolean,
                    slowCodegenWarnings: Boolean,
                    compilationTarget: String,
+                   libdirs: List<String>,
                    outputDir: Path): CompilationResult {
     var programName = ""
     lateinit var programAst: Program
@@ -89,14 +90,14 @@ fun compileProgram(filepath: Path,
     try {
         val totalTime = measureTimeMillis {
             // import main module and everything it needs
-            val (ast, compilationOptions, imported) = parseImports(filepath, errors, compTarget)
+            val (ast, compilationOptions, imported) = parseImports(filepath, errors, compTarget, libdirs)
             compilationOptions.slowCodegenWarnings = slowCodegenWarnings
             compilationOptions.optimize = optimize
             programAst = ast
             importedFiles = imported
             processAst(programAst, errors, compilationOptions)
             if (compilationOptions.optimize)
-                optimizeAst(programAst, errors, BuiltinFunctionsFacade(BuiltinFunctions), compTarget)
+                optimizeAst(programAst, errors, BuiltinFunctionsFacade(BuiltinFunctions), compTarget, compilationOptions)
             postprocessAst(programAst, errors, compilationOptions)
 
             // printAst(programAst)
@@ -157,7 +158,7 @@ private class BuiltinFunctionsFacade(functions: Map<String, FSignature>): IBuilt
                 }
             }
             else if(func.known_returntype==null)
-                throw IllegalArgumentException("builtin function $name can't be used here because it doesn't return a value")
+                return null  // builtin function $name can't be used here because it doesn't return a value
         }
         return null
     }
@@ -165,14 +166,18 @@ private class BuiltinFunctionsFacade(functions: Map<String, FSignature>): IBuilt
         builtinFunctionReturnType(name, args, program)
 }
 
-private fun parseImports(filepath: Path, errors: IErrorReporter, compTarget: ICompilationTarget): Triple<Program, CompilationOptions, List<Path>> {
+private fun parseImports(filepath: Path,
+                         errors: IErrorReporter,
+                         compTarget: ICompilationTarget,
+                         libdirs: List<String>): Triple<Program, CompilationOptions, List<Path>> {
     val compilationTargetName = compTarget.name
     println("Compiler target: $compilationTargetName. Parsing...")
-    val importer = ModuleImporter()
     val bf = BuiltinFunctionsFacade(BuiltinFunctions)
     val programAst = Program(moduleName(filepath.fileName), mutableListOf(), bf, compTarget)
     bf.program = programAst
-    importer.importModule(programAst, filepath, compTarget, compilationTargetName)
+
+    val importer = ModuleImporter(programAst, compTarget, compilationTargetName, libdirs)
+    importer.importModule(filepath)
     errors.report()
 
     val importedFiles = programAst.modules.filter { !it.source.startsWith("@embedded@") }.map { it.source }
@@ -182,11 +187,11 @@ private fun parseImports(filepath: Path, errors: IErrorReporter, compTarget: ICo
 
     // depending on the machine and compiler options we may have to include some libraries
     for(lib in compTarget.machine.importLibs(compilerOptions, compilationTargetName))
-        importer.importLibraryModule(programAst, lib, compTarget, compilationTargetName)
+        importer.importLibraryModule(lib)
 
     // always import prog8_lib and math
-    importer.importLibraryModule(programAst, "math", compTarget, compilationTargetName)
-    importer.importLibraryModule(programAst, "prog8_lib", compTarget, compilationTargetName)
+    importer.importLibraryModule("math")
+    importer.importLibraryModule("prog8_lib")
     errors.report()
     return Triple(programAst, compilerOptions, importedFiles)
 }
@@ -194,58 +199,59 @@ private fun parseImports(filepath: Path, errors: IErrorReporter, compTarget: ICo
 private fun determineCompilationOptions(program: Program, compTarget: ICompilationTarget): CompilationOptions {
     val mainModule = program.mainModule
     val outputType = (mainModule.statements.singleOrNull { it is Directive && it.directive == "%output" }
-            as? Directive)?.args?.single()?.name?.toUpperCase()
+            as? Directive)?.args?.single()?.name?.uppercase()
     val launcherType = (mainModule.statements.singleOrNull { it is Directive && it.directive == "%launcher" }
-            as? Directive)?.args?.single()?.name?.toUpperCase()
+            as? Directive)?.args?.single()?.name?.uppercase()
     val zpoption: String? = (mainModule.statements.singleOrNull { it is Directive && it.directive == "%zeropage" }
-            as? Directive)?.args?.single()?.name?.toUpperCase()
-    val allOptions = program.modules.flatMap { it.statements }.filter { it is Directive && it.directive == "%option" }.flatMap { (it as Directive).args }.toSet()
+            as? Directive)?.args?.single()?.name?.uppercase()
+    val allOptions = program.modules.flatMap { it.statements }.filter { it is Directive && it.directive == "%option" }
+        .flatMap { (it as Directive).args }.toSet()
     val floatsEnabled = allOptions.any { it.name == "enable_floats" }
     val noSysInit = allOptions.any { it.name == "no_sysinit" }
     var zpType: ZeropageType =
-            if (zpoption == null)
-                if(floatsEnabled) ZeropageType.FLOATSAFE else ZeropageType.KERNALSAFE
-            else
-                try {
-                    ZeropageType.valueOf(zpoption)
-                } catch (x: IllegalArgumentException) {
-                    ZeropageType.KERNALSAFE
-                    // error will be printed by the astchecker
-                }
+        if (zpoption == null)
+            if (floatsEnabled) ZeropageType.FLOATSAFE else ZeropageType.KERNALSAFE
+        else
+            try {
+                ZeropageType.valueOf(zpoption)
+            } catch (x: IllegalArgumentException) {
+                ZeropageType.KERNALSAFE
+                // error will be printed by the astchecker
+            }
 
-    if (zpType==ZeropageType.FLOATSAFE && compTarget.name == Cx16Target.name) {
-        System.err.println("Warning: Cx16 target must use zp option basicsafe instead of floatsafe")
+    if (zpType == ZeropageType.FLOATSAFE && compTarget.name == Cx16Target.name) {
+        System.err.println("Warning: zp option floatsafe changed to basicsafe for cx16 target")
         zpType = ZeropageType.BASICSAFE
     }
 
     val zpReserved = mainModule.statements
-            .asSequence()
-            .filter { it is Directive && it.directive == "%zpreserved" }
-            .map { (it as Directive).args }
-            .map { it[0].int!!..it[1].int!! }
-            .toList()
+        .asSequence()
+        .filter { it is Directive && it.directive == "%zpreserved" }
+        .map { (it as Directive).args }
+        .map { it[0].int!!..it[1].int!! }
+        .toList()
 
-    if(outputType!=null && !OutputType.values().any {it.name==outputType}) {
+    if (outputType != null && !OutputType.values().any { it.name == outputType }) {
         System.err.println("invalid output type $outputType")
         exitProcess(1)
     }
-    if(launcherType!=null && !LauncherType.values().any {it.name==launcherType}) {
+    if (launcherType != null && !LauncherType.values().any { it.name == launcherType }) {
         System.err.println("invalid launcher type $launcherType")
         exitProcess(1)
     }
 
     return CompilationOptions(
-            if (outputType == null) OutputType.PRG else OutputType.valueOf(outputType),
-            if (launcherType == null) LauncherType.BASIC else LauncherType.valueOf(launcherType),
-            zpType, zpReserved, floatsEnabled, noSysInit,
-            compTarget
+        if (outputType == null) OutputType.PRG else OutputType.valueOf(outputType),
+        if (launcherType == null) LauncherType.BASIC else LauncherType.valueOf(launcherType),
+        zpType, zpReserved, floatsEnabled, noSysInit,
+        compTarget
     )
 }
 
 private fun processAst(programAst: Program, errors: IErrorReporter, compilerOptions: CompilationOptions) {
     // perform initial syntax checks and processings
     println("Processing for target ${compilerOptions.compTarget.name}...")
-    programAst.checkIdentifiers(errors, compilerOptions.compTarget)
+    programAst.checkIdentifiers(errors, compilerOptions)
     errors.report()
     programAst.constantFold(errors, compilerOptions.compTarget)
     errors.report()
@@ -253,40 +259,54 @@ private fun processAst(programAst: Program, errors: IErrorReporter, compilerOpti
     errors.report()
     programAst.addTypecasts(errors)
     errors.report()
-    programAst.variousCleanups()
+    programAst.variousCleanups(programAst, errors)
+    errors.report()
     programAst.checkValid(compilerOptions, errors, compilerOptions.compTarget)
     errors.report()
-    programAst.checkIdentifiers(errors, compilerOptions.compTarget)
+    programAst.checkIdentifiers(errors, compilerOptions)
     errors.report()
 }
 
-private fun optimizeAst(programAst: Program, errors: IErrorReporter, functions: IBuiltinFunctions, compTarget: ICompilationTarget) {
+private fun optimizeAst(programAst: Program, errors: IErrorReporter, functions: IBuiltinFunctions, compTarget: ICompilationTarget, options: CompilationOptions) {
     // optimize the parse tree
     println("Optimizing...")
+
+    val remover = UnusedCodeRemover(programAst, errors, compTarget)
+    remover.visit(programAst)
+    remover.applyModifications()
+
     while (true) {
         // keep optimizing expressions and statements until no more steps remain
         val optsDone1 = programAst.simplifyExpressions()
         val optsDone2 = programAst.splitBinaryExpressions(compTarget)
-        val optsDone3 = programAst.optimizeStatements(errors, functions, compTarget, ::loadAsmIncludeFile)
+        val optsDone3 = programAst.optimizeStatements(errors, functions, compTarget)
         programAst.constantFold(errors, compTarget) // because simplified statements and expressions can result in more constants that can be folded away
         errors.report()
         if (optsDone1 + optsDone2 + optsDone3 == 0)
             break
     }
 
-    val remover = UnusedCodeRemover(programAst, errors, compTarget, ::loadAsmIncludeFile)
-    remover.visit(programAst)
-    remover.applyModifications()
+    val inliner = SubroutineInliner(programAst, errors, options)
+    inliner.visit(programAst)
+    errors.report()
+    if(errors.noErrors()) {
+        inliner.applyModifications()
+        inliner.fixCallsToInlinedSubroutines()
+        val remover2 = UnusedCodeRemover(programAst, errors, compTarget)
+        remover2.visit(programAst)
+        remover2.applyModifications()
+    }
+
     errors.report()
 }
 
 private fun postprocessAst(programAst: Program, errors: IErrorReporter, compilerOptions: CompilationOptions) {
     programAst.addTypecasts(errors)
     errors.report()
-    programAst.variousCleanups()
+    programAst.variousCleanups(programAst, errors)
     programAst.checkValid(compilerOptions, errors, compilerOptions.compTarget)          // check if final tree is still valid
     errors.report()
-    val callGraph = CallGraph(programAst, ::loadAsmIncludeFile)
+    val callGraph = CallGraph(programAst)
     callGraph.checkRecursiveCalls(errors)
     errors.report()
     programAst.verifyFunctionArgTypes()
@@ -297,7 +317,7 @@ private fun writeAssembly(programAst: Program,
                           errors: IErrorReporter,
                           outputDir: Path,
                           compilerOptions: CompilationOptions): String {
-    // asm generation directly from the Ast,
+    // asm generation directly from the Ast
     programAst.processAstBeforeAsmGeneration(errors, compilerOptions.compTarget)
     errors.report()
 

compiler/src/prog8/compiler/ErrorReporting.kt

@@ -7,7 +7,7 @@ import prog8.parser.ParsingFailedError
 interface IErrorReporter {
     fun err(msg: String, position: Position)
     fun warn(msg: String, position: Position)
-    fun isEmpty(): Boolean
+    fun noErrors(): Boolean
     fun report()
 }
 
@@ -53,5 +53,5 @@ internal class ErrorReporter: IErrorReporter {
             throw ParsingFailedError("There are $numErrors errors and $numWarnings warnings.")
     }
 
-    override fun isEmpty() = messages.isEmpty()
+    override fun noErrors() = messages.none { it.severity==MessageSeverity.ERROR }
 }

compiler/src/prog8/compiler/Zeropage.kt

@@ -19,7 +19,29 @@ abstract class Zeropage(protected val options: CompilationOptions) {
 
     val allowedDatatypes = NumericDatatypes
 
-    fun available() = if(options.zeropage==ZeropageType.DONTUSE) 0 else free.size
+    fun availableBytes() = if(options.zeropage==ZeropageType.DONTUSE) 0 else free.size
+    fun hasByteAvailable() = if(options.zeropage==ZeropageType.DONTUSE) false else free.isNotEmpty()
+    fun availableWords(): Int {
+        if(options.zeropage==ZeropageType.DONTUSE)
+            return 0
+
+        val words = free.windowed(2).filter { it[0] == it[1]-1 }
+        var nonOverlappingWordsCount = 0
+        var prevMsbLoc = -1
+        for(w in words) {
+            if(w[0]!=prevMsbLoc) {
+                nonOverlappingWordsCount++
+                prevMsbLoc = w[1]
+            }
+        }
+        return nonOverlappingWordsCount
+    }
+    fun hasWordAvailable(): Boolean {
+        if(options.zeropage==ZeropageType.DONTUSE)
+            return false
+
+        return free.windowed(2).any { it[0] == it[1] - 1 }
+    }
 
     fun allocate(scopedname: String, datatype: DataType, position: Position?, errors: IErrorReporter): Int {
         assert(scopedname.isEmpty() || !allocations.values.any { it.first==scopedname } ) {"scopedname can't be allocated twice"}

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

@@ -9,12 +9,15 @@ import prog8.ast.statements.*
 import prog8.ast.walk.IAstVisitor
 import prog8.compiler.CompilationOptions
 import prog8.compiler.IErrorReporter
+import prog8.compiler.ZeropageType
 import prog8.compiler.functions.BuiltinFunctions
 import prog8.compiler.functions.builtinFunctionReturnType
 import prog8.compiler.target.C64Target
 import prog8.compiler.target.Cx16Target
 import prog8.compiler.target.ICompilationTarget
+import java.io.CharConversionException
 import java.io.File
+import java.util.*
 
 internal class AstChecker(private val program: Program,
                           private val compilerOptions: CompilationOptions,
@@ -41,6 +44,11 @@ internal class AstChecker(private val program: Program,
             }
         }
 
+        if(compilerOptions.floats) {
+            if (compilerOptions.zeropage !in setOf(ZeropageType.FLOATSAFE, ZeropageType.BASICSAFE, ZeropageType.DONTUSE ))
+                errors.err("when floats are enabled, zero page type should be 'floatsafe' or 'basicsafe' or 'dontuse'", program.mainModule.position)
+        }
+
         super.visit(program)
     }
 
@@ -70,9 +78,9 @@ internal class AstChecker(private val program: Program,
         if(expectedReturnValues.size==1 && returnStmt.value!=null) {
             val valueDt = returnStmt.value!!.inferType(program)
             if(!valueDt.isKnown) {
-                errors.err("return value type mismatch", returnStmt.value!!.position)
+                errors.err("return value type mismatch or unknown symbol", returnStmt.value!!.position)
             } else {
-                if (expectedReturnValues[0] != valueDt.typeOrElse(DataType.STRUCT))
+                if (expectedReturnValues[0] != valueDt.typeOrElse(DataType.UNDEFINED))
                     errors.err("type $valueDt of return value doesn't match subroutine's return type ${expectedReturnValues[0]}", returnStmt.value!!.position)
             }
         }
@@ -80,12 +88,24 @@ internal class AstChecker(private val program: Program,
     }
 
     override fun visit(ifStatement: IfStatement) {
-        if(ifStatement.condition.inferType(program).typeOrElse(DataType.STRUCT) !in IntegerDatatypes)
+        if(!ifStatement.condition.inferType(program).isInteger())
             errors.err("condition value should be an integer type", ifStatement.condition.position)
         super.visit(ifStatement)
     }
 
     override fun visit(forLoop: ForLoop) {
+
+        fun checkUnsignedLoopDownto0(range: RangeExpr?) {
+            if(range==null)
+                return
+            val step = range.step.constValue(program)?.number?.toDouble() ?: 1.0
+            if(step < -1.0) {
+                val limit = range.to.constValue(program)?.number?.toDouble()
+                if(limit==0.0 && range.from.constValue(program)==null)
+                    errors.err("for unsigned loop variable it's not possible to count down with step != -1 from a non-const value to exactly zero due to value wrapping", forLoop.position)
+            }
+        }
+
         val iterableDt = forLoop.iterable.inferType(program).typeOrElse(DataType.BYTE)
         if(iterableDt !in IterableDatatypes && forLoop.iterable !is RangeExpr) {
             errors.err("can only loop over an iterable type", forLoop.position)
@@ -98,11 +118,15 @@ internal class AstChecker(private val program: Program,
                     DataType.UBYTE -> {
                         if(iterableDt!= DataType.UBYTE && iterableDt!= DataType.ARRAY_UB && iterableDt != DataType.STR)
                             errors.err("ubyte loop variable can only loop over unsigned bytes or strings", forLoop.position)
+
+                        checkUnsignedLoopDownto0(forLoop.iterable as? RangeExpr)
                     }
                     DataType.UWORD -> {
                         if(iterableDt!= DataType.UBYTE && iterableDt!= DataType.UWORD && iterableDt != DataType.STR &&
                                 iterableDt != DataType.ARRAY_UB && iterableDt!= DataType.ARRAY_UW)
                             errors.err("uword loop variable can only loop over unsigned bytes, words or strings", forLoop.position)
+
+                        checkUnsignedLoopDownto0(forLoop.iterable as? RangeExpr)
                     }
                     DataType.BYTE -> {
                         if(iterableDt!= DataType.BYTE && iterableDt!= DataType.ARRAY_B)
@@ -118,7 +142,7 @@ internal class AstChecker(private val program: Program,
                     }
                     else -> errors.err("loop variable must be numeric type", forLoop.position)
                 }
-                if(errors.isEmpty()) {
+                if(errors.noErrors()) {
                     // check loop range values
                     val range = forLoop.iterable as? RangeExpr
                     if(range!=null) {
@@ -140,6 +164,7 @@ internal class AstChecker(private val program: Program,
         super.visit(forLoop)
     }
 
+
     override fun visit(jump: Jump) {
         val ident = jump.identifier
         if(ident!=null) {
@@ -190,6 +215,28 @@ internal class AstChecker(private val program: Program,
         super.visit(label)
     }
 
+    private fun hasReturnOrJump(scope: INameScope): Boolean {
+        class Searcher: IAstVisitor
+        {
+            var count=0
+
+            override fun visit(returnStmt: Return) {
+                count++
+            }
+            override fun visit(jump: Jump) {
+                count++
+            }
+        }
+
+        val s=Searcher()
+        for(stmt in scope.statements) {
+            stmt.accept(s)
+            if(s.count>0)
+                return true
+        }
+        return s.count > 0
+    }
+
     override fun visit(subroutine: Subroutine) {
         fun err(msg: String) = errors.err(msg, subroutine.position)
 
@@ -203,13 +250,6 @@ internal class AstChecker(private val program: Program,
         if(uniqueNames.size!=subroutine.parameters.size)
             err("parameter names must be unique")
 
-        if(subroutine.inline) {
-            if (subroutine.containsDefinedVariables())
-                err("can't inline a subroutine that defines variables")
-            if (!subroutine.isAsmSubroutine && subroutine.parameters.isNotEmpty())
-                err("can't inline a non-asm subroutine that has parameters")
-        }
-
         super.visit(subroutine)
 
         // user-defined subroutines can only have zero or one return type
@@ -218,13 +258,13 @@ internal class AstChecker(private val program: Program,
             err("subroutines can only have one return value")
 
         // subroutine must contain at least one 'return' or 'goto'
-        // (or if it has an asm block, that must contain a 'rts' or 'jmp')
-        if(subroutine.statements.count { it is Return || it is Jump } == 0) {
+        // (or if it has an asm block, that must contain a 'rts' or 'jmp' or 'bra')
+        if(!hasReturnOrJump(subroutine)) {
             if (subroutine.amountOfRtsInAsm() == 0) {
                 if (subroutine.returntypes.isNotEmpty()) {
                     // for asm subroutines with an address, no statement check is possible.
                     if (subroutine.asmAddress == null && !subroutine.inline)
-                        err("non-inline subroutine has result value(s) and thus must have at least one 'return' or 'goto' in it (or 'rts' / 'jmp' in case of %asm)")
+                        err("non-inline subroutine has result value(s) and thus must have at least one 'return' or 'goto' in it (or rts/jmp/bra in case of %asm)")
                 }
             }
         }
@@ -348,13 +388,13 @@ internal class AstChecker(private val program: Program,
     }
 
     override fun visit(untilLoop: UntilLoop) {
-        if(untilLoop.condition.inferType(program).typeOrElse(DataType.STRUCT) !in IntegerDatatypes)
+        if(!untilLoop.condition.inferType(program).isInteger())
             errors.err("condition value should be an integer type", untilLoop.condition.position)
         super.visit(untilLoop)
     }
 
     override fun visit(whileLoop: WhileLoop) {
-        if(whileLoop.condition.inferType(program).typeOrElse(DataType.STRUCT) !in IntegerDatatypes)
+        if(!whileLoop.condition.inferType(program).isInteger())
             errors.err("condition value should be an integer type", whileLoop.condition.position)
         super.visit(whileLoop)
     }
@@ -374,43 +414,19 @@ internal class AstChecker(private val program: Program,
                 if(!idt.isKnown) {
                      errors.err("return type mismatch", assignment.value.position)
                 }
-                if(stmt.returntypes.size <= 1 && stmt.returntypes.single() isNotAssignableTo idt.typeOrElse(DataType.BYTE)) {
+                if(stmt.returntypes.isEmpty() || (stmt.returntypes.size == 1 && stmt.returntypes.single() isNotAssignableTo idt.typeOrElse(DataType.BYTE))) {
                     errors.err("return type mismatch", assignment.value.position)
                 }
             }
         }
 
-        val targetIdent = assignment.target.identifier
-        if(targetIdent!=null) {
-            val targetVar = targetIdent.targetVarDecl(program)
-            if(targetVar?.struct != null) {
-                val sourceStructLv = assignment.value as? ArrayLiteralValue
-                if (sourceStructLv != null) {
-                    if (sourceStructLv.value.size != targetVar.struct?.numberOfElements)
-                        errors.err("number of elements doesn't match struct definition", sourceStructLv.position)
-                } else {
-                    val sourceIdent = assignment.value as? IdentifierReference
-                    if (sourceIdent != null) {
-                        val sourceVar = sourceIdent.targetVarDecl(program)
-                        if (sourceVar?.struct != null) {
-                            if (sourceVar.struct !== targetVar.struct)
-                                errors.err("assignment of different struct types", assignment.position)
-                        } else if(sourceVar?.isArray==true) {
-                            if((sourceVar.value as ArrayLiteralValue).value.size != targetVar.struct?.numberOfElements)
-                                errors.err("number of elements doesn't match struct definition", sourceVar.position)
-                        }
-                    }
-                }
-            }
-        }
-
         val targetDt = assignment.target.inferType(program)
         val valueDt = assignment.value.inferType(program)
         if(valueDt.isKnown && !(valueDt isAssignableTo targetDt)) {
-            if(targetDt.typeOrElse(DataType.STRUCT) in IterableDatatypes)
+            if(targetDt.isIterable())
                 errors.err("cannot assign value to string or array", assignment.value.position)
             else if(!(valueDt.istype(DataType.STR) && targetDt.istype(DataType.UWORD)))
-                errors.err("value's type doesn't match target", assignment.value.position)
+                errors.err("type of value doesn't match target", assignment.value.position)
         }
 
         if(assignment.value is TypecastExpression) {
@@ -480,12 +496,8 @@ internal class AstChecker(private val program: Program,
 
     override fun visit(addressOf: AddressOf) {
         val variable=addressOf.identifier.targetVarDecl(program)
-        if(variable!=null
-            && variable.datatype !in ArrayDatatypes
-            && variable.type!=VarDeclType.MEMORY
-            && variable.struct == null
-            && variable.datatype != DataType.STR && variable.datatype!=DataType.STRUCT)
-                errors.err("invalid pointer-of operand type", addressOf.position)
+        if(variable!=null && variable.type==VarDeclType.CONST)
+            errors.err("invalid pointer-of operand type", addressOf.position)
         super.visit(addressOf)
     }
 
@@ -493,7 +505,7 @@ internal class AstChecker(private val program: Program,
         fun err(msg: String, position: Position?=null) = errors.err(msg, position ?: decl.position)
 
         // the initializer value can't refer to the variable itself (recursive definition)
-        if(decl.value?.referencesIdentifier(decl.name) == true || decl.arraysize?.indexVar?.referencesIdentifier(decl.name) == true)
+        if(decl.value?.referencesIdentifier(decl.name) == true || decl.arraysize?.indexExpr?.referencesIdentifier(decl.name) == true)
             err("recursive var declaration")
 
         // CONST can only occur on simple types (byte, word, float)
@@ -527,17 +539,6 @@ internal class AstChecker(private val program: Program,
 
         when(decl.type) {
             VarDeclType.VAR, VarDeclType.CONST -> {
-                if(decl.datatype==DataType.STRUCT) {
-                    if(decl.struct==null)
-                        throw FatalAstException("struct vardecl should be linked to its struct $decl")
-                    if(decl.zeropage==ZeropageWish.PREFER_ZEROPAGE || decl.zeropage==ZeropageWish.REQUIRE_ZEROPAGE)
-                        err("struct can not be in zeropage")
-                }
-                if(decl.struct!=null) {
-                    if(decl.zeropage==ZeropageWish.PREFER_ZEROPAGE || decl.zeropage==ZeropageWish.REQUIRE_ZEROPAGE)
-                        err("struct can not be in zeropage")
-                }
-
                 when(decl.value) {
                     null -> {
                         // a vardecl without an initial value, don't bother with it
@@ -547,30 +548,8 @@ internal class AstChecker(private val program: Program,
                         checkValueTypeAndRangeString(decl.datatype, decl.value as StringLiteralValue)
                     }
                     is ArrayLiteralValue -> {
-                        if(decl.datatype==DataType.STRUCT) {
-                            val struct = decl.struct!!
-                            val structLv = decl.value as ArrayLiteralValue
-                            if(struct.numberOfElements != structLv.value.size) {
-                                errors.err("struct value has incorrect number of elements", structLv.position)
-                                return
-                            }
-                            for(value in structLv.value.zip(struct.statements)) {
-                                val memberdecl = value.second as VarDecl
-                                val constValue = value.first.constValue(program)
-                                if(constValue==null) {
-                                    errors.err("struct literal value for field '${memberdecl.name}' should consist of compile-time constants", value.first.position)
-                                    return
-                                }
-                                val memberDt = memberdecl.datatype
-                                if(!checkValueTypeAndRange(memberDt, constValue)) {
-                                    errors.err("struct member value's type is not compatible with member field '${memberdecl.name}'", value.first.position)
-                                    return
-                                }
-                            }
-                        } else {
-                            val arraySpec = decl.arraysize ?: ArrayIndex.forArray(decl.value as ArrayLiteralValue)
-                            checkValueTypeAndRangeArray(decl.datatype, decl.struct, arraySpec, decl.value as ArrayLiteralValue)
-                        }
+                        val arraySpec = decl.arraysize ?: ArrayIndex.forArray(decl.value as ArrayLiteralValue)
+                        checkValueTypeAndRangeArray(decl.datatype, arraySpec, decl.value as ArrayLiteralValue)
                     }
                     is NumericLiteralValue -> {
                         checkValueTypeAndRange(decl.datatype, decl.value as NumericLiteralValue)
@@ -585,8 +564,9 @@ internal class AstChecker(private val program: Program,
                 }
             }
             VarDeclType.MEMORY -> {
-                if(decl.arraysize!=null) {
-                    val arraySize = decl.arraysize!!.constIndex() ?: 1
+                val arraysize = decl.arraysize
+                if(arraysize!=null) {
+                    val arraySize = arraysize.constIndex() ?: 1
                     when(decl.datatype) {
                         DataType.ARRAY_B, DataType.ARRAY_UB ->
                             if(arraySize > 256)
@@ -600,10 +580,9 @@ internal class AstChecker(private val program: Program,
                         else -> {}
                     }
                 }
-
-                if(decl.value is NumericLiteralValue) {
-                    val value = decl.value as NumericLiteralValue
-                    if (value.type !in IntegerDatatypes || value.number.toInt() < 0 || value.number.toInt() > 65535) {
+                val numvalue = decl.value as? NumericLiteralValue
+                if(numvalue!=null) {
+                    if (numvalue.type !in IntegerDatatypes || numvalue.number.toInt() < 0 || numvalue.number.toInt() > 65535) {
                         err("memory address must be valid integer 0..\$ffff", decl.value?.position)
                     }
                 } else {
@@ -614,23 +593,16 @@ internal class AstChecker(private val program: Program,
 
         val declValue = decl.value
         if(declValue!=null && decl.type==VarDeclType.VAR) {
-            if(decl.datatype==DataType.STRUCT) {
-                val valueIdt = declValue.inferType(program)
-                if(!valueIdt.isKnown)
-                    throw AstException("unknown dt")
-                val valueDt = valueIdt.typeOrElse(DataType.STRUCT)
-                if(valueDt !in ArrayDatatypes)
-                    err("initialisation of struct should be with array value", declValue.position)
-            } else if (!declValue.inferType(program).istype(decl.datatype)) {
+            if (!declValue.inferType(program).istype(decl.datatype)) {
                 err("initialisation value has incompatible type (${declValue.inferType(program)}) for the variable (${decl.datatype})", declValue.position)
             }
         }
 
         // array length limits and constant lenghts
         if(decl.isArray) {
-            val length = decl.arraysize!!.constIndex()
+            val length = decl.arraysize?.constIndex()
             if(length==null)
-                err("array length must be a constant")
+                err("array length must be known at compile-time")
             else {
                 when (decl.datatype) {
                     DataType.STR, DataType.ARRAY_UB, DataType.ARRAY_B -> {
@@ -712,20 +684,20 @@ internal class AstChecker(private val program: Program,
             }
             "%breakpoint" -> {
                 if(directive.parent !is INameScope || directive.parent is Module)
-                    err("this directive may only occur in a block")
+                    err("this directive can't be used here")
                 if(directive.args.isNotEmpty())
                     err("invalid breakpoint directive, expected no arguments")
             }
             "%asminclude" -> {
                 if(directive.parent !is INameScope || directive.parent is Module)
-                    err("this directive may only occur in a block")
-                if(directive.args.size!=2 || directive.args[0].str==null || directive.args[1].str==null)
-                    err("invalid asminclude directive, expected arguments: \"filename\", \"scopelabel\"")
+                    err("this directive can't be used here")
+                if(directive.args.size!=1 || directive.args[0].str==null)
+                    err("invalid asminclude directive, expected argument: \"filename\"")
                 checkFileExists(directive, directive.args[0].str!!)
             }
             "%asmbinary" -> {
                 if(directive.parent !is INameScope || directive.parent is Module)
-                    err("this directive may only occur in a block")
+                    err("this directive can't be used here")
                 val errormsg = "invalid asmbinary directive, expected arguments: \"filename\" [, offset [, length ] ]"
                 if(directive.args.isEmpty()) err(errormsg)
                 else if(directive.args.isNotEmpty() && directive.args[0].str==null) err(errormsg)
@@ -765,11 +737,11 @@ internal class AstChecker(private val program: Program,
 
     override fun visit(array: ArrayLiteralValue) {
         if(array.type.isKnown) {
-            if (!compilerOptions.floats && array.type.typeOrElse(DataType.STRUCT) in setOf(DataType.FLOAT, DataType.ARRAY_F)) {
+            if (!compilerOptions.floats && array.type.typeOrElse(DataType.UNDEFINED) in setOf(DataType.FLOAT, DataType.ARRAY_F)) {
                 errors.err("floating point used, but that is not enabled via options", array.position)
             }
             val arrayspec = ArrayIndex.forArray(array)
-            checkValueTypeAndRangeArray(array.type.typeOrElse(DataType.STRUCT), null, arrayspec, array)
+            checkValueTypeAndRangeArray(array.type.typeOrElse(DataType.UNDEFINED), arrayspec, array)
         }
 
         fun isPassByReferenceElement(e: Expression): Boolean {
@@ -793,6 +765,13 @@ internal class AstChecker(private val program: Program,
 
     override fun visit(string: StringLiteralValue) {
         checkValueTypeAndRangeString(DataType.STR, string)
+
+        try {
+            compTarget.encodeString(string.value, string.altEncoding)
+        } catch (cx: CharConversionException) {
+            errors.err(cx.message ?: "can't encode string", string.position)
+        }
+
         super.visit(string)
     }
 
@@ -801,7 +780,7 @@ internal class AstChecker(private val program: Program,
         if(!idt.isKnown)
             return  // any error should be reported elsewhere
 
-        val dt = idt.typeOrElse(DataType.STRUCT)
+        val dt = idt.typeOrElse(DataType.UNDEFINED)
         if(expr.operator=="-") {
             if (dt != DataType.BYTE && dt != DataType.WORD && dt != DataType.FLOAT) {
                 errors.err("can only take negative of a signed number type", expr.position)
@@ -826,8 +805,8 @@ internal class AstChecker(private val program: Program,
         if(!leftIDt.isKnown || !rightIDt.isKnown)
             return     // hopefully this error will be detected elsewhere
 
-        val leftDt = leftIDt.typeOrElse(DataType.STRUCT)
-        val rightDt = rightIDt.typeOrElse(DataType.STRUCT)
+        val leftDt = leftIDt.typeOrElse(DataType.UNDEFINED)
+        val rightDt = rightIDt.typeOrElse(DataType.UNDEFINED)
 
         when(expr.operator){
             "/", "%" -> {
@@ -953,6 +932,20 @@ internal class AstChecker(private val program: Program,
             }
         }
 
+        // functions that don't return a value, can't be used in an expression or assignment
+        if(targetStatement is Subroutine) {
+            if(targetStatement.returntypes.isEmpty()) {
+                if(functionCall.parent is Expression || functionCall.parent is Assignment)
+                    errors.err("subroutine doesn't return a value", functionCall.position)
+            }
+        }
+        else if(targetStatement is BuiltinFunctionStatementPlaceholder) {
+            if(builtinFunctionReturnType(targetStatement.name, functionCall.args, program).isUnknown) {
+                if(functionCall.parent is Expression || functionCall.parent is Assignment)
+                    errors.err("function doesn't return a value", functionCall.position)
+            }
+        }
+
         super.visit(functionCall)
     }
 
@@ -1014,7 +1007,7 @@ internal class AstChecker(private val program: Program,
                     errors.err("swap requires 2 variables, not constant value(s)", position)
                 else if(args[0] isSameAs args[1])
                     errors.err("swap should have 2 different args", position)
-                else if(dt1.typeOrElse(DataType.STRUCT) !in NumericDatatypes)
+                else if(!dt1.isNumeric())
                     errors.err("swap requires args of numerical type", position)
             }
             else if(target.name=="all" || target.name=="any") {
@@ -1045,7 +1038,7 @@ internal class AstChecker(private val program: Program,
                             ident = fcall.args[0] as? IdentifierReference
                     }
                     if(ident!=null && ident.nameInSource[0] == "cx16" && ident.nameInSource[1].startsWith("r")) {
-                        val reg = RegisterOrPair.valueOf(ident.nameInSource[1].toUpperCase())
+                        val reg = RegisterOrPair.valueOf(ident.nameInSource[1].uppercase())
                         val same = params.filter { it.value.registerOrPair==reg }
                         for(s in same) {
                             if(s.index!=arg.index) {
@@ -1111,22 +1104,15 @@ internal class AstChecker(private val program: Program,
             errors.err("indexing requires a variable to act upon", arrayIndexedExpression.position)
 
         // check index value 0..255
-        val dtxNum = arrayIndexedExpression.indexer.indexNum?.inferType(program)?.typeOrElse(DataType.STRUCT)
-        if(dtxNum!=null && dtxNum != DataType.UBYTE && dtxNum != DataType.BYTE)
+        val dtxNum = arrayIndexedExpression.indexer.indexExpr.inferType(program)
+        if(!dtxNum.istype(DataType.UBYTE) && !dtxNum.istype(DataType.BYTE))
             errors.err("array indexing is limited to byte size 0..255", arrayIndexedExpression.position)
-        val dtxVar = arrayIndexedExpression.indexer.indexVar?.inferType(program)?.typeOrElse(DataType.STRUCT)
-        if(dtxVar!=null && dtxVar != DataType.UBYTE && dtxVar != DataType.BYTE)
-            errors.err("array indexing is limited to byte size 0..255", arrayIndexedExpression.position)
-
-        if(arrayIndexedExpression.indexer.origExpression!=null)
-            throw FatalAstException("array indexer should have been replaced with a temp var @ ${arrayIndexedExpression.indexer.position}")
 
         super.visit(arrayIndexedExpression)
     }
 
     override fun visit(whenStatement: WhenStatement) {
-        val conditionType = whenStatement.condition.inferType(program).typeOrElse(DataType.STRUCT)
-        if(conditionType !in IntegerDatatypes)
+        if(!whenStatement.condition.inferType(program).isInteger())
             errors.err("when condition must be an integer value", whenStatement.position)
         val tally = mutableSetOf<Int>()
         for((choices, choiceNode) in whenStatement.choiceValues(program)) {
@@ -1157,7 +1143,7 @@ internal class AstChecker(private val program: Program,
                 when {
                     constvalue == null -> errors.err("choice value must be a constant", whenChoice.position)
                     constvalue.type !in IntegerDatatypes -> errors.err("choice value must be a byte or word", whenChoice.position)
-                    constvalue.type != conditionType.typeOrElse(DataType.STRUCT) -> errors.err("choice value datatype differs from condition value", whenChoice.position)
+                    constvalue.type != conditionType.typeOrElse(DataType.UNDEFINED) -> errors.err("choice value datatype differs from condition value", whenChoice.position)
                 }
             }
         } else {
@@ -1167,24 +1153,6 @@ internal class AstChecker(private val program: Program,
         super.visit(whenChoice)
     }
 
-    override fun visit(structDecl: StructDecl) {
-        // a struct can only contain 1 or more vardecls and can not be nested
-        if(structDecl.statements.isEmpty())
-            errors.err("struct must contain at least one member", structDecl.position)
-
-        for(member in structDecl.statements){
-            val decl = member as? VarDecl
-            if(decl==null)
-                errors.err("struct can only contain variable declarations", structDecl.position)
-            else {
-                if(decl.zeropage==ZeropageWish.REQUIRE_ZEROPAGE || decl.zeropage==ZeropageWish.PREFER_ZEROPAGE)
-                    errors.err("struct can not contain zeropage members", decl.position)
-                if(decl.datatype !in NumericDatatypes)
-                    errors.err("structs can only contain numerical types", decl.position)
-            }
-        }
-    }
-
     private fun checkFunctionOrLabelExists(target: IdentifierReference, statement: Statement): Statement? {
         val targetStatement = target.targetStatement(program)
         if(targetStatement is Label || targetStatement is Subroutine || targetStatement is BuiltinFunctionStatementPlaceholder)
@@ -1208,8 +1176,7 @@ internal class AstChecker(private val program: Program,
         else false
     }
 
-    private fun checkValueTypeAndRangeArray(targetDt: DataType, struct: StructDecl?,
-                                            arrayspec: ArrayIndex, value: ArrayLiteralValue) : Boolean {
+    private fun checkValueTypeAndRangeArray(targetDt: DataType, arrayspec: ArrayIndex, value: ArrayLiteralValue) : Boolean {
         fun err(msg: String) : Boolean {
             errors.err(msg, value.position)
             return false
@@ -1282,22 +1249,6 @@ internal class AstChecker(private val program: Program,
                 }
                 return err("invalid float array initialization value ${value.type}, expected $targetDt")
             }
-            DataType.STRUCT -> {
-                if(value.type.typeOrElse(DataType.STRUCT) in ArrayDatatypes) {
-                    if(value.value.size != struct!!.numberOfElements)
-                        return err("number of values is not the same as the number of members in the struct")
-                    for(elt in value.value.zip(struct.statements)) {
-                        val vardecl = elt.second as VarDecl
-                        val valuetype = elt.first.inferType(program)
-                        if (!valuetype.isKnown || valuetype isNotAssignableTo vardecl.datatype) {
-                            errors.err("invalid struct member init value type $valuetype, expected ${vardecl.datatype}", elt.first.position)
-                            return false
-                        }
-                    }
-                    return true
-                }
-                return false
-            }
             else -> return false
         }
     }
@@ -1400,15 +1351,6 @@ internal class AstChecker(private val program: Program,
             DataType.UWORD -> sourceDatatype== DataType.UBYTE || sourceDatatype== DataType.UWORD
             DataType.FLOAT -> sourceDatatype in NumericDatatypes
             DataType.STR -> sourceDatatype== DataType.STR
-            DataType.STRUCT -> {
-                if(sourceDatatype==DataType.STRUCT) {
-                    val structLv = sourceValue as ArrayLiteralValue
-                    val numValues = structLv.value.size
-                    val targetstruct = target.identifier!!.targetVarDecl(program)!!.struct!!
-                    return targetstruct.numberOfElements == numValues
-                }
-                false
-            }
             else -> {
                 errors.err("cannot assign new value to variable of type $targetDatatype", position)
                 false
@@ -1422,10 +1364,15 @@ internal class AstChecker(private val program: Program,
             errors.err("cannot assign word to byte, use msb() or lsb()?", position)
         }
         else if(sourceDatatype== DataType.FLOAT && targetDatatype in IntegerDatatypes)
-            errors.err("cannot assign float to ${targetDatatype.name.toLowerCase()}; possible loss of precision. Suggestion: round the value or revert to integer arithmetic", position)
+            errors.err("cannot assign float to ${targetDatatype.name.lowercase()}; possible loss of precision. Suggestion: round the value or revert to integer arithmetic", position)
         else {
             if(targetDatatype!=DataType.UWORD && sourceDatatype !in PassByReferenceDatatypes)
-                errors.err("cannot assign ${sourceDatatype.name.toLowerCase()} to ${targetDatatype.name.toLowerCase()}", position)
+                errors.err(
+                    "cannot assign ${sourceDatatype.name.lowercase()} to ${
+                        targetDatatype.name.lowercase(
+                            Locale.getDefault()
+                        )
+                    }", position)
         }
 
 

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

@@ -17,13 +17,20 @@ internal fun Program.checkValid(compilerOptions: CompilationOptions, errors: IEr
 internal fun Program.processAstBeforeAsmGeneration(errors: IErrorReporter, compTarget: ICompilationTarget) {
     val fixer = BeforeAsmGenerationAstChanger(this, errors, compTarget)
     fixer.visit(this)
-    fixer.applyModifications()
+    while(errors.noErrors() && fixer.applyModifications()>0) {
+        fixer.visit(this)
+    }
 }
 
 internal fun Program.reorderStatements(errors: IErrorReporter) {
     val reorder = StatementReorderer(this, errors)
     reorder.visit(this)
-    reorder.applyModifications()
+    if(errors.noErrors()) {
+        reorder.applyModifications()
+        reorder.visit(this)
+        if(errors.noErrors())
+            reorder.applyModifications()
+    }
 }
 
 internal fun Program.addTypecasts(errors: IErrorReporter) {
@@ -37,12 +44,12 @@ internal fun Program.verifyFunctionArgTypes() {
     fixer.visit(this)
 }
 
-internal fun Program.checkIdentifiers(errors: IErrorReporter, compTarget: ICompilationTarget) {
+internal fun Program.checkIdentifiers(errors: IErrorReporter, options: CompilationOptions) {
 
-    val checker2 = AstIdentifiersChecker(this, errors, compTarget)
+    val checker2 = AstIdentifiersChecker(this, errors, options.compTarget)
     checker2.visit(this)
 
-    if(errors.isEmpty()) {
+    if(errors.noErrors()) {
         val transforms = AstVariousTransforms(this)
         transforms.visit(this)
         transforms.applyModifications()
@@ -56,12 +63,14 @@ internal fun Program.checkIdentifiers(errors: IErrorReporter, compTarget: ICompi
     }
 }
 
-internal fun Program.variousCleanups() {
-    val process = VariousCleanups()
+internal fun Program.variousCleanups(program: Program, errors: IErrorReporter) {
+    val process = VariousCleanups(program, errors)
     process.visit(this)
-    process.applyModifications()
+    if(errors.noErrors())
+        process.applyModifications()
 }
 
+
 internal fun Program.moveMainAndStartToFirst() {
     // the module containing the program entrypoint is moved to the first in the sequence.
     // the "main" block containing the entrypoint is moved to the top in there,
@@ -69,29 +78,27 @@ internal fun Program.moveMainAndStartToFirst() {
 
     val directives = modules[0].statements.filterIsInstance<Directive>()
     val start = this.entrypoint()
-    if(start!=null) {
-        val mod = start.definingModule()
-        val block = start.definingBlock()
-        if(!modules.remove(mod))
-            throw FatalAstException("module wrong")
-        modules.add(0, mod)
-        mod.remove(block)
-        var afterDirective = mod.statements.indexOfFirst { it !is Directive }
-        if(afterDirective<0)
-            mod.statements.add(block)
-        else
-            mod.statements.add(afterDirective, block)
-        block.remove(start)
-        afterDirective = block.statements.indexOfFirst { it !is Directive }
-        if(afterDirective<0)
-            block.statements.add(start)
-        else
-            block.statements.add(afterDirective, start)
+    val mod = start.definingModule()
+    val block = start.definingBlock()
+    if(!modules.remove(mod))
+        throw FatalAstException("module wrong")
+    modules.add(0, mod)
+    mod.remove(block)
+    var afterDirective = mod.statements.indexOfFirst { it !is Directive }
+    if(afterDirective<0)
+        mod.statements.add(block)
+    else
+        mod.statements.add(afterDirective, block)
+    block.remove(start)
+    afterDirective = block.statements.indexOfFirst { it !is Directive }
+    if(afterDirective<0)
+        block.statements.add(start)
+    else
+        block.statements.add(afterDirective, start)
 
-        // overwrite the directives in the module containing the entrypoint
-        for(directive in directives) {
-            modules[0].statements.removeAll { it is Directive && it.directive == directive.directive }
-            modules[0].statements.add(0, directive)
-        }
+    // overwrite the directives in the module containing the entrypoint
+    for(directive in directives) {
+        modules[0].statements.removeAll { it is Directive && it.directive == directive.directive }
+        modules[0].statements.add(0, directive)
     }
 }

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

@@ -2,11 +2,7 @@ package prog8.compiler.astprocessing
 
 import prog8.ast.Module
 import prog8.ast.Program
-import prog8.ast.base.DataType
-import prog8.ast.base.NumericDatatypes
 import prog8.ast.base.Position
-import prog8.ast.expressions.ArrayLiteralValue
-import prog8.ast.expressions.NumericLiteralValue
 import prog8.ast.expressions.StringLiteralValue
 import prog8.ast.statements.*
 import prog8.ast.walk.IAstVisitor
@@ -66,29 +62,6 @@ internal class AstIdentifiersChecker(private val program: Program, private val e
         if(decl.name in compTarget.machine.opcodeNames)
             errors.err("can't use a cpu opcode name as a symbol: '${decl.name}'", decl.position)
 
-        if(decl.datatype==DataType.STRUCT) {
-            if (decl.structHasBeenFlattened)
-                return super.visit(decl)    // don't do this multiple times
-
-            if (decl.struct == null) {
-                errors.err("undefined struct type", decl.position)
-                return super.visit(decl)
-            }
-
-            if (decl.struct!!.statements.any { (it as VarDecl).datatype !in NumericDatatypes })
-                return super.visit(decl)     // a non-numeric member, not supported. proper error is given by AstChecker later
-
-            if (decl.value is NumericLiteralValue) {
-                errors.err("you cannot initialize a struct using a single value", decl.position)
-                return super.visit(decl)
-            }
-
-            if (decl.value != null && decl.value !is ArrayLiteralValue) {
-                errors.err("initializing a struct requires array literal value", decl.value?.position ?: decl.position)
-                return super.visit(decl)
-            }
-        }
-
         val existing = program.namespace.lookup(listOf(decl.name), decl)
         if (existing != null && existing !== decl)
             nameError(decl.name, decl.position, existing)
@@ -116,7 +89,7 @@ internal class AstIdentifiersChecker(private val program: Program, private val e
             if (existing != null && existing !== subroutine)
                 nameError(subroutine.name, subroutine.position, existing)
 
-            // check that there are no local variables, labels, or other subs that redefine the subroutine's parameters
+            // check that there are no local variables, labels, or other subs that redefine the subroutine's parameters. Blocks are okay.
             val symbolsInSub = subroutine.allDefinedSymbols()
             val namesInSub = symbolsInSub.map{ it.first }.toSet()
             val paramNames = subroutine.parameters.map { it.name }.toSet()
@@ -128,9 +101,6 @@ internal class AstIdentifiersChecker(private val program: Program, private val e
                 val sub = subroutine.statements.firstOrNull { it is Subroutine && it.name==name}
                 if(sub!=null)
                     nameError(name, subroutine.position, sub)
-                val block = program.allBlocks().firstOrNull { it.name==name }
-                if(block!=null)
-                    nameError(name, subroutine.position, block)
             }
 
             if(subroutine.isAsmSubroutine && subroutine.statements.any{it !is InlineAssembly}) {
@@ -169,14 +139,4 @@ internal class AstIdentifiersChecker(private val program: Program, private val e
 
         super.visit(string)
     }
-
-    override fun visit(structDecl: StructDecl) {
-        for(member in structDecl.statements){
-            val decl = member as? VarDecl
-            if(decl!=null && decl.datatype !in NumericDatatypes)
-                errors.err("structs can only contain numerical types", decl.position)
-        }
-
-        super.visit(structDecl)
-    }
 }

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

@@ -3,33 +3,16 @@ package prog8.compiler.astprocessing
 import prog8.ast.Node
 import prog8.ast.Program
 import prog8.ast.base.DataType
+import prog8.ast.expressions.ArrayIndexedExpression
 import prog8.ast.expressions.BinaryExpression
+import prog8.ast.expressions.DirectMemoryRead
 import prog8.ast.expressions.StringLiteralValue
-import prog8.ast.statements.AnonymousScope
-import prog8.ast.statements.ParameterVarDecl
-import prog8.ast.statements.Subroutine
-import prog8.ast.statements.VarDecl
+import prog8.ast.statements.*
 import prog8.ast.walk.AstWalker
 import prog8.ast.walk.IAstModification
 
 
 internal class AstVariousTransforms(private val program: Program) : AstWalker() {
-    private val noModifications = emptyList<IAstModification>()
-
-    override fun before(decl: VarDecl, parent: Node): Iterable<IAstModification> {
-        // is it a struct variable? then define all its struct members as mangled names,
-        //    and include the original decl as well.
-        if(decl.datatype==DataType.STRUCT && !decl.structHasBeenFlattened) {
-            val decls = decl.flattenStructMembers()
-            decls.add(decl)
-            val result = AnonymousScope(decls, decl.position)
-            return listOf(IAstModification.ReplaceNode(
-                    decl, result, parent
-            ))
-        }
-
-        return noModifications
-    }
 
     override fun after(subroutine: Subroutine, parent: Node): Iterable<IAstModification> {
         // For non-kernal subroutines and non-asm parameters:
@@ -83,6 +66,10 @@ internal class AstVariousTransforms(private val program: Program) : AstWalker()
         return noModifications
     }
 
+    override fun after(arrayIndexedExpression: ArrayIndexedExpression, parent: Node): Iterable<IAstModification> {
+        return replacePointerVarIndexWithMemread(program, arrayIndexedExpression, parent)
+    }
+
     private fun concatString(expr: BinaryExpression): StringLiteralValue? {
         val rightStrval = expr.right as? StringLiteralValue
         val leftStrval = expr.left as? StringLiteralValue
@@ -109,3 +96,25 @@ internal class AstVariousTransforms(private val program: Program) : AstWalker()
         }
     }
 }
+
+
+
+internal fun replacePointerVarIndexWithMemread(program: Program, arrayIndexedExpression: ArrayIndexedExpression, parent: Node): Iterable<IAstModification> {
+    val arrayVar = arrayIndexedExpression.arrayvar.targetVarDecl(program)
+    if(arrayVar!=null && arrayVar.datatype ==  DataType.UWORD) {
+        // rewrite   pointervar[index]  into  @(pointervar+index)
+        val indexer = arrayIndexedExpression.indexer
+        val add = BinaryExpression(arrayIndexedExpression.arrayvar, "+", indexer.indexExpr, arrayIndexedExpression.position)
+        return if(parent is AssignTarget) {
+            // we're part of the target of an assignment, we have to actually change the assign target itself
+            val memwrite = DirectMemoryWrite(add, arrayIndexedExpression.position)
+            val newtarget = AssignTarget(null, null, memwrite, arrayIndexedExpression.position)
+            listOf(IAstModification.ReplaceNode(parent, newtarget, parent.parent))
+        } else {
+            val memread = DirectMemoryRead(add, arrayIndexedExpression.position)
+            listOf(IAstModification.ReplaceNode(arrayIndexedExpression, memread, parent))
+        }
+    }
+
+    return emptyList()
+}

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

@@ -13,7 +13,6 @@ import prog8.ast.walk.IAstModification
 
 
 internal class LiteralsToAutoVars(private val program: Program) : AstWalker() {
-    private val noModifications = emptyList<IAstModification>()
 
     override fun after(string: StringLiteralValue, parent: Node): Iterable<IAstModification> {
         if(string.parent !is VarDecl && string.parent !is WhenChoice) {
@@ -39,7 +38,7 @@ internal class LiteralsToAutoVars(private val program: Program) : AstWalker() {
             val arrayDt = array.guessDatatype(program)
             if(arrayDt.isKnown) {
                 // this array literal is part of an expression, turn it into an identifier reference
-                val litval2 = array.cast(arrayDt.typeOrElse(DataType.STRUCT))
+                val litval2 = array.cast(arrayDt.typeOrElse(DataType.UNDEFINED))
                 if(litval2!=null) {
                     val vardecl2 = VarDecl.createAuto(litval2)
                     val identifier = IdentifierReference(listOf(vardecl2.name), vardecl2.position)

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

@@ -1,7 +1,11 @@
 package prog8.compiler.astprocessing
 
-import prog8.ast.*
-import prog8.ast.base.*
+import prog8.ast.IFunctionCall
+import prog8.ast.Module
+import prog8.ast.Node
+import prog8.ast.Program
+import prog8.ast.base.DataType
+import prog8.ast.base.FatalAstException
 import prog8.ast.expressions.*
 import prog8.ast.statements.*
 import prog8.ast.walk.AstWalker
@@ -18,12 +22,10 @@ internal class StatementReorderer(val program: Program, val errors: IErrorReport
     // - in every block and module, most directives and vardecls are moved to the top. (not in subroutines!)
     // - the 'start' subroutine is moved to the top.
     // - (syntax desugaring) a vardecl with a non-const initializer value is split into a regular vardecl and an assignment statement.
-    // - (syntax desugaring) struct value assignment is expanded into several struct member assignments.
     // - in-place assignments are reordered a bit so that they are mostly of the form A = A <operator> <rest>
     // - sorts the choices in when statement.
     // - insert AddressOf (&) expression where required (string params to a UWORD function param etc).
 
-    private val noModifications = emptyList<IAstModification>()
     private val directivesToMove = setOf("%output", "%launcher", "%zeropage", "%zpreserved", "%address", "%option")
 
     override fun after(module: Module, parent: Node): Iterable<IAstModification> {
@@ -84,44 +86,17 @@ internal class StatementReorderer(val program: Program, val errors: IErrorReport
     }
 
     override fun after(arrayIndexedExpression: ArrayIndexedExpression, parent: Node): Iterable<IAstModification> {
-
-        val arrayVar = arrayIndexedExpression.arrayvar.targetVarDecl(program)
-        if(arrayVar!=null && arrayVar.datatype ==  DataType.UWORD) {
-            // rewrite   pointervar[index]  into  @(pointervar+index)
-            val indexer = arrayIndexedExpression.indexer
-            val index = (indexer.indexNum ?: indexer.indexVar)!!
-            val add = BinaryExpression(arrayIndexedExpression.arrayvar, "+", index, arrayIndexedExpression.position)
-            return if(parent is AssignTarget) {
-                // we're part of the target of an assignment, we have to actually change the assign target itself
-                val memwrite = DirectMemoryWrite(add, arrayIndexedExpression.position)
-                val newtarget = AssignTarget(null, null, memwrite, arrayIndexedExpression.position)
-                listOf(IAstModification.ReplaceNode(parent, newtarget, parent.parent))
-            } else {
-                val memread = DirectMemoryRead(add, arrayIndexedExpression.position)
-                listOf(IAstModification.ReplaceNode(arrayIndexedExpression, memread, parent))
-            }
-        }
-
-        when (val expr2 = arrayIndexedExpression.indexer.origExpression) {
-            is NumericLiteralValue -> {
-                arrayIndexedExpression.indexer.indexNum = expr2
-                arrayIndexedExpression.indexer.origExpression = null
-                return noModifications
-            }
-            is IdentifierReference -> {
-                arrayIndexedExpression.indexer.indexVar = expr2
-                arrayIndexedExpression.indexer.origExpression = null
-                return noModifications
-            }
-            is Expression -> {
-                // replace complex indexing with a temp variable
-                return getAutoIndexerVarFor(arrayIndexedExpression)
-            }
-            else -> return noModifications
-        }
+        return replacePointerVarIndexWithMemread(program, arrayIndexedExpression, parent)
     }
 
     override fun after(expr: BinaryExpression, parent: Node): Iterable<IAstModification> {
+
+        // ConstValue <associativeoperator> X -->  X <associativeoperator> ConstValue
+        // (this should be done by the ExpressionSimplifier when optimizing is enabled,
+        //  but the current assembly code generator for IF statements now also depends on it so we do it here regardless of optimization.)
+        if (expr.left.constValue(program) != null && expr.operator in associativeOperators && expr.right.constValue(program) == null)
+            return listOf(IAstModification.SwapOperands(expr))
+
         // when using a simple bit shift and assigning it to a variable of a different type,
         // try to make the bit shifting 'wide enough' to fall into the variable's type.
         // with this, for instance, uword x = 1 << 10  will result in 1024 rather than 0 (the ubyte result).
@@ -131,7 +106,7 @@ internal class StatementReorderer(val program: Program, val errors: IErrorReport
                 is Assignment -> {
                     val targetDt = parent.target.inferType(program)
                     if(leftDt != targetDt) {
-                        val cast = TypecastExpression(expr.left, targetDt.typeOrElse(DataType.STRUCT), true, parent.position)
+                        val cast = TypecastExpression(expr.left, targetDt.typeOrElse(DataType.UNDEFINED), true, parent.position)
                         return listOf(IAstModification.ReplaceNode(expr.left, cast, expr))
                     }
                 }
@@ -202,38 +177,6 @@ internal class StatementReorderer(val program: Program, val errors: IErrorReport
         return noModifications
     }
 
-    private fun getAutoIndexerVarFor(expr: ArrayIndexedExpression): MutableList<IAstModification> {
-        val modifications = mutableListOf<IAstModification>()
-        val subroutine = expr.definingSubroutine()!!
-        val statement = expr.containingStatement()
-        val indexerVarPrefix = "prog8_autovar_index_"
-        val repo = subroutine.asmGenInfo.usedAutoArrayIndexerForStatements
-
-        // TODO make this a bit smarter so it can reuse indexer variables. BUT BEWARE of scoping+initialization problems then
-        // add another loop index var to be used for this expression
-        val indexerVarName = "$indexerVarPrefix${expr.indexer.hashCode()}"
-        val indexerVar = AsmGenInfo.ArrayIndexerInfo(indexerVarName, expr.indexer)
-        repo.add(indexerVar)
-        // create the indexer var at block level scope
-        val vardecl = VarDecl(VarDeclType.VAR, DataType.UBYTE, ZeropageWish.PREFER_ZEROPAGE,
-                null, indexerVarName, null, null, isArray = false, autogeneratedDontRemove = true, position = expr.position)
-        modifications.add(IAstModification.InsertFirst(vardecl, subroutine))
-
-        // replace the indexer with just the variable
-        // assign the indexing expression to the helper variable, but only if that hasn't been done already
-        val indexerExpression = expr.indexer.origExpression!!
-        val target = AssignTarget(IdentifierReference(listOf(indexerVar.name), indexerExpression.position), null, null, indexerExpression.position)
-        val assign = Assignment(target, indexerExpression, indexerExpression.position)
-        modifications.add(IAstModification.InsertBefore(statement, assign, statement.definingScope()))
-        modifications.add(IAstModification.SetExpression( {
-            expr.indexer.indexVar = it as IdentifierReference
-            expr.indexer.indexNum = null
-            expr.indexer.origExpression = null
-        }, target.identifier!!.copy(), expr.indexer))
-
-        return modifications
-    }
-
     override fun after(whenStatement: WhenStatement, parent: Node): Iterable<IAstModification> {
         val choices = whenStatement.choiceValues(program).sortedBy {
             it.first?.first() ?: Int.MAX_VALUE
@@ -243,57 +186,18 @@ internal class StatementReorderer(val program: Program, val errors: IErrorReport
         return noModifications
     }
 
-    override fun after(decl: VarDecl, parent: Node): Iterable<IAstModification> {
-        val declValue = decl.value
-        if(declValue!=null && decl.type== VarDeclType.VAR && decl.datatype in NumericDatatypes) {
-            val declConstValue = declValue.constValue(program)
-            if(declConstValue==null) {
-                // move the vardecl (without value) to the scope and replace this with a regular assignment
-                // Unless we're dealing with a floating point variable because that will actually make things less efficient at the moment (because floats are mostly calcualated via the stack)
-                if(decl.datatype!=DataType.FLOAT) {
-                    decl.value = null
-                    decl.allowInitializeWithZero = false
-                    val target = AssignTarget(IdentifierReference(listOf(decl.name), decl.position), null, null, decl.position)
-                    val assign = Assignment(target, declValue, decl.position)
-                    return listOf(
-                            IAstModification.ReplaceNode(decl, assign, parent),
-                            IAstModification.InsertFirst(decl, decl.definingScope())
-                    )
-                }
-            }
-        }
-        return noModifications
-    }
-
     override fun before(assignment: Assignment, parent: Node): Iterable<IAstModification> {
         val valueType = assignment.value.inferType(program)
         val targetType = assignment.target.inferType(program)
-        var assignments = emptyList<Assignment>()
 
-        if(targetType.istype(DataType.STRUCT) && (valueType.istype(DataType.STRUCT) || valueType.typeOrElse(DataType.STRUCT) in ArrayDatatypes )) {
-            assignments = if (assignment.value is ArrayLiteralValue) {
-                flattenStructAssignmentFromStructLiteral(assignment)    //  'structvar = [ ..... ] '
+        if(targetType.isArray() && valueType.isArray() ) {
+            if (assignment.value is ArrayLiteralValue) {
+                errors.err("cannot assign array literal here, use separate assignment per element", assignment.position)
             } else {
-                flattenStructAssignmentFromIdentifier(assignment)    //   'structvar1 = structvar2'
+                return copyArrayValue(assignment)
             }
         }
 
-        if(targetType.typeOrElse(DataType.STRUCT) in ArrayDatatypes && valueType.typeOrElse(DataType.STRUCT) in ArrayDatatypes ) {
-            assignments = if (assignment.value is ArrayLiteralValue) {
-                flattenArrayAssignmentFromArrayLiteral(assignment)    //  'arrayvar = [ ..... ] '
-            } else {
-                flattenArrayAssignmentFromIdentifier(assignment)    //   'arrayvar1 = arrayvar2'
-            }
-        }
-
-        if(assignments.isNotEmpty()) {
-            val modifications = mutableListOf<IAstModification>()
-            val scope = assignment.definingScope()
-            assignments.reversed().mapTo(modifications) { IAstModification.InsertAfter(assignment, it, scope) }
-            modifications.add(IAstModification.Remove(assignment, scope))
-            return modifications
-        }
-
         return noModifications
     }
 
@@ -346,125 +250,40 @@ internal class StatementReorderer(val program: Program, val errors: IErrorReport
         return noModifications
     }
 
-    private fun flattenArrayAssignmentFromArrayLiteral(assign: Assignment): List<Assignment> {
+    private fun copyArrayValue(assign: Assignment): List<IAstModification> {
         val identifier = assign.target.identifier!!
         val targetVar = identifier.targetVarDecl(program)!!
-        val alv = assign.value as? ArrayLiteralValue
-        return flattenArrayAssign(targetVar, alv, identifier, assign.position)
-    }
 
-    private fun flattenArrayAssignmentFromIdentifier(assign: Assignment): List<Assignment> {
-        val identifier = assign.target.identifier!!
-        val targetVar = identifier.targetVarDecl(program)!!
+        if(targetVar.arraysize==null)
+            errors.err("array has no defined size", assign.position)
+
+        if(assign.value !is IdentifierReference) {
+            errors.err("invalid array value to assign to other array", assign.value.position)
+            return noModifications
+        }
         val sourceIdent = assign.value as IdentifierReference
         val sourceVar = sourceIdent.targetVarDecl(program)!!
         if(!sourceVar.isArray) {
-            errors.err("value must be an array",  sourceIdent.position)
-            return emptyList()
+            errors.err("value must be an array", sourceIdent.position)
+        } else {
+            if (sourceVar.arraysize!!.constIndex() != targetVar.arraysize!!.constIndex())
+                errors.err("element count mismatch", assign.position)
+            if (sourceVar.datatype != targetVar.datatype)
+                errors.err("element type mismatch", assign.position)
         }
-        val alv = sourceVar.value as? ArrayLiteralValue
-        return flattenArrayAssign(targetVar, alv, identifier, assign.position)
+
+        if(!errors.noErrors())
+            return noModifications
+
+        val memcopy = FunctionCallStatement(IdentifierReference(listOf("sys", "memcopy"), assign.position),
+            mutableListOf(
+                AddressOf(sourceIdent, assign.position),
+                AddressOf(identifier, assign.position),
+                NumericLiteralValue.optimalInteger(targetVar.arraysize!!.constIndex()!!, assign.position)
+            ),
+            true,
+            assign.position
+        )
+        return listOf(IAstModification.ReplaceNode(assign, memcopy, assign.parent))
     }
-
-    private fun flattenArrayAssign(targetVar: VarDecl, alv: ArrayLiteralValue?, identifier: IdentifierReference, position: Position): List<Assignment> {
-        if(targetVar.arraysize==null) {
-            errors.err("array has no defined size", identifier.position)
-            return emptyList()
-        }
-
-        if(alv==null || alv.value.size != targetVar.arraysize!!.constIndex()) {
-            errors.err("element count mismatch", position)
-            return emptyList()
-        }
-
-        // TODO use memcopy instead of individual assignments after certain amount of elements
-        // TODO what does assigning a struct var use?
-        return alv.value.mapIndexed { index, value ->
-            val idx = ArrayIndexedExpression(identifier, ArrayIndex(NumericLiteralValue(DataType.UBYTE, index, position), position), position)
-            Assignment(AssignTarget(null, idx, null, position), value, value.position)
-        }
-    }
-
-    private fun flattenStructAssignmentFromStructLiteral(structAssignment: Assignment): List<Assignment> {
-        val identifier = structAssignment.target.identifier!!
-        val identifierName = identifier.nameInSource.single()
-        val targetVar = identifier.targetVarDecl(program)!!
-        val struct = targetVar.struct!!
-
-        val slv = structAssignment.value as? ArrayLiteralValue
-        if(slv==null || slv.value.size != struct.numberOfElements) {
-            errors.err("element count mismatch", structAssignment.position)
-            return emptyList()
-        }
-
-        return struct.statements.zip(slv.value).map { (targetDecl, sourceValue) ->
-            targetDecl as VarDecl
-            val mangled = mangledStructMemberName(identifierName, targetDecl.name)
-            val idref = IdentifierReference(listOf(mangled), structAssignment.position)
-            val assign = Assignment(AssignTarget(idref, null, null, structAssignment.position),
-                    sourceValue, sourceValue.position)
-            assign.linkParents(structAssignment)
-            assign
-        }
-    }
-
-    private fun flattenStructAssignmentFromIdentifier(structAssignment: Assignment): List<Assignment> {
-        // TODO use memcopy beyond a certain number of elements
-        val identifier = structAssignment.target.identifier!!
-        val identifierName = identifier.nameInSource.single()
-        val targetVar = identifier.targetVarDecl(program)!!
-        val struct = targetVar.struct!!
-        when (structAssignment.value) {
-            is IdentifierReference -> {
-                val sourceVar = (structAssignment.value as IdentifierReference).targetVarDecl(program)!!
-                when {
-                    sourceVar.struct!=null -> {
-                        // struct memberwise copy
-                        val sourceStruct = sourceVar.struct!!
-                        if(sourceStruct!==targetVar.struct) {
-                            // structs are not the same in assignment
-                            return listOf()     // error will be printed elsewhere
-                        }
-                        if(struct.statements.size!=sourceStruct.statements.size)
-                            return listOf()     // error will be printed elsewhere
-                        return struct.statements.zip(sourceStruct.statements).map { member ->
-                            val targetDecl = member.first as VarDecl
-                            val sourceDecl = member.second as VarDecl
-                            if(targetDecl.name != sourceDecl.name)
-                                throw FatalAstException("struct member mismatch")
-                            val mangled = mangledStructMemberName(identifierName, targetDecl.name)
-                            val idref = IdentifierReference(listOf(mangled), structAssignment.position)
-                            val sourcemangled = mangledStructMemberName(sourceVar.name, sourceDecl.name)
-                            val sourceIdref = IdentifierReference(listOf(sourcemangled), structAssignment.position)
-                            val assign = Assignment(AssignTarget(idref, null, null, structAssignment.position), sourceIdref, member.second.position)
-                            assign.linkParents(structAssignment)
-                            assign
-                        }
-                    }
-                    sourceVar.isArray -> {
-                        val array = (sourceVar.value as ArrayLiteralValue).value
-                        if(struct.statements.size!=array.size)
-                            return listOf()     // error will be printed elsewhere
-                        return struct.statements.zip(array).map {
-                            val decl = it.first as VarDecl
-                            val mangled = mangledStructMemberName(identifierName, decl.name)
-                            val targetName = IdentifierReference(listOf(mangled), structAssignment.position)
-                            val target = AssignTarget(targetName, null, null, structAssignment.position)
-                            val assign = Assignment(target, it.second, structAssignment.position)
-                            assign.linkParents(structAssignment)
-                            assign
-                        }
-                    }
-                    else -> {
-                        throw FatalAstException("can only assign arrays or structs to structs")
-                    }
-                }
-            }
-            is ArrayLiteralValue -> {
-                throw IllegalArgumentException("not going to flatten a structLv assignment here")
-            }
-            else -> throw FatalAstException("strange struct value")
-        }
-    }
-
 }

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

@@ -18,16 +18,18 @@ class TypecastsAdder(val program: Program, val errors: IErrorReporter) : AstWalk
      * (this includes function call arguments)
      */
 
-    private val noModifications = emptyList<IAstModification>()
-
     override fun after(decl: VarDecl, parent: Node): Iterable<IAstModification> {
         val declValue = decl.value
-        if(decl.type==VarDeclType.VAR && declValue!=null && decl.struct==null) {
+        if(decl.type==VarDeclType.VAR && declValue!=null) {
             val valueDt = declValue.inferType(program)
             if(!valueDt.istype(decl.datatype)) {
 
                 // don't add a typecast on an array initializer value
-                if(valueDt.typeOrElse(DataType.STRUCT) in IntegerDatatypes && decl.datatype in ArrayDatatypes)
+                if(valueDt.isInteger() && decl.datatype in ArrayDatatypes)
+                    return noModifications
+
+                // don't add a typecast if the initializer value is inherently not assignable
+                if(valueDt isNotAssignableTo decl.datatype)
                     return noModifications
 
                 return listOf(IAstModification.ReplaceNode(
@@ -45,7 +47,7 @@ class TypecastsAdder(val program: Program, val errors: IErrorReporter) : AstWalk
         val rightDt = expr.right.inferType(program)
         if(leftDt.isKnown && rightDt.isKnown && leftDt!=rightDt) {
             // determine common datatype and add typecast as required to make left and right equal types
-            val (commonDt, toFix) = BinaryExpression.commonDatatype(leftDt.typeOrElse(DataType.STRUCT), rightDt.typeOrElse(DataType.STRUCT), expr.left, expr.right)
+            val (commonDt, toFix) = BinaryExpression.commonDatatype(leftDt.typeOrElse(DataType.UNDEFINED), rightDt.typeOrElse(DataType.UNDEFINED), expr.left, expr.right)
             if(toFix!=null) {
                 return when {
                     toFix===expr.left -> listOf(IAstModification.ReplaceNode(
@@ -64,8 +66,8 @@ class TypecastsAdder(val program: Program, val errors: IErrorReporter) : AstWalk
         val valueItype = assignment.value.inferType(program)
         val targetItype = assignment.target.inferType(program)
         if(targetItype.isKnown && valueItype.isKnown) {
-            val targettype = targetItype.typeOrElse(DataType.STRUCT)
-            val valuetype = valueItype.typeOrElse(DataType.STRUCT)
+            val targettype = targetItype.typeOrElse(DataType.UNDEFINED)
+            val valuetype = valueItype.typeOrElse(DataType.UNDEFINED)
             if (valuetype != targettype) {
                 if (valuetype isAssignableTo targettype) {
                     if(valuetype in IterableDatatypes && targettype==DataType.UWORD)
@@ -124,7 +126,7 @@ class TypecastsAdder(val program: Program, val errors: IErrorReporter) : AstWalk
                 sub.parameters.zip(call.args).forEachIndexed { index, pair ->
                     val argItype = pair.second.inferType(program)
                     if(argItype.isKnown) {
-                        val argtype = argItype.typeOrElse(DataType.STRUCT)
+                        val argtype = argItype.typeOrElse(DataType.UNDEFINED)
                         val requiredType = pair.first.type
                         if (requiredType != argtype) {
                             if (argtype isAssignableTo requiredType) {
@@ -157,7 +159,7 @@ class TypecastsAdder(val program: Program, val errors: IErrorReporter) : AstWalk
                 func.parameters.zip(call.args).forEachIndexed { index, pair ->
                     val argItype = pair.second.inferType(program)
                     if (argItype.isKnown) {
-                        val argtype = argItype.typeOrElse(DataType.STRUCT)
+                        val argtype = argItype.typeOrElse(DataType.UNDEFINED)
                         if (pair.first.possibleDatatypes.all { argtype != it }) {
                             for (possibleType in pair.first.possibleDatatypes) {
                                 if (argtype isAssignableTo possibleType) {

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

@@ -3,18 +3,17 @@ package prog8.compiler.astprocessing
 import prog8.ast.IFunctionCall
 import prog8.ast.INameScope
 import prog8.ast.Node
+import prog8.ast.Program
+import prog8.ast.base.FatalAstException
 import prog8.ast.base.Position
-import prog8.ast.expressions.DirectMemoryRead
-import prog8.ast.expressions.FunctionCall
-import prog8.ast.expressions.NumericLiteralValue
-import prog8.ast.expressions.TypecastExpression
+import prog8.ast.expressions.*
 import prog8.ast.statements.*
 import prog8.ast.walk.AstWalker
 import prog8.ast.walk.IAstModification
+import prog8.compiler.IErrorReporter
 
 
-internal class VariousCleanups: AstWalker() {
-    private val noModifications = emptyList<IAstModification>()
+internal class VariousCleanups(val program: Program, val errors: IErrorReporter): AstWalker() {
 
     override fun before(nopStatement: NopStatement, parent: Node): Iterable<IAstModification> {
         return listOf(IAstModification.Remove(nopStatement, parent as INameScope))
@@ -32,21 +31,12 @@ internal class VariousCleanups: AstWalker() {
             val idx = into.statements.indexOf(scope)
             if(idx>=0) {
                 into.statements.addAll(idx+1, scope.statements)
+                scope.statements.forEach { it.parent = into as Node }
                 into.statements.remove(scope)
             }
         }
     }
 
-    override fun before(typecast: TypecastExpression, parent: Node): Iterable<IAstModification> {
-        if(typecast.expression is NumericLiteralValue) {
-            val value = (typecast.expression as NumericLiteralValue).cast(typecast.type)
-            if(value.isValid)
-                return listOf(IAstModification.ReplaceNode(typecast, value.valueOrZero(), parent))
-        }
-
-        return noModifications
-    }
-
     override fun before(functionCallStatement: FunctionCallStatement, parent: Node): Iterable<IAstModification> {
         return before(functionCallStatement as IFunctionCall, parent, functionCallStatement.position)
     }
@@ -70,4 +60,62 @@ internal class VariousCleanups: AstWalker() {
         return noModifications
     }
 
+    override fun after(typecast: TypecastExpression, parent: Node): Iterable<IAstModification> {
+        if(typecast.parent!==parent)
+            throw FatalAstException("parent node mismatch at $typecast")
+
+        if(typecast.expression is NumericLiteralValue) {
+            val value = (typecast.expression as NumericLiteralValue).cast(typecast.type)
+            if(value.isValid)
+                return listOf(IAstModification.ReplaceNode(typecast, value.valueOrZero(), parent))
+        }
+
+        val sourceDt = typecast.expression.inferType(program)
+        if(sourceDt.istype(typecast.type))
+            return listOf(IAstModification.ReplaceNode(typecast, typecast.expression, parent))
+
+        return noModifications
+    }
+
+    override fun after(subroutine: Subroutine, parent: Node): Iterable<IAstModification> {
+        if(subroutine.parent!==parent)
+            throw FatalAstException("parent node mismatch at $subroutine")
+        return noModifications
+    }
+
+    override fun after(assignment: Assignment, parent: Node): Iterable<IAstModification> {
+        if(assignment.parent!==parent)
+            throw FatalAstException("parent node mismatch at $assignment")
+        return noModifications
+    }
+
+    override fun after(assignTarget: AssignTarget, parent: Node): Iterable<IAstModification> {
+        if(assignTarget.parent!==parent)
+            throw FatalAstException("parent node mismatch at $assignTarget")
+        return noModifications
+    }
+
+    override fun after(decl: VarDecl, parent: Node): Iterable<IAstModification> {
+        if(decl.parent!==parent)
+            throw FatalAstException("parent node mismatch at $decl")
+        return noModifications
+    }
+
+    override fun after(scope: AnonymousScope, parent: Node): Iterable<IAstModification> {
+        if(scope.parent!==parent)
+            throw FatalAstException("parent node mismatch at $scope")
+        return noModifications
+    }
+
+    override fun after(returnStmt: Return, parent: Node): Iterable<IAstModification> {
+        if(returnStmt.parent!==parent)
+            throw FatalAstException("parent node mismatch at $returnStmt")
+        return noModifications
+    }
+
+    override fun after(identifier: IdentifierReference, parent: Node): Iterable<IAstModification> {
+        if(identifier.parent!==parent)
+            throw FatalAstException("parent node mismatch at $identifier")
+        return noModifications
+    }
 }

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

@@ -44,7 +44,7 @@ class VerifyFunctionArgTypes(val program: Program) : IAstVisitor {
             val firstUnknownDt = argITypes.indexOfFirst { it.isUnknown }
             if(firstUnknownDt>=0)
                 return "argument ${firstUnknownDt+1} invalid argument type"
-            val argtypes = argITypes.map { it.typeOrElse(DataType.STRUCT) }
+            val argtypes = argITypes.map { it.typeOrElse(DataType.UNDEFINED) }
             val target = call.target.targetStatement(program)
             if (target is Subroutine) {
                 if(call.args.size != target.parameters.size)

compiler/src/prog8/compiler/functions/BuiltinFunctions.kt

@@ -4,7 +4,6 @@ import prog8.ast.IMemSizer
 import prog8.ast.Program
 import prog8.ast.base.*
 import prog8.ast.expressions.*
-import prog8.ast.statements.StructDecl
 import prog8.ast.statements.VarDecl
 import prog8.compiler.CompilerException
 import kotlin.math.*
@@ -97,6 +96,7 @@ private val functionSignatures: List<FSignature> = listOf(
     FSignature("ror2"        , false, listOf(FParam("item", setOf(DataType.UBYTE, DataType.UWORD))), null),
     FSignature("sort"        , false, listOf(FParam("array", ArrayDatatypes)), null),
     FSignature("reverse"     , false, listOf(FParam("array", ArrayDatatypes)), null),
+    FSignature("cmp"         , false, listOf(FParam("value1", IntegerDatatypes), FParam("value2", NumericDatatypes)), null),
         // these few have a return value depending on the argument(s):
     FSignature("max"         , true, listOf(FParam("values", ArrayDatatypes)), null) { a, p, prg, ct -> collectionArg(a, p, prg, ::builtinMax) },    // type depends on args
     FSignature("min"         , true, listOf(FParam("values", ArrayDatatypes)), null) { a, p, prg, ct -> collectionArg(a, p, prg, ::builtinMin) },    // type depends on args
@@ -104,7 +104,6 @@ private val functionSignatures: List<FSignature> = listOf(
     FSignature("abs"         , true, listOf(FParam("value", NumericDatatypes)), null, ::builtinAbs),      // type depends on argument
     FSignature("len"         , true, listOf(FParam("values", IterableDatatypes)), null, ::builtinLen),    // type is UBYTE or UWORD depending on actual length
     FSignature("sizeof"      , true, listOf(FParam("object", DataType.values().toSet())), DataType.UBYTE, ::builtinSizeof),
-    FSignature("offsetof"    , true, listOf(FParam("object", DataType.values().toSet())), DataType.UBYTE, ::builtinOffsetof),
         // normal functions follow:
     FSignature("sgn"         , true, listOf(FParam("value", NumericDatatypes)), DataType.BYTE, ::builtinSgn ),
     FSignature("sin"         , true, listOf(FParam("rads", setOf(DataType.FLOAT))), DataType.FLOAT) { a, p, prg, ct -> oneDoubleArg(a, p, prg, Math::sin) },
@@ -142,6 +141,8 @@ private val functionSignatures: List<FSignature> = listOf(
     FSignature("rndf"        , false, emptyList(), DataType.FLOAT),
     FSignature("memory"      , true, listOf(FParam("name", setOf(DataType.STR)), FParam("size", setOf(DataType.UWORD))), DataType.UWORD),
     FSignature("swap"        , false, listOf(FParam("first", NumericDatatypes), FParam("second", NumericDatatypes)), null),
+    FSignature("callfar"     , false, listOf(FParam("bank", setOf(DataType.UBYTE)), FParam("address", setOf(DataType.UWORD)), FParam("arg", setOf(DataType.UWORD))), null),
+    FSignature("callrom"     , false, listOf(FParam("bank", setOf(DataType.UBYTE)), FParam("address", setOf(DataType.UWORD)), FParam("arg", setOf(DataType.UWORD))), null),
 
 )
 
@@ -152,7 +153,7 @@ fun builtinMax(array: List<Number>): Number = array.maxByOrNull { it.toDouble()
 
 fun builtinMin(array: List<Number>): Number = array.minByOrNull { it.toDouble() }!!
 
-fun builtinSum(array: List<Number>): Number = array.sumByDouble { it.toDouble() }
+fun builtinSum(array: List<Number>): Number = array.sumOf { it.toDouble() }
 
 fun builtinAny(array: List<Number>): Number = if(array.any { it.toDouble()!=0.0 }) 1 else 0
 
@@ -163,7 +164,7 @@ fun builtinFunctionReturnType(function: String, args: List<Expression>, program:
 
     fun datatypeFromIterableArg(arglist: Expression): DataType {
         if(arglist is ArrayLiteralValue) {
-            val dt = arglist.value.map {it.inferType(program).typeOrElse(DataType.STRUCT)}.toSet()
+            val dt = arglist.value.map {it.inferType(program).typeOrElse(DataType.UNDEFINED)}.toSet()
             if(dt.any { it !in NumericDatatypes }) {
                 throw FatalAstException("fuction $function only accepts array of numeric values")
             }
@@ -177,9 +178,9 @@ fun builtinFunctionReturnType(function: String, args: List<Expression>, program:
             val idt = arglist.inferType(program)
             if(!idt.isKnown)
                 throw FatalAstException("couldn't determine type of iterable $arglist")
-            return when(val dt = idt.typeOrElse(DataType.STRUCT)) {
+            return when(val dt = idt.typeOrElse(DataType.UNDEFINED)) {
                 DataType.STR, in NumericDatatypes -> dt
-                in ArrayDatatypes -> ArrayElementTypes.getValue(dt)
+                in ArrayDatatypes -> ArrayToElementTypes.getValue(dt)
                 else -> throw FatalAstException("function '$function' requires one argument which is an iterable")
             }
         }
@@ -194,7 +195,7 @@ fun builtinFunctionReturnType(function: String, args: List<Expression>, program:
     return when (function) {
         "abs" -> {
             val dt = args.single().inferType(program)
-            return if(dt.typeOrElse(DataType.STRUCT) in NumericDatatypes)
+            return if(dt.isNumeric())
                 dt
             else
                 InferredTypes.InferredType.unknown()
@@ -203,7 +204,7 @@ fun builtinFunctionReturnType(function: String, args: List<Expression>, program:
             when(val dt = datatypeFromIterableArg(args.single())) {
                 DataType.STR -> InferredTypes.knownFor(DataType.UBYTE)
                 in NumericDatatypes -> InferredTypes.knownFor(dt)
-                in ArrayDatatypes -> InferredTypes.knownFor(ArrayElementTypes.getValue(dt))
+                in ArrayDatatypes -> InferredTypes.knownFor(ArrayToElementTypes.getValue(dt))
                 else -> InferredTypes.unknown()
             }
         }
@@ -286,28 +287,6 @@ private fun builtinAbs(args: List<Expression>, position: Position, program: Prog
     }
 }
 
-private fun builtinOffsetof(args: List<Expression>, position: Position, program: Program, memsizer: IMemSizer): NumericLiteralValue {
-    // 1 arg, type = anything, result type = ubyte
-    if(args.size!=1)
-        throw SyntaxError("offsetof requires one argument", position)
-    val idref = args[0] as? IdentifierReference
-        ?: throw SyntaxError("offsetof argument should be an identifier", position)
-
-    val vardecl = idref.targetVarDecl(program)!!
-    val struct = vardecl.struct
-    if (struct == null || vardecl.datatype == DataType.STRUCT)
-        throw SyntaxError("offsetof can only be used on struct members", position)
-
-    val membername = idref.nameInSource.last()
-    var offset = 0
-    for(member in struct.statements) {
-        if((member as VarDecl).name == membername)
-            return NumericLiteralValue(DataType.UBYTE, offset, position)
-        offset += memsizer.memorySize(member.datatype)
-    }
-    throw SyntaxError("undefined struct member", position)
-}
-
 private fun builtinSizeof(args: List<Expression>, position: Position, program: Program, memsizer: IMemSizer): NumericLiteralValue {
     // 1 arg, type = anything, result type = ubyte
     if(args.size!=1)
@@ -320,24 +299,14 @@ private fun builtinSizeof(args: List<Expression>, position: Position, program: P
         val target = (args[0] as IdentifierReference).targetStatement(program)
                 ?: throw CannotEvaluateException("sizeof", "no target")
 
-        fun structSize(target: StructDecl) =
-                NumericLiteralValue(DataType.UBYTE, target.statements.map { memsizer.memorySize((it as VarDecl).datatype) }.sum(), position)
-
         return when {
-            dt.typeOrElse(DataType.STRUCT) in ArrayDatatypes -> {
+            dt.isArray() -> {
                 val length = (target as VarDecl).arraysize!!.constIndex() ?: throw CannotEvaluateException("sizeof", "unknown array size")
-                val elementDt = ArrayElementTypes.getValue(dt.typeOrElse(DataType.STRUCT))
+                val elementDt = ArrayToElementTypes.getValue(dt.typeOrElse(DataType.UNDEFINED))
                 numericLiteral(memsizer.memorySize(elementDt) * length, position)
             }
-            dt.istype(DataType.STRUCT) -> {
-                when (target) {
-                    is VarDecl -> structSize(target.struct!!)
-                    is StructDecl -> structSize(target)
-                    else -> throw CompilerException("weird struct type $target")
-                }
-            }
             dt.istype(DataType.STR) -> throw SyntaxError("sizeof str is undefined, did you mean len?", position)
-            else -> NumericLiteralValue(DataType.UBYTE, memsizer.memorySize(dt.typeOrElse(DataType.STRUCT)), position)
+            else -> NumericLiteralValue(DataType.UBYTE, memsizer.memorySize(dt.typeOrElse(DataType.UNDEFINED)), position)
         }
     } else {
         throw SyntaxError("sizeof invalid argument type", position)
@@ -372,7 +341,6 @@ private fun builtinLen(args: List<Expression>, position: Position, program: Prog
             val refLv = target.value as? StringLiteralValue ?: throw CannotEvaluateException("len", "stringsize unknown")
             NumericLiteralValue.optimalInteger(refLv.value.length, args[0].position)
         }
-        DataType.STRUCT -> throw SyntaxError("cannot use len on struct, did you mean sizeof?", args[0].position)
         in NumericDatatypes -> throw SyntaxError("cannot use len on numeric value, did you mean sizeof?", args[0].position)
         else -> throw CompilerException("weird datatype")
     }

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

@@ -11,9 +11,10 @@ import prog8.compiler.CompilationOptions
 import prog8.compiler.IErrorReporter
 import prog8.compiler.Zeropage
 import prog8.compiler.target.c64.C64MachineDefinition
-import prog8.compiler.target.c64.Petscii
-import prog8.compiler.target.c64.codegen.AsmGen
+import prog8.compiler.target.cbm.Petscii
+import prog8.compiler.target.cpu6502.codegen.AsmGen
 import prog8.compiler.target.cx16.CX16MachineDefinition
+import java.io.CharConversionException
 import java.nio.file.Path
 
 
@@ -70,9 +71,17 @@ internal object C64Target: ICompilationTarget {
     override val name = "c64"
     override val machine = C64MachineDefinition
     override fun encodeString(str: String, altEncoding: Boolean) =
-            if(altEncoding) Petscii.encodeScreencode(str, true) else Petscii.encodePetscii(str, true)
+        try {
+            if (altEncoding) Petscii.encodeScreencode(str, true) else Petscii.encodePetscii(str, true)
+        } catch (x: CharConversionException) {
+            throw CharConversionException("can't convert string to target machine's char encoding: ${x.message}")
+        }
     override fun decodeString(bytes: List<Short>, altEncoding: Boolean) =
-            if(altEncoding) Petscii.decodeScreencode(bytes, true) else Petscii.decodePetscii(bytes, true)
+        try {
+            if (altEncoding) Petscii.decodeScreencode(bytes, true) else Petscii.decodePetscii(bytes, true)
+        } catch (x: CharConversionException) {
+            throw CharConversionException("can't decode string: ${x.message}")
+        }
 
     override fun memorySize(dt: DataType): Int {
         return when(dt) {
@@ -89,9 +98,17 @@ internal object Cx16Target: ICompilationTarget {
     override val name = "cx16"
     override val machine = CX16MachineDefinition
     override fun encodeString(str: String, altEncoding: Boolean) =
-            if(altEncoding) Petscii.encodeScreencode(str, true) else Petscii.encodePetscii(str, true)
+        try {
+            if (altEncoding) Petscii.encodeScreencode(str, true) else Petscii.encodePetscii(str, true)
+        } catch (x: CharConversionException) {
+            throw CharConversionException("can't convert string to target machine's char encoding: ${x.message}")
+        }
     override fun decodeString(bytes: List<Short>, altEncoding: Boolean) =
-            if(altEncoding) Petscii.decodeScreencode(bytes, true) else Petscii.decodePetscii(bytes, true)
+        try {
+            if (altEncoding) Petscii.decodeScreencode(bytes, true) else Petscii.decodePetscii(bytes, true)
+        } catch (x: CharConversionException) {
+            throw CharConversionException("can't decode string: ${x.message}")
+        }
 
     override fun memorySize(dt: DataType): Int {
         return when(dt) {
@@ -114,5 +131,6 @@ internal fun asmGeneratorFor(
     outputDir: Path
 ): IAssemblyGenerator
 {
+    // at the moment we only have one code generation backend (for 6502 and 65c02)
     return AsmGen(program, errors, zp, options, compTarget, outputDir)
 }

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

@@ -39,7 +39,7 @@ internal object C64MachineDefinition: IMachineDefinition {
         for(emulator in listOf("x64sc", "x64")) {
             println("\nStarting C-64 emulator $emulator...")
             val cmdline = listOf(emulator, "-silent", "-moncommands", "$programName.vice-mon-list",
-                    "-autostartprgmode", "1", "-autostart-warp", "-autostart", programName + ".prg")
+                    "-autostartprgmode", "1", "-autostart-warp", "-autostart", "$programName.prg")
             val processb = ProcessBuilder(cmdline).inheritIO()
             val process: Process
             try {
@@ -109,6 +109,7 @@ internal object C64MachineDefinition: IMachineDefinition {
                 if (options.zeropage == ZeropageType.FLOATSAFE) {
                     // remove the zero page locations used for floating point operations from the free list
                     free.removeAll(listOf(
+                            0x22, 0x23, 0x24, 0x25,
                             0x10, 0x11, 0x12, 0x26, 0x27, 0x28, 0x29, 0x2a,
                             0x57, 0x58, 0x59, 0x5a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f, 0x60,
                             0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68,

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

@@ -1,4 +1,4 @@
-package prog8.compiler.target.c64
+package prog8.compiler.target.cbm
 
 import prog8.compiler.CompilationOptions
 import prog8.compiler.OutputType

compiler/src/prog8/compiler/target/cbm/Petscii.kt

@@ -1,5 +1,6 @@
-package prog8.compiler.target.c64
+package prog8.compiler.target.cbm
 
+import prog8.ast.antlr.escape
 import java.io.CharConversionException
 
 object Petscii {
@@ -172,7 +173,7 @@ object Petscii {
             '\u258c',    //  ▌    0xA1 -> LEFT HALF BLOCK
             '\u2584',    //  ▄    0xA2 -> LOWER HALF BLOCK
             '\u2594',    //  ▔    0xA3 -> UPPER ONE EIGHTH BLOCK
-            '_',         //  ▁    0xA4 -> LOWER ONE EIGHTH BLOCK
+            '\u2581',    //  ▁    0xA4 -> LOWER ONE EIGHTH BLOCK
             '\u258f',    //  ▏    0xA5 -> LEFT ONE EIGHTH BLOCK
             '\u2592',    //  ▒    0xA6 -> MEDIUM SHADE
             '\u2595',    //  ▕    0xA7 -> RIGHT ONE EIGHTH BLOCK
@@ -236,7 +237,7 @@ object Petscii {
             '\u258c',    //  ▌    0xE1 -> LEFT HALF BLOCK
             '\u2584',    //  ▄    0xE2 -> LOWER HALF BLOCK
             '\u2594',    //  ▔    0xE3 -> UPPER ONE EIGHTH BLOCK
-            '_',         //  ▁    0xE4 -> LOWER ONE EIGHTH BLOCK
+            '\u2581',    //  ▁    0xE4 -> LOWER ONE EIGHTH BLOCK
             '\u258f',    //  ▏    0xE5 -> LEFT ONE EIGHTH BLOCK
             '\u2592',    //  ▒    0xE6 -> MEDIUM SHADE
             '\u2595',    //  ▕    0xE7 -> RIGHT ONE EIGHTH BLOCK
@@ -431,7 +432,7 @@ object Petscii {
             '\u258c',    //  ▌    0xA1 -> LEFT HALF BLOCK
             '\u2584',    //  ▄    0xA2 -> LOWER HALF BLOCK
             '\u2594',    //  ▔    0xA3 -> UPPER ONE EIGHTH BLOCK
-            '_',         //  ▁    0xA4 -> LOWER ONE EIGHTH BLOCK
+            '\u2581',    //  ▁    0xA4 -> LOWER ONE EIGHTH BLOCK
             '\u258f',    //  ▏    0xA5 -> LEFT ONE EIGHTH BLOCK
             '\u2592',    //  ▒    0xA6 -> MEDIUM SHADE
             '\u2595',    //  ▕    0xA7 -> RIGHT ONE EIGHTH BLOCK
@@ -495,7 +496,7 @@ object Petscii {
             '\u258c',    //  ▌    0xE1 -> LEFT HALF BLOCK
             '\u2584',    //  ▄    0xE2 -> LOWER HALF BLOCK
             '\u2594',    //  ▔    0xE3 -> UPPER ONE EIGHTH BLOCK
-            '_',         //  ▁    0xE4 -> LOWER ONE EIGHTH BLOCK
+            '\u2581',    //  ▁    0xE4 -> LOWER ONE EIGHTH BLOCK
             '\u258f',    //  ▏    0xE5 -> LEFT ONE EIGHTH BLOCK
             '\u2592',    //  ▒    0xE6 -> MEDIUM SHADE
             '\u2595',    //  ▕    0xE7 -> RIGHT ONE EIGHTH BLOCK
@@ -626,7 +627,7 @@ object Petscii {
             '\u258c',    //  ▌    0x61 -> LEFT HALF BLOCK
             '\u2584',    //  ▄    0x62 -> LOWER HALF BLOCK
             '\u2594',    //  ▔    0x63 -> UPPER ONE EIGHTH BLOCK
-            '_',         //  ▁    0x64 -> LOWER ONE EIGHTH BLOCK
+            '\u2581',    //  ▁    0x64 -> LOWER ONE EIGHTH BLOCK
             '\u258f',    //  ▏    0x65 -> LEFT ONE EIGHTH BLOCK
             '\u2592',    //  ▒    0x66 -> MEDIUM SHADE
             '\u2595',    //  ▕    0x67 -> RIGHT ONE EIGHTH BLOCK
@@ -885,7 +886,7 @@ object Petscii {
             '\u258c',    //  ▌    0x61 -> LEFT HALF BLOCK
             '\u2584',    //  ▄    0x62 -> LOWER HALF BLOCK
             '\u2594',    //  ▔    0x63 -> UPPER ONE EIGHTH BLOCK
-            '_',         //  ▁    0x64 -> LOWER ONE EIGHTH BLOCK
+            '\u2581',    //  ▁    0x64 -> LOWER ONE EIGHTH BLOCK
             '\u258f',    //  ▏    0x65 -> LEFT ONE EIGHTH BLOCK
             '\u2592',    //  ▒    0x66 -> MEDIUM SHADE
             '\u2595',    //  ▕    0x67 -> RIGHT ONE EIGHTH BLOCK
@@ -1049,51 +1050,90 @@ object Petscii {
     private val encodingScreencodeLowercase = decodingScreencodeLowercase.withIndex().associate{it.value to it.index}
     private val encodingScreencodeUppercase = decodingScreencodeUppercase.withIndex().associate{it.value to it.index}
 
+    private fun replaceSpecial(chr: Char): Char =
+        // characters often used in C like source code can be translated with a little bit of fantasy:
+        when(chr) {
+            '^' -> '↑'
+            '_' -> '▁'
+            '{' -> '┤'
+            '}' -> '├'
+            '|' -> '│'
+            '\\' -> '╲'
+            else -> chr
+        }
 
     fun encodePetscii(text: String, lowercase: Boolean = false): List<Short> {
-        val lookup = if(lowercase) encodingPetsciiLowercase else encodingPetsciiUppercase
-        return text.map {
-            val petscii = lookup[it]
-            petscii?.toShort() ?: when (it) {
+        fun encodeChar(chr3: Char, lowercase: Boolean): Short {
+            val chr = replaceSpecial(chr3)
+            val screencode = if(lowercase) encodingPetsciiLowercase[chr] else encodingPetsciiUppercase[chr]
+            return screencode?.toShort() ?: when (chr) {
                 '\u0000' -> 0.toShort()
                 in '\u8000'..'\u80ff' -> {
                     // special case: take the lower 8 bit hex value directly
-                    (it.toInt() - 0x8000).toShort()
+                    (chr.code - 0x8000).toShort()
                 }
                 else -> {
                     val case = if (lowercase) "lower" else "upper"
-                    throw CharConversionException("no ${case}case Petscii character for '$it' (${it.toShort()})")
+                    throw CharConversionException("no ${case}Petscii character for '${escape(chr.toString())}' (${chr.code})")
                 }
             }
         }
+
+        return text.map{
+            try {
+                encodeChar(it, lowercase)
+            } catch (x: CharConversionException) {
+                encodeChar(it, !lowercase)
+            }
+        }
     }
 
     fun decodePetscii(petscii: Iterable<Short>, lowercase: Boolean = false): String {
-        val decodeTable = if(lowercase) decodingPetsciiLowercase else decodingPetsciiUppercase
-        return petscii.map { decodeTable[it.toInt()] }.joinToString("")
+        return petscii.map {
+            val code = it.toInt()
+            try {
+                if(lowercase) decodingPetsciiLowercase[code] else decodingPetsciiUppercase[code]
+            } catch(x: CharConversionException) {
+                if(lowercase) decodingPetsciiUppercase[code] else decodingPetsciiLowercase[code]
+            }
+        }.joinToString("")
     }
 
     fun encodeScreencode(text: String, lowercase: Boolean = false): List<Short> {
-        val lookup = if(lowercase) encodingScreencodeLowercase else encodingScreencodeUppercase
-        return text.map{
-            val screencode = lookup[it]
-            screencode?.toShort() ?: when (it) {
+        fun encodeChar(chr3: Char, lowercase: Boolean): Short {
+            val chr = replaceSpecial(chr3)
+            val screencode = if(lowercase) encodingScreencodeLowercase[chr] else encodingScreencodeUppercase[chr]
+            return screencode?.toShort() ?: when (chr) {
                 '\u0000' -> 0.toShort()
                 in '\u8000'..'\u80ff' -> {
                     // special case: take the lower 8 bit hex value directly
-                    (it.toInt() - 0x8000).toShort()
+                    (chr.code - 0x8000).toShort()
                 }
                 else -> {
                     val case = if (lowercase) "lower" else "upper"
-                    throw CharConversionException("no ${case}Screencode character for '$it' (${it.toShort()})")
+                    throw CharConversionException("no ${case}Screencode character for '${escape(chr.toString())}' (${chr.code})")
                 }
             }
         }
+
+        return text.map{
+            try {
+                encodeChar(it, lowercase)
+            } catch (x: CharConversionException) {
+                encodeChar(it, !lowercase)
+            }
+        }
     }
 
     fun decodeScreencode(screencode: Iterable<Short>, lowercase: Boolean = false): String {
-        val decodeTable = if(lowercase) decodingScreencodeLowercase else decodingScreencodeUppercase
-        return screencode.map { decodeTable[it.toInt()] }.joinToString("")
+        return screencode.map {
+            val code = it.toInt()
+            try {
+                if (lowercase) decodingScreencodeLowercase[code] else decodingScreencodeUppercase[code]
+            } catch (x: CharConversionException) {
+                if (lowercase) decodingScreencodeUppercase[code] else decodingScreencodeLowercase[code]
+            }
+        }.joinToString("")
     }
 
     fun petscii2scr(petscii_code: Short, inverseVideo: Boolean): Short {

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

@@ -1,4 +1,4 @@
-package prog8.compiler.target.c64.codegen
+package prog8.compiler.target.cpu6502.codegen
 
 import prog8.ast.*
 import prog8.ast.antlr.escape
@@ -9,11 +9,10 @@ import prog8.compiler.*
 import prog8.compiler.functions.BuiltinFunctions
 import prog8.compiler.functions.FSignature
 import prog8.compiler.target.*
-import prog8.compiler.target.c64.AssemblyProgram
-import prog8.compiler.target.c64.Petscii
-import prog8.compiler.target.c64.codegen.assignment.AsmAssignment
-import prog8.compiler.target.c64.codegen.assignment.AssignmentAsmGen
-import java.io.CharConversionException
+import prog8.compiler.target.cbm.AssemblyProgram
+import prog8.compiler.target.cpu6502.codegen.assignment.AsmAssignment
+import prog8.compiler.target.cpu6502.codegen.assignment.AssignmentAsmGen
+import prog8.optimizer.CallGraph
 import java.nio.file.Path
 import java.nio.file.Paths
 import java.time.LocalDate
@@ -31,7 +30,8 @@ internal class AsmGen(private val program: Program,
 
     // for expressions and augmented assignments:
     val optimizedByteMultiplications = setOf(3,5,6,7,9,10,11,12,13,14,15,20,25,40,50,80,100)
-    val optimizedWordMultiplications = setOf(3,5,6,7,9,10,12,15,20,25,40,50,80,100,320)
+    val optimizedWordMultiplications = setOf(3,5,6,7,9,10,12,15,20,25,40,50,80,100,320,640)
+    private val callGraph = CallGraph(program)
 
     private val assemblyLines = mutableListOf<String>()
     private val globalFloatConsts = mutableMapOf<Double, String>()     // all float values in the entire program (value -> varname)
@@ -128,7 +128,7 @@ internal class AsmGen(private val program: Program,
                 out("* = ${program.actualLoadAddress.toHex()}")
                 val year = LocalDate.now().year
                 out("  .word  (+), $year")
-                out("  .null  $9e, format(' %d ', _prog8_entrypoint), $3a, $8f, ' prog8 by idj'")
+                out("  .null  $9e, format(' %d ', _prog8_entrypoint), $3a, $8f, ' prog8'")
                 out("+\t.word  0")
                 out("_prog8_entrypoint\t; assembly code starts here\n")
                 if(!options.noSysInit)
@@ -157,7 +157,16 @@ internal class AsmGen(private val program: Program,
                 pha""")
         }
 
-        out("  jmp  main.start  ; start program / force start proc to be included")
+        // make sure that on the cx16 and c64, basic rom is banked in again when we exit the program
+        when(compTarget.name) {
+            Cx16Target.name -> {
+                if(options.floats)
+                    out("  lda  #4 |  sta  $01")    // to use floats, make sure Basic rom is banked in
+                out("  jsr  main.start |  lda  #4 |  sta  $01 |  rts")
+            }
+            C64Target.name -> out("  jsr  main.start |  lda  #31 |  sta  $01 |  rts")
+            else -> jmp("main.start")
+        }
     }
 
     private fun slaballocations() {
@@ -246,15 +255,6 @@ internal class AsmGen(private val program: Program,
         } else assemblyLines.add(fragment)
     }
 
-    private fun encode(str: String, altEncoding: Boolean): List<Short> {
-        try {
-            val bytes = if (altEncoding) Petscii.encodeScreencode(str, true) else Petscii.encodePetscii(str, true)
-            return bytes.plus(0)
-        } catch(x: CharConversionException) {
-            throw AssemblyError("There was a problem converting a string to the target machine's char encoding: ${x.message}")
-        }
-    }
-
     private fun zeropagevars2asm(statements: List<Statement>) {
         out("; vars allocated on zeropage")
         val variables = statements.filterIsInstance<VarDecl>().filter { it.type==VarDeclType.VAR }
@@ -290,10 +290,9 @@ internal class AsmGen(private val program: Program,
             DataType.UWORD -> out("$name\t.word  0")
             DataType.WORD -> out("$name\t.sint  0")
             DataType.FLOAT -> out("$name\t.byte  0,0,0,0,0  ; float")
-            DataType.STRUCT -> {}       // is flattened
             DataType.STR -> {
                 val str = decl.value as StringLiteralValue
-                outputStringvar(decl, encode(str.value, str.altEncoding))
+                outputStringvar(decl, compTarget.encodeString(str.value, str.altEncoding).plus(0))
             }
             DataType.ARRAY_UB -> {
                 val data = makeArrayFillDataUnsigned(decl)
@@ -352,6 +351,9 @@ internal class AsmGen(private val program: Program,
                 for (f in array.zip(floatFills))
                     out("  .byte  ${f.second}  ; float ${f.first}")
             }
+            else -> {
+                throw AssemblyError("weird dt")
+            }
         }
     }
 
@@ -379,38 +381,28 @@ internal class AsmGen(private val program: Program,
         out("\n; non-zeropage variables")
         val vars = statements.filterIsInstance<VarDecl>().filter { it.type==VarDeclType.VAR }
 
-        // first output the flattened struct member variables *in order*
-        // after that, the other variables sorted by their datatype
-
-        val (structMembers, normalVars) = vars.partition { it.struct!=null }
-        structMembers.forEach { vardecl2asm(it) }
-
-        // special treatment for string types: merge strings that are identical
-        val encodedstringVars = normalVars
+        val encodedstringVars = vars
                 .filter {it.datatype == DataType.STR }
                 .map {
                     val str = it.value as StringLiteralValue
-                    it to encode(str.value, str.altEncoding)
+                    it to compTarget.encodeString(str.value, str.altEncoding).plus(0)
                 }
-                .groupBy({it.second}, {it.first})
-        for((encoded, variables) in encodedstringVars) {
-            variables.dropLast(1).forEach { out(it.name) }
-            val lastvar = variables.last()
-            outputStringvar(lastvar, encoded)
+        for((decl, variables) in encodedstringVars) {
+            outputStringvar(decl, variables)
         }
 
         // non-string variables
-        normalVars.filter{ it.datatype != DataType.STR }.sortedBy { it.datatype }.forEach {
+        vars.filter{ it.datatype != DataType.STR }.sortedBy { it.datatype }.forEach {
             if(it.makeScopedName(it.name) !in allocatedZeropageVariables)
                 vardecl2asm(it)
         }
     }
 
-    private fun outputStringvar(lastvar: VarDecl, encoded: List<Short>) {
-        val sv = lastvar.value as StringLiteralValue
+    private fun outputStringvar(strdecl: VarDecl, bytes: List<Short>) {
+        val sv = strdecl.value as StringLiteralValue
         val altEncoding = if(sv.altEncoding) "@" else ""
-        out("${lastvar.name}\t; ${lastvar.datatype} $altEncoding\"${escape(sv.value).replace("\u0000", "<NULL>")}\"")
-        val outputBytes = encoded.map { "$" + it.toString(16).padStart(2, '0') }
+        out("${strdecl.name}\t; ${strdecl.datatype} $altEncoding\"${escape(sv.value).replace("\u0000", "<NULL>")}\"")
+        val outputBytes = bytes.map { "$" + it.toString(16).padStart(2, '0') }
         for (chunk in outputBytes.chunked(16))
             out("  .byte  " + chunk.joinToString())
     }
@@ -437,10 +429,10 @@ internal class AsmGen(private val program: Program,
                         "$" + it.number.toInt().toString(16).padStart(4, '0')
                     }
                     is AddressOf -> {
-                        it.identifier.firstStructVarName(program) ?: asmSymbolName(it.identifier)
+                        asmSymbolName(it.identifier)
                     }
                     is IdentifierReference -> {
-                        it.firstStructVarName(program) ?: asmSymbolName(it)
+                        asmSymbolName(it)
                     }
                     else -> throw AssemblyError("weird array elt dt")
                 }
@@ -502,28 +494,19 @@ internal class AsmGen(private val program: Program,
     }
 
     internal fun asmSymbolName(identifier: IdentifierReference): String {
-        return if(identifier.memberOfStruct(program)!=null) {
-            val name = identifier.targetVarDecl(program)!!.name
-            fixNameSymbols(name)
-        } else {
-            fixNameSymbols(identifier.nameInSource.joinToString("."))
-        }
+        val target = identifier.targetStatement(program)
+        val prefix = if(target is Label) "_" else ""
+        return fixNameSymbols(prefix+identifier.nameInSource.joinToString("."))
     }
 
     internal fun asmSymbolName(regs: RegisterOrPair): String =
-        if(regs in Cx16VirtualRegisters)
-            "cx16." + regs.toString().toLowerCase()
+        if (regs in Cx16VirtualRegisters)
+            "cx16." + regs.toString().lowercase()
         else
             throw AssemblyError("no symbol name for register $regs")
 
-    internal fun asmVariableName(identifier: IdentifierReference): String {
-        return if(identifier.memberOfStruct(program)!=null) {
-            val name = identifier.targetVarDecl(program)!!.name
-            fixNameSymbols(name)
-        } else {
-            fixNameSymbols(identifier.nameInSource.joinToString("."))
-        }
-    }
+    internal fun asmVariableName(identifier: IdentifierReference) =
+        fixNameSymbols(identifier.nameInSource.joinToString("."))
 
     internal fun asmSymbolName(name: String) = fixNameSymbols(name)
     internal fun asmVariableName(name: String) = fixNameSymbols(name)
@@ -671,7 +654,7 @@ internal class AsmGen(private val program: Program,
         when(stmt) {
             is ParameterVarDecl -> { /* subroutine parameter vardecls don't get any special treatment here */ }
             is VarDecl -> translate(stmt)
-            is StructDecl, is NopStatement -> {}
+            is NopStatement -> {}
             is Directive -> translate(stmt)
             is Return -> translate(stmt)
             is Subroutine -> translateSubroutine(stmt)
@@ -695,7 +678,7 @@ internal class AsmGen(private val program: Program,
             is Break -> {
                 if(loopEndLabels.isEmpty())
                     throw AssemblyError("break statement out of context  ${stmt.position}")
-                out("  jmp  ${loopEndLabels.peek()}")
+                jmp(loopEndLabels.peek())
             }
             is WhileLoop -> translate(stmt)
             is RepeatLoop -> translate(stmt)
@@ -708,48 +691,58 @@ internal class AsmGen(private val program: Program,
         }
     }
 
-    internal fun loadScaledArrayIndexIntoRegister(expr: ArrayIndexedExpression,
-                                                  elementDt: DataType,
-                                                  register: CpuRegister,
-                                                  addOneExtra: Boolean=false) {
-        val reg = register.toString().toLowerCase()
+    internal fun loadScaledArrayIndexIntoRegister(
+        expr: ArrayIndexedExpression,
+        elementDt: DataType,
+        register: CpuRegister,
+        addOneExtra: Boolean = false
+    ) {
+        val reg = register.toString().lowercase()
         val indexnum = expr.indexer.constIndex()
-        if(indexnum!=null) {
-            val indexValue = indexnum * compTarget.memorySize(elementDt) + if(addOneExtra) 1 else 0
+        if (indexnum != null) {
+            val indexValue = indexnum * compTarget.memorySize(elementDt) + if (addOneExtra) 1 else 0
             out("  ld$reg  #$indexValue")
             return
         }
 
-        val indexName = asmVariableName(expr.indexer.indexVar!!)
-        if(addOneExtra) {
+        val indexVar = expr.indexer.indexExpr as? IdentifierReference
+            ?: throw AssemblyError("array indexer should have been replaced with a temp var @ ${expr.indexer.position}")
+
+        val indexName = asmVariableName(indexVar)
+        if (addOneExtra) {
             // add 1 to the result
-            when(elementDt) {
+            when (elementDt) {
                 in ByteDatatypes -> {
                     out("  ldy  $indexName |  iny")
-                    when(register) {
+                    when (register) {
                         CpuRegister.A -> out(" tya")
                         CpuRegister.X -> out(" tyx")
-                        CpuRegister.Y -> {}
+                        CpuRegister.Y -> {
+                        }
                     }
                 }
                 in WordDatatypes -> {
                     out("  lda  $indexName |  sec |  rol a")
-                    when(register) {
-                        CpuRegister.A -> {}
+                    when (register) {
+                        CpuRegister.A -> {
+                        }
                         CpuRegister.X -> out(" tax")
                         CpuRegister.Y -> out(" tay")
                     }
                 }
                 DataType.FLOAT -> {
-                    require(compTarget.memorySize(DataType.FLOAT)==5)
-                    out("""
+                    require(compTarget.memorySize(DataType.FLOAT) == 5)
+                    out(
+                        """
                                 lda  $indexName
                                 asl  a
                                 asl  a
                                 sec
-                                adc  $indexName""")
-                    when(register) {
-                        CpuRegister.A -> {}
+                                adc  $indexName"""
+                    )
+                    when (register) {
+                        CpuRegister.A -> {
+                        }
                         CpuRegister.X -> out(" tax")
                         CpuRegister.Y -> out(" tay")
                     }
@@ -757,26 +750,30 @@ internal class AsmGen(private val program: Program,
                 else -> throw AssemblyError("weird dt")
             }
         } else {
-            when(elementDt) {
+            when (elementDt) {
                 in ByteDatatypes -> out("  ld$reg  $indexName")
                 in WordDatatypes -> {
                     out("  lda  $indexName |  asl a")
-                    when(register) {
-                        CpuRegister.A -> {}
+                    when (register) {
+                        CpuRegister.A -> {
+                        }
                         CpuRegister.X -> out(" tax")
                         CpuRegister.Y -> out(" tay")
                     }
                 }
                 DataType.FLOAT -> {
-                    require(compTarget.memorySize(DataType.FLOAT)==5)
-                    out("""
+                    require(compTarget.memorySize(DataType.FLOAT) == 5)
+                    out(
+                        """
                                 lda  $indexName
                                 asl  a
                                 asl  a
                                 clc
-                                adc  $indexName""")
-                    when(register) {
-                        CpuRegister.A -> {}
+                                adc  $indexName"""
+                    )
+                    when (register) {
+                        CpuRegister.A -> {
+                        }
                         CpuRegister.X -> out(" tax")
                         CpuRegister.Y -> out(" tay")
                     }
@@ -818,9 +815,18 @@ internal class AsmGen(private val program: Program,
 
 
     private fun translateSubroutine(sub: Subroutine) {
+        var onlyVariables = false
+
         if(sub.inline) {
-            if(options.optimize)
-                return      // inline subroutines don't exist anymore on their own
+            if(options.optimize) {
+                if(sub.isAsmSubroutine ||callGraph.unused(sub))
+                    return
+
+                // from an inlined subroutine only the local variables are generated,
+                // all other code statements are omitted in the subroutine itself
+                // (they've been inlined at the call site, remember?)
+                onlyVariables = true
+            }
             else if(sub.amountOfRtsInAsm()==0) {
                 // make sure the NOT INLINED subroutine actually does an rts at the end
                 sub.statements.add(Return(null, Position.DUMMY))
@@ -837,7 +843,7 @@ internal class AsmGen(private val program: Program,
 
             // asmsub with most likely just an inline asm in it
             out("${sub.name}\t.proc")
-            sub.statements.forEach{ translate(it) }
+            sub.statements.forEach { translate(it) }
             out("  .pend\n")
         } else {
             // regular subroutine
@@ -861,8 +867,10 @@ internal class AsmGen(private val program: Program,
                     clc""")
             }
 
-            out("; statements")
-            sub.statements.forEach{ translate(it) }
+            if(!onlyVariables) {
+                out("; statements")
+                sub.statements.forEach { translate(it) }
+            }
 
             for(removal in removals.toList()) {
                 if(removal.second==sub) {
@@ -872,7 +880,15 @@ internal class AsmGen(private val program: Program,
             }
 
             out("; variables")
-            out("; register saves")
+            for((dt, name, addr) in sub.asmGenInfo.extraVars) {
+                if(addr!=null)
+                    out("$name = $addr")
+                else when(dt) {
+                    DataType.UBYTE -> out("$name    .byte  0")
+                    DataType.UWORD -> out("$name    .word  0")
+                    else -> throw AssemblyError("weird dt")
+                }
+            }
             if(sub.asmGenInfo.usedRegsaveA)
                 out("_prog8_regsaveA     .byte  0")
             if(sub.asmGenInfo.usedRegsaveX)
@@ -880,9 +896,9 @@ internal class AsmGen(private val program: Program,
             if(sub.asmGenInfo.usedRegsaveY)
                 out("_prog8_regsaveY     .byte  0")
             if(sub.asmGenInfo.usedFloatEvalResultVar1)
-                out("$subroutineFloatEvalResultVar1    .byte 0,0,0,0,0")
+                out("$subroutineFloatEvalResultVar1    .byte  0,0,0,0,0")
             if(sub.asmGenInfo.usedFloatEvalResultVar2)
-                out("$subroutineFloatEvalResultVar2    .byte 0,0,0,0,0")
+                out("$subroutineFloatEvalResultVar2    .byte  0,0,0,0,0")
             vardecls2asm(sub.statements)
             out("  .pend\n")
         }
@@ -917,6 +933,10 @@ internal class AsmGen(private val program: Program,
         checkBooleanExpression(stmt.condition)  // we require the condition to be of the form  'x <comparison> <value>'
         val booleanCondition = stmt.condition as BinaryExpression
 
+        // DISABLED FOR NOW:
+//        if(!booleanCondition.left.isSimple || !booleanCondition.right.isSimple)
+//            throw AssemblyError("both operands for if comparison expression should have been simplified")
+
         if (stmt.elsepart.containsNoCodeNorVars()) {
             // empty else
             val endLabel = makeLabel("if_end")
@@ -930,7 +950,7 @@ internal class AsmGen(private val program: Program,
             val endLabel = makeLabel("if_end")
             expressionsAsmGen.translateComparisonExpressionWithJumpIfFalse(booleanCondition, elseLabel)
             translate(stmt.truepart)
-            out("  jmp  $endLabel")
+            jmp(endLabel)
             out(elseLabel)
             translate(stmt.elsepart)
             out(endLabel)
@@ -952,7 +972,7 @@ internal class AsmGen(private val program: Program,
                 // endless loop
                 out(repeatLabel)
                 translate(stmt.body)
-                out("  jmp  $repeatLabel")
+                jmp(repeatLabel)
                 out(endLabel)
             }
             is NumericLiteralValue -> {
@@ -963,11 +983,11 @@ internal class AsmGen(private val program: Program,
                     iterations == 0 -> {}
                     iterations <= 256 -> {
                         out("  lda  #${iterations and 255}")
-                        repeatByteCountInA(iterations, repeatLabel, endLabel, stmt.body)
+                        repeatByteCountInA(iterations, repeatLabel, endLabel, stmt)
                     }
                     else -> {
                         out("  lda  #<${iterations} |  ldy  #>${iterations}")
-                        repeatWordCountInAY(iterations, repeatLabel, endLabel, stmt.body)
+                        repeatWordCountInAY(iterations, repeatLabel, endLabel, stmt)
                     }
                 }
             }
@@ -976,10 +996,12 @@ internal class AsmGen(private val program: Program,
                 val name = asmVariableName(stmt.iterations as IdentifierReference)
                 when(vardecl.datatype) {
                     DataType.UBYTE, DataType.BYTE -> {
-                        repeatByteCountVar(name, repeatLabel, endLabel, stmt.body)
+                        assignVariableToRegister(name, RegisterOrPair.A)
+                        repeatByteCountInA(null, repeatLabel, endLabel, stmt)
                     }
                     DataType.UWORD, DataType.WORD -> {
-                        repeatWordCountVar(name, repeatLabel, endLabel, stmt.body)
+                        assignVariableToRegister(name, RegisterOrPair.AY)
+                        repeatWordCountInAY(null, repeatLabel, endLabel, stmt)
                     }
                     else -> throw AssemblyError("invalid loop variable datatype $vardecl")
                 }
@@ -988,14 +1010,14 @@ internal class AsmGen(private val program: Program,
                 val dt = stmt.iterations!!.inferType(program)
                 if(!dt.isKnown)
                     throw AssemblyError("unknown dt")
-                when (dt.typeOrElse(DataType.STRUCT)) {
+                when (dt.typeOrElse(DataType.UNDEFINED)) {
                     in ByteDatatypes -> {
                         assignExpressionToRegister(stmt.iterations!!, RegisterOrPair.A)
-                        repeatByteCountInA(null, repeatLabel, endLabel, stmt.body)
+                        repeatByteCountInA(null, repeatLabel, endLabel, stmt)
                     }
                     in WordDatatypes -> {
                         assignExpressionToRegister(stmt.iterations!!, RegisterOrPair.AY)
-                        repeatWordCountInAY(null, repeatLabel, endLabel, stmt.body)
+                        repeatWordCountInAY(null, repeatLabel, endLabel, stmt)
                     }
                     else -> throw AssemblyError("invalid loop expression datatype $dt")
                 }
@@ -1005,12 +1027,13 @@ internal class AsmGen(private val program: Program,
         loopEndLabels.pop()
     }
 
-    private fun repeatWordCountInAY(constIterations: Int?, repeatLabel: String, endLabel: String, body: AnonymousScope) {
+    private fun repeatWordCountInAY(constIterations: Int?, repeatLabel: String, endLabel: String, stmt: RepeatLoop) {
+        // note: A/Y must have been loaded with the number of iterations!
         if(constIterations==0)
             return
-        // note: A/Y must have been loaded with the number of iterations already!
-        // TODO can be even more optimized by iterating over pages
-        val counterVar = makeLabel("repeatcounter")
+        // no need to explicitly test for 0 iterations as this is done in the count down logic below
+
+        val counterVar: String = createRepeatCounterVar(DataType.UWORD, constIterations, stmt)
         out("""
                 sta  $counterVar
                 sty  $counterVar+1
@@ -1018,81 +1041,72 @@ $repeatLabel    lda  $counterVar
                 bne  +
                 lda  $counterVar+1
                 beq  $endLabel
-+               lda  $counterVar
+                lda  $counterVar
                 bne  +
                 dec  $counterVar+1
 +               dec  $counterVar
 """)
-        translate(body)
-        out("  jmp  $repeatLabel")
-        if(constIterations!=null && constIterations>=16 && zeropage.available() > 1) {
-            // allocate count var on ZP
-            val zpAddr = zeropage.allocate(counterVar, DataType.UWORD, body.position, errors)
-            out("""$counterVar = $zpAddr  ; auto zp UWORD""")
-        } else {
-            out("""
-$counterVar    .word  0""")
-        }
+        translate(stmt.body)
+        jmp(repeatLabel)
         out(endLabel)
-
     }
 
-    private fun repeatByteCountInA(constIterations: Int?, repeatLabel: String, endLabel: String, body: AnonymousScope) {
+    private fun repeatByteCountInA(constIterations: Int?, repeatLabel: String, endLabel: String, stmt: RepeatLoop) {
+        // note: A must have been loaded with the number of iterations!
         if(constIterations==0)
             return
-        // note: A must have been loaded with the number of iterations already!
-        val counterVar = makeLabel("repeatcounter")
+
         if(constIterations==null)
-            out("  beq  $endLabel")
+            out("  beq  $endLabel   ; skip loop if zero iters")
+        val counterVar = createRepeatCounterVar(DataType.UBYTE, constIterations, stmt)
         out("  sta  $counterVar")
         out(repeatLabel)
-        translate(body)
-        out("""
-             dec  $counterVar
-             bne  $repeatLabel
-             beq  $endLabel  
-$counterVar    .byte  0""")
-        out(endLabel)
-    }
-
-    private fun repeatByteCountVar(repeatCountVar: String, repeatLabel: String, endLabel: String, body: AnonymousScope) {
-        // note: cannot use original counter variable because it should retain its original value
-        val counterVar = makeLabel("repeatcounter")
-        out("  lda  $repeatCountVar |  beq  $endLabel |  sta  $counterVar")
-        out(repeatLabel)
-        translate(body)
+        translate(stmt.body)
         out("  dec  $counterVar |  bne  $repeatLabel")
-        // inline countervar:
-        out("""
-                beq  $endLabel  
-$counterVar    .byte  0""")
-        out(endLabel)
+        if(constIterations==null)
+            out(endLabel)
     }
 
-    private fun repeatWordCountVar(repeatCountVar: String, repeatLabel: String, endLabel: String, body: AnonymousScope) {
-        // TODO can be even more optimized by iterating over pages
-        // note: cannot use original counter variable because it should retain its original value
+    private fun createRepeatCounterVar(dt: DataType, constIterations: Int?, stmt: RepeatLoop): String {
+        val asmInfo = stmt.definingSubroutine()!!.asmGenInfo
+        var parent = stmt.parent
+        while(parent !is ParentSentinel) {
+            if(parent is RepeatLoop)
+                break
+            parent = parent.parent
+        }
+        val isNested = parent is RepeatLoop
+
+        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 }
+            if(existingVar!=null)
+                return existingVar.second
+        }
+
         val counterVar = makeLabel("repeatcounter")
-        out("""
-            lda  $repeatCountVar
-            sta  $counterVar
-            ora  $repeatCountVar+1
-            beq  $endLabel
-            lda  $repeatCountVar+1
-            sta  $counterVar+1""")
-        out(repeatLabel)
-        translate(body)
-        out("""
-            lda  $counterVar
-            bne  +
-            dec  $counterVar+1
-+           dec  $counterVar
-            lda  $counterVar
-            ora  $counterVar+1
-            bne  $repeatLabel
-            beq  $endLabel  
-$counterVar    .word  0""")
-        out(endLabel)
+        when(dt) {
+            DataType.UBYTE -> {
+                if(constIterations!=null && constIterations>=16 && zeropage.hasByteAvailable()) {
+                    // allocate count var on ZP
+                    val zpAddr = zeropage.allocate(counterVar, DataType.UBYTE, stmt.position, errors)
+                    asmInfo.extraVars.add(Triple(DataType.UBYTE, counterVar, zpAddr))
+                } else {
+                    asmInfo.extraVars.add(Triple(DataType.UBYTE, counterVar, null))
+                }
+            }
+            DataType.UWORD -> {
+                if(constIterations!=null && constIterations>=16 && zeropage.hasWordAvailable()) {
+                    // allocate count var on ZP
+                    val zpAddr = zeropage.allocate(counterVar, DataType.UWORD, stmt.position, errors)
+                    asmInfo.extraVars.add(Triple(DataType.UWORD, counterVar, zpAddr))
+                } else {
+                    asmInfo.extraVars.add(Triple(DataType.UWORD, counterVar, null))
+                }
+            }
+            else -> throw AssemblyError("invalidt dt")
+        }
+        return counterVar
     }
 
     private fun translate(stmt: WhileLoop) {
@@ -1104,7 +1118,7 @@ $counterVar    .word  0""")
         out(whileLabel)
         expressionsAsmGen.translateComparisonExpressionWithJumpIfFalse(booleanCondition, endLabel)
         translate(stmt.body)
-        out("  jmp  $whileLabel")
+        jmp(whileLabel)
         out(endLabel)
         loopEndLabels.pop()
     }
@@ -1138,7 +1152,7 @@ $counterVar    .word  0""")
             if(choice.values==null) {
                 // the else choice
                 translate(choice.statements)
-                out("  jmp  $endLabel")
+                jmp(endLabel)
             } else {
                 choiceBlocks.add(choiceLabel to choice.statements)
                 for (cv in choice.values!!) {
@@ -1157,11 +1171,11 @@ $counterVar    .word  0""")
                 }
             }
         }
-        out("  jmp  $endLabel")
+        jmp(endLabel)
         for(choiceBlock in choiceBlocks) {
             out(choiceBlock.first)
             translate(choiceBlock.second)
-            out("  jmp  $endLabel")
+            jmp(endLabel)
         }
         out(endLabel)
     }
@@ -1220,7 +1234,7 @@ $counterVar    .word  0""")
                 val endLabel = makeLabel("branch_end")
                 out("  $instruction  $elseLabel")
                 translate(stmt.truepart)
-                out("  jmp  $endLabel")
+                jmp(endLabel)
                 out(elseLabel)
                 translate(stmt.elsepart)
                 out(endLabel)
@@ -1253,12 +1267,7 @@ $counterVar    .word  0""")
         when(stmt.directive) {
             "%asminclude" -> {
                 val sourcecode = loadAsmIncludeFile(stmt.args[0].str!!, stmt.definingModule().source)
-                val scopeprefix = stmt.args[1].str ?: ""
-                if(scopeprefix.isNotBlank())
-                    out("$scopeprefix\t.proc")
                 assemblyLines.add(sourcecode.trimEnd().trimStart('\n'))
-                if(scopeprefix.isNotBlank())
-                    out("  .pend\n")
             }
             "%asmbinary" -> {
                 val offset = if(stmt.args.size>1) ", ${stmt.args[1].int}" else ""
@@ -1277,30 +1286,21 @@ $label              nop""")
         }
     }
 
-    private fun translate(jmp: Jump) {
-        out("  jmp  ${getJumpTarget(jmp)}")
-    }
+    private fun translate(jump: Jump) = jmp(getJumpTarget(jump))
 
-    private fun getJumpTarget(jmp: Jump): String {
-        val ident = jmp.identifier
-        val label = jmp.generatedLabel
-        val addr = jmp.address
+    private fun getJumpTarget(jump: Jump): String {
+        val ident = jump.identifier
+        val label = jump.generatedLabel
+        val addr = jump.address
         return when {
-            ident!=null -> {
-                val target = ident.targetStatement(program)
-                val asmName = asmSymbolName(ident)
-                if(target is Label)
-                    "_$asmName"  // prefix with underscore to jump to local label
-                else
-                    asmName
-            }
+            ident!=null -> asmSymbolName(ident)
             label!=null -> label
             addr!=null -> addr.toHex()
             else -> "????"
         }
     }
 
-    private fun translate(ret: Return) {
+    internal fun translate(ret: Return, withRts: Boolean=true) {
         ret.value?.let { returnvalue ->
             val sub = ret.definingSubroutine()!!
             val returnType = sub.returntypes.single()
@@ -1319,7 +1319,9 @@ $label              nop""")
                 }
             }
         }
-        out("  rts")
+
+        if(withRts)
+            out("  rts")
     }
 
     private fun translate(asm: InlineAssembly) {
@@ -1378,6 +1380,13 @@ $label              nop""")
         return vardecl.makeScopedName(vardecl.name) in allocatedZeropageVariables
     }
 
+    internal fun jmp(asmLabel: String) {
+        if(isTargetCpu(CpuType.CPU65c02))
+            out("  bra  $asmLabel")     // note: 64tass will convert this automatically to a jmp if the relative distance is too large
+        else
+            out("  jmp  $asmLabel")
+    }
+
     internal fun pointerViaIndexRegisterPossible(pointerOffsetExpr: Expression): Pair<Expression, Expression>? {
         if(pointerOffsetExpr is BinaryExpression && pointerOffsetExpr.operator=="+") {
             val leftDt = pointerOffsetExpr.left.inferType(program)

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

@@ -1,4 +1,4 @@
-package prog8.compiler.target.c64.codegen
+package prog8.compiler.target.cpu6502.codegen
 
 
 // note: see https://wiki.nesdev.com/w/index.php/6502_assembly_optimisations

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

@@ -1,4 +1,4 @@
-package prog8.compiler.target.c64.codegen
+package prog8.compiler.target.cpu6502.codegen
 
 import prog8.ast.IFunctionCall
 import prog8.ast.Node
@@ -13,7 +13,8 @@ import prog8.ast.toHex
 import prog8.compiler.AssemblyError
 import prog8.compiler.functions.FSignature
 import prog8.compiler.target.CpuType
-import prog8.compiler.target.c64.codegen.assignment.*
+import prog8.compiler.target.Cx16Target
+import prog8.compiler.target.cpu6502.codegen.assignment.*
 import prog8.compiler.target.subroutineFloatEvalResultVar2
 
 internal class BuiltinFunctionsAsmGen(private val program: Program, private val asmgen: AsmGen, private val assignAsmGen: AssignmentAsmGen) {
@@ -64,7 +65,181 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
             "peek" -> throw AssemblyError("peek() should have been replaced by @()")
             "pokew" -> funcPokeW(fcall)
             "poke" -> throw AssemblyError("poke() should have been replaced by @()")
-            else -> TODO("missing asmgen for builtin func ${func.name}")
+            "cmp" -> funcCmp(fcall)
+            "callfar" -> funcCallFar(fcall)
+            "callrom" -> funcCallRom(fcall)
+            else -> throw AssemblyError("missing asmgen for builtin func ${func.name}")
+        }
+    }
+
+    private fun funcCallFar(fcall: IFunctionCall) {
+        if(asmgen.options.compTarget !is Cx16Target)
+            throw AssemblyError("callfar only works on cx16 target at this time")
+
+        val bank = fcall.args[0].constValue(program)?.number?.toInt()
+        val address = fcall.args[1].constValue(program)?.number?.toInt()
+        if(bank==null || address==null)
+            throw AssemblyError("callfar (jsrfar) requires constant arguments")
+
+        if(address !in 0xa000..0xbfff)
+            throw AssemblyError("callfar done on address outside of cx16 banked ram")
+        if(bank==0)
+            throw AssemblyError("callfar done on bank 0 which is reserved for the kernal")
+
+        val argAddrArg = fcall.args[2]
+        if(argAddrArg.constValue(program)?.number == 0) {
+            asmgen.out("""
+                jsr  cx16.jsrfar
+                .word  ${address.toHex()}
+                .byte  ${bank.toHex()}""")
+        } else {
+            when(argAddrArg) {
+                is AddressOf -> {
+                    if(argAddrArg.identifier.targetVarDecl(program)?.datatype != DataType.UBYTE)
+                        throw AssemblyError("callfar done with 'arg' pointer to variable that's not UBYTE")
+                    asmgen.out("""
+                        lda  ${asmgen.asmVariableName(argAddrArg.identifier)}
+                        jsr  cx16.jsrfar
+                        .word  ${address.toHex()}
+                        .byte  ${bank.toHex()}
+                        sta  ${asmgen.asmVariableName(argAddrArg.identifier)}""")
+                }
+                is NumericLiteralValue -> {
+                    asmgen.out("""
+                        lda  ${argAddrArg.number.toHex()}
+                        jsr  cx16.jsrfar
+                        .word  ${address.toHex()}
+                        .byte  ${bank.toHex()}
+                        sta  ${argAddrArg.number.toHex()}""")
+                }
+                else -> throw AssemblyError("callfar only accepts pointer-of a (ubyte) variable or constant memory address for the 'arg' parameter")
+            }
+        }
+    }
+
+    private fun funcCallRom(fcall: IFunctionCall) {
+        if(asmgen.options.compTarget !is Cx16Target)
+            throw AssemblyError("callrom only works on cx16 target at this time")
+
+        val bank = fcall.args[0].constValue(program)?.number?.toInt()
+        val address = fcall.args[1].constValue(program)?.number?.toInt()
+        if(bank==null || address==null)
+            throw AssemblyError("callrom requires constant arguments")
+
+        if(address !in 0xc000..0xffff)
+            throw AssemblyError("callrom done on address outside of cx16 banked rom")
+        if(bank>=32)
+            throw AssemblyError("callrom bank must be <32")
+
+        val argAddrArg = fcall.args[2]
+        if(argAddrArg.constValue(program)?.number == 0) {
+            asmgen.out("""
+                lda  $01
+                pha
+                lda  #${bank}
+                sta  $01
+                jsr  ${address.toHex()}
+                pla
+                sta  $01""")
+        } else {
+            when(argAddrArg) {
+                is AddressOf -> {
+                    if(argAddrArg.identifier.targetVarDecl(program)?.datatype != DataType.UBYTE)
+                        throw AssemblyError("callrom done with 'arg' pointer to variable that's not UBYTE")
+                    asmgen.out("""
+                        lda  $01
+                        pha
+                        lda  #${bank}
+                        sta  $01
+                        lda  ${asmgen.asmVariableName(argAddrArg.identifier)}                
+                        jsr  ${address.toHex()}
+                        sta  ${asmgen.asmVariableName(argAddrArg.identifier)}
+                        pla
+                        sta  $01""")
+                }
+                is NumericLiteralValue -> {
+                    asmgen.out("""
+                        lda  $01
+                        pha
+                        lda  #${bank}
+                        sta  $01
+                        lda  ${argAddrArg.number.toHex()}
+                        jsr  ${address.toHex()}
+                        sta  ${argAddrArg.number.toHex()}
+                        pla
+                        sta  $01""")
+                }
+                else -> throw AssemblyError("callrom only accepts pointer-of a (ubyte) variable or constant memory address for the 'arg' parameter")
+            }
+        }
+    }
+
+    private fun funcCmp(fcall: IFunctionCall) {
+        val arg1 = fcall.args[0]
+        val arg2 = fcall.args[1]
+        val dt1 = arg1.inferType(program).typeOrElse(DataType.UNDEFINED)
+        val dt2 = arg2.inferType(program).typeOrElse(DataType.UNDEFINED)
+        if(dt1 in ByteDatatypes) {
+            if(dt2 in ByteDatatypes) {
+                when (arg2) {
+                    is IdentifierReference -> {
+                        asmgen.assignExpressionToRegister(arg1, RegisterOrPair.A)
+                        asmgen.out("  cmp  ${asmgen.asmVariableName(arg2)}")
+                    }
+                    is NumericLiteralValue -> {
+                        asmgen.assignExpressionToRegister(arg1, RegisterOrPair.A)
+                        asmgen.out("  cmp  #${arg2.number}")
+                    }
+                    is DirectMemoryRead -> {
+                        if(arg2.addressExpression is NumericLiteralValue) {
+                            asmgen.assignExpressionToRegister(arg1, RegisterOrPair.A)
+                            asmgen.out("  cmp  ${arg2.addressExpression.constValue(program)!!.number.toHex()}")
+                        } else {
+                            asmgen.assignExpressionToVariable(arg2, "P8ZP_SCRATCH_B1", DataType.UBYTE, (fcall as Node).definingSubroutine())
+                            asmgen.assignExpressionToRegister(arg1, RegisterOrPair.A)
+                            asmgen.out("  cmp  P8ZP_SCRATCH_B1")
+                        }
+                    }
+                    else -> {
+                        asmgen.assignExpressionToVariable(arg2, "P8ZP_SCRATCH_B1", DataType.UBYTE, (fcall as Node).definingSubroutine())
+                        asmgen.assignExpressionToRegister(arg1, RegisterOrPair.A)
+                        asmgen.out("  cmp  P8ZP_SCRATCH_B1")
+                    }
+                }
+            } else
+                throw AssemblyError("args for cmp() should have same dt")
+        } else {
+            // dt1 is a word
+            if(dt2 in WordDatatypes) {
+                when (arg2) {
+                    is IdentifierReference -> {
+                        asmgen.assignExpressionToRegister(arg1, RegisterOrPair.AY)
+                        asmgen.out("""
+                            cpy  ${asmgen.asmVariableName(arg2)}+1
+                            bne  +
+                            cmp  ${asmgen.asmVariableName(arg2)}
++""")
+                    }
+                    is NumericLiteralValue -> {
+                        asmgen.assignExpressionToRegister(arg1, RegisterOrPair.AY)
+                        asmgen.out("""
+                            cpy  #>${arg2.number}
+                            bne  +
+                            cmp  #<${arg2.number}
++""")
+                    }
+                    else -> {
+                        asmgen.assignExpressionToVariable(arg2, "P8ZP_SCRATCH_W1", DataType.UWORD, (fcall as Node).definingSubroutine())
+                        asmgen.assignExpressionToRegister(arg1, RegisterOrPair.AY)
+                        asmgen.out("""
+                            cpy  P8ZP_SCRATCH_W1+1
+                            bne  +
+                            cmp  P8ZP_SCRATCH_W1
++""")
+                    }
+                }
+            } else
+                throw AssemblyError("args for cmp() should have same dt")
         }
     }
 
@@ -193,7 +368,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
     private fun funcRor2(fcall: IFunctionCall) {
         val what = fcall.args.single()
         val dt = what.inferType(program)
-        when (dt.typeOrElse(DataType.STRUCT)) {
+        when (dt.typeOrElse(DataType.UNDEFINED)) {
             DataType.UBYTE -> {
                 when (what) {
                     is ArrayIndexedExpression -> {
@@ -236,7 +411,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
     private fun funcRor(fcall: IFunctionCall) {
         val what = fcall.args.single()
         val dt = what.inferType(program)
-        when (dt.typeOrElse(DataType.STRUCT)) {
+        when (dt.typeOrElse(DataType.UNDEFINED)) {
             DataType.UBYTE -> {
                 when (what) {
                     is ArrayIndexedExpression -> {
@@ -294,7 +469,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
     private fun funcRol2(fcall: IFunctionCall) {
         val what = fcall.args.single()
         val dt = what.inferType(program)
-        when (dt.typeOrElse(DataType.STRUCT)) {
+        when (dt.typeOrElse(DataType.UNDEFINED)) {
             DataType.UBYTE -> {
                 when (what) {
                     is ArrayIndexedExpression -> {
@@ -337,7 +512,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
     private fun funcRol(fcall: IFunctionCall) {
         val what = fcall.args.single()
         val dt = what.inferType(program)
-        when (dt.typeOrElse(DataType.STRUCT)) {
+        when (dt.typeOrElse(DataType.UNDEFINED)) {
             DataType.UBYTE -> {
                 when (what) {
                     is ArrayIndexedExpression -> {
@@ -394,8 +569,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
 
     private fun translateRolRorArrayArgs(arrayvar: IdentifierReference, indexer: ArrayIndex, operation: String, dt: Char) {
         asmgen.assignExpressionToVariable(AddressOf(arrayvar, arrayvar.position), "prog8_lib.${operation}_array_u${dt}._arg_target", DataType.UWORD, null)
-        val indexerExpr = if(indexer.indexVar!=null) indexer.indexVar!! else indexer.indexNum!!
-        asmgen.assignExpressionToVariable(indexerExpr, "prog8_lib.${operation}_array_u${dt}._arg_index", DataType.UBYTE, null)
+        asmgen.assignExpressionToVariable(indexer.indexExpr, "prog8_lib.${operation}_array_u${dt}._arg_index", DataType.UBYTE, null)
     }
 
     private fun funcVariousFloatFuncs(fcall: IFunctionCall, func: FSignature, resultToStack: Boolean, resultRegister: RegisterOrPair?, scope: Subroutine?) {
@@ -412,7 +586,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
         translateArguments(fcall.args, func, scope)
         val dt = fcall.args.single().inferType(program)
         if(resultToStack) {
-            when (dt.typeOrElse(DataType.STRUCT)) {
+            when (dt.typeOrElse(DataType.UNDEFINED)) {
                 DataType.UBYTE -> asmgen.out("  jsr  prog8_lib.func_sign_ub_stack")
                 DataType.BYTE -> asmgen.out("  jsr  prog8_lib.func_sign_b_stack")
                 DataType.UWORD -> asmgen.out("  jsr  prog8_lib.func_sign_uw_stack")
@@ -421,7 +595,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                 else -> throw AssemblyError("weird type $dt")
             }
         } else {
-            when (dt.typeOrElse(DataType.STRUCT)) {
+            when (dt.typeOrElse(DataType.UNDEFINED)) {
                 DataType.UBYTE -> asmgen.out("  jsr  prog8_lib.func_sign_ub_into_A")
                 DataType.BYTE -> asmgen.out("  jsr  prog8_lib.func_sign_b_into_A")
                 DataType.UWORD -> asmgen.out("  jsr  prog8_lib.func_sign_uw_into_A")
@@ -437,14 +611,14 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
         outputAddressAndLenghtOfArray(fcall.args[0])
         val dt = fcall.args.single().inferType(program)
         if(resultToStack) {
-            when (dt.typeOrElse(DataType.STRUCT)) {
+            when (dt.typeOrElse(DataType.UNDEFINED)) {
                 DataType.ARRAY_B, DataType.ARRAY_UB, DataType.STR -> asmgen.out("  jsr  prog8_lib.func_${function.name}_b_stack")
                 DataType.ARRAY_UW, DataType.ARRAY_W -> asmgen.out("  jsr  prog8_lib.func_${function.name}_w_stack")
                 DataType.ARRAY_F -> asmgen.out("  jsr  floats.func_${function.name}_f_stack")
                 else -> throw AssemblyError("weird type $dt")
             }
         } else {
-            when (dt.typeOrElse(DataType.STRUCT)) {
+            when (dt.typeOrElse(DataType.UNDEFINED)) {
                 DataType.ARRAY_B, DataType.ARRAY_UB, DataType.STR -> asmgen.out("  jsr  prog8_lib.func_${function.name}_b_into_A")
                 DataType.ARRAY_UW, DataType.ARRAY_W -> asmgen.out("  jsr  prog8_lib.func_${function.name}_w_into_A")
                 DataType.ARRAY_F -> asmgen.out("  jsr  floats.func_${function.name}_f_into_A")
@@ -458,7 +632,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
         outputAddressAndLenghtOfArray(fcall.args[0])
         val dt = fcall.args.single().inferType(program)
         if(resultToStack) {
-            when (dt.typeOrElse(DataType.STRUCT)) {
+            when (dt.typeOrElse(DataType.UNDEFINED)) {
                 DataType.ARRAY_UB, DataType.STR -> asmgen.out("  jsr  prog8_lib.func_${function.name}_ub_stack")
                 DataType.ARRAY_B -> asmgen.out("  jsr  prog8_lib.func_${function.name}_b_stack")
                 DataType.ARRAY_UW -> asmgen.out("  jsr  prog8_lib.func_${function.name}_uw_stack")
@@ -467,7 +641,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                 else -> throw AssemblyError("weird type $dt")
             }
         } else {
-            when (dt.typeOrElse(DataType.STRUCT)) {
+            when (dt.typeOrElse(DataType.UNDEFINED)) {
                 DataType.ARRAY_UB, DataType.STR -> {
                     asmgen.out("  jsr  prog8_lib.func_${function.name}_ub_into_A")
                     assignAsmGen.assignRegisterByte(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.A, scope, program, asmgen), CpuRegister.A)
@@ -478,11 +652,11 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                 }
                 DataType.ARRAY_UW -> {
                     asmgen.out("  jsr  prog8_lib.func_${function.name}_uw_into_AY")
-                    assignAsmGen.assignRegisterpairWord(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.A, scope, program, asmgen), RegisterOrPair.AY)
+                    assignAsmGen.assignRegisterpairWord(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.AY, scope, program, asmgen), RegisterOrPair.AY)
                 }
                 DataType.ARRAY_W -> {
                     asmgen.out("  jsr  prog8_lib.func_${function.name}_w_into_AY")
-                    assignAsmGen.assignRegisterpairWord(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.A, scope, program, asmgen), RegisterOrPair.AY)
+                    assignAsmGen.assignRegisterpairWord(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.AY, scope, program, asmgen), RegisterOrPair.AY)
                 }
                 DataType.ARRAY_F -> {
                     asmgen.out("  jsr  floats.func_${function.name}_f_fac1")
@@ -497,7 +671,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
         outputAddressAndLenghtOfArray(fcall.args[0])
         val dt = fcall.args.single().inferType(program)
         if(resultToStack) {
-            when (dt.typeOrElse(DataType.STRUCT)) {
+            when (dt.typeOrElse(DataType.UNDEFINED)) {
                 DataType.ARRAY_UB, DataType.STR -> asmgen.out("  jsr  prog8_lib.func_sum_ub_stack")
                 DataType.ARRAY_B -> asmgen.out("  jsr  prog8_lib.func_sum_b_stack")
                 DataType.ARRAY_UW -> asmgen.out("  jsr  prog8_lib.func_sum_uw_stack")
@@ -506,22 +680,22 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                 else -> throw AssemblyError("weird type $dt")
             }
         } else {
-            when (dt.typeOrElse(DataType.STRUCT)) {
+            when (dt.typeOrElse(DataType.UNDEFINED)) {
                 DataType.ARRAY_UB, DataType.STR -> {
                     asmgen.out("  jsr  prog8_lib.func_sum_ub_into_AY")
-                    assignAsmGen.assignRegisterpairWord(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.A, scope, program, asmgen), RegisterOrPair.AY)
+                    assignAsmGen.assignRegisterpairWord(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.AY, scope, program, asmgen), RegisterOrPair.AY)
                 }
                 DataType.ARRAY_B -> {
                     asmgen.out("  jsr  prog8_lib.func_sum_b_into_AY")
-                    assignAsmGen.assignRegisterpairWord(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.A, scope, program, asmgen), RegisterOrPair.AY)
+                    assignAsmGen.assignRegisterpairWord(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.AY, scope, program, asmgen), RegisterOrPair.AY)
                 }
                 DataType.ARRAY_UW -> {
                     asmgen.out("  jsr  prog8_lib.func_sum_uw_into_AY")
-                    assignAsmGen.assignRegisterpairWord(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.A, scope, program, asmgen), RegisterOrPair.AY)
+                    assignAsmGen.assignRegisterpairWord(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.AY, scope, program, asmgen), RegisterOrPair.AY)
                 }
                 DataType.ARRAY_W -> {
                     asmgen.out("  jsr  prog8_lib.func_sum_w_into_AY")
-                    assignAsmGen.assignRegisterpairWord(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.A, scope, program, asmgen), RegisterOrPair.AY)
+                    assignAsmGen.assignRegisterpairWord(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.AY, scope, program, asmgen), RegisterOrPair.AY)
                 }
                 DataType.ARRAY_F -> {
                     asmgen.out("  jsr  floats.func_sum_f_fac1")
@@ -576,7 +750,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
 
         // optimized simple case: swap two memory locations
         if(first is DirectMemoryRead && second is DirectMemoryRead) {
-            // TODO optimize swap of two memread values with index, using the same pointer expression/variable, like swap(@(ptr+1), @(ptr+2))
+            // TODO optimize swap of two memread values with index, using the same pointer expression/variable, like swap(@(ptr+i1), @(ptr+i2))
             val addr1 = (first.addressExpression as? NumericLiteralValue)?.number?.toHex()
             val addr2 = (second.addressExpression as? NumericLiteralValue)?.number?.toHex()
             val name1 = if(first.addressExpression is IdentifierReference) asmgen.asmVariableName(first.addressExpression as IdentifierReference) else null
@@ -608,12 +782,12 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
             val elementIDt = first.inferType(program)
             if(!elementIDt.isKnown)
                 throw AssemblyError("unknown dt")
-            val elementDt = elementIDt.typeOrElse(DataType.STRUCT)
+            val elementDt = elementIDt.typeOrElse(DataType.UNDEFINED)
 
-            val firstNum = first.indexer.indexNum
-            val firstVar = first.indexer.indexVar
-            val secondNum = second.indexer.indexNum
-            val secondVar = second.indexer.indexVar
+            val firstNum = first.indexer.indexExpr as? NumericLiteralValue
+            val firstVar = first.indexer.indexExpr as? IdentifierReference
+            val secondNum = second.indexer.indexExpr as? NumericLiteralValue
+            val secondVar = second.indexer.indexExpr as? IdentifierReference
 
             if(firstNum!=null && secondNum!=null) {
                 swapArrayValues(elementDt, arrayVarName1, firstNum, arrayVarName2, secondNum)
@@ -641,7 +815,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
             }
         }
 
-        val datatype = first.inferType(program).typeOrElse(DataType.STRUCT)
+        val datatype = first.inferType(program).typeOrElse(DataType.UNDEFINED)
         when(datatype) {
             in ByteDatatypes, in WordDatatypes -> {
                 asmgen.assignExpressionToVariable(first, "P8ZP_SCRATCH_W1", datatype, null)
@@ -912,7 +1086,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
 
     private fun funcAbs(fcall: IFunctionCall, func: FSignature, resultToStack: Boolean, resultRegister: RegisterOrPair?, scope: Subroutine?) {
         translateArguments(fcall.args, func, scope)
-        val dt = fcall.args.single().inferType(program).typeOrElse(DataType.STRUCT)
+        val dt = fcall.args.single().inferType(program).typeOrElse(DataType.UNDEFINED)
         if(resultToStack) {
             when (dt) {
                 in ByteDatatypes -> asmgen.out("  jsr  prog8_lib.abs_b_stack")
@@ -924,15 +1098,15 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
             when (dt) {
                 in ByteDatatypes -> {
                     asmgen.out("  jsr  prog8_lib.abs_b_into_A")
-                    assignAsmGen.assignRegisterByte(AsmAssignTarget.fromRegisters(resultRegister!!, scope, program, asmgen), CpuRegister.A)
+                    assignAsmGen.assignRegisterByte(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.A, scope, program, asmgen), CpuRegister.A)
                 }
                 in WordDatatypes -> {
                     asmgen.out("  jsr  prog8_lib.abs_w_into_AY")
-                    assignAsmGen.assignRegisterpairWord(AsmAssignTarget.fromRegisters(resultRegister!!, scope, program, asmgen), RegisterOrPair.AY)
+                    assignAsmGen.assignRegisterpairWord(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.AY, scope, program, asmgen), RegisterOrPair.AY)
                 }
                 DataType.FLOAT -> {
                     asmgen.out("  jsr  floats.abs_f_fac1")
-                    assignAsmGen.assignRegisterpairWord(AsmAssignTarget.fromRegisters(resultRegister!!, scope, program, asmgen), RegisterOrPair.FAC1)
+                    assignAsmGen.assignFAC1float(AsmAssignTarget.fromRegisters(resultRegister ?: RegisterOrPair.FAC1, scope, program, asmgen))
                 }
                 else -> throw AssemblyError("weird type")
             }
@@ -995,18 +1169,21 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
             }
             is BinaryExpression -> {
                 if(addrExpr.operator=="+" && addrExpr.left is IdentifierReference && addrExpr.right is NumericLiteralValue) {
-                    asmgen.saveRegisterLocal(CpuRegister.X, (fcall as Node).definingSubroutine()!!)
-                    asmgen.assignExpressionToRegister(fcall.args[1], RegisterOrPair.AX)
                     val varname = asmgen.asmVariableName(addrExpr.left as IdentifierReference)
-                    val index = (addrExpr.right as NumericLiteralValue).number.toHex()
-                    asmgen.out("""
-                        ldy  #$index
-                        sta  ($varname),y
-                        txa
-                        iny
-                        sta  ($varname),y""")
-                    asmgen.restoreRegisterLocal(CpuRegister.X)
-                    return
+                    if(asmgen.isZpVar(addrExpr.left as IdentifierReference)) {
+                        // pointervar is already in the zero page, no need to copy
+                        asmgen.saveRegisterLocal(CpuRegister.X, (fcall as Node).definingSubroutine()!!)
+                        asmgen.assignExpressionToRegister(fcall.args[1], RegisterOrPair.AX)
+                        val index = (addrExpr.right as NumericLiteralValue).number.toHex()
+                        asmgen.out("""
+                            ldy  #$index
+                            sta  ($varname),y
+                            txa
+                            iny
+                            sta  ($varname),y""")
+                        asmgen.restoreRegisterLocal(CpuRegister.X)
+                        return
+                    }
                 }
             }
         }
@@ -1050,15 +1227,21 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
             is BinaryExpression -> {
                 if(addrExpr.operator=="+" && addrExpr.left is IdentifierReference && addrExpr.right is NumericLiteralValue) {
                     val varname = asmgen.asmVariableName(addrExpr.left as IdentifierReference)
-                    val index = (addrExpr.right as NumericLiteralValue).number.toHex()
-                    asmgen.out("""
-                        ldy  #$index
-                        lda  ($varname),y
-                        pha
-                        iny
-                        lda  ($varname),y
-                        tay
-                        pla""")
+                    if(asmgen.isZpVar(addrExpr.left as IdentifierReference)) {
+                        // pointervar is already in the zero page, no need to copy
+                        val index = (addrExpr.right as NumericLiteralValue).number.toHex()
+                        asmgen.out("""
+                            ldy  #$index
+                            lda  ($varname),y
+                            pha
+                            iny
+                            lda  ($varname),y
+                            tay
+                            pla""")
+                    }  else {
+                        asmgen.assignExpressionToRegister(fcall.args[0], RegisterOrPair.AY)
+                        asmgen.out("  jsr  prog8_lib.func_peekw")
+                    }
                 } else {
                     asmgen.assignExpressionToRegister(fcall.args[0], RegisterOrPair.AY)
                     asmgen.out("  jsr  prog8_lib.func_peekw")
@@ -1077,7 +1260,10 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                 RegisterOrPair.AY -> {}
                 RegisterOrPair.AX -> asmgen.out("  sty  P8ZP_SCRATCH_REG |  ldx  P8ZP_SCRATCH_REG")
                 RegisterOrPair.XY -> asmgen.out("  tax")
-                in Cx16VirtualRegisters -> asmgen.out("  sta  cx16.${resultRegister.toString().toLowerCase()} |  sty  cx16.${resultRegister.toString().toLowerCase()}+1")
+                in Cx16VirtualRegisters -> asmgen.out(
+                    "  sta  cx16.${
+                        resultRegister.toString().lowercase()
+                    } |  sty  cx16.${resultRegister.toString().lowercase()}+1")
                 else -> throw AssemblyError("invalid reg")
             }
         }
@@ -1127,9 +1313,9 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                 }
                 in Cx16VirtualRegisters -> {
                     asmgen.assignExpressionToRegister(fcall.args[1], RegisterOrPair.A)      // lsb
-                    asmgen.out("  sta  cx16.${reg.toString().toLowerCase()}")
+                    asmgen.out("  sta  cx16.${reg.toString().lowercase()}")
                     asmgen.assignExpressionToRegister(fcall.args[0], RegisterOrPair.A)      // msb
-                    asmgen.out("  sta  cx16.${reg.toString().toLowerCase()}+1")
+                    asmgen.out("  sta  cx16.${reg.toString().lowercase()}+1")
                 }
                 else -> throw AssemblyError("invalid mkword target reg")
             }
@@ -1138,7 +1324,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
 
     private fun funcMsb(fcall: IFunctionCall, resultToStack: Boolean, resultRegister: RegisterOrPair?) {
         val arg = fcall.args.single()
-        if (arg.inferType(program).typeOrElse(DataType.STRUCT) !in WordDatatypes)
+        if (!arg.inferType(program).isWords())
             throw AssemblyError("msb required word argument")
         if (arg is NumericLiteralValue)
             throw AssemblyError("msb(const) should have been const-folded away")
@@ -1182,7 +1368,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
 
     private fun funcLsb(fcall: IFunctionCall, resultToStack: Boolean, resultRegister: RegisterOrPair?) {
         val arg = fcall.args.single()
-        if (arg.inferType(program).typeOrElse(DataType.STRUCT) !in WordDatatypes)
+        if (!arg.inferType(program).isWords())
             throw AssemblyError("lsb required word argument")
         if (arg is NumericLiteralValue)
             throw AssemblyError("lsb(const) should have been const-folded away")
@@ -1246,7 +1432,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
     }
 
     private fun translateArguments(args: MutableList<Expression>, signature: FSignature, scope: Subroutine?) {
-        val callConv = signature.callConvention(args.map { it.inferType(program).typeOrElse(DataType.STRUCT) })
+        val callConv = signature.callConvention(args.map { it.inferType(program).typeOrElse(DataType.UNDEFINED) })
 
         fun getSourceForFloat(value: Expression): AsmAssignSource {
             return when (value) {

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

@@ -1,7 +1,7 @@
-package prog8.compiler.target.c64.codegen
+package prog8.compiler.target.cpu6502.codegen
 
 import prog8.ast.Program
-import prog8.ast.base.ArrayElementTypes
+import prog8.ast.base.ArrayToElementTypes
 import prog8.ast.base.DataType
 import prog8.ast.base.RegisterOrPair
 import prog8.ast.expressions.IdentifierReference
@@ -21,13 +21,13 @@ internal class ForLoopsAsmGen(private val program: Program, private val asmgen:
             is RangeExpr -> {
                 val range = (stmt.iterable as RangeExpr).toConstantIntegerRange()
                 if(range==null) {
-                    translateForOverNonconstRange(stmt, iterableDt.typeOrElse(DataType.STRUCT), stmt.iterable as RangeExpr)
+                    translateForOverNonconstRange(stmt, iterableDt.typeOrElse(DataType.UNDEFINED), stmt.iterable as RangeExpr)
                 } else {
-                    translateForOverConstRange(stmt, iterableDt.typeOrElse(DataType.STRUCT), range)
+                    translateForOverConstRange(stmt, iterableDt.typeOrElse(DataType.UNDEFINED), range)
                 }
             }
             is IdentifierReference -> {
-                translateForOverIterableVar(stmt, iterableDt.typeOrElse(DataType.STRUCT), stmt.iterable as IdentifierReference)
+                translateForOverIterableVar(stmt, iterableDt.typeOrElse(DataType.UNDEFINED), stmt.iterable as IdentifierReference)
             }
             else -> throw AssemblyError("can't iterate over ${stmt.iterable.javaClass} - should have been replaced by a variable")
         }
@@ -40,6 +40,13 @@ internal class ForLoopsAsmGen(private val program: Program, private val asmgen:
         val modifiedLabel2 = asmgen.makeLabel("for_modifiedb")
         asmgen.loopEndLabels.push(endLabel)
         val stepsize=range.step.constValue(program)!!.number.toInt()
+
+        if(stepsize < -1) {
+            val limit = range.to.constValue(program)?.number?.toDouble()
+            if(limit==0.0)
+                throw AssemblyError("for unsigned loop variable it's not possible to count down with step != -1 from a non-const value to exactly zero due to value wrapping")
+        }
+
         when(iterableDt) {
             DataType.ARRAY_B, DataType.ARRAY_UB -> {
                 if (stepsize==1 || stepsize==-1) {
@@ -49,17 +56,17 @@ internal class ForLoopsAsmGen(private val program: Program, private val asmgen:
                     val incdec = if(stepsize==1) "inc" else "dec"
                     // loop over byte range via loopvar
                     val varname = asmgen.asmVariableName(stmt.loopVar)
-                    asmgen.assignExpressionToVariable(range.from, varname, ArrayElementTypes.getValue(iterableDt), null)
-                    asmgen.assignExpressionToVariable(range.to, "$modifiedLabel+1", ArrayElementTypes.getValue(iterableDt), null)
+                    asmgen.assignExpressionToVariable(range.from, varname, ArrayToElementTypes.getValue(iterableDt), null)
+                    asmgen.assignExpressionToVariable(range.to, "$modifiedLabel+1", ArrayToElementTypes.getValue(iterableDt), null)
                     asmgen.out(loopLabel)
                     asmgen.translate(stmt.body)
                     asmgen.out("""
                         lda  $varname
 $modifiedLabel          cmp  #0         ; modified 
                         beq  $endLabel
-                        $incdec  $varname
-                        jmp  $loopLabel
-$endLabel""")
+                        $incdec  $varname""")
+                    asmgen.jmp(loopLabel)
+                    asmgen.out(endLabel)
 
                 } else {
 
@@ -67,8 +74,8 @@ $endLabel""")
 
                     // loop over byte range via loopvar
                     val varname = asmgen.asmVariableName(stmt.loopVar)
-                    asmgen.assignExpressionToVariable(range.from, varname, ArrayElementTypes.getValue(iterableDt), null)
-                    asmgen.assignExpressionToVariable(range.to, "$modifiedLabel+1", ArrayElementTypes.getValue(iterableDt), null)
+                    asmgen.assignExpressionToVariable(range.from, varname, ArrayToElementTypes.getValue(iterableDt), null)
+                    asmgen.assignExpressionToVariable(range.to, "$modifiedLabel+1", ArrayToElementTypes.getValue(iterableDt), null)
                     asmgen.out(loopLabel)
                     asmgen.translate(stmt.body)
                     if(stepsize>0) {
@@ -117,16 +124,15 @@ $modifiedLabel2 cmp  #0    ; modified
                             asmgen.out("""
 +               inc  $varname
                 bne  $loopLabel
-                inc  $varname+1
-                jmp  $loopLabel
-                            """)
+                inc  $varname+1""")
+                            asmgen.jmp(loopLabel)
                         } else {
                             asmgen.out("""
 +               lda  $varname
                 bne  +
                 dec  $varname+1
-+               dec  $varname
-                jmp  $loopLabel""")
++               dec  $varname""")
+                            asmgen.jmp(loopLabel)
                         }
                         asmgen.out(endLabel)
                     }
@@ -282,7 +288,7 @@ $loopLabel          sty  $indexVar
                         bne  $loopLabel
                         beq  $endLabel""")
                 }
-                if(length>=16 && asmgen.zeropage.available() > 0) {
+                if(length>=16 && asmgen.zeropage.hasByteAvailable()) {
                     // allocate index var on ZP
                     val zpAddr = asmgen.zeropage.allocate(indexVar, DataType.UBYTE, stmt.position, asmgen.errors)
                     asmgen.out("""$indexVar = $zpAddr  ; auto zp UBYTE""")
@@ -321,7 +327,7 @@ $loopLabel          sty  $indexVar
                         bne  $loopLabel
                         beq  $endLabel""")
                 }
-                if(length>=16 && asmgen.zeropage.available() > 0) {
+                if(length>=16 && asmgen.zeropage.hasByteAvailable()) {
                     // allocate index var on ZP
                     val zpAddr = asmgen.zeropage.allocate(indexVar, DataType.UBYTE, stmt.position, asmgen.errors)
                     asmgen.out("""$indexVar = $zpAddr  ; auto zp UBYTE""")
@@ -386,23 +392,25 @@ $loopLabel""")
                     }
                     -2 -> {
                         when (range.last) {
-                            0 -> asmgen.out("""
-                                lda  $varname
-                                beq  $endLabel
-                                dec  $varname
-                                dec  $varname
-                                jmp  $loopLabel""")
+                            0 -> {
+                                asmgen.out("""
+                                    lda  $varname
+                                    beq  $endLabel
+                                    dec  $varname
+                                    dec  $varname""")
+                                asmgen.jmp(loopLabel)
+                            }
                             1 -> asmgen.out("""
-                                dec  $varname
-                                beq  $endLabel
-                                dec  $varname
-                                bne  $loopLabel""")
+                                    dec  $varname
+                                    beq  $endLabel
+                                    dec  $varname
+                                    bne  $loopLabel""")
                             else -> asmgen.out("""
-                                dec  $varname
-                                dec  $varname
-                                lda  $varname
-                                cmp  #${range.last-2}
-                                bne  $loopLabel""")
+                                    dec  $varname
+                                    dec  $varname
+                                    lda  $varname
+                                    cmp  #${range.last-2}
+                                    bne  $loopLabel""")
                         }
                     }
                     else -> {
@@ -413,8 +421,8 @@ $loopLabel""")
                             beq  $endLabel
                             clc
                             adc  #${range.step}
-                            sta  $varname
-                            jmp  $loopLabel""")
+                            sta  $varname""")
+                        asmgen.jmp(loopLabel)
                     }
                 }
                 asmgen.out(endLabel)
@@ -450,9 +458,9 @@ $loopLabel""")
                             sta  $varname
                             lda  $varname+1
                             adc  #>${range.step}
-                            sta  $varname+1
-                            jmp  $loopLabel
-$endLabel""")
+                            sta  $varname+1""")
+                        asmgen.jmp(loopLabel)
+                        asmgen.out(endLabel)
                     }
                 }
             }
@@ -502,9 +510,9 @@ $loopLabel""")
                 asmgen.out("""
                     lda  $varname
                     beq  $endLabel
-                    dec  $varname
-                    jmp  $loopLabel
-$endLabel""")
+                    dec  $varname""")
+                asmgen.jmp(loopLabel)
+                asmgen.out(endLabel)
             }
             1 -> {
                 asmgen.out("""
@@ -545,9 +553,9 @@ $loopLabel""")
             beq  $endLabel
 +           inc  $varname
             bne  $loopLabel
-            inc  $varname+1
-            jmp  $loopLabel
-$endLabel""")
+            inc  $varname+1""")
+        asmgen.jmp(loopLabel)
+        asmgen.out(endLabel)
         asmgen.loopEndLabels.pop()
     }
 
@@ -573,12 +581,12 @@ $loopLabel""")
 +           lda  $varname
             bne  +
             dec  $varname+1
-+           dec  $varname
-            jmp  $loopLabel
-$endLabel""")
++           dec  $varname""")
+        asmgen.jmp(loopLabel)
+        asmgen.out(endLabel)
         asmgen.loopEndLabels.pop()
     }
 
     private fun assignLoopvar(stmt: ForLoop, range: RangeExpr) =
-        asmgen.assignExpressionToVariable(range.from, asmgen.asmVariableName(stmt.loopVar), stmt.loopVarDt(program).typeOrElse(DataType.STRUCT), stmt.definingSubroutine())
+        asmgen.assignExpressionToVariable(range.from, asmgen.asmVariableName(stmt.loopVar), stmt.loopVarDt(program).typeOrElse(DataType.UNDEFINED), stmt.definingSubroutine())
 }

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

@@ -1,4 +1,4 @@
-package prog8.compiler.target.c64.codegen
+package prog8.compiler.target.cpu6502.codegen
 
 import prog8.ast.IFunctionCall
 import prog8.ast.Node
@@ -8,10 +8,10 @@ import prog8.ast.expressions.*
 import prog8.ast.statements.*
 import prog8.compiler.AssemblyError
 import prog8.compiler.target.CpuType
-import prog8.compiler.target.c64.codegen.assignment.AsmAssignSource
-import prog8.compiler.target.c64.codegen.assignment.AsmAssignTarget
-import prog8.compiler.target.c64.codegen.assignment.AsmAssignment
-import prog8.compiler.target.c64.codegen.assignment.TargetStorageKind
+import prog8.compiler.target.cpu6502.codegen.assignment.AsmAssignSource
+import prog8.compiler.target.cpu6502.codegen.assignment.AsmAssignTarget
+import prog8.compiler.target.cpu6502.codegen.assignment.AsmAssignment
+import prog8.compiler.target.cpu6502.codegen.assignment.TargetStorageKind
 
 
 internal class FunctionCallAsmGen(private val program: Program, private val asmgen: AsmGen) {
@@ -111,17 +111,24 @@ internal class FunctionCallAsmGen(private val program: Program, private val asmg
             }
         }
 
-        if(sub.inline && asmgen.options.optimize) {
-            if(sub.containsDefinedVariables())
-                throw AssemblyError("can't inline sub with vars")
-            if(!sub.isAsmSubroutine && sub.parameters.isNotEmpty())
-                throw AssemblyError("can't inline a non-asm subroutine with parameters")
-            asmgen.out("  \t; inlined routine follows: ${sub.name} from ${sub.position}")
-            val statements = sub.statements.filter { it !is ParameterVarDecl && it !is Directive }
-            statements.forEach { asmgen.translate(it) }
-        }
-        else {
+        if(!sub.inline || !asmgen.options.optimize) {
             asmgen.out("  jsr  $subName")
+        } else {
+            // inline the subroutine.
+            // we do this by copying the subroutine's statements at the call site.
+            // NOTE: *if* there is a return statement, it will be the only one, and the very last statement of the subroutine
+            // (this condition has been enforced by an ast check earlier)
+            asmgen.out("  \t; inlined routine follows: ${sub.name}")
+            val statements = sub.statements.filter { it !is ParameterVarDecl && it !is Directive }
+            statements.forEach {
+                if(it is Return) {
+                    asmgen.translate(it, false)     // don't use RTS for the inlined return statement
+                } else {
+                    if(!sub.inline || it !is VarDecl)
+                        asmgen.translate(it)
+                }
+            }
+            asmgen.out("  \t; inlined routine end: ${sub.name}")
         }
 
         // remember: dealing with the X register and/or dealing with return values is the responsibility of the caller
@@ -168,21 +175,31 @@ internal class FunctionCallAsmGen(private val program: Program, private val asmg
                     when (sub.parameters[argi.index].type) {
                         in ByteDatatypes -> {
                             // only load the lsb of the virtual register
-                            asmgen.out("""
+                            asmgen.out(
+                                """
                                 lda  P8ESTACK_LO$plusIdxStr,x
-                                sta  cx16.${argi.value.second.registerOrPair.toString().toLowerCase()}
+                                sta  cx16.${argi.value.second.registerOrPair.toString().lowercase()}
                             """)
                             if (asmgen.isTargetCpu(CpuType.CPU65c02))
-                                asmgen.out("  stz  cx16.${argi.value.second.registerOrPair.toString().toLowerCase()}+1")
+                                asmgen.out(
+                                    "  stz  cx16.${
+                                        argi.value.second.registerOrPair.toString().lowercase()
+                                    }+1")
                             else
-                                asmgen.out("  lda  #0 |  sta  cx16.${argi.value.second.registerOrPair.toString().toLowerCase()}+1")
+                                asmgen.out(
+                                    "  lda  #0 |  sta  cx16.${
+                                        argi.value.second.registerOrPair.toString().lowercase()
+                                    }+1")
                         }
-                        in WordDatatypes ->
-                            asmgen.out("""
+                        in WordDatatypes, in IterableDatatypes ->
+                            asmgen.out(
+                                """
                                 lda  P8ESTACK_LO$plusIdxStr,x
-                                sta  cx16.${argi.value.second.registerOrPair.toString().toLowerCase()}
+                                sta  cx16.${argi.value.second.registerOrPair.toString().lowercase()}
                                 lda  P8ESTACK_HI$plusIdxStr,x
-                                sta  cx16.${argi.value.second.registerOrPair.toString().toLowerCase()}+1
+                                sta  cx16.${
+                                    argi.value.second.registerOrPair.toString().lowercase()
+                                }+1
                             """)
                         else -> throw AssemblyError("weird dt")
                     }
@@ -237,7 +254,7 @@ internal class FunctionCallAsmGen(private val program: Program, private val asmg
         val valueIDt = value.inferType(program)
         if(!valueIDt.isKnown)
             throw AssemblyError("unknown dt")
-        val valueDt = valueIDt.typeOrElse(DataType.STRUCT)
+        val valueDt = valueIDt.typeOrElse(DataType.UNDEFINED)
         if(!isArgumentTypeCompatible(valueDt, parameter.value.type))
             throw AssemblyError("argument type incompatible")
 
@@ -250,7 +267,7 @@ internal class FunctionCallAsmGen(private val program: Program, private val asmg
         val valueIDt = value.inferType(program)
         if(!valueIDt.isKnown)
             throw AssemblyError("unknown dt")
-        val valueDt = valueIDt.typeOrElse(DataType.STRUCT)
+        val valueDt = valueIDt.typeOrElse(DataType.UNDEFINED)
         if(!isArgumentTypeCompatible(valueDt, parameter.value.type))
             throw AssemblyError("argument type incompatible")
 

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

@@ -1,4 +1,4 @@
-package prog8.compiler.target.c64.codegen
+package prog8.compiler.target.cpu6502.codegen
 
 import prog8.ast.Program
 import prog8.ast.base.*
@@ -19,7 +19,7 @@ internal class PostIncrDecrAsmGen(private val program: Program, private val asmg
         when {
             targetIdent!=null -> {
                 val what = asmgen.asmVariableName(targetIdent)
-                when (stmt.target.inferType(program).typeOrElse(DataType.STRUCT)) {
+                when (stmt.target.inferType(program).typeOrElse(DataType.UNDEFINED)) {
                     in ByteDatatypes -> asmgen.out(if (incr) "  inc  $what" else "  dec  $what")
                     in WordDatatypes -> {
                         if(incr)
@@ -65,9 +65,10 @@ internal class PostIncrDecrAsmGen(private val program: Program, private val asmg
             }
             targetArrayIdx!=null -> {
                 val asmArrayvarname = asmgen.asmVariableName(targetArrayIdx.arrayvar)
-                val elementDt = targetArrayIdx.inferType(program).typeOrElse(DataType.STRUCT)
-                if(targetArrayIdx.indexer.indexNum!=null) {
-                    val indexValue = targetArrayIdx.indexer.constIndex()!! * program.memsizer.memorySize(elementDt)
+                val elementDt = targetArrayIdx.inferType(program).typeOrElse(DataType.UNDEFINED)
+                val constIndex = targetArrayIdx.indexer.constIndex()
+                if(constIndex!=null) {
+                    val indexValue = constIndex * program.memsizer.memorySize(elementDt)
                     when(elementDt) {
                         in ByteDatatypes -> asmgen.out(if (incr) "  inc  $asmArrayvarname+$indexValue" else "  dec  $asmArrayvarname+$indexValue")
                         in WordDatatypes -> {

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

@@ -1,4 +1,4 @@
-package prog8.compiler.target.c64.codegen.assignment
+package prog8.compiler.target.cpu6502.codegen.assignment
 
 import prog8.ast.IMemSizer
 import prog8.ast.Program
@@ -6,7 +6,7 @@ import prog8.ast.base.*
 import prog8.ast.expressions.*
 import prog8.ast.statements.*
 import prog8.compiler.AssemblyError
-import prog8.compiler.target.c64.codegen.AsmGen
+import prog8.compiler.target.cpu6502.codegen.AsmGen
 
 
 internal enum class TargetStorageKind {
@@ -59,7 +59,7 @@ internal class AsmAssignTarget(val kind: TargetStorageKind,
             val idt = inferType(program)
             if(!idt.isKnown)
                 throw AssemblyError("unknown dt")
-            val dt = idt.typeOrElse(DataType.STRUCT)
+            val dt = idt.typeOrElse(DataType.UNDEFINED)
             when {
                 identifier != null -> AsmAssignTarget(TargetStorageKind.VARIABLE, program, asmgen, dt, assign.definingSubroutine(), variableAsmName = asmgen.asmVariableName(identifier!!), origAstTarget =  this)
                 arrayindexed != null -> AsmAssignTarget(TargetStorageKind.ARRAY, program, asmgen, dt, assign.definingSubroutine(), array = arrayindexed, origAstTarget =  this)
@@ -120,13 +120,7 @@ internal class AsmAssignSource(val kind: SourceStorageKind,
             asmgen.asmVariableName(array.arrayvar)
 
     companion object {
-        fun fromAstSource(indexer: ArrayIndex, program: Program, asmgen: AsmGen): AsmAssignSource {
-            return when {
-                indexer.indexNum!=null -> fromAstSource(indexer.indexNum!!, program, asmgen)
-                indexer.indexVar!=null -> fromAstSource(indexer.indexVar!!, program, asmgen)
-                else -> throw AssemblyError("weird indexer")
-            }
-        }
+        fun fromAstSource(indexer: ArrayIndex, program: Program, asmgen: AsmGen): AsmAssignSource = fromAstSource(indexer.indexExpr, program, asmgen)
 
         fun fromAstSource(value: Expression, program: Program, asmgen: AsmGen): AsmAssignSource {
             val cv = value.constValue(program)
@@ -138,12 +132,12 @@ internal class AsmAssignSource(val kind: SourceStorageKind,
                 is StringLiteralValue -> throw AssemblyError("string literal value should not occur anymore for asm generation")
                 is ArrayLiteralValue -> throw AssemblyError("array literal value should not occur anymore for asm generation")
                 is IdentifierReference -> {
-                    val dt = value.inferType(program).typeOrElse(DataType.STRUCT)
+                    val dt = value.inferType(program).typeOrElse(DataType.UNDEFINED)
                     val varName=asmgen.asmVariableName(value)
                     // special case: "cx16.r[0-15]" are 16-bits virtual registers of the commander X16 system
-                    if(dt==DataType.UWORD && varName.toLowerCase().startsWith("cx16.r")) {
-                        val regStr = varName.toLowerCase().substring(5)
-                        val reg = RegisterOrPair.valueOf(regStr.toUpperCase())
+                    if(dt == DataType.UWORD && varName.lowercase().startsWith("cx16.r")) {
+                        val regStr = varName.lowercase().substring(5)
+                        val reg = RegisterOrPair.valueOf(regStr.uppercase())
                         AsmAssignSource(SourceStorageKind.REGISTER, program, asmgen, dt, register = reg)
                     } else {
                         AsmAssignSource(SourceStorageKind.VARIABLE, program, asmgen, dt, variableAsmName = varName)
@@ -153,7 +147,7 @@ internal class AsmAssignSource(val kind: SourceStorageKind,
                     AsmAssignSource(SourceStorageKind.MEMORY, program, asmgen, DataType.UBYTE, memory = value)
                 }
                 is ArrayIndexedExpression -> {
-                    val dt = value.inferType(program).typeOrElse(DataType.STRUCT)
+                    val dt = value.inferType(program).typeOrElse(DataType.UNDEFINED)
                     AsmAssignSource(SourceStorageKind.ARRAY, program, asmgen, dt, array = value)
                 }
                 is FunctionCall -> {
@@ -168,7 +162,7 @@ internal class AsmAssignSource(val kind: SourceStorageKind,
                             val returnType = value.inferType(program)
                             if(!returnType.isKnown)
                                 throw AssemblyError("unknown dt")
-                            AsmAssignSource(SourceStorageKind.EXPRESSION, program, asmgen, returnType.typeOrElse(DataType.STRUCT), expression = value)
+                            AsmAssignSource(SourceStorageKind.EXPRESSION, program, asmgen, returnType.typeOrElse(DataType.UNDEFINED), expression = value)
                         }
                         else -> {
                             throw AssemblyError("weird call")
@@ -179,7 +173,7 @@ internal class AsmAssignSource(val kind: SourceStorageKind,
                     val dt = value.inferType(program)
                     if(!dt.isKnown)
                         throw AssemblyError("unknown dt")
-                    AsmAssignSource(SourceStorageKind.EXPRESSION, program, asmgen, dt.typeOrElse(DataType.STRUCT), expression = value)
+                    AsmAssignSource(SourceStorageKind.EXPRESSION, program, asmgen, dt.typeOrElse(DataType.UNDEFINED), expression = value)
                 }
             }
         }
@@ -212,7 +206,7 @@ internal class AsmAssignment(val source: AsmAssignSource,
 
     init {
         if(target.register !in setOf(RegisterOrPair.XY, RegisterOrPair.AX, RegisterOrPair.AY))
-            require(source.datatype != DataType.STRUCT) { "must not be placeholder datatype" }
+            require(source.datatype != DataType.UNDEFINED) { "must not be placeholder/undefined datatype" }
             require(memsizer.memorySize(source.datatype) <= memsizer.memorySize(target.datatype)) {
                 "source storage size must be less or equal to target datatype storage size"
             }

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

@@ -1,4 +1,4 @@
-package prog8.compiler.target.c64.codegen.assignment
+package prog8.compiler.target.cpu6502.codegen.assignment
 
 import prog8.ast.Program
 import prog8.ast.base.*
@@ -9,12 +9,13 @@ import prog8.compiler.AssemblyError
 import prog8.compiler.functions.BuiltinFunctions
 import prog8.compiler.functions.builtinFunctionReturnType
 import prog8.compiler.target.CpuType
-import prog8.compiler.target.c64.codegen.AsmGen
-import prog8.compiler.target.c64.codegen.ExpressionsAsmGen
+import prog8.compiler.target.cpu6502.codegen.AsmGen
+import prog8.compiler.target.cpu6502.codegen.ExpressionsAsmGen
 
 
 internal class AssignmentAsmGen(private val program: Program, private val asmgen: AsmGen,
-                                private val exprAsmgen: ExpressionsAsmGen) {
+                                private val exprAsmgen: ExpressionsAsmGen
+) {
 
     private val augmentableAsmGen = AugmentableAssignmentAsmGen(program, this, exprAsmgen, asmgen)
 
@@ -64,9 +65,10 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                 val value = assign.source.array!!
                 val elementDt = assign.source.datatype
                 val arrayVarName = asmgen.asmVariableName(value.arrayvar)
-                if (value.indexer.indexNum!=null) {
+                val constIndex = value.indexer.constIndex()
+                if (constIndex!=null) {
                     // constant array index value
-                    val indexValue = value.indexer.constIndex()!! * program.memsizer.memorySize(elementDt)
+                    val indexValue = constIndex * program.memsizer.memorySize(elementDt)
                     when (elementDt) {
                         in ByteDatatypes -> {
                             asmgen.out("  lda  $arrayVarName+$indexValue")
@@ -143,7 +145,7 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
             SourceStorageKind.EXPRESSION -> {
                 when(val value = assign.source.expression!!) {
                     is AddressOf -> {
-                        val sourceName = value.identifier.firstStructVarName(program) ?: asmgen.asmVariableName(value.identifier)
+                        val sourceName = asmgen.asmSymbolName(value.identifier)
                         assignAddressOf(assign.target, sourceName)
                     }
                     is NumericLiteralValue -> throw AssemblyError("source kind should have been literalnumber")
@@ -215,7 +217,7 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                                     val returntype = builtinFunctionReturnType(sub.name, value.args, program)
                                     if(!returntype.isKnown)
                                         throw AssemblyError("unknown dt")
-                                    when(returntype.typeOrElse(DataType.STRUCT)) {
+                                    when(returntype.typeOrElse(DataType.UNDEFINED)) {
                                         in ByteDatatypes -> assignRegisterByte(assign.target, CpuRegister.A)            // function's byte result is in A
                                         in WordDatatypes -> assignRegisterpairWord(assign.target, RegisterOrPair.AY)    // function's word result is in AY
                                         DataType.STR -> {
@@ -297,7 +299,7 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
         val valueIDt = value.inferType(program)
         if(!valueIDt.isKnown)
             throw AssemblyError("unknown dt")
-        val valueDt = valueIDt.typeOrElse(DataType.STRUCT)
+        val valueDt = valueIDt.typeOrElse(DataType.UNDEFINED)
         if(valueDt==targetDt)
             throw AssemblyError("type cast to identical dt should have been removed")
 
@@ -356,8 +358,8 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
 
 
         // special case optimizations
-        if(target.kind==TargetStorageKind.VARIABLE) {
-            if(value is IdentifierReference && valueDt != DataType.STRUCT)
+        if(target.kind== TargetStorageKind.VARIABLE) {
+            if(value is IdentifierReference && valueDt != DataType.UNDEFINED)
                 return assignTypeCastedIdentifier(target.asmVarname, targetDt, asmgen.asmVariableName(value), valueDt)
 
             when (valueDt) {
@@ -429,8 +431,8 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
         }
 
         // give up, do it via eval stack
-        // TODO optimize typecasts for more special cases?
         // note: cannot use assignTypeCastedValue because that is ourselves :P
+        // TODO optimize typecasts for more special cases?
         if(this.asmgen.options.slowCodegenWarnings)
             println("warning: slow stack evaluation used for typecast: $value into $targetDt (target=${target.kind} at ${value.position}")
         asmgen.translateExpression(origTypeCastExpression)      // this performs the actual type cast in translateExpression(Typecast)
@@ -569,11 +571,7 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                     else -> throw AssemblyError("weird type")
                 }
             }
-            DataType.STR -> {
-                if (targetDt != DataType.UWORD && targetDt == DataType.STR)
-                    throw AssemblyError("cannot typecast a string into another incompatitble type")
-                TODO("assign typecasted string into target var")
-            }
+            DataType.STR -> throw AssemblyError("cannot typecast a string value")
             else -> throw AssemblyError("weird type")
         }
     }
@@ -589,13 +587,19 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
             DataType.UBYTE -> {
                 when(targetDt) {
                     DataType.UBYTE, DataType.BYTE -> {
-                        asmgen.out("  st${regs.toString().toLowerCase()}  $targetAsmVarName")
+                        asmgen.out("  st${regs.toString().lowercase()}  $targetAsmVarName")
                     }
                     DataType.UWORD, DataType.WORD -> {
                         if(asmgen.isTargetCpu(CpuType.CPU65c02))
-                            asmgen.out("  st${regs.toString().toLowerCase()}  $targetAsmVarName |  stz  $targetAsmVarName+1")
+                            asmgen.out(
+                                "  st${
+                                    regs.toString().lowercase()
+                                }  $targetAsmVarName |  stz  $targetAsmVarName+1")
                         else
-                            asmgen.out("  st${regs.toString().toLowerCase()}  $targetAsmVarName |  lda  #0  |  sta  $targetAsmVarName+1")
+                            asmgen.out(
+                                "  st${
+                                    regs.toString().lowercase()
+                                }  $targetAsmVarName |  lda  #0  |  sta  $targetAsmVarName+1")
                     }
                     DataType.FLOAT -> {
                         when(regs) {
@@ -617,13 +621,19 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
             DataType.BYTE -> {
                 when(targetDt) {
                     DataType.UBYTE, DataType.BYTE -> {
-                        asmgen.out("  st${regs.toString().toLowerCase()}  $targetAsmVarName")
+                        asmgen.out("  st${regs.toString().lowercase()}  $targetAsmVarName")
                     }
                     DataType.UWORD -> {
                         if(asmgen.isTargetCpu(CpuType.CPU65c02))
-                            asmgen.out("  st${regs.toString().toLowerCase()}  $targetAsmVarName |  stz  $targetAsmVarName+1")
+                            asmgen.out(
+                                "  st${
+                                    regs.toString().lowercase()
+                                }  $targetAsmVarName |  stz  $targetAsmVarName+1")
                         else
-                            asmgen.out("  st${regs.toString().toLowerCase()}  $targetAsmVarName |  lda  #0  |  sta  $targetAsmVarName+1")
+                            asmgen.out(
+                                "  st${
+                                    regs.toString().lowercase()
+                                }  $targetAsmVarName |  lda  #0  |  sta  $targetAsmVarName+1")
                     }
                     DataType.WORD -> {
                         when(regs) {
@@ -655,7 +665,7 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
             DataType.UWORD -> {
                 when(targetDt) {
                     DataType.BYTE, DataType.UBYTE -> {
-                        asmgen.out("  st${regs.toString().toLowerCase().first()}  $targetAsmVarName")
+                        asmgen.out("  st${regs.toString().lowercase().first()}  $targetAsmVarName")
                     }
                     DataType.WORD, DataType.UWORD -> {
                         when(regs) {
@@ -683,7 +693,7 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
             DataType.WORD -> {
                 when(targetDt) {
                     DataType.BYTE, DataType.UBYTE -> {
-                        asmgen.out("  st${regs.toString().toLowerCase().first()}  $targetAsmVarName")
+                        asmgen.out("  st${regs.toString().lowercase().first()}  $targetAsmVarName")
                     }
                     DataType.WORD, DataType.UWORD -> {
                         when(regs) {
@@ -708,11 +718,7 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                     else -> throw AssemblyError("weird type")
                 }
             }
-            DataType.STR -> {
-                if (targetDt != DataType.UWORD && targetDt == DataType.STR)
-                    throw AssemblyError("cannot typecast a string into another incompatitble type")
-                TODO("assign typecasted string into target var")
-            }
+            DataType.STR -> throw AssemblyError("cannot typecast a string value")
             else -> throw AssemblyError("weird type")
         }
     }
@@ -828,12 +834,13 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                             RegisterOrPair.AX -> asmgen.out(" inx |  txy |  ldx  #0 |  lda  P8ESTACK_LO,y")
                             RegisterOrPair.AY -> asmgen.out(" inx |  ldy  #0 |  lda  P8ESTACK_LO,x")
                             in Cx16VirtualRegisters -> {
-                                asmgen.out("""
+                                asmgen.out(
+                                    """
                                     inx
                                     lda  P8ESTACK_LO,x
-                                    sta  cx16.${target.register.toString().toLowerCase()}
+                                    sta  cx16.${target.register.toString().lowercase()}
                                     lda  #0
-                                    sta  cx16.${target.register.toString().toLowerCase()}+1
+                                    sta  cx16.${target.register.toString().lowercase()}+1
                                 """)
                             }
                             else -> throw AssemblyError("can't assign byte from stack to register pair XY")
@@ -845,12 +852,13 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                             RegisterOrPair.AY-> asmgen.out(" inx |  ldy  P8ESTACK_HI,x |  lda  P8ESTACK_LO,x")
                             RegisterOrPair.XY-> throw AssemblyError("can't load X from stack here - use intermediary var? ${target.origAstTarget?.position}")
                             in Cx16VirtualRegisters -> {
-                                asmgen.out("""
+                                asmgen.out(
+                                    """
                                     inx
                                     lda  P8ESTACK_LO,x
-                                    sta  cx16.${target.register.toString().toLowerCase()}
+                                    sta  cx16.${target.register.toString().lowercase()}
                                     lda  P8ESTACK_HI,x
-                                    sta  cx16.${target.register.toString().toLowerCase()}+1
+                                    sta  cx16.${target.register.toString().lowercase()}+1
                                 """)
                             }
                             else -> throw AssemblyError("can't assign word to single byte register")
@@ -894,11 +902,12 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                     RegisterOrPair.AY -> asmgen.out("  ldy  #>$sourceName |  lda  #<$sourceName")
                     RegisterOrPair.XY -> asmgen.out("  ldy  #>$sourceName |  ldx  #<$sourceName")
                     in Cx16VirtualRegisters -> {
-                        asmgen.out("""
+                        asmgen.out(
+                            """
                             lda  #<$sourceName
-                            sta  cx16.${target.register.toString().toLowerCase()}
+                            sta  cx16.${target.register.toString().lowercase()}
                             lda  #>$sourceName
-                            sta  cx16.${target.register.toString().toLowerCase()}+1
+                            sta  cx16.${target.register.toString().lowercase()}+1
                         """)
                     }
                     else -> throw AssemblyError("can't load address in a single 8-bit register")
@@ -1035,11 +1044,12 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                     RegisterOrPair.AY -> asmgen.out("  ldy  $sourceName+1 |  lda  $sourceName")
                     RegisterOrPair.XY -> asmgen.out("  ldy  $sourceName+1 |  ldx  $sourceName")
                     in Cx16VirtualRegisters -> {
-                        asmgen.out("""
+                        asmgen.out(
+                            """
                             lda  $sourceName
-                            sta  cx16.${target.register.toString().toLowerCase()}
+                            sta  cx16.${target.register.toString().lowercase()}
                             lda  $sourceName+1
-                            sta  cx16.${target.register.toString().toLowerCase()}+1
+                            sta  cx16.${target.register.toString().lowercase()}+1
                         """)
                     }
                     else -> throw AssemblyError("can't load word in a single 8-bit register")
@@ -1073,11 +1083,11 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                     ldy  #>${target.asmVarname}
                     sta  P8ZP_SCRATCH_W1
                     sty  P8ZP_SCRATCH_W1+1""")
-                if(target.array!!.indexer.indexNum!=null) {
-                    val index = target.array.indexer.constIndex()!!
-                    asmgen.out(" lda  #$index")
+                val constIndex = target.array!!.indexer.constIndex()
+                if(constIndex!=null) {
+                    asmgen.out(" lda  #$constIndex")
                 } else {
-                    val asmvarname = asmgen.asmVariableName(target.array.indexer.indexVar!!)
+                    val asmvarname = asmgen.asmVariableName(target.array.indexer.indexExpr as IdentifierReference)
                     asmgen.out(" lda  $asmvarname")
                 }
                 asmgen.out("  jsr  floats.set_array_float_from_fac1")
@@ -1109,11 +1119,11 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                     ldy  #>${target.asmVarname}
                     sta  P8ZP_SCRATCH_W2
                     sty  P8ZP_SCRATCH_W2+1""")
-                if(target.array!!.indexer.indexNum!=null) {
-                    val index = target.array.indexer.constIndex()!!
-                    asmgen.out(" lda  #$index")
+                val constIndex = target.array!!.indexer.constIndex()
+                if(constIndex!=null) {
+                    asmgen.out(" lda  #$constIndex")
                 } else {
-                    val asmvarname = asmgen.asmVariableName(target.array.indexer.indexVar!!)
+                    val asmvarname = asmgen.asmVariableName(target.array.indexer.indexExpr as IdentifierReference)
                     asmgen.out(" lda  $asmvarname")
                 }
                 asmgen.out(" jsr  floats.set_array_float")
@@ -1156,11 +1166,11 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                     ldy  #>${target.asmVarname}
                     sta  P8ZP_SCRATCH_W2
                     sty  P8ZP_SCRATCH_W2+1""")
-                if(target.array!!.indexer.indexNum!=null) {
-                    val index = target.array.indexer.constIndex()!!
-                    asmgen.out(" lda  #$index")
+                val constIndex = target.array!!.indexer.constIndex()
+                if(constIndex!=null) {
+                    asmgen.out(" lda  #$constIndex")
                 } else {
-                    val asmvarname = asmgen.asmVariableName(target.array.indexer.indexVar!!)
+                    val asmvarname = asmgen.asmVariableName(target.array.indexer.indexExpr as IdentifierReference)
                     asmgen.out(" lda  $asmvarname")
                 }
                 asmgen.out(" jsr  floats.set_array_float")
@@ -1209,11 +1219,12 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                     RegisterOrPair.XY -> asmgen.out("  ldy  #0 |  ldx  $sourceName")
                     RegisterOrPair.FAC1, RegisterOrPair.FAC2 -> throw AssemblyError("expected typecasted byte to float")
                     in Cx16VirtualRegisters -> {
-                        asmgen.out("""
+                        asmgen.out(
+                            """
                             lda  $sourceName
-                            sta  cx16.${target.register.toString().toLowerCase()}
+                            sta  cx16.${target.register.toString().lowercase()}
                             lda  #0
-                            sta  cx16.${target.register.toString().toLowerCase()}+1
+                            sta  cx16.${target.register.toString().lowercase()}+1
                             """)
                     }
                     else -> throw AssemblyError("weird register")
@@ -1242,11 +1253,20 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                     """)
             }
             TargetStorageKind.ARRAY -> {
-                // TODO optimize slow stack evaluation for this case, see assignVariableUByteIntoWord
-                if(this.asmgen.options.slowCodegenWarnings)
-                    println("warning: slow stack evaluation used for sign-extend byte typecast at ${bytevar.position}")
-                asmgen.translateExpression(wordtarget.origAssign.source.expression!!)
-                assignStackValue(wordtarget)
+                if (wordtarget.constArrayIndexValue!=null) {
+                    val scaledIdx = wordtarget.constArrayIndexValue!! * 2
+                    asmgen.out("  lda  $sourceName")
+                    asmgen.signExtendAYlsb(DataType.BYTE)
+                    asmgen.out("  sta  ${wordtarget.asmVarname}+$scaledIdx |  sty  ${wordtarget.asmVarname}+$scaledIdx+1")
+                }
+                else {
+                    asmgen.saveRegisterLocal(CpuRegister.X, wordtarget.scope!!)
+                    asmgen.loadScaledArrayIndexIntoRegister(wordtarget.array!!, wordtarget.datatype, CpuRegister.X)
+                    asmgen.out("  lda  $sourceName")
+                    asmgen.signExtendAYlsb(DataType.BYTE)
+                    asmgen.out("  sta  ${wordtarget.asmVarname},x |  inx |  tya |  sta  ${wordtarget.asmVarname},x")
+                    asmgen.restoreRegisterLocal(CpuRegister.X)
+                }
             }
             TargetStorageKind.REGISTER -> {
                 when(wordtarget.register!!) {
@@ -1339,12 +1359,20 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
     }
 
     internal fun assignRegisterByte(target: AsmAssignTarget, register: CpuRegister) {
-        if(target.register !in Cx16VirtualRegisters)
-            require(target.datatype in ByteDatatypes)
+        // we make an exception in the type check for assigning something to a cx16 virtual register
+        if(target.register !in Cx16VirtualRegisters) {
+            if(target.kind==TargetStorageKind.VARIABLE) {
+                val parts = target.asmVarname.split('.')
+                if (parts.size != 2 || parts[0] != "cx16")
+                    require(target.datatype in ByteDatatypes)
+            } else {
+                require(target.datatype in ByteDatatypes)
+            }
+        }
 
         when(target.kind) {
             TargetStorageKind.VARIABLE -> {
-                asmgen.out("  st${register.name.toLowerCase()}  ${target.asmVarname}")
+                asmgen.out("  st${register.name.lowercase()}  ${target.asmVarname}")
             }
             TargetStorageKind.MEMORY -> {
                 when(register) {
@@ -1368,7 +1396,8 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                         CpuRegister.X -> asmgen.out(" txa")
                         CpuRegister.Y -> asmgen.out(" tya")
                     }
-                    asmgen.out(" ldy  ${asmgen.asmVariableName(target.array!!.indexer.indexVar!!)} |  sta  ${target.asmVarname},y")
+                    val indexVar = target.array!!.indexer.indexExpr as IdentifierReference
+                    asmgen.out(" ldy  ${asmgen.asmVariableName(indexVar)} |  sta  ${target.asmVarname},y")
                 }
             }
             TargetStorageKind.REGISTER -> {
@@ -1383,7 +1412,7 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                         RegisterOrPair.FAC1, RegisterOrPair.FAC2 -> throw AssemblyError("expected type cast to float")
                         in Cx16VirtualRegisters -> {
                             // only assign a single byte to the virtual register's Lsb
-                            asmgen.out("  sta  cx16.${target.register.toString().toLowerCase()}")
+                            asmgen.out("  sta  cx16.${target.register.toString().lowercase()}")
                         }
                         else -> throw AssemblyError("weird register")
                     }
@@ -1397,7 +1426,7 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                         RegisterOrPair.FAC1, RegisterOrPair.FAC2 -> throw AssemblyError("expected type cast to float")
                         in Cx16VirtualRegisters -> {
                             // only assign a single byte to the virtual register's Lsb
-                            asmgen.out("  stx  cx16.${target.register.toString().toLowerCase()}")
+                            asmgen.out("  stx  cx16.${target.register.toString().lowercase()}")
                         }
                         else -> throw AssemblyError("weird register")
                     }
@@ -1411,7 +1440,7 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                         RegisterOrPair.FAC1, RegisterOrPair.FAC2 -> throw AssemblyError("expected type cast to float")
                         in Cx16VirtualRegisters -> {
                             // only assign a single byte to the virtual register's Lsb
-                            asmgen.out("  sty  cx16.${target.register.toString().toLowerCase()}")
+                            asmgen.out("  sty  cx16.${target.register.toString().lowercase()}")
                         }
                         else -> throw AssemblyError("weird register")
                     }
@@ -1501,9 +1530,10 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                         RegisterOrPair.AX -> { }
                         RegisterOrPair.XY -> { asmgen.out("  stx  P8ZP_SCRATCH_REG |  ldy  P8ZP_SCRATCH_REG |  tax") }
                         in Cx16VirtualRegisters -> {
-                            asmgen.out("""
-                                    sta  cx16.${target.register.toString().toLowerCase()}
-                                    stx  cx16.${target.register.toString().toLowerCase()}+1
+                            asmgen.out(
+                                """
+                                    sta  cx16.${target.register.toString().lowercase()}
+                                    stx  cx16.${target.register.toString().lowercase()}+1
                                 """)
                         }
                         else -> throw AssemblyError("expected reg pair or cx16 virtual 16-bit register")
@@ -1513,9 +1543,10 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                         RegisterOrPair.AX -> { asmgen.out("  sty  P8ZP_SCRATCH_REG |  ldx  P8ZP_SCRATCH_REG") }
                         RegisterOrPair.XY -> { asmgen.out("  tax") }
                         in Cx16VirtualRegisters -> {
-                            asmgen.out("""
-                                    sta  cx16.${target.register.toString().toLowerCase()}
-                                    sty  cx16.${target.register.toString().toLowerCase()}+1
+                            asmgen.out(
+                                """
+                                    sta  cx16.${target.register.toString().lowercase()}
+                                    sty  cx16.${target.register.toString().lowercase()}+1
                                 """)
                         }
                         else -> throw AssemblyError("expected reg pair or cx16 virtual 16-bit register")
@@ -1525,9 +1556,10 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                         RegisterOrPair.AX -> { asmgen.out("  txa |  sty  P8ZP_SCRATCH_REG |  ldx  P8ZP_SCRATCH_REG") }
                         RegisterOrPair.XY -> { }
                         in Cx16VirtualRegisters -> {
-                            asmgen.out("""
-                                    stx  cx16.${target.register.toString().toLowerCase()}
-                                    sty  cx16.${target.register.toString().toLowerCase()}+1
+                            asmgen.out(
+                                """
+                                    stx  cx16.${target.register.toString().lowercase()}
+                                    sty  cx16.${target.register.toString().lowercase()}+1
                                 """)
                         }
                         else -> throw AssemblyError("expected reg pair or cx16 virtual 16-bit register")
@@ -1594,7 +1626,10 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                         RegisterOrPair.AY -> asmgen.out("  lda  #0 |  tay")
                         RegisterOrPair.XY -> asmgen.out("  ldx  #0 |  ldy  #0")
                         in Cx16VirtualRegisters -> {
-                            asmgen.out("  stz  cx16.${target.register.toString().toLowerCase()} |  stz  cx16.${target.register.toString().toLowerCase()}+1")
+                            asmgen.out(
+                                "  stz  cx16.${
+                                    target.register.toString().lowercase()
+                                } |  stz  cx16.${target.register.toString().lowercase()}+1")
                         }
                         else -> throw AssemblyError("invalid register for word value")
                     }
@@ -1644,11 +1679,12 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                     RegisterOrPair.AY -> asmgen.out("  ldy  #>${word.toHex()} |  lda  #<${word.toHex()}")
                     RegisterOrPair.XY -> asmgen.out("  ldy  #>${word.toHex()} |  ldx  #<${word.toHex()}")
                     in Cx16VirtualRegisters -> {
-                        asmgen.out("""
+                        asmgen.out(
+                            """
                             lda  #<${word.toHex()}
-                            sta  cx16.${target.register.toString().toLowerCase()}
+                            sta  cx16.${target.register.toString().lowercase()}
                             lda  #>${word.toHex()}
-                            sta  cx16.${target.register.toString().toLowerCase()}+1
+                            sta  cx16.${target.register.toString().lowercase()}+1
                             """)
                     }
                     else -> throw AssemblyError("invalid register for word value")
@@ -1695,7 +1731,10 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                     RegisterOrPair.XY -> asmgen.out("  ldx  #0 |  ldy  #0")
                     RegisterOrPair.FAC1, RegisterOrPair.FAC2 -> throw AssemblyError("expected typecasted byte to float")
                     in Cx16VirtualRegisters -> {
-                        asmgen.out("  stz  cx16.${target.register.toString().toLowerCase()} |  stz  cx16.${target.register.toString().toLowerCase()}+1")
+                        asmgen.out(
+                            "  stz  cx16.${
+                                target.register.toString().lowercase()
+                            } |  stz  cx16.${target.register.toString().lowercase()}+1")
                     }
                     else -> throw AssemblyError("weird register")
                 }
@@ -1735,11 +1774,17 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                 RegisterOrPair.XY -> asmgen.out("  ldy  #0 |  ldx  #${byte.toHex()}")
                 RegisterOrPair.FAC1, RegisterOrPair.FAC2 -> throw AssemblyError("expected typecasted byte to float")
                 in Cx16VirtualRegisters -> {
-                    asmgen.out("  lda  #${byte.toHex()} |  sta  cx16.${target.register.toString().toLowerCase()}")
+                    asmgen.out(
+                        "  lda  #${byte.toHex()} |  sta  cx16.${
+                            target.register.toString().lowercase()
+                        }")
                     if(asmgen.isTargetCpu(CpuType.CPU65c02))
-                        asmgen.out("  stz  cx16.${target.register.toString().toLowerCase()}+1\n")
+                        asmgen.out("  stz  cx16.${target.register.toString().lowercase()}+1\n")
                     else
-                        asmgen.out("  lda  #0 |  sta  cx16.${target.register.toString().toLowerCase()}+1\n")
+                        asmgen.out(
+                            "  lda  #0 |  sta  cx16.${
+                                target.register.toString().lowercase()
+                            }+1\n")
                 }
                 else -> throw AssemblyError("weird register")
             }
@@ -1776,8 +1821,9 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                         """)
                 }
                 TargetStorageKind.ARRAY -> {
-                    if (target.array!!.indexer.indexNum!=null) {
-                        val indexValue = target.array.indexer.constIndex()!! * program.memsizer.memorySize(DataType.FLOAT)
+                    val constIndex = target.array!!.indexer.constIndex()
+                    if (constIndex!=null) {
+                        val indexValue = constIndex * program.memsizer.memorySize(DataType.FLOAT)
                         if(asmgen.isTargetCpu(CpuType.CPU65c02))
                             asmgen.out("""
                                 stz  ${target.asmVarname}+$indexValue
@@ -1796,7 +1842,7 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                                 sta  ${target.asmVarname}+$indexValue+4
                             """)
                     } else {
-                        val asmvarname = asmgen.asmVariableName(target.array.indexer.indexVar!!)
+                        val asmvarname = asmgen.asmVariableName(target.array.indexer.indexExpr as IdentifierReference)
                         asmgen.out("""
                             lda  #<${target.asmVarname}
                             sta  P8ZP_SCRATCH_W1
@@ -1841,8 +1887,9 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                 }
                 TargetStorageKind.ARRAY -> {
                     val arrayVarName = target.asmVarname
-                    if (target.array!!.indexer.indexNum!=null) {
-                        val indexValue = target.array.indexer.constIndex()!! * program.memsizer.memorySize(DataType.FLOAT)
+                    val constIndex = target.array!!.indexer.constIndex()
+                    if (constIndex!=null) {
+                        val indexValue = constIndex * program.memsizer.memorySize(DataType.FLOAT)
                         asmgen.out("""
                             lda  $constFloat
                             sta  $arrayVarName+$indexValue
@@ -1856,7 +1903,7 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                             sta  $arrayVarName+$indexValue+4
                         """)
                     } else {
-                        val asmvarname = asmgen.asmVariableName(target.array.indexer.indexVar!!)
+                        val asmvarname = asmgen.asmVariableName(target.array.indexer.indexExpr as IdentifierReference)
                         asmgen.out("""
                             lda  #<${constFloat}
                             sta  P8ZP_SCRATCH_W1
@@ -1913,11 +1960,12 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                     RegisterOrPair.XY -> asmgen.out("  ldy  #0 |  ldy  ${address.toHex()}")
                     RegisterOrPair.FAC1, RegisterOrPair.FAC2 -> throw AssemblyError("expected typecasted byte to float")
                     in Cx16VirtualRegisters -> {
-                        asmgen.out("""
+                        asmgen.out(
+                            """
                             lda  ${address.toHex()}
-                            sta  cx16.${target.register.toString().toLowerCase()}
+                            sta  cx16.${target.register.toString().lowercase()}
                             lda  #0
-                            sta  cx16.${target.register.toString().toLowerCase()}+1
+                            sta  cx16.${target.register.toString().lowercase()}+1
                         """)
                     }
                     else -> throw AssemblyError("weird register")
@@ -1953,10 +2001,11 @@ internal class AssignmentAsmGen(private val program: Program, private val asmgen
                         RegisterOrPair.XY -> asmgen.out("  tax |  ldy  #0")
                         RegisterOrPair.FAC1, RegisterOrPair.FAC2 -> throw AssemblyError("expected typecasted byte to float")
                         in Cx16VirtualRegisters -> {
-                            asmgen.out("""
-                                sta  cx16.${target.register.toString().toLowerCase()}
+                            asmgen.out(
+                                """
+                                sta  cx16.${target.register.toString().lowercase()}
                                 lda  #0
-                                sta  cx16.${target.register.toString().toLowerCase()}+1
+                                sta  cx16.${target.register.toString().lowercase()}+1
                             """)
                         }
                         else -> throw AssemblyError("weird register")

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

@@ -1,4 +1,4 @@
-package prog8.compiler.target.c64.codegen.assignment
+package prog8.compiler.target.cpu6502.codegen.assignment
 
 import prog8.ast.Program
 import prog8.ast.base.*
@@ -7,13 +7,14 @@ import prog8.ast.statements.Subroutine
 import prog8.ast.toHex
 import prog8.compiler.AssemblyError
 import prog8.compiler.target.CpuType
-import prog8.compiler.target.c64.codegen.AsmGen
-import prog8.compiler.target.c64.codegen.ExpressionsAsmGen
+import prog8.compiler.target.cpu6502.codegen.AsmGen
+import prog8.compiler.target.cpu6502.codegen.ExpressionsAsmGen
 
 internal class AugmentableAssignmentAsmGen(private val program: Program,
                                            private val assignmentAsmGen: AssignmentAsmGen,
                                            private val exprAsmGen: ExpressionsAsmGen,
-                                           private val asmgen: AsmGen) {
+                                           private val asmgen: AsmGen
+) {
     fun translate(assign: AsmAssignment) {
         require(assign.isAugmentable)
         require(assign.source.kind== SourceStorageKind.EXPRESSION)
@@ -24,7 +25,7 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                 val itype = value.inferType(program)
                 if(!itype.isKnown)
                     throw AssemblyError("unknown dt")
-                val type = itype.typeOrElse(DataType.STRUCT)
+                val type = itype.typeOrElse(DataType.UNDEFINED)
                 when (value.operator) {
                     "+" -> {}
                     "-" -> inplaceNegate(assign.target, type)
@@ -109,7 +110,7 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
         val ident = value as? IdentifierReference
         val memread = value as? DirectMemoryRead
 
-        when(target.kind) {
+        when (target.kind) {
             TargetStorageKind.VARIABLE -> {
                 when (target.datatype) {
                     in ByteDatatypes -> {
@@ -159,7 +160,7 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                         when {
                             valueLv != null -> inplaceModification_byte_litval_to_variable(addr.toHex(), DataType.UBYTE, operator, valueLv.toInt())
                             ident != null -> inplaceModification_byte_variable_to_variable(addr.toHex(), DataType.UBYTE, operator, ident)
-                            // TODO more specialized code for types such as memory read etc.  -> inplaceModification_byte_memread_to_variable()
+                            memread != null -> inplaceModification_byte_memread_to_variable(addr.toHex(), DataType.UBYTE, operator, value)
                             value is TypecastExpression -> {
                                 if (tryRemoveRedundantCast(value, target, operator)) return
                                 inplaceModification_byte_value_to_variable(addr.toHex(), DataType.UBYTE, operator, value)
@@ -198,10 +199,12 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
             }
             TargetStorageKind.ARRAY -> {
                 with(target.array!!.indexer) {
+                    val indexNum = indexExpr as? NumericLiteralValue
+                    val indexVar = indexExpr as? IdentifierReference
                     when {
                         indexNum!=null -> {
-                            val targetVarName = "${target.asmVarname} + ${indexNum!!.number.toInt()*program.memsizer.memorySize(target.datatype)}"
-                            when(target.datatype) {
+                            val targetVarName = "${target.asmVarname} + ${indexNum.number.toInt()*program.memsizer.memorySize(target.datatype)}"
+                            when (target.datatype) {
                                 in ByteDatatypes -> {
                                     when {
                                         valueLv != null -> inplaceModification_byte_litval_to_variable(targetVarName, target.datatype, operator, valueLv.toInt())
@@ -241,7 +244,7 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                             }
                         }
                         indexVar!=null -> {
-                            when(target.datatype) {
+                            when (target.datatype) {
                                 in ByteDatatypes -> {
                                     val tgt = AsmAssignTarget.fromRegisters(RegisterOrPair.A, null, program, asmgen)
                                     val assign = AsmAssignment(target.origAssign.source, tgt, false, program.memsizer, value.position)
@@ -267,8 +270,8 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                     }
                 }
             }
-            TargetStorageKind.REGISTER -> TODO("reg in-place modification")
-            TargetStorageKind.STACK -> TODO("stack in-place modification")
+            TargetStorageKind.REGISTER -> throw AssemblyError("missing codegen for reg in-place modification")
+            TargetStorageKind.STACK -> throw AssemblyError("missing codegen for stack in-place modification")
         }
     }
 
@@ -277,7 +280,7 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
             val childIDt = value.expression.inferType(program)
             if(!childIDt.isKnown)
                 throw AssemblyError("unknown dt")
-            val childDt = childIDt.typeOrElse(DataType.STRUCT)
+            val childDt = childIDt.typeOrElse(DataType.UNDEFINED)
             if (value.type!=DataType.FLOAT && (value.type.equalsSize(childDt) || value.type.largerThan(childDt))) {
                 // this typecast is redundant here; the rest of the code knows how to deal with the uncasted value.
                 // (works for integer types, not for float.)
@@ -319,7 +322,6 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
             "&", "and" -> asmgen.out(" and  P8ZP_SCRATCH_B1")
             "|", "or" -> asmgen.out(" ora  P8ZP_SCRATCH_B1")
             "^", "xor" -> asmgen.out(" eor  P8ZP_SCRATCH_B1")
-            in comparisonOperators -> TODO("in-place modification for $operator")
             else -> throw AssemblyError("invalid operator for in-place modification $operator")
         }
         if(ptrOnZp)
@@ -360,7 +362,6 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
             "&", "and" -> asmgen.out(" and  $otherName")
             "|", "or" -> asmgen.out(" ora  $otherName")
             "^", "xor" -> asmgen.out(" eor  $otherName")
-            in comparisonOperators -> TODO("in-place modification for $operator")
             else -> throw AssemblyError("invalid operator for in-place modification $operator")
         }
         if(ptrOnZp)
@@ -463,7 +464,6 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                 else
                     asmgen.out("  sta  (P8ZP_SCRATCH_W1),y")
             }
-            in comparisonOperators -> TODO("in-place modification for $operator")
             else -> throw AssemblyError("invalid operator for in-place modification $operator")
         }
     }
@@ -539,7 +539,6 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                 asmgen.assignExpressionToRegister(value, RegisterOrPair.A)
                 asmgen.out("  eor  $name |  sta  $name")
             }
-            in comparisonOperators -> TODO("in-place modification for $operator")
             else -> throw AssemblyError("invalid operator for in-place modification $operator")
         }
     }
@@ -597,7 +596,6 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
             "&", "and" -> asmgen.out(" lda  $name |  and  $otherName |  sta  $name")
             "|", "or" -> asmgen.out(" lda  $name |  ora  $otherName |  sta  $name")
             "^", "xor" -> asmgen.out(" lda  $name |  eor  $otherName |  sta  $name")
-            in comparisonOperators -> TODO("in-place modification for $operator")
             else -> throw AssemblyError("invalid operator for in-place modification $operator")
         }
     }
@@ -669,13 +667,12 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
             "&", "and" -> asmgen.out(" lda  $name |  and  #$value |  sta  $name")
             "|", "or" -> asmgen.out(" lda  $name |  ora  #$value |  sta  $name")
             "^", "xor" -> asmgen.out(" lda  $name |  eor  #$value |  sta  $name")
-            in comparisonOperators -> TODO("in-place modification for $operator")
             else -> throw AssemblyError("invalid operator for in-place modification $operator")
         }
     }
 
     private fun inplaceModification_byte_memread_to_variable(name: String, dt: DataType, operator: String, memread: DirectMemoryRead) {
-        when(operator) {
+        when (operator) {
             "+" -> {
                 exprAsmGen.translateDirectMemReadExpression(memread, false)
                 asmgen.out("""
@@ -691,8 +688,20 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                     sec
                     sbc  P8ZP_SCRATCH_B1
                     sta  $name""")
-                // TODO: tuned code for more operators
             }
+            "|", "or" -> {
+                exprAsmGen.translateDirectMemReadExpression(memread, false)
+                asmgen.out("  ora  $name  |  sta  $name")
+            }
+            "&", "and" -> {
+                exprAsmGen.translateDirectMemReadExpression(memread, false)
+                asmgen.out("  and  $name  |  sta  $name")
+            }
+            "^", "xor" -> {
+                exprAsmGen.translateDirectMemReadExpression(memread, false)
+                asmgen.out("  eor  $name  |  sta  $name")
+            }
+            // TODO: tuned code for more operators
             else -> {
                 inplaceModification_byte_value_to_variable(name, dt, operator, memread)
             }
@@ -700,7 +709,7 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
     }
 
     private fun inplaceModification_word_memread_to_variable(name: String, dt: DataType, operator: String, memread: DirectMemoryRead) {
-        when(operator) {
+        when (operator) {
             "+" -> {
                 exprAsmGen.translateDirectMemReadExpression(memread, false)
                 asmgen.out("""
@@ -722,8 +731,26 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                     bcc  +
                     dec  $name+1
 +""")
-                // TODO: tuned code for more operators
             }
+            "|", "or" -> {
+                exprAsmGen.translateDirectMemReadExpression(memread, false)
+                asmgen.out("  ora  $name  |  sta  $name")
+            }
+            "&", "and" -> {
+                exprAsmGen.translateDirectMemReadExpression(memread, false)
+                asmgen.out("  and  $name  |  sta  $name")
+                if(dt in WordDatatypes) {
+                    if(asmgen.isTargetCpu(CpuType.CPU65c02))
+                        asmgen.out("  stz  $name+1")
+                    else
+                        asmgen.out("  lda  #0 |  sta  $name+1")
+                }
+            }
+            "^", "xor" -> {
+                exprAsmGen.translateDirectMemReadExpression(memread, false)
+                asmgen.out("  eor  $name  |  sta  $name")
+            }
+            // TODO: tuned code for more operators
             else -> {
                 inplaceModification_word_value_to_variable(name, dt, operator, memread)
             }
@@ -977,7 +1004,6 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                     else -> asmgen.out("  lda  $name |  eor  #<$value |  sta  $name |  lda  $name+1 |  eor  #>$value |  sta  $name+1")
                 }
             }
-            in comparisonOperators -> TODO("in-place modification for $operator")
             else -> throw AssemblyError("invalid operator for in-place modification $operator")
         }
     }
@@ -1053,8 +1079,49 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                             lda  math.multiply_words.result+1
                             sta  $name+1""")
                     }
-                    "/" -> TODO("div (u)wordvar/bytevar")
-                    "%" -> TODO("(u)word remainder bytevar")
+                    "/" -> {
+                        if(dt==DataType.UWORD) {
+                            asmgen.out("""
+                                lda  $name
+                                ldy  $name+1
+                                sta  P8ZP_SCRATCH_W1
+                                sty  P8ZP_SCRATCH_W1+1
+                                lda  $otherName
+                                ldy  #0
+                                jsr  math.divmod_uw_asm
+                                sta  $name
+                                sty  $name+1
+                            """)
+                        } else {
+                            asmgen.out("""
+                                lda  $name
+                                ldy  $name+1
+                                sta  P8ZP_SCRATCH_W1
+                                sty  P8ZP_SCRATCH_W1+1
+                                lda  $otherName
+                                ldy  #0
+                                jsr  math.divmod_w_asm
+                                sta  $name
+                                sty  $name+1
+                            """)
+                        }
+                    }
+                    "%" -> {
+                        if(valueDt!=DataType.UBYTE || dt!=DataType.UWORD)
+                            throw AssemblyError("remainder of signed integers is not properly defined/implemented, use unsigned instead")
+                        asmgen.out("""
+                            lda  $name
+                            ldy  $name+1
+                            sta  P8ZP_SCRATCH_W1
+                            sty  P8ZP_SCRATCH_W1+1
+                            lda  $otherName
+                            ldy  #0
+                            jsr  math.divmod_uw_asm
+                            lda  P8ZP_SCRATCH_W2
+                            sta  $name
+                            lda  P8ZP_SCRATCH_W2+1
+                            sta  $name+1
+                        """)                    }
                     "<<" -> {
                         asmgen.out("""
                         ldy  $otherName
@@ -1099,7 +1166,6 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                     }
                     "|", "or" -> asmgen.out("  lda  $otherName |  ora  $name |  sta  $name")
                     "^", "xor" -> asmgen.out("  lda  $otherName |  eor  $name |  sta  $name")
-                    in comparisonOperators -> TODO("in-place modification for $operator")
                     else -> throw AssemblyError("invalid operator for in-place modification $operator")
                 }
             }
@@ -1173,7 +1239,6 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                     "&", "and" -> asmgen.out(" lda  $name |  and  $otherName |  sta  $name |  lda  $name+1 |  and  $otherName+1 |  sta  $name+1")
                     "|", "or" -> asmgen.out(" lda  $name |  ora  $otherName |  sta  $name |  lda  $name+1 |  ora  $otherName+1 |  sta  $name+1")
                     "^", "xor" -> asmgen.out(" lda  $name |  eor  $otherName |  sta  $name |  lda  $name+1 |  eor  $otherName+1 |  sta  $name+1")
-                    in comparisonOperators -> TODO("in-place modification for $operator")
                     else -> throw AssemblyError("invalid operator for in-place modification $operator")
                 }
             }
@@ -1190,7 +1255,7 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
         val valueiDt = value.inferType(program)
         if(!valueiDt.isKnown)
             throw AssemblyError("unknown dt")
-        val valueDt = valueiDt.typeOrElse(DataType.STRUCT)
+        val valueDt = valueiDt.typeOrElse(DataType.UNDEFINED)
 
         fun multiplyVarByWordInAY() {
             asmgen.out("""
@@ -1239,7 +1304,7 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
             """)
         }
 
-        when(valueDt) {
+        when (valueDt) {
             in ByteDatatypes -> {
                 // the other variable is a BYTE type so optimize for that
                 when (operator) {
@@ -1296,21 +1361,21 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                     }
                     "*" -> {
                         // stack contains (u) byte value, sign extend that and proceed with regular 16 bit operation
-                        // TODO use an optimized word * byte multiplication routine
+                        // TODO use an optimized word * byte multiplication routine?
                         asmgen.assignExpressionToRegister(value, RegisterOrPair.A)
                         asmgen.signExtendAYlsb(valueDt)
                         multiplyVarByWordInAY()
                     }
                     "/" -> {
                         // stack contains (u) byte value, sign extend that and proceed with regular 16 bit operation
-                        // TODO use an optimized word / byte divmod routine
+                        // TODO use an optimized word / byte divmod routine?
                         asmgen.assignExpressionToRegister(value, RegisterOrPair.A)
                         asmgen.signExtendAYlsb(valueDt)
                         divideVarByWordInAY()
                     }
                     "%" -> {
                         // stack contains (u) byte value, sign extend that and proceed with regular 16 bit operation
-                        // TODO use an optimized word / byte divmod routine
+                        // TODO use an optimized word / byte divmod routine?
                         asmgen.assignExpressionToRegister(value, RegisterOrPair.A)
                         asmgen.signExtendAYlsb(valueDt)
                         remainderVarByWordInAY()
@@ -1364,7 +1429,6 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                         asmgen.assignExpressionToRegister(value, RegisterOrPair.A)
                         asmgen.out("  eor  $name |  sta  $name")
                     }
-                    in comparisonOperators -> TODO("in-place modification for $operator")
                     else -> throw AssemblyError("invalid operator for in-place modification $operator")
                 }
             }
@@ -1405,7 +1469,6 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                         asmgen.assignExpressionToRegister(value, RegisterOrPair.AY)
                         asmgen.out("  eor  $name |  sta  $name |  tya |  eor  $name+1 |  sta  $name+1")
                     }
-                    in comparisonOperators -> TODO("in-place modification for $operator")
                     else -> throw AssemblyError("invalid operator for in-place modification $operator")
                 }
             }
@@ -1453,7 +1516,6 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                     jsr  floats.FDIV
                 """)
             }
-            in comparisonOperators -> TODO("in-place float modification for $operator")
             else -> throw AssemblyError("invalid operator for in-place float modification $operator")
         }
         asmgen.out("""
@@ -1534,7 +1596,6 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                     jsr  floats.FDIV
                 """)
             }
-            in comparisonOperators -> TODO("in-place float modification for $operator")
             else -> throw AssemblyError("invalid operator for in-place float modification $operator")
         }
         // store Fac1 back into memory
@@ -1619,7 +1680,6 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                     jsr  floats.FDIV
                 """)
             }
-            in comparisonOperators -> TODO("in-place float modification for $operator")
             else -> throw AssemblyError("invalid operator for in-place float modification $operator")
         }
         // store Fac1 back into memory
@@ -1641,7 +1701,7 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                 DataType.UWORD, DataType.WORD -> {
                     when (outerCastDt) {
                         DataType.UBYTE, DataType.BYTE -> {
-                            when(target.kind) {
+                            when (target.kind) {
                                 TargetStorageKind.VARIABLE -> {
                                     if(asmgen.isTargetCpu(CpuType.CPU65c02))
                                         asmgen.out(" stz  ${target.asmVarname}+1")
@@ -1685,7 +1745,7 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
     private fun inplaceBooleanNot(target: AsmAssignTarget, dt: DataType) {
         when (dt) {
             DataType.UBYTE -> {
-                when(target.kind) {
+                when (target.kind) {
                     TargetStorageKind.VARIABLE -> {
                         asmgen.out("""
                             lda  ${target.asmVarname}
@@ -1729,13 +1789,13 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                             }
                         }
                     }
-                    TargetStorageKind.ARRAY -> TODO("in-place not of ubyte array")
-                    TargetStorageKind.REGISTER -> TODO("reg not")
-                    TargetStorageKind.STACK -> TODO("stack not")
+                    TargetStorageKind.ARRAY -> throw AssemblyError("missing codegen for in-place not of ubyte array")
+                    TargetStorageKind.REGISTER -> throw AssemblyError("missing codegen for reg not")
+                    TargetStorageKind.STACK -> throw AssemblyError("missing codegen for stack not")
                 }
             }
             DataType.UWORD -> {
-                when(target.kind) {
+                when (target.kind) {
                     TargetStorageKind.VARIABLE -> {
                         asmgen.out("""
                             lda  ${target.asmVarname}
@@ -1748,9 +1808,9 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                             sta  ${target.asmVarname}+1""")
                     }
                     TargetStorageKind.MEMORY -> throw AssemblyError("no asm gen for uword-memory not")
-                    TargetStorageKind.ARRAY -> TODO("in-place not of uword array")
-                    TargetStorageKind.REGISTER -> TODO("reg not")
-                    TargetStorageKind.STACK -> TODO("stack not")
+                    TargetStorageKind.ARRAY -> throw AssemblyError("missing codegen for in-place not of uword array")
+                    TargetStorageKind.REGISTER -> throw AssemblyError("missing codegen for reg not")
+                    TargetStorageKind.STACK -> throw AssemblyError("missing codegen for stack not")
                 }
             }
             else -> throw AssemblyError("boolean-not of invalid type")
@@ -1760,7 +1820,7 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
     private fun inplaceInvert(target: AsmAssignTarget, dt: DataType) {
         when (dt) {
             DataType.UBYTE -> {
-                when(target.kind) {
+                when (target.kind) {
                     TargetStorageKind.VARIABLE -> {
                         asmgen.out("""
                             lda  ${target.asmVarname}
@@ -1795,13 +1855,13 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                             }
                         }
                     }
-                    TargetStorageKind.ARRAY -> TODO("in-place invert ubyte array")
-                    TargetStorageKind.REGISTER -> TODO("reg invert")
-                    TargetStorageKind.STACK -> TODO("stack invert")
+                    TargetStorageKind.ARRAY -> throw AssemblyError("missing codegen for in-place invert ubyte array")
+                    TargetStorageKind.REGISTER -> throw AssemblyError("missing codegen for reg invert")
+                    TargetStorageKind.STACK -> throw AssemblyError("missing codegen for stack invert")
                 }
             }
             DataType.UWORD -> {
-                when(target.kind) {
+                when (target.kind) {
                     TargetStorageKind.VARIABLE -> {
                         asmgen.out("""
                             lda  ${target.asmVarname}
@@ -1812,9 +1872,9 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                             sta  ${target.asmVarname}+1""")
                     }
                     TargetStorageKind.MEMORY -> throw AssemblyError("no asm gen for uword-memory invert")
-                    TargetStorageKind.ARRAY -> TODO("in-place invert uword array")
-                    TargetStorageKind.REGISTER -> TODO("reg invert")
-                    TargetStorageKind.STACK -> TODO("stack invert")
+                    TargetStorageKind.ARRAY -> throw AssemblyError("missing codegen for in-place invert uword array")
+                    TargetStorageKind.REGISTER -> throw AssemblyError("missing codegen for reg invert")
+                    TargetStorageKind.STACK -> throw AssemblyError("missing codegen for stack invert")
                 }
             }
             else -> throw AssemblyError("invert of invalid type")
@@ -1833,13 +1893,13 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                             sta  ${target.asmVarname}""")
                     }
                     TargetStorageKind.MEMORY -> throw AssemblyError("can't in-place negate memory ubyte")
-                    TargetStorageKind.ARRAY -> TODO("in-place negate byte array")
-                    TargetStorageKind.REGISTER -> TODO("reg negate")
-                    TargetStorageKind.STACK -> TODO("stack negate")
+                    TargetStorageKind.ARRAY -> throw AssemblyError("missing codegen for in-place negate byte array")
+                    TargetStorageKind.REGISTER -> throw AssemblyError("missing codegen for reg negate")
+                    TargetStorageKind.STACK -> throw AssemblyError("missing codegen for stack negate")
                 }
             }
             DataType.WORD -> {
-                when(target.kind) {
+                when (target.kind) {
                     TargetStorageKind.VARIABLE -> {
                         asmgen.out("""
                             lda  #0
@@ -1850,14 +1910,14 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                             sbc  ${target.asmVarname}+1
                             sta  ${target.asmVarname}+1""")
                     }
-                    TargetStorageKind.ARRAY -> TODO("in-place negate word array")
+                    TargetStorageKind.ARRAY -> throw AssemblyError("missing codegen for in-place negate word array")
                     TargetStorageKind.MEMORY -> throw AssemblyError("no asm gen for word memory negate")
-                    TargetStorageKind.REGISTER -> TODO("reg negate")
-                    TargetStorageKind.STACK -> TODO("stack negate")
+                    TargetStorageKind.REGISTER -> throw AssemblyError("missing codegen for reg negate")
+                    TargetStorageKind.STACK -> throw AssemblyError("missing codegen for stack negate")
                 }
             }
             DataType.FLOAT -> {
-                when(target.kind) {
+                when (target.kind) {
                     TargetStorageKind.VARIABLE -> {
                         // simply flip the sign bit in the float
                         asmgen.out("""
@@ -1866,8 +1926,8 @@ internal class AugmentableAssignmentAsmGen(private val program: Program,
                             sta  ${target.asmVarname}+1
                         """)
                     }
-                    TargetStorageKind.ARRAY -> TODO("in-place negate float array")
-                    TargetStorageKind.STACK -> TODO("stack float negate")
+                    TargetStorageKind.ARRAY -> throw AssemblyError("missing codegen for in-place negate float array")
+                    TargetStorageKind.STACK -> throw AssemblyError("missing codegen for stack float negate")
                     else -> throw AssemblyError("weird target kind for float")
                 }
             }

compiler/src/prog8/optimizer/BinExprSplitter.kt

@@ -1,8 +1,10 @@
 package prog8.optimizer
 
+import prog8.ast.INameScope
 import prog8.ast.Node
 import prog8.ast.Program
-import prog8.ast.expressions.*
+import prog8.ast.expressions.BinaryExpression
+import prog8.ast.expressions.augmentAssignmentOperators
 import prog8.ast.statements.AssignTarget
 import prog8.ast.statements.Assignment
 import prog8.ast.walk.AstWalker
@@ -11,7 +13,6 @@ import prog8.compiler.target.ICompilationTarget
 
 
 internal class BinExprSplitter(private val program: Program, private val compTarget: ICompilationTarget) : AstWalker() {
-    private val noModifications = emptyList<IAstModification>()
 
 //    override fun after(decl: VarDecl, parent: Node): Iterable<IAstModification> {
 // TODO somehow if we do this, the resulting code for some programs (cube3d.p8) gets hundreds of bytes larger...:
@@ -57,13 +58,14 @@ X =      BinExpr                                    X   =   LeftExpr
                 if(assignment.target isSameAs binExpr.left || assignment.target isSameAs binExpr.right)
                     return noModifications
 
-                if(isSimpleExpression(binExpr.right) && !assignment.isAugmentable) {
-                    val firstAssign = Assignment(assignment.target, binExpr.left, binExpr.left.position)
+                if(binExpr.right.isSimple && !assignment.isAugmentable) {
+                    val firstAssign = Assignment(assignment.target.copy(), binExpr.left, binExpr.left.position)
                     val targetExpr = assignment.target.toExpression()
                     val augExpr = BinaryExpression(targetExpr, binExpr.operator, binExpr.right, binExpr.right.position)
                     return listOf(
-                            IAstModification.InsertBefore(assignment, firstAssign, assignment.definingScope()),
-                            IAstModification.ReplaceNode(assignment.value, augExpr, assignment))
+                        IAstModification.ReplaceNode(binExpr, augExpr, assignment),
+                        IAstModification.InsertBefore(assignment, firstAssign, assignment.parent as INameScope)
+                    )
                 }
             }
 
@@ -75,9 +77,6 @@ X =      BinExpr                                    X   =   LeftExpr
         return noModifications
     }
 
-    private fun isSimpleExpression(expr: Expression) =
-            expr is IdentifierReference || expr is NumericLiteralValue || expr is AddressOf || expr is DirectMemoryRead || expr is StringLiteralValue || expr is ArrayLiteralValue || expr is RangeExpr
-
     private fun isSimpleTarget(target: AssignTarget, program: Program) =
             if (target.identifier!=null || target.memoryAddress!=null)
                 compTarget.isInRegularRAM(target, program)

compiler/src/prog8/optimizer/CallGraph.kt

@@ -1,139 +1,71 @@
 package prog8.optimizer
 
-import prog8.ast.INameScope
 import prog8.ast.Module
 import prog8.ast.Node
 import prog8.ast.Program
-import prog8.ast.base.DataType
-import prog8.ast.base.ParentSentinel
 import prog8.ast.base.Position
+import prog8.ast.base.VarDeclType
 import prog8.ast.expressions.AddressOf
 import prog8.ast.expressions.FunctionCall
 import prog8.ast.expressions.IdentifierReference
 import prog8.ast.statements.*
 import prog8.ast.walk.IAstVisitor
 import prog8.compiler.IErrorReporter
-import java.nio.file.Path
-
-private val alwaysKeepSubroutines = setOf(
-        Pair("main", "start")
-)
-
-private val asmJumpRx = Regex("""[\-+a-zA-Z0-9_ \t]+(jmp|jsr)[ \t]+(\S+).*""", RegexOption.IGNORE_CASE)
-private val asmRefRx = Regex("""[\-+a-zA-Z0-9_ \t]+(...)[ \t]+(\S+).*""", RegexOption.IGNORE_CASE)
 
 
-class CallGraph(private val program: Program, private val asmFileLoader: (filename: String, source: Path)->String) : IAstVisitor {
+class CallGraph(private val program: Program) : IAstVisitor {
 
-    val imports = mutableMapOf<Module, List<Module>>().withDefault { mutableListOf() }
-    val importedBy = mutableMapOf<Module, List<Module>>().withDefault { mutableListOf() }
-    val calls = mutableMapOf<Subroutine, List<Subroutine>>().withDefault { mutableListOf() }
-    val calledBy = mutableMapOf<Subroutine, List<Node>>().withDefault { mutableListOf() }
-
-    // TODO  add dataflow graph: what statements use what variables - can be used to eliminate unused vars
-    val usedSymbols = mutableSetOf<Statement>()
+    val imports = mutableMapOf<Module, Set<Module>>().withDefault { setOf() }
+    val importedBy = mutableMapOf<Module, Set<Module>>().withDefault { setOf() }
+    val calls = mutableMapOf<Subroutine, Set<Subroutine>>().withDefault { setOf() }
+    val calledBy = mutableMapOf<Subroutine, Set<Node>>().withDefault { setOf() }
+    private val allIdentifiersAndTargets = mutableMapOf<Pair<IdentifierReference, Position>, Statement>()
+    private val allAssemblyNodes = mutableListOf<InlineAssembly>()
 
     init {
         visit(program)
     }
 
-    fun forAllSubroutines(scope: INameScope, sub: (s: Subroutine) -> Unit) {
-        fun findSubs(scope: INameScope) {
-            scope.statements.forEach {
-                if (it is Subroutine)
-                    sub(it)
-                if (it is INameScope)
-                    findSubs(it)
+    private val usedSubroutines: Set<Subroutine> by lazy {
+        calledBy.keys + program.entrypoint()
+    }
+
+    private val usedBlocks: Set<Block> by lazy {
+        val blocksFromSubroutines = usedSubroutines.map { it.definingBlock() }
+        val blocksFromLibraries = program.allBlocks().filter { it.isInLibrary }
+        val used = mutableSetOf<Block>()
+
+        allIdentifiersAndTargets.forEach {
+            if(it.key.first.definingBlock() in blocksFromSubroutines) {
+                val target = it.value.definingBlock()
+                used.add(target)
             }
         }
-        findSubs(scope)
+
+        used + blocksFromLibraries + program.entrypoint().definingBlock()
     }
 
-    override fun visit(program: Program) {
-        super.visit(program)
-
-        program.modules.forEach {
-            it.importedBy.clear()
-            it.imports.clear()
-
-            it.importedBy.addAll(importedBy.getValue(it))
-            it.imports.addAll(imports.getValue(it))
-        }
-
-        val rootmodule = program.modules.first()
-        rootmodule.importedBy.add(rootmodule)       // don't discard root module
-    }
-
-    override fun visit(block: Block) {
-        if (block.definingModule().isLibraryModule) {
-            // make sure the block is not removed
-            addNodeAndParentScopes(block)
-        }
-
-        super.visit(block)
+    private val usedModules: Set<Module> by lazy {
+        usedBlocks.map { it.definingModule() }.toSet()
     }
 
     override fun visit(directive: Directive) {
         val thisModule = directive.definingModule()
         if (directive.directive == "%import") {
             val importedModule: Module = program.modules.single { it.name == directive.args[0].name }
-            imports[thisModule] = imports.getValue(thisModule).plus(importedModule)
-            importedBy[importedModule] = importedBy.getValue(importedModule).plus(thisModule)
-        } else if (directive.directive == "%asminclude") {
-            val asm = asmFileLoader(directive.args[0].str!!, thisModule.source)
-            val scope = directive.definingSubroutine()
-            if(scope!=null) {
-                scanAssemblyCode(asm, directive, scope)
-            }
+            imports[thisModule] = imports.getValue(thisModule) + importedModule
+            importedBy[importedModule] = importedBy.getValue(importedModule) + thisModule
         }
 
         super.visit(directive)
     }
 
-    override fun visit(identifier: IdentifierReference) {
-        // track symbol usage
-        val target = identifier.targetStatement(program)
-        if (target != null) {
-            addNodeAndParentScopes(target)
-        }
-        super.visit(identifier)
-    }
-
-    private fun addNodeAndParentScopes(stmt: Statement) {
-        usedSymbols.add(stmt)
-        var node: Node = stmt
-        do {
-            if (node is INameScope && node is Statement) {
-                usedSymbols.add(node)
-            }
-            node = node.parent
-        } while (node !is Module && node !is ParentSentinel)
-    }
-
-    override fun visit(subroutine: Subroutine) {
-        if (Pair(subroutine.definingScope().name, subroutine.name) in alwaysKeepSubroutines
-                || subroutine.definingModule().isLibraryModule) {
-            // make sure the entrypoint is mentioned in the used symbols
-            addNodeAndParentScopes(subroutine)
-        }
-        super.visit(subroutine)
-    }
-
-    override fun visit(decl: VarDecl) {
-        if (decl.autogeneratedDontRemove || decl.datatype==DataType.STRUCT)
-            addNodeAndParentScopes(decl)
-        else if(decl.parent is Block && decl.definingModule().isLibraryModule)
-            addNodeAndParentScopes(decl)
-
-        super.visit(decl)
-    }
-
     override fun visit(functionCall: FunctionCall) {
         val otherSub = functionCall.target.targetSubroutine(program)
         if (otherSub != null) {
             functionCall.definingSubroutine()?.let { thisSub ->
-                calls[thisSub] = calls.getValue(thisSub).plus(otherSub)
-                calledBy[otherSub] = calledBy.getValue(otherSub).plus(functionCall)
+                calls[thisSub] = calls.getValue(thisSub) + otherSub
+                calledBy[otherSub] = calledBy.getValue(otherSub) + functionCall
             }
         }
         super.visit(functionCall)
@@ -143,8 +75,8 @@ class CallGraph(private val program: Program, private val asmFileLoader: (filena
         val otherSub = functionCallStatement.target.targetSubroutine(program)
         if (otherSub != null) {
             functionCallStatement.definingSubroutine()?.let { thisSub ->
-                calls[thisSub] = calls.getValue(thisSub).plus(otherSub)
-                calledBy[otherSub] = calledBy.getValue(otherSub).plus(functionCallStatement)
+                calls[thisSub] = calls.getValue(thisSub) + otherSub
+                calledBy[otherSub] = calledBy.getValue(otherSub) + functionCallStatement
             }
         }
         super.visit(functionCallStatement)
@@ -154,8 +86,8 @@ class CallGraph(private val program: Program, private val asmFileLoader: (filena
         val otherSub = addressOf.identifier.targetSubroutine(program)
         if(otherSub!=null) {
             addressOf.definingSubroutine()?.let { thisSub ->
-                calls[thisSub] = calls.getValue(thisSub).plus(otherSub)
-                calledBy[otherSub] = calledBy.getValue(otherSub).plus(thisSub)
+                calls[thisSub] = calls.getValue(thisSub) + otherSub
+                calledBy[otherSub] = calledBy.getValue(otherSub) + thisSub
             }
         }
         super.visit(addressOf)
@@ -165,63 +97,19 @@ class CallGraph(private val program: Program, private val asmFileLoader: (filena
         val otherSub = jump.identifier?.targetSubroutine(program)
         if (otherSub != null) {
             jump.definingSubroutine()?.let { thisSub ->
-                calls[thisSub] = calls.getValue(thisSub).plus(otherSub)
-                calledBy[otherSub] = calledBy.getValue(otherSub).plus(jump)
+                calls[thisSub] = calls.getValue(thisSub) + otherSub
+                calledBy[otherSub] = calledBy.getValue(otherSub) + jump
             }
         }
         super.visit(jump)
     }
 
-    override fun visit(structDecl: StructDecl) {
-        usedSymbols.add(structDecl)
-        usedSymbols.addAll(structDecl.statements)
+    override fun visit(identifier: IdentifierReference) {
+        allIdentifiersAndTargets[Pair(identifier, identifier.position)] = identifier.targetStatement(program)!!
     }
 
     override fun visit(inlineAssembly: InlineAssembly) {
-        // parse inline asm for subroutine calls (jmp, jsr)
-        val scope = inlineAssembly.definingSubroutine()
-        scanAssemblyCode(inlineAssembly.assembly, inlineAssembly, scope)
-        super.visit(inlineAssembly)
-    }
-
-    private fun scanAssemblyCode(asm: String, context: Statement, scope: Subroutine?) {
-        asm.lines().forEach { line ->
-            val matches = asmJumpRx.matchEntire(line)
-            if (matches != null) {
-                val jumptarget = matches.groups[2]?.value
-                if (jumptarget != null && (jumptarget[0].isLetter() || jumptarget[0] == '_')) {
-                    val node = program.namespace.lookup(jumptarget.split('.'), context)
-                    if (node is Subroutine) {
-                        if(scope!=null)
-                            calls[scope] = calls.getValue(scope).plus(node)
-                        calledBy[node] = calledBy.getValue(node).plus(context)
-                    } else if (jumptarget.contains('.')) {
-                        // maybe only the first part already refers to a subroutine
-                        val node2 = program.namespace.lookup(listOf(jumptarget.substringBefore('.')), context)
-                        if (node2 is Subroutine) {
-                            if(scope!=null)
-                                calls[scope] = calls.getValue(scope).plus(node2)
-                            calledBy[node2] = calledBy.getValue(node2).plus(context)
-                        }
-                    }
-                }
-            } else {
-                val matches2 = asmRefRx.matchEntire(line)
-                if (matches2 != null) {
-                    val target = matches2.groups[2]?.value
-                    if (target != null && (target[0].isLetter() || target[0] == '_')) {
-                        if (target.contains('.')) {
-                            val node = program.namespace.lookup(listOf(target.substringBefore('.')), context)
-                            if (node is Subroutine) {
-                                if(scope!=null)
-                                    calls[scope] = calls.getValue(scope).plus(node)
-                                calledBy[node] = calledBy.getValue(node).plus(context)
-                            }
-                        }
-                    }
-                }
-            }
-        }
+        allAssemblyNodes.add(inlineAssembly)
     }
 
     fun checkRecursiveCalls(errors: IErrorReporter) {
@@ -274,4 +162,39 @@ class CallGraph(private val program: Program, private val asmFileLoader: (filena
         recStack[sub] = false
         return false
     }
+
+    fun unused(module: Module) = module !in usedModules
+
+    fun unused(sub: Subroutine): Boolean {
+        return sub !in usedSubroutines && !nameInAssemblyCode(sub.name)
+    }
+
+    fun unused(block: Block): Boolean {
+        return block !in usedBlocks && !nameInAssemblyCode(block.name)
+    }
+
+    fun unused(decl: VarDecl): Boolean {
+        if(decl.type!=VarDeclType.VAR || decl.autogeneratedDontRemove || decl.sharedWithAsm)
+            return false
+
+        if(decl.definingBlock() !in usedBlocks)
+            return false
+
+        val allReferencedVardecls = allIdentifiersAndTargets.filter { it.value is VarDecl }.map { it.value }.toSet()
+        return decl !in allReferencedVardecls // Don't check assembly just for occurrences of variables, if they're not used in prog8 itself, just kill them
+    }
+
+    private fun nameInAssemblyCode(name: String) = allAssemblyNodes.any { it.assembly.contains(name) }
+
+    inline fun unused(label: Label) = false   // just always output labels
+
+    fun unused(stmt: ISymbolStatement): Boolean {
+        return when(stmt) {
+            is Subroutine -> unused(stmt)
+            is Block -> unused(stmt)
+            is VarDecl -> unused(stmt)
+            is Label -> false   // just always output labels
+            else -> false
+        }
+    }
 }

compiler/src/prog8/optimizer/ConstExprEvaluator.kt

@@ -9,28 +9,32 @@ import kotlin.math.pow
 class ConstExprEvaluator {
 
     fun evaluate(left: NumericLiteralValue, operator: String, right: NumericLiteralValue): Expression {
-        return when(operator) {
-            "+" -> plus(left, right)
-            "-" -> minus(left, right)
-            "*" -> multiply(left, right)
-            "/" -> divide(left, right)
-            "%" -> remainder(left, right)
-            "**" -> power(left, right)
-            "&" -> bitwiseand(left, right)
-            "|" -> bitwiseor(left, right)
-            "^" -> bitwisexor(left, right)
-            "and" -> logicaland(left, right)
-            "or" -> logicalor(left, right)
-            "xor" -> logicalxor(left, right)
-            "<" -> NumericLiteralValue.fromBoolean(left < right, left.position)
-            ">" -> NumericLiteralValue.fromBoolean(left > right, left.position)
-            "<=" -> NumericLiteralValue.fromBoolean(left <= right, left.position)
-            ">=" -> NumericLiteralValue.fromBoolean(left >= right, left.position)
-            "==" -> NumericLiteralValue.fromBoolean(left == right, left.position)
-            "!=" -> NumericLiteralValue.fromBoolean(left != right, left.position)
-            "<<" -> shiftedleft(left, right)
-            ">>" -> shiftedright(left, right)
-            else -> throw FatalAstException("const evaluation for invalid operator $operator")
+        try {
+            return when(operator) {
+                "+" -> plus(left, right)
+                "-" -> minus(left, right)
+                "*" -> multiply(left, right)
+                "/" -> divide(left, right)
+                "%" -> remainder(left, right)
+                "**" -> power(left, right)
+                "&" -> bitwiseand(left, right)
+                "|" -> bitwiseor(left, right)
+                "^" -> bitwisexor(left, right)
+                "and" -> logicaland(left, right)
+                "or" -> logicalor(left, right)
+                "xor" -> logicalxor(left, right)
+                "<" -> NumericLiteralValue.fromBoolean(left < right, left.position)
+                ">" -> NumericLiteralValue.fromBoolean(left > right, left.position)
+                "<=" -> NumericLiteralValue.fromBoolean(left <= right, left.position)
+                ">=" -> NumericLiteralValue.fromBoolean(left >= right, left.position)
+                "==" -> NumericLiteralValue.fromBoolean(left == right, left.position)
+                "!=" -> NumericLiteralValue.fromBoolean(left != right, left.position)
+                "<<" -> shiftedleft(left, right)
+                ">>" -> shiftedright(left, right)
+                else -> throw FatalAstException("const evaluation for invalid operator $operator")
+            }
+        } catch (ax: FatalAstException) {
+            throw ExpressionError(ax.message, left.position)
         }
     }
 

compiler/src/prog8/optimizer/ConstantFoldingOptimizer.kt

@@ -14,7 +14,6 @@ import kotlin.math.pow
 
 
 internal class ConstantFoldingOptimizer(private val program: Program, private val compTarget: ICompilationTarget) : AstWalker() {
-    private val noModifications = emptyList<IAstModification>()
 
     override fun before(memread: DirectMemoryRead, parent: Node): Iterable<IAstModification> {
         // @( &thing )  -->  thing
@@ -107,7 +106,7 @@ internal class ConstantFoldingOptimizer(private val program: Program, private va
             // optimize various simple cases of ** :
             //  optimize away 1 ** x into just 1 and 0 ** x into just 0
             //  optimize 2 ** x into (1<<x)  if both operands are integer.
-            val leftDt = leftconst.inferType(program).typeOrElse(DataType.STRUCT)
+            val leftDt = leftconst.inferType(program).typeOrElse(DataType.UNDEFINED)
             when (leftconst.number.toDouble()) {
                 0.0 -> {
                     val value = NumericLiteralValue(leftDt, 0, expr.position)
@@ -122,11 +121,11 @@ internal class ConstantFoldingOptimizer(private val program: Program, private va
                         val value = NumericLiteralValue(leftDt, 2.0.pow(rightconst.number.toDouble()), expr.position)
                         modifications += IAstModification.ReplaceNode(expr, value, parent)
                     } else {
-                        val rightDt = expr.right.inferType(program).typeOrElse(DataType.STRUCT)
+                        val rightDt = expr.right.inferType(program).typeOrElse(DataType.UNDEFINED)
                         if(leftDt in IntegerDatatypes && rightDt in IntegerDatatypes) {
                             val targetDt =
                                 when (parent) {
-                                    is Assignment -> parent.target.inferType(program).typeOrElse(DataType.STRUCT)
+                                    is Assignment -> parent.target.inferType(program).typeOrElse(DataType.UNDEFINED)
                                     is VarDecl -> parent.datatype
                                     else -> leftDt
                                 }
@@ -188,7 +187,7 @@ internal class ConstantFoldingOptimizer(private val program: Program, private va
         } else {
             val arrayDt = array.guessDatatype(program)
             if (arrayDt.isKnown) {
-                val newArray = array.cast(arrayDt.typeOrElse(DataType.STRUCT))
+                val newArray = array.cast(arrayDt.typeOrElse(DataType.UNDEFINED))
                 if (newArray != null && newArray != array)
                     return listOf(IAstModification.ReplaceNode(array, newArray, parent))
             }

compiler/src/prog8/optimizer/ConstantIdentifierReplacer.kt

@@ -1,13 +1,11 @@
 package prog8.optimizer
 
+import prog8.ast.INameScope
 import prog8.ast.Node
 import prog8.ast.Program
 import prog8.ast.base.*
 import prog8.ast.expressions.*
-import prog8.ast.statements.ArrayIndex
-import prog8.ast.statements.AssignTarget
-import prog8.ast.statements.ForLoop
-import prog8.ast.statements.VarDecl
+import prog8.ast.statements.*
 import prog8.ast.walk.AstWalker
 import prog8.ast.walk.IAstModification
 import prog8.compiler.IErrorReporter
@@ -15,7 +13,6 @@ import prog8.compiler.target.ICompilationTarget
 
 // Fix up the literal value's type to match that of the vardecl
 internal class VarConstantValueTypeAdjuster(private val program: Program, private val errors: IErrorReporter) : AstWalker() {
-    private val noModifications = emptyList<IAstModification>()
 
     override fun after(decl: VarDecl, parent: Node): Iterable<IAstModification> {
         try {
@@ -31,6 +28,28 @@ internal class VarConstantValueTypeAdjuster(private val program: Program, privat
             errors.err(x.message, x.position)
         }
 
+        // move vardecl to the containing subroutine and add initialization assignment in its place if needed
+        if(decl.type == VarDeclType.VAR && decl.datatype in NumericDatatypes) {
+            val subroutine = decl.definingSubroutine() as? INameScope
+            if(subroutine!=null && subroutine!==parent) {
+                val declValue = decl.value
+                decl.value = null
+                decl.allowInitializeWithZero = false
+                return if (declValue == null) {
+                    listOf(
+                        IAstModification.Remove(decl, parent as INameScope),
+                        IAstModification.InsertFirst(decl, subroutine)
+                    )
+                } else {
+                    val target = AssignTarget(IdentifierReference(listOf(decl.name), decl.position), null, null, decl.position)
+                    val assign = Assignment(target, declValue, decl.position)
+                    listOf(
+                        IAstModification.ReplaceNode(decl, assign, parent),
+                        IAstModification.InsertFirst(decl, subroutine)
+                    )
+                }
+            }
+        }
         return noModifications
     }
 }
@@ -40,7 +59,6 @@ internal class VarConstantValueTypeAdjuster(private val program: Program, privat
 // and the array var initializer values and sizes.
 // This is needed because further constant optimizations depend on those.
 internal class ConstantIdentifierReplacer(private val program: Program, private val errors: IErrorReporter, private val compTarget: ICompilationTarget) : AstWalker() {
-    private val noModifications = emptyList<IAstModification>()
 
     override fun after(identifier: IdentifierReference, parent: Node): Iterable<IAstModification> {
         // replace identifiers that refer to const value, with the value itself
@@ -75,7 +93,7 @@ internal class ConstantIdentifierReplacer(private val program: Program, private
     override fun before(decl: VarDecl, parent: Node): Iterable<IAstModification> {
         // the initializer value can't refer to the variable itself (recursive definition)
         // TODO: use call graph for this?
-        if(decl.value?.referencesIdentifier(decl.name) == true || decl.arraysize?.indexVar?.referencesIdentifier(decl.name) == true) {
+        if(decl.value?.referencesIdentifier(decl.name) == true || decl.arraysize?.indexExpr?.referencesIdentifier(decl.name) == true) {
             errors.err("recursive var declaration", decl.position)
             return noModifications
         }
@@ -93,19 +111,6 @@ internal class ConstantIdentifierReplacer(private val program: Program, private
                                 decl
                         ))
                     }
-                } else if(arraysize.constIndex()==null) {
-                    // see if we can calculate the size from other fields
-                    try {
-                        val cval =  arraysize.indexVar?.constValue(program) ?: arraysize.origExpression?.constValue(program)
-                        if (cval != null) {
-                            arraysize.indexVar = null
-                            arraysize.origExpression = null
-                            arraysize.indexNum = cval
-                        }
-                    } catch (x: UndefinedSymbolError) {
-                        errors.err(x.message, x.position)
-                        return noModifications
-                    }
                 }
             }
 
@@ -167,7 +172,7 @@ internal class ConstantIdentifierReplacer(private val program: Program, private
                             else -> {}
                         }
                         // create the array itself, filled with the fillvalue.
-                        val array = Array(size) {fillvalue}.map { NumericLiteralValue(ArrayElementTypes.getValue(decl.datatype), it, numericLv.position) }.toTypedArray<Expression>()
+                        val array = Array(size) {fillvalue}.map { NumericLiteralValue(ArrayToElementTypes.getValue(decl.datatype), it, numericLv.position) }.toTypedArray<Expression>()
                         val refValue = ArrayLiteralValue(InferredTypes.InferredType.known(decl.datatype), array, position = numericLv.position)
                         return listOf(IAstModification.ReplaceNode(decl.value!!, refValue, decl))
                     }
@@ -204,7 +209,6 @@ internal class ConstantIdentifierReplacer(private val program: Program, private
                 }
                 else -> {
                     // nothing to do for this type
-                    // this includes strings and structs
                 }
             }
         }

compiler/src/prog8/optimizer/ExpressionSimplifier.kt

@@ -25,7 +25,6 @@ import kotlin.math.pow
 internal class ExpressionSimplifier(private val program: Program) : AstWalker() {
     private val powersOfTwo = (1..16).map { (2.0).pow(it) }.toSet()
     private val negativePowersOfTwo = powersOfTwo.map { -it }.toSet()
-    private val noModifications = emptyList<IAstModification>()
 
     override fun after(typecast: TypecastExpression, parent: Node): Iterable<IAstModification> {
         val mods = mutableListOf<IAstModification>()
@@ -135,8 +134,8 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
             ))
         }
 
-        val leftDt = leftIDt.typeOrElse(DataType.STRUCT)
-        val rightDt = rightIDt.typeOrElse(DataType.STRUCT)
+        val leftDt = leftIDt.typeOrElse(DataType.UNDEFINED)
+        val rightDt = rightIDt.typeOrElse(DataType.UNDEFINED)
 
         if (expr.operator == "+" || expr.operator == "-"
                 && leftVal == null && rightVal == null
@@ -490,10 +489,10 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
                     val idt = expr.inferType(program)
                     if(!idt.isKnown)
                         throw FatalAstException("unknown dt")
-                    return NumericLiteralValue(idt.typeOrElse(DataType.STRUCT), 0, expr.position)
-                } else if (cv == 2.0) {
+                    return NumericLiteralValue(idt.typeOrElse(DataType.UNDEFINED), 0, expr.position)
+                } else if (cv in powersOfTwo) {
                     expr.operator = "&"
-                    expr.right = NumericLiteralValue.optimalInteger(1, expr.position)
+                    expr.right = NumericLiteralValue.optimalInteger(cv!!.toInt()-1, expr.position)
                     return null
                 }
             }
@@ -514,7 +513,7 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
             val leftIDt = expr.left.inferType(program)
             if (!leftIDt.isKnown)
                 return null
-            val leftDt = leftIDt.typeOrElse(DataType.STRUCT)
+            val leftDt = leftIDt.typeOrElse(DataType.UNDEFINED)
             when (cv) {
                 -1.0 -> {
                     //  '/' -> -left
@@ -591,14 +590,14 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
                     return expr2.left
                 }
                 in powersOfTwo -> {
-                    if (leftValue.inferType(program).typeOrElse(DataType.STRUCT) in IntegerDatatypes) {
+                    if (leftValue.inferType(program).isInteger()) {
                         // times a power of two => shift left
                         val numshifts = log2(cv).toInt()
                         return BinaryExpression(expr2.left, "<<", NumericLiteralValue.optimalInteger(numshifts, expr.position), expr.position)
                     }
                 }
                 in negativePowersOfTwo -> {
-                    if (leftValue.inferType(program).typeOrElse(DataType.STRUCT) in IntegerDatatypes) {
+                    if (leftValue.inferType(program).isInteger()) {
                         // times a negative power of two => negate, then shift left
                         val numshifts = log2(-cv).toInt()
                         return BinaryExpression(PrefixExpression("-", expr2.left, expr.position), "<<", NumericLiteralValue.optimalInteger(numshifts, expr.position), expr.position)
@@ -622,7 +621,7 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
         val targetIDt = expr.left.inferType(program)
         if(!targetIDt.isKnown)
             throw FatalAstException("unknown dt")
-        when (val targetDt = targetIDt.typeOrElse(DataType.STRUCT)) {
+        when (val targetDt = targetIDt.typeOrElse(DataType.UNDEFINED)) {
             DataType.UBYTE, DataType.BYTE -> {
                 if (amount >= 8) {
                     return NumericLiteralValue(targetDt, 0, expr.position)
@@ -657,7 +656,7 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
         val idt = expr.left.inferType(program)
         if(!idt.isKnown)
             throw FatalAstException("unknown dt")
-        when (idt.typeOrElse(DataType.STRUCT)) {
+        when (idt.typeOrElse(DataType.UNDEFINED)) {
             DataType.UBYTE -> {
                 if (amount >= 8) {
                     return NumericLiteralValue.optimalInteger(0, expr.position)

compiler/src/prog8/optimizer/Extensions.kt

@@ -4,31 +4,30 @@ import prog8.ast.IBuiltinFunctions
 import prog8.ast.Program
 import prog8.compiler.IErrorReporter
 import prog8.compiler.target.ICompilationTarget
-import java.nio.file.Path
 
 
 internal fun Program.constantFold(errors: IErrorReporter, compTarget: ICompilationTarget) {
     val valuetypefixer = VarConstantValueTypeAdjuster(this, errors)
     valuetypefixer.visit(this)
-    if(errors.isEmpty()) {
+    if(errors.noErrors()) {
         valuetypefixer.applyModifications()
 
         val replacer = ConstantIdentifierReplacer(this, errors, compTarget)
         replacer.visit(this)
-        if (errors.isEmpty()) {
+        if (errors.noErrors()) {
             replacer.applyModifications()
 
             valuetypefixer.visit(this)
-            if(errors.isEmpty()) {
+            if(errors.noErrors()) {
                 valuetypefixer.applyModifications()
 
                 val optimizer = ConstantFoldingOptimizer(this, compTarget)
                 optimizer.visit(this)
-                while (errors.isEmpty() && optimizer.applyModifications() > 0) {
+                while (errors.noErrors() && optimizer.applyModifications() > 0) {
                     optimizer.visit(this)
                 }
 
-                if (errors.isEmpty()) {
+                if (errors.noErrors()) {
                     replacer.visit(this)
                     replacer.applyModifications()
                 }
@@ -36,16 +35,15 @@ internal fun Program.constantFold(errors: IErrorReporter, compTarget: ICompilati
         }
     }
 
-    if(errors.isEmpty())
+    if(errors.noErrors())
         modules.forEach { it.linkParents(namespace) }   // re-link in final configuration
 }
 
 
 internal fun Program.optimizeStatements(errors: IErrorReporter,
                                         functions: IBuiltinFunctions,
-                                        compTarget: ICompilationTarget,
-                                        asmFileLoader: (filename: String, source: Path)->String): Int {
-    val optimizer = StatementOptimizer(this, errors, functions, compTarget, asmFileLoader)
+                                        compTarget: ICompilationTarget): Int {
+    val optimizer = StatementOptimizer(this, errors, functions, compTarget)
     optimizer.visit(this)
     val optimizationCount = optimizer.applyModifications()
 

compiler/src/prog8/optimizer/StatementOptimizer.kt

@@ -12,67 +12,30 @@ import prog8.ast.walk.IAstModification
 import prog8.ast.walk.IAstVisitor
 import prog8.compiler.IErrorReporter
 import prog8.compiler.target.ICompilationTarget
-import java.nio.file.Path
 import kotlin.math.floor
 
+internal const val retvarName = "prog8_retval"
+
 
 internal class StatementOptimizer(private val program: Program,
                                   private val errors: IErrorReporter,
                                   private val functions: IBuiltinFunctions,
-                                  private val compTarget: ICompilationTarget,
-                                  asmFileLoader: (filename: String, source: Path)->String
-) : AstWalker() {
+                                  private val compTarget: ICompilationTarget) : AstWalker() {
 
-    private val noModifications = emptyList<IAstModification>()
-    private val callgraph = CallGraph(program, asmFileLoader)
+    private val subsThatNeedReturnVariable = mutableSetOf<Triple<INameScope, DataType, Position>>()
 
-    override fun after(block: Block, parent: Node): Iterable<IAstModification> {
-        if("force_output" !in block.options()) {
-            if (block.containsNoCodeNorVars()) {
-                if(block.name != program.internedStringsModuleName)
-                    errors.warn("removing empty block '${block.name}'", block.position)
-                return listOf(IAstModification.Remove(block, parent as INameScope))
-            }
-
-            if (block !in callgraph.usedSymbols) {
-                errors.warn("removing unused block '${block.name}'", block.position)
-                return listOf(IAstModification.Remove(block, parent as INameScope))
-            }
-        }
-        return noModifications
-    }
 
     override fun after(subroutine: Subroutine, parent: Node): Iterable<IAstModification> {
-        val forceOutput = "force_output" in subroutine.definingBlock().options()
-        if(subroutine.asmAddress==null && !forceOutput) {
-            if(subroutine.containsNoCodeNorVars() && !subroutine.inline) {
-                errors.warn("removing empty subroutine '${subroutine.name}'", subroutine.position)
-                val removals = callgraph.calledBy.getValue(subroutine).map {
-                    IAstModification.Remove(it, it.definingScope())
-                }.toMutableList()
-                removals += IAstModification.Remove(subroutine, subroutine.definingScope())
-                return removals
-            }
+        for(returnvar in subsThatNeedReturnVariable) {
+            val decl = VarDecl(VarDeclType.VAR, returnvar.second, ZeropageWish.DONTCARE, null, retvarName, null,
+                isArray = false,
+                autogeneratedDontRemove = true,
+                sharedWithAsm = false,
+                position = returnvar.third
+            )
+            returnvar.first.statements.add(0, decl)
         }
-
-        if(subroutine !in callgraph.usedSymbols && !forceOutput) {
-            if(!subroutine.isAsmSubroutine)
-                errors.warn("removing unused subroutine '${subroutine.name}'", subroutine.position)
-            return listOf(IAstModification.Remove(subroutine, subroutine.definingScope()))
-        }
-
-        return noModifications
-    }
-
-    override fun after(decl: VarDecl, parent: Node): Iterable<IAstModification> {
-        val forceOutput = "force_output" in decl.definingBlock().options()
-        if(decl !in callgraph.usedSymbols && !forceOutput) {
-            if(decl.type == VarDeclType.VAR)
-                errors.warn("removing unused variable '${decl.name}'", decl.position)
-
-            return listOf(IAstModification.Remove(decl, decl.definingScope()))
-        }
-
+        subsThatNeedReturnVariable.clear()
         return noModifications
     }
 
@@ -86,6 +49,7 @@ internal class StatementOptimizer(private val program: Program,
         }
 
         // printing a literal string of just 2 or 1 characters is replaced by directly outputting those characters
+        // only do this optimization if the arg is a known-constant string literal instead of a user defined variable.
         if(functionCallStatement.target.nameInSource==listOf("txt", "print")) {
             val arg = functionCallStatement.args.single()
             val stringVar: IdentifierReference? = if(arg is AddressOf) {
@@ -93,30 +57,29 @@ internal class StatementOptimizer(private val program: Program,
             } else {
                 arg as? IdentifierReference
             }
-            if(stringVar!=null) {
-                val vardecl = stringVar.targetVarDecl(program)!!
-                val string = vardecl.value as? StringLiteralValue
+            if(stringVar!=null && stringVar.wasStringLiteral(program)) {
+                val string = stringVar.targetVarDecl(program)?.value as? StringLiteralValue
                 if(string!=null) {
                     val pos = functionCallStatement.position
                     if (string.value.length == 1) {
                         val firstCharEncoded = compTarget.encodeString(string.value, string.altEncoding)[0]
                         val chrout = FunctionCallStatement(
-                                IdentifierReference(listOf("txt", "chrout"), pos),
-                                mutableListOf(NumericLiteralValue(DataType.UBYTE, firstCharEncoded.toInt(), pos)),
-                                functionCallStatement.void, pos
+                            IdentifierReference(listOf("txt", "chrout"), pos),
+                            mutableListOf(NumericLiteralValue(DataType.UBYTE, firstCharEncoded.toInt(), pos)),
+                            functionCallStatement.void, pos
                         )
                         return listOf(IAstModification.ReplaceNode(functionCallStatement, chrout, parent))
                     } else if (string.value.length == 2) {
                         val firstTwoCharsEncoded = compTarget.encodeString(string.value.take(2), string.altEncoding)
                         val chrout1 = FunctionCallStatement(
-                                IdentifierReference(listOf("txt", "chrout"), pos),
-                                mutableListOf(NumericLiteralValue(DataType.UBYTE, firstTwoCharsEncoded[0].toInt(), pos)),
-                                functionCallStatement.void, pos
+                            IdentifierReference(listOf("txt", "chrout"), pos),
+                            mutableListOf(NumericLiteralValue(DataType.UBYTE, firstTwoCharsEncoded[0].toInt(), pos)),
+                            functionCallStatement.void, pos
                         )
                         val chrout2 = FunctionCallStatement(
-                                IdentifierReference(listOf("txt", "chrout"), pos),
-                                mutableListOf(NumericLiteralValue(DataType.UBYTE, firstTwoCharsEncoded[1].toInt(), pos)),
-                                functionCallStatement.void, pos
+                            IdentifierReference(listOf("txt", "chrout"), pos),
+                            mutableListOf(NumericLiteralValue(DataType.UBYTE, firstTwoCharsEncoded[1].toInt(), pos)),
+                            functionCallStatement.void, pos
                         )
                         return listOf(
                             IAstModification.InsertBefore(functionCallStatement, chrout1, parent as INameScope),
@@ -375,7 +338,7 @@ internal class StatementOptimizer(private val program: Program,
             throw FatalAstException("can't infer type of assignment target")
 
         // optimize binary expressions a bit
-        val targetDt = targetIDt.typeOrElse(DataType.STRUCT)
+        val targetDt = targetIDt.typeOrElse(DataType.UNDEFINED)
         val bexpr=assignment.value as? BinaryExpression
         if(bexpr!=null) {
             val rightCv = bexpr.right.constValue(program)?.number?.toDouble()
@@ -393,7 +356,7 @@ internal class StatementOptimizer(private val program: Program,
                                 // replace by several INCs if it's not a memory address (inc on a memory mapped register doesn't work very well)
                                 val incs = AnonymousScope(mutableListOf(), assignment.position)
                                 repeat(rightCv.toInt()) {
-                                    incs.statements.add(PostIncrDecr(assignment.target, "++", assignment.position))
+                                    incs.statements.add(PostIncrDecr(assignment.target.copy(), "++", assignment.position))
                                 }
                                 return listOf(IAstModification.ReplaceNode(assignment, incs, parent))
                             }
@@ -407,7 +370,7 @@ internal class StatementOptimizer(private val program: Program,
                                 // replace by several DECs if it's not a memory address (dec on a memory mapped register doesn't work very well)
                                 val decs = AnonymousScope(mutableListOf(), assignment.position)
                                 repeat(rightCv.toInt()) {
-                                    decs.statements.add(PostIncrDecr(assignment.target, "--", assignment.position))
+                                    decs.statements.add(PostIncrDecr(assignment.target.copy(), "--", assignment.position))
                                 }
                                 return listOf(IAstModification.ReplaceNode(assignment, decs, parent))
                             }
@@ -435,21 +398,17 @@ internal class StatementOptimizer(private val program: Program,
     }
 
     override fun after(returnStmt: Return, parent: Node): Iterable<IAstModification> {
-        fun returnViaIntermediary(value: Expression): Iterable<IAstModification>? {
-            val returnDt = returnStmt.definingSubroutine()!!.returntypes.single()
+        fun returnViaIntermediaryVar(value: Expression): Iterable<IAstModification>? {
+            val subr = returnStmt.definingSubroutine()!!
+            val returnDt = subr.returntypes.single()
             if (returnDt in IntegerDatatypes) {
-                // first assign to intermediary, then return that register
-                val returnValueIntermediary =
-                    when(returnDt) {
-                        DataType.UBYTE -> IdentifierReference(listOf("prog8_lib", "retval_interm_ub"), returnStmt.position)
-                        DataType.BYTE -> IdentifierReference(listOf("prog8_lib", "retval_interm_b"), returnStmt.position)
-                        DataType.UWORD -> IdentifierReference(listOf("prog8_lib", "retval_interm_uw"), returnStmt.position)
-                        DataType.WORD -> IdentifierReference(listOf("prog8_lib", "retval_interm_w"), returnStmt.position)
-                        else -> throw FatalAstException("weird return dt")
-                    }
-                val tgt = AssignTarget(returnValueIntermediary, null, null, returnStmt.position)
+                // first assign to intermediary variable, then return that
+                subsThatNeedReturnVariable.add(Triple(subr, returnDt, returnStmt.position))
+                val returnValueIntermediary1 = IdentifierReference(listOf(retvarName), returnStmt.position)
+                val returnValueIntermediary2 = IdentifierReference(listOf(retvarName), returnStmt.position)
+                val tgt = AssignTarget(returnValueIntermediary1, null, null, returnStmt.position)
                 val assign = Assignment(tgt, value, returnStmt.position)
-                val returnReplacement = Return(returnValueIntermediary, returnStmt.position)
+                val returnReplacement = Return(returnValueIntermediary2, returnStmt.position)
                 return listOf(
                     IAstModification.InsertBefore(returnStmt, assign, parent as INameScope),
                     IAstModification.ReplaceNode(returnStmt, returnReplacement, parent)
@@ -460,12 +419,12 @@ internal class StatementOptimizer(private val program: Program,
 
         when(returnStmt.value) {
             is PrefixExpression -> {
-                val mod = returnViaIntermediary(returnStmt.value!!)
+                val mod = returnViaIntermediaryVar(returnStmt.value!!)
                 if(mod!=null)
                     return mod
             }
             is BinaryExpression -> {
-                val mod = returnViaIntermediary(returnStmt.value!!)
+                val mod = returnViaIntermediaryVar(returnStmt.value!!)
                 if(mod!=null)
                     return mod
             }

compiler/src/prog8/optimizer/SubroutineInliner.kt

@@ -0,0 +1,96 @@
+package prog8.optimizer
+
+import prog8.ast.IFunctionCall
+import prog8.ast.Node
+import prog8.ast.Program
+import prog8.ast.base.Position
+import prog8.ast.expressions.FunctionCall
+import prog8.ast.expressions.IdentifierReference
+import prog8.ast.statements.*
+import prog8.ast.walk.AstWalker
+import prog8.ast.walk.IAstModification
+import prog8.compiler.CompilationOptions
+import prog8.compiler.IErrorReporter
+
+
+internal class SubroutineInliner(private val program: Program, val errors: IErrorReporter, private val compilerOptions: CompilationOptions): AstWalker() {
+    private var callsToInlinedSubroutines = mutableListOf<Pair<IFunctionCall, Node>>()
+
+    fun fixCallsToInlinedSubroutines() {
+        for((call, parent) in callsToInlinedSubroutines) {
+            val sub = call.target.targetSubroutine(program)!!
+            val intermediateReturnValueVar = sub.statements.filterIsInstance<VarDecl>().singleOrNull { it.name.endsWith(retvarName) }
+            if(intermediateReturnValueVar!=null) {
+                val scope = parent.definingScope()
+                if(!scope.statements.filterIsInstance<VarDecl>().any { it.name==intermediateReturnValueVar.name}) {
+                    val decl = intermediateReturnValueVar.copy()
+                    scope.statements.add(0, decl)
+                    decl.linkParents(scope as Node)
+                }
+            }
+        }
+    }
+
+    override fun after(subroutine: Subroutine, parent: Node): Iterable<IAstModification> {
+        return if(compilerOptions.optimize && subroutine.inline && !subroutine.isAsmSubroutine)
+            annotateInlinedSubroutineIdentifiers(subroutine)
+        else
+            noModifications
+    }
+
+    override fun after(functionCallStatement: FunctionCallStatement, parent: Node): Iterable<IAstModification> {
+        return after(functionCallStatement as IFunctionCall, parent, functionCallStatement.position)
+    }
+
+    override fun after(functionCall: FunctionCall, parent: Node): Iterable<IAstModification> {
+        return after(functionCall as IFunctionCall, parent, functionCall.position)
+    }
+
+    private fun after(functionCall: IFunctionCall, parent: Node, position: Position): Iterable<IAstModification> {
+        val sub = functionCall.target.targetSubroutine(program)
+        if(sub != null && compilerOptions.optimize && sub.inline && !sub.isAsmSubroutine)
+            callsToInlinedSubroutines.add(Pair(functionCall, parent))
+
+        return noModifications
+    }
+
+    private fun annotateInlinedSubroutineIdentifiers(sub: Subroutine): List<IAstModification> {
+        // this adds name prefixes to the identifiers used in the subroutine,
+        // so that the statements can be inlined (=copied) in the call site and still reference
+        // the correct symbols as seen from the scope of the subroutine.
+
+        class Annotator: AstWalker() {
+            var numReturns=0
+
+            override fun before(identifier: IdentifierReference, parent: Node): Iterable<IAstModification> {
+                val stmt = identifier.targetStatement(program)!!
+                if(stmt is BuiltinFunctionStatementPlaceholder)
+                    return noModifications
+
+                val prefixed = stmt.makeScopedName(identifier.nameInSource.last()).split('.')
+                val withPrefix = IdentifierReference(prefixed, identifier.position)
+                return listOf(IAstModification.ReplaceNode(identifier, withPrefix, parent))
+            }
+
+            override fun before(returnStmt: Return, parent: Node): Iterable<IAstModification> {
+                numReturns++
+                if(parent !== sub || sub.indexOfChild(returnStmt)<sub.statements.size-1)
+                    errors.err("return statement must be the very last statement in the inlined subroutine", sub.position)
+                return noModifications
+            }
+
+            fun theModifications(): List<IAstModification> {
+                return this.modifications.map { it.first }.toList()
+            }
+        }
+
+        val annotator = Annotator()
+        sub.accept(annotator, sub.parent)
+        if(annotator.numReturns>1) {
+            errors.err("inlined subroutine can only have one return statement", sub.position)
+            return noModifications
+        }
+        return annotator.theModifications()
+    }
+
+}

compiler/src/prog8/optimizer/UnusedCodeRemover.kt

@@ -1,8 +1,7 @@
 package prog8.optimizer
 
-import prog8.ast.INameScope
-import prog8.ast.Node
-import prog8.ast.Program
+import prog8.ast.*
+import prog8.ast.base.VarDeclType
 import prog8.ast.expressions.BinaryExpression
 import prog8.ast.expressions.FunctionCall
 import prog8.ast.expressions.PrefixExpression
@@ -12,44 +11,21 @@ import prog8.ast.walk.AstWalker
 import prog8.ast.walk.IAstModification
 import prog8.compiler.IErrorReporter
 import prog8.compiler.target.ICompilationTarget
-import java.nio.file.Path
 
 
 internal class UnusedCodeRemover(private val program: Program,
                                  private val errors: IErrorReporter,
-                                 private val compTarget: ICompilationTarget,
-                                 private val asmFileLoader: (filename: String, source: Path)->String): AstWalker() {
+                                 private val compTarget: ICompilationTarget): AstWalker() {
 
-    override fun before(program: Program, parent: Node): Iterable<IAstModification> {
-        val callgraph = CallGraph(program, asmFileLoader)
-        val removals = mutableListOf<IAstModification>()
+    private val callgraph = CallGraph(program)
 
-        // remove all subroutines that aren't called, or are empty
-        val entrypoint = program.entrypoint()
-        program.modules.forEach {
-            callgraph.forAllSubroutines(it) { sub ->
-                val forceOutput = "force_output" in sub.definingBlock().options()
-                if (sub !== entrypoint && !forceOutput && !sub.isAsmSubroutine && (callgraph.calledBy[sub].isNullOrEmpty() || sub.containsNoCodeNorVars())) {
-                    removals.add(IAstModification.Remove(sub, sub.definingScope()))
-                }
-            }
-        }
-
-        program.modules.flatMap { it.statements }.filterIsInstance<Block>().forEach { block ->
-            if (block.containsNoCodeNorVars() && "force_output" !in block.options())
-                removals.add(IAstModification.Remove(block, block.definingScope()))
-        }
-
-        // remove modules that are not imported, or are empty (unless it's a library modules)
-        program.modules.forEach {
-            if (!it.isLibraryModule && (it.importedBy.isEmpty() || it.containsNoCodeNorVars()))
-                removals.add(IAstModification.Remove(it, it.definingScope()))
-        }
-
-        return removals
+    override fun before(module: Module, parent: Node): Iterable<IAstModification> {
+        return if (!module.isLibraryModule && (module.containsNoCodeNorVars() || callgraph.unused(module)))
+            listOf(IAstModification.Remove(module, module.definingScope()))
+        else
+            noModifications
     }
 
-
     override fun before(breakStmt: Break, parent: Node): Iterable<IAstModification> {
         reportUnreachable(breakStmt, parent as INameScope)
         return emptyList()
@@ -73,7 +49,7 @@ internal class UnusedCodeRemover(private val program: Program,
 
     private fun reportUnreachable(stmt: Statement, parent: INameScope) {
         when(val next = parent.nextSibling(stmt)) {
-            null, is Label, is Directive, is VarDecl, is InlineAssembly, is Subroutine, is StructDecl -> {}
+            null, is Label, is Directive, is VarDecl, is InlineAssembly, is Subroutine -> {}
             else -> errors.warn("unreachable code", next.position)
         }
     }
@@ -84,15 +60,60 @@ internal class UnusedCodeRemover(private val program: Program,
     }
 
     override fun after(block: Block, parent: Node): Iterable<IAstModification> {
+        if("force_output" !in block.options()) {
+            if (block.containsNoCodeNorVars()) {
+                if(block.name != internedStringsModuleName)
+                    errors.warn("removing unused block '${block.name}'", block.position)
+                return listOf(IAstModification.Remove(block, parent as INameScope))
+            }
+            if(callgraph.unused(block)) {
+                errors.warn("removing unused block '${block.name}'", block.position)
+                return listOf(IAstModification.Remove(block, parent as INameScope))
+            }
+        }
+
         val removeDoubleAssignments = deduplicateAssignments(block.statements)
         return removeDoubleAssignments.map { IAstModification.Remove(it, block) }
     }
 
     override fun after(subroutine: Subroutine, parent: Node): Iterable<IAstModification> {
+        val forceOutput = "force_output" in subroutine.definingBlock().options()
+        if (subroutine !== program.entrypoint() && !forceOutput && !subroutine.inline && !subroutine.isAsmSubroutine) {
+            if(callgraph.unused(subroutine)) {
+                if(!subroutine.definingModule().isLibraryModule)
+                    errors.warn("removing unused subroutine '${subroutine.name}'", subroutine.position)
+                return listOf(IAstModification.Remove(subroutine, subroutine.definingScope()))
+            }
+            if(subroutine.containsNoCodeNorVars()) {
+                if(!subroutine.definingModule().isLibraryModule)
+                    errors.warn("removing empty subroutine '${subroutine.name}'", subroutine.position)
+                val removals = mutableListOf(IAstModification.Remove(subroutine, subroutine.definingScope()))
+                callgraph.calledBy[subroutine]?.let {
+                    for(node in it)
+                        removals.add(IAstModification.Remove(node, node.definingScope()))
+                }
+                return removals
+            }
+        }
+
         val removeDoubleAssignments = deduplicateAssignments(subroutine.statements)
         return removeDoubleAssignments.map { IAstModification.Remove(it, subroutine) }
     }
 
+    override fun after(decl: VarDecl, parent: Node): Iterable<IAstModification> {
+        if(decl.type==VarDeclType.VAR) {
+            val forceOutput = "force_output" in decl.definingBlock().options()
+            if (!forceOutput && !decl.autogeneratedDontRemove && !decl.sharedWithAsm && !decl.definingBlock().isInLibrary) {
+                if (callgraph.unused(decl)) {
+                    errors.warn("removing unused variable '${decl.name}'", decl.position)
+                    return listOf(IAstModification.Remove(decl, decl.definingScope()))
+                }
+            }
+        }
+
+        return noModifications
+    }
+
     private fun deduplicateAssignments(statements: List<Statement>): List<Assignment> {
         // removes 'duplicate' assignments that assign the same target directly after another
         val linesToRemove = mutableListOf<Assignment>()

compiler/test/UnitTests.kt

@@ -19,9 +19,8 @@ import prog8.compiler.target.c64.C64MachineDefinition.C64Zeropage
 import prog8.compiler.target.c64.C64MachineDefinition.FLOAT_MAX_NEGATIVE
 import prog8.compiler.target.c64.C64MachineDefinition.FLOAT_MAX_POSITIVE
 import prog8.compiler.target.c64.C64MachineDefinition.Mflpt5
-import prog8.compiler.target.c64.Petscii
+import prog8.compiler.target.cbm.Petscii
 import prog8.compiler.target.cx16.CX16MachineDefinition.CX16Zeropage
-import java.io.CharConversionException
 import java.nio.file.Path
 import kotlin.test.*
 
@@ -180,28 +179,48 @@ class TestC64Zeropage {
     fun testZpDontuse() {
         val zp = C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.DONTUSE, emptyList(), false, false, C64Target))
         println(zp.free)
-        assertEquals(0, zp.available())
+        assertEquals(0, zp.availableBytes())
         assertFailsWith<CompilerException> {
             zp.allocate("", DataType.BYTE, null, errors)
         }
     }
 
     @Test
-    fun testFreeSpaces() {
+    fun testFreeSpacesBytes() {
         val zp1 = C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.BASICSAFE, emptyList(), true, false, C64Target))
-        assertEquals(18, zp1.available())
+        assertEquals(18, zp1.availableBytes())
         val zp2 = C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.FLOATSAFE, emptyList(), false, false, C64Target))
-        assertEquals(89, zp2.available())
+        assertEquals(85, zp2.availableBytes())
         val zp3 = C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.KERNALSAFE, emptyList(), false, false, C64Target))
-        assertEquals(125, zp3.available())
+        assertEquals(125, zp3.availableBytes())
         val zp4 = C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.FULL, emptyList(), false, false, C64Target))
-        assertEquals(238, zp4.available())
+        assertEquals(238, zp4.availableBytes())
+        zp4.allocate("test", DataType.UBYTE, null, errors)
+        assertEquals(237, zp4.availableBytes())
+        zp4.allocate("test2", DataType.UBYTE, null, errors)
+        assertEquals(236, zp4.availableBytes())
+    }
+
+    @Test
+    fun testFreeSpacesWords() {
+        val zp1 = C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.BASICSAFE, emptyList(), true, false, C64Target))
+        assertEquals(6, zp1.availableWords())
+        val zp2 = C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.FLOATSAFE, emptyList(), false, false, C64Target))
+        assertEquals(38, zp2.availableWords())
+        val zp3 = C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.KERNALSAFE, emptyList(), false, false, C64Target))
+        assertEquals(57, zp3.availableWords())
+        val zp4 = C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.FULL, emptyList(), false, false, C64Target))
+        assertEquals(116, zp4.availableWords())
+        zp4.allocate("test", DataType.UWORD, null, errors)
+        assertEquals(115, zp4.availableWords())
+        zp4.allocate("test2", DataType.UWORD, null, errors)
+        assertEquals(114, zp4.availableWords())
     }
 
     @Test
     fun testReservedSpace() {
         val zp1 = C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.FULL, emptyList(), false, false, C64Target))
-        assertEquals(238, zp1.available())
+        assertEquals(238, zp1.availableBytes())
         assertTrue(50 in zp1.free)
         assertTrue(100 in zp1.free)
         assertTrue(49 in zp1.free)
@@ -210,7 +229,7 @@ class TestC64Zeropage {
         assertTrue(255 in zp1.free)
         assertTrue(199 in zp1.free)
         val zp2 = C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.FULL, listOf(50 .. 100, 200..255), false, false, C64Target))
-        assertEquals(139, zp2.available())
+        assertEquals(139, zp2.availableBytes())
         assertFalse(50 in zp2.free)
         assertFalse(100 in zp2.free)
         assertTrue(49 in zp2.free)
@@ -223,18 +242,22 @@ class TestC64Zeropage {
     @Test
     fun testBasicsafeAllocation() {
         val zp = C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.BASICSAFE, emptyList(), true, false, C64Target))
-        assertEquals(18, zp.available())
+        assertEquals(18, zp.availableBytes())
+        assertTrue(zp.hasByteAvailable())
+        assertTrue(zp.hasWordAvailable())
 
         assertFailsWith<ZeropageDepletedError> {
             // in regular zp there aren't 5 sequential bytes free
             zp.allocate("", DataType.FLOAT, null, errors)
         }
 
-        for (i in 0 until zp.available()) {
+        for (i in 0 until zp.availableBytes()) {
             val loc = zp.allocate("", DataType.UBYTE, null, errors)
             assertTrue(loc > 0)
         }
-        assertEquals(0, zp.available())
+        assertEquals(0, zp.availableBytes())
+        assertFalse(zp.hasByteAvailable())
+        assertFalse(zp.hasWordAvailable())
         assertFailsWith<ZeropageDepletedError> {
             zp.allocate("", DataType.UBYTE, null, errors)
         }
@@ -246,16 +269,18 @@ class TestC64Zeropage {
     @Test
     fun testFullAllocation() {
         val zp = C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.FULL, emptyList(), false, false, C64Target))
-        assertEquals(238, zp.available())
+        assertEquals(238, zp.availableBytes())
+        assertTrue(zp.hasByteAvailable())
+        assertTrue(zp.hasWordAvailable())
         val loc = zp.allocate("", DataType.UWORD, null, errors)
         assertTrue(loc > 3)
         assertFalse(loc in zp.free)
-        val num = zp.available() / 2
+        val num = zp.availableBytes() / 2
 
         for(i in 0..num-4) {
             zp.allocate("", DataType.UWORD, null, errors)
         }
-        assertEquals(6,zp.available())
+        assertEquals(6,zp.availableBytes())
 
         assertFailsWith<ZeropageDepletedError> {
             // can't allocate because no more sequential bytes, only fragmented
@@ -266,7 +291,9 @@ class TestC64Zeropage {
             zp.allocate("", DataType.UBYTE, null, errors)
         }
 
-        assertEquals(0, zp.available())
+        assertEquals(0, zp.availableBytes())
+        assertFalse(zp.hasByteAvailable())
+        assertFalse(zp.hasWordAvailable())
         assertFailsWith<ZeropageDepletedError> {
             // no more space
             zp.allocate("", DataType.UBYTE, null, errors)
@@ -276,7 +303,7 @@ class TestC64Zeropage {
     @Test
     fun testEfficientAllocation() {
         val zp = C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.BASICSAFE, emptyList(),  true, false, C64Target))
-        assertEquals(18, zp.available())
+        assertEquals(18, zp.availableBytes())
         assertEquals(0x04, zp.allocate("", DataType.WORD, null, errors))
         assertEquals(0x06, zp.allocate("", DataType.UBYTE, null, errors))
         assertEquals(0x0a, zp.allocate("", DataType.UBYTE, null, errors))
@@ -289,7 +316,7 @@ class TestC64Zeropage {
         assertEquals(0x92, zp.allocate("", DataType.UBYTE, null, errors))
         assertEquals(0x96, zp.allocate("", DataType.UBYTE, null, errors))
         assertEquals(0xf9, zp.allocate("", DataType.UBYTE, null, errors))
-        assertEquals(0, zp.available())
+        assertEquals(0, zp.availableBytes())
     }
 
     @Test
@@ -302,6 +329,8 @@ class TestC64Zeropage {
 
 @TestInstance(TestInstance.Lifecycle.PER_CLASS)
 class TestCx16Zeropage {
+    private val errors = ErrorReporter()
+
     @Test
     fun testReservedLocations() {
         val zp = CX16Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.BASICSAFE, emptyList(), false, false, Cx16Target))
@@ -309,19 +338,37 @@ class TestCx16Zeropage {
     }
 
     @Test
-    fun testFreeSpaces() {
+    fun testFreeSpacesBytes() {
         val zp1 = CX16Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.BASICSAFE, emptyList(), true, false, Cx16Target))
-        assertEquals(88, zp1.available())
-        val zp3 = CX16Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.KERNALSAFE, emptyList(), false, false, Cx16Target))
-        assertEquals(175, zp3.available())
-        val zp4 = CX16Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.FULL, emptyList(), false, false, Cx16Target))
-        assertEquals(216, zp4.available())
+        assertEquals(88, zp1.availableBytes())
+        val zp2 = CX16Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.KERNALSAFE, emptyList(), false, false, Cx16Target))
+        assertEquals(175, zp2.availableBytes())
+        val zp3 = CX16Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.FULL, emptyList(), false, false, Cx16Target))
+        assertEquals(216, zp3.availableBytes())
+        zp3.allocate("test", DataType.UBYTE, null, errors)
+        assertEquals(215, zp3.availableBytes())
+        zp3.allocate("test2", DataType.UBYTE, null, errors)
+        assertEquals(214, zp3.availableBytes())
+    }
+
+    @Test
+    fun testFreeSpacesWords() {
+        val zp1 = CX16Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.FULL, emptyList(), false, false, Cx16Target))
+        assertEquals(108, zp1.availableWords())
+        val zp2 = CX16Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.KERNALSAFE, emptyList(), false, false, Cx16Target))
+        assertEquals(87, zp2.availableWords())
+        val zp3 = CX16Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.BASICSAFE, emptyList(), true, false, Cx16Target))
+        assertEquals(44, zp3.availableWords())
+        zp3.allocate("test", DataType.UWORD, null, errors)
+        assertEquals(43, zp3.availableWords())
+        zp3.allocate("test2", DataType.UWORD, null, errors)
+        assertEquals(42, zp3.availableWords())
     }
 
     @Test
     fun testReservedSpace() {
         val zp1 = CX16Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.FULL, emptyList(), false, false, Cx16Target))
-        assertEquals(216, zp1.available())
+        assertEquals(216, zp1.availableBytes())
         assertTrue(0x22 in zp1.free)
         assertTrue(0x80 in zp1.free)
         assertTrue(0xff in zp1.free)
@@ -348,8 +395,8 @@ class TestPetscii {
                 listOf<Short>(72, 69, 76, 76, 79, 32, 0xd7, 0xcf, 0xd2, 0xcc, 0xc4, 32, 49, 50, 51, 32, 64, 33, 0x5c)))
         assertThat(Petscii.encodePetscii("\uf11a", true), equalTo(listOf<Short>(0x12)))   // reverse vid
         assertThat(Petscii.encodePetscii("✓", true), equalTo(listOf<Short>(0xfa)))
-        assertFailsWith<CharConversionException> { Petscii.encodePetscii("π", true) }
-        assertFailsWith<CharConversionException> { Petscii.encodePetscii("♥", true) }
+        assertThat("expect lowercase error fallback", Petscii.encodePetscii("π", true), equalTo(listOf<Short>(255)))
+        assertThat("expect lowercase error fallback", Petscii.encodePetscii("♥", true), equalTo(listOf<Short>(0xd3)))
 
         assertThat(Petscii.decodePetscii(listOf(72, 0xd7, 0x5c, 0xfa, 0x12), true), equalTo("hW£✓\uF11A"))
         assertFailsWith<ArrayIndexOutOfBoundsException> { Petscii.decodePetscii(listOf(-1), true) }
@@ -363,7 +410,7 @@ class TestPetscii {
         assertThat(Petscii.encodePetscii("\uf11a"), equalTo(listOf<Short>(0x12)))   // reverse vid
         assertThat(Petscii.encodePetscii("♥"), equalTo(listOf<Short>(0xd3)))
         assertThat(Petscii.encodePetscii("π"), equalTo(listOf<Short>(0xff)))
-        assertFailsWith<CharConversionException> { Petscii.encodePetscii("✓") }
+        assertThat("expecting fallback", Petscii.encodePetscii("✓"), equalTo(listOf<Short>(250)))
 
         assertThat(Petscii.decodePetscii(listOf(72, 0x5c, 0xd3, 0xff)), equalTo("H£♥π"))
         assertFailsWith<ArrayIndexOutOfBoundsException> { Petscii.decodePetscii(listOf(-1)) }
@@ -376,8 +423,8 @@ class TestPetscii {
                 listOf<Short>(0x08, 0x05, 0x0c, 0x0c, 0x0f, 0x20, 0x57, 0x4f, 0x52, 0x4c, 0x44, 0x20, 0x31, 0x32, 0x33, 0x20, 0x00, 0x21, 0x1c)
         ))
         assertThat(Petscii.encodeScreencode("✓", true), equalTo(listOf<Short>(0x7a)))
-        assertFailsWith<CharConversionException> { Petscii.encodeScreencode("♥", true) }
-        assertFailsWith<CharConversionException> { Petscii.encodeScreencode("π", true) }
+        assertThat("expect fallback", Petscii.encodeScreencode("♥", true), equalTo(listOf<Short>(83)))
+        assertThat("expect fallback", Petscii.encodeScreencode("π", true), equalTo(listOf<Short>(94)))
 
         assertThat(Petscii.decodeScreencode(listOf(0x08, 0x57, 0x1c, 0x7a), true), equalTo("hW£✓"))
         assertFailsWith<ArrayIndexOutOfBoundsException> { Petscii.decodeScreencode(listOf(-1), true) }
@@ -390,8 +437,9 @@ class TestPetscii {
                 listOf<Short>(0x17, 0x0f, 0x12, 0x0c, 0x04, 0x20, 0x31, 0x32, 0x33, 0x20, 0x00, 0x21, 0x1c)))
         assertThat(Petscii.encodeScreencode("♥"), equalTo(listOf<Short>(0x53)))
         assertThat(Petscii.encodeScreencode("π"), equalTo(listOf<Short>(0x5e)))
-        assertFailsWith<CharConversionException> { Petscii.encodeScreencode("✓") }
-        assertFailsWith<CharConversionException> { Petscii.encodeScreencode("hello") }
+        assertThat(Petscii.encodeScreencode("HELLO"), equalTo(listOf<Short>(8, 5, 12, 12, 15)))
+        assertThat("expecting fallback", Petscii.encodeScreencode("hello"), equalTo(listOf<Short>(8, 5, 12, 12, 15)))
+        assertThat("expecting fallback", Petscii.encodeScreencode("✓"), equalTo(listOf<Short>(122)))
 
         assertThat(Petscii.decodeScreencode(listOf(0x17, 0x1c, 0x53, 0x5e)), equalTo("W£♥π"))
         assertFailsWith<ArrayIndexOutOfBoundsException> { Petscii.decodeScreencode(listOf(-1)) }
@@ -502,7 +550,7 @@ class TestMemory {
 
     @Test
     private fun createTestProgramForMemoryRefViaVar(address: Int, vartype: VarDeclType): AssignTarget {
-        val decl = VarDecl(vartype, DataType.BYTE, ZeropageWish.DONTCARE, null, "address", null, NumericLiteralValue.optimalInteger(address, Position.DUMMY), false, false, Position.DUMMY)
+        val decl = VarDecl(vartype, DataType.BYTE, ZeropageWish.DONTCARE, null, "address", NumericLiteralValue.optimalInteger(address, Position.DUMMY), false, false, false, Position.DUMMY)
         val memexpr = IdentifierReference(listOf("address"), Position.DUMMY)
         val target = AssignTarget(null, null, DirectMemoryWrite(memexpr, Position.DUMMY), Position.DUMMY)
         val assignment = Assignment(target, NumericLiteralValue.optimalInteger(0, Position.DUMMY), Position.DUMMY)
@@ -522,7 +570,7 @@ class TestMemory {
 
     @Test
     fun testInValidRamC64_variable() {
-        val decl = VarDecl(VarDeclType.VAR, DataType.BYTE, ZeropageWish.DONTCARE, null, "address", null, null, false, false, Position.DUMMY)
+        val decl = VarDecl(VarDeclType.VAR, DataType.BYTE, ZeropageWish.DONTCARE, null, "address", null, false, false, false, Position.DUMMY)
         val target = AssignTarget(IdentifierReference(listOf("address"), Position.DUMMY), null, null, Position.DUMMY)
         val assignment = Assignment(target, NumericLiteralValue.optimalInteger(0, Position.DUMMY), Position.DUMMY)
         val subroutine = Subroutine("test", emptyList(), emptyList(), emptyList(), emptyList(), emptySet(), null, false, false, mutableListOf(decl, assignment), Position.DUMMY)
@@ -535,7 +583,7 @@ class TestMemory {
     @Test
     fun testInValidRamC64_memmap_variable() {
         val address = 0x1000
-        val decl = VarDecl(VarDeclType.MEMORY, DataType.UBYTE, ZeropageWish.DONTCARE, null, "address", null, NumericLiteralValue.optimalInteger(address, Position.DUMMY), false, false, Position.DUMMY)
+        val decl = VarDecl(VarDeclType.MEMORY, DataType.UBYTE, ZeropageWish.DONTCARE, null, "address", NumericLiteralValue.optimalInteger(address, Position.DUMMY), false, false, false, Position.DUMMY)
         val target = AssignTarget(IdentifierReference(listOf("address"), Position.DUMMY), null, null, Position.DUMMY)
         val assignment = Assignment(target, NumericLiteralValue.optimalInteger(0, Position.DUMMY), Position.DUMMY)
         val subroutine = Subroutine("test", emptyList(), emptyList(), emptyList(), emptyList(), emptySet(), null, false, false, mutableListOf(decl, assignment), Position.DUMMY)
@@ -548,7 +596,7 @@ class TestMemory {
     @Test
     fun testNotInValidRamC64_memmap_variable() {
         val address = 0xd020
-        val decl = VarDecl(VarDeclType.MEMORY, DataType.UBYTE, ZeropageWish.DONTCARE, null, "address", null, NumericLiteralValue.optimalInteger(address, Position.DUMMY), false, false, Position.DUMMY)
+        val decl = VarDecl(VarDeclType.MEMORY, DataType.UBYTE, ZeropageWish.DONTCARE, null, "address", NumericLiteralValue.optimalInteger(address, Position.DUMMY), false, false, false, Position.DUMMY)
         val target = AssignTarget(IdentifierReference(listOf("address"), Position.DUMMY), null, null, Position.DUMMY)
         val assignment = Assignment(target, NumericLiteralValue.optimalInteger(0, Position.DUMMY), Position.DUMMY)
         val subroutine = Subroutine("test", emptyList(), emptyList(), emptyList(), emptyList(), emptySet(), null, false, false, mutableListOf(decl, assignment), Position.DUMMY)
@@ -560,7 +608,7 @@ class TestMemory {
 
     @Test
     fun testInValidRamC64_array() {
-        val decl = VarDecl(VarDeclType.VAR, DataType.ARRAY_UB, ZeropageWish.DONTCARE, null, "address", null, null, false, false, Position.DUMMY)
+        val decl = VarDecl(VarDeclType.VAR, DataType.ARRAY_UB, ZeropageWish.DONTCARE, null, "address", null, false, false, false, Position.DUMMY)
         val arrayindexed = ArrayIndexedExpression(IdentifierReference(listOf("address"), Position.DUMMY), ArrayIndex(NumericLiteralValue.optimalInteger(1, Position.DUMMY), Position.DUMMY), Position.DUMMY)
         val target = AssignTarget(null, arrayindexed, null, Position.DUMMY)
         val assignment = Assignment(target, NumericLiteralValue.optimalInteger(0, Position.DUMMY), Position.DUMMY)
@@ -574,7 +622,7 @@ class TestMemory {
     @Test
     fun testInValidRamC64_array_memmapped() {
         val address = 0x1000
-        val decl = VarDecl(VarDeclType.MEMORY, DataType.ARRAY_UB, ZeropageWish.DONTCARE, null, "address", null, NumericLiteralValue.optimalInteger(address, Position.DUMMY), false, false, Position.DUMMY)
+        val decl = VarDecl(VarDeclType.MEMORY, DataType.ARRAY_UB, ZeropageWish.DONTCARE, null, "address", NumericLiteralValue.optimalInteger(address, Position.DUMMY), false, false, false, Position.DUMMY)
         val arrayindexed = ArrayIndexedExpression(IdentifierReference(listOf("address"), Position.DUMMY), ArrayIndex(NumericLiteralValue.optimalInteger(1, Position.DUMMY), Position.DUMMY), Position.DUMMY)
         val target = AssignTarget(null, arrayindexed, null, Position.DUMMY)
         val assignment = Assignment(target, NumericLiteralValue.optimalInteger(0, Position.DUMMY), Position.DUMMY)
@@ -588,7 +636,7 @@ class TestMemory {
     @Test
     fun testNotValidRamC64_array_memmapped() {
         val address = 0xe000
-        val decl = VarDecl(VarDeclType.MEMORY, DataType.ARRAY_UB, ZeropageWish.DONTCARE, null, "address", null, NumericLiteralValue.optimalInteger(address, Position.DUMMY), false, false, Position.DUMMY)
+        val decl = VarDecl(VarDeclType.MEMORY, DataType.ARRAY_UB, ZeropageWish.DONTCARE, null, "address", NumericLiteralValue.optimalInteger(address, Position.DUMMY), false, false, false, Position.DUMMY)
         val arrayindexed = ArrayIndexedExpression(IdentifierReference(listOf("address"), Position.DUMMY), ArrayIndex(NumericLiteralValue.optimalInteger(1, Position.DUMMY), Position.DUMMY), Position.DUMMY)
         val target = AssignTarget(null, arrayindexed, null, Position.DUMMY)
         val assignment = Assignment(target, NumericLiteralValue.optimalInteger(0, Position.DUMMY), Position.DUMMY)

compiler/test/arithmetic/Makefile

@@ -0,0 +1,13 @@
+.PHONY: all clean test
+
+all: test
+
+clean:
+	rm -f *.prg *.asm *.vice-*
+
+test: clean
+	p8compile -target cx16 *.p8 >/dev/null
+	for program in *.prg; do \
+		echo "RUNNING:" $$program ; \
+		x16emu -run -prg $$program >/dev/null ; \
+	done

compiler/test/comparisons/Makefile

@@ -0,0 +1,18 @@
+.PHONY: all clean test
+
+all: test
+
+clean:
+	rm -f *.prg *.asm *.vice-* test_*.p8
+
+test: clean generate test_prgs
+
+generate:
+	python make_tests.py
+	p8compile -noopt -target cx16 *.p8 >/dev/null
+
+test_prgs:
+	for program in *.prg; do \
+		echo "RUNNING:" $$program ; \
+		x16emu -run -prg $$program >/dev/null ; \
+	done

compiler/test/comparisons/make_tests.py

@@ -0,0 +1,508 @@
+# generates various Prog8 files with a huge amount of number comparion tests,
+# for all supported datatypes and all comparison operators.
+
+import sys
+
+index = 0
+
+
+def minmaxvalues(dt):
+    if dt == "ubyte":
+        return 0, 255
+    elif dt == "uword":
+        return 0, 65535
+    elif dt == "byte":
+        return -128, 127
+    elif dt == "word":
+        return -32768, 32767
+    elif dt == "float":
+        return -99999999, 99999999
+    else:
+        raise ValueError(dt)
+
+
+def gen_test(dt, comparison, left, right, expected):
+    global index
+    etxt = f"{left} {comparison} {right}"
+    if eval(etxt) != expected:
+        raise ValueError("invalid comparison: "+etxt+" for "+dt)
+    if expected:
+        stmt_ok = lambda ix: "num_successes++"
+        stmt_else = lambda ix: f"error({ix})"
+    else:
+        stmt_ok = lambda ix: f"error({ix})"
+        stmt_else = lambda ix: "num_successes++"
+
+    def c(number):
+        if dt not in ("byte", "ubyte"):
+            return f"({number} as {dt})"
+        return str(number)
+
+    print(
+f"""        left = {c(left)}
+        right = {c(right)}
+"""
+    )
+
+    # const <op> const
+    index += 1
+    print(
+f"""        ; test #{index}
+        if {c(left)} {comparison} {c(right)} {{
+            {stmt_ok(index)}
+        }} else {{
+            {stmt_else(index)}
+        }}
+""")
+    # const <op> var
+    index += 1
+    print(
+f"""        ; test #{index}
+        if {c(left)} {comparison} right {{
+            {stmt_ok(index)}
+        }} else {{
+            {stmt_else(index)}
+        }}
+""")
+    # const <op> expr
+    index += 1
+    print(
+f"""        ; test #{index}
+        if {c(left)} {comparison} right+zero {{
+            {stmt_ok(index)}
+        }} else {{
+            {stmt_else(index)}
+        }}
+""")
+    # var <op> const
+    index += 1
+    print(
+f"""        ; test #{index}
+        if left {comparison} {c(right)} {{
+            {stmt_ok(index)}
+        }} else {{
+            {stmt_else(index)}
+        }}
+""")
+    # var <op> var
+    index += 1
+    print(
+f"""        ; test #{index}
+        if left {comparison} right {{
+            {stmt_ok(index)}
+        }} else {{
+            {stmt_else(index)}
+        }}
+""")
+    # var <op> expr
+    index += 1
+    print(
+f"""        ; test #{index}
+        if left {comparison} right+zero {{
+            {stmt_ok(index)}
+        }} else {{
+            {stmt_else(index)}
+        }}
+""")
+    # expr <op> const
+    index += 1
+    print(
+f"""        ; test #{index}
+        if left+zero {comparison} {c(right)} {{
+            {stmt_ok(index)}
+        }} else {{
+            {stmt_else(index)}
+        }}
+""")
+    # expr <op> var
+    index += 1
+    print(
+f"""        ; test #{index}
+        if left+zero {comparison} right {{
+            {stmt_ok(index)}
+        }} else {{
+            {stmt_else(index)}
+        }}
+""")
+    # expr <op> expr
+    index += 1
+    print(
+f"""        ; test #{index}
+        if left+zero {comparison} right+zero {{
+            {stmt_ok(index)}
+        }} else {{
+            {stmt_else(index)}
+        }}
+""")
+
+
+def gen_comp_header(dt, operator):
+    print("        ; tests: ", dt, operator)
+    print("        comparison = \""+operator+"\"")
+    print("        txt.print(datatype)")
+    print("        txt.spc()")
+    print("        txt.print(comparison)")
+    print("        txt.nl()")
+
+
+def gen_comp_equal(dt):
+    minval, maxval = minmaxvalues(dt)
+    gen_comp_header(dt, "==")
+    gen_test(dt, "==", 0, 0, True)
+    gen_test(dt, "==", 0, 1, False)
+    gen_test(dt, "==", 100, 100, True)
+    gen_test(dt, "==", 100, 101, False)
+    if maxval >= 200:
+        gen_test(dt, "==", 200, 200, True)
+        gen_test(dt, "==", 200, 201, False)
+    if maxval >= 9999:
+        gen_test(dt, "==", 9999, 9999, True)
+        gen_test(dt, "==", 9999, 10000, False)
+        gen_test(dt, "==", 0x5000, 0x5000, True)
+        gen_test(dt, "==", 0x5000, 0x5001, False)
+        gen_test(dt, "==", 0x5000, 0x4fff, False)
+    if maxval >= 30000:
+        gen_test(dt, "==", 30000, 30000, True)
+        gen_test(dt, "==", 30000, 30001, False)
+    if maxval >= 40000:
+        gen_test(dt, "==", 0xf000, 0xf000, True)
+        gen_test(dt, "==", 0xf000, 0xf001, False)
+        gen_test(dt, "==", 0xf000, 0xffff, False)
+    if minval < 0:
+        gen_test(dt, "==", 0, -1, False)
+        gen_test(dt, "==", -100, -100, True)
+    if minval < -200:
+        gen_test(dt, "==", -200, -200, True)
+        gen_test(dt, "==", -200, -201, False)
+    if minval < -9999:
+        gen_test(dt, "==", -0x5000, -0x5000, True)
+        gen_test(dt, "==", -0x5000, -0x5001, False)
+        gen_test(dt, "==", -0x5000, -0x4fff, False)
+        gen_test(dt, "==", -9999, -9999, True)
+        gen_test(dt, "==", -9999, -10000, False)
+    gen_test(dt, "==", minval, minval, True)
+    gen_test(dt, "==", minval, minval+1, False)
+    gen_test(dt, "==", maxval, maxval, True)
+    gen_test(dt, "==", maxval, maxval-1, False)
+
+
+def gen_comp_notequal(dt):
+    minval, maxval = minmaxvalues(dt)
+    gen_comp_header(dt, "!=")
+    gen_test(dt, "!=", 0, 0, False)
+    gen_test(dt, "!=", 0, 1, True)
+    gen_test(dt, "!=", 100, 100, False)
+    gen_test(dt, "!=", 100, 101, True)
+    if maxval >= 200:
+        gen_test(dt, "!=", 200, 200, False)
+        gen_test(dt, "!=", 200, 201, True)
+    if maxval >= 9999:
+        gen_test(dt, "!=", 9999, 9999, False)
+        gen_test(dt, "!=", 9999, 10000, True)
+        gen_test(dt, "!=", 0x5000, 0x5000, False)
+        gen_test(dt, "!=", 0x5000, 0x5001, True)
+        gen_test(dt, "!=", 0x5000, 0x4fff, True)
+    if maxval >= 30000:
+        gen_test(dt, "!=", 30000, 30000, False)
+        gen_test(dt, "!=", 30000, 30001, True)
+    if maxval >= 40000:
+        gen_test(dt, "!=", 0xf000, 0xf000, False)
+        gen_test(dt, "!=", 0xf000, 0xf001, True)
+        gen_test(dt, "!=", 0xf000, 0xffff, True)
+    if minval < 0:
+        gen_test(dt, "!=", 0, -1, True)
+        gen_test(dt, "!=", -100, -100, False)
+    if minval < -200:
+        gen_test(dt, "!=", -200, -200, False)
+        gen_test(dt, "!=", -200, -201, True)
+    if minval < -9999:
+        gen_test(dt, "!=", -0x5000, -0x5000, False)
+        gen_test(dt, "!=", -0x5000, -0x5001, True)
+        gen_test(dt, "!=", -0x5000, -0x4fff, True)
+        gen_test(dt, "!=", -9999, -9999, False)
+        gen_test(dt, "!=", -9999, -10000, True)
+    gen_test(dt, "!=", minval, minval, False)
+    gen_test(dt, "!=", minval, minval+1, True)
+    gen_test(dt, "!=", maxval, maxval, False)
+    gen_test(dt, "!=", maxval, maxval-1, True)
+
+
+def gen_comp_less(dt):
+    minval, maxval = minmaxvalues(dt)
+    gen_comp_header(dt, "<")
+    gen_test(dt, "<", 0, 0, False)
+    gen_test(dt, "<", 0, 1, True)
+    gen_test(dt, "<", 100, 100, False)
+    gen_test(dt, "<", 100, 101, True)
+    gen_test(dt, "<", 100, 99, False)
+    if maxval >= 200:
+        gen_test(dt, "<", 200, 200, False)
+        gen_test(dt, "<", 200, 201, True)
+        gen_test(dt, "<", 200, 199, False)
+    if maxval >= 9999:
+        gen_test(dt, "<", 9999, 9999, False)
+        gen_test(dt, "<", 9999, 10000, True)
+        gen_test(dt, "<", 9999, 9998, False)
+        gen_test(dt, "<", 0x5000, 0x5000, False)
+        gen_test(dt, "<", 0x5000, 0x5001, True)
+        gen_test(dt, "<", 0x5000, 0x4fff, False)
+    if maxval >= 30000:
+        gen_test(dt, "<", 30000, 30000, False)
+        gen_test(dt, "<", 30000, 30001, True)
+        gen_test(dt, "<", 30000, 29999, False)
+    if maxval >= 40000:
+        gen_test(dt, "<", 0xf000, 0xf000, False)
+        gen_test(dt, "<", 0xf000, 0xf001, True)
+        gen_test(dt, "<", 0xf000, 0xefff, False)
+    if minval < 0:
+        gen_test(dt, "<", 0, -1, False)
+        gen_test(dt, "<", -100, -100, False)
+        gen_test(dt, "<", -100, -101, False)
+        gen_test(dt, "<", -100, -99, True)
+    if minval < -200:
+        gen_test(dt, "<", -200, -200, False)
+        gen_test(dt, "<", -200, -201, False)
+        gen_test(dt, "<", -200, -199, True)
+    if minval < -9999:
+        gen_test(dt, "<", -0x5000, -0x5000, False)
+        gen_test(dt, "<", -0x5000, -0x5001, False)
+        gen_test(dt, "<", -0x5000, -0x4fff, True)
+        gen_test(dt, "<", -9999, -9999, False)
+        gen_test(dt, "<", -9999, -10000, False)
+        gen_test(dt, "<", -9999, -9998, True)
+
+
+def gen_comp_greater(dt):
+    minval, maxval = minmaxvalues(dt)
+    gen_comp_header(dt, ">")
+    gen_test(dt, ">", 0, 0, False)
+    gen_test(dt, ">", 0, 1, False)
+    gen_test(dt, ">", 100, 100, False)
+    gen_test(dt, ">", 100, 101, False)
+    gen_test(dt, ">", 100, 99, True)
+    if maxval >= 200:
+        gen_test(dt, ">", 200, 200, False)
+        gen_test(dt, ">", 200, 201, False)
+        gen_test(dt, ">", 200, 199, True)
+    if maxval >= 9999:
+        gen_test(dt, ">", 9999, 9999, False)
+        gen_test(dt, ">", 9999, 10000, False)
+        gen_test(dt, ">", 9999, 9998, True)
+        gen_test(dt, ">", 0x5000, 0x5000, False)
+        gen_test(dt, ">", 0x5000, 0x5001, False)
+        gen_test(dt, ">", 0x5000, 0x4fff, True)
+    if maxval >= 30000:
+        gen_test(dt, ">", 30000, 30000, False)
+        gen_test(dt, ">", 30000, 30001, False)
+        gen_test(dt, ">", 30000, 29999, True)
+    if maxval >= 40000:
+        gen_test(dt, ">", 0xf000, 0xf000, False)
+        gen_test(dt, ">", 0xf000, 0xf001, False)
+        gen_test(dt, ">", 0xf000, 0xefff, True)
+    if minval < 0:
+        gen_test(dt, ">", 0, -1, True)
+        gen_test(dt, ">", -100, -100, False)
+        gen_test(dt, ">", -100, -101, True)
+        gen_test(dt, ">", -100, -99, False)
+    if minval < -200:
+        gen_test(dt, ">", -200, -200, False)
+        gen_test(dt, ">", -200, -201, True)
+        gen_test(dt, ">", -200, -199, False)
+    if minval < -9999:
+        gen_test(dt, ">", -0x5000, -0x5000, False)
+        gen_test(dt, ">", -0x5000, -0x5001, True)
+        gen_test(dt, ">", -0x5000, -0x4fff, False)
+        gen_test(dt, ">", -9999, -9999, False)
+        gen_test(dt, ">", -9999, -10000, True)
+        gen_test(dt, ">", -9999, -9998, False)
+
+
+def gen_comp_lessequal(dt):
+    minval, maxval = minmaxvalues(dt)
+    gen_comp_header(dt, "<=")
+    gen_test(dt, "<=", 0, 0, True)
+    gen_test(dt, "<=", 0, 1, True)
+    gen_test(dt, "<=", 100, 100, True)
+    gen_test(dt, "<=", 100, 101, True)
+    gen_test(dt, "<=", 100, 99, False)
+    if maxval >= 200:
+        gen_test(dt, "<=", 200, 200, True)
+        gen_test(dt, "<=", 200, 201, True)
+        gen_test(dt, "<=", 200, 199, False)
+    if maxval >= 9999:
+        gen_test(dt, "<=", 9999, 9999, True)
+        gen_test(dt, "<=", 9999, 10000, True)
+        gen_test(dt, "<=", 9999, 9998, False)
+        gen_test(dt, "<=", 0x5000, 0x5000, True)
+        gen_test(dt, "<=", 0x5000, 0x5001, True)
+        gen_test(dt, "<=", 0x5000, 0x4fff, False)
+    if maxval >= 30000:
+        gen_test(dt, "<=", 30000, 30000, True)
+        gen_test(dt, "<=", 30000, 30001, True)
+        gen_test(dt, "<=", 30000, 29999, False)
+    if maxval >= 40000:
+        gen_test(dt, "<=", 0xf000, 0xf000, True)
+        gen_test(dt, "<=", 0xf000, 0xf001, True)
+        gen_test(dt, "<=", 0xf000, 0xefff, False)
+    if minval < 0:
+        gen_test(dt, "<=", 0, -1, False)
+        gen_test(dt, "<=", -100, -100, True)
+        gen_test(dt, "<=", -100, -101, False)
+        gen_test(dt, "<=", -100, -99, True)
+    if minval < -200:
+        gen_test(dt, "<=", -200, -200, True)
+        gen_test(dt, "<=", -200, -201, False)
+        gen_test(dt, "<=", -200, -199, True)
+    if minval < -9999:
+        gen_test(dt, "<=", -0x5000, -0x5000, True)
+        gen_test(dt, "<=", -0x5000, -0x5001, False)
+        gen_test(dt, "<=", -0x5000, -0x4fff, True)
+        gen_test(dt, "<=", -9999, -9999, True)
+        gen_test(dt, "<=", -9999, -10000, False)
+        gen_test(dt, "<=", -9999, -9998, True)
+
+
+def gen_comp_greaterequal(dt):
+    minval, maxval = minmaxvalues(dt)
+    gen_comp_header(dt, ">=")
+    gen_test(dt, ">=", 0, 0, True)
+    gen_test(dt, ">=", 0, 1, False)
+    gen_test(dt, ">=", 100, 100, True)
+    gen_test(dt, ">=", 100, 101, False)
+    gen_test(dt, ">=", 100, 99, True)
+    if maxval >= 200:
+        gen_test(dt, ">=", 200, 200, True)
+        gen_test(dt, ">=", 200, 201, False)
+        gen_test(dt, ">=", 200, 199, True)
+    if maxval >= 9999:
+        gen_test(dt, ">=", 9999, 9999, True)
+        gen_test(dt, ">=", 9999, 10000, False)
+        gen_test(dt, ">=", 9999, 9998, True)
+        gen_test(dt, ">=", 0x5000, 0x5000, True)
+        gen_test(dt, ">=", 0x5000, 0x5001, False)
+        gen_test(dt, ">=", 0x5000, 0x4fff, True)
+    if maxval >= 30000:
+        gen_test(dt, ">=", 30000, 30000, True)
+        gen_test(dt, ">=", 30000, 30001, False)
+        gen_test(dt, ">=", 30000, 29999, True)
+    if maxval >= 40000:
+        gen_test(dt, ">=", 0xf000, 0xf000, True)
+        gen_test(dt, ">=", 0xf000, 0xf001, False)
+        gen_test(dt, ">=", 0xf000, 0xefff, True)
+    if minval < 0:
+        gen_test(dt, ">=", 0, -1, True)
+        gen_test(dt, ">=", -100, -100, True)
+        gen_test(dt, ">=", -100, -101, True)
+        gen_test(dt, ">=", -100, -99, False)
+    if minval < -200:
+        gen_test(dt, ">=", -200, -200, True)
+        gen_test(dt, ">=", -200, -201, True)
+        gen_test(dt, ">=", -200, -199, False)
+    if minval < -9999:
+        gen_test(dt, ">=", -0x5000, -0x5000, True)
+        gen_test(dt, ">=", -0x5000, -0x5001, True)
+        gen_test(dt, ">=", -0x5000, -0x4fff, False)
+        gen_test(dt, ">=", -9999, -9999, True)
+        gen_test(dt, ">=", -9999, -10000, True)
+        gen_test(dt, ">=", -9999, -9998, False)
+
+
+def generate_test_routine_equalsnotequals(dt):
+    print(f"""
+    sub test_comparisons() {{
+        {dt}  left
+        {dt}  right
+        {dt}  zero = 0
+""")
+    gen_comp_equal(dt)
+    gen_comp_notequal(dt)
+    print("    }")
+
+
+def generate_test_routine_lessgreater(dt):
+    print(f"""
+    sub test_comparisons() {{
+        {dt}  left
+        {dt}  right
+        {dt}  zero = 0
+""")
+    gen_comp_less(dt)
+    gen_comp_greater(dt)
+    print("    }")
+
+
+def generate_test_routine_lessequalsgreaterequals(dt):
+    print(f"""
+    sub test_comparisons() {{
+        {dt}  left
+        {dt}  right
+        {dt}  zero = 0
+""")
+    gen_comp_lessequal(dt)
+    gen_comp_greaterequal(dt)
+    print("    }")
+
+
+def generate(dt, operators):
+    global index
+    index = 0
+    print(f"""
+%import textio
+%import floats
+%import test_stack
+%zeropage basicsafe
+
+main {{
+    uword num_errors = 0
+    uword num_successes = 0
+    str datatype = "{dt}"
+    uword comparison
+
+    sub start() {{
+        test_comparisons()
+        print_results()
+        test_stack.test()
+    }}
+
+    sub error(uword index) {{
+        txt.print(" ! error in test ")
+        txt.print_uw(index)
+        txt.chrout(' ')
+        txt.print(datatype)
+        txt.chrout(' ')
+        txt.print(comparison)
+        txt.nl()
+        num_errors++
+    }}
+""")
+
+    if operators=="eq":
+        generate_test_routine_equalsnotequals(dt)
+    elif operators=="lt":
+        generate_test_routine_lessgreater(dt)
+    elif operators=="lteq":
+        generate_test_routine_lessequalsgreaterequals(dt)
+    else:
+        raise ValueError(operators)
+
+    print(f"""
+    sub print_results() {{
+        txt.nl()
+        txt.print("total {index}: ")
+        txt.print_uw(num_successes)
+        txt.print(" good, ")
+        txt.print_uw(num_errors)
+        txt.print(" errors!\\n")
+    }}
+}}
+""")
+
+
+if __name__ == '__main__':
+    for dt in ["ubyte", "uword", "byte", "word", "float"]:
+        sys.stdout = open(f"test_{dt}_eq.p8", "wt")
+        generate(dt, "eq")
+        sys.stdout = open(f"test_{dt}_lt.p8", "wt")
+        generate(dt, "lt")
+        sys.stdout = open(f"test_{dt}_lteq.p8", "wt")
+        generate(dt, "lteq")

compilerAst/build.gradle

@@ -1,7 +1,7 @@
 plugins {
     id 'antlr'
     id 'java'
-    id "org.jetbrains.kotlin.jvm" version "1.4.30"
+    id "org.jetbrains.kotlin.jvm" version "1.5.10"
 }
 
 targetCompatibility = 11

compilerAst/src/prog8/ast/AstToSourceCode.kt

@@ -78,31 +78,18 @@ class AstToSourceCode(val output: (text: String) -> Unit, val program: Program):
     }
 
     private fun datatypeString(dt: DataType): String {
-        return when(dt) {
-            in NumericDatatypes -> dt.toString().toLowerCase()
-            DataType.STR -> dt.toString().toLowerCase()
+        return when (dt) {
+            in NumericDatatypes -> dt.toString().lowercase()
+            DataType.STR -> dt.toString().lowercase()
             DataType.ARRAY_UB -> "ubyte["
             DataType.ARRAY_B -> "byte["
             DataType.ARRAY_UW -> "uword["
             DataType.ARRAY_W -> "word["
             DataType.ARRAY_F -> "float["
-            DataType.STRUCT -> ""       // the name of the struct is enough
             else -> "?????"
         }
     }
 
-    override fun visit(structDecl: StructDecl) {
-        outputln("struct ${structDecl.name} {")
-        scopelevel++
-        for(decl in structDecl.statements) {
-            outputi("")
-            decl.accept(this)
-            output("\n")
-        }
-        scopelevel--
-        outputlni("}")
-    }
-
     override fun visit(decl: VarDecl) {
 
         // if the vardecl is a parameter of a subroutine, don't output it again
@@ -116,13 +103,9 @@ class AstToSourceCode(val output: (text: String) -> Unit, val program: Program):
             VarDeclType.MEMORY -> output("&")
         }
 
-        if(decl.datatype==DataType.STRUCT && decl.struct!=null)
-            output(decl.struct!!.name)
-
         output(datatypeString(decl.datatype))
         if(decl.arraysize!=null) {
-            decl.arraysize!!.indexNum?.accept(this)
-            decl.arraysize!!.indexVar?.accept(this)
+            decl.arraysize!!.indexExpr.accept(this)
         }
         if(decl.isArray)
             output("]")
@@ -138,8 +121,11 @@ class AstToSourceCode(val output: (text: String) -> Unit, val program: Program):
 
     override fun visit(subroutine: Subroutine) {
         output("\n")
+        outputi("")
+        if(subroutine.inline)
+            output("inline ")
         if(subroutine.isAsmSubroutine) {
-            outputi("asmsub ${subroutine.name} (")
+            output("asmsub ${subroutine.name} (")
             for(param in subroutine.parameters.zip(subroutine.asmParameterRegisters)) {
                 val reg =
                         when {
@@ -153,7 +139,7 @@ class AstToSourceCode(val output: (text: String) -> Unit, val program: Program):
             }
         }
         else {
-            outputi("sub ${subroutine.name} (")
+            output("sub ${subroutine.name} (")
             for(param in subroutine.parameters) {
                 output("${datatypeString(param.type)} ${param.name}")
                 if(param!==subroutine.parameters.last())
@@ -249,7 +235,7 @@ class AstToSourceCode(val output: (text: String) -> Unit, val program: Program):
     }
 
     override fun visit(branchStatement: BranchStatement) {
-        output("if_${branchStatement.condition.toString().toLowerCase()} ")
+        output("if_${branchStatement.condition.toString().lowercase()} ")
         branchStatement.truepart.accept(this)
         if(branchStatement.elsepart.statements.isNotEmpty()) {
             output(" else ")
@@ -365,8 +351,7 @@ class AstToSourceCode(val output: (text: String) -> Unit, val program: Program):
     override fun visit(arrayIndexedExpression: ArrayIndexedExpression) {
         arrayIndexedExpression.arrayvar.accept(this)
         output("[")
-        arrayIndexedExpression.indexer.indexNum?.accept(this)
-        arrayIndexedExpression.indexer.indexVar?.accept(this)
+        arrayIndexedExpression.indexer.indexExpr.accept(this)
         output("]")
     }
 

compilerAst/src/prog8/ast/AstToplevel.kt

@@ -8,6 +8,8 @@ import prog8.ast.walk.IAstVisitor
 import java.nio.file.Path
 import kotlin.math.abs
 
+const val internedStringsModuleName = "prog8_interned_strings"
+
 interface IStringEncoding {
     fun encodeString(str: String, altEncoding: Boolean): List<Short>
     fun decodeString(bytes: List<Short>, altEncoding: Boolean): String
@@ -124,18 +126,7 @@ interface INameScope {
 
     fun lookup(scopedName: List<String>, localContext: Node) : Statement? {
         if(scopedName.size>1) {
-            // a scoped name can a) refer to a member of a struct, or b) refer to a name in another module.
-            // try the struct first.
-            val thing = lookup(scopedName.dropLast(1), localContext) as? VarDecl
-            val struct = thing?.struct
-            if (struct != null) {
-                if(struct.statements.any { (it as VarDecl).name == scopedName.last()}) {
-                    // return ref to the mangled name variable
-                    val mangled = mangledStructMemberName(thing.name, scopedName.last())
-                    return thing.definingScope().getLabelOrVariable(mangled)
-                }
-            }
-
+            // a scoped name refers to a name in another module.
             // it's a qualified name, look it up from the root of the module's namespace (consider all modules in the program)
             for(module in localContext.definingModule().program.modules) {
                 var scope: INameScope? = module
@@ -178,7 +169,6 @@ interface INameScope {
         }
     }
 
-    fun containsDefinedVariables() = statements.any { it is VarDecl && (it !is ParameterVarDecl) }
     fun containsCodeOrVars() = statements.any { it !is Directive || it.directive == "%asminclude" || it.directive == "%asm"}
     fun containsNoCodeNorVars() = !containsCodeOrVars()
 
@@ -268,48 +258,64 @@ class Program(val name: String,
         get() = mainModule.loadAddress
 
     var actualLoadAddress: Int = 0
-    private val internedStrings = mutableMapOf<Pair<String, Boolean>, List<String>>()
-    val internedStringsModuleName = "prog8_interned_strings"
+    private val internedStringsUnique = mutableMapOf<Pair<String, Boolean>, List<String>>()
 
     init {
         // insert a container module for all interned strings later
         if(modules.firstOrNull()?.name != internedStringsModuleName) {
-            val internedStringsModule = Module(internedStringsModuleName, mutableListOf(), Position.DUMMY, false, Path.of(""))
+            val internedStringsModule = Module(internedStringsModuleName, mutableListOf(), Position.DUMMY, true, Path.of(""))
             modules.add(0, internedStringsModule)
-            val block = Block(internedStringsModuleName, null, mutableListOf(), false, Position.DUMMY)
+            val block = Block(internedStringsModuleName, null, mutableListOf(), true, Position.DUMMY)
             internedStringsModule.statements.add(block)
             internedStringsModule.linkParents(this)
             internedStringsModule.program = this
         }
     }
 
-    fun entrypoint(): Subroutine? {
+    fun entrypoint(): Subroutine {
         val mainBlocks = allBlocks().filter { it.name=="main" }
         if(mainBlocks.size > 1)
             throw FatalAstException("more than one 'main' block")
-        return if(mainBlocks.isEmpty()) {
-            null
-        } else {
-            mainBlocks[0].subScope("start") as Subroutine?
-        }
+        if(mainBlocks.isEmpty())
+            throw FatalAstException("no 'main' block")
+        return mainBlocks[0].subScope("start") as Subroutine
     }
 
     fun internString(string: StringLiteralValue): List<String> {
+        // Move a string literal into the internal, deduplicated, string pool
+        // replace it with a variable declaration that points to the entry in the pool.
+
+        if(string.parent is VarDecl) {
+            // deduplication can only be performed safely for known-const strings (=string literals OUTSIDE OF A VARDECL)!
+            throw FatalAstException("cannot intern a string literal that's part of a vardecl")
+        }
+
+        fun getScopedName(string: StringLiteralValue): List<String> {
+            val internedStringsBlock = modules
+                .first { it.name == internedStringsModuleName }.statements
+                .first { it is Block && it.name == internedStringsModuleName } as Block
+            val varName = "string_${internedStringsBlock.statements.size}"
+            val decl = VarDecl(
+                VarDeclType.VAR, DataType.STR, ZeropageWish.NOT_IN_ZEROPAGE, null, varName, string,
+                isArray = false, autogeneratedDontRemove = true, sharedWithAsm = false, position = string.position
+            )
+            internedStringsBlock.statements.add(decl)
+            decl.linkParents(internedStringsBlock)
+            return listOf(internedStringsModuleName, decl.name)
+        }
+
         val key = Pair(string.value, string.altEncoding)
-        val existing = internedStrings[key]
-        if(existing!=null)
+        val existing = internedStringsUnique[key]
+        if (existing != null)
             return existing
 
-        val decl = VarDecl(VarDeclType.VAR, DataType.STR, ZeropageWish.NOT_IN_ZEROPAGE, null, "string_${internedStrings.size}", null, string,
-            isArray = false, autogeneratedDontRemove = true, position = string.position)
-        val internedStringsBlock = modules.first { it.name==internedStringsModuleName }.statements.first { it is Block && it.name == internedStringsModuleName}
-        (internedStringsBlock as Block).statements.add(decl)
-        decl.linkParents(internedStringsBlock)
-        val scopedName = listOf(internedStringsModuleName, decl.name)
-        internedStrings[key] = scopedName
+        val scopedName = getScopedName(string)
+        internedStringsUnique[key] = scopedName
         return scopedName
     }
 
+
+
     fun allBlocks(): List<Block> = modules.flatMap { it.statements.filterIsInstance<Block>() }
 
     override val position: Position = Position.DUMMY
@@ -339,8 +345,6 @@ class Module(override val name: String,
 
     override lateinit var parent: Node
     lateinit var program: Program
-    val importedBy = mutableListOf<Module>()
-    val imports = mutableSetOf<Module>()
 
     val loadAddress: Int by lazy {
         val address = (statements.singleOrNull { it is Directive && it.directive == "%address" } as? Directive)?.args?.single()?.int ?: 0
@@ -389,20 +393,6 @@ class GlobalNamespace(val modules: List<Module>, private val builtinFunctionName
             return builtinPlaceholder
         }
 
-        if(scopedName.size>1) {
-            // a scoped name can a) refer to a member of a struct, or b) refer to a name in another module.
-            // try the struct first.
-            val thing = lookup(scopedName.dropLast(1), localContext) as? VarDecl
-            val struct = thing?.struct
-            if (struct != null) {
-                if(struct.statements.any { (it as VarDecl).name == scopedName.last()}) {
-                    // return ref to the mangled name variable
-                    val mangled = mangledStructMemberName(thing.name, scopedName.last())
-                    return thing.definingScope().getLabelOrVariable(mangled)
-                }
-            }
-        }
-
         // special case: the do....until statement can also look INSIDE the anonymous scope
         if(localContext.parent.parent is UntilLoop) {
             val symbolFromInnerScope = (localContext.parent.parent as UntilLoop).body.lookup(scopedName, localContext)
@@ -412,7 +402,7 @@ class GlobalNamespace(val modules: List<Module>, private val builtinFunctionName
 
         // lookup something from the module.
         return when (val stmt = localContext.definingModule().lookup(scopedName, localContext)) {
-            is Label, is VarDecl, is Block, is Subroutine, is StructDecl -> stmt
+            is Label, is VarDecl, is Block, is Subroutine -> stmt
             null -> null
             else -> throw SyntaxError("invalid identifier target type", stmt.position)
         }
@@ -428,10 +418,6 @@ object BuiltinFunctionScopePlaceholder : INameScope {
 }
 
 
-// prefix for struct member variables
-fun mangledStructMemberName(varName: String, memberName: String) = "prog8struct_${varName}_$memberName"
-
-
 fun Number.toHex(): String {
     //  0..15 -> "0".."15"
     //  16..255 -> "$10".."$ff"

compilerAst/src/prog8/ast/antlr/Antr2Kotlin.kt

@@ -45,7 +45,8 @@ private fun prog8Parser.BlockContext.toAst(isInLibrary: Boolean, encoding: IStri
             it.subroutinedeclaration()!=null -> it.subroutinedeclaration().toAst(encoding)
             it.directive()!=null -> it.directive().toAst()
             it.inlineasm()!=null -> it.inlineasm().toAst()
-            else -> throw FatalAstException("weird block statement $it")
+            it.labeldef()!=null -> it.labeldef().toAst()
+            else -> throw FatalAstException("weird block node $it")
         }
     }
     return Block(identifier().text, integerliteral()?.toAst()?.number?.toInt(), blockstatements.toMutableList(), isInLibrary, toPosition())
@@ -61,62 +62,31 @@ private fun prog8Parser.VariabledeclarationContext.toAst(encoding: IStringEncodi
         val vd = it.vardecl()
         return VarDecl(
                 VarDeclType.VAR,
-                vd.datatype()?.toAst() ?: DataType.STRUCT,
+                vd.datatype()?.toAst() ?: DataType.UNDEFINED,
                 if (vd.ZEROPAGE() != null) ZeropageWish.PREFER_ZEROPAGE else ZeropageWish.DONTCARE,
                 vd.arrayindex()?.toAst(encoding),
                 vd.varname.text,
-                null,
                 it.expression().toAst(encoding),
                 vd.ARRAYSIG() != null || vd.arrayindex() != null,
                 false,
+                vd.SHARED()!=null,
                 it.toPosition()
         )
     }
 
-    structvarinitializer()?.let {
-        val vd = it.structvardecl()
-        return VarDecl(
-                VarDeclType.VAR,
-                DataType.STRUCT,
-                ZeropageWish.NOT_IN_ZEROPAGE,
-                null,
-                vd.varname.text,
-                vd.structname.text,
-                it.expression().toAst(encoding),
-                isArray = false,
-                autogeneratedDontRemove = false,
-                position = it.toPosition()
-        )
-    }
-
-    structvardecl()?.let {
-        return VarDecl(
-                VarDeclType.VAR,
-                DataType.STRUCT,
-                ZeropageWish.NOT_IN_ZEROPAGE,
-                null,
-                it.varname.text,
-                it.structname.text,
-                null,
-                isArray = false,
-                autogeneratedDontRemove = false,
-                position = it.toPosition()
-        )
-    }
-
     constdecl()?.let {
         val cvarinit = it.varinitializer()
         val vd = cvarinit.vardecl()
         return VarDecl(
                 VarDeclType.CONST,
-                vd.datatype()?.toAst() ?: DataType.STRUCT,
+                vd.datatype()?.toAst() ?: DataType.UNDEFINED,
                 if (vd.ZEROPAGE() != null) ZeropageWish.PREFER_ZEROPAGE else ZeropageWish.DONTCARE,
                 vd.arrayindex()?.toAst(encoding),
                 vd.varname.text,
-                null,
                 cvarinit.expression().toAst(encoding),
                 vd.ARRAYSIG() != null || vd.arrayindex() != null,
                 false,
+                vd.SHARED() != null,
                 cvarinit.toPosition()
         )
     }
@@ -126,24 +96,18 @@ private fun prog8Parser.VariabledeclarationContext.toAst(encoding: IStringEncodi
         val vd = mvarinit.vardecl()
         return VarDecl(
                 VarDeclType.MEMORY,
-                vd.datatype()?.toAst() ?: DataType.STRUCT,
+                vd.datatype()?.toAst() ?: DataType.UNDEFINED,
                 if (vd.ZEROPAGE() != null) ZeropageWish.PREFER_ZEROPAGE else ZeropageWish.DONTCARE,
                 vd.arrayindex()?.toAst(encoding),
                 vd.varname.text,
-                null,
                 mvarinit.expression().toAst(encoding),
                 vd.ARRAYSIG() != null || vd.arrayindex() != null,
                 false,
+                vd.SHARED()!=null,
                 mvarinit.toPosition()
         )
     }
 
-    structdecl()?.let {
-        return StructDecl(it.identifier().text,
-                it.vardecl().map { vd->vd.toAst(encoding) }.toMutableList(),
-                toPosition())
-    }
-
     throw FatalAstException("weird variable decl $this")
 }
 
@@ -294,7 +258,7 @@ private fun prog8Parser.Asmsub_returnsContext.toAst(): List<AsmSubroutineReturn>
 private fun prog8Parser.Asmsub_paramsContext.toAst(): List<AsmSubroutineParameter>
         = asmsub_param().map {
     val vardecl = it.vardecl()
-    val datatype = vardecl.datatype()?.toAst() ?: DataType.STRUCT
+    val datatype = vardecl.datatype()?.toAst() ?: DataType.UNDEFINED
     val register = it.register().text
     var registerorpair: RegisterOrPair? = null
     var statusregister: Statusflag? = null
@@ -360,7 +324,7 @@ private fun prog8Parser.Sub_return_partContext.toAst(): List<DataType> {
 
 private fun prog8Parser.Sub_paramsContext.toAst(): List<SubroutineParameter> =
         vardecl().map {
-            val datatype = it.datatype()?.toAst() ?: DataType.STRUCT
+            val datatype = it.datatype()?.toAst() ?: DataType.UNDEFINED
             SubroutineParameter(it.varname.text, datatype, it.toPosition())
         }
 
@@ -379,7 +343,7 @@ private fun prog8Parser.ClobberContext.toAst() : Set<CpuRegister> {
     return names.map { CpuRegister.valueOf(it) }.toSet()
 }
 
-private fun prog8Parser.DatatypeContext.toAst() = DataType.valueOf(text.toUpperCase())
+private fun prog8Parser.DatatypeContext.toAst() = DataType.valueOf(text.uppercase())
 
 private fun prog8Parser.ArrayindexContext.toAst(encoding: IStringEncoding) : ArrayIndex =
         ArrayIndex(expression().toAst(encoding), toPosition())
@@ -575,7 +539,9 @@ private fun prog8Parser.Branch_stmtContext.toAst(encoding: IStringEncoding): Bra
     return BranchStatement(branchcondition, trueScope, elseScope, toPosition())
 }
 
-private fun prog8Parser.BranchconditionContext.toAst() = BranchCondition.valueOf(text.substringAfter('_').toUpperCase())
+private fun prog8Parser.BranchconditionContext.toAst() = BranchCondition.valueOf(
+    text.substringAfter('_').uppercase()
+)
 
 private fun prog8Parser.ForloopContext.toAst(encoding: IStringEncoding): ForLoop {
     val loopvar = identifier().toAst()
@@ -633,14 +599,14 @@ private fun prog8Parser.When_choiceContext.toAst(encoding: IStringEncoding): Whe
 private fun prog8Parser.VardeclContext.toAst(encoding: IStringEncoding): VarDecl {
     return VarDecl(
             VarDeclType.VAR,
-            datatype()?.toAst() ?: DataType.STRUCT,
+            datatype()?.toAst() ?: DataType.UNDEFINED,
             if(ZEROPAGE() != null) ZeropageWish.PREFER_ZEROPAGE else ZeropageWish.DONTCARE,
             arrayindex()?.toAst(encoding),
             varname.text,
             null,
-            null,
             ARRAYSIG() != null || arrayindex() != null,
             false,
+            SHARED()!=null,
             toPosition()
     )
 }

compilerAst/src/prog8/ast/antlr/EscapeChars.kt

@@ -10,9 +10,9 @@ fun escape(str: String): String {
             '\n' -> "\\n"
             '\r' -> "\\r"
             '"' -> "\\\""
-            in '\u8000'..'\u80ff' -> "\\x" + (it.toInt() - 0x8000).toString(16).padStart(2, '0')
+            in '\u8000'..'\u80ff' -> "\\x" + (it.code - 0x8000).toString(16).padStart(2, '0')
             in '\u0000'..'\u00ff' -> it.toString()
-            else -> "\\u" + it.toInt().toString(16).padStart(4, '0')
+            else -> "\\u" + it.code.toString(16).padStart(4, '0')
         }
     }
     return es.joinToString("")

compilerAst/src/prog8/ast/base/Base.kt

@@ -17,7 +17,7 @@ enum class DataType {
     ARRAY_UW,           // pass by reference
     ARRAY_W,            // pass by reference
     ARRAY_F,            // pass by reference
-    STRUCT;             // pass by reference
+    UNDEFINED;
 
     /**
      * is the type assignable to the given other type (perhaps via a typecast) without loss of precision?
@@ -60,7 +60,13 @@ enum class DataType {
 enum class CpuRegister {
     A,
     X,
-    Y
+    Y;
+
+    fun asRegisterOrPair(): RegisterOrPair = when(this) {
+        A -> RegisterOrPair.A
+        X -> RegisterOrPair.X
+        Y -> RegisterOrPair.Y
+    }
 }
 
 enum class RegisterOrPair {
@@ -134,8 +140,8 @@ val IterableDatatypes = setOf(
     DataType.ARRAY_F
 )
 val PassByValueDatatypes = NumericDatatypes
-val PassByReferenceDatatypes = IterableDatatypes.plus(DataType.STRUCT)
-val ArrayElementTypes = mapOf(
+val PassByReferenceDatatypes = IterableDatatypes
+val ArrayToElementTypes = mapOf(
         DataType.STR to DataType.UBYTE,
         DataType.ARRAY_B to DataType.BYTE,
         DataType.ARRAY_UB to DataType.UBYTE,
@@ -143,7 +149,7 @@ val ArrayElementTypes = mapOf(
         DataType.ARRAY_UW to DataType.UWORD,
         DataType.ARRAY_F to DataType.FLOAT
 )
-val ElementArrayTypes = mapOf(
+val ElementToArrayTypes = mapOf(
         DataType.BYTE to DataType.ARRAY_B,
         DataType.UBYTE to DataType.ARRAY_UB,
         DataType.WORD to DataType.ARRAY_W,

compilerAst/src/prog8/ast/expressions/AstExpressions.kt

@@ -22,6 +22,7 @@ sealed class Expression: Node {
     abstract fun accept(visitor: AstWalker, parent: Node)
     abstract fun referencesIdentifier(vararg scopedName: String): Boolean
     abstract fun inferType(program: Program): InferredTypes.InferredType
+    abstract val isSimple: Boolean
 
     infix fun isSameAs(assigntarget: AssignTarget) = assigntarget.isSameAs(this)
 
@@ -88,14 +89,14 @@ class PrefixExpression(val operator: String, var expression: Expression, overrid
         return when(operator) {
             "+" -> inferred
             "~", "not" -> {
-                when(inferred.typeOrElse(DataType.STRUCT)) {
+                when(inferred.typeOrElse(DataType.UNDEFINED)) {
                     in ByteDatatypes -> InferredTypes.knownFor(DataType.UBYTE)
                     in WordDatatypes -> InferredTypes.knownFor(DataType.UWORD)
                     else -> inferred
                 }
             }
             "-" -> {
-                when(inferred.typeOrElse(DataType.STRUCT)) {
+                when(inferred.typeOrElse(DataType.UNDEFINED)) {
                     in ByteDatatypes -> InferredTypes.knownFor(DataType.BYTE)
                     in WordDatatypes -> InferredTypes.knownFor(DataType.WORD)
                     else -> inferred
@@ -105,6 +106,8 @@ class PrefixExpression(val operator: String, var expression: Expression, overrid
         }
     }
 
+    override val isSimple = false
+
     override fun toString(): String {
         return "Prefix($operator $expression)"
     }
@@ -133,6 +136,8 @@ class BinaryExpression(var left: Expression, var operator: String, var right: Ex
         return "[$left $operator $right]"
     }
 
+    override val isSimple = false
+
     // binary expression should actually have been optimized away into a single value, before const value was requested...
     override fun constValue(program: Program): NumericLiteralValue? = null
 
@@ -242,6 +247,8 @@ class ArrayIndexedExpression(var arrayvar: IdentifierReference,
         indexer.linkParents(this)
     }
 
+    override val isSimple = indexer.indexExpr is NumericLiteralValue || indexer.indexExpr is IdentifierReference
+
     override fun replaceChildNode(node: Node, replacement: Node) {
         when {
             node===arrayvar -> arrayvar = replacement as IdentifierReference
@@ -261,7 +268,7 @@ class ArrayIndexedExpression(var arrayvar: IdentifierReference,
         if (target is VarDecl) {
             return when (target.datatype) {
                 DataType.STR -> InferredTypes.knownFor(DataType.UBYTE)
-                in ArrayDatatypes -> InferredTypes.knownFor(ArrayElementTypes.getValue(target.datatype))
+                in ArrayDatatypes -> InferredTypes.knownFor(ArrayToElementTypes.getValue(target.datatype))
                 else -> InferredTypes.unknown()
             }
         }
@@ -271,6 +278,8 @@ class ArrayIndexedExpression(var arrayvar: IdentifierReference,
     override fun toString(): String {
         return "ArrayIndexed(ident=$arrayvar, arraysize=$indexer; pos=$position)"
     }
+
+    fun copy() = ArrayIndexedExpression(arrayvar.copy(), indexer.copy(), position)
 }
 
 class TypecastExpression(var expression: Expression, var type: DataType, val implicit: Boolean, override val position: Position) : Expression() {
@@ -281,6 +290,8 @@ class TypecastExpression(var expression: Expression, var type: DataType, val imp
         expression.linkParents(this)
     }
 
+    override val isSimple = false
+
     override fun replaceChildNode(node: Node, replacement: Node) {
         require(replacement is Expression && node===expression)
         expression = replacement
@@ -314,6 +325,8 @@ data class AddressOf(var identifier: IdentifierReference, override val position:
         identifier.parent=this
     }
 
+    override val isSimple = true
+
     override fun replaceChildNode(node: Node, replacement: Node) {
         require(replacement is IdentifierReference && node===identifier)
         identifier = replacement
@@ -335,6 +348,8 @@ class DirectMemoryRead(var addressExpression: Expression, override val position:
         this.addressExpression.linkParents(this)
     }
 
+    override val isSimple = true
+
     override fun replaceChildNode(node: Node, replacement: Node) {
         require(replacement is Expression && node===addressExpression)
         addressExpression = replacement
@@ -351,6 +366,8 @@ class DirectMemoryRead(var addressExpression: Expression, override val position:
     override fun toString(): String {
         return "DirectMemoryRead($addressExpression)"
     }
+
+    fun copy() =  DirectMemoryRead(addressExpression, position)
 }
 
 class NumericLiteralValue(val type: DataType,    // only numerical types allowed
@@ -358,6 +375,8 @@ class NumericLiteralValue(val type: DataType,    // only numerical types allowed
                           override val position: Position) : Expression() {
     override lateinit var parent: Node
 
+    override val isSimple = true
+
     companion object {
         fun fromBoolean(bool: Boolean, position: Position) =
                 NumericLiteralValue(DataType.UBYTE, if (bool) 1 else 0, position)
@@ -489,6 +508,8 @@ class StringLiteralValue(val value: String,
         this.parent = parent
     }
 
+    override val isSimple = true
+
     override fun replaceChildNode(node: Node, replacement: Node) {
         throw FatalAstException("can't replace here")
     }
@@ -519,6 +540,8 @@ class ArrayLiteralValue(val type: InferredTypes.InferredType,     // inferred be
         value.forEach {it.linkParents(this)}
     }
 
+    override val isSimple = true
+
     override fun replaceChildNode(node: Node, replacement: Node) {
         require(replacement is Expression)
         val idx = value.indexOfFirst { it===node }
@@ -542,6 +565,14 @@ class ArrayLiteralValue(val type: InferredTypes.InferredType,     // inferred be
         return type==other.type && value.contentEquals(other.value)
     }
 
+    fun memsize(memsizer: IMemSizer): Int {
+        if(type.isKnown) {
+            val eltType = ArrayToElementTypes.getValue(type.typeOrElse(DataType.UNDEFINED))
+            return memsizer.memorySize(eltType) * value.size
+        }
+        else throw IllegalArgumentException("array datatype is not yet known")
+    }
+
     fun guessDatatype(program: Program): InferredTypes.InferredType {
         // Educated guess of the desired array literal's datatype.
         // If it's inside a for loop, assume the data type of the loop variable is what we want.
@@ -549,17 +580,17 @@ class ArrayLiteralValue(val type: InferredTypes.InferredType,     // inferred be
         if(forloop != null)  {
             val loopvarDt = forloop.loopVarDt(program)
             if(loopvarDt.isKnown) {
-                return if(loopvarDt.typeOrElse(DataType.STRUCT) !in ElementArrayTypes)
+                return if(!loopvarDt.isArrayElement())
                     InferredTypes.InferredType.unknown()
                 else
-                    InferredTypes.InferredType.known(ElementArrayTypes.getValue(loopvarDt.typeOrElse(DataType.STRUCT)))
+                    InferredTypes.InferredType.known(ElementToArrayTypes.getValue(loopvarDt.typeOrElse(DataType.UNDEFINED)))
             }
         }
 
         // otherwise, select the "biggegst" datatype based on the elements in the array.
         val datatypesInArray = value.map { it.inferType(program) }
         require(datatypesInArray.isNotEmpty() && datatypesInArray.all { it.isKnown }) { "can't determine type of empty array" }
-        val dts = datatypesInArray.map { it.typeOrElse(DataType.STRUCT) }
+        val dts = datatypesInArray.map { it.typeOrElse(DataType.UNDEFINED) }
         return when {
             DataType.FLOAT in dts -> InferredTypes.InferredType.known(DataType.ARRAY_F)
             DataType.STR in dts -> InferredTypes.InferredType.known(DataType.ARRAY_UW)
@@ -571,8 +602,7 @@ class ArrayLiteralValue(val type: InferredTypes.InferredType,     // inferred be
                 DataType.ARRAY_W in dts ||
                 DataType.ARRAY_UB in dts ||
                 DataType.ARRAY_B in dts ||
-                DataType.ARRAY_F in dts ||
-                DataType.STRUCT in dts -> InferredTypes.InferredType.known(DataType.ARRAY_UW)
+                DataType.ARRAY_F in dts -> InferredTypes.InferredType.known(DataType.ARRAY_UW)
             else -> InferredTypes.InferredType.unknown()
         }
     }
@@ -581,7 +611,7 @@ class ArrayLiteralValue(val type: InferredTypes.InferredType,     // inferred be
         if(type.istype(targettype))
             return this
         if(targettype in ArrayDatatypes) {
-            val elementType = ArrayElementTypes.getValue(targettype)
+            val elementType = ArrayToElementTypes.getValue(targettype)
             val castArray = value.map{
                 val num = it as? NumericLiteralValue
                 if(num==null) {
@@ -617,6 +647,8 @@ class RangeExpr(var from: Expression,
         step.linkParents(this)
     }
 
+    override val isSimple = true
+
     override fun replaceChildNode(node: Node, replacement: Node) {
         require(replacement is Expression)
         when {
@@ -644,12 +676,12 @@ class RangeExpr(var from: Expression,
             fromDt istype DataType.WORD || toDt istype DataType.WORD -> InferredTypes.knownFor(DataType.ARRAY_W)
             fromDt istype DataType.BYTE || toDt istype DataType.BYTE -> InferredTypes.knownFor(DataType.ARRAY_B)
             else -> {
-                val fdt = fromDt.typeOrElse(DataType.STRUCT)
-                val tdt = toDt.typeOrElse(DataType.STRUCT)
+                val fdt = fromDt.typeOrElse(DataType.UNDEFINED)
+                val tdt = toDt.typeOrElse(DataType.UNDEFINED)
                 if(fdt largerThan tdt)
-                    InferredTypes.knownFor(ElementArrayTypes.getValue(fdt))
+                    InferredTypes.knownFor(ElementToArrayTypes.getValue(fdt))
                 else
-                    InferredTypes.knownFor(ElementArrayTypes.getValue(tdt))
+                    InferredTypes.knownFor(ElementToArrayTypes.getValue(tdt))
             }
         }
     }
@@ -703,20 +735,21 @@ internal fun makeRange(fromVal: Int, toVal: Int, stepVal: Int): IntProgression {
     }
 }
 
-data class IdentifierReference(val nameInSource: List<String>, override val position: Position) : Expression(),
-    IAssignable {
+data class IdentifierReference(val nameInSource: List<String>, override val position: Position) : Expression(), IAssignable {
     override lateinit var parent: Node
 
+    override val isSimple = true
+
     fun targetStatement(program: Program) =
         if(nameInSource.size==1 && nameInSource[0] in program.builtinFunctions.names)
-            BuiltinFunctionStatementPlaceholder(nameInSource[0], position)
+            BuiltinFunctionStatementPlaceholder(nameInSource[0], position, parent)
         else
             program.namespace.lookup(nameInSource, this)
 
     fun targetVarDecl(program: Program): VarDecl? = targetStatement(program) as? VarDecl
     fun targetSubroutine(program: Program): Subroutine? = targetStatement(program) as? Subroutine
 
-    override fun equals(other: Any?) = other is IdentifierReference && other.nameInSource==nameInSource
+    override fun equals(other: Any?) = other is IdentifierReference && other.nameInSource==nameInSource     // NOTE: only compare by the name, not the position!
     override fun hashCode() = nameInSource.hashCode()
 
     override fun linkParents(parent: Node) {
@@ -752,26 +785,17 @@ data class IdentifierReference(val nameInSource: List<String>, override val posi
     override fun inferType(program: Program): InferredTypes.InferredType {
         return when (val targetStmt = targetStatement(program)) {
             is VarDecl -> InferredTypes.knownFor(targetStmt.datatype)
-            is StructDecl -> InferredTypes.knownFor(DataType.STRUCT)
             else -> InferredTypes.InferredType.unknown()
         }
     }
 
-    fun memberOfStruct(program: Program) = this.targetVarDecl(program)?.struct
+    fun wasStringLiteral(program: Program): Boolean {
+        val decl = targetVarDecl(program)
+        if(decl == null || !decl.autogeneratedDontRemove)
+            return false
 
-    fun firstStructVarName(program: Program): String? {
-        // take the name of the first struct member of the structvariable instead
-        // if it's just a regular variable, return null.
-        val struct = memberOfStruct(program) ?: return null
-        val decl = targetVarDecl(program)!!
-        if(decl.datatype!=DataType.STRUCT)
-            return null
-
-        val firstStructMember = struct.nameOfFirstMember()
-        // find the flattened var that belongs to this first struct member
-        val firstVarName = listOf(decl.name, firstStructMember)
-        val firstVar = definingScope().lookup(firstVarName, this) as VarDecl
-        return firstVar.name
+        val scope=decl.definingModule()
+        return scope.name==internedStringsModuleName
     }
 }
 
@@ -786,6 +810,8 @@ class FunctionCall(override var target: IdentifierReference,
         args.forEach { it.linkParents(this) }
     }
 
+    override val isSimple = target.nameInSource.size==1 && (target.nameInSource[0] in setOf("msb", "lsb", "peek", "peekw"))
+
     override fun replaceChildNode(node: Node, replacement: Node) {
         if(node===target)
             target=replacement as IdentifierReference

compilerAst/src/prog8/ast/expressions/InferredTypes.kt

@@ -1,6 +1,6 @@
 package prog8.ast.expressions
 
-import prog8.ast.base.DataType
+import prog8.ast.base.*
 import java.util.*
 
 
@@ -10,7 +10,7 @@ object InferredTypes {
             require(!(datatype!=null && (isUnknown || isVoid))) { "invalid combination of args" }
         }
 
-        val isKnown = datatype!=null
+        val isKnown = datatype!=null && datatype!=DataType.UNDEFINED
         fun typeOrElse(alternative: DataType) = if(isUnknown || isVoid) alternative else datatype!!
         infix fun istype(type: DataType): Boolean = if(isUnknown || isVoid) false else this.datatype==type
 
@@ -42,6 +42,17 @@ object InferredTypes {
                 isKnown && (datatype!! isAssignableTo targetDt)
         infix fun isNotAssignableTo(targetDt: InferredType): Boolean = !this.isAssignableTo(targetDt)
         infix fun isNotAssignableTo(targetDt: DataType): Boolean = !this.isAssignableTo(targetDt)
+
+        fun isBytes() = datatype in ByteDatatypes
+        fun isWords() = datatype in WordDatatypes
+        fun isInteger() = datatype in IntegerDatatypes
+        fun isNumeric() = datatype in NumericDatatypes
+        fun isArray() = datatype in ArrayDatatypes
+        fun isString() = datatype in StringlyDatatypes
+        fun isIterable() = datatype in IterableDatatypes
+        fun isPassByReference() = datatype in PassByReferenceDatatypes
+        fun isPassByValue() = datatype in PassByValueDatatypes
+        fun isArrayElement() = datatype in ElementToArrayTypes
     }
 
     private val unknownInstance = InferredType.unknown()
@@ -57,8 +68,7 @@ object InferredTypes {
             DataType.ARRAY_B to InferredType.known(DataType.ARRAY_B),
             DataType.ARRAY_UW to InferredType.known(DataType.ARRAY_UW),
             DataType.ARRAY_W to InferredType.known(DataType.ARRAY_W),
-            DataType.ARRAY_F to InferredType.known(DataType.ARRAY_F),
-            DataType.STRUCT to InferredType.known(DataType.STRUCT)
+            DataType.ARRAY_F to InferredType.known(DataType.ARRAY_F)
     )
 
     fun void() = voidInstance

compilerAst/src/prog8/ast/statements/AstStatements.kt

@@ -7,6 +7,10 @@ import prog8.ast.walk.AstWalker
 import prog8.ast.walk.IAstVisitor
 
 
+interface ISymbolStatement {
+    val name: String
+}
+
 sealed class Statement : Node {
     abstract fun accept(visitor: IAstVisitor)
     abstract fun accept(visitor: AstWalker, parent: Node)
@@ -31,8 +35,7 @@ sealed class Statement : Node {
 }
 
 
-class BuiltinFunctionStatementPlaceholder(val name: String, override val position: Position) : Statement() {
-    override var parent: Node = ParentSentinel
+class BuiltinFunctionStatementPlaceholder(val name: String, override val position: Position, override var parent: Node) : Statement() {
     override fun linkParents(parent: Node) {}
     override fun accept(visitor: IAstVisitor) = throw FatalAstException("should not iterate over this node")
     override fun accept(visitor: AstWalker, parent: Node) = throw FatalAstException("should not iterate over this node")
@@ -48,7 +51,7 @@ class Block(override val name: String,
             val address: Int?,
             override var statements: MutableList<Statement>,
             val isInLibrary: Boolean,
-            override val position: Position) : Statement(), INameScope {
+            override val position: Position) : Statement(), INameScope, ISymbolStatement {
     override lateinit var parent: Node
 
     override fun linkParents(parent: Node) {
@@ -95,7 +98,7 @@ data class DirectiveArg(val str: String?, val name: String?, val int: Int?, over
     override fun replaceChildNode(node: Node, replacement: Node) = throw FatalAstException("can't replace here")
 }
 
-data class Label(val name: String, override val position: Position) : Statement() {
+data class Label(override val name: String, override val position: Position) : Statement(), ISymbolStatement {
     override lateinit var parent: Node
 
     override fun linkParents(parent: Node) {
@@ -153,22 +156,17 @@ enum class ZeropageWish {
     NOT_IN_ZEROPAGE
 }
 
-
 open class VarDecl(val type: VarDeclType,
                    private val declaredDatatype: DataType,
                    val zeropage: ZeropageWish,
                    var arraysize: ArrayIndex?,
-                   val name: String,
-                   private val structName: String?,
+                   override val name: String,
                    var value: Expression?,
                    val isArray: Boolean,
                    val autogeneratedDontRemove: Boolean,
-                   override val position: Position) : Statement() {
+                   val sharedWithAsm: Boolean,
+                   override val position: Position) : Statement(), ISymbolStatement {
     override lateinit var parent: Node
-    var struct: StructDecl? = null        // set later (because at parse time, we only know the name)
-        private set
-    var structHasBeenFlattened = false      // set later
-        private set
     var allowInitializeWithZero = true
 
     // prefix for literal values that are turned into a variable on the heap
@@ -182,11 +180,11 @@ open class VarDecl(val type: VarDeclType,
                 if(!array.type.isKnown)
                     throw FatalAstException("unknown dt")
                 else
-                    array.type.typeOrElse(DataType.STRUCT)
-            val declaredType = ArrayElementTypes.getValue(arrayDt)
+                    array.type.typeOrElse(DataType.UNDEFINED)
+            val declaredType = ArrayToElementTypes.getValue(arrayDt)
             val arraysize = ArrayIndex.forArray(array)
-            return VarDecl(VarDeclType.VAR, declaredType, ZeropageWish.NOT_IN_ZEROPAGE, arraysize, autoVarName, null, array,
-                    isArray = true, autogeneratedDontRemove = true, position = array.position)
+            return VarDecl(VarDeclType.VAR, declaredType, ZeropageWish.NOT_IN_ZEROPAGE, arraysize, autoVarName, array,
+                    isArray = true, autogeneratedDontRemove = true, sharedWithAsm = false, position = array.position)
         }
 
         fun defaultZero(dt: DataType, position: Position) = when(dt) {
@@ -219,16 +217,10 @@ open class VarDecl(val type: VarDeclType,
         this.parent = parent
         arraysize?.linkParents(this)
         value?.linkParents(this)
-        if(structName!=null) {
-            val structStmt = definingScope().lookup(listOf(structName), this)
-            if(structStmt!=null)
-                struct = definingScope().lookup(listOf(structName), this) as StructDecl
-        }
     }
 
     override fun replaceChildNode(node: Node, replacement: Node) {
-        // TODO the check that node===value is too strict sometimes, but leaving it out allows for bugs to creep through ... :( Perhaps check when adding the replace if there is already a replace on the same node?
-        require(replacement is Expression)
+        require(replacement is Expression && (value==null || node===value))
         value = replacement
         replacement.parent = this
     }
@@ -237,7 +229,7 @@ open class VarDecl(val type: VarDeclType,
     override fun accept(visitor: AstWalker, parent: Node) = visitor.visit(this, parent)
 
     override fun toString(): String {
-        return "VarDecl(name=$name, vartype=$type, datatype=$datatype, struct=$structName, value=$value, pos=$position)"
+        return "VarDecl(name=$name, vartype=$type, datatype=$datatype, value=$value, pos=$position)"
     }
 
     fun zeroElementValue(): NumericLiteralValue {
@@ -247,73 +239,30 @@ open class VarDecl(val type: VarDeclType,
             throw IllegalArgumentException("attempt to get zero value for vardecl that shouldn't get it")
     }
 
-    fun flattenStructMembers(): MutableList<Statement> {
-        val result = struct!!.statements.mapIndexed { index, statement ->
-            val member = statement as VarDecl
-            val initvalue = if(value!=null) (value as ArrayLiteralValue).value[index] else null
-            VarDecl(
-                    VarDeclType.VAR,
-                    member.datatype,
-                    ZeropageWish.NOT_IN_ZEROPAGE,
-                    member.arraysize,
-                    mangledStructMemberName(name, member.name),
-                    struct!!.name,
-                    initvalue,
-                    member.isArray,
-                    true,
-                    member.position
-            )
-        }.toMutableList<Statement>()
-        structHasBeenFlattened = true
-        return result
+    fun copy(): VarDecl {
+        val c = VarDecl(type, declaredDatatype, zeropage, arraysize, name, value, isArray, autogeneratedDontRemove, sharedWithAsm, position)
+        c.allowInitializeWithZero = this.allowInitializeWithZero
+        return c
     }
 }
 
 // a vardecl used only for subroutine parameters
 class ParameterVarDecl(name: String, declaredDatatype: DataType, position: Position)
-    : VarDecl(VarDeclType.VAR, declaredDatatype, ZeropageWish.DONTCARE, null, name, null, null, false, true, position)
+    : VarDecl(VarDeclType.VAR, declaredDatatype, ZeropageWish.DONTCARE, null, name, null, false, true, false, position)
 
-
-class ArrayIndex(var origExpression: Expression?,            // will be replaced later by either the number or the identifier
+class ArrayIndex(var indexExpr: Expression,
                  override val position: Position) : Node {
-    // for code simplicity, either indexed via a constant number or via a variable (no arbitrary expressions)
     override lateinit var parent: Node
-    var indexNum: NumericLiteralValue? = origExpression as? NumericLiteralValue
-    var indexVar: IdentifierReference? = origExpression as? IdentifierReference
-
-    init {
-        if(indexNum!=null || indexVar!=null)
-            origExpression = null
-    }
 
     override fun linkParents(parent: Node) {
         this.parent = parent
-        origExpression?.linkParents(this)
-        indexNum?.linkParents(this)
-        indexVar?.linkParents(this)
+        indexExpr.linkParents(this)
     }
 
     override fun replaceChildNode(node: Node, replacement: Node) {
         require(replacement is Expression)
-        when {
-            node===origExpression -> origExpression = replacement
-            node===indexVar -> {
-                when (replacement) {
-                    is NumericLiteralValue -> {
-                        indexVar = null
-                        indexNum = replacement
-                    }
-                    is IdentifierReference -> {
-                        indexVar = replacement
-                        indexNum = null
-                    }
-                    else -> {
-                        throw FatalAstException("invalid replace")
-                    }
-                }
-            }
-            else -> throw FatalAstException("invalid replace")
-        }
+        if (node===indexExpr) indexExpr = replacement
+        else throw FatalAstException("invalid replace")
     }
 
     companion object {
@@ -323,29 +272,17 @@ class ArrayIndex(var origExpression: Expression?,            // will be replaced
         }
     }
 
-    fun accept(visitor: IAstVisitor) {
-        origExpression?.accept(visitor)
-        indexNum?.accept(visitor)
-        indexVar?.accept(visitor)
-    }
-    fun accept(visitor: AstWalker, parent: Node) {
-        origExpression?.accept(visitor, this)
-        indexNum?.accept(visitor, this)
-        indexVar?.accept(visitor, this)
-    }
+    fun accept(visitor: IAstVisitor) = indexExpr.accept(visitor)
+    fun accept(visitor: AstWalker, parent: Node)  = indexExpr.accept(visitor, this)
 
     override fun toString(): String {
-        return("ArrayIndex($indexNum, $indexVar, pos=$position)")
+        return("ArrayIndex($indexExpr, pos=$position)")
     }
 
-    fun constIndex() = indexNum?.number?.toInt()
+    fun constIndex() = (indexExpr as? NumericLiteralValue)?.number?.toInt()
 
-    infix fun isSameAs(other: ArrayIndex): Boolean {
-        return if(indexNum!=null || indexVar!=null)
-            indexNum==other.indexNum && indexVar == other.indexVar
-        else
-            other.origExpression!=null && origExpression!! isSameAs other.origExpression!!
-    }
+    infix fun isSameAs(other: ArrayIndex): Boolean = indexExpr isSameAs other.indexExpr
+    fun copy() = ArrayIndex(indexExpr, position)
 }
 
 open class Assignment(var target: AssignTarget, var value: Expression, override val position: Position) : Statement() {
@@ -463,9 +400,10 @@ data class AssignTarget(var identifier: IdentifierReference?,
     }
 
     fun toExpression(): Expression {
+        // return a copy of the assignment target but as a source expression.
         return when {
-            identifier != null -> identifier!!
-            arrayindexed != null -> arrayindexed!!
+            identifier != null -> identifier!!.copy()
+            arrayindexed != null -> arrayindexed!!.copy()
             memoryAddress != null -> DirectMemoryRead(memoryAddress.addressExpression, memoryAddress.position)
             else -> throw FatalAstException("invalid assignmenttarget $this")
         }
@@ -510,8 +448,9 @@ data class AssignTarget(var identifier: IdentifierReference?,
         }
         return false
     }
-}
 
+    fun copy() = AssignTarget(identifier?.copy(), arrayindexed?.copy(), memoryAddress?.copy(), position)
+}
 
 class PostIncrDecr(var target: AssignTarget, val operator: String, override val position: Position) : Statement() {
     override lateinit var parent: Node
@@ -599,7 +538,7 @@ class InlineAssembly(val assembly: String, override val position: Position) : St
 
 class AnonymousScope(override var statements: MutableList<Statement>,
                      override val position: Position) : INameScope, Statement() {
-    override val name: String
+    override val name: String = "<anon-$sequenceNumber>"
     override lateinit var parent: Node
 
     companion object {
@@ -607,7 +546,7 @@ class AnonymousScope(override var statements: MutableList<Statement>,
     }
 
     init {
-        name = "<anon-$sequenceNumber>"     // make sure it's an invalid soruce code identifier so user source code can never produce it
+        // make sure it's an invalid soruce code identifier so user source code can never produce it
         sequenceNumber++
     }
 
@@ -639,20 +578,18 @@ class NopStatement(override val position: Position): Statement() {
     override fun accept(visitor: AstWalker, parent: Node) = visitor.visit(this, parent)
 }
 
-
 class AsmGenInfo {
     // This class contains various attributes that influence the assembly code generator.
     // Conceptually it should be part of any INameScope.
     // But because the resulting code only creates "real" scopes on a subroutine level,
     // it's more consistent to only define these attributes on a Subroutine node.
-    var usedAutoArrayIndexerForStatements = mutableListOf<ArrayIndexerInfo>()
     var usedRegsaveA = false
     var usedRegsaveX = false
     var usedRegsaveY = false
     var usedFloatEvalResultVar1 = false
     var usedFloatEvalResultVar2 = false
 
-    class ArrayIndexerInfo(val name: String, val replaces: ArrayIndex)
+    val extraVars = mutableListOf<Triple<DataType, String, Int?>>()
 }
 
 // the subroutine class covers both the normal user-defined subroutines,
@@ -668,7 +605,7 @@ class Subroutine(override val name: String,
                  val isAsmSubroutine: Boolean,
                  val inline: Boolean,
                  override var statements: MutableList<Statement>,
-                 override val position: Position) : Statement(), INameScope {
+                 override val position: Position) : Statement(), INameScope, ISymbolStatement {
 
     constructor(name: String, parameters: List<SubroutineParameter>, returntypes: List<DataType>, statements: MutableList<Statement>, inline: Boolean, position: Position)
             : this(name, parameters, returntypes, emptyList(), determineReturnRegisters(returntypes), emptySet(), null, false, inline, statements, position)
@@ -728,10 +665,9 @@ class Subroutine(override val name: String,
             .asSequence()
             .filter { it is InlineAssembly }
             .map { (it as InlineAssembly).assembly }
-            .count { " rti" in it || "\trti" in it || " rts" in it || "\trts" in it || " jmp" in it || "\tjmp" in it }
+            .count { " rti" in it || "\trti" in it || " rts" in it || "\trts" in it || " jmp" in it || "\tjmp" in it || " bra" in it || "\tbra" in it}
 }
 
-
 open class SubroutineParameter(val name: String,
                                val type: DataType,
                                override val position: Position) : Node {
@@ -978,34 +914,6 @@ class WhenChoice(var values: MutableList<Expression>?,           // if null,  th
     fun accept(visitor: AstWalker, parent: Node) = visitor.visit(this, parent)
 }
 
-
-class StructDecl(override val name: String,
-                 override var statements: MutableList<Statement>,      // actually, only vardecls here
-                 override val position: Position): Statement(), INameScope {
-
-    override lateinit var parent: Node
-
-    override fun linkParents(parent: Node) {
-        this.parent = parent
-        this.statements.forEach { it.linkParents(this) }
-    }
-
-    override fun replaceChildNode(node: Node, replacement: Node) {
-        require(replacement is Statement)
-        val idx = statements.indexOfFirst { it===node }
-        statements[idx] = replacement
-        replacement.parent = this
-    }
-
-    val numberOfElements: Int
-        get() = this.statements.size
-
-    override fun accept(visitor: IAstVisitor) = visitor.visit(this)
-    override fun accept(visitor: AstWalker, parent: Node) = visitor.visit(this, parent)
-
-    fun nameOfFirstMember() = (statements.first() as VarDecl).name
-}
-
 class DirectMemoryWrite(var addressExpression: Expression, override val position: Position) : Node {
     override lateinit var parent: Node
 
@@ -1026,4 +934,5 @@ class DirectMemoryWrite(var addressExpression: Expression, override val position
 
     fun accept(visitor: IAstVisitor) = visitor.visit(this)
     fun accept(visitor: AstWalker, parent: Node) = visitor.visit(this, parent)
+    fun copy() = DirectMemoryWrite(addressExpression, position)
 }

compilerAst/src/prog8/ast/walk/AstWalker.kt

@@ -56,7 +56,7 @@ interface IAstModification {
         }
     }
 
-    class ReplaceNode(private val node: Node, private val replacement: Node, private val parent: Node) :
+    class ReplaceNode(val node: Node, private val replacement: Node, private val parent: Node) :
         IAstModification {
         override fun perform() {
             parent.replaceChildNode(node, replacement)
@@ -76,94 +76,115 @@ interface IAstModification {
 
 
 abstract class AstWalker {
-    open fun before(addressOf: AddressOf, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun before(array: ArrayLiteralValue, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun before(arrayIndexedExpression: ArrayIndexedExpression, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun before(assignTarget: AssignTarget, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun before(assignment: Assignment, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun before(block: Block, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun before(branchStatement: BranchStatement, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun before(breakStmt: Break, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun before(decl: VarDecl, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun before(directive: Directive, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun before(expr: BinaryExpression, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun before(expr: PrefixExpression, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun before(forLoop: ForLoop, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun before(repeatLoop: RepeatLoop, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun before(functionCall: FunctionCall, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun before(functionCallStatement: FunctionCallStatement, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun before(identifier: IdentifierReference, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun before(ifStatement: IfStatement, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun before(inlineAssembly: InlineAssembly, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun before(jump: Jump, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun before(label: Label, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun before(memread: DirectMemoryRead, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun before(memwrite: DirectMemoryWrite, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun before(module: Module, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun before(nopStatement: NopStatement, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun before(numLiteral: NumericLiteralValue, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun before(postIncrDecr: PostIncrDecr, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun before(program: Program, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun before(range: RangeExpr, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun before(untilLoop: UntilLoop, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun before(returnStmt: Return, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun before(scope: AnonymousScope, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun before(string: StringLiteralValue, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun before(structDecl: StructDecl, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun before(subroutine: Subroutine, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun before(typecast: TypecastExpression, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun before(whenChoice: WhenChoice, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun before(whenStatement: WhenStatement, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun before(whileLoop: WhileLoop, parent: Node): Iterable<IAstModification> = emptyList()
+    protected val noModifications = emptyList<IAstModification>()
 
-    open fun after(addressOf: AddressOf, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun after(array: ArrayLiteralValue, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun after(arrayIndexedExpression: ArrayIndexedExpression, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun after(assignTarget: AssignTarget, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun after(assignment: Assignment, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun after(block: Block, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun after(branchStatement: BranchStatement, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun after(breakStmt: Break, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun after(builtinFunctionStatementPlaceholder: BuiltinFunctionStatementPlaceholder, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun after(decl: VarDecl, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun after(directive: Directive, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun after(expr: BinaryExpression, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun after(expr: PrefixExpression, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun after(forLoop: ForLoop, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun after(repeatLoop: RepeatLoop, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun after(functionCall: FunctionCall, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun after(functionCallStatement: FunctionCallStatement, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun after(identifier: IdentifierReference, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun after(ifStatement: IfStatement, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun after(inlineAssembly: InlineAssembly, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun after(jump: Jump, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun after(label: Label, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun after(memread: DirectMemoryRead, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun after(memwrite: DirectMemoryWrite, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun after(module: Module, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun after(nopStatement: NopStatement, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun after(numLiteral: NumericLiteralValue, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun after(postIncrDecr: PostIncrDecr, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun after(program: Program, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun after(range: RangeExpr, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun after(untilLoop: UntilLoop, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun after(returnStmt: Return, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun after(scope: AnonymousScope, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun after(string: StringLiteralValue, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun after(structDecl: StructDecl, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun after(subroutine: Subroutine, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun after(typecast: TypecastExpression, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun after(whenChoice: WhenChoice, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun after(whenStatement: WhenStatement, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun after(whileLoop: WhileLoop, parent: Node): Iterable<IAstModification> = emptyList()
+    open fun before(addressOf: AddressOf, parent: Node): Iterable<IAstModification> = noModifications
+    open fun before(array: ArrayLiteralValue, parent: Node): Iterable<IAstModification> = noModifications
+    open fun before(arrayIndexedExpression: ArrayIndexedExpression, parent: Node): Iterable<IAstModification> = noModifications
+    open fun before(assignTarget: AssignTarget, parent: Node): Iterable<IAstModification> = noModifications
+    open fun before(assignment: Assignment, parent: Node): Iterable<IAstModification> = noModifications
+    open fun before(block: Block, parent: Node): Iterable<IAstModification> = noModifications
+    open fun before(branchStatement: BranchStatement, parent: Node): Iterable<IAstModification> = noModifications
+    open fun before(breakStmt: Break, parent: Node): Iterable<IAstModification> = noModifications
+    open fun before(decl: VarDecl, parent: Node): Iterable<IAstModification> = noModifications
+    open fun before(directive: Directive, parent: Node): Iterable<IAstModification> = noModifications
+    open fun before(expr: BinaryExpression, parent: Node): Iterable<IAstModification> = noModifications
+    open fun before(expr: PrefixExpression, parent: Node): Iterable<IAstModification> = noModifications
+    open fun before(forLoop: ForLoop, parent: Node): Iterable<IAstModification> = noModifications
+    open fun before(repeatLoop: RepeatLoop, parent: Node): Iterable<IAstModification> = noModifications
+    open fun before(functionCall: FunctionCall, parent: Node): Iterable<IAstModification> = noModifications
+    open fun before(functionCallStatement: FunctionCallStatement, parent: Node): Iterable<IAstModification> = noModifications
+    open fun before(identifier: IdentifierReference, parent: Node): Iterable<IAstModification> = noModifications
+    open fun before(ifStatement: IfStatement, parent: Node): Iterable<IAstModification> = noModifications
+    open fun before(inlineAssembly: InlineAssembly, parent: Node): Iterable<IAstModification> = noModifications
+    open fun before(jump: Jump, parent: Node): Iterable<IAstModification> = noModifications
+    open fun before(label: Label, parent: Node): Iterable<IAstModification> = noModifications
+    open fun before(memread: DirectMemoryRead, parent: Node): Iterable<IAstModification> = noModifications
+    open fun before(memwrite: DirectMemoryWrite, parent: Node): Iterable<IAstModification> = noModifications
+    open fun before(module: Module, parent: Node): Iterable<IAstModification> = noModifications
+    open fun before(nopStatement: NopStatement, parent: Node): Iterable<IAstModification> = noModifications
+    open fun before(numLiteral: NumericLiteralValue, parent: Node): Iterable<IAstModification> = noModifications
+    open fun before(postIncrDecr: PostIncrDecr, parent: Node): Iterable<IAstModification> = noModifications
+    open fun before(program: Program, parent: Node): Iterable<IAstModification> = noModifications
+    open fun before(range: RangeExpr, parent: Node): Iterable<IAstModification> = noModifications
+    open fun before(untilLoop: UntilLoop, parent: Node): Iterable<IAstModification> = noModifications
+    open fun before(returnStmt: Return, parent: Node): Iterable<IAstModification> = noModifications
+    open fun before(scope: AnonymousScope, parent: Node): Iterable<IAstModification> = noModifications
+    open fun before(string: StringLiteralValue, parent: Node): Iterable<IAstModification> = noModifications
+    open fun before(subroutine: Subroutine, parent: Node): Iterable<IAstModification> = noModifications
+    open fun before(typecast: TypecastExpression, parent: Node): Iterable<IAstModification> = noModifications
+    open fun before(whenChoice: WhenChoice, parent: Node): Iterable<IAstModification> = noModifications
+    open fun before(whenStatement: WhenStatement, parent: Node): Iterable<IAstModification> = noModifications
+    open fun before(whileLoop: WhileLoop, parent: Node): Iterable<IAstModification> = noModifications
 
-    private val modifications = mutableListOf<Triple<IAstModification, Node, Node>>()
+    open fun after(addressOf: AddressOf, parent: Node): Iterable<IAstModification> = noModifications
+    open fun after(array: ArrayLiteralValue, parent: Node): Iterable<IAstModification> = noModifications
+    open fun after(arrayIndexedExpression: ArrayIndexedExpression, parent: Node): Iterable<IAstModification> = noModifications
+    open fun after(assignTarget: AssignTarget, parent: Node): Iterable<IAstModification> = noModifications
+    open fun after(assignment: Assignment, parent: Node): Iterable<IAstModification> = noModifications
+    open fun after(block: Block, parent: Node): Iterable<IAstModification> = noModifications
+    open fun after(branchStatement: BranchStatement, parent: Node): Iterable<IAstModification> = noModifications
+    open fun after(breakStmt: Break, parent: Node): Iterable<IAstModification> = noModifications
+    open fun after(builtinFunctionStatementPlaceholder: BuiltinFunctionStatementPlaceholder, parent: Node): Iterable<IAstModification> = noModifications
+    open fun after(decl: VarDecl, parent: Node): Iterable<IAstModification> = noModifications
+    open fun after(directive: Directive, parent: Node): Iterable<IAstModification> = noModifications
+    open fun after(expr: BinaryExpression, parent: Node): Iterable<IAstModification> = noModifications
+    open fun after(expr: PrefixExpression, parent: Node): Iterable<IAstModification> = noModifications
+    open fun after(forLoop: ForLoop, parent: Node): Iterable<IAstModification> = noModifications
+    open fun after(repeatLoop: RepeatLoop, parent: Node): Iterable<IAstModification> = noModifications
+    open fun after(functionCall: FunctionCall, parent: Node): Iterable<IAstModification> = noModifications
+    open fun after(functionCallStatement: FunctionCallStatement, parent: Node): Iterable<IAstModification> = noModifications
+    open fun after(identifier: IdentifierReference, parent: Node): Iterable<IAstModification> = noModifications
+    open fun after(ifStatement: IfStatement, parent: Node): Iterable<IAstModification> = noModifications
+    open fun after(inlineAssembly: InlineAssembly, parent: Node): Iterable<IAstModification> = noModifications
+    open fun after(jump: Jump, parent: Node): Iterable<IAstModification> = noModifications
+    open fun after(label: Label, parent: Node): Iterable<IAstModification> = noModifications
+    open fun after(memread: DirectMemoryRead, parent: Node): Iterable<IAstModification> = noModifications
+    open fun after(memwrite: DirectMemoryWrite, parent: Node): Iterable<IAstModification> = noModifications
+    open fun after(module: Module, parent: Node): Iterable<IAstModification> = noModifications
+    open fun after(nopStatement: NopStatement, parent: Node): Iterable<IAstModification> = noModifications
+    open fun after(numLiteral: NumericLiteralValue, parent: Node): Iterable<IAstModification> = noModifications
+    open fun after(postIncrDecr: PostIncrDecr, parent: Node): Iterable<IAstModification> = noModifications
+    open fun after(program: Program, parent: Node): Iterable<IAstModification> = noModifications
+    open fun after(range: RangeExpr, parent: Node): Iterable<IAstModification> = noModifications
+    open fun after(untilLoop: UntilLoop, parent: Node): Iterable<IAstModification> = noModifications
+    open fun after(returnStmt: Return, parent: Node): Iterable<IAstModification> = noModifications
+    open fun after(scope: AnonymousScope, parent: Node): Iterable<IAstModification> = noModifications
+    open fun after(string: StringLiteralValue, parent: Node): Iterable<IAstModification> = noModifications
+    open fun after(subroutine: Subroutine, parent: Node): Iterable<IAstModification> = noModifications
+    open fun after(typecast: TypecastExpression, parent: Node): Iterable<IAstModification> = noModifications
+    open fun after(whenChoice: WhenChoice, parent: Node): Iterable<IAstModification> = noModifications
+    open fun after(whenStatement: WhenStatement, parent: Node): Iterable<IAstModification> = noModifications
+    open fun after(whileLoop: WhileLoop, parent: Node): Iterable<IAstModification> = noModifications
+
+    protected val modifications = mutableListOf<Triple<IAstModification, Node, Node>>()
 
     private fun track(mods: Iterable<IAstModification>, node: Node, parent: Node) {
-        for (it in mods) modifications += Triple(it, node, parent)
+        for (it in mods) {
+//            if(it is IAstModification.ReplaceNode) {
+//                val replaceKey = Pair(it.node, it.node.position)
+//                if(replaceKey in modificationsReplacedNodes)
+//                    throw FatalAstException("there already is a node replacement for $replaceKey - optimizer can't deal with multiple replacements for same node yet. Split the ast modification?")
+//                else
+//                    modificationsReplacedNodes.add(replaceKey)
+//            }
+            modifications += Triple(it, node, parent)
+        }
     }
 
     fun applyModifications(): Int {
+        // check if there are double removes, keep only the last one
+        val removals = modifications.filter { it.first is IAstModification.Remove }
+        if(removals.isNotEmpty()) {
+            val doubles = removals.groupBy { (it.first as IAstModification.Remove).node }.filter { it.value.size>1 }
+            doubles.forEach {
+                for(doubleRemove in it.value.dropLast(1)) {
+                    if(!modifications.removeIf { mod-> mod.first === doubleRemove.first })
+                        throw FatalAstException("ast remove problem")
+                }
+            }
+        }
+
         modifications.forEach {
             it.first.perform()
         }
@@ -212,7 +233,6 @@ abstract class AstWalker {
         track(before(decl, parent), decl, parent)
         decl.value?.accept(this, decl)
         decl.arraysize?.accept(this, decl)
-        decl.struct?.accept(this, decl)
         track(after(decl, parent), decl, parent)
     }
 
@@ -412,11 +432,5 @@ abstract class AstWalker {
         whenChoice.statements.accept(this, whenChoice)
         track(after(whenChoice, parent), whenChoice, parent)
     }
-
-    fun visit(structDecl: StructDecl, parent: Node) {
-        track(before(structDecl, parent), structDecl, parent)
-        structDecl.statements.forEach { it.accept(this, structDecl) }
-        track(after(structDecl, parent), structDecl, parent)
-    }
 }
 

compilerAst/src/prog8/ast/walk/IAstVisitor.kt

@@ -33,7 +33,6 @@ interface IAstVisitor {
     fun visit(decl: VarDecl) {
         decl.value?.accept(this)
         decl.arraysize?.accept(this)
-        decl.struct?.accept(this)
     }
 
     fun visit(subroutine: Subroutine) {
@@ -170,8 +169,4 @@ interface IAstVisitor {
         whenChoice.values?.forEach { it.accept(this) }
         whenChoice.statements.accept(this)
     }
-
-    fun visit(structDecl: StructDecl) {
-        structDecl.statements.forEach { it.accept(this) }
-    }
 }

compilerAst/src/prog8/parser/ModuleParsing.kt

@@ -25,9 +25,12 @@ fun moduleName(fileName: Path) = fileName.toString().substringBeforeLast('.')
 internal fun pathFrom(stringPath: String, vararg rest: String): Path  = FileSystems.getDefault().getPath(stringPath, *rest)
 
 
-class ModuleImporter {
+class ModuleImporter(private val program: Program,
+                     private val encoder: IStringEncoding,
+                     private val compilationTargetName: String,
+                     private val libdirs: List<String>) {
 
-    fun importModule(program: Program, filePath: Path, encoder: IStringEncoding, compilationTargetName: String): Module {
+    fun importModule(filePath: Path): Module {
         print("importing '${moduleName(filePath.fileName)}'")
         if(filePath.parent!=null) {
             var importloc = filePath.toString()
@@ -41,16 +44,18 @@ class ModuleImporter {
         if(!Files.isReadable(filePath))
             throw ParsingFailedError("No such file: $filePath")
 
-        val input = CharStreams.fromPath(filePath)
-        return importModule(program, input, filePath, false, encoder, compilationTargetName)
+        var content = filePath.toFile().readText().replace("\r\n", "\n")    // normalize line endings
+        if(content.last()!='\n')
+            content+='\n'   // grammar requires blocks (and thus module files) to end in an EOL
+
+        return importModule(CharStreams.fromString(content), filePath, false)
     }
 
-    fun importLibraryModule(program: Program, name: String,
-                                     encoder: IStringEncoding, compilationTargetName: String): Module? {
+    fun importLibraryModule(name: String): Module? {
         val import = Directive("%import", listOf(
                 DirectiveArg("", name, 42, position = Position("<<<implicit-import>>>", 0, 0, 0))
         ), Position("<<<implicit-import>>>", 0, 0, 0))
-        return executeImportDirective(program, import, Paths.get(""), encoder, compilationTargetName)
+        return executeImportDirective(import, Paths.get(""))
     }
 
     private class MyErrorListener: ConsoleErrorListener() {
@@ -62,11 +67,12 @@ class ModuleImporter {
                 is prog8Parser -> System.err.println("${recognizer.inputStream.sourceName}:$line:$charPositionInLine: $msg")
                 else -> System.err.println("$line:$charPositionInLine $msg")
             }
+            if(numberOfErrors>=5)
+                throw ParsingFailedError("There are too many parse errors. Stopping.")
         }
     }
 
-    private fun importModule(program: Program, stream: CharStream, modulePath: Path, isLibrary: Boolean,
-                             encoder: IStringEncoding, compilationTargetName: String): Module {
+    private fun importModule(stream: CharStream, modulePath: Path, isLibrary: Boolean): Module {
         val moduleName = moduleName(modulePath.fileName)
         val lexer = CustomLexer(modulePath, stream)
         lexer.removeErrorListeners()
@@ -95,14 +101,13 @@ class ModuleImporter {
         lines.asSequence()
                 .mapIndexed { i, it -> i to it }
                 .filter { (it.second as? Directive)?.directive == "%import" }
-                .forEach { executeImportDirective(program, it.second as Directive, modulePath, encoder, compilationTargetName) }
+                .forEach { executeImportDirective(it.second as Directive, modulePath) }
 
         moduleAst.statements = lines
         return moduleAst
     }
 
-    private fun executeImportDirective(program: Program, import: Directive, source: Path,
-                                       encoder: IStringEncoding, compilationTargetName: String): Module? {
+    private fun executeImportDirective(import: Directive, source: Path): Module? {
         if(import.directive!="%import" || import.args.size!=1 || import.args[0].name==null)
             throw SyntaxError("invalid import directive", import.position)
         val moduleName = import.args[0].name!!
@@ -120,12 +125,12 @@ class ModuleImporter {
                     val (resource, resourcePath) = rsc
                     resource.use {
                         println("importing '$moduleName' (library)")
-                        importModule(program, CharStreams.fromStream(it), Paths.get("@embedded@/$resourcePath"),
-                            true, encoder, compilationTargetName)
+                        val content = it.reader().readText().replace("\r\n", "\n")
+                        importModule(CharStreams.fromString(content), Paths.get("@embedded@/$resourcePath"), true)
                     }
                 } else {
                     val modulePath = tryGetModuleFromFile(moduleName, source, import.position)
-                    importModule(program, modulePath, encoder, compilationTargetName)
+                    importModule(modulePath)
                 }
 
         removeDirectivesFromImportedModule(importedModule)
@@ -157,15 +162,10 @@ class ModuleImporter {
 
     private fun tryGetModuleFromFile(name: String, source: Path, position: Position?): Path {
         val fileName = "$name.p8"
-        val locations = if(source.toString().isEmpty()) mutableListOf<Path>() else mutableListOf(source.parent ?: Path.of("."))
-
-        val propPath = System.getProperty("prog8.libdir")
-        if(propPath!=null)
-            locations.add(pathFrom(propPath))
-        val envPath = System.getenv("PROG8_LIBDIR")
-        if(envPath!=null)
-            locations.add(pathFrom(envPath))
-        locations.add(Paths.get(Paths.get("").toAbsolutePath().toString(), "prog8lib"))
+        val libpaths = libdirs.map {Path.of(it)}
+        val locations =
+            (if(source.toString().isEmpty()) libpaths else libpaths.drop(1) + listOf(source.parent ?: Path.of("."))) +
+                listOf(Paths.get(Paths.get("").toAbsolutePath().toString(), "prog8lib"))
 
         locations.forEach {
             val file = pathFrom(it.toString(), fileName)

dbusCompilerService/build.gradle

@@ -2,7 +2,7 @@
 plugins {
     id 'java'
     id 'application'
-    id "org.jetbrains.kotlin.jvm" version "1.4.30"
+    id "org.jetbrains.kotlin.jvm" version "1.5.10"
     id 'com.github.johnrengelman.shadow' version '6.1.0'
 }
 
@@ -18,7 +18,7 @@ repositories {
 dependencies {
     implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8"
     // implementation "org.jetbrains.kotlin:kotlin-reflect"
-    implementation 'org.jetbrains.kotlinx:kotlinx-cli:0.3.1'
+    implementation 'org.jetbrains.kotlinx:kotlinx-cli:0.3.2'
     implementation "com.github.hypfvieh:dbus-java:3.2.4"
     implementation "org.slf4j:slf4j-simple:1.7.30"
 

docs/source/building.rst

@@ -94,7 +94,7 @@ Start the compiler with the ``-watch`` argument to enable this.
 It will compile your program and then instead of exiting, it waits for any changes in the module source files.
 As soon as a change happens, the program gets compiled again.
 It is possible to use the watch mode with multiple modules as well, but it will
-recompile everything in that list even if only of the files got updated.
+recompile everything in that list even if only one of the files got updated.
 
 Other options
 ^^^^^^^^^^^^^
@@ -117,11 +117,11 @@ They are embedded into the packaged release version of the compiler so you don't
 where they are, but their names are still reserved.
 
 
-User defined library files
-^^^^^^^^^^^^^^^^^^^^^^^^^^
+User defined library files and -location
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 You can create library files yourself too that can be shared among programs.
-You can tell the compiler where it should look for these files, by setting the java command line property ``prog8.libdir``
-or by setting the ``PROG8_LIBDIR`` environment variable to the correct directory.
+You can tell the compiler where it should look for these files, by using
+the libdirs command line option.
 
 
 .. _debugging:

docs/source/index.rst

@@ -42,20 +42,25 @@ Language features
 -----------------
 
 - It is a cross-compiler running on modern machines (Linux, MacOS, Windows, ...)
-  The generated output is a machine code program runnable on actual 8-bit 6502 hardware.
-- Provide a very convenient edit/compile/run cycle by being able to directly launch
+  It generates a machine code program runnable on actual 8-bit 6502 hardware.
+- Fast execution speed due to compilation to native assembly code. It's possible to write certain raster interrupt 'demoscene' effects purely in Prog8.
+- Provides a very convenient edit/compile/run cycle by being able to directly launch
   the compiled program in an emulator and provide debugging information to this emulator.
 - Based on simple and familiar imperative structured programming (it looks like a mix of C and Python)
 - Modular programming and scoping via modules, code blocks, and subroutines.
 - Provide high level programming constructs but at the same time stay close to the metal;
   still able to directly use memory addresses and ROM subroutines,
   and inline assembly to have full control when every register, cycle or byte matters
-- Arbitrary number of subroutine parameters, Complex nested expressions are possible
-- No stack frame allocations because parameters and local variables are automatically allocated statically
+- Subroutines with parameters and return values
+- Complex nested expressions are possible
+- Variables are allocated statically
 - Nested subroutines can access variables from outer scopes to avoids the overhead to pass everything via parameters
-- Variable data types include signed and unsigned bytes and words, arrays, strings and floats.
+- Variable data types include signed and unsigned bytes and words, arrays, strings.
+- Floating point math also supported if the target system provides floating point library routines (C64 and Cx16 both do).
+- Strings can contain escaped characters but also many symbols directly if they have a petscii equivalent, such as "♠♥♣♦π▚●○╳". Characters like ^, _, \\, {, } and | are also accepted and converted to the closest petscii equivalents.
 - High-level code optimizations, such as const-folding, expression and statement simplifications/rewriting.
 - Many built-in functions, such as ``sin``, ``cos``, ``rnd``, ``abs``, ``min``, ``max``, ``sqrt``, ``msb``, ``rol``, ``ror``, ``swap``, ``sort`` and ``reverse``
+- Programs can be run multiple times without reloading because of automatic variable (re)initializations.
 - Supports the sixteen 'virtual' 16-bit registers R0 .. R15 from the Commander X16, also on the C64.
 - If you only use standard kernal and prog8 library routines, it is possible to compile the *exact same program* for both machines (just change the compiler target flag)!
 
@@ -145,6 +150,8 @@ For MacOS you can use the Homebrew system to install a recent version of OpenJDK
 Finally: an **emulator** (or a real machine ofcourse) to test and run your programs on.
 In C64 mode, thhe compiler assumes the presence of the `Vice emulator <http://vice-emu.sourceforge.net/>`_.
 If you're targeting the CommanderX16 instead, there's the `x16emu <https://github.com/commanderx16/x16-emulator>`_.
+Make sure you use cx16 emulator and roms **V39 or newer**! Starting from version 6.5, prog8 targets that system version.
+Your program may work on V38 but that will only be by luck.
 
 .. important::
     **Building the compiler itself:** (*Only needed if you have not downloaded a pre-built 'fat-jar'*)
@@ -161,11 +168,11 @@ If you're targeting the CommanderX16 instead, there's the `x16emu <https://githu
     :maxdepth: 2
     :caption: Contents of this manual:
 
-    targetsystem.rst
     building.rst
     programming.rst
     syntaxreference.rst
     libraries.rst
+    targetsystem.rst
     technical.rst
     todo.rst
 

docs/source/libraries.rst

@@ -99,13 +99,32 @@ sys (part of syslib)
     Returns the last address of the program in memory + 1.
     Can be used to load dynamic data after the program, instead of hardcoding something.
 
+``wait(uword jiffies)``
+    wait approximately the given number of jiffies (1/60th seconds)
+    note: the system irq handler has to be active for this to work as it depends on the system jiffy clock
+
+``waitvsync()``
+    busy wait till the next vsync has occurred (approximately), without depending on custom irq handling.
+    can be used to avoid screen flicker/tearing when updating screen contents.
+    note: a more accurate way to wait for vsync is to set up a vsync irq handler instead.
+    note for cx16: the system irq handler has to be active for this to work (this is not required on c64)
+
+``waitrastborder()`` (c64 target only)
+    busy wait till the raster position has reached the bottom screen border (approximately)
+    can be used to avoid screen flicker/tearing when updating screen contents.
+    note: a more accurate way to do this is by using a raster irq handler instead.
+
+``reset_system()``
+    Soft-reset the system back to initial power-on Basic prompt.
+    (called automatically by Prog8 when the main subroutine returns and the program is not using basicsafe zeropage option)
+
 
 conv
 ----
 Routines to convert strings to numbers or vice versa.
 
 - numbers to strings, in various formats (binary, hex, decimal)
-- strings in decimal, hex and binary format into numbers
+- strings in decimal, hex and binary format into numbers (bytes, words)
 
 
 textio (txt.*)

docs/source/programming.rst

@@ -67,8 +67,6 @@ Label
     This is a named position in your code where you can jump to from another place.
     You can jump to it with a jump statement elsewhere. It is also possible to use a
     subroutine call to a label (but without parameters and return value).
-    Labels can only be defined in a block or in another subroutine, so you can't define a label
-    inside a loop statement block for instance.
 
 Scope
 	Also known as 'namespace', this is a named box around the symbols defined in it.
@@ -204,6 +202,16 @@ Example::
     byte  @zp  zeropageCounter = 42
 
 
+*shared tag:*
+If you add the ``@shared`` tag to the variable declaration, the compiler will know that this variable
+is a prog8 variable shared with some assembly code elsewhere. This means that the assembly code can
+refer to the variable even if it's otherwise not used in prog8 code itself.
+(usually, these kinds of 'unused' variables are optimized away by the compiler, resulting in an error
+when assembling the rest of the code). Example::
+
+    byte  @shared  assemblyVariable = 42
+
+
 Integers
 ^^^^^^^^
 
@@ -233,6 +241,10 @@ to worry about this yourself)
 
 The largest 5-byte MFLPT float that can be stored is: **1.7014118345e+38**   (negative: **-1.7014118345e+38**)
 
+.. note::
+    On the Commander X16, to use floating point operations, ROM bank 4 has to be enabled (BASIC).
+    Importing the ``floats`` library will do this for you if needed.
+
 
 Arrays
 ^^^^^^
@@ -316,47 +328,22 @@ read the syntax reference on strings.
     For regular assignments you still need to use an explicit ``&`` (address-of) to take
     the address of the string or array.
 
-.. caution::
-    It's probably best to avoid changing the contents in strings and treat them as static.
-    This includes changing certain letters by index, or by assigning a new value, or by
-    modifying the string via other means for example ``substr`` function and its cousins.
-    This is because the changes persist in memory. If your program exits and is restarted
-    (without reloading it from disk), it will then start working with the modified strings
-    instead of the original ones!
-    The same is true for arrays! So be careful to (re)initialize them if needed.
+.. note:: Strings and their (im)mutability
 
+    *String literals outside of a string variable's initialization value*,
+    are considered to be "constant", i.e. the string isn't going to change
+    during the execution of the program. The compiler takes advantage of this in certain
+    ways. For instance, multiple identical occurrences of a string literal are folded into
+    just one string allocation in memory. Examples of such strings are the string literals
+    passed to a subroutine as arguments.
 
-Structs
-^^^^^^^
-
-A struct is a group of one or more other variables.
-This allows you to reuse the definition and manipulate it as a whole.
-Individual variables in the struct are accessed as you would expect, just
-use a scoped name to refer to them: ``structvariable.membername``.
-
-Structs are a bit limited in Prog8: you can only use numerical variables
-as member of a struct, so strings and arrays and other structs can not be part of a struct.
-Also, it is not possible to use a struct itself inside an array.
-Structs are mainly syntactic sugar for repeated groups of vardecls
-and assignments that belong together. However,
-*they are layed out in sequence in memory as the members are defined*
-which may be usefulif you want to pass pointers around.
-
-To create a variable of a struct type you need to define the struct itself,
-and then create a variable with it::
-
-    struct Color {
-        ubyte red
-        ubyte green
-        ubyte blue
-    }
-
-    Color rgb = [255,122,0]     ; note that struct initializer value is same as an array
-    Color another               ; the init value is optional, like arrays
-
-    another = rgb           ; assign all of the values of rgb to another
-    another.blue = 255      ; set a single member
-
+    *Strings that aren't such string literals are considered to be unique*, even if they
+    are the same as a string defined elsewhere. This includes the strings assigned to
+    a string variable in its declaration! These kind of strings are not deduplicated and
+    are just copied into the program in their own unique part of memory. This means that
+    it is okay to treat those strings as mutable; you can safely change the contents
+    of such a string without destroying other occurrences (as long as you stay within
+    the size of the allocated string!)
 
 
 Special types: const and memory-mapped
@@ -451,6 +438,14 @@ Breaking out of a loop prematurely is possible with the ``break`` statement.
     after the loop without first assigning a new value to it!
     (this is an optimization issue to avoid having to deal with mostly useless post-loop logic to adjust the loop variable's value)
 
+.. warning::
+    For efficiency reasons, it is assumed that the ending value of the for loop is actually >= the starting value
+    (or <= if the step is negative).  This means that for loops in prog8 behave differently than in other
+    languages if this is *not* the case! A for loop from ubyte 10 to ubyte 2, for example, will iterate through
+    all values 10, 11, 12, 13, .... 254, 255, 0  (wrapped), 1, 2. In other languages the entire loop will
+    be skipped in such cases. But prog8 omits the overhead of an extra loop range check and/or branch for every for loop
+    by assuming the normal ranges.
+
 
 Conditional Execution
 ---------------------
@@ -642,7 +637,7 @@ Subroutines can be defined in a Block, but also nested inside another subroutine
 With ``asmsub`` you can define a low-level subroutine that is implemented in inline assembly and takes any parameters
 in registers directly.
 
-Trivial subroutines can be tagged as inline to tell the compiler to copy their code
+Trivial subroutines can be tagged as ``inline`` to tell the compiler to copy their code
 in-place to the locations where the subroutine is called, rather than inserting an actual call and return to the
 subroutine. This may increase code size significantly and can only be used in limited scenarios, so YMMV.
 
@@ -739,9 +734,11 @@ sin16(x)
 
 sqrt16(w)
     16 bit unsigned integer Square root. Result is unsigned byte.
+    To do the reverse, squaring an integer, just write ``x*x``.
 
 sqrt(x)
     Floating point Square root.
+    To do the reverse, squaring a floating point number, just write ``x*x`` or ``x**2``.
 
 tan(x)
     Tangent.
@@ -757,11 +754,12 @@ all(x)
     1 ('true') if all of the values in the array value x are 'true' (not zero), else 0 ('false')
 
 len(x)
-    Number of values in the array value x, or the number of characters in a string (excluding the size or 0-byte).
+    Number of values in the array value x, or the number of characters in a string (excluding the 0-byte).
     Note: this can be different from the number of *bytes* in memory if the datatype isn't a byte. See sizeof().
     Note: lengths of strings and arrays are determined at compile-time! If your program modifies the actual
-    length of the string during execution, the value of len(string) may no longer be correct!
-    (use strlen function if you want to dynamically determine the length)
+    length of the string during execution, the value of len(s) may no longer be correct!
+    (use the ``string.length`` routine if you want to dynamically determine the length by counting to the
+    first 0-byte)
 
 max(x)
     Maximum of the values in the array value x
@@ -788,6 +786,12 @@ sort(array)
 
 Miscellaneous
 ^^^^^^^^^^^^^
+
+cmp(x,y)
+    Compare the integer value x to integer value y. Doesn't return a value or boolean result, only sets the processor's status bits!
+    You can use a conditional jumps (``if_cc`` etcetera) to act on this.
+    Normally you should just use a comparison expression (``x < y``)
+
 lsb(x)
     Get the least significant byte of the word x. Equivalent to the cast "x as ubyte".
 
@@ -854,11 +858,6 @@ sizeof(name)
     For an 10 element array of floats, it is 50 (on the C-64, where a float is 5 bytes).
     Note: usually you will be interested in the number of elements in an array, use len() for that.
 
-offsetof(membername)
-    Number of bytes from the start of a struct variable that this member variable is located.
-    For now, this only works on members of a declared struct variable and not yet on members
-    referenced from the struct type itself.  This might be improved in a future version of the language.
-
 swap(x, y)
     Swap the values of numerical variables (or memory locations) x and y in a fast way.
 
@@ -873,6 +872,29 @@ memory(name, size)
     The return value is just a simple uword address so it cannot be used as an array in your program.
     You can only treat it as a pointer or use it in inline assembly.
 
+callfar(bank, address, argumentaddress)      ; NOTE: specific to cx16 compiler target for now
+    Calls an assembly routine in another ram-bank on the CommanderX16 (using the ``jsrfar`` routine)
+    The banked RAM is located in the address range $A000-$BFFF (8 kilobyte).
+    Notice that bank $00 is used by the Kernal and should not be used by user code.
+    The third argument can be used to designate the memory address
+    of an argument for the routine; it will be loaded into the A register and will
+    receive the result value returned by the routine in the A register. If you leave this at zero,
+    no argument passing will be done.
+    If the routine requires different arguments or return values, ``callfar`` cannot be used
+    and you'll have to set up a call to ``jsrfar`` yourself to process this.
+
+callrom(bank, address, argumentaddress)      ; NOTE: specific to cx16 compiler target for now
+    Calls an assembly routine in another rom-bank on the CommanderX16
+    The banked ROM is located in the address range $C000-$FFFF (16 kilobyte).
+    There are 32 banks (0 to 31).
+    The third argument can be used to designate the memory address
+    of an argument for the routine; it will be loaded into the A register and will
+    receive the result value returned by the routine in the A register. If you leave this at zero,
+    no argument passing will be done.
+    If the routine requires different arguments or return values, ``callrom`` cannot be used
+    and you'll have to set up a call in assembly code yourself that handles the banking and
+    argument/returnvalues.
+
 
 Library routines
 ----------------

docs/source/syntaxreference.rst

@@ -108,7 +108,7 @@ Directives
 
 .. data:: %import <name>
 
-	Level: module, block.
+	Level: module.
 	This reads and compiles the named module source file as part of your current program.
 	Symbols from the imported module become available in your code,
 	without a module or filename prefix.
@@ -129,39 +129,39 @@ Directives
       take care of that yourself. The program will just start running from whatever state the machine is in when the
       program was launched.
     - ``force_output`` (in a block) will force the block to be outputted in the final program.
-      Can be useful to make sure some data is generated that would otherwise be discarded because it's not referenced (such as sprite data).
+      Can be useful to make sure some data is generated that would otherwise be discarded because the compiler thinks it's not referenced (such as sprite data)
     - ``align_word`` (in a block) will make the assembler align the start address of this block on a word boundary in memory (so, an even memory address).
     - ``align_page`` (in a block) will make the assembler align the start address of this block on a page boundary in memory (so, the LSB of the address is 0).
 
 
 .. data:: %asmbinary "<filename>" [, <offset>[, <length>]]
 
-    Level: block.
+    Level: not at module scope.
     This directive can only be used inside a block.
     The assembler will include the file as binary bytes at this point, prog8 will not process this at all.
     The optional offset and length can be used to select a particular piece of the file.
     The file is located relative to the current working directory!
 
-.. data:: %asminclude "<filename>", "scopelabel"
+.. data:: %asminclude "<filename>"
 
-    Level: block.
+    Level: not at module scope.
     This directive can only be used inside a block.
     The assembler will include the file as raw assembly source text at this point,
-    prog8 will not process this at all, with one exception: the labels.
-    The scopelabel argument will be used as a prefix to access the labels from the included source code,
-    otherwise you would risk symbol redefinitions or duplications.
-    If you know what you are doing you can leave it as an empty string to not have a scope prefix.
+    prog8 will not process this at all. Symbols defined in the included assembly can not be referenced
+    from prog8 code. However they can be referenced from other assembly code if properly prefixed.
+    Be careful: you risk symbol redefinitions or duplications if you include a piece of
+    assembly into a prog8 block that already defines symbols itself.
     The compiler first looks for the file relative to the same directory as the module containing this statement is in,
     if the file can't be found there it is searched relative to the current directory.
 
 .. data:: %breakpoint
 
-	Level: block, subroutine.
+    Level: not at module scope.
 	Defines a debugging breakpoint at this location. See :ref:`debugging`
 
 .. data:: %asm {{ ... }}
 
-	Level: block, subroutine.
+    Level: not at module scope.
 	Declares that there is *inline assembly code* in the lines enclosed by the curly braces.
 	This code will be written as-is into the generated output file.
 	The assembler syntax used should be for the 3rd party cross assembler tool that Prog8 uses.
@@ -235,9 +235,11 @@ for them. You can give them an initial value as well. That value can be a simple
 or an expression. If you don't provide an intial value yourself, zero will be used.
 You can add a ``@zp`` zeropage-tag, to tell the compiler to prioritize it
 when selecting variables to be put into zeropage.
+You can add a ``@shared`` shared-tag, to tell the compiler that the variable is shared
+with some assembly code and that it should not be optimized away if not used elsewhere.
 The syntax is::
 
-	<datatype>  [ @zp ]  <variable name>   [ = <initial value> ]
+	<datatype>  [ @shared ] [ @zp ]  <variable name>   [ = <initial value> ]
 
 Various examples::
 
@@ -252,8 +254,8 @@ Various examples::
     byte[5]     values                  ; array of 5 bytes, initially set to zero
     byte[5]     values  = 255           ; initialize with five 255 bytes
 
-    word  @zp   zpword = 9999           ; prioritize this when selecting vars for zeropage storage
-    Color       rgb    = {1,255,0}      ; a struct variable with initial values
+    word  @zp     zpword = 9999         ; prioritize this when selecting vars for zeropage storage
+    word  @shared asmvar                ; variable is used in assembly code but not elsewhere
 
 
 Data types
@@ -387,27 +389,6 @@ Syntax is familiar with brackets:  ``arrayvar[x]`` ::
     string[4]       ; the fifth character (=byte) in the string
 
 
-Struct
-^^^^^^
-
-A *struct* has to be defined to specify what its member variables are.
-There are one or more members::
-
-    struct  <structname> {
-        <vardecl>
-        [ <vardecl> ...]
-    }
-
-You can only use numerical variables as member of a struct, so strings and arrays
-and other structs can not be part of a struct. Vice versa, a struct can not occur in an array.
-
-After defining a struct you can use the name of the struct as a data type to declare variables with.
-
-Struct variables can be assigned a struct literal value (also in their declaration as initial value)::
-
-    Color rgb = [255, 100, 0]          ; note that the value is an array
-
-
 String
 ^^^^^^
 
@@ -425,6 +406,9 @@ There are several escape sequences available to put special characters into your
 - ``\uHHHH`` - a unicode codepoint \u0000 - \uffff (16-bit hexadecimal)
 - ``\xHH`` - 8-bit hex value that will be copied verbatim *without encoding*
 
+- String literals can contain many symbols directly if they have a petscii equivalent, such as "♠♥♣♦π▚●○╳".
+  Characters like ^, _, \\, {, } and | (that have no direct PETSCII counterpart) are still accepted and converted to the closest PETSCII equivalents. (Make sure you save the source file in UTF-8 encoding if you use this.)
+
 
 Operators
 ---------
@@ -550,7 +534,7 @@ and can have nothing following it. The close curly brace must be on its own line
 The parameters is a (possibly empty) comma separated list of "<datatype> <parametername>" pairs specifying the input parameters.
 The return type has to be specified if the subroutine returns a value.
 The ``inline`` keyword makes their code copied in-place to the locations where the subroutine is called,
-rather than having an actual call and return to the subroutine. This is meant for trivial subroutines only
+rather than having an actual call and return to the subroutine. This is meant for very small subroutines only
 as it can increase code size significantly.
 
 
@@ -592,7 +576,7 @@ flag such as Carry (Pc).
     Asmsubs can also be tagged as ``inline asmsub`` to make trivial pieces of assembly inserted
     directly instead of a call to them. Note that it is literal copy-paste of code that is done,
     so make sure the assembly is actually written to behave like such - which probably means you
-    don't want a ``rts`` or ``jmp`` in it!
+    don't want a ``rts`` or ``jmp`` or ``bra`` in it!
 
 
 .. note::

docs/source/technical.rst

@@ -1,6 +1,6 @@
-===============
-Technical stuff
-===============
+=================
+Technical details
+=================
 
 All variables are static in memory
 ----------------------------------
@@ -83,3 +83,37 @@ Some builtin functions have a fully custom implementation.
 The compiler will warn about routines that are called and that return a value, if you're not
 doing something with that returnvalue. This can be on purpuse if you're simply not interested in it.
 Use the ``void`` keyword in front of the subroutine call to get rid of the warning in that case.
+
+
+The 6502 CPU's X-register: off-limits
+-------------------------------------
+
+Prog8 uses the cpu's X-register as a pointer in its internal expression evaluation stack.
+When only writing code in Prog8, this is taken care of behind the scenes for you by the compiler.
+However when you are including or linking with assembly routines or kernal/ROM calls that *do*
+use the X register (either clobbering it internally, or using it as a parameter, or return value register),
+those calls will destroy Prog8's stack pointer and this will result in invalid calculations.
+
+You should avoid using the X register in your assembly code, or take preparations.
+If you make sure that the value of the X register is preserved before calling a routine
+that uses it, and restored when the routine is done, you'll be ok.
+
+Routines that return a value in the X register can be called from Prog8 but the return value is
+inaccessible unless you write a short piece of inline assembly code to deal with it yourself, such as::
+
+    ubyte returnvalue
+
+    %asm {{
+        stx  P8ZP_SCRATCH_REG       ; use 'phx/plx' if using 65c02 cpu
+        ldx  #10
+        jsr  routine_using_x
+        stx  returnvalue
+        ldx  P8ZP_SCRATCH_REG
+    }}
+    ; now use 'returnvalue' variable
+
+Prog8 also provides some help to deal with this:
+
+- you should use a ``clobbers(X)`` specification for asmsub routines that modify the X register; the compiler will preserve it for you automatically when such a routine is called
+- the ``sys.rsave()`` and ``sys.rrestore()`` routines can preserve and restore *all* registers (but this is very slow and overkill if you only need to save X)
+

docs/source/todo.rst

@@ -2,31 +2,32 @@
 TODO
 ====
 
-- optimize assigning array and struct variables (multi-element assings -> memcopy)
-- hoist all variable declarations up to the subroutine scope *before* even the constant folding takes place (to avoid undefined symbol errors when referring to a variable from another nested scope in the subroutine)
-- optimize swap of two memread values with index, using the same pointer expression/variable, like swap(@(ptr+1), @(ptr+2))
-- optimize several inner loops in gfx2
-- try to fix the bresenham line routines in graphics and gfx2 (sometimes they're a pixel 'off')
-- add modes 2 and 3 to gfx2 (lowres 4 color and 16 color)
+- test all examples (including imgviewer, assembler and petaxian) before release of the new version
+
+- simplify cx16.joystick_get2() once this cx16 rom issue is resolved: https://github.com/commanderx16/x16-rom/issues/203
+- c64: make the graphics.BITMAP_ADDRESS configurable (VIC banking)
+- get rid of all other TODO's in the code ;-)
+
+
+Low prio
+^^^^^^^^
+- see if we can remove more ".typeOrElse(DataType.UNDEFINED)"
+- optimize several inner loops in gfx2 even further?
+- add modes 2 and 3 to gfx2 (lowres 4 color and 16 color)?
 - add a flood fill routine to gfx2?
 - add a f_seek() routine for the Cx16 that uses its seek dos api?
-- refactor the asmgen into their own submodule?
-- refactor the compiler optimizers into their own submodule?
-- optimizer: detect variables that are written but never read - mark those as unused too and remove them, such as uword unused = memory("unused222", 20) - also remove the memory slab allocation
-- add a compiler option to not remove unused subroutines. this allows for building library programs
+- refactor the asmgen into own submodule
+- refactor the compiler optimizers into own submodule
+- add a compiler option to not remove unused subroutines. this allows for building library programs. But this won't work with 64tass's .proc ...
 - make it possible to use cpu opcodes such as 'nop' as variable names by prefixing all asm vars with something such as ``v_``
-- option to load the built-in library files from a directory instead of the embedded ones (for easier library development/debugging)
-- c64: make the graphics.BITMAP_ADDRESS configurable (VIC banking)
-- some support for recursive subroutines?
-    - via %option recursive?: allocate all params and local vars on estack, don't allow nested subroutines, can begin by first not allowing any local variables just fixing the parameters
-    - Or via a special recursive call operation that copies the current values of all local vars (including arguments) to the stack, replaces the arguments, jsr subroutine, and after returning copy the stack back to the local variables
-- get rid of all other TODO's in the code ;-)
 
 More optimizations
 ^^^^^^^^^^^^^^^^^^
 
 Add more compiler optimizations to the existing ones.
 
+- find a way to optimize if-statement codegen so that "if var & %10000" doesn't use stack & subroutine call, but also that the simple case "if X {...}" remains fast
+- optimizer: detect variables that are written but never read - mark those as unused too and remove them, such as uword unused = memory("unused222", 20) - also remove the memory slab allocation
 - further optimize assignment codegeneration, such as the following:
 - rewrite expression code generator to not use eval stack but a fixed number of predetermined value 'variables' (1 per nesting level?)
 - binexpr splitting (beware self-referencing expressions and asm code ballooning though)