version 4.2

.travis.yml

@@ -4,8 +4,8 @@ sudo: false
 # dist: xenial
 
 before_install:
-  - chmod +x gradlew
+  - chmod +x ./gradlew
 
 script:
-  - gradle test
+  - ./gradlew test
 

README.md

@@ -2,19 +2,28 @@
 [![Build Status](https://travis-ci.org/irmen/prog8.svg?branch=master)](https://travis-ci.org/irmen/prog8)
 [![Documentation](https://readthedocs.org/projects/prog8/badge/?version=latest)](https://prog8.readthedocs.io/)
 
-Prog8 - Structured Programming Language for 8-bit 6502/6510 microprocessors
-===========================================================================
+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 microprocessor from the late 1970's and 1980's
+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):
+which aims to provide many conveniences over raw assembly code (even when using a macro assembler).
 
-- reduction of source code length
+Documentation
+-------------
+Full documentation (syntax reference, how to use the language and the compiler, etc.) can be found at:
+https://prog8.readthedocs.io/
+
+
+What use Prog8 provide?
+-----------------------
+
+- reduction of source code length over raw assembly
 - 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
@@ -29,7 +38,7 @@ which aims to provide many conveniences over raw assembly code (even when using
 - inline assembly allows you to have full control when every cycle or byte matters
 - many built-in functions such as ``sin``, ``cos``, ``rnd``, ``abs``, ``min``, ``max``, ``sqrt``, ``msb``, ``rol``, ``ror``, ``swap``, ``memset``, ``memcopy``, ``sort`` and ``reverse``
 
-Rapid edit-compile-run-debug cycle:
+*Rapid edit-compile-run-debug cycle:*
 
 - use a modern PC to do the work on
 - very quick compilation times
@@ -37,15 +46,16 @@ Rapid edit-compile-run-debug cycle:
 - breakpoints, that let the Vice emulator drop into the monitor if execution hits them
 - source code labels automatically loaded in Vice emulator so it can show them in disassembly
 
-Prog8 is mainly targeted at the Commodore-64 machine at this time.
-Contributions to add support for other 8-bit (or other?!) machines are welcome.
+*Two supported compiler targets* (contributions to improve these or to add support for other machines are welcome!):
 
-Documentation/manual
---------------------
-https://prog8.readthedocs.io/
+- "c64": Commodore-64  (6510 CPU = almost a 6502)  premium support.
+- "cx16": [CommanderX16](https://www.commanderx16.com)  (65c02 CPU)  experimental support.
 
-Required tools
---------------
+
+
+
+Additional required tools
+-------------------------
 
 [64tass](https://sourceforge.net/projects/tass64/) - cross assembler. Install this on your shell path.
 A recent .exe version of this tool for Windows can be obtained from my [clone](https://github.com/irmen/64tass/releases) of this project.
@@ -55,8 +65,9 @@ A **Java runtime (jre or jdk), version 8 or newer**  is required to run a prepac
 If you want to build it from source, you'll need a Java SDK + Kotlin 1.3.x SDK (or for instance,
 IntelliJ IDEA with the Kotlin plugin).
 
-It's handy to have a C-64 emulator or a real C-64 to run the programs on. The compiler assumes the presence
-of the [Vice emulator](http://vice-emu.sourceforge.net/)
+It's handy to have an emulator (or a real machine perhaps!) to run the programs on. The compiler assumes the presence
+of the [Vice emulator](http://vice-emu.sourceforge.net/)  for the C64 target,
+and the [x16emu emulator](https://github.com/commanderx16/x16-emulator) for the CommanderX16 target.
 
 
 Example code
@@ -64,7 +75,7 @@ Example code
 
 This code calculates prime numbers using the Sieve of Eratosthenes algorithm::
 
-    %import c64utils
+    %import c64textio
     %zeropage basicsafe
 
     main {
@@ -73,35 +84,33 @@ This code calculates prime numbers using the Sieve of Eratosthenes algorithm::
         ubyte candidate_prime = 2
 
         sub start() {
-            memset(sieve, 256, false)
-
-            c64scr.print("prime numbers up to 255:\n\n")
+            memset(sieve, 256, false)   ; clear the sieve
+            txt.print("prime numbers up to 255:\n\n")
             ubyte amount=0
-            while true {
+            repeat {
                 ubyte prime = find_next_prime()
                 if prime==0
                     break
-                c64scr.print_ub(prime)
-                c64scr.print(", ")
+                txt.print_ub(prime)
+                txt.print(", ")
                 amount++
             }
             c64.CHROUT('\n')
-            c64scr.print("number of primes (expected 54): ")
-            c64scr.print_ub(amount)
+            txt.print("number of primes (expected 54): ")
+            txt.print_ub(amount)
             c64.CHROUT('\n')
         }
 
-
         sub find_next_prime() -> ubyte {
-
             while sieve[candidate_prime] {
                 candidate_prime++
                 if candidate_prime==0
-                    return 0
+                    return 0        ; we wrapped; no more primes available
             }
-
+            ; found next one, mark the multiples and return it.
             sieve[candidate_prime] = true
             uword multiple = candidate_prime
+
             while multiple < len(sieve) {
                 sieve[lsb(multiple)] = true
                 multiple += candidate_prime

compiler/build.gradle

@@ -1,11 +1,11 @@
 buildscript {
     dependencies {
-        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:1.3.72"
+        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:1.4.10"
     }
 }
 
 plugins {
-    // id "org.jetbrains.kotlin.jvm" version "1.3.72"
+    // id "org.jetbrains.kotlin.jvm" version "1.4.10"
     id 'application'
     id 'org.jetbrains.dokka' version "0.9.18"
     id 'com.github.johnrengelman.shadow' version '5.2.0'
@@ -110,3 +110,7 @@ dokka {
     outputFormat = 'html'
     outputDirectory = "$buildDir/kdoc"
 }
+
+task wrapper(type: Wrapper) {
+    gradleVersion = '6.1.1'
+}

compiler/res/prog8lib/c64floats.asm

@@ -1,49 +1,56 @@
 ; --- low level floating point assembly routines for the C64
 
+FL_ONE_const	.byte  129     			; 1.0
+FL_ZERO_const	.byte  0,0,0,0,0		; 0.0
+
+floats_store_reg	.byte  0		; temp storage
+
+
 ub2float	.proc
 		; -- convert ubyte in SCRATCH_ZPB1 to float at address A/Y
 		;    clobbers A, Y
-		stx  c64.SCRATCH_ZPREGX
-		sta  c64.SCRATCH_ZPWORD2
-		sty  c64.SCRATCH_ZPWORD2+1
-		ldy  c64.SCRATCH_ZPB1
-		jsr  FREADUY
-_fac_to_mem	ldx  c64.SCRATCH_ZPWORD2
-		ldy  c64.SCRATCH_ZPWORD2+1
+		stx  P8ZP_SCRATCH_REG
+		sta  P8ZP_SCRATCH_W2
+		sty  P8ZP_SCRATCH_W2+1
+		ldy  P8ZP_SCRATCH_B1
+		lda  #0
+		jsr  GIVAYF
+_fac_to_mem	ldx  P8ZP_SCRATCH_W2
+		ldy  P8ZP_SCRATCH_W2+1
 		jsr  MOVMF
-		ldx  c64.SCRATCH_ZPREGX
+		ldx  P8ZP_SCRATCH_REG
 		rts
 		.pend
 
 b2float		.proc
 		; -- convert byte in SCRATCH_ZPB1 to float at address A/Y
 		;    clobbers A, Y
-		stx  c64.SCRATCH_ZPREGX
-		sta  c64.SCRATCH_ZPWORD2
-		sty  c64.SCRATCH_ZPWORD2+1
-		lda  c64.SCRATCH_ZPB1
+		stx  P8ZP_SCRATCH_REG
+		sta  P8ZP_SCRATCH_W2
+		sty  P8ZP_SCRATCH_W2+1
+		lda  P8ZP_SCRATCH_B1
 		jsr  FREADSA
 		jmp  ub2float._fac_to_mem
 		.pend
 
 uw2float	.proc
 		; -- convert uword in SCRATCH_ZPWORD1 to float at address A/Y
-		stx  c64.SCRATCH_ZPREGX
-		sta  c64.SCRATCH_ZPWORD2
-		sty  c64.SCRATCH_ZPWORD2+1
-		lda  c64.SCRATCH_ZPWORD1
-		ldy  c64.SCRATCH_ZPWORD1+1
+		stx  P8ZP_SCRATCH_REG
+		sta  P8ZP_SCRATCH_W2
+		sty  P8ZP_SCRATCH_W2+1
+		lda  P8ZP_SCRATCH_W1
+		ldy  P8ZP_SCRATCH_W1+1
 		jsr  GIVUAYFAY
 		jmp  ub2float._fac_to_mem
 		.pend
 
 w2float		.proc
 		; -- convert word in SCRATCH_ZPWORD1 to float at address A/Y
-		stx  c64.SCRATCH_ZPREGX
-		sta  c64.SCRATCH_ZPWORD2
-		sty  c64.SCRATCH_ZPWORD2+1
-		ldy  c64.SCRATCH_ZPWORD1
-		lda  c64.SCRATCH_ZPWORD1+1
+		stx  P8ZP_SCRATCH_REG
+		sta  P8ZP_SCRATCH_W2
+		sty  P8ZP_SCRATCH_W2+1
+		ldy  P8ZP_SCRATCH_W1
+		lda  P8ZP_SCRATCH_W1+1
 		jsr  GIVAYF
 		jmp  ub2float._fac_to_mem
 		.pend
@@ -51,8 +58,8 @@ w2float		.proc
 stack_b2float	.proc
 		; -- b2float operating on the stack
 		inx
-		lda  c64.ESTACK_LO,x
-		stx  c64.SCRATCH_ZPREGX
+		lda  P8ESTACK_LO,x
+		stx  P8ZP_SCRATCH_REG
 		jsr  FREADSA
 		jmp  push_fac1_as_result
 		.pend
@@ -60,9 +67,9 @@ stack_b2float	.proc
 stack_w2float	.proc
 		; -- w2float operating on the stack
 		inx
-		ldy  c64.ESTACK_LO,x
-		lda  c64.ESTACK_HI,x
-		stx  c64.SCRATCH_ZPREGX
+		ldy  P8ESTACK_LO,x
+		lda  P8ESTACK_HI,x
+		stx  P8ZP_SCRATCH_REG
 		jsr  GIVAYF
 		jmp  push_fac1_as_result
 		.pend
@@ -70,44 +77,45 @@ stack_w2float	.proc
 stack_ub2float	.proc
 		; -- ub2float operating on the stack
 		inx
-		lda  c64.ESTACK_LO,x
-		stx  c64.SCRATCH_ZPREGX
+		lda  P8ESTACK_LO,x
+		stx  P8ZP_SCRATCH_REG
 		tay
-		jsr  FREADUY
+		lda  #0
+		jsr  GIVAYF
 		jmp  push_fac1_as_result
 		.pend
 
 stack_uw2float	.proc
 		; -- uw2float operating on the stack
 		inx
-		lda  c64.ESTACK_LO,x
-		ldy  c64.ESTACK_HI,x
-		stx  c64.SCRATCH_ZPREGX
+		lda  P8ESTACK_LO,x
+		ldy  P8ESTACK_HI,x
+		stx  P8ZP_SCRATCH_REG
 		jsr  GIVUAYFAY
 		jmp  push_fac1_as_result
 		.pend
 
 stack_float2w	.proc               ; also used for float2b
 		jsr  pop_float_fac1
-		stx  c64.SCRATCH_ZPREGX
+		stx  P8ZP_SCRATCH_REG
 		jsr  AYINT
-		ldx  c64.SCRATCH_ZPREGX
+		ldx  P8ZP_SCRATCH_REG
 		lda  $64
-		sta  c64.ESTACK_HI,x
+		sta  P8ESTACK_HI,x
 		lda  $65
-		sta  c64.ESTACK_LO,x
+		sta  P8ESTACK_LO,x
 		dex
 		rts
 		.pend
 
 stack_float2uw	.proc               ; also used for float2ub
 		jsr  pop_float_fac1
-		stx  c64.SCRATCH_ZPREGX
+		stx  P8ZP_SCRATCH_REG
 		jsr  GETADR
-		ldx  c64.SCRATCH_ZPREGX
-		sta  c64.ESTACK_HI,x
+		ldx  P8ZP_SCRATCH_REG
+		sta  P8ESTACK_HI,x
 		tya
-		sta  c64.ESTACK_LO,x
+		sta  P8ESTACK_LO,x
 		dex
 		rts
 		.pend
@@ -115,79 +123,68 @@ stack_float2uw	.proc               ; also used for float2ub
 push_float	.proc
 		; ---- push mflpt5 in A/Y onto stack
 		; (taking 3 stack positions = 6 bytes of which 1 is padding)
-		sta  c64.SCRATCH_ZPWORD1
-		sty  c64.SCRATCH_ZPWORD1+1
+		sta  P8ZP_SCRATCH_W1
+		sty  P8ZP_SCRATCH_W1+1
 		ldy  #0
-		lda  (c64.SCRATCH_ZPWORD1),y
-		sta  c64.ESTACK_LO,x
+		lda  (P8ZP_SCRATCH_W1),y
+		sta  P8ESTACK_LO,x
 		iny
-		lda  (c64.SCRATCH_ZPWORD1),y
-		sta  c64.ESTACK_HI,x
+		lda  (P8ZP_SCRATCH_W1),y
+		sta  P8ESTACK_HI,x
 		dex
 		iny
-		lda  (c64.SCRATCH_ZPWORD1),y
-		sta  c64.ESTACK_LO,x
+		lda  (P8ZP_SCRATCH_W1),y
+		sta  P8ESTACK_LO,x
 		iny
-		lda  (c64.SCRATCH_ZPWORD1),y
-		sta  c64.ESTACK_HI,x
+		lda  (P8ZP_SCRATCH_W1),y
+		sta  P8ESTACK_HI,x
 		dex
 		iny
-		lda  (c64.SCRATCH_ZPWORD1),y
-		sta  c64.ESTACK_LO,x
+		lda  (P8ZP_SCRATCH_W1),y
+		sta  P8ESTACK_LO,x
 		dex
 		rts
 		.pend
 
 func_rndf	.proc
 		; -- put a random floating point value on the stack
-		stx  c64.SCRATCH_ZPREG
+		stx  P8ZP_SCRATCH_REG
 		lda  #1
 		jsr  FREADSA
 		jsr  RND		; rng into fac1
 		ldx  #<_rndf_rnum5
 		ldy  #>_rndf_rnum5
 		jsr  MOVMF	; fac1 to mem X/Y
-		ldx  c64.SCRATCH_ZPREG
+		ldx  P8ZP_SCRATCH_REG
 		lda  #<_rndf_rnum5
 		ldy  #>_rndf_rnum5
 		jmp  push_float
 _rndf_rnum5	.byte  0,0,0,0,0
 		.pend
 
-push_float_from_indexed_var	.proc
-		; -- push the float from the array at A/Y with index on stack, onto the stack.
-		sta  c64.SCRATCH_ZPWORD1
-		sty  c64.SCRATCH_ZPWORD1+1
-		jsr  prog8_lib.pop_index_times_5
-		jsr  prog8_lib.add_a_to_zpword
-		lda  c64.SCRATCH_ZPWORD1
-		ldy  c64.SCRATCH_ZPWORD1+1
-		jmp  push_float
-		.pend
-
 pop_float	.proc
 		; ---- pops mflpt5 from stack to memory A/Y
 		; (frees 3 stack positions = 6 bytes of which 1 is padding)
-		sta  c64.SCRATCH_ZPWORD1
-		sty  c64.SCRATCH_ZPWORD1+1
+		sta  P8ZP_SCRATCH_W1
+		sty  P8ZP_SCRATCH_W1+1
 		ldy  #4
 		inx
-		lda  c64.ESTACK_LO,x
-		sta  (c64.SCRATCH_ZPWORD1),y
+		lda  P8ESTACK_LO,x
+		sta  (P8ZP_SCRATCH_W1),y
 		dey
 		inx
-		lda  c64.ESTACK_HI,x
-		sta  (c64.SCRATCH_ZPWORD1),y
+		lda  P8ESTACK_HI,x
+		sta  (P8ZP_SCRATCH_W1),y
 		dey
-		lda  c64.ESTACK_LO,x
-		sta  (c64.SCRATCH_ZPWORD1),y
+		lda  P8ESTACK_LO,x
+		sta  (P8ZP_SCRATCH_W1),y
 		dey
 		inx
-		lda  c64.ESTACK_HI,x
-		sta  (c64.SCRATCH_ZPWORD1),y
+		lda  P8ESTACK_HI,x
+		sta  (P8ZP_SCRATCH_W1),y
 		dey
-		lda  c64.ESTACK_LO,x
-		sta  (c64.SCRATCH_ZPWORD1),y
+		lda  P8ESTACK_LO,x
+		sta  (P8ZP_SCRATCH_W1),y
 		rts
 		.pend
 
@@ -201,110 +198,74 @@ pop_float_fac1	.proc
 		jmp  MOVFM
 		.pend
 
+pop_float_fac2	.proc
+		; -- pops float from stack into FAC2
+		lda  #<fmath_float1
+		ldy  #>fmath_float1
+		jsr  pop_float
+		lda  #<fmath_float1
+		ldy  #>fmath_float1
+		jmp  CONUPK
+		.pend
+
 pop_float_to_indexed_var	.proc
 		; -- pop the float on the stack, to the memory in the array at A/Y indexed by the byte on stack
-		sta  c64.SCRATCH_ZPWORD1
-		sty  c64.SCRATCH_ZPWORD1+1
+		sta  P8ZP_SCRATCH_W1
+		sty  P8ZP_SCRATCH_W1+1
 		jsr  prog8_lib.pop_index_times_5
 		jsr  prog8_lib.add_a_to_zpword
-		lda  c64.SCRATCH_ZPWORD1
-		ldy  c64.SCRATCH_ZPWORD1+1
+		lda  P8ZP_SCRATCH_W1
+		ldy  P8ZP_SCRATCH_W1+1
 		jmp  pop_float
 		.pend
 
 copy_float	.proc
 		; -- copies the 5 bytes of the mflt value pointed to by SCRATCH_ZPWORD1,
 		;    into the 5 bytes pointed to by A/Y.  Clobbers A,Y.
-		sta  c64.SCRATCH_ZPWORD2
-		sty  c64.SCRATCH_ZPWORD2+1
-		ldy  #0
-		lda  (c64.SCRATCH_ZPWORD1),y
-		sta  (c64.SCRATCH_ZPWORD2),y
-		iny
-		lda  (c64.SCRATCH_ZPWORD1),y
-		sta  (c64.SCRATCH_ZPWORD2),y
-		iny
-		lda  (c64.SCRATCH_ZPWORD1),y
-		sta  (c64.SCRATCH_ZPWORD2),y
-		iny
-		lda  (c64.SCRATCH_ZPWORD1),y
-		sta  (c64.SCRATCH_ZPWORD2),y
-		iny
-		lda  (c64.SCRATCH_ZPWORD1),y
-		sta  (c64.SCRATCH_ZPWORD2),y
+		sta  _target+1
+		sty  _target+2
+		ldy  #4
+_loop		lda  (P8ZP_SCRATCH_W1),y
+_target		sta  $ffff,y			; modified
+		dey
+		bpl  _loop
 		rts
 		.pend
 
 inc_var_f	.proc
 		; -- add 1 to float pointed to by A/Y
-		sta  c64.SCRATCH_ZPWORD1
-		sty  c64.SCRATCH_ZPWORD1+1
-		stx  c64.SCRATCH_ZPREGX
+		sta  P8ZP_SCRATCH_W1
+		sty  P8ZP_SCRATCH_W1+1
+		stx  P8ZP_SCRATCH_REG
 		jsr  MOVFM
-		lda  #<FL_FONE
-		ldy  #>FL_FONE
+		lda  #<FL_ONE_const
+		ldy  #>FL_ONE_const
 		jsr  FADD
-		ldx  c64.SCRATCH_ZPWORD1
-		ldy  c64.SCRATCH_ZPWORD1+1
+		ldx  P8ZP_SCRATCH_W1
+		ldy  P8ZP_SCRATCH_W1+1
 		jsr  MOVMF
-		ldx  c64.SCRATCH_ZPREGX
+		ldx  P8ZP_SCRATCH_REG
 		rts
 		.pend
 
 dec_var_f	.proc
 		; -- subtract 1 from float pointed to by A/Y
-		sta  c64.SCRATCH_ZPWORD1
-		sty  c64.SCRATCH_ZPWORD1+1
-		stx  c64.SCRATCH_ZPREGX
-		lda  #<FL_FONE
-		ldy  #>FL_FONE
+		sta  P8ZP_SCRATCH_W1
+		sty  P8ZP_SCRATCH_W1+1
+		stx  P8ZP_SCRATCH_REG
+		lda  #<FL_ONE_const
+		ldy  #>FL_ONE_const
 		jsr  MOVFM
-		lda  c64.SCRATCH_ZPWORD1
-		ldy  c64.SCRATCH_ZPWORD1+1
+		lda  P8ZP_SCRATCH_W1
+		ldy  P8ZP_SCRATCH_W1+1
 		jsr  FSUB
-		ldx  c64.SCRATCH_ZPWORD1
-		ldy  c64.SCRATCH_ZPWORD1+1
+		ldx  P8ZP_SCRATCH_W1
+		ldy  P8ZP_SCRATCH_W1+1
 		jsr  MOVMF
-		ldx  c64.SCRATCH_ZPREGX
+		ldx  P8ZP_SCRATCH_REG
 		rts
 		.pend
 
-inc_indexed_var_f	.proc
-		; -- add 1 to float in array pointed to by A/Y, at index X
-		pha
-		txa
-		sta  c64.SCRATCH_ZPB1
-		asl  a
-		asl  a
-		clc
-		adc  c64.SCRATCH_ZPB1
-		sta  c64.SCRATCH_ZPB1
-		pla
-		clc
-		adc  c64.SCRATCH_ZPB1
-		bcc  +
-		iny
-+		jmp  inc_var_f
-		.pend
-
-dec_indexed_var_f	.proc
-		; -- subtract 1 to float in array pointed to by A/Y, at index X
-		pha
-		txa
-		sta  c64.SCRATCH_ZPB1
-		asl  a
-		asl  a
-		clc
-		adc  c64.SCRATCH_ZPB1
-		sta  c64.SCRATCH_ZPB1
-		pla
-		clc
-		adc  c64.SCRATCH_ZPB1
-		bcc  +
-		iny
-+		jmp  dec_var_f
-		.pend
-
 
 pop_2_floats_f2_in_fac1	.proc
 		; -- pop 2 floats from stack, load the second one in FAC1 as well
@@ -330,7 +291,7 @@ push_fac1_as_result	.proc
 		jsr  MOVMF
 		lda  #<fmath_float1
 		ldy  #>fmath_float1
-		ldx  c64.SCRATCH_ZPREGX
+		ldx  P8ZP_SCRATCH_REG
 		jmp  push_float
 		.pend
 
@@ -342,21 +303,21 @@ pow_f		.proc
 		lda  #<fmath_float1
 		ldy  #>fmath_float1
 		jsr  pop_float
-		stx  c64.SCRATCH_ZPREGX
+		stx  P8ZP_SCRATCH_REG
 		lda  #<fmath_float1
 		ldy  #>fmath_float1
 		jsr  CONUPK		; fac2 = float1
 		lda  #<fmath_float2
 		ldy  #>fmath_float2
 		jsr  FPWR
-		ldx  c64.SCRATCH_ZPREGX
+		ldx  P8ZP_SCRATCH_REG
 		jmp  push_fac1_as_result
 		.pend
 
 div_f		.proc
 		; -- push f1/f2 on stack
 		jsr  pop_2_floats_f2_in_fac1
-		stx  c64.SCRATCH_ZPREGX
+		stx  P8ZP_SCRATCH_REG
 		lda  #<fmath_float1
 		ldy  #>fmath_float1
 		jsr  FDIV
@@ -366,7 +327,7 @@ div_f		.proc
 add_f		.proc
 		; -- push f1+f2 on stack
 		jsr  pop_2_floats_f2_in_fac1
-		stx  c64.SCRATCH_ZPREGX
+		stx  P8ZP_SCRATCH_REG
 		lda  #<fmath_float1
 		ldy  #>fmath_float1
 		jsr  FADD
@@ -376,7 +337,7 @@ add_f		.proc
 sub_f		.proc
 		; -- push f1-f2 on stack
 		jsr  pop_2_floats_f2_in_fac1
-		stx  c64.SCRATCH_ZPREGX
+		stx  P8ZP_SCRATCH_REG
 		lda  #<fmath_float1
 		ldy  #>fmath_float1
 		jsr  FSUB
@@ -386,7 +347,7 @@ sub_f		.proc
 mul_f		.proc
 		; -- push f1*f2 on stack
 		jsr  pop_2_floats_f2_in_fac1
-		stx  c64.SCRATCH_ZPREGX
+		stx  P8ZP_SCRATCH_REG
 		lda  #<fmath_float1
 		ldy  #>fmath_float1
 		jsr  FMULT
@@ -396,7 +357,7 @@ mul_f		.proc
 neg_f		.proc
 		; -- push -flt back on stack
 		jsr  pop_float_fac1
-		stx  c64.SCRATCH_ZPREGX
+		stx  P8ZP_SCRATCH_REG
 		jsr  NEGOP
 		jmp  push_fac1_as_result
 		.pend
@@ -404,7 +365,7 @@ neg_f		.proc
 abs_f		.proc
 		; -- push abs(float) on stack (as float)
 		jsr  pop_float_fac1
-		stx  c64.SCRATCH_ZPREGX
+		stx  P8ZP_SCRATCH_REG
 		jsr  ABS
 		jmp  push_fac1_as_result
 		.pend
@@ -415,24 +376,24 @@ equal_f		.proc
 		inx
 		inx
 		inx
-		lda  c64.ESTACK_LO-3,x
-		cmp  c64.ESTACK_LO,x
+		lda  P8ESTACK_LO-3,x
+		cmp  P8ESTACK_LO,x
 		bne  _equals_false
-		lda  c64.ESTACK_LO-2,x
-		cmp  c64.ESTACK_LO+1,x
+		lda  P8ESTACK_LO-2,x
+		cmp  P8ESTACK_LO+1,x
 		bne  _equals_false
-		lda  c64.ESTACK_LO-1,x
-		cmp  c64.ESTACK_LO+2,x
+		lda  P8ESTACK_LO-1,x
+		cmp  P8ESTACK_LO+2,x
 		bne  _equals_false
-		lda  c64.ESTACK_HI-2,x
-		cmp  c64.ESTACK_HI+1,x
+		lda  P8ESTACK_HI-2,x
+		cmp  P8ESTACK_HI+1,x
 		bne  _equals_false
-		lda  c64.ESTACK_HI-1,x
-		cmp  c64.ESTACK_HI+2,x
+		lda  P8ESTACK_HI-1,x
+		cmp  P8ESTACK_HI+2,x
 		bne  _equals_false
 _equals_true	lda  #1
 _equals_store	inx
-		sta  c64.ESTACK_LO+1,x
+		sta  P8ESTACK_LO+1,x
 		rts
 _equals_false	lda  #0
 		beq  _equals_store
@@ -442,7 +403,7 @@ notequal_f	.proc
 		; -- are the two mflpt5 numbers on the stack different?
 		jsr  equal_f
 		eor  #1		; invert the result
-		sta  c64.ESTACK_LO+1,x
+		sta  P8ESTACK_LO+1,x
 		rts
 		.pend
 
@@ -495,12 +456,12 @@ compare_floats	.proc
 		jsr  MOVFM		; fac1 = flt1
 		lda  #<fmath_float2
 		ldy  #>fmath_float2
-		stx  c64.SCRATCH_ZPREG
+		stx  P8ZP_SCRATCH_REG
 		jsr  FCOMP		; A = flt1 compared with flt2 (0=equal, 1=flt1>flt2, 255=flt1<flt2)
-		ldx  c64.SCRATCH_ZPREG
+		ldx  P8ZP_SCRATCH_REG
 		rts
 _return_false	lda  #0
-_return_result  sta  c64.ESTACK_LO,x
+_return_result  sta  P8ESTACK_LO,x
 		dex
 		rts
 _return_true	lda  #1
@@ -510,7 +471,7 @@ _return_true	lda  #1
 func_sin	.proc
 		; -- push sin(f) back onto stack
 		jsr  pop_float_fac1
-		stx  c64.SCRATCH_ZPREGX
+		stx  P8ZP_SCRATCH_REG
 		jsr  SIN
 		jmp  push_fac1_as_result
 		.pend
@@ -518,7 +479,7 @@ func_sin	.proc
 func_cos	.proc
 		; -- push cos(f) back onto stack
 		jsr  pop_float_fac1
-		stx  c64.SCRATCH_ZPREGX
+		stx  P8ZP_SCRATCH_REG
 		jsr  COS
 		jmp  push_fac1_as_result
 		.pend
@@ -526,7 +487,7 @@ func_cos	.proc
 func_tan	.proc
 		; -- push tan(f) back onto stack
 		jsr  pop_float_fac1
-		stx  c64.SCRATCH_ZPREGX
+		stx  P8ZP_SCRATCH_REG
 		jsr  TAN
 		jmp  push_fac1_as_result
 		.pend
@@ -534,7 +495,7 @@ func_tan	.proc
 func_atan	.proc
 		; -- push atan(f) back onto stack
 		jsr  pop_float_fac1
-		stx  c64.SCRATCH_ZPREGX
+		stx  P8ZP_SCRATCH_REG
 		jsr  ATN
 		jmp  push_fac1_as_result
 		.pend
@@ -542,7 +503,7 @@ func_atan	.proc
 func_ln		.proc
 		; -- push ln(f) back onto stack
 		jsr  pop_float_fac1
-		stx  c64.SCRATCH_ZPREGX
+		stx  P8ZP_SCRATCH_REG
 		jsr  LOG
 		jmp  push_fac1_as_result
 		.pend
@@ -550,7 +511,7 @@ func_ln		.proc
 func_log2	.proc
 		; -- push log base 2, ln(f)/ln(2), back onto stack
 		jsr  pop_float_fac1
-		stx  c64.SCRATCH_ZPREGX
+		stx  P8ZP_SCRATCH_REG
 		jsr  LOG
 		jsr  MOVEF
 		lda  #<c64.FL_LOG2
@@ -562,7 +523,7 @@ func_log2	.proc
 
 func_sqrt	.proc
 		jsr  pop_float_fac1
-		stx  c64.SCRATCH_ZPREGX
+		stx  P8ZP_SCRATCH_REG
 		jsr  SQR
 		jmp  push_fac1_as_result
 		.pend
@@ -570,7 +531,7 @@ func_sqrt	.proc
 func_rad	.proc
 		; -- convert degrees to radians (d * pi / 180)
 		jsr  pop_float_fac1
-		stx  c64.SCRATCH_ZPREGX
+		stx  P8ZP_SCRATCH_REG
 		lda  #<_pi_div_180
 		ldy  #>_pi_div_180
 		jsr  FMULT
@@ -581,7 +542,7 @@ _pi_div_180	.byte 123, 14, 250, 53, 18		; pi / 180
 func_deg	.proc
 		; -- convert radians to degrees (d * (1/ pi * 180))
 		jsr  pop_float_fac1
-		stx  c64.SCRATCH_ZPREGX
+		stx  P8ZP_SCRATCH_REG
 		lda  #<_one_over_pi_div_180
 		ldy  #>_one_over_pi_div_180
 		jsr  FMULT
@@ -591,7 +552,7 @@ _one_over_pi_div_180	.byte 134, 101, 46, 224, 211		; 1 / (pi * 180)
 
 func_round	.proc
 		jsr  pop_float_fac1
-		stx  c64.SCRATCH_ZPREGX
+		stx  P8ZP_SCRATCH_REG
 		jsr  FADDH
 		jsr  INT
 		jmp  push_fac1_as_result
@@ -599,7 +560,7 @@ func_round	.proc
 
 func_floor	.proc
 		jsr  pop_float_fac1
-		stx  c64.SCRATCH_ZPREGX
+		stx  P8ZP_SCRATCH_REG
 		jsr  INT
 		jmp  push_fac1_as_result
 		.pend
@@ -607,7 +568,7 @@ func_floor	.proc
 func_ceil	.proc
 		; -- ceil: tr = int(f); if tr==f -> return  else return tr+1
 		jsr  pop_float_fac1
-		stx  c64.SCRATCH_ZPREGX
+		stx  P8ZP_SCRATCH_REG
 		ldx  #<fmath_float1
 		ldy  #>fmath_float1
 		jsr  MOVMF
@@ -617,53 +578,53 @@ func_ceil	.proc
 		jsr  FCOMP
 		cmp  #0
 		beq  +
-		lda  #<FL_FONE
-		ldy  #>FL_FONE
+		lda  #<FL_ONE_const
+		ldy  #>FL_ONE_const
 		jsr  FADD
 +		jmp  push_fac1_as_result
 		.pend
 
 func_any_f	.proc
 		inx
-		lda  c64.ESTACK_LO,x	; array size
-		sta  c64.SCRATCH_ZPB1
+		lda  P8ESTACK_LO,x	; array size
+		sta  P8ZP_SCRATCH_B1
 		asl  a
 		asl  a
 		clc
-		adc  c64.SCRATCH_ZPB1	; times 5 because of float
+		adc  P8ZP_SCRATCH_B1	; times 5 because of float
 		jmp  prog8_lib.func_any_b._entry
 		.pend
 
 func_all_f	.proc
 		inx
 		jsr  prog8_lib.peek_address
-		lda  c64.ESTACK_LO,x	; array size
-		sta  c64.SCRATCH_ZPB1
+		lda  P8ESTACK_LO,x	; array size
+		sta  P8ZP_SCRATCH_B1
 		asl  a
 		asl  a
 		clc
-		adc  c64.SCRATCH_ZPB1	; times 5 because of float
+		adc  P8ZP_SCRATCH_B1	; times 5 because of float
 		tay
 		dey
--		lda  (c64.SCRATCH_ZPWORD1),y
+-		lda  (P8ZP_SCRATCH_W1),y
 		clc
 		dey
-		adc  (c64.SCRATCH_ZPWORD1),y
+		adc  (P8ZP_SCRATCH_W1),y
 		dey
-		adc  (c64.SCRATCH_ZPWORD1),y
+		adc  (P8ZP_SCRATCH_W1),y
 		dey
-		adc  (c64.SCRATCH_ZPWORD1),y
+		adc  (P8ZP_SCRATCH_W1),y
 		dey
-		adc  (c64.SCRATCH_ZPWORD1),y
+		adc  (P8ZP_SCRATCH_W1),y
 		dey
 		cmp  #0
 		beq  +
 		cpy  #255
         	bne  -
 		lda  #1
-		sta  c64.ESTACK_LO+1,x
+		sta  P8ESTACK_LO+1,x
 		rts
-+		sta  c64.ESTACK_LO+1,x
++		sta  P8ESTACK_LO+1,x
 		rts
 		.pend
 
@@ -674,26 +635,28 @@ func_max_f	.proc
 		ldy  #>_largest_neg_float
 _minmax_entry	jsr  MOVFM
 		jsr  prog8_lib.pop_array_and_lengthmin1Y
-		stx  c64.SCRATCH_ZPREGX
--		sty  c64.SCRATCH_ZPREG
-		lda  c64.SCRATCH_ZPWORD1
-		ldy  c64.SCRATCH_ZPWORD1+1
+		stx  floats_store_reg
+-		sty  P8ZP_SCRATCH_REG
+		lda  P8ZP_SCRATCH_W1
+		ldy  P8ZP_SCRATCH_W1+1
 		jsr  FCOMP
 _minmax_cmp	cmp  #255			; modified
 		bne  +
-		lda  c64.SCRATCH_ZPWORD1
-		ldy  c64.SCRATCH_ZPWORD1+1
+		lda  P8ZP_SCRATCH_W1
+		ldy  P8ZP_SCRATCH_W1+1
 		jsr  MOVFM
-+		lda  c64.SCRATCH_ZPWORD1
++		lda  P8ZP_SCRATCH_W1
 		clc
 		adc  #5
-		sta  c64.SCRATCH_ZPWORD1
+		sta  P8ZP_SCRATCH_W1
 		bcc  +
-		inc  c64.SCRATCH_ZPWORD1+1
-+		ldy  c64.SCRATCH_ZPREG
+		inc  P8ZP_SCRATCH_W1+1
++		ldy  P8ZP_SCRATCH_REG
 		dey
 		cpy  #255
 		bne  -
+		ldx  floats_store_reg
+		stx  P8ZP_SCRATCH_REG
 		jmp  push_fac1_as_result
 _largest_neg_float	.byte 255,255,255,255,255		; largest negative float -1.7014118345e+38
 		.pend
@@ -709,33 +672,35 @@ _largest_pos_float	.byte  255,127,255,255,255		; largest positive float
 		.pend
 
 func_sum_f	.proc
-		lda  #<FL_ZERO
-		ldy  #>FL_ZERO
+		lda  #<FL_ZERO_const
+		ldy  #>FL_ZERO_const
 		jsr  MOVFM
 		jsr  prog8_lib.pop_array_and_lengthmin1Y
-		stx  c64.SCRATCH_ZPREGX
--		sty  c64.SCRATCH_ZPREG
-		lda  c64.SCRATCH_ZPWORD1
-		ldy  c64.SCRATCH_ZPWORD1+1
+		stx  floats_store_reg
+-		sty  P8ZP_SCRATCH_REG
+		lda  P8ZP_SCRATCH_W1
+		ldy  P8ZP_SCRATCH_W1+1
 		jsr  FADD
-		ldy  c64.SCRATCH_ZPREG
+		ldy  P8ZP_SCRATCH_REG
 		dey
 		cpy  #255
 		beq  +
-		lda  c64.SCRATCH_ZPWORD1
+		lda  P8ZP_SCRATCH_W1
 		clc
 		adc  #5
-		sta  c64.SCRATCH_ZPWORD1
+		sta  P8ZP_SCRATCH_W1
 		bcc  -
-		inc  c64.SCRATCH_ZPWORD1+1
+		inc  P8ZP_SCRATCH_W1+1
 		bne  -
-+		jmp  push_fac1_as_result
++		ldx  floats_store_reg
+		stx  P8ZP_SCRATCH_REG
+		jmp  push_fac1_as_result
 		.pend
 
 sign_f		.proc
 		jsr  pop_float_fac1
 		jsr  SIGN
-		sta  c64.ESTACK_LO,x
+		sta  P8ESTACK_LO,x
 		dex
 		rts
 		.pend
@@ -744,22 +709,22 @@ sign_f		.proc
 set_0_array_float	.proc
 		; -- set a float in an array to zero (index on stack, array in SCRATCH_ZPWORD1)
 		inx
-		lda  c64.ESTACK_LO,x
+		lda  P8ESTACK_LO,x
 		asl  a
 		asl  a
 		clc
-		adc  c64.ESTACK_LO,x
+		adc  P8ESTACK_LO,x
 		tay
 		lda  #0
-		sta  (c64.SCRATCH_ZPWORD1),y
+		sta  (P8ZP_SCRATCH_W1),y
 		iny
-		sta  (c64.SCRATCH_ZPWORD1),y
+		sta  (P8ZP_SCRATCH_W1),y
 		iny
-		sta  (c64.SCRATCH_ZPWORD1),y
+		sta  (P8ZP_SCRATCH_W1),y
 		iny
-		sta  (c64.SCRATCH_ZPWORD1),y
+		sta  (P8ZP_SCRATCH_W1),y
 		iny
-		sta  (c64.SCRATCH_ZPWORD1),y
+		sta  (P8ZP_SCRATCH_W1),y
 		rts
 		.pend
 
@@ -767,14 +732,13 @@ set_0_array_float	.proc
 set_array_float		.proc
 		; -- set a float in an array to a value (index on stack, float in SCRATCH_ZPWORD1, array in SCRATCH_ZPWORD2)
 		inx
-		lda  c64.ESTACK_LO,x
+		lda  P8ESTACK_LO,x
 		asl  a
 		asl  a
 		clc
-		adc  c64.ESTACK_LO,x
-		clc
-		adc  c64.SCRATCH_ZPWORD2
-		ldy  c64.SCRATCH_ZPWORD2+1
+		adc  P8ESTACK_LO,x
+		adc  P8ZP_SCRATCH_W2
+		ldy  P8ZP_SCRATCH_W2+1
 		bcc  +
 		iny
 +		jmp  copy_float
@@ -786,12 +750,12 @@ set_array_float		.proc
 swap_floats	.proc
 		; -- swap floats pointed to by SCRATCH_ZPWORD1, SCRATCH_ZPWORD2
 		ldy  #4
--               lda  (c64.SCRATCH_ZPWORD1),y
+-               lda  (P8ZP_SCRATCH_W1),y
 		pha
-		lda  (c64.SCRATCH_ZPWORD2),y
-		sta  (c64.SCRATCH_ZPWORD1),y
+		lda  (P8ZP_SCRATCH_W2),y
+		sta  (P8ZP_SCRATCH_W1),y
 		pla
-		sta  (c64.SCRATCH_ZPWORD2),y
+		sta  (P8ZP_SCRATCH_W2),y
 		dey
 		bpl  -
 		rts

compiler/res/prog8lib/c64flt.p8

@@ -4,14 +4,14 @@
 ;
 ; indent format: TABS, size=8
 
+%target c64
 %option enable_floats
 
-
 c64flt {
 	; ---- this block contains C-64 floating point related functions ----
 
-        const  float  PI        = 3.141592653589793
-        const  float  TWOPI	    = 6.283185307179586
+        const float  PI     = 3.141592653589793
+        const float  TWOPI  = 6.283185307179586
 
 
 ; ---- C64 basic and kernal ROM float constants and functions ----
@@ -35,13 +35,11 @@ c64flt {
 		&float  FL_TWOPI	= $e2e5  ; 2 * PI
 		&float  FL_FR4		= $e2ea  ; .25
 		; oddly enough, 0.0 isn't available in the kernel.
-        float   FL_ZERO     = 0.0    ; oddly enough 0.0 isn't available in the kernel
 
 
 ; note: fac1/2 might get clobbered even if not mentioned in the function's name.
 ; note: for subtraction and division, the left operand is in fac2, the right operand in fac1.
 
-; checked functions below:
 romsub $bba2 = MOVFM(uword mflpt @ AY) clobbers(A,Y)        ; load mflpt value from memory  in A/Y into fac1
 romsub $bba6 = FREADMEM() clobbers(A,Y)                     ; load mflpt value from memory  in $22/$23 into fac1
 romsub $ba8c = CONUPK(uword mflpt @ AY) clobbers(A,Y)       ; load mflpt value from memory  in A/Y into fac2
@@ -91,6 +89,7 @@ romsub $bb12 = FDIVT() clobbers(A,X,Y)                      ; fac1 = fac2/fac1
 romsub $bb0f = FDIV(uword mflpt @ AY) clobbers(A,X,Y)       ; fac1 = mflpt in A/Y / fac1  (remainder in fac2)
 romsub $bf7b = FPWRT() clobbers(A,X,Y)                      ; fac1 = fac2 ** fac1
 romsub $bf78 = FPWR(uword mflpt @ AY) clobbers(A,X,Y)       ; fac1 = fac2 ** mflpt from A/Y
+romsub $bd7e = FINLOG(byte value @A) clobbers (A, X, Y)     ; fac1 += signed byte in A
 
 romsub $aed4 = NOTOP() clobbers(A,X,Y)                      ; fac1 = NOT(fac1)
 romsub $bccc = INT() clobbers(A,X,Y)                        ; INT() truncates, use FADDH first to round instead of trunc
@@ -163,9 +162,9 @@ asmsub  GIVUAYFAY  (uword value @ AY) clobbers(A,X,Y)  {
 asmsub  GIVAYFAY  (uword value @ AY) clobbers(A,X,Y)  {
 	; ---- signed 16 bit word in A/Y (lo/hi) to float in fac1
 	%asm {{
-		sta  c64.SCRATCH_ZPREG
+		sta  P8ZP_SCRATCH_REG
 		tya
-		ldy  c64.SCRATCH_ZPREG
+		ldy  P8ZP_SCRATCH_REG
 		jmp  GIVAYF		; this uses the inverse order, Y/A
 	}}
 }
@@ -174,9 +173,9 @@ asmsub  FTOSWRDAY  () clobbers(X) -> uword @ AY  {
 	; ---- fac1 to signed word in A/Y
 	%asm {{
 		jsr  FTOSWORDYA	; note the inverse Y/A order
-		sta  c64.SCRATCH_ZPREG
+		sta  P8ZP_SCRATCH_REG
 		tya
-		ldy  c64.SCRATCH_ZPREG
+		ldy  P8ZP_SCRATCH_REG
 		rts
 	}}
 }
@@ -185,41 +184,34 @@ asmsub  GETADRAY  () clobbers(X) -> uword @ AY  {
 	; ---- fac1 to unsigned word in A/Y
 	%asm {{
 		jsr  GETADR		; this uses the inverse order, Y/A
-		sta  c64.SCRATCH_ZPB1
+		sta  P8ZP_SCRATCH_B1
 		tya
-		ldy  c64.SCRATCH_ZPB1
+		ldy  P8ZP_SCRATCH_B1
 		rts
 	}}
 }
 
 sub  print_f  (float value) {
-	; ---- prints the floating point value (without a newline) using basic rom routines.
+	; ---- prints the floating point value (without a newline).
 	%asm {{
-		stx  c64.SCRATCH_ZPREGX
+		stx  floats_store_reg
 		lda  #<value
 		ldy  #>value
 		jsr  MOVFM		; load float into fac1
 		jsr  FOUT		; fac1 to string in A/Y
-		jsr  c64.STROUT			; print string in A/Y
-		ldx  c64.SCRATCH_ZPREGX
-		rts
+		sta  P8ZP_SCRATCH_W1
+		sty  P8ZP_SCRATCH_W1+1
+		ldy  #0
+-		lda  (P8ZP_SCRATCH_W1),y
+		beq  +
+		jsr  c64.CHROUT
+		iny
+		bne  -
+		ldx  floats_store_reg
++		rts
 	}}
 }
 
-sub  print_fln  (float value) {
-	; ---- prints the floating point value (with a newline at the end) using basic rom routines
-	%asm {{
-		stx  c64.SCRATCH_ZPREGX
-		lda  #<value
-		ldy  #>value
-		jsr  MOVFM		; load float into fac1
-		jsr  FPRINTLN		; print fac1 with newline
-		ldx  c64.SCRATCH_ZPREGX
-		rts
-	}}
-
-}
-
 %asminclude "library:c64floats.asm", ""
 
-}  ; ------ end of block c64flt
+}

compiler/res/prog8lib/c64graphics.p8

@@ -0,0 +1,242 @@
+%target c64
+%import c64textio
+
+; bitmap pixel graphics module for the C64
+; only black/white monchrome for now
+; assumes bitmap screen memory is $2000-$3fff
+
+graphics {
+    const uword bitmap_address = $2000
+
+    sub enable_bitmap_mode() {
+        ; enable bitmap screen, erase it and set colors to black/white.
+        c64.SCROLY |= %00100000
+        c64.VMCSB = (c64.VMCSB & %11110000) | %00001000   ; $2000-$3fff
+        clear_screen(1, 0)
+    }
+
+    sub clear_screen(ubyte pixelcolor, ubyte bgcolor) {
+        memset(bitmap_address, 320*200/8, 0)
+        txt.fill_screen(pixelcolor << 4 | bgcolor, 0)
+    }
+
+    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 rewrite this in optimized assembly
+        if y1>y2 {
+            ; make sure dy is always positive to avoid 8 instead of just 4 special cases
+            swap(x1, x2)
+            swap(y1, y2)
+        }
+        word @zp d = 0
+        ubyte positive_ix = true
+        word @zp dx = x2 - x1 as word
+        word @zp dy = y2 as word - y1 as word
+        if dx < 0 {
+            dx = -dx
+            positive_ix = false
+        }
+        dx *= 2
+        dy *= 2
+        internal_plotx = x1
+
+        if dx >= dy {
+            if positive_ix {
+                repeat {
+                    internal_plot(y1)
+                    if internal_plotx==x2
+                        return
+                    internal_plotx++
+                    d += dy
+                    if d > dx {
+                        y1++
+                        d -= dx
+                    }
+                }
+            } else {
+                repeat {
+                    internal_plot(y1)
+                    if internal_plotx==x2
+                        return
+                    internal_plotx--
+                    d += dy
+                    if d > dx {
+                        y1++
+                        d -= dx
+                    }
+                }
+            }
+        }
+        else {
+            if positive_ix {
+                repeat {
+                    internal_plot(y1)
+                    if y1 == y2
+                        return
+                    y1++
+                    d += dx
+                    if d > dy {
+                        internal_plotx++
+                        d -= dy
+                    }
+                }
+            } else {
+                repeat {
+                    internal_plot(y1)
+                    if y1 == y2
+                        return
+                    y1++
+                    d += dx
+                    if d > dy {
+                        internal_plotx--
+                        d -= dy
+                    }
+                }
+            }
+        }
+    }
+
+    sub circle(uword xcenter, ubyte ycenter, ubyte radius) {
+        ; Midpoint algorithm
+        ubyte @zp ploty
+        ubyte @zp xx = radius
+        ubyte @zp yy = 0
+        byte @zp decisionOver2 = 1-xx as byte
+
+        while xx>=yy {
+            internal_plotx = xcenter + xx
+            ploty = ycenter + yy
+            internal_plot(ploty)
+            internal_plotx = xcenter - xx
+            internal_plot(ploty)
+            internal_plotx = xcenter + xx
+            ploty = ycenter - yy
+            internal_plot(ploty)
+            internal_plotx = xcenter - xx
+            internal_plot(ploty)
+            internal_plotx = xcenter + yy
+            ploty = ycenter + xx
+            internal_plot(ploty)
+            internal_plotx = xcenter - yy
+            internal_plot(ploty)
+            internal_plotx = xcenter + yy
+            ploty = ycenter - xx
+            internal_plot(ploty)
+            internal_plotx = xcenter - yy
+            internal_plot(ploty)
+            yy++
+            if decisionOver2<=0
+                decisionOver2 += 2*yy+1
+            else {
+                xx--
+                decisionOver2 += 2*(yy-xx)+1
+            }
+        }
+    }
+
+    sub disc(uword cx, ubyte cy, ubyte radius) {
+        ; Midpoint algorithm, filled
+        ubyte xx = radius
+        ubyte yy = 0
+        byte decisionOver2 = 1-xx as byte
+
+        while xx>=yy {
+            ubyte cy_plus_yy = cy + yy
+            ubyte cy_min_yy = cy - yy
+            ubyte cy_plus_xx = cy + xx
+            ubyte cy_min_xx = cy - xx
+
+            for internal_plotx in cx to cx+xx {
+                internal_plot(cy_plus_yy)
+                internal_plot(cy_min_yy)
+            }
+            for internal_plotx in cx-xx to cx-1 {
+                internal_plot(cy_plus_yy)
+                internal_plot(cy_min_yy)
+            }
+            for internal_plotx in cx to cx+yy {
+                internal_plot(cy_plus_xx)
+                internal_plot(cy_min_xx)
+            }
+            for internal_plotx in cx-yy to cx {
+                internal_plot(cy_plus_xx)
+                internal_plot(cy_min_xx)
+            }
+            yy++
+            if decisionOver2<=0
+                decisionOver2 += 2*yy+1
+            else {
+                xx--
+                decisionOver2 += 2*(yy-xx)+1
+            }
+        }
+    }
+
+
+; here is the non-asm code for the plot routine below:
+;    sub plot_nonasm(uword px, ubyte py) {
+;        ubyte[] ormask = [128, 64, 32, 16, 8, 4, 2, 1]
+;        uword addr = bitmap_address + 320*(py>>3) + (py & 7) + (px & %0000000111111000)
+;        @(addr) |= ormask[lsb(px) & 7]
+;    }
+
+    asmsub  plot(uword plotx @XY, ubyte ploty @A) clobbers (A, X, Y) {
+        %asm {{
+            stx  internal_plotx
+            sty  internal_plotx+1
+            jmp  internal_plot
+        }}
+    }
+
+    ; for efficiency of internal algorithms here is the internal plot routine
+    ; that takes the plotx coordinate in a separate variable instead of the XY register pair:
+
+    uword internal_plotx     ; 0..319        ; separate 'parameter' for internal_plot()
+
+    asmsub  internal_plot(ubyte ploty @A) clobbers (A, X, Y) {      ; internal_plotx is 16 bits 0 to 319... doesn't fit in a register
+        %asm {{
+        tay
+        lda  internal_plotx+1
+        sta  P8ZP_SCRATCH_W2+1
+        lsr  a            ; 0
+        sta  P8ZP_SCRATCH_W2
+        lda  internal_plotx
+        pha
+        and  #7
+        tax
+
+        lda  _y_lookup_lo,y
+        clc
+        adc  P8ZP_SCRATCH_W2
+        sta  P8ZP_SCRATCH_W2
+        lda  _y_lookup_hi,y
+        adc  P8ZP_SCRATCH_W2+1
+        sta  P8ZP_SCRATCH_W2+1
+
+        pla     ; internal_plotx
+        and  #%11111000
+        tay
+        lda  (P8ZP_SCRATCH_W2),y
+        ora  _ormask,x
+        sta  (P8ZP_SCRATCH_W2),y
+        rts
+
+_ormask     .byte 128, 64, 32, 16, 8, 4, 2, 1
+
+; note: this can be even faster if we also have a 256 byte x-lookup table, but hey.
+; see http://codebase64.org/doku.php?id=base:various_techniques_to_calculate_adresses_fast_common_screen_formats_for_pixel_graphics
+; the y lookup tables encodes this formula:  bitmap_address + 320*(py>>3) + (py & 7)    (y from 0..199)
+; We use the 64tass syntax for range expressions to calculate this table on assembly time.
+
+_plot_y_values := $2000 + 320*(range(200)>>3) + (range(200) & 7)
+
+_y_lookup_lo    .byte  <_plot_y_values
+_y_lookup_hi    .byte  >_plot_y_values
+
+        }}
+    }
+
+}
+
+

compiler/res/prog8lib/c64lib.p8

@@ -5,17 +5,9 @@
 ;
 ; indent format: TABS, size=8
 
+%target c64
 
 c64 {
-        const  uword  ESTACK_LO = $ce00     ; evaluation stack (lsb)
-        const  uword  ESTACK_HI = $cf00     ; evaluation stack (msb)
-        &ubyte  SCRATCH_ZPB1    = $02       ; scratch byte 1 in ZP
-        &ubyte  SCRATCH_ZPREG   = $03       ; scratch register in ZP
-        &ubyte  SCRATCH_ZPREGX  = $fa       ; temp storage for X register (stack pointer)
-        &uword  SCRATCH_ZPWORD1 = $fb       ; scratch word in ZP ($fb/$fc)
-        &uword  SCRATCH_ZPWORD2 = $fd       ; scratch word in ZP ($fd/$fe)
-
-
         &ubyte  TIME_HI         = $a0       ; software jiffy clock, hi byte
         &ubyte  TIME_MID        = $a1       ;  .. mid byte
         &ubyte  TIME_LO         = $a2       ;    .. lo byte. Updated by IRQ every 1/60 sec
@@ -183,19 +175,11 @@ c64 {
 ; ---- end of SID registers ----
 
 
-
-; ---- C64 basic routines ----
-
-romsub $E544 = CLEARSCR() clobbers(A,X,Y)       ; clear the screen
-romsub $E566 = HOMECRSR() clobbers(A,X,Y)       ; cursor to top left of screen
-
-
-; ---- end of C64 basic routines ----
-
-
-; ---- C64 kernal routines ----
+; ---- C64 ROM kernal routines ----
 
 romsub $AB1E = STROUT(uword strptr @ AY) clobbers(A, X, Y)      ; print null-terminated string (use c64scr.print instead)
+romsub $E544 = CLEARSCR() clobbers(A,X,Y)                       ; clear the screen
+romsub $E566 = HOMECRSR() clobbers(A,X,Y)                       ; cursor to top left of screen
 romsub $EA31 = IRQDFRT() clobbers(A,X,Y)                        ; default IRQ routine
 romsub $EA81 = IRQDFEND() clobbers(A,X,Y)                       ; default IRQ end/cleanup
 romsub $FF81 = CINT() clobbers(A,X,Y)                           ; (alias: SCINIT) initialize screen editor and video chip
@@ -238,6 +222,207 @@ romsub $FFED = SCREEN() -> ubyte @ X, ubyte @ Y                 ; read number of
 romsub $FFF0 = PLOT(ubyte col @ Y, ubyte row @ X, ubyte dir @ Pc) -> ubyte @ X, ubyte @ Y       ; read/set position of cursor on screen.  Use c64scr.plot for a 'safe' wrapper that preserves X.
 romsub $FFF3 = IOBASE() -> uword @ XY                           ; read base address of I/O devices
 
-; ---- end of C64 kernal routines ----
+; ---- end of C64 ROM kernal routines ----
+
+
+; ---- C64 specific system utility routines: ----
+
+asmsub  init_system()  {
+    ; Initializes the machine to a sane starting state.
+    ; Called automatically by the loader program logic.
+    ; This means that the BASIC, KERNAL and CHARGEN ROMs are banked in,
+    ; the VIC, SID and CIA chips are reset, screen is cleared, and the default IRQ is set.
+    ; Also a different color scheme is chosen to identify ourselves a little.
+    ; Uppercase charset is activated, and all three registers set to 0, status flags cleared.
+    %asm {{
+        sei
+        cld
+        lda  #%00101111
+        sta  $00
+        lda  #%00100111
+        sta  $01
+        jsr  c64.IOINIT
+        jsr  c64.RESTOR
+        jsr  c64.CINT
+        lda  #6
+        sta  c64.EXTCOL
+        lda  #7
+        sta  c64.COLOR
+        lda  #0
+        sta  c64.BGCOL0
+        tax
+        tay
+        clc
+        clv
+        cli
+        rts
+    }}
+}
+
+asmsub  set_irqvec_excl() clobbers(A)  {
+	%asm {{
+		sei
+		lda  #<_irq_handler
+		sta  c64.CINV
+		lda  #>_irq_handler
+		sta  c64.CINV+1
+		cli
+		rts
+_irq_handler	jsr  set_irqvec._irq_handler_init
+		jsr  irq.irq
+		jsr  set_irqvec._irq_handler_end
+		lda  #$ff
+		sta  c64.VICIRQ			; acknowledge raster irq
+		lda  c64.CIA1ICR		; acknowledge CIA1 interrupt
+		jmp  c64.IRQDFEND		; end irq processing - don't call kernel
+	}}
+}
+
+asmsub  set_irqvec() clobbers(A)  {
+	%asm {{
+		sei
+		lda  #<_irq_handler
+		sta  c64.CINV
+		lda  #>_irq_handler
+		sta  c64.CINV+1
+		cli
+		rts
+_irq_handler    jsr  _irq_handler_init
+		jsr  irq.irq
+		jsr  _irq_handler_end
+		jmp  c64.IRQDFRT		; continue with normal kernel irq routine
+
+_irq_handler_init
+		; save all zp scratch registers and the X register as these might be clobbered by the irq routine
+		stx  IRQ_X_REG
+		lda  P8ZP_SCRATCH_B1
+		sta  IRQ_SCRATCH_ZPB1
+		lda  P8ZP_SCRATCH_REG
+		sta  IRQ_SCRATCH_ZPREG
+		lda  P8ZP_SCRATCH_W1
+		sta  IRQ_SCRATCH_ZPWORD1
+		lda  P8ZP_SCRATCH_W1+1
+		sta  IRQ_SCRATCH_ZPWORD1+1
+		lda  P8ZP_SCRATCH_W2
+		sta  IRQ_SCRATCH_ZPWORD2
+		lda  P8ZP_SCRATCH_W2+1
+		sta  IRQ_SCRATCH_ZPWORD2+1
+		; stack protector; make sure we don't clobber the top of the evaluation stack
+		dex
+		dex
+		dex
+		dex
+		dex
+		dex
+		cld
+		rts
+
+_irq_handler_end
+		; restore all zp scratch registers and the X register
+		lda  IRQ_SCRATCH_ZPB1
+		sta  P8ZP_SCRATCH_B1
+		lda  IRQ_SCRATCH_ZPREG
+		sta  P8ZP_SCRATCH_REG
+		lda  IRQ_SCRATCH_ZPWORD1
+		sta  P8ZP_SCRATCH_W1
+		lda  IRQ_SCRATCH_ZPWORD1+1
+		sta  P8ZP_SCRATCH_W1+1
+		lda  IRQ_SCRATCH_ZPWORD2
+		sta  P8ZP_SCRATCH_W2
+		lda  IRQ_SCRATCH_ZPWORD2+1
+		sta  P8ZP_SCRATCH_W2+1
+		ldx  IRQ_X_REG
+		rts
+
+IRQ_X_REG		.byte  0
+IRQ_SCRATCH_ZPB1	.byte  0
+IRQ_SCRATCH_ZPREG	.byte  0
+IRQ_SCRATCH_ZPWORD1	.word  0
+IRQ_SCRATCH_ZPWORD2	.word  0
+
+		}}
+}
+
+asmsub  restore_irqvec() {
+	%asm {{
+		sei
+		lda  #<c64.IRQDFRT
+		sta  c64.CINV
+		lda  #>c64.IRQDFRT
+		sta  c64.CINV+1
+		lda  #0
+		sta  c64.IREQMASK	; disable raster irq
+		lda  #%10000001
+		sta  c64.CIA1ICR	; restore CIA1 irq
+		cli
+		rts
+	}}
+}
+
+asmsub  set_rasterirq(uword rasterpos @ AY) clobbers(A) {
+	%asm {{
+		sei
+		jsr  _setup_raster_irq
+		lda  #<_raster_irq_handler
+		sta  c64.CINV
+		lda  #>_raster_irq_handler
+		sta  c64.CINV+1
+		cli
+		rts
+
+_raster_irq_handler
+		jsr  set_irqvec._irq_handler_init
+		jsr  irq.irq
+		jsr  set_irqvec._irq_handler_end
+		lda  #$ff
+		sta  c64.VICIRQ			; acknowledge raster irq
+		jmp  c64.IRQDFRT
+
+_setup_raster_irq
+		pha
+		lda  #%01111111
+		sta  c64.CIA1ICR    ; "switch off" interrupts signals from cia-1
+		sta  c64.CIA2ICR    ; "switch off" interrupts signals from cia-2
+		and  c64.SCROLY
+		sta  c64.SCROLY     ; clear most significant bit of raster position
+		lda  c64.CIA1ICR    ; ack previous irq
+		lda  c64.CIA2ICR    ; ack previous irq
+		pla
+		sta  c64.RASTER     ; set the raster line number where interrupt should occur
+		cpy  #0
+		beq  +
+		lda  c64.SCROLY
+		ora  #%10000000
+		sta  c64.SCROLY     ; set most significant bit of raster position
++		lda  #%00000001
+		sta  c64.IREQMASK   ;enable raster interrupt signals from vic
+		rts
+	}}
+}
+
+asmsub  set_rasterirq_excl(uword rasterpos @ AY) clobbers(A) {
+	%asm {{
+		sei
+		jsr  set_rasterirq._setup_raster_irq
+		lda  #<_raster_irq_handler
+		sta  c64.CINV
+		lda  #>_raster_irq_handler
+		sta  c64.CINV+1
+		cli
+		rts
+
+_raster_irq_handler
+		jsr  set_irqvec._irq_handler_init
+		jsr  irq.irq
+		jsr  set_irqvec._irq_handler_end
+		lda  #$ff
+		sta  c64.VICIRQ			; acknowledge raster irq
+		jmp  c64.IRQDFEND		; end irq processing - don't call kernel
+
+	}}
+}
+
+; ---- end of C64 specific system utility routines ----
+
 
 }

compiler/res/prog8lib/c64textio.p8

@@ -0,0 +1,556 @@
+; Prog8 definitions for the Text I/O and Screen routines for the Commodore-64
+;
+; Written by Irmen de Jong (irmen@razorvine.net) - license: GNU GPL 3.0
+;
+; indent format: TABS, size=8
+
+
+%target c64
+%import c64lib
+%import conv
+
+
+txt {
+
+asmsub  clear_screen() {
+    %asm {{
+        lda  #' '
+        jmp  clear_screenchars
+    }}
+}
+
+
+asmsub  fill_screen (ubyte char @ A, ubyte charcolor @ Y) clobbers(A)  {
+	; ---- fill the character screen with the given fill character and character color.
+	;      (assumes screen and color matrix are at their default addresses)
+
+	%asm {{
+		pha
+		tya
+		jsr  clear_screencolors
+		pla
+		jsr  clear_screenchars
+		rts
+        }}
+
+}
+
+asmsub  clear_screenchars (ubyte char @ A) clobbers(Y)  {
+	; ---- clear the character screen with the given fill character (leaves colors)
+	;      (assumes screen matrix is at the default address)
+	%asm {{
+		ldy  #0
+_loop		sta  c64.Screen,y
+		sta  c64.Screen+$0100,y
+		sta  c64.Screen+$0200,y
+		sta  c64.Screen+$02e8,y
+		iny
+		bne  _loop
+		rts
+        }}
+}
+
+asmsub  clear_screencolors (ubyte scrcolor @ A) clobbers(Y)  {
+	; ---- clear the character screen colors with the given color (leaves characters).
+	;      (assumes color matrix is at the default address)
+	%asm {{
+		ldy  #0
+_loop		sta  c64.Colors,y
+		sta  c64.Colors+$0100,y
+		sta  c64.Colors+$0200,y
+		sta  c64.Colors+$02e8,y
+		iny
+		bne  _loop
+		rts
+        }}
+}
+
+sub color (ubyte txtcol) {
+    c64.COLOR = txtcol
+}
+
+asmsub  scroll_left_full  (ubyte alsocolors @ Pc) clobbers(A, Y)  {
+	; ---- scroll the whole screen 1 character to the left
+	;      contents of the rightmost column are unchanged, you should clear/refill this yourself
+	;      Carry flag determines if screen color data must be scrolled too
+
+	%asm {{
+		stx  P8ZP_SCRATCH_REG
+		bcs  +
+		jmp  _scroll_screen
+
++               ; scroll the color memory
+		ldx  #0
+		ldy  #38
+-
+	.for row=0, row<=24, row+=1
+		lda  c64.Colors + 40*row + 1,x
+		sta  c64.Colors + 40*row,x
+	.next
+		inx
+		dey
+		bpl  -
+
+_scroll_screen  ; scroll the screen memory
+		ldx  #0
+		ldy  #38
+-
+	.for row=0, row<=24, row+=1
+		lda  c64.Screen + 40*row + 1,x
+		sta  c64.Screen + 40*row,x
+	.next
+		inx
+		dey
+		bpl  -
+
+		ldx  P8ZP_SCRATCH_REG
+		rts
+	}}
+}
+
+asmsub  scroll_right_full  (ubyte alsocolors @ Pc) clobbers(A)  {
+	; ---- scroll the whole screen 1 character to the right
+	;      contents of the leftmost column are unchanged, you should clear/refill this yourself
+	;      Carry flag determines if screen color data must be scrolled too
+	%asm {{
+		stx  P8ZP_SCRATCH_REG
+		bcs  +
+		jmp  _scroll_screen
+
++               ; scroll the color memory
+		ldx  #38
+-
+	.for row=0, row<=24, row+=1
+		lda  c64.Colors + 40*row + 0,x
+		sta  c64.Colors + 40*row + 1,x
+	.next
+		dex
+		bpl  -
+
+_scroll_screen  ; scroll the screen memory
+		ldx  #38
+-
+	.for row=0, row<=24, row+=1
+		lda  c64.Screen + 40*row + 0,x
+		sta  c64.Screen + 40*row + 1,x
+	.next
+		dex
+		bpl  -
+
+		ldx  P8ZP_SCRATCH_REG
+		rts
+	}}
+}
+
+asmsub  scroll_up_full  (ubyte alsocolors @ Pc) clobbers(A)  {
+	; ---- scroll the whole screen 1 character up
+	;      contents of the bottom row are unchanged, you should refill/clear this yourself
+	;      Carry flag determines if screen color data must be scrolled too
+	%asm {{
+		stx  P8ZP_SCRATCH_REG
+		bcs  +
+		jmp  _scroll_screen
+
++               ; scroll the color memory
+		ldx #39
+-
+	.for row=1, row<=24, row+=1
+		lda  c64.Colors + 40*row,x
+		sta  c64.Colors + 40*(row-1),x
+	.next
+		dex
+		bpl  -
+
+_scroll_screen  ; scroll the screen memory
+		ldx #39
+-
+	.for row=1, row<=24, row+=1
+		lda  c64.Screen + 40*row,x
+		sta  c64.Screen + 40*(row-1),x
+	.next
+		dex
+		bpl  -
+
+		ldx  P8ZP_SCRATCH_REG
+		rts
+	}}
+}
+
+asmsub  scroll_down_full  (ubyte alsocolors @ Pc) clobbers(A)  {
+	; ---- scroll the whole screen 1 character down
+	;      contents of the top row are unchanged, you should refill/clear this yourself
+	;      Carry flag determines if screen color data must be scrolled too
+	%asm {{
+		stx  P8ZP_SCRATCH_REG
+		bcs  +
+		jmp  _scroll_screen
+
++               ; scroll the color memory
+		ldx #39
+-
+	.for row=23, row>=0, row-=1
+		lda  c64.Colors + 40*row,x
+		sta  c64.Colors + 40*(row+1),x
+	.next
+		dex
+		bpl  -
+
+_scroll_screen  ; scroll the screen memory
+		ldx #39
+-
+	.for row=23, row>=0, row-=1
+		lda  c64.Screen + 40*row,x
+		sta  c64.Screen + 40*(row+1),x
+	.next
+		dex
+		bpl  -
+
+		ldx  P8ZP_SCRATCH_REG
+		rts
+	}}
+}
+
+asmsub  print (str text @ AY) clobbers(A,Y)  {
+	; ---- print null terminated string from A/Y
+	; note: the compiler contains an optimization that will replace
+	;       a call to this subroutine with a string argument of just one char,
+	;       by just one call to c64.CHROUT of that single char.
+	%asm {{
+		sta  P8ZP_SCRATCH_B1
+		sty  P8ZP_SCRATCH_REG
+		ldy  #0
+-		lda  (P8ZP_SCRATCH_B1),y
+		beq  +
+		jsr  c64.CHROUT
+		iny
+		bne  -
++		rts
+	}}
+}
+
+asmsub  print_ub0  (ubyte value @ A) clobbers(A,Y)  {
+	; ---- print the ubyte in A in decimal form, with left padding 0s (3 positions total)
+	%asm {{
+		stx  P8ZP_SCRATCH_REG
+		jsr  conv.ubyte2decimal
+		pha
+		tya
+		jsr  c64.CHROUT
+		pla
+		jsr  c64.CHROUT
+		txa
+		jsr  c64.CHROUT
+		ldx  P8ZP_SCRATCH_REG
+		rts
+	}}
+}
+
+asmsub  print_ub  (ubyte value @ A) clobbers(A,Y)  {
+	; ---- print the ubyte in A in decimal form, without left padding 0s
+	%asm {{
+		stx  P8ZP_SCRATCH_REG
+		jsr  conv.ubyte2decimal
+_print_byte_digits
+		pha
+		cpy  #'0'
+		beq  +
+		tya
+		jsr  c64.CHROUT
+		pla
+		jsr  c64.CHROUT
+		jmp  _ones
++       pla
+        cmp  #'0'
+        beq  _ones
+        jsr  c64.CHROUT
+_ones   txa
+		jsr  c64.CHROUT
+		ldx  P8ZP_SCRATCH_REG
+		rts
+	}}
+}
+
+asmsub  print_b  (byte value @ A) clobbers(A,Y)  {
+	; ---- print the byte in A in decimal form, without left padding 0s
+	%asm {{
+		stx  P8ZP_SCRATCH_REG
+		pha
+		cmp  #0
+		bpl  +
+		lda  #'-'
+		jsr  c64.CHROUT
++		pla
+		jsr  conv.byte2decimal
+		jmp  print_ub._print_byte_digits
+	}}
+}
+
+asmsub  print_ubhex  (ubyte value @ A, ubyte prefix @ Pc) clobbers(A,Y)  {
+	; ---- print the ubyte in A in hex form (if Carry is set, a radix prefix '$' is printed as well)
+	%asm {{
+		stx  P8ZP_SCRATCH_REG
+		bcc  +
+		pha
+		lda  #'$'
+		jsr  c64.CHROUT
+		pla
++		jsr  conv.ubyte2hex
+		jsr  c64.CHROUT
+		tya
+		jsr  c64.CHROUT
+		ldx  P8ZP_SCRATCH_REG
+		rts
+	}}
+}
+
+asmsub  print_ubbin  (ubyte value @ A, ubyte prefix @ Pc) clobbers(A,Y)  {
+	; ---- print the ubyte in A in binary form (if Carry is set, a radix prefix '%' is printed as well)
+	%asm {{
+		stx  P8ZP_SCRATCH_REG
+		sta  P8ZP_SCRATCH_B1
+		bcc  +
+		lda  #'%'
+		jsr  c64.CHROUT
++		ldy  #8
+-		lda  #'0'
+		asl  P8ZP_SCRATCH_B1
+		bcc  +
+		lda  #'1'
++		jsr  c64.CHROUT
+		dey
+		bne  -
+		ldx  P8ZP_SCRATCH_REG
+		rts
+	}}
+}
+
+asmsub  print_uwbin  (uword value @ AY, ubyte prefix @ Pc) clobbers(A,Y)  {
+	; ---- print the uword in A/Y in binary form (if Carry is set, a radix prefix '%' is printed as well)
+	%asm {{
+		pha
+		tya
+		jsr  print_ubbin
+		pla
+		clc
+		jmp  print_ubbin
+	}}
+}
+
+asmsub  print_uwhex  (uword value @ AY, ubyte prefix @ Pc) clobbers(A,Y)  {
+	; ---- print the uword in A/Y in hexadecimal form (4 digits)
+	;      (if Carry is set, a radix prefix '$' is printed as well)
+	%asm {{
+		pha
+		tya
+		jsr  print_ubhex
+		pla
+		clc
+		jmp  print_ubhex
+	}}
+}
+
+asmsub  print_uw0  (uword value @ AY) clobbers(A,Y)  {
+	; ---- print the uword in A/Y in decimal form, with left padding 0s (5 positions total)
+	%asm {{
+	    stx  P8ZP_SCRATCH_REG
+		jsr  conv.uword2decimal
+		ldy  #0
+-		lda  conv.uword2decimal.decTenThousands,y
+        beq  +
+		jsr  c64.CHROUT
+		iny
+		bne  -
++		ldx  P8ZP_SCRATCH_REG
+		rts
+	}}
+}
+
+asmsub  print_uw  (uword value @ AY) clobbers(A,Y)  {
+	; ---- print the uword in A/Y in decimal form, without left padding 0s
+	%asm {{
+	    stx  P8ZP_SCRATCH_REG
+		jsr  conv.uword2decimal
+		ldx  P8ZP_SCRATCH_REG
+		ldy  #0
+-		lda  conv.uword2decimal.decTenThousands,y
+		beq  _allzero
+		cmp  #'0'
+		bne  _gotdigit
+		iny
+		bne  -
+
+_gotdigit
+		jsr  c64.CHROUT
+		iny
+		lda  conv.uword2decimal.decTenThousands,y
+		bne  _gotdigit
+		rts
+_allzero
+        lda  #'0'
+        jmp  c64.CHROUT
+	}}
+}
+
+asmsub  print_w  (word value @ AY) clobbers(A,Y)  {
+	; ---- print the (signed) word in A/Y in decimal form, without left padding 0's
+	%asm {{
+		cpy  #0
+		bpl  +
+		pha
+		lda  #'-'
+		jsr  c64.CHROUT
+		tya
+		eor  #255
+		tay
+		pla
+		eor  #255
+		clc
+		adc  #1
+		bcc  +
+		iny
++		jmp  print_uw
+	}}
+}
+
+asmsub  input_chars  (uword buffer @ AY) clobbers(A) -> ubyte @ Y  {
+	; ---- Input a string (max. 80 chars) from the keyboard. Returns length in Y. (string is terminated with a 0 byte as well)
+	;      It assumes the keyboard is selected as I/O channel!
+
+	%asm {{
+		sta  P8ZP_SCRATCH_W1
+		sty  P8ZP_SCRATCH_W1+1
+		ldy  #0				; char counter = 0
+-		jsr  c64.CHRIN
+		cmp  #$0d			; return (ascii 13) pressed?
+		beq  +				; yes, end.
+		sta  (P8ZP_SCRATCH_W1),y	; else store char in buffer
+		iny
+		bne  -
++		lda  #0
+		sta  (P8ZP_SCRATCH_W1),y	; finish string with 0 byte
+		rts
+
+	}}
+}
+
+asmsub  setchr  (ubyte col @Y, ubyte row @A) clobbers(A)  {
+	; ---- set the character in SCRATCH_ZPB1 on the screen matrix at the given position
+	%asm {{
+		sty  P8ZP_SCRATCH_REG
+		asl  a
+		tay
+		lda  _screenrows+1,y
+		sta  _mod+2
+		lda  _screenrows,y
+		clc
+		adc  P8ZP_SCRATCH_REG
+		sta  _mod+1
+		bcc  +
+		inc  _mod+2
++		lda  P8ZP_SCRATCH_B1
+_mod		sta  $ffff		; modified
+		rts
+
+_screenrows	.word  $0400 + range(0, 1000, 40)
+	}}
+}
+
+asmsub  getchr  (ubyte col @Y, ubyte row @A) clobbers(Y) -> ubyte @ A {
+	; ---- get the character in the screen matrix at the given location
+	%asm  {{
+		sty  P8ZP_SCRATCH_B1
+		asl  a
+		tay
+		lda  setchr._screenrows+1,y
+		sta  _mod+2
+		lda  setchr._screenrows,y
+		clc
+		adc  P8ZP_SCRATCH_B1
+		sta  _mod+1
+		bcc  _mod
+		inc  _mod+2
+_mod		lda  $ffff		; modified
+		rts
+	}}
+}
+
+asmsub  setclr  (ubyte col @Y, ubyte row @A) clobbers(A)  {
+	; ---- set the color in SCRATCH_ZPB1 on the screen matrix at the given position
+	%asm {{
+		sty  P8ZP_SCRATCH_REG
+		asl  a
+		tay
+		lda  _colorrows+1,y
+		sta  _mod+2
+		lda  _colorrows,y
+		clc
+		adc  P8ZP_SCRATCH_REG
+		sta  _mod+1
+		bcc  +
+		inc  _mod+2
++		lda  P8ZP_SCRATCH_B1
+_mod		sta  $ffff		; modified
+		rts
+
+_colorrows	.word  $d800 + range(0, 1000, 40)
+	}}
+}
+
+asmsub  getclr  (ubyte col @Y, ubyte row @A) clobbers(Y) -> ubyte @ A {
+	; ---- get the color in the screen color matrix at the given location
+	%asm  {{
+		sty  P8ZP_SCRATCH_B1
+		asl  a
+		tay
+		lda  setclr._colorrows+1,y
+		sta  _mod+2
+		lda  setclr._colorrows,y
+		clc
+		adc  P8ZP_SCRATCH_B1
+		sta  _mod+1
+		bcc  _mod
+		inc  _mod+2
+_mod		lda  $ffff		; modified
+		rts
+	}}
+}
+
+sub  setcc  (ubyte column, ubyte row, ubyte char, ubyte charcolor)  {
+	; ---- set char+color at the given position on the screen
+	%asm {{
+		lda  row
+		asl  a
+		tay
+		lda  setchr._screenrows+1,y
+		sta  _charmod+2
+		adc  #$d4
+		sta  _colormod+2
+		lda  setchr._screenrows,y
+		clc
+		adc  column
+		sta  _charmod+1
+		sta  _colormod+1
+		bcc  +
+		inc  _charmod+2
+		inc  _colormod+2
++		lda  char
+_charmod	sta  $ffff		; modified
+		lda  charcolor
+_colormod	sta  $ffff		; modified
+		rts
+	}}
+}
+
+asmsub  plot  (ubyte col @ Y, ubyte row @ A) clobbers(A) {
+	; ---- safe wrapper around PLOT kernel routine, to save the X register.
+	%asm  {{
+		stx  P8ZP_SCRATCH_REG
+		tax
+		clc
+		jsr  c64.PLOT
+		ldx  P8ZP_SCRATCH_REG
+		rts
+	}}
+}
+
+}

compiler/res/prog8lib/conv.p8

@@ -0,0 +1,361 @@
+; Prog8 definitions for number conversions routines.
+;
+; Written by Irmen de Jong (irmen@razorvine.net) - license: GNU GPL 3.0
+;
+; indent format: TABS, size=8
+
+
+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)
+    %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
+
+    }}
+}
+
+
+; ----- utility functions ----
+
+
+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)
+	}}
+}
+
+asmsub str2uword(str string @ AY) -> uword @ AY {
+	; -- returns the unsigned word value of the string number argument in AY
+	;    the number may NOT be preceded by a + sign and may NOT contain spaces
+	;    (any non-digit character will terminate the number string that is parsed)
+	%asm {{
+_result = P8ZP_SCRATCH_W2
+		sta  _mod+1
+		sty  _mod+2
+		ldy  #0
+		sty  _result
+		sty  _result+1
+_mod		lda  $ffff,y		; modified
+		sec
+		sbc  #48
+		bpl  +
+_done		; return result
+		lda  _result
+		ldy  _result+1
+		rts
++		cmp  #10
+		bcs  _done
+		; add digit to result
+		pha
+		jsr  _result_times_10
+		pla
+		clc
+		adc  _result
+		sta  _result
+		bcc  +
+		inc  _result+1
++		iny
+		bne  _mod
+		; never reached
+
+_result_times_10     ; (W*4 + W)*2
+		lda  _result+1
+		sta  P8ZP_SCRATCH_REG
+		lda  _result
+		asl  a
+		rol  P8ZP_SCRATCH_REG
+		asl  a
+		rol  P8ZP_SCRATCH_REG
+		clc
+		adc  _result
+		sta  _result
+		lda  P8ZP_SCRATCH_REG
+		adc  _result+1
+		asl  _result
+		rol  a
+		sta  _result+1
+		rts
+	}}
+}
+
+asmsub str2word(str string @ AY) -> word @ AY {
+	; -- returns the signed word value of the string number argument in AY
+	;    the number may be preceded by a + or - sign but may NOT contain spaces
+	;    (any non-digit character will terminate the number string that is parsed)
+	%asm {{
+_result = P8ZP_SCRATCH_W2
+		sta  P8ZP_SCRATCH_W1
+		sty  P8ZP_SCRATCH_W1+1
+		ldy  #0
+		sty  _result
+		sty  _result+1
+		sty  _negative
+		lda  (P8ZP_SCRATCH_W1),y
+		cmp  #'+'
+		bne  +
+		iny
++		cmp  #'-'
+		bne  _parse
+		inc  _negative
+		iny
+_parse		lda  (P8ZP_SCRATCH_W1),y
+		sec
+		sbc  #48
+		bpl  _digit
+_done		; return result
+		lda  _negative
+		beq  +
+		sec
+		lda  #0
+		sbc  _result
+		sta  _result
+		lda  #0
+		sbc  _result+1
+		sta  _result+1
++		lda  _result
+		ldy  _result+1
+		rts
+_digit		cmp  #10
+		bcs  _done
+		; add digit to result
+		pha
+		jsr  str2uword._result_times_10
+		pla
+		clc
+		adc  _result
+		sta  _result
+		bcc  +
+		inc  _result+1
++		iny
+		bne  _parse
+		; never reached
+_negative	.byte  0
+	}}
+}
+
+}

compiler/res/prog8lib/cx16flt.p8

@@ -0,0 +1,153 @@
+; Prog8 definitions for floating point handling on the CommanderX16
+;
+; Written by Irmen de Jong (irmen@razorvine.net) - license: GNU GPL 3.0
+;
+; indent format: TABS, size=8
+
+%target cx16
+%option enable_floats
+
+c64flt {
+	; ---- this block contains C-64 floating point related functions ----
+
+        const float  PI     = 3.141592653589793
+        const float  TWOPI  = 6.283185307179586
+
+
+; ---- ROM float functions ----
+
+		; note: the fac1 and fac2 are working registers and take 6 bytes each,
+		; floats in memory  (and rom) are stored in 5-byte MFLPT packed format.
+
+; note: fac1/2 might get clobbered even if not mentioned in the function's name.
+; note: for subtraction and division, the left operand is in fac2, the right operand in fac1.
+
+romsub $fe00 = AYINT() clobbers(A,X,Y)          ; fac1-> signed word in 100-101 ($64-$65) MSB FIRST. (might throw ILLEGAL QUANTITY)
+
+; GIVAYF: signed word in Y/A (note different lsb/msb order) -> float in fac1
+; there is also c64flt.GIVUAYFAY - unsigned word in A/Y (lo/hi) to fac1
+; (tip: use GIVAYFAY to use A/Y input; lo/hi switched to normal order)
+romsub $fe03 = GIVAYF(ubyte lo @ Y, ubyte hi @ A) clobbers(A,X,Y)
+
+; fac1 -> unsigned word in Y/A (might throw ILLEGAL QUANTITY) (result also in $14/15)
+; (tip: use GETADRAY to get A/Y output; lo/hi switched to normal little endian order)
+romsub $fe06 = GETADR() clobbers(X) -> ubyte @ Y, ubyte @ A
+
+romsub $fe09 = FADDH() clobbers(A,X,Y)                      ; fac1 += 0.5, for rounding- call this before INT
+romsub $fe0c = FSUB(uword mflpt @ AY) clobbers(A,X,Y)       ; fac1 = mflpt from A/Y - fac1
+romsub $fe0f = FSUBT() clobbers(A,X,Y)                      ; fac1 = fac2-fac1   mind the order of the operands
+romsub $fe12 = FADD(uword mflpt @ AY) clobbers(A,X,Y)       ; fac1 += mflpt value from A/Y
+romsub $fe15 = FADDT() clobbers(A,X,Y)                      ; fac1 += fac2
+romsub $fe1b = ZEROFC() clobbers(A,X,Y)                     ; fac1 = 0
+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 $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
+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)
+
+
+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_REG
+        sty  P8ZP_SCRATCH_B1
+        tya
+        ldy  P8ZP_SCRATCH_REG
+        jsr  GIVAYF                 ; load it as signed... correct afterwards
+        lda  P8ZP_SCRATCH_B1
+	    bpl  +
+	    lda  #<_flt65536
+	    ldy  #>_flt65536
+	    jsr  FADD
++	    plx
+        rts
+_flt65536    .byte 145,0,0,0,0       ; 65536.0
+	}}
+}
+
+
+asmsub  GIVAYFAY  (uword value @ AY) clobbers(A,X,Y)  {
+	; ---- signed 16 bit word in A/Y (lo/hi) to float in fac1
+	%asm {{
+		sta  P8ZP_SCRATCH_REG
+		tya
+		ldy  P8ZP_SCRATCH_REG
+		jmp  GIVAYF		; this uses the inverse order, Y/A
+	}}
+}
+
+asmsub  FTOSWRDAY  () clobbers(X) -> uword @ AY  {
+	; ---- fac1 to signed word in A/Y
+	%asm {{
+		jsr  FTOSWORDYA	; note the inverse Y/A order
+		sta  P8ZP_SCRATCH_REG
+		tya
+		ldy  P8ZP_SCRATCH_REG
+		rts
+	}}
+}
+
+asmsub  GETADRAY  () clobbers(X) -> uword @ AY  {
+	; ---- fac1 to unsigned word in A/Y
+	%asm {{
+		jsr  GETADR		; this uses the inverse order, Y/A
+		sta  P8ZP_SCRATCH_B1
+		tya
+		ldy  P8ZP_SCRATCH_B1
+		rts
+	}}
+}
+
+sub  print_f  (float value) {
+	; ---- prints the floating point value (without a newline).
+	%asm {{
+		phx
+		lda  #<value
+		ldy  #>value
+		jsr  MOVFM		; load float into fac1
+		jsr  FOUT		; fac1 to string in A/Y
+		sta  P8ZP_SCRATCH_W1
+		sty  P8ZP_SCRATCH_W1+1
+		ldy  #0
+-		lda  (P8ZP_SCRATCH_W1),y
+		beq  +
+		jsr  c64.CHROUT
+		iny
+		bne  -
+		plx
++		rts
+	}}
+}
+
+%asminclude "library:c64floats.asm", ""
+
+}

compiler/res/prog8lib/cx16lib.p8

@@ -0,0 +1,272 @@
+; Prog8 definitions for the CommanderX16
+; Including memory registers, I/O registers, Basic and Kernal subroutines.
+;
+; Written by Irmen de Jong (irmen@razorvine.net) - license: GNU GPL 3.0
+;
+; indent format: TABS, size=8
+
+%target cx16
+
+
+c64 {
+
+; ---- kernal routines, these are the same as on the Commodore-64 (hence the same block name) ----
+
+; STROUT --> use screen.print
+; CLEARSCR -> use screen.clear_screen
+; HOMECRSR -> use screen.plot
+
+romsub $FF81 = CINT()  clobbers(A,X,Y)                           ; (alias: SCINIT) initialize screen editor and video chip
+romsub $FF84 = IOINIT()  clobbers(A, X)                          ; initialize I/O devices (CIA, SID, IRQ)
+romsub $FF87 = RAMTAS()  clobbers(A,X,Y)                         ; initialize RAM, tape buffer, screen
+romsub $FF8A = RESTOR()  clobbers(A,X,Y)                         ; restore default I/O vectors
+romsub $FF8D = VECTOR(uword userptr @ XY, ubyte dir @ Pc)  clobbers(A,Y)     ; read/set I/O vector table
+romsub $FF90 = SETMSG(ubyte value @ A)                          ; set Kernal message control flag
+romsub $FF93 = SECOND(ubyte address @ A)  clobbers(A)            ; (alias: LSTNSA) send secondary address after LISTEN
+romsub $FF96 = TKSA(ubyte address @ A)  clobbers(A)              ; (alias: TALKSA) send secondary address after TALK
+romsub $FF99 = MEMTOP(uword address @ XY, ubyte dir @ Pc) -> uword @ XY     ; read/set top of memory  pointer
+romsub $FF9C = MEMBOT(uword address @ XY, ubyte dir @ Pc) -> uword @ XY     ; read/set bottom of memory  pointer
+romsub $FF9F = SCNKEY()  clobbers(A,X,Y)                         ; scan the keyboard
+romsub $FFA2 = SETTMO(ubyte timeout @ A)                        ; set time-out flag for IEEE bus
+romsub $FFA5 = ACPTR() -> ubyte @ A                             ; (alias: IECIN) input byte from serial bus
+romsub $FFA8 = CIOUT(ubyte databyte @ A)                        ; (alias: IECOUT) output byte to serial bus
+romsub $FFAB = UNTLK()  clobbers(A)                              ; command serial bus device to UNTALK
+romsub $FFAE = UNLSN()  clobbers(A)                              ; command serial bus device to UNLISTEN
+romsub $FFB1 = LISTEN(ubyte device @ A)  clobbers(A)             ; command serial bus device to LISTEN
+romsub $FFB4 = TALK(ubyte device @ A)  clobbers(A)               ; command serial bus device to TALK
+romsub $FFB7 = READST() -> ubyte @ A                            ; read I/O status word
+romsub $FFBA = SETLFS(ubyte logical @ A, ubyte device @ X, ubyte address @ Y)   ; set logical file parameters
+romsub $FFBD = SETNAM(ubyte namelen @ A, str filename @ XY)     ; set filename parameters
+romsub $FFC0 = OPEN()  clobbers(A,X,Y)                           ; (via 794 ($31A)) open a logical file
+romsub $FFC3 = CLOSE(ubyte logical @ A)  clobbers(A,X,Y)         ; (via 796 ($31C)) close a logical file
+romsub $FFC6 = CHKIN(ubyte logical @ X)  clobbers(A,X)           ; (via 798 ($31E)) define an input channel
+romsub $FFC9 = CHKOUT(ubyte logical @ X)  clobbers(A,X)          ; (via 800 ($320)) define an output channel
+romsub $FFCC = CLRCHN()  clobbers(A,X)                           ; (via 802 ($322)) restore default devices
+romsub $FFCF = CHRIN()  clobbers(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 $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 $FFE1 = STOP()  clobbers(A,X) -> ubyte @ Pz, ubyte @ Pc   ; (via 808 ($328)) check the STOP key
+romsub $FFE4 = GETIN()  clobbers(X,Y) -> ubyte @ A               ; (via 810 ($32A)) get a character
+romsub $FFE7 = CLALL()  clobbers(A,X)                            ; (via 812 ($32C)) close all files
+romsub $FFEA = UDTIM()  clobbers(A,X)                            ; update the software clock
+romsub $FFED = SCREEN() -> ubyte @ X, ubyte @ Y                 ; read number of screen rows and columns
+romsub $FFF0 = PLOT(ubyte col @ Y, ubyte row @ X, ubyte dir @ Pc) -> ubyte @ X, ubyte @ Y       ; read/set position of cursor on screen.  Use screen.plot for a 'safe' wrapper that preserves X.
+romsub $FFF3 = IOBASE() -> uword @ XY                           ; read base address of I/O devices
+
+}
+
+cx16 {
+
+        ; 65c02 hardware vectors:
+        &uword  NMI_VEC         = $FFFA     ; 6502 nmi vector, determined by the kernal if banked in
+        &uword  RESET_VEC       = $FFFC     ; 6502 reset vector, determined by the kernal if banked in
+        &uword  IRQ_VEC         = $FFFE     ; 6502 interrupt vector, determined by the kernal if banked in
+
+
+; the sixteen virtual 16-bit registers
+    &uword r0  = $02
+    &uword r1  = $04
+    &uword r2  = $06
+    &uword r3  = $08
+    &uword r4  = $0a
+    &uword r5  = $0c
+    &uword r6  = $0e
+    &uword r7  = $10
+    &uword r8  = $12
+    &uword r9  = $14
+    &uword r10 = $16
+    &uword r11 = $18
+    &uword r12 = $1a
+    &uword r13 = $1c
+    &uword r14 = $1e
+    &uword r15 = $20
+
+; VERA registers
+
+    const uword VERA_BASE = $9F20
+    &ubyte  VERA_ADDR_L   	  = VERA_BASE + $00
+    &ubyte  VERA_ADDR_M   	  = VERA_BASE + $01
+    &ubyte  VERA_ADDR_H   	  = VERA_BASE + $02
+    &ubyte  VERA_DATA0        = VERA_BASE + $03
+    &ubyte  VERA_DATA1        = VERA_BASE + $04
+    &ubyte  VERA_CTRL         = VERA_BASE + $05
+    &ubyte  VERA_IEN          = VERA_BASE + $06
+    &ubyte  VERA_ISR          = VERA_BASE + $07
+    &ubyte  VERA_IRQ_LINE_L   = VERA_BASE + $08
+    &ubyte  VERA_DC_VIDEO     = VERA_BASE + $09
+    &ubyte  VERA_DC_HSCALE    = VERA_BASE + $0A
+    &ubyte  VERA_DC_VSCALE    = VERA_BASE + $0B
+    &ubyte  VERA_DC_BORDER    = VERA_BASE + $0C
+    &ubyte  VERA_DC_HSTART    = VERA_BASE + $09
+    &ubyte  VERA_DC_HSTOP     = VERA_BASE + $0A
+    &ubyte  VERA_DC_VSTART    = VERA_BASE + $0B
+    &ubyte  VERA_DC_VSTOP     = VERA_BASE + $0C
+    &ubyte  VERA_L0_CONFIG    = VERA_BASE + $0D
+    &ubyte  VERA_L0_MAPBASE   = VERA_BASE + $0E
+    &ubyte  VERA_L0_TILEBASE  = VERA_BASE + $0F
+    &ubyte  VERA_L0_HSCROLL_L = VERA_BASE + $10
+    &ubyte  VERA_L0_HSCROLL_H = VERA_BASE + $11
+    &ubyte  VERA_L0_VSCROLL_L = VERA_BASE + $12
+    &ubyte  VERA_L0_VSCROLL_H = VERA_BASE + $13
+    &ubyte  VERA_L1_CONFIG    = VERA_BASE + $14
+    &ubyte  VERA_L1_MAPBASE   = VERA_BASE + $15
+    &ubyte  VERA_L1_TILEBASE  = VERA_BASE + $16
+    &ubyte  VERA_L1_HSCROLL_L = VERA_BASE + $17
+    &ubyte  VERA_L1_HSCROLL_H = VERA_BASE + $18
+    &ubyte  VERA_L1_VSCROLL_L = VERA_BASE + $19
+    &ubyte  VERA_L1_VSCROLL_H = VERA_BASE + $1A
+    &ubyte  VERA_AUDIO_CTRL   = VERA_BASE + $1B
+    &ubyte  VERA_AUDIO_RATE   = VERA_BASE + $1C
+    &ubyte  VERA_AUDIO_DATA   = VERA_BASE + $1D
+    &ubyte  VERA_SPI_DATA     = VERA_BASE + $1E
+    &ubyte  VERA_SPI_CTRL     = VERA_BASE + $1F
+; VERA_PSG_BASE     = $1F9C0
+; VERA_PALETTE_BASE = $1FA00
+; VERA_SPRITES_BASE = $1FC00
+
+; I/O
+
+    const uword  via1  = $9f60                  ;VIA 6522 #1
+    &ubyte  d1prb	= via1+0
+    &ubyte  d1pra	= via1+1
+    &ubyte  d1ddrb	= via1+2
+    &ubyte  d1ddra	= via1+3
+    &ubyte  d1t1l	= via1+4
+    &ubyte  d1t1h	= via1+5
+    &ubyte  d1t1ll	= via1+6
+    &ubyte  d1t1lh	= via1+7
+    &ubyte  d1t2l	= via1+8
+    &ubyte  d1t2h	= via1+9
+    &ubyte  d1sr	= via1+10
+    &ubyte  d1acr	= via1+11
+    &ubyte  d1pcr	= via1+12
+    &ubyte  d1ifr	= via1+13
+    &ubyte  d1ier	= via1+14
+    &ubyte  d1ora	= via1+15
+
+    const uword  via2  = $9f70                  ;VIA 6522 #2
+    &ubyte  d2prb	=via2+0
+    &ubyte  d2pra	=via2+1
+    &ubyte  d2ddrb	=via2+2
+    &ubyte  d2ddra	=via2+3
+    &ubyte  d2t1l	=via2+4
+    &ubyte  d2t1h	=via2+5
+    &ubyte  d2t1ll	=via2+6
+    &ubyte  d2t1lh	=via2+7
+    &ubyte  d2t2l	=via2+8
+    &ubyte  d2t2h	=via2+9
+    &ubyte  d2sr	=via2+10
+    &ubyte  d2acr	=via2+11
+    &ubyte  d2pcr	=via2+12
+    &ubyte  d2ifr	=via2+13
+    &ubyte  d2ier	=via2+14
+    &ubyte  d2ora	=via2+15
+
+
+; ---- Commander X-16 additions on top of C64 kernal routines ----
+; spelling of the names is taken from the Commander X-16 rom sources
+
+; TODO specify the correct clobbers for alle these functions, for simplicity all 3 regs are marked clobbered atm
+
+; supported C128 additions
+romsub $ff4a = close_all()  clobbers(A,X,Y)
+romsub $ff59 = lkupla()  clobbers(A,X,Y)
+romsub $ff5c = lkupsa()  clobbers(A,X,Y)
+romsub $ff5f = screen_set_mode(ubyte mode @A)  clobbers(A, X, Y) -> ubyte @Pc
+romsub $ff62 = screen_set_charset(ubyte charset @A, uword charsetptr @XY)  clobbers(A,X,Y)      ; incompatible with C128  dlchr()
+romsub $ff65 = pfkey()  clobbers(A,X,Y)
+romsub $ff6e = jsrfar()  clobbers(A,X,Y)
+romsub $ff74 = fetch()  clobbers(A,X,Y)
+romsub $ff77 = stash()  clobbers(A,X,Y)
+romsub $ff7a = cmpare()  clobbers(A,X,Y)
+romsub $ff7d = primm()  clobbers(A,X,Y)
+
+; X16 additions
+romsub $ff44 = macptr()  clobbers(A,X,Y)
+romsub $ff47 = enter_basic(ubyte cold_or_warm @Pc)  clobbers(A,X,Y)
+romsub $ff68 = mouse_config(ubyte shape @A, ubyte scale @X)  clobbers (A, X, Y)
+romsub $ff6b = mouse_get(ubyte zpdataptr @X)  clobbers(A)
+romsub $ff71 = mouse_scan()  clobbers(A, X, Y)
+romsub $ff53 = joystick_scan()  clobbers(A, X, Y)
+romsub $ff56 = joystick_get(ubyte joynr @A) -> ubyte @A, ubyte @X, ubyte @Y
+romsub $ff4d = clock_set_date_time()  clobbers(A, X, Y)      ; args: r0, r1, r2, r3L
+romsub $ff50 = clock_get_date_time()  clobbers(A)            ; outout args: r0, r1, r2, r3L
+
+; high level graphics & fonts
+romsub $ff20 = GRAPH_init()  clobbers(A,X,Y)           ; uses vectors=r0
+romsub $ff23 = GRAPH_clear()  clobbers(A,X,Y)
+romsub $ff26 = GRAPH_set_window()  clobbers(A,X,Y)      ; uses x=r0, y=r1, width=r2, height=r3
+romsub $ff29 = GRAPH_set_colors(ubyte stroke @A, ubyte fill @X, ubyte background @Y)  clobbers (A,X,Y)
+romsub $ff2c = GRAPH_draw_line()  clobbers(A,X,Y)       ; uses x1=r0, y1=r1, x2=r2, y2=r3
+romsub $ff2f = GRAPH_draw_rect(ubyte fill @Pc)  clobbers(A,X,Y)   ; uses x=r0, y=r1, width=r2, height=r3, cornerradius=r4
+romsub $ff32 = GRAPH_move_rect()  clobbers(A,X,Y)       ; uses sx=r0, sy=r1, tx=r2, ty=r3, width=r4, height=r5
+romsub $ff35 = GRAPH_draw_oval(ubyte fill @Pc)  clobbers(A,X,Y)       ; uses x=r0, y=r1, width=r2, height=r3
+romsub $ff38 = GRAPH_draw_image()  clobbers(A,X,Y)      ; uses x=r0, y=r1, ptr=r2, width=r3, height=r4
+romsub $ff3b = GRAPH_set_font()  clobbers(A,X,Y)         ; uses ptr=r0
+romsub $ff3e = GRAPH_get_char_size(ubyte baseline @A, ubyte width @X, ubyte height_or_style @Y, ubyte is_control @Pc)  clobbers(A,X,Y)
+romsub $ff41 = GRAPH_put_char(ubyte char @A)  clobbers(A,X,Y)   ; uses x=r0, y=r1
+
+; framebuffer
+romsub $fef6 = FB_init()  clobbers(A,X,Y)
+romsub $fef9 = FB_get_info()  clobbers(X,Y) -> byte @A    ; also outputs width=r0, height=r1
+romsub $fefc = FB_set_palette(ubyte index @A, ubyte bytecount @X)  clobbers(A,X,Y)      ; also uses pointer=r0
+romsub $feff = FB_cursor_position()  clobbers(A,X,Y)    ; uses x=r0, y=r1
+romsub $ff02 = FB_cursor_next_line()  clobbers(A,X,Y)   ; uses x=r0
+romsub $ff05 = FB_get_pixel()  clobbers(X,Y) -> ubyte @A
+romsub $ff08 = FB_get_pixels()  clobbers(A,X,Y)         ; uses ptr=r0, count=r1
+romsub $ff0b = FB_set_pixel(ubyte color @A)  clobbers(A,X,Y)
+romsub $ff0e = FB_set_pixels()  clobbers(A,X,Y)         ; uses ptr=r0, count=r1
+romsub $ff11 = FB_set_8_pixels(ubyte pattern @A, ubyte color @X)  clobbers(A,X,Y)
+romsub $ff14 = FB_set_8_pixels_opaque(ubyte pattern @A, ubyte color1 @X, ubyte color2 @Y)  clobbers(A,X,Y)  ; also uses mask=r0L
+romsub $ff17 = FB_fill_pixels(ubyte color @A)  clobbers(A,X,Y)   ; also uses count=r0, step=r1
+romsub $ff1a = FB_filter_pixels()  clobbers(A,X,Y)      ; uses ptr=r0, count=r1
+romsub $ff1d = FB_move_pixels()  clobbers(A,X,Y)        ; uses sx=r0, sy=r1, tx=r2, ty=r3, count=r4
+
+; misc
+romsub $fef0 = sprite_set_image(ubyte number @A, ubyte width @X, ubyte height @Y, ubyte apply_mask @Pc)  clobbers(A,X,Y) -> ubyte @Pc  ; also uses pixels=r0, mask=r1, bpp=r2L
+romsub $fef3 = sprite_set_position(ubyte number @A)  clobbers(A,X,Y)  ; also uses x=r0 and y=r1
+romsub $fee4 = memory_fill(ubyte value @A)  clobbers(A,X,Y)      ; uses address=r0, num_bytes=r1
+romsub $fee7 = memory_copy()  clobbers(A,X,Y)                    ; uses source=r0, target=r1, num_bytes=r2
+romsub $feea = memory_crc()  clobbers(A,X,Y)                     ; uses address=r0, num_bytes=r1     result->r2
+romsub $feed = memory_decompress()  clobbers(A,X,Y)              ; uses input=r0, output=r1     result->r1
+romsub $fedb = console_init()  clobbers(A,X,Y)           ; uses x=r0, y=r1, width=r2, height=r3
+romsub $fede = console_put_char(ubyte char @A, ubyte wrapping @Pc)  clobbers(A,X,Y)
+romsub $fee1 = console_get_char()  clobbers(X,Y) -> ubyte @A
+romsub $fed8 = console_put_image()  clobbers(A,X,Y)      ; uses ptr=r0, width=r1, height=r2
+romsub $fed5 = console_set_paging_message()  clobbers(A,X,Y)     ; uses messageptr=r0
+romsub $fed2 = kbdbuf_put(ubyte key @A)  clobbers(A,X,Y)
+romsub $fecf = entropy_get() -> ubyte @A, ubyte @X, ubyte @Y
+romsub $fecc = monitor()  clobbers(A,X,Y)
+
+
+
+; ---- end of kernal routines ----
+
+asmsub init_system()  {
+    ; Initializes the machine to a sane starting state.
+    ; Called automatically by the loader program logic.
+    %asm {{
+        sei
+        cld
+        ;stz  $00
+        ;stz  $01
+        ;stz  d1prb      ; select rom bank 0
+        lda  #$80
+        sta  VERA_CTRL
+        jsr  c64.IOINIT
+        jsr  c64.RESTOR
+        jsr  c64.CINT
+        lda  #0
+        tax
+        tay
+        clc
+        clv
+        cli
+        rts
+    }}
+}
+
+}

compiler/res/prog8lib/cx16textio.p8

@@ -0,0 +1,344 @@
+; Prog8 definitions for the Text I/O and Screen routines for the CommanderX16
+;
+; Written by Irmen de Jong (irmen@razorvine.net) - license: GNU GPL 3.0
+;
+; indent format: TABS, size=8
+
+%target cx16
+%import cx16lib
+%import conv
+
+
+txt {
+
+sub  clear_screen() {
+    c64.CHROUT(147)         ; clear screen (spaces)
+}
+
+
+asmsub  fill_screen (ubyte char @ A, ubyte txtcolor @ Y) clobbers(A)  {
+	; ---- fill the character screen with the given fill character and character color.
+	%asm {{
+        sta  P8ZP_SCRATCH_W1        ; fillchar
+        sty  P8ZP_SCRATCH_W1+1      ; textcolor
+        phx
+        jsr  c64.SCREEN             ; get dimensions in X/Y
+        dex
+        dey
+        txa
+        asl  a
+        adc  #1
+        sta  P8ZP_SCRATCH_B1
+-       ldx  P8ZP_SCRATCH_B1
+-       stz  cx16.VERA_ADDR_H
+        stx  cx16.VERA_ADDR_L
+        sty  cx16.VERA_ADDR_M
+        lda  cx16.VERA_DATA0
+        and  #$f0
+        ora  P8ZP_SCRATCH_W1+1
+        sta  cx16.VERA_DATA0
+        dex
+        stz  cx16.VERA_ADDR_H
+        stx  cx16.VERA_ADDR_L
+        sty  cx16.VERA_ADDR_M
+        lda  P8ZP_SCRATCH_W1
+        sta  cx16.VERA_DATA0
+        dex
+        cpx  #255
+        bne  -
+        dey
+        bpl  --
+        plx
+        rts
+    }}
+
+}
+
+asmsub  clear_screenchars (ubyte char @ A) clobbers(Y)  {
+	; ---- clear the character screen with the given fill character (leaves colors)
+	;      (assumes screen matrix is at the default address)
+	%asm {{
+        pha
+        phx
+        jsr  c64.SCREEN             ; get dimensions in X/Y
+        dex
+        dey
+        txa
+        asl  a
+        sta  P8ZP_SCRATCH_B1
+        pla
+-       ldx  P8ZP_SCRATCH_B1
+-       stz  cx16.VERA_ADDR_H
+        stx  cx16.VERA_ADDR_L
+        sty  cx16.VERA_ADDR_M
+        sta  cx16.VERA_DATA0
+        dex
+        dex
+        cpx  #254
+        bne  -
+        dey
+        bpl  --
+        plx
+        rts
+        }}
+}
+
+
+ubyte[16] color_to_charcode = [$90,$05,$1c,$9f,$9c,$1e,$1f,$9e,$81,$95,$96,$97,$98,$99,$9a,$9b]
+
+sub color (ubyte txtcol) {
+    c64.CHROUT(color_to_charcode[txtcol & 15])
+}
+
+sub color2 (ubyte txtcol, ubyte bgcol) {
+    c64.CHROUT(color_to_charcode[bgcol & 15])
+    c64.CHROUT(1)       ; switch fg and bg colors
+    c64.CHROUT(color_to_charcode[txtcol & 15])
+}
+
+asmsub  print (str text @ AY) clobbers(A,Y)  {
+	; ---- print null terminated string from A/Y
+	; note: the compiler contains an optimization that will replace
+	;       a call to this subroutine with a string argument of just one char,
+	;       by just one call to c64.CHROUT of that single char.
+	%asm {{
+		sta  P8ZP_SCRATCH_B1
+		sty  P8ZP_SCRATCH_REG
+		ldy  #0
+-		lda  (P8ZP_SCRATCH_B1),y
+		beq  +
+		jsr  c64.CHROUT
+		iny
+		bne  -
++		rts
+	}}
+}
+
+asmsub  print_ub0  (ubyte value @ A) clobbers(A,Y)  {
+	; ---- print the ubyte in A in decimal form, with left padding 0s (3 positions total)
+	%asm {{
+		phx
+		jsr  conv.ubyte2decimal
+		pha
+		tya
+		jsr  c64.CHROUT
+		pla
+		jsr  c64.CHROUT
+		txa
+		jsr  c64.CHROUT
+		plx
+		rts
+	}}
+}
+
+asmsub  print_ub  (ubyte value @ A) clobbers(A,Y)  {
+	; ---- print the ubyte in A in decimal form, without left padding 0s
+	%asm {{
+		phx
+		jsr  conv.ubyte2decimal
+_print_byte_digits
+		pha
+		cpy  #'0'
+		beq  +
+		tya
+		jsr  c64.CHROUT
+		pla
+		jsr  c64.CHROUT
+		jmp  _ones
++       pla
+        cmp  #'0'
+        beq  _ones
+        jsr  c64.CHROUT
+_ones   txa
+		jsr  c64.CHROUT
+		plx
+		rts
+	}}
+}
+
+asmsub  print_b  (byte value @ A) clobbers(A,Y)  {
+	; ---- print the byte in A in decimal form, without left padding 0s
+	%asm {{
+		phx
+		pha
+		cmp  #0
+		bpl  +
+		lda  #'-'
+		jsr  c64.CHROUT
++		pla
+		jsr  conv.byte2decimal
+		jmp  print_ub._print_byte_digits
+	}}
+}
+
+asmsub  print_ubhex  (ubyte value @ A, ubyte prefix @ Pc) clobbers(A,Y)  {
+	; ---- print the ubyte in A in hex form (if Carry is set, a radix prefix '$' is printed as well)
+	%asm {{
+		phx
+		bcc  +
+		pha
+		lda  #'$'
+		jsr  c64.CHROUT
+		pla
++		jsr  conv.ubyte2hex
+		jsr  c64.CHROUT
+		tya
+		jsr  c64.CHROUT
+		plx
+		rts
+	}}
+}
+
+asmsub  print_ubbin  (ubyte value @ A, ubyte prefix @ Pc) clobbers(A,Y)  {
+	; ---- print the ubyte in A in binary form (if Carry is set, a radix prefix '%' is printed as well)
+	%asm {{
+		phx
+		sta  P8ZP_SCRATCH_B1
+		bcc  +
+		lda  #'%'
+		jsr  c64.CHROUT
++		ldy  #8
+-		lda  #'0'
+		asl  P8ZP_SCRATCH_B1
+		bcc  +
+		lda  #'1'
++		jsr  c64.CHROUT
+		dey
+		bne  -
+		plx
+		rts
+	}}
+}
+
+asmsub  print_uwbin  (uword value @ AY, ubyte prefix @ Pc) clobbers(A,Y)  {
+	; ---- print the uword in A/Y in binary form (if Carry is set, a radix prefix '%' is printed as well)
+	%asm {{
+		pha
+		tya
+		jsr  print_ubbin
+		pla
+		clc
+		jmp  print_ubbin
+	}}
+}
+
+asmsub  print_uwhex  (uword value @ AY, ubyte prefix @ Pc) clobbers(A,Y)  {
+	; ---- print the uword in A/Y in hexadecimal form (4 digits)
+	;      (if Carry is set, a radix prefix '$' is printed as well)
+	%asm {{
+		pha
+		tya
+		jsr  print_ubhex
+		pla
+		clc
+		jmp  print_ubhex
+	}}
+}
+
+asmsub  print_uw0  (uword value @ AY) clobbers(A,Y)  {
+	; ---- print the uword in A/Y in decimal form, with left padding 0s (5 positions total)
+	%asm {{
+	    phx
+		jsr  conv.uword2decimal
+		ldy  #0
+-		lda  conv.uword2decimal.decTenThousands,y
+        beq  +
+		jsr  c64.CHROUT
+		iny
+		bne  -
++		plx
+		rts
+	}}
+}
+
+asmsub  print_uw  (uword value @ AY) clobbers(A,Y)  {
+	; ---- print the uword in A/Y in decimal form, without left padding 0s
+	%asm {{
+	    phx
+		jsr  conv.uword2decimal
+		plx
+		ldy  #0
+-		lda  conv.uword2decimal.decTenThousands,y
+		beq  _allzero
+		cmp  #'0'
+		bne  _gotdigit
+		iny
+		bne  -
+
+_gotdigit
+		jsr  c64.CHROUT
+		iny
+		lda  conv.uword2decimal.decTenThousands,y
+		bne  _gotdigit
+		rts
+_allzero
+        lda  #'0'
+        jmp  c64.CHROUT
+	}}
+}
+
+asmsub  print_w  (word value @ AY) clobbers(A,Y)  {
+	; ---- print the (signed) word in A/Y in decimal form, without left padding 0's
+	%asm {{
+		cpy  #0
+		bpl  +
+		pha
+		lda  #'-'
+		jsr  c64.CHROUT
+		tya
+		eor  #255
+		tay
+		pla
+		eor  #255
+		clc
+		adc  #1
+		bcc  +
+		iny
++		jmp  print_uw
+	}}
+}
+
+; TODO implement the "missing" txtio subroutines
+
+sub  setcc  (ubyte column, ubyte row, ubyte char, ubyte charcolor)  {
+	; ---- set char+color at the given position on the screen
+	%asm {{
+	    phx
+		lda  column
+		asl  a
+		tax
+		ldy  row
+		lda  charcolor
+		and  #$0f
+	    sta  P8ZP_SCRATCH_B1
+        stz  cx16.VERA_ADDR_H
+        stx  cx16.VERA_ADDR_L
+        sty  cx16.VERA_ADDR_M
+        lda  char
+        sta  cx16.VERA_DATA0
+        inx
+        stz  cx16.VERA_ADDR_H
+        stx  cx16.VERA_ADDR_L
+        sty  cx16.VERA_ADDR_M
+        lda  cx16.VERA_DATA0
+        and  #$f0
+        ora  P8ZP_SCRATCH_B1
+        sta  cx16.VERA_DATA0
+		plx
+		rts
+    }}
+}
+
+asmsub  plot  (ubyte col @ Y, ubyte row @ A) clobbers(A) {
+	; ---- safe wrapper around PLOT kernel routine, to save the X register.
+	%asm  {{
+		phx
+		tax
+		clc
+		jsr  c64.PLOT
+		plx
+		rts
+	}}
+}
+
+}

compiler/res/prog8lib/math.p8

@@ -4,8 +4,6 @@
 ;
 ; indent format: TABS, size=8
 
-%import c64lib
-
 math {
 	%asminclude "library:math.asm", ""
 }

compiler/res/prog8lib/prog8lib.p8

@@ -4,8 +4,6 @@
 ;
 ; indent format: TABS, size=8
 
-%import c64lib
-
 prog8_lib {
 	%asminclude "library:prog8lib.asm", ""
 }

compiler/res/version.txt

@@ -1 +1 @@
-3.0
+4.2

compiler/src/prog8/CompilerMain.kt

@@ -4,12 +4,10 @@ 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.compiler.target.CompilationTarget
-import prog8.compiler.target.c64.C64MachineDefinition
-import prog8.compiler.target.c64.Petscii
-import prog8.compiler.target.c64.codegen.AsmGen
 import prog8.parser.ParsingFailedError
-import java.io.IOException
 import java.nio.file.FileSystems
 import java.nio.file.Path
 import java.nio.file.StandardWatchEventKinds
@@ -35,12 +33,13 @@ fun pathFrom(stringPath: String, vararg rest: String): Path  = FileSystems.getDe
 
 private fun compileMain(args: Array<String>) {
     val cli = CommandLineInterface("prog8compiler")
-    val startEmulator by cli.flagArgument("-emu", "auto-start the Vice C-64 emulator after successful compilation")
+    val startEmulator by cli.flagArgument("-emu", "auto-start emulator after successful compilation")
     val outputDir by cli.flagValueArgument("-out", "directory", "directory for output files instead of current directory", ".")
     val dontWriteAssembly by cli.flagArgument("-noasm", "don't create assembly code")
     val dontOptimize by cli.flagArgument("-noopt", "don't perform any optimizations")
     val watchMode by cli.flagArgument("-watch", "continuous compilation mode (watches for file changes), greatly increases compilation speed")
-    val compilationTarget by cli.flagValueArgument("-target", "compilertarget", "target output of the compiler, currently only 'c64' (C64 6502 assembly) available", "c64")
+    val compilationTarget by cli.flagValueArgument("-target", "compilertarget",
+            "target output of the compiler, currently '${C64Target.name}' and '${Cx16Target.name}' available", C64Target.name)
     val moduleFiles by cli.positionalArgumentsList("modules", "main module file(s) to compile", minArgs = 1)
 
     try {
@@ -49,26 +48,6 @@ private fun compileMain(args: Array<String>) {
         exitProcess(1)
     }
 
-    when(compilationTarget) {
-        "c64" -> {
-            with(CompilationTarget) {
-                name = "c64"
-                machine = C64MachineDefinition
-                encodeString = { str, altEncoding ->
-                    if(altEncoding) Petscii.encodeScreencode(str, true) else Petscii.encodePetscii(str, true)
-                }
-                decodeString = { bytes, altEncoding ->
-                    if(altEncoding) Petscii.decodeScreencode(bytes, true) else Petscii.decodePetscii(bytes, true)
-                }
-                asmGenerator = ::AsmGen
-            }
-        }
-        else -> {
-            System.err.println("invalid compilation target")
-            exitProcess(1)
-        }
-    }
-
     val outputPath = pathFrom(outputDir)
     if(!outputPath.toFile().isDirectory) {
         System.err.println("Output path doesn't exist")
@@ -83,7 +62,7 @@ private fun compileMain(args: Array<String>) {
             println("Continuous watch mode active. Main module: $filepath")
 
             try {
-                val compilationResult = compileProgram(filepath, !dontOptimize, !dontWriteAssembly, outputDir=outputPath)
+                val compilationResult = compileProgram(filepath, !dontOptimize, !dontWriteAssembly, compilationTarget, outputPath)
                 println("Imported files (now watching:)")
                 for (importedFile in compilationResult.importedFiles) {
                     print("  ")
@@ -108,7 +87,7 @@ private fun compileMain(args: Array<String>) {
             val filepath = pathFrom(filepathRaw).normalize()
             val compilationResult: CompilationResult
             try {
-                compilationResult = compileProgram(filepath, !dontOptimize, !dontWriteAssembly, outputDir=outputPath)
+                compilationResult = compileProgram(filepath, !dontOptimize, !dontWriteAssembly, compilationTarget, outputPath)
                 if(!compilationResult.success)
                     exitProcess(1)
             } catch (x: ParsingFailedError) {
@@ -121,20 +100,7 @@ private fun compileMain(args: Array<String>) {
                 if (compilationResult.programName.isEmpty())
                     println("\nCan't start emulator because no program was assembled.")
                 else if(startEmulator) {
-                    for(emulator in listOf("x64sc", "x64")) {
-                        println("\nStarting C-64 emulator $emulator...")
-                        val cmdline = listOf(emulator, "-silent", "-moncommands", "${compilationResult.programName}.vice-mon-list",
-                                "-autostartprgmode", "1", "-autostart-warp", "-autostart", compilationResult.programName + ".prg")
-                        val processb = ProcessBuilder(cmdline).inheritIO()
-                        val process: Process
-                        try {
-                            process=processb.start()
-                        } catch(x: IOException) {
-                            continue  // try the next emulator executable
-                        }
-                        process.waitFor()
-                        break
-                    }
+                    CompilationTarget.instance.machine.launchEmulator(compilationResult.programName)
                 }
             }
         }

compiler/src/prog8/ast/AstToSourceCode.kt

@@ -140,7 +140,7 @@ class AstToSourceCode(val output: (text: String) -> Unit, val program: Program):
                             param.second.stack -> "stack"
                             param.second.registerOrPair!=null -> param.second.registerOrPair.toString()
                             param.second.statusflag!=null -> param.second.statusflag.toString()
-                            else -> "?????1"
+                            else -> "?????"
                         }
                 output("${datatypeString(param.first.type)} ${param.first.name} @$reg")
                 if(param.first!==subroutine.parameters.last())
@@ -287,12 +287,19 @@ class AstToSourceCode(val output: (text: String) -> Unit, val program: Program):
     }
 
     override fun visit(assignment: Assignment) {
-        assignment.target.accept(this)
-        if (assignment.aug_op != null && assignment.aug_op != "setvalue")
-            output(" ${assignment.aug_op} ")
-        else
+        val binExpr = assignment.value as? BinaryExpression
+        if(binExpr!=null && binExpr.left isSameAs assignment.target
+                && binExpr.operator !in setOf("and", "or", "xor")
+                && binExpr.operator !in comparisonOperators) {
+            // we only support the inplace assignments of the form A = A <operator> <value>
+            assignment.target.accept(this)
+            output(" ${binExpr.operator}= ")
+            binExpr.right.accept(this)
+        } else {
+            assignment.target.accept(this)
             output(" = ")
-        assignment.value.accept(this)
+            assignment.value.accept(this)
+        }
     }
 
     override fun visit(postIncrDecr: PostIncrDecr) {
@@ -300,10 +307,6 @@ class AstToSourceCode(val output: (text: String) -> Unit, val program: Program):
         output(postIncrDecr.operator)
     }
 
-    override fun visit(contStmt: Continue) {
-        output("continue")
-    }
-
     override fun visit(breakStmt: Break) {
         output("break")
     }
@@ -426,8 +429,4 @@ class AstToSourceCode(val output: (text: String) -> Unit, val program: Program):
             whenChoice.statements.accept(this)
         outputln("")
     }
-
-    override fun visit(nopStatement: NopStatement) {
-        output("; NOP @ ${nopStatement.position}  $nopStatement")
-    }
 }

compiler/src/prog8/ast/AstToplevel.kt

@@ -314,9 +314,9 @@ class GlobalNamespace(val modules: List<Module>): Node, INameScope {
         }
         // lookup something from the module.
         return when (val stmt = localContext.definingModule().lookup(scopedName, localContext)) {
-            is Label, is VarDecl, is Block, is Subroutine -> stmt
+            is Label, is VarDecl, is Block, is Subroutine, is StructDecl -> stmt
             null -> null
-            else -> throw SyntaxError("wrong identifier target for $scopedName: $stmt", stmt.position)
+            else -> throw SyntaxError("invalid identifier target type", stmt.position)
         }
     }
 }

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

@@ -161,14 +161,15 @@ private fun prog8Parser.StatementContext.toAst() : Statement {
     if(vardecl!=null) return vardecl
 
     assignment()?.let {
-        return Assignment(it.assign_target().toAst(), null, it.expression().toAst(), it.toPosition())
+        return Assignment(it.assign_target().toAst(), it.expression().toAst(), it.toPosition())
     }
 
     augassignment()?.let {
-        return Assignment(it.assign_target().toAst(),
-                it.operator.text,
-                it.expression().toAst(),
-                it.toPosition())
+        // replace A += X  with  A = A + X
+        val target = it.assign_target().toAst()
+        val oper = it.operator.text.substringBefore('=')
+        val expression = BinaryExpression(target.toExpression(), oper, it.expression().toAst(), it.expression().toPosition())
+        return Assignment(it.assign_target().toAst(), expression, it.toPosition())
     }
 
     postincrdecr()?.let {
@@ -217,9 +218,6 @@ private fun prog8Parser.StatementContext.toAst() : Statement {
     val breakstmt = breakstmt()?.toAst()
     if(breakstmt!=null) return breakstmt
 
-    val continuestmt = continuestmt()?.toAst()
-    if(continuestmt!=null) return continuestmt
-
     val whenstmt = whenstmt()?.toAst()
     if(whenstmt!=null) return whenstmt
 
@@ -256,7 +254,7 @@ private fun prog8Parser.Asmsub_declContext.toAst(): AsmsubDecl {
     val clobbers = asmsub_clobbers()?.clobber()?.toAst() ?: emptySet()
     val normalParameters = params.map { SubroutineParameter(it.name, it.type, it.position) }
     val normalReturntypes = returns.map { it.type }
-    val paramRegisters = params.map { RegisterOrStatusflag(it.registerOrPair, it.statusflag, it.stack) }
+    val paramRegisters = params.map { RegisterOrStatusflag(it.registerOrPair, it.statusflag, false) }
     val returnRegisters = returns.map { RegisterOrStatusflag(it.registerOrPair, it.statusflag, it.stack) }
     return AsmsubDecl(name, normalParameters, normalReturntypes, paramRegisters, returnRegisters, clobbers)
 }
@@ -265,7 +263,7 @@ private class AsmSubroutineParameter(name: String,
                                      type: DataType,
                                      val registerOrPair: RegisterOrPair?,
                                      val statusflag: Statusflag?,
-                                     val stack: Boolean,
+                                     // TODO implement: val stack: Boolean,
                                      position: Position) : SubroutineParameter(name, type, position)
 
 private class AsmSubroutineReturn(val type: DataType,
@@ -304,11 +302,10 @@ private fun prog8Parser.Asmsub_paramsContext.toAst(): List<AsmSubroutineParamete
         when (val name = register.nameInSource.single()) {
             in RegisterOrPair.names -> registerorpair = RegisterOrPair.valueOf(name)
             in Statusflag.names -> statusregister = Statusflag.valueOf(name)
-            else -> throw FatalAstException("invalid register or status flag in $it")
+            else -> throw FatalAstException("invalid register or status flag '$name'")
         }
     }
-    AsmSubroutineParameter(vardecl.varname.text, datatype, registerorpair, statusregister,
-            !it.stack?.text.isNullOrEmpty(), toPosition())
+    AsmSubroutineParameter(vardecl.varname.text, datatype, registerorpair, statusregister, toPosition())
 }
 
 private fun prog8Parser.Functioncall_stmtContext.toAst(): Statement {
@@ -474,7 +471,7 @@ private fun prog8Parser.ExpressionContext.toAst() : Expression {
                 litval.charliteral()!=null -> {
                     try {
                         val cc=litval.charliteral()
-                        NumericLiteralValue(DataType.UBYTE, CompilationTarget.encodeString(
+                        NumericLiteralValue(DataType.UBYTE, CompilationTarget.instance.encodeString(
                                 unescape(litval.charliteral().SINGLECHAR().text, litval.toPosition()),
                                 litval.charliteral().ALT_STRING_ENCODING()!=null)[0], litval.toPosition())
                     } catch (ce: CharConversionException) {
@@ -593,8 +590,6 @@ private fun prog8Parser.ForloopContext.toAst(): ForLoop {
     return ForLoop(loopvar, iterable, scope, toPosition())
 }
 
-private fun prog8Parser.ContinuestmtContext.toAst() = Continue(toPosition())
-
 private fun prog8Parser.BreakstmtContext.toAst() = Break(toPosition())
 
 private fun prog8Parser.WhileloopContext.toAst(): WhileLoop {

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

@@ -21,10 +21,9 @@ enum class DataType {
     STRUCT;             // pass by reference
 
     /**
-     * is the type assignable to the given other type?
+     * is the type assignable to the given other type (perhaps via a typecast) without loss of precision?
      */
     infix fun isAssignableTo(targetType: DataType) =
-            // what types are assignable to others, perhaps via a typecast, without loss of precision?
             when(this) {
                 UBYTE -> targetType in setOf(UBYTE, WORD, UWORD, FLOAT)
                 BYTE -> targetType in setOf(BYTE, WORD, FLOAT)
@@ -57,8 +56,8 @@ enum class DataType {
         return when(this) {
             in ByteDatatypes -> 1
             in WordDatatypes -> 2
-            FLOAT -> CompilationTarget.machine.FLOAT_MEM_SIZE
-            in PassByReferenceDatatypes -> 2
+            FLOAT -> CompilationTarget.instance.machine.FLOAT_MEM_SIZE
+            in PassByReferenceDatatypes -> CompilationTarget.instance.machine.POINTER_MEM_SIZE
             else -> -9999999
         }
     }

compiler/src/prog8/ast/base/Extensions.kt

@@ -5,7 +5,6 @@ import prog8.ast.Program
 import prog8.ast.processing.*
 import prog8.compiler.CompilationOptions
 import prog8.compiler.BeforeAsmGenerationAstChanger
-import prog8.optimizer.AssignmentTransformer
 
 
 internal fun Program.checkValid(compilerOptions: CompilationOptions, errors: ErrorReporter) {
@@ -36,17 +35,6 @@ internal fun Program.verifyFunctionArgTypes() {
     fixer.visit(this)
 }
 
-internal fun Program.transformAssignments(errors: ErrorReporter) {
-    val transform = AssignmentTransformer(this, errors)
-    transform.visit(this)
-    while(transform.optimizationsDone>0 && errors.isEmpty()) {
-        transform.applyModifications()
-        transform.optimizationsDone = 0
-        transform.visit(this)
-    }
-    transform.applyModifications()
-}
-
 internal fun Module.checkImportedValid() {
     val imr = ImportedModuleDirectiveRemover()
     imr.visit(this, this.parent)

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

@@ -16,6 +16,7 @@ import kotlin.math.abs
 
 
 val associativeOperators = setOf("+", "*", "&", "|", "^", "or", "and", "xor", "==", "!=")
+val comparisonOperators = setOf("==", "!=", "<", ">", "<=", ">=")
 
 
 sealed class Expression: Node {
@@ -25,6 +26,8 @@ sealed class Expression: Node {
     abstract fun referencesIdentifiers(vararg name: String): Boolean
     abstract fun inferType(program: Program): InferredTypes.InferredType
 
+    infix fun isSameAs(assigntarget: AssignTarget) = assigntarget.isSameAs(this)
+
     infix fun isSameAs(other: Expression): Boolean {
         if(this===other)
             return true
@@ -41,6 +44,23 @@ sealed class Expression: Node {
                 (other is ArrayIndexedExpression && other.identifier.nameInSource == identifier.nameInSource
                         && other.arrayspec.index isSameAs arrayspec.index)
             }
+            is DirectMemoryRead -> {
+                (other is DirectMemoryRead && other.addressExpression isSameAs addressExpression)
+            }
+            is TypecastExpression -> {
+                (other is TypecastExpression && other.implicit==implicit && other.type==type && other.expression isSameAs expression)
+            }
+            is AddressOf -> {
+                (other is AddressOf && other.identifier.nameInSource == identifier.nameInSource)
+            }
+            is RangeExpr -> {
+                (other is RangeExpr && other.from==from && other.to==to && other.step==step)
+            }
+            is FunctionCall -> {
+                (other is FunctionCall && other.target.nameInSource == target.nameInSource
+                        && other.args.size == args.size
+                        && other.args.zip(args).all { it.first isSameAs it.second } )
+            }
             else -> other==this
         }
     }
@@ -275,9 +295,11 @@ class TypecastExpression(var expression: Expression, var type: DataType, val imp
     override fun inferType(program: Program): InferredTypes.InferredType = InferredTypes.knownFor(type)
     override fun constValue(program: Program): NumericLiteralValue? {
         val cv = expression.constValue(program) ?: return null
-        return cv.cast(type)
-        // val value = RuntimeValue(cv.type, cv.asNumericValue!!).cast(type)
-        // return LiteralValue.fromNumber(value.numericValue(), value.type, position).cast(type)
+        val cast = cv.cast(type)
+        return if(cast.isValid)
+            cast.valueOrZero()
+        else
+            null
     }
 
     override fun toString(): String {
@@ -396,62 +418,66 @@ class NumericLiteralValue(val type: DataType,    // only numerical types allowed
 
     operator fun compareTo(other: NumericLiteralValue): Int = number.toDouble().compareTo(other.number.toDouble())
 
-    fun cast(targettype: DataType): NumericLiteralValue {
+    class CastValue(val isValid: Boolean, private val value: NumericLiteralValue?) {
+        fun valueOrZero() = if(isValid) value!! else NumericLiteralValue(DataType.UBYTE, 0, Position.DUMMY)
+    }
+
+    fun cast(targettype: DataType): CastValue {
         if(type==targettype)
-            return this
+            return CastValue(true, this)
         val numval = number.toDouble()
         when(type) {
             DataType.UBYTE -> {
                 if(targettype== DataType.BYTE && numval <= 127)
-                    return NumericLiteralValue(targettype, number.toShort(), position)
+                    return CastValue(true, NumericLiteralValue(targettype, number.toShort(), position))
                 if(targettype== DataType.WORD || targettype== DataType.UWORD)
-                    return NumericLiteralValue(targettype, number.toInt(), position)
+                    return CastValue(true, NumericLiteralValue(targettype, number.toInt(), position))
                 if(targettype== DataType.FLOAT)
-                    return NumericLiteralValue(targettype, number.toDouble(), position)
+                    return CastValue(true, NumericLiteralValue(targettype, number.toDouble(), position))
             }
             DataType.BYTE -> {
                 if(targettype== DataType.UBYTE && numval >= 0)
-                    return NumericLiteralValue(targettype, number.toShort(), position)
+                    return CastValue(true, NumericLiteralValue(targettype, number.toShort(), position))
                 if(targettype== DataType.UWORD && numval >= 0)
-                    return NumericLiteralValue(targettype, number.toInt(), position)
+                    return CastValue(true, NumericLiteralValue(targettype, number.toInt(), position))
                 if(targettype== DataType.WORD)
-                    return NumericLiteralValue(targettype, number.toInt(), position)
+                    return CastValue(true, NumericLiteralValue(targettype, number.toInt(), position))
                 if(targettype== DataType.FLOAT)
-                    return NumericLiteralValue(targettype, number.toDouble(), position)
+                    return CastValue(true, NumericLiteralValue(targettype, number.toDouble(), position))
             }
             DataType.UWORD -> {
                 if(targettype== DataType.BYTE && numval <= 127)
-                    return NumericLiteralValue(targettype, number.toShort(), position)
+                    return CastValue(true, NumericLiteralValue(targettype, number.toShort(), position))
                 if(targettype== DataType.UBYTE && numval <= 255)
-                    return NumericLiteralValue(targettype, number.toShort(), position)
+                    return CastValue(true, NumericLiteralValue(targettype, number.toShort(), position))
                 if(targettype== DataType.WORD && numval <= 32767)
-                    return NumericLiteralValue(targettype, number.toInt(), position)
+                    return CastValue(true, NumericLiteralValue(targettype, number.toInt(), position))
                 if(targettype== DataType.FLOAT)
-                    return NumericLiteralValue(targettype, number.toDouble(), position)
+                    return CastValue(true, NumericLiteralValue(targettype, number.toDouble(), position))
             }
             DataType.WORD -> {
                 if(targettype== DataType.BYTE && numval >= -128 && numval <=127)
-                    return NumericLiteralValue(targettype, number.toShort(), position)
+                    return CastValue(true, NumericLiteralValue(targettype, number.toShort(), position))
                 if(targettype== DataType.UBYTE && numval >= 0 && numval <= 255)
-                    return NumericLiteralValue(targettype, number.toShort(), position)
+                    return CastValue(true, NumericLiteralValue(targettype, number.toShort(), position))
                 if(targettype== DataType.UWORD && numval >=0)
-                    return NumericLiteralValue(targettype, number.toInt(), position)
+                    return CastValue(true, NumericLiteralValue(targettype, number.toInt(), position))
                 if(targettype== DataType.FLOAT)
-                    return NumericLiteralValue(targettype, number.toDouble(), position)
+                    return CastValue(true, NumericLiteralValue(targettype, number.toDouble(), position))
             }
             DataType.FLOAT -> {
                 if (targettype == DataType.BYTE && numval >= -128 && numval <=127)
-                    return NumericLiteralValue(targettype, number.toShort(), position)
+                    return CastValue(true, NumericLiteralValue(targettype, number.toShort(), position))
                 if (targettype == DataType.UBYTE && numval >=0 && numval <= 255)
-                    return NumericLiteralValue(targettype, number.toShort(), position)
+                    return CastValue(true, NumericLiteralValue(targettype, number.toShort(), position))
                 if (targettype == DataType.WORD && numval >= -32768 && numval <= 32767)
-                    return NumericLiteralValue(targettype, number.toInt(), position)
+                    return CastValue(true, NumericLiteralValue(targettype, number.toInt(), position))
                 if (targettype == DataType.UWORD && numval >=0 && numval <= 65535)
-                    return NumericLiteralValue(targettype, number.toInt(), position)
+                    return CastValue(true, NumericLiteralValue(targettype, number.toInt(), position))
             }
             else -> {}
         }
-        throw ExpressionError("can't cast $type into $targettype", position)
+        return CastValue(false, null)
     }
 }
 
@@ -561,14 +587,14 @@ class ArrayLiteralValue(val type: InferredTypes.InferredType,     // inferred be
                 if(num==null) {
                     // an array of UWORDs could possibly also contain AddressOfs, other stuff can't be casted
                     if (elementType != DataType.UWORD || it !is AddressOf)
-                        return null
+                        return null  // can't cast a value of  the array, abort
                     it
                 } else {
-                    try {
-                        num.cast(elementType)
-                    } catch(x: ExpressionError) {
-                        return null
-                    }
+                    val cast = num.cast(elementType)
+                    if(cast.isValid)
+                        cast.valueOrZero()
+                    else
+                        return null // can't cast a value of the array, abort
                 }
             }.toTypedArray()
             return ArrayLiteralValue(InferredTypes.InferredType.known(targettype), castArray, position = position)
@@ -616,7 +642,14 @@ class RangeExpr(var from: Expression,
             fromDt istype DataType.STR && toDt istype DataType.STR -> InferredTypes.knownFor(DataType.STR)
             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 -> InferredTypes.knownFor(DataType.ARRAY_UB)
+            else -> {
+                val fdt = fromDt.typeOrElse(DataType.STRUCT)
+                val tdt = toDt.typeOrElse(DataType.STRUCT)
+                if(fdt largerThan tdt)
+                    InferredTypes.knownFor(ElementArrayTypes.getValue(fdt))
+                else
+                    InferredTypes.knownFor(ElementArrayTypes.getValue(tdt))
+            }
         }
     }
     override fun toString(): String {
@@ -638,8 +671,8 @@ class RangeExpr(var from: Expression,
         val toString = to as? StringLiteralValue
         if(fromString!=null && toString!=null ) {
             // string range -> int range over character values
-            fromVal = CompilationTarget.encodeString(fromString.value, fromString.altEncoding)[0].toInt()
-            toVal = CompilationTarget.encodeString(toString.value, fromString.altEncoding)[0].toInt()
+            fromVal = CompilationTarget.instance.encodeString(fromString.value, fromString.altEncoding)[0].toInt()
+            toVal = CompilationTarget.instance.encodeString(toString.value, fromString.altEncoding)[0].toInt()
         } else {
             val fromLv = from as? NumericLiteralValue
             val toLv = to as? NumericLiteralValue
@@ -714,11 +747,10 @@ data class IdentifierReference(val nameInSource: List<String>, override val posi
     override fun referencesIdentifiers(vararg name: String): Boolean = nameInSource.last() in name
 
     override fun inferType(program: Program): InferredTypes.InferredType {
-        val targetStmt = targetStatement(program.namespace)
-        return if(targetStmt is VarDecl) {
-            InferredTypes.knownFor(targetStmt.datatype)
-        } else {
-            InferredTypes.InferredType.unknown()
+        return when (val targetStmt = targetStatement(program.namespace)) {
+            is VarDecl -> InferredTypes.knownFor(targetStmt.datatype)
+            is StructDecl -> InferredTypes.knownFor(DataType.STRUCT)
+            else -> InferredTypes.InferredType.unknown()
         }
     }
 

compiler/src/prog8/ast/processing/AstChecker.kt

@@ -7,7 +7,9 @@ import prog8.ast.base.*
 import prog8.ast.expressions.*
 import prog8.ast.statements.*
 import prog8.compiler.CompilationOptions
+import prog8.compiler.target.C64Target
 import prog8.compiler.target.CompilationTarget
+import prog8.compiler.target.Cx16Target
 import prog8.functions.BuiltinFunctions
 import java.io.File
 
@@ -118,6 +120,11 @@ internal class AstChecker(private val program: Program,
             if(loopvar==null || loopvar.type== VarDeclType.CONST) {
                 errors.err("for loop requires a variable to loop with", forLoop.position)
             } else {
+
+                fun checkLoopRangeValues() {
+
+                }
+
                 when (loopvar.datatype) {
                     DataType.UBYTE -> {
                         if(iterableDt!= DataType.UBYTE && iterableDt!= DataType.ARRAY_UB && iterableDt != DataType.STR)
@@ -142,6 +149,22 @@ internal class AstChecker(private val program: Program,
                     }
                     else -> errors.err("loop variable must be numeric type", forLoop.position)
                 }
+                if(errors.isEmpty()) {
+                    // check loop range values
+                    val range = forLoop.iterable as? RangeExpr
+                    if(range!=null) {
+                        val from = range.from as? NumericLiteralValue
+                        val to = range.to as? NumericLiteralValue
+                        if(from != null)
+                            checkValueTypeAndRange(loopvar.datatype, from)
+                        else if(!range.from.inferType(program).istype(loopvar.datatype))
+                            errors.err("range start value is incompatible with loop variable type", range.position)
+                        if(to != null)
+                            checkValueTypeAndRange(loopvar.datatype, to)
+                        else if(!range.to.inferType(program).istype(loopvar.datatype))
+                            errors.err("range end value is incompatible with loop variable type", range.position)
+                    }
+                }
             }
         }
 
@@ -304,13 +327,10 @@ internal class AstChecker(private val program: Program,
         } else {
             // Pass-by-reference datatypes can not occur as parameters to a subroutine directly
             // Instead, their reference (address) should be passed (as an UWORD).
-            // The language has no typed pointers at this time.
             if(subroutine.parameters.any{it.type in PassByReferenceDatatypes }) {
-                err("Pass-by-reference types (str, array) cannot occur as a parameter type directly. Instead, use an uword for their address, or access the variable from the outer scope directly.")
+                err("Pass-by-reference types (str, array) cannot occur as a parameter type directly. Instead, use an uword to receive their address, or access the variable from the outer scope directly.")
             }
         }
-
-        visitStatements(subroutine.statements)
     }
 
     override fun visit(untilLoop: UntilLoop) {
@@ -362,8 +382,18 @@ internal class AstChecker(private val program: Program,
             }
         }
 
-        if(assignment.value.inferType(program) != assignment.target.inferType(program, assignment))
-            errors.err("assignment value is of different type as the target", assignment.value.position)
+        val targetDt = assignment.target.inferType(program, assignment)
+        if(assignment.value.inferType(program) != targetDt) {
+            if(targetDt.typeOrElse(DataType.STRUCT) in IterableDatatypes)
+                errors.err("cannot assign value to string or array", assignment.value.position)
+            else
+                errors.err("value's type doesn't match target", assignment.value.position)
+        }
+
+        if(assignment.value is TypecastExpression) {
+            if(assignment.isAugmentable && targetDt.istype(DataType.FLOAT))
+                errors.err("typecasting a float value in-place makes no sense", assignment.value.position)
+        }
 
         super.visit(assignment)
     }
@@ -434,21 +464,20 @@ internal class AstChecker(private val program: Program,
         if(variable==null)
             errors.err("pointer-of operand must be the name of a heap variable", addressOf.position)
         else {
-            if(variable.datatype !in ArrayDatatypes && variable.datatype != DataType.STR && variable.datatype!=DataType.STRUCT)
+            if(variable.datatype !in ArrayDatatypes
+                    && variable.type!=VarDeclType.MEMORY
+                    && variable.datatype != DataType.STR && variable.datatype!=DataType.STRUCT)
                 errors.err("invalid pointer-of operand type", addressOf.position)
         }
         super.visit(addressOf)
     }
 
     override fun visit(decl: VarDecl) {
-        fun err(msg: String, position: Position?=null) {
-            errors.err(msg, position ?: decl.position)
-        }
+        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?.referencesIdentifiers(decl.name) == true || decl.arraysize?.index?.referencesIdentifiers(decl.name) == true) {
+        if(decl.value?.referencesIdentifiers(decl.name) == true || decl.arraysize?.index?.referencesIdentifiers(decl.name) == true)
             err("recursive var declaration")
-        }
 
         // CONST can only occur on simple types (byte, word, float)
         if(decl.type== VarDeclType.CONST) {
@@ -456,10 +485,12 @@ internal class AstChecker(private val program: Program,
                 err("const modifier can only be used on numeric types (byte, word, float)")
         }
 
-        // FLOATS
-        if(!compilerOptions.floats && decl.datatype in setOf(DataType.FLOAT, DataType.ARRAY_F) && decl.type!= VarDeclType.MEMORY) {
+        // FLOATS enabled?
+        if(!compilerOptions.floats && decl.datatype in setOf(DataType.FLOAT, DataType.ARRAY_F) && decl.type!= VarDeclType.MEMORY)
             err("floating point used, but that is not enabled via options")
-        }
+
+        if(decl.datatype == DataType.FLOAT && (decl.zeropage==ZeropageWish.REQUIRE_ZEROPAGE || decl.zeropage==ZeropageWish.PREFER_ZEROPAGE))
+            errors.warn("floating point values won't be placed in Zeropage due to size constraints", decl.position)
 
         // ARRAY without size specifier MUST have an iterable initializer value
         if(decl.isArray && decl.arraysize==null) {
@@ -492,8 +523,7 @@ internal class AstChecker(private val program: Program,
 
                 when(decl.value) {
                     null -> {
-                        // a vardecl without an initial value, don't bother with the rest
-                        return super.visit(decl)
+                        // a vardecl without an initial value, don't bother with it
                     }
                     is RangeExpr -> throw FatalAstException("range expression should have been converted to a true array value")
                     is StringLiteralValue -> {
@@ -529,15 +559,17 @@ internal class AstChecker(private val program: Program,
                         checkValueTypeAndRange(decl.datatype, decl.value as NumericLiteralValue)
                     }
                     else -> {
-                        err("var/const declaration needs a compile-time constant initializer value, or range, instead found: ${decl.value!!.javaClass.simpleName}")
-                        super.visit(decl)
-                        return
+                        if(decl.type==VarDeclType.CONST) {
+                            err("const declaration needs a compile-time constant initializer value, or range")
+                            super.visit(decl)
+                            return
+                        }
                     }
                 }
             }
             VarDeclType.MEMORY -> {
                 if(decl.arraysize!=null) {
-                    val arraySize = decl.arraysize!!.size() ?: 1
+                    val arraySize = decl.arraysize!!.constIndex() ?: 1
                     when(decl.datatype) {
                         DataType.ARRAY_B, DataType.ARRAY_UB ->
                             if(arraySize > 256)
@@ -577,6 +609,26 @@ internal class AstChecker(private val program: Program,
             }
         }
 
+        // array length limits
+        if(decl.isArray) {
+            val length = decl.arraysize!!.constIndex() ?: 1
+            when (decl.datatype) {
+                DataType.STR, DataType.ARRAY_UB, DataType.ARRAY_B -> {
+                    if(length==0 || length>256)
+                        err("string and byte array length must be 1-256")
+                }
+                DataType.ARRAY_UW, DataType.ARRAY_W -> {
+                    if(length==0 || length>128)
+                        err("word array length must be 1-128")
+                }
+                DataType.ARRAY_F -> {
+                    if(length==0 || length>51)
+                        err("float array length must be 1-51")
+                }
+                else -> {}
+            }
+        }
+
         super.visit(decl)
     }
 
@@ -660,6 +712,14 @@ internal class AstChecker(private val program: Program,
                 else if(directive.args.map{it.name in setOf("enable_floats", "force_output")}.any { !it })
                     err("invalid option directive argument(s)")
             }
+            "%target" -> {
+                if(directive.parent !is Block && directive.parent !is Module)
+                    err("this directive may only occur in a block or at module level")
+                if(directive.args.size != 1)
+                    err("directive requires one argument")
+                if(directive.args.single().name !in setOf(C64Target.name, Cx16Target.name))
+                    err("invalid compilation target")
+            }
             else -> throw SyntaxError("invalid directive ${directive.directive}", directive.position)
         }
         super.visit(directive)
@@ -691,12 +751,20 @@ internal class AstChecker(private val program: Program,
     }
 
     override fun visit(expr: PrefixExpression) {
+        val dt = expr.inferType(program).typeOrElse(DataType.STRUCT)
         if(expr.operator=="-") {
-            val dt = expr.inferType(program).typeOrElse(DataType.STRUCT)
             if (dt != DataType.BYTE && dt != DataType.WORD && dt != DataType.FLOAT) {
                 errors.err("can only take negative of a signed number type", expr.position)
             }
         }
+        else if(expr.operator == "not") {
+            if(dt !in IntegerDatatypes)
+                errors.err("can only use boolean not on integer types", expr.position)
+        }
+        else if(expr.operator == "~") {
+            if(dt !in IntegerDatatypes)
+                errors.err("can only use bitwise invert on integer types", expr.position)
+        }
         super.visit(expr)
     }
 
@@ -738,12 +806,6 @@ internal class AstChecker(private val program: Program,
                 if(leftDt !in IntegerDatatypes || rightDt !in IntegerDatatypes)
                     errors.err("bitwise operator can only be used on integer operands", expr.right.position)
             }
-            "<<", ">>" -> {
-                // for now, bit-shifts can only shift by a constant number
-                val constRight = expr.right.constValue(program)
-                if(constRight==null)
-                    errors.err("bit-shift can only be done by a constant number (for now)", expr.right.position)
-            }
         }
 
         if(leftDt !in NumericDatatypes)
@@ -810,6 +872,10 @@ internal class AstChecker(private val program: Program,
                 errors.warn("sgn() of unsigned type is always 0 or 1, this is perhaps not what was intended", functionCall.args.first().position)
         }
 
+        val error = VerifyFunctionArgTypes.checkTypes(functionCall, functionCall.definingScope(), program)
+        if(error!=null)
+            errors.err(error, functionCall.args.first().position)
+
         super.visit(functionCall)
     }
 
@@ -832,12 +898,18 @@ internal class AstChecker(private val program: Program,
             }
         }
 
-        if(functionCallStatement.target.nameInSource.last() in setOf("lsl", "lsr", "rol", "ror", "rol2", "ror2", "swap", "sort", "reverse")) {
+        if(functionCallStatement.target.nameInSource.last() in setOf("rol", "ror", "rol2", "ror2", "swap", "sort", "reverse")) {
             // in-place modification, can't be done on literals
             if(functionCallStatement.args.any { it !is IdentifierReference && it !is ArrayIndexedExpression && it !is DirectMemoryRead }) {
                 errors.err("invalid argument to a in-place modifying function", functionCallStatement.args.first().position)
             }
         }
+
+        val error = VerifyFunctionArgTypes.checkTypes(functionCallStatement, functionCallStatement.definingScope(), program)
+        if(error!=null) {
+            errors.err(error, functionCallStatement.args.firstOrNull()?.position ?: functionCallStatement.position)
+        }
+
         super.visit(functionCallStatement)
     }
 
@@ -846,79 +918,35 @@ internal class AstChecker(private val program: Program,
             errors.err("cannot use arguments when calling a label", position)
 
         if(target is BuiltinFunctionStatementPlaceholder) {
-            // it's a call to a builtin function.
-            val func = BuiltinFunctions.getValue(target.name)
-            if(args.size!=func.parameters.size)
-                errors.err("invalid number of arguments", position)
-            else {
-                val paramTypesForAddressOf = PassByReferenceDatatypes + DataType.UWORD
-                for (arg in args.withIndex().zip(func.parameters)) {
-                    val argDt=arg.first.value.inferType(program)
-                    if (argDt.isKnown
-                            && !(argDt.typeOrElse(DataType.STRUCT) isAssignableTo arg.second.possibleDatatypes)
-                            && (argDt.typeOrElse(DataType.STRUCT) != DataType.UWORD || arg.second.possibleDatatypes.intersect(paramTypesForAddressOf).isEmpty())) {
-                        errors.err("builtin function '${target.name}' argument ${arg.first.index + 1} has invalid type $argDt, expected ${arg.second.possibleDatatypes}", position)
-                    }
+            if(target.name=="swap") {
+                // swap() is a bit weird because this one is translated into a operations directly, instead of being a function call
+                val dt1 = args[0].inferType(program)
+                val dt2 = args[1].inferType(program)
+                if (dt1 != dt2)
+                    errors.err("swap requires 2 args of identical type", position)
+                else if (args[0].constValue(program) != null || args[1].constValue(program) != null)
+                    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)
+                    errors.err("swap requires args of numerical type", position)
+            }
+            else if(target.name=="all" || target.name=="any") {
+                if((args[0] as? AddressOf)?.identifier?.targetVarDecl(program.namespace)?.datatype == DataType.STR) {
+                    errors.err("any/all on a string is useless (is always true unless the string is empty)", position)
                 }
-                if(target.name=="swap") {
-                    // swap() is a bit weird because this one is translated into a operations directly, instead of being a function call
-                    val dt1 = args[0].inferType(program)
-                    val dt2 = args[1].inferType(program)
-                    if (dt1 != dt2)
-                        errors.err("swap requires 2 args of identical type", position)
-                    else if (args[0].constValue(program) != null || args[1].constValue(program) != null)
-                        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)
-                        errors.err("swap requires args of numerical type", position)
-                }
-                else if(target.name=="all" || target.name=="any") {
-                    if((args[0] as? AddressOf)?.identifier?.targetVarDecl(program.namespace)?.datatype == DataType.STR) {
-                        errors.err("any/all on a string is useless (is always true unless the string is empty)", position)
-                    }
-                    if(args[0].inferType(program).typeOrElse(DataType.STR) == DataType.STR) {
-                        errors.err("any/all on a string is useless (is always true unless the string is empty)", position)
-                    }
+                if(args[0].inferType(program).typeOrElse(DataType.STR) == DataType.STR) {
+                    errors.err("any/all on a string is useless (is always true unless the string is empty)", position)
                 }
             }
         } else if(target is Subroutine) {
             if(target.regXasResult())
                 errors.warn("subroutine call return value in X register is discarded and replaced by 0", position)
-            if(args.size!=target.parameters.size)
-                errors.err("invalid number of arguments", position)
-            else {
+            if(target.isAsmSubroutine) {
                 for (arg in args.withIndex().zip(target.parameters)) {
                     val argIDt = arg.first.value.inferType(program)
-                    if(!argIDt.isKnown) {
+                    if (!argIDt.isKnown)
                         return
-                    }
-                    val argDt=argIDt.typeOrElse(DataType.STRUCT)
-                    if(!(argDt isAssignableTo arg.second.type)) {
-                        // for asm subroutines having STR param it's okay to provide a UWORD (address value)
-                        if(!(target.isAsmSubroutine && arg.second.type == DataType.STR && argDt == DataType.UWORD))
-                            errors.err("subroutine '${target.name}' argument ${arg.first.index + 1} has invalid type $argDt, expected ${arg.second.type}", position)
-                    }
-
-                    if(target.isAsmSubroutine) {
-                        if (target.asmParameterRegisters[arg.first.index].registerOrPair in setOf(RegisterOrPair.AX, RegisterOrPair.XY, RegisterOrPair.X)) {
-                            if (arg.first.value !is NumericLiteralValue && arg.first.value !is IdentifierReference)
-                                errors.warn("calling a subroutine that expects X as a parameter is problematic. If you see a compiler error/crash about this later, try to change this call", position)
-                        }
-
-                        // check if the argument types match the register(pairs)
-                        val asmParamReg = target.asmParameterRegisters[arg.first.index]
-                        if(asmParamReg.statusflag!=null) {
-                            if(argDt !in ByteDatatypes)
-                                errors.err("subroutine '${target.name}' argument ${arg.first.index + 1} must be byte type for statusflag", position)
-                        } else if(asmParamReg.registerOrPair in setOf(RegisterOrPair.A, RegisterOrPair.X, RegisterOrPair.Y)) {
-                            if(argDt !in ByteDatatypes)
-                                errors.err("subroutine '${target.name}' argument ${arg.first.index + 1} must be byte type for single register", position)
-                        } else if(asmParamReg.registerOrPair in setOf(RegisterOrPair.AX, RegisterOrPair.AY, RegisterOrPair.XY)) {
-                            if(argDt !in WordDatatypes + IterableDatatypes)
-                                errors.err("subroutine '${target.name}' argument ${arg.first.index + 1} must be word type for register pair", position)
-                        }
-                    }
                 }
             }
         }
@@ -958,7 +986,7 @@ internal class AstChecker(private val program: Program,
         if(target is VarDecl) {
             if(target.datatype !in IterableDatatypes)
                 errors.err("indexing requires an iterable variable", arrayIndexedExpression.position)
-            val arraysize = target.arraysize?.size()
+            val arraysize = target.arraysize?.constIndex()
             if(arraysize!=null) {
                 // check out of bounds
                 val index = (arrayIndexedExpression.arrayspec.index as? NumericLiteralValue)?.number?.toInt()
@@ -1039,35 +1067,14 @@ internal class AstChecker(private val program: Program,
         }
     }
 
-    override fun visit(scope: AnonymousScope) {
-        visitStatements(scope.statements)
-    }
-
-    private fun visitStatements(statements: List<Statement>) {
-        for((index, stmt) in statements.withIndex()) {
-            if(index < statements.lastIndex && statements[index+1] !is Subroutine) {
-                when {
-                    stmt is FunctionCallStatement && stmt.target.nameInSource.last() == "exit" -> {
-                        errors.warn("unreachable code, preceding exit call will never return", statements[index + 1].position)
-                    }
-                    stmt is Return && statements[index + 1] !is Subroutine -> {
-                        errors.warn("unreachable code, preceding return statement", statements[index + 1].position)
-                    }
-                    stmt is Jump && statements[index + 1] !is Subroutine -> {
-                        errors.warn("unreachable code, preceding jump statement", statements[index + 1].position)
-                    }
-                }
-            }
-
-            stmt.accept(this)
-        }
-    }
-
     private fun checkFunctionOrLabelExists(target: IdentifierReference, statement: Statement): Statement? {
         val targetStatement = target.targetStatement(program.namespace)
         if(targetStatement is Label || targetStatement is Subroutine || targetStatement is BuiltinFunctionStatementPlaceholder)
             return targetStatement
-        errors.err("undefined function or subroutine: ${target.nameInSource.joinToString(".")}", statement.position)
+        else if(targetStatement==null)
+            errors.err("undefined function or subroutine: ${target.nameInSource.joinToString(".")}", statement.position)
+        else
+            errors.err("cannot call that: ${target.nameInSource.joinToString(".")}", statement.position)
         return null
     }
 
@@ -1100,7 +1107,7 @@ internal class AstChecker(private val program: Program,
                 if(value.type.istype(targetDt)) {
                     if(!checkArrayValues(value, targetDt))
                         return false
-                    val arraySpecSize = arrayspec.size()
+                    val arraySpecSize = arrayspec.constIndex()
                     val arraySize = value.value.size
                     if(arraySpecSize!=null && arraySpecSize>0) {
                         if(arraySpecSize<1 || arraySpecSize>256)
@@ -1122,7 +1129,7 @@ internal class AstChecker(private val program: Program,
                 if(value.type.istype(targetDt)) {
                     if(!checkArrayValues(value, targetDt))
                         return false
-                    val arraySpecSize = arrayspec.size()
+                    val arraySpecSize = arrayspec.constIndex()
                     val arraySize = value.value.size
                     if(arraySpecSize!=null && arraySpecSize>0) {
                         if(arraySpecSize<1 || arraySpecSize>128)
@@ -1145,7 +1152,7 @@ internal class AstChecker(private val program: Program,
                     if(!checkArrayValues(value, targetDt))
                         return false
                     val arraySize = value.value.size
-                    val arraySpecSize = arrayspec.size()
+                    val arraySpecSize = arrayspec.constIndex()
                     if(arraySpecSize!=null && arraySpecSize>0) {
                         if(arraySpecSize < 1 || arraySpecSize>51)
                             return err("float array length must be 1-51")
@@ -1160,7 +1167,7 @@ internal class AstChecker(private val program: Program,
 
                     // check if the floating point values are all within range
                     val doubles = value.value.map {it.constValue(program)?.number!!.toDouble()}.toDoubleArray()
-                    if(doubles.any { it < CompilationTarget.machine.FLOAT_MAX_NEGATIVE || it > CompilationTarget.machine.FLOAT_MAX_POSITIVE })
+                    if(doubles.any { it < CompilationTarget.instance.machine.FLOAT_MAX_NEGATIVE || it > CompilationTarget.instance.machine.FLOAT_MAX_POSITIVE })
                         return err("floating point value overflow")
                     return true
                 }
@@ -1237,7 +1244,11 @@ internal class AstChecker(private val program: Program,
                 is AddressOf -> it.identifier.heapId(program.namespace)
                 is TypecastExpression -> {
                     val constVal = it.expression.constValue(program)
-                    constVal?.cast(it.type)?.number?.toInt() ?: -9999999
+                    val cast = constVal?.cast(it.type)
+                    if(cast==null || !cast.isValid)
+                        -9999999
+                    else
+                        cast.valueOrZero().number.toInt()
                 }
                 else -> -9999999
             }

compiler/src/prog8/ast/processing/AstIdentifiersChecker.kt

@@ -22,6 +22,9 @@ internal class AstIdentifiersChecker(private val program: Program, private val e
     }
 
     override fun visit(block: Block) {
+        if(block.name in CompilationTarget.instance.machine.opcodeNames)
+            errors.err("can't use a cpu opcode name as a symbol: '${block.name}'", block.position)
+
         val existing = blocks[block.name]
         if(existing!=null)
             nameError(block.name, block.position, existing)
@@ -37,7 +40,7 @@ internal class AstIdentifiersChecker(private val program: Program, private val e
         if(decl.name in BuiltinFunctions)
             errors.err("builtin function cannot be redefined", decl.position)
 
-        if(decl.name in CompilationTarget.machine.opcodeNames)
+        if(decl.name in CompilationTarget.instance.machine.opcodeNames)
             errors.err("can't use a cpu opcode name as a symbol: '${decl.name}'", decl.position)
 
         if(decl.datatype==DataType.STRUCT) {
@@ -71,7 +74,7 @@ internal class AstIdentifiersChecker(private val program: Program, private val e
     }
 
     override fun visit(subroutine: Subroutine) {
-        if(subroutine.name in CompilationTarget.machine.opcodeNames) {
+        if(subroutine.name in CompilationTarget.instance.machine.opcodeNames) {
             errors.err("can't use a cpu opcode name as a symbol: '${subroutine.name}'", subroutine.position)
         } else if(subroutine.name in BuiltinFunctions) {
             // the builtin functions can't be redefined
@@ -116,7 +119,7 @@ internal class AstIdentifiersChecker(private val program: Program, private val e
     }
 
     override fun visit(label: Label) {
-        if(label.name in CompilationTarget.machine.opcodeNames)
+        if(label.name in CompilationTarget.instance.machine.opcodeNames)
             errors.err("can't use a cpu opcode name as a symbol: '${label.name}'", label.position)
 
         if(label.name in BuiltinFunctions) {

compiler/src/prog8/ast/processing/AstVariousTransforms.kt

@@ -12,6 +12,7 @@ internal class AstVariousTransforms(private val program: Program) : AstWalker()
 
     override fun after(functionCallStatement: FunctionCallStatement, parent: Node): Iterable<IAstModification> {
         if(functionCallStatement.target.nameInSource == listOf("swap")) {
+            // TODO don't replace swap(), let the code generator figure this all out
             // if x and y are both just identifiers, do not rewrite (there should be asm generation for that)
             // otherwise:
             // rewrite swap(x,y) as follows:
@@ -26,19 +27,16 @@ internal class AstVariousTransforms(private val program: Program) : AstWalker()
                 val tempvar = IdentifierReference(listOf(tempname), first.position)
                 val assignTemp = Assignment(
                         AssignTarget(tempvar, null, null, first.position),
-                        null,
                         first,
                         first.position
                 )
                 val assignFirst = Assignment(
                         AssignTarget.fromExpr(first),
-                        null,
                         second,
                         first.position
                 )
                 val assignSecond = Assignment(
                         AssignTarget.fromExpr(second),
-                        null,
                         tempvar,
                         first.position
                 )
@@ -50,18 +48,6 @@ internal class AstVariousTransforms(private val program: Program) : AstWalker()
         return noModifications
     }
 
-    override fun before(functionCall: FunctionCall, parent: Node): Iterable<IAstModification> {
-        if(functionCall.target.nameInSource.size==1 && functionCall.target.nameInSource[0]=="lsb") {
-            // lsb(...) is just an alias for type cast to ubyte, so replace with "... as ubyte"
-            val typecast = TypecastExpression(functionCall.args.single(), DataType.UBYTE, false, functionCall.position)
-            return listOf(IAstModification.ReplaceNode(
-                    functionCall, typecast, parent
-            ))
-        }
-
-        return noModifications
-    }
-
     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.

compiler/src/prog8/ast/processing/AstWalker.kt

@@ -61,6 +61,18 @@ interface IAstModification {
         }
     }
 
+    class InsertBefore(val before: Statement, val stmt: Statement, val parent: Node) : IAstModification {
+        override fun perform() {
+            if(parent is INameScope) {
+                val idx = parent.statements.indexOfFirst { it===before }
+                parent.statements.add(idx, stmt)
+                stmt.linkParents(parent)
+            } else {
+                throw FatalAstException("parent of an insert modification is not an INameScope")
+            }
+        }
+    }
+
     class ReplaceNode(val node: Node, val replacement: Node, val parent: Node) : IAstModification {
         override fun perform() {
             parent.replaceChildNode(node, replacement)
@@ -88,7 +100,6 @@ abstract class AstWalker {
     open fun before(branchStatement: BranchStatement, parent: Node): Iterable<IAstModification> = emptyList()
     open fun before(breakStmt: Break, parent: Node): Iterable<IAstModification> = emptyList()
     open fun before(builtinFunctionStatementPlaceholder: BuiltinFunctionStatementPlaceholder, parent: Node): Iterable<IAstModification> = emptyList()
-    open fun before(contStmt: Continue, 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()
@@ -130,7 +141,6 @@ abstract class AstWalker {
     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(contStmt: Continue, 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()
@@ -309,11 +319,6 @@ abstract class AstWalker {
         track(after(postIncrDecr, parent), postIncrDecr, parent)
     }
 
-    fun visit(contStmt: Continue, parent: Node) {
-        track(before(contStmt, parent), contStmt, parent)
-        track(after(contStmt, parent), contStmt, parent)
-    }
-
     fun visit(breakStmt: Break, parent: Node) {
         track(before(breakStmt, parent), breakStmt, parent)
         track(after(breakStmt, parent), breakStmt, parent)

compiler/src/prog8/ast/processing/IAstVisitor.kt

@@ -95,9 +95,6 @@ interface IAstVisitor {
         postIncrDecr.target.accept(this)
     }
 
-    fun visit(contStmt: Continue) {
-    }
-
     fun visit(breakStmt: Break) {
     }
 

compiler/src/prog8/ast/processing/StatementReorderer.kt

@@ -14,8 +14,8 @@ internal class StatementReorderer(val program: Program) : AstWalker() {
     // - in every scope, most directives and vardecls are moved to the top.
     // - 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) augmented assignment is turned into regular assignment.
     // - (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).
 
@@ -71,23 +71,6 @@ internal class StatementReorderer(val program: Program) : AstWalker() {
         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
-                decl.value = null
-                val target = AssignTarget(IdentifierReference(listOf(decl.name), decl.position), null, null, decl.position)
-                val assign = Assignment(target, null, declValue, decl.position)
-                return listOf(
-                        IAstModification.ReplaceNode(decl, assign, parent),
-                        IAstModification.InsertFirst(decl, decl.definingScope() as Node)
-                )
-            }
-        }
-        return noModifications
-    }
 
     override fun after(whenStatement: WhenStatement, parent: Node): Iterable<IAstModification> {
         val choices = whenStatement.choiceValues(program).sortedBy {
@@ -99,10 +82,6 @@ internal class StatementReorderer(val program: Program) : AstWalker() {
     }
 
     override fun before(assignment: Assignment, parent: Node): Iterable<IAstModification> {
-        if(assignment.aug_op!=null) {
-            return listOf(IAstModification.ReplaceNode(assignment, assignment.asDesugaredNonaugmented(), parent))
-        }
-
         val valueType = assignment.value.inferType(program)
         val targetType = assignment.target.inferType(program, assignment)
         if(valueType.istype(DataType.STRUCT) && targetType.istype(DataType.STRUCT)) {
@@ -122,6 +101,55 @@ internal class StatementReorderer(val program: Program) : AstWalker() {
         return noModifications
     }
 
+    override fun after(assignment: Assignment, parent: Node): Iterable<IAstModification> {
+        // rewrite in-place assignment expressions a bit so that the assignment target usually is the leftmost operand
+        val binExpr = assignment.value as? BinaryExpression
+        if(binExpr!=null) {
+            if(binExpr.left isSameAs assignment.target) {
+                // A = A <operator> 5, unchanged
+                return noModifications
+            }
+
+            if(binExpr.operator in associativeOperators) {
+                if (binExpr.right isSameAs assignment.target) {
+                    // A = v <associative-operator> A  ==>  A = A <associative-operator> v
+                    return listOf(IAstModification.SwapOperands(binExpr))
+                }
+
+                val leftBinExpr = binExpr.left as? BinaryExpression
+                if(leftBinExpr?.operator == binExpr.operator) {
+                    return if(leftBinExpr.left isSameAs assignment.target) {
+                        // A = (A <associative-operator> x) <same-operator> y ==> A = A <associative-operator> (x <same-operator> y)
+                        val newRight = BinaryExpression(leftBinExpr.right, binExpr.operator, binExpr.right, binExpr.position)
+                        val newValue = BinaryExpression(leftBinExpr.left, binExpr.operator, newRight, binExpr.position)
+                        listOf(IAstModification.ReplaceNode(binExpr, newValue, assignment))
+                    } else {
+                        // A = (x <associative-operator> A) <same-operator> y ==> A = A <associative-operator> (x <same-operator> y)
+                        val newRight = BinaryExpression(leftBinExpr.left, binExpr.operator, binExpr.right, binExpr.position)
+                        val newValue = BinaryExpression(leftBinExpr.right, binExpr.operator, newRight, binExpr.position)
+                        listOf(IAstModification.ReplaceNode(binExpr, newValue, assignment))
+                    }
+                }
+                val rightBinExpr = binExpr.right as? BinaryExpression
+                if(rightBinExpr?.operator == binExpr.operator) {
+                    return if(rightBinExpr.left isSameAs assignment.target) {
+                        // A = x <associative-operator> (A <same-operator> y) ==> A = A <associative-operator> (x <same-operator> y)
+                        val newRight = BinaryExpression(binExpr.left, binExpr.operator, rightBinExpr.right, binExpr.position)
+                        val newValue = BinaryExpression(rightBinExpr.left, binExpr.operator, newRight, binExpr.position)
+                        listOf(IAstModification.ReplaceNode(binExpr, newValue, assignment))
+                    } else {
+                        // A = x <associative-operator> (y <same-operator> A) ==> A = A <associative-operator> (x <same-operator> y)
+                        val newRight = BinaryExpression(binExpr.left, binExpr.operator, rightBinExpr.left, binExpr.position)
+                        val newValue = BinaryExpression(rightBinExpr.right, binExpr.operator, newRight, binExpr.position)
+                        listOf(IAstModification.ReplaceNode(binExpr, newValue, assignment))
+                    }
+                }
+            }
+        }
+
+        return noModifications
+    }
+
     private fun flattenStructAssignmentFromStructLiteral(structAssignment: Assignment, program: Program): List<Assignment> {
         val identifier = structAssignment.target.identifier!!
         val identifierName = identifier.nameInSource.single()
@@ -137,7 +165,7 @@ internal class StatementReorderer(val program: Program) : AstWalker() {
             val mangled = mangledStructMemberName(identifierName, targetDecl.name)
             val idref = IdentifierReference(listOf(mangled), structAssignment.position)
             val assign = Assignment(AssignTarget(idref, null, null, structAssignment.position),
-                    null, sourceValue, sourceValue.position)
+                    sourceValue, sourceValue.position)
             assign.linkParents(structAssignment)
             assign
         }
@@ -168,8 +196,7 @@ internal class StatementReorderer(val program: Program) : AstWalker() {
                     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),
-                            null, sourceIdref, member.second.position)
+                    val assign = Assignment(AssignTarget(idref, null, null, structAssignment.position), sourceIdref, member.second.position)
                     assign.linkParents(structAssignment)
                     assign
                 }

compiler/src/prog8/ast/processing/TypecastsAdder.kt

@@ -18,6 +18,21 @@ class TypecastsAdder(val program: Program, val errors: ErrorReporter) : AstWalke
 
     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) {
+            val valueDt = declValue.inferType(program)
+            if(!valueDt.istype(decl.datatype)) {
+                return listOf(IAstModification.ReplaceNode(
+                        declValue,
+                        TypecastExpression(declValue, decl.datatype, true, declValue.position),
+                        decl
+                ))
+            }
+        }
+        return noModifications
+    }
+
     override fun after(expr: BinaryExpression, parent: Node): Iterable<IAstModification> {
         val leftDt = expr.left.inferType(program)
         val rightDt = expr.right.inferType(program)
@@ -51,8 +66,13 @@ class TypecastsAdder(val program: Program, val errors: ErrorReporter) : AstWalke
                             TypecastExpression(assignment.value, targettype, true, assignment.value.position),
                             assignment))
                 } else {
-                    fun castLiteral(cvalue: NumericLiteralValue): List<IAstModification.ReplaceNode> =
-                        listOf(IAstModification.ReplaceNode(cvalue, cvalue.cast(targettype), cvalue.parent))
+                    fun castLiteral(cvalue: NumericLiteralValue): List<IAstModification.ReplaceNode> {
+                        val cast = cvalue.cast(targettype)
+                        return if(cast.isValid)
+                            listOf(IAstModification.ReplaceNode(cvalue, cast.valueOrZero(), cvalue.parent))
+                        else
+                            emptyList()
+                    }
                     val cvalue = assignment.value.constValue(program)
                     if(cvalue!=null) {
                         val number = cvalue.number.toDouble()
@@ -109,15 +129,12 @@ class TypecastsAdder(val program: Program, val errors: ErrorReporter) : AstWalke
                                         AddressOf(arg.second.value as IdentifierReference, arg.second.value.position),
                                         call as Node)
                             } else if(arg.second.value is NumericLiteralValue) {
-                                try {
-                                    val castedValue = (arg.second.value as NumericLiteralValue).cast(requiredType)
+                                val cast = (arg.second.value as NumericLiteralValue).cast(requiredType)
+                                if(cast.isValid)
                                     modifications += IAstModification.ReplaceNode(
                                             call.args[arg.second.index],
-                                            castedValue,
+                                            cast.valueOrZero(),
                                             call as Node)
-                                } catch (x: ExpressionError) {
-                                    // no cast possible
-                                }
                             }
                         }
                     }
@@ -137,13 +154,13 @@ class TypecastsAdder(val program: Program, val errors: ErrorReporter) : AstWalke
                                         call.args[arg.second.index],
                                         TypecastExpression(arg.second.value, possibleType, true, arg.second.value.position),
                                         call as Node)
+                                break
                             }
                         }
                     }
                 }
             }
-            null -> { }
-            else -> throw FatalAstException("call to something weird $sub   ${call.target}")
+            else -> { }
         }
 
         return modifications
@@ -152,7 +169,7 @@ class TypecastsAdder(val program: Program, val errors: ErrorReporter) : AstWalke
     override fun after(typecast: TypecastExpression, parent: Node): Iterable<IAstModification> {
         // warn about any implicit type casts to Float, because that may not be intended
         if(typecast.implicit && typecast.type in setOf(DataType.FLOAT, DataType.ARRAY_F)) {
-            errors.warn("byte or word value implicitly converted to float. Suggestion: use explicit cast as float, a float number, or revert to integer arithmetic", typecast.position)
+            errors.warn("integer implicitly converted to float. Suggestion: use float literals, add an explicit cast, or revert to integer arithmetic", typecast.position)
         }
         return noModifications
     }
@@ -161,7 +178,7 @@ class TypecastsAdder(val program: Program, val errors: ErrorReporter) : AstWalke
         // make sure the memory address is an uword
         val dt = memread.addressExpression.inferType(program)
         if(dt.isKnown && dt.typeOrElse(DataType.UWORD)!=DataType.UWORD) {
-            val typecast = (memread.addressExpression as? NumericLiteralValue)?.cast(DataType.UWORD)
+            val typecast = (memread.addressExpression as? NumericLiteralValue)?.cast(DataType.UWORD)?.valueOrZero()
                     ?: TypecastExpression(memread.addressExpression, DataType.UWORD, true, memread.addressExpression.position)
             return listOf(IAstModification.ReplaceNode(memread.addressExpression, typecast, memread))
         }
@@ -172,7 +189,7 @@ class TypecastsAdder(val program: Program, val errors: ErrorReporter) : AstWalke
         // make sure the memory address is an uword
         val dt = memwrite.addressExpression.inferType(program)
         if(dt.isKnown && dt.typeOrElse(DataType.UWORD)!=DataType.UWORD) {
-            val typecast = (memwrite.addressExpression as? NumericLiteralValue)?.cast(DataType.UWORD)
+            val typecast = (memwrite.addressExpression as? NumericLiteralValue)?.cast(DataType.UWORD)?.valueOrZero()
                     ?: TypecastExpression(memwrite.addressExpression, DataType.UWORD, true, memwrite.addressExpression.position)
             return listOf(IAstModification.ReplaceNode(memwrite.addressExpression, typecast, memwrite))
         }
@@ -189,7 +206,9 @@ class TypecastsAdder(val program: Program, val errors: ErrorReporter) : AstWalke
                 if (returnValue.inferType(program).istype(subReturnType))
                     return noModifications
                 if (returnValue is NumericLiteralValue) {
-                    returnStmt.value = returnValue.cast(subroutine.returntypes.single())
+                    val cast = returnValue.cast(subroutine.returntypes.single())
+                    if(cast.isValid)
+                        returnStmt.value = cast.valueOrZero()
                 } else {
                     return listOf(IAstModification.ReplaceNode(
                             returnValue,

compiler/src/prog8/ast/processing/VariousCleanups.kt

@@ -35,7 +35,8 @@ internal class VariousCleanups: AstWalker() {
     override fun before(typecast: TypecastExpression, parent: Node): Iterable<IAstModification> {
         if(typecast.expression is NumericLiteralValue) {
             val value = (typecast.expression as NumericLiteralValue).cast(typecast.type)
-            return listOf(IAstModification.ReplaceNode(typecast, value, parent))
+            if(value.isValid)
+                return listOf(IAstModification.ReplaceNode(typecast, value.valueOrZero(), parent))
         }
 
         return noModifications

compiler/src/prog8/ast/processing/VerifyFunctionArgTypes.kt

@@ -13,30 +13,49 @@ import prog8.functions.BuiltinFunctions
 
 class VerifyFunctionArgTypes(val program: Program) : IAstVisitor {
 
-    override fun visit(functionCall: FunctionCall)
-            = checkTypes(functionCall as IFunctionCall, functionCall.definingScope())
+    override fun visit(functionCall: FunctionCall) {
+        val error = checkTypes(functionCall as IFunctionCall, functionCall.definingScope(), program)
+        if(error!=null)
+            throw CompilerException(error)
+    }
 
-    override fun visit(functionCallStatement: FunctionCallStatement)
-            = checkTypes(functionCallStatement as IFunctionCall, functionCallStatement.definingScope())
+    override fun visit(functionCallStatement: FunctionCallStatement) {
+        val error = checkTypes(functionCallStatement as IFunctionCall, functionCallStatement.definingScope(), program)
+        if (error!=null)
+            throw CompilerException(error)
+    }
 
-    private fun checkTypes(call: IFunctionCall, scope: INameScope) {
-        val argtypes = call.args.map { it.inferType(program).typeOrElse(DataType.STRUCT) }
-        val target = call.target.targetStatement(scope)
-        when(target) {
-            is Subroutine -> {
+    companion object {
+        fun checkTypes(call: IFunctionCall, scope: INameScope, program: Program): String? {
+            val argtypes = call.args.map { it.inferType(program).typeOrElse(DataType.STRUCT) }
+            val target = call.target.targetStatement(scope)
+            if (target is Subroutine) {
+                // asmsub types are not checked specifically at this time
+                if(call.args.size != target.parameters.size)
+                    return "invalid number of arguments"
                 val paramtypes = target.parameters.map { it.type }
-                if(argtypes!=paramtypes)
-                    throw CompilerException("parameter type mismatch $call")
-            }
-            is BuiltinFunctionStatementPlaceholder -> {
-                val func = BuiltinFunctions.getValue(target.name)
-                val paramtypes = func.parameters.map { it.possibleDatatypes }
-                for(x in argtypes.zip(paramtypes)) {
-                    if(x.first !in x.second)
-                        throw CompilerException("parameter type mismatch $call")
+                val mismatch = argtypes.zip(paramtypes).indexOfFirst { it.first != it.second}
+                if(mismatch>=0) {
+                    val actual = argtypes[mismatch].toString()
+                    val expected = paramtypes[mismatch].toString()
+                    return "argument ${mismatch + 1} type mismatch, was: $actual expected: $expected"
                 }
             }
-            else -> {}
+            else if (target is BuiltinFunctionStatementPlaceholder) {
+                val func = BuiltinFunctions.getValue(target.name)
+                if(call.args.size != func.parameters.size)
+                    return "invalid number of arguments"
+                val paramtypes = func.parameters.map { it.possibleDatatypes }
+                for (x in argtypes.zip(paramtypes).withIndex()) {
+                    if (x.value.first !in x.value.second) {
+                        val actual = x.value.first.toString()
+                        val expected = x.value.second.toString()
+                        return "argument ${x.index + 1} type mismatch, was: $actual expected: $expected"
+                    }
+                }
+            }
+
+            return null
         }
     }
 }

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

@@ -139,27 +139,6 @@ open class Return(var value: Expression?, override val position: Position) : Sta
     }
 }
 
-class ReturnFromIrq(override val position: Position) : Return(null, position) {
-    override fun accept(visitor: IAstVisitor) = visitor.visit(this)
-
-    override fun toString(): String {
-        return "ReturnFromIrq(pos=$position)"
-    }
-    override fun replaceChildNode(node: Node, replacement: Node) = throw FatalAstException("can't replace here")
-}
-
-class Continue(override val position: Position) : Statement() {
-    override lateinit var parent: Node
-
-    override fun linkParents(parent: Node) {
-        this.parent=parent
-    }
-
-    override fun replaceChildNode(node: Node, replacement: Node) = throw FatalAstException("can't replace here")
-    override fun accept(visitor: IAstVisitor) = visitor.visit(this)
-    override fun accept(visitor: AstWalker, parent: Node) = visitor.visit(this, parent)
-}
-
 class Break(override val position: Position) : Statement() {
     override lateinit var parent: Node
 
@@ -282,8 +261,8 @@ open class VarDecl(val type: VarDeclType,
                     member.isArray,
                     true,
                     member.position
-            ) as Statement
-        }.toMutableList()
+            )
+        }.toMutableList<Statement>()
         structHasBeenFlattened = true
         return result
     }
@@ -291,7 +270,7 @@ open class VarDecl(val type: VarDeclType,
 
 // a vardecl used only for subroutine parameters
 class ParameterVarDecl(name: String, declaredDatatype: DataType, position: Position)
-    : VarDecl(VarDeclType.VAR, declaredDatatype, ZeropageWish.NOT_IN_ZEROPAGE, null, name, null, null, false, true, position)
+    : VarDecl(VarDeclType.VAR, declaredDatatype, ZeropageWish.DONTCARE, null, name, null, null, false, true, position)
 
 
 class ArrayIndex(var index: Expression, override val position: Position) : Node {
@@ -321,10 +300,10 @@ class ArrayIndex(var index: Expression, override val position: Position) : Node
         return("ArrayIndex($index, pos=$position)")
     }
 
-    fun size() = (index as? NumericLiteralValue)?.number?.toInt()
+    fun constIndex() = (index as? NumericLiteralValue)?.number?.toInt()
 }
 
-open class Assignment(var target: AssignTarget, var aug_op : String?, var value: Expression, override val position: Position) : Statement() {
+open class Assignment(var target: AssignTarget, var value: Expression, override val position: Position) : Statement() {
     override lateinit var parent: Node
 
     override fun linkParents(parent: Node) {
@@ -346,31 +325,55 @@ open class Assignment(var target: AssignTarget, var aug_op : String?, var value:
     override fun accept(visitor: AstWalker, parent: Node) = visitor.visit(this, parent)
 
     override fun toString(): String {
-        return("Assignment(augop: $aug_op, target: $target, value: $value, pos=$position)")
+        return("Assignment(target: $target, value: $value, pos=$position)")
     }
 
-    fun asDesugaredNonaugmented(): Assignment {
-        val augmented = aug_op ?: return this
+    /**
+     * Is the assigment value an expression that references the assignment target itself?
+     * The expression can be a BinaryExpression, PrefixExpression or TypecastExpression (possibly with one sub-cast).
+     */
+    val isAugmentable: Boolean
+        get() {
+            val binExpr = value as? BinaryExpression
+            if(binExpr!=null) {
+                if(binExpr.left isSameAs target)
+                    return true  // A = A <operator> Something
 
-        val leftOperand: Expression =
-                when {
-                    target.identifier != null -> target.identifier!!
-                    target.arrayindexed != null -> target.arrayindexed!!
-                    target.memoryAddress != null -> DirectMemoryRead(target.memoryAddress!!.addressExpression, value.position)
-                    else -> throw FatalAstException("strange this")
+                if(binExpr.operator in associativeOperators) {
+                    if (binExpr.left !is BinaryExpression && binExpr.right isSameAs target)
+                        return true  // A = v <associative-operator> A
+
+                    val leftBinExpr = binExpr.left as? BinaryExpression
+                    if(leftBinExpr?.operator == binExpr.operator) {
+                        // one of these?
+                        // A = (A <associative-operator> x) <same-operator> y
+                        // A = (x <associative-operator> A) <same-operator> y
+                        // A = (x <associative-operator> y) <same-operator> A
+                        return leftBinExpr.left isSameAs target || leftBinExpr.right isSameAs target || binExpr.right isSameAs target
+                    }
+                    val rightBinExpr = binExpr.right as? BinaryExpression
+                    if(rightBinExpr?.operator == binExpr.operator) {
+                        // one of these?
+                        // A = y <associative-operator> (A <same-operator> x)
+                        // A = y <associative-operator> (x <same-operator> y)
+                        // A = A <associative-operator> (x <same-operator> y)
+                        return rightBinExpr.left isSameAs target || rightBinExpr.right isSameAs target || binExpr.left isSameAs target
+                    }
                 }
-
-        val assignment =
-            if(augmented=="setvalue") {
-                Assignment(target, null, value, position)
-            } else {
-                val expression = BinaryExpression(leftOperand, augmented.substringBeforeLast('='), value, position)
-                Assignment(target, null, expression, position)
             }
-        assignment.linkParents(parent)
 
-        return assignment
-    }
+            val prefixExpr = value as? PrefixExpression
+            if(prefixExpr!=null)
+                return prefixExpr.expression isSameAs target
+
+            val castExpr = value as? TypecastExpression
+            if(castExpr!=null) {
+                val subCast = castExpr.expression as? TypecastExpression
+                return if(subCast!=null) subCast.expression isSameAs target else castExpr.expression isSameAs target
+            }
+
+            return false
+        }
 }
 
 data class AssignTarget(var identifier: IdentifierReference?,
@@ -425,6 +428,15 @@ data class AssignTarget(var identifier: IdentifierReference?,
         return InferredTypes.unknown()
     }
 
+    fun toExpression(): Expression {
+        return when {
+            identifier!=null -> identifier!!
+            arrayindexed!=null -> arrayindexed!!
+            memoryAddress!=null -> DirectMemoryRead(memoryAddress.addressExpression, memoryAddress.position)
+            else -> throw FatalAstException("invalid assignmenttarget $this")
+        }
+    }
+
     infix fun isSameAs(value: Expression): Boolean {
         return when {
             this.memoryAddress!=null -> {
@@ -437,9 +449,9 @@ data class AssignTarget(var identifier: IdentifierReference?,
             this.identifier!=null -> value is IdentifierReference && value.nameInSource==identifier!!.nameInSource
             this.arrayindexed!=null -> value is ArrayIndexedExpression &&
                     value.identifier.nameInSource==arrayindexed!!.identifier.nameInSource &&
-                    value.arrayspec.size()!=null &&
-                    arrayindexed!!.arrayspec.size()!=null &&
-                    value.arrayspec.size()==arrayindexed!!.arrayspec.size()
+                    value.arrayspec.constIndex()!=null &&
+                    arrayindexed!!.arrayspec.constIndex()!=null &&
+                    value.arrayspec.constIndex()==arrayindexed!!.arrayspec.constIndex()
             else -> false
         }
     }
@@ -621,7 +633,6 @@ class Subroutine(override val name: String,
                  override var statements: MutableList<Statement>,
                  override val position: Position) : Statement(), INameScope {
 
-    var keepAlways: Boolean = false
     override lateinit var parent: Node
     val scopedname: String by lazy { makeScopedName(name) }
 
@@ -646,6 +657,7 @@ class Subroutine(override val name: String,
     }
 
     fun regXasResult() = asmReturnvaluesRegisters.any { it.registerOrPair in setOf(RegisterOrPair.X, RegisterOrPair.AX, RegisterOrPair.XY) }
+    fun regXasParam() = asmParameterRegisters.any { it.registerOrPair in setOf(RegisterOrPair.X, RegisterOrPair.AX, RegisterOrPair.XY) }
 
     fun amountOfRtsInAsm(): Int = statements
             .asSequence()

compiler/src/prog8/compiler/BeforeAsmGenerationAstChanger.kt

@@ -1,5 +1,6 @@
 package prog8.compiler
 
+import prog8.ast.IFunctionCall
 import prog8.ast.Node
 import prog8.ast.Program
 import prog8.ast.base.*
@@ -14,13 +15,32 @@ internal class BeforeAsmGenerationAstChanger(val program: Program, val errors: E
     private val noModifications = emptyList<IAstModification>()
 
     override fun after(decl: VarDecl, parent: Node): Iterable<IAstModification> {
-        if (decl.value == null && decl.type == VarDeclType.VAR && decl.datatype in NumericDatatypes) {
+        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.
             decl.value = decl.zeroElementValue()
         }
         return noModifications
     }
 
+    override fun after(assignment: Assignment, parent: Node): Iterable<IAstModification> {
+        // Try to replace A = B <operator> Something  by A= B, A = A <operator> Something
+        // this triggers the more efficent augmented assignment code generation more often.
+        if(!assignment.isAugmentable
+                && assignment.target.identifier != null
+                && assignment.target.isNotMemory(program.namespace)) {
+            val binExpr = assignment.value as? BinaryExpression
+            if(binExpr!=null && binExpr.operator !in comparisonOperators) {
+                if(binExpr.left !is BinaryExpression) {
+                    val assignLeft = Assignment(assignment.target, binExpr.left, assignment.position)
+                    return listOf(
+                            IAstModification.InsertBefore(assignment, assignLeft, parent),
+                            IAstModification.ReplaceNode(binExpr.left, assignment.target.toExpression(), binExpr))
+                }
+            }
+        }
+        return noModifications
+    }
+
     override fun after(scope: AnonymousScope, parent: Node): Iterable<IAstModification> {
         val decls = scope.statements.filterIsInstance<VarDecl>()
         val sub = scope.definingSubroutine()
@@ -35,12 +55,13 @@ internal class BeforeAsmGenerationAstChanger(val program: Program, val errors: E
                 }
             }
             if (!conflicts) {
-                val numericVarsWithValue = decls.filter { it.value != null && it.datatype in NumericDatatypes }
+                // move vardecls of the scope into the upper scope. Make sure the order remains the same!
+                val numericVarsWithValue = decls.filter { it.value != null && it.datatype in NumericDatatypes }.reversed()
                 return 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, null, initValue, it.position)
+                    val assign = Assignment(target, initValue, it.position)
                     initValue.parent = assign
                     IAstModification.InsertFirst(assign, scope)
                 } +  decls.map { IAstModification.ReplaceNode(it, NopStatement(it.position), scope) } +
@@ -89,7 +110,26 @@ internal class BeforeAsmGenerationAstChanger(val program: Program, val errors: E
                 return listOf(IAstModification.ReplaceNode(typecast, typecast.expression, parent))
             }
         }
-        else if(sourceDt in PassByReferenceDatatypes) {
+
+
+        // Note: for various reasons (most importantly, code simplicity), the code generator assumes/requires
+        // that the types of assignment values and their target are the same,
+        // and that the types of both operands of a binaryexpression node are the same.
+        // So, it is not easily possible to remove the typecasts that are there to make these conditions true.
+        // The only place for now where we can do this is for:
+        //    asmsub register pair parameter.
+
+        if(typecast.type in WordDatatypes) {
+            val fcall = typecast.parent as? IFunctionCall
+            if (fcall != null) {
+                val sub = fcall.target.targetStatement(program.namespace) as? Subroutine
+                if (sub != null && sub.isAsmSubroutine) {
+                    return listOf(IAstModification.ReplaceNode(typecast, typecast.expression, parent))
+                }
+            }
+        }
+
+        if(sourceDt in PassByReferenceDatatypes) {
             if(typecast.type==DataType.UWORD) {
                 return listOf(IAstModification.ReplaceNode(
                         typecast,

compiler/src/prog8/compiler/Compiler.kt

@@ -27,7 +27,8 @@ data class CompilationOptions(val output: OutputType,
                               val launcher: LauncherType,
                               val zeropage: ZeropageType,
                               val zpReserved: List<IntRange>,
-                              val floats: Boolean)
+                              val floats: Boolean,
+                              val compilationTarget: String?)
 
 
 class CompilerException(message: String?) : Exception(message)

compiler/src/prog8/compiler/Main.kt

@@ -4,7 +4,9 @@ import prog8.ast.AstToSourceCode
 import prog8.ast.Program
 import prog8.ast.base.*
 import prog8.ast.statements.Directive
+import prog8.compiler.target.C64Target
 import prog8.compiler.target.CompilationTarget
+import prog8.compiler.target.Cx16Target
 import prog8.optimizer.UnusedCodeRemover
 import prog8.optimizer.constantFold
 import prog8.optimizer.optimizeStatements
@@ -13,6 +15,7 @@ import prog8.parser.ModuleImporter
 import prog8.parser.ParsingFailedError
 import prog8.parser.moduleName
 import java.nio.file.Path
+import kotlin.system.exitProcess
 import kotlin.system.measureTimeMillis
 
 
@@ -25,12 +28,22 @@ class CompilationResult(val success: Boolean,
 fun compileProgram(filepath: Path,
                    optimize: Boolean,
                    writeAssembly: Boolean,
+                   compilationTarget: String,
                    outputDir: Path): CompilationResult {
     var programName = ""
     lateinit var programAst: Program
     lateinit var importedFiles: List<Path>
     val errors = ErrorReporter()
 
+    when(compilationTarget) {
+        C64Target.name -> CompilationTarget.instance = C64Target
+        Cx16Target.name -> CompilationTarget.instance = Cx16Target
+        else -> {
+            System.err.println("invalid compilation target")
+            exitProcess(1)
+        }
+    }
+
     try {
         val totalTime = measureTimeMillis {
             // import main module and everything it needs
@@ -79,7 +92,7 @@ fun compileProgram(filepath: Path,
 
 private fun parseImports(filepath: Path, errors: ErrorReporter): Triple<Program, CompilationOptions, List<Path>> {
     println("Parsing...")
-    val importer = ModuleImporter(errors)
+    val importer = ModuleImporter()
     val programAst = Program(moduleName(filepath.fileName), mutableListOf())
     importer.importModule(programAst, filepath)
     errors.handle()
@@ -90,11 +103,8 @@ private fun parseImports(filepath: Path, errors: ErrorReporter): Triple<Program,
     if (compilerOptions.launcher == LauncherType.BASIC && compilerOptions.output != OutputType.PRG)
         throw ParsingFailedError("${programAst.modules.first().position} BASIC launcher requires output type PRG.")
 
-    // if we're producing a PRG or BASIC program, include the c64utils and c64lib libraries
-    if (compilerOptions.launcher == LauncherType.BASIC || compilerOptions.output == OutputType.PRG) {
-        importer.importLibraryModule(programAst, "c64lib")
-        importer.importLibraryModule(programAst, "c64utils")
-    }
+    // depending on the machine and compiler options we may have to include some libraries
+    CompilationTarget.instance.machine.importLibs(compilerOptions, importer, programAst)
 
     // always import prog8lib and math
     importer.importLibraryModule(programAst, "math")
@@ -132,16 +142,26 @@ private fun determineCompilationOptions(program: Program): CompilationOptions {
             .map { it[0].int!!..it[1].int!! }
             .toList()
 
+    var target = (mainModule.statements.singleOrNull { it is Directive && it.directive == "%target" }
+            as? Directive)?.args?.single()?.name
+
+    when(target) {
+        C64Target.name -> CompilationTarget.instance = C64Target
+        Cx16Target.name -> CompilationTarget.instance = Cx16Target
+        null -> target = CompilationTarget.instance.name
+        else -> throw FatalAstException("invalid target")
+    }
+
     return CompilationOptions(
             if (outputType == null) OutputType.PRG else OutputType.valueOf(outputType),
             if (launcherType == null) LauncherType.BASIC else LauncherType.valueOf(launcherType),
-            zpType, zpReserved, floatsEnabled
+            zpType, zpReserved, floatsEnabled, target
     )
 }
 
 private fun processAst(programAst: Program, errors: ErrorReporter, compilerOptions: CompilationOptions) {
     // perform initial syntax checks and processings
-    println("Processing...")
+    println("Processing for target ${CompilationTarget.instance.name}...")
     programAst.checkIdentifiers(errors)
     errors.handle()
     programAst.constantFold(errors)
@@ -169,14 +189,13 @@ private fun optimizeAst(programAst: Program, errors: ErrorReporter) {
             break
     }
 
-    val remover = UnusedCodeRemover()
+    val remover = UnusedCodeRemover(errors)
     remover.visit(programAst)
     remover.applyModifications()
+    errors.handle()
 }
 
 private fun postprocessAst(programAst: Program, errors: ErrorReporter, compilerOptions: CompilationOptions) {
-    programAst.transformAssignments(errors)
-    errors.handle()
     programAst.addTypecasts(errors)
     errors.handle()
     programAst.variousCleanups()
@@ -190,16 +209,19 @@ private fun postprocessAst(programAst: Program, errors: ErrorReporter, compilerO
 private fun writeAssembly(programAst: Program, errors: ErrorReporter, outputDir: Path,
                           optimize: Boolean, compilerOptions: CompilationOptions): String {
     // asm generation directly from the Ast,
-    val zeropage = CompilationTarget.machine.getZeropage(compilerOptions)
     programAst.processAstBeforeAsmGeneration(errors)
     errors.handle()
 
     // printAst(programAst)
 
-    val assembly = CompilationTarget.asmGenerator(
+    if(compilerOptions.compilationTarget!=null && compilerOptions.compilationTarget != CompilationTarget.instance.name)
+        throw AssemblyError("program's compilation target differs from configured target")
+
+    CompilationTarget.instance.machine.initializeZeropage(compilerOptions)
+    val assembly = CompilationTarget.instance.asmGenerator(
             programAst,
             errors,
-            zeropage,
+            CompilationTarget.instance.machine.zeropage,
             compilerOptions,
             outputDir).compileToAssembly(optimize)
     assembly.assemble(compilerOptions)

compiler/src/prog8/compiler/Zeropage.kt

@@ -8,6 +8,12 @@ class ZeropageDepletedError(message: String) : Exception(message)
 
 abstract class Zeropage(protected val options: CompilationOptions) {
 
+    abstract val SCRATCH_B1 : Int      // temp storage for a single byte
+    abstract val SCRATCH_REG : Int     // temp storage for a register
+    abstract val SCRATCH_W1 : Int      // temp storage 1 for a word  $fb+$fc
+    abstract val SCRATCH_W2 : Int      // temp storage 2 for a word  $fb+$fc
+
+
     private val allocations = mutableMapOf<Int, Pair<String, DataType>>()
     val free = mutableListOf<Int>()     // subclasses must set this to the appropriate free locations.
 
@@ -16,7 +22,7 @@ abstract class Zeropage(protected val options: CompilationOptions) {
     fun available() = if(options.zeropage==ZeropageType.DONTUSE) 0 else free.size
 
     fun allocate(scopedname: String, datatype: DataType, position: Position?, errors: ErrorReporter): Int {
-        assert(scopedname.isEmpty() || !allocations.values.any { it.first==scopedname } ) {"isSameAs scopedname can't be allocated twice"}
+        assert(scopedname.isEmpty() || !allocations.values.any { it.first==scopedname } ) {"scopedname can't be allocated twice"}
 
         if(options.zeropage==ZeropageType.DONTUSE)
             throw CompilerException("zero page usage has been disabled")
@@ -39,13 +45,13 @@ abstract class Zeropage(protected val options: CompilationOptions) {
 
         if(free.size > 0) {
             if(size==1) {
-                for(candidate in free.min()!! .. free.max()!!+1) {
+                for(candidate in free.minOrNull()!! .. free.maxOrNull()!!+1) {
                     if(loneByte(candidate))
                         return makeAllocation(candidate, 1, datatype, scopedname)
                 }
                 return makeAllocation(free[0], 1, datatype, scopedname)
             }
-            for(candidate in free.min()!! .. free.max()!!+1) {
+            for(candidate in free.minOrNull()!! .. free.maxOrNull()!!+1) {
                 if (sequentialFree(candidate, size))
                     return makeAllocation(candidate, size, datatype, scopedname)
             }

compiler/src/prog8/compiler/target/CompilationTarget.kt

@@ -4,15 +4,50 @@ import prog8.ast.Program
 import prog8.ast.base.ErrorReporter
 import prog8.compiler.CompilationOptions
 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.cx16.CX16MachineDefinition
 import java.nio.file.Path
 
 
 internal interface CompilationTarget {
+    val name: String
+    val machine: IMachineDefinition
+    fun encodeString(str: String, altEncoding: Boolean): List<Short>
+    fun decodeString(bytes: List<Short>, altEncoding: Boolean): String
+    fun asmGenerator(program: Program, errors: ErrorReporter, zp: Zeropage, options: CompilationOptions, path: Path): IAssemblyGenerator
+    val asmForSystemReset: String
+    val initProcName: String?
+
     companion object {
-        lateinit var name: String
-        lateinit var machine: IMachineDefinition
-        lateinit var encodeString: (str: String, altEncoding: Boolean) -> List<Short>
-        lateinit var decodeString: (bytes: List<Short>, altEncoding: Boolean) -> String
-        lateinit var asmGenerator: (Program, ErrorReporter, Zeropage, CompilationOptions, Path) -> IAssemblyGenerator
+        lateinit var instance: CompilationTarget
     }
 }
+
+
+internal object C64Target: CompilationTarget {
+    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)
+    override fun decodeString(bytes: List<Short>, altEncoding: Boolean) =
+            if(altEncoding) Petscii.decodeScreencode(bytes, true) else Petscii.decodePetscii(bytes, true)
+    override fun asmGenerator(program: Program, errors: ErrorReporter, zp: Zeropage, options: CompilationOptions, path: Path) =
+            AsmGen(program, errors, zp, options, path)
+    override val asmForSystemReset = "  sei |  lda  #14 |  sta  $1 |  jmp  (c64.RESET_VEC)"
+    override val initProcName = "c64.init_system"
+}
+
+internal object Cx16Target: CompilationTarget {
+    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)
+    override fun decodeString(bytes: List<Short>, altEncoding: Boolean) =
+            if(altEncoding) Petscii.decodeScreencode(bytes, true) else Petscii.decodePetscii(bytes, true)
+    override fun asmGenerator(program: Program, errors: ErrorReporter, zp: Zeropage, options: CompilationOptions, path: Path) =
+            AsmGen(program, errors, zp, options, path)
+    override val asmForSystemReset = "  sei |  stz  cx16.d1prb |  jmp  (cx16.RESET_VEC)"
+    override val initProcName = "cx16.init_system"
+}

compiler/src/prog8/compiler/target/IMachineDefinition.kt

@@ -1,15 +1,38 @@
 package prog8.compiler.target
 
+import prog8.ast.Program
 import prog8.compiler.CompilationOptions
 import prog8.compiler.Zeropage
+import prog8.parser.ModuleImporter
 
 
-interface IMachineDefinition {
+internal interface IMachineFloat {
+    fun toDouble(): Double
+    fun makeFloatFillAsm(): String
+}
+
+internal enum class CpuType {
+    CPU6502,
+    CPU65c02
+}
+
+internal interface IMachineDefinition {
     val FLOAT_MAX_NEGATIVE: Double
     val FLOAT_MAX_POSITIVE: Double
     val FLOAT_MEM_SIZE: Int
+    val POINTER_MEM_SIZE: Int
+    val ESTACK_LO: Int
+    val ESTACK_HI: Int
+    val BASIC_LOAD_ADDRESS : Int
+    val RAW_LOAD_ADDRESS : Int
 
     val opcodeNames: Set<String>
+    var zeropage: Zeropage
+    val cpu: CpuType
 
-    fun getZeropage(compilerOptions: CompilationOptions): Zeropage
+    fun initializeZeropage(compilerOptions: CompilationOptions)
+    fun getFloat(num: Number): IMachineFloat
+    fun getFloatRomConst(number: Double): String?
+    fun importLibs(compilerOptions: CompilationOptions, importer: ModuleImporter, program: Program)
+    fun launchEmulator(programName: String)
 }

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

@@ -2,6 +2,7 @@ package prog8.compiler.target.c64
 
 import prog8.compiler.CompilationOptions
 import prog8.compiler.OutputType
+import prog8.compiler.target.CompilationTarget
 import prog8.compiler.target.IAssemblyProgram
 import prog8.compiler.target.generatedLabelPrefix
 import java.nio.file.Path
@@ -14,20 +15,20 @@ class AssemblyProgram(override val name: String, outputDir: Path) : IAssemblyPro
     private val viceMonListFile = outputDir.resolve("$name.vice-mon-list")
 
     override fun assemble(options: CompilationOptions) {
-        // add "-Wlong-branch"  to see warnings about conversion of branch instructions to jumps
+        // add "-Wlong-branch"  to see warnings about conversion of branch instructions to jumps (default = do this silently)
         val command = mutableListOf("64tass", "--ascii", "--case-sensitive", "--long-branch",
-                "-Wall", "-Wno-strict-bool", "-Wno-shadow", "-Werror", "-Wno-error=long-branch",
+                "-Wall", "-Wno-strict-bool", "-Wno-shadow", // "-Werror",
                 "--dump-labels", "--vice-labels", "-l", viceMonListFile.toString(), "--no-monitor")
 
         val outFile = when (options.output) {
             OutputType.PRG -> {
                 command.add("--cbm-prg")
-                println("\nCreating C-64 prg.")
+                println("\nCreating prg for target ${CompilationTarget.instance.name}.")
                 prgFile
             }
             OutputType.RAW -> {
                 command.add("--nostart")
-                println("\nCreating raw binary.")
+                println("\nCreating raw binary for target ${CompilationTarget.instance.name}.")
                 binFile
             }
         }

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

@@ -1,34 +1,96 @@
 package prog8.compiler.target.c64
 
-import prog8.compiler.CompilationOptions
-import prog8.compiler.CompilerException
-import prog8.compiler.Zeropage
-import prog8.compiler.ZeropageType
+import prog8.ast.Program
+import prog8.compiler.*
+import prog8.compiler.target.CpuType
 import prog8.compiler.target.IMachineDefinition
+import prog8.compiler.target.IMachineFloat
+import prog8.parser.ModuleImporter
+import java.io.IOException
+import java.math.RoundingMode
 import kotlin.math.absoluteValue
 import kotlin.math.pow
 
-object C64MachineDefinition: IMachineDefinition {
+internal object C64MachineDefinition: IMachineDefinition {
+
+    override val cpu = CpuType.CPU6502
 
     // 5-byte cbm MFLPT format limitations:
     override val FLOAT_MAX_POSITIVE = 1.7014118345e+38         // bytes: 255,127,255,255,255
     override val FLOAT_MAX_NEGATIVE = -1.7014118345e+38        // bytes: 255,255,255,255,255
     override val FLOAT_MEM_SIZE = 5
-    const val BASIC_LOAD_ADDRESS = 0x0801
-    const val RAW_LOAD_ADDRESS = 0xc000
+    override val POINTER_MEM_SIZE = 2
+    override val BASIC_LOAD_ADDRESS = 0x0801
+    override val RAW_LOAD_ADDRESS = 0xc000
 
     // the 2*256 byte evaluation stack (on which bytes, words, and even floats are stored during calculations)
     // and some heavily used string constants derived from the two values above
-    const val ESTACK_LO_VALUE       = 0xce00        //  $ce00-$ceff inclusive
-    const val ESTACK_HI_VALUE       = 0xcf00        //  $cf00-$cfff inclusive
-    const val ESTACK_LO_HEX         = "\$ce00"
-    const val ESTACK_LO_PLUS1_HEX   = "\$ce01"
-    const val ESTACK_LO_PLUS2_HEX   = "\$ce02"
-    const val ESTACK_HI_HEX         = "\$cf00"
-    const val ESTACK_HI_PLUS1_HEX   = "\$cf01"
-    const val ESTACK_HI_PLUS2_HEX   = "\$cf02"
+    override val ESTACK_LO = 0xce00        //  $ce00-$ceff inclusive
+    override val ESTACK_HI = 0xcf00        //  $ce00-$ceff inclusive
 
-    override fun getZeropage(compilerOptions: CompilationOptions) = C64Zeropage(compilerOptions)
+    override lateinit var zeropage: Zeropage
+
+    override fun getFloat(num: Number) = Mflpt5.fromNumber(num)
+
+    override fun getFloatRomConst(number: Double): String? {
+        // try to match the ROM float constants to save memory
+        val mflpt5 = Mflpt5.fromNumber(number)
+        val floatbytes = shortArrayOf(mflpt5.b0, mflpt5.b1, mflpt5.b2, mflpt5.b3, mflpt5.b4)
+        when {
+            floatbytes.contentEquals(shortArrayOf(0x00, 0x00, 0x00, 0x00, 0x00)) -> return "c64flt.ZERO"        // not a ROM const
+            floatbytes.contentEquals(shortArrayOf(0x82, 0x49, 0x0f, 0xda, 0xa1)) -> return "c64flt.FL_PIVAL"
+            floatbytes.contentEquals(shortArrayOf(0x90, 0x80, 0x00, 0x00, 0x00)) -> return "c64flt.FL_N32768"
+            floatbytes.contentEquals(shortArrayOf(0x81, 0x00, 0x00, 0x00, 0x00)) -> return "c64flt.FL_FONE"
+            floatbytes.contentEquals(shortArrayOf(0x80, 0x35, 0x04, 0xf3, 0x34)) -> return "c64flt.FL_SQRHLF"
+            floatbytes.contentEquals(shortArrayOf(0x81, 0x35, 0x04, 0xf3, 0x34)) -> return "c64flt.FL_SQRTWO"
+            floatbytes.contentEquals(shortArrayOf(0x80, 0x80, 0x00, 0x00, 0x00)) -> return "c64flt.FL_NEGHLF"
+            floatbytes.contentEquals(shortArrayOf(0x80, 0x31, 0x72, 0x17, 0xf8)) -> return "c64flt.FL_LOG2"
+            floatbytes.contentEquals(shortArrayOf(0x84, 0x20, 0x00, 0x00, 0x00)) -> return "c64flt.FL_TENC"
+            floatbytes.contentEquals(shortArrayOf(0x9e, 0x6e, 0x6b, 0x28, 0x00)) -> return "c64flt.FL_NZMIL"
+            floatbytes.contentEquals(shortArrayOf(0x80, 0x00, 0x00, 0x00, 0x00)) -> return "c64flt.FL_FHALF"
+            floatbytes.contentEquals(shortArrayOf(0x81, 0x38, 0xaa, 0x3b, 0x29)) -> return "c64flt.FL_LOGEB2"
+            floatbytes.contentEquals(shortArrayOf(0x81, 0x49, 0x0f, 0xda, 0xa2)) -> return "c64flt.FL_PIHALF"
+            floatbytes.contentEquals(shortArrayOf(0x83, 0x49, 0x0f, 0xda, 0xa2)) -> return "c64flt.FL_TWOPI"
+            floatbytes.contentEquals(shortArrayOf(0x7f, 0x00, 0x00, 0x00, 0x00)) -> return "c64flt.FL_FR4"
+            else -> {
+                // attempt to correct for a few rounding issues
+                when (number.toBigDecimal().setScale(10, RoundingMode.HALF_DOWN).toDouble()) {
+                    3.1415926536 -> return "c64flt.FL_PIVAL"
+                    1.4142135624 -> return "c64flt.FL_SQRTWO"
+                    0.7071067812 -> return "c64flt.FL_SQRHLF"
+                    0.6931471806 -> return "c64flt.FL_LOG2"
+                    else -> {}
+                }
+            }
+        }
+        return null
+    }
+
+    override fun importLibs(compilerOptions: CompilationOptions, importer: ModuleImporter, program: Program) {
+        if (compilerOptions.launcher == LauncherType.BASIC || compilerOptions.output == OutputType.PRG)
+            importer.importLibraryModule(program, "c64lib")
+    }
+
+    override fun launchEmulator(programName: String) {
+        for(emulator in listOf("x64sc", "x64")) {
+            println("\nStarting C-64 emulator $emulator...")
+            val cmdline = listOf(emulator, "-silent", "-moncommands", "$programName.vice-mon-list",
+                    "-autostartprgmode", "1", "-autostart-warp", "-autostart", programName + ".prg")
+            val processb = ProcessBuilder(cmdline).inheritIO()
+            val process: Process
+            try {
+                process=processb.start()
+            } catch(x: IOException) {
+                continue  // try the next emulator executable
+            }
+            process.waitFor()
+            break
+        }
+    }
+
+    override fun initializeZeropage(compilerOptions: CompilationOptions) {
+        zeropage = C64Zeropage(compilerOptions)
+    }
 
     // 6502 opcodes (including aliases and illegal opcodes), these cannot be used as variable or label names
     override val opcodeNames = setOf("adc", "ahx", "alr", "anc", "and", "ane", "arr", "asl", "asr", "axs", "bcc", "bcs",
@@ -42,15 +104,13 @@ object C64MachineDefinition: IMachineDefinition {
             "sta", "stx", "sty", "tas", "tax", "tay", "tsx", "txa", "txs", "tya", "xaa")
 
 
-    class C64Zeropage(options: CompilationOptions) : Zeropage(options) {
+    internal class C64Zeropage(options: CompilationOptions) : Zeropage(options) {
+
+        override val SCRATCH_B1 = 0x02      // temp storage for a single byte
+        override val SCRATCH_REG = 0x03     // temp storage for a register
+        override val SCRATCH_W1 = 0xfb      // temp storage 1 for a word  $fb+$fc
+        override val SCRATCH_W2 = 0xfd      // temp storage 2 for a word  $fb+$fc
 
-        companion object {
-            const val SCRATCH_B1 = 0x02
-            const val SCRATCH_REG = 0x03    // temp storage for a register
-            const val SCRATCH_REG_X = 0xfa    // temp storage for register X (the evaluation stack pointer)
-            const val SCRATCH_W1 = 0xfb     // $fb+$fc
-            const val SCRATCH_W2 = 0xfd     // $fd+$fe
-        }
 
         override val exitProgramStrategy: ExitProgramStrategy = when (options.zeropage) {
             ZeropageType.BASICSAFE, ZeropageType.DONTUSE -> ExitProgramStrategy.CLEAN_EXIT
@@ -65,7 +125,7 @@ object C64MachineDefinition: IMachineDefinition {
             if (options.zeropage == ZeropageType.FULL) {
                 free.addAll(0x04..0xf9)
                 free.add(0xff)
-                free.removeAll(listOf(SCRATCH_B1, SCRATCH_REG, SCRATCH_REG_X, SCRATCH_W1, SCRATCH_W1 + 1, SCRATCH_W2, SCRATCH_W2 + 1))
+                free.removeAll(listOf(SCRATCH_B1, SCRATCH_REG, SCRATCH_W1, SCRATCH_W1 + 1, SCRATCH_W2, SCRATCH_W2 + 1))
                 free.removeAll(listOf(0xa0, 0xa1, 0xa2, 0x91, 0xc0, 0xc5, 0xcb, 0xf5, 0xf6))        // these are updated by IRQ
             } else {
                 if (options.zeropage == ZeropageType.KERNALSAFE || options.zeropage == ZeropageType.FLOATSAFE) {
@@ -106,19 +166,17 @@ object C64MachineDefinition: IMachineDefinition {
                     free.clear()
                 }
             }
-            assert(SCRATCH_B1 !in free)
-            assert(SCRATCH_REG !in free)
-            assert(SCRATCH_REG_X !in free)
-            assert(SCRATCH_W1 !in free)
-            assert(SCRATCH_W2 !in free)
+            require(SCRATCH_B1 !in free)
+            require(SCRATCH_REG !in free)
+            require(SCRATCH_W1 !in free)
+            require(SCRATCH_W2 !in free)
 
             for (reserved in options.zpReserved)
                 reserve(reserved)
         }
     }
 
-
-    data class Mflpt5(val b0: Short, val b1: Short, val b2: Short, val b3: Short, val b4: Short) {
+    internal data class Mflpt5(val b0: Short, val b1: Short, val b2: Short, val b3: Short, val b4: Short): IMachineFloat {
 
         companion object {
             val zero = Mflpt5(0, 0, 0, 0, 0)
@@ -165,7 +223,7 @@ object C64MachineDefinition: IMachineDefinition {
             }
         }
 
-        fun toDouble(): Double {
+        override fun toDouble(): Double {
             if (this == zero) return 0.0
             val exp = b0 - 128
             val sign = (b1.toInt() and 0x80) > 0
@@ -173,5 +231,14 @@ object C64MachineDefinition: IMachineDefinition {
             val result = number.toDouble() * (2.0).pow(exp) / 0x100000000
             return if (sign) -result else result
         }
+
+        override fun makeFloatFillAsm(): String {
+            val b0 = "$" + b0.toString(16).padStart(2, '0')
+            val b1 = "$" + b1.toString(16).padStart(2, '0')
+            val b2 = "$" + b2.toString(16).padStart(2, '0')
+            val b3 = "$" + b3.toString(16).padStart(2, '0')
+            val b4 = "$" + b4.toString(16).padStart(2, '0')
+            return "$b0, $b1, $b2, $b3, $b4"
+        }
     }
 }

compiler/src/prog8/compiler/target/c64/codegen/AsmOptimizer.kt

@@ -1,8 +1,5 @@
 package prog8.compiler.target.c64.codegen
 
-import prog8.compiler.target.c64.C64MachineDefinition.ESTACK_LO_HEX
-import prog8.compiler.target.c64.C64MachineDefinition.ESTACK_LO_PLUS1_HEX
-
 
 // note: see https://wiki.nesdev.com/w/index.php/6502_assembly_optimisations
 
@@ -87,10 +84,10 @@ private fun optimizeCmpSequence(linesByFour: List<List<IndexedValue<String>>>):
     // the repeated lda can be removed
     val mods = mutableListOf<Modification>()
     for(lines in linesByFour) {
-        if(lines[0].value.trim()=="lda  $ESTACK_LO_PLUS1_HEX,x" &&
+        if(lines[0].value.trim()=="lda  P8ESTACK_LO+1,x" &&
                 lines[1].value.trim().startsWith("cmp ") &&
                 lines[2].value.trim().startsWith("beq ") &&
-                lines[3].value.trim()=="lda  $ESTACK_LO_PLUS1_HEX,x") {
+                lines[3].value.trim()=="lda  P8ESTACK_LO+1,x") {
             mods.add(Modification(lines[3].index, true, null)) // remove the second lda
         }
     }
@@ -102,10 +99,10 @@ private fun optimizeUselessStackByteWrites(linesByFour: List<List<IndexedValue<S
     // this is a lot harder for word values because the instruction sequence varies.
     val mods = mutableListOf<Modification>()
     for(lines in linesByFour) {
-        if(lines[0].value.trim()=="sta  $ESTACK_LO_HEX,x" &&
+        if(lines[0].value.trim()=="sta  P8ESTACK_LO,x" &&
                 lines[1].value.trim()=="dex" &&
                 lines[2].value.trim()=="inx" &&
-                lines[3].value.trim()=="lda  $ESTACK_LO_HEX,x") {
+                lines[3].value.trim()=="lda  P8ESTACK_LO,x") {
             mods.add(Modification(lines[1].index, true, null))
             mods.add(Modification(lines[2].index, true, null))
             mods.add(Modification(lines[3].index, true, null))
@@ -154,7 +151,8 @@ private fun optimizeSameAssignments(linesByFourteen: List<List<IndexedValue<Stri
         }
 
         if(first.startsWith("lda") && second.startsWith("ldy") && third.startsWith("sta") && fourth.startsWith("sty") &&
-                fifth.startsWith("lda") && sixth.startsWith("ldy") && seventh.startsWith("jsr  c64flt.copy_float")) {
+                fifth.startsWith("lda") && sixth.startsWith("ldy") &&
+                (seventh.startsWith("jsr  c64flt.copy_float") || seventh.startsWith("jsr  cx16flt.copy_float"))) {
 
             val nineth = pair[8].value.trimStart()
             val tenth = pair[9].value.trimStart()
@@ -164,7 +162,8 @@ private fun optimizeSameAssignments(linesByFourteen: List<List<IndexedValue<Stri
             val fourteenth = pair[13].value.trimStart()
 
             if(eighth.startsWith("lda") && nineth.startsWith("ldy") && tenth.startsWith("sta") && eleventh.startsWith("sty") &&
-                    twelveth.startsWith("lda") && thirteenth.startsWith("ldy") && fourteenth.startsWith("jsr  c64flt.copy_float")) {
+                    twelveth.startsWith("lda") && thirteenth.startsWith("ldy") &&
+                    (fourteenth.startsWith("jsr  c64flt.copy_float") || fourteenth.startsWith("jsr  cx16flt.copy_float"))) {
 
                 if(first.substring(4) == eighth.substring(4) && second.substring(4)==nineth.substring(4)) {
                     // identical float init

compiler/src/prog8/compiler/target/c64/codegen/BuiltinFunctionsAsmGen.kt

@@ -6,11 +6,6 @@ import prog8.ast.base.*
 import prog8.ast.expressions.*
 import prog8.ast.statements.FunctionCallStatement
 import prog8.compiler.AssemblyError
-import prog8.compiler.target.c64.C64MachineDefinition.C64Zeropage
-import prog8.compiler.target.c64.C64MachineDefinition.ESTACK_HI_HEX
-import prog8.compiler.target.c64.C64MachineDefinition.ESTACK_HI_PLUS1_HEX
-import prog8.compiler.target.c64.C64MachineDefinition.ESTACK_LO_HEX
-import prog8.compiler.target.c64.C64MachineDefinition.ESTACK_LO_PLUS1_HEX
 import prog8.compiler.toHex
 import prog8.functions.FSignature
 
@@ -35,6 +30,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
 
         when (functionName) {
             "msb" -> funcMsb(fcall)
+            "lsb" -> funcLsb(fcall)
             "mkword" -> funcMkword(fcall, func)
             "abs" -> funcAbs(fcall, func)
             "swap" -> funcSwap(fcall)
@@ -46,8 +42,6 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
             "ln", "log2", "sqrt", "rad",
             "deg", "round", "floor", "ceil",
             "rdnf" -> funcVariousFloatFuncs(fcall, func, functionName)
-            "lsl" -> funcLsl(fcall)
-            "lsr" -> funcLsr(fcall)
             "rol" -> funcRol(fcall)
             "rol2" -> funcRol2(fcall)
             "ror" -> funcRor(fcall)
@@ -57,7 +51,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
             "rsave" -> {
                 // save cpu status flag and all registers A, X, Y.
                 // see http://6502.org/tutorials/register_preservation.html
-                asmgen.out(" php |  sta  ${C64Zeropage.SCRATCH_REG} | pha  | txa  | pha  | tya  | pha  | lda  ${C64Zeropage.SCRATCH_REG}")
+                asmgen.out(" php |  sta  P8ZP_SCRATCH_REG | pha  | txa  | pha  | tya  | pha  | lda  P8ZP_SCRATCH_REG")
             }
             "rrestore" -> {
                 // restore all registers and cpu status flag
@@ -78,15 +72,15 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
         val variable = fcall.args.single()
         if (variable is IdentifierReference) {
             val decl = variable.targetVarDecl(program.namespace)!!
-            val varName = asmgen.asmIdentifierName(variable)
-            val numElements = decl.arraysize!!.size()
+            val varName = asmgen.asmVariableName(variable)
+            val numElements = decl.arraysize!!.constIndex()
             when (decl.datatype) {
                 DataType.ARRAY_UB, DataType.ARRAY_B -> {
                     asmgen.out("""
                                     lda  #<$varName
                                     ldy  #>$varName
-                                    sta  ${C64Zeropage.SCRATCH_W1}
-                                    sty  ${C64Zeropage.SCRATCH_W1 + 1}
+                                    sta  P8ZP_SCRATCH_W1
+                                    sty  P8ZP_SCRATCH_W1+1
                                     lda  #$numElements
                                     jsr  prog8_lib.reverse_b
                                 """)
@@ -95,8 +89,8 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                     asmgen.out("""
                                     lda  #<$varName
                                     ldy  #>$varName
-                                    sta  ${C64Zeropage.SCRATCH_W1}
-                                    sty  ${C64Zeropage.SCRATCH_W1 + 1}
+                                    sta  P8ZP_SCRATCH_W1
+                                    sty  P8ZP_SCRATCH_W1+1
                                     lda  #$numElements
                                     jsr  prog8_lib.reverse_w
                                 """)
@@ -105,8 +99,8 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                     asmgen.out("""
                                     lda  #<$varName
                                     ldy  #>$varName
-                                    sta  ${C64Zeropage.SCRATCH_W1}
-                                    sty  ${C64Zeropage.SCRATCH_W1 + 1}
+                                    sta  P8ZP_SCRATCH_W1
+                                    sty  P8ZP_SCRATCH_W1+1
                                     lda  #$numElements
                                     jsr  prog8_lib.reverse_f
                                 """)
@@ -120,17 +114,17 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
         val variable = fcall.args.single()
         if (variable is IdentifierReference) {
             val decl = variable.targetVarDecl(program.namespace)!!
-            val varName = asmgen.asmIdentifierName(variable)
-            val numElements = decl.arraysize!!.size()
+            val varName = asmgen.asmVariableName(variable)
+            val numElements = decl.arraysize!!.constIndex()
             when (decl.datatype) {
                 DataType.ARRAY_UB, DataType.ARRAY_B -> {
                     asmgen.out("""
                                     lda  #<$varName
                                     ldy  #>$varName
-                                    sta  ${C64Zeropage.SCRATCH_W1}
-                                    sty  ${C64Zeropage.SCRATCH_W1 + 1}
+                                    sta  P8ZP_SCRATCH_W1
+                                    sty  P8ZP_SCRATCH_W1+1
                                     lda  #$numElements
-                                    sta  ${C64Zeropage.SCRATCH_B1}
+                                    sta  P8ZP_SCRATCH_B1
                                 """)
                     asmgen.out(if (decl.datatype == DataType.ARRAY_UB) "  jsr  prog8_lib.sort_ub" else "  jsr  prog8_lib.sort_b")
                 }
@@ -138,10 +132,10 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                     asmgen.out("""
                                     lda  #<$varName
                                     ldy  #>$varName
-                                    sta  ${C64Zeropage.SCRATCH_W1}
-                                    sty  ${C64Zeropage.SCRATCH_W1 + 1}
+                                    sta  P8ZP_SCRATCH_W1
+                                    sty  P8ZP_SCRATCH_W1+1
                                     lda  #$numElements
-                                    sta  ${C64Zeropage.SCRATCH_B1}
+                                    sta  P8ZP_SCRATCH_B1
                                 """)
                     asmgen.out(if (decl.datatype == DataType.ARRAY_UW) "  jsr  prog8_lib.sort_uw" else "  jsr  prog8_lib.sort_w")
                 }
@@ -173,7 +167,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                         }
                     }
                     is IdentifierReference -> {
-                        val variable = asmgen.asmIdentifierName(what)
+                        val variable = asmgen.asmVariableName(what)
                         asmgen.out("  lda  $variable |  lsr  a |  bcc  + |  ora  #\$80 |+  |  sta  $variable")
                     }
                     else -> throw AssemblyError("weird type")
@@ -187,7 +181,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                         asmgen.out("  jsr  prog8_lib.ror2_array_uw")
                     }
                     is IdentifierReference -> {
-                        val variable = asmgen.asmIdentifierName(what)
+                        val variable = asmgen.asmVariableName(what)
                         asmgen.out("  lsr  $variable+1 |  ror  $variable |  bcc  + |  lda  $variable+1 |  ora  #\$80 |  sta  $variable+1 |+  ")
                     }
                     else -> throw AssemblyError("weird type")
@@ -216,16 +210,16 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                             asmgen.translateExpression(what.addressExpression)
                             asmgen.out("""
                         inx
-                        lda  $ESTACK_LO_HEX,x
+                        lda  P8ESTACK_LO,x
                         sta  (+) + 1
-                        lda  $ESTACK_HI_HEX,x
+                        lda  P8ESTACK_HI,x
                         sta  (+) + 2
     +                   ror  ${'$'}ffff            ; modified                    
                                         """)
                         }
                     }
                     is IdentifierReference -> {
-                        val variable = asmgen.asmIdentifierName(what)
+                        val variable = asmgen.asmVariableName(what)
                         asmgen.out("  ror  $variable")
                     }
                     else -> throw AssemblyError("weird type")
@@ -239,7 +233,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                         asmgen.out("  jsr  prog8_lib.ror_array_uw")
                     }
                     is IdentifierReference -> {
-                        val variable = asmgen.asmIdentifierName(what)
+                        val variable = asmgen.asmVariableName(what)
                         asmgen.out("  ror  $variable+1 |  ror  $variable")
                     }
                     else -> throw AssemblyError("weird type")
@@ -270,7 +264,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                         }
                     }
                     is IdentifierReference -> {
-                        val variable = asmgen.asmIdentifierName(what)
+                        val variable = asmgen.asmVariableName(what)
                         asmgen.out("  lda  $variable |  cmp  #\$80 |  rol  a |  sta  $variable")
                     }
                     else -> throw AssemblyError("weird type")
@@ -284,7 +278,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                         asmgen.out("  jsr  prog8_lib.rol2_array_uw")
                     }
                     is IdentifierReference -> {
-                        val variable = asmgen.asmIdentifierName(what)
+                        val variable = asmgen.asmVariableName(what)
                         asmgen.out("  asl  $variable |  rol  $variable+1 |  bcc  + |  inc  $variable |+  ")
                     }
                     else -> throw AssemblyError("weird type")
@@ -313,16 +307,16 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                             asmgen.translateExpression(what.addressExpression)
                             asmgen.out("""
                         inx
-                        lda  $ESTACK_LO_HEX,x
+                        lda  P8ESTACK_LO,x
                         sta  (+) + 1
-                        lda  $ESTACK_HI_HEX,x
+                        lda  P8ESTACK_HI,x
                         sta  (+) + 2
     +                   rol  ${'$'}ffff            ; modified                    
                                         """)
                         }
                     }
                     is IdentifierReference -> {
-                        val variable = asmgen.asmIdentifierName(what)
+                        val variable = asmgen.asmVariableName(what)
                         asmgen.out("  rol  $variable")
                     }
                     else -> throw AssemblyError("weird type")
@@ -336,7 +330,7 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
                         asmgen.out("  jsr  prog8_lib.rol_array_uw")
                     }
                     is IdentifierReference -> {
-                        val variable = asmgen.asmIdentifierName(what)
+                        val variable = asmgen.asmVariableName(what)
                         asmgen.out("  rol  $variable |  rol  $variable+1")
                     }
                     else -> throw AssemblyError("weird type")
@@ -346,132 +340,6 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
         }
     }
 
-    private fun funcLsr(fcall: IFunctionCall) {
-        val what = fcall.args.single()
-        val dt = what.inferType(program)
-        when (dt.typeOrElse(DataType.STRUCT)) {
-            DataType.UBYTE -> {
-                when (what) {
-                    is IdentifierReference -> asmgen.out("  lsr  ${asmgen.asmIdentifierName(what)}")
-                    is DirectMemoryRead -> {
-                        if (what.addressExpression is NumericLiteralValue) {
-                            val number = (what.addressExpression as NumericLiteralValue).number
-                            asmgen.out("  lsr  ${number.toHex()}")
-                        } else {
-                            asmgen.translateExpression(what.addressExpression)
-                            asmgen.out("""
-                        inx
-                        lda  $ESTACK_LO_HEX,x
-                        sta  (+) + 1
-                        lda  $ESTACK_HI_HEX,x
-                        sta  (+) + 2
-    +                   lsr  ${'$'}ffff            ; modified                    
-                                        """)
-                        }
-                    }
-                    is ArrayIndexedExpression -> {
-                        asmgen.translateExpression(what.identifier)
-                        asmgen.translateExpression(what.arrayspec.index)
-                        asmgen.out("  jsr  prog8_lib.lsr_array_ub")
-                    }
-                    else -> throw AssemblyError("weird type")
-                }
-            }
-            DataType.BYTE -> {
-                when (what) {
-                    is ArrayIndexedExpression -> {
-                        asmgen.translateExpression(what.identifier)
-                        asmgen.translateExpression(what.arrayspec.index)
-                        asmgen.out("  jsr  prog8_lib.lsr_array_b")
-                    }
-                    is IdentifierReference -> {
-                        val variable = asmgen.asmIdentifierName(what)
-                        asmgen.out("  lda  $variable |  asl  a |  ror  $variable")
-                    }
-                    else -> throw AssemblyError("weird type")
-                }
-            }
-            DataType.UWORD -> {
-                when (what) {
-                    is ArrayIndexedExpression -> {
-                        asmgen.translateExpression(what.identifier)
-                        asmgen.translateExpression(what.arrayspec.index)
-                        asmgen.out("  jsr  prog8_lib.lsr_array_uw")
-                    }
-                    is IdentifierReference -> {
-                        val variable = asmgen.asmIdentifierName(what)
-                        asmgen.out(" lsr  $variable+1 |  ror  $variable")
-                    }
-                    else -> throw AssemblyError("weird type")
-                }
-            }
-            DataType.WORD -> {
-                when (what) {
-                    is ArrayIndexedExpression -> {
-                        asmgen.translateExpression(what.identifier)
-                        asmgen.translateExpression(what.arrayspec.index)
-                        asmgen.out("  jsr  prog8_lib.lsr_array_w")
-                    }
-                    is IdentifierReference -> {
-                        val variable = asmgen.asmIdentifierName(what)
-                        asmgen.out("  lda  $variable+1 |  asl a  |  ror  $variable+1 |  ror  $variable")
-                    }
-                    else -> throw AssemblyError("weird type")
-                }
-            }
-            else -> throw AssemblyError("weird type")
-        }
-    }
-
-    private fun funcLsl(fcall: IFunctionCall) {
-        val what = fcall.args.single()
-        val dt = what.inferType(program)
-        when (dt.typeOrElse(DataType.STRUCT)) {
-            in ByteDatatypes -> {
-                when (what) {
-                    is IdentifierReference -> asmgen.out("  asl  ${asmgen.asmIdentifierName(what)}")
-                    is DirectMemoryRead -> {
-                        if (what.addressExpression is NumericLiteralValue) {
-                            val number = (what.addressExpression as NumericLiteralValue).number
-                            asmgen.out("  asl  ${number.toHex()}")
-                        } else {
-                            asmgen.translateExpression(what.addressExpression)
-                            asmgen.out("""
-                        inx
-                        lda  $ESTACK_LO_HEX,x
-                        sta  (+) + 1
-                        lda  $ESTACK_HI_HEX,x
-                        sta  (+) + 2
-    +                   asl  ${'$'}ffff            ; modified                    
-                                        """)
-                        }
-                    }
-                    is ArrayIndexedExpression -> {
-                        asmgen.translateExpression(what.identifier)
-                        asmgen.translateExpression(what.arrayspec.index)
-                        asmgen.out("  jsr  prog8_lib.lsl_array_b")
-                    }
-                    else -> throw AssemblyError("weird type")
-                }
-            }
-            in WordDatatypes -> {
-                when (what) {
-                    is ArrayIndexedExpression -> {
-                        asmgen.translateExpression(what.identifier)
-                        asmgen.translateExpression(what.arrayspec.index)
-                        asmgen.out("  jsr  prog8_lib.lsl_array_w")
-                    }
-                    is IdentifierReference -> {
-                        val variable = asmgen.asmIdentifierName(what)
-                        asmgen.out(" asl  $variable |  rol  $variable+1")
-                    }
-                    else -> throw AssemblyError("weird type")
-                }
-            }
-            else -> throw AssemblyError("weird type")
-        }
-    }
-
     private fun funcVariousFloatFuncs(fcall: IFunctionCall, func: FSignature, functionName: String) {
         translateFunctionArguments(fcall.args, func)
         asmgen.out("  jsr  c64flt.func_$functionName")
@@ -515,16 +383,21 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
     }
 
     private fun funcStrlen(fcall: IFunctionCall) {
-        outputPushAddressOfIdentifier(fcall.args[0])
-        asmgen.out("  jsr  prog8_lib.func_strlen")
+        val name = asmgen.asmVariableName(fcall.args[0] as IdentifierReference)
+        asmgen.out("""
+            lda  #<$name
+            ldy  #>$name
+            jsr  prog8_lib.strlen
+            sta  P8ESTACK_LO,x
+            dex""")
     }
 
     private fun funcSwap(fcall: IFunctionCall) {
         val first = fcall.args[0]
         val second = fcall.args[1]
         if(first is IdentifierReference && second is IdentifierReference) {
-            val firstName = asmgen.asmIdentifierName(first)
-            val secondName = asmgen.asmIdentifierName(second)
+            val firstName = asmgen.asmVariableName(first)
+            val secondName = asmgen.asmVariableName(second)
             val dt = first.inferType(program)
             if(dt.istype(DataType.BYTE) || dt.istype(DataType.UBYTE)) {
                 asmgen.out(" ldy  $firstName |  lda  $secondName |  sta  $firstName |  tya |  sta  $secondName")
@@ -546,13 +419,13 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
             if(dt.istype(DataType.FLOAT)) {
                 asmgen.out("""
                     lda  #<$firstName
-                    sta  ${C64Zeropage.SCRATCH_W1}
+                    sta  P8ZP_SCRATCH_W1
                     lda  #>$firstName
-                    sta  ${C64Zeropage.SCRATCH_W1+1}
+                    sta  P8ZP_SCRATCH_W1+1
                     lda  #<$secondName
-                    sta  ${C64Zeropage.SCRATCH_W2}
+                    sta  P8ZP_SCRATCH_W2
                     lda  #>$secondName
-                    sta  ${C64Zeropage.SCRATCH_W2+1}
+                    sta  P8ZP_SCRATCH_W2+1
                     jsr  c64flt.swap_floats
                 """)
                 return
@@ -575,8 +448,10 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
     }
 
     private fun funcMkword(fcall: IFunctionCall, func: FSignature) {
-        translateFunctionArguments(fcall.args, func)
-        asmgen.out("  inx | lda  $ESTACK_LO_HEX,x  | sta  $ESTACK_HI_PLUS1_HEX,x")
+        // trick: push the args in reverse order (msb first, lsb second) this saves some instructions
+        asmgen.translateExpression(fcall.args[1])
+        asmgen.translateExpression(fcall.args[0])
+        asmgen.out("  inx | lda  P8ESTACK_LO,x  | sta  P8ESTACK_HI+1,x")
     }
 
     private fun funcMsb(fcall: IFunctionCall) {
@@ -584,39 +459,43 @@ internal class BuiltinFunctionsAsmGen(private val program: Program, private val
         if (arg.inferType(program).typeOrElse(DataType.STRUCT) !in WordDatatypes)
             throw AssemblyError("msb required word argument")
         if (arg is NumericLiteralValue)
-            throw AssemblyError("should have been const-folded")
+            throw AssemblyError("msb(const) should have been const-folded away")
         if (arg is IdentifierReference) {
-            val sourceName = asmgen.asmIdentifierName(arg)
-            asmgen.out("  lda  $sourceName+1 |  sta  $ESTACK_LO_HEX,x |  dex")
+            val sourceName = asmgen.asmVariableName(arg)
+            asmgen.out("  lda  $sourceName+1 |  sta  P8ESTACK_LO,x |  dex")
         } else {
             asmgen.translateExpression(arg)
-            asmgen.out("  lda  $ESTACK_HI_PLUS1_HEX,x |  sta  $ESTACK_LO_PLUS1_HEX,x")
+            asmgen.out("  lda  P8ESTACK_HI+1,x |  sta  P8ESTACK_LO+1,x")
+        }
+    }
+
+    private fun funcLsb(fcall: IFunctionCall) {
+        val arg = fcall.args.single()
+        if (arg.inferType(program).typeOrElse(DataType.STRUCT) !in WordDatatypes)
+            throw AssemblyError("lsb required word argument")
+        if (arg is NumericLiteralValue)
+            throw AssemblyError("lsb(const) should have been const-folded away")
+        if (arg is IdentifierReference) {
+            val sourceName = asmgen.asmVariableName(arg)
+            asmgen.out("  lda  $sourceName |  sta  P8ESTACK_LO,x |  dex")
+        } else {
+            asmgen.translateExpression(arg)
+            // just ignore any high-byte
         }
     }
 
     private fun outputPushAddressAndLenghtOfArray(arg: Expression) {
         arg as IdentifierReference
-        val identifierName = asmgen.asmIdentifierName(arg)
-        val size = arg.targetVarDecl(program.namespace)!!.arraysize!!.size()!!
+        val identifierName = asmgen.asmVariableName(arg)
+        val size = arg.targetVarDecl(program.namespace)!!.arraysize!!.constIndex()!!
         asmgen.out("""
                     lda  #<$identifierName
-                    sta  $ESTACK_LO_HEX,x
+                    sta  P8ESTACK_LO,x
                     lda  #>$identifierName
-                    sta  $ESTACK_HI_HEX,x
+                    sta  P8ESTACK_HI,x
                     dex
                     lda  #$size
-                    sta  $ESTACK_LO_HEX,x
-                    dex
-                    """)
-    }
-
-    private fun outputPushAddressOfIdentifier(arg: Expression) {
-        val identifierName = asmgen.asmIdentifierName(arg as IdentifierReference)
-        asmgen.out("""
-                    lda  #<$identifierName
-                    sta  $ESTACK_LO_HEX,x
-                    lda  #>$identifierName
-                    sta  $ESTACK_HI_HEX,x
+                    sta  P8ESTACK_LO,x
                     dex
                     """)
     }

compiler/src/prog8/compiler/target/c64/codegen/ExpressionsAsmGen.kt

@@ -4,12 +4,8 @@ import prog8.ast.Program
 import prog8.ast.base.*
 import prog8.ast.expressions.*
 import prog8.compiler.AssemblyError
-import prog8.compiler.target.c64.C64MachineDefinition
-import prog8.compiler.target.c64.C64MachineDefinition.ESTACK_HI_HEX
-import prog8.compiler.target.c64.C64MachineDefinition.ESTACK_HI_PLUS1_HEX
-import prog8.compiler.target.c64.C64MachineDefinition.ESTACK_LO_HEX
-import prog8.compiler.target.c64.C64MachineDefinition.ESTACK_LO_PLUS1_HEX
-import prog8.compiler.target.c64.C64MachineDefinition.ESTACK_LO_PLUS2_HEX
+import prog8.compiler.target.CompilationTarget
+import prog8.compiler.target.CpuType
 import prog8.compiler.toHex
 import prog8.functions.BuiltinFunctions
 import kotlin.math.absoluteValue
@@ -20,7 +16,7 @@ internal class ExpressionsAsmGen(private val program: Program, private val asmge
         when(expression) {
             is PrefixExpression -> translateExpression(expression)
             is BinaryExpression -> translateExpression(expression)
-            is ArrayIndexedExpression -> translatePushFromArray(expression)
+            is ArrayIndexedExpression -> translateExpression(expression)
             is TypecastExpression -> translateExpression(expression)
             is AddressOf -> translateExpression(expression)
             is DirectMemoryRead -> translateExpression(expression)
@@ -46,20 +42,33 @@ internal class ExpressionsAsmGen(private val program: Program, private val asmge
                     // result value in cpu or status registers, put it on the stack
                     if (reg.registerOrPair != null) {
                         when (reg.registerOrPair) {
-                            RegisterOrPair.A -> asmgen.out("  sta  $ESTACK_LO_HEX,x |  dex")
-                            RegisterOrPair.Y -> asmgen.out("  tya |  sta  $ESTACK_LO_HEX,x |  dex")
-                            RegisterOrPair.AY -> asmgen.out("  sta  $ESTACK_LO_HEX,x |  tya |  sta  $ESTACK_HI_HEX,x |  dex")
+                            RegisterOrPair.A -> asmgen.out("  sta  P8ESTACK_LO,x |  dex")
+                            RegisterOrPair.Y -> asmgen.out("  tya |  sta  P8ESTACK_LO,x |  dex")
+                            RegisterOrPair.AY -> asmgen.out("  sta  P8ESTACK_LO,x |  tya |  sta  P8ESTACK_HI,x |  dex")
                             RegisterOrPair.X -> {
                                 // return value in X register has been discarded, just push a zero
-                                asmgen.out("  lda  #0 |  sta  $ESTACK_LO_HEX,x |  dex")
+                                if(CompilationTarget.instance.machine.cpu==CpuType.CPU65c02)
+                                    asmgen.out("  stz  P8ESTACK_LO,x")
+                                else
+                                    asmgen.out("  lda  #0 |  sta  P8ESTACK_LO,x")
+                                asmgen.out("  dex")
                             }
                             RegisterOrPair.AX -> {
                                 // return value in X register has been discarded, just push a zero in this place
-                                asmgen.out("  sta  $ESTACK_LO_HEX,x |  lda  #0 |  sta  $ESTACK_HI_HEX,x |  dex")
+                                asmgen.out("  sta  P8ESTACK_LO,x")
+                                if(CompilationTarget.instance.machine.cpu==CpuType.CPU65c02)
+                                    asmgen.out("  stz  P8ESTACK_HI,x")
+                                else
+                                    asmgen.out("  lda  #0 |  sta  P8ESTACK_HI,x")
+                                asmgen.out("  dex")
                             }
                             RegisterOrPair.XY -> {
                                 // return value in X register has been discarded, just push a zero in this place
-                                asmgen.out("  lda  #0 |  sta  $ESTACK_LO_HEX,x |  tya |  sta  $ESTACK_HI_HEX,x |  dex")
+                                if(CompilationTarget.instance.machine.cpu==CpuType.CPU65c02)
+                                    asmgen.out("  stz  P8ESTACK_LO,x")
+                                else
+                                    asmgen.out("  lda  #0 |  sta  P8ESTACK_LO,x")
+                                asmgen.out("  tya |  sta  P8ESTACK_HI,x |  dex")
                             }
                         }
                     }
@@ -75,7 +84,12 @@ internal class ExpressionsAsmGen(private val program: Program, private val asmge
             DataType.UBYTE -> {
                 when(expr.type) {
                     DataType.UBYTE, DataType.BYTE -> {}
-                    DataType.UWORD, DataType.WORD -> asmgen.out("  lda  #0  |  sta  $ESTACK_HI_PLUS1_HEX,x")
+                    DataType.UWORD, DataType.WORD -> {
+                        if(CompilationTarget.instance.machine.cpu==CpuType.CPU65c02)
+                            asmgen.out("  stz  P8ESTACK_HI+1,x")
+                        else
+                            asmgen.out("  lda  #0  |  sta  P8ESTACK_HI+1,x")
+                    }
                     DataType.FLOAT -> asmgen.out(" jsr  c64flt.stack_ub2float")
                     in PassByReferenceDatatypes -> throw AssemblyError("cannot cast to a pass-by-reference datatype")
                     else -> throw AssemblyError("weird type")
@@ -84,7 +98,15 @@ internal class ExpressionsAsmGen(private val program: Program, private val asmge
             DataType.BYTE -> {
                 when(expr.type) {
                     DataType.UBYTE, DataType.BYTE -> {}
-                    DataType.UWORD, DataType.WORD -> asmgen.out("  lda  $ESTACK_LO_PLUS1_HEX,x  |  ${asmgen.signExtendAtoMsb("$ESTACK_HI_PLUS1_HEX,x")}")
+                    DataType.UWORD, DataType.WORD -> {
+                        // sign extend
+                        asmgen.out(""" 
+                            lda  P8ESTACK_LO+1,x
+                            ora  #$7f
+                            bmi  +
+                            lda  #0
++                           sta  P8ESTACK_HI+1,x""")
+                    }
                     DataType.FLOAT -> asmgen.out(" jsr  c64flt.stack_b2float")
                     in PassByReferenceDatatypes -> throw AssemblyError("cannot cast to a pass-by-reference datatype")
                     else -> throw AssemblyError("weird type")
@@ -125,48 +147,41 @@ internal class ExpressionsAsmGen(private val program: Program, private val asmge
     }
 
     private fun translateExpression(expr: AddressOf) {
-        val name = asmgen.asmIdentifierName(expr.identifier)
-        asmgen.out("  lda  #<$name |  sta  $ESTACK_LO_HEX,x |  lda  #>$name  |  sta  $ESTACK_HI_HEX,x  | dex")
+        val name = asmgen.asmVariableName(expr.identifier)
+        asmgen.out("  lda  #<$name |  sta  P8ESTACK_LO,x |  lda  #>$name  |  sta  P8ESTACK_HI,x  | dex")
     }
 
     private fun translateExpression(expr: DirectMemoryRead) {
         when(expr.addressExpression) {
             is NumericLiteralValue -> {
                 val address = (expr.addressExpression as NumericLiteralValue).number.toInt()
-                asmgen.out("  lda  ${address.toHex()} |  sta  $ESTACK_LO_HEX,x |  dex")
+                asmgen.out("  lda  ${address.toHex()} |  sta  P8ESTACK_LO,x |  dex")
             }
             is IdentifierReference -> {
                 // the identifier is a pointer variable, so read the value from the address in it
-                val sourceName = asmgen.asmIdentifierName(expr.addressExpression as IdentifierReference)
-                asmgen.out("""
-        lda  $sourceName
-        sta  (+) +1
-        lda  $sourceName+1
-        sta  (+) +2
-+       lda  ${'$'}ffff     ; modified
-        sta  $ESTACK_LO_HEX,x
-        dex""")
+                asmgen.loadByteFromPointerIntoA(expr.addressExpression as IdentifierReference)
+                asmgen.out(" sta  P8ESTACK_LO,x |  dex")
             }
             else -> {
                 translateExpression(expr.addressExpression)
-                asmgen.out("  jsr  prog8_lib.read_byte_from_address")
-                asmgen.out("  sta  $ESTACK_LO_PLUS1_HEX,x")
+                asmgen.out("  jsr  prog8_lib.read_byte_from_address_on_stack")
+                asmgen.out("  sta  P8ESTACK_LO+1,x")
             }
         }
     }
 
     private fun translateExpression(expr: NumericLiteralValue) {
         when(expr.type) {
-            DataType.UBYTE, DataType.BYTE -> asmgen.out(" lda  #${expr.number.toHex()}  | sta  $ESTACK_LO_HEX,x  | dex")
+            DataType.UBYTE, DataType.BYTE -> asmgen.out(" lda  #${expr.number.toHex()}  | sta  P8ESTACK_LO,x  | dex")
             DataType.UWORD, DataType.WORD -> asmgen.out("""
                 lda  #<${expr.number.toHex()}
-                sta  $ESTACK_LO_HEX,x
+                sta  P8ESTACK_LO,x
                 lda  #>${expr.number.toHex()}
-                sta  $ESTACK_HI_HEX,x
+                sta  P8ESTACK_HI,x
                 dex
             """)
             DataType.FLOAT -> {
-                val floatConst = asmgen.getFloatConst(expr.number.toDouble())
+                val floatConst = asmgen.getFloatAsmConst(expr.number.toDouble())
                 asmgen.out(" lda  #<$floatConst |  ldy  #>$floatConst |  jsr  c64flt.push_float")
             }
             else -> throw AssemblyError("weird type")
@@ -174,28 +189,24 @@ internal class ExpressionsAsmGen(private val program: Program, private val asmge
     }
 
     private fun translateExpression(expr: IdentifierReference) {
-        val varname = asmgen.asmIdentifierName(expr)
+        val varname = asmgen.asmVariableName(expr)
         when(expr.inferType(program).typeOrElse(DataType.STRUCT)) {
             DataType.UBYTE, DataType.BYTE -> {
-                asmgen.out("  lda  $varname  |  sta  $ESTACK_LO_HEX,x  |  dex")
+                asmgen.out("  lda  $varname  |  sta  P8ESTACK_LO,x  |  dex")
             }
             DataType.UWORD, DataType.WORD -> {
-                asmgen.out("  lda  $varname  |  sta  $ESTACK_LO_HEX,x  |  lda  $varname+1 |  sta  $ESTACK_HI_HEX,x |  dex")
+                asmgen.out("  lda  $varname  |  sta  P8ESTACK_LO,x  |  lda  $varname+1 |  sta  P8ESTACK_HI,x |  dex")
             }
             DataType.FLOAT -> {
                 asmgen.out(" lda  #<$varname |  ldy  #>$varname|  jsr  c64flt.push_float")
             }
             in IterableDatatypes -> {
-                asmgen.out("  lda  #<$varname  |  sta  $ESTACK_LO_HEX,x  |  lda  #>$varname |  sta  $ESTACK_HI_HEX,x |  dex")
+                asmgen.out("  lda  #<$varname  |  sta  P8ESTACK_LO,x  |  lda  #>$varname |  sta  P8ESTACK_HI,x |  dex")
             }
             else -> throw AssemblyError("stack push weird variable type $expr")
         }
     }
 
-    private val optimizedByteMultiplications = setOf(3,5,6,7,9,10,11,12,13,14,15,20,25,40)
-    private val optimizedWordMultiplications = setOf(3,5,6,7,9,10,12,15,20,25,40)
-    private val powersOfTwo = setOf(0,1,2,4,8,16,32,64,128,256)
-
     private fun translateExpression(expr: BinaryExpression) {
         val leftIDt = expr.left.inferType(program)
         val rightIDt = expr.right.inferType(program)
@@ -207,79 +218,80 @@ internal class ExpressionsAsmGen(private val program: Program, private val asmge
         // see if we can apply some optimized routines
         when(expr.operator) {
             ">>" -> {
-                // bit-shifts are always by a constant number (for now)
                 translateExpression(expr.left)
-                val amount = expr.right.constValue(program)!!.number.toInt()
-                when (leftDt) {
-                    DataType.UBYTE -> {
-                        if(amount<=2)
-                            repeat(amount) { asmgen.out(" lsr  $ESTACK_LO_PLUS1_HEX,x") }
-                        else {
-                            asmgen.out(" lda  $ESTACK_LO_PLUS1_HEX,x")
-                            repeat(amount) { asmgen.out(" lsr  a") }
-                            asmgen.out(" sta  $ESTACK_LO_PLUS1_HEX,x")
+                val amount = expr.right.constValue(program)?.number?.toInt()
+                if(amount!=null) {
+                    when (leftDt) {
+                        DataType.UBYTE -> {
+                            if (amount <= 2)
+                                repeat(amount) { asmgen.out(" lsr  P8ESTACK_LO+1,x") }
+                            else {
+                                asmgen.out(" lda  P8ESTACK_LO+1,x")
+                                repeat(amount) { asmgen.out(" lsr  a") }
+                                asmgen.out(" sta  P8ESTACK_LO+1,x")
+                            }
                         }
-                    }
-                    DataType.BYTE -> {
-                        if(amount<=2)
-                            repeat(amount) { asmgen.out(" lda  $ESTACK_LO_PLUS1_HEX,x |  asl  a |  ror  $ESTACK_LO_PLUS1_HEX,x") }
-                        else {
-                            asmgen.out(" lda  $ESTACK_LO_PLUS1_HEX,x |  sta  ${C64MachineDefinition.C64Zeropage.SCRATCH_B1}")
-                            repeat(amount) { asmgen.out(" asl  a |  ror  ${C64MachineDefinition.C64Zeropage.SCRATCH_B1} |  lda  ${C64MachineDefinition.C64Zeropage.SCRATCH_B1}") }
-                            asmgen.out(" sta  $ESTACK_LO_PLUS1_HEX,x")
+                        DataType.BYTE -> {
+                            if (amount <= 2)
+                                repeat(amount) { asmgen.out(" lda  P8ESTACK_LO+1,x |  asl  a |  ror  P8ESTACK_LO+1,x") }
+                            else {
+                                asmgen.out(" lda  P8ESTACK_LO+1,x |  sta  P8ZP_SCRATCH_B1")
+                                repeat(amount) { asmgen.out(" asl  a |  ror  P8ZP_SCRATCH_B1 |  lda  P8ZP_SCRATCH_B1") }
+                                asmgen.out(" sta  P8ESTACK_LO+1,x")
+                            }
                         }
-                    }
-                    DataType.UWORD -> {
-                        var left = amount
-                        while(left>=7) {
-                            asmgen.out(" jsr  math.shift_right_uw_7")
-                            left -= 7
+                        DataType.UWORD -> {
+                            var left = amount
+                            while (left >= 7) {
+                                asmgen.out(" jsr  math.shift_right_uw_7")
+                                left -= 7
+                            }
+                            if (left in 0..2)
+                                repeat(left) { asmgen.out(" lsr  P8ESTACK_HI+1,x |  ror  P8ESTACK_LO+1,x") }
+                            else
+                                asmgen.out(" jsr  math.shift_right_uw_$left")
                         }
-                        if (left in 0..2)
-                            repeat(left) { asmgen.out(" lsr  $ESTACK_HI_PLUS1_HEX,x |  ror  $ESTACK_LO_PLUS1_HEX,x") }
-                        else
-                            asmgen.out(" jsr  math.shift_right_uw_$left")
-                    }
-                    DataType.WORD -> {
-                        var left = amount
-                        while(left>=7) {
-                            asmgen.out(" jsr  math.shift_right_w_7")
-                            left -= 7
+                        DataType.WORD -> {
+                            var left = amount
+                            while (left >= 7) {
+                                asmgen.out(" jsr  math.shift_right_w_7")
+                                left -= 7
+                            }
+                            if (left in 0..2)
+                                repeat(left) { asmgen.out(" lda  P8ESTACK_HI+1,x |  asl a  |  ror  P8ESTACK_HI+1,x |  ror  P8ESTACK_LO+1,x") }
+                            else
+                                asmgen.out(" jsr  math.shift_right_w_$left")
                         }
-                        if (left in 0..2)
-                            repeat(left) { asmgen.out(" lda  $ESTACK_HI_PLUS1_HEX,x |  asl a  |  ror  $ESTACK_HI_PLUS1_HEX,x |  ror  $ESTACK_LO_PLUS1_HEX,x") }
-                        else
-                            asmgen.out(" jsr  math.shift_right_w_$left")
+                        else -> throw AssemblyError("weird type")
                     }
-                    else -> throw AssemblyError("weird type")
+                    return
                 }
-                return
             }
             "<<" -> {
-                // bit-shifts are always by a constant number (for now)
                 translateExpression(expr.left)
-                val amount = expr.right.constValue(program)!!.number.toInt()
-                if (leftDt in ByteDatatypes) {
-                    if(amount<=2)
-                        repeat(amount) { asmgen.out("  asl  $ESTACK_LO_PLUS1_HEX,x") }
-                    else {
-                        asmgen.out("  lda  $ESTACK_LO_PLUS1_HEX,x")
-                        repeat(amount) { asmgen.out("  asl  a") }
-                        asmgen.out("  sta  $ESTACK_LO_PLUS1_HEX,x")
+                val amount = expr.right.constValue(program)?.number?.toInt()
+                if(amount!=null) {
+                    if (leftDt in ByteDatatypes) {
+                        if (amount <= 2)
+                            repeat(amount) { asmgen.out("  asl  P8ESTACK_LO+1,x") }
+                        else {
+                            asmgen.out("  lda  P8ESTACK_LO+1,x")
+                            repeat(amount) { asmgen.out("  asl  a") }
+                            asmgen.out("  sta  P8ESTACK_LO+1,x")
+                        }
+                    } else {
+                        var left = amount
+                        while (left >= 7) {
+                            asmgen.out(" jsr  math.shift_left_w_7")
+                            left -= 7
+                        }
+                        if (left in 0..2)
+                            repeat(left) { asmgen.out("  asl  P8ESTACK_LO+1,x |  rol  P8ESTACK_HI+1,x") }
+                        else
+                            asmgen.out(" jsr  math.shift_left_w_$left")
                     }
+                    return
                 }
-                else {
-                    var left=amount
-                    while(left>=7) {
-                        asmgen.out(" jsr  math.shift_left_w_7")
-                        left -= 7
-                    }
-                    if (left in 0..2)
-                        repeat(left) { asmgen.out("  asl  $ESTACK_LO_PLUS1_HEX,x |  rol  $ESTACK_HI_PLUS1_HEX,x") }
-                    else
-                        asmgen.out(" jsr  math.shift_left_w_$left")
-                }
-                return
             }
             "*" -> {
                 val value = expr.right.constValue(program)
@@ -288,40 +300,40 @@ internal class ExpressionsAsmGen(private val program: Program, private val asmge
                         val amount = value.number.toInt()
                         when(rightDt) {
                             DataType.UBYTE -> {
-                                if(amount in optimizedByteMultiplications) {
+                                if(amount in asmgen.optimizedByteMultiplications) {
                                     translateExpression(expr.left)
-                                    asmgen.out(" jsr  math.mul_byte_$amount")
+                                    asmgen.out(" jsr  math.stack_mul_byte_$amount")
                                     return
                                 }
                             }
                             DataType.BYTE -> {
-                                if(amount in optimizedByteMultiplications) {
+                                if(amount in asmgen.optimizedByteMultiplications) {
                                     translateExpression(expr.left)
-                                    asmgen.out(" jsr  math.mul_byte_$amount")
+                                    asmgen.out(" jsr  math.stack_mul_byte_$amount")
                                     return
                                 }
-                                if(amount.absoluteValue in optimizedByteMultiplications) {
+                                if(amount.absoluteValue in asmgen.optimizedByteMultiplications) {
                                     translateExpression(expr.left)
-                                    asmgen.out(" jsr  prog8_lib.neg_b |  jsr  math.mul_byte_${amount.absoluteValue}")
+                                    asmgen.out(" jsr  prog8_lib.neg_b |  jsr  math.stack_mul_byte_${amount.absoluteValue}")
                                     return
                                 }
                             }
                             DataType.UWORD -> {
-                                if(amount in optimizedWordMultiplications) {
+                                if(amount in asmgen.optimizedWordMultiplications) {
                                     translateExpression(expr.left)
-                                    asmgen.out(" jsr  math.mul_word_$amount")
+                                    asmgen.out(" jsr  math.stack_mul_word_$amount")
                                     return
                                 }
                             }
                             DataType.WORD -> {
-                                if(amount in optimizedWordMultiplications) {
+                                if(amount in asmgen.optimizedWordMultiplications) {
                                     translateExpression(expr.left)
-                                    asmgen.out(" jsr  math.mul_word_$amount")
+                                    asmgen.out(" jsr  math.stack_mul_word_$amount")
                                     return
                                 }
-                                if(amount.absoluteValue in optimizedWordMultiplications) {
+                                if(amount.absoluteValue in asmgen.optimizedWordMultiplications) {
                                     translateExpression(expr.left)
-                                    asmgen.out(" jsr  prog8_lib.neg_w |  jsr  math.mul_word_${amount.absoluteValue}")
+                                    asmgen.out(" jsr  prog8_lib.neg_w |  jsr  math.stack_mul_word_${amount.absoluteValue}")
                                     return
                                 }
                             }
@@ -364,9 +376,9 @@ internal class ExpressionsAsmGen(private val program: Program, private val asmge
                 when(type) {
                     in ByteDatatypes ->
                         asmgen.out("""
-                            lda  $ESTACK_LO_PLUS1_HEX,x
+                            lda  P8ESTACK_LO+1,x
                             eor  #255
-                            sta  $ESTACK_LO_PLUS1_HEX,x
+                            sta  P8ESTACK_LO+1,x
                             """)
                     in WordDatatypes -> asmgen.out("  jsr  prog8_lib.inv_word")
                     else -> throw AssemblyError("weird type")
@@ -383,29 +395,47 @@ internal class ExpressionsAsmGen(private val program: Program, private val asmge
         }
     }
 
-    private fun translatePushFromArray(arrayExpr: ArrayIndexedExpression) {
-        // assume *reading* from an array
+    private fun translateExpression(arrayExpr: ArrayIndexedExpression) {
         val index = arrayExpr.arrayspec.index
-        val arrayDt = arrayExpr.identifier.targetVarDecl(program.namespace)!!.datatype
-        val arrayVarName = asmgen.asmIdentifierName(arrayExpr.identifier)
+        val elementDt = arrayExpr.inferType(program).typeOrElse(DataType.STRUCT)
+        val arrayVarName = asmgen.asmVariableName(arrayExpr.identifier)
         if(index is NumericLiteralValue) {
-            val elementDt = ArrayElementTypes.getValue(arrayDt)
             val indexValue = index.number.toInt() * elementDt.memorySize()
             when(elementDt) {
                 in ByteDatatypes -> {
-                    asmgen.out("  lda  $arrayVarName+$indexValue |  sta  $ESTACK_LO_HEX,x |  dex")
+                    asmgen.out("  lda  $arrayVarName+$indexValue |  sta  P8ESTACK_LO,x |  dex")
                 }
                 in WordDatatypes -> {
-                    asmgen.out("  lda  $arrayVarName+$indexValue |  sta  $ESTACK_LO_HEX,x |  lda  $arrayVarName+$indexValue+1 |  sta  $ESTACK_HI_HEX,x |  dex")
+                    asmgen.out("  lda  $arrayVarName+$indexValue |  sta  P8ESTACK_LO,x |  lda  $arrayVarName+$indexValue+1 |  sta  P8ESTACK_HI,x |  dex")
                 }
                 DataType.FLOAT -> {
                     asmgen.out("  lda  #<$arrayVarName+$indexValue |  ldy  #>$arrayVarName+$indexValue |  jsr  c64flt.push_float")
                 }
-                else -> throw AssemblyError("weird type")
+                else -> throw AssemblyError("weird element type")
             }
         } else {
-            asmgen.translateArrayIndexIntoA(arrayExpr)
-            asmgen.readAndPushArrayvalueWithIndexA(arrayDt, arrayExpr.identifier)
+            when(elementDt) {
+                in ByteDatatypes -> {
+                    asmgen.loadScaledArrayIndexIntoRegister(arrayExpr, elementDt, CpuRegister.Y)
+                    asmgen.out(" lda  $arrayVarName,y |  sta  P8ESTACK_LO,x |  dex")
+                }
+                in WordDatatypes -> {
+                    asmgen.loadScaledArrayIndexIntoRegister(arrayExpr, elementDt, CpuRegister.Y)
+                    asmgen.out(" lda  $arrayVarName,y |  sta  P8ESTACK_LO,x |  lda  $arrayVarName+1,y |  sta  P8ESTACK_HI,x |  dex")
+                }
+                DataType.FLOAT -> {
+                    asmgen.loadScaledArrayIndexIntoRegister(arrayExpr, elementDt, CpuRegister.A)
+                    asmgen.out("""
+                        ldy  #>$arrayVarName
+                        clc
+                        adc  #<$arrayVarName
+                        bcc  +
+                        iny
++                       jsr  c64flt.push_float""")
+                }
+                else -> throw AssemblyError("weird dt")
+            }
+
         }
     }
 
@@ -420,20 +450,21 @@ internal class ExpressionsAsmGen(private val program: Program, private val asmge
                 asmgen.out("  jsr prog8_lib.remainder_ub")
             }
             "+" -> asmgen.out("""
-                lda  $ESTACK_LO_PLUS2_HEX,x
+                lda  P8ESTACK_LO+2,x
                 clc
-                adc  $ESTACK_LO_PLUS1_HEX,x
+                adc  P8ESTACK_LO+1,x
                 inx
-                sta  $ESTACK_LO_PLUS1_HEX,x
+                sta  P8ESTACK_LO+1,x
                 """)
             "-" -> asmgen.out("""
-                lda  $ESTACK_LO_PLUS2_HEX,x
+                lda  P8ESTACK_LO+2,x
                 sec
-                sbc  $ESTACK_LO_PLUS1_HEX,x
+                sbc  P8ESTACK_LO+1,x
                 inx
-                sta  $ESTACK_LO_PLUS1_HEX,x
+                sta  P8ESTACK_LO+1,x
                 """)
-            "<<", ">>" -> throw AssemblyError("bit-shifts not via stack")
+            "<<" -> asmgen.out("  jsr  prog8_lib.shiftleft_b")
+            ">>" -> asmgen.out("  jsr  prog8_lib.shiftright_b")
             "<" -> asmgen.out(if(types==DataType.UBYTE) "  jsr  prog8_lib.less_ub" else "  jsr  prog8_lib.less_b")
             ">" -> asmgen.out(if(types==DataType.UBYTE) "  jsr  prog8_lib.greater_ub" else "  jsr  prog8_lib.greater_b")
             "<=" -> asmgen.out(if(types==DataType.UBYTE) "  jsr  prog8_lib.lesseq_ub" else "  jsr  prog8_lib.lesseq_b")

compiler/src/prog8/compiler/target/c64/codegen/ForLoopsAsmGen.kt

@@ -4,20 +4,15 @@ import prog8.ast.Program
 import prog8.ast.base.DataType
 import prog8.ast.expressions.IdentifierReference
 import prog8.ast.expressions.RangeExpr
-import prog8.ast.statements.AssignTarget
-import prog8.ast.statements.Assignment
 import prog8.ast.statements.ForLoop
 import prog8.compiler.AssemblyError
-import prog8.compiler.target.c64.C64MachineDefinition.ESTACK_HI_PLUS1_HEX
-import prog8.compiler.target.c64.C64MachineDefinition.ESTACK_LO_HEX
-import prog8.compiler.target.c64.C64MachineDefinition.ESTACK_LO_PLUS1_HEX
+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.toHex
 import kotlin.math.absoluteValue
 
-// todo choose more efficient comparisons to avoid needless lda's
-// todo optimize common case when step == 2 or -2
-
-
 internal class ForLoopsAsmGen(private val program: Program, private val asmgen: AsmGen) {
 
     internal fun translate(stmt: ForLoop) {
@@ -43,57 +38,61 @@ internal class ForLoopsAsmGen(private val program: Program, private val asmgen:
     private fun translateForOverNonconstRange(stmt: ForLoop, iterableDt: DataType, range: RangeExpr) {
         val loopLabel = asmgen.makeLabel("for_loop")
         val endLabel = asmgen.makeLabel("for_end")
-        val continueLabel = asmgen.makeLabel("for_continue")
+        val modifiedLabel = asmgen.makeLabel("for_modified")
+        val modifiedLabel2 = asmgen.makeLabel("for_modifiedb")
         asmgen.loopEndLabels.push(endLabel)
-        asmgen.loopContinueLabels.push(continueLabel)
         val stepsize=range.step.constValue(program)!!.number.toInt()
         when(iterableDt) {
             DataType.ARRAY_B, DataType.ARRAY_UB -> {
                 if (stepsize==1 || stepsize==-1) {
 
-                    // bytes, step 1 or -1
+                    // bytes array, step 1 or -1
 
                     val incdec = if(stepsize==1) "inc" else "dec"
                     // loop over byte range via loopvar
-                    val varname = asmgen.asmIdentifierName(stmt.loopVar)
+                    val varname = asmgen.asmVariableName(stmt.loopVar)
                     asmgen.translateExpression(range.to)
                     asmgen.translateExpression(range.from)
                     asmgen.out("""
                 inx
-                lda  ${ESTACK_LO_HEX},x
+                lda  P8ESTACK_LO,x
                 sta  $varname
+                lda  P8ESTACK_LO+1,x
+                sta  $modifiedLabel+1
 $loopLabel""")
                         asmgen.translate(stmt.body)
                         asmgen.out("""
-$continueLabel  lda  $varname
-                cmp  $ESTACK_LO_PLUS1_HEX,x
+                lda  $varname
+$modifiedLabel  cmp  #0         ; modified 
                 beq  $endLabel
                 $incdec  $varname
                 jmp  $loopLabel
 $endLabel       inx""")
-                }
-                else {
+
+                } else {
 
                     // bytes, step >= 2 or <= -2
 
                     // loop over byte range via loopvar
-                    val varname = asmgen.asmIdentifierName(stmt.loopVar)
+                    val varname = asmgen.asmVariableName(stmt.loopVar)
                     asmgen.translateExpression(range.to)
                     asmgen.translateExpression(range.from)
                     asmgen.out("""
                 inx
-                lda  ${ESTACK_LO_HEX},x
+                lda  P8ESTACK_LO,x
                 sta  $varname
+                lda  P8ESTACK_LO+1,x
+                sta  $modifiedLabel+1
 $loopLabel""")
                     asmgen.translate(stmt.body)
                     asmgen.out("""
-$continueLabel  lda  $varname""")
+                lda  $varname""")
                     if(stepsize>0) {
                         asmgen.out("""
                 clc
                 adc  #$stepsize
                 sta  $varname
-                cmp  $ESTACK_LO_PLUS1_HEX,x
+$modifiedLabel  cmp  #0    ; modified
                 bcc  $loopLabel
                 beq  $loopLabel""")
                     } else {
@@ -101,7 +100,7 @@ $continueLabel  lda  $varname""")
                 sec
                 sbc  #${stepsize.absoluteValue}
                 sta  $varname
-                cmp  $ESTACK_LO_PLUS1_HEX,x
+$modifiedLabel  cmp  #0     ; modified 
                 bcs  $loopLabel""")
                     }
                     asmgen.out("""
@@ -115,47 +114,52 @@ $endLabel       inx""")
 
                     stepsize == 1 || stepsize == -1 -> {
                         asmgen.translateExpression(range.to)
-                        val varname = asmgen.asmIdentifierName(stmt.loopVar)
-                        val assignLoopvar = Assignment(AssignTarget(stmt.loopVar, null, null, stmt.loopVar.position),
-                                null, range.from, range.position)
-                        assignLoopvar.linkParents(stmt)
-                        asmgen.translate(assignLoopvar)
-                        asmgen.out(loopLabel)
+                        assignLoopvar(stmt, range)
+                        val varname = asmgen.asmVariableName(stmt.loopVar)
+                        asmgen.out("""
+                            lda  P8ESTACK_HI+1,x
+                            sta  $modifiedLabel+1
+                            lda  P8ESTACK_LO+1,x
+                            sta  $modifiedLabel2+1
+$loopLabel""")
                         asmgen.translate(stmt.body)
                         asmgen.out("""
                 lda  $varname+1
-                cmp  $ESTACK_HI_PLUS1_HEX,x
+$modifiedLabel  cmp  #0    ; modified 
                 bne  +
                 lda  $varname
-                cmp  $ESTACK_LO_PLUS1_HEX,x
+$modifiedLabel2 cmp  #0    ; modified 
                 beq  $endLabel""")
                         if(stepsize==1) {
                             asmgen.out("""
 +               inc  $varname
-                bne  +
-                inc  $varname+1            
+                bne  $loopLabel
+                inc  $varname+1
+                jmp  $loopLabel
                             """)
                         } else {
                             asmgen.out("""
 +               lda  $varname
                 bne  +
                 dec  $varname+1
-+               dec  $varname""")
++               dec  $varname
+                jmp  $loopLabel""")
                         }
-                        asmgen.out("""
-+               jmp  $loopLabel
-$endLabel       inx""")
+                        asmgen.out(endLabel)
+                        asmgen.out(" inx")
                     }
                     stepsize > 0 -> {
 
                         // (u)words, step >= 2
-
                         asmgen.translateExpression(range.to)
-                        val varname = asmgen.asmIdentifierName(stmt.loopVar)
-                        val assignLoopvar = Assignment(AssignTarget(stmt.loopVar, null, null, stmt.loopVar.position),
-                                null, range.from, range.position)
-                        assignLoopvar.linkParents(stmt)
-                        asmgen.translate(assignLoopvar)
+                        asmgen.out("""
+                            lda  P8ESTACK_HI+1,x
+                            sta  $modifiedLabel+1
+                            lda  P8ESTACK_LO+1,x
+                            sta  $modifiedLabel2+1
+                        """)
+                        assignLoopvar(stmt, range)
+                        val varname = asmgen.asmVariableName(stmt.loopVar)
                         asmgen.out(loopLabel)
                         asmgen.translate(stmt.body)
 
@@ -168,12 +172,11 @@ $endLabel       inx""")
                 lda  $varname+1
                 adc  #>$stepsize
                 sta  $varname+1
-                lda  $ESTACK_HI_PLUS1_HEX,x
-                cmp  $varname+1
-                bcc  $endLabel
-                bne  $loopLabel
-                lda  $varname
-                cmp  $ESTACK_LO_PLUS1_HEX,x
+$modifiedLabel  cmp  #0     ; modified
+                bcc  $loopLabel
+                bne  $endLabel
+$modifiedLabel2 lda  #0     ; modified
+                cmp  $varname
                 bcc  $endLabel
                 bcs  $loopLabel
 $endLabel       inx""")
@@ -186,9 +189,9 @@ $endLabel       inx""")
                 lda  $varname+1
                 adc  #>$stepsize
                 sta  $varname+1
-                lda  $ESTACK_LO_PLUS1_HEX,x
+$modifiedLabel2 lda  #0   ; modified
                 cmp  $varname
-                lda  $ESTACK_HI_PLUS1_HEX,x
+$modifiedLabel  lda  #0   ; modified
                 sbc  $varname+1
                 bvc  +
                 eor  #$80
@@ -200,11 +203,14 @@ $endLabel       inx""")
 
                         // (u)words, step <= -2
                         asmgen.translateExpression(range.to)
-                        val varname = asmgen.asmIdentifierName(stmt.loopVar)
-                        val assignLoopvar = Assignment(AssignTarget(stmt.loopVar, null, null, stmt.loopVar.position),
-                                null, range.from, range.position)
-                        assignLoopvar.linkParents(stmt)
-                        asmgen.translate(assignLoopvar)
+                        asmgen.out("""
+                            lda  P8ESTACK_HI+1,x
+                            sta  $modifiedLabel+1
+                            lda  P8ESTACK_LO+1,x
+                            sta  $modifiedLabel2+1
+                        """)
+                        assignLoopvar(stmt, range)
+                        val varname = asmgen.asmVariableName(stmt.loopVar)
                         asmgen.out(loopLabel)
                         asmgen.translate(stmt.body)
 
@@ -217,11 +223,11 @@ $endLabel       inx""")
                 lda  $varname+1
                 sbc  #>${stepsize.absoluteValue}
                 sta  $varname+1
-                cmp  $ESTACK_HI_PLUS1_HEX,x
+$modifiedLabel  cmp  #0    ; modified                
                 bcc  $endLabel
                 bne  $loopLabel
                 lda  $varname
-                cmp  $ESTACK_LO_PLUS1_HEX,x
+$modifiedLabel2 cmp  #0    ; modified 
                 bcs  $loopLabel
 $endLabel       inx""")
                         } else {
@@ -235,9 +241,9 @@ $endLabel       inx""")
                 sbc  #>${stepsize.absoluteValue}
                 sta  $varname+1
                 pla
-                cmp  $ESTACK_LO_PLUS1_HEX,x
+$modifiedLabel2 cmp  #0    ; modified 
                 lda  $varname+1
-                sbc  $ESTACK_HI_PLUS1_HEX,x
+$modifiedLabel  sbc  #0    ; modified
                 bvc  +
                 eor  #$80
 +               bpl  $loopLabel                
@@ -250,16 +256,13 @@ $endLabel       inx""")
         }
 
         asmgen.loopEndLabels.pop()
-        asmgen.loopContinueLabels.pop()
     }
 
     private fun translateForOverIterableVar(stmt: ForLoop, iterableDt: DataType, ident: IdentifierReference) {
         val loopLabel = asmgen.makeLabel("for_loop")
         val endLabel = asmgen.makeLabel("for_end")
-        val continueLabel = asmgen.makeLabel("for_continue")
         asmgen.loopEndLabels.push(endLabel)
-        asmgen.loopContinueLabels.push(continueLabel)
-        val iterableName = asmgen.asmIdentifierName(ident)
+        val iterableName = asmgen.asmVariableName(ident)
         val decl = ident.targetVarDecl(program.namespace)!!
         when(iterableDt) {
             DataType.STR -> {
@@ -269,72 +272,88 @@ $endLabel       inx""")
                     sta  $loopLabel+1
                     sty  $loopLabel+2
 $loopLabel          lda  ${65535.toHex()}       ; modified
-                    beq  $endLabel""")
-                asmgen.out("  sta  ${asmgen.asmIdentifierName(stmt.loopVar)}")
+                    beq  $endLabel
+                    sta  ${asmgen.asmVariableName(stmt.loopVar)}""")
                 asmgen.translate(stmt.body)
                 asmgen.out("""
-$continueLabel      inc  $loopLabel+1
+                    inc  $loopLabel+1
                     bne  $loopLabel
                     inc  $loopLabel+2
                     bne  $loopLabel
 $endLabel""")
             }
             DataType.ARRAY_UB, DataType.ARRAY_B -> {
-                // TODO: optimize loop code when the length of the array is < 256, don't need a separate counter var in such cases
-                val length = decl.arraysize!!.size()!!
-                val counterLabel = asmgen.makeLabel("for_counter")
-                val modifiedLabel = asmgen.makeLabel("for_modified")
+                val length = decl.arraysize!!.constIndex()!!
+                val indexVar = asmgen.makeLabel("for_index")
                 asmgen.out("""
-                    lda  #<$iterableName
-                    ldy  #>$iterableName
-                    sta  $modifiedLabel+1
-                    sty  $modifiedLabel+2
                     ldy  #0
-$loopLabel          sty  $counterLabel
-$modifiedLabel      lda  ${65535.toHex()},y       ; modified""")
-                asmgen.out("  sta  ${asmgen.asmIdentifierName(stmt.loopVar)}")
+$loopLabel          sty  $indexVar
+                    lda  $iterableName,y
+                    sta  ${asmgen.asmVariableName(stmt.loopVar)}""")
                 asmgen.translate(stmt.body)
-                asmgen.out("""
-$continueLabel      ldy  $counterLabel
-                    iny
-                    cpy  #${length and 255}
-                    beq  $endLabel
-                    jmp  $loopLabel
-$counterLabel       .byte  0
-$endLabel""")
+                if(length<=255) {
+                    asmgen.out("""
+                        ldy  $indexVar
+                        iny
+                        cpy  #$length
+                        beq  $endLabel
+                        bne  $loopLabel""")
+                } else {
+                    // length is 256
+                    asmgen.out("""
+                        ldy  $indexVar
+                        iny
+                        bne  $loopLabel
+                        beq  $endLabel""")
+                }
+                if(length>=16 && asmgen.zeropage.available() > 0) {
+                    // allocate index var on ZP
+                    val zpAddr = asmgen.zeropage.allocate(indexVar, DataType.UBYTE, stmt.position, asmgen.errors)
+                    asmgen.out("""$indexVar = $zpAddr  ; auto zp UBYTE""")
+                } else {
+                    asmgen.out("""
+$indexVar           .byte  0""")
+                }
+                asmgen.out(endLabel)
             }
             DataType.ARRAY_W, DataType.ARRAY_UW -> {
-                // TODO: optimize loop code when the length of the array is < 256, don't need a separate counter var in such cases
-                val length = decl.arraysize!!.size()!! * 2
-                val counterLabel = asmgen.makeLabel("for_counter")
-                val modifiedLabel = asmgen.makeLabel("for_modified")
-                val modifiedLabel2 = asmgen.makeLabel("for_modified2")
-                val loopvarName = asmgen.asmIdentifierName(stmt.loopVar)
+                val length = decl.arraysize!!.constIndex()!! * 2
+                val indexVar = asmgen.makeLabel("for_index")
+                val loopvarName = asmgen.asmVariableName(stmt.loopVar)
                 asmgen.out("""
-                    lda  #<$iterableName
-                    ldy  #>$iterableName
-                    sta  $modifiedLabel+1
-                    sty  $modifiedLabel+2
-                    lda  #<$iterableName+1
-                    ldy  #>$iterableName+1
-                    sta  $modifiedLabel2+1
-                    sty  $modifiedLabel2+2
                     ldy  #0
-$loopLabel          sty  $counterLabel
-$modifiedLabel      lda  ${65535.toHex()},y       ; modified
+$loopLabel          sty  $indexVar
+                    lda  $iterableName,y
                     sta  $loopvarName
-$modifiedLabel2     lda  ${65535.toHex()},y       ; modified
+                    lda  $iterableName+1,y
                     sta  $loopvarName+1""")
                 asmgen.translate(stmt.body)
-                asmgen.out("""
-$continueLabel      ldy  $counterLabel
-                    iny
-                    iny
-                    cpy  #${length and 255}
-                    beq  $endLabel
-                    jmp  $loopLabel
-$counterLabel       .byte  0
-$endLabel""")
+                if(length<=127) {
+                    asmgen.out("""
+                        ldy  $indexVar
+                        iny
+                        iny
+                        cpy  #$length
+                        beq  $endLabel
+                        bne  $loopLabel""")
+                } else {
+                    // length is 128 words, 256 bytes
+                    asmgen.out("""
+                        ldy  $indexVar
+                        iny
+                        iny
+                        bne  $loopLabel
+                        beq  $endLabel""")
+                }
+                if(length>=16 && asmgen.zeropage.available() > 0) {
+                    // allocate index var on ZP
+                    val zpAddr = asmgen.zeropage.allocate(indexVar, DataType.UBYTE, stmt.position, asmgen.errors)
+                    asmgen.out("""$indexVar = $zpAddr  ; auto zp UBYTE""")
+                } else {
+                    asmgen.out("""
+$indexVar           .byte  0""")
+                }
+                asmgen.out(endLabel)
             }
             DataType.ARRAY_F -> {
                 throw AssemblyError("for loop with floating point variables is not supported")
@@ -342,205 +361,123 @@ $endLabel""")
             else -> throw AssemblyError("can't iterate over $iterableDt")
         }
         asmgen.loopEndLabels.pop()
-        asmgen.loopContinueLabels.pop()
     }
 
     private fun translateForOverConstRange(stmt: ForLoop, iterableDt: DataType, range: IntProgression) {
-        // TODO: optimize loop code when the range is < 256 iterations, don't need a separate counter var in such cases
-        if (range.isEmpty())
-            throw AssemblyError("empty range")
+        if (range.isEmpty() || range.step==0)
+            throw AssemblyError("empty range or step 0")
+        if(iterableDt==DataType.ARRAY_B || iterableDt==DataType.ARRAY_UB) {
+            if(range.step==1 && range.last>range.first) return translateForSimpleByteRangeAsc(stmt, range)
+            if(range.step==-1 && range.last<range.first) return translateForSimpleByteRangeDesc(stmt, range)
+        }
+        else if(iterableDt==DataType.ARRAY_W || iterableDt==DataType.ARRAY_UW) {
+            if(range.step==1 && range.last>range.first) return translateForSimpleWordRangeAsc(stmt, range)
+            if(range.step==-1 && range.last<range.first) return translateForSimpleWordRangeDesc(stmt, range)
+        }
+
+        // not one of the easy cases, generate more complex code...
         val loopLabel = asmgen.makeLabel("for_loop")
         val endLabel = asmgen.makeLabel("for_end")
-        val continueLabel = asmgen.makeLabel("for_continue")
         asmgen.loopEndLabels.push(endLabel)
-        asmgen.loopContinueLabels.push(continueLabel)
         when(iterableDt) {
             DataType.ARRAY_B, DataType.ARRAY_UB -> {
-                val counterLabel = asmgen.makeLabel("for_counter")
-                // loop over byte range via loopvar
-                val varname = asmgen.asmIdentifierName(stmt.loopVar)
-                when {
-                    range.step==1 -> {
-                        // step = 1
-                        asmgen.out("""
-                lda  #${range.first}
-                sta  $varname
-                lda  #${range.last-range.first+1 and 255}
-                sta  $counterLabel
+                // loop over byte range via loopvar, step >= 2 or <= -2
+                val varname = asmgen.asmVariableName(stmt.loopVar)
+                asmgen.out("""
+                            lda  #${range.first}
+                            sta  $varname
 $loopLabel""")
-                            asmgen.translate(stmt.body)
+                asmgen.translate(stmt.body)
+                when (range.step) {
+                    0, 1, -1 -> {
+                        throw AssemblyError("step 0, 1 and -1 should have been handled specifically  $stmt")
+                    }
+                    2 -> {
+                        if(range.last==255) {
                             asmgen.out("""
-$continueLabel  dec  $counterLabel
-                beq  $endLabel
-                inc  $varname
-                jmp  $loopLabel
-$counterLabel   .byte  0                
-$endLabel""")
+                                inc  $varname
+                                beq  $endLabel
+                                inc  $varname
+                                bne  $loopLabel""")
+                        } else {
+                            asmgen.out("""
+                                lda  $varname
+                                cmp  #${range.last}
+                                beq  $endLabel
+                                inc  $varname
+                                inc  $varname
+                                jmp  $loopLabel""")
+                        }
                     }
-                    range.step==-1 -> {
-                        // step = -1
-                        asmgen.out("""
-                lda  #${range.first}
-                sta  $varname
-                lda  #${range.first-range.last+1 and 255}
-                sta  $counterLabel
-$loopLabel""")
-                        asmgen.translate(stmt.body)
-                        asmgen.out("""
-$continueLabel  dec  $counterLabel
-                beq  $endLabel
-                dec  $varname
-                jmp  $loopLabel
-$counterLabel   .byte  0                
-$endLabel""")
-                    }
-                    range.step >= 2 -> {
-                        // step >= 2
-                        asmgen.out("""
-                lda  #${(range.last-range.first) / range.step + 1}
-                sta  $counterLabel
-                lda  #${range.first}
-                sta  $varname
-$loopLabel""")
-                        asmgen.translate(stmt.body)
-                        asmgen.out("""
-$continueLabel  dec  $counterLabel
-                beq  $endLabel
-                lda  $varname
-                clc
-                adc  #${range.step}
-                sta  $varname
-                jmp  $loopLabel
-$counterLabel   .byte  0                
-$endLabel""")
+                    -2 -> {
+                        when (range.last) {
+                            0 -> asmgen.out("""
+                                lda  $varname
+                                beq  $endLabel
+                                dec  $varname
+                                dec  $varname
+                                jmp  $loopLabel""")
+                            1 -> asmgen.out("""
+                                dec  $varname
+                                beq  $endLabel
+                                dec  $varname
+                                bne  $loopLabel""")
+                            else -> asmgen.out("""
+                                lda  $varname
+                                cmp  #${range.last}
+                                beq  $endLabel
+                                dec  $varname
+                                dec  $varname
+                                jmp  $loopLabel""")
+                        }
                     }
                     else -> {
-                        // step <= -2
+                        // step <= -3 or >= 3
                         asmgen.out("""
-                lda  #${(range.first-range.last) / range.step.absoluteValue + 1}
-                sta  $counterLabel
-                lda  #${range.first}
-                sta  $varname
-$loopLabel""")
-                        asmgen.translate(stmt.body)
-                        asmgen.out("""
-$continueLabel  dec  $counterLabel
-                beq  $endLabel
-                lda  $varname
-                sec
-                sbc  #${range.step.absoluteValue}
-                sta  $varname
-                jmp  $loopLabel
-$counterLabel   .byte  0                
-$endLabel""")
+                            lda  $varname
+                            cmp  #${range.last}
+                            beq  $endLabel
+                            clc
+                            adc  #${range.step}
+                            sta  $varname
+                            jmp  $loopLabel""")
                     }
                 }
+                asmgen.out(endLabel)
             }
             DataType.ARRAY_W, DataType.ARRAY_UW -> {
-                // loop over word range via loopvar
-                val varname = asmgen.asmIdentifierName(stmt.loopVar)
-                when {
-                    range.step == 1 -> {
-                        // word, step = 1
-                        val lastValue = range.last+1
-                        asmgen.out("""
-                lda  #<${range.first}
-                ldy  #>${range.first}
-                sta  $varname
-                sty  $varname+1
-$loopLabel""")
-                        asmgen.translate(stmt.body)
-                        asmgen.out("""
-$continueLabel  inc  $varname
-                bne  +
-                inc  $varname+1
-+               lda  $varname
-                cmp  #<$lastValue
-                bne  +
-                lda  $varname+1
-                cmp  #>$lastValue
-                beq  $endLabel
-+               jmp  $loopLabel
-$endLabel""")
-                    }
-                    range.step == -1 -> {
-                        // word, step = 1
-                        val lastValue = range.last-1
-                        asmgen.out("""
-                lda  #<${range.first}
-                ldy  #>${range.first}
-                sta  $varname
-                sty  $varname+1
-$loopLabel""")
-                        asmgen.translate(stmt.body)
-                        asmgen.out("""
-$continueLabel  lda  $varname
-                bne  +
-                dec  $varname+1
-+               dec  $varname
-                lda  $varname
-                cmp  #<$lastValue
-                bne  +
-                lda  $varname+1
-                cmp  #>$lastValue
-                beq  $endLabel
-+               jmp  $loopLabel
-$endLabel""")
-                    }
-                    range.step >= 2 -> {
-                        // word, step >= 2
-                        // note: range.last has already been adjusted by kotlin itself to actually be the last value of the sequence
-                        val lastValue = range.last+range.step
-                        asmgen.out("""
-                lda  #<${range.first}
-                ldy  #>${range.first}
-                sta  $varname
-                sty  $varname+1
-$loopLabel""")
-                        asmgen.translate(stmt.body)
-                        asmgen.out("""
-$continueLabel  clc
-                lda  $varname
-                adc  #<${range.step}
-                sta  $varname
-                lda  $varname+1
-                adc  #>${range.step}
-                sta  $varname+1
-                lda  $varname
-                cmp  #<$lastValue
-                bne  +
-                lda  $varname+1
-                cmp  #>$lastValue
-                beq  $endLabel
-+               jmp  $loopLabel
-$endLabel""")
+                // loop over word range via loopvar, step >= 2 or <= -2
+                val varname = asmgen.asmVariableName(stmt.loopVar)
+                when (range.step) {
+                    0, 1, -1 -> {
+                        throw AssemblyError("step 0, 1 and -1 should have been handled specifically  $stmt")
                     }
                     else -> {
-                        // step <= -2
+                        // word, step >= 2 or <= -2
                         // note: range.last has already been adjusted by kotlin itself to actually be the last value of the sequence
-                        val lastValue = range.last+range.step
                         asmgen.out("""
-                lda  #<${range.first}
-                ldy  #>${range.first}
-                sta  $varname
-                sty  $varname+1
+                            lda  #<${range.first}
+                            ldy  #>${range.first}
+                            sta  $varname
+                            sty  $varname+1
 $loopLabel""")
                         asmgen.translate(stmt.body)
                         asmgen.out("""
-$continueLabel  sec
-                lda  $varname
-                sbc  #<${range.step.absoluteValue}
-                sta  $varname
-                lda  $varname+1
-                sbc  #>${range.step.absoluteValue}
-                sta  $varname+1
-                lda  $varname
-                cmp  #<$lastValue
-                bne  +
-                lda  $varname+1
-                cmp  #>$lastValue
-                beq  $endLabel
-+               jmp  $loopLabel
+                            lda  $varname
+                            cmp  #<${range.last}
+                            bne  +
+                            lda  $varname+1
+                            cmp  #>${range.last}
+                            bne  +
+                            beq  $endLabel
++                           lda  $varname
+                            clc
+                            adc  #<${range.step}
+                            sta  $varname
+                            lda  $varname+1
+                            adc  #>${range.step}
+                            sta  $varname+1
+                            jmp  $loopLabel
 $endLabel""")
                     }
                 }
@@ -548,7 +485,134 @@ $endLabel""")
             else -> throw AssemblyError("range expression can only be byte or word")
         }
         asmgen.loopEndLabels.pop()
-        asmgen.loopContinueLabels.pop()
     }
 
+    private fun translateForSimpleByteRangeAsc(stmt: ForLoop, range: IntProgression) {
+        val loopLabel = asmgen.makeLabel("for_loop")
+        val endLabel = asmgen.makeLabel("for_end")
+        asmgen.loopEndLabels.push(endLabel)
+        val varname = asmgen.asmVariableName(stmt.loopVar)
+        asmgen.out("""
+                lda  #${range.first}
+                sta  $varname
+$loopLabel""")
+        asmgen.translate(stmt.body)
+        if (range.last == 255) {
+            asmgen.out("""
+                inc  $varname
+                bne  $loopLabel
+$endLabel""")
+        } else {
+            asmgen.out("""
+                lda  $varname
+                cmp  #${range.last}
+                beq  $endLabel
+                inc  $varname
+                jmp  $loopLabel
+$endLabel""")
+        }
+        asmgen.loopEndLabels.pop()
+    }
+
+    private fun translateForSimpleByteRangeDesc(stmt: ForLoop, range: IntProgression) {
+        val loopLabel = asmgen.makeLabel("for_loop")
+        val endLabel = asmgen.makeLabel("for_end")
+        asmgen.loopEndLabels.push(endLabel)
+        val varname = asmgen.asmVariableName(stmt.loopVar)
+        asmgen.out("""
+                    lda  #${range.first}
+                    sta  $varname
+$loopLabel""")
+        asmgen.translate(stmt.body)
+        when (range.last) {
+            0 -> {
+                asmgen.out("""
+                    lda  $varname
+                    beq  $endLabel
+                    dec  $varname
+                    jmp  $loopLabel
+$endLabel""")
+            }
+            1 -> {
+                asmgen.out("""
+                    dec  $varname
+                    jmp  $loopLabel
+$endLabel""")
+            }
+            else -> {
+                asmgen.out("""
+                    lda  $varname
+                    cmp  #${range.last}
+                    beq  $endLabel
+                    dec  $varname
+                    jmp  $loopLabel
+$endLabel""")
+            }
+        }
+        asmgen.loopEndLabels.pop()
+    }
+
+    private fun translateForSimpleWordRangeAsc(stmt: ForLoop, range: IntProgression) {
+        val loopLabel = asmgen.makeLabel("for_loop")
+        val endLabel = asmgen.makeLabel("for_end")
+        asmgen.loopEndLabels.push(endLabel)
+        val varname = asmgen.asmVariableName(stmt.loopVar)
+        asmgen.out("""
+            lda  #<${range.first}
+            ldy  #>${range.first}
+            sta  $varname
+            sty  $varname+1
+$loopLabel""")
+        asmgen.translate(stmt.body)
+        asmgen.out("""
+            lda  $varname
+            cmp  #<${range.last}
+            bne  +
+            lda  $varname+1
+            cmp  #>${range.last}
+            bne  +
+            beq  $endLabel
++           inc  $varname
+            bne  $loopLabel
+            inc  $varname+1
+            jmp  $loopLabel
+$endLabel""")
+        asmgen.loopEndLabels.pop()
+    }
+
+    private fun translateForSimpleWordRangeDesc(stmt: ForLoop, range: IntProgression) {
+        val loopLabel = asmgen.makeLabel("for_loop")
+        val endLabel = asmgen.makeLabel("for_end")
+        asmgen.loopEndLabels.push(endLabel)
+        val varname = asmgen.asmVariableName(stmt.loopVar)
+        asmgen.out("""
+            lda  #<${range.first}
+            ldy  #>${range.first}
+            sta  $varname
+            sty  $varname+1
+$loopLabel""")
+        asmgen.translate(stmt.body)
+        asmgen.out("""
+            lda  $varname
+            cmp  #<${range.last}
+            bne  +
+            lda  $varname+1
+            cmp  #>${range.last}
+            bne  +
+            beq  $endLabel
++           lda  $varname
+            bne  +
+            dec  $varname+1
++           dec  $varname
+            jmp  $loopLabel
+$endLabel""")
+        asmgen.loopEndLabels.pop()
+    }
+
+    private fun assignLoopvar(stmt: ForLoop, range: RangeExpr) {
+        val target = AsmAssignTarget(TargetStorageKind.VARIABLE, program, asmgen, stmt.loopVarDt(program).typeOrElse(DataType.STRUCT), variable=stmt.loopVar)
+        val src = AsmAssignSource.fromAstSource(range.from, program).adjustDataTypeToTarget(target)
+        val assign = AsmAssignment(src, target, false, range.position)
+        asmgen.translateNormalAssignment(assign)
+    }
 }

compiler/src/prog8/compiler/target/c64/codegen/FunctionCallAsmGen.kt

@@ -4,13 +4,11 @@ import prog8.ast.IFunctionCall
 import prog8.ast.Program
 import prog8.ast.base.*
 import prog8.ast.expressions.*
-import prog8.ast.statements.AssignTarget
+import prog8.ast.statements.RegisterOrStatusflag
 import prog8.ast.statements.Subroutine
 import prog8.ast.statements.SubroutineParameter
 import prog8.compiler.AssemblyError
-import prog8.compiler.target.c64.C64MachineDefinition.ESTACK_HI_HEX
-import prog8.compiler.target.c64.C64MachineDefinition.ESTACK_LO_HEX
-import prog8.compiler.toHex
+import prog8.compiler.target.c64.codegen.assignment.*
 
 
 internal class FunctionCallAsmGen(private val program: Program, private val asmgen: AsmGen) {
@@ -19,11 +17,11 @@ internal class FunctionCallAsmGen(private val program: Program, private val asmg
         // output the code to setup the parameters and perform the actual call
         // does NOT output the code to deal with the result values!
         val sub = stmt.target.targetSubroutine(program.namespace) ?: throw AssemblyError("undefined subroutine ${stmt.target}")
-        val saveX = CpuRegister.X in sub.asmClobbers || sub.regXasResult()
+        val saveX = CpuRegister.X in sub.asmClobbers || sub.regXasResult() || sub.regXasParam()
         if(saveX)
-            asmgen.out("  stx  c64.SCRATCH_ZPREGX")        // we only save X for now (required! is the eval stack pointer), screw A and Y...
+            asmgen.saveRegister(CpuRegister.X)
 
-        val subName = asmgen.asmIdentifierName(stmt.target)
+        val subName = asmgen.asmSymbolName(stmt.target)
         if(stmt.args.isNotEmpty()) {
             if(sub.asmParameterRegisters.isEmpty()) {
                 // via variables
@@ -51,7 +49,7 @@ internal class FunctionCallAsmGen(private val program: Program, private val asmg
                         }
                         else -> {
                             // Risk of clobbering due to complex expression args. Work via the stack.
-                            argsViaStackEvaluation(stmt, sub)
+                            registerArgsViaStackEvaluation(stmt, sub)
                         }
                     }
                 }
@@ -60,39 +58,85 @@ internal class FunctionCallAsmGen(private val program: Program, private val asmg
         asmgen.out("  jsr  $subName")
 
         if(saveX)
-            asmgen.out("  ldx  c64.SCRATCH_ZPREGX")        // restore X again
+            asmgen.restoreRegister(CpuRegister.X)
     }
 
-    private fun argsViaStackEvaluation(stmt: IFunctionCall, sub: Subroutine) {
+    private fun registerArgsViaStackEvaluation(stmt: IFunctionCall, sub: Subroutine) {
+        // this is called when one or more of the arguments are 'complex' and
+        // cannot be assigned to a register easily or risk clobbering other registers.
+
+        if(sub.parameters.isEmpty())
+            return
+
+        // 1. load all arguments reversed onto the stack: first arg goes last (is on top).
         for (arg in stmt.args.reversed())
             asmgen.translateExpression(arg)
-        for (regparam in sub.asmParameterRegisters) {
-            when (regparam.registerOrPair) {
-                RegisterOrPair.A -> asmgen.out(" inx |  lda  $ESTACK_LO_HEX,x")
-                RegisterOrPair.X -> throw AssemblyError("can't pop into X register - use a variable instead")
-                RegisterOrPair.Y -> asmgen.out(" inx |  ldy  $ESTACK_LO_HEX,x")
-                RegisterOrPair.AX -> throw AssemblyError("can't pop into X register - use a variable instead")
-                RegisterOrPair.AY -> asmgen.out(" inx |  lda  $ESTACK_LO_HEX,x |  ldy  $ESTACK_HI_HEX,x")
-                RegisterOrPair.XY -> throw AssemblyError("can't pop into X register - use a variable instead")
-                null -> {
+
+        var argForCarry: IndexedValue<Pair<Expression, RegisterOrStatusflag>>? = null
+        var argForXregister: IndexedValue<Pair<Expression, RegisterOrStatusflag>>? = null
+        var argForAregister: IndexedValue<Pair<Expression, RegisterOrStatusflag>>? = null
+
+        asmgen.out("  inx")     // align estack pointer
+
+        for(argi in stmt.args.zip(sub.asmParameterRegisters).withIndex()) {
+            when {
+                argi.value.second.stack -> TODO("asmsub @stack parameter")
+                argi.value.second.statusflag == Statusflag.Pc -> {
+                    require(argForCarry == null)
+                    argForCarry = argi
                 }
-            }
-            when (regparam.statusflag) {
-                Statusflag.Pc -> asmgen.out("""
-                        inx
-                        pha
-                        lda  $ESTACK_LO_HEX,x
-                        beq  +
-                        sec  
-                        bcs  ++
-            +           clc
-            +           pla
-            """)
-                null -> {
+                argi.value.second.statusflag != null -> throw AssemblyError("can only use Carry as status flag parameter")
+                argi.value.second.registerOrPair in setOf(RegisterOrPair.X, RegisterOrPair.AX, RegisterOrPair.XY) -> {
+                    require(argForXregister==null)
+                    argForXregister = argi
                 }
-                else -> throw AssemblyError("can only use Carry as status flag parameter")
+                argi.value.second.registerOrPair in setOf(RegisterOrPair.A, RegisterOrPair.AY) -> {
+                    require(argForAregister == null)
+                    argForAregister = argi
+                }
+                argi.value.second.registerOrPair == RegisterOrPair.Y -> {
+                    asmgen.out("  ldy  P8ESTACK_LO+${argi.index},x")
+                }
+                else -> throw AssemblyError("weird argument")
             }
         }
+
+        if(argForCarry!=null) {
+            asmgen.out("""
+                lda  P8ESTACK_LO+${argForCarry.index},x
+                beq  +
+                sec
+                bcs  ++
++               clc
++               php""")             // push the status flags
+        }
+
+        if(argForAregister!=null) {
+            when(argForAregister.value.second.registerOrPair) {
+                RegisterOrPair.A -> asmgen.out("  lda  P8ESTACK_LO+${argForAregister.index},x")
+                RegisterOrPair.AY -> asmgen.out("  lda  P8ESTACK_LO+${argForAregister.index},x |  ldy  P8ESTACK_HI+${argForAregister.index},x")
+                else -> throw AssemblyError("weird arg")
+            }
+        }
+
+        if(argForXregister!=null) {
+
+            if(argForAregister!=null)
+                asmgen.out("  pha")
+            when(argForXregister.value.second.registerOrPair) {
+                RegisterOrPair.X -> asmgen.out("  lda  P8ESTACK_LO+${argForXregister.index},x |  tax")
+                RegisterOrPair.AX -> asmgen.out("  ldy  P8ESTACK_LO+${argForXregister.index},x |  lda  P8ESTACK_HI+${argForXregister.index},x |  tax |  tya")
+                RegisterOrPair.XY -> asmgen.out("  ldy  P8ESTACK_HI+${argForXregister.index},x |  lda  P8ESTACK_LO+${argForXregister.index},x |  tax")
+                else -> throw AssemblyError("weird arg")
+            }
+            if(argForAregister!=null)
+                asmgen.out("  pla")
+        } else {
+            repeat(sub.parameters.size - 1) { asmgen.out("  inx") }       // unwind stack
+        }
+
+        if(argForCarry!=null)
+            asmgen.out("  plp")       // set the carry flag back to correct value
     }
 
     private fun argumentViaVariable(sub: Subroutine, parameter: IndexedValue<SubroutineParameter>, value: Expression) {
@@ -101,55 +145,16 @@ internal class FunctionCallAsmGen(private val program: Program, private val asmg
         if(!valueIDt.isKnown)
             throw AssemblyError("arg type unknown")
         val valueDt = valueIDt.typeOrElse(DataType.STRUCT)
-        if(!argumentTypeCompatible(valueDt, parameter.value.type))
+        if(!isArgumentTypeCompatible(valueDt, parameter.value.type))
             throw AssemblyError("argument type incompatible")
 
-        val paramVar = parameter.value
-        val scopedParamVar = (sub.scopedname+"."+paramVar.name).split(".")
-        val target = AssignTarget(IdentifierReference(scopedParamVar, sub.position), null, null, sub.position)
-        target.linkParents(value.parent)
-        when (value) {
-            is NumericLiteralValue -> {
-                // optimize when the argument is a constant literal
-                when(parameter.value.type) {
-                    in ByteDatatypes -> asmgen.assignFromByteConstant(target, value.number.toShort())
-                    in WordDatatypes -> asmgen.assignFromWordConstant(target, value.number.toInt())
-                    DataType.FLOAT -> asmgen.assignFromFloatConstant(target, value.number.toDouble())
-                    in PassByReferenceDatatypes -> throw AssemblyError("can't pass string/array as argument via a variable?")    // TODO huh
-                    else -> throw AssemblyError("weird parameter datatype")
-                }
-            }
-            is IdentifierReference -> {
-                // optimize when the argument is a variable
-                when (parameter.value.type) {
-                    in ByteDatatypes -> asmgen.assignFromByteVariable(target, value)
-                    in WordDatatypes -> asmgen.assignFromWordVariable(target, value)
-                    DataType.FLOAT -> asmgen.assignFromFloatVariable(target, value)
-                    in PassByReferenceDatatypes -> throw AssemblyError("can't pass string/array as argument via a variable?")     // TODO huh
-                    else -> throw AssemblyError("weird parameter datatype")
-                }
-            }
-            is DirectMemoryRead -> {
-                when(value.addressExpression) {
-                    is NumericLiteralValue -> {
-                        val address = (value.addressExpression as NumericLiteralValue).number.toInt()
-                        asmgen.assignFromMemoryByte(target, address, null)
-                    }
-                    is IdentifierReference -> {
-                        asmgen.assignFromMemoryByte(target, null, value.addressExpression as IdentifierReference)
-                    }
-                    else -> {
-                        asmgen.translateExpression(value.addressExpression)
-                        asmgen.out("  jsr  prog8_lib.read_byte_from_address |  inx")
-                        asmgen.assignFromRegister(target, CpuRegister.A)
-                    }
-                }
-            }
-            else -> {
-                asmgen.translateExpression(value)
-                asmgen.assignFromEvalResult(target)
-            }
-        }
+        val scopedParamVar = (sub.scopedname+"."+parameter.value.name).split(".")
+        val identifier = IdentifierReference(scopedParamVar, sub.position)
+        identifier.linkParents(value.parent)
+        val tgt = AsmAssignTarget(TargetStorageKind.VARIABLE, program, asmgen, parameter.value.type, variable = identifier)
+        val source = AsmAssignSource.fromAstSource(value, program).adjustDataTypeToTarget(tgt)
+        val asgn = AsmAssignment(source, tgt, false, Position.DUMMY)
+        asmgen.translateNormalAssignment(asgn)
     }
 
     private fun argumentViaRegister(sub: Subroutine, parameter: IndexedValue<SubroutineParameter>, value: Expression) {
@@ -158,7 +163,7 @@ internal class FunctionCallAsmGen(private val program: Program, private val asmg
         if(!valueIDt.isKnown)
             throw AssemblyError("arg type unknown")
         val valueDt = valueIDt.typeOrElse(DataType.STRUCT)
-        if(!argumentTypeCompatible(valueDt, parameter.value.type))
+        if(!isArgumentTypeCompatible(valueDt, parameter.value.type))
             throw AssemblyError("argument type incompatible")
 
         val paramRegister = sub.asmParameterRegisters[parameter.index]
@@ -181,14 +186,15 @@ internal class FunctionCallAsmGen(private val program: Program, private val asmg
                             asmgen.out(if(carrySet) "  sec" else "  clc")
                         }
                         is IdentifierReference -> {
-                            val sourceName = asmgen.asmIdentifierName(value)
+                            val sourceName = asmgen.asmVariableName(value)
                             asmgen.out("""
+            pha
             lda  $sourceName
             beq  +
             sec  
             bcs  ++
 +           clc
-+
++           pla
 """)
                         }
                         else -> {
@@ -196,7 +202,7 @@ internal class FunctionCallAsmGen(private val program: Program, private val asmg
                             asmgen.out("""
             inx
             pha
-            lda  $ESTACK_LO_HEX,x
+            lda  P8ESTACK_LO,x
             beq  +
             sec  
             bcs  ++
@@ -208,79 +214,22 @@ internal class FunctionCallAsmGen(private val program: Program, private val asmg
                 }
                 else throw AssemblyError("can only use Carry as status flag parameter")
             }
-            register!=null && register.name.length==1 -> {
-                when (value) {
-                    is NumericLiteralValue -> {
-                        asmgen.assignToRegister(CpuRegister.valueOf(register.name), value.number.toShort(), null)
-                    }
-                    is IdentifierReference -> {
-                        asmgen.assignToRegister(CpuRegister.valueOf(register.name), null, value)
-                    }
-                    else -> {
-                        asmgen.translateExpression(value)
-                        when(register) {
-                            RegisterOrPair.A -> asmgen.out("  inx | lda  $ESTACK_LO_HEX,x")
-                            RegisterOrPair.X -> throw AssemblyError("can't pop into X register - use a variable instead")
-                            RegisterOrPair.Y -> asmgen.out("  inx | ldy  $ESTACK_LO_HEX,x")
-                            else -> throw AssemblyError("cannot assign to register pair")
-                        }
-                    }
-                }
-            }
-            register!=null && register.name.length==2 -> {
-                // register pair as a 16-bit value (only possible for subroutine parameters)
-                when (value) {
-                    is NumericLiteralValue -> {
-                        // optimize when the argument is a constant literal
-                        val hex = value.number.toHex()
-                        when (register) {
-                            RegisterOrPair.AX -> asmgen.out("  lda  #<$hex  |  ldx  #>$hex")
-                            RegisterOrPair.AY -> asmgen.out("  lda  #<$hex  |  ldy  #>$hex")
-                            RegisterOrPair.XY -> asmgen.out("  ldx  #<$hex  |  ldy  #>$hex")
-                            else -> {}
-                        }
-                    }
-                    is AddressOf -> {
-                        // optimize when the argument is an address of something
-                        val sourceName = asmgen.asmIdentifierName(value.identifier)
-                        when (register) {
-                            RegisterOrPair.AX -> asmgen.out("  lda  #<$sourceName  |  ldx  #>$sourceName")
-                            RegisterOrPair.AY -> asmgen.out("  lda  #<$sourceName  |  ldy  #>$sourceName")
-                            RegisterOrPair.XY -> asmgen.out("  ldx  #<$sourceName  |  ldy  #>$sourceName")
-                            else -> {}
-                        }
-                    }
-                    is IdentifierReference -> {
-                        val sourceName = asmgen.asmIdentifierName(value)
-                        if(valueDt in PassByReferenceDatatypes) {
-                            when (register) {
-                                RegisterOrPair.AX -> asmgen.out("  lda  #<$sourceName  |  ldx  #>$sourceName")
-                                RegisterOrPair.AY -> asmgen.out("  lda  #<$sourceName  |  ldy  #>$sourceName")
-                                RegisterOrPair.XY -> asmgen.out("  ldx  #<$sourceName  |  ldy  #>$sourceName")
-                                else -> {}
-                            }
-                        } else {
-                            when (register) {
-                                RegisterOrPair.AX -> asmgen.out("  lda  $sourceName  |  ldx  $sourceName+1")
-                                RegisterOrPair.AY -> asmgen.out("  lda  $sourceName  |  ldy  $sourceName+1")
-                                RegisterOrPair.XY -> asmgen.out("  ldx  $sourceName  |  ldy  $sourceName+1")
-                                else -> {}
-                            }
-                        }
-                    }
-                    else -> {
-                        asmgen.translateExpression(value)
-                        if (register == RegisterOrPair.AX || register == RegisterOrPair.XY)
-                            throw AssemblyError("can't use X register here - use a variable")
-                        else if (register == RegisterOrPair.AY)
-                            asmgen.out("  inx |  lda  $ESTACK_LO_HEX,x  |  ldy  $ESTACK_HI_HEX,x")
-                    }
+            else -> {
+                // via register or register pair
+                val target = AsmAssignTarget.fromRegisters(register!!, program, asmgen)
+                val src = if(valueDt in PassByReferenceDatatypes) {
+                    val addr = AddressOf(value as IdentifierReference, Position.DUMMY)
+                    AsmAssignSource.fromAstSource(addr, program).adjustDataTypeToTarget(target)
+                } else {
+                    AsmAssignSource.fromAstSource(value, program).adjustDataTypeToTarget(target)
                 }
+
+                asmgen.translateNormalAssignment(AsmAssignment(src, target, false, Position.DUMMY))
             }
         }
     }
 
-    private fun argumentTypeCompatible(argType: DataType, paramType: DataType): Boolean {
+    private fun isArgumentTypeCompatible(argType: DataType, paramType: DataType): Boolean {
         if(argType isAssignableTo paramType)
             return true
         if(argType in ByteDatatypes && paramType in ByteDatatypes)

compiler/src/prog8/compiler/target/c64/codegen/PostIncrDecrAsmGen.kt

@@ -6,7 +6,6 @@ import prog8.ast.expressions.IdentifierReference
 import prog8.ast.expressions.NumericLiteralValue
 import prog8.ast.statements.PostIncrDecr
 import prog8.compiler.AssemblyError
-import prog8.compiler.target.c64.C64MachineDefinition.C64Zeropage
 import prog8.compiler.toHex
 
 
@@ -18,7 +17,7 @@ internal class PostIncrDecrAsmGen(private val program: Program, private val asmg
         val targetArrayIdx = stmt.target.arrayindexed
         when {
             targetIdent!=null -> {
-                val what = asmgen.asmIdentifierName(targetIdent)
+                val what = asmgen.asmVariableName(targetIdent)
                 when (stmt.target.inferType(program, stmt).typeOrElse(DataType.STRUCT)) {
                     in ByteDatatypes -> asmgen.out(if (incr) "  inc  $what" else "  dec  $what")
                     in WordDatatypes -> {
@@ -46,83 +45,91 @@ internal class PostIncrDecrAsmGen(private val program: Program, private val asmg
                         asmgen.out(if(incr) "  inc  $what" else "  dec  $what")
                     }
                     is IdentifierReference -> {
-                        val what = asmgen.asmIdentifierName(addressExpr)
+                        val what = asmgen.asmVariableName(addressExpr)
                         asmgen.out("  lda  $what |  sta  (+) +1 |  lda  $what+1 |  sta  (+) +2")
                         if(incr)
                             asmgen.out("+\tinc  ${'$'}ffff\t; modified")
                         else
                             asmgen.out("+\tdec  ${'$'}ffff\t; modified")
                     }
-                    else -> throw AssemblyError("weird target type $targetMemory")
+                    else -> {
+                        asmgen.translateExpression(addressExpr)
+                        asmgen.out("""
+                            inx
+                            lda  P8ESTACK_LO,x
+                            sta  (+) + 1
+                            lda  P8ESTACK_HI,x
+                            sta  (+) + 2
+                        """)
+                        if(incr)
+                            asmgen.out("+\tinc  ${'$'}ffff\t; modified")
+                        else
+                            asmgen.out("+\tdec  ${'$'}ffff\t; modified")
+                    }
                 }
             }
             targetArrayIdx!=null -> {
                 val index = targetArrayIdx.arrayspec.index
-                val what = asmgen.asmIdentifierName(targetArrayIdx.identifier)
-                val arrayDt = targetArrayIdx.identifier.inferType(program).typeOrElse(DataType.STRUCT)
-                val elementDt = ArrayElementTypes.getValue(arrayDt)
+                val asmArrayvarname = asmgen.asmVariableName(targetArrayIdx.identifier)
+                val elementDt = targetArrayIdx.inferType(program).typeOrElse(DataType.STRUCT)
                 when(index) {
                     is NumericLiteralValue -> {
                         val indexValue = index.number.toInt() * elementDt.memorySize()
                         when(elementDt) {
-                            in ByteDatatypes -> asmgen.out(if (incr) "  inc  $what+$indexValue" else "  dec  $what+$indexValue")
+                            in ByteDatatypes -> asmgen.out(if (incr) "  inc  $asmArrayvarname+$indexValue" else "  dec  $asmArrayvarname+$indexValue")
                             in WordDatatypes -> {
                                 if(incr)
-                                    asmgen.out(" inc  $what+$indexValue |  bne  + |  inc  $what+$indexValue+1 |+")
+                                    asmgen.out(" inc  $asmArrayvarname+$indexValue |  bne  + |  inc  $asmArrayvarname+$indexValue+1 |+")
                                 else
                                     asmgen.out("""
-        lda  $what+$indexValue
+        lda  $asmArrayvarname+$indexValue
         bne  +
-        dec  $what+$indexValue+1
-+       dec  $what+$indexValue 
+        dec  $asmArrayvarname+$indexValue+1
++       dec  $asmArrayvarname+$indexValue 
 """)
                             }
                             DataType.FLOAT -> {
-                                asmgen.out("  lda  #<$what+$indexValue |  ldy  #>$what+$indexValue")
+                                asmgen.out("  lda  #<$asmArrayvarname+$indexValue |  ldy  #>$asmArrayvarname+$indexValue")
                                 asmgen.out(if(incr) "  jsr  c64flt.inc_var_f" else "  jsr  c64flt.dec_var_f")
                             }
                             else -> throw AssemblyError("need numeric type")
                         }
                     }
-                    is IdentifierReference -> {
-                        asmgen.translateArrayIndexIntoA(targetArrayIdx)
-                        incrDecrArrayvalueWithIndexA(incr, arrayDt, what)
-                    }
                     else -> {
-                        asmgen.translateArrayIndexIntoA(targetArrayIdx)
-                        incrDecrArrayvalueWithIndexA(incr, arrayDt, what)
+                        asmgen.loadScaledArrayIndexIntoRegister(targetArrayIdx, elementDt, CpuRegister.A)
+                        asmgen.saveRegister(CpuRegister.X)
+                        asmgen.out("  tax")
+                        when(elementDt) {
+                            in ByteDatatypes -> {
+                                asmgen.out(if(incr) "  inc  $asmArrayvarname,x" else "  dec  $asmArrayvarname,x")
+                            }
+                            in WordDatatypes -> {
+                                if(incr)
+                                    asmgen.out(" inc  $asmArrayvarname,x |  bne  + |  inc  $asmArrayvarname+1,x |+")
+                                else
+                                    asmgen.out("""
+        lda  $asmArrayvarname,x
+        bne  +
+        dec  $asmArrayvarname+1,x
++       dec  $asmArrayvarname 
+""")
+                            }
+                            DataType.FLOAT -> {
+                                asmgen.out("""
+                        ldy  #>$asmArrayvarname
+                        clc
+                        adc  #<$asmArrayvarname
+                        bcc  +
+                        iny
++                       jsr  c64flt.inc_var_f""")
+                            }
+                            else -> throw AssemblyError("weird array elt dt")
+                        }
+                        asmgen.restoreRegister(CpuRegister.X)
                     }
                 }
             }
             else -> throw AssemblyError("weird target type ${stmt.target}")
         }
     }
-
-    private fun incrDecrArrayvalueWithIndexA(incr: Boolean, arrayDt: DataType, arrayVarName: String) {
-        asmgen.out("  stx  ${C64Zeropage.SCRATCH_REG_X} |  tax")
-        when(arrayDt) {
-            DataType.STR,
-            DataType.ARRAY_UB, DataType.ARRAY_B -> {
-                asmgen.out(if(incr) "  inc  $arrayVarName,x" else "  dec  $arrayVarName,x")
-            }
-            DataType.ARRAY_UW, DataType.ARRAY_W -> {
-                if(incr)
-                    asmgen.out(" inc  $arrayVarName,x |  bne  + |  inc  $arrayVarName+1,x |+")
-                else
-                    asmgen.out("""
-        lda  $arrayVarName,x
-        bne  +
-        dec  $arrayVarName+1,x
-+       dec  $arrayVarName 
-""")
-            }
-            DataType.ARRAY_F -> {
-                asmgen.out("  lda  #<$arrayVarName |  ldy  #>$arrayVarName")
-                asmgen.out(if(incr) "  jsr  c64flt.inc_indexed_var_f" else "  jsr  c64flt.dec_indexed_var_f")
-            }
-            else -> throw AssemblyError("weird array dt")
-        }
-        asmgen.out("  ldx  ${C64Zeropage.SCRATCH_REG_X}")
-    }
-
 }

compiler/src/prog8/compiler/target/c64/codegen/assignment/AsmAssignment.kt

@@ -0,0 +1,165 @@
+package prog8.compiler.target.c64.codegen.assignment
+
+import prog8.ast.Program
+import prog8.ast.base.*
+import prog8.ast.expressions.*
+import prog8.ast.statements.AssignTarget
+import prog8.ast.statements.Assignment
+import prog8.ast.statements.DirectMemoryWrite
+import prog8.compiler.AssemblyError
+import prog8.compiler.target.c64.codegen.AsmGen
+
+
+internal enum class TargetStorageKind {
+    VARIABLE,
+    ARRAY,
+    MEMORY,
+    REGISTER,
+    STACK
+}
+
+internal enum class SourceStorageKind {
+    LITERALNUMBER,
+    VARIABLE,
+    ARRAY,
+    MEMORY,
+    REGISTER,
+    STACK,              // value is already present on stack
+    EXPRESSION,         // expression in ast-form, still to be evaluated
+}
+
+internal class AsmAssignTarget(val kind: TargetStorageKind,
+                               program: Program,
+                               asmgen: AsmGen,
+                               val datatype: DataType,
+                               val variable: IdentifierReference? = null,
+                               val array: ArrayIndexedExpression? = null,
+                               val memory: DirectMemoryWrite? = null,
+                               val register: RegisterOrPair? = null,
+                               val origAstTarget: AssignTarget? = null
+                               )
+{
+    val constMemoryAddress by lazy { memory?.addressExpression?.constValue(program)?.number?.toInt() ?: 0}
+    val constArrayIndexValue by lazy { array?.arrayspec?.constIndex() }
+    val vardecl by lazy { variable?.targetVarDecl(program.namespace)!! }
+    val asmVarname by lazy {
+        if(variable!=null)
+            asmgen.asmVariableName(variable)
+        else
+            asmgen.asmVariableName(array!!.identifier)
+    }
+
+    lateinit var origAssign: AsmAssignment
+
+    init {
+        if(variable!=null && vardecl.type == VarDeclType.CONST)
+            throw AssemblyError("can't assign to a constant")
+        if(register!=null && datatype !in IntegerDatatypes)
+            throw AssemblyError("register must be integer type")
+    }
+
+    companion object {
+        fun fromAstAssignment(assign: Assignment, program: Program, asmgen: AsmGen): AsmAssignTarget = with(assign.target) {
+            val dt = inferType(program, assign).typeOrElse(DataType.STRUCT)
+            when {
+                identifier != null -> AsmAssignTarget(TargetStorageKind.VARIABLE, program, asmgen, dt, variable=identifier, origAstTarget =  this)
+                arrayindexed != null -> AsmAssignTarget(TargetStorageKind.ARRAY, program, asmgen, dt, array = arrayindexed, origAstTarget =  this)
+                memoryAddress != null -> AsmAssignTarget(TargetStorageKind.MEMORY, program, asmgen, dt, memory =  memoryAddress, origAstTarget =  this)
+                else -> throw AssemblyError("weird target")
+            }
+        }
+
+        fun fromRegisters(registers: RegisterOrPair, program: Program, asmgen: AsmGen): AsmAssignTarget =
+                when(registers) {
+                    RegisterOrPair.A,
+                    RegisterOrPair.X,
+                    RegisterOrPair.Y -> AsmAssignTarget(TargetStorageKind.REGISTER, program, asmgen, DataType.UBYTE, register = registers)
+                    RegisterOrPair.AX,
+                    RegisterOrPair.AY,
+                    RegisterOrPair.XY -> AsmAssignTarget(TargetStorageKind.REGISTER, program, asmgen, DataType.UWORD, register = registers)
+                }
+    }
+}
+
+internal class AsmAssignSource(val kind: SourceStorageKind,
+                               private val program: Program,
+                               val datatype: DataType,
+                               val variable: IdentifierReference? = null,
+                               val array: ArrayIndexedExpression? = null,
+                               val memory: DirectMemoryRead? = null,
+                               val register: CpuRegister? = null,
+                               val number: NumericLiteralValue? = null,
+                               val expression: Expression? = null
+)
+{
+    val constMemoryAddress by lazy { memory?.addressExpression?.constValue(program)?.number?.toInt() ?: 0}
+    val constArrayIndexValue by lazy { array?.arrayspec?.constIndex() }
+    val vardecl by lazy { variable?.targetVarDecl(program.namespace)!! }
+
+    companion object {
+        fun fromAstSource(value: Expression, program: Program): AsmAssignSource {
+            val cv = value.constValue(program)
+            if(cv!=null)
+                return AsmAssignSource(SourceStorageKind.LITERALNUMBER, program, cv.type, number = cv)
+
+            return when(value) {
+                is NumericLiteralValue -> AsmAssignSource(SourceStorageKind.LITERALNUMBER, program, value.type, number = cv)
+                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)
+                    AsmAssignSource(SourceStorageKind.VARIABLE, program, dt, variable = value)
+                }
+                is DirectMemoryRead -> {
+                    AsmAssignSource(SourceStorageKind.MEMORY, program, DataType.UBYTE, memory = value)
+                }
+                is ArrayIndexedExpression -> {
+                    val dt = value.inferType(program).typeOrElse(DataType.STRUCT)
+                    AsmAssignSource(SourceStorageKind.ARRAY, program, dt, array = value)
+                }
+                else -> {
+                    val dt = value.inferType(program).typeOrElse(DataType.STRUCT)
+                    AsmAssignSource(SourceStorageKind.EXPRESSION, program, dt, expression = value)
+                }
+            }
+        }
+    }
+
+    fun getAstValue(): Expression = when(kind) {
+        SourceStorageKind.LITERALNUMBER -> number!!
+        SourceStorageKind.VARIABLE -> variable!!
+        SourceStorageKind.ARRAY -> array!!
+        SourceStorageKind.MEMORY -> memory!!
+        SourceStorageKind.EXPRESSION -> expression!!
+        SourceStorageKind.REGISTER -> throw AssemblyError("cannot get a register source as Ast node")
+        SourceStorageKind.STACK -> throw AssemblyError("cannot get a stack source as Ast node")
+    }
+
+    fun withAdjustedDt(newType: DataType) =
+            AsmAssignSource(kind, program, newType, variable, array, memory, register, number, expression)
+
+    fun adjustDataTypeToTarget(target: AsmAssignTarget): AsmAssignSource {
+        // allow some signed/unsigned relaxations
+        if(target.datatype!=datatype) {
+            if(target.datatype in ByteDatatypes && datatype in ByteDatatypes) {
+                return withAdjustedDt(target.datatype)
+            } else if(target.datatype in WordDatatypes && datatype in WordDatatypes) {
+                return withAdjustedDt(target.datatype)
+            }
+        }
+        return this
+    }
+
+}
+
+
+internal class AsmAssignment(val source: AsmAssignSource,
+                             val target: AsmAssignTarget,
+                             val isAugmentable: Boolean,
+                             val position: Position) {
+
+    init {
+        if(target.register !in setOf(RegisterOrPair.XY, RegisterOrPair.AX, RegisterOrPair.AY))
+            require(source.datatype.memorySize() == target.datatype.memorySize()) { "source and target datatype must be same storage class" }
+    }
+}

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

@@ -0,0 +1,123 @@
+package prog8.compiler.target.cx16
+
+import prog8.ast.Program
+import prog8.compiler.*
+import prog8.compiler.target.CpuType
+import prog8.compiler.target.IMachineDefinition
+import prog8.compiler.target.c64.C64MachineDefinition
+import prog8.parser.ModuleImporter
+import java.io.IOException
+
+internal object CX16MachineDefinition: IMachineDefinition {
+
+    override val cpu = CpuType.CPU65c02
+
+    // 5-byte cbm MFLPT format limitations:
+    override val FLOAT_MAX_POSITIVE = 1.7014118345e+38         // bytes: 255,127,255,255,255
+    override val FLOAT_MAX_NEGATIVE = -1.7014118345e+38        // bytes: 255,255,255,255,255
+    override val FLOAT_MEM_SIZE = 5
+    override val POINTER_MEM_SIZE = 2
+    override val BASIC_LOAD_ADDRESS = 0x0801
+    override val RAW_LOAD_ADDRESS = 0x8000
+
+    // the 2*256 byte evaluation stack (on which bytes, words, and even floats are stored during calculations)
+    // and some heavily used string constants derived from the two values above
+    override val ESTACK_LO = 0x0400        //  $0400-$04ff inclusive
+    override val ESTACK_HI = 0x0500        //  $0500-$05ff inclusive
+
+    override lateinit var zeropage: Zeropage
+
+    override fun getFloat(num: Number) = C64MachineDefinition.Mflpt5.fromNumber(num)
+
+    override fun getFloatRomConst(number: Double): String? = null       // Cx16 has no pulblic ROM float locations
+    override fun importLibs(compilerOptions: CompilationOptions, importer: ModuleImporter, program: Program) {
+        if (compilerOptions.launcher == LauncherType.BASIC || compilerOptions.output == OutputType.PRG)
+            importer.importLibraryModule(program, "cx16lib")
+    }
+
+    override fun launchEmulator(programName: String) {
+        for(emulator in listOf("x16emu")) {
+            println("\nStarting Commander X16 emulator $emulator...")
+            val cmdline = listOf(emulator, "-rom", "/usr/share/x16-rom/rom.bin", "-scale", "2",
+                    "-run", "-prg", programName + ".prg")
+            val processb = ProcessBuilder(cmdline).inheritIO()
+            val process: Process
+            try {
+                process=processb.start()
+            } catch(x: IOException) {
+                continue  // try the next emulator executable
+            }
+            process.waitFor()
+            break
+        }
+    }
+
+    override fun initializeZeropage(compilerOptions: CompilationOptions) {
+        zeropage = CX16Zeropage(compilerOptions)
+    }
+
+    // 6502 opcodes (including aliases and illegal opcodes), these cannot be used as variable or label names
+    override val opcodeNames = setOf("adc", "and", "asl", "bcc", "bcs",
+            "beq", "bge", "bit", "blt", "bmi", "bne", "bpl", "brk", "bvc", "bvs", "clc",
+            "cld", "cli", "clv", "cmp", "cpx", "cpy", "dec", "dex", "dey",
+            "eor", "gcc", "gcs", "geq", "gge", "glt", "gmi", "gne", "gpl", "gvc", "gvs",
+            "inc", "inx", "iny", "jmp", "jsr",
+            "lda", "ldx", "ldy", "lsr", "nop", "ora", "pha", "php",
+            "pla", "plp", "rol", "ror", "rti", "rts", "sbc",
+            "sec", "sed", "sei",
+            "sta", "stx", "sty", "tax", "tay", "tsx", "txa", "txs", "tya",
+            "bra", "phx", "phy", "plx", "ply", "stz", "trb", "tsb", "bbr", "bbs",
+            "rmb", "smb", "stp", "wai")
+
+
+    internal class CX16Zeropage(options: CompilationOptions) : Zeropage(options) {
+
+        override val SCRATCH_B1 = 0x79      // temp storage for a single byte
+        override val SCRATCH_REG = 0x7a     // temp storage for a register
+        override val SCRATCH_W1 = 0x7c      // temp storage 1 for a word  $7c+$7d
+        override val SCRATCH_W2 = 0x7e      // temp storage 2 for a word  $7e+$7f
+
+
+        override val exitProgramStrategy: ExitProgramStrategy = when (options.zeropage) {
+            ZeropageType.BASICSAFE, ZeropageType.DONTUSE -> ExitProgramStrategy.CLEAN_EXIT
+            ZeropageType.KERNALSAFE, ZeropageType.FULL -> ExitProgramStrategy.SYSTEM_RESET
+            else -> ExitProgramStrategy.SYSTEM_RESET
+        }
+
+
+        init {
+            if (options.floats && options.zeropage !in setOf(ZeropageType.BASICSAFE, ZeropageType.DONTUSE ))
+                throw CompilerException("when floats are enabled, zero page type should be 'basicsafe' or 'dontuse'")
+
+            // the addresses 0x02 to 0x21 (inclusive) are taken for sixteen virtual 16-bit api registers.
+
+            when (options.zeropage) {
+                ZeropageType.FULL -> {
+                    free.addAll(0x22..0xff)
+                    free.removeAll(listOf(SCRATCH_B1, SCRATCH_REG, SCRATCH_W1, SCRATCH_W1 + 1, SCRATCH_W2, SCRATCH_W2 + 1))
+                }
+                ZeropageType.KERNALSAFE -> {
+                    free.addAll(0x22..0x7f)
+                    free.addAll(0xa9..0xff)
+                    free.removeAll(listOf(SCRATCH_B1, SCRATCH_REG, SCRATCH_W1, SCRATCH_W1 + 1, SCRATCH_W2, SCRATCH_W2 + 1))
+                }
+                ZeropageType.BASICSAFE -> {
+                    free.addAll(0x22..0x7f)
+                    free.removeAll(listOf(SCRATCH_B1, SCRATCH_REG, SCRATCH_W1, SCRATCH_W1 + 1, SCRATCH_W2, SCRATCH_W2 + 1))
+                }
+                ZeropageType.DONTUSE -> {
+                    free.clear() // don't use zeropage at all
+                }
+                else -> throw CompilerException("for this machine target, zero page type 'floatsafe' is not available. ${options.zeropage}")
+            }
+
+            require(SCRATCH_B1 !in free)
+            require(SCRATCH_REG !in free)
+            require(SCRATCH_W1 !in free)
+            require(SCRATCH_W2 !in free)
+
+            for (reserved in options.zpReserved)
+                reserve(reserved)
+        }
+    }
+}

compiler/src/prog8/functions/BuiltinFunctions.kt

@@ -3,6 +3,8 @@ package prog8.functions
 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.*
 
@@ -25,8 +27,6 @@ val BuiltinFunctions = mapOf(
     "ror"         to FSignature(false, listOf(FParam("item", setOf(DataType.UBYTE, DataType.UWORD))), null),
     "rol2"        to FSignature(false, listOf(FParam("item", setOf(DataType.UBYTE, DataType.UWORD))), null),
     "ror2"        to FSignature(false, listOf(FParam("item", setOf(DataType.UBYTE, DataType.UWORD))), null),
-    "lsl"         to FSignature(false, listOf(FParam("item", IntegerDatatypes)), null),
-    "lsr"         to FSignature(false, listOf(FParam("item", IntegerDatatypes)), null),
     "sort"        to FSignature(false, listOf(FParam("array", ArrayDatatypes)), null),
     "reverse"     to FSignature(false, listOf(FParam("array", ArrayDatatypes)), null),
         // these few have a return value depending on the argument(s):
@@ -35,6 +35,7 @@ val BuiltinFunctions = mapOf(
     "sum"         to FSignature(true, listOf(FParam("values", ArrayDatatypes)), null) { a, p, prg -> collectionArg(a, p, prg, ::builtinSum) },      // type depends on args
     "abs"         to FSignature(true, listOf(FParam("value", NumericDatatypes)), null, ::builtinAbs),      // type depends on argument
     "len"         to FSignature(true, listOf(FParam("values", IterableDatatypes)), null, ::builtinLen),    // type is UBYTE or UWORD depending on actual length
+    "sizeof"      to FSignature(true, listOf(FParam("object", DataType.values().toSet())), DataType.UBYTE, ::builtinSizeof),
         // normal functions follow:
     "sgn"         to FSignature(true, listOf(FParam("value", NumericDatatypes)), DataType.BYTE, ::builtinSgn ),
     "sin"         to FSignature(true, listOf(FParam("rads", setOf(DataType.FLOAT))), DataType.FLOAT) { a, p, prg -> oneDoubleArg(a, p, prg, Math::sin) },
@@ -62,7 +63,7 @@ val BuiltinFunctions = mapOf(
     "all"         to FSignature(true, listOf(FParam("values", ArrayDatatypes)), DataType.UBYTE) { a, p, prg -> collectionArg(a, p, prg, ::builtinAll) },
     "lsb"         to FSignature(true, listOf(FParam("value", setOf(DataType.UWORD, DataType.WORD))), DataType.UBYTE) { a, p, prg -> oneIntArgOutputInt(a, p, prg) { x: Int -> x and 255 }},
     "msb"         to FSignature(true, listOf(FParam("value", setOf(DataType.UWORD, DataType.WORD))), DataType.UBYTE) { a, p, prg -> oneIntArgOutputInt(a, p, prg) { x: Int -> x ushr 8 and 255}},
-    "mkword"      to FSignature(true, listOf(FParam("lsb", setOf(DataType.UBYTE)), FParam("msb", setOf(DataType.UBYTE))), DataType.UWORD, ::builtinMkword),
+    "mkword"      to FSignature(true, listOf(FParam("msb", setOf(DataType.UBYTE)), FParam("lsb", setOf(DataType.UBYTE))), DataType.UWORD, ::builtinMkword),
     "rnd"         to FSignature(true, emptyList(), DataType.UBYTE),
     "rndw"        to FSignature(true, emptyList(), DataType.UWORD),
     "rndf"        to FSignature(true, emptyList(), DataType.FLOAT),
@@ -103,9 +104,9 @@ val BuiltinFunctions = mapOf(
             FParam("length", setOf(DataType.UBYTE))), null)
 )
 
-fun builtinMax(array: List<Number>): Number = array.maxBy { it.toDouble() }!!
+fun builtinMax(array: List<Number>): Number = array.maxByOrNull { it.toDouble() }!!
 
-fun builtinMin(array: List<Number>): Number = array.minBy { it.toDouble() }!!
+fun builtinMin(array: List<Number>): Number = array.minByOrNull { it.toDouble() }!!
 
 fun builtinSum(array: List<Number>): Number = array.sumByDouble { it.toDouble() }
 
@@ -240,59 +241,88 @@ private fun builtinAbs(args: List<Expression>, position: Position, program: Prog
     }
 }
 
+private fun builtinSizeof(args: List<Expression>, position: Position, program: Program): NumericLiteralValue {
+    // 1 arg, type = anything, result type = ubyte
+    if(args.size!=1)
+        throw SyntaxError("sizeof requires one argument", position)
+    if(args[0] !is IdentifierReference)
+        throw SyntaxError("sizeof argument should be an identifier", position)
+
+    val dt = args[0].inferType(program)
+    if(dt.isKnown) {
+        val target = (args[0] as IdentifierReference).targetStatement(program.namespace)
+                ?: throw CannotEvaluateException("sizeof", "no target")
+
+        fun structSize(target: StructDecl) =
+                NumericLiteralValue(DataType.UBYTE, target.statements.map { (it as VarDecl).datatype.memorySize() }.sum(), position)
+
+        return when {
+            dt.typeOrElse(DataType.STRUCT) in ArrayDatatypes -> {
+                val length = (target as VarDecl).arraysize!!.constIndex() ?: throw CannotEvaluateException("sizeof", "unknown array size")
+                val elementDt = ArrayElementTypes.getValue(dt.typeOrElse(DataType.STRUCT))
+                numericLiteral(elementDt.memorySize() * 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, dt.typeOrElse(DataType.STRUCT).memorySize(), position)
+        }
+    } else {
+        throw SyntaxError("sizeof invalid argument type", position)
+    }
+}
+
 private fun builtinStrlen(args: List<Expression>, position: Position, program: Program): NumericLiteralValue {
     if (args.size != 1)
         throw SyntaxError("strlen requires one argument", position)
-    val argument = args[0].constValue(program) ?: throw NotConstArgumentException()
-    if(argument.type != DataType.STR)
-        throw SyntaxError("strlen must have string argument", position)
-
-    throw NotConstArgumentException()       // this function is not considering the string argument a constant
+    val argument=args[0]
+    if(argument is StringLiteralValue)
+        return NumericLiteralValue.optimalInteger(argument.value.length, argument.position)
+    val vardecl = (argument as IdentifierReference).targetVarDecl(program.namespace)
+    if(vardecl!=null) {
+        if(vardecl.datatype!=DataType.STR)
+            throw SyntaxError("strlen must have string argument", position)
+        if(vardecl.autogeneratedDontRemove) {
+            return NumericLiteralValue.optimalInteger((vardecl.value as StringLiteralValue).value.length, argument.position)
+        }
+    }
+    throw NotConstArgumentException()
 }
 
 private fun builtinLen(args: List<Expression>, position: Position, program: Program): NumericLiteralValue {
     // note: in some cases the length is > 255 and then we have to return a UWORD type instead of a UBYTE.
     if(args.size!=1)
         throw SyntaxError("len requires one argument", position)
-    val constArg = args[0].constValue(program)
-    if(constArg!=null)
-        throw SyntaxError("len of weird argument ${args[0]}", position)
 
     val directMemVar = ((args[0] as? DirectMemoryRead)?.addressExpression as? IdentifierReference)?.targetVarDecl(program.namespace)
-    var arraySize = directMemVar?.arraysize?.size()
+    var arraySize = directMemVar?.arraysize?.constIndex()
     if(arraySize != null)
         return NumericLiteralValue.optimalInteger(arraySize, position)
     if(args[0] is ArrayLiteralValue)
         return NumericLiteralValue.optimalInteger((args[0] as ArrayLiteralValue).value.size, position)
     if(args[0] !is IdentifierReference)
-        throw SyntaxError("len argument should be an identifier, but is ${args[0]}", position)
+        throw SyntaxError("len argument should be an identifier", position)
     val target = (args[0] as IdentifierReference).targetVarDecl(program.namespace)
             ?: throw CannotEvaluateException("len", "no target vardecl")
 
     return when(target.datatype) {
-        DataType.ARRAY_UB, DataType.ARRAY_B, DataType.ARRAY_UW, DataType.ARRAY_W -> {
-            arraySize = target.arraysize?.size()
+        DataType.ARRAY_UB, DataType.ARRAY_B, DataType.ARRAY_UW, DataType.ARRAY_W, DataType.ARRAY_F -> {
+            arraySize = target.arraysize?.constIndex()
             if(arraySize==null)
                 throw CannotEvaluateException("len", "arraysize unknown")
-            if(arraySize>256)
-                throw CompilerException("array length exceeds byte limit ${target.position}")
-            NumericLiteralValue.optimalInteger(arraySize, args[0].position)
-        }
-        DataType.ARRAY_F -> {
-            arraySize = target.arraysize?.size()
-            if(arraySize==null)
-                throw CannotEvaluateException("len", "arraysize unknown")
-            if(arraySize>256)
-                throw CompilerException("array length exceeds byte limit ${target.position}")
             NumericLiteralValue.optimalInteger(arraySize, args[0].position)
         }
         DataType.STR -> {
             val refLv = target.value as StringLiteralValue
-            if(refLv.value.length>255)
-                throw CompilerException("string length exceeds byte limit ${refLv.position}")
             NumericLiteralValue.optimalInteger(refLv.value.length, args[0].position)
         }
-        in NumericDatatypes -> throw SyntaxError("len of weird argument ${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")
     }
 }
@@ -300,9 +330,9 @@ private fun builtinLen(args: List<Expression>, position: Position, program: Prog
 
 private fun builtinMkword(args: List<Expression>, position: Position, program: Program): NumericLiteralValue {
     if (args.size != 2)
-        throw SyntaxError("mkword requires lsb and msb arguments", position)
-    val constLsb = args[0].constValue(program) ?: throw NotConstArgumentException()
-    val constMsb = args[1].constValue(program) ?: throw NotConstArgumentException()
+        throw SyntaxError("mkword requires msb and lsb arguments", position)
+    val constMsb = args[0].constValue(program) ?: throw NotConstArgumentException()
+    val constLsb = args[1].constValue(program) ?: throw NotConstArgumentException()
     val result = (constMsb.number.toInt() shl 8) or constLsb.number.toInt()
     return NumericLiteralValue(DataType.UWORD, result, position)
 }
@@ -312,7 +342,7 @@ private fun builtinSin8(args: List<Expression>, position: Position, program: Pro
         throw SyntaxError("sin8 requires one argument", position)
     val constval = args[0].constValue(program) ?: throw NotConstArgumentException()
     val rad = constval.number.toDouble() /256.0 * 2.0 * PI
-    return NumericLiteralValue(DataType.BYTE, (127.0 * sin(rad)).toShort(), position)
+    return NumericLiteralValue(DataType.BYTE, (127.0 * sin(rad)).toInt().toShort(), position)
 }
 
 private fun builtinSin8u(args: List<Expression>, position: Position, program: Program): NumericLiteralValue {
@@ -320,7 +350,7 @@ private fun builtinSin8u(args: List<Expression>, position: Position, program: Pr
         throw SyntaxError("sin8u requires one argument", position)
     val constval = args[0].constValue(program) ?: throw NotConstArgumentException()
     val rad = constval.number.toDouble() /256.0 * 2.0 * PI
-    return NumericLiteralValue(DataType.UBYTE, (128.0 + 127.5 * sin(rad)).toShort(), position)
+    return NumericLiteralValue(DataType.UBYTE, (128.0 + 127.5 * sin(rad)).toInt().toShort(), position)
 }
 
 private fun builtinCos8(args: List<Expression>, position: Position, program: Program): NumericLiteralValue {
@@ -328,7 +358,7 @@ private fun builtinCos8(args: List<Expression>, position: Position, program: Pro
         throw SyntaxError("cos8 requires one argument", position)
     val constval = args[0].constValue(program) ?: throw NotConstArgumentException()
     val rad = constval.number.toDouble() /256.0 * 2.0 * PI
-    return NumericLiteralValue(DataType.BYTE, (127.0 * cos(rad)).toShort(), position)
+    return NumericLiteralValue(DataType.BYTE, (127.0 * cos(rad)).toInt().toShort(), position)
 }
 
 private fun builtinCos8u(args: List<Expression>, position: Position, program: Program): NumericLiteralValue {
@@ -336,7 +366,7 @@ private fun builtinCos8u(args: List<Expression>, position: Position, program: Pr
         throw SyntaxError("cos8u requires one argument", position)
     val constval = args[0].constValue(program) ?: throw NotConstArgumentException()
     val rad = constval.number.toDouble() /256.0 * 2.0 * PI
-    return NumericLiteralValue(DataType.UBYTE, (128.0 + 127.5 * cos(rad)).toShort(), position)
+    return NumericLiteralValue(DataType.UBYTE, (128.0 + 127.5 * cos(rad)).toInt().toShort(), position)
 }
 
 private fun builtinSin16(args: List<Expression>, position: Position, program: Program): NumericLiteralValue {
@@ -375,7 +405,7 @@ private fun builtinSgn(args: List<Expression>, position: Position, program: Prog
     if (args.size != 1)
         throw SyntaxError("sgn requires one argument", position)
     val constval = args[0].constValue(program) ?: throw NotConstArgumentException()
-    return NumericLiteralValue(DataType.BYTE, constval.number.toDouble().sign.toShort(), position)
+    return NumericLiteralValue(DataType.BYTE, constval.number.toDouble().sign.toInt().toShort(), position)
 }
 
 private fun numericLiteral(value: Number, position: Position): NumericLiteralValue {
@@ -387,8 +417,8 @@ private fun numericLiteral(value: Number, position: Position): NumericLiteralVal
                 floatNum
 
     return when(tweakedValue) {
-        is Int -> NumericLiteralValue.optimalNumeric(value.toInt(), position)
-        is Short -> NumericLiteralValue.optimalNumeric(value.toInt(), position)
+        is Int -> NumericLiteralValue.optimalInteger(value.toInt(), position)
+        is Short -> NumericLiteralValue.optimalInteger(value.toInt(), position)
         is Byte -> NumericLiteralValue(DataType.UBYTE, value.toShort(), position)
         is Double -> NumericLiteralValue(DataType.FLOAT, value.toDouble(), position)
         is Float -> NumericLiteralValue(DataType.FLOAT, value.toDouble(), position)

compiler/src/prog8/optimizer/AssignmentTransformer.kt

@@ -1,157 +0,0 @@
-package prog8.optimizer
-
-import prog8.ast.Node
-import prog8.ast.Program
-import prog8.ast.base.ErrorReporter
-import prog8.ast.expressions.BinaryExpression
-import prog8.ast.processing.AstWalker
-import prog8.ast.processing.IAstModification
-import prog8.ast.statements.Assignment
-import prog8.ast.statements.PostIncrDecr
-
-
-
-internal class AssignmentTransformer(val program: Program, val errors: ErrorReporter) : AstWalker() {
-
-    var optimizationsDone: Int = 0
-    private val noModifications = emptyList<IAstModification>()
-
-    override fun before(assignment: Assignment, parent: Node): Iterable<IAstModification> {
-        // modify A = A + 5 back into augmented form A += 5 for easier code generation for optimized in-place assignments
-        // also to put code generation stuff together, single value assignment (A = 5) is converted to a special
-        // augmented form as wel (with the operator "setvalue")
-        if (assignment.aug_op == null) {
-            val binExpr = assignment.value as? BinaryExpression
-            if (binExpr != null) {
-                if (assignment.target.isSameAs(binExpr.left)) {
-                    assignment.value = binExpr.right
-                    assignment.aug_op = binExpr.operator + "="
-                    assignment.value.parent = assignment
-                    optimizationsDone++
-                    return noModifications
-                }
-            }
-            assignment.aug_op = "setvalue"
-            optimizationsDone++
-        } else if(assignment.aug_op == "+=") {
-            val binExpr = assignment.value as? BinaryExpression
-            if (binExpr != null) {
-                val leftnum = binExpr.left.constValue(program)?.number?.toDouble()
-                val rightnum = binExpr.right.constValue(program)?.number?.toDouble()
-                if(binExpr.operator == "+") {
-                    when {
-                        leftnum == 1.0 -> {
-                            optimizationsDone++
-                            return listOf(IAstModification.SwapOperands(binExpr))
-                        }
-                        leftnum == 2.0 -> {
-                            optimizationsDone++
-                            return listOf(IAstModification.SwapOperands(binExpr))
-                        }
-                        rightnum == 1.0 -> {
-                            // x += y + 1  -> x += y ,  x++
-                            return listOf(
-                                    IAstModification.ReplaceNode(assignment.value, binExpr.left, assignment),
-                                    IAstModification.InsertAfter(assignment, PostIncrDecr(assignment.target, "++", assignment.position), parent)
-                            )
-                        }
-                        rightnum == 2.0 -> {
-                            // x += y + 2  -> x += y ,  x++,  x++
-                            return listOf(
-                                    IAstModification.ReplaceNode(assignment.value, binExpr.left, assignment),
-                                    IAstModification.InsertAfter(assignment, PostIncrDecr(assignment.target, "++", assignment.position), parent),
-                                    IAstModification.InsertAfter(assignment, PostIncrDecr(assignment.target, "++", assignment.position), parent)
-                            )
-                        }
-                    }
-                } else if(binExpr.operator == "-") {
-                    when {
-                        leftnum == 1.0 -> {
-                            optimizationsDone++
-                            return listOf(IAstModification.SwapOperands(binExpr))
-                        }
-                        leftnum == 2.0 -> {
-                            optimizationsDone++
-                            return listOf(IAstModification.SwapOperands(binExpr))
-                        }
-                        rightnum == 1.0 -> {
-                            // x += y - 1  -> x += y ,  x--
-                            return listOf(
-                                    IAstModification.ReplaceNode(assignment.value, binExpr.left, assignment),
-                                    IAstModification.InsertAfter(assignment, PostIncrDecr(assignment.target, "--", assignment.position), parent)
-                            )
-                        }
-                        rightnum == 2.0 -> {
-                            // x += y - 2  -> x += y ,  x--,  x--
-                            return listOf(
-                                    IAstModification.ReplaceNode(assignment.value, binExpr.left, assignment),
-                                    IAstModification.InsertAfter(assignment, PostIncrDecr(assignment.target, "--", assignment.position), parent),
-                                    IAstModification.InsertAfter(assignment, PostIncrDecr(assignment.target, "--", assignment.position), parent)
-                            )
-                        }
-                    }
-                }
-            }
-        } else if(assignment.aug_op == "-=") {
-            val binExpr = assignment.value as? BinaryExpression
-            if (binExpr != null) {
-                val leftnum = binExpr.left.constValue(program)?.number?.toDouble()
-                val rightnum = binExpr.right.constValue(program)?.number?.toDouble()
-                if(binExpr.operator == "+") {
-                    when {
-                        leftnum == 1.0 -> {
-                            optimizationsDone++
-                            return listOf(IAstModification.SwapOperands(binExpr))
-                        }
-                        leftnum == 2.0 -> {
-                            optimizationsDone++
-                            return listOf(IAstModification.SwapOperands(binExpr))
-                        }
-                        rightnum == 1.0 -> {
-                            // x -= y + 1  -> x -= y ,  x--
-                            return listOf(
-                                    IAstModification.ReplaceNode(assignment.value, binExpr.left, assignment),
-                                    IAstModification.InsertAfter(assignment, PostIncrDecr(assignment.target, "--", assignment.position), parent)
-                            )
-                        }
-                        rightnum == 2.0 -> {
-                            // x -= y + 2  -> x -= y ,  x--,  x--
-                            return listOf(
-                                    IAstModification.ReplaceNode(assignment.value, binExpr.left, assignment),
-                                    IAstModification.InsertAfter(assignment, PostIncrDecr(assignment.target, "--", assignment.position), parent),
-                                    IAstModification.InsertAfter(assignment, PostIncrDecr(assignment.target, "--", assignment.position), parent)
-                            )
-                        }
-                    }
-                } else if(binExpr.operator == "-") {
-                    when {
-                        leftnum == 1.0 -> {
-                            optimizationsDone++
-                            return listOf(IAstModification.SwapOperands(binExpr))
-                        }
-                        leftnum == 2.0 -> {
-                            optimizationsDone++
-                            return listOf(IAstModification.SwapOperands(binExpr))
-                        }
-                        rightnum == 1.0 -> {
-                            // x -= y - 1  -> x -= y ,  x++
-                            return listOf(
-                                    IAstModification.ReplaceNode(assignment.value, binExpr.left, assignment),
-                                    IAstModification.InsertAfter(assignment, PostIncrDecr(assignment.target, "++", assignment.position), parent)
-                            )
-                        }
-                        rightnum == 2.0 -> {
-                            // x -= y - 2  -> x -= y ,  x++,  x++
-                            return listOf(
-                                    IAstModification.ReplaceNode(assignment.value, binExpr.left, assignment),
-                                    IAstModification.InsertAfter(assignment, PostIncrDecr(assignment.target, "++", assignment.position), parent),
-                                    IAstModification.InsertAfter(assignment, PostIncrDecr(assignment.target, "++", assignment.position), parent)
-                            )
-                        }
-                    }
-                }
-            }
-        }
-        return noModifications
-    }
-}

compiler/src/prog8/optimizer/CallGraph.kt

@@ -14,8 +14,7 @@ import prog8.compiler.loadAsmIncludeFile
 
 private val alwaysKeepSubroutines = setOf(
         Pair("main", "start"),
-        Pair("irq", "irq"),
-        Pair("prog8_lib", "init_system")
+        Pair("irq", "irq")
 )
 
 private val asmJumpRx = Regex("""[\-+a-zA-Z0-9_ \t]+(jmp|jsr)[ \t]+(\S+).*""", RegexOption.IGNORE_CASE)

compiler/src/prog8/optimizer/ConstExprEvaluator.kt

@@ -132,11 +132,11 @@ class ConstExprEvaluator {
     private fun bitwiseand(left: NumericLiteralValue, right: NumericLiteralValue): NumericLiteralValue {
         if(left.type== DataType.UBYTE) {
             if(right.type in IntegerDatatypes) {
-                return NumericLiteralValue(DataType.UBYTE, (left.number.toInt() or (right.number.toInt() and 255)).toShort(), left.position)
+                return NumericLiteralValue(DataType.UBYTE, (left.number.toInt() and (right.number.toInt() and 255)).toShort(), left.position)
             }
         } else if(left.type== DataType.UWORD) {
             if(right.type in IntegerDatatypes) {
-                return NumericLiteralValue(DataType.UWORD, left.number.toInt() or right.number.toInt(), left.position)
+                return NumericLiteralValue(DataType.UWORD, left.number.toInt() and right.number.toInt(), left.position)
             }
         }
         throw ExpressionError("cannot calculate $left & $right", left.position)
@@ -163,7 +163,7 @@ class ConstExprEvaluator {
         val error = "cannot add $left and $right"
         return when (left.type) {
             in IntegerDatatypes -> when (right.type) {
-                in IntegerDatatypes -> NumericLiteralValue.optimalNumeric(left.number.toInt() + right.number.toInt(), left.position)
+                in IntegerDatatypes -> NumericLiteralValue.optimalInteger(left.number.toInt() + right.number.toInt(), left.position)
                 DataType.FLOAT -> NumericLiteralValue(DataType.FLOAT, left.number.toInt() + right.number.toDouble(), left.position)
                 else -> throw ExpressionError(error, left.position)
             }
@@ -180,7 +180,7 @@ class ConstExprEvaluator {
         val error = "cannot subtract $left and $right"
         return when (left.type) {
             in IntegerDatatypes -> when (right.type) {
-                in IntegerDatatypes -> NumericLiteralValue.optimalNumeric(left.number.toInt() - right.number.toInt(), left.position)
+                in IntegerDatatypes -> NumericLiteralValue.optimalInteger(left.number.toInt() - right.number.toInt(), left.position)
                 DataType.FLOAT -> NumericLiteralValue(DataType.FLOAT, left.number.toInt() - right.number.toDouble(), left.position)
                 else -> throw ExpressionError(error, left.position)
             }
@@ -197,7 +197,7 @@ class ConstExprEvaluator {
         val error = "cannot multiply ${left.type} and ${right.type}"
         return when (left.type) {
             in IntegerDatatypes -> when (right.type) {
-                in IntegerDatatypes -> NumericLiteralValue.optimalNumeric(left.number.toInt() * right.number.toInt(), left.position)
+                in IntegerDatatypes -> NumericLiteralValue.optimalInteger(left.number.toInt() * right.number.toInt(), left.position)
                 DataType.FLOAT -> NumericLiteralValue(DataType.FLOAT, left.number.toInt() * right.number.toDouble(), left.position)
                 else -> throw ExpressionError(error, left.position)
             }
@@ -220,7 +220,7 @@ class ConstExprEvaluator {
                 in IntegerDatatypes -> {
                     if(right.number.toInt()==0) divideByZeroError(right.position)
                     val result: Int = left.number.toInt() / right.number.toInt()
-                    NumericLiteralValue.optimalNumeric(result, left.position)
+                    NumericLiteralValue.optimalInteger(result, left.position)
                 }
                 DataType.FLOAT -> {
                     if(right.number.toDouble()==0.0) divideByZeroError(right.position)

compiler/src/prog8/optimizer/ConstantFoldingOptimizer.kt

@@ -56,7 +56,7 @@ internal class ConstantIdentifierReplacer(private val program: Program, private
                         ))
                     }
                 }
-                else if(decl.arraysize?.size()==null) {
+                else if(decl.arraysize?.constIndex()==null) {
                     val size = decl.arraysize!!.index.constValue(program)
                     if(size!=null) {
                         return listOf(IAstModification.SetExpression(
@@ -81,7 +81,7 @@ internal class ConstantIdentifierReplacer(private val program: Program, private
                     val rangeExpr = decl.value as? RangeExpr
                     if(rangeExpr!=null) {
                         // convert the initializer range expression to an actual array
-                        val declArraySize = decl.arraysize?.size()
+                        val declArraySize = decl.arraysize?.constIndex()
                         if(declArraySize!=null && declArraySize!=rangeExpr.size())
                             errors.err("range expression size doesn't match declared array size", decl.value?.position!!)
                         val constRange = rangeExpr.toConstantIntegerRange()
@@ -101,7 +101,7 @@ internal class ConstantIdentifierReplacer(private val program: Program, private
                     }
                     if(numericLv!=null && numericLv.type==DataType.FLOAT)
                         errors.err("arraysize requires only integers here", numericLv.position)
-                    val size = decl.arraysize?.size() ?: return noModifications
+                    val size = decl.arraysize?.constIndex() ?: return noModifications
                     if (rangeExpr==null && numericLv!=null) {
                         // arraysize initializer is empty or a single int, and we know the size; create the arraysize.
                         val fillvalue = numericLv.number.toInt()
@@ -125,18 +125,18 @@ 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) as Expression}.toTypedArray()
+                        val array = Array(size) {fillvalue}.map { NumericLiteralValue(ArrayElementTypes.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))
                     }
                 }
                 DataType.ARRAY_F  -> {
-                    val size = decl.arraysize?.size() ?: return noModifications
+                    val size = decl.arraysize?.constIndex() ?: return noModifications
                     val litval = decl.value as? NumericLiteralValue
                     val rangeExpr = decl.value as? RangeExpr
                     if(rangeExpr!=null) {
                         // convert the initializer range expression to an actual array of floats
-                        val declArraySize = decl.arraysize?.size()
+                        val declArraySize = decl.arraysize?.constIndex()
                         if(declArraySize!=null && declArraySize!=rangeExpr.size())
                             errors.err("range expression size doesn't match declared array size", decl.value?.position!!)
                         val constRange = rangeExpr.toConstantIntegerRange()
@@ -150,11 +150,11 @@ internal class ConstantIdentifierReplacer(private val program: Program, private
                     if(rangeExpr==null && litval!=null) {
                         // arraysize initializer is a single int, and we know the size.
                         val fillvalue = litval.number.toDouble()
-                        if (fillvalue < CompilationTarget.machine.FLOAT_MAX_NEGATIVE || fillvalue > CompilationTarget.machine.FLOAT_MAX_POSITIVE)
+                        if (fillvalue < CompilationTarget.instance.machine.FLOAT_MAX_NEGATIVE || fillvalue > CompilationTarget.instance.machine.FLOAT_MAX_POSITIVE)
                             errors.err("float value overflow", litval.position)
                         else {
                             // create the array itself, filled with the fillvalue.
-                            val array = Array(size) {fillvalue}.map { NumericLiteralValue(DataType.FLOAT, it, litval.position) as Expression}.toTypedArray()
+                            val array = Array(size) {fillvalue}.map { NumericLiteralValue(DataType.FLOAT, it, litval.position) }.toTypedArray<Expression>()
                             val refValue = ArrayLiteralValue(InferredTypes.InferredType.known(DataType.ARRAY_F), array, position = litval.position)
                             return listOf(IAstModification.ReplaceNode(decl.value!!, refValue, decl))
                         }
@@ -171,7 +171,9 @@ internal class ConstantIdentifierReplacer(private val program: Program, private
         if(declValue!=null && decl.type==VarDeclType.VAR
                 && declValue is NumericLiteralValue && !declValue.inferType(program).istype(decl.datatype)) {
             // cast the numeric literal to the appropriate datatype of the variable
-            return listOf(IAstModification.ReplaceNode(decl.value!!, declValue.cast(decl.datatype), decl))
+            val cast = declValue.cast(decl.datatype)
+            if(cast.isValid)
+                return listOf(IAstModification.ReplaceNode(decl.value!!, cast.valueOrZero(), decl))
         }
 
         return noModifications
@@ -179,7 +181,7 @@ internal class ConstantIdentifierReplacer(private val program: Program, private
 }
 
 
-internal class ConstantFoldingOptimizer(private val program: Program, private val errors: ErrorReporter) : AstWalker() {
+internal class ConstantFoldingOptimizer(private val program: Program) : AstWalker() {
     private val noModifications = emptyList<IAstModification>()
 
     override fun before(memread: DirectMemoryRead, parent: Node): Iterable<IAstModification> {
@@ -203,7 +205,7 @@ internal class ConstantFoldingOptimizer(private val program: Program, private va
                 "-" -> when (subexpr.type) {
                     in IntegerDatatypes -> {
                         listOf(IAstModification.ReplaceNode(expr,
-                                NumericLiteralValue.optimalNumeric(-subexpr.number.toInt(), subexpr.position),
+                                NumericLiteralValue.optimalInteger(-subexpr.number.toInt(), subexpr.position),
                                 parent))
                     }
                     DataType.FLOAT -> {
@@ -216,7 +218,7 @@ internal class ConstantFoldingOptimizer(private val program: Program, private va
                 "~" -> when (subexpr.type) {
                     in IntegerDatatypes -> {
                         listOf(IAstModification.ReplaceNode(expr,
-                                NumericLiteralValue.optimalNumeric(subexpr.number.toInt().inv(), subexpr.position),
+                                NumericLiteralValue.optimalInteger(subexpr.number.toInt().inv(), subexpr.position),
                                 parent))
                     }
                     else -> throw ExpressionError("can only take bitwise inversion of int", subexpr.position)
@@ -273,11 +275,8 @@ internal class ConstantFoldingOptimizer(private val program: Program, private va
         // const fold when both operands are a const
         if(leftconst != null && rightconst != null) {
             val evaluator = ConstExprEvaluator()
-            return listOf(IAstModification.ReplaceNode(
-                    expr,
-                    evaluator.evaluate(leftconst, expr.operator, rightconst),
-                    parent
-            ))
+            val result = evaluator.evaluate(leftconst, expr.operator, rightconst)
+            return listOf(IAstModification.ReplaceNode(expr, result, parent))
         }
 
         return noModifications
@@ -319,21 +318,24 @@ internal class ConstantFoldingOptimizer(private val program: Program, private va
     }
 
     override fun after(forLoop: ForLoop, parent: Node): Iterable<IAstModification> {
-        fun adjustRangeDt(rangeFrom: NumericLiteralValue, targetDt: DataType, rangeTo: NumericLiteralValue, stepLiteral: NumericLiteralValue?, range: RangeExpr): RangeExpr {
-            val newFrom: NumericLiteralValue
-            val newTo: NumericLiteralValue
-            try {
-                newFrom = rangeFrom.cast(targetDt)
-                newTo = rangeTo.cast(targetDt)
-            } catch (x: ExpressionError) {
-                return range
-            }
-            val newStep: Expression = try {
-                stepLiteral?.cast(targetDt)?: range.step
-            } catch(ee: ExpressionError) {
-                range.step
-            }
-            return RangeExpr(newFrom, newTo, newStep, range.position)
+        fun adjustRangeDt(rangeFrom: NumericLiteralValue, targetDt: DataType, rangeTo: NumericLiteralValue, stepLiteral: NumericLiteralValue?, range: RangeExpr): RangeExpr? {
+            val fromCast = rangeFrom.cast(targetDt)
+            val toCast = rangeTo.cast(targetDt)
+            if(!fromCast.isValid || !toCast.isValid)
+                return null
+
+            val newStep =
+                if(stepLiteral!=null) {
+                    val stepCast = stepLiteral.cast(targetDt)
+                    if(stepCast.isValid)
+                        stepCast.valueOrZero()
+                    else
+                        range.step
+                } else {
+                    range.step
+                }
+
+            return RangeExpr(fromCast.valueOrZero(), toCast.valueOrZero(), newStep, range.position)
         }
 
         // adjust the datatype of a range expression in for loops to the loop variable.
@@ -349,28 +351,32 @@ internal class ConstantFoldingOptimizer(private val program: Program, private va
                 if(rangeFrom.type!= DataType.UBYTE) {
                     // attempt to translate the iterable into ubyte values
                     val newIter = adjustRangeDt(rangeFrom, loopvar.datatype, rangeTo, stepLiteral, iterableRange)
-                    return listOf(IAstModification.ReplaceNode(forLoop.iterable, newIter, forLoop))
+                    if(newIter!=null)
+                        return listOf(IAstModification.ReplaceNode(forLoop.iterable, newIter, forLoop))
                 }
             }
             DataType.BYTE -> {
                 if(rangeFrom.type!= DataType.BYTE) {
                     // attempt to translate the iterable into byte values
                     val newIter = adjustRangeDt(rangeFrom, loopvar.datatype, rangeTo, stepLiteral, iterableRange)
-                    return listOf(IAstModification.ReplaceNode(forLoop.iterable, newIter, forLoop))
+                    if(newIter!=null)
+                        return listOf(IAstModification.ReplaceNode(forLoop.iterable, newIter, forLoop))
                 }
             }
             DataType.UWORD -> {
                 if(rangeFrom.type!= DataType.UWORD) {
                     // attempt to translate the iterable into uword values
                     val newIter = adjustRangeDt(rangeFrom, loopvar.datatype, rangeTo, stepLiteral, iterableRange)
-                    return listOf(IAstModification.ReplaceNode(forLoop.iterable, newIter, forLoop))
+                    if(newIter!=null)
+                        return listOf(IAstModification.ReplaceNode(forLoop.iterable, newIter, forLoop))
                 }
             }
             DataType.WORD -> {
                 if(rangeFrom.type!= DataType.WORD) {
                     // attempt to translate the iterable into word values
                     val newIter = adjustRangeDt(rangeFrom, loopvar.datatype, rangeTo, stepLiteral, iterableRange)
-                    return listOf(IAstModification.ReplaceNode(forLoop.iterable, newIter, forLoop))
+                    if(newIter!=null)
+                        return listOf(IAstModification.ReplaceNode(forLoop.iterable, newIter, forLoop))
                 }
             }
             else -> throw FatalAstException("invalid loopvar datatype $loopvar")
@@ -379,6 +385,19 @@ internal class ConstantFoldingOptimizer(private val program: Program, private va
         return noModifications
     }
 
+    override fun after(decl: VarDecl, parent: Node): Iterable<IAstModification> {
+        val numval = decl.value as? NumericLiteralValue
+        if(decl.type== VarDeclType.CONST && numval!=null) {
+            val valueDt = numval.inferType(program)
+            if(!valueDt.istype(decl.datatype)) {
+                val cast = numval.cast(decl.datatype)
+                if(cast.isValid)
+                    return listOf(IAstModification.ReplaceNode(numval, cast.valueOrZero(), decl))
+            }
+        }
+        return noModifications
+    }
+
     private class ShuffleOperands(val expr: BinaryExpression,
                                   val exprOperator: String?,
                                   val subExpr: BinaryExpression,
@@ -406,8 +425,9 @@ internal class ConstantFoldingOptimizer(private val program: Program, private va
         // todo: this implements only a small set of possible reorderings at this time
         if(expr.operator==subExpr.operator) {
             // both operators are the same.
-            // If + or *,  we can simply shuffle the const operands around to optimize.
-            if(expr.operator=="+" || expr.operator=="*") {
+
+            // If associative,  we can simply shuffle the const operands around to optimize.
+            if(expr.operator in associativeOperators) {
                 return if(leftIsConst) {
                     if(subleftIsConst)
                         ShuffleOperands(expr, null, subExpr, subExpr.right, null, null, expr.left)

compiler/src/prog8/optimizer/ExpressionSimplifier.kt

@@ -6,7 +6,6 @@ import prog8.ast.base.*
 import prog8.ast.expressions.*
 import prog8.ast.processing.AstWalker
 import prog8.ast.processing.IAstModification
-import prog8.ast.statements.Assignment
 import kotlin.math.abs
 import kotlin.math.log2
 import kotlin.math.pow
@@ -24,12 +23,6 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
     private val negativePowersOfTwo = powersOfTwo.map { -it }.toSet()
     private val noModifications = emptyList<IAstModification>()
 
-    override fun after(assignment: Assignment, parent: Node): Iterable<IAstModification> {
-        if (assignment.aug_op != null)
-            throw FatalAstException("augmented assignments should have been converted to normal assignments before this optimizer: $assignment")
-        return noModifications
-    }
-
     override fun after(typecast: TypecastExpression, parent: Node): Iterable<IAstModification> {
         val mods = mutableListOf<IAstModification>()
 
@@ -37,19 +30,22 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
         val literal = typecast.expression as? NumericLiteralValue
         if (literal != null) {
             val newLiteral = literal.cast(typecast.type)
-            if (newLiteral !== literal)
-                mods += IAstModification.ReplaceNode(typecast.expression, newLiteral, typecast)
+            if (newLiteral.isValid && newLiteral.valueOrZero() !== literal)
+                mods += IAstModification.ReplaceNode(typecast.expression, newLiteral.valueOrZero(), typecast)
         }
 
-        // remove redundant nested typecasts:
-        // if the typecast casts a value to the same type, remove the cast.
-        // if the typecast contains another typecast, remove the inner typecast.
+        // remove redundant nested typecasts
         val subTypecast = typecast.expression as? TypecastExpression
         if (subTypecast != null) {
-            mods += IAstModification.ReplaceNode(typecast.expression, subTypecast.expression, typecast)
+            // remove the sub-typecast if its datatype is larger than the outer typecast
+            if(subTypecast.type largerThan typecast.type) {
+                mods += IAstModification.ReplaceNode(typecast.expression, subTypecast.expression, typecast)
+            }
         } else {
-            if (typecast.expression.inferType(program).istype(typecast.type))
+            if (typecast.expression.inferType(program).istype(typecast.type)) {
+                // remove duplicate cast
                 mods += IAstModification.ReplaceNode(typecast, typecast.expression, parent)
+            }
         }
 
         return mods
@@ -301,6 +297,49 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
         return noModifications
     }
 
+    override fun after(functionCall: FunctionCall, parent: Node): Iterable<IAstModification> {
+        if(functionCall.target.nameInSource == listOf("lsb")) {
+            val arg = functionCall.args[0]
+            if(arg is TypecastExpression) {
+                val valueDt = arg.expression.inferType(program)
+                if (valueDt.istype(DataType.BYTE) || valueDt.istype(DataType.UBYTE)) {
+                    // useless lsb() of byte value that was casted to word
+                    return listOf(IAstModification.ReplaceNode(functionCall, arg.expression, parent))
+                }
+            } else {
+                val argDt = arg.inferType(program)
+                if (argDt.istype(DataType.BYTE) || argDt.istype(DataType.UBYTE)) {
+                    // useless lsb() of byte value
+                    return listOf(IAstModification.ReplaceNode(functionCall, arg, parent))
+                }
+            }
+        }
+        else if(functionCall.target.nameInSource == listOf("msb")) {
+            val arg = functionCall.args[0]
+            if(arg is TypecastExpression) {
+                val valueDt = arg.expression.inferType(program)
+                if (valueDt.istype(DataType.BYTE) || valueDt.istype(DataType.UBYTE)) {
+                    // useless msb() of byte value that was casted to word, replace with 0
+                    return listOf(IAstModification.ReplaceNode(
+                            functionCall,
+                            NumericLiteralValue(valueDt.typeOrElse(DataType.UBYTE), 0, arg.expression.position),
+                            parent))
+                }
+            } else {
+                val argDt = arg.inferType(program)
+                if (argDt.istype(DataType.BYTE) || argDt.istype(DataType.UBYTE)) {
+                    // useless msb() of byte value, replace with 0
+                    return listOf(IAstModification.ReplaceNode(
+                            functionCall,
+                            NumericLiteralValue(argDt.typeOrElse(DataType.UBYTE), 0, arg.position),
+                            parent))
+                }
+            }
+        }
+
+        return noModifications
+    }
+
     private fun determineY(x: Expression, subBinExpr: BinaryExpression): Expression? {
         return when {
             subBinExpr.left isSameAs x -> subBinExpr.right
@@ -590,10 +629,10 @@ internal class ExpressionSimplifier(private val program: Program) : AstWalker()
                 } else if (amount >= 8) {
                     val lsb = TypecastExpression(expr.left, DataType.UBYTE, true, expr.position)
                     if (amount == 8) {
-                        return FunctionCall(IdentifierReference(listOf("mkword"), expr.position), mutableListOf(NumericLiteralValue.optimalInteger(0, expr.position), lsb), expr.position)
+                        return FunctionCall(IdentifierReference(listOf("mkword"), expr.position), mutableListOf(lsb, NumericLiteralValue.optimalInteger(0, expr.position)), expr.position)
                     }
                     val shifted = BinaryExpression(lsb, "<<", NumericLiteralValue.optimalInteger(amount - 8, expr.position), expr.position)
-                    return FunctionCall(IdentifierReference(listOf("mkword"), expr.position), mutableListOf(NumericLiteralValue.optimalInteger(0, expr.position), shifted), expr.position)
+                    return FunctionCall(IdentifierReference(listOf("mkword"), expr.position), mutableListOf(shifted, NumericLiteralValue.optimalInteger(0, expr.position)), expr.position)
                 }
             }
             else -> {

compiler/src/prog8/optimizer/Extensions.kt

@@ -10,7 +10,7 @@ internal fun Program.constantFold(errors: ErrorReporter) {
     if(errors.isEmpty()) {
         replacer.applyModifications()
 
-        val optimizer = ConstantFoldingOptimizer(this, errors)
+        val optimizer = ConstantFoldingOptimizer(this)
         optimizer.visit(this)
         while (errors.isEmpty() && optimizer.applyModifications() > 0) {
             optimizer.visit(this)

compiler/src/prog8/optimizer/StatementOptimizer.kt

@@ -14,11 +14,6 @@ import prog8.functions.BuiltinFunctions
 import kotlin.math.floor
 
 
-/*
-    TODO: remove unreachable code after return and exit()
-*/
-
-
 internal class StatementOptimizer(private val program: Program,
                                   private val errors: ErrorReporter) : AstWalker() {
 
@@ -105,32 +100,34 @@ internal class StatementOptimizer(private val program: Program,
             }
             if(stringVar!=null) {
                 val vardecl = stringVar.targetVarDecl(program.namespace)!!
-                val string = vardecl.value!! as StringLiteralValue
-                val pos = functionCallStatement.position
-                if(string.value.length==1) {
-                    val firstCharEncoded = CompilationTarget.encodeString(string.value, string.altEncoding)[0]
-                    val chrout = FunctionCallStatement(
-                            IdentifierReference(listOf("c64", "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 = CompilationTarget.encodeString(string.value.take(2), string.altEncoding)
-                    val chrout1 = FunctionCallStatement(
-                            IdentifierReference(listOf("c64", "CHROUT"), pos),
-                            mutableListOf(NumericLiteralValue(DataType.UBYTE, firstTwoCharsEncoded[0].toInt(), pos)),
-                            functionCallStatement.void, pos
-                    )
-                    val chrout2 = FunctionCallStatement(
-                            IdentifierReference(listOf("c64", "CHROUT"), pos),
-                            mutableListOf(NumericLiteralValue(DataType.UBYTE, firstTwoCharsEncoded[1].toInt(), pos)),
-                            functionCallStatement.void, pos
-                    )
-                    val anonscope = AnonymousScope(mutableListOf(), pos)
-                    anonscope.statements.add(chrout1)
-                    anonscope.statements.add(chrout2)
-                    return listOf(IAstModification.ReplaceNode(functionCallStatement, anonscope, parent))
+                val string = vardecl.value as? StringLiteralValue
+                if(string!=null) {
+                    val pos = functionCallStatement.position
+                    if (string.value.length == 1) {
+                        val firstCharEncoded = CompilationTarget.instance.encodeString(string.value, string.altEncoding)[0]
+                        val chrout = FunctionCallStatement(
+                                IdentifierReference(listOf("c64", "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 = CompilationTarget.instance.encodeString(string.value.take(2), string.altEncoding)
+                        val chrout1 = FunctionCallStatement(
+                                IdentifierReference(listOf("c64", "CHROUT"), pos),
+                                mutableListOf(NumericLiteralValue(DataType.UBYTE, firstTwoCharsEncoded[0].toInt(), pos)),
+                                functionCallStatement.void, pos
+                        )
+                        val chrout2 = FunctionCallStatement(
+                                IdentifierReference(listOf("c64", "CHROUT"), pos),
+                                mutableListOf(NumericLiteralValue(DataType.UBYTE, firstTwoCharsEncoded[1].toInt(), pos)),
+                                functionCallStatement.void, pos
+                        )
+                        val anonscope = AnonymousScope(mutableListOf(), pos)
+                        anonscope.statements.add(chrout1)
+                        anonscope.statements.add(chrout2)
+                        return listOf(IAstModification.ReplaceNode(functionCallStatement, anonscope, parent))
+                    }
                 }
             }
         }
@@ -139,7 +136,7 @@ internal class StatementOptimizer(private val program: Program,
         val subroutine = functionCallStatement.target.targetSubroutine(program.namespace)
         if(subroutine!=null) {
             val first = subroutine.statements.asSequence().filterNot { it is VarDecl || it is Directive }.firstOrNull()
-            if(first is ReturnFromIrq || first is Return)
+            if(first is Return)
                 return listOf(IAstModification.Remove(functionCallStatement, parent))
         }
 
@@ -211,7 +208,7 @@ internal class StatementOptimizer(private val program: Program,
                 // for loop over a (constant) range of just a single value-- optimize the loop away
                 // loopvar/reg = range value , follow by block
                 val scope = AnonymousScope(mutableListOf(), forLoop.position)
-                scope.statements.add(Assignment(AssignTarget(forLoop.loopVar, null, null, forLoop.position), null, range.from, forLoop.position))
+                scope.statements.add(Assignment(AssignTarget(forLoop.loopVar, null, null, forLoop.position), range.from, forLoop.position))
                 scope.statements.addAll(forLoop.body.statements)
                 return listOf(IAstModification.ReplaceNode(forLoop, scope, parent))
             }
@@ -223,23 +220,23 @@ internal class StatementOptimizer(private val program: Program,
                 val size = sv.value.length
                 if(size==1) {
                     // loop over string of length 1 -> just assign the single character
-                    val character = CompilationTarget.encodeString(sv.value, sv.altEncoding)[0]
+                    val character = CompilationTarget.instance.encodeString(sv.value, sv.altEncoding)[0]
                     val byte = NumericLiteralValue(DataType.UBYTE, character, iterable.position)
                     val scope = AnonymousScope(mutableListOf(), forLoop.position)
-                    scope.statements.add(Assignment(AssignTarget(forLoop.loopVar, null, null, forLoop.position), null, byte, forLoop.position))
+                    scope.statements.add(Assignment(AssignTarget(forLoop.loopVar, null, null, forLoop.position), byte, forLoop.position))
                     scope.statements.addAll(forLoop.body.statements)
                     return listOf(IAstModification.ReplaceNode(forLoop, scope, parent))
                 }
             }
             else if(iterable.datatype in ArrayDatatypes) {
-                val size = iterable.arraysize!!.size()
+                val size = iterable.arraysize!!.constIndex()
                 if(size==1) {
                     // loop over array of length 1 -> just assign the single value
                     val av = (iterable.value as ArrayLiteralValue).value[0].constValue(program)?.number
                     if(av!=null) {
                         val scope = AnonymousScope(mutableListOf(), forLoop.position)
                         scope.statements.add(Assignment(
-                                AssignTarget(forLoop.loopVar, null, null, forLoop.position), null, NumericLiteralValue.optimalInteger(av.toInt(), iterable.position),
+                                AssignTarget(forLoop.loopVar, null, null, forLoop.position), NumericLiteralValue.optimalInteger(av.toInt(), iterable.position),
                                 forLoop.position))
                         scope.statements.addAll(forLoop.body.statements)
                         return listOf(IAstModification.ReplaceNode(forLoop, scope, parent))
@@ -255,9 +252,9 @@ internal class StatementOptimizer(private val program: Program,
         val constvalue = untilLoop.untilCondition.constValue(program)
         if(constvalue!=null) {
             if(constvalue.asBooleanValue) {
-                // always true -> keep only the statement block (if there are no continue and break statements)
+                // always true -> keep only the statement block (if there are no break statements)
                 errors.warn("condition is always true", untilLoop.untilCondition.position)
-                if(!hasContinueOrBreak(untilLoop.body))
+                if(!hasBreak(untilLoop.body))
                     return listOf(IAstModification.ReplaceNode(untilLoop, untilLoop.body, parent))
             } else {
                 // always false
@@ -296,8 +293,10 @@ internal class StatementOptimizer(private val program: Program,
                 errors.warn("iterations is always 0, removed loop", iter.position)
                 return listOf(IAstModification.Remove(repeatLoop, parent))
             }
-            if (iterations == 1)
+            if (iterations == 1) {
                 errors.warn("iterations is always 1", iter.position)
+                return listOf(IAstModification.ReplaceNode(repeatLoop, repeatLoop.body, parent))
+            }
         }
         return noModifications
     }
@@ -324,21 +323,74 @@ internal class StatementOptimizer(private val program: Program,
         return noModifications
     }
 
-    override fun after(assignment: Assignment, parent: Node): Iterable<IAstModification> {
-        if(assignment.aug_op!=null)
-            throw FatalAstException("augmented assignments should have been converted to normal assignments before this optimizer: $assignment")
+    override fun before(assignment: Assignment, parent: Node): Iterable<IAstModification> {
 
-        // remove assignments to self
+        val binExpr = assignment.value as? BinaryExpression
+        if(binExpr!=null) {
+            if(binExpr.left isSameAs assignment.target) {
+                val rExpr = binExpr.right as? BinaryExpression
+                if(rExpr!=null) {
+                    val op1 = binExpr.operator
+                    val op2 = rExpr.operator
+
+                    if(rExpr.left is NumericLiteralValue && op2 in setOf("+", "*", "&", "|")) {
+                        // associative operator, make sure the constant numeric value is second (right)
+                        return listOf(IAstModification.SwapOperands(rExpr))
+                    }
+
+                    val rNum = (rExpr.right as? NumericLiteralValue)?.number
+                    if(rNum!=null) {
+                        if (op1 == "+" || op1 == "-") {
+                            if (op2 == "+") {
+                                // A = A +/- B + N
+                                val expr2 = BinaryExpression(binExpr.left, binExpr.operator, rExpr.left, binExpr.position)
+                                val addConstant = Assignment(
+                                        assignment.target,
+                                        BinaryExpression(binExpr.left, "+", rExpr.right, rExpr.position),
+                                        assignment.position
+                                )
+                                return listOf(
+                                        IAstModification.ReplaceNode(binExpr, expr2, binExpr.parent),
+                                        IAstModification.InsertAfter(assignment, addConstant, parent))
+                            } else if (op2 == "-") {
+                                // A = A +/- B - N
+                                val expr2 = BinaryExpression(binExpr.left, binExpr.operator, rExpr.left, binExpr.position)
+                                val subConstant = Assignment(
+                                        assignment.target,
+                                        BinaryExpression(binExpr.left, "-", rExpr.right, rExpr.position),
+                                        assignment.position
+                                )
+                                return listOf(
+                                        IAstModification.ReplaceNode(binExpr, expr2, binExpr.parent),
+                                        IAstModification.InsertAfter(assignment, subConstant, parent))
+                            }
+                        }
+                    }
+                }
+            }
+
+            if(binExpr.operator in associativeOperators && binExpr.right isSameAs assignment.target) {
+                // associative operator, swap the operands so that the assignment target is first (left)
+                // unless the other operand is the same in which case we don't swap (endless loop!)
+                if (!(binExpr.left isSameAs binExpr.right))
+                    return listOf(IAstModification.SwapOperands(binExpr))
+            }
+
+        }
+
+        return noModifications
+    }
+
+    override fun after(assignment: Assignment, parent: Node): Iterable<IAstModification> {
         if(assignment.target isSameAs assignment.value) {
-            if(assignment.target.isNotMemory(program.namespace))
-                return listOf(IAstModification.Remove(assignment, parent))
+            // remove assignment to self
+            return listOf(IAstModification.Remove(assignment, parent))
         }
 
         val targetIDt = assignment.target.inferType(program, assignment)
         if(!targetIDt.isKnown)
             throw FatalAstException("can't infer type of assignment target")
 
-
         // optimize binary expressions a bit
         val targetDt = targetIDt.typeOrElse(DataType.STRUCT)
         val bexpr=assignment.value as? BinaryExpression
@@ -354,8 +406,8 @@ internal class StatementOptimizer(private val program: Program,
                         if (cv == 0.0) {
                             return listOf(IAstModification.Remove(assignment, parent))
                         } else if (targetDt in IntegerDatatypes && floor(cv) == cv) {
-                            if ((vardeclDt == VarDeclType.MEMORY && cv in 1.0..3.0) || (vardeclDt != VarDeclType.MEMORY && cv in 1.0..8.0)) {
-                                // replace by several INCs (a bit less when dealing with memory targets)
+                            if (vardeclDt != VarDeclType.MEMORY && cv in 1.0..4.0) {
+                                // replace by several INCs if it's not a memory address (inc on a memory mapped register doesn't work very well)
                                 val incs = AnonymousScope(mutableListOf(), assignment.position)
                                 repeat(cv.toInt()) {
                                     incs.statements.add(PostIncrDecr(assignment.target, "++", assignment.position))
@@ -368,8 +420,8 @@ internal class StatementOptimizer(private val program: Program,
                         if (cv == 0.0) {
                             return listOf(IAstModification.Remove(assignment, parent))
                         } else if (targetDt in IntegerDatatypes && floor(cv) == cv) {
-                            if ((vardeclDt == VarDeclType.MEMORY && cv in 1.0..3.0) || (vardeclDt != VarDeclType.MEMORY && cv in 1.0..8.0)) {
-                                // replace by several DECs (a bit less when dealing with memory targets)
+                            if (vardeclDt != VarDeclType.MEMORY && cv in 1.0..4.0) {
+                                // replace by several DECs if it's not a memory address (dec on a memory mapped register doesn't work very well)
                                 val decs = AnonymousScope(mutableListOf(), assignment.position)
                                 repeat(cv.toInt()) {
                                     decs.statements.add(PostIncrDecr(assignment.target, "--", assignment.position))
@@ -386,28 +438,10 @@ internal class StatementOptimizer(private val program: Program,
                     "<<" -> {
                         if (cv == 0.0)
                             return listOf(IAstModification.Remove(assignment, parent))
-                        // replace by in-place lsl(...) call
-                        val scope = AnonymousScope(mutableListOf(), assignment.position)
-                        var numshifts = cv.toInt()
-                        while (numshifts > 0) {
-                            scope.statements.add(FunctionCallStatement(IdentifierReference(listOf("lsl"), assignment.position),
-                                    mutableListOf(bexpr.left), true, assignment.position))
-                            numshifts--
-                        }
-                        return listOf(IAstModification.ReplaceNode(assignment, scope, parent))
                     }
                     ">>" -> {
                         if (cv == 0.0)
                             return listOf(IAstModification.Remove(assignment, parent))
-                        // replace by in-place lsr(...) call
-                        val scope = AnonymousScope(mutableListOf(), assignment.position)
-                        var numshifts = cv.toInt()
-                        while (numshifts > 0) {
-                            scope.statements.add(FunctionCallStatement(IdentifierReference(listOf("lsr"), assignment.position),
-                                    mutableListOf(bexpr.left), true, assignment.position))
-                            numshifts--
-                        }
-                        return listOf(IAstModification.ReplaceNode(assignment, scope, parent))
                     }
                 }
 
@@ -441,7 +475,7 @@ internal class StatementOptimizer(private val program: Program,
         return linesToRemove
     }
 
-    private fun hasContinueOrBreak(scope: INameScope): Boolean {
+    private fun hasBreak(scope: INameScope): Boolean {
 
         class Searcher: IAstVisitor
         {
@@ -450,10 +484,6 @@ internal class StatementOptimizer(private val program: Program,
             override fun visit(breakStmt: Break) {
                 count++
             }
-
-            override fun visit(contStmt: Continue) {
-                count++
-            }
         }
 
         val s=Searcher()

compiler/src/prog8/optimizer/UnusedCodeRemover.kt

@@ -1,13 +1,14 @@
 package prog8.optimizer
 
+import prog8.ast.INameScope
 import prog8.ast.Node
 import prog8.ast.Program
+import prog8.ast.base.ErrorReporter
 import prog8.ast.processing.AstWalker
 import prog8.ast.processing.IAstModification
-import prog8.ast.statements.Block
+import prog8.ast.statements.*
 
-
-internal class UnusedCodeRemover: AstWalker() {
+internal class UnusedCodeRemover(private val errors: ErrorReporter): AstWalker() {
 
     override fun before(program: Program, parent: Node): Iterable<IAstModification> {
         val callgraph = CallGraph(program)
@@ -17,8 +18,9 @@ internal class UnusedCodeRemover: AstWalker() {
         val entrypoint = program.entrypoint()
         program.modules.forEach {
             callgraph.forAllSubroutines(it) { sub ->
-                if (sub !== entrypoint && !sub.keepAlways && (callgraph.calledBy[sub].isNullOrEmpty() || (sub.containsNoCodeNorVars() && !sub.isAsmSubroutine)))
+                if (sub !== entrypoint && !sub.isAsmSubroutine && (callgraph.calledBy[sub].isNullOrEmpty() || sub.containsNoCodeNorVars())) {
                     removals.add(IAstModification.Remove(sub, sub.definingScope() as Node))
+                }
             }
         }
 
@@ -35,4 +37,33 @@ internal class UnusedCodeRemover: AstWalker() {
 
         return removals
     }
+
+
+    override fun before(breakStmt: Break, parent: Node): Iterable<IAstModification> {
+        reportUnreachable(breakStmt, parent as INameScope)
+        return emptyList()
+    }
+
+    override fun before(jump: Jump, parent: Node): Iterable<IAstModification> {
+        reportUnreachable(jump, parent as INameScope)
+        return emptyList()
+    }
+
+    override fun before(returnStmt: Return, parent: Node): Iterable<IAstModification> {
+        reportUnreachable(returnStmt, parent as INameScope)
+        return emptyList()
+    }
+
+    override fun before(functionCallStatement: FunctionCallStatement, parent: Node): Iterable<IAstModification> {
+        if(functionCallStatement.target.nameInSource.last() == "exit")
+            reportUnreachable(functionCallStatement, parent as INameScope)
+        return emptyList()
+    }
+
+    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 -> {}
+            else -> errors.warn("unreachable code", next.position)
+        }
+    }
 }

compiler/src/prog8/parser/ModuleParsing.kt

@@ -4,7 +4,6 @@ import org.antlr.v4.runtime.*
 import prog8.ast.Module
 import prog8.ast.Program
 import prog8.ast.antlr.toAst
-import prog8.ast.base.ErrorReporter
 import prog8.ast.base.Position
 import prog8.ast.base.SyntaxError
 import prog8.ast.base.checkImportedValid
@@ -34,7 +33,7 @@ internal class CustomLexer(val modulePath: Path, input: CharStream?) : prog8Lexe
 internal fun moduleName(fileName: Path) = fileName.toString().substringBeforeLast('.')
 
 
-internal class ModuleImporter(private val errors: ErrorReporter) {
+internal class ModuleImporter {
 
     internal fun importModule(program: Program, filePath: Path): Module {
         print("importing '${moduleName(filePath.fileName)}'")
@@ -95,7 +94,7 @@ internal class ModuleImporter(private val errors: ErrorReporter) {
 
     private fun discoverImportedModuleFile(name: String, source: Path, position: Position?): Path {
         val fileName = "$name.p8"
-        val locations = mutableListOf(source.parent)
+        val locations = if(source.toString().isEmpty()) mutableListOf<Path>() else mutableListOf(source.parent)
 
         val propPath = System.getProperty("prog8.libdir")
         if(propPath!=null)
@@ -110,7 +109,7 @@ internal class ModuleImporter(private val errors: ErrorReporter) {
             if (Files.isReadable(file)) return file
         }
 
-        throw ParsingFailedError("$position Import: no module source file '$fileName' found  (I've looked in: $locations)")
+        throw ParsingFailedError("$position Import: no module source file '$fileName' found  (I've looked in: embedded libs and $locations)")
     }
 
     private fun executeImportDirective(program: Program, import: Directive, source: Path): Module? {
@@ -129,10 +128,7 @@ internal class ModuleImporter(private val errors: ErrorReporter) {
                 if(resource!=null) {
                     // load the module from the embedded resource
                     resource.use {
-                        if(import.args[0].int==42)
-                            println("importing '$moduleName' (library, auto)")
-                        else
-                            println("importing '$moduleName' (library)")
+                        println("importing '$moduleName' (library)")
                         importModule(program, CharStreams.fromStream(it), Paths.get("@embedded@/$moduleName"), true)
                     }
                 } else {

compiler/test/UnitTests.kt

@@ -123,13 +123,13 @@ class TestCompiler {
 
 
 @TestInstance(TestInstance.Lifecycle.PER_CLASS)
-class TestZeropage {
+class TestC64Zeropage {
 
     private val errors = ErrorReporter()
 
     @Test
     fun testNames() {
-        val zp = C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.BASICSAFE, emptyList(), false))
+        val zp = C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.BASICSAFE, emptyList(), false, "c64"))
 
         zp.allocate("", DataType.UBYTE, null, errors)
         zp.allocate("", DataType.UBYTE, null, errors)
@@ -142,37 +142,37 @@ class TestZeropage {
 
     @Test
     fun testZpFloatEnable() {
-        val zp = C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.FULL, emptyList(), false))
+        val zp = C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.FULL, emptyList(), false, "c64"))
         assertFailsWith<CompilerException> {
             zp.allocate("", DataType.FLOAT, null, errors)
         }
-        val zp2 = C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.DONTUSE, emptyList(), true))
+        val zp2 = C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.DONTUSE, emptyList(), true, "c64"))
         assertFailsWith<CompilerException> {
             zp2.allocate("", DataType.FLOAT, null, errors)
         }
-        val zp3 = C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.FLOATSAFE, emptyList(), true))
+        val zp3 = C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.FLOATSAFE, emptyList(), true, "c64"))
         zp3.allocate("", DataType.FLOAT, null, errors)
     }
 
     @Test
     fun testZpModesWithFloats() {
-        C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.FULL, emptyList(), false))
-        C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.KERNALSAFE, emptyList(), false))
-        C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.BASICSAFE, emptyList(), false))
-        C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.FLOATSAFE, emptyList(), false))
-        C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.BASICSAFE, emptyList(), true))
-        C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.FLOATSAFE, emptyList(), true))
+        C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.FULL, emptyList(), false, "c64"))
+        C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.KERNALSAFE, emptyList(), false, "c64"))
+        C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.BASICSAFE, emptyList(), false, "c64"))
+        C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.FLOATSAFE, emptyList(), false, "c64"))
+        C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.BASICSAFE, emptyList(), true, "c64"))
+        C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.FLOATSAFE, emptyList(), true, "c64"))
         assertFailsWith<CompilerException> {
-            C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.FULL, emptyList(), true))
+            C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.FULL, emptyList(), true, "c64"))
         }
         assertFailsWith<CompilerException> {
-            C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.KERNALSAFE, emptyList(), true))
+            C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.KERNALSAFE, emptyList(), true, "c64"))
         }
     }
 
     @Test
     fun testZpDontuse() {
-        val zp = C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.DONTUSE, emptyList(), false))
+        val zp = C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.DONTUSE, emptyList(), false, "c64"))
         println(zp.free)
         assertEquals(0, zp.available())
         assertFailsWith<CompilerException> {
@@ -182,19 +182,19 @@ class TestZeropage {
 
     @Test
     fun testFreeSpaces() {
-        val zp1 = C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.BASICSAFE, emptyList(), true))
+        val zp1 = C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.BASICSAFE, emptyList(), true, "c64"))
         assertEquals(16, zp1.available())
-        val zp2 = C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.FLOATSAFE, emptyList(), false))
+        val zp2 = C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.FLOATSAFE, emptyList(), false, "c64"))
         assertEquals(91, zp2.available())
-        val zp3 = C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.KERNALSAFE, emptyList(), false))
+        val zp3 = C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.KERNALSAFE, emptyList(), false, "c64"))
         assertEquals(125, zp3.available())
-        val zp4 = C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.FULL, emptyList(), false))
+        val zp4 = C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.FULL, emptyList(), false, "c64"))
         assertEquals(238, zp4.available())
     }
 
     @Test
     fun testReservedSpace() {
-        val zp1 = C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.FULL, emptyList(), false))
+        val zp1 = C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.FULL, emptyList(), false, "c64"))
         assertEquals(238, zp1.available())
         assertTrue(50 in zp1.free)
         assertTrue(100 in zp1.free)
@@ -203,7 +203,7 @@ class TestZeropage {
         assertTrue(200 in zp1.free)
         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))
+        val zp2 = C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.FULL, listOf(50 .. 100, 200..255), false, "c64"))
         assertEquals(139, zp2.available())
         assertFalse(50 in zp2.free)
         assertFalse(100 in zp2.free)
@@ -216,7 +216,7 @@ class TestZeropage {
 
     @Test
     fun testBasicsafeAllocation() {
-        val zp = C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.BASICSAFE, emptyList(), true))
+        val zp = C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.BASICSAFE, emptyList(), true, "c64"))
         assertEquals(16, zp.available())
 
         assertFailsWith<ZeropageDepletedError> {
@@ -239,7 +239,7 @@ class TestZeropage {
 
     @Test
     fun testFullAllocation() {
-        val zp = C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.FULL, emptyList(), false))
+        val zp = C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.FULL, emptyList(), false, "c64"))
         assertEquals(238, zp.available())
         val loc = zp.allocate("", DataType.UWORD, null, errors)
         assertTrue(loc > 3)
@@ -269,7 +269,7 @@ class TestZeropage {
 
     @Test
     fun testEfficientAllocation() {
-        val zp = C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.BASICSAFE, emptyList(),  true))
+        val zp = C64Zeropage(CompilationOptions(OutputType.RAW, LauncherType.NONE, ZeropageType.BASICSAFE, emptyList(),  true, "c64"))
         assertEquals(16, zp.available())
         assertEquals(0x04, zp.allocate("", DataType.WORD, null, errors))
         assertEquals(0x06, zp.allocate("", DataType.UBYTE, null, errors))

docs/source/building.rst

@@ -83,7 +83,7 @@ For normal use the compiler is invoked with the command:
 By default, assembly code is generated and written to ``sourcefile.asm``.
 It is then (automatically) fed to the `64tass <https://sourceforge.net/projects/tass64/>`_ cross assembler tool
 that assembles it into the final program.
-If you use the option to let the compiler auto-start a C-64 emulator, it will do so after
+If you use the option to let the compiler auto-start an emulator, it will do so after
 a successful compilation. This will load your program and the symbol and breakpoint lists
 (for the machine code monitor) into the emulator.
 
@@ -109,8 +109,8 @@ A module source file is a text file with the ``.p8`` suffix, containing the prog
 It consists of compilation options and other directives, imports of other modules,
 and source code for one or more code blocks.
 
-Prog8 has a couple of *LIBRARY* modules that are defined in special internal files provided by the compiler:
-``c64lib``, ``c64utils``, ``c64flt`` and ``prog8lib``. You should not overwrite these or reuse their names.
+Prog8 has various *LIBRARY* modules that are defined in special internal files provided by the compiler.
+You should not overwrite these or reuse their names.
 They are embedded into the packaged release version of the compiler so you don't have to worry about
 where they are, but their names are still reserved.
 

docs/source/index.rst

@@ -12,6 +12,7 @@ What is Prog8?
 
 This is an experimental compiled programming language targeting the 8-bit
 `6502 <https://en.wikipedia.org/wiki/MOS_Technology_6502>`_ /
+`65c02 <https://en.wikipedia.org/wiki/MOS_Technology_65C02>`_ /
 `6510 <https://en.wikipedia.org/wiki/MOS_Technology_6510>`_ microprocessor.
 This CPU is from the late 1970's and early 1980's and was used in many home computers from that era,
 such as the `Commodore-64 <https://en.wikipedia.org/wiki/Commodore_64>`_.
@@ -42,7 +43,7 @@ Code examples
 
 This code calculates prime numbers using the Sieve of Eratosthenes algorithm::
 
-    %import c64utils
+    %import c64textio
     %zeropage basicsafe
 
     main {
@@ -51,35 +52,33 @@ This code calculates prime numbers using the Sieve of Eratosthenes algorithm::
         ubyte candidate_prime = 2
 
         sub start() {
-            memset(sieve, 256, false)
-
-            c64scr.print("prime numbers up to 255:\n\n")
+            memset(sieve, 256, false)   ; clear the sieve
+            txt.print("prime numbers up to 255:\n\n")
             ubyte amount=0
-            while true {
+            repeat {
                 ubyte prime = find_next_prime()
                 if prime==0
                     break
-                c64scr.print_ub(prime)
-                c64scr.print(", ")
+                txt.print_ub(prime)
+                txt.print(", ")
                 amount++
             }
             c64.CHROUT('\n')
-            c64scr.print("number of primes (expected 54): ")
-            c64scr.print_ub(amount)
+            txt.print("number of primes (expected 54): ")
+            txt.print_ub(amount)
             c64.CHROUT('\n')
         }
 
-
         sub find_next_prime() -> ubyte {
-
             while sieve[candidate_prime] {
                 candidate_prime++
                 if candidate_prime==0
-                    return 0
+                    return 0        ; we wrapped; no more primes available
             }
-
+            ; found next one, mark the multiples and return it.
             sieve[candidate_prime] = true
             uword multiple = candidate_prime
+
             while multiple < len(sieve) {
                 sieve[lsb(multiple)] = true
                 multiple += candidate_prime
@@ -89,6 +88,7 @@ This code calculates prime numbers using the Sieve of Eratosthenes algorithm::
     }
 
 
+
 when compiled an ran on a C-64 you get this:
 
 .. image:: _static/primes_example.png
@@ -98,7 +98,8 @@ when compiled an ran on a C-64 you get this:
 
 The following programs shows a use of the high level ``struct`` type::
 
-    %import c64utils
+
+    %import c64textio
     %zeropage basicsafe
 
     main {
@@ -111,22 +112,25 @@ The following programs shows a use of the high level ``struct`` type::
 
         sub start() {
 
-            Color purple = {255, 0, 255}
+            Color purple = [255, 0, 255]
+
             Color other
+
             other = purple
             other.red /= 2
             other.green = 10 + other.green / 2
             other.blue = 99
 
-            c64scr.print_ub(other.red)
+            txt.print_ub(other.red)
             c64.CHROUT(',')
-            c64scr.print_ub(other.green)
+            txt.print_ub(other.green)
             c64.CHROUT(',')
-            c64scr.print_ub(other.blue)
+            txt.print_ub(other.blue)
             c64.CHROUT('\n')
         }
     }
 
+
 when compiled and ran, it prints  ``127,10,99`` on the screen.
 
 
@@ -175,6 +179,7 @@ Fnd for Windows it's possible to get that as well. Check out `AdoptOpenJDK <http
 
 Finally: a **C-64 emulator** (or a real C-64 ofcourse) can be nice to test and run your programs on.
 The compiler assumes the presence of the `Vice emulator <http://vice-emu.sourceforge.net/>`_.
+If you're targeting the CommanderX16, there's the `x16emu <https://github.com/commanderx16/x16-emulator>`_.
 
 .. important::
     **Building the compiler itself:** (*Only needed if you have not downloaded a pre-built 'fat-jar'*)

docs/source/programming.rst

@@ -257,6 +257,16 @@ Note that the various keywords for the data type and variable type (``byte``, ``
 can't be used as *identifiers* elsewhere. You can't make a variable, block or subroutine with the name ``byte``
 for instance.
 
+**Arrays at a specific memory location:**
+Using the memory-mapped syntax it is possible to define an array to be located at a specific memory location.
+For instance to reference the first 5 rows of the Commodore 64's screen matrix as an array, you can define::
+
+    &ubyte[5*40]  top5screenrows = $0400
+
+This way you can set the second character on the second row from the top like this::
+
+    top5screenrows[41] = '!'
+
 
 Strings
 ^^^^^^^
@@ -397,6 +407,8 @@ The *repeat* loop is used as a short notation of a for loop where the loop varia
 
 You can also create loops by using the ``goto`` statement, but this should usually be avoided.
 
+Breaking out of a loop prematurely is possible with the ``break`` statement.
+
 .. attention::
     The value of the loop variable after executing the loop *is undefined*. Don't use it immediately
     after the loop without first assigning a new value to it!
@@ -712,11 +724,17 @@ reverse(array)
 
 len(x)
     Number of values in the array value x, or the number of characters in a string (excluding the size or 0-byte).
-    Note: this can be different from the number of *bytes* in memory if the datatype isn't a 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)
 
+sizeof(name)
+    Number of bytes that the object 'name' occupies in memory. This is a constant determined by the data type of
+    the object. For instance, for a variable of type uword, the sizeof is 2.
+    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.
+
 strlen(str)
     Number of bytes in the string. This value is determined during runtime and counts upto
     the first terminating 0 byte in the string, regardless of the size of the string during compilation time.
@@ -730,8 +748,9 @@ msb(x)
 sgn(x)
     Get the sign of the value. Result is -1, 0 or 1 (negative, zero, positive).
 
-mkword(lsb, msb)
-    Efficiently create a word value from two bytes (the lsb and the msb). Avoids multiplication and shifting.
+mkword(msb, lsb)
+    Efficiently create a word value from two bytes (the msb and the lsb). Avoids multiplication and shifting.
+    So mkword($80, $22) results in $8022.
 
 any(x)
     1 ('true') if any of the values in the array value x is 'true' (not zero), else 0 ('false')
@@ -748,16 +767,6 @@ rndw()
 rndf()
     returns a pseudo-random float between 0.0 and 1.0
 
-lsl(x)
-    Shift the bits in x (byte or word) one position to the left.
-    Bit 0 is set to 0 (and the highest bit is shifted into the status register's Carry flag)
-    Modifies in-place, doesn't return a value (so can't be used in an expression).
-
-lsr(x)
-    Shift the bits in x (byte or word) one position to the right.
-    The highest bit is set to 0 (and bit 0 is shifted into the status register's Carry flag)
-    Modifies in-place, doesn't return a value (so can't be used in an expression).
-
 rol(x)
     Rotate the bits in x (byte or word) one position to the left.
     This uses the CPU's rotate semantics: bit 0 will be set to the current value of the Carry flag,
@@ -794,7 +803,7 @@ memset(address, numbytes, bytevalue)
     Efficiently set a part of memory to the given (u)byte value.
     But the most efficient will always be to write a specialized fill routine in assembly yourself!
     Note that for clearing the character screen, very fast specialized subroutines are
-    available in the ``c64scr`` block (part of the ``c64utils`` module)
+    available in the ``screen`` block (part of the ``c64textio`` or ``cx16textio`` modules)
 
 memsetw(address, numwords, wordvalue)
     Efficiently set a part of memory to the given (u)word value.

docs/source/syntaxreference.rst

@@ -33,6 +33,14 @@ This makes it easier to understand and relate the generated code. Examples::
 Directives
 -----------
 
+.. data:: %target <target>
+
+    Level: module.
+    Global setting, selects a compilation target from within the source file.
+    The default compilation target is "c64" which targets the Commodore-64 machine.
+    You can also omit this and use the ``-target`` command line option.
+
+
 .. data:: %output <type>
 
 	Level: module.
@@ -157,7 +165,7 @@ Directives
 Identifiers
 -----------
 
-Naming things in Prog8 is done via valid *identifiers*. They start with a letter or underscore,
+Naming things in Prog8 is done via valid *identifiers*. They start with a letter,
 and after that, a combination of letters, numbers, or underscores. Examples of valid identifiers::
 
 	a
@@ -165,7 +173,7 @@ and after that, a combination of letters, numbers, or underscores. Examples of v
 	monkey
 	COUNTER
 	Better_Name_2
-	_something_strange_
+	something_strange__
 
 
 Code blocks
@@ -306,6 +314,7 @@ should be allocated by the compiler. Instead, the (mandatory) value assigned to
 should be the *memory address* where the value is located::
 
 	&byte BORDERCOLOR = $d020
+    &ubyte[5*40]  top5screenrows = $0400        ; works for array as well
 
 
 Direct access to memory locations
@@ -404,7 +413,7 @@ assignment: ``=``
     Note that an assignment sometimes is not possible or supported.
 
 augmented assignment: ``+=``  ``-=``  ``*=``  ``/=``  ``**=``  ``&=``  ``|=``  ``^=``  ``<<=``  ``>>=``
-	Syntactic sugar; ``aa += xx`` is equivalent to ``aa = aa + xx``
+	This is syntactic sugar; ``aa += xx`` is equivalent to ``aa = aa + xx``
 
 postfix increment and decrement: ``++``  ``--``
 	Syntactic sugar; ``aa++`` is equivalent to ``aa = aa + 1``, and ``aa--`` is equivalent to ``aa = aa - 1``.
@@ -513,18 +522,20 @@ and returning stuff in several registers as well. The ``clobbers`` clause is use
 what CPU registers are clobbered by the call instead of being unchanged or returning a meaningful result value.
 
 
-Subroutines that are implemented purely in assembly code and which have an assembly calling convention (i.e.
-the parameters are strictly passed via cpu registers), are defined like this::
+User subroutines in the program source code that are implemented purely in assembly and which have an assembly calling convention (i.e.
+the parameters are strictly passed via cpu registers), are defined with ``asmsub`` like this::
 
-    asmsub  FREADS32() clobbers(A,X,Y)  {
+    asmsub  clear_screenchars (ubyte char @ A) clobbers(Y)  {
         %asm {{
-            lda  $62
-            eor  #$ff
-            asl  a
-            lda  #0
-            ldx  #$a0
-            jmp  $bc4f
-        }}
+            ldy  #0
+    _loop   sta  c64.Screen,y
+            sta  c64.Screen+$0100,y
+            sta  c64.Screen+$0200,y
+            sta  c64.Screen+$02e8,y
+            iny
+            bne  _loop
+            rts
+            }}
     }
 
 the statement body of such a subroutine should consist of just an inline assembly block.
@@ -559,7 +570,6 @@ You can use a single statement, or a statement block like in the example below::
 	for <loopvar>  in  <expression>  [ step <amount> ]   {
 		; do something...
 		break		; break out of the loop
-		continue	; immediately enter next iteration
 	}
 
 For example, this is a for loop using a byte variable ``i``, defined before, to loop over a certain range of numbers::
@@ -592,7 +602,6 @@ You can use a single statement, or a statement block like in the example below::
 	while  <condition>  {
 		; do something...
 		break		; break out of the loop
-		continue	; immediately enter next iteration
 	}
 
 
@@ -605,7 +614,6 @@ You can use a single statement, or a statement block like in the example below::
 	do  {
 		; do something...
 		break		; break out of the loop
-		continue	; immediately enter next iteration
 	} until  <condition>
 
 

docs/source/targetsystem.rst

@@ -4,12 +4,17 @@ Target system specification
 
 Prog8 targets the following hardware:
 
-- 8 bit MOS 6502/6510 CPU
+- 8 bit MOS 6502/65c02/6510 CPU
 - 64 Kb addressable memory (RAM or ROM)
-- memory mapped I/O registers
+- optional use of memory mapped I/O registers
+- optional use of system ROM routines
 
-The main target machine is the Commodore-64, which is an example of this.
-This chapter explains the relevant system details of such a machine.
+Currently there are two machines that are supported as compiler target (via the ``-target`` compiler argument):
+
+- 'c64': the well-known Commodore-64, premium support
+- 'cx16': the `CommanderX16 <https://www.commanderx16.com/>`_ a project from the 8-Bit Guy. Support for this is still experimental.
+
+This chapter explains the relevant system details of these machines.
 
 
 Memory Model
@@ -147,15 +152,15 @@ You can however install your own IRQ handler.
 This is possible ofcourse by doing it all using customized inline assembly,
 but there are a few library routines available to make setting up C-64 IRQs and raster IRQs a lot easier (no assembly code required).
 
-These routines are::
+For the C64 these routines are::
 
-    c64utils.set_irqvec()
-    c64utils.set_irqvec_excl()
+    c64.set_irqvec()
+    c64.set_irqvec_excl()
 
-    c64utils.set_rasterirq( <raster line> )
-    c64utils.set_rasterirq_excl( <raster line> )
+    c64.set_rasterirq( <raster line> )
+    c64.set_rasterirq_excl( <raster line> )
 
-    c64utils.restore_irqvec()     ; set it back to the systems default irq handler
+    c64.restore_irqvec()     ; set it back to the systems default irq handler
 
 If you activate an IRQ handler with one of these, it expects the handler to be defined
 as a subroutine ``irq`` in the module ``irq`` so like this::

docs/source/todo.rst

@@ -2,10 +2,15 @@
 TODO
 ====
 
-- finalize (most) of the still missing "new" assignment asm code generation
-- aliases for imported symbols for example perhaps '%alias print = c64scr.print'
-- option to load library files from a directory instead of the embedded ones (easier library development/debugging)
-- investigate support for 8bitguy's Commander X16 platform https://www.commanderx16.com  and https://github.com/commanderx16/x16-docs
+- get rid of all other TODO's in the code ;-)
+- line-circle-gfx examples are now a few hundred bytes larger than before. Why is that, can it be fixed?
+- compiler errors and warnings in standard format so the IDE shows them as clickable links; ./test.asm:2578:3: blablabla
+- further optimize assignment codegeneration
+- auto select correct library to import based on target, instead of having c64- and  cx16-  prefix variants
+- implement @stack for asmsub parameters
+- make it possible to use cpu opcodes such as 'nop' as variable names by prefixing all asm vars with something such as '_'
+- option to load the built-in library files from a directory instead of the embedded ones (for easier library development/debugging)
+- aliases for imported symbols for example perhaps '%alias print = c64scr.print' ?
 - see if we can group some errors together for instance the (now single) errors about unidentified symbols
 
 

examples/arithmetic/aggregates.p8

@@ -1,7 +1,6 @@
-%import c64lib
-%import c64utils
 %import c64flt
-%zeropage dontuse
+%import c64textio
+%zeropage basicsafe
 
 main {
 
@@ -20,90 +19,90 @@ main {
 
         ; LEN/STRLEN
         ubyte length = len(name)
-        if length!=5 c64scr.print("error len1\n")
+        if length!=5 txt.print("error len1\n")
         length = len(uwarr)
-        if length!=5 c64scr.print("error len2\n")
+        if length!=5 txt.print("error len2\n")
         length=strlen(name)
-        if length!=5 c64scr.print("error strlen1\n")
+        if length!=5 txt.print("error strlen1\n")
         name[3] = 0
         length=strlen(name)
-        if length!=3 c64scr.print("error strlen2\n")
+        if length!=3 txt.print("error strlen2\n")
 
         ; MAX
         ub = max(ubarr)
-        if ub!=199 c64scr.print("error max1\n")
+        if ub!=199 txt.print("error max1\n")
         bb = max(barr)
-        if bb!=99 c64scr.print("error max2\n")
+        if bb!=99 txt.print("error max2\n")
         uw = max(uwarr)
-        if uw!=4444 c64scr.print("error max3\n")
+        if uw!=4444 txt.print("error max3\n")
         ww = max(warr)
-        if ww!=999 c64scr.print("error max4\n")
+        if ww!=999 txt.print("error max4\n")
         ff = max(farr)
-        if ff!=999.9 c64scr.print("error max5\n")
+        if ff!=999.9 txt.print("error max5\n")
 
         ; MIN
         ub = min(ubarr)
-        if ub!=0 c64scr.print("error min1\n")
+        if ub!=0 txt.print("error min1\n")
         bb = min(barr)
-        if bb!=-122 c64scr.print("error min2\n")
+        if bb!=-122 txt.print("error min2\n")
         uw = min(uwarr)
-        if uw!=0 c64scr.print("error min3\n")
+        if uw!=0 txt.print("error min3\n")
         ww = min(warr)
-        if ww!=-4444 c64scr.print("error min4\n")
+        if ww!=-4444 txt.print("error min4\n")
         ff = min(farr)
-        if ff!=-4444.4 c64scr.print("error min5\n")
+        if ff!=-4444.4 txt.print("error min5\n")
 
         ; SUM
         uw = sum(ubarr)
-        if uw!=420 c64scr.print("error sum1\n")
+        if uw!=420 txt.print("error sum1\n")
         ww = sum(barr)
-        if ww!=-101 c64scr.print("error sum2\n")
+        if ww!=-101 txt.print("error sum2\n")
         uw = sum(uwarr)
-        if uw!=6665 c64scr.print("error sum3\n")
+        if uw!=6665 txt.print("error sum3\n")
         ww = sum(warr)
-        if ww!=-4223 c64scr.print("error sum4\n")
+        if ww!=-4223 txt.print("error sum4\n")
         ff = sum(farr)
-        if ff!=-4222.4 c64scr.print("error sum5\n")
+        if ff!=-4222.4 txt.print("error sum5\n")
 
         ; ANY
         ub = any(ubarr)
-        if ub==0 c64scr.print("error any1\n")
+        if ub==0 txt.print("error any1\n")
         ub = any(barr)
-        if ub==0 c64scr.print("error any2\n")
+        if ub==0 txt.print("error any2\n")
         ub = any(uwarr)
-        if ub==0 c64scr.print("error any3\n")
+        if ub==0 txt.print("error any3\n")
         ub = any(warr)
-        if ub==0 c64scr.print("error any4\n")
+        if ub==0 txt.print("error any4\n")
         ub = any(farr)
-        if ub==0 c64scr.print("error any5\n")
+        if ub==0 txt.print("error any5\n")
 
         ; ALL
         ub = all(ubarr)
-        if ub==1 c64scr.print("error all1\n")
+        if ub==1 txt.print("error all1\n")
         ub = all(barr)
-        if ub==1 c64scr.print("error all2\n")
+        if ub==1 txt.print("error all2\n")
         ub = all(uwarr)
-        if ub==1 c64scr.print("error all3\n")
+        if ub==1 txt.print("error all3\n")
         ub = all(warr)
-        if ub==1 c64scr.print("error all4\n")
+        if ub==1 txt.print("error all4\n")
         ub = all(farr)
-        if ub==1 c64scr.print("error all5\n")
+        if ub==1 txt.print("error all5\n")
         ubarr[1]=$40
         barr[1]=$40
         uwarr[1]=$4000
         warr[1]=$4000
         farr[1]=1.1
         ub = all(ubarr)
-        if ub==0 c64scr.print("error all6\n")
+        if ub==0 txt.print("error all6\n")
         ub = all(barr)
-        if ub==0 c64scr.print("error all7\n")
+        if ub==0 txt.print("error all7\n")
         ub = all(uwarr)
-        if ub==0 c64scr.print("error all8\n")
+        if ub==0 txt.print("error all8\n")
         ub = all(warr)
-        if ub==0 c64scr.print("error all9\n")
+        if ub==0 txt.print("error all9\n")
         ub = all(farr)
-        if ub==0 c64scr.print("error all10\n")
+        if ub==0 txt.print("error all10\n")
 
-        c64scr.print("\nyou should see no errors printed above (only at first run).")
+        txt.print("\nyou should see no errors printed above (only at first run).")
     }
 }

examples/arithmetic/bitshift.p8

@@ -1,5 +1,5 @@
-%import c64utils
-%zeropage dontuse
+%import c64textio
+%zeropage basicsafe
 
 
 main {
@@ -7,379 +7,379 @@ main {
     sub start() {
         ubyte A
 
-        c64scr.print("ubyte shift left\n")
+        txt.print("ubyte shift left\n")
         A = shiftlb0()
-        c64scr.print_ubbin(A, true)
+        txt.print_ubbin(A, true)
         c64.CHROUT('\n')
         A = shiftlb1()
-        c64scr.print_ubbin(A, true)
+        txt.print_ubbin(A, true)
         c64.CHROUT('\n')
         A = shiftlb2()
-        c64scr.print_ubbin(A, true)
+        txt.print_ubbin(A, true)
         c64.CHROUT('\n')
         A = shiftlb3()
-        c64scr.print_ubbin(A, true)
+        txt.print_ubbin(A, true)
         c64.CHROUT('\n')
         A = shiftlb4()
-        c64scr.print_ubbin(A, true)
+        txt.print_ubbin(A, true)
         c64.CHROUT('\n')
         A = shiftlb5()
-        c64scr.print_ubbin(A, true)
+        txt.print_ubbin(A, true)
         c64.CHROUT('\n')
         A = shiftlb6()
-        c64scr.print_ubbin(A, true)
+        txt.print_ubbin(A, true)
         c64.CHROUT('\n')
         A = shiftlb7()
-        c64scr.print_ubbin(A, true)
+        txt.print_ubbin(A, true)
         c64.CHROUT('\n')
         A = shiftlb8()
-        c64scr.print_ubbin(A, true)
+        txt.print_ubbin(A, true)
         c64.CHROUT('\n')
         A = shiftlb9()
-        c64scr.print_ubbin(A, true)
+        txt.print_ubbin(A, true)
         c64.CHROUT('\n')
-        c64scr.print("enter to continue:\n")
+        txt.print("enter to continue:\n")
         void c64.CHRIN()
 
-        c64scr.print("ubyte shift right\n")
+        txt.print("ubyte shift right\n")
         A = shiftrb0()
-        c64scr.print_ubbin(A, true)
+        txt.print_ubbin(A, true)
         c64.CHROUT('\n')
         A = shiftrb1()
-        c64scr.print_ubbin(A, true)
+        txt.print_ubbin(A, true)
         c64.CHROUT('\n')
         A = shiftrb2()
-        c64scr.print_ubbin(A, true)
+        txt.print_ubbin(A, true)
         c64.CHROUT('\n')
         A = shiftrb3()
-        c64scr.print_ubbin(A, true)
+        txt.print_ubbin(A, true)
         c64.CHROUT('\n')
         A = shiftrb4()
-        c64scr.print_ubbin(A, true)
+        txt.print_ubbin(A, true)
         c64.CHROUT('\n')
         A = shiftrb5()
-        c64scr.print_ubbin(A, true)
+        txt.print_ubbin(A, true)
         c64.CHROUT('\n')
         A = shiftrb6()
-        c64scr.print_ubbin(A, true)
+        txt.print_ubbin(A, true)
         c64.CHROUT('\n')
         A = shiftrb7()
-        c64scr.print_ubbin(A, true)
+        txt.print_ubbin(A, true)
         c64.CHROUT('\n')
         A = shiftrb8()
-        c64scr.print_ubbin(A, true)
+        txt.print_ubbin(A, true)
         c64.CHROUT('\n')
         A = shiftrb9()
-        c64scr.print_ubbin(A, true)
+        txt.print_ubbin(A, true)
         c64.CHROUT('\n')
-        c64scr.print("enter to continue:\n")
+        txt.print("enter to continue:\n")
         void c64.CHRIN()
 
 
 
 
-        c64scr.print("signed byte shift left\n")
+        txt.print("signed byte shift left\n")
         byte signedb
         signedb = shiftlsb0()
-        c64scr.print_ubbin(signedb as ubyte, true)
+        txt.print_ubbin(signedb as ubyte, true)
         c64.CHROUT('\n')
         signedb = shiftlsb1()
-        c64scr.print_ubbin(signedb as ubyte, true)
+        txt.print_ubbin(signedb as ubyte, true)
         c64.CHROUT('\n')
         signedb = shiftlsb2()
-        c64scr.print_ubbin(signedb as ubyte, true)
+        txt.print_ubbin(signedb as ubyte, true)
         c64.CHROUT('\n')
         signedb = shiftlsb3()
-        c64scr.print_ubbin(signedb as ubyte, true)
+        txt.print_ubbin(signedb as ubyte, true)
         c64.CHROUT('\n')
         signedb = shiftlsb4()
-        c64scr.print_ubbin(signedb as ubyte, true)
+        txt.print_ubbin(signedb as ubyte, true)
         c64.CHROUT('\n')
         signedb = shiftlsb5()
-        c64scr.print_ubbin(signedb as ubyte, true)
+        txt.print_ubbin(signedb as ubyte, true)
         c64.CHROUT('\n')
         signedb = shiftlsb6()
-        c64scr.print_ubbin(signedb as ubyte, true)
+        txt.print_ubbin(signedb as ubyte, true)
         c64.CHROUT('\n')
         signedb = shiftlsb7()
-        c64scr.print_ubbin(signedb as ubyte, true)
+        txt.print_ubbin(signedb as ubyte, true)
         c64.CHROUT('\n')
         signedb = shiftlsb8()
-        c64scr.print_ubbin(signedb as ubyte, true)
+        txt.print_ubbin(signedb as ubyte, true)
         c64.CHROUT('\n')
         signedb = shiftlsb9()
-        c64scr.print_ubbin(signedb as ubyte, true)
+        txt.print_ubbin(signedb as ubyte, true)
         c64.CHROUT('\n')
-        c64scr.print("enter to continue:\n")
+        txt.print("enter to continue:\n")
         void c64.CHRIN()
 
-        c64scr.print("signed byte shift right\n")
+        txt.print("signed byte shift right\n")
         signedb = shiftrsb0()
-        c64scr.print_ubbin(signedb as ubyte, true)
+        txt.print_ubbin(signedb as ubyte, true)
         c64.CHROUT('\n')
         signedb = shiftrsb1()
-        c64scr.print_ubbin(signedb as ubyte, true)
+        txt.print_ubbin(signedb as ubyte, true)
         c64.CHROUT('\n')
         signedb = shiftrsb2()
-        c64scr.print_ubbin(signedb as ubyte, true)
+        txt.print_ubbin(signedb as ubyte, true)
         c64.CHROUT('\n')
         signedb = shiftrsb3()
-        c64scr.print_ubbin(signedb as ubyte, true)
+        txt.print_ubbin(signedb as ubyte, true)
         c64.CHROUT('\n')
         signedb = shiftrsb4()
-        c64scr.print_ubbin(signedb as ubyte, true)
+        txt.print_ubbin(signedb as ubyte, true)
         c64.CHROUT('\n')
         signedb = shiftrsb5()
-        c64scr.print_ubbin(signedb as ubyte, true)
+        txt.print_ubbin(signedb as ubyte, true)
         c64.CHROUT('\n')
         signedb = shiftrsb6()
-        c64scr.print_ubbin(signedb as ubyte, true)
+        txt.print_ubbin(signedb as ubyte, true)
         c64.CHROUT('\n')
         signedb = shiftrsb7()
-        c64scr.print_ubbin(signedb as ubyte, true)
+        txt.print_ubbin(signedb as ubyte, true)
         c64.CHROUT('\n')
         signedb = shiftrsb8()
-        c64scr.print_ubbin(signedb as ubyte, true)
+        txt.print_ubbin(signedb as ubyte, true)
         c64.CHROUT('\n')
         signedb = shiftrsb9()
-        c64scr.print_ubbin(signedb as ubyte, true)
+        txt.print_ubbin(signedb as ubyte, true)
         c64.CHROUT('\n')
-        c64scr.print("enter to continue:\n")
+        txt.print("enter to continue:\n")
         void c64.CHRIN()
 
 
 
 
-        c64scr.print("uword shift left\n")
+        txt.print("uword shift left\n")
         uword uw
         uw = shiftluw0()
-        c64scr.print_uwbin(uw, true)
+        txt.print_uwbin(uw, true)
         c64.CHROUT('\n')
         uw = shiftluw1()
-        c64scr.print_uwbin(uw, true)
+        txt.print_uwbin(uw, true)
         c64.CHROUT('\n')
         uw = shiftluw2()
-        c64scr.print_uwbin(uw, true)
+        txt.print_uwbin(uw, true)
         c64.CHROUT('\n')
         uw = shiftluw3()
-        c64scr.print_uwbin(uw, true)
+        txt.print_uwbin(uw, true)
         c64.CHROUT('\n')
         uw = shiftluw4()
-        c64scr.print_uwbin(uw, true)
+        txt.print_uwbin(uw, true)
         c64.CHROUT('\n')
         uw = shiftluw5()
-        c64scr.print_uwbin(uw, true)
+        txt.print_uwbin(uw, true)
         c64.CHROUT('\n')
         uw = shiftluw6()
-        c64scr.print_uwbin(uw, true)
+        txt.print_uwbin(uw, true)
         c64.CHROUT('\n')
         uw = shiftluw7()
-        c64scr.print_uwbin(uw, true)
+        txt.print_uwbin(uw, true)
         c64.CHROUT('\n')
         uw = shiftluw8()
-        c64scr.print_uwbin(uw, true)
+        txt.print_uwbin(uw, true)
         c64.CHROUT('\n')
         uw = shiftluw9()
-        c64scr.print_uwbin(uw, true)
+        txt.print_uwbin(uw, true)
         c64.CHROUT('\n')
         uw = shiftluw10()
-        c64scr.print_uwbin(uw, true)
+        txt.print_uwbin(uw, true)
         c64.CHROUT('\n')
         uw = shiftluw11()
-        c64scr.print_uwbin(uw, true)
+        txt.print_uwbin(uw, true)
         c64.CHROUT('\n')
         uw = shiftluw12()
-        c64scr.print_uwbin(uw, true)
+        txt.print_uwbin(uw, true)
         c64.CHROUT('\n')
         uw = shiftluw13()
-        c64scr.print_uwbin(uw, true)
+        txt.print_uwbin(uw, true)
         c64.CHROUT('\n')
         uw = shiftluw14()
-        c64scr.print_uwbin(uw, true)
+        txt.print_uwbin(uw, true)
         c64.CHROUT('\n')
         uw = shiftluw15()
-        c64scr.print_uwbin(uw, true)
+        txt.print_uwbin(uw, true)
         c64.CHROUT('\n')
         uw = shiftluw16()
-        c64scr.print_uwbin(uw, true)
+        txt.print_uwbin(uw, true)
         c64.CHROUT('\n')
         uw = shiftluw17()
-        c64scr.print_uwbin(uw, true)
+        txt.print_uwbin(uw, true)
         c64.CHROUT('\n')
-        c64scr.print("enter to continue:\n")
+        txt.print("enter to continue:\n")
         void c64.CHRIN()
 
-        c64scr.print("uword shift right\n")
+        txt.print("uword shift right\n")
         uw = shiftruw0()
-        c64scr.print_uwbin(uw, true)
+        txt.print_uwbin(uw, true)
         c64.CHROUT('\n')
         uw = shiftruw1()
-        c64scr.print_uwbin(uw, true)
+        txt.print_uwbin(uw, true)
         c64.CHROUT('\n')
         uw = shiftruw2()
-        c64scr.print_uwbin(uw, true)
+        txt.print_uwbin(uw, true)
         c64.CHROUT('\n')
         uw = shiftruw3()
-        c64scr.print_uwbin(uw, true)
+        txt.print_uwbin(uw, true)
         c64.CHROUT('\n')
         uw = shiftruw4()
-        c64scr.print_uwbin(uw, true)
+        txt.print_uwbin(uw, true)
         c64.CHROUT('\n')
         uw = shiftruw5()
-        c64scr.print_uwbin(uw, true)
+        txt.print_uwbin(uw, true)
         c64.CHROUT('\n')
         uw = shiftruw6()
-        c64scr.print_uwbin(uw, true)
+        txt.print_uwbin(uw, true)
         c64.CHROUT('\n')
         uw = shiftruw7()
-        c64scr.print_uwbin(uw, true)
+        txt.print_uwbin(uw, true)
         c64.CHROUT('\n')
         uw = shiftruw8()
-        c64scr.print_uwbin(uw, true)
+        txt.print_uwbin(uw, true)
         c64.CHROUT('\n')
         uw = shiftruw9()
-        c64scr.print_uwbin(uw, true)
+        txt.print_uwbin(uw, true)
         c64.CHROUT('\n')
         uw = shiftruw10()
-        c64scr.print_uwbin(uw, true)
+        txt.print_uwbin(uw, true)
         c64.CHROUT('\n')
         uw = shiftruw11()
-        c64scr.print_uwbin(uw, true)
+        txt.print_uwbin(uw, true)
         c64.CHROUT('\n')
         uw = shiftruw12()
-        c64scr.print_uwbin(uw, true)
+        txt.print_uwbin(uw, true)
         c64.CHROUT('\n')
         uw = shiftruw13()
-        c64scr.print_uwbin(uw, true)
+        txt.print_uwbin(uw, true)
         c64.CHROUT('\n')
         uw = shiftruw14()
-        c64scr.print_uwbin(uw, true)
+        txt.print_uwbin(uw, true)
         c64.CHROUT('\n')
         uw = shiftruw15()
-        c64scr.print_uwbin(uw, true)
+        txt.print_uwbin(uw, true)
         c64.CHROUT('\n')
         uw = shiftruw16()
-        c64scr.print_uwbin(uw, true)
+        txt.print_uwbin(uw, true)
         c64.CHROUT('\n')
         uw = shiftruw17()
-        c64scr.print_uwbin(uw, true)
+        txt.print_uwbin(uw, true)
         c64.CHROUT('\n')
-        c64scr.print("enter to continue:\n")
+        txt.print("enter to continue:\n")
         void c64.CHRIN()
 
-        c64scr.print("signed word shift left\n")
+        txt.print("signed word shift left\n")
         word sw
         sw = shiftlsw0()
-        c64scr.print_uwbin(sw as uword, true)
+        txt.print_uwbin(sw as uword, true)
         c64.CHROUT('\n')
         sw = shiftlsw1()
-        c64scr.print_uwbin(sw as uword, true)
+        txt.print_uwbin(sw as uword, true)
         c64.CHROUT('\n')
         sw = shiftlsw2()
-        c64scr.print_uwbin(sw as uword, true)
+        txt.print_uwbin(sw as uword, true)
         c64.CHROUT('\n')
         sw = shiftlsw3()
-        c64scr.print_uwbin(sw as uword, true)
+        txt.print_uwbin(sw as uword, true)
         c64.CHROUT('\n')
         sw = shiftlsw4()
-        c64scr.print_uwbin(sw as uword, true)
+        txt.print_uwbin(sw as uword, true)
         c64.CHROUT('\n')
         sw = shiftlsw5()
-        c64scr.print_uwbin(sw as uword, true)
+        txt.print_uwbin(sw as uword, true)
         c64.CHROUT('\n')
         sw = shiftlsw6()
-        c64scr.print_uwbin(sw as uword, true)
+        txt.print_uwbin(sw as uword, true)
         c64.CHROUT('\n')
         sw = shiftlsw7()
-        c64scr.print_uwbin(sw as uword, true)
+        txt.print_uwbin(sw as uword, true)
         c64.CHROUT('\n')
         sw = shiftlsw8()
-        c64scr.print_uwbin(sw as uword, true)
+        txt.print_uwbin(sw as uword, true)
         c64.CHROUT('\n')
         sw = shiftlsw9()
-        c64scr.print_uwbin(sw as uword, true)
+        txt.print_uwbin(sw as uword, true)
         c64.CHROUT('\n')
         sw = shiftlsw10()
-        c64scr.print_uwbin(sw as uword, true)
+        txt.print_uwbin(sw as uword, true)
         c64.CHROUT('\n')
         sw = shiftlsw11()
-        c64scr.print_uwbin(sw as uword, true)
+        txt.print_uwbin(sw as uword, true)
         c64.CHROUT('\n')
         sw = shiftlsw12()
-        c64scr.print_uwbin(sw as uword, true)
+        txt.print_uwbin(sw as uword, true)
         c64.CHROUT('\n')
         sw = shiftlsw13()
-        c64scr.print_uwbin(sw as uword, true)
+        txt.print_uwbin(sw as uword, true)
         c64.CHROUT('\n')
         sw = shiftlsw14()
-        c64scr.print_uwbin(sw as uword, true)
+        txt.print_uwbin(sw as uword, true)
         c64.CHROUT('\n')
         sw = shiftlsw15()
-        c64scr.print_uwbin(sw as uword, true)
+        txt.print_uwbin(sw as uword, true)
         c64.CHROUT('\n')
         sw = shiftlsw16()
-        c64scr.print_uwbin(sw as uword, true)
+        txt.print_uwbin(sw as uword, true)
         c64.CHROUT('\n')
         sw = shiftlsw17()
-        c64scr.print_uwbin(sw as uword, true)
+        txt.print_uwbin(sw as uword, true)
         c64.CHROUT('\n')
-        c64scr.print("enter to continue:\n")
+        txt.print("enter to continue:\n")
         void c64.CHRIN()
 
-        c64scr.print("signed word shift right\n")
+        txt.print("signed word shift right\n")
         sw = shiftrsw0()
-        c64scr.print_uwbin(sw as uword, true)
+        txt.print_uwbin(sw as uword, true)
         c64.CHROUT('\n')
         sw = shiftrsw1()
-        c64scr.print_uwbin(sw as uword, true)
+        txt.print_uwbin(sw as uword, true)
         c64.CHROUT('\n')
         sw = shiftrsw2()
-        c64scr.print_uwbin(sw as uword, true)
+        txt.print_uwbin(sw as uword, true)
         c64.CHROUT('\n')
         sw = shiftrsw3()
-        c64scr.print_uwbin(sw as uword, true)
+        txt.print_uwbin(sw as uword, true)
         c64.CHROUT('\n')
         sw = shiftrsw4()
-        c64scr.print_uwbin(sw as uword, true)
+        txt.print_uwbin(sw as uword, true)
         c64.CHROUT('\n')
         sw = shiftrsw5()
-        c64scr.print_uwbin(sw as uword, true)
+        txt.print_uwbin(sw as uword, true)
         c64.CHROUT('\n')
         sw = shiftrsw6()
-        c64scr.print_uwbin(sw as uword, true)
+        txt.print_uwbin(sw as uword, true)
         c64.CHROUT('\n')
         sw = shiftrsw7()
-        c64scr.print_uwbin(sw as uword, true)
+        txt.print_uwbin(sw as uword, true)
         c64.CHROUT('\n')
         sw = shiftrsw8()
-        c64scr.print_uwbin(sw as uword, true)
+        txt.print_uwbin(sw as uword, true)
         c64.CHROUT('\n')
         sw = shiftrsw9()
-        c64scr.print_uwbin(sw as uword, true)
+        txt.print_uwbin(sw as uword, true)
         c64.CHROUT('\n')
         sw = shiftrsw10()
-        c64scr.print_uwbin(sw as uword, true)
+        txt.print_uwbin(sw as uword, true)
         c64.CHROUT('\n')
         sw = shiftrsw11()
-        c64scr.print_uwbin(sw as uword, true)
+        txt.print_uwbin(sw as uword, true)
         c64.CHROUT('\n')
         sw = shiftrsw12()
-        c64scr.print_uwbin(sw as uword, true)
+        txt.print_uwbin(sw as uword, true)
         c64.CHROUT('\n')
         sw = shiftrsw13()
-        c64scr.print_uwbin(sw as uword, true)
+        txt.print_uwbin(sw as uword, true)
         c64.CHROUT('\n')
         sw = shiftrsw14()
-        c64scr.print_uwbin(sw as uword, true)
+        txt.print_uwbin(sw as uword, true)
         c64.CHROUT('\n')
         sw = shiftrsw15()
-        c64scr.print_uwbin(sw as uword, true)
+        txt.print_uwbin(sw as uword, true)
         c64.CHROUT('\n')
         sw = shiftrsw16()
-        c64scr.print_uwbin(sw as uword, true)
+        txt.print_uwbin(sw as uword, true)
         c64.CHROUT('\n')
         sw = shiftrsw17()
-        c64scr.print_uwbin(sw as uword, true)
+        txt.print_uwbin(sw as uword, true)
         c64.CHROUT('\n')
 
     }

examples/arithmetic/div.p8

@@ -1,6 +1,5 @@
-%import c64lib
-%import c64utils
 %import c64flt
+%import c64textio
 %zeropage basicsafe
 
 main {
@@ -29,75 +28,75 @@ main {
     sub div_ubyte(ubyte a1, ubyte a2, ubyte c) {
         ubyte r = a1/a2
         if r==c
-            c64scr.print(" ok  ")
+            txt.print(" ok  ")
         else
-            c64scr.print("err! ")
-        c64scr.print("ubyte ")
-        c64scr.print_ub(a1)
-        c64scr.print(" / ")
-        c64scr.print_ub(a2)
-        c64scr.print(" = ")
-        c64scr.print_ub(r)
+            txt.print("err! ")
+        txt.print("ubyte ")
+        txt.print_ub(a1)
+        txt.print(" / ")
+        txt.print_ub(a2)
+        txt.print(" = ")
+        txt.print_ub(r)
         c64.CHROUT('\n')
     }
 
     sub div_byte(byte a1, byte a2, byte c) {
         byte r = a1/a2
         if r==c
-            c64scr.print(" ok  ")
+            txt.print(" ok  ")
         else
-            c64scr.print("err! ")
-        c64scr.print("byte ")
-        c64scr.print_b(a1)
-        c64scr.print(" / ")
-        c64scr.print_b(a2)
-        c64scr.print(" = ")
-        c64scr.print_b(r)
+            txt.print("err! ")
+        txt.print("byte ")
+        txt.print_b(a1)
+        txt.print(" / ")
+        txt.print_b(a2)
+        txt.print(" = ")
+        txt.print_b(r)
         c64.CHROUT('\n')
     }
 
     sub div_uword(uword a1, uword  a2, uword c) {
         uword  r = a1/a2
         if r==c
-            c64scr.print(" ok  ")
+            txt.print(" ok  ")
         else
-            c64scr.print("err! ")
-        c64scr.print("uword ")
-        c64scr.print_uw(a1)
-        c64scr.print(" / ")
-        c64scr.print_uw(a2)
-        c64scr.print(" = ")
-        c64scr.print_uw(r)
+            txt.print("err! ")
+        txt.print("uword ")
+        txt.print_uw(a1)
+        txt.print(" / ")
+        txt.print_uw(a2)
+        txt.print(" = ")
+        txt.print_uw(r)
         c64.CHROUT('\n')
     }
 
     sub div_word(word a1, word a2, word c) {
         word r = a1/a2
         if r==c
-            c64scr.print(" ok  ")
+            txt.print(" ok  ")
         else
-            c64scr.print("err! ")
-        c64scr.print("word ")
-        c64scr.print_w(a1)
-        c64scr.print(" / ")
-        c64scr.print_w(a2)
-        c64scr.print(" = ")
-        c64scr.print_w(r)
+            txt.print("err! ")
+        txt.print("word ")
+        txt.print_w(a1)
+        txt.print(" / ")
+        txt.print_w(a2)
+        txt.print(" = ")
+        txt.print_w(r)
         c64.CHROUT('\n')
     }
 
     sub div_float(float  a1, float a2, float  c) {
         float r = a1/a2
         if abs(r-c)<0.00001
-            c64scr.print(" ok  ")
+            txt.print(" ok  ")
         else
-            c64scr.print("err! ")
+            txt.print("err! ")
 
-        c64scr.print("float ")
+        txt.print("float ")
         c64flt.print_f(a1)
-        c64scr.print(" / ")
+        txt.print(" / ")
         c64flt.print_f(a2)
-        c64scr.print(" = ")
+        txt.print(" = ")
         c64flt.print_f(r)
         c64.CHROUT('\n')
     }

examples/arithmetic/minus.p8

@@ -1,6 +1,5 @@
-%import c64lib
-%import c64utils
 %import c64flt
+%import c64textio
 %zeropage basicsafe
 
 main {
@@ -37,75 +36,75 @@ main {
     sub minus_ubyte(ubyte a1, ubyte a2, ubyte c) {
         ubyte r = a1-a2
         if r==c
-            c64scr.print(" ok  ")
+            txt.print(" ok  ")
         else
-            c64scr.print("err! ")
-        c64scr.print("ubyte ")
-        c64scr.print_ub(a1)
-        c64scr.print(" - ")
-        c64scr.print_ub(a2)
-        c64scr.print(" = ")
-        c64scr.print_ub(r)
+            txt.print("err! ")
+        txt.print("ubyte ")
+        txt.print_ub(a1)
+        txt.print(" - ")
+        txt.print_ub(a2)
+        txt.print(" = ")
+        txt.print_ub(r)
         c64.CHROUT('\n')
     }
 
     sub minus_byte(byte a1, byte a2, byte c) {
         byte r = a1-a2
         if r==c
-            c64scr.print(" ok  ")
+            txt.print(" ok  ")
         else
-            c64scr.print("err! ")
-        c64scr.print("byte ")
-        c64scr.print_b(a1)
-        c64scr.print(" - ")
-        c64scr.print_b(a2)
-        c64scr.print(" = ")
-        c64scr.print_b(r)
+            txt.print("err! ")
+        txt.print("byte ")
+        txt.print_b(a1)
+        txt.print(" - ")
+        txt.print_b(a2)
+        txt.print(" = ")
+        txt.print_b(r)
         c64.CHROUT('\n')
     }
 
     sub minus_uword(uword a1, uword  a2, uword c) {
         uword  r = a1-a2
         if r==c
-            c64scr.print(" ok  ")
+            txt.print(" ok  ")
         else
-            c64scr.print("err! ")
-        c64scr.print("uword ")
-        c64scr.print_uw(a1)
-        c64scr.print(" - ")
-        c64scr.print_uw(a2)
-        c64scr.print(" = ")
-        c64scr.print_uw(r)
+            txt.print("err! ")
+        txt.print("uword ")
+        txt.print_uw(a1)
+        txt.print(" - ")
+        txt.print_uw(a2)
+        txt.print(" = ")
+        txt.print_uw(r)
         c64.CHROUT('\n')
     }
 
     sub minus_word(word a1, word a2, word c) {
         word r = a1-a2
         if r==c
-            c64scr.print(" ok  ")
+            txt.print(" ok  ")
         else
-            c64scr.print("err! ")
-        c64scr.print("word ")
-        c64scr.print_w(a1)
-        c64scr.print(" - ")
-        c64scr.print_w(a2)
-        c64scr.print(" = ")
-        c64scr.print_w(r)
+            txt.print("err! ")
+        txt.print("word ")
+        txt.print_w(a1)
+        txt.print(" - ")
+        txt.print_w(a2)
+        txt.print(" = ")
+        txt.print_w(r)
         c64.CHROUT('\n')
     }
 
     sub minus_float(float  a1, float a2, float  c) {
         float r = a1-a2
         if abs(r-c)<0.00001
-            c64scr.print(" ok  ")
+            txt.print(" ok  ")
         else
-            c64scr.print("err! ")
+            txt.print("err! ")
 
-        c64scr.print("float ")
+        txt.print("float ")
         c64flt.print_f(a1)
-        c64scr.print(" - ")
+        txt.print(" - ")
         c64flt.print_f(a2)
-        c64scr.print(" = ")
+        txt.print(" = ")
         c64flt.print_f(r)
         c64.CHROUT('\n')
     }

examples/arithmetic/mult.p8

@@ -1,6 +1,5 @@
-%import c64lib
-%import c64utils
 %import c64flt
+%import c64textio
 %zeropage basicsafe
 
 main {
@@ -31,75 +30,75 @@ main {
     sub mul_ubyte(ubyte a1, ubyte a2, ubyte c) {
         ubyte r = a1*a2
         if r==c
-            c64scr.print(" ok  ")
+            txt.print(" ok  ")
         else
-            c64scr.print("err! ")
-        c64scr.print("ubyte ")
-        c64scr.print_ub(a1)
-        c64scr.print(" * ")
-        c64scr.print_ub(a2)
-        c64scr.print(" = ")
-        c64scr.print_ub(r)
+            txt.print("err! ")
+        txt.print("ubyte ")
+        txt.print_ub(a1)
+        txt.print(" * ")
+        txt.print_ub(a2)
+        txt.print(" = ")
+        txt.print_ub(r)
         c64.CHROUT('\n')
     }
 
     sub mul_byte(byte a1, byte a2, byte c) {
         byte r = a1*a2
         if r==c
-            c64scr.print(" ok  ")
+            txt.print(" ok  ")
         else
-            c64scr.print("err! ")
-        c64scr.print("byte ")
-        c64scr.print_b(a1)
-        c64scr.print(" * ")
-        c64scr.print_b(a2)
-        c64scr.print(" = ")
-        c64scr.print_b(r)
+            txt.print("err! ")
+        txt.print("byte ")
+        txt.print_b(a1)
+        txt.print(" * ")
+        txt.print_b(a2)
+        txt.print(" = ")
+        txt.print_b(r)
         c64.CHROUT('\n')
     }
 
     sub mul_uword(uword a1, uword  a2, uword c) {
         uword  r = a1*a2
         if r==c
-            c64scr.print(" ok  ")
+            txt.print(" ok  ")
         else
-            c64scr.print("err! ")
-        c64scr.print("uword ")
-        c64scr.print_uw(a1)
-        c64scr.print(" * ")
-        c64scr.print_uw(a2)
-        c64scr.print(" = ")
-        c64scr.print_uw(r)
+            txt.print("err! ")
+        txt.print("uword ")
+        txt.print_uw(a1)
+        txt.print(" * ")
+        txt.print_uw(a2)
+        txt.print(" = ")
+        txt.print_uw(r)
         c64.CHROUT('\n')
     }
 
     sub mul_word(word a1, word a2, word c) {
         word r = a1*a2
         if r==c
-            c64scr.print(" ok  ")
+            txt.print(" ok  ")
         else
-            c64scr.print("err! ")
-        c64scr.print("word ")
-        c64scr.print_w(a1)
-        c64scr.print(" * ")
-        c64scr.print_w(a2)
-        c64scr.print(" = ")
-        c64scr.print_w(r)
+            txt.print("err! ")
+        txt.print("word ")
+        txt.print_w(a1)
+        txt.print(" * ")
+        txt.print_w(a2)
+        txt.print(" = ")
+        txt.print_w(r)
         c64.CHROUT('\n')
     }
 
     sub mul_float(float  a1, float a2, float  c) {
         float r = a1*a2
         if abs(r-c)<0.00001
-            c64scr.print(" ok  ")
+            txt.print(" ok  ")
         else
-            c64scr.print("err! ")
+            txt.print("err! ")
 
-        c64scr.print("float ")
+        txt.print("float ")
         c64flt.print_f(a1)
-        c64scr.print(" * ")
+        txt.print(" * ")
         c64flt.print_f(a2)
-        c64scr.print(" = ")
+        txt.print(" = ")
         c64flt.print_f(r)
         c64.CHROUT('\n')
     }

examples/arithmetic/plus.p8

@@ -1,6 +1,5 @@
-%import c64lib
-%import c64utils
 %import c64flt
+%import c64textio
 %zeropage basicsafe
 
 main {
@@ -35,75 +34,75 @@ main {
     sub plus_ubyte(ubyte a1, ubyte a2, ubyte c) {
         ubyte r = a1+a2
         if r==c
-            c64scr.print(" ok  ")
+            txt.print(" ok  ")
         else
-            c64scr.print("err! ")
-        c64scr.print("ubyte ")
-        c64scr.print_ub(a1)
-        c64scr.print(" + ")
-        c64scr.print_ub(a2)
-        c64scr.print(" = ")
-        c64scr.print_ub(r)
+            txt.print("err! ")
+        txt.print("ubyte ")
+        txt.print_ub(a1)
+        txt.print(" + ")
+        txt.print_ub(a2)
+        txt.print(" = ")
+        txt.print_ub(r)
         c64.CHROUT('\n')
     }
 
     sub plus_byte(byte a1, byte a2, byte c) {
         byte r = a1+a2
         if r==c
-            c64scr.print(" ok  ")
+            txt.print(" ok  ")
         else
-            c64scr.print("err! ")
-        c64scr.print("byte ")
-        c64scr.print_b(a1)
-        c64scr.print(" + ")
-        c64scr.print_b(a2)
-        c64scr.print(" = ")
-        c64scr.print_b(r)
+            txt.print("err! ")
+        txt.print("byte ")
+        txt.print_b(a1)
+        txt.print(" + ")
+        txt.print_b(a2)
+        txt.print(" = ")
+        txt.print_b(r)
         c64.CHROUT('\n')
     }
 
     sub plus_uword(uword a1, uword  a2, uword c) {
         uword  r = a1+a2
         if r==c
-            c64scr.print(" ok  ")
+            txt.print(" ok  ")
         else
-            c64scr.print("err! ")
-        c64scr.print("uword ")
-        c64scr.print_uw(a1)
-        c64scr.print(" + ")
-        c64scr.print_uw(a2)
-        c64scr.print(" = ")
-        c64scr.print_uw(r)
+            txt.print("err! ")
+        txt.print("uword ")
+        txt.print_uw(a1)
+        txt.print(" + ")
+        txt.print_uw(a2)
+        txt.print(" = ")
+        txt.print_uw(r)
         c64.CHROUT('\n')
     }
 
     sub plus_word(word a1, word a2, word c) {
         word r = a1+a2
         if r==c
-            c64scr.print(" ok  ")
+            txt.print(" ok  ")
         else
-            c64scr.print("err! ")
-        c64scr.print("word ")
-        c64scr.print_w(a1)
-        c64scr.print(" + ")
-        c64scr.print_w(a2)
-        c64scr.print(" = ")
-        c64scr.print_w(r)
+            txt.print("err! ")
+        txt.print("word ")
+        txt.print_w(a1)
+        txt.print(" + ")
+        txt.print_w(a2)
+        txt.print(" = ")
+        txt.print_w(r)
         c64.CHROUT('\n')
     }
 
     sub plus_float(float  a1, float a2, float  c) {
         float r = a1+a2
         if abs(r-c)<0.00001
-            c64scr.print(" ok  ")
+            txt.print(" ok  ")
         else
-            c64scr.print("err! ")
+            txt.print("err! ")
 
-        c64scr.print("float ")
+        txt.print("float ")
         c64flt.print_f(a1)
-        c64scr.print(" + ")
+        txt.print(" + ")
         c64flt.print_f(a2)
-        c64scr.print(" = ")
+        txt.print(" = ")
         c64flt.print_f(r)
         c64.CHROUT('\n')
     }

examples/arithmetic/postincrdecr.p8

@@ -1,13 +1,12 @@
-%import c64utils
 %import c64flt
-%option enable_floats
+%import c64textio
 %zeropage basicsafe
 
 main {
 
     sub start()  {
 
-        c64scr.plot(0,24)
+        txt.plot(0,24)
 
         ubyte Y
         ubyte ub=200
@@ -21,7 +20,7 @@ main {
         word[3] warr = -1000
         float[3] flarr = 999.99
 
-        c64scr.print("++\n")
+        txt.print("++\n")
         ub++
         bb++
         uw++
@@ -52,7 +51,7 @@ main {
         check_uw(uwarr[1], 2001)
         check_w(warr[1], -999)
 
-        c64scr.print("--\n")
+        txt.print("--\n")
         ub--
         bb--
         uw--
@@ -81,58 +80,58 @@ main {
 
     sub check_ub(ubyte value, ubyte expected) {
         if value==expected
-            c64scr.print(" ok  ")
+            txt.print(" ok  ")
         else
-            c64scr.print("err! ")
-        c64scr.print(" ubyte ")
-        c64scr.print_ub(value)
+            txt.print("err! ")
+        txt.print(" ubyte ")
+        txt.print_ub(value)
         c64.CHROUT(',')
-        c64scr.print_ub(expected)
+        txt.print_ub(expected)
         c64.CHROUT('\n')
     }
 
     sub check_b(byte value, byte expected) {
         if value==expected
-            c64scr.print(" ok  ")
+            txt.print(" ok  ")
         else
-            c64scr.print("err! ")
-        c64scr.print(" byte ")
-        c64scr.print_b(value)
+            txt.print("err! ")
+        txt.print(" byte ")
+        txt.print_b(value)
         c64.CHROUT(',')
-        c64scr.print_b(expected)
+        txt.print_b(expected)
         c64.CHROUT('\n')
     }
 
     sub check_uw(uword value, uword expected) {
         if value==expected
-            c64scr.print(" ok  ")
+            txt.print(" ok  ")
         else
-            c64scr.print("err! ")
-        c64scr.print(" uword ")
-        c64scr.print_uw(value)
+            txt.print("err! ")
+        txt.print(" uword ")
+        txt.print_uw(value)
         c64.CHROUT(',')
-        c64scr.print_uw(expected)
+        txt.print_uw(expected)
         c64.CHROUT('\n')
     }
 
     sub check_w(word value, word expected) {
         if value==expected
-            c64scr.print(" ok  ")
+            txt.print(" ok  ")
         else
-            c64scr.print("err! ")
-        c64scr.print(" word ")
-        c64scr.print_w(value)
+            txt.print("err! ")
+        txt.print(" word ")
+        txt.print_w(value)
         c64.CHROUT(',')
-        c64scr.print_w(expected)
+        txt.print_w(expected)
         c64.CHROUT('\n')
     }
 
     sub check_fl(float value, float expected) {
         if value==expected
-            c64scr.print(" ok  ")
+            txt.print(" ok  ")
         else
-            c64scr.print("err! ")
-        c64scr.print(" float ")
+            txt.print("err! ")
+        txt.print(" float ")
         c64flt.print_f(value)
         c64.CHROUT(',')
         c64flt.print_f(expected)

examples/arithmetic/remainder.p8

@@ -1,6 +1,4 @@
-%import c64lib
-%import c64utils
-%import c64flt
+%import c64textio
 %zeropage basicsafe
 
 main {
@@ -20,30 +18,30 @@ main {
     sub remainder_ubyte(ubyte a1, ubyte a2, ubyte c) {
         ubyte r = a1%a2
         if r==c
-            c64scr.print(" ok  ")
+            txt.print(" ok  ")
         else
-            c64scr.print("err! ")
-        c64scr.print("ubyte ")
-        c64scr.print_ub(a1)
-        c64scr.print(" % ")
-        c64scr.print_ub(a2)
-        c64scr.print(" = ")
-        c64scr.print_ub(r)
+            txt.print("err! ")
+        txt.print("ubyte ")
+        txt.print_ub(a1)
+        txt.print(" % ")
+        txt.print_ub(a2)
+        txt.print(" = ")
+        txt.print_ub(r)
         c64.CHROUT('\n')
     }
 
     sub remainder_uword(uword a1, uword  a2, uword c) {
         uword  r = a1%a2
         if r==c
-            c64scr.print(" ok  ")
+            txt.print(" ok  ")
         else
-            c64scr.print("err! ")
-        c64scr.print("uword ")
-        c64scr.print_uw(a1)
-        c64scr.print(" % ")
-        c64scr.print_uw(a2)
-        c64scr.print(" = ")
-        c64scr.print_uw(r)
+            txt.print("err! ")
+        txt.print("uword ")
+        txt.print_uw(a1)
+        txt.print(" % ")
+        txt.print_uw(a2)
+        txt.print(" = ")
+        txt.print_uw(r)
         c64.CHROUT('\n')
     }
 }

examples/arithmetic/sgn.p8

@@ -1,4 +1,5 @@
 %import c64flt
+%import c64textio
 %zeropage basicsafe
 
 main {
@@ -18,113 +19,113 @@ main {
         b1 = 10
         b2 = 10
         if sgn(b2-b1) != 0
-            c64scr.print("sgn1 error1\n")
+            txt.print("sgn1 error1\n")
 
         b1 = -100
         b2 = -100
         if sgn(b2-b1) != 0
-            c64scr.print("sgn1 error2\n")
+            txt.print("sgn1 error2\n")
 
         ub1 = 200
         ub2 = 200
         if sgn(ub2-ub1) != 0
-            c64scr.print("sgn1 error3\n")
+            txt.print("sgn1 error3\n")
 
         w1 = 100
         w2 = 100
         if sgn(w2-w1) != 0
-            c64scr.print("sgn1 error4\n")
+            txt.print("sgn1 error4\n")
 
         w1 = -2000
         w2 = -2000
         if sgn(w2-w1) != 0
-            c64scr.print("sgn1 error5\n")
+            txt.print("sgn1 error5\n")
 
         uw1 = 999
         uw2 = 999
         if sgn(uw2-uw1) != 0
-            c64scr.print("sgn1 error6\n")
+            txt.print("sgn1 error6\n")
 
         f1 = 3.45
         f2 = 3.45
         if sgn(f2-f1) != 0
-            c64scr.print("sgn1 error7\n")
+            txt.print("sgn1 error7\n")
 
 
         ; -1
         b1 = 11
         b2 = 10
         if sgn(b2-b1) != -1
-            c64scr.print("sgn2 error1\n")
+            txt.print("sgn2 error1\n")
 
         b1 = -10
         b2 = -100
         if sgn(b2-b1) != -1
-            c64scr.print("sgn2 error2\n")
+            txt.print("sgn2 error2\n")
 
         ub1 = 202
         ub2 = 200
         if sgn(ub2 as byte - ub1 as byte) != -1
-            c64scr.print("sgn2 error3\n")
+            txt.print("sgn2 error3\n")
 
         w1 = 101
         w2 = 100
         if sgn(w2-w1) != -1
-            c64scr.print("sgn2 error4\n")
+            txt.print("sgn2 error4\n")
 
         w1 = -200
         w2 = -2000
         if sgn(w2-w1) != -1
-            c64scr.print("sgn2 error5\n")
+            txt.print("sgn2 error5\n")
 
         uw1 = 2222
         uw2 = 999
         if sgn((uw2 as word) - (uw1 as word)) != -1
-            c64scr.print("sgn2 error6a\n")
+            txt.print("sgn2 error6a\n")
         if sgn(uw2 - uw1) != 1      ; always 0 or 1 if unsigned
-            c64scr.print("sgn2 error6b\n")
+            txt.print("sgn2 error6b\n")
 
         f1 = 3.45
         f2 = 1.11
         if sgn(f2-f1) != -1
-            c64scr.print("sgn2 error7\n")
+            txt.print("sgn2 error7\n")
 
         ; +1
         b1 = 11
         b2 = 20
         if sgn(b2-b1) != 1
-            c64scr.print("sgn3 error1\n")
+            txt.print("sgn3 error1\n")
 
         b1 = -10
         b2 = -1
         if sgn(b2-b1) != 1
-            c64scr.print("sgn3 error2\n")
+            txt.print("sgn3 error2\n")
 
         ub1 = 202
         ub2 = 205
         if sgn(ub2-ub1) != 1
-            c64scr.print("sgn3 error3\n")
+            txt.print("sgn3 error3\n")
 
         w1 = 101
         w2 = 200
         if sgn(w2-w1) != 1
-            c64scr.print("sgn3 error4\n")
+            txt.print("sgn3 error4\n")
 
         w1 = -200
         w2 = -20
         if sgn(w2-w1) != 1
-            c64scr.print("sgn3 error5\n")
+            txt.print("sgn3 error5\n")
 
         uw1 = 2222
         uw2 = 9999
         if sgn(uw2-uw1) != 1
-            c64scr.print("sgn3 error6\n")
+            txt.print("sgn3 error6\n")
 
         f1 = 3.45
         f2 = 5.11
         if sgn(f2-f1) != 1
-            c64scr.print("sgn3 error7\n")
+            txt.print("sgn3 error7\n")
 
-        c64scr.print("should see no sgn errors\n")
+        txt.print("should see no sgn errors\n")
     }
  }

examples/balloonflight.p8

@@ -1,5 +1,5 @@
 %import c64lib
-%import c64utils
+%import c64textio
 %zeropage basicsafe
 
 main {
@@ -15,7 +15,7 @@ main {
 
         c64.SCROLX &= %11110111     ; 38 column mode
 
-        c64utils.set_rasterirq(1)     ; enable animation
+        c64.set_rasterirq(1)     ; enable animation
 
         ubyte target_height = 10
         ubyte active_height = 24
@@ -43,7 +43,7 @@ main {
             }
 
             perform_scroll = false
-            c64scr.scroll_left_full(true)
+            txt.scroll_left_full(true)
             if c64.RASTER & 1
                 c64.SPXY[1] ++
             else
@@ -51,17 +51,17 @@ main {
 
             ubyte yy
             for yy in 0 to active_height-1 {
-                c64scr.setcc(39, yy, 32, 2)         ; clear top of screen
+                txt.setcc(39, yy, 32, 2)         ; clear top of screen
             }
-            c64scr.setcc(39, active_height, mountain, 8)    ; mountain edge
+            txt.setcc(39, active_height, mountain, 8)    ; mountain edge
             for yy in active_height+1 to 24 {
-                c64scr.setcc(39, yy, 160, 8)        ; draw mountain
+                txt.setcc(39, yy, 160, 8)        ; draw mountain
             }
 
             yy = rnd()
             if yy > 100 {
                 ; draw a star
-                c64scr.setcc(39, yy % (active_height-1), '.', rnd())
+                txt.setcc(39, yy % (active_height-1), '.', rnd())
             }
 
             if yy > 200 {
@@ -74,12 +74,12 @@ main {
                     tree = 65
                 if rnd() > 130
                     treecolor = 13
-                c64scr.setcc(39, active_height, tree, treecolor)
+                txt.setcc(39, active_height, tree, treecolor)
             }
 
             if yy > 235 {
                 ; draw a camel
-                c64scr.setcc(39, active_height, 94, 9)
+                txt.setcc(39, active_height, 94, 9)
             }
         }
     }

examples/bdmusic-irq.p8

@@ -1,11 +1,12 @@
-%zeropage basicsafe
 %import c64lib
+%import c64textio
+%zeropage basicsafe
 
 main {
 
     sub start() {
-        c64scr.print("playing the music from boulderdash,\nmade in 1984 by peter liepa.\n\n")
-        c64utils.set_rasterirq(60)     ; enable raster irq
+        txt.print("playing the music from boulderdash,\nmade in 1984 by peter liepa.\n\n")
+        c64.set_rasterirq(60)     ; enable raster irq
     }
 }
 

examples/bdmusic.p8

@@ -1,4 +1,4 @@
-%import c64lib
+%import c64textio
 
 main {
 
@@ -12,7 +12,7 @@ sub start() {
     c64.SR2 = %00000000
     c64.MVOL = 15
 
-    c64scr.print("will play the music from boulderdash,\nmade in 1984 by peter liepa.\npress enter to start: ")
+    txt.print("will play the music from boulderdash,\nmade in 1984 by peter liepa.\npress enter to start: ")
     void c64.CHRIN()
     c64.CLEARSCR()
 
@@ -37,19 +37,20 @@ sub start() {
 }
 
 sub delay() {
-    repeat 32 {
-        while c64.RASTER {
+    repeat 8 {
+        ubyte jiffy = c64.TIME_LO
+        while c64.TIME_LO==jiffy {
         }
     }
 }
 
 sub print_notes(ubyte n1, ubyte n2) {
     c64.CHROUT('\n')
-    c64scr.plot(n1/2, 24)
-    c64.COLOR=7
+    txt.plot(n1/2, 24)
+    txt.color(7)
     c64.CHROUT('Q')
-    c64scr.plot(n2/2, 24)
-    c64.COLOR=4
+    txt.plot(n2/2, 24)
+    txt.color(4)
     c64.CHROUT('Q')
 }
 

examples/c64graphics.p8

@@ -1,252 +0,0 @@
-%import c64lib
-
-; bitmap pixel graphics module for the C64
-; only black/white monchrome for now
-
-; you could put this code at $4000 which is after the bitmap screen in memory ($2000-$3fff),
-; this leaves more space for user program code.
-
-graphics {
-    const uword bitmap_address = $2000
-
-    sub enable_bitmap_mode() {
-        ; enable bitmap screen, erase it and set colors to black/white.
-        c64.SCROLY |= %00100000
-        c64.VMCSB = (c64.VMCSB & %11110000) | %00001000   ; $2000-$3fff
-        memset(bitmap_address, 320*200/8, 0)
-        c64scr.clear_screen($10, 0)         ; pixel color $1 (white) backround $0 (black)
-    }
-
-    sub line(uword x1, ubyte y1, uword x2, ubyte y2) {
-        ; Bresenham algorithm.
-        ; This code special cases various quadrant loops to allow simple ++ and -- operations.
-        if y1>y2 {
-            ; make sure dy is always positive to avoid 8 instead of just 4 special cases
-            swap(x1, x2)
-            swap(y1, y2)
-        }
-        word d = 0
-        ubyte positive_ix = true
-        word dx = x2 - x1 as word
-        word dy = y2 as word - y1 as word
-        if dx < 0 {
-            dx = -dx
-            positive_ix = false
-        }
-        dx *= 2
-        dy *= 2
-        plotx = x1
-
-        if dx >= dy {
-            if positive_ix {
-                repeat {
-                    plot(y1)
-                    if plotx==x2
-                        return
-                    plotx++
-                    d += dy
-                    if d > dx {
-                        y1++
-                        d -= dx
-                    }
-                }
-            } else {
-                repeat {
-                    plot(y1)
-                    if plotx==x2
-                        return
-                    plotx--
-                    d += dy
-                    if d > dx {
-                        y1++
-                        d -= dx
-                    }
-                }
-            }
-        }
-        else {
-            if positive_ix {
-                repeat {
-                    plot(y1)
-                    if y1 == y2
-                        return
-                    y1++
-                    d += dx
-                    if d > dy {
-                        plotx++
-                        d -= dy
-                    }
-                }
-            } else {
-                repeat {
-                    plot(y1)
-                    if y1 == y2
-                        return
-                    y1++
-                    d += dx
-                    if d > dy {
-                        plotx--
-                        d -= dy
-                    }
-                }
-            }
-        }
-    }
-
-    sub circle(uword xcenter, ubyte ycenter, ubyte radius) {
-        ; Midpoint algorithm
-        ubyte ploty
-        ubyte xx = radius
-        ubyte yy = 0
-        byte decisionOver2 = 1-xx as byte
-
-        while xx>=yy {
-            plotx = xcenter + xx
-            ploty = ycenter + yy
-            plot(ploty)
-            plotx = xcenter - xx
-            plot(ploty)
-            plotx = xcenter + xx
-            ploty = ycenter - yy
-            plot(ploty)
-            plotx = xcenter - xx
-            plot(ploty)
-            plotx = xcenter + yy
-            ploty = ycenter + xx
-            plot(ploty)
-            plotx = xcenter - yy
-            plot(ploty)
-            plotx = xcenter + yy
-            ploty = ycenter - xx
-            plot(ploty)
-            plotx = xcenter - yy
-            plot(ploty)
-            yy++
-            if decisionOver2<=0
-                decisionOver2 += 2*yy+1
-            else {
-                xx--
-                decisionOver2 += 2*(yy-xx)+1
-            }
-        }
-    }
-
-    sub disc(uword cx, ubyte cy, ubyte radius) {
-        ; Midpoint algorithm, filled
-        ubyte xx = radius
-        ubyte yy = 0
-        byte decisionOver2 = 1-xx as byte
-
-        while xx>=yy {
-            ubyte cy_plus_yy = cy + yy
-            ubyte cy_min_yy = cy - yy
-            ubyte cy_plus_xx = cy + xx
-            ubyte cy_min_xx = cy - xx
-
-            for plotx in cx to cx+xx {
-                plot(cy_plus_yy)
-                plot(cy_min_yy)
-            }
-            for plotx in cx-xx to cx-1 {
-                plot(cy_plus_yy)
-                plot(cy_min_yy)
-            }
-            for plotx in cx to cx+yy {
-                plot(cy_plus_xx)
-                plot(cy_min_xx)
-            }
-            for plotx in cx-yy to cx {
-                plot(cy_plus_xx)
-                plot(cy_min_xx)
-            }
-            yy++
-            if decisionOver2<=0
-                decisionOver2 += 2*yy+1
-            else {
-                xx--
-                decisionOver2 += 2*(yy-xx)+1
-            }
-        }
-    }
-
-
-; here is the non-asm code for the plot routine below:
-;    sub plot_nonasm(uword px, ubyte py) {
-;        ubyte[] ormask = [128, 64, 32, 16, 8, 4, 2, 1]
-;        uword addr = bitmap_address + 320*(py>>3) + (py & 7) + (px & %0000000111111000)
-;        @(addr) |= ormask[lsb(px) & 7]
-;    }
-
-    uword plotx     ; 0..319        ; separate 'parameter' for plot()
-
-    asmsub plot(ubyte ploty @A) {           ; plotx is 16 bits 0 to 319... doesn't fit in a register
-        %asm {{
-        tay
-        stx  c64.SCRATCH_ZPREGX
-        lda  plotx+1
-        sta  c64.SCRATCH_ZPWORD2+1
-        lsr  a            ; 0
-        sta  c64.SCRATCH_ZPWORD2
-        lda  plotx
-        pha
-        and  #7
-        tax
-
-        lda  _y_lookup_lo,y
-        clc
-        adc  c64.SCRATCH_ZPWORD2
-        sta  c64.SCRATCH_ZPWORD2
-        lda  _y_lookup_hi,y
-        adc  c64.SCRATCH_ZPWORD2+1
-        sta  c64.SCRATCH_ZPWORD2+1
-
-        pla     ; plotx
-        and  #%11111000
-        tay
-        lda  (c64.SCRATCH_ZPWORD2),y
-        ora  _ormask,x
-        sta  (c64.SCRATCH_ZPWORD2),y
-
-        ldx  c64.SCRATCH_ZPREGX
-        rts
-
-_ormask     .byte 128, 64, 32, 16, 8, 4, 2, 1
-
-; note: this can be even faster if we also have a 256 byte x-lookup table, but hey.
-; see http://codebase64.org/doku.php?id=base:various_techniques_to_calculate_adresses_fast_common_screen_formats_for_pixel_graphics
-; the y lookup tables encodes this formula:  bitmap_address + 320*(py>>3) + (py & 7)    (y from 0..199)
-_y_lookup_hi
-            .byte  $20, $20, $20, $20, $20, $20, $20, $20, $21, $21, $21, $21, $21, $21, $21, $21
-            .byte  $22, $22, $22, $22, $22, $22, $22, $22, $23, $23, $23, $23, $23, $23, $23, $23
-            .byte  $25, $25, $25, $25, $25, $25, $25, $25, $26, $26, $26, $26, $26, $26, $26, $26
-            .byte  $27, $27, $27, $27, $27, $27, $27, $27, $28, $28, $28, $28, $28, $28, $28, $28
-            .byte  $2a, $2a, $2a, $2a, $2a, $2a, $2a, $2a, $2b, $2b, $2b, $2b, $2b, $2b, $2b, $2b
-            .byte  $2c, $2c, $2c, $2c, $2c, $2c, $2c, $2c, $2d, $2d, $2d, $2d, $2d, $2d, $2d, $2d
-            .byte  $2f, $2f, $2f, $2f, $2f, $2f, $2f, $2f, $30, $30, $30, $30, $30, $30, $30, $30
-            .byte  $31, $31, $31, $31, $31, $31, $31, $31, $32, $32, $32, $32, $32, $32, $32, $32
-            .byte  $34, $34, $34, $34, $34, $34, $34, $34, $35, $35, $35, $35, $35, $35, $35, $35
-            .byte  $36, $36, $36, $36, $36, $36, $36, $36, $37, $37, $37, $37, $37, $37, $37, $37
-            .byte  $39, $39, $39, $39, $39, $39, $39, $39, $3a, $3a, $3a, $3a, $3a, $3a, $3a, $3a
-            .byte  $3b, $3b, $3b, $3b, $3b, $3b, $3b, $3b, $3c, $3c, $3c, $3c, $3c, $3c, $3c, $3c
-            .byte  $3e, $3e, $3e, $3e, $3e, $3e, $3e, $3e
-
-_y_lookup_lo
-            .byte $00, $01, $02, $03, $04, $05, $06, $07, $40, $41, $42, $43, $44, $45, $46, $47
-            .byte $80, $81, $82, $83, $84, $85, $86, $87, $c0, $c1, $c2, $c3, $c4, $c5, $c6, $c7
-            .byte $00, $01, $02, $03, $04, $05, $06, $07, $40, $41, $42, $43, $44, $45, $46, $47
-            .byte $80, $81, $82, $83, $84, $85, $86, $87, $c0, $c1, $c2, $c3, $c4, $c5, $c6, $c7
-            .byte $00, $01, $02, $03, $04, $05, $06, $07, $40, $41, $42, $43, $44, $45, $46, $47
-            .byte $80, $81, $82, $83, $84, $85, $86, $87, $c0, $c1, $c2, $c3, $c4, $c5, $c6, $c7
-            .byte $00, $01, $02, $03, $04, $05, $06, $07, $40, $41, $42, $43, $44, $45, $46, $47
-            .byte $80, $81, $82, $83, $84, $85, $86, $87, $c0, $c1, $c2, $c3, $c4, $c5, $c6, $c7
-            .byte $00, $01, $02, $03, $04, $05, $06, $07, $40, $41, $42, $43, $44, $45, $46, $47
-            .byte $80, $81, $82, $83, $84, $85, $86, $87, $c0, $c1, $c2, $c3, $c4, $c5, $c6, $c7
-            .byte $00, $01, $02, $03, $04, $05, $06, $07, $40, $41, $42, $43, $44, $45, $46, $47
-            .byte $80, $81, $82, $83, $84, $85, $86, $87, $c0, $c1, $c2, $c3, $c4, $c5, $c6, $c7
-            .byte $00, $01, $02, $03, $04, $05, $06, $07
-        }}
-    }
-
-}
-
-

examples/cmp/comparison_ifs_byte.p8

@@ -0,0 +1,109 @@
+%import c64textio
+%zeropage basicsafe
+
+
+main {
+
+    sub start()  {
+
+        byte v1
+        byte v2
+
+        v1 = 100
+        v2 = 127
+        if v1==v2
+            txt.print("error in 100==127!\n")
+        else
+            txt.print("ok: 100 not == 127\n")
+
+        if v1!=v2
+            txt.print("ok: 100 != 127\n")
+        else
+            txt.print("error in 100!=127!\n")
+
+        if v1<v2
+            txt.print("ok: 100 < 127\n")
+        else
+            txt.print("error in 100<127!\n")
+
+        if v1<=v2
+            txt.print("ok: 100 <= 127\n")
+        else
+            txt.print("error in 100<=127!\n")
+
+        if v1>v2
+            txt.print("error in 100>127!\n")
+        else
+            txt.print("ok: 100 is not >127\n")
+
+        if v1>=v2
+            txt.print("error in 100>=127!\n")
+        else
+            txt.print("ok: 100 is not >=127\n")
+
+
+        v1 = 125
+        v2 = 22
+        if v1==v2
+            txt.print("error in 125==22!\n")
+        else
+            txt.print("ok: 125 not == 22\n")
+
+        if v1!=v2
+            txt.print("ok: 125 != 22\n")
+        else
+            txt.print("error in 125!=22!\n")
+
+        if v1<v2
+            txt.print("error in 125<22!\n")
+        else
+            txt.print("ok: 125 is not < 22\n")
+
+        if v1<=v2
+            txt.print("error in 125<=22!\n")
+        else
+            txt.print("ok: 125 is not <= 22\n")
+
+        if v1>v2
+            txt.print("ok: 125 > 22\n")
+        else
+            txt.print("error in 125>22!\n")
+
+        if v1>=v2
+            txt.print("ok: 125 >= 22\n")
+        else
+            txt.print("error in 125>=22!\n")
+
+        v1 = 22
+        v2 = 22
+        if v1==v2
+            txt.print("ok: 22 == 22\n")
+        else
+            txt.print("error in 22==22!\n")
+
+        if v1!=v2
+            txt.print("error in 22!=22!\n")
+        else
+            txt.print("ok: 22 is not != 22\n")
+
+        if v1<v2
+            txt.print("error in 22<22!\n")
+        else
+            txt.print("ok: 22 is not < 22\n")
+
+        if v1<=v2
+            txt.print("ok: 22 <= 22\n")
+        else
+            txt.print("error in 22<=22!\n")
+
+        if v1>v2
+            txt.print("error in 22>22!\n")
+        else
+            txt.print("ok: 22 is not > 22\n")
+
+        if v1>=v2
+            txt.print("ok: 22 >= 22\n")
+        else
+            txt.print("error in 22>=22!\n")
+    }
+}

examples/cmp/comparison_ifs_float.p8

@@ -0,0 +1,109 @@
+%import c64textio
+%import c64flt
+%zeropage basicsafe
+
+main {
+
+    sub start()  {
+
+        float v1
+        float v2
+
+        v1 = 1.11
+        v2 = 699.99
+        if v1==v2
+            txt.print("error in 1.11==699.99!\n")
+        else
+            txt.print("ok: 1.11 not == 699.99\n")
+
+        if v1!=v2
+            txt.print("ok: 1.11 != 699.99\n")
+        else
+            txt.print("error in 1.11!=699.99!\n")
+
+        if v1<v2
+            txt.print("ok: 1.11 < 699.99\n")
+        else
+            txt.print("error in 1.11<699.99!\n")
+
+        if v1<=v2
+            txt.print("ok: 1.11 <= 699.99\n")
+        else
+            txt.print("error in 1.11<=699.99!\n")
+
+        if v1>v2
+            txt.print("error in 1.11>699.99!\n")
+        else
+            txt.print("ok: 1.11 is not >699.99\n")
+
+        if v1>=v2
+            txt.print("error in 1.11>=699.99!\n")
+        else
+            txt.print("ok: 1.11 is not >=699.99\n")
+
+
+        v1 = 555.5
+        v2 = -22.2
+        if v1==v2
+            txt.print("error in 555.5==-22.2!\n")
+        else
+            txt.print("ok: 555.5 not == -22.2\n")
+
+        if v1!=v2
+            txt.print("ok: 555.5 != -22.2\n")
+        else
+            txt.print("error in 555.5!=-22.2!\n")
+
+        if v1<v2
+            txt.print("error in 555.5<-22.2!\n")
+        else
+            txt.print("ok: 555.5 is not < -22.2\n")
+
+        if v1<=v2
+            txt.print("error in 555.5<=-22.2!\n")
+        else
+            txt.print("ok: 555.5 is not <= -22.2\n")
+
+        if v1>v2
+            txt.print("ok: 555.5 > -22.2\n")
+        else
+            txt.print("error in 555.5>-22.2!\n")
+
+        if v1>=v2
+            txt.print("ok: 555.5 >= -22.2\n")
+        else
+            txt.print("error in 555.5>=-22.2!\n")
+
+        v1 = -22.2
+        v2 = -22.2
+        if v1==v2
+            txt.print("ok: -22.2 == -22.2\n")
+        else
+            txt.print("error in -22.2==-22.2!\n")
+
+        if v1!=v2
+            txt.print("error in -22.2!=-22.2!\n")
+        else
+            txt.print("ok: -22.2 is not != -22.2\n")
+
+        if v1<v2
+            txt.print("error in -22.2<-22.2!\n")
+        else
+            txt.print("ok: -22.2 is not < -22.2\n")
+
+        if v1<=v2
+            txt.print("ok: -22.2 <= -22.2\n")
+        else
+            txt.print("error in -22.2<=-22.2!\n")
+
+        if v1>v2
+            txt.print("error in -22.2>-22.2!\n")
+        else
+            txt.print("ok: -22.2 is not > -22.2\n")
+
+        if v1>=v2
+            txt.print("ok: -22.2 >= -22.2\n")
+        else
+            txt.print("error in -22.2>=-22.2!\n")
+    }
+}

examples/cmp/comparison_ifs_ubyte.p8

@@ -0,0 +1,109 @@
+%import c64textio
+%zeropage basicsafe
+
+
+main {
+
+    sub start()  {
+
+        ubyte v1
+        ubyte v2
+
+        v1 = 100
+        v2 = 200
+        if v1==v2
+            txt.print("error in 100==200!\n")
+        else
+            txt.print("ok: 100 not == 200\n")
+
+        if v1!=v2
+            txt.print("ok: 100 != 200\n")
+        else
+            txt.print("error in 100!=200!\n")
+
+        if v1<v2
+            txt.print("ok: 100 < 200\n")
+        else
+            txt.print("error in 100<200!\n")
+
+        if v1<=v2
+            txt.print("ok: 100 <= 200\n")
+        else
+            txt.print("error in 100<=200!\n")
+
+        if v1>v2
+            txt.print("error in 100>200!\n")
+        else
+            txt.print("ok: 100 is not >200\n")
+
+        if v1>=v2
+            txt.print("error in 100>=200!\n")
+        else
+            txt.print("ok: 100 is not >=200\n")
+
+
+        v1 = 155
+        v2 = 22
+        if v1==v2
+            txt.print("error in 155==22!\n")
+        else
+            txt.print("ok: 155 not == 22\n")
+
+        if v1!=v2
+            txt.print("ok: 155 != 22\n")
+        else
+            txt.print("error in 155!=22!\n")
+
+        if v1<v2
+            txt.print("error in 155<22!\n")
+        else
+            txt.print("ok: 155 is not < 22\n")
+
+        if v1<=v2
+            txt.print("error in 155<=22!\n")
+        else
+            txt.print("ok: 155 is not <= 22\n")
+
+        if v1>v2
+            txt.print("ok: 155 > 22\n")
+        else
+            txt.print("error in 155>22!\n")
+
+        if v1>=v2
+            txt.print("ok: 155 >= 22\n")
+        else
+            txt.print("error in 155>=22!\n")
+
+        v1 = 22
+        v2 = 22
+        if v1==v2
+            txt.print("ok: 22 == 22\n")
+        else
+            txt.print("error in 22==22!\n")
+
+        if v1!=v2
+            txt.print("error in 22!=22!\n")
+        else
+            txt.print("ok: 22 is not != 22\n")
+
+        if v1<v2
+            txt.print("error in 22<22!\n")
+        else
+            txt.print("ok: 22 is not < 22\n")
+
+        if v1<=v2
+            txt.print("ok: 22 <= 22\n")
+        else
+            txt.print("error in 22<=22!\n")
+
+        if v1>v2
+            txt.print("error in 22>22!\n")
+        else
+            txt.print("ok: 22 is not > 22\n")
+
+        if v1>=v2
+            txt.print("ok: 22 >= 22\n")
+        else
+            txt.print("error in 22>=22!\n")
+    }
+}

examples/cmp/comparison_ifs_uword.p8

@@ -0,0 +1,109 @@
+%import c64textio
+%zeropage basicsafe
+
+
+main {
+
+    sub start()  {
+
+        uword v1
+        uword v2
+
+        v1 = 100
+        v2 = 64444
+        if v1==v2
+            txt.print("error in 100==64444!\n")
+        else
+            txt.print("ok: 100 not == 64444\n")
+
+        if v1!=v2
+            txt.print("ok: 100 != 64444\n")
+        else
+            txt.print("error in 100!=64444!\n")
+
+        if v1<v2
+            txt.print("ok: 100 < 64444\n")
+        else
+            txt.print("error in 100<64444!\n")
+
+        if v1<=v2
+            txt.print("ok: 100 <= 64444\n")
+        else
+            txt.print("error in 100<=64444!\n")
+
+        if v1>v2
+            txt.print("error in 100>64444!\n")
+        else
+            txt.print("ok: 100 is not >64444\n")
+
+        if v1>=v2
+            txt.print("error in 100>=64444!\n")
+        else
+            txt.print("ok: 100 is not >=64444\n")
+
+
+        v1 = 5555
+        v2 = 322
+        if v1==v2
+            txt.print("error in 5555==322!\n")
+        else
+            txt.print("ok: 5555 not == 322\n")
+
+        if v1!=v2
+            txt.print("ok: 5555 != 322\n")
+        else
+            txt.print("error in 5555!=322!\n")
+
+        if v1<v2
+            txt.print("error in 5555<322!\n")
+        else
+            txt.print("ok: 5555 is not < 322\n")
+
+        if v1<=v2
+            txt.print("error in 5555<=322!\n")
+        else
+            txt.print("ok: 5555 is not <= 322\n")
+
+        if v1>v2
+            txt.print("ok: 5555 > 322\n")
+        else
+            txt.print("error in 5555>322!\n")
+
+        if v1>=v2
+            txt.print("ok: 5555 >= 322\n")
+        else
+            txt.print("error in 5555>=322!\n")
+
+        v1 = 322
+        v2 = 322
+        if v1==v2
+            txt.print("ok: 322 == 322\n")
+        else
+            txt.print("error in 322==322!\n")
+
+        if v1!=v2
+            txt.print("error in 322!=322!\n")
+        else
+            txt.print("ok: 322 is not != 322\n")
+
+        if v1<v2
+            txt.print("error in 322<322!\n")
+        else
+            txt.print("ok: 322 is not < 322\n")
+
+        if v1<=v2
+            txt.print("ok: 322 <= 322\n")
+        else
+            txt.print("error in 322<=322!\n")
+
+        if v1>v2
+            txt.print("error in 322>322!\n")
+        else
+            txt.print("ok: 322 is not > 322\n")
+
+        if v1>=v2
+            txt.print("ok: 322 >= 322\n")
+        else
+            txt.print("error in 322>=322!\n")
+    }
+}

examples/cmp/comparison_ifs_word.p8

@@ -0,0 +1,141 @@
+%import c64textio
+%zeropage basicsafe
+
+
+main {
+
+    sub start()  {
+
+        word v1
+        word v2
+
+        v1 = 100
+        v2 = 30333
+        if v1==v2
+            txt.print("error in 100==30333!\n")
+        else
+            txt.print("ok: 100 not == 30333\n")
+
+        if v1!=v2
+            txt.print("ok: 100 != 30333\n")
+        else
+            txt.print("error in 100!=30333!\n")
+
+        if v1<v2
+            txt.print("ok: 100 < 30333\n")
+        else
+            txt.print("error in 100<30333!\n")
+
+        if v1<=v2
+            txt.print("ok: 100 <= 30333\n")
+        else
+            txt.print("error in 100<=30333!\n")
+
+        if v1>v2
+            txt.print("error in 100>30333!\n")
+        else
+            txt.print("ok: 100 is not >30333\n")
+
+        if v1>=v2
+            txt.print("error in 100>=30333!\n")
+        else
+            txt.print("ok: 100 is not >=30333\n")
+
+
+        v1 = 125
+        v2 = -222
+        if v1==v2
+            txt.print("error in 125==-222!\n")
+        else
+            txt.print("ok: 125 not == -222\n")
+
+        if v1!=v2
+            txt.print("ok: 125 != -222\n")
+        else
+            txt.print("error in 125!=-222!\n")
+
+        if v1<v2
+            txt.print("error in 125<-222!\n")
+        else
+            txt.print("ok: 125 is not < -222\n")
+
+        if v1<=v2
+            txt.print("error in 125<=-222!\n")
+        else
+            txt.print("ok: 125 is not <= -222\n")
+
+        if v1>v2
+            txt.print("ok: 125 > -222\n")
+        else
+            txt.print("error in 125>-222!\n")
+
+        if v1>=v2
+            txt.print("ok: 125 >= -222\n")
+        else
+            txt.print("error in 125>=-222!\n")
+
+        v1 = -222
+        v2 = -222
+        if v1==v2
+            txt.print("ok: -222 == -222\n")
+        else
+            txt.print("error in -222==-222!\n")
+
+        if v1!=v2
+            txt.print("error in -222!=-222!\n")
+        else
+            txt.print("ok: -222 is not != -222\n")
+
+        if v1<v2
+            txt.print("error in -222<-222!\n")
+        else
+            txt.print("ok: -222 is not < -222\n")
+
+        if v1<=v2
+            txt.print("ok: -222 <= -222\n")
+        else
+            txt.print("error in -222<=-222!\n")
+
+        if v1>v2
+            txt.print("error in -222>-222!\n")
+        else
+            txt.print("ok: -222 is not > -222\n")
+
+        if v1>=v2
+            txt.print("ok: -222 >= -222\n")
+        else
+            txt.print("error in -222>=-222!\n")
+
+        v1 = 1000
+        v2 = 1000
+        if v1==v2
+            txt.print("ok: 1000 == 1000\n")
+        else
+            txt.print("error in 1000==1000!\n")
+
+        if v1!=v2
+            txt.print("error in 1000!=1000!\n")
+        else
+            txt.print("ok: 1000 is not != 1000\n")
+
+        if v1<v2
+            txt.print("error in 1000<1000!\n")
+        else
+            txt.print("ok: 1000 is not < 1000\n")
+
+        if v1<=v2
+            txt.print("ok: 1000 <= 1000\n")
+        else
+            txt.print("error in 1000<=1000!\n")
+
+        if v1>v2
+            txt.print("error in 1000>1000!\n")
+        else
+            txt.print("ok: 1000 is not > 1000\n")
+
+        if v1>=v2
+            txt.print("ok: 1000 >= 1000\n")
+        else
+            txt.print("error in 1000>=1000!\n")
+    }
+}

examples/cmp/comparisons_byte.p8

@@ -1,4 +1,4 @@
-%import c64utils
+%import c64textio
 %zeropage basicsafe
 
 main {
@@ -9,7 +9,7 @@ main {
         byte v2
         ubyte cr
 
-        c64scr.print("signed byte ")
+        txt.print("signed byte ")
 
         cr=v1==v2
         cr=v1==v2
@@ -39,52 +39,52 @@ main {
         ; comparisons:
         v1=-20
         v2=125
-        c64scr.print("v1=-20, v2=125\n")
+        txt.print("v1=-20, v2=125\n")
         compare()
 
         v1=80
         v2=80
-        c64scr.print("v1 = v2 = 80\n")
+        txt.print("v1 = v2 = 80\n")
         compare()
 
         v1=20
         v2=-111
-        c64scr.print("v1=20, v2=-111\n")
+        txt.print("v1=20, v2=-111\n")
         compare()
 
         return
 
         sub compare() {
-        c64scr.print("  ==  !=  <   >   <=  >=\n")
+        txt.print("  ==  !=  <   >   <=  >=\n")
 
         if v1==v2
-            c64scr.print("  Q ")
+            txt.print("  Q ")
         else
-            c64scr.print("  . ")
+            txt.print("  . ")
         if v1!=v2
-            c64scr.print("  Q ")
+            txt.print("  Q ")
         else
-            c64scr.print("  . ")
+            txt.print("  . ")
 
         if v1<v2
-            c64scr.print("  Q ")
+            txt.print("  Q ")
         else
-            c64scr.print("  . ")
+            txt.print("  . ")
 
         if v1>v2
-            c64scr.print("  Q ")
+            txt.print("  Q ")
         else
-            c64scr.print("  . ")
+            txt.print("  . ")
 
         if v1<=v2
-            c64scr.print("  Q ")
+            txt.print("  Q ")
         else
-            c64scr.print("  . ")
+            txt.print("  . ")
 
         if v1>=v2
-            c64scr.print("  Q ")
+            txt.print("  Q ")
         else
-            c64scr.print("  . ")
+            txt.print("  . ")
         c64.CHROUT('\n')
 
     }

examples/cmp/comparisons_float.p8

@@ -1,4 +1,4 @@
-%import c64utils
+%import c64textio
 %import c64flt
 %zeropage basicsafe
 
@@ -10,7 +10,7 @@ main {
         float v2
         ubyte cr
 
-        c64scr.print("floating point ")
+        txt.print("floating point ")
 
         cr=v1==v2
         cr=v1==v2
@@ -40,67 +40,67 @@ main {
         ; comparisons:
         v1=20
         v2=666.66
-        c64scr.print("v1=20, v2=666.66\n")
+        txt.print("v1=20, v2=666.66\n")
         compare()
 
         v1=-20
         v2=666.66
-        c64scr.print("v1=-20, v2=666.66\n")
+        txt.print("v1=-20, v2=666.66\n")
         compare()
 
         v1=666.66
         v2=555.55
-        c64scr.print("v1=666.66, v2=555.55\n")
+        txt.print("v1=666.66, v2=555.55\n")
         compare()
 
         v1=3.1415
         v2=-3.1415
-        c64scr.print("v1 = 3.1415, v2 = -3.1415\n")
+        txt.print("v1 = 3.1415, v2 = -3.1415\n")
         compare()
 
         v1=3.1415
         v2=3.1415
-        c64scr.print("v1 = v2 = 3.1415\n")
+        txt.print("v1 = v2 = 3.1415\n")
         compare()
 
         v1=0
         v2=0
-        c64scr.print("v1 = v2 = 0\n")
+        txt.print("v1 = v2 = 0\n")
         compare()
 
         return
 
         sub compare() {
-        c64scr.print("  ==  !=  <   >   <=  >=\n")
+        txt.print("  ==  !=  <   >   <=  >=\n")
 
         if v1==v2
-            c64scr.print("  Q ")
+            txt.print("  Q ")
         else
-            c64scr.print("  . ")
+            txt.print("  . ")
         if v1!=v2
-            c64scr.print("  Q ")
+            txt.print("  Q ")
         else
-            c64scr.print("  . ")
+            txt.print("  . ")
 
         if v1<v2
-            c64scr.print("  Q ")
+            txt.print("  Q ")
         else
-            c64scr.print("  . ")
+            txt.print("  . ")
 
         if v1>v2
-            c64scr.print("  Q ")
+            txt.print("  Q ")
         else
-            c64scr.print("  . ")
+            txt.print("  . ")
 
         if v1<=v2
-            c64scr.print("  Q ")
+            txt.print("  Q ")
         else
-            c64scr.print("  . ")
+            txt.print("  . ")
 
         if v1>=v2
-            c64scr.print("  Q ")
+            txt.print("  Q ")
         else
-            c64scr.print("  . ")
+            txt.print("  . ")
         c64.CHROUT('\n')
 
     }

examples/cmp/comparisons_ubyte.p8

@@ -1,4 +1,4 @@
-%import c64utils
+%import c64textio
 %zeropage basicsafe
 
 main {
@@ -9,7 +9,7 @@ main {
         ubyte v2
         ubyte cr
 
-        c64scr.print("unsigned byte ")
+        txt.print("unsigned byte ")
 
         cr=v1==v2
         cr=v1==v2
@@ -39,52 +39,52 @@ main {
         ; comparisons:
         v1=20
         v2=199
-        c64scr.print("v1=20, v2=199\n")
+        txt.print("v1=20, v2=199\n")
         compare()
 
         v1=80
         v2=80
-        c64scr.print("v1 = v2 = 80\n")
+        txt.print("v1 = v2 = 80\n")
         compare()
 
         v1=220
         v2=10
-        c64scr.print("v1=220, v2=10\n")
+        txt.print("v1=220, v2=10\n")
         compare()
 
         return
 
         sub compare() {
-        c64scr.print("  ==  !=  <   >   <=  >=\n")
+        txt.print("  ==  !=  <   >   <=  >=\n")
 
         if v1==v2
-            c64scr.print("  Q ")
+            txt.print("  Q ")
         else
-            c64scr.print("  . ")
+            txt.print("  . ")
         if v1!=v2
-            c64scr.print("  Q ")
+            txt.print("  Q ")
         else
-            c64scr.print("  . ")
+            txt.print("  . ")
 
         if v1<v2
-            c64scr.print("  Q ")
+            txt.print("  Q ")
         else
-            c64scr.print("  . ")
+            txt.print("  . ")
 
         if v1>v2
-            c64scr.print("  Q ")
+            txt.print("  Q ")
         else
-            c64scr.print("  . ")
+            txt.print("  . ")
 
         if v1<=v2
-            c64scr.print("  Q ")
+            txt.print("  Q ")
         else
-            c64scr.print("  . ")
+            txt.print("  . ")
 
         if v1>=v2
-            c64scr.print("  Q ")
+            txt.print("  Q ")
         else
-            c64scr.print("  . ")
+            txt.print("  . ")
         c64.CHROUT('\n')
 
     }

examples/cmp/comparisons_uword.p8

@@ -1,4 +1,4 @@
-%import c64utils
+%import c64textio
 %zeropage basicsafe
 
 main {
@@ -9,7 +9,7 @@ main {
         uword v2
         ubyte cr
 
-        c64scr.print("unsigned word ")
+        txt.print("unsigned word ")
 
         cr=v1==v2
         cr=v1==v2
@@ -39,82 +39,82 @@ main {
         ; comparisons:
         v1=20
         v2=$00aa
-        c64scr.print("v1=20, v2=$00aa\n")
+        txt.print("v1=20, v2=$00aa\n")
         compare()
 
         v1=20
         v2=$ea00
-        c64scr.print("v1=20, v2=$ea00\n")
+        txt.print("v1=20, v2=$ea00\n")
         compare()
 
         v1=$c400
         v2=$22
-        c64scr.print("v1=$c400, v2=$22\n")
+        txt.print("v1=$c400, v2=$22\n")
         compare()
 
         v1=$c400
         v2=$2a00
-        c64scr.print("v1=$c400, v2=$2a00\n")
+        txt.print("v1=$c400, v2=$2a00\n")
         compare()
 
         v1=$c433
         v2=$2a00
-        c64scr.print("v1=$c433, v2=$2a00\n")
+        txt.print("v1=$c433, v2=$2a00\n")
         compare()
 
         v1=$c433
         v2=$2aff
-        c64scr.print("v1=$c433, v2=$2aff\n")
+        txt.print("v1=$c433, v2=$2aff\n")
         compare()
 
         v1=$aabb
         v2=$aabb
-        c64scr.print("v1 = v2 = aabb\n")
+        txt.print("v1 = v2 = aabb\n")
         compare()
 
         v1=$aa00
         v2=$aa00
-        c64scr.print("v1 = v2 = aa00\n")
+        txt.print("v1 = v2 = aa00\n")
         compare()
 
         v1=$aa
         v2=$aa
-        c64scr.print("v1 = v2 = aa\n")
+        txt.print("v1 = v2 = aa\n")
         compare()
 
         return
 
         sub compare() {
-        c64scr.print("  ==  !=  <   >   <=  >=\n")
+        txt.print("  ==  !=  <   >   <=  >=\n")
 
         if v1==v2
-            c64scr.print("  Q ")
+            txt.print("  Q ")
         else
-            c64scr.print("  . ")
+            txt.print("  . ")
         if v1!=v2
-            c64scr.print("  Q ")
+            txt.print("  Q ")
         else
-            c64scr.print("  . ")
+            txt.print("  . ")
 
         if v1<v2
-            c64scr.print("  Q ")
+            txt.print("  Q ")
         else
-            c64scr.print("  . ")
+            txt.print("  . ")
 
         if v1>v2
-            c64scr.print("  Q ")
+            txt.print("  Q ")
         else
-            c64scr.print("  . ")
+            txt.print("  . ")
 
         if v1<=v2
-            c64scr.print("  Q ")
+            txt.print("  Q ")
         else
-            c64scr.print("  . ")
+            txt.print("  . ")
 
         if v1>=v2
-            c64scr.print("  Q ")
+            txt.print("  Q ")
         else
-            c64scr.print("  . ")
+            txt.print("  . ")
         c64.CHROUT('\n')
 
     }

examples/cmp/comparisons_word.p8

@@ -1,4 +1,4 @@
-%import c64utils
+%import c64textio
 %zeropage basicsafe
 
 main {
@@ -9,7 +9,7 @@ main {
         word v2
         ubyte cr
 
-        c64scr.print("signed word ")
+        txt.print("signed word ")
 
         cr=v1==v2
         cr=v1==v2
@@ -39,118 +39,118 @@ main {
         ; comparisons:
         v1=20
         v2=$00aa
-        c64scr.print("v1=20, v2=$00aa\n")
+        txt.print("v1=20, v2=$00aa\n")
         compare()
 
         v1=20
         v2=$7a00
-        c64scr.print("v1=20, v2=$7a00\n")
+        txt.print("v1=20, v2=$7a00\n")
         compare()
 
         v1=$7400
         v2=$22
-        c64scr.print("v1=$7400, v2=$22\n")
+        txt.print("v1=$7400, v2=$22\n")
         compare()
 
         v1=$7400
         v2=$2a00
-        c64scr.print("v1=$7400, v2=$2a00\n")
+        txt.print("v1=$7400, v2=$2a00\n")
         compare()
 
         v1=$7433
         v2=$2a00
-        c64scr.print("v1=$7433, v2=$2a00\n")
+        txt.print("v1=$7433, v2=$2a00\n")
         compare()
 
         v1=$7433
         v2=$2aff
-        c64scr.print("v1=$7433, v2=$2aff\n")
+        txt.print("v1=$7433, v2=$2aff\n")
         compare()
 
         ;  with negative numbers:
         v1=-512
         v2=$00aa
-        c64scr.print("v1=-512, v2=$00aa\n")
+        txt.print("v1=-512, v2=$00aa\n")
         compare()
 
         v1=-512
         v2=$7a00
-        c64scr.print("v1=-512, v2=$7a00\n")
+        txt.print("v1=-512, v2=$7a00\n")
         compare()
 
         v1=$7400
         v2=-512
-        c64scr.print("v1=$7400, v2=-512\n")
+        txt.print("v1=$7400, v2=-512\n")
         compare()
 
         v1=-20000
         v2=-1000
-        c64scr.print("v1=-20000, v2=-1000\n")
+        txt.print("v1=-20000, v2=-1000\n")
         compare()
 
         v1=-1000
         v2=-20000
-        c64scr.print("v1=-1000, v2=-20000\n")
+        txt.print("v1=-1000, v2=-20000\n")
         compare()
 
         v1=-1
         v2=32767
-        c64scr.print("v1=-1, v2=32767\n")
+        txt.print("v1=-1, v2=32767\n")
         compare()
 
         v1=32767
         v2=-1
-        c64scr.print("v1=32767, v2=-1\n")
+        txt.print("v1=32767, v2=-1\n")
         compare()
 
         v1=$7abb
         v2=$7abb
-        c64scr.print("v1 = v2 = 7abb\n")
+        txt.print("v1 = v2 = 7abb\n")
         compare()
 
         v1=$7a00
         v2=$7a00
-        c64scr.print("v1 = v2 = 7a00\n")
+        txt.print("v1 = v2 = 7a00\n")
         compare()
 
         v1=$aa
         v2=$aa
-        c64scr.print("v1 = v2 = aa\n")
+        txt.print("v1 = v2 = aa\n")
         compare()
 
         return
 
         sub compare() {
-        c64scr.print("  ==  !=  <   >   <=  >=\n")
+        txt.print("  ==  !=  <   >   <=  >=\n")
 
         if v1==v2
-            c64scr.print("  Q ")
+            txt.print("  Q ")
         else
-            c64scr.print("  . ")
+            txt.print("  . ")
         if v1!=v2
-            c64scr.print("  Q ")
+            txt.print("  Q ")
         else
-            c64scr.print("  . ")
+            txt.print("  . ")
 
         if v1<v2
-            c64scr.print("  Q ")
+            txt.print("  Q ")
         else
-            c64scr.print("  . ")
+            txt.print("  . ")
 
         if v1>v2
-            c64scr.print("  Q ")
+            txt.print("  Q ")
         else
-            c64scr.print("  . ")
+            txt.print("  . ")
 
         if v1<=v2
-            c64scr.print("  Q ")
+            txt.print("  Q ")
         else
-            c64scr.print("  . ")
+            txt.print("  . ")
 
         if v1>=v2
-            c64scr.print("  Q ")
+            txt.print("  Q ")
         else
-            c64scr.print("  . ")
+            txt.print("  . ")
         c64.CHROUT('\n')
 
     }

examples/comparison_ifs_byte.p8

@@ -1,109 +0,0 @@
-%import c64utils
-%zeropage basicsafe
-
-
-main {
-
-    sub start()  {
-
-        byte v1
-        byte v2
-
-        v1 = 100
-        v2 = 127
-        if v1==v2
-            c64scr.print("error in 100==127!\n")
-        else
-            c64scr.print("ok: 100 not == 127\n")
-
-        if v1!=v2
-            c64scr.print("ok: 100 != 127\n")
-        else
-            c64scr.print("error in 100!=127!\n")
-
-        if v1<v2
-            c64scr.print("ok: 100 < 127\n")
-        else
-            c64scr.print("error in 100<127!\n")
-
-        if v1<=v2
-            c64scr.print("ok: 100 <= 127\n")
-        else
-            c64scr.print("error in 100<=127!\n")
-
-        if v1>v2
-            c64scr.print("error in 100>127!\n")
-        else
-            c64scr.print("ok: 100 is not >127\n")
-
-        if v1>=v2
-            c64scr.print("error in 100>=127!\n")
-        else
-            c64scr.print("ok: 100 is not >=127\n")
-
-
-        v1 = 125
-        v2 = 22
-        if v1==v2
-            c64scr.print("error in 125==22!\n")
-        else
-            c64scr.print("ok: 125 not == 22\n")
-
-        if v1!=v2
-            c64scr.print("ok: 125 != 22\n")
-        else
-            c64scr.print("error in 125!=22!\n")
-
-        if v1<v2
-            c64scr.print("error in 125<22!\n")
-        else
-            c64scr.print("ok: 125 is not < 22\n")
-
-        if v1<=v2
-            c64scr.print("error in 125<=22!\n")
-        else
-            c64scr.print("ok: 125 is not <= 22\n")
-
-        if v1>v2
-            c64scr.print("ok: 125 > 22\n")
-        else
-            c64scr.print("error in 125>22!\n")
-
-        if v1>=v2
-            c64scr.print("ok: 125 >= 22\n")
-        else
-            c64scr.print("error in 125>=22!\n")
-
-        v1 = 22
-        v2 = 22
-        if v1==v2
-            c64scr.print("ok: 22 == 22\n")
-        else
-            c64scr.print("error in 22==22!\n")
-
-        if v1!=v2
-            c64scr.print("error in 22!=22!\n")
-        else
-            c64scr.print("ok: 22 is not != 22\n")
-
-        if v1<v2
-            c64scr.print("error in 22<22!\n")
-        else
-            c64scr.print("ok: 22 is not < 22\n")
-
-        if v1<=v2
-            c64scr.print("ok: 22 <= 22\n")
-        else
-            c64scr.print("error in 22<=22!\n")
-
-        if v1>v2
-            c64scr.print("error in 22>22!\n")
-        else
-            c64scr.print("ok: 22 is not > 22\n")
-
-        if v1>=v2
-            c64scr.print("ok: 22 >= 22\n")
-        else
-            c64scr.print("error in 22>=22!\n")
-    }
-}

examples/comparison_ifs_float.p8

@@ -1,109 +0,0 @@
-%import c64utils
-%import c64flt
-%zeropage basicsafe
-
-main {
-
-    sub start()  {
-
-        float v1
-        float v2
-
-        v1 = 1.11
-        v2 = 699.99
-        if v1==v2
-            c64scr.print("error in 1.11==699.99!\n")
-        else
-            c64scr.print("ok: 1.11 not == 699.99\n")
-
-        if v1!=v2
-            c64scr.print("ok: 1.11 != 699.99\n")
-        else
-            c64scr.print("error in 1.11!=699.99!\n")
-
-        if v1<v2
-            c64scr.print("ok: 1.11 < 699.99\n")
-        else
-            c64scr.print("error in 1.11<699.99!\n")
-
-        if v1<=v2
-            c64scr.print("ok: 1.11 <= 699.99\n")
-        else
-            c64scr.print("error in 1.11<=699.99!\n")
-
-        if v1>v2
-            c64scr.print("error in 1.11>699.99!\n")
-        else
-            c64scr.print("ok: 1.11 is not >699.99\n")
-
-        if v1>=v2
-            c64scr.print("error in 1.11>=699.99!\n")
-        else
-            c64scr.print("ok: 1.11 is not >=699.99\n")
-
-
-        v1 = 555.5
-        v2 = -22.2
-        if v1==v2
-            c64scr.print("error in 555.5==-22.2!\n")
-        else
-            c64scr.print("ok: 555.5 not == -22.2\n")
-
-        if v1!=v2
-            c64scr.print("ok: 555.5 != -22.2\n")
-        else
-            c64scr.print("error in 555.5!=-22.2!\n")
-
-        if v1<v2
-            c64scr.print("error in 555.5<-22.2!\n")
-        else
-            c64scr.print("ok: 555.5 is not < -22.2\n")
-
-        if v1<=v2
-            c64scr.print("error in 555.5<=-22.2!\n")
-        else
-            c64scr.print("ok: 555.5 is not <= -22.2\n")
-
-        if v1>v2
-            c64scr.print("ok: 555.5 > -22.2\n")
-        else
-            c64scr.print("error in 555.5>-22.2!\n")
-
-        if v1>=v2
-            c64scr.print("ok: 555.5 >= -22.2\n")
-        else
-            c64scr.print("error in 555.5>=-22.2!\n")
-
-        v1 = -22.2
-        v2 = -22.2
-        if v1==v2
-            c64scr.print("ok: -22.2 == -22.2\n")
-        else
-            c64scr.print("error in -22.2==-22.2!\n")
-
-        if v1!=v2
-            c64scr.print("error in -22.2!=-22.2!\n")
-        else
-            c64scr.print("ok: -22.2 is not != -22.2\n")
-
-        if v1<v2
-            c64scr.print("error in -22.2<-22.2!\n")
-        else
-            c64scr.print("ok: -22.2 is not < -22.2\n")
-
-        if v1<=v2
-            c64scr.print("ok: -22.2 <= -22.2\n")
-        else
-            c64scr.print("error in -22.2<=-22.2!\n")
-
-        if v1>v2
-            c64scr.print("error in -22.2>-22.2!\n")
-        else
-            c64scr.print("ok: -22.2 is not > -22.2\n")
-
-        if v1>=v2
-            c64scr.print("ok: -22.2 >= -22.2\n")
-        else
-            c64scr.print("error in -22.2>=-22.2!\n")
-    }
-}

examples/comparison_ifs_ubyte.p8

@@ -1,109 +0,0 @@
-%import c64utils
-%zeropage basicsafe
-
-
-main {
-
-    sub start()  {
-
-        ubyte v1
-        ubyte v2
-
-        v1 = 100
-        v2 = 200
-        if v1==v2
-            c64scr.print("error in 100==200!\n")
-        else
-            c64scr.print("ok: 100 not == 200\n")
-
-        if v1!=v2
-            c64scr.print("ok: 100 != 200\n")
-        else
-            c64scr.print("error in 100!=200!\n")
-
-        if v1<v2
-            c64scr.print("ok: 100 < 200\n")
-        else
-            c64scr.print("error in 100<200!\n")
-
-        if v1<=v2
-            c64scr.print("ok: 100 <= 200\n")
-        else
-            c64scr.print("error in 100<=200!\n")
-
-        if v1>v2
-            c64scr.print("error in 100>200!\n")
-        else
-            c64scr.print("ok: 100 is not >200\n")
-
-        if v1>=v2
-            c64scr.print("error in 100>=200!\n")
-        else
-            c64scr.print("ok: 100 is not >=200\n")
-
-
-        v1 = 155
-        v2 = 22
-        if v1==v2
-            c64scr.print("error in 155==22!\n")
-        else
-            c64scr.print("ok: 155 not == 22\n")
-
-        if v1!=v2
-            c64scr.print("ok: 155 != 22\n")
-        else
-            c64scr.print("error in 155!=22!\n")
-
-        if v1<v2
-            c64scr.print("error in 155<22!\n")
-        else
-            c64scr.print("ok: 155 is not < 22\n")
-
-        if v1<=v2
-            c64scr.print("error in 155<=22!\n")
-        else
-            c64scr.print("ok: 155 is not <= 22\n")
-
-        if v1>v2
-            c64scr.print("ok: 155 > 22\n")
-        else
-            c64scr.print("error in 155>22!\n")
-
-        if v1>=v2
-            c64scr.print("ok: 155 >= 22\n")
-        else
-            c64scr.print("error in 155>=22!\n")
-
-        v1 = 22
-        v2 = 22
-        if v1==v2
-            c64scr.print("ok: 22 == 22\n")
-        else
-            c64scr.print("error in 22==22!\n")
-
-        if v1!=v2
-            c64scr.print("error in 22!=22!\n")
-        else
-            c64scr.print("ok: 22 is not != 22\n")
-
-        if v1<v2
-            c64scr.print("error in 22<22!\n")
-        else
-            c64scr.print("ok: 22 is not < 22\n")
-
-        if v1<=v2
-            c64scr.print("ok: 22 <= 22\n")
-        else
-            c64scr.print("error in 22<=22!\n")
-
-        if v1>v2
-            c64scr.print("error in 22>22!\n")
-        else
-            c64scr.print("ok: 22 is not > 22\n")
-
-        if v1>=v2
-            c64scr.print("ok: 22 >= 22\n")
-        else
-            c64scr.print("error in 22>=22!\n")
-    }
-}

examples/comparison_ifs_uword.p8

@@ -1,109 +0,0 @@
-%import c64utils
-%zeropage basicsafe
-
-
-main {
-
-    sub start()  {
-
-        uword v1
-        uword v2
-
-        v1 = 100
-        v2 = 64444
-        if v1==v2
-            c64scr.print("error in 100==64444!\n")
-        else
-            c64scr.print("ok: 100 not == 64444\n")
-
-        if v1!=v2
-            c64scr.print("ok: 100 != 64444\n")
-        else
-            c64scr.print("error in 100!=64444!\n")
-
-        if v1<v2
-            c64scr.print("ok: 100 < 64444\n")
-        else
-            c64scr.print("error in 100<64444!\n")
-
-        if v1<=v2
-            c64scr.print("ok: 100 <= 64444\n")
-        else
-            c64scr.print("error in 100<=64444!\n")
-
-        if v1>v2
-            c64scr.print("error in 100>64444!\n")
-        else
-            c64scr.print("ok: 100 is not >64444\n")
-
-        if v1>=v2
-            c64scr.print("error in 100>=64444!\n")
-        else
-            c64scr.print("ok: 100 is not >=64444\n")
-
-
-        v1 = 5555
-        v2 = 322
-        if v1==v2
-            c64scr.print("error in 5555==322!\n")
-        else
-            c64scr.print("ok: 5555 not == 322\n")
-
-        if v1!=v2
-            c64scr.print("ok: 5555 != 322\n")
-        else
-            c64scr.print("error in 5555!=322!\n")
-
-        if v1<v2
-            c64scr.print("error in 5555<322!\n")
-        else
-            c64scr.print("ok: 5555 is not < 322\n")
-
-        if v1<=v2
-            c64scr.print("error in 5555<=322!\n")
-        else
-            c64scr.print("ok: 5555 is not <= 322\n")
-
-        if v1>v2
-            c64scr.print("ok: 5555 > 322\n")
-        else
-            c64scr.print("error in 5555>322!\n")
-
-        if v1>=v2
-            c64scr.print("ok: 5555 >= 322\n")
-        else
-            c64scr.print("error in 5555>=322!\n")
-
-        v1 = 322
-        v2 = 322
-        if v1==v2
-            c64scr.print("ok: 322 == 322\n")
-        else
-            c64scr.print("error in 322==322!\n")
-
-        if v1!=v2
-            c64scr.print("error in 322!=322!\n")
-        else
-            c64scr.print("ok: 322 is not != 322\n")
-
-        if v1<v2
-            c64scr.print("error in 322<322!\n")
-        else
-            c64scr.print("ok: 322 is not < 322\n")
-
-        if v1<=v2
-            c64scr.print("ok: 322 <= 322\n")
-        else
-            c64scr.print("error in 322<=322!\n")
-
-        if v1>v2
-            c64scr.print("error in 322>322!\n")
-        else
-            c64scr.print("ok: 322 is not > 322\n")
-
-        if v1>=v2
-            c64scr.print("ok: 322 >= 322\n")
-        else
-            c64scr.print("error in 322>=322!\n")
-    }
-}

examples/comparison_ifs_word.p8

@@ -1,141 +0,0 @@
-%import c64utils
-%zeropage basicsafe
-
-
-main {
-
-    sub start()  {
-
-        word v1
-        word v2
-
-        v1 = 100
-        v2 = 30333
-        if v1==v2
-            c64scr.print("error in 100==30333!\n")
-        else
-            c64scr.print("ok: 100 not == 30333\n")
-
-        if v1!=v2
-            c64scr.print("ok: 100 != 30333\n")
-        else
-            c64scr.print("error in 100!=30333!\n")
-
-        if v1<v2
-            c64scr.print("ok: 100 < 30333\n")
-        else
-            c64scr.print("error in 100<30333!\n")
-
-        if v1<=v2
-            c64scr.print("ok: 100 <= 30333\n")
-        else
-            c64scr.print("error in 100<=30333!\n")
-
-        if v1>v2
-            c64scr.print("error in 100>30333!\n")
-        else
-            c64scr.print("ok: 100 is not >30333\n")
-
-        if v1>=v2
-            c64scr.print("error in 100>=30333!\n")
-        else
-            c64scr.print("ok: 100 is not >=30333\n")
-
-
-        v1 = 125
-        v2 = -222
-        if v1==v2
-            c64scr.print("error in 125==-222!\n")
-        else
-            c64scr.print("ok: 125 not == -222\n")
-
-        if v1!=v2
-            c64scr.print("ok: 125 != -222\n")
-        else
-            c64scr.print("error in 125!=-222!\n")
-
-        if v1<v2
-            c64scr.print("error in 125<-222!\n")
-        else
-            c64scr.print("ok: 125 is not < -222\n")
-
-        if v1<=v2
-            c64scr.print("error in 125<=-222!\n")
-        else
-            c64scr.print("ok: 125 is not <= -222\n")
-
-        if v1>v2
-            c64scr.print("ok: 125 > -222\n")
-        else
-            c64scr.print("error in 125>-222!\n")
-
-        if v1>=v2
-            c64scr.print("ok: 125 >= -222\n")
-        else
-            c64scr.print("error in 125>=-222!\n")
-
-        v1 = -222
-        v2 = -222
-        if v1==v2
-            c64scr.print("ok: -222 == -222\n")
-        else
-            c64scr.print("error in -222==-222!\n")
-
-        if v1!=v2
-            c64scr.print("error in -222!=-222!\n")
-        else
-            c64scr.print("ok: -222 is not != -222\n")
-
-        if v1<v2
-            c64scr.print("error in -222<-222!\n")
-        else
-            c64scr.print("ok: -222 is not < -222\n")
-
-        if v1<=v2
-            c64scr.print("ok: -222 <= -222\n")
-        else
-            c64scr.print("error in -222<=-222!\n")
-
-        if v1>v2
-            c64scr.print("error in -222>-222!\n")
-        else
-            c64scr.print("ok: -222 is not > -222\n")
-
-        if v1>=v2
-            c64scr.print("ok: -222 >= -222\n")
-        else
-            c64scr.print("error in -222>=-222!\n")
-
-        v1 = 1000
-        v2 = 1000
-        if v1==v2
-            c64scr.print("ok: 1000 == 1000\n")
-        else
-            c64scr.print("error in 1000==1000!\n")
-
-        if v1!=v2
-            c64scr.print("error in 1000!=1000!\n")
-        else
-            c64scr.print("ok: 1000 is not != 1000\n")
-
-        if v1<v2
-            c64scr.print("error in 1000<1000!\n")
-        else
-            c64scr.print("ok: 1000 is not < 1000\n")
-
-        if v1<=v2
-            c64scr.print("ok: 1000 <= 1000\n")
-        else
-            c64scr.print("error in 1000<=1000!\n")
-
-        if v1>v2
-            c64scr.print("error in 1000>1000!\n")
-        else
-            c64scr.print("ok: 1000 is not > 1000\n")
-
-        if v1>=v2
-            c64scr.print("ok: 1000 >= 1000\n")
-        else
-            c64scr.print("error in 1000>=1000!\n")
-    }
-}