Added test demonstrating problem with using $ff as temporary zp in fragments.

src/main/fragment/cache/fragment-cache-csg65ce02.asm

@@ -1,4 +1,4 @@
-//KICKC FRAGMENT CACHE df9b88c62 df9b8b138
+//KICKC FRAGMENT CACHE e65dd24b5 e65dd4993
 //FRAGMENT vbuzz=vbuc1
 ldz #{c1}
 //FRAGMENT vbuzz_lt_vbuc1_then_la1

src/main/fragment/cache/fragment-cache-mega45gs02.asm

@@ -1,4 +1,4 @@
-//KICKC FRAGMENT CACHE df9b88c62 df9b8b138
+//KICKC FRAGMENT CACHE e65dd24b5 e65dd4993
 //FRAGMENT vbuz1=vbuc1
 ldz #{c1}
 stz {z1}

src/main/fragment/cache/fragment-cache-mos6502.asm

@@ -1,4 +1,4 @@
-//KICKC FRAGMENT CACHE df9b88c62 df9b8b138
+//KICKC FRAGMENT CACHE e65dd24b5 e65dd4993
 //FRAGMENT vbuz1=vbuc1
 lda #{c1}
 sta {z1}

src/main/fragment/cache/fragment-cache-mos6502x.asm

@@ -1,4 +1,4 @@
-//KICKC FRAGMENT CACHE df9b88c62 df9b8b138
+//KICKC FRAGMENT CACHE e65dd24b5 e65dd4993
 //FRAGMENT vbuz1=vbuc1
 lda #{c1}
 sta {z1}
@@ -8935,6 +8935,16 @@ bcc {la1}
 lda {c1}
 cmp #{c2}
 bcs {la1}
+//FRAGMENT _deref_pbum1=_inc__deref_pbum1
+ldy {m1}
+sty $fe
+ldy {m1}+1
+sty $ff
+ldy #0
+lda ($fe),y
+clc
+adc #1
+sta ($fe),y
 //FRAGMENT pwuz1=pwuc1
 lda #<{c1}
 sta {z1}

src/main/fragment/cache/fragment-cache-rom6502x.asm

@@ -1,4 +1,4 @@
-//KICKC FRAGMENT CACHE df9b88c62 df9b8b138
+//KICKC FRAGMENT CACHE e65dd24b5 e65dd4993
 //FRAGMENT _deref_pbuc1=_inc__deref_pbuc1
 inc {c1}
 //FRAGMENT isr_hardware_all_entry

src/main/fragment/cache/fragment-cache-wdc65c02.asm

@@ -1,4 +1,4 @@
-//KICKC FRAGMENT CACHE df9b88c62 df9b8b138
+//KICKC FRAGMENT CACHE e65dd24b5 e65dd4993
 //FRAGMENT vbuz1=_deref_pbuc1
 lda {c1}
 sta {z1}

src/main/fragment/mos6502-common/_deref_pbum1=_inc__deref_pbum1.asm

@@ -0,0 +1,9 @@
+ldy {m1}
+sty $fe
+ldy {m1}+1
+sty $ff
+ldy #0
+lda ($fe),y
+clc
+adc #1
+sta ($fe),y

src/test/java/dk/camelot64/kickc/test/TestProgramsFast.java

@@ -9,6 +9,11 @@ import java.io.IOException;
  */
 public class TestProgramsFast extends TestPrograms {
 
+   @Test
+   public void testTmpZpProblem() throws IOException {
+      compileAndCompare("tmp-zp-problem.c", log());
+   }
+
    @Test
    public void testConstBoolReturnProblem() throws IOException {
       compileAndCompare("const-bool-return-problem.c");

src/test/kc/tmp-zp-problem.c

@@ -0,0 +1,30 @@
+// Demonstrates a problem where temporary zp-variables are overwrites each other between different "threads"
+#include <c64.h>
+#include <6502.h>
+
+// Setup the IRQ routine
+void main() {
+    SEI();
+    *KERNEL_IRQ = &irq;
+    CLI();
+
+    for(;;) {
+        for(char i=0;i<10;i++)
+            for(char j=0;j<10;j++) {
+                char k = i+j;
+                if(k>0x80) {
+                    VICII->BORDER_COLOR++;
+                }
+            }
+    }
+}
+
+__mem char * volatile ptr = (char*)0xff00;
+
+
+// The Interrupt Handler
+__interrupt(rom_sys_c64) void irq() {
+    *BG_COLOR = WHITE;
+    (*ptr)++;
+    *BG_COLOR = BLACK;
+}

src/test/ref/tmp-zp-problem.asm

@@ -0,0 +1,92 @@
+// Demonstrates a problem where temporary zp-variables are overwrites each other between different "threads"
+/// @file
+/// Commodore 64 Registers and Constants
+/// @file
+/// The MOS 6526 Complex Interface Adapter (CIA)
+///
+/// http://archive.6502.org/datasheets/mos_6526_cia_recreated.pdf
+  // Commodore 64 PRG executable file
+.file [name="tmp-zp-problem.prg", type="prg", segments="Program"]
+.segmentdef Program [segments="Basic, Code, Data"]
+.segmentdef Basic [start=$0801]
+.segmentdef Code [start=$80d]
+.segmentdef Data [startAfter="Code"]
+.segment Basic
+:BasicUpstart(main)
+  /// The colors of the C64
+  .const BLACK = 0
+  .const WHITE = 1
+  .const OFFSET_STRUCT_MOS6569_VICII_BORDER_COLOR = $20
+  /// $D021 Background Color 0
+  .label BG_COLOR = $d021
+  /// The VIC-II MOS 6567/6569
+  .label VICII = $d000
+  /// The vector used when the KERNAL serves IRQ interrupts
+  .label KERNEL_IRQ = $314
+.segment Code
+// The Interrupt Handler
+irq: {
+    // *BG_COLOR = WHITE
+    lda #WHITE
+    sta BG_COLOR
+    // (*ptr)++;
+    ldy ptr
+    sty.z $fe
+    ldy ptr+1
+    sty.z $ff
+    ldy #0
+    lda ($fe),y
+    clc
+    adc #1
+    sta ($fe),y
+    // *BG_COLOR = BLACK
+    lda #BLACK
+    sta BG_COLOR
+    // }
+    jmp $ea31
+}
+// Setup the IRQ routine
+main: {
+    // asm
+    sei
+    // *KERNEL_IRQ = &irq
+    lda #<irq
+    sta KERNEL_IRQ
+    lda #>irq
+    sta KERNEL_IRQ+1
+    // asm
+    cli
+  __b4:
+    ldx #0
+  __b1:
+    // for(char i=0;i<10;i++)
+    cpx #$a
+    bcc __b6
+    jmp __b4
+  __b6:
+    ldy #0
+  __b2:
+    // for(char j=0;j<10;j++)
+    cpy #$a
+    bcc __b3
+    // for(char i=0;i<10;i++)
+    inx
+    jmp __b1
+  __b3:
+    // char k = i+j
+    txa
+    sty.z $ff
+    clc
+    adc.z $ff
+    // if(k>0x80)
+    cmp #$80+1
+    bcc __b5
+    // VICII->BORDER_COLOR++;
+    inc VICII+OFFSET_STRUCT_MOS6569_VICII_BORDER_COLOR
+  __b5:
+    // for(char j=0;j<10;j++)
+    iny
+    jmp __b2
+}
+.segment Data
+  ptr: .word $ff00

src/test/ref/tmp-zp-problem.cfg

@@ -0,0 +1,45 @@
+
+__interrupt(rom_sys_c64) void irq()
+irq: scope:[irq]  from
+  [0] *BG_COLOR = WHITE
+  [1] *ptr = ++ *ptr
+  [2] *BG_COLOR = BLACK
+  to:irq::@return
+irq::@return: scope:[irq]  from irq
+  [3] return 
+  to:@return
+
+void main()
+main: scope:[main]  from
+  [4] phi()
+  to:main::SEI1
+main::SEI1: scope:[main]  from main
+  asm { sei  }
+  to:main::@7
+main::@7: scope:[main]  from main::SEI1
+  [6] *KERNEL_IRQ = &irq
+  to:main::CLI1
+main::CLI1: scope:[main]  from main::@7
+  asm { cli  }
+  to:main::@1
+main::@1: scope:[main]  from main::@1 main::@4 main::CLI1
+  [8] main::i#2 = phi( main::@1/0, main::@4/main::i#1, main::CLI1/0 )
+  [9] if(main::i#2<$a) goto main::@2
+  to:main::@1
+main::@2: scope:[main]  from main::@1 main::@5
+  [10] main::j#2 = phi( main::@1/0, main::@5/main::j#1 )
+  [11] if(main::j#2<$a) goto main::@3
+  to:main::@4
+main::@4: scope:[main]  from main::@2
+  [12] main::i#1 = ++ main::i#2
+  to:main::@1
+main::@3: scope:[main]  from main::@2
+  [13] main::k#0 = main::i#2 + main::j#2
+  [14] if(main::k#0<$80+1) goto main::@5
+  to:main::@6
+main::@6: scope:[main]  from main::@3
+  [15] *((char *)VICII+OFFSET_STRUCT_MOS6569_VICII_BORDER_COLOR) = ++ *((char *)VICII+OFFSET_STRUCT_MOS6569_VICII_BORDER_COLOR)
+  to:main::@5
+main::@5: scope:[main]  from main::@3 main::@6
+  [16] main::j#1 = ++ main::j#2
+  to:main::@2

src/test/ref/tmp-zp-problem.log

@@ -0,0 +1,628 @@
+Resolved forward reference irq to __interrupt(rom_sys_c64) void irq()
+Inlined call vicSelectGfxBank::$0 = call toDd00(vicSelectGfxBank::gfx)
+Inlined call call SEI
+Inlined call call CLI
+Eliminating unused variable with no statement main::$4
+
+CONTROL FLOW GRAPH SSA
+
+void main()
+main: scope:[main]  from __start
+  to:main::SEI1
+main::SEI1: scope:[main]  from main
+  asm { sei  }
+  to:main::@9
+main::@9: scope:[main]  from main::SEI1
+  *KERNEL_IRQ = &irq
+  to:main::CLI1
+main::CLI1: scope:[main]  from main::@9
+  asm { cli  }
+  to:main::@1
+main::@1: scope:[main]  from main::@2 main::CLI1
+  main::i#0 = 0
+  to:main::@2
+main::@2: scope:[main]  from main::@1 main::@6
+  main::i#2 = phi( main::@1/main::i#0, main::@6/main::i#1 )
+  main::$2 = main::i#2 < $a
+  if(main::$2) goto main::@3
+  to:main::@1
+main::@3: scope:[main]  from main::@2
+  main::i#6 = phi( main::@2/main::i#2 )
+  main::j#0 = 0
+  to:main::@4
+main::@4: scope:[main]  from main::@3 main::@7
+  main::i#5 = phi( main::@3/main::i#6, main::@7/main::i#7 )
+  main::j#2 = phi( main::@3/main::j#0, main::@7/main::j#1 )
+  main::$3 = main::j#2 < $a
+  if(main::$3) goto main::@5
+  to:main::@6
+main::@5: scope:[main]  from main::@4
+  main::j#3 = phi( main::@4/main::j#2 )
+  main::i#3 = phi( main::@4/main::i#5 )
+  main::k#0 = main::i#3 + main::j#3
+  main::$5 = main::k#0 > $80
+  main::$6 = ! main::$5
+  if(main::$6) goto main::@7
+  to:main::@8
+main::@6: scope:[main]  from main::@4
+  main::i#4 = phi( main::@4/main::i#5 )
+  main::i#1 = ++ main::i#4
+  to:main::@2
+main::@7: scope:[main]  from main::@5 main::@8
+  main::i#7 = phi( main::@5/main::i#3, main::@8/main::i#8 )
+  main::j#4 = phi( main::@5/main::j#3, main::@8/main::j#5 )
+  main::j#1 = ++ main::j#4
+  to:main::@4
+main::@8: scope:[main]  from main::@5
+  main::i#8 = phi( main::@5/main::i#3 )
+  main::j#5 = phi( main::@5/main::j#3 )
+  *((char *)VICII+OFFSET_STRUCT_MOS6569_VICII_BORDER_COLOR) = ++ *((char *)VICII+OFFSET_STRUCT_MOS6569_VICII_BORDER_COLOR)
+  to:main::@7
+main::@return: scope:[main]  from
+  return 
+  to:@return
+
+__interrupt(rom_sys_c64) void irq()
+irq: scope:[irq]  from
+  *BG_COLOR = WHITE
+  *ptr = ++ *ptr
+  *BG_COLOR = BLACK
+  to:irq::@return
+irq::@return: scope:[irq]  from irq
+  return 
+  to:@return
+
+void __start()
+__start: scope:[__start]  from
+  call main
+  to:__start::@1
+__start::@1: scope:[__start]  from __start
+  to:__start::@return
+__start::@return: scope:[__start]  from __start::@1
+  return 
+  to:@return
+
+SYMBOL TABLE SSA
+__constant char * const BG_COLOR = (char *)$d021
+__constant const char BLACK = 0
+__constant void (** const KERNEL_IRQ)() = (void (**)())$314
+__constant char OFFSET_STRUCT_MOS6569_VICII_BORDER_COLOR = $20
+__constant struct MOS6569_VICII * const VICII = (struct MOS6569_VICII *)$d000
+__constant const char WHITE = 1
+void __start()
+__interrupt(rom_sys_c64) void irq()
+void main()
+bool main::$2
+bool main::$3
+bool main::$5
+bool main::$6
+char main::i
+char main::i#0
+char main::i#1
+char main::i#2
+char main::i#3
+char main::i#4
+char main::i#5
+char main::i#6
+char main::i#7
+char main::i#8
+char main::j
+char main::j#0
+char main::j#1
+char main::j#2
+char main::j#3
+char main::j#4
+char main::j#5
+char main::k
+char main::k#0
+__loadstore char * volatile ptr = (char *)$ff00
+
+Adding number conversion cast (unumber) $a in main::$2 = main::i#2 < $a
+Adding number conversion cast (unumber) $a in main::$3 = main::j#2 < $a
+Adding number conversion cast (unumber) $80 in main::$5 = main::k#0 > $80
+Successful SSA optimization PassNAddNumberTypeConversions
+Simplifying constant pointer cast (char *) 53281
+Simplifying constant pointer cast (struct MOS6569_VICII *) 53248
+Simplifying constant pointer cast (void (**)()) 788
+Simplifying constant pointer cast (char *) 65280
+Simplifying constant integer cast $a
+Simplifying constant integer cast $a
+Simplifying constant integer cast $80
+Successful SSA optimization PassNCastSimplification
+Finalized unsigned number type (char) $a
+Finalized unsigned number type (char) $a
+Finalized unsigned number type (char) $80
+Successful SSA optimization PassNFinalizeNumberTypeConversions
+Inversing boolean not [15] main::$6 = main::k#0 <= $80 from [14] main::$5 = main::k#0 > $80
+Successful SSA optimization Pass2UnaryNotSimplification
+Alias main::i#2 = main::i#6 
+Alias main::i#3 = main::i#5 main::i#4 main::i#8 
+Alias main::j#2 = main::j#3 main::j#5 
+Successful SSA optimization Pass2AliasElimination
+Alias main::j#2 = main::j#4 
+Alias main::i#3 = main::i#7 
+Successful SSA optimization Pass2AliasElimination
+Identical Phi Values main::i#3 main::i#2
+Successful SSA optimization Pass2IdenticalPhiElimination
+Simple Condition main::$2 [6] if(main::i#2<$a) goto main::@3
+Simple Condition main::$3 [10] if(main::j#2<$a) goto main::@5
+Simple Condition main::$6 [13] if(main::k#0<=$80) goto main::@7
+Successful SSA optimization Pass2ConditionalJumpSimplification
+Constant main::i#0 = 0
+Constant main::j#0 = 0
+Successful SSA optimization Pass2ConstantIdentification
+Rewriting conditional comparison [13] if(main::k#0<=$80) goto main::@7
+Removing unused block main::@return
+Successful SSA optimization Pass2EliminateUnusedBlocks
+Removing unused procedure __start
+Removing unused procedure block __start
+Removing unused procedure block __start::@1
+Removing unused procedure block __start::@return
+Successful SSA optimization PassNEliminateEmptyStart
+Adding number conversion cast (unumber) $80+1 in [8] if(main::k#0<$80+1) goto main::@7
+Adding number conversion cast (unumber) 1 in [8] if(main::k#0<(unumber)$80+1) goto main::@7
+Successful SSA optimization PassNAddNumberTypeConversions
+Simplifying constant integer cast $80+(unumber)1
+Simplifying constant integer cast 1
+Successful SSA optimization PassNCastSimplification
+Finalized unsigned number type (char) 1
+Successful SSA optimization PassNFinalizeNumberTypeConversions
+Inlining constant with var siblings main::i#0
+Inlining constant with var siblings main::j#0
+Constant inlined main::i#0 = 0
+Constant inlined main::j#0 = 0
+Successful SSA optimization Pass2ConstantInlining
+Adding NOP phi() at start of main
+Adding NOP phi() at start of main::@1
+Adding NOP phi() at start of main::@3
+CALL GRAPH
+
+Created 2 initial phi equivalence classes
+Coalesced [15] main::i#9 = main::i#1
+Coalesced [20] main::j#6 = main::j#1
+Coalesced down to 2 phi equivalence classes
+Culled Empty Block label main::@1
+Culled Empty Block label main::@3
+Renumbering block main::@2 to main::@1
+Renumbering block main::@4 to main::@2
+Renumbering block main::@5 to main::@3
+Renumbering block main::@6 to main::@4
+Renumbering block main::@7 to main::@5
+Renumbering block main::@8 to main::@6
+Renumbering block main::@9 to main::@7
+Adding NOP phi() at start of main
+
+FINAL CONTROL FLOW GRAPH
+
+__interrupt(rom_sys_c64) void irq()
+irq: scope:[irq]  from
+  [0] *BG_COLOR = WHITE
+  [1] *ptr = ++ *ptr
+  [2] *BG_COLOR = BLACK
+  to:irq::@return
+irq::@return: scope:[irq]  from irq
+  [3] return 
+  to:@return
+
+void main()
+main: scope:[main]  from
+  [4] phi()
+  to:main::SEI1
+main::SEI1: scope:[main]  from main
+  asm { sei  }
+  to:main::@7
+main::@7: scope:[main]  from main::SEI1
+  [6] *KERNEL_IRQ = &irq
+  to:main::CLI1
+main::CLI1: scope:[main]  from main::@7
+  asm { cli  }
+  to:main::@1
+main::@1: scope:[main]  from main::@1 main::@4 main::CLI1
+  [8] main::i#2 = phi( main::@1/0, main::@4/main::i#1, main::CLI1/0 )
+  [9] if(main::i#2<$a) goto main::@2
+  to:main::@1
+main::@2: scope:[main]  from main::@1 main::@5
+  [10] main::j#2 = phi( main::@1/0, main::@5/main::j#1 )
+  [11] if(main::j#2<$a) goto main::@3
+  to:main::@4
+main::@4: scope:[main]  from main::@2
+  [12] main::i#1 = ++ main::i#2
+  to:main::@1
+main::@3: scope:[main]  from main::@2
+  [13] main::k#0 = main::i#2 + main::j#2
+  [14] if(main::k#0<$80+1) goto main::@5
+  to:main::@6
+main::@6: scope:[main]  from main::@3
+  [15] *((char *)VICII+OFFSET_STRUCT_MOS6569_VICII_BORDER_COLOR) = ++ *((char *)VICII+OFFSET_STRUCT_MOS6569_VICII_BORDER_COLOR)
+  to:main::@5
+main::@5: scope:[main]  from main::@3 main::@6
+  [16] main::j#1 = ++ main::j#2
+  to:main::@2
+
+
+VARIABLE REGISTER WEIGHTS
+__interrupt(rom_sys_c64) void irq()
+void main()
+char main::i
+char main::i#1 // 22.0
+char main::i#2 // 28.0
+char main::j
+char main::j#1 // 202.0
+char main::j#2 // 80.8
+char main::k
+char main::k#0 // 202.0
+__loadstore char * volatile ptr = (char *) 65280 // 4.0
+
+Initial phi equivalence classes
+[ main::i#2 main::i#1 ]
+[ main::j#2 main::j#1 ]
+Added variable main::k#0 to live range equivalence class [ main::k#0 ]
+Added variable ptr to live range equivalence class [ ptr ]
+Complete equivalence classes
+[ main::i#2 main::i#1 ]
+[ main::j#2 main::j#1 ]
+[ main::k#0 ]
+[ ptr ]
+Allocated zp[1]:2 [ main::j#2 main::j#1 ]
+Allocated zp[1]:3 [ main::k#0 ]
+Allocated zp[1]:4 [ main::i#2 main::i#1 ]
+Allocated mem[2] [ ptr ]
+REGISTER UPLIFT POTENTIAL REGISTERS
+Statement [0] *BG_COLOR = WHITE [ ptr ] (  [ ptr ] { }  ) always clobbers reg byte a 
+Statement [1] *ptr = ++ *ptr [ ] (  [ ] { }  ) always clobbers reg byte a reg byte y 
+Statement [2] *BG_COLOR = BLACK [ ] (  [ ] { }  ) always clobbers reg byte a 
+Statement [6] *KERNEL_IRQ = &irq [ ] (  [ ] { }  ) always clobbers reg byte a 
+Statement [13] main::k#0 = main::i#2 + main::j#2 [ main::i#2 main::j#2 main::k#0 ] (  [ main::i#2 main::j#2 main::k#0 ] { }  ) always clobbers reg byte a 
+Removing always clobbered register reg byte a as potential for zp[1]:4 [ main::i#2 main::i#1 ]
+Removing always clobbered register reg byte a as potential for zp[1]:2 [ main::j#2 main::j#1 ]
+Statement [0] *BG_COLOR = WHITE [ ptr ] (  [ ptr ] { }  ) always clobbers reg byte a 
+Statement [1] *ptr = ++ *ptr [ ] (  [ ] { }  ) always clobbers reg byte a reg byte y 
+Statement [2] *BG_COLOR = BLACK [ ] (  [ ] { }  ) always clobbers reg byte a 
+Statement [6] *KERNEL_IRQ = &irq [ ] (  [ ] { }  ) always clobbers reg byte a 
+Statement [13] main::k#0 = main::i#2 + main::j#2 [ main::i#2 main::j#2 main::k#0 ] (  [ main::i#2 main::j#2 main::k#0 ] { }  ) always clobbers reg byte a 
+Potential registers zp[1]:4 [ main::i#2 main::i#1 ] : zp[1]:4 , reg byte x , reg byte y , 
+Potential registers zp[1]:2 [ main::j#2 main::j#1 ] : zp[1]:2 , reg byte x , reg byte y , 
+Potential registers zp[1]:3 [ main::k#0 ] : zp[1]:3 , reg byte a , reg byte x , reg byte y , 
+Potential registers mem[2] [ ptr ] : mem[2] , 
+
+REGISTER UPLIFT SCOPES
+Uplift Scope [main] 282.8: zp[1]:2 [ main::j#2 main::j#1 ] 202: zp[1]:3 [ main::k#0 ] 50: zp[1]:4 [ main::i#2 main::i#1 ] 
+Uplift Scope [] 4: mem[2] [ ptr ] 
+Uplift Scope [MOS6526_CIA] 
+Uplift Scope [MOS6569_VICII] 
+Uplift Scope [MOS6581_SID] 
+Uplift Scope [irq] 
+
+Uplifting [main] best 6098 combination reg byte y [ main::j#2 main::j#1 ] reg byte a [ main::k#0 ] reg byte x [ main::i#2 main::i#1 ] 
+Uplifting [] best 6098 combination mem[2] [ ptr ] 
+Uplifting [MOS6526_CIA] best 6098 combination 
+Uplifting [MOS6569_VICII] best 6098 combination 
+Uplifting [MOS6581_SID] best 6098 combination 
+Uplifting [irq] best 6098 combination 
+
+ASSEMBLER BEFORE OPTIMIZATION
+  // File Comments
+// Demonstrates a problem where temporary zp-variables are overwrites each other between different "threads"
+/// @file
+/// Commodore 64 Registers and Constants
+/// @file
+/// The MOS 6526 Complex Interface Adapter (CIA)
+///
+/// http://archive.6502.org/datasheets/mos_6526_cia_recreated.pdf
+  // Upstart
+  // Commodore 64 PRG executable file
+.file [name="tmp-zp-problem.prg", type="prg", segments="Program"]
+.segmentdef Program [segments="Basic, Code, Data"]
+.segmentdef Basic [start=$0801]
+.segmentdef Code [start=$80d]
+.segmentdef Data [startAfter="Code"]
+.segment Basic
+:BasicUpstart(main)
+  // Global Constants & labels
+  /// The colors of the C64
+  .const BLACK = 0
+  .const WHITE = 1
+  .const OFFSET_STRUCT_MOS6569_VICII_BORDER_COLOR = $20
+  /// $D021 Background Color 0
+  .label BG_COLOR = $d021
+  /// The VIC-II MOS 6567/6569
+  .label VICII = $d000
+  /// The vector used when the KERNAL serves IRQ interrupts
+  .label KERNEL_IRQ = $314
+.segment Code
+  // irq
+// The Interrupt Handler
+irq: {
+    // interrupt(isr_rom_sys_c64_entry) -- isr_rom_sys_c64_entry 
+    // [0] *BG_COLOR = WHITE -- _deref_pbuc1=vbuc2 
+    lda #WHITE
+    sta BG_COLOR
+    // [1] *ptr = ++ *ptr -- _deref_pbum1=_inc__deref_pbum1 
+    ldy ptr
+    sty.z $fe
+    ldy ptr+1
+    sty.z $ff
+    ldy #0
+    lda ($fe),y
+    clc
+    adc #1
+    sta ($fe),y
+    // [2] *BG_COLOR = BLACK -- _deref_pbuc1=vbuc2 
+    lda #BLACK
+    sta BG_COLOR
+    jmp __breturn
+    // irq::@return
+  __breturn:
+    // [3] return 
+    // interrupt(isr_rom_sys_c64_exit) -- isr_rom_sys_c64_exit 
+    jmp $ea31
+}
+  // main
+// Setup the IRQ routine
+main: {
+    jmp SEI1
+    // main::SEI1
+  SEI1:
+    // asm { sei  }
+    sei
+    jmp __b7
+    // main::@7
+  __b7:
+    // [6] *KERNEL_IRQ = &irq -- _deref_qprc1=pprc2 
+    lda #<irq
+    sta KERNEL_IRQ
+    lda #>irq
+    sta KERNEL_IRQ+1
+    jmp CLI1
+    // main::CLI1
+  CLI1:
+    // asm { cli  }
+    cli
+    // [8] phi from main::@1 main::CLI1 to main::@1 [phi:main::@1/main::CLI1->main::@1]
+  __b1_from___b1:
+  __b1_from_CLI1:
+    // [8] phi main::i#2 = 0 [phi:main::@1/main::CLI1->main::@1#0] -- vbuxx=vbuc1 
+    ldx #0
+    jmp __b1
+    // main::@1
+  __b1:
+    // [9] if(main::i#2<$a) goto main::@2 -- vbuxx_lt_vbuc1_then_la1 
+    cpx #$a
+    bcc __b2_from___b1
+    jmp __b1_from___b1
+    // [10] phi from main::@1 to main::@2 [phi:main::@1->main::@2]
+  __b2_from___b1:
+    // [10] phi main::j#2 = 0 [phi:main::@1->main::@2#0] -- vbuyy=vbuc1 
+    ldy #0
+    jmp __b2
+    // main::@2
+  __b2:
+    // [11] if(main::j#2<$a) goto main::@3 -- vbuyy_lt_vbuc1_then_la1 
+    cpy #$a
+    bcc __b3
+    jmp __b4
+    // main::@4
+  __b4:
+    // [12] main::i#1 = ++ main::i#2 -- vbuxx=_inc_vbuxx 
+    inx
+    // [8] phi from main::@4 to main::@1 [phi:main::@4->main::@1]
+  __b1_from___b4:
+    // [8] phi main::i#2 = main::i#1 [phi:main::@4->main::@1#0] -- register_copy 
+    jmp __b1
+    // main::@3
+  __b3:
+    // [13] main::k#0 = main::i#2 + main::j#2 -- vbuaa=vbuxx_plus_vbuyy 
+    txa
+    sty.z $ff
+    clc
+    adc.z $ff
+    // [14] if(main::k#0<$80+1) goto main::@5 -- vbuaa_lt_vbuc1_then_la1 
+    cmp #$80+1
+    bcc __b5
+    jmp __b6
+    // main::@6
+  __b6:
+    // [15] *((char *)VICII+OFFSET_STRUCT_MOS6569_VICII_BORDER_COLOR) = ++ *((char *)VICII+OFFSET_STRUCT_MOS6569_VICII_BORDER_COLOR) -- _deref_pbuc1=_inc__deref_pbuc1 
+    inc VICII+OFFSET_STRUCT_MOS6569_VICII_BORDER_COLOR
+    jmp __b5
+    // main::@5
+  __b5:
+    // [16] main::j#1 = ++ main::j#2 -- vbuyy=_inc_vbuyy 
+    iny
+    // [10] phi from main::@5 to main::@2 [phi:main::@5->main::@2]
+  __b2_from___b5:
+    // [10] phi main::j#2 = main::j#1 [phi:main::@5->main::@2#0] -- register_copy 
+    jmp __b2
+}
+  // File Data
+.segment Data
+  ptr: .word $ff00
+
+ASSEMBLER OPTIMIZATIONS
+Removing instruction jmp __breturn
+Removing instruction jmp SEI1
+Removing instruction jmp __b7
+Removing instruction jmp CLI1
+Removing instruction jmp __b1
+Removing instruction jmp __b2
+Removing instruction jmp __b4
+Removing instruction jmp __b6
+Removing instruction jmp __b5
+Succesful ASM optimization Pass5NextJumpElimination
+Replacing label __b1_from___b1 with __b1_from_CLI1
+Removing instruction __b1_from___b1:
+Succesful ASM optimization Pass5RedundantLabelElimination
+Removing instruction __breturn:
+Removing instruction SEI1:
+Removing instruction __b7:
+Removing instruction CLI1:
+Removing instruction __b4:
+Removing instruction __b1_from___b4:
+Removing instruction __b6:
+Removing instruction __b2_from___b5:
+Succesful ASM optimization Pass5UnusedLabelElimination
+Relabelling long label __b1_from_CLI1 to __b4
+Relabelling long label __b2_from___b1 to __b6
+Succesful ASM optimization Pass5RelabelLongLabels
+
+FINAL SYMBOL TABLE
+__constant char * const BG_COLOR = (char *) 53281
+__constant const char BLACK = 0
+__constant void (** const KERNEL_IRQ)() = (void (**)()) 788
+__constant char OFFSET_STRUCT_MOS6569_VICII_BORDER_COLOR = $20
+__constant struct MOS6569_VICII * const VICII = (struct MOS6569_VICII *) 53248
+__constant const char WHITE = 1
+__interrupt(rom_sys_c64) void irq()
+void main()
+char main::i
+char main::i#1 // reg byte x 22.0
+char main::i#2 // reg byte x 28.0
+char main::j
+char main::j#1 // reg byte y 202.0
+char main::j#2 // reg byte y 80.8
+char main::k
+char main::k#0 // reg byte a 202.0
+__loadstore char * volatile ptr = (char *) 65280 // mem[2] 4.0
+
+reg byte x [ main::i#2 main::i#1 ]
+reg byte y [ main::j#2 main::j#1 ]
+reg byte a [ main::k#0 ]
+mem[2] [ ptr ]
+
+
+FINAL ASSEMBLER
+Score: 4559
+
+  // File Comments
+// Demonstrates a problem where temporary zp-variables are overwrites each other between different "threads"
+/// @file
+/// Commodore 64 Registers and Constants
+/// @file
+/// The MOS 6526 Complex Interface Adapter (CIA)
+///
+/// http://archive.6502.org/datasheets/mos_6526_cia_recreated.pdf
+  // Upstart
+  // Commodore 64 PRG executable file
+.file [name="tmp-zp-problem.prg", type="prg", segments="Program"]
+.segmentdef Program [segments="Basic, Code, Data"]
+.segmentdef Basic [start=$0801]
+.segmentdef Code [start=$80d]
+.segmentdef Data [startAfter="Code"]
+.segment Basic
+:BasicUpstart(main)
+  // Global Constants & labels
+  /// The colors of the C64
+  .const BLACK = 0
+  .const WHITE = 1
+  .const OFFSET_STRUCT_MOS6569_VICII_BORDER_COLOR = $20
+  /// $D021 Background Color 0
+  .label BG_COLOR = $d021
+  /// The VIC-II MOS 6567/6569
+  .label VICII = $d000
+  /// The vector used when the KERNAL serves IRQ interrupts
+  .label KERNEL_IRQ = $314
+.segment Code
+  // irq
+// The Interrupt Handler
+irq: {
+    // interrupt(isr_rom_sys_c64_entry) -- isr_rom_sys_c64_entry 
+    // *BG_COLOR = WHITE
+    // [0] *BG_COLOR = WHITE -- _deref_pbuc1=vbuc2 
+    lda #WHITE
+    sta BG_COLOR
+    // (*ptr)++;
+    // [1] *ptr = ++ *ptr -- _deref_pbum1=_inc__deref_pbum1 
+    ldy ptr
+    sty.z $fe
+    ldy ptr+1
+    sty.z $ff
+    ldy #0
+    lda ($fe),y
+    clc
+    adc #1
+    sta ($fe),y
+    // *BG_COLOR = BLACK
+    // [2] *BG_COLOR = BLACK -- _deref_pbuc1=vbuc2 
+    lda #BLACK
+    sta BG_COLOR
+    // irq::@return
+    // }
+    // [3] return 
+    // interrupt(isr_rom_sys_c64_exit) -- isr_rom_sys_c64_exit 
+    jmp $ea31
+}
+  // main
+// Setup the IRQ routine
+main: {
+    // main::SEI1
+    // asm
+    // asm { sei  }
+    sei
+    // main::@7
+    // *KERNEL_IRQ = &irq
+    // [6] *KERNEL_IRQ = &irq -- _deref_qprc1=pprc2 
+    lda #<irq
+    sta KERNEL_IRQ
+    lda #>irq
+    sta KERNEL_IRQ+1
+    // main::CLI1
+    // asm
+    // asm { cli  }
+    cli
+    // [8] phi from main::@1 main::CLI1 to main::@1 [phi:main::@1/main::CLI1->main::@1]
+  __b4:
+    // [8] phi main::i#2 = 0 [phi:main::@1/main::CLI1->main::@1#0] -- vbuxx=vbuc1 
+    ldx #0
+    // main::@1
+  __b1:
+    // for(char i=0;i<10;i++)
+    // [9] if(main::i#2<$a) goto main::@2 -- vbuxx_lt_vbuc1_then_la1 
+    cpx #$a
+    bcc __b6
+    jmp __b4
+    // [10] phi from main::@1 to main::@2 [phi:main::@1->main::@2]
+  __b6:
+    // [10] phi main::j#2 = 0 [phi:main::@1->main::@2#0] -- vbuyy=vbuc1 
+    ldy #0
+    // main::@2
+  __b2:
+    // for(char j=0;j<10;j++)
+    // [11] if(main::j#2<$a) goto main::@3 -- vbuyy_lt_vbuc1_then_la1 
+    cpy #$a
+    bcc __b3
+    // main::@4
+    // for(char i=0;i<10;i++)
+    // [12] main::i#1 = ++ main::i#2 -- vbuxx=_inc_vbuxx 
+    inx
+    // [8] phi from main::@4 to main::@1 [phi:main::@4->main::@1]
+    // [8] phi main::i#2 = main::i#1 [phi:main::@4->main::@1#0] -- register_copy 
+    jmp __b1
+    // main::@3
+  __b3:
+    // char k = i+j
+    // [13] main::k#0 = main::i#2 + main::j#2 -- vbuaa=vbuxx_plus_vbuyy 
+    txa
+    sty.z $ff
+    clc
+    adc.z $ff
+    // if(k>0x80)
+    // [14] if(main::k#0<$80+1) goto main::@5 -- vbuaa_lt_vbuc1_then_la1 
+    cmp #$80+1
+    bcc __b5
+    // main::@6
+    // VICII->BORDER_COLOR++;
+    // [15] *((char *)VICII+OFFSET_STRUCT_MOS6569_VICII_BORDER_COLOR) = ++ *((char *)VICII+OFFSET_STRUCT_MOS6569_VICII_BORDER_COLOR) -- _deref_pbuc1=_inc__deref_pbuc1 
+    inc VICII+OFFSET_STRUCT_MOS6569_VICII_BORDER_COLOR
+    // main::@5
+  __b5:
+    // for(char j=0;j<10;j++)
+    // [16] main::j#1 = ++ main::j#2 -- vbuyy=_inc_vbuyy 
+    iny
+    // [10] phi from main::@5 to main::@2 [phi:main::@5->main::@2]
+    // [10] phi main::j#2 = main::j#1 [phi:main::@5->main::@2#0] -- register_copy 
+    jmp __b2
+}
+  // File Data
+.segment Data
+  ptr: .word $ff00
+

src/test/ref/tmp-zp-problem.sym

@@ -0,0 +1,22 @@
+__constant char * const BG_COLOR = (char *) 53281
+__constant const char BLACK = 0
+__constant void (** const KERNEL_IRQ)() = (void (**)()) 788
+__constant char OFFSET_STRUCT_MOS6569_VICII_BORDER_COLOR = $20
+__constant struct MOS6569_VICII * const VICII = (struct MOS6569_VICII *) 53248
+__constant const char WHITE = 1
+__interrupt(rom_sys_c64) void irq()
+void main()
+char main::i
+char main::i#1 // reg byte x 22.0
+char main::i#2 // reg byte x 28.0
+char main::j
+char main::j#1 // reg byte y 202.0
+char main::j#2 // reg byte y 80.8
+char main::k
+char main::k#0 // reg byte a 202.0
+__loadstore char * volatile ptr = (char *) 65280 // mem[2] 4.0
+
+reg byte x [ main::i#2 main::i#1 ]
+reg byte y [ main::j#2 main::j#1 ]
+reg byte a [ main::k#0 ]
+mem[2] [ ptr ]