
CONTROL FLOW GRAPH SSA

void main()
main: scope:[main]  from __start
  main::i#0 = 0
  to:main::@1
main::@1: scope:[main]  from main main::@2
  main::i#2 = phi( main/main::i#0, main::@2/main::i#1 )
  main::$0 = main::i#2 < $a
  if(main::$0) goto main::@2
  to:main::@return
main::@2: scope:[main]  from main::@1
  main::i#3 = phi( main::@1/main::i#2 )
  main::$2 = (char)main::i#3
  main::$1 = main::$2 * SIZEOF_INT
  main::SCREEN[main::$1] = main::i#3
  main::i#1 = ++ main::i#3
  to:main::@1
main::@return: scope:[main]  from main::@1
  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 SIZEOF_INT = 2
void __start()
void main()
bool main::$0
char main::$1
char main::$2
__constant int * const main::SCREEN = (int *)$400
int main::i
int main::i#0
int main::i#1
int main::i#2
int main::i#3

Adding number conversion cast (snumber) $a in main::$0 = main::i#2 < $a
Successful SSA optimization PassNAddNumberTypeConversions
Simplifying constant pointer cast (int *) 1024
Simplifying constant integer cast $a
Successful SSA optimization PassNCastSimplification
Finalized signed number type (signed char) $a
Successful SSA optimization PassNFinalizeNumberTypeConversions
Alias main::i#2 = main::i#3 
Successful SSA optimization Pass2AliasElimination
Simple Condition main::$0 [3] if(main::i#2<$a) goto main::@2
Successful SSA optimization Pass2ConditionalJumpSimplification
Constant main::i#0 = 0
Successful SSA optimization Pass2ConstantIdentification
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
Rewriting multiplication to use shift [3] main::$1 = main::$2 * SIZEOF_INT
Successful SSA optimization Pass2MultiplyToShiftRewriting
Inlining constant with var siblings main::i#0
Constant inlined main::i#0 = 0
Successful SSA optimization Pass2ConstantInlining
Eliminating unused constant SIZEOF_INT
Successful SSA optimization PassNEliminateUnusedVars
Adding NOP phi() at start of main
CALL GRAPH

Created 1 initial phi equivalence classes
Coalesced [8] main::i#4 = main::i#1
Coalesced down to 1 phi equivalence classes
Adding NOP phi() at start of main

FINAL CONTROL FLOW GRAPH

void main()
main: scope:[main]  from
  [0] phi()
  to:main::@1
main::@1: scope:[main]  from main main::@2
  [1] main::i#2 = phi( main/0, main::@2/main::i#1 )
  [2] if(main::i#2<$a) goto main::@2
  to:main::@return
main::@return: scope:[main]  from main::@1
  [3] return 
  to:@return
main::@2: scope:[main]  from main::@1
  [4] main::$2 = (char)main::i#2
  [5] main::$1 = main::$2 << 1
  [6] main::SCREEN[main::$1] = main::i#2
  [7] main::i#1 = ++ main::i#2
  to:main::@1


VARIABLE REGISTER WEIGHTS
void main()
char main::$1 // 22.0
char main::$2 // 22.0
int main::i
int main::i#1 // 22.0
int main::i#2 // 8.8

Initial phi equivalence classes
[ main::i#2 main::i#1 ]
Added variable main::$2 to live range equivalence class [ main::$2 ]
Added variable main::$1 to live range equivalence class [ main::$1 ]
Complete equivalence classes
[ main::i#2 main::i#1 ]
[ main::$2 ]
[ main::$1 ]
Zero-page exhausted. Moving allocation to main memory main::i#2
Allocated mem[2] [ main::i#2 main::i#1 ]
Zero-page exhausted. Moving allocation to main memory main::$2
Allocated mem[1] [ main::$2 ]
Zero-page exhausted. Moving allocation to main memory main::$1
Allocated mem[1] [ main::$1 ]
REGISTER UPLIFT POTENTIAL REGISTERS
Statement [2] if(main::i#2<$a) goto main::@2 [ main::i#2 ] (  [ main::i#2 ] { }  ) always clobbers reg byte a 
Statement [4] main::$2 = (char)main::i#2 [ main::i#2 main::$2 ] (  [ main::i#2 main::$2 ] { }  ) always clobbers reg byte a 
Statement [5] main::$1 = main::$2 << 1 [ main::i#2 main::$1 ] (  [ main::i#2 main::$1 ] { }  ) always clobbers reg byte a 
Statement [6] main::SCREEN[main::$1] = main::i#2 [ main::i#2 ] (  [ main::i#2 ] { }  ) always clobbers reg byte a 
Potential registers mem[2] [ main::i#2 main::i#1 ] : mem[2] , 
Potential registers mem[1] [ main::$2 ] : mem[1] , reg byte a , reg byte x , reg byte y , 
Potential registers mem[1] [ main::$1 ] : mem[1] , reg byte a , reg byte x , reg byte y , 

REGISTER UPLIFT SCOPES
Uplift Scope [main] 30.8: mem[2] [ main::i#2 main::i#1 ] 22: mem[1] [ main::$2 ] 22: mem[1] [ main::$1 ] 
Uplift Scope [] 

Uplifting [main] best 841 combination mem[2] [ main::i#2 main::i#1 ] reg byte a [ main::$2 ] reg byte a [ main::$1 ] 
Uplifting [] best 841 combination 
Zero-page exhausted. Moving allocation to main memory main::i#2

ASSEMBLER BEFORE OPTIMIZATION
  // File Comments
// Tests warning when running out of zeropage-addresses for variables
  // Upstart
  // Commodore 64 PRG executable file
.file [name="zeropage-exhausted.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
.segment Code
  // main
// And then allocate a 2-byte-variable
main: {
    .label SCREEN = $400
    // [1] phi from main to main::@1 [phi:main->main::@1]
  __b1_from_main:
    // [1] phi main::i#2 = 0 [phi:main->main::@1#0] -- vwsm1=vwsc1 
    lda #<0
    sta i
    lda #>0
    sta i+1
    jmp __b1
    // main::@1
  __b1:
    // [2] if(main::i#2<$a) goto main::@2 -- vwsm1_lt_vwuc1_then_la1 
    lda i+1
    bmi __b2
    cmp #>$a
    bcc __b2
    bne !+
    lda i
    cmp #<$a
    bcc __b2
  !:
    jmp __breturn
    // main::@return
  __breturn:
    // [3] return 
    rts
    // main::@2
  __b2:
    // [4] main::$2 = (char)main::i#2 -- vbuaa=_byte_vwsm1 
    lda i
    // [5] main::$1 = main::$2 << 1 -- vbuaa=vbuaa_rol_1 
    asl
    // [6] main::SCREEN[main::$1] = main::i#2 -- pwsc1_derefidx_vbuaa=vwsm1 
    tay
    lda i
    sta SCREEN,y
    lda i+1
    sta SCREEN+1,y
    // [7] main::i#1 = ++ main::i#2 -- vwsm1=_inc_vwsm1 
    inc i
    bne !+
    inc i+1
  !:
    // [1] phi from main::@2 to main::@1 [phi:main::@2->main::@1]
  __b1_from___b2:
    // [1] phi main::i#2 = main::i#1 [phi:main::@2->main::@1#0] -- register_copy 
    jmp __b1
  .segment Data
    i: .word 0
}
  // File Data

ASSEMBLER OPTIMIZATIONS
Removing instruction jmp __b1
Removing instruction jmp __breturn
Succesful ASM optimization Pass5NextJumpElimination
Removing instruction lda #>0
Succesful ASM optimization Pass5UnnecesaryLoadElimination
Removing instruction __b1_from_main:
Removing instruction __breturn:
Removing instruction __b1_from___b2:
Succesful ASM optimization Pass5UnusedLabelElimination

FINAL SYMBOL TABLE
void main()
char main::$1 // reg byte a 22.0
char main::$2 // reg byte a 22.0
__constant int * const main::SCREEN = (int *) 1024
int main::i
int main::i#1 // i mem[2] 22.0
int main::i#2 // i mem[2] 8.8

mem[2] [ main::i#2 main::i#1 ]
reg byte a [ main::$2 ]
reg byte a [ main::$1 ]


FINAL ASSEMBLER
Score: 761

  // File Comments
// Tests warning when running out of zeropage-addresses for variables
  // Upstart
  // Commodore 64 PRG executable file
.file [name="zeropage-exhausted.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
.segment Code
  // main
// And then allocate a 2-byte-variable
main: {
    .label SCREEN = $400
    // [1] phi from main to main::@1 [phi:main->main::@1]
    // [1] phi main::i#2 = 0 [phi:main->main::@1#0] -- vwsm1=vwsc1 
    lda #<0
    sta i
    sta i+1
    // main::@1
  __b1:
    // for(__zp int i=0;i<10;i++)
    // [2] if(main::i#2<$a) goto main::@2 -- vwsm1_lt_vwuc1_then_la1 
    lda i+1
    bmi __b2
    cmp #>$a
    bcc __b2
    bne !+
    lda i
    cmp #<$a
    bcc __b2
  !:
    // main::@return
    // }
    // [3] return 
    rts
    // main::@2
  __b2:
    // SCREEN[(char)i] = i
    // [4] main::$2 = (char)main::i#2 -- vbuaa=_byte_vwsm1 
    lda i
    // [5] main::$1 = main::$2 << 1 -- vbuaa=vbuaa_rol_1 
    asl
    // [6] main::SCREEN[main::$1] = main::i#2 -- pwsc1_derefidx_vbuaa=vwsm1 
    tay
    lda i
    sta SCREEN,y
    lda i+1
    sta SCREEN+1,y
    // for(__zp int i=0;i<10;i++)
    // [7] main::i#1 = ++ main::i#2 -- vwsm1=_inc_vwsm1 
    inc i
    bne !+
    inc i+1
  !:
    // [1] phi from main::@2 to main::@1 [phi:main::@2->main::@1]
    // [1] phi main::i#2 = main::i#1 [phi:main::@2->main::@1#0] -- register_copy 
    jmp __b1
  .segment Data
    i: .word 0
}
  // File Data

