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::@1
  main::i#2 = phi( main/main::i#0, main::@1/main::i#1 )
  plots[main::i#2] = main::i#2
  SCREEN[main::i#2] = 0
  main::i#1 = main::i#2 + rangenext(0,$27)
  main::$0 = main::i#1 != rangelast(0,$27)
  if(main::$0) goto main::@1
  to:main::@2
main::@2: scope:[main]  from main::@1 main::@3
  line::x0#0 = 0
  line::x1#0 = $a
  call line
  to:main::@3
main::@3: scope:[main]  from main::@2
  if(true) goto main::@2
  to:main::@return
main::@return: scope:[main]  from main::@3
  return 
  to:@return

void line(char x0 , char x1)
line: scope:[line]  from main::@2
  line::x1#1 = phi( main::@2/line::x1#0 )
  line::x0#1 = phi( main::@2/line::x0#0 )
  line::$0 = line::x0#1 < line::x1#1
  if(line::$0) goto line::@1
  to:line::@2
line::@1: scope:[line]  from line
  line::x1#3 = phi( line/line::x1#1 )
  line::x0#2 = phi( line/line::x0#1 )
  line::x#0 = line::x0#2
  to:line::@3
line::@2: scope:[line]  from line
  line::x0#3 = phi( line/line::x0#1 )
  plot::x#0 = line::x0#3
  call plot
  to:line::@5
line::@5: scope:[line]  from line::@2
  to:line::@return
line::@3: scope:[line]  from line::@1 line::@6
  line::x1#2 = phi( line::@1/line::x1#3, line::@6/line::x1#4 )
  line::x#2 = phi( line::@1/line::x#0, line::@6/line::x#1 )
  line::$2 = line::x#2 <= line::x1#2
  if(line::$2) goto line::@4
  to:line::@return
line::@4: scope:[line]  from line::@3
  line::x1#5 = phi( line::@3/line::x1#2 )
  line::x#3 = phi( line::@3/line::x#2 )
  plot::x#1 = line::x#3
  call plot
  to:line::@6
line::@6: scope:[line]  from line::@4
  line::x1#4 = phi( line::@4/line::x1#5 )
  line::x#4 = phi( line::@4/line::x#3 )
  line::x#1 = ++ line::x#4
  to:line::@3
line::@return: scope:[line]  from line::@3 line::@5
  return 
  to:@return

void plot(char x)
plot: scope:[plot]  from line::@2 line::@4
  plot::x#2 = phi( line::@2/plot::x#0, line::@4/plot::x#1 )
  plot::idx#0 = plots[plot::x#2]
  plot::$0 = SCREEN[plot::idx#0] + 1
  SCREEN[plot::idx#0] = plot::$0
  to:plot::@return
plot::@return: scope:[plot]  from plot
  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 SCREEN = (char *)$400
void __start()
void line(char x0 , char x1)
bool line::$0
bool line::$2
char line::x
char line::x#0
char line::x#1
char line::x#2
char line::x#3
char line::x#4
char line::x0
char line::x0#0
char line::x0#1
char line::x0#2
char line::x0#3
char line::x1
char line::x1#0
char line::x1#1
char line::x1#2
char line::x1#3
char line::x1#4
char line::x1#5
void main()
bool main::$0
char main::i
char main::i#0
char main::i#1
char main::i#2
void plot(char x)
number plot::$0
char plot::idx
char plot::idx#0
char plot::x
char plot::x#0
char plot::x#1
char plot::x#2
__constant char * const plots = (char *)$1000

Adding number conversion cast (unumber) 0 in SCREEN[main::i#2] = 0
Adding number conversion cast (unumber) 0 in line::x0#0 = 0
Adding number conversion cast (unumber) $a in line::x1#0 = $a
Adding number conversion cast (unumber) 1 in plot::$0 = SCREEN[plot::idx#0] + 1
Adding number conversion cast (unumber) plot::$0 in plot::$0 = SCREEN[plot::idx#0] + (unumber)1
Successful SSA optimization PassNAddNumberTypeConversions
Inlining cast SCREEN[main::i#2] = (unumber)0
Inlining cast line::x0#0 = (unumber)0
Inlining cast line::x1#0 = (unumber)$a
Successful SSA optimization Pass2InlineCast
Simplifying constant pointer cast (char *) 4096
Simplifying constant pointer cast (char *) 1024
Simplifying constant integer cast 0
Simplifying constant integer cast 0
Simplifying constant integer cast $a
Simplifying constant integer cast 1
Successful SSA optimization PassNCastSimplification
Finalized unsigned number type (char) 0
Finalized unsigned number type (char) 0
Finalized unsigned number type (char) $a
Finalized unsigned number type (char) 1
Successful SSA optimization PassNFinalizeNumberTypeConversions
Inferred type updated to char in plot::$0 = SCREEN[plot::idx#0] + 1
Alias line::x0#1 = line::x0#2 line::x#0 line::x0#3 
Alias line::x1#1 = line::x1#3 
Alias line::x#2 = line::x#3 line::x#4 
Alias line::x1#2 = line::x1#5 line::x1#4 
Successful SSA optimization Pass2AliasElimination
Identical Phi Values line::x0#1 line::x0#0
Identical Phi Values line::x1#1 line::x1#0
Identical Phi Values line::x1#2 line::x1#1
Successful SSA optimization Pass2IdenticalPhiElimination
Simple Condition main::$0 [6] if(main::i#1!=rangelast(0,$27)) goto main::@1
Simple Condition line::$0 [14] if(line::x0#0<line::x1#0) goto line::@1
Simple Condition line::$2 [19] if(line::x#2<=line::x1#0) goto line::@4
Successful SSA optimization Pass2ConditionalJumpSimplification
Constant main::i#0 = 0
Constant line::x0#0 = 0
Constant line::x1#0 = $a
Successful SSA optimization Pass2ConstantIdentification
Constant plot::x#0 = line::x0#0
Successful SSA optimization Pass2ConstantIdentification
if() condition always true - replacing block destination [10] if(true) goto main::@2
if() condition always true - replacing block destination [14] if(line::x0#0<line::x1#0) goto line::@1
Successful SSA optimization Pass2ConstantIfs
Resolved ranged next value [4] main::i#1 = ++ main::i#2 to ++
Resolved ranged comparison value [6] if(main::i#1!=rangelast(0,$27)) goto main::@1 to $28
Rewriting conditional comparison [19] if(line::x#2<=line::x1#0) goto line::@4
Removing unused block main::@return
Removing PHI-reference to removed block (line::@2) in block plot
Removing unused block line::@2
Removing unused block line::@5
Successful SSA optimization Pass2EliminateUnusedBlocks
Eliminating unused constant plot::x#0
Successful SSA optimization PassNEliminateUnusedVars
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) $28 in [4] if(main::i#1!=$28) goto main::@1
Adding number conversion cast (unumber) line::x1#0+1 in [7] if(line::x#2<line::x1#0+1) goto line::@4
Adding number conversion cast (unumber) 1 in [7] if(line::x#2<(unumber)line::x1#0+1) goto line::@4
Successful SSA optimization PassNAddNumberTypeConversions
Simplifying constant integer cast $28
Simplifying constant integer cast line::x1#0+(unumber)1
Simplifying constant integer cast 1
Successful SSA optimization PassNCastSimplification
Finalized unsigned number type (char) $28
Finalized unsigned number type (char) 1
Successful SSA optimization PassNFinalizeNumberTypeConversions
Identical Phi Values plot::x#2 plot::x#1
Successful SSA optimization Pass2IdenticalPhiElimination
Inlining constant with var siblings main::i#0
Constant inlined main::i#0 = 0
Successful SSA optimization Pass2ConstantInlining
Added new block during phi lifting main::@4(between main::@1 and main::@1)
Adding NOP phi() at start of main
Adding NOP phi() at start of main::@2
Adding NOP phi() at start of main::@3
Adding NOP phi() at start of line
Adding NOP phi() at start of line::@1
CALL GRAPH
Calls in [main] to line:7 
Calls in [line] to plot:16 

Created 2 initial phi equivalence classes
Coalesced [9] main::i#3 = main::i#1
Coalesced [18] line::x#5 = line::x#1
Coalesced down to 2 phi equivalence classes
Culled Empty Block label main::@3
Culled Empty Block label main::@4
Culled Empty Block label line::@1
Renumbering block line::@3 to line::@1
Renumbering block line::@4 to line::@2
Renumbering block line::@6 to line::@3
Adding NOP phi() at start of main
Adding NOP phi() at start of main::@2
Adding NOP phi() at start of line

FINAL CONTROL FLOW GRAPH

void main()
main: scope:[main]  from
  [0] phi()
  to:main::@1
main::@1: scope:[main]  from main main::@1
  [1] main::i#2 = phi( main/0, main::@1/main::i#1 )
  [2] plots[main::i#2] = main::i#2
  [3] SCREEN[main::i#2] = 0
  [4] main::i#1 = ++ main::i#2
  [5] if(main::i#1!=$28) goto main::@1
  to:main::@2
main::@2: scope:[main]  from main::@1 main::@2
  [6] phi()
  [7] call line
  to:main::@2

void line(char x0 , char x1)
line: scope:[line]  from main::@2
  [8] phi()
  to:line::@1
line::@1: scope:[line]  from line line::@3
  [9] line::x#2 = phi( line/line::x0#0, line::@3/line::x#1 )
  [10] if(line::x#2<line::x1#0+1) goto line::@2
  to:line::@return
line::@return: scope:[line]  from line::@1
  [11] return 
  to:@return
line::@2: scope:[line]  from line::@1
  [12] plot::x#1 = line::x#2
  [13] call plot
  to:line::@3
line::@3: scope:[line]  from line::@2
  [14] line::x#1 = ++ line::x#2
  to:line::@1

void plot(char x)
plot: scope:[plot]  from line::@2
  [15] plot::idx#0 = plots[plot::x#1]
  [16] plot::$0 = SCREEN[plot::idx#0] + 1
  [17] SCREEN[plot::idx#0] = plot::$0
  to:plot::@return
plot::@return: scope:[plot]  from plot
  [18] return 
  to:@return


VARIABLE REGISTER WEIGHTS
void line(char x0 , char x1)
char line::x
char line::x#1 // 20002.0
char line::x#2 // 10001.0
char line::x0
char line::x1
void main()
char main::i
char main::i#1 // 16.5
char main::i#2 // 18.333333333333332
void plot(char x)
char plot::$0 // 200002.0
char plot::idx
char plot::idx#0 // 150001.5
char plot::x
char plot::x#1 // 110002.0

Initial phi equivalence classes
[ main::i#2 main::i#1 ]
[ line::x#2 line::x#1 ]
Added variable plot::x#1 to live range equivalence class [ plot::x#1 ]
Added variable plot::idx#0 to live range equivalence class [ plot::idx#0 ]
Added variable plot::$0 to live range equivalence class [ plot::$0 ]
Complete equivalence classes
[ main::i#2 main::i#1 ]
[ line::x#2 line::x#1 ]
[ plot::x#1 ]
[ plot::idx#0 ]
[ plot::$0 ]
Allocated zp[1]:2 [ main::i#2 main::i#1 ]
Allocated zp[1]:3 [ line::x#2 line::x#1 ]
Allocated zp[1]:4 [ plot::x#1 ]
Allocated zp[1]:5 [ plot::idx#0 ]
Allocated zp[1]:6 [ plot::$0 ]
REGISTER UPLIFT POTENTIAL REGISTERS
Statement [3] SCREEN[main::i#2] = 0 [ main::i#2 ] (  [ main::i#2 ] { }  ) always clobbers reg byte a 
Removing always clobbered register reg byte a as potential for zp[1]:2 [ main::i#2 main::i#1 ]
Statement [2] plots[main::i#2] = main::i#2 [ main::i#2 ] (  [ main::i#2 ] { }  ) always clobbers reg byte a 
Statement [3] SCREEN[main::i#2] = 0 [ main::i#2 ] (  [ main::i#2 ] { }  ) always clobbers reg byte a 
Potential registers zp[1]:2 [ main::i#2 main::i#1 ] : zp[1]:2 , reg byte x , reg byte y , 
Potential registers zp[1]:3 [ line::x#2 line::x#1 ] : zp[1]:3 , reg byte a , reg byte x , reg byte y , 
Potential registers zp[1]:4 [ plot::x#1 ] : zp[1]:4 , reg byte a , reg byte x , reg byte y , 
Potential registers zp[1]:5 [ plot::idx#0 ] : zp[1]:5 , reg byte a , reg byte x , reg byte y , 
Potential registers zp[1]:6 [ plot::$0 ] : zp[1]:6 , reg byte a , reg byte x , reg byte y , 

REGISTER UPLIFT SCOPES
Uplift Scope [plot] 200,002: zp[1]:6 [ plot::$0 ] 150,001.5: zp[1]:5 [ plot::idx#0 ] 110,002: zp[1]:4 [ plot::x#1 ] 
Uplift Scope [line] 30,003: zp[1]:3 [ line::x#2 line::x#1 ] 
Uplift Scope [main] 34.83: zp[1]:2 [ main::i#2 main::i#1 ] 
Uplift Scope [] 

Uplifting [plot] best 4356 combination reg byte a [ plot::$0 ] reg byte y [ plot::idx#0 ] reg byte x [ plot::x#1 ] 
Uplifting [line] best 3156 combination reg byte x [ line::x#2 line::x#1 ] 
Uplifting [main] best 3006 combination reg byte x [ main::i#2 main::i#1 ] 
Uplifting [] best 3006 combination 

ASSEMBLER BEFORE OPTIMIZATION
  // File Comments
  // Upstart
  // Commodore 64 PRG executable file
.file [name="const-identification.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
  .label plots = $1000
  .label SCREEN = $400
.segment Code
  // main
main: {
    // [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] -- vbuxx=vbuc1 
    ldx #0
    jmp __b1
    // [1] phi from main::@1 to main::@1 [phi:main::@1->main::@1]
  __b1_from___b1:
    // [1] phi main::i#2 = main::i#1 [phi:main::@1->main::@1#0] -- register_copy 
    jmp __b1
    // main::@1
  __b1:
    // [2] plots[main::i#2] = main::i#2 -- pbuc1_derefidx_vbuxx=vbuxx 
    txa
    sta plots,x
    // [3] SCREEN[main::i#2] = 0 -- pbuc1_derefidx_vbuxx=vbuc2 
    lda #0
    sta SCREEN,x
    // [4] main::i#1 = ++ main::i#2 -- vbuxx=_inc_vbuxx 
    inx
    // [5] if(main::i#1!=$28) goto main::@1 -- vbuxx_neq_vbuc1_then_la1 
    cpx #$28
    bne __b1_from___b1
    // [6] phi from main::@1 main::@2 to main::@2 [phi:main::@1/main::@2->main::@2]
  __b2_from___b1:
  __b2_from___b2:
    jmp __b2
    // main::@2
  __b2:
    // [7] call line
    // [8] phi from main::@2 to line [phi:main::@2->line]
  line_from___b2:
    jsr line
    jmp __b2_from___b2
}
  // line
// void line(char x0, char x1)
line: {
    .const x0 = 0
    .const x1 = $a
    // [9] phi from line to line::@1 [phi:line->line::@1]
  __b1_from_line:
    // [9] phi line::x#2 = line::x0#0 [phi:line->line::@1#0] -- vbuxx=vbuc1 
    ldx #x0
    jmp __b1
    // line::@1
  __b1:
    // [10] if(line::x#2<line::x1#0+1) goto line::@2 -- vbuxx_lt_vbuc1_then_la1 
    cpx #x1+1
    bcc __b2
    jmp __breturn
    // line::@return
  __breturn:
    // [11] return 
    rts
    // line::@2
  __b2:
    // [12] plot::x#1 = line::x#2
    // [13] call plot
    jsr plot
    jmp __b3
    // line::@3
  __b3:
    // [14] line::x#1 = ++ line::x#2 -- vbuxx=_inc_vbuxx 
    inx
    // [9] phi from line::@3 to line::@1 [phi:line::@3->line::@1]
  __b1_from___b3:
    // [9] phi line::x#2 = line::x#1 [phi:line::@3->line::@1#0] -- register_copy 
    jmp __b1
}
  // plot
// void plot(__register(X) char x)
plot: {
    // [15] plot::idx#0 = plots[plot::x#1] -- vbuyy=pbuc1_derefidx_vbuxx 
    ldy plots,x
    // [16] plot::$0 = SCREEN[plot::idx#0] + 1 -- vbuaa=pbuc1_derefidx_vbuyy_plus_1 
    lda SCREEN,y
    clc
    adc #1
    // [17] SCREEN[plot::idx#0] = plot::$0 -- pbuc1_derefidx_vbuyy=vbuaa 
    sta SCREEN,y
    jmp __breturn
    // plot::@return
  __breturn:
    // [18] return 
    rts
}
  // File Data

ASSEMBLER OPTIMIZATIONS
Removing instruction jmp __b1
Removing instruction jmp __b2
Removing instruction jmp __b1
Removing instruction jmp __breturn
Removing instruction jmp __b3
Removing instruction jmp __breturn
Succesful ASM optimization Pass5NextJumpElimination
Replacing label __b1_from___b1 with __b1
Replacing label __b2_from___b2 with __b2
Removing instruction __b1_from___b1:
Removing instruction __b2_from___b1:
Removing instruction __b2_from___b2:
Removing instruction line_from___b2:
Succesful ASM optimization Pass5RedundantLabelElimination
Removing instruction __b1_from_main:
Removing instruction __b1_from_line:
Removing instruction __breturn:
Removing instruction __b3:
Removing instruction __b1_from___b3:
Removing instruction __breturn:
Succesful ASM optimization Pass5UnusedLabelElimination
Removing instruction jmp __b1
Succesful ASM optimization Pass5NextJumpElimination

FINAL SYMBOL TABLE
__constant char * const SCREEN = (char *) 1024
void line(char x0 , char x1)
char line::x
char line::x#1 // reg byte x 20002.0
char line::x#2 // reg byte x 10001.0
char line::x0
__constant char line::x0#0 = 0 // x0
char line::x1
__constant char line::x1#0 = $a // x1
void main()
char main::i
char main::i#1 // reg byte x 16.5
char main::i#2 // reg byte x 18.333333333333332
void plot(char x)
char plot::$0 // reg byte a 200002.0
char plot::idx
char plot::idx#0 // reg byte y 150001.5
char plot::x
char plot::x#1 // reg byte x 110002.0
__constant char * const plots = (char *) 4096

reg byte x [ main::i#2 main::i#1 ]
reg byte x [ line::x#2 line::x#1 ]
reg byte x [ plot::x#1 ]
reg byte y [ plot::idx#0 ]
reg byte a [ plot::$0 ]


FINAL ASSEMBLER
Score: 2013

  // File Comments
  // Upstart
  // Commodore 64 PRG executable file
.file [name="const-identification.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
  .label plots = $1000
  .label SCREEN = $400
.segment Code
  // main
main: {
    // [1] phi from main to main::@1 [phi:main->main::@1]
    // [1] phi main::i#2 = 0 [phi:main->main::@1#0] -- vbuxx=vbuc1 
    ldx #0
    // [1] phi from main::@1 to main::@1 [phi:main::@1->main::@1]
    // [1] phi main::i#2 = main::i#1 [phi:main::@1->main::@1#0] -- register_copy 
    // main::@1
  __b1:
    // plots[i] = i
    // [2] plots[main::i#2] = main::i#2 -- pbuc1_derefidx_vbuxx=vbuxx 
    txa
    sta plots,x
    // SCREEN[i] = 0
    // [3] SCREEN[main::i#2] = 0 -- pbuc1_derefidx_vbuxx=vbuc2 
    lda #0
    sta SCREEN,x
    // for(byte i : 0..39)
    // [4] main::i#1 = ++ main::i#2 -- vbuxx=_inc_vbuxx 
    inx
    // [5] if(main::i#1!=$28) goto main::@1 -- vbuxx_neq_vbuc1_then_la1 
    cpx #$28
    bne __b1
    // [6] phi from main::@1 main::@2 to main::@2 [phi:main::@1/main::@2->main::@2]
    // main::@2
  __b2:
    // line(0, 10)
    // [7] call line
    // [8] phi from main::@2 to line [phi:main::@2->line]
    jsr line
    jmp __b2
}
  // line
// void line(char x0, char x1)
line: {
    .const x0 = 0
    .const x1 = $a
    // [9] phi from line to line::@1 [phi:line->line::@1]
    // [9] phi line::x#2 = line::x0#0 [phi:line->line::@1#0] -- vbuxx=vbuc1 
    ldx #x0
    // line::@1
  __b1:
    // for(byte x = x0; x<=x1; x++)
    // [10] if(line::x#2<line::x1#0+1) goto line::@2 -- vbuxx_lt_vbuc1_then_la1 
    cpx #x1+1
    bcc __b2
    // line::@return
    // }
    // [11] return 
    rts
    // line::@2
  __b2:
    // plot(x)
    // [12] plot::x#1 = line::x#2
    // [13] call plot
    jsr plot
    // line::@3
    // for(byte x = x0; x<=x1; x++)
    // [14] line::x#1 = ++ line::x#2 -- vbuxx=_inc_vbuxx 
    inx
    // [9] phi from line::@3 to line::@1 [phi:line::@3->line::@1]
    // [9] phi line::x#2 = line::x#1 [phi:line::@3->line::@1#0] -- register_copy 
    jmp __b1
}
  // plot
// void plot(__register(X) char x)
plot: {
    // byte idx = plots[x]
    // [15] plot::idx#0 = plots[plot::x#1] -- vbuyy=pbuc1_derefidx_vbuxx 
    ldy plots,x
    // SCREEN[idx]+1
    // [16] plot::$0 = SCREEN[plot::idx#0] + 1 -- vbuaa=pbuc1_derefidx_vbuyy_plus_1 
    lda SCREEN,y
    clc
    adc #1
    // SCREEN[idx] = SCREEN[idx]+1
    // [17] SCREEN[plot::idx#0] = plot::$0 -- pbuc1_derefidx_vbuyy=vbuaa 
    sta SCREEN,y
    // plot::@return
    // }
    // [18] return 
    rts
}
  // File Data