Identified constant variable (byte*) SCREEN
Culled Empty Block (label) @1
Culled Empty Block (label) memset::@7
Culled Empty Block (label) memset::@6
Culled Empty Block (label) memset::@8
Culled Empty Block (label) memset::@9
Culled Empty Block (label) memset::@3

CONTROL FLOW GRAPH SSA
@begin: scope:[]  from
  to:@2

(void()) main()
main: scope:[main]  from @2
  (void*) memset::str#0 ← (void*)(const byte*) SCREEN
  (byte) memset::c#0 ← (byte) 'c'
  (word) memset::num#0 ← (number) $3e8
  call memset 
  (void*) memset::return#0 ← (void*) memset::return#2
  to:main::@1
main::@1: scope:[main]  from main
  to:main::@return
main::@return: scope:[main]  from main::@1
  return 
  to:@return

(void*()) memset((void*) memset::str , (byte) memset::c , (word) memset::num)
memset: scope:[memset]  from main
  (byte) memset::c#4 ← phi( main/(byte) memset::c#0 )
  (void*) memset::str#3 ← phi( main/(void*) memset::str#0 )
  (word) memset::num#1 ← phi( main/(word) memset::num#0 )
  (bool~) memset::$0 ← (word) memset::num#1 > (number) 0
  (bool~) memset::$1 ← ! (bool~) memset::$0
  if((bool~) memset::$1) goto memset::@1
  to:memset::@2
memset::@1: scope:[memset]  from memset memset::@4
  (void*) memset::str#1 ← phi( memset/(void*) memset::str#3 memset::@4/(void*) memset::str#4 )
  (void*) memset::return#1 ← (void*) memset::str#1
  to:memset::@return
memset::@2: scope:[memset]  from memset
  (byte) memset::c#3 ← phi( memset/(byte) memset::c#4 )
  (word) memset::num#2 ← phi( memset/(word) memset::num#1 )
  (void*) memset::str#2 ← phi( memset/(void*) memset::str#3 )
  (byte*~) memset::$2 ← ((byte*)) (void*) memset::str#2
  (byte*~) memset::$3 ← (byte*~) memset::$2 + (word) memset::num#2
  (byte*) memset::end#0 ← (byte*~) memset::$3
  (byte*) memset::dst#0 ← ((byte*)) (void*) memset::str#2
  to:memset::@4
memset::@4: scope:[memset]  from memset::@2 memset::@5
  (byte) memset::c#2 ← phi( memset::@2/(byte) memset::c#3 memset::@5/(byte) memset::c#1 )
  (void*) memset::str#4 ← phi( memset::@2/(void*) memset::str#2 memset::@5/(void*) memset::str#5 )
  (byte*) memset::end#1 ← phi( memset::@2/(byte*) memset::end#0 memset::@5/(byte*) memset::end#2 )
  (byte*) memset::dst#2 ← phi( memset::@2/(byte*) memset::dst#0 memset::@5/(byte*) memset::dst#1 )
  (bool~) memset::$4 ← (byte*) memset::dst#2 != (byte*) memset::end#1
  if((bool~) memset::$4) goto memset::@5
  to:memset::@1
memset::@5: scope:[memset]  from memset::@4
  (void*) memset::str#5 ← phi( memset::@4/(void*) memset::str#4 )
  (byte*) memset::end#2 ← phi( memset::@4/(byte*) memset::end#1 )
  (byte*) memset::dst#3 ← phi( memset::@4/(byte*) memset::dst#2 )
  (byte) memset::c#1 ← phi( memset::@4/(byte) memset::c#2 )
  *((byte*) memset::dst#3) ← (byte) memset::c#1
  (byte*) memset::dst#1 ← ++ (byte*) memset::dst#3
  to:memset::@4
memset::@return: scope:[memset]  from memset::@1
  (void*) memset::return#3 ← phi( memset::@1/(void*) memset::return#1 )
  (void*) memset::return#2 ← (void*) memset::return#3
  return 
  to:@return
@2: scope:[]  from @begin
  call main 
  to:@3
@3: scope:[]  from @2
  to:@end
@end: scope:[]  from @3

SYMBOL TABLE SSA
(label) @2
(label) @3
(label) @begin
(label) @end
(const byte*) SCREEN = (byte*)(number) $400
(void()) main()
(label) main::@1
(label) main::@return
(void*()) memset((void*) memset::str , (byte) memset::c , (word) memset::num)
(bool~) memset::$0
(bool~) memset::$1
(byte*~) memset::$2
(byte*~) memset::$3
(bool~) memset::$4
(label) memset::@1
(label) memset::@2
(label) memset::@4
(label) memset::@5
(label) memset::@return
(byte) memset::c
(byte) memset::c#0
(byte) memset::c#1
(byte) memset::c#2
(byte) memset::c#3
(byte) memset::c#4
(byte*) memset::dst
(byte*) memset::dst#0
(byte*) memset::dst#1
(byte*) memset::dst#2
(byte*) memset::dst#3
(byte*) memset::end
(byte*) memset::end#0
(byte*) memset::end#1
(byte*) memset::end#2
(word) memset::num
(word) memset::num#0
(word) memset::num#1
(word) memset::num#2
(void*) memset::return
(void*) memset::return#0
(void*) memset::return#1
(void*) memset::return#2
(void*) memset::return#3
(void*) memset::str
(void*) memset::str#0
(void*) memset::str#1
(void*) memset::str#2
(void*) memset::str#3
(void*) memset::str#4
(void*) memset::str#5

Adding number conversion cast (unumber) $3e8 in (word) memset::num#0 ← (number) $3e8
Adding number conversion cast (unumber) 0 in (bool~) memset::$0 ← (word) memset::num#1 > (number) 0
Successful SSA optimization PassNAddNumberTypeConversions
Inlining cast (word) memset::num#0 ← (unumber)(number) $3e8
Inlining cast (byte*~) memset::$2 ← (byte*)(void*) memset::str#2
Inlining cast (byte*) memset::dst#0 ← (byte*)(void*) memset::str#2
Successful SSA optimization Pass2InlineCast
Simplifying constant pointer cast (byte*) 1024
Simplifying constant integer cast $3e8
Simplifying constant integer cast 0
Successful SSA optimization PassNCastSimplification
Finalized unsigned number type (word) $3e8
Finalized unsigned number type (byte) 0
Successful SSA optimization PassNFinalizeNumberTypeConversions
Inversing boolean not [8] (bool~) memset::$1 ← (word) memset::num#1 <= (byte) 0 from [7] (bool~) memset::$0 ← (word) memset::num#1 > (byte) 0
Successful SSA optimization Pass2UnaryNotSimplification
Alias (void*) memset::return#1 = (void*) memset::str#1 (void*) memset::return#3 (void*) memset::return#2 
Alias (void*) memset::str#2 = (void*) memset::str#3 
Alias (word) memset::num#1 = (word) memset::num#2 
Alias (byte) memset::c#3 = (byte) memset::c#4 
Alias (byte*) memset::end#0 = (byte*~) memset::$3 
Alias (byte) memset::c#1 = (byte) memset::c#2 
Alias (byte*) memset::dst#2 = (byte*) memset::dst#3 
Alias (byte*) memset::end#1 = (byte*) memset::end#2 
Alias (void*) memset::str#4 = (void*) memset::str#5 
Successful SSA optimization Pass2AliasElimination
Identical Phi Values (word) memset::num#1 (word) memset::num#0
Identical Phi Values (void*) memset::str#2 (void*) memset::str#0
Identical Phi Values (byte) memset::c#3 (byte) memset::c#0
Identical Phi Values (byte*) memset::end#1 (byte*) memset::end#0
Identical Phi Values (void*) memset::str#4 (void*) memset::str#2
Identical Phi Values (byte) memset::c#1 (byte) memset::c#3
Successful SSA optimization Pass2IdenticalPhiElimination
Identical Phi Values (void*) memset::return#1 (void*) memset::str#0
Successful SSA optimization Pass2IdenticalPhiElimination
Simple Condition (bool~) memset::$1 [9] if((word) memset::num#0<=(byte) 0) goto memset::@1
Simple Condition (bool~) memset::$4 [19] if((byte*) memset::dst#2!=(byte*) memset::end#0) goto memset::@5
Successful SSA optimization Pass2ConditionalJumpSimplification
Constant right-side identified [0] (void*) memset::str#0 ← (void*)(const byte*) SCREEN
Successful SSA optimization Pass2ConstantRValueConsolidation
Constant (const void*) memset::str#0 = (void*)SCREEN
Constant (const byte) memset::c#0 = 'c'
Constant (const word) memset::num#0 = $3e8
Successful SSA optimization Pass2ConstantIdentification
Constant (const void*) memset::return#0 = memset::str#0
Constant (const byte*) memset::$2 = (byte*)memset::str#0
Constant (const byte*) memset::dst#0 = (byte*)memset::str#0
Successful SSA optimization Pass2ConstantIdentification
if() condition always false - eliminating [9] if((const word) memset::num#0<=(byte) 0) goto memset::@1
Successful SSA optimization Pass2ConstantIfs
Eliminating unused constant (const void*) memset::return#0
Successful SSA optimization PassNEliminateUnusedVars
Constant right-side identified [2] (byte*) memset::end#0 ← (const byte*) memset::$2 + (const word) memset::num#0
Successful SSA optimization Pass2ConstantRValueConsolidation
Constant (const byte*) memset::end#0 = memset::$2+memset::num#0
Successful SSA optimization Pass2ConstantIdentification
Inlining constant with var siblings (const byte*) memset::dst#0
Constant inlined memset::$2 = (byte*)(const void*) memset::str#0
Constant inlined memset::dst#0 = (byte*)(const void*) memset::str#0
Successful SSA optimization Pass2ConstantInlining
Adding NOP phi() at start of @begin
Adding NOP phi() at start of @2
Adding NOP phi() at start of @3
Adding NOP phi() at start of @end
Adding NOP phi() at start of main
Adding NOP phi() at start of main::@1
Adding NOP phi() at start of memset
Adding NOP phi() at start of memset::@2
Adding NOP phi() at start of memset::@1
CALL GRAPH
Calls in [] to main:2 
Calls in [main] to memset:6 

Created 1 initial phi equivalence classes
Coalesced [17] memset::dst#4 ← memset::dst#1
Coalesced down to 1 phi equivalence classes
Culled Empty Block (label) @3
Culled Empty Block (label) main::@1
Culled Empty Block (label) memset::@2
Culled Empty Block (label) memset::@1
Renumbering block @2 to @1
Renumbering block memset::@4 to memset::@1
Renumbering block memset::@5 to memset::@2
Adding NOP phi() at start of @begin
Adding NOP phi() at start of @1
Adding NOP phi() at start of @end
Adding NOP phi() at start of main
Adding NOP phi() at start of memset

FINAL CONTROL FLOW GRAPH
@begin: scope:[]  from
  [0] phi()
  to:@1
@1: scope:[]  from @begin
  [1] phi()
  [2] call main 
  to:@end
@end: scope:[]  from @1
  [3] phi()

(void()) main()
main: scope:[main]  from @1
  [4] phi()
  [5] call memset 
  to:main::@return
main::@return: scope:[main]  from main
  [6] return 
  to:@return

(void*()) memset((void*) memset::str , (byte) memset::c , (word) memset::num)
memset: scope:[memset]  from main
  [7] phi()
  to:memset::@1
memset::@1: scope:[memset]  from memset memset::@2
  [8] (byte*) memset::dst#2 ← phi( memset/(byte*)(const void*) memset::str#0 memset::@2/(byte*) memset::dst#1 )
  [9] if((byte*) memset::dst#2!=(const byte*) memset::end#0) goto memset::@2
  to:memset::@return
memset::@return: scope:[memset]  from memset::@1
  [10] return 
  to:@return
memset::@2: scope:[memset]  from memset::@1
  [11] *((byte*) memset::dst#2) ← (const byte) memset::c#0
  [12] (byte*) memset::dst#1 ← ++ (byte*) memset::dst#2
  to:memset::@1


VARIABLE REGISTER WEIGHTS
(void()) main()
(void*()) memset((void*) memset::str , (byte) memset::c , (word) memset::num)
(byte) memset::c
(byte*) memset::dst
(byte*) memset::dst#1 22.0
(byte*) memset::dst#2 14.666666666666666
(byte*) memset::end
(word) memset::num
(void*) memset::return
(void*) memset::str

Initial phi equivalence classes
[ memset::dst#2 memset::dst#1 ]
Complete equivalence classes
[ memset::dst#2 memset::dst#1 ]
Allocated zp[2]:2 [ memset::dst#2 memset::dst#1 ]

INITIAL ASM
Target platform is c64basic / MOS6502X
  // File Comments
// Minimal classic for() loop - coded using while() to test optimization of loop heads
  // Upstart
.pc = $801 "Basic"
:BasicUpstart(__bbegin)
.pc = $80d "Program"
  // Global Constants & labels
  .label SCREEN = $400
  // @begin
__bbegin:
  // [1] phi from @begin to @1 [phi:@begin->@1]
__b1_from___bbegin:
  jmp __b1
  // @1
__b1:
  // [2] call main 
  // [4] phi from @1 to main [phi:@1->main]
main_from___b1:
  jsr main
  // [3] phi from @1 to @end [phi:@1->@end]
__bend_from___b1:
  jmp __bend
  // @end
__bend:
  // main
main: {
    // [5] call memset 
    // [7] phi from main to memset [phi:main->memset]
  memset_from_main:
    jsr memset
    jmp __breturn
    // main::@return
  __breturn:
    // [6] return 
    rts
}
  // memset
// Copies the character c (an unsigned char) to the first num characters of the object pointed to by the argument str.
memset: {
    .label str = SCREEN
    .const c = 'c'
    .const num = $3e8
    .label end = str+num
    .label dst = 2
    // [8] phi from memset to memset::@1 [phi:memset->memset::@1]
  __b1_from_memset:
    // [8] phi (byte*) memset::dst#2 = (byte*)(const void*) memset::str#0 [phi:memset->memset::@1#0] -- pbuz1=pbuc1 
    lda #<str
    sta.z dst
    lda #>str
    sta.z dst+1
    jmp __b1
    // memset::@1
  __b1:
    // [9] if((byte*) memset::dst#2!=(const byte*) memset::end#0) goto memset::@2 -- pbuz1_neq_pbuc1_then_la1 
    lda.z dst+1
    cmp #>end
    bne __b2
    lda.z dst
    cmp #<end
    bne __b2
    jmp __breturn
    // memset::@return
  __breturn:
    // [10] return 
    rts
    // memset::@2
  __b2:
    // [11] *((byte*) memset::dst#2) ← (const byte) memset::c#0 -- _deref_pbuz1=vbuc1 
    lda #c
    ldy #0
    sta (dst),y
    // [12] (byte*) memset::dst#1 ← ++ (byte*) memset::dst#2 -- pbuz1=_inc_pbuz1 
    inc.z dst
    bne !+
    inc.z dst+1
  !:
    // [8] phi from memset::@2 to memset::@1 [phi:memset::@2->memset::@1]
  __b1_from___b2:
    // [8] phi (byte*) memset::dst#2 = (byte*) memset::dst#1 [phi:memset::@2->memset::@1#0] -- register_copy 
    jmp __b1
}
  // File Data

REGISTER UPLIFT POTENTIAL REGISTERS
Statement [9] if((byte*) memset::dst#2!=(const byte*) memset::end#0) goto memset::@2 [ memset::dst#2 ] ( main:2::memset:5 [ memset::dst#2 ] ) always clobbers reg byte a 
Statement [11] *((byte*) memset::dst#2) ← (const byte) memset::c#0 [ memset::dst#2 ] ( main:2::memset:5 [ memset::dst#2 ] ) always clobbers reg byte a reg byte y 
Potential registers zp[2]:2 [ memset::dst#2 memset::dst#1 ] : zp[2]:2 , 

REGISTER UPLIFT SCOPES
Uplift Scope [memset] 36.67: zp[2]:2 [ memset::dst#2 memset::dst#1 ] 
Uplift Scope [main] 
Uplift Scope [] 

Uplifting [memset] best 598 combination zp[2]:2 [ memset::dst#2 memset::dst#1 ] 
Uplifting [main] best 598 combination 
Uplifting [] best 598 combination 

ASSEMBLER BEFORE OPTIMIZATION
  // File Comments
// Minimal classic for() loop - coded using while() to test optimization of loop heads
  // Upstart
.pc = $801 "Basic"
:BasicUpstart(__bbegin)
.pc = $80d "Program"
  // Global Constants & labels
  .label SCREEN = $400
  // @begin
__bbegin:
  // [1] phi from @begin to @1 [phi:@begin->@1]
__b1_from___bbegin:
  jmp __b1
  // @1
__b1:
  // [2] call main 
  // [4] phi from @1 to main [phi:@1->main]
main_from___b1:
  jsr main
  // [3] phi from @1 to @end [phi:@1->@end]
__bend_from___b1:
  jmp __bend
  // @end
__bend:
  // main
main: {
    // [5] call memset 
    // [7] phi from main to memset [phi:main->memset]
  memset_from_main:
    jsr memset
    jmp __breturn
    // main::@return
  __breturn:
    // [6] return 
    rts
}
  // memset
// Copies the character c (an unsigned char) to the first num characters of the object pointed to by the argument str.
memset: {
    .label str = SCREEN
    .const c = 'c'
    .const num = $3e8
    .label end = str+num
    .label dst = 2
    // [8] phi from memset to memset::@1 [phi:memset->memset::@1]
  __b1_from_memset:
    // [8] phi (byte*) memset::dst#2 = (byte*)(const void*) memset::str#0 [phi:memset->memset::@1#0] -- pbuz1=pbuc1 
    lda #<str
    sta.z dst
    lda #>str
    sta.z dst+1
    jmp __b1
    // memset::@1
  __b1:
    // [9] if((byte*) memset::dst#2!=(const byte*) memset::end#0) goto memset::@2 -- pbuz1_neq_pbuc1_then_la1 
    lda.z dst+1
    cmp #>end
    bne __b2
    lda.z dst
    cmp #<end
    bne __b2
    jmp __breturn
    // memset::@return
  __breturn:
    // [10] return 
    rts
    // memset::@2
  __b2:
    // [11] *((byte*) memset::dst#2) ← (const byte) memset::c#0 -- _deref_pbuz1=vbuc1 
    lda #c
    ldy #0
    sta (dst),y
    // [12] (byte*) memset::dst#1 ← ++ (byte*) memset::dst#2 -- pbuz1=_inc_pbuz1 
    inc.z dst
    bne !+
    inc.z dst+1
  !:
    // [8] phi from memset::@2 to memset::@1 [phi:memset::@2->memset::@1]
  __b1_from___b2:
    // [8] phi (byte*) memset::dst#2 = (byte*) memset::dst#1 [phi:memset::@2->memset::@1#0] -- register_copy 
    jmp __b1
}
  // File Data

ASSEMBLER OPTIMIZATIONS
Removing instruction jmp __b1
Removing instruction jmp __bend
Removing instruction jmp __breturn
Removing instruction jmp __b1
Removing instruction jmp __breturn
Succesful ASM optimization Pass5NextJumpElimination
Replacing label __bbegin with __b1
Removing instruction __bbegin:
Removing instruction __b1_from___bbegin:
Removing instruction main_from___b1:
Removing instruction __bend_from___b1:
Succesful ASM optimization Pass5RedundantLabelElimination
Removing instruction __bend:
Removing instruction memset_from_main:
Removing instruction __breturn:
Removing instruction __b1_from_memset:
Removing instruction __breturn:
Removing instruction __b1_from___b2:
Succesful ASM optimization Pass5UnusedLabelElimination
Updating BasicUpstart to call main directly
Removing instruction jsr main
Succesful ASM optimization Pass5SkipBegin
Removing instruction __b1:
Succesful ASM optimization Pass5UnusedLabelElimination

FINAL SYMBOL TABLE
(label) @1
(label) @begin
(label) @end
(const byte*) SCREEN = (byte*) 1024
(void()) main()
(label) main::@return
(void*()) memset((void*) memset::str , (byte) memset::c , (word) memset::num)
(label) memset::@1
(label) memset::@2
(label) memset::@return
(byte) memset::c
(const byte) memset::c#0 c = (byte) 'c'
(byte*) memset::dst
(byte*) memset::dst#1 dst zp[2]:2 22.0
(byte*) memset::dst#2 dst zp[2]:2 14.666666666666666
(byte*) memset::end
(const byte*) memset::end#0 end = (byte*)(const void*) memset::str#0+(const word) memset::num#0
(word) memset::num
(const word) memset::num#0 num = (word) $3e8
(void*) memset::return
(void*) memset::str
(const void*) memset::str#0 str = (void*)(const byte*) SCREEN

zp[2]:2 [ memset::dst#2 memset::dst#1 ]


FINAL ASSEMBLER
Score: 523

  // File Comments
// Minimal classic for() loop - coded using while() to test optimization of loop heads
  // Upstart
.pc = $801 "Basic"
:BasicUpstart(main)
.pc = $80d "Program"
  // Global Constants & labels
  .label SCREEN = $400
  // @begin
  // [1] phi from @begin to @1 [phi:@begin->@1]
  // @1
  // [2] call main 
  // [4] phi from @1 to main [phi:@1->main]
  // [3] phi from @1 to @end [phi:@1->@end]
  // @end
  // main
main: {
    // memset(SCREEN, 'c', 1000)
    // [5] call memset 
    // [7] phi from main to memset [phi:main->memset]
    jsr memset
    // main::@return
    // }
    // [6] return 
    rts
}
  // memset
// Copies the character c (an unsigned char) to the first num characters of the object pointed to by the argument str.
memset: {
    .label str = SCREEN
    .const c = 'c'
    .const num = $3e8
    .label end = str+num
    .label dst = 2
    // [8] phi from memset to memset::@1 [phi:memset->memset::@1]
    // [8] phi (byte*) memset::dst#2 = (byte*)(const void*) memset::str#0 [phi:memset->memset::@1#0] -- pbuz1=pbuc1 
    lda #<str
    sta.z dst
    lda #>str
    sta.z dst+1
    // memset::@1
  __b1:
    // while(dst!=end)
    // [9] if((byte*) memset::dst#2!=(const byte*) memset::end#0) goto memset::@2 -- pbuz1_neq_pbuc1_then_la1 
    lda.z dst+1
    cmp #>end
    bne __b2
    lda.z dst
    cmp #<end
    bne __b2
    // memset::@return
    // }
    // [10] return 
    rts
    // memset::@2
  __b2:
    // *dst = c
    // [11] *((byte*) memset::dst#2) ← (const byte) memset::c#0 -- _deref_pbuz1=vbuc1 
    lda #c
    ldy #0
    sta (dst),y
    // dst++;
    // [12] (byte*) memset::dst#1 ← ++ (byte*) memset::dst#2 -- pbuz1=_inc_pbuz1 
    inc.z dst
    bne !+
    inc.z dst+1
  !:
    // [8] phi from memset::@2 to memset::@1 [phi:memset::@2->memset::@1]
    // [8] phi (byte*) memset::dst#2 = (byte*) memset::dst#1 [phi:memset::@2->memset::@1#0] -- register_copy 
    jmp __b1
}
  // File Data

