Identified constant variable (byte*) main::screen
Culled Empty Block (label) main::@4
Culled Empty Block (label) main::@3
Culled Empty Block (label) main::@5
Culled Empty Block (label) main::@6

CONTROL FLOW GRAPH SSA
@begin: scope:[]  from
  to:@1

(void()) main()
main: scope:[main]  from @1
  (signed word) main::lasti#0 ← (signed word) -1
  (signed word) main::i#0 ← (signed word) 0
  to:main::@1
main::@1: scope:[main]  from main main::@2
  (signed word) main::lasti#3 ← phi( main/(signed word) main::lasti#0 main::@2/(signed word) main::lasti#1 )
  (signed word) main::i#2 ← phi( main/(signed word) main::i#0 main::@2/(signed word) main::i#1 )
  (bool~) main::$0 ← (signed word) main::i#2 < (number) $a
  if((bool~) main::$0) goto main::@2
  to:main::@return
main::@2: scope:[main]  from main::@1
  (signed word) main::i#3 ← phi( main::@1/(signed word) main::i#2 )
  (signed word) main::lasti#2 ← phi( main::@1/(signed word) main::lasti#3 )
  (byte~) main::$1 ← < (signed word) main::lasti#2
  *((const byte*) main::screen + (signed word) main::i#3) ← (byte~) main::$1
  (signed word) main::lasti#1 ← (signed word) main::i#3
  (signed word) main::i#1 ← ++ (signed word) main::i#3
  to:main::@1
main::@return: scope:[main]  from main::@1
  return 
  to:@return
@1: scope:[]  from @begin
  call main 
  to:@2
@2: scope:[]  from @1
  to:@end
@end: scope:[]  from @2

SYMBOL TABLE SSA
(label) @1
(label) @2
(label) @begin
(label) @end
(void()) main()
(bool~) main::$0
(byte~) main::$1
(label) main::@1
(label) main::@2
(label) main::@return
(signed word) main::i
(signed word) main::i#0
(signed word) main::i#1
(signed word) main::i#2
(signed word) main::i#3
(signed word) main::lasti
(signed word) main::lasti#0
(signed word) main::lasti#1
(signed word) main::lasti#2
(signed word) main::lasti#3
(const byte*) main::screen = (byte*)(number) $400

Adding number conversion cast (snumber) $a in (bool~) main::$0 ← (signed word) main::i#2 < (number) $a
Successful SSA optimization PassNAddNumberTypeConversions
Simplifying constant pointer cast (byte*) 1024
Simplifying constant integer cast $a
Successful SSA optimization PassNCastSimplification
Finalized signed number type (signed byte) $a
Successful SSA optimization PassNFinalizeNumberTypeConversions
Alias candidate removed (phi-usage) (signed word) main::i#2 = (signed word) main::i#3 (signed word) main::lasti#1 
Alias (signed word) main::lasti#2 = (signed word) main::lasti#3 
Successful SSA optimization Pass2AliasElimination
Alias candidate removed (phi-usage) (signed word) main::i#2 = (signed word) main::i#3 (signed word) main::lasti#1 
Identical Phi Values (signed word) main::i#3 (signed word) main::i#2
Successful SSA optimization Pass2IdenticalPhiElimination
Simple Condition (bool~) main::$0 [4] if((signed word) main::i#2<(signed byte) $a) goto main::@2
Successful SSA optimization Pass2ConditionalJumpSimplification
Constant (const signed word) main::lasti#0 = -1
Constant (const signed word) main::i#0 = 0
Successful SSA optimization Pass2ConstantIdentification
De-inlining pointer[w] to *(pointer+w)   [7] *((const byte*) main::screen + (signed word) main::i#2) ← (byte~) main::$1
Successful SSA optimization Pass2DeInlineWordDerefIdx
Alias candidate removed (phi-usage) (signed word) main::lasti#1 = (signed word) main::i#2 
Inlining constant with var siblings (const signed word) main::lasti#0
Inlining constant with var siblings (const signed word) main::i#0
Constant inlined main::i#0 = (signed word) 0
Constant inlined main::lasti#0 = (signed word) -1
Successful SSA optimization Pass2ConstantInlining
Alias candidate removed (phi-usage) (signed word) main::lasti#1 = (signed word) main::i#2 
Alias candidate removed (phi-usage) (signed word) main::lasti#1 = (signed word) main::i#2 
Adding NOP phi() at start of @begin
Adding NOP phi() at start of @1
Adding NOP phi() at start of @2
Adding NOP phi() at start of @end
Adding NOP phi() at start of main
CALL GRAPH
Calls in [] to main:2 

Created 2 initial phi equivalence classes
Coalesced [14] main::i#4 ← main::i#1
Coalesced [15] main::lasti#4 ← main::lasti#1
Coalesced down to 2 phi equivalence classes
Culled Empty Block (label) @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

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()
  to:main::@1
main::@1: scope:[main]  from main main::@2
  [5] (signed word) main::lasti#2 ← phi( main/(signed word) -1 main::@2/(signed word) main::lasti#1 )
  [5] (signed word) main::i#2 ← phi( main/(signed word) 0 main::@2/(signed word) main::i#1 )
  [6] if((signed word) main::i#2<(signed byte) $a) goto main::@2
  to:main::@return
main::@return: scope:[main]  from main::@1
  [7] return 
  to:@return
main::@2: scope:[main]  from main::@1
  [8] (byte~) main::$1 ← < (signed word) main::lasti#2
  [9] (byte*~) main::$2 ← (const byte*) main::screen + (signed word) main::i#2
  [10] *((byte*~) main::$2) ← (byte~) main::$1
  [11] (signed word) main::lasti#1 ← (signed word) main::i#2
  [12] (signed word) main::i#1 ← ++ (signed word) main::i#2
  to:main::@1


VARIABLE REGISTER WEIGHTS
(void()) main()
(byte~) main::$1 11.0
(byte*~) main::$2 22.0
(signed word) main::i
(signed word) main::i#1 22.0
(signed word) main::i#2 9.166666666666666
(signed word) main::lasti
(signed word) main::lasti#1 11.0
(signed word) main::lasti#2 11.0

Initial phi equivalence classes
[ main::i#2 main::i#1 ]
[ main::lasti#2 main::lasti#1 ]
Added variable main::$1 to live range equivalence class [ main::$1 ]
Added variable main::$2 to live range equivalence class [ main::$2 ]
Complete equivalence classes
[ main::i#2 main::i#1 ]
[ main::lasti#2 main::lasti#1 ]
[ main::$1 ]
[ main::$2 ]
Allocated zp[2]:2 [ main::i#2 main::i#1 ]
Allocated zp[2]:4 [ main::lasti#2 main::lasti#1 ]
Allocated zp[1]:6 [ main::$1 ]
Allocated zp[2]:7 [ main::$2 ]

INITIAL ASM
Target platform is c64basic / MOS6502X
  // File Comments
// https://gitlab.com/camelot/kickc/issues/336
// ASM Static Register Value analysis erronously believes >-1 == 0
  // Upstart
.pc = $801 "Basic"
:BasicUpstart(__bbegin)
.pc = $80d "Program"
  // Global Constants & labels
  // @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: {
    .label screen = $400
    .label __1 = 6
    .label lasti = 4
    .label i = 2
    .label __2 = 7
    // [5] phi from main to main::@1 [phi:main->main::@1]
  __b1_from_main:
    // [5] phi (signed word) main::lasti#2 = (signed word) -1 [phi:main->main::@1#0] -- vwsz1=vwsc1 
    lda #<-1
    sta.z lasti
    lda #>-1
    sta.z lasti+1
    // [5] phi (signed word) main::i#2 = (signed word) 0 [phi:main->main::@1#1] -- vwsz1=vwsc1 
    lda #<0
    sta.z i
    lda #>0
    sta.z i+1
    jmp __b1
    // main::@1
  __b1:
    // [6] if((signed word) main::i#2<(signed byte) $a) goto main::@2 -- vwsz1_lt_vwuc1_then_la1 
    lda.z i+1
    bmi __b2
    cmp #>$a
    bcc __b2
    bne !+
    lda.z i
    cmp #<$a
    bcc __b2
  !:
    jmp __breturn
    // main::@return
  __breturn:
    // [7] return 
    rts
    // main::@2
  __b2:
    // [8] (byte~) main::$1 ← < (signed word) main::lasti#2 -- vbuz1=_lo_vwsz2 
    lda.z lasti
    sta.z __1
    // [9] (byte*~) main::$2 ← (const byte*) main::screen + (signed word) main::i#2 -- pbuz1=pbuc1_plus_vwsz2 
    lda #<screen
    clc
    adc.z i
    sta.z __2
    lda #>screen
    adc.z i+1
    sta.z __2+1
    // [10] *((byte*~) main::$2) ← (byte~) main::$1 -- _deref_pbuz1=vbuz2 
    lda.z __1
    ldy #0
    sta (__2),y
    // [11] (signed word) main::lasti#1 ← (signed word) main::i#2 -- vwsz1=vwsz2 
    lda.z i
    sta.z lasti
    lda.z i+1
    sta.z lasti+1
    // [12] (signed word) main::i#1 ← ++ (signed word) main::i#2 -- vwsz1=_inc_vwsz1 
    inc.z i
    bne !+
    inc.z i+1
  !:
    // [5] phi from main::@2 to main::@1 [phi:main::@2->main::@1]
  __b1_from___b2:
    // [5] phi (signed word) main::lasti#2 = (signed word) main::lasti#1 [phi:main::@2->main::@1#0] -- register_copy 
    // [5] phi (signed word) main::i#2 = (signed word) main::i#1 [phi:main::@2->main::@1#1] -- register_copy 
    jmp __b1
}
  // File Data

REGISTER UPLIFT POTENTIAL REGISTERS
Statement [6] if((signed word) main::i#2<(signed byte) $a) goto main::@2 [ main::i#2 main::lasti#2 ] ( main:2 [ main::i#2 main::lasti#2 ] ) always clobbers reg byte a 
Statement [8] (byte~) main::$1 ← < (signed word) main::lasti#2 [ main::i#2 main::$1 ] ( main:2 [ main::i#2 main::$1 ] ) always clobbers reg byte a 
Statement [9] (byte*~) main::$2 ← (const byte*) main::screen + (signed word) main::i#2 [ main::i#2 main::$1 main::$2 ] ( main:2 [ main::i#2 main::$1 main::$2 ] ) always clobbers reg byte a 
Removing always clobbered register reg byte a as potential for zp[1]:6 [ main::$1 ]
Statement [10] *((byte*~) main::$2) ← (byte~) main::$1 [ main::i#2 ] ( main:2 [ main::i#2 ] ) always clobbers reg byte a reg byte y 
Statement [11] (signed word) main::lasti#1 ← (signed word) main::i#2 [ main::i#2 main::lasti#1 ] ( main:2 [ main::i#2 main::lasti#1 ] ) always clobbers reg byte a 
Statement [6] if((signed word) main::i#2<(signed byte) $a) goto main::@2 [ main::i#2 main::lasti#2 ] ( main:2 [ main::i#2 main::lasti#2 ] ) always clobbers reg byte a 
Statement [8] (byte~) main::$1 ← < (signed word) main::lasti#2 [ main::i#2 main::$1 ] ( main:2 [ main::i#2 main::$1 ] ) always clobbers reg byte a 
Statement [9] (byte*~) main::$2 ← (const byte*) main::screen + (signed word) main::i#2 [ main::i#2 main::$1 main::$2 ] ( main:2 [ main::i#2 main::$1 main::$2 ] ) always clobbers reg byte a 
Statement [10] *((byte*~) main::$2) ← (byte~) main::$1 [ main::i#2 ] ( main:2 [ main::i#2 ] ) always clobbers reg byte a reg byte y 
Statement [11] (signed word) main::lasti#1 ← (signed word) main::i#2 [ main::i#2 main::lasti#1 ] ( main:2 [ main::i#2 main::lasti#1 ] ) always clobbers reg byte a 
Potential registers zp[2]:2 [ main::i#2 main::i#1 ] : zp[2]:2 , 
Potential registers zp[2]:4 [ main::lasti#2 main::lasti#1 ] : zp[2]:4 , 
Potential registers zp[1]:6 [ main::$1 ] : zp[1]:6 , reg byte x , reg byte y , 
Potential registers zp[2]:7 [ main::$2 ] : zp[2]:7 , 

REGISTER UPLIFT SCOPES
Uplift Scope [main] 31.17: zp[2]:2 [ main::i#2 main::i#1 ] 22: zp[2]:4 [ main::lasti#2 main::lasti#1 ] 22: zp[2]:7 [ main::$2 ] 11: zp[1]:6 [ main::$1 ] 
Uplift Scope [] 

Uplifting [main] best 1083 combination zp[2]:2 [ main::i#2 main::i#1 ] zp[2]:4 [ main::lasti#2 main::lasti#1 ] zp[2]:7 [ main::$2 ] reg byte x [ main::$1 ] 
Uplifting [] best 1083 combination 
Allocated (was zp[2]:7) zp[2]:6 [ main::$2 ]

ASSEMBLER BEFORE OPTIMIZATION
  // File Comments
// https://gitlab.com/camelot/kickc/issues/336
// ASM Static Register Value analysis erronously believes >-1 == 0
  // Upstart
.pc = $801 "Basic"
:BasicUpstart(__bbegin)
.pc = $80d "Program"
  // Global Constants & labels
  // @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: {
    .label screen = $400
    .label lasti = 4
    .label i = 2
    .label __2 = 6
    // [5] phi from main to main::@1 [phi:main->main::@1]
  __b1_from_main:
    // [5] phi (signed word) main::lasti#2 = (signed word) -1 [phi:main->main::@1#0] -- vwsz1=vwsc1 
    lda #<-1
    sta.z lasti
    lda #>-1
    sta.z lasti+1
    // [5] phi (signed word) main::i#2 = (signed word) 0 [phi:main->main::@1#1] -- vwsz1=vwsc1 
    lda #<0
    sta.z i
    lda #>0
    sta.z i+1
    jmp __b1
    // main::@1
  __b1:
    // [6] if((signed word) main::i#2<(signed byte) $a) goto main::@2 -- vwsz1_lt_vwuc1_then_la1 
    lda.z i+1
    bmi __b2
    cmp #>$a
    bcc __b2
    bne !+
    lda.z i
    cmp #<$a
    bcc __b2
  !:
    jmp __breturn
    // main::@return
  __breturn:
    // [7] return 
    rts
    // main::@2
  __b2:
    // [8] (byte~) main::$1 ← < (signed word) main::lasti#2 -- vbuxx=_lo_vwsz1 
    lda.z lasti
    tax
    // [9] (byte*~) main::$2 ← (const byte*) main::screen + (signed word) main::i#2 -- pbuz1=pbuc1_plus_vwsz2 
    lda #<screen
    clc
    adc.z i
    sta.z __2
    lda #>screen
    adc.z i+1
    sta.z __2+1
    // [10] *((byte*~) main::$2) ← (byte~) main::$1 -- _deref_pbuz1=vbuxx 
    txa
    ldy #0
    sta (__2),y
    // [11] (signed word) main::lasti#1 ← (signed word) main::i#2 -- vwsz1=vwsz2 
    lda.z i
    sta.z lasti
    lda.z i+1
    sta.z lasti+1
    // [12] (signed word) main::i#1 ← ++ (signed word) main::i#2 -- vwsz1=_inc_vwsz1 
    inc.z i
    bne !+
    inc.z i+1
  !:
    // [5] phi from main::@2 to main::@1 [phi:main::@2->main::@1]
  __b1_from___b2:
    // [5] phi (signed word) main::lasti#2 = (signed word) main::lasti#1 [phi:main::@2->main::@1#0] -- register_copy 
    // [5] phi (signed word) main::i#2 = (signed word) main::i#1 [phi:main::@2->main::@1#1] -- register_copy 
    jmp __b1
}
  // File Data

ASSEMBLER OPTIMIZATIONS
Removing instruction jmp __b1
Removing instruction jmp __bend
Removing instruction jmp __b1
Removing instruction jmp __breturn
Succesful ASM optimization Pass5NextJumpElimination
Removing instruction lda #>-1
Removing instruction lda #>0
Succesful ASM optimization Pass5UnnecesaryLoadElimination
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 __b1_from_main:
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
(void()) main()
(byte~) main::$1 reg byte x 11.0
(byte*~) main::$2 zp[2]:6 22.0
(label) main::@1
(label) main::@2
(label) main::@return
(signed word) main::i
(signed word) main::i#1 i zp[2]:2 22.0
(signed word) main::i#2 i zp[2]:2 9.166666666666666
(signed word) main::lasti
(signed word) main::lasti#1 lasti zp[2]:4 11.0
(signed word) main::lasti#2 lasti zp[2]:4 11.0
(const byte*) main::screen = (byte*) 1024

zp[2]:2 [ main::i#2 main::i#1 ]
zp[2]:4 [ main::lasti#2 main::lasti#1 ]
reg byte x [ main::$1 ]
zp[2]:6 [ main::$2 ]


FINAL ASSEMBLER
Score: 971

  // File Comments
// https://gitlab.com/camelot/kickc/issues/336
// ASM Static Register Value analysis erronously believes >-1 == 0
  // Upstart
.pc = $801 "Basic"
:BasicUpstart(main)
.pc = $80d "Program"
  // Global Constants & labels
  // @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: {
    .label screen = $400
    .label lasti = 4
    .label i = 2
    .label __2 = 6
    // [5] phi from main to main::@1 [phi:main->main::@1]
    // [5] phi (signed word) main::lasti#2 = (signed word) -1 [phi:main->main::@1#0] -- vwsz1=vwsc1 
    lda #<-1
    sta.z lasti
    sta.z lasti+1
    // [5] phi (signed word) main::i#2 = (signed word) 0 [phi:main->main::@1#1] -- vwsz1=vwsc1 
    lda #<0
    sta.z i
    sta.z i+1
    // main::@1
  __b1:
    // for(int i=0;i<10;i++)
    // [6] if((signed word) main::i#2<(signed byte) $a) goto main::@2 -- vwsz1_lt_vwuc1_then_la1 
    lda.z i+1
    bmi __b2
    cmp #>$a
    bcc __b2
    bne !+
    lda.z i
    cmp #<$a
    bcc __b2
  !:
    // main::@return
    // }
    // [7] return 
    rts
    // main::@2
  __b2:
    // <lasti
    // [8] (byte~) main::$1 ← < (signed word) main::lasti#2 -- vbuxx=_lo_vwsz1 
    lda.z lasti
    tax
    // screen[i] = <lasti
    // [9] (byte*~) main::$2 ← (const byte*) main::screen + (signed word) main::i#2 -- pbuz1=pbuc1_plus_vwsz2 
    lda #<screen
    clc
    adc.z i
    sta.z __2
    lda #>screen
    adc.z i+1
    sta.z __2+1
    // [10] *((byte*~) main::$2) ← (byte~) main::$1 -- _deref_pbuz1=vbuxx 
    txa
    ldy #0
    sta (__2),y
    // lasti = i
    // [11] (signed word) main::lasti#1 ← (signed word) main::i#2 -- vwsz1=vwsz2 
    lda.z i
    sta.z lasti
    lda.z i+1
    sta.z lasti+1
    // for(int i=0;i<10;i++)
    // [12] (signed word) main::i#1 ← ++ (signed word) main::i#2 -- vwsz1=_inc_vwsz1 
    inc.z i
    bne !+
    inc.z i+1
  !:
    // [5] phi from main::@2 to main::@1 [phi:main::@2->main::@1]
    // [5] phi (signed word) main::lasti#2 = (signed word) main::lasti#1 [phi:main::@2->main::@1#0] -- register_copy 
    // [5] phi (signed word) main::i#2 = (signed word) main::i#1 [phi:main::@2->main::@1#1] -- register_copy 
    jmp __b1
}
  // File Data

