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
main: scope:[main]  from @1
  (byte*) main::SCREEN#0 ← ((byte*)) (number) $400
  (byte*~) main::$0 ← (byte*) main::SCREEN#0 + (number) $27
  (byte*) main::sc#0 ← (byte*~) main::$0
  (byte) main::i#0 ← (number) 0
  to:main::@1
main::@1: scope:[main]  from main main::@2
  (byte*) main::sc#3 ← phi( main/(byte*) main::sc#0 main::@2/(byte*) main::sc#1 )
  (byte) main::i#2 ← phi( main/(byte) main::i#0 main::@2/(byte) main::i#1 )
  (bool~) main::$1 ← (byte) main::i#2 < (number) $28
  if((bool~) main::$1) goto main::@2
  to:main::@return
main::@2: scope:[main]  from main::@1
  (byte*) main::sc#2 ← phi( main::@1/(byte*) main::sc#3 )
  (byte) main::i#3 ← phi( main::@1/(byte) main::i#2 )
  *((byte*) main::sc#2) ← (byte) main::i#3
  (byte) main::i#1 ← ++ (byte) main::i#3
  (byte*) main::sc#1 ← -- (byte*) main::sc#2
  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()
(byte*~) main::$0
(bool~) main::$1
(label) main::@1
(label) main::@2
(label) main::@return
(byte*) main::SCREEN
(byte*) main::SCREEN#0
(byte) main::i
(byte) main::i#0
(byte) main::i#1
(byte) main::i#2
(byte) main::i#3
(byte*) main::sc
(byte*) main::sc#0
(byte*) main::sc#1
(byte*) main::sc#2
(byte*) main::sc#3

Adding number conversion cast (unumber) $27 in (byte*~) main::$0 ← (byte*) main::SCREEN#0 + (number) $27
Adding number conversion cast (unumber) 0 in (byte) main::i#0 ← (number) 0
Adding number conversion cast (unumber) $28 in (bool~) main::$1 ← (byte) main::i#2 < (number) $28
Successful SSA optimization PassNAddNumberTypeConversions
Inlining cast (byte*) main::SCREEN#0 ← (byte*)(number) $400
Inlining cast (byte) main::i#0 ← (unumber)(number) 0
Successful SSA optimization Pass2InlineCast
Simplifying constant pointer cast (byte*) 1024
Simplifying constant integer cast $27
Simplifying constant integer cast 0
Simplifying constant integer cast $28
Successful SSA optimization PassNCastSimplification
Finalized unsigned number type (byte) $27
Finalized unsigned number type (byte) 0
Finalized unsigned number type (byte) $28
Successful SSA optimization PassNFinalizeNumberTypeConversions
Alias (byte*) main::sc#0 = (byte*~) main::$0 
Alias (byte) main::i#2 = (byte) main::i#3 
Alias (byte*) main::sc#2 = (byte*) main::sc#3 
Successful SSA optimization Pass2AliasElimination
Simple Condition (bool~) main::$1 [6] if((byte) main::i#2<(byte) $28) goto main::@2
Successful SSA optimization Pass2ConditionalJumpSimplification
Constant (const byte*) main::SCREEN#0 = (byte*) 1024
Constant (const byte) main::i#0 = 0
Successful SSA optimization Pass2ConstantIdentification
Successful SSA optimization Pass2LoopHeadConstantIdentification
Alias (byte) main::i#1 = (byte) main::i#2 
Alias (byte*) main::sc#1 = (byte*) main::sc#2 
Alias (byte*) main::sc#0 = (byte*) main::sc#5 
Successful SSA optimization Pass2AliasElimination
Identical Phi Values (byte) main::i#5 (const byte) main::i#0
Successful SSA optimization Pass2IdenticalPhiElimination
Constant right-side identified [0] (byte*) main::sc#0 ← (const byte*) main::SCREEN#0 + (byte) $27
Successful SSA optimization Pass2ConstantRValueConsolidation
Constant (const byte*) main::sc#0 = main::SCREEN#0+$27
Successful SSA optimization Pass2ConstantIdentification
if() condition always true - replacing block destination [11] if((const byte) main::i#0<(byte) $28) goto main::@2
Successful SSA optimization Pass2ConstantIfs
Inlining constant with var siblings (const byte) main::i#0
Inlining constant with var siblings (const byte*) main::sc#0
Constant inlined main::i#0 = (byte) 0
Constant inlined main::sc#0 = (const byte*) main::SCREEN#0+(byte) $27
Successful SSA optimization Pass2ConstantInlining
Added new block during phi lifting main::@7(between main::@1 and main::@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
Adding NOP phi() at start of main::@1_1
CALL GRAPH
Calls in [] to main:2 

Created 2 initial phi equivalence classes
Coalesced [13] main::i#6 ← main::i#1
Coalesced [14] main::sc#6 ← main::sc#1
Coalesced down to 2 phi equivalence classes
Culled Empty Block (label) @2
Culled Empty Block (label) main::@1_1
Culled Empty Block (label) main::@7
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()
main: scope:[main]  from @1
  [4] phi()
  to:main::@2
main::@2: scope:[main]  from main main::@1
  [5] (byte*) main::sc#4 ← phi( main::@1/(byte*) main::sc#1 main/(const byte*) main::SCREEN#0+(byte) $27 )
  [5] (byte) main::i#4 ← phi( main::@1/(byte) main::i#1 main/(byte) 0 )
  [6] *((byte*) main::sc#4) ← (byte) main::i#4
  [7] (byte) main::i#1 ← ++ (byte) main::i#4
  [8] (byte*) main::sc#1 ← -- (byte*) main::sc#4
  to:main::@1
main::@1: scope:[main]  from main::@2
  [9] if((byte) main::i#1<(byte) $28) goto main::@2
  to:main::@return
main::@return: scope:[main]  from main::@1
  [10] return 
  to:@return


VARIABLE REGISTER WEIGHTS
(void()) main()
(byte*) main::SCREEN
(byte) main::i
(byte) main::i#1 11.0
(byte) main::i#4 16.5
(byte*) main::sc
(byte*) main::sc#1 11.0
(byte*) main::sc#4 11.0

Initial phi equivalence classes
[ main::i#4 main::i#1 ]
[ main::sc#4 main::sc#1 ]
Complete equivalence classes
[ main::i#4 main::i#1 ]
[ main::sc#4 main::sc#1 ]
Allocated zp ZP_BYTE:2 [ main::i#4 main::i#1 ]
Allocated zp ZP_WORD:3 [ main::sc#4 main::sc#1 ]

INITIAL ASM
Target platform is c64basic
  // File Comments
// Test a for-loop with two iterating variables
// Illustrates that for()-loops currently cannot contain two variable declarations.
  // 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 i = 2
    .label sc = 3
    // [5] phi from main to main::@2 [phi:main->main::@2]
  b2_from_main:
    // [5] phi (byte*) main::sc#4 = (const byte*) main::SCREEN#0+(byte) $27 [phi:main->main::@2#0] -- pbuz1=pbuc1 
    lda #<SCREEN+$27
    sta.z sc
    lda #>SCREEN+$27
    sta.z sc+1
    // [5] phi (byte) main::i#4 = (byte) 0 [phi:main->main::@2#1] -- vbuz1=vbuc1 
    lda #0
    sta.z i
    jmp b2
    // [5] phi from main::@1 to main::@2 [phi:main::@1->main::@2]
  b2_from_b1:
    // [5] phi (byte*) main::sc#4 = (byte*) main::sc#1 [phi:main::@1->main::@2#0] -- register_copy 
    // [5] phi (byte) main::i#4 = (byte) main::i#1 [phi:main::@1->main::@2#1] -- register_copy 
    jmp b2
    // main::@2
  b2:
    // [6] *((byte*) main::sc#4) ← (byte) main::i#4 -- _deref_pbuz1=vbuz2 
    lda.z i
    ldy #0
    sta (sc),y
    // [7] (byte) main::i#1 ← ++ (byte) main::i#4 -- vbuz1=_inc_vbuz1 
    inc.z i
    // [8] (byte*) main::sc#1 ← -- (byte*) main::sc#4 -- pbuz1=_dec_pbuz1 
    lda.z sc
    bne !+
    dec.z sc+1
  !:
    dec.z sc
    jmp b1
    // main::@1
  b1:
    // [9] if((byte) main::i#1<(byte) $28) goto main::@2 -- vbuz1_lt_vbuc1_then_la1 
    lda.z i
    cmp #$28
    bcc b2_from_b1
    jmp breturn
    // main::@return
  breturn:
    // [10] return 
    rts
}
  // File Data

REGISTER UPLIFT POTENTIAL REGISTERS
Statement [6] *((byte*) main::sc#4) ← (byte) main::i#4 [ main::i#4 main::sc#4 ] ( main:2 [ main::i#4 main::sc#4 ] ) always clobbers reg byte y 
Removing always clobbered register reg byte y as potential for zp ZP_BYTE:2 [ main::i#4 main::i#1 ]
Statement [8] (byte*) main::sc#1 ← -- (byte*) main::sc#4 [ main::i#1 main::sc#1 ] ( main:2 [ main::i#1 main::sc#1 ] ) always clobbers reg byte a 
Removing always clobbered register reg byte a as potential for zp ZP_BYTE:2 [ main::i#4 main::i#1 ]
Statement [6] *((byte*) main::sc#4) ← (byte) main::i#4 [ main::i#4 main::sc#4 ] ( main:2 [ main::i#4 main::sc#4 ] ) always clobbers reg byte a reg byte y 
Statement [8] (byte*) main::sc#1 ← -- (byte*) main::sc#4 [ main::i#1 main::sc#1 ] ( main:2 [ main::i#1 main::sc#1 ] ) always clobbers reg byte a 
Potential registers zp ZP_BYTE:2 [ main::i#4 main::i#1 ] : zp ZP_BYTE:2 , reg byte x , 
Potential registers zp ZP_WORD:3 [ main::sc#4 main::sc#1 ] : zp ZP_WORD:3 , 

REGISTER UPLIFT SCOPES
Uplift Scope [main] 27.5: zp ZP_BYTE:2 [ main::i#4 main::i#1 ] 22: zp ZP_WORD:3 [ main::sc#4 main::sc#1 ] 
Uplift Scope [] 

Uplifting [main] best 578 combination reg byte x [ main::i#4 main::i#1 ] zp ZP_WORD:3 [ main::sc#4 main::sc#1 ] 
Uplifting [] best 578 combination 
Allocated (was zp ZP_WORD:3) zp ZP_WORD:2 [ main::sc#4 main::sc#1 ]

ASSEMBLER BEFORE OPTIMIZATION
  // File Comments
// Test a for-loop with two iterating variables
// Illustrates that for()-loops currently cannot contain two variable declarations.
  // 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 sc = 2
    // [5] phi from main to main::@2 [phi:main->main::@2]
  b2_from_main:
    // [5] phi (byte*) main::sc#4 = (const byte*) main::SCREEN#0+(byte) $27 [phi:main->main::@2#0] -- pbuz1=pbuc1 
    lda #<SCREEN+$27
    sta.z sc
    lda #>SCREEN+$27
    sta.z sc+1
    // [5] phi (byte) main::i#4 = (byte) 0 [phi:main->main::@2#1] -- vbuxx=vbuc1 
    ldx #0
    jmp b2
    // [5] phi from main::@1 to main::@2 [phi:main::@1->main::@2]
  b2_from_b1:
    // [5] phi (byte*) main::sc#4 = (byte*) main::sc#1 [phi:main::@1->main::@2#0] -- register_copy 
    // [5] phi (byte) main::i#4 = (byte) main::i#1 [phi:main::@1->main::@2#1] -- register_copy 
    jmp b2
    // main::@2
  b2:
    // [6] *((byte*) main::sc#4) ← (byte) main::i#4 -- _deref_pbuz1=vbuxx 
    txa
    ldy #0
    sta (sc),y
    // [7] (byte) main::i#1 ← ++ (byte) main::i#4 -- vbuxx=_inc_vbuxx 
    inx
    // [8] (byte*) main::sc#1 ← -- (byte*) main::sc#4 -- pbuz1=_dec_pbuz1 
    lda.z sc
    bne !+
    dec.z sc+1
  !:
    dec.z sc
    jmp b1
    // main::@1
  b1:
    // [9] if((byte) main::i#1<(byte) $28) goto main::@2 -- vbuxx_lt_vbuc1_then_la1 
    cpx #$28
    bcc b2_from_b1
    jmp breturn
    // main::@return
  breturn:
    // [10] return 
    rts
}
  // File Data

ASSEMBLER OPTIMIZATIONS
Removing instruction jmp b1
Removing instruction jmp bend
Removing instruction jmp b2
Removing instruction jmp b1
Removing instruction jmp breturn
Succesful ASM optimization Pass5NextJumpElimination
Replacing label b2_from_b1 with b2
Removing instruction b1_from_bbegin:
Removing instruction b1:
Removing instruction main_from_b1:
Removing instruction bend_from_b1:
Removing instruction b2_from_b1:
Succesful ASM optimization Pass5RedundantLabelElimination
Removing instruction bend:
Removing instruction b2_from_main:
Removing instruction b1:
Removing instruction breturn:
Succesful ASM optimization Pass5UnusedLabelElimination
Updating BasicUpstart to call main directly
Removing instruction jsr main
Succesful ASM optimization Pass5SkipBegin
Removing instruction jmp b2
Succesful ASM optimization Pass5NextJumpElimination
Removing instruction bbegin:
Succesful ASM optimization Pass5UnusedLabelElimination

FINAL SYMBOL TABLE
(label) @1
(label) @begin
(label) @end
(void()) main()
(label) main::@1
(label) main::@2
(label) main::@return
(byte*) main::SCREEN
(const byte*) main::SCREEN#0 SCREEN = (byte*) 1024
(byte) main::i
(byte) main::i#1 reg byte x 11.0
(byte) main::i#4 reg byte x 16.5
(byte*) main::sc
(byte*) main::sc#1 sc zp ZP_WORD:2 11.0
(byte*) main::sc#4 sc zp ZP_WORD:2 11.0

reg byte x [ main::i#4 main::i#1 ]
zp ZP_WORD:2 [ main::sc#4 main::sc#1 ]


FINAL ASSEMBLER
Score: 446

  // File Comments
// Test a for-loop with two iterating variables
// Illustrates that for()-loops currently cannot contain two variable declarations.
  // 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 sc = 2
    // [5] phi from main to main::@2 [phi:main->main::@2]
    // [5] phi (byte*) main::sc#4 = (const byte*) main::SCREEN#0+(byte) $27 [phi:main->main::@2#0] -- pbuz1=pbuc1 
    lda #<SCREEN+$27
    sta.z sc
    lda #>SCREEN+$27
    sta.z sc+1
    // [5] phi (byte) main::i#4 = (byte) 0 [phi:main->main::@2#1] -- vbuxx=vbuc1 
    ldx #0
    // [5] phi from main::@1 to main::@2 [phi:main::@1->main::@2]
    // [5] phi (byte*) main::sc#4 = (byte*) main::sc#1 [phi:main::@1->main::@2#0] -- register_copy 
    // [5] phi (byte) main::i#4 = (byte) main::i#1 [phi:main::@1->main::@2#1] -- register_copy 
    // main::@2
  b2:
    // *sc = i
    // [6] *((byte*) main::sc#4) ← (byte) main::i#4 -- _deref_pbuz1=vbuxx 
    txa
    ldy #0
    sta (sc),y
    // for( byte i=0; i<40; i++, sc--)
    // [7] (byte) main::i#1 ← ++ (byte) main::i#4 -- vbuxx=_inc_vbuxx 
    inx
    // [8] (byte*) main::sc#1 ← -- (byte*) main::sc#4 -- pbuz1=_dec_pbuz1 
    lda.z sc
    bne !+
    dec.z sc+1
  !:
    dec.z sc
    // main::@1
    // [9] if((byte) main::i#1<(byte) $28) goto main::@2 -- vbuxx_lt_vbuc1_then_la1 
    cpx #$28
    bcc b2
    // main::@return
    // }
    // [10] return 
    rts
}
  // File Data

