Culled Empty Block (label) malloc::@1

CONTROL FLOW GRAPH SSA
@begin: scope:[]  from
  (byte*) MEM#0 ← ((byte*)) (number) $400
  to:@1

(byte*()) malloc()
malloc: scope:[malloc]  from @1 @3
  (byte*) MEM#5 ← phi( @1/(byte*) MEM#9 @3/(byte*) MEM#3 )
  (byte*) MEM#1 ← ++ (byte*) MEM#5
  (byte*) malloc::return#0 ← (byte*) MEM#1
  to:malloc::@return
malloc::@return: scope:[malloc]  from malloc
  (byte*) MEM#6 ← phi( malloc/(byte*) MEM#1 )
  (byte*) malloc::return#4 ← phi( malloc/(byte*) malloc::return#0 )
  (byte*) malloc::return#1 ← (byte*) malloc::return#4
  (byte*) MEM#2 ← (byte*) MEM#6
  return 
  to:@return
@1: scope:[]  from @begin
  (byte*) MEM#9 ← phi( @begin/(byte*) MEM#0 )
  call malloc 
  (byte*) malloc::return#2 ← (byte*) malloc::return#1
  to:@3
@3: scope:[]  from @1
  (byte*) MEM#7 ← phi( @1/(byte*) MEM#2 )
  (byte*) malloc::return#5 ← phi( @1/(byte*) malloc::return#2 )
  (byte*~) $0 ← (byte*) malloc::return#5
  (byte*) MEM#3 ← (byte*) MEM#7
  (byte*) SCREEN_1#0 ← (byte*~) $0
  call malloc 
  (byte*) malloc::return#3 ← (byte*) malloc::return#1
  to:@4
@4: scope:[]  from @3
  (byte*) SCREEN_1#3 ← phi( @3/(byte*) SCREEN_1#0 )
  (byte*) MEM#8 ← phi( @3/(byte*) MEM#2 )
  (byte*) malloc::return#6 ← phi( @3/(byte*) malloc::return#3 )
  (byte*~) $1 ← (byte*) malloc::return#6
  (byte*) MEM#4 ← (byte*) MEM#8
  (byte*) SCREEN_2#0 ← (byte*~) $1
  to:@2

(void()) main()
main: scope:[main]  from @2
  (byte*) SCREEN_2#1 ← phi( @2/(byte*) SCREEN_2#2 )
  (byte*) SCREEN_1#1 ← phi( @2/(byte*) SCREEN_1#2 )
  *((byte*) SCREEN_1#1) ← (number) 0
  *((byte*) SCREEN_2#1) ← (number) 0
  to:main::@return
main::@return: scope:[main]  from main
  return 
  to:@return
@2: scope:[]  from @4
  (byte*) SCREEN_2#2 ← phi( @4/(byte*) SCREEN_2#0 )
  (byte*) SCREEN_1#2 ← phi( @4/(byte*) SCREEN_1#3 )
  call main 
  to:@5
@5: scope:[]  from @2
  to:@end
@end: scope:[]  from @5

SYMBOL TABLE SSA
(byte*~) $0
(byte*~) $1
(label) @1
(label) @2
(label) @3
(label) @4
(label) @5
(label) @begin
(label) @end
(byte*) MEM
(byte*) MEM#0
(byte*) MEM#1
(byte*) MEM#2
(byte*) MEM#3
(byte*) MEM#4
(byte*) MEM#5
(byte*) MEM#6
(byte*) MEM#7
(byte*) MEM#8
(byte*) MEM#9
(byte*) SCREEN_1
(byte*) SCREEN_1#0
(byte*) SCREEN_1#1
(byte*) SCREEN_1#2
(byte*) SCREEN_1#3
(byte*) SCREEN_2
(byte*) SCREEN_2#0
(byte*) SCREEN_2#1
(byte*) SCREEN_2#2
(void()) main()
(label) main::@return
(byte*()) malloc()
(label) malloc::@return
(byte*) malloc::return
(byte*) malloc::return#0
(byte*) malloc::return#1
(byte*) malloc::return#2
(byte*) malloc::return#3
(byte*) malloc::return#4
(byte*) malloc::return#5
(byte*) malloc::return#6

Adding number conversion cast (unumber) 0 in *((byte*) SCREEN_1#1) ← (number) 0
Adding number conversion cast (unumber) 0 in *((byte*) SCREEN_2#1) ← (number) 0
Successful SSA optimization PassNAddNumberTypeConversions
Inlining cast (byte*) MEM#0 ← (byte*)(number) $400
Inlining cast *((byte*) SCREEN_1#1) ← (unumber)(number) 0
Inlining cast *((byte*) SCREEN_2#1) ← (unumber)(number) 0
Successful SSA optimization Pass2InlineCast
Simplifying constant pointer cast (byte*) 1024
Simplifying constant integer cast 0
Simplifying constant integer cast 0
Successful SSA optimization PassNCastSimplification
Finalized unsigned number type (byte) 0
Finalized unsigned number type (byte) 0
Successful SSA optimization PassNFinalizeNumberTypeConversions
Alias (byte*) malloc::return#0 = (byte*) malloc::return#4 (byte*) malloc::return#1 
Alias (byte*) MEM#1 = (byte*) MEM#6 (byte*) MEM#2 
Alias (byte*) MEM#0 = (byte*) MEM#9 
Alias (byte*) malloc::return#2 = (byte*) malloc::return#5 
Alias (byte*) MEM#3 = (byte*) MEM#7 
Alias (byte*) SCREEN_1#0 = (byte*~) $0 (byte*) SCREEN_1#3 (byte*) SCREEN_1#2 
Alias (byte*) malloc::return#3 = (byte*) malloc::return#6 
Alias (byte*) MEM#4 = (byte*) MEM#8 
Alias (byte*) SCREEN_2#0 = (byte*~) $1 (byte*) SCREEN_2#2 
Successful SSA optimization Pass2AliasElimination
Identical Phi Values (byte*) MEM#3 (byte*) MEM#1
Identical Phi Values (byte*) MEM#4 (byte*) MEM#1
Identical Phi Values (byte*) SCREEN_1#1 (byte*) SCREEN_1#0
Identical Phi Values (byte*) SCREEN_2#1 (byte*) SCREEN_2#0
Successful SSA optimization Pass2IdenticalPhiElimination
Constant (const byte*) MEM#0 = (byte*) 1024
Successful SSA optimization Pass2ConstantIdentification
Inlining constant with var siblings (const byte*) MEM#0
Constant inlined MEM#0 = (byte*) 1024
Successful SSA optimization Pass2ConstantInlining
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 @5
Adding NOP phi() at start of @end
CALL GRAPH
Calls in [] to malloc:2 malloc:6 main:10 

Created 1 initial phi equivalence classes
Coalesced [5] MEM#10 ← MEM#1
Coalesced down to 1 phi equivalence classes
Culled Empty Block (label) @5
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

FINAL CONTROL FLOW GRAPH
@begin: scope:[]  from
  [0] phi()
  to:@1
@1: scope:[]  from @begin
  [1] phi()
  [2] call malloc 
  [3] (byte*) malloc::return#2 ← (byte*) malloc::return#0
  to:@3
@3: scope:[]  from @1
  [4] (byte*) SCREEN_1#0 ← (byte*) malloc::return#2
  [5] call malloc 
  [6] (byte*) malloc::return#3 ← (byte*) malloc::return#0
  to:@4
@4: scope:[]  from @3
  [7] (byte*) SCREEN_2#0 ← (byte*) malloc::return#3
  to:@2
@2: scope:[]  from @4
  [8] phi()
  [9] call main 
  to:@end
@end: scope:[]  from @2
  [10] phi()

(void()) main()
main: scope:[main]  from @2
  [11] *((byte*) SCREEN_1#0) ← (byte) 0
  [12] *((byte*) SCREEN_2#0) ← (byte) 0
  to:main::@return
main::@return: scope:[main]  from main
  [13] return 
  to:@return

(byte*()) malloc()
malloc: scope:[malloc]  from @1 @3
  [14] (byte*) MEM#5 ← phi( @1/(byte*) 1024 @3/(byte*) MEM#1 )
  [15] (byte*) MEM#1 ← ++ (byte*) MEM#5
  [16] (byte*) malloc::return#0 ← (byte*) MEM#1
  to:malloc::@return
malloc::@return: scope:[malloc]  from malloc
  [17] return 
  to:@return


VARIABLE REGISTER WEIGHTS
(byte*) MEM
(byte*) MEM#1 1.0
(byte*) MEM#5 4.0
(byte*) SCREEN_1
(byte*) SCREEN_1#0 0.8
(byte*) SCREEN_2
(byte*) SCREEN_2#0 1.3333333333333333
(void()) main()
(byte*()) malloc()
(byte*) malloc::return
(byte*) malloc::return#0 1.5
(byte*) malloc::return#2 4.0
(byte*) malloc::return#3 4.0

Initial phi equivalence classes
[ MEM#5 MEM#1 ]
Added variable malloc::return#2 to zero page equivalence class [ malloc::return#2 ]
Added variable SCREEN_1#0 to zero page equivalence class [ SCREEN_1#0 ]
Added variable malloc::return#3 to zero page equivalence class [ malloc::return#3 ]
Added variable SCREEN_2#0 to zero page equivalence class [ SCREEN_2#0 ]
Added variable malloc::return#0 to zero page equivalence class [ malloc::return#0 ]
Complete equivalence classes
[ MEM#5 MEM#1 ]
[ malloc::return#2 ]
[ SCREEN_1#0 ]
[ malloc::return#3 ]
[ SCREEN_2#0 ]
[ malloc::return#0 ]
Allocated zp[2]:2 [ MEM#5 MEM#1 ]
Allocated zp[2]:4 [ malloc::return#2 ]
Allocated zp[2]:6 [ SCREEN_1#0 ]
Allocated zp[2]:8 [ malloc::return#3 ]
Allocated zp[2]:10 [ SCREEN_2#0 ]
Allocated zp[2]:12 [ malloc::return#0 ]

INITIAL ASM
Target platform is c64basic / MOS6502X
  // File Comments
// Error where the compiler is reusing the same ZP for two byte* variables.
// SCREEN_1 and SCREEN_2 are both allocated to ZP: 4
// Problem is that outside main() scope statements have zero call-paths and then isStatementAllocationOverlapping() never checks liveranges
// CallPath code must be rewritten to use @begin as the outermost call instead of main()
  // Upstart
.pc = $801 "Basic"
:BasicUpstart(__bbegin)
.pc = $80d "Program"
  // Global Constants & labels
  .label MEM = 2
  .label SCREEN_1 = 6
  .label SCREEN_2 = $a
  // @begin
__bbegin:
  // [1] phi from @begin to @1 [phi:@begin->@1]
__b1_from___bbegin:
  jmp __b1
  // @1
__b1:
  // [2] call malloc 
  // [14] phi from @1 to malloc [phi:@1->malloc]
malloc_from___b1:
  // [14] phi (byte*) MEM#5 = (byte*) 1024 [phi:@1->malloc#0] -- pbuz1=pbuc1 
  lda #<$400
  sta.z MEM
  lda #>$400
  sta.z MEM+1
  jsr malloc
  // [3] (byte*) malloc::return#2 ← (byte*) malloc::return#0 -- pbuz1=pbuz2 
  lda.z malloc.return
  sta.z malloc.return_1
  lda.z malloc.return+1
  sta.z malloc.return_1+1
  jmp __b3
  // @3
__b3:
  // [4] (byte*) SCREEN_1#0 ← (byte*) malloc::return#2 -- pbuz1=pbuz2 
  lda.z malloc.return_1
  sta.z SCREEN_1
  lda.z malloc.return_1+1
  sta.z SCREEN_1+1
  // [5] call malloc 
  // [14] phi from @3 to malloc [phi:@3->malloc]
malloc_from___b3:
  // [14] phi (byte*) MEM#5 = (byte*) MEM#1 [phi:@3->malloc#0] -- register_copy 
  jsr malloc
  // [6] (byte*) malloc::return#3 ← (byte*) malloc::return#0 -- pbuz1=pbuz2 
  lda.z malloc.return
  sta.z malloc.return_2
  lda.z malloc.return+1
  sta.z malloc.return_2+1
  jmp __b4
  // @4
__b4:
  // [7] (byte*) SCREEN_2#0 ← (byte*) malloc::return#3 -- pbuz1=pbuz2 
  lda.z malloc.return_2
  sta.z SCREEN_2
  lda.z malloc.return_2+1
  sta.z SCREEN_2+1
  // [8] phi from @4 to @2 [phi:@4->@2]
__b2_from___b4:
  jmp __b2
  // @2
__b2:
  // [9] call main 
  jsr main
  // [10] phi from @2 to @end [phi:@2->@end]
__bend_from___b2:
  jmp __bend
  // @end
__bend:
  // main
main: {
    // [11] *((byte*) SCREEN_1#0) ← (byte) 0 -- _deref_pbuz1=vbuc1 
    lda #0
    ldy #0
    sta (SCREEN_1),y
    // [12] *((byte*) SCREEN_2#0) ← (byte) 0 -- _deref_pbuz1=vbuc1 
    lda #0
    ldy #0
    sta (SCREEN_2),y
    jmp __breturn
    // main::@return
  __breturn:
    // [13] return 
    rts
}
  // malloc
malloc: {
    .label return = $c
    .label return_1 = 4
    .label return_2 = 8
    // [15] (byte*) MEM#1 ← ++ (byte*) MEM#5 -- pbuz1=_inc_pbuz1 
    inc.z MEM
    bne !+
    inc.z MEM+1
  !:
    // [16] (byte*) malloc::return#0 ← (byte*) MEM#1 -- pbuz1=pbuz2 
    lda.z MEM
    sta.z return
    lda.z MEM+1
    sta.z return+1
    jmp __breturn
    // malloc::@return
  __breturn:
    // [17] return 
    rts
}
  // File Data

REGISTER UPLIFT POTENTIAL REGISTERS
Statement [3] (byte*) malloc::return#2 ← (byte*) malloc::return#0 [ malloc::return#2 MEM#1 ] (  [ malloc::return#2 MEM#1 ] ) always clobbers reg byte a 
Statement [4] (byte*) SCREEN_1#0 ← (byte*) malloc::return#2 [ SCREEN_1#0 MEM#1 ] (  [ SCREEN_1#0 MEM#1 ] ) always clobbers reg byte a 
Statement [6] (byte*) malloc::return#3 ← (byte*) malloc::return#0 [ SCREEN_1#0 malloc::return#3 ] (  [ SCREEN_1#0 malloc::return#3 ] ) always clobbers reg byte a 
Statement [7] (byte*) SCREEN_2#0 ← (byte*) malloc::return#3 [ SCREEN_1#0 SCREEN_2#0 ] (  [ SCREEN_1#0 SCREEN_2#0 ] ) always clobbers reg byte a 
Statement [11] *((byte*) SCREEN_1#0) ← (byte) 0 [ SCREEN_2#0 ] ( main:9 [ SCREEN_2#0 ] ) always clobbers reg byte a reg byte y 
Statement [12] *((byte*) SCREEN_2#0) ← (byte) 0 [ ] ( main:9 [ ] ) always clobbers reg byte a reg byte y 
Statement [16] (byte*) malloc::return#0 ← (byte*) MEM#1 [ malloc::return#0 MEM#1 ] ( malloc:2 [ malloc::return#0 MEM#1 ] malloc:5 [ malloc::return#0 MEM#1 ] ) always clobbers reg byte a 
Potential registers zp[2]:2 [ MEM#5 MEM#1 ] : zp[2]:2 , 
Potential registers zp[2]:4 [ malloc::return#2 ] : zp[2]:4 , 
Potential registers zp[2]:6 [ SCREEN_1#0 ] : zp[2]:6 , 
Potential registers zp[2]:8 [ malloc::return#3 ] : zp[2]:8 , 
Potential registers zp[2]:10 [ SCREEN_2#0 ] : zp[2]:10 , 
Potential registers zp[2]:12 [ malloc::return#0 ] : zp[2]:12 , 

REGISTER UPLIFT SCOPES
Uplift Scope [malloc] 4: zp[2]:4 [ malloc::return#2 ] 4: zp[2]:8 [ malloc::return#3 ] 1.5: zp[2]:12 [ malloc::return#0 ] 
Uplift Scope [] 5: zp[2]:2 [ MEM#5 MEM#1 ] 1.33: zp[2]:10 [ SCREEN_2#0 ] 0.8: zp[2]:6 [ SCREEN_1#0 ] 
Uplift Scope [main] 

Uplifting [malloc] best 153 combination zp[2]:4 [ malloc::return#2 ] zp[2]:8 [ malloc::return#3 ] zp[2]:12 [ malloc::return#0 ] 
Uplifting [] best 153 combination zp[2]:2 [ MEM#5 MEM#1 ] zp[2]:10 [ SCREEN_2#0 ] zp[2]:6 [ SCREEN_1#0 ] 
Uplifting [main] best 153 combination 
Coalescing zero page register [ zp[2]:4 [ malloc::return#2 ] ] with [ zp[2]:6 [ SCREEN_1#0 ] ] - score: 1
Coalescing zero page register [ zp[2]:8 [ malloc::return#3 ] ] with [ zp[2]:10 [ SCREEN_2#0 ] ] - score: 1
Coalescing zero page register [ zp[2]:8 [ malloc::return#3 SCREEN_2#0 ] ] with [ zp[2]:12 [ malloc::return#0 ] ] - score: 1
Allocated (was zp[2]:8) zp[2]:6 [ malloc::return#3 SCREEN_2#0 malloc::return#0 ]

ASSEMBLER BEFORE OPTIMIZATION
  // File Comments
// Error where the compiler is reusing the same ZP for two byte* variables.
// SCREEN_1 and SCREEN_2 are both allocated to ZP: 4
// Problem is that outside main() scope statements have zero call-paths and then isStatementAllocationOverlapping() never checks liveranges
// CallPath code must be rewritten to use @begin as the outermost call instead of main()
  // Upstart
.pc = $801 "Basic"
:BasicUpstart(__bbegin)
.pc = $80d "Program"
  // Global Constants & labels
  .label MEM = 2
  .label SCREEN_1 = 4
  .label SCREEN_2 = 6
  // @begin
__bbegin:
  // [1] phi from @begin to @1 [phi:@begin->@1]
__b1_from___bbegin:
  jmp __b1
  // @1
__b1:
  // [2] call malloc 
  // [14] phi from @1 to malloc [phi:@1->malloc]
malloc_from___b1:
  // [14] phi (byte*) MEM#5 = (byte*) 1024 [phi:@1->malloc#0] -- pbuz1=pbuc1 
  lda #<$400
  sta.z MEM
  lda #>$400
  sta.z MEM+1
  jsr malloc
  // [3] (byte*) malloc::return#2 ← (byte*) malloc::return#0 -- pbuz1=pbuz2 
  lda.z malloc.return
  sta.z malloc.return_1
  lda.z malloc.return+1
  sta.z malloc.return_1+1
  jmp __b3
  // @3
__b3:
  // [4] (byte*) SCREEN_1#0 ← (byte*) malloc::return#2
  // [5] call malloc 
  // [14] phi from @3 to malloc [phi:@3->malloc]
malloc_from___b3:
  // [14] phi (byte*) MEM#5 = (byte*) MEM#1 [phi:@3->malloc#0] -- register_copy 
  jsr malloc
  // [6] (byte*) malloc::return#3 ← (byte*) malloc::return#0
  jmp __b4
  // @4
__b4:
  // [7] (byte*) SCREEN_2#0 ← (byte*) malloc::return#3
  // [8] phi from @4 to @2 [phi:@4->@2]
__b2_from___b4:
  jmp __b2
  // @2
__b2:
  // [9] call main 
  jsr main
  // [10] phi from @2 to @end [phi:@2->@end]
__bend_from___b2:
  jmp __bend
  // @end
__bend:
  // main
main: {
    // [11] *((byte*) SCREEN_1#0) ← (byte) 0 -- _deref_pbuz1=vbuc1 
    lda #0
    ldy #0
    sta (SCREEN_1),y
    // [12] *((byte*) SCREEN_2#0) ← (byte) 0 -- _deref_pbuz1=vbuc1 
    lda #0
    ldy #0
    sta (SCREEN_2),y
    jmp __breturn
    // main::@return
  __breturn:
    // [13] return 
    rts
}
  // malloc
malloc: {
    .label return = 6
    .label return_1 = 4
    // [15] (byte*) MEM#1 ← ++ (byte*) MEM#5 -- pbuz1=_inc_pbuz1 
    inc.z MEM
    bne !+
    inc.z MEM+1
  !:
    // [16] (byte*) malloc::return#0 ← (byte*) MEM#1 -- pbuz1=pbuz2 
    lda.z MEM
    sta.z return
    lda.z MEM+1
    sta.z return+1
    jmp __breturn
    // malloc::@return
  __breturn:
    // [17] return 
    rts
}
  // File Data

ASSEMBLER OPTIMIZATIONS
Removing instruction jmp __b1
Removing instruction jmp __b3
Removing instruction jmp __b4
Removing instruction jmp __b2
Removing instruction jmp __bend
Removing instruction jmp __breturn
Removing instruction jmp __breturn
Succesful ASM optimization Pass5NextJumpElimination
Replacing instruction ldy #0 with TAY
Removing instruction lda #0
Removing instruction ldy #0
Succesful ASM optimization Pass5UnnecesaryLoadElimination
Replacing label __bbegin with __b1
Removing instruction __bbegin:
Removing instruction __b1_from___bbegin:
Removing instruction malloc_from___b1:
Removing instruction malloc_from___b3:
Removing instruction __b4:
Removing instruction __b2_from___b4:
Removing instruction __bend_from___b2:
Succesful ASM optimization Pass5RedundantLabelElimination
Removing instruction __b3:
Removing instruction __b2:
Removing instruction __bend:
Removing instruction __breturn:
Removing instruction __breturn:
Succesful ASM optimization Pass5UnusedLabelElimination
Adding RTS to root block 
Succesful ASM optimization Pass5AddMainRts

FINAL SYMBOL TABLE
(label) @1
(label) @2
(label) @3
(label) @4
(label) @begin
(label) @end
(byte*) MEM
(byte*) MEM#1 MEM zp[2]:2 1.0
(byte*) MEM#5 MEM zp[2]:2 4.0
(byte*) SCREEN_1
(byte*) SCREEN_1#0 SCREEN_1 zp[2]:4 0.8
(byte*) SCREEN_2
(byte*) SCREEN_2#0 SCREEN_2 zp[2]:6 1.3333333333333333
(void()) main()
(label) main::@return
(byte*()) malloc()
(label) malloc::@return
(byte*) malloc::return
(byte*) malloc::return#0 return zp[2]:6 1.5
(byte*) malloc::return#2 return_1 zp[2]:4 4.0
(byte*) malloc::return#3 return zp[2]:6 4.0

zp[2]:2 [ MEM#5 MEM#1 ]
zp[2]:4 [ malloc::return#2 SCREEN_1#0 ]
zp[2]:6 [ malloc::return#3 SCREEN_2#0 malloc::return#0 ]


FINAL ASSEMBLER
Score: 98

  // File Comments
// Error where the compiler is reusing the same ZP for two byte* variables.
// SCREEN_1 and SCREEN_2 are both allocated to ZP: 4
// Problem is that outside main() scope statements have zero call-paths and then isStatementAllocationOverlapping() never checks liveranges
// CallPath code must be rewritten to use @begin as the outermost call instead of main()
  // Upstart
.pc = $801 "Basic"
:BasicUpstart(__b1)
.pc = $80d "Program"
  // Global Constants & labels
  .label MEM = 2
  .label SCREEN_1 = 4
  .label SCREEN_2 = 6
  // @begin
  // [1] phi from @begin to @1 [phi:@begin->@1]
  // @1
__b1:
  // malloc()
  // [2] call malloc 
  // [14] phi from @1 to malloc [phi:@1->malloc]
  // [14] phi (byte*) MEM#5 = (byte*) 1024 [phi:@1->malloc#0] -- pbuz1=pbuc1 
  lda #<$400
  sta.z MEM
  lda #>$400
  sta.z MEM+1
  jsr malloc
  // malloc()
  // [3] (byte*) malloc::return#2 ← (byte*) malloc::return#0 -- pbuz1=pbuz2 
  lda.z malloc.return
  sta.z malloc.return_1
  lda.z malloc.return+1
  sta.z malloc.return_1+1
  // @3
  // SCREEN_1 = malloc()
  // [4] (byte*) SCREEN_1#0 ← (byte*) malloc::return#2
  // malloc()
  // [5] call malloc 
  // [14] phi from @3 to malloc [phi:@3->malloc]
  // [14] phi (byte*) MEM#5 = (byte*) MEM#1 [phi:@3->malloc#0] -- register_copy 
  jsr malloc
  // malloc()
  // [6] (byte*) malloc::return#3 ← (byte*) malloc::return#0
  // @4
  // SCREEN_2 = malloc()
  // [7] (byte*) SCREEN_2#0 ← (byte*) malloc::return#3
  // [8] phi from @4 to @2 [phi:@4->@2]
  // @2
  // [9] call main 
  jsr main
  rts
  // [10] phi from @2 to @end [phi:@2->@end]
  // @end
  // main
main: {
    // *SCREEN_1 = 0
    // [11] *((byte*) SCREEN_1#0) ← (byte) 0 -- _deref_pbuz1=vbuc1 
    lda #0
    tay
    sta (SCREEN_1),y
    // *SCREEN_2 = 0
    // [12] *((byte*) SCREEN_2#0) ← (byte) 0 -- _deref_pbuz1=vbuc1 
    sta (SCREEN_2),y
    // main::@return
    // }
    // [13] return 
    rts
}
  // malloc
malloc: {
    .label return = 6
    .label return_1 = 4
    // return ++MEM;
    // [15] (byte*) MEM#1 ← ++ (byte*) MEM#5 -- pbuz1=_inc_pbuz1 
    inc.z MEM
    bne !+
    inc.z MEM+1
  !:
    // [16] (byte*) malloc::return#0 ← (byte*) MEM#1 -- pbuz1=pbuz2 
    lda.z MEM
    sta.z return
    lda.z MEM+1
    sta.z return+1
    // malloc::@return
    // }
    // [17] return 
    rts
}
  // File Data