Culled Empty Block (label) @1
Culled Empty Block (label) first::@1

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

(void()) main()
main: scope:[main]  from @2
  (byte*) first::msg#0 ← (const byte*) msg1
  call first 
  (byte*) first::return#0 ← (byte*) first::return#3
  to:main::@1
main::@1: scope:[main]  from main
  (byte*) first::return#4 ← phi( main/(byte*) first::return#0 )
  (byte*~) main::$0 ← (byte*) first::return#4
  (byte*~) main::$1 ← (byte*~) main::$0 + (number) 0
  *((const byte*) main::SCREEN + (number) 0) ← *((byte*~) main::$1)
  (byte*) first::msg#1 ← (const byte*) msg2
  call first 
  (byte*) first::return#1 ← (byte*) first::return#3
  to:main::@2
main::@2: scope:[main]  from main::@1
  (byte*) first::return#5 ← phi( main::@1/(byte*) first::return#1 )
  (byte*~) main::$2 ← (byte*) first::return#5
  (byte*~) main::$3 ← (byte*~) main::$2 + (number) 0
  *((const byte*) main::SCREEN + (number) 1) ← *((byte*~) main::$3)
  to:main::@return
main::@return: scope:[main]  from main::@2
  return 
  to:@return

(byte*()) first((byte*) first::msg)
first: scope:[first]  from main main::@1
  (byte*) first::msg#2 ← phi( main/(byte*) first::msg#0 main::@1/(byte*) first::msg#1 )
  (byte*~) first::$0 ← (byte*) first::msg#2 + (number) 0
  (byte*~) first::$1 ← ((byte*)) (byte*~) first::$0
  (byte*) first::return#2 ← (byte*~) first::$1
  to:first::@return
first::@return: scope:[first]  from first
  (byte*) first::return#6 ← phi( first/(byte*) first::return#2 )
  (byte*) first::return#3 ← (byte*) first::return#6
  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
(byte*()) first((byte*) first::msg)
(byte*~) first::$0
(byte*~) first::$1
(label) first::@return
(byte*) first::msg
(byte*) first::msg#0
(byte*) first::msg#1
(byte*) first::msg#2
(byte*) first::return
(byte*) first::return#0
(byte*) first::return#1
(byte*) first::return#2
(byte*) first::return#3
(byte*) first::return#4
(byte*) first::return#5
(byte*) first::return#6
(void()) main()
(byte*~) main::$0
(byte*~) main::$1
(byte*~) main::$2
(byte*~) main::$3
(label) main::@1
(label) main::@2
(label) main::@return
(const byte*) main::SCREEN = (byte*)(number) $400
(const byte*) msg1[]  = (byte*) "hello world!"
(const byte*) msg2[]  = (byte*) "goodbye sky?"

Adding number conversion cast (unumber) 0 in (byte*~) main::$1 ← (byte*~) main::$0 + (number) 0
Adding number conversion cast (unumber) 0 in *((const byte*) main::SCREEN + (number) 0) ← *((byte*~) main::$1)
Adding number conversion cast (unumber) 0 in (byte*~) main::$3 ← (byte*~) main::$2 + (number) 0
Adding number conversion cast (unumber) 1 in *((const byte*) main::SCREEN + (number) 1) ← *((byte*~) main::$3)
Adding number conversion cast (unumber) 0 in (byte*~) first::$0 ← (byte*) first::msg#2 + (number) 0
Successful SSA optimization PassNAddNumberTypeConversions
Inlining cast (byte*~) first::$1 ← (byte*)(byte*~) first::$0
Successful SSA optimization Pass2InlineCast
Simplifying constant pointer cast (byte*) 1024
Simplifying constant integer cast 0
Simplifying constant integer cast 0
Simplifying constant integer cast 0
Simplifying constant integer cast 1
Simplifying constant integer cast 0
Simplifying constant integer cast (byte*~) first::$0
Successful SSA optimization PassNCastSimplification
Finalized unsigned number type (byte) 0
Finalized unsigned number type (byte) 0
Finalized unsigned number type (byte) 0
Finalized unsigned number type (byte) 1
Finalized unsigned number type (byte) 0
Successful SSA optimization PassNFinalizeNumberTypeConversions
Alias (byte*) first::return#0 = (byte*) first::return#4 
Alias (byte*) first::return#1 = (byte*) first::return#5 
Alias (byte*) first::return#2 = (byte*~) first::$1 (byte*~) first::$0 (byte*) first::return#6 (byte*) first::return#3 
Successful SSA optimization Pass2AliasElimination
Constant (const byte*) first::msg#0 = msg1
Constant (const byte*) first::msg#1 = msg2
Successful SSA optimization Pass2ConstantIdentification
Converting *(pointer+n) to pointer[n] [5] *((const byte*) main::SCREEN + (byte) 0) ← *((byte*~) main::$1)  -- *(main::$0 + 0)
Converting *(pointer+n) to pointer[n] [11] *((const byte*) main::SCREEN + (byte) 1) ← *((byte*~) main::$3)  -- *(main::$2 + 0)
Successful SSA optimization Pass2InlineDerefIdx
Simplifying expression containing zero main::$0 in [4] (byte*~) main::$1 ← (byte*~) main::$0 + (byte) 0
Simplifying expression containing zero main::$0 in [5] *((const byte*) main::SCREEN + (byte) 0) ← *((byte*~) main::$0 + (byte) 0)
Simplifying expression containing zero main::SCREEN in [5] *((const byte*) main::SCREEN + (byte) 0) ← *((byte*~) main::$0)
Simplifying expression containing zero main::$2 in [10] (byte*~) main::$3 ← (byte*~) main::$2 + (byte) 0
Simplifying expression containing zero main::$2 in [11] *((const byte*) main::SCREEN + (byte) 1) ← *((byte*~) main::$2 + (byte) 0)
Simplifying expression containing zero first::msg#2 in [14] (byte*) first::return#2 ← (byte*) first::msg#2 + (byte) 0
Successful SSA optimization PassNSimplifyExpressionWithZero
Eliminating unused variable (byte*~) main::$1 and assignment [3] (byte*~) main::$1 ← (byte*~) main::$0
Eliminating unused variable (byte*~) main::$3 and assignment [8] (byte*~) main::$3 ← (byte*~) main::$2
Successful SSA optimization PassNEliminateUnusedVars
Alias (byte*) first::return#2 = (byte*) first::msg#2 
Successful SSA optimization Pass2AliasElimination
Constant inlined first::msg#0 = (const byte*) msg1
Constant inlined first::msg#1 = (const byte*) msg2
Successful SSA optimization Pass2ConstantInlining
Consolidated array index constant in *(main::SCREEN+1)
Successful SSA optimization Pass2ConstantAdditionElimination
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
CALL GRAPH
Calls in [] to main:2 
Calls in [main] to first:6 first:10 

Created 1 initial phi equivalence classes
Coalesced down to 1 phi equivalence classes
Culled Empty Block (label) @3
Renumbering block @2 to @1
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()
  [5] call first 
  [6] (byte*) first::return#0 ← (byte*) first::return#2
  to:main::@1
main::@1: scope:[main]  from main
  [7] (byte*~) main::$0 ← (byte*) first::return#0
  [8] *((const byte*) main::SCREEN) ← *((byte*~) main::$0)
  [9] call first 
  [10] (byte*) first::return#1 ← (byte*) first::return#2
  to:main::@2
main::@2: scope:[main]  from main::@1
  [11] (byte*~) main::$2 ← (byte*) first::return#1
  [12] *((const byte*) main::SCREEN+(byte) 1) ← *((byte*~) main::$2)
  to:main::@return
main::@return: scope:[main]  from main::@2
  [13] return 
  to:@return

(byte*()) first((byte*) first::msg)
first: scope:[first]  from main main::@1
  [14] (byte*) first::return#2 ← phi( main/(const byte*) msg1 main::@1/(const byte*) msg2 )
  to:first::@return
first::@return: scope:[first]  from first
  [15] return 
  to:@return


VARIABLE REGISTER WEIGHTS
(byte*()) first((byte*) first::msg)
(byte*) first::msg
(byte*) first::return
(byte*) first::return#0 4.0
(byte*) first::return#1 4.0
(byte*) first::return#2 1.0
(void()) main()
(byte*~) main::$0 4.0
(byte*~) main::$2 4.0

Initial phi equivalence classes
[ first::return#2 ]
Added variable first::return#0 to live range equivalence class [ first::return#0 ]
Added variable main::$0 to live range equivalence class [ main::$0 ]
Added variable first::return#1 to live range equivalence class [ first::return#1 ]
Added variable main::$2 to live range equivalence class [ main::$2 ]
Complete equivalence classes
[ first::return#2 ]
[ first::return#0 ]
[ main::$0 ]
[ first::return#1 ]
[ main::$2 ]
Allocated zp[2]:2 [ first::return#2 ]
Allocated zp[2]:4 [ first::return#0 ]
Allocated zp[2]:6 [ main::$0 ]
Allocated zp[2]:8 [ first::return#1 ]
Allocated zp[2]:10 [ main::$2 ]

INITIAL ASM
Target platform is c64basic / MOS6502X
  // File Comments
// Tests pointer plus 0 elimination
  // 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 __0 = 6
    .label __2 = $a
    // [5] call first 
    // [14] phi from main to first [phi:main->first]
  first_from_main:
    // [14] phi (byte*) first::return#2 = (const byte*) msg1 [phi:main->first#0] -- pbuz1=pbuc1 
    lda #<msg1
    sta.z first.return_2
    lda #>msg1
    sta.z first.return_2+1
    jsr first
    // [6] (byte*) first::return#0 ← (byte*) first::return#2 -- pbuz1=pbuz2 
    lda.z first.return_2
    sta.z first.return
    lda.z first.return_2+1
    sta.z first.return+1
    jmp __b1
    // main::@1
  __b1:
    // [7] (byte*~) main::$0 ← (byte*) first::return#0 -- pbuz1=pbuz2 
    lda.z first.return
    sta.z __0
    lda.z first.return+1
    sta.z __0+1
    // [8] *((const byte*) main::SCREEN) ← *((byte*~) main::$0) -- _deref_pbuc1=_deref_pbuz1 
    ldy #0
    lda (__0),y
    sta SCREEN
    // [9] call first 
    // [14] phi from main::@1 to first [phi:main::@1->first]
  first_from___b1:
    // [14] phi (byte*) first::return#2 = (const byte*) msg2 [phi:main::@1->first#0] -- pbuz1=pbuc1 
    lda #<msg2
    sta.z first.return_2
    lda #>msg2
    sta.z first.return_2+1
    jsr first
    // [10] (byte*) first::return#1 ← (byte*) first::return#2 -- pbuz1=pbuz2 
    lda.z first.return_2
    sta.z first.return_1
    lda.z first.return_2+1
    sta.z first.return_1+1
    jmp __b2
    // main::@2
  __b2:
    // [11] (byte*~) main::$2 ← (byte*) first::return#1 -- pbuz1=pbuz2 
    lda.z first.return_1
    sta.z __2
    lda.z first.return_1+1
    sta.z __2+1
    // [12] *((const byte*) main::SCREEN+(byte) 1) ← *((byte*~) main::$2) -- _deref_pbuc1=_deref_pbuz1 
    ldy #0
    lda (__2),y
    sta SCREEN+1
    jmp __breturn
    // main::@return
  __breturn:
    // [13] return 
    rts
}
  // first
first: {
    .label return = 4
    .label return_1 = 8
    .label return_2 = 2
    jmp __breturn
    // first::@return
  __breturn:
    // [15] return 
    rts
}
  // File Data
  msg1: .text "hello world!"
  .byte 0
  msg2: .text "goodbye sky?"
  .byte 0

REGISTER UPLIFT POTENTIAL REGISTERS
Statement [6] (byte*) first::return#0 ← (byte*) first::return#2 [ first::return#0 ] ( main:2 [ first::return#0 ] ) always clobbers reg byte a 
Statement [7] (byte*~) main::$0 ← (byte*) first::return#0 [ main::$0 ] ( main:2 [ main::$0 ] ) always clobbers reg byte a 
Statement [8] *((const byte*) main::SCREEN) ← *((byte*~) main::$0) [ ] ( main:2 [ ] ) always clobbers reg byte a reg byte y 
Statement [10] (byte*) first::return#1 ← (byte*) first::return#2 [ first::return#1 ] ( main:2 [ first::return#1 ] ) always clobbers reg byte a 
Statement [11] (byte*~) main::$2 ← (byte*) first::return#1 [ main::$2 ] ( main:2 [ main::$2 ] ) always clobbers reg byte a 
Statement [12] *((const byte*) main::SCREEN+(byte) 1) ← *((byte*~) main::$2) [ ] ( main:2 [ ] ) always clobbers reg byte a reg byte y 
Potential registers zp[2]:2 [ first::return#2 ] : zp[2]:2 , 
Potential registers zp[2]:4 [ first::return#0 ] : zp[2]:4 , 
Potential registers zp[2]:6 [ main::$0 ] : zp[2]:6 , 
Potential registers zp[2]:8 [ first::return#1 ] : zp[2]:8 , 
Potential registers zp[2]:10 [ main::$2 ] : zp[2]:10 , 

REGISTER UPLIFT SCOPES
Uplift Scope [first] 4: zp[2]:4 [ first::return#0 ] 4: zp[2]:8 [ first::return#1 ] 1: zp[2]:2 [ first::return#2 ] 
Uplift Scope [main] 4: zp[2]:6 [ main::$0 ] 4: zp[2]:10 [ main::$2 ] 
Uplift Scope [] 

Uplifting [first] best 165 combination zp[2]:4 [ first::return#0 ] zp[2]:8 [ first::return#1 ] zp[2]:2 [ first::return#2 ] 
Uplifting [main] best 165 combination zp[2]:6 [ main::$0 ] zp[2]:10 [ main::$2 ] 
Uplifting [] best 165 combination 
Coalescing zero page register [ zp[2]:2 [ first::return#2 ] ] with [ zp[2]:4 [ first::return#0 ] ] - score: 1
Coalescing zero page register [ zp[2]:2 [ first::return#2 first::return#0 ] ] with [ zp[2]:8 [ first::return#1 ] ] - score: 1
Coalescing zero page register [ zp[2]:2 [ first::return#2 first::return#0 first::return#1 ] ] with [ zp[2]:6 [ main::$0 ] ] - score: 1
Coalescing zero page register [ zp[2]:2 [ first::return#2 first::return#0 first::return#1 main::$0 ] ] with [ zp[2]:10 [ main::$2 ] ] - score: 1

ASSEMBLER BEFORE OPTIMIZATION
  // File Comments
// Tests pointer plus 0 elimination
  // 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 __0 = 2
    .label __2 = 2
    // [5] call first 
    // [14] phi from main to first [phi:main->first]
  first_from_main:
    // [14] phi (byte*) first::return#2 = (const byte*) msg1 [phi:main->first#0] -- pbuz1=pbuc1 
    lda #<msg1
    sta.z first.return
    lda #>msg1
    sta.z first.return+1
    jsr first
    // [6] (byte*) first::return#0 ← (byte*) first::return#2
    jmp __b1
    // main::@1
  __b1:
    // [7] (byte*~) main::$0 ← (byte*) first::return#0
    // [8] *((const byte*) main::SCREEN) ← *((byte*~) main::$0) -- _deref_pbuc1=_deref_pbuz1 
    ldy #0
    lda (__0),y
    sta SCREEN
    // [9] call first 
    // [14] phi from main::@1 to first [phi:main::@1->first]
  first_from___b1:
    // [14] phi (byte*) first::return#2 = (const byte*) msg2 [phi:main::@1->first#0] -- pbuz1=pbuc1 
    lda #<msg2
    sta.z first.return
    lda #>msg2
    sta.z first.return+1
    jsr first
    // [10] (byte*) first::return#1 ← (byte*) first::return#2
    jmp __b2
    // main::@2
  __b2:
    // [11] (byte*~) main::$2 ← (byte*) first::return#1
    // [12] *((const byte*) main::SCREEN+(byte) 1) ← *((byte*~) main::$2) -- _deref_pbuc1=_deref_pbuz1 
    ldy #0
    lda (__2),y
    sta SCREEN+1
    jmp __breturn
    // main::@return
  __breturn:
    // [13] return 
    rts
}
  // first
first: {
    .label return = 2
    jmp __breturn
    // first::@return
  __breturn:
    // [15] return 
    rts
}
  // File Data
  msg1: .text "hello world!"
  .byte 0
  msg2: .text "goodbye sky?"
  .byte 0

ASSEMBLER OPTIMIZATIONS
Removing instruction jmp __b1
Removing instruction jmp __bend
Removing instruction jmp __b1
Removing instruction jmp __b2
Removing instruction jmp __breturn
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 first_from_main:
Removing instruction __b1:
Removing instruction first_from___b1:
Removing instruction __b2:
Removing instruction __breturn:
Removing instruction __breturn:
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
(byte*()) first((byte*) first::msg)
(label) first::@return
(byte*) first::msg
(byte*) first::return
(byte*) first::return#0 return zp[2]:2 4.0
(byte*) first::return#1 return zp[2]:2 4.0
(byte*) first::return#2 return zp[2]:2 1.0
(void()) main()
(byte*~) main::$0 zp[2]:2 4.0
(byte*~) main::$2 zp[2]:2 4.0
(label) main::@1
(label) main::@2
(label) main::@return
(const byte*) main::SCREEN = (byte*) 1024
(const byte*) msg1[]  = (byte*) "hello world!"
(const byte*) msg2[]  = (byte*) "goodbye sky?"

zp[2]:2 [ first::return#2 first::return#0 first::return#1 main::$0 main::$2 ]


FINAL ASSEMBLER
Score: 66

  // File Comments
// Tests pointer plus 0 elimination
  // 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 __0 = 2
    .label __2 = 2
    // first(msg1)
    // [5] call first 
    // [14] phi from main to first [phi:main->first]
    // [14] phi (byte*) first::return#2 = (const byte*) msg1 [phi:main->first#0] -- pbuz1=pbuc1 
    lda #<msg1
    sta.z first.return
    lda #>msg1
    sta.z first.return+1
    jsr first
    // first(msg1)
    // [6] (byte*) first::return#0 ← (byte*) first::return#2
    // main::@1
    // [7] (byte*~) main::$0 ← (byte*) first::return#0
    // SCREEN[0] = *(first(msg1)+0)
    // [8] *((const byte*) main::SCREEN) ← *((byte*~) main::$0) -- _deref_pbuc1=_deref_pbuz1 
    ldy #0
    lda (__0),y
    sta SCREEN
    // first(msg2)
    // [9] call first 
    // [14] phi from main::@1 to first [phi:main::@1->first]
    // [14] phi (byte*) first::return#2 = (const byte*) msg2 [phi:main::@1->first#0] -- pbuz1=pbuc1 
    lda #<msg2
    sta.z first.return
    lda #>msg2
    sta.z first.return+1
    jsr first
    // first(msg2)
    // [10] (byte*) first::return#1 ← (byte*) first::return#2
    // main::@2
    // [11] (byte*~) main::$2 ← (byte*) first::return#1
    // SCREEN[1] = *(first(msg2)+0)
    // [12] *((const byte*) main::SCREEN+(byte) 1) ← *((byte*~) main::$2) -- _deref_pbuc1=_deref_pbuz1 
    ldy #0
    lda (__2),y
    sta SCREEN+1
    // main::@return
    // }
    // [13] return 
    rts
}
  // first
first: {
    .label return = 2
    // first::@return
    // [15] return 
    rts
}
  // File Data
  msg1: .text "hello world!"
  .byte 0
  msg2: .text "goodbye sky?"
  .byte 0

