Resolved forward reference irq to interrupt(KERNEL_MIN)(void()) irq()

CONTROL FLOW GRAPH SSA
@begin: scope:[]  from
  (volatile byte) col ← (byte) 0
  to:@1

(void()) main()
main: scope:[main]  from @1
  *((const nomodify void()**) KERNEL_IRQ) ← &interrupt(KERNEL_MIN)(void()) irq()
  to:main::@1
main::@1: scope:[main]  from main main::@2 main::@3
  if(true) goto main::@2
  to:main::@return
main::@2: scope:[main]  from main::@1
  (bool~) main::$0 ← (volatile byte) col > (number) $a
  (bool~) main::$1 ← ! (bool~) main::$0
  if((bool~) main::$1) goto main::@1
  to:main::@3
main::@3: scope:[main]  from main::@2
  (volatile byte) col ← (number) 0
  to:main::@1
main::@return: scope:[main]  from main::@1
  return 
  to:@return

interrupt(KERNEL_MIN)(void()) irq()
irq: scope:[irq]  from
  asm { lda$dc0d  }
  *((const nomodify byte*) BG_COLOR) ← (volatile byte) col
  (bool~) irq::$0 ← (volatile byte) col != (number) 0
  if((bool~) irq::$0) goto irq::@1
  to:irq::@2
irq::@1: scope:[irq]  from irq
  (volatile byte) col ← ++ (volatile byte) col
  to:irq::@return
irq::@2: scope:[irq]  from irq
  (volatile byte) col ← (volatile byte) col + (number) 2
  to:irq::@return
irq::@return: scope:[irq]  from irq::@1 irq::@2
  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
(const nomodify byte*) BG_COLOR = (byte*)(number) $d020
(const nomodify void()**) KERNEL_IRQ = (void()**)(number) $314
(volatile byte) col loadstore
interrupt(KERNEL_MIN)(void()) irq()
(bool~) irq::$0
(label) irq::@1
(label) irq::@2
(label) irq::@return
(void()) main()
(bool~) main::$0
(bool~) main::$1
(label) main::@1
(label) main::@2
(label) main::@3
(label) main::@return

Adding number conversion cast (unumber) $a in (bool~) main::$0 ← (volatile byte) col > (number) $a
Adding number conversion cast (unumber) 0 in (volatile byte) col ← (number) 0
Adding number conversion cast (unumber) 0 in (bool~) irq::$0 ← (volatile byte) col != (number) 0
Adding number conversion cast (unumber) 2 in (volatile byte) col ← (volatile byte) col + (number) 2
Successful SSA optimization PassNAddNumberTypeConversions
Inlining cast (volatile byte) col ← (unumber)(number) 0
Successful SSA optimization Pass2InlineCast
Simplifying constant pointer cast (void()**) 788
Simplifying constant pointer cast (byte*) 53280
Simplifying constant integer cast $a
Simplifying constant integer cast 0
Simplifying constant integer cast 0
Simplifying constant integer cast 2
Successful SSA optimization PassNCastSimplification
Finalized unsigned number type (byte) $a
Finalized unsigned number type (byte) 0
Finalized unsigned number type (byte) 0
Finalized unsigned number type (byte) 2
Successful SSA optimization PassNFinalizeNumberTypeConversions
Inversing boolean not [4] (bool~) main::$1 ← (volatile byte) col <= (byte) $a from [3] (bool~) main::$0 ← (volatile byte) col > (byte) $a
Successful SSA optimization Pass2UnaryNotSimplification
Simple Condition (bool~) main::$1 [4] if((volatile byte) col<=(byte) $a) goto main::@1
Simple Condition (bool~) irq::$0 [10] if((volatile byte) col!=(byte) 0) goto irq::@1
Successful SSA optimization Pass2ConditionalJumpSimplification
if() condition always true - replacing block destination [2] if(true) goto main::@2
Successful SSA optimization Pass2ConstantIfs
Rewriting conditional comparison [4] if((volatile byte) col<=(byte) $a) goto main::@1
Removing unused block main::@return
Successful SSA optimization Pass2EliminateUnusedBlocks
Adding number conversion cast (unumber) $a+1 in if((volatile byte) col<(byte) $a+(number) 1) goto main::@1
Adding number conversion cast (unumber) 1 in if((volatile byte) col<(unumber)(byte) $a+(number) 1) goto main::@1
Successful SSA optimization PassNAddNumberTypeConversions
Simplifying constant integer cast (byte) $a+(unumber)(number) 1
Simplifying constant integer cast 1
Successful SSA optimization PassNCastSimplification
Finalized unsigned number type (byte) 1
Successful SSA optimization PassNFinalizeNumberTypeConversions
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::@1
CALL GRAPH
Calls in [] to main:2 

Created 0 initial phi equivalence classes
Coalesced down to 0 phi equivalence classes
Culled Empty Block (label) @2
Culled Empty Block (label) main::@1
Renumbering block main::@2 to main::@1
Renumbering block main::@3 to main::@2
Adding NOP phi() at start of @1
Adding NOP phi() at start of @end

FINAL CONTROL FLOW GRAPH
@begin: scope:[]  from
  [0] (volatile byte) col ← (byte) 0
  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] *((const nomodify void()**) KERNEL_IRQ) ← &interrupt(KERNEL_MIN)(void()) irq()
  to:main::@1
main::@1: scope:[main]  from main main::@1 main::@2
  [5] if((volatile byte) col<(byte) $a+(byte) 1) goto main::@1
  to:main::@2
main::@2: scope:[main]  from main::@1
  [6] (volatile byte) col ← (byte) 0
  to:main::@1

interrupt(KERNEL_MIN)(void()) irq()
irq: scope:[irq]  from
  asm { lda$dc0d  }
  [8] *((const nomodify byte*) BG_COLOR) ← (volatile byte) col
  [9] if((volatile byte) col!=(byte) 0) goto irq::@1
  to:irq::@2
irq::@2: scope:[irq]  from irq
  [10] (volatile byte) col ← (volatile byte) col + (byte) 2
  to:irq::@return
irq::@return: scope:[irq]  from irq::@1 irq::@2
  [11] return 
  to:@return
irq::@1: scope:[irq]  from irq
  [12] (volatile byte) col ← ++ (volatile byte) col
  to:irq::@return


VARIABLE REGISTER WEIGHTS
(volatile byte) col loadstore 139.5
interrupt(KERNEL_MIN)(void()) irq()
(void()) main()

Initial phi equivalence classes
Added variable col to live range equivalence class [ col ]
Complete equivalence classes
[ col ]
Allocated zp[1]:2 [ col ]

INITIAL ASM
Target platform is c64basic / MOS6502X
  // File Comments
// Tests that volatile variables can be both read & written inside & outside interrupts
// Currently fails because the modification is optimized away
  // Upstart
.pc = $801 "Basic"
:BasicUpstart(__bbegin)
.pc = $80d "Program"
  // Global Constants & labels
  .label KERNEL_IRQ = $314
  .label BG_COLOR = $d020
  .label col = 2
  // @begin
__bbegin:
  // [0] (volatile byte) col ← (byte) 0 -- vbuz1=vbuc1 
  lda #0
  sta.z col
  // [1] phi from @begin to @1 [phi:@begin->@1]
__b1_from___bbegin:
  jmp __b1
  // @1
__b1:
  // [2] call main 
  jsr main
  // [3] phi from @1 to @end [phi:@1->@end]
__bend_from___b1:
  jmp __bend
  // @end
__bend:
  // main
main: {
    // [4] *((const nomodify void()**) KERNEL_IRQ) ← &interrupt(KERNEL_MIN)(void()) irq() -- _deref_pptc1=pprc2 
    lda #<irq
    sta KERNEL_IRQ
    lda #>irq
    sta KERNEL_IRQ+1
    jmp __b1
    // main::@1
  __b1:
    // [5] if((volatile byte) col<(byte) $a+(byte) 1) goto main::@1 -- vbuz1_lt_vbuc1_then_la1 
    lda.z col
    cmp #$a+1
    bcc __b1
    jmp __b2
    // main::@2
  __b2:
    // [6] (volatile byte) col ← (byte) 0 -- vbuz1=vbuc1 
    lda #0
    sta.z col
    jmp __b1
}
  // irq
irq: {
    // entry interrupt(KERNEL_MIN)
    // asm { lda$dc0d  }
    lda $dc0d
    // [8] *((const nomodify byte*) BG_COLOR) ← (volatile byte) col -- _deref_pbuc1=vbuz1 
    lda.z col
    sta BG_COLOR
    // [9] if((volatile byte) col!=(byte) 0) goto irq::@1 -- vbuz1_neq_0_then_la1 
    lda.z col
    cmp #0
    bne __b1
    jmp __b2
    // irq::@2
  __b2:
    // [10] (volatile byte) col ← (volatile byte) col + (byte) 2 -- vbuz1=vbuz1_plus_2 
    lda.z col
    clc
    adc #2
    sta.z col
    jmp __breturn
    // irq::@return
  __breturn:
    // [11] return  - exit interrupt(KERNEL_MIN)
    jmp $ea81
    // irq::@1
  __b1:
    // [12] (volatile byte) col ← ++ (volatile byte) col -- vbuz1=_inc_vbuz1 
    inc.z col
    jmp __breturn
}
  // File Data

REGISTER UPLIFT POTENTIAL REGISTERS
Statement [0] (volatile byte) col ← (byte) 0 [ col ] (  [ col ] { }  ) always clobbers reg byte a 
Statement [4] *((const nomodify void()**) KERNEL_IRQ) ← &interrupt(KERNEL_MIN)(void()) irq() [ col ] ( main:2 [ col ] { }  ) always clobbers reg byte a 
Statement [5] if((volatile byte) col<(byte) $a+(byte) 1) goto main::@1 [ col ] ( main:2 [ col ] { }  ) always clobbers reg byte a 
Statement [6] (volatile byte) col ← (byte) 0 [ col ] ( main:2 [ col ] { }  ) always clobbers reg byte a 
Statement asm { lda$dc0d  } always clobbers reg byte a 
Statement [8] *((const nomodify byte*) BG_COLOR) ← (volatile byte) col [ col ] (  [ col ] { }  ) always clobbers reg byte a 
Statement [9] if((volatile byte) col!=(byte) 0) goto irq::@1 [ col ] (  [ col ] { }  ) always clobbers reg byte a 
Statement [10] (volatile byte) col ← (volatile byte) col + (byte) 2 [ ] (  [ ] { }  ) always clobbers reg byte a 
Potential registers zp[1]:2 [ col ] : zp[1]:2 , 

REGISTER UPLIFT SCOPES
Uplift Scope [] 139.5: zp[1]:2 [ col ] 
Uplift Scope [main] 
Uplift Scope [irq] 

Uplifting [] best 1207 combination zp[1]:2 [ col ] 
Uplifting [main] best 1207 combination 
Uplifting [irq] best 1207 combination 
Attempting to uplift remaining variables inzp[1]:2 [ col ]
Uplifting [] best 1207 combination zp[1]:2 [ col ] 

ASSEMBLER BEFORE OPTIMIZATION
  // File Comments
// Tests that volatile variables can be both read & written inside & outside interrupts
// Currently fails because the modification is optimized away
  // Upstart
.pc = $801 "Basic"
:BasicUpstart(__bbegin)
.pc = $80d "Program"
  // Global Constants & labels
  .label KERNEL_IRQ = $314
  .label BG_COLOR = $d020
  .label col = 2
  // @begin
__bbegin:
  // [0] (volatile byte) col ← (byte) 0 -- vbuz1=vbuc1 
  lda #0
  sta.z col
  // [1] phi from @begin to @1 [phi:@begin->@1]
__b1_from___bbegin:
  jmp __b1
  // @1
__b1:
  // [2] call main 
  jsr main
  // [3] phi from @1 to @end [phi:@1->@end]
__bend_from___b1:
  jmp __bend
  // @end
__bend:
  // main
main: {
    // [4] *((const nomodify void()**) KERNEL_IRQ) ← &interrupt(KERNEL_MIN)(void()) irq() -- _deref_pptc1=pprc2 
    lda #<irq
    sta KERNEL_IRQ
    lda #>irq
    sta KERNEL_IRQ+1
    jmp __b1
    // main::@1
  __b1:
    // [5] if((volatile byte) col<(byte) $a+(byte) 1) goto main::@1 -- vbuz1_lt_vbuc1_then_la1 
    lda.z col
    cmp #$a+1
    bcc __b1
    jmp __b2
    // main::@2
  __b2:
    // [6] (volatile byte) col ← (byte) 0 -- vbuz1=vbuc1 
    lda #0
    sta.z col
    jmp __b1
}
  // irq
irq: {
    // entry interrupt(KERNEL_MIN)
    // asm { lda$dc0d  }
    lda $dc0d
    // [8] *((const nomodify byte*) BG_COLOR) ← (volatile byte) col -- _deref_pbuc1=vbuz1 
    lda.z col
    sta BG_COLOR
    // [9] if((volatile byte) col!=(byte) 0) goto irq::@1 -- vbuz1_neq_0_then_la1 
    lda.z col
    cmp #0
    bne __b1
    jmp __b2
    // irq::@2
  __b2:
    // [10] (volatile byte) col ← (volatile byte) col + (byte) 2 -- vbuz1=vbuz1_plus_2 
    lda.z col
    clc
    adc #2
    sta.z col
    jmp __breturn
    // irq::@return
  __breturn:
    // [11] return  - exit interrupt(KERNEL_MIN)
    jmp $ea81
    // irq::@1
  __b1:
    // [12] (volatile byte) col ← ++ (volatile byte) col -- vbuz1=_inc_vbuz1 
    inc.z col
    jmp __breturn
}
  // File Data

ASSEMBLER OPTIMIZATIONS
Removing instruction jmp __b1
Removing instruction jmp __bend
Removing instruction jmp __b1
Removing instruction jmp __b2
Removing instruction jmp __b2
Removing instruction jmp __breturn
Succesful ASM optimization Pass5NextJumpElimination
Removing instruction __b1_from___bbegin:
Removing instruction __bend_from___b1:
Succesful ASM optimization Pass5RedundantLabelElimination
Removing instruction __b1:
Removing instruction __bend:
Removing instruction __b2:
Removing instruction __b2:
Succesful ASM optimization Pass5UnusedLabelElimination
Skipping double jump to $ea81 in jmp __breturn
Succesful ASM optimization Pass5DoubleJumpElimination
Adding RTS to root block 
Succesful ASM optimization Pass5AddMainRts
Removing instruction lda.z col
Succesful ASM optimization Pass5UnnecesaryLoadElimination
Removing instruction __breturn:
Succesful ASM optimization Pass5UnusedLabelElimination

FINAL SYMBOL TABLE
(label) @1
(label) @begin
(label) @end
(const nomodify byte*) BG_COLOR = (byte*) 53280
(const nomodify void()**) KERNEL_IRQ = (void()**) 788
(volatile byte) col loadstore zp[1]:2 139.5
interrupt(KERNEL_MIN)(void()) irq()
(label) irq::@1
(label) irq::@2
(label) irq::@return
(void()) main()
(label) main::@1
(label) main::@2

zp[1]:2 [ col ]


FINAL ASSEMBLER
Score: 895

  // File Comments
// Tests that volatile variables can be both read & written inside & outside interrupts
// Currently fails because the modification is optimized away
  // Upstart
.pc = $801 "Basic"
:BasicUpstart(__bbegin)
.pc = $80d "Program"
  // Global Constants & labels
  .label KERNEL_IRQ = $314
  .label BG_COLOR = $d020
  .label col = 2
  // @begin
__bbegin:
  // col = 0
  // [0] (volatile byte) col ← (byte) 0 -- vbuz1=vbuc1 
  lda #0
  sta.z col
  // [1] phi from @begin to @1 [phi:@begin->@1]
  // @1
  // [2] call main 
  jsr main
  rts
  // [3] phi from @1 to @end [phi:@1->@end]
  // @end
  // main
main: {
    // *KERNEL_IRQ = &irq
    // [4] *((const nomodify void()**) KERNEL_IRQ) ← &interrupt(KERNEL_MIN)(void()) irq() -- _deref_pptc1=pprc2 
    lda #<irq
    sta KERNEL_IRQ
    lda #>irq
    sta KERNEL_IRQ+1
    // main::@1
  __b1:
    // if(col>10)
    // [5] if((volatile byte) col<(byte) $a+(byte) 1) goto main::@1 -- vbuz1_lt_vbuc1_then_la1 
    lda.z col
    cmp #$a+1
    bcc __b1
    // main::@2
    // col = 0
    // [6] (volatile byte) col ← (byte) 0 -- vbuz1=vbuc1 
    lda #0
    sta.z col
    jmp __b1
}
  // irq
irq: {
    // entry interrupt(KERNEL_MIN)
    // asm
    // asm { lda$dc0d  }
    lda $dc0d
    // *BG_COLOR = col
    // [8] *((const nomodify byte*) BG_COLOR) ← (volatile byte) col -- _deref_pbuc1=vbuz1 
    lda.z col
    sta BG_COLOR
    // if(col!=0)
    // [9] if((volatile byte) col!=(byte) 0) goto irq::@1 -- vbuz1_neq_0_then_la1 
    lda.z col
    cmp #0
    bne __b1
    // irq::@2
    // col += 2
    // [10] (volatile byte) col ← (volatile byte) col + (byte) 2 -- vbuz1=vbuz1_plus_2 
    clc
    adc #2
    sta.z col
    // irq::@return
    // }
    // [11] return  - exit interrupt(KERNEL_MIN)
    jmp $ea81
    // irq::@1
  __b1:
    // col++;
    // [12] (volatile byte) col ← ++ (volatile byte) col -- vbuz1=_inc_vbuz1 
    inc.z col
    jmp $ea81
}
  // File Data