Culled Empty Block (label) main::@2 CONTROL FLOW GRAPH SSA @begin: scope:[] from (byte[$f]) fibs ← { fill( $f, 0) } to:@1 (void()) main() main: scope:[main] from @1 *((byte[$f]) fibs + (number) 0) ← (number) 0 *((byte[$f]) fibs + (number) 1) ← (number) 1 (byte) main::i#0 ← (number) 0 to:main::@1 main::@1: scope:[main] from main main::@1 (byte) main::i#2 ← phi( main/(byte) main::i#0 main::@1/(byte) main::i#1 ) (number~) main::$0 ← (byte) main::i#2 + (number) 2 (number~) main::$1 ← (byte) main::i#2 + (number) 1 (byte~) main::$2 ← *((byte[$f]) fibs + (byte) main::i#2) + *((byte[$f]) fibs + (number~) main::$1) *((byte[$f]) fibs + (number~) main::$0) ← (byte~) main::$2 (byte) main::i#1 ← ++ (byte) main::i#2 (bool~) main::$3 ← (byte) main::i#1 < (number) $f if((bool~) main::$3) goto main::@1 to:main::@return main::@return: scope:[main] from main::@1 return to:@return @1: scope:[] from @begin call main to:@2 @2: scope:[] from @1 to:@end @end: scope:[] from @2 SYMBOL TABLE SSA (label) @1 (label) @2 (label) @begin (label) @end (byte[$f]) fibs (void()) main() (number~) main::$0 (number~) main::$1 (byte~) main::$2 (bool~) main::$3 (label) main::@1 (label) main::@return (byte) main::i (byte) main::i#0 (byte) main::i#1 (byte) main::i#2 Adding number conversion cast (unumber) 0 in *((byte[$f]) fibs + (number) 0) ← (number) 0 Adding number conversion cast (unumber) 0 in *((byte[$f]) fibs + (number) 0) ← ((unumber)) (number) 0 Adding number conversion cast (unumber) 1 in *((byte[$f]) fibs + (number) 1) ← (number) 1 Adding number conversion cast (unumber) 1 in *((byte[$f]) fibs + (number) 1) ← ((unumber)) (number) 1 Adding number conversion cast (unumber) 0 in (byte) main::i#0 ← (number) 0 Adding number conversion cast (unumber) 2 in (number~) main::$0 ← (byte) main::i#2 + (number) 2 Adding number conversion cast (unumber) main::$0 in (number~) main::$0 ← (byte) main::i#2 + (unumber)(number) 2 Adding number conversion cast (unumber) 1 in (number~) main::$1 ← (byte) main::i#2 + (number) 1 Adding number conversion cast (unumber) main::$1 in (number~) main::$1 ← (byte) main::i#2 + (unumber)(number) 1 Adding number conversion cast (unumber) $f in (bool~) main::$3 ← (byte) main::i#1 < (number) $f Successful SSA optimization PassNAddNumberTypeConversions Inlining cast *((byte[$f]) fibs + (unumber)(number) 0) ← (unumber)(number) 0 Inlining cast *((byte[$f]) fibs + (unumber)(number) 1) ← (unumber)(number) 1 Inlining cast (byte) main::i#0 ← (unumber)(number) 0 Successful SSA optimization Pass2InlineCast Simplifying constant integer cast 0 Simplifying constant integer cast 0 Simplifying constant integer cast 1 Simplifying constant integer cast 1 Simplifying constant integer cast 0 Simplifying constant integer cast 2 Simplifying constant integer cast 1 Simplifying constant integer cast $f Successful SSA optimization PassNCastSimplification Finalized unsigned number type (byte) 0 Finalized unsigned number type (byte) 0 Finalized unsigned number type (byte) 1 Finalized unsigned number type (byte) 1 Finalized unsigned number type (byte) 0 Finalized unsigned number type (byte) 2 Finalized unsigned number type (byte) 1 Finalized unsigned number type (byte) $f Successful SSA optimization PassNFinalizeNumberTypeConversions Inferred type updated to byte in (unumber~) main::$0 ← (byte) main::i#2 + (byte) 2 Inferred type updated to byte in (unumber~) main::$1 ← (byte) main::i#2 + (byte) 1 Simple Condition (bool~) main::$3 [11] if((byte) main::i#1<(byte) $f) goto main::@1 Successful SSA optimization Pass2ConditionalJumpSimplification Constant right-side identified [0] (byte[$f]) fibs ← { fill( $f, 0) } Successful SSA optimization Pass2ConstantRValueConsolidation Constant (const byte[$f]) fibs = { fill( $f, 0) } Constant (const byte) main::i#0 = 0 Successful SSA optimization Pass2ConstantIdentification Simplifying expression containing zero fibs in [1] *((const byte[$f]) fibs + (byte) 0) ← (byte) 0 Successful SSA optimization PassNSimplifyExpressionWithZero Inlining constant with var siblings (const byte) main::i#0 Constant inlined main::i#0 = (byte) 0 Successful SSA optimization Pass2ConstantInlining Consolidated array index constant in *(fibs+1) Consolidated array index constant in assignment *(fibs+1 + main::$1) Consolidated array index constant in assignment *(fibs+2 + main::$0) Successful SSA optimization Pass2ConstantAdditionElimination Alias (byte) main::i#2 = (byte~) main::$0 (byte~) main::$1 Successful SSA optimization Pass2AliasElimination Added new block during phi lifting main::@3(between main::@1 and main::@1) Adding NOP phi() at start of @begin Adding NOP phi() at start of @1 Adding NOP phi() at start of @2 Adding NOP phi() at start of @end CALL GRAPH Calls in [] to main:2 Created 1 initial phi equivalence classes Coalesced [13] main::i#3 ← main::i#1 Coalesced down to 1 phi equivalence classes Culled Empty Block (label) @2 Culled Empty Block (label) main::@3 Adding NOP phi() at start of @begin Adding NOP phi() at start of @1 Adding NOP phi() at start of @end FINAL CONTROL FLOW GRAPH @begin: scope:[] from [0] phi() to:@1 @1: scope:[] from @begin [1] phi() [2] call main to:@end @end: scope:[] from @1 [3] phi() (void()) main() main: scope:[main] from @1 [4] *((const byte[$f]) fibs) ← (byte) 0 [5] *((const byte[$f]) fibs+(byte) 1) ← (byte) 1 to:main::@1 main::@1: scope:[main] from main main::@1 [6] (byte) main::i#2 ← phi( main/(byte) 0 main::@1/(byte) main::i#1 ) [7] (byte~) main::$2 ← *((const byte[$f]) fibs + (byte) main::i#2) + *((const byte[$f]) fibs+(byte) 1 + (byte) main::i#2) [8] *((const byte[$f]) fibs+(byte) 2 + (byte) main::i#2) ← (byte~) main::$2 [9] (byte) main::i#1 ← ++ (byte) main::i#2 [10] if((byte) main::i#1<(byte) $f) goto main::@1 to:main::@return main::@return: scope:[main] from main::@1 [11] return to:@return VARIABLE REGISTER WEIGHTS (void()) main() (byte~) main::$2 22.0 (byte) main::i (byte) main::i#1 16.5 (byte) main::i#2 18.333333333333332 Initial phi equivalence classes [ main::i#2 main::i#1 ] Added variable main::$2 to zero page equivalence class [ main::$2 ] Complete equivalence classes [ main::i#2 main::i#1 ] [ main::$2 ] Allocated zp ZP_BYTE:2 [ main::i#2 main::i#1 ] Allocated zp ZP_BYTE:3 [ main::$2 ] INITIAL ASM Target platform is c64basic / MOS6502X // File Comments // Upstart .pc = $801 "Basic" :BasicUpstart(__bbegin) .pc = $80d "Program" // Global Constants & labels // @begin __bbegin: // [1] phi from @begin to @1 [phi:@begin->@1] __b1_from___bbegin: jmp __b1 // @1 __b1: // [2] call main jsr main // [3] phi from @1 to @end [phi:@1->@end] __bend_from___b1: jmp __bend // @end __bend: // main main: { .label __2 = 3 .label i = 2 // [4] *((const byte[$f]) fibs) ← (byte) 0 -- _deref_pbuc1=vbuc2 lda #0 sta fibs // [5] *((const byte[$f]) fibs+(byte) 1) ← (byte) 1 -- _deref_pbuc1=vbuc2 lda #1 sta fibs+1 // [6] phi from main to main::@1 [phi:main->main::@1] __b1_from_main: // [6] phi (byte) main::i#2 = (byte) 0 [phi:main->main::@1#0] -- vbuz1=vbuc1 lda #0 sta.z i jmp __b1 // [6] phi from main::@1 to main::@1 [phi:main::@1->main::@1] __b1_from___b1: // [6] phi (byte) main::i#2 = (byte) main::i#1 [phi:main::@1->main::@1#0] -- register_copy jmp __b1 // main::@1 __b1: // [7] (byte~) main::$2 ← *((const byte[$f]) fibs + (byte) main::i#2) + *((const byte[$f]) fibs+(byte) 1 + (byte) main::i#2) -- vbuz1=pbuc1_derefidx_vbuz2_plus_pbuc2_derefidx_vbuz2 ldy.z i lda fibs,y clc adc fibs+1,y sta.z __2 // [8] *((const byte[$f]) fibs+(byte) 2 + (byte) main::i#2) ← (byte~) main::$2 -- pbuc1_derefidx_vbuz1=vbuz2 lda.z __2 ldy.z i sta fibs+2,y // [9] (byte) main::i#1 ← ++ (byte) main::i#2 -- vbuz1=_inc_vbuz1 inc.z i // [10] if((byte) main::i#1<(byte) $f) goto main::@1 -- vbuz1_lt_vbuc1_then_la1 lda.z i cmp #$f bcc __b1_from___b1 jmp __breturn // main::@return __breturn: // [11] return rts } // File Data fibs: .fill $f, 0 REGISTER UPLIFT POTENTIAL REGISTERS Statement [4] *((const byte[$f]) fibs) ← (byte) 0 [ ] ( main:2 [ ] ) always clobbers reg byte a Statement [5] *((const byte[$f]) fibs+(byte) 1) ← (byte) 1 [ ] ( main:2 [ ] ) always clobbers reg byte a Statement [7] (byte~) main::$2 ← *((const byte[$f]) fibs + (byte) main::i#2) + *((const byte[$f]) fibs+(byte) 1 + (byte) main::i#2) [ main::i#2 main::$2 ] ( main:2 [ main::i#2 main::$2 ] ) always clobbers reg byte a Removing always clobbered register reg byte a as potential for zp ZP_BYTE:2 [ main::i#2 main::i#1 ] Statement [4] *((const byte[$f]) fibs) ← (byte) 0 [ ] ( main:2 [ ] ) always clobbers reg byte a Statement [5] *((const byte[$f]) fibs+(byte) 1) ← (byte) 1 [ ] ( main:2 [ ] ) always clobbers reg byte a Statement [7] (byte~) main::$2 ← *((const byte[$f]) fibs + (byte) main::i#2) + *((const byte[$f]) fibs+(byte) 1 + (byte) main::i#2) [ main::i#2 main::$2 ] ( main:2 [ main::i#2 main::$2 ] ) always clobbers reg byte a Potential registers zp ZP_BYTE:2 [ main::i#2 main::i#1 ] : zp ZP_BYTE:2 , reg byte x , reg byte y , Potential registers zp ZP_BYTE:3 [ main::$2 ] : zp ZP_BYTE:3 , reg byte a , reg byte x , reg byte y , REGISTER UPLIFT SCOPES Uplift Scope [main] 34.83: zp ZP_BYTE:2 [ main::i#2 main::i#1 ] 22: zp ZP_BYTE:3 [ main::$2 ] Uplift Scope [] Uplifting [main] best 365 combination reg byte x [ main::i#2 main::i#1 ] reg byte a [ main::$2 ] Uplifting [] best 365 combination ASSEMBLER BEFORE OPTIMIZATION // File Comments // Upstart .pc = $801 "Basic" :BasicUpstart(__bbegin) .pc = $80d "Program" // Global Constants & labels // @begin __bbegin: // [1] phi from @begin to @1 [phi:@begin->@1] __b1_from___bbegin: jmp __b1 // @1 __b1: // [2] call main jsr main // [3] phi from @1 to @end [phi:@1->@end] __bend_from___b1: jmp __bend // @end __bend: // main main: { // [4] *((const byte[$f]) fibs) ← (byte) 0 -- _deref_pbuc1=vbuc2 lda #0 sta fibs // [5] *((const byte[$f]) fibs+(byte) 1) ← (byte) 1 -- _deref_pbuc1=vbuc2 lda #1 sta fibs+1 // [6] phi from main to main::@1 [phi:main->main::@1] __b1_from_main: // [6] phi (byte) main::i#2 = (byte) 0 [phi:main->main::@1#0] -- vbuxx=vbuc1 ldx #0 jmp __b1 // [6] phi from main::@1 to main::@1 [phi:main::@1->main::@1] __b1_from___b1: // [6] phi (byte) main::i#2 = (byte) main::i#1 [phi:main::@1->main::@1#0] -- register_copy jmp __b1 // main::@1 __b1: // [7] (byte~) main::$2 ← *((const byte[$f]) fibs + (byte) main::i#2) + *((const byte[$f]) fibs+(byte) 1 + (byte) main::i#2) -- vbuaa=pbuc1_derefidx_vbuxx_plus_pbuc2_derefidx_vbuxx lda fibs,x clc adc fibs+1,x // [8] *((const byte[$f]) fibs+(byte) 2 + (byte) main::i#2) ← (byte~) main::$2 -- pbuc1_derefidx_vbuxx=vbuaa sta fibs+2,x // [9] (byte) main::i#1 ← ++ (byte) main::i#2 -- vbuxx=_inc_vbuxx inx // [10] if((byte) main::i#1<(byte) $f) goto main::@1 -- vbuxx_lt_vbuc1_then_la1 cpx #$f bcc __b1_from___b1 jmp __breturn // main::@return __breturn: // [11] return rts } // File Data fibs: .fill $f, 0 ASSEMBLER OPTIMIZATIONS Removing instruction jmp __b1 Removing instruction jmp __bend Removing instruction jmp __b1 Removing instruction jmp __breturn Succesful ASM optimization Pass5NextJumpElimination Replacing label __bbegin with __b1 Replacing label __b1_from___b1 with __b1 Removing instruction __bbegin: Removing instruction __b1_from___bbegin: Removing instruction __bend_from___b1: Removing instruction __b1_from___b1: Succesful ASM optimization Pass5RedundantLabelElimination Removing instruction __bend: Removing instruction __b1_from_main: Removing instruction __breturn: Succesful ASM optimization Pass5UnusedLabelElimination Updating BasicUpstart to call main directly Removing instruction jsr main Succesful ASM optimization Pass5SkipBegin Removing instruction jmp __b1 Succesful ASM optimization Pass5NextJumpElimination Removing instruction __b1: Succesful ASM optimization Pass5UnusedLabelElimination FINAL SYMBOL TABLE (label) @1 (label) @begin (label) @end (const byte[$f]) fibs fibs = { fill( $f, 0) } (void()) main() (byte~) main::$2 reg byte a 22.0 (label) main::@1 (label) main::@return (byte) main::i (byte) main::i#1 reg byte x 16.5 (byte) main::i#2 reg byte x 18.333333333333332 reg byte x [ main::i#2 main::i#1 ] reg byte a [ main::$2 ] FINAL ASSEMBLER Score: 263 // File Comments // Upstart .pc = $801 "Basic" :BasicUpstart(main) .pc = $80d "Program" // Global Constants & labels // @begin // [1] phi from @begin to @1 [phi:@begin->@1] // @1 // [2] call main // [3] phi from @1 to @end [phi:@1->@end] // @end // main main: { // fibs[0] = 0 // [4] *((const byte[$f]) fibs) ← (byte) 0 -- _deref_pbuc1=vbuc2 lda #0 sta fibs // fibs[1] = 1 // [5] *((const byte[$f]) fibs+(byte) 1) ← (byte) 1 -- _deref_pbuc1=vbuc2 lda #1 sta fibs+1 // [6] phi from main to main::@1 [phi:main->main::@1] // [6] phi (byte) main::i#2 = (byte) 0 [phi:main->main::@1#0] -- vbuxx=vbuc1 ldx #0 // [6] phi from main::@1 to main::@1 [phi:main::@1->main::@1] // [6] phi (byte) main::i#2 = (byte) main::i#1 [phi:main::@1->main::@1#0] -- register_copy // main::@1 __b1: // fibs[i]+fibs[i+1] // [7] (byte~) main::$2 ← *((const byte[$f]) fibs + (byte) main::i#2) + *((const byte[$f]) fibs+(byte) 1 + (byte) main::i#2) -- vbuaa=pbuc1_derefidx_vbuxx_plus_pbuc2_derefidx_vbuxx lda fibs,x clc adc fibs+1,x // fibs[i+2] = fibs[i]+fibs[i+1] // [8] *((const byte[$f]) fibs+(byte) 2 + (byte) main::i#2) ← (byte~) main::$2 -- pbuc1_derefidx_vbuxx=vbuaa sta fibs+2,x // while(++i<15) // [9] (byte) main::i#1 ← ++ (byte) main::i#2 -- vbuxx=_inc_vbuxx inx // [10] if((byte) main::i#1<(byte) $f) goto main::@1 -- vbuxx_lt_vbuc1_then_la1 cpx #$f bcc __b1 // main::@return // } // [11] return rts } // File Data fibs: .fill $f, 0