main

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sources

 
 
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/Users/mohammed/projects/gopheradvent.com/site/content/calendar/2021/lisp-in-go/main.go
func main() {
	var int_16 int16 = 0
	int_16 = 6
	var float_64_1 float64 = 1
	var float_64_a float64 = float64(int_16)
	var float_64_b = float_64_a + float_64_1
	print(float_64_b)
}

AST

buildssa-enter
buildssa-body
. DCL tc(1) # main.go:4
. . NAME-main.int_16 esc(no) tc(1) Class:PAUTO Offset:0 OnStack Used int16 # main.go:4
. AS tc(1) # main.go:4
. . NAME-main.int_16 esc(no) tc(1) Class:PAUTO Offset:0 OnStack Used int16 # main.go:4
. . LITERAL-0 tc(1) int16 # main.go:4
. AS tc(1) # main.go:5
. . NAME-main.int_16 esc(no) tc(1) Class:PAUTO Offset:0 OnStack Used int16 # main.go:4
. . LITERAL-6 tc(1) int16 # main.go:5
. DCL tc(1) # main.go:6
. . NAME-main.float_64_1 esc(no) tc(1) Class:PAUTO Offset:0 OnStack Used float64 # main.go:6
. AS tc(1) # main.go:6
. . NAME-main.float_64_1 esc(no) tc(1) Class:PAUTO Offset:0 OnStack Used float64 # main.go:6
. . LITERAL-1 tc(1) float64 # main.go:6
. DCL tc(1) # main.go:7
. . NAME-main.float_64_a esc(no) tc(1) Class:PAUTO Offset:0 OnStack Used float64 # main.go:7
. AS tc(1) # main.go:7
. . NAME-main.float_64_a esc(no) tc(1) Class:PAUTO Offset:0 OnStack Used float64 # main.go:7
. . CONV tc(1) float64 # main.go:7 float64
. . . NAME-main.int_16 esc(no) tc(1) Class:PAUTO Offset:0 OnStack Used int16 # main.go:4
. DCL tc(1) # main.go:8
. . NAME-main.float_64_b esc(no) tc(1) Class:PAUTO Offset:0 OnStack Used float64 # main.go:8
. AS tc(1) # main.go:8
. . NAME-main.float_64_b esc(no) tc(1) Class:PAUTO Offset:0 OnStack Used float64 # main.go:8
. . ADD tc(1) float64 # main.go:8 float64
. . . NAME-main.float_64_a esc(no) tc(1) Class:PAUTO Offset:0 OnStack Used float64 # main.go:7
. . . NAME-main.float_64_1 esc(no) tc(1) Class:PAUTO Offset:0 OnStack Used float64 # main.go:6
. BLOCK tc(1) # main.go:9
. BLOCK-List
. . CALLFUNC tc(1) Use:3 Walked # main.go:9
. . . NAME-runtime.printlock tc(1) Class:PFUNC Offset:0 Used FUNC-func()
. . CALLFUNC tc(1) Use:3 Walked # main.go:9
. . . NAME-runtime.printfloat tc(1) Class:PFUNC Offset:0 Used FUNC-func(float64)
. . CALLFUNC-Args
. . . NAME-main.float_64_b esc(no) tc(1) Class:PAUTO Offset:0 OnStack Used float64 # main.go:8
. . CALLFUNC tc(1) Use:3 Walked # main.go:9
. . . NAME-runtime.printunlock tc(1) Class:PFUNC Offset:0 Used FUNC-func()
buildssa-exit
 

before insert phis

  • b1:
    • v1 (?) = InitMem <mem>
    • v2 (?) = SP <uintptr>
    • v3 (?) = SB <uintptr>
    • v4 (?) = GetClosurePtr <*uint8>
    • v5 (?) = Const16 <int16> [0] (int_16[int16])
    • v6 (?) = Const16 <int16> [6] (int_16[int16])
    • v7 (?) = Const64F <float64> [1] (float_64_1[float64])
    • v8 (7) = SignExt16to32 <int32> v6
    • v9 (7) = Cvt32to64F <float64> v8 (float_64_a[float64])
    • v10 (8) = Add64F <float64> v9 v7 (float_64_b[float64])
    • v11 (9) = StaticLECall <mem> {AuxCall{runtime.printlock}} v1
    • v12 (9) = SelectN <mem> [0] v11
    • v13 (9) = StaticLECall <mem> {AuxCall{runtime.printfloat}} [8] v10 v12
    • v14 (9) = SelectN <mem> [0] v13
    • v15 (9) = StaticLECall <mem> {AuxCall{runtime.printunlock}} v14
    • v16 (9) = SelectN <mem> [0] v15
    • v17 (10) = MakeResult <mem> v16
  • Ret v17 (10)
  • name int_16[int16]: v5 v6
  • name float_64_1[float64]: v7
  • name float_64_a[float64]: v9
  • name float_64_b[float64]: v10

    • start

    number lines [557340 ns]

    early phielim [3594 ns]

    early copyelim [969 ns]

    early deadcode [9215 ns]

    • b1:
      • v1 (?) = InitMem <mem>
      • v6 (?) = Const16 <int16> [6] (int_16[int16])
      • v7 (?) = Const64F <float64> [1] (float_64_1[float64])
      • v8 (+7) = SignExt16to32 <int32> v6
      • v9 (7) = Cvt32to64F <float64> v8 (float_64_a[float64])
      • v10 (+8) = Add64F <float64> v9 v7 (float_64_b[float64])
      • v11 (+9) = StaticLECall <mem> {AuxCall{runtime.printlock}} v1
      • v12 (9) = SelectN <mem> [0] v11
      • v13 (9) = StaticLECall <mem> {AuxCall{runtime.printfloat}} [8] v10 v12
      • v14 (9) = SelectN <mem> [0] v13
      • v15 (9) = StaticLECall <mem> {AuxCall{runtime.printunlock}} v14
      • v16 (9) = SelectN <mem> [0] v15
      • v17 (+10) = MakeResult <mem> v16
    • Ret v17 (10)
  • name int_16[int16]: v6
  • name float_64_1[float64]: v7
  • name float_64_a[float64]: v9
  • name float_64_b[float64]: v10

    • short circuit [7692 ns]

    decompose user [2896 ns]

    pre-opt deadcode [3309 ns]

    opt [2439862 ns]

    • b1:
      • v1 (?) = InitMem <mem>
      • v10 (+8) = Const64F <float64> [7] (float_64_b[float64])
      • v11 (+9) = StaticLECall <mem> {AuxCall{runtime.printlock}} v1
      • v12 (9) = SelectN <mem> [0] v11
      • v13 (9) = StaticLECall <mem> {AuxCall{runtime.printfloat}} [8] v10 v12
      • v14 (9) = SelectN <mem> [0] v13
      • v15 (9) = StaticLECall <mem> {AuxCall{runtime.printunlock}} v14
      • v16 (9) = SelectN <mem> [0] v15
      • v17 (+10) = MakeResult <mem> v16
    • Ret v17 (10)
  • name int_16[int16]: v6
  • name float_64_1[float64]: v7
  • name float_64_a[float64]: v9
  • name float_64_b[float64]: v10

    • zero arg cse [2733 ns]

    opt deadcode [4810 ns]

    • b1:
      • v1 (?) = InitMem <mem>
      • v10 (+8) = Const64F <float64> [7] (float_64_b[float64])
      • v11 (+9) = StaticLECall <mem> {AuxCall{runtime.printlock}} v1
      • v12 (9) = SelectN <mem> [0] v11
      • v13 (9) = StaticLECall <mem> {AuxCall{runtime.printfloat}} [8] v10 v12
      • v14 (9) = SelectN <mem> [0] v13
      • v15 (9) = StaticLECall <mem> {AuxCall{runtime.printunlock}} v14
      • v16 (9) = SelectN <mem> [0] v15
      • v17 (+10) = MakeResult <mem> v16
    • Ret v17 (10)
  • name float_64_b[float64]: v10

    • generic cse [38622 ns]

    phiopt [2911 ns]

    gcse deadcode [3302 ns]

    nilcheckelim [10143 ns]

    prove [14267 ns]

    • b1:
      • v1 (?) = InitMem <mem>
      • v10 (+8) = Const64F <float64> [7] (float_64_b[float64])
      • v11 (+9) = StaticLECall <mem> {AuxCall{runtime.printlock}} v1
      • v12 (9) = SelectN <mem> [0] v11
      • v13 (9) = StaticLECall <mem> {AuxCall{runtime.printfloat}} [8] v10 v12
      • v14 (9) = SelectN <mem> [0] v13
      • v15 (9) = StaticLECall <mem> {AuxCall{runtime.printunlock}} v14
      • v16 (9) = SelectN <mem> [0] v15
      • v17 (+10) = MakeResult <mem> v16
      • v9 (?) = Const64 <int64> [0]
    • Ret v17 (10)
  • name float_64_b[float64]: v10

    • early fuse [3389 ns]

    decompose builtin [531350 ns]

    expand calls [270026 ns]

    • b1:
      • v1 (?) = InitMem <mem>
      • v10 (+8) = Const64F <float64> [7] (float_64_b[float64])
      • v11 (+9) = StaticCall <mem> {AuxCall{runtime.printlock}} v1
      • v12 (9) = SelectN <mem> [0] v11
      • v13 (9) = StaticCall <mem> {AuxCall{runtime.printfloat}} [8] v10 v12
      • v14 (9) = SelectN <mem> [0] v13
      • v15 (9) = StaticCall <mem> {AuxCall{runtime.printunlock}} v14
      • v16 (9) = SelectN <mem> [0] v15
      • v17 (+10) = MakeResult <mem> v16
      • v9 (?) = Const64 <int64> [0]
      • v8 (?) = SB <uintptr>
      • v7 (?) = SP <uintptr>
    • Ret v17 (10)
  • name float_64_b[float64]: v10

    • softfloat [349 ns]

    late opt [4654 ns]

    • b1:
      • v1 (?) = InitMem <mem>
      • v10 (+8) = Const64F <float64> [7] (float_64_b[float64])
      • v11 (+9) = StaticCall <mem> {AuxCall{runtime.printlock}} v1
      • v12 (9) = SelectN <mem> [0] v11
      • v13 (9) = StaticCall <mem> {AuxCall{runtime.printfloat}} [8] v10 v12
      • v14 (9) = SelectN <mem> [0] v13
      • v15 (9) = StaticCall <mem> {AuxCall{runtime.printunlock}} v14
      • v16 (9) = SelectN <mem> [0] v15
      • v17 (+10) = MakeResult <mem> v16
    • Ret v17 (10)
  • name float_64_b[float64]: v10

    • dead auto elim [517189 ns]

    generic deadcode [6149 ns]

    check bce [209 ns]

    branchelim [5270 ns]

    late fuse [3508 ns]

    • b1:
      • v1 (?) = InitMem <mem>
      • v10 (+8) = Const64F <float64> [7] (float_64_b[float64])
      • v11 (+9) = StaticCall <mem> {AuxCall{runtime.printlock}} v1
      • v12 (9) = SelectN <mem> [0] v11
      • v13 (9) = StaticCall <mem> {AuxCall{runtime.printfloat}} [8] v10 v12
      • v14 (9) = SelectN <mem> [0] v13
      • v15 (9) = StaticCall <mem> {AuxCall{runtime.printunlock}} v14
      • v16 (9) = SelectN <mem> [0] v15
      • v17 (+10) = MakeResult <mem> v16
      • v7 (?) = Const64 <int64> [0]
    • Ret v17 (10)
  • name float_64_b[float64]: v10

    • dse [10429 ns]

    writebarrier [5496 ns]

    lower [895081 ns]

    • b1:
      • v1 (?) = InitMem <mem>
      • v10 (+8) = MOVSDconst <float64> [7] (float_64_b[float64])
      • v11 (+9) = CALLstatic <mem> {AuxCall{runtime.printlock}} v1
      • v12 (9) = SelectN <mem> [0] v11
      • v13 (9) = CALLstatic <mem> {AuxCall{runtime.printfloat}} [8] v10 v12
      • v14 (9) = SelectN <mem> [0] v13
      • v15 (9) = CALLstatic <mem> {AuxCall{runtime.printunlock}} v14
      • v16 (9) = SelectN <mem> [0] v15
      • v17 (+10) = MakeResult <mem> v16
    • Ret v17 (10)
  • name float_64_b[float64]: v10

    • addressing modes [1315 ns]

    lowered deadcode for cse [3729 ns]

    lowered cse [3138 ns]

    elim unread autos [374 ns]

    tighten tuple selectors [1344 ns]

    lowered deadcode [1303 ns]

    checkLower [350 ns]

    late phielim [378 ns]

    late copyelim [237 ns]

    tighten [14007 ns]

    late deadcode [1191 ns]

    critical [296 ns]

    phi tighten [166 ns]

    likelyadjust [310 ns]

    layout [841 ns]

    schedule [7955 ns]

    • b1:
      • v1 (?) = InitMem <mem>
      • v11 (+9) = CALLstatic <mem> {AuxCall{runtime.printlock}} v1
      • v12 (9) = SelectN <mem> [0] v11
      • v10 (+8) = MOVSDconst <float64> [7] (float_64_b[float64])
      • v13 (9) = CALLstatic <mem> {AuxCall{runtime.printfloat}} [8] v10 v12
      • v14 (9) = SelectN <mem> [0] v13
      • v15 (9) = CALLstatic <mem> {AuxCall{runtime.printunlock}} v14
      • v16 (9) = SelectN <mem> [0] v15
      • v17 (+10) = MakeResult <mem> v16
    • Ret v17 (10)
  • name float_64_b[float64]: v10

    • late nilcheck [1374 ns]

    flagalloc [4790 ns]

    regalloc [585820 ns]

    • b1:
      • v1 (?) = InitMem <mem>
      • v11 (+9) = CALLstatic <mem> {AuxCall{runtime.printlock}} v1
      • v12 (9) = SelectN <mem> [0] v11
      • v7 (9) = MOVSDconst <float64> [7] : X0
      • v13 (9) = CALLstatic <mem> {AuxCall{runtime.printfloat}} [8] v7 v12 : >
      • v14 (9) = SelectN <mem> [0] v13
      • v15 (9) = CALLstatic <mem> {AuxCall{runtime.printunlock}} v14
      • v16 (9) = SelectN <mem> [0] v15
      • v17 (+10) = MakeResult <mem> v16
    • Ret v17 (10)
  • name float_64_b[float64]: v10

    • loop rotate [275 ns]

    stackframe [4448 ns]

    trim [418 ns]

    • b1:
      • v1 (?) = InitMem <mem>
      • v11 (+9) = CALLstatic <mem> {AuxCall{runtime.printlock}} v1
      • v12 (9) = SelectN <mem> [0] v11
      • v7 (9) = MOVSDconst <float64> [7] : X0
      • v13 (9) = CALLstatic <mem> {AuxCall{runtime.printfloat}} [8] v7 v12 : >
      • v14 (9) = SelectN <mem> [0] v13
      • v15 (9) = CALLstatic <mem> {AuxCall{runtime.printunlock}} v14
      • v16 (9) = SelectN <mem> [0] v15
      • v17 (+10) = MakeResult <mem> v16
    • Ret v17 (10)
  • name float_64_b[float64]: v10

    • genssa

    # /Users/mohammed/projects/gopheradvent.com/site/content/calendar/2021/lisp-in-go/main.go
    00000 (3) TEXT "".main(SB), ABIInternal
    00001 (3) FUNCDATA $0, gclocals·33cdeccccebe80329f1fdbee7f5874cb(SB)
    00002 (3) FUNCDATA $1, gclocals·33cdeccccebe80329f1fdbee7f5874cb(SB)
    v11
    00003 (+9) PCDATA $1, $0
    v11
    00004 (+9) CALL runtime.printlock(SB)
    v7
    00005 (9) MOVSD $(7.0), X0
    v13
    00006 (9) CALL runtime.printfloat(SB)
    v15
    00007 (9) CALL runtime.printunlock(SB)
    b1
    00008 (10) RET
    00009 (?) END