From 3a9d0ac3c807de9c6b91a91fa1e37f75da1941a8 Mon Sep 17 00:00:00 2001 From: David Chase Date: Fri, 28 Aug 2015 14:24:10 -0400 Subject: [PATCH] [dev.ssa] cmd/compile: add complex arithmetic Still to do: details, more testing corner cases. (e.g. negative zero) Includes small cleanups for previous CL. Note: complex division is currently done in the runtime, so the division code here is apparently not yet necessary and also not tested. Seems likely better to open code division and expose the widening/narrowing to optimization. Complex64 multiplication and division is done in wide format to avoid cancellation errors; for division, this also happens to be compatible with pre-SSA practice (which uses a single complex128 division function). It would-be-nice to widen for complex128 multiplication intermediates as well, but that is trickier to implement without a handy wider-precision format. Change-Id: I595a4300f68868fb7641852a54674c6b2b78855e Reviewed-on: https://go-review.googlesource.com/14028 Reviewed-by: Keith Randall --- src/cmd/compile/internal/gc/ssa.go | 153 ++++++++++++++++-- .../compile/internal/gc/testdata/fp_ssa.go | 102 +++++++++++- src/cmd/compile/internal/ssa/decompose.go | 9 +- src/cmd/compile/internal/ssa/gen/AMD64.rules | 2 + src/cmd/compile/internal/ssa/gen/AMD64Ops.go | 2 + .../compile/internal/ssa/gen/genericOps.go | 7 +- src/cmd/compile/internal/ssa/gen/rulegen.go | 3 + src/cmd/compile/internal/ssa/opGen.go | 24 +++ src/cmd/compile/internal/ssa/rewriteAMD64.go | 43 +++++ .../compile/internal/ssa/rewritegeneric.go | 3 + 10 files changed, 325 insertions(+), 23 deletions(-) diff --git a/src/cmd/compile/internal/gc/ssa.go b/src/cmd/compile/internal/gc/ssa.go index c0bff2a5f0..17288c3156 100644 --- a/src/cmd/compile/internal/gc/ssa.go +++ b/src/cmd/compile/internal/gc/ssa.go @@ -747,14 +747,16 @@ var opToSSA = map[opAndType]ssa.Op{ opAndType{ONOT, TBOOL}: ssa.OpNot, - opAndType{OMINUS, TINT8}: ssa.OpNeg8, - opAndType{OMINUS, TUINT8}: ssa.OpNeg8, - opAndType{OMINUS, TINT16}: ssa.OpNeg16, - opAndType{OMINUS, TUINT16}: ssa.OpNeg16, - opAndType{OMINUS, TINT32}: ssa.OpNeg32, - opAndType{OMINUS, TUINT32}: ssa.OpNeg32, - opAndType{OMINUS, TINT64}: ssa.OpNeg64, - opAndType{OMINUS, TUINT64}: ssa.OpNeg64, + opAndType{OMINUS, TINT8}: ssa.OpNeg8, + opAndType{OMINUS, TUINT8}: ssa.OpNeg8, + opAndType{OMINUS, TINT16}: ssa.OpNeg16, + opAndType{OMINUS, TUINT16}: ssa.OpNeg16, + opAndType{OMINUS, TINT32}: ssa.OpNeg32, + opAndType{OMINUS, TUINT32}: ssa.OpNeg32, + opAndType{OMINUS, TINT64}: ssa.OpNeg64, + opAndType{OMINUS, TUINT64}: ssa.OpNeg64, + opAndType{OMINUS, TFLOAT32}: ssa.OpNeg32F, + opAndType{OMINUS, TFLOAT64}: ssa.OpNeg64F, opAndType{OCOM, TINT8}: ssa.OpCom8, opAndType{OCOM, TUINT8}: ssa.OpCom8, @@ -953,6 +955,14 @@ func (s *state) ssaOp(op uint8, t *Type) ssa.Op { return x } +func floatForComplex(t *Type) *Type { + if t.Size() == 8 { + return Types[TFLOAT32] + } else { + return Types[TFLOAT64] + } +} + type opAndTwoTypes struct { op uint8 etype1 uint8 @@ -1394,7 +1404,24 @@ func (s *state) expr(n *Node) *ssa.Value { } return s.newValue1(op, n.Type, x) } - // TODO: Still lack complex conversions. + + if ft.IsComplex() && tt.IsComplex() { + var op ssa.Op + if ft.Size() == tt.Size() { + op = ssa.OpCopy + } else if ft.Size() == 8 && tt.Size() == 16 { + op = ssa.OpCvt32Fto64F + } else if ft.Size() == 16 && tt.Size() == 8 { + op = ssa.OpCvt64Fto32F + } else { + s.Fatalf("weird complex conversion %s -> %s", ft, tt) + } + ftp := floatForComplex(ft) + ttp := floatForComplex(tt) + return s.newValue2(ssa.OpComplexMake, tt, + s.newValue1(op, ttp, s.newValue1(ssa.OpComplexReal, ftp, x)), + s.newValue1(op, ttp, s.newValue1(ssa.OpComplexImag, ftp, x))) + } s.Unimplementedf("unhandled OCONV %s -> %s", Econv(int(n.Left.Type.Etype), 0), Econv(int(n.Type.Etype), 0)) return nil @@ -1404,7 +1431,97 @@ func (s *state) expr(n *Node) *ssa.Value { a := s.expr(n.Left) b := s.expr(n.Right) return s.newValue2(s.ssaOp(n.Op, n.Left.Type), Types[TBOOL], a, b) - case OADD, OAND, OMUL, OOR, OSUB, ODIV, OMOD, OHMUL, OXOR: + case OMUL: + a := s.expr(n.Left) + b := s.expr(n.Right) + if n.Type.IsComplex() { + mulop := ssa.OpMul64F + addop := ssa.OpAdd64F + subop := ssa.OpSub64F + pt := floatForComplex(n.Type) // Could be Float32 or Float64 + wt := Types[TFLOAT64] // Compute in Float64 to minimize cancellation error + + areal := s.newValue1(ssa.OpComplexReal, pt, a) + breal := s.newValue1(ssa.OpComplexReal, pt, b) + aimag := s.newValue1(ssa.OpComplexImag, pt, a) + bimag := s.newValue1(ssa.OpComplexImag, pt, b) + + if pt != wt { // Widen for calculation + areal = s.newValue1(ssa.OpCvt32Fto64F, wt, areal) + breal = s.newValue1(ssa.OpCvt32Fto64F, wt, breal) + aimag = s.newValue1(ssa.OpCvt32Fto64F, wt, aimag) + bimag = s.newValue1(ssa.OpCvt32Fto64F, wt, bimag) + } + + xreal := s.newValue2(subop, wt, s.newValue2(mulop, wt, areal, breal), s.newValue2(mulop, wt, aimag, bimag)) + ximag := s.newValue2(addop, wt, s.newValue2(mulop, wt, areal, bimag), s.newValue2(mulop, wt, aimag, breal)) + + if pt != wt { // Narrow to store back + xreal = s.newValue1(ssa.OpCvt64Fto32F, pt, xreal) + ximag = s.newValue1(ssa.OpCvt64Fto32F, pt, ximag) + } + + return s.newValue2(ssa.OpComplexMake, n.Type, xreal, ximag) + } + return s.newValue2(s.ssaOp(n.Op, n.Type), a.Type, a, b) + + case ODIV: + a := s.expr(n.Left) + b := s.expr(n.Right) + if n.Type.IsComplex() { + // TODO this is not executed because the front-end substitutes a runtime call. + // That probably ought to change; with modest optimization the widen/narrow + // conversions could all be elided in larger expression trees. + mulop := ssa.OpMul64F + addop := ssa.OpAdd64F + subop := ssa.OpSub64F + divop := ssa.OpDiv64F + pt := floatForComplex(n.Type) // Could be Float32 or Float64 + wt := Types[TFLOAT64] // Compute in Float64 to minimize cancellation error + + areal := s.newValue1(ssa.OpComplexReal, pt, a) + breal := s.newValue1(ssa.OpComplexReal, pt, b) + aimag := s.newValue1(ssa.OpComplexImag, pt, a) + bimag := s.newValue1(ssa.OpComplexImag, pt, b) + + if pt != wt { // Widen for calculation + areal = s.newValue1(ssa.OpCvt32Fto64F, wt, areal) + breal = s.newValue1(ssa.OpCvt32Fto64F, wt, breal) + aimag = s.newValue1(ssa.OpCvt32Fto64F, wt, aimag) + bimag = s.newValue1(ssa.OpCvt32Fto64F, wt, bimag) + } + + denom := s.newValue2(addop, wt, s.newValue2(mulop, wt, breal, breal), s.newValue2(mulop, wt, bimag, bimag)) + xreal := s.newValue2(addop, wt, s.newValue2(mulop, wt, areal, breal), s.newValue2(mulop, wt, aimag, bimag)) + ximag := s.newValue2(subop, wt, s.newValue2(mulop, wt, aimag, breal), s.newValue2(mulop, wt, areal, bimag)) + + // TODO not sure if this is best done in wide precision or narrow + // Double-rounding might be an issue. + // Note that the pre-SSA implementation does the entire calculation + // in wide format, so wide is compatible. + xreal = s.newValue2(divop, wt, xreal, denom) + ximag = s.newValue2(divop, wt, ximag, denom) + + if pt != wt { // Narrow to store back + xreal = s.newValue1(ssa.OpCvt64Fto32F, pt, xreal) + ximag = s.newValue1(ssa.OpCvt64Fto32F, pt, ximag) + } + + return s.newValue2(ssa.OpComplexMake, n.Type, xreal, ximag) + } + return s.newValue2(s.ssaOp(n.Op, n.Type), a.Type, a, b) + case OADD, OSUB: + a := s.expr(n.Left) + b := s.expr(n.Right) + if n.Type.IsComplex() { + pt := floatForComplex(n.Type) + op := s.ssaOp(n.Op, pt) + return s.newValue2(ssa.OpComplexMake, n.Type, + s.newValue2(op, pt, s.newValue1(ssa.OpComplexReal, pt, a), s.newValue1(ssa.OpComplexReal, pt, b)), + s.newValue2(op, pt, s.newValue1(ssa.OpComplexImag, pt, a), s.newValue1(ssa.OpComplexImag, pt, b))) + } + return s.newValue2(s.ssaOp(n.Op, n.Type), a.Type, a, b) + case OAND, OOR, OMOD, OHMUL, OXOR: a := s.expr(n.Left) b := s.expr(n.Right) return s.newValue2(s.ssaOp(n.Op, n.Type), a.Type, a, b) @@ -1464,8 +1581,18 @@ func (s *state) expr(n *Node) *ssa.Value { s.startBlock(bResult) return s.variable(n, Types[TBOOL]) - // unary ops - case ONOT, OMINUS, OCOM: + // unary ops + case OMINUS: + a := s.expr(n.Left) + if n.Type.IsComplex() { + tp := floatForComplex(n.Type) + negop := s.ssaOp(n.Op, tp) + return s.newValue2(ssa.OpComplexMake, n.Type, + s.newValue1(negop, tp, s.newValue1(ssa.OpComplexReal, tp, a)), + s.newValue1(negop, tp, s.newValue1(ssa.OpComplexImag, tp, a))) + } + return s.newValue1(s.ssaOp(n.Op, n.Type), a.Type, a) + case ONOT, OCOM: a := s.expr(n.Left) return s.newValue1(s.ssaOp(n.Op, n.Type), a.Type, a) @@ -2551,7 +2678,7 @@ func genValue(v *ssa.Value) { ssa.OpAMD64ORQ, ssa.OpAMD64ORL, ssa.OpAMD64ORW, ssa.OpAMD64ORB, ssa.OpAMD64XORQ, ssa.OpAMD64XORL, ssa.OpAMD64XORW, ssa.OpAMD64XORB, ssa.OpAMD64MULQ, ssa.OpAMD64MULL, ssa.OpAMD64MULW, ssa.OpAMD64MULB, - ssa.OpAMD64MULSS, ssa.OpAMD64MULSD: + ssa.OpAMD64MULSS, ssa.OpAMD64MULSD, ssa.OpAMD64PXOR: r := regnum(v) x := regnum(v.Args[0]) y := regnum(v.Args[1]) diff --git a/src/cmd/compile/internal/gc/testdata/fp_ssa.go b/src/cmd/compile/internal/gc/testdata/fp_ssa.go index c9eb23d371..2cbf00bab0 100644 --- a/src/cmd/compile/internal/gc/testdata/fp_ssa.go +++ b/src/cmd/compile/internal/gc/testdata/fp_ssa.go @@ -1306,7 +1306,7 @@ func fail32bool(s string, f func(a, b float32) bool, a, b float32, e bool) int { func expect64(s string, x, expected float64) int { if x != expected { - println("Expected", expected, "for", s, ", got", x) + println("F64 Expected", expected, "for", s, ", got", x) return 1 } return 0 @@ -1314,7 +1314,7 @@ func expect64(s string, x, expected float64) int { func expect32(s string, x, expected float32) int { if x != expected { - println("Expected", expected, "for", s, ", got", x) + println("F32 Expected", expected, "for", s, ", got", x) return 1 } return 0 @@ -1322,7 +1322,7 @@ func expect32(s string, x, expected float32) int { func expectUint64(s string, x, expected uint64) int { if x != expected { - fmt.Printf("%s: Expected 0x%016x, got 0x%016x\n", s, expected, x) + fmt.Printf("U64 Expected 0x%016x for %s, got 0x%016x\n", expected, s, x) return 1 } return 0 @@ -1435,6 +1435,100 @@ func cmpOpTest(s string, return fails } +func expectCx128(s string, x, expected complex128) int { + if x != expected { + println("Cx 128 Expected", expected, "for", s, ", got", x) + return 1 + } + return 0 +} + +func expectCx64(s string, x, expected complex64) int { + if x != expected { + println("Cx 64 Expected", expected, "for", s, ", got", x) + return 1 + } + return 0 +} + +func cx128sum_ssa(a, b complex128) complex128 { + return a + b +} + +func cx128diff_ssa(a, b complex128) complex128 { + return a - b +} + +func cx128prod_ssa(a, b complex128) complex128 { + return a * b +} + +func cx128quot_ssa(a, b complex128) complex128 { + return a / b +} + +func cx128neg_ssa(a complex128) complex128 { + return -a +} + +func cx64sum_ssa(a, b complex64) complex64 { + return a + b +} + +func cx64diff_ssa(a, b complex64) complex64 { + return a - b +} + +func cx64prod_ssa(a, b complex64) complex64 { + return a * b +} + +func cx64quot_ssa(a, b complex64) complex64 { + return a / b +} + +func cx64neg_ssa(a complex64) complex64 { + return -a +} + +func complexTest128() int { + fails := 0 + var a complex128 = 1 + 2i + var b complex128 = 3 + 6i + sum := cx128sum_ssa(b, a) + diff := cx128diff_ssa(b, a) + prod := cx128prod_ssa(b, a) + quot := cx128quot_ssa(b, a) + neg := cx128neg_ssa(a) + + fails += expectCx128("sum", sum, 4+8i) + fails += expectCx128("diff", diff, 2+4i) + fails += expectCx128("prod", prod, -9+12i) + fails += expectCx128("quot", quot, 3+0i) + fails += expectCx128("neg", neg, -1-2i) + + return fails +} + +func complexTest64() int { + fails := 0 + var a complex64 = 1 + 2i + var b complex64 = 3 + 6i + sum := cx64sum_ssa(b, a) + diff := cx64diff_ssa(b, a) + prod := cx64prod_ssa(b, a) + quot := cx64quot_ssa(b, a) + neg := cx64neg_ssa(a) + + fails += expectCx64("sum", sum, 4+8i) + fails += expectCx64("diff", diff, 2+4i) + fails += expectCx64("prod", prod, -9+12i) + fails += expectCx64("quot", quot, 3+0i) + fails += expectCx64("neg", neg, -1-2i) + + return fails +} + func main() { a := 3.0 @@ -1523,6 +1617,8 @@ func main() { } fails += floatingToIntegerConversionsTest() + fails += complexTest128() + fails += complexTest64() if fails > 0 { fmt.Printf("Saw %v failures\n", fails) diff --git a/src/cmd/compile/internal/ssa/decompose.go b/src/cmd/compile/internal/ssa/decompose.go index a2dfdc16ab..3ef20ef34f 100644 --- a/src/cmd/compile/internal/ssa/decompose.go +++ b/src/cmd/compile/internal/ssa/decompose.go @@ -77,12 +77,13 @@ func decomposeSlicePhi(v *Value) { func decomposeComplexPhi(v *Value) { fe := v.Block.Func.Config.fe var partType Type - if v.Type.Size() == 8 { + switch z := v.Type.Size(); z { + case 8: partType = fe.TypeFloat32() - } else if v.Type.Size() == 16 { + case 16: partType = fe.TypeFloat64() - } else { - panic("Whoops, are sizes in bytes or bits?") + default: + v.Fatalf("decomposeComplexPhi: bad complex size %d", z) } real := v.Block.NewValue0(v.Line, OpPhi, partType) diff --git a/src/cmd/compile/internal/ssa/gen/AMD64.rules b/src/cmd/compile/internal/ssa/gen/AMD64.rules index 46fb76f1dd..28ae88ff24 100644 --- a/src/cmd/compile/internal/ssa/gen/AMD64.rules +++ b/src/cmd/compile/internal/ssa/gen/AMD64.rules @@ -81,6 +81,8 @@ (Neg32 x) -> (NEGL x) (Neg16 x) -> (NEGW x) (Neg8 x) -> (NEGB x) +(Neg32F x) -> (PXOR x (MOVSSconst {math.Copysign(0, -1)})) +(Neg64F x) -> (PXOR x (MOVSDconst {math.Copysign(0, -1)})) (Com64 x) -> (NOTQ x) (Com32 x) -> (NOTL x) diff --git a/src/cmd/compile/internal/ssa/gen/AMD64Ops.go b/src/cmd/compile/internal/ssa/gen/AMD64Ops.go index f2c402a348..555a5149a7 100644 --- a/src/cmd/compile/internal/ssa/gen/AMD64Ops.go +++ b/src/cmd/compile/internal/ssa/gen/AMD64Ops.go @@ -354,6 +354,8 @@ func init() { {name: "CVTSD2SS", reg: fp11, asm: "CVTSD2SS"}, // convert float64 to float32 {name: "CVTSS2SD", reg: fp11, asm: "CVTSS2SD"}, // convert float32 to float64 + {name: "PXOR", reg: fp21, asm: "PXOR"}, // exclusive or, applied to X regs for float negation. + {name: "LEAQ", reg: gp11sb}, // arg0 + auxint + offset encoded in aux {name: "LEAQ1", reg: gp21sb}, // arg0 + arg1 + auxint {name: "LEAQ2", reg: gp21sb}, // arg0 + 2*arg1 + auxint diff --git a/src/cmd/compile/internal/ssa/gen/genericOps.go b/src/cmd/compile/internal/ssa/gen/genericOps.go index 8f6a858e43..d17f207a80 100644 --- a/src/cmd/compile/internal/ssa/gen/genericOps.go +++ b/src/cmd/compile/internal/ssa/gen/genericOps.go @@ -24,7 +24,6 @@ var genericOps = []opData{ {name: "SubPtr"}, {name: "Sub32F"}, {name: "Sub64F"}, - // TODO: Sub64C, Sub128C {name: "Mul8"}, // arg0 * arg1 {name: "Mul16"}, @@ -225,6 +224,8 @@ var genericOps = []opData{ {name: "Neg16"}, {name: "Neg32"}, {name: "Neg64"}, + {name: "Neg32F"}, + {name: "Neg64F"}, {name: "Com8"}, // ^arg0 {name: "Com16"}, @@ -336,8 +337,8 @@ var genericOps = []opData{ // Complex (part/whole) {name: "ComplexMake"}, // arg0=real, arg1=imag - {name: "ComplexReal"}, // real_part(arg0) - {name: "ComplexImag"}, // imaginary_part(arg0) + {name: "ComplexReal"}, // real(arg0) + {name: "ComplexImag"}, // imag(arg0) // Strings {name: "StringMake"}, // arg0=ptr, arg1=len diff --git a/src/cmd/compile/internal/ssa/gen/rulegen.go b/src/cmd/compile/internal/ssa/gen/rulegen.go index d98ad2587f..5dcbf1ee1c 100644 --- a/src/cmd/compile/internal/ssa/gen/rulegen.go +++ b/src/cmd/compile/internal/ssa/gen/rulegen.go @@ -142,6 +142,9 @@ func genRules(arch arch) { if *genLog { fmt.Fprintln(w, "import \"fmt\"") } + fmt.Fprintln(w, "import \"math\"") + fmt.Fprintln(w, "var _ = math.MinInt8 // in case not otherwise used") + fmt.Fprintf(w, "func rewriteValue%s(v *Value, config *Config) bool {\n", arch.name) fmt.Fprintln(w, "b := v.Block") diff --git a/src/cmd/compile/internal/ssa/opGen.go b/src/cmd/compile/internal/ssa/opGen.go index 51a998e352..a41b04b29f 100644 --- a/src/cmd/compile/internal/ssa/opGen.go +++ b/src/cmd/compile/internal/ssa/opGen.go @@ -237,6 +237,7 @@ const ( OpAMD64CVTSQ2SD OpAMD64CVTSD2SS OpAMD64CVTSS2SD + OpAMD64PXOR OpAMD64LEAQ OpAMD64LEAQ1 OpAMD64LEAQ2 @@ -435,6 +436,8 @@ const ( OpNeg16 OpNeg32 OpNeg64 + OpNeg32F + OpNeg64F OpCom8 OpCom16 OpCom32 @@ -2794,6 +2797,19 @@ var opcodeTable = [...]opInfo{ }, }, }, + { + name: "PXOR", + asm: x86.APXOR, + reg: regInfo{ + inputs: []inputInfo{ + {0, 4294901760}, // .X0 .X1 .X2 .X3 .X4 .X5 .X6 .X7 .X8 .X9 .X10 .X11 .X12 .X13 .X14 .X15 + {1, 4294901760}, // .X0 .X1 .X2 .X3 .X4 .X5 .X6 .X7 .X8 .X9 .X10 .X11 .X12 .X13 .X14 .X15 + }, + outputs: []regMask{ + 4294901760, // .X0 .X1 .X2 .X3 .X4 .X5 .X6 .X7 .X8 .X9 .X10 .X11 .X12 .X13 .X14 .X15 + }, + }, + }, { name: "LEAQ", reg: regInfo{ @@ -3743,6 +3759,14 @@ var opcodeTable = [...]opInfo{ name: "Neg64", generic: true, }, + { + name: "Neg32F", + generic: true, + }, + { + name: "Neg64F", + generic: true, + }, { name: "Com8", generic: true, diff --git a/src/cmd/compile/internal/ssa/rewriteAMD64.go b/src/cmd/compile/internal/ssa/rewriteAMD64.go index e089028258..67ec747e20 100644 --- a/src/cmd/compile/internal/ssa/rewriteAMD64.go +++ b/src/cmd/compile/internal/ssa/rewriteAMD64.go @@ -2,6 +2,9 @@ // generated with: cd gen; go run *.go package ssa +import "math" + +var _ = math.MinInt8 // in case not otherwise used func rewriteValueAMD64(v *Value, config *Config) bool { b := v.Block switch v.Op { @@ -6059,6 +6062,26 @@ func rewriteValueAMD64(v *Value, config *Config) bool { goto endce1f7e17fc193f6c076e47d5e401e126 endce1f7e17fc193f6c076e47d5e401e126: ; + case OpNeg32F: + // match: (Neg32F x) + // cond: + // result: (PXOR x (MOVSSconst {math.Copysign(0, -1)})) + { + x := v.Args[0] + v.Op = OpAMD64PXOR + v.AuxInt = 0 + v.Aux = nil + v.resetArgs() + v.AddArg(x) + v0 := b.NewValue0(v.Line, OpAMD64MOVSSconst, TypeInvalid) + v0.Type = config.Frontend().TypeFloat32() + v0.Aux = math.Copysign(0, -1) + v.AddArg(v0) + return true + } + goto end47074133a76e069317ceca46372cafc3 + end47074133a76e069317ceca46372cafc3: + ; case OpNeg64: // match: (Neg64 x) // cond: @@ -6075,6 +6098,26 @@ func rewriteValueAMD64(v *Value, config *Config) bool { goto enda06c5b1718f2b96aba10bf5a5c437c6c enda06c5b1718f2b96aba10bf5a5c437c6c: ; + case OpNeg64F: + // match: (Neg64F x) + // cond: + // result: (PXOR x (MOVSDconst {math.Copysign(0, -1)})) + { + x := v.Args[0] + v.Op = OpAMD64PXOR + v.AuxInt = 0 + v.Aux = nil + v.resetArgs() + v.AddArg(x) + v0 := b.NewValue0(v.Line, OpAMD64MOVSDconst, TypeInvalid) + v0.Type = config.Frontend().TypeFloat64() + v0.Aux = math.Copysign(0, -1) + v.AddArg(v0) + return true + } + goto end9240202f5753ebd23f11f982ece3e06e + end9240202f5753ebd23f11f982ece3e06e: + ; case OpNeg8: // match: (Neg8 x) // cond: diff --git a/src/cmd/compile/internal/ssa/rewritegeneric.go b/src/cmd/compile/internal/ssa/rewritegeneric.go index 09f03f985f..ca771d75ae 100644 --- a/src/cmd/compile/internal/ssa/rewritegeneric.go +++ b/src/cmd/compile/internal/ssa/rewritegeneric.go @@ -2,6 +2,9 @@ // generated with: cd gen; go run *.go package ssa +import "math" + +var _ = math.MinInt8 // in case not otherwise used func rewriteValuegeneric(v *Value, config *Config) bool { b := v.Block switch v.Op {