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go/test/codegen/floats.go
fanzha02 822a9f537f cmd/compile: fix the error of absorbing boolean tests into block(FGE, FGT)
The CL 164718 mistyped the comparison flags. The rules for floating
point comparison should be GreaterThanF and GreaterEqualF. Fortunately,
the wrong optimizations were overwritten by other integer rules, so the
issue won't cause failure but just some performance impact.

The fixed CL optimizes the floating point test as follows.

source code: func foo(f float64) bool { return f > 4 || f < -4}
previous version: "FCMPD", "CSET\tGT", "CBZ"
fixed version: "FCMPD", BLE"

Add the test case.

Change-Id: Iea954fdbb8272b2d642dae0f816dc77286e6e1fa
Reviewed-on: https://go-review.googlesource.com/c/go/+/177121
Reviewed-by: Ben Shi <powerman1st@163.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2019-05-16 13:46:25 +00:00

146 lines
3.1 KiB
Go

// asmcheck
// Copyright 2018 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package codegen
import "math"
// This file contains codegen tests related to arithmetic
// simplifications and optimizations on float types.
// For codegen tests on integer types, see arithmetic.go.
// --------------------- //
// Strength-reduce //
// --------------------- //
func Mul2(f float64) float64 {
// 386/sse2:"ADDSD",-"MULSD"
// 386/387:"FADDDP",-"FMULDP"
// amd64:"ADDSD",-"MULSD"
// arm/7:"ADDD",-"MULD"
// arm64:"FADDD",-"FMULD"
// ppc64:"FADD",-"FMUL"
// ppc64le:"FADD",-"FMUL"
return f * 2.0
}
func DivPow2(f1, f2, f3 float64) (float64, float64, float64) {
// 386/sse2:"MULSD",-"DIVSD"
// 386/387:"FMULDP",-"FDIVDP"
// amd64:"MULSD",-"DIVSD"
// arm/7:"MULD",-"DIVD"
// arm64:"FMULD",-"FDIVD"
// ppc64:"FMUL",-"FDIV"
// ppc64le:"FMUL",-"FDIV"
x := f1 / 16.0
// 386/sse2:"MULSD",-"DIVSD"
// 386/387:"FMULDP",-"FDIVDP"
// amd64:"MULSD",-"DIVSD"
// arm/7:"MULD",-"DIVD"
// arm64:"FMULD",-"FDIVD"
// ppc64:"FMUL",-"FDIVD"
// ppc64le:"FMUL",-"FDIVD"
y := f2 / 0.125
// 386/sse2:"ADDSD",-"DIVSD",-"MULSD"
// 386/387:"FADDDP",-"FDIVDP",-"FMULDP"
// amd64:"ADDSD",-"DIVSD",-"MULSD"
// arm/7:"ADDD",-"MULD",-"DIVD"
// arm64:"FADDD",-"FMULD",-"FDIVD"
// ppc64:"FADD",-"FMUL",-"FDIV"
// ppc64le:"FADD",-"FMUL",-"FDIV"
z := f3 / 0.5
return x, y, z
}
func getPi() float64 {
// 386/387:"FLDPI"
return math.Pi
}
func indexLoad(b0 []float32, b1 float32, idx int) float32 {
// arm64:`FMOVS\s\(R[0-9]+\)\(R[0-9]+\),\sF[0-9]+`
return b0[idx] * b1
}
func indexStore(b0 []float64, b1 float64, idx int) {
// arm64:`FMOVD\sF[0-9]+,\s\(R[0-9]+\)\(R[0-9]+\)`
b0[idx] = b1
}
// ----------- //
// Fused //
// ----------- //
func FusedAdd32(x, y, z float32) float32 {
// s390x:"FMADDS\t"
// ppc64:"FMADDS\t"
// ppc64le:"FMADDS\t"
// arm64:"FMADDS"
return x*y + z
}
func FusedSub32_a(x, y, z float32) float32 {
// s390x:"FMSUBS\t"
// ppc64:"FMSUBS\t"
// ppc64le:"FMSUBS\t"
return x*y - z
}
func FusedSub32_b(x, y, z float32) float32 {
// arm64:"FMSUBS"
return z - x*y
}
func FusedAdd64(x, y, z float64) float64 {
// s390x:"FMADD\t"
// ppc64:"FMADD\t"
// ppc64le:"FMADD\t"
// arm64:"FMADDD"
return x*y + z
}
func FusedSub64_a(x, y, z float64) float64 {
// s390x:"FMSUB\t"
// ppc64:"FMSUB\t"
// ppc64le:"FMSUB\t"
return x*y - z
}
func FusedSub64_b(x, y, z float64) float64 {
// arm64:"FMSUBD"
return z - x*y
}
func Cmp(f float64) bool {
// arm64:"FCMPD","BLE",-"CSET\tGT",-"CBZ"
return f > 4 || f < -4
}
// ---------------- //
// Non-floats //
// ---------------- //
// We should make sure that the compiler doesn't generate floating point
// instructions for non-float operations on Plan 9, because floating point
// operations are not allowed in the note handler.
func ArrayZero() [16]byte {
// amd64:"MOVUPS"
// plan9/amd64/:-"MOVUPS"
var a [16]byte
return a
}
func ArrayCopy(a [16]byte) (b [16]byte) {
// amd64:"MOVUPS"
// plan9/amd64/:-"MOVUPS"
b = a
return
}