1
0
mirror of https://github.com/golang/go synced 2024-11-14 20:40:32 -07:00
go/test/codegen/math.go
Russ Cox 543c6d2e0d math, cmd/compile: rename Fma to FMA
This API was added for #25819, where it was discussed as math.FMA.
The commit adding it used math.Fma, presumably for consistency
with the rest of the unusual names in package math
(Sincos, Acosh, Erfcinv, Float32bits, etc).

I believe that using an idiomatic Go name is more important here
than consistency with these other names, most of which are historical
baggage from C's standard library.

Early additions like Float32frombits happened before "uppercase for export"
(so they were originally like "float32frombits") and they were not properly
reconsidered when we uppercased the symbols to export them.
That's a mistake we live with.

The names of functions we have added since then, and even a few
that were legacy, are more properly Go-cased, such as IsNaN, IsInf,
and RoundToEven, rather than Isnan, Isinf, and Roundtoeven.
And also constants like MaxFloat32.

For new API, we should keep using proper Go-cased symbols
instead of minimally-upper-cased-C symbols.

So math.FMA, not math.Fma.

This API has not yet been released, so this change does not break
the compatibility promise.

This CL also modifies cmd/compile, since the compiler knows
the name of the function. I could have stopped at changing the
string constants, but it seemed to make more sense to use a
consistent casing everywhere.

Change-Id: I0f6f3407f41e99bfa8239467345c33945088896e
Reviewed-on: https://go-review.googlesource.com/c/go/+/205317
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2019-11-07 14:51:06 +00:00

189 lines
4.5 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"
var sink64 [8]float64
func approx(x float64) {
// s390x:"FIDBR\t[$]6"
// arm64:"FRINTPD"
// ppc64:"FRIP"
// ppc64le:"FRIP"
// wasm:"F64Ceil"
sink64[0] = math.Ceil(x)
// s390x:"FIDBR\t[$]7"
// arm64:"FRINTMD"
// ppc64:"FRIM"
// ppc64le:"FRIM"
// wasm:"F64Floor"
sink64[1] = math.Floor(x)
// s390x:"FIDBR\t[$]1"
// arm64:"FRINTAD"
// ppc64:"FRIN"
// ppc64le:"FRIN"
sink64[2] = math.Round(x)
// s390x:"FIDBR\t[$]5"
// arm64:"FRINTZD"
// ppc64:"FRIZ"
// ppc64le:"FRIZ"
// wasm:"F64Trunc"
sink64[3] = math.Trunc(x)
// s390x:"FIDBR\t[$]4"
// arm64:"FRINTND"
// wasm:"F64Nearest"
sink64[4] = math.RoundToEven(x)
}
func sqrt(x float64) float64 {
// amd64:"SQRTSD"
// 386/387:"FSQRT" 386/sse2:"SQRTSD"
// arm64:"FSQRTD"
// arm/7:"SQRTD"
// mips/hardfloat:"SQRTD" mips/softfloat:-"SQRTD"
// mips64/hardfloat:"SQRTD" mips64/softfloat:-"SQRTD"
// wasm:"F64Sqrt"
return math.Sqrt(x)
}
// Check that it's using integer registers
func abs(x, y float64) {
// amd64:"BTRQ\t[$]63"
// arm64:"FABSD\t"
// s390x:"LPDFR\t",-"MOVD\t" (no integer load/store)
// ppc64:"FABS\t"
// ppc64le:"FABS\t"
// wasm:"F64Abs"
// arm/6:"ABSD\t"
sink64[0] = math.Abs(x)
// amd64:"BTRQ\t[$]63","PXOR" (TODO: this should be BTSQ)
// s390x:"LNDFR\t",-"MOVD\t" (no integer load/store)
// ppc64:"FNABS\t"
// ppc64le:"FNABS\t"
sink64[1] = -math.Abs(y)
}
// Check that it's using integer registers
func abs32(x float32) float32 {
// s390x:"LPDFR",-"LDEBR",-"LEDBR" (no float64 conversion)
return float32(math.Abs(float64(x)))
}
// Check that it's using integer registers
func copysign(a, b, c float64) {
// amd64:"BTRQ\t[$]63","ANDQ","ORQ"
// s390x:"CPSDR",-"MOVD" (no integer load/store)
// ppc64:"FCPSGN"
// ppc64le:"FCPSGN"
// wasm:"F64Copysign"
sink64[0] = math.Copysign(a, b)
// amd64:"BTSQ\t[$]63"
// s390x:"LNDFR\t",-"MOVD\t" (no integer load/store)
// ppc64:"FCPSGN"
// ppc64le:"FCPSGN"
// arm64:"ORR", -"AND"
sink64[1] = math.Copysign(c, -1)
// Like math.Copysign(c, -1), but with integer operations. Useful
// for platforms that have a copysign opcode to see if it's detected.
// s390x:"LNDFR\t",-"MOVD\t" (no integer load/store)
sink64[2] = math.Float64frombits(math.Float64bits(a) | 1<<63)
// amd64:"ANDQ","ORQ"
// s390x:"CPSDR\t",-"MOVD\t" (no integer load/store)
// ppc64:"FCPSGN"
// ppc64le:"FCPSGN"
sink64[3] = math.Copysign(-1, c)
}
func fma(x, y, z float64) float64 {
// amd64:"VFMADD231SD"
// arm/6:"FMULAD"
// arm64:"FMADDD"
// s390x:"FMADD"
// ppc64:"FMADD"
// ppc64le:"FMADD"
return math.FMA(x, y, z)
}
func fromFloat64(f64 float64) uint64 {
// amd64:"MOVQ\tX.*, [^X].*"
// arm64:"FMOVD\tF.*, R.*"
// ppc64:"MFVSRD"
// ppc64le:"MFVSRD"
return math.Float64bits(f64+1) + 1
}
func fromFloat32(f32 float32) uint32 {
// amd64:"MOVL\tX.*, [^X].*"
// arm64:"FMOVS\tF.*, R.*"
return math.Float32bits(f32+1) + 1
}
func toFloat64(u64 uint64) float64 {
// amd64:"MOVQ\t[^X].*, X.*"
// arm64:"FMOVD\tR.*, F.*"
// ppc64:"MTVSRD"
// ppc64le:"MTVSRD"
return math.Float64frombits(u64+1) + 1
}
func toFloat32(u32 uint32) float32 {
// amd64:"MOVL\t[^X].*, X.*"
// arm64:"FMOVS\tR.*, F.*"
return math.Float32frombits(u32+1) + 1
}
// Test that comparisons with constants converted to float
// are evaluated at compile-time
func constantCheck64() bool {
// amd64:"MOVB\t[$]0",-"FCMP",-"MOVB\t[$]1"
// s390x:"MOV(B|BZ|D)\t[$]0,",-"FCMPU",-"MOV(B|BZ|D)\t[$]1,"
return 0.5 == float64(uint32(1)) || 1.5 > float64(uint64(1<<63)) || math.NaN() == math.NaN()
}
func constantCheck32() bool {
// amd64:"MOVB\t[$]1",-"FCMP",-"MOVB\t[$]0"
// s390x:"MOV(B|BZ|D)\t[$]1,",-"FCMPU",-"MOV(B|BZ|D)\t[$]0,"
return float32(0.5) <= float32(int64(1)) && float32(1.5) >= float32(int32(-1<<31)) && float32(math.NaN()) != float32(math.NaN())
}
// Test that integer constants are converted to floating point constants
// at compile-time
func constantConvert32(x float32) float32 {
// amd64:"MOVSS\t[$]f32.3f800000\\(SB\\)"
// s390x:"FMOVS\t[$]f32.3f800000\\(SB\\)"
// ppc64:"FMOVS\t[$]f32.3f800000\\(SB\\)"
// ppc64le:"FMOVS\t[$]f32.3f800000\\(SB\\)"
// arm64:"FMOVS\t[$]\\(1.0\\)"
if x > math.Float32frombits(0x3f800000) {
return -x
}
return x
}
func constantConvertInt32(x uint32) uint32 {
// amd64:-"MOVSS"
// s390x:-"FMOVS"
// ppc64:-"FMOVS"
// ppc64le:-"FMOVS"
// arm64:-"FMOVS"
if x > math.Float32bits(1) {
return -x
}
return x
}