mirror of
https://github.com/golang/go.git
synced 2025-12-08 06:10:04 +00:00
656f0888b7
Previously, softfloat mode does not work with register ABI, mainly because the compiler doesn't know how to pass floating point arguments and results. According to the ABI it should be passed in FP registers, but there isn't any in softfloat mode. This CL makes it work. When softfloat is used, we define the ABI as having 0 floating point registers (because there aren't any). The integer registers are unchanged. So floating point arguments and results are passed in memory. Another option is to pass (the bit representation of) floating point values in integer registers. But this complicates things because it'd need to reorder integer argument registers. Change-Id: Ibecbeccb658c10a868fa7f2dcf75138f719cc809 Reviewed-on: https://go-review.googlesource.com/c/go/+/327274 Trust: Cherry Mui <cherryyz@google.com> Run-TryBot: Cherry Mui <cherryyz@google.com> TryBot-Result: Go Bot <gobot@golang.org> Reviewed-by: David Chase <drchase@google.com>
80 lines
2 KiB
Go
80 lines
2 KiB
Go
// Copyright 2017 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 ssa
|
|
|
|
import (
|
|
"cmd/compile/internal/types"
|
|
"math"
|
|
)
|
|
|
|
func softfloat(f *Func) {
|
|
if !f.Config.SoftFloat {
|
|
return
|
|
}
|
|
newInt64 := false
|
|
|
|
for _, b := range f.Blocks {
|
|
for _, v := range b.Values {
|
|
if v.Type.IsFloat() {
|
|
f.unCache(v)
|
|
switch v.Op {
|
|
case OpPhi, OpLoad, OpArg:
|
|
if v.Type.Size() == 4 {
|
|
v.Type = f.Config.Types.UInt32
|
|
} else {
|
|
v.Type = f.Config.Types.UInt64
|
|
}
|
|
case OpConst32F:
|
|
v.Op = OpConst32
|
|
v.Type = f.Config.Types.UInt32
|
|
v.AuxInt = int64(int32(math.Float32bits(auxTo32F(v.AuxInt))))
|
|
case OpConst64F:
|
|
v.Op = OpConst64
|
|
v.Type = f.Config.Types.UInt64
|
|
case OpNeg32F:
|
|
arg0 := v.Args[0]
|
|
v.reset(OpXor32)
|
|
v.Type = f.Config.Types.UInt32
|
|
v.AddArg(arg0)
|
|
mask := v.Block.NewValue0(v.Pos, OpConst32, v.Type)
|
|
mask.AuxInt = -0x80000000
|
|
v.AddArg(mask)
|
|
case OpNeg64F:
|
|
arg0 := v.Args[0]
|
|
v.reset(OpXor64)
|
|
v.Type = f.Config.Types.UInt64
|
|
v.AddArg(arg0)
|
|
mask := v.Block.NewValue0(v.Pos, OpConst64, v.Type)
|
|
mask.AuxInt = -0x8000000000000000
|
|
v.AddArg(mask)
|
|
case OpRound32F:
|
|
v.Op = OpCopy
|
|
v.Type = f.Config.Types.UInt32
|
|
case OpRound64F:
|
|
v.Op = OpCopy
|
|
v.Type = f.Config.Types.UInt64
|
|
}
|
|
newInt64 = newInt64 || v.Type.Size() == 8
|
|
} else if (v.Op == OpStore || v.Op == OpZero || v.Op == OpMove) && v.Aux.(*types.Type).IsFloat() {
|
|
switch size := v.Aux.(*types.Type).Size(); size {
|
|
case 4:
|
|
v.Aux = f.Config.Types.UInt32
|
|
case 8:
|
|
v.Aux = f.Config.Types.UInt64
|
|
newInt64 = true
|
|
default:
|
|
v.Fatalf("bad float type with size %d", size)
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
if newInt64 && f.Config.RegSize == 4 {
|
|
// On 32bit arch, decompose Uint64 introduced in the switch above.
|
|
decomposeBuiltIn(f)
|
|
applyRewrite(f, rewriteBlockdec64, rewriteValuedec64, removeDeadValues)
|
|
}
|
|
|
|
}
|