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[dev.ssa] cmd/compile: more 386 port changes

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Fix up zero/move code, including duff calls and rep movs.

Handle the new ops generated by dec64.rules.

Fix constant shifts.

Change-Id: I7d89194b29b04311bfafa0fd93b9f5644af04df9
Reviewed-on: https://go-review.googlesource.com/25033
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
This commit is contained in:
Keith Randall 2016-07-18 15:52:59 -07:00
parent 1b0404c4ca
commit 4a33af6bb6
9 changed files with 550 additions and 274 deletions
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45
src/cmd/compile/internal/ssa/rewrite.go
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@ -254,39 +254,38 @@ func isSamePtr(p1, p2 *Value) bool {
return false
}
// DUFFZERO consists of repeated blocks of 4 MOVUPSs + ADD,
// See runtime/mkduff.go.
const (
dzBlocks = 16 // number of MOV/ADD blocks
dzBlockLen = 4 // number of clears per block
dzBlockSize = 19 // size of instructions in a single block
dzMovSize = 4 // size of single MOV instruction w/ offset
dzAddSize = 4 // size of single ADD instruction
dzClearStep = 16 // number of bytes cleared by each MOV instruction
dzTailLen = 4 // number of final STOSQ instructions
dzTailSize = 2 // size of single STOSQ instruction
dzClearLen = dzClearStep * dzBlockLen // bytes cleared by one block
dzSize = dzBlocks * dzBlockSize
)
func duffStart(size int64) int64 {
x, _ := duff(size)
func duffStartAMD64(size int64) int64 {
x, _ := duffAMD64(size)
return x
}
func duffAdj(size int64) int64 {
_, x := duff(size)
func duffAdjAMD64(size int64) int64 {
_, x := duffAMD64(size)
return x
}
// duff returns the offset (from duffzero, in bytes) and pointer adjust (in bytes)
// required to use the duffzero mechanism for a block of the given size.
func duff(size int64) (int64, int64) {
func duffAMD64(size int64) (int64, int64) {
// DUFFZERO consists of repeated blocks of 4 MOVUPSs + ADD,
// See runtime/mkduff.go.
const (
dzBlocks = 16 // number of MOV/ADD blocks
dzBlockLen = 4 // number of clears per block
dzBlockSize = 19 // size of instructions in a single block
dzMovSize = 4 // size of single MOV instruction w/ offset
dzAddSize = 4 // size of single ADD instruction
dzClearStep = 16 // number of bytes cleared by each MOV instruction
dzTailLen = 4 // number of final STOSQ instructions
dzTailSize = 2 // size of single STOSQ instruction
dzClearLen = dzClearStep * dzBlockLen // bytes cleared by one block
dzSize = dzBlocks * dzBlockSize
)
if size < 32 || size > 1024 || size%dzClearStep != 0 {
panic("bad duffzero size")
}
// TODO: arch-dependent
steps := size / dzClearStep
blocks := steps / dzBlockLen
steps %= dzBlockLen