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c292b32f33
Memmove can use AVX/prefetches/other optional instructions, so only do it for small sizes, when call overhead dominates. Change-Id: Ice5e93deb11462217f7fb5fc350b703109bb4090 Reviewed-on: https://go-review.googlesource.com/112517 Run-TryBot: Ilya Tocar <ilya.tocar@intel.com> TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Michael Munday <mike.munday@ibm.com>
84 lines
1.6 KiB
Go
84 lines
1.6 KiB
Go
// asmcheck
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// Copyright 2018 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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package codegen
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import "runtime"
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// Check small copies are replaced with moves.
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func movesmall4() {
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x := [...]byte{1, 2, 3, 4}
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// 386:-".*memmove"
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// amd64:-".*memmove"
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// arm:-".*memmove"
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// arm64:-".*memmove"
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copy(x[1:], x[:])
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}
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func movesmall7() {
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x := [...]byte{1, 2, 3, 4, 5, 6, 7}
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// 386:-".*memmove"
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// amd64:-".*memmove"
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// arm64:-".*memmove"
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copy(x[1:], x[:])
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}
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func movesmall16() {
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x := [...]byte{1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16}
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// amd64:-".*memmove"
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copy(x[1:], x[:])
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}
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var x [256]byte
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// Check that large disjoint copies are replaced with moves.
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func moveDisjointStack() {
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var s [256]byte
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// s390x:-".*memmove"
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// amd64:-".*memmove"
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copy(s[:], x[:])
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runtime.KeepAlive(&s)
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}
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func moveDisjointArg(b *[256]byte) {
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var s [256]byte
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// s390x:-".*memmove"
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// amd64:-".*memmove"
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copy(s[:], b[:])
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runtime.KeepAlive(&s)
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}
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func moveDisjointNoOverlap(a *[256]byte) {
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// s390x:-".*memmove"
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// amd64:-".*memmove"
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copy(a[:], a[128:])
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}
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// Check that no branches are generated when the pointers are [not] equal.
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func ptrEqual() {
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// amd64:-"JEQ",-"JNE"
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// ppc64le:-"BEQ",-"BNE"
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// s390x:-"BEQ",-"BNE"
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copy(x[:], x[:])
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}
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func ptrOneOffset() {
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// amd64:-"JEQ",-"JNE"
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// ppc64le:-"BEQ",-"BNE"
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// s390x:-"BEQ",-"BNE"
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copy(x[1:], x[:])
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}
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func ptrBothOffset() {
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// amd64:-"JEQ",-"JNE"
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// ppc64le:-"BEQ",-"BNE"
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// s390x:-"BEQ",-"BNE"
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copy(x[1:], x[2:])
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}
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