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go/test/codegen/copy.go

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cmd/compile/internal/ssa: inline small memmove for arm64 This patch enables the optimization for arm64 target. Performance results on Amberwing for strconv benchmark: name old time/op new time/op delta Quote 721ns ± 0% 617ns ± 0% -14.40% (p=0.016 n=5+4) QuoteRune 118ns ± 0% 117ns ± 0% -0.85% (p=0.008 n=5+5) AppendQuote 436ns ± 2% 321ns ± 0% -26.31% (p=0.008 n=5+5) AppendQuoteRune 34.7ns ± 0% 28.4ns ± 0% -18.16% (p=0.000 n=5+4) [Geo mean] 189ns 160ns -15.41% Change-Id: I5714c474e7483d07ca338fbaf49beb4bbcc11c44 Reviewed-on: https://go-review.googlesource.com/98735 Run-TryBot: Cherry Zhang <cherryyz@google.com> TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Giovanni Bajo <rasky@develer.com> Reviewed-by: Cherry Zhang <cherryyz@google.com>
2018-03-05 15:51:54 -05:00
// 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
cmd/compile: generate constants for NeqPtr, EqPtr and IsNonNil ops If both inputs are constant offsets from the same pointer then we can evaluate NeqPtr and EqPtr at compile time. Triggers a few times during all.bash. Removes a conditional branch in the following code: copy(x[1:], x[:]) This branch was recently added as an optimization in CL 94596. We now skip the memmove if the pointers are equal. However, in the above code we know at compile time that they are never equal. Also, when the offset is variable, check if the offset is zero rather than if the pointers are equal. For example: copy(x[a:], x[:]) This would now skip the copy if a == 0, rather than if x + a == x. Finally I've also added a rule to make IsNonNil true for pointers to values on the stack. The nil check elimination pass will catch these anyway, but eliminating them here might eliminate branches earlier. Change-Id: If72f436fef0a96ad0f4e296d3a1f8b6c3e712085 Reviewed-on: https://go-review.googlesource.com/106635 Run-TryBot: Michael Munday <mike.munday@ibm.com> TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Keith Randall <khr@golang.org>
2018-04-12 15:24:08 +01:00
// Check small copies are replaced with moves.
test/codegen: port all small memmove tests to codegen This change ports all the remaining tests checking that small memmoves are replaced with MOVs to the new codegen test harness, and deletes them from the asm_test file. Change-Id: I01c94b441e27a5d61518035af62d62779dafeb56 Reviewed-on: https://go-review.googlesource.com/100476 Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com> TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Keith Randall <khr@golang.org>
2018-03-14 11:07:06 +01:00
func movesmall4() {
x := [...]byte{1, 2, 3, 4}
// 386:-".*memmove"
// amd64:-".*memmove"
// arm:-".*memmove"
// arm64:-".*memmove"
copy(x[1:], x[:])
}
func movesmall7() {
cmd/compile/internal/ssa: inline small memmove for arm64 This patch enables the optimization for arm64 target. Performance results on Amberwing for strconv benchmark: name old time/op new time/op delta Quote 721ns ± 0% 617ns ± 0% -14.40% (p=0.016 n=5+4) QuoteRune 118ns ± 0% 117ns ± 0% -0.85% (p=0.008 n=5+5) AppendQuote 436ns ± 2% 321ns ± 0% -26.31% (p=0.008 n=5+5) AppendQuoteRune 34.7ns ± 0% 28.4ns ± 0% -18.16% (p=0.000 n=5+4) [Geo mean] 189ns 160ns -15.41% Change-Id: I5714c474e7483d07ca338fbaf49beb4bbcc11c44 Reviewed-on: https://go-review.googlesource.com/98735 Run-TryBot: Cherry Zhang <cherryyz@google.com> TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Giovanni Bajo <rasky@develer.com> Reviewed-by: Cherry Zhang <cherryyz@google.com>
2018-03-05 15:51:54 -05:00
x := [...]byte{1, 2, 3, 4, 5, 6, 7}
test/codegen: port all small memmove tests to codegen This change ports all the remaining tests checking that small memmoves are replaced with MOVs to the new codegen test harness, and deletes them from the asm_test file. Change-Id: I01c94b441e27a5d61518035af62d62779dafeb56 Reviewed-on: https://go-review.googlesource.com/100476 Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com> TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Keith Randall <khr@golang.org>
2018-03-14 11:07:06 +01:00
// 386:-".*memmove"
// amd64:-".*memmove"
// arm64:-".*memmove"
copy(x[1:], x[:])
}
func movesmall16() {
x := [...]byte{1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16}
// amd64:-".*memmove"
copy(x[1:], x[:])
cmd/compile/internal/ssa: inline small memmove for arm64 This patch enables the optimization for arm64 target. Performance results on Amberwing for strconv benchmark: name old time/op new time/op delta Quote 721ns ± 0% 617ns ± 0% -14.40% (p=0.016 n=5+4) QuoteRune 118ns ± 0% 117ns ± 0% -0.85% (p=0.008 n=5+5) AppendQuote 436ns ± 2% 321ns ± 0% -26.31% (p=0.008 n=5+5) AppendQuoteRune 34.7ns ± 0% 28.4ns ± 0% -18.16% (p=0.000 n=5+4) [Geo mean] 189ns 160ns -15.41% Change-Id: I5714c474e7483d07ca338fbaf49beb4bbcc11c44 Reviewed-on: https://go-review.googlesource.com/98735 Run-TryBot: Cherry Zhang <cherryyz@google.com> TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Giovanni Bajo <rasky@develer.com> Reviewed-by: Cherry Zhang <cherryyz@google.com>
2018-03-05 15:51:54 -05:00
}
cmd/compile: generate constants for NeqPtr, EqPtr and IsNonNil ops If both inputs are constant offsets from the same pointer then we can evaluate NeqPtr and EqPtr at compile time. Triggers a few times during all.bash. Removes a conditional branch in the following code: copy(x[1:], x[:]) This branch was recently added as an optimization in CL 94596. We now skip the memmove if the pointers are equal. However, in the above code we know at compile time that they are never equal. Also, when the offset is variable, check if the offset is zero rather than if the pointers are equal. For example: copy(x[a:], x[:]) This would now skip the copy if a == 0, rather than if x + a == x. Finally I've also added a rule to make IsNonNil true for pointers to values on the stack. The nil check elimination pass will catch these anyway, but eliminating them here might eliminate branches earlier. Change-Id: If72f436fef0a96ad0f4e296d3a1f8b6c3e712085 Reviewed-on: https://go-review.googlesource.com/106635 Run-TryBot: Michael Munday <mike.munday@ibm.com> TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Keith Randall <khr@golang.org>
2018-04-12 15:24:08 +01:00
// Check that no branches are generated when the pointers are [not] equal.
var x [256]byte
func ptrEqual() {
// amd64:-"JEQ",-"JNE"
// ppc64le:-"BEQ",-"BNE"
// s390x:-"BEQ",-"BNE"
copy(x[:], x[:])
}
func ptrOneOffset() {
// amd64:-"JEQ",-"JNE"
// ppc64le:-"BEQ",-"BNE"
// s390x:-"BEQ",-"BNE"
copy(x[1:], x[:])
}
func ptrBothOffset() {
// amd64:-"JEQ",-"JNE"
// ppc64le:-"BEQ",-"BNE"
// s390x:-"BEQ",-"BNE"
copy(x[1:], x[2:])
}
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