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ffb20631fc
Duffcopy now uses X0, as of 5cf281a. Teach the peephole
optimizer that duffcopy clobbers X0 so that it does not
rename registers use X0 across the duffcopy instruction.
Fixes #13171
Change-Id: I389cbf1982cb6eb2f51e6152ac96736a8589f085
Reviewed-on: https://go-review.googlesource.com/16715
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Minux Ma <minux@golang.org>
Reviewed-by: Ilya Tocar <ilya.tocar@intel.com>
35 lines
589 B
Go
35 lines
589 B
Go
// run
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// Copyright 2015 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 main
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// Make sure the compiler knows that DUFFCOPY clobbers X0
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import "fmt"
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//go:noinline
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func f(x float64) float64 {
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// y is allocated to X0
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y := x + 5
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// marshals z before y. Marshalling z
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// calls DUFFCOPY.
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return g(z, y)
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}
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//go:noinline
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func g(b [64]byte, y float64) float64 {
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return y
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}
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var z [64]byte
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func main() {
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got := f(5)
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if got != 10 {
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panic(fmt.Sprintf("want 10, got %f", got))
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}
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}
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