/
clobberdead.go
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/
clobberdead.go
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// asmcheck -gcflags=-clobberdead
// +build amd64
// Copyright 2021 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
type T [2]*int // contain pointer, not SSA-able (so locals are not registerized)
var p1, p2, p3 T
func F() {
// 3735936685 is 0xdeaddead
// clobber x, y at entry. not clobber z (stack object).
// amd64:`MOVL\t\$3735936685, ""\.x`, `MOVL\t\$3735936685, ""\.y`, -`MOVL\t\$3735936685, ""\.z`
x, y, z := p1, p2, p3
addrTaken(&z)
// x is dead at the call (the value of x is loaded before the CALL), y is not
// amd64:`MOVL\t\$3735936685, ""\.x`, -`MOVL\t\$3735936685, ""\.y`
use(x)
// amd64:`MOVL\t\$3735936685, ""\.x`, `MOVL\t\$3735936685, ""\.y`
use(y)
}
//go:noinline
func use(T) {}
//go:noinline
func addrTaken(*T) {}