mirror of
https://github.com/golang/go
synced 2024-09-23 17:20:13 -06:00
8628bf9a97
This CL resurrects the clobberdead debugging mode (CL 23924). When -clobberdead flag is set (TODO: make it GOEXPERIMENT?), the compiler inserts code that clobbers all dead stack slots that contains pointers. Mark windows syscall functions cgo_unsafe_args, as the code actually does that, by taking the address of one argument and passing it to cgocall. Change-Id: Ie09a015f4bd14ae6053cc707866e30ae509b9d6f Reviewed-on: https://go-review.googlesource.com/c/go/+/301791 Trust: Cherry Zhang <cherryyz@google.com> Run-TryBot: Cherry Zhang <cherryyz@google.com> TryBot-Result: Go Bot <gobot@golang.org> Reviewed-by: David Chase <drchase@google.com> Reviewed-by: Than McIntosh <thanm@google.com>
33 lines
860 B
Go
33 lines
860 B
Go
// 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) {}
|