blob: 5a2a1a2c3704b3750437f72ad2b1f0e5d9777e28 [file] [log] [blame]
// Copyright 2015 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.
// Support for memory sanitizer. See runtime/cgo/mmap.go.
// +build linux,amd64
package runtime
import "unsafe"
// _cgo_mmap is filled in by runtime/cgo when it is linked into the
// program, so it is only non-nil when using cgo.
//go:linkname _cgo_mmap _cgo_mmap
var _cgo_mmap unsafe.Pointer
func mmap(addr unsafe.Pointer, n uintptr, prot, flags, fd int32, off uint32) unsafe.Pointer {
if _cgo_mmap != nil {
// Make ret a uintptr so that writing to it in the
// function literal does not trigger a write barrier.
// A write barrier here could break because of the way
// that mmap uses the same value both as a pointer and
// an errno value.
// TODO: Fix mmap to return two values.
var ret uintptr
systemstack(func() {
ret = callCgoMmap(addr, n, prot, flags, fd, off)
})
return unsafe.Pointer(ret)
}
return sysMmap(addr, n, prot, flags, fd, off)
}
// sysMmap calls the mmap system call. It is implemented in assembly.
func sysMmap(addr unsafe.Pointer, n uintptr, prot, flags, fd int32, off uint32) unsafe.Pointer
// callCgoMmap calls the mmap function in the runtime/cgo package
// using the GCC calling convention. It is implemented in assembly.
func callCgoMmap(addr unsafe.Pointer, n uintptr, prot, flags, fd int32, off uint32) uintptr