blob: 8cdae1438e8578418d4e5b69eef047fb2123ff85 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
|
// Copyright 2024 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 abi
import "unsafe"
// NoEscape hides the pointer p from escape analysis, preventing it
// from escaping to the heap. It compiles down to nothing.
//
// WARNING: This is very subtle to use correctly. The caller must
// ensure that it's truly safe for p to not escape to the heap by
// maintaining runtime pointer invariants (for example, that globals
// and the heap may not generally point into a stack).
//
//go:nosplit
//go:nocheckptr
func NoEscape(p unsafe.Pointer) unsafe.Pointer {
x := uintptr(p)
return unsafe.Pointer(x ^ 0)
}
var alwaysFalse bool
var escapeSink any
// Escape forces any pointers in x to escape to the heap.
func Escape[T any](x T) T {
if alwaysFalse {
escapeSink = x
}
return x
}
|
