blob: 8cc5e4e19b0ae09d016bef2dbad640acb6a8cf33 (
plain) (
blame)
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
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
|
#pragma once
#ifdef __GNUC__
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wunused-parameter"
#endif
//===-- SaveAndRestore.h - Utility -------------------------------*- C++ -*-=//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
///
/// \file
/// This file provides utility classes that use RAII to save and restore
/// values.
///
//===----------------------------------------------------------------------===//
#ifndef LLVM_SUPPORT_SAVEANDRESTORE_H
#define LLVM_SUPPORT_SAVEANDRESTORE_H
#include <utility>
namespace llvm {
/// A utility class that uses RAII to save and restore the value of a variable.
template <typename T> struct SaveAndRestore {
SaveAndRestore(T &X) : X(X), OldValue(X) {}
SaveAndRestore(T &X, const T &NewValue) : X(X), OldValue(X) { X = NewValue; }
SaveAndRestore(T &X, T &&NewValue) : X(X), OldValue(std::move(X)) {
X = std::move(NewValue);
}
~SaveAndRestore() { X = std::move(OldValue); }
const T &get() { return OldValue; }
private:
T &X;
T OldValue;
};
// User-defined CTAD guides.
template <typename T> SaveAndRestore(T &) -> SaveAndRestore<T>;
template <typename T> SaveAndRestore(T &, const T &) -> SaveAndRestore<T>;
template <typename T> SaveAndRestore(T &, T &&) -> SaveAndRestore<T>;
} // namespace llvm
#endif
#ifdef __GNUC__
#pragma GCC diagnostic pop
#endif
|