| //===-- 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 |
| |
| 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() { X = OldValue; } |
| T get() { return OldValue; } |
| |
| private: |
| T &X; |
| T OldValue; |
| }; |
| |
| } // namespace llvm |
| |
| #endif |