mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2024-08-30 05:29:47 +00:00
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205959 91177308-0d34-0410-b5e6-96231b3b80d8
50 lines
1.3 KiB
C++
50 lines
1.3 KiB
C++
//===-- SaveAndRestore.h - Utility -------------------------------*- C++ -*-=//
|
|
//
|
|
// The LLVM Compiler Infrastructure
|
|
//
|
|
// This file is distributed under the University of Illinois Open Source
|
|
// License. See LICENSE.TXT for details.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
///
|
|
/// \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;
|
|
};
|
|
|
|
/// Similar to \c SaveAndRestore. Operates only on bools; the old value of a
|
|
/// variable is saved, and during the dstor the old value is or'ed with the new
|
|
/// value.
|
|
struct SaveOr {
|
|
SaveOr(bool &X) : X(X), OldValue(X) { X = false; }
|
|
~SaveOr() { X |= OldValue; }
|
|
|
|
private:
|
|
bool &X;
|
|
const bool OldValue;
|
|
};
|
|
|
|
} // namespace llvm
|
|
|
|
#endif
|