llvm/llvm/lib/Support/Atomic.cpp

//===-- Atomic.cpp - Atomic Operations --------------------------*- 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
//
//===----------------------------------------------------------------------===//
//
//  This file implements atomic operations.
//
//===----------------------------------------------------------------------===//

#include "llvm/Support/Atomic.h"
#include "llvm/Config/llvm-config.h"

usingnamespacellvm;

#if defined(_MSC_VER)
#include <intrin.h>

// We must include windows.h after intrin.h.
#include <windows.h>
#undef MemoryFence
#endif

#if defined(__GNUC__) || (defined(__IBMCPP__) && __IBMCPP__ >= 1210)
#define GNU_ATOMICS
#endif

void sys::MemoryFence() { … }

sys::cas_flag sys::CompareAndSwap(volatile sys::cas_flag* ptr,
                                  sys::cas_flag new_value,
                                  sys::cas_flag old_value) { … }