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/* Copyright 2012 10gen Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/**
* WARNING(schwerin): Use with extreme caution. Prefer the AtomicWord<> types from atomic_word.h.
*
* The atomic_intrinsics module provides low-level atomic operations for manipulating memory.
* Implementations are platform specific, so this file describes the interface and includes
* the appropriate os/compiler-specific headers.
*
* For supported word types, the atomic_intrinsics headers provide implementations of template
* classes of the following form:
*
* template <typename T> class AtomicIntrinsics {
* static T load(volatile const T* value);
* static T store(volatile T* dest, T newValue);
* static T compareAndSwap(volatile T* dest, T expected, T newValue);
* static T swap(volatile T* dest, T newValue);
* static T fetchAndAdd(volatile T* dest, T increment);
* };
*
* All of the functions assume that the volatile T pointers are naturally aligned, and may not
* operate as expected, if they are not so aligned.
*
* The behavior of the functions is analogous to the same-named member functions of the AtomicWord
* template type in atomic_word.h.
*/
#pragma once
#if defined(_WIN32)
#include "mongo/platform/atomic_intrinsics_win32.h"
#elif defined(__GNUC__)
#if defined(HAVE_GCC_ATOMIC_BUILTINS)
#include "mongo/platform/atomic_intrinsics_gcc_generic.h"
#elif defined(__i386__) || defined(__x86_64__)
#include "mongo/platform/atomic_intrinsics_gcc_intel.h"
#else
#error "Unsupported platform: no gcc atomic builtins or port available"
#endif
#else
#error "Unsupported os/compiler family"
#endif
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