vn-verdnaturachat/ios/Pods/Flipper-Folly/folly/synchronization/AtomicUtil.h

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/*
* Copyright (c) Facebook, Inc. and its affiliates.
*
* 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.
*/
#pragma once
#include <atomic>
#include <cstdint>
namespace folly {
// atomic_compare_exchange_weak_explicit
//
// Fix TSAN bug in std::atomic_compare_exchange_weak_explicit.
// Workaround for https://github.com/google/sanitizers/issues/970.
//
// mimic: std::atomic_compare_exchange_weak
template <typename T>
bool atomic_compare_exchange_weak_explicit(
std::atomic<T>* obj,
T* expected,
T desired,
std::memory_order succ,
std::memory_order fail);
// atomic_compare_exchange_strong_explicit
//
// Fix TSAN bug in std::atomic_compare_exchange_strong_explicit.
// Workaround for https://github.com/google/sanitizers/issues/970.
//
// mimic: std::atomic_compare_exchange_strong
template <typename T>
bool atomic_compare_exchange_strong_explicit(
std::atomic<T>* obj,
T* expected,
T desired,
std::memory_order succ,
std::memory_order fail);
// atomic_fetch_set
//
// Sets the bit at the given index in the binary representation of the integer
// to 1. Returns the previous value of the bit, which is equivalent to whether
// that bit is unchanged.
//
// Equivalent to Atomic::fetch_or with a mask. For example, if the bit
// argument to this function is 1, the mask passed to the corresponding
// Atomic::fetch_or would be 0b1.
//
// Uses an optimized implementation when available, otherwise falling back to
// Atomic::fetch_or with mask. The optimization is currently available for
// std::atomic on x86, using the bts instruction.
template <typename Atomic>
bool atomic_fetch_set(
Atomic& atomic,
std::size_t bit,
std::memory_order order = std::memory_order_seq_cst);
// atomic_fetch_reset
//
// Resets the bit at the given index in the binary representation of the
// integer to 0. Returns the previous value of the bit, which is equivalent to
// whether that bit is changed.
//
// Equivalent to Atomic::fetch_and with a mask. For example, if the bit
// argument to this function is 1, the mask passed to the corresponding
// Atomic::fetch_and would be ~0b1.
//
// Uses an optimized implementation when available, otherwise falling back to
// Atomic::fetch_and with mask. The optimization is currently available for
// std::atomic on x86, using the btr instruction.
template <typename Atomic>
bool atomic_fetch_reset(
Atomic& atomic,
std::size_t bit,
std::memory_order order = std::memory_order_seq_cst);
} // namespace folly
#include <folly/synchronization/AtomicUtil-inl.h>