93 lines
3.0 KiB
C++
93 lines
3.0 KiB
C++
/*
|
|
* 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>
|