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// Copyright (c) 2011 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
// This file is an internal atomic implementation, use base/atomicops.h instead.
#ifndef BASE_ATOMICOPS_INTERNALS_X86_MACOSX_H_
#define BASE_ATOMICOPS_INTERNALS_X86_MACOSX_H_
#pragma once
#include <libkern/OSAtomic.h>
namespace base {
namespace subtle {
inline Atomic32 NoBarrier_CompareAndSwap(volatile Atomic32 *ptr,
Atomic32 old_value,
Atomic32 new_value) {
Atomic32 prev_value;
do {
if (OSAtomicCompareAndSwap32(old_value, new_value,
const_cast<Atomic32*>(ptr))) {
return old_value;
}
prev_value = *ptr;
} while (prev_value == old_value);
return prev_value;
}
inline Atomic32 NoBarrier_AtomicExchange(volatile Atomic32 *ptr,
Atomic32 new_value) {
Atomic32 old_value;
do {
old_value = *ptr;
} while (!OSAtomicCompareAndSwap32(old_value, new_value,
const_cast<Atomic32*>(ptr)));
return old_value;
}
inline Atomic32 NoBarrier_AtomicIncrement(volatile Atomic32 *ptr,
Atomic32 increment) {
return OSAtomicAdd32(increment, const_cast<Atomic32*>(ptr));
}
inline Atomic32 Barrier_AtomicIncrement(volatile Atomic32 *ptr,
Atomic32 increment) {
return OSAtomicAdd32Barrier(increment, const_cast<Atomic32*>(ptr));
}
inline void MemoryBarrier() {
OSMemoryBarrier();
}
inline Atomic32 Acquire_CompareAndSwap(volatile Atomic32 *ptr,
Atomic32 old_value,
Atomic32 new_value) {
Atomic32 prev_value;
do {
if (OSAtomicCompareAndSwap32Barrier(old_value, new_value,
const_cast<Atomic32*>(ptr))) {
return old_value;
}
prev_value = *ptr;
} while (prev_value == old_value);
return prev_value;
}
inline Atomic32 Release_CompareAndSwap(volatile Atomic32 *ptr,
Atomic32 old_value,
Atomic32 new_value) {
return Acquire_CompareAndSwap(ptr, old_value, new_value);
}
inline void NoBarrier_Store(volatile Atomic32* ptr, Atomic32 value) {
*ptr = value;
}
inline void Acquire_Store(volatile Atomic32 *ptr, Atomic32 value) {
*ptr = value;
MemoryBarrier();
}
inline void Release_Store(volatile Atomic32 *ptr, Atomic32 value) {
MemoryBarrier();
*ptr = value;
}
inline Atomic32 NoBarrier_Load(volatile const Atomic32* ptr) {
return *ptr;
}
inline Atomic32 Acquire_Load(volatile const Atomic32 *ptr) {
Atomic32 value = *ptr;
MemoryBarrier();
return value;
}
inline Atomic32 Release_Load(volatile const Atomic32 *ptr) {
MemoryBarrier();
return *ptr;
}
#ifdef __LP64__
// 64-bit implementation on 64-bit platform
inline Atomic64 NoBarrier_CompareAndSwap(volatile Atomic64 *ptr,
Atomic64 old_value,
Atomic64 new_value) {
Atomic64 prev_value;
do {
if (OSAtomicCompareAndSwap64(old_value, new_value,
reinterpret_cast<volatile int64_t*>(ptr))) {
return old_value;
}
prev_value = *ptr;
} while (prev_value == old_value);
return prev_value;
}
inline Atomic64 NoBarrier_AtomicExchange(volatile Atomic64 *ptr,
Atomic64 new_value) {
Atomic64 old_value;
do {
old_value = *ptr;
} while (!OSAtomicCompareAndSwap64(old_value, new_value,
reinterpret_cast<volatile int64_t*>(ptr)));
return old_value;
}
inline Atomic64 NoBarrier_AtomicIncrement(volatile Atomic64 *ptr,
Atomic64 increment) {
return OSAtomicAdd64(increment, reinterpret_cast<volatile int64_t*>(ptr));
}
inline Atomic64 Barrier_AtomicIncrement(volatile Atomic64 *ptr,
Atomic64 increment) {
return OSAtomicAdd64Barrier(increment,
reinterpret_cast<volatile int64_t*>(ptr));
}
inline Atomic64 Acquire_CompareAndSwap(volatile Atomic64 *ptr,
Atomic64 old_value,
Atomic64 new_value) {
Atomic64 prev_value;
do {
if (OSAtomicCompareAndSwap64Barrier(
old_value, new_value, reinterpret_cast<volatile int64_t*>(ptr))) {
return old_value;
}
prev_value = *ptr;
} while (prev_value == old_value);
return prev_value;
}
inline Atomic64 Release_CompareAndSwap(volatile Atomic64 *ptr,
Atomic64 old_value,
Atomic64 new_value) {
// The lib kern interface does not distinguish between
// Acquire and Release memory barriers; they are equivalent.
return Acquire_CompareAndSwap(ptr, old_value, new_value);
}
inline void NoBarrier_Store(volatile Atomic64* ptr, Atomic64 value) {
*ptr = value;
}
inline void Acquire_Store(volatile Atomic64 *ptr, Atomic64 value) {
*ptr = value;
MemoryBarrier();
}
inline void Release_Store(volatile Atomic64 *ptr, Atomic64 value) {
MemoryBarrier();
*ptr = value;
}
inline Atomic64 NoBarrier_Load(volatile const Atomic64* ptr) {
return *ptr;
}
inline Atomic64 Acquire_Load(volatile const Atomic64 *ptr) {
Atomic64 value = *ptr;
MemoryBarrier();
return value;
}
inline Atomic64 Release_Load(volatile const Atomic64 *ptr) {
MemoryBarrier();
return *ptr;
}
#endif // defined(__LP64__)
} // namespace base::subtle
} // namespace base
#endif // BASE_ATOMICOPS_INTERNALS_X86_MACOSX_H_
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