| // Copyright (c) 2012 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_MAC_H_ |
| #define BASE_ATOMICOPS_INTERNALS_MAC_H_ |
| |
| #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_MAC_H_ |