atomicops_internals_atomicword_compat.h revision ddb351dbec246cf1fab5ec20d2d5520909041de1 
1// Copyright (c) 2011 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5// This file is an internal atomic implementation, use base/atomicops.h instead.
6
7#ifndef BASE_ATOMICOPS_INTERNALS_ATOMICWORD_COMPAT_H_
8#define BASE_ATOMICOPS_INTERNALS_ATOMICWORD_COMPAT_H_
9#pragma once
10
11// AtomicWord is a synonym for intptr_t, and Atomic32 is a synonym for int32,
12// which in turn means int. On some LP32 platforms, intptr_t is an int, but
13// on others, it's a long. When AtomicWord and Atomic32 are based on different
14// fundamental types, their pointers are incompatible.
15//
16// This file defines function overloads to allow both AtomicWord and Atomic32
17// data to be used with this interface.
18//
19// On LP64 platforms, AtomicWord and Atomic64 are both always long,
20// so this problem doesn't occur.
21
22#if !defined(ARCH_CPU_64_BITS)
23
24namespace base {
25namespace subtle {
26
27inline AtomicWord NoBarrier_CompareAndSwap(volatile AtomicWord* ptr,
28                                           AtomicWord old_value,
29                                           AtomicWord new_value) {
30  return NoBarrier_CompareAndSwap(
31      reinterpret_cast<volatile Atomic32*>(ptr), old_value, new_value);
32}
33
34inline AtomicWord NoBarrier_AtomicExchange(volatile AtomicWord* ptr,
35                                           AtomicWord new_value) {
36  return NoBarrier_AtomicExchange(
37      reinterpret_cast<volatile Atomic32*>(ptr), new_value);
38}
39
40inline AtomicWord NoBarrier_AtomicIncrement(volatile AtomicWord* ptr,
41                                            AtomicWord increment) {
42  return NoBarrier_AtomicIncrement(
43      reinterpret_cast<volatile Atomic32*>(ptr), increment);
44}
45
46inline AtomicWord Barrier_AtomicIncrement(volatile AtomicWord* ptr,
47                                          AtomicWord increment) {
48  return Barrier_AtomicIncrement(
49      reinterpret_cast<volatile Atomic32*>(ptr), increment);
50}
51
52inline AtomicWord Acquire_CompareAndSwap(volatile AtomicWord* ptr,
53                                         AtomicWord old_value,
54                                         AtomicWord new_value) {
55  return base::subtle::Acquire_CompareAndSwap(
56      reinterpret_cast<volatile Atomic32*>(ptr), old_value, new_value);
57}
58
59inline AtomicWord Release_CompareAndSwap(volatile AtomicWord* ptr,
60                                         AtomicWord old_value,
61                                         AtomicWord new_value) {
62  return base::subtle::Release_CompareAndSwap(
63      reinterpret_cast<volatile Atomic32*>(ptr), old_value, new_value);
64}
65
66inline void NoBarrier_Store(volatile AtomicWord *ptr, AtomicWord value) {
67  NoBarrier_Store(
68      reinterpret_cast<volatile Atomic32*>(ptr), value);
69}
70
71inline void Acquire_Store(volatile AtomicWord* ptr, AtomicWord value) {
72  return base::subtle::Acquire_Store(
73      reinterpret_cast<volatile Atomic32*>(ptr), value);
74}
75
76inline void Release_Store(volatile AtomicWord* ptr, AtomicWord value) {
77  return base::subtle::Release_Store(
78      reinterpret_cast<volatile Atomic32*>(ptr), value);
79}
80
81inline AtomicWord NoBarrier_Load(volatile const AtomicWord *ptr) {
82  return NoBarrier_Load(
83      reinterpret_cast<volatile const Atomic32*>(ptr));
84}
85
86inline AtomicWord Acquire_Load(volatile const AtomicWord* ptr) {
87  return base::subtle::Acquire_Load(
88      reinterpret_cast<volatile const Atomic32*>(ptr));
89}
90
91inline AtomicWord Release_Load(volatile const AtomicWord* ptr) {
92  return base::subtle::Release_Load(
93      reinterpret_cast<volatile const Atomic32*>(ptr));
94}
95
96}   // namespace base::subtle
97}   // namespace base
98
99#endif  // !defined(ARCH_CPU_64_BITS)
100
101#endif  // BASE_ATOMICOPS_INTERNALS_ATOMICWORD_COMPAT_H_
102