1 // Copyright (c) 2006-2008 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_X86_MSVC_H_ 8 #define BASE_ATOMICOPS_INTERNALS_X86_MSVC_H_ 9 #pragma once 10 11 #include <windows.h> 12 13 namespace base { 14 namespace subtle { 15 16 inline Atomic32 NoBarrier_CompareAndSwap(volatile Atomic32* ptr, 17 Atomic32 old_value, 18 Atomic32 new_value) { 19 LONG result = InterlockedCompareExchange( 20 reinterpret_cast<volatile LONG*>(ptr), 21 static_cast<LONG>(new_value), 22 static_cast<LONG>(old_value)); 23 return static_cast<Atomic32>(result); 24 } 25 26 inline Atomic32 NoBarrier_AtomicExchange(volatile Atomic32* ptr, 27 Atomic32 new_value) { 28 LONG result = InterlockedExchange( 29 reinterpret_cast<volatile LONG*>(ptr), 30 static_cast<LONG>(new_value)); 31 return static_cast<Atomic32>(result); 32 } 33 34 inline Atomic32 Barrier_AtomicIncrement(volatile Atomic32* ptr, 35 Atomic32 increment) { 36 return InterlockedExchangeAdd( 37 reinterpret_cast<volatile LONG*>(ptr), 38 static_cast<LONG>(increment)) + increment; 39 } 40 41 inline Atomic32 NoBarrier_AtomicIncrement(volatile Atomic32* ptr, 42 Atomic32 increment) { 43 return Barrier_AtomicIncrement(ptr, increment); 44 } 45 46 #if !(defined(_MSC_VER) && _MSC_VER >= 1400) 47 #error "We require at least vs2005 for MemoryBarrier" 48 #endif 49 inline void MemoryBarrier() { 50 // We use MemoryBarrier from WinNT.h 51 ::MemoryBarrier(); 52 } 53 54 inline Atomic32 Acquire_CompareAndSwap(volatile Atomic32* ptr, 55 Atomic32 old_value, 56 Atomic32 new_value) { 57 return NoBarrier_CompareAndSwap(ptr, old_value, new_value); 58 } 59 60 inline Atomic32 Release_CompareAndSwap(volatile Atomic32* ptr, 61 Atomic32 old_value, 62 Atomic32 new_value) { 63 return NoBarrier_CompareAndSwap(ptr, old_value, new_value); 64 } 65 66 inline void NoBarrier_Store(volatile Atomic32* ptr, Atomic32 value) { 67 *ptr = value; 68 } 69 70 inline void Acquire_Store(volatile Atomic32* ptr, Atomic32 value) { 71 NoBarrier_AtomicExchange(ptr, value); 72 // acts as a barrier in this implementation 73 } 74 75 inline void Release_Store(volatile Atomic32* ptr, Atomic32 value) { 76 *ptr = value; // works w/o barrier for current Intel chips as of June 2005 77 // See comments in Atomic64 version of Release_Store() below. 78 } 79 80 inline Atomic32 NoBarrier_Load(volatile const Atomic32* ptr) { 81 return *ptr; 82 } 83 84 inline Atomic32 Acquire_Load(volatile const Atomic32* ptr) { 85 Atomic32 value = *ptr; 86 return value; 87 } 88 89 inline Atomic32 Release_Load(volatile const Atomic32* ptr) { 90 MemoryBarrier(); 91 return *ptr; 92 } 93 94 #if defined(_WIN64) 95 96 // 64-bit low-level operations on 64-bit platform. 97 98 COMPILE_ASSERT(sizeof(Atomic64) == sizeof(PVOID), atomic_word_is_atomic); 99 100 inline Atomic64 NoBarrier_CompareAndSwap(volatile Atomic64* ptr, 101 Atomic64 old_value, 102 Atomic64 new_value) { 103 PVOID result = InterlockedCompareExchangePointer( 104 reinterpret_cast<volatile PVOID*>(ptr), 105 reinterpret_cast<PVOID>(new_value), reinterpret_cast<PVOID>(old_value)); 106 return reinterpret_cast<Atomic64>(result); 107 } 108 109 inline Atomic64 NoBarrier_AtomicExchange(volatile Atomic64* ptr, 110 Atomic64 new_value) { 111 PVOID result = InterlockedExchangePointer( 112 reinterpret_cast<volatile PVOID*>(ptr), 113 reinterpret_cast<PVOID>(new_value)); 114 return reinterpret_cast<Atomic64>(result); 115 } 116 117 inline Atomic64 Barrier_AtomicIncrement(volatile Atomic64* ptr, 118 Atomic64 increment) { 119 return InterlockedExchangeAdd64( 120 reinterpret_cast<volatile LONGLONG*>(ptr), 121 static_cast<LONGLONG>(increment)) + increment; 122 } 123 124 inline Atomic64 NoBarrier_AtomicIncrement(volatile Atomic64* ptr, 125 Atomic64 increment) { 126 return Barrier_AtomicIncrement(ptr, increment); 127 } 128 129 inline void NoBarrier_Store(volatile Atomic64* ptr, Atomic64 value) { 130 *ptr = value; 131 } 132 133 inline void Acquire_Store(volatile Atomic64* ptr, Atomic64 value) { 134 NoBarrier_AtomicExchange(ptr, value); 135 // acts as a barrier in this implementation 136 } 137 138 inline void Release_Store(volatile Atomic64* ptr, Atomic64 value) { 139 *ptr = value; // works w/o barrier for current Intel chips as of June 2005 140 141 // When new chips come out, check: 142 // IA-32 Intel Architecture Software Developer's Manual, Volume 3: 143 // System Programming Guide, Chatper 7: Multiple-processor management, 144 // Section 7.2, Memory Ordering. 145 // Last seen at: 146 // http://developer.intel.com/design/pentium4/manuals/index_new.htm 147 } 148 149 inline Atomic64 NoBarrier_Load(volatile const Atomic64* ptr) { 150 return *ptr; 151 } 152 153 inline Atomic64 Acquire_Load(volatile const Atomic64* ptr) { 154 Atomic64 value = *ptr; 155 return value; 156 } 157 158 inline Atomic64 Release_Load(volatile const Atomic64* ptr) { 159 MemoryBarrier(); 160 return *ptr; 161 } 162 163 inline Atomic64 Acquire_CompareAndSwap(volatile Atomic64* ptr, 164 Atomic64 old_value, 165 Atomic64 new_value) { 166 return NoBarrier_CompareAndSwap(ptr, old_value, new_value); 167 } 168 169 inline Atomic64 Release_CompareAndSwap(volatile Atomic64* ptr, 170 Atomic64 old_value, 171 Atomic64 new_value) { 172 return NoBarrier_CompareAndSwap(ptr, old_value, new_value); 173 } 174 175 176 #endif // defined(_WIN64) 177 178 } // namespace base::subtle 179 } // namespace base 180 181 #endif // BASE_ATOMICOPS_INTERNALS_X86_MSVC_H_ 182