Use C++11 atomics

base/atomicops_internals_x86_msvc.h

-// Copyright (c) 2006-2008 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_MSVC_H_
-#define BASE_ATOMICOPS_INTERNALS_X86_MSVC_H_
-
-#include <windows.h>
-
-#include <intrin.h>
-
-#include "base/macros.h"
-
-#if defined(ARCH_CPU_64_BITS)
-// windows.h #defines this (only on x64). This causes problems because the
-// public API also uses MemoryBarrier at the public name for this fence. So, on
-// X64, undef it, and call its documented
-// (http://msdn.microsoft.com/en-us/library/windows/desktop/ms684208.aspx)
-// implementation directly.
-#undef MemoryBarrier
-#endif
-
-namespace base {
-namespace subtle {
-
-inline Atomic32 NoBarrier_CompareAndSwap(volatile Atomic32* ptr,
-                                         Atomic32 old_value,
-                                         Atomic32 new_value) {
-  LONG result = _InterlockedCompareExchange(
-      reinterpret_cast<volatile LONG*>(ptr),
-      static_cast<LONG>(new_value),
-      static_cast<LONG>(old_value));
-  return static_cast<Atomic32>(result);
-}
-
-inline Atomic32 NoBarrier_AtomicExchange(volatile Atomic32* ptr,
-                                         Atomic32 new_value) {
-  LONG result = _InterlockedExchange(
-      reinterpret_cast<volatile LONG*>(ptr),
-      static_cast<LONG>(new_value));
-  return static_cast<Atomic32>(result);
-}
-
-inline Atomic32 Barrier_AtomicIncrement(volatile Atomic32* ptr,
-                                        Atomic32 increment) {
-  return _InterlockedExchangeAdd(
-      reinterpret_cast<volatile LONG*>(ptr),
-      static_cast<LONG>(increment)) + increment;
-}
-
-inline Atomic32 NoBarrier_AtomicIncrement(volatile Atomic32* ptr,
-                                          Atomic32 increment) {
-  return Barrier_AtomicIncrement(ptr, increment);
-}
-
-#if !(defined(_MSC_VER) && _MSC_VER >= 1400)
-#error "We require at least vs2005 for MemoryBarrier"
-#endif
-inline void MemoryBarrier() {
-#if defined(ARCH_CPU_64_BITS)
-  // See #undef and note at the top of this file.
-  __faststorefence();
-#else
-  // We use MemoryBarrier from WinNT.h
-  ::MemoryBarrier();
-#endif
-}
-
-inline Atomic32 Acquire_CompareAndSwap(volatile Atomic32* ptr,
-                                       Atomic32 old_value,
-                                       Atomic32 new_value) {
-  return NoBarrier_CompareAndSwap(ptr, old_value, new_value);
-}
-
-inline Atomic32 Release_CompareAndSwap(volatile Atomic32* ptr,
-                                       Atomic32 old_value,
-                                       Atomic32 new_value) {
-  return NoBarrier_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) {
-  NoBarrier_AtomicExchange(ptr, value);
-              // acts as a barrier in this implementation
-}
-
-inline void Release_Store(volatile Atomic32* ptr, Atomic32 value) {
-  *ptr = value; // works w/o barrier for current Intel chips as of June 2005
-  // See comments in Atomic64 version of Release_Store() below.
-}
-
-inline Atomic32 NoBarrier_Load(volatile const Atomic32* ptr) {
-  return *ptr;
-}
-
-inline Atomic32 Acquire_Load(volatile const Atomic32* ptr) {
-  Atomic32 value = *ptr;
-  return value;
-}
-
-inline Atomic32 Release_Load(volatile const Atomic32* ptr) {
-  MemoryBarrier();
-  return *ptr;
-}
-
-#if defined(_WIN64)
-
-// 64-bit low-level operations on 64-bit platform.
-
-COMPILE_ASSERT(sizeof(Atomic64) == sizeof(PVOID), atomic_word_is_atomic);
-
-inline Atomic64 NoBarrier_CompareAndSwap(volatile Atomic64* ptr,
-                                         Atomic64 old_value,
-                                         Atomic64 new_value) {
-  PVOID result = InterlockedCompareExchangePointer(
-    reinterpret_cast<volatile PVOID*>(ptr),
-    reinterpret_cast<PVOID>(new_value), reinterpret_cast<PVOID>(old_value));
-  return reinterpret_cast<Atomic64>(result);
-}
-
-inline Atomic64 NoBarrier_AtomicExchange(volatile Atomic64* ptr,
-                                         Atomic64 new_value) {
-  PVOID result = InterlockedExchangePointer(
-    reinterpret_cast<volatile PVOID*>(ptr),
-    reinterpret_cast<PVOID>(new_value));
-  return reinterpret_cast<Atomic64>(result);
-}
-
-inline Atomic64 Barrier_AtomicIncrement(volatile Atomic64* ptr,
-                                        Atomic64 increment) {
-  return InterlockedExchangeAdd64(
-      reinterpret_cast<volatile LONGLONG*>(ptr),
-      static_cast<LONGLONG>(increment)) + increment;
-}
-
-inline Atomic64 NoBarrier_AtomicIncrement(volatile Atomic64* ptr,
-                                          Atomic64 increment) {
-  return Barrier_AtomicIncrement(ptr, increment);
-}
-
-inline void NoBarrier_Store(volatile Atomic64* ptr, Atomic64 value) {
-  *ptr = value;
-}
-
-inline void Acquire_Store(volatile Atomic64* ptr, Atomic64 value) {
-  NoBarrier_AtomicExchange(ptr, value);
-              // acts as a barrier in this implementation
-}
-
-inline void Release_Store(volatile Atomic64* ptr, Atomic64 value) {
-  *ptr = value; // works w/o barrier for current Intel chips as of June 2005
-
-  // When new chips come out, check:
-  //  IA-32 Intel Architecture Software Developer's Manual, Volume 3:
-  //  System Programming Guide, Chatper 7: Multiple-processor management,
-  //  Section 7.2, Memory Ordering.
-  // Last seen at:
-  //   http://developer.intel.com/design/pentium4/manuals/index_new.htm
-}
-
-inline Atomic64 NoBarrier_Load(volatile const Atomic64* ptr) {
-  return *ptr;
-}
-
-inline Atomic64 Acquire_Load(volatile const Atomic64* ptr) {
-  Atomic64 value = *ptr;
-  return value;
-}
-
-inline Atomic64 Release_Load(volatile const Atomic64* ptr) {
-  MemoryBarrier();
-  return *ptr;
-}
-
-inline Atomic64 Acquire_CompareAndSwap(volatile Atomic64* ptr,
-                                       Atomic64 old_value,
-                                       Atomic64 new_value) {
-  return NoBarrier_CompareAndSwap(ptr, old_value, new_value);
-}
-
-inline Atomic64 Release_CompareAndSwap(volatile Atomic64* ptr,
-                                       Atomic64 old_value,
-                                       Atomic64 new_value) {
-  return NoBarrier_CompareAndSwap(ptr, old_value, new_value);
-}
-
-
-#endif  // defined(_WIN64)
-
-}  // namespace base::subtle
-}  // namespace base
-
-#endif  // BASE_ATOMICOPS_INTERNALS_X86_MSVC_H_