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Diffstat (limited to 'security/sandbox/chromium/base/atomicops.h')
| -rw-r--r-- | security/sandbox/chromium/base/atomicops.h | 161 |
1 files changed, 0 insertions, 161 deletions
diff --git a/security/sandbox/chromium/base/atomicops.h b/security/sandbox/chromium/base/atomicops.h deleted file mode 100644 index 3428fe87a..000000000 --- a/security/sandbox/chromium/base/atomicops.h +++ /dev/null @@ -1,161 +0,0 @@ -// 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. - -// For atomic operations on reference counts, see atomic_refcount.h. -// For atomic operations on sequence numbers, see atomic_sequence_num.h. - -// The routines exported by this module are subtle. If you use them, even if -// you get the code right, it will depend on careful reasoning about atomicity -// and memory ordering; it will be less readable, and harder to maintain. If -// you plan to use these routines, you should have a good reason, such as solid -// evidence that performance would otherwise suffer, or there being no -// alternative. You should assume only properties explicitly guaranteed by the -// specifications in this file. You are almost certainly _not_ writing code -// just for the x86; if you assume x86 semantics, x86 hardware bugs and -// implementations on other archtectures will cause your code to break. If you -// do not know what you are doing, avoid these routines, and use a Mutex. -// -// It is incorrect to make direct assignments to/from an atomic variable. -// You should use one of the Load or Store routines. The NoBarrier -// versions are provided when no barriers are needed: -// NoBarrier_Store() -// NoBarrier_Load() -// Although there are currently no compiler enforcement, you are encouraged -// to use these. -// - -#ifndef BASE_ATOMICOPS_H_ -#define BASE_ATOMICOPS_H_ - -#include <stdint.h> - -// Small C++ header which defines implementation specific macros used to -// identify the STL implementation. -// - libc++: captures __config for _LIBCPP_VERSION -// - libstdc++: captures bits/c++config.h for __GLIBCXX__ -#include <cstddef> - -#include "base/base_export.h" -#include "build/build_config.h" - -#if defined(OS_WIN) && 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 { - -typedef int32_t Atomic32; -#ifdef ARCH_CPU_64_BITS -// We need to be able to go between Atomic64 and AtomicWord implicitly. This -// means Atomic64 and AtomicWord should be the same type on 64-bit. -#if defined(__ILP32__) || defined(OS_NACL) -// NaCl's intptr_t is not actually 64-bits on 64-bit! -// http://code.google.com/p/nativeclient/issues/detail?id=1162 -typedef int64_t Atomic64; -#else -typedef intptr_t Atomic64; -#endif -#endif - -// Use AtomicWord for a machine-sized pointer. It will use the Atomic32 or -// Atomic64 routines below, depending on your architecture. -typedef intptr_t AtomicWord; - -// Atomically execute: -// result = *ptr; -// if (*ptr == old_value) -// *ptr = new_value; -// return result; -// -// I.e., replace "*ptr" with "new_value" if "*ptr" used to be "old_value". -// Always return the old value of "*ptr" -// -// This routine implies no memory barriers. -Atomic32 NoBarrier_CompareAndSwap(volatile Atomic32* ptr, - Atomic32 old_value, - Atomic32 new_value); - -// Atomically store new_value into *ptr, returning the previous value held in -// *ptr. This routine implies no memory barriers. -Atomic32 NoBarrier_AtomicExchange(volatile Atomic32* ptr, Atomic32 new_value); - -// Atomically increment *ptr by "increment". Returns the new value of -// *ptr with the increment applied. This routine implies no memory barriers. -Atomic32 NoBarrier_AtomicIncrement(volatile Atomic32* ptr, Atomic32 increment); - -Atomic32 Barrier_AtomicIncrement(volatile Atomic32* ptr, - Atomic32 increment); - -// These following lower-level operations are typically useful only to people -// implementing higher-level synchronization operations like spinlocks, -// mutexes, and condition-variables. They combine CompareAndSwap(), a load, or -// a store with appropriate memory-ordering instructions. "Acquire" operations -// ensure that no later memory access can be reordered ahead of the operation. -// "Release" operations ensure that no previous memory access can be reordered -// after the operation. "Barrier" operations have both "Acquire" and "Release" -// semantics. A MemoryBarrier() has "Barrier" semantics, but does no memory -// access. -Atomic32 Acquire_CompareAndSwap(volatile Atomic32* ptr, - Atomic32 old_value, - Atomic32 new_value); -Atomic32 Release_CompareAndSwap(volatile Atomic32* ptr, - Atomic32 old_value, - Atomic32 new_value); - -void MemoryBarrier(); -void NoBarrier_Store(volatile Atomic32* ptr, Atomic32 value); -void Acquire_Store(volatile Atomic32* ptr, Atomic32 value); -void Release_Store(volatile Atomic32* ptr, Atomic32 value); - -Atomic32 NoBarrier_Load(volatile const Atomic32* ptr); -Atomic32 Acquire_Load(volatile const Atomic32* ptr); -Atomic32 Release_Load(volatile const Atomic32* ptr); - -// 64-bit atomic operations (only available on 64-bit processors). -#ifdef ARCH_CPU_64_BITS -Atomic64 NoBarrier_CompareAndSwap(volatile Atomic64* ptr, - Atomic64 old_value, - Atomic64 new_value); -Atomic64 NoBarrier_AtomicExchange(volatile Atomic64* ptr, Atomic64 new_value); -Atomic64 NoBarrier_AtomicIncrement(volatile Atomic64* ptr, Atomic64 increment); -Atomic64 Barrier_AtomicIncrement(volatile Atomic64* ptr, Atomic64 increment); - -Atomic64 Acquire_CompareAndSwap(volatile Atomic64* ptr, - Atomic64 old_value, - Atomic64 new_value); -Atomic64 Release_CompareAndSwap(volatile Atomic64* ptr, - Atomic64 old_value, - Atomic64 new_value); -void NoBarrier_Store(volatile Atomic64* ptr, Atomic64 value); -void Acquire_Store(volatile Atomic64* ptr, Atomic64 value); -void Release_Store(volatile Atomic64* ptr, Atomic64 value); -Atomic64 NoBarrier_Load(volatile const Atomic64* ptr); -Atomic64 Acquire_Load(volatile const Atomic64* ptr); -Atomic64 Release_Load(volatile const Atomic64* ptr); -#endif // ARCH_CPU_64_BITS - -} // namespace subtle -} // namespace base - -#if defined(OS_WIN) -// TODO(jfb): The MSVC header includes windows.h, which other files end up -// relying on. Fix this as part of crbug.com/559247. -# include "base/atomicops_internals_x86_msvc.h" -#else -# include "base/atomicops_internals_portable.h" -#endif - -// On some platforms we need additional declarations to make -// AtomicWord compatible with our other Atomic* types. -#if defined(OS_MACOSX) || defined(OS_OPENBSD) -#include "base/atomicops_internals_atomicword_compat.h" -#endif - -#endif // BASE_ATOMICOPS_H_ |