| Index: src/atomicops.h
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| diff --git a/src/atomicops.h b/src/atomicops.h
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| new file mode 100644
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| index 0000000000000000000000000000000000000000..72a0d0fb5a3484b214580ab1a56d91be62fa15d8
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| +++ b/src/atomicops.h
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| @@ -0,0 +1,165 @@
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| +// Copyright 2010 the V8 project authors. All rights reserved.
|
| +// Redistribution and use in source and binary forms, with or without
|
| +// modification, are permitted provided that the following conditions are
|
| +// met:
|
| +//
|
| +// * Redistributions of source code must retain the above copyright
|
| +// notice, this list of conditions and the following disclaimer.
|
| +// * Redistributions in binary form must reproduce the above
|
| +// copyright notice, this list of conditions and the following
|
| +// disclaimer in the documentation and/or other materials provided
|
| +// with the distribution.
|
| +// * Neither the name of Google Inc. nor the names of its
|
| +// contributors may be used to endorse or promote products derived
|
| +// from this software without specific prior written permission.
|
| +//
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| +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
|
| +// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
|
| +// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
|
| +// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
|
| +// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
|
| +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
|
| +// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
|
| +// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
|
| +// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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| +// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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| +// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
| +
|
| +// 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
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| +// and memory ordering; it will be less readable, and harder to maintain. If
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| +// 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
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| +// alternative. You should assume only properties explicitly guaranteed by the
|
| +// specifications in this file. You are almost certainly _not_ writing code
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| +// just for the x86; if you assume x86 semantics, x86 hardware bugs and
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| +// implementations on other archtectures will cause your code to break. If you
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| +// 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.
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| +// You should use one of the Load or Store routines. The NoBarrier
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| +// versions are provided when no barriers are needed:
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| +// NoBarrier_Store()
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| +// NoBarrier_Load()
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| +// Although there are currently no compiler enforcement, you are encouraged
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| +// to use these.
|
| +//
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| +
|
| +#ifndef V8_ATOMICOPS_H_
|
| +#define V8_ATOMICOPS_H_
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| +
|
| +#include "../include/v8.h"
|
| +#include "globals.h"
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| +
|
| +namespace v8 {
|
| +namespace internal {
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| +
|
| +typedef int32_t Atomic32;
|
| +#ifdef V8_HOST_ARCH_64_BIT
|
| +// We need to be able to go between Atomic64 and AtomicWord implicitly. This
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| +// means Atomic64 and AtomicWord should be the same type on 64-bit.
|
| +#if defined(__APPLE__)
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| +// MacOS is an exception to the implicit conversion rule above,
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| +// because it uses long for intptr_t.
|
| +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;
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| +
|
| +// Atomically execute:
|
| +// result = *ptr;
|
| +// if (*ptr == old_value)
|
| +// *ptr = new_value;
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| +// return result;
|
| +//
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| +// 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,
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| + Atomic32 old_value,
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| + 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);
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| +
|
| +// 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);
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| +
|
| +Atomic32 Barrier_AtomicIncrement(volatile Atomic32* ptr,
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| + Atomic32 increment);
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| +
|
| +// These following lower-level operations are typically useful only to people
|
| +// implementing higher-level synchronization operations like spinlocks,
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| +// mutexes, and condition-variables. They combine CompareAndSwap(), a load, or
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| +// 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
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| +// 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,
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| + 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 V8_HOST_ARCH_64_BIT
|
| +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 // V8_HOST_ARCH_64_BIT
|
| +
|
| +} } // namespace v8::internal
|
| +
|
| +// Include our platform specific implementation.
|
| +#if defined(_MSC_VER) && \
|
| + (defined(V8_HOST_ARCH_IA32) || defined(V8_HOST_ARCH_X64))
|
| +#include "atomicops_internals_x86_msvc.h"
|
| +#elif defined(__APPLE__) && \
|
| + (defined(V8_HOST_ARCH_IA32) || defined(V8_HOST_ARCH_X64))
|
| +#include "atomicops_internals_x86_macosx.h"
|
| +#elif defined(__GNUC__) && \
|
| + (defined(V8_HOST_ARCH_IA32) || defined(V8_HOST_ARCH_X64))
|
| +#include "atomicops_internals_x86_gcc.h"
|
| +#elif defined(__GNUC__) && defined(V8_HOST_ARCH_ARM)
|
| +#include "atomicops_internals_arm_gcc.h"
|
| +#else
|
| +#error "Atomic operations are not supported on your platform"
|
| +#endif
|
| +
|
| +#endif // V8_ATOMICOPS_H_
|
|
|