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/*
* Copyright (C) 2008 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/*
* Atomic operations
*/
#ifndef DALVIK_ATOMIC_H_
#define DALVIK_ATOMIC_H_
#include <cutils/atomic.h> /* use common Android atomic ops */
#include <cutils/atomic-inline.h> /* and some uncommon ones */
/*
* NOTE: Two "quasiatomic" operations on the exact same memory address
* are guaranteed to operate atomically with respect to each other,
* but no guarantees are made about quasiatomic operations mixed with
* non-quasiatomic operations on the same address, nor about
* quasiatomic operations that are performed on partially-overlapping
* memory.
*
* Only the "Sync" versions of these provide a memory barrier.
*/
/*
* Swap the 64-bit value at "addr" with "value". Returns the previous
* value.
*/
extern "C" int64_t dvmQuasiAtomicSwap64(int64_t value, volatile int64_t* addr);
/*
* Swap the 64-bit value at "addr" with "value". Returns the previous
* value. Provides memory barriers.
*/
extern "C" int64_t dvmQuasiAtomicSwap64Sync(int64_t value,
volatile int64_t* addr);
/*
* Read the 64-bit value at "addr".
*/
extern "C" int64_t dvmQuasiAtomicRead64(volatile const int64_t* addr);
/*
* If the value at "addr" is equal to "oldvalue", replace it with "newvalue"
* and return 0. Otherwise, don't swap, and return nonzero.
*/
int dvmQuasiAtomicCas64(int64_t oldvalue, int64_t newvalue,
volatile int64_t* addr);
#endif // DALVIK_ATOMIC_H_