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/*
* Copyright 2014 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#ifndef SkBarriers_arm_DEFINED
#define SkBarriers_arm_DEFINED
static inline void sk_compiler_barrier() { asm volatile("" : : : "memory"); }
template <typename T>
T sk_acquire_load(T* ptr) {
T val = *ptr;
__sync_synchronize(); // Issue a full barrier, which is an overkill acquire barrier.
return val;
}
template <typename T>
T sk_consume_load(T* ptr) {
T val = *ptr;
// Unlike acquire, consume loads (data-dependent loads) are guaranteed not to reorder on ARM.
// No memory barrier is needed, so we just use a compiler barrier.
// C.f. http://preshing.com/20140709/the-purpose-of-memory_order_consume-in-cpp11/
sk_compiler_barrier();
return val;
}
template <typename T>
void sk_release_store(T* ptr, T val) {
__sync_synchronize(); // Issue a full barrier, which is an overkill release barrier.
*ptr = val;
}
#endif//SkBarriers_x86_DEFINED
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