diff options
Diffstat (limited to 'src/google/protobuf/stubs/atomicops_internals_pnacl.h')
-rw-r--r-- | src/google/protobuf/stubs/atomicops_internals_pnacl.h | 176 |
1 files changed, 167 insertions, 9 deletions
diff --git a/src/google/protobuf/stubs/atomicops_internals_pnacl.h b/src/google/protobuf/stubs/atomicops_internals_pnacl.h index b10ac02c..3b314fd0 100644 --- a/src/google/protobuf/stubs/atomicops_internals_pnacl.h +++ b/src/google/protobuf/stubs/atomicops_internals_pnacl.h @@ -33,39 +33,197 @@ #ifndef GOOGLE_PROTOBUF_ATOMICOPS_INTERNALS_PNACL_H_ #define GOOGLE_PROTOBUF_ATOMICOPS_INTERNALS_PNACL_H_ +#include <atomic> + namespace google { namespace protobuf { namespace internal { +// This implementation is transitional and maintains the original API for +// atomicops.h. This requires casting memory locations to the atomic types, and +// assumes that the API and the C++11 implementation are layout-compatible, +// which isn't true for all implementations or hardware platforms. The static +// assertion should detect this issue, were it to fire then this header +// shouldn't be used. +// +// TODO(jfb) If this header manages to stay committed then the API should be +// modified, and all call sites updated. +typedef volatile std::atomic<Atomic32>* AtomicLocation32; +static_assert(sizeof(*(AtomicLocation32) nullptr) == sizeof(Atomic32), + "incompatible 32-bit atomic layout"); + +inline void MemoryBarrier() { +#if defined(__GLIBCXX__) + // Work around libstdc++ bug 51038 where atomic_thread_fence was declared but + // not defined, leading to the linker complaining about undefined references. + __atomic_thread_fence(std::memory_order_seq_cst); +#else + std::atomic_thread_fence(std::memory_order_seq_cst); +#endif +} + inline Atomic32 NoBarrier_CompareAndSwap(volatile Atomic32* ptr, Atomic32 old_value, Atomic32 new_value) { - return __sync_val_compare_and_swap(ptr, old_value, new_value); + ((AtomicLocation32)ptr) + ->compare_exchange_strong(old_value, + new_value, + std::memory_order_relaxed, + std::memory_order_relaxed); + return old_value; } -inline void MemoryBarrier() { - __sync_synchronize(); +inline Atomic32 NoBarrier_AtomicExchange(volatile Atomic32* ptr, + Atomic32 new_value) { + return ((AtomicLocation32)ptr) + ->exchange(new_value, std::memory_order_relaxed); +} + +inline Atomic32 NoBarrier_AtomicIncrement(volatile Atomic32* ptr, + Atomic32 increment) { + return increment + + ((AtomicLocation32)ptr) + ->fetch_add(increment, std::memory_order_relaxed); +} + +inline Atomic32 Barrier_AtomicIncrement(volatile Atomic32* ptr, + Atomic32 increment) { + return increment + ((AtomicLocation32)ptr)->fetch_add(increment); } inline Atomic32 Acquire_CompareAndSwap(volatile Atomic32* ptr, Atomic32 old_value, Atomic32 new_value) { - Atomic32 ret = NoBarrier_CompareAndSwap(ptr, old_value, new_value); + ((AtomicLocation32)ptr) + ->compare_exchange_strong(old_value, + new_value, + std::memory_order_acquire, + std::memory_order_acquire); + return old_value; +} + +inline Atomic32 Release_CompareAndSwap(volatile Atomic32* ptr, + Atomic32 old_value, + Atomic32 new_value) { + ((AtomicLocation32)ptr) + ->compare_exchange_strong(old_value, + new_value, + std::memory_order_release, + std::memory_order_relaxed); + return old_value; +} + +inline void NoBarrier_Store(volatile Atomic32* ptr, Atomic32 value) { + ((AtomicLocation32)ptr)->store(value, std::memory_order_relaxed); +} + +inline void Acquire_Store(volatile Atomic32* ptr, Atomic32 value) { + ((AtomicLocation32)ptr)->store(value, std::memory_order_relaxed); MemoryBarrier(); - return ret; } inline void Release_Store(volatile Atomic32* ptr, Atomic32 value) { - MemoryBarrier(); - *ptr = value; + ((AtomicLocation32)ptr)->store(value, std::memory_order_release); +} + +inline Atomic32 NoBarrier_Load(volatile const Atomic32* ptr) { + return ((AtomicLocation32)ptr)->load(std::memory_order_relaxed); } inline Atomic32 Acquire_Load(volatile const Atomic32* ptr) { - Atomic32 value = *ptr; + return ((AtomicLocation32)ptr)->load(std::memory_order_acquire); +} + +inline Atomic32 Release_Load(volatile const Atomic32* ptr) { + MemoryBarrier(); + return ((AtomicLocation32)ptr)->load(std::memory_order_relaxed); +} + +#if defined(GOOGLE_PROTOBUF_ARCH_64_BIT) + +typedef volatile std::atomic<Atomic64>* AtomicLocation64; +static_assert(sizeof(*(AtomicLocation64) nullptr) == sizeof(Atomic64), + "incompatible 64-bit atomic layout"); + +inline Atomic64 NoBarrier_CompareAndSwap(volatile Atomic64* ptr, + Atomic64 old_value, + Atomic64 new_value) { + ((AtomicLocation64)ptr) + ->compare_exchange_strong(old_value, + new_value, + std::memory_order_relaxed, + std::memory_order_relaxed); + return old_value; +} + +inline Atomic64 NoBarrier_AtomicExchange(volatile Atomic64* ptr, + Atomic64 new_value) { + return ((AtomicLocation64)ptr) + ->exchange(new_value, std::memory_order_relaxed); +} + +inline Atomic64 NoBarrier_AtomicIncrement(volatile Atomic64* ptr, + Atomic64 increment) { + return increment + + ((AtomicLocation64)ptr) + ->fetch_add(increment, std::memory_order_relaxed); +} + +inline Atomic64 Barrier_AtomicIncrement(volatile Atomic64* ptr, + Atomic64 increment) { + return increment + ((AtomicLocation64)ptr)->fetch_add(increment); +} + +inline Atomic64 Acquire_CompareAndSwap(volatile Atomic64* ptr, + Atomic64 old_value, + Atomic64 new_value) { + ((AtomicLocation64)ptr) + ->compare_exchange_strong(old_value, + new_value, + std::memory_order_acquire, + std::memory_order_acquire); + return old_value; +} + +inline Atomic64 Release_CompareAndSwap(volatile Atomic64* ptr, + Atomic64 old_value, + Atomic64 new_value) { + ((AtomicLocation64)ptr) + ->compare_exchange_strong(old_value, + new_value, + std::memory_order_release, + std::memory_order_relaxed); + return old_value; +} + +inline void NoBarrier_Store(volatile Atomic64* ptr, Atomic64 value) { + ((AtomicLocation64)ptr)->store(value, std::memory_order_relaxed); +} + +inline void Acquire_Store(volatile Atomic64* ptr, Atomic64 value) { + ((AtomicLocation64)ptr)->store(value, std::memory_order_relaxed); MemoryBarrier(); - return value; } +inline void Release_Store(volatile Atomic64* ptr, Atomic64 value) { + ((AtomicLocation64)ptr)->store(value, std::memory_order_release); +} + +inline Atomic64 NoBarrier_Load(volatile const Atomic64* ptr) { + return ((AtomicLocation64)ptr)->load(std::memory_order_relaxed); +} + +inline Atomic64 Acquire_Load(volatile const Atomic64* ptr) { + return ((AtomicLocation64)ptr)->load(std::memory_order_acquire); +} + +inline Atomic64 Release_Load(volatile const Atomic64* ptr) { + MemoryBarrier(); + return ((AtomicLocation64)ptr)->load(std::memory_order_relaxed); +} + +#endif // defined(GOOGLE_PROTOBUF_ARCH_64_BIT) + } // namespace internal } // namespace protobuf } // namespace google |