haiku/headers/libs/libcxxrt/atomic.h
Jonathan Schleifer f2c0917eea
Import libcxxrt
2015-11-09 18:01:58 +01:00

31 lines
784 B
C

#ifndef __has_builtin
#define __has_builtin(x) 0
#endif
#ifndef __has_feature
#define __has_feature(x) 0
#endif
/**
* Swap macro that enforces a happens-before relationship with a corresponding
* ATOMIC_LOAD.
*/
#if __has_builtin(__c11_atomic_exchange)
#define ATOMIC_SWAP(addr, val)\
__c11_atomic_exchange(reinterpret_cast<_Atomic(__typeof__(val))*>(addr), val, __ATOMIC_ACQ_REL)
#elif __has_builtin(__sync_swap)
#define ATOMIC_SWAP(addr, val)\
__sync_swap(addr, val)
#else
#define ATOMIC_SWAP(addr, val)\
__sync_lock_test_and_set(addr, val)
#endif
#if __has_builtin(__c11_atomic_load)
#define ATOMIC_LOAD(addr)\
__c11_atomic_load(reinterpret_cast<_Atomic(__typeof__(*addr))*>(addr), __ATOMIC_ACQUIRE)
#else
#define ATOMIC_LOAD(addr)\
(__sync_synchronize(), *addr)
#endif