diff options
Diffstat (limited to 'src/atomic.h')
| -rw-r--r-- | src/atomic.h | 29 |
1 files changed, 29 insertions, 0 deletions
diff --git a/src/atomic.h b/src/atomic.h new file mode 100644 index 0000000..bcd8a47 --- /dev/null +++ b/src/atomic.h @@ -0,0 +1,29 @@ + +#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_feature(cxx_atomic) +#define ATOMIC_SWAP(addr, val)\ + __atomic_exchange(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_feature(cxx_atomic) +#define ATOMIC_LOAD(addr)\ + __atomic_load(addr, __ATOMIC_ACQUIRE) +#else +#define ATOMIC_LOAD(addr)\ + (__sync_synchronize(), *addr) +#endif |