-#define SYNC_SWAP __sync_lock_test_and_set
-#define SYNC_CAS __sync_val_compare_and_swap
-#define SYNC_ADD __sync_add_and_fetch
-#define SYNC_FETCH_AND_OR __sync_fetch_and_or
+#define SYNC_SWAP __sync_lock_test_and_set
+#define SYNC_CAS __sync_val_compare_and_swap
+#define SYNC_ADD __sync_add_and_fetch
+#define SYNC_FETCH_AND_OR __sync_fetch_and_or
+
+#define COUNT_TRAILING_ZEROS __builtin_ctz