--- atomic.h.orig	Fri May  9 15:35:52 2003
+++ atomic.h	Fri May  9 16:59:49 2003
@@ -73,18 +73,17 @@
   __sync_val_compare_and_swap_di ((long *) (mem), (long) (oldval), \
 				  (long) (newval))
 
-/* Atomically store newval and return the old value.  */
-#define atomic_exchange(mem, value) \
-  ({ __typeof (*mem) __result;						      \
-     if (sizeof (*mem) == 4)						      \
-       __result = __sync_lock_test_and_set_si ((int *) (mem), (int) (value)); \
-     else if (sizeof (*mem) == 8)					      \
-       __result = __sync_lock_test_and_set_di ((long *) (mem),		      \
-					       (long) (value));		      \
-     else								      \
-       abort ();							      \
-     __result; })
-       
+/* Atomically store newval and return the old value.  Acquire semantics. */
+#define atomic_exchange_acq(mem, value)  \
+  __sync_lock_test_and_set ((mem), (value))
+
+/* Atomically store newval and return the old value.  Acquire semantics. */
+#define atomic_exchange_full(mem, value) \
+  ( __sync_synchronize(), __sync_lock_test_and_set ((mem), (value)))	      \
+
+#define atomic_exchange_rel(mem, value) atomic_exchange_full(mem, value)
+
+#define atomic_exchange(mem, value) atomic_exchange_full(mem, value)
 
 #define atomic_exchange_and_add(mem, value) \
   ({ __typeof (*mem) __result;						      \