[PATCH 5/5] x86: Define atomic_compare_and_exchange_{val, bool}_acq using __atomic_compare_exchange_n
Uros Bizjak
ubizjak@gmail.com
Mon Sep 8 12:38:23 GMT 2025
No functional changes.
Signed-off-by: Uros Bizjak <ubizjak@gmail.com>
Cc: Florian Weimer <fweimer@redhat.com>
Cc: Adhemerval Zanella Netto <adhemerval.zanella@linaro.org>
Cc: Wilco Dijkstra <Wilco.Dijkstra@arm.com>
Cc: Collin Funk <collin.funk1@gmail.com>
Cc: H.J.Lu <hjl.tools@gmail.com>
Cc: Carlos O'Donell <carlos@redhat.com>
---
sysdeps/x86/atomic-machine.h | 18 ++++++++++++++----
1 file changed, 14 insertions(+), 4 deletions(-)
diff --git a/sysdeps/x86/atomic-machine.h b/sysdeps/x86/atomic-machine.h
index ebe8e978e5..d055364ddd 100644
--- a/sysdeps/x86/atomic-machine.h
+++ b/sysdeps/x86/atomic-machine.h
@@ -33,10 +33,20 @@
#define ATOMIC_EXCHANGE_USES_CAS 0
-#define atomic_compare_and_exchange_val_acq(mem, newval, oldval) \
- __sync_val_compare_and_swap (mem, oldval, newval)
-#define atomic_compare_and_exchange_bool_acq(mem, newval, oldval) \
- (! __sync_bool_compare_and_swap (mem, oldval, newval))
+#define atomic_compare_and_exchange_val_acq(mem, newval, oldval) \
+ ({ \
+ typeof (*mem) __oldval = (oldval); \
+ __atomic_compare_exchange_n (mem, (void *) &__oldval, newval, 0, \
+ __ATOMIC_ACQUIRE, __ATOMIC_RELAXED); \
+ __oldval; \
+ })
+
+#define atomic_compare_and_exchange_bool_acq(mem, newval, oldval) \
+ ({ \
+ typeof (*mem) __oldval = (oldval); \
+ !__atomic_compare_exchange_n (mem, (void *) &__oldval, newval, 0, \
+ __ATOMIC_ACQUIRE, __ATOMIC_RELAXED); \
+ })
#define atomic_exchange_acq(mem, newvalue) \
__atomic_exchange_n (mem, newvalue, __ATOMIC_ACQUIRE)
--
2.51.0
More information about the Libc-alpha
mailing list