On 26/06/2026 11:43, Jakub Jelinek wrote:
So, makes me wonder if it shouldn't be instead a compile test
(in addition to int128 effective target of course) whether
__atomic_compare_exchange_16 appears in the assembly or not.
Is it something like this that you have in mind?
diff --git gcc/testsuite/lib/target-supports.exp
gcc/testsuite/lib/target-supports.exp
index ae3af5893cc..394580ed871 100644
--- gcc/testsuite/lib/target-supports.exp
+++ gcc/testsuite/lib/target-supports.exp
@@ -10364,7 +10364,15 @@ proc check_effective_target_section_anchors { } {
# Return 1 if the target supports atomic operations on "int_128" values.
proc check_effective_target_sync_int_128 { } {
- return 0
+ return [check_no_messages_and_pattern sync_int_128 \
+ "__atomic_compare_exchange_16" assembly {
+ __int128 v;
+ void foo (__int128 *expected, __int128 desired)
+ {
+ __atomic_compare_exchange_n (&v, expected, desired, 0,
+ __ATOMIC_SEQ_CST, __ATOMIC_SEQ_CST);
+ }
+ } ""]
}
--
PA
