Hi!
Sorry, the last patch only partially fixed the __sync_* ICEs with
_BitInt(128) on ia32.
Even for !fetch we need to error out and return 0. I was afraid of
APIs like __atomic_exchange/__atomic_compare_exchange, those obviously
need to be supported even on _BitInt(128) on ia32, but they actually never
sync_resolve_size, they are handled by adding the size argument and using
the library version much earlier.
For fetch && !orig_format (i.e. __atomic_fetch_* etc.) we need to return -1
so that we handle it with a manualy __atomic_load +
__atomic_compare_exchange loop in the caller, all other cases should
be rejected.
Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?
2024-11-22 Jakub Jelinek <ja...@redhat.com>
PR c/117641
* c-common.cc (sync_resolve_size): For size 16 with _BitInt
on targets where TImode isn't supported, use goto incompatible if
!fetch.
* gcc.dg/bitint-117.c: New test.
--- gcc/c-family/c-common.cc.jj 2024-11-19 20:35:53.222455518 +0100
+++ gcc/c-family/c-common.cc 2024-11-21 11:23:07.897995741 +0100
@@ -7457,11 +7457,10 @@ sync_resolve_size (tree function, vec<tr
size = tree_to_uhwi (TYPE_SIZE_UNIT (type));
if (size == 16
- && fetch
&& TREE_CODE (type) == BITINT_TYPE
&& !targetm.scalar_mode_supported_p (TImode))
{
- if (!orig_format)
+ if (fetch && !orig_format)
return -1;
goto incompatible;
}
--- gcc/testsuite/gcc.dg/bitint-117.c.jj 2024-11-21 11:23:59.720260255
+0100
+++ gcc/testsuite/gcc.dg/bitint-117.c 2024-11-21 11:24:59.141416996 +0100
@@ -0,0 +1,13 @@
+/* PR c/117641 */
+/* { dg-do compile { target bitint575 } } */
+/* { dg-options "-std=c23" } */
+
+void
+foo (_BitInt(128) *b)
+{
+ __sync_add_and_fetch (b, 1); /* { dg-error "incompatible" ""
{ target { ! int128 } } } */
+ __sync_val_compare_and_swap (b, 0, 1); /* { dg-error "incompatible" ""
{ target { ! int128 } } } */
+ __sync_bool_compare_and_swap (b, 0, 1); /* { dg-error "incompatible" ""
{ target { ! int128 } } } */
+ __sync_lock_test_and_set (b, 1); /* { dg-error "incompatible" ""
{ target { ! int128 } } } */
+ __sync_lock_release (b); /* { dg-error "incompatible" ""
{ target { ! int128 } } } */
+}
Jakub
