https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112639
--- Comment #2 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Jakub Jelinek <ja...@gcc.gnu.org>: https://gcc.gnu.org/g:8a8a6d60c670c5153c5109df5fe68deb6fcf466d commit r14-5638-g8a8a6d60c670c5153c5109df5fe68deb6fcf466d Author: Jakub Jelinek <ja...@redhat.com> Date: Tue Nov 21 09:32:37 2023 +0100 builtins: Fix fold_builtin_query clzg/ctzg side-effects handling [PR112639] As the testcase shows, I've missed one spot where initially the code thinks it could use 2 argument IFN_CLZ/IFN_CTZ form, but then verifies it can't because it doesn't have the right target value and turns it into the arg0 ? arg1 : .C[LT]Z (arg0) form. That form evaluates the argument twice though and so needs save_expr, which I've missed to call in that case. In other cases where it is known from the beginning that it will be needed (e.g. the __builtin_clzg case on types smaller than unsigned int where we'll need to add an addend to the clz value) or the unsigned __int128 expansion called save_expr before. 2023-11-21 Jakub Jelinek <ja...@redhat.com> PR middle-end/112639 * builtins.cc (fold_builtin_bit_query): If arg0 has side-effects, arg1 is specified but cleared, call save_expr on arg0. * gcc.dg/torture/pr112639.c: New test.
