https://gcc.gnu.org/bugzilla/show_bug.cgi?id=126742
--- Comment #4 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Kael Andrew Franco <[email protected]>: https://gcc.gnu.org/g:0621cf67366ffa2215cdd081b1ca1c3c577e8b70 commit r17-3166-g0621cf67366ffa2215cdd081b1ca1c3c577e8b70 Author: Kael Andrew Alonzo Franco <[email protected]> Date: Sat Aug 8 22:04:12 2026 -0400 middle-end: Wrong code for a != b | (a|b) != 0. [PR126742] Since r17-2886, GCC does a wrong optimize with: (a == b) & ((a|b) == 0) -> ((a|b) != 0) (a != b) | ((a|b) != 0) -> ((a|b) == 0) Should be: (a == b) & ((a|b) == 0) -> ((a|b) == 0) (a != b) | ((a|b) != 0) -> ((a|b) != 0) Regtest missed this because gcc.dg/int-bwise-opt-2.c only test: /* { dg-final { scan-tree-dump-times "a == b" 0 "optimized" } } */ /* { dg-final { scan-tree-dump-times "a != b" 0 "optimized" } } */ Make this test more rigorous by comparing the final code. Bootstrapped and regtested on x86_64-pc-linux-gnu. PR middle-end/126742 gcc/ChangeLog: * match.pd: Fix wrong code. gcc/testsuite/ChangeLog: * gcc.dg/int-bwise-opt-2.c: Also test for PR126742. Signed-off-by: Kael Andrew Franco <[email protected]>
