From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id AC8D63858D20; Fri, 2 Dec 2022 10:16:26 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org AC8D63858D20 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1669976186; bh=5XXb3k0Dnd8dNlgJUJry9AiBmjCNWNRARSPhwwaV8yk=; h=From:To:Subject:Date:In-Reply-To:References:From; b=kROxrSJA4fhiC3v6BsP5EhATKqdMiDk6Fc5jFhU2nW+SWApEqGZY/6rmCk7dY4IP1 keNeJVtg2P+6PHMW2PpxJpT606dhxKSgeA9FiIAvG6ISI+D5/FADTIEzfuWkoPLtEe ndq1PVG/OU/3KR9kOUiOc0rr0CrMyHd9GwONvO+A= From: "jakub at gcc dot gnu.org" To: gcc-bugs@gcc.gnu.org Subject: [Bug tree-optimization/107833] [12/13 Regression] wrong code at -Os and above on x86_64-linux-gnu since r12-5138-ge82c382971664d6f Date: Fri, 02 Dec 2022 10:16:25 +0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: tree-optimization X-Bugzilla-Version: 12.2.0 X-Bugzilla-Keywords: wrong-code X-Bugzilla-Severity: normal X-Bugzilla-Who: jakub at gcc dot gnu.org X-Bugzilla-Status: NEW X-Bugzilla-Resolution: X-Bugzilla-Priority: P3 X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org X-Bugzilla-Target-Milestone: 12.3 X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 List-Id: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D107833 --- Comment #12 from Jakub Jelinek --- So, do we whack-a-mole in this case some more and try harder in mark_ssa_maybe_undefs by basically repeating the CCP4 UNDEFINED propagation, or invent some new s= tmt or marking that IVOPTS could use before the loop to turn possibly undefined into undefined but always the same random pattern within the same invocation (kind of like asm ("" : "+g" (undef));), or something else (like after IVOP= TS stop the UNDEFINED propagation on loop header PHIs or something similar)?=