From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id 0A0C93858420; Sun, 28 Nov 2021 21:24:34 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 0A0C93858420 From: "aoliva at gcc dot gnu.org" To: gcc-bugs@gcc.gnu.org Subject: [Bug target/103302] wrong code with -fharden-compares Date: Sun, 28 Nov 2021 21:24:34 +0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: target X-Bugzilla-Version: 12.0 X-Bugzilla-Keywords: wrong-code X-Bugzilla-Severity: normal X-Bugzilla-Who: aoliva at gcc dot gnu.org X-Bugzilla-Status: ASSIGNED X-Bugzilla-Resolution: X-Bugzilla-Priority: P3 X-Bugzilla-Assigned-To: aoliva at gcc dot gnu.org X-Bugzilla-Target-Milestone: --- 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 X-BeenThere: gcc-bugs@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-bugs mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 28 Nov 2021 21:24:35 -0000 https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D103302 --- Comment #5 from Alexandre Oliva --- Hello, Jim, Thanks for the investigation, that's useful. I guess the register allocator shouldn't choose to coalesce registers when there's a clobber afterwards, o= r it should drop the clobber, since otherwise it clobbers the coalesced set. Anyway, I'm reworking the asm that prevents optimization because of bug 103= 149 and bug 103097, it might end up avoiding this unfortunate situation. We'll see...=