From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id 69699384C003; Tue, 6 Apr 2021 08:46:17 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 69699384C003 From: "rsandifo at gcc dot gnu.org" To: gcc-bugs@gcc.gnu.org Subject: [Bug tree-optimization/99873] [11 Regression] GCC no longer makes as much use of ST3 Date: Tue, 06 Apr 2021 08:46:17 +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: 11.0 X-Bugzilla-Keywords: missed-optimization X-Bugzilla-Severity: normal X-Bugzilla-Who: rsandifo at gcc dot gnu.org X-Bugzilla-Status: ASSIGNED X-Bugzilla-Resolution: X-Bugzilla-Priority: P3 X-Bugzilla-Assigned-To: rsandifo at gcc dot gnu.org X-Bugzilla-Target-Milestone: 11.0 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: Tue, 06 Apr 2021 08:46:17 -0000 https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D99873 --- Comment #3 from rsandifo at gcc dot gnu.org --- (In reply to Richard Biener from comment #2) > We can also undo the splitting if SLP doesn't work out (keep the original > DR analysis chaining somewhere). Yeah, that sounds like something we should do for the cases that can't use store-lanes. So far though, I've not seen any cases that are better with the split group than with the store-lanes version, so I think we want the skip even if SLP would succeed.=