From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id 3997938582B9; Thu, 16 Jun 2022 02:31:00 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 3997938582B9 From: "crazylht at gmail dot com" To: gcc-bugs@gcc.gnu.org Subject: [Bug rtl-optimization/53533] [10/11/12/13 regression] vectorization causes loop unrolling test slowdown as measured by Adobe's C++Benchmark Date: Thu, 16 Jun 2022 02:31:00 +0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: rtl-optimization X-Bugzilla-Version: 4.7.1 X-Bugzilla-Keywords: missed-optimization X-Bugzilla-Severity: normal X-Bugzilla-Who: crazylht at gmail dot com X-Bugzilla-Status: NEW X-Bugzilla-Resolution: X-Bugzilla-Priority: P2 X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org X-Bugzilla-Target-Milestone: 10.4 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: Thu, 16 Jun 2022 02:31:00 -0000 https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D53533 --- Comment #50 from Hongtao.liu --- >=20 > On the RTL level likely simplify-rtx (or the variants used by combine) > only have limited support for vector operations. Instruction sequence window(more than 20 shift instructions) is too big for combine, hard to fix it in rtl.=