From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id 1193F385382C; Sat, 21 Aug 2021 03:17:26 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 1193F385382C From: "pinskia at gcc dot gnu.org" To: gcc-bugs@gcc.gnu.org Subject: [Bug rtl-optimization/101995] [9/10/11/12 Regression] regression built-in memset missed-optimization arm -Os Date: Sat, 21 Aug 2021 03:17:26 +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: 10.3.1 X-Bugzilla-Keywords: missed-optimization, needs-bisection, ra X-Bugzilla-Severity: normal X-Bugzilla-Who: pinskia 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: 9.5 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: Sat, 21 Aug 2021 03:17:27 -0000 https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D101995 --- Comment #3 from Andrew Pinski --- REG_RETURNED is no longer there. Looks like there is an extra move which caused the code to be different. For aarch64 we have: (insn 18 4 2 2 (set (reg:DI 94) (reg:DI 0 x0 [ foo ])) "/app/example.cpp":17:42 47 {*movdi_aarch64} (nil)) (insn 2 18 3 2 (set (reg/v/f:DI 90 [ foo ]) (reg:DI 94)) "/app/example.cpp":17:42 47 {*movdi_aarch64} (expr_list:REG_DEAD (reg:DI 94) (nil))) Before the call to memset.=