From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id D015D3858012; Wed, 31 Mar 2021 09:10:59 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org D015D3858012 From: "hubicka at ucw dot cz" To: gcc-bugs@gcc.gnu.org Subject: [Bug ipa/99835] missed optimization for dead code elimination at -O3 (vs. -O1) Date: Wed, 31 Mar 2021 09:10:59 +0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: ipa X-Bugzilla-Version: 11.0 X-Bugzilla-Keywords: missed-optimization X-Bugzilla-Severity: normal X-Bugzilla-Who: hubicka at ucw dot cz 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: --- 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: Wed, 31 Mar 2021 09:10:59 -0000 https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D99835 --- Comment #4 from Jan Hubicka --- > But inside a SCC the order is arbitrary anyway. Note I'd only re-order S= CCs > and keep the postordering the same otherwise. We compile leaf functions first to be able to propagated to their callers. In order to be able to optimize out functions in case call was optimized out, we would need to compile in reverse order than we do now... Honza=