From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 22406 invoked by alias); 1 Aug 2012 18:43:57 -0000 Received: (qmail 22396 invoked by uid 22791); 1 Aug 2012 18:43:56 -0000 X-SWARE-Spam-Status: No, hits=-4.3 required=5.0 tests=ALL_TRUSTED,AWL,BAYES_00,KHOP_THREADED X-Spam-Check-By: sourceware.org Received: from localhost (HELO gcc.gnu.org) (127.0.0.1) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Wed, 01 Aug 2012 18:43:43 +0000 From: "wschmidt at gcc dot gnu.org" To: gcc-bugs@gcc.gnu.org Subject: [Bug tree-optimization/46556] Code size regression in struct access Date: Wed, 01 Aug 2012 18:43:00 -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-Keywords: missed-optimization X-Bugzilla-Severity: normal X-Bugzilla-Who: wschmidt at gcc dot gnu.org X-Bugzilla-Status: RESOLVED X-Bugzilla-Priority: P3 X-Bugzilla-Assigned-To: wschmidt at gcc dot gnu.org X-Bugzilla-Target-Milestone: 4.8.0 X-Bugzilla-Changed-Fields: Message-ID: In-Reply-To: References: X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/ Auto-Submitted: auto-generated Content-Type: text/plain; charset="UTF-8" MIME-Version: 1.0 Mailing-List: contact gcc-bugs-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Archive: List-Post: List-Help: Sender: gcc-bugs-owner@gcc.gnu.org X-SW-Source: 2012-08/txt/msg00068.txt.bz2 http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46556 --- Comment #12 from William J. Schmidt 2012-08-01 18:42:16 UTC --- (In reply to comment #11) > (In reply to comment #10) > > Fixed. > > Is it still your plan to also do something with the patch to expose target > addressing modes earlier? No, I'm afraid not. I spent more time than I like to remember investigating that possibility. My conclusion was that we lose too much structural aliasing information when we lower to MEM_REFs indiscriminately, resulting in unnecessary instruction scheduling constraints that harm performance. If this is to be done at some point in the future, there needs to be more infrastructure to allow the structural aliasing information to be retained throughout GIMPLE.