From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 627 invoked by alias); 4 Nov 2010 16:36:22 -0000 Received: (qmail 553 invoked by uid 22791); 4 Nov 2010 16:36:21 -0000 X-SWARE-Spam-Status: No, hits=-2.8 required=5.0 tests=ALL_TRUSTED,AWL,BAYES_00 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; Thu, 04 Nov 2010 16:36:15 +0000 From: "rguenth at gcc dot gnu.org" To: gcc-bugs@gcc.gnu.org Subject: [Bug rtl-optimization/45652] [4.6 Regression] gcc.dg/compat/scalar-by-value-3 FAILs with -O2 -fselective-scheduling2 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: rtl-optimization X-Bugzilla-Keywords: alias X-Bugzilla-Severity: normal X-Bugzilla-Who: rguenth at gcc dot gnu.org X-Bugzilla-Status: NEW X-Bugzilla-Priority: P1 X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org X-Bugzilla-Target-Milestone: 4.6.0 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 Date: Thu, 04 Nov 2010 16:36:00 -0000 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: 2010-11/txt/msg00555.txt.bz2 http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45652 --- Comment #3 from Richard Guenther 2010-11-04 16:35:55 UTC --- It looks like scheduling itself adds the instruction that references (mem/s:DI (reg:DI 4 si) [0 MEM[(struct S * {ref-all})addr.0_2]+0 S8 A64]) making use of 'si' where it was formerly not used but fails to record its set and thus invalidate the base alias info. Thus, register renaming needs to properly fixup alias info or refrain from touching registers which have reg_base_value set.