From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 14186 invoked by alias); 15 Aug 2011 09:07:32 -0000 Received: (qmail 14172 invoked by uid 22791); 15 Aug 2011 09:07:31 -0000 X-SWARE-Spam-Status: No, hits=-2.9 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; Mon, 15 Aug 2011 09:07:18 +0000 From: "enkovich.gnu at gmail dot com" To: gcc-bugs@gcc.gnu.org Subject: [Bug rtl-optimization/50037] Unroll factor exceeds max trip count Date: Mon, 15 Aug 2011 09:12:00 -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-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: enkovich.gnu at gmail dot com X-Bugzilla-Status: NEW X-Bugzilla-Priority: P3 X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org X-Bugzilla-Target-Milestone: --- 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: 2011-08/txt/msg01320.txt.bz2 http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50037 --- Comment #8 from Ilya Enkovich 2011-08-15 09:06:18 UTC --- This patch did not work for me. Tried on following loop (-O2 -funroll-loops): for ( count = ((*(hdrptr)) & 0x7); count > 0; count--, addr++ ) sum += *addr; No multiplication by 2 but still have the same unroll. I also was hoping this patch would prevent unroll of prologue loop generated by vectorizer.It uses '& 7' expression for iterations computation but this loop also uses MIN expression to limit number of iteration and is still unrolled.