From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 13047 invoked by alias); 1 Jun 2007 23:13:32 -0000 Received: (qmail 12903 invoked by uid 48); 1 Jun 2007 23:13:20 -0000 Date: Fri, 01 Jun 2007 23:13:00 -0000 Message-ID: <20070601231320.12902.qmail@sourceware.org> X-Bugzilla-Reason: CC References: Subject: [Bug tree-optimization/32183] Gcc 4.3 revision 125030 miscompiles 482.sphinx3 in SPEC CPU 2006 In-Reply-To: Reply-To: gcc-bugzilla@gcc.gnu.org To: gcc-bugs@gcc.gnu.org From: "rakdver at gcc dot gnu dot org" 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: 2007-06/txt/msg00063.txt.bz2 ------- Comment #3 from rakdver at gcc dot gnu dot org 2007-06-01 23:13 ------- (In reply to comment #2) > Is that OK to transform > > float sf; > ... > sf = 500 * sf; > for (i = 0; i < ceplen; i++) > sum[i] *= sf; > > to > > for (i = 0; i < ceplen; i++) > sum[i] = (sum[i]* 500)*sf; > > You can certainly get the different results when sf is small and sum[i] is > large. with -ffast-math, this transformation is ok (although it does not seem to make sense to do it, it moves a multiplication into a loop). -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=32183