From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 1000 invoked by alias); 28 Jun 2005 12:09:38 -0000 Mailing-List: contact gcc-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Archive: List-Post: List-Help: Sender: gcc-owner@gcc.gnu.org Received: (qmail 376 invoked by uid 22791); 28 Jun 2005 12:09:15 -0000 Received: from x93.infopact.nl (HELO x93.infopact.nl) (212.29.160.93) by sourceware.org (qpsmtpd/0.30-dev) with ESMTP; Tue, 28 Jun 2005 12:09:15 +0000 Received: from 63-66-dsl.ipact.nl (63-66-dsl.ipact.nl [84.35.66.63]) by x93.infopact.nl (8.12.10/8.12.10) with ESMTP id j5SC90R4017026; Tue, 28 Jun 2005 14:09:00 +0200 From: Steven Bosscher To: Ulrich Weigand Subject: Re: Do C++ signed types have modulo semantics? Date: Tue, 28 Jun 2005 12:09:00 -0000 User-Agent: KMail/1.7.1 Cc: gcc@gcc.gnu.org, Robert Dewar , Mark Mitchell , Michael Veksler , Paul Koning , gdr@integrable-solutions.net, nathan@codesourcery.com References: <200506281202.j5SC27s7024579@53v30g15.boeblingen.de.ibm.com> In-Reply-To: <200506281202.j5SC27s7024579@53v30g15.boeblingen.de.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200506281409.02246.stevenb@suse.de> X-Spam-Score: undef - spam-scanning disabled X-SW-Source: 2005-06/txt/msg01098.txt.bz2 On Tuesday 28 June 2005 14:02, Ulrich Weigand wrote: > Steven Bosscher wrote: > > Anyway, I've started a SPEC run with "-O2" vs. "-O2 -fwrapv". Let's see > > how big the damage would be ;-) > > Please make sure to include a 64-bit target, where it actually makes any > difference. (I recall performance degradations of 20-30% in some > SPECfp cases from getting induction variable reduction wrong ...) Yeah, I'm testing on an AMD64 box, both 64 bits and 32 bits. Gr. Steven