From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 17061 invoked by alias); 29 Jun 2005 18:32:39 -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 17049 invoked by uid 22791); 29 Jun 2005 18:32:35 -0000 Received: from x93.infopact.nl (HELO x93.infopact.nl) (212.29.160.93) by sourceware.org (qpsmtpd/0.30-dev) with ESMTP; Wed, 29 Jun 2005 18:32:35 +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 j5TIWCDt003982; Wed, 29 Jun 2005 20:32:13 +0200 From: Steven Bosscher To: Daniel Berlin Subject: Re: Do C++ signed types have modulo semantics? Date: Wed, 29 Jun 2005 18:32:00 -0000 User-Agent: KMail/1.7.1 Cc: Ulrich Weigand , 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> <200506291846.34864.stevenb@suse.de> <1120068079.7612.31.camel@linux-009002219098.watson.ibm.com> In-Reply-To: <1120068079.7612.31.camel@linux-009002219098.watson.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200506292032.16423.stevenb@suse.de> X-Spam-Score: undef - spam-scanning disabled X-SW-Source: 2005-06/txt/msg01269.txt.bz2 On Wednesday 29 June 2005 20:01, Daniel Berlin wrote: > So i would advise anyone arguing against turning on -fwrapv simply > because it doesn't seem to hurt us at O2. wtf, "doesn't seem to hurt us at -O2". Look again at the 64 bits numbers! Losing 5% on the fp benchmarks is a serious regression. Even without exercising the heavy-ammo loop optimizers, -fwrapv is a serious performance-hurter. Gr. Steven