From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 26180 invoked by alias); 29 Mar 2003 05:19:27 -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 26173 invoked from network); 29 Mar 2003 05:19:27 -0000 Received: from unknown (HELO Cantor.suse.de) (213.95.15.193) by sources.redhat.com with SMTP; 29 Mar 2003 05:19:27 -0000 Received: from Hermes.suse.de (Hermes.suse.de [213.95.15.136]) by Cantor.suse.de (Postfix) with ESMTP id A0FF414308; Sat, 29 Mar 2003 06:19:26 +0100 (MET) Received: from aj by arthur.inka.de with local (Exim 3.34 #1) id 18z8j3-0006OR-00; Sat, 29 Mar 2003 06:17:53 +0100 To: Casey Leedom Cc: Jan Hubicka , Joe Buck , dann@godzilla.ics.uci.edu, mark@codesourcery.com, gcc@gcc.gnu.org, dan@dberlin.org Subject: Re: SPEC2000 252.eon generates invalid results when compiled -O3 with g++ 3.3 From: Andreas Jaeger Date: Sat, 29 Mar 2003 09:49:00 -0000 In-Reply-To: <20030328214304.47039.qmail@web13104.mail.yahoo.com> (Casey Leedom's message of "Fri, 28 Mar 2003 13:43:04 -0800 (PST)") Message-ID: User-Agent: Gnus/5.090017 (Oort Gnus v0.17) XEmacs/21.4 (Artificial Intelligence, linux) References: <20030328214304.47039.qmail@web13104.mail.yahoo.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-SW-Source: 2003-03/txt/msg01743.txt.bz2 Casey Leedom writes: > / Date: Fri, 28 Mar 2003 02:21:56 +0100 > | From:"Jan Hubicka" > | > | > Okay, adding -fpmath=sse solved the problem. Interestingly enough adding > | > "-march=k8 -mcpu=k8" wasn't good enough. I would have thought that it > | > would have been from reading gcc/config/i386/i386.c:override_options() ... > | > | We've been chatting about this with glibc folks and they don't like the > | idea of losing the extra precisity 80bit temrporaries give, so > \ -mfpmath=sse can't be the default, unforutnately :( > > Okay, I understand that. So let me see if I'm 100% on the same page (I'm > very new to the x86 instruction set and it's history): > > 1. x87 is a stack-based floating point co-processor (originally on a separate > chip). It performs calulations in 80-bit arithmetic for "double"s? > > 2. SSE is a register-file floating point engine. It was designed to support > digital media applications and performs 64-bit arithmetic for "doubles"? > > 3. SSE2 is an update of SSE that extends the arithmetic to use 128-bit > (80-bit?) arithmetic for "doubles"? SSE and SSE2 together (don't remember what introduced what) have: - 32-bit floats and performs 32-bit float arithmetic for these - 64-bit doubles and performs 64-bit double arithmetic for these Andreas -- Andreas Jaeger SuSE Labs aj@suse.de private aj@arthur.inka.de http://www.suse.de/~aj