From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 30659 invoked by alias); 29 Jan 2004 16:27:58 -0000 Mailing-List: contact gcc-bugs-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Archive: List-Post: List-Help: Sender: gcc-bugs-owner@gcc.gnu.org Received: (qmail 30647 invoked by alias); 29 Jan 2004 16:27:57 -0000 Date: Thu, 29 Jan 2004 16:27:00 -0000 Message-ID: <20040129162757.30646.qmail@sources.redhat.com> From: "william dot crocker at analog dot com" To: gcc-bugs@gcc.gnu.org In-Reply-To: <20040116211131.13712.william.crocker@analog.com> References: <20040116211131.13712.william.crocker@analog.com> Reply-To: gcc-bugzilla@gcc.gnu.org Subject: [Bug optimization/13712] Executable runs 25% slower than when compiled with INTEL compiler X-Bugzilla-Reason: CC X-SW-Source: 2004-01/txt/msg03769.txt.bz2 List-Id: ------- Additional Comments From william dot crocker at analog dot com 2004-01-29 16:27 ------- Subject: Re: Executable runs 25% slower than when compiled with INTEL compiler > > ------- Additional Comments From falk at debian dot org 2004-01-29 16:01 ------- > Thanks for the test case. I see it's using FP math heavily. Could you also > try the options -ffast-math and -mfpmath=sse? AFAIK the Intel compiler does > the equivalent of these switches by default so they are needed for a fair > comparison. > Your email suggest that I sould put something (?) after the sse, but the online GCC doc does not show this. I get this when compiling. >/home/whc/lintel/gcc/usr_local/bin/g++ -O3 -c -Wno-deprecated -ffast-math -mfpmath=sse y.cc cc1plus: warning: SSE instruction set disabled, using 387 arithmetics I also tried -msse and -msse2, but got no better than 30 Seconds. ANYWAY it runs and I get the following which now shows INTEL with only a 22% advantage versus the previous 37%. Bill ###### USING GCC ###### `/home/whc/lintel/gcc/usr_local/bin/g++ -v` Reading specs from /home/whc/lintel/gcc/usr_local/lib/gcc-lib/i686-pc-linux-gnu/3.3.2/specs Configured with: ./configure --prefix=/home/whc/lintel/gcc/usr_local --exec-prefix=/home/whc/lintel/gcc/usr_local Thread model: posix gcc version 3.3.2 /home/whc/lintel/gcc/usr_local/bin/g++ -O3 -c -Wno-deprecated -ffast-math -mfpmath=sse y.cc cc1plus: warning: SSE instruction set disabled, using 387 arithmetics ls -ls y.o 46 -rw-r--r-- 1 whc cad 46676 Jan 29 11:05 y.o /home/whc/lintel/gcc/usr_local/bin/g++ -O3 -o y y.o /bin/csh -c "(setenv LD_LIBRARY_PATH /home/whc/lintel/gcc/usr_local/lib; time y)" X422 = 469.196 30.669u 0.007s 0:31.04 98.7% 0+0k 0+0io 235pf+0w ###### USING ICC ###### /dcad/apps/intel/compiler70/ia32/bin/icc -V -c -O y.cc Intel(R) C++ Compiler for 32-bit applications, Version 7.1 Build 20030307Z Copyright (C) 1985-2003 Intel Corporation. All rights reserved. Edison Design Group C/C++ Front End, version 3.0 (Mar 8 2003 18:39:53) Copyright 1988-2002 Edison Design Group, Inc. ls -ls y.o 144 -rw-r--r-- 1 whc cad 135824 Jan 29 11:06 y.o /dcad/apps/intel/compiler70/ia32/bin/icc -o y y.o /bin/csh -c "(setenv LD_LIBRARY_PATH /dcad/apps/intel/compiler70/ia32/lib; time y)" X422 = 469.196 23.871u 0.011s 0:24.13 98.9% 0+0k 0+0io 178pf+0w [whc@juno testcase]$ > > -- > What |Removed |Added > ---------------------------------------------------------------------------- > GCC build triplet|??? | > GCC host triplet|DELL, Pentium4, Linux RedHat| > |7.3 | > GCC target triplet|??? |i686-pc-linux-gnu > > > http://gcc.gnu.org/bugzilla/show_bug.cgi?id=13712 > > ------- You are receiving this mail because: ------- > You reported the bug, or are watching the reporter. > -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=13712