From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 22144 invoked by alias); 4 Aug 2006 16:24:24 -0000 Received: (qmail 21997 invoked by uid 48); 4 Aug 2006 16:24:17 -0000 Date: Fri, 04 Aug 2006 16:24:00 -0000 Message-ID: <20060804162417.21996.qmail@sourceware.org> X-Bugzilla-Reason: CC References: Subject: [Bug target/27827] [4.0/4.1/4.2 Regression] gcc 4 produces worse x87 code on all platforms than gcc 3 In-Reply-To: Reply-To: gcc-bugzilla@gcc.gnu.org To: gcc-bugs@gcc.gnu.org From: "whaley at cs dot utsa dot edu" 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 X-SW-Source: 2006-08/txt/msg00271.txt.bz2 List-Id: ------- Comment #31 from whaley at cs dot utsa dot edu 2006-08-04 16:24 ------- Paolo, Thanks for the update. I attempted to apply this patch, but apparantly I failed, as it made absolutely no difference. I mean, not only did it not change performance, but if you diff the assembly, you get only 4 lines different (version numbers and use of ffreep rather than fstp). Here is what I did: > 59 10:29 cd gcc-4.1.1/ > 60 10:30 pushd gcc/config/i386/ > 62 10:30 patch < ~/x87patch > 64 10:31 cd ../../.. > 67 10:31 mkdir MyObj > 68 10:31 cd MyObj/ > 71 10:32 ../configure --prefix=/home/whaley/local/gcc4.1.1p1 --enable-languages=c,fortran > 72 10:32 make > 73 10:58 make install I did this on my P4e (IA32) and Athlon64 X2 (x86-64) machines. I did have to hand-edit the patch, due to line breaks in mouse-copying from the webpage (it wouldn't apply until I did that), so maybe that is the problem. Can you grab the mmbench4s.tar.gz attachment, and point its Makefile at your modified compiler, and tell it "make assall", and see if the generated dmm_4.s and smm_4.s are different than what you get with stock 4.1.1? If so, post them as attachments, and I can probably hack the benchmark to load the assembly, as I did on the Core. Assuming they are different, maybe you can check that this is the only patch I need to make? If it is, is there something wrong with the way I applied it? If not, maybe you should post the patch file as an attachment so we can rule out copying error . . . Thanks, Clint -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=27827