From mboxrd@z Thu Jan 1 00:00:00 1970 Received: (from majordomo@localhost) by oss.sgi.com (8.11.2/8.11.3) id f7G7j6c16723 for linux-mips-outgoing; Thu, 16 Aug 2001 00:45:06 -0700 Received: from mx.mips.com (mx.mips.com [206.31.31.226]) by oss.sgi.com (8.11.2/8.11.3) with SMTP id f7G7j4j16719 for ; Thu, 16 Aug 2001 00:45:04 -0700 Received: from newman.mips.com (ns-dmz [206.31.31.225]) by mx.mips.com (8.9.3/8.9.0) with ESMTP id AAA28991; Thu, 16 Aug 2001 00:44:52 -0700 (PDT) Received: from copfs01.mips.com (copfs01 [192.168.205.101]) by newman.mips.com (8.9.3/8.9.0) with ESMTP id AAA14177; Thu, 16 Aug 2001 00:44:53 -0700 (PDT) Received: from mips.com (copsun17 [192.168.205.27]) by copfs01.mips.com (8.11.4/8.9.0) with ESMTP id f7G7hOa07187; Thu, 16 Aug 2001 09:43:32 +0200 (MEST) Message-ID: <3B7B799B.BCFD1B5E@mips.com> Date: Thu, 16 Aug 2001 09:43:23 +0200 From: Carsten Langgaard X-Mailer: Mozilla 4.75 [en] (X11; U; SunOS 5.7 sun4u) X-Accept-Language: en MIME-Version: 1.0 To: Atsushi Nemoto CC: wgowcher@yahoo.com, linux-mips@oss.sgi.com Subject: Re: Benchmark performance References: <20010809215522.A1958@lucon.org> <20010813173446.61234.qmail@web11901.mail.yahoo.com> <20010816125652N.nemoto@toshiba-tops.co.jp> Content-Type: text/plain; charset=iso-8859-15 Content-Transfer-Encoding: 7bit Sender: owner-linux-mips@oss.sgi.com Precedence: bulk Atsushi Nemoto wrote: > >>>>> On Mon, 13 Aug 2001 10:34:46 -0700 (PDT), Wayne Gowcher said: > wgowcher> a 23 % reduction in the Floating Point Index benchmark > > Current CVS kernel uses FPU emulator unconditionally. If one floating > point intruction causes a 'Unimplemented' exception (denormalized > result, etc.) following floating point instructions are also handle by > FPU emulator (not only the instruction which raise the exception). You got a point here, no need to emulate following floating point instructions, if one got a real FPU. But I think the check in the FP emulator should be a check if we got a real FPU, instead of a counter. We already has a flag for that in mips_cpu.options. The check could be something like: if (mips_cpu.options & MIPS_CPU_FPU) break; > > I do not know this is really desired behavior, but here is a patch to > change this. If Unimplemented exception had been occured during the > benchmark, aplying this patch may result better performance. > > --- > Atsushi Nemoto > > ------------------------------------------------------------------------ > Name: fpu_emu.patch > fpu_emu.patch Type: Plain Text (Text/Plain) > Encoding: 7bit -- _ _ ____ ___ Carsten Langgaard Mailto:carstenl@mips.com |\ /|||___)(___ MIPS Denmark Direct: +45 4486 5527 | \/ ||| ____) Lautrupvang 4B Switch: +45 4486 5555 TECHNOLOGIES 2750 Ballerup Fax...: +45 4486 5556 Denmark http://www.mips.com