From owner-freebsd-hackers Sat Feb 7 21:37:55 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id VAA02794 for hackers-outgoing; Sat, 7 Feb 1998 21:37:55 -0800 (PST) (envelope-from owner-freebsd-hackers@FreeBSD.ORG) Received: from damon.com (J10ZdgpPJUxv9k2AvwQWDJym5HgNIr/z@damon.com [207.170.114.1]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id VAA02782 for ; Sat, 7 Feb 1998 21:37:48 -0800 (PST) (envelope-from dap@damon.com) Received: (from dap@localhost) by damon.com (8.8.7/8.8.7) id XAA10571; Sat, 7 Feb 1998 23:37:37 -0600 (CST) (envelope-from dap) From: Damon Permezel Message-Id: <199802080537.XAA10571@damon.com> Subject: Re: MMX, pentium, etc In-Reply-To: <199802080517.WAA17659@mt.sri.com> from Nate Williams at "Feb 7, 98 10:17:33 pm" To: nate@mt.sri.com (Nate Williams) Date: Sat, 7 Feb 1998 23:37:37 -0600 (CST) Cc: dap@damon.com, hackers@FreeBSD.ORG X-Mailer: ELM [version 2.4ME+ PL32 (25)] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG "Nate Williams sez: " > > I have a Java app which uses some intensive FP, for which I have > > written native (aka: C) routines to accelerate. > > > > I am getting to the point where I am once again tapped out, so I want > > to explore hand coded MMX instructions in my (unrolled, hand optimized) > > inner loops. > > Umm, if you're using the FPU, then MMX would be a lose if you mix FPU > and MMX instructions. Better to stick with just FPU instructions. Well, I'll make that decision when I know what the MMX instructions are. All I know is, MMX are supposed to be for multimedia, and in particular enable full-screen s/w mpeg. A lot of what I do is inverse DCT, except I go 256x256, rather than 8x8. I will probably change to an integer iDCT when I am able to see what the MMX instructions are: ie if they are all integer instructions. I suppose I should change to integer anyway, but I have been spoiled by working on machines which had decent FP performance. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe hackers" in the body of the message