From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262468AbTIEMEs (ORCPT ); Fri, 5 Sep 2003 08:04:48 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262474AbTIEMEs (ORCPT ); Fri, 5 Sep 2003 08:04:48 -0400 Received: from chello080108023209.34.11.vie.surfer.at ([80.108.23.209]:53377 "HELO leto2.endorphin.org") by vger.kernel.org with SMTP id S262468AbTIEMEp (ORCPT ); Fri, 5 Sep 2003 08:04:45 -0400 Date: Fri, 5 Sep 2003 14:04:46 +0200 To: =?iso-8859-1?Q?J=F6rn?= Engel Cc: linux-kernel@vger.kernel.org Subject: Re: nasm over gas? Message-ID: <20030905120446.GA3111@leto2.endorphin.org> References: <20030904104245.GA1823@leto2.endorphin.org> <20030905114220.GB10415@wohnheim.fh-wedel.de> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="ibTvN161/egqYuK8" Content-Disposition: inline In-Reply-To: <20030905114220.GB10415@wohnheim.fh-wedel.de> User-Agent: Mutt/1.3.28i From: Fruhwirth Clemens X-Delivery-Agent: TMDA/0.51 (Python 2.1.3 on Linux/i686) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org --ibTvN161/egqYuK8 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Fri, Sep 05, 2003 at 01:42:20PM +0200, J=F6rn Engel wrote: > On Thu, 4 September 2003 12:42:45 +0200, Fruhwirth Clemens wrote: > > Do some benchmarks on lots of different machines and measure the > performance of the asm and c code. If it's faster on PPro but not on > PIII or Athlon, forget about it. > > How big is the .text of the asm and c variant? If the text of yours > is much bigger, you just traded 2fish performance for general > performance. Everything else will suffer from cache misses. Forget > your microbenchmark, your variant will make the machine slower. Men! Why is everyone doubting the usefulness of assembler optimized parts? It's twice as fast on my Athlon. I assert the same is true for P3/P4. Just test. twofish-i586.ko's .text section is smaller than the kernel's twofish.ko's. = 945 bytes to be precise. Please note that twofish-i586 includes TWO implementations: C and assembler. Just think about how much smaller it will be when I rip out the C part.=20 So much for that. > How many bugs are in your code? =20 42... Is this a serious question? > Are there any buffer overflows or other security holes?=20 > How can you be sure about it? =20 How can you be sure? Mathematical program verification applies quite badly = to assembler. > If your code fails on any one of these questions, forget about it. If > it survives them, post your results and have someone else verify them. I'm sorry, your critique is too generel to be useful. Regards, Clemens --ibTvN161/egqYuK8 Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.0.6 (GNU/Linux) Comment: For info see http://www.gnupg.org iD8DBQE/WHveW7sr9DEJLk4RAjpdAKCU95q/hufW8F70nFcusfoJvwcBzQCcCtJZ PSfNHYVKwCwdiAhGFdf9O+s= =IKEc -----END PGP SIGNATURE----- --ibTvN161/egqYuK8--