From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261716AbVFPD1i (ORCPT ); Wed, 15 Jun 2005 23:27:38 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261715AbVFPD1i (ORCPT ); Wed, 15 Jun 2005 23:27:38 -0400 Received: from chilli.pcug.org.au ([203.10.76.44]:19144 "EHLO smtps.tip.net.au") by vger.kernel.org with ESMTP id S261719AbVFPD1b (ORCPT ); Wed, 15 Jun 2005 23:27:31 -0400 Date: Thu, 16 Jun 2005 13:26:59 +1000 From: Stephen Rothwell To: Bodo Eggert <7eggert@gmx.de> Cc: macro@linux-mips.org, linux-os@analogic.com, gene.heskett@verizon.net, cutaway@bellsouth.net, linux-kernel@vger.kernel.org Subject: Re: .../asm-i386/bitops.h performance improvements Message-Id: <20050616132659.65a72842.sfr@canb.auug.org.au> In-Reply-To: References: <4fB8l-73q-9@gated-at.bofh.it> <4fF2j-1Lo-19@gated-at.bofh.it> X-Mailer: Sylpheed version 1.0.4 (GTK+ 1.2.10; i386-pc-linux-gnu) Mime-Version: 1.0 Content-Type: multipart/signed; protocol="application/pgp-signature"; micalg="PGP-SHA1"; boundary="Signature=_Thu__16_Jun_2005_13_26_59_+1000_5Zf8VOvDIN4/MKBp" Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org --Signature=_Thu__16_Jun_2005_13_26_59_+1000_5Zf8VOvDIN4/MKBp Content-Type: text/plain; charset=US-ASCII Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Wed, 15 Jun 2005 21:10:26 +0200 (CEST) Bodo Eggert <7eggert@gmx.de> wrot= e: > > My documentation says: >=20 > lea reg16, mem > Available on 8086, 80186, 80286, 80386, 80486 > 32-bit-extension available > Opcode: 8D mod reg r/m >=20 > reg will be the target register (AX .. DI), and mod and r/m will select > something like a direct address, a register or a combination like=20 > BP+DI+ofs (I won't copy the table). A multiplier is not mentioned there. In 32 bit mode on the 386 and above, a two byte version of the "mod reg r/m" is possible which contains the scaling field ... On the 386, using a second register in the ea calculation costs another cycle. --=20 Cheers, Stephen Rothwell sfr@canb.auug.org.au http://www.canb.auug.org.au/~sfr/ --Signature=_Thu__16_Jun_2005_13_26_59_+1000_5Zf8VOvDIN4/MKBp Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.1 (GNU/Linux) iD8DBQFCsPGL4CJfqux9a+8RAgQXAJ9nDzcq2m3fY5oujfgk1Ww/ENWLMQCfUA+g 3kZU3xoam6BPvqKpyMcwsLw= =F+zj -----END PGP SIGNATURE----- --Signature=_Thu__16_Jun_2005_13_26_59_+1000_5Zf8VOvDIN4/MKBp--