From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030503AbXBGA7l (ORCPT ); Tue, 6 Feb 2007 19:59:41 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1030504AbXBGA7l (ORCPT ); Tue, 6 Feb 2007 19:59:41 -0500 Received: from terminus.zytor.com ([192.83.249.54]:34517 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1030503AbXBGA7l (ORCPT ); Tue, 6 Feb 2007 19:59:41 -0500 Message-ID: <45C9246F.9050300@zytor.com> Date: Tue, 06 Feb 2007 16:59:27 -0800 From: "H. Peter Anvin" User-Agent: Thunderbird 1.5.0.9 (X11/20061219) MIME-Version: 1.0 To: Etienne Lorrain CC: "Eric W. Biederman" , vgoyal@in.ibm.com, linux-kernel@vger.kernel.org Subject: Re: Re : Re : Re : Re : [PATCH] Compressed ia32 ELF file generation for loading by Gujin 1/3 References: <965140.82745.qm@web26914.mail.ukl.yahoo.com> In-Reply-To: <965140.82745.qm@web26914.mail.ukl.yahoo.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Etienne Lorrain wrote: > H. Peter Anvin wrote: >> I've long wished that someone would do a proper 16-bit x86 port of gcc; > >> however, the .code16gcc is usually good enough, although it produces >> code which is a lot bigger than it needs to be. > > It is only that much bigger if you compare to 16 bits integer compilers, > but once you deal with 32 bits integers in real mode you have one extra byte > out of the two - which is still better than dealing with dx:ax. > > Last time I compiled (long time ago) some piece of code with and without > .code16gcc it was approx 15% bigger - approx what you get when optimising. > That's not a valid comparison, because you're using 32-bit registers to hold 16-bit pointers, and then sticking 67 prefixes on completely unnecessarily. -hpa