From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750966AbWFKVEG (ORCPT ); Sun, 11 Jun 2006 17:04:06 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750972AbWFKVEG (ORCPT ); Sun, 11 Jun 2006 17:04:06 -0400 Received: from smtp.cs.aau.dk ([130.225.194.6]:43723 "EHLO smtp.cs.aau.dk") by vger.kernel.org with ESMTP id S1750974AbWFKVEE (ORCPT ); Sun, 11 Jun 2006 17:04:04 -0400 Message-ID: <448C85B7.1010902@labri.fr> Date: Sun, 11 Jun 2006 23:05:59 +0200 From: Emmanuel Fleury User-Agent: Thunderbird 1.5.0.2 (X11/20060516) MIME-Version: 1.0 To: Chuck Ebbert <76306.1226@compuserve.com> CC: linux-kernel Subject: Re: [patch] i386: use C code for current_thread_info() References: <200606111647_MC3-1-C228-993B@compuserve.com> In-Reply-To: <200606111647_MC3-1-C228-993B@compuserve.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Chuck Ebbert wrote: > > I just tried gcc 3.3.3 and the kernel gets a little bigger but it boots > and runs OK. That's the oldest compiler I can find. > > text data bss dec hex filename > 3593627 559864 342728 4496219 449b5b 2.6.17-rc6-32-post/vmlinux > 3591371 559864 342728 4493963 44928b 2.6.17-rc6-32/vmlinux > +2256 > > Looking at the generated code, it seems the compiler just makes dumb > choices and tends to recompute current_thread_info() in unlikely code > paths even when there is no register pressure. 4.0.2 makes better > choices. What size with gcc 4.1.2 ? (just curiosity) Regards -- Emmanuel Fleury | Office: 211 Associate Professor, | Phone: +33 (0)5 40 00 35 24 LaBRI, Domaine Universitaire | Fax: +33 (0)5 40 00 66 69 351, Cours de la Libération | email: fleury@labri.fr 33405 Talence Cedex, France | URL: http://www.labri.fr/~fleury