Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932331AbZAREYm (ORCPT ); Sat, 17 Jan 2009 23:24:42 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1763666AbZAREWX (ORCPT ); Sat, 17 Jan 2009 23:22:23 -0500 Received: from hera.kernel.org ([140.211.167.34]:37901 "EHLO hera.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1763660AbZAREWW (ORCPT ); Sat, 17 Jan 2009 23:22:22 -0500 Message-ID: <4972AE71.2030506@kernel.org> Date: Sun, 18 Jan 2009 13:22:09 +0900 From: Tejun Heo User-Agent: Thunderbird 2.0.0.19 (X11/20081227) MIME-Version: 1.0 To: Brian Gerst CC: Ingo Molnar , linux-kernel@vger.kernel.org Subject: Re: [PATCH 12/17] x86-64: Use absolute displacements for per-cpu accesses. References: <73c1f2160901160610l57e31a64j56fe9544bd2fd309@mail.gmail.com> <1232115396-26367-1-git-send-email-brgerst@gmail.com> <1232115396-26367-2-git-send-email-brgerst@gmail.com> <1232115396-26367-3-git-send-email-brgerst@gmail.com> <1232115396-26367-4-git-send-email-brgerst@gmail.com> <1232115396-26367-5-git-send-email-brgerst@gmail.com> <1232115396-26367-6-git-send-email-brgerst@gmail.com> <1232115396-26367-7-git-send-email-brgerst@gmail.com> <1232115396-26367-8-git-send-email-brgerst@gmail.com> <1232115396-26367-9-git-send-email-brgerst@gmail.com> <1232115396-26367-10-git-send-email-brgerst@gmail.com> <1232115396-26367-11-git-send-email-brgerst@gmail.com> <1232115396-26367-12-git-send-email-brgerst@gmail.com> In-Reply-To: <1232115396-26367-12-git-send-email-brgerst@gmail.com> X-Enigmail-Version: 0.95.7 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.0 (hera.kernel.org [127.0.0.1]); Sun, 18 Jan 2009 04:22:08 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 770 Lines: 22 Hello, Brian. Brian Gerst wrote: > Accessing memory through %gs should not use rip-relative addressing. > Adding a P prefix for the argument tells gcc to not add (%rip) to > the memory references. Nice catch. I dind't know about the P prefix thing. It also is used in other places too. Hmmm... I can't find anything about the P argument prefix in the gcc info page (4.3). Any ideas where I can find some information about it? It's a bit weird that it's not a constraint prefix but an argument one. Thanks. -- tejun -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/