From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932819AbbERU2u (ORCPT ); Mon, 18 May 2015 16:28:50 -0400 Received: from terminus.zytor.com ([198.137.202.10]:52588 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932410AbbERU2s (ORCPT ); Mon, 18 May 2015 16:28:48 -0400 Message-ID: <555A4B67.4080201@zytor.com> Date: Mon, 18 May 2015 13:28:23 -0700 From: "H. Peter Anvin" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.5.0 MIME-Version: 1.0 To: "H.J. Lu" CC: Andy Lutomirski , Borislav Petkov , Jan Beulich , Binutils , "linux-kernel@vger.kernel.org" Subject: Re: Avoiding unnecessary jump relocations in gas? References: <554B6E0102000078000778D0@mail.emea.novell.com> <555A4628.4060802@zytor.com> In-Reply-To: Content-Type: multipart/mixed; boundary="------------080608030302080604070703" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This is a multi-part message in MIME format. --------------080608030302080604070703 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit On 05/18/2015 01:25 PM, H.J. Lu wrote: > On Mon, May 18, 2015 at 1:06 PM, H. Peter Anvin wrote: >> On 05/18/2015 01:02 PM, H.J. Lu wrote: >>>> >>>> I wonder if it would make sense to have explicit mnemonics for the >>>> one-byte offset and four-byte offset jump variants. Sometimes users >>>> want a jump with a 32-bit offset for reasons that have nothing to do >>>> with link-time or load-time relocations. >>>> >>> >>> There is: >>> >>> jmp.d32 foo >>> >> >> How far back does that syntax work? >> > > .d32 support was added by > > commit f8a5c266971d7b5b96f973805551c6e88669cada > Author: H.J. Lu > Date: Thu Oct 14 13:31:13 2010 +0000 > > Add .d32 encoding suffix. > > and .d8 supported was added by > > commit a501d77eeba717f6d54dce44f286f9e3aad83144 > Author: H.J. Lu > Date: Fri Jan 20 20:53:50 2012 +0000 > > Add .d8 suffix support to x86 assembler > OK, that is probably too recent. The simplest answer I think is just to .balign 16 each vector. This is init space... some extra padding really doesn't matter. 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