From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <gdb-return-41089-listarch-gdb=sources.redhat.com@sourceware.org>
Received: (qmail 15873 invoked by alias); 26 Jun 2012 19:48:06 -0000
Received: (qmail 15827 invoked by uid 22791); 26 Jun 2012 19:48:04 -0000
X-SWARE-Spam-Status: No, hits=-5.0 required=5.0	tests=AWL,BAYES_00,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FROM,KHOP_RCVD_TRUST,KHOP_THREADED,RCVD_IN_DNSWL_LOW,RCVD_IN_HOSTKARMA_YE
X-Spam-Check-By: sourceware.org
Received: from mail-qa0-f41.google.com (HELO mail-qa0-f41.google.com) (209.85.216.41)    by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Tue, 26 Jun 2012 19:47:51 +0000
Received: by qabg27 with SMTP id g27so2423188qab.0        for <multiple recipients>; Tue, 26 Jun 2012 12:47:50 -0700 (PDT)
MIME-Version: 1.0
Received: by 10.224.188.140 with SMTP id da12mr27053073qab.42.1340740070643; Tue, 26 Jun 2012 12:47:50 -0700 (PDT)
Received: by 10.229.192.129 with HTTP; Tue, 26 Jun 2012 12:47:50 -0700 (PDT)
In-Reply-To: <ccd4a6ab-f279-477f-b48b-94b8f4afd37d@googlegroups.com>
References: <CAMe9rOqE84CeCEZHxahccP2obgb50zdJWuY0z3UzWnDYn=g_4A@mail.gmail.com>	<ccd4a6ab-f279-477f-b48b-94b8f4afd37d@googlegroups.com>
Date: Tue, 26 Jun 2012 19:48:00 -0000
Message-ID: <CAMe9rOqhnmcUhjO8SH6Ggz-VmyGFyuDrMHJU27HjKV+UM1RASA@mail.gmail.com>
Subject: Re: [x86-64 psABI] RFC: Extend x86-64 psABI to support x32
From: "H.J. Lu" <hjl.tools@gmail.com>
To: x32-abi@googlegroups.com
Cc: discuss@x86-64.org, GCC Development <gcc@gcc.gnu.org>, Binutils <binutils@sourceware.org>, 	GNU C Library <libc-alpha@sourceware.org>, GDB <gdb@sourceware.org>
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: quoted-printable
Mailing-List: contact gdb-help@sourceware.org; run by ezmlm
Precedence: bulk
List-Id: <gdb.sourceware.org>
List-Subscribe: <mailto:gdb-subscribe@sourceware.org>
List-Archive: <http://sourceware.org/ml/gdb/>
List-Post: <mailto:gdb@sourceware.org>
List-Help: <mailto:gdb-help@sourceware.org>, <http://sourceware.org/ml/#faqs>
Sender: gdb-owner@sourceware.org
X-SW-Source: 2012-06/txt/msg00086.txt.bz2

On Tue, Jun 26, 2012 at 12:36 PM, Mark Butler <butlerm@middle.net> wrote:
> On Monday, May 14, 2012 11:31:11 AM UTC-6, H.J. wrote:
>>
>> Support for the x32 psABI:
>>
>> http://sites.google.com/site/x32abi/
>>
>> is added in Linux kernel 3.4-rc1. =A0X32 uses the ILP32 model for x86-64
>> instruction set with size of long and pointers =3D=3D 4 bytes. =A0X32 is
>> already supported in GCC 4.7.0 and binutils 2.22...Here is a
>> patch to extend x86-64 psABI for x32. =A0Any comments?
>>
>
> May I ask why the decision was made to use ILP32 instead of L64P32? =A0 T=
he
> latter would seem to avoid lots of porting problems in particular. =A0And=
 if
> porting difficulties are the major complained about x32, is it really too
> late to switch? =A0Thanks - mdb

x32 is designed to replace ia32 where long is 32-bit, not x86-64.


--=20
H.J.