From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <gcc-return-166490-listarch-gcc=gcc.gnu.org@gcc.gnu.org>
Received: (qmail 12186 invoked by alias); 12 Jan 2011 06:04:47 -0000
Received: (qmail 12177 invoked by uid 22791); 12 Jan 2011 06:04:45 -0000
X-SWARE-Spam-Status: No, hits=-0.6 required=5.0	tests=AWL,BAYES_00,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,FREEMAIL_ENVFROM_END_DIGIT,FREEMAIL_FROM,RCVD_IN_DNSWL_LOW,RFC_ABUSE_POST
X-Spam-Check-By: sourceware.org
Received: from mail-fx0-f47.google.com (HELO mail-fx0-f47.google.com) (209.85.161.47)    by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Wed, 12 Jan 2011 06:04:42 +0000
Received: by fxm17 with SMTP id 17so222779fxm.20        for <gcc@gcc.gnu.org>; Tue, 11 Jan 2011 22:04:39 -0800 (PST)
MIME-Version: 1.0
Received: by 10.223.81.69 with SMTP id w5mr530240fak.104.1294812279573; Tue, 11 Jan 2011 22:04:39 -0800 (PST)
Received: by 10.223.70.201 with HTTP; Tue, 11 Jan 2011 22:04:39 -0800 (PST)
In-Reply-To: <mcrmxn74apa.fsf@google.com>
References: <AANLkTik2wJirOgyQ+ophpOhH-hjSv3K3Xj4DPrPk545v@mail.gmail.com>	<mcry66r5x7k.fsf@google.com>	<AANLkTi=S47fNp-1Mr8cfYS0-V3iRpN8xRrgGyE63FxR0@mail.gmail.com>	<mcr8vyr5u9v.fsf@google.com>	<AANLkTimrGVFRGkQddNj7FmAO9mT8na2VxFFgzGyfyC76@mail.gmail.com>	<mcrmxn74apa.fsf@google.com>
Date: Wed, 12 Jan 2011 06:04:00 -0000
Message-ID: <AANLkTimXqGVkBbw=sGYSUFiz4zurv_=t6dWL4W4qFNSo@mail.gmail.com>
Subject: Re: Plus Reload
From: Gidi Nave <gidi.nave.1@gmail.com>
To: Ian Lance Taylor <iant@google.com>
Cc: gcc@gcc.gnu.org
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: quoted-printable
Mailing-List: contact gcc-help@gcc.gnu.org; run by ezmlm
Precedence: bulk
List-Id: <gcc.gcc.gnu.org>
List-Archive: <http://gcc.gnu.org/ml/gcc/>
List-Post: <mailto:gcc@gcc.gnu.org>
List-Help: <http://gcc.gnu.org/ml/>
Sender: gcc-owner@gcc.gnu.org
X-SW-Source: 2011-01/txt/msg00130.txt.bz2

On Tue, Jan 11, 2011 at 7:22 PM, Ian Lance Taylor <iant@google.com> wrote:
> Gidi Nave <gidi.nave.1@gmail.com> writes:
>
>> On Tue, Jan 11, 2011 at 5:34 PM, Ian Lance Taylor <iant@google.com> wrot=
e:
>>
>>> So why doesn't d1 =3D d1 + -96 match the last instruction there?
>>>
>> because it's: =A0 =A0add d,d unsigned
>> we don't have: =A0add d,d signed
>>
>> and in this case we need: d =3D r + (-96)
>
> (Please don't top-post on this mailing list. =A0Thanks.)
>
> Addition of signed and unsigned numbers is the same operation at the
> machine level. =A0Are there limitations on the signed value? =A0If so, is
> there is a sub instruction?
>
> Ian
>


Hi Ian,

There are limitation for the signed value for D class registers.
There is a sub instruction for D registers, but it's limited to U5
(unsigned of 5 bits) which is not the case here.

Thanks,
Gidi.