From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <binutils-return-40471-listarch-binutils=sources.redhat.com@sources.redhat.com>
Received: (qmail 32713 invoked by alias); 6 May 2005 14:26:09 -0000
Mailing-List: contact binutils-help@sources.redhat.com; run by ezmlm
Precedence: bulk
List-Subscribe: <mailto:binutils-subscribe@sources.redhat.com>
List-Archive: <http://sources.redhat.com/ml/binutils/>
List-Post: <mailto:binutils@sources.redhat.com>
List-Help: <mailto:binutils-help@sources.redhat.com>, <http://sources.redhat.com/ml/#faqs>
Sender: binutils-owner@sources.redhat.com
Received: (qmail 32648 invoked from network); 6 May 2005 14:26:01 -0000
Received: from unknown (HELO sccrmhc14.comcast.net) (204.127.202.59)
  by sourceware.org with SMTP; 6 May 2005 14:26:01 -0000
Received: from lucon.org ([24.6.212.230]) by comcast.net (sccrmhc14) with ESMTP
          id <2005050614260101400ea72le>; Fri, 6 May 2005 14:26:01 +0000
Received: by lucon.org (Postfix, from userid 1000)
	id 6A331646BD; Fri,  6 May 2005 07:26:00 -0700 (PDT)
Date: Fri, 06 May 2005 14:36:00 -0000
From: "H. J. Lu" <hjl@lucon.org>
To: Dave Korn <dave.korn@artimi.com>
Cc: 'Andreas Schwab' <schwab@suse.de>,
	'Jan Beulich' <JBeulich@novell.com>, binutils@sources.redhat.com
Subject: Re: [PATCH] x86: suppress emission of zero displacements in memoryoperands
Message-ID: <20050506142600.GA16872@lucon.org>
References: <jek6mcwihf.fsf@sykes.suse.de> <SERRANOB5i5Qy2LfHxw0000026a@SERRANO.CAM.ARTIMI.COM>
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <SERRANOB5i5Qy2LfHxw0000026a@SERRANO.CAM.ARTIMI.COM>
User-Agent: Mutt/1.4.1i
X-SW-Source: 2005-05/txt/msg00261.txt.bz2

On Fri, May 06, 2005 at 03:20:59PM +0100, Dave Korn wrote:
> ----Original Message----
> >From: Andreas Schwab
> >Sent: 06 May 2005 15:13
> 
> > "Dave Korn" <dave.korn@artimi.com> writes:
> > 
> >>   I'm not sure if I've fully understood the intent of this patch, ...
> 
> > The m68k assembler is doing something similar, also known as relaxing.
> 
>   Hopefully *only* if you specify --relax on the command line, no?
> 
> >> What if someone wants to write self-modifying code that stores varying
> >> offsets into that field?
> > 
> > In the m68k assembler you can force a field by adding an explicit size
> > modifier.
> 
>   Yes, I understand that; what I'm asking is if this patch of Jan's actually
> discards the field *even if* it is explicitly stated, when the offset value
> is zero.
> 

I agree. User may do it on purpose and TLS optimization may depend on
it. The same effect can be done with different instructions on x86.
Assembler shouldn't pick one which it thinks is the best.


H.J.