From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <gdb-return-8290-listarch-gdb=sourceware.cygnus.com@sources.redhat.com>
Received: (qmail 31126 invoked by alias); 4 Apr 2002 18:03:00 -0000
Mailing-List: contact gdb-help@sources.redhat.com; run by ezmlm
Precedence: bulk
List-Subscribe: <mailto:gdb-subscribe@sources.redhat.com>
List-Archive: <http://sources.redhat.com/ml/gdb/>
List-Post: <mailto:gdb@sources.redhat.com>
List-Help: <mailto:gdb-help@sources.redhat.com>, <http://sources.redhat.com/ml/#faqs>
Sender: gdb-owner@sources.redhat.com
Received: (qmail 31113 invoked from network); 4 Apr 2002 18:02:57 -0000
Received: from unknown (HELO cygnus.com) (205.180.230.5)
  by sources.redhat.com with SMTP; 4 Apr 2002 18:02:57 -0000
Received: from localhost.redhat.com (cse.cygnus.com [205.180.230.236])
	by runyon.cygnus.com (8.8.7-cygnus/8.8.7) with ESMTP id KAA03990;
	Thu, 4 Apr 2002 10:01:02 -0800 (PST)
Received: by localhost.redhat.com (Postfix, from userid 469)
	id 1B591112E4; Thu,  4 Apr 2002 12:57:00 -0500 (EST)
From: Elena Zannoni <ezannoni@redhat.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Transfer-Encoding: 7bit
Message-ID: <15532.37867.707838.943203@localhost.redhat.com>
Date: Thu, 04 Apr 2002 10:03:00 -0000
To: Andrew Cagney <ac131313@cygnus.com>
Cc: Andreas Jaeger <aj@suse.de>, Michal Ludvig <mludvig@suse.cz>,
        gdb <gdb@sources.redhat.com>
Subject: Re: discuss: How to print XMM registers on i386/x86-64
In-Reply-To: <3CAC8B94.7020904@cygnus.com>
References: <3CAC6E35.8050302@suse.cz>
	<u8sn6btrjc.fsf@gromit.moeb>
	<3CAC8B94.7020904@cygnus.com>
X-SW-Source: 2002-04/txt/msg00059.txt.bz2

Andrew Cagney writes:
 > > Michal Ludvig <mludvig@suse.cz> writes:
 > > 
 > > 
 > >> Hi all,
 > >> current gdb has a problem with printing xmm registers on i386/x86-64
 > >> architectures. XMM regsters are of type builtin_type_v4sf. In 5.1.1
 > >> the output of 'comand info registers xmm0' was as follows:
 > >>
 > >> xmm0           0x00102030405060708090a0b0c0d0e0f0
 > >> Now in current mainline it's completely broken (with the same type):
 > >>
 > >> xmm0  {f = {0x0, 0x0, 0x0, 0x0}} \
 > >> {f = {5.82303983e-10, 2.77686634e+29, -1.16826016e-09, \
 > >> -5.56616044e+29}}
 > 
 > When you say broken, you mean the output or the values?
 > 
 > >> If I change the type to builtin_type_v4si I get a more useful output:
 > >>
 > >> xmm0  {f = {0x30201000, 0x70605040, 0xb0a09080, 0xf0e0d0c0}} \
 > >> {f = {807407616, 1885360192, -1331654528, -253701952}}
 > >>
 > >> So my question is how to print it? We shouldn't treat XMM registers as
 > >> 4xFP, because it can contain 1) two double precision floats, 2) four
 > >> single precision floats, 3) from 16 bytes, 8 words, 4 double words, 2
 > >> quadwords or 1 double quadword (128b).
 > 
 > 
 > The idea behind the registers having struct/union types was to make it 
 > possible for the user to ``explore'' (and access) sub fields and the 
 > composite vis:
 > 
 > 	$xmm0.v4si[1]
 > 	$xmm0.v2di[0]
 > 
 > (don't quote me on the syntax).  It sounds like the current type isn't 
 > sufficient - a union of types is needed?
 > 
 > Can I suggest treating how ``info registers'' displays registers as a 
 > separate problem - the code is free to display the registers in what 
 > ever format it sees fit.
 > 
 > >> For now gcc won't store more than one FP variable into each register,
 > >> ie. we don't need to convert all parts to float.
 > 
 > I think the full register contents should be displayed - we can't assume 
 > that the user is using GCC.
 > 
 > Ok, one MMX patch comming right up ...
 > 
 > Andrew
 > 
 > 

Another example to look at is the printing of the AltiVec registers.
The code for this is in rs6000-tdep.c.

Elena