From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 21101 invoked by alias); 12 Mar 2010 04:23:16 -0000 Received: (qmail 21088 invoked by uid 22791); 12 Mar 2010 04:23:14 -0000 X-SWARE-Spam-Status: No, hits=-2.5 required=5.0 tests=AWL,BAYES_00 X-Spam-Check-By: sourceware.org Received: from mail.codesourcery.com (HELO mail.codesourcery.com) (38.113.113.100) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Fri, 12 Mar 2010 04:23:11 +0000 Received: (qmail 17571 invoked from network); 12 Mar 2010 04:23:09 -0000 Received: from unknown (HELO orlando.localnet) (pedro@127.0.0.2) by mail.codesourcery.com with ESMTPA; 12 Mar 2010 04:23:09 -0000 From: Pedro Alves To: gdb-patches@sourceware.org, Eli Zaretskii Subject: Re: PATCH: Support x86 pseudo registers Date: Fri, 12 Mar 2010 04:23:00 -0000 User-Agent: KMail/1.12.2 (Linux/2.6.31-19-generic; KDE/4.3.2; x86_64; ; ) Cc: "H.J. Lu" , msnyder@vmware.com References: <20100301170152.GA20106@intel.com> <6dc9ffc81003021407l27b513cbm288d1fd1e43d0c46@mail.gmail.com> <83sk8h2tum.fsf@gnu.org> In-Reply-To: <83sk8h2tum.fsf@gnu.org> MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <201003120423.07852.pedro@codesourcery.com> X-IsSubscribed: yes Mailing-List: contact gdb-patches-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sourceware.org X-SW-Source: 2010-03/txt/msg00433.txt.bz2 On Wednesday 03 March 2010 17:33:21, Eli Zaretskii wrote: > * X86 general purpose registers > > GDB now supports reading/writing byte, word and double-word x86 > general purpose registers directly. This means you can use, say, > $ah or $ax to refer, respectively, to the byte register AH and > 16-bit word register AX that are actually portions of the 32-bit > register EAX or 64-bit register RAX. > I just realized that this change means that $sp is now just a 16-bit word of $esp, instead of a pseudo-register resolving to either $esp/$rsp (32-bit/64-bit). I can't say it is actually wrong to have it that way, but, I think this should at least be mentioned in NEWS, if not in the manual too, because it can catch people by surprise. old: (top-gdb) p $sp $1 = (void *) 0x7fffffffdff0 (top-gdb) ptype $sp type = void * new: (top-gdb) p $sp $2 = -8176 (top-gdb) ptype $sp type = int16_t (top-gdb) -- Pedro Alves