From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 16606 invoked by alias); 20 May 2005 13:47:10 -0000 Mailing-List: contact gdb-help@sources.redhat.com; run by ezmlm Precedence: bulk List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-owner@sources.redhat.com Received: (qmail 16176 invoked from network); 20 May 2005 13:46:45 -0000 Received: from unknown (HELO nevyn.them.org) (66.93.172.17) by sourceware.org with SMTP; 20 May 2005 13:46:45 -0000 Received: from drow by nevyn.them.org with local (Exim 4.50) id 1DZ7ps-000763-Fo; Fri, 20 May 2005 09:46:44 -0400 Date: Fri, 20 May 2005 13:47:00 -0000 From: Daniel Jacobowitz To: Fabian Cenedese Cc: gdb@sources.redhat.com Subject: Re: [discuss] Support for reverse-execution Message-ID: <20050520134644.GA27252@nevyn.them.org> Mail-Followup-To: Fabian Cenedese , gdb@sources.redhat.com References: <20050519012254.GZ19642@erizo.shearer.org> <428C8E04.3000305@virtutech.com> <01c55d27$Blat.v2.4$69471120@zahav.net.il> <5.2.0.9.1.20050520153033.01dbc628@NT_SERVER> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <5.2.0.9.1.20050520153033.01dbc628@NT_SERVER> User-Agent: Mutt/1.5.8i X-SW-Source: 2005-05/txt/msg00214.txt.bz2 On Fri, May 20, 2005 at 03:36:23PM +0200, Fabian Cenedese wrote: > I followed this thread more out of curiosity than really need for this feature. > That doesn't mean that we still couldn't use it one day :) > > I wondered though if this stepping backwards was more than just a simple > setting of the program counter. If I step back over a i++, will it also get > decremented? Or flags, they can't possibly be restored to what they > were before e.g. a comparison, not without keeping a history. So these > r-commands are merely other variants of "set next instruction", possibly > with creating/releasing stack frames but without adjusting values according > to the stepped over commands. Is this correct? No, that's not correct. That's why the only target that supports this at the moment is a simulator; it actually undoes the instructions and allows them to replay. -- Daniel Jacobowitz CodeSourcery, LLC