From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 6969 invoked by alias); 20 May 2005 13:36:32 -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 6569 invoked from network); 20 May 2005 13:36:21 -0000 Received: from unknown (HELO smtp.hispeed.ch) (62.2.95.247) by sourceware.org with SMTP; 20 May 2005 13:36:21 -0000 Received: from indel.ch ([84.73.28.118]) by smtp.hispeed.ch (8.12.6/8.12.6/tornado-1.0) with SMTP id j4KDaKrb019220 for ; Fri, 20 May 2005 15:36:20 +0200 Received: from fabi.indel.ch [192.168.1.19] by indel.ch [127.0.0.1] with SMTP (MDaemon.v2.7.SP5.R) for ; Fri, 20 May 2005 15:35:03 +0200 Message-Id: <5.2.0.9.1.20050520153033.01dbc628@NT_SERVER> X-Sender: cenedese@NT_SERVER (Unverified) Date: Fri, 20 May 2005 13:36:00 -0000 To: gdb@sources.redhat.com From: Fabian Cenedese Subject: Re: [discuss] Support for reverse-execution In-Reply-To: <20050520131841.GC25206@nevyn.them.org> References: <20050519012254.GZ19642@erizo.shearer.org> <428C8E04.3000305@virtutech.com> <01c55d27$Blat.v2.4$69471120@zahav.net.il> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" X-MDaemon-Deliver-To: gdb@sources.redhat.com X-Return-Path: cenedese@indel.ch X-Virus-Status: Clean X-DCC-spamcheck-02.tornado.cablecom.ch-Metrics: smtp-02.tornado.cablecom.ch 32701; Body=1 Fuz1=1 Fuz2=1 X-SW-Source: 2005-05/txt/msg00213.txt.bz2 >Of course it's possible that you enter the previous line in the middle: > >= > line 1 >label: line 1 some more > line 1 a bit more >= >PC: line 2 > line 2 > >I think the way to do this is to take advantage of the fact that >reversible targets are generally (always? too early to tell perhaps) >going to be repeatable. We can single-step backwards once, enter line >1, single step backwards again, still in line 1, single-step backwards >again, we've gone too far, single-step forwards. Or, we could use a >temporary bookmark. Single-step backwards once, enter line 1, place >bookmark, single-step backwards again, good, update bookmark. Again, >oops we're somewhere else, jump to bookmark and report a stop at label. 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? Thanks bye Fabi