From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 1948 invoked by alias); 20 May 2005 15:40:48 -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 1805 invoked from network); 20 May 2005 15:40:43 -0000 Received: from unknown (HELO gorgon.vtab.com) (62.20.90.195) by sourceware.org with SMTP; 20 May 2005 15:40:43 -0000 Received: from [10.0.0.133] (despair.hq.vtech [10.0.0.133]) by gorgon.vtab.com (Postfix) with ESMTP id A0CDCB9145; Fri, 20 May 2005 17:40:42 +0200 (CEST) Message-ID: <428E04FA.9080609@virtutech.com> Date: Fri, 20 May 2005 15:40:00 -0000 From: Johan Rydberg User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7) Gecko/20040618 MIME-Version: 1.0 To: Daniel Jacobowitz Cc: Eli Zaretskii , dan@shearer.org, gdb@sources.redhat.com Subject: Re: [discuss] Support for reverse-execution References: <20050519012254.GZ19642@erizo.shearer.org> <428C8E04.3000305@virtutech.com> <01c55d27$Blat.v2.4$69471120@zahav.net.il> <20050520131348.GB25206@nevyn.them.org> In-Reply-To: <20050520131348.GB25206@nevyn.them.org> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit X-SW-Source: 2005-05/txt/msg00222.txt.bz2 Daniel Jacobowitz wrote: > Johan, when I sketched out some algorithms for implementing these > commands, I got the feeling that this was not a good way to do it. > There are just too many ways to jump, and they can be pretty tricky to > recognize on some architectures. PowerPC is easy, but it's a little > more complicated to disassemble starting from the end of an instruction > on ia32. Here's another one that requires absolutely no target support: > [...] Yes, I'm well aware of this. > [...] > i.e. build reverse-next on top of reverse-finish. reverse-finish > should take you to the intermediate caller in a tail call situation, > not to the previous frame on the stack. This approach has also crossed my mind, and minimizing the need for target dependent code is worthwhile goal. I'll see if I can hack something up during the weekend. I guess the changes should not be that big. ~j