From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 14008 invoked by alias); 20 Dec 2012 15:20:34 -0000 Received: (qmail 13958 invoked by uid 22791); 20 Dec 2012 15:20:33 -0000 X-SWARE-Spam-Status: No, hits=-7.7 required=5.0 tests=AWL,BAYES_00,KHOP_RCVD_UNTRUST,KHOP_THREADED,RCVD_IN_DNSWL_HI,RCVD_IN_HOSTKARMA_W,T_RP_MATCHES_RCVD X-Spam-Check-By: sourceware.org Received: from mga02.intel.com (HELO mga02.intel.com) (134.134.136.20) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Thu, 20 Dec 2012 15:20:18 +0000 Received: from orsmga002.jf.intel.com ([10.7.209.21]) by orsmga101.jf.intel.com with ESMTP; 20 Dec 2012 07:20:17 -0800 X-ExtLoop1: 1 Received: from irsmsx101.ger.corp.intel.com ([163.33.3.153]) by orsmga002.jf.intel.com with ESMTP; 20 Dec 2012 07:20:16 -0800 Received: from irsmsx152.ger.corp.intel.com (163.33.192.66) by IRSMSX101.ger.corp.intel.com (163.33.3.153) with Microsoft SMTP Server (TLS) id 14.1.355.2; Thu, 20 Dec 2012 15:20:11 +0000 Received: from irsmsx102.ger.corp.intel.com ([169.254.2.95]) by IRSMSX152.ger.corp.intel.com ([169.254.6.36]) with mapi id 14.01.0355.002; Thu, 20 Dec 2012 15:20:14 +0000 From: "Metzger, Markus T" To: Jan Kratochvil CC: "palves@redhat.com" , "tromey@redhat.com" , "kettenis@gnu.org" , "gdb-patches@sourceware.org" , "markus.t.metzger@gmail.com" Subject: RE: [patch v6 00/12] branch tracing support for Atom Date: Thu, 20 Dec 2012 15:20:00 -0000 Message-ID: References: <1355760101-26237-1-git-send-email-markus.t.metzger@intel.com> <20121218091953.GF8054@host2.jankratochvil.net> <20121218135437.GA16636@host2.jankratochvil.net> <20121220071726.GA26625@host2.jankratochvil.net> <20121220112955.GA1420@host2.jankratochvil.net> In-Reply-To: <20121220112955.GA1420@host2.jankratochvil.net> Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable 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: 2012-12/txt/msg00744.txt.bz2 > -----Original Message----- > From: Jan Kratochvil [mailto:jan.kratochvil@redhat.com] > Sent: Thursday, December 20, 2012 12:30 PM > > How do you like temporarily adding debugger variables "$end", "$start",= and > > "$here" and accepting the same syntax that list and disas accept? I don= 't > > know how difficult that will be to implement, though. >=20 > I find it overengineered, "record list $end-42" I find already more > complicated than a new command "btrace list 42". My use case is to start with looking at the last 20 or so instructions. If = that's not enough, I want to look at the next 20. This would not be support= ed by just adding "record list last ". > I do not find great that current record.c numbers history one way and btr= ace > would number history the opposite way. I find the default direction shou= ld be > the same and it should be easy enough to type each time. I wanted to keep the numbering of record/replay. That's why I added those v= ariables to be able to express what I want. Personally, I find the opposite numbering, i.e. from newest to oldest, more= intuitive and more useful, since I'm typically more interested in the tail= of the trace than the head. Is the instruction number used anywhere outside "record goto"? > But I find / you are right that implementing even reverse-step is an add-= on > work, not requiring much to rewrite the existing code. The storage of hi= story > information between record.c a btrace.c needs to be completely different > anyway. >=20 > So I agree now the reverse-* compatibility is outside of the scope of the > initial commit. Glad to hear that. > > As will next and finish when inside the history. I don't know how > > much I will be able to reuse from the record/replay implementation. >=20 > Probably not at all. Just there should remain the same to_resume/to_wait > hooking. I'm not familiar with the implementation. I would expect, though, that it w= on't be enough to implement to_resume and to_wait hooks. I would rather exp= ect that I will need to implement new stepping commands. I further expect t= hat I would need to replace frame unwinding. For all other commands, I can = only hope that gdb is OK with a target that can read (not write) RIP but no= other register and that can access only code memory.=20 Regards, Markus. Intel GmbH Dornacher Strasse 1 85622 Feldkirchen/Muenchen, Deutschland Sitz der Gesellschaft: Feldkirchen bei Muenchen Geschaeftsfuehrer: Christian Lamprechter, Hannes Schwaderer, Douglas Lusk Registergericht: Muenchen HRB 47456 Ust.-IdNr./VAT Registration No.: DE129385895 Citibank Frankfurt a.M. (BLZ 502 109 00) 600119052