From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 3992 invoked by alias); 18 Oct 2012 10:28:24 -0000 Received: (qmail 3982 invoked by uid 22791); 18 Oct 2012 10:28:24 -0000 X-SWARE-Spam-Status: No, hits=-4.5 required=5.0 tests=AWL,BAYES_00,KHOP_RCVD_UNTRUST,KHOP_THREADED,RCVD_IN_HOSTKARMA_W,RCVD_IN_HOSTKARMA_WL X-Spam-Check-By: sourceware.org Received: from relay1.mentorg.com (HELO relay1.mentorg.com) (192.94.38.131) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Thu, 18 Oct 2012 10:28:19 +0000 Received: from svr-orw-fem-01.mgc.mentorg.com ([147.34.98.93]) by relay1.mentorg.com with esmtp id 1TOnKq-0004c7-Gy from Yao_Qi@mentor.com ; Thu, 18 Oct 2012 03:28:16 -0700 Received: from SVR-ORW-FEM-04.mgc.mentorg.com ([147.34.97.41]) by svr-orw-fem-01.mgc.mentorg.com over TLS secured channel with Microsoft SMTPSVC(6.0.3790.4675); Thu, 18 Oct 2012 03:28:16 -0700 Received: from qiyao.dyndns.org (147.34.91.1) by svr-orw-fem-04.mgc.mentorg.com (147.34.97.41) with Microsoft SMTP Server id 14.1.289.1; Thu, 18 Oct 2012 03:28:15 -0700 Message-ID: <507FD9CB.7060805@codesourcery.com> Date: Thu, 18 Oct 2012 10:28:00 -0000 From: Yao Qi User-Agent: Mozilla/5.0 (X11; Linux i686; rv:15.0) Gecko/20120911 Thunderbird/15.0.1 MIME-Version: 1.0 To: Pedro Alves CC: Michal Lesniewski , Subject: Re: Implementation of different software breakpoint kinds in gdb server References: <000001cdad12$1e2b1950$5a814bf0$%lesniewski@samsung.com> <507FD526.5080604@redhat.com> In-Reply-To: <507FD526.5080604@redhat.com> Content-Type: text/plain; charset="ISO-8859-1"; format=flowed Content-Transfer-Encoding: 7bit X-IsSubscribed: yes Mailing-List: contact gdb-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-owner@sourceware.org X-SW-Source: 2012-10/txt/msg00080.txt.bz2 On 10/18/2012 06:08 PM, Pedro Alves wrote: > Offhand, the main issues with tracepoints on ARM are: > > #1 - gdbserver needs to know how to step over the tracepoints, without gdb's intervention. > > #2 - ARM can't hw single-step, so that needs to be done the hard way, with breakpoints > (a.k.a., software single-step). > All the logic to do that is in gdb. This conflicts with #1. > > So we'd need to teach gdbserver to software single-step. Maybe it's possible > to tell offline all the possible destinations of an instruction, so we could still > leave that logic in gdb, but I suspect not. I am wondering that it might be relatively easier to implement fast tracepoint in which step-over is not needed, if finding a jumppad is not a problem :) -- Yao