From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 21329 invoked by alias); 20 Mar 2012 06:53:35 -0000 Received: (qmail 21318 invoked by uid 22791); 20 Mar 2012 06:53:34 -0000 X-SWARE-Spam-Status: No, hits=-1.5 required=5.0 tests=AWL,BAYES_00 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; Tue, 20 Mar 2012 06:53:08 +0000 Received: from svr-orw-exc-10.mgc.mentorg.com ([147.34.98.58]) by relay1.mentorg.com with esmtp id 1S9swN-0007E5-PE from Yao_Qi@mentor.com for gdb-patches@sourceware.org; Mon, 19 Mar 2012 23:53:07 -0700 Received: from SVR-ORW-FEM-04.mgc.mentorg.com ([147.34.97.41]) by SVR-ORW-EXC-10.mgc.mentorg.com with Microsoft SMTPSVC(6.0.3790.4675); Mon, 19 Mar 2012 23:53:05 -0700 Received: from [127.0.0.1] (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; Mon, 19 Mar 2012 23:53:04 -0700 Message-ID: <4F68295F.80301@codesourcery.com> Date: Tue, 20 Mar 2012 06:53:00 -0000 From: Yao Qi User-Agent: Mozilla/5.0 (X11; Linux i686; rv:11.0) Gecko/20120310 Thunderbird/11.0 MIME-Version: 1.0 To: "Gustavo, Luis" CC: Subject: Re: [PATCH] Fix displaced stepping for remote targets References: <4F67E54C.1010904@mentor.com> <4F6808C9.7020709@codesourcery.com> <4F6809DB.1010005@mentor.com> In-Reply-To: <4F6809DB.1010005@mentor.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8bit 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: 2012-03/txt/msg00736.txt.bz2 On 03/20/2012 12:38 PM, Luis Gustavo wrote: > On 03/20/2012 01:34 AM, Yao Qi wrote: >> On 03/20/2012 10:02 AM, Luis Gustavo wrote: >>> If a target supports hw single-stepping for displaced stepping, GDB >>> should just send a vCont;s packet to tell the target to step a single >>> instruction. In my case, GDB was always sending a vCont;c instead. >> >> On some arch, the original instruction may be translated to more than >> one instructions, and copied to scratch pad. So, we can't do >> single-step in scratch pad. > > During a few tests x86 seems to do single-stepping in the scratch pad > when using displaced stepping, or at least it sends the correct vCont;s > packet. > GDB writes only one instruction in scratch pad on i386 and amd64. That may be the reason why no fail shows up. -- Yao (齐尧)