From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 18214 invoked by alias); 4 May 2010 17:51:33 -0000 Received: (qmail 18202 invoked by uid 22791); 4 May 2010 17:51:33 -0000 X-SWARE-Spam-Status: No, hits=2.1 required=5.0 tests=AWL,BAYES_50,RCVD_IN_DNSWL_NONE,RCVD_IN_JMF_BL,SPF_SOFTFAIL X-Spam-Check-By: sourceware.org Received: from mtaout21.012.net.il (HELO mtaout21.012.net.il) (80.179.55.169) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Tue, 04 May 2010 17:51:25 +0000 Received: from conversion-daemon.a-mtaout21.012.net.il by a-mtaout21.012.net.il (HyperSendmail v2007.08) id <0L1W00800PJ7QW00@a-mtaout21.012.net.il> for gdb@sourceware.org; Tue, 04 May 2010 20:50:35 +0300 (IDT) Received: from HOME-C4E4A596F7 ([77.126.59.39]) by a-mtaout21.012.net.il (HyperSendmail v2007.08) with ESMTPA id <0L1W007WNPKASZ20@a-mtaout21.012.net.il>; Tue, 04 May 2010 20:50:35 +0300 (IDT) Date: Tue, 04 May 2010 17:51:00 -0000 From: Eli Zaretskii Subject: Re: [Discussion/Prec] The record speed up plan (Make speed like without prec) In-reply-to: To: Hui Zhu Cc: gdb@sourceware.org, msnyder@vmware.com Reply-to: Eli Zaretskii Message-id: <83k4rjv9n1.fsf@gnu.org> MIME-version: 1.0 Content-type: text/plain; charset=utf-8 Content-transfer-encoding: 8BIT References: <83iq78x1yz.fsf@gnu.org> 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: 2010-05/txt/msg00015.txt.bz2 > From: Hui Zhu > Date: Tue, 4 May 2010 10:44:17 +0800 > Cc: gdb@sourceware.org, msnyder@vmware.com > > On Sat, May 1, 2010 at 01:52, Eli Zaretskii wrote: > > > > > From: Hui Zhu > > > Date: Fri, 30 Apr 2010 21:23:20 +0800 > > > Cc: Michael Snyder > > > > > > But lucky for us that insns exec rules we know.  So most of insns > > > (There a some special, I will talk it later), if we have the a > > > inferior value(memory and reg), we can get the each value of next > > > insn. > > > > I don't see how you can do that, unless you first read the entire > > memory of the inferior.  Otherwise, when an instruction references > > some address, how do you know what value is stored at that address? > > > > You mean before or after the insn? Before, of course. > For the before, we do something like fork to record all of them. "Record" where? in GDB's memory? > > Also, what do you do with features such as shared memory, where the > > value at a given address can change beyond control of the current > > inferior, and change the result of some instruction which references > > that address? > > Agree, but we can give up of them like we give up the released memory now. IMHO, that'd be giving up too much. Prec is supposed to be a general-purpose tool, so designing it along an idea that has severe limitations from the get-go is not something I'd recommend.