From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 8424 invoked by alias); 27 Mar 2008 13:37:05 -0000 Received: (qmail 8368 invoked by uid 22791); 27 Mar 2008 13:37:03 -0000 X-Spam-Check-By: sourceware.org Received: from mail.codesourcery.com (HELO mail.codesourcery.com) (65.74.133.4) by sourceware.org (qpsmtpd/0.31) with ESMTP; Thu, 27 Mar 2008 13:36:38 +0000 Received: (qmail 16597 invoked from network); 27 Mar 2008 13:36:36 -0000 Received: from unknown (HELO localhost) (vladimir@127.0.0.2) by mail.codesourcery.com with ESMTPA; 27 Mar 2008 13:36:36 -0000 From: Vladimir Prus To: "Marc Khouzam" Subject: Re: -var-update @ Date: Thu, 27 Mar 2008 13:37:00 -0000 User-Agent: KMail/1.9.6 (enterprise 0.20070907.709405) Cc: "Nick Roberts" , gdb-patches@sources.redhat.com References: <6D19CA8D71C89C43A057926FE0D4ADAA04290FD3@ecamlmw720.eamcs.ericsson.se> In-Reply-To: <6D19CA8D71C89C43A057926FE0D4ADAA04290FD3@ecamlmw720.eamcs.ericsson.se> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-15" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200803271636.34435.vladimir@codesourcery.com> 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: 2008-03/txt/msg00433.txt.bz2 On Thursday 27 March 2008 16:24:40 Marc Khouzam wrote: > > > Incidentally, it seems to be that a really smart frontend might be updating only > > those variable objects that a visible on screen. To support this case efficiently, > > we'd better support > > > > -var-update var1 var2 var3 ... > > > > syntax. I'm not proposing such a syntax right now -- we'd need to actually play > > with such a smart frontend. > > DSF only updates varObj that are visible on screen. > So currently, it always uses -var-update with a single varObj name (never use *). > > If I understand correctly, > > -var-update var1 var2 var3 ... > would allow the frontend to update multiple variable objects with a single command. > With the goal of reducing the number of MI commands. Any other benefits? Someday, GDB might be able to batch requests to the targets. So, instead of N roundtrips over slow JTAG connection, you can have single one. > In the case of DSF, we wouldn't be able to use such a command though. > The reason is that the views which show the variables are de-coupled from the > variable object manager; and those views request the value of each variable > individually, so the variable manager, which sends -var-update only gets > a single varObj request at a time. Heh, that's what you get for using nice component design :-) Of course, batching requests in GDB might prove even more complicated. > Not to say that > > -var-update var1 var2 var3 ... > would not be useful to other "really smart frontends" :-) > > And, who knows, it may not be too hard for the DSF views to send batch requests > containing all the visible variable objects, someday. Yes. - Volodya