From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 9842 invoked by alias); 23 Sep 2006 14:26:59 -0000 Received: (qmail 9833 invoked by uid 22791); 23 Sep 2006 14:26:59 -0000 X-Spam-Check-By: sourceware.org Received: from nevyn.them.org (HELO nevyn.them.org) (66.93.172.17) by sourceware.org (qpsmtpd/0.31.1) with ESMTP; Sat, 23 Sep 2006 14:26:52 +0000 Received: from drow by nevyn.them.org with local (Exim 4.54) id 1GR8Sw-00021J-GQ; Sat, 23 Sep 2006 10:26:50 -0400 Date: Sat, 23 Sep 2006 14:26:00 -0000 From: Daniel Jacobowitz To: Maxim Grigoriev Cc: gdb@sourceware.org, Marc Gauthier , Bob Wilson Subject: Re: Xtensa port Message-ID: <20060923142650.GA7584@nevyn.them.org> Mail-Followup-To: Maxim Grigoriev , gdb@sourceware.org, Marc Gauthier , Bob Wilson References: <45142A88.7000805@hq.tensilica.com> <20060922190726.GA8221@nevyn.them.org> <45147F94.4020701@hq.tensilica.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <45147F94.4020701@hq.tensilica.com> User-Agent: Mutt/1.5.13 (2006-08-11) X-IsSubscribed: yes Mailing-List: contact gdb-help@sourceware.org; run by ezmlm Precedence: bulk List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-owner@sourceware.org X-SW-Source: 2006-09/txt/msg00137.txt.bz2 On Fri, Sep 22, 2006 at 05:28:04PM -0700, Maxim Grigoriev wrote: > I need an FP number. And, the most reliable source for this information > is DWARF data. You're relying on the presence of DWARF symbolic debug information, and yet you can't use DWARF-2 unwinding (.debug_frame, dwarf2-frame.c) and avoid the issue entirely? And you have no way to determine this reliably from instruction scanning, like other ports do (see prologue-value.c)? I'd recommend either in preference to this. I can't tell you how much work either would be, because I don't know much about Xtensa. The problem with using DW_AT_frame_base is that there's no guarantee it is related to what you want it to be in this context. The compiler has a lot of freedom in what it places there; it's only meaningful in context of local variable locations in the same frame. For instance, you're completely ignoring any bias. > If there is no such "utility" request ( which I thought is the case ), > I'd need to introduce it. That would be an update to the generic part of > GDB. And, I was given specific instructions to avoid any updates to the > generic code, when I submit an architecture port. I don't know why. They should generally be done separately, with individual explanations, but hacking around the GDB core instead of fixing it is generally frowned upon. -- Daniel Jacobowitz CodeSourcery