From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 21178 invoked by alias); 21 Feb 2002 22:58:43 -0000 Mailing-List: contact gdb-patches-help@sources.redhat.com; run by ezmlm Precedence: bulk List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sources.redhat.com Received: (qmail 21100 invoked from network); 21 Feb 2002 22:58:39 -0000 Received: from unknown (HELO gash2.peakpeak.com) (207.174.178.17) by sources.redhat.com with SMTP; 21 Feb 2002 22:58:39 -0000 Received: from creche.cygnus.com (ta0207.peakpeak.com [204.144.244.207]) by gash2.peakpeak.com (8.9.3/8.9.3) with ESMTP id PAA32519; Thu, 21 Feb 2002 15:58:34 -0700 Received: (from tromey@localhost) by creche.cygnus.com (8.9.3/8.9.3) id QAA22205; Thu, 21 Feb 2002 16:23:53 -0700 To: Jim Blandy Cc: gdb-patches@sources.redhat.com Subject: Re: Patch: Dwarf2 reader -vs- DW_OP_piece References: <87664qej9l.fsf@creche.redhat.com> From: Tom Tromey Reply-To: tromey@redhat.com X-Attribution: Tom X-Zippy: But was he mature enough last night at the lesbian masquerade? Date: Thu, 21 Feb 2002 14:58:00 -0000 In-Reply-To: Jim Blandy's message of "21 Feb 2002 17:09:42 -0500" Message-ID: <87zo22ctbq.fsf@creche.redhat.com> X-Mailer: Gnus v5.7/Emacs 20.5 X-SW-Source: 2002-02/txt/msg00614.txt.bz2 >>>>> "Jim" == Jim Blandy writes: Jim> Can you explain what sorts of location expressions this is Jim> supposed to help GDB handle? Yes, sorry. Suppose a value spans multiple registers. Currently gcc encodes this as DW_OP_reg for the first register. However, I believe that is not fully correct according to the Dwarf-2 spec. The gcc patch changes the output in this case to a series of DW_OP_reg/DW_OP_piece instructions. So previously gcc could generate this for a `long long' value (on x86 Linux): DW_OP_reg1 With the patch gcc will now generate: DW_OP_reg1 DW_OP_piece 4 DW_OP_reg2 DW_OP_piece 4 Tom