From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 20897 invoked by alias); 21 Jun 2002 19:14:25 -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 20881 invoked from network); 21 Jun 2002 19:14:23 -0000 Received: from unknown (HELO zwingli.cygnus.com) (208.245.165.35) by sources.redhat.com with SMTP; 21 Jun 2002 19:14:23 -0000 Received: by zwingli.cygnus.com (Postfix, from userid 442) id CFF975EA11; Fri, 21 Jun 2002 14:14:21 -0500 (EST) To: Andrew Cagney Cc: Joel Brobecker , gdb-patches@sources.redhat.com Subject: Re: [RFA] block_innermost_frame tweak References: <20020620131440.M397@gnat.com> <3D126D8A.9020908@cygnus.com> From: Jim Blandy Date: Fri, 21 Jun 2002 12:14:00 -0000 In-Reply-To: <3D126D8A.9020908@cygnus.com> Message-ID: User-Agent: Gnus/5.09 (Gnus v5.9.0) Emacs/21.1 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-SW-Source: 2002-06/txt/msg00434.txt.bz2 Andrew Cagney writes: > Is there a better name? As you note, it isn't a valid PC (it may not > even point into an instruction!). Further, it is isn't the address of > the instruction ``calling'' the ``frame''. Last time this came up > address_in_block() was used - frame_address_in_block()? I don't disagree with your objections (raised in a previous discussion) that `frame->pc - 1' isn't a proper PC. It may never have been the value of the PC register (if indeed the architecture has a register named `PC'); it doesn't even necessarily point to an instruction. That said, I feel that replacing "PC" with just "address" actually makes matters worse, not better. It's very helpful to see at a glance that a particular CORE_ADDR value is a pointer into the instruction stream. The exact semantics of the value --- is this the return address or the address of the call? do we need to apply DECR_PC_AFTER_BREAK? and so on --- is something that one uncovers when one researches the value more carefully, as with anything else. But if I'm the only one who has this reaction, then I don't mind the renaming. Is there some third terse term that indicates (or could indicate, by establishing a convention) "pointer into the instruction stream that isn't necessarily an instruction address or the value of a register"?