From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 20203 invoked by alias); 7 Jan 2003 03:11:51 -0000 Mailing-List: contact gcc-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Archive: List-Post: List-Help: Sender: gcc-owner@gcc.gnu.org Received: (qmail 20168 invoked from network); 7 Jan 2003 03:11:50 -0000 Received: from unknown (HELO nile.gnat.com) (205.232.38.5) by 209.249.29.67 with SMTP; 7 Jan 2003 03:11:50 -0000 Received: by nile.gnat.com (Postfix, from userid 338) id 29E12F2940; Mon, 6 Jan 2003 22:11:38 -0500 (EST) To: ja_walker@earthlink.net, mstump@apple.com Subject: Re: Sythetic registers: modrm/gas question. Cc: gcc@gcc.gnu.org Message-Id: <20030107031138.29E12F2940@nile.gnat.com> Date: Tue, 07 Jan 2003 03:13:00 -0000 From: dewar@gnat.com (Robert Dewar) X-SW-Source: 2003-01/txt/msg00321.txt.bz2 > You will want to learn how to ask GAS these questions. Hint, type in > the assembly, run as foo.s, and then objdump (maybe -d) the result. > This is faster and generally more accurate than asking us. Actually, I disagree with this. An experiment like this can only tell you that in a particular situation, GAS does a particular thing. An experiment cannot tell you the general rules, and the generated code must rely on these rules, which need to be clearly stated. In fact I don't know whether there are clearly stated rules for GAS, though in this particular case it is obvious that GAS must minimize offsets, since if it did not, that would have the status of being a clear bug.