From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 26418 invoked by alias); 23 Jan 2008 15:39:45 -0000 Received: (qmail 26409 invoked by uid 22791); 23 Jan 2008 15:39:44 -0000 X-Spam-Check-By: sourceware.org Received: from igw2.br.ibm.com (HELO igw2.br.ibm.com) (32.104.18.25) by sourceware.org (qpsmtpd/0.31) with ESMTP; Wed, 23 Jan 2008 15:39:15 +0000 Received: from mailhub1.br.ibm.com (mailhub1 [9.18.232.109]) by igw2.br.ibm.com (Postfix) with ESMTP id 25CCE17F468 for ; Wed, 23 Jan 2008 13:33:00 -0200 (BRDT) Received: from d24av02.br.ibm.com (d24av02.br.ibm.com [9.18.232.47]) by mailhub1.br.ibm.com (8.13.8/8.13.8/NCO v8.7) with ESMTP id m0NFdAJ54050978 for ; Wed, 23 Jan 2008 13:39:10 -0200 Received: from d24av02.br.ibm.com (loopback [127.0.0.1]) by d24av02.br.ibm.com (8.12.11.20060308/8.13.3) with ESMTP id m0NFd9fK020280 for ; Wed, 23 Jan 2008 13:39:10 -0200 Received: from [9.18.238.41] (dyn531774.br.ibm.com [9.18.238.41]) by d24av02.br.ibm.com (8.12.11.20060308/8.12.11) with ESMTP id m0NFd9nh020277; Wed, 23 Jan 2008 13:39:09 -0200 Subject: Re: Printing decimal128 types out of registers From: Thiago Jung Bauermann To: Mark Kettenis Cc: drow@false.org, luisgpm@linux.vnet.ibm.com, gdb-patches@sourceware.org In-Reply-To: <200801211730.m0LHUGbu021315@brahms.sibelius.xs4all.nl> References: <1194460412.6686.34.camel@localhost> <1200596592.27321.20.camel@gargoyle> <1200598580.32125.11.camel@localhost.localdomain> <1200670954.10815.1.camel@gargoyle> <20080119000423.GA15057@caradoc.them.org> <1200927274.32125.36.camel@localhost.localdomain> <200801211730.m0LHUGbu021315@brahms.sibelius.xs4all.nl> Content-Type: text/plain Date: Wed, 23 Jan 2008 15:39:00 -0000 Message-Id: <1201102749.11950.66.camel@localhost.localdomain> Mime-Version: 1.0 X-Mailer: Evolution 2.12.2 Content-Transfer-Encoding: 7bit X-IsSubscribed: yes 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: 2008-01/txt/msg00554.txt.bz2 On Mon, 2008-01-21 at 18:30 +0100, Mark Kettenis wrote: > There's nothing wrong with the pseudo-register approach. In fact it > is used on many other architectures. For example sparc64, where pairs > of single-precision floating point numbers are used for > double-precision, and four registers are used for quadruple precision. > And on i386 we have the MMX registers that provide a different view on > the floating-point registers. I only think adding the whole tdesc > machinery around it is a bit too much. Ah, ok. I had misunderstood. > If dlN is > a widely accepted name for the decimal float registers, I think those > registers should be added. Actually, it's not a "widely accepted name". dl is the suffix used to indicate _Decimal128 constants in C, so Luis chose it for the register names as well. The Power ISA uses a notation FRXp, where p for "register pair". The instructions use the number of the first float register in the pair. We could use $f0p to refer to register pair starting at $f0, but I'm not sure it would be more intuitive than $dl0. I guess in both cases the user would need to have previous knowledge or look it up in the manual. -- []'s Thiago Jung Bauermann Software Engineer IBM Linux Technology Center