From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 32160 invoked by alias); 27 Nov 2007 17:59:58 -0000 Received: (qmail 32112 invoked by uid 22791); 27 Nov 2007 17:59:58 -0000 X-Spam-Check-By: sourceware.org Received: from shell4.BAYAREA.NET (HELO shell4.bayarea.net) (209.128.82.1) by sourceware.org (qpsmtpd/0.31) with ESMTP; Tue, 27 Nov 2007 17:59:49 +0000 Received: (qmail 22044 invoked from network); 27 Nov 2007 09:59:47 -0800 Received: from 209-128-106-254.bayarea.net (HELO ?192.168.20.7?) (209.128.106.254) by shell4.bayarea.net with SMTP; 27 Nov 2007 09:59:47 -0800 Message-ID: <474C5B13.201@eagercon.com> Date: Tue, 27 Nov 2007 18:47:00 -0000 From: Michael Eager User-Agent: Thunderbird 1.5.0.9 (X11/20070102) MIME-Version: 1.0 To: "Joseph S. Myers" CC: Ross Ridge , GCC Subject: Re: BITS_PER_UNIT larger than 8 -- word addressing References: <20071127034635.ABBD773D73@caffeine.csclub.uwaterloo.ca> <474BC7B7.30400@eagercon.com> In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-IsSubscribed: yes Mailing-List: contact gcc-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Archive: List-Post: List-Help: Sender: gcc-owner@gcc.gnu.org X-SW-Source: 2007-11/txt/msg00728.txt.bz2 Joseph S. Myers wrote: > On Mon, 26 Nov 2007, Michael Eager wrote: > >> Well, can't do that. This is not target dependent. >> DImode gets defined, and used, for long long in unwind-dw2.c. > > Is it defined what DWARF unwind information looks like when made up of > bytes wider than 8 bits? Certainly GCC's code won't allow for it at > present. I expect that the unwind code is broken unless long long is 8 bytes. IIRC, unwind confuses host and target integer sizes. > The string handling code is a major area which doesn't allow for target > and host bytes being different. But everything target-independent > hardcoding integer modes wider than QImode is potentially wrong; with wide > bytes, many of those modes may not exist. IMO, it looks like the absence of a supported 32-bit word-addressed target let the support for BITS_PER_UNIT != 8 fall into disrepair. I think that there is a pervasive understanding that SImode is single precision integer, 32-bits long. -- Michael Eager eager@eagercon.com 1960 Park Blvd., Palo Alto, CA 94306 650-325-8077