From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 27205 invoked by alias); 7 Aug 2006 14:39:47 -0000 Received: (qmail 27185 invoked by uid 22791); 7 Aug 2006 14:39:45 -0000 X-Spam-Check-By: sourceware.org Received: from mailrelay1.uni-rostock.de (HELO antivirus.uni-rostock.de) (139.30.8.201) by sourceware.org (qpsmtpd/0.31) with ESMTP; Mon, 07 Aug 2006 14:39:44 +0000 Received: from antivirus.exch.rz.uni-rostock.de ([127.0.0.1]) by antivirus.uni-rostock.de with Microsoft SMTPSVC(6.0.3790.1830); Mon, 7 Aug 2006 16:39:41 +0200 Received: from antivirus.uni-rostock.de (unverified) by antivirus.exch.rz.uni-rostock.de (Content Technologies SMTPRS 4.3.20) with ESMTP id for ; Mon, 7 Aug 2006 16:39:41 +0200 Received: from mail pickup service by antivirus.uni-rostock.de with Microsoft SMTPSVC; Mon, 7 Aug 2006 16:39:41 +0200 X-SCL: 5 71.32% Received: from mail.uni-rostock.de ([139.30.8.11]) by antivirus.uni-rostock.de with Microsoft SMTPSVC(6.0.3790.1830); Mon, 7 Aug 2006 16:39:28 +0200 Received: from conversion-daemon.mail2.uni-rostock.de by mail2.uni-rostock.de (iPlanet Messaging Server 5.2 HotFix 2.09 (built Nov 18 2005)) id <0J3M00D01TJPTW@mail.uni-rostock.de> (original mail from ronald.hecht@uni-rostock.de) for cgen@sourceware.org; Mon, 07 Aug 2006 16:39:28 +0200 (MEST) Received: from [139.30.201.25] (pike.e-technik.uni-rostock.de [139.30.201.25]) by mail2.uni-rostock.de (iPlanet Messaging Server 5.2 HotFix 2.09 (built Nov 18 2005)) with ESMTPS id <0J3M002ELU1LAC@mail.uni-rostock.de> for cgen@sourceware.org; Mon, 07 Aug 2006 16:39:21 +0200 (MEST) Date: Mon, 07 Aug 2006 14:39:00 -0000 From: Ronald Hecht Subject: Re: Simulator: base_insn and insn in decode.c In-reply-to: <44D273E8.4040006@redhat.com> To: cgen@sourceware.org Message-id: <44D75159.8070804@uni-rostock.de> MIME-version: 1.0 Content-type: text/plain; format=flowed; charset=ISO-8859-1 Content-transfer-encoding: 7BIT User-Agent: Mozilla Thunderbird 1.0.8-1.1.fc4 (X11/20060501) References: <44CDF0AC.6070707@uni-rostock.de> <44D270CF.30506@redhat.com> <44D273E8.4040006@redhat.com> X-IsSubscribed: yes Mailing-List: contact cgen-help@sourceware.org; run by ezmlm Precedence: bulk List-Subscribe: List-Archive: List-Post: List-Help: , Sender: cgen-owner@sourceware.org X-SW-Source: 2006-q3/txt/msg00023.txt.bz2 Dave Brolley wrote: > I forgot to address your other question which was about the difficulty > of setting entire_insn before decoding. It's a bit of a chicken and > egg situation isnt'y it? You can't set entire insn properly until you > know something about the insn, but you can't call decode without > setting entire_insn properly. I agree, that's always the case. > > Your method of calling decode twice won't work because of this. > > Most existing ports determine the insn length by looking at a few bits > in base_insn and use this information to fill entire_insn. > > I'm wondering if the decoder shouldn't be redesigned so that all it > takes is base_insn, which should be all that is necessary to identify > the insn. The extractors for each format would then read any > additional bytes as needed. There is already support for this for ISAs > with insns which are longer than an insn word. That sounds good. Actually, I'm wondering a bit why the disassembler in src/opcodes works so great and the simulator port only under certain circumstances. Anyway. CGEN is great stuff. It helps a lot. Whould you say that SID is a better choice? Does it work with gdb as SIM does? Ronald