Received: by 10.66.86.194 with SMTP id r2mr5888048paz.42.1352654068262;
        Sun, 11 Nov 2012 09:14:28 -0800 (PST)
Path: 6ni75279pbd.1!nntp.google.com!Xl.tags.giganews.com!border1.nntp.dca.giganews.com!nntp.giganews.com!local2.nntp.dca.giganews.com!nntp.supernews.com!news.supernews.com.POSTED!not-for-mail
NNTP-Posting-Date: Sun, 11 Nov 2012 11:14:27 -0600
Date: Sun, 11 Nov 2012 07:14:27 -1000
From: "Elizabeth D. Rather" <erat...@forth.com>
Reply-To: erat...@forth.com
Organization: FORTH, Inc.
User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.7; rv:16.0) Gecko/20121026 Thunderbird/16.0.2
MIME-Version: 1.0
Newsgroups: comp.lang.forth
Subject: Re: Questions about OpenFirmware
References: <5aa71e12-38da-48f4-a0b7-8c5ea0db7f5e@googlegroups.com>
In-Reply-To: <5aa71e12-38da-48f4-a0b7-8c5ea0db7f5e@googlegroups.com>
Message-ID: <SYSdnQ8ozpNuQQLNnZ2dnUVZ_oSdnZ2d@supernews.com>
Lines: 37
X-Trace: sv3-hrt14ZLSioo2GnunBOGpSpesdm1iecVF+SYCF1jhN83ip8ccxn7YBpD2sreHdYzxlRHwPbvWCHVvgSj!oqZkOdLqfe50dkhVkaGkrJkeL/4YRlr+Ikj1HvtJu/dIwxuY6yvTlS/NWGesvRXk5gZIkRNyf8he!57/TAqacBg==
X-Complaints-To: www.supernews.com/docs/abuse.html
X-DMCA-Complaints-To: www.supernews.com/docs/dmca.html
X-Abuse-and-DMCA-Info: Please be sure to forward a copy of ALL headers
X-Abuse-and-DMCA-Info: Otherwise we will be unable to process your complaint properly
X-Postfilter: 1.3.40
Bytes: 2933
X-Original-Bytes: 2872
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Content-Transfer-Encoding: 7bit

On 11/11/12 3:20 AM, deech wrote:
> Hi all,
> I have a couple of questions about OpenFirmware but there hasn't been any activity on the mailing list (http://www.openfirmware.info/pipermail/openfirmware/) in quite some time so I thought I'd ask here.
>
> I'm having trouble seeing how the whole thing is bootstrapped.
> For instance
> 1. there's a builder.dic binary file that's used by the forth implementation and I don't see how that is built,
> 2. I can't see the code that actually parses the Forth code and converts it to assembly.
>
> Thanks!
> -deech

The details depend on the version of Open Firmware. Apple's system 
differed significantly from Sun's, and IBM's was different still.

In most of them there is a core that was written in assembler (although 
I think Sun's was meta-compiled with Forth). And none of them actually 
compile machine language in the sense that a C compiler or a "compile to 
code" Forth does. It's a "subroutine threaded" system, in which the 
runtime code consists of sequences of calls. The reason for this is that 
it's essential to be able to decompile ("see") the content of 
definitions for debugging purposes, since the source is rarely available.

Cheers,
Elizabeth

-- 
==================================================
Elizabeth D. Rather   (US & Canada)   800-55-FORTH
FORTH Inc.                         +1 310.999.6784
5959 West Century Blvd. Suite 700
Los Angeles, CA 90045
http://www.forth.com

"Forth-based products and Services for real-time
applications since 1973."
==================================================