Release notes for Gavare's eXperimental Emulator (GXemul), 0.3.5
================================================================

Copyright (C) 2003-2005  Anders Gavare.


GXemul is an experimental instruction-level machine emulator. It can be used to
run binary code for MIPS-based machines, regardless of host platform. Several
emulation modes are available. For some modes, processors and surrounding
hardware components are emulated well enough to let unmodified operating
systems (e.g. NetBSD) run as if they were running on a real machine.

(Non-MIPS emulation modes are also under development, but so far none of those
modes has reached the completeness required to run unmodified operating
systems.) 

I have verified that the following "guest" operating systems can run inside
the emulator:

    Guest operating system             Emulated machine
    ----------------------             ----------------
    NetBSD/pmax 2.0.2 (and 1.6.2)      DECstation 5000/200
    OpenBSD/pmax 2.8-BETA              DECstation 5000/200
    Ultrix 4.2-4.5                     DECstation 5000/200
    Sprite demo harddisk image         DECstation 5000/200
    Debian GNU/Linux for DECstation    DECstation 5000/200
    Redhat Linux 7.1 for mips          DECstation 5000/200
    NetBSD/arc 1.6.2                   Acer PICA-61
    OpenBSD/arc 2.3                    Acer PICA-61
    NetBSD/hpcmips 2.0.2               NEC MobilePro 770, 780, 800, 880
    NetBSD/cobalt 2.0.2                Cobalt
    NetBSD/evbmips 2.0.2               Malta 5Kc/4Kc evaluation board
    NetBSD/sgimips 2.0.2               SGI O2 ("IP32")

Some of these guest operating systems are easier to install and run than
others. The best supported mode is the DECstation 5000/200 emulation mode, with
NetBSD/pmax as the guest operating system.

A couple of other emulation modes exist. Some of these modes are almost working
well enough to run complete guest operating systems, but most are just
skeletons. The modes that work are listed in the documentation.

The emulator can also be used in other experiments; it does not have to run
entire guest operating systems. (However, GXemul does not simulate things
smaller than an instruction. What this means is that pipe-line stalls,
penalties caused by branch-prediction misses or cache misses, and other
micro-architectural effects are not simulated.)

The user-visible changes between release 0.3.4 and 0.3.5 are minor, and
can be summarized as follows:

	o)  Updates to the (old) binary translation subsystem, resulting
	    in minor speed improvements.

	o)  64-bit MIPS dmult/dmultu has been fixed.

	o)  slt* instructions for 64-bit MIPS were incorrectly implemented
	    in the i386 backend. This has been fixed.

There have been many other bug fixes and updates, most of which are not 
visible.

Files included in this release are:

  BUGS                        A list of known bugs.
  HISTORY                     Detailed revision history / changelog.
  LICENSE                     Copyright message / license.
  README                      Quick start instructions, for the impatient.
  RELEASE                     This file.
  TODO                        TODO notes.
  configure, Makefile.skel    sh and make scripts for building GXemul.
  doc                         Documentation.
  experiments                 Experimental code. (Usually not needed.)
  src                         Source code.

To build the emulator, run the ./configure script, and then run make.

Building the emulator should work on most Unix-like systems. (One system which
is specifically known to NOT work is Ultrix/RISC inside the emulator; Ultrix
chokes on the configure script and the default cc in Ultrix doesn't work.)

Regarding files in the src/include/ directory: only some of these are written
by me, the rest are from other sources (such as NetBSD). The license text says
that "All advertising materials mentioning features or use of this software"
must display acknowledgements. Even though I do NOT feel I mention features or
use of the header files (the "software") in any advertising materials, I am
still very grateful for the fact that these people have made their files
available for re-use, so regardless of legal requirements, I guess thanking
them like this is in order:

    This product includes software developed by the University of
    California, Berkeley and its contributors.

    This product includes software developed for the
    NetBSD Project.  See http://www.netbsd.org/ for
    information about NetBSD.

    This product includes software developed by Jonathan Stone for
    the NetBSD Project.

    This product includes software developed for the NetBSD Project
    by Matthias Drochner.

    This product includes software developed by the NetBSD
    Foundation, Inc. and its contributors.

    This product includes software developed by Christopher G. Demetriou.
    [for the NetBSD Project.]

    This product includes software developed by Adam Glass.

    This product includes software developed by the PocketBSD project
    and its contributors.

    This product includes software developed by Peter Galbavy.

    Carnegie Mellon University   (multiple header files,
    no specific advertisement text required)

    This product includes software developed by Charles M. Hannum.

    This product includes software developed under OpenBSD by Per Fogelstrm.

    This product includes software developed by Per Fogelstrm.

    This product includes software developed at Ludd, University of
    Lule, Sweden and its contributors.

    This product includes software developed by Hellmuth Michaelis
    and Joerg Wunsch

    The font(s) in devices/fonts are Copyright (c) 1992, 1993, 1994
    by Hellmuth Michaelis and Joerg Wunsch.  ("This product includes software
    developed by Hellmuth Michaelis and Joerg Wunsch", well, the font
    is maybe not software, but still...)

    impactsr-bsd.h is Copyright (C) 2004 by Stanislaw Skowronek.

    This product includes software developed for the NetBSD Project by
    Wasabi Systems, Inc.  [by Simon Burge]

    arcbios_other.h is Copyright (c) 1996 M. Warner Losh.

    This product includes software developed by Marc Horowitz.

Also, src/include/alpha_rpb.h requires the following:

    Copyright (c) 1994, 1995, 1996 Carnegie-Mellon University.
    All rights reserved.

    Author: Keith Bostic, Chris G. Demetriou

    Permission to use, copy, modify and distribute this software and
    its documentation is hereby granted, provided that both the copyright
    notice and this permission notice appear in all copies of the
    software, derivative works or modified versions, and any portions
    thereof, and that both notices appear in supporting documentation.


See individual files for license details, if you plan to redistribute GXemul
or reuse code.

Thanks to (in no specific order) Joachim Buss, Juli Mallett, Juan RP, Alec
Voropay, Gran Weinholt, Alexander Yurchenko, and everyone else who has
provided me with feedback.

If you have found GXemul useful in some way, or feel like sending me comments
or feedback in general, then mail me at anders(at)gavare.se.

