Date   : Mon, 27 Jul 1998 16:43:16 +0100
From   : David Alan Gilbert <dg@...>
Subject: Re: Acorn Achemedes

Hi,
  I have just uploaded version 0.40 of 'arcem'; the Archimedes
emulator for Unix systems.  Its main advantage over previous versions is

>>> A MASSIVE SPEEDUP <<<

(sorry for shouting...) - thats about 3 times speedup over version-0.10
- that makes it actually usable on a fast machine (like my Alpha).

As always I'd like to repeat that its >amazing< what will run on this
emulator.

You can find it on:

ftp://ftp.compsoc.man.ac.uk/pub/arcem/version-0.40

(Apologies for problems on that site a few weeks ago - they were
caused by some nasty hacker).

Included with the program is a binary disc image for ARM Linux
and a binary ROM image of ARM Linux, thus you can run ARM Linux
in an X window under another Unix system.

This version has been tested on my Alpha running Linux; on this 533MHz
machine it has hit over 3 million emulated cycles per second.
(Still someway to go - but its getting better!). Note that on
this a ROM cycle counts the same as a RAM cycle and sequential and
non-sequential cycles both count as 1.  So effectivly your A4x0 ran
at about 4MHz out of ROM - so its not far off that for things in ROM;
although of course the Linux stuff will come mainly out of RAM
(ecept for the initial load).

The speedups have been accomplished by heavy use of 'gprof' to find
out where the time was going and rewriting parts of it and stripping
loads of stuff out of the core ARM emulator - further speedups are
going to prove more challenging since most of the emulator time
is now spent in the core emulator; but I have a few ideas.

Enjoy,

Dave
-- 
- Dr. David Alan Gilbert - WARNING! This is a beta release .signature-
- Work:    dg @ cogency.co.uk        - +44-(0)161-428-9444           -
- Home:    gro.gilbert @ treblig.org -                               -