Subject: Re: VAX 6400 booting saga: SUCCESS!
To: Gunther Schadow <>
From: Johnny Billquist <>
List: port-vax
Date: 03/17/2002 23:19:32
On Sun, 17 Mar 2002, Gunther Schadow wrote:

> Johnny Billquist wrote:
> > Start writing your own ieee floating point package then.
> Hmm, I don't really care for retaining the exact floating point
> semantics of Java, and I have read a paper from a floating
> point "expert" who was doubtful if an absolute same floating
> point semantics everywhere was even good or necessary. In fact
> the fun would be to use as many VAXisms as possible to get
> some decent speed out of it. The idea earlier was to actually
> supply microcode hacks (which one could do on an 86x0 (and
> probably a 11/78x (?))

Well, since the ieee and VAX fp binary formats don't agree you cannot
escape writing some ieee-handling stuff. Java is a virtual machine, where
the fp format is defined down to the bit. You'll atleast have to convert
to and from ieee for every fp op you do.


Johnny Billquist                  || "I'm on a bus
                                  ||  on a psychedelic trip
email:           ||  Reading murder books
pdp is alive!                     ||  tryin' to stay hip" - B. Idol