Java instead of freedom - the best option?
Tom Thornhill
tthornhi@best.ms.philips.com
Tue, 6 May 1997 14:05:05 +0200
Bill House <bhouse@dazsi.nospam.com> wrote in article
<01bc5964$4f54f220$03d3c9d0@wjh_dell_133.dazsi.com>...
> Tom Thornhill <tthornhi@best.ms.philips.com> wrote in article
> <01bc5949$fabf0a80$725e9082@mniw1001>...
> >
> Well, you're obviously pretty well-versed in VM technology, 'cuz you've
just given a
> pretty good description of one of the VM architctures we're considering
for the UVM.<g>
I'm told TAOS did something very similar ( but I never managed to track
down the
specs ). So the proposed VM wil have a Mips like instruction set ( though
with stuff like
delayed branches removed ) that will get compiled on install / run. This
has the advantage
of being a very easy operation ( I reckon you could write a decent native
code generator for such an
architecture in a month or so - you could make all the branches in the VM
code through
arrays of function pointers which would be optimised out of the native
code, or something like that )
Actually there's probably a VM type that is better than imaginary Risc or
stack based
if you don't ever intend to interpret ( IMHO a good starting point ). Maybe
we should ask
Hennessy or Paterson what they think ;-). The real reason that I like VM's
is that they let people
experiment with processor design the way the currently experiment with
expansion cards. A truly
universal VM would let you run an application designed for an API ( whether
Java / Win32 / MFC / Unix )
written in any language run on any processor that the API has been ported
to. I think the problem with
Java is that the VM concept(good) gets bound up with a new and language and
class library(debatable).
> >
> > But a Microsoft VM would only support the Win32 API, Microsoft have no
> > interest in abstracting the user interface API.
> >
> Here is where the Java team has done a good job, even though it's a very
hard thing to
.....
> compelling reason to do otherwise. BTW, part of the UVM architecture is
being
> multi-lingual, so RTLs that target specific environments, like Win32, can
be easily
> added.
I'm not denying that Java is does a good job abstracting the user interface
-
I'm saying that it does too good a job from Microsoft's point of view. The
UVM should
let them continue to promote Win32 / MFC if they want to.
>
> Bill House
> --
> http://www.dazsi.com
> Note: my e-mail address has been altered to
> confuse the enemy. The views I express are
> mine alone (unless you agree with me).
>
>
PS - I've seen some references on the mailing list to "optimisation tables"
- any one care to
clarify post a FAQ / Spec to the list ( ditto for any Taos info ).
PPS - For god's sake no one tell the guys in comp.lang.asm.x86 about this!
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