Re: porting?

[Dancer <dancer@brisnet.org.au>]

Maurits van de Kamp wrote:

> On Mon, 26 Jan 1998, Howard Chu wrote:
>
> > No, the Java runtime is not built in to Netscape. You have to get that
> > from Microsoft or Apple, on PCs and Macs. For Atari, you'll just have to
> > write it...
>
> Java-VM sources are freely available from SUN for anyone who wants to
> recompile them AFIK.. problem is, it would be terribly slow on an 8/16MHz
> Atari so it needs loads of optimisation (same goes for Netscape btw, I saw
> it running on a 386sx16 once and CAB suddenly didn't seem all that
> slow..:) )

Actually, the Java VM only needs one optimisation to run well at those speeds:
There's a 240-case switch statement in the main interpreter loop. Convert it
to a jump table, and you gain _two_orders_of_magnitude speed increase.

> Craig Graham has done all these optimisations and came up with a VM that
> will actually run on 16MHz at a usable speed (or at least so he says) but
> unfortunately the company he works for owns the copyrights to his work.
>
> Anyway, it doesn't need to be written, just get some of the lameness out
> of it (like replacing all the compare/jump-if-zero 's (which apparantly
> are used to lookup the command codes) by table lookups.

Err, yeah. Like I said.

That'll teach me not to read down to the bottom before I start replying, huh?

D


--
Did you read the documentation AND the FAQ?
If not, I'll probably still answer your question, but my patience will
be limited, and you take the risk of sarcasm and ridicule.