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Re: MCL for PowerPC?

Hello everybody,

> In his article, Karsten Poeck writes:
>% What's the future direction for MCL?
>Apple is continuing to enhance and support MCL. A maintenance release, MCL
>2.01, will be available shortly, primarily to extend MCL support to the
>latest Macintosh machines, such as the Centris 610, the Centris 660av, and
>the Quadra 840av.
>We are currently planning future releases of MCL to provide a variety of
>enhancements, including PowerPC support. We have not announced future
>products at this time.
>--------- End quote
>This is not really a promise and makes me a little bit nervous about the
>future of MCL, since the PowerPC may totally replace the 68Kmacs in the
>Karsten Poeck

I'm not an expert in MCL implementation nor in PowerPC usage, but I think
that porting MCL to powerPC is not really an easy thing.

As MCL is implemented it converts LISP into a pseudo-code close to 680x0
assembley language and interprets it (correct me if I'm wrong).

The crucial part of MCL is its interpreter. But porting it under PowerPC
will make it much more complex as it will interpret a 68k like code under
PowerPC (sounds like an interpreter no?).

What will really be the gained speed?

I think that the Lisp compilation should be changed and should generate a
different pseudo-code that will take advantage on the new PowerPC RISK
architecture. And this is much more difficult.

Hey, Lisp gurus, could you tell me if this is true or false ?

However, MCL can be used as is on a PowerPC, but you will lose speed
(perhaps) and make your PowerPC machine a slow as a LCIII (in the worst
case). But you could win depending on the toolbox you use the most.

Has anybody more information on that ?


 Il ne suffit pas d'etre heureux. Encore faut-il que
 les autres soient malheureux.          P. Desproges
-----  Gilles.Serasset@imag.fr (Gilles Serasset)  ----