At 08:44 PM 11/7/2001 +0100, Bart Schuller wrote:
>On Wed, Nov 07, 2001 at 07:12:40AM -0600, Dave Goehrig wrote:
> > I brought up the whole low level integer rewrite stuff above, because
> > look at it again. That is eactly what we are meant to do when we know
> > it is safe to optimize a variable to a more limited domain than say
> > 'scalar'. We don't even go through the motions of vtables.
>
>I've been thinking of the same things. It's no use writing a good
>optimizer for a register machine if every variable you have could be
>magically tied and execute a redefinetheworld on read.
Believe me, the irony of designing an architecture that potentially allows
for a nice set of optimizations that runs languages that you can't optimize
has not been lost on me. :)
FWIW, most folks won't even know, since the current compile-and-go scheme
leaves very little time, by default, for optimization.
>So I'd hope there will be a way to say (at the Perl6 language level)
>that this variable $foo is really a plain int.
I'm hoping so as well.
>It's also important to know that there are no unforeseen aliases for a
>variable (like $bar = \$foo), but I don't know how one could specify
>that, if at all.
You can't, the best you can do is a lot of analysis on subroutines and
optimize in the few places you can. It makes optimization a lot more
expensive, since you need to do a lot of dataflow analysis and carry around
a lot of information on subroutines and things. It's doable, and a subset
of perl programs will be able to be aggressively optimized. How small that
subset is, of course, is up in the air.
Dan
--------------------------------------"it's like this"-------------------
Dan Sugalski even samurai
[EMAIL PROTECTED] have teddy bears and even
teddy bears get drunk
