At 12:53 PM 8/7/2001 -0400, Sam Tregar wrote:
>On Mon, 6 Aug 2001, Dan Sugalski wrote:
>
> > No, he's right. Not dirtying cache lines is pretty much always faster than
> > dirtying them, and not twiddling with memory's faster than twiddling. And
> > unfortunately we can't really do fully platform-dependent code, since it'll
> > be the actual bytecode that'll ned to be different.
>
>Ok, I'll go back to lurking - I definitely don't have the education to try
>to argue the point. I've got some half-formed idea about a stack-based
>opcode set that compiles down to register references at runtime, but I'm
>definitely a few books short of articulate on this subject.
You can definitely go from a stack-based to register-based system--heck,
it's what perl does now, after a fashion. :) Doing it efficiently's a
different problem entirely, and it adds some extra inefficiencies to the
process. You get a sort of impedence mismatch problem when you switch
between stack & register forms, which you don't (as much) when going from
register to register forms.
>Choose wisely then - if we want this thing to run well on the Palm and on
>the Athlon we'll have to!
The Athlon's easy--we're in the "power to burn" category there. It's the
Palm that's trickier.
> > We're actually doing the appropriate amount of optimization here. When
> > dealing with low-level constructs it's appropriate to consider low-level
> > effects and algorithms that handle low-level machinery.
>
>Lo tho we walk through the valley of the shadow of the JVM... Is anyone
>else nervous that we seem to be trying to replace GCC here?
Me! Though being nervous is my job, I think.
>Is register
>allocation really something the Perl community has expertise in?
This is an old, solved problem. There's literature that predates me in this
arena. (Heck, I think there might be literature that predates Larry)
It's not something the perl community per se has really ever needed to deal
with, but that's because it's not really something that most communities
need to deal with. There aren't all that many folks seriously writing
compilers. (Whether this is a good thing or not is a separate issue)
Dan
--------------------------------------"it's like this"-------------------
Dan Sugalski even samurai
[EMAIL PROTECTED] have teddy bears and even
teddy bears get drunk
