Re: Compilation to native

[David Kastrup]

Matthew Mundell <address@hidden> writes:

> Richard Stallman <address@hidden> writes:
> 
> > Anyway, such a small speedup is not worth the trouble.
> > Compilation of CCL may be worth while.  Or optimization of the CCL
> > interpreter may be possible.
> 
> This is for the record, at least.  The speedup is a little better
> with Fgtr inlined into the native, a few excess memory instructions
> saved, and, where possible, objects passed between byte operations
> using registers instead of the stack.
> 
> Byte compiled:
>   ("Tue Mar 30 21:54:05 2004" "Tue Mar 30 21:54:21 2004")  16 s
>   ("Tue Mar 30 21:54:26 2004" "Tue Mar 30 21:54:42 2004")  16 s
>   ("Tue Mar 30 21:54:45 2004" "Tue Mar 30 21:55:01 2004")  16 s
> 
> Compiled from byte code to native:
>   ("Tue Mar 30 21:55:43 2004" "Tue Mar 30 21:55:49 2004")  6 s
>   ("Tue Mar 30 21:55:51 2004" "Tue Mar 30 21:55:58 2004")  7 s
>   ("Tue Mar 30 21:56:01 2004" "Tue Mar 30 21:56:07 2004")  6 s

This sounds impressive, but of course in real-life tasks the amount of
work done by the Lisp interpreter as opposed to C primitives should be
less.  One would have to see the memory impact as well to find out
whether the overall gains in processing speed would remain as
impressive.  One thing that is nice about the byte code is that it is
pretty hard to terminally crash the machine just with Lisp (yes, I am
aware that there are byte code sequences that can cause segfaults).

Perhaps a CVS branch for playing around with the concept some more
would be worthwhile?

-- 
David Kastrup, Kriemhildstr. 15, 44793 Bochum