speeding up the simplifier



On 2/16/07, Robert Dodier <robert.dodier at gmail.com> wrote:
>
> On 2/16/07, Richard Fateman <fateman at cs.berkeley.edu> wrote:
>
> > It used to be that the operators  property came first on the property
> list
> > of symbols like %sin.
> > This made it faster for the simplifier to get to programs like
> simp-%sin.
>
> Maybe in some version of Lisp it made a difference. From
> what I can tell, it doesn't anymore.


You mean there are versions of Lisp which don't do a sequential search on
the property list?  The difference may be small, however....

So I don't see a point to
> trying to organize the property list. Also, this optimization assumes
> that a substantial fraction of the time spent by the simplifier is
> (GET 'FOO 'OPERATORS). I doubt if that's the case.


That is I think a better argument.  But these things add up.  We old-timers
like to see tight code.

                -s