Re: I found a FORTH stack optimzer, but could use a better version.

"Marcel Hendrix" <mhx@[EMAIL PROTECTED]
> wrote in message
news:02231217223559@[EMAIL PROTECTED]
> "Rod Pemberton" <do_not_have@[EMAIL PROTECTED]
> writes Re: I found a FORTH
stack optimzer, but could use a better version.
> [..]
> > Sorry, I wasn't using their optimizer for FORTH, although that's
> > (apparently) what it was written for.  My use is for a optimizing a
> > compiler, but it could be useful for a FORTH implementor to optimize
the
> > underlying assembly...
>
> In a Forth optimizing compiler, stack words (in almost all cases for
"sane"
> code) do not generate any code. Such words do not do any useful "work,"
they
> just reorder the stack for words that do, and instruction/address mode
selection
> will take care of it.
>

Well, they either have an allocator that keeps track of the adjusted
position of elements on the stack or they must manually move "cells"
around
on the stack, correct?

Let's see, Dr. CH Ting's eForth (36 primitives) has 11 stack operators as
primitives.  Mikael Patel's minimal FORTH machine (9 primitives) has 6
stack
operators as primitives.  Mark Hayes MRFORTH (23 primitives) has 6 stack
operators as primitives.  Koopman's high execution frequency list has 5
stack operators.  GNU GFORTH has (46 primitives) has 16 stack operators as
primitives.

I guess the old and simple ones aren't too "sane"...  :-)  Of course, they
aren't STC either but DTC or ITC.




Rod Pemberton