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

Marcel Hendrix wrote:
> "Rod Pemberton" <do_not_have@[EMAIL PROTECTED]
> writes Re: I found a FORTH
stack optimzer, but could use a better version.
> [..]
[..]
> 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. 
> 
> The algorithm might be useful for a hardware stack engine (although I
would 
> hope that such chips don't do e.g. "SWAP +" as two separate operations).

Did you perhaps mean "SWAP -" ?   because "SWAP +" should always be 
reduced to one instruction!

In one particular type of stack engine "SWAP +" could be an 
optimisation to reduce the number of clock cycles used to complete 
the "+" instruction.

I mention this only in the spirit of the old adage: 'the exception 
proves the rule'  I assume that the word 'proves' here means to 
'demonstrate the limits of' or similar.

Jan Coombs