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From: minforth <minforth@gmx.net>
Newsgroups: comp.lang.forth
Subject: Re: OOS approach revisited
Date: Fri, 27 Jun 2025 11:49:11 +0200
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Am 27.06.2025 um 09:29 schrieb dxf:
> On 27/06/2025 12:16 pm, minforth wrote:
>> ...
>> IIRC DO..LOOPs had been a hack for computers in the 60s.
>> A rather ugly hack, born out of necessity, slow and
>> often cumbersome to use. That it still persists in Forth
>> half a century later speaks for Forth's progressiveness.
> 
> Testing FOR NEXT on my DTC system showed 15% speed increase over
> DO LOOP.  Putting 5 NOOPs (executes forth's address interpreter)
> in the innermost loop brought it down to 6%.  Not worth it IMO.
> 

It really depends on how counted loops are implemented.
Most CPUs have operators for register-based count-down loops
that are blazingly fast.

If they can be used within Forth-based loop constructs
I would expect a greater speed increase than what you measured.