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From: Gerry Jackson <do-not-use@swldwa.uk>
Newsgroups: comp.lang.forth
Subject: Re: Juggling system-compilation items
Date: Tue, 13 Aug 2024 20:31:00 +0100
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On 12/08/2024 10:45, albert@spenarnc.xs4all.nl wrote:
> In article<v9bdpm$2sbsi$1@dont-email.me>,
> Gerry Jackson<do-not-use@swldwa.uk>  wrote:
>> ISTM that using the data stack to hold the control stack is an
>> anachronism that was used in early Forth systems because of the limited
>> amount of memory available. I also think that the system should not get
>> in the way of user programs as putting control stack data on the data
>> stack certainly does.
> It alleviates restriction. Marcel Hendrix hated the restrictions of
> R> >R and added the socalled "system stack" S> >S that can be used
> over definitions. The disadvantage is of course that there are more
> regions of memory that you have to keep track of.
> I think that added complexity is a more important consideration as
> memory usage. The more stacks you have and the more stack items
> you keep in registers, the more difficult e.g. task switching becomes.

As use of a control stack is during compilation, speed is not too 
important so why would register(s) be used for it?

-- 
Gerry