[34S] Proposal for Entry RPN mode with dynamic stack

[Paul Dale]

(02-15-2015 11:38 PM)Bit Wrote:  

(02-15-2015 11:07 PM)matthiaspaul Wrote:  Sure, but I was living under the impression that we are limited to 64 flags for some reasons. If we can extend UState beyond that, things would certainly become easier (also in other areas).

As far as I can see, you'd need to sacrifice something in order to increase the number of internal flags. Some of the user flags would be an obvious choice as there are way more of them than most people would ever need.

Yes, we're limited to 64 bits of system flags -- this is the size of a long long integer. Extending this will steal memory from something else. Pretty much everything is a trade off at this point.

We've deliberately avoided using (the numbered) user flags for system things. They are the user's and not ours.


A dynamic stack could exist in in the program/stack space with some shuffling instead of consuming registers directly. A user can always increase the free space here by reducing the number of registers.


Personally, I'd like to lose the weird stack lift behaviour in favour of something more consistent...


Pauli