globals as structure

Tim Rowledge tim at sumeru.stanford.edu
Wed Nov 20 22:33:22 UTC 2002


Marcel Weiher <marcel at metaobject.com> is claimed by the authorities to have written:

> By the way, couldn't passing the pointer to the interpreter struct to 
> each function be faster still?  After all, registers are probably 
> plentyful, and that would eliminate access to the global structure 
> pointer.  Of course, that would mean altering the signature of the C 
> functions.
It's likely to be very cpu specific - remember, x86s only have three (or
is it four, or five?) registers not already dedicated to something or
other. PPC has quite a few, ARM has a modest surplus, Alpha has a
gazillion etc etc. It's one of those details that one ought to be able
to leave to a compiler but can't really trust completely.

Notwithstanding that matter it would be nice to pass args etc to the
primitives in a 'normal' manner so that we could take advantage of the
cpus calling conventions properly.

tim

-- 
Tim Rowledge, tim at sumeru.stanford.edu, http://sumeru.stanford.edu/tim
"Bother," said Pooh, as he fell into the nitric acid bath.




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