Potential optimisation?

[Robert Viduya]

> 2)  In a UNIX C compiler (to the best of my knowledge) two assembly
> procedures CSV and CRET are used to save and restore the registers in
> the *called* procedure.  I fail to see why this is desirable.  The
> *calling* procedure has full knowledge of which registers are being
> used and can save them itself.  This may not result in savings, but I
> don't see where it can result in a performance degradation.
> 

Then there's the Pyramid 90x machines where the registers (at least 32 of
them) are 'saved' (not really 'saved', more like 'pushed down') by the
machine itself without the need of special assembly procedures.  But that
topic was discussed a few months ago.


				robert
-- 
Robert Viduya
    Office of Computing Services
    Georgia Institute of Technology, Atlanta GA 30332
    Phone:  (404) 894-4669

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