PEP 266: Optimizing Global Variable/Attribute Access

[Skip Montanaro]

    Peter> Hello Python Optimizers  :-)
    Peter> After reading PEP 266, I coded the following:

    [ ... snip tests ... ]

    Peter> So it seems that *without* the execution of the proposed
    Peter> TRACK_OBJECT and UNTRACK_OBJECT there would be about a 31%
    Peter> improvement.  Unless I'm missing something fundamental, if the
    Peter> compiler can be made smart enough to know where to put
    Peter> TRACK_OBJECT and UNTRACK_OBJECT then why can't it do the code
    Peter> transformation as above?

That's the plan.  ;-) 

Actually, if I do it right, PEPTest2 would work more like

    def PEPTest2():
        m = math.sin
        c = 100000
        while c:
            l = []
            f = l.append
            for i in range(10):
                f(m(i))
            c -= 1

That is, math.sin would get cached at the earliest point where it is in
scope, which would be before the while loop.

-- 
Skip Montanaro (skip at pobox.com)
http://www.mojam.com/
http://www.musi-cal.com/