GC.calloc with random bits causes slowdown, also seen in built in AA

[Michael Rynn]

> When there is such a drop in replacement, it will be easier for others
> to try it out in existing code and uncover quirks and limitations.  Then
> there might be benefits.

Committed a struct AA wrapper and a modified PyDict class in hash\pydict.d
as builtin AA behave-alike, to the DSource - aa project.

Actually the builtin is initially about 10% bit faster in uint[uint] than
the PyDict.  Based on the first few runs that is,  before progressive
slowdown of builtin takes affect.   Perhaps some crafty optimization could
narrow the gap a bit.

There appears to be no significant performance effect of wrapping the
modified PyDict class as an implementation reference inside the struct.


Back next week

--=taf

Michael.