[Python-3000] Where is PyUnicodeObject->hash supposed to be set?

[Nicholas Bastin]

Before I do a bunch of searching around in the source, perhaps someone
just knows the answer to this question.

A quick trip through the debugger indicates that the reason
PyDict_GetItem is being called 5 million times more often in
PyEval_EvalFrameEx in 3.0 (in pystone 100000) is because while
PyString_CheckExact was swapped out for PyUnicode_CheckExact in
LOAD_GLOBAL, ((PyUnicodeObject*)w)->hash always evaluates to -1, which
punts us down to the non-inline code.  Presumably
((PyStringObject*)w)->ob_shash was already set at this point, which is
why it worked in 2.6 and previous.

Before I spend a lot of time trying to track down where this is
supposed to be getting set (or, needs to be being set), does anyone
know where this is supposed to happen?

--
Nick