Accepted & assigned back to Trent.
I sure hope MS supports a similar performance counter under Itanium soon!  time.clock under WinTel32 is one of Python's great Windows joys.

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Mark Hammond provided (a long time ago) a better Win32 specific time_clock
implementation in timemodule.c. The library for this implementation does not
exist on Win64 (yet, at least). This patch makes Win64 fall back on the
system's clock() function for time_clock().