* General PCL cleanups:
-- Get rid of FUNCTION-FUNCALL and FUNCTION-APPLY: instead just
declare the argument type. ETOOMANYLAYERSOFABSTRACTION.
-- Implement the unused GET-FUN in terms of GET-FUN1 for clarity.
* Use a single bitmask instead of multiply and mask to compute the
cache index (like the original implementation).
* Slower probe depth limit growth: caches with 1024 lines used to
have probe depth 16, which is starting to be on the slow side, and
some fairly common generics like PRINT-OBJECT have caches with
enough entries that they will be large no matter what. Instead of
(ceiling (sqrt lines) 2) make it (ceiling (sqrt (sqrt lines))).
* Better CACHE-HAS-INVALID-ENTRIES-P (does less work, picks up
* MAP-ALL-CACHES and CHECK-CACHE-CONSISTENCY for debugging and
* Typo in the format string in PRINT-OBJECT (CACHE T).
* A couple of non-CLOS optimization possibilities recorded.