Bug #:

Submitted by:
Reviewed by:
-Lot's of detail work in UsualArithmeticConversion(). Needed to expand
the code for dealing with floating types. This code still has a couple
of FIXME's and could be refactored a bit.
-Added a bunch of Type predicates to simplify the float conversions.
Used the opportunity to convert a bunch of predicates to dyn_cast (it's cleaner
when just dealing with Builtin types).

llvm-svn: 39412