Trim whitespace.

Trim whitespace.
Support cast of ints (and narrower) to float and double.
Support cast double to double (using load and store).
Abort if we see a CallInst or SetCondInst with long/fp args, instead
of producing bad code.
Support add, sub, mul, div of float and double.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@14440 91177308-0d34-0410-b5e6-96231b3b80d8