* real.h (struct real_value): Use the same type for all
bitfields.  Rename exp to uexp.
(REAL_EXP, SET_REAL_EXP): New accessor macros for uexp.
Adjust all uses of exp...
* builtins.c: ... here, ...
* emit-rtl.c: ... here, and ...
* real.c: ... and here.

From-SVN: r79802