Use predicates for RTL objects

[Jakub Jelinek]

On Thu, Aug 08, 2019 at 10:42:06AM -0600, Jeff Law wrote:
> >>>> -/* Predicate yielding true iff X is an rtx for a double-int.  */
> >>>> +/* Predicate yielding true iff X is an rtx for a floating point constant.  */
> >>>>  #define CONST_DOUBLE_AS_FLOAT_P(X) \
> >>>>    (GET_CODE (X) == CONST_DOUBLE && GET_MODE (X) != VOIDmode)
> >>>
> >>> Is const_double really only used for floating point these days?

No.  But it is used for integers only if it has VOIDmode, so I
think the above comment change is fine.
CONST_DOUBLE isn't used for integers on targets that define
TARGET_SUPPORTS_WIDE_INT, but that is a minority of targets (though, the
most common ones).

	Jakub