einfo.ads, einfo.adb (Static_Real_Or_String_Predicate): New function

einfo.ads, einfo.adb (Static_Real_Or_String_Predicate): New function

2014-07-29  Robert Dewar  <dewar@adacore.com>

	* einfo.ads, einfo.adb (Static_Real_Or_String_Predicate): New function
	(Set_Static_Real_Or_String_Predicate): New procedure
	* sem_ch13.adb (Build_Predicate_Functions): Accomodate static
	string predicates (Is_Predicate_Static): Handle static string
	predicates.
	* sem_eval.adb (Real_Or_String_Static_Predicate_Matches):
	New procedure (Check_Expression_Against_Static_Predicate):
	Deal with static string predicates, now fully implemented
	(Eval_Relational_Op): Allow string equality/inequality as static
	if not comes from source.

From-SVN: r213162