fold-const.c (fold_inf_compare): New function to simplify FP comparisons against +Infinity or -Infinity.


	* fold-const.c (fold_inf_compare):  New function to simplify FP
	comparisons against +Infinity or -Infinity.
	(fold):  Optimize floating point comparisons against Infs and NaNs.

	* gcc.c-torture/execute/ieee/fp-cmp-6.c: New test case.
	* gcc.c-torture/execute/ieee/fp-cmp-7.c: New test case.

From-SVN: r64945