Move "(A & C) == D is false when D & ~C != 0" to match.pd

2017-05-25  Marc Glisse  <marc.glisse@inria.fr>

	* fold-const.c (fold_binary_loc) [(A & C) == D]: Remove transformation.
	* match.pd (X == C): Rewrite it here.
	(with_possible_nonzero_bits, with_possible_nonzero_bits2,
	with_certain_nonzero_bits2): New predicates.
	* tree-ssanames.c (get_nonzero_bits): Handle INTEGER_CST.

From-SVN: r248447