match.pd: Implement more binary patterns exercised by fold_stmt.

2014-11-14  Richard Biener  <rguenther@suse.de>

	* match.pd: Implement more binary patterns exercised by
	fold_stmt.
	* fold-const.c (sing_bit_p): Export.
	(exact_inverse): Likewise.
	(fold_binary_loc): Remove patterns here.
	(tree_unary_nonnegative_warnv_p): Use CASE_CONVERT.
	* fold-const.h (sing_bit_p): Declare.
	(exact_inverse): Likewise.

	* gcc.c-torture/execute/shiftopt-1.c: XFAIL invalid parts.

From-SVN: r217545