* match.pd: New simplification patterns.
	(x + (x & 1))  -> ((x + 1) & ~1)
	(x & ~(x & y)) -> ((x & ~y))
	(x | ~(x | y)) -> ((x | ~y))

	* gcc.dg/20150120-1.c: New test.
	* gcc.dg/20150120-2.c: New test.
	* gcc.dg/20150120-3.c: New test.

From-SVN: r222697