re PR middle-end/24427 (missing optimization opportunity with binary operators)

re PR middle-end/24427 (missing optimization opportunity with binary operators)

	PR middle-end/24427
	* fold-const.c (fold_binary) <BIT_IOR_EXPR>: Transform (X&C1)|C2
	into (X,C2) if C1 is a subset of the bits of C2.  Transform
	(X&C1)|C2 into X|C2 if C1|C2 == ~0.  Canonicalize (X&C1)|C2 as
	(X&(C1&~C2))|C2.
	<BIT_AND_EXPR>: Canonicalize (X|C1)&C2 as (X&C2)|(C1&C2).

	* gcc.dg/tree-ssa/andor-1.c: New test case.

From-SVN: r110918