simplify-rtx.c (simplify_binary_operation_1): Do not simplify IOR to a constant if one operand has side effects.

	* simplify-rtx.c (simplify_binary_operation_1): Do not simplify
	IOR to a constant if one operand has side effects.

testsuite:
	* gcc.c-torture/execute/20120808-1.c: New test.

From-SVN: r190237