* double-int.h (HOST_BITS_PER_DOUBLE_INT): Define.
	(double_int_not, double_int_lshift, double_int_rshift): Declare.
	(double_int_negative_p): Convert to static inline function.
	* double-int.c (double_int_lshift, double_int_lshift): Add new function.
	(double_int_negative_p): Remove.
	* tree.h (lshift_double, rshift_double): 
	* tree.c (build_low_bits_mask): Clean up, use double_int_* functions.
	* fold-const.c (fold_convert_const_int_from_real,
	fold_convert_const_int_from_fixed, div_if_zero_remainder): (Ditto.).
	(lshift_double): Change type of arith argument to bool.
	(rshift_double): Change type of arith argument to bool. Correct
	comment.
	* expmed.c (mask_rtx, lshift_value): (Ditto.).

From-SVN: r158360