expmed.c (choose_mult_variant): Pass MULT_COST as argument instead of using register...

expmed.c (choose_mult_variant): Pass MULT_COST as argument instead of using register multiplication cost.

	* expmed.c (choose_mult_variant): Pass MULT_COST as argument instead
	of using register multiplication cost.
	(expand_mult): Adapt choose_mult_variant call.
	(expand_mult_highpart): Call choose_mult_variant with WIDER_MODE
	of MODE; pass appropriate cost bound.  Adjust result when
	performing signed multiplication by a negative constant.
	Don't use intermediate modes larger than word_mode.

From-SVN: r79792