ifcvt.c (cheap_bb_rtx_cost_p): Add SCALE argument.

	* ifcvt.c (cheap_bb_rtx_cost_p): Add SCALE argument.  Scale
	non-jumping insns by REG_BR_PROB_BASE and the maximum cost
	by SCALE.
	(find_if_case_1): Use the probability of the THEN clause when
	determining if speculation is profitable.
	(find_if_case_2): Similarly for the ELSE clause.

From-SVN: r179284