* flow.c (mark_set_1, attempt_auto_inc, mark_used_reg,
	try_pre_increment_1): compute REG_FREQ using bb->frequency.

	* regclass.c (loop_cost): Kill.
	(frequency): New global variable.
	(record_operand_costs): Replace loop_cost by frequency.
	(scan_one_insn): Likewise.
	(regclass): Likewise; set frequency according to bb->frequency.

	* flow.c (split_edge): Set frequency.

From-SVN: r43523