PR rtl-optimization/63340 (part 1)

PR rtl-optimization/63340 (part 1)

gcc/
	PR rtl-optimization/63340 (part 1)
	* ira-costs.c (all_cost_classes): New variable.
	(complete_cost_classes): New function, split out from...
	(setup_cost_classes): ...here.
	(initiate_regno_cost_classes): Set up all_cost_classes.
	(restrict_cost_classes): New function.
	(setup_regno_cost_classes_by_aclass): Restrict the cost classes to
	registers that are valid for the register's mode.
	(setup_regno_cost_classes_by_mode): Model the mode cache as a
	restriction of all_cost_classes to a particular mode.
	(print_allocno_costs): Remove contains_reg_of_mode check.
	(print_pseudo_costs, find_costs_and_classes): Likewise.

From-SVN: r216828