haifa-sched.c (build_control_flow): Accept raw data as inputs instead of computing...

haifa-sched.c (build_control_flow): Accept raw data as inputs instead of computing it locally.

        * haifa-sched.c (build_control_flow): Accept raw data as inputs
        instead of computing it locally.  Callers changed.
        (find_rgns): Several new arguments.  Callers changed.
        Generally clean up and comment better.  Use dominators to
        identify reducible loops.  Convert some flag arrays to bitmaps.
        Convert most of the code to work on pred/succ lists instead of
        an edge table.  Add comments for future improvements.
        (schedule_insns): Allocate temporary tables for flow data, call
        routines to compute flow data and pass it along to children as
        arguments.
        (debug_control_flow): Delete.  Use dump_bb_data instead.
General cleanup + fix a bug or two.

From-SVN: r19244