flow.c (commit_one_edge_insertion): Be prepared for a return insn to be inserted on the edge with a normal jump.

        * flow.c (commit_one_edge_insertion): Be prepared for a return
        insn to be inserted on the edge with a normal jump.
        * jump.c (jump_optimize_1): Don't look to create return isns.

        * flow.c (flow_delete_insn): Don't adjust reference count of notes.
        * jump.c (jump_optimize_1): Likewise.
        (returnjump_p): Verify the argument is a JUMP_INSN.
        * rtl.def (NOTE): Add 5th element for NOTE_INSN_DELETED_LABEL.

From-SVN: r33950