anchor.diff:  init_work(State) ->
     %% Labels = hipe_icode_cfg:reverse_postorder(state__cfg(State)),
     Labels = [hipe_icode_cfg:start_label(state__cfg(State))],
  -  {Labels, [], sets:from_list(Labels)}.
  +  {Labels, [], set_from_list(Labels)}.
   
   get_work({[Label|Left], List, Set}) ->
  -  NewWork = {Left, List, sets:del_element(Label, Set)},
  +  NewWork = {Left, List, maps:remove(Label, Set)},
     {Label, NewWork};
   get_work({[], [], _Set}) ->
     fixpoint;
  
positive.code: -type final_fun() :: fun((mfa(), [range()]) -> 'ok').
  -type data() :: {mfa(), args_fun(), call_fun(), final_fun()}.
  -type label() :: non_neg_integer().
  -type info() :: gb_trees:tree().
  -type work_list() :: {[label()], [label()], sets:set()}.
  -type variable() :: #icode_variable{}.
  -type annotated_variable() :: #icode_variable{}.
  -type argument() :: #icode_const{} | variable().
  
negative.code:   state__info(S, {Label, in}).
  
  state__info(#state{info_map=IM}, Key) ->
    maps:get(Key, IM).
  
  state__update_info(State, LabelInfo, Rewrite) ->
    update_info(LabelInfo, State, [], Rewrite).
  