------------------------------------------------------------------------------
--                                                                          --
--                           OCARINA COMPONENTS                             --
--                                                                          --
--                 OCARINA.CHECKER.QUERIES.CALL_PREDICATES                  --
--                                                                          --
--                                 B o d y                                  --
--                                                                          --
--                 Copyright (C) 2007, GET-Telecom Paris.                   --
--                                                                          --
-- Ocarina  is free software;  you  can  redistribute  it and/or  modify    --
-- it under terms of the GNU General Public License as published by the     --
-- Free Software Foundation; either version 2, or (at your option) any      --
-- later version. Ocarina is distributed  in  the  hope  that it will be    --
-- useful, but WITHOUT ANY WARRANTY;  without even the implied warranty of  --
-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General --
-- Public License for more details. You should have received  a copy of the --
-- GNU General Public License distributed with Ocarina; see file COPYING.   --
-- If not, write to the Free Software Foundation, 51 Franklin Street, Fifth --
-- Floor, Boston, MA 02111-1301, USA.                                       --
--                                                                          --
-- As a special exception,  if other files  instantiate  generics from this --
-- unit, or you link  this unit with other files  to produce an executable, --
-- this  unit  does not  by itself cause  the resulting  executable to be   --
-- covered  by the  GNU  General  Public  License. This exception does not  --
-- however invalidate  any other reasons why the executable file might be   --
-- covered by the GNU Public License.                                       --
--                                                                          --
--                 Ocarina is maintained by the Ocarina team                --
--                       (ocarina-users@listes.enst.fr)                     --
--                                                                          --
------------------------------------------------------------------------------

with Ocarina.Nodes;
with Ocarina.Nutils; use Ocarina.Nutils;

package body Ocarina.Checker.Queries.Call_Predicates is
   use Types;
   use Ocarina.Nodes;

   package ONU renames Ocarina.Nutils;

   -------------------------
   -- Is_Called_Predicate --
   -------------------------

   function Is_Called_Predicate
     (E      : Node_Id;
      D      : Node_Id;
      Option : Predicates_Search_Options := PSO_Direct)
     return Boolean
   is
      function Find_Called_Subprograms
        (E : Node_Id)
        return Result_Set;

      -----------------------------
      -- Find_Called_Subprograms --
      -----------------------------

      function Find_Called_Subprograms
        (E : Node_Id)
        return Result_Set
      is
         Set : Result_Set;
      begin
         if E /= No_Node and then
           not ONU.Is_Empty (Calls (E)) then
            declare
               Call_Seq : Node_Id := First_Node (Calls (E));
               N        : Node_Id;
            begin
               while Present (Call_Seq) loop
                  if not ONU.Is_Empty (Subprogram_Calls (Call_Seq)) then
                     N := First_Node (Subprogram_Calls (Call_Seq));
                     while Present (N) loop
                        Add (Set, Corresponding_Declaration
                             (Corresponding_Instance (N)));
                        N := Next_Node (N);
                     end loop;
                     Call_Seq := Next_Node (Call_Seq);
                  end if;
               end loop;
            end;
         end if;

         return Set;
      end Find_Called_Subprograms;

      Direct_Calls_Set : Result_Set;
      Final_Set        : Result_Set := Empty_Set;
   begin
      Direct_Calls_Set := Find_Called_Subprograms (D);

      if Option = PSO_Direct then

         --  Returns true if the current node is a called by
         --  the parameter component...

         return Is_In (Corresponding_Declaration (E), Direct_Calls_Set);

      else
         --  Search called subprograms by generations

         --  Note that the fact we don't use 'distinct' option
         --  in unions allows us to search for recursive loops
         --  in subprograms calls.

         declare
            Tmp_Set : Result_Set;
         begin

            while not Is_Empty (Direct_Calls_Set)  loop

               for I in 1 .. Cardinal (Direct_Calls_Set) loop
                  Tmp_Set := Find_Called_Subprograms
                    (Corresponding_Instance (Get (Direct_Calls_Set, I)));
                  Direct_Calls_Set := Union (Tmp_Set, Direct_Calls_Set);
               end loop;

               Final_Set := Union (Final_Set, Direct_Calls_Set);

               Direct_Calls_Set := Empty_Set;
            end loop;
         end;

         return Is_In (E, Final_Set);
      end if;

   end Is_Called_Predicate;

end Ocarina.Checker.Queries.Call_Predicates;