------------------------------------------------------------------------------
--                                                                          --
--                         GNAT COMPILER COMPONENTS                         --
--                                                                          --
--                              E X P _ C H 3                               --
--                                                                          --
--                                 S p e c                                  --
--                                                                          --
--          Copyright (C) 1992-2007, Free Software Foundation, Inc.         --
--                                                                          --
-- GNAT is free software;  you can  redistribute it  and/or modify it under --
-- terms of the  GNU General Public License as published  by the Free Soft- --
-- ware  Foundation;  either version 3,  or (at your option) any later ver- --
-- sion.  GNAT is distributed in the hope that it will be useful, but WITH- --
-- OUT 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 GNAT; see file COPYING3.  If not, go to --
-- http://www.gnu.org/licenses for a complete copy of the license.          --
--                                                                          --
-- GNAT was originally developed  by the GNAT team at  New York University. --
-- Extensive contributions were provided by Ada Core Technologies Inc.      --
--                                                                          --
------------------------------------------------------------------------------

--  Expand routines for chapter 3 constructs

with Types;  use Types;
with Elists; use Elists;
with Uintp;  use Uintp;

package Exp_Ch3 is

   procedure Expand_N_Object_Declaration         (N : Node_Id);
   procedure Expand_N_Subtype_Indication         (N : Node_Id);
   procedure Expand_N_Variant_Part               (N : Node_Id);
   procedure Expand_N_Full_Type_Declaration      (N : Node_Id);

   procedure Expand_Previous_Access_Type (Def_Id : Entity_Id);
   --  For a full type declaration that contains tasks, or that is a task,
   --  check whether there exists an access type whose designated type is an
   --  incomplete declarations for the current composite type. If so, build the
   --  master for that access type, now that it is known to denote an object
   --  with tasks.

   procedure Expand_Record_Extension (T : Entity_Id; Def : Node_Id);
   --  Add a field _parent in the extension part of the record

   procedure Build_Class_Wide_Master (T : Entity_Id);
   --  For access to class-wide limited types we must build a task master
   --  because some subsequent extension may add a task component. To avoid
   --  bringing in the tasking run-time whenever an access-to-class-wide
   --  limited type is used, we use the soft-link mechanism and add a level of
   --  indirection to calls to routines that manipulate Master_Ids. This must
   --  also be used for anonymous access types whose designated type is a task
   --  or synchronized interface.

   procedure Build_Discr_Checking_Funcs (N : Node_Id);
   --  Builds function which checks whether the component name is consistent
   --  with the current discriminants. N is the full type declaration node,
   --  and the discriminant checking functions are inserted after this node.

   function Build_Initialization_Call
     (Loc               : Source_Ptr;
      Id_Ref            : Node_Id;
      Typ               : Entity_Id;
      In_Init_Proc      : Boolean := False;
      Enclos_Type       : Entity_Id := Empty;
      Discr_Map         : Elist_Id := New_Elmt_List;
      With_Default_Init : Boolean := False) return List_Id;
   --  Builds a call to the initialization procedure for the base type of Typ,
   --  passing it the object denoted by Id_Ref, plus additional parameters as
   --  appropriate for the type (the _Master, for task types, for example).
   --  Loc is the source location for the constructed tree. In_Init_Proc has
   --  to be set to True when the call is itself in an init proc in order to
   --  enable the use of discriminals. Enclos_Type is the enclosing type when
   --  initializing a component in an outer init proc, and it is used for
   --  various expansion cases including the case where Typ is a task type
   --  which is an array component, the indices of the enclosing type are
   --  used to build the string that identifies each task at runtime.
   --
   --  Discr_Map is used to replace discriminants by their discriminals in
   --  expressions used to constrain record components. In the presence of
   --  entry families bounded by discriminants, protected type discriminants
   --  can appear within expressions in array bounds (not as stand-alone
   --  identifiers) and a general replacement is necessary.
   --
   --  Ada 2005 (AI-287): With_Default_Init is used to indicate that the
   --  initialization call corresponds to a default initialized component
   --  of an aggregate.

   procedure Build_Master_Renaming (N : Node_Id; T : Entity_Id);
   --  If the designated type of an access type is a task type or contains
   --  tasks, we make sure that a _Master variable is declared in the current
   --  scope, and then declare a renaming for it:
   --
   --    atypeM : Master_Id renames _Master;
   --
   --  where atyp is the name of the access type. This declaration is
   --  used when an allocator for the access type is expanded. The node N
   --  is the full declaration of the designated type that contains tasks.
   --  The renaming declaration is inserted before N, and after the Master
   --  declaration.

   function Freeze_Type (N : Node_Id) return Boolean;
   --  This function executes the freezing actions associated with the given
   --  freeze type node N and returns True if the node is to be deleted. We
   --  delete the node if it is present just for front end purpose and we don't
   --  want Gigi to see the node. This function can't delete the node itself
   --  since it would confuse any remaining processing of the freeze node.

   procedure Init_Secondary_Tags
     (Typ            : Entity_Id;
      Target         : Node_Id;
      Stmts_List     : List_Id;
      Fixed_Comps    : Boolean := True;
      Variable_Comps : Boolean := True);
   --  Ada 2005 (AI-251): Initialize the tags of the secondary dispatch tables
   --  of Typ. The generated code referencing tag fields of Target is appended
   --  to Stmts_List. If Fixed_Comps is True then the tag components located at
   --  fixed positions of Target are initialized; if Variable_Comps is True
   --  then tags components located at variable positions of Target are
   --  initialized.

   function Needs_Simple_Initialization (T : Entity_Id) return Boolean;
   --  Certain types need initialization even though there is no specific
   --  initialization routine. In this category are access types (which need
   --  initializing to null), packed array types whose implementation is a
   --  modular type, and all scalar types if Normalize_Scalars is set, as well
   --  as private types whose underlying type is present and meets any of these
   --  criteria. Finally, descendants of String and Wide_String also need
   --  initialization in Initialize/Normalize_Scalars mode.

   function Get_Simple_Init_Val
     (T    : Entity_Id;
      Loc  : Source_Ptr;
      Size : Uint := No_Uint) return Node_Id;
   --  For a type which Needs_Simple_Initialization (see above), prepares the
   --  tree for an expression representing the required initial value. Loc is
   --  the source location used in constructing this tree which is returned as
   --  the result of the call. The Size parameter indicates the target size of
   --  the object if it is known (indicated by a value that is not No_Uint and
   --  is greater than zero). If Size is not given (Size set to No_Uint, or
   --  non-positive), then the Esize of T is used as an estimate of the Size.
   --  The object size is needed to prepare a known invalid value for use by
   --  Normalize_Scalars.

end Exp_Ch3;