gcc/ada/exp_disp.ads

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                         GNAT COMPILER COMPONENTS                         --
   4 --                                                                          --
   5 --                             E X P _ D I S P                              --
   6 --                                                                          --
   7 --                                 S p e c                                  --
   8 --                                                                          --
   9 --          Copyright (C) 1992-2005 Free Software Foundation, Inc.          --
  10 --                                                                          --
  11 -- GNAT is free software;  you can  redistribute it  and/or modify it under --
  12 -- terms of the  GNU General Public License as published  by the Free Soft- --
  13 -- ware  Foundation;  either version 2,  or (at your option) any later ver- --
  14 -- sion.  GNAT is distributed in the hope that it will be useful, but WITH- --
  15 -- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --
  16 -- or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License --
  17 -- for  more details.  You should have  received  a copy of the GNU General --
  18 -- Public License  distributed with GNAT;  see file COPYING.  If not, write --
  19 -- to  the  Free Software Foundation,  51  Franklin  Street,  Fifth  Floor, --
  20 -- Boston, MA 02110-1301, USA.                                              --
  21 --                                                                          --
  22 -- GNAT was originally developed  by the GNAT team at  New York University. --
  23 -- Extensive contributions were provided by Ada Core Technologies Inc.      --
  24 --                                                                          --
  25 ------------------------------------------------------------------------------
  26
  27 --  This package contains routines involved in tagged types and dynamic
  28 --  dispatching expansion.
  29
  30 with Types; use Types;
  31 package Exp_Disp is
  32
  33    --  Number of predefined primitive operations added by the Expander
  34    --  for a tagged type. If more predefined primitive operations are
  35    --  added, the following items must be changed:
  36
  37    --    Ada.Tags.Defailt_Prim_Op_Count    - indirect use
  38    --    Exp_Disp.Default_Prim_Op_Position - indirect use
  39    --    Exp_Disp.Set_All_DT_Position      - direct   use
  40
  41    Default_Prim_Op_Count : constant Int := 14;
  42
  43    type DT_Access_Action is
  44       (CW_Membership,
  45        IW_Membership,
  46        DT_Entry_Size,
  47        DT_Prologue_Size,
  48        Get_Access_Level,
  49        Get_Entry_Index,
  50        Get_External_Tag,
  51        Get_Prim_Op_Address,
  52        Get_Prim_Op_Kind,
  53        Get_RC_Offset,
  54        Get_Remotely_Callable,
  55        Inherit_DT,
  56        Inherit_TSD,
  57        Register_Interface_Tag,
  58        Register_Tag,
  59        Set_Access_Level,
  60        Set_Entry_Index,
  61        Set_Expanded_Name,
  62        Set_External_Tag,
  63        Set_Prim_Op_Address,
  64        Set_Prim_Op_Kind,
  65        Set_RC_Offset,
  66        Set_Remotely_Callable,
  67        Set_TSD,
  68        TSD_Entry_Size,
  69        TSD_Prologue_Size);
  70
  71    procedure Expand_Dispatching_Call (Call_Node : Node_Id);
  72    --  Expand the call to the operation through the dispatch table and perform
  73    --  the required tag checks when appropriate. For CPP types the call is
  74    --  done through the Vtable (tag checks are not relevant)
  75
  76    procedure Expand_Interface_Actuals    (Call_Node : Node_Id);
  77    --  Ada 2005 (AI-251): Displace all the actuals corresponding to class-wide
  78    --  interfaces to reference the interface tag of the actual object
  79
  80    procedure Expand_Interface_Conversion (N : Node_Id);
  81    --  Ada 2005 (AI-251): N is a type-conversion node. Reference the base of
  82    --  the object to give access to the interface tag associated with the
  83    --  secondary dispatch table
  84
  85    function Expand_Interface_Thunk
  86      (N           : Node_Id;
  87       Thunk_Alias : Node_Id;
  88       Thunk_Id    : Entity_Id;
  89       Thunk_Tag   : Entity_Id) return Node_Id;
  90    --  Ada 2005 (AI-251): When a tagged type implements abstract interfaces we
  91    --  generate additional subprograms (thunks) to have a layout compatible
  92    --  with the C++ ABI. The thunk modifies the value of the first actual of
  93    --  the call (that is, the pointer to the object) before transferring
  94    --  control to the target function.
  95
  96    function Fill_DT_Entry
  97      (Loc          : Source_Ptr;
  98       Prim         : Entity_Id) return Node_Id;
  99    --  Generate the code necessary to fill the appropriate entry of the
 100    --  dispatch table of Prim's controlling type with Prim's address.
 101
 102    function Fill_Secondary_DT_Entry
 103      (Loc          : Source_Ptr;
 104       Prim         : Entity_Id;
 105       Thunk_Id     : Entity_Id;
 106       Iface_DT_Ptr : Entity_Id) return Node_Id;
 107    --  (Ada 2005): Generate the code necessary to fill the appropriate entry of
 108    --  the secondary dispatch table of Prim's controlling type with Thunk_Id's
 109    --  address.
 110
 111    function Get_Remotely_Callable (Obj : Node_Id) return Node_Id;
 112    --  Return an expression that holds True if the object can be transmitted
 113    --  onto another partition according to E.4 (18)
 114
 115    function Init_Predefined_Interface_Primitives
 116      (Typ : Entity_Id) return List_Id;
 117    --  Ada 2005 (AI-251): Initialize the entries associated with predefined
 118    --  primitives in all the secondary dispatch tables of Typ.
 119
 120    procedure Make_Abstract_Interface_DT
 121      (AI_Tag          : Entity_Id;
 122       Acc_Disp_Tables : in out Elist_Id;
 123       Result          : out List_Id);
 124    --  Ada 2005 (AI-251): Expand the declarations for the secondary Dispatch
 125    --  Tables corresponding with an abstract interface. The reference to the
 126    --  dispatch table is appended at the end of Acc_Disp_Tables; it will be
 127    --  are later used to generate the corresponding initialization statement
 128    --  (see Exp_Ch3.Build_Init_Procedure).
 129
 130    function Make_DT_Access_Action
 131      (Typ    : Entity_Id;
 132       Action : DT_Access_Action;
 133       Args   : List_Id) return Node_Id;
 134    --  Generate a call to one of the Dispatch Table Access Subprograms defined
 135    --  in Ada.Tags or in Interfaces.Cpp
 136
 137    function Make_DT (Typ : Entity_Id) return List_Id;
 138    --  Expand the declarations for the Dispatch Table (or the Vtable in
 139    --  the case of type whose ancestor is a CPP_Class)
 140
 141    function Make_Disp_Asynchronous_Select_Body
 142      (Typ : Entity_Id) return Node_Id;
 143    --  Ada 2005 (AI-345): Generate the body of the primitive operation of type
 144    --  Typ used for dispatching in asynchronous selects.
 145
 146    function Make_Disp_Asynchronous_Select_Spec
 147      (Typ : Entity_Id) return Node_Id;
 148    --  Ada 2005 (AI-345): Generate the specification of the primitive operation
 149    --  of type Typ used for dispatching in asynchronous selects.
 150
 151    function Make_Disp_Conditional_Select_Body
 152      (Typ : Entity_Id) return Node_Id;
 153    --  Ada 2005 (AI-345): Generate the body of the primitive operation of type
 154    --  Typ used for dispatching in conditional selects.
 155
 156    function Make_Disp_Conditional_Select_Spec
 157      (Typ : Entity_Id) return Node_Id;
 158    --  Ada 2005 (AI-345): Generate the specification of the primitive operation
 159    --  of type Typ used for dispatching in conditional selects.
 160
 161    function Make_Disp_Get_Prim_Op_Kind_Body
 162      (Typ : Entity_Id) return Node_Id;
 163    --  Ada 2005 (AI-345): Generate the body of the primitive operation of type
 164    --  Typ used for retrieving the callable entity kind during dispatching in
 165    --  asynchronous selects.
 166
 167    function Make_Disp_Get_Prim_Op_Kind_Spec
 168      (Typ : Entity_Id) return Node_Id;
 169    --  Ada 2005 (AI-345): Generate the specification of the primitive operation
 170    --  of the type Typ use for retrieving the callable entity kind during
 171    --  dispatching in asynchronous selects.
 172
 173    function Make_Disp_Select_Tables
 174      (Typ : Entity_Id) return List_Id;
 175    --  Ada 2005 (AI-345): Populate the two auxiliary tables in the TSD of Typ
 176    --  used for dispatching in asynchronous, conditional and timed selects.
 177    --  Generate code to set the primitive operation kinds and entry indices
 178    --  of primitive operations and primitive wrappers.
 179
 180    function Make_Disp_Timed_Select_Body
 181      (Typ : Entity_Id) return Node_Id;
 182    --  Ada 2005 (AI-345): Generate the body of the primitive operation of type
 183    --  Typ used for dispatching in timed selects.
 184
 185    function Make_Disp_Timed_Select_Spec
 186      (Typ : Entity_Id) return Node_Id;
 187    --  Ada 2005 (AI-345): Generate the specification of the primitive operation
 188    --  of type Typ used for dispatching in timed selects.
 189
 190    procedure Set_All_DT_Position (Typ : Entity_Id);
 191    --  Set the DT_Position field for each primitive operation. In the CPP
 192    --  Class case check that no pragma CPP_Virtual is missing and that the
 193    --  DT_Position are coherent
 194
 195    procedure Set_Default_Constructor (Typ : Entity_Id);
 196    --  Typ is a CPP_Class type. Create the Init procedure of that type to
 197    --  be the default constructor (i.e. the function returning this type,
 198    --  having a pragma CPP_Constructor and no parameter)
 199
 200    procedure Write_DT (Typ : Entity_Id);
 201    pragma Export (Ada, Write_DT);
 202    --  Debugging procedure (to be called within gdb)
 203
 204 end Exp_Disp;