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|
------------------------------------------------------------------------------
-- --
-- GNAT RUN-TIME COMPONENTS --
-- --
-- A D A . T A G S --
-- --
-- B o d y --
-- --
-- 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 2, 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 COPYING. If not, write --
-- to the Free Software Foundation, 51 Franklin Street, Fifth Floor, --
-- Boston, MA 02110-1301, 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. --
-- --
-- GNAT was originally developed by the GNAT team at New York University. --
-- Extensive contributions were provided by Ada Core Technologies Inc. --
-- --
------------------------------------------------------------------------------
with Ada.Exceptions;
with System.HTable;
with System.Storage_Elements; use System.Storage_Elements;
with System.WCh_Con; use System.WCh_Con;
with System.WCh_StW; use System.WCh_StW;
pragma Elaborate_All (System.HTable);
package body Ada.Tags is
-----------------------
-- Local Subprograms --
-----------------------
function CW_Membership (Obj_Tag : Tag; Typ_Tag : Tag) return Boolean;
-- Given the tag of an object and the tag associated to a type, return
-- true if Obj is in Typ'Class.
function Get_External_Tag (T : Tag) return System.Address;
-- Returns address of a null terminated string containing the external name
function Is_Primary_DT (T : Tag) return Boolean;
-- Given a tag returns True if it has the signature of a primary dispatch
-- table. This is Inline_Always since it is called from other Inline_
-- Always subprograms where we want no out of line code to be generated.
function Length (Str : Cstring_Ptr) return Natural;
-- Length of string represented by the given pointer (treating the string
-- as a C-style string, which is Nul terminated).
function OSD (T : Tag) return Object_Specific_Data_Ptr;
-- Ada 2005 (AI-251): Given a pointer T to a secondary dispatch table,
-- retrieve the address of the record containing the Object Specific
-- Data table.
function SSD (T : Tag) return Select_Specific_Data_Ptr;
-- Ada 2005 (AI-251): Given a pointer T to a dispatch Table, retrieves the
-- address of the record containing the Select Specific Data in T's TSD.
pragma Inline_Always (CW_Membership);
pragma Inline_Always (Get_External_Tag);
pragma Inline_Always (Is_Primary_DT);
pragma Inline_Always (OSD);
pragma Inline_Always (SSD);
---------------------------------------------
-- Unchecked Conversions for String Fields --
---------------------------------------------
function To_Address is
new Unchecked_Conversion (Cstring_Ptr, System.Address);
function To_Cstring_Ptr is
new Unchecked_Conversion (System.Address, Cstring_Ptr);
-- Disable warnings on possible aliasing problem because we only use
-- use this function to convert tags found in the External_Tag of
-- locally defined tagged types.
pragma Warnings (off);
function To_Tag is
new Unchecked_Conversion (Integer_Address, Tag);
pragma Warnings (on);
------------------------------------------------
-- Unchecked Conversions for other components --
------------------------------------------------
type Acc_Size
is access function (A : System.Address) return Long_Long_Integer;
function To_Acc_Size is new Unchecked_Conversion (System.Address, Acc_Size);
-- The profile of the implicitly defined _size primitive
-------------------------------
-- Inline_Always Subprograms --
-------------------------------
-- Inline_always subprograms must be placed before their first call to
-- avoid defeating the frontend inlining mechanism and thus ensure the
-- generation of their correct debug info.
-------------------
-- CW_Membership --
-------------------
-- Canonical implementation of Classwide Membership corresponding to:
-- Obj in Typ'Class
-- Each dispatch table contains a reference to a table of ancestors (stored
-- in the first part of the Tags_Table) and a count of the level of
-- inheritance "Idepth".
-- Obj is in Typ'Class if Typ'Tag is in the table of ancestors that are
-- contained in the dispatch table referenced by Obj'Tag . Knowing the
-- level of inheritance of both types, this can be computed in constant
-- time by the formula:
-- TSD (Obj'tag).Tags_Table (TSD (Obj'tag).Idepth - TSD (Typ'tag).Idepth)
-- = Typ'tag
function CW_Membership (Obj_Tag : Tag; Typ_Tag : Tag) return Boolean is
Obj_TSD_Ptr : constant Addr_Ptr :=
To_Addr_Ptr (To_Address (Obj_Tag) - DT_Typeinfo_Ptr_Size);
Typ_TSD_Ptr : constant Addr_Ptr :=
To_Addr_Ptr (To_Address (Typ_Tag) - DT_Typeinfo_Ptr_Size);
Obj_TSD : constant Type_Specific_Data_Ptr :=
To_Type_Specific_Data_Ptr (Obj_TSD_Ptr.all);
Typ_TSD : constant Type_Specific_Data_Ptr :=
To_Type_Specific_Data_Ptr (Typ_TSD_Ptr.all);
Pos : constant Integer := Obj_TSD.Idepth - Typ_TSD.Idepth;
begin
return Pos >= 0 and then Obj_TSD.Tags_Table (Pos) = Typ_Tag;
end CW_Membership;
----------------------
-- Get_External_Tag --
----------------------
function Get_External_Tag (T : Tag) return System.Address is
TSD_Ptr : constant Addr_Ptr :=
To_Addr_Ptr (To_Address (T) - DT_Typeinfo_Ptr_Size);
TSD : constant Type_Specific_Data_Ptr :=
To_Type_Specific_Data_Ptr (TSD_Ptr.all);
begin
return To_Address (TSD.External_Tag);
end Get_External_Tag;
-------------------
-- Is_Primary_DT --
-------------------
function Is_Primary_DT (T : Tag) return Boolean is
begin
return DT (T).Signature = Primary_DT;
end Is_Primary_DT;
---------
-- OSD --
---------
function OSD (T : Tag) return Object_Specific_Data_Ptr is
OSD_Ptr : constant Addr_Ptr :=
To_Addr_Ptr (To_Address (T) - DT_Typeinfo_Ptr_Size);
begin
return To_Object_Specific_Data_Ptr (OSD_Ptr.all);
end OSD;
---------
-- SSD --
---------
function SSD (T : Tag) return Select_Specific_Data_Ptr is
TSD_Ptr : constant Addr_Ptr :=
To_Addr_Ptr (To_Address (T) - DT_Typeinfo_Ptr_Size);
TSD : constant Type_Specific_Data_Ptr :=
To_Type_Specific_Data_Ptr (TSD_Ptr.all);
begin
return TSD.SSD;
end SSD;
-------------------------
-- External_Tag_HTable --
-------------------------
type HTable_Headers is range 1 .. 64;
-- The following internal package defines the routines used for the
-- instantiation of a new System.HTable.Static_HTable (see below). See
-- spec in g-htable.ads for details of usage.
package HTable_Subprograms is
procedure Set_HT_Link (T : Tag; Next : Tag);
function Get_HT_Link (T : Tag) return Tag;
function Hash (F : System.Address) return HTable_Headers;
function Equal (A, B : System.Address) return Boolean;
end HTable_Subprograms;
package External_Tag_HTable is new System.HTable.Static_HTable (
Header_Num => HTable_Headers,
Element => Dispatch_Table,
Elmt_Ptr => Tag,
Null_Ptr => null,
Set_Next => HTable_Subprograms.Set_HT_Link,
Next => HTable_Subprograms.Get_HT_Link,
Key => System.Address,
Get_Key => Get_External_Tag,
Hash => HTable_Subprograms.Hash,
Equal => HTable_Subprograms.Equal);
------------------------
-- HTable_Subprograms --
------------------------
-- Bodies of routines for hash table instantiation
package body HTable_Subprograms is
-----------
-- Equal --
-----------
function Equal (A, B : System.Address) return Boolean is
Str1 : constant Cstring_Ptr := To_Cstring_Ptr (A);
Str2 : constant Cstring_Ptr := To_Cstring_Ptr (B);
J : Integer := 1;
begin
loop
if Str1 (J) /= Str2 (J) then
return False;
elsif Str1 (J) = ASCII.NUL then
return True;
else
J := J + 1;
end if;
end loop;
end Equal;
-----------------
-- Get_HT_Link --
-----------------
function Get_HT_Link (T : Tag) return Tag is
TSD_Ptr : constant Addr_Ptr :=
To_Addr_Ptr (To_Address (T) - DT_Typeinfo_Ptr_Size);
TSD : constant Type_Specific_Data_Ptr :=
To_Type_Specific_Data_Ptr (TSD_Ptr.all);
begin
return TSD.HT_Link;
end Get_HT_Link;
----------
-- Hash --
----------
function Hash (F : System.Address) return HTable_Headers is
function H is new System.HTable.Hash (HTable_Headers);
Str : constant Cstring_Ptr := To_Cstring_Ptr (F);
Res : constant HTable_Headers := H (Str (1 .. Length (Str)));
begin
return Res;
end Hash;
-----------------
-- Set_HT_Link --
-----------------
procedure Set_HT_Link (T : Tag; Next : Tag) is
TSD_Ptr : constant Addr_Ptr :=
To_Addr_Ptr (To_Address (T) - DT_Typeinfo_Ptr_Size);
TSD : constant Type_Specific_Data_Ptr :=
To_Type_Specific_Data_Ptr (TSD_Ptr.all);
begin
TSD.HT_Link := Next;
end Set_HT_Link;
end HTable_Subprograms;
------------------
-- Base_Address --
------------------
function Base_Address (This : System.Address) return System.Address is
begin
return This - Offset_To_Top (This);
end Base_Address;
--------------
-- Displace --
--------------
function Displace
(This : System.Address;
T : Tag) return System.Address
is
Iface_Table : Interface_Data_Ptr;
Obj_Base : System.Address;
Obj_DT : Dispatch_Table_Ptr;
Obj_DT_Tag : Tag;
begin
if System."=" (This, System.Null_Address) then
return System.Null_Address;
end if;
Obj_Base := Base_Address (This);
Obj_DT_Tag := To_Tag_Ptr (Obj_Base).all;
Obj_DT := DT (To_Tag_Ptr (Obj_Base).all);
Iface_Table := To_Type_Specific_Data_Ptr (Obj_DT.TSD).Interfaces_Table;
if Iface_Table /= null then
for Id in 1 .. Iface_Table.Nb_Ifaces loop
if Iface_Table.Ifaces_Table (Id).Iface_Tag = T then
-- Case of Static value of Offset_To_Top
if Iface_Table.Ifaces_Table (Id).Static_Offset_To_Top then
Obj_Base := Obj_Base +
Iface_Table.Ifaces_Table (Id).Offset_To_Top_Value;
-- Otherwise we call the function generated by the expander
-- to provide us with this value
else
Obj_Base := Obj_Base +
Iface_Table.Ifaces_Table (Id).Offset_To_Top_Func.all
(Obj_Base);
end if;
return Obj_Base;
end if;
end loop;
end if;
-- Check if T is an immediate ancestor. This is required to handle
-- conversion of class-wide interfaces to tagged types.
if CW_Membership (Obj_DT_Tag, T) then
return Obj_Base;
end if;
-- If the object does not implement the interface we must raise CE
raise Constraint_Error;
end Displace;
--------
-- DT --
--------
function DT (T : Tag) return Dispatch_Table_Ptr is
Offset : constant SSE.Storage_Offset :=
To_Dispatch_Table_Ptr (T).Prims_Ptr'Position;
begin
return To_Dispatch_Table_Ptr (To_Address (T) - Offset);
end DT;
-------------------
-- IW_Membership --
-------------------
-- Canonical implementation of Classwide Membership corresponding to:
-- Obj in Iface'Class
-- Each dispatch table contains a table with the tags of all the
-- implemented interfaces.
-- Obj is in Iface'Class if Iface'Tag is found in the table of interfaces
-- that are contained in the dispatch table referenced by Obj'Tag.
function IW_Membership (This : System.Address; T : Tag) return Boolean is
Iface_Table : Interface_Data_Ptr;
Obj_Base : System.Address;
Obj_DT : Dispatch_Table_Ptr;
Obj_TSD : Type_Specific_Data_Ptr;
begin
Obj_Base := Base_Address (This);
Obj_DT := DT (To_Tag_Ptr (Obj_Base).all);
Obj_TSD := To_Type_Specific_Data_Ptr (Obj_DT.TSD);
Iface_Table := Obj_TSD.Interfaces_Table;
if Iface_Table /= null then
for Id in 1 .. Iface_Table.Nb_Ifaces loop
if Iface_Table.Ifaces_Table (Id).Iface_Tag = T then
return True;
end if;
end loop;
end if;
-- Look for the tag in the ancestor tags table. This is required for:
-- Iface_CW in Typ'Class
for Id in 0 .. Obj_TSD.Idepth loop
if Obj_TSD.Tags_Table (Id) = T then
return True;
end if;
end loop;
return False;
end IW_Membership;
--------------------
-- Descendant_Tag --
--------------------
function Descendant_Tag (External : String; Ancestor : Tag) return Tag is
Int_Tag : constant Tag := Internal_Tag (External);
begin
if not Is_Descendant_At_Same_Level (Int_Tag, Ancestor) then
raise Tag_Error;
end if;
return Int_Tag;
end Descendant_Tag;
-------------------
-- Expanded_Name --
-------------------
function Expanded_Name (T : Tag) return String is
Result : Cstring_Ptr;
TSD_Ptr : Addr_Ptr;
TSD : Type_Specific_Data_Ptr;
begin
if T = No_Tag then
raise Tag_Error;
end if;
TSD_Ptr := To_Addr_Ptr (To_Address (T) - DT_Typeinfo_Ptr_Size);
TSD := To_Type_Specific_Data_Ptr (TSD_Ptr.all);
Result := TSD.Expanded_Name;
return Result (1 .. Length (Result));
end Expanded_Name;
------------------
-- External_Tag --
------------------
function External_Tag (T : Tag) return String is
Result : Cstring_Ptr;
TSD_Ptr : Addr_Ptr;
TSD : Type_Specific_Data_Ptr;
begin
if T = No_Tag then
raise Tag_Error;
end if;
TSD_Ptr := To_Addr_Ptr (To_Address (T) - DT_Typeinfo_Ptr_Size);
TSD := To_Type_Specific_Data_Ptr (TSD_Ptr.all);
Result := TSD.External_Tag;
return Result (1 .. Length (Result));
end External_Tag;
---------------------
-- Get_Entry_Index --
---------------------
function Get_Entry_Index (T : Tag; Position : Positive) return Positive is
begin
return SSD (T).SSD_Table (Position).Index;
end Get_Entry_Index;
----------------------
-- Get_Prim_Op_Kind --
----------------------
function Get_Prim_Op_Kind
(T : Tag;
Position : Positive) return Prim_Op_Kind
is
begin
return SSD (T).SSD_Table (Position).Kind;
end Get_Prim_Op_Kind;
----------------------
-- Get_Offset_Index --
----------------------
function Get_Offset_Index
(T : Tag;
Position : Positive) return Positive
is
begin
if Is_Primary_DT (T) then
return Position;
else
return OSD (T).OSD_Table (Position);
end if;
end Get_Offset_Index;
-------------------
-- Get_RC_Offset --
-------------------
function Get_RC_Offset (T : Tag) return SSE.Storage_Offset is
TSD_Ptr : constant Addr_Ptr :=
To_Addr_Ptr (To_Address (T) - DT_Typeinfo_Ptr_Size);
TSD : constant Type_Specific_Data_Ptr :=
To_Type_Specific_Data_Ptr (TSD_Ptr.all);
begin
return TSD.RC_Offset;
end Get_RC_Offset;
---------------------
-- Get_Tagged_Kind --
---------------------
function Get_Tagged_Kind (T : Tag) return Tagged_Kind is
begin
return DT (T).Tag_Kind;
end Get_Tagged_Kind;
-----------------------------
-- Interface_Ancestor_Tags --
-----------------------------
function Interface_Ancestor_Tags (T : Tag) return Tag_Array is
TSD_Ptr : constant Addr_Ptr :=
To_Addr_Ptr (To_Address (T) - DT_Typeinfo_Ptr_Size);
TSD : constant Type_Specific_Data_Ptr :=
To_Type_Specific_Data_Ptr (TSD_Ptr.all);
Iface_Table : constant Interface_Data_Ptr := TSD.Interfaces_Table;
begin
if Iface_Table = null then
declare
Table : Tag_Array (1 .. 0);
begin
return Table;
end;
else
declare
Table : Tag_Array (1 .. Iface_Table.Nb_Ifaces);
begin
for J in 1 .. Iface_Table.Nb_Ifaces loop
Table (J) := Iface_Table.Ifaces_Table (J).Iface_Tag;
end loop;
return Table;
end;
end if;
end Interface_Ancestor_Tags;
------------------
-- Internal_Tag --
------------------
-- Internal tags have the following format:
-- "Internal tag at 16#ADDRESS#: <full-name-of-tagged-type>"
Internal_Tag_Header : constant String := "Internal tag at ";
Header_Separator : constant Character := '#';
function Internal_Tag (External : String) return Tag is
Ext_Copy : aliased String (External'First .. External'Last + 1);
Res : Tag := null;
begin
-- Handle locally defined tagged types
if External'Length > Internal_Tag_Header'Length
and then
External (External'First ..
External'First + Internal_Tag_Header'Length - 1)
= Internal_Tag_Header
then
declare
Addr_First : constant Natural :=
External'First + Internal_Tag_Header'Length;
Addr_Last : Natural;
Addr : Integer_Address;
begin
-- Search the second separator (#) to identify the address
Addr_Last := Addr_First;
for J in 1 .. 2 loop
while Addr_Last <= External'Last
and then External (Addr_Last) /= Header_Separator
loop
Addr_Last := Addr_Last + 1;
end loop;
-- Skip the first separator
if J = 1 then
Addr_Last := Addr_Last + 1;
end if;
end loop;
if Addr_Last <= External'Last then
Addr :=
Integer_Address'Value (External (Addr_First .. Addr_Last));
return To_Tag (Addr);
end if;
end;
-- Handle library-level tagged types
else
-- Make a copy of the string representing the external tag with
-- a null at the end.
Ext_Copy (External'Range) := External;
Ext_Copy (Ext_Copy'Last) := ASCII.NUL;
Res := External_Tag_HTable.Get (Ext_Copy'Address);
end if;
if Res = null then
declare
Msg1 : constant String := "unknown tagged type: ";
Msg2 : String (1 .. Msg1'Length + External'Length);
begin
Msg2 (1 .. Msg1'Length) := Msg1;
Msg2 (Msg1'Length + 1 .. Msg1'Length + External'Length) :=
External;
Ada.Exceptions.Raise_Exception (Tag_Error'Identity, Msg2);
end;
end if;
return Res;
end Internal_Tag;
---------------------------------
-- Is_Descendant_At_Same_Level --
---------------------------------
function Is_Descendant_At_Same_Level
(Descendant : Tag;
Ancestor : Tag) return Boolean
is
D_TSD_Ptr : constant Addr_Ptr :=
To_Addr_Ptr (To_Address (Descendant)
- DT_Typeinfo_Ptr_Size);
A_TSD_Ptr : constant Addr_Ptr :=
To_Addr_Ptr (To_Address (Ancestor) - DT_Typeinfo_Ptr_Size);
D_TSD : constant Type_Specific_Data_Ptr :=
To_Type_Specific_Data_Ptr (D_TSD_Ptr.all);
A_TSD : constant Type_Specific_Data_Ptr :=
To_Type_Specific_Data_Ptr (A_TSD_Ptr.all);
begin
return CW_Membership (Descendant, Ancestor)
and then D_TSD.Access_Level = A_TSD.Access_Level;
end Is_Descendant_At_Same_Level;
------------
-- Length --
------------
function Length (Str : Cstring_Ptr) return Natural is
Len : Integer;
begin
Len := 1;
while Str (Len) /= ASCII.Nul loop
Len := Len + 1;
end loop;
return Len - 1;
end Length;
-------------------
-- Offset_To_Top --
-------------------
function Offset_To_Top
(This : System.Address) return SSE.Storage_Offset
is
Tag_Size : constant SSE.Storage_Count :=
SSE.Storage_Count (1 * (Standard'Address_Size / System.Storage_Unit));
type Storage_Offset_Ptr is access SSE.Storage_Offset;
function To_Storage_Offset_Ptr is
new Unchecked_Conversion (System.Address, Storage_Offset_Ptr);
Curr_DT : Dispatch_Table_Ptr;
begin
Curr_DT := DT (To_Tag_Ptr (This).all);
if Curr_DT.Offset_To_Top = SSE.Storage_Offset'Last then
return To_Storage_Offset_Ptr (This + Tag_Size).all;
else
return Curr_DT.Offset_To_Top;
end if;
end Offset_To_Top;
-----------------
-- Parent_Size --
-----------------
function Parent_Size
(Obj : System.Address;
T : Tag) return SSE.Storage_Count
is
Parent_Slot : constant Positive := 1;
-- The tag of the parent is always in the first slot of the table of
-- ancestor tags.
Size_Slot : constant Positive := 1;
-- The pointer to the _size primitive is always in the first slot of
-- the dispatch table.
TSD_Ptr : constant Addr_Ptr :=
To_Addr_Ptr (To_Address (T) - DT_Typeinfo_Ptr_Size);
TSD : constant Type_Specific_Data_Ptr :=
To_Type_Specific_Data_Ptr (TSD_Ptr.all);
-- Pointer to the TSD
Parent_Tag : constant Tag := TSD.Tags_Table (Parent_Slot);
Parent_Predef_Prims_Ptr : constant Addr_Ptr :=
To_Addr_Ptr (To_Address (Parent_Tag)
- DT_Predef_Prims_Offset);
Parent_Predef_Prims : constant Predef_Prims_Table_Ptr :=
To_Predef_Prims_Table_Ptr
(Parent_Predef_Prims_Ptr.all);
-- The tag of the parent type through the dispatch table and its
-- Predef_Prims field.
F : constant Acc_Size :=
To_Acc_Size (Parent_Predef_Prims (Size_Slot));
-- Access to the _size primitive of the parent
begin
-- Here we compute the size of the _parent field of the object
return SSE.Storage_Count (F.all (Obj));
end Parent_Size;
----------------
-- Parent_Tag --
----------------
function Parent_Tag (T : Tag) return Tag is
TSD_Ptr : Addr_Ptr;
TSD : Type_Specific_Data_Ptr;
begin
if T = No_Tag then
raise Tag_Error;
end if;
TSD_Ptr := To_Addr_Ptr (To_Address (T) - DT_Typeinfo_Ptr_Size);
TSD := To_Type_Specific_Data_Ptr (TSD_Ptr.all);
-- The Parent_Tag of a root-level tagged type is defined to be No_Tag.
-- The first entry in the Ancestors_Tags array will be null for such
-- a type, but it's better to be explicit about returning No_Tag in
-- this case.
if TSD.Idepth = 0 then
return No_Tag;
else
return TSD.Tags_Table (1);
end if;
end Parent_Tag;
------------------
-- Register_Tag --
------------------
procedure Register_Tag (T : Tag) is
begin
External_Tag_HTable.Set (T);
end Register_Tag;
---------------------
-- Set_Entry_Index --
---------------------
procedure Set_Entry_Index
(T : Tag;
Position : Positive;
Value : Positive)
is
begin
SSD (T).SSD_Table (Position).Index := Value;
end Set_Entry_Index;
-----------------------
-- Set_Offset_To_Top --
-----------------------
procedure Set_Offset_To_Top
(This : System.Address;
Interface_T : Tag;
Is_Static : Boolean;
Offset_Value : SSE.Storage_Offset;
Offset_Func : Offset_To_Top_Function_Ptr)
is
Prim_DT : Dispatch_Table_Ptr;
Sec_Base : System.Address;
Sec_DT : Dispatch_Table_Ptr;
Iface_Table : Interface_Data_Ptr;
begin
-- Save the offset to top field in the secondary dispatch table
if Offset_Value /= 0 then
Sec_Base := This + Offset_Value;
Sec_DT := DT (To_Tag_Ptr (Sec_Base).all);
if Is_Static then
Sec_DT.Offset_To_Top := Offset_Value;
else
Sec_DT.Offset_To_Top := SSE.Storage_Offset'Last;
end if;
end if;
-- "This" points to the primary DT and we must save Offset_Value in
-- the Offset_To_Top field of the corresponding secondary dispatch
-- table.
Prim_DT := DT (To_Tag_Ptr (This).all);
Iface_Table := To_Type_Specific_Data_Ptr (Prim_DT.TSD).Interfaces_Table;
-- Save Offset_Value in the table of interfaces of the primary DT.
-- This data will be used by the subprogram "Displace" to give support
-- to backward abstract interface type conversions.
-- Register the offset in the table of interfaces
if Iface_Table /= null then
for Id in 1 .. Iface_Table.Nb_Ifaces loop
if Iface_Table.Ifaces_Table (Id).Iface_Tag = Interface_T then
Iface_Table.Ifaces_Table (Id).Static_Offset_To_Top :=
Is_Static;
if Is_Static then
Iface_Table.Ifaces_Table (Id).Offset_To_Top_Value
:= Offset_Value;
else
Iface_Table.Ifaces_Table (Id).Offset_To_Top_Func
:= Offset_Func;
end if;
return;
end if;
end loop;
end if;
-- If we arrive here there is some error in the run-time data structure
raise Program_Error;
end Set_Offset_To_Top;
----------------------
-- Set_Prim_Op_Kind --
----------------------
procedure Set_Prim_Op_Kind
(T : Tag;
Position : Positive;
Value : Prim_Op_Kind)
is
begin
SSD (T).SSD_Table (Position).Kind := Value;
end Set_Prim_Op_Kind;
------------------------
-- Wide_Expanded_Name --
------------------------
WC_Encoding : Character;
pragma Import (C, WC_Encoding, "__gl_wc_encoding");
-- Encoding method for source, as exported by binder
function Wide_Expanded_Name (T : Tag) return Wide_String is
begin
return String_To_Wide_String
(Expanded_Name (T), Get_WC_Encoding_Method (WC_Encoding));
end Wide_Expanded_Name;
-----------------------------
-- Wide_Wide_Expanded_Name --
-----------------------------
function Wide_Wide_Expanded_Name (T : Tag) return Wide_Wide_String is
begin
return String_To_Wide_Wide_String
(Expanded_Name (T), Get_WC_Encoding_Method (WC_Encoding));
end Wide_Wide_Expanded_Name;
end Ada.Tags;
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