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|
------------------------------------------------------------------------------
-- --
-- GNAT COMPILER COMPONENTS --
-- --
-- E X P _ A T A G --
-- --
-- S p e c --
-- --
-- Copyright (C) 2006-2008, 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. --
-- --
------------------------------------------------------------------------------
with Einfo; use Einfo;
with Elists; use Elists;
with Exp_Util; use Exp_Util;
with Namet; use Namet;
with Nlists; use Nlists;
with Nmake; use Nmake;
with Rtsfind; use Rtsfind;
with Sinfo; use Sinfo;
with Sem_Util; use Sem_Util;
with Stand; use Stand;
with Snames; use Snames;
with Tbuild; use Tbuild;
package body Exp_Atag is
-----------------------
-- Local Subprograms --
-----------------------
function Build_DT
(Loc : Source_Ptr;
Tag_Node : Node_Id) return Node_Id;
-- Build code that displaces the Tag to reference the base of the wrapper
-- record
--
-- Generates:
-- To_Dispatch_Table_Ptr
-- (To_Address (Tag_Node) - Tag_Node.Prims_Ptr'Position);
function Build_TSD (Loc : Source_Ptr; Tag_Node : Node_Id) return Node_Id;
-- Build code that retrieves the address of the record containing the Type
-- Specific Data generated by GNAT.
--
-- Generate: To_Type_Specific_Data_Ptr
-- (To_Addr_Ptr (To_Address (Tag) - Typeinfo_Offset).all);
------------------------------------------------
-- Build_Common_Dispatching_Select_Statements --
------------------------------------------------
procedure Build_Common_Dispatching_Select_Statements
(Loc : Source_Ptr;
DT_Ptr : Entity_Id;
Stmts : List_Id)
is
begin
-- Generate:
-- C := get_prim_op_kind (tag! (<type>VP), S);
-- where C is the out parameter capturing the call kind and S is the
-- dispatch table slot number.
Append_To (Stmts,
Make_Assignment_Statement (Loc,
Name =>
Make_Identifier (Loc, Name_uC),
Expression =>
Make_Function_Call (Loc,
Name => New_Occurrence_Of (RTE (RE_Get_Prim_Op_Kind), Loc),
Parameter_Associations => New_List (
Unchecked_Convert_To (RTE (RE_Tag),
New_Reference_To (DT_Ptr, Loc)),
Make_Identifier (Loc, Name_uS)))));
-- Generate:
-- if C = POK_Procedure
-- or else C = POK_Protected_Procedure
-- or else C = POK_Task_Procedure;
-- then
-- F := True;
-- return;
-- where F is the out parameter capturing the status of a potential
-- entry call.
Append_To (Stmts,
Make_If_Statement (Loc,
Condition =>
Make_Or_Else (Loc,
Left_Opnd =>
Make_Op_Eq (Loc,
Left_Opnd =>
Make_Identifier (Loc, Name_uC),
Right_Opnd =>
New_Reference_To (RTE (RE_POK_Procedure), Loc)),
Right_Opnd =>
Make_Or_Else (Loc,
Left_Opnd =>
Make_Op_Eq (Loc,
Left_Opnd =>
Make_Identifier (Loc, Name_uC),
Right_Opnd =>
New_Reference_To (RTE (
RE_POK_Protected_Procedure), Loc)),
Right_Opnd =>
Make_Op_Eq (Loc,
Left_Opnd =>
Make_Identifier (Loc, Name_uC),
Right_Opnd =>
New_Reference_To (RTE (
RE_POK_Task_Procedure), Loc)))),
Then_Statements =>
New_List (
Make_Assignment_Statement (Loc,
Name => Make_Identifier (Loc, Name_uF),
Expression => New_Reference_To (Standard_True, Loc)),
Make_Simple_Return_Statement (Loc))));
end Build_Common_Dispatching_Select_Statements;
-------------------------
-- Build_CW_Membership --
-------------------------
function Build_CW_Membership
(Loc : Source_Ptr;
Obj_Tag_Node : Node_Id;
Typ_Tag_Node : Node_Id) return Node_Id
is
function Build_Pos return Node_Id;
-- Generate TSD (Obj_Tag).Idepth - TSD (Typ_Tag).Idepth;
function Build_Pos return Node_Id is
begin
return
Make_Op_Subtract (Loc,
Left_Opnd =>
Make_Selected_Component (Loc,
Prefix => Build_TSD (Loc, Duplicate_Subexpr (Obj_Tag_Node)),
Selector_Name =>
New_Reference_To (RTE_Record_Component (RE_Idepth), Loc)),
Right_Opnd =>
Make_Selected_Component (Loc,
Prefix => Build_TSD (Loc, Duplicate_Subexpr (Typ_Tag_Node)),
Selector_Name =>
New_Reference_To (RTE_Record_Component (RE_Idepth), Loc)));
end Build_Pos;
-- Start of processing for Build_CW_Membership
begin
return
Make_And_Then (Loc,
Left_Opnd =>
Make_Op_Ge (Loc,
Left_Opnd => Build_Pos,
Right_Opnd => Make_Integer_Literal (Loc, Uint_0)),
Right_Opnd =>
Make_Op_Eq (Loc,
Left_Opnd =>
Make_Indexed_Component (Loc,
Prefix =>
Make_Selected_Component (Loc,
Prefix => Build_TSD (Loc, Obj_Tag_Node),
Selector_Name =>
New_Reference_To
(RTE_Record_Component (RE_Tags_Table), Loc)),
Expressions =>
New_List (Build_Pos)),
Right_Opnd => Typ_Tag_Node));
end Build_CW_Membership;
--------------
-- Build_DT --
--------------
function Build_DT
(Loc : Source_Ptr;
Tag_Node : Node_Id) return Node_Id is
begin
return
Make_Function_Call (Loc,
Name => New_Reference_To (RTE (RE_DT), Loc),
Parameter_Associations => New_List (
Unchecked_Convert_To (RTE (RE_Tag), Tag_Node)));
end Build_DT;
----------------------------
-- Build_Get_Access_Level --
----------------------------
function Build_Get_Access_Level
(Loc : Source_Ptr;
Tag_Node : Node_Id) return Node_Id
is
begin
return
Make_Selected_Component (Loc,
Prefix => Build_TSD (Loc, Tag_Node),
Selector_Name =>
New_Reference_To
(RTE_Record_Component (RE_Access_Level), Loc));
end Build_Get_Access_Level;
------------------------------------------
-- Build_Get_Predefined_Prim_Op_Address --
------------------------------------------
function Build_Get_Predefined_Prim_Op_Address
(Loc : Source_Ptr;
Tag_Node : Node_Id;
Position : Uint) return Node_Id
is
begin
-- Build code that retrieves the address of the dispatch table
-- containing the predefined Ada primitives:
--
-- Generate:
-- To_Predef_Prims_Table_Ptr
-- (To_Addr_Ptr (To_Address (Tag) - Predef_Prims_Offset).all);
return
Make_Indexed_Component (Loc,
Prefix =>
Unchecked_Convert_To (RTE (RE_Predef_Prims_Table_Ptr),
Make_Explicit_Dereference (Loc,
Unchecked_Convert_To (RTE (RE_Addr_Ptr),
Make_Function_Call (Loc,
Name =>
Make_Expanded_Name (Loc,
Chars => Name_Op_Subtract,
Prefix =>
New_Reference_To
(RTU_Entity (System_Storage_Elements), Loc),
Selector_Name =>
Make_Identifier (Loc,
Chars => Name_Op_Subtract)),
Parameter_Associations => New_List (
Unchecked_Convert_To (RTE (RE_Address), Tag_Node),
New_Reference_To (RTE (RE_DT_Predef_Prims_Offset),
Loc)))))),
Expressions =>
New_List (Make_Integer_Literal (Loc, Position)));
end Build_Get_Predefined_Prim_Op_Address;
-------------------------
-- Build_Inherit_Prims --
-------------------------
function Build_Inherit_Prims
(Loc : Source_Ptr;
Typ : Entity_Id;
Old_Tag_Node : Node_Id;
New_Tag_Node : Node_Id;
Num_Prims : Nat) return Node_Id
is
begin
if RTE_Available (RE_DT) then
return
Make_Assignment_Statement (Loc,
Name =>
Make_Slice (Loc,
Prefix =>
Make_Selected_Component (Loc,
Prefix =>
Build_DT (Loc, New_Tag_Node),
Selector_Name =>
New_Reference_To
(RTE_Record_Component (RE_Prims_Ptr), Loc)),
Discrete_Range =>
Make_Range (Loc,
Low_Bound => Make_Integer_Literal (Loc, 1),
High_Bound => Make_Integer_Literal (Loc, Num_Prims))),
Expression =>
Make_Slice (Loc,
Prefix =>
Make_Selected_Component (Loc,
Prefix =>
Build_DT (Loc, Old_Tag_Node),
Selector_Name =>
New_Reference_To
(RTE_Record_Component (RE_Prims_Ptr), Loc)),
Discrete_Range =>
Make_Range (Loc,
Low_Bound => Make_Integer_Literal (Loc, 1),
High_Bound => Make_Integer_Literal (Loc, Num_Prims))));
else
return
Make_Assignment_Statement (Loc,
Name =>
Make_Slice (Loc,
Prefix =>
Unchecked_Convert_To
(Node (Last_Elmt (Access_Disp_Table (Typ))),
New_Tag_Node),
Discrete_Range =>
Make_Range (Loc,
Low_Bound => Make_Integer_Literal (Loc, 1),
High_Bound => Make_Integer_Literal (Loc, Num_Prims))),
Expression =>
Make_Slice (Loc,
Prefix =>
Unchecked_Convert_To
(Node (Last_Elmt (Access_Disp_Table (Typ))),
Old_Tag_Node),
Discrete_Range =>
Make_Range (Loc,
Low_Bound => Make_Integer_Literal (Loc, 1),
High_Bound => Make_Integer_Literal (Loc, Num_Prims))));
end if;
end Build_Inherit_Prims;
-------------------------------
-- Build_Get_Prim_Op_Address --
-------------------------------
function Build_Get_Prim_Op_Address
(Loc : Source_Ptr;
Typ : Entity_Id;
Tag_Node : Node_Id;
Position : Uint) return Node_Id
is
begin
pragma Assert
(Position <= DT_Entry_Count (First_Tag_Component (Typ)));
-- At the end of the Access_Disp_Table list we have the type
-- declaration required to convert the tag into a pointer to
-- the prims_ptr table (see Freeze_Record_Type).
return
Make_Indexed_Component (Loc,
Prefix =>
Unchecked_Convert_To
(Node (Last_Elmt (Access_Disp_Table (Typ))), Tag_Node),
Expressions => New_List (Make_Integer_Literal (Loc, Position)));
end Build_Get_Prim_Op_Address;
-----------------------------
-- Build_Get_Transportable --
-----------------------------
function Build_Get_Transportable
(Loc : Source_Ptr;
Tag_Node : Node_Id) return Node_Id
is
begin
return
Make_Selected_Component (Loc,
Prefix => Build_TSD (Loc, Tag_Node),
Selector_Name =>
New_Reference_To
(RTE_Record_Component (RE_Transportable), Loc));
end Build_Get_Transportable;
------------------------------------
-- Build_Inherit_Predefined_Prims --
------------------------------------
function Build_Inherit_Predefined_Prims
(Loc : Source_Ptr;
Old_Tag_Node : Node_Id;
New_Tag_Node : Node_Id) return Node_Id
is
begin
return
Make_Assignment_Statement (Loc,
Name =>
Make_Slice (Loc,
Prefix =>
Make_Explicit_Dereference (Loc,
Unchecked_Convert_To (RTE (RE_Predef_Prims_Table_Ptr),
Make_Explicit_Dereference (Loc,
Unchecked_Convert_To (RTE (RE_Addr_Ptr),
New_Tag_Node)))),
Discrete_Range => Make_Range (Loc,
Make_Integer_Literal (Loc, Uint_1),
New_Reference_To (RTE (RE_Max_Predef_Prims), Loc))),
Expression =>
Make_Slice (Loc,
Prefix =>
Make_Explicit_Dereference (Loc,
Unchecked_Convert_To (RTE (RE_Predef_Prims_Table_Ptr),
Make_Explicit_Dereference (Loc,
Unchecked_Convert_To (RTE (RE_Addr_Ptr),
Old_Tag_Node)))),
Discrete_Range =>
Make_Range (Loc,
Make_Integer_Literal (Loc, 1),
New_Reference_To (RTE (RE_Max_Predef_Prims), Loc))));
end Build_Inherit_Predefined_Prims;
-------------------------
-- Build_Offset_To_Top --
-------------------------
function Build_Offset_To_Top
(Loc : Source_Ptr;
This_Node : Node_Id) return Node_Id
is
Tag_Node : Node_Id;
begin
Tag_Node :=
Make_Explicit_Dereference (Loc,
Unchecked_Convert_To (RTE (RE_Tag_Ptr), This_Node));
return
Make_Explicit_Dereference (Loc,
Unchecked_Convert_To (RTE (RE_Offset_To_Top_Ptr),
Make_Function_Call (Loc,
Name =>
Make_Expanded_Name (Loc,
Chars => Name_Op_Subtract,
Prefix => New_Reference_To
(RTU_Entity (System_Storage_Elements), Loc),
Selector_Name => Make_Identifier (Loc,
Chars => Name_Op_Subtract)),
Parameter_Associations => New_List (
Unchecked_Convert_To (RTE (RE_Address), Tag_Node),
New_Reference_To (RTE (RE_DT_Offset_To_Top_Offset),
Loc)))));
end Build_Offset_To_Top;
------------------------------------------
-- Build_Set_Predefined_Prim_Op_Address --
------------------------------------------
function Build_Set_Predefined_Prim_Op_Address
(Loc : Source_Ptr;
Tag_Node : Node_Id;
Position : Uint;
Address_Node : Node_Id) return Node_Id
is
begin
return
Make_Assignment_Statement (Loc,
Name =>
Make_Indexed_Component (Loc,
Prefix =>
Unchecked_Convert_To (RTE (RE_Predef_Prims_Table_Ptr),
Make_Explicit_Dereference (Loc,
Unchecked_Convert_To (RTE (RE_Addr_Ptr), Tag_Node))),
Expressions =>
New_List (Make_Integer_Literal (Loc, Position))),
Expression => Address_Node);
end Build_Set_Predefined_Prim_Op_Address;
-------------------------------
-- Build_Set_Prim_Op_Address --
-------------------------------
function Build_Set_Prim_Op_Address
(Loc : Source_Ptr;
Typ : Entity_Id;
Tag_Node : Node_Id;
Position : Uint;
Address_Node : Node_Id) return Node_Id
is
begin
return
Make_Assignment_Statement (Loc,
Name => Build_Get_Prim_Op_Address
(Loc, Typ, Tag_Node, Position),
Expression => Address_Node);
end Build_Set_Prim_Op_Address;
-----------------------------
-- Build_Set_Size_Function --
-----------------------------
function Build_Set_Size_Function
(Loc : Source_Ptr;
Tag_Node : Node_Id;
Size_Func : Entity_Id) return Node_Id is
begin
pragma Assert (Chars (Size_Func) = Name_uSize
and then RTE_Record_Component_Available (RE_Size_Func));
return
Make_Assignment_Statement (Loc,
Name =>
Make_Selected_Component (Loc,
Prefix => Build_TSD (Loc, Tag_Node),
Selector_Name =>
New_Reference_To
(RTE_Record_Component (RE_Size_Func), Loc)),
Expression =>
Unchecked_Convert_To (RTE (RE_Size_Ptr),
Make_Attribute_Reference (Loc,
Prefix => New_Reference_To (Size_Func, Loc),
Attribute_Name => Name_Unrestricted_Access)));
end Build_Set_Size_Function;
------------------------------------
-- Build_Set_Static_Offset_To_Top --
------------------------------------
function Build_Set_Static_Offset_To_Top
(Loc : Source_Ptr;
Iface_Tag : Node_Id;
Offset_Value : Node_Id) return Node_Id is
begin
return
Make_Assignment_Statement (Loc,
Make_Explicit_Dereference (Loc,
Unchecked_Convert_To (RTE (RE_Offset_To_Top_Ptr),
Make_Function_Call (Loc,
Name =>
Make_Expanded_Name (Loc,
Chars => Name_Op_Subtract,
Prefix => New_Reference_To
(RTU_Entity (System_Storage_Elements), Loc),
Selector_Name => Make_Identifier (Loc,
Chars => Name_Op_Subtract)),
Parameter_Associations => New_List (
Unchecked_Convert_To (RTE (RE_Address), Iface_Tag),
New_Reference_To (RTE (RE_DT_Offset_To_Top_Offset),
Loc))))),
Offset_Value);
end Build_Set_Static_Offset_To_Top;
---------------
-- Build_TSD --
---------------
function Build_TSD (Loc : Source_Ptr; Tag_Node : Node_Id) return Node_Id is
begin
return
Unchecked_Convert_To (RTE (RE_Type_Specific_Data_Ptr),
Make_Explicit_Dereference (Loc,
Prefix => Unchecked_Convert_To (RTE (RE_Addr_Ptr),
Make_Function_Call (Loc,
Name =>
Make_Expanded_Name (Loc,
Chars => Name_Op_Subtract,
Prefix =>
New_Reference_To
(RTU_Entity (System_Storage_Elements), Loc),
Selector_Name =>
Make_Identifier (Loc,
Chars => Name_Op_Subtract)),
Parameter_Associations => New_List (
Unchecked_Convert_To (RTE (RE_Address), Tag_Node),
New_Reference_To
(RTE (RE_DT_Typeinfo_Ptr_Size), Loc))))));
end Build_TSD;
end Exp_Atag;
|
