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-- --
-- --
-- E X P _ P R A G --
-- --
-- B o d y --
-- --
-- Copyright (C) 1992-2003 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, 59 Temple Place - Suite 330, Boston, --
-- MA 02111-1307, USA. --
-- --
-- GNAT was originally developed by the GNAT team at New York University. --
-- Extensive contributions were provided by Ada Core Technologies Inc. --
-- --
with Atree; use Atree;
with Casing; use Casing;
with Einfo; use Einfo;
with Errout; use Errout;
with Exp_Ch11; use Exp_Ch11;
with Exp_Tss; use Exp_Tss;
with Exp_Util; use Exp_Util;
with Expander; use Expander;
with Namet; use Namet;
with Nlists; use Nlists;
with Nmake; use Nmake;
with Opt; use Opt;
with Rtsfind; use Rtsfind;
with Sem; use Sem;
with Sem_Eval; use Sem_Eval;
with Sem_Res; use Sem_Res;
with Sem_Util; use Sem_Util;
with Sinfo; use Sinfo;
with Sinput; use Sinput;
with Snames; use Snames;
with Stringt; use Stringt;
with Stand; use Stand;
with Targparm; use Targparm;
with Tbuild; use Tbuild;
with Uintp; use Uintp;
package body Exp_Prag is
-- Local Subprograms --
function Arg1 (N : Node_Id) return Node_Id;
function Arg2 (N : Node_Id) return Node_Id;
-- Obtain specified Pragma_Argument_Association
procedure Expand_Pragma_Abort_Defer (N : Node_Id);
procedure Expand_Pragma_Assert (N : Node_Id);
procedure Expand_Pragma_Import (N : Node_Id);
procedure Expand_Pragma_Import_Export_Exception (N : Node_Id);
procedure Expand_Pragma_Inspection_Point (N : Node_Id);
procedure Expand_Pragma_Interrupt_Priority (N : Node_Id);
-- Arg1 --
function Arg1 (N : Node_Id) return Node_Id is
return First (Pragma_Argument_Associations (N));
end Arg1;
-- Arg2 --
function Arg2 (N : Node_Id) return Node_Id is
return Next (Arg1 (N));
end Arg2;
-- Expand_N_Pragma --
procedure Expand_N_Pragma (N : Node_Id) is
-- Note: we may have a pragma whose chars field is not a
-- recognized pragma, and we must ignore it at this stage.
if Is_Pragma_Name (Chars (N)) then
case Get_Pragma_Id (Chars (N)) is
-- Pragmas requiring special expander action
when Pragma_Abort_Defer =>
Expand_Pragma_Abort_Defer (N);
when Pragma_Assert =>
Expand_Pragma_Assert (N);
when Pragma_Export_Exception =>
Expand_Pragma_Import_Export_Exception (N);
when Pragma_Import =>
Expand_Pragma_Import (N);
when Pragma_Import_Exception =>
Expand_Pragma_Import_Export_Exception (N);
when Pragma_Inspection_Point =>
Expand_Pragma_Inspection_Point (N);
when Pragma_Interrupt_Priority =>
Expand_Pragma_Interrupt_Priority (N);
-- All other pragmas need no expander action
when others => null;
end case;
end if;
end Expand_N_Pragma;
-- Expand_Pragma_Abort_Defer --
-- An Abort_Defer pragma appears as the first statement in a handled
-- statement sequence (right after the begin). It defers aborts for
-- the entire statement sequence, but not for any declarations or
-- handlers (if any) associated with this statement sequence.
-- The transformation is to transform
-- pragma Abort_Defer;
-- statements;
-- into
-- begin
-- Abort_Defer.all;
-- statements
-- exception
-- when all others =>
-- Abort_Undefer.all;
-- raise;
-- at end
-- Abort_Undefer_Direct;
-- end;
procedure Expand_Pragma_Abort_Defer (N : Node_Id) is
Loc : constant Source_Ptr := Sloc (N);
Stm : Node_Id;
Stms : List_Id;
HSS : Node_Id;
Blk : constant Entity_Id :=
New_Internal_Entity (E_Block, Current_Scope, Sloc (N), 'B');
Stms := New_List (Build_Runtime_Call (Loc, RE_Abort_Defer));
Stm := Remove_Next (N);
exit when No (Stm);
Append (Stm, Stms);
end loop;
HSS :=
Make_Handled_Sequence_Of_Statements (Loc,
Statements => Stms,
At_End_Proc =>
New_Occurrence_Of (RTE (RE_Abort_Undefer_Direct), Loc));
Rewrite (N,
Make_Block_Statement (Loc,
Handled_Statement_Sequence => HSS));
Set_Scope (Blk, Current_Scope);
Set_Etype (Blk, Standard_Void_Type);
Set_Identifier (N, New_Occurrence_Of (Blk, Sloc (N)));
Expand_At_End_Handler (HSS, Blk);
Analyze (N);
end Expand_Pragma_Abort_Defer;
-- Expand_Pragma_Assert --
procedure Expand_Pragma_Assert (N : Node_Id) is
Loc : constant Source_Ptr := Sloc (N);
Cond : constant Node_Id := Expression (Arg1 (N));
Msg : String_Id;
-- We already know that assertions are enabled, because otherwise
-- the semantic pass dealt with rewriting the assertion (see Sem_Prag)
pragma Assert (Assertions_Enabled);
-- Since assertions are on, we rewrite the pragma with its
-- corresponding if statement, and then analyze the statement
-- The expansion transforms:
-- pragma Assert (condition [,message]);
-- into
-- if not condition then
-- System.Assertions.Raise_Assert_Failure (Str);
-- end if;
-- where Str is the message if one is present, or the default of
-- file:line if no message is given.
-- First, we need to prepare the character literal
if Present (Arg2 (N)) then
Msg := Strval (Expr_Value_S (Expression (Arg2 (N))));
Build_Location_String (Loc);
Msg := String_From_Name_Buffer;
end if;
-- Now generate the if statement. Note that we consider this to be
-- an explicit conditional in the source, not an implicit if, so we
-- do not call Make_Implicit_If_Statement.
Rewrite (N,
Make_If_Statement (Loc,
Condition =>
Make_Op_Not (Loc,
Right_Opnd => Cond),
Then_Statements => New_List (
Make_Procedure_Call_Statement (Loc,
Name =>
New_Reference_To (RTE (RE_Raise_Assert_Failure), Loc),
Parameter_Associations => New_List (
Make_String_Literal (Loc, Msg))))));
Analyze (N);
-- If new condition is always false, give a warning
if Nkind (N) = N_Procedure_Call_Statement
and then Is_RTE (Entity (Name (N)), RE_Raise_Assert_Failure)
-- If original condition was a Standard.False, we assume
-- that this is indeed intented to raise assert error
-- and no warning is required.
if Is_Entity_Name (Original_Node (Cond))
and then Entity (Original_Node (Cond)) = Standard_False
Error_Msg_N ("?assertion will fail at run-time", N);
end if;
end if;
end Expand_Pragma_Assert;
-- Expand_Pragma_Import --
-- When applied to a variable, the default initialization must not be
-- done. As it is already done when the pragma is found, we just get rid
-- of the call the initialization procedure which followed the object
-- declaration.
-- We can't use the freezing mechanism for this purpose, since we
-- have to elaborate the initialization expression when it is first
-- seen (i.e. this elaboration cannot be deferred to the freeze point).
procedure Expand_Pragma_Import (N : Node_Id) is
Def_Id : constant Entity_Id := Entity (Expression (Arg2 (N)));
Typ : Entity_Id;
After_Def : Node_Id;
if Ekind (Def_Id) = E_Variable then
Typ := Etype (Def_Id);
After_Def := Next (Parent (Def_Id));
if Has_Non_Null_Base_Init_Proc (Typ)
and then Nkind (After_Def) = N_Procedure_Call_Statement
and then Is_Entity_Name (Name (After_Def))
and then Entity (Name (After_Def)) = Base_Init_Proc (Typ)
Remove (After_Def);
-- Any default initialization expression should be removed
-- (e.g., null defaults for access objects, zero initialization
-- of packed bit arrays). Imported objects aren't allowed to
-- have explicit initialization, so the expression must have
-- been generated by the compiler.
elsif Present (Expression (Parent (Def_Id))) then
Set_Expression (Parent (Def_Id), Empty);
end if;
end if;
end Expand_Pragma_Import;
-- Expand_Pragma_Import_Export_Exception --
-- For a VMS exception fix up the language field with "VMS"
-- instead of "Ada" (gigi needs this), create a constant that will be the
-- value of the VMS condition code and stuff the Interface_Name field
-- with the unexpanded name of the exception (if not already set).
-- For a Ada exception, just stuff the Interface_Name field
-- with the unexpanded name of the exception (if not already set).
procedure Expand_Pragma_Import_Export_Exception (N : Node_Id) is
-- This pragma is only effective on OpenVMS systems, it was ignored
-- on non-VMS systems, and we need to ignore it here as well.
if not OpenVMS_On_Target then
end if;
Id : constant Entity_Id := Entity (Expression (Arg1 (N)));
Call : constant Node_Id := Register_Exception_Call (Id);
Loc : constant Source_Ptr := Sloc (N);
if Present (Call) then
Excep_Internal : constant Node_Id :=
(Loc, New_Internal_Name ('V'));
Export_Pragma : Node_Id;
Excep_Alias : Node_Id;
Excep_Object : Node_Id;
Excep_Image : String_Id;
Exdata : List_Id;
Lang1 : Node_Id;
Lang2 : Node_Id;
Lang3 : Node_Id;
Code : Node_Id;
if Present (Interface_Name (Id)) then
Excep_Image := Strval (Interface_Name (Id));
Get_Name_String (Chars (Id));
Excep_Image := String_From_Name_Buffer;
end if;
Exdata := Component_Associations (Expression (Parent (Id)));
if Is_VMS_Exception (Id) then
Lang1 := Next (First (Exdata));
Lang2 := Next (Lang1);
Lang3 := Next (Lang2);
Rewrite (Expression (Lang1),
Make_Character_Literal (Loc,
Chars => Name_uV,
Char_Literal_Value => Get_Char_Code ('V')));
Analyze (Expression (Lang1));
Rewrite (Expression (Lang2),
Make_Character_Literal (Loc,
Chars => Name_uM,
Char_Literal_Value => Get_Char_Code ('M')));
Analyze (Expression (Lang2));
Rewrite (Expression (Lang3),
Make_Character_Literal (Loc,
Chars => Name_uS,
Char_Literal_Value => Get_Char_Code ('S')));
Analyze (Expression (Lang3));
if Exception_Code (Id) /= No_Uint then
Code :=
Make_Integer_Literal (Loc,
Intval => Exception_Code (Id));
Excep_Object :=
Make_Object_Declaration (Loc,
Defining_Identifier => Excep_Internal,
Object_Definition =>
New_Reference_To (Standard_Integer, Loc));
Insert_Action (N, Excep_Object);
Analyze (Excep_Object);
(UI_To_Int (Exception_Code (Id)) / 8 * 8);
Excep_Alias :=
(Sloc => Loc,
Expression =>
New_Reference_To (Excep_Internal, Loc)),
(Sloc => Loc,
Expression =>
(Sloc => Loc,
Strval => End_String))));
Insert_Action (N, Excep_Alias);
Analyze (Excep_Alias);
Export_Pragma :=
(Sloc => Loc,
Expression => Make_Identifier (Loc, Name_C)),
(Sloc => Loc,
Expression =>
New_Reference_To (Excep_Internal, Loc)),
(Sloc => Loc,
Expression =>
(Sloc => Loc,
Strval => Excep_Image)),
(Sloc => Loc,
Expression =>
(Sloc => Loc,
Strval => Excep_Image))));
Insert_Action (N, Export_Pragma);
Analyze (Export_Pragma);
Code :=
Unchecked_Convert_To (Standard_Integer,
Make_Function_Call (Loc,
Name =>
New_Reference_To (RTE (RE_Import_Value), Loc),
Parameter_Associations => New_List
(Make_String_Literal (Loc,
Strval => Excep_Image))));
end if;
Rewrite (Call,
Make_Procedure_Call_Statement (Loc,
Name => New_Reference_To
(RTE (RE_Register_VMS_Exception), Loc),
Parameter_Associations => New_List (Code)));
Analyze_And_Resolve (Code, Standard_Integer);
Analyze (Call);
end if;
if not Present (Interface_Name (Id)) then
Set_Interface_Name (Id,
(Sloc => Loc,
Strval => Excep_Image));
end if;
end if;
end Expand_Pragma_Import_Export_Exception;
-- Expand_Pragma_Inspection_Point --
-- If no argument is given, then we supply a default argument list that
-- includes all objects declared at the source level in all subprograms
-- that enclose the inspection point pragma.
procedure Expand_Pragma_Inspection_Point (N : Node_Id) is
Loc : constant Source_Ptr := Sloc (N);
A : List_Id;
Assoc : Node_Id;
S : Entity_Id;
E : Entity_Id;
if No (Pragma_Argument_Associations (N)) then
A := New_List;
S := Current_Scope;
while S /= Standard_Standard loop
E := First_Entity (S);
while Present (E) loop
if Comes_From_Source (E)
and then Is_Object (E)
and then not Is_Entry_Formal (E)
and then Ekind (E) /= E_Component
and then Ekind (E) /= E_Discriminant
and then Ekind (E) /= E_Generic_In_Parameter
and then Ekind (E) /= E_Generic_In_Out_Parameter
Append_To (A,
Make_Pragma_Argument_Association (Loc,
Expression => New_Occurrence_Of (E, Loc)));
end if;
Next_Entity (E);
end loop;
S := Scope (S);
end loop;
Set_Pragma_Argument_Associations (N, A);
end if;
-- Expand the arguments of the pragma. Expanding an entity reference
-- is a noop, except in a protected operation, where a reference may
-- have to be transformed into a reference to the corresponding prival.
-- Are there other pragmas that may require this ???
Assoc := First (Pragma_Argument_Associations (N));
while Present (Assoc) loop
Expand (Expression (Assoc));
Next (Assoc);
end loop;
end Expand_Pragma_Inspection_Point;
-- Expand_Pragma_Interrupt_Priority --
-- Supply default argument if none exists (System.Interrupt_Priority'Last)
procedure Expand_Pragma_Interrupt_Priority (N : Node_Id) is
Loc : constant Source_Ptr := Sloc (N);
if No (Pragma_Argument_Associations (N)) then
Set_Pragma_Argument_Associations (N, New_List (
Make_Pragma_Argument_Association (Loc,
Expression =>
Make_Attribute_Reference (Loc,
Prefix =>
New_Occurrence_Of (RTE (RE_Interrupt_Priority), Loc),
Attribute_Name => Name_Last))));
end if;
end Expand_Pragma_Interrupt_Priority;
end Exp_Prag;