-- --
-- B o d y --
-- --
--- Copyright (C) 1992-2005 Free Software Foundation, Inc. --
+-- 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- --
with Atree; use Atree;
with Checks; use Checks;
+with Debug; use Debug;
with Einfo; use Einfo;
with Elists; use Elists;
with Errout; use Errout;
with Exp_Aggr; use Exp_Aggr;
with Exp_Ch7; use Exp_Ch7;
-with Exp_Ch11; use Exp_Ch11;
-with Exp_Tss; use Exp_Tss;
-with Hostparm; use Hostparm;
with Inline; use Inline;
with Itypes; use Itypes;
with Lib; use Lib;
-with Namet; use Namet;
with Nlists; use Nlists;
with Nmake; use Nmake;
with Opt; use Opt;
with Sem_Res; use Sem_Res;
with Sem_Type; use Sem_Type;
with Sem_Util; use Sem_Util;
-with Sinfo; use Sinfo;
with Snames; use Snames;
with Stand; use Stand;
with Stringt; use Stringt;
-- procedure of record with task components, or for a dynamically
-- created task that is assigned to a selected component.
- procedure Find_Interface_Tag
- (T : Entity_Id;
- Iface : Entity_Id;
- Iface_Tag : out Entity_Id;
- Iface_ADT : out Entity_Id);
- -- Ada 2005 (AI-251): Subsidiary procedure to Find_Interface_ADT and
- -- Find_Interface_Tag. Given a type T implementing the interface,
- -- returns the corresponding Tag and Access_Disp_Table entities.
-
function Make_CW_Equivalent_Type
(T : Entity_Id;
E : Node_Id) return Entity_Id;
--------------------------
procedure Append_Freeze_Action (T : Entity_Id; N : Node_Id) is
- Fnode : Node_Id := Freeze_Node (T);
+ Fnode : Node_Id;
begin
Ensure_Freeze_Node (T);
Fnode := Freeze_Node (T);
- if not Present (Actions (Fnode)) then
+ if No (Actions (Fnode)) then
Set_Actions (Fnode, New_List);
end if;
----------------------------
function Build_Task_Image_Decls
- (Loc : Source_Ptr;
- Id_Ref : Node_Id;
- A_Type : Entity_Id) return List_Id
+ (Loc : Source_Ptr;
+ Id_Ref : Node_Id;
+ A_Type : Entity_Id;
+ In_Init_Proc : Boolean := False) return List_Id
is
Decls : constant List_Id := New_List;
T_Id : Entity_Id := Empty;
Append (Fun, Decls);
Expr := Make_Function_Call (Loc,
Name => New_Occurrence_Of (Defining_Entity (Fun), Loc));
+
+ if not In_Init_Proc and then VM_Target = No_VM then
+ Set_Uses_Sec_Stack (Defining_Entity (Fun));
+ end if;
end if;
Decl := Make_Object_Declaration (Loc,
Spec := Make_Function_Specification (Loc,
Defining_Unit_Name =>
Make_Defining_Identifier (Loc, New_Internal_Name ('F')),
- Subtype_Mark => New_Occurrence_Of (Standard_String, Loc));
+ Result_Definition => New_Occurrence_Of (Standard_String, Loc));
-- Calls to 'Image use the secondary stack, which must be cleaned
-- up after the task name is built.
- Set_Uses_Sec_Stack (Defining_Unit_Name (Spec));
-
return Make_Subprogram_Body (Loc,
Specification => Spec,
Declarations => Decls,
-- objects which are constrained by an initial expression. Basically it
-- transforms an unconstrained subtype indication into a constrained one.
-- The expression may also be transformed in certain cases in order to
- -- avoid multiple evaulation. In the static allocation case, the general
- -- scheme is :
+ -- avoid multiple evaluation. In the static allocation case, the general
+ -- scheme is:
-- Val : T := Expr;
then
null;
+ -- Nothing to be done for derived types with unknown discriminants if
+ -- the parent type also has unknown discriminants.
+
+ elsif Is_Record_Type (Unc_Type)
+ and then not Is_Class_Wide_Type (Unc_Type)
+ and then Has_Unknown_Discriminants (Unc_Type)
+ and then Has_Unknown_Discriminants (Underlying_Type (Unc_Type))
+ then
+ null;
+
+ -- In Ada95, Nothing to be done if the type of the expression is
+ -- limited, because in this case the expression cannot be copied,
+ -- and its use can only be by reference.
+
+ -- In Ada2005, the context can be an object declaration whose expression
+ -- is a function that returns in place. If the nominal subtype has
+ -- unknown discriminants, the call still provides constraints on the
+ -- object, and we have to create an actual subtype from it.
+
+ -- If the type is class-wide, the expression is dynamically tagged and
+ -- we do not create an actual subtype either. Ditto for an interface.
+
+ elsif Is_Limited_Type (Exp_Typ)
+ and then
+ (Is_Class_Wide_Type (Exp_Typ)
+ or else Is_Interface (Exp_Typ)
+ or else not Has_Unknown_Discriminants (Exp_Typ)
+ or else not Is_Composite_Type (Unc_Type))
+ then
+ null;
+
+ -- For limited interfaces, nothing to be done
+
+ -- This branch may be redundant once the limited interface issue is
+ -- sorted out???
+
+ elsif Is_Interface (Exp_Typ)
+ and then Is_Limited_Interface (Exp_Typ)
+ then
+ null;
+
else
Remove_Side_Effects (Exp);
Rewrite (Subtype_Indic,
end Expand_Subtype_From_Expr;
------------------------
- -- Find_Interface_Tag --
+ -- Find_Interface_ADT --
------------------------
- procedure Find_Interface_Tag
- (T : Entity_Id;
- Iface : Entity_Id;
- Iface_Tag : out Entity_Id;
- Iface_ADT : out Entity_Id)
+ function Find_Interface_ADT
+ (T : Entity_Id;
+ Iface : Entity_Id) return Entity_Id
is
- AI_Tag : Entity_Id;
- ADT_Elmt : Elmt_Id;
- Found : Boolean := False;
+ ADT : Elmt_Id;
+ Found : Boolean := False;
+ Typ : Entity_Id := T;
- procedure Find_AI_Tag (Typ : in Entity_Id; Found : in out Boolean);
- -- This must be commented ???
+ procedure Find_Secondary_Table (Typ : Entity_Id);
+ -- Internal subprogram used to recursively climb to the ancestors
- -----------------
- -- Find_AI_Tag --
- -----------------
+ --------------------------
+ -- Find_Secondary_Table --
+ --------------------------
- procedure Find_AI_Tag (Typ : in Entity_Id; Found : in out Boolean) is
- T : Entity_Id := Typ;
- Etyp : Entity_Id; -- := Etype (Typ); -- why is this commented ???
+ procedure Find_Secondary_Table (Typ : Entity_Id) is
AI_Elmt : Elmt_Id;
AI : Node_Id;
begin
- -- Check if the interface is an immediate ancestor of the type and
- -- therefore shares the main tag.
+ pragma Assert (Typ /= Iface);
- if Typ = Iface then
- AI_Tag := First_Tag_Component (Typ);
- ADT_Elmt := First_Elmt (Access_Disp_Table (Typ));
- Found := True;
- return;
+ -- Climb to the ancestor (if any) handling synchronized interface
+ -- derivations and private types
+
+ if Is_Concurrent_Record_Type (Typ) then
+ declare
+ Iface_List : constant List_Id := Abstract_Interface_List (Typ);
+
+ begin
+ if Is_Non_Empty_List (Iface_List) then
+ Find_Secondary_Table (Etype (First (Iface_List)));
+ end if;
+ end;
+
+ elsif Present (Full_View (Etype (Typ))) then
+ if Full_View (Etype (Typ)) /= Typ then
+ Find_Secondary_Table (Full_View (Etype (Typ)));
+ end if;
+
+ elsif Etype (Typ) /= Typ then
+ Find_Secondary_Table (Etype (Typ));
end if;
- -- Handle private types
+ -- Traverse the list of interfaces implemented by the type
- if Has_Private_Declaration (T)
- and then Present (Full_View (T))
+ if not Found
+ and then Present (Abstract_Interfaces (Typ))
+ and then not Is_Empty_Elmt_List (Abstract_Interfaces (Typ))
then
- T := Full_View (T);
+ AI_Elmt := First_Elmt (Abstract_Interfaces (Typ));
+ while Present (AI_Elmt) loop
+ AI := Node (AI_Elmt);
+
+ if AI = Iface or else Is_Ancestor (Iface, AI) then
+ Found := True;
+ return;
+ end if;
+
+ Next_Elmt (ADT);
+ Next_Elmt (AI_Elmt);
+ end loop;
end if;
+ end Find_Secondary_Table;
- if Is_Access_Type (Typ) then
- T := Directly_Designated_Type (T);
+ -- Start of processing for Find_Interface_ADT
- elsif Ekind (T) = E_Protected_Type
- or else Ekind (T) = E_Task_Type
- then
- T := Corresponding_Record_Type (T);
+ begin
+ pragma Assert (Is_Interface (Iface));
+
+ -- Handle private types
+
+ if Has_Private_Declaration (Typ)
+ and then Present (Full_View (Typ))
+ then
+ Typ := Full_View (Typ);
+ end if;
+
+ -- Handle access types
+
+ if Is_Access_Type (Typ) then
+ Typ := Directly_Designated_Type (Typ);
+ end if;
+
+ -- Handle task and protected types implementing interfaces
+
+ if Is_Concurrent_Type (Typ) then
+ Typ := Corresponding_Record_Type (Typ);
+ end if;
+
+ pragma Assert
+ (not Is_Class_Wide_Type (Typ)
+ and then Ekind (Typ) /= E_Incomplete_Type);
+
+ ADT := Next_Elmt (First_Elmt (Access_Disp_Table (Typ)));
+ pragma Assert (Present (Node (ADT)));
+ Find_Secondary_Table (Typ);
+ pragma Assert (Found);
+ return Node (ADT);
+ end Find_Interface_ADT;
+
+ ------------------------
+ -- Find_Interface_Tag --
+ ------------------------
+
+ function Find_Interface_Tag
+ (T : Entity_Id;
+ Iface : Entity_Id) return Entity_Id
+ is
+ AI_Tag : Entity_Id;
+ Found : Boolean := False;
+ Typ : Entity_Id := T;
+
+ Is_Primary_Tag : Boolean := False;
+
+ Is_Sync_Typ : Boolean := False;
+ -- In case of non concurrent-record-types each parent-type has the
+ -- tags associated with the interface types that are not implemented
+ -- by the ancestors; concurrent-record-types have their whole list of
+ -- interface tags (and this case requires some special management).
+
+ procedure Find_Tag (Typ : Entity_Id);
+ -- Internal subprogram used to recursively climb to the ancestors
+
+ --------------
+ -- Find_Tag --
+ --------------
+
+ procedure Find_Tag (Typ : Entity_Id) is
+ AI_Elmt : Elmt_Id;
+ AI : Node_Id;
+
+ begin
+ -- Check if the interface is an immediate ancestor of the type and
+ -- therefore shares the main tag.
+
+ if Typ = Iface then
+ if Is_Sync_Typ then
+ Is_Primary_Tag := True;
+ else
+ pragma Assert
+ (Etype (First_Tag_Component (Typ)) = RTE (RE_Tag));
+ AI_Tag := First_Tag_Component (Typ);
+ end if;
+
+ Found := True;
+ return;
end if;
- Etyp := Etype (T);
+ -- Handle synchronized interface derivations
- -- Climb to the root type
+ if Is_Concurrent_Record_Type (Typ) then
+ declare
+ Iface_List : constant List_Id := Abstract_Interface_List (Typ);
+ begin
+ if Is_Non_Empty_List (Iface_List) then
+ Find_Tag (Etype (First (Iface_List)));
+ end if;
+ end;
+
+ -- Climb to the root type handling private types
- if Etyp /= Typ then
- Find_AI_Tag (Etyp, Found);
+ elsif Present (Full_View (Etype (Typ))) then
+ if Full_View (Etype (Typ)) /= Typ then
+ Find_Tag (Full_View (Etype (Typ)));
+ end if;
+
+ elsif Etype (Typ) /= Typ then
+ Find_Tag (Etype (Typ));
end if;
-- Traverse the list of interfaces implemented by the type
if not Found
- and then Present (Abstract_Interfaces (T))
- and then not Is_Empty_Elmt_List (Abstract_Interfaces (T))
+ and then Present (Abstract_Interfaces (Typ))
+ and then not (Is_Empty_Elmt_List (Abstract_Interfaces (Typ)))
then
- -- Skip the tag associated with the primary table (if
- -- already placed in the record)
+ -- Skip the tag associated with the primary table
- if Etype (Node (First_Elmt
- (Access_Disp_Table (T)))) = RTE (RE_Tag)
- then
- AI_Tag := Next_Tag_Component (First_Tag_Component (T));
- ADT_Elmt := Next_Elmt (First_Elmt (Access_Disp_Table (T)));
- else
- AI_Tag := First_Tag_Component (T);
- ADT_Elmt := First_Elmt (Access_Disp_Table (T));
+ if not Is_Sync_Typ then
+ pragma Assert
+ (Etype (First_Tag_Component (Typ)) = RTE (RE_Tag));
+ AI_Tag := Next_Tag_Component (First_Tag_Component (Typ));
+ pragma Assert (Present (AI_Tag));
end if;
- pragma Assert (Present (AI_Tag));
- pragma Assert (Present (Node (ADT_Elmt)));
-
- AI_Elmt := First_Elmt (Abstract_Interfaces (T));
+ AI_Elmt := First_Elmt (Abstract_Interfaces (Typ));
while Present (AI_Elmt) loop
AI := Node (AI_Elmt);
AI_Tag := Next_Tag_Component (AI_Tag);
Next_Elmt (AI_Elmt);
- Next_Elmt (ADT_Elmt);
end loop;
end if;
- end Find_AI_Tag;
+ end Find_Tag;
+
+ -- Start of processing for Find_Interface_Tag
begin
- Find_AI_Tag (T, Found);
- pragma Assert (Found);
+ pragma Assert (Is_Interface (Iface));
+
+ -- Handle private types
+
+ if Has_Private_Declaration (Typ)
+ and then Present (Full_View (Typ))
+ then
+ Typ := Full_View (Typ);
+ end if;
+
+ -- Handle access types
+
+ if Is_Access_Type (Typ) then
+ Typ := Directly_Designated_Type (Typ);
+ end if;
+
+ -- Handle task and protected types implementing interfaces
+
+ if Is_Concurrent_Type (Typ) then
+ Typ := Corresponding_Record_Type (Typ);
+ end if;
+
+ if Is_Class_Wide_Type (Typ) then
+ Typ := Etype (Typ);
+ end if;
+
+ -- Handle entities from the limited view
+
+ if Ekind (Typ) = E_Incomplete_Type then
+ pragma Assert (Present (Non_Limited_View (Typ)));
+ Typ := Non_Limited_View (Typ);
+ end if;
- Iface_Tag := AI_Tag;
- Iface_ADT := Node (ADT_Elmt);
+ if not Is_Concurrent_Record_Type (Typ) then
+ Find_Tag (Typ);
+ pragma Assert (Found);
+ return AI_Tag;
+
+ -- Concurrent record types
+
+ else
+ Is_Sync_Typ := True;
+ AI_Tag := Next_Tag_Component (First_Tag_Component (Typ));
+ Find_Tag (Typ);
+ pragma Assert (Found);
+
+ if Is_Primary_Tag then
+ return First_Tag_Component (Typ);
+ else
+ return AI_Tag;
+ end if;
+ end if;
end Find_Interface_Tag;
- ------------------------
- -- Find_Interface_Tag --
- ------------------------
+ --------------------
+ -- Find_Interface --
+ --------------------
- function Find_Interface_ADT
- (T : Entity_Id;
- Iface : Entity_Id) return Entity_Id
+ function Find_Interface
+ (T : Entity_Id;
+ Comp : Entity_Id) return Entity_Id
is
- Iface_Tag : Entity_Id := Empty;
- Iface_ADT : Entity_Id := Empty;
- begin
- Find_Interface_Tag (T, Iface, Iface_Tag, Iface_ADT);
- return Iface_ADT;
- end Find_Interface_ADT;
+ AI_Tag : Entity_Id;
+ Found : Boolean := False;
+ Iface : Entity_Id;
+ Typ : Entity_Id := T;
- ------------------------
- -- Find_Interface_Tag --
- ------------------------
+ Is_Sync_Typ : Boolean := False;
+ -- In case of non concurrent-record-types each parent-type has the
+ -- tags associated with the interface types that are not implemented
+ -- by the ancestors; concurrent-record-types have their whole list of
+ -- interface tags (and this case requires some special management).
+
+ procedure Find_Iface (Typ : Entity_Id);
+ -- Internal subprogram used to recursively climb to the ancestors
+
+ ----------------
+ -- Find_Iface --
+ ----------------
+
+ procedure Find_Iface (Typ : Entity_Id) is
+ AI_Elmt : Elmt_Id;
+
+ begin
+ -- Climb to the root type
+
+ -- Handle sychronized interface derivations
+
+ if Is_Concurrent_Record_Type (Typ) then
+ declare
+ Iface_List : constant List_Id := Abstract_Interface_List (Typ);
+ begin
+ if Is_Non_Empty_List (Iface_List) then
+ Find_Iface (Etype (First (Iface_List)));
+ end if;
+ end;
+
+ -- Handle the common case
+
+ elsif Etype (Typ) /= Typ then
+ pragma Assert (not Present (Full_View (Etype (Typ))));
+ Find_Iface (Etype (Typ));
+ end if;
+
+ -- Traverse the list of interfaces implemented by the type
+
+ if not Found
+ and then Present (Abstract_Interfaces (Typ))
+ and then not (Is_Empty_Elmt_List (Abstract_Interfaces (Typ)))
+ then
+ -- Skip the tag associated with the primary table
+
+ if not Is_Sync_Typ then
+ pragma Assert
+ (Etype (First_Tag_Component (Typ)) = RTE (RE_Tag));
+ AI_Tag := Next_Tag_Component (First_Tag_Component (Typ));
+ pragma Assert (Present (AI_Tag));
+ end if;
+
+ AI_Elmt := First_Elmt (Abstract_Interfaces (Typ));
+ while Present (AI_Elmt) loop
+ if AI_Tag = Comp then
+ Iface := Node (AI_Elmt);
+ Found := True;
+ return;
+ end if;
+
+ AI_Tag := Next_Tag_Component (AI_Tag);
+ Next_Elmt (AI_Elmt);
+ end loop;
+ end if;
+ end Find_Iface;
+
+ -- Start of processing for Find_Interface
- function Find_Interface_Tag
- (T : Entity_Id;
- Iface : Entity_Id) return Entity_Id
- is
- Iface_Tag : Entity_Id := Empty;
- Iface_ADT : Entity_Id := Empty;
begin
- Find_Interface_Tag (T, Iface, Iface_Tag, Iface_ADT);
- return Iface_Tag;
- end Find_Interface_Tag;
+ -- Handle private types
+
+ if Has_Private_Declaration (Typ)
+ and then Present (Full_View (Typ))
+ then
+ Typ := Full_View (Typ);
+ end if;
+
+ -- Handle access types
+
+ if Is_Access_Type (Typ) then
+ Typ := Directly_Designated_Type (Typ);
+ end if;
+
+ -- Handle task and protected types implementing interfaces
+
+ if Is_Concurrent_Type (Typ) then
+ Typ := Corresponding_Record_Type (Typ);
+ end if;
+
+ if Is_Class_Wide_Type (Typ) then
+ Typ := Etype (Typ);
+ end if;
+
+ -- Handle entities from the limited view
+
+ if Ekind (Typ) = E_Incomplete_Type then
+ pragma Assert (Present (Non_Limited_View (Typ)));
+ Typ := Non_Limited_View (Typ);
+ end if;
+
+ if Is_Concurrent_Record_Type (Typ) then
+ Is_Sync_Typ := True;
+ AI_Tag := Next_Tag_Component (First_Tag_Component (Typ));
+ end if;
+
+ Find_Iface (Typ);
+ pragma Assert (Found);
+ return Iface;
+ end Find_Interface;
------------------
-- Find_Prim_Op --
function Find_Prim_Op (T : Entity_Id; Name : Name_Id) return Entity_Id is
Prim : Elmt_Id;
Typ : Entity_Id := T;
+ Op : Entity_Id;
begin
if Is_Class_Wide_Type (Typ) then
Typ := Underlying_Type (Typ);
+ -- Loop through primitive operations
+
Prim := First_Elmt (Primitive_Operations (Typ));
- while Chars (Node (Prim)) /= Name loop
+ while Present (Prim) loop
+ Op := Node (Prim);
+
+ -- We can retrieve primitive operations by name if it is an internal
+ -- name. For equality we must check that both of its operands have
+ -- the same type, to avoid confusion with user-defined equalities
+ -- than may have a non-symmetric signature.
+
+ exit when Chars (Op) = Name
+ and then
+ (Name /= Name_Op_Eq
+ or else Etype (First_Entity (Op)) = Etype (Last_Entity (Op)));
+
Next_Elmt (Prim);
pragma Assert (Present (Prim));
end loop;
return Node (Prim);
end Find_Prim_Op;
+ ------------------
+ -- Find_Prim_Op --
+ ------------------
+
function Find_Prim_Op
(T : Entity_Id;
Name : TSS_Name_Type) return Entity_Id
-- Get_Current_Value_Condition --
---------------------------------
+ -- Note: the implementation of this procedure is very closely tied to the
+ -- implementation of Set_Current_Value_Condition. In the Get procedure, we
+ -- interpret Current_Value fields set by the Set procedure, so the two
+ -- procedures need to be closely coordinated.
+
procedure Get_Current_Value_Condition
(Var : Node_Id;
Op : out Node_Kind;
Val : out Node_Id)
is
- Loc : constant Source_Ptr := Sloc (Var);
- CV : constant Node_Id := Current_Value (Entity (Var));
- Sens : Boolean;
- Stm : Node_Id;
- Cond : Node_Id;
+ Loc : constant Source_Ptr := Sloc (Var);
+ Ent : constant Entity_Id := Entity (Var);
+
+ procedure Process_Current_Value_Condition
+ (N : Node_Id;
+ S : Boolean);
+ -- N is an expression which holds either True (S = True) or False (S =
+ -- False) in the condition. This procedure digs out the expression and
+ -- if it refers to Ent, sets Op and Val appropriately.
+
+ -------------------------------------
+ -- Process_Current_Value_Condition --
+ -------------------------------------
+
+ procedure Process_Current_Value_Condition
+ (N : Node_Id;
+ S : Boolean)
+ is
+ Cond : Node_Id;
+ Sens : Boolean;
- begin
- Op := N_Empty;
- Val := Empty;
+ begin
+ Cond := N;
+ Sens := S;
- -- If statement. Condition is known true in THEN section, known False
- -- in any ELSIF or ELSE part, and unknown outside the IF statement.
+ -- Deal with NOT operators, inverting sense
- if Nkind (CV) = N_If_Statement then
+ while Nkind (Cond) = N_Op_Not loop
+ Cond := Right_Opnd (Cond);
+ Sens := not Sens;
+ end loop;
- -- Before start of IF statement
+ -- Deal with AND THEN and AND cases
- if Loc < Sloc (CV) then
- return;
+ if Nkind (Cond) = N_And_Then
+ or else Nkind (Cond) = N_Op_And
+ then
+ -- Don't ever try to invert a condition that is of the form
+ -- of an AND or AND THEN (since we are not doing sufficiently
+ -- general processing to allow this).
+
+ if Sens = False then
+ Op := N_Empty;
+ Val := Empty;
+ return;
+ end if;
+
+ -- Recursively process AND and AND THEN branches
- -- After end of IF statement
+ Process_Current_Value_Condition (Left_Opnd (Cond), True);
- elsif Loc >= Sloc (CV) + Text_Ptr (UI_To_Int (End_Span (CV))) then
+ if Op /= N_Empty then
+ return;
+ end if;
+
+ Process_Current_Value_Condition (Right_Opnd (Cond), True);
return;
- end if;
- -- At this stage we know that we are within the IF statement, but
- -- unfortunately, the tree does not record the SLOC of the ELSE so
- -- we cannot use a simple SLOC comparison to distinguish between
- -- the then/else statements, so we have to climb the tree.
+ -- Case of relational operator
- declare
- N : Node_Id;
+ elsif Nkind (Cond) in N_Op_Compare then
+ Op := Nkind (Cond);
- begin
- N := Parent (Var);
- while Parent (N) /= CV loop
- N := Parent (N);
+ -- Invert sense of test if inverted test
- -- If we fall off the top of the tree, then that's odd, but
- -- perhaps it could occur in some error situation, and the
- -- safest response is simply to assume that the outcome of the
- -- condition is unknown. No point in bombing during an attempt
- -- to optimize things.
+ if Sens = False then
+ case Op is
+ when N_Op_Eq => Op := N_Op_Ne;
+ when N_Op_Ne => Op := N_Op_Eq;
+ when N_Op_Lt => Op := N_Op_Ge;
+ when N_Op_Gt => Op := N_Op_Le;
+ when N_Op_Le => Op := N_Op_Gt;
+ when N_Op_Ge => Op := N_Op_Lt;
+ when others => raise Program_Error;
+ end case;
+ end if;
- if No (N) then
- return;
- end if;
- end loop;
+ -- Case of entity op value
- -- Now we have N pointing to a node whose parent is the IF
- -- statement in question, so now we can tell if we are within
- -- the THEN statements.
+ if Is_Entity_Name (Left_Opnd (Cond))
+ and then Ent = Entity (Left_Opnd (Cond))
+ and then Compile_Time_Known_Value (Right_Opnd (Cond))
+ then
+ Val := Right_Opnd (Cond);
+
+ -- Case of value op entity
- if Is_List_Member (N)
- and then List_Containing (N) = Then_Statements (CV)
+ elsif Is_Entity_Name (Right_Opnd (Cond))
+ and then Ent = Entity (Right_Opnd (Cond))
+ and then Compile_Time_Known_Value (Left_Opnd (Cond))
then
- Sens := True;
+ Val := Left_Opnd (Cond);
+
+ -- We are effectively swapping operands
- -- Otherwise we must be in ELSIF or ELSE part
+ case Op is
+ when N_Op_Eq => null;
+ when N_Op_Ne => null;
+ when N_Op_Lt => Op := N_Op_Gt;
+ when N_Op_Gt => Op := N_Op_Lt;
+ when N_Op_Le => Op := N_Op_Ge;
+ when N_Op_Ge => Op := N_Op_Le;
+ when others => raise Program_Error;
+ end case;
else
- Sens := False;
+ Op := N_Empty;
end if;
- end;
- -- ELSIF part. Condition is known true within the referenced ELSIF,
- -- known False in any subsequent ELSIF or ELSE part, and unknown before
- -- the ELSE part or after the IF statement.
+ return;
- elsif Nkind (CV) = N_Elsif_Part then
- Stm := Parent (CV);
+ -- Case of Boolean variable reference, return as though the
+ -- reference had said var = True.
- -- Before start of ELSIF part
+ else
+ if Is_Entity_Name (Cond)
+ and then Ent = Entity (Cond)
+ then
+ Val := New_Occurrence_Of (Standard_True, Sloc (Cond));
- if Loc < Sloc (CV) then
- return;
+ if Sens = False then
+ Op := N_Op_Ne;
+ else
+ Op := N_Op_Eq;
+ end if;
+ end if;
+ end if;
+ end Process_Current_Value_Condition;
- -- After end of IF statement
+ -- Start of processing for Get_Current_Value_Condition
- elsif Loc >= Sloc (Stm) +
- Text_Ptr (UI_To_Int (End_Span (Stm)))
- then
- return;
- end if;
+ begin
+ Op := N_Empty;
+ Val := Empty;
- -- Again we lack the SLOC of the ELSE, so we need to climb the tree
- -- to see if we are within the ELSIF part in question.
+ -- Immediate return, nothing doing, if this is not an object
- declare
- N : Node_Id;
+ if Ekind (Ent) not in Object_Kind then
+ return;
+ end if;
- begin
- N := Parent (Var);
- while Parent (N) /= Stm loop
- N := Parent (N);
+ -- Otherwise examine current value
+
+ declare
+ CV : constant Node_Id := Current_Value (Ent);
+ Sens : Boolean;
+ Stm : Node_Id;
+
+ begin
+ -- If statement. Condition is known true in THEN section, known False
+ -- in any ELSIF or ELSE part, and unknown outside the IF statement.
- -- If we fall off the top of the tree, then that's odd, but
- -- perhaps it could occur in some error situation, and the
- -- safest response is simply to assume that the outcome of the
- -- condition is unknown. No point in bombing during an attempt
- -- to optimize things.
+ if Nkind (CV) = N_If_Statement then
+
+ -- Before start of IF statement
+
+ if Loc < Sloc (CV) then
+ return;
+
+ -- After end of IF statement
+
+ elsif Loc >= Sloc (CV) + Text_Ptr (UI_To_Int (End_Span (CV))) then
+ return;
+ end if;
+
+ -- At this stage we know that we are within the IF statement, but
+ -- unfortunately, the tree does not record the SLOC of the ELSE so
+ -- we cannot use a simple SLOC comparison to distinguish between
+ -- the then/else statements, so we have to climb the tree.
+
+ declare
+ N : Node_Id;
- if No (N) then
+ begin
+ N := Parent (Var);
+ while Parent (N) /= CV loop
+ N := Parent (N);
+
+ -- If we fall off the top of the tree, then that's odd, but
+ -- perhaps it could occur in some error situation, and the
+ -- safest response is simply to assume that the outcome of
+ -- the condition is unknown. No point in bombing during an
+ -- attempt to optimize things.
+
+ if No (N) then
+ return;
+ end if;
+ end loop;
+
+ -- Now we have N pointing to a node whose parent is the IF
+ -- statement in question, so now we can tell if we are within
+ -- the THEN statements.
+
+ if Is_List_Member (N)
+ and then List_Containing (N) = Then_Statements (CV)
+ then
+ Sens := True;
+
+ -- If the variable reference does not come from source, we
+ -- cannot reliably tell whether it appears in the else part.
+ -- In particular, if if appears in generated code for a node
+ -- that requires finalization, it may be attached to a list
+ -- that has not been yet inserted into the code. For now,
+ -- treat it as unknown.
+
+ elsif not Comes_From_Source (N) then
return;
+
+ -- Otherwise we must be in ELSIF or ELSE part
+
+ else
+ Sens := False;
end if;
- end loop;
+ end;
- -- Now we have N pointing to a node whose parent is the IF
- -- statement in question, so see if is the ELSIF part we want.
- -- the THEN statements.
+ -- ELSIF part. Condition is known true within the referenced
+ -- ELSIF, known False in any subsequent ELSIF or ELSE part, and
+ -- unknown before the ELSE part or after the IF statement.
- if N = CV then
- Sens := True;
+ elsif Nkind (CV) = N_Elsif_Part then
+ Stm := Parent (CV);
- -- Otherwise we must be in susbequent ELSIF or ELSE part
+ -- Before start of ELSIF part
- else
- Sens := False;
+ if Loc < Sloc (CV) then
+ return;
+
+ -- After end of IF statement
+
+ elsif Loc >= Sloc (Stm) +
+ Text_Ptr (UI_To_Int (End_Span (Stm)))
+ then
+ return;
end if;
- end;
- -- All other cases of Current_Value settings
+ -- Again we lack the SLOC of the ELSE, so we need to climb the
+ -- tree to see if we are within the ELSIF part in question.
- else
- return;
- end if;
+ declare
+ N : Node_Id;
+
+ begin
+ N := Parent (Var);
+ while Parent (N) /= Stm loop
+ N := Parent (N);
+
+ -- If we fall off the top of the tree, then that's odd, but
+ -- perhaps it could occur in some error situation, and the
+ -- safest response is simply to assume that the outcome of
+ -- the condition is unknown. No point in bombing during an
+ -- attempt to optimize things.
+
+ if No (N) then
+ return;
+ end if;
+ end loop;
+
+ -- Now we have N pointing to a node whose parent is the IF
+ -- statement in question, so see if is the ELSIF part we want.
+ -- the THEN statements.
+
+ if N = CV then
+ Sens := True;
+
+ -- Otherwise we must be in susbequent ELSIF or ELSE part
+
+ else
+ Sens := False;
+ end if;
+ end;
+
+ -- Iteration scheme of while loop. The condition is known to be
+ -- true within the body of the loop.
+
+ elsif Nkind (CV) = N_Iteration_Scheme then
+ declare
+ Loop_Stmt : constant Node_Id := Parent (CV);
+
+ begin
+ -- Before start of body of loop
+
+ if Loc < Sloc (Loop_Stmt) then
+ return;
+
+ -- After end of LOOP statement
+
+ elsif Loc >= Sloc (End_Label (Loop_Stmt)) then
+ return;
+
+ -- We are within the body of the loop
+
+ else
+ Sens := True;
+ end if;
+ end;
+
+ -- All other cases of Current_Value settings
+
+ else
+ return;
+ end if;
- -- If we fall through here, then we have a reportable condition, Sens is
- -- True if the condition is true and False if it needs inverting.
+ -- If we fall through here, then we have a reportable condition, Sens
+ -- is True if the condition is true and False if it needs inverting.
- -- Deal with NOT operators, inverting sense
+ Process_Current_Value_Condition (Condition (CV), Sens);
+ end;
+ end Get_Current_Value_Condition;
- Cond := Condition (CV);
- while Nkind (Cond) = N_Op_Not loop
- Cond := Right_Opnd (Cond);
- Sens := not Sens;
- end loop;
+ ---------------------------------
+ -- Has_Controlled_Coextensions --
+ ---------------------------------
+
+ function Has_Controlled_Coextensions (Typ : Entity_Id) return Boolean is
+ D_Typ : Entity_Id;
+ Discr : Entity_Id;
- -- Now we must have a relational operator
+ begin
+ -- Only consider record types
- pragma Assert (Entity (Var) = Entity (Left_Opnd (Cond)));
- Val := Right_Opnd (Cond);
- Op := Nkind (Cond);
+ if Ekind (Typ) /= E_Record_Type
+ and then Ekind (Typ) /= E_Record_Subtype
+ then
+ return False;
+ end if;
- if Sens = False then
- case Op is
- when N_Op_Eq => Op := N_Op_Ne;
- when N_Op_Ne => Op := N_Op_Eq;
- when N_Op_Lt => Op := N_Op_Ge;
- when N_Op_Gt => Op := N_Op_Le;
- when N_Op_Le => Op := N_Op_Gt;
- when N_Op_Ge => Op := N_Op_Lt;
+ if Has_Discriminants (Typ) then
+ Discr := First_Discriminant (Typ);
+ while Present (Discr) loop
+ D_Typ := Etype (Discr);
- -- No other entry should be possible
+ if Ekind (D_Typ) = E_Anonymous_Access_Type
+ and then
+ (Is_Controlled (Directly_Designated_Type (D_Typ))
+ or else
+ Is_Concurrent_Type (Directly_Designated_Type (D_Typ)))
+ then
+ return True;
+ end if;
- when others =>
- raise Program_Error;
- end case;
+ Next_Discriminant (Discr);
+ end loop;
end if;
- end Get_Current_Value_Condition;
+
+ return False;
+ end Has_Controlled_Coextensions;
--------------------
-- Homonym_Number --
-- Capture root of the transient scope
if Scope_Is_Transient then
- Wrapped_Node := Node_To_Be_Wrapped;
+ Wrapped_Node := Node_To_Be_Wrapped;
end if;
loop
null;
-- Do not insert if parent of P is an N_Component_Association
- -- node (i.e. we are in the context of an N_Aggregate node.
- -- In this case we want to insert before the entire aggregate.
+ -- node (i.e. we are in the context of an N_Aggregate or
+ -- N_Extension_Aggregate node. In this case we want to insert
+ -- before the entire aggregate.
elsif Nkind (Parent (P)) = N_Component_Association then
null;
-- Otherwise we can go ahead and do the insertion
- elsif P = Wrapped_Node then
+ elsif P = Wrapped_Node then
Store_Before_Actions_In_Scope (Ins_Actions);
return;
N_Package_Specification |
N_Parameter_Association |
N_Parameter_Specification |
+ N_Pop_Constraint_Error_Label |
+ N_Pop_Program_Error_Label |
+ N_Pop_Storage_Error_Label |
N_Pragma_Argument_Association |
N_Procedure_Specification |
N_Protected_Body |
N_Protected_Definition |
+ N_Push_Constraint_Error_Label |
+ N_Push_Program_Error_Label |
+ N_Push_Storage_Error_Label |
N_Qualified_Expression |
N_Range |
N_Range_Constraint |
N_Variant |
N_Variant_Part |
N_Validate_Unchecked_Conversion |
- N_With_Clause |
- N_With_Type_Clause
+ N_With_Clause
=>
null;
P := Parent (N);
end if;
end loop;
-
end Insert_Actions;
-- Version with check(s) suppressed
procedure Insert_Actions
- (Assoc_Node : Node_Id; Ins_Actions : List_Id; Suppress : Check_Id)
+ (Assoc_Node : Node_Id;
+ Ins_Actions : List_Id;
+ Suppress : Check_Id)
is
begin
if Suppress = All_Checks then
declare
Svg : constant Suppress_Array := Scope_Suppress;
-
begin
Scope_Suppress := (others => True);
Insert_Actions (Assoc_Node, Ins_Actions);
else
declare
Svg : constant Boolean := Scope_Suppress (Suppress);
-
begin
Scope_Suppress (Suppress) := True;
Insert_Actions (Assoc_Node, Ins_Actions);
Aux : constant Node_Id := Aux_Decls_Node (Cunit (Main_Unit));
begin
- New_Scope (Cunit_Entity (Main_Unit));
+ Push_Scope (Cunit_Entity (Main_Unit));
+ -- ??? should this be Current_Sem_Unit instead of Main_Unit?
if No (Actions (Aux)) then
Set_Actions (Aux, New_List (N));
begin
if Is_Non_Empty_List (L) then
- New_Scope (Cunit_Entity (Main_Unit));
+ Push_Scope (Cunit_Entity (Main_Unit));
+ -- ??? should this be Current_Sem_Unit instead of Main_Unit?
if No (Actions (Aux)) then
Set_Actions (Aux, L);
return True;
end Is_All_Null_Statements;
- ------------------------
- -- Is_Default_Prim_Op --
- ------------------------
+ -----------------------------------------
+ -- Is_Predefined_Dispatching_Operation --
+ -----------------------------------------
- function Is_Predefined_Dispatching_Operation
- (Subp : Entity_Id) return Boolean
+ function Is_Predefined_Dispatching_Operation (E : Entity_Id) return Boolean
is
TSS_Name : TSS_Name_Type;
- E : Entity_Id := Subp;
- begin
- pragma Assert (Is_Dispatching_Operation (Subp));
-
- -- Handle overriden subprograms
- while Present (Alias (E)) loop
- E := Alias (E);
- end loop;
+ begin
+ if not Is_Dispatching_Operation (E) then
+ return False;
+ end if;
Get_Name_String (Chars (E));
or else TSS_Name = TSS_Stream_Write
or else TSS_Name = TSS_Stream_Input
or else TSS_Name = TSS_Stream_Output
- or else Chars (E) = Name_Op_Eq
+ or else
+ (Chars (E) = Name_Op_Eq
+ and then Etype (First_Entity (E)) = Etype (Last_Entity (E)))
or else Chars (E) = Name_uAssign
or else TSS_Name = TSS_Deep_Adjust
or else TSS_Name = TSS_Deep_Finalize
+ or else (Ada_Version >= Ada_05
+ and then (Chars (E) = Name_uDisp_Asynchronous_Select
+ or else Chars (E) = Name_uDisp_Conditional_Select
+ or else Chars (E) = Name_uDisp_Get_Prim_Op_Kind
+ or else Chars (E) = Name_uDisp_Get_Task_Id
+ or else Chars (E) = Name_uDisp_Timed_Select))
then
return True;
end if;
function Is_Possibly_Unaligned_Slice (N : Node_Id) return Boolean is
begin
- -- ??? GCC3 will eventually handle strings with arbitrary alignments,
- -- but for now the following check must be disabled.
-
- -- if get_gcc_version >= 3 then
- -- return False;
- -- end if;
-
- -- For renaming case, go to renamed object
+ -- Go to renamed object
if Is_Entity_Name (N)
and then Is_Object (Entity (N))
function Is_Ref_To_Bit_Packed_Slice (N : Node_Id) return Boolean is
begin
- if Is_Entity_Name (N)
+ if Nkind (N) = N_Type_Conversion then
+ return Is_Ref_To_Bit_Packed_Slice (Expression (N));
+
+ elsif Is_Entity_Name (N)
and then Is_Object (Entity (N))
and then Present (Renamed_Object (Entity (N)))
then
return Is_Ref_To_Bit_Packed_Slice (Renamed_Object (Entity (N)));
- end if;
- if Nkind (N) = N_Slice
+ elsif Nkind (N) = N_Slice
and then Is_Bit_Packed_Array (Etype (Prefix (N)))
then
return True;
and then not Is_Tagged_Type (Full_View (T))
and then Is_Derived_Type (Full_View (T))
and then Etype (Full_View (T)) /= T);
-
end Is_Untagged_Derivation;
--------------------
-- Kill_Dead_Code --
--------------------
- procedure Kill_Dead_Code (N : Node_Id) is
+ procedure Kill_Dead_Code (N : Node_Id; Warn : Boolean := False) is
begin
if Present (N) then
- Remove_Handler_Entries (N);
Remove_Warning_Messages (N);
+ if Warn then
+ Error_Msg_F
+ ("?this code can never be executed and has been deleted", N);
+ end if;
+
-- Recurse into block statements and bodies to process declarations
-- and statements
or else Nkind (N) = N_Subprogram_Body
or else Nkind (N) = N_Package_Body
then
- Kill_Dead_Code (Declarations (N));
- Kill_Dead_Code (Statements (Handled_Statement_Sequence (N)));
+ Kill_Dead_Code
+ (Declarations (N), False);
+ Kill_Dead_Code
+ (Statements (Handled_Statement_Sequence (N)));
if Nkind (N) = N_Subprogram_Body then
Set_Is_Eliminated (Defining_Entity (N));
-- Case where argument is a list of nodes to be killed
- procedure Kill_Dead_Code (L : List_Id) is
+ procedure Kill_Dead_Code (L : List_Id; Warn : Boolean := False) is
N : Node_Id;
-
+ W : Boolean;
begin
+ W := Warn;
if Is_Non_Empty_List (L) then
loop
N := Remove_Head (L);
exit when No (N);
- Kill_Dead_Code (N);
+ Kill_Dead_Code (N, W);
+ W := False;
end loop;
end if;
end Kill_Dead_Code;
function Known_Non_Null (N : Node_Id) return Boolean is
begin
- pragma Assert (Is_Access_Type (Underlying_Type (Etype (N))));
+ -- Checks for case where N is an entity reference
- -- Case of entity for which Is_Known_Non_Null is True
+ if Is_Entity_Name (N) and then Present (Entity (N)) then
+ declare
+ E : constant Entity_Id := Entity (N);
+ Op : Node_Kind;
+ Val : Node_Id;
- if Is_Entity_Name (N) and then Is_Known_Non_Null (Entity (N)) then
+ begin
+ -- First check if we are in decisive conditional
- -- If the entity is aliased or volatile, then we decide that
- -- we don't know it is really non-null even if the sequential
- -- flow indicates that it is, since such variables can be
- -- changed without us noticing.
+ Get_Current_Value_Condition (N, Op, Val);
- if Is_Aliased (Entity (N))
- or else Treat_As_Volatile (Entity (N))
- then
- return False;
+ if Nkind (Val) = N_Null then
+ if Op = N_Op_Eq then
+ return False;
+ elsif Op = N_Op_Ne then
+ return True;
+ end if;
+ end if;
- -- For all other cases, the flag is decisive
+ -- If OK to do replacement, test Is_Known_Non_Null flag
- else
- return True;
- end if;
+ if OK_To_Do_Constant_Replacement (E) then
+ return Is_Known_Non_Null (E);
+
+ -- Otherwise if not safe to do replacement, then say so
+
+ else
+ return False;
+ end if;
+ end;
-- True if access attribute
elsif Nkind (N) = N_Type_Conversion then
return Known_Non_Null (Expression (N));
- -- One more case is when Current_Value references a condition
- -- that ensures a non-null value.
+ -- Above are all cases where the value could be determined to be
+ -- non-null. In all other cases, we don't know, so return False.
+
+ else
+ return False;
+ end if;
+ end Known_Non_Null;
+
+ ----------------
+ -- Known_Null --
+ ----------------
+
+ function Known_Null (N : Node_Id) return Boolean is
+ begin
+ -- Checks for case where N is an entity reference
- elsif Is_Entity_Name (N) then
+ if Is_Entity_Name (N) and then Present (Entity (N)) then
declare
+ E : constant Entity_Id := Entity (N);
Op : Node_Kind;
Val : Node_Id;
begin
+ -- First check if we are in decisive conditional
+
Get_Current_Value_Condition (N, Op, Val);
- return Op = N_Op_Ne and then Nkind (Val) = N_Null;
+
+ if Nkind (Val) = N_Null then
+ if Op = N_Op_Eq then
+ return True;
+ elsif Op = N_Op_Ne then
+ return False;
+ end if;
+ end if;
+
+ -- If OK to do replacement, test Is_Known_Null flag
+
+ if OK_To_Do_Constant_Replacement (E) then
+ return Is_Known_Null (E);
+
+ -- Otherwise if not safe to do replacement, then say so
+
+ else
+ return False;
+ end if;
end;
- -- Above are all cases where the value could be determined to be
- -- non-null. In all other cases, we don't know, so return False.
+ -- True if explicit reference to null
+
+ elsif Nkind (N) = N_Null then
+ return True;
+
+ -- For a conversion, true if expression is known null
+
+ elsif Nkind (N) = N_Type_Conversion then
+ return Known_Null (Expression (N));
+
+ -- Above are all cases where the value could be determined to be null.
+ -- In all other cases, we don't know, so return False.
else
return False;
end if;
- end Known_Non_Null;
+ end Known_Null;
-----------------------------
-- Make_CW_Equivalent_Type --
Loc : constant Source_Ptr := Sloc (E);
Root_Typ : constant Entity_Id := Root_Type (T);
List_Def : constant List_Id := Empty_List;
+ Comp_List : constant List_Id := New_List;
Equiv_Type : Entity_Id;
Range_Type : Entity_Id;
Str_Type : Entity_Id;
Make_Subtype_From_Expr (E, Root_Typ)));
end if;
- -- subtype rg__xx is Storage_Offset range
- -- (Expr'size - typ'size) / Storage_Unit
+ -- Generate the range subtype declaration
Range_Type := Make_Defining_Identifier (Loc, New_Internal_Name ('G'));
- Sizexpr :=
- Make_Op_Subtract (Loc,
- Left_Opnd =>
- Make_Attribute_Reference (Loc,
- Prefix =>
- OK_Convert_To (T, Duplicate_Subexpr_No_Checks (E)),
- Attribute_Name => Name_Size),
- Right_Opnd =>
- Make_Attribute_Reference (Loc,
- Prefix => New_Reference_To (Constr_Root, Loc),
- Attribute_Name => Name_Object_Size));
+ if not Is_Interface (Root_Typ) then
+ -- subtype rg__xx is
+ -- Storage_Offset range 1 .. (Expr'size - typ'size) / Storage_Unit
+
+ Sizexpr :=
+ Make_Op_Subtract (Loc,
+ Left_Opnd =>
+ Make_Attribute_Reference (Loc,
+ Prefix =>
+ OK_Convert_To (T, Duplicate_Subexpr_No_Checks (E)),
+ Attribute_Name => Name_Size),
+ Right_Opnd =>
+ Make_Attribute_Reference (Loc,
+ Prefix => New_Reference_To (Constr_Root, Loc),
+ Attribute_Name => Name_Object_Size));
+ else
+ -- subtype rg__xx is
+ -- Storage_Offset range 1 .. Expr'size / Storage_Unit
+
+ Sizexpr :=
+ Make_Attribute_Reference (Loc,
+ Prefix =>
+ OK_Convert_To (T, Duplicate_Subexpr_No_Checks (E)),
+ Attribute_Name => Name_Size);
+ end if;
Set_Paren_Count (Sizexpr, 1);
New_List (New_Reference_To (Range_Type, Loc))))));
-- type Equiv_T is record
- -- _parent : Tnn;
+ -- [ _parent : Tnn; ]
-- E : Str_Type;
-- end Equiv_T;
Set_Ekind (Equiv_Type, E_Record_Type);
Set_Parent_Subtype (Equiv_Type, Constr_Root);
+ if not Is_Interface (Root_Typ) then
+ Append_To (Comp_List,
+ Make_Component_Declaration (Loc,
+ Defining_Identifier =>
+ Make_Defining_Identifier (Loc, Name_uParent),
+ Component_Definition =>
+ Make_Component_Definition (Loc,
+ Aliased_Present => False,
+ Subtype_Indication => New_Reference_To (Constr_Root, Loc))));
+ end if;
+
+ Append_To (Comp_List,
+ Make_Component_Declaration (Loc,
+ Defining_Identifier =>
+ Make_Defining_Identifier (Loc,
+ Chars => New_Internal_Name ('C')),
+ Component_Definition =>
+ Make_Component_Definition (Loc,
+ Aliased_Present => False,
+ Subtype_Indication => New_Reference_To (Str_Type, Loc))));
+
Append_To (List_Def,
Make_Full_Type_Declaration (Loc,
Defining_Identifier => Equiv_Type,
-
Type_Definition =>
Make_Record_Definition (Loc,
- Component_List => Make_Component_List (Loc,
- Component_Items => New_List (
- Make_Component_Declaration (Loc,
- Defining_Identifier =>
- Make_Defining_Identifier (Loc, Name_uParent),
- Component_Definition =>
- Make_Component_Definition (Loc,
- Aliased_Present => False,
- Subtype_Indication =>
- New_Reference_To (Constr_Root, Loc))),
-
- Make_Component_Declaration (Loc,
- Defining_Identifier =>
- Make_Defining_Identifier (Loc,
- Chars => New_Internal_Name ('C')),
- Component_Definition =>
- Make_Component_Definition (Loc,
- Aliased_Present => False,
- Subtype_Indication =>
- New_Reference_To (Str_Type, Loc)))),
-
- Variant_Part => Empty))));
-
- Insert_Actions (E, List_Def);
+ Component_List =>
+ Make_Component_List (Loc,
+ Component_Items => Comp_List,
+ Variant_Part => Empty))));
+
+ -- Suppress all checks during the analysis of the expanded code
+ -- to avoid the generation of spurious warnings under ZFP run-time.
+
+ Insert_Actions (E, List_Def, Suppress => All_Checks);
return Equiv_Type;
end Make_CW_Equivalent_Type;
and then Has_Unknown_Discriminants (Unc_Typ)
then
-- Prepare the subtype completion, Go to base type to
- -- find underlying type.
+ -- find underlying type, because the type may be a generic
+ -- actual or an explicit subtype.
Utyp := Underlying_Type (Base_Type (Unc_Typ));
Full_Subtyp := Make_Defining_Identifier (Loc,
-- Define the dummy private subtype
Set_Ekind (Priv_Subtyp, Subtype_Kind (Ekind (Unc_Typ)));
- Set_Etype (Priv_Subtyp, Unc_Typ);
+ Set_Etype (Priv_Subtyp, Base_Type (Unc_Typ));
Set_Scope (Priv_Subtyp, Full_Subtyp);
Set_Is_Constrained (Priv_Subtyp);
Set_Is_Tagged_Type (Priv_Subtyp, Is_Tagged_Type (Unc_Typ));
EQ_Typ : Entity_Id := Empty;
begin
- -- A class-wide equivalent type is not needed when Java_VM
- -- because the JVM back end handles the class-wide object
+ -- A class-wide equivalent type is not needed when VM_Target
+ -- because the VM back-ends handle the class-wide object
-- initialization itself (and doesn't need or want the
-- additional intermediate type to handle the assignment).
- if Expander_Active and then not Java_VM then
+ if Expander_Active and then VM_Target = No_VM then
EQ_Typ := Make_CW_Equivalent_Type (Unc_Typ, E);
end if;
return New_Occurrence_Of (CW_Subtype, Loc);
end;
- -- Comment needed (what case is this ???)
+ -- Indefinite record type with discriminants
else
D := First_Discriminant (Unc_Typ);
begin
Copy_Node (CW_Typ, Res);
+ Set_Comes_From_Source (Res, False);
Set_Sloc (Res, Sloc (N));
Set_Is_Itype (Res);
Set_Associated_Node_For_Itype (Res, N);
return (Res);
end New_Class_Wide_Subtype;
+ --------------------------------
+ -- Non_Limited_Designated_Type --
+ ---------------------------------
+
+ function Non_Limited_Designated_Type (T : Entity_Id) return Entity_Id is
+ Desig : constant Entity_Id := Designated_Type (T);
+ begin
+ if Ekind (Desig) = E_Incomplete_Type
+ and then Present (Non_Limited_View (Desig))
+ then
+ return Non_Limited_View (Desig);
+ else
+ return Desig;
+ end if;
+ end Non_Limited_Designated_Type;
+
+ -----------------------------------
+ -- OK_To_Do_Constant_Replacement --
+ -----------------------------------
+
+ function OK_To_Do_Constant_Replacement (E : Entity_Id) return Boolean is
+ ES : constant Entity_Id := Scope (E);
+ CS : Entity_Id;
+
+ begin
+ -- Do not replace statically allocated objects, because they may be
+ -- modified outside the current scope.
+
+ if Is_Statically_Allocated (E) then
+ return False;
+
+ -- Do not replace aliased or volatile objects, since we don't know what
+ -- else might change the value.
+
+ elsif Is_Aliased (E) or else Treat_As_Volatile (E) then
+ return False;
+
+ -- Debug flag -gnatdM disconnects this optimization
+
+ elsif Debug_Flag_MM then
+ return False;
+
+ -- Otherwise check scopes
+
+ else
+ CS := Current_Scope;
+
+ loop
+ -- If we are in right scope, replacement is safe
+
+ if CS = ES then
+ return True;
+
+ -- Packages do not affect the determination of safety
+
+ elsif Ekind (CS) = E_Package then
+ exit when CS = Standard_Standard;
+ CS := Scope (CS);
+
+ -- Blocks do not affect the determination of safety
+
+ elsif Ekind (CS) = E_Block then
+ CS := Scope (CS);
+
+ -- Loops do not affect the determination of safety. Note that we
+ -- kill all current values on entry to a loop, so we are just
+ -- talking about processing within a loop here.
+
+ elsif Ekind (CS) = E_Loop then
+ CS := Scope (CS);
+
+ -- Otherwise, the reference is dubious, and we cannot be sure that
+ -- it is safe to do the replacement.
+
+ else
+ exit;
+ end if;
+ end loop;
+
+ return False;
+ end if;
+ end OK_To_Do_Constant_Replacement;
+
+ ------------------------------------
+ -- Possible_Bit_Aligned_Component --
+ ------------------------------------
+
+ function Possible_Bit_Aligned_Component (N : Node_Id) return Boolean is
+ begin
+ case Nkind (N) is
+
+ -- Case of indexed component
+
+ when N_Indexed_Component =>
+ declare
+ P : constant Node_Id := Prefix (N);
+ Ptyp : constant Entity_Id := Etype (P);
+
+ begin
+ -- If we know the component size and it is less than 64, then
+ -- we are definitely OK. The back end always does assignment
+ -- of misaligned small objects correctly.
+
+ if Known_Static_Component_Size (Ptyp)
+ and then Component_Size (Ptyp) <= 64
+ then
+ return False;
+
+ -- Otherwise, we need to test the prefix, to see if we are
+ -- indexing from a possibly unaligned component.
+
+ else
+ return Possible_Bit_Aligned_Component (P);
+ end if;
+ end;
+
+ -- Case of selected component
+
+ when N_Selected_Component =>
+ declare
+ P : constant Node_Id := Prefix (N);
+ Comp : constant Entity_Id := Entity (Selector_Name (N));
+
+ begin
+ -- If there is no component clause, then we are in the clear
+ -- since the back end will never misalign a large component
+ -- unless it is forced to do so. In the clear means we need
+ -- only the recursive test on the prefix.
+
+ if Component_May_Be_Bit_Aligned (Comp) then
+ return True;
+ else
+ return Possible_Bit_Aligned_Component (P);
+ end if;
+ end;
+
+ -- If we have neither a record nor array component, it means that we
+ -- have fallen off the top testing prefixes recursively, and we now
+ -- have a stand alone object, where we don't have a problem.
+
+ when others =>
+ return False;
+
+ end case;
+ end Possible_Bit_Aligned_Component;
+
-------------------------
-- Remove_Side_Effects --
-------------------------
Name_Req : Boolean := False;
Variable_Ref : Boolean := False)
is
- Loc : constant Source_Ptr := Sloc (Exp);
+ Loc : constant Source_Ptr := Sloc (Exp);
Exp_Type : constant Entity_Id := Etype (Exp);
Svg_Suppress : constant Suppress_Array := Scope_Suppress;
Def_Id : Entity_Id;
E : Node_Id;
function Side_Effect_Free (N : Node_Id) return Boolean;
- -- Determines if the tree N represents an expression that is known
- -- not to have side effects, and for which no processing is required.
+ -- Determines if the tree N represents an expression that is known not
+ -- to have side effects, and for which no processing is required.
function Side_Effect_Free (L : List_Id) return Boolean;
-- Determines if all elements of the list L are side effect free
function Safe_Prefixed_Reference (N : Node_Id) return Boolean;
- -- The argument N is a construct where the Prefix is dereferenced
- -- if it is a an access type and the result is a variable. The call
- -- returns True if the construct is side effect free (not considering
- -- side effects in other than the prefix which are to be tested by the
- -- caller).
+ -- The argument N is a construct where the Prefix is dereferenced if it
+ -- is an access type and the result is a variable. The call returns True
+ -- if the construct is side effect free (not considering side effects in
+ -- other than the prefix which are to be tested by the caller).
function Within_In_Parameter (N : Node_Id) return Boolean;
- -- Determines if N is a subcomponent of a composite in-parameter.
- -- If so, N is not side-effect free when the actual is global and
- -- modifiable indirectly from within a subprogram, because it may
- -- be passed by reference. The front-end must be conservative here
- -- and assume that this may happen with any array or record type.
- -- On the other hand, we cannot create temporaries for all expressions
- -- for which this condition is true, for various reasons that might
- -- require clearing up ??? For example, descriminant references that
- -- appear out of place, or spurious type errors with class-wide
- -- expressions. As a result, we limit the transformation to loop
- -- bounds, which is so far the only case that requires it.
+ -- Determines if N is a subcomponent of a composite in-parameter. If so,
+ -- N is not side-effect free when the actual is global and modifiable
+ -- indirectly from within a subprogram, because it may be passed by
+ -- reference. The front-end must be conservative here and assume that
+ -- this may happen with any array or record type. On the other hand, we
+ -- cannot create temporaries for all expressions for which this
+ -- condition is true, for various reasons that might require clearing up
+ -- ??? For example, descriminant references that appear out of place, or
+ -- spurious type errors with class-wide expressions. As a result, we
+ -- limit the transformation to loop bounds, which is so far the only
+ -- case that requires it.
-----------------------------
-- Safe_Prefixed_Reference --
elsif Compile_Time_Known_Value (N) then
return True;
+
+ -- A variable renaming is not side-effet free, because the
+ -- renaming will function like a macro in the front-end in
+ -- some cases, and an assignment can modify the the component
+ -- designated by N, so we need to create a temporary for it.
+
+ elsif Is_Entity_Name (Original_Node (N))
+ and then Is_Renaming_Of_Object (Entity (Original_Node (N)))
+ and then Ekind (Entity (Original_Node (N))) /= E_Constant
+ then
+ return False;
end if;
-- For other than entity names and compile time known values,
when N_Attribute_Reference =>
return Side_Effect_Free (Expressions (N))
+ and then Attribute_Name (N) /= Name_Input
and then (Is_Entity_Name (Prefix (N))
or else Side_Effect_Free (Prefix (N)));
-- are side effect free. For this purpose binary operators
-- include membership tests and short circuit forms
- when N_Binary_Op |
- N_In |
- N_Not_In |
- N_And_Then |
- N_Or_Else =>
+ when N_Binary_Op |
+ N_Membership_Test |
+ N_And_Then |
+ N_Or_Else =>
return Side_Effect_Free (Left_Opnd (N))
and then Side_Effect_Free (Right_Opnd (N));
-- is a view conversion to a smaller object, where gigi can end up
-- creating its own temporary of the wrong size.
- -- ??? this transformation is inhibited for elementary types that are
- -- not involved in a change of representation because it causes
- -- regressions that are not fully understood yet.
-
- elsif Nkind (Exp) = N_Type_Conversion
- and then (not Is_Elementary_Type (Underlying_Type (Exp_Type))
- or else Nkind (Parent (Exp)) = N_Assignment_Statement)
- then
+ elsif Nkind (Exp) = N_Type_Conversion then
Remove_Side_Effects (Expression (Exp), Name_Req, Variable_Ref);
Scope_Suppress := Svg_Suppress;
return;
elsif Nkind (Exp) = N_Unchecked_Type_Conversion
and then not Safe_Unchecked_Type_Conversion (Exp)
then
- if Controlled_Type (Etype (Exp)) then
+ if CW_Or_Controlled_Type (Exp_Type) then
-- Use a renaming to capture the expression, rather than create
-- a controlled temporary.
if Nkind (Exp) = N_Selected_Component
and then Nkind (Prefix (Exp)) = N_Function_Call
- and then Is_Array_Type (Etype (Exp))
+ and then Is_Array_Type (Exp_Type)
then
-- Avoid generating a variable-sized temporary, by generating
-- the renaming declaration just for the function call. The
end if;
- -- The temporary must be elaborated by gigi, and is of course
- -- not to be replaced in-line by the expression it renames,
- -- which would defeat the purpose of removing the side-effect.
-
- Set_Is_Renaming_Of_Object (Def_Id, False);
+ -- If this is a packed reference, or a selected component with a
+ -- non-standard representation, a reference to the temporary will
+ -- be replaced by a copy of the original expression (see
+ -- exp_ch2.Expand_Renaming). Otherwise the temporary must be
+ -- elaborated by gigi, and is of course not to be replaced in-line
+ -- by the expression it renames, which would defeat the purpose of
+ -- removing the side-effect.
+
+ if (Nkind (Exp) = N_Selected_Component
+ or else Nkind (Exp) = N_Indexed_Component)
+ and then Has_Non_Standard_Rep (Etype (Prefix (Exp)))
+ then
+ null;
+ else
+ Set_Is_Renaming_Of_Object (Def_Id, False);
+ end if;
-- Otherwise we generate a reference to the value
else
return False;
end if;
-
end Safe_Unchecked_Type_Conversion;
+ ---------------------------------
+ -- Set_Current_Value_Condition --
+ ---------------------------------
+
+ -- Note: the implementation of this procedure is very closely tied to the
+ -- implementation of Get_Current_Value_Condition. Here we set required
+ -- Current_Value fields, and in Get_Current_Value_Condition, we interpret
+ -- them, so they must have a consistent view.
+
+ procedure Set_Current_Value_Condition (Cnode : Node_Id) is
+
+ procedure Set_Entity_Current_Value (N : Node_Id);
+ -- If N is an entity reference, where the entity is of an appropriate
+ -- kind, then set the current value of this entity to Cnode, unless
+ -- there is already a definite value set there.
+
+ procedure Set_Expression_Current_Value (N : Node_Id);
+ -- If N is of an appropriate form, sets an appropriate entry in current
+ -- value fields of relevant entities. Multiple entities can be affected
+ -- in the case of an AND or AND THEN.
+
+ ------------------------------
+ -- Set_Entity_Current_Value --
+ ------------------------------
+
+ procedure Set_Entity_Current_Value (N : Node_Id) is
+ begin
+ if Is_Entity_Name (N) then
+ declare
+ Ent : constant Entity_Id := Entity (N);
+
+ begin
+ -- Don't capture if not safe to do so
+
+ if not Safe_To_Capture_Value (N, Ent, Cond => True) then
+ return;
+ end if;
+
+ -- Here we have a case where the Current_Value field may
+ -- need to be set. We set it if it is not already set to a
+ -- compile time expression value.
+
+ -- Note that this represents a decision that one condition
+ -- blots out another previous one. That's certainly right
+ -- if they occur at the same level. If the second one is
+ -- nested, then the decision is neither right nor wrong (it
+ -- would be equally OK to leave the outer one in place, or
+ -- take the new inner one. Really we should record both, but
+ -- our data structures are not that elaborate.
+
+ if Nkind (Current_Value (Ent)) not in N_Subexpr then
+ Set_Current_Value (Ent, Cnode);
+ end if;
+ end;
+ end if;
+ end Set_Entity_Current_Value;
+
+ ----------------------------------
+ -- Set_Expression_Current_Value --
+ ----------------------------------
+
+ procedure Set_Expression_Current_Value (N : Node_Id) is
+ Cond : Node_Id;
+
+ begin
+ Cond := N;
+
+ -- Loop to deal with (ignore for now) any NOT operators present. The
+ -- presence of NOT operators will be handled properly when we call
+ -- Get_Current_Value_Condition.
+
+ while Nkind (Cond) = N_Op_Not loop
+ Cond := Right_Opnd (Cond);
+ end loop;
+
+ -- For an AND or AND THEN, recursively process operands
+
+ if Nkind (Cond) = N_Op_And or else Nkind (Cond) = N_And_Then then
+ Set_Expression_Current_Value (Left_Opnd (Cond));
+ Set_Expression_Current_Value (Right_Opnd (Cond));
+ return;
+ end if;
+
+ -- Check possible relational operator
+
+ if Nkind (Cond) in N_Op_Compare then
+ if Compile_Time_Known_Value (Right_Opnd (Cond)) then
+ Set_Entity_Current_Value (Left_Opnd (Cond));
+ elsif Compile_Time_Known_Value (Left_Opnd (Cond)) then
+ Set_Entity_Current_Value (Right_Opnd (Cond));
+ end if;
+
+ -- Check possible boolean variable reference
+
+ else
+ Set_Entity_Current_Value (Cond);
+ end if;
+ end Set_Expression_Current_Value;
+
+ -- Start of processing for Set_Current_Value_Condition
+
+ begin
+ Set_Expression_Current_Value (Condition (Cnode));
+ end Set_Current_Value_Condition;
+
--------------------------
-- Set_Elaboration_Flag --
--------------------------
end if;
end Set_Elaboration_Flag;
+ ----------------------------
+ -- Set_Renamed_Subprogram --
+ ----------------------------
+
+ procedure Set_Renamed_Subprogram (N : Node_Id; E : Entity_Id) is
+ begin
+ -- If input node is an identifier, we can just reset it
+
+ if Nkind (N) = N_Identifier then
+ Set_Chars (N, Chars (E));
+ Set_Entity (N, E);
+
+ -- Otherwise we have to do a rewrite, preserving Comes_From_Source
+
+ else
+ declare
+ CS : constant Boolean := Comes_From_Source (N);
+ begin
+ Rewrite (N, Make_Identifier (Sloc (N), Chars => Chars (E)));
+ Set_Entity (N, E);
+ Set_Comes_From_Source (N, CS);
+ Set_Analyzed (N, True);
+ end;
+ end if;
+ end Set_Renamed_Subprogram;
+
--------------------------
-- Target_Has_Fixed_Ops --
--------------------------
E : Entity_Id;
begin
- E := First_Entity (Typ);
+ E := First_Component_Or_Discriminant (Typ);
while Present (E) loop
- if Ekind (E) = E_Component
- or else Ekind (E) = E_Discriminant
+ if Component_May_Be_Bit_Aligned (E)
+ or else Type_May_Have_Bit_Aligned_Components (Etype (E))
then
- if Component_May_Be_Bit_Aligned (E)
- or else
- Type_May_Have_Bit_Aligned_Components (Etype (E))
- then
- return True;
- end if;
+ return True;
end if;
- Next_Entity (E);
+ Next_Component_Or_Discriminant (E);
end loop;
return False;
OSDN Git Service
