with Einfo; use Einfo;
with Errout; use Errout;
with Elists; use Elists;
+with Exp_Aggr; use Exp_Aggr;
with Exp_Atag; use Exp_Atag;
with Exp_Ch2; use Exp_Ch2;
with Exp_Ch3; use Exp_Ch3;
-- along directly to the build-in-place function. Finally, if Return_Object
-- is empty, then pass a null literal as the actual.
- procedure Add_Alloc_Form_Actual_To_Build_In_Place_Call
+ procedure Add_Unconstrained_Actuals_To_Build_In_Place_Call
(Function_Call : Node_Id;
Function_Id : Entity_Id;
Alloc_Form : BIP_Allocation_Form := Unspecified;
- Alloc_Form_Exp : Node_Id := Empty);
- -- Ada 2005 (AI-318-02): Add an actual indicating the form of allocation,
- -- if any, to be done by a build-in-place function. If Alloc_Form_Exp is
- -- present, then use it, otherwise pass a literal corresponding to the
- -- Alloc_Form parameter (which must not be Unspecified in that case).
-
- procedure Add_Extra_Actual_To_Call
- (Subprogram_Call : Node_Id;
- Extra_Formal : Entity_Id;
- Extra_Actual : Node_Id);
- -- Adds Extra_Actual as a named parameter association for the formal
- -- Extra_Formal in Subprogram_Call.
+ Alloc_Form_Exp : Node_Id := Empty;
+ Pool_Actual : Node_Id := Make_Null (No_Location));
+ -- Ada 2005 (AI-318-02): Add the actuals needed for a build-in-place
+ -- function call that returns a caller-unknown-size result (BIP_Alloc_Form
+ -- and BIP_Storage_Pool). If Alloc_Form_Exp is present, then use it,
+ -- otherwise pass a literal corresponding to the Alloc_Form parameter
+ -- (which must not be Unspecified in that case). Pool_Actual is the
+ -- parameter to pass to BIP_Storage_Pool.
procedure Add_Finalization_Master_Actual_To_Build_In_Place_Call
- (Func_Call : Node_Id;
- Func_Id : Entity_Id;
- Ptr_Typ : Entity_Id := Empty);
+ (Func_Call : Node_Id;
+ Func_Id : Entity_Id;
+ Ptr_Typ : Entity_Id := Empty;
+ Master_Exp : Node_Id := Empty);
-- Ada 2005 (AI-318-02): If the result type of a build-in-place call needs
-- finalization actions, add an actual parameter which is a pointer to the
- -- finalization master of the caller. If Ptr_Typ is left Empty, this will
- -- result in an automatic "null" value for the actual.
+ -- finalization master of the caller. If Master_Exp is not Empty, then that
+ -- will be passed as the actual. Otherwise, if Ptr_Typ is left Empty, this
+ -- will result in an automatic "null" value for the actual.
procedure Add_Task_Actuals_To_Build_In_Place_Call
(Function_Call : Node_Id;
-- the values are not changed for the call, we know immediately that
-- we have an infinite recursion.
- procedure Expand_Actuals (N : Node_Id; Subp : Entity_Id);
- -- For each actual of an in-out or out parameter which is a numeric
- -- (view) conversion of the form T (A), where A denotes a variable,
- -- we insert the declaration:
- --
- -- Temp : T[ := T (A)];
- --
- -- prior to the call. Then we replace the actual with a reference to Temp,
- -- and append the assignment:
- --
- -- A := TypeA (Temp);
- --
- -- after the call. Here TypeA is the actual type of variable A. For out
- -- parameters, the initial declaration has no expression. If A is not an
- -- entity name, we generate instead:
- --
- -- Var : TypeA renames A;
- -- Temp : T := Var; -- omitting expression for out parameter.
- -- ...
- -- Var := TypeA (Temp);
- --
- -- For other in-out parameters, we emit the required constraint checks
- -- before and/or after the call.
- --
- -- For all parameter modes, actuals that denote components and slices of
- -- packed arrays are expanded into suitable temporaries.
- --
- -- For non-scalar objects that are possibly unaligned, add call by copy
- -- code (copy in for IN and IN OUT, copy out for OUT and IN OUT).
-
procedure Expand_Ctrl_Function_Call (N : Node_Id);
-- N is a function call which returns a controlled object. Transform the
-- call into a temporary which retrieves the returned object from the
procedure Expand_Non_Function_Return (N : Node_Id);
-- Called by Expand_N_Simple_Return_Statement in case we're returning from
-- a procedure body, entry body, accept statement, or extended return
- -- statement. Note that all non-function returns are simple return
+ -- statement. Note that all non-function returns are simple return
-- statements.
function Expand_Protected_Object_Reference
-- reference to the object itself, and the call becomes a call to the
-- corresponding protected subprogram.
+ function Has_Unconstrained_Access_Discriminants
+ (Subtyp : Entity_Id) return Boolean;
+ -- Returns True if the given subtype is unconstrained and has one
+ -- or more access discriminants.
+
procedure Expand_Simple_Function_Return (N : Node_Id);
-- Expand simple return from function. In the case where we are returning
-- from a function body this is called by Expand_N_Simple_Return_Statement.
Add_Extra_Actual_To_Call (Function_Call, Obj_Acc_Formal, Obj_Address);
end Add_Access_Actual_To_Build_In_Place_Call;
- --------------------------------------------------
- -- Add_Alloc_Form_Actual_To_Build_In_Place_Call --
- --------------------------------------------------
+ ------------------------------------------------------
+ -- Add_Unconstrained_Actuals_To_Build_In_Place_Call --
+ ------------------------------------------------------
- procedure Add_Alloc_Form_Actual_To_Build_In_Place_Call
+ procedure Add_Unconstrained_Actuals_To_Build_In_Place_Call
(Function_Call : Node_Id;
Function_Id : Entity_Id;
Alloc_Form : BIP_Allocation_Form := Unspecified;
- Alloc_Form_Exp : Node_Id := Empty)
+ Alloc_Form_Exp : Node_Id := Empty;
+ Pool_Actual : Node_Id := Make_Null (No_Location))
is
Loc : constant Source_Ptr := Sloc (Function_Call);
Alloc_Form_Actual : Node_Id;
Alloc_Form_Formal : Node_Id;
+ Pool_Formal : Node_Id;
begin
-- The allocation form generally doesn't need to be passed in the case
Add_Extra_Actual_To_Call
(Function_Call, Alloc_Form_Formal, Alloc_Form_Actual);
- end Add_Alloc_Form_Actual_To_Build_In_Place_Call;
+
+ -- Pass the Storage_Pool parameter. This parameter is omitted on
+ -- .NET/JVM/ZFP as those targets do not support pools.
+
+ if VM_Target = No_VM
+ and then RTE_Available (RE_Root_Storage_Pool_Ptr)
+ then
+ Pool_Formal := Build_In_Place_Formal (Function_Id, BIP_Storage_Pool);
+ Analyze_And_Resolve (Pool_Actual, Etype (Pool_Formal));
+ Add_Extra_Actual_To_Call
+ (Function_Call, Pool_Formal, Pool_Actual);
+ end if;
+ end Add_Unconstrained_Actuals_To_Build_In_Place_Call;
-----------------------------------------------------------
-- Add_Finalization_Master_Actual_To_Build_In_Place_Call --
-----------------------------------------------------------
procedure Add_Finalization_Master_Actual_To_Build_In_Place_Call
- (Func_Call : Node_Id;
- Func_Id : Entity_Id;
- Ptr_Typ : Entity_Id := Empty)
+ (Func_Call : Node_Id;
+ Func_Id : Entity_Id;
+ Ptr_Typ : Entity_Id := Empty;
+ Master_Exp : Node_Id := Empty)
is
begin
if not Needs_BIP_Finalization_Master (Func_Id) then
Desig_Typ : Entity_Id;
begin
+ -- If there is a finalization master actual, such as the implicit
+ -- finalization master of an enclosing build-in-place function,
+ -- then this must be added as an extra actual of the call.
+
+ if Present (Master_Exp) then
+ Actual := Master_Exp;
+
-- Case where the context does not require an actual master
- if No (Ptr_Typ) then
+ elsif No (Ptr_Typ) then
Actual := Make_Null (Loc);
else
Function_Id : Entity_Id;
Master_Actual : Node_Id)
is
- Loc : constant Source_Ptr := Sloc (Function_Call);
- Actual : Node_Id := Master_Actual;
+ Loc : constant Source_Ptr := Sloc (Function_Call);
+ Result_Subt : constant Entity_Id :=
+ Available_View (Etype (Function_Id));
+ Actual : Node_Id;
+ Chain_Actual : Node_Id;
+ Chain_Formal : Node_Id;
+ Master_Formal : Node_Id;
begin
-- No such extra parameters are needed if there are no tasks
- if not Has_Task (Etype (Function_Id)) then
+ if not Has_Task (Result_Subt) then
return;
end if;
+ Actual := Master_Actual;
+
-- Use a dummy _master actual in case of No_Task_Hierarchy
if Restriction_Active (No_Task_Hierarchy) then
Actual := New_Occurrence_Of (RTE (RE_Library_Task_Level), Loc);
- end if;
-
- -- The master
- declare
- Master_Formal : Node_Id;
- begin
- -- Locate implicit master parameter in the called function
+ -- In the case where we use the master associated with an access type,
+ -- the actual is an entity and requires an explicit reference.
- Master_Formal := Build_In_Place_Formal (Function_Id, BIP_Master);
+ elsif Nkind (Actual) = N_Defining_Identifier then
+ Actual := New_Reference_To (Actual, Loc);
+ end if;
- Analyze_And_Resolve (Actual, Etype (Master_Formal));
+ -- Locate the implicit master parameter in the called function
- -- Build the parameter association for the new actual and add it to
- -- the end of the function's actuals.
+ Master_Formal := Build_In_Place_Formal (Function_Id, BIP_Task_Master);
+ Analyze_And_Resolve (Actual, Etype (Master_Formal));
- Add_Extra_Actual_To_Call
- (Function_Call, Master_Formal, Actual);
- end;
-
- -- The activation chain
+ -- Build the parameter association for the new actual and add it to the
+ -- end of the function's actuals.
- declare
- Activation_Chain_Actual : Node_Id;
- Activation_Chain_Formal : Node_Id;
+ Add_Extra_Actual_To_Call (Function_Call, Master_Formal, Actual);
- begin
- -- Locate implicit activation chain parameter in the called function
+ -- Locate the implicit activation chain parameter in the called function
- Activation_Chain_Formal := Build_In_Place_Formal
- (Function_Id, BIP_Activation_Chain);
+ Chain_Formal :=
+ Build_In_Place_Formal (Function_Id, BIP_Activation_Chain);
- -- Create the actual which is a pointer to the current activation
- -- chain
+ -- Create the actual which is a pointer to the current activation chain
- Activation_Chain_Actual :=
- Make_Attribute_Reference (Loc,
- Prefix => Make_Identifier (Loc, Name_uChain),
- Attribute_Name => Name_Unrestricted_Access);
+ Chain_Actual :=
+ Make_Attribute_Reference (Loc,
+ Prefix => Make_Identifier (Loc, Name_uChain),
+ Attribute_Name => Name_Unrestricted_Access);
- Analyze_And_Resolve
- (Activation_Chain_Actual, Etype (Activation_Chain_Formal));
+ Analyze_And_Resolve (Chain_Actual, Etype (Chain_Formal));
- -- Build the parameter association for the new actual and add it to
- -- the end of the function's actuals.
+ -- Build the parameter association for the new actual and add it to the
+ -- end of the function's actuals.
- Add_Extra_Actual_To_Call
- (Function_Call, Activation_Chain_Formal, Activation_Chain_Actual);
- end;
+ Add_Extra_Actual_To_Call (Function_Call, Chain_Formal, Chain_Actual);
end Add_Task_Actuals_To_Build_In_Place_Call;
-----------------------
case Kind is
when BIP_Alloc_Form =>
return "BIPalloc";
+ when BIP_Storage_Pool =>
+ return "BIPstoragepool";
when BIP_Finalization_Master =>
return "BIPfinalizationmaster";
- when BIP_Master =>
- return "BIPmaster";
+ when BIP_Task_Master =>
+ return "BIPtaskmaster";
when BIP_Activation_Chain =>
return "BIPactivationchain";
when BIP_Object_Access =>
(Func : Entity_Id;
Kind : BIP_Formal_Kind) return Entity_Id
is
+ Formal_Name : constant Name_Id :=
+ New_External_Name
+ (Chars (Func), BIP_Formal_Suffix (Kind));
Extra_Formal : Entity_Id := Extra_Formals (Func);
begin
-- Maybe it would be better for each implicit formal of a build-in-place
-- function to have a flag or a Uint attribute to identify it. ???
+ -- The return type in the function declaration may have been a limited
+ -- view, and the extra formals for the function were not generated at
+ -- that point. At the point of call the full view must be available and
+ -- the extra formals can be created.
+
+ if No (Extra_Formal) then
+ Create_Extra_Formals (Func);
+ Extra_Formal := Extra_Formals (Func);
+ end if;
+
loop
pragma Assert (Present (Extra_Formal));
- exit when
- Chars (Extra_Formal) =
- New_External_Name (Chars (Func), BIP_Formal_Suffix (Kind));
+ exit when Chars (Extra_Formal) = Formal_Name;
+
Next_Formal_With_Extras (Extra_Formal);
end loop;
Set_Assignment_OK (Lhs);
- Append_To (Post_Call,
- Make_Assignment_Statement (Loc,
- Name => Lhs,
- Expression => Expr));
+ if Is_Access_Type (E_Formal)
+ and then Is_Entity_Name (Lhs)
+ and then
+ Present (Effective_Extra_Accessibility (Entity (Lhs)))
+ then
+ -- Copyback target is an Ada 2012 stand-alone object
+ -- of an anonymous access type
+
+ pragma Assert (Ada_Version >= Ada_2012);
+
+ if Type_Access_Level (E_Formal) >
+ Object_Access_Level (Lhs)
+ then
+ Append_To (Post_Call,
+ Make_Raise_Program_Error (Loc,
+ Reason => PE_Accessibility_Check_Failed));
+ end if;
+
+ Append_To (Post_Call,
+ Make_Assignment_Statement (Loc,
+ Name => Lhs,
+ Expression => Expr));
+
+ -- We would like to somehow suppress generation of the
+ -- extra_accessibility assignment generated by the expansion
+ -- of the above assignment statement. It's not a correctness
+ -- issue because the following assignment renders it dead,
+ -- but generating back-to-back assignments to the same
+ -- target is undesirable. ???
+
+ Append_To (Post_Call,
+ Make_Assignment_Statement (Loc,
+ Name => New_Occurrence_Of (
+ Effective_Extra_Accessibility (Entity (Lhs)), Loc),
+ Expression => Make_Integer_Literal (Loc,
+ Type_Access_Level (E_Formal))));
+
+ else
+ Append_To (Post_Call,
+ Make_Assignment_Statement (Loc,
+ Name => Lhs,
+ Expression => Expr));
+ end if;
end;
end if;
end Add_Call_By_Copy_Code;
if not Is_Empty_List (Post_Call) then
- -- If call is not a list member, it must be the triggering statement
- -- of a triggering alternative or an entry call alternative, and we
- -- can add the post call stuff to the corresponding statement list.
+ -- Cases where the call is not a member of a statement list
if not Is_List_Member (N) then
declare
- P : constant Node_Id := Parent (N);
+ P : Node_Id := Parent (N);
begin
- pragma Assert (Nkind_In (P, N_Triggering_Alternative,
- N_Entry_Call_Alternative));
+ -- In Ada 2012 the call may be a function call in an expression
+ -- (since OUT and IN OUT parameters are now allowed for such
+ -- calls. The write-back of (in)-out parameters is handled
+ -- by the back-end, but the constraint checks generated when
+ -- subtypes of formal and actual don't match must be inserted
+ -- in the form of assignments, at the nearest point after the
+ -- declaration or statement that contains the call.
+
+ if Ada_Version >= Ada_2012
+ and then Nkind (N) = N_Function_Call
+ then
+ while Nkind (P) not in N_Declaration
+ and then
+ Nkind (P) not in N_Statement_Other_Than_Procedure_Call
+ loop
+ P := Parent (P);
+ end loop;
+
+ Insert_Actions_After (P, Post_Call);
+
+ -- If not the special Ada 2012 case of a function call, then
+ -- we must have the triggering statement of a triggering
+ -- alternative or an entry call alternative, and we can add
+ -- the post call stuff to the corresponding statement list.
- if Is_Non_Empty_List (Statements (P)) then
- Insert_List_Before_And_Analyze
- (First (Statements (P)), Post_Call);
else
- Set_Statements (P, Post_Call);
+ pragma Assert (Nkind_In (P, N_Triggering_Alternative,
+ N_Entry_Call_Alternative));
+
+ if Is_Non_Empty_List (Statements (P)) then
+ Insert_List_Before_And_Analyze
+ (First (Statements (P)), Post_Call);
+ else
+ Set_Statements (P, Post_Call);
+ end if;
end if;
+
end;
-- Otherwise, normal case where N is in a statement sequence,
if No (Prev) then
if No (Parameter_Associations (Call_Node)) then
Set_Parameter_Associations (Call_Node, New_List);
- Append (Insert_Param, Parameter_Associations (Call_Node));
end if;
+
+ Append (Insert_Param, Parameter_Associations (Call_Node));
+
else
Insert_After (Prev, Insert_Param);
end if;
-- as we go through the loop, since this is a convenient place to do it.
-- (Though it seems that this would be better done in Expand_Actuals???)
- Formal := First_Formal (Subp);
- Actual := First_Actual (Call_Node);
+ Formal := First_Formal (Subp);
+ Actual := First_Actual (Call_Node);
Param_Count := 1;
while Present (Formal) loop
CW_Interface_Formals_Present
or else
(Ekind (Etype (Formal)) = E_Class_Wide_Type
- and then Is_Interface (Etype (Etype (Formal))))
+ and then Is_Interface (Etype (Etype (Formal))))
or else
(Ekind (Etype (Formal)) = E_Anonymous_Access_Type
and then Is_Interface (Directly_Designated_Type
else
Add_Extra_Actual
- (Make_Integer_Literal (Loc,
- Intval => Type_Access_Level (Etype (Prev_Orig))),
+ (Dynamic_Accessibility_Level (Prev_Orig),
Extra_Accessibility (Formal));
end if;
-- For X'Access, pass on the level of the prefix X
when Attribute_Access =>
- Add_Extra_Actual
- (Make_Integer_Literal (Loc,
- Intval =>
- Object_Access_Level
- (Prefix (Prev_Orig))),
- Extra_Accessibility (Formal));
+
+ -- If this is an Access attribute applied to the
+ -- the current instance object passed to a type
+ -- initialization procedure, then use the level
+ -- of the type itself. This is not really correct,
+ -- as there should be an extra level parameter
+ -- passed in with _init formals (only in the case
+ -- where the type is immutably limited), but we
+ -- don't have an easy way currently to create such
+ -- an extra formal (init procs aren't ever frozen).
+ -- For now we just use the level of the type,
+ -- which may be too shallow, but that works better
+ -- than passing Object_Access_Level of the type,
+ -- which can be one level too deep in some cases.
+ -- ???
+
+ if Is_Entity_Name (Prefix (Prev_Orig))
+ and then Is_Type (Entity (Prefix (Prev_Orig)))
+ then
+ Add_Extra_Actual
+ (Make_Integer_Literal (Loc,
+ Intval =>
+ Type_Access_Level
+ (Entity (Prefix (Prev_Orig)))),
+ Extra_Accessibility (Formal));
+
+ else
+ Add_Extra_Actual
+ (Make_Integer_Literal (Loc,
+ Intval =>
+ Object_Access_Level
+ (Prefix (Prev_Orig))),
+ Extra_Accessibility (Formal));
+ end if;
-- Treat the unchecked attributes as library-level
Intval => Scope_Depth (Current_Scope) + 1),
Extra_Accessibility (Formal));
- -- For other cases we simply pass the level of the actual's
- -- access type. The type is retrieved from Prev rather than
- -- Prev_Orig, because in some cases Prev_Orig denotes an
- -- original expression that has not been analyzed.
+ -- For most other cases we simply pass the level of the
+ -- actual's access type. The type is retrieved from
+ -- Prev rather than Prev_Orig, because in some cases
+ -- Prev_Orig denotes an original expression that has
+ -- not been analyzed.
when others =>
Add_Extra_Actual
- (Make_Integer_Literal (Loc,
- Intval => Type_Access_Level (Etype (Prev))),
+ (Dynamic_Accessibility_Level (Prev),
Extra_Accessibility (Formal));
end case;
end if;
and then Ekind (Formal) /= E_Out_Parameter
and then Nkind (Prev) /= N_Raise_Constraint_Error
and then (Known_Null (Prev)
- or else not Can_Never_Be_Null (Etype (Prev)))
+ or else not Can_Never_Be_Null (Etype (Prev)))
then
Install_Null_Excluding_Check (Prev);
end if;
if Validity_Checks_On then
if (Ekind (Formal) = E_In_Parameter
- and then Validity_Check_In_Params)
+ and then Validity_Check_In_Params)
or else
(Ekind (Formal) = E_In_Out_Parameter
- and then Validity_Check_In_Out_Params)
+ and then Validity_Check_In_Out_Params)
then
-- If the actual is an indexed component of a packed type (or
-- is an indexed or selected component whose prefix recursively
end if;
end if;
+ -- For Ada 2012, if a parameter is aliased, the actual must be a
+ -- tagged type or an aliased view of an object.
+
+ if Is_Aliased (Formal)
+ and then not Is_Aliased_View (Actual)
+ and then not Is_Tagged_Type (Etype (Formal))
+ then
+ Error_Msg_NE
+ ("actual for aliased formal& must be aliased object",
+ Actual, Formal);
+ end if;
+
-- For IN OUT and OUT parameters, ensure that subscripts are valid
-- since this is a left side reference. We only do this for calls
-- from the source program since we assume that compiler generated
-- or IN OUT parameter! We do reset the Is_Known_Valid flag
-- since the subprogram could have returned in invalid value.
- if (Ekind (Formal) = E_Out_Parameter
- or else
- Ekind (Formal) = E_In_Out_Parameter)
+ if Ekind_In (Formal, E_Out_Parameter, E_In_Out_Parameter)
and then Is_Assignable (Ent)
then
Sav := Last_Assignment (Ent);
Next_Formal (Formal);
end loop;
+ -- If we are calling an Ada 2012 function which needs to have the
+ -- "accessibility level determined by the point of call" (AI05-0234)
+ -- passed in to it, then pass it in.
+
+ if Ekind_In (Subp, E_Function, E_Operator, E_Subprogram_Type)
+ and then
+ Present (Extra_Accessibility_Of_Result (Ultimate_Alias (Subp)))
+ then
+ declare
+ Ancestor : Node_Id := Parent (Call_Node);
+ Level : Node_Id := Empty;
+ Defer : Boolean := False;
+
+ begin
+ -- Unimplemented: if Subp returns an anonymous access type, then
+
+ -- a) if the call is the operand of an explict conversion, then
+ -- the target type of the conversion (a named access type)
+ -- determines the accessibility level pass in;
+
+ -- b) if the call defines an access discriminant of an object
+ -- (e.g., the discriminant of an object being created by an
+ -- allocator, or the discriminant of a function result),
+ -- then the accessibility level to pass in is that of the
+ -- discriminated object being initialized).
+
+ -- ???
+
+ while Nkind (Ancestor) = N_Qualified_Expression
+ loop
+ Ancestor := Parent (Ancestor);
+ end loop;
+
+ case Nkind (Ancestor) is
+ when N_Allocator =>
+
+ -- At this point, we'd like to assign
+
+ -- Level := Dynamic_Accessibility_Level (Ancestor);
+
+ -- but Etype of Ancestor may not have been set yet,
+ -- so that doesn't work.
+
+ -- Handle this later in Expand_Allocator_Expression.
+
+ Defer := True;
+
+ when N_Object_Declaration | N_Object_Renaming_Declaration =>
+ declare
+ Def_Id : constant Entity_Id :=
+ Defining_Identifier (Ancestor);
+
+ begin
+ if Is_Return_Object (Def_Id) then
+ if Present (Extra_Accessibility_Of_Result
+ (Return_Applies_To (Scope (Def_Id))))
+ then
+ -- Pass along value that was passed in if the
+ -- routine we are returning from also has an
+ -- Accessibility_Of_Result formal.
+
+ Level :=
+ New_Occurrence_Of
+ (Extra_Accessibility_Of_Result
+ (Return_Applies_To (Scope (Def_Id))), Loc);
+ end if;
+ else
+ Level :=
+ Make_Integer_Literal (Loc,
+ Intval => Object_Access_Level (Def_Id));
+ end if;
+ end;
+
+ when N_Simple_Return_Statement =>
+ if Present (Extra_Accessibility_Of_Result
+ (Return_Applies_To
+ (Return_Statement_Entity (Ancestor))))
+ then
+ -- Pass along value that was passed in if the routine
+ -- we are returning from also has an
+ -- Accessibility_Of_Result formal.
+
+ Level :=
+ New_Occurrence_Of
+ (Extra_Accessibility_Of_Result
+ (Return_Applies_To
+ (Return_Statement_Entity (Ancestor))), Loc);
+ end if;
+
+ when others =>
+ null;
+ end case;
+
+ if not Defer then
+ if not Present (Level) then
+
+ -- The "innermost master that evaluates the function call".
+
+ -- ??? - Should we use Integer'Last here instead in order
+ -- to deal with (some of) the problems associated with
+ -- calls to subps whose enclosing scope is unknown (e.g.,
+ -- Anon_Access_To_Subp_Param.all)?
+
+ Level := Make_Integer_Literal (Loc,
+ Scope_Depth (Current_Scope) + 1);
+ end if;
+
+ Add_Extra_Actual
+ (Level,
+ Extra_Accessibility_Of_Result (Ultimate_Alias (Subp)));
+ end if;
+ end;
+ end if;
+
-- If we are expanding a rhs of an assignment we need to check if tag
-- propagation is needed. You might expect this processing to be in
-- Analyze_Assignment but has to be done earlier (bottom-up) because the
New_A : Node_Id;
Num_Ret : Int := 0;
Ret_Type : Entity_Id;
- Targ : Node_Id;
- Targ1 : Node_Id;
+
+ Targ : Node_Id;
+ -- The target of the call. If context is an assignment statement then
+ -- this is the left-hand side of the assignment. else it is a temporary
+ -- to which the return value is assigned prior to rewriting the call.
+
+ Targ1 : Node_Id;
+ -- A separate target used when the return type is unconstrained
+
Temp : Entity_Id;
Temp_Typ : Entity_Id;
-- Entity in declaration in an extended_return_statement
Is_Unc : constant Boolean :=
- Is_Array_Type (Etype (Subp))
- and then not Is_Constrained (Etype (Subp));
+ Is_Array_Type (Etype (Subp))
+ and then not Is_Constrained (Etype (Subp));
-- If the type returned by the function is unconstrained and the call
-- can be inlined, special processing is required.
Rewrite (N, New_Copy (A));
end if;
end if;
+
return Skip;
elsif Is_Entity_Name (N)
if Nkind_In (Expression (N), N_Aggregate, N_Null) then
Ret :=
Make_Qualified_Expression (Sloc (N),
- Subtype_Mark => New_Occurrence_Of (Ret_Type, Sloc (N)),
- Expression => Relocate_Node (Expression (N)));
+ Subtype_Mark => New_Occurrence_Of (Ret_Type, Sloc (N)),
+ Expression => Relocate_Node (Expression (N)));
else
Ret :=
Unchecked_Convert_To
if Nkind (Targ) = N_Defining_Identifier then
Rewrite (N,
Make_Assignment_Statement (Loc,
- Name => New_Occurrence_Of (Targ, Loc),
+ Name => New_Occurrence_Of (Targ, Loc),
Expression => Ret));
else
Rewrite (N,
Make_Assignment_Statement (Loc,
- Name => New_Copy (Targ),
+ Name => New_Copy (Targ),
Expression => Ret));
end if;
if Present (Exit_Lab) then
Insert_After (N,
- Make_Goto_Statement (Loc,
- Name => New_Copy (Lab_Id)));
+ Make_Goto_Statement (Loc, Name => New_Copy (Lab_Id)));
end if;
end if;
return OK;
- elsif Nkind (N) = N_Extended_Return_Statement then
-
- -- An extended return becomes a block whose first statement is
- -- the assignment of the initial expression of the return object
- -- to the target of the call itself.
+ -- An extended return becomes a block whose first statement is the
+ -- assignment of the initial expression of the return object to the
+ -- target of the call itself.
+ elsif Nkind (N) = N_Extended_Return_Statement then
declare
Return_Decl : constant Entity_Id :=
First (Return_Object_Declarations (N));
if Nkind (Targ) = N_Defining_Identifier then
Assign :=
Make_Assignment_Statement (Loc,
- Name => New_Occurrence_Of (Targ, Loc),
+ Name => New_Occurrence_Of (Targ, Loc),
Expression => Expression (Return_Decl));
else
Assign :=
Make_Assignment_Statement (Loc,
- Name => New_Copy (Targ),
+ Name => New_Copy (Targ),
Expression => Expression (Return_Decl));
end if;
and then Nkind (Fst) = N_Assignment_Statement
and then No (Next (Fst))
then
-
-- The function call may have been rewritten as the temporary
-- that holds the result of the call, in which case remove the
-- now useless declaration.
Insert_After (Parent (Entity (N)), Blk);
+ -- If the context is an assignment, and the left-hand side is free of
+ -- side-effects, the replacement is also safe.
+ -- Can this be generalized further???
+
elsif Nkind (Parent (N)) = N_Assignment_Statement
and then
(Is_Entity_Name (Name (Parent (N)))
- or else
- (Nkind (Name (Parent (N))) = N_Explicit_Dereference
- and then Is_Entity_Name (Prefix (Name (Parent (N))))))
+ or else
+ (Nkind (Name (Parent (N))) = N_Explicit_Dereference
+ and then Is_Entity_Name (Prefix (Name (Parent (N)))))
+
+ or else
+ (Nkind (Name (Parent (N))) = N_Selected_Component
+ and then Is_Entity_Name (Prefix (Name (Parent (N))))))
then
-- Replace assignment with the block
procedure Rewrite_Procedure_Call (N : Node_Id; Blk : Node_Id) is
HSS : constant Node_Id := Handled_Statement_Sequence (Blk);
+
begin
-- If there is a transient scope for N, this will be the scope of the
-- actions for N, and the statements in Blk need to be within this
-- Start of processing for Expand_Inlined_Call
begin
-
-- Check for an illegal attempt to inline a recursive procedure. If the
-- subprogram has parameters this is detected when trying to supply a
-- binding for parameters that already have one. For parameterless
Set_Declarations (Blk, New_List);
end if;
- -- For the unconstrained case, capture the name of the local
- -- variable that holds the result. This must be the first declaration
- -- in the block, because its bounds cannot depend on local variables.
- -- Otherwise there is no way to declare the result outside of the
- -- block. Needless to say, in general the bounds will depend on the
- -- actuals in the call.
+ -- For the unconstrained case, capture the name of the local variable
+ -- that holds the result. This must be the first declaration in the
+ -- block, because its bounds cannot depend on local variables. Otherwise
+ -- there is no way to declare the result outside of the block. Needless
+ -- to say, in general the bounds will depend on the actuals in the call.
+
+ -- If the context is an assignment statement, as is the case for the
+ -- expansion of an extended return, the left-hand side provides bounds
+ -- even if the return type is unconstrained.
if Is_Unc then
- Targ1 := Defining_Identifier (First (Declarations (Blk)));
+ if Nkind (Parent (N)) /= N_Assignment_Statement then
+ Targ1 := Defining_Identifier (First (Declarations (Blk)));
+ else
+ Targ1 := Name (Parent (N));
+ end if;
end if;
-- If this is a derived function, establish the proper return type
- if Present (Orig_Subp)
- and then Orig_Subp /= Subp
- then
+ if Present (Orig_Subp) and then Orig_Subp /= Subp then
Ret_Type := Etype (Orig_Subp);
else
Ret_Type := Etype (Subp);
if Is_Class_Wide_Type (Etype (F))
or else (Is_Access_Type (Etype (F))
- and then
- Is_Class_Wide_Type (Designated_Type (Etype (F))))
+ and then Is_Class_Wide_Type (Designated_Type (Etype (F))))
then
Temp_Typ := Etype (F);
and then Etype (F) /= Base_Type (Etype (F))
then
Temp_Typ := Etype (F);
-
else
Temp_Typ := Etype (A);
end if;
or else
(Nkind_In (A, N_Real_Literal,
- N_Integer_Literal,
- N_Character_Literal)
- and then not Address_Taken (F))
+ N_Integer_Literal,
+ N_Character_Literal)
+ and then not Address_Taken (F))
then
if Etype (F) /= Etype (A) then
Set_Renamed_Object
- (F, Unchecked_Convert_To (Etype (F), Relocate_Node (A)));
+ (F, Unchecked_Convert_To (Etype (F), Relocate_Node (A)));
else
Set_Renamed_Object (F, A);
end if;
-- code will have the same semantics.
if Ekind (F) = E_In_Parameter
- and then not Is_Limited_Type (Etype (A))
- and then not Is_Tagged_Type (Etype (A))
+ and then not Is_By_Reference_Type (Etype (A))
and then
- (not Is_Array_Type (Etype (A))
- or else not Is_Object_Reference (A)
- or else Is_Bit_Packed_Array (Etype (A)))
+ (not Is_Array_Type (Etype (A))
+ or else not Is_Object_Reference (A)
+ or else Is_Bit_Packed_Array (Etype (A)))
then
Decl :=
Make_Object_Declaration (Loc,
Defining_Identifier => Temp,
- Constant_Present => True,
- Object_Definition => New_Occurrence_Of (Temp_Typ, Loc),
- Expression => New_A);
+ Constant_Present => True,
+ Object_Definition => New_Occurrence_Of (Temp_Typ, Loc),
+ Expression => New_A);
else
Decl :=
Make_Object_Renaming_Declaration (Loc,
end loop;
-- Establish target of function call. If context is not assignment or
- -- declaration, create a temporary as a target. The declaration for
- -- the temporary may be subsequently optimized away if the body is a
- -- single expression, or if the left-hand side of the assignment is
- -- simple enough, i.e. an entity or an explicit dereference of one.
+ -- declaration, create a temporary as a target. The declaration for the
+ -- temporary may be subsequently optimized away if the body is a single
+ -- expression, or if the left-hand side of the assignment is simple
+ -- enough, i.e. an entity or an explicit dereference of one.
if Ekind (Subp) = E_Function then
if Nkind (Parent (N)) = N_Assignment_Statement
then
Targ := Name (Parent (N));
+ elsif Nkind (Parent (N)) = N_Assignment_Statement
+ and then Nkind (Name (Parent (N))) = N_Selected_Component
+ and then Is_Entity_Name (Prefix (Name (Parent (N))))
+ then
+ Targ := New_Copy_Tree (Name (Parent (N)));
+
elsif Nkind (Parent (N)) = N_Object_Declaration
and then Is_Limited_Type (Etype (Subp))
then
-- eventually be possible to remove that temporary and use the
-- result variable directly.
- if Is_Unc then
+ if Is_Unc
+ and then Nkind (Parent (N)) /= N_Assignment_Statement
+ then
Decl :=
Make_Object_Declaration (Loc,
Defining_Identifier => Temp,
- Object_Definition =>
+ Object_Definition =>
New_Copy_Tree (Object_Definition (Parent (Targ1))));
Replace_Formals (Decl);
Decl :=
Make_Object_Declaration (Loc,
Defining_Identifier => Temp,
- Object_Definition =>
- New_Occurrence_Of (Ret_Type, Loc));
+ Object_Definition => New_Occurrence_Of (Ret_Type, Loc));
Set_Etype (Temp, Ret_Type);
end if;
Replace_Formals (Blk);
Set_Parent (Blk, N);
- if not Comes_From_Source (Subp)
- or else Is_Predef
- then
+ if not Comes_From_Source (Subp) or else Is_Predef then
Reset_Slocs (Blk);
end if;
if Num_Ret = 1
and then
Nkind (Last (Statements (Handled_Statement_Sequence (Blk)))) =
- N_Goto_Statement
+ N_Goto_Statement
then
Remove (Last (Statements (Handled_Statement_Sequence (Blk))));
else
if Ekind (Subp) = E_Procedure then
Rewrite_Procedure_Call (N, Blk);
+
else
Rewrite_Function_Call (N, Blk);
Par_Func : constant Entity_Id :=
Return_Applies_To (Return_Statement_Entity (N));
+ Result_Subt : constant Entity_Id := Etype (Par_Func);
Ret_Obj_Id : constant Entity_Id :=
First_Entity (Return_Statement_Entity (N));
Ret_Obj_Decl : constant Node_Id := Parent (Ret_Obj_Id);
Alloc_Expr : Node_Id) return Node_Id
is
begin
+ pragma Assert (Is_Build_In_Place_Function (Func_Id));
+
-- Processing for build-in-place object allocation. This is disabled
-- on .NET/JVM because the targets do not support pools.
if VM_Target = No_VM
- and then Is_Build_In_Place_Function (Func_Id)
and then Needs_Finalization (Ret_Typ)
then
declare
Build_In_Place_Formal
(Func_Id, BIP_Finalization_Master);
Stmts : constant List_Id := New_List;
-
- Local_Id : Entity_Id;
- Pool_Id : Entity_Id;
- Ptr_Typ : Entity_Id;
+ Desig_Typ : Entity_Id;
+ Local_Id : Entity_Id;
+ Pool_Id : Entity_Id;
+ Ptr_Typ : Entity_Id;
begin
-- Generate:
-- of the temporary. Otherwise the secondary stack allocation
-- will fail.
+ Desig_Typ := Ret_Typ;
+
+ -- Ensure that the build-in-place machinery uses a fat pointer
+ -- when allocating an unconstrained array on the heap. In this
+ -- case the result object type is a constrained array type even
+ -- though the function type is unconstrained.
+
+ if Ekind (Desig_Typ) = E_Array_Subtype then
+ Desig_Typ := Base_Type (Desig_Typ);
+ end if;
+
-- Generate:
- -- type Ptr_Typ is access Ret_Typ;
+ -- type Ptr_Typ is access Desig_Typ;
Ptr_Typ := Make_Temporary (Loc, 'P');
Type_Definition =>
Make_Access_To_Object_Definition (Loc,
Subtype_Indication =>
- New_Reference_To (Ret_Typ, Loc))));
+ New_Reference_To (Desig_Typ, Loc))));
-- Perform minor decoration in order to set the master and the
-- storage pool attributes.
Set_Associated_Storage_Pool (Ptr_Typ, Pool_Id);
-- Create the temporary, generate:
- --
-- Local_Id : Ptr_Typ;
Local_Id := Make_Temporary (Loc, 'T');
New_Reference_To (Ptr_Typ, Loc)));
-- Allocate the object, generate:
- --
-- Local_Id := <Alloc_Expr>;
Append_To (Stmts,
end;
-- For all other cases, generate:
- --
-- Temp_Id := <Alloc_Expr>;
else
---------------------------
function Move_Activation_Chain return Node_Id is
- Chain_Formal : constant Entity_Id :=
- Build_In_Place_Formal
- (Par_Func, BIP_Activation_Chain);
- To : constant Node_Id :=
- New_Reference_To (Chain_Formal, Loc);
- Master_Formal : constant Entity_Id :=
- Build_In_Place_Formal (Par_Func, BIP_Master);
- New_Master : constant Node_Id :=
- New_Reference_To (Master_Formal, Loc);
-
- Chain_Id : Entity_Id;
- From : Node_Id;
-
begin
- Chain_Id := First_Entity (Return_Statement_Entity (N));
- while Chars (Chain_Id) /= Name_uChain loop
- Chain_Id := Next_Entity (Chain_Id);
- end loop;
-
- From :=
- Make_Attribute_Reference (Loc,
- Prefix =>
- New_Reference_To (Chain_Id, Loc),
- Attribute_Name => Name_Unrestricted_Access);
- -- ??? Not clear why "Make_Identifier (Loc, Name_uChain)" doesn't
- -- work, instead of "New_Reference_To (Chain_Id, Loc)" above.
-
return
Make_Procedure_Call_Statement (Loc,
Name =>
New_Reference_To (RTE (RE_Move_Activation_Chain), Loc),
- Parameter_Associations => New_List (From, To, New_Master));
+
+ Parameter_Associations => New_List (
+
+ -- Source chain
+
+ Make_Attribute_Reference (Loc,
+ Prefix => Make_Identifier (Loc, Name_uChain),
+ Attribute_Name => Name_Unrestricted_Access),
+
+ -- Destination chain
+
+ New_Reference_To
+ (Build_In_Place_Formal (Par_Func, BIP_Activation_Chain), Loc),
+
+ -- New master
+
+ New_Reference_To
+ (Build_In_Place_Formal (Par_Func, BIP_Task_Master), Loc)));
end Move_Activation_Chain;
-- Start of processing for Expand_N_Extended_Return_Statement
-- Recover the function body
Func_Bod := Unit_Declaration_Node (Par_Func);
+
if Nkind (Func_Bod) = N_Subprogram_Declaration then
Func_Bod := Parent (Parent (Corresponding_Body (Func_Bod)));
end if;
-- built in place (though we plan to do so eventually).
if Present (HSS)
- or else Is_Composite_Type (Etype (Par_Func))
+ or else Is_Composite_Type (Result_Subt)
or else No (Exp)
then
if No (HSS) then
-- the case of result types with task parts.
if Is_Build_In_Place
- and then Has_Task (Etype (Par_Func))
+ and then Has_Task (Result_Subt)
then
- Append_To (Stmts, Move_Activation_Chain);
+ -- The return expression is an aggregate for a complex type which
+ -- contains tasks. This particular case is left unexpanded since
+ -- the regular expansion would insert all temporaries and
+ -- initialization code in the wrong block.
+
+ if Nkind (Exp) = N_Aggregate then
+ Expand_N_Aggregate (Exp);
+ end if;
+
+ -- Do not move the activation chain if the return object does not
+ -- contain tasks.
+
+ if Has_Task (Etype (Ret_Obj_Id)) then
+ Append_To (Stmts, Move_Activation_Chain);
+ end if;
end if;
-- Update the state of the function right before the object is
Set_Identifier
(Result, New_Occurrence_Of (Return_Statement_Entity (N), Loc));
- -- If the object decl was already rewritten as a renaming, then
- -- we don't want to do the object allocation and transformation of
- -- of the return object declaration to a renaming. This case occurs
+ -- If the object decl was already rewritten as a renaming, then we
+ -- don't want to do the object allocation and transformation of of
+ -- the return object declaration to a renaming. This case occurs
-- when the return object is initialized by a call to another
- -- build-in-place function, and that function is responsible for the
- -- allocation of the return object.
+ -- build-in-place function, and that function is responsible for
+ -- the allocation of the return object.
if Is_Build_In_Place
and then Nkind (Ret_Obj_Decl) = N_Object_Renaming_Declaration
Return_Obj_Typ : constant Entity_Id := Etype (Return_Obj_Id);
Return_Obj_Expr : constant Node_Id :=
Expression (Ret_Obj_Decl);
- Result_Subt : constant Entity_Id := Etype (Par_Func);
Constr_Result : constant Boolean :=
Is_Constrained (Result_Subt);
Obj_Alloc_Formal : Entity_Id;
Build_In_Place_Formal (Par_Func, BIP_Alloc_Form);
declare
- Ref_Type : Entity_Id;
- Ptr_Type_Decl : Node_Id;
+ Pool_Id : constant Entity_Id :=
+ Make_Temporary (Loc, 'P');
Alloc_Obj_Id : Entity_Id;
Alloc_Obj_Decl : Node_Id;
Alloc_If_Stmt : Node_Id;
Heap_Allocator : Node_Id;
+ Pool_Decl : Node_Id;
+ Pool_Allocator : Node_Id;
+ Ptr_Type_Decl : Node_Id;
+ Ref_Type : Entity_Id;
SS_Allocator : Node_Id;
begin
Set_No_Initialization (Heap_Allocator);
end if;
+ -- The Pool_Allocator is just like the Heap_Allocator,
+ -- except we set Storage_Pool and Procedure_To_Call so
+ -- it will use the user-defined storage pool.
+
+ Pool_Allocator := New_Copy_Tree (Heap_Allocator);
+
+ -- Do not generate the renaming of the build-in-place
+ -- pool parameter on .NET/JVM/ZFP because the parameter
+ -- is not created in the first place.
+
+ if VM_Target = No_VM
+ and then RTE_Available (RE_Root_Storage_Pool_Ptr)
+ then
+ Pool_Decl :=
+ Make_Object_Renaming_Declaration (Loc,
+ Defining_Identifier => Pool_Id,
+ Subtype_Mark =>
+ New_Reference_To
+ (RTE (RE_Root_Storage_Pool), Loc),
+ Name =>
+ Make_Explicit_Dereference (Loc,
+ New_Reference_To
+ (Build_In_Place_Formal
+ (Par_Func, BIP_Storage_Pool), Loc)));
+ Set_Storage_Pool (Pool_Allocator, Pool_Id);
+ Set_Procedure_To_Call
+ (Pool_Allocator, RTE (RE_Allocate_Any));
+ else
+ Pool_Decl := Make_Null_Statement (Loc);
+ end if;
+
-- If the No_Allocators restriction is active, then only
-- an allocator for secondary stack allocation is needed.
-- It's OK for such allocators to have Comes_From_Source
if Restriction_Active (No_Allocators) then
SS_Allocator := Heap_Allocator;
Heap_Allocator := Make_Null (Loc);
+ Pool_Allocator := Make_Null (Loc);
- -- Otherwise the heap allocator may be needed, so we make
- -- another allocator for secondary stack allocation.
+ -- Otherwise the heap and pool allocators may be needed,
+ -- so we make another allocator for secondary stack
+ -- allocation.
else
SS_Allocator := New_Copy_Tree (Heap_Allocator);
- -- The heap allocator is marked Comes_From_Source
- -- since it corresponds to an explicit user-written
- -- allocator (that is, it will only be executed on
- -- behalf of callers that call the function as
- -- initialization for such an allocator). This
- -- prevents errors when No_Implicit_Heap_Allocations
+ -- The heap and pool allocators are marked as
+ -- Comes_From_Source since they correspond to an
+ -- explicit user-written allocator (that is, it will
+ -- only be executed on behalf of callers that call the
+ -- function as initialization for such an allocator).
+ -- Prevents errors when No_Implicit_Heap_Allocations
-- is in force.
Set_Comes_From_Source (Heap_Allocator, True);
+ Set_Comes_From_Source (Pool_Allocator, True);
end if;
-- The allocator is returned on the secondary stack. We
-- The allocator is returned on the secondary stack,
-- so indicate that the function return, as well as
-- the block that encloses the allocator, must not
- -- release it. The flags must be set now because the
- -- decision to use the secondary stack is done very
- -- late in the course of expanding the return
+ -- release it. The flags must be set now because
+ -- the decision to use the secondary stack is done
+ -- very late in the course of expanding the return
-- statement, past the point where these flags are
-- normally set.
-- Create an if statement to test the BIP_Alloc_Form
-- formal and initialize the access object to either the
- -- BIP_Object_Access formal (BIP_Alloc_Form = 0), the
- -- result of allocating the object in the secondary stack
- -- (BIP_Alloc_Form = 1), or else an allocator to create
- -- the return object in the heap (BIP_Alloc_Form = 2).
+ -- BIP_Object_Access formal (BIP_Alloc_Form =
+ -- Caller_Allocation), the result of allocating the
+ -- object in the secondary stack (BIP_Alloc_Form =
+ -- Secondary_Stack), or else an allocator to create the
+ -- return object in the heap or user-defined pool
+ -- (BIP_Alloc_Form = Global_Heap or User_Storage_Pool).
-- ??? An unchecked type conversion must be made in the
-- case of assigning the access object formal to the
Make_Assignment_Statement (Loc,
Name =>
New_Reference_To (Alloc_Obj_Id, Loc),
- Expression => SS_Allocator)))),
+ Expression => SS_Allocator))),
+
+ Make_Elsif_Part (Loc,
+ Condition =>
+ Make_Op_Eq (Loc,
+ Left_Opnd =>
+ New_Reference_To (Obj_Alloc_Formal, Loc),
+ Right_Opnd =>
+ Make_Integer_Literal (Loc,
+ UI_From_Int (BIP_Allocation_Form'Pos
+ (Global_Heap)))),
+
+ Then_Statements => New_List (
+ Build_Heap_Allocator
+ (Temp_Id => Alloc_Obj_Id,
+ Temp_Typ => Ref_Type,
+ Func_Id => Par_Func,
+ Ret_Typ => Return_Obj_Typ,
+ Alloc_Expr => Heap_Allocator)))),
Else_Statements => New_List (
+ Pool_Decl,
Build_Heap_Allocator
(Temp_Id => Alloc_Obj_Id,
Temp_Typ => Ref_Type,
Func_Id => Par_Func,
Ret_Typ => Return_Obj_Typ,
- Alloc_Expr => Heap_Allocator)));
+ Alloc_Expr => Pool_Allocator)));
-- If a separate initialization assignment was created
-- earlier, append that following the assignment of the
-- implicit access formal to the access object, to ensure
- -- that the return object is initialized in that case.
- -- In this situation, the target of the assignment must
- -- be rewritten to denote a dereference of the access to
- -- the return object passed in by the caller.
+ -- that the return object is initialized in that case. In
+ -- this situation, the target of the assignment must be
+ -- rewritten to denote a dereference of the access to the
+ -- return object passed in by the caller.
if Present (Init_Assignment) then
Rewrite (Name (Init_Assignment),
end if;
-- If local-exception-to-goto optimization active, insert dummy push
- -- statements at start, and dummy pop statements at end.
+ -- statements at start, and dummy pop statements at end, but inhibit
+ -- this if we have No_Exception_Handlers, since they are useless and
+ -- intefere with analysis, e.g. by codepeer.
if (Debug_Flag_Dot_G
or else Restriction_Active (No_Exception_Propagation))
+ and then not Restriction_Active (No_Exception_Handlers)
+ and then not CodePeer_Mode
and then Is_Non_Empty_List (L)
then
declare
Pop_Scope;
end if;
- -- Ada 2005 (AI-348): Generate body for a null procedure.
- -- In most cases this is superfluous because calls to it
- -- will be automatically inlined, but we definitely need
- -- the body if preconditions for the procedure are present.
+ -- Ada 2005 (AI-348): Generate body for a null procedure. In most
+ -- cases this is superfluous because calls to it will be automatically
+ -- inlined, but we definitely need the body if preconditions for the
+ -- procedure are present.
elsif Nkind (Specification (N)) = N_Procedure_Specification
and then Null_Present (Specification (N))
begin
-- Call _Postconditions procedure if procedure with active
- -- postconditions. Here, we use the Postcondition_Proc attribute, which
- -- is needed for implicitly-generated returns. Functions never
- -- have implicitly-generated returns, and there's no room for
- -- Postcondition_Proc in E_Function, so we look up the identifier
- -- Name_uPostconditions for function returns (see
+ -- postconditions. Here, we use the Postcondition_Proc attribute,
+ -- which is needed for implicitly-generated returns. Functions
+ -- never have implicitly-generated returns, and there's no
+ -- room for Postcondition_Proc in E_Function, so we look up the
+ -- identifier Name_uPostconditions for function returns (see
-- Expand_Simple_Function_Return).
if Ekind (Scope_Id) = E_Procedure
Rec : Node_Id;
begin
- -- If the protected object is not an enclosing scope, this is an
- -- inter-object function call. Inter-object procedure calls are expanded
- -- by Exp_Ch9.Build_Simple_Entry_Call. The call is intra-object only if
- -- the subprogram being called is in the protected body being compiled,
- -- and if the protected object in the call is statically the enclosing
- -- type. The object may be an component of some other data structure, in
- -- which case this must be handled as an inter-object call.
+ -- If the protected object is not an enclosing scope, this is an inter-
+ -- object function call. Inter-object procedure calls are expanded by
+ -- Exp_Ch9.Build_Simple_Entry_Call. The call is intra-object only if the
+ -- subprogram being called is in the protected body being compiled, and
+ -- if the protected object in the call is statically the enclosing type.
+ -- The object may be an component of some other data structure, in which
+ -- case this must be handled as an inter-object call.
if not In_Open_Scopes (Scop)
or else not Is_Entity_Name (Name (N))
Build_Protected_Subprogram_Call (N,
Name => New_Occurrence_Of (Subp, Sloc (N)),
- Rec => Convert_Concurrent (Rec, Etype (Rec)),
+ Rec => Convert_Concurrent (Rec, Etype (Rec)),
External => True);
else
end if;
end Expand_Protected_Subprogram_Call;
+ --------------------------------------------
+ -- Has_Unconstrained_Access_Discriminants --
+ --------------------------------------------
+
+ function Has_Unconstrained_Access_Discriminants
+ (Subtyp : Entity_Id) return Boolean
+ is
+ Discr : Entity_Id;
+
+ begin
+ if Has_Discriminants (Subtyp)
+ and then not Is_Constrained (Subtyp)
+ then
+ Discr := First_Discriminant (Subtyp);
+ while Present (Discr) loop
+ if Ekind (Etype (Discr)) = E_Anonymous_Access_Type then
+ return True;
+ end if;
+
+ Next_Discriminant (Discr);
+ end loop;
+ end if;
+
+ return False;
+ end Has_Unconstrained_Access_Discriminants;
+
-----------------------------------
-- Expand_Simple_Function_Return --
-----------------------------------
- -- The "simple" comes from the syntax rule simple_return_statement.
- -- The semantics are not at all simple!
+ -- The "simple" comes from the syntax rule simple_return_statement. The
+ -- semantics are not at all simple!
procedure Expand_Simple_Function_Return (N : Node_Id) is
Loc : constant Source_Ptr := Sloc (N);
-- The type of the expression (not necessarily the same as R_Type)
Subtype_Ind : Node_Id;
- -- If the result type of the function is class-wide and the
- -- expression has a specific type, then we use the expression's
- -- type as the type of the return object. In cases where the
- -- expression is an aggregate that is built in place, this avoids
- -- the need for an expensive conversion of the return object to
- -- the specific type on assignments to the individual components.
+ -- If the result type of the function is class-wide and the expression
+ -- has a specific type, then we use the expression's type as the type of
+ -- the return object. In cases where the expression is an aggregate that
+ -- is built in place, this avoids the need for an expensive conversion
+ -- of the return object to the specific type on assignments to the
+ -- individual components.
begin
if Is_Class_Wide_Type (R_Type)
-- Optimize the case where the result is a function call. In this
-- case either the result is already on the secondary stack, or is
-- already being returned with the stack pointer depressed and no
- -- further processing is required except to set the By_Ref flag to
- -- ensure that gigi does not attempt an extra unnecessary copy.
+ -- further processing is required except to set the By_Ref flag
+ -- to ensure that gigi does not attempt an extra unnecessary copy.
-- (actually not just unnecessary but harmfully wrong in the case
-- of a controlled type, where gigi does not know how to do a copy).
- -- To make up for a gcc 2.8.1 deficiency (???), we perform
- -- the copy for array types if the constrained status of the
- -- target type is different from that of the expression.
+ -- To make up for a gcc 2.8.1 deficiency (???), we perform the copy
+ -- for array types if the constrained status of the target type is
+ -- different from that of the expression.
if Requires_Transient_Scope (Exptyp)
and then
Make_Explicit_Dereference (Loc,
Prefix => New_Reference_To (Temp, Loc)));
+ -- Ada 2005 (AI-251): If the type of the returned object is
+ -- an interface then add an implicit type conversion to force
+ -- displacement of the "this" pointer.
+
+ if Is_Interface (R_Type) then
+ Rewrite (Exp, Convert_To (R_Type, Relocate_Node (Exp)));
+ end if;
+
Analyze_And_Resolve (Exp, R_Type);
end;
end if;
end if;
- -- Implement the rules of 6.5(8-10), which require a tag check in the
- -- case of a limited tagged return type, and tag reassignment for
+ -- Implement the rules of 6.5(8-10), which require a tag check in
+ -- the case of a limited tagged return type, and tag reassignment for
-- nonlimited tagged results. These actions are needed when the return
-- type is a specific tagged type and the result expression is a
- -- conversion or a formal parameter, because in that case the tag of the
- -- expression might differ from the tag of the specific result type.
+ -- conversion or a formal parameter, because in that case the tag of
+ -- the expression might differ from the tag of the specific result type.
if Is_Tagged_Type (Utyp)
and then not Is_Class_Wide_Type (Utyp)
or else (Is_Entity_Name (Exp)
and then Ekind (Entity (Exp)) in Formal_Kind))
then
- -- When the return type is limited, perform a check that the
- -- tag of the result is the same as the tag of the return type.
+ -- When the return type is limited, perform a check that the tag of
+ -- the result is the same as the tag of the return type.
if Is_Limited_Type (R_Type) then
Insert_Action (Exp,
-- If the result type is a specific nonlimited tagged type, then we
-- have to ensure that the tag of the result is that of the result
- -- type. This is handled by making a copy of the expression in the
- -- case where it might have a different tag, namely when the
+ -- type. This is handled by making a copy of the expression in
+ -- the case where it might have a different tag, namely when the
-- expression is a conversion or a formal parameter. We create a new
-- object of the result type and initialize it from the expression,
-- which will implicitly force the tag to be set appropriately.
begin
-- Ada 2005 (AI-251): In class-wide interface objects we displace
- -- "this" to reference the base of the object --- required to get
- -- access to the TSD of the object.
+ -- "this" to reference the base of the object. This is required to
+ -- get access to the TSD of the object.
if Is_Class_Wide_Type (Etype (Exp))
and then Is_Interface (Etype (Exp))
Make_Op_Ne (Loc,
Left_Opnd => Duplicate_Subexpr (Exp),
Right_Opnd => Make_Null (Loc)),
+
Right_Opnd => Make_Op_Ne (Loc,
Left_Opnd =>
Make_Selected_Component (Loc,
Prefix => Duplicate_Subexpr (Exp),
Selector_Name => Make_Identifier (Loc, Name_uTag)),
+
Right_Opnd =>
Make_Attribute_Reference (Loc,
Prefix =>
New_Occurrence_Of (Designated_Type (R_Type), Loc),
Attribute_Name => Name_Tag))),
+
Reason => CE_Tag_Check_Failed),
Suppress => All_Checks);
end if;
+ -- AI05-0234: RM 6.5(21/3). Check access discriminants to
+ -- ensure that the function result does not outlive an
+ -- object designated by one of it discriminants.
+
+ if Present (Extra_Accessibility_Of_Result (Scope_Id))
+ and then Has_Unconstrained_Access_Discriminants (R_Type)
+ then
+ declare
+ Discrim_Source : Node_Id;
+
+ procedure Check_Against_Result_Level (Level : Node_Id);
+ -- Check the given accessibility level against the level
+ -- determined by the point of call. (AI05-0234).
+
+ --------------------------------
+ -- Check_Against_Result_Level --
+ --------------------------------
+
+ procedure Check_Against_Result_Level (Level : Node_Id) is
+ begin
+ Insert_Action (N,
+ Make_Raise_Program_Error (Loc,
+ Condition =>
+ Make_Op_Gt (Loc,
+ Left_Opnd => Level,
+ Right_Opnd =>
+ New_Occurrence_Of
+ (Extra_Accessibility_Of_Result (Scope_Id), Loc)),
+ Reason => PE_Accessibility_Check_Failed));
+ end Check_Against_Result_Level;
+
+ begin
+ Discrim_Source := Exp;
+ while Nkind (Discrim_Source) = N_Qualified_Expression loop
+ Discrim_Source := Expression (Discrim_Source);
+ end loop;
+
+ if Nkind (Discrim_Source) = N_Identifier
+ and then Is_Return_Object (Entity (Discrim_Source))
+ then
+ Discrim_Source := Entity (Discrim_Source);
+
+ if Is_Constrained (Etype (Discrim_Source)) then
+ Discrim_Source := Etype (Discrim_Source);
+ else
+ Discrim_Source := Expression (Parent (Discrim_Source));
+ end if;
+
+ elsif Nkind (Discrim_Source) = N_Identifier
+ and then Nkind_In (Original_Node (Discrim_Source),
+ N_Aggregate, N_Extension_Aggregate)
+ then
+ Discrim_Source := Original_Node (Discrim_Source);
+
+ elsif Nkind (Discrim_Source) = N_Explicit_Dereference and then
+ Nkind (Original_Node (Discrim_Source)) = N_Function_Call
+ then
+ Discrim_Source := Original_Node (Discrim_Source);
+ end if;
+
+ while Nkind_In (Discrim_Source, N_Qualified_Expression,
+ N_Type_Conversion,
+ N_Unchecked_Type_Conversion)
+ loop
+ Discrim_Source := Expression (Discrim_Source);
+ end loop;
+
+ case Nkind (Discrim_Source) is
+ when N_Defining_Identifier =>
+
+ pragma Assert (Is_Composite_Type (Discrim_Source)
+ and then Has_Discriminants (Discrim_Source)
+ and then Is_Constrained (Discrim_Source));
+
+ declare
+ Discrim : Entity_Id :=
+ First_Discriminant (Base_Type (R_Type));
+ Disc_Elmt : Elmt_Id :=
+ First_Elmt (Discriminant_Constraint
+ (Discrim_Source));
+ begin
+ loop
+ if Ekind (Etype (Discrim)) =
+ E_Anonymous_Access_Type
+ then
+ Check_Against_Result_Level
+ (Dynamic_Accessibility_Level (Node (Disc_Elmt)));
+ end if;
+
+ Next_Elmt (Disc_Elmt);
+ Next_Discriminant (Discrim);
+ exit when not Present (Discrim);
+ end loop;
+ end;
+
+ when N_Aggregate | N_Extension_Aggregate =>
+
+ -- Unimplemented: extension aggregate case where discrims
+ -- come from ancestor part, not extension part.
+
+ declare
+ Discrim : Entity_Id :=
+ First_Discriminant (Base_Type (R_Type));
+
+ Disc_Exp : Node_Id := Empty;
+
+ Positionals_Exhausted
+ : Boolean := not Present (Expressions
+ (Discrim_Source));
+
+ function Associated_Expr
+ (Comp_Id : Entity_Id;
+ Associations : List_Id) return Node_Id;
+
+ -- Given a component and a component associations list,
+ -- locate the expression for that component; returns
+ -- Empty if no such expression is found.
+
+ ---------------------
+ -- Associated_Expr --
+ ---------------------
+
+ function Associated_Expr
+ (Comp_Id : Entity_Id;
+ Associations : List_Id) return Node_Id
+ is
+ Assoc : Node_Id;
+ Choice : Node_Id;
+
+ begin
+ -- Simple linear search seems ok here
+
+ Assoc := First (Associations);
+ while Present (Assoc) loop
+ Choice := First (Choices (Assoc));
+ while Present (Choice) loop
+ if (Nkind (Choice) = N_Identifier
+ and then Chars (Choice) = Chars (Comp_Id))
+ or else (Nkind (Choice) = N_Others_Choice)
+ then
+ return Expression (Assoc);
+ end if;
+
+ Next (Choice);
+ end loop;
+
+ Next (Assoc);
+ end loop;
+
+ return Empty;
+ end Associated_Expr;
+
+ -- Start of processing for Expand_Simple_Function_Return
+
+ begin
+ if not Positionals_Exhausted then
+ Disc_Exp := First (Expressions (Discrim_Source));
+ end if;
+
+ loop
+ if Positionals_Exhausted then
+ Disc_Exp :=
+ Associated_Expr
+ (Discrim,
+ Component_Associations (Discrim_Source));
+ end if;
+
+ if Ekind (Etype (Discrim)) =
+ E_Anonymous_Access_Type
+ then
+ Check_Against_Result_Level
+ (Dynamic_Accessibility_Level (Disc_Exp));
+ end if;
+
+ Next_Discriminant (Discrim);
+ exit when not Present (Discrim);
+
+ if not Positionals_Exhausted then
+ Next (Disc_Exp);
+ Positionals_Exhausted := not Present (Disc_Exp);
+ end if;
+ end loop;
+ end;
+
+ when N_Function_Call =>
+
+ -- No check needed (check performed by callee)
+
+ null;
+
+ when others =>
+
+ declare
+ Level : constant Node_Id :=
+ Make_Integer_Literal (Loc,
+ Object_Access_Level (Discrim_Source));
+
+ begin
+ -- Unimplemented: check for name prefix that includes
+ -- a dereference of an access value with a dynamic
+ -- accessibility level (e.g., an access param or a
+ -- saooaaat) and use dynamic level in that case. For
+ -- example:
+ -- return Access_Param.all(Some_Index).Some_Component;
+ -- ???
+
+ Set_Etype (Level, Standard_Natural);
+ Check_Against_Result_Level (Level);
+ end;
+
+ end case;
+ end;
+ end if;
+
-- If we are returning an object that may not be bit-aligned, then copy
-- the value into a temporary first. This copy may need to expand to a
-- loop of component operations.
Function_Id : Entity_Id;
begin
+ -- Return False when the expander is inactive, since awareness of
+ -- build-in-place treatment is only relevant during expansion. Note that
+ -- Is_Build_In_Place_Function, which is called as part of this function,
+ -- is also conditioned this way, but we need to check here as well to
+ -- avoid blowing up on processing protected calls when expansion is
+ -- disabled (such as with -gnatc) since those would trip over the raise
+ -- of Program_Error below.
+
+ if not Expander_Active then
+ return False;
+ end if;
+
-- Step past qualification or unchecked conversion (the latter can occur
-- in cases of calls to 'Input).
- if Nkind_In
- (Exp_Node, N_Qualified_Expression, N_Unchecked_Type_Conversion)
+ if Nkind_In (Exp_Node, N_Qualified_Expression,
+ N_Unchecked_Type_Conversion)
then
Exp_Node := Expression (N);
end if;
return False;
else
- if Is_Entity_Name (Name (Exp_Node)) then
+ -- In Alfa mode, build-in-place calls are not expanded, so that we
+ -- may end up with a call that is neither resolved to an entity, nor
+ -- an indirect call.
+
+ if Alfa_Mode then
+ return False;
+
+ elsif Is_Entity_Name (Name (Exp_Node)) then
Function_Id := Entity (Name (Exp_Node));
+ -- In the case of an explicitly dereferenced call, use the subprogram
+ -- type generated for the dereference.
+
elsif Nkind (Name (Exp_Node)) = N_Explicit_Dereference then
Function_Id := Etype (Name (Exp_Node));
+
+ else
+ raise Program_Error;
end if;
return Is_Build_In_Place_Function (Function_Id);
Thunk_Code,
Build_Set_Predefined_Prim_Op_Address (Loc,
- Tag_Node =>
+ Tag_Node =>
New_Reference_To (Node (Next_Elmt (Iface_DT_Ptr)), Loc),
- Position => DT_Position (Prim),
+ Position => DT_Position (Prim),
Address_Node =>
Unchecked_Convert_To (RTE (RE_Prim_Ptr),
Make_Attribute_Reference (Loc,
Attribute_Name => Name_Unrestricted_Access))),
Build_Set_Predefined_Prim_Op_Address (Loc,
- Tag_Node =>
+ Tag_Node =>
New_Reference_To
(Node (Next_Elmt (Next_Elmt (Next_Elmt (Iface_DT_Ptr)))),
Loc),
- Position => DT_Position (Prim),
+ Position => DT_Position (Prim),
Address_Node =>
Unchecked_Convert_To (RTE (RE_Prim_Ptr),
Make_Attribute_Reference (Loc,
Next_Elmt (Iface_DT_Ptr);
pragma Assert (Has_Thunks (Node (Iface_DT_Ptr)));
- -- Skip the tag of the no-thunks dispatch table
+ -- Skip tag of the no-thunks dispatch table
Next_Elmt (Iface_DT_Ptr);
pragma Assert (not Has_Thunks (Node (Iface_DT_Ptr)));
- -- Skip the tag of the predefined primitives no-thunks dispatch
- -- table.
+ -- Skip tag of predefined primitives no-thunks dispatch table
Next_Elmt (Iface_DT_Ptr);
pragma Assert (not Has_Thunks (Node (Iface_DT_Ptr)));
-- slots.
elsif Is_Imported (Subp)
- and then (Convention (Subp) = Convention_CPP
- or else Convention (Subp) = Convention_C)
+ and then (Convention (Subp) = Convention_CPP
+ or else Convention (Subp) = Convention_C)
then
null;
(Allocator : Node_Id;
Function_Call : Node_Id)
is
+ Acc_Type : constant Entity_Id := Etype (Allocator);
Loc : Source_Ptr;
Func_Call : Node_Id := Function_Call;
Function_Id : Entity_Id;
Result_Subt : Entity_Id;
- Acc_Type : constant Entity_Id := Etype (Allocator);
New_Allocator : Node_Id;
Return_Obj_Access : Entity_Id;
raise Program_Error;
end if;
- Result_Subt := Etype (Function_Id);
+ Result_Subt := Available_View (Etype (Function_Id));
+
+ -- Check whether return type includes tasks. This may not have been done
+ -- previously, if the type was a limited view.
+
+ if Has_Task (Result_Subt) then
+ Build_Activation_Chain_Entity (Allocator);
+ end if;
-- When the result subtype is constrained, the return object must be
-- allocated on the caller side, and access to it is passed to the
-- called as a dispatching operation and must be treated similarly
-- to functions with unconstrained result subtypes.
- Add_Alloc_Form_Actual_To_Build_In_Place_Call
+ Add_Unconstrained_Actuals_To_Build_In_Place_Call
(Func_Call, Function_Id, Alloc_Form => Caller_Allocation);
Add_Finalization_Master_Actual_To_Build_In_Place_Call
-- operations. ???
else
- -- Pass an allocation parameter indicating that the function should
- -- allocate its result on the heap.
+ -- Case of a user-defined storage pool. Pass an allocation parameter
+ -- indicating that the function should allocate its result in the
+ -- pool, and pass the pool. Use 'Unrestricted_Access because the
+ -- pool may not be aliased.
+
+ if VM_Target = No_VM
+ and then Present (Associated_Storage_Pool (Acc_Type))
+ then
+ Add_Unconstrained_Actuals_To_Build_In_Place_Call
+ (Func_Call, Function_Id, Alloc_Form => User_Storage_Pool,
+ Pool_Actual =>
+ Make_Attribute_Reference (Loc,
+ Prefix =>
+ New_Reference_To
+ (Associated_Storage_Pool (Acc_Type), Loc),
+ Attribute_Name => Name_Unrestricted_Access));
+
+ -- No user-defined pool; pass an allocation parameter indicating that
+ -- the function should allocate its result on the heap.
- Add_Alloc_Form_Actual_To_Build_In_Place_Call
- (Func_Call, Function_Id, Alloc_Form => Global_Heap);
+ else
+ Add_Unconstrained_Actuals_To_Build_In_Place_Call
+ (Func_Call, Function_Id, Alloc_Form => Global_Heap);
+ end if;
Add_Finalization_Master_Actual_To_Build_In_Place_Call
(Func_Call, Function_Id, Acc_Type);
then
null;
- -- Do not generate the call to Make_Set_Finalize_Address for
- -- CodePeer compilations because Finalize_Address is never built.
+ -- Do not generate the call to Set_Finalize_Address in Alfa mode
+ -- because it is not necessary and results in unwanted expansion.
+ -- This expansion is also not carried out in CodePeer mode because
+ -- Finalize_Address is never built.
- elsif not CodePeer_Mode then
+ elsif not Alfa_Mode
+ and then not CodePeer_Mode
+ then
Insert_Action (Allocator,
Make_Set_Finalize_Address_Call (Loc,
Typ => Etype (Function_Id),
-- to the object created by the allocator).
Rewrite (Allocator, Make_Reference (Loc, Relocate_Node (Function_Call)));
+
+ -- Ada 2005 (AI-251): If the type of the allocator is an interface then
+ -- generate an implicit conversion to force displacement of the "this"
+ -- pointer.
+
+ if Is_Interface (Designated_Type (Acc_Type)) then
+ Rewrite (Allocator, Convert_To (Acc_Type, Relocate_Node (Allocator)));
+ end if;
+
Analyze_And_Resolve (Allocator, Acc_Type);
end Make_Build_In_Place_Call_In_Allocator;
-- called as a dispatching operation and must be treated similarly
-- to functions with unconstrained result subtypes.
- Add_Alloc_Form_Actual_To_Build_In_Place_Call
+ Add_Unconstrained_Actuals_To_Build_In_Place_Call
(Func_Call, Function_Id, Alloc_Form => Caller_Allocation);
Add_Finalization_Master_Actual_To_Build_In_Place_Call
-- Pass an allocation parameter indicating that the function should
-- allocate its result on the secondary stack.
- Add_Alloc_Form_Actual_To_Build_In_Place_Call
+ Add_Unconstrained_Actuals_To_Build_In_Place_Call
(Func_Call, Function_Id, Alloc_Form => Secondary_Stack);
Add_Finalization_Master_Actual_To_Build_In_Place_Call
Obj_Id : Entity_Id;
Ptr_Typ : Entity_Id;
Ptr_Typ_Decl : Node_Id;
+ New_Expr : Node_Id;
Result_Subt : Entity_Id;
Target : Node_Id;
-- controlling result, because dispatching calls to the function needs
-- to be treated effectively the same as calls to class-wide functions.
- Add_Alloc_Form_Actual_To_Build_In_Place_Call
+ Add_Unconstrained_Actuals_To_Build_In_Place_Call
(Func_Call, Func_Id, Alloc_Form => Caller_Allocation);
Add_Finalization_Master_Actual_To_Build_In_Place_Call
Insert_After_And_Analyze (Assign, Ptr_Typ_Decl);
-- Finally, create an access object initialized to a reference to the
- -- function call.
+ -- function call. We know this access value is non-null, so mark the
+ -- entity accordingly to suppress junk access checks.
- Obj_Id := Make_Temporary (Loc, 'R');
+ New_Expr := Make_Reference (Loc, Relocate_Node (Func_Call));
+
+ Obj_Id := Make_Temporary (Loc, 'R', New_Expr);
Set_Etype (Obj_Id, Ptr_Typ);
+ Set_Is_Known_Non_Null (Obj_Id);
Obj_Decl :=
Make_Object_Declaration (Loc,
Defining_Identifier => Obj_Id,
Object_Definition => New_Reference_To (Ptr_Typ, Loc),
- Expression => Make_Reference (Loc, Relocate_Node (Func_Call)));
+ Expression => New_Expr);
Insert_After_And_Analyze (Ptr_Typ_Decl, Obj_Decl);
Rewrite (Assign, Make_Null_Statement (Loc));
Loc : Source_Ptr;
Obj_Def_Id : constant Entity_Id :=
Defining_Identifier (Object_Decl);
-
+ Enclosing_Func : constant Entity_Id :=
+ Enclosing_Subprogram (Obj_Def_Id);
+ Call_Deref : Node_Id;
+ Caller_Object : Node_Id;
+ Def_Id : Entity_Id;
+ Fmaster_Actual : Node_Id := Empty;
Func_Call : Node_Id := Function_Call;
Function_Id : Entity_Id;
- Result_Subt : Entity_Id;
- Caller_Object : Node_Id;
- Call_Deref : Node_Id;
- Ref_Type : Entity_Id;
+ Pool_Actual : Node_Id;
Ptr_Typ_Decl : Node_Id;
- Def_Id : Entity_Id;
- New_Expr : Node_Id;
- Enclosing_Func : Entity_Id;
Pass_Caller_Acc : Boolean := False;
+ New_Expr : Node_Id;
+ Ref_Type : Entity_Id;
+ Result_Subt : Entity_Id;
begin
-- Step past qualification or unchecked conversion (the latter can occur
Result_Subt := Etype (Function_Id);
- -- In the constrained case, add an implicit actual to the function call
- -- that provides access to the declared object. An unchecked conversion
- -- to the (specific) result type of the function is inserted to handle
- -- the case where the object is declared with a class-wide type.
-
- if Is_Constrained (Underlying_Type (Result_Subt)) then
- Caller_Object :=
- Make_Unchecked_Type_Conversion (Loc,
- Subtype_Mark => New_Reference_To (Result_Subt, Loc),
- Expression => New_Reference_To (Obj_Def_Id, Loc));
-
- -- When the function has a controlling result, an allocation-form
- -- parameter must be passed indicating that the caller is allocating
- -- the result object. This is needed because such a function can be
- -- called as a dispatching operation and must be treated similarly
- -- to functions with unconstrained result subtypes.
-
- Add_Alloc_Form_Actual_To_Build_In_Place_Call
- (Func_Call, Function_Id, Alloc_Form => Caller_Allocation);
-
- -- If the function's result subtype is unconstrained and the object is
- -- a return object of an enclosing build-in-place function, then the
- -- implicit build-in-place parameters of the enclosing function must be
- -- passed along to the called function. (Unfortunately, this won't cover
- -- the case of extension aggregates where the ancestor part is a build-
- -- in-place unconstrained function call that should be passed along the
- -- caller's parameters. Currently those get mishandled by reassigning
- -- the result of the call to the aggregate return object, when the call
- -- result should really be directly built in place in the aggregate and
- -- not built in a temporary. ???)
-
- elsif Is_Return_Object (Defining_Identifier (Object_Decl)) then
+ -- If the the object is a return object of an enclosing build-in-place
+ -- function, then the implicit build-in-place parameters of the
+ -- enclosing function are simply passed along to the called function.
+ -- (Unfortunately, this won't cover the case of extension aggregates
+ -- where the ancestor part is a build-in-place unconstrained function
+ -- call that should be passed along the caller's parameters. Currently
+ -- those get mishandled by reassigning the result of the call to the
+ -- aggregate return object, when the call result should really be
+ -- directly built in place in the aggregate and not in a temporary. ???)
+
+ if Is_Return_Object (Defining_Identifier (Object_Decl)) then
Pass_Caller_Acc := True;
- Enclosing_Func := Enclosing_Subprogram (Obj_Def_Id);
+ -- When the enclosing function has a BIP_Alloc_Form formal then we
+ -- pass it along to the callee (such as when the enclosing function
+ -- has an unconstrained or tagged result type).
- -- If the enclosing function has a constrained result type, then
- -- caller allocation will be used.
+ if Needs_BIP_Alloc_Form (Enclosing_Func) then
+ if VM_Target = No_VM and then
+ RTE_Available (RE_Root_Storage_Pool_Ptr)
+ then
+ Pool_Actual :=
+ New_Reference_To (Build_In_Place_Formal
+ (Enclosing_Func, BIP_Storage_Pool), Loc);
- if Is_Constrained (Etype (Enclosing_Func)) then
- Add_Alloc_Form_Actual_To_Build_In_Place_Call
- (Func_Call, Function_Id, Alloc_Form => Caller_Allocation);
+ -- The build-in-place pool formal is not built on .NET/JVM
- -- Otherwise, when the enclosing function has an unconstrained result
- -- type, the BIP_Alloc_Form formal of the enclosing function must be
- -- passed along to the callee.
+ else
+ Pool_Actual := Empty;
+ end if;
- else
- Add_Alloc_Form_Actual_To_Build_In_Place_Call
+ Add_Unconstrained_Actuals_To_Build_In_Place_Call
(Func_Call,
Function_Id,
Alloc_Form_Exp =>
New_Reference_To
(Build_In_Place_Formal (Enclosing_Func, BIP_Alloc_Form),
- Loc));
+ Loc),
+ Pool_Actual => Pool_Actual);
+
+ -- Otherwise, if enclosing function has a constrained result subtype,
+ -- then caller allocation will be used.
+
+ else
+ Add_Unconstrained_Actuals_To_Build_In_Place_Call
+ (Func_Call, Function_Id, Alloc_Form => Caller_Allocation);
+ end if;
+
+ if Needs_BIP_Finalization_Master (Enclosing_Func) then
+ Fmaster_Actual :=
+ New_Reference_To
+ (Build_In_Place_Formal
+ (Enclosing_Func, BIP_Finalization_Master), Loc);
end if;
-- Retrieve the BIPacc formal from the enclosing function and convert
(Build_In_Place_Formal (Enclosing_Func, BIP_Object_Access),
Loc));
+ -- In the constrained case, add an implicit actual to the function call
+ -- that provides access to the declared object. An unchecked conversion
+ -- to the (specific) result type of the function is inserted to handle
+ -- the case where the object is declared with a class-wide type.
+
+ elsif Is_Constrained (Underlying_Type (Result_Subt)) then
+ Caller_Object :=
+ Make_Unchecked_Type_Conversion (Loc,
+ Subtype_Mark => New_Reference_To (Result_Subt, Loc),
+ Expression => New_Reference_To (Obj_Def_Id, Loc));
+
+ -- When the function has a controlling result, an allocation-form
+ -- parameter must be passed indicating that the caller is allocating
+ -- the result object. This is needed because such a function can be
+ -- called as a dispatching operation and must be treated similarly
+ -- to functions with unconstrained result subtypes.
+
+ Add_Unconstrained_Actuals_To_Build_In_Place_Call
+ (Func_Call, Function_Id, Alloc_Form => Caller_Allocation);
+
-- In other unconstrained cases, pass an indication to do the allocation
-- on the secondary stack and set Caller_Object to Empty so that a null
-- value will be passed for the caller's object address. A transient
-- scope is established to ensure eventual cleanup of the result.
else
- Add_Alloc_Form_Actual_To_Build_In_Place_Call
- (Func_Call,
- Function_Id,
- Alloc_Form => Secondary_Stack);
+ Add_Unconstrained_Actuals_To_Build_In_Place_Call
+ (Func_Call, Function_Id, Alloc_Form => Secondary_Stack);
Caller_Object := Empty;
Establish_Transient_Scope (Object_Decl, Sec_Stack => True);
end if;
+ -- Pass along any finalization master actual, which is needed in the
+ -- case where the called function initializes a return object of an
+ -- enclosing build-in-place function.
+
Add_Finalization_Master_Actual_To_Build_In_Place_Call
- (Func_Call, Function_Id);
+ (Func_Call => Func_Call,
+ Func_Id => Function_Id,
+ Master_Exp => Fmaster_Actual);
if Nkind (Parent (Object_Decl)) = N_Extended_Return_Statement
and then Has_Task (Result_Subt)
then
- Enclosing_Func := Enclosing_Subprogram (Obj_Def_Id);
-
-- Here we're passing along the master that was passed in to this
-- function.
Add_Task_Actuals_To_Build_In_Place_Call
(Func_Call, Function_Id,
Master_Actual =>
- New_Reference_To
- (Build_In_Place_Formal (Enclosing_Func, BIP_Master), Loc));
+ New_Reference_To (Build_In_Place_Formal
+ (Enclosing_Func, BIP_Task_Master), Loc));
else
Add_Task_Actuals_To_Build_In_Place_Call
-- The access type and its accompanying object must be inserted after
-- the object declaration in the constrained case, so that the function
-- call can be passed access to the object. In the unconstrained case,
- -- the access type and object must be inserted before the object, since
- -- the object declaration is rewritten to be a renaming of a dereference
- -- of the access object.
+ -- or if the object declaration is for a return object, the access type
+ -- and object must be inserted before the object, since the object
+ -- declaration is rewritten to be a renaming of a dereference of the
+ -- access object.
- if Is_Constrained (Underlying_Type (Result_Subt)) then
+ if Is_Constrained (Underlying_Type (Result_Subt))
+ and then not Is_Return_Object (Defining_Identifier (Object_Decl))
+ then
Insert_After_And_Analyze (Object_Decl, Ptr_Typ_Decl);
else
Insert_Action (Object_Decl, Ptr_Typ_Decl);
end if;
-- Finally, create an access object initialized to a reference to the
- -- function call.
+ -- function call. We know this access value cannot be null, so mark the
+ -- entity accordingly to suppress the access check.
New_Expr := Make_Reference (Loc, Relocate_Node (Func_Call));
Def_Id := Make_Temporary (Loc, 'R', New_Expr);
Set_Etype (Def_Id, Ref_Type);
+ Set_Is_Known_Non_Null (Def_Id);
Insert_After_And_Analyze (Ptr_Typ_Decl,
Make_Object_Declaration (Loc,
Object_Definition => New_Reference_To (Ref_Type, Loc),
Expression => New_Expr));
- if Is_Constrained (Underlying_Type (Result_Subt)) then
+ -- If the result subtype of the called function is constrained and
+ -- is not itself the return expression of an enclosing BIP function,
+ -- then mark the object as having no initialization.
+
+ if Is_Constrained (Underlying_Type (Result_Subt))
+ and then not Is_Return_Object (Defining_Identifier (Object_Decl))
+ then
Set_Expression (Object_Decl, Empty);
Set_No_Initialization (Object_Decl);
- -- In case of an unconstrained result subtype, rewrite the object
+ -- In case of an unconstrained result subtype, or if the call is the
+ -- return expression of an enclosing BIP function, rewrite the object
-- declaration as an object renaming where the renamed object is a
-- dereference of <function_Call>'reference:
--
is
pragma Assert (Is_Build_In_Place_Function (Func_Id));
Func_Typ : constant Entity_Id := Underlying_Type (Etype (Func_Id));
-
begin
return
not Restriction_Active (No_Finalization)
and then Needs_Finalization (Func_Typ);
end Needs_BIP_Finalization_Master;
+ --------------------------
+ -- Needs_BIP_Alloc_Form --
+ --------------------------
+
+ function Needs_BIP_Alloc_Form (Func_Id : Entity_Id) return Boolean is
+ pragma Assert (Is_Build_In_Place_Function (Func_Id));
+ Func_Typ : constant Entity_Id := Underlying_Type (Etype (Func_Id));
+ begin
+ return not Is_Constrained (Func_Typ) or else Is_Tagged_Type (Func_Typ);
+ end Needs_BIP_Alloc_Form;
+
+ --------------------------------------
+ -- Needs_Result_Accessibility_Level --
+ --------------------------------------
+
+ function Needs_Result_Accessibility_Level
+ (Func_Id : Entity_Id) return Boolean
+ is
+ Func_Typ : constant Entity_Id := Underlying_Type (Etype (Func_Id));
+
+ function Has_Unconstrained_Access_Discriminant_Component
+ (Comp_Typ : Entity_Id) return Boolean;
+ -- Returns True if any component of the type has an unconstrained access
+ -- discriminant.
+
+ -----------------------------------------------------
+ -- Has_Unconstrained_Access_Discriminant_Component --
+ -----------------------------------------------------
+
+ function Has_Unconstrained_Access_Discriminant_Component
+ (Comp_Typ : Entity_Id) return Boolean
+ is
+ begin
+ if not Is_Limited_Type (Comp_Typ) then
+ return False;
+
+ -- Only limited types can have access discriminants with
+ -- defaults.
+
+ elsif Has_Unconstrained_Access_Discriminants (Comp_Typ) then
+ return True;
+
+ elsif Is_Array_Type (Comp_Typ) then
+ return Has_Unconstrained_Access_Discriminant_Component
+ (Underlying_Type (Component_Type (Comp_Typ)));
+
+ elsif Is_Record_Type (Comp_Typ) then
+ declare
+ Comp : Entity_Id;
+
+ begin
+ Comp := First_Component (Comp_Typ);
+ while Present (Comp) loop
+ if Has_Unconstrained_Access_Discriminant_Component
+ (Underlying_Type (Etype (Comp)))
+ then
+ return True;
+ end if;
+
+ Next_Component (Comp);
+ end loop;
+ end;
+ end if;
+
+ return False;
+ end Has_Unconstrained_Access_Discriminant_Component;
+
+ Feature_Disabled : constant Boolean := True;
+ -- Temporary
+
+ -- Start of processing for Needs_Result_Accessibility_Level
+
+ begin
+ -- False if completion unavailable (how does this happen???)
+
+ if not Present (Func_Typ) then
+ return False;
+
+ elsif Feature_Disabled then
+ return False;
+
+ -- False if not a function, also handle enum-lit renames case
+
+ elsif Func_Typ = Standard_Void_Type
+ or else Is_Scalar_Type (Func_Typ)
+ then
+ return False;
+
+ -- Handle a corner case, a cross-dialect subp renaming. For example,
+ -- an Ada 2012 renaming of an Ada 2005 subprogram. This can occur when
+ -- an Ada 2005 (or earlier) unit references predefined run-time units.
+
+ elsif Present (Alias (Func_Id)) then
+
+ -- Unimplemented: a cross-dialect subp renaming which does not set
+ -- the Alias attribute (e.g., a rename of a dereference of an access
+ -- to subprogram value). ???
+
+ return Present (Extra_Accessibility_Of_Result (Alias (Func_Id)));
+
+ -- Remaining cases require Ada 2012 mode
+
+ elsif Ada_Version < Ada_2012 then
+ return False;
+
+ elsif Ekind (Func_Typ) = E_Anonymous_Access_Type
+ or else Is_Tagged_Type (Func_Typ)
+ then
+ -- In the case of, say, a null tagged record result type, the need
+ -- for this extra parameter might not be obvious. This function
+ -- returns True for all tagged types for compatibility reasons.
+ -- A function with, say, a tagged null controlling result type might
+ -- be overridden by a primitive of an extension having an access
+ -- discriminant and the overrider and overridden must have compatible
+ -- calling conventions (including implicitly declared parameters).
+ -- Similarly, values of one access-to-subprogram type might designate
+ -- both a primitive subprogram of a given type and a function
+ -- which is, for example, not a primitive subprogram of any type.
+ -- Again, this requires calling convention compatibility.
+ -- It might be possible to solve these issues by introducing
+ -- wrappers, but that is not the approach that was chosen.
+
+ return True;
+
+ elsif Has_Unconstrained_Access_Discriminants (Func_Typ) then
+ return True;
+
+ elsif Has_Unconstrained_Access_Discriminant_Component (Func_Typ) then
+ return True;
+
+ -- False for all other cases
+
+ else
+ return False;
+ end if;
+ end Needs_Result_Accessibility_Level;
+
end Exp_Ch6;
OSDN Git Service
