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-------------------------------------------------------------------------------
--- --
--- GNAT COMPILER COMPONENTS --
--- --
--- E X P _ C H 6 --
--- --
--- B o d y --
--- --
--- Copyright (C) 1992-2008, Free Software Foundation, Inc. --
--- --
--- GNAT is free software; you can redistribute it and/or modify it under --
--- terms of the GNU General Public License as published by the Free Soft- --
--- ware Foundation; either version 3, or (at your option) any later ver- --
--- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
--- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
--- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
--- for more details. You should have received a copy of the GNU General --
--- Public License distributed with GNAT; see file COPYING3. If not, go to --
--- http://www.gnu.org/licenses for a complete copy of the license. --
--- --
--- GNAT was originally developed by the GNAT team at New York University. --
--- Extensive contributions were provided by Ada Core Technologies Inc. --
--- --
-------------------------------------------------------------------------------
-
-with Atree; use Atree;
-with Checks; use Checks;
-with Debug; use Debug;
-with Einfo; use Einfo;
-with Errout; use Errout;
-with Elists; use Elists;
-with Exp_Atag; use Exp_Atag;
-with Exp_Ch2; use Exp_Ch2;
-with Exp_Ch3; use Exp_Ch3;
-with Exp_Ch7; use Exp_Ch7;
-with Exp_Ch9; use Exp_Ch9;
-with Exp_Dbug; use Exp_Dbug;
-with Exp_Disp; use Exp_Disp;
-with Exp_Dist; use Exp_Dist;
-with Exp_Intr; use Exp_Intr;
-with Exp_Pakd; use Exp_Pakd;
-with Exp_Tss; use Exp_Tss;
-with Exp_Util; use Exp_Util;
-with Exp_VFpt; use Exp_VFpt;
-with Fname; use Fname;
-with Freeze; use Freeze;
-with Inline; use Inline;
-with Lib; use Lib;
-with Namet; use Namet;
-with Nlists; use Nlists;
-with Nmake; use Nmake;
-with Opt; use Opt;
-with Restrict; use Restrict;
-with Rident; use Rident;
-with Rtsfind; use Rtsfind;
-with Sem; use Sem;
-with Sem_Ch6; use Sem_Ch6;
-with Sem_Ch8; use Sem_Ch8;
-with Sem_Ch12; use Sem_Ch12;
-with Sem_Ch13; use Sem_Ch13;
-with Sem_Eval; use Sem_Eval;
-with Sem_Disp; use Sem_Disp;
-with Sem_Dist; use Sem_Dist;
-with Sem_Mech; use Sem_Mech;
-with Sem_Res; use Sem_Res;
-with Sem_Util; use Sem_Util;
-with Sinfo; use Sinfo;
-with Snames; use Snames;
-with Stand; use Stand;
-with Targparm; use Targparm;
-with Tbuild; use Tbuild;
-with Uintp; use Uintp;
-with Validsw; use Validsw;
-
-package body Exp_Ch6 is
-
- -----------------------
- -- Local Subprograms --
- -----------------------
-
- procedure Add_Access_Actual_To_Build_In_Place_Call
- (Function_Call : Node_Id;
- Function_Id : Entity_Id;
- Return_Object : Node_Id;
- Is_Access : Boolean := False);
- -- Ada 2005 (AI-318-02): Apply the Unrestricted_Access attribute to the
- -- object name given by Return_Object and add the attribute to the end of
- -- the actual parameter list associated with the build-in-place function
- -- call denoted by Function_Call. However, if Is_Access is True, then
- -- Return_Object is already an access expression, in which case it's passed
- -- 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
- (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.
-
- procedure Add_Final_List_Actual_To_Build_In_Place_Call
- (Function_Call : Node_Id;
- Function_Id : Entity_Id;
- Acc_Type : Entity_Id;
- Sel_Comp : Node_Id := Empty);
- -- Ada 2005 (AI-318-02): For a build-in-place call, if the result type has
- -- controlled parts, add an actual parameter that is a pointer to
- -- appropriate finalization list. The finalization list is that of the
- -- current scope, except for "new Acc'(F(...))" in which case it's the
- -- finalization list of the access type returned by the allocator. Acc_Type
- -- is that type in the allocator case; Empty otherwise. If Sel_Comp is
- -- not Empty, then it denotes a selected component and the finalization
- -- list is obtained from the _controller list of the prefix object.
-
- procedure Add_Task_Actuals_To_Build_In_Place_Call
- (Function_Call : Node_Id;
- Function_Id : Entity_Id;
- Master_Actual : Node_Id);
- -- Ada 2005 (AI-318-02): For a build-in-place call, if the result type
- -- contains tasks, add two actual parameters: the master, and a pointer to
- -- the caller's activation chain. Master_Actual is the actual parameter
- -- expression to pass for the master. In most cases, this is the current
- -- master (_master). The two exceptions are: If the function call is the
- -- initialization expression for an allocator, we pass the master of the
- -- access type. If the function call is the initialization expression for
- -- a return object, we pass along the master passed in by the caller. The
- -- activation chain to pass is always the local one.
-
- procedure Check_Overriding_Operation (Subp : Entity_Id);
- -- Subp is a dispatching operation. Check whether it may override an
- -- inherited private operation, in which case its DT entry is that of
- -- the hidden operation, not the one it may have received earlier.
- -- This must be done before emitting the code to set the corresponding
- -- DT to the address of the subprogram. The actual placement of Subp in
- -- the proper place in the list of primitive operations is done in
- -- Declare_Inherited_Private_Subprograms, which also has to deal with
- -- implicit operations. This duplication is unavoidable for now???
-
- procedure Detect_Infinite_Recursion (N : Node_Id; Spec : Entity_Id);
- -- This procedure is called only if the subprogram body N, whose spec
- -- has the given entity Spec, contains a parameterless recursive call.
- -- It attempts to generate runtime code to detect if this a case of
- -- infinite recursion.
- --
- -- The body is scanned to determine dependencies. If the only external
- -- dependencies are on a small set of scalar variables, then the values
- -- of these variables are captured on entry to the subprogram, and if
- -- 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_Inlined_Call
- (N : Node_Id;
- Subp : Entity_Id;
- Orig_Subp : Entity_Id);
- -- If called subprogram can be inlined by the front-end, retrieve the
- -- analyzed body, replace formals with actuals and expand call in place.
- -- Generate thunks for actuals that are expressions, and insert the
- -- corresponding constant declarations before the call. If the original
- -- call is to a derived operation, the return type is the one of the
- -- derived operation, but the body is that of the original, so return
- -- expressions in the body must be converted to the desired type (which
- -- is simply not noted in the tree without inline expansion).
-
- function Expand_Protected_Object_Reference
- (N : Node_Id;
- Scop : Entity_Id) return Node_Id;
-
- procedure Expand_Protected_Subprogram_Call
- (N : Node_Id;
- Subp : Entity_Id;
- Scop : Entity_Id);
- -- A call to a protected subprogram within the protected object may appear
- -- as a regular call. The list of actuals must be expanded to contain a
- -- reference to the object itself, and the call becomes a call to the
- -- corresponding protected subprogram.
-
- ----------------------------------------------
- -- Add_Access_Actual_To_Build_In_Place_Call --
- ----------------------------------------------
-
- procedure Add_Access_Actual_To_Build_In_Place_Call
- (Function_Call : Node_Id;
- Function_Id : Entity_Id;
- Return_Object : Node_Id;
- Is_Access : Boolean := False)
- is
- Loc : constant Source_Ptr := Sloc (Function_Call);
- Obj_Address : Node_Id;
- Obj_Acc_Formal : Entity_Id;
-
- begin
- -- Locate the implicit access parameter in the called function
-
- Obj_Acc_Formal := Build_In_Place_Formal (Function_Id, BIP_Object_Access);
-
- -- If no return object is provided, then pass null
-
- if not Present (Return_Object) then
- Obj_Address := Make_Null (Loc);
- Set_Parent (Obj_Address, Function_Call);
-
- -- If Return_Object is already an expression of an access type, then use
- -- it directly, since it must be an access value denoting the return
- -- object, and couldn't possibly be the return object itself.
-
- elsif Is_Access then
- Obj_Address := Return_Object;
- Set_Parent (Obj_Address, Function_Call);
-
- -- Apply Unrestricted_Access to caller's return object
-
- else
- Obj_Address :=
- Make_Attribute_Reference (Loc,
- Prefix => Return_Object,
- Attribute_Name => Name_Unrestricted_Access);
-
- Set_Parent (Return_Object, Obj_Address);
- Set_Parent (Obj_Address, Function_Call);
- end if;
-
- Analyze_And_Resolve (Obj_Address, Etype (Obj_Acc_Formal));
-
- -- 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, Obj_Acc_Formal, Obj_Address);
- end Add_Access_Actual_To_Build_In_Place_Call;
-
- --------------------------------------------------
- -- Add_Alloc_Form_Actual_To_Build_In_Place_Call --
- --------------------------------------------------
-
- procedure Add_Alloc_Form_Actual_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)
- is
- Loc : constant Source_Ptr := Sloc (Function_Call);
- Alloc_Form_Actual : Node_Id;
- Alloc_Form_Formal : Node_Id;
-
- begin
- -- The allocation form generally doesn't need to be passed in the case
- -- of a constrained result subtype, since normally the caller performs
- -- the allocation in that case. However this formal is still needed in
- -- the case where the function has a tagged result, because generally
- -- such functions can be called in a dispatching context and such calls
- -- must be handled like calls to class-wide functions.
-
- if Is_Constrained (Underlying_Type (Etype (Function_Id)))
- and then not Is_Tagged_Type (Underlying_Type (Etype (Function_Id)))
- then
- return;
- end if;
-
- -- Locate the implicit allocation form parameter in the called function.
- -- 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. ???
-
- Alloc_Form_Formal := Build_In_Place_Formal (Function_Id, BIP_Alloc_Form);
-
- if Present (Alloc_Form_Exp) then
- pragma Assert (Alloc_Form = Unspecified);
-
- Alloc_Form_Actual := Alloc_Form_Exp;
-
- else
- pragma Assert (Alloc_Form /= Unspecified);
-
- Alloc_Form_Actual :=
- Make_Integer_Literal (Loc,
- Intval => UI_From_Int (BIP_Allocation_Form'Pos (Alloc_Form)));
- end if;
-
- Analyze_And_Resolve (Alloc_Form_Actual, Etype (Alloc_Form_Formal));
-
- -- 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, Alloc_Form_Formal, Alloc_Form_Actual);
- end Add_Alloc_Form_Actual_To_Build_In_Place_Call;
-
- ------------------------------
- -- Add_Extra_Actual_To_Call --
- ------------------------------
-
- procedure Add_Extra_Actual_To_Call
- (Subprogram_Call : Node_Id;
- Extra_Formal : Entity_Id;
- Extra_Actual : Node_Id)
- is
- Loc : constant Source_Ptr := Sloc (Subprogram_Call);
- Param_Assoc : Node_Id;
-
- begin
- Param_Assoc :=
- Make_Parameter_Association (Loc,
- Selector_Name => New_Occurrence_Of (Extra_Formal, Loc),
- Explicit_Actual_Parameter => Extra_Actual);
-
- Set_Parent (Param_Assoc, Subprogram_Call);
- Set_Parent (Extra_Actual, Param_Assoc);
-
- if Present (Parameter_Associations (Subprogram_Call)) then
- if Nkind (Last (Parameter_Associations (Subprogram_Call))) =
- N_Parameter_Association
- then
-
- -- Find last named actual, and append
-
- declare
- L : Node_Id;
- begin
- L := First_Actual (Subprogram_Call);
- while Present (L) loop
- if No (Next_Actual (L)) then
- Set_Next_Named_Actual (Parent (L), Extra_Actual);
- exit;
- end if;
- Next_Actual (L);
- end loop;
- end;
-
- else
- Set_First_Named_Actual (Subprogram_Call, Extra_Actual);
- end if;
-
- Append (Param_Assoc, To => Parameter_Associations (Subprogram_Call));
-
- else
- Set_Parameter_Associations (Subprogram_Call, New_List (Param_Assoc));
- Set_First_Named_Actual (Subprogram_Call, Extra_Actual);
- end if;
- end Add_Extra_Actual_To_Call;
-
- --------------------------------------------------
- -- Add_Final_List_Actual_To_Build_In_Place_Call --
- --------------------------------------------------
-
- procedure Add_Final_List_Actual_To_Build_In_Place_Call
- (Function_Call : Node_Id;
- Function_Id : Entity_Id;
- Acc_Type : Entity_Id;
- Sel_Comp : Node_Id := Empty)
- is
- Loc : constant Source_Ptr := Sloc (Function_Call);
- Final_List : Node_Id;
- Final_List_Actual : Node_Id;
- Final_List_Formal : Node_Id;
- Is_Ctrl_Result : constant Boolean :=
- Needs_Finalization
- (Underlying_Type (Etype (Function_Id)));
-
- begin
- -- No such extra parameter is needed if there are no controlled parts.
- -- The test for Needs_Finalization accounts for class-wide results
- -- (which potentially have controlled parts, even if the root type
- -- doesn't), and the test for a tagged result type is needed because
- -- calls to such a function can in general occur in dispatching
- -- contexts, which must be treated the same as a call to class-wide
- -- functions. Both of these situations require that a finalization list
- -- be passed.
-
- if not Needs_BIP_Final_List (Function_Id) then
- return;
- end if;
-
- -- Locate implicit finalization list parameter in the called function
-
- Final_List_Formal := Build_In_Place_Formal (Function_Id, BIP_Final_List);
-
- -- Create the actual which is a pointer to the appropriate finalization
- -- list. Acc_Type is present if and only if this call is the
- -- initialization of an allocator. Use the Current_Scope or the Acc_Type
- -- as appropriate.
-
- if Present (Acc_Type)
- and then (Ekind (Acc_Type) = E_Anonymous_Access_Type
- or else
- Present (Associated_Final_Chain (Base_Type (Acc_Type))))
- then
- Final_List := Find_Final_List (Acc_Type);
-
- -- If Sel_Comp is present and the function result is controlled, then
- -- the finalization list will be obtained from the _controller list of
- -- the selected component's prefix object.
-
- elsif Present (Sel_Comp) and then Is_Ctrl_Result then
- Final_List := Find_Final_List (Current_Scope, Sel_Comp);
-
- else
- Final_List := Find_Final_List (Current_Scope);
- end if;
-
- Final_List_Actual :=
- Make_Attribute_Reference (Loc,
- Prefix => Final_List,
- Attribute_Name => Name_Unrestricted_Access);
-
- Analyze_And_Resolve (Final_List_Actual, Etype (Final_List_Formal));
-
- -- 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, Final_List_Formal, Final_List_Actual);
- end Add_Final_List_Actual_To_Build_In_Place_Call;
-
- ---------------------------------------------
- -- Add_Task_Actuals_To_Build_In_Place_Call --
- ---------------------------------------------
-
- procedure Add_Task_Actuals_To_Build_In_Place_Call
- (Function_Call : Node_Id;
- Function_Id : Entity_Id;
- Master_Actual : Node_Id)
- -- Note: Master_Actual can be Empty, but only if there are no tasks
- is
- Loc : constant Source_Ptr := Sloc (Function_Call);
-
- begin
- -- No such extra parameters are needed if there are no tasks
-
- if not Has_Task (Etype (Function_Id)) then
- return;
- end if;
-
- -- The master
-
- declare
- Master_Formal : Node_Id;
- begin
- -- Locate implicit master parameter in the called function
-
- Master_Formal := Build_In_Place_Formal (Function_Id, BIP_Master);
-
- Analyze_And_Resolve (Master_Actual, Etype (Master_Formal));
-
- -- 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, Master_Formal, Master_Actual);
- end;
-
- -- The activation chain
-
- declare
- Activation_Chain_Actual : Node_Id;
- Activation_Chain_Formal : Node_Id;
- begin
- -- Locate implicit activation chain parameter in the called function
-
- Activation_Chain_Formal := Build_In_Place_Formal
- (Function_Id, BIP_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);
-
- Analyze_And_Resolve
- (Activation_Chain_Actual, Etype (Activation_Chain_Formal));
-
- -- 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;
- end Add_Task_Actuals_To_Build_In_Place_Call;
-
- -----------------------
- -- BIP_Formal_Suffix --
- -----------------------
-
- function BIP_Formal_Suffix (Kind : BIP_Formal_Kind) return String is
- begin
- case Kind is
- when BIP_Alloc_Form =>
- return "BIPalloc";
- when BIP_Final_List =>
- return "BIPfinallist";
- when BIP_Master =>
- return "BIPmaster";
- when BIP_Activation_Chain =>
- return "BIPactivationchain";
- when BIP_Object_Access =>
- return "BIPaccess";
- end case;
- end BIP_Formal_Suffix;
-
- ---------------------------
- -- Build_In_Place_Formal --
- ---------------------------
-
- function Build_In_Place_Formal
- (Func : Entity_Id;
- Kind : BIP_Formal_Kind) return Entity_Id
- is
- 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. ???
-
- loop
- pragma Assert (Present (Extra_Formal));
- exit when
- Chars (Extra_Formal) =
- New_External_Name (Chars (Func), BIP_Formal_Suffix (Kind));
- Next_Formal_With_Extras (Extra_Formal);
- end loop;
-
- return Extra_Formal;
- end Build_In_Place_Formal;
-
- --------------------------------
- -- Check_Overriding_Operation --
- --------------------------------
-
- procedure Check_Overriding_Operation (Subp : Entity_Id) is
- Typ : constant Entity_Id := Find_Dispatching_Type (Subp);
- Op_List : constant Elist_Id := Primitive_Operations (Typ);
- Op_Elmt : Elmt_Id;
- Prim_Op : Entity_Id;
- Par_Op : Entity_Id;
-
- begin
- if Is_Derived_Type (Typ)
- and then not Is_Private_Type (Typ)
- and then In_Open_Scopes (Scope (Etype (Typ)))
- and then Typ = Base_Type (Typ)
- then
- -- Subp overrides an inherited private operation if there is an
- -- inherited operation with a different name than Subp (see
- -- Derive_Subprogram) whose Alias is a hidden subprogram with the
- -- same name as Subp.
-
- Op_Elmt := First_Elmt (Op_List);
- while Present (Op_Elmt) loop
- Prim_Op := Node (Op_Elmt);
- Par_Op := Alias (Prim_Op);
-
- if Present (Par_Op)
- and then not Comes_From_Source (Prim_Op)
- and then Chars (Prim_Op) /= Chars (Par_Op)
- and then Chars (Par_Op) = Chars (Subp)
- and then Is_Hidden (Par_Op)
- and then Type_Conformant (Prim_Op, Subp)
- then
- Set_DT_Position (Subp, DT_Position (Prim_Op));
- end if;
-
- Next_Elmt (Op_Elmt);
- end loop;
- end if;
- end Check_Overriding_Operation;
-
- -------------------------------
- -- Detect_Infinite_Recursion --
- -------------------------------
-
- procedure Detect_Infinite_Recursion (N : Node_Id; Spec : Entity_Id) is
- Loc : constant Source_Ptr := Sloc (N);
-
- Var_List : constant Elist_Id := New_Elmt_List;
- -- List of globals referenced by body of procedure
-
- Call_List : constant Elist_Id := New_Elmt_List;
- -- List of recursive calls in body of procedure
-
- Shad_List : constant Elist_Id := New_Elmt_List;
- -- List of entity id's for entities created to capture the value of
- -- referenced globals on entry to the procedure.
-
- Scop : constant Uint := Scope_Depth (Spec);
- -- This is used to record the scope depth of the current procedure, so
- -- that we can identify global references.
-
- Max_Vars : constant := 4;
- -- Do not test more than four global variables
-
- Count_Vars : Natural := 0;
- -- Count variables found so far
-
- Var : Entity_Id;
- Elm : Elmt_Id;
- Ent : Entity_Id;
- Call : Elmt_Id;
- Decl : Node_Id;
- Test : Node_Id;
- Elm1 : Elmt_Id;
- Elm2 : Elmt_Id;
- Last : Node_Id;
-
- function Process (Nod : Node_Id) return Traverse_Result;
- -- Function to traverse the subprogram body (using Traverse_Func)
-
- -------------
- -- Process --
- -------------
-
- function Process (Nod : Node_Id) return Traverse_Result is
- begin
- -- Procedure call
-
- if Nkind (Nod) = N_Procedure_Call_Statement then
-
- -- Case of one of the detected recursive calls
-
- if Is_Entity_Name (Name (Nod))
- and then Has_Recursive_Call (Entity (Name (Nod)))
- and then Entity (Name (Nod)) = Spec
- then
- Append_Elmt (Nod, Call_List);
- return Skip;
-
- -- Any other procedure call may have side effects
-
- else
- return Abandon;
- end if;
-
- -- A call to a pure function can always be ignored
-
- elsif Nkind (Nod) = N_Function_Call
- and then Is_Entity_Name (Name (Nod))
- and then Is_Pure (Entity (Name (Nod)))
- then
- return Skip;
-
- -- Case of an identifier reference
-
- elsif Nkind (Nod) = N_Identifier then
- Ent := Entity (Nod);
-
- -- If no entity, then ignore the reference
-
- -- Not clear why this can happen. To investigate, remove this
- -- test and look at the crash that occurs here in 3401-004 ???
-
- if No (Ent) then
- return Skip;
-
- -- Ignore entities with no Scope, again not clear how this
- -- can happen, to investigate, look at 4108-008 ???
-
- elsif No (Scope (Ent)) then
- return Skip;
-
- -- Ignore the reference if not to a more global object
-
- elsif Scope_Depth (Scope (Ent)) >= Scop then
- return Skip;
-
- -- References to types, exceptions and constants are always OK
-
- elsif Is_Type (Ent)
- or else Ekind (Ent) = E_Exception
- or else Ekind (Ent) = E_Constant
- then
- return Skip;
-
- -- If other than a non-volatile scalar variable, we have some
- -- kind of global reference (e.g. to a function) that we cannot
- -- deal with so we forget the attempt.
-
- elsif Ekind (Ent) /= E_Variable
- or else not Is_Scalar_Type (Etype (Ent))
- or else Treat_As_Volatile (Ent)
- then
- return Abandon;
-
- -- Otherwise we have a reference to a global scalar
-
- else
- -- Loop through global entities already detected
-
- Elm := First_Elmt (Var_List);
- loop
- -- If not detected before, record this new global reference
-
- if No (Elm) then
- Count_Vars := Count_Vars + 1;
-
- if Count_Vars <= Max_Vars then
- Append_Elmt (Entity (Nod), Var_List);
- else
- return Abandon;
- end if;
-
- exit;
-
- -- If recorded before, ignore
-
- elsif Node (Elm) = Entity (Nod) then
- return Skip;
-
- -- Otherwise keep looking
-
- else
- Next_Elmt (Elm);
- end if;
- end loop;
-
- return Skip;
- end if;
-
- -- For all other node kinds, recursively visit syntactic children
-
- else
- return OK;
- end if;
- end Process;
-
- function Traverse_Body is new Traverse_Func (Process);
-
- -- Start of processing for Detect_Infinite_Recursion
-
- begin
- -- Do not attempt detection in No_Implicit_Conditional mode, since we
- -- won't be able to generate the code to handle the recursion in any
- -- case.
-
- if Restriction_Active (No_Implicit_Conditionals) then
- return;
- end if;
-
- -- Otherwise do traversal and quit if we get abandon signal
-
- if Traverse_Body (N) = Abandon then
- return;
-
- -- We must have a call, since Has_Recursive_Call was set. If not just
- -- ignore (this is only an error check, so if we have a funny situation,
- -- due to bugs or errors, we do not want to bomb!)
-
- elsif Is_Empty_Elmt_List (Call_List) then
- return;
- end if;
-
- -- Here is the case where we detect recursion at compile time
-
- -- Push our current scope for analyzing the declarations and code that
- -- we will insert for the checking.
-
- Push_Scope (Spec);
-
- -- This loop builds temporary variables for each of the referenced
- -- globals, so that at the end of the loop the list Shad_List contains
- -- these temporaries in one-to-one correspondence with the elements in
- -- Var_List.
-
- Last := Empty;
- Elm := First_Elmt (Var_List);
- while Present (Elm) loop
- Var := Node (Elm);
- Ent :=
- Make_Defining_Identifier (Loc,
- Chars => New_Internal_Name ('S'));
- Append_Elmt (Ent, Shad_List);
-
- -- Insert a declaration for this temporary at the start of the
- -- declarations for the procedure. The temporaries are declared as
- -- constant objects initialized to the current values of the
- -- corresponding temporaries.
-
- Decl :=
- Make_Object_Declaration (Loc,
- Defining_Identifier => Ent,
- Object_Definition => New_Occurrence_Of (Etype (Var), Loc),
- Constant_Present => True,
- Expression => New_Occurrence_Of (Var, Loc));
-
- if No (Last) then
- Prepend (Decl, Declarations (N));
- else
- Insert_After (Last, Decl);
- end if;
-
- Last := Decl;
- Analyze (Decl);
- Next_Elmt (Elm);
- end loop;
-
- -- Loop through calls
-
- Call := First_Elmt (Call_List);
- while Present (Call) loop
-
- -- Build a predicate expression of the form
-
- -- True
- -- and then global1 = temp1
- -- and then global2 = temp2
- -- ...
-
- -- This predicate determines if any of the global values
- -- referenced by the procedure have changed since the
- -- current call, if not an infinite recursion is assured.
-
- Test := New_Occurrence_Of (Standard_True, Loc);
-
- Elm1 := First_Elmt (Var_List);
- Elm2 := First_Elmt (Shad_List);
- while Present (Elm1) loop
- Test :=
- Make_And_Then (Loc,
- Left_Opnd => Test,
- Right_Opnd =>
- Make_Op_Eq (Loc,
- Left_Opnd => New_Occurrence_Of (Node (Elm1), Loc),
- Right_Opnd => New_Occurrence_Of (Node (Elm2), Loc)));
-
- Next_Elmt (Elm1);
- Next_Elmt (Elm2);
- end loop;
-
- -- Now we replace the call with the sequence
-
- -- if no-changes (see above) then
- -- raise Storage_Error;
- -- else
- -- original-call
- -- end if;
-
- Rewrite (Node (Call),
- Make_If_Statement (Loc,
- Condition => Test,
- Then_Statements => New_List (
- Make_Raise_Storage_Error (Loc,
- Reason => SE_Infinite_Recursion)),
-
- Else_Statements => New_List (
- Relocate_Node (Node (Call)))));
-
- Analyze (Node (Call));
-
- Next_Elmt (Call);
- end loop;
-
- -- Remove temporary scope stack entry used for analysis
-
- Pop_Scope;
- end Detect_Infinite_Recursion;
-
- --------------------
- -- Expand_Actuals --
- --------------------
-
- procedure Expand_Actuals (N : Node_Id; Subp : Entity_Id) is
- Loc : constant Source_Ptr := Sloc (N);
- Actual : Node_Id;
- Formal : Entity_Id;
- N_Node : Node_Id;
- Post_Call : List_Id;
- E_Formal : Entity_Id;
-
- procedure Add_Call_By_Copy_Code;
- -- For cases where the parameter must be passed by copy, this routine
- -- generates a temporary variable into which the actual is copied and
- -- then passes this as the parameter. For an OUT or IN OUT parameter,
- -- an assignment is also generated to copy the result back. The call
- -- also takes care of any constraint checks required for the type
- -- conversion case (on both the way in and the way out).
-
- procedure Add_Simple_Call_By_Copy_Code;
- -- This is similar to the above, but is used in cases where we know
- -- that all that is needed is to simply create a temporary and copy
- -- the value in and out of the temporary.
-
- procedure Check_Fortran_Logical;
- -- A value of type Logical that is passed through a formal parameter
- -- must be normalized because .TRUE. usually does not have the same
- -- representation as True. We assume that .FALSE. = False = 0.
- -- What about functions that return a logical type ???
-
- function Is_Legal_Copy return Boolean;
- -- Check that an actual can be copied before generating the temporary
- -- to be used in the call. If the actual is of a by_reference type then
- -- the program is illegal (this can only happen in the presence of
- -- rep. clauses that force an incorrect alignment). If the formal is
- -- a by_reference parameter imposed by a DEC pragma, emit a warning to
- -- the effect that this might lead to unaligned arguments.
-
- function Make_Var (Actual : Node_Id) return Entity_Id;
- -- Returns an entity that refers to the given actual parameter,
- -- Actual (not including any type conversion). If Actual is an
- -- entity name, then this entity is returned unchanged, otherwise
- -- a renaming is created to provide an entity for the actual.
-
- procedure Reset_Packed_Prefix;
- -- The expansion of a packed array component reference is delayed in
- -- the context of a call. Now we need to complete the expansion, so we
- -- unmark the analyzed bits in all prefixes.
-
- ---------------------------
- -- Add_Call_By_Copy_Code --
- ---------------------------
-
- procedure Add_Call_By_Copy_Code is
- Expr : Node_Id;
- Init : Node_Id;
- Temp : Entity_Id;
- Indic : Node_Id;
- Var : Entity_Id;
- F_Typ : constant Entity_Id := Etype (Formal);
- V_Typ : Entity_Id;
- Crep : Boolean;
-
- begin
- if not Is_Legal_Copy then
- return;
- end if;
-
- Temp :=
- Make_Defining_Identifier (Loc,
- Chars => New_Internal_Name ('T'));
-
- -- Use formal type for temp, unless formal type is an unconstrained
- -- array, in which case we don't have to worry about bounds checks,
- -- and we use the actual type, since that has appropriate bounds.
-
- if Is_Array_Type (F_Typ) and then not Is_Constrained (F_Typ) then
- Indic := New_Occurrence_Of (Etype (Actual), Loc);
- else
- Indic := New_Occurrence_Of (Etype (Formal), Loc);
- end if;
-
- if Nkind (Actual) = N_Type_Conversion then
- V_Typ := Etype (Expression (Actual));
-
- -- If the formal is an (in-)out parameter, capture the name
- -- of the variable in order to build the post-call assignment.
-
- Var := Make_Var (Expression (Actual));
-
- Crep := not Same_Representation
- (F_Typ, Etype (Expression (Actual)));
-
- else
- V_Typ := Etype (Actual);
- Var := Make_Var (Actual);
- Crep := False;
- end if;
-
- -- Setup initialization for case of in out parameter, or an out
- -- parameter where the formal is an unconstrained array (in the
- -- latter case, we have to pass in an object with bounds).
-
- -- If this is an out parameter, the initial copy is wasteful, so as
- -- an optimization for the one-dimensional case we extract the
- -- bounds of the actual and build an uninitialized temporary of the
- -- right size.
-
- if Ekind (Formal) = E_In_Out_Parameter
- or else (Is_Array_Type (F_Typ) and then not Is_Constrained (F_Typ))
- then
- if Nkind (Actual) = N_Type_Conversion then
- if Conversion_OK (Actual) then
- Init := OK_Convert_To (F_Typ, New_Occurrence_Of (Var, Loc));
- else
- Init := Convert_To (F_Typ, New_Occurrence_Of (Var, Loc));
- end if;
-
- elsif Ekind (Formal) = E_Out_Parameter
- and then Is_Array_Type (F_Typ)
- and then Number_Dimensions (F_Typ) = 1
- and then not Has_Non_Null_Base_Init_Proc (F_Typ)
- then
- -- Actual is a one-dimensional array or slice, and the type
- -- requires no initialization. Create a temporary of the
- -- right size, but do not copy actual into it (optimization).
-
- Init := Empty;
- Indic :=
- Make_Subtype_Indication (Loc,
- Subtype_Mark =>
- New_Occurrence_Of (F_Typ, Loc),
- Constraint =>
- Make_Index_Or_Discriminant_Constraint (Loc,
- Constraints => New_List (
- Make_Range (Loc,
- Low_Bound =>
- Make_Attribute_Reference (Loc,
- Prefix => New_Occurrence_Of (Var, Loc),
- Attribute_Name => Name_First),
- High_Bound =>
- Make_Attribute_Reference (Loc,
- Prefix => New_Occurrence_Of (Var, Loc),
- Attribute_Name => Name_Last)))));
-
- else
- Init := New_Occurrence_Of (Var, Loc);
- end if;
-
- -- An initialization is created for packed conversions as
- -- actuals for out parameters to enable Make_Object_Declaration
- -- to determine the proper subtype for N_Node. Note that this
- -- is wasteful because the extra copying on the call side is
- -- not required for such out parameters. ???
-
- elsif Ekind (Formal) = E_Out_Parameter
- and then Nkind (Actual) = N_Type_Conversion
- and then (Is_Bit_Packed_Array (F_Typ)
- or else
- Is_Bit_Packed_Array (Etype (Expression (Actual))))
- then
- if Conversion_OK (Actual) then
- Init := OK_Convert_To (F_Typ, New_Occurrence_Of (Var, Loc));
- else
- Init := Convert_To (F_Typ, New_Occurrence_Of (Var, Loc));
- end if;
-
- elsif Ekind (Formal) = E_In_Parameter then
-
- -- Handle the case in which the actual is a type conversion
-
- if Nkind (Actual) = N_Type_Conversion then
- if Conversion_OK (Actual) then
- Init := OK_Convert_To (F_Typ, New_Occurrence_Of (Var, Loc));
- else
- Init := Convert_To (F_Typ, New_Occurrence_Of (Var, Loc));
- end if;
- else
- Init := New_Occurrence_Of (Var, Loc);
- end if;
-
- else
- Init := Empty;
- end if;
-
- N_Node :=
- Make_Object_Declaration (Loc,
- Defining_Identifier => Temp,
- Object_Definition => Indic,
- Expression => Init);
- Set_Assignment_OK (N_Node);
- Insert_Action (N, N_Node);
-
- -- Now, normally the deal here is that we use the defining
- -- identifier created by that object declaration. There is
- -- one exception to this. In the change of representation case
- -- the above declaration will end up looking like:
-
- -- temp : type := identifier;
-
- -- And in this case we might as well use the identifier directly
- -- and eliminate the temporary. Note that the analysis of the
- -- declaration was not a waste of time in that case, since it is
- -- what generated the necessary change of representation code. If
- -- the change of representation introduced additional code, as in
- -- a fixed-integer conversion, the expression is not an identifier
- -- and must be kept.
-
- if Crep
- and then Present (Expression (N_Node))
- and then Is_Entity_Name (Expression (N_Node))
- then
- Temp := Entity (Expression (N_Node));
- Rewrite (N_Node, Make_Null_Statement (Loc));
- end if;
-
- -- For IN parameter, all we do is to replace the actual
-
- if Ekind (Formal) = E_In_Parameter then
- Rewrite (Actual, New_Reference_To (Temp, Loc));
- Analyze (Actual);
-
- -- Processing for OUT or IN OUT parameter
-
- else
- -- Kill current value indications for the temporary variable we
- -- created, since we just passed it as an OUT parameter.
-
- Kill_Current_Values (Temp);
-
- -- If type conversion, use reverse conversion on exit
-
- if Nkind (Actual) = N_Type_Conversion then
- if Conversion_OK (Actual) then
- Expr := OK_Convert_To (V_Typ, New_Occurrence_Of (Temp, Loc));
- else
- Expr := Convert_To (V_Typ, New_Occurrence_Of (Temp, Loc));
- end if;
- else
- Expr := New_Occurrence_Of (Temp, Loc);
- end if;
-
- Rewrite (Actual, New_Reference_To (Temp, Loc));
- Analyze (Actual);
-
- -- If the actual is a conversion of a packed reference, it may
- -- already have been expanded by Remove_Side_Effects, and the
- -- resulting variable is a temporary which does not designate
- -- the proper out-parameter, which may not be addressable. In
- -- that case, generate an assignment to the original expression
- -- (before expansion of the packed reference) so that the proper
- -- expansion of assignment to a packed component can take place.
-
- declare
- Obj : Node_Id;
- Lhs : Node_Id;
-
- begin
- if Is_Renaming_Of_Object (Var)
- and then Nkind (Renamed_Object (Var)) = N_Selected_Component
- and then Is_Entity_Name (Prefix (Renamed_Object (Var)))
- and then Nkind (Original_Node (Prefix (Renamed_Object (Var))))
- = N_Indexed_Component
- and then
- Has_Non_Standard_Rep (Etype (Prefix (Renamed_Object (Var))))
- then
- Obj := Renamed_Object (Var);
- Lhs :=
- Make_Selected_Component (Loc,
- Prefix =>
- New_Copy_Tree (Original_Node (Prefix (Obj))),
- Selector_Name => New_Copy (Selector_Name (Obj)));
- Reset_Analyzed_Flags (Lhs);
-
- else
- Lhs := New_Occurrence_Of (Var, Loc);
- end if;
-
- Set_Assignment_OK (Lhs);
-
- Append_To (Post_Call,
- Make_Assignment_Statement (Loc,
- Name => Lhs,
- Expression => Expr));
- end;
- end if;
-
- end Add_Call_By_Copy_Code;
-
- ----------------------------------
- -- Add_Simple_Call_By_Copy_Code --
- ----------------------------------
-
- procedure Add_Simple_Call_By_Copy_Code is
- Temp : Entity_Id;
- Decl : Node_Id;
- Incod : Node_Id;
- Outcod : Node_Id;
- Lhs : Node_Id;
- Rhs : Node_Id;
- Indic : Node_Id;
- F_Typ : constant Entity_Id := Etype (Formal);
-
- begin
- if not Is_Legal_Copy then
- return;
- end if;
-
- -- Use formal type for temp, unless formal type is an unconstrained
- -- array, in which case we don't have to worry about bounds checks,
- -- and we use the actual type, since that has appropriate bounds.
-
- if Is_Array_Type (F_Typ) and then not Is_Constrained (F_Typ) then
- Indic := New_Occurrence_Of (Etype (Actual), Loc);
- else
- Indic := New_Occurrence_Of (Etype (Formal), Loc);
- end if;
-
- -- Prepare to generate code
-
- Reset_Packed_Prefix;
-
- Temp :=
- Make_Defining_Identifier (Loc,
- Chars => New_Internal_Name ('T'));
- Incod := Relocate_Node (Actual);
- Outcod := New_Copy_Tree (Incod);
-
- -- Generate declaration of temporary variable, initializing it
- -- with the input parameter unless we have an OUT formal or
- -- this is an initialization call.
-
- -- If the formal is an out parameter with discriminants, the
- -- discriminants must be captured even if the rest of the object
- -- is in principle uninitialized, because the discriminants may
- -- be read by the called subprogram.
-
- if Ekind (Formal) = E_Out_Parameter then
- Incod := Empty;
-
- if Has_Discriminants (Etype (Formal)) then
- Indic := New_Occurrence_Of (Etype (Actual), Loc);
- end if;
-
- elsif Inside_Init_Proc then
-
- -- Could use a comment here to match comment below ???
-
- if Nkind (Actual) /= N_Selected_Component
- or else
- not Has_Discriminant_Dependent_Constraint
- (Entity (Selector_Name (Actual)))
- then
- Incod := Empty;
-
- -- Otherwise, keep the component in order to generate the proper
- -- actual subtype, that depends on enclosing discriminants.
-
- else
- null;
- end if;
- end if;
-
- Decl :=
- Make_Object_Declaration (Loc,
- Defining_Identifier => Temp,
- Object_Definition => Indic,
- Expression => Incod);
-
- if Inside_Init_Proc
- and then No (Incod)
- then
- -- If the call is to initialize a component of a composite type,
- -- and the component does not depend on discriminants, use the
- -- actual type of the component. This is required in case the
- -- component is constrained, because in general the formal of the
- -- initialization procedure will be unconstrained. Note that if
- -- the component being initialized is constrained by an enclosing
- -- discriminant, the presence of the initialization in the
- -- declaration will generate an expression for the actual subtype.
-
- Set_No_Initialization (Decl);
- Set_Object_Definition (Decl,
- New_Occurrence_Of (Etype (Actual), Loc));
- end if;
-
- Insert_Action (N, Decl);
-
- -- The actual is simply a reference to the temporary
-
- Rewrite (Actual, New_Occurrence_Of (Temp, Loc));
-
- -- Generate copy out if OUT or IN OUT parameter
-
- if Ekind (Formal) /= E_In_Parameter then
- Lhs := Outcod;
- Rhs := New_Occurrence_Of (Temp, Loc);
-
- -- Deal with conversion
-
- if Nkind (Lhs) = N_Type_Conversion then
- Lhs := Expression (Lhs);
- Rhs := Convert_To (Etype (Actual), Rhs);
- end if;
-
- Append_To (Post_Call,
- Make_Assignment_Statement (Loc,
- Name => Lhs,
- Expression => Rhs));
- Set_Assignment_OK (Name (Last (Post_Call)));
- end if;
- end Add_Simple_Call_By_Copy_Code;
-
- ---------------------------
- -- Check_Fortran_Logical --
- ---------------------------
-
- procedure Check_Fortran_Logical is
- Logical : constant Entity_Id := Etype (Formal);
- Var : Entity_Id;
-
- -- Note: this is very incomplete, e.g. it does not handle arrays
- -- of logical values. This is really not the right approach at all???)
-
- begin
- if Convention (Subp) = Convention_Fortran
- and then Root_Type (Etype (Formal)) = Standard_Boolean
- and then Ekind (Formal) /= E_In_Parameter
- then
- Var := Make_Var (Actual);
- Append_To (Post_Call,
- Make_Assignment_Statement (Loc,
- Name => New_Occurrence_Of (Var, Loc),
- Expression =>
- Unchecked_Convert_To (
- Logical,
- Make_Op_Ne (Loc,
- Left_Opnd => New_Occurrence_Of (Var, Loc),
- Right_Opnd =>
- Unchecked_Convert_To (
- Logical,
- New_Occurrence_Of (Standard_False, Loc))))));
- end if;
- end Check_Fortran_Logical;
-
- -------------------
- -- Is_Legal_Copy --
- -------------------
-
- function Is_Legal_Copy return Boolean is
- begin
- -- An attempt to copy a value of such a type can only occur if
- -- representation clauses give the actual a misaligned address.
-
- if Is_By_Reference_Type (Etype (Formal)) then
- Error_Msg_N
- ("misaligned actual cannot be passed by reference", Actual);
- return False;
-
- -- For users of Starlet, we assume that the specification of by-
- -- reference mechanism is mandatory. This may lead to unaligned
- -- objects but at least for DEC legacy code it is known to work.
- -- The warning will alert users of this code that a problem may
- -- be lurking.
-
- elsif Mechanism (Formal) = By_Reference
- and then Is_Valued_Procedure (Scope (Formal))
- then
- Error_Msg_N
- ("by_reference actual may be misaligned?", Actual);
- return False;
-
- else
- return True;
- end if;
- end Is_Legal_Copy;
-
- --------------
- -- Make_Var --
- --------------
-
- function Make_Var (Actual : Node_Id) return Entity_Id is
- Var : Entity_Id;
-
- begin
- if Is_Entity_Name (Actual) then
- return Entity (Actual);
-
- else
- Var :=
- Make_Defining_Identifier (Loc,
- Chars => New_Internal_Name ('T'));
-
- N_Node :=
- Make_Object_Renaming_Declaration (Loc,
- Defining_Identifier => Var,
- Subtype_Mark =>
- New_Occurrence_Of (Etype (Actual), Loc),
- Name => Relocate_Node (Actual));
-
- Insert_Action (N, N_Node);
- return Var;
- end if;
- end Make_Var;
-
- -------------------------
- -- Reset_Packed_Prefix --
- -------------------------
-
- procedure Reset_Packed_Prefix is
- Pfx : Node_Id := Actual;
- begin
- loop
- Set_Analyzed (Pfx, False);
- exit when
- not Nkind_In (Pfx, N_Selected_Component, N_Indexed_Component);
- Pfx := Prefix (Pfx);
- end loop;
- end Reset_Packed_Prefix;
-
- -- Start of processing for Expand_Actuals
-
- begin
- Post_Call := New_List;
-
- Formal := First_Formal (Subp);
- Actual := First_Actual (N);
- while Present (Formal) loop
- E_Formal := Etype (Formal);
-
- if Is_Scalar_Type (E_Formal)
- or else Nkind (Actual) = N_Slice
- then
- Check_Fortran_Logical;
-
- -- RM 6.4.1 (11)
-
- elsif Ekind (Formal) /= E_Out_Parameter then
-
- -- The unusual case of the current instance of a protected type
- -- requires special handling. This can only occur in the context
- -- of a call within the body of a protected operation.
-
- if Is_Entity_Name (Actual)
- and then Ekind (Entity (Actual)) = E_Protected_Type
- and then In_Open_Scopes (Entity (Actual))
- then
- if Scope (Subp) /= Entity (Actual) then
- Error_Msg_N ("operation outside protected type may not "
- & "call back its protected operations?", Actual);
- end if;
-
- Rewrite (Actual,
- Expand_Protected_Object_Reference (N, Entity (Actual)));
- end if;
-
- -- Ada 2005 (AI-318-02): If the actual parameter is a call to a
- -- build-in-place function, then a temporary return object needs
- -- to be created and access to it must be passed to the function.
- -- Currently we limit such functions to those with inherently
- -- limited result subtypes, but eventually we plan to expand the
- -- functions that are treated as build-in-place to include other
- -- composite result types.
-
- if Ada_Version >= Ada_05
- and then Is_Build_In_Place_Function_Call (Actual)
- then
- Make_Build_In_Place_Call_In_Anonymous_Context (Actual);
- end if;
-
- Apply_Constraint_Check (Actual, E_Formal);
-
- -- Out parameter case. No constraint checks on access type
- -- RM 6.4.1 (13)
-
- elsif Is_Access_Type (E_Formal) then
- null;
-
- -- RM 6.4.1 (14)
-
- elsif Has_Discriminants (Base_Type (E_Formal))
- or else Has_Non_Null_Base_Init_Proc (E_Formal)
- then
- Apply_Constraint_Check (Actual, E_Formal);
-
- -- RM 6.4.1 (15)
-
- else
- Apply_Constraint_Check (Actual, Base_Type (E_Formal));
- end if;
-
- -- Processing for IN-OUT and OUT parameters
-
- if Ekind (Formal) /= E_In_Parameter then
-
- -- For type conversions of arrays, apply length/range checks
-
- if Is_Array_Type (E_Formal)
- and then Nkind (Actual) = N_Type_Conversion
- then
- if Is_Constrained (E_Formal) then
- Apply_Length_Check (Expression (Actual), E_Formal);
- else
- Apply_Range_Check (Expression (Actual), E_Formal);
- end if;
- end if;
-
- -- If argument is a type conversion for a type that is passed
- -- by copy, then we must pass the parameter by copy.
-
- if Nkind (Actual) = N_Type_Conversion
- and then
- (Is_Numeric_Type (E_Formal)
- or else Is_Access_Type (E_Formal)
- or else Is_Enumeration_Type (E_Formal)
- or else Is_Bit_Packed_Array (Etype (Formal))
- or else Is_Bit_Packed_Array (Etype (Expression (Actual)))
-
- -- Also pass by copy if change of representation
-
- or else not Same_Representation
- (Etype (Formal),
- Etype (Expression (Actual))))
- then
- Add_Call_By_Copy_Code;
-
- -- References to components of bit packed arrays are expanded
- -- at this point, rather than at the point of analysis of the
- -- actuals, to handle the expansion of the assignment to
- -- [in] out parameters.
-
- elsif Is_Ref_To_Bit_Packed_Array (Actual) then
- Add_Simple_Call_By_Copy_Code;
-
- -- If a non-scalar actual is possibly bit-aligned, we need a copy
- -- because the back-end cannot cope with such objects. In other
- -- cases where alignment forces a copy, the back-end generates
- -- it properly. It should not be generated unconditionally in the
- -- front-end because it does not know precisely the alignment
- -- requirements of the target, and makes too conservative an
- -- estimate, leading to superfluous copies or spurious errors
- -- on by-reference parameters.
-
- elsif Nkind (Actual) = N_Selected_Component
- and then
- Component_May_Be_Bit_Aligned (Entity (Selector_Name (Actual)))
- and then not Represented_As_Scalar (Etype (Formal))
- then
- Add_Simple_Call_By_Copy_Code;
-
- -- References to slices of bit packed arrays are expanded
-
- elsif Is_Ref_To_Bit_Packed_Slice (Actual) then
- Add_Call_By_Copy_Code;
-
- -- References to possibly unaligned slices of arrays are expanded
-
- elsif Is_Possibly_Unaligned_Slice (Actual) then
- Add_Call_By_Copy_Code;
-
- -- Deal with access types where the actual subtype and the
- -- formal subtype are not the same, requiring a check.
-
- -- It is necessary to exclude tagged types because of "downward
- -- conversion" errors.
-
- elsif Is_Access_Type (E_Formal)
- and then not Same_Type (E_Formal, Etype (Actual))
- and then not Is_Tagged_Type (Designated_Type (E_Formal))
- then
- Add_Call_By_Copy_Code;
-
- -- If the actual is not a scalar and is marked for volatile
- -- treatment, whereas the formal is not volatile, then pass
- -- by copy unless it is a by-reference type.
-
- elsif Is_Entity_Name (Actual)
- and then Treat_As_Volatile (Entity (Actual))
- and then not Is_By_Reference_Type (Etype (Actual))
- and then not Is_Scalar_Type (Etype (Entity (Actual)))
- and then not Treat_As_Volatile (E_Formal)
- then
- Add_Call_By_Copy_Code;
-
- elsif Nkind (Actual) = N_Indexed_Component
- and then Is_Entity_Name (Prefix (Actual))
- and then Has_Volatile_Components (Entity (Prefix (Actual)))
- then
- Add_Call_By_Copy_Code;
- end if;
-
- -- Processing for IN parameters
-
- else
- -- For IN parameters is in the packed array case, we expand an
- -- indexed component (the circuit in Exp_Ch4 deliberately left
- -- indexed components appearing as actuals untouched, so that
- -- the special processing above for the OUT and IN OUT cases
- -- could be performed. We could make the test in Exp_Ch4 more
- -- complex and have it detect the parameter mode, but it is
- -- easier simply to handle all cases here.)
-
- if Nkind (Actual) = N_Indexed_Component
- and then Is_Packed (Etype (Prefix (Actual)))
- then
- Reset_Packed_Prefix;
- Expand_Packed_Element_Reference (Actual);
-
- -- If we have a reference to a bit packed array, we copy it,
- -- since the actual must be byte aligned.
-
- -- Is this really necessary in all cases???
-
- elsif Is_Ref_To_Bit_Packed_Array (Actual) then
- Add_Simple_Call_By_Copy_Code;
-
- -- If a non-scalar actual is possibly unaligned, we need a copy
-
- elsif Is_Possibly_Unaligned_Object (Actual)
- and then not Represented_As_Scalar (Etype (Formal))
- then
- Add_Simple_Call_By_Copy_Code;
-
- -- Similarly, we have to expand slices of packed arrays here
- -- because the result must be byte aligned.
-
- elsif Is_Ref_To_Bit_Packed_Slice (Actual) then
- Add_Call_By_Copy_Code;
-
- -- Only processing remaining is to pass by copy if this is a
- -- reference to a possibly unaligned slice, since the caller
- -- expects an appropriately aligned argument.
-
- elsif Is_Possibly_Unaligned_Slice (Actual) then
- Add_Call_By_Copy_Code;
- end if;
- end if;
-
- Next_Formal (Formal);
- Next_Actual (Actual);
- end loop;
-
- -- Find right place to put post call stuff if it is present
-
- 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.
-
- if not Is_List_Member (N) then
- declare
- P : constant Node_Id := Parent (N);
-
- begin
- 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;
-
- -- Otherwise, normal case where N is in a statement sequence,
- -- just put the post-call stuff after the call statement.
-
- else
- Insert_Actions_After (N, Post_Call);
- end if;
- end if;
-
- -- The call node itself is re-analyzed in Expand_Call
-
- end Expand_Actuals;
-
- -----------------
- -- Expand_Call --
- -----------------
-
- -- This procedure handles expansion of function calls and procedure call
- -- statements (i.e. it serves as the body for Expand_N_Function_Call and
- -- Expand_N_Procedure_Call_Statement). Processing for calls includes:
-
- -- Replace call to Raise_Exception by Raise_Exception_Always if possible
- -- Provide values of actuals for all formals in Extra_Formals list
- -- Replace "call" to enumeration literal function by literal itself
- -- Rewrite call to predefined operator as operator
- -- Replace actuals to in-out parameters that are numeric conversions,
- -- with explicit assignment to temporaries before and after the call.
- -- Remove optional actuals if First_Optional_Parameter specified.
-
- -- Note that the list of actuals has been filled with default expressions
- -- during semantic analysis of the call. Only the extra actuals required
- -- for the 'Constrained attribute and for accessibility checks are added
- -- at this point.
-
- procedure Expand_Call (N : Node_Id) is
- Loc : constant Source_Ptr := Sloc (N);
- Extra_Actuals : List_Id := No_List;
- Prev : Node_Id := Empty;
-
- procedure Add_Actual_Parameter (Insert_Param : Node_Id);
- -- Adds one entry to the end of the actual parameter list. Used for
- -- default parameters and for extra actuals (for Extra_Formals). The
- -- argument is an N_Parameter_Association node.
-
- procedure Add_Extra_Actual (Expr : Node_Id; EF : Entity_Id);
- -- Adds an extra actual to the list of extra actuals. Expr is the
- -- expression for the value of the actual, EF is the entity for the
- -- extra formal.
-
- function Inherited_From_Formal (S : Entity_Id) return Entity_Id;
- -- Within an instance, a type derived from a non-tagged formal derived
- -- type inherits from the original parent, not from the actual. The
- -- current derivation mechanism has the derived type inherit from the
- -- actual, which is only correct outside of the instance. If the
- -- subprogram is inherited, we test for this particular case through a
- -- convoluted tree traversal before setting the proper subprogram to be
- -- called.
-
- --------------------------
- -- Add_Actual_Parameter --
- --------------------------
-
- procedure Add_Actual_Parameter (Insert_Param : Node_Id) is
- Actual_Expr : constant Node_Id :=
- Explicit_Actual_Parameter (Insert_Param);
-
- begin
- -- Case of insertion is first named actual
-
- if No (Prev) or else
- Nkind (Parent (Prev)) /= N_Parameter_Association
- then
- Set_Next_Named_Actual (Insert_Param, First_Named_Actual (N));
- Set_First_Named_Actual (N, Actual_Expr);
-
- if No (Prev) then
- if No (Parameter_Associations (N)) then
- Set_Parameter_Associations (N, New_List);
- Append (Insert_Param, Parameter_Associations (N));
- end if;
- else
- Insert_After (Prev, Insert_Param);
- end if;
-
- -- Case of insertion is not first named actual
-
- else
- Set_Next_Named_Actual
- (Insert_Param, Next_Named_Actual (Parent (Prev)));
- Set_Next_Named_Actual (Parent (Prev), Actual_Expr);
- Append (Insert_Param, Parameter_Associations (N));
- end if;
-
- Prev := Actual_Expr;
- end Add_Actual_Parameter;
-
- ----------------------
- -- Add_Extra_Actual --
- ----------------------
-
- procedure Add_Extra_Actual (Expr : Node_Id; EF : Entity_Id) is
- Loc : constant Source_Ptr := Sloc (Expr);
-
- begin
- if Extra_Actuals = No_List then
- Extra_Actuals := New_List;
- Set_Parent (Extra_Actuals, N);
- end if;
-
- Append_To (Extra_Actuals,
- Make_Parameter_Association (Loc,
- Explicit_Actual_Parameter => Expr,
- Selector_Name =>
- Make_Identifier (Loc, Chars (EF))));
-
- Analyze_And_Resolve (Expr, Etype (EF));
- end Add_Extra_Actual;
-
- ---------------------------
- -- Inherited_From_Formal --
- ---------------------------
-
- function Inherited_From_Formal (S : Entity_Id) return Entity_Id is
- Par : Entity_Id;
- Gen_Par : Entity_Id;
- Gen_Prim : Elist_Id;
- Elmt : Elmt_Id;
- Indic : Node_Id;
-
- begin
- -- If the operation is inherited, it is attached to the corresponding
- -- type derivation. If the parent in the derivation is a generic
- -- actual, it is a subtype of the actual, and we have to recover the
- -- original derived type declaration to find the proper parent.
-
- if Nkind (Parent (S)) /= N_Full_Type_Declaration
- or else not Is_Derived_Type (Defining_Identifier (Parent (S)))
- or else Nkind (Type_Definition (Original_Node (Parent (S)))) /=
- N_Derived_Type_Definition
- or else not In_Instance
- then
- return Empty;
-
- else
- Indic :=
- (Subtype_Indication
- (Type_Definition (Original_Node (Parent (S)))));
-
- if Nkind (Indic) = N_Subtype_Indication then
- Par := Entity (Subtype_Mark (Indic));
- else
- Par := Entity (Indic);
- end if;
- end if;
-
- if not Is_Generic_Actual_Type (Par)
- or else Is_Tagged_Type (Par)
- or else Nkind (Parent (Par)) /= N_Subtype_Declaration
- or else not In_Open_Scopes (Scope (Par))
- then
- return Empty;
-
- else
- Gen_Par := Generic_Parent_Type (Parent (Par));
- end if;
-
- -- If the actual has no generic parent type, the formal is not
- -- a formal derived type, so nothing to inherit.
-
- if No (Gen_Par) then
- return Empty;
- end if;
-
- -- If the generic parent type is still the generic type, this is a
- -- private formal, not a derived formal, and there are no operations
- -- inherited from the formal.
-
- if Nkind (Parent (Gen_Par)) = N_Formal_Type_Declaration then
- return Empty;
- end if;
-
- Gen_Prim := Collect_Primitive_Operations (Gen_Par);
-
- Elmt := First_Elmt (Gen_Prim);
- while Present (Elmt) loop
- if Chars (Node (Elmt)) = Chars (S) then
- declare
- F1 : Entity_Id;
- F2 : Entity_Id;
-
- begin
- F1 := First_Formal (S);
- F2 := First_Formal (Node (Elmt));
- while Present (F1)
- and then Present (F2)
- loop
- if Etype (F1) = Etype (F2)
- or else Etype (F2) = Gen_Par
- then
- Next_Formal (F1);
- Next_Formal (F2);
- else
- Next_Elmt (Elmt);
- exit; -- not the right subprogram
- end if;
-
- return Node (Elmt);
- end loop;
- end;
-
- else
- Next_Elmt (Elmt);
- end if;
- end loop;
-
- raise Program_Error;
- end Inherited_From_Formal;
-
- -- Local variables
-
- Remote : constant Boolean := Is_Remote_Call (N);
- Actual : Node_Id;
- Formal : Entity_Id;
- Orig_Subp : Entity_Id := Empty;
- Param_Count : Natural := 0;
- Parent_Formal : Entity_Id;
- Parent_Subp : Entity_Id;
- Scop : Entity_Id;
- Subp : Entity_Id;
-
- Prev_Orig : Node_Id;
- -- Original node for an actual, which may have been rewritten. If the
- -- actual is a function call that has been transformed from a selected
- -- component, the original node is unanalyzed. Otherwise, it carries
- -- semantic information used to generate additional actuals.
-
- CW_Interface_Formals_Present : Boolean := False;
-
- -- Start of processing for Expand_Call
-
- begin
- -- Ignore if previous error
-
- if Nkind (N) in N_Has_Etype and then Etype (N) = Any_Type then
- return;
- end if;
-
- -- Call using access to subprogram with explicit dereference
-
- if Nkind (Name (N)) = N_Explicit_Dereference then
- Subp := Etype (Name (N));
- Parent_Subp := Empty;
-
- -- Case of call to simple entry, where the Name is a selected component
- -- whose prefix is the task, and whose selector name is the entry name
-
- elsif Nkind (Name (N)) = N_Selected_Component then
- Subp := Entity (Selector_Name (Name (N)));
- Parent_Subp := Empty;
-
- -- Case of call to member of entry family, where Name is an indexed
- -- component, with the prefix being a selected component giving the
- -- task and entry family name, and the index being the entry index.
-
- elsif Nkind (Name (N)) = N_Indexed_Component then
- Subp := Entity (Selector_Name (Prefix (Name (N))));
- Parent_Subp := Empty;
-
- -- Normal case
-
- else
- Subp := Entity (Name (N));
- Parent_Subp := Alias (Subp);
-
- -- Replace call to Raise_Exception by call to Raise_Exception_Always
- -- if we can tell that the first parameter cannot possibly be null.
- -- This improves efficiency by avoiding a run-time test.
-
- -- We do not do this if Raise_Exception_Always does not exist, which
- -- can happen in configurable run time profiles which provide only a
- -- Raise_Exception.
-
- if Is_RTE (Subp, RE_Raise_Exception)
- and then RTE_Available (RE_Raise_Exception_Always)
- then
- declare
- FA : constant Node_Id := Original_Node (First_Actual (N));
-
- begin
- -- The case we catch is where the first argument is obtained
- -- using the Identity attribute (which must always be
- -- non-null).
-
- if Nkind (FA) = N_Attribute_Reference
- and then Attribute_Name (FA) = Name_Identity
- then
- Subp := RTE (RE_Raise_Exception_Always);
- Set_Name (N, New_Occurrence_Of (Subp, Loc));
- end if;
- end;
- end if;
-
- if Ekind (Subp) = E_Entry then
- Parent_Subp := Empty;
- end if;
- end if;
-
- -- Ada 2005 (AI-345): We have a procedure call as a triggering
- -- alternative in an asynchronous select or as an entry call in
- -- a conditional or timed select. Check whether the procedure call
- -- is a renaming of an entry and rewrite it as an entry call.
-
- if Ada_Version >= Ada_05
- and then Nkind (N) = N_Procedure_Call_Statement
- and then
- ((Nkind (Parent (N)) = N_Triggering_Alternative
- and then Triggering_Statement (Parent (N)) = N)
- or else
- (Nkind (Parent (N)) = N_Entry_Call_Alternative
- and then Entry_Call_Statement (Parent (N)) = N))
- then
- declare
- Ren_Decl : Node_Id;
- Ren_Root : Entity_Id := Subp;
-
- begin
- -- This may be a chain of renamings, find the root
-
- if Present (Alias (Ren_Root)) then
- Ren_Root := Alias (Ren_Root);
- end if;
-
- if Present (Original_Node (Parent (Parent (Ren_Root)))) then
- Ren_Decl := Original_Node (Parent (Parent (Ren_Root)));
-
- if Nkind (Ren_Decl) = N_Subprogram_Renaming_Declaration then
- Rewrite (N,
- Make_Entry_Call_Statement (Loc,
- Name =>
- New_Copy_Tree (Name (Ren_Decl)),
- Parameter_Associations =>
- New_Copy_List_Tree (Parameter_Associations (N))));
-
- return;
- end if;
- end if;
- end;
- end if;
-
- -- First step, compute extra actuals, corresponding to any
- -- Extra_Formals present. Note that we do not access Extra_Formals
- -- directly, instead we simply note the presence of the extra
- -- formals as we process the regular formals and collect the
- -- corresponding actuals in Extra_Actuals.
-
- -- We also generate any required range checks for actuals as we go
- -- through the loop, since this is a convenient place to do this.
-
- Formal := First_Formal (Subp);
- Actual := First_Actual (N);
- Param_Count := 1;
- while Present (Formal) loop
-
- -- Generate range check if required (not activated yet ???)
-
--- if Do_Range_Check (Actual) then
--- Set_Do_Range_Check (Actual, False);
--- Generate_Range_Check
--- (Actual, Etype (Formal), CE_Range_Check_Failed);
--- end if;
-
- -- Prepare to examine current entry
-
- Prev := Actual;
- Prev_Orig := Original_Node (Prev);
-
- -- Ada 2005 (AI-251): Check if any formal is a class-wide interface
- -- to expand it in a further round.
-
- CW_Interface_Formals_Present :=
- CW_Interface_Formals_Present
- or else
- (Ekind (Etype (Formal)) = E_Class_Wide_Type
- and then Is_Interface (Etype (Etype (Formal))))
- or else
- (Ekind (Etype (Formal)) = E_Anonymous_Access_Type
- and then Is_Interface (Directly_Designated_Type
- (Etype (Etype (Formal)))));
-
- -- Create possible extra actual for constrained case. Usually, the
- -- extra actual is of the form actual'constrained, but since this
- -- attribute is only available for unconstrained records, TRUE is
- -- expanded if the type of the formal happens to be constrained (for
- -- instance when this procedure is inherited from an unconstrained
- -- record to a constrained one) or if the actual has no discriminant
- -- (its type is constrained). An exception to this is the case of a
- -- private type without discriminants. In this case we pass FALSE
- -- because the object has underlying discriminants with defaults.
-
- if Present (Extra_Constrained (Formal)) then
- if Ekind (Etype (Prev)) in Private_Kind
- and then not Has_Discriminants (Base_Type (Etype (Prev)))
- then
- Add_Extra_Actual
- (New_Occurrence_Of (Standard_False, Loc),
- Extra_Constrained (Formal));
-
- elsif Is_Constrained (Etype (Formal))
- or else not Has_Discriminants (Etype (Prev))
- then
- Add_Extra_Actual
- (New_Occurrence_Of (Standard_True, Loc),
- Extra_Constrained (Formal));
-
- -- Do not produce extra actuals for Unchecked_Union parameters.
- -- Jump directly to the end of the loop.
-
- elsif Is_Unchecked_Union (Base_Type (Etype (Actual))) then
- goto Skip_Extra_Actual_Generation;
-
- else
- -- If the actual is a type conversion, then the constrained
- -- test applies to the actual, not the target type.
-
- declare
- Act_Prev : Node_Id;
-
- begin
- -- Test for unchecked conversions as well, which can occur
- -- as out parameter actuals on calls to stream procedures.
-
- Act_Prev := Prev;
- while Nkind_In (Act_Prev, N_Type_Conversion,
- N_Unchecked_Type_Conversion)
- loop
- Act_Prev := Expression (Act_Prev);
- end loop;
-
- -- If the expression is a conversion of a dereference,
- -- this is internally generated code that manipulates
- -- addresses, e.g. when building interface tables. No
- -- check should occur in this case, and the discriminated
- -- object is not directly a hand.
-
- if not Comes_From_Source (Actual)
- and then Nkind (Actual) = N_Unchecked_Type_Conversion
- and then Nkind (Act_Prev) = N_Explicit_Dereference
- then
- Add_Extra_Actual
- (New_Occurrence_Of (Standard_False, Loc),
- Extra_Constrained (Formal));
-
- else
- Add_Extra_Actual
- (Make_Attribute_Reference (Sloc (Prev),
- Prefix =>
- Duplicate_Subexpr_No_Checks
- (Act_Prev, Name_Req => True),
- Attribute_Name => Name_Constrained),
- Extra_Constrained (Formal));
- end if;
- end;
- end if;
- end if;
-
- -- Create possible extra actual for accessibility level
-
- if Present (Extra_Accessibility (Formal)) then
-
- -- Ada 2005 (AI-252): If the actual was rewritten as an Access
- -- attribute, then the original actual may be an aliased object
- -- occurring as the prefix in a call using "Object.Operation"
- -- notation. In that case we must pass the level of the object,
- -- so Prev_Orig is reset to Prev and the attribute will be
- -- processed by the code for Access attributes further below.
-
- if Prev_Orig /= Prev
- and then Nkind (Prev) = N_Attribute_Reference
- and then
- Get_Attribute_Id (Attribute_Name (Prev)) = Attribute_Access
- and then Is_Aliased_View (Prev_Orig)
- then
- Prev_Orig := Prev;
- end if;
-
- -- Ada 2005 (AI-251): Thunks must propagate the extra actuals
- -- of accessibility levels.
-
- if Ekind (Current_Scope) in Subprogram_Kind
- and then Is_Thunk (Current_Scope)
- then
- declare
- Parm_Ent : Entity_Id;
-
- begin
- if Is_Controlling_Actual (Actual) then
-
- -- Find the corresponding actual of the thunk
-
- Parm_Ent := First_Entity (Current_Scope);
- for J in 2 .. Param_Count loop
- Next_Entity (Parm_Ent);
- end loop;
-
- else pragma Assert (Is_Entity_Name (Actual));
- Parm_Ent := Entity (Actual);
- end if;
-
- Add_Extra_Actual
- (New_Occurrence_Of (Extra_Accessibility (Parm_Ent), Loc),
- Extra_Accessibility (Formal));
- end;
-
- elsif Is_Entity_Name (Prev_Orig) then
-
- -- When passing an access parameter, or a renaming of an access
- -- parameter, as the actual to another access parameter we need
- -- to pass along the actual's own access level parameter. This
- -- is done if we are within the scope of the formal access
- -- parameter (if this is an inlined body the extra formal is
- -- irrelevant).
-
- if (Is_Formal (Entity (Prev_Orig))
- or else
- (Present (Renamed_Object (Entity (Prev_Orig)))
- and then
- Is_Entity_Name (Renamed_Object (Entity (Prev_Orig)))
- and then
- Is_Formal
- (Entity (Renamed_Object (Entity (Prev_Orig))))))
- and then Ekind (Etype (Prev_Orig)) = E_Anonymous_Access_Type
- and then In_Open_Scopes (Scope (Entity (Prev_Orig)))
- then
- declare
- Parm_Ent : constant Entity_Id := Param_Entity (Prev_Orig);
-
- begin
- pragma Assert (Present (Parm_Ent));
-
- if Present (Extra_Accessibility (Parm_Ent)) then
- Add_Extra_Actual
- (New_Occurrence_Of
- (Extra_Accessibility (Parm_Ent), Loc),
- Extra_Accessibility (Formal));
-
- -- If the actual access parameter does not have an
- -- associated extra formal providing its scope level,
- -- then treat the actual as having library-level
- -- accessibility.
-
- else
- Add_Extra_Actual
- (Make_Integer_Literal (Loc,
- Intval => Scope_Depth (Standard_Standard)),
- Extra_Accessibility (Formal));
- end if;
- end;
-
- -- The actual is a normal access value, so just pass the level
- -- of the actual's access type.
-
- else
- Add_Extra_Actual
- (Make_Integer_Literal (Loc,
- Intval => Type_Access_Level (Etype (Prev_Orig))),
- Extra_Accessibility (Formal));
- end if;
-
- -- If the actual is an access discriminant, then pass the level
- -- of the enclosing object (RM05-3.10.2(12.4/2)).
-
- elsif Nkind (Prev_Orig) = N_Selected_Component
- and then Ekind (Entity (Selector_Name (Prev_Orig))) =
- E_Discriminant
- and then Ekind (Etype (Entity (Selector_Name (Prev_Orig)))) =
- E_Anonymous_Access_Type
- then
- Add_Extra_Actual
- (Make_Integer_Literal (Loc,
- Intval => Object_Access_Level (Prefix (Prev_Orig))),
- Extra_Accessibility (Formal));
-
- -- All other cases
-
- else
- case Nkind (Prev_Orig) is
-
- when N_Attribute_Reference =>
- case Get_Attribute_Id (Attribute_Name (Prev_Orig)) is
-
- -- 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));
-
- -- Treat the unchecked attributes as library-level
-
- when Attribute_Unchecked_Access |
- Attribute_Unrestricted_Access =>
- Add_Extra_Actual
- (Make_Integer_Literal (Loc,
- Intval => Scope_Depth (Standard_Standard)),
- Extra_Accessibility (Formal));
-
- -- No other cases of attributes returning access
- -- values that can be passed to access parameters
-
- when others =>
- raise Program_Error;
-
- end case;
-
- -- For allocators we pass the level of the execution of
- -- the called subprogram, which is one greater than the
- -- current scope level.
-
- when N_Allocator =>
- Add_Extra_Actual
- (Make_Integer_Literal (Loc,
- 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.
-
- when others =>
- Add_Extra_Actual
- (Make_Integer_Literal (Loc,
- Intval => Type_Access_Level (Etype (Prev))),
- Extra_Accessibility (Formal));
-
- end case;
- end if;
- end if;
-
- -- Perform the check of 4.6(49) that prevents a null value from being
- -- passed as an actual to an access parameter. Note that the check is
- -- elided in the common cases of passing an access attribute or
- -- access parameter as an actual. Also, we currently don't enforce
- -- this check for expander-generated actuals and when -gnatdj is set.
-
- if Ada_Version >= Ada_05 then
-
- -- Ada 2005 (AI-231): Check null-excluding access types
-
- if Is_Access_Type (Etype (Formal))
- and then Can_Never_Be_Null (Etype (Formal))
- and then Nkind (Prev) /= N_Raise_Constraint_Error
- and then (Known_Null (Prev)
- or else not Can_Never_Be_Null (Etype (Prev)))
- then
- Install_Null_Excluding_Check (Prev);
- end if;
-
- -- Ada_Version < Ada_05
-
- else
- if Ekind (Etype (Formal)) /= E_Anonymous_Access_Type
- or else Access_Checks_Suppressed (Subp)
- then
- null;
-
- elsif Debug_Flag_J then
- null;
-
- elsif not Comes_From_Source (Prev) then
- null;
-
- elsif Is_Entity_Name (Prev)
- and then Ekind (Etype (Prev)) = E_Anonymous_Access_Type
- then
- null;
-
- elsif Nkind_In (Prev, N_Allocator, N_Attribute_Reference) then
- null;
-
- -- Suppress null checks when passing to access parameters of Java
- -- and CIL subprograms. (Should this be done for other foreign
- -- conventions as well ???)
-
- elsif Convention (Subp) = Convention_Java
- or else Convention (Subp) = Convention_CIL
- then
- null;
-
- else
- Install_Null_Excluding_Check (Prev);
- end if;
- end if;
-
- -- Perform appropriate validity checks on parameters that
- -- are entities.
-
- if Validity_Checks_On then
- if (Ekind (Formal) = E_In_Parameter
- and then Validity_Check_In_Params)
- or else
- (Ekind (Formal) = E_In_Out_Parameter
- 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
- -- meets this condition), it has not been expanded yet. It will
- -- be copied in the validity code that follows, and has to be
- -- expanded appropriately, so reanalyze it.
-
- -- What we do is just to unset analyzed bits on prefixes till
- -- we reach something that does not have a prefix.
-
- declare
- Nod : Node_Id;
-
- begin
- Nod := Actual;
- while Nkind_In (Nod, N_Indexed_Component,
- N_Selected_Component)
- loop
- Set_Analyzed (Nod, False);
- Nod := Prefix (Nod);
- end loop;
- end;
-
- Ensure_Valid (Actual);
- end if;
- 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
- -- calls explicitly generate any required checks. We also need it
- -- only if we are doing standard validity checks, since clearly it
- -- is not needed if validity checks are off, and in subscript
- -- validity checking mode, all indexed components are checked with
- -- a call directly from Expand_N_Indexed_Component.
-
- if Comes_From_Source (N)
- and then Ekind (Formal) /= E_In_Parameter
- and then Validity_Checks_On
- and then Validity_Check_Default
- and then not Validity_Check_Subscripts
- then
- Check_Valid_Lvalue_Subscripts (Actual);
- end if;
-
- -- Mark any scalar OUT parameter that is a simple variable as no
- -- longer known to be valid (unless the type is always valid). This
- -- reflects the fact that if an OUT parameter is never set in a
- -- procedure, then it can become invalid on the procedure return.
-
- if Ekind (Formal) = E_Out_Parameter
- and then Is_Entity_Name (Actual)
- and then Ekind (Entity (Actual)) = E_Variable
- and then not Is_Known_Valid (Etype (Actual))
- then
- Set_Is_Known_Valid (Entity (Actual), False);
- end if;
-
- -- For an OUT or IN OUT parameter, if the actual is an entity, then
- -- clear current values, since they can be clobbered. We are probably
- -- doing this in more places than we need to, but better safe than
- -- sorry when it comes to retaining bad current values!
-
- if Ekind (Formal) /= E_In_Parameter
- and then Is_Entity_Name (Actual)
- and then Present (Entity (Actual))
- then
- declare
- Ent : constant Entity_Id := Entity (Actual);
- Sav : Node_Id;
-
- begin
- -- For an OUT or IN OUT parameter that is an assignable entity,
- -- we do not want to clobber the Last_Assignment field, since
- -- if it is set, it was precisely because it is indeed an OUT
- -- or IN OUT parameter!
-
- if (Ekind (Formal) = E_Out_Parameter
- or else
- Ekind (Formal) = E_In_Out_Parameter)
- and then Is_Assignable (Ent)
- then
- Sav := Last_Assignment (Ent);
- Kill_Current_Values (Ent);
- Set_Last_Assignment (Ent, Sav);
-
- -- For all other cases, just kill the current values
-
- else
- Kill_Current_Values (Ent);
- end if;
- end;
- end if;
-
- -- If the formal is class wide and the actual is an aggregate, force
- -- evaluation so that the back end who does not know about class-wide
- -- type, does not generate a temporary of the wrong size.
-
- if not Is_Class_Wide_Type (Etype (Formal)) then
- null;
-
- elsif Nkind (Actual) = N_Aggregate
- or else (Nkind (Actual) = N_Qualified_Expression
- and then Nkind (Expression (Actual)) = N_Aggregate)
- then
- Force_Evaluation (Actual);
- end if;
-
- -- In a remote call, if the formal is of a class-wide type, check
- -- that the actual meets the requirements described in E.4(18).
-
- if Remote and then Is_Class_Wide_Type (Etype (Formal)) then
- Insert_Action (Actual,
- Make_Transportable_Check (Loc,
- Duplicate_Subexpr_Move_Checks (Actual)));
- end if;
-
- -- This label is required when skipping extra actual generation for
- -- Unchecked_Union parameters.
-
- <<Skip_Extra_Actual_Generation>>
-
- Param_Count := Param_Count + 1;
- Next_Actual (Actual);
- Next_Formal (Formal);
- end loop;
-
- -- 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
- -- assignment might be transformed to a declaration for an unconstrained
- -- value if the expression is classwide.
-
- if Nkind (N) = N_Function_Call
- and then Is_Tag_Indeterminate (N)
- and then Is_Entity_Name (Name (N))
- then
- declare
- Ass : Node_Id := Empty;
-
- begin
- if Nkind (Parent (N)) = N_Assignment_Statement then
- Ass := Parent (N);
-
- elsif Nkind (Parent (N)) = N_Qualified_Expression
- and then Nkind (Parent (Parent (N))) = N_Assignment_Statement
- then
- Ass := Parent (Parent (N));
-
- elsif Nkind (Parent (N)) = N_Explicit_Dereference
- and then Nkind (Parent (Parent (N))) = N_Assignment_Statement
- then
- Ass := Parent (Parent (N));
- end if;
-
- if Present (Ass)
- and then Is_Class_Wide_Type (Etype (Name (Ass)))
- then
- if Is_Access_Type (Etype (N)) then
- if Designated_Type (Etype (N)) /=
- Root_Type (Etype (Name (Ass)))
- then
- Error_Msg_NE
- ("tag-indeterminate expression "
- & " must have designated type& (RM 5.2 (6))",
- N, Root_Type (Etype (Name (Ass))));
- else
- Propagate_Tag (Name (Ass), N);
- end if;
-
- elsif Etype (N) /= Root_Type (Etype (Name (Ass))) then
- Error_Msg_NE
- ("tag-indeterminate expression must have type&"
- & "(RM 5.2 (6))", N, Root_Type (Etype (Name (Ass))));
-
- else
- Propagate_Tag (Name (Ass), N);
- end if;
-
- -- The call will be rewritten as a dispatching call, and
- -- expanded as such.
-
- return;
- end if;
- end;
- end if;
-
- -- Ada 2005 (AI-251): If some formal is a class-wide interface, expand
- -- it to point to the correct secondary virtual table
-
- if Nkind_In (N, N_Function_Call, N_Procedure_Call_Statement)
- and then CW_Interface_Formals_Present
- then
- Expand_Interface_Actuals (N);
- end if;
-
- -- Deals with Dispatch_Call if we still have a call, before expanding
- -- extra actuals since this will be done on the re-analysis of the
- -- dispatching call. Note that we do not try to shorten the actual
- -- list for a dispatching call, it would not make sense to do so.
- -- Expansion of dispatching calls is suppressed when VM_Target, because
- -- the VM back-ends directly handle the generation of dispatching
- -- calls and would have to undo any expansion to an indirect call.
-
- if Nkind_In (N, N_Function_Call, N_Procedure_Call_Statement)
- and then Present (Controlling_Argument (N))
- then
- if VM_Target = No_VM then
- Expand_Dispatching_Call (N);
-
- -- The following return is worrisome. Is it really OK to
- -- skip all remaining processing in this procedure ???
-
- return;
-
- -- Expansion of a dispatching call results in an indirect call, which
- -- in turn causes current values to be killed (see Resolve_Call), so
- -- on VM targets we do the call here to ensure consistent warnings
- -- between VM and non-VM targets.
-
- else
- Kill_Current_Values;
- end if;
- end if;
-
- -- Similarly, expand calls to RCI subprograms on which pragma
- -- All_Calls_Remote applies. The rewriting will be reanalyzed
- -- later. Do this only when the call comes from source since we do
- -- not want such a rewriting to occur in expanded code.
-
- if Is_All_Remote_Call (N) then
- Expand_All_Calls_Remote_Subprogram_Call (N);
-
- -- Similarly, do not add extra actuals for an entry call whose entity
- -- is a protected procedure, or for an internal protected subprogram
- -- call, because it will be rewritten as a protected subprogram call
- -- and reanalyzed (see Expand_Protected_Subprogram_Call).
-
- elsif Is_Protected_Type (Scope (Subp))
- and then (Ekind (Subp) = E_Procedure
- or else Ekind (Subp) = E_Function)
- then
- null;
-
- -- During that loop we gathered the extra actuals (the ones that
- -- correspond to Extra_Formals), so now they can be appended.
-
- else
- while Is_Non_Empty_List (Extra_Actuals) loop
- Add_Actual_Parameter (Remove_Head (Extra_Actuals));
- end loop;
- end if;
-
- -- At this point we have all the actuals, so this is the point at
- -- which the various expansion activities for actuals is carried out.
-
- Expand_Actuals (N, Subp);
-
- -- If the subprogram is a renaming, or if it is inherited, replace it
- -- in the call with the name of the actual subprogram being called.
- -- If this is a dispatching call, the run-time decides what to call.
- -- The Alias attribute does not apply to entries.
-
- if Nkind (N) /= N_Entry_Call_Statement
- and then No (Controlling_Argument (N))
- and then Present (Parent_Subp)
- then
- if Present (Inherited_From_Formal (Subp)) then
- Parent_Subp := Inherited_From_Formal (Subp);
- else
- while Present (Alias (Parent_Subp)) loop
- Parent_Subp := Alias (Parent_Subp);
- end loop;
- end if;
-
- -- The below setting of Entity is suspect, see F109-018 discussion???
-
- Set_Entity (Name (N), Parent_Subp);
-
- if Is_Abstract_Subprogram (Parent_Subp)
- and then not In_Instance
- then
- Error_Msg_NE
- ("cannot call abstract subprogram &!", Name (N), Parent_Subp);
- end if;
-
- -- Inspect all formals of derived subprogram Subp. Compare parameter
- -- types with the parent subprogram and check whether an actual may
- -- need a type conversion to the corresponding formal of the parent
- -- subprogram.
-
- -- Not clear whether intrinsic subprograms need such conversions. ???
-
- if not Is_Intrinsic_Subprogram (Parent_Subp)
- or else Is_Generic_Instance (Parent_Subp)
- then
- declare
- procedure Convert (Act : Node_Id; Typ : Entity_Id);
- -- Rewrite node Act as a type conversion of Act to Typ. Analyze
- -- and resolve the newly generated construct.
-
- -------------
- -- Convert --
- -------------
-
- procedure Convert (Act : Node_Id; Typ : Entity_Id) is
- begin
- Rewrite (Act, OK_Convert_To (Typ, Relocate_Node (Act)));
- Analyze (Act);
- Resolve (Act, Typ);
- end Convert;
-
- -- Local variables
-
- Actual_Typ : Entity_Id;
- Formal_Typ : Entity_Id;
- Parent_Typ : Entity_Id;
-
- begin
- Actual := First_Actual (N);
- Formal := First_Formal (Subp);
- Parent_Formal := First_Formal (Parent_Subp);
- while Present (Formal) loop
- Actual_Typ := Etype (Actual);
- Formal_Typ := Etype (Formal);
- Parent_Typ := Etype (Parent_Formal);
-
- -- For an IN parameter of a scalar type, the parent formal
- -- type and derived formal type differ or the parent formal
- -- type and actual type do not match statically.
-
- if Is_Scalar_Type (Formal_Typ)
- and then Ekind (Formal) = E_In_Parameter
- and then Formal_Typ /= Parent_Typ
- and then
- not Subtypes_Statically_Match (Parent_Typ, Actual_Typ)
- and then not Raises_Constraint_Error (Actual)
- then
- Convert (Actual, Parent_Typ);
- Enable_Range_Check (Actual);
-
- -- For access types, the parent formal type and actual type
- -- differ.
-
- elsif Is_Access_Type (Formal_Typ)
- and then Base_Type (Parent_Typ) /= Base_Type (Actual_Typ)
- then
- if Ekind (Formal) /= E_In_Parameter then
- Convert (Actual, Parent_Typ);
-
- elsif Ekind (Parent_Typ) = E_Anonymous_Access_Type
- and then Designated_Type (Parent_Typ) /=
- Designated_Type (Actual_Typ)
- and then not Is_Controlling_Formal (Formal)
- then
- -- This unchecked conversion is not necessary unless
- -- inlining is enabled, because in that case the type
- -- mismatch may become visible in the body about to be
- -- inlined.
-
- Rewrite (Actual,
- Unchecked_Convert_To (Parent_Typ,
- Relocate_Node (Actual)));
-
- Analyze (Actual);
- Resolve (Actual, Parent_Typ);
- end if;
-
- -- For array and record types, the parent formal type and
- -- derived formal type have different sizes or pragma Pack
- -- status.
-
- elsif ((Is_Array_Type (Formal_Typ)
- and then Is_Array_Type (Parent_Typ))
- or else
- (Is_Record_Type (Formal_Typ)
- and then Is_Record_Type (Parent_Typ)))
- and then
- (Esize (Formal_Typ) /= Esize (Parent_Typ)
- or else Has_Pragma_Pack (Formal_Typ) /=
- Has_Pragma_Pack (Parent_Typ))
- then
- Convert (Actual, Parent_Typ);
- end if;
-
- Next_Actual (Actual);
- Next_Formal (Formal);
- Next_Formal (Parent_Formal);
- end loop;
- end;
- end if;
-
- Orig_Subp := Subp;
- Subp := Parent_Subp;
- end if;
-
- -- Check for violation of No_Abort_Statements
-
- if Is_RTE (Subp, RE_Abort_Task) then
- Check_Restriction (No_Abort_Statements, N);
-
- -- Check for violation of No_Dynamic_Attachment
-
- elsif RTU_Loaded (Ada_Interrupts)
- and then (Is_RTE (Subp, RE_Is_Reserved) or else
- Is_RTE (Subp, RE_Is_Attached) or else
- Is_RTE (Subp, RE_Current_Handler) or else
- Is_RTE (Subp, RE_Attach_Handler) or else
- Is_RTE (Subp, RE_Exchange_Handler) or else
- Is_RTE (Subp, RE_Detach_Handler) or else
- Is_RTE (Subp, RE_Reference))
- then
- Check_Restriction (No_Dynamic_Attachment, N);
- end if;
-
- -- Deal with case where call is an explicit dereference
-
- if Nkind (Name (N)) = N_Explicit_Dereference then
-
- -- Handle case of access to protected subprogram type
-
- if Is_Access_Protected_Subprogram_Type
- (Base_Type (Etype (Prefix (Name (N)))))
- then
- -- If this is a call through an access to protected operation,
- -- the prefix has the form (object'address, operation'access).
- -- Rewrite as a for other protected calls: the object is the
- -- first parameter of the list of actuals.
-
- declare
- Call : Node_Id;
- Parm : List_Id;
- Nam : Node_Id;
- Obj : Node_Id;
- Ptr : constant Node_Id := Prefix (Name (N));
-
- T : constant Entity_Id :=
- Equivalent_Type (Base_Type (Etype (Ptr)));
-
- D_T : constant Entity_Id :=
- Designated_Type (Base_Type (Etype (Ptr)));
-
- begin
- Obj :=
- Make_Selected_Component (Loc,
- Prefix => Unchecked_Convert_To (T, Ptr),
- Selector_Name =>
- New_Occurrence_Of (First_Entity (T), Loc));
-
- Nam :=
- Make_Selected_Component (Loc,
- Prefix => Unchecked_Convert_To (T, Ptr),
- Selector_Name =>
- New_Occurrence_Of (Next_Entity (First_Entity (T)), Loc));
-
- Nam :=
- Make_Explicit_Dereference (Loc,
- Prefix => Nam);
-
- if Present (Parameter_Associations (N)) then
- Parm := Parameter_Associations (N);
- else
- Parm := New_List;
- end if;
-
- Prepend (Obj, Parm);
-
- if Etype (D_T) = Standard_Void_Type then
- Call :=
- Make_Procedure_Call_Statement (Loc,
- Name => Nam,
- Parameter_Associations => Parm);
- else
- Call :=
- Make_Function_Call (Loc,
- Name => Nam,
- Parameter_Associations => Parm);
- end if;
-
- Set_First_Named_Actual (Call, First_Named_Actual (N));
- Set_Etype (Call, Etype (D_T));
-
- -- We do not re-analyze the call to avoid infinite recursion.
- -- We analyze separately the prefix and the object, and set
- -- the checks on the prefix that would otherwise be emitted
- -- when resolving a call.
-
- Rewrite (N, Call);
- Analyze (Nam);
- Apply_Access_Check (Nam);
- Analyze (Obj);
- return;
- end;
- end if;
- end if;
-
- -- If this is a call to an intrinsic subprogram, then perform the
- -- appropriate expansion to the corresponding tree node and we
- -- are all done (since after that the call is gone!)
-
- -- In the case where the intrinsic is to be processed by the back end,
- -- the call to Expand_Intrinsic_Call will do nothing, which is fine,
- -- since the idea in this case is to pass the call unchanged.
- -- If the intrinsic is an inherited unchecked conversion, and the
- -- derived type is the target type of the conversion, we must retain
- -- it as the return type of the expression. Otherwise the expansion
- -- below, which uses the parent operation, will yield the wrong type.
-
- if Is_Intrinsic_Subprogram (Subp) then
- Expand_Intrinsic_Call (N, Subp);
-
- if Nkind (N) = N_Unchecked_Type_Conversion
- and then Parent_Subp /= Orig_Subp
- and then Etype (Parent_Subp) /= Etype (Orig_Subp)
- then
- Set_Etype (N, Etype (Orig_Subp));
- end if;
-
- return;
- end if;
-
- if Ekind (Subp) = E_Function
- or else Ekind (Subp) = E_Procedure
- then
- if Is_Inlined (Subp) then
-
- Inlined_Subprogram : declare
- Bod : Node_Id;
- Must_Inline : Boolean := False;
- Spec : constant Node_Id := Unit_Declaration_Node (Subp);
- Scop : constant Entity_Id := Scope (Subp);
-
- function In_Unfrozen_Instance return Boolean;
- -- If the subprogram comes from an instance in the same
- -- unit, and the instance is not yet frozen, inlining might
- -- trigger order-of-elaboration problems in gigi.
-
- --------------------------
- -- In_Unfrozen_Instance --
- --------------------------
-
- function In_Unfrozen_Instance return Boolean is
- S : Entity_Id;
-
- begin
- S := Scop;
- while Present (S)
- and then S /= Standard_Standard
- loop
- if Is_Generic_Instance (S)
- and then Present (Freeze_Node (S))
- and then not Analyzed (Freeze_Node (S))
- then
- return True;
- end if;
-
- S := Scope (S);
- end loop;
-
- return False;
- end In_Unfrozen_Instance;
-
- -- Start of processing for Inlined_Subprogram
-
- begin
- -- Verify that the body to inline has already been seen, and
- -- that if the body is in the current unit the inlining does
- -- not occur earlier. This avoids order-of-elaboration problems
- -- in the back end.
-
- -- This should be documented in sinfo/einfo ???
-
- if No (Spec)
- or else Nkind (Spec) /= N_Subprogram_Declaration
- or else No (Body_To_Inline (Spec))
- then
- Must_Inline := False;
-
- -- If this an inherited function that returns a private
- -- type, do not inline if the full view is an unconstrained
- -- array, because such calls cannot be inlined.
-
- elsif Present (Orig_Subp)
- and then Is_Array_Type (Etype (Orig_Subp))
- and then not Is_Constrained (Etype (Orig_Subp))
- then
- Must_Inline := False;
-
- elsif In_Unfrozen_Instance then
- Must_Inline := False;
-
- else
- Bod := Body_To_Inline (Spec);
-
- if (In_Extended_Main_Code_Unit (N)
- or else In_Extended_Main_Code_Unit (Parent (N))
- or else Has_Pragma_Inline_Always (Subp))
- and then (not In_Same_Extended_Unit (Sloc (Bod), Loc)
- or else
- Earlier_In_Extended_Unit (Sloc (Bod), Loc))
- then
- Must_Inline := True;
-
- -- If we are compiling a package body that is not the main
- -- unit, it must be for inlining/instantiation purposes,
- -- in which case we inline the call to insure that the same
- -- temporaries are generated when compiling the body by
- -- itself. Otherwise link errors can occur.
-
- -- If the function being called is itself in the main unit,
- -- we cannot inline, because there is a risk of double
- -- elaboration and/or circularity: the inlining can make
- -- visible a private entity in the body of the main unit,
- -- that gigi will see before its sees its proper definition.
-
- elsif not (In_Extended_Main_Code_Unit (N))
- and then In_Package_Body
- then
- Must_Inline := not In_Extended_Main_Source_Unit (Subp);
- end if;
- end if;
-
- if Must_Inline then
- Expand_Inlined_Call (N, Subp, Orig_Subp);
-
- else
- -- Let the back end handle it
-
- Add_Inlined_Body (Subp);
-
- if Front_End_Inlining
- and then Nkind (Spec) = N_Subprogram_Declaration
- and then (In_Extended_Main_Code_Unit (N))
- and then No (Body_To_Inline (Spec))
- and then not Has_Completion (Subp)
- and then In_Same_Extended_Unit (Sloc (Spec), Loc)
- then
- Cannot_Inline
- ("cannot inline& (body not seen yet)?",
- N, Subp);
- end if;
- end if;
- end Inlined_Subprogram;
- end if;
- end if;
-
- -- Check for a protected subprogram. This is either an intra-object
- -- call, or a protected function call. Protected procedure calls are
- -- rewritten as entry calls and handled accordingly.
-
- -- In Ada 2005, this may be an indirect call to an access parameter
- -- that is an access_to_subprogram. In that case the anonymous type
- -- has a scope that is a protected operation, but the call is a
- -- regular one.
-
- Scop := Scope (Subp);
-
- if Nkind (N) /= N_Entry_Call_Statement
- and then Is_Protected_Type (Scop)
- and then Ekind (Subp) /= E_Subprogram_Type
- then
- -- If the call is an internal one, it is rewritten as a call to
- -- to the corresponding unprotected subprogram.
-
- Expand_Protected_Subprogram_Call (N, Subp, Scop);
- end if;
-
- -- Functions returning controlled objects need special attention
- -- If the return type is limited the context is an initialization
- -- and different processing applies.
-
- if Needs_Finalization (Etype (Subp))
- and then not Is_Inherently_Limited_Type (Etype (Subp))
- and then not Is_Limited_Interface (Etype (Subp))
- then
- Expand_Ctrl_Function_Call (N);
- end if;
-
- -- Test for First_Optional_Parameter, and if so, truncate parameter
- -- list if there are optional parameters at the trailing end.
- -- Note we never delete procedures for call via a pointer.
-
- if (Ekind (Subp) = E_Procedure or else Ekind (Subp) = E_Function)
- and then Present (First_Optional_Parameter (Subp))
- then
- declare
- Last_Keep_Arg : Node_Id;
-
- begin
- -- Last_Keep_Arg will hold the last actual that should be
- -- retained. If it remains empty at the end, it means that
- -- all parameters are optional.
-
- Last_Keep_Arg := Empty;
-
- -- Find first optional parameter, must be present since we
- -- checked the validity of the parameter before setting it.
-
- Formal := First_Formal (Subp);
- Actual := First_Actual (N);
- while Formal /= First_Optional_Parameter (Subp) loop
- Last_Keep_Arg := Actual;
- Next_Formal (Formal);
- Next_Actual (Actual);
- end loop;
-
- -- We have Formal and Actual pointing to the first potentially
- -- droppable argument. We can drop all the trailing arguments
- -- whose actual matches the default. Note that we know that all
- -- remaining formals have defaults, because we checked that this
- -- requirement was met before setting First_Optional_Parameter.
-
- -- We use Fully_Conformant_Expressions to check for identity
- -- between formals and actuals, which may miss some cases, but
- -- on the other hand, this is only an optimization (if we fail
- -- to truncate a parameter it does not affect functionality).
- -- So if the default is 3 and the actual is 1+2, we consider
- -- them unequal, which hardly seems worrisome.
-
- while Present (Formal) loop
- if not Fully_Conformant_Expressions
- (Actual, Default_Value (Formal))
- then
- Last_Keep_Arg := Actual;
- end if;
-
- Next_Formal (Formal);
- Next_Actual (Actual);
- end loop;
-
- -- If no arguments, delete entire list, this is the easy case
-
- if No (Last_Keep_Arg) then
- Set_Parameter_Associations (N, No_List);
- Set_First_Named_Actual (N, Empty);
-
- -- Case where at the last retained argument is positional. This
- -- is also an easy case, since the retained arguments are already
- -- in the right form, and we don't need to worry about the order
- -- of arguments that get eliminated.
-
- elsif Is_List_Member (Last_Keep_Arg) then
- while Present (Next (Last_Keep_Arg)) loop
- Discard_Node (Remove_Next (Last_Keep_Arg));
- end loop;
-
- Set_First_Named_Actual (N, Empty);
-
- -- This is the annoying case where the last retained argument
- -- is a named parameter. Since the original arguments are not
- -- in declaration order, we may have to delete some fairly
- -- random collection of arguments.
-
- else
- declare
- Temp : Node_Id;
- Passoc : Node_Id;
-
- begin
- -- First step, remove all the named parameters from the
- -- list (they are still chained using First_Named_Actual
- -- and Next_Named_Actual, so we have not lost them!)
-
- Temp := First (Parameter_Associations (N));
-
- -- Case of all parameters named, remove them all
-
- if Nkind (Temp) = N_Parameter_Association then
- while Is_Non_Empty_List (Parameter_Associations (N)) loop
- Temp := Remove_Head (Parameter_Associations (N));
- end loop;
-
- -- Case of mixed positional/named, remove named parameters
-
- else
- while Nkind (Next (Temp)) /= N_Parameter_Association loop
- Next (Temp);
- end loop;
-
- while Present (Next (Temp)) loop
- Remove (Next (Temp));
- end loop;
- end if;
-
- -- Now we loop through the named parameters, till we get
- -- to the last one to be retained, adding them to the list.
- -- Note that the Next_Named_Actual list does not need to be
- -- touched since we are only reordering them on the actual
- -- parameter association list.
-
- Passoc := Parent (First_Named_Actual (N));
- loop
- Temp := Relocate_Node (Passoc);
- Append_To
- (Parameter_Associations (N), Temp);
- exit when
- Last_Keep_Arg = Explicit_Actual_Parameter (Passoc);
- Passoc := Parent (Next_Named_Actual (Passoc));
- end loop;
-
- Set_Next_Named_Actual (Temp, Empty);
-
- loop
- Temp := Next_Named_Actual (Passoc);
- exit when No (Temp);
- Set_Next_Named_Actual
- (Passoc, Next_Named_Actual (Parent (Temp)));
- end loop;
- end;
- end if;
- end;
- end if;
- end Expand_Call;
-
- --------------------------
- -- Expand_Inlined_Call --
- --------------------------
-
- procedure Expand_Inlined_Call
- (N : Node_Id;
- Subp : Entity_Id;
- Orig_Subp : Entity_Id)
- is
- Loc : constant Source_Ptr := Sloc (N);
- Is_Predef : constant Boolean :=
- Is_Predefined_File_Name
- (Unit_File_Name (Get_Source_Unit (Subp)));
- Orig_Bod : constant Node_Id :=
- Body_To_Inline (Unit_Declaration_Node (Subp));
-
- Blk : Node_Id;
- Bod : Node_Id;
- Decl : Node_Id;
- Decls : constant List_Id := New_List;
- Exit_Lab : Entity_Id := Empty;
- F : Entity_Id;
- A : Node_Id;
- Lab_Decl : Node_Id;
- Lab_Id : Node_Id;
- New_A : Node_Id;
- Num_Ret : Int := 0;
- Ret_Type : Entity_Id;
- Targ : Node_Id;
- Targ1 : Node_Id;
- Temp : Entity_Id;
- Temp_Typ : Entity_Id;
-
- Is_Unc : constant Boolean :=
- 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.
-
- function Is_Null_Procedure return Boolean;
- -- Predicate to recognize stubbed procedures and null procedures, for
- -- which there is no need for the full inlining mechanism.
-
- procedure Make_Exit_Label;
- -- Build declaration for exit label to be used in Return statements
-
- function Process_Formals (N : Node_Id) return Traverse_Result;
- -- Replace occurrence of a formal with the corresponding actual, or
- -- the thunk generated for it.
-
- function Process_Sloc (Nod : Node_Id) return Traverse_Result;
- -- If the call being expanded is that of an internal subprogram,
- -- set the sloc of the generated block to that of the call itself,
- -- so that the expansion is skipped by the -next- command in gdb.
- -- Same processing for a subprogram in a predefined file, e.g.
- -- Ada.Tags. If Debug_Generated_Code is true, suppress this change
- -- to simplify our own development.
-
- procedure Rewrite_Function_Call (N : Node_Id; Blk : Node_Id);
- -- If the function body is a single expression, replace call with
- -- expression, else insert block appropriately.
-
- procedure Rewrite_Procedure_Call (N : Node_Id; Blk : Node_Id);
- -- If procedure body has no local variables, inline body without
- -- creating block, otherwise rewrite call with block.
-
- function Formal_Is_Used_Once (Formal : Entity_Id) return Boolean;
- -- Determine whether a formal parameter is used only once in Orig_Bod
-
- -----------------------
- -- Is_Null_Procedure --
- -----------------------
-
- function Is_Null_Procedure return Boolean is
- Decl : constant Node_Id := Unit_Declaration_Node (Subp);
-
- begin
- if Ekind (Subp) /= E_Procedure then
- return False;
-
- elsif Nkind (Orig_Bod) /= N_Subprogram_Body then
- return False;
-
- -- Check if this is an Ada 2005 null procedure
-
- elsif Nkind (Decl) = N_Subprogram_Declaration
- and then Null_Present (Specification (Decl))
- then
- return True;
-
- -- Check if the body contains only a null statement, followed by the
- -- return statement added during expansion.
-
- else
- declare
- Stat : constant Node_Id :=
- First
- (Statements (Handled_Statement_Sequence (Orig_Bod)));
-
- Stat2 : constant Node_Id := Next (Stat);
-
- begin
- return
- Nkind (Stat) = N_Null_Statement
- and then
- (No (Stat2)
- or else
- (Nkind (Stat2) = N_Simple_Return_Statement
- and then No (Next (Stat2))));
- end;
- end if;
- end Is_Null_Procedure;
-
- ---------------------
- -- Make_Exit_Label --
- ---------------------
-
- procedure Make_Exit_Label is
- begin
- -- Create exit label for subprogram if one does not exist yet
-
- if No (Exit_Lab) then
- Lab_Id :=
- Make_Identifier (Loc,
- Chars => New_Internal_Name ('L'));
- Set_Entity (Lab_Id,
- Make_Defining_Identifier (Loc, Chars (Lab_Id)));
- Exit_Lab := Make_Label (Loc, Lab_Id);
-
- Lab_Decl :=
- Make_Implicit_Label_Declaration (Loc,
- Defining_Identifier => Entity (Lab_Id),
- Label_Construct => Exit_Lab);
- end if;
- end Make_Exit_Label;
-
- ---------------------
- -- Process_Formals --
- ---------------------
-
- function Process_Formals (N : Node_Id) return Traverse_Result is
- A : Entity_Id;
- E : Entity_Id;
- Ret : Node_Id;
-
- begin
- if Is_Entity_Name (N)
- and then Present (Entity (N))
- then
- E := Entity (N);
-
- if Is_Formal (E)
- and then Scope (E) = Subp
- then
- A := Renamed_Object (E);
-
- -- Rewrite the occurrence of the formal into an occurrence of
- -- the actual. Also establish visibility on the proper view of
- -- the actual's subtype for the body's context (if the actual's
- -- subtype is private at the call point but its full view is
- -- visible to the body, then the inlined tree here must be
- -- analyzed with the full view).
-
- if Is_Entity_Name (A) then
- Rewrite (N, New_Occurrence_Of (Entity (A), Loc));
- Check_Private_View (N);
-
- elsif Nkind (A) = N_Defining_Identifier then
- Rewrite (N, New_Occurrence_Of (A, Loc));
- Check_Private_View (N);
-
- -- Numeric literal
-
- else
- Rewrite (N, New_Copy (A));
- end if;
- end if;
-
- return Skip;
-
- elsif Nkind (N) = N_Simple_Return_Statement then
- if No (Expression (N)) then
- Make_Exit_Label;
- Rewrite (N,
- Make_Goto_Statement (Loc,
- Name => New_Copy (Lab_Id)));
-
- else
- if Nkind (Parent (N)) = N_Handled_Sequence_Of_Statements
- and then Nkind (Parent (Parent (N))) = N_Subprogram_Body
- then
- -- Function body is a single expression. No need for
- -- exit label.
-
- null;
-
- else
- Num_Ret := Num_Ret + 1;
- Make_Exit_Label;
- end if;
-
- -- Because of the presence of private types, the views of the
- -- expression and the context may be different, so place an
- -- unchecked conversion to the context type to avoid spurious
- -- errors, e.g. when the expression is a numeric literal and
- -- the context is private. If the expression is an aggregate,
- -- use a qualified expression, because an aggregate is not a
- -- legal argument of a conversion.
-
- 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)));
- else
- Ret :=
- Unchecked_Convert_To
- (Ret_Type, Relocate_Node (Expression (N)));
- end if;
-
- if Nkind (Targ) = N_Defining_Identifier then
- Rewrite (N,
- Make_Assignment_Statement (Loc,
- Name => New_Occurrence_Of (Targ, Loc),
- Expression => Ret));
- else
- Rewrite (N,
- Make_Assignment_Statement (Loc,
- Name => New_Copy (Targ),
- Expression => Ret));
- end if;
-
- Set_Assignment_OK (Name (N));
-
- if Present (Exit_Lab) then
- Insert_After (N,
- Make_Goto_Statement (Loc,
- Name => New_Copy (Lab_Id)));
- end if;
- end if;
-
- return OK;
-
- -- Remove pragma Unreferenced since it may refer to formals that
- -- are not visible in the inlined body, and in any case we will
- -- not be posting warnings on the inlined body so it is unneeded.
-
- elsif Nkind (N) = N_Pragma
- and then Pragma_Name (N) = Name_Unreferenced
- then
- Rewrite (N, Make_Null_Statement (Sloc (N)));
- return OK;
-
- else
- return OK;
- end if;
- end Process_Formals;
-
- procedure Replace_Formals is new Traverse_Proc (Process_Formals);
-
- ------------------
- -- Process_Sloc --
- ------------------
-
- function Process_Sloc (Nod : Node_Id) return Traverse_Result is
- begin
- if not Debug_Generated_Code then
- Set_Sloc (Nod, Sloc (N));
- Set_Comes_From_Source (Nod, False);
- end if;
-
- return OK;
- end Process_Sloc;
-
- procedure Reset_Slocs is new Traverse_Proc (Process_Sloc);
-
- ---------------------------
- -- Rewrite_Function_Call --
- ---------------------------
-
- procedure Rewrite_Function_Call (N : Node_Id; Blk : Node_Id) is
- HSS : constant Node_Id := Handled_Statement_Sequence (Blk);
- Fst : constant Node_Id := First (Statements (HSS));
-
- begin
- -- Optimize simple case: function body is a single return statement,
- -- which has been expanded into an assignment.
-
- if Is_Empty_List (Declarations (Blk))
- 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.
-
- if Nkind (N) = N_Identifier
- and then Nkind (Parent (Entity (N))) = N_Object_Declaration
- then
- Rewrite (Parent (Entity (N)), Make_Null_Statement (Loc));
- end if;
-
- Rewrite (N, Expression (Fst));
-
- elsif Nkind (N) = N_Identifier
- and then Nkind (Parent (Entity (N))) = N_Object_Declaration
- then
- -- The block assigns the result of the call to the temporary
-
- Insert_After (Parent (Entity (N)), Blk);
-
- 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))))))
- then
- -- Replace assignment with the block
-
- declare
- Original_Assignment : constant Node_Id := Parent (N);
-
- begin
- -- Preserve the original assignment node to keep the complete
- -- assignment subtree consistent enough for Analyze_Assignment
- -- to proceed (specifically, the original Lhs node must still
- -- have an assignment statement as its parent).
-
- -- We cannot rely on Original_Node to go back from the block
- -- node to the assignment node, because the assignment might
- -- already be a rewrite substitution.
-
- Discard_Node (Relocate_Node (Original_Assignment));
- Rewrite (Original_Assignment, Blk);
- end;
-
- elsif Nkind (Parent (N)) = N_Object_Declaration then
- Set_Expression (Parent (N), Empty);
- Insert_After (Parent (N), Blk);
-
- elsif Is_Unc then
- Insert_Before (Parent (N), Blk);
- end if;
- end Rewrite_Function_Call;
-
- ----------------------------
- -- Rewrite_Procedure_Call --
- ----------------------------
-
- 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
- -- scope. For example, they need to have visibility on the constant
- -- declarations created for the formals.
-
- -- If N needs no transient scope, and if there are no declarations in
- -- the inlined body, we can do a little optimization and insert the
- -- statements for the body directly after N, and rewrite N to a
- -- null statement, instead of rewriting N into a full-blown block
- -- statement.
-
- if not Scope_Is_Transient
- and then Is_Empty_List (Declarations (Blk))
- then
- Insert_List_After (N, Statements (HSS));
- Rewrite (N, Make_Null_Statement (Loc));
- else
- Rewrite (N, Blk);
- end if;
- end Rewrite_Procedure_Call;
-
- -------------------------
- -- Formal_Is_Used_Once --
- -------------------------
-
- function Formal_Is_Used_Once (Formal : Entity_Id) return Boolean is
- Use_Counter : Int := 0;
-
- function Count_Uses (N : Node_Id) return Traverse_Result;
- -- Traverse the tree and count the uses of the formal parameter.
- -- In this case, for optimization purposes, we do not need to
- -- continue the traversal once more than one use is encountered.
-
- ----------------
- -- Count_Uses --
- ----------------
-
- function Count_Uses (N : Node_Id) return Traverse_Result is
- begin
- -- The original node is an identifier
-
- if Nkind (N) = N_Identifier
- and then Present (Entity (N))
-
- -- Original node's entity points to the one in the copied body
-
- and then Nkind (Entity (N)) = N_Identifier
- and then Present (Entity (Entity (N)))
-
- -- The entity of the copied node is the formal parameter
-
- and then Entity (Entity (N)) = Formal
- then
- Use_Counter := Use_Counter + 1;
-
- if Use_Counter > 1 then
-
- -- Denote more than one use and abandon the traversal
-
- Use_Counter := 2;
- return Abandon;
-
- end if;
- end if;
-
- return OK;
- end Count_Uses;
-
- procedure Count_Formal_Uses is new Traverse_Proc (Count_Uses);
-
- -- Start of processing for Formal_Is_Used_Once
-
- begin
- Count_Formal_Uses (Orig_Bod);
- return Use_Counter = 1;
- end Formal_Is_Used_Once;
-
- -- Start of processing for Expand_Inlined_Call
-
- begin
- -- Check for special case of To_Address call, and if so, just do an
- -- unchecked conversion instead of expanding the call. Not only is this
- -- more efficient, but it also avoids problem with order of elaboration
- -- when address clauses are inlined (address expression elaborated at
- -- wrong point).
-
- if Subp = RTE (RE_To_Address) then
- Rewrite (N,
- Unchecked_Convert_To
- (RTE (RE_Address),
- Relocate_Node (First_Actual (N))));
- return;
-
- elsif Is_Null_Procedure then
- Rewrite (N, Make_Null_Statement (Loc));
- return;
- end if;
-
- -- 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
- -- subprograms this must be done explicitly.
-
- if In_Open_Scopes (Subp) then
- Error_Msg_N ("call to recursive subprogram cannot be inlined?", N);
- Set_Is_Inlined (Subp, False);
- return;
- end if;
-
- if Nkind (Orig_Bod) = N_Defining_Identifier
- or else Nkind (Orig_Bod) = N_Defining_Operator_Symbol
- then
- -- Subprogram is a renaming_as_body. Calls appearing after the
- -- renaming can be replaced with calls to the renamed entity
- -- directly, because the subprograms are subtype conformant. If
- -- the renamed subprogram is an inherited operation, we must redo
- -- the expansion because implicit conversions may be needed.
-
- Set_Name (N, New_Occurrence_Of (Orig_Bod, Loc));
-
- if Present (Alias (Orig_Bod)) then
- Expand_Call (N);
- end if;
-
- return;
- end if;
-
- -- Use generic machinery to copy body of inlined subprogram, as if it
- -- were an instantiation, resetting source locations appropriately, so
- -- that nested inlined calls appear in the main unit.
-
- Save_Env (Subp, Empty);
- Set_Copied_Sloc_For_Inlined_Body (N, Defining_Entity (Orig_Bod));
-
- Bod := Copy_Generic_Node (Orig_Bod, Empty, Instantiating => True);
- Blk :=
- Make_Block_Statement (Loc,
- Declarations => Declarations (Bod),
- Handled_Statement_Sequence => Handled_Statement_Sequence (Bod));
-
- if No (Declarations (Bod)) then
- 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.
-
- if Is_Unc then
- Targ1 := Defining_Identifier (First (Declarations (Blk)));
- end if;
-
- -- If this is a derived function, establish the proper return type
-
- if Present (Orig_Subp)
- and then Orig_Subp /= Subp
- then
- Ret_Type := Etype (Orig_Subp);
- else
- Ret_Type := Etype (Subp);
- end if;
-
- -- Create temporaries for the actuals that are expressions, or that
- -- are scalars and require copying to preserve semantics.
-
- F := First_Formal (Subp);
- A := First_Actual (N);
- while Present (F) loop
- if Present (Renamed_Object (F)) then
- Error_Msg_N ("cannot inline call to recursive subprogram", N);
- return;
- end if;
-
- -- If the argument may be a controlling argument in a call within
- -- the inlined body, we must preserve its classwide nature to insure
- -- that dynamic dispatching take place subsequently. If the formal
- -- has a constraint it must be preserved to retain the semantics of
- -- the body.
-
- if Is_Class_Wide_Type (Etype (F))
- or else (Is_Access_Type (Etype (F))
- and then
- Is_Class_Wide_Type (Designated_Type (Etype (F))))
- then
- Temp_Typ := Etype (F);
-
- elsif Base_Type (Etype (F)) = Base_Type (Etype (A))
- and then Etype (F) /= Base_Type (Etype (F))
- then
- Temp_Typ := Etype (F);
-
- else
- Temp_Typ := Etype (A);
- end if;
-
- -- If the actual is a simple name or a literal, no need to
- -- create a temporary, object can be used directly.
-
- -- If the actual is a literal and the formal has its address taken,
- -- we cannot pass the literal itself as an argument, so its value
- -- must be captured in a temporary.
-
- if (Is_Entity_Name (A)
- and then
- (not Is_Scalar_Type (Etype (A))
- or else Ekind (Entity (A)) = E_Enumeration_Literal))
-
- -- When the actual is an identifier and the corresponding formal
- -- is used only once in the original body, the formal can be
- -- substituted directly with the actual parameter.
-
- or else (Nkind (A) = N_Identifier
- and then Formal_Is_Used_Once (F))
-
- or else
- (Nkind_In (A, N_Real_Literal,
- 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)));
- else
- Set_Renamed_Object (F, A);
- end if;
-
- else
- Temp :=
- Make_Defining_Identifier (Loc,
- Chars => New_Internal_Name ('C'));
-
- -- If the actual for an in/in-out parameter is a view conversion,
- -- make it into an unchecked conversion, given that an untagged
- -- type conversion is not a proper object for a renaming.
-
- -- In-out conversions that involve real conversions have already
- -- been transformed in Expand_Actuals.
-
- if Nkind (A) = N_Type_Conversion
- and then Ekind (F) /= E_In_Parameter
- then
- New_A :=
- Make_Unchecked_Type_Conversion (Loc,
- Subtype_Mark => New_Occurrence_Of (Etype (F), Loc),
- Expression => Relocate_Node (Expression (A)));
-
- elsif Etype (F) /= Etype (A) then
- New_A := Unchecked_Convert_To (Etype (F), Relocate_Node (A));
- Temp_Typ := Etype (F);
-
- else
- New_A := Relocate_Node (A);
- end if;
-
- Set_Sloc (New_A, Sloc (N));
-
- -- If the actual has a by-reference type, it cannot be copied, so
- -- its value is captured in a renaming declaration. Otherwise
- -- declare a local constant initialized with the actual.
-
- if Ekind (F) = E_In_Parameter
- and then not Is_Limited_Type (Etype (A))
- and then not Is_Tagged_Type (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);
- else
- Decl :=
- Make_Object_Renaming_Declaration (Loc,
- Defining_Identifier => Temp,
- Subtype_Mark => New_Occurrence_Of (Temp_Typ, Loc),
- Name => New_A);
- end if;
-
- Append (Decl, Decls);
- Set_Renamed_Object (F, Temp);
- end if;
-
- Next_Formal (F);
- Next_Actual (A);
- 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.
-
- if Ekind (Subp) = E_Function then
- if Nkind (Parent (N)) = N_Assignment_Statement
- and then Is_Entity_Name (Name (Parent (N)))
- then
- Targ := Name (Parent (N));
-
- elsif Nkind (Parent (N)) = N_Assignment_Statement
- and then Nkind (Name (Parent (N))) = N_Explicit_Dereference
- and then Is_Entity_Name (Prefix (Name (Parent (N))))
- then
- Targ := Name (Parent (N));
-
- else
- -- Replace call with temporary and create its declaration
-
- Temp :=
- Make_Defining_Identifier (Loc, New_Internal_Name ('C'));
- Set_Is_Internal (Temp);
-
- -- For the unconstrained case, the generated temporary has the
- -- same constrained declaration as the result variable.
- -- It may eventually be possible to remove that temporary and
- -- use the result variable directly.
-
- if Is_Unc then
- Decl :=
- Make_Object_Declaration (Loc,
- Defining_Identifier => Temp,
- Object_Definition =>
- New_Copy_Tree (Object_Definition (Parent (Targ1))));
-
- Replace_Formals (Decl);
-
- else
- Decl :=
- Make_Object_Declaration (Loc,
- Defining_Identifier => Temp,
- Object_Definition =>
- New_Occurrence_Of (Ret_Type, Loc));
-
- Set_Etype (Temp, Ret_Type);
- end if;
-
- Set_No_Initialization (Decl);
- Append (Decl, Decls);
- Rewrite (N, New_Occurrence_Of (Temp, Loc));
- Targ := Temp;
- end if;
- end if;
-
- Insert_Actions (N, Decls);
-
- -- Traverse the tree and replace formals with actuals or their thunks.
- -- Attach block to tree before analysis and rewriting.
-
- Replace_Formals (Blk);
- Set_Parent (Blk, N);
-
- if not Comes_From_Source (Subp)
- or else Is_Predef
- then
- Reset_Slocs (Blk);
- end if;
-
- if Present (Exit_Lab) then
-
- -- If the body was a single expression, the single return statement
- -- and the corresponding label are useless.
-
- if Num_Ret = 1
- and then
- Nkind (Last (Statements (Handled_Statement_Sequence (Blk)))) =
- N_Goto_Statement
- then
- Remove (Last (Statements (Handled_Statement_Sequence (Blk))));
- else
- Append (Lab_Decl, (Declarations (Blk)));
- Append (Exit_Lab, Statements (Handled_Statement_Sequence (Blk)));
- end if;
- end if;
-
- -- Analyze Blk with In_Inlined_Body set, to avoid spurious errors on
- -- conflicting private views that Gigi would ignore. If this is
- -- predefined unit, analyze with checks off, as is done in the non-
- -- inlined run-time units.
-
- declare
- I_Flag : constant Boolean := In_Inlined_Body;
-
- begin
- In_Inlined_Body := True;
-
- if Is_Predef then
- declare
- Style : constant Boolean := Style_Check;
- begin
- Style_Check := False;
- Analyze (Blk, Suppress => All_Checks);
- Style_Check := Style;
- end;
-
- else
- Analyze (Blk);
- end if;
-
- In_Inlined_Body := I_Flag;
- end;
-
- if Ekind (Subp) = E_Procedure then
- Rewrite_Procedure_Call (N, Blk);
- else
- Rewrite_Function_Call (N, Blk);
-
- -- For the unconstrained case, the replacement of the call has been
- -- made prior to the complete analysis of the generated declarations.
- -- Propagate the proper type now.
-
- if Is_Unc then
- if Nkind (N) = N_Identifier then
- Set_Etype (N, Etype (Entity (N)));
- else
- Set_Etype (N, Etype (Targ1));
- end if;
- end if;
- end if;
-
- Restore_Env;
-
- -- Cleanup mapping between formals and actuals for other expansions
-
- F := First_Formal (Subp);
- while Present (F) loop
- Set_Renamed_Object (F, Empty);
- Next_Formal (F);
- end loop;
- end Expand_Inlined_Call;
-
- ----------------------------
- -- Expand_N_Function_Call --
- ----------------------------
-
- procedure Expand_N_Function_Call (N : Node_Id) is
- begin
- Expand_Call (N);
-
- -- If the return value of a foreign compiled function is
- -- VAX Float then expand the return (adjusts the location
- -- of the return value on Alpha/VMS, noop everywhere else).
- -- Comes_From_Source intercepts recursive expansion.
-
- if Vax_Float (Etype (N))
- and then Nkind (N) = N_Function_Call
- and then Present (Name (N))
- and then Present (Entity (Name (N)))
- and then Has_Foreign_Convention (Entity (Name (N)))
- and then Comes_From_Source (Parent (N))
- then
- Expand_Vax_Foreign_Return (N);
- end if;
- end Expand_N_Function_Call;
-
- ---------------------------------------
- -- Expand_N_Procedure_Call_Statement --
- ---------------------------------------
-
- procedure Expand_N_Procedure_Call_Statement (N : Node_Id) is
- begin
- Expand_Call (N);
- end Expand_N_Procedure_Call_Statement;
-
- ------------------------------
- -- Expand_N_Subprogram_Body --
- ------------------------------
-
- -- Add poll call if ATC polling is enabled, unless the body will be
- -- inlined by the back-end.
-
- -- Add dummy push/pop label nodes at start and end to clear any local
- -- exception indications if local-exception-to-goto optimization active.
-
- -- Add return statement if last statement in body is not a return statement
- -- (this makes things easier on Gigi which does not want to have to handle
- -- a missing return).
-
- -- Add call to Activate_Tasks if body is a task activator
-
- -- Deal with possible detection of infinite recursion
-
- -- Eliminate body completely if convention stubbed
-
- -- Encode entity names within body, since we will not need to reference
- -- these entities any longer in the front end.
-
- -- Initialize scalar out parameters if Initialize/Normalize_Scalars
-
- -- Reset Pure indication if any parameter has root type System.Address
-
- -- Wrap thread body
-
- procedure Expand_N_Subprogram_Body (N : Node_Id) is
- Loc : constant Source_Ptr := Sloc (N);
- H : constant Node_Id := Handled_Statement_Sequence (N);
- Body_Id : Entity_Id;
- Except_H : Node_Id;
- L : List_Id;
- Spec_Id : Entity_Id;
-
- procedure Add_Return (S : List_Id);
- -- Append a return statement to the statement sequence S if the last
- -- statement is not already a return or a goto statement. Note that
- -- the latter test is not critical, it does not matter if we add a
- -- few extra returns, since they get eliminated anyway later on.
-
- ----------------
- -- Add_Return --
- ----------------
-
- procedure Add_Return (S : List_Id) is
- Last_Stm : Node_Id;
- Loc : Source_Ptr;
-
- begin
- -- Get last statement, ignoring any Pop_xxx_Label nodes, which are
- -- not relevant in this context since they are not executable.
-
- Last_Stm := Last (S);
- while Nkind (Last_Stm) in N_Pop_xxx_Label loop
- Prev (Last_Stm);
- end loop;
-
- -- Now insert return unless last statement is a transfer
-
- if not Is_Transfer (Last_Stm) then
-
- -- The source location for the return is the end label of the
- -- procedure if present. Otherwise use the sloc of the last
- -- statement in the list. If the list comes from a generated
- -- exception handler and we are not debugging generated code,
- -- all the statements within the handler are made invisible
- -- to the debugger.
-
- if Nkind (Parent (S)) = N_Exception_Handler
- and then not Comes_From_Source (Parent (S))
- then
- Loc := Sloc (Last_Stm);
-
- elsif Present (End_Label (H)) then
- Loc := Sloc (End_Label (H));
-
- else
- Loc := Sloc (Last_Stm);
- end if;
-
- Append_To (S, Make_Simple_Return_Statement (Loc));
- end if;
- end Add_Return;
-
- -- Start of processing for Expand_N_Subprogram_Body
-
- begin
- -- Set L to either the list of declarations if present, or
- -- to the list of statements if no declarations are present.
- -- This is used to insert new stuff at the start.
-
- if Is_Non_Empty_List (Declarations (N)) then
- L := Declarations (N);
- else
- L := Statements (H);
- end if;
-
- -- If local-exception-to-goto optimization active, insert dummy push
- -- statements at start, and dummy pop statements at end.
-
- if (Debug_Flag_Dot_G
- or else Restriction_Active (No_Exception_Propagation))
- and then Is_Non_Empty_List (L)
- then
- declare
- FS : constant Node_Id := First (L);
- FL : constant Source_Ptr := Sloc (FS);
- LS : Node_Id;
- LL : Source_Ptr;
-
- begin
- -- LS points to either last statement, if statements are present
- -- or to the last declaration if there are no statements present.
- -- It is the node after which the pop's are generated.
-
- if Is_Non_Empty_List (Statements (H)) then
- LS := Last (Statements (H));
- else
- LS := Last (L);
- end if;
-
- LL := Sloc (LS);
-
- Insert_List_Before_And_Analyze (FS, New_List (
- Make_Push_Constraint_Error_Label (FL),
- Make_Push_Program_Error_Label (FL),
- Make_Push_Storage_Error_Label (FL)));
-
- Insert_List_After_And_Analyze (LS, New_List (
- Make_Pop_Constraint_Error_Label (LL),
- Make_Pop_Program_Error_Label (LL),
- Make_Pop_Storage_Error_Label (LL)));
- end;
- end if;
-
- -- Find entity for subprogram
-
- Body_Id := Defining_Entity (N);
-
- if Present (Corresponding_Spec (N)) then
- Spec_Id := Corresponding_Spec (N);
- else
- Spec_Id := Body_Id;
- end if;
-
- -- Need poll on entry to subprogram if polling enabled. We only do this
- -- for non-empty subprograms, since it does not seem necessary to poll
- -- for a dummy null subprogram. Do not add polling point if calls to
- -- this subprogram will be inlined by the back-end, to avoid repeated
- -- polling points in nested inlinings.
-
- if Is_Non_Empty_List (L) then
- if Is_Inlined (Spec_Id)
- and then Front_End_Inlining
- and then Optimization_Level > 1
- then
- null;
- else
- Generate_Poll_Call (First (L));
- end if;
- end if;
-
- -- If this is a Pure function which has any parameters whose root
- -- type is System.Address, reset the Pure indication, since it will
- -- likely cause incorrect code to be generated as the parameter is
- -- probably a pointer, and the fact that the same pointer is passed
- -- does not mean that the same value is being referenced.
-
- -- Note that if the programmer gave an explicit Pure_Function pragma,
- -- then we believe the programmer, and leave the subprogram Pure.
-
- -- This code should probably be at the freeze point, so that it
- -- happens even on a -gnatc (or more importantly -gnatt) compile
- -- so that the semantic tree has Is_Pure set properly ???
-
- if Is_Pure (Spec_Id)
- and then Is_Subprogram (Spec_Id)
- and then not Has_Pragma_Pure_Function (Spec_Id)
- then
- declare
- F : Entity_Id;
-
- begin
- F := First_Formal (Spec_Id);
- while Present (F) loop
- if Is_Descendent_Of_Address (Etype (F)) then
- Set_Is_Pure (Spec_Id, False);
-
- if Spec_Id /= Body_Id then
- Set_Is_Pure (Body_Id, False);
- end if;
-
- exit;
- end if;
-
- Next_Formal (F);
- end loop;
- end;
- end if;
-
- -- Initialize any scalar OUT args if Initialize/Normalize_Scalars
-
- if Init_Or_Norm_Scalars and then Is_Subprogram (Spec_Id) then
- declare
- F : Entity_Id;
-
- begin
- -- Loop through formals
-
- F := First_Formal (Spec_Id);
- while Present (F) loop
- if Is_Scalar_Type (Etype (F))
- and then Ekind (F) = E_Out_Parameter
- then
- Check_Restriction (No_Default_Initialization, F);
-
- -- Insert the initialization. We turn off validity checks
- -- for this assignment, since we do not want any check on
- -- the initial value itself (which may well be invalid).
-
- Insert_Before_And_Analyze (First (L),
- Make_Assignment_Statement (Loc,
- Name => New_Occurrence_Of (F, Loc),
- Expression => Get_Simple_Init_Val (Etype (F), N)),
- Suppress => Validity_Check);
- end if;
-
- Next_Formal (F);
- end loop;
- end;
- end if;
-
- -- Clear out statement list for stubbed procedure
-
- if Present (Corresponding_Spec (N)) then
- Set_Elaboration_Flag (N, Spec_Id);
-
- if Convention (Spec_Id) = Convention_Stubbed
- or else Is_Eliminated (Spec_Id)
- then
- Set_Declarations (N, Empty_List);
- Set_Handled_Statement_Sequence (N,
- Make_Handled_Sequence_Of_Statements (Loc,
- Statements => New_List (
- Make_Null_Statement (Loc))));
- return;
- end if;
- end if;
-
- -- Create a set of discriminals for the next protected subprogram body
-
- if Is_List_Member (N)
- and then Present (Parent (List_Containing (N)))
- and then Nkind (Parent (List_Containing (N))) = N_Protected_Body
- and then Present (Next_Protected_Operation (N))
- then
- Set_Discriminals (Parent (Base_Type (Scope (Spec_Id))));
- end if;
-
- -- Returns_By_Ref flag is normally set when the subprogram is frozen
- -- but subprograms with no specs are not frozen.
-
- declare
- Typ : constant Entity_Id := Etype (Spec_Id);
- Utyp : constant Entity_Id := Underlying_Type (Typ);
-
- begin
- if not Acts_As_Spec (N)
- and then Nkind (Parent (Parent (Spec_Id))) /=
- N_Subprogram_Body_Stub
- then
- null;
-
- elsif Is_Inherently_Limited_Type (Typ) then
- Set_Returns_By_Ref (Spec_Id);
-
- elsif Present (Utyp) and then CW_Or_Has_Controlled_Part (Utyp) then
- Set_Returns_By_Ref (Spec_Id);
- end if;
- end;
-
- -- For a procedure, we add a return for all possible syntactic ends
- -- of the subprogram. Note that reanalysis is not necessary in this
- -- case since it would require a lot of work and accomplish nothing.
-
- if Ekind (Spec_Id) = E_Procedure
- or else Ekind (Spec_Id) = E_Generic_Procedure
- then
- Add_Return (Statements (H));
-
- if Present (Exception_Handlers (H)) then
- Except_H := First_Non_Pragma (Exception_Handlers (H));
- while Present (Except_H) loop
- Add_Return (Statements (Except_H));
- Next_Non_Pragma (Except_H);
- end loop;
- end if;
-
- -- For a function, we must deal with the case where there is at least
- -- one missing return. What we do is to wrap the entire body of the
- -- function in a block:
-
- -- begin
- -- ...
- -- end;
-
- -- becomes
-
- -- begin
- -- begin
- -- ...
- -- end;
-
- -- raise Program_Error;
- -- end;
-
- -- This approach is necessary because the raise must be signalled
- -- to the caller, not handled by any local handler (RM 6.4(11)).
-
- -- Note: we do not need to analyze the constructed sequence here,
- -- since it has no handler, and an attempt to analyze the handled
- -- statement sequence twice is risky in various ways (e.g. the
- -- issue of expanding cleanup actions twice).
-
- elsif Has_Missing_Return (Spec_Id) then
- declare
- Hloc : constant Source_Ptr := Sloc (H);
- Blok : constant Node_Id :=
- Make_Block_Statement (Hloc,
- Handled_Statement_Sequence => H);
- Rais : constant Node_Id :=
- Make_Raise_Program_Error (Hloc,
- Reason => PE_Missing_Return);
-
- begin
- Set_Handled_Statement_Sequence (N,
- Make_Handled_Sequence_Of_Statements (Hloc,
- Statements => New_List (Blok, Rais)));
-
- Push_Scope (Spec_Id);
- Analyze (Blok);
- Analyze (Rais);
- Pop_Scope;
- end;
- end if;
-
- -- If subprogram contains a parameterless recursive call, then we may
- -- have an infinite recursion, so see if we can generate code to check
- -- for this possibility if storage checks are not suppressed.
-
- if Ekind (Spec_Id) = E_Procedure
- and then Has_Recursive_Call (Spec_Id)
- and then not Storage_Checks_Suppressed (Spec_Id)
- then
- Detect_Infinite_Recursion (N, Spec_Id);
- end if;
-
- -- Set to encode entity names in package body before gigi is called
-
- Qualify_Entity_Names (N);
- end Expand_N_Subprogram_Body;
-
- -----------------------------------
- -- Expand_N_Subprogram_Body_Stub --
- -----------------------------------
-
- procedure Expand_N_Subprogram_Body_Stub (N : Node_Id) is
- begin
- if Present (Corresponding_Body (N)) then
- Expand_N_Subprogram_Body (
- Unit_Declaration_Node (Corresponding_Body (N)));
- end if;
- end Expand_N_Subprogram_Body_Stub;
-
- -------------------------------------
- -- Expand_N_Subprogram_Declaration --
- -------------------------------------
-
- -- If the declaration appears within a protected body, it is a private
- -- operation of the protected type. We must create the corresponding
- -- protected subprogram an associated formals. For a normal protected
- -- operation, this is done when expanding the protected type declaration.
-
- -- If the declaration is for a null procedure, emit null body
-
- procedure Expand_N_Subprogram_Declaration (N : Node_Id) is
- Loc : constant Source_Ptr := Sloc (N);
- Subp : constant Entity_Id := Defining_Entity (N);
- Scop : constant Entity_Id := Scope (Subp);
- Prot_Decl : Node_Id;
- Prot_Bod : Node_Id;
- Prot_Id : Entity_Id;
-
- begin
- -- Deal with case of protected subprogram. Do not generate protected
- -- operation if operation is flagged as eliminated.
-
- if Is_List_Member (N)
- and then Present (Parent (List_Containing (N)))
- and then Nkind (Parent (List_Containing (N))) = N_Protected_Body
- and then Is_Protected_Type (Scop)
- then
- if No (Protected_Body_Subprogram (Subp))
- and then not Is_Eliminated (Subp)
- then
- Prot_Decl :=
- Make_Subprogram_Declaration (Loc,
- Specification =>
- Build_Protected_Sub_Specification
- (N, Scop, Unprotected_Mode));
-
- -- The protected subprogram is declared outside of the protected
- -- body. Given that the body has frozen all entities so far, we
- -- analyze the subprogram and perform freezing actions explicitly.
- -- including the generation of an explicit freeze node, to ensure
- -- that gigi has the proper order of elaboration.
- -- If the body is a subunit, the insertion point is before the
- -- stub in the parent.
-
- Prot_Bod := Parent (List_Containing (N));
-
- if Nkind (Parent (Prot_Bod)) = N_Subunit then
- Prot_Bod := Corresponding_Stub (Parent (Prot_Bod));
- end if;
-
- Insert_Before (Prot_Bod, Prot_Decl);
- Prot_Id := Defining_Unit_Name (Specification (Prot_Decl));
- Set_Has_Delayed_Freeze (Prot_Id);
-
- Push_Scope (Scope (Scop));
- Analyze (Prot_Decl);
- Insert_Actions (N, Freeze_Entity (Prot_Id, Loc));
- Set_Protected_Body_Subprogram (Subp, Prot_Id);
- Pop_Scope;
- end if;
-
- -- Ada 2005 (AI-348): Generation of the null body
-
- elsif Nkind (Specification (N)) = N_Procedure_Specification
- and then Null_Present (Specification (N))
- then
- declare
- Bod : constant Node_Id :=
- Make_Subprogram_Body (Loc,
- Specification =>
- New_Copy_Tree (Specification (N)),
- Declarations => New_List,
- Handled_Statement_Sequence =>
- Make_Handled_Sequence_Of_Statements (Loc,
- Statements => New_List (Make_Null_Statement (Loc))));
- begin
- Set_Body_To_Inline (N, Bod);
- Insert_After (N, Bod);
- Analyze (Bod);
-
- -- Corresponding_Spec isn't being set by Analyze_Subprogram_Body,
- -- evidently because Set_Has_Completion is called earlier for null
- -- procedures in Analyze_Subprogram_Declaration, so we force its
- -- setting here. If the setting of Has_Completion is not set
- -- earlier, then it can result in missing body errors if other
- -- errors were already reported (since expansion is turned off).
-
- -- Should creation of the empty body be moved to the analyzer???
-
- Set_Corresponding_Spec (Bod, Defining_Entity (Specification (N)));
- end;
- end if;
- end Expand_N_Subprogram_Declaration;
-
- ---------------------------------------
- -- Expand_Protected_Object_Reference --
- ---------------------------------------
-
- function Expand_Protected_Object_Reference
- (N : Node_Id;
- Scop : Entity_Id) return Node_Id
- is
- Loc : constant Source_Ptr := Sloc (N);
- Corr : Entity_Id;
- Rec : Node_Id;
- Param : Entity_Id;
- Proc : Entity_Id;
-
- begin
- Rec :=
- Make_Identifier (Loc,
- Chars => Name_uObject);
- Set_Etype (Rec, Corresponding_Record_Type (Scop));
-
- -- Find enclosing protected operation, and retrieve its first parameter,
- -- which denotes the enclosing protected object. If the enclosing
- -- operation is an entry, we are immediately within the protected body,
- -- and we can retrieve the object from the service entries procedure. A
- -- barrier function has the same signature as an entry. A barrier
- -- function is compiled within the protected object, but unlike
- -- protected operations its never needs locks, so that its protected
- -- body subprogram points to itself.
-
- Proc := Current_Scope;
- while Present (Proc)
- and then Scope (Proc) /= Scop
- loop
- Proc := Scope (Proc);
- end loop;
-
- Corr := Protected_Body_Subprogram (Proc);
-
- if No (Corr) then
-
- -- Previous error left expansion incomplete.
- -- Nothing to do on this call.
-
- return Empty;
- end if;
-
- Param :=
- Defining_Identifier
- (First (Parameter_Specifications (Parent (Corr))));
-
- if Is_Subprogram (Proc)
- and then Proc /= Corr
- then
- -- Protected function or procedure
-
- Set_Entity (Rec, Param);
-
- -- Rec is a reference to an entity which will not be in scope when
- -- the call is reanalyzed, and needs no further analysis.
-
- Set_Analyzed (Rec);
-
- else
- -- Entry or barrier function for entry body. The first parameter of
- -- the entry body procedure is pointer to the object. We create a
- -- local variable of the proper type, duplicating what is done to
- -- define _object later on.
-
- declare
- Decls : List_Id;
- Obj_Ptr : constant Entity_Id := Make_Defining_Identifier (Loc,
- Chars =>
- New_Internal_Name ('T'));
-
- begin
- Decls := New_List (
- Make_Full_Type_Declaration (Loc,
- Defining_Identifier => Obj_Ptr,
- Type_Definition =>
- Make_Access_To_Object_Definition (Loc,
- Subtype_Indication =>
- New_Reference_To
- (Corresponding_Record_Type (Scop), Loc))));
-
- Insert_Actions (N, Decls);
- Insert_Actions (N, Freeze_Entity (Obj_Ptr, Sloc (N)));
-
- Rec :=
- Make_Explicit_Dereference (Loc,
- Unchecked_Convert_To (Obj_Ptr,
- New_Occurrence_Of (Param, Loc)));
-
- -- Analyze new actual. Other actuals in calls are already analyzed
- -- and the list of actuals is not reanalyzed after rewriting.
-
- Set_Parent (Rec, N);
- Analyze (Rec);
- end;
- end if;
-
- return Rec;
- end Expand_Protected_Object_Reference;
-
- --------------------------------------
- -- Expand_Protected_Subprogram_Call --
- --------------------------------------
-
- procedure Expand_Protected_Subprogram_Call
- (N : Node_Id;
- Subp : Entity_Id;
- Scop : Entity_Id)
- is
- 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 not In_Open_Scopes (Scop)
- or else not Is_Entity_Name (Name (N))
- then
- if Nkind (Name (N)) = N_Selected_Component then
- Rec := Prefix (Name (N));
-
- else
- pragma Assert (Nkind (Name (N)) = N_Indexed_Component);
- Rec := Prefix (Prefix (Name (N)));
- end if;
-
- Build_Protected_Subprogram_Call (N,
- Name => New_Occurrence_Of (Subp, Sloc (N)),
- Rec => Convert_Concurrent (Rec, Etype (Rec)),
- External => True);
-
- else
- Rec := Expand_Protected_Object_Reference (N, Scop);
-
- if No (Rec) then
- return;
- end if;
-
- Build_Protected_Subprogram_Call (N,
- Name => Name (N),
- Rec => Rec,
- External => False);
-
- end if;
-
- Analyze (N);
-
- -- If it is a function call it can appear in elaboration code and
- -- the called entity must be frozen here.
-
- if Ekind (Subp) = E_Function then
- Freeze_Expression (Name (N));
- end if;
- end Expand_Protected_Subprogram_Call;
-
- --------------------------------
- -- Is_Build_In_Place_Function --
- --------------------------------
-
- function Is_Build_In_Place_Function (E : Entity_Id) return Boolean is
- begin
- -- For now we test whether E denotes a function or access-to-function
- -- type whose result subtype is inherently limited. Later this test may
- -- be revised to allow composite nonlimited types. Functions with a
- -- foreign convention or whose result type has a foreign convention
- -- never qualify.
-
- if Ekind (E) = E_Function
- or else Ekind (E) = E_Generic_Function
- or else (Ekind (E) = E_Subprogram_Type
- and then Etype (E) /= Standard_Void_Type)
- then
- -- Note: If you have Convention (C) on an inherently limited type,
- -- you're on your own. That is, the C code will have to be carefully
- -- written to know about the Ada conventions.
-
- if Has_Foreign_Convention (E)
- or else Has_Foreign_Convention (Etype (E))
- then
- return False;
-
- -- If the return type is a limited interface it has to be treated
- -- as a return in place, even if the actual object is some non-
- -- limited descendant.
-
- elsif Is_Limited_Interface (Etype (E)) then
- return True;
-
- else
- return Is_Inherently_Limited_Type (Etype (E))
- and then Ada_Version >= Ada_05
- and then not Debug_Flag_Dot_L;
- end if;
-
- else
- return False;
- end if;
- end Is_Build_In_Place_Function;
-
- -------------------------------------
- -- Is_Build_In_Place_Function_Call --
- -------------------------------------
-
- function Is_Build_In_Place_Function_Call (N : Node_Id) return Boolean is
- Exp_Node : Node_Id := N;
- Function_Id : Entity_Id;
-
- begin
- -- 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)
- then
- Exp_Node := Expression (N);
- end if;
-
- if Nkind (Exp_Node) /= N_Function_Call then
- return False;
-
- else
- if Is_Entity_Name (Name (Exp_Node)) then
- Function_Id := Entity (Name (Exp_Node));
-
- elsif Nkind (Name (Exp_Node)) = N_Explicit_Dereference then
- Function_Id := Etype (Name (Exp_Node));
- end if;
-
- return Is_Build_In_Place_Function (Function_Id);
- end if;
- end Is_Build_In_Place_Function_Call;
-
- ---------------------------------------
- -- Is_Build_In_Place_Function_Return --
- ---------------------------------------
-
- function Is_Build_In_Place_Function_Return (N : Node_Id) return Boolean is
- begin
- if Nkind_In (N, N_Simple_Return_Statement,
- N_Extended_Return_Statement)
- then
- return Is_Build_In_Place_Function
- (Return_Applies_To (Return_Statement_Entity (N)));
- else
- return False;
- end if;
- end Is_Build_In_Place_Function_Return;
-
- -----------------------
- -- Freeze_Subprogram --
- -----------------------
-
- procedure Freeze_Subprogram (N : Node_Id) is
- Loc : constant Source_Ptr := Sloc (N);
-
- procedure Register_Predefined_DT_Entry (Prim : Entity_Id);
- -- (Ada 2005): Register a predefined primitive in all the secondary
- -- dispatch tables of its primitive type.
-
- ----------------------------------
- -- Register_Predefined_DT_Entry --
- ----------------------------------
-
- procedure Register_Predefined_DT_Entry (Prim : Entity_Id) is
- Iface_DT_Ptr : Elmt_Id;
- Tagged_Typ : Entity_Id;
- Thunk_Id : Entity_Id;
- Thunk_Code : Node_Id;
-
- begin
- Tagged_Typ := Find_Dispatching_Type (Prim);
-
- if No (Access_Disp_Table (Tagged_Typ))
- or else not Has_Interfaces (Tagged_Typ)
- or else not RTE_Available (RE_Interface_Tag)
- or else Restriction_Active (No_Dispatching_Calls)
- then
- return;
- end if;
-
- -- Skip the first two access-to-dispatch-table pointers since they
- -- leads to the primary dispatch table (predefined DT and user
- -- defined DT). We are only concerned with the secondary dispatch
- -- table pointers. Note that the access-to- dispatch-table pointer
- -- corresponds to the first implemented interface retrieved below.
-
- Iface_DT_Ptr :=
- Next_Elmt (Next_Elmt (First_Elmt (Access_Disp_Table (Tagged_Typ))));
-
- while Present (Iface_DT_Ptr)
- and then Ekind (Node (Iface_DT_Ptr)) = E_Constant
- loop
- pragma Assert (Has_Thunks (Node (Iface_DT_Ptr)));
- Expand_Interface_Thunk (Prim, Thunk_Id, Thunk_Code);
-
- if Present (Thunk_Code) then
- Insert_Actions_After (N, New_List (
- Thunk_Code,
-
- Build_Set_Predefined_Prim_Op_Address (Loc,
- Tag_Node =>
- New_Reference_To (Node (Next_Elmt (Iface_DT_Ptr)), Loc),
- Position => DT_Position (Prim),
- Address_Node =>
- Unchecked_Convert_To (RTE (RE_Prim_Ptr),
- Make_Attribute_Reference (Loc,
- Prefix => New_Reference_To (Thunk_Id, Loc),
- Attribute_Name => Name_Unrestricted_Access))),
-
- Build_Set_Predefined_Prim_Op_Address (Loc,
- Tag_Node =>
- New_Reference_To
- (Node (Next_Elmt (Next_Elmt (Next_Elmt (Iface_DT_Ptr)))),
- Loc),
- Position => DT_Position (Prim),
- Address_Node =>
- Unchecked_Convert_To (RTE (RE_Prim_Ptr),
- Make_Attribute_Reference (Loc,
- Prefix => New_Reference_To (Prim, Loc),
- Attribute_Name => Name_Unrestricted_Access)))));
- end if;
-
- -- Skip the tag of the predefined primitives dispatch table
-
- Next_Elmt (Iface_DT_Ptr);
- pragma Assert (Has_Thunks (Node (Iface_DT_Ptr)));
-
- -- Skip the 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
-
- Next_Elmt (Iface_DT_Ptr);
- pragma Assert (not Has_Thunks (Node (Iface_DT_Ptr)));
-
- Next_Elmt (Iface_DT_Ptr);
- end loop;
- end Register_Predefined_DT_Entry;
-
- -- Local variables
-
- Subp : constant Entity_Id := Entity (N);
-
- -- Start of processing for Freeze_Subprogram
-
- begin
- -- We suppress the initialization of the dispatch table entry when
- -- VM_Target because the dispatching mechanism is handled internally
- -- by the VM.
-
- if Is_Dispatching_Operation (Subp)
- and then not Is_Abstract_Subprogram (Subp)
- and then Present (DTC_Entity (Subp))
- and then Present (Scope (DTC_Entity (Subp)))
- and then VM_Target = No_VM
- and then not Restriction_Active (No_Dispatching_Calls)
- and then RTE_Available (RE_Tag)
- then
- declare
- Typ : constant Entity_Id := Scope (DTC_Entity (Subp));
-
- begin
- -- Handle private overridden primitives
-
- if not Is_CPP_Class (Typ) then
- Check_Overriding_Operation (Subp);
- end if;
-
- -- We assume that imported CPP primitives correspond with objects
- -- whose constructor is in the CPP side; therefore we don't need
- -- to generate code to register them in the dispatch table.
-
- if Is_CPP_Class (Typ) then
- null;
-
- -- Handle CPP primitives found in derivations of CPP_Class types.
- -- These primitives must have been inherited from some parent, and
- -- there is no need to register them in the dispatch table because
- -- Build_Inherit_Prims takes care of the initialization of these
- -- slots.
-
- elsif Is_Imported (Subp)
- and then (Convention (Subp) = Convention_CPP
- or else Convention (Subp) = Convention_C)
- then
- null;
-
- -- Generate code to register the primitive in non statically
- -- allocated dispatch tables
-
- elsif not Static_Dispatch_Tables
- or else not
- Is_Library_Level_Tagged_Type (Scope (DTC_Entity (Subp)))
- then
- -- When a primitive is frozen, enter its name in its dispatch
- -- table slot.
-
- if not Is_Interface (Typ)
- or else Present (Interface_Alias (Subp))
- then
- if Is_Predefined_Dispatching_Operation (Subp) then
- Register_Predefined_DT_Entry (Subp);
- end if;
-
- Register_Primitive (Loc,
- Prim => Subp,
- Ins_Nod => N);
- end if;
- end if;
- end;
- end if;
-
- -- Mark functions that return by reference. Note that it cannot be part
- -- of the normal semantic analysis of the spec since the underlying
- -- returned type may not be known yet (for private types).
-
- declare
- Typ : constant Entity_Id := Etype (Subp);
- Utyp : constant Entity_Id := Underlying_Type (Typ);
- begin
- if Is_Inherently_Limited_Type (Typ) then
- Set_Returns_By_Ref (Subp);
- elsif Present (Utyp) and then CW_Or_Has_Controlled_Part (Utyp) then
- Set_Returns_By_Ref (Subp);
- end if;
- end;
- end Freeze_Subprogram;
-
- -------------------------------------------
- -- Make_Build_In_Place_Call_In_Allocator --
- -------------------------------------------
-
- procedure Make_Build_In_Place_Call_In_Allocator
- (Allocator : Node_Id;
- Function_Call : Node_Id)
- is
- 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;
-
- begin
- -- Step past qualification or unchecked conversion (the latter can occur
- -- in cases of calls to 'Input).
-
- if Nkind_In (Func_Call,
- N_Qualified_Expression,
- N_Unchecked_Type_Conversion)
- then
- Func_Call := Expression (Func_Call);
- end if;
-
- -- If the call has already been processed to add build-in-place actuals
- -- then return. This should not normally occur in an allocator context,
- -- but we add the protection as a defensive measure.
-
- if Is_Expanded_Build_In_Place_Call (Func_Call) then
- return;
- end if;
-
- -- Mark the call as processed as a build-in-place call
-
- Set_Is_Expanded_Build_In_Place_Call (Func_Call);
-
- Loc := Sloc (Function_Call);
-
- if Is_Entity_Name (Name (Func_Call)) then
- Function_Id := Entity (Name (Func_Call));
-
- elsif Nkind (Name (Func_Call)) = N_Explicit_Dereference then
- Function_Id := Etype (Name (Func_Call));
-
- else
- raise Program_Error;
- end if;
-
- Result_Subt := Etype (Function_Id);
-
- -- When the result subtype is constrained, the return object must be
- -- allocated on the caller side, and access to it is passed to the
- -- function.
-
- -- Here and in related routines, we must examine the full view of the
- -- type, because the view at the point of call may differ from that
- -- that in the function body, and the expansion mechanism depends on
- -- the characteristics of the full view.
-
- if Is_Constrained (Underlying_Type (Result_Subt)) then
-
- -- Replace the initialized allocator of form "new T'(Func (...))"
- -- with an uninitialized allocator of form "new T", where T is the
- -- result subtype of the called function. The call to the function
- -- is handled separately further below.
-
- New_Allocator :=
- Make_Allocator (Loc, New_Reference_To (Result_Subt, Loc));
-
- Set_Storage_Pool (New_Allocator, Storage_Pool (Allocator));
- Set_Procedure_To_Call (New_Allocator, Procedure_To_Call (Allocator));
- Set_No_Initialization (New_Allocator);
-
- Rewrite (Allocator, New_Allocator);
-
- -- Create a new access object and initialize it to the result of the
- -- new uninitialized allocator.
-
- Return_Obj_Access :=
- Make_Defining_Identifier (Loc, New_Internal_Name ('R'));
- Set_Etype (Return_Obj_Access, Acc_Type);
-
- Insert_Action (Allocator,
- Make_Object_Declaration (Loc,
- Defining_Identifier => Return_Obj_Access,
- Object_Definition => New_Reference_To (Acc_Type, Loc),
- Expression => Relocate_Node (Allocator)));
-
- -- 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);
-
- Add_Final_List_Actual_To_Build_In_Place_Call
- (Func_Call, Function_Id, Acc_Type);
-
- Add_Task_Actuals_To_Build_In_Place_Call
- (Func_Call, Function_Id, Master_Actual => Master_Id (Acc_Type));
-
- -- Add an implicit actual to the function call that provides access
- -- to the allocated object. An unchecked conversion to the (specific)
- -- result subtype of the function is inserted to handle cases where
- -- the access type of the allocator has a class-wide designated type.
-
- Add_Access_Actual_To_Build_In_Place_Call
- (Func_Call,
- Function_Id,
- Make_Unchecked_Type_Conversion (Loc,
- Subtype_Mark => New_Reference_To (Result_Subt, Loc),
- Expression =>
- Make_Explicit_Dereference (Loc,
- Prefix => New_Reference_To (Return_Obj_Access, Loc))));
-
- -- When the result subtype is unconstrained, the function itself must
- -- perform the allocation of the return object, so we pass parameters
- -- indicating that. We don't yet handle the case where the allocation
- -- must be done in a user-defined storage pool, which will require
- -- passing another actual or two to provide allocation/deallocation
- -- operations. ???
-
- else
-
- -- 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);
-
- Add_Final_List_Actual_To_Build_In_Place_Call
- (Func_Call, Function_Id, Acc_Type);
-
- Add_Task_Actuals_To_Build_In_Place_Call
- (Func_Call, Function_Id, Master_Actual => Master_Id (Acc_Type));
-
- -- The caller does not provide the return object in this case, so we
- -- have to pass null for the object access actual.
-
- Add_Access_Actual_To_Build_In_Place_Call
- (Func_Call, Function_Id, Return_Object => Empty);
- end if;
-
- -- Finally, replace the allocator node with a reference to the result
- -- of the function call itself (which will effectively be an access
- -- to the object created by the allocator).
-
- Rewrite (Allocator, Make_Reference (Loc, Relocate_Node (Function_Call)));
- Analyze_And_Resolve (Allocator, Acc_Type);
- end Make_Build_In_Place_Call_In_Allocator;
-
- ---------------------------------------------------
- -- Make_Build_In_Place_Call_In_Anonymous_Context --
- ---------------------------------------------------
-
- procedure Make_Build_In_Place_Call_In_Anonymous_Context
- (Function_Call : Node_Id)
- is
- Loc : Source_Ptr;
- Func_Call : Node_Id := Function_Call;
- Function_Id : Entity_Id;
- Result_Subt : Entity_Id;
- Return_Obj_Id : Entity_Id;
- Return_Obj_Decl : Entity_Id;
-
- begin
- -- Step past qualification or unchecked conversion (the latter can occur
- -- in cases of calls to 'Input).
-
- if Nkind_In (Func_Call, N_Qualified_Expression,
- N_Unchecked_Type_Conversion)
- then
- Func_Call := Expression (Func_Call);
- end if;
-
- -- If the call has already been processed to add build-in-place actuals
- -- then return. One place this can occur is for calls to build-in-place
- -- functions that occur within a call to a protected operation, where
- -- due to rewriting and expansion of the protected call there can be
- -- more than one call to Expand_Actuals for the same set of actuals.
-
- if Is_Expanded_Build_In_Place_Call (Func_Call) then
- return;
- end if;
-
- -- Mark the call as processed as a build-in-place call
-
- Set_Is_Expanded_Build_In_Place_Call (Func_Call);
-
- Loc := Sloc (Function_Call);
-
- if Is_Entity_Name (Name (Func_Call)) then
- Function_Id := Entity (Name (Func_Call));
-
- elsif Nkind (Name (Func_Call)) = N_Explicit_Dereference then
- Function_Id := Etype (Name (Func_Call));
-
- else
- raise Program_Error;
- end if;
-
- Result_Subt := Etype (Function_Id);
-
- -- When the result subtype is constrained, an object of the subtype is
- -- declared and an access value designating it is passed as an actual.
-
- if Is_Constrained (Underlying_Type (Result_Subt)) then
-
- -- Create a temporary object to hold the function result
-
- Return_Obj_Id :=
- Make_Defining_Identifier (Loc,
- Chars => New_Internal_Name ('R'));
- Set_Etype (Return_Obj_Id, Result_Subt);
-
- Return_Obj_Decl :=
- Make_Object_Declaration (Loc,
- Defining_Identifier => Return_Obj_Id,
- Aliased_Present => True,
- Object_Definition => New_Reference_To (Result_Subt, Loc));
-
- Set_No_Initialization (Return_Obj_Decl);
-
- Insert_Action (Func_Call, Return_Obj_Decl);
-
- -- 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);
-
- Add_Final_List_Actual_To_Build_In_Place_Call
- (Func_Call, Function_Id, Acc_Type => Empty);
-
- Add_Task_Actuals_To_Build_In_Place_Call
- (Func_Call, Function_Id, Make_Identifier (Loc, Name_uMaster));
-
- -- Add an implicit actual to the function call that provides access
- -- to the caller's return object.
-
- Add_Access_Actual_To_Build_In_Place_Call
- (Func_Call, Function_Id, New_Reference_To (Return_Obj_Id, Loc));
-
- -- When the result subtype is unconstrained, the function must allocate
- -- the return object in the secondary stack, so appropriate implicit
- -- parameters are added to the call to indicate that. A transient
- -- scope is established to ensure eventual cleanup of the result.
-
- else
-
- -- 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
- (Func_Call, Function_Id, Alloc_Form => Secondary_Stack);
-
- Add_Final_List_Actual_To_Build_In_Place_Call
- (Func_Call, Function_Id, Acc_Type => Empty);
-
- Add_Task_Actuals_To_Build_In_Place_Call
- (Func_Call, Function_Id, Make_Identifier (Loc, Name_uMaster));
-
- -- Pass a null value to the function since no return object is
- -- available on the caller side.
-
- Add_Access_Actual_To_Build_In_Place_Call
- (Func_Call, Function_Id, Empty);
-
- Establish_Transient_Scope (Func_Call, Sec_Stack => True);
- end if;
- end Make_Build_In_Place_Call_In_Anonymous_Context;
-
- --------------------------------------------
- -- Make_Build_In_Place_Call_In_Assignment --
- --------------------------------------------
-
- procedure Make_Build_In_Place_Call_In_Assignment
- (Assign : Node_Id;
- Function_Call : Node_Id)
- is
- Lhs : constant Node_Id := Name (Assign);
- Loc : Source_Ptr;
- Func_Call : Node_Id := Function_Call;
- Function_Id : Entity_Id;
- Result_Subt : Entity_Id;
- Ref_Type : Entity_Id;
- Ptr_Typ_Decl : Node_Id;
- Def_Id : Entity_Id;
- New_Expr : Node_Id;
-
- begin
- -- Step past qualification or unchecked conversion (the latter can occur
- -- in cases of calls to 'Input).
-
- if Nkind_In (Func_Call, N_Qualified_Expression,
- N_Unchecked_Type_Conversion)
- then
- Func_Call := Expression (Func_Call);
- end if;
-
- -- If the call has already been processed to add build-in-place actuals
- -- then return. This should not normally occur in an assignment context,
- -- but we add the protection as a defensive measure.
-
- if Is_Expanded_Build_In_Place_Call (Func_Call) then
- return;
- end if;
-
- -- Mark the call as processed as a build-in-place call
-
- Set_Is_Expanded_Build_In_Place_Call (Func_Call);
-
- Loc := Sloc (Function_Call);
-
- if Is_Entity_Name (Name (Func_Call)) then
- Function_Id := Entity (Name (Func_Call));
-
- elsif Nkind (Name (Func_Call)) = N_Explicit_Dereference then
- Function_Id := Etype (Name (Func_Call));
-
- else
- raise Program_Error;
- end if;
-
- Result_Subt := Etype (Function_Id);
-
- -- When the result subtype is unconstrained, an additional actual must
- -- be passed to indicate that the caller is providing the return object.
- -- This parameter must also be passed when the called function has a
- -- 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
- (Func_Call, Function_Id, Alloc_Form => Caller_Allocation);
-
- -- If Lhs is a selected component, then pass it along so that its prefix
- -- object will be used as the source of the finalization list.
-
- if Nkind (Lhs) = N_Selected_Component then
- Add_Final_List_Actual_To_Build_In_Place_Call
- (Func_Call, Function_Id, Acc_Type => Empty, Sel_Comp => Lhs);
- else
- Add_Final_List_Actual_To_Build_In_Place_Call
- (Func_Call, Function_Id, Acc_Type => Empty);
- end if;
-
- Add_Task_Actuals_To_Build_In_Place_Call
- (Func_Call, Function_Id, Make_Identifier (Loc, Name_uMaster));
-
- -- Add an implicit actual to the function call that provides access to
- -- the caller's return object.
-
- Add_Access_Actual_To_Build_In_Place_Call
- (Func_Call,
- Function_Id,
- Make_Unchecked_Type_Conversion (Loc,
- Subtype_Mark => New_Reference_To (Result_Subt, Loc),
- Expression => Relocate_Node (Lhs)));
-
- -- Create an access type designating the function's result subtype
-
- Ref_Type :=
- Make_Defining_Identifier (Loc, New_Internal_Name ('A'));
-
- Ptr_Typ_Decl :=
- Make_Full_Type_Declaration (Loc,
- Defining_Identifier => Ref_Type,
- Type_Definition =>
- Make_Access_To_Object_Definition (Loc,
- All_Present => True,
- Subtype_Indication =>
- New_Reference_To (Result_Subt, Loc)));
-
- Insert_After_And_Analyze (Assign, Ptr_Typ_Decl);
-
- -- Finally, create an access object initialized to a reference to the
- -- function call.
-
- Def_Id :=
- Make_Defining_Identifier (Loc,
- Chars => New_Internal_Name ('R'));
- Set_Etype (Def_Id, Ref_Type);
-
- New_Expr :=
- Make_Reference (Loc,
- Prefix => Relocate_Node (Func_Call));
-
- Insert_After_And_Analyze (Ptr_Typ_Decl,
- Make_Object_Declaration (Loc,
- Defining_Identifier => Def_Id,
- Object_Definition => New_Reference_To (Ref_Type, Loc),
- Expression => New_Expr));
-
- Rewrite (Assign, Make_Null_Statement (Loc));
- end Make_Build_In_Place_Call_In_Assignment;
-
- ----------------------------------------------------
- -- Make_Build_In_Place_Call_In_Object_Declaration --
- ----------------------------------------------------
-
- procedure Make_Build_In_Place_Call_In_Object_Declaration
- (Object_Decl : Node_Id;
- Function_Call : Node_Id)
- is
- Loc : Source_Ptr;
- Obj_Def_Id : constant Entity_Id :=
- Defining_Identifier (Object_Decl);
-
- 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;
- Ptr_Typ_Decl : Node_Id;
- Def_Id : Entity_Id;
- New_Expr : Node_Id;
- Enclosing_Func : Entity_Id;
- Pass_Caller_Acc : Boolean := False;
-
- begin
- -- Step past qualification or unchecked conversion (the latter can occur
- -- in cases of calls to 'Input).
-
- if Nkind_In (Func_Call, N_Qualified_Expression,
- N_Unchecked_Type_Conversion)
- then
- Func_Call := Expression (Func_Call);
- end if;
-
- -- If the call has already been processed to add build-in-place actuals
- -- then return. This should not normally occur in an object declaration,
- -- but we add the protection as a defensive measure.
-
- if Is_Expanded_Build_In_Place_Call (Func_Call) then
- return;
- end if;
-
- -- Mark the call as processed as a build-in-place call
-
- Set_Is_Expanded_Build_In_Place_Call (Func_Call);
-
- Loc := Sloc (Function_Call);
-
- if Is_Entity_Name (Name (Func_Call)) then
- Function_Id := Entity (Name (Func_Call));
-
- elsif Nkind (Name (Func_Call)) = N_Explicit_Dereference then
- Function_Id := Etype (Name (Func_Call));
-
- else
- raise Program_Error;
- end if;
-
- 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.
-
- elsif Nkind (Parent (Object_Decl)) = N_Extended_Return_Statement then
- Pass_Caller_Acc := True;
-
- Enclosing_Func := Enclosing_Subprogram (Obj_Def_Id);
-
- -- If the enclosing function has a constrained result type, then
- -- caller allocation will be used.
-
- if Is_Constrained (Etype (Enclosing_Func)) then
- Add_Alloc_Form_Actual_To_Build_In_Place_Call
- (Func_Call, Function_Id, Alloc_Form => Caller_Allocation);
-
- -- 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
- Add_Alloc_Form_Actual_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));
- end if;
-
- -- Retrieve the BIPacc formal from the enclosing function and convert
- -- it to the access type of the callee's BIP_Object_Access formal.
-
- Caller_Object :=
- Make_Unchecked_Type_Conversion (Loc,
- Subtype_Mark =>
- New_Reference_To
- (Etype
- (Build_In_Place_Formal (Function_Id, BIP_Object_Access)),
- Loc),
- Expression =>
- New_Reference_To
- (Build_In_Place_Formal (Enclosing_Func, BIP_Object_Access),
- Loc));
-
- -- 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);
- Caller_Object := Empty;
-
- Establish_Transient_Scope (Object_Decl, Sec_Stack => True);
- end if;
-
- Add_Final_List_Actual_To_Build_In_Place_Call
- (Func_Call, Function_Id, Acc_Type => Empty);
-
- 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));
-
- else
- Add_Task_Actuals_To_Build_In_Place_Call
- (Func_Call, Function_Id, Make_Identifier (Loc, Name_uMaster));
- end if;
-
- Add_Access_Actual_To_Build_In_Place_Call
- (Func_Call, Function_Id, Caller_Object, Is_Access => Pass_Caller_Acc);
-
- -- Create an access type designating the function's result subtype
-
- Ref_Type :=
- Make_Defining_Identifier (Loc, New_Internal_Name ('A'));
-
- Ptr_Typ_Decl :=
- Make_Full_Type_Declaration (Loc,
- Defining_Identifier => Ref_Type,
- Type_Definition =>
- Make_Access_To_Object_Definition (Loc,
- All_Present => True,
- Subtype_Indication =>
- New_Reference_To (Result_Subt, Loc)));
-
- -- 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.
-
- if Is_Constrained (Underlying_Type (Result_Subt)) 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.
-
- Def_Id :=
- Make_Defining_Identifier (Loc,
- Chars => New_Internal_Name ('R'));
- Set_Etype (Def_Id, Ref_Type);
-
- New_Expr :=
- Make_Reference (Loc,
- Prefix => Relocate_Node (Func_Call));
-
- Insert_After_And_Analyze (Ptr_Typ_Decl,
- Make_Object_Declaration (Loc,
- Defining_Identifier => Def_Id,
- Object_Definition => New_Reference_To (Ref_Type, Loc),
- Expression => New_Expr));
-
- if Is_Constrained (Underlying_Type (Result_Subt)) then
- Set_Expression (Object_Decl, Empty);
- Set_No_Initialization (Object_Decl);
-
- -- In case of an unconstrained result subtype, rewrite the object
- -- declaration as an object renaming where the renamed object is a
- -- dereference of <function_Call>'reference:
- --
- -- Obj : Subt renames <function_call>'Ref.all;
-
- else
- Call_Deref :=
- Make_Explicit_Dereference (Loc,
- Prefix => New_Reference_To (Def_Id, Loc));
-
- Rewrite (Object_Decl,
- Make_Object_Renaming_Declaration (Loc,
- Defining_Identifier => Make_Defining_Identifier (Loc,
- New_Internal_Name ('D')),
- Access_Definition => Empty,
- Subtype_Mark => New_Occurrence_Of (Result_Subt, Loc),
- Name => Call_Deref));
-
- Set_Renamed_Object (Defining_Identifier (Object_Decl), Call_Deref);
-
- Analyze (Object_Decl);
-
- -- Replace the internal identifier of the renaming declaration's
- -- entity with identifier of the original object entity. We also have
- -- to exchange the entities containing their defining identifiers to
- -- ensure the correct replacement of the object declaration by the
- -- object renaming declaration to avoid homograph conflicts (since
- -- the object declaration's defining identifier was already entered
- -- in current scope). The Next_Entity links of the two entities also
- -- have to be swapped since the entities are part of the return
- -- scope's entity list and the list structure would otherwise be
- -- corrupted.
-
- declare
- Renaming_Def_Id : constant Entity_Id :=
- Defining_Identifier (Object_Decl);
- Next_Entity_Temp : constant Entity_Id :=
- Next_Entity (Renaming_Def_Id);
- begin
- Set_Chars (Renaming_Def_Id, Chars (Obj_Def_Id));
-
- -- Swap next entity links in preparation for exchanging entities
-
- Set_Next_Entity (Renaming_Def_Id, Next_Entity (Obj_Def_Id));
- Set_Next_Entity (Obj_Def_Id, Next_Entity_Temp);
-
- Exchange_Entities (Renaming_Def_Id, Obj_Def_Id);
- end;
- end if;
-
- -- If the object entity has a class-wide Etype, then we need to change
- -- it to the result subtype of the function call, because otherwise the
- -- object will be class-wide without an explicit initialization and
- -- won't be allocated properly by the back end. It seems unclean to make
- -- such a revision to the type at this point, and we should try to
- -- improve this treatment when build-in-place functions with class-wide
- -- results are implemented. ???
-
- if Is_Class_Wide_Type (Etype (Defining_Identifier (Object_Decl))) then
- Set_Etype (Defining_Identifier (Object_Decl), Result_Subt);
- end if;
- end Make_Build_In_Place_Call_In_Object_Declaration;
-
- --------------------------
- -- Needs_BIP_Final_List --
- --------------------------
-
- function Needs_BIP_Final_List (E : Entity_Id) return Boolean is
- pragma Assert (Is_Build_In_Place_Function (E));
- Result_Subt : constant Entity_Id := Underlying_Type (Etype (E));
-
- begin
- -- We need the BIP_Final_List if the result type needs finalization. We
- -- also need it for tagged types, even if not class-wide, because some
- -- type extension might need finalization, and all overriding functions
- -- must have the same calling conventions. However, if there is a
- -- pragma Restrictions (No_Finalization), we never need this parameter.
-
- return (Needs_Finalization (Result_Subt)
- or else Is_Tagged_Type (Underlying_Type (Result_Subt)))
- and then not Restriction_Active (No_Finalization);
- end Needs_BIP_Final_List;
-
-end Exp_Ch6;