-- --
-- B o d y --
-- --
--- Copyright (C) 1992-2004, Free Software Foundation, Inc. --
+-- Copyright (C) 1992-2009, Free Software Foundation, Inc. --
-- --
-- GNAT is free software; you can redistribute it and/or modify it under --
-- terms of the GNU General Public License as published by the Free Soft- --
--- ware Foundation; either version 2, or (at your option) any later ver- --
+-- 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 COPYING. If not, write --
--- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, --
--- MA 02111-1307, USA. --
+-- Public License distributed with GNAT; see file COPYING3. If not, go to --
+-- http://www.gnu.org/licenses for a complete copy of the license. --
-- --
-- GNAT was originally developed by the GNAT team at New York University. --
-- Extensive contributions were provided by Ada Core Technologies Inc. --
with Einfo; use Einfo;
with 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_Ch11; use Exp_Ch11;
with Exp_Dbug; use Exp_Dbug;
with Exp_Disp; use Exp_Disp;
with Exp_Dist; use Exp_Dist;
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 Hostparm; use Hostparm;
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 Rident; use Rident;
with Rtsfind; use Rtsfind;
with Sem; use Sem;
+with Sem_Aux; use Sem_Aux;
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_SCIL; use Sem_SCIL;
with Sem_Util; use Sem_Util;
with Sinfo; use Sinfo;
with Snames; use Snames;
with Stand; use Stand;
with Tbuild; use Tbuild;
-with Ttypes; use Ttypes;
with Uintp; use Uintp;
with Validsw; use Validsw;
-- 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
-- we have an infinite recursion.
procedure Expand_Actuals (N : Node_Id; Subp : Entity_Id);
- -- For each actual of an in-out parameter which is a numeric conversion
- -- of the form T(A), where A denotes a variable, we insert the declaration:
+ -- 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);
+ -- 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:
+ -- 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.
-- 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 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;
function Expand_Protected_Object_Reference
(N : Node_Id;
- Scop : Entity_Id)
- return Node_Id;
+ Scop : Entity_Id) return Node_Id;
procedure Expand_Protected_Subprogram_Call
(N : Node_Id;
-- reference to the object itself, and the call becomes a call to the
-- corresponding protected subprogram.
+ function Is_Null_Procedure (Subp : Entity_Id) return Boolean;
+ -- Predicate to recognize stubbed procedures and null procedures, which
+ -- can be inlined unconditionally in all cases.
+
+ ----------------------------------------------
+ -- 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 --
--------------------------------
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.
+ -- 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
-- 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.
+ -- 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.
+ -- 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
end if;
end Process;
- function Traverse_Body is new Traverse_Func;
+ 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.
+ -- 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;
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!)
+ -- 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;
-- 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 our current scope for analyzing the declarations and code that
+ -- we will insert for the checking.
- New_Scope (Spec);
+ 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.
+ -- 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);
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.
+ -- 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,
-- also takes care of any constraint checks required for the type
-- conversion case (on both the way in and the way out).
- procedure Add_Packed_Call_By_Copy_Code;
- -- This is used when the actual involves a reference to an element
- -- of a packed array, where we can appropriately use a simpler
- -- approach than the full call by copy code. We just copy the value
- -- in and out of an appropriate temporary.
+ 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
-- 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
---------------------------
procedure Add_Call_By_Copy_Code is
- Expr : Node_Id;
- Init : Node_Id;
- Temp : Entity_Id;
- Var : Entity_Id;
- V_Typ : Entity_Id;
- Crep : Boolean;
+ 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
- Temp := Make_Defining_Identifier (Loc, New_Internal_Name ('T'));
+ 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));
Var := Make_Var (Expression (Actual));
Crep := not Same_Representation
- (Etype (Formal), Etype (Expression (Actual)));
+ (F_Typ, Etype (Expression (Actual)));
else
V_Typ := Etype (Actual);
-- 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 (Etype (Formal))
- and then
- not Is_Constrained (Etype (Formal)))
+ 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
- (Etype (Formal), New_Occurrence_Of (Var, Loc));
+ Init := OK_Convert_To (F_Typ, New_Occurrence_Of (Var, Loc));
else
- Init := Convert_To
- (Etype (Formal), New_Occurrence_Of (Var, Loc));
+ 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;
elsif Ekind (Formal) = E_Out_Parameter
and then Nkind (Actual) = N_Type_Conversion
- and then (Is_Bit_Packed_Array (Etype (Formal))
+ 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 (Etype (Formal), New_Occurrence_Of (Var, Loc));
+ Init := OK_Convert_To (F_Typ, New_Occurrence_Of (Var, Loc));
else
- Init :=
- Convert_To (Etype (Formal), New_Occurrence_Of (Var, Loc));
+ Init := Convert_To (F_Typ, New_Occurrence_Of (Var, Loc));
end if;
elsif Ekind (Formal) = E_In_Parameter then
- Init := New_Occurrence_Of (Var, Loc);
+
+ -- 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;
N_Node :=
Make_Object_Declaration (Loc,
Defining_Identifier => Temp,
- Object_Definition =>
- New_Occurrence_Of (Etype (Formal), Loc),
- Expression => Init);
+ Object_Definition => Indic,
+ Expression => Init);
Set_Assignment_OK (N_Node);
Insert_Action (N, N_Node);
-- 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);
+ Set_Is_Known_Valid (Temp, False);
+
-- If type conversion, use reverse conversion on exit
if Nkind (Actual) = N_Type_Conversion then
Rewrite (Actual, New_Reference_To (Temp, Loc));
Analyze (Actual);
- Append_To (Post_Call,
- Make_Assignment_Statement (Loc,
- Name => New_Occurrence_Of (Var, Loc),
- Expression => Expr));
+ -- 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.
- Set_Assignment_OK (Name (Last (Post_Call)));
+ 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_Packed_Call_By_Copy_Code --
+ -- Add_Simple_Call_By_Copy_Code --
----------------------------------
- procedure Add_Packed_Call_By_Copy_Code is
+ 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
- Reset_Packed_Prefix;
+ 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
- Temp := Make_Defining_Identifier (Loc, New_Internal_Name ('T'));
+ 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 variable.
+ -- 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;
- Insert_Action (N,
+ Decl :=
Make_Object_Declaration (Loc,
Defining_Identifier => Temp,
- Object_Definition =>
- New_Occurrence_Of (Etype (Formal), Loc),
- Expression => Incod));
+ 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
Make_Assignment_Statement (Loc,
Name => Lhs,
Expression => Rhs));
+ Set_Assignment_OK (Name (Last (Post_Call)));
end if;
- end Add_Packed_Call_By_Copy_Code;
+ end Add_Simple_Call_By_Copy_Code;
---------------------------
-- Check_Fortran_Logical --
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 --
--------------
return Entity (Actual);
else
- Var := Make_Defining_Identifier (Loc, New_Internal_Name ('T'));
+ Var :=
+ Make_Defining_Identifier (Loc,
+ Chars => New_Internal_Name ('T'));
N_Node :=
Make_Object_Renaming_Declaration (Loc,
procedure Reset_Packed_Prefix is
Pfx : Node_Id := Actual;
-
begin
loop
Set_Analyzed (Pfx, False);
- exit when Nkind (Pfx) /= N_Selected_Component
- and then Nkind (Pfx) /= N_Indexed_Component;
+ 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
- Formal := First_Formal (Subp);
- Actual := First_Actual (N);
-
Post_Call := New_List;
+ Formal := First_Formal (Subp);
+ Actual := First_Actual (N);
while Present (Formal) loop
E_Formal := Etype (Formal);
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
-- [in] out parameters.
elsif Is_Ref_To_Bit_Packed_Array (Actual) then
- Add_Packed_Call_By_Copy_Code;
+ 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_Possibly_Unaligned_Slice (Actual) then
Add_Call_By_Copy_Code;
- -- Deal with access types where the actual subtpe and the
+ -- 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 and a strange assertion error in namet
- -- from gnatf in bug 1215-001 ???
+ -- conversion" errors.
elsif Is_Access_Type (E_Formal)
and then not Same_Type (E_Formal, Etype (Actual))
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.
+
+ -- Note: we use Is_Volatile here rather than Treat_As_Volatile,
+ -- because this is the enforcement of a language rule that applies
+ -- only to "real" volatile variables, not e.g. to the address
+ -- clause overlay case.
+
elsif Is_Entity_Name (Actual)
- and then Treat_As_Volatile (Entity (Actual))
+ and then Is_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)
+ and then not Is_Volatile (E_Formal)
then
Add_Call_By_Copy_Code;
and then Has_Volatile_Components (Entity (Prefix (Actual)))
then
Add_Call_By_Copy_Code;
+
+ -- Add call-by-copy code for the case of scalar out parameters
+ -- when it is not known at compile time that the subtype of the
+ -- formal is a subrange of the subtype of the actual (or vice
+ -- versa for in out parameters), in order to get range checks
+ -- on such actuals. (Maybe this case should be handled earlier
+ -- in the if statement???)
+
+ elsif Is_Scalar_Type (E_Formal)
+ and then
+ (not In_Subrange_Of (E_Formal, Etype (Actual))
+ or else
+ (Ekind (Formal) = E_In_Out_Parameter
+ and then not In_Subrange_Of (Etype (Actual), E_Formal)))
+ then
+ -- Perhaps the setting back to False should be done within
+ -- Add_Call_By_Copy_Code, since it could get set on other
+ -- cases occurring above???
+
+ if Do_Range_Check (Actual) then
+ Set_Do_Range_Check (Actual, False);
+ end if;
+
+ Add_Call_By_Copy_Code;
end if;
-- Processing for IN parameters
-- 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.
+ -- easier simply to handle all cases here.)
if Nkind (Actual) = N_Indexed_Component
and then Is_Packed (Etype (Prefix (Actual)))
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.
+ -- 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_Packed_Call_By_Copy_Code;
+ 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.
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 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 (P) = N_Triggering_Alternative
- or else Nkind (P) = N_Entry_Call_Alternative);
+ 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
end if;
end if;
- -- The call node itself is re-analyzed in Expand_Call.
+ -- The call node itself is re-analyzed in Expand_Call
end Expand_Actuals;
-- 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:
+ -- Expand_N_Procedure_Call_Statement). Processing for calls includes:
- -- Replace call to Raise_Exception by Raise_Exception always if possible
+ -- 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
procedure Expand_Call (N : Node_Id) is
Loc : constant Source_Ptr := Sloc (N);
- Remote : constant Boolean := Is_Remote_Call (N);
- Subp : Entity_Id;
- Orig_Subp : Entity_Id := Empty;
- Parent_Subp : Entity_Id;
- Parent_Formal : Entity_Id;
- Actual : Node_Id;
- Formal : Entity_Id;
- Prev : Node_Id := Empty;
- Prev_Orig : Node_Id;
- Scop : Entity_Id;
Extra_Actuals : List_Id := No_List;
- Cond : Node_Id;
+ 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.
+ -- 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.
+ -- 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. This is
- -- tested in 4723-003. 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.
+ -- 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 --
Set_First_Named_Actual (N, Actual_Expr);
if No (Prev) then
- if not Present (Parameter_Associations (N)) then
+ if No (Parameter_Associations (N)) then
Set_Parameter_Associations (N, New_List);
Append (Insert_Param, Parameter_Associations (N));
end if;
Make_Identifier (Loc, Chars (EF))));
Analyze_And_Resolve (Expr, Etype (EF));
+
+ if Nkind (N) = N_Function_Call then
+ Set_Is_Accessibility_Actual (Parent (Expr));
+ end if;
end Add_Extra_Actual;
---------------------------
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 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)))));
+ Subtype_Indication
+ (Type_Definition (Original_Node (Parent (S))));
if Nkind (Indic) = N_Subtype_Indication then
Par := Entity (Subtype_Mark (Indic));
or else not In_Open_Scopes (Scope (Par))
then
return Empty;
-
else
Gen_Par := Generic_Parent_Type (Parent (Par));
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 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);
+ Elmt := First_Elmt (Gen_Prim);
while Present (Elmt) loop
if Chars (Node (Elmt)) = Chars (S) then
declare
F1 : Entity_Id;
F2 : Entity_Id;
- begin
+ 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
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
-- Replace call to Raise_Exception by call to Raise_Exception_Always
-- if we can tell that the first parameter cannot possibly be null.
- -- This helps optimization and also generation of warnings.
+ -- 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 not Restriction_Active (No_Exception_Handlers)
- and then Is_RTE (Subp, RE_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)
+ -- 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_Entity (Name (N), Subp);
+ Set_Name (N, New_Occurrence_Of (Subp, Loc));
end if;
end;
end if;
end if;
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.
+ -- 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.
- -- We also generate any required range checks for actuals as we go
- -- through the loop, since this is a convenient place to do this.
+ 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;
- Formal := First_Formal (Subp);
- Actual := First_Actual (N);
+ 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 collecting corresponding actuals in Extra_Actuals.
+
+ -- We also generate any required range checks for actuals for in formals
+ -- as we go through the loop, since this is a convenient place to do it.
+ -- (Though it seems that this would be better done in Expand_Actuals???)
+
+ Formal := First_Formal (Subp);
+ Actual := First_Actual (N);
+ Param_Count := 1;
while Present (Formal) loop
- -- Generate range check if required (not activated yet ???)
+ -- Generate range check if required
--- if Do_Range_Check (Actual) then
--- Set_Do_Range_Check (Actual, False);
--- Generate_Range_Check
--- (Actual, Etype (Formal), CE_Range_Check_Failed);
--- end if;
+ if Do_Range_Check (Actual)
+ and then Ekind (Formal) = E_In_Parameter
+ 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);
- -- 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.
+ -- 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));
+ 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));
+ 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 := Prev;
+ Act_Prev : Node_Id;
begin
- -- Test for unchecked conversions as well, which can
- -- occur as out parameter actuals on calls to stream
- -- procedures.
+ -- Test for unchecked conversions as well, which can occur
+ -- as out parameter actuals on calls to stream procedures.
- while Nkind (Act_Prev) = N_Type_Conversion
- or else Nkind (Act_Prev) = N_Unchecked_Type_Conversion
+ Act_Prev := Prev;
+ while Nkind_In (Act_Prev, N_Type_Conversion,
+ N_Unchecked_Type_Conversion)
loop
Act_Prev := Expression (Act_Prev);
end loop;
- 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));
+ -- 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
- if Is_Entity_Name (Prev_Orig) then
- -- When passing an access parameter as the actual to another
- -- access parameter we need to pass along the actual's own
- -- associated access level parameter. This is done if we are
- -- in the scope of the formal access parameter (if this is an
- -- inlined body the extra formal is irrelevant).
+ -- 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;
- if Ekind (Entity (Prev_Orig)) in Formal_Kind
+ 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
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));
+ 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,
-- accessibility.
else
- Add_Extra_Actual (
- Make_Integer_Literal (Loc,
- Intval => Scope_Depth (Standard_Standard)),
- Extra_Accessibility (Formal));
+ 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.
+ -- 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));
+ 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,
+ Add_Extra_Actual
+ (Make_Integer_Literal (Loc,
Intval =>
- Object_Access_Level (Prefix (Prev_Orig))),
- Extra_Accessibility (Formal));
+ 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));
+ 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
end case;
- -- For allocators we pass the level of the execution of
- -- the called subprogram, which is one greater than the
- -- current scope level.
+ -- 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,
- Scope_Depth (Current_Scope) + 1),
- Extra_Accessibility (Formal));
+ 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.
+ -- 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_Orig))),
- Extra_Accessibility (Formal));
-
+ 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.
+ -- 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 Ekind (Etype (Formal)) /= E_Anonymous_Access_Type
- or else Access_Checks_Suppressed (Subp)
- then
- null;
+ if Ada_Version >= Ada_05 then
- elsif Debug_Flag_J then
- null;
+ -- Ada 2005 (AI-231): Check null-excluding access types
- elsif not Comes_From_Source (Prev) then
- null;
+ 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;
- elsif Is_Entity_Name (Prev)
- and then Ekind (Etype (Prev)) = E_Anonymous_Access_Type
- then
- null;
+ -- Ada_Version < Ada_05
- elsif Nkind (Prev) = N_Allocator
- or else Nkind (Prev) = N_Attribute_Reference
- then
- null;
+ else
+ if Ekind (Etype (Formal)) /= E_Anonymous_Access_Type
+ or else Access_Checks_Suppressed (Subp)
+ then
+ null;
- -- Suppress null checks when passing to access parameters
- -- of Java subprograms. (Should this be done for other
- -- foreign conventions as well ???)
+ elsif Debug_Flag_J then
+ null;
- elsif Convention (Subp) = Convention_Java then
- null;
+ elsif not Comes_From_Source (Prev) then
+ null;
- -- Ada 2005 (AI-231): do not force the check in case of Ada 2005
- -- unless it is a null-excluding type
+ elsif Is_Entity_Name (Prev)
+ and then Ekind (Etype (Prev)) = E_Anonymous_Access_Type
+ then
+ null;
- elsif Ada_Version < Ada_05
- or else Can_Never_Be_Null (Etype (Prev))
- then
- Cond :=
- Make_Op_Eq (Loc,
- Left_Opnd => Duplicate_Subexpr_No_Checks (Prev),
- Right_Opnd => Make_Null (Loc));
- Insert_Action (Prev,
- Make_Raise_Constraint_Error (Loc,
- Condition => Cond,
- Reason => CE_Access_Parameter_Is_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
+ 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, 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.
+ -- 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.
- if Nkind (Actual) = N_Indexed_Component then
- Set_Analyzed (Actual, False);
- end if;
+ -- What we do is just to unset analyzed bits on prefixes till
+ -- we reach something that does not have a prefix.
- Ensure_Valid (Actual);
+ 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;
- elsif Ekind (Formal) = E_In_Out_Parameter
- and then Validity_Check_In_Out_Params
- then
Ensure_Valid (Actual);
end if;
end if;
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 return from the procedure.
+ -- 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)
Set_Is_Known_Valid (Entity (Actual), False);
end if;
- -- For an OUT or IN OUT parameter of an access type, if the
- -- actual is an entity, then it is no longer known to be non-null.
+ -- 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 Is_Access_Type (Etype (Actual))
+ and then Present (Entity (Actual))
then
- Set_Is_Known_Non_Null (Entity (Actual), False);
+ 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! We do reset the Is_Known_Valid flag
+ -- since the subprogram could have returned in invalid value.
+
+ if (Ekind (Formal) = E_Out_Parameter
+ or else
+ Ekind (Formal) = E_In_Out_Parameter)
+ and then Is_Assignable (Ent)
+ then
+ Sav := Last_Assignment (Ent);
+ Kill_Current_Values (Ent);
+ Set_Last_Assignment (Ent, Sav);
+ Set_Is_Known_Valid (Ent, False);
+
+ -- 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
-- 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
+ if Remote and then Is_Class_Wide_Type (Etype (Formal)) then
Insert_Action (Actual,
- Make_Implicit_If_Statement (N,
- Condition =>
- Make_Op_Not (Loc,
- Get_Remotely_Callable
- (Duplicate_Subexpr_Move_Checks (Actual))),
- Then_Statements => New_List (
- Make_Raise_Program_Error (Loc,
- Reason => PE_Illegal_RACW_E_4_18))));
+ 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 assignement we need to check if
- -- tag propagation is needed. This code belongs theorically in Analyze
- -- Assignment but has to be done earlier (bottom-up) because the
- -- assignment might be transformed into a declaration for an uncons-
- -- trained value, if the expression is classwide.
+ -- 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 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 Etype (N) /= Root_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&"
- & "('R'M 5.2 (6))", N, Root_Type (Etype (Name (Ass))));
+ & "(RM 5.2 (6))", N, Root_Type (Etype (Name (Ass))));
+
else
Propagate_Tag (Name (Ass), N);
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 Java_VM, because
- -- the JVM back end directly handles the generation of dispatching
+ -- 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 (N) = N_Function_Call
- or else Nkind (N) = N_Procedure_Call_Statement)
+ if Nkind_In (N, N_Function_Call, N_Procedure_Call_Statement)
and then Present (Controlling_Argument (N))
- and then not Java_VM
then
- Expand_Dispatch_Call (N);
+ if Tagged_Type_Expansion then
+ Expand_Dispatching_Call (N);
- -- The following return is worrisome. Is it really OK to
- -- skip all remaining processing in this procedure ???
+ -- The following return is worrisome. Is it really OK to
+ -- skip all remaining processing in this procedure ???
- return;
+ return;
+
+ else
+ Apply_Tag_Checks (N);
+
+ -- 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.
+
+ 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 rewritting to occur in expanded code.
+ -- not want such a rewriting to occur in expanded code.
- elsif Is_All_Remote_Call (N) then
+ 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
end loop;
end if;
- if Ekind (Subp) = E_Procedure
- or else (Ekind (Subp) = E_Subprogram_Type
- and then Etype (Subp) = Standard_Void_Type)
- or else Is_Entry (Subp)
- then
- Expand_Actuals (N, Subp);
- 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.
end loop;
end if;
+ -- The below setting of Entity is suspect, see F109-018 discussion???
+
Set_Entity (Name (N), Parent_Subp);
- if Is_Abstract (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;
- -- Add an explicit conversion for parameter of the derived type.
- -- This is only done for scalar and access in-parameters. Others
- -- have been expanded in expand_actuals.
+ -- 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.
- Formal := First_Formal (Subp);
- Parent_Formal := First_Formal (Parent_Subp);
- Actual := First_Actual (N);
-
- -- It is not clear that conversion is needed for intrinsic
- -- subprograms, but it certainly is for those that are user-
- -- defined, and that can be inherited on derivation, namely
- -- unchecked conversion and deallocation.
- -- General case needs study ???
+ -- Not clear whether intrinsic subprograms need such conversions. ???
if not Is_Intrinsic_Subprogram (Parent_Subp)
or else Is_Generic_Instance (Parent_Subp)
then
- while Present (Formal) loop
+ 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.
- if Etype (Formal) /= Etype (Parent_Formal)
- and then Is_Scalar_Type (Etype (Formal))
- and then Ekind (Formal) = E_In_Parameter
- and then not Raises_Constraint_Error (Actual)
- then
- Rewrite (Actual,
- OK_Convert_To (Etype (Parent_Formal),
- Relocate_Node (Actual)));
+ -------------
+ -- Convert --
+ -------------
- Analyze (Actual);
- Resolve (Actual, Etype (Parent_Formal));
- Enable_Range_Check (Actual);
+ 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;
- elsif Is_Access_Type (Etype (Formal))
- and then Base_Type (Etype (Parent_Formal))
- /= Base_Type (Etype (Actual))
- then
- if Ekind (Formal) /= E_In_Parameter then
- Rewrite (Actual,
- Convert_To (Etype (Parent_Formal),
- Relocate_Node (Actual)));
-
- Analyze (Actual);
- Resolve (Actual, Etype (Parent_Formal));
-
- elsif
- Ekind (Etype (Parent_Formal)) = E_Anonymous_Access_Type
- and then Designated_Type (Etype (Parent_Formal))
- /=
- Designated_Type (Etype (Actual))
- and then not Is_Controlling_Formal (Formal)
+ -- 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);
+
+ -- If the actual has been marked as requiring a range
+ -- check, then generate it here.
+
+ if Do_Range_Check (Actual) then
+ Set_Do_Range_Check (Actual, False);
+ Generate_Range_Check
+ (Actual, Etype (Formal), CE_Range_Check_Failed);
+ end if;
+
+ -- 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
- -- 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.
+ 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)));
+
+ -- If the relocated node is a function call then it
+ -- can be part of the expansion of the predefined
+ -- equality operator of a tagged type and we may
+ -- need to adjust its SCIL dispatching node.
+
+ if Generate_SCIL
+ and then Nkind (Actual) /= N_Null
+ and then Nkind (Expression (Actual))
+ = N_Function_Call
+ then
+ Adjust_SCIL_Node (Actual, Expression (Actual));
+ end if;
+
+ Analyze (Actual);
+ Resolve (Actual, Parent_Typ);
+ end if;
- Rewrite (Actual,
- Unchecked_Convert_To (Etype (Parent_Formal),
- Relocate_Node (Actual)));
+ -- For array and record types, the parent formal type and
+ -- derived formal type have different sizes or pragma Pack
+ -- status.
- Analyze (Actual);
- Resolve (Actual, Etype (Parent_Formal));
+ 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;
- end if;
- Next_Formal (Formal);
- Next_Formal (Parent_Formal);
- Next_Actual (Actual);
- end loop;
+ Next_Actual (Actual);
+ Next_Formal (Formal);
+ Next_Formal (Parent_Formal);
+ end loop;
+ end;
end if;
Orig_Subp := Subp;
-- Handle case of access to protected subprogram type
- if Ekind (Base_Type (Etype (Prefix (Name (N))))) =
- E_Access_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).
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, Nam);
+ 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);
Prepend (Obj, Parm);
if Etype (D_T) = Standard_Void_Type then
- Call := Make_Procedure_Call_Statement (Loc,
- Name => Nam,
- Parameter_Associations => Parm);
+ Call :=
+ Make_Procedure_Call_Statement (Loc,
+ Name => Nam,
+ Parameter_Associations => Parm);
else
- Call := Make_Function_Call (Loc,
- Name => Nam,
- Parameter_Associations => Parm);
+ Call :=
+ Make_Function_Call (Loc,
+ Name => Nam,
+ Parameter_Associations => Parm);
end if;
Set_First_Named_Actual (Call, First_Named_Actual (N));
-- 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
+ -- We perform two simple optimization on calls:
+
+ -- a) replace calls to null procedures unconditionally;
+
+ -- b) for To_Address, just do an unchecked conversion. Not only is
+ -- this efficient, but it also avoids order of elaboration problems
+ -- when address clauses are inlined (address expression elaborated
+ -- at the wrong point).
+
+ -- We perform these optimization regardless of whether we are in the
+ -- main unit or in a unit in the context of the main unit, to ensure
+ -- that tree generated is the same in both cases, for Inspector use.
+
+ if Is_RTE (Subp, RE_To_Address) then
+ Rewrite (N,
+ Unchecked_Convert_To
+ (RTE (RE_Address), Relocate_Node (First_Actual (N))));
+ return;
+
+ elsif Is_Null_Procedure (Subp) then
+ Rewrite (N, Make_Null_Statement (Loc));
+ return;
+ end if;
+
if Is_Inlined (Subp) then
Inlined_Subprogram : declare
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.
+ -- 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 := Scop;
+ S : Entity_Id;
begin
+ S := Scop;
while Present (S)
and then S /= Standard_Standard
loop
-- 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 gigi.
+ -- 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
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.
+ -- 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))
if (In_Extended_Main_Code_Unit (N)
or else In_Extended_Main_Code_Unit (Parent (N))
- or else Is_Always_Inlined (Subp))
+ 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))
and then In_Same_Extended_Unit (Sloc (Spec), Loc)
then
Cannot_Inline
- ("cannot inline& (body not seen yet)?",
- N, Subp);
+ ("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.
+ -- Check for 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.
+ -- If the call is an internal one, it is rewritten as a call to the
+ -- corresponding unprotected subprogram.
Expand_Protected_Subprogram_Call (N, Subp, Scop);
end if;
- -- Functions returning controlled objects need special attention
+ -- Functions returning controlled objects need special attention:
+ -- if the return type is limited, the context is an initialization
+ -- and different processing applies. If the call is to a protected
+ -- function, the expansion above will call Expand_Call recusively.
+ -- To prevent a double attachment, check that the current call is
+ -- not a rewriting of a protected function call.
- if Controlled_Type (Etype (Subp))
- and then not Is_Return_By_Reference_Type (Etype (Subp))
+ if Needs_Finalization (Etype (Subp))
+ and then not Is_Inherently_Limited_Type (Etype (Subp))
+ and then
+ (No (First_Formal (Subp))
+ or else
+ not Is_Concurrent_Record_Type (Etype (First_Formal (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.
+ -- 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))
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 will hold the last actual that should be kept.
+ -- 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.
+ -- 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);
-- If no arguments, delete entire list, this is the easy case
if No (Last_Keep_Arg) then
- while Is_Non_Empty_List (Parameter_Associations (N)) loop
- Delete_Tree (Remove_Head (Parameter_Associations (N)));
- end loop;
-
Set_Parameter_Associations (N, No_List);
Set_First_Named_Actual (N, Empty);
elsif Is_List_Member (Last_Keep_Arg) then
while Present (Next (Last_Keep_Arg)) loop
- Delete_Tree (Remove_Next (Last_Keep_Arg));
+ Discard_Node (Remove_Next (Last_Keep_Arg));
end loop;
Set_First_Named_Actual (N, Empty);
Temp : Node_Id;
Passoc : Node_Id;
- Discard : Node_Id;
- pragma Warnings (Off, Discard);
-
begin
-- First step, remove all the named parameters from the
-- list (they are still chained using First_Named_Actual
end loop;
while Present (Next (Temp)) loop
- Discard := Remove_Next (Temp);
+ Remove (Next (Temp));
end loop;
end if;
exit when No (Temp);
Set_Next_Named_Actual
(Passoc, Next_Named_Actual (Parent (Temp)));
- Delete_Tree (Temp);
end loop;
end;
+
end if;
end;
end if;
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;
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.
+
procedure Make_Exit_Label;
- -- Build declaration for exit label to be used in Return statements.
+ -- Build declaration for exit label to be used in Return statements,
+ -- sets Exit_Lab (the label node) and Lab_Decl (corresponding implcit
+ -- declaration).
function Process_Formals (N : Node_Id) return Traverse_Result;
- -- Replace occurrence of a formal with the corresponding actual, or
- -- the thunk generated for it.
+ -- 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.
+ -- 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.
+ -- 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
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.
+ -- 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
---------------------
-- Make_Exit_Label --
procedure Make_Exit_Label is
begin
- -- Create exit label for subprogram, if one doesn't exist yet.
+ -- Create exit label for subprogram if one does not exist yet
if No (Exit_Lab) then
- Lab_Id := Make_Identifier (Loc, New_Internal_Name ('L'));
+ 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);
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 -- numeric literal
+ else
Rewrite (N, New_Copy (A));
end if;
end if;
return Skip;
- elsif Nkind (N) = N_Return_Statement then
-
+ 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)));
+ Rewrite (N,
+ Make_Goto_Statement (Loc,
+ Name => New_Copy (Lab_Id)));
else
if Nkind (Parent (N)) = N_Handled_Sequence_Of_Statements
-- 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, eg. when the expression is a numeric literal and
+ -- 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 (Expression (N)) = N_Aggregate
- or else Nkind (Expression (N)) = N_Null
- then
+ 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)),
-- not be posting warnings on the inlined body so it is unneeded.
elsif Nkind (N) = N_Pragma
- and then Chars (N) = Name_Unreferenced
+ and then Pragma_Name (N) = Name_Unreferenced
then
Rewrite (N, Make_Null_Statement (Sloc (N)));
return OK;
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.
+ -- 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)))
+ 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).
+ -- 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.
+ -- 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);
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;
procedure Rewrite_Procedure_Call (N : Node_Id; Blk : Node_Id) is
HSS : constant Node_Id := Handled_Statement_Sequence (Blk);
begin
- if Is_Empty_List (Declarations (Blk)) then
+ -- 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
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 a
- -- problem with order of elaboration when address clauses
- -- are inlined (address expr elaborated at wrong point).
-
- if Subp = RTE (RE_To_Address) then
- Rewrite (N,
- Unchecked_Convert_To
- (RTE (RE_Address),
- Relocate_Node (First_Actual (N))));
+
+ -- 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 then
-
+ 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.
+ -- 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;
Set_Declarations (Blk, New_List);
end if;
- -- If this is a derived function, establish the proper return type.
+ -- 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
Ret_Type := Etype (Subp);
end if;
- F := First_Formal (Subp);
- A := First_Actual (N);
-
-- 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);
+ 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.
+ -- 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))
-- 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))
- or else Nkind (A) = N_Real_Literal
- or else Nkind (A) = N_Integer_Literal
- or else Nkind (A) = N_Character_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
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)));
+ 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));
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.
+
+ -- We also use a renaming declaration for expressions of an array
+ -- type that is not bit-packed, both for efficiency reasons and to
+ -- respect the semantics of the call: in most cases the original
+ -- call will pass the parameter by reference, and thus the inlined
+ -- code will have the same semantics.
+
if Ekind (F) = E_In_Parameter
and then not Is_Limited_Type (Etype (A))
+ and then not Is_Tagged_Type (Etype (A))
+ and then
+ (not Is_Array_Type (Etype (A))
+ or else not Is_Object_Reference (A)
+ or else Is_Bit_Packed_Array (Etype (A)))
then
Decl :=
Make_Object_Declaration (Loc,
Name => New_A);
end if;
- Prepend (Decl, Declarations (Blk));
+ Append (Decl, Decls);
Set_Renamed_Object (F, Temp);
end if;
-- 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.
+ -- simple enough, i.e. an entity or an explicit dereference of one.
if Ekind (Subp) = E_Function then
if Nkind (Parent (N)) = N_Assignment_Statement
then
Targ := Name (Parent (N));
+ elsif Nkind (Parent (N)) = N_Assignment_Statement
+ and then Nkind (Name (Parent (N))) = N_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.
+ -- Replace call with temporary and create its declaration
Temp :=
Make_Defining_Identifier (Loc, New_Internal_Name ('C'));
+ Set_Is_Internal (Temp);
- Decl :=
- Make_Object_Declaration (Loc,
- Defining_Identifier => Temp,
- Object_Definition =>
- New_Occurrence_Of (Ret_Type, Loc));
+ -- 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.
- Set_No_Initialization (Decl);
- Insert_Action (N, Decl);
- Rewrite (N, New_Occurrence_Of (Temp, Loc));
- Targ := Temp;
- end if;
- end if;
+ if Is_Unc then
+ Decl :=
+ Make_Object_Declaration (Loc,
+ Defining_Identifier => Temp,
+ Object_Definition =>
+ New_Copy_Tree (Object_Definition (Parent (Targ1))));
- -- Traverse the tree and replace formals with actuals or their thunks.
- -- Attach block to tree before analysis and rewriting.
+ Replace_Formals (Decl);
- Replace_Formals (Blk);
+ 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)
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.
+ -- 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);
----------------------------
procedure Expand_N_Function_Call (N : Node_Id) is
- Typ : constant Entity_Id := Etype (N);
-
- function Returned_By_Reference return Boolean;
- -- If the return type is returned through the secondary stack. that is
- -- by reference, we don't want to create a temp to force stack checking.
- -- Shouldn't this function be moved to exp_util???
-
- ---------------------------
- -- Returned_By_Reference --
- ---------------------------
-
- function Returned_By_Reference return Boolean is
- S : Entity_Id := Current_Scope;
-
- begin
- if Is_Return_By_Reference_Type (Typ) then
- return True;
-
- elsif Nkind (Parent (N)) /= N_Return_Statement then
- return False;
-
- elsif Requires_Transient_Scope (Typ) then
-
- -- Verify that the return type of the enclosing function has
- -- the same constrained status as that of the expression.
-
- while Ekind (S) /= E_Function loop
- S := Scope (S);
- end loop;
-
- return Is_Constrained (Typ) = Is_Constrained (Etype (S));
- else
- return False;
- end if;
- end Returned_By_Reference;
-
- -- Start of processing for Expand_N_Function_Call
-
begin
- -- A special check. If stack checking is enabled, and the return type
- -- might generate a large temporary, and the call is not the right
- -- side of an assignment, then generate an explicit temporary. We do
- -- this because otherwise gigi may generate a large temporary on the
- -- fly and this can cause trouble with stack checking.
-
- if May_Generate_Large_Temp (Typ)
- and then Nkind (Parent (N)) /= N_Assignment_Statement
- and then
- (Nkind (Parent (N)) /= N_Qualified_Expression
- or else Nkind (Parent (Parent (N))) /= N_Assignment_Statement)
- and then
- (Nkind (Parent (N)) /= N_Object_Declaration
- or else Expression (Parent (N)) /= N)
- and then not Returned_By_Reference
- then
- if Stack_Checking_Enabled then
-
- -- Note: it might be thought that it would be OK to use a call
- -- to Force_Evaluation here, but that's not good enough, because
- -- that can results in a 'Reference construct that may still
- -- need a temporary.
-
- declare
- Loc : constant Source_Ptr := Sloc (N);
- Temp_Obj : constant Entity_Id :=
- Make_Defining_Identifier (Loc,
- Chars => New_Internal_Name ('F'));
- Temp_Typ : Entity_Id := Typ;
- Decl : Node_Id;
- A : Node_Id;
- F : Entity_Id;
- Proc : Entity_Id;
-
- begin
- if Is_Tagged_Type (Typ)
- and then Present (Controlling_Argument (N))
- then
- if Nkind (Parent (N)) /= N_Procedure_Call_Statement
- and then Nkind (Parent (N)) /= N_Function_Call
- then
- -- If this is a tag-indeterminate call, the object must
- -- be classwide.
-
- if Is_Tag_Indeterminate (N) then
- Temp_Typ := Class_Wide_Type (Typ);
- end if;
-
- else
- -- If this is a dispatching call that is itself the
- -- controlling argument of an enclosing call, the
- -- nominal subtype of the object that replaces it must
- -- be classwide, so that dispatching will take place
- -- properly. If it is not a controlling argument, the
- -- object is not classwide.
-
- Proc := Entity (Name (Parent (N)));
- F := First_Formal (Proc);
- A := First_Actual (Parent (N));
-
- while A /= N loop
- Next_Formal (F);
- Next_Actual (A);
- end loop;
-
- if Is_Controlling_Formal (F) then
- Temp_Typ := Class_Wide_Type (Typ);
- end if;
- end if;
- end if;
-
- Decl :=
- Make_Object_Declaration (Loc,
- Defining_Identifier => Temp_Obj,
- Object_Definition => New_Occurrence_Of (Temp_Typ, Loc),
- Constant_Present => True,
- Expression => Relocate_Node (N));
- Set_Assignment_OK (Decl);
-
- Insert_Actions (N, New_List (Decl));
- Rewrite (N, New_Occurrence_Of (Temp_Obj, Loc));
- end;
-
- else
- -- If stack-checking is not enabled, increment serial number
- -- for internal names, so that subsequent symbols are consistent
- -- with and without stack-checking.
-
- Synchronize_Serial_Number;
-
- -- Now we can expand the call with consistent symbol names
-
- Expand_Call (N);
- end if;
-
- -- Normal case, expand the call
+ Expand_Call (N);
- else
- 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, no-op 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_Subprogram_Body --
------------------------------
- -- Add poll call if ATC polling is enabled
+ -- 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 is 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 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
Loc : constant Source_Ptr := Sloc (N);
H : constant Node_Id := Handled_Statement_Sequence (N);
Body_Id : Entity_Id;
- Spec_Id : Entity_Id;
Except_H : Node_Id;
- Scop : Entity_Id;
- Dec : Node_Id;
- Next_Op : 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.
-
- procedure Expand_Thread_Body;
- -- Perform required expansion of a thread body
+ -- 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
- begin
- if not Is_Transfer (Last (S)) then
-
- -- The source location for the return is the end label
- -- of the procedure in all cases. This is a bit odd when
- -- there are exception handlers, but not much else we can do.
-
- Append_To (S, Make_Return_Statement (Sloc (End_Label (H))));
- end if;
- end Add_Return;
-
- ------------------------
- -- Expand_Thread_Body --
- ------------------------
-
- -- The required expansion of a thread body is as follows
-
- -- procedure <thread body procedure name> is
-
- -- _Secondary_Stack : aliased
- -- Storage_Elements.Storage_Array
- -- (1 .. Storage_Offset (Sec_Stack_Size));
- -- for _Secondary_Stack'Alignment use Standard'Maximum_Alignment;
-
- -- _Process_ATSD : aliased System.Threads.ATSD;
-
- -- begin
- -- System.Threads.Thread_Body_Enter;
- -- (_Secondary_Stack'Address,
- -- _Secondary_Stack'Length,
- -- _Process_ATSD'Address);
-
- -- declare
- -- <user declarations>
- -- begin
- -- <user statements>
- -- <user exception handlers>
- -- end;
-
- -- System.Threads.Thread_Body_Leave;
-
- -- exception
- -- when E : others =>
- -- System.Threads.Thread_Body_Exceptional_Exit (E);
- -- end;
-
- -- Note the exception handler is omitted if pragma Restriction
- -- No_Exception_Handlers is currently active.
-
- procedure Expand_Thread_Body is
- User_Decls : constant List_Id := Declarations (N);
- Sec_Stack_Len : Node_Id;
-
- TB_Pragma : constant Node_Id :=
- Get_Rep_Pragma (Spec_Id, Name_Thread_Body);
-
- Ent_SS : Entity_Id;
- Ent_ATSD : Entity_Id;
- Ent_EO : Entity_Id;
-
- Decl_SS : Node_Id;
- Decl_ATSD : Node_Id;
-
- Excep_Handlers : List_Id;
+ Last_Stm : Node_Id;
+ Loc : Source_Ptr;
begin
- New_Scope (Spec_Id);
-
- -- Get proper setting for secondary stack size
-
- if List_Length (Pragma_Argument_Associations (TB_Pragma)) = 2 then
- Sec_Stack_Len :=
- Expression (Last (Pragma_Argument_Associations (TB_Pragma)));
- else
- Sec_Stack_Len :=
- New_Occurrence_Of (RTE (RE_Default_Secondary_Stack_Size), Loc);
- end if;
-
- Sec_Stack_Len := Convert_To (RTE (RE_Storage_Offset), Sec_Stack_Len);
-
- -- Build and set declarations for the wrapped thread body
-
- Ent_SS := Make_Defining_Identifier (Loc, Name_uSecondary_Stack);
- Ent_ATSD := Make_Defining_Identifier (Loc, Name_uProcess_ATSD);
-
- Decl_SS :=
- Make_Object_Declaration (Loc,
- Defining_Identifier => Ent_SS,
- Aliased_Present => True,
- Object_Definition =>
- Make_Subtype_Indication (Loc,
- Subtype_Mark =>
- New_Occurrence_Of (RTE (RE_Storage_Array), Loc),
- Constraint =>
- Make_Index_Or_Discriminant_Constraint (Loc,
- Constraints => New_List (
- Make_Range (Loc,
- Low_Bound => Make_Integer_Literal (Loc, 1),
- High_Bound => Sec_Stack_Len)))));
-
- Decl_ATSD :=
- Make_Object_Declaration (Loc,
- Defining_Identifier => Ent_ATSD,
- Aliased_Present => True,
- Object_Definition => New_Occurrence_Of (RTE (RE_ATSD), Loc));
-
- Set_Declarations (N, New_List (Decl_SS, Decl_ATSD));
- Analyze (Decl_SS);
- Analyze (Decl_ATSD);
- Set_Alignment (Ent_SS, UI_From_Int (Maximum_Alignment));
-
- -- Create new exception handler
-
- if Restriction_Active (No_Exception_Handlers) then
- Excep_Handlers := No_List;
+ -- Get last statement, ignoring any Pop_xxx_Label nodes, which are
+ -- not relevant in this context since they are not executable.
- else
- Check_Restriction (No_Exception_Handlers, N);
+ Last_Stm := Last (S);
+ while Nkind (Last_Stm) in N_Pop_xxx_Label loop
+ Prev (Last_Stm);
+ end loop;
- Ent_EO := Make_Defining_Identifier (Loc, Name_uE);
+ -- Now insert return unless last statement is a transfer
- Excep_Handlers := New_List (
- Make_Exception_Handler (Loc,
- Choice_Parameter => Ent_EO,
- Exception_Choices => New_List (
- Make_Others_Choice (Loc)),
- Statements => New_List (
- Make_Procedure_Call_Statement (Loc,
- Name =>
- New_Occurrence_Of
- (RTE (RE_Thread_Body_Exceptional_Exit), Loc),
- Parameter_Associations => New_List (
- New_Occurrence_Of (Ent_EO, Loc))))));
- end if;
+ if not Is_Transfer (Last_Stm) then
- -- Now build new handled statement sequence and analyze it
+ -- 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.
- Set_Handled_Statement_Sequence (N,
- Make_Handled_Sequence_Of_Statements (Loc,
- Statements => New_List (
+ if Nkind (Parent (S)) = N_Exception_Handler
+ and then not Comes_From_Source (Parent (S))
+ then
+ Loc := Sloc (Last_Stm);
- Make_Procedure_Call_Statement (Loc,
- Name => New_Occurrence_Of (RTE (RE_Thread_Body_Enter), Loc),
- Parameter_Associations => New_List (
+ elsif Present (End_Label (H)) then
+ Loc := Sloc (End_Label (H));
- Make_Attribute_Reference (Loc,
- Prefix => New_Occurrence_Of (Ent_SS, Loc),
- Attribute_Name => Name_Address),
+ else
+ Loc := Sloc (Last_Stm);
+ end if;
- Make_Attribute_Reference (Loc,
- Prefix => New_Occurrence_Of (Ent_SS, Loc),
- Attribute_Name => Name_Length),
+ declare
+ Rtn : constant Node_Id := Make_Simple_Return_Statement (Loc);
- Make_Attribute_Reference (Loc,
- Prefix => New_Occurrence_Of (Ent_ATSD, Loc),
- Attribute_Name => Name_Address))),
+ begin
+ -- Append return statement, and set analyzed manually. We can't
+ -- call Analyze on this return since the scope is wrong.
- Make_Block_Statement (Loc,
- Declarations => User_Decls,
- Handled_Statement_Sequence => H),
+ -- Note: it almost works to push the scope and then do the
+ -- Analyze call, but something goes wrong in some weird cases
+ -- and it is not worth worrying about ???
- Make_Procedure_Call_Statement (Loc,
- Name => New_Occurrence_Of (RTE (RE_Thread_Body_Leave), Loc))),
+ Append_To (S, Rtn);
+ Set_Analyzed (Rtn);
- Exception_Handlers => Excep_Handlers));
+ -- Call _Postconditions procedure if appropriate. We need to
+ -- do this explicitly because we did not analyze the generated
+ -- return statement above, so the call did not get inserted.
- Analyze (Handled_Statement_Sequence (N));
- End_Scope;
- end Expand_Thread_Body;
+ if Ekind (Spec_Id) = E_Procedure
+ and then Has_Postconditions (Spec_Id)
+ then
+ pragma Assert (Present (Postcondition_Proc (Spec_Id)));
+ Insert_Action (Rtn,
+ Make_Procedure_Call_Statement (Loc,
+ Name =>
+ New_Reference_To (Postcondition_Proc (Spec_Id), Loc)));
+ end if;
+ end;
+ 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.
+ -- 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 (Handled_Statement_Sequence (N));
+ L := Statements (H);
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.
+ -- If local-exception-to-goto optimization active, insert dummy push
+ -- statements at start, and dummy pop statements at end.
- if Is_Non_Empty_List (L) then
- Generate_Poll_Call (First (L));
+ 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
Spec_Id := Body_Id;
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.
+ -- 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.
+
+ if Is_Non_Empty_List (L) then
+
+ -- Do not add a polling call if the subprogram is to be inlined by
+ -- the back-end, to avoid repeated calls with multiple inlinings.
+
+ 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 ???
+ -- 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 := First_Formal (Spec_Id);
+ 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 Init_Or_Norm_Scalars and then Is_Subprogram (Spec_Id) then
declare
- F : Entity_Id := First_Formal (Spec_Id);
- V : constant Boolean := Validity_Checks_On;
+ F : Entity_Id;
begin
- -- We turn off validity checking, since we do not want any
- -- check on the initializing value itself (which we know
- -- may well be invalid!)
-
- Validity_Checks_On := False;
-
-- 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), 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;
-
- Validity_Checks_On := V;
end;
end if;
- Scop := Scope (Spec_Id);
-
- -- Add discriminal renamings to protected subprograms.
- -- Install new discriminals for expansion of the next
- -- subprogram of this protected type, if any.
-
- if Is_List_Member (N)
- and then Present (Parent (List_Containing (N)))
- and then Nkind (Parent (List_Containing (N))) = N_Protected_Body
- then
- Add_Discriminal_Declarations
- (Declarations (N), Scop, Name_uObject, Loc);
- Add_Private_Declarations (Declarations (N), Scop, Name_uObject, Loc);
-
- -- Associate privals and discriminals with the next protected
- -- operation body to be expanded. These are used to expand
- -- references to private data objects and discriminants,
- -- respectively.
-
- Next_Op := Next_Protected_Operation (N);
-
- if Present (Next_Op) then
- Dec := Parent (Base_Type (Scop));
- Set_Privals (Dec, Next_Op, Loc);
- Set_Discriminals (Dec);
- end if;
- end if;
-
-- Clear out statement list for stubbed procedure
if Present (Corresponding_Spec (N)) then
end if;
end if;
- -- Returns_By_Ref flag is normally set when the subprogram is frozen
- -- but subprograms with no specs are not frozen
+ -- 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);
then
null;
- elsif Is_Return_By_Reference_Type (Typ) then
+ elsif Is_Inherently_Limited_Type (Typ) then
Set_Returns_By_Ref (Spec_Id);
- elsif Present (Utyp) and then Controlled_Type (Utyp) then
+ 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.
+ -- For a procedure, we add a return for all possible syntactic ends of
+ -- the subprogram.
if Ekind (Spec_Id) = E_Procedure
or else Ekind (Spec_Id) = E_Generic_Procedure
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:
+ -- 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
-- ...
-- 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)).
+ -- 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).
+ -- 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
Make_Handled_Sequence_Of_Statements (Hloc,
Statements => New_List (Blok, Rais)));
- New_Scope (Spec_Id);
+ Push_Scope (Spec_Id);
Analyze (Blok);
Analyze (Rais);
Pop_Scope;
Detect_Infinite_Recursion (N, Spec_Id);
end if;
- -- Finally, if we are in Normalize_Scalars mode, then any scalar out
- -- parameters must be initialized to the appropriate default value.
-
- if Ekind (Spec_Id) = E_Procedure and then Normalize_Scalars then
- declare
- Floc : Source_Ptr;
- Formal : Entity_Id;
- Stm : Node_Id;
-
- begin
- Formal := First_Formal (Spec_Id);
-
- while Present (Formal) loop
- Floc := Sloc (Formal);
-
- if Ekind (Formal) = E_Out_Parameter
- and then Is_Scalar_Type (Etype (Formal))
- then
- Stm :=
- Make_Assignment_Statement (Floc,
- Name => New_Occurrence_Of (Formal, Floc),
- Expression =>
- Get_Simple_Init_Val (Etype (Formal), Floc));
- Prepend (Stm, Declarations (N));
- Analyze (Stm);
- end if;
-
- Next_Formal (Formal);
- end loop;
- end;
- end if;
-
- -- Deal with thread body
-
- if Is_Thread_Body (Spec_Id) then
- Expand_Thread_Body;
- end if;
-
- -- If the subprogram does not have pending instantiations, then we
- -- must generate the subprogram descriptor now, since the code for
- -- the subprogram is complete, and this is our last chance. However
- -- if there are pending instantiations, then the code is not
- -- complete, and we will delay the generation.
-
- if Is_Subprogram (Spec_Id)
- and then not Delay_Subprogram_Descriptors (Spec_Id)
- then
- Generate_Subprogram_Descriptor_For_Subprogram (N, Spec_Id);
- end if;
-
-- Set to encode entity names in package body before gigi is called
Qualify_Entity_Names (N);
-- 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);
Prot_Id : Entity_Id;
begin
- -- Deal with case of protected subprogram. Do not generate
- -- protected operation if operation is flagged as eliminated.
+ -- 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)))
Make_Subprogram_Declaration (Loc,
Specification =>
Build_Protected_Sub_Specification
- (N, Scop, Unprotected => True));
+ (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.
Insert_Before (Prot_Bod, Prot_Decl);
Prot_Id := Defining_Unit_Name (Specification (Prot_Decl));
+ Set_Has_Delayed_Freeze (Prot_Id);
- New_Scope (Scope (Scop));
+ Push_Scope (Scope (Scop));
Analyze (Prot_Decl);
- Create_Extra_Formals (Prot_Id);
+ Insert_Actions (N, Freeze_Entity (Prot_Id, Loc));
Set_Protected_Body_Subprogram (Subp, Prot_Id);
+
+ -- Create protected operation as well. Even though the operation
+ -- is only accessible within the body, it is possible to make it
+ -- available outside of the protected object by using 'Access to
+ -- provide a callback, so build protected version in all cases.
+
+ Prot_Decl :=
+ Make_Subprogram_Declaration (Loc,
+ Specification =>
+ Build_Protected_Sub_Specification (N, Scop, Protected_Mode));
+ Insert_Before (Prot_Bod, Prot_Decl);
+ Analyze (Prot_Decl);
+
Pop_Scope;
end if;
+
+ -- Ada 2005 (AI-348): Generate body for a null procedure.
+ -- In most cases this is superfluous because calls to it
+ -- will be automatically inlined, but we definitely need
+ -- the body if preconditions for the procedure are present.
+
+ elsif Nkind (Specification (N)) = N_Procedure_Specification
+ and then Null_Present (Specification (N))
+ then
+ declare
+ Bod : constant Node_Id := Body_To_Inline (N);
+
+ begin
+ Set_Has_Completion (Subp, False);
+ Append_Freeze_Action (Subp, Bod);
+
+ -- The body now contains raise statements, so calls to it will
+ -- not be inlined.
+
+ Set_Is_Inlined (Subp, False);
+ end;
end if;
end Expand_N_Subprogram_Declaration;
function Expand_Protected_Object_Reference
(N : Node_Id;
- Scop : Entity_Id)
- return Node_Id
+ Scop : Entity_Id) return Node_Id
is
Loc : constant Source_Ptr := Sloc (N);
Corr : Entity_Id;
Proc : Entity_Id;
begin
- Rec := Make_Identifier (Loc, Name_uObject);
+ 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
- -- 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.
+ -- 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
if Is_Subprogram (Proc)
and then Proc /= Corr
then
- -- Protected function or procedure.
+ -- 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.
+ -- 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 a
- -- pointer to the object. We create a local variable
- -- of the proper type, duplicating what is done to define
- -- _object later on.
+ -- 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;
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 renalyzed after
- -- rewriting.
+ -- 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 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;
- -----------------------
- -- Freeze_Subprogram --
- -----------------------
+ -- Analyze and resolve the new call. The actuals have already been
+ -- resolved, but expansion of a function call will add extra actuals
+ -- if needed. Analysis of a procedure call already includes resolution.
- procedure Freeze_Subprogram (N : Node_Id) is
- E : constant Entity_Id := Entity (N);
+ Analyze (N);
+
+ if Ekind (Subp) = E_Function then
+ Resolve (N, Etype (Subp));
+ 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
- -- When a primitive is frozen, enter its name in the corresponding
- -- dispatch table. If the DTC_Entity field is not set this is an
- -- overridden primitive that can be ignored. We suppress the
- -- initialization of the dispatch table entry when Java_VM because
- -- the dispatching mechanism is handled internally by the JVM.
-
- if Is_Dispatching_Operation (E)
- and then not Is_Abstract (E)
- and then Present (DTC_Entity (E))
- and then not Is_CPP_Class (Scope (DTC_Entity (E)))
- and then not Java_VM
+ -- 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
- Check_Overriding_Operation (E);
- Insert_After (N, Fill_DT_Entry (Sloc (N), E));
+ -- 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;
+
+ -- In Ada 2005 all functions with an inherently limited return type
+ -- must be handled using a build-in-place profile, including the case
+ -- of a function with a limited interface result, where the function
+ -- may return objects of nonlimited descendants.
+
+ 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;
- -- 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)
+ -------------------------------------
+ -- Is_Build_In_Place_Function_Call --
+ -------------------------------------
- declare
- Typ : constant Entity_Id := Etype (E);
- Utyp : constant Entity_Id := Underlying_Type (Typ);
+ function Is_Build_In_Place_Function_Call (N : Node_Id) return Boolean is
+ Exp_Node : Node_Id := N;
+ Function_Id : Entity_Id;
- begin
- if Is_Return_By_Reference_Type (Typ) then
- Set_Returns_By_Ref (E);
+ 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;
- elsif Present (Utyp) and then Controlled_Type (Utyp) then
- Set_Returns_By_Ref (E);
+ 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;
- end;
+
+ return Is_Build_In_Place_Function (Function_Id);
+ end if;
+ end Is_Build_In_Place_Function_Call;
+
+ -----------------------
+ -- 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 Tagged_Type_Expansion
+ 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;
+
+ Insert_Actions_After (N,
+ Register_Primitive (Loc, Prim => Subp));
+ 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;
+ -----------------------
+ -- Is_Null_Procedure --
+ -----------------------
+
+ function Is_Null_Procedure (Subp : Entity_Id) return Boolean is
+ Decl : constant Node_Id := Unit_Declaration_Node (Subp);
+
+ begin
+ if Ekind (Subp) /= E_Procedure then
+ return False;
+
+ -- Check if this is a declared null procedure
+
+ elsif Nkind (Decl) = N_Subprogram_Declaration then
+ if not Null_Present (Specification (Decl)) then
+ return False;
+
+ elsif No (Body_To_Inline (Decl)) then
+ return False;
+
+ -- Check if the body contains only a null statement, followed by
+ -- the return statement added during expansion.
+
+ else
+ declare
+ Orig_Bod : constant Node_Id := Body_To_Inline (Decl);
+
+ Stat : Node_Id;
+ Stat2 : Node_Id;
+
+ begin
+ if Nkind (Orig_Bod) /= N_Subprogram_Body then
+ return False;
+ else
+ -- We must skip SCIL nodes because they are currently
+ -- implemented as special N_Null_Statement nodes.
+
+ Stat :=
+ First_Non_SCIL_Node
+ (Statements (Handled_Statement_Sequence (Orig_Bod)));
+ Stat2 := Next_Non_SCIL_Node (Stat);
+
+ return
+ Is_Empty_List (Declarations (Orig_Bod))
+ and then Nkind (Stat) = N_Null_Statement
+ and then
+ (No (Stat2)
+ or else
+ (Nkind (Stat2) = N_Simple_Return_Statement
+ and then No (Next (Stat2))));
+ end if;
+ end;
+ end if;
+
+ else
+ return False;
+ end if;
+ end Is_Null_Procedure;
+
+ -------------------------------------------
+ -- 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,
+ Expression => New_Reference_To (Result_Subt, Loc));
+ Set_No_Initialization (New_Allocator);
+
+ -- Copy attributes to new allocator. Note that the new allocator
+ -- logically comes from source if the original one did, so copy the
+ -- relevant flag. This ensures proper treatment of the restriction
+ -- No_Implicit_Heap_Allocations in this case.
+
+ Set_Storage_Pool (New_Allocator, Storage_Pool (Allocator));
+ Set_Procedure_To_Call (New_Allocator, Procedure_To_Call (Allocator));
+ Set_Comes_From_Source (New_Allocator, Comes_From_Source (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);
+ Func_Call : Node_Id := Function_Call;
+ Func_Id : Entity_Id;
+ Loc : Source_Ptr;
+ Obj_Decl : Node_Id;
+ Obj_Id : Entity_Id;
+ Ptr_Typ : Entity_Id;
+ Ptr_Typ_Decl : Node_Id;
+ Result_Subt : Entity_Id;
+ Target : 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
+ Func_Id := Entity (Name (Func_Call));
+
+ elsif Nkind (Name (Func_Call)) = N_Explicit_Dereference then
+ Func_Id := Etype (Name (Func_Call));
+
+ else
+ raise Program_Error;
+ end if;
+
+ Result_Subt := Etype (Func_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, Func_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, Func_Id, Acc_Type => Empty, Sel_Comp => Lhs);
+ else
+ Add_Final_List_Actual_To_Build_In_Place_Call
+ (Func_Call, Func_Id, Acc_Type => Empty);
+ end if;
+
+ Add_Task_Actuals_To_Build_In_Place_Call
+ (Func_Call, Func_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,
+ Func_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
+
+ Ptr_Typ :=
+ Make_Defining_Identifier (Loc, New_Internal_Name ('A'));
+
+ Ptr_Typ_Decl :=
+ Make_Full_Type_Declaration (Loc,
+ Defining_Identifier => Ptr_Typ,
+ 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.
+
+ Obj_Id := Make_Defining_Identifier (Loc, New_Internal_Name ('R'));
+ Set_Etype (Obj_Id, Ptr_Typ);
+
+ Obj_Decl :=
+ Make_Object_Declaration (Loc,
+ Defining_Identifier => Obj_Id,
+ Object_Definition =>
+ New_Reference_To (Ptr_Typ, Loc),
+ Expression =>
+ Make_Reference (Loc,
+ Prefix => Relocate_Node (Func_Call)));
+ Insert_After_And_Analyze (Ptr_Typ_Decl, Obj_Decl);
+
+ Rewrite (Assign, Make_Null_Statement (Loc));
+
+ -- Retrieve the target of the assignment
+
+ if Nkind (Lhs) = N_Selected_Component then
+ Target := Selector_Name (Lhs);
+ elsif Nkind (Lhs) = N_Type_Conversion then
+ Target := Expression (Lhs);
+ else
+ Target := Lhs;
+ end if;
+
+ -- If we are assigning to a return object or this is an expression of
+ -- an extension aggregate, the target should either be an identifier
+ -- or a simple expression. All other cases imply a different scenario.
+
+ if Nkind (Target) in N_Has_Entity then
+ Target := Entity (Target);
+ else
+ return;
+ end if;
+
+ -- When the target of the assignment is a return object of an enclosing
+ -- build-in-place function and also requires finalization, the list
+ -- generated for the assignment must be moved to that of the enclosing
+ -- function.
+
+ -- function Enclosing_BIP_Function return Ctrl_Typ is
+ -- begin
+ -- return (Ctrl_Parent_Part => BIP_Function with ...);
+ -- end Enclosing_BIP_Function;
+
+ if Is_Return_Object (Target)
+ and then Needs_Finalization (Etype (Target))
+ and then Needs_Finalization (Result_Subt)
+ then
+ declare
+ Obj_List : constant Node_Id := Find_Final_List (Obj_Id);
+ Encl_List : Node_Id;
+ Encl_Scop : Entity_Id;
+
+ begin
+ Encl_Scop := Scope (Target);
+
+ -- Locate the scope of the extended return statement
+
+ while Present (Encl_Scop)
+ and then Ekind (Encl_Scop) /= E_Return_Statement
+ loop
+ Encl_Scop := Scope (Encl_Scop);
+ end loop;
+
+ -- A return object should always be enclosed by a return statement
+ -- scope at some level.
+
+ pragma Assert (Present (Encl_Scop));
+
+ Encl_List :=
+ Make_Attribute_Reference (Loc,
+ Prefix =>
+ New_Reference_To (
+ Finalization_Chain_Entity (Encl_Scop), Loc),
+ Attribute_Name => Name_Unrestricted_Access);
+
+ -- Generate a call to move final list
+
+ Insert_After_And_Analyze (Obj_Decl,
+ Make_Procedure_Call_Statement (Loc,
+ Name =>
+ New_Reference_To (RTE (RE_Move_Final_List), Loc),
+ Parameter_Associations => New_List (Obj_List, Encl_List)));
+ end;
+ end if;
+ 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. (Unfortunately, this won't cover
+ -- the case of extension aggregates where the ancestor part is a build-
+ -- in-place unconstrained function call that should be passed along the
+ -- caller's parameters. Currently those get mishandled by reassigning
+ -- the result of the call to the aggregate return object, when the call
+ -- result should really be directly built in place in the aggregate and
+ -- not built in a temporary. ???)
+
+ elsif Is_Return_Object (Defining_Identifier (Object_Decl)) then
+ 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. Finally, the homonym chain must be preserved as well.
+
+ 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);
+ Set_Homonym (Renaming_Def_Id, Homonym (Obj_Def_Id));
+
+ 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;
OSDN Git Service
