------------------------------------------------------------------------------ -- -- -- GNAT COMPILER COMPONENTS -- -- -- -- E X P _ C H 9 -- -- -- -- B o d y -- -- -- -- Copyright (C) 1992-2004, Free Software Foundation, Inc. -- -- -- -- GNAT is free software; you can redistribute it and/or modify it under -- -- terms of the GNU General Public License as published by the Free Soft- -- -- ware Foundation; either version 2, or (at your option) any later ver- -- -- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License -- -- for more details. You should have received a copy of the GNU General -- -- Public License distributed with GNAT; see file COPYING. If not, write -- -- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, -- -- MA 02111-1307, USA. -- -- -- -- GNAT was originally developed by the GNAT team at New York University. -- -- Extensive contributions were provided by Ada Core Technologies Inc. -- -- -- ------------------------------------------------------------------------------ with Atree; use Atree; with Checks; use Checks; with Einfo; use Einfo; with Elists; use Elists; with Errout; use Errout; with Exp_Ch3; use Exp_Ch3; with Exp_Ch11; use Exp_Ch11; with Exp_Ch6; use Exp_Ch6; with Exp_Dbug; use Exp_Dbug; with Exp_Smem; use Exp_Smem; with Exp_Tss; use Exp_Tss; with Exp_Util; use Exp_Util; with Freeze; use Freeze; with Hostparm; with Namet; use Namet; with Nlists; use Nlists; with Nmake; use Nmake; with Opt; use Opt; with Restrict; use Restrict; with Rident; use Rident; with Rtsfind; use Rtsfind; with Sem; use Sem; with Sem_Ch6; with Sem_Ch8; use Sem_Ch8; with Sem_Ch11; use Sem_Ch11; with Sem_Elab; use Sem_Elab; with Sem_Res; use Sem_Res; with Sem_Util; use Sem_Util; with Sinfo; use Sinfo; with Snames; use Snames; with Stand; use Stand; with Targparm; use Targparm; with Tbuild; use Tbuild; with Types; use Types; with Uintp; use Uintp; package body Exp_Ch9 is ----------------------- -- Local Subprograms -- ----------------------- function Actual_Index_Expression (Sloc : Source_Ptr; Ent : Entity_Id; Index : Node_Id; Tsk : Entity_Id) return Node_Id; -- Compute the index position for an entry call. Tsk is the target -- task. If the bounds of some entry family depend on discriminants, -- the expression computed by this function uses the discriminants -- of the target task. function Index_Constant_Declaration (N : Node_Id; Index_Id : Entity_Id; Prot : Entity_Id) return List_Id; -- For an entry family and its barrier function, we define a local entity -- that maps the index in the call into the entry index into the object: -- -- I : constant Index_Type := Index_Type'Val ( -- E - <> + -- Protected_Entry_Index (Index_Type'Pos (Index_Type'First))); procedure Add_Object_Pointer (Decls : List_Id; Pid : Entity_Id; Loc : Source_Ptr); -- Prepend an object pointer declaration to the declaration list -- Decls. This object pointer is initialized to a type conversion -- of the System.Address pointer passed to entry barrier functions -- and entry body procedures. function Build_Accept_Body (Astat : Node_Id) return Node_Id; -- Transform accept statement into a block with added exception handler. -- Used both for simple accept statements and for accept alternatives in -- select statements. Astat is the accept statement. function Build_Barrier_Function (N : Node_Id; Ent : Entity_Id; Pid : Node_Id) return Node_Id; -- Build the function body returning the value of the barrier expression -- for the specified entry body. function Build_Barrier_Function_Specification (Def_Id : Entity_Id; Loc : Source_Ptr) return Node_Id; -- Build a specification for a function implementing -- the protected entry barrier of the specified entry body. function Build_Corresponding_Record (N : Node_Id; Ctyp : Node_Id; Loc : Source_Ptr) return Node_Id; -- Common to tasks and protected types. Copy discriminant specifications, -- build record declaration. N is the type declaration, Ctyp is the -- concurrent entity (task type or protected type). function Build_Entry_Count_Expression (Concurrent_Type : Node_Id; Component_List : List_Id; Loc : Source_Ptr) return Node_Id; -- Compute number of entries for concurrent object. This is a count of -- simple entries, followed by an expression that computes the length -- of the range of each entry family. A single array with that size is -- allocated for each concurrent object of the type. function Build_Find_Body_Index (Typ : Entity_Id) return Node_Id; -- Build the function that translates the entry index in the call -- (which depends on the size of entry families) into an index into the -- Entry_Bodies_Array, to determine the body and barrier function used -- in a protected entry call. A pointer to this function appears in every -- protected object. function Build_Find_Body_Index_Spec (Typ : Entity_Id) return Node_Id; -- Build subprogram declaration for previous one function Build_Protected_Entry (N : Node_Id; Ent : Entity_Id; Pid : Node_Id) return Node_Id; -- Build the procedure implementing the statement sequence of -- the specified entry body. function Build_Protected_Entry_Specification (Def_Id : Entity_Id; Ent_Id : Entity_Id; Loc : Source_Ptr) return Node_Id; -- Build a specification for a procedure implementing -- the statement sequence of the specified entry body. -- Add attributes associating it with the entry defining identifier -- Ent_Id. function Build_Protected_Subprogram_Body (N : Node_Id; Pid : Node_Id; N_Op_Spec : Node_Id) return Node_Id; -- This function is used to construct the protected version of a protected -- subprogram. Its statement sequence first defers abortion, then locks -- the associated protected object, and then enters a block that contains -- a call to the unprotected version of the subprogram (for details, see -- Build_Unprotected_Subprogram_Body). This block statement requires -- a cleanup handler that unlocks the object in all cases. -- (see Exp_Ch7.Expand_Cleanup_Actions). function Build_Protected_Spec (N : Node_Id; Obj_Type : Entity_Id; Unprotected : Boolean := False; Ident : Entity_Id) return List_Id; -- Utility shared by Build_Protected_Sub_Spec and Expand_Access_Protected_ -- Subprogram_Type. Builds signature of protected subprogram, adding the -- formal that corresponds to the object itself. For an access to protected -- subprogram, there is no object type to specify, so the additional -- parameter has type Address and mode In. An indirect call through such -- a pointer converts the address to a reference to the actual object. -- The object is a limited record and therefore a by_reference type. function Build_Selected_Name (Prefix, Selector : Name_Id; Append_Char : Character := ' ') return Name_Id; -- Build a name in the form of Prefix__Selector, with an optional -- character appended. This is used for internal subprograms generated -- for operations of protected types, including barrier functions. -- For the subprograms generated for entry bodies and entry barriers, -- the generated name includes a sequence number that makes names -- unique in the presence of entry overloading. This is necessary -- because entry body procedures and barrier functions all have the -- same signature. procedure Build_Simple_Entry_Call (N : Node_Id; Concval : Node_Id; Ename : Node_Id; Index : Node_Id); -- Some comments here would be useful ??? function Build_Task_Proc_Specification (T : Entity_Id) return Node_Id; -- This routine constructs a specification for the procedure that we will -- build for the task body for task type T. The spec has the form: -- -- procedure tnameB (_Task : access tnameV); -- -- where name is the character name taken from the task type entity that -- is passed as the argument to the procedure, and tnameV is the task -- value type that is associated with the task type. function Build_Unprotected_Subprogram_Body (N : Node_Id; Pid : Node_Id) return Node_Id; -- This routine constructs the unprotected version of a protected -- subprogram body, which is contains all of the code in the -- original, unexpanded body. This is the version of the protected -- subprogram that is called from all protected operations on the same -- object, including the protected version of the same subprogram. procedure Collect_Entry_Families (Loc : Source_Ptr; Cdecls : List_Id; Current_Node : in out Node_Id; Conctyp : Entity_Id); -- For each entry family in a concurrent type, create an anonymous array -- type of the right size, and add a component to the corresponding_record. function Family_Offset (Loc : Source_Ptr; Hi : Node_Id; Lo : Node_Id; Ttyp : Entity_Id) return Node_Id; -- Compute (Hi - Lo) for two entry family indices. Hi is the index in -- an accept statement, or the upper bound in the discrete subtype of -- an entry declaration. Lo is the corresponding lower bound. Ttyp is -- the concurrent type of the entry. function Family_Size (Loc : Source_Ptr; Hi : Node_Id; Lo : Node_Id; Ttyp : Entity_Id) return Node_Id; -- Compute (Hi - Lo) + 1 Max 0, to determine the number of entries in -- a family, and handle properly the superflat case. This is equivalent -- to the use of 'Length on the index type, but must use Family_Offset -- to handle properly the case of bounds that depend on discriminants. procedure Extract_Entry (N : Node_Id; Concval : out Node_Id; Ename : out Node_Id; Index : out Node_Id); -- Given an entry call, returns the associated concurrent object, -- the entry name, and the entry family index. function Find_Task_Or_Protected_Pragma (T : Node_Id; P : Name_Id) return Node_Id; -- Searches the task or protected definition T for the first occurrence -- of the pragma whose name is given by P. The caller has ensured that -- the pragma is present in the task definition. A special case is that -- when P is Name_uPriority, the call will also find Interrupt_Priority. -- ??? Should be implemented with the rep item chain mechanism. procedure Update_Prival_Subtypes (N : Node_Id); -- The actual subtypes of the privals will differ from the type of the -- private declaration in the original protected type, if the protected -- type has discriminants or if the prival has constrained components. -- This is because the privals are generated out of sequence w.r.t. the -- analysis of a protected body. After generating the bodies for protected -- operations, we set correctly the type of all references to privals, by -- means of a recursive tree traversal, which is heavy-handed but -- correct. ----------------------------- -- Actual_Index_Expression -- ----------------------------- function Actual_Index_Expression (Sloc : Source_Ptr; Ent : Entity_Id; Index : Node_Id; Tsk : Entity_Id) return Node_Id is Ttyp : constant Entity_Id := Etype (Tsk); Expr : Node_Id; Num : Node_Id; Lo : Node_Id; Hi : Node_Id; Prev : Entity_Id; S : Node_Id; function Actual_Family_Offset (Hi, Lo : Node_Id) return Node_Id; -- Compute difference between bounds of entry family -------------------------- -- Actual_Family_Offset -- -------------------------- function Actual_Family_Offset (Hi, Lo : Node_Id) return Node_Id is function Actual_Discriminant_Ref (Bound : Node_Id) return Node_Id; -- Replace a reference to a discriminant with a selected component -- denoting the discriminant of the target task. ----------------------------- -- Actual_Discriminant_Ref -- ----------------------------- function Actual_Discriminant_Ref (Bound : Node_Id) return Node_Id is Typ : constant Entity_Id := Etype (Bound); B : Node_Id; begin if not Is_Entity_Name (Bound) or else Ekind (Entity (Bound)) /= E_Discriminant then if Nkind (Bound) = N_Attribute_Reference then return Bound; else B := New_Copy_Tree (Bound); end if; else B := Make_Selected_Component (Sloc, Prefix => New_Copy_Tree (Tsk), Selector_Name => New_Occurrence_Of (Entity (Bound), Sloc)); Analyze_And_Resolve (B, Typ); end if; return Make_Attribute_Reference (Sloc, Attribute_Name => Name_Pos, Prefix => New_Occurrence_Of (Etype (Bound), Sloc), Expressions => New_List (B)); end Actual_Discriminant_Ref; -- Start of processing for Actual_Family_Offset begin return Make_Op_Subtract (Sloc, Left_Opnd => Actual_Discriminant_Ref (Hi), Right_Opnd => Actual_Discriminant_Ref (Lo)); end Actual_Family_Offset; -- Start of processing for Actual_Index_Expression begin -- The queues of entries and entry families appear in textual -- order in the associated record. The entry index is computed as -- the sum of the number of queues for all entries that precede the -- designated one, to which is added the index expression, if this -- expression denotes a member of a family. -- The following is a place holder for the count of simple entries Num := Make_Integer_Literal (Sloc, 1); -- We construct an expression which is a series of addition -- operations. See comments in Entry_Index_Expression, which is -- identical in structure. if Present (Index) then S := Etype (Discrete_Subtype_Definition (Declaration_Node (Ent))); Expr := Make_Op_Add (Sloc, Left_Opnd => Num, Right_Opnd => Actual_Family_Offset ( Make_Attribute_Reference (Sloc, Attribute_Name => Name_Pos, Prefix => New_Reference_To (Base_Type (S), Sloc), Expressions => New_List (Relocate_Node (Index))), Type_Low_Bound (S))); else Expr := Num; end if; -- Now add lengths of preceding entries and entry families Prev := First_Entity (Ttyp); while Chars (Prev) /= Chars (Ent) or else (Ekind (Prev) /= Ekind (Ent)) or else not Sem_Ch6.Type_Conformant (Ent, Prev) loop if Ekind (Prev) = E_Entry then Set_Intval (Num, Intval (Num) + 1); elsif Ekind (Prev) = E_Entry_Family then S := Etype (Discrete_Subtype_Definition (Declaration_Node (Prev))); Lo := Type_Low_Bound (S); Hi := Type_High_Bound (S); Expr := Make_Op_Add (Sloc, Left_Opnd => Expr, Right_Opnd => Make_Op_Add (Sloc, Left_Opnd => Actual_Family_Offset (Hi, Lo), Right_Opnd => Make_Integer_Literal (Sloc, 1))); -- Other components are anonymous types to be ignored else null; end if; Next_Entity (Prev); end loop; return Expr; end Actual_Index_Expression; ---------------------------------- -- Add_Discriminal_Declarations -- ---------------------------------- procedure Add_Discriminal_Declarations (Decls : List_Id; Typ : Entity_Id; Name : Name_Id; Loc : Source_Ptr) is D : Entity_Id; begin if Has_Discriminants (Typ) then D := First_Discriminant (Typ); while Present (D) loop Prepend_To (Decls, Make_Object_Renaming_Declaration (Loc, Defining_Identifier => Discriminal (D), Subtype_Mark => New_Reference_To (Etype (D), Loc), Name => Make_Selected_Component (Loc, Prefix => Make_Identifier (Loc, Name), Selector_Name => Make_Identifier (Loc, Chars (D))))); Next_Discriminant (D); end loop; end if; end Add_Discriminal_Declarations; ------------------------ -- Add_Object_Pointer -- ------------------------ procedure Add_Object_Pointer (Decls : List_Id; Pid : Entity_Id; Loc : Source_Ptr) is Obj_Ptr : Node_Id; begin -- Prepend the declaration of _object. This must be first in the -- declaration list, since it is used by the discriminal and -- prival declarations. -- ??? An attempt to make this a renaming was unsuccessful. -- -- type poVP is access poV; -- _object : poVP := poVP!O; Obj_Ptr := Make_Defining_Identifier (Loc, Chars => New_External_Name (Chars (Corresponding_Record_Type (Pid)), 'P')); Prepend_To (Decls, Make_Object_Declaration (Loc, Defining_Identifier => Make_Defining_Identifier (Loc, Name_uObject), Object_Definition => New_Reference_To (Obj_Ptr, Loc), Expression => Unchecked_Convert_To (Obj_Ptr, Make_Identifier (Loc, Name_uO)))); Prepend_To (Decls, Make_Full_Type_Declaration (Loc, Defining_Identifier => Obj_Ptr, Type_Definition => Make_Access_To_Object_Definition (Loc, Subtype_Indication => New_Reference_To (Corresponding_Record_Type (Pid), Loc)))); end Add_Object_Pointer; ------------------------------ -- Add_Private_Declarations -- ------------------------------ procedure Add_Private_Declarations (Decls : List_Id; Typ : Entity_Id; Name : Name_Id; Loc : Source_Ptr) is Def : constant Node_Id := Protected_Definition (Parent (Typ)); Body_Ent : constant Entity_Id := Corresponding_Body (Parent (Typ)); P : Node_Id; Pdef : Entity_Id; begin pragma Assert (Nkind (Def) = N_Protected_Definition); if Present (Private_Declarations (Def)) then P := First (Private_Declarations (Def)); while Present (P) loop if Nkind (P) = N_Component_Declaration then Pdef := Defining_Identifier (P); Prepend_To (Decls, Make_Object_Renaming_Declaration (Loc, Defining_Identifier => Prival (Pdef), Subtype_Mark => New_Reference_To (Etype (Pdef), Loc), Name => Make_Selected_Component (Loc, Prefix => Make_Identifier (Loc, Name), Selector_Name => Make_Identifier (Loc, Chars (Pdef))))); end if; Next (P); end loop; end if; -- One more "prival" for the object itself, with the right protection -- type. declare Protection_Type : RE_Id; begin if Has_Attach_Handler (Typ) then if Restricted_Profile then if Has_Entries (Typ) then Protection_Type := RE_Protection_Entry; else Protection_Type := RE_Protection; end if; else Protection_Type := RE_Static_Interrupt_Protection; end if; elsif Has_Interrupt_Handler (Typ) then Protection_Type := RE_Dynamic_Interrupt_Protection; elsif Has_Entries (Typ) then if Abort_Allowed or else Restriction_Active (No_Entry_Queue) = False or else Number_Entries (Typ) > 1 then Protection_Type := RE_Protection_Entries; else Protection_Type := RE_Protection_Entry; end if; else Protection_Type := RE_Protection; end if; Prepend_To (Decls, Make_Object_Renaming_Declaration (Loc, Defining_Identifier => Object_Ref (Body_Ent), Subtype_Mark => New_Reference_To (RTE (Protection_Type), Loc), Name => Make_Selected_Component (Loc, Prefix => Make_Identifier (Loc, Name), Selector_Name => Make_Identifier (Loc, Name_uObject)))); end; end Add_Private_Declarations; ----------------------- -- Build_Accept_Body -- ----------------------- function Build_Accept_Body (Astat : Node_Id) return Node_Id is Loc : constant Source_Ptr := Sloc (Astat); Stats : constant Node_Id := Handled_Statement_Sequence (Astat); New_S : Node_Id; Hand : Node_Id; Call : Node_Id; Ohandle : Node_Id; begin -- At the end of the statement sequence, Complete_Rendezvous is called. -- A label skipping the Complete_Rendezvous, and all other -- accept processing, has already been added for the expansion -- of requeue statements. Call := Build_Runtime_Call (Loc, RE_Complete_Rendezvous); Insert_Before (Last (Statements (Stats)), Call); Analyze (Call); -- If exception handlers are present, then append Complete_Rendezvous -- calls to the handlers, and construct the required outer block. if Present (Exception_Handlers (Stats)) then Hand := First (Exception_Handlers (Stats)); while Present (Hand) loop Call := Build_Runtime_Call (Loc, RE_Complete_Rendezvous); Append (Call, Statements (Hand)); Analyze (Call); Next (Hand); end loop; New_S := Make_Handled_Sequence_Of_Statements (Loc, Statements => New_List ( Make_Block_Statement (Loc, Handled_Statement_Sequence => Stats))); else New_S := Stats; end if; -- At this stage we know that the new statement sequence does not -- have an exception handler part, so we supply one to call -- Exceptional_Complete_Rendezvous. This handler is -- when all others => -- Exceptional_Complete_Rendezvous (Get_GNAT_Exception); -- We handle Abort_Signal to make sure that we properly catch the abort -- case and wake up the caller. Ohandle := Make_Others_Choice (Loc); Set_All_Others (Ohandle); Set_Exception_Handlers (New_S, New_List ( Make_Exception_Handler (Loc, Exception_Choices => New_List (Ohandle), Statements => New_List ( Make_Procedure_Call_Statement (Loc, Name => New_Reference_To ( RTE (RE_Exceptional_Complete_Rendezvous), Loc), Parameter_Associations => New_List ( Make_Function_Call (Loc, Name => New_Reference_To ( RTE (RE_Get_GNAT_Exception), Loc)))))))); Set_Parent (New_S, Astat); -- temp parent for Analyze call Analyze_Exception_Handlers (Exception_Handlers (New_S)); Expand_Exception_Handlers (New_S); -- Exceptional_Complete_Rendezvous must be called with abort -- still deferred, which is the case for a "when all others" handler. return New_S; end Build_Accept_Body; ----------------------------------- -- Build_Activation_Chain_Entity -- ----------------------------------- procedure Build_Activation_Chain_Entity (N : Node_Id) is P : Node_Id; B : Node_Id; Decls : List_Id; begin -- Loop to find enclosing construct containing activation chain variable P := Parent (N); while Nkind (P) /= N_Subprogram_Body and then Nkind (P) /= N_Package_Declaration and then Nkind (P) /= N_Package_Body and then Nkind (P) /= N_Block_Statement and then Nkind (P) /= N_Task_Body loop P := Parent (P); end loop; -- If we are in a package body, the activation chain variable is -- allocated in the corresponding spec. First, we save the package -- body node because we enter the new entity in its Declarations list. B := P; if Nkind (P) = N_Package_Body then P := Unit_Declaration_Node (Corresponding_Spec (P)); Decls := Declarations (B); elsif Nkind (P) = N_Package_Declaration then Decls := Visible_Declarations (Specification (B)); else Decls := Declarations (B); end if; -- If activation chain entity not already declared, declare it if No (Activation_Chain_Entity (P)) then Set_Activation_Chain_Entity (P, Make_Defining_Identifier (Sloc (N), Name_uChain)); Prepend_To (Decls, Make_Object_Declaration (Sloc (P), Defining_Identifier => Activation_Chain_Entity (P), Aliased_Present => True, Object_Definition => New_Reference_To (RTE (RE_Activation_Chain), Sloc (P)))); Analyze (First (Decls)); end if; end Build_Activation_Chain_Entity; ---------------------------- -- Build_Barrier_Function -- ---------------------------- function Build_Barrier_Function (N : Node_Id; Ent : Entity_Id; Pid : Node_Id) return Node_Id is Loc : constant Source_Ptr := Sloc (N); Ent_Formals : constant Node_Id := Entry_Body_Formal_Part (N); Index_Spec : constant Node_Id := Entry_Index_Specification (Ent_Formals); Op_Decls : constant List_Id := New_List; Bdef : Entity_Id; Bspec : Node_Id; begin Bdef := Make_Defining_Identifier (Loc, Chars (Barrier_Function (Ent))); Bspec := Build_Barrier_Function_Specification (Bdef, Loc); -- -- -- -- Add discriminal and private renamings. These names have -- already been used to expand references to discriminants -- and private data. Add_Discriminal_Declarations (Op_Decls, Pid, Name_uObject, Loc); Add_Private_Declarations (Op_Decls, Pid, Name_uObject, Loc); Add_Object_Pointer (Op_Decls, Pid, Loc); -- If this is the barrier for an entry family, the entry index is -- visible in the body of the barrier. Create a local variable that -- converts the entry index (which is the last formal of the barrier -- function) into the appropriate offset into the entry array. The -- entry index constant must be set, as for the entry body, so that -- local references to the entry index are correctly replaced with -- the local variable. This parallels what is done for entry bodies. if Present (Index_Spec) then declare Index_Id : constant Entity_Id := Defining_Identifier (Index_Spec); Index_Con : constant Entity_Id := Make_Defining_Identifier (Loc, Chars => New_Internal_Name ('J')); begin Set_Entry_Index_Constant (Index_Id, Index_Con); Append_List_To (Op_Decls, Index_Constant_Declaration (N, Index_Id, Pid)); end; end if; -- Note: the condition in the barrier function needs to be properly -- processed for the C/Fortran boolean possibility, but this happens -- automatically since the return statement does this normalization. return Make_Subprogram_Body (Loc, Specification => Bspec, Declarations => Op_Decls, Handled_Statement_Sequence => Make_Handled_Sequence_Of_Statements (Loc, Statements => New_List ( Make_Return_Statement (Loc, Expression => Condition (Ent_Formals))))); end Build_Barrier_Function; ------------------------------------------ -- Build_Barrier_Function_Specification -- ------------------------------------------ function Build_Barrier_Function_Specification (Def_Id : Entity_Id; Loc : Source_Ptr) return Node_Id is begin Set_Needs_Debug_Info (Def_Id); return Make_Function_Specification (Loc, Defining_Unit_Name => Def_Id, Parameter_Specifications => New_List ( Make_Parameter_Specification (Loc, Defining_Identifier => Make_Defining_Identifier (Loc, Name_uO), Parameter_Type => New_Reference_To (RTE (RE_Address), Loc)), Make_Parameter_Specification (Loc, Defining_Identifier => Make_Defining_Identifier (Loc, Name_uE), Parameter_Type => New_Reference_To (RTE (RE_Protected_Entry_Index), Loc))), Subtype_Mark => New_Reference_To (Standard_Boolean, Loc)); end Build_Barrier_Function_Specification; -------------------------- -- Build_Call_With_Task -- -------------------------- function Build_Call_With_Task (N : Node_Id; E : Entity_Id) return Node_Id is Loc : constant Source_Ptr := Sloc (N); begin return Make_Function_Call (Loc, Name => New_Reference_To (E, Loc), Parameter_Associations => New_List (Concurrent_Ref (N))); end Build_Call_With_Task; -------------------------------- -- Build_Corresponding_Record -- -------------------------------- function Build_Corresponding_Record (N : Node_Id; Ctyp : Entity_Id; Loc : Source_Ptr) return Node_Id is Rec_Ent : constant Entity_Id := Make_Defining_Identifier (Loc, New_External_Name (Chars (Ctyp), 'V')); Disc : Entity_Id; Dlist : List_Id; New_Disc : Entity_Id; Cdecls : List_Id; begin Set_Corresponding_Record_Type (Ctyp, Rec_Ent); Set_Ekind (Rec_Ent, E_Record_Type); Set_Has_Delayed_Freeze (Rec_Ent, Has_Delayed_Freeze (Ctyp)); Set_Is_Concurrent_Record_Type (Rec_Ent, True); Set_Corresponding_Concurrent_Type (Rec_Ent, Ctyp); Set_Stored_Constraint (Rec_Ent, No_Elist); Cdecls := New_List; -- Use discriminals to create list of discriminants for record, and -- create new discriminals for use in default expressions, etc. It is -- worth noting that a task discriminant gives rise to 5 entities; -- a) The original discriminant. -- b) The discriminal for use in the task. -- c) The discriminant of the corresponding record. -- d) The discriminal for the init proc of the corresponding record. -- e) The local variable that renames the discriminant in the procedure -- for the task body. -- In fact the discriminals b) are used in the renaming declarations -- for e). See details in einfo (Handling of Discriminants). if Present (Discriminant_Specifications (N)) then Dlist := New_List; Disc := First_Discriminant (Ctyp); while Present (Disc) loop New_Disc := CR_Discriminant (Disc); Append_To (Dlist, Make_Discriminant_Specification (Loc, Defining_Identifier => New_Disc, Discriminant_Type => New_Occurrence_Of (Etype (Disc), Loc), Expression => New_Copy (Discriminant_Default_Value (Disc)))); Next_Discriminant (Disc); end loop; else Dlist := No_List; end if; -- Now we can construct the record type declaration. Note that this -- record is limited, reflecting the underlying limitedness of the -- task or protected object that it represents, and ensuring for -- example that it is properly passed by reference. return Make_Full_Type_Declaration (Loc, Defining_Identifier => Rec_Ent, Discriminant_Specifications => Dlist, Type_Definition => Make_Record_Definition (Loc, Component_List => Make_Component_List (Loc, Component_Items => Cdecls), Limited_Present => True)); end Build_Corresponding_Record; ---------------------------------- -- Build_Entry_Count_Expression -- ---------------------------------- function Build_Entry_Count_Expression (Concurrent_Type : Node_Id; Component_List : List_Id; Loc : Source_Ptr) return Node_Id is Eindx : Nat; Ent : Entity_Id; Ecount : Node_Id; Comp : Node_Id; Lo : Node_Id; Hi : Node_Id; Typ : Entity_Id; begin Ent := First_Entity (Concurrent_Type); Eindx := 0; -- Count number of non-family entries while Present (Ent) loop if Ekind (Ent) = E_Entry then Eindx := Eindx + 1; end if; Next_Entity (Ent); end loop; Ecount := Make_Integer_Literal (Loc, Eindx); -- Loop through entry families building the addition nodes Ent := First_Entity (Concurrent_Type); Comp := First (Component_List); while Present (Ent) loop if Ekind (Ent) = E_Entry_Family then while Chars (Ent) /= Chars (Defining_Identifier (Comp)) loop Next (Comp); end loop; Typ := Etype (Discrete_Subtype_Definition (Parent (Ent))); Hi := Type_High_Bound (Typ); Lo := Type_Low_Bound (Typ); Ecount := Make_Op_Add (Loc, Left_Opnd => Ecount, Right_Opnd => Family_Size (Loc, Hi, Lo, Concurrent_Type)); end if; Next_Entity (Ent); end loop; return Ecount; end Build_Entry_Count_Expression; --------------------------- -- Build_Find_Body_Index -- --------------------------- function Build_Find_Body_Index (Typ : Entity_Id) return Node_Id is Loc : constant Source_Ptr := Sloc (Typ); Ent : Entity_Id; E_Typ : Entity_Id; Has_F : Boolean := False; Index : Nat; If_St : Node_Id := Empty; Lo : Node_Id; Hi : Node_Id; Decls : List_Id := New_List; Ret : Node_Id; Spec : Node_Id; Siz : Node_Id := Empty; procedure Add_If_Clause (Expr : Node_Id); -- Add test for range of current entry function Convert_Discriminant_Ref (Bound : Node_Id) return Node_Id; -- If a bound of an entry is given by a discriminant, retrieve the -- actual value of the discriminant from the enclosing object. ------------------- -- Add_If_Clause -- ------------------- procedure Add_If_Clause (Expr : Node_Id) is Cond : Node_Id; Stats : constant List_Id := New_List ( Make_Return_Statement (Loc, Expression => Make_Integer_Literal (Loc, Index + 1))); begin -- Index for current entry body Index := Index + 1; -- Compute total length of entry queues so far if No (Siz) then Siz := Expr; else Siz := Make_Op_Add (Loc, Left_Opnd => Siz, Right_Opnd => Expr); end if; Cond := Make_Op_Le (Loc, Left_Opnd => Make_Identifier (Loc, Name_uE), Right_Opnd => Siz); -- Map entry queue indices in the range of the current family -- into the current index, that designates the entry body. if No (If_St) then If_St := Make_Implicit_If_Statement (Typ, Condition => Cond, Then_Statements => Stats, Elsif_Parts => New_List); Ret := If_St; else Append ( Make_Elsif_Part (Loc, Condition => Cond, Then_Statements => Stats), Elsif_Parts (If_St)); end if; end Add_If_Clause; ------------------------------ -- Convert_Discriminant_Ref -- ------------------------------ function Convert_Discriminant_Ref (Bound : Node_Id) return Node_Id is B : Node_Id; begin if Is_Entity_Name (Bound) and then Ekind (Entity (Bound)) = E_Discriminant then B := Make_Selected_Component (Loc, Prefix => Unchecked_Convert_To (Corresponding_Record_Type (Typ), Make_Explicit_Dereference (Loc, Make_Identifier (Loc, Name_uObject))), Selector_Name => Make_Identifier (Loc, Chars (Bound))); Set_Etype (B, Etype (Entity (Bound))); else B := New_Copy_Tree (Bound); end if; return B; end Convert_Discriminant_Ref; -- Start of processing for Build_Find_Body_Index begin Spec := Build_Find_Body_Index_Spec (Typ); Ent := First_Entity (Typ); while Present (Ent) loop if Ekind (Ent) = E_Entry_Family then Has_F := True; exit; end if; Next_Entity (Ent); end loop; if not Has_F then -- If the protected type has no entry families, there is a one-one -- correspondence between entry queue and entry body. Ret := Make_Return_Statement (Loc, Expression => Make_Identifier (Loc, Name_uE)); else -- Suppose entries e1, e2, ... have size l1, l2, ... we generate -- the following: -- -- if E <= l1 then return 1; -- elsif E <= l1 + l2 then return 2; -- ... Index := 0; Siz := Empty; Ent := First_Entity (Typ); Add_Object_Pointer (Decls, Typ, Loc); while Present (Ent) loop if Ekind (Ent) = E_Entry then Add_If_Clause (Make_Integer_Literal (Loc, 1)); elsif Ekind (Ent) = E_Entry_Family then E_Typ := Etype (Discrete_Subtype_Definition (Parent (Ent))); Hi := Convert_Discriminant_Ref (Type_High_Bound (E_Typ)); Lo := Convert_Discriminant_Ref (Type_Low_Bound (E_Typ)); Add_If_Clause (Family_Size (Loc, Hi, Lo, Typ)); end if; Next_Entity (Ent); end loop; if Index = 1 then Decls := New_List; Ret := Make_Return_Statement (Loc, Expression => Make_Integer_Literal (Loc, 1)); elsif Nkind (Ret) = N_If_Statement then -- Ranges are in increasing order, so last one doesn't need a -- guard. declare Nod : constant Node_Id := Last (Elsif_Parts (Ret)); begin Remove (Nod); Set_Else_Statements (Ret, Then_Statements (Nod)); end; end if; end if; return Make_Subprogram_Body (Loc, Specification => Spec, Declarations => Decls, Handled_Statement_Sequence => Make_Handled_Sequence_Of_Statements (Loc, Statements => New_List (Ret))); end Build_Find_Body_Index; -------------------------------- -- Build_Find_Body_Index_Spec -- -------------------------------- function Build_Find_Body_Index_Spec (Typ : Entity_Id) return Node_Id is Loc : constant Source_Ptr := Sloc (Typ); Id : constant Entity_Id := Make_Defining_Identifier (Loc, Chars => New_External_Name (Chars (Typ), 'F')); Parm1 : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uO); Parm2 : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uE); begin return Make_Function_Specification (Loc, Defining_Unit_Name => Id, Parameter_Specifications => New_List ( Make_Parameter_Specification (Loc, Defining_Identifier => Parm1, Parameter_Type => New_Reference_To (RTE (RE_Address), Loc)), Make_Parameter_Specification (Loc, Defining_Identifier => Parm2, Parameter_Type => New_Reference_To (RTE (RE_Protected_Entry_Index), Loc))), Subtype_Mark => New_Occurrence_Of ( RTE (RE_Protected_Entry_Index), Loc)); end Build_Find_Body_Index_Spec; ------------------------- -- Build_Master_Entity -- ------------------------- procedure Build_Master_Entity (E : Entity_Id) is Loc : constant Source_Ptr := Sloc (E); P : Node_Id; Decl : Node_Id; S : Entity_Id; begin S := Scope (E); -- Ada 2005 (AI-287): Do not set/get the has_master_entity reminder -- in internal scopes. Required for nested limited aggregates. if Ada_Version >= Ada_05 then while Is_Internal (S) loop S := Scope (S); end loop; end if; -- Nothing to do if we already built a master entity for this scope -- or if there is no task hierarchy. if Has_Master_Entity (S) or else Restriction_Active (No_Task_Hierarchy) then return; end if; -- Otherwise first build the master entity -- _Master : constant Master_Id := Current_Master.all; -- and insert it just before the current declaration Decl := Make_Object_Declaration (Loc, Defining_Identifier => Make_Defining_Identifier (Loc, Name_uMaster), Constant_Present => True, Object_Definition => New_Reference_To (RTE (RE_Master_Id), Loc), Expression => Make_Explicit_Dereference (Loc, New_Reference_To (RTE (RE_Current_Master), Loc))); P := Parent (E); Insert_Before (P, Decl); Analyze (Decl); -- Ada 2005 (AI-287): Set the has_master_entity reminder in the -- non-internal scope selected above. if Ada_Version >= Ada_05 then Set_Has_Master_Entity (S); else Set_Has_Master_Entity (Scope (E)); end if; -- Now mark the containing scope as a task master while Nkind (P) /= N_Compilation_Unit loop P := Parent (P); -- If we fall off the top, we are at the outer level, and the -- environment task is our effective master, so nothing to mark. if Nkind (P) = N_Task_Body or else Nkind (P) = N_Block_Statement or else Nkind (P) = N_Subprogram_Body then Set_Is_Task_Master (P, True); return; elsif Nkind (Parent (P)) = N_Subunit then P := Corresponding_Stub (Parent (P)); end if; end loop; end Build_Master_Entity; --------------------------- -- Build_Protected_Entry -- --------------------------- function Build_Protected_Entry (N : Node_Id; Ent : Entity_Id; Pid : Node_Id) return Node_Id is Loc : constant Source_Ptr := Sloc (N); Op_Decls : constant List_Id := New_List; Edef : Entity_Id; Espec : Node_Id; Op_Stats : List_Id; Ohandle : Node_Id; Complete : Node_Id; begin Edef := Make_Defining_Identifier (Loc, Chars => Chars (Protected_Body_Subprogram (Ent))); Espec := Build_Protected_Entry_Specification (Edef, Empty, Loc); -- -- Add object pointer declaration. This is needed by the -- discriminal and prival renamings, which should already -- have been inserted into the declaration list. Add_Object_Pointer (Op_Decls, Pid, Loc); if Abort_Allowed or else Restriction_Active (No_Entry_Queue) = False or else Number_Entries (Pid) > 1 then Complete := New_Reference_To (RTE (RE_Complete_Entry_Body), Loc); else Complete := New_Reference_To (RTE (RE_Complete_Single_Entry_Body), Loc); end if; Op_Stats := New_List ( Make_Block_Statement (Loc, Declarations => Declarations (N), Handled_Statement_Sequence => Handled_Statement_Sequence (N)), Make_Procedure_Call_Statement (Loc, Name => Complete, Parameter_Associations => New_List ( Make_Attribute_Reference (Loc, Prefix => Make_Selected_Component (Loc, Prefix => Make_Identifier (Loc, Name_uObject), Selector_Name => Make_Identifier (Loc, Name_uObject)), Attribute_Name => Name_Unchecked_Access)))); if Restriction_Active (No_Exception_Handlers) then return Make_Subprogram_Body (Loc, Specification => Espec, Declarations => Op_Decls, Handled_Statement_Sequence => Make_Handled_Sequence_Of_Statements (Loc, Op_Stats)); else Ohandle := Make_Others_Choice (Loc); Set_All_Others (Ohandle); if Abort_Allowed or else Restriction_Active (No_Entry_Queue) = False or else Number_Entries (Pid) > 1 then Complete := New_Reference_To (RTE (RE_Exceptional_Complete_Entry_Body), Loc); else Complete := New_Reference_To ( RTE (RE_Exceptional_Complete_Single_Entry_Body), Loc); end if; return Make_Subprogram_Body (Loc, Specification => Espec, Declarations => Op_Decls, Handled_Statement_Sequence => Make_Handled_Sequence_Of_Statements (Loc, Statements => Op_Stats, Exception_Handlers => New_List ( Make_Exception_Handler (Loc, Exception_Choices => New_List (Ohandle), Statements => New_List ( Make_Procedure_Call_Statement (Loc, Name => Complete, Parameter_Associations => New_List ( Make_Attribute_Reference (Loc, Prefix => Make_Selected_Component (Loc, Prefix => Make_Identifier (Loc, Name_uObject), Selector_Name => Make_Identifier (Loc, Name_uObject)), Attribute_Name => Name_Unchecked_Access), Make_Function_Call (Loc, Name => New_Reference_To ( RTE (RE_Get_GNAT_Exception), Loc))))))))); end if; end Build_Protected_Entry; ----------------------------------------- -- Build_Protected_Entry_Specification -- ----------------------------------------- function Build_Protected_Entry_Specification (Def_Id : Entity_Id; Ent_Id : Entity_Id; Loc : Source_Ptr) return Node_Id is P : Entity_Id; begin Set_Needs_Debug_Info (Def_Id); P := Make_Defining_Identifier (Loc, Name_uP); if Present (Ent_Id) then Append_Elmt (P, Accept_Address (Ent_Id)); end if; return Make_Procedure_Specification (Loc, Defining_Unit_Name => Def_Id, Parameter_Specifications => New_List ( Make_Parameter_Specification (Loc, Defining_Identifier => Make_Defining_Identifier (Loc, Name_uO), Parameter_Type => New_Reference_To (RTE (RE_Address), Loc)), Make_Parameter_Specification (Loc, Defining_Identifier => P, Parameter_Type => New_Reference_To (RTE (RE_Address), Loc)), Make_Parameter_Specification (Loc, Defining_Identifier => Make_Defining_Identifier (Loc, Name_uE), Parameter_Type => New_Reference_To (RTE (RE_Protected_Entry_Index), Loc)))); end Build_Protected_Entry_Specification; -------------------------- -- Build_Protected_Spec -- -------------------------- function Build_Protected_Spec (N : Node_Id; Obj_Type : Entity_Id; Unprotected : Boolean := False; Ident : Entity_Id) return List_Id is Loc : constant Source_Ptr := Sloc (N); Formal : Entity_Id; New_Plist : List_Id; New_Param : Node_Id; begin New_Plist := New_List; Formal := First_Formal (Ident); while Present (Formal) loop New_Param := Make_Parameter_Specification (Loc, Defining_Identifier => Make_Defining_Identifier (Sloc (Formal), Chars (Formal)), In_Present => In_Present (Parent (Formal)), Out_Present => Out_Present (Parent (Formal)), Parameter_Type => New_Reference_To (Etype (Formal), Loc)); if Unprotected then Set_Protected_Formal (Formal, Defining_Identifier (New_Param)); end if; Append (New_Param, New_Plist); Next_Formal (Formal); end loop; -- If the subprogram is a procedure and the context is not an access -- to protected subprogram, the parameter is in-out. Otherwise it is -- an in parameter. Prepend_To (New_Plist, Make_Parameter_Specification (Loc, Defining_Identifier => Make_Defining_Identifier (Loc, Name_uObject), In_Present => True, Out_Present => (Etype (Ident) = Standard_Void_Type and then not Is_RTE (Obj_Type, RE_Address)), Parameter_Type => New_Reference_To (Obj_Type, Loc))); return New_Plist; end Build_Protected_Spec; --------------------------------------- -- Build_Protected_Sub_Specification -- --------------------------------------- function Build_Protected_Sub_Specification (N : Node_Id; Prottyp : Entity_Id; Unprotected : Boolean := False) return Node_Id is Loc : constant Source_Ptr := Sloc (N); Decl : Node_Id; Protnm : constant Name_Id := Chars (Prottyp); Ident : Entity_Id; Nam : Name_Id; New_Id : Entity_Id; New_Plist : List_Id; Append_Char : Character; New_Spec : Node_Id; begin if Ekind (Defining_Unit_Name (Specification (N))) = E_Subprogram_Body then Decl := Unit_Declaration_Node (Corresponding_Spec (N)); else Decl := N; end if; Ident := Defining_Unit_Name (Specification (Decl)); Nam := Chars (Ident); New_Plist := Build_Protected_Spec (Decl, Corresponding_Record_Type (Prottyp), Unprotected, Ident); if Unprotected then Append_Char := 'N'; else Append_Char := 'P'; end if; New_Id := Make_Defining_Identifier (Loc, Chars => Build_Selected_Name (Protnm, Nam, Append_Char)); -- The unprotected operation carries the user code, and debugging -- information must be generated for it, even though this spec does -- not come from source. It is also convenient to allow gdb to step -- into the protected operation, even though it only contains lock/ -- unlock calls. Set_Needs_Debug_Info (New_Id); if Nkind (Specification (Decl)) = N_Procedure_Specification then return Make_Procedure_Specification (Loc, Defining_Unit_Name => New_Id, Parameter_Specifications => New_Plist); else New_Spec := Make_Function_Specification (Loc, Defining_Unit_Name => New_Id, Parameter_Specifications => New_Plist, Subtype_Mark => New_Copy (Subtype_Mark (Specification (Decl)))); Set_Return_Present (Defining_Unit_Name (New_Spec)); return New_Spec; end if; end Build_Protected_Sub_Specification; ------------------------------------- -- Build_Protected_Subprogram_Body -- ------------------------------------- function Build_Protected_Subprogram_Body (N : Node_Id; Pid : Node_Id; N_Op_Spec : Node_Id) return Node_Id is Loc : constant Source_Ptr := Sloc (N); Op_Spec : Node_Id; P_Op_Spec : Node_Id; Uactuals : List_Id; Pformal : Node_Id; Unprot_Call : Node_Id; Sub_Body : Node_Id; Lock_Name : Node_Id; Lock_Stmt : Node_Id; Service_Name : Node_Id; R : Node_Id; Return_Stmt : Node_Id := Empty; -- init to avoid gcc 3 warning Pre_Stmts : List_Id := No_List; -- init to avoid gcc 3 warning Stmts : List_Id; Object_Parm : Node_Id; Exc_Safe : Boolean; function Is_Exception_Safe (Subprogram : Node_Id) return Boolean; -- Tell whether a given subprogram cannot raise an exception ----------------------- -- Is_Exception_Safe -- ----------------------- function Is_Exception_Safe (Subprogram : Node_Id) return Boolean is function Has_Side_Effect (N : Node_Id) return Boolean; -- Return True whenever encountering a subprogram call or a -- raise statement of any kind in the sequence of statements N --------------------- -- Has_Side_Effect -- --------------------- -- What is this doing buried two levels down in exp_ch9. It -- seems like a generally useful function, and indeed there -- may be code duplication going on here ??? function Has_Side_Effect (N : Node_Id) return Boolean is Stmt : Node_Id := N; Expr : Node_Id; function Is_Call_Or_Raise (N : Node_Id) return Boolean; -- Indicate whether N is a subprogram call or a raise statement function Is_Call_Or_Raise (N : Node_Id) return Boolean is begin return Nkind (N) = N_Procedure_Call_Statement or else Nkind (N) = N_Function_Call or else Nkind (N) = N_Raise_Statement or else Nkind (N) = N_Raise_Constraint_Error or else Nkind (N) = N_Raise_Program_Error or else Nkind (N) = N_Raise_Storage_Error; end Is_Call_Or_Raise; -- Start of processing for Has_Side_Effect begin while Present (Stmt) loop if Is_Call_Or_Raise (Stmt) then return True; end if; -- An object declaration can also contain a function call -- or a raise statement if Nkind (Stmt) = N_Object_Declaration then Expr := Expression (Stmt); if Present (Expr) and then Is_Call_Or_Raise (Expr) then return True; end if; end if; Next (Stmt); end loop; return False; end Has_Side_Effect; -- Start of processing for Is_Exception_Safe begin -- If the checks handled by the back end are not disabled, we cannot -- ensure that no exception will be raised. if not Access_Checks_Suppressed (Empty) or else not Discriminant_Checks_Suppressed (Empty) or else not Range_Checks_Suppressed (Empty) or else not Index_Checks_Suppressed (Empty) or else Opt.Stack_Checking_Enabled then return False; end if; if Has_Side_Effect (First (Declarations (Subprogram))) or else Has_Side_Effect ( First (Statements (Handled_Statement_Sequence (Subprogram)))) then return False; else return True; end if; end Is_Exception_Safe; -- Start of processing for Build_Protected_Subprogram_Body begin Op_Spec := Specification (N); Exc_Safe := Is_Exception_Safe (N); P_Op_Spec := Build_Protected_Sub_Specification (N, Pid, Unprotected => False); -- Build a list of the formal parameters of the protected -- version of the subprogram to use as the actual parameters -- of the unprotected version. Uactuals := New_List; Pformal := First (Parameter_Specifications (P_Op_Spec)); while Present (Pformal) loop Append ( Make_Identifier (Loc, Chars (Defining_Identifier (Pformal))), Uactuals); Next (Pformal); end loop; -- Make a call to the unprotected version of the subprogram -- built above for use by the protected version built below. if Nkind (Op_Spec) = N_Function_Specification then if Exc_Safe then R := Make_Defining_Identifier (Loc, New_Internal_Name ('R')); Unprot_Call := Make_Object_Declaration (Loc, Defining_Identifier => R, Constant_Present => True, Object_Definition => New_Copy (Subtype_Mark (N_Op_Spec)), Expression => Make_Function_Call (Loc, Name => Make_Identifier (Loc, Chars (Defining_Unit_Name (N_Op_Spec))), Parameter_Associations => Uactuals)); Return_Stmt := Make_Return_Statement (Loc, Expression => New_Reference_To (R, Loc)); else Unprot_Call := Make_Return_Statement (Loc, Expression => Make_Function_Call (Loc, Name => Make_Identifier (Loc, Chars (Defining_Unit_Name (N_Op_Spec))), Parameter_Associations => Uactuals)); end if; else Unprot_Call := Make_Procedure_Call_Statement (Loc, Name => Make_Identifier (Loc, Chars (Defining_Unit_Name (N_Op_Spec))), Parameter_Associations => Uactuals); end if; -- Wrap call in block that will be covered by an at_end handler if not Exc_Safe then Unprot_Call := Make_Block_Statement (Loc, Handled_Statement_Sequence => Make_Handled_Sequence_Of_Statements (Loc, Statements => New_List (Unprot_Call))); end if; -- Make the protected subprogram body. This locks the protected -- object and calls the unprotected version of the subprogram. -- If the protected object is controlled (i.e it has entries or -- needs finalization for interrupt handling), call Lock_Entries, -- except if the protected object follows the Ravenscar profile, in -- which case call Lock_Entry, otherwise call the simplified version, -- Lock. if Has_Entries (Pid) or else Has_Interrupt_Handler (Pid) or else (Has_Attach_Handler (Pid) and then not Restricted_Profile) then if Abort_Allowed or else Restriction_Active (No_Entry_Queue) = False or else Number_Entries (Pid) > 1 then Lock_Name := New_Reference_To (RTE (RE_Lock_Entries), Loc); Service_Name := New_Reference_To (RTE (RE_Service_Entries), Loc); else Lock_Name := New_Reference_To (RTE (RE_Lock_Entry), Loc); Service_Name := New_Reference_To (RTE (RE_Service_Entry), Loc); end if; else Lock_Name := New_Reference_To (RTE (RE_Lock), Loc); Service_Name := New_Reference_To (RTE (RE_Unlock), Loc); end if; Object_Parm := Make_Attribute_Reference (Loc, Prefix => Make_Selected_Component (Loc, Prefix => Make_Identifier (Loc, Name_uObject), Selector_Name => Make_Identifier (Loc, Name_uObject)), Attribute_Name => Name_Unchecked_Access); Lock_Stmt := Make_Procedure_Call_Statement (Loc, Name => Lock_Name, Parameter_Associations => New_List (Object_Parm)); if Abort_Allowed then Stmts := New_List ( Make_Procedure_Call_Statement (Loc, Name => New_Reference_To (RTE (RE_Abort_Defer), Loc), Parameter_Associations => Empty_List), Lock_Stmt); else Stmts := New_List (Lock_Stmt); end if; if not Exc_Safe then Append (Unprot_Call, Stmts); else if Nkind (Op_Spec) = N_Function_Specification then Pre_Stmts := Stmts; Stmts := Empty_List; else Append (Unprot_Call, Stmts); end if; Append ( Make_Procedure_Call_Statement (Loc, Name => Service_Name, Parameter_Associations => New_List (New_Copy_Tree (Object_Parm))), Stmts); if Abort_Allowed then Append ( Make_Procedure_Call_Statement (Loc, Name => New_Reference_To (RTE (RE_Abort_Undefer), Loc), Parameter_Associations => Empty_List), Stmts); end if; if Nkind (Op_Spec) = N_Function_Specification then Append (Return_Stmt, Stmts); Append (Make_Block_Statement (Loc, Declarations => New_List (Unprot_Call), Handled_Statement_Sequence => Make_Handled_Sequence_Of_Statements (Loc, Statements => Stmts)), Pre_Stmts); Stmts := Pre_Stmts; end if; end if; Sub_Body := Make_Subprogram_Body (Loc, Declarations => Empty_List, Specification => P_Op_Spec, Handled_Statement_Sequence => Make_Handled_Sequence_Of_Statements (Loc, Statements => Stmts)); if not Exc_Safe then Set_Is_Protected_Subprogram_Body (Sub_Body); end if; return Sub_Body; end Build_Protected_Subprogram_Body; ------------------------------------- -- Build_Protected_Subprogram_Call -- ------------------------------------- procedure Build_Protected_Subprogram_Call (N : Node_Id; Name : Node_Id; Rec : Node_Id; External : Boolean := True) is Loc : constant Source_Ptr := Sloc (N); Sub : constant Entity_Id := Entity (Name); New_Sub : Node_Id; Params : List_Id; begin if External then New_Sub := New_Occurrence_Of (External_Subprogram (Sub), Loc); else New_Sub := New_Occurrence_Of (Protected_Body_Subprogram (Sub), Loc); end if; if Present (Parameter_Associations (N)) then Params := New_Copy_List_Tree (Parameter_Associations (N)); else Params := New_List; end if; Prepend (Rec, Params); if Ekind (Sub) = E_Procedure then Rewrite (N, Make_Procedure_Call_Statement (Loc, Name => New_Sub, Parameter_Associations => Params)); else pragma Assert (Ekind (Sub) = E_Function); Rewrite (N, Make_Function_Call (Loc, Name => New_Sub, Parameter_Associations => Params)); end if; if External and then Nkind (Rec) = N_Unchecked_Type_Conversion and then Is_Entity_Name (Expression (Rec)) and then Is_Shared_Passive (Entity (Expression (Rec))) then Add_Shared_Var_Lock_Procs (N); end if; end Build_Protected_Subprogram_Call; ------------------------- -- Build_Selected_Name -- ------------------------- function Build_Selected_Name (Prefix, Selector : Name_Id; Append_Char : Character := ' ') return Name_Id is Select_Buffer : String (1 .. Hostparm.Max_Name_Length); Select_Len : Natural; begin Get_Name_String (Selector); Select_Len := Name_Len; Select_Buffer (1 .. Select_Len) := Name_Buffer (1 .. Name_Len); Get_Name_String (Prefix); -- If scope is anonymous type, discard suffix to recover name of -- single protected object. Otherwise use protected type name. if Name_Buffer (Name_Len) = 'T' then Name_Len := Name_Len - 1; end if; Name_Buffer (Name_Len + 1) := '_'; Name_Buffer (Name_Len + 2) := '_'; Name_Len := Name_Len + 2; for J in 1 .. Select_Len loop Name_Len := Name_Len + 1; Name_Buffer (Name_Len) := Select_Buffer (J); end loop; if Append_Char /= ' ' then Name_Len := Name_Len + 1; Name_Buffer (Name_Len) := Append_Char; end if; return Name_Find; end Build_Selected_Name; ----------------------------- -- Build_Simple_Entry_Call -- ----------------------------- -- A task entry call is converted to a call to Call_Simple -- declare -- P : parms := (parm, parm, parm); -- begin -- Call_Simple (acceptor-task, entry-index, P'Address); -- parm := P.param; -- parm := P.param; -- ... -- end; -- Here Pnn is an aggregate of the type constructed for the entry to hold -- the parameters, and the constructed aggregate value contains either the -- parameters or, in the case of non-elementary types, references to these -- parameters. Then the address of this aggregate is passed to the runtime -- routine, along with the task id value and the task entry index value. -- Pnn is only required if parameters are present. -- The assignments after the call are present only in the case of in-out -- or out parameters for elementary types, and are used to assign back the -- resulting values of such parameters. -- Note: the reason that we insert a block here is that in the context -- of selects, conditional entry calls etc. the entry call statement -- appears on its own, not as an element of a list. -- A protected entry call is converted to a Protected_Entry_Call: -- declare -- P : E1_Params := (param, param, param); -- Pnn : Boolean; -- Bnn : Communications_Block; -- declare -- P : E1_Params := (param, param, param); -- Bnn : Communications_Block; -- begin -- Protected_Entry_Call ( -- Object => po._object'Access, -- E => ; -- Uninterpreted_Data => P'Address; -- Mode => Simple_Call; -- Block => Bnn); -- parm := P.param; -- parm := P.param; -- ... -- end; procedure Build_Simple_Entry_Call (N : Node_Id; Concval : Node_Id; Ename : Node_Id; Index : Node_Id) is begin Expand_Call (N); -- Convert entry call to Call_Simple call declare Loc : constant Source_Ptr := Sloc (N); Parms : constant List_Id := Parameter_Associations (N); Stats : constant List_Id := New_List; Pdecl : Node_Id; Xdecl : Node_Id; Decls : List_Id; Conctyp : Node_Id; Ent : Entity_Id; Ent_Acc : Entity_Id; P : Entity_Id; X : Entity_Id; Plist : List_Id; Parm1 : Node_Id; Parm2 : Node_Id; Parm3 : Node_Id; Call : Node_Id; Actual : Node_Id; Formal : Node_Id; N_Node : Node_Id; N_Var : Node_Id; Comm_Name : Entity_Id; begin -- Simple entry and entry family cases merge here Ent := Entity (Ename); Ent_Acc := Entry_Parameters_Type (Ent); Conctyp := Etype (Concval); -- If prefix is an access type, dereference to obtain the task type if Is_Access_Type (Conctyp) then Conctyp := Designated_Type (Conctyp); end if; -- Special case for protected subprogram calls if Is_Protected_Type (Conctyp) and then Is_Subprogram (Entity (Ename)) then if not Is_Eliminated (Entity (Ename)) then Build_Protected_Subprogram_Call (N, Ename, Convert_Concurrent (Concval, Conctyp)); Analyze (N); end if; return; end if; -- First parameter is the Task_Id value from the task value or the -- Object from the protected object value, obtained by selecting -- the _Task_Id or _Object from the result of doing an unchecked -- conversion to convert the value to the corresponding record type. Parm1 := Concurrent_Ref (Concval); -- Second parameter is the entry index, computed by the routine -- provided for this purpose. The value of this expression is -- assigned to an intermediate variable to assure that any entry -- family index expressions are evaluated before the entry -- parameters. if Abort_Allowed or else Restriction_Active (No_Entry_Queue) = False or else not Is_Protected_Type (Conctyp) or else Number_Entries (Conctyp) > 1 then X := Make_Defining_Identifier (Loc, Name_uX); Xdecl := Make_Object_Declaration (Loc, Defining_Identifier => X, Object_Definition => New_Reference_To (RTE (RE_Task_Entry_Index), Loc), Expression => Actual_Index_Expression ( Loc, Entity (Ename), Index, Concval)); Decls := New_List (Xdecl); Parm2 := New_Reference_To (X, Loc); else Xdecl := Empty; Decls := New_List; Parm2 := Empty; end if; -- The third parameter is the packaged parameters. If there are -- none, then it is just the null address, since nothing is passed if No (Parms) then Parm3 := New_Reference_To (RTE (RE_Null_Address), Loc); P := Empty; -- Case of parameters present, where third argument is the address -- of a packaged record containing the required parameter values. else -- First build a list of parameter values, which are -- references to objects of the parameter types. Plist := New_List; Actual := First_Actual (N); Formal := First_Formal (Ent); while Present (Actual) loop -- If it is a by_copy_type, copy it to a new variable. The -- packaged record has a field that points to this variable. if Is_By_Copy_Type (Etype (Actual)) then N_Node := Make_Object_Declaration (Loc, Defining_Identifier => Make_Defining_Identifier (Loc, Chars => New_Internal_Name ('J')), Aliased_Present => True, Object_Definition => New_Reference_To (Etype (Formal), Loc)); -- We have to make an assignment statement separate for -- the case of limited type. We can not assign it unless -- the Assignment_OK flag is set first. if Ekind (Formal) /= E_Out_Parameter then N_Var := New_Reference_To (Defining_Identifier (N_Node), Loc); Set_Assignment_OK (N_Var); Append_To (Stats, Make_Assignment_Statement (Loc, Name => N_Var, Expression => Relocate_Node (Actual))); end if; Append (N_Node, Decls); Append_To (Plist, Make_Attribute_Reference (Loc, Attribute_Name => Name_Unchecked_Access, Prefix => New_Reference_To (Defining_Identifier (N_Node), Loc))); else Append_To (Plist, Make_Reference (Loc, Prefix => Relocate_Node (Actual))); end if; Next_Actual (Actual); Next_Formal_With_Extras (Formal); end loop; -- Now build the declaration of parameters initialized with the -- aggregate containing this constructed parameter list. P := Make_Defining_Identifier (Loc, Name_uP); Pdecl := Make_Object_Declaration (Loc, Defining_Identifier => P, Object_Definition => New_Reference_To (Designated_Type (Ent_Acc), Loc), Expression => Make_Aggregate (Loc, Expressions => Plist)); Parm3 := Make_Attribute_Reference (Loc, Attribute_Name => Name_Address, Prefix => New_Reference_To (P, Loc)); Append (Pdecl, Decls); end if; -- Now we can create the call, case of protected type if Is_Protected_Type (Conctyp) then if Abort_Allowed or else Restriction_Active (No_Entry_Queue) = False or else Number_Entries (Conctyp) > 1 then -- Change the type of the index declaration Set_Object_Definition (Xdecl, New_Reference_To (RTE (RE_Protected_Entry_Index), Loc)); -- Some additional declarations for protected entry calls if No (Decls) then Decls := New_List; end if; -- Bnn : Communications_Block; Comm_Name := Make_Defining_Identifier (Loc, New_Internal_Name ('B')); Append_To (Decls, Make_Object_Declaration (Loc, Defining_Identifier => Comm_Name, Object_Definition => New_Reference_To (RTE (RE_Communication_Block), Loc))); -- Some additional statements for protected entry calls -- Protected_Entry_Call ( -- Object => po._object'Access, -- E => ; -- Uninterpreted_Data => P'Address; -- Mode => Simple_Call; -- Block => Bnn); Call := Make_Procedure_Call_Statement (Loc, Name => New_Reference_To (RTE (RE_Protected_Entry_Call), Loc), Parameter_Associations => New_List ( Make_Attribute_Reference (Loc, Attribute_Name => Name_Unchecked_Access, Prefix => Parm1), Parm2, Parm3, New_Reference_To (RTE (RE_Simple_Call), Loc), New_Occurrence_Of (Comm_Name, Loc))); else -- Protected_Single_Entry_Call ( -- Object => po._object'Access, -- Uninterpreted_Data => P'Address; -- Mode => Simple_Call); Call := Make_Procedure_Call_Statement (Loc, Name => New_Reference_To ( RTE (RE_Protected_Single_Entry_Call), Loc), Parameter_Associations => New_List ( Make_Attribute_Reference (Loc, Attribute_Name => Name_Unchecked_Access, Prefix => Parm1), Parm3, New_Reference_To (RTE (RE_Simple_Call), Loc))); end if; -- Case of task type else Call := Make_Procedure_Call_Statement (Loc, Name => New_Reference_To (RTE (RE_Call_Simple), Loc), Parameter_Associations => New_List (Parm1, Parm2, Parm3)); end if; Append_To (Stats, Call); -- If there are out or in/out parameters by copy -- add assignment statements for the result values. if Present (Parms) then Actual := First_Actual (N); Formal := First_Formal (Ent); Set_Assignment_OK (Actual); while Present (Actual) loop if Is_By_Copy_Type (Etype (Actual)) and then Ekind (Formal) /= E_In_Parameter then N_Node := Make_Assignment_Statement (Loc, Name => New_Copy (Actual), Expression => Make_Explicit_Dereference (Loc, Make_Selected_Component (Loc, Prefix => New_Reference_To (P, Loc), Selector_Name => Make_Identifier (Loc, Chars (Formal))))); -- In all cases (including limited private types) we -- want the assignment to be valid. Set_Assignment_OK (Name (N_Node)); -- If the call is the triggering alternative in an -- asynchronous select, or the entry_call alternative -- of a conditional entry call, the assignments for in-out -- parameters are incorporated into the statement list -- that follows, so that there are executed only if the -- entry call succeeds. if (Nkind (Parent (N)) = N_Triggering_Alternative and then N = Triggering_Statement (Parent (N))) or else (Nkind (Parent (N)) = N_Entry_Call_Alternative and then N = Entry_Call_Statement (Parent (N))) then if No (Statements (Parent (N))) then Set_Statements (Parent (N), New_List); end if; Prepend (N_Node, Statements (Parent (N))); else Insert_After (Call, N_Node); end if; end if; Next_Actual (Actual); Next_Formal_With_Extras (Formal); end loop; end if; -- Finally, create block and analyze it Rewrite (N, Make_Block_Statement (Loc, Declarations => Decls, Handled_Statement_Sequence => Make_Handled_Sequence_Of_Statements (Loc, Statements => Stats))); Analyze (N); end; end Build_Simple_Entry_Call; -------------------------------- -- Build_Task_Activation_Call -- -------------------------------- procedure Build_Task_Activation_Call (N : Node_Id) is Loc : constant Source_Ptr := Sloc (N); Chain : Entity_Id; Call : Node_Id; Name : Node_Id; P : Node_Id; begin -- Get the activation chain entity. Except in the case of a package -- body, this is in the node that w as passed. For a package body, we -- have to find the corresponding package declaration node. if Nkind (N) = N_Package_Body then P := Corresponding_Spec (N); loop P := Parent (P); exit when Nkind (P) = N_Package_Declaration; end loop; Chain := Activation_Chain_Entity (P); else Chain := Activation_Chain_Entity (N); end if; if Present (Chain) then if Restricted_Profile then Name := New_Reference_To (RTE (RE_Activate_Restricted_Tasks), Loc); else Name := New_Reference_To (RTE (RE_Activate_Tasks), Loc); end if; Call := Make_Procedure_Call_Statement (Loc, Name => Name, Parameter_Associations => New_List (Make_Attribute_Reference (Loc, Prefix => New_Occurrence_Of (Chain, Loc), Attribute_Name => Name_Unchecked_Access))); if Nkind (N) = N_Package_Declaration then if Present (Corresponding_Body (N)) then null; elsif Present (Private_Declarations (Specification (N))) then Append (Call, Private_Declarations (Specification (N))); else Append (Call, Visible_Declarations (Specification (N))); end if; else if Present (Handled_Statement_Sequence (N)) then -- The call goes at the start of the statement sequence, but -- after the start of exception range label if one is present. declare Stm : Node_Id; begin Stm := First (Statements (Handled_Statement_Sequence (N))); if Nkind (Stm) = N_Label and then Exception_Junk (Stm) then Next (Stm); end if; Insert_Before (Stm, Call); end; else Set_Handled_Statement_Sequence (N, Make_Handled_Sequence_Of_Statements (Loc, Statements => New_List (Call))); end if; end if; Analyze (Call); Check_Task_Activation (N); end if; end Build_Task_Activation_Call; ------------------------------- -- Build_Task_Allocate_Block -- ------------------------------- procedure Build_Task_Allocate_Block (Actions : List_Id; N : Node_Id; Args : List_Id) is T : constant Entity_Id := Entity (Expression (N)); Init : constant Entity_Id := Base_Init_Proc (T); Loc : constant Source_Ptr := Sloc (N); Chain : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uChain); Blkent : Entity_Id; Block : Node_Id; begin Blkent := Make_Defining_Identifier (Loc, New_Internal_Name ('A')); Block := Make_Block_Statement (Loc, Identifier => New_Reference_To (Blkent, Loc), Declarations => New_List ( -- _Chain : Activation_Chain; Make_Object_Declaration (Loc, Defining_Identifier => Chain, Aliased_Present => True, Object_Definition => New_Reference_To (RTE (RE_Activation_Chain), Loc))), Handled_Statement_Sequence => Make_Handled_Sequence_Of_Statements (Loc, Statements => New_List ( -- Init (Args); Make_Procedure_Call_Statement (Loc, Name => New_Reference_To (Init, Loc), Parameter_Associations => Args), -- Activate_Tasks (_Chain); Make_Procedure_Call_Statement (Loc, Name => New_Reference_To (RTE (RE_Activate_Tasks), Loc), Parameter_Associations => New_List ( Make_Attribute_Reference (Loc, Prefix => New_Reference_To (Chain, Loc), Attribute_Name => Name_Unchecked_Access))))), Has_Created_Identifier => True, Is_Task_Allocation_Block => True); Append_To (Actions, Make_Implicit_Label_Declaration (Loc, Defining_Identifier => Blkent, Label_Construct => Block)); Append_To (Actions, Block); Set_Activation_Chain_Entity (Block, Chain); end Build_Task_Allocate_Block; ----------------------------------------------- -- Build_Task_Allocate_Block_With_Init_Stmts -- ----------------------------------------------- procedure Build_Task_Allocate_Block_With_Init_Stmts (Actions : List_Id; N : Node_Id; Init_Stmts : List_Id) is Loc : constant Source_Ptr := Sloc (N); Chain : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uChain); Blkent : Entity_Id; Block : Node_Id; begin Blkent := Make_Defining_Identifier (Loc, New_Internal_Name ('A')); Append_To (Init_Stmts, Make_Procedure_Call_Statement (Loc, Name => New_Reference_To (RTE (RE_Activate_Tasks), Loc), Parameter_Associations => New_List ( Make_Attribute_Reference (Loc, Prefix => New_Reference_To (Chain, Loc), Attribute_Name => Name_Unchecked_Access)))); Block := Make_Block_Statement (Loc, Identifier => New_Reference_To (Blkent, Loc), Declarations => New_List ( -- _Chain : Activation_Chain; Make_Object_Declaration (Loc, Defining_Identifier => Chain, Aliased_Present => True, Object_Definition => New_Reference_To (RTE (RE_Activation_Chain), Loc))), Handled_Statement_Sequence => Make_Handled_Sequence_Of_Statements (Loc, Init_Stmts), Has_Created_Identifier => True, Is_Task_Allocation_Block => True); Append_To (Actions, Make_Implicit_Label_Declaration (Loc, Defining_Identifier => Blkent, Label_Construct => Block)); Append_To (Actions, Block); Set_Activation_Chain_Entity (Block, Chain); end Build_Task_Allocate_Block_With_Init_Stmts; ----------------------------------- -- Build_Task_Proc_Specification -- ----------------------------------- function Build_Task_Proc_Specification (T : Entity_Id) return Node_Id is Loc : constant Source_Ptr := Sloc (T); Nam : constant Name_Id := Chars (T); Tdec : constant Node_Id := Declaration_Node (T); Ent : Entity_Id; begin Ent := Make_Defining_Identifier (Loc, Chars => New_External_Name (Nam, 'B')); Set_Is_Internal (Ent); -- Associate the procedure with the task, if this is the declaration -- (and not the body) of the procedure. if No (Task_Body_Procedure (Tdec)) then Set_Task_Body_Procedure (Tdec, Ent); end if; return Make_Procedure_Specification (Loc, Defining_Unit_Name => Ent, Parameter_Specifications => New_List ( Make_Parameter_Specification (Loc, Defining_Identifier => Make_Defining_Identifier (Loc, Name_uTask), Parameter_Type => Make_Access_Definition (Loc, Subtype_Mark => New_Reference_To (Corresponding_Record_Type (T), Loc))))); end Build_Task_Proc_Specification; --------------------------------------- -- Build_Unprotected_Subprogram_Body -- --------------------------------------- function Build_Unprotected_Subprogram_Body (N : Node_Id; Pid : Node_Id) return Node_Id is Loc : constant Source_Ptr := Sloc (N); N_Op_Spec : Node_Id; Op_Decls : List_Id; begin -- Make an unprotected version of the subprogram for use -- within the same object, with a new name and an additional -- parameter representing the object. Op_Decls := Declarations (N); N_Op_Spec := Build_Protected_Sub_Specification (N, Pid, Unprotected => True); return Make_Subprogram_Body (Loc, Specification => N_Op_Spec, Declarations => Op_Decls, Handled_Statement_Sequence => Handled_Statement_Sequence (N)); end Build_Unprotected_Subprogram_Body; ---------------------------- -- Collect_Entry_Families -- ---------------------------- procedure Collect_Entry_Families (Loc : Source_Ptr; Cdecls : List_Id; Current_Node : in out Node_Id; Conctyp : Entity_Id) is Efam : Entity_Id; Efam_Decl : Node_Id; Efam_Type : Entity_Id; begin Efam := First_Entity (Conctyp); while Present (Efam) loop if Ekind (Efam) = E_Entry_Family then Efam_Type := Make_Defining_Identifier (Loc, Chars => New_Internal_Name ('F')); Efam_Decl := Make_Full_Type_Declaration (Loc, Defining_Identifier => Efam_Type, Type_Definition => Make_Unconstrained_Array_Definition (Loc, Subtype_Marks => (New_List ( New_Occurrence_Of ( Base_Type (Etype (Discrete_Subtype_Definition (Parent (Efam)))), Loc))), Component_Definition => Make_Component_Definition (Loc, Aliased_Present => False, Subtype_Indication => New_Reference_To (Standard_Character, Loc)))); Insert_After (Current_Node, Efam_Decl); Current_Node := Efam_Decl; Analyze (Efam_Decl); Append_To (Cdecls, Make_Component_Declaration (Loc, Defining_Identifier => Make_Defining_Identifier (Loc, Chars (Efam)), Component_Definition => Make_Component_Definition (Loc, Aliased_Present => False, Subtype_Indication => Make_Subtype_Indication (Loc, Subtype_Mark => New_Occurrence_Of (Efam_Type, Loc), Constraint => Make_Index_Or_Discriminant_Constraint (Loc, Constraints => New_List ( New_Occurrence_Of (Etype (Discrete_Subtype_Definition (Parent (Efam))), Loc))))))); end if; Next_Entity (Efam); end loop; end Collect_Entry_Families; -------------------- -- Concurrent_Ref -- -------------------- -- The expression returned for a reference to a concurrent -- object has the form: -- taskV!(name)._Task_Id -- for a task, and -- objectV!(name)._Object -- for a protected object. For the case of an access to a concurrent -- object, there is an extra explicit dereference: -- taskV!(name.all)._Task_Id -- objectV!(name.all)._Object -- here taskV and objectV are the types for the associated records, which -- contain the required _Task_Id and _Object fields for tasks and -- protected objects, respectively. -- For the case of a task type name, the expression is -- Self; -- i.e. a call to the Self function which returns precisely this Task_Id -- For the case of a protected type name, the expression is -- objectR -- which is a renaming of the _object field of the current object -- object record, passed into protected operations as a parameter. function Concurrent_Ref (N : Node_Id) return Node_Id is Loc : constant Source_Ptr := Sloc (N); Ntyp : constant Entity_Id := Etype (N); Dtyp : Entity_Id; Sel : Name_Id; function Is_Current_Task (T : Entity_Id) return Boolean; -- Check whether the reference is to the immediately enclosing task -- type, or to an outer one (rare but legal). --------------------- -- Is_Current_Task -- --------------------- function Is_Current_Task (T : Entity_Id) return Boolean is Scop : Entity_Id; begin Scop := Current_Scope; while Present (Scop) and then Scop /= Standard_Standard loop if Scop = T then return True; elsif Is_Task_Type (Scop) then return False; -- If this is a procedure nested within the task type, we must -- assume that it can be called from an inner task, and therefore -- cannot treat it as a local reference. elsif Is_Overloadable (Scop) and then In_Open_Scopes (T) then return False; else Scop := Scope (Scop); end if; end loop; -- We know that we are within the task body, so should have -- found it in scope. raise Program_Error; end Is_Current_Task; -- Start of processing for Concurrent_Ref begin if Is_Access_Type (Ntyp) then Dtyp := Designated_Type (Ntyp); if Is_Protected_Type (Dtyp) then Sel := Name_uObject; else Sel := Name_uTask_Id; end if; return Make_Selected_Component (Loc, Prefix => Unchecked_Convert_To (Corresponding_Record_Type (Dtyp), Make_Explicit_Dereference (Loc, N)), Selector_Name => Make_Identifier (Loc, Sel)); elsif Is_Entity_Name (N) and then Is_Concurrent_Type (Entity (N)) then if Is_Task_Type (Entity (N)) then if Is_Current_Task (Entity (N)) then return Make_Function_Call (Loc, Name => New_Reference_To (RTE (RE_Self), Loc)); else declare Decl : Node_Id; T_Self : constant Entity_Id := Make_Defining_Identifier (Loc, New_Internal_Name ('T')); T_Body : constant Node_Id := Parent (Corresponding_Body (Parent (Entity (N)))); begin Decl := Make_Object_Declaration (Loc, Defining_Identifier => T_Self, Object_Definition => New_Occurrence_Of (RTE (RO_ST_Task_Id), Loc), Expression => Make_Function_Call (Loc, Name => New_Reference_To (RTE (RE_Self), Loc))); Prepend (Decl, Declarations (T_Body)); Analyze (Decl); Set_Scope (T_Self, Entity (N)); return New_Occurrence_Of (T_Self, Loc); end; end if; else pragma Assert (Is_Protected_Type (Entity (N))); return New_Reference_To ( Object_Ref (Corresponding_Body (Parent (Base_Type (Ntyp)))), Loc); end if; else pragma Assert (Is_Concurrent_Type (Ntyp)); if Is_Protected_Type (Ntyp) then Sel := Name_uObject; else Sel := Name_uTask_Id; end if; return Make_Selected_Component (Loc, Prefix => Unchecked_Convert_To (Corresponding_Record_Type (Ntyp), New_Copy_Tree (N)), Selector_Name => Make_Identifier (Loc, Sel)); end if; end Concurrent_Ref; ------------------------ -- Convert_Concurrent -- ------------------------ function Convert_Concurrent (N : Node_Id; Typ : Entity_Id) return Node_Id is begin if not Is_Concurrent_Type (Typ) then return N; else return Unchecked_Convert_To (Corresponding_Record_Type (Typ), New_Copy_Tree (N)); end if; end Convert_Concurrent; ---------------------------- -- Entry_Index_Expression -- ---------------------------- function Entry_Index_Expression (Sloc : Source_Ptr; Ent : Entity_Id; Index : Node_Id; Ttyp : Entity_Id) return Node_Id is Expr : Node_Id; Num : Node_Id; Lo : Node_Id; Hi : Node_Id; Prev : Entity_Id; S : Node_Id; begin -- The queues of entries and entry families appear in textual -- order in the associated record. The entry index is computed as -- the sum of the number of queues for all entries that precede the -- designated one, to which is added the index expression, if this -- expression denotes a member of a family. -- The following is a place holder for the count of simple entries Num := Make_Integer_Literal (Sloc, 1); -- We construct an expression which is a series of addition -- operations. The first operand is the number of single entries that -- precede this one, the second operand is the index value relative -- to the start of the referenced family, and the remaining operands -- are the lengths of the entry families that precede this entry, i.e. -- the constructed expression is: -- number_simple_entries + -- (s'pos (index-value) - s'pos (family'first)) + 1 + -- family'length + ... -- where index-value is the given index value, and s is the index -- subtype (we have to use pos because the subtype might be an -- enumeration type preventing direct subtraction). -- Note that the task entry array is one-indexed. -- The upper bound of the entry family may be a discriminant, so we -- retrieve the lower bound explicitly to compute offset, rather than -- using the index subtype which may mention a discriminant. if Present (Index) then S := Etype (Discrete_Subtype_Definition (Declaration_Node (Ent))); Expr := Make_Op_Add (Sloc, Left_Opnd => Num, Right_Opnd => Family_Offset ( Sloc, Make_Attribute_Reference (Sloc, Attribute_Name => Name_Pos, Prefix => New_Reference_To (Base_Type (S), Sloc), Expressions => New_List (Relocate_Node (Index))), Type_Low_Bound (S), Ttyp)); else Expr := Num; end if; -- Now add lengths of preceding entries and entry families Prev := First_Entity (Ttyp); while Chars (Prev) /= Chars (Ent) or else (Ekind (Prev) /= Ekind (Ent)) or else not Sem_Ch6.Type_Conformant (Ent, Prev) loop if Ekind (Prev) = E_Entry then Set_Intval (Num, Intval (Num) + 1); elsif Ekind (Prev) = E_Entry_Family then S := Etype (Discrete_Subtype_Definition (Declaration_Node (Prev))); Lo := Type_Low_Bound (S); Hi := Type_High_Bound (S); Expr := Make_Op_Add (Sloc, Left_Opnd => Expr, Right_Opnd => Family_Size (Sloc, Hi, Lo, Ttyp)); -- Other components are anonymous types to be ignored else null; end if; Next_Entity (Prev); end loop; return Expr; end Entry_Index_Expression; --------------------------- -- Establish_Task_Master -- --------------------------- procedure Establish_Task_Master (N : Node_Id) is Call : Node_Id; begin if Restriction_Active (No_Task_Hierarchy) = False then Call := Build_Runtime_Call (Sloc (N), RE_Enter_Master); Prepend_To (Declarations (N), Call); Analyze (Call); end if; end Establish_Task_Master; -------------------------------- -- Expand_Accept_Declarations -- -------------------------------- -- Part of the expansion of an accept statement involves the creation of -- a declaration that can be referenced from the statement sequence of -- the accept: -- Ann : Address; -- This declaration is inserted immediately before the accept statement -- and it is important that it be inserted before the statements of the -- statement sequence are analyzed. Thus it would be too late to create -- this declaration in the Expand_N_Accept_Statement routine, which is -- why there is a separate procedure to be called directly from Sem_Ch9. -- Ann is used to hold the address of the record containing the parameters -- (see Expand_N_Entry_Call for more details on how this record is built). -- References to the parameters do an unchecked conversion of this address -- to a pointer to the required record type, and then access the field that -- holds the value of the required parameter. The entity for the address -- variable is held as the top stack element (i.e. the last element) of the -- Accept_Address stack in the corresponding entry entity, and this element -- must be set in place before the statements are processed. -- The above description applies to the case of a stand alone accept -- statement, i.e. one not appearing as part of a select alternative. -- For the case of an accept that appears as part of a select alternative -- of a selective accept, we must still create the declaration right away, -- since Ann is needed immediately, but there is an important difference: -- The declaration is inserted before the selective accept, not before -- the accept statement (which is not part of a list anyway, and so would -- not accommodate inserted declarations) -- We only need one address variable for the entire selective accept. So -- the Ann declaration is created only for the first accept alternative, -- and subsequent accept alternatives reference the same Ann variable. -- We can distinguish the two cases by seeing whether the accept statement -- is part of a list. If not, then it must be in an accept alternative. -- To expand the requeue statement, a label is provided at the end of -- the accept statement or alternative of which it is a part, so that -- the statement can be skipped after the requeue is complete. -- This label is created here rather than during the expansion of the -- accept statement, because it will be needed by any requeue -- statements within the accept, which are expanded before the -- accept. procedure Expand_Accept_Declarations (N : Node_Id; Ent : Entity_Id) is Loc : constant Source_Ptr := Sloc (N); Ann : Entity_Id := Empty; Adecl : Node_Id; Lab_Id : Node_Id; Lab : Node_Id; Ldecl : Node_Id; Ldecl2 : Node_Id; begin if Expander_Active then -- If we have no handled statement sequence, then build a dummy -- sequence consisting of a null statement. This is only done if -- pragma FIFO_Within_Priorities is specified. The issue here is -- that even a null accept body has an effect on the called task -- in terms of its position in the queue, so we cannot optimize -- the context switch away. However, if FIFO_Within_Priorities -- is not active, the optimization is legitimate, since we can -- say that our dispatching policy (i.e. the default dispatching -- policy) reorders the queue to be the same as just before the -- call. In the absence of a specified dispatching policy, we are -- allowed to modify queue orders for a given priority at will! if Opt.Task_Dispatching_Policy = 'F' and then not Present (Handled_Statement_Sequence (N)) then Set_Handled_Statement_Sequence (N, Make_Handled_Sequence_Of_Statements (Loc, New_List (Make_Null_Statement (Loc)))); end if; -- Create and declare two labels to be placed at the end of the -- accept statement. The first label is used to allow requeues to -- skip the remainder of entry processing. The second label is -- used to skip the remainder of entry processing if the rendezvous -- completes in the middle of the accept body. if Present (Handled_Statement_Sequence (N)) then Lab_Id := Make_Identifier (Loc, New_Internal_Name ('L')); Set_Entity (Lab_Id, Make_Defining_Identifier (Loc, Chars (Lab_Id))); Lab := Make_Label (Loc, Lab_Id); Ldecl := Make_Implicit_Label_Declaration (Loc, Defining_Identifier => Entity (Lab_Id), Label_Construct => Lab); Append (Lab, Statements (Handled_Statement_Sequence (N))); Lab_Id := Make_Identifier (Loc, New_Internal_Name ('L')); Set_Entity (Lab_Id, Make_Defining_Identifier (Loc, Chars (Lab_Id))); Lab := Make_Label (Loc, Lab_Id); Ldecl2 := Make_Implicit_Label_Declaration (Loc, Defining_Identifier => Entity (Lab_Id), Label_Construct => Lab); Append (Lab, Statements (Handled_Statement_Sequence (N))); else Ldecl := Empty; Ldecl2 := Empty; end if; -- Case of stand alone accept statement if Is_List_Member (N) then if Present (Handled_Statement_Sequence (N)) then Ann := Make_Defining_Identifier (Loc, Chars => New_Internal_Name ('A')); Adecl := Make_Object_Declaration (Loc, Defining_Identifier => Ann, Object_Definition => New_Reference_To (RTE (RE_Address), Loc)); Insert_Before (N, Adecl); Analyze (Adecl); Insert_Before (N, Ldecl); Analyze (Ldecl); Insert_Before (N, Ldecl2); Analyze (Ldecl2); end if; -- Case of accept statement which is in an accept alternative else declare Acc_Alt : constant Node_Id := Parent (N); Sel_Acc : constant Node_Id := Parent (Acc_Alt); Alt : Node_Id; begin pragma Assert (Nkind (Acc_Alt) = N_Accept_Alternative); pragma Assert (Nkind (Sel_Acc) = N_Selective_Accept); -- ??? Consider a single label for select statements if Present (Handled_Statement_Sequence (N)) then Prepend (Ldecl2, Statements (Handled_Statement_Sequence (N))); Analyze (Ldecl2); Prepend (Ldecl, Statements (Handled_Statement_Sequence (N))); Analyze (Ldecl); end if; -- Find first accept alternative of the selective accept. A -- valid selective accept must have at least one accept in it. Alt := First (Select_Alternatives (Sel_Acc)); while Nkind (Alt) /= N_Accept_Alternative loop Next (Alt); end loop; -- If we are the first accept statement, then we have to -- create the Ann variable, as for the stand alone case, -- except that it is inserted before the selective accept. -- Similarly, a label for requeue expansion must be -- declared. if N = Accept_Statement (Alt) then Ann := Make_Defining_Identifier (Loc, New_Internal_Name ('A')); Adecl := Make_Object_Declaration (Loc, Defining_Identifier => Ann, Object_Definition => New_Reference_To (RTE (RE_Address), Loc)); Insert_Before (Sel_Acc, Adecl); Analyze (Adecl); -- If we are not the first accept statement, then find the -- Ann variable allocated by the first accept and use it. else Ann := Node (Last_Elmt (Accept_Address (Entity (Entry_Direct_Name (Accept_Statement (Alt)))))); end if; end; end if; -- Merge here with Ann either created or referenced, and Adecl -- pointing to the corresponding declaration. Remaining processing -- is the same for the two cases. if Present (Ann) then Append_Elmt (Ann, Accept_Address (Ent)); Set_Needs_Debug_Info (Ann); end if; -- Create renaming declarations for the entry formals. Each -- reference to a formal becomes a dereference of a component -- of the parameter block, whose address is held in Ann. -- These declarations are eventually inserted into the accept -- block, and analyzed there so that they have the proper scope -- for gdb and do not conflict with other declarations. if Present (Parameter_Specifications (N)) and then Present (Handled_Statement_Sequence (N)) then declare Formal : Entity_Id; New_F : Entity_Id; Comp : Entity_Id; Decl : Node_Id; begin New_Scope (Ent); Formal := First_Formal (Ent); while Present (Formal) loop Comp := Entry_Component (Formal); New_F := Make_Defining_Identifier (Sloc (Formal), Chars (Formal)); Set_Etype (New_F, Etype (Formal)); Set_Scope (New_F, Ent); Set_Needs_Debug_Info (New_F); -- That's the whole point. if Ekind (Formal) = E_In_Parameter then Set_Ekind (New_F, E_Constant); else Set_Ekind (New_F, E_Variable); Set_Extra_Constrained (New_F, Extra_Constrained (Formal)); end if; Set_Actual_Subtype (New_F, Actual_Subtype (Formal)); Decl := Make_Object_Renaming_Declaration (Loc, Defining_Identifier => New_F, Subtype_Mark => New_Reference_To (Etype (Formal), Loc), Name => Make_Explicit_Dereference (Loc, Make_Selected_Component (Loc, Prefix => Unchecked_Convert_To (Entry_Parameters_Type (Ent), New_Reference_To (Ann, Loc)), Selector_Name => New_Reference_To (Comp, Loc)))); if No (Declarations (N)) then Set_Declarations (N, New_List); end if; Append (Decl, Declarations (N)); Set_Renamed_Object (Formal, New_F); Next_Formal (Formal); end loop; End_Scope; end; end if; end if; end Expand_Accept_Declarations; --------------------------------------------- -- Expand_Access_Protected_Subprogram_Type -- --------------------------------------------- procedure Expand_Access_Protected_Subprogram_Type (N : Node_Id) is Loc : constant Source_Ptr := Sloc (N); Comps : List_Id; T : constant Entity_Id := Defining_Identifier (N); D_T : constant Entity_Id := Designated_Type (T); D_T2 : constant Entity_Id := Make_Defining_Identifier (Loc, New_Internal_Name ('D')); E_T : constant Entity_Id := Make_Defining_Identifier (Loc, New_Internal_Name ('E')); P_List : constant List_Id := Build_Protected_Spec (N, RTE (RE_Address), False, D_T); Decl1 : Node_Id; Decl2 : Node_Id; Def1 : Node_Id; begin -- Create access to protected subprogram with full signature if Nkind (Type_Definition (N)) = N_Access_Function_Definition then Def1 := Make_Access_Function_Definition (Loc, Parameter_Specifications => P_List, Subtype_Mark => New_Copy (Subtype_Mark (Type_Definition (N)))); else Def1 := Make_Access_Procedure_Definition (Loc, Parameter_Specifications => P_List); end if; Decl1 := Make_Full_Type_Declaration (Loc, Defining_Identifier => D_T2, Type_Definition => Def1); Analyze (Decl1); Insert_After (N, Decl1); -- Create Equivalent_Type, a record with two components for an -- access to object and an access to subprogram. Comps := New_List ( Make_Component_Declaration (Loc, Defining_Identifier => Make_Defining_Identifier (Loc, New_Internal_Name ('P')), Component_Definition => Make_Component_Definition (Loc, Aliased_Present => False, Subtype_Indication => New_Occurrence_Of (RTE (RE_Address), Loc))), Make_Component_Declaration (Loc, Defining_Identifier => Make_Defining_Identifier (Loc, New_Internal_Name ('S')), Component_Definition => Make_Component_Definition (Loc, Aliased_Present => False, Subtype_Indication => New_Occurrence_Of (D_T2, Loc)))); Decl2 := Make_Full_Type_Declaration (Loc, Defining_Identifier => E_T, Type_Definition => Make_Record_Definition (Loc, Component_List => Make_Component_List (Loc, Component_Items => Comps))); Analyze (Decl2); Insert_After (Decl1, Decl2); Set_Equivalent_Type (T, E_T); end Expand_Access_Protected_Subprogram_Type; -------------------------- -- Expand_Entry_Barrier -- -------------------------- procedure Expand_Entry_Barrier (N : Node_Id; Ent : Entity_Id) is Loc : constant Source_Ptr := Sloc (N); Prot : constant Entity_Id := Scope (Ent); Spec_Decl : constant Node_Id := Parent (Prot); Cond : constant Node_Id := Condition (Entry_Body_Formal_Part (N)); Func : Node_Id; B_F : Node_Id; Body_Decl : Node_Id; begin if No_Run_Time_Mode then Error_Msg_CRT ("entry barrier", N); return; end if; -- The body of the entry barrier must be analyzed in the context of -- the protected object, but its scope is external to it, just as any -- other unprotected version of a protected operation. The specification -- has been produced when the protected type declaration was elaborated. -- We build the body, insert it in the enclosing scope, but analyze it -- in the current context. A more uniform approach would be to treat a -- barrier just as a protected function, and discard the protected -- version of it because it is never called. if Expander_Active then B_F := Build_Barrier_Function (N, Ent, Prot); Func := Barrier_Function (Ent); Set_Corresponding_Spec (B_F, Func); Body_Decl := Parent (Corresponding_Body (Spec_Decl)); if Nkind (Parent (Body_Decl)) = N_Subunit then Body_Decl := Corresponding_Stub (Parent (Body_Decl)); end if; Insert_Before_And_Analyze (Body_Decl, B_F); Update_Prival_Subtypes (B_F); Set_Privals (Spec_Decl, N, Loc); Set_Discriminals (Spec_Decl); Set_Scope (Func, Scope (Prot)); else Analyze_And_Resolve (Cond, Any_Boolean); end if; -- The Ravenscar profile restricts barriers to simple variables -- declared within the protected object. We also allow Boolean -- constants, since these appear in several published examples -- and are also allowed by the Aonix compiler. -- Note that after analysis variables in this context will be -- replaced by the corresponding prival, that is to say a renaming -- of a selected component of the form _Object.Var. If expansion is -- disabled, as within a generic, we check that the entity appears in -- the current scope. if Is_Entity_Name (Cond) then if Entity (Cond) = Standard_False or else Entity (Cond) = Standard_True then return; elsif not Expander_Active and then Scope (Entity (Cond)) = Current_Scope then return; -- Check for case of _object.all.field (note that the explicit -- dereference gets inserted by analyze/expand of _object.field) elsif Present (Renamed_Object (Entity (Cond))) and then Nkind (Renamed_Object (Entity (Cond))) = N_Selected_Component and then Chars (Prefix (Prefix (Renamed_Object (Entity (Cond))))) = Name_uObject then return; end if; end if; -- It is not a boolean variable or literal, so check the restriction Check_Restriction (Simple_Barriers, Cond); end Expand_Entry_Barrier; ------------------------------------ -- Expand_Entry_Body_Declarations -- ------------------------------------ procedure Expand_Entry_Body_Declarations (N : Node_Id) is Loc : constant Source_Ptr := Sloc (N); Index_Spec : Node_Id; begin if Expander_Active then -- Expand entry bodies corresponding to entry families -- by assigning a placeholder for the constant that will -- be used to expand references to the entry index parameter. Index_Spec := Entry_Index_Specification (Entry_Body_Formal_Part (N)); if Present (Index_Spec) then Set_Entry_Index_Constant ( Defining_Identifier (Index_Spec), Make_Defining_Identifier (Loc, New_Internal_Name ('J'))); end if; end if; end Expand_Entry_Body_Declarations; ------------------------------ -- Expand_N_Abort_Statement -- ------------------------------ -- Expand abort T1, T2, .. Tn; into: -- Abort_Tasks (Task_List'(1 => T1.Task_Id, 2 => T2.Task_Id ...)) procedure Expand_N_Abort_Statement (N : Node_Id) is Loc : constant Source_Ptr := Sloc (N); Tlist : constant List_Id := Names (N); Count : Nat; Aggr : Node_Id; Tasknm : Node_Id; begin Aggr := Make_Aggregate (Loc, Component_Associations => New_List); Count := 0; Tasknm := First (Tlist); while Present (Tasknm) loop Count := Count + 1; Append_To (Component_Associations (Aggr), Make_Component_Association (Loc, Choices => New_List ( Make_Integer_Literal (Loc, Count)), Expression => Concurrent_Ref (Tasknm))); Next (Tasknm); end loop; Rewrite (N, Make_Procedure_Call_Statement (Loc, Name => New_Reference_To (RTE (RE_Abort_Tasks), Loc), Parameter_Associations => New_List ( Make_Qualified_Expression (Loc, Subtype_Mark => New_Reference_To (RTE (RE_Task_List), Loc), Expression => Aggr)))); Analyze (N); end Expand_N_Abort_Statement; ------------------------------- -- Expand_N_Accept_Statement -- ------------------------------- -- This procedure handles expansion of accept statements that stand -- alone, i.e. they are not part of an accept alternative. The expansion -- of accept statement in accept alternatives is handled by the routines -- Expand_N_Accept_Alternative and Expand_N_Selective_Accept. The -- following description applies only to stand alone accept statements. -- If there is no handled statement sequence, or only null statements, -- then this is called a trivial accept, and the expansion is: -- Accept_Trivial (entry-index) -- If there is a handled statement sequence, then the expansion is: -- Ann : Address; -- {Lnn : Label} -- begin -- begin -- Accept_Call (entry-index, Ann); -- Renaming_Declarations for formals -- -- Complete_Rendezvous; -- <> -- -- exception -- when ... => -- -- Complete_Rendezvous; -- when ... => -- -- Complete_Rendezvous; -- ... -- end; -- exception -- when all others => -- Exceptional_Complete_Rendezvous (Get_GNAT_Exception); -- end; -- The first three declarations were already inserted ahead of the -- accept statement by the Expand_Accept_Declarations procedure, which -- was called directly from the semantics during analysis of the accept. -- statement, before analyzing its contained statements. -- The declarations from the N_Accept_Statement, as noted in Sinfo, come -- from possible expansion activity (the original source of course does -- not have any declarations associated with the accept statement, since -- an accept statement has no declarative part). In particular, if the -- expander is active, the first such declaration is the declaration of -- the Accept_Params_Ptr entity (see Sem_Ch9.Analyze_Accept_Statement). -- -- The two blocks are merged into a single block if the inner block has -- no exception handlers, but otherwise two blocks are required, since -- exceptions might be raised in the exception handlers of the inner -- block, and Exceptional_Complete_Rendezvous must be called. procedure Expand_N_Accept_Statement (N : Node_Id) is Loc : constant Source_Ptr := Sloc (N); Stats : constant Node_Id := Handled_Statement_Sequence (N); Ename : constant Node_Id := Entry_Direct_Name (N); Eindx : constant Node_Id := Entry_Index (N); Eent : constant Entity_Id := Entity (Ename); Acstack : constant Elist_Id := Accept_Address (Eent); Ann : constant Entity_Id := Node (Last_Elmt (Acstack)); Ttyp : constant Entity_Id := Etype (Scope (Eent)); Blkent : Entity_Id; Call : Node_Id; Block : Node_Id; function Null_Statements (Stats : List_Id) return Boolean; -- Check for null statement sequence (i.e a list of labels and -- null statements) function Null_Statements (Stats : List_Id) return Boolean is Stmt : Node_Id; begin Stmt := First (Stats); while Nkind (Stmt) /= N_Empty and then (Nkind (Stmt) = N_Null_Statement or else Nkind (Stmt) = N_Label) loop Next (Stmt); end loop; return Nkind (Stmt) = N_Empty; end Null_Statements; -- Start of processing for Expand_N_Accept_Statement begin -- If accept statement is not part of a list, then its parent must be -- an accept alternative, and, as described above, we do not do any -- expansion for such accept statements at this level. if not Is_List_Member (N) then pragma Assert (Nkind (Parent (N)) = N_Accept_Alternative); return; -- Trivial accept case (no statement sequence, or null statements). -- If the accept statement has declarations, then just insert them -- before the procedure call. -- We avoid this optimization when FIFO_Within_Priorities is active, -- since it is not correct according to annex D semantics. The problem -- is that the call is required to reorder the acceptors position on -- its ready queue, even though there is nothing to be done. However, -- if no policy is specified, then we decide that our dispatching -- policy always reorders the queue right after the RV to look the -- way they were just before the RV. Since we are allowed to freely -- reorder same-priority queues (this is part of what dispatching -- policies are all about), the optimization is legitimate. elsif Opt.Task_Dispatching_Policy /= 'F' and then (No (Stats) or else Null_Statements (Statements (Stats))) then -- Remove declarations for renamings, because the parameter block -- will not be assigned. declare D : Node_Id; Next_D : Node_Id; begin D := First (Declarations (N)); while Present (D) loop Next_D := Next (D); if Nkind (D) = N_Object_Renaming_Declaration then Remove (D); end if; D := Next_D; end loop; end; if Present (Declarations (N)) then Insert_Actions (N, Declarations (N)); end if; Rewrite (N, Make_Procedure_Call_Statement (Loc, Name => New_Reference_To (RTE (RE_Accept_Trivial), Loc), Parameter_Associations => New_List ( Entry_Index_Expression (Loc, Entity (Ename), Eindx, Ttyp)))); Analyze (N); -- Discard Entry_Address that was created for it, so it will not be -- emitted if this accept statement is in the statement part of a -- delay alternative. if Present (Stats) then Remove_Last_Elmt (Acstack); end if; -- Case of statement sequence present else -- Construct the block, using the declarations from the accept -- statement if any to initialize the declarations of the block. Blkent := Make_Defining_Identifier (Loc, New_Internal_Name ('A')); Set_Ekind (Blkent, E_Block); Set_Etype (Blkent, Standard_Void_Type); Set_Scope (Blkent, Current_Scope); Block := Make_Block_Statement (Loc, Identifier => New_Reference_To (Blkent, Loc), Declarations => Declarations (N), Handled_Statement_Sequence => Build_Accept_Body (N)); -- Prepend call to Accept_Call to main statement sequence -- If the accept has exception handlers, the statement sequence -- is wrapped in a block. Insert call and renaming declarations -- in the declarations of the block, so they are elaborated before -- the handlers. Call := Make_Procedure_Call_Statement (Loc, Name => New_Reference_To (RTE (RE_Accept_Call), Loc), Parameter_Associations => New_List ( Entry_Index_Expression (Loc, Entity (Ename), Eindx, Ttyp), New_Reference_To (Ann, Loc))); if Parent (Stats) = N then Prepend (Call, Statements (Stats)); else Set_Declarations (Parent (Stats), New_List (Call)); end if; Analyze (Call); New_Scope (Blkent); declare D : Node_Id; Next_D : Node_Id; Typ : Entity_Id; begin D := First (Declarations (N)); while Present (D) loop Next_D := Next (D); if Nkind (D) = N_Object_Renaming_Declaration then -- The renaming declarations for the formals were -- created during analysis of the accept statement, -- and attached to the list of declarations. Place -- them now in the context of the accept block or -- subprogram. Remove (D); Typ := Entity (Subtype_Mark (D)); Insert_After (Call, D); Analyze (D); -- If the formal is class_wide, it does not have an -- actual subtype. The analysis of the renaming declaration -- creates one, but we need to retain the class-wide -- nature of the entity. if Is_Class_Wide_Type (Typ) then Set_Etype (Defining_Identifier (D), Typ); end if; end if; D := Next_D; end loop; end; End_Scope; -- Replace the accept statement by the new block Rewrite (N, Block); Analyze (N); -- Last step is to unstack the Accept_Address value Remove_Last_Elmt (Acstack); end if; end Expand_N_Accept_Statement; ---------------------------------- -- Expand_N_Asynchronous_Select -- ---------------------------------- -- This procedure assumes that the trigger statement is an entry call. A -- delay alternative should already have been expanded into an entry call -- to the appropriate delay object Wait entry. -- If the trigger is a task entry call, the select is implemented with -- a Task_Entry_Call: -- declare -- B : Boolean; -- C : Boolean; -- P : parms := (parm, parm, parm); -- -- Clean is added by Exp_Ch7.Expand_Cleanup_Actions -- procedure _clean is -- begin -- ... -- Cancel_Task_Entry_Call (C); -- ... -- end _clean; -- begin -- Abort_Defer; -- Task_Entry_Call -- (acceptor-task, -- entry-index, -- P'Address, -- Asynchronous_Call, -- B); -- begin -- begin -- Abort_Undefer; -- abortable-part -- at end -- _clean; -- Added by Exp_Ch7.Expand_Cleanup_Actions. -- end; -- exception -- when Abort_Signal => Abort_Undefer; -- end; -- parm := P.param; -- parm := P.param; -- ... -- if not C then -- triggered-statements -- end if; -- end; -- Note that Build_Simple_Entry_Call is used to expand the entry -- of the asynchronous entry call (by the -- Expand_N_Entry_Call_Statement procedure) as follows: -- declare -- P : parms := (parm, parm, parm); -- begin -- Call_Simple (acceptor-task, entry-index, P'Address); -- parm := P.param; -- parm := P.param; -- ... -- end; -- so the task at hand is to convert the latter expansion into the former -- If the trigger is a protected entry call, the select is -- implemented with Protected_Entry_Call: -- declare -- P : E1_Params := (param, param, param); -- Bnn : Communications_Block; -- begin -- declare -- -- Clean is added by Exp_Ch7.Expand_Cleanup_Actions. -- procedure _clean is -- begin -- ... -- if Enqueued (Bnn) then -- Cancel_Protected_Entry_Call (Bnn); -- end if; -- ... -- end _clean; -- begin -- begin -- Protected_Entry_Call ( -- Object => po._object'Access, -- E => ; -- Uninterpreted_Data => P'Address; -- Mode => Asynchronous_Call; -- Block => Bnn); -- if Enqueued (Bnn) then -- -- end if; -- at end -- _clean; -- Added by Exp_Ch7.Expand_Cleanup_Actions. -- end; -- exception -- when Abort_Signal => -- Abort_Undefer; -- null; -- end; -- if not Cancelled (Bnn) then -- triggered statements -- end if; -- end; -- Build_Simple_Entry_Call is used to expand the all to a simple -- protected entry call: -- declare -- P : E1_Params := (param, param, param); -- Bnn : Communications_Block; -- begin -- Protected_Entry_Call ( -- Object => po._object'Access, -- E => ; -- Uninterpreted_Data => P'Address; -- Mode => Simple_Call; -- Block => Bnn); -- parm := P.param; -- parm := P.param; -- ... -- end; -- The job is to convert this to the asynchronous form -- If the trigger is a delay statement, it will have been expanded into a -- call to one of the GNARL delay procedures. This routine will convert -- this into a protected entry call on a delay object and then continue -- processing as for a protected entry call trigger. This requires -- declaring a Delay_Block object and adding a pointer to this object to -- the parameter list of the delay procedure to form the parameter list of -- the entry call. This object is used by the runtime to queue the delay -- request. -- For a description of the use of P and the assignments after the -- call, see Expand_N_Entry_Call_Statement. procedure Expand_N_Asynchronous_Select (N : Node_Id) is Loc : constant Source_Ptr := Sloc (N); Trig : constant Node_Id := Triggering_Alternative (N); Abrt : constant Node_Id := Abortable_Part (N); Tstats : constant List_Id := Statements (Trig); Astats : constant List_Id := Statements (Abrt); Ecall : Node_Id; Concval : Node_Id; Ename : Node_Id; Index : Node_Id; Hdle : List_Id; Decls : List_Id; Decl : Node_Id; Parms : List_Id; Parm : Node_Id; Call : Node_Id; Stmts : List_Id; Enqueue_Call : Node_Id; Stmt : Node_Id; B : Entity_Id; Pdef : Entity_Id; Dblock_Ent : Entity_Id; N_Orig : Node_Id; Abortable_Block : Node_Id; Cancel_Param : Entity_Id; Blkent : Entity_Id; Target_Undefer : RE_Id; Undefer_Args : List_Id := No_List; begin Blkent := Make_Defining_Identifier (Loc, New_Internal_Name ('A')); Ecall := Triggering_Statement (Trig); -- The arguments in the call may require dynamic allocation, and the -- call statement may have been transformed into a block. The block -- may contain additional declarations for internal entities, and the -- original call is found by sequential search. if Nkind (Ecall) = N_Block_Statement then Ecall := First (Statements (Handled_Statement_Sequence (Ecall))); while Nkind (Ecall) /= N_Procedure_Call_Statement and then Nkind (Ecall) /= N_Entry_Call_Statement loop Next (Ecall); end loop; end if; -- If a delay was used as a trigger, it will have been expanded -- into a procedure call. Convert it to the appropriate sequence of -- statements, similar to what is done for a task entry call. -- Note that this currently supports only Duration, Real_Time.Time, -- and Calendar.Time. if Nkind (Ecall) = N_Procedure_Call_Statement then -- Add a Delay_Block object to the parameter list of the -- delay procedure to form the parameter list of the Wait -- entry call. Dblock_Ent := Make_Defining_Identifier (Loc, New_Internal_Name ('D')); Pdef := Entity (Name (Ecall)); if Is_RTE (Pdef, RO_CA_Delay_For) then Enqueue_Call := New_Reference_To (RTE (RE_Enqueue_Duration), Loc); elsif Is_RTE (Pdef, RO_CA_Delay_Until) then Enqueue_Call := New_Reference_To (RTE (RE_Enqueue_Calendar), Loc); else pragma Assert (Is_RTE (Pdef, RO_RT_Delay_Until)); Enqueue_Call := New_Reference_To (RTE (RE_Enqueue_RT), Loc); end if; Append_To (Parameter_Associations (Ecall), Make_Attribute_Reference (Loc, Prefix => New_Reference_To (Dblock_Ent, Loc), Attribute_Name => Name_Unchecked_Access)); -- Create the inner block to protect the abortable part Hdle := New_List ( Make_Exception_Handler (Loc, Exception_Choices => New_List (New_Reference_To (Stand.Abort_Signal, Loc)), Statements => New_List ( Make_Procedure_Call_Statement (Loc, Name => New_Reference_To (RTE (RE_Abort_Undefer), Loc))))); Prepend_To (Astats, Make_Procedure_Call_Statement (Loc, Name => New_Reference_To (RTE (RE_Abort_Undefer), Loc))); Abortable_Block := Make_Block_Statement (Loc, Identifier => New_Reference_To (Blkent, Loc), Handled_Statement_Sequence => Make_Handled_Sequence_Of_Statements (Loc, Statements => Astats), Has_Created_Identifier => True, Is_Asynchronous_Call_Block => True); -- Append call to if Enqueue (When, DB'Unchecked_Access) then Rewrite (Ecall, Make_Implicit_If_Statement (N, Condition => Make_Function_Call (Loc, Name => Enqueue_Call, Parameter_Associations => Parameter_Associations (Ecall)), Then_Statements => New_List (Make_Block_Statement (Loc, Handled_Statement_Sequence => Make_Handled_Sequence_Of_Statements (Loc, Statements => New_List ( Make_Implicit_Label_Declaration (Loc, Defining_Identifier => Blkent, Label_Construct => Abortable_Block), Abortable_Block), Exception_Handlers => Hdle))))); Stmts := New_List (Ecall); -- Construct statement sequence for new block Append_To (Stmts, Make_Implicit_If_Statement (N, Condition => Make_Function_Call (Loc, Name => New_Reference_To ( RTE (RE_Timed_Out), Loc), Parameter_Associations => New_List ( Make_Attribute_Reference (Loc, Prefix => New_Reference_To (Dblock_Ent, Loc), Attribute_Name => Name_Unchecked_Access))), Then_Statements => Tstats)); -- The result is the new block Set_Entry_Cancel_Parameter (Blkent, Dblock_Ent); Rewrite (N, Make_Block_Statement (Loc, Declarations => New_List ( Make_Object_Declaration (Loc, Defining_Identifier => Dblock_Ent, Aliased_Present => True, Object_Definition => New_Reference_To ( RTE (RE_Delay_Block), Loc))), Handled_Statement_Sequence => Make_Handled_Sequence_Of_Statements (Loc, Stmts))); Analyze (N); return; else N_Orig := N; end if; Extract_Entry (Ecall, Concval, Ename, Index); Build_Simple_Entry_Call (Ecall, Concval, Ename, Index); Stmts := Statements (Handled_Statement_Sequence (Ecall)); Decls := Declarations (Ecall); if Is_Protected_Type (Etype (Concval)) then -- Get the declarations of the block expanded from the entry call Decl := First (Decls); while Present (Decl) and then (Nkind (Decl) /= N_Object_Declaration or else not Is_RTE (Etype (Object_Definition (Decl)), RE_Communication_Block)) loop Next (Decl); end loop; pragma Assert (Present (Decl)); Cancel_Param := Defining_Identifier (Decl); -- Change the mode of the Protected_Entry_Call call. -- Protected_Entry_Call ( -- Object => po._object'Access, -- E => ; -- Uninterpreted_Data => P'Address; -- Mode => Asynchronous_Call; -- Block => Bnn); Stmt := First (Stmts); -- Skip assignments to temporaries created for in-out parameters. -- This makes unwarranted assumptions about the shape of the expanded -- tree for the call, and should be cleaned up ??? while Nkind (Stmt) /= N_Procedure_Call_Statement loop Next (Stmt); end loop; Call := Stmt; Parm := First (Parameter_Associations (Call)); while Present (Parm) and then not Is_RTE (Etype (Parm), RE_Call_Modes) loop Next (Parm); end loop; pragma Assert (Present (Parm)); Rewrite (Parm, New_Reference_To (RTE (RE_Asynchronous_Call), Loc)); Analyze (Parm); -- Append an if statement to execute the abortable part. -- if Enqueued (Bnn) then Append_To (Stmts, Make_Implicit_If_Statement (N, Condition => Make_Function_Call (Loc, Name => New_Reference_To ( RTE (RE_Enqueued), Loc), Parameter_Associations => New_List ( New_Reference_To (Cancel_Param, Loc))), Then_Statements => Astats)); Abortable_Block := Make_Block_Statement (Loc, Identifier => New_Reference_To (Blkent, Loc), Handled_Statement_Sequence => Make_Handled_Sequence_Of_Statements (Loc, Statements => Stmts), Has_Created_Identifier => True, Is_Asynchronous_Call_Block => True); -- For the JVM call Update_Exception instead of Abort_Undefer. -- See 4jexcept.ads for an explanation. if Hostparm.Java_VM then Target_Undefer := RE_Update_Exception; Undefer_Args := New_List (Make_Function_Call (Loc, Name => New_Occurrence_Of (RTE (RE_Current_Target_Exception), Loc))); else Target_Undefer := RE_Abort_Undefer; end if; Stmts := New_List ( Make_Block_Statement (Loc, Handled_Statement_Sequence => Make_Handled_Sequence_Of_Statements (Loc, Statements => New_List ( Make_Implicit_Label_Declaration (Loc, Defining_Identifier => Blkent, Label_Construct => Abortable_Block), Abortable_Block), -- exception Exception_Handlers => New_List ( Make_Exception_Handler (Loc, -- when Abort_Signal => -- Abort_Undefer.all; Exception_Choices => New_List (New_Reference_To (Stand.Abort_Signal, Loc)), Statements => New_List ( Make_Procedure_Call_Statement (Loc, Name => New_Reference_To ( RTE (Target_Undefer), Loc), Parameter_Associations => Undefer_Args)))))), -- if not Cancelled (Bnn) then -- triggered statements -- end if; Make_Implicit_If_Statement (N, Condition => Make_Op_Not (Loc, Right_Opnd => Make_Function_Call (Loc, Name => New_Occurrence_Of (RTE (RE_Cancelled), Loc), Parameter_Associations => New_List ( New_Occurrence_Of (Cancel_Param, Loc)))), Then_Statements => Tstats)); -- Asynchronous task entry call else if No (Decls) then Decls := New_List; end if; B := Make_Defining_Identifier (Loc, Name_uB); -- Insert declaration of B in declarations of existing block Prepend_To (Decls, Make_Object_Declaration (Loc, Defining_Identifier => B, Object_Definition => New_Reference_To (Standard_Boolean, Loc))); Cancel_Param := Make_Defining_Identifier (Loc, Name_uC); -- Insert declaration of C in declarations of existing block Prepend_To (Decls, Make_Object_Declaration (Loc, Defining_Identifier => Cancel_Param, Object_Definition => New_Reference_To (Standard_Boolean, Loc))); -- Remove and save the call to Call_Simple Stmt := First (Stmts); -- Skip assignments to temporaries created for in-out parameters. -- This makes unwarranted assumptions about the shape of the expanded -- tree for the call, and should be cleaned up ??? while Nkind (Stmt) /= N_Procedure_Call_Statement loop Next (Stmt); end loop; Call := Stmt; -- Create the inner block to protect the abortable part Hdle := New_List ( Make_Exception_Handler (Loc, Exception_Choices => New_List (New_Reference_To (Stand.Abort_Signal, Loc)), Statements => New_List ( Make_Procedure_Call_Statement (Loc, Name => New_Reference_To (RTE (RE_Abort_Undefer), Loc))))); Prepend_To (Astats, Make_Procedure_Call_Statement (Loc, Name => New_Reference_To (RTE (RE_Abort_Undefer), Loc))); Abortable_Block := Make_Block_Statement (Loc, Identifier => New_Reference_To (Blkent, Loc), Handled_Statement_Sequence => Make_Handled_Sequence_Of_Statements (Loc, Statements => Astats), Has_Created_Identifier => True, Is_Asynchronous_Call_Block => True); Insert_After (Call, Make_Block_Statement (Loc, Handled_Statement_Sequence => Make_Handled_Sequence_Of_Statements (Loc, Statements => New_List ( Make_Implicit_Label_Declaration (Loc, Defining_Identifier => Blkent, Label_Construct => Abortable_Block), Abortable_Block), Exception_Handlers => Hdle))); -- Create new call statement Parms := Parameter_Associations (Call); Append_To (Parms, New_Reference_To (RTE (RE_Asynchronous_Call), Loc)); Append_To (Parms, New_Reference_To (B, Loc)); Rewrite (Call, Make_Procedure_Call_Statement (Loc, Name => New_Reference_To (RTE (RE_Task_Entry_Call), Loc), Parameter_Associations => Parms)); -- Construct statement sequence for new block Append_To (Stmts, Make_Implicit_If_Statement (N, Condition => Make_Op_Not (Loc, New_Reference_To (Cancel_Param, Loc)), Then_Statements => Tstats)); -- Protected the call against abortion Prepend_To (Stmts, Make_Procedure_Call_Statement (Loc, Name => New_Reference_To (RTE (RE_Abort_Defer), Loc), Parameter_Associations => Empty_List)); end if; Set_Entry_Cancel_Parameter (Blkent, Cancel_Param); -- The result is the new block Rewrite (N_Orig, Make_Block_Statement (Loc, Declarations => Decls, Handled_Statement_Sequence => Make_Handled_Sequence_Of_Statements (Loc, Stmts))); Analyze (N_Orig); end Expand_N_Asynchronous_Select; ------------------------------------- -- Expand_N_Conditional_Entry_Call -- ------------------------------------- -- The conditional task entry call is converted to a call to -- Task_Entry_Call: -- declare -- B : Boolean; -- P : parms := (parm, parm, parm); -- begin -- Task_Entry_Call -- (acceptor-task, -- entry-index, -- P'Address, -- Conditional_Call, -- B); -- parm := P.param; -- parm := P.param; -- ... -- if B then -- normal-statements -- else -- else-statements -- end if; -- end; -- For a description of the use of P and the assignments after the -- call, see Expand_N_Entry_Call_Statement. Note that the entry call -- of the conditional entry call has already been expanded (by the -- Expand_N_Entry_Call_Statement procedure) as follows: -- declare -- P : parms := (parm, parm, parm); -- begin -- ... info for in-out parameters -- Call_Simple (acceptor-task, entry-index, P'Address); -- parm := P.param; -- parm := P.param; -- ... -- end; -- so the task at hand is to convert the latter expansion into the former -- The conditional protected entry call is converted to a call to -- Protected_Entry_Call: -- declare -- P : parms := (parm, parm, parm); -- Bnn : Communications_Block; -- begin -- Protected_Entry_Call ( -- Object => po._object'Access, -- E => ; -- Uninterpreted_Data => P'Address; -- Mode => Conditional_Call; -- Block => Bnn); -- parm := P.param; -- parm := P.param; -- ... -- if Cancelled (Bnn) then -- else-statements -- else -- normal-statements -- end if; -- end; -- As for tasks, the entry call of the conditional entry call has -- already been expanded (by the Expand_N_Entry_Call_Statement procedure) -- as follows: -- declare -- P : E1_Params := (param, param, param); -- Bnn : Communications_Block; -- begin -- Protected_Entry_Call ( -- Object => po._object'Access, -- E => ; -- Uninterpreted_Data => P'Address; -- Mode => Simple_Call; -- Block => Bnn); -- parm := P.param; -- parm := P.param; -- ... -- end; procedure Expand_N_Conditional_Entry_Call (N : Node_Id) is Loc : constant Source_Ptr := Sloc (N); Alt : constant Node_Id := Entry_Call_Alternative (N); Blk : Node_Id := Entry_Call_Statement (Alt); Transient_Blk : Node_Id; Parms : List_Id; Parm : Node_Id; Call : Node_Id; Stmts : List_Id; B : Entity_Id; Decl : Node_Id; Stmt : Node_Id; begin -- As described above, The entry alternative is transformed into a -- block that contains the gnulli call, and possibly assignment -- statements for in-out parameters. The gnulli call may itself be -- rewritten into a transient block if some unconstrained parameters -- require it. We need to retrieve the call to complete its parameter -- list. Transient_Blk := First_Real_Statement (Handled_Statement_Sequence (Blk)); if Present (Transient_Blk) and then Nkind (Transient_Blk) = N_Block_Statement then Blk := Transient_Blk; end if; Stmts := Statements (Handled_Statement_Sequence (Blk)); Stmt := First (Stmts); while Nkind (Stmt) /= N_Procedure_Call_Statement loop Next (Stmt); end loop; Call := Stmt; Parms := Parameter_Associations (Call); if Is_RTE (Entity (Name (Call)), RE_Protected_Entry_Call) then -- Substitute Conditional_Entry_Call for Simple_Call -- parameter. Parm := First (Parms); while Present (Parm) and then not Is_RTE (Etype (Parm), RE_Call_Modes) loop Next (Parm); end loop; pragma Assert (Present (Parm)); Rewrite (Parm, New_Reference_To (RTE (RE_Conditional_Call), Loc)); Analyze (Parm); -- Find the Communication_Block parameter for the call -- to the Cancelled function. Decl := First (Declarations (Blk)); while Present (Decl) and then not Is_RTE (Etype (Object_Definition (Decl)), RE_Communication_Block) loop Next (Decl); end loop; -- Add an if statement to execute the else part if the call -- does not succeed (as indicated by the Cancelled predicate). Append_To (Stmts, Make_Implicit_If_Statement (N, Condition => Make_Function_Call (Loc, Name => New_Reference_To (RTE (RE_Cancelled), Loc), Parameter_Associations => New_List ( New_Reference_To (Defining_Identifier (Decl), Loc))), Then_Statements => Else_Statements (N), Else_Statements => Statements (Alt))); else B := Make_Defining_Identifier (Loc, Name_uB); -- Insert declaration of B in declarations of existing block if No (Declarations (Blk)) then Set_Declarations (Blk, New_List); end if; Prepend_To (Declarations (Blk), Make_Object_Declaration (Loc, Defining_Identifier => B, Object_Definition => New_Reference_To (Standard_Boolean, Loc))); -- Create new call statement Append_To (Parms, New_Reference_To (RTE (RE_Conditional_Call), Loc)); Append_To (Parms, New_Reference_To (B, Loc)); Rewrite (Call, Make_Procedure_Call_Statement (Loc, Name => New_Reference_To (RTE (RE_Task_Entry_Call), Loc), Parameter_Associations => Parms)); -- Construct statement sequence for new block Append_To (Stmts, Make_Implicit_If_Statement (N, Condition => New_Reference_To (B, Loc), Then_Statements => Statements (Alt), Else_Statements => Else_Statements (N))); end if; -- The result is the new block Rewrite (N, Make_Block_Statement (Loc, Declarations => Declarations (Blk), Handled_Statement_Sequence => Make_Handled_Sequence_Of_Statements (Loc, Stmts))); Analyze (N); end Expand_N_Conditional_Entry_Call; --------------------------------------- -- Expand_N_Delay_Relative_Statement -- --------------------------------------- -- Delay statement is implemented as a procedure call to Delay_For -- defined in Ada.Calendar.Delays in order to reduce the overhead of -- simple delays imposed by the use of Protected Objects. procedure Expand_N_Delay_Relative_Statement (N : Node_Id) is Loc : constant Source_Ptr := Sloc (N); begin Rewrite (N, Make_Procedure_Call_Statement (Loc, Name => New_Reference_To (RTE (RO_CA_Delay_For), Loc), Parameter_Associations => New_List (Expression (N)))); Analyze (N); end Expand_N_Delay_Relative_Statement; ------------------------------------ -- Expand_N_Delay_Until_Statement -- ------------------------------------ -- Delay Until statement is implemented as a procedure call to -- Delay_Until defined in Ada.Calendar.Delays and Ada.Real_Time.Delays. procedure Expand_N_Delay_Until_Statement (N : Node_Id) is Loc : constant Source_Ptr := Sloc (N); Typ : Entity_Id; begin if Is_RTE (Base_Type (Etype (Expression (N))), RO_CA_Time) then Typ := RTE (RO_CA_Delay_Until); else Typ := RTE (RO_RT_Delay_Until); end if; Rewrite (N, Make_Procedure_Call_Statement (Loc, Name => New_Reference_To (Typ, Loc), Parameter_Associations => New_List (Expression (N)))); Analyze (N); end Expand_N_Delay_Until_Statement; ------------------------- -- Expand_N_Entry_Body -- ------------------------- procedure Expand_N_Entry_Body (N : Node_Id) is Loc : constant Source_Ptr := Sloc (N); Dec : constant Node_Id := Parent (Current_Scope); Ent_Formals : constant Node_Id := Entry_Body_Formal_Part (N); Index_Spec : constant Node_Id := Entry_Index_Specification (Ent_Formals); Next_Op : Node_Id; First_Decl : constant Node_Id := First (Declarations (N)); Index_Decl : List_Id; begin -- Add the renamings for private declarations and discriminants Add_Discriminal_Declarations (Declarations (N), Defining_Identifier (Dec), Name_uObject, Loc); Add_Private_Declarations (Declarations (N), Defining_Identifier (Dec), Name_uObject, Loc); if Present (Index_Spec) then Index_Decl := Index_Constant_Declaration (N, Defining_Identifier (Index_Spec), Defining_Identifier (Dec)); -- If the entry has local declarations, insert index declaration -- before them, because the index may be used therein. if Present (First_Decl) then Insert_List_Before (First_Decl, Index_Decl); else Append_List_To (Declarations (N), Index_Decl); end if; end if; -- 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 Set_Privals (Dec, Next_Op, Loc); Set_Discriminals (Dec); end if; end Expand_N_Entry_Body; ----------------------------------- -- Expand_N_Entry_Call_Statement -- ----------------------------------- -- An entry call is expanded into GNARLI calls to implement -- a simple entry call (see Build_Simple_Entry_Call). procedure Expand_N_Entry_Call_Statement (N : Node_Id) is Concval : Node_Id; Ename : Node_Id; Index : Node_Id; begin if No_Run_Time_Mode then Error_Msg_CRT ("entry call", N); return; end if; -- If this entry call is part of an asynchronous select, don't -- expand it here; it will be expanded with the select statement. -- Don't expand timed entry calls either, as they are translated -- into asynchronous entry calls. -- ??? This whole approach is questionable; it may be better -- to go back to allowing the expansion to take place and then -- attempting to fix it up in Expand_N_Asynchronous_Select. -- The tricky part is figuring out whether the expanded -- call is on a task or protected entry. if (Nkind (Parent (N)) /= N_Triggering_Alternative or else N /= Triggering_Statement (Parent (N))) and then (Nkind (Parent (N)) /= N_Entry_Call_Alternative or else N /= Entry_Call_Statement (Parent (N)) or else Nkind (Parent (Parent (N))) /= N_Timed_Entry_Call) then Extract_Entry (N, Concval, Ename, Index); Build_Simple_Entry_Call (N, Concval, Ename, Index); end if; end Expand_N_Entry_Call_Statement; -------------------------------- -- Expand_N_Entry_Declaration -- -------------------------------- -- If there are parameters, then first, each of the formals is marked -- by setting Is_Entry_Formal. Next a record type is built which is -- used to hold the parameter values. The name of this record type is -- entryP where entry is the name of the entry, with an additional -- corresponding access type called entryPA. The record type has matching -- components for each formal (the component names are the same as the -- formal names). For elementary types, the component type matches the -- formal type. For composite types, an access type is declared (with -- the name formalA) which designates the formal type, and the type of -- the component is this access type. Finally the Entry_Component of -- each formal is set to reference the corresponding record component. procedure Expand_N_Entry_Declaration (N : Node_Id) is Loc : constant Source_Ptr := Sloc (N); Entry_Ent : constant Entity_Id := Defining_Identifier (N); Components : List_Id; Formal : Node_Id; Ftype : Entity_Id; Last_Decl : Node_Id; Component : Entity_Id; Ctype : Entity_Id; Decl : Node_Id; Rec_Ent : Entity_Id; Acc_Ent : Entity_Id; begin Formal := First_Formal (Entry_Ent); Last_Decl := N; -- Most processing is done only if parameters are present if Present (Formal) then Components := New_List; -- Loop through formals while Present (Formal) loop Set_Is_Entry_Formal (Formal); Component := Make_Defining_Identifier (Sloc (Formal), Chars (Formal)); Set_Entry_Component (Formal, Component); Set_Entry_Formal (Component, Formal); Ftype := Etype (Formal); -- Declare new access type and then append Ctype := Make_Defining_Identifier (Loc, New_Internal_Name ('A')); Decl := Make_Full_Type_Declaration (Loc, Defining_Identifier => Ctype, Type_Definition => Make_Access_To_Object_Definition (Loc, All_Present => True, Constant_Present => Ekind (Formal) = E_In_Parameter, Subtype_Indication => New_Reference_To (Ftype, Loc))); Insert_After (Last_Decl, Decl); Last_Decl := Decl; Append_To (Components, Make_Component_Declaration (Loc, Defining_Identifier => Component, Component_Definition => Make_Component_Definition (Loc, Aliased_Present => False, Subtype_Indication => New_Reference_To (Ctype, Loc)))); Next_Formal_With_Extras (Formal); end loop; -- Create the Entry_Parameter_Record declaration Rec_Ent := Make_Defining_Identifier (Loc, New_Internal_Name ('P')); Decl := Make_Full_Type_Declaration (Loc, Defining_Identifier => Rec_Ent, Type_Definition => Make_Record_Definition (Loc, Component_List => Make_Component_List (Loc, Component_Items => Components))); Insert_After (Last_Decl, Decl); Last_Decl := Decl; -- Construct and link in the corresponding access type Acc_Ent := Make_Defining_Identifier (Loc, New_Internal_Name ('A')); Set_Entry_Parameters_Type (Entry_Ent, Acc_Ent); Decl := Make_Full_Type_Declaration (Loc, Defining_Identifier => Acc_Ent, Type_Definition => Make_Access_To_Object_Definition (Loc, All_Present => True, Subtype_Indication => New_Reference_To (Rec_Ent, Loc))); Insert_After (Last_Decl, Decl); Last_Decl := Decl; end if; end Expand_N_Entry_Declaration; ----------------------------- -- Expand_N_Protected_Body -- ----------------------------- -- Protected bodies are expanded to the completion of the subprograms -- created for the corresponding protected type. These are a protected -- and unprotected version of each protected subprogram in the object, -- a function to calculate each entry barrier, and a procedure to -- execute the sequence of statements of each protected entry body. -- For example, for protected type ptype: -- function entB -- (O : System.Address; -- E : Protected_Entry_Index) -- return Boolean -- is -- -- -- begin -- return ; -- end entB; -- procedure pprocN (_object : in out poV;...) is -- -- -- begin -- -- end pprocN; -- procedure pproc (_object : in out poV;...) is -- procedure _clean is -- Pn : Boolean; -- begin -- ptypeS (_object, Pn); -- Unlock (_object._object'Access); -- Abort_Undefer.all; -- end _clean; -- begin -- Abort_Defer.all; -- Lock (_object._object'Access); -- pprocN (_object;...); -- at end -- _clean; -- end pproc; -- function pfuncN (_object : poV;...) return Return_Type is -- -- -- begin -- -- end pfuncN; -- function pfunc (_object : poV) return Return_Type is -- procedure _clean is -- begin -- Unlock (_object._object'Access); -- Abort_Undefer.all; -- end _clean; -- begin -- Abort_Defer.all; -- Lock (_object._object'Access); -- return pfuncN (_object); -- at end -- _clean; -- end pfunc; -- procedure entE -- (O : System.Address; -- P : System.Address; -- E : Protected_Entry_Index) -- is -- -- -- type poVP is access poV; -- _Object : ptVP := ptVP!(O); -- begin -- begin -- -- Complete_Entry_Body (_Object._Object); -- exception -- when all others => -- Exceptional_Complete_Entry_Body ( -- _Object._Object, Get_GNAT_Exception); -- end; -- end entE; -- The type poV is the record created for the protected type to hold -- the state of the protected object. procedure Expand_N_Protected_Body (N : Node_Id) is Pid : constant Entity_Id := Corresponding_Spec (N); Has_Entries : Boolean := False; Op_Decl : Node_Id; Op_Body : Node_Id; Op_Id : Entity_Id; New_Op_Body : Node_Id; Current_Node : Node_Id; Num_Entries : Natural := 0; begin if No_Run_Time_Mode then Error_Msg_CRT ("protected body", N); return; end if; if Nkind (Parent (N)) = N_Subunit then -- This is the proper body corresponding to a stub. The declarations -- must be inserted at the point of the stub, which is in the decla- -- rative part of the parent unit. Current_Node := Corresponding_Stub (Parent (N)); else Current_Node := N; end if; Op_Body := First (Declarations (N)); -- The protected body is replaced with the bodies of its -- protected operations, and the declarations for internal objects -- that may have been created for entry family bounds. Rewrite (N, Make_Null_Statement (Sloc (N))); Analyze (N); while Present (Op_Body) loop case Nkind (Op_Body) is when N_Subprogram_Declaration => null; when N_Subprogram_Body => -- Exclude functions created to analyze defaults if not Is_Eliminated (Defining_Entity (Op_Body)) and then not Is_Eliminated (Corresponding_Spec (Op_Body)) then New_Op_Body := Build_Unprotected_Subprogram_Body (Op_Body, Pid); Insert_After (Current_Node, New_Op_Body); Current_Node := New_Op_Body; Analyze (New_Op_Body); Update_Prival_Subtypes (New_Op_Body); -- Build the corresponding protected operation only if -- this is a visible operation of the type, or if it is -- an interrupt handler. Otherwise it is only callable -- from within the object, and the unprotected version -- is sufficient. if Present (Corresponding_Spec (Op_Body)) then Op_Decl := Unit_Declaration_Node (Corresponding_Spec (Op_Body)); if Nkind (Parent (Op_Decl)) = N_Protected_Definition and then (List_Containing (Op_Decl) = Visible_Declarations (Parent (Op_Decl)) or else Is_Interrupt_Handler (Corresponding_Spec (Op_Body))) then New_Op_Body := Build_Protected_Subprogram_Body ( Op_Body, Pid, Specification (New_Op_Body)); Insert_After (Current_Node, New_Op_Body); Analyze (New_Op_Body); end if; end if; end if; when N_Entry_Body => Op_Id := Defining_Identifier (Op_Body); Has_Entries := True; Num_Entries := Num_Entries + 1; New_Op_Body := Build_Protected_Entry (Op_Body, Op_Id, Pid); Insert_After (Current_Node, New_Op_Body); Current_Node := New_Op_Body; Analyze (New_Op_Body); Update_Prival_Subtypes (New_Op_Body); when N_Implicit_Label_Declaration => null; when N_Itype_Reference => Insert_After (Current_Node, New_Copy (Op_Body)); when N_Freeze_Entity => New_Op_Body := New_Copy (Op_Body); if Present (Entity (Op_Body)) and then Freeze_Node (Entity (Op_Body)) = Op_Body then Set_Freeze_Node (Entity (Op_Body), New_Op_Body); end if; Insert_After (Current_Node, New_Op_Body); Current_Node := New_Op_Body; Analyze (New_Op_Body); when N_Pragma => New_Op_Body := New_Copy (Op_Body); Insert_After (Current_Node, New_Op_Body); Current_Node := New_Op_Body; Analyze (New_Op_Body); when N_Object_Declaration => pragma Assert (not Comes_From_Source (Op_Body)); New_Op_Body := New_Copy (Op_Body); Insert_After (Current_Node, New_Op_Body); Current_Node := New_Op_Body; Analyze (New_Op_Body); when others => raise Program_Error; end case; Next (Op_Body); end loop; -- Finally, create the body of the function that maps an entry index -- into the corresponding body index, except when there is no entry, -- or in a ravenscar-like profile (no abort, no entry queue, 1 entry) if Has_Entries and then (Abort_Allowed or else Restriction_Active (No_Entry_Queue) = False or else Num_Entries > 1) then New_Op_Body := Build_Find_Body_Index (Pid); Insert_After (Current_Node, New_Op_Body); Analyze (New_Op_Body); end if; end Expand_N_Protected_Body; ----------------------------------------- -- Expand_N_Protected_Type_Declaration -- ----------------------------------------- -- First we create a corresponding record type declaration used to -- represent values of this protected type. -- The general form of this type declaration is -- type poV (discriminants) is record -- _Object : aliased Protection -- [( [, ])]; -- [entry_family : array (bounds) of Void;] -- -- end record; -- The discriminants are present only if the corresponding protected -- type has discriminants, and they exactly mirror the protected type -- discriminants. The private data fields similarly mirror the -- private declarations of the protected type. -- The Object field is always present. It contains RTS specific data -- used to control the protected object. It is declared as Aliased -- so that it can be passed as a pointer to the RTS. This allows the -- protected record to be referenced within RTS data structures. -- An appropriate Protection type and discriminant are generated. -- The Service field is present for protected objects with entries. It -- contains sufficient information to allow the entry service procedure -- for this object to be called when the object is not known till runtime. -- One entry_family component is present for each entry family in the -- task definition (see Expand_N_Task_Type_Declaration). -- When a protected object is declared, an instance of the protected type -- value record is created. The elaboration of this declaration creates -- the correct bounds for the entry families, and also evaluates the -- priority expression if needed. The initialization routine for -- the protected type itself then calls Initialize_Protection with -- appropriate parameters to initialize the value of the Task_Id field. -- Install_Handlers may be also called if a pragma Attach_Handler applies. -- Note: this record is passed to the subprograms created by the -- expansion of protected subprograms and entries. It is an in parameter -- to protected functions and an in out parameter to procedures and -- entry bodies. The Entity_Id for this created record type is placed -- in the Corresponding_Record_Type field of the associated protected -- type entity. -- Next we create a procedure specifications for protected subprograms -- and entry bodies. For each protected subprograms two subprograms are -- created, an unprotected and a protected version. The unprotected -- version is called from within other operations of the same protected -- object. -- We also build the call to register the procedure if a pragma -- Interrupt_Handler applies. -- A single subprogram is created to service all entry bodies; it has an -- additional boolean out parameter indicating that the previous entry -- call made by the current task was serviced immediately, i.e. not by -- proxy. The O parameter contains a pointer to a record object of the -- type described above. An untyped interface is used here to allow this -- procedure to be called in places where the type of the object to be -- serviced is not known. This must be done, for example, when a call -- that may have been requeued is cancelled; the corresponding object -- must be serviced, but which object that is not known till runtime. -- procedure ptypeS -- (O : System.Address; P : out Boolean); -- procedure pprocN (_object : in out poV); -- procedure pproc (_object : in out poV); -- function pfuncN (_object : poV); -- function pfunc (_object : poV); -- ... -- Note that this must come after the record type declaration, since -- the specs refer to this type. procedure Expand_N_Protected_Type_Declaration (N : Node_Id) is Loc : constant Source_Ptr := Sloc (N); Prottyp : constant Entity_Id := Defining_Identifier (N); Protnm : constant Name_Id := Chars (Prottyp); Pdef : constant Node_Id := Protected_Definition (N); -- This contains two lists; one for visible and one for private decls Rec_Decl : Node_Id; Cdecls : List_Id; Discr_Map : constant Elist_Id := New_Elmt_List; Priv : Node_Id; Pent : Entity_Id; New_Priv : Node_Id; Comp : Node_Id; Comp_Id : Entity_Id; Sub : Node_Id; Current_Node : Node_Id := N; Bdef : Entity_Id := Empty; -- avoid uninit warning Edef : Entity_Id := Empty; -- avoid uninit warning Entries_Aggr : Node_Id; Body_Id : Entity_Id; Body_Arr : Node_Id; E_Count : Int; Object_Comp : Node_Id; procedure Register_Handler; -- for a protected operation that is an interrupt handler, add the -- freeze action that will register it as such. ---------------------- -- Register_Handler -- ---------------------- procedure Register_Handler is -- All semantic checks already done in Sem_Prag Prot_Proc : constant Entity_Id := Defining_Unit_Name (Specification (Current_Node)); Proc_Address : constant Node_Id := Make_Attribute_Reference (Loc, Prefix => New_Reference_To (Prot_Proc, Loc), Attribute_Name => Name_Address); RTS_Call : constant Entity_Id := Make_Procedure_Call_Statement (Loc, Name => New_Reference_To ( RTE (RE_Register_Interrupt_Handler), Loc), Parameter_Associations => New_List (Proc_Address)); begin Append_Freeze_Action (Prot_Proc, RTS_Call); end Register_Handler; -- Start of processing for Expand_N_Protected_Type_Declaration begin if Present (Corresponding_Record_Type (Prottyp)) then return; else Rec_Decl := Build_Corresponding_Record (N, Prottyp, Loc); Cdecls := Component_Items (Component_List (Type_Definition (Rec_Decl))); end if; Qualify_Entity_Names (N); -- If the type has discriminants, their occurrences in the declaration -- have been replaced by the corresponding discriminals. For components -- that are constrained by discriminants, their homologues in the -- corresponding record type must refer to the discriminants of that -- record, so we must apply a new renaming to subtypes_indications: -- protected discriminant => discriminal => record discriminant. -- This replacement is not applied to default expressions, for which -- the discriminal is correct. if Has_Discriminants (Prottyp) then declare Disc : Entity_Id; Decl : Node_Id; begin Disc := First_Discriminant (Prottyp); Decl := First (Discriminant_Specifications (Rec_Decl)); while Present (Disc) loop Append_Elmt (Discriminal (Disc), Discr_Map); Append_Elmt (Defining_Identifier (Decl), Discr_Map); Next_Discriminant (Disc); Next (Decl); end loop; end; end if; -- Fill in the component declarations -- Add components for entry families. For each entry family, -- create an anonymous type declaration with the same size, and -- analyze the type. Collect_Entry_Families (Loc, Cdecls, Current_Node, Prottyp); -- Prepend the _Object field with the right type to the component -- list. We need to compute the number of entries, and in some cases -- the number of Attach_Handler pragmas. declare Ritem : Node_Id; Num_Attach_Handler : Int := 0; Protection_Subtype : Node_Id; Entry_Count_Expr : constant Node_Id := Build_Entry_Count_Expression (Prottyp, Cdecls, Loc); begin if Has_Attach_Handler (Prottyp) then Ritem := First_Rep_Item (Prottyp); while Present (Ritem) loop if Nkind (Ritem) = N_Pragma and then Chars (Ritem) = Name_Attach_Handler then Num_Attach_Handler := Num_Attach_Handler + 1; end if; Next_Rep_Item (Ritem); end loop; if Restricted_Profile then if Has_Entries (Prottyp) then Protection_Subtype := New_Reference_To (RTE (RE_Protection_Entry), Loc); else Protection_Subtype := New_Reference_To (RTE (RE_Protection), Loc); end if; else Protection_Subtype := Make_Subtype_Indication (Sloc => Loc, Subtype_Mark => New_Reference_To (RTE (RE_Static_Interrupt_Protection), Loc), Constraint => Make_Index_Or_Discriminant_Constraint ( Sloc => Loc, Constraints => New_List ( Entry_Count_Expr, Make_Integer_Literal (Loc, Num_Attach_Handler)))); end if; elsif Has_Interrupt_Handler (Prottyp) then Protection_Subtype := Make_Subtype_Indication ( Sloc => Loc, Subtype_Mark => New_Reference_To (RTE (RE_Dynamic_Interrupt_Protection), Loc), Constraint => Make_Index_Or_Discriminant_Constraint ( Sloc => Loc, Constraints => New_List (Entry_Count_Expr))); elsif Has_Entries (Prottyp) then if Abort_Allowed or else Restriction_Active (No_Entry_Queue) = False or else Number_Entries (Prottyp) > 1 then Protection_Subtype := Make_Subtype_Indication ( Sloc => Loc, Subtype_Mark => New_Reference_To (RTE (RE_Protection_Entries), Loc), Constraint => Make_Index_Or_Discriminant_Constraint ( Sloc => Loc, Constraints => New_List (Entry_Count_Expr))); else Protection_Subtype := New_Reference_To (RTE (RE_Protection_Entry), Loc); end if; else Protection_Subtype := New_Reference_To (RTE (RE_Protection), Loc); end if; Object_Comp := Make_Component_Declaration (Loc, Defining_Identifier => Make_Defining_Identifier (Loc, Name_uObject), Component_Definition => Make_Component_Definition (Loc, Aliased_Present => True, Subtype_Indication => Protection_Subtype)); end; pragma Assert (Present (Pdef)); -- Add private field components if Present (Private_Declarations (Pdef)) then Priv := First (Private_Declarations (Pdef)); while Present (Priv) loop if Nkind (Priv) = N_Component_Declaration then Pent := Defining_Identifier (Priv); New_Priv := Make_Component_Declaration (Loc, Defining_Identifier => Make_Defining_Identifier (Sloc (Pent), Chars (Pent)), Component_Definition => Make_Component_Definition (Sloc (Pent), Aliased_Present => False, Subtype_Indication => New_Copy_Tree (Subtype_Indication (Component_Definition (Priv)), Discr_Map)), Expression => Expression (Priv)); Append_To (Cdecls, New_Priv); elsif Nkind (Priv) = N_Subprogram_Declaration then -- Make the unprotected version of the subprogram available -- for expansion of intra object calls. There is need for -- a protected version only if the subprogram is an interrupt -- handler, otherwise this operation can only be called from -- within the body. Sub := Make_Subprogram_Declaration (Loc, Specification => Build_Protected_Sub_Specification (Priv, Prottyp, Unprotected => True)); Insert_After (Current_Node, Sub); Analyze (Sub); Set_Protected_Body_Subprogram (Defining_Unit_Name (Specification (Priv)), Defining_Unit_Name (Specification (Sub))); Current_Node := Sub; if Is_Interrupt_Handler (Defining_Unit_Name (Specification (Priv))) then Sub := Make_Subprogram_Declaration (Loc, Specification => Build_Protected_Sub_Specification (Priv, Prottyp, Unprotected => False)); Insert_After (Current_Node, Sub); Analyze (Sub); Current_Node := Sub; if not Restricted_Profile then Register_Handler; end if; end if; end if; Next (Priv); end loop; end if; -- Put the _Object component after the private component so that it -- be finalized early as required by 9.4 (20) Append_To (Cdecls, Object_Comp); Insert_After (Current_Node, Rec_Decl); Current_Node := Rec_Decl; -- Analyze the record declaration immediately after construction, -- because the initialization procedure is needed for single object -- declarations before the next entity is analyzed (the freeze call -- that generates this initialization procedure is found below). Analyze (Rec_Decl, Suppress => All_Checks); -- Collect pointers to entry bodies and their barriers, to be placed -- in the Entry_Bodies_Array for the type. For each entry/family we -- add an expression to the aggregate which is the initial value of -- this array. The array is declared after all protected subprograms. if Has_Entries (Prottyp) then Entries_Aggr := Make_Aggregate (Loc, Expressions => New_List); else Entries_Aggr := Empty; end if; -- Build two new procedure specifications for each protected -- subprogram; one to call from outside the object and one to -- call from inside. Build a barrier function and an entry -- body action procedure specification for each protected entry. -- Initialize the entry body array. If subprogram is flagged as -- eliminated, do not generate any internal operations. E_Count := 0; Comp := First (Visible_Declarations (Pdef)); while Present (Comp) loop if Nkind (Comp) = N_Subprogram_Declaration and then not Is_Eliminated (Defining_Entity (Comp)) then Sub := Make_Subprogram_Declaration (Loc, Specification => Build_Protected_Sub_Specification (Comp, Prottyp, Unprotected => True)); Insert_After (Current_Node, Sub); Analyze (Sub); Set_Protected_Body_Subprogram (Defining_Unit_Name (Specification (Comp)), Defining_Unit_Name (Specification (Sub))); -- Make the protected version of the subprogram available -- for expansion of external calls. Current_Node := Sub; Sub := Make_Subprogram_Declaration (Loc, Specification => Build_Protected_Sub_Specification (Comp, Prottyp, Unprotected => False)); Insert_After (Current_Node, Sub); Analyze (Sub); Current_Node := Sub; -- If a pragma Interrupt_Handler applies, build and add -- a call to Register_Interrupt_Handler to the freezing actions -- of the protected version (Current_Node) of the subprogram: -- system.interrupts.register_interrupt_handler -- (prot_procP'address); if not Restricted_Profile and then Is_Interrupt_Handler (Defining_Unit_Name (Specification (Comp))) then Register_Handler; end if; elsif Nkind (Comp) = N_Entry_Declaration then E_Count := E_Count + 1; Comp_Id := Defining_Identifier (Comp); Set_Privals_Chain (Comp_Id, New_Elmt_List); Edef := Make_Defining_Identifier (Loc, Build_Selected_Name (Protnm, New_External_Name (Chars (Comp_Id), Suffix_Index => -1), 'E')); Sub := Make_Subprogram_Declaration (Loc, Specification => Build_Protected_Entry_Specification (Edef, Comp_Id, Loc)); Insert_After (Current_Node, Sub); Analyze (Sub); Set_Protected_Body_Subprogram ( Defining_Identifier (Comp), Defining_Unit_Name (Specification (Sub))); Current_Node := Sub; Bdef := Make_Defining_Identifier (Loc, Build_Selected_Name (Protnm, New_External_Name (Chars (Comp_Id), Suffix_Index => -1), 'B')); Sub := Make_Subprogram_Declaration (Loc, Specification => Build_Barrier_Function_Specification (Bdef, Loc)); Insert_After (Current_Node, Sub); Analyze (Sub); Set_Protected_Body_Subprogram (Bdef, Bdef); Set_Barrier_Function (Comp_Id, Bdef); Set_Scope (Bdef, Scope (Comp_Id)); Current_Node := Sub; -- Collect pointers to the protected subprogram and the barrier -- of the current entry, for insertion into Entry_Bodies_Array. Append ( Make_Aggregate (Loc, Expressions => New_List ( Make_Attribute_Reference (Loc, Prefix => New_Reference_To (Bdef, Loc), Attribute_Name => Name_Unrestricted_Access), Make_Attribute_Reference (Loc, Prefix => New_Reference_To (Edef, Loc), Attribute_Name => Name_Unrestricted_Access))), Expressions (Entries_Aggr)); end if; Next (Comp); end loop; -- If there are some private entry declarations, expand it as if they -- were visible entries. if Present (Private_Declarations (Pdef)) then Comp := First (Private_Declarations (Pdef)); while Present (Comp) loop if Nkind (Comp) = N_Entry_Declaration then E_Count := E_Count + 1; Comp_Id := Defining_Identifier (Comp); Set_Privals_Chain (Comp_Id, New_Elmt_List); Edef := Make_Defining_Identifier (Loc, Build_Selected_Name (Protnm, New_External_Name (Chars (Comp_Id), Suffix_Index => -1), 'E')); Sub := Make_Subprogram_Declaration (Loc, Specification => Build_Protected_Entry_Specification (Edef, Comp_Id, Loc)); Insert_After (Current_Node, Sub); Analyze (Sub); Set_Protected_Body_Subprogram ( Defining_Identifier (Comp), Defining_Unit_Name (Specification (Sub))); Current_Node := Sub; Bdef := Make_Defining_Identifier (Loc, Build_Selected_Name (Protnm, New_External_Name (Chars (Comp_Id), Suffix_Index => -1), 'B')); Sub := Make_Subprogram_Declaration (Loc, Specification => Build_Barrier_Function_Specification (Bdef, Loc)); Insert_After (Current_Node, Sub); Analyze (Sub); Set_Protected_Body_Subprogram (Bdef, Bdef); Set_Barrier_Function (Comp_Id, Bdef); Set_Scope (Bdef, Scope (Comp_Id)); Current_Node := Sub; -- Collect pointers to the protected subprogram and the -- barrier of the current entry, for insertion into -- Entry_Bodies_Array. Append ( Make_Aggregate (Loc, Expressions => New_List ( Make_Attribute_Reference (Loc, Prefix => New_Reference_To (Bdef, Loc), Attribute_Name => Name_Unrestricted_Access), Make_Attribute_Reference (Loc, Prefix => New_Reference_To (Edef, Loc), Attribute_Name => Name_Unrestricted_Access))), Expressions (Entries_Aggr)); end if; Next (Comp); end loop; end if; -- Emit declaration for Entry_Bodies_Array, now that the addresses of -- all protected subprograms have been collected. if Has_Entries (Prottyp) then Body_Id := Make_Defining_Identifier (Sloc (Prottyp), New_External_Name (Chars (Prottyp), 'A')); if Abort_Allowed or else Restriction_Active (No_Entry_Queue) = False or else E_Count > 1 then Body_Arr := Make_Object_Declaration (Loc, Defining_Identifier => Body_Id, Aliased_Present => True, Object_Definition => Make_Subtype_Indication (Loc, Subtype_Mark => New_Reference_To ( RTE (RE_Protected_Entry_Body_Array), Loc), Constraint => Make_Index_Or_Discriminant_Constraint (Loc, Constraints => New_List ( Make_Range (Loc, Make_Integer_Literal (Loc, 1), Make_Integer_Literal (Loc, E_Count))))), Expression => Entries_Aggr); else Body_Arr := Make_Object_Declaration (Loc, Defining_Identifier => Body_Id, Aliased_Present => True, Object_Definition => New_Reference_To (RTE (RE_Entry_Body), Loc), Expression => Make_Aggregate (Loc, Expressions => New_List ( Make_Attribute_Reference (Loc, Prefix => New_Reference_To (Bdef, Loc), Attribute_Name => Name_Unrestricted_Access), Make_Attribute_Reference (Loc, Prefix => New_Reference_To (Edef, Loc), Attribute_Name => Name_Unrestricted_Access)))); end if; -- A pointer to this array will be placed in the corresponding -- record by its initialization procedure, so this needs to be -- analyzed here. Insert_After (Current_Node, Body_Arr); Current_Node := Body_Arr; Analyze (Body_Arr); Set_Entry_Bodies_Array (Prottyp, Body_Id); -- Finally, build the function that maps an entry index into the -- corresponding body. A pointer to this function is placed in each -- object of the type. Except for a ravenscar-like profile (no abort, -- no entry queue, 1 entry) if Abort_Allowed or else Restriction_Active (No_Entry_Queue) = False or else E_Count > 1 then Sub := Make_Subprogram_Declaration (Loc, Specification => Build_Find_Body_Index_Spec (Prottyp)); Insert_After (Current_Node, Sub); Analyze (Sub); end if; end if; end Expand_N_Protected_Type_Declaration; -------------------------------- -- Expand_N_Requeue_Statement -- -------------------------------- -- A requeue statement is expanded into one of four GNARLI operations, -- depending on the source and destination (task or protected object). -- In addition, code must be generated to jump around the remainder of -- processing for the original entry and, if the destination is a -- (different) protected object, to attempt to service it. -- The following illustrates the various cases: -- procedure entE -- (O : System.Address; -- P : System.Address; -- E : Protected_Entry_Index) -- is -- -- -- type poVP is access poV; -- _Object : ptVP := ptVP!(O); -- begin -- begin -- -- -- Requeue from one protected entry body to another protected -- -- entry. -- Requeue_Protected_Entry ( -- _object._object'Access, -- new._object'Access, -- E, -- Abort_Present); -- return; -- -- -- Requeue from an entry body to a task entry -- Requeue_Protected_To_Task_Entry ( -- New._task_id, -- E, -- Abort_Present); -- return; -- -- Complete_Entry_Body (_Object._Object); -- exception -- when all others => -- Exceptional_Complete_Entry_Body ( -- _Object._Object, Get_GNAT_Exception); -- end; -- end entE; -- Requeue of a task entry call to a task entry -- Accept_Call (E, Ann); -- -- Requeue_Task_Entry (New._task_id, E, Abort_Present); -- goto Lnn; -- -- <> -- Complete_Rendezvous; -- exception -- when all others => -- Exceptional_Complete_Rendezvous (Get_GNAT_Exception); -- Requeue of a task entry call to a protected entry -- Accept_Call (E, Ann); -- -- Requeue_Task_To_Protected_Entry ( -- new._object'Access, -- E, -- Abort_Present); -- newS (new, Pnn); -- goto Lnn; -- -- <> -- Complete_Rendezvous; -- exception -- when all others => -- Exceptional_Complete_Rendezvous (Get_GNAT_Exception); -- Further details on these expansions can be found in -- Expand_N_Protected_Body and Expand_N_Accept_Statement. procedure Expand_N_Requeue_Statement (N : Node_Id) is Loc : constant Source_Ptr := Sloc (N); Acc_Stat : Node_Id; Concval : Node_Id; Ename : Node_Id; Index : Node_Id; Conctyp : Entity_Id; Oldtyp : Entity_Id; Lab_Node : Node_Id; Rcall : Node_Id; Abortable : Node_Id; Skip_Stat : Node_Id; Self_Param : Node_Id; New_Param : Node_Id; Params : List_Id; RTS_Call : Entity_Id; begin Abortable := New_Occurrence_Of (Boolean_Literals (Abort_Present (N)), Loc); -- Set up the target object Extract_Entry (N, Concval, Ename, Index); Conctyp := Etype (Concval); New_Param := Concurrent_Ref (Concval); -- The target entry index and abortable flag are the same for all cases Params := New_List ( Entry_Index_Expression (Loc, Entity (Ename), Index, Conctyp), Abortable); -- Determine proper GNARLI call and required additional parameters -- Loop to find nearest enclosing task type or protected type Oldtyp := Current_Scope; loop if Is_Task_Type (Oldtyp) then if Is_Task_Type (Conctyp) then RTS_Call := RTE (RE_Requeue_Task_Entry); else pragma Assert (Is_Protected_Type (Conctyp)); RTS_Call := RTE (RE_Requeue_Task_To_Protected_Entry); New_Param := Make_Attribute_Reference (Loc, Prefix => New_Param, Attribute_Name => Name_Unchecked_Access); end if; Prepend (New_Param, Params); exit; elsif Is_Protected_Type (Oldtyp) then Self_Param := Make_Attribute_Reference (Loc, Prefix => Concurrent_Ref (New_Occurrence_Of (Oldtyp, Loc)), Attribute_Name => Name_Unchecked_Access); if Is_Task_Type (Conctyp) then RTS_Call := RTE (RE_Requeue_Protected_To_Task_Entry); else pragma Assert (Is_Protected_Type (Conctyp)); RTS_Call := RTE (RE_Requeue_Protected_Entry); New_Param := Make_Attribute_Reference (Loc, Prefix => New_Param, Attribute_Name => Name_Unchecked_Access); end if; Prepend (New_Param, Params); Prepend (Self_Param, Params); exit; -- If neither task type or protected type, must be in some -- inner enclosing block, so move on out else Oldtyp := Scope (Oldtyp); end if; end loop; -- Create the GNARLI call Rcall := Make_Procedure_Call_Statement (Loc, Name => New_Occurrence_Of (RTS_Call, Loc), Parameter_Associations => Params); Rewrite (N, Rcall); Analyze (N); if Is_Protected_Type (Oldtyp) then -- Build the return statement to skip the rest of the entry body Skip_Stat := Make_Return_Statement (Loc); else -- If the requeue is within a task, find the end label of the -- enclosing accept statement. Acc_Stat := Parent (N); while Nkind (Acc_Stat) /= N_Accept_Statement loop Acc_Stat := Parent (Acc_Stat); end loop; -- The last statement is the second label, used for completing the -- rendezvous the usual way. -- The label we are looking for is right before it. Lab_Node := Prev (Last (Statements (Handled_Statement_Sequence (Acc_Stat)))); pragma Assert (Nkind (Lab_Node) = N_Label); -- Build the goto statement to skip the rest of the accept -- statement. Skip_Stat := Make_Goto_Statement (Loc, Name => New_Occurrence_Of (Entity (Identifier (Lab_Node)), Loc)); end if; Set_Analyzed (Skip_Stat); Insert_After (N, Skip_Stat); end Expand_N_Requeue_Statement; ------------------------------- -- Expand_N_Selective_Accept -- ------------------------------- procedure Expand_N_Selective_Accept (N : Node_Id) is Loc : constant Source_Ptr := Sloc (N); Alts : constant List_Id := Select_Alternatives (N); -- Note: in the below declarations a lot of new lists are allocated -- unconditionally which may well not end up being used. That's -- not a good idea since it wastes space gratuitously ??? Accept_Case : List_Id; Accept_List : constant List_Id := New_List; Alt : Node_Id; Alt_List : constant List_Id := New_List; Alt_Stats : List_Id; Ann : Entity_Id := Empty; Block : Node_Id; Check_Guard : Boolean := True; Decls : constant List_Id := New_List; Stats : constant List_Id := New_List; Body_List : constant List_Id := New_List; Trailing_List : constant List_Id := New_List; Choices : List_Id; Else_Present : Boolean := False; Terminate_Alt : Node_Id := Empty; Select_Mode : Node_Id; Delay_Case : List_Id; Delay_Count : Integer := 0; Delay_Val : Entity_Id; Delay_Index : Entity_Id; Delay_Min : Entity_Id; Delay_Num : Int := 1; Delay_Alt_List : List_Id := New_List; Delay_List : constant List_Id := New_List; D : Entity_Id; M : Entity_Id; First_Delay : Boolean := True; Guard_Open : Entity_Id; End_Lab : Node_Id; Index : Int := 1; Lab : Node_Id; Num_Alts : Int; Num_Accept : Nat := 0; Proc : Node_Id; Q : Node_Id; Time_Type : Entity_Id; X : Node_Id; Select_Call : Node_Id; Qnam : constant Entity_Id := Make_Defining_Identifier (Loc, New_External_Name ('S', 0)); Xnam : constant Entity_Id := Make_Defining_Identifier (Loc, New_External_Name ('J', 1)); ----------------------- -- Local subprograms -- ----------------------- function Accept_Or_Raise return List_Id; -- For the rare case where delay alternatives all have guards, and -- all of them are closed, it is still possible that there were open -- accept alternatives with no callers. We must reexamine the -- Accept_List, and execute a selective wait with no else if some -- accept is open. If none, we raise program_error. procedure Add_Accept (Alt : Node_Id); -- Process a single accept statement in a select alternative. Build -- procedure for body of accept, and add entry to dispatch table with -- expression for guard, in preparation for call to run time select. function Make_And_Declare_Label (Num : Int) return Node_Id; -- Manufacture a label using Num as a serial number and declare it. -- The declaration is appended to Decls. The label marks the trailing -- statements of an accept or delay alternative. function Make_Select_Call (Select_Mode : Entity_Id) return Node_Id; -- Build call to Selective_Wait runtime routine procedure Process_Delay_Alternative (Alt : Node_Id; Index : Int); -- Add code to compare value of delay with previous values, and -- generate case entry for trailing statements. procedure Process_Accept_Alternative (Alt : Node_Id; Index : Int; Proc : Node_Id); -- Add code to call corresponding procedure, and branch to -- trailing statements, if any. --------------------- -- Accept_Or_Raise -- --------------------- function Accept_Or_Raise return List_Id is Cond : Node_Id; Stats : List_Id; J : constant Entity_Id := Make_Defining_Identifier (Loc, New_Internal_Name ('J')); begin -- We generate the following: -- for J in q'range loop -- if q(J).S /=null_task_entry then -- selective_wait (simple_mode,...); -- done := True; -- exit; -- end if; -- end loop; -- -- if no rendez_vous then -- raise program_error; -- end if; -- Note that the code needs to know that the selector name -- in an Accept_Alternative is named S. Cond := Make_Op_Ne (Loc, Left_Opnd => Make_Selected_Component (Loc, Prefix => Make_Indexed_Component (Loc, Prefix => New_Reference_To (Qnam, Loc), Expressions => New_List (New_Reference_To (J, Loc))), Selector_Name => Make_Identifier (Loc, Name_S)), Right_Opnd => New_Reference_To (RTE (RE_Null_Task_Entry), Loc)); Stats := New_List ( Make_Implicit_Loop_Statement (N, Identifier => Empty, Iteration_Scheme => Make_Iteration_Scheme (Loc, Loop_Parameter_Specification => Make_Loop_Parameter_Specification (Loc, Defining_Identifier => J, Discrete_Subtype_Definition => Make_Attribute_Reference (Loc, Prefix => New_Reference_To (Qnam, Loc), Attribute_Name => Name_Range, Expressions => New_List ( Make_Integer_Literal (Loc, 1))))), Statements => New_List ( Make_Implicit_If_Statement (N, Condition => Cond, Then_Statements => New_List ( Make_Select_Call ( New_Reference_To (RTE (RE_Simple_Mode), Loc)), Make_Exit_Statement (Loc)))))); Append_To (Stats, Make_Raise_Program_Error (Loc, Condition => Make_Op_Eq (Loc, Left_Opnd => New_Reference_To (Xnam, Loc), Right_Opnd => New_Reference_To (RTE (RE_No_Rendezvous), Loc)), Reason => PE_All_Guards_Closed)); return Stats; end Accept_Or_Raise; ---------------- -- Add_Accept -- ---------------- procedure Add_Accept (Alt : Node_Id) is Acc_Stm : constant Node_Id := Accept_Statement (Alt); Ename : constant Node_Id := Entry_Direct_Name (Acc_Stm); Eent : constant Entity_Id := Entity (Ename); Index : constant Node_Id := Entry_Index (Acc_Stm); Null_Body : Node_Id; Proc_Body : Node_Id; PB_Ent : Entity_Id; Expr : Node_Id; Call : Node_Id; begin if No (Ann) then Ann := Node (Last_Elmt (Accept_Address (Eent))); end if; if Present (Condition (Alt)) then Expr := Make_Conditional_Expression (Loc, New_List ( Condition (Alt), Entry_Index_Expression (Loc, Eent, Index, Scope (Eent)), New_Reference_To (RTE (RE_Null_Task_Entry), Loc))); else Expr := Entry_Index_Expression (Loc, Eent, Index, Scope (Eent)); end if; if Present (Handled_Statement_Sequence (Accept_Statement (Alt))) then Null_Body := New_Reference_To (Standard_False, Loc); if Abort_Allowed then Call := Make_Procedure_Call_Statement (Loc, Name => New_Reference_To (RTE (RE_Abort_Undefer), Loc)); Insert_Before (First (Statements (Handled_Statement_Sequence ( Accept_Statement (Alt)))), Call); Analyze (Call); end if; PB_Ent := Make_Defining_Identifier (Sloc (Ename), New_External_Name (Chars (Ename), 'A', Num_Accept)); Set_Needs_Debug_Info (PB_Ent, Comes_From_Source (Alt)); Proc_Body := Make_Subprogram_Body (Loc, Specification => Make_Procedure_Specification (Loc, Defining_Unit_Name => PB_Ent), Declarations => Declarations (Acc_Stm), Handled_Statement_Sequence => Build_Accept_Body (Accept_Statement (Alt))); -- During the analysis of the body of the accept statement, any -- zero cost exception handler records were collected in the -- Accept_Handler_Records field of the N_Accept_Alternative -- node. This is where we move them to where they belong, -- namely the newly created procedure. Set_Handler_Records (PB_Ent, Accept_Handler_Records (Alt)); Append (Proc_Body, Body_List); else Null_Body := New_Reference_To (Standard_True, Loc); -- if accept statement has declarations, insert above, given -- that we are not creating a body for the accept. if Present (Declarations (Acc_Stm)) then Insert_Actions (N, Declarations (Acc_Stm)); end if; end if; Append_To (Accept_List, Make_Aggregate (Loc, Expressions => New_List (Null_Body, Expr))); Num_Accept := Num_Accept + 1; end Add_Accept; ---------------------------- -- Make_And_Declare_Label -- ---------------------------- function Make_And_Declare_Label (Num : Int) return Node_Id is Lab_Id : Node_Id; begin Lab_Id := Make_Identifier (Loc, New_External_Name ('L', Num)); Lab := Make_Label (Loc, Lab_Id); Append_To (Decls, Make_Implicit_Label_Declaration (Loc, Defining_Identifier => Make_Defining_Identifier (Loc, Chars (Lab_Id)), Label_Construct => Lab)); return Lab; end Make_And_Declare_Label; ---------------------- -- Make_Select_Call -- ---------------------- function Make_Select_Call (Select_Mode : Entity_Id) return Node_Id is Params : constant List_Id := New_List; begin Append ( Make_Attribute_Reference (Loc, Prefix => New_Reference_To (Qnam, Loc), Attribute_Name => Name_Unchecked_Access), Params); Append (Select_Mode, Params); Append (New_Reference_To (Ann, Loc), Params); Append (New_Reference_To (Xnam, Loc), Params); return Make_Procedure_Call_Statement (Loc, Name => New_Reference_To (RTE (RE_Selective_Wait), Loc), Parameter_Associations => Params); end Make_Select_Call; -------------------------------- -- Process_Accept_Alternative -- -------------------------------- procedure Process_Accept_Alternative (Alt : Node_Id; Index : Int; Proc : Node_Id) is Choices : List_Id := No_List; Alt_Stats : List_Id; begin Adjust_Condition (Condition (Alt)); Alt_Stats := No_List; if Present (Handled_Statement_Sequence (Accept_Statement (Alt))) then Choices := New_List ( Make_Integer_Literal (Loc, Index)); Alt_Stats := New_List ( Make_Procedure_Call_Statement (Loc, Name => New_Reference_To ( Defining_Unit_Name (Specification (Proc)), Loc))); end if; if Statements (Alt) /= Empty_List then if No (Alt_Stats) then -- Accept with no body, followed by trailing statements Choices := New_List ( Make_Integer_Literal (Loc, Index)); Alt_Stats := New_List; end if; -- After the call, if any, branch to to trailing statements. -- We create a label for each, as well as the corresponding -- label declaration. Lab := Make_And_Declare_Label (Index); Append_To (Alt_Stats, Make_Goto_Statement (Loc, Name => New_Copy (Identifier (Lab)))); Append (Lab, Trailing_List); Append_List (Statements (Alt), Trailing_List); Append_To (Trailing_List, Make_Goto_Statement (Loc, Name => New_Copy (Identifier (End_Lab)))); end if; if Present (Alt_Stats) then -- Procedure call. and/or trailing statements Append_To (Alt_List, Make_Case_Statement_Alternative (Loc, Discrete_Choices => Choices, Statements => Alt_Stats)); end if; end Process_Accept_Alternative; ------------------------------- -- Process_Delay_Alternative -- ------------------------------- procedure Process_Delay_Alternative (Alt : Node_Id; Index : Int) is Choices : List_Id; Cond : Node_Id; Delay_Alt : List_Id; begin -- Deal with C/Fortran boolean as delay condition Adjust_Condition (Condition (Alt)); -- Determine the smallest specified delay -- for each delay alternative generate: -- if guard-expression then -- Delay_Val := delay-expression; -- Guard_Open := True; -- if Delay_Val < Delay_Min then -- Delay_Min := Delay_Val; -- Delay_Index := Index; -- end if; -- end if; -- The enclosing if-statement is omitted if there is no guard if Delay_Count = 1 or else First_Delay then First_Delay := False; Delay_Alt := New_List ( Make_Assignment_Statement (Loc, Name => New_Reference_To (Delay_Min, Loc), Expression => Expression (Delay_Statement (Alt)))); if Delay_Count > 1 then Append_To (Delay_Alt, Make_Assignment_Statement (Loc, Name => New_Reference_To (Delay_Index, Loc), Expression => Make_Integer_Literal (Loc, Index))); end if; else Delay_Alt := New_List ( Make_Assignment_Statement (Loc, Name => New_Reference_To (Delay_Val, Loc), Expression => Expression (Delay_Statement (Alt)))); if Time_Type = Standard_Duration then Cond := Make_Op_Lt (Loc, Left_Opnd => New_Reference_To (Delay_Val, Loc), Right_Opnd => New_Reference_To (Delay_Min, Loc)); else -- The scope of the time type must define a comparison -- operator. The scope itself may not be visible, so we -- construct a node with entity information to insure that -- semantic analysis can find the proper operator. Cond := Make_Function_Call (Loc, Name => Make_Selected_Component (Loc, Prefix => New_Reference_To (Scope (Time_Type), Loc), Selector_Name => Make_Operator_Symbol (Loc, Chars => Name_Op_Lt, Strval => No_String)), Parameter_Associations => New_List ( New_Reference_To (Delay_Val, Loc), New_Reference_To (Delay_Min, Loc))); Set_Entity (Prefix (Name (Cond)), Scope (Time_Type)); end if; Append_To (Delay_Alt, Make_Implicit_If_Statement (N, Condition => Cond, Then_Statements => New_List ( Make_Assignment_Statement (Loc, Name => New_Reference_To (Delay_Min, Loc), Expression => New_Reference_To (Delay_Val, Loc)), Make_Assignment_Statement (Loc, Name => New_Reference_To (Delay_Index, Loc), Expression => Make_Integer_Literal (Loc, Index))))); end if; if Check_Guard then Append_To (Delay_Alt, Make_Assignment_Statement (Loc, Name => New_Reference_To (Guard_Open, Loc), Expression => New_Reference_To (Standard_True, Loc))); end if; if Present (Condition (Alt)) then Delay_Alt := New_List ( Make_Implicit_If_Statement (N, Condition => Condition (Alt), Then_Statements => Delay_Alt)); end if; Append_List (Delay_Alt, Delay_List); -- If the delay alternative has a statement part, add a -- choice to the case statements for delays. if Present (Statements (Alt)) then if Delay_Count = 1 then Append_List (Statements (Alt), Delay_Alt_List); else Choices := New_List ( Make_Integer_Literal (Loc, Index)); Append_To (Delay_Alt_List, Make_Case_Statement_Alternative (Loc, Discrete_Choices => Choices, Statements => Statements (Alt))); end if; elsif Delay_Count = 1 then -- If the single delay has no trailing statements, add a branch -- to the exit label to the selective wait. Delay_Alt_List := New_List ( Make_Goto_Statement (Loc, Name => New_Copy (Identifier (End_Lab)))); end if; end Process_Delay_Alternative; -- Start of processing for Expand_N_Selective_Accept begin -- First insert some declarations before the select. The first is: -- Ann : Address -- This variable holds the parameters passed to the accept body. This -- declaration has already been inserted by the time we get here by -- a call to Expand_Accept_Declarations made from the semantics when -- processing the first accept statement contained in the select. We -- can find this entity as Accept_Address (E), where E is any of the -- entries references by contained accept statements. -- The first step is to scan the list of Selective_Accept_Statements -- to find this entity, and also count the number of accepts, and -- determine if terminated, delay or else is present: Num_Alts := 0; Alt := First (Alts); while Present (Alt) loop if Nkind (Alt) = N_Accept_Alternative then Add_Accept (Alt); elsif Nkind (Alt) = N_Delay_Alternative then Delay_Count := Delay_Count + 1; -- If the delays are relative delays, the delay expressions have -- type Standard_Duration. Otherwise they must have some time type -- recognized by GNAT. if Nkind (Delay_Statement (Alt)) = N_Delay_Relative_Statement then Time_Type := Standard_Duration; else Time_Type := Etype (Expression (Delay_Statement (Alt))); if Is_RTE (Base_Type (Etype (Time_Type)), RO_CA_Time) or else Is_RTE (Base_Type (Etype (Time_Type)), RO_RT_Time) then null; else Error_Msg_NE ( "& is not a time type ('R'M 9.6(6))", Expression (Delay_Statement (Alt)), Time_Type); Time_Type := Standard_Duration; Set_Etype (Expression (Delay_Statement (Alt)), Any_Type); end if; end if; if No (Condition (Alt)) then -- This guard will always be open Check_Guard := False; end if; elsif Nkind (Alt) = N_Terminate_Alternative then Adjust_Condition (Condition (Alt)); Terminate_Alt := Alt; end if; Num_Alts := Num_Alts + 1; Next (Alt); end loop; Else_Present := Present (Else_Statements (N)); -- At the same time (see procedure Add_Accept) we build the accept list: -- Qnn : Accept_List (1 .. num-select) := ( -- (null-body, entry-index), -- (null-body, entry-index), -- .. -- (null_body, entry-index)); -- In the above declaration, null-body is True if the corresponding -- accept has no body, and false otherwise. The entry is either the -- entry index expression if there is no guard, or if a guard is -- present, then a conditional expression of the form: -- (if guard then entry-index else Null_Task_Entry) -- If a guard is statically known to be false, the entry can simply -- be omitted from the accept list. Q := Make_Object_Declaration (Loc, Defining_Identifier => Qnam, Object_Definition => New_Reference_To (RTE (RE_Accept_List), Loc), Aliased_Present => True, Expression => Make_Qualified_Expression (Loc, Subtype_Mark => New_Reference_To (RTE (RE_Accept_List), Loc), Expression => Make_Aggregate (Loc, Expressions => Accept_List))); Append (Q, Decls); -- Then we declare the variable that holds the index for the accept -- that will be selected for service: -- Xnn : Select_Index; X := Make_Object_Declaration (Loc, Defining_Identifier => Xnam, Object_Definition => New_Reference_To (RTE (RE_Select_Index), Loc), Expression => New_Reference_To (RTE (RE_No_Rendezvous), Loc)); Append (X, Decls); -- After this follow procedure declarations for each accept body -- procedure Pnn is -- begin -- ... -- end; -- where the ... are statements from the corresponding procedure body. -- No parameters are involved, since the parameters are passed via Ann -- and the parameter references have already been expanded to be direct -- references to Ann (see Exp_Ch2.Expand_Entry_Parameter). Furthermore, -- any embedded tasking statements (which would normally be illegal in -- procedures, have been converted to calls to the tasking runtime so -- there is no problem in putting them into procedures. -- The original accept statement has been expanded into a block in -- the same fashion as for simple accepts (see Build_Accept_Body). -- Note: we don't really need to build these procedures for the case -- where no delay statement is present, but it is just as easy to -- build them unconditionally, and not significantly inefficient, -- since if they are short they will be inlined anyway. -- The procedure declarations have been assembled in Body_List -- If delays are present, we must compute the required delay. -- We first generate the declarations: -- Delay_Index : Boolean := 0; -- Delay_Min : Some_Time_Type.Time; -- Delay_Val : Some_Time_Type.Time; -- Delay_Index will be set to the index of the minimum delay, i.e. the -- active delay that is actually chosen as the basis for the possible -- delay if an immediate rendez-vous is not possible. -- In the most common case there is a single delay statement, and this -- is handled specially. if Delay_Count > 0 then -- Generate the required declarations Delay_Val := Make_Defining_Identifier (Loc, New_External_Name ('D', 1)); Delay_Index := Make_Defining_Identifier (Loc, New_External_Name ('D', 2)); Delay_Min := Make_Defining_Identifier (Loc, New_External_Name ('D', 3)); Append_To (Decls, Make_Object_Declaration (Loc, Defining_Identifier => Delay_Val, Object_Definition => New_Reference_To (Time_Type, Loc))); Append_To (Decls, Make_Object_Declaration (Loc, Defining_Identifier => Delay_Index, Object_Definition => New_Reference_To (Standard_Integer, Loc), Expression => Make_Integer_Literal (Loc, 0))); Append_To (Decls, Make_Object_Declaration (Loc, Defining_Identifier => Delay_Min, Object_Definition => New_Reference_To (Time_Type, Loc), Expression => Unchecked_Convert_To (Time_Type, Make_Attribute_Reference (Loc, Prefix => New_Occurrence_Of (Underlying_Type (Time_Type), Loc), Attribute_Name => Name_Last)))); -- Create Duration and Delay_Mode objects used for passing a delay -- value to RTS D := Make_Defining_Identifier (Loc, New_Internal_Name ('D')); M := Make_Defining_Identifier (Loc, New_Internal_Name ('M')); declare Discr : Entity_Id; begin -- Note that these values are defined in s-osprim.ads and must -- be kept in sync: -- -- Relative : constant := 0; -- Absolute_Calendar : constant := 1; -- Absolute_RT : constant := 2; if Time_Type = Standard_Duration then Discr := Make_Integer_Literal (Loc, 0); elsif Is_RTE (Base_Type (Etype (Time_Type)), RO_CA_Time) then Discr := Make_Integer_Literal (Loc, 1); else pragma Assert (Is_RTE (Base_Type (Etype (Time_Type)), RO_RT_Time)); Discr := Make_Integer_Literal (Loc, 2); end if; Append_To (Decls, Make_Object_Declaration (Loc, Defining_Identifier => D, Object_Definition => New_Reference_To (Standard_Duration, Loc))); Append_To (Decls, Make_Object_Declaration (Loc, Defining_Identifier => M, Object_Definition => New_Reference_To (Standard_Integer, Loc), Expression => Discr)); end; if Check_Guard then Guard_Open := Make_Defining_Identifier (Loc, New_External_Name ('G', 1)); Append_To (Decls, Make_Object_Declaration (Loc, Defining_Identifier => Guard_Open, Object_Definition => New_Reference_To (Standard_Boolean, Loc), Expression => New_Reference_To (Standard_False, Loc))); end if; -- Delay_Count is zero, don't need M and D set (suppress warning) else M := Empty; D := Empty; end if; if Present (Terminate_Alt) then -- If the terminate alternative guard is False, use -- Simple_Mode; otherwise use Terminate_Mode. if Present (Condition (Terminate_Alt)) then Select_Mode := Make_Conditional_Expression (Loc, New_List (Condition (Terminate_Alt), New_Reference_To (RTE (RE_Terminate_Mode), Loc), New_Reference_To (RTE (RE_Simple_Mode), Loc))); else Select_Mode := New_Reference_To (RTE (RE_Terminate_Mode), Loc); end if; elsif Else_Present or Delay_Count > 0 then Select_Mode := New_Reference_To (RTE (RE_Else_Mode), Loc); else Select_Mode := New_Reference_To (RTE (RE_Simple_Mode), Loc); end if; Select_Call := Make_Select_Call (Select_Mode); Append (Select_Call, Stats); -- Now generate code to act on the result. There is an entry -- in this case for each accept statement with a non-null body, -- followed by a branch to the statements that follow the Accept. -- In the absence of delay alternatives, we generate: -- case X is -- when No_Rendezvous => -- omitted if simple mode -- goto Lab0; -- when 1 => -- P1n; -- goto Lab1; -- when 2 => -- P2n; -- goto Lab2; -- when others => -- goto Exit; -- end case; -- -- Lab0: Else_Statements; -- goto exit; -- Lab1: Trailing_Statements1; -- goto Exit; -- -- Lab2: Trailing_Statements2; -- goto Exit; -- ... -- Exit: -- Generate label for common exit End_Lab := Make_And_Declare_Label (Num_Alts + 1); -- First entry is the default case, when no rendezvous is possible Choices := New_List (New_Reference_To (RTE (RE_No_Rendezvous), Loc)); if Else_Present then -- If no rendezvous is possible, the else part is executed Lab := Make_And_Declare_Label (0); Alt_Stats := New_List ( Make_Goto_Statement (Loc, Name => New_Copy (Identifier (Lab)))); Append (Lab, Trailing_List); Append_List (Else_Statements (N), Trailing_List); Append_To (Trailing_List, Make_Goto_Statement (Loc, Name => New_Copy (Identifier (End_Lab)))); else Alt_Stats := New_List ( Make_Goto_Statement (Loc, Name => New_Copy (Identifier (End_Lab)))); end if; Append_To (Alt_List, Make_Case_Statement_Alternative (Loc, Discrete_Choices => Choices, Statements => Alt_Stats)); -- We make use of the fact that Accept_Index is an integer type, -- and generate successive literals for entries for each accept. -- Only those for which there is a body or trailing statements are -- given a case entry. Alt := First (Select_Alternatives (N)); Proc := First (Body_List); while Present (Alt) loop if Nkind (Alt) = N_Accept_Alternative then Process_Accept_Alternative (Alt, Index, Proc); Index := Index + 1; if Present (Handled_Statement_Sequence (Accept_Statement (Alt))) then Next (Proc); end if; elsif Nkind (Alt) = N_Delay_Alternative then Process_Delay_Alternative (Alt, Delay_Num); Delay_Num := Delay_Num + 1; end if; Next (Alt); end loop; -- An others choice is always added to the main case, as well -- as the delay case (to satisfy the compiler). Append_To (Alt_List, Make_Case_Statement_Alternative (Loc, Discrete_Choices => New_List (Make_Others_Choice (Loc)), Statements => New_List (Make_Goto_Statement (Loc, Name => New_Copy (Identifier (End_Lab)))))); Accept_Case := New_List ( Make_Case_Statement (Loc, Expression => New_Reference_To (Xnam, Loc), Alternatives => Alt_List)); Append_List (Trailing_List, Accept_Case); Append (End_Lab, Accept_Case); Append_List (Body_List, Decls); -- Construct case statement for trailing statements of delay -- alternatives, if there are several of them. if Delay_Count > 1 then Append_To (Delay_Alt_List, Make_Case_Statement_Alternative (Loc, Discrete_Choices => New_List (Make_Others_Choice (Loc)), Statements => New_List (Make_Null_Statement (Loc)))); Delay_Case := New_List ( Make_Case_Statement (Loc, Expression => New_Reference_To (Delay_Index, Loc), Alternatives => Delay_Alt_List)); else Delay_Case := Delay_Alt_List; end if; -- If there are no delay alternatives, we append the case statement -- to the statement list. if Delay_Count = 0 then Append_List (Accept_Case, Stats); -- Delay alternatives present else -- If delay alternatives are present we generate: -- find minimum delay. -- DX := minimum delay; -- M := ; -- Timed_Selective_Wait (Q'Unchecked_Access, Delay_Mode, P, -- DX, MX, X); -- -- if X = No_Rendezvous then -- case statement for delay statements. -- else -- case statement for accept alternatives. -- end if; declare Cases : Node_Id; Stmt : Node_Id; Parms : List_Id; Parm : Node_Id; Conv : Node_Id; begin -- The type of the delay expression is known to be legal if Time_Type = Standard_Duration then Conv := New_Reference_To (Delay_Min, Loc); elsif Is_RTE (Base_Type (Etype (Time_Type)), RO_CA_Time) then Conv := Make_Function_Call (Loc, New_Reference_To (RTE (RO_CA_To_Duration), Loc), New_List (New_Reference_To (Delay_Min, Loc))); else pragma Assert (Is_RTE (Base_Type (Etype (Time_Type)), RO_RT_Time)); Conv := Make_Function_Call (Loc, New_Reference_To (RTE (RO_RT_To_Duration), Loc), New_List (New_Reference_To (Delay_Min, Loc))); end if; Stmt := Make_Assignment_Statement (Loc, Name => New_Reference_To (D, Loc), Expression => Conv); -- Change the value for Accept_Modes. (Else_Mode -> Delay_Mode) Parms := Parameter_Associations (Select_Call); Parm := First (Parms); while Present (Parm) and then Parm /= Select_Mode loop Next (Parm); end loop; pragma Assert (Present (Parm)); Rewrite (Parm, New_Reference_To (RTE (RE_Delay_Mode), Loc)); Analyze (Parm); -- Prepare two new parameters of Duration and Delay_Mode type -- which represent the value and the mode of the minimum delay. Next (Parm); Insert_After (Parm, New_Reference_To (M, Loc)); Insert_After (Parm, New_Reference_To (D, Loc)); -- Create a call to RTS Rewrite (Select_Call, Make_Procedure_Call_Statement (Loc, Name => New_Reference_To (RTE (RE_Timed_Selective_Wait), Loc), Parameter_Associations => Parms)); -- This new call should follow the calculation of the -- minimum delay. Insert_List_Before (Select_Call, Delay_List); if Check_Guard then Stmt := Make_Implicit_If_Statement (N, Condition => New_Reference_To (Guard_Open, Loc), Then_Statements => New_List (New_Copy_Tree (Stmt), New_Copy_Tree (Select_Call)), Else_Statements => Accept_Or_Raise); Rewrite (Select_Call, Stmt); else Insert_Before (Select_Call, Stmt); end if; Cases := Make_Implicit_If_Statement (N, Condition => Make_Op_Eq (Loc, Left_Opnd => New_Reference_To (Xnam, Loc), Right_Opnd => New_Reference_To (RTE (RE_No_Rendezvous), Loc)), Then_Statements => Delay_Case, Else_Statements => Accept_Case); Append (Cases, Stats); end; end if; -- Replace accept statement with appropriate block Block := Make_Block_Statement (Loc, Declarations => Decls, Handled_Statement_Sequence => Make_Handled_Sequence_Of_Statements (Loc, Statements => Stats)); Rewrite (N, Block); Analyze (N); -- Note: have to worry more about abort deferral in above code ??? -- Final step is to unstack the Accept_Address entries for all accept -- statements appearing in accept alternatives in the select statement Alt := First (Alts); while Present (Alt) loop if Nkind (Alt) = N_Accept_Alternative then Remove_Last_Elmt (Accept_Address (Entity (Entry_Direct_Name (Accept_Statement (Alt))))); end if; Next (Alt); end loop; end Expand_N_Selective_Accept; -------------------------------------- -- Expand_N_Single_Task_Declaration -- -------------------------------------- -- Single task declarations should never be present after semantic -- analysis, since we expect them to be replaced by a declaration of -- an anonymous task type, followed by a declaration of the task -- object. We include this routine to make sure that is happening! procedure Expand_N_Single_Task_Declaration (N : Node_Id) is begin raise Program_Error; end Expand_N_Single_Task_Declaration; ------------------------ -- Expand_N_Task_Body -- ------------------------ -- Given a task body -- task body tname is -- -- begin -- -- end x; -- This expansion routine converts it into a procedure and sets the -- elaboration flag for the procedure to true, to represent the fact -- that the task body is now elaborated: -- procedure tnameB (_Task : access tnameV) is -- discriminal : dtype renames _Task.discriminant; -- procedure _clean is -- begin -- Abort_Defer.all; -- Complete_Task; -- Abort_Undefer.all; -- return; -- end _clean; -- begin -- Abort_Undefer.all; -- -- System.Task_Stages.Complete_Activation; -- -- at end -- _clean; -- end tnameB; -- tnameE := True; -- In addition, if the task body is an activator, then a call to -- activate tasks is added at the start of the statements, before -- the call to Complete_Activation, and if in addition the task is -- a master then it must be established as a master. These calls are -- inserted and analyzed in Expand_Cleanup_Actions, when the -- Handled_Sequence_Of_Statements is expanded. -- There is one discriminal declaration line generated for each -- discriminant that is present to provide an easy reference point -- for discriminant references inside the body (see Exp_Ch2.Expand_Name). -- Note on relationship to GNARLI definition. In the GNARLI definition, -- task body procedures have a profile (Arg : System.Address). That is -- needed because GNARLI has to use the same access-to-subprogram type -- for all task types. We depend here on knowing that in GNAT, passing -- an address argument by value is identical to passing a record value -- by access (in either case a single pointer is passed), so even though -- this procedure has the wrong profile. In fact it's all OK, since the -- callings sequence is identical. procedure Expand_N_Task_Body (N : Node_Id) is Loc : constant Source_Ptr := Sloc (N); Ttyp : constant Entity_Id := Corresponding_Spec (N); Call : Node_Id; New_N : Node_Id; begin -- Here we start the expansion by generating discriminal declarations Add_Discriminal_Declarations (Declarations (N), Ttyp, Name_uTask, Loc); -- Add a call to Abort_Undefer at the very beginning of the task -- body since this body is called with abort still deferred. if Abort_Allowed then Call := Build_Runtime_Call (Loc, RE_Abort_Undefer); Insert_Before (First (Statements (Handled_Statement_Sequence (N))), Call); Analyze (Call); end if; -- The statement part has already been protected with an at_end and -- cleanup actions. The call to Complete_Activation must be placed -- at the head of the sequence of statements of that block. The -- declarations have been merged in this sequence of statements but -- the first real statement is accessible from the First_Real_Statement -- field (which was set for exactly this purpose). if Restricted_Profile then Call := Build_Runtime_Call (Loc, RE_Complete_Restricted_Activation); else Call := Build_Runtime_Call (Loc, RE_Complete_Activation); end if; Insert_Before (First_Real_Statement (Handled_Statement_Sequence (N)), Call); Analyze (Call); New_N := Make_Subprogram_Body (Loc, Specification => Build_Task_Proc_Specification (Ttyp), Declarations => Declarations (N), Handled_Statement_Sequence => Handled_Statement_Sequence (N)); -- If the task contains generic instantiations, cleanup actions -- are delayed until after instantiation. Transfer the activation -- chain to the subprogram, to insure that the activation call is -- properly generated. It the task body contains inner tasks, indicate -- that the subprogram is a task master. if Delay_Cleanups (Ttyp) then Set_Activation_Chain_Entity (New_N, Activation_Chain_Entity (N)); Set_Is_Task_Master (New_N, Is_Task_Master (N)); end if; Rewrite (N, New_N); Analyze (N); -- Set elaboration flag immediately after task body. If the body -- is a subunit, the flag is set in the declarative part that -- contains the stub. if Nkind (Parent (N)) /= N_Subunit then Insert_After (N, Make_Assignment_Statement (Loc, Name => Make_Identifier (Loc, New_External_Name (Chars (Ttyp), 'E')), Expression => New_Reference_To (Standard_True, Loc))); end if; end Expand_N_Task_Body; ------------------------------------ -- Expand_N_Task_Type_Declaration -- ------------------------------------ -- We have several things to do. First we must create a Boolean flag used -- to mark if the body is elaborated yet. This variable gets set to True -- when the body of the task is elaborated (we can't rely on the normal -- ABE mechanism for the task body, since we need to pass an access to -- this elaboration boolean to the runtime routines). -- taskE : aliased Boolean := False; -- Next a variable is declared to hold the task stack size (either -- the default : Unspecified_Size, or a value that is set by a pragma -- Storage_Size). If the value of the pragma Storage_Size is static, then -- the variable is initialized with this value: -- taskZ : Size_Type := Unspecified_Size; -- or -- taskZ : Size_Type := Size_Type (size_expression); -- Next we create a corresponding record type declaration used to represent -- values of this task. The general form of this type declaration is -- type taskV (discriminants) is record -- _Task_Id : Task_Id; -- entry_family : array (bounds) of Void; -- _Priority : Integer := priority_expression; -- _Size : Size_Type := Size_Type (size_expression); -- _Task_Info : Task_Info_Type := task_info_expression; -- end record; -- The discriminants are present only if the corresponding task type has -- discriminants, and they exactly mirror the task type discriminants. -- The Id field is always present. It contains the Task_Id value, as -- set by the call to Create_Task. Note that although the task is -- limited, the task value record type is not limited, so there is no -- problem in passing this field as an out parameter to Create_Task. -- One entry_family component is present for each entry family in the -- task definition. The bounds correspond to the bounds of the entry -- family (which may depend on discriminants). The element type is -- void, since we only need the bounds information for determining -- the entry index. Note that the use of an anonymous array would -- normally be illegal in this context, but this is a parser check, -- and the semantics is quite prepared to handle such a case. -- The _Size field is present only if a Storage_Size pragma appears in -- the task definition. The expression captures the argument that was -- present in the pragma, and is used to override the task stack size -- otherwise associated with the task type. -- The _Priority field is present only if a Priority or Interrupt_Priority -- pragma appears in the task definition. The expression captures the -- argument that was present in the pragma, and is used to provide -- the Size parameter to the call to Create_Task. -- The _Task_Info field is present only if a Task_Info pragma appears in -- the task definition. The expression captures the argument that was -- present in the pragma, and is used to provide the Task_Image parameter -- to the call to Create_Task. -- When a task is declared, an instance of the task value record is -- created. The elaboration of this declaration creates the correct -- bounds for the entry families, and also evaluates the size, priority, -- and task_Info expressions if needed. The initialization routine for -- the task type itself then calls Create_Task with appropriate -- parameters to initialize the value of the Task_Id field. -- Note: the address of this record is passed as the "Discriminants" -- parameter for Create_Task. Since Create_Task merely passes this onto -- the body procedure, it does not matter that it does not quite match -- the GNARLI model of what is being passed (the record contains more -- than just the discriminants, but the discriminants can be found from -- the record value). -- The Entity_Id for this created record type is placed in the -- Corresponding_Record_Type field of the associated task type entity. -- Next we create a procedure specification for the task body procedure: -- procedure taskB (_Task : access taskV); -- Note that this must come after the record type declaration, since -- the spec refers to this type. It turns out that the initialization -- procedure for the value type references the task body spec, but that's -- fine, since it won't be generated till the freeze point for the type, -- which is certainly after the task body spec declaration. -- Finally, we set the task index value field of the entry attribute in -- the case of a simple entry. procedure Expand_N_Task_Type_Declaration (N : Node_Id) is Loc : constant Source_Ptr := Sloc (N); Tasktyp : constant Entity_Id := Etype (Defining_Identifier (N)); Tasknm : constant Name_Id := Chars (Tasktyp); Taskdef : constant Node_Id := Task_Definition (N); Proc_Spec : Node_Id; Rec_Decl : Node_Id; Rec_Ent : Entity_Id; Cdecls : List_Id; Elab_Decl : Node_Id; Size_Decl : Node_Id; Body_Decl : Node_Id; Task_Size : Node_Id; Ent_Stack : Entity_Id; Decl_Stack : Node_Id; begin -- If already expanded, nothing to do if Present (Corresponding_Record_Type (Tasktyp)) then return; end if; -- Here we will do the expansion Rec_Decl := Build_Corresponding_Record (N, Tasktyp, Loc); Rec_Ent := Defining_Identifier (Rec_Decl); Cdecls := Component_Items (Component_List (Type_Definition (Rec_Decl))); Qualify_Entity_Names (N); -- First create the elaboration variable Elab_Decl := Make_Object_Declaration (Loc, Defining_Identifier => Make_Defining_Identifier (Sloc (Tasktyp), Chars => New_External_Name (Tasknm, 'E')), Aliased_Present => True, Object_Definition => New_Reference_To (Standard_Boolean, Loc), Expression => New_Reference_To (Standard_False, Loc)); Insert_After (N, Elab_Decl); -- Next create the declaration of the size variable (tasknmZ) Set_Storage_Size_Variable (Tasktyp, Make_Defining_Identifier (Sloc (Tasktyp), Chars => New_External_Name (Tasknm, 'Z'))); if Present (Taskdef) and then Has_Storage_Size_Pragma (Taskdef) and then Is_Static_Expression (Expression (First ( Pragma_Argument_Associations (Find_Task_Or_Protected_Pragma ( Taskdef, Name_Storage_Size))))) then Size_Decl := Make_Object_Declaration (Loc, Defining_Identifier => Storage_Size_Variable (Tasktyp), Object_Definition => New_Reference_To (RTE (RE_Size_Type), Loc), Expression => Convert_To (RTE (RE_Size_Type), Relocate_Node ( Expression (First ( Pragma_Argument_Associations ( Find_Task_Or_Protected_Pragma (Taskdef, Name_Storage_Size))))))); else Size_Decl := Make_Object_Declaration (Loc, Defining_Identifier => Storage_Size_Variable (Tasktyp), Object_Definition => New_Reference_To (RTE (RE_Size_Type), Loc), Expression => New_Reference_To (RTE (RE_Unspecified_Size), Loc)); end if; Insert_After (Elab_Decl, Size_Decl); -- Next build the rest of the corresponding record declaration. -- This is done last, since the corresponding record initialization -- procedure will reference the previously created entities. -- Fill in the component declarations -- first the _Task_Id field Append_To (Cdecls, Make_Component_Declaration (Loc, Defining_Identifier => Make_Defining_Identifier (Loc, Name_uTask_Id), Component_Definition => Make_Component_Definition (Loc, Aliased_Present => False, Subtype_Indication => New_Reference_To (RTE (RO_ST_Task_Id), Loc)))); -- Declare static ATCB (that is, created by the expander) if we -- are using the Restricted run time. if Restricted_Profile then Append_To (Cdecls, Make_Component_Declaration (Loc, Defining_Identifier => Make_Defining_Identifier (Loc, Name_uATCB), Component_Definition => Make_Component_Definition (Loc, Aliased_Present => True, Subtype_Indication => Make_Subtype_Indication (Loc, Subtype_Mark => New_Occurrence_Of (RTE (RE_Ada_Task_Control_Block), Loc), Constraint => Make_Index_Or_Discriminant_Constraint (Loc, Constraints => New_List (Make_Integer_Literal (Loc, 0))))))); end if; -- Declare static stack (that is, created by the expander) if we -- are using the Restricted run time on a bare board configuration. if Restricted_Profile and then Preallocated_Stacks_On_Target then -- First we need to extract the appropriate stack size Ent_Stack := Make_Defining_Identifier (Loc, Name_uStack); if Present (Taskdef) and then Has_Storage_Size_Pragma (Taskdef) then Task_Size := Relocate_Node ( Expression (First ( Pragma_Argument_Associations ( Find_Task_Or_Protected_Pragma (Taskdef, Name_Storage_Size))))); else Task_Size := New_Reference_To (RTE (RE_Default_Stack_Size), Loc); end if; Decl_Stack := Make_Component_Declaration (Loc, Defining_Identifier => Ent_Stack, Component_Definition => Make_Component_Definition (Loc, Aliased_Present => True, Subtype_Indication => 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 => Convert_To (RTE (RE_Storage_Offset), Task_Size))))))); Append_To (Cdecls, Decl_Stack); -- The appropriate alignment for the stack is ensured by the -- run-time code in charge of task creation. end if; -- Add components for entry families Collect_Entry_Families (Loc, Cdecls, Size_Decl, Tasktyp); -- Add the _Priority component if a Priority pragma is present if Present (Taskdef) and then Has_Priority_Pragma (Taskdef) then declare Prag : constant Node_Id := Find_Task_Or_Protected_Pragma (Taskdef, Name_Priority); Expr : Node_Id; begin Expr := First (Pragma_Argument_Associations (Prag)); if Nkind (Expr) = N_Pragma_Argument_Association then Expr := Expression (Expr); end if; Expr := New_Copy_Tree (Expr); -- Add conversion to proper type to do range check if required -- Note that for runtime units, we allow out of range interrupt -- priority values to be used in a priority pragma. This is for -- the benefit of some versions of System.Interrupts which use -- a special server task with maximum interrupt priority. if Chars (Prag) = Name_Priority and then not GNAT_Mode then Rewrite (Expr, Convert_To (RTE (RE_Priority), Expr)); else Rewrite (Expr, Convert_To (RTE (RE_Any_Priority), Expr)); end if; Append_To (Cdecls, Make_Component_Declaration (Loc, Defining_Identifier => Make_Defining_Identifier (Loc, Name_uPriority), Component_Definition => Make_Component_Definition (Loc, Aliased_Present => False, Subtype_Indication => New_Reference_To (Standard_Integer, Loc)), Expression => Expr)); end; end if; -- Add the _Task_Size component if a Storage_Size pragma is present if Present (Taskdef) and then Has_Storage_Size_Pragma (Taskdef) then Append_To (Cdecls, Make_Component_Declaration (Loc, Defining_Identifier => Make_Defining_Identifier (Loc, Name_uSize), Component_Definition => Make_Component_Definition (Loc, Aliased_Present => False, Subtype_Indication => New_Reference_To (RTE (RE_Size_Type), Loc)), Expression => Convert_To (RTE (RE_Size_Type), Relocate_Node ( Expression (First ( Pragma_Argument_Associations ( Find_Task_Or_Protected_Pragma (Taskdef, Name_Storage_Size)))))))); end if; -- Add the _Task_Info component if a Task_Info pragma is present if Present (Taskdef) and then Has_Task_Info_Pragma (Taskdef) then Append_To (Cdecls, Make_Component_Declaration (Loc, Defining_Identifier => Make_Defining_Identifier (Loc, Name_uTask_Info), Component_Definition => Make_Component_Definition (Loc, Aliased_Present => False, Subtype_Indication => New_Reference_To (RTE (RE_Task_Info_Type), Loc)), Expression => New_Copy ( Expression (First ( Pragma_Argument_Associations ( Find_Task_Or_Protected_Pragma (Taskdef, Name_Task_Info))))))); end if; Insert_After (Size_Decl, Rec_Decl); -- Analyze the record declaration immediately after construction, -- because the initialization procedure is needed for single task -- declarations before the next entity is analyzed. Analyze (Rec_Decl); -- Create the declaration of the task body procedure Proc_Spec := Build_Task_Proc_Specification (Tasktyp); Body_Decl := Make_Subprogram_Declaration (Loc, Specification => Proc_Spec); Insert_After (Rec_Decl, Body_Decl); -- The subprogram does not comes from source, so we have to indicate -- the need for debugging information explicitly. Set_Needs_Debug_Info (Defining_Entity (Proc_Spec), Comes_From_Source (Original_Node (N))); -- Now we can freeze the corresponding record. This needs manually -- freezing, since it is really part of the task type, and the task -- type is frozen at this stage. We of course need the initialization -- procedure for this corresponding record type and we won't get it -- in time if we don't freeze now. declare L : constant List_Id := Freeze_Entity (Rec_Ent, Loc); begin if Is_Non_Empty_List (L) then Insert_List_After (Body_Decl, L); end if; end; -- Complete the expansion of access types to the current task -- type, if any were declared. Expand_Previous_Access_Type (Tasktyp); end Expand_N_Task_Type_Declaration; ------------------------------- -- Expand_N_Timed_Entry_Call -- ------------------------------- -- A timed entry call in normal case is not implemented using ATC -- mechanism anymore for efficiency reason. -- select -- T.E; -- S1; -- or -- Delay D; -- S2; -- end select; -- is expanded as follow: -- 1) When T.E is a task entry_call; -- declare -- B : Boolean; -- X : Task_Entry_Index := ; -- DX : Duration := To_Duration (D); -- M : Delay_Mode := ; -- P : parms := (parm, parm, parm); -- begin -- Timed_Protected_Entry_Call (, X, P'Address, -- DX, M, B); -- if B then -- S1; -- else -- S2; -- end if; -- end; -- 2) When T.E is a protected entry_call; -- declare -- B : Boolean; -- X : Protected_Entry_Index := ; -- DX : Duration := To_Duration (D); -- M : Delay_Mode := ; -- P : parms := (parm, parm, parm); -- begin -- Timed_Protected_Entry_Call ('unchecked_access, X, -- P'Address, DX, M, B); -- if B then -- S1; -- else -- S2; -- end if; -- end; procedure Expand_N_Timed_Entry_Call (N : Node_Id) is Loc : constant Source_Ptr := Sloc (N); E_Call : Node_Id := Entry_Call_Statement (Entry_Call_Alternative (N)); E_Stats : constant List_Id := Statements (Entry_Call_Alternative (N)); D_Stat : constant Node_Id := Delay_Statement (Delay_Alternative (N)); D_Stats : constant List_Id := Statements (Delay_Alternative (N)); Stmts : List_Id; Stmt : Node_Id; Parms : List_Id; Parm : Node_Id; Concval : Node_Id; Ename : Node_Id; Index : Node_Id; Decls : List_Id; Disc : Node_Id; Conv : Node_Id; B : Entity_Id; D : Entity_Id; Dtyp : Entity_Id; M : Entity_Id; Call : Node_Id; Dummy : Node_Id; begin -- The arguments in the call may require dynamic allocation, and the -- call statement may have been transformed into a block. The block -- may contain additional declarations for internal entities, and the -- original call is found by sequential search. if Nkind (E_Call) = N_Block_Statement then E_Call := First (Statements (Handled_Statement_Sequence (E_Call))); while Nkind (E_Call) /= N_Procedure_Call_Statement and then Nkind (E_Call) /= N_Entry_Call_Statement loop Next (E_Call); end loop; end if; -- Build an entry call using Simple_Entry_Call. We will use this as the -- base for creating appropriate calls. Extract_Entry (E_Call, Concval, Ename, Index); Build_Simple_Entry_Call (E_Call, Concval, Ename, Index); Stmts := Statements (Handled_Statement_Sequence (E_Call)); Decls := Declarations (E_Call); if No (Decls) then Decls := New_List; end if; Dtyp := Base_Type (Etype (Expression (D_Stat))); -- Use the type of the delay expression (Calendar or Real_Time) -- to generate the appropriate conversion. if Nkind (D_Stat) = N_Delay_Relative_Statement then Disc := Make_Integer_Literal (Loc, 0); Conv := Relocate_Node (Expression (D_Stat)); elsif Is_RTE (Dtyp, RO_CA_Time) then Disc := Make_Integer_Literal (Loc, 1); Conv := Make_Function_Call (Loc, New_Reference_To (RTE (RO_CA_To_Duration), Loc), New_List (New_Copy (Expression (D_Stat)))); else pragma Assert (Is_RTE (Dtyp, RO_RT_Time)); Disc := Make_Integer_Literal (Loc, 2); Conv := Make_Function_Call (Loc, New_Reference_To (RTE (RO_RT_To_Duration), Loc), New_List (New_Copy (Expression (D_Stat)))); end if; -- Create Duration and Delay_Mode objects for passing a delay value D := Make_Defining_Identifier (Loc, New_Internal_Name ('D')); M := Make_Defining_Identifier (Loc, New_Internal_Name ('M')); Append_To (Decls, Make_Object_Declaration (Loc, Defining_Identifier => D, Object_Definition => New_Reference_To (Standard_Duration, Loc))); Append_To (Decls, Make_Object_Declaration (Loc, Defining_Identifier => M, Object_Definition => New_Reference_To (Standard_Integer, Loc), Expression => Disc)); B := Make_Defining_Identifier (Loc, Name_uB); -- Create a boolean object used for a return parameter Prepend_To (Decls, Make_Object_Declaration (Loc, Defining_Identifier => B, Object_Definition => New_Reference_To (Standard_Boolean, Loc))); Stmt := First (Stmts); -- Skip assignments to temporaries created for in-out parameters. -- This makes unwarranted assumptions about the shape of the expanded -- tree for the call, and should be cleaned up ??? while Nkind (Stmt) /= N_Procedure_Call_Statement loop Next (Stmt); end loop; -- Do the assignement at this stage only because the evaluation of the -- expression must not occur before (see ACVC C97302A). Insert_Before (Stmt, Make_Assignment_Statement (Loc, Name => New_Reference_To (D, Loc), Expression => Conv)); Call := Stmt; Parms := Parameter_Associations (Call); -- For a protected type, we build a Timed_Protected_Entry_Call if Is_Protected_Type (Etype (Concval)) then -- Create a new call statement Parm := First (Parms); while Present (Parm) and then not Is_RTE (Etype (Parm), RE_Call_Modes) loop Next (Parm); end loop; Dummy := Remove_Next (Next (Parm)); -- Remove garbage is following the Cancel_Param if present Dummy := Next (Parm); -- Remove the mode of the Protected_Entry_Call call, then remove the -- Communication_Block of the Protected_Entry_Call call, and finally -- add Duration and a Delay_Mode parameter pragma Assert (Present (Parm)); Rewrite (Parm, New_Reference_To (D, Loc)); Rewrite (Dummy, New_Reference_To (M, Loc)); -- Add a Boolean flag for successful entry call Append_To (Parms, New_Reference_To (B, Loc)); if Abort_Allowed or else Restriction_Active (No_Entry_Queue) = False or else Number_Entries (Etype (Concval)) > 1 then Rewrite (Call, Make_Procedure_Call_Statement (Loc, Name => New_Reference_To (RTE (RE_Timed_Protected_Entry_Call), Loc), Parameter_Associations => Parms)); else Parm := First (Parms); while Present (Parm) and then not Is_RTE (Etype (Parm), RE_Protected_Entry_Index) loop Next (Parm); end loop; Remove (Parm); Rewrite (Call, Make_Procedure_Call_Statement (Loc, Name => New_Reference_To ( RTE (RE_Timed_Protected_Single_Entry_Call), Loc), Parameter_Associations => Parms)); end if; -- For the task case, build a Timed_Task_Entry_Call else -- Create a new call statement Append_To (Parms, New_Reference_To (D, Loc)); Append_To (Parms, New_Reference_To (M, Loc)); Append_To (Parms, New_Reference_To (B, Loc)); Rewrite (Call, Make_Procedure_Call_Statement (Loc, Name => New_Reference_To (RTE (RE_Timed_Task_Entry_Call), Loc), Parameter_Associations => Parms)); end if; Append_To (Stmts, Make_Implicit_If_Statement (N, Condition => New_Reference_To (B, Loc), Then_Statements => E_Stats, Else_Statements => D_Stats)); Rewrite (N, Make_Block_Statement (Loc, Declarations => Decls, Handled_Statement_Sequence => Make_Handled_Sequence_Of_Statements (Loc, Stmts))); Analyze (N); end Expand_N_Timed_Entry_Call; ---------------------------------------- -- Expand_Protected_Body_Declarations -- ---------------------------------------- -- Part of the expansion of a protected body involves the creation of -- a declaration that can be referenced from the statement sequences of -- the entry bodies: -- A : Address; -- This declaration is inserted in the declarations of the service -- entries procedure for the protected body, and it is important that -- it be inserted before the statements of the entry body statement -- sequences are analyzed. Thus it would be too late to create this -- declaration in the Expand_N_Protected_Body routine, which is why -- there is a separate procedure to be called directly from Sem_Ch9. -- Ann is used to hold the address of the record containing the parameters -- (see Expand_N_Entry_Call for more details on how this record is built). -- References to the parameters do an unchecked conversion of this address -- to a pointer to the required record type, and then access the field that -- holds the value of the required parameter. The entity for the address -- variable is held as the top stack element (i.e. the last element) of the -- Accept_Address stack in the corresponding entry entity, and this element -- must be set in place before the statements are processed. -- No stack is needed for entry bodies, since they cannot be nested, but -- it is kept for consistency between protected and task entries. The -- stack will never contain more than one element. There is also only one -- such variable for a given protected body, but this is placed on the -- Accept_Address stack of all of the entries, again for consistency. -- To expand the requeue statement, a label is provided at the end of -- the loop in the entry service routine created by the expander (see -- Expand_N_Protected_Body for details), so that the statement can be -- skipped after the requeue is complete. This label is created during the -- expansion of the entry body, which will take place after the expansion -- of the requeue statements that it contains, so a placeholder defining -- identifier is associated with the task type here. -- Another label is provided following case statement created by the -- expander. This label is need for implementing return statement from -- entry body so that a return can be expanded as a goto to this label. -- This label is created during the expansion of the entry body, which -- will take place after the expansion of the return statements that it -- contains. Therefore, just like the label for expanding requeues, we -- need another placeholder for the label. procedure Expand_Protected_Body_Declarations (N : Node_Id; Spec_Id : Entity_Id) is Op : Node_Id; begin if No_Run_Time_Mode then Error_Msg_CRT ("protected body", N); return; elsif Expander_Active then -- Associate privals with the first subprogram or entry -- body to be expanded. These are used to expand references -- to private data objects. Op := First_Protected_Operation (Declarations (N)); if Present (Op) then Set_Discriminals (Parent (Spec_Id)); Set_Privals (Parent (Spec_Id), Op, Sloc (N)); end if; end if; end Expand_Protected_Body_Declarations; ------------------------- -- External_Subprogram -- ------------------------- function External_Subprogram (E : Entity_Id) return Entity_Id is Subp : constant Entity_Id := Protected_Body_Subprogram (E); Decl : constant Node_Id := Unit_Declaration_Node (E); begin -- If the protected operation is defined in the visible part of the -- protected type, or if it is an interrupt handler, the internal and -- external subprograms follow each other on the entity chain. If the -- operation is defined in the private part of the type, there is no -- need for a separate locking version of the operation, and internal -- calls use the protected_body_subprogram directly. if List_Containing (Decl) = Visible_Declarations (Parent (Decl)) or else Is_Interrupt_Handler (E) then return Next_Entity (Subp); else return (Subp); end if; end External_Subprogram; ------------------- -- Extract_Entry -- ------------------- procedure Extract_Entry (N : Node_Id; Concval : out Node_Id; Ename : out Node_Id; Index : out Node_Id) is Nam : constant Node_Id := Name (N); begin -- For a simple entry, the name is a selected component, with the -- prefix being the task value, and the selector being the entry. if Nkind (Nam) = N_Selected_Component then Concval := Prefix (Nam); Ename := Selector_Name (Nam); Index := Empty; -- For a member of an entry family, the name is an indexed -- component where the prefix is a selected component, -- whose prefix in turn is the task value, and whose -- selector is the entry family. The single expression in -- the expressions list of the indexed component is the -- subscript for the family. else pragma Assert (Nkind (Nam) = N_Indexed_Component); Concval := Prefix (Prefix (Nam)); Ename := Selector_Name (Prefix (Nam)); Index := First (Expressions (Nam)); end if; end Extract_Entry; ------------------- -- Family_Offset -- ------------------- function Family_Offset (Loc : Source_Ptr; Hi : Node_Id; Lo : Node_Id; Ttyp : Entity_Id) return Node_Id is function Convert_Discriminant_Ref (Bound : Node_Id) return Node_Id; -- If one of the bounds is a reference to a discriminant, replace -- with corresponding discriminal of type. Within the body of a task -- retrieve the renamed discriminant by simple visibility, using its -- generated name. Within a protected object, find the original dis- -- criminant and replace it with the discriminal of the current prot- -- ected operation. ------------------------------ -- Convert_Discriminant_Ref -- ------------------------------ function Convert_Discriminant_Ref (Bound : Node_Id) return Node_Id is Loc : constant Source_Ptr := Sloc (Bound); B : Node_Id; D : Entity_Id; begin if Is_Entity_Name (Bound) and then Ekind (Entity (Bound)) = E_Discriminant then if Is_Task_Type (Ttyp) and then Has_Completion (Ttyp) then B := Make_Identifier (Loc, Chars (Entity (Bound))); Find_Direct_Name (B); elsif Is_Protected_Type (Ttyp) then D := First_Discriminant (Ttyp); while Chars (D) /= Chars (Entity (Bound)) loop Next_Discriminant (D); end loop; B := New_Reference_To (Discriminal (D), Loc); else B := New_Reference_To (Discriminal (Entity (Bound)), Loc); end if; elsif Nkind (Bound) = N_Attribute_Reference then return Bound; else B := New_Copy_Tree (Bound); end if; return Make_Attribute_Reference (Loc, Attribute_Name => Name_Pos, Prefix => New_Occurrence_Of (Etype (Bound), Loc), Expressions => New_List (B)); end Convert_Discriminant_Ref; -- Start of processing for Family_Offset begin return Make_Op_Subtract (Loc, Left_Opnd => Convert_Discriminant_Ref (Hi), Right_Opnd => Convert_Discriminant_Ref (Lo)); end Family_Offset; ----------------- -- Family_Size -- ----------------- function Family_Size (Loc : Source_Ptr; Hi : Node_Id; Lo : Node_Id; Ttyp : Entity_Id) return Node_Id is Ityp : Entity_Id; begin if Is_Task_Type (Ttyp) then Ityp := RTE (RE_Task_Entry_Index); else Ityp := RTE (RE_Protected_Entry_Index); end if; return Make_Attribute_Reference (Loc, Prefix => New_Reference_To (Ityp, Loc), Attribute_Name => Name_Max, Expressions => New_List ( Make_Op_Add (Loc, Left_Opnd => Family_Offset (Loc, Hi, Lo, Ttyp), Right_Opnd => Make_Integer_Literal (Loc, 1)), Make_Integer_Literal (Loc, 0))); end Family_Size; ----------------------------------- -- Find_Task_Or_Protected_Pragma -- ----------------------------------- function Find_Task_Or_Protected_Pragma (T : Node_Id; P : Name_Id) return Node_Id is N : Node_Id; begin N := First (Visible_Declarations (T)); while Present (N) loop if Nkind (N) = N_Pragma then if Chars (N) = P then return N; elsif P = Name_Priority and then Chars (N) = Name_Interrupt_Priority then return N; else Next (N); end if; else Next (N); end if; end loop; N := First (Private_Declarations (T)); while Present (N) loop if Nkind (N) = N_Pragma then if Chars (N) = P then return N; elsif P = Name_Priority and then Chars (N) = Name_Interrupt_Priority then return N; else Next (N); end if; else Next (N); end if; end loop; raise Program_Error; end Find_Task_Or_Protected_Pragma; ------------------------------- -- First_Protected_Operation -- ------------------------------- function First_Protected_Operation (D : List_Id) return Node_Id is First_Op : Node_Id; begin First_Op := First (D); while Present (First_Op) and then Nkind (First_Op) /= N_Subprogram_Body and then Nkind (First_Op) /= N_Entry_Body loop Next (First_Op); end loop; return First_Op; end First_Protected_Operation; -------------------------------- -- Index_Constant_Declaration -- -------------------------------- function Index_Constant_Declaration (N : Node_Id; Index_Id : Entity_Id; Prot : Entity_Id) return List_Id is Loc : constant Source_Ptr := Sloc (N); Decls : constant List_Id := New_List; Index_Con : constant Entity_Id := Entry_Index_Constant (Index_Id); Index_Typ : Entity_Id; Hi : Node_Id := Type_High_Bound (Etype (Index_Id)); Lo : Node_Id := Type_Low_Bound (Etype (Index_Id)); function Replace_Discriminant (Bound : Node_Id) return Node_Id; -- The bounds of the entry index may depend on discriminants, so -- each declaration of an entry_index_constant must have its own -- subtype declaration, using the local renaming of the object discri- -- minant. -------------------------- -- Replace_Discriminant -- -------------------------- function Replace_Discriminant (Bound : Node_Id) return Node_Id is begin if Nkind (Bound) = N_Identifier and then Ekind (Entity (Bound)) = E_Constant and then Present (Discriminal_Link (Entity (Bound))) then return Make_Identifier (Loc, Chars (Entity (Bound))); else return Duplicate_Subexpr (Bound); end if; end Replace_Discriminant; -- Start of processing for Index_Constant_Declaration begin Set_Discriminal_Link (Index_Con, Index_Id); if Is_Entity_Name ( Original_Node (Discrete_Subtype_Definition (Parent (Index_Id)))) then -- Simple case: entry family is given by a subtype mark, and index -- constant has the same type, no replacement needed. Index_Typ := Etype (Index_Id); else Hi := Replace_Discriminant (Hi); Lo := Replace_Discriminant (Lo); Index_Typ := Make_Defining_Identifier (Loc, New_Internal_Name ('J')); Append ( Make_Subtype_Declaration (Loc, Defining_Identifier => Index_Typ, Subtype_Indication => Make_Subtype_Indication (Loc, Subtype_Mark => New_Occurrence_Of (Base_Type (Etype (Index_Id)), Loc), Constraint => Make_Range_Constraint (Loc, Range_Expression => Make_Range (Loc, Lo, Hi)))), Decls); end if; Append ( Make_Object_Declaration (Loc, Defining_Identifier => Index_Con, Constant_Present => True, Object_Definition => New_Occurrence_Of (Index_Typ, Loc), Expression => Make_Attribute_Reference (Loc, Prefix => New_Reference_To (Index_Typ, Loc), Attribute_Name => Name_Val, Expressions => New_List ( Make_Op_Add (Loc, Left_Opnd => Make_Op_Subtract (Loc, Left_Opnd => Make_Identifier (Loc, Name_uE), Right_Opnd => Entry_Index_Expression (Loc, Defining_Identifier (N), Empty, Prot)), Right_Opnd => Make_Attribute_Reference (Loc, Prefix => New_Reference_To (Index_Typ, Loc), Attribute_Name => Name_Pos, Expressions => New_List ( Make_Attribute_Reference (Loc, Prefix => New_Reference_To (Index_Typ, Loc), Attribute_Name => Name_First))))))), Decls); return Decls; end Index_Constant_Declaration; -------------------------------- -- Make_Initialize_Protection -- -------------------------------- function Make_Initialize_Protection (Protect_Rec : Entity_Id) return List_Id is Loc : constant Source_Ptr := Sloc (Protect_Rec); P_Arr : Entity_Id; Pdef : Node_Id; Pdec : Node_Id; Ptyp : constant Node_Id := Corresponding_Concurrent_Type (Protect_Rec); Args : List_Id; L : constant List_Id := New_List; Has_Entry : constant Boolean := Has_Entries (Ptyp); Restricted : constant Boolean := Restricted_Profile; begin -- We may need two calls to properly initialize the object, one -- to Initialize_Protection, and possibly one to Install_Handlers -- if we have a pragma Attach_Handler. -- Get protected declaration. In the case of a task type declaration, -- this is simply the parent of the protected type entity. -- In the single protected object -- declaration, this parent will be the implicit type, and we can find -- the corresponding single protected object declaration by -- searching forward in the declaration list in the tree. -- ??? I am not sure that the test for N_Single_Protected_Declaration -- is needed here. Nodes of this type should have been removed -- during semantic analysis. Pdec := Parent (Ptyp); while Nkind (Pdec) /= N_Protected_Type_Declaration and then Nkind (Pdec) /= N_Single_Protected_Declaration loop Next (Pdec); end loop; -- Now we can find the object definition from this declaration Pdef := Protected_Definition (Pdec); -- Build the parameter list for the call. Note that _Init is the name -- of the formal for the object to be initialized, which is the task -- value record itself. Args := New_List; -- Object parameter. This is a pointer to the object of type -- Protection used by the GNARL to control the protected object. Append_To (Args, Make_Attribute_Reference (Loc, Prefix => Make_Selected_Component (Loc, Prefix => Make_Identifier (Loc, Name_uInit), Selector_Name => Make_Identifier (Loc, Name_uObject)), Attribute_Name => Name_Unchecked_Access)); -- Priority parameter. Set to Unspecified_Priority unless there is a -- priority pragma, in which case we take the value from the pragma, -- or there is an interrupt pragma and no priority pragma, and we -- set the ceiling to Interrupt_Priority'Last, an implementation- -- defined value, see D.3(10). if Present (Pdef) and then Has_Priority_Pragma (Pdef) then Append_To (Args, Duplicate_Subexpr_No_Checks (Expression (First (Pragma_Argument_Associations (Find_Task_Or_Protected_Pragma (Pdef, Name_Priority)))))); elsif Has_Interrupt_Handler (Ptyp) or else Has_Attach_Handler (Ptyp) then -- When no priority is specified but an xx_Handler pragma is, -- we default to System.Interrupts.Default_Interrupt_Priority, -- see D.3(10). Append_To (Args, New_Reference_To (RTE (RE_Default_Interrupt_Priority), Loc)); else Append_To (Args, New_Reference_To (RTE (RE_Unspecified_Priority), Loc)); end if; if Has_Entry or else Has_Interrupt_Handler (Ptyp) or else Has_Attach_Handler (Ptyp) then -- Compiler_Info parameter. This parameter allows entry body -- procedures and barrier functions to be called from the runtime. -- It is a pointer to the record generated by the compiler to -- represent the protected object. if Has_Entry or else not Restricted then Append_To (Args, Make_Attribute_Reference (Loc, Prefix => Make_Identifier (Loc, Name_uInit), Attribute_Name => Name_Address)); end if; if Has_Entry then -- Entry_Bodies parameter. This is a pointer to an array of -- pointers to the entry body procedures and barrier functions -- of the object. If the protected type has no entries this -- object will not exist; in this case, pass a null. P_Arr := Entry_Bodies_Array (Ptyp); Append_To (Args, Make_Attribute_Reference (Loc, Prefix => New_Reference_To (P_Arr, Loc), Attribute_Name => Name_Unrestricted_Access)); if Abort_Allowed or else Restriction_Active (No_Entry_Queue) = False or else Number_Entries (Ptyp) > 1 then -- Find index mapping function (clumsy but ok for now) while Ekind (P_Arr) /= E_Function loop Next_Entity (P_Arr); end loop; Append_To (Args, Make_Attribute_Reference (Loc, Prefix => New_Reference_To (P_Arr, Loc), Attribute_Name => Name_Unrestricted_Access)); end if; elsif not Restricted then Append_To (Args, Make_Null (Loc)); Append_To (Args, Make_Null (Loc)); end if; if Abort_Allowed or else Restriction_Active (No_Entry_Queue) = False or else Number_Entries (Ptyp) > 1 then Append_To (L, Make_Procedure_Call_Statement (Loc, Name => New_Reference_To ( RTE (RE_Initialize_Protection_Entries), Loc), Parameter_Associations => Args)); elsif not Has_Entry and then Restricted then Append_To (L, Make_Procedure_Call_Statement (Loc, Name => New_Reference_To ( RTE (RE_Initialize_Protection), Loc), Parameter_Associations => Args)); else Append_To (L, Make_Procedure_Call_Statement (Loc, Name => New_Reference_To ( RTE (RE_Initialize_Protection_Entry), Loc), Parameter_Associations => Args)); end if; else Append_To (L, Make_Procedure_Call_Statement (Loc, Name => New_Reference_To (RTE (RE_Initialize_Protection), Loc), Parameter_Associations => Args)); end if; if Has_Attach_Handler (Ptyp) then -- We have a list of N Attach_Handler (ProcI, ExprI), -- and we have to make the following call: -- Install_Handlers (_object, -- ((Expr1, Proc1'access), ...., (ExprN, ProcN'access)); -- or, in the case of Ravenscar: -- Install_Handlers -- ((Expr1, Proc1'access), ...., (ExprN, ProcN'access)); declare Args : constant List_Id := New_List; Table : constant List_Id := New_List; Ritem : Node_Id := First_Rep_Item (Ptyp); begin if not Restricted then -- Appends the _object argument Append_To (Args, Make_Attribute_Reference (Loc, Prefix => Make_Selected_Component (Loc, Prefix => Make_Identifier (Loc, Name_uInit), Selector_Name => Make_Identifier (Loc, Name_uObject)), Attribute_Name => Name_Unchecked_Access)); end if; -- Build the Attach_Handler table argument while Present (Ritem) loop if Nkind (Ritem) = N_Pragma and then Chars (Ritem) = Name_Attach_Handler then declare Handler : constant Node_Id := First (Pragma_Argument_Associations (Ritem)); Interrupt : constant Node_Id := Next (Handler); Expr : constant Node_Id := Expression (Interrupt); begin Append_To (Table, Make_Aggregate (Loc, Expressions => New_List ( Unchecked_Convert_To (RTE (RE_System_Interrupt_Id), Expr), Make_Attribute_Reference (Loc, Prefix => Make_Selected_Component (Loc, Make_Identifier (Loc, Name_uInit), Duplicate_Subexpr_No_Checks (Expression (Handler))), Attribute_Name => Name_Access)))); end; end if; Next_Rep_Item (Ritem); end loop; -- Append the table argument we just built Append_To (Args, Make_Aggregate (Loc, Table)); -- Append the Install_Handler call to the statements Append_To (L, Make_Procedure_Call_Statement (Loc, Name => New_Reference_To (RTE (RE_Install_Handlers), Loc), Parameter_Associations => Args)); end; end if; return L; end Make_Initialize_Protection; --------------------------- -- Make_Task_Create_Call -- --------------------------- function Make_Task_Create_Call (Task_Rec : Entity_Id) return Node_Id is Loc : constant Source_Ptr := Sloc (Task_Rec); Name : Node_Id; Tdef : Node_Id; Tdec : Node_Id; Ttyp : Node_Id; Tnam : Name_Id; Args : List_Id; Ecount : Node_Id; begin Ttyp := Corresponding_Concurrent_Type (Task_Rec); Tnam := Chars (Ttyp); -- Get task declaration. In the case of a task type declaration, this -- is simply the parent of the task type entity. In the single task -- declaration, this parent will be the implicit type, and we can find -- the corresponding single task declaration by searching forward in -- the declaration list in the tree. -- ??? I am not sure that the test for N_Single_Task_Declaration -- is needed here. Nodes of this type should have been removed -- during semantic analysis. Tdec := Parent (Ttyp); while Nkind (Tdec) /= N_Task_Type_Declaration and then Nkind (Tdec) /= N_Single_Task_Declaration loop Next (Tdec); end loop; -- Now we can find the task definition from this declaration Tdef := Task_Definition (Tdec); -- Build the parameter list for the call. Note that _Init is the name -- of the formal for the object to be initialized, which is the task -- value record itself. Args := New_List; -- Priority parameter. Set to Unspecified_Priority unless there is a -- priority pragma, in which case we take the value from the pragma. if Present (Tdef) and then Has_Priority_Pragma (Tdef) then Append_To (Args, Make_Selected_Component (Loc, Prefix => Make_Identifier (Loc, Name_uInit), Selector_Name => Make_Identifier (Loc, Name_uPriority))); else Append_To (Args, New_Reference_To (RTE (RE_Unspecified_Priority), Loc)); end if; -- Optional Stack parameter if Restricted_Profile then -- If the stack has been preallocated by the expander then -- pass its address. Otherwise, pass a null address. if Preallocated_Stacks_On_Target then Append_To (Args, Make_Attribute_Reference (Loc, Prefix => Make_Selected_Component (Loc, Prefix => Make_Identifier (Loc, Name_uInit), Selector_Name => Make_Identifier (Loc, Name_uStack)), Attribute_Name => Name_Address)); else Append_To (Args, New_Reference_To (RTE (RE_Null_Address), Loc)); end if; end if; -- Size parameter. If no Storage_Size pragma is present, then -- the size is taken from the taskZ variable for the type, which -- is either Unspecified_Size, or has been reset by the use of -- a Storage_Size attribute definition clause. If a pragma is -- present, then the size is taken from the _Size field of the -- task value record, which was set from the pragma value. if Present (Tdef) and then Has_Storage_Size_Pragma (Tdef) then Append_To (Args, Make_Selected_Component (Loc, Prefix => Make_Identifier (Loc, Name_uInit), Selector_Name => Make_Identifier (Loc, Name_uSize))); else Append_To (Args, New_Reference_To (Storage_Size_Variable (Ttyp), Loc)); end if; -- Task_Info parameter. Set to Unspecified_Task_Info unless there is a -- Task_Info pragma, in which case we take the value from the pragma. if Present (Tdef) and then Has_Task_Info_Pragma (Tdef) then Append_To (Args, Make_Selected_Component (Loc, Prefix => Make_Identifier (Loc, Name_uInit), Selector_Name => Make_Identifier (Loc, Name_uTask_Info))); else Append_To (Args, New_Reference_To (RTE (RE_Unspecified_Task_Info), Loc)); end if; if not Restricted_Profile then -- Number of entries. This is an expression of the form: -- -- n + _Init.a'Length + _Init.a'B'Length + ... -- -- where a,b... are the entry family names for the task definition Ecount := Build_Entry_Count_Expression ( Ttyp, Component_Items (Component_List ( Type_Definition (Parent ( Corresponding_Record_Type (Ttyp))))), Loc); Append_To (Args, Ecount); -- Master parameter. This is a reference to the _Master parameter of -- the initialization procedure, except in the case of the pragma -- Restrictions (No_Task_Hierarchy) where the value is fixed to 3. -- See comments in System.Tasking.Initialization.Init_RTS for the -- value 3. if Restriction_Active (No_Task_Hierarchy) = False then Append_To (Args, Make_Identifier (Loc, Name_uMaster)); else Append_To (Args, Make_Integer_Literal (Loc, 3)); end if; end if; -- State parameter. This is a pointer to the task body procedure. The -- required value is obtained by taking the address of the task body -- procedure and converting it (with an unchecked conversion) to the -- type required by the task kernel. For further details, see the -- description of Expand_Task_Body Append_To (Args, Unchecked_Convert_To (RTE (RE_Task_Procedure_Access), Make_Attribute_Reference (Loc, Prefix => New_Occurrence_Of (Get_Task_Body_Procedure (Ttyp), Loc), Attribute_Name => Name_Address))); -- Discriminants parameter. This is just the address of the task -- value record itself (which contains the discriminant values Append_To (Args, Make_Attribute_Reference (Loc, Prefix => Make_Identifier (Loc, Name_uInit), Attribute_Name => Name_Address)); -- Elaborated parameter. This is an access to the elaboration Boolean Append_To (Args, Make_Attribute_Reference (Loc, Prefix => Make_Identifier (Loc, New_External_Name (Tnam, 'E')), Attribute_Name => Name_Unchecked_Access)); -- Chain parameter. This is a reference to the _Chain parameter of -- the initialization procedure. Append_To (Args, Make_Identifier (Loc, Name_uChain)); -- Task name parameter. Take this from the _Task_Id parameter to the -- init call unless there is a Task_Name pragma, in which case we take -- the value from the pragma. if Present (Tdef) and then Has_Task_Name_Pragma (Tdef) then Append_To (Args, New_Copy ( Expression (First ( Pragma_Argument_Associations ( Find_Task_Or_Protected_Pragma (Tdef, Name_Task_Name)))))); else Append_To (Args, Make_Identifier (Loc, Name_uTask_Name)); end if; -- Created_Task parameter. This is the _Task_Id field of the task -- record value Append_To (Args, Make_Selected_Component (Loc, Prefix => Make_Identifier (Loc, Name_uInit), Selector_Name => Make_Identifier (Loc, Name_uTask_Id))); if Restricted_Profile then Name := New_Reference_To (RTE (RE_Create_Restricted_Task), Loc); else Name := New_Reference_To (RTE (RE_Create_Task), Loc); end if; return Make_Procedure_Call_Statement (Loc, Name => Name, Parameter_Associations => Args); end Make_Task_Create_Call; ------------------------------ -- Next_Protected_Operation -- ------------------------------ function Next_Protected_Operation (N : Node_Id) return Node_Id is Next_Op : Node_Id; begin Next_Op := Next (N); while Present (Next_Op) and then Nkind (Next_Op) /= N_Subprogram_Body and then Nkind (Next_Op) /= N_Entry_Body loop Next (Next_Op); end loop; return Next_Op; end Next_Protected_Operation; ---------------------- -- Set_Discriminals -- ---------------------- procedure Set_Discriminals (Dec : Node_Id) is D : Entity_Id; Pdef : Entity_Id; D_Minal : Entity_Id; begin pragma Assert (Nkind (Dec) = N_Protected_Type_Declaration); Pdef := Defining_Identifier (Dec); if Has_Discriminants (Pdef) then D := First_Discriminant (Pdef); while Present (D) loop D_Minal := Make_Defining_Identifier (Sloc (D), Chars => New_External_Name (Chars (D), 'D')); Set_Ekind (D_Minal, E_Constant); Set_Etype (D_Minal, Etype (D)); Set_Scope (D_Minal, Pdef); Set_Discriminal (D, D_Minal); Set_Discriminal_Link (D_Minal, D); Next_Discriminant (D); end loop; end if; end Set_Discriminals; ----------------- -- Set_Privals -- ----------------- procedure Set_Privals (Dec : Node_Id; Op : Node_Id; Loc : Source_Ptr) is P_Decl : Node_Id; P_Id : Entity_Id; Priv : Entity_Id; Def : Node_Id; Body_Ent : Entity_Id; Prec_Decl : constant Node_Id := Parent (Corresponding_Record_Type (Defining_Identifier (Dec))); Prec_Def : constant Entity_Id := Type_Definition (Prec_Decl); Obj_Decl : Node_Id; P_Subtype : Entity_Id; Assoc_L : constant Elist_Id := New_Elmt_List; Op_Id : Entity_Id; begin pragma Assert (Nkind (Dec) = N_Protected_Type_Declaration); pragma Assert (Nkind (Op) = N_Subprogram_Body or else Nkind (Op) = N_Entry_Body); Def := Protected_Definition (Dec); if Present (Private_Declarations (Def)) then P_Decl := First (Private_Declarations (Def)); while Present (P_Decl) loop if Nkind (P_Decl) = N_Component_Declaration then P_Id := Defining_Identifier (P_Decl); Priv := Make_Defining_Identifier (Loc, New_External_Name (Chars (P_Id), 'P')); Set_Ekind (Priv, E_Variable); Set_Etype (Priv, Etype (P_Id)); Set_Scope (Priv, Scope (P_Id)); Set_Esize (Priv, Esize (Etype (P_Id))); Set_Alignment (Priv, Alignment (Etype (P_Id))); -- If the type of the component is an itype, we must -- create a new itype for the corresponding prival in -- each protected operation, to avoid scoping problems. -- We create new itypes by copying the tree for the -- component definition. if Is_Itype (Etype (P_Id)) then Append_Elmt (P_Id, Assoc_L); Append_Elmt (Priv, Assoc_L); if Nkind (Op) = N_Entry_Body then Op_Id := Defining_Identifier (Op); else Op_Id := Defining_Unit_Name (Specification (Op)); end if; Discard_Node (New_Copy_Tree (P_Decl, Assoc_L, New_Scope => Op_Id)); end if; Set_Protected_Operation (P_Id, Op); Set_Prival (P_Id, Priv); end if; Next (P_Decl); end loop; end if; -- There is one more implicit private declaration: the object -- itself. A "prival" for this is attached to the protected -- body defining identifier. Body_Ent := Corresponding_Body (Dec); Priv := Make_Defining_Identifier (Sloc (Body_Ent), Chars => New_External_Name (Chars (Body_Ent), 'R')); -- Set the Etype to the implicit subtype of Protection created when -- the protected type declaration was expanded. This node will not -- be analyzed until it is used as the defining identifier for the -- renaming declaration in the protected operation body, and it will -- be needed in the references expanded before that body is expanded. -- Since the Protection field is aliased, set Is_Aliased as well. Obj_Decl := First (Component_Items (Component_List (Prec_Def))); while Chars (Defining_Identifier (Obj_Decl)) /= Name_uObject loop Next (Obj_Decl); end loop; P_Subtype := Etype (Defining_Identifier (Obj_Decl)); Set_Ekind (Priv, E_Variable); Set_Etype (Priv, P_Subtype); Set_Is_Aliased (Priv); Set_Object_Ref (Body_Ent, Priv); end Set_Privals; ---------------------------- -- Update_Prival_Subtypes -- ---------------------------- procedure Update_Prival_Subtypes (N : Node_Id) is function Process (N : Node_Id) return Traverse_Result; -- Update the etype of occurrences of privals whose etype does not -- match the current Etype of the prival entity itself. procedure Update_Array_Bounds (E : Entity_Id); -- Itypes generated for array expressions may depend on the -- determinants of the protected object, and need to be processed -- separately because they are not attached to the tree. procedure Update_Index_Types (N : Node_Id); -- Similarly, update the types of expressions in indexed components -- which may depend on other discriminants. ------------- -- Process -- ------------- function Process (N : Node_Id) return Traverse_Result is begin if Is_Entity_Name (N) then declare E : constant Entity_Id := Entity (N); begin if Present (E) and then (Ekind (E) = E_Constant or else Ekind (E) = E_Variable) and then Nkind (Parent (E)) = N_Object_Renaming_Declaration and then not Is_Scalar_Type (Etype (E)) and then Etype (N) /= Etype (E) then Set_Etype (N, Etype (Entity (Original_Node (N)))); Update_Index_Types (N); elsif Present (E) and then Ekind (E) = E_Constant and then Present (Discriminal_Link (E)) then Set_Etype (N, Etype (E)); end if; end; return OK; elsif Nkind (N) = N_Defining_Identifier or else Nkind (N) = N_Defining_Operator_Symbol or else Nkind (N) = N_Defining_Character_Literal then return Skip; elsif Nkind (N) = N_String_Literal then -- Array type, but bounds are constant return OK; elsif Nkind (N) = N_Object_Declaration and then Is_Itype (Etype (Defining_Identifier (N))) and then Is_Array_Type (Etype (Defining_Identifier (N))) then Update_Array_Bounds (Etype (Defining_Identifier (N))); return OK; -- For array components of discriminated records, use the -- base type directly, because it may depend indirectly -- on the discriminants of the protected type. Cleaner would -- be a systematic mechanism to compute actual subtypes of -- private components ??? elsif Nkind (N) in N_Has_Etype and then Present (Etype (N)) and then Is_Array_Type (Etype (N)) and then Nkind (N) = N_Selected_Component and then Has_Discriminants (Etype (Prefix (N))) then Set_Etype (N, Base_Type (Etype (N))); Update_Index_Types (N); return OK; else if Nkind (N) in N_Has_Etype and then Present (Etype (N)) and then Is_Itype (Etype (N)) then if Is_Array_Type (Etype (N)) then Update_Array_Bounds (Etype (N)); elsif Is_Scalar_Type (Etype (N)) then Update_Prival_Subtypes (Type_Low_Bound (Etype (N))); Update_Prival_Subtypes (Type_High_Bound (Etype (N))); end if; end if; return OK; end if; end Process; ------------------------- -- Update_Array_Bounds -- ------------------------- procedure Update_Array_Bounds (E : Entity_Id) is Ind : Node_Id; begin Ind := First_Index (E); while Present (Ind) loop Update_Prival_Subtypes (Type_Low_Bound (Etype (Ind))); Update_Prival_Subtypes (Type_High_Bound (Etype (Ind))); Next_Index (Ind); end loop; end Update_Array_Bounds; ------------------------ -- Update_Index_Types -- ------------------------ procedure Update_Index_Types (N : Node_Id) is Indx1 : Node_Id; I_Typ : Node_Id; begin -- If the prefix has an actual subtype that is different -- from the nominal one, update the types of the indices, -- so that the proper constraints are applied. Do not -- apply this transformation to a packed array, where the -- index type is computed for a byte array and is different -- from the source index. if Nkind (Parent (N)) = N_Indexed_Component and then not Is_Bit_Packed_Array (Etype (Prefix (Parent (N)))) then Indx1 := First (Expressions (Parent (N))); I_Typ := First_Index (Etype (N)); while Present (Indx1) and then Present (I_Typ) loop if not Is_Entity_Name (Indx1) then Set_Etype (Indx1, Base_Type (Etype (I_Typ))); end if; Next (Indx1); Next_Index (I_Typ); end loop; end if; end Update_Index_Types; procedure Traverse is new Traverse_Proc; -- Start of processing for Update_Prival_Subtypes begin Traverse (N); end Update_Prival_Subtypes; end Exp_Ch9;