+++ /dev/null
-------------------------------------------------------------------------------
--- --
--- GNAT COMPILER COMPONENTS --
--- --
--- E X P _ C H 9 --
--- --
--- B o d y --
--- --
--- $Revision: 1.3.10.1 $
--- --
--- Copyright (C) 1992-2001, 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 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 Tbuild; use Tbuild;
-with Types; use Types;
-with Uintp; use Uintp;
-with Opt;
-
-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 - <<index of first family member>> +
- -- 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 Array_Type (E : Entity_Id; Trec : Node_Id) return Entity_Id;
- -- Find the array type associated with an entry family in the
- -- associated record for the task type.
-
- 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. In
- -- order to simplify the work of the debugger, the prefix includes the
- -- characters PT.
-
- 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
- Expr : Node_Id;
- Num : Node_Id;
- Lo : Node_Id;
- Hi : Node_Id;
- Prev : Entity_Id;
- S : Node_Id;
- Ttyp : Entity_Id := Etype (Tsk);
-
- --------------------------
- -- Actual_Family_Offset --
- --------------------------
-
- function Actual_Family_Offset (Hi, Lo : Node_Id) return Node_Id;
- -- Compute difference between bounds of entry family.
-
- 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.
-
- function Actual_Discriminant_Ref (Bound : Node_Id) return Node_Id is
- Typ : 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;
-
- begin
- return
- Make_Op_Subtract (Sloc,
- Left_Opnd => Actual_Discriminant_Ref (Hi),
- Right_Opnd => Actual_Discriminant_Ref (Lo));
- end Actual_Family_Offset;
-
- 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
- P : Node_Id;
- Pdef : Entity_Id;
- Def : Node_Id := Protected_Definition (Parent (Typ));
- Body_Ent : constant Entity_Id := Corresponding_Body (Parent (Typ));
-
- 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
- Protection_Type := RE_Protection_Entry;
- 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 Restrictions (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;
-
- ----------------
- -- Array_Type --
- ----------------
-
- function Array_Type (E : Entity_Id; Trec : Node_Id) return Entity_Id is
- Arr : Entity_Id := First_Component (Trec);
-
- begin
- while Present (Arr) loop
- exit when Ekind (Arr) = E_Component
- and then Is_Array_Type (Etype (Arr))
- and then Chars (Arr) = Chars (E);
-
- Next_Component (Arr);
- end loop;
-
- -- This used to return Arr itself, but this caused problems
- -- when used in expanding a protected type, possibly because
- -- the record of which it is a component is not frozen yet.
- -- I am going to try the type instead. This may pose visibility
- -- problems. ???
-
- return Etype (Arr);
- end Array_Type;
-
- -----------------------
- -- 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);
- Bdef : Entity_Id;
- Bspec : Node_Id;
- Op_Decls : List_Id := New_List;
-
- begin
- Bdef :=
- Make_Defining_Identifier (Loc, Chars (Barrier_Function (Ent)));
- Bspec := Build_Barrier_Function_Specification (Bdef, Loc);
-
- -- <object pointer declaration>
- -- <discriminant renamings>
- -- <private object renamings>
- -- 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, New_Internal_Name ('I'));
-
- 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
- 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_Girder_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;
-
- begin
- -- Nothing to do if we already built a master entity for this scope
- -- or if there is no task hierarchy.
-
- if Has_Master_Entity (Scope (E))
- or else Restrictions (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);
- Set_Has_Master_Entity (Scope (E));
-
- -- 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);
- Edef : Entity_Id;
- Espec : Node_Id;
- Op_Decls : List_Id := New_List;
- 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);
-
- -- <object pointer declaration>
- -- 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 Restrictions (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 Restrictions (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 Restrictions (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
- 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_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;
-
- if Nkind (Specification (Decl)) = N_Procedure_Specification then
- return
- Make_Procedure_Specification (Loc,
- Defining_Unit_Name =>
- Make_Defining_Identifier (Loc,
- Chars => Build_Selected_Name (Protnm, Nam, Append_Char)),
- Parameter_Specifications => New_Plist);
-
- else
- New_Spec :=
- Make_Function_Specification (Loc,
- Defining_Unit_Name =>
- Make_Defining_Identifier (Loc,
- Chars => Build_Selected_Name (Protnm, Nam, Append_Char)),
- 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;
- Op_Def : Entity_Id;
- Sub_Name : Name_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;
- Unlock_Name : Node_Id;
- Unlock_Stmt : Node_Id;
- Service_Name : Node_Id;
- Service_Stmt : Node_Id;
- R : Node_Id;
- Return_Stmt : Node_Id := Empty;
- Pre_Stmts : List_Id := No_List;
- -- Initializations to avoid spurious warnings from GCC3.
- 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);
- Op_Def := Defining_Unit_Name (Op_Spec);
- Exc_Safe := Is_Exception_Safe (N);
-
- Sub_Name := Chars (Defining_Unit_Name (Specification (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)
- then
- if Abort_Allowed
- or else Restrictions (No_Entry_Queue) = False
- or else Number_Entries (Pid) > 1
- then
- Lock_Name := New_Reference_To (RTE (RE_Lock_Entries), Loc);
- Unlock_Name := New_Reference_To (RTE (RE_Unlock_Entries), Loc);
- Service_Name := New_Reference_To (RTE (RE_Service_Entries), Loc);
-
- else
- Lock_Name := New_Reference_To (RTE (RE_Lock_Entry), Loc);
- Unlock_Name := New_Reference_To (RTE (RE_Unlock_Entry), Loc);
- Service_Name := New_Reference_To (RTE (RE_Service_Entry), Loc);
- end if;
-
- else
- Lock_Name := New_Reference_To (RTE (RE_Lock), Loc);
- Unlock_Name := New_Reference_To (RTE (RE_Unlock), Loc);
- Service_Name := Empty;
- 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;
-
- if Service_Name /= Empty then
- Service_Stmt := Make_Procedure_Call_Statement (Loc,
- Name => Service_Name,
- Parameter_Associations =>
- New_List (New_Copy_Tree (Object_Parm)));
- Append (Service_Stmt, Stmts);
- end if;
-
- Unlock_Stmt :=
- Make_Procedure_Call_Statement (Loc,
- Name => Unlock_Name,
- Parameter_Associations => New_List (
- New_Copy_Tree (Object_Parm)));
- Append (Unlock_Stmt, 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 : 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) := 'P';
- Name_Buffer (Name_Len + 2) := 'T';
- Name_Buffer (Name_Len + 3) := '_';
- Name_Buffer (Name_Len + 4) := '_';
-
- Name_Len := Name_Len + 4;
- 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 => <entry index>;
- -- 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);
- 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;
- Stats : List_Id := New_List;
- 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
- Build_Protected_Subprogram_Call
- (N, Ename, Convert_Concurrent (Concval, Conctyp));
- Analyze (N);
- 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 Restrictions (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 ('I')),
- 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 Restrictions (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 => <entry index>;
- -- 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 was 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 : 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_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);
- Sub_Name : Name_Id;
- 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);
- Sub_Name := Chars (Defining_Unit_Name (Specification (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))),
-
- 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)),
-
- 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 Restrictions (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));
- 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);
-
- Insert_After (N, Decl1);
-
- -- Create Equivalent_Type, a record with two components for an
- -- an access to object an an access to subprogram.
-
- Comps := New_List (
- Make_Component_Declaration (Loc,
- Defining_Identifier =>
- Make_Defining_Identifier (Loc, New_Internal_Name ('P')),
- Subtype_Indication =>
- New_Occurrence_Of (RTE (RE_Address), Loc)),
-
- Make_Component_Declaration (Loc,
- Defining_Identifier =>
- Make_Defining_Identifier (Loc, New_Internal_Name ('S')),
- 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)));
-
- 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);
- Func : Node_Id;
- B_F : Node_Id;
- Prot : constant Entity_Id := Scope (Ent);
- Spec_Decl : Node_Id := Parent (Prot);
- Body_Decl : Node_Id;
- Cond : Node_Id := Condition (Entry_Body_Formal_Part (N));
-
- begin
- -- 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, N, Loc);
- Set_Scope (Func, Scope (Prot));
- else
- Analyze (Cond);
- 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;
-
- elsif Present (Renamed_Object (Entity (Cond)))
- and then
- Nkind (Renamed_Object (Entity (Cond))) = N_Selected_Component
- and then
- Chars (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 (Boolean_Entry_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 ('I')));
- 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);
- -- <statement sequence from N_Accept_Statement node>
- -- Complete_Rendezvous;
- -- <<Lnn>>
- --
- -- exception
- -- when ... =>
- -- <exception handler from N_Accept_Statement node>
- -- Complete_Rendezvous;
- -- when ... =>
- -- <exception handler from N_Accept_Statement node>
- -- 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));
- 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
- 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.
-
- Block :=
- Make_Block_Statement (Loc,
- Declarations => Declarations (N),
- Handled_Statement_Sequence => Build_Accept_Body (N));
-
- -- Prepend call to Accept_Call to main statement sequence
-
- 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)));
-
- Prepend (Call, Statements (Stats));
- Analyze (Call);
-
- -- 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 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 => <entry index>;
- -- Uninterpreted_Data => P'Address;
- -- Mode => Asynchronous_Call;
- -- Block => Bnn);
- -- if Enqueued (Bnn) then
- -- <abortable part>
- -- 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 => <entry index>;
- -- 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);
-
- Ecall : Node_Id;
- Astats : List_Id := Statements (Abrt);
- 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 => <entry index>;
- -- 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 => <entry index>;
- -- 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 => <entry index>;
- -- 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);
- Next_Op : Node_Id;
- Dec : Node_Id := Parent (Current_Scope);
- Ent_Formals : Node_Id := Entry_Body_Formal_Part (N);
- Index_Spec : Node_Id := Entry_Index_Specification (Ent_Formals);
-
- 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
- Append_List_To (Declarations (N),
- Index_Constant_Declaration
- (N, Defining_Identifier (Index_Spec), Defining_Identifier (Dec)));
- 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, Next_Op, Loc);
- 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 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,
- 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
- -- <discriminant renamings>
- -- <private object renamings>
- -- begin
- -- return <barrier expression>;
- -- end entB;
-
- -- procedure pprocN (_object : in out poV;...) is
- -- <discriminant renamings>
- -- <private object renamings>
- -- begin
- -- <sequence of statements>
- -- 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
- -- <discriminant renamings>
- -- <private object renamings>
- -- begin
- -- <sequence of statements>
- -- 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
- -- <discriminant renamings>
- -- <private object renamings>
- -- type poVP is access poV;
- -- _Object : ptVP := ptVP!(O);
- -- begin
- -- begin
- -- <statement sequence>
- -- 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 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)) 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 Restrictions (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 <kind>Protection
- -- [(<entry count> [, <handler count>])];
- -- [entry_family : array (bounds) of Void;]
- -- <private data fields>
- -- 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 : 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;
- Nam : Name_Id;
- 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
- Protection_Subtype :=
- New_Reference_To (RTE (RE_Protection_Entry), Loc);
-
- 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 Restrictions (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),
- 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)),
- Subtype_Indication =>
- New_Copy_Tree (Subtype_Indication (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.
-
- E_Count := 0;
-
- Comp := First (Visible_Declarations (Pdef));
-
- while Present (Comp) loop
- if Nkind (Comp) = N_Subprogram_Declaration 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);
- Nam := Chars (Comp_Id);
- Edef :=
- Make_Defining_Identifier (Loc,
- Build_Selected_Name (Protnm, New_Internal_Name ('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_Internal_Name ('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);
- Nam := Chars (Comp_Id);
- Edef :=
- Make_Defining_Identifier (Loc,
- Build_Selected_Name (Protnm, New_Internal_Name ('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_Internal_Name ('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 Restrictions (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 Restrictions (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
- -- <discriminant renamings>
- -- <private object renamings>
- -- type poVP is access poV;
- -- _Object : ptVP := ptVP!(O);
- --
- -- begin
- -- begin
- -- <start of statement sequence for entry>
- --
- -- -- Requeue from one protected entry body to another protected
- -- -- entry.
- --
- -- Requeue_Protected_Entry (
- -- _object._object'Access,
- -- new._object'Access,
- -- E,
- -- Abort_Present);
- -- return;
- --
- -- <some more of the statement sequence for entry>
- --
- -- -- Requeue from an entry body to a task entry.
- --
- -- Requeue_Protected_To_Task_Entry (
- -- New._task_id,
- -- E,
- -- Abort_Present);
- -- return;
- --
- -- <rest of statement sequence for entry>
- -- 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);
- -- <start of statement sequence for accept statement>
- -- Requeue_Task_Entry (New._task_id, E, Abort_Present);
- -- goto Lnn;
- -- <rest of statement sequence for accept statement>
- -- <<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);
- -- <start of statement sequence for accept statement>
- -- Requeue_Task_To_Protected_Entry (
- -- new._object'Access,
- -- E,
- -- Abort_Present);
- -- newS (new, Pnn);
- -- goto Lnn;
- -- <rest of statement sequence for accept statement>
- -- <<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
- if Abort_Present (N) then
- Abortable := New_Occurrence_Of (Standard_True, Loc);
- else
- Abortable := New_Occurrence_Of (Standard_False, Loc);
- end if;
-
- -- 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);
-
- Accept_Case : List_Id;
- Accept_List : List_Id := New_List;
-
- Alt : Node_Id;
- Alt_List : List_Id := New_List;
- Alt_Stats : List_Id;
- Ann : Entity_Id := Empty;
-
- Block : Node_Id;
- Check_Guard : Boolean := True;
- Decls : List_Id := New_List;
- Stats : List_Id := New_List;
-
- Body_List : List_Id := New_List;
- Trailing_List : 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 : 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))));
-
- 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));
-
- 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 : 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 := <delay mode>;
- -- 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
- -- <declarations>
- -- begin
- -- <statements>
- -- 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;
- -- <declarations>
- -- System.Task_Stages.Complete_Activation;
- -- <statements>
- -- 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
- 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;
- -- _Task_Name : Task_Image_Type := new String'(task_name_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.
-
- -- The _Task_Name field is present only if a Task_Name pragma appears in
- -- the task definition. The expression captures the argument that was
- -- present in the pragma, and is used to provide the Task_Id 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;
-
- begin
- if Present (Corresponding_Record_Type (Tasktyp)) then
- return;
-
- else
- Rec_Decl := Build_Corresponding_Record (N, Tasktyp, Loc);
- Rec_Ent := Defining_Identifier (Rec_Decl);
- Cdecls := Component_Items
- (Component_List (Type_Definition (Rec_Decl)));
- end if;
-
- 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),
- Subtype_Indication => New_Reference_To (RTE (RO_ST_Task_ID), Loc)));
-
- -- 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
- Append_To (Cdecls,
- Make_Component_Declaration (Loc,
- Defining_Identifier =>
- Make_Defining_Identifier (Loc, Name_uPriority),
- Subtype_Indication => New_Reference_To (Standard_Integer, Loc),
- Expression => New_Copy (
- Expression (First (
- Pragma_Argument_Associations (
- Find_Task_Or_Protected_Pragma
- (Taskdef, Name_Priority)))))));
- 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),
-
- 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),
- 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;
-
- -- Add the _Task_Name component if a Task_Name pragma is present
-
- if Present (Taskdef) and then Has_Task_Name_Pragma (Taskdef) then
- Append_To (Cdecls,
- Make_Component_Declaration (Loc,
- Defining_Identifier =>
- Make_Defining_Identifier (Loc, Name_uTask_Info),
- Subtype_Indication =>
- New_Reference_To (RTE (RE_Task_Image_Type), Loc),
- Expression =>
- Make_Allocator (Loc,
- Expression =>
- Make_Qualified_Expression (Loc,
- Subtype_Mark =>
- New_Occurrence_Of (Standard_String, Loc),
- Expression =>
- New_Copy (
- Expression (First (
- Pragma_Argument_Associations (
- Find_Task_Or_Protected_Pragma
- (Taskdef, Name_Task_Name)))))))));
- 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);
-
- -- 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 (N, 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 := <entry index>;
- -- DX : Duration := To_Duration (D);
- -- M : Delay_Mode := <discriminant>;
- -- P : parms := (parm, parm, parm);
-
- -- begin
- -- Timed_Protected_Entry_Call (<acceptor-task>, 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 := <entry index>;
- -- DX : Duration := To_Duration (D);
- -- M : Delay_Mode := <discriminant>;
- -- P : parms := (parm, parm, parm);
-
- -- begin
- -- Timed_Protected_Entry_Call (<object>'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 a Duration and a Delay_Mode object used 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));
-
- -- In case some garbage is following the Cancel_Param, remove.
-
- Dummy := Next (Parm);
-
- -- Remove the mode of the Protected_Entry_Call call, the
- -- Communication_Block of the Protected_Entry_Call call, and add a
- -- 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 Restrictions (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 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), Op, Sloc (N));
- 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 : 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 ('I'));
-
- 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 : Node_Id;
- Pnam : Name_Id;
- Args : List_Id;
- L : List_Id := New_List;
-
- 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.
-
- Ptyp := Corresponding_Concurrent_Type (Protect_Rec);
- Pnam := Chars (Ptyp);
-
- -- 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 (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_Entries (Ptyp)
- 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.
-
- Append_To (Args,
- Make_Attribute_Reference (Loc,
- Prefix => Make_Identifier (Loc, Name_uInit),
- Attribute_Name => Name_Address));
-
- if Has_Entries (Ptyp) 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 Restrictions (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;
-
- else
- Append_To (Args, Make_Null (Loc));
- Append_To (Args, Make_Null (Loc));
- end if;
-
- if Abort_Allowed
- or else Restrictions (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));
-
- 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));
-
- declare
- Args : List_Id := New_List;
- Table : List_Id := New_List;
- Ritem : Node_Id := First_Rep_Item (Ptyp);
-
- begin
- -- 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));
-
- -- 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 : Node_Id :=
- First (Pragma_Argument_Associations (Ritem));
- Interrupt : Node_Id :=
- Next (Handler);
-
- begin
- Append_To (Table,
- Make_Aggregate (Loc, Expressions => New_List (
- Duplicate_Subexpr (Expression (Interrupt)),
- Make_Attribute_Reference (Loc,
- Prefix => Make_Selected_Component (Loc,
- Make_Identifier (Loc, Name_uInit),
- Duplicate_Subexpr (Expression (Handler))),
- Attribute_Name => Name_Access))));
- end;
- end if;
-
- Next_Rep_Item (Ritem);
- end loop;
-
- -- Appends the table argument we just built.
- Append_To (Args, Make_Aggregate (Loc, Table));
-
- -- Appends 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;
-
- -- 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 Restrictions (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_Info 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,
- Make_Selected_Component (Loc,
- Prefix => Make_Identifier (Loc, Name_uInit),
- Selector_Name => Make_Identifier (Loc, Name_uTask_Info)));
-
- else
- Append_To (Args, Make_Identifier (Loc, Name_uTask_Id));
- 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;
- Op : Node_Id;
- Loc : Source_Ptr)
- 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_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;
- New_Decl : Entity_Id;
- Assoc_L : 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;
-
- New_Decl := 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_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.
-
- -------------
- -- Process --
- -------------
-
- function Process (N : Node_Id) return Traverse_Result is
- begin
- if Is_Entity_Name (N) then
- declare
- E : 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))));
-
- -- 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
- declare
- Indx1 : Node_Id;
- I_Typ : Node_Id;
-
- begin
- 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;
- end if;
-
- 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;
-
- 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;
-
- procedure Traverse is new Traverse_Proc;
-
- -- Start of processing for Update_Prival_Subtypes
-
- begin
- Traverse (N);
- end Update_Prival_Subtypes;
-
-end Exp_Ch9;
projects / msp430-gcc.git / blobdiff