------------------------------------------------------------------------------ -- -- -- GNAT COMPILER COMPONENTS -- -- -- -- E X P _ C H 9 -- -- -- -- S p e c -- -- -- -- Copyright (C) 1992-2009, Free Software Foundation, Inc. -- -- -- -- GNAT is free software; you can redistribute it and/or modify it under -- -- terms of the GNU General Public License as published by the Free Soft- -- -- ware Foundation; either version 3, or (at your option) any later ver- -- -- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License -- -- for more details. You should have received a copy of the GNU General -- -- Public License distributed with GNAT; see file COPYING3. If not, go to -- -- http://www.gnu.org/licenses for a complete copy of the license. -- -- -- -- GNAT was originally developed by the GNAT team at New York University. -- -- Extensive contributions were provided by Ada Core Technologies Inc. -- -- -- ------------------------------------------------------------------------------ -- Expand routines for chapter 9 constructs with Types; use Types; package Exp_Ch9 is type Subprogram_Protection_Mode is (Dispatching_Mode, Protected_Mode, Unprotected_Mode); -- This type is used to distinguish the different protection modes of a -- protected subprogram. procedure Build_Activation_Chain_Entity (N : Node_Id); -- Given a declaration N of an object that is a task, or contains tasks -- (other than allocators to tasks) this routine ensures that an activation -- chain has been declared in the appropriate scope, building the required -- declaration for the chain variable if not. The name of this variable -- is always _Chain and it is accessed by name. function Build_Call_With_Task (N : Node_Id; E : Entity_Id) return Node_Id; -- N is a node representing the name of a task or an access to a task. -- The value returned is a call to the function whose name is the entity -- E (typically a runtime routine entity obtained using RTE) with the -- Task_Id of the associated task as the parameter. The caller is -- responsible for analyzing and resolving the resulting tree. 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_Names (Conc_Typ : Entity_Id) return Node_Id; -- Create the statements which populate the entry names array of a task or -- protected type. The statements are wrapped inside a block due to a local -- declaration. procedure Build_Master_Entity (E : Entity_Id); -- Given an entity E for the declaration of an object containing tasks -- or of a type declaration for an allocator whose designated type is a -- task or contains tasks, this routine marks the appropriate enclosing -- context as a master, and also declares a variable called _Master in -- the current declarative part which captures the value of Current_Master -- (if not already built by a prior call). We build this object (instead -- of just calling Current_Master) for two reasons. First it is clearly -- more efficient to call Current_Master only once for a bunch of tasks -- in the same declarative part, and second it makes things easier in -- generating the initialization routines, since they can just reference -- the object _Master by name, and they will get the proper Current_Master -- value at the outer level, and copy in the parameter value for the outer -- initialization call if the call is for a nested component). Note that -- in the case of nested packages, we only really need to make one such -- object at the outer level, but it is much easier to generate one per -- declarative part. function Build_Private_Protected_Declaration (N : Node_Id) return Entity_Id; -- A subprogram body without a previous spec that appears in a protected -- body must be expanded separately to create a subprogram declaration -- for it, in order to resolve internal calls to it from other protected -- operations. It would seem that no locking version of the operation is -- needed, but in fact, in Ada 2005 the subprogram may be used in a call- -- back, and therefore a protected version of the operation must be -- generated as well. function Build_Protected_Sub_Specification (N : Node_Id; Prot_Typ : Entity_Id; Mode : Subprogram_Protection_Mode) return Node_Id; -- Build the specification for protected subprogram. This is called when -- expanding a protected type, and also when expanding the declaration for -- an Access_To_Protected_Subprogram type. In the latter case, Prot_Typ is -- empty, and the first parameter of the signature of the protected op is -- of type System.Address. procedure Build_Protected_Subprogram_Call (N : Node_Id; Name : Node_Id; Rec : Node_Id; External : Boolean := True); -- The node N is a subprogram or entry call to a protected subprogram. This -- procedure rewrites this call with the appropriate expansion. Name is the -- subprogram, and Rec is the record corresponding to the protected object. -- External is False if the call is to another protected subprogram within -- the same object. procedure Build_Task_Activation_Call (N : Node_Id); -- This procedure is called for constructs that can be task activators, -- i.e. task bodies, subprogram bodies, package bodies and blocks. If the -- construct is a task activator (as indicated by the non-empty setting of -- Activation_Chain_Entity, either in the construct, or, in the case of a -- package body, in its associated package spec), then a call to -- Activate_Tasks with this entity as the single parameter is inserted at -- the start of the statements of the activator. procedure Build_Task_Allocate_Block (Actions : List_Id; N : Node_Id; Args : List_Id); -- This routine is used in the case of allocators where the designated type -- is a task or contains tasks. In this case, the normal initialize call -- is replaced by: -- -- blockname : label; -- blockname : declare -- _Chain : Activation_Chain; -- -- procedure _Expunge is -- begin -- Expunge_Unactivated_Tasks (_Chain); -- end; -- -- begin -- Init (Args); -- Activate_Tasks (_Chain); -- at end -- _Expunge; -- end; -- -- to get the task or tasks created and initialized. The expunge call -- ensures that any tasks that get created but not activated due to an -- exception are properly expunged (it has no effect in the normal case). -- The argument N is the allocator, and Args is the list of arguments for -- the initialization call, constructed by the caller, which uses the -- Master_Id of the access type as the _Master parameter, and _Chain -- (defined above) as the _Chain parameter. procedure Build_Task_Allocate_Block_With_Init_Stmts (Actions : List_Id; N : Node_Id; Init_Stmts : List_Id); -- Ada 2005 (AI-287): Similar to previous routine, but used to expand -- allocated aggregates with default initialized components. Init_Stmts -- contains the list of statements required to initialize the allocated -- aggregate. It replaces the call to Init (Args) done by -- Build_Task_Allocate_Block. function Build_Wrapper_Spec (Subp_Id : Entity_Id; Obj_Typ : Entity_Id; Formals : List_Id) return Node_Id; -- Ada 2005 (AI-345): Build the specification of a primitive operation -- associated with a protected or task type. This is required to implement -- dispatching calls through interfaces. Subp_Id is the primitive to be -- wrapped, Obj_Typ is the type of the newly added formal parameter to -- handle object notation, Formals are the original entry formals that -- will be explicitly replicated. function Concurrent_Ref (N : Node_Id) return Node_Id; -- Given the name of a concurrent object (task or protected object), or -- the name of an access to a concurrent object, this function returns an -- expression referencing the associated Task_Id or Protection object, -- respectively. Note that a special case is when the name is a reference -- to a task type name. This can only happen within a task body, and the -- meaning is to get the Task_Id for the currently executing task. function Convert_Concurrent (N : Node_Id; Typ : Entity_Id) return Node_Id; -- N is an expression of type Typ. If the type is not a concurrent type -- then it is returned unchanged. If it is a task or protected reference, -- Convert_Concurrent creates an unchecked conversion node from this -- expression to the corresponding concurrent record type value. We need -- this in any situation where the concurrent type is used, because the -- actual concurrent object is an object of the corresponding concurrent -- type, and manipulations on the concurrent object actually manipulate the -- corresponding object of the record type. function Entry_Index_Expression (Sloc : Source_Ptr; Ent : Entity_Id; Index : Node_Id; Ttyp : Entity_Id) return Node_Id; -- Returns an expression to compute a task entry index given the name of -- the entry or entry family. For the case of a task entry family, the -- Index parameter contains the expression for the subscript. Ttyp is the -- task type. procedure Establish_Task_Master (N : Node_Id); -- Given a subprogram body, or a block statement, or a task body, this -- procedure makes the necessary transformations required of a task master -- (add Enter_Master call at start, and establish a cleanup routine to make -- sure Complete_Master is called on exit). procedure Expand_Access_Protected_Subprogram_Type (N : Node_Id); -- Build Equivalent_Type for an Access_To_Protected_Subprogram. -- Equivalent_Type is a record type with two components: a pointer to the -- protected object, and a pointer to the operation itself. procedure Expand_Accept_Declarations (N : Node_Id; Ent : Entity_Id); -- Expand declarations required for accept statement. See bodies of both -- Expand_Accept_Declarations and Expand_N_Accept_Statement for full -- details of the nature and use of these declarations, which are inserted -- immediately before the accept node N. The second argument is the entity -- for the corresponding entry. procedure Expand_Entry_Barrier (N : Node_Id; Ent : Entity_Id); -- Expand the entry barrier into a function. This is called directly -- from Analyze_Entry_Body so that the discriminals and privals of the -- barrier can be attached to the function declaration list, and a new -- set prepared for the entry body procedure, before the entry body -- statement sequence can be expanded. The resulting function is analyzed -- now, within the context of the protected object, to resolve calls to -- other protected functions. procedure Expand_N_Abort_Statement (N : Node_Id); procedure Expand_N_Accept_Statement (N : Node_Id); procedure Expand_N_Asynchronous_Select (N : Node_Id); procedure Expand_N_Conditional_Entry_Call (N : Node_Id); procedure Expand_N_Delay_Relative_Statement (N : Node_Id); procedure Expand_N_Delay_Until_Statement (N : Node_Id); procedure Expand_N_Entry_Body (N : Node_Id); procedure Expand_N_Entry_Call_Statement (N : Node_Id); procedure Expand_N_Entry_Declaration (N : Node_Id); procedure Expand_N_Protected_Body (N : Node_Id); procedure Expand_N_Protected_Type_Declaration (N : Node_Id); -- Expands protected type declarations. This results, among other things, -- in the declaration of a record type for the representation of protected -- objects and (if there are entries) in an entry service procedure. The -- Protection value used by the GNARL to control the object will always be -- the first field of the record, and the entry service procedure spec (if -- it exists) will always immediately follow the record declaration. This -- allows these two nodes to be found from the type, without benefit of -- further attributes, using Corresponding_Record. procedure Expand_N_Requeue_Statement (N : Node_Id); procedure Expand_N_Selective_Accept (N : Node_Id); procedure Expand_N_Single_Task_Declaration (N : Node_Id); procedure Expand_N_Task_Body (N : Node_Id); procedure Expand_N_Task_Type_Declaration (N : Node_Id); procedure Expand_N_Timed_Entry_Call (N : Node_Id); procedure Expand_Protected_Body_Declarations (N : Node_Id; Spec_Id : Entity_Id); -- Expand declarations required for a protected body. See bodies of both -- Expand_Protected_Body_Declarations and Expand_N_Protected_Body for full -- details of the nature and use of these declarations. The second argument -- is the entity for the corresponding protected type declaration. function External_Subprogram (E : Entity_Id) return Entity_Id; -- return the external version of a protected operation, which locks -- the object before invoking the internal protected subprogram body. function First_Protected_Operation (D : List_Id) return Node_Id; -- Given the declarations list for a protected body, find the -- first protected operation body. procedure Install_Private_Data_Declarations (Loc : Source_Ptr; Spec_Id : Entity_Id; Conc_Typ : Entity_Id; Body_Nod : Node_Id; Decls : List_Id; Barrier : Boolean := False; Family : Boolean := False); -- This routines generates several types, objects and object renamings used -- in the handling of discriminants and private components of protected and -- task types. It also generates the entry index for entry families. Formal -- Spec_Id denotes an entry, entry family or a subprogram, Conc_Typ is the -- concurrent type where Spec_Id resides, Body_Nod is the corresponding -- body of Spec_Id, Decls are the declarations of the subprogram or entry. -- Flag Barrier denotes whether the context is an entry barrier function. -- Flag Family is used in conjunction with Barrier to denote a barrier for -- an entry family. -- -- The generated types, entities and renamings are: -- -- * If flag Barrier is set or Spec_Id denotes a protected entry or an -- entry family, generate: -- -- type prot_typVP is access prot_typV; -- _object : prot_typVP := prot_typV (_O); -- -- where prot_typV is the corresponding record of a protected type and -- _O is a formal parameter representing the concurrent object of either -- the barrier function or the entry (family). -- -- * If Conc_Typ is a protected type, create a renaming for the Protection -- field _object: -- -- conc_typR : protection_typ renames _object._object; -- -- * If Conc_Typ has discriminants, create renamings of the form: -- -- discr_nameD : discr_typ renames _object.discr_name; -- or -- discr_nameD : discr_typ renames _task.discr_name; -- -- * If Conc_Typ denotes a protected type and has private components, -- generate renamings of the form: -- -- comp_name : comp_typ renames _object.comp_name; -- -- * Finally, is flag Barrier and Family are set or Spec_Id denotes an -- entry family, generate the entry index constant: -- -- subtype Jnn is range Low .. High; -- J : constant Jnn := -- Jnn'Val (_E - + Jnn'Pos (Jnn'First)); -- -- All the above declarations are inserted in the order shown to the front -- of Decls. function Make_Task_Create_Call (Task_Rec : Entity_Id) return Node_Id; -- Given the entity of the record type created for a task type, build -- the call to Create_Task function Make_Initialize_Protection (Protect_Rec : Entity_Id) return List_Id; -- Given the entity of the record type created for a protected type, build -- a list of statements needed for proper initialization of the object. function Next_Protected_Operation (N : Node_Id) return Node_Id; -- Given a protected operation node (a subprogram or entry body), find the -- following node in the declarations list. procedure Set_Discriminals (Dec : Node_Id); -- Replace discriminals in a protected type for use by the next protected -- operation on the type. Each operation needs a new set of discriminals, -- since it needs a unique renaming of the discriminant fields in the -- record used to implement the protected type. end Exp_Ch9;