1------------------------------------------------------------------------------ 2-- -- 3-- GNAT COMPILER COMPONENTS -- 4-- -- 5-- E X P _ C H 9 -- 6-- -- 7-- S p e c -- 8-- -- 9-- Copyright (C) 1992-2019, Free Software Foundation, Inc. -- 10-- -- 11-- GNAT is free software; you can redistribute it and/or modify it under -- 12-- terms of the GNU General Public License as published by the Free Soft- -- 13-- ware Foundation; either version 3, or (at your option) any later ver- -- 14-- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- 15-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- 16-- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License -- 17-- for more details. You should have received a copy of the GNU General -- 18-- Public License distributed with GNAT; see file COPYING3. If not, go to -- 19-- http://www.gnu.org/licenses for a complete copy of the license. -- 20-- -- 21-- GNAT was originally developed by the GNAT team at New York University. -- 22-- Extensive contributions were provided by Ada Core Technologies Inc. -- 23-- -- 24------------------------------------------------------------------------------ 25 26-- Expand routines for chapter 9 constructs 27 28with Types; use Types; 29 30package Exp_Ch9 is 31 32 type Subprogram_Protection_Mode is 33 (Dispatching_Mode, 34 Protected_Mode, 35 Unprotected_Mode); 36 -- This type is used to distinguish the different protection modes of a 37 -- protected subprogram. 38 39 procedure Build_Activation_Chain_Entity (N : Node_Id); 40 -- Given a declaration N of an object that is a task, or contains tasks 41 -- (other than allocators to tasks) this routine ensures that an activation 42 -- chain has been declared in the appropriate scope, building the required 43 -- declaration for the chain variable if not. The name of this variable 44 -- is always _Chain and it is accessed by name. 45 46 function Build_Call_With_Task (N : Node_Id; E : Entity_Id) return Node_Id; 47 -- N is a node representing the name of a task or an access to a task. 48 -- The value returned is a call to the function whose name is the entity 49 -- E (typically a runtime routine entity obtained using RTE) with the 50 -- Task_Id of the associated task as the parameter. The caller is 51 -- responsible for analyzing and resolving the resulting tree. 52 53 procedure Build_Class_Wide_Master (Typ : Entity_Id); 54 -- Given an access-to-limited class-wide type or an access-to-limited 55 -- interface, ensure that the designated type has a _master and generate 56 -- a renaming of the said master to service the access type. 57 58 procedure Build_Master_Entity (Obj_Or_Typ : Entity_Id); 59 -- Given the name of an object or a type which is either a task, contains 60 -- tasks or designates tasks, create a _master in the appropriate scope 61 -- which captures the value of Current_Master. Mark the nearest enclosing 62 -- body or block as being a task master. 63 64 procedure Build_Master_Renaming 65 (Ptr_Typ : Entity_Id; 66 Ins_Nod : Node_Id := Empty); 67 -- Given an access type Ptr_Typ whose designated type is either a task or 68 -- contains tasks, create a renaming of the form: 69 -- 70 -- <Ptr_Typ>M : Master_Id renames _Master; 71 -- 72 -- where _master denotes the task master of the enclosing context. Ins_Nod 73 -- is used to provide a specific insertion node for the renaming. 74 75 function Build_Private_Protected_Declaration (N : Node_Id) return Entity_Id; 76 -- A subprogram body without a previous spec that appears in a protected 77 -- body must be expanded separately to create a subprogram declaration 78 -- for it, in order to resolve internal calls to it from other protected 79 -- operations. It would seem that no locking version of the operation is 80 -- needed, but in fact, in Ada 2005 the subprogram may be used in a call- 81 -- back, and therefore a protected version of the operation must be 82 -- generated as well. 83 -- 84 -- Possibly factor this with Exp_Dist.Copy_Specification ??? 85 86 function Build_Protected_Sub_Specification 87 (N : Node_Id; 88 Prot_Typ : Entity_Id; 89 Mode : Subprogram_Protection_Mode) return Node_Id; 90 -- Build the specification for protected subprogram. This is called when 91 -- expanding a protected type, and also when expanding the declaration for 92 -- an Access_To_Protected_Subprogram type. In the latter case, Prot_Typ is 93 -- empty, and the first parameter of the signature of the protected op is 94 -- of type System.Address. 95 96 procedure Build_Protected_Subprogram_Call 97 (N : Node_Id; 98 Name : Node_Id; 99 Rec : Node_Id; 100 External : Boolean := True); 101 -- The node N is a subprogram or entry call to a protected subprogram. This 102 -- procedure rewrites this call with the appropriate expansion. Name is the 103 -- subprogram, and Rec is the record corresponding to the protected object. 104 -- External is False if the call is to another protected subprogram within 105 -- the same object. 106 107 procedure Build_Protected_Subprogram_Call_Cleanup 108 (Op_Spec : Node_Id; 109 Conc_Typ : Node_Id; 110 Loc : Source_Ptr; 111 Stmts : List_Id); 112 -- Append to Stmts the cleanups after a call to a protected subprogram 113 -- whose specification is Op_Spec. Conc_Typ is the concurrent type and Loc 114 -- the sloc for appended statements. The cleanup will either unlock the 115 -- protected object or serve pending entries. 116 117 procedure Build_Task_Activation_Call (N : Node_Id); 118 -- This procedure is called for constructs that can be task activators, 119 -- i.e. task bodies, subprogram bodies, package bodies and blocks. If the 120 -- construct is a task activator (as indicated by the non-empty setting of 121 -- Activation_Chain_Entity, either in the construct, or, in the case of a 122 -- package body, in its associated package spec), then a call to 123 -- Activate_Tasks with this entity as the single parameter is inserted at 124 -- the start of the statements of the activator. 125 126 procedure Build_Task_Allocate_Block 127 (Actions : List_Id; 128 N : Node_Id; 129 Args : List_Id); 130 -- This routine is used in the case of allocators where the designated type 131 -- is a task or contains tasks. In this case, the normal initialize call 132 -- is replaced by: 133 -- 134 -- blockname : label; 135 -- blockname : declare 136 -- _Chain : Activation_Chain; 137 -- 138 -- procedure _Expunge is 139 -- begin 140 -- Expunge_Unactivated_Tasks (_Chain); 141 -- end; 142 -- 143 -- begin 144 -- Init (Args); 145 -- Activate_Tasks (_Chain); 146 -- at end 147 -- _Expunge; 148 -- end; 149 -- 150 -- to get the task or tasks created and initialized. The expunge call 151 -- ensures that any tasks that get created but not activated due to an 152 -- exception are properly expunged (it has no effect in the normal case). 153 -- The argument N is the allocator, and Args is the list of arguments for 154 -- the initialization call, constructed by the caller, which uses the 155 -- Master_Id of the access type as the _Master parameter, and _Chain 156 -- (defined above) as the _Chain parameter. 157 158 procedure Build_Task_Allocate_Block_With_Init_Stmts 159 (Actions : List_Id; 160 N : Node_Id; 161 Init_Stmts : List_Id); 162 -- Ada 2005 (AI-287): Similar to previous routine, but used to expand 163 -- allocated aggregates with default initialized components. Init_Stmts 164 -- contains the list of statements required to initialize the allocated 165 -- aggregate. It replaces the call to Init (Args) done by 166 -- Build_Task_Allocate_Block. Also used to expand allocators containing 167 -- build-in-place function calls. 168 169 function Build_Wrapper_Spec 170 (Subp_Id : Entity_Id; 171 Obj_Typ : Entity_Id; 172 Formals : List_Id) return Node_Id; 173 -- Ada 2005 (AI-345): Build the specification of a primitive operation 174 -- associated with a protected or task type. This is required to implement 175 -- dispatching calls through interfaces. Subp_Id is the primitive to be 176 -- wrapped, Obj_Typ is the type of the newly added formal parameter to 177 -- handle object notation, Formals are the original entry formals that 178 -- will be explicitly replicated. 179 180 function Concurrent_Ref (N : Node_Id) return Node_Id; 181 -- Given the name of a concurrent object (task or protected object), or 182 -- the name of an access to a concurrent object, this function returns an 183 -- expression referencing the associated Task_Id or Protection object, 184 -- respectively. Note that a special case is when the name is a reference 185 -- to a task type name. This can only happen within a task body, and the 186 -- meaning is to get the Task_Id for the currently executing task. 187 188 function Convert_Concurrent 189 (N : Node_Id; 190 Typ : Entity_Id) return Node_Id; 191 -- N is an expression of type Typ. If the type is not a concurrent type 192 -- then it is returned unchanged. If it is a task or protected reference, 193 -- Convert_Concurrent creates an unchecked conversion node from this 194 -- expression to the corresponding concurrent record type value. We need 195 -- this in any situation where the concurrent type is used, because the 196 -- actual concurrent object is an object of the corresponding concurrent 197 -- type, and manipulations on the concurrent object actually manipulate the 198 -- corresponding object of the record type. 199 200 function Entry_Index_Expression 201 (Sloc : Source_Ptr; 202 Ent : Entity_Id; 203 Index : Node_Id; 204 Ttyp : Entity_Id) 205 return Node_Id; 206 -- Returns an expression to compute a task entry index given the name of 207 -- the entry or entry family. For the case of a task entry family, the 208 -- Index parameter contains the expression for the subscript. Ttyp is the 209 -- task type. 210 211 procedure Establish_Task_Master (N : Node_Id); 212 -- Given a subprogram body, or a block statement, or a task body, this 213 -- procedure makes the necessary transformations required of a task master 214 -- (add Enter_Master call at start, and establish a cleanup routine to make 215 -- sure Complete_Master is called on exit). 216 217 procedure Expand_Access_Protected_Subprogram_Type (N : Node_Id); 218 -- Build Equivalent_Type for an Access_To_Protected_Subprogram. 219 -- Equivalent_Type is a record type with two components: a pointer to the 220 -- protected object, and a pointer to the operation itself. 221 222 procedure Expand_Accept_Declarations (N : Node_Id; Ent : Entity_Id); 223 -- Expand declarations required for accept statement. See bodies of both 224 -- Expand_Accept_Declarations and Expand_N_Accept_Statement for full 225 -- details of the nature and use of these declarations, which are inserted 226 -- immediately before the accept node N. The second argument is the entity 227 -- for the corresponding entry. 228 229 procedure Expand_Entry_Barrier (N : Node_Id; Ent : Entity_Id); 230 -- Expand the entry barrier into a function. This is called directly 231 -- from Analyze_Entry_Body so that the discriminals and privals of the 232 -- barrier can be attached to the function declaration list, and a new 233 -- set prepared for the entry body procedure, before the entry body 234 -- statement sequence can be expanded. The resulting function is analyzed 235 -- now, within the context of the protected object, to resolve calls to 236 -- other protected functions. 237 238 procedure Expand_N_Abort_Statement (N : Node_Id); 239 procedure Expand_N_Accept_Statement (N : Node_Id); 240 procedure Expand_N_Asynchronous_Select (N : Node_Id); 241 procedure Expand_N_Conditional_Entry_Call (N : Node_Id); 242 procedure Expand_N_Delay_Relative_Statement (N : Node_Id); 243 procedure Expand_N_Delay_Until_Statement (N : Node_Id); 244 procedure Expand_N_Entry_Body (N : Node_Id); 245 procedure Expand_N_Entry_Call_Statement (N : Node_Id); 246 procedure Expand_N_Entry_Declaration (N : Node_Id); 247 procedure Expand_N_Protected_Body (N : Node_Id); 248 249 procedure Expand_N_Protected_Type_Declaration (N : Node_Id); 250 -- Expands protected type declarations. This results, among other things, 251 -- in the declaration of a record type for the representation of protected 252 -- objects and (if there are entries) in an entry service procedure. The 253 -- Protection value used by the GNARL to control the object will always be 254 -- the first field of the record, and the entry service procedure spec (if 255 -- it exists) will always immediately follow the record declaration. This 256 -- allows these two nodes to be found from the type, without benefit of 257 -- further attributes, using Corresponding_Record. 258 259 procedure Expand_N_Requeue_Statement (N : Node_Id); 260 procedure Expand_N_Selective_Accept (N : Node_Id); 261 procedure Expand_N_Single_Protected_Declaration (N : Node_Id); 262 procedure Expand_N_Single_Task_Declaration (N : Node_Id); 263 procedure Expand_N_Task_Body (N : Node_Id); 264 procedure Expand_N_Task_Type_Declaration (N : Node_Id); 265 procedure Expand_N_Timed_Entry_Call (N : Node_Id); 266 267 procedure Expand_Protected_Body_Declarations 268 (N : Node_Id; 269 Spec_Id : Entity_Id); 270 -- Expand declarations required for a protected body. See bodies of both 271 -- Expand_Protected_Body_Declarations and Expand_N_Protected_Body for full 272 -- details of the nature and use of these declarations. The second argument 273 -- is the entity for the corresponding protected type declaration. 274 275 function External_Subprogram (E : Entity_Id) return Entity_Id; 276 -- Return the external version of a protected operation, which locks 277 -- the object before invoking the internal protected subprogram body. 278 279 function Find_Master_Scope (E : Entity_Id) return Entity_Id; 280 -- When a type includes tasks, a master entity is created in the scope, to 281 -- be used by the runtime during activation. In general the master is the 282 -- immediate scope in which the type is declared, but in Ada 2005, in the 283 -- presence of synchronized classwide interfaces, the immediate scope of 284 -- an anonymous access type may be a transient scope, which has no run-time 285 -- presence. In this case, the scope of the master is the innermost scope 286 -- that comes from source. 287 288 function First_Protected_Operation (D : List_Id) return Node_Id; 289 -- Given the declarations list for a protected body, find the 290 -- first protected operation body. 291 292 procedure Install_Private_Data_Declarations 293 (Loc : Source_Ptr; 294 Spec_Id : Entity_Id; 295 Conc_Typ : Entity_Id; 296 Body_Nod : Node_Id; 297 Decls : List_Id; 298 Barrier : Boolean := False; 299 Family : Boolean := False); 300 -- This routines generates several types, objects and object renamings used 301 -- in the handling of discriminants and private components of protected and 302 -- task types. It also generates the entry index for entry families. Formal 303 -- Spec_Id denotes an entry, entry family or a subprogram, Conc_Typ is the 304 -- concurrent type where Spec_Id resides, Body_Nod is the corresponding 305 -- body of Spec_Id, Decls are the declarations of the subprogram or entry. 306 -- Flag Barrier denotes whether the context is an entry barrier function. 307 -- Flag Family is used in conjunction with Barrier to denote a barrier for 308 -- an entry family. 309 -- 310 -- The generated types, entities and renamings are: 311 -- 312 -- * If flag Barrier is set or Spec_Id denotes a protected entry or an 313 -- entry family, generate: 314 -- 315 -- type prot_typVP is access prot_typV; 316 -- _object : prot_typVP := prot_typV (_O); 317 -- 318 -- where prot_typV is the corresponding record of a protected type and 319 -- _O is a formal parameter representing the concurrent object of either 320 -- the barrier function or the entry (family). 321 -- 322 -- * If Conc_Typ is a protected type, create a renaming for the Protection 323 -- field _object: 324 -- 325 -- conc_typR : protection_typ renames _object._object; 326 -- 327 -- * If Conc_Typ has discriminants, create renamings of the form: 328 -- 329 -- discr_nameD : discr_typ renames _object.discr_name; 330 -- or 331 -- discr_nameD : discr_typ renames _task.discr_name; 332 -- 333 -- * If Conc_Typ denotes a protected type and has private components, 334 -- generate renamings of the form: 335 -- 336 -- comp_name : comp_typ renames _object.comp_name; 337 -- 338 -- * Finally, is flag Barrier and Family are set or Spec_Id denotes an 339 -- entry family, generate the entry index constant: 340 -- 341 -- subtype Jnn is <Type of Index> range Low .. High; 342 -- J : constant Jnn := 343 -- Jnn'Val (_E - <Index expression> + Jnn'Pos (Jnn'First)); 344 -- 345 -- All the above declarations are inserted in the order shown to the front 346 -- of Decls. 347 348 function Make_Task_Create_Call (Task_Rec : Entity_Id) return Node_Id; 349 -- Given the entity of the record type created for a task type, build 350 -- the call to Create_Task 351 352 function Make_Initialize_Protection 353 (Protect_Rec : Entity_Id) return List_Id; 354 -- Given the entity of the record type created for a protected type, build 355 -- a list of statements needed for proper initialization of the object. 356 357 function Next_Protected_Operation (N : Node_Id) return Node_Id; 358 -- Given a protected operation node (a subprogram or entry body), find the 359 -- following node in the declarations list. 360 361 procedure Set_Discriminals (Dec : Node_Id); 362 -- Replace discriminals in a protected type for use by the next protected 363 -- operation on the type. Each operation needs a new set of discriminals, 364 -- since it needs a unique renaming of the discriminant fields in the 365 -- record used to implement the protected type. 366 367end Exp_Ch9; 368