1------------------------------------------------------------------------------ 2-- -- 3-- GNAT COMPILER COMPONENTS -- 4-- -- 5-- E X P _ C H 9 -- 6-- -- 7-- S p e c -- 8-- -- 9-- Copyright (C) 1992-2020, 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 function Build_Master_Declaration (Loc : Source_Ptr) return Node_Id; 59 -- For targets supporting tasks, generate: 60 -- _Master : constant Integer := Current_Master.all; 61 -- For targets where tasks or tasking hierarchies are prohibited, generate: 62 -- _Master : constant Master_Id := 3; 63 64 procedure Build_Master_Entity (Obj_Or_Typ : Entity_Id); 65 -- Given the name of an object or a type which is either a task, contains 66 -- tasks or designates tasks, create a _master in the appropriate scope 67 -- which captures the value of Current_Master. Mark the nearest enclosing 68 -- body or block as being a task master. 69 70 procedure Build_Master_Renaming 71 (Ptr_Typ : Entity_Id; 72 Ins_Nod : Node_Id := Empty); 73 -- Given an access type Ptr_Typ whose designated type is either a task or 74 -- contains tasks, create a renaming of the form: 75 -- 76 -- <Ptr_Typ>M : Master_Id renames _Master; 77 -- 78 -- where _master denotes the task master of the enclosing context. Ins_Nod 79 -- is used to provide a specific insertion node for the renaming. 80 81 function Build_Protected_Sub_Specification 82 (N : Node_Id; 83 Prot_Typ : Entity_Id; 84 Mode : Subprogram_Protection_Mode) return Node_Id; 85 -- Build the specification for protected subprogram. This is called when 86 -- expanding a protected type, and also when expanding the declaration for 87 -- an Access_To_Protected_Subprogram type. In the latter case, Prot_Typ is 88 -- empty, and the first parameter of the signature of the protected op is 89 -- of type System.Address. 90 91 procedure Build_Protected_Subprogram_Call 92 (N : Node_Id; 93 Name : Node_Id; 94 Rec : Node_Id; 95 External : Boolean := True); 96 -- The node N is a subprogram or entry call to a protected subprogram. This 97 -- procedure rewrites this call with the appropriate expansion. Name is the 98 -- subprogram, and Rec is the record corresponding to the protected object. 99 -- External is False if the call is to another protected subprogram within 100 -- the same object. 101 102 procedure Build_Protected_Subprogram_Call_Cleanup 103 (Op_Spec : Node_Id; 104 Conc_Typ : Node_Id; 105 Loc : Source_Ptr; 106 Stmts : List_Id); 107 -- Append to Stmts the cleanups after a call to a protected subprogram 108 -- whose specification is Op_Spec. Conc_Typ is the concurrent type and Loc 109 -- the sloc for appended statements. The cleanup will either unlock the 110 -- protected object or serve pending entries. 111 112 procedure Build_Task_Activation_Call (N : Node_Id); 113 -- This procedure is called for constructs that can be task activators, 114 -- i.e. task bodies, subprogram bodies, package bodies and blocks. If the 115 -- construct is a task activator (as indicated by the non-empty setting of 116 -- Activation_Chain_Entity, either in the construct, or, in the case of a 117 -- package body, in its associated package spec), then a call to 118 -- Activate_Tasks with this entity as the single parameter is inserted at 119 -- the start of the statements of the activator. 120 121 procedure Build_Task_Allocate_Block 122 (Actions : List_Id; 123 N : Node_Id; 124 Args : List_Id); 125 -- This routine is used in the case of allocators where the designated type 126 -- is a task or contains tasks. In this case, the normal initialize call 127 -- is replaced by: 128 -- 129 -- blockname : label; 130 -- blockname : declare 131 -- _Chain : Activation_Chain; 132 -- 133 -- procedure _Expunge is 134 -- begin 135 -- Expunge_Unactivated_Tasks (_Chain); 136 -- end; 137 -- 138 -- begin 139 -- Init (Args); 140 -- Activate_Tasks (_Chain); 141 -- at end 142 -- _Expunge; 143 -- end; 144 -- 145 -- to get the task or tasks created and initialized. The expunge call 146 -- ensures that any tasks that get created but not activated due to an 147 -- exception are properly expunged (it has no effect in the normal case). 148 -- The argument N is the allocator, and Args is the list of arguments for 149 -- the initialization call, constructed by the caller, which uses the 150 -- Master_Id of the access type as the _Master parameter, and _Chain 151 -- (defined above) as the _Chain parameter. 152 153 procedure Build_Task_Allocate_Block_With_Init_Stmts 154 (Actions : List_Id; 155 N : Node_Id; 156 Init_Stmts : List_Id); 157 -- Ada 2005 (AI-287): Similar to previous routine, but used to expand 158 -- allocated aggregates with default initialized components. Init_Stmts 159 -- contains the list of statements required to initialize the allocated 160 -- aggregate. It replaces the call to Init (Args) done by 161 -- Build_Task_Allocate_Block. Also used to expand allocators containing 162 -- build-in-place function calls. 163 164 function Build_Wrapper_Spec 165 (Subp_Id : Entity_Id; 166 Obj_Typ : Entity_Id; 167 Formals : List_Id) return Node_Id; 168 -- Ada 2005 (AI-345): Build the specification of a primitive operation 169 -- associated with a protected or task type. This is required to implement 170 -- dispatching calls through interfaces. Subp_Id is the primitive to be 171 -- wrapped, Obj_Typ is the type of the newly added formal parameter to 172 -- handle object notation, Formals are the original entry formals that 173 -- will be explicitly replicated. 174 175 function Concurrent_Ref (N : Node_Id) return Node_Id; 176 -- Given the name of a concurrent object (task or protected object), or 177 -- the name of an access to a concurrent object, this function returns an 178 -- expression referencing the associated Task_Id or Protection object, 179 -- respectively. Note that a special case is when the name is a reference 180 -- to a task type name. This can only happen within a task body, and the 181 -- meaning is to get the Task_Id for the currently executing task. 182 183 function Convert_Concurrent 184 (N : Node_Id; 185 Typ : Entity_Id) return Node_Id; 186 -- N is an expression of type Typ. If the type is not a concurrent type 187 -- then it is returned unchanged. If it is a task or protected reference, 188 -- Convert_Concurrent creates an unchecked conversion node from this 189 -- expression to the corresponding concurrent record type value. We need 190 -- this in any situation where the concurrent type is used, because the 191 -- actual concurrent object is an object of the corresponding concurrent 192 -- type, and manipulations on the concurrent object actually manipulate the 193 -- corresponding object of the record type. 194 195 function Entry_Index_Expression 196 (Sloc : Source_Ptr; 197 Ent : Entity_Id; 198 Index : Node_Id; 199 Ttyp : Entity_Id) 200 return Node_Id; 201 -- Returns an expression to compute a task entry index given the name of 202 -- the entry or entry family. For the case of a task entry family, the 203 -- Index parameter contains the expression for the subscript. Ttyp is the 204 -- task type. 205 206 procedure Establish_Task_Master (N : Node_Id); 207 -- Given a subprogram body, or a block statement, or a task body, this 208 -- procedure makes the necessary transformations required of a task master 209 -- (add Enter_Master call at start, and establish a cleanup routine to make 210 -- sure Complete_Master is called on exit). 211 212 procedure Expand_Access_Protected_Subprogram_Type (N : Node_Id); 213 -- Build Equivalent_Type for an Access_To_Protected_Subprogram. 214 -- Equivalent_Type is a record type with two components: a pointer to the 215 -- protected object, and a pointer to the operation itself. 216 217 procedure Expand_Accept_Declarations (N : Node_Id; Ent : Entity_Id); 218 -- Expand declarations required for accept statement. See bodies of both 219 -- Expand_Accept_Declarations and Expand_N_Accept_Statement for full 220 -- details of the nature and use of these declarations, which are inserted 221 -- immediately before the accept node N. The second argument is the entity 222 -- for the corresponding entry. 223 224 procedure Expand_Entry_Barrier (N : Node_Id; Ent : Entity_Id); 225 -- Expand the entry barrier into a function. This is called directly 226 -- from Analyze_Entry_Body so that the discriminals and privals of the 227 -- barrier can be attached to the function declaration list, and a new 228 -- set prepared for the entry body procedure, before the entry body 229 -- statement sequence can be expanded. The resulting function is analyzed 230 -- now, within the context of the protected object, to resolve calls to 231 -- other protected functions. 232 233 procedure Expand_N_Abort_Statement (N : Node_Id); 234 procedure Expand_N_Accept_Statement (N : Node_Id); 235 procedure Expand_N_Asynchronous_Select (N : Node_Id); 236 procedure Expand_N_Conditional_Entry_Call (N : Node_Id); 237 procedure Expand_N_Delay_Relative_Statement (N : Node_Id); 238 procedure Expand_N_Delay_Until_Statement (N : Node_Id); 239 procedure Expand_N_Entry_Body (N : Node_Id); 240 procedure Expand_N_Entry_Call_Statement (N : Node_Id); 241 procedure Expand_N_Entry_Declaration (N : Node_Id); 242 procedure Expand_N_Protected_Body (N : Node_Id); 243 244 procedure Expand_N_Protected_Type_Declaration (N : Node_Id); 245 -- Expands protected type declarations. This results, among other things, 246 -- in the declaration of a record type for the representation of protected 247 -- objects and (if there are entries) in an entry service procedure. The 248 -- Protection value used by the GNARL to control the object will always be 249 -- the first field of the record, and the entry service procedure spec (if 250 -- it exists) will always immediately follow the record declaration. This 251 -- allows these two nodes to be found from the type, without benefit of 252 -- further attributes, using Corresponding_Record. 253 254 procedure Expand_N_Requeue_Statement (N : Node_Id); 255 procedure Expand_N_Selective_Accept (N : Node_Id); 256 procedure Expand_N_Single_Protected_Declaration (N : Node_Id); 257 procedure Expand_N_Single_Task_Declaration (N : Node_Id); 258 procedure Expand_N_Task_Body (N : Node_Id); 259 procedure Expand_N_Task_Type_Declaration (N : Node_Id); 260 procedure Expand_N_Timed_Entry_Call (N : Node_Id); 261 262 procedure Expand_Protected_Body_Declarations 263 (N : Node_Id; 264 Spec_Id : Entity_Id); 265 -- Expand declarations required for a protected body. See bodies of both 266 -- Expand_Protected_Body_Declarations and Expand_N_Protected_Body for full 267 -- details of the nature and use of these declarations. The second argument 268 -- is the entity for the corresponding protected type declaration. 269 270 function External_Subprogram (E : Entity_Id) return Entity_Id; 271 -- Return the external version of a protected operation, which locks 272 -- the object before invoking the internal protected subprogram body. 273 274 function Find_Master_Scope (E : Entity_Id) return Entity_Id; 275 -- When a type includes tasks, a master entity is created in the scope, to 276 -- be used by the runtime during activation. In general the master is the 277 -- immediate scope in which the type is declared, but in Ada 2005, in the 278 -- presence of synchronized classwide interfaces, the immediate scope of 279 -- an anonymous access type may be a transient scope, which has no run-time 280 -- presence. In this case, the scope of the master is the innermost scope 281 -- that comes from source. 282 283 function First_Protected_Operation (D : List_Id) return Node_Id; 284 -- Given the declarations list for a protected body, find the 285 -- first protected operation body. 286 287 procedure Install_Private_Data_Declarations 288 (Loc : Source_Ptr; 289 Spec_Id : Entity_Id; 290 Conc_Typ : Entity_Id; 291 Body_Nod : Node_Id; 292 Decls : List_Id; 293 Barrier : Boolean := False; 294 Family : Boolean := False); 295 -- This routines generates several types, objects and object renamings used 296 -- in the handling of discriminants and private components of protected and 297 -- task types. It also generates the entry index for entry families. Formal 298 -- Spec_Id denotes an entry, entry family or a subprogram, Conc_Typ is the 299 -- concurrent type where Spec_Id resides, Body_Nod is the corresponding 300 -- body of Spec_Id, Decls are the declarations of the subprogram or entry. 301 -- Flag Barrier denotes whether the context is an entry barrier function. 302 -- Flag Family is used in conjunction with Barrier to denote a barrier for 303 -- an entry family. 304 -- 305 -- The generated types, entities and renamings are: 306 -- 307 -- * If flag Barrier is set or Spec_Id denotes a protected entry or an 308 -- entry family, generate: 309 -- 310 -- type prot_typVP is access prot_typV; 311 -- _object : prot_typVP := prot_typV (_O); 312 -- 313 -- where prot_typV is the corresponding record of a protected type and 314 -- _O is a formal parameter representing the concurrent object of either 315 -- the barrier function or the entry (family). 316 -- 317 -- * If Conc_Typ is a protected type, create a renaming for the Protection 318 -- field _object: 319 -- 320 -- conc_typR : protection_typ renames _object._object; 321 -- 322 -- * If Conc_Typ has discriminants, create renamings of the form: 323 -- 324 -- discr_nameD : discr_typ renames _object.discr_name; 325 -- or 326 -- discr_nameD : discr_typ renames _task.discr_name; 327 -- 328 -- * If Conc_Typ denotes a protected type and has private components, 329 -- generate renamings of the form: 330 -- 331 -- comp_name : comp_typ renames _object.comp_name; 332 -- 333 -- * Finally, is flag Barrier and Family are set or Spec_Id denotes an 334 -- entry family, generate the entry index constant: 335 -- 336 -- subtype Jnn is <Type of Index> range Low .. High; 337 -- J : constant Jnn := 338 -- Jnn'Val (_E - <Index expression> + Jnn'Pos (Jnn'First)); 339 -- 340 -- All the above declarations are inserted in the order shown to the front 341 -- of Decls. 342 343 function Make_Task_Create_Call (Task_Rec : Entity_Id) return Node_Id; 344 -- Given the entity of the record type created for a task type, build 345 -- the call to Create_Task 346 347 function Make_Initialize_Protection 348 (Protect_Rec : Entity_Id) return List_Id; 349 -- Given the entity of the record type created for a protected type, build 350 -- a list of statements needed for proper initialization of the object. 351 352 function Next_Protected_Operation (N : Node_Id) return Node_Id; 353 -- Given a protected operation node (a subprogram or entry body), find the 354 -- following node in the declarations list. 355 356 procedure Set_Discriminals (Dec : Node_Id); 357 -- Replace discriminals in a protected type for use by the next protected 358 -- operation on the type. Each operation needs a new set of discriminals, 359 -- since it needs a unique renaming of the discriminant fields in the 360 -- record used to implement the protected type. 361 362end Exp_Ch9; 363