funcnode.cc

   1 #include "action.h"
   2 #include "history.h"
   3 #include "funcnode.h"
   4 #include "funcinst.h"
   5 #include "predicate.h"
   6 #include "concretepredicate.h"
   7
   8 FuncNode::FuncNode(ModelHistory * history) :
   9         history(history),
  10         exit_count(0),
  11         func_inst_map(),
  12         inst_list(),
  13         entry_insts(),
  14         predicate_tree_position(),
  15         edge_table(32),
  16         out_edges()
  17 {
  18         predicate_tree_entry = new Predicate(NULL, true);
  19         predicate_tree_entry->add_predicate_expr(NOPREDICATE, NULL, true);
  20
  21         // Memories that are reclaimed after each execution
  22         action_list_buffer = new SnapList<action_list_t *>();
  23         read_locations = new loc_set_t();
  24         write_locations = new loc_set_t();
  25         val_loc_map = new HashTable<uint64_t, loc_set_t *, uint64_t, 0>();
  26         loc_may_equal_map = new HashTable<void *, loc_set_t *, uintptr_t, 0>();
  27         thrd_inst_act_map = new SnapVector<inst_act_map_t *>();
  28
  29         //values_may_read_from = new value_set_t();
  30 }
  31
  32 /* Reallocate snapshotted memories when new executions start */
  33 void FuncNode::set_new_exec_flag()
  34 {
  35         for (mllnode<FuncInst *> * it = inst_list.begin(); it != NULL; it = it->getNext()) {
  36                 FuncInst * inst = it->getVal();
  37                 inst->unset_location();
  38         }
  39
  40         action_list_buffer = new SnapList<action_list_t *>();
  41         read_locations = new loc_set_t();
  42         write_locations = new loc_set_t();
  43         val_loc_map = new HashTable<uint64_t, loc_set_t *, uint64_t, 0>();
  44         loc_may_equal_map = new HashTable<void *, loc_set_t *, uintptr_t, 0>();
  45         thrd_inst_act_map = new SnapVector<inst_act_map_t *>();
  46
  47         //values_may_read_from = new value_set_t();
  48 }
  49
  50 /* Check whether FuncInst with the same type, position, and location
  51  * as act has been added to func_inst_map or not. If not, add it.
  52  *
  53  * Note: currently, actions with the same position are filtered out by process_action,
  54  * so the collision list of FuncInst is not used. May remove it later.
  55  */
  56 void FuncNode::add_inst(ModelAction *act)
  57 {
  58         ASSERT(act);
  59         const char * position = act->get_position();
  60
  61         /* THREAD* actions, ATOMIC_LOCK, ATOMIC_TRYLOCK, and ATOMIC_UNLOCK
  62          * actions are not tagged with their source line numbers
  63          */
  64         if (position == NULL)
  65                 return;
  66
  67         if ( func_inst_map.contains(position) ) {
  68                 FuncInst * inst = func_inst_map.get(position);
  69
  70                 ASSERT(inst->get_type() == act->get_type());
  71
  72                 // locations are set to NULL when new executions start
  73                 if (inst->get_location() == NULL)
  74                         inst->set_location(act->get_location());
  75
  76                 if (inst->get_location() != act->get_location())
  77                         inst->not_single_location();
  78
  79                 return;
  80         }
  81
  82         FuncInst * func_inst = new FuncInst(act, this);
  83
  84         func_inst_map.put(position, func_inst);
  85         inst_list.push_back(func_inst);
  86 }
  87
  88 /* Get the FuncInst with the same type, position, and location
  89  * as act
  90  *
  91  * @return FuncInst with the same type, position, and location as act */
  92 FuncInst * FuncNode::get_inst(ModelAction *act)
  93 {
  94         ASSERT(act);
  95         const char * position = act->get_position();
  96
  97         /* THREAD* actions, ATOMIC_LOCK, ATOMIC_TRYLOCK, and ATOMIC_UNLOCK
  98          * actions are not tagged with their source line numbers
  99          */
 100         if (position == NULL)
 101                 return NULL;
 102
 103         FuncInst * inst = func_inst_map.get(position);
 104         if (inst == NULL)
 105                 return NULL;
 106
 107         action_type inst_type = inst->get_type();
 108         action_type act_type = act->get_type();
 109
 110         // else if branch: an RMWRCAS action is converted to a RMW or READ action
 111         if (inst_type == act_type)
 112                 return inst;
 113         else if (inst_type == ATOMIC_RMWRCAS &&
 114                         (act_type == ATOMIC_RMW || act_type == ATOMIC_READ))
 115                 return inst;
 116
 117         return NULL;
 118 }
 119
 120
 121 void FuncNode::add_entry_inst(FuncInst * inst)
 122 {
 123         if (inst == NULL)
 124                 return;
 125
 126         mllnode<FuncInst *> * it;
 127         for (it = entry_insts.begin(); it != NULL; it = it->getNext()) {
 128                 if (inst == it->getVal())
 129                         return;
 130         }
 131
 132         entry_insts.push_back(inst);
 133 }
 134
 135 /**
 136  * @brief Convert ModelAdtion list to FuncInst list
 137  * @param act_list A list of ModelActions
 138  */
 139 void FuncNode::update_tree(action_list_t * act_list)
 140 {
 141         if (act_list == NULL || act_list->size() == 0)
 142                 return;
 143
 144         HashTable<void *, value_set_t *, uintptr_t, 4> * write_history = history->getWriteHistory();
 145
 146         /* build inst_list from act_list for later processing */
 147         func_inst_list_t inst_list;
 148         action_list_t rw_act_list;
 149
 150         for (sllnode<ModelAction *> * it = act_list->begin(); it != NULL; it = it->getNext()) {
 151                 ModelAction * act = it->getVal();
 152                 FuncInst * func_inst = get_inst(act);
 153                 void * loc = act->get_location();
 154
 155                 if (func_inst == NULL)
 156                         continue;
 157
 158                 inst_list.push_back(func_inst);
 159                 bool act_added = false;
 160
 161                 if (act->is_write()) {
 162                         rw_act_list.push_back(act);
 163                         act_added = true;
 164                         if (!write_locations->contains(loc)) {
 165                                 write_locations->add(loc);
 166                                 history->update_loc_wr_func_nodes_map(loc, this);
 167                         }
 168
 169                 }
 170
 171                 if (act->is_read()) {
 172                         if (!act_added)
 173                                 rw_act_list.push_back(act);
 174
 175                         /* If func_inst may only read_from a single location, then:
 176                          *
 177                          * The first time an action reads from some location,
 178                          * import all the values that have been written to this
 179                          * location from ModelHistory and notify ModelHistory
 180                          * that this FuncNode may read from this location.
 181                          */
 182                         if (!read_locations->contains(loc) && func_inst->is_single_location()) {
 183                                 read_locations->add(loc);
 184                                 value_set_t * write_values = write_history->get(loc);
 185                                 add_to_val_loc_map(write_values, loc);
 186                                 history->update_loc_func_nodes_map(loc, this);
 187                         }
 188                 }
 189         }
 190
 191 //      model_print("function %s\n", func_name);
 192 //      print_val_loc_map();
 193
 194         update_inst_tree(&inst_list);
 195         update_predicate_tree(&rw_act_list);
 196
 197 //      print_predicate_tree();
 198 }
 199
 200 /**
 201  * @brief Link FuncInsts in inst_list  - add one FuncInst to another's predecessors and successors
 202  * @param inst_list A list of FuncInsts
 203  */
 204 void FuncNode::update_inst_tree(func_inst_list_t * inst_list)
 205 {
 206         if (inst_list == NULL)
 207                 return;
 208         else if (inst_list->size() == 0)
 209                 return;
 210
 211         /* start linking */
 212         sllnode<FuncInst *>* it = inst_list->begin();
 213         sllnode<FuncInst *>* prev;
 214
 215         /* add the first instruction to the list of entry insts */
 216         FuncInst * entry_inst = it->getVal();
 217         add_entry_inst(entry_inst);
 218
 219         it = it->getNext();
 220         while (it != NULL) {
 221                 prev = it->getPrev();
 222
 223                 FuncInst * prev_inst = prev->getVal();
 224                 FuncInst * curr_inst = it->getVal();
 225
 226                 prev_inst->add_succ(curr_inst);
 227                 curr_inst->add_pred(prev_inst);
 228
 229                 it = it->getNext();
 230         }
 231 }
 232
 233 void FuncNode::update_predicate_tree(action_list_t * act_list)
 234 {
 235         if (act_list == NULL || act_list->size() == 0)
 236                 return;
 237
 238         /* Map a FuncInst to the its predicate */
 239         HashTable<FuncInst *, Predicate *, uintptr_t, 0> inst_pred_map(128);
 240
 241         // Number FuncInsts to detect loops
 242         HashTable<FuncInst *, uint32_t, uintptr_t, 0> inst_id_map(128);
 243         uint32_t inst_counter = 0;
 244
 245         /* Only need to store the locations of read actions */
 246         HashTable<void *, ModelAction *, uintptr_t, 0> loc_act_map(128);
 247         HashTable<FuncInst *, ModelAction *, uintptr_t, 0> inst_act_map(128);
 248
 249         sllnode<ModelAction *> *it = act_list->begin();
 250         Predicate * curr_pred = predicate_tree_entry;
 251         while (it != NULL) {
 252                 ModelAction * next_act = it->getVal();
 253                 FuncInst * next_inst = get_inst(next_act);
 254
 255                 SnapVector<Predicate *> unset_predicates = SnapVector<Predicate *>();
 256                 bool branch_found = follow_branch(&curr_pred, next_inst, next_act, &inst_act_map, &unset_predicates);
 257
 258                 // A branch with unset predicate expression is detected
 259                 if (!branch_found && unset_predicates.size() != 0) {
 260                         ASSERT(unset_predicates.size() == 1);
 261                         Predicate * one_branch = unset_predicates[0];
 262
 263                         bool amended = amend_predicate_expr(&curr_pred, next_inst, next_act);
 264                         if (amended)
 265                                 continue;
 266                         else {
 267                                 curr_pred = one_branch;
 268                                 branch_found = true;
 269                         }
 270                 }
 271
 272                 // Detect loops
 273                 if (!branch_found && inst_id_map.contains(next_inst)) {
 274                         FuncInst * curr_inst = curr_pred->get_func_inst();
 275                         uint32_t curr_id = inst_id_map.get(curr_inst);
 276                         uint32_t next_id = inst_id_map.get(next_inst);
 277
 278                         if (curr_id >= next_id) {
 279                                 Predicate * old_pred = inst_pred_map.get(next_inst);
 280                                 Predicate * back_pred = old_pred->get_parent();
 281
 282                                 curr_pred->add_backedge(back_pred);
 283                                 curr_pred = back_pred;
 284
 285                                 continue;
 286                         }
 287                 }
 288
 289                 // Generate new branches
 290                 if (!branch_found) {
 291                         SnapVector<struct half_pred_expr *> half_pred_expressions;
 292                         infer_predicates(next_inst, next_act, &loc_act_map, &half_pred_expressions);
 293                         generate_predicates(&curr_pred, next_inst, &half_pred_expressions);
 294                         continue;
 295                 }
 296
 297                 if (next_act->is_write())
 298                         curr_pred->set_write(true);
 299
 300                 if (next_act->is_read()) {
 301                         loc_act_map.put(next_act->get_location(), next_act);
 302                 }
 303
 304                 inst_act_map.put(next_inst, next_act);
 305                 inst_pred_map.put(next_inst, curr_pred);
 306                 if (!inst_id_map.contains(next_inst))
 307                         inst_id_map.put(next_inst, inst_counter++);
 308
 309                 it = it->getNext();
 310         }
 311 }
 312
 313 /* Given curr_pred and next_inst, find the branch following curr_pred that
 314  * contains next_inst and the correct predicate.
 315  * @return true if branch found, false otherwise.
 316  */
 317 bool FuncNode::follow_branch(Predicate ** curr_pred, FuncInst * next_inst, ModelAction * next_act,
 318         HashTable<FuncInst *, ModelAction *, uintptr_t, 0> * inst_act_map,
 319         SnapVector<Predicate *> * unset_predicates)
 320 {
 321         /* check if a branch with func_inst and corresponding predicate exists */
 322         bool branch_found = false;
 323         ModelVector<Predicate *> * branches = (*curr_pred)->get_children();
 324         for (uint i = 0; i < branches->size(); i++) {
 325                 Predicate * branch = (*branches)[i];
 326                 if (branch->get_func_inst() != next_inst)
 327                         continue;
 328
 329                 /* Check against predicate expressions */
 330                 bool predicate_correct = true;
 331                 PredExprSet * pred_expressions = branch->get_pred_expressions();
 332
 333                 /* Only read and rmw actions my have unset predicate expressions */
 334                 if (pred_expressions->getSize() == 0) {
 335                         predicate_correct = false;
 336                         unset_predicates->push_back(branch);
 337                 }
 338
 339                 ConcretePredicate * concrete_pred = branch->evaluate(inst_act_map, next_act->get_tid());
 340                 SnapVector<struct concrete_pred_expr> * concrete_exprs = concrete_pred->getExpressions();
 341                 for (uint i = 0; i < concrete_exprs->size(); i++) {
 342                         struct concrete_pred_expr concrete = (*concrete_exprs)[i];
 343                         uint64_t next_read;
 344                         bool equality;
 345
 346                         switch (concrete.token) {
 347                                 case NOPREDICATE:
 348                                         predicate_correct = true;
 349                                         break;
 350                                 case EQUALITY:
 351                                         next_read = next_act->get_reads_from_value();
 352                                         equality = (next_read == concrete.value);
 353                                         if (equality != concrete.equality)
 354                                                 predicate_correct = false;
 355                                         break;
 356                                 case NULLITY:
 357                                         next_read = next_act->get_reads_from_value();
 358                                         equality = ((void*)next_read == NULL);
 359                                         if (equality != concrete.equality)
 360                                                 predicate_correct = false;
 361                                         break;
 362                                 default:
 363                                         predicate_correct = false;
 364                                         model_print("unkown predicate token\n");
 365                                         break;
 366                         }
 367                 }
 368
 369                 if (predicate_correct) {
 370                         *curr_pred = branch;
 371                         branch_found = true;
 372                         break;
 373                 }
 374         }
 375
 376         return branch_found;
 377 }
 378
 379 /* Infer predicate expressions, which are generated in FuncNode::generate_predicates */
 380 void FuncNode::infer_predicates(FuncInst * next_inst, ModelAction * next_act,
 381         HashTable<void *, ModelAction *, uintptr_t, 0> * loc_act_map,
 382         SnapVector<struct half_pred_expr *> * half_pred_expressions)
 383 {
 384         void * loc = next_act->get_location();
 385
 386         if (next_inst->is_read()) {
 387                 /* read + rmw */
 388                 if ( loc_act_map->contains(loc) ) {
 389                         ModelAction * last_act = loc_act_map->get(loc);
 390                         FuncInst * last_inst = get_inst(last_act);
 391                         struct half_pred_expr * expression = new half_pred_expr(EQUALITY, last_inst);
 392                         half_pred_expressions->push_back(expression);
 393                 } else if ( next_inst->is_single_location() ){
 394                         loc_set_t * loc_may_equal = loc_may_equal_map->get(loc);
 395
 396                         if (loc_may_equal != NULL) {
 397                                 loc_set_iter * loc_it = loc_may_equal->iterator();
 398                                 while (loc_it->hasNext()) {
 399                                         void * neighbor = loc_it->next();
 400                                         if (loc_act_map->contains(neighbor)) {
 401                                                 ModelAction * last_act = loc_act_map->get(neighbor);
 402                                                 FuncInst * last_inst = get_inst(last_act);
 403
 404                                                 struct half_pred_expr * expression = new half_pred_expr(EQUALITY, last_inst);
 405                                                 half_pred_expressions->push_back(expression);
 406                                         }
 407                                 }
 408                         }
 409                 } else {
 410                         // next_inst is not single location
 411                         uint64_t read_val = next_act->get_reads_from_value();
 412
 413                         // only infer NULLITY predicate when it is actually NULL.
 414                         if ( (void*)read_val == NULL) {
 415                                 struct half_pred_expr * expression = new half_pred_expr(NULLITY, NULL);
 416                                 half_pred_expressions->push_back(expression);
 417                         }
 418                 }
 419         } else {
 420                 /* Pure writes */
 421                 // TODO: do anything here?
 422         }
 423 }
 424
 425 /* Able to generate complex predicates when there are multiple predciate expressions */
 426 void FuncNode::generate_predicates(Predicate ** curr_pred, FuncInst * next_inst,
 427         SnapVector<struct half_pred_expr *> * half_pred_expressions)
 428 {
 429         if (half_pred_expressions->size() == 0) {
 430                 Predicate * new_pred = new Predicate(next_inst);
 431                 (*curr_pred)->add_child(new_pred);
 432                 new_pred->set_parent(*curr_pred);
 433
 434                 /* entry predicates and predicates containing pure write actions
 435                  * have no predicate expressions */
 436                 if ( (*curr_pred)->is_entry_predicate() )
 437                         new_pred->add_predicate_expr(NOPREDICATE, NULL, true);
 438                 else if (next_inst->is_write()) {
 439                         /* next_inst->is_write() <==> pure writes */
 440                         new_pred->add_predicate_expr(NOPREDICATE, NULL, true);
 441                 }
 442
 443                 return;
 444         }
 445
 446         SnapVector<Predicate *> predicates;
 447
 448         struct half_pred_expr * half_expr = (*half_pred_expressions)[0];
 449         predicates.push_back(new Predicate(next_inst));
 450         predicates.push_back(new Predicate(next_inst));
 451
 452         predicates[0]->add_predicate_expr(half_expr->token, half_expr->func_inst, true);
 453         predicates[1]->add_predicate_expr(half_expr->token, half_expr->func_inst, false);
 454
 455         for (uint i = 1; i < half_pred_expressions->size(); i++) {
 456                 half_expr = (*half_pred_expressions)[i];
 457
 458                 uint old_size = predicates.size();
 459                 for (uint j = 0; j < old_size; j++) {
 460                         Predicate * pred = predicates[j];
 461                         Predicate * new_pred = new Predicate(next_inst);
 462                         new_pred->copy_predicate_expr(pred);
 463
 464                         pred->add_predicate_expr(half_expr->token, half_expr->func_inst, true);
 465                         new_pred->add_predicate_expr(half_expr->token, half_expr->func_inst, false);
 466
 467                         predicates.push_back(new_pred);
 468                 }
 469         }
 470
 471         for (uint i = 0; i < predicates.size(); i++) {
 472                 Predicate * pred= predicates[i];
 473                 (*curr_pred)->add_child(pred);
 474                 pred->set_parent(*curr_pred);
 475         }
 476
 477         /* Free memories allocated by infer_predicate */
 478         for (uint i = 0; i < half_pred_expressions->size(); i++) {
 479                 struct half_pred_expr * tmp = (*half_pred_expressions)[i];
 480                 snapshot_free(tmp);
 481         }
 482 }
 483
 484 /* Amend predicates that contain no predicate expressions. Currenlty only amend with NULLITY predicates */
 485 bool FuncNode::amend_predicate_expr(Predicate ** curr_pred, FuncInst * next_inst, ModelAction * next_act)
 486 {
 487         // there should only be only child
 488         Predicate * unset_pred = (*curr_pred)->get_children()->back();
 489         uint64_t read_val = next_act->get_reads_from_value();
 490
 491         // only generate NULLITY predicate when it is actually NULL.
 492         if ( !next_inst->is_single_location() && (void*)read_val == NULL ) {
 493                 Predicate * new_pred = new Predicate(next_inst);
 494
 495                 (*curr_pred)->add_child(new_pred);
 496                 new_pred->set_parent(*curr_pred);
 497
 498                 unset_pred->add_predicate_expr(NULLITY, NULL, false);
 499                 new_pred->add_predicate_expr(NULLITY, NULL, true);
 500
 501                 return true;
 502         }
 503
 504         return false;
 505 }
 506
 507 void FuncNode::add_to_val_loc_map(uint64_t val, void * loc)
 508 {
 509         loc_set_t * locations = val_loc_map->get(val);
 510
 511         if (locations == NULL) {
 512                 locations = new loc_set_t();
 513                 val_loc_map->put(val, locations);
 514         }
 515
 516         update_loc_may_equal_map(loc, locations);
 517         locations->add(loc);
 518         // values_may_read_from->add(val);
 519 }
 520
 521 void FuncNode::add_to_val_loc_map(value_set_t * values, void * loc)
 522 {
 523         if (values == NULL)
 524                 return;
 525
 526         value_set_iter * it = values->iterator();
 527         while (it->hasNext()) {
 528                 uint64_t val = it->next();
 529                 add_to_val_loc_map(val, loc);
 530         }
 531 }
 532
 533 void FuncNode::update_loc_may_equal_map(void * new_loc, loc_set_t * old_locations)
 534 {
 535         if ( old_locations->contains(new_loc) )
 536                 return;
 537
 538         loc_set_t * neighbors = loc_may_equal_map->get(new_loc);
 539
 540         if (neighbors == NULL) {
 541                 neighbors = new loc_set_t();
 542                 loc_may_equal_map->put(new_loc, neighbors);
 543         }
 544
 545         loc_set_iter * loc_it = old_locations->iterator();
 546         while (loc_it->hasNext()) {
 547                 // new_loc: { old_locations, ... }
 548                 void * member = loc_it->next();
 549                 neighbors->add(member);
 550
 551                 // for each i in old_locations, i : { new_loc, ... }
 552                 loc_set_t * _neighbors = loc_may_equal_map->get(member);
 553                 if (_neighbors == NULL) {
 554                         _neighbors = new loc_set_t();
 555                         loc_may_equal_map->put(member, _neighbors);
 556                 }
 557                 _neighbors->add(new_loc);
 558         }
 559 }
 560
 561 /* Every time a thread enters a function, set its position to the predicate tree entry */
 562 void FuncNode::init_predicate_tree_position(thread_id_t tid)
 563 {
 564         int thread_id = id_to_int(tid);
 565         if (predicate_tree_position.size() <= (uint) thread_id)
 566                 predicate_tree_position.resize(thread_id + 1);
 567
 568         predicate_tree_position[thread_id] = predicate_tree_entry;
 569 }
 570
 571 void FuncNode::set_predicate_tree_position(thread_id_t tid, Predicate * pred)
 572 {
 573         int thread_id = id_to_int(tid);
 574         predicate_tree_position[thread_id] = pred;
 575 }
 576
 577 /* @return The position of a thread in a predicate tree */
 578 Predicate * FuncNode::get_predicate_tree_position(thread_id_t tid)
 579 {
 580         int thread_id = id_to_int(tid);
 581         return predicate_tree_position[thread_id];
 582 }
 583
 584 /* Make sure elements of thrd_inst_act_map are initialized properly when threads enter functions */
 585 void FuncNode::init_inst_act_map(thread_id_t tid)
 586 {
 587         int thread_id = id_to_int(tid);
 588         uint old_size = thrd_inst_act_map->size();
 589
 590         if (thrd_inst_act_map->size() <= (uint) thread_id) {
 591                 uint new_size = thread_id + 1;
 592                 thrd_inst_act_map->resize(new_size);
 593
 594                 for (uint i = old_size; i < new_size; i++)
 595                         (*thrd_inst_act_map)[i] = new inst_act_map_t(128);
 596         }
 597 }
 598
 599 /* Reset elements of thrd_inst_act_map when threads exit functions */
 600 void FuncNode::reset_inst_act_map(thread_id_t tid)
 601 {
 602         int thread_id = id_to_int(tid);
 603         inst_act_map_t * map = (*thrd_inst_act_map)[thread_id];
 604         map->reset();
 605 }
 606
 607 void FuncNode::update_inst_act_map(thread_id_t tid, ModelAction * read_act)
 608 {
 609         int thread_id = id_to_int(tid);
 610         inst_act_map_t * map = (*thrd_inst_act_map)[thread_id];
 611         FuncInst * read_inst = get_inst(read_act);
 612         map->put(read_inst, read_act);
 613 }
 614
 615 inst_act_map_t * FuncNode::get_inst_act_map(thread_id_t tid)
 616 {
 617         int thread_id = id_to_int(tid);
 618         return (*thrd_inst_act_map)[thread_id];
 619 }
 620
 621 /* Add FuncNodes that this node may follow */
 622 void FuncNode::add_out_edge(FuncNode * other)
 623 {
 624         if ( !edge_table.contains(other) ) {
 625                 edge_table.put(other, OUT_EDGE);
 626                 out_edges.push_back(other);
 627                 return;
 628         }
 629
 630         edge_type_t edge = edge_table.get(other);
 631         if (edge == IN_EDGE) {
 632                 edge_table.put(other, BI_EDGE);
 633                 out_edges.push_back(other);
 634         }
 635 }
 636
 637 void FuncNode::print_predicate_tree()
 638 {
 639         model_print("digraph function_%s {\n", func_name);
 640         predicate_tree_entry->print_pred_subtree();
 641         model_print("}\n");     // end of graph
 642 }
 643
 644 void FuncNode::print_val_loc_map()
 645 {
 646 /*
 647         value_set_iter * val_it = values_may_read_from->iterator();
 648         while (val_it->hasNext()) {
 649                 uint64_t value = val_it->next();
 650                 model_print("val %llx: ", value);
 651
 652                 loc_set_t * locations = val_loc_map->get(value);
 653                 loc_set_iter * loc_it = locations->iterator();
 654                 while (loc_it->hasNext()) {
 655                         void * location = loc_it->next();
 656                         model_print("%p ", location);
 657                 }
 658                 model_print("\n");
 659         }
 660 */
 661 }