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 #include "model.h"
   9 #include <cmath>
  10
  11 FuncNode::FuncNode(ModelHistory * history) :
  12         history(history),
  13         exit_count(0),
  14         marker(1),
  15         func_inst_map(),
  16         inst_list(),
  17         entry_insts(),
  18         inst_pred_map(128),
  19         inst_id_map(128),
  20         loc_act_map(128),
  21         predicate_tree_position(),
  22         predicate_leaves(),
  23         leaves_tmp_storage(),
  24         weight_debug_vec(),
  25         failed_predicates(),
  26         edge_table(32),
  27         out_edges()
  28 {
  29         predicate_tree_entry = new Predicate(NULL, true);
  30         predicate_tree_entry->add_predicate_expr(NOPREDICATE, NULL, true);
  31
  32         predicate_tree_exit = new Predicate(NULL, false, true);
  33         predicate_tree_exit->set_depth(MAX_DEPTH);
  34
  35         /* Snapshot data structures below */
  36         action_list_buffer = new SnapList<action_list_t *>();
  37         read_locations = new loc_set_t();
  38         write_locations = new loc_set_t();
  39         val_loc_map = new HashTable<uint64_t, loc_set_t *, uint64_t, 0, snapshot_malloc, snapshot_calloc, snapshot_free, int64_hash>();
  40         loc_may_equal_map = new HashTable<void *, loc_set_t *, uintptr_t, 0>();
  41
  42         //values_may_read_from = new value_set_t();
  43 }
  44
  45 /* Reallocate snapshotted memories when new executions start */
  46 void FuncNode::set_new_exec_flag()
  47 {
  48         action_list_buffer = new SnapList<action_list_t *>();
  49         read_locations = new loc_set_t();
  50         write_locations = new loc_set_t();
  51         val_loc_map = new HashTable<uint64_t, loc_set_t *, uint64_t, 0, snapshot_malloc, snapshot_calloc, snapshot_free, int64_hash>();
  52         loc_may_equal_map = new HashTable<void *, loc_set_t *, uintptr_t, 0>();
  53
  54         //values_may_read_from = new value_set_t();
  55 }
  56
  57 /* Check whether FuncInst with the same type, position, and location
  58  * as act has been added to func_inst_map or not. If not, add it.
  59  */
  60 void FuncNode::add_inst(ModelAction *act)
  61 {
  62         ASSERT(act);
  63         const char * position = act->get_position();
  64
  65         /* THREAD* actions, ATOMIC_LOCK, ATOMIC_TRYLOCK, and ATOMIC_UNLOCK
  66          * actions are not tagged with their source line numbers
  67          */
  68         if (position == NULL)
  69                 return;
  70
  71         FuncInst * func_inst = func_inst_map.get(position);
  72
  73         /* This position has not been inserted into hashtable before */
  74         if (func_inst == NULL) {
  75                 func_inst = create_new_inst(act);
  76                 func_inst_map.put(position, func_inst);
  77                 return;
  78         }
  79
  80         /* Volatile variables that use ++ or -- syntax may result in read and write actions with the same position */
  81         if (func_inst->get_type() != act->get_type()) {
  82                 FuncInst * collision_inst = func_inst->search_in_collision(act);
  83
  84                 if (collision_inst == NULL) {
  85                         collision_inst = create_new_inst(act);
  86                         func_inst->add_to_collision(collision_inst);
  87                         return;
  88                 } else {
  89                         func_inst = collision_inst;
  90                 }
  91         }
  92
  93         ASSERT(func_inst->get_type() == act->get_type());
  94         int curr_execution_number = model->get_execution_number();
  95
  96         /* Reset locations when new executions start */
  97         if (func_inst->get_execution_number() != curr_execution_number) {
  98                 func_inst->set_location(act->get_location());
  99                 func_inst->set_execution_number(curr_execution_number);
 100         }
 101
 102         /* Mark the memory location of such inst as not unique */
 103         if (func_inst->get_location() != act->get_location())
 104                 func_inst->not_single_location();
 105 }
 106
 107 FuncInst * FuncNode::create_new_inst(ModelAction * act)
 108 {
 109         FuncInst * func_inst = new FuncInst(act, this);
 110         int exec_num = model->get_execution_number();
 111         func_inst->set_execution_number(exec_num);
 112
 113         inst_list.push_back(func_inst);
 114
 115         return func_inst;
 116 }
 117
 118
 119 /* Get the FuncInst with the same type, position, and location
 120  * as act
 121  *
 122  * @return FuncInst with the same type, position, and location as act */
 123 FuncInst * FuncNode::get_inst(ModelAction *act)
 124 {
 125         ASSERT(act);
 126         const char * position = act->get_position();
 127
 128         /* THREAD* actions, ATOMIC_LOCK, ATOMIC_TRYLOCK, and ATOMIC_UNLOCK
 129          * actions are not tagged with their source line numbers
 130          */
 131         if (position == NULL)
 132                 return NULL;
 133
 134         FuncInst * inst = func_inst_map.get(position);
 135         if (inst == NULL)
 136                 return NULL;
 137
 138         action_type inst_type = inst->get_type();
 139         action_type act_type = act->get_type();
 140
 141         if (inst_type == act_type) {
 142                 return inst;
 143         }
 144         /* RMWRCAS actions are converted to RMW or READ actions */
 145         else if (inst_type == ATOMIC_RMWRCAS &&
 146                                          (act_type == ATOMIC_RMW || act_type == ATOMIC_READ)) {
 147                 return inst;
 148         }
 149         /* Return the FuncInst in the collision list */
 150         else {
 151                 return inst->search_in_collision(act);
 152         }
 153 }
 154
 155
 156 void FuncNode::add_entry_inst(FuncInst * inst)
 157 {
 158         if (inst == NULL)
 159                 return;
 160
 161         mllnode<FuncInst *> * it;
 162         for (it = entry_insts.begin();it != NULL;it = it->getNext()) {
 163                 if (inst == it->getVal())
 164                         return;
 165         }
 166
 167         entry_insts.push_back(inst);
 168 }
 169
 170 /**
 171  * @brief Convert ModelAdtion list to FuncInst list
 172  * @param act_list A list of ModelActions
 173  */
 174 void FuncNode::update_tree(action_list_t * act_list)
 175 {
 176         if (act_list == NULL || act_list->size() == 0)
 177                 return;
 178
 179         HashTable<void *, value_set_t *, uintptr_t, 0> * write_history = history->getWriteHistory();
 180
 181         /* build inst_list from act_list for later processing */
 182         func_inst_list_t inst_list;
 183         action_list_t rw_act_list;
 184
 185         for (sllnode<ModelAction *> * it = act_list->begin();it != NULL;it = it->getNext()) {
 186                 ModelAction * act = it->getVal();
 187                 FuncInst * func_inst = get_inst(act);
 188                 void * loc = act->get_location();
 189
 190                 if (func_inst == NULL)
 191                         continue;
 192
 193                 inst_list.push_back(func_inst);
 194                 bool act_added = false;
 195
 196                 if (act->is_write()) {
 197                         rw_act_list.push_back(act);
 198                         act_added = true;
 199                         if (!write_locations->contains(loc)) {
 200                                 write_locations->add(loc);
 201                                 history->update_loc_wr_func_nodes_map(loc, this);
 202                         }
 203                 }
 204
 205                 if (act->is_read()) {
 206                         if (!act_added)
 207                                 rw_act_list.push_back(act);
 208
 209                         /* If func_inst may only read_from a single location, then:
 210                          *
 211                          * The first time an action reads from some location,
 212                          * import all the values that have been written to this
 213                          * location from ModelHistory and notify ModelHistory
 214                          * that this FuncNode may read from this location.
 215                          */
 216                         if (!read_locations->contains(loc) && func_inst->is_single_location()) {
 217                                 read_locations->add(loc);
 218                                 value_set_t * write_values = write_history->get(loc);
 219                                 add_to_val_loc_map(write_values, loc);
 220                                 history->update_loc_rd_func_nodes_map(loc, this);
 221                         }
 222                 }
 223         }
 224
 225 //      model_print("function %s\n", func_name);
 226 //      print_val_loc_map();
 227
 228         update_inst_tree(&inst_list);
 229         update_predicate_tree(&rw_act_list);
 230
 231 //      print_predicate_tree();
 232 }
 233
 234 /**
 235  * @brief Link FuncInsts in inst_list  - add one FuncInst to another's predecessors and successors
 236  * @param inst_list A list of FuncInsts
 237  */
 238 void FuncNode::update_inst_tree(func_inst_list_t * inst_list)
 239 {
 240         if (inst_list == NULL)
 241                 return;
 242         else if (inst_list->size() == 0)
 243                 return;
 244
 245         /* start linking */
 246         sllnode<FuncInst *>* it = inst_list->begin();
 247         sllnode<FuncInst *>* prev;
 248
 249         /* add the first instruction to the list of entry insts */
 250         FuncInst * entry_inst = it->getVal();
 251         add_entry_inst(entry_inst);
 252
 253         it = it->getNext();
 254         while (it != NULL) {
 255                 prev = it->getPrev();
 256
 257                 FuncInst * prev_inst = prev->getVal();
 258                 FuncInst * curr_inst = it->getVal();
 259
 260                 prev_inst->add_succ(curr_inst);
 261                 curr_inst->add_pred(prev_inst);
 262
 263                 it = it->getNext();
 264         }
 265 }
 266
 267 void FuncNode::update_predicate_tree(action_list_t * act_list)
 268 {
 269         if (act_list == NULL || act_list->size() == 0)
 270                 return;
 271
 272         incr_marker();
 273         uint32_t inst_counter = 0;
 274
 275         // Clear hashtables
 276         loc_act_map.reset();
 277         inst_pred_map.reset();
 278         inst_id_map.reset();
 279
 280         // Clear the set of leaves encountered in this path
 281         leaves_tmp_storage.clear();
 282
 283         sllnode<ModelAction *> *it = act_list->begin();
 284         Predicate * curr_pred = predicate_tree_entry;
 285         while (it != NULL) {
 286                 ModelAction * next_act = it->getVal();
 287                 FuncInst * next_inst = get_inst(next_act);
 288                 next_inst->set_associated_act(next_act, marker);
 289
 290                 Predicate * unset_predicate = NULL;
 291                 bool branch_found = follow_branch(&curr_pred, next_inst, next_act, &unset_predicate);
 292
 293                 // A branch with unset predicate expression is detected
 294                 if (!branch_found && unset_predicate != NULL) {
 295                         bool amended = amend_predicate_expr(curr_pred, next_inst, next_act);
 296                         if (amended)
 297                                 continue;
 298                         else {
 299                                 curr_pred = unset_predicate;
 300                                 branch_found = true;
 301                         }
 302                 }
 303
 304                 // Detect loops
 305                 if (!branch_found && inst_id_map.contains(next_inst)) {
 306                         FuncInst * curr_inst = curr_pred->get_func_inst();
 307                         uint32_t curr_id = inst_id_map.get(curr_inst);
 308                         uint32_t next_id = inst_id_map.get(next_inst);
 309
 310                         if (curr_id >= next_id) {
 311                                 Predicate * old_pred = inst_pred_map.get(next_inst);
 312                                 Predicate * back_pred = old_pred->get_parent();
 313
 314                                 // For updating weights
 315                                 leaves_tmp_storage.push_back(curr_pred);
 316
 317                                 // Add to the set of backedges
 318                                 curr_pred->add_backedge(back_pred);
 319                                 curr_pred = back_pred;
 320                                 continue;
 321                         }
 322                 }
 323
 324                 // Generate new branches
 325                 if (!branch_found) {
 326                         SnapVector<struct half_pred_expr *> half_pred_expressions;
 327                         infer_predicates(next_inst, next_act, &half_pred_expressions);
 328                         generate_predicates(curr_pred, next_inst, &half_pred_expressions);
 329                         continue;
 330                 }
 331
 332                 if (next_act->is_write())
 333                         curr_pred->set_write(true);
 334
 335                 if (next_act->is_read()) {
 336                         /* Only need to store the locations of read actions */
 337                         loc_act_map.put(next_act->get_location(), next_act);
 338                 }
 339
 340                 inst_pred_map.put(next_inst, curr_pred);
 341                 if (!inst_id_map.contains(next_inst))
 342                         inst_id_map.put(next_inst, inst_counter++);
 343
 344                 it = it->getNext();
 345                 curr_pred->incr_expl_count();
 346         }
 347
 348         if (curr_pred->get_exit() == NULL) {
 349                 // Exit predicate is unset yet
 350                 curr_pred->set_exit(predicate_tree_exit);
 351         }
 352
 353         leaves_tmp_storage.push_back(curr_pred);
 354         update_predicate_tree_weight();
 355 }
 356
 357 /* Given curr_pred and next_inst, find the branch following curr_pred that
 358  * contains next_inst and the correct predicate.
 359  * @return true if branch found, false otherwise.
 360  */
 361 bool FuncNode::follow_branch(Predicate ** curr_pred, FuncInst * next_inst,
 362                                                                                                                  ModelAction * next_act, Predicate ** unset_predicate)
 363 {
 364         /* Check if a branch with func_inst and corresponding predicate exists */
 365         bool branch_found = false;
 366         ModelVector<Predicate *> * branches = (*curr_pred)->get_children();
 367         for (uint i = 0;i < branches->size();i++) {
 368                 Predicate * branch = (*branches)[i];
 369                 if (branch->get_func_inst() != next_inst)
 370                         continue;
 371
 372                 /* Check against predicate expressions */
 373                 bool predicate_correct = true;
 374                 PredExprSet * pred_expressions = branch->get_pred_expressions();
 375
 376                 /* Only read and rmw actions my have unset predicate expressions */
 377                 if (pred_expressions->getSize() == 0) {
 378                         predicate_correct = false;
 379                         if (*unset_predicate == NULL)
 380                                 *unset_predicate = branch;
 381                         else
 382                                 ASSERT(false);
 383
 384                         continue;
 385                 }
 386
 387                 PredExprSetIter * pred_expr_it = pred_expressions->iterator();
 388                 while (pred_expr_it->hasNext()) {
 389                         pred_expr * pred_expression = pred_expr_it->next();
 390                         uint64_t last_read, next_read;
 391                         bool equality;
 392
 393                         switch(pred_expression->token) {
 394                         case NOPREDICATE:
 395                                 predicate_correct = true;
 396                                 break;
 397                         case EQUALITY:
 398                                 FuncInst * to_be_compared;
 399                                 ModelAction * last_act;
 400
 401                                 to_be_compared = pred_expression->func_inst;
 402                                 last_act = to_be_compared->get_associated_act(marker);
 403
 404                                 last_read = last_act->get_reads_from_value();
 405                                 next_read = next_act->get_reads_from_value();
 406                                 equality = (last_read == next_read);
 407                                 if (equality != pred_expression->value)
 408                                         predicate_correct = false;
 409
 410                                 break;
 411                         case NULLITY:
 412                                 next_read = next_act->get_reads_from_value();
 413                                 // TODO: implement likely to be null
 414                                 equality = ( (void*) (next_read & 0xffffffff) == NULL);
 415                                 if (equality != pred_expression->value)
 416                                         predicate_correct = false;
 417                                 break;
 418                         default:
 419                                 predicate_correct = false;
 420                                 model_print("unkown predicate token\n");
 421                                 break;
 422                         }
 423                 }
 424
 425                 delete pred_expr_it;
 426
 427                 if (predicate_correct) {
 428                         *curr_pred = branch;
 429                         branch_found = true;
 430                         break;
 431                 }
 432         }
 433
 434         return branch_found;
 435 }
 436
 437 /* Infer predicate expressions, which are generated in FuncNode::generate_predicates */
 438 void FuncNode::infer_predicates(FuncInst * next_inst, ModelAction * next_act,
 439                                                                                                                                 SnapVector<struct half_pred_expr *> * half_pred_expressions)
 440 {
 441         void * loc = next_act->get_location();
 442
 443         if (next_inst->is_read()) {
 444                 /* read + rmw */
 445                 if ( loc_act_map.contains(loc) ) {
 446                         ModelAction * last_act = loc_act_map.get(loc);
 447                         FuncInst * last_inst = get_inst(last_act);
 448                         struct half_pred_expr * expression = new half_pred_expr(EQUALITY, last_inst);
 449                         half_pred_expressions->push_back(expression);
 450                 } else if ( next_inst->is_single_location() ) {
 451                         loc_set_t * loc_may_equal = loc_may_equal_map->get(loc);
 452
 453                         if (loc_may_equal != NULL) {
 454                                 loc_set_iter * loc_it = loc_may_equal->iterator();
 455                                 while (loc_it->hasNext()) {
 456                                         void * neighbor = loc_it->next();
 457                                         if (loc_act_map.contains(neighbor)) {
 458                                                 ModelAction * last_act = loc_act_map.get(neighbor);
 459                                                 FuncInst * last_inst = get_inst(last_act);
 460
 461                                                 struct half_pred_expr * expression = new half_pred_expr(EQUALITY, last_inst);
 462                                                 half_pred_expressions->push_back(expression);
 463                                         }
 464                                 }
 465
 466                                 delete loc_it;
 467                         }
 468                 } else {
 469                         // next_inst is not single location
 470                         uint64_t read_val = next_act->get_reads_from_value();
 471
 472                         // only infer NULLITY predicate when it is actually NULL.
 473                         if ( (void*)read_val == NULL) {
 474                                 struct half_pred_expr * expression = new half_pred_expr(NULLITY, NULL);
 475                                 half_pred_expressions->push_back(expression);
 476                         }
 477                 }
 478         } else {
 479                 /* Pure writes */
 480                 // TODO: do anything here?
 481         }
 482 }
 483
 484 /* Able to generate complex predicates when there are multiple predciate expressions */
 485 void FuncNode::generate_predicates(Predicate * curr_pred, FuncInst * next_inst,
 486                                                                                                                                          SnapVector<struct half_pred_expr *> * half_pred_expressions)
 487 {
 488         if (half_pred_expressions->size() == 0) {
 489                 Predicate * new_pred = new Predicate(next_inst);
 490                 curr_pred->add_child(new_pred);
 491                 new_pred->set_parent(curr_pred);
 492
 493                 /* Maintain predicate leaves */
 494                 predicate_leaves.add(new_pred);
 495                 predicate_leaves.remove(curr_pred);
 496
 497                 /* entry predicates and predicates containing pure write actions
 498                  * have no predicate expressions */
 499                 if ( curr_pred->is_entry_predicate() )
 500                         new_pred->add_predicate_expr(NOPREDICATE, NULL, true);
 501                 else if (next_inst->is_write()) {
 502                         /* next_inst->is_write() <==> pure writes */
 503                         new_pred->add_predicate_expr(NOPREDICATE, NULL, true);
 504                 }
 505
 506                 return;
 507         }
 508
 509         SnapVector<Predicate *> predicates;
 510
 511         struct half_pred_expr * half_expr = (*half_pred_expressions)[0];
 512         predicates.push_back(new Predicate(next_inst));
 513         predicates.push_back(new Predicate(next_inst));
 514
 515         predicates[0]->add_predicate_expr(half_expr->token, half_expr->func_inst, true);
 516         predicates[1]->add_predicate_expr(half_expr->token, half_expr->func_inst, false);
 517
 518         for (uint i = 1;i < half_pred_expressions->size();i++) {
 519                 half_expr = (*half_pred_expressions)[i];
 520
 521                 uint old_size = predicates.size();
 522                 for (uint j = 0;j < old_size;j++) {
 523                         Predicate * pred = predicates[j];
 524                         Predicate * new_pred = new Predicate(next_inst);
 525                         new_pred->copy_predicate_expr(pred);
 526
 527                         pred->add_predicate_expr(half_expr->token, half_expr->func_inst, true);
 528                         new_pred->add_predicate_expr(half_expr->token, half_expr->func_inst, false);
 529
 530                         predicates.push_back(new_pred);
 531                 }
 532         }
 533
 534         for (uint i = 0;i < predicates.size();i++) {
 535                 Predicate * pred= predicates[i];
 536                 curr_pred->add_child(pred);
 537                 pred->set_parent(curr_pred);
 538
 539                 /* Add new predicate leaves */
 540                 predicate_leaves.add(pred);
 541         }
 542
 543         /* Remove predicate node that has children */
 544         predicate_leaves.remove(curr_pred);
 545
 546         /* Free memories allocated by infer_predicate */
 547         for (uint i = 0;i < half_pred_expressions->size();i++) {
 548                 struct half_pred_expr * tmp = (*half_pred_expressions)[i];
 549                 snapshot_free(tmp);
 550         }
 551 }
 552
 553 /* Amend predicates that contain no predicate expressions. Currenlty only amend with NULLITY predicates */
 554 bool FuncNode::amend_predicate_expr(Predicate * curr_pred, FuncInst * next_inst, ModelAction * next_act)
 555 {
 556         ModelVector<Predicate *> * children = curr_pred->get_children();
 557
 558         Predicate * unset_pred = NULL;
 559         for (uint i = 0;i < children->size();i++) {
 560                 Predicate * child = (*children)[i];
 561                 if (child->get_func_inst() == next_inst) {
 562                         unset_pred = child;
 563                         break;
 564                 }
 565         }
 566
 567         uint64_t read_val = next_act->get_reads_from_value();
 568
 569         // only generate NULLITY predicate when it is actually NULL.
 570         if ( !next_inst->is_single_location() && (void*)read_val == NULL ) {
 571                 Predicate * new_pred = new Predicate(next_inst);
 572
 573                 curr_pred->add_child(new_pred);
 574                 new_pred->set_parent(curr_pred);
 575
 576                 unset_pred->add_predicate_expr(NULLITY, NULL, false);
 577                 new_pred->add_predicate_expr(NULLITY, NULL, true);
 578
 579                 return true;
 580         }
 581
 582         return false;
 583 }
 584
 585 void FuncNode::add_to_val_loc_map(uint64_t val, void * loc)
 586 {
 587         loc_set_t * locations = val_loc_map->get(val);
 588
 589         if (locations == NULL) {
 590                 locations = new loc_set_t();
 591                 val_loc_map->put(val, locations);
 592         }
 593
 594         update_loc_may_equal_map(loc, locations);
 595         locations->add(loc);
 596         // values_may_read_from->add(val);
 597 }
 598
 599 void FuncNode::add_to_val_loc_map(value_set_t * values, void * loc)
 600 {
 601         if (values == NULL)
 602                 return;
 603
 604         value_set_iter * it = values->iterator();
 605         while (it->hasNext()) {
 606                 uint64_t val = it->next();
 607                 add_to_val_loc_map(val, loc);
 608         }
 609
 610         delete it;
 611 }
 612
 613 void FuncNode::update_loc_may_equal_map(void * new_loc, loc_set_t * old_locations)
 614 {
 615         if ( old_locations->contains(new_loc) )
 616                 return;
 617
 618         loc_set_t * neighbors = loc_may_equal_map->get(new_loc);
 619
 620         if (neighbors == NULL) {
 621                 neighbors = new loc_set_t();
 622                 loc_may_equal_map->put(new_loc, neighbors);
 623         }
 624
 625         loc_set_iter * loc_it = old_locations->iterator();
 626         while (loc_it->hasNext()) {
 627                 // new_loc: { old_locations, ... }
 628                 void * member = loc_it->next();
 629                 neighbors->add(member);
 630
 631                 // for each i in old_locations, i : { new_loc, ... }
 632                 loc_set_t * _neighbors = loc_may_equal_map->get(member);
 633                 if (_neighbors == NULL) {
 634                         _neighbors = new loc_set_t();
 635                         loc_may_equal_map->put(member, _neighbors);
 636                 }
 637                 _neighbors->add(new_loc);
 638         }
 639
 640         delete loc_it;
 641 }
 642
 643 /* Every time a thread enters a function, set its position to the predicate tree entry */
 644 void FuncNode::init_predicate_tree_position(thread_id_t tid)
 645 {
 646         int thread_id = id_to_int(tid);
 647         if (predicate_tree_position.size() <= (uint) thread_id)
 648                 predicate_tree_position.resize(thread_id + 1);
 649
 650         predicate_tree_position[thread_id] = predicate_tree_entry;
 651 }
 652
 653 void FuncNode::set_predicate_tree_position(thread_id_t tid, Predicate * pred)
 654 {
 655         int thread_id = id_to_int(tid);
 656         predicate_tree_position[thread_id] = pred;
 657 }
 658
 659 /* @return The position of a thread in a predicate tree */
 660 Predicate * FuncNode::get_predicate_tree_position(thread_id_t tid)
 661 {
 662         int thread_id = id_to_int(tid);
 663         return predicate_tree_position[thread_id];
 664 }
 665
 666 /* Make sure elements of thrd_inst_act_map are initialized properly when threads enter functions */
 667 void FuncNode::init_inst_act_map(thread_id_t tid)
 668 {
 669         int thread_id = id_to_int(tid);
 670         SnapVector<inst_act_map_t *> * thrd_inst_act_map = history->getThrdInstActMap(func_id);
 671         uint old_size = thrd_inst_act_map->size();
 672
 673         if (thrd_inst_act_map->size() <= (uint) thread_id) {
 674                 uint new_size = thread_id + 1;
 675                 thrd_inst_act_map->resize(new_size);
 676
 677                 for (uint i = old_size;i < new_size;i++)
 678                         (*thrd_inst_act_map)[i] = new inst_act_map_t(128);
 679         }
 680 }
 681
 682 /* Reset elements of thrd_inst_act_map when threads exit functions */
 683 void FuncNode::reset_inst_act_map(thread_id_t tid)
 684 {
 685         int thread_id = id_to_int(tid);
 686         SnapVector<inst_act_map_t *> * thrd_inst_act_map = history->getThrdInstActMap(func_id);
 687
 688         inst_act_map_t * map = (*thrd_inst_act_map)[thread_id];
 689         map->reset();
 690 }
 691
 692 void FuncNode::update_inst_act_map(thread_id_t tid, ModelAction * read_act)
 693 {
 694         int thread_id = id_to_int(tid);
 695         SnapVector<inst_act_map_t *> * thrd_inst_act_map = history->getThrdInstActMap(func_id);
 696
 697         inst_act_map_t * map = (*thrd_inst_act_map)[thread_id];
 698         FuncInst * read_inst = get_inst(read_act);
 699         map->put(read_inst, read_act);
 700 }
 701
 702 inst_act_map_t * FuncNode::get_inst_act_map(thread_id_t tid)
 703 {
 704         int thread_id = id_to_int(tid);
 705         SnapVector<inst_act_map_t *> * thrd_inst_act_map = history->getThrdInstActMap(func_id);
 706
 707         return (*thrd_inst_act_map)[thread_id];
 708 }
 709
 710 /* Add FuncNodes that this node may follow */
 711 void FuncNode::add_out_edge(FuncNode * other)
 712 {
 713         if ( !edge_table.contains(other) ) {
 714                 edge_table.put(other, OUT_EDGE);
 715                 out_edges.push_back(other);
 716                 return;
 717         }
 718
 719         edge_type_t edge = edge_table.get(other);
 720         if (edge == IN_EDGE) {
 721                 edge_table.put(other, BI_EDGE);
 722                 out_edges.push_back(other);
 723         }
 724 }
 725
 726 /* Compute the distance between this FuncNode and the target node.
 727  * Return -1 if the target node is unreachable or the actual distance
 728  * is greater than max_step.
 729  */
 730 int FuncNode::compute_distance(FuncNode * target, int max_step)
 731 {
 732         if (target == NULL)
 733                 return -1;
 734         else if (target == this)
 735                 return 0;
 736
 737         SnapList<FuncNode *> queue;
 738         HashTable<FuncNode *, int, uintptr_t, 0> distances(128);
 739
 740         queue.push_back(this);
 741         distances.put(this, 0);
 742
 743         while (!queue.empty()) {
 744                 FuncNode * curr = queue.front();
 745                 queue.pop_front();
 746                 int dist = distances.get(curr);
 747
 748                 if (max_step <= dist)
 749                         return -1;
 750
 751                 ModelList<FuncNode *> * outEdges = curr->get_out_edges();
 752                 mllnode<FuncNode *> * it;
 753                 for (it = outEdges->begin();it != NULL;it = it->getNext()) {
 754                         FuncNode * out_node = it->getVal();
 755
 756                         /* This node has not been visited before */
 757                         if ( !distances.contains(out_node) ) {
 758                                 if (out_node == target)
 759                                         return dist + 1;
 760
 761                                 queue.push_back(out_node);
 762                                 distances.put(out_node, dist + 1);
 763                         }
 764                 }
 765         }
 766
 767         /* Target node is unreachable */
 768         return -1;
 769 }
 770
 771 void FuncNode::add_failed_predicate(Predicate * pred)
 772 {
 773         failed_predicates.add(pred);
 774 }
 775
 776 /* Implement quick sort to sort leaves before assigning base scores */
 777 template<typename _Tp>
 778 static int partition(ModelVector<_Tp *> * arr, int low, int high)
 779 {
 780         unsigned int pivot = (*arr)[high] -> get_depth();
 781         int i = low - 1;
 782
 783         for (int j = low;j <= high - 1;j ++) {
 784                 if ( (*arr)[j] -> get_depth() < pivot ) {
 785                         i ++;
 786                         _Tp * tmp = (*arr)[i];
 787                         (*arr)[i] = (*arr)[j];
 788                         (*arr)[j] = tmp;
 789                 }
 790         }
 791
 792         _Tp * tmp = (*arr)[i + 1];
 793         (*arr)[i + 1] = (*arr)[high];
 794         (*arr)[high] = tmp;
 795
 796         return i + 1;
 797 }
 798
 799 /* Implement quick sort to sort leaves before assigning base scores */
 800 template<typename _Tp>
 801 static void quickSort(ModelVector<_Tp *> * arr, int low, int high)
 802 {
 803         if (low < high) {
 804                 int pi = partition(arr, low, high);
 805
 806                 quickSort(arr, low, pi - 1);
 807                 quickSort(arr, pi + 1, high);
 808         }
 809 }
 810
 811 void FuncNode::assign_initial_weight()
 812 {
 813         PredSetIter * it = predicate_leaves.iterator();
 814         leaves_tmp_storage.clear();
 815
 816         while (it->hasNext()) {
 817                 Predicate * pred = it->next();
 818                 double weight = 100.0 / sqrt(pred->get_expl_count() + pred->get_fail_count() + 1);
 819                 pred->set_weight(weight);
 820                 leaves_tmp_storage.push_back(pred);
 821         }
 822         delete it;
 823
 824         quickSort(&leaves_tmp_storage, 0, leaves_tmp_storage.size() - 1);
 825
 826         // assign scores for internal nodes;
 827         while ( !leaves_tmp_storage.empty() ) {
 828                 Predicate * leaf = leaves_tmp_storage.back();
 829                 leaves_tmp_storage.pop_back();
 830
 831                 Predicate * curr = leaf->get_parent();
 832                 while (curr != NULL) {
 833                         if (curr->get_weight() != 0) {
 834                                 // Has been exlpored
 835                                 break;
 836                         }
 837
 838                         ModelVector<Predicate *> * children = curr->get_children();
 839                         double weight_sum = 0;
 840                         bool has_unassigned_node = false;
 841
 842                         for (uint i = 0;i < children->size();i++) {
 843                                 Predicate * child = (*children)[i];
 844
 845                                 // If a child has unassigned weight
 846                                 double weight = child->get_weight();
 847                                 if (weight == 0) {
 848                                         has_unassigned_node = true;
 849                                         break;
 850                                 } else
 851                                         weight_sum += weight;
 852                         }
 853
 854                         if (!has_unassigned_node) {
 855                                 double average_weight = (double) weight_sum / (double) children->size();
 856                                 double weight = average_weight * pow(0.9, curr->get_depth());
 857                                 curr->set_weight(weight);
 858                         } else
 859                                 break;
 860
 861                         curr = curr->get_parent();
 862                 }
 863         }
 864 }
 865
 866 void FuncNode::update_predicate_tree_weight()
 867 {
 868         if (marker == 2) {
 869                 // Predicate tree is initially built
 870                 assign_initial_weight();
 871                 return;
 872         }
 873
 874         weight_debug_vec.clear();
 875
 876         PredSetIter * it = failed_predicates.iterator();
 877         while (it->hasNext()) {
 878                 Predicate * pred = it->next();
 879                 leaves_tmp_storage.push_back(pred);
 880         }
 881         delete it;
 882         failed_predicates.reset();
 883
 884         quickSort(&leaves_tmp_storage, 0, leaves_tmp_storage.size() - 1);
 885         for (uint i = 0;i < leaves_tmp_storage.size();i++) {
 886                 Predicate * pred = leaves_tmp_storage[i];
 887                 double weight = 100.0 / sqrt(pred->get_expl_count() + pred->get_fail_count() + 1);
 888                 pred->set_weight(weight);
 889         }
 890
 891         // Update weights in internal nodes
 892         while ( !leaves_tmp_storage.empty() ) {
 893                 Predicate * leaf = leaves_tmp_storage.back();
 894                 leaves_tmp_storage.pop_back();
 895
 896                 Predicate * curr = leaf->get_parent();
 897                 while (curr != NULL) {
 898                         ModelVector<Predicate *> * children = curr->get_children();
 899                         double weight_sum = 0;
 900                         bool has_unassigned_node = false;
 901
 902                         for (uint i = 0;i < children->size();i++) {
 903                                 Predicate * child = (*children)[i];
 904
 905                                 double weight = child->get_weight();
 906                                 if (weight != 0)
 907                                         weight_sum += weight;
 908                                 else if ( predicate_leaves.contains(child) ) {
 909                                         // If this child is a leaf
 910                                         double weight = 100.0 / sqrt(child->get_expl_count() + 1);
 911                                         child->set_weight(weight);
 912                                         weight_sum += weight;
 913                                 } else {
 914                                         has_unassigned_node = true;
 915                                         weight_debug_vec.push_back(child);      // For debugging purpose
 916                                         break;
 917                                 }
 918                         }
 919
 920                         if (!has_unassigned_node) {
 921                                 double average_weight = (double) weight_sum / (double) children->size();
 922                                 double weight = average_weight * pow(0.9, curr->get_depth());
 923                                 curr->set_weight(weight);
 924                         } else
 925                                 break;
 926
 927                         curr = curr->get_parent();
 928                 }
 929         }
 930
 931         for (uint i = 0;i < weight_debug_vec.size();i++) {
 932                 Predicate * tmp = weight_debug_vec[i];
 933                 ASSERT( tmp->get_weight() != 0 );
 934         }
 935 }
 936
 937 void FuncNode::print_predicate_tree()
 938 {
 939         model_print("digraph function_%s {\n", func_name);
 940         predicate_tree_entry->print_pred_subtree();
 941         predicate_tree_exit->print_predicate();
 942         model_print("}\n");     // end of graph
 943 }