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         HashSet<ModelAction *, uintptr_t, 2> write_actions;
 181
 182         /* build inst_list from act_list for later processing */
 183         func_inst_list_t inst_list;
 184         action_list_t rw_act_list;
 185
 186         for (sllnode<ModelAction *> * it = act_list->begin();it != NULL;it = it->getNext()) {
 187                 ModelAction * act = it->getVal();
 188
 189                 // Use the original action type and decrement ref count
 190                 // so that actions may be deleted by Execution::collectActions
 191                 if (act->get_original_type() != ATOMIC_NOP && act->get_swap_flag() == false)
 192                         act->use_original_type();
 193
 194                 act->decr_func_ref_count();
 195
 196                 if (act->is_read()) {
 197                         // For every read or rmw actions in this list, the reads_from was marked, and not deleted.
 198                         // So it is safe to call get_reads_from
 199                         ModelAction * rf = act->get_reads_from();
 200                         if (rf->get_original_type() != ATOMIC_NOP && rf->get_swap_flag() == false)
 201                                 rf->use_original_type();
 202
 203                         rf->decr_func_ref_count();
 204                 }
 205
 206                 FuncInst * func_inst = get_inst(act);
 207                 void * loc = act->get_location();
 208
 209                 if (func_inst == NULL)
 210                         continue;
 211
 212                 inst_list.push_back(func_inst);
 213                 bool act_added = false;
 214
 215                 if (act->is_write()) {
 216                         rw_act_list.push_back(act);
 217                         act_added = true;
 218                         if (!write_locations->contains(loc)) {
 219                                 write_locations->add(loc);
 220                                 history->update_loc_wr_func_nodes_map(loc, this);
 221                         }
 222                 }
 223
 224                 if (act->is_read()) {
 225                         if (!act_added)
 226                                 rw_act_list.push_back(act);
 227
 228                         /* If func_inst may only read_from a single location, then:
 229                          *
 230                          * The first time an action reads from some location,
 231                          * import all the values that have been written to this
 232                          * location from ModelHistory and notify ModelHistory
 233                          * that this FuncNode may read from this location.
 234                          */
 235                         if (!read_locations->contains(loc) && func_inst->is_single_location()) {
 236                                 read_locations->add(loc);
 237                                 value_set_t * write_values = write_history->get(loc);
 238                                 add_to_val_loc_map(write_values, loc);
 239                                 history->update_loc_rd_func_nodes_map(loc, this);
 240                         }
 241                 }
 242         }
 243
 244         update_inst_tree(&inst_list);
 245         update_predicate_tree(&rw_act_list);
 246
 247         // Revert back action types and free
 248         for (sllnode<ModelAction *> * it = act_list->begin(); it != NULL;) {
 249                 ModelAction * act = it->getVal();
 250                 // Do iteration early in case we delete read actions
 251                 it = it->getNext();
 252
 253                 // Collect write actions and reads_froms
 254                 if (act->is_read()) {
 255                         if (act->is_rmw()) {
 256                                 write_actions.add(act);
 257                         }
 258
 259                         ModelAction * rf = act->get_reads_from();
 260                         write_actions.add(rf);
 261                 } else if (act->is_write()) {
 262                         write_actions.add(act);
 263                 }
 264
 265                 // Revert back action types
 266                 if (act->is_read()) {
 267                         ModelAction * rf = act->get_reads_from();
 268                         if (rf->get_swap_flag() == true)
 269                                 rf->use_original_type();
 270                 }
 271
 272                 if (act->get_swap_flag() == true)
 273                         act->use_original_type();
 274
 275                 //  Free read actions
 276                 if (act->is_read()) {
 277                         if (act->is_rmw()) {
 278                                 // Do nothing. Its reads_from can not be READY_FREE
 279                         } else {
 280                                 ModelAction *rf = act->get_reads_from();
 281                                 if (rf->is_free()) {
 282                                         model_print("delete read %d; %p\n", act->get_seq_number(), act);
 283                                         delete act;
 284                                 }
 285                         }
 286                 }
 287         }
 288
 289         // Free write actions if possible
 290         HSIterator<ModelAction *, uintptr_t, 2> * it = write_actions.iterator();
 291         while (it->hasNext()) {
 292                 ModelAction * act = it->next();
 293
 294                 if (act->is_free() && act->get_func_ref_count() == 0)
 295                         delete act;
 296         }
 297         delete it;
 298
 299 //      print_predicate_tree();
 300 }
 301
 302 /**
 303  * @brief Link FuncInsts in inst_list  - add one FuncInst to another's predecessors and successors
 304  * @param inst_list A list of FuncInsts
 305  */
 306 void FuncNode::update_inst_tree(func_inst_list_t * inst_list)
 307 {
 308         if (inst_list == NULL)
 309                 return;
 310         else if (inst_list->size() == 0)
 311                 return;
 312
 313         /* start linking */
 314         sllnode<FuncInst *>* it = inst_list->begin();
 315         sllnode<FuncInst *>* prev;
 316
 317         /* add the first instruction to the list of entry insts */
 318         FuncInst * entry_inst = it->getVal();
 319         add_entry_inst(entry_inst);
 320
 321         it = it->getNext();
 322         while (it != NULL) {
 323                 prev = it->getPrev();
 324
 325                 FuncInst * prev_inst = prev->getVal();
 326                 FuncInst * curr_inst = it->getVal();
 327
 328                 prev_inst->add_succ(curr_inst);
 329                 curr_inst->add_pred(prev_inst);
 330
 331                 it = it->getNext();
 332         }
 333 }
 334
 335 void FuncNode::update_predicate_tree(action_list_t * act_list)
 336 {
 337         if (act_list == NULL || act_list->size() == 0)
 338                 return;
 339
 340         incr_marker();
 341         uint32_t inst_counter = 0;
 342
 343         // Clear hashtables
 344         loc_act_map.reset();
 345         inst_pred_map.reset();
 346         inst_id_map.reset();
 347
 348         // Clear the set of leaves encountered in this path
 349         leaves_tmp_storage.clear();
 350
 351         sllnode<ModelAction *> *it = act_list->begin();
 352         Predicate * curr_pred = predicate_tree_entry;
 353         while (it != NULL) {
 354                 ModelAction * next_act = it->getVal();
 355                 FuncInst * next_inst = get_inst(next_act);
 356                 next_inst->set_associated_act(next_act, marker);
 357
 358                 Predicate * unset_predicate = NULL;
 359                 bool branch_found = follow_branch(&curr_pred, next_inst, next_act, &unset_predicate);
 360
 361                 // A branch with unset predicate expression is detected
 362                 if (!branch_found && unset_predicate != NULL) {
 363                         bool amended = amend_predicate_expr(curr_pred, next_inst, next_act);
 364                         if (amended)
 365                                 continue;
 366                         else {
 367                                 curr_pred = unset_predicate;
 368                                 branch_found = true;
 369                         }
 370                 }
 371
 372                 // Detect loops
 373                 if (!branch_found && inst_id_map.contains(next_inst)) {
 374                         FuncInst * curr_inst = curr_pred->get_func_inst();
 375                         uint32_t curr_id = inst_id_map.get(curr_inst);
 376                         uint32_t next_id = inst_id_map.get(next_inst);
 377
 378                         if (curr_id >= next_id) {
 379                                 Predicate * old_pred = inst_pred_map.get(next_inst);
 380                                 Predicate * back_pred = old_pred->get_parent();
 381
 382                                 // For updating weights
 383                                 leaves_tmp_storage.push_back(curr_pred);
 384
 385                                 // Add to the set of backedges
 386                                 curr_pred->add_backedge(back_pred);
 387                                 curr_pred = back_pred;
 388                                 continue;
 389                         }
 390                 }
 391
 392                 // Generate new branches
 393                 if (!branch_found) {
 394                         SnapVector<struct half_pred_expr *> half_pred_expressions;
 395                         infer_predicates(next_inst, next_act, &half_pred_expressions);
 396                         generate_predicates(curr_pred, next_inst, &half_pred_expressions);
 397                         continue;
 398                 }
 399
 400                 if (next_act->is_write())
 401                         curr_pred->set_write(true);
 402
 403                 if (next_act->is_read()) {
 404                         /* Only need to store the locations of read actions */
 405                         loc_act_map.put(next_act->get_location(), next_act);
 406                 }
 407
 408                 inst_pred_map.put(next_inst, curr_pred);
 409                 if (!inst_id_map.contains(next_inst))
 410                         inst_id_map.put(next_inst, inst_counter++);
 411
 412                 it = it->getNext();
 413                 curr_pred->incr_expl_count();
 414         }
 415
 416         if (curr_pred->get_exit() == NULL) {
 417                 // Exit predicate is unset yet
 418                 curr_pred->set_exit(predicate_tree_exit);
 419         }
 420
 421         leaves_tmp_storage.push_back(curr_pred);
 422         update_predicate_tree_weight();
 423 }
 424
 425 /* Given curr_pred and next_inst, find the branch following curr_pred that
 426  * contains next_inst and the correct predicate.
 427  * @return true if branch found, false otherwise.
 428  */
 429 bool FuncNode::follow_branch(Predicate ** curr_pred, FuncInst * next_inst,
 430                                                                                                                  ModelAction * next_act, Predicate ** unset_predicate)
 431 {
 432         /* Check if a branch with func_inst and corresponding predicate exists */
 433         bool branch_found = false;
 434         ModelVector<Predicate *> * branches = (*curr_pred)->get_children();
 435         for (uint i = 0;i < branches->size();i++) {
 436                 Predicate * branch = (*branches)[i];
 437                 if (branch->get_func_inst() != next_inst)
 438                         continue;
 439
 440                 /* Check against predicate expressions */
 441                 bool predicate_correct = true;
 442                 PredExprSet * pred_expressions = branch->get_pred_expressions();
 443
 444                 /* Only read and rmw actions my have unset predicate expressions */
 445                 if (pred_expressions->getSize() == 0) {
 446                         predicate_correct = false;
 447                         if (*unset_predicate == NULL)
 448                                 *unset_predicate = branch;
 449                         else
 450                                 ASSERT(false);
 451
 452                         continue;
 453                 }
 454
 455                 PredExprSetIter * pred_expr_it = pred_expressions->iterator();
 456                 while (pred_expr_it->hasNext()) {
 457                         pred_expr * pred_expression = pred_expr_it->next();
 458                         uint64_t last_read, next_read;
 459                         bool equality;
 460
 461                         switch(pred_expression->token) {
 462                         case NOPREDICATE:
 463                                 predicate_correct = true;
 464                                 break;
 465                         case EQUALITY:
 466                                 FuncInst * to_be_compared;
 467                                 ModelAction * last_act;
 468
 469                                 to_be_compared = pred_expression->func_inst;
 470                                 last_act = to_be_compared->get_associated_act(marker);
 471
 472                                 last_read = last_act->get_reads_from_value();
 473                                 next_read = next_act->get_reads_from_value();
 474                                 equality = (last_read == next_read);
 475                                 if (equality != pred_expression->value)
 476                                         predicate_correct = false;
 477
 478                                 break;
 479                         case NULLITY:
 480                                 next_read = next_act->get_reads_from_value();
 481                                 // TODO: implement likely to be null
 482                                 equality = ( (void*) (next_read & 0xffffffff) == NULL);
 483                                 if (equality != pred_expression->value)
 484                                         predicate_correct = false;
 485                                 break;
 486                         default:
 487                                 predicate_correct = false;
 488                                 model_print("unkown predicate token\n");
 489                                 break;
 490                         }
 491                 }
 492
 493                 delete pred_expr_it;
 494
 495                 if (predicate_correct) {
 496                         *curr_pred = branch;
 497                         branch_found = true;
 498                         break;
 499                 }
 500         }
 501
 502         return branch_found;
 503 }
 504
 505 /* Infer predicate expressions, which are generated in FuncNode::generate_predicates */
 506 void FuncNode::infer_predicates(FuncInst * next_inst, ModelAction * next_act,
 507                                                                                                                                 SnapVector<struct half_pred_expr *> * half_pred_expressions)
 508 {
 509         void * loc = next_act->get_location();
 510
 511         if (next_inst->is_read()) {
 512                 /* read + rmw */
 513                 if ( loc_act_map.contains(loc) ) {
 514                         ModelAction * last_act = loc_act_map.get(loc);
 515                         FuncInst * last_inst = get_inst(last_act);
 516                         struct half_pred_expr * expression = new half_pred_expr(EQUALITY, last_inst);
 517                         half_pred_expressions->push_back(expression);
 518                 } else if ( next_inst->is_single_location() ) {
 519                         loc_set_t * loc_may_equal = loc_may_equal_map->get(loc);
 520
 521                         if (loc_may_equal != NULL) {
 522                                 loc_set_iter * loc_it = loc_may_equal->iterator();
 523                                 while (loc_it->hasNext()) {
 524                                         void * neighbor = loc_it->next();
 525                                         if (loc_act_map.contains(neighbor)) {
 526                                                 ModelAction * last_act = loc_act_map.get(neighbor);
 527                                                 FuncInst * last_inst = get_inst(last_act);
 528
 529                                                 struct half_pred_expr * expression = new half_pred_expr(EQUALITY, last_inst);
 530                                                 half_pred_expressions->push_back(expression);
 531                                         }
 532                                 }
 533
 534                                 delete loc_it;
 535                         }
 536                 } else {
 537                         // next_inst is not single location
 538                         uint64_t read_val = next_act->get_reads_from_value();
 539
 540                         // only infer NULLITY predicate when it is actually NULL.
 541                         if ( (void*)read_val == NULL) {
 542                                 struct half_pred_expr * expression = new half_pred_expr(NULLITY, NULL);
 543                                 half_pred_expressions->push_back(expression);
 544                         }
 545                 }
 546         } else {
 547                 /* Pure writes */
 548                 // TODO: do anything here?
 549         }
 550 }
 551
 552 /* Able to generate complex predicates when there are multiple predciate expressions */
 553 void FuncNode::generate_predicates(Predicate * curr_pred, FuncInst * next_inst,
 554                                                                                                                                          SnapVector<struct half_pred_expr *> * half_pred_expressions)
 555 {
 556         if (half_pred_expressions->size() == 0) {
 557                 Predicate * new_pred = new Predicate(next_inst);
 558                 curr_pred->add_child(new_pred);
 559                 new_pred->set_parent(curr_pred);
 560
 561                 /* Maintain predicate leaves */
 562                 predicate_leaves.add(new_pred);
 563                 predicate_leaves.remove(curr_pred);
 564
 565                 /* entry predicates and predicates containing pure write actions
 566                  * have no predicate expressions */
 567                 if ( curr_pred->is_entry_predicate() )
 568                         new_pred->add_predicate_expr(NOPREDICATE, NULL, true);
 569                 else if (next_inst->is_write()) {
 570                         /* next_inst->is_write() <==> pure writes */
 571                         new_pred->add_predicate_expr(NOPREDICATE, NULL, true);
 572                 }
 573
 574                 return;
 575         }
 576
 577         SnapVector<Predicate *> predicates;
 578
 579         struct half_pred_expr * half_expr = (*half_pred_expressions)[0];
 580         predicates.push_back(new Predicate(next_inst));
 581         predicates.push_back(new Predicate(next_inst));
 582
 583         predicates[0]->add_predicate_expr(half_expr->token, half_expr->func_inst, true);
 584         predicates[1]->add_predicate_expr(half_expr->token, half_expr->func_inst, false);
 585
 586         for (uint i = 1;i < half_pred_expressions->size();i++) {
 587                 half_expr = (*half_pred_expressions)[i];
 588
 589                 uint old_size = predicates.size();
 590                 for (uint j = 0;j < old_size;j++) {
 591                         Predicate * pred = predicates[j];
 592                         Predicate * new_pred = new Predicate(next_inst);
 593                         new_pred->copy_predicate_expr(pred);
 594
 595                         pred->add_predicate_expr(half_expr->token, half_expr->func_inst, true);
 596                         new_pred->add_predicate_expr(half_expr->token, half_expr->func_inst, false);
 597
 598                         predicates.push_back(new_pred);
 599                 }
 600         }
 601
 602         for (uint i = 0;i < predicates.size();i++) {
 603                 Predicate * pred= predicates[i];
 604                 curr_pred->add_child(pred);
 605                 pred->set_parent(curr_pred);
 606
 607                 /* Add new predicate leaves */
 608                 predicate_leaves.add(pred);
 609         }
 610
 611         /* Remove predicate node that has children */
 612         predicate_leaves.remove(curr_pred);
 613
 614         /* Free memories allocated by infer_predicate */
 615         for (uint i = 0;i < half_pred_expressions->size();i++) {
 616                 struct half_pred_expr * tmp = (*half_pred_expressions)[i];
 617                 snapshot_free(tmp);
 618         }
 619 }
 620
 621 /* Amend predicates that contain no predicate expressions. Currenlty only amend with NULLITY predicates */
 622 bool FuncNode::amend_predicate_expr(Predicate * curr_pred, FuncInst * next_inst, ModelAction * next_act)
 623 {
 624         ModelVector<Predicate *> * children = curr_pred->get_children();
 625
 626         Predicate * unset_pred = NULL;
 627         for (uint i = 0;i < children->size();i++) {
 628                 Predicate * child = (*children)[i];
 629                 if (child->get_func_inst() == next_inst) {
 630                         unset_pred = child;
 631                         break;
 632                 }
 633         }
 634
 635         uint64_t read_val = next_act->get_reads_from_value();
 636
 637         // only generate NULLITY predicate when it is actually NULL.
 638         if ( !next_inst->is_single_location() && (void*)read_val == NULL ) {
 639                 Predicate * new_pred = new Predicate(next_inst);
 640
 641                 curr_pred->add_child(new_pred);
 642                 new_pred->set_parent(curr_pred);
 643
 644                 unset_pred->add_predicate_expr(NULLITY, NULL, false);
 645                 new_pred->add_predicate_expr(NULLITY, NULL, true);
 646
 647                 return true;
 648         }
 649
 650         return false;
 651 }
 652
 653 void FuncNode::add_to_val_loc_map(uint64_t val, void * loc)
 654 {
 655         loc_set_t * locations = val_loc_map->get(val);
 656
 657         if (locations == NULL) {
 658                 locations = new loc_set_t();
 659                 val_loc_map->put(val, locations);
 660         }
 661
 662         update_loc_may_equal_map(loc, locations);
 663         locations->add(loc);
 664         // values_may_read_from->add(val);
 665 }
 666
 667 void FuncNode::add_to_val_loc_map(value_set_t * values, void * loc)
 668 {
 669         if (values == NULL)
 670                 return;
 671
 672         value_set_iter * it = values->iterator();
 673         while (it->hasNext()) {
 674                 uint64_t val = it->next();
 675                 add_to_val_loc_map(val, loc);
 676         }
 677
 678         delete it;
 679 }
 680
 681 void FuncNode::update_loc_may_equal_map(void * new_loc, loc_set_t * old_locations)
 682 {
 683         if ( old_locations->contains(new_loc) )
 684                 return;
 685
 686         loc_set_t * neighbors = loc_may_equal_map->get(new_loc);
 687
 688         if (neighbors == NULL) {
 689                 neighbors = new loc_set_t();
 690                 loc_may_equal_map->put(new_loc, neighbors);
 691         }
 692
 693         loc_set_iter * loc_it = old_locations->iterator();
 694         while (loc_it->hasNext()) {
 695                 // new_loc: { old_locations, ... }
 696                 void * member = loc_it->next();
 697                 neighbors->add(member);
 698
 699                 // for each i in old_locations, i : { new_loc, ... }
 700                 loc_set_t * _neighbors = loc_may_equal_map->get(member);
 701                 if (_neighbors == NULL) {
 702                         _neighbors = new loc_set_t();
 703                         loc_may_equal_map->put(member, _neighbors);
 704                 }
 705                 _neighbors->add(new_loc);
 706         }
 707
 708         delete loc_it;
 709 }
 710
 711 /* Every time a thread enters a function, set its position to the predicate tree entry */
 712 void FuncNode::init_predicate_tree_position(thread_id_t tid)
 713 {
 714         int thread_id = id_to_int(tid);
 715         if (predicate_tree_position.size() <= (uint) thread_id)
 716                 predicate_tree_position.resize(thread_id + 1);
 717
 718         predicate_tree_position[thread_id] = predicate_tree_entry;
 719 }
 720
 721 void FuncNode::set_predicate_tree_position(thread_id_t tid, Predicate * pred)
 722 {
 723         int thread_id = id_to_int(tid);
 724         predicate_tree_position[thread_id] = pred;
 725 }
 726
 727 /* @return The position of a thread in a predicate tree */
 728 Predicate * FuncNode::get_predicate_tree_position(thread_id_t tid)
 729 {
 730         int thread_id = id_to_int(tid);
 731         return predicate_tree_position[thread_id];
 732 }
 733
 734 /* Make sure elements of thrd_inst_act_map are initialized properly when threads enter functions */
 735 void FuncNode::init_inst_act_map(thread_id_t tid)
 736 {
 737         int thread_id = id_to_int(tid);
 738         SnapVector<inst_act_map_t *> * thrd_inst_act_map = history->getThrdInstActMap(func_id);
 739         uint old_size = thrd_inst_act_map->size();
 740
 741         if (thrd_inst_act_map->size() <= (uint) thread_id) {
 742                 uint new_size = thread_id + 1;
 743                 thrd_inst_act_map->resize(new_size);
 744
 745                 for (uint i = old_size;i < new_size;i++)
 746                         (*thrd_inst_act_map)[i] = new inst_act_map_t(128);
 747         }
 748 }
 749
 750 /* Reset elements of thrd_inst_act_map when threads exit functions */
 751 void FuncNode::reset_inst_act_map(thread_id_t tid)
 752 {
 753         int thread_id = id_to_int(tid);
 754         SnapVector<inst_act_map_t *> * thrd_inst_act_map = history->getThrdInstActMap(func_id);
 755
 756         inst_act_map_t * map = (*thrd_inst_act_map)[thread_id];
 757         map->reset();
 758 }
 759
 760 void FuncNode::update_inst_act_map(thread_id_t tid, ModelAction * read_act)
 761 {
 762         int thread_id = id_to_int(tid);
 763         SnapVector<inst_act_map_t *> * thrd_inst_act_map = history->getThrdInstActMap(func_id);
 764
 765         inst_act_map_t * map = (*thrd_inst_act_map)[thread_id];
 766         FuncInst * read_inst = get_inst(read_act);
 767         map->put(read_inst, read_act);
 768 }
 769
 770 inst_act_map_t * FuncNode::get_inst_act_map(thread_id_t tid)
 771 {
 772         int thread_id = id_to_int(tid);
 773         SnapVector<inst_act_map_t *> * thrd_inst_act_map = history->getThrdInstActMap(func_id);
 774
 775         return (*thrd_inst_act_map)[thread_id];
 776 }
 777
 778 /* Add FuncNodes that this node may follow */
 779 void FuncNode::add_out_edge(FuncNode * other)
 780 {
 781         if ( !edge_table.contains(other) ) {
 782                 edge_table.put(other, OUT_EDGE);
 783                 out_edges.push_back(other);
 784                 return;
 785         }
 786
 787         edge_type_t edge = edge_table.get(other);
 788         if (edge == IN_EDGE) {
 789                 edge_table.put(other, BI_EDGE);
 790                 out_edges.push_back(other);
 791         }
 792 }
 793
 794 /* Compute the distance between this FuncNode and the target node.
 795  * Return -1 if the target node is unreachable or the actual distance
 796  * is greater than max_step.
 797  */
 798 int FuncNode::compute_distance(FuncNode * target, int max_step)
 799 {
 800         if (target == NULL)
 801                 return -1;
 802         else if (target == this)
 803                 return 0;
 804
 805         SnapList<FuncNode *> queue;
 806         HashTable<FuncNode *, int, uintptr_t, 0> distances(128);
 807
 808         queue.push_back(this);
 809         distances.put(this, 0);
 810
 811         while (!queue.empty()) {
 812                 FuncNode * curr = queue.front();
 813                 queue.pop_front();
 814                 int dist = distances.get(curr);
 815
 816                 if (max_step <= dist)
 817                         return -1;
 818
 819                 ModelList<FuncNode *> * outEdges = curr->get_out_edges();
 820                 mllnode<FuncNode *> * it;
 821                 for (it = outEdges->begin();it != NULL;it = it->getNext()) {
 822                         FuncNode * out_node = it->getVal();
 823
 824                         /* This node has not been visited before */
 825                         if ( !distances.contains(out_node) ) {
 826                                 if (out_node == target)
 827                                         return dist + 1;
 828
 829                                 queue.push_back(out_node);
 830                                 distances.put(out_node, dist + 1);
 831                         }
 832                 }
 833         }
 834
 835         /* Target node is unreachable */
 836         return -1;
 837 }
 838
 839 void FuncNode::add_failed_predicate(Predicate * pred)
 840 {
 841         failed_predicates.add(pred);
 842 }
 843
 844 /* Implement quick sort to sort leaves before assigning base scores */
 845 template<typename _Tp>
 846 static int partition(ModelVector<_Tp *> * arr, int low, int high)
 847 {
 848         unsigned int pivot = (*arr)[high] -> get_depth();
 849         int i = low - 1;
 850
 851         for (int j = low;j <= high - 1;j ++) {
 852                 if ( (*arr)[j] -> get_depth() < pivot ) {
 853                         i ++;
 854                         _Tp * tmp = (*arr)[i];
 855                         (*arr)[i] = (*arr)[j];
 856                         (*arr)[j] = tmp;
 857                 }
 858         }
 859
 860         _Tp * tmp = (*arr)[i + 1];
 861         (*arr)[i + 1] = (*arr)[high];
 862         (*arr)[high] = tmp;
 863
 864         return i + 1;
 865 }
 866
 867 /* Implement quick sort to sort leaves before assigning base scores */
 868 template<typename _Tp>
 869 static void quickSort(ModelVector<_Tp *> * arr, int low, int high)
 870 {
 871         if (low < high) {
 872                 int pi = partition(arr, low, high);
 873
 874                 quickSort(arr, low, pi - 1);
 875                 quickSort(arr, pi + 1, high);
 876         }
 877 }
 878
 879 void FuncNode::assign_initial_weight()
 880 {
 881         PredSetIter * it = predicate_leaves.iterator();
 882         leaves_tmp_storage.clear();
 883
 884         while (it->hasNext()) {
 885                 Predicate * pred = it->next();
 886                 double weight = 100.0 / sqrt(pred->get_expl_count() + pred->get_fail_count() + 1);
 887                 pred->set_weight(weight);
 888                 leaves_tmp_storage.push_back(pred);
 889         }
 890         delete it;
 891
 892         quickSort(&leaves_tmp_storage, 0, leaves_tmp_storage.size() - 1);
 893
 894         // assign scores for internal nodes;
 895         while ( !leaves_tmp_storage.empty() ) {
 896                 Predicate * leaf = leaves_tmp_storage.back();
 897                 leaves_tmp_storage.pop_back();
 898
 899                 Predicate * curr = leaf->get_parent();
 900                 while (curr != NULL) {
 901                         if (curr->get_weight() != 0) {
 902                                 // Has been exlpored
 903                                 break;
 904                         }
 905
 906                         ModelVector<Predicate *> * children = curr->get_children();
 907                         double weight_sum = 0;
 908                         bool has_unassigned_node = false;
 909
 910                         for (uint i = 0;i < children->size();i++) {
 911                                 Predicate * child = (*children)[i];
 912
 913                                 // If a child has unassigned weight
 914                                 double weight = child->get_weight();
 915                                 if (weight == 0) {
 916                                         has_unassigned_node = true;
 917                                         break;
 918                                 } else
 919                                         weight_sum += weight;
 920                         }
 921
 922                         if (!has_unassigned_node) {
 923                                 double average_weight = (double) weight_sum / (double) children->size();
 924                                 double weight = average_weight * pow(0.9, curr->get_depth());
 925                                 curr->set_weight(weight);
 926                         } else
 927                                 break;
 928
 929                         curr = curr->get_parent();
 930                 }
 931         }
 932 }
 933
 934 void FuncNode::update_predicate_tree_weight()
 935 {
 936         if (marker == 2) {
 937                 // Predicate tree is initially built
 938                 assign_initial_weight();
 939                 return;
 940         }
 941
 942         weight_debug_vec.clear();
 943
 944         PredSetIter * it = failed_predicates.iterator();
 945         while (it->hasNext()) {
 946                 Predicate * pred = it->next();
 947                 leaves_tmp_storage.push_back(pred);
 948         }
 949         delete it;
 950         failed_predicates.reset();
 951
 952         quickSort(&leaves_tmp_storage, 0, leaves_tmp_storage.size() - 1);
 953         for (uint i = 0;i < leaves_tmp_storage.size();i++) {
 954                 Predicate * pred = leaves_tmp_storage[i];
 955                 double weight = 100.0 / sqrt(pred->get_expl_count() + pred->get_fail_count() + 1);
 956                 pred->set_weight(weight);
 957         }
 958
 959         // Update weights in internal nodes
 960         while ( !leaves_tmp_storage.empty() ) {
 961                 Predicate * leaf = leaves_tmp_storage.back();
 962                 leaves_tmp_storage.pop_back();
 963
 964                 Predicate * curr = leaf->get_parent();
 965                 while (curr != NULL) {
 966                         ModelVector<Predicate *> * children = curr->get_children();
 967                         double weight_sum = 0;
 968                         bool has_unassigned_node = false;
 969
 970                         for (uint i = 0;i < children->size();i++) {
 971                                 Predicate * child = (*children)[i];
 972
 973                                 double weight = child->get_weight();
 974                                 if (weight != 0)
 975                                         weight_sum += weight;
 976                                 else if ( predicate_leaves.contains(child) ) {
 977                                         // If this child is a leaf
 978                                         double weight = 100.0 / sqrt(child->get_expl_count() + 1);
 979                                         child->set_weight(weight);
 980                                         weight_sum += weight;
 981                                 } else {
 982                                         has_unassigned_node = true;
 983                                         weight_debug_vec.push_back(child);      // For debugging purpose
 984                                         break;
 985                                 }
 986                         }
 987
 988                         if (!has_unassigned_node) {
 989                                 double average_weight = (double) weight_sum / (double) children->size();
 990                                 double weight = average_weight * pow(0.9, curr->get_depth());
 991                                 curr->set_weight(weight);
 992                         } else
 993                                 break;
 994
 995                         curr = curr->get_parent();
 996                 }
 997         }
 998
 999         for (uint i = 0;i < weight_debug_vec.size();i++) {
1000                 Predicate * tmp = weight_debug_vec[i];
1001                 ASSERT( tmp->get_weight() != 0 );
1002         }
1003 }
1004
1005 void FuncNode::print_predicate_tree()
1006 {
1007         model_print("digraph function_%s {\n", func_name);
1008         predicate_tree_entry->print_pred_subtree();
1009         predicate_tree_exit->print_predicate();
1010         model_print("}\n");     // end of graph
1011 }