funcnode.cc

   1 #include "funcnode.h"
   2
   3 FuncNode::FuncNode() :
   4         predicate_tree_initialized(false),
   5         predicate_tree_entry(new Predicate(NULL, true)),
   6         func_inst_map(),
   7         inst_list(),
   8         entry_insts(),
   9         thrd_read_map()
  10 {}
  11
  12 /* Check whether FuncInst with the same type, position, and location
  13  * as act has been added to func_inst_map or not. If not, add it.
  14  *
  15  * Note: currently, actions with the same position are filtered out by process_action,
  16  * so the collision list of FuncInst is not used. May remove it later.
  17  */
  18 void FuncNode::add_inst(ModelAction *act)
  19 {
  20         ASSERT(act);
  21         const char * position = act->get_position();
  22
  23         /* THREAD* actions, ATOMIC_LOCK, ATOMIC_TRYLOCK, and ATOMIC_UNLOCK
  24          * actions are not tagged with their source line numbers
  25          */
  26         if (position == NULL)
  27                 return;
  28
  29         if ( func_inst_map.contains(position) ) {
  30                 FuncInst * inst = func_inst_map.get(position);
  31
  32                 ASSERT(inst->get_type() == act->get_type());
  33                 if (inst->get_location() != act->get_location())
  34                         inst->not_single_location();
  35
  36                 return;
  37         }
  38
  39         FuncInst * func_inst = new FuncInst(act, this);
  40
  41         func_inst_map.put(position, func_inst);
  42         inst_list.push_back(func_inst);
  43 }
  44
  45 /* Get the FuncInst with the same type, position, and location
  46  * as act
  47  *
  48  * @return FuncInst with the same type, position, and location as act */
  49 FuncInst * FuncNode::get_inst(ModelAction *act)
  50 {
  51         ASSERT(act);
  52         const char * position = act->get_position();
  53
  54         /* THREAD* actions, ATOMIC_LOCK, ATOMIC_TRYLOCK, and ATOMIC_UNLOCK
  55          * actions are not tagged with their source line numbers
  56          */
  57         if (position == NULL)
  58                 return NULL;
  59
  60         FuncInst * inst = func_inst_map.get(position);
  61         if (inst == NULL)
  62                 return NULL;
  63
  64         action_type inst_type = inst->get_type();
  65         action_type act_type = act->get_type();
  66
  67         // else if branch: an RMWRCAS action is converted to a RMW or READ action
  68         if (inst_type == act_type)
  69                 return inst;
  70         else if (inst_type == ATOMIC_RMWRCAS &&
  71                         (act_type == ATOMIC_RMW || act_type == ATOMIC_READ))
  72                 return inst;
  73
  74         return NULL;
  75 }
  76
  77
  78 void FuncNode::add_entry_inst(FuncInst * inst)
  79 {
  80         if (inst == NULL)
  81                 return;
  82
  83         mllnode<FuncInst *> * it;
  84         for (it = entry_insts.begin(); it != NULL; it = it->getNext()) {
  85                 if (inst == it->getVal())
  86                         return;
  87         }
  88
  89         entry_insts.push_back(inst);
  90 }
  91
  92 /**
  93  * @brief Convert ModelAdtion list to FuncInst list
  94  * @param act_list A list of ModelActions
  95  */
  96 void FuncNode::update_tree(action_list_t * act_list)
  97 {
  98         if (act_list == NULL)
  99                 return;
 100         else if (act_list->size() == 0)
 101                 return;
 102
 103         /* build inst_list from act_list for later processing */
 104         func_inst_list_t inst_list;
 105         action_list_t read_act_list;
 106
 107         for (sllnode<ModelAction *> * it = act_list->begin(); it != NULL; it = it->getNext()) {
 108                 ModelAction * act = it->getVal();
 109                 FuncInst * func_inst = get_inst(act);
 110
 111                 if (func_inst == NULL)
 112                         continue;
 113
 114                 inst_list.push_back(func_inst);
 115
 116 //              model_print("position: %s ", act->get_position());
 117 //              act->print();
 118
 119                 if (func_inst->is_read())
 120                         read_act_list.push_back(act);
 121         }
 122
 123         model_print("function %s\n", func_name);
 124         update_inst_tree(&inst_list);
 125         update_predicate_tree(&read_act_list);
 126         deep_update(predicate_tree_entry);
 127
 128         print_predicate_tree();
 129 }
 130
 131 /**
 132  * @brief Link FuncInsts in inst_list  - add one FuncInst to another's predecessors and successors
 133  * @param inst_list A list of FuncInsts
 134  */
 135 void FuncNode::update_inst_tree(func_inst_list_t * inst_list)
 136 {
 137         if (inst_list == NULL)
 138                 return;
 139         else if (inst_list->size() == 0)
 140                 return;
 141
 142         /* start linking */
 143         sllnode<FuncInst *>* it = inst_list->begin();
 144         sllnode<FuncInst *>* prev;
 145
 146         /* add the first instruction to the list of entry insts */
 147         FuncInst * entry_inst = it->getVal();
 148         add_entry_inst(entry_inst);
 149
 150         it = it->getNext();
 151         while (it != NULL) {
 152                 prev = it->getPrev();
 153
 154                 FuncInst * prev_inst = prev->getVal();
 155                 FuncInst * curr_inst = it->getVal();
 156
 157                 prev_inst->add_succ(curr_inst);
 158                 curr_inst->add_pred(prev_inst);
 159
 160                 it = it->getNext();
 161         }
 162 }
 163
 164 /* @param tid thread id
 165  * Store the values read by atomic read actions into thrd_read_map */
 166 void FuncNode::store_read(ModelAction * act, uint32_t tid)
 167 {
 168         ASSERT(act);
 169
 170         void * location = act->get_location();
 171         uint64_t read_from_val = act->get_reads_from_value();
 172
 173         /* resize and initialize */
 174         uint32_t old_size = thrd_read_map.size();
 175         if (old_size <= tid) {
 176                 thrd_read_map.resize(tid + 1);
 177                 for (uint32_t i = old_size; i < tid + 1;i++)
 178                         thrd_read_map[i] = new read_map_t();
 179         }
 180
 181         read_map_t * read_map = thrd_read_map[tid];
 182         read_map->put(location, read_from_val);
 183
 184         /* Store the memory locations where atomic reads happen */
 185         // read_locations.add(location);
 186 }
 187
 188 uint64_t FuncNode::query_last_read(void * location, uint32_t tid)
 189 {
 190         if (thrd_read_map.size() <= tid)
 191                 return VALUE_NONE;
 192
 193         read_map_t * read_map = thrd_read_map[tid];
 194
 195         /* last read value not found */
 196         if ( !read_map->contains(location) )
 197                 return VALUE_NONE;
 198
 199         uint64_t read_val = read_map->get(location);
 200         return read_val;
 201 }
 202
 203 /* @param tid thread id
 204  * Reset read map for a thread. This function shall only be called
 205  * when a thread exits a function
 206  */
 207 void FuncNode::clear_read_map(uint32_t tid)
 208 {
 209         if (thrd_read_map.size() <= tid)
 210                 return;
 211
 212         thrd_read_map[tid]->reset();
 213 }
 214
 215 void FuncNode::update_predicate_tree(action_list_t * act_list)
 216 {
 217         if (act_list == NULL || act_list->size() == 0)
 218                 return;
 219 /*
 220         if (predicate_tree_initialized) {
 221                 return;
 222         }
 223         predicate_tree_initialized = true;
 224 */
 225         /* map a FuncInst to the parent of its predicate */
 226         HashTable<FuncInst *, Predicate *, uintptr_t, 0> inst_pred_map(128);
 227         HashTable<void *, ModelAction *, uintptr_t, 0> loc_act_map(128);
 228
 229         sllnode<ModelAction *> *it = act_list->begin();
 230         Predicate * curr_pred = predicate_tree_entry;
 231
 232         while (it != NULL) {
 233                 ModelAction * next_act = it->getVal();
 234                 FuncInst * next_inst = get_inst(next_act);
 235                 Predicate * old_pred = curr_pred;
 236
 237                 bool branch_found = follow_branch(&curr_pred, next_inst, next_act, &loc_act_map);
 238
 239                 // check back edges
 240                 if (!branch_found) {
 241                         Predicate * back_pred = curr_pred->get_backedge();
 242                         if (back_pred != NULL) {
 243                                 curr_pred = back_pred;
 244                                 continue;
 245                         }
 246
 247                         if (inst_pred_map.contains(next_inst)) {
 248                                 back_pred = inst_pred_map.get(next_inst);
 249                                 curr_pred->set_backedge(back_pred);
 250                                 curr_pred = back_pred;
 251                                 continue;
 252                         }
 253                 }
 254
 255                 if (!inst_pred_map.contains(next_inst))
 256                         inst_pred_map.put(next_inst, old_pred);
 257
 258                 if (!branch_found) {
 259                         if ( loc_act_map.contains(next_act->get_location()) ) {
 260                                 Predicate * new_pred1 = new Predicate(next_inst);
 261                                 new_pred1->add_predicate(EQUALITY, next_act->get_location(), true);
 262
 263                                 Predicate * new_pred2 = new Predicate(next_inst);
 264                                 new_pred2->add_predicate(EQUALITY, next_act->get_location(), false);
 265
 266                                 curr_pred->add_child(new_pred1);
 267                                 curr_pred->add_child(new_pred2);
 268                                 new_pred1->set_parent(curr_pred);
 269                                 new_pred2->set_parent(curr_pred);
 270
 271                                 ModelAction * last_act = loc_act_map.get(next_act->get_location());
 272                                 uint64_t last_read = last_act->get_reads_from_value();
 273                                 uint64_t next_read = next_act->get_reads_from_value();
 274
 275                                 if ( last_read == next_read )
 276                                         curr_pred = new_pred1;
 277                                 else
 278                                         curr_pred = new_pred2;
 279                         } else {
 280                                 Predicate * new_pred = new Predicate(next_inst);
 281                                 curr_pred->add_child(new_pred);
 282                                 new_pred->set_parent(curr_pred);
 283
 284                                 curr_pred = new_pred;
 285                         }
 286                 }
 287
 288                 loc_act_map.put(next_act->get_location(), next_act);
 289                 it = it->getNext();
 290         }
 291 }
 292
 293 void FuncNode::deep_update(Predicate * curr_pred)
 294 {
 295         FuncInst * func_inst = curr_pred->get_func_inst();
 296         if (func_inst != NULL && !func_inst->is_single_location()) {
 297                 bool has_null_pred = false;
 298                 PredExprSet * pred_expressions = curr_pred->get_pred_expressions();
 299                 PredExprSetIter * pred_expr_it = pred_expressions->iterator();
 300                 while (pred_expr_it->hasNext()) {
 301                         pred_expr * pred_expression = pred_expr_it->next();
 302                         if (pred_expression->token == NULLITY) {
 303                                 has_null_pred = true;
 304                                 break;
 305                         }
 306                 }
 307
 308                 if (!has_null_pred) {
 309 //                      func_inst->print();
 310                         Predicate * parent = curr_pred->get_parent();
 311                         curr_pred->add_predicate(NULLITY, NULL, 0);
 312
 313                         Predicate * another_branch = new Predicate(func_inst);
 314                         another_branch->add_predicate(NULLITY, NULL, 1);
 315                         parent->add_child(another_branch);
 316 //                      another_branch.add_children(i);
 317                 }
 318         }
 319
 320         ModelVector<Predicate *> * branches = curr_pred->get_children();
 321         for (uint i = 0; i < branches->size(); i++) {
 322                 Predicate * branch = (*branches)[i];
 323                 deep_update(branch);
 324         }
 325 }
 326
 327 /* Given curr_pred and next_inst, find the branch following curr_pred that contains next_inst and the correct predicate
 328  * @return true if branch found, false otherwise.
 329  */
 330 bool FuncNode::follow_branch(Predicate ** curr_pred, FuncInst * next_inst, ModelAction * next_act,
 331         HashTable<void *, ModelAction *, uintptr_t, 0> * loc_act_map)
 332 {
 333         /* check if a branch with func_inst and corresponding predicate exists */
 334         bool branch_found = false;
 335         ModelVector<Predicate *> * branches = (*curr_pred)->get_children();
 336         for (uint i = 0; i < branches->size(); i++) {
 337                 Predicate * branch = (*branches)[i];
 338                 if (branch->get_func_inst() != next_inst)
 339                         continue;
 340
 341                 PredExprSet * pred_expressions = branch->get_pred_expressions();
 342
 343                 /* no predicate, follow the only branch */
 344                 if (pred_expressions->getSize() == 0) {
 345                         *curr_pred = branch;
 346                         branch_found = true;
 347                         break;
 348                 }
 349
 350                 PredExprSetIter * pred_expr_it = pred_expressions->iterator();
 351                 while (pred_expr_it->hasNext()) {
 352                         pred_expr * pred_expression = pred_expr_it->next();
 353                         uint64_t last_read, next_read;
 354                         ModelAction * last_act;
 355                         bool equality;
 356
 357                         switch(pred_expression->token) {
 358                                 case EQUALITY:
 359                                         last_act = loc_act_map->get(next_act->get_location());
 360                                         last_read = last_act->get_reads_from_value();
 361                                         next_read = next_act->get_reads_from_value();
 362
 363                                         equality = (last_read == next_read);
 364                                         if (equality == pred_expression->value) {
 365                                                 *curr_pred = branch;
 366 //                                              model_print("predicate: token: %d, location: %p, value: %d - ", pred_expression->token, pred_expression->location, pred_expression->value); next_inst->print();
 367                                                 branch_found = true;
 368                                         }
 369                                         break;
 370                                 case NULLITY:
 371                                         next_read = next_act->get_reads_from_value();
 372                                         equality = ((void*)next_read == NULL);
 373                                         //model_print("%s ", next_act->get_position()); next_act->print();
 374                                         if (equality == pred_expression->value) {
 375                                                 *curr_pred = branch;
 376                                                 branch_found = true;
 377                                         }
 378                                         break;
 379                                 default:
 380                                         model_print("unkown predicate token\n");
 381                                         break;
 382                         }
 383                 }
 384
 385         }
 386
 387         return branch_found;
 388 }
 389
 390 void FuncNode::print_predicate_tree()
 391 {
 392         model_print("digraph function_%s {\n", func_name);
 393         predicate_tree_entry->print_pred_subtree();
 394         model_print("}\n");     // end of graph
 395 }
 396
 397 /* @param tid thread id
 398  * Print the values read by the last read actions for each memory location
 399  */
 400 /*
 401 void FuncNode::print_last_read(uint32_t tid)
 402 {
 403         ASSERT(thrd_read_map.size() > tid);
 404         read_map_t * read_map = thrd_read_map[tid];
 405
 406         mllnode<void *> * it;
 407         for (it = read_locations.begin();it != NULL;it=it->getNext()) {
 408                 if ( !read_map->contains(it->getVal()) )
 409                         break;
 410
 411                 uint64_t read_val = read_map->get(it->getVal());
 412                 model_print("last read of thread %d at %p: 0x%x\n", tid, it->getVal(), read_val);
 413         }
 414 }
 415 */