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