funcnode.cc

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