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 //      ASSERT(inst->get_location() == act->get_location());
  74
  75         action_type inst_type = inst->get_type();
  76         action_type act_type = act->get_type();
  77
  78         // else if branch: an RMWRCAS action is converted to a RMW or READ action
  79         if (inst_type == act_type)
  80                 return inst;
  81         else if (inst_type == ATOMIC_RMWRCAS &&
  82                         (act_type == ATOMIC_RMW || act_type == ATOMIC_READ))
  83                 return inst;
  84
  85         return NULL;
  86 }
  87
  88
  89 void FuncNode::add_entry_inst(FuncInst * inst)
  90 {
  91         if (inst == NULL)
  92                 return;
  93
  94         mllnode<FuncInst *> * it;
  95         for (it = entry_insts.begin(); it != NULL; it = it->getNext()) {
  96                 if (inst == it->getVal())
  97                         return;
  98         }
  99
 100         entry_insts.push_back(inst);
 101 }
 102
 103 /**
 104  * @brief Convert ModelAdtion list to FuncInst list
 105  * @param act_list A list of ModelActions
 106  */
 107 void FuncNode::update_tree(action_list_t * act_list)
 108 {
 109         if (act_list == NULL)
 110                 return;
 111         else if (act_list->size() == 0)
 112                 return;
 113
 114         /* build inst_list from act_list for later processing */
 115         func_inst_list_t inst_list;
 116         action_list_t read_act_list;
 117         HashTable<ModelAction *, FuncInst *, uintptr_t, 4> act_inst_map;
 118
 119         for (sllnode<ModelAction *> * it = act_list->begin(); it != NULL; it = it->getNext()) {
 120                 ModelAction * act = it->getVal();
 121                 FuncInst * func_inst = get_inst(act);
 122
 123                 if (func_inst == NULL)
 124                         continue;
 125
 126                 inst_list.push_back(func_inst);
 127
 128 //              model_print("position: %s ", act->get_position());
 129 //              act->print();
 130
 131                 if (func_inst->is_read()) {
 132                         read_act_list.push_back(act);
 133                         act_inst_map.put(act, func_inst);
 134                 }
 135         }
 136
 137         update_inst_tree(&inst_list);
 138         update_predicate_tree(&read_act_list, &act_inst_map);
 139 }
 140
 141 /**
 142  * @brief Link FuncInsts in inst_list  - add one FuncInst to another's predecessors and successors
 143  * @param inst_list A list of FuncInsts
 144  */
 145 void FuncNode::update_inst_tree(func_inst_list_t * inst_list)
 146 {
 147         if (inst_list == NULL)
 148                 return;
 149         else if (inst_list->size() == 0)
 150                 return;
 151
 152         /* start linking */
 153         sllnode<FuncInst *>* it = inst_list->begin();
 154         sllnode<FuncInst *>* prev;
 155
 156         /* add the first instruction to the list of entry insts */
 157         FuncInst * entry_inst = it->getVal();
 158         add_entry_inst(entry_inst);
 159
 160         it = it->getNext();
 161         while (it != NULL) {
 162                 prev = it->getPrev();
 163
 164                 FuncInst * prev_inst = prev->getVal();
 165                 FuncInst * curr_inst = it->getVal();
 166
 167                 prev_inst->add_succ(curr_inst);
 168                 curr_inst->add_pred(prev_inst);
 169
 170                 it = it->getNext();
 171         }
 172 }
 173
 174 /* @param tid thread id
 175  * Store the values read by atomic read actions into thrd_read_map */
 176 void FuncNode::store_read(ModelAction * act, uint32_t tid)
 177 {
 178         ASSERT(act);
 179
 180         void * location = act->get_location();
 181         uint64_t read_from_val = act->get_reads_from_value();
 182
 183         /* resize and initialize */
 184         uint32_t old_size = thrd_read_map.size();
 185         if (old_size <= tid) {
 186                 thrd_read_map.resize(tid + 1);
 187                 for (uint32_t i = old_size; i < tid + 1;i++)
 188                         thrd_read_map[i] = new read_map_t();
 189         }
 190
 191         read_map_t * read_map = thrd_read_map[tid];
 192         read_map->put(location, read_from_val);
 193
 194         /* Store the memory locations where atomic reads happen */
 195         // read_locations.add(location);
 196 }
 197
 198 uint64_t FuncNode::query_last_read(void * location, uint32_t tid)
 199 {
 200         if (thrd_read_map.size() <= tid)
 201                 return 0xdeadbeef;
 202
 203         read_map_t * read_map = thrd_read_map[tid];
 204
 205         /* last read value not found */
 206         if ( !read_map->contains(location) )
 207                 return 0xdeadbeef;
 208
 209         uint64_t read_val = read_map->get(location);
 210         return read_val;
 211 }
 212
 213 /* @param tid thread id
 214  * Reset read map for a thread. This function shall only be called
 215  * when a thread exits a function
 216  */
 217 void FuncNode::clear_read_map(uint32_t tid)
 218 {
 219         if (thrd_read_map.size() <= tid)
 220                 return;
 221
 222         thrd_read_map[tid]->reset();
 223 }
 224
 225 void FuncNode::update_predicate_tree(action_list_t * act_list, HashTable<ModelAction *, FuncInst *, uintptr_t, 4> * act_inst_map)
 226 {
 227         if (act_list == NULL || act_list->size() == 0)
 228                 return;
 229 /*
 230         if (predicate_tree_initialized) {
 231                 return;
 232         }
 233         predicate_tree_initialized = true;
 234 */
 235         /* map a FuncInst to the parent of its predicate */
 236         HashTable<FuncInst *, Predicate *, uintptr_t, 0> inst_pred_map(128);
 237         HashTable<void *, ModelAction *, uintptr_t, 0> loc_act_map(128);
 238
 239         sllnode<ModelAction *> *it = act_list->begin();
 240         Predicate * curr_pred = predicate_tree_entry;
 241
 242         while (it != NULL) {
 243                 ModelAction * next_act = it->getVal();
 244                 FuncInst * next_inst = act_inst_map->get(next_act);
 245                 Predicate * old_pred = curr_pred;
 246
 247                 bool branch_found = follow_branch(&curr_pred, next_inst, next_act, &loc_act_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(next_inst)) {
 258                                 back_pred = inst_pred_map.get(next_inst);
 259                                 curr_pred->set_backedge(back_pred);
 260                                 curr_pred = back_pred;
 261                                 continue;
 262                         }
 263                 }
 264
 265                 if (!inst_pred_map.contains(next_inst))
 266                         inst_pred_map.put(next_inst, old_pred);
 267
 268                 if (!branch_found) {
 269                         if ( loc_act_map.contains(next_act->get_location()) ) {
 270                                 Predicate * new_pred1 = new Predicate(next_inst);
 271                                 new_pred1->add_predicate(EQUALITY, next_act->get_location(), true);
 272
 273                                 Predicate * new_pred2 = new Predicate(next_inst);
 274                                 new_pred2->add_predicate(EQUALITY, next_act->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                                 ModelAction * last_act = loc_act_map.get(next_act->get_location());
 282                                 uint64_t last_read = last_act->get_reads_from_value();
 283                                 uint64_t next_read = next_act->get_reads_from_value();
 284
 285                                 if ( last_read == next_read )
 286                                         curr_pred = new_pred1;
 287                                 else
 288                                         curr_pred = new_pred2;
 289                         } else {
 290                                 Predicate * new_pred = new Predicate(next_inst);
 291                                 curr_pred->add_child(new_pred);
 292                                 //new_pred->add_parent(curr_pred);
 293
 294                                 curr_pred = new_pred;
 295                         }
 296                 }
 297
 298                 loc_act_map.put(next_act->get_location(), next_act);
 299                 it = it->getNext();
 300         }
 301
 302 //      model_print("function %s\n", func_name);
 303 //      print_predicate_tree();
 304 }
 305
 306 /* Given curr_pred and next_inst, find the branch following curr_pred that contains next_inst and the correct predicate
 307  * @return true if branch found, false otherwise.
 308  */
 309 bool FuncNode::follow_branch(Predicate ** curr_pred, FuncInst * next_inst, ModelAction * next_act,
 310         HashTable<void *, ModelAction *, uintptr_t, 0> * loc_act_map)
 311 {
 312         /* check if a branch with func_inst and corresponding predicate exists */
 313         bool branch_found = false;
 314         ModelVector<Predicate *> * branches = (*curr_pred)->get_children();
 315         for (uint i = 0; i < branches->size(); i++) {
 316                 Predicate * branch = (*branches)[i];
 317                 if (branch->get_func_inst() != next_inst)
 318                         continue;
 319
 320                 PredExprSet * pred_expressions = branch->get_pred_expressions();
 321
 322                 /* no predicate, follow the only branch */
 323                 if (pred_expressions->getSize() == 0) {
 324 //                      model_print("no predicate exists: "); next_inst->print();
 325                         *curr_pred = branch;
 326                         branch_found = true;
 327                         break;
 328                 }
 329
 330                 PredExprSetIter * pred_expr_it = pred_expressions->iterator();
 331                 while (pred_expr_it->hasNext()) {
 332                         pred_expr * pred_expression = pred_expr_it->next();
 333                         uint64_t last_read, next_read;
 334                         ModelAction * last_act;
 335                         bool equality;
 336
 337                         switch(pred_expression->token) {
 338                                 case EQUALITY:
 339                                         last_act = loc_act_map->get(next_act->get_location());
 340                                         last_read = last_act->get_reads_from_value();
 341                                         next_read = next_act->get_reads_from_value();
 342
 343                                         equality = (last_read == next_read);
 344
 345                                         if (equality == pred_expression->value) {
 346                                                 *curr_pred = branch;
 347 //                                              model_print("predicate: token: %d, location: %p, value: %d - ", pred_expression->token, pred_expression->location, pred_expression->value); next_inst->print();
 348                                                 branch_found = true;
 349                                         }
 350                                         break;
 351                                 case NULLITY:
 352                                         break;
 353                                 default:
 354                                         model_print("unkown predicate token\n");
 355                                         break;
 356                         }
 357                 }
 358
 359         }
 360
 361         return branch_found;
 362 }
 363
 364 void FuncNode::print_predicate_tree()
 365 {
 366         model_print("digraph function_%s {\n", func_name);
 367         predicate_tree_entry->print_pred_subtree();
 368         model_print("}\n");     // end of graph
 369 }
 370
 371 /* @param tid thread id
 372  * Print the values read by the last read actions for each memory location
 373  */
 374 /*
 375 void FuncNode::print_last_read(uint32_t tid)
 376 {
 377         ASSERT(thrd_read_map.size() > tid);
 378         read_map_t * read_map = thrd_read_map[tid];
 379
 380         mllnode<void *> * it;
 381         for (it = read_locations.begin();it != NULL;it=it->getNext()) {
 382                 if ( !read_map->contains(it->getVal()) )
 383                         break;
 384
 385                 uint64_t read_val = read_map->get(it->getVal());
 386                 model_print("last read of thread %d at %p: 0x%x\n", tid, it->getVal(), read_val);
 387         }
 388 }
 389 */