fix mutex_trylock bug
[c11tester.git] / newfuzzer.cc
index e09175ce227ce1e17f87204ad08a686c743e1d1b..7d4e8b1810880f600393e76f5618af8dc2b9516b 100644 (file)
 #include "newfuzzer.h"
 #include "threads-model.h"
-#include "model.h"
 #include "action.h"
-#include "execution.h"
+#include "history.h"
 #include "funcnode.h"
+#include "funcinst.h"
+#include "concretepredicate.h"
+#include "waitobj.h"
+
+#include "model.h"
+#include "schedule.h"
+#include "execution.h"
 
 NewFuzzer::NewFuzzer() :
        thrd_last_read_act(),
-       thrd_curr_pred(),
+       thrd_last_func_inst(),
+       available_branches_tmp_storage(),
        thrd_selected_child_branch(),
-       thrd_pruned_writes()
+       thrd_pruned_writes(),
+       paused_thread_list(),
+       paused_thread_table(128),
+       dist_info_vec()
 {}
 
 /**
  * @brief Register the ModelHistory and ModelExecution engine
  */
-void NewFuzzer::register_engine(ModelHistory * history, ModelExecution *execution)
+void NewFuzzer::register_engine(ModelChecker *_model, ModelExecution *execution)
 {
-       this->history = history;
+       this->history = _model->get_history();
        this->execution = execution;
 }
 
 int NewFuzzer::selectWrite(ModelAction *read, SnapVector<ModelAction *> * rf_set)
 {
+       return random() % rf_set->size();
+
        thread_id_t tid = read->get_tid();
        int thread_id = id_to_int(tid);
 
-       if (thrd_last_read_act.size() <= (uint) thread_id)
+       if (thrd_last_read_act.size() <= (uint) thread_id) {
                thrd_last_read_act.resize(thread_id + 1);
+               thrd_last_func_inst.resize(thread_id + 1);
+       }
 
        // A new read action is encountered, select a random child branch of current predicate
        if (read != thrd_last_read_act[thread_id]) {
-               thrd_last_read_act[thread_id] = read;
-
-               SnapVector<func_id_list_t> * thrd_func_list = execution->get_thrd_func_list();
-               uint32_t func_id = (*thrd_func_list)[thread_id].back();
-               FuncNode * func_node = history->get_func_node(func_id);
-               inst_act_map_t * inst_act_map = func_node->get_inst_act_map(tid);
+               FuncNode * func_node = history->get_curr_func_node(tid);
                Predicate * curr_pred = func_node->get_predicate_tree_position(tid);
                FuncInst * read_inst = func_node->get_inst(read);
 
-               Predicate * selected_branch = selectBranch(tid, curr_pred, read_inst);
-               prune_writes(tid, selected_branch, rf_set, inst_act_map);
+               if (curr_pred != NULL)  {
+                       Predicate * selected_branch = NULL;
+
+                       if (check_branch_inst(curr_pred, read_inst, rf_set))
+                               selected_branch = selectBranch(tid, curr_pred, read_inst);
+                       else {
+                               // no child of curr_pred matches read_inst, check back edges
+                               PredSet * back_edges = curr_pred->get_backedges();
+                               PredSetIter * it = back_edges->iterator();
+
+                               while (it->hasNext()) {
+                                       curr_pred = it->next();
+                                       if (check_branch_inst(curr_pred, read_inst, rf_set)) {
+                                               selected_branch = selectBranch(tid, curr_pred, read_inst);
+                                               break;
+                                       }
+                               }
+
+                               delete it;
+                       }
+
+                       thrd_selected_child_branch[thread_id] = selected_branch;
+                       prune_writes(tid, selected_branch, rf_set);
+               }
+
+               thrd_last_read_act[thread_id] = read;
+               thrd_last_func_inst[thread_id] = read_inst;
        }
 
-       // TODO: make this thread sleep if no write satisfies the chosen predicate
-       // if no read satisfies the selected predicate
-       if ( rf_set->size() == 0 ) {
+       // The chosen branch fails, reselect new branches
+       while ( rf_set->size() == 0 ) {
+               Predicate * selected_branch = get_selected_child_branch(tid);
+               FuncNode * func_node = history->get_curr_func_node(tid);
+
+               // Increment failure count
+               selected_branch->incr_fail_count();
+               func_node->add_predicate_to_trace(tid, selected_branch);        // For updating predicate weight
+
+               //model_print("the %d read action of thread %d at %p is unsuccessful\n", read->get_seq_number(), read_thread->get_id(), read->get_location());
+
                SnapVector<ModelAction *> * pruned_writes = thrd_pruned_writes[thread_id];
-               for (uint i = 0; i < pruned_writes->size(); i++)
+               for (uint i = 0;i < pruned_writes->size();i++) {
                        rf_set->push_back( (*pruned_writes)[i] );
+               }
+
+               // Reselect a predicate and prune writes
+               Predicate * curr_pred = selected_branch->get_parent();
+               FuncInst * read_inst = thrd_last_func_inst[thread_id];
+               selected_branch = selectBranch(tid, curr_pred, read_inst);
+               thrd_selected_child_branch[thread_id] = selected_branch;
+
+               prune_writes(tid, selected_branch, rf_set);
+
+               ASSERT(selected_branch);
        }
 
-       ASSERT(rf_set->size() != 0);
        int random_index = random() % rf_set->size();
 
        return random_index;
 }
 
-/* Select a random branch from the children of curr_pred 
+/* Check if children of curr_pred match read_inst.
+ * @return False if no child matches read_inst
+ */
+bool NewFuzzer::check_branch_inst(Predicate * curr_pred, FuncInst * read_inst,
+                                                                                                                                       SnapVector<ModelAction *> * rf_set)
+{
+       available_branches_tmp_storage.clear();
+
+       ASSERT(!rf_set->empty());
+       if (curr_pred == NULL || read_inst == NULL)
+               return false;
+
+       ModelVector<Predicate *> * children = curr_pred->get_children();
+       bool any_child_match = false;
+
+       /* Iterate over all predicate children */
+       for (uint i = 0;i < children->size();i++) {
+               Predicate * branch = (*children)[i];
+
+               /* The children predicates may have different FuncInsts */
+               if (branch->get_func_inst() == read_inst) {
+                       any_child_match = true;
+                       branch->incr_total_checking_count();
+                       available_branches_tmp_storage.push_back(branch);
+               }
+       }
+
+       return any_child_match;
+}
+
+/* Select a random branch from the children of curr_pred
  * @return The selected branch
  */
 Predicate * NewFuzzer::selectBranch(thread_id_t tid, Predicate * curr_pred, FuncInst * read_inst)
@@ -72,27 +154,54 @@ Predicate * NewFuzzer::selectBranch(thread_id_t tid, Predicate * curr_pred, Func
                return NULL;
        }
 
-       ModelVector<Predicate *> * children = curr_pred->get_children();
-       SnapVector<Predicate *> branches;
-
-       for (uint i = 0; i < children->size(); i++) {
-               Predicate * child = (*children)[i];
-               if (child->get_func_inst() == read_inst)
-                       branches.push_back(child);
-       }
-
        // predicate children have not been generated
-       if (branches.size() == 0) {
+       if (available_branches_tmp_storage.size() == 0) {
                thrd_selected_child_branch[thread_id] = NULL;
                return NULL;
        }
 
-       // randomly select a branch
-       int random_index = random() % branches.size();
-       Predicate * random_branch = branches[ random_index ];
-       thrd_selected_child_branch[thread_id] = random_branch;
+       int index = choose_branch_index(&available_branches_tmp_storage);
+       Predicate * selected_branch = available_branches_tmp_storage[ index ];
 
-       return random_branch;
+       /* Remove the chosen branch from vec in case that this
+        * branch fails and need to choose another one */
+       available_branches_tmp_storage[index] = available_branches_tmp_storage.back();
+       available_branches_tmp_storage.pop_back();
+
+       return selected_branch;
+}
+
+/**
+ * @brief Select a branch from the given predicate branch
+ */
+int NewFuzzer::choose_branch_index(SnapVector<Predicate *> * branches)
+{
+       if (branches->size() == 1)
+               return 0;
+
+       double total_weight = 0;
+       SnapVector<double> weights;
+       for (uint i = 0;i < branches->size();i++) {
+               Predicate * branch = (*branches)[i];
+               double weight = branch->get_weight();
+               total_weight += weight;
+               weights.push_back(weight);
+       }
+
+       double prob = (double) random() / RAND_MAX;
+       double prob_sum = 0;
+       int index = 0;
+
+       for (uint i = 0;i < weights.size();i++) {
+               index = i;
+               prob_sum += (double) (weights[i] / total_weight);
+               if (prob_sum > prob) {
+                       break;
+               }
+       }
+
+       return index;
+//     return random() % branches->size();
 }
 
 Predicate * NewFuzzer::get_selected_child_branch(thread_id_t tid)
@@ -104,13 +213,12 @@ Predicate * NewFuzzer::get_selected_child_branch(thread_id_t tid)
        return thrd_selected_child_branch[thread_id];
 }
 
-/* Remove writes from the rf_set that do not satisfie the selected predicate, 
+/* Remove writes from the rf_set that do not satisfie the selected predicate,
  * and store them in thrd_pruned_writes
  *
  * @return true if rf_set is pruned
  */
-bool NewFuzzer::prune_writes(thread_id_t tid, Predicate * pred,
-       SnapVector<ModelAction *> * rf_set, inst_act_map_t * inst_act_map)
+bool NewFuzzer::prune_writes(thread_id_t tid, Predicate * pred, SnapVector<ModelAction *> * rf_set)
 {
        if (pred == NULL)
                return false;
@@ -124,65 +232,220 @@ bool NewFuzzer::prune_writes(thread_id_t tid, Predicate * pred,
        if (thrd_pruned_writes.size() <= (uint) thread_id) {
                uint new_size = thread_id + 1;
                thrd_pruned_writes.resize(new_size);
-               for (uint i = old_size; i < new_size; i++)
+               for (uint i = old_size;i < new_size;i++)
                        thrd_pruned_writes[i] = new SnapVector<ModelAction *>();
        }
        SnapVector<ModelAction *> * pruned_writes = thrd_pruned_writes[thread_id];
        pruned_writes->clear(); // clear the old pruned_writes set
 
        bool pruned = false;
-       uint index = 0;
-       while ( index < rf_set->size() ) {
-               ModelAction * write_act = (*rf_set)[index];
+       uint rf_index = 0;
+
+       while ( rf_index < rf_set->size() ) {
+               ModelAction * write_act = (*rf_set)[rf_index];
+               uint64_t write_val = write_act->get_write_value();
+               bool no_predicate = false;
                bool satisfy_predicate = true;
 
+               // Check if the write value satisfies the predicates
                PredExprSetIter * pred_expr_it = pred_expressions->iterator();
                while (pred_expr_it->hasNext()) {
                        struct pred_expr * expression = pred_expr_it->next();
-                       uint64_t write_val = write_act->get_write_value();
                        bool equality;
 
-                       // No predicate, return false
-                       if (expression->token == NOPREDICATE)
-                               return pruned;
-
-                       switch(expression->token) {
-                               case EQUALITY:
-                                       FuncInst * to_be_compared;
-                                       ModelAction * last_act;
-                                       uint64_t last_read;
-
-                                       to_be_compared = expression->func_inst;
-                                       last_act = inst_act_map->get(to_be_compared);
-                                       last_read = last_act->get_reads_from_value();
-
-                                       equality = (write_val == last_read);
-                                       if (equality != expression->value)
-                                               satisfy_predicate = false;
-                                       break;
-                               case NULLITY:
-                                       equality = ((void*)write_val == NULL);
-                                       if (equality != expression->value)
-                                               satisfy_predicate = false;
-                                       break;
-                               default:
-                                       model_print("unknown predicate token\n");
-                                       break;
+                       switch (expression->token) {
+                       case NOPREDICATE:
+                               no_predicate = true;
+                               break;
+                       case EQUALITY:
+                               FuncInst * to_be_compared;
+                               FuncNode * func_node;
+                               uint64_t last_read;
+
+                               to_be_compared = expression->func_inst;
+                               func_node = history->get_curr_func_node(tid);
+                               last_read = func_node->get_associated_read(tid, to_be_compared);
+                               ASSERT(last_read != VALUE_NONE);
+
+                               equality = (write_val == last_read);
+                               if (equality != expression->value)
+                                       satisfy_predicate = false;
+                               break;
+                       case NULLITY:
+                               // TODO: implement likely to be null
+                               equality = ((void*) (write_val & 0xffffffff) == NULL);
+                               if (equality != expression->value)
+                                       satisfy_predicate = false;
+                               break;
+                       default:
+                               model_print("unknown predicate token\n");
+                               break;
                        }
 
                        if (!satisfy_predicate)
                                break;
                }
+               delete pred_expr_it;
+
+               if (no_predicate)
+                       return false;
 
                if (!satisfy_predicate) {
                        ASSERT(rf_set != NULL);
-                       (*rf_set)[index] = rf_set->back();
+                       (*rf_set)[rf_index] = rf_set->back();
                        rf_set->pop_back();
                        pruned_writes->push_back(write_act);
                        pruned = true;
                } else
-                       index++;
+                       rf_index++;
        }
 
        return pruned;
 }
+
+/* @brief Put a thread to sleep because no writes in rf_set satisfies the selected predicate.
+ *
+ * @param thread A thread whose last action is a read
+ */
+void NewFuzzer::conditional_sleep(Thread * thread)
+{
+/*
+        int index = paused_thread_list.size();
+
+        model->getScheduler()->add_sleep(thread);
+        paused_thread_list.push_back(thread);
+        paused_thread_table.put(thread, index);        // Update table
+
+        // Add the waiting condition to ModelHistory
+        ModelAction * read = thread->get_pending();
+        thread_id_t tid = thread->get_id();
+        FuncNode * func_node = history->get_curr_func_node(tid);
+   //  inst_act_map_t * inst_act_map = func_node->get_inst_act_map(tid);
+
+        Predicate * selected_branch = get_selected_child_branch(tid);
+   //  ConcretePredicate * concrete = selected_branch->evaluate(inst_act_map, tid);
+        concrete->set_location(read->get_location());
+
+        ASSERT(false);
+
+   //  history->add_waiting_write(concrete);
+        // history->add_waiting_thread is already called in find_threads
+ */
+}
+
+bool NewFuzzer::has_paused_threads()
+{
+       return paused_thread_list.size() != 0;
+}
+
+Thread * NewFuzzer::selectThread(int * threadlist, int numthreads)
+{
+       if (numthreads == 0 && has_paused_threads()) {
+               wake_up_paused_threads(threadlist, &numthreads);
+               //model_print("list size: %d, active t id: %d\n", numthreads, threadlist[0]);
+       }
+       int random_index = random() % numthreads;
+       int thread = threadlist[random_index];
+       thread_id_t curr_tid = int_to_id(thread);
+       return execution->get_thread(curr_tid);
+}
+
+/* Force waking up one of threads paused by Fuzzer, because otherwise
+ * the Fuzzer is not making progress
+ */
+void NewFuzzer::wake_up_paused_threads(int * threadlist, int * numthreads)
+{
+       int random_index = random() % paused_thread_list.size();
+       Thread * thread = paused_thread_list[random_index];
+       model->getScheduler()->remove_sleep(thread);
+
+       Thread * last_thread = paused_thread_list.back();
+       paused_thread_list[random_index] = last_thread;
+       paused_thread_list.pop_back();
+       paused_thread_table.put(last_thread, random_index);     // Update table
+       paused_thread_table.remove(thread);
+
+       thread_id_t tid = thread->get_id();
+       history->remove_waiting_write(tid);
+       history->remove_waiting_thread(tid);
+
+       threadlist[*numthreads] = tid;
+       (*numthreads)++;
+
+/*--
+        Predicate * selected_branch = get_selected_child_branch(tid);
+        update_predicate_score(selected_branch, SLEEP_FAIL_TYPE3);
+ */
+
+       model_print("thread %d is woken up\n", tid);
+}
+
+/* Wake up conditional sleeping threads if the desired write is available */
+void NewFuzzer::notify_paused_thread(Thread * thread)
+{
+       ASSERT(paused_thread_table.contains(thread));
+
+       int index = paused_thread_table.get(thread);
+       model->getScheduler()->remove_sleep(thread);
+
+       Thread * last_thread = paused_thread_list.back();
+       paused_thread_list[index] = last_thread;
+       paused_thread_list.pop_back();
+       paused_thread_table.put(last_thread, index);    // Update table
+       paused_thread_table.remove(thread);
+
+       thread_id_t tid = thread->get_id();
+       history->remove_waiting_write(tid);
+       history->remove_waiting_thread(tid);
+
+/*--
+        Predicate * selected_branch = get_selected_child_branch(tid);
+        update_predicate_score(selected_branch, SLEEP_SUCCESS);
+ */
+
+       model_print("** thread %d is woken up\n", tid);
+}
+
+/* Find threads that may write values that the pending read action is waiting for.
+ * Side effect: waiting thread related info are stored in dist_info_vec
+ *
+ * @return True if any thread is found
+ */
+bool NewFuzzer::find_threads(ModelAction * pending_read)
+{
+       ASSERT(pending_read->is_read());
+
+       void * location = pending_read->get_location();
+       thread_id_t self_id = pending_read->get_tid();
+       bool finds_waiting_for = false;
+
+       SnapVector<FuncNode *> * func_node_list = history->getWrFuncNodes(location);
+       for (uint i = 0;i < func_node_list->size();i++) {
+               FuncNode * target_node = (*func_node_list)[i];
+               for (uint i = 1;i < execution->get_num_threads();i++) {
+                       thread_id_t tid = int_to_id(i);
+                       if (tid == self_id)
+                               continue;
+
+                       FuncNode * node = history->get_curr_func_node(tid);
+                       /* It is possible that thread tid is not in any FuncNode */
+                       if (node == NULL)
+                               continue;
+
+                       int distance = node->compute_distance(target_node);
+                       if (distance != -1) {
+                               finds_waiting_for = true;
+                               //model_print("thread: %d; distance from node %d to node %d: %d\n", tid, node->get_func_id(), target_node->get_func_id(), distance);
+
+                               dist_info_vec.push_back(node_dist_info(tid, target_node, distance));
+                       }
+               }
+       }
+
+       return finds_waiting_for;
+}
+
+bool NewFuzzer::shouldWait(const ModelAction * act)
+{
+       return true;
+}