+
+ 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
+ * @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) {
+ history->add_waiting_thread(self_id, tid, target_node, distance);
+ 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);
+ }
+ }
+ }
+
+ return finds_waiting_for;
+}
+
+/* Update predicate counts and scores (asynchronous) when the read value is not available
+ *
+ * @param type
+ * type 1: find_threads return false
+ * type 2: find_threads return true, but the fuzzer decides that that thread shall not sleep based on sleep score
+ * type 3: threads are put to sleep but woken up before the waited value appears
+ * type 4: threads are put to sleep and the waited vaule appears (success)
+ */
+void NewFuzzer::update_predicate_score(Predicate * predicate, sleep_result_t type)
+{
+ switch (type) {
+ case SLEEP_FAIL_TYPE1:
+ predicate->incr_fail_count();
+
+ /* Do not choose this predicate when reselecting a new branch */
+ failed_predicates.put(predicate, true);
+ break;
+ case SLEEP_FAIL_TYPE2:
+ predicate->incr_fail_count();
+ predicate->decr_sleep_score(1);
+ failed_predicates.put(predicate, true);
+ break;
+ case SLEEP_FAIL_TYPE3:
+ predicate->incr_fail_count();
+ predicate->incr_sleep_score(10);
+ break;
+ case SLEEP_SUCCESS:
+ predicate->decr_sleep_score(10);
+ break;
+ default:
+ model_print("unknown predicate result type.\n");
+ break;
+ }