#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_selected_child_branch()
+ thrd_last_func_inst(),
+ available_branches_tmp_storage(),
+ thrd_selected_child_branch(),
+ 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)
{
- int random_index = random() % rf_set->size();
+// 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]) {
+ 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);
+
+ 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;
+ }
- SnapVector<func_id_list_t> * thrd_func_list = execution->get_thrd_func_list();
- uint32_t func_id = (*thrd_func_list)[thread_id].back();
+ // 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);
- FuncNode * func_node = history->get_func_node(func_id);
- FuncInst * read_inst = func_node->get_inst(read);
- Predicate * curr_pred = func_node->get_predicate_tree_position(tid);
- selectBranch(thread_id, curr_pred, read_inst);
+ // 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++) {
+ 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);
}
- Predicate * selected_branch = thrd_selected_child_branch[thread_id];
- if (selected_branch == NULL)
- return random_index;
+ int random_index = random() % rf_set->size();
+
+ return random_index;
+}
- FuncInst * read_inst = selected_branch->get_func_inst();
- PredExprSet * pred_expressions = selected_branch->get_pred_expressions();
+/* 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();
- model_print("thread %d ", tid);
- read_inst->print();
+ ASSERT(!rf_set->empty());
+ if (curr_pred == NULL || read_inst == NULL)
+ return false;
- // unset predicates
- if (pred_expressions->getSize() == 0)
- return random_index;
-/*
- PredExprSetIter * pred_expr_it = pred_expressions->iterator();
- while (pred_expr_it->hasNext()) {
- struct pred_expr * expression = pred_expr_it->next();
+ 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)
+{
+ int thread_id = id_to_int(tid);
+ if ( thrd_selected_child_branch.size() <= (uint) thread_id)
+ thrd_selected_child_branch.resize(thread_id + 1);
+
+ if (curr_pred == NULL || read_inst == NULL) {
+ thrd_selected_child_branch[thread_id] = NULL;
+ return NULL;
+ }
+
+ // predicate children have not been generated
+ if (available_branches_tmp_storage.size() == 0) {
+ thrd_selected_child_branch[thread_id] = NULL;
+ return NULL;
+ }
+
+ int index = choose_branch_index(&available_branches_tmp_storage);
+ Predicate * selected_branch = available_branches_tmp_storage[ index ];
+
+ /* 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)
+{
+ int thread_id = id_to_int(tid);
+ if (thrd_selected_child_branch.size() <= (uint) thread_id)
+ return NULL;
- switch(expression->token) {
+ return thrd_selected_child_branch[thread_id];
+}
+
+/* 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)
+{
+ if (pred == NULL)
+ return false;
+
+ PredExprSet * pred_expressions = pred->get_pred_expressions();
+ if (pred_expressions->getSize() == 0) // unset predicates
+ return false;
+
+ int thread_id = id_to_int(tid);
+ uint old_size = thrd_pruned_writes.size();
+ 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++)
+ 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 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();
+ bool equality;
+
+ switch (expression->token) {
case NOPREDICATE:
- read_inst->print();
- read->print();
- model_print("no predicate\n");
- return random_index;
+ no_predicate = true;
+ break;
case EQUALITY:
- model_print("equality predicate, under construction\n");
+ 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:
- model_print("nullity predicate, under construction\n");
+ // 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)[rf_index] = rf_set->back();
+ rf_set->pop_back();
+ pruned_writes->push_back(write_act);
+ pruned = true;
+ } else
+ 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
*/
- return random_index;
}
-void NewFuzzer::selectBranch(int thread_id, Predicate * curr_pred, FuncInst * read_inst)
+bool NewFuzzer::has_paused_threads()
{
- if ( thrd_selected_child_branch.size() <= (uint) thread_id)
- thrd_selected_child_branch.resize(thread_id + 1);
+ return paused_thread_list.size() != 0;
+}
- if (read_inst == NULL) {
- thrd_selected_child_branch[thread_id] = NULL;
- return;
+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]);
}
- ModelVector<Predicate *> * children = curr_pred->get_children();
- SnapVector<Predicate *> branches;
+ 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);
+}
- for (uint i = 0; i < children->size(); i++) {
- Predicate * child = (*children)[i];
- if (child->get_func_inst() == read_inst)
- branches.push_back(child);
- }
+/* 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);
- // predicate children have not been generated
- if (branches.size() == 0) {
- thrd_selected_child_branch[thread_id] = NULL;
- return;
+ 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));
+ }
+ }
}
- // randomly select a branch
- int random_index = random() % branches.size();
- Predicate * random_branch = branches[ random_index ];
- thrd_selected_child_branch[thread_id] = random_branch;
+ return finds_waiting_for;
+}
+
+bool NewFuzzer::shouldWait(const ModelAction * act)
+{
+ return random() & 1;
}