#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 "predicate.h"
+#include "concretepredicate.h"
+
+#include "model.h"
+#include "schedule.h"
+#include "execution.h"
+
+NewFuzzer::NewFuzzer() :
+ thrd_last_read_act(),
+ thrd_curr_pred(),
+ thrd_selected_child_branch(),
+ thrd_pruned_writes(),
+ paused_thread_set(),
+ paused_thread_table(128)
+{}
/**
* @brief Register the ModelHistory and ModelExecution engine
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);
- SnapVector<func_id_list_t> * thrd_func_list = execution->get_thrd_func_list();
- uint32_t func_id = (*thrd_func_list)[thread_id].back();
+ if (thrd_last_read_act.size() <= (uint) thread_id)
+ thrd_last_read_act.resize(thread_id + 1);
- 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);
+ // 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;
- ModelVector<Predicate *> * children = curr_pred->get_children();
- if (children->size() == 0)
- return random() % rf_set->size();
+ 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);
+
+ inst_act_map_t * inst_act_map = func_node->get_inst_act_map(tid);
+ prune_writes(tid, selected_branch, rf_set, inst_act_map);
+ }
+
+ // No write satisfies the selected predicate, so pause this thread.
+ if ( rf_set->size() == 0 ) {
+ Thread * read_thread = execution->get_thread(tid);
+ 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());
+ // reset thread pending action and revert sequence numbers
+ read_thread->set_pending(read);
+ read->reset_seq_number();
+ execution->restore_last_seq_num();
+
+ conditional_sleep(read_thread);
+
+ find_threads(read);
+
+ return -1;
+/*
+ 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] );
+ pruned_writes->clear();
+*/
+ }
+
+ 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
+ * @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;
+ }
+
+ 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) {
+ 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;
+
+ return random_branch;
+}
+
+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;
+
+ 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, inst_act_map_t * inst_act_map)
+{
+ 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 index = 0;
+
+ ConcretePredicate * concrete_pred = pred->evaluate(inst_act_map, tid);
+ SnapVector<struct concrete_pred_expr> * concrete_exprs = concrete_pred->getExpressions();
+
+ while ( index < rf_set->size() ) {
+ ModelAction * write_act = (*rf_set)[index];
+ uint64_t write_val = write_act->get_write_value();
+ bool satisfy_predicate = true;
+
+ for (uint i = 0; i < concrete_exprs->size(); i++) {
+ struct concrete_pred_expr concrete = (*concrete_exprs)[i];
+ bool equality;
+
+ switch (concrete.token) {
+ case NOPREDICATE:
+ return false;
+ case EQUALITY:
+ equality = (write_val == concrete.value);
+ if (equality != concrete.equality)
+ satisfy_predicate = false;
+ break;
+ case NULLITY:
+ equality = ((void*)write_val == NULL);
+ if (equality != concrete.equality)
+ satisfy_predicate = false;
+ break;
+ default:
+ model_print("unknown predicate token\n");
+ break;
+ }
+
+ if (!satisfy_predicate)
+ break;
+ }
+
+ if (!satisfy_predicate) {
+ ASSERT(rf_set != NULL);
+ (*rf_set)[index] = rf_set->back();
+ rf_set->pop_back();
+ pruned_writes->push_back(write_act);
+ pruned = true;
+ } else
+ index++;
+ }
+
+ delete concrete_pred;
+
+ 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_set.size();
+
+ model->getScheduler()->add_sleep(thread);
+ paused_thread_set.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());
+
+ history->add_waiting_write(concrete);
+}
+
+bool NewFuzzer::has_paused_threads()
+{
+ return paused_thread_set.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 model->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_set.size();
+ Thread * thread = paused_thread_set[random_index];
+ model->getScheduler()->remove_sleep(thread);
+
+ Thread * last_thread = paused_thread_set.back();
+ paused_thread_set[random_index] = last_thread;
+ paused_thread_set.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);
+
+ model_print("thread %d is woken up\n", tid);
+ threadlist[*numthreads] = tid;
+ (*numthreads)++;
+}
+
+/* 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_set.back();
+ paused_thread_set[index] = last_thread;
+ paused_thread_set.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);
+}
+
+/* Find threads that may write values that the pending read action is waiting for */
+void NewFuzzer::find_threads(ModelAction * pending_read)
+{
+ void * location = pending_read->get_location();
+ thread_id_t self_id = pending_read->get_tid();
+
+ 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];
+ model_print("node %s may write to loc %p\n", target_node->get_func_name(), location);
+
+ 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);
+ if (node == NULL)
+ continue;
+
+ int distance = node->compute_distance(target_node);
+ model_print("thread: %d; distance from node %d to node %d: %d\n", tid, node->get_func_id(), target_node->get_func_id(), distance);
+ }
+ }
+}
+
+bool NewFuzzer::shouldWait(const ModelAction * act)
+{
+ return random() & 1;
+}
projects / c11tester.git / blobdiff