Add some methods for WaitObj
[c11tester.git] / newfuzzer.cc
index df3f2ca6c9ea6eaf62858667e2898dec53e14635..69f1ce148bb3c2eb70f2252c1f8cba07b7722888 100644 (file)
@@ -1,14 +1,24 @@
 #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 "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_selected_child_branch(),
+       thrd_pruned_writes(),
+       paused_thread_set(),
+       paused_thread_table(128)
 {}
 
 /**
@@ -22,7 +32,7 @@ void NewFuzzer::register_engine(ModelHistory * history, ModelExecution *executio
 
 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);
@@ -34,62 +44,56 @@ int NewFuzzer::selectWrite(ModelAction *read, SnapVector<ModelAction *> * rf_set
        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);
-               FuncInst * read_inst = func_node->get_inst(read);
+               FuncNode * func_node = history->get_curr_func_node(tid);
                Predicate * curr_pred = func_node->get_predicate_tree_position(tid);
-               selectBranch(thread_id, curr_pred, read_inst);
+               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);
        }
 
-       Predicate * selected_branch = thrd_selected_child_branch[thread_id];
-       if (selected_branch == NULL)
-               return random_index;
+       // 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();
 
-       FuncInst * read_inst = selected_branch->get_func_inst();
-       PredExprSet * pred_expressions = selected_branch->get_pred_expressions();
+               conditional_sleep(read_thread);
 
-       model_print("thread %d ", tid);
-       read_inst->print();
+               find_threads(read);
 
-       // unset predicates
-       if (pred_expressions->getSize() == 0)
-               return random_index;
+               return -1;
 /*
-       PredExprSetIter * pred_expr_it = pred_expressions->iterator();
-       while (pred_expr_it->hasNext()) {
-               struct pred_expr * expression = pred_expr_it->next();
-
-               switch(expression->token) {
-                       case NOPREDICATE:
-                               read_inst->print();
-                               read->print();
-                               model_print("no predicate\n");
-                               return random_index;
-                       case EQUALITY:
-                               model_print("equality predicate, under construction\n");
-                               break;
-                       case NULLITY:
-                               model_print("nullity predicate, under construction\n");
-                               break;
-                       default:
-                               model_print("unknown predicate token\n");
-                               break;
-               }
-       }
+               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;
 }
 
-void NewFuzzer::selectBranch(int thread_id, Predicate * curr_pred, FuncInst * read_inst)
+/* 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 (read_inst == NULL) {
+       if (curr_pred == NULL || read_inst == NULL) {
                thrd_selected_child_branch[thread_id] = NULL;
-               return;
+               return NULL;
        }
 
        ModelVector<Predicate *> * children = curr_pred->get_children();
@@ -104,11 +108,219 @@ void NewFuzzer::selectBranch(int thread_id, Predicate * curr_pred, FuncInst * re
        // predicate children have not been generated
        if (branches.size() == 0) {
                thrd_selected_child_branch[thread_id] = NULL;
-               return;
+               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];
+               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, distance);
+                               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;
 }