Fix bug that prevents graph generation from compiling.
[model-checker.git] / execution.cc
index 41fdfc77b6b07bf9eb2754f230f11560225962bb..f2c50c4321c67cd83da4c905ac1bcd652307b4a0 100644 (file)
@@ -58,17 +58,17 @@ struct model_snapshot_members {
 
 /** @brief Constructor */
 ModelExecution::ModelExecution(ModelChecker *m,
-               struct model_params *params,
+               const struct model_params *params,
                Scheduler *scheduler,
                NodeStack *node_stack) :
        model(m),
        params(params),
        scheduler(scheduler),
-       action_trace(new action_list_t()),
-       thread_map(new HashTable<int, Thread *, int>()),
-       obj_map(new HashTable<const void *, action_list_t *, uintptr_t, 4>()),
-       condvar_waiters_map(new HashTable<const void *, action_list_t *, uintptr_t, 4>()),
-       obj_thrd_map(new HashTable<void *, SnapVector<action_list_t> *, uintptr_t, 4 >()),
+       action_trace(),
+       thread_map(2), /* We'll always need at least 2 threads */
+       obj_map(),
+       condvar_waiters_map(),
+       obj_thrd_map(),
        promises(),
        futurevalues(),
        pending_rel_seqs(),
@@ -80,21 +80,16 @@ ModelExecution::ModelExecution(ModelChecker *m,
 {
        /* Initialize a model-checker thread, for special ModelActions */
        model_thread = new Thread(get_next_id());
-       thread_map->put(id_to_int(model_thread->get_id()), model_thread);
+       add_thread(model_thread);
        scheduler->register_engine(this);
+       node_stack->register_engine(this);
 }
 
 /** @brief Destructor */
 ModelExecution::~ModelExecution()
 {
        for (unsigned int i = 0; i < get_num_threads(); i++)
-               delete thread_map->get(i);
-       delete thread_map;
-
-       delete obj_thrd_map;
-       delete obj_map;
-       delete condvar_waiters_map;
-       delete action_trace;
+               delete get_thread(int_to_id(i));
 
        for (unsigned int i = 0; i < promises.size(); i++)
                delete promises[i];
@@ -130,7 +125,7 @@ static SnapVector<action_list_t> * get_safe_ptr_vect_action(HashTable<void *, Sn
 
 action_list_t * ModelExecution::get_actions_on_obj(void * obj, thread_id_t tid) const
 {
-       SnapVector<action_list_t> *wrv=obj_thrd_map->get(obj);
+       SnapVector<action_list_t> *wrv = obj_thrd_map.get(obj);
        if (wrv==NULL)
                return NULL;
        unsigned int thread=id_to_int(tid);
@@ -269,6 +264,28 @@ bool ModelExecution::is_deadlocked() const
        return blocking_threads;
 }
 
+/**
+ * @brief Check if we are yield-blocked
+ *
+ * A program can be "yield-blocked" if all threads are ready to execute a
+ * yield.
+ *
+ * @return True if the program is yield-blocked; false otherwise
+ */
+bool ModelExecution::is_yieldblocked() const
+{
+       if (!params->yieldblock)
+               return false;
+
+       for (unsigned int i = 0; i < get_num_threads(); i++) {
+               thread_id_t tid = int_to_id(i);
+               Thread *t = get_thread(tid);
+               if (t->get_pending() && t->get_pending()->is_yield())
+                       return true;
+       }
+       return false;
+}
+
 /**
  * Check if this is a complete execution. That is, have all thread completed
  * execution (rather than exiting because sleep sets have forced a redundant
@@ -278,6 +295,8 @@ bool ModelExecution::is_deadlocked() const
  */
 bool ModelExecution::is_complete_execution() const
 {
+       if (is_yieldblocked())
+               return false;
        for (unsigned int i = 0; i < get_num_threads(); i++)
                if (is_enabled(int_to_id(i)))
                        return false;
@@ -312,8 +331,8 @@ ModelAction * ModelExecution::get_last_fence_conflict(ModelAction *act) const
                return NULL;
 
        /* Skip past the release */
-       action_list_t *list = action_trace;
-       action_list_t::reverse_iterator rit;
+       const action_list_t *list = &action_trace;
+       action_list_t::const_reverse_iterator rit;
        for (rit = list->rbegin(); rit != list->rend(); rit++)
                if (*rit == last_release)
                        break;
@@ -371,17 +390,22 @@ ModelAction * ModelExecution::get_last_fence_conflict(ModelAction *act) const
 ModelAction * ModelExecution::get_last_conflict(ModelAction *act) const
 {
        switch (act->get_type()) {
-       /* case ATOMIC_FENCE: fences don't directly cause backtracking */
+       case ATOMIC_FENCE:
+               /* Only seq-cst fences can (directly) cause backtracking */
+               if (!act->is_seqcst())
+                       break;
        case ATOMIC_READ:
        case ATOMIC_WRITE:
        case ATOMIC_RMW: {
                ModelAction *ret = NULL;
 
                /* linear search: from most recent to oldest */
-               action_list_t *list = get_safe_ptr_action(obj_map, act->get_location());
+               action_list_t *list = obj_map.get(act->get_location());
                action_list_t::reverse_iterator rit;
                for (rit = list->rbegin(); rit != list->rend(); rit++) {
                        ModelAction *prev = *rit;
+                       if (prev == act)
+                               continue;
                        if (prev->could_synchronize_with(act)) {
                                ret = prev;
                                break;
@@ -400,7 +424,7 @@ ModelAction * ModelExecution::get_last_conflict(ModelAction *act) const
        case ATOMIC_LOCK:
        case ATOMIC_TRYLOCK: {
                /* linear search: from most recent to oldest */
-               action_list_t *list = get_safe_ptr_action(obj_map, act->get_location());
+               action_list_t *list = obj_map.get(act->get_location());
                action_list_t::reverse_iterator rit;
                for (rit = list->rbegin(); rit != list->rend(); rit++) {
                        ModelAction *prev = *rit;
@@ -411,7 +435,7 @@ ModelAction * ModelExecution::get_last_conflict(ModelAction *act) const
        }
        case ATOMIC_UNLOCK: {
                /* linear search: from most recent to oldest */
-               action_list_t *list = get_safe_ptr_action(obj_map, act->get_location());
+               action_list_t *list = obj_map.get(act->get_location());
                action_list_t::reverse_iterator rit;
                for (rit = list->rbegin(); rit != list->rend(); rit++) {
                        ModelAction *prev = *rit;
@@ -422,7 +446,7 @@ ModelAction * ModelExecution::get_last_conflict(ModelAction *act) const
        }
        case ATOMIC_WAIT: {
                /* linear search: from most recent to oldest */
-               action_list_t *list = get_safe_ptr_action(obj_map, act->get_location());
+               action_list_t *list = obj_map.get(act->get_location());
                action_list_t::reverse_iterator rit;
                for (rit = list->rbegin(); rit != list->rend(); rit++) {
                        ModelAction *prev = *rit;
@@ -437,7 +461,7 @@ ModelAction * ModelExecution::get_last_conflict(ModelAction *act) const
        case ATOMIC_NOTIFY_ALL:
        case ATOMIC_NOTIFY_ONE: {
                /* linear search: from most recent to oldest */
-               action_list_t *list = get_safe_ptr_action(obj_map, act->get_location());
+               action_list_t *list = obj_map.get(act->get_location());
                action_list_t::reverse_iterator rit;
                for (rit = list->rbegin(); rit != list->rend(); rit++) {
                        ModelAction *prev = *rit;
@@ -697,14 +721,14 @@ bool ModelExecution::process_mutex(ModelAction *curr)
 
                /* Should we go to sleep? (simulate spurious failures) */
                if (curr->get_node()->get_misc() == 0) {
-                       get_safe_ptr_action(condvar_waiters_map, curr->get_location())->push_back(curr);
+                       get_safe_ptr_action(&condvar_waiters_map, curr->get_location())->push_back(curr);
                        /* disable us */
                        scheduler->sleep(get_thread(curr));
                }
                break;
        }
        case ATOMIC_NOTIFY_ALL: {
-               action_list_t *waiters = get_safe_ptr_action(condvar_waiters_map, curr->get_location());
+               action_list_t *waiters = get_safe_ptr_action(&condvar_waiters_map, curr->get_location());
                //activate all the waiting threads
                for (action_list_t::iterator rit = waiters->begin(); rit != waiters->end(); rit++) {
                        scheduler->wake(get_thread(*rit));
@@ -713,7 +737,7 @@ bool ModelExecution::process_mutex(ModelAction *curr)
                break;
        }
        case ATOMIC_NOTIFY_ONE: {
-               action_list_t *waiters = get_safe_ptr_action(condvar_waiters_map, curr->get_location());
+               action_list_t *waiters = get_safe_ptr_action(&condvar_waiters_map, curr->get_location());
                int wakeupthread = curr->get_node()->get_misc();
                action_list_t::iterator it = waiters->begin();
                advance(it, wakeupthread);
@@ -859,7 +883,7 @@ bool ModelExecution::process_fence(ModelAction *curr)
         */
        bool updated = false;
        if (curr->is_acquire()) {
-               action_list_t *list = action_trace;
+               action_list_t *list = &action_trace;
                action_list_t::reverse_iterator rit;
                /* Find X : is_read(X) && X --sb-> curr */
                for (rit = list->rbegin(); rit != list->rend(); rit++) {
@@ -1007,7 +1031,7 @@ void ModelExecution::process_relseq_fixup(ModelAction *curr, work_queue_t *work_
                work_queue->push_back(MOEdgeWorkEntry(acquire));
 
                /* propagate synchronization to later actions */
-               action_list_t::reverse_iterator rit = action_trace->rbegin();
+               action_list_t::reverse_iterator rit = action_trace.rbegin();
                for (; (*rit) != acquire; rit++) {
                        ModelAction *propagate = *rit;
                        if (acquire->happens_before(propagate)) {
@@ -1092,7 +1116,7 @@ bool ModelExecution::initialize_curr_action(ModelAction **curr)
                else if (newcurr->is_wait())
                        newcurr->get_node()->set_misc_max(2);
                else if (newcurr->is_notify_one()) {
-                       newcurr->get_node()->set_misc_max(get_safe_ptr_action(condvar_waiters_map, newcurr->get_location())->size());
+                       newcurr->get_node()->set_misc_max(get_safe_ptr_action(&condvar_waiters_map, newcurr->get_location())->size());
                }
                return true; /* This was a new ModelAction */
        }
@@ -1181,9 +1205,10 @@ void ModelExecution::thread_blocking_check_promises(Thread *blocker, Thread *wai
 /**
  * @brief Check whether a model action is enabled.
  *
- * Checks whether a lock or join operation would be successful (i.e., is the
- * lock already locked, or is the joined thread already complete). If not, put
- * the action in a waiter list.
+ * Checks whether an operation would be successful (i.e., is a lock already
+ * locked, or is the joined thread already complete).
+ *
+ * For yield-blocking, yields are never enabled.
  *
  * @param curr is the ModelAction to check whether it is enabled.
  * @return a bool that indicates whether the action is enabled.
@@ -1200,6 +1225,8 @@ bool ModelExecution::check_action_enabled(ModelAction *curr) {
                        thread_blocking_check_promises(blocking, get_thread(curr));
                        return false;
                }
+       } else if (params->yieldblock && curr->is_yield()) {
+               return false;
        }
 
        return true;
@@ -1214,7 +1241,7 @@ bool ModelExecution::check_action_enabled(ModelAction *curr) {
  *
  * @param curr The current action to process
  * @return The ModelAction that is actually executed; may be different than
- * curr; may be NULL, if the current action is not enabled to run
+ * curr
  */
 ModelAction * ModelExecution::check_current_action(ModelAction *curr)
 {
@@ -1437,7 +1464,7 @@ bool ModelExecution::should_read_instead(const ModelAction *curr, const T *rf, c
        if (!mo_graph->checkReachable(rf, other_rf))
                return false;
 
-       SnapVector<action_list_t> *thrd_lists = get_safe_ptr_vect_action(obj_thrd_map, curr->get_location());
+       SnapVector<action_list_t> *thrd_lists = obj_thrd_map.get(curr->get_location());
        action_list_t *list = &(*thrd_lists)[id_to_int(curr->get_tid())];
        action_list_t::reverse_iterator rit = list->rbegin();
        ASSERT((*rit) == curr);
@@ -1480,7 +1507,7 @@ bool ModelExecution::check_recency(ModelAction *curr, const T *rf) const
                        curr->get_node()->get_read_from_promise_size() <= 1)
                return true;
 
-       SnapVector<action_list_t> *thrd_lists = get_safe_ptr_vect_action(obj_thrd_map, curr->get_location());
+       SnapVector<action_list_t> *thrd_lists = obj_thrd_map.get(curr->get_location());
        int tid = id_to_int(curr->get_tid());
        ASSERT(tid < (int)thrd_lists->size());
        action_list_t *list = &(*thrd_lists)[tid];
@@ -1537,7 +1564,7 @@ bool ModelExecution::check_recency(ModelAction *curr, const T *rf) const
 template <typename rf_type>
 bool ModelExecution::r_modification_order(ModelAction *curr, const rf_type *rf)
 {
-       SnapVector<action_list_t> *thrd_lists = get_safe_ptr_vect_action(obj_thrd_map, curr->get_location());
+       SnapVector<action_list_t> *thrd_lists = obj_thrd_map.get(curr->get_location());
        unsigned int i;
        bool added = false;
        ASSERT(curr->is_read());
@@ -1663,7 +1690,7 @@ bool ModelExecution::r_modification_order(ModelAction *curr, const rf_type *rf)
  */
 bool ModelExecution::w_modification_order(ModelAction *curr, ModelVector<ModelAction *> *send_fv)
 {
-       SnapVector<action_list_t> *thrd_lists = get_safe_ptr_vect_action(obj_thrd_map, curr->get_location());
+       SnapVector<action_list_t> *thrd_lists = obj_thrd_map.get(curr->get_location());
        unsigned int i;
        bool added = false;
        ASSERT(curr->is_write());
@@ -1807,7 +1834,7 @@ bool ModelExecution::thin_air_constraint_may_allow(const ModelAction *writer, co
  */
 bool ModelExecution::mo_may_allow(const ModelAction *writer, const ModelAction *reader)
 {
-       SnapVector<action_list_t> *thrd_lists = get_safe_ptr_vect_action(obj_thrd_map, reader->get_location());
+       SnapVector<action_list_t> *thrd_lists = obj_thrd_map.get(reader->get_location());
        unsigned int i;
        /* Iterate over all threads */
        for (i = 0; i < thrd_lists->size(); i++) {
@@ -1908,7 +1935,7 @@ bool ModelExecution::release_seq_heads(const ModelAction *rf,
                release_heads->push_back(fence_release);
 
        int tid = id_to_int(rf->get_tid());
-       SnapVector<action_list_t> *thrd_lists = get_safe_ptr_vect_action(obj_thrd_map, rf->get_location());
+       SnapVector<action_list_t> *thrd_lists = obj_thrd_map.get(rf->get_location());
        action_list_t *list = &(*thrd_lists)[tid];
        action_list_t::const_reverse_iterator rit;
 
@@ -2080,7 +2107,7 @@ bool ModelExecution::resolve_release_sequences(void *location, work_queue_t *wor
                                work_queue->push_back(MOEdgeWorkEntry(acquire));
 
                        /* propagate synchronization to later actions */
-                       action_list_t::reverse_iterator rit = action_trace->rbegin();
+                       action_list_t::reverse_iterator rit = action_trace.rbegin();
                        for (; (*rit) != acquire; rit++) {
                                ModelAction *propagate = *rit;
                                if (acquire->happens_before(propagate)) {
@@ -2116,7 +2143,7 @@ void ModelExecution::add_action_to_lists(ModelAction *act)
        int tid = id_to_int(act->get_tid());
        ModelAction *uninit = NULL;
        int uninit_id = -1;
-       action_list_t *list = get_safe_ptr_action(obj_map, act->get_location());
+       action_list_t *list = get_safe_ptr_action(&obj_map, act->get_location());
        if (list->empty() && act->is_atomic_var()) {
                uninit = get_uninitialized_action(act);
                uninit_id = id_to_int(uninit->get_tid());
@@ -2124,11 +2151,11 @@ void ModelExecution::add_action_to_lists(ModelAction *act)
        }
        list->push_back(act);
 
-       action_trace->push_back(act);
+       action_trace.push_back(act);
        if (uninit)
-               action_trace->push_front(uninit);
+               action_trace.push_front(uninit);
 
-       SnapVector<action_list_t> *vec = get_safe_ptr_vect_action(obj_thrd_map, act->get_location());
+       SnapVector<action_list_t> *vec = get_safe_ptr_vect_action(&obj_thrd_map, act->get_location());
        if (tid >= (int)vec->size())
                vec->resize(priv->next_thread_id);
        (*vec)[tid].push_back(act);
@@ -2149,9 +2176,9 @@ void ModelExecution::add_action_to_lists(ModelAction *act)
 
        if (act->is_wait()) {
                void *mutex_loc = (void *) act->get_value();
-               get_safe_ptr_action(obj_map, mutex_loc)->push_back(act);
+               get_safe_ptr_action(&obj_map, mutex_loc)->push_back(act);
 
-               SnapVector<action_list_t> *vec = get_safe_ptr_vect_action(obj_thrd_map, mutex_loc);
+               SnapVector<action_list_t> *vec = get_safe_ptr_vect_action(&obj_thrd_map, mutex_loc);
                if (tid >= (int)vec->size())
                        vec->resize(priv->next_thread_id);
                (*vec)[tid].push_back(act);
@@ -2197,7 +2224,7 @@ ModelAction * ModelExecution::get_last_fence_release(thread_id_t tid) const
 ModelAction * ModelExecution::get_last_seq_cst_write(ModelAction *curr) const
 {
        void *location = curr->get_location();
-       action_list_t *list = get_safe_ptr_action(obj_map, location);
+       action_list_t *list = obj_map.get(location);
        /* Find: max({i in dom(S) | seq_cst(t_i) && isWrite(t_i) && samevar(t_i, t)}) */
        action_list_t::reverse_iterator rit;
        for (rit = list->rbegin(); (*rit) != curr; rit++)
@@ -2219,8 +2246,12 @@ ModelAction * ModelExecution::get_last_seq_cst_write(ModelAction *curr) const
  */
 ModelAction * ModelExecution::get_last_seq_cst_fence(thread_id_t tid, const ModelAction *before_fence) const
 {
-       /* All fences should have NULL location */
-       action_list_t *list = get_safe_ptr_action(obj_map, NULL);
+       /* All fences should have location FENCE_LOCATION */
+       action_list_t *list = obj_map.get(FENCE_LOCATION);
+
+       if (!list)
+               return NULL;
+
        action_list_t::reverse_iterator rit = list->rbegin();
 
        if (before_fence) {
@@ -2249,7 +2280,7 @@ ModelAction * ModelExecution::get_last_seq_cst_fence(thread_id_t tid, const Mode
 ModelAction * ModelExecution::get_last_unlock(ModelAction *curr) const
 {
        void *location = curr->get_location();
-       action_list_t *list = get_safe_ptr_action(obj_map, location);
+       action_list_t *list = obj_map.get(location);
        /* Find: max({i in dom(S) | isUnlock(t_i) && samevar(t_i, t)}) */
        action_list_t::reverse_iterator rit;
        for (rit = list->rbegin(); rit != list->rend(); rit++)
@@ -2474,7 +2505,7 @@ void ModelExecution::compute_relseq_breakwrites(ModelAction *curr)
  */
 void ModelExecution::build_may_read_from(ModelAction *curr)
 {
-       SnapVector<action_list_t> *thrd_lists = get_safe_ptr_vect_action(obj_thrd_map, curr->get_location());
+       SnapVector<action_list_t> *thrd_lists = obj_thrd_map.get(curr->get_location());
        unsigned int i;
        ASSERT(curr->is_read());
 
@@ -2584,9 +2615,9 @@ ModelAction * ModelExecution::get_uninitialized_action(const ModelAction *curr)
        return act;
 }
 
-static void print_list(action_list_t *list)
+static void print_list(const action_list_t *list)
 {
-       action_list_t::iterator it;
+       action_list_t::const_iterator it;
 
        model_print("---------------------------------------------------------------------\n");
 
@@ -2612,7 +2643,7 @@ void ModelExecution::dumpGraph(char *filename) const
        mo_graph->dumpNodes(file);
        ModelAction **thread_array = (ModelAction **)model_calloc(1, sizeof(ModelAction *) * get_num_threads());
 
-       for (action_list_t::iterator it = action_trace->begin(); it != action_trace->end(); it++) {
+       for (action_list_t::const_iterator it = action_trace.begin(); it != action_trace.end(); it++) {
                ModelAction *act = *it;
                if (act->is_read()) {
                        mo_graph->dot_print_node(file, act);
@@ -2655,12 +2686,14 @@ void ModelExecution::print_summary() const
 
        model_print("Execution %d:", get_execution_number());
        if (isfeasibleprefix()) {
+               if (is_yieldblocked())
+                       model_print(" YIELD BLOCKED");
                if (scheduler->all_threads_sleeping())
                        model_print(" SLEEP-SET REDUNDANT");
                model_print("\n");
        } else
                print_infeasibility(" INFEASIBLE");
-       print_list(action_trace);
+       print_list(&action_trace);
        model_print("\n");
        if (!promises.empty()) {
                model_print("Pending promises:\n");
@@ -2679,7 +2712,10 @@ void ModelExecution::print_summary() const
  */
 void ModelExecution::add_thread(Thread *t)
 {
-       thread_map->put(id_to_int(t->get_id()), t);
+       unsigned int i = id_to_int(t->get_id());
+       if (i >= thread_map.size())
+               thread_map.resize(i + 1);
+       thread_map[i] = t;
        if (!t->is_model_thread())
                scheduler->add_thread(t);
 }
@@ -2691,7 +2727,10 @@ void ModelExecution::add_thread(Thread *t)
  */
 Thread * ModelExecution::get_thread(thread_id_t tid) const
 {
-       return thread_map->get(id_to_int(tid));
+       unsigned int i = id_to_int(tid);
+       if (i < thread_map.size())
+               return thread_map[i];
+       return NULL;
 }
 
 /**
@@ -2806,7 +2845,7 @@ void ModelExecution::fixup_release_sequences()
 {
        while (!pending_rel_seqs.empty() &&
                        is_feasible_prefix_ignore_relseq() &&
-                       !unrealizedraces.empty()) {
+                       haveUnrealizedRaces()) {
                model_print("*** WARNING: release sequence fixup action "
                                "(%zu pending release seuqence(s)) ***\n",
                                pending_rel_seqs.size());