Merge branch 'norris'
[c11tester.git] / model.cc
index 98c6e645382bf2bdc32bc75e45e3a90b1de4a3cd..25f85d0ee4403ebb1b6ef00531cf872bbdd29892 100644 (file)
--- a/model.cc
+++ b/model.cc
 ModelChecker *model;
 
 /** @brief Constructor */
-ModelChecker::ModelChecker() :
+ModelChecker::ModelChecker(struct model_params params) :
        /* Initialize default scheduler */
        scheduler(new Scheduler()),
        /* First thread created will have id INITIAL_THREAD_ID */
        next_thread_id(INITIAL_THREAD_ID),
        used_sequence_numbers(0),
        num_executions(0),
+       params(params),
        current_action(NULL),
        diverge(NULL),
        nextThread(THREAD_ID_T_NONE),
@@ -199,7 +200,7 @@ ModelAction * ModelChecker::get_last_conflict(ModelAction *act)
                        return NULL;
        }
        /* linear search: from most recent to oldest */
-       action_list_t *list = obj_map->ensureptr(act->get_location());
+       action_list_t *list = obj_map->get_safe_ptr(act->get_location());
        action_list_t::reverse_iterator rit;
        for (rit = list->rbegin(); rit != list->rend(); rit++) {
                ModelAction *prev = *rit;
@@ -265,11 +266,11 @@ void ModelChecker::check_current_action(void)
                return;
        }
 
-       if (curr->is_rmwc()||curr->is_rmw()) {
-               ModelAction *tmp=process_rmw(curr);
+       if (curr->is_rmwc() || curr->is_rmw()) {
+               ModelAction *tmp = process_rmw(curr);
                already_added = true;
                delete curr;
-               curr=tmp;
+               curr = tmp;
        } else {
                ModelAction * tmp = node_stack->explore_action(curr);
                if (tmp) {
@@ -279,9 +280,8 @@ void ModelChecker::check_current_action(void)
                                tmp->copy_typeandorder(curr);
 
                        /* If we have diverged, we need to reset the clock vector. */
-                       if (diverge==NULL) {
+                       if (diverge == NULL)
                                tmp->create_cv(get_parent_action(tmp->get_tid()));
-                       }
 
                        delete curr;
                        curr = tmp;
@@ -306,16 +306,15 @@ void ModelChecker::check_current_action(void)
        }
 
        /* Deal with new thread */
-       if (curr->get_type() == THREAD_START) {
+       if (curr->get_type() == THREAD_START)
                check_promises(NULL, curr->get_cv());
-       }
 
        /* Assign reads_from values */
        Thread *th = get_thread(curr->get_tid());
        uint64_t value = VALUE_NONE;
        if (curr->is_read()) {
                const ModelAction *reads_from = curr->get_node()->get_read_from();
-               if (reads_from!=NULL) {
+               if (reads_from != NULL) {
                        value = reads_from->get_value();
                        /* Assign reads_from, perform release/acquire synchronization */
                        curr->read_from(reads_from);
@@ -324,7 +323,7 @@ void ModelChecker::check_current_action(void)
                        /* Read from future value */
                        value = curr->get_node()->get_future_value();
                        curr->read_from(NULL);
-                       Promise * valuepromise=new Promise(curr, value);
+                       Promise * valuepromise = new Promise(curr, value);
                        promises->push_back(valuepromise);
                }
        } else if (curr->is_write()) {
@@ -338,21 +337,21 @@ void ModelChecker::check_current_action(void)
        if (!already_added)
                add_action_to_lists(curr);
 
-       /* Is there a better interface for setting the next thread rather
+       /** @todo Is there a better interface for setting the next thread rather
                 than this field/convoluted approach?  Perhaps like just returning
                 it or something? */
 
        /* Do not split atomic actions. */
-       if (curr->is_rmwr()) {
+       if (curr->is_rmwr())
                nextThread = thread_current()->get_id();
-       } else {
+       else
                nextThread = get_next_replay_thread();
-       }
 
        Node *currnode = curr->get_node();
        Node *parnode = currnode->get_parent();
 
-       if (!parnode->backtrack_empty()||!currnode->read_from_empty()||!currnode->future_value_empty()||!currnode->promise_empty())
+       if (!parnode->backtrack_empty() || !currnode->read_from_empty() ||
+                 !currnode->future_value_empty() || !currnode->promise_empty())
                if (!next_backtrack || *curr > *next_backtrack)
                        next_backtrack = curr;
 
@@ -366,13 +365,13 @@ bool ModelChecker::isfeasible() {
 
 /** Returns whether the current completed trace is feasible. */
 bool ModelChecker::isfinalfeasible() {
-       return isfeasible() && promises->size()==0;
+       return isfeasible() && promises->size() == 0;
 }
 
 /** Close out a RMWR by converting previous RMWR into a RMW or READ. */
 ModelAction * ModelChecker::process_rmw(ModelAction * act) {
        int tid = id_to_int(act->get_tid());
-       ModelAction *lastread=get_last_action(tid);
+       ModelAction *lastread = get_last_action(tid);
        lastread->process_rmw(act);
        if (act->is_rmw())
                cyclegraph->addRMWEdge(lastread, lastread->get_reads_from());
@@ -385,7 +384,7 @@ ModelAction * ModelChecker::process_rmw(ModelAction * act) {
  * @param rf The action that curr reads from. Must be a write.
  */
 void ModelChecker::r_modification_order(ModelAction * curr, const ModelAction *rf) {
-       std::vector<action_list_t> *thrd_lists = obj_thrd_map->ensureptr(curr->get_location());
+       std::vector<action_list_t> *thrd_lists = obj_thrd_map->get_safe_ptr(curr->get_location());
        unsigned int i;
        ASSERT(curr->is_read());
 
@@ -400,10 +399,10 @@ void ModelChecker::r_modification_order(ModelAction * curr, const ModelAction *r
                        /* Include at most one act per-thread that "happens before" curr */
                        if (act->happens_before(curr)) {
                                if (act->is_read()) {
-                                       const ModelAction * prevreadfrom=act->get_reads_from();
-                                       if (prevreadfrom!=NULL&&rf!=prevreadfrom)
+                                       const ModelAction * prevreadfrom = act->get_reads_from();
+                                       if (prevreadfrom != NULL && rf != prevreadfrom)
                                                cyclegraph->addEdge(rf, prevreadfrom);
-                               } else if (rf!=act) {
+                               } else if (rf != act) {
                                        cyclegraph->addEdge(rf, act);
                                }
                                break;
@@ -415,7 +414,7 @@ void ModelChecker::r_modification_order(ModelAction * curr, const ModelAction *r
 /** Updates the cyclegraph with the constraints imposed from the
  *  current read. */
 void ModelChecker::post_r_modification_order(ModelAction * curr, const ModelAction *rf) {
-       std::vector<action_list_t> *thrd_lists = obj_thrd_map->ensureptr(curr->get_location());
+       std::vector<action_list_t> *thrd_lists = obj_thrd_map->get_safe_ptr(curr->get_location());
        unsigned int i;
        ASSERT(curr->is_read());
 
@@ -424,24 +423,24 @@ void ModelChecker::post_r_modification_order(ModelAction * curr, const ModelActi
                /* Iterate over actions in thread, starting from most recent */
                action_list_t *list = &(*thrd_lists)[i];
                action_list_t::reverse_iterator rit;
-               ModelAction *lastact=NULL;
+               ModelAction *lastact = NULL;
 
                /* Find last action that happens after curr */
                for (rit = list->rbegin(); rit != list->rend(); rit++) {
                        ModelAction *act = *rit;
                        if (curr->happens_before(act)) {
-                               lastact=act;
+                               lastact = act;
                        } else
                                break;
                }
 
                        /* Include at most one act per-thread that "happens before" curr */
-               if (lastact!=NULL) {
+               if (lastact != NULL) {
                        if (lastact->is_read()) {
-                               const ModelAction * postreadfrom=lastact->get_reads_from();
-                               if (postreadfrom!=NULL&&rf!=postreadfrom)
+                               const ModelAction * postreadfrom = lastact->get_reads_from();
+                               if (postreadfrom != NULL&&rf != postreadfrom)
                                        cyclegraph->addEdge(postreadfrom, rf);
-                       } else if (rf!=lastact) {
+                       } else if (rf != lastact) {
                                cyclegraph->addEdge(lastact, rf);
                        }
                        break;
@@ -454,15 +453,15 @@ void ModelChecker::post_r_modification_order(ModelAction * curr, const ModelActi
  * @param curr The current action. Must be a write.
  */
 void ModelChecker::w_modification_order(ModelAction * curr) {
-       std::vector<action_list_t> *thrd_lists = obj_thrd_map->ensureptr(curr->get_location());
+       std::vector<action_list_t> *thrd_lists = obj_thrd_map->get_safe_ptr(curr->get_location());
        unsigned int i;
        ASSERT(curr->is_write());
 
        if (curr->is_seqcst()) {
                /* We have to at least see the last sequentially consistent write,
                         so we are initialized. */
-               ModelAction * last_seq_cst=get_last_seq_cst(curr->get_location());
-               if (last_seq_cst!=NULL)
+               ModelAction * last_seq_cst = get_last_seq_cst(curr->get_location());
+               if (last_seq_cst != NULL)
                        cyclegraph->addEdge(curr, last_seq_cst);
        }
 
@@ -476,25 +475,24 @@ void ModelChecker::w_modification_order(ModelAction * curr) {
 
                        /* Include at most one act per-thread that "happens before" curr */
                        if (act->happens_before(curr)) {
-                               if (act->is_read()) {
+                               if (act->is_read())
                                        cyclegraph->addEdge(curr, act->get_reads_from());
-                               else
+                               else
                                        cyclegraph->addEdge(curr, act);
                                break;
-                       } else {
-                               if (act->is_read()&&!act->is_synchronizing(curr)&&!act->same_thread(curr)) {
-                                       /* We have an action that:
-                                                (1) did not happen before us
-                                                (2) is a read and we are a write
-                                                (3) cannot synchronize with us
-                                                (4) is in a different thread
-                                                =>
-                                                that read could potentially read from our write.
-                                       */
-                                       if (act->get_node()->add_future_value(curr->get_value())&&
-                                                       (!next_backtrack || *act > * next_backtrack))
-                                               next_backtrack = act;
-                               }
+                       } else if (act->is_read() && !act->is_synchronizing(curr) &&
+                                                    !act->same_thread(curr)) {
+                               /* We have an action that:
+                                  (1) did not happen before us
+                                  (2) is a read and we are a write
+                                  (3) cannot synchronize with us
+                                  (4) is in a different thread
+                                  =>
+                                  that read could potentially read from our write.
+                                */
+                               if (act->get_node()->add_future_value(curr->get_value()) &&
+                                               (!next_backtrack || *act > *next_backtrack))
+                                       next_backtrack = act;
                        }
                }
        }
@@ -512,9 +510,9 @@ void ModelChecker::add_action_to_lists(ModelAction *act)
        int tid = id_to_int(act->get_tid());
        action_trace->push_back(act);
 
-       obj_map->ensureptr(act->get_location())->push_back(act);
+       obj_map->get_safe_ptr(act->get_location())->push_back(act);
 
-       std::vector<action_list_t> *vec = obj_thrd_map->ensureptr(act->get_location());
+       std::vector<action_list_t> *vec = obj_thrd_map->get_safe_ptr(act->get_location());
        if (tid >= (int)vec->size())
                vec->resize(next_thread_id);
        (*vec)[tid].push_back(act);
@@ -540,7 +538,7 @@ ModelAction * ModelChecker::get_last_action(thread_id_t tid)
  */
 ModelAction * ModelChecker::get_last_seq_cst(const void *location)
 {
-       action_list_t *list = obj_map->ensureptr(location);
+       action_list_t *list = obj_map->get_safe_ptr(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 != list->rend(); rit++)
@@ -570,10 +568,10 @@ ClockVector * ModelChecker::get_cv(thread_id_t tid) {
 /** Resolve the given promises. */
 
 void ModelChecker::resolve_promises(ModelAction *write) {
-       for(unsigned int i=0, promise_index=0;promise_index<promises->size(); i++) {
-               Promise * promise=(*promises)[promise_index];
+       for (unsigned int i = 0, promise_index = 0;promise_index<promises->size(); i++) {
+               Promise * promise = (*promises)[promise_index];
                if (write->get_node()->get_promise(i)) {
-                       ModelAction * read=promise->get_action();
+                       ModelAction * read = promise->get_action();
                        read->read_from(write);
                        r_modification_order(read, write);
                        post_r_modification_order(read, write);
@@ -587,14 +585,14 @@ void ModelChecker::resolve_promises(ModelAction *write) {
  *  this action. */
 
 void ModelChecker::compute_promises(ModelAction *curr) {
-       for(unsigned int i=0;i<promises->size();i++) {
-               Promise * promise=(*promises)[i];
-               const ModelAction * act=promise->get_action();
+       for (unsigned int i = 0;i<promises->size();i++) {
+               Promise * promise = (*promises)[i];
+               const ModelAction * act = promise->get_action();
                if (!act->happens_before(curr)&&
                                act->is_read()&&
                                !act->is_synchronizing(curr)&&
                                !act->same_thread(curr)&&
-                               promise->get_value()==curr->get_value()) {
+                               promise->get_value() == curr->get_value()) {
                        curr->get_node()->set_promise(i);
                }
        }
@@ -603,14 +601,14 @@ void ModelChecker::compute_promises(ModelAction *curr) {
 /** Checks promises in response to change in ClockVector Threads. */
 
 void ModelChecker::check_promises(ClockVector *old_cv, ClockVector * merge_cv) {
-       for(unsigned int i=0;i<promises->size();i++) {
-               Promise * promise=(*promises)[i];
-               const ModelAction * act=promise->get_action();
-               if ((old_cv==NULL||!old_cv->synchronized_since(act))&&
+       for (unsigned int i = 0;i<promises->size();i++) {
+               Promise * promise = (*promises)[i];
+               const ModelAction * act = promise->get_action();
+               if ((old_cv == NULL||!old_cv->synchronized_since(act))&&
                                merge_cv->synchronized_since(act)) {
                        //This thread is no longer able to send values back to satisfy the promise
-                       int num_synchronized_threads=promise->increment_threads();
-                       if (num_synchronized_threads==model->get_num_threads()) {
+                       int num_synchronized_threads = promise->increment_threads();
+                       if (num_synchronized_threads == model->get_num_threads()) {
                                //Promise has failed
                                failed_promise = true;
                                return;
@@ -628,7 +626,7 @@ void ModelChecker::check_promises(ClockVector *old_cv, ClockVector * merge_cv) {
  */
 void ModelChecker::build_reads_from_past(ModelAction *curr)
 {
-       std::vector<action_list_t> *thrd_lists = obj_thrd_map->ensureptr(curr->get_location());
+       std::vector<action_list_t> *thrd_lists = obj_thrd_map->get_safe_ptr(curr->get_location());
        unsigned int i;
        ASSERT(curr->is_read());
 
@@ -704,7 +702,7 @@ static void print_list(action_list_t *list)
        printf("---------------------------------------------------------------------\n");
 }
 
-void ModelChecker::print_summary(void)
+void ModelChecker::print_summary()
 {
        printf("\n");
        printf("Number of executions: %d\n", num_executions);
@@ -718,11 +716,15 @@ void ModelChecker::print_summary(void)
        printf("\n");
 }
 
-int ModelChecker::add_thread(Thread *t)
+/**
+ * Add a Thread to the system for the first time. Should only be called once
+ * per thread.
+ * @param t The Thread to add
+ */
+void ModelChecker::add_thread(Thread *t)
 {
        thread_map->put(id_to_int(t->get_id()), t);
        scheduler->add_thread(t);
-       return 0;
 }
 
 void ModelChecker::remove_thread(Thread *t)
@@ -747,5 +749,48 @@ int ModelChecker::switch_to_master(ModelAction *act)
        Thread * old = thread_current();
        set_current_action(act);
        old->set_state(THREAD_READY);
-       return Thread::swap(old, get_system_context());
+       return Thread::swap(old, &system_context);
+}
+
+/**
+ * Takes the next step in the execution, if possible.
+ * @return Returns true (success) if a step was taken and false otherwise.
+ */
+bool ModelChecker::take_step() {
+       Thread *curr, *next;
+
+       curr = thread_current();
+       if (curr) {
+               if (curr->get_state() == THREAD_READY) {
+                       check_current_action();
+                       scheduler->add_thread(curr);
+               } else if (curr->get_state() == THREAD_RUNNING) {
+                       /* Stopped while running; i.e., completed */
+                       curr->complete();
+               } else {
+                       ASSERT(false);
+               }
+       }
+       next = scheduler->next_thread();
+
+       /* Infeasible -> don't take any more steps */
+       if (!isfeasible())
+               return false;
+
+       if (next)
+               next->set_state(THREAD_RUNNING);
+       DEBUG("(%d, %d)\n", curr ? curr->get_id() : -1, next ? next->get_id() : -1);
+
+       /* next == NULL -> don't take any more steps */
+       if (!next)
+               return false;
+       /* Return false only if swap fails with an error */
+       return (Thread::swap(&system_context, next) == 0);
+}
+
+/** Runs the current execution until threre are no more steps to take. */
+void ModelChecker::finish_execution() {
+       DBG();
+
+       while (take_step());
 }