Rework how we present non-SC traces...previous presentation didn't make reasons clear.
[model-checker.git] / scanalysis.cc
index daf41f8a19ba4395d61dff065f71422a422547dc..75aed1aa80ed994985fee2b67ff69e83b37a67cb 100644 (file)
@@ -6,7 +6,9 @@
 
 SCAnalysis::SCAnalysis(const ModelExecution *execution) :
        cvmap(),
-       cycleset(),
+       cyclic(false),
+       badrfset(),
+       lastwrmap(),
        threadlists(1),
        execution(execution)
 {
@@ -16,18 +18,21 @@ SCAnalysis::~SCAnalysis() {
 }
 
 void SCAnalysis::print_list(action_list_t *list) {
-       action_list_t::iterator it;
-
        model_print("---------------------------------------------------------------------\n");
-
+       if (cyclic)
+               model_print("Not SC\n");
        unsigned int hash = 0;
 
-       for (it = list->begin(); it != list->end(); it++) {
+       for (action_list_t::iterator it = list->begin(); it != list->end(); it++) {
                const ModelAction *act = *it;
                if (act->get_seq_number() > 0) {
-                       if (cycleset.contains(act))
-                               model_print("CYC");
+                       if (badrfset.contains(act))
+                               model_print("BRF ");
                        act->print();
+                       cvmap.get(act)->print();
+                       if (badrfset.contains(act)) {
+                               model_print("DESIRED %u \n",badrfset.get(act)->get_seq_number());
+                       }
                }
                hash = hash ^ (hash << 3) ^ ((*it)->hash());
        }
@@ -39,25 +44,45 @@ void SCAnalysis::analyze(action_list_t *actions) {
        buildVectors(actions);
        computeCV(actions);
        action_list_t *list = generateSC(actions);
+       check_rf(list);
        print_list(list);
 }
 
-bool SCAnalysis::merge(ClockVector *cv, const ModelAction *act, ClockVector *cv2) {
+void SCAnalysis::check_rf(action_list_t *list) {
+       for (action_list_t::iterator it = list->begin(); it != list->end(); it++) {
+               const ModelAction *act = *it;
+               if (act->is_read()) {
+                       if (act->get_reads_from()!=lastwrmap.get(act->get_location()))
+                               badrfset.put(act,lastwrmap.get(act->get_location()));
+               }
+               if (act->is_write())
+                       lastwrmap.put(act->get_location(), act);
+       }
+}
+
+bool SCAnalysis::merge(ClockVector *cv, const ModelAction *act, const ModelAction *act2) {
+       ClockVector * cv2=cvmap.get(act2);
+       if (cv2==NULL)
+               return true;
        if (cv2->getClock(act->get_tid()) >= act->get_seq_number() && act->get_seq_number() != 0) {
-               cycleset.put(act, act);
+               cyclic=true;
+               //refuse to introduce cycles into clock vectors
+               return false;
        }
+
        return cv->merge(cv2);
 }
 
 ModelAction * SCAnalysis::getNextAction() {
        ModelAction *act = NULL;
+       /* Find the earliest in SC ordering */
        for (int i = 0; i <= maxthreads; i++) {
                action_list_t *threadlist = &threadlists[i];
                if (threadlist->empty())
                        continue;
                ModelAction *first = threadlist->front();
-               if (act == NULL) {
-                       act = first;
+               if (act==NULL) {
+                       act=first;
                        continue;
                }
                ClockVector *cv = cvmap.get(act);
@@ -67,29 +92,35 @@ ModelAction * SCAnalysis::getNextAction() {
        }
        if (act == NULL)
                return act;
-       //print cycles in a nice way to avoid confusion
-       //make sure thread starts appear after the create
-       if (act->is_thread_start()) {
-               ModelAction *createact = execution->get_thread(act)->get_creation();
-               if (createact) {
-                       action_list_t *threadlist = &threadlists[id_to_int(createact->get_tid())];
-                       if (!threadlist->empty()) {
-                               ModelAction *first = threadlist->front();
-                               if (first->get_seq_number() <= createact->get_seq_number())
-                                       act = first;
-                       }
+
+
+       /* Find the model action with the earliest sequence number in case of a cycle.
+        */
+
+       for (int i = 0; i <= maxthreads; i++) {
+               action_list_t *threadlist = &threadlists[i];
+               if (threadlist->empty())
+                       continue;
+               ModelAction *first = threadlist->front();
+               ClockVector *cv = cvmap.get(act);
+               ClockVector *cvfirst = cvmap.get(first);
+               if (first->get_seq_number()<act->get_seq_number()&&
+                               (cv->synchronized_since(first)||!cvfirst->synchronized_since(act))) {
+                       act=first;
                }
        }
 
-       //make sure that joins appear after the thread is finished
-       if (act->is_thread_join()) {
-               int jointhread = id_to_int(act->get_thread_operand()->get_id());
-               action_list_t *threadlist = &threadlists[jointhread];
-               if (!threadlist->empty()) {
-                       act = threadlist->front();
+       /* See if hb demands an earlier action. */
+       for (int i = 0; i <= maxthreads; i++) {
+               action_list_t *threadlist = &threadlists[i];
+               if (threadlist->empty())
+                       continue;
+               ModelAction *first = threadlist->front();
+               ClockVector *cv = act->get_cv();
+               if (cv->synchronized_since(first)) {
+                       act = first;
                }
        }
-
        return act;
 }
 
@@ -128,7 +159,6 @@ void SCAnalysis::buildVectors(action_list_t *list) {
 
 bool SCAnalysis::updateConstraints(ModelAction *act) {
        bool changed = false;
-       ClockVector *actcv = cvmap.get(act);
        for (int i = 0; i <= maxthreads; i++) {
                thread_id_t tid = int_to_id(i);
                if (tid == act->get_tid())
@@ -144,7 +174,7 @@ bool SCAnalysis::updateConstraints(ModelAction *act) {
                                break;
                        if (write->get_location() == act->get_location()) {
                                //write is sc after act
-                               merge(writecv, write, actcv);
+                               merge(writecv, write, act);
                                changed = true;
                                break;
                        }
@@ -159,7 +189,7 @@ bool SCAnalysis::processRead(ModelAction *read, ClockVector *cv) {
        /* Merge in the clock vector from the write */
        const ModelAction *write = read->get_reads_from();
        ClockVector *writecv = cvmap.get(write);
-       changed |= writecv == NULL || (merge(cv, read, writecv) && (*read < *write));
+       changed |= merge(cv, read, write) && (*read < *write);
 
        for (int i = 0; i <= maxthreads; i++) {
                thread_id_t tid = int_to_id(i);
@@ -183,7 +213,7 @@ bool SCAnalysis::processRead(ModelAction *read, ClockVector *cv) {
                                 write -rf-> R =>
                                 R -sc-> write2 */
                        if (write2cv->synchronized_since(write)) {
-                               changed |= merge(write2cv, write2, cv);
+                               changed |= merge(write2cv, write2, read);
                        }
 
                        //looking for earliest write2 in iteration to satisfy this
@@ -191,7 +221,7 @@ bool SCAnalysis::processRead(ModelAction *read, ClockVector *cv) {
                                 write -rf-> R =>
                                 write2 -sc-> write */
                        if (cv->synchronized_since(write2)) {
-                               changed |= writecv == NULL || merge(writecv, write, write2cv);
+                               changed |= writecv==NULL || merge(writecv, write, write2);
                                break;
                        }
                }
@@ -212,20 +242,19 @@ void SCAnalysis::computeCV(action_list_t *list) {
                        ModelAction *lastact = last_act[id_to_int(act->get_tid())];
                        if (act->is_thread_start())
                                lastact = execution->get_thread(act)->get_creation();
-                       ClockVector *lastcv = (lastact != NULL) ? cvmap.get(lastact) : NULL;
                        last_act[id_to_int(act->get_tid())] = act;
                        ClockVector *cv = cvmap.get(act);
                        if (cv == NULL) {
-                               cv = new ClockVector(lastcv, act);
+                               cv = new ClockVector(NULL, act);
                                cvmap.put(act, cv);
-                       } else if (lastcv != NULL) {
-                               merge(cv, act, lastcv);
+                       }
+                       if (lastact != NULL) {
+                               merge(cv, act, lastact);
                        }
                        if (act->is_thread_join()) {
                                Thread *joinedthr = act->get_thread_operand();
                                ModelAction *finish = execution->get_last_action(joinedthr->get_id());
-                               ClockVector *finishcv = cvmap.get(finish);
-                               changed |= (finishcv == NULL) || merge(cv, act, finishcv);
+                               changed |= merge(cv, act, finish);
                        }
                        if (act->is_read()) {
                                changed |= processRead(act, cv);