X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=action.cc;h=a11467587901f258a03b9e11623403f60f3d1263;hb=24032577ab44f5adb4f072d022f70d0b0162ab90;hp=1387ed15b67c9ac25d7fcba68491bbb72d8ff236;hpb=15fabc6f4e6591341940a8087a8dd088af59bb5c;p=model-checker.git

diff --git a/action.cc b/action.cc
index 1387ed1..a114675 100644
--- a/action.cc
+++ b/action.cc
@@ -31,13 +31,14 @@ ModelAction::ModelAction(action_type_t type, memory_order order, void *loc,
 	location(loc),
 	value(value),
 	reads_from(NULL),
+	last_fence_release(NULL),
 	node(NULL),
 	seq_number(ACTION_INITIAL_CLOCK),
 	cv(NULL),
 	sleep_flag(false)
 {
 	/* References to NULL atomic variables can end up here */
-	ASSERT(loc || type == MODEL_FIXUP_RELSEQ);
+	ASSERT(loc || type == ATOMIC_FENCE || type == MODEL_FIXUP_RELSEQ);
 
 	Thread *t = thread ? thread : thread_current();
 	this->tid = t->get_id();
@@ -65,10 +66,17 @@ void ModelAction::copy_from_new(ModelAction *newaction)
 
 void ModelAction::set_seq_number(modelclock_t num)
 {
+	/* ATOMIC_UNINIT actions should never have non-zero clock */
+	ASSERT(!is_uninitialized());
 	ASSERT(seq_number == ACTION_INITIAL_CLOCK);
 	seq_number = num;
 }
 
+bool ModelAction::is_thread_start() const
+{
+	return type == THREAD_START;
+}
+
 bool ModelAction::is_relseq_fixup() const
 {
 	return type == MODEL_FIXUP_RELSEQ;
@@ -116,6 +124,17 @@ bool ModelAction::is_failed_trylock() const
 	return (type == ATOMIC_TRYLOCK && value == VALUE_TRYFAILED);
 }
 
+/** @return True if this operation is performed on a C/C++ atomic variable */
+bool ModelAction::is_atomic_var() const
+{
+	return is_read() || could_be_write();
+}
+
+bool ModelAction::is_uninitialized() const
+{
+	return type == ATOMIC_UNINIT;
+}
+
 bool ModelAction::is_read() const
 {
 	return type == ATOMIC_READ || type == ATOMIC_RMWR || type == ATOMIC_RMW;
@@ -123,7 +142,7 @@ bool ModelAction::is_read() const
 
 bool ModelAction::is_write() const
 {
-	return type == ATOMIC_WRITE || type == ATOMIC_RMW || type == ATOMIC_INIT;
+	return type == ATOMIC_WRITE || type == ATOMIC_RMW || type == ATOMIC_INIT || type == ATOMIC_UNINIT;
 }
 
 bool ModelAction::could_be_write() const
@@ -156,6 +175,11 @@ bool ModelAction::is_initialization() const
 	return type == ATOMIC_INIT;
 }
 
+bool ModelAction::is_relaxed() const
+{
+	return order == std::memory_order_relaxed;
+}
+
 bool ModelAction::is_acquire() const
 {
 	switch (order) {
@@ -240,7 +264,7 @@ void ModelAction::process_rmw(ModelAction * act) {
  */
 bool ModelAction::could_synchronize_with(const ModelAction *act) const
 {
-	//Same thread can't be reordered
+	// Same thread can't be reordered
 	if (same_thread(act))
 		return false;
 
@@ -248,24 +272,26 @@ bool ModelAction::could_synchronize_with(const ModelAction *act) const
 	if (!same_var(act))
 		return false;
 
-	// Explore interleavings of seqcst writes to guarantee total order
-	// of seq_cst operations that don't commute
-	if ((could_be_write() || act->could_be_write()) && is_seqcst() && act->is_seqcst())
+	// Explore interleavings of seqcst writes/fences to guarantee total
+	// order of seq_cst operations that don't commute
+	if ((could_be_write() || act->could_be_write() || is_fence() || act->is_fence())
+			&& is_seqcst() && act->is_seqcst())
 		return true;
 
-	// Explore synchronizing read/write pairs
-	if (is_read() && is_acquire() && act->could_be_write() && act->is_release())
+	// Explore synchronizing read/write/fence pairs
+	if (is_acquire() && act->is_release() && (is_read() || is_fence()) &&
+			(act->could_be_write() || act->is_fence()))
 		return true;
 
-	//lock just released...we can grab lock
+	// lock just released...we can grab lock
 	if ((is_lock() ||is_trylock()) && (act->is_unlock()||act->is_wait()))
 		return true;
 
-	//lock just acquired...we can fail to grab lock
+	// lock just acquired...we can fail to grab lock
 	if (is_trylock() && act->is_success_lock())
 		return true;
 
-	//other thread stalling on lock...we can release lock
+	// other thread stalling on lock...we can release lock
 	if (is_unlock() && (act->is_trylock()||act->is_lock()))
 		return true;
 
@@ -284,19 +310,19 @@ bool ModelAction::could_synchronize_with(const ModelAction *act) const
 
 bool ModelAction::is_conflicting_lock(const ModelAction *act) const
 {
-	//Must be different threads to reorder
+	// Must be different threads to reorder
 	if (same_thread(act))
 		return false;
 	
-	//Try to reorder a lock past a successful lock
+	// Try to reorder a lock past a successful lock
 	if (act->is_success_lock())
 		return true;
 	
-	//Try to push a successful trylock past an unlock
+	// Try to push a successful trylock past an unlock
 	if (act->is_unlock() && is_trylock() && value == VALUE_TRYSUCCESS)
 		return true;
 
-	//Try to push a successful trylock past a wait
+	// Try to push a successful trylock past a wait
 	if (act->is_wait() && is_trylock() && value == VALUE_TRYSUCCESS)
 		return true;
 
@@ -326,27 +352,23 @@ void ModelAction::set_try_lock(bool obtainedlock) {
 		value=VALUE_TRYFAILED;
 }
 
+/** @return The Node associated with this ModelAction */
+Node * ModelAction::get_node() const
+{
+	/* UNINIT actions do not have a Node */
+	ASSERT(!is_uninitialized());
+	return node;
+}
+
 /**
  * Update the model action's read_from action
  * @param act The action to read from; should be a write
- * @return True if this read established synchronization
  */
-bool ModelAction::read_from(const ModelAction *act)
+void ModelAction::set_read_from(const ModelAction *act)
 {
-	ASSERT(cv);
 	reads_from = act;
-	if (act != NULL && this->is_acquire()) {
-		rel_heads_list_t release_heads;
-		model->get_release_seq_heads(this, &release_heads);
-		int num_heads = release_heads.size();
-		for (unsigned int i = 0; i < release_heads.size(); i++)
-			if (!synchronize_with(release_heads[i])) {
-				model->set_bad_synchronization();
-				num_heads--;
-			}
-		return num_heads > 0;
-	}
-	return false;
+	if (act && act->is_uninitialized())
+		model->assert_bug("May read from uninitialized atomic\n");
 }
 
 /**
@@ -402,6 +424,9 @@ void ModelAction::print() const
 	case THREAD_FINISH:
 		type_str = "thread finish";
 		break;
+	case ATOMIC_UNINIT:
+		type_str = "uninitialized";
+		break;
 	case ATOMIC_READ:
 		type_str = "atomic read";
 		break;
@@ -445,7 +470,11 @@ void ModelAction::print() const
 		type_str = "unknown type";
 	}
 
-	uint64_t valuetoprint=type==ATOMIC_READ?(reads_from!=NULL?reads_from->value:VALUE_NONE):value;
+	uint64_t valuetoprint;
+	if (type == ATOMIC_READ && reads_from != NULL)
+		valuetoprint = reads_from->value;
+	else
+		valuetoprint = value;
 
 	switch (this->order) {
 	case std::memory_order_relaxed:
@@ -468,22 +497,22 @@ void ModelAction::print() const
 		break;
 	}
 
-	printf("(%4d) Thread: %-2d   Action: %-13s   MO: %7s  Loc: %14p   Value: %-#18" PRIx64,
+	model_print("(%4d) Thread: %-2d   Action: %-13s   MO: %7s  Loc: %14p   Value: %-#18" PRIx64,
 			seq_number, id_to_int(tid), type_str, mo_str, location, valuetoprint);
 	if (is_read()) {
 		if (reads_from)
-			printf("  Rf: %-3d", reads_from->get_seq_number());
+			model_print("  Rf: %-3d", reads_from->get_seq_number());
 		else
-			printf("  Rf: ?  ");
+			model_print("  Rf: ?  ");
 	}
 	if (cv) {
 		if (is_read())
-			printf(" ");
+			model_print(" ");
 		else
-			printf("          ");
+			model_print("          ");
 		cv->print();
 	} else
-		printf("\n");
+		model_print("\n");
 }
 
 /** @brief Print nicely-formatted info about this ModelAction */