X-Git-Url: http://plrg.eecs.uci.edu/git/?a=blobdiff_plain;f=action.cc;h=c96949bc906cc02a9ca3cb50af761a92feda94c7;hb=f291abaf7a05ebdc5981072212b55265dafc1c4a;hp=b0d8fc9b7bed4aaacc843cc8620c0abfffc1dd00;hpb=1a75079a60d2788bad4ee82378182abcfade51c8;p=c11tester.git

diff --git a/action.cc b/action.cc
index b0d8fc9b..c96949bc 100644
--- a/action.cc
+++ b/action.cc
@@ -5,19 +5,17 @@
 #include "clockvector.h"
 #include "common.h"
 
-ModelAction::ModelAction(action_type_t type, memory_order order, void *loc, int value)
+ModelAction::ModelAction(action_type_t type, memory_order order, void *loc, int value) :
+	type(type),
+	order(order),
+	location(loc),
+	value(value),
+	reads_from(NULL),
+	cv(NULL)
 {
 	Thread *t = thread_current();
-	ModelAction *act = this;
-
-	act->type = type;
-	act->order = order;
-	act->location = loc;
-	act->tid = t->get_id();
-	act->value = value;
-	act->seq_number = model->get_next_seq_num();
-
-	cv = NULL;
+	this->tid = t->get_id();
+	this->seq_number = model->get_next_seq_num();
 }
 
 ModelAction::~ModelAction()
@@ -26,17 +24,27 @@ ModelAction::~ModelAction()
 		delete cv;
 }
 
-bool ModelAction::is_read()
+bool ModelAction::is_read() const
 {
 	return type == ATOMIC_READ;
 }
 
-bool ModelAction::is_write()
+bool ModelAction::is_write() const
+{
+	return type == ATOMIC_WRITE || type == ATOMIC_INIT;
+}
+
+bool ModelAction::is_rmw() const
 {
-	return type == ATOMIC_WRITE;
+	return type == ATOMIC_RMW;
 }
 
-bool ModelAction::is_acquire()
+bool ModelAction::is_initialization() const
+{
+	return type == ATOMIC_INIT;
+}
+
+bool ModelAction::is_acquire() const
 {
 	switch (order) {
 	case memory_order_acquire:
@@ -48,7 +56,7 @@ bool ModelAction::is_acquire()
 	}
 }
 
-bool ModelAction::is_release()
+bool ModelAction::is_release() const
 {
 	switch (order) {
 	case memory_order_release:
@@ -60,46 +68,87 @@ bool ModelAction::is_release()
 	}
 }
 
-bool ModelAction::same_var(ModelAction *act)
+bool ModelAction::is_seqcst() const
+{
+	return order==memory_order_seq_cst;
+}
+
+bool ModelAction::same_var(const ModelAction *act) const
 {
 	return location == act->location;
 }
 
-bool ModelAction::same_thread(ModelAction *act)
+bool ModelAction::same_thread(const ModelAction *act) const
 {
 	return tid == act->tid;
 }
 
-bool ModelAction::is_dependent(ModelAction *act)
+/** The is_synchronizing method should only explore interleavings if:
+ *  (1) the operations are seq_cst and don't commute or
+ *  (2) the reordering may establish or break a synchronization relation.
+ *  Other memory operations will be dealt with by using the reads_from
+ *  relation.
+ *
+ *  @param act is the action to consider exploring a reordering.
+ *  @return tells whether we have to explore a reordering.
+ */
+
+bool ModelAction::is_synchronizing(const ModelAction *act) const
 {
-	if (!is_read() && !is_write())
+	//Same thread can't be reordered
+	if (same_thread(act))
 		return false;
-	if (!act->is_read() && !act->is_write())
+
+	// Different locations commute
+	if (!same_var(act))
 		return false;
-	if (same_var(act) && !same_thread(act) &&
-			(is_write() || act->is_write()))
+	
+	// Explore interleavings of seqcst writes to guarantee total order
+	// of seq_cst operations that don't commute
+	if (is_write() && is_seqcst() && act->is_write() && act->is_seqcst())
+		return true;
+
+	// Explore synchronizing read/write pairs
+	if (is_read() && is_acquire() && act->is_write() && act->is_release())
 		return true;
+	if (is_write() && is_release() && act->is_read() && act->is_acquire())
+		return true;
+
+	// Otherwise handle by reads_from relation
 	return false;
 }
 
-void ModelAction::create_cv(ModelAction *parent)
+void ModelAction::create_cv(const ModelAction *parent)
 {
 	ASSERT(cv == NULL);
+
 	if (parent)
 		cv = new ClockVector(parent->cv, this);
 	else
-		cv = new ClockVector();
+		cv = new ClockVector(NULL, this);
 }
 
-void ModelAction::read_from(ModelAction *act)
+void ModelAction::read_from(const ModelAction *act)
 {
 	ASSERT(cv);
 	if (act->is_release() && this->is_acquire())
 		cv->merge(act->cv);
+	reads_from = act;
 	value = act->value;
 }
 
-void ModelAction::print(void)
+/**
+ * Check whether 'this' happens before act, according to the memory-model's
+ * happens before relation. This is checked via the ClockVector constructs.
+ * @return true if this action's thread has synchronized with act's thread
+ * since the execution of act, false otherwise.
+ */
+bool ModelAction::happens_before(const ModelAction *act) const
+{
+	return act->cv->synchronized_since(this);
+}
+
+void ModelAction::print(void) const
 {
 	const char *type_str;
 	switch (this->type) {
@@ -118,10 +167,23 @@ void ModelAction::print(void)
 	case ATOMIC_WRITE:
 		type_str = "atomic write";
 		break;
+	case ATOMIC_RMW:
+		type_str = "atomic rmw";
+		break;
+	case ATOMIC_INIT:
+		type_str = "init atomic";
+		break;
 	default:
 		type_str = "unknown type";
 	}
 
-	printf("(%4d) Thread: %d\tAction: %s\tMO: %d\tLoc: %14p\tValue: %d\n",
+	printf("(%3d) Thread: %-2d    Action: %-13s    MO: %d    Loc: %14p    Value: %-4d",
 			seq_number, id_to_int(tid), type_str, order, location, value);
+	if (reads_from)
+		printf(" Rf: %d", reads_from->get_seq_number());
+	if (cv) {
+		printf("\t");
+		cv->print();
+	} else
+		printf("\n");
 }