+
+ /* erase p_node */
+ readerToPromiseNode.put(promise->get_action(), NULL);
+ delete p_node;
+
+ return !hasCycles;
+}
+
+/**
+ * Adds an edge between two CycleNodes.
+ * @param fromnode The edge comes from this CycleNode
+ * @param tonode The edge points to this CycleNode
+ */
+void CycleGraph::addNodeEdge(CycleNode *fromnode, CycleNode *tonode)
+{
+ if (!hasCycles)
+ hasCycles = checkReachable(tonode, fromnode);
+
+ if (fromnode->addEdge(tonode))
+ rollbackvector.push_back(fromnode);
+
+ /*
+ * If the fromnode has a rmwnode that is not the tonode, we should add
+ * an edge between its rmwnode and the tonode
+ */
+ CycleNode *rmwnode = fromnode->getRMW();
+ if (rmwnode && rmwnode != tonode) {
+ if (!hasCycles)
+ hasCycles = checkReachable(tonode, rmwnode);
+
+ if (rmwnode->addEdge(tonode))
+ rollbackvector.push_back(rmwnode);
+ }
+}
+
+/**
+ * @brief Add an edge between a write and the RMW which reads from it
+ *
+ * Handles special case of a RMW action, where the ModelAction rmw reads from
+ * the ModelAction from. The key differences are:
+ * (1) no write can occur in between the rmw and the from action.
+ * (2) Only one RMW action can read from a given write.
+ *
+ * @param from The edge comes from this ModelAction
+ * @param rmw The edge points to this ModelAction; this action must read from
+ * ModelAction from
+ */
+void CycleGraph::addRMWEdge(const ModelAction *from, const ModelAction *rmw)
+{
+ ASSERT(from);
+ ASSERT(rmw);
+
+ CycleNode *fromnode = getNode(from);
+ CycleNode *rmwnode = getNode(rmw);
+
+ /* Two RMW actions cannot read from the same write. */
+ if (fromnode->setRMW(rmwnode))
+ hasCycles = true;
+ else
+ rmwrollbackvector.push_back(fromnode);
+
+ /* Transfer all outgoing edges from the from node to the rmw node */
+ /* This process should not add a cycle because either:
+ * (1) The rmw should not have any incoming edges yet if it is the
+ * new node or
+ * (2) the fromnode is the new node and therefore it should not
+ * have any outgoing edges.
+ */
+ for (unsigned int i = 0; i < fromnode->getNumEdges(); i++) {
+ CycleNode *tonode = fromnode->getEdge(i);
+ if (tonode != rmwnode) {
+ if (rmwnode->addEdge(tonode))
+ rollbackvector.push_back(rmwnode);
+ }
+ }
+
+ addNodeEdge(fromnode, rmwnode);
+}
+
+#if SUPPORT_MOD_ORDER_DUMP
+void CycleGraph::dumpNodes(FILE *file) const
+{
+ for (unsigned int i = 0; i < nodeList.size(); i++) {
+ CycleNode *cn = nodeList[i];
+ const ModelAction *action = cn->getAction();
+ fprintf(file, "N%u [label=\"%u, T%u\"];\n", action->get_seq_number(), action->get_seq_number(), action->get_tid());
+ if (cn->getRMW() != NULL) {
+ fprintf(file, "N%u -> N%u[style=dotted];\n", action->get_seq_number(), cn->getRMW()->getAction()->get_seq_number());
+ }
+ for (unsigned int j = 0; j < cn->getNumEdges(); j++) {
+ CycleNode *dst = cn->getEdge(j);
+ const ModelAction *dstaction = dst->getAction();
+ fprintf(file, "N%u -> N%u;\n", action->get_seq_number(), dstaction->get_seq_number());
+ }
+ }
+}
+
+void CycleGraph::dumpGraphToFile(const char *filename) const
+{
+ char buffer[200];
+ sprintf(buffer, "%s.dot", filename);
+ FILE *file = fopen(buffer, "w");
+ fprintf(file, "digraph %s {\n", filename);
+ dumpNodes(file);
+ fprintf(file, "}\n");
+ fclose(file);
+}
+#endif
+
+/**
+ * Checks whether one ModelAction can reach another ModelAction/Promise
+ * @param from The ModelAction from which to begin exploration
+ * @param to The ModelAction or Promise to reach
+ * @return True, @a from can reach @a to; otherwise, false
+ */
+template <typename T>
+bool CycleGraph::checkReachable(const ModelAction *from, const T *to) const
+{
+ CycleNode *fromnode = actionToNode.get(from);
+ CycleNode *tonode = actionToNode.get(to);
+
+ if (!fromnode || !tonode)
+ return false;
+
+ return checkReachable(fromnode, tonode);