#include "cyclegraph.h"
#include "action.h"
+#include "common.h"
/** Initializes a CycleGraph object. */
-
-CycleGraph::CycleGraph() {
- hasCycles=false;
+CycleGraph::CycleGraph() :
+ hasCycles(false),
+ oldCycles(false),
+ hasRMWViolation(false),
+ oldRMWViolation(false)
+{
}
-/** Returns the CycleNode for a given ModelAction. */
+/** CycleGraph destructor */
+CycleGraph::~CycleGraph() {
+}
-CycleNode * CycleGraph::getNode(ModelAction * action) {
+/**
+ * @brief Returns the CycleNode corresponding to a given ModelAction
+ * @param action The ModelAction to find a node for
+ * @return The CycleNode paired with this action
+ */
+CycleNode * CycleGraph::getNode(const ModelAction *action) {
CycleNode *node=actionToNode.get(action);
if (node==NULL) {
node=new CycleNode(action);
actionToNode.put(action, node);
+#if SUPPORT_MOD_ORDER_DUMP
+ nodeList.push_back(node);
+#endif
}
return node;
}
-/** Adds an edge between two ModelActions. */
+/**
+ * Adds an edge between two ModelActions. The ModelAction @a to is ordered
+ * after the ModelAction @a from.
+ * @param to The edge points to this ModelAction
+ * @param from The edge comes from this ModelAction
+ */
+void CycleGraph::addEdge(const ModelAction *from, const ModelAction *to) {
+ ASSERT(from);
+ ASSERT(to);
-void CycleGraph::addEdge(ModelAction *from, ModelAction *to) {
CycleNode *fromnode=getNode(from);
CycleNode *tonode=getNode(to);
+
if (!hasCycles) {
// Check for Cycles
- hasCycles=checkReachable(fromnode, tonode);
+ hasCycles=checkReachable(tonode, fromnode);
+ }
+
+ if (fromnode->addEdge(tonode))
+ rollbackvector.push_back(fromnode);
+
+
+ CycleNode * rmwnode=fromnode->getRMW();
+
+ //If the fromnode has a rmwnode that is not the tonode, we
+ //should add an edge between its rmwnode and the tonode
+
+ //If tonode is also a rmw, don't do this check as the execution is
+ //doomed and we'll catch the problem elsewhere, but we want to allow
+ //for the possibility of sending to's write value to rmwnode
+
+ if (rmwnode!=NULL&&!to->is_rmw()) {
+ if (!hasCycles) {
+ // Check for Cycles
+ hasCycles=checkReachable(tonode, rmwnode);
+ }
+
+ if (rmwnode->addEdge(tonode))
+ rollbackvector.push_back(rmwnode);
}
- fromnode->addEdge(tonode);
}
-/** Checks whether the first CycleNode can reach the second one. */
+/** Handles special case of a RMW action. 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. Only one RMW
+ * action can read from a given write.
+ */
+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)) {
+ hasRMWViolation=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.
+ */
+ std::vector<CycleNode *> * edges=fromnode->getEdges();
+ for(unsigned int i=0;i<edges->size();i++) {
+ CycleNode * tonode=(*edges)[i];
+ if (tonode!=rmwnode) {
+ if (rmwnode->addEdge(tonode))
+ rollbackvector.push_back(rmwnode);
+ }
+ }
+
+
+ if (!hasCycles) {
+ // With promises we could be setting up a cycle here if we aren't
+ // careful...avoid it..
+ hasCycles=checkReachable(rmwnode, fromnode);
+ }
+ if(fromnode->addEdge(rmwnode))
+ rollbackvector.push_back(fromnode);
+}
+
+#if SUPPORT_MOD_ORDER_DUMP
+void CycleGraph::dumpGraphToFile(const char *filename) {
+ char buffer[200];
+ sprintf(buffer, "%s.dot",filename);
+ FILE *file=fopen(buffer, "w");
+ fprintf(file, "digraph %s {\n",filename);
+ for(unsigned int i=0;i<nodeList.size();i++) {
+ CycleNode *cn=nodeList[i];
+ std::vector<CycleNode *> * edges=cn->getEdges();
+ 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());
+ for(unsigned int j=0;j<edges->size();j++) {
+ CycleNode *dst=(*edges)[j];
+ const ModelAction *dstaction=dst->getAction();
+ fprintf(file, "N%u -> N%u;\n", action->get_seq_number(), dstaction->get_seq_number());
+ }
+ }
+ fprintf(file,"}\n");
+ fclose(file);
+}
+#endif
+
+/**
+ * Checks whether one ModelAction can reach another.
+ * @param from The ModelAction from which to begin exploration
+ * @param to The ModelAction to reach
+ * @return True, @a from can reach @a to; otherwise, false
+ */
+bool CycleGraph::checkReachable(const ModelAction *from, const ModelAction *to) {
+ CycleNode *fromnode = actionToNode.get(from);
+ CycleNode *tonode = actionToNode.get(to);
+
+ if (!fromnode || !tonode)
+ return false;
+
+ return checkReachable(fromnode, tonode);
+}
+
+/**
+ * Checks whether one CycleNode can reach another.
+ * @param from The CycleNode from which to begin exploration
+ * @param to The CycleNode to reach
+ * @return True, @a from can reach @a to; otherwise, false
+ */
bool CycleGraph::checkReachable(CycleNode *from, CycleNode *to) {
- std::vector<CycleNode *> queue;
- HashTable<CycleNode *, CycleNode *, uintptr_t, 4> discovered;
+ std::vector<CycleNode *, MyAlloc<CycleNode *> > queue;
+ HashTable<CycleNode *, CycleNode *, uintptr_t, 4, MYMALLOC, MYCALLOC, MYFREE> discovered;
queue.push_back(from);
discovered.put(from, from);
return false;
}
-/** Returns whether a CycleGraph contains cycles. */
+void CycleGraph::startChanges() {
+ ASSERT(rollbackvector.size()==0);
+ ASSERT(rmwrollbackvector.size()==0);
+ ASSERT(oldCycles==hasCycles);
+ ASSERT(oldRMWViolation==hasRMWViolation);
+}
+
+/** Commit changes to the cyclegraph. */
+void CycleGraph::commitChanges() {
+ rollbackvector.resize(0);
+ rmwrollbackvector.resize(0);
+ oldCycles=hasCycles;
+ oldRMWViolation=hasRMWViolation;
+}
+
+/** Rollback changes to the previous commit. */
+void CycleGraph::rollbackChanges() {
+ for (unsigned int i = 0; i < rollbackvector.size(); i++) {
+ rollbackvector[i]->popEdge();
+ }
+
+ for (unsigned int i = 0; i < rmwrollbackvector.size(); i++) {
+ rmwrollbackvector[i]->clearRMW();
+ }
+
+ hasCycles = oldCycles;
+ hasRMWViolation = oldRMWViolation;
+ rollbackvector.resize(0);
+ rmwrollbackvector.resize(0);
+}
+
+/** @returns whether a CycleGraph contains cycles. */
bool CycleGraph::checkForCycles() {
return hasCycles;
}
-/** Constructor for a CycleNode. */
-
-CycleNode::CycleNode(ModelAction *modelaction) {
- action=modelaction;
+bool CycleGraph::checkForRMWViolation() {
+ return hasRMWViolation;
}
-/** Returns a vector of the edges from a CycleNode. */
+/**
+ * Constructor for a CycleNode.
+ * @param modelaction The ModelAction for this node
+ */
+CycleNode::CycleNode(const ModelAction *modelaction) :
+ action(modelaction),
+ hasRMW(NULL)
+{
+}
+/** @returns a vector of the edges from a CycleNode. */
std::vector<CycleNode *> * CycleNode::getEdges() {
return &edges;
}
-/** Adds an edge to a CycleNode. */
-
-void CycleNode::addEdge(CycleNode * node) {
+/**
+ * Adds an edge from this CycleNode to another CycleNode.
+ * @param node The node to which we add a directed edge
+ */
+bool CycleNode::addEdge(CycleNode *node) {
+ for(unsigned int i=0;i<edges.size();i++)
+ if (edges[i]==node)
+ return false;
edges.push_back(node);
+ return true;
+}
+
+/** @returns the RMW CycleNode that reads from the current CycleNode */
+CycleNode * CycleNode::getRMW() {
+ return hasRMW;
+}
+
+/**
+ * Set a RMW action node that reads from the current CycleNode.
+ * @param node The RMW that reads from the current node
+ * @return True, if this node already was read by another RMW; false otherwise
+ * @see CycleGraph::addRMWEdge
+ */
+bool CycleNode::setRMW(CycleNode *node) {
+ if (hasRMW!=NULL)
+ return true;
+ hasRMW=node;
+ return false;
}
projects / model-checker.git / blobdiff