#include "cyclegraph.h"
#include "action.h"
#include "common.h"
+#include "promise.h"
+#include "model.h"
/** Initializes a CycleGraph object. */
CycleGraph::CycleGraph() :
+ discovered(new HashTable<CycleNode *, CycleNode *, uintptr_t, 4, model_malloc, model_calloc, model_free>(16)),
hasCycles(false),
- oldCycles(false)
+ oldCycles(false),
+ hasRMWViolation(false),
+ oldRMWViolation(false)
{
}
/** CycleGraph destructor */
-CycleGraph::~CycleGraph() {
+CycleGraph::~CycleGraph()
+{
}
/**
* @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);
+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;
}
* @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) {
+void CycleGraph::addEdge(const ModelAction *from, const ModelAction *to)
+{
ASSERT(from);
ASSERT(to);
- CycleNode *fromnode=getNode(from);
- CycleNode *tonode=getNode(to);
+ CycleNode *fromnode = getNode(from);
+ CycleNode *tonode = getNode(to);
+ if (!hasCycles) {
+ // Reflexive edges are cycles
+ hasCycles = (from == to);
+ }
if (!hasCycles) {
// Check for Cycles
- hasCycles=checkReachable(tonode, fromnode);
+ hasCycles = checkReachable(tonode, fromnode);
}
- rollbackvector.push_back(fromnode);
- fromnode->addEdge(tonode);
+ 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
+ CycleNode *rmwnode = fromnode->getRMW();
- if (rmwnode!=NULL&&rmwnode!=tonode) {
+ /*
+ * 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);
+ hasCycles = checkReachable(tonode, rmwnode);
}
- rollbackvector.push_back(rmwnode);
- rmwnode->addEdge(tonode);
+
+ if (rmwnode->addEdge(tonode))
+ rollbackvector.push_back(rmwnode);
}
}
* 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) {
+void CycleGraph::addRMWEdge(const ModelAction *from, const ModelAction *rmw)
+{
ASSERT(from);
ASSERT(rmw);
- CycleNode *fromnode=getNode(from);
- CycleNode *rmwnode=getNode(rmw);
+ CycleNode *fromnode = getNode(from);
+ CycleNode *rmwnode = getNode(rmw);
/* Two RMW actions cannot read from the same write. */
if (fromnode->setRMW(rmwnode)) {
- hasCycles=true;
+ hasRMWViolation = true;
} else {
rmwrollbackvector.push_back(fromnode);
}
/* Transfer all outgoing edges from the from node to the rmw node */
- /* This process cannot add a cycle because rmw should not have any
- incoming edges yet.*/
- std::vector<CycleNode *> * edges=fromnode->getEdges();
- for(unsigned int i=0;i<edges->size();i++) {
- CycleNode * tonode=(*edges)[i];
- rollbackvector.push_back(rmwnode);
- rmwnode->addEdge(tonode);
+ /* 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);
+ }
+ }
+
+
+ if (!hasCycles) {
+ // Reflexive edges are cycles
+ hasCycles = (from == rmw);
+ }
+ if (!hasCycles) {
+ // With promises we could be setting up a cycle here if we aren't
+ // careful...avoid it..
+ hasCycles = checkReachable(rmwnode, fromnode);
}
- rollbackvector.push_back(fromnode);
- fromnode->addEdge(rmwnode);
+ if (fromnode->addEdge(rmwnode))
+ rollbackvector.push_back(fromnode);
}
+#if SUPPORT_MOD_ORDER_DUMP
+void CycleGraph::dumpNodes(FILE *file)
+{
+ 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)
+{
+ 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.
* @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) {
+bool CycleGraph::checkReachable(const ModelAction *from, const ModelAction *to)
+{
CycleNode *fromnode = actionToNode.get(from);
CycleNode *tonode = actionToNode.get(to);
* @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;
+bool CycleGraph::checkReachable(CycleNode *from, CycleNode *to)
+{
+ std::vector<CycleNode *, ModelAlloc<CycleNode *> > queue;
+ discovered->reset();
queue.push_back(from);
- discovered.put(from, from);
- while(!queue.empty()) {
- CycleNode * node=queue.back();
+ discovered->put(from, from);
+ while (!queue.empty()) {
+ CycleNode *node = queue.back();
queue.pop_back();
- if (node==to)
+ if (node == to)
return true;
- for(unsigned int i=0;i<node->getEdges()->size();i++) {
- CycleNode *next=(*node->getEdges())[i];
- if (!discovered.contains(next)) {
- discovered.put(next,next);
+ for (unsigned int i = 0; i < node->getNumEdges(); i++) {
+ CycleNode *next = node->getEdge(i);
+ if (!discovered->contains(next)) {
+ discovered->put(next,next);
queue.push_back(next);
}
}
return false;
}
-void CycleGraph::startChanges() {
- ASSERT(rollbackvector.size()==0);
- ASSERT(rmwrollbackvector.size()==0);
- ASSERT(oldCycles==hasCycles);
+bool CycleGraph::checkPromise(const ModelAction *fromact, Promise *promise)
+{
+ std::vector<CycleNode *, ModelAlloc<CycleNode *> > queue;
+ discovered->reset();
+ CycleNode *from = actionToNode.get(fromact);
+
+ queue.push_back(from);
+ discovered->put(from, from);
+ while (!queue.empty()) {
+ CycleNode *node = queue.back();
+ queue.pop_back();
+
+ if (promise->increment_threads(node->getAction()->get_tid())) {
+ return true;
+ }
+
+ for (unsigned int i = 0; i < node->getNumEdges(); i++) {
+ CycleNode *next = node->getEdge(i);
+ if (!discovered->contains(next)) {
+ discovered->put(next,next);
+ queue.push_back(next);
+ }
+ }
+ }
+ return false;
+}
+
+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() {
+void CycleGraph::commitChanges()
+{
rollbackvector.resize(0);
rmwrollbackvector.resize(0);
- oldCycles=hasCycles;
+ oldCycles = hasCycles;
+ oldRMWViolation = hasRMWViolation;
}
/** Rollback changes to the previous commit. */
}
hasCycles = oldCycles;
+ hasRMWViolation = oldRMWViolation;
rollbackvector.resize(0);
rmwrollbackvector.resize(0);
}
return hasCycles;
}
+bool CycleGraph::checkForRMWViolation() {
+ return hasRMWViolation;
+}
+
/**
* Constructor for a CycleNode.
* @param modelaction The ModelAction for this node
{
}
-/** @returns a vector of the edges from a CycleNode. */
-std::vector<CycleNode *> * CycleNode::getEdges() {
- return &edges;
+/**
+ * @param i The index of the edge to return
+ * @returns The a CycleNode edge indexed by i
+ */
+CycleNode * CycleNode::getEdge(unsigned int i) const
+{
+ return edges[i];
+}
+
+/** @returns The number of edges leaving this CycleNode */
+unsigned int CycleNode::getNumEdges() const
+{
+ return edges.size();
}
/**
* Adds an edge from this CycleNode to another CycleNode.
* @param node The node to which we add a directed edge
*/
-void CycleNode::addEdge(CycleNode *node) {
+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() {
+CycleNode * CycleNode::getRMW() const
+{
return hasRMW;
}
* @return True, if this node already was read by another RMW; false otherwise
* @see CycleGraph::addRMWEdge
*/
-bool CycleNode::setRMW(CycleNode *node) {
- if (hasRMW!=NULL)
+bool CycleNode::setRMW(CycleNode *node)
+{
+ if (hasRMW != NULL)
return true;
- hasRMW=node;
+ hasRMW = node;
return false;
}