/// <summary>
/// The function of each worker in swarm NDFS
/// </summary>
/// <returns></returns>
public void SwarmNestedDFSModelCheckingWorker()
{
Dictionary <string, List <string> > OutgoingTransitionTable = new Dictionary <string, List <string> >(Ultility.Ultility.MC_INITIAL_SIZE);
List <LocalPair> initials = LocalPair.GetInitialPairsLocal(BA, InitialStep);
if (initials.Count == 0)
{
VerificationOutput.VerificationResult = VerificationResultType.VALID;
return;
}
Stack <LocalPair> BlueStack = new Stack <LocalPair>(5000);
Dictionary <string, StateColor> colorData = new Dictionary <string, StateColor>(5000);
int threadId;
// Create random variable with different seed for each thread
Random rand; // helps different threads access different region of the graph
lock (MultiCoreLock)
{
threadId = MultiCoreSeed;
rand = new Random(MultiCoreSeed);
MultiCoreSeed++;
}
// Create the list of initial states
// May apply randomness here to increase performance
int[] permutation = generatePermutation(initials.Count, rand);
for (int z = 0; z < initials.Count; z++)
{
LocalPair initState = initials[permutation[z]];
BlueStack.Push(initState);
string ID = initState.GetCompressedState();
colorData.Add(ID, new StateColor());
OutgoingTransitionTable.Add(ID, new List <string>(8));
}
//store the expended event step of a node to avoid multiple invocation of the make one move.
Dictionary <string, List <LocalPair> > ExpendedNode = new Dictionary <string, List <LocalPair> >(1024);
do
{
if (CancelRequested || StopMutliCoreThreads)
{
return;
}
LocalPair pair = BlueStack.Peek();
ConfigurationBase evt = pair.configuration;
string BAState = pair.state;
string v = pair.GetCompressedState();
List <string> outgoing = OutgoingTransitionTable[v];
StateColor nodeColor = colorData[v];
if (nodeColor.IsWhite())
{
nodeColor.SetCyan();
}
bool blueDone = true;
// Initialize the node if first time visited
if (!ExpendedNode.ContainsKey(v))
{
//ConfigurationBase[] configList = evt.MakeOneMove().ToArray();
IEnumerable <ConfigurationBase> configList = evt.MakeOneMove();
pair.SetEnabled(configList, FairnessType);
List <LocalPair> product = LocalPair.NextLocal(BA, configList, BAState);
ExpendedNode.Add(v, product);
for (int k = product.Count - 1; k >= 0; k--)
{
LocalPair step = product[k];
string tmp = step.GetCompressedState();
//update the incoming and outgoing edges
outgoing.Add(tmp);
if (!colorData.ContainsKey(tmp))
{
colorData.Add(tmp, new StateColor());
OutgoingTransitionTable.Add(tmp, new List <string>(8));
}
}
}
List <LocalPair> list = ExpendedNode[v];
//transverse all neighbour nodes
for (int k = list.Count - 1; k >= 0; k--)
{
int randIndex = rand.Next(list.Count);
//int randIndex = list.Count - 1;
LocalPair step = list[randIndex];
string tmp = step.GetCompressedState();
StateColor neighbourColor = colorData[tmp];
//if the neighbour node is white
if (neighbourColor.IsWhite())
{
if (blueDone)
{
BlueStack.Push(step);
blueDone = false;
list.RemoveAt(randIndex);
break;
}
}
// if the neighbour node is cyan,
// and either this node or the neibour node is the accept state
// then report cycle
else if (neighbourColor.IsCyan())
{
if (step.state.EndsWith(Constants.ACCEPT_STATE) || pair.state.EndsWith(Constants.ACCEPT_STATE))
{
SwarmNestedDFSReportBlueCycle(step, pair, BlueStack, colorData, OutgoingTransitionTable);
return;
}
else
{
list.RemoveAt(randIndex);
}
}
// if the neighbour node is either blue or red,
// can remove from the list
else
{
list.RemoveAt(randIndex);
}
}
if (blueDone)
{
BlueStack.Pop();
// If the current node is an accept state,
// do the red DFS
if (pair.state.EndsWith(Constants.ACCEPT_STATE))
{
if (evt.IsDeadLock)
{
lock (MultiCoreLock)
{
StopMutliCoreThreads = true;
Dictionary <string, LocalPair> LoopPairs = new Dictionary <string, LocalPair>();
LoopPairs.Add(v, pair);
MultiCoreLocalTaskStack = BlueStack;
MultiCoreResultedLoop = LoopPairs;
MultiCoreOutgoingTransitionTable = OutgoingTransitionTable;
return;
}
}
bool stop = SwarmNestedDFSDepthFirstSearchRed(pair, BlueStack, OutgoingTransitionTable, colorData);
if (stop)
{
return;
}
nodeColor.SetRed();
}
else
{
nodeColor.SetBlue();
}
}
} while (BlueStack.Count > 0);
StopMutliCoreThreads = true;
VerificationOutput.VerificationResult = VerificationResultType.VALID;
VerificationOutput.NoOfStates = colorData.Count;
return;
}
/// <summary>
/// Run the verification using the Nested DFS algorithm and get the result.
/// Based on:
/// A Note on On-The-Fly Verification Algorithms
/// http://dl.acm.org/citation.cfm?id=2140670
/// Stefan Schwoon and Javier Esparza
/// Proceeding TACAS'05 Proceedings of the 11th international conference on
/// Tools and Algorithms for the Construction and Analysis of Systems
/// Springer-Verlag Berlin, Heidelberg, 2005
/// </summary>
/// <returns></returns>
public void NestedDFSModelChecking()
{
Dictionary <string, List <string> > OutgoingTransitionTable = new Dictionary <string, List <string> >(Ultility.Ultility.MC_INITIAL_SIZE);
VerificationOutput.CounterExampleTrace = null;
List <LocalPair> initials = LocalPair.GetInitialPairsLocal(BA, InitialStep);
if (initials.Count == 0)
{
VerificationOutput.VerificationResult = VerificationResultType.VALID;
return;
}
Stack <LocalPair> BlueStack = new Stack <LocalPair>(5000);
StringDictionary <StateColor> colorData = new StringDictionary <StateColor>(5000);
for (int z = 0; z < initials.Count; z++)
{
LocalPair initState = initials[z];
BlueStack.Push(initState);
string ID = initState.GetCompressedState();
colorData.Add(ID, new StateColor());
OutgoingTransitionTable.Add(ID, new List <string>(8));
}
//store the expended event step of a node to avoid multiple invocation of the make one move.
Dictionary <string, List <LocalPair> > ExpendedNode = new Dictionary <string, List <LocalPair> >(1024);
do
{
if (CancelRequested)
{
VerificationOutput.NoOfStates = colorData.Count; // VisitedWithID.Count;
return;
}
LocalPair pair = BlueStack.Peek();
ConfigurationBase evt = pair.configuration;
string BAState = pair.state;
string v = pair.GetCompressedState();
List <string> outgoing = OutgoingTransitionTable[v];
StateColor nodeColor = colorData.GetContainsKey(v);
if (nodeColor.IsWhite())
{
nodeColor.SetCyan();
}
bool blueDone = true;
if (ExpendedNode.ContainsKey(v))
{
List <LocalPair> list = ExpendedNode[v];
if (list.Count > 0)
{
//transverse all neighbour nodes
for (int k = list.Count - 1; k >= 0; k--)
{
LocalPair step = list[k];
string tmp = step.GetCompressedState();
StateColor neighbourColor = colorData.GetContainsKey(tmp);
//if the neighbour node is white
if (neighbourColor.IsWhite())
{
//only add the first unvisited node
//for the second or more unvisited steps, ignore at the monent
if (blueDone)
{
BlueStack.Push(step);
blueDone = false;
list.RemoveAt(k);
}
}
// if the neighbour node is cyan,
// and either this node or the neibour node is the accept state
// then report cycle
else if (neighbourColor.IsCyan())
{
if (step.state.EndsWith(Constants.ACCEPT_STATE) || pair.state.EndsWith(Constants.ACCEPT_STATE))
{
// Report cycle
ReportBlueCycle(step, pair, BlueStack, colorData, OutgoingTransitionTable);
return;
}
else
{
list.RemoveAt(k);
}
}
// if the neighbour node is either blue or red,
// can remove from the list
else
{
list.RemoveAt(k);
}
}
}
}
else
{
//ConfigurationBase[] list = evt.MakeOneMove().ToArray();
IEnumerable <ConfigurationBase> list = evt.MakeOneMove();
pair.SetEnabled(list, FairnessType);
List <LocalPair> product = LocalPair.NextLocal(BA, list, BAState);
//count the transitions visited
VerificationOutput.Transitions += product.Count;
for (int k = product.Count - 1; k >= 0; k--)
{
LocalPair step = product[k];
string tmp = step.GetCompressedState();
StateColor neighbourColor = colorData.GetContainsKey(tmp);
if (neighbourColor != null)
{
//update the incoming and outgoing edges
outgoing.Add(tmp);
//if this node is still not visited
if (neighbourColor.IsWhite())
{
//only add the first unvisited node
//for the second or more unvisited steps, ignore at the monent
if (blueDone)
{
BlueStack.Push(step);
blueDone = false;
product.RemoveAt(k);
}
}
// if the neighbour node is cyan,
// and either this node or the neibour node is the accept state
// then report cycle
else if (neighbourColor.IsCyan())
{
if (step.state.EndsWith(Constants.ACCEPT_STATE) || pair.state.EndsWith(Constants.ACCEPT_STATE))
{
// Report cycle
ReportBlueCycle(step, pair, BlueStack, colorData, OutgoingTransitionTable);
return;
}
else
{
product.RemoveAt(k);
}
}
// if the neighbour node is either blue or red,
// can remove from the list
else
{
product.RemoveAt(k);
}
}
// If the node is not initiated
else
{
colorData.Add(tmp, new StateColor());
OutgoingTransitionTable.Add(tmp, new List <string>(8));
outgoing.Add(tmp);
if (blueDone)
{
BlueStack.Push(step);
blueDone = false;
product.RemoveAt(k);
}
}
}
//create the remaining steps as the expending list for v
ExpendedNode.Add(v, product);
}
if (blueDone)
{
BlueStack.Pop();
// If the current node is an accept state,
// do the red DFS
if (pair.state.EndsWith(Constants.ACCEPT_STATE))
{
if (evt.IsDeadLock)
{
VerificationOutput.VerificationResult = VerificationResultType.INVALID;
VerificationOutput.NoOfStates = colorData.Count;
Dictionary <string, LocalPair> LoopPairs = new Dictionary <string, LocalPair>();
LoopPairs.Add(v, pair);
LocalTaskStack = BlueStack;
LocalGetCounterExample(LoopPairs, OutgoingTransitionTable);
return;
}
bool stop = DepthFirstSearchRed(pair, BlueStack, OutgoingTransitionTable, colorData);
if (stop)
{
return;
}
nodeColor.SetRed();
}
else
{
nodeColor.SetBlue();
}
}
} while (BlueStack.Count > 0);
VerificationOutput.VerificationResult = VerificationResultType.VALID;
VerificationOutput.NoOfStates = colorData.Count;
return;
}