private void BuildTransferFunctions()
{
foreach (CFGNode node in ProgramCFG.CfgNodes)
{
if (node is CFGNodeStatement)
{
if ((node is CFGNodeStmtSkip) || (node is CFGNodeStmtPrint) ||
(node is CFGNodeStmtGoto) || (node is CFGNodeStmtReturn))
{
(node as CFGNodeStatement).Transfer = HelperFunctions.BuildIdentityTransfer(m_BddManager,
(node as CFGNodeStatement).ProcOf.LocalVariables.VariablesToId,
ProgramCFG.GlobalVariables.VariablesToId);
}
else
if (node is CFGNodeStmtAssignment)
{
(node as CFGNodeStmtAssignment).Transfer =
CFGNodeStmtAssignment.BuildAssignmentTransfer(node.GetAST(), m_BddManager,
(node as CFGNodeStatement).ProcOf.LocalVariables.VariablesToId,
ProgramCFG.GlobalVariables.VariablesToId);
}
else
if (node is CFGNodeStmtConditional)
{
Bdd TransferTrue, TransferFalse;
CommonAST decider = node.GetAST().getFirstChild() as CommonAST;
HelperFunctions.BuildDeciderTransfers(decider, m_BddManager,
(node as CFGNodeStatement).ProcOf.LocalVariables.VariablesToId,
ProgramCFG.GlobalVariables.VariablesToId, out TransferTrue, out TransferFalse);
(node as CFGNodeStmtConditional).TransferTrue = TransferTrue;
(node as CFGNodeStmtConditional).TransferFalse = TransferFalse;
}
else
if (node is CFGNodeStmtProcCall)
{
CFGNodeProcedure procedureCalled;
if (!(ProgramCFG.ProcedureNameToNode().TryGetValue(
node.GetAST().getFirstChild().getText(), out procedureCalled)))
{
System.Diagnostics.Debug.Assert(false);
}
(node as CFGNodeStmtProcCall).Transfer =
CFGNodeStmtProcCall.buildProcCallTransfer(node.GetAST(), procedureCalled, m_BddManager,
(node as CFGNodeStatement).ProcOf.LocalVariables.VariablesToId,
ProgramCFG.GlobalVariables.VariablesToId);
}
}
}
}
public Trajectory BuildTrajectory(CFGNode node)
{
int len, i;
Trajectory tempTrajectory = new Trajectory();
PathEdges paths, predecessorPaths;
PathEdgesPartition pathPart;
Bdd pathBdd = null;
m_PathEdges.TryGetValue(node, out paths);
if (paths.PathEdgesByLength.Count != 0)
{
pathPart = paths.PathEdgesByLength[0];
len = pathPart.Length;
pathBdd = BuildRandomPath(pathPart.PathEdges);
while (len > 0)
{
tempTrajectory.Add(new TrajectoryItem(node, pathBdd));
#region Node is not first statement of procedure
if ((node is CFGNodeProcedure) || ((node is CFGNodeStatement) && (node as CFGNodeStatement).ProcOf.FirstStmtOf != node))
{
Bdd tempPathEdges, reverseJoin, bddOK;
if (((node is CFGNodeStmtSkip) && (node as CFGNodeStmtSkip).previousProcCall != null))
{
CFGNodeStmtProcCall nodePredecessor = (node as CFGNodeStmtSkip).previousProcCall;
Bdd[] bddArray = new Bdd[nodePredecessor.ProcOf.LocalVariables.Length * 4 + ProgramCFG.GlobalVariables.Length * 4];
Bdd summaryEdges, summaryEdgesReverse;
m_PathEdges.TryGetValue(nodePredecessor as CFGNode, out predecessorPaths);
m_SummaryEdges.TryGetValue(nodePredecessor as CFGNode, out summaryEdges);
tempPathEdges = predecessorPaths.GetPathEdgesOfLength(len - 1);
if (tempPathEdges != null)
{
i = -1;
foreach (int id in nodePredecessor.ProcOf.LocalVariables.VariablesToId.Values)
{
bddArray[++i] = m_BddManager.GetBddVariableWithID(id);
bddArray[++i] = m_BddManager.GetBddVariableWithID(id + 2);
bddArray[++i] = m_BddManager.GetBddVariableWithID(id + 2);
bddArray[++i] = m_BddManager.GetBddVariableWithID(id);
}
foreach (int id in ProgramCFG.GlobalVariables.VariablesToId.Values)
{
bddArray[++i] = m_BddManager.GetBddVariableWithID(id);
bddArray[++i] = m_BddManager.GetBddVariableWithID(id + 2);
bddArray[++i] = m_BddManager.GetBddVariableWithID(id + 2);
bddArray[++i] = m_BddManager.GetBddVariableWithID(id);
}
summaryEdgesReverse = summaryEdges.Replace(bddArray);
reverseJoin = Join(pathBdd, summaryEdgesReverse, nodePredecessor.ProcOf.LocalVariables);
summaryEdgesReverse.FreeBdd();
bddOK = m_BddManager.LogicalAnd(reverseJoin, tempPathEdges);
reverseJoin.FreeBdd();
pathBdd = BuildRandomPath(bddOK);
bddOK.FreeBdd();
node = nodePredecessor as CFGNode;
len--;
}
}
else
{
foreach (CFGNode tempNode in node.Predecessor)
{
CFGNodeStatement nodePredecessor = tempNode as CFGNodeStatement;
Bdd[] bddArray = new Bdd[nodePredecessor.ProcOf.LocalVariables.Length * 4 + ProgramCFG.GlobalVariables.Length * 4];
Bdd transferReverse;
m_PathEdges.TryGetValue(tempNode, out predecessorPaths);
tempPathEdges = predecessorPaths.GetPathEdgesOfLength(len - 1);
if (tempPathEdges != null)
{
i = -1;
foreach (int id in nodePredecessor.ProcOf.LocalVariables.VariablesToId.Values)
{
bddArray[++i] = m_BddManager.GetBddVariableWithID(id);
bddArray[++i] = m_BddManager.GetBddVariableWithID(id + 2);
bddArray[++i] = m_BddManager.GetBddVariableWithID(id + 2);
bddArray[++i] = m_BddManager.GetBddVariableWithID(id);
}
foreach (int id in ProgramCFG.GlobalVariables.VariablesToId.Values)
{
bddArray[++i] = m_BddManager.GetBddVariableWithID(id);
bddArray[++i] = m_BddManager.GetBddVariableWithID(id + 2);
bddArray[++i] = m_BddManager.GetBddVariableWithID(id + 2);
bddArray[++i] = m_BddManager.GetBddVariableWithID(id);
}
if (nodePredecessor is CFGNodeStmtConditional)
{
if ((nodePredecessor as CFGNodeStmtConditional).TrueSuccesor == node)
{
transferReverse = (nodePredecessor as CFGNodeStmtConditional).TransferTrue.Replace(bddArray);
reverseJoin = Join(pathBdd, transferReverse, nodePredecessor.ProcOf.LocalVariables);
transferReverse.FreeBdd();
}
else
{
transferReverse = (nodePredecessor as CFGNodeStmtConditional).TransferFalse.Replace(bddArray);
reverseJoin = Join(pathBdd, transferReverse, nodePredecessor.ProcOf.LocalVariables);
transferReverse.FreeBdd();
}
}
else
{
transferReverse = nodePredecessor.Transfer.Replace(bddArray);
reverseJoin = Join(pathBdd, transferReverse, nodePredecessor.ProcOf.LocalVariables);
transferReverse.FreeBdd();
}
bddOK = m_BddManager.LogicalAnd(reverseJoin, tempPathEdges);
if (bddOK.ReturnBddType() != BddType.Zero)
{
pathBdd = BuildRandomPath(bddOK);
bddOK.FreeBdd();
node = tempNode;
len--;
break;
}
else
{
bddOK.FreeBdd();
}
}
}
}
}
#endregion
#region Node is first statement of procedure
else
{
Bdd[] bddArray = new Bdd[(node as CFGNodeStatement).ProcOf.LocalVariables.Length + ProgramCFG.GlobalVariables.Length];
Bdd[] bddArrayForTransfer = new Bdd[(node as CFGNodeStatement).ProcOf.LocalVariables.Length + ProgramCFG.GlobalVariables.Length];
Bdd bddExist, tempPathEdges, bddAndWithTransfer, bddAndWithProcCall, bddExistTransfer, bddReplaceTransfer;
i = -1;
foreach (int id in (node as CFGNodeStatement).ProcOf.LocalVariables.VariablesToId.Values)
{
bddArray[++i] = m_BddManager.GetBddVariableWithID(id);
bddArrayForTransfer[i] = m_BddManager.GetBddVariableWithID(id + 2);
}
foreach (int id in ProgramCFG.GlobalVariables.VariablesToId.Values)
{
bddArray[++i] = m_BddManager.GetBddVariableWithID(id);
bddArrayForTransfer[i] = m_BddManager.GetBddVariableWithID(id + 2);
}
bddExist = pathBdd.Exists(bddArray);
foreach (CFGNodeStmtProcCall nodePredecessor in node.Predecessor)
{
m_PathEdges.TryGetValue(nodePredecessor, out predecessorPaths);
tempPathEdges = predecessorPaths.GetPathEdgesOfLength(len - 1);
Bdd[] bddArrayReplace = new Bdd[nodePredecessor.ProcOf.LocalVariables.Length * 2 + ProgramCFG.GlobalVariables.Length * 2];
if (tempPathEdges != null)
{
bddAndWithTransfer = m_BddManager.LogicalAnd(nodePredecessor.Transfer, bddExist);
bddExistTransfer = bddAndWithTransfer.Exists(bddArrayForTransfer);
bddAndWithTransfer.FreeBdd();
i = -1;
foreach (int id in nodePredecessor.ProcOf.LocalVariables.VariablesToId.Values)
{
bddArrayReplace[++i] = m_BddManager.GetBddVariableWithID(id);
bddArrayReplace[++i] = m_BddManager.GetBddVariableWithID(id + 2);
}
foreach (int id in ProgramCFG.GlobalVariables.VariablesToId.Values)
{
bddArrayReplace[++i] = m_BddManager.GetBddVariableWithID(id);
bddArrayReplace[++i] = m_BddManager.GetBddVariableWithID(id + 2);
}
bddReplaceTransfer = bddExistTransfer.Replace(bddArrayReplace);
bddExistTransfer.FreeBdd();
bddAndWithProcCall = m_BddManager.LogicalAnd(bddReplaceTransfer, tempPathEdges);
bddReplaceTransfer.FreeBdd();
if (bddAndWithProcCall.GetBddRootVariable().ReturnBddType() != BddType.Zero)
{
pathBdd = BuildRandomPath(bddAndWithProcCall);
bddAndWithProcCall.FreeBdd();
node = nodePredecessor as CFGNode;
len--;
break;
}
else
{
bddAndWithProcCall.FreeBdd();
}
}
}
}
#endregion
}
}
tempTrajectory.Add(new TrajectoryItem(node, pathBdd));
tempTrajectory.TrajectoryList.Reverse();
return(tempTrajectory);
}
private Bdd Lift(CFGNodeStmtProcCall procCallNode, CFGNodeProcedure exitNode)
{
int i = 0;
int id;
Bdd[] bddArrayFormalsNot = new Bdd[2 * exitNode.LocalVariables.Length - exitNode.FormalParameters.Length];
//Bdd[] bddArrayFormals = new Bdd[2 * exitNode.FormalParameters.Length];
Bdd[] bddArrayForSubstitution = new Bdd[2 * exitNode.FormalParameters.Length];
Bdd tempBdd, tempBddAnd, tempBddXnor, tempBddReplace;
Bdd var, exp, identity;
CommonAST walkerVar = exitNode.GetAST().getFirstChild() as CommonAST;
CommonAST walkerExp = procCallNode.GetAST().getFirstChild().getFirstChild() as CommonAST;
foreach (string varName in exitNode.LocalVariables.VariablesToId.Keys)
{
exitNode.LocalVariables.VariablesToId.TryGetValue(varName, out id);
if (exitNode.FormalParameters.VariablesToId.ContainsKey(varName) == false)
{
bddArrayFormalsNot[i++] = m_BddManager.GetBddVariableWithID(id);
bddArrayFormalsNot[i++] = m_BddManager.GetBddVariableWithID(id + 2);
}
else
{
bddArrayFormalsNot[i++] = m_BddManager.GetBddVariableWithID(id + 2);
}
}
PathEdges tempPath;
m_PathEdges.TryGetValue(exitNode, out tempPath);
tempBdd = tempPath.GetJointPaths(m_BddManager);
tempBdd = tempBdd.Exists(bddArrayFormalsNot);
i = 0;
while (walkerVar.Type == BoolParserTokenTypes.ID)
{
exitNode.LocalVariables.VariablesToId.TryGetValue(walkerVar.getText(), out id);
exp = HelperFunctions.ExprToBdd(walkerExp, m_BddManager, procCallNode.ProcOf.LocalVariables.VariablesToId, ProgramCFG.GlobalVariables.VariablesToId);
var = m_BddManager.GetBddVariableWithID(id);
bddArrayForSubstitution[i++] = var;
bddArrayForSubstitution[i++] = exp;
/*
* tempBddXnor = m_BddManager.LogicalXnor(exp, var);
* tempBddAnd = m_BddManager.LogicalAnd(tempBddXnor, tempBdd);
*
* tempBdd.FreeBdd();
* exp.FreeBdd();
* tempBdd = tempBddAnd;
*/
walkerExp = walkerExp.getNextSibling() as CommonAST;
walkerVar = walkerVar.getNextSibling() as CommonAST;
}
i = 0;
/*
* foreach (int bddId in exitNode.FormalParameters.VariablesToId.Values)
* {
* bddArrayFormals[i++] = m_BddManager.GetBddVariableWithID(bddId);
* bddArrayFormals[i++] = m_BddManager.GetBddVariableWithID(bddId + 2);
* }*/
tempBddReplace = tempBdd.Replace(bddArrayForSubstitution);
tempBdd.FreeBdd();
tempBdd = tempBddReplace;
identity = HelperFunctions.BuildIdentityTransfer(m_BddManager, procCallNode.ProcOf.LocalVariables.VariablesToId, null);
tempBddAnd = m_BddManager.LogicalAnd(tempBdd, identity);
tempBdd.FreeBdd();
identity.FreeBdd();
tempBdd = tempBddAnd;
return(tempBdd);
}
public void Reachable(debugPrintDelegate debugPrint)
{
if (ProgramCFG.CfgNodes.Count <= 1)
{
debugPrint("Invalid Program, unable to proceed!\n");
return;
}
m_PathEdges.Clear();
m_SummaryEdges.Clear();
BuildTransferFunctions();
LinkedList <CFGNode> workList = new LinkedList <CFGNode>();
CFGNodeProcedure tempNodeProc;
CFGNode tempNode;
Bdd bddLift, bddSummaryEdges, bddNew;
PathEdges bddSelfLoop, bddJoin, bddPathEdges;
Bdd [] array = new Bdd[3];
foreach (CFGNode node in ProgramCFG.CfgNodes)
{
m_PathEdges.Add(node, new PathEdges());
m_SummaryEdges.Add(node, m_BddManager.CreateBddZero());
}
ProgramCFG.ProcedureNameToNode().TryGetValue("main", out tempNodeProc);
workList.AddFirst(tempNodeProc.FirstStmtOf);
m_PathEdges.Remove(tempNodeProc.FirstStmtOf);
PathEdges firstMain = new PathEdges();
firstMain.AddPathEdge(new PathEdgesPartition(0, HelperFunctions.BuildIdentityTransfer
(m_BddManager, tempNodeProc.LocalVariables.VariablesToId, ProgramCFG.GlobalVariables.VariablesToId)), m_BddManager);
m_PathEdges.Add(tempNodeProc.FirstStmtOf, firstMain);
#region Debug part of the reachability algorithm
/*
* ///////Debug ////////////
* Dictionary<string, int>.ValueCollection valCollection = tempNodeProc.LocalVariables.VariablesToId.Values;
* foreach (int id in valCollection)
* {
* tempBdd1 = tempBdd;
* tempBdd = m_BddManager.LogicalOr(tempBdd, m_BddManager.GetBddVariableWithID(id));
* tempBdd1.FreeBdd();
* tempBdd1 = tempBdd;
* tempBdd = m_BddManager.LogicalXnor(tempBdd, m_BddManager.GetBddVariableWithID(id + 2));
* tempBdd1.FreeBdd();
* }
*
* foreach (int id in ProgramCFG.GlobalVariables.VariablesToId.Values)
* {
* tempBdd1 = tempBdd;
* tempBdd = m_BddManager.LogicalImplies(tempBdd, m_BddManager.GetBddVariableWithID(id));
* tempBdd1.FreeBdd();
* tempBdd1 = tempBdd;
* tempBdd = m_BddManager.LogicalOr(tempBdd, m_BddManager.GetBddVariableWithID(id + 2));
* tempBdd1.FreeBdd();
* }
* array[0] = tempBdd;
* tempBdd = m_BddManager.CreateBddOne();
*
* foreach (int id in valCollection)
* {
* tempBdd1 = tempBdd;
* tempBdd = m_BddManager.LogicalAnd(tempBdd, m_BddManager.GetBddVariableWithID(id));
* tempBdd1.FreeBdd();
* tempBdd1 = tempBdd;
* tempBdd = m_BddManager.LogicalNor(tempBdd, m_BddManager.GetBddVariableWithID(id + 2));
* tempBdd1.FreeBdd();
* }
*
* foreach (int id in ProgramCFG.GlobalVariables.VariablesToId.Values)
* {
* tempBdd1 = tempBdd;
* tempBdd = m_BddManager.LogicalImplies(tempBdd, m_BddManager.GetBddVariableWithID(id));
* tempBdd1.FreeBdd();
* tempBdd1 = tempBdd;
* tempBdd = m_BddManager.LogicalXor(tempBdd, m_BddManager.GetBddVariableWithID(id + 2));
* tempBdd1.FreeBdd();
* }
* array[1] = tempBdd;
*
* //array[2] = Join(array[0], array[1], tempNodeProc.LocalVariables);
* array[2] = SelfLoop(array[1], tempNodeProc.LocalVariables, tempNodeProc.LocalVariables);
* m_BddManager.ForceGarbageCollection();
* return array;
* ////////////////////////
*/
#endregion
while (workList.Count != 0)
{
tempNode = workList.First.Value;
debugPrint("Processing Node: " + tempNode.ToString() + ".\n");
workList.RemoveFirst();
if (tempNode is CFGNodeStmtProcCall)
{
CFGNodeStmtProcCall procCall = tempNode as CFGNodeStmtProcCall;
m_PathEdges.TryGetValue(tempNode, out bddPathEdges);
bddJoin = Join(bddPathEdges, procCall.Transfer, procCall.ProcOf.LocalVariables);
bddSelfLoop = SelfLoop(bddJoin, procCall.ProcOf.LocalVariables, (procCall.Succesor as CFGNodeStatement).ProcOf.LocalVariables);
Propagate(procCall.Succesor, bddSelfLoop, workList);
bddJoin.FreeAllBdd();
bddSelfLoop.FreeAllBdd();
m_PathEdges.TryGetValue(tempNode, out bddPathEdges);
m_SummaryEdges.TryGetValue(tempNode, out bddSummaryEdges);
if (bddSummaryEdges != null)
{
bddJoin = Join(bddPathEdges, bddSummaryEdges, procCall.ProcOf.LocalVariables);
Propagate(procCall.ReturnPoint, bddJoin, workList);
bddJoin.FreeAllBdd();
}
}
else if (tempNode is CFGNodeProcedure)
{
foreach (CFGNodeStmtSkip node in (tempNode as CFGNodeProcedure).Succesor)
{
bddLift = Lift(node.previousProcCall, tempNode as CFGNodeProcedure);
m_SummaryEdges.TryGetValue(node.previousProcCall, out bddSummaryEdges);
m_PathEdges.TryGetValue(node.previousProcCall, out bddPathEdges);
if (bddSummaryEdges != null)
{
bddNew = m_BddManager.LogicalOr(bddLift, bddSummaryEdges);
bddLift.FreeBdd();
}
else
{
bddNew = bddLift;
}
if (bddSummaryEdges != bddNew)
{
m_SummaryEdges.Remove(node.previousProcCall);
m_SummaryEdges.Add(node.previousProcCall, bddNew);
bddSummaryEdges.FreeBdd();
bddJoin = Join(bddPathEdges, bddNew, (node as CFGNodeStmtSkip).previousProcCall.ProcOf.LocalVariables);
Propagate(node, bddJoin, workList);
bddJoin.FreeAllBdd();
}
}
}
else if (tempNode is CFGNodeStmtConditional)
{
CFGNodeStmtConditional tempNode1 = tempNode as CFGNodeStmtConditional;
m_PathEdges.TryGetValue(tempNode, out bddPathEdges);
bddJoin = Join(bddPathEdges, tempNode1.TransferTrue, tempNode1.ProcOf.LocalVariables);
Propagate(tempNode1.TrueSuccesor, bddJoin, workList);
bddJoin.FreeAllBdd();
m_PathEdges.TryGetValue(tempNode, out bddPathEdges);
bddJoin = Join(bddPathEdges, tempNode1.TransferFalse, tempNode1.ProcOf.LocalVariables);
Propagate(tempNode1.FalseSuccesor, bddJoin, workList);
bddJoin.FreeAllBdd();
}
else
{
if (!(tempNode is CFGNodeError))
{
m_PathEdges.TryGetValue(tempNode, out bddPathEdges);
bddJoin = Join(bddPathEdges, (tempNode as CFGNodeStatement).Transfer, (tempNode as CFGNodeStatement).ProcOf.LocalVariables);
Propagate(tempNode.Succesor, bddJoin, workList);
bddJoin.FreeAllBdd();
}
}
}
m_BddManager.ForceGarbageCollection();
}
