// Finds back path from source to target, true if it is.
public bool FindBackwardPath(CFGNode source, CFGNode target)
{
List <Edge <CFGNode> > incoming_edges = null;
if (Tree.ContainsVertex(source) && !Tree.IsInEdgesEmpty(source))
{
incoming_edges = Tree.InEdges(source).ToList();
}
else
{
return(false);
}
while (incoming_edges.Count() > 0)
{
var edge = incoming_edges.First();
if (edge.Source.Equals(target))
{
return(true);
}
else
{
incoming_edges = Tree.InEdges(edge.Source).ToList();
}
}
return(false);
}
private void AcceptChild(CFGNode child)
{
if (child.ParentsNodes.Contains(this))
{
return;
}
child.ParentsNodes.Add(this);
}
public bool MoveBack()
{
if (_path.Count == 0)
{
return(false);
}
_current = _path.Pop();
return(true);
}
public List <CFGNode> findBetween(CFGNode from, CFGNode to)
{
visitedNodes = new List <CFGNode>();
visitedNodes.Add(to);
backDFS(from);
return(visitedNodes);
}
// Constructor from list of blocks
public CFGraph(List <IBaseBlock> blocks)
{
Blocks = blocks;
EdgeTypes = new EdgeTypes();
// First step - construct
List <CFGNode> cfg_nodes = new List <CFGNode>(blocks.Count);
for (int i = 0; i < blocks.Count; i++)
{
cfg_nodes.Add(new CFGNode(blocks[i]));
}
// Second step - make connections
for (int i = 0; i < cfg_nodes.Count; i++)
{
var lastOp = cfg_nodes[i].Value.Enumerate().Last();
if (i != cfg_nodes.Count - 1 &&
lastOp.Operation != LinearRepr.Values.Operation.Goto)
{
cfg_nodes[i].SetDirectChild(cfg_nodes[i + 1]);
}
if (lastOp.Operation == LinearRepr.Values.Operation.Goto ||
lastOp.Operation == LinearRepr.Values.Operation.CondGoto)
{
var gotoBlock = blocks.FirstOrDefault(b => b.Enumerate().First().Label.Equals(lastOp.Destination));
CFGNode goto_node = cfg_nodes.Find(el => el.Value == gotoBlock);
cfg_nodes[i].SetGotoChild(goto_node);
}
}
// Make IList and add as vertexes
var base_cfg_nodes = cfg_nodes as IList <CFGNode> ?? cfg_nodes.ToList();
graph.AddVertexRange(base_cfg_nodes);
// Add edges now
foreach (var node in base_cfg_nodes)
{
if (node.directChild != null)
{
graph.AddEdge(new Edge <CFGNode>(node, node.directChild));
}
if (node.gotoNode != null)
{
graph.AddEdge(new Edge <CFGNode>(node, node.gotoNode));
}
}
ClassificateEdges();
buildDominatorTree();
naturalCycleGraph = new NaturalCycleGraph(this);
}
private CFGNode Move(CFGNode next)
{
if (next == null)
{
return(null);
}
_path.Push(_current);
return(_current = next);
}
private void backDFS(CFGNode currentNode)
{
if (!visitedNodes.Contains(currentNode))
{
visitedNodes.Add(currentNode);
}
getNodes(currentNode).ToList()
.Where(node => !visitedNodes.Contains(node)).ToList()
.ForEach(node => backDFS(node));
}
// Build tree
private void BuildTree(CFGNode node, ref int currentNumber)
{
if (node == null)
{
return;
}
visited.Add(node);
Numbers[node] = currentNumber;
if (node.directChild == null && node.gotoNode == null)
{
return;
}
var children = new List <CFGNode>();
if (node.directChild != null)
{
children.Add(node.directChild);
}
if (node.gotoNode != null)
{
children.Add(node.gotoNode);
}
if (!Tree.Vertices.Contains(node))
{
Tree.AddVertex(node);
}
foreach (var child in children)
{
if (!visited.Contains(child))
{
if (!Tree.Vertices.Contains(child))
{
Tree.AddVertex(child);
}
Tree.AddEdge(new Edge <CFGNode>(node, child));
currentNumber += 1;
//Console.WriteLine(currentNumber);
BuildTree(child, ref currentNumber);
}
}
}
public CFGraph(List <IBaseBlock> blocks)
{
this.Blocks = blocks;
List <CFGNode> cfg_nodes = new List <CFGNode>(blocks.Count);
for (int i = 0; i < blocks.Count; i++)
{
cfg_nodes.Add(new CFGNode(blocks[i]));
}
for (int i = 0; i < cfg_nodes.Count; i++)
{
if (i != cfg_nodes.Count - 1)
{
cfg_nodes[i].SetDirectChild(cfg_nodes[i + 1]);
}
var lastOp = cfg_nodes[i].Value.Enumerate().Last();
if (lastOp.Operation == LinearRepr.Values.Operation.Goto)
{
var gotoBlock = blocks.First(b => b.Enumerate().First().Label.Equals(lastOp.Destination));
CFGNode goto_node = cfg_nodes.Find(el => el.Value == gotoBlock);
cfg_nodes[i].SetGotoChild(goto_node);
}
}
var base_cfg_nodes = cfg_nodes as IList <CFGNode> ?? cfg_nodes.ToList();
graph.AddVertexRange(base_cfg_nodes);
foreach (var node in base_cfg_nodes)
{
if (node.directChild != null)
{
graph.AddEdge(new Edge <CFGNode>(node, node.directChild));
}
if (node.gotoNode != null)
{
graph.AddEdge(new Edge <CFGNode>(node, node.gotoNode));
}
}
}
public static CFGraph Build(List <IBaseBlock> blocks)
{
CFGNode root = new CFGNode(blocks.First());
var currentNode = root;
foreach (var block in blocks.Skip(1))
{
var directChild = new CFGNode(block);
currentNode.SetDirectChild(directChild);
var lastOp = currentNode.Value.Enumerate().Last();
if (lastOp.IsGoto())
{
var gotoBlock = blocks.First(b => b.Enumerate().First().Label.Equals(lastOp.Destination));
var gotoChild = new CFGNode(gotoBlock);
currentNode.SetGotoChild(gotoChild);
}
currentNode = directChild;
}
var graph = new CFGraph(blocks);
return(graph);
}
public void Reset()
{
_current = _root;
_path.Clear();
}
public CFGLookup(CFGNode root)
{
_root = root;
_current = root;
}
private int getNodeIndex(CFGNode node)
{
return(graph.Vertices.ToList().IndexOf(node));
}
public void SetGotoChild(CFGNode child)
{
gotoNode = child;
AcceptChild(child);
}
public void SetDirectChild(CFGNode child)
{
directChild = child;
AcceptChild(child);
}
private IEnumerable <CFGNode> getNodes(CFGNode node)
{
return(cfGraph.graph.Edges
.Where(edge => edge.Target == node)
.Select(edge => edge.Source));
}
private bool isDominate(CFGNode from, CFGNode to)
{
return(dominatorTree.isDominate(from, to));
}