/// <summary>
/// A constructor that recives the code of the basic block
/// </summary>
/// <param name="basicBlockCode">The Code in the new basic block</param>
public GraphNode(String basicBlockCode)
{
branch1 = null;
branch2 = null;
this.basicBlockCode = basicBlockCode;
}
/// <summary>
/// This method removes a dominatee to my dominated nodes list
/// </summary>
/// <param name="dominatedNodeKey">The key of the dominated node</param>
/// <param name="dominatedNode">The dominated node</param>
private void RemoveFromDominated(String dominatedNodeKey, GraphNode dominatedNode)
{
if (this.DominatedList.ContainsKey(dominatedNodeKey)) //if node is in the list
{
DominatedList.Remove(dominatedNodeKey);
}
}
/// <summary>
/// Empty Constructor
/// </summary>
public GraphNode()
{
branch1 = null;
branch2 = null;
this.basicBlockCode = "";
}
/// <summary>
/// This method adds a dominatee to my dominated nodes list
/// </summary>
/// <param name="dominatedNodeKey">The key of the dominated node</param>
/// <param name="dominatedNode">The dominated node</param>
private void addToDominated(String dominatedNodeKey,GraphNode dominatedNode)
{
if (!this.DominatedList.ContainsKey(dominatedNodeKey)) //if node not allready in list
{
DominatedList.Add(dominatedNodeKey, dominatedNode);
}
}
/////////////////////////////////////////////////////////
/////////////////// STATIC METHODS //////////////////////
/////////////////////////////////////////////////////////
/// <summary>
/// This method calculates the Dominance for a CFG (Recursivly)
/// </summary>
/// <param name="root">Root of a CFG</param>
public static void calculateDominanceDataforCFG(GraphNode root,BackEdgesList backEdgeList)
{
if (root == null) //Stoping condition
return;
if (root.DominatorsList.Count == 0) //If i am empty (it means I am the true root of the tree)
root.dom(root.DominatorsList);
//PostOrderTraverse
if (root.branch1 != null)
{
if (root.branch1.dom(root.DominatorsList) == true) //If it's not a back edge
calculateDominanceDataforCFG(root.branch1, backEdgeList);
else
{
backEdgeList.Add(root.ID,root.branch1.ID);
} //TODO:deal with backedge
}
if (root.branch2 != null)
{
if (root.branch2.dom(root.DominatorsList) == true) //if it's not a back edge
calculateDominanceDataforCFG(root.branch2, backEdgeList);
else
{
backEdgeList.Add(root.ID, root.branch2.ID); ;
} //TODO: deal with backedge
}
}
/// <summary>
/// This is a recursive method that extract the nodes that belong to the body of the loop.
/// </summary>
/// <param name="root">The node that is the target of the backedge</param>
/// <param name="source">the first node ID, the target of the backedge</param>
/// <param name="target">the ID of the last node in the loop, the source of the backedge</param>
/// <param name="loopBody">This is a dictionary that will be used to store the nodes that belong to the body of the loop</param>
/// <returns>false if the root doesn't belong to the loop body, otherwize true</returns>
private bool getLoopBodyFromHeaderToLast(GraphNode root, String source,String target,Dictionary<String,GraphNode> loopBody)
{
if (root == null) return false;
if (!root.DominatorsList.ContainsKey(source)) return false; //if the root is not dominated by the loop entrence return false
if (loopBody.ContainsKey(root.ID)) return true; //if root is allready in the loop return true;
if (root.ID == target) //if the root is the target add it to the loopBody
{
if (!loopBody.ContainsKey(root.ID)) //prevent duplicates
loopBody.Add(root.ID, root);
return true;
}
bool returnValue = false;
//Try going to the first branch
if (getLoopBodyFromHeaderToLast(root.Branch1, source, target, loopBody) && root.DominatorsList.ContainsKey(source))
{
if (!loopBody.ContainsKey(root.ID)) //prevent duplicates
loopBody.Add(root.ID, root);
returnValue = true;
}
//Try going to the second branch
if (getLoopBodyFromHeaderToLast(root.Branch2, source, target, loopBody) && root.DominatorsList.ContainsKey(source))
{
if (!loopBody.ContainsKey(root.ID) )
loopBody.Add(root.ID, root);
returnValue = true;
}
return returnValue;
}
/// <summary>
/// Empty constructor
/// </summary>
public IntermidiatCodeAsBasicBlocksCFG()
{
root = null;
cfgBackEdgesList = null;
}
/// <summary>
/// This method reads a graph input file and builds a tree
/// of it
/// </summary>
/// <param name="filePath"></param>
public IntermidiatCodeAsBasicBlocksCFG parsVCGfile(String filePath)
{
TextReader tr = new StreamReader(filePath);
String line = "";
String basicBlockCode = "";
String intermidiatCodeInBasicBlocks = "";
Dictionary<String, GraphNode> basicBlockDictionary = new Dictionary<string, GraphNode>(); //Dictionary will be used for indexing
BackEdgesList backEdgeList = new BackEdgesList();
IntermidiatCodeAsBasicBlocksCFG code = new IntermidiatCodeAsBasicBlocksCFG();
GraphNode root = null;
while ((line = tr.ReadLine()) != null) //read the file till the end
{
if (line.Contains("node")) //Create nodes
{
GraphNode basicBlock = new GraphNode();
line = tr.ReadLine(); //get basic block header
int titleIndex = line.IndexOf('\"')+1;
line = line.Substring(titleIndex);
titleIndex = line.IndexOf('\"');
line = line.Substring(0, titleIndex);
intermidiatCodeInBasicBlocks += "==============================\n";
intermidiatCodeInBasicBlocks += "Basic Block Title = " + line +"\n";
intermidiatCodeInBasicBlocks += "==============================\n";
basicBlock.ID = line;
//Extract the basic blocks code from the file
basicBlockCode = "";
while (!(line = tr.ReadLine()).Contains('}'))
basicBlockCode += line +"\n";
if (line.Contains('['))
{
line = line.Split('}')[0];
line = line.Substring(0, line.Length - 2);
basicBlockCode += line + "\n";
}
intermidiatCodeInBasicBlocks += basicBlockCode;
basicBlock.BasicBlockCode = basicBlockCode;
basicBlockDictionary.Add(basicBlock.ID, basicBlock); //Add basic block to list
if (root == null)
root = basicBlock;
intermidiatCodeInBasicBlocks += "\n";
}
if (line.Contains("edge:")) //Connect nodes
{
line = tr.ReadLine(); //Read color settings of edge
line = tr.ReadLine(); //Source
//Read source Basic Block
int titleIndex = line.IndexOf('\"') + 1;
line = line.Substring(titleIndex);
titleIndex = line.IndexOf('\"');
line = line.Substring(0, titleIndex);
GraphNode source = null;
if (basicBlockDictionary.ContainsKey(line)) //Check if label exsists
source = basicBlockDictionary[line];
else
throw new KeyNotFoundException();
//Read Target Basic Block
line = tr.ReadLine(); //Target
titleIndex = line.IndexOf('\"') + 1;
line = line.Substring(titleIndex);
titleIndex = line.IndexOf('\"');
line = line.Substring(0, titleIndex);
GraphNode target;
if (basicBlockDictionary.ContainsKey(line))
target = basicBlockDictionary[line];
else
throw new KeyNotFoundException();
//Attach target Basic block to source basic block
if (source.Branch1 == null)
source.Branch1 = target;
else
source.Branch2 = target;
}
}
tr.Close();
GraphNode.calculateDominanceDataforCFG(root,backEdgeList); //Calculate dominance for tree
code.IntermidiatCodeBasicBlocks = intermidiatCodeInBasicBlocks;
code.CfgBackEdgesList = backEdgeList;
code.Root = root;
return code;
}