public void RedirectPredecessors()
{
if (this.Parent.Entry == OriginalCFGConstruct)
{
this.Parent.Entry = this;
}
foreach (CFGBlockLogicalConstruct predecessor in OriginalCFGConstruct.CFGPredecessors)
{
predecessor.RemoveFromSuccessors(OriginalCFGConstruct);
predecessor.AddToSuccessors(this);
this.AddToPredecessors(predecessor);
LogicalConstructBase currentPredecessorParent = predecessor.Parent as LogicalConstructBase;
while (currentPredecessorParent != null)
{
if (currentPredecessorParent.RemoveFromSuccessors(OriginalCFGConstruct))
{
currentPredecessorParent.AddToSuccessors(this);
}
currentPredecessorParent = currentPredecessorParent.Parent as LogicalConstructBase;
}
}
}
/// <summary>
/// Redirect the predecessors and successors of the finally block.
/// </summary>
/// <remarks>
/// Check if the finallyBlockEntry is only reachable by nodes in the try block.
/// Make the successor of the finallyBlockEnd successor to all of the predecessors of the finallyBlockEntry.
/// This will detach the finally block from the subgraph, which is a desired result since every normal finally block is not reachable from any where
/// (the CLR takes care of executing the code in the finally block).
/// </remarks>
/// <param name="finallyBlockEntry"></param>
/// <param name="finallyBlockEnd"></param>
/// <returns>The successor of the finally block.</returns>
private CFGBlockLogicalConstruct ProcessFinallyNode(CFGBlockLogicalConstruct finallyBlockEntry, CFGBlockLogicalConstruct finallyBlockEnd)
{
foreach (ILogicalConstruct predecessor in finallyBlockEntry.SameParentPredecessors)
{
if (!newTryBody.Contains(predecessor))
{
throw new Exception("Invalid entry to the finally block");
}
}
CFGBlockLogicalConstruct finallySuccessor;
using (IEnumerator <CFGBlockLogicalConstruct> enumerator = finallyBlockEnd.CFGSuccessors.GetEnumerator())
{
enumerator.MoveNext();
finallySuccessor = enumerator.Current;
if (enumerator.MoveNext())
{
throw new Exception("Invalid count of successors");
}
}
HashSet <CFGBlockLogicalConstruct> finallyCFGPredecessors = new HashSet <CFGBlockLogicalConstruct>(finallyBlockEntry.CFGPredecessors);
foreach (CFGBlockLogicalConstruct cfgPredecessor in finallyCFGPredecessors)
{
if (cfgPredecessor.TheBlock != finallyBlockEntry.TheBlock && cfgPredecessor.TheBlock.Successors.Length > 1)
{
ProcessMultiWayCFGPredecessor(finallyBlockEntry, cfgPredecessor.TheBlock, finallySuccessor.TheBlock);
}
LogicalConstructBase currenConstruct = cfgPredecessor;
while (currenConstruct != finallyBlockEntry.Parent)
{
currenConstruct.RemoveFromSuccessors(finallyBlockEntry);
currenConstruct.AddToSuccessors(finallySuccessor);
currenConstruct = currenConstruct.Parent as LogicalConstructBase;
}
finallySuccessor.AddToPredecessors(cfgPredecessor);
finallyBlockEntry.RemoveFromPredecessors(cfgPredecessor);
}
finallySuccessor.RemoveFromPredecessors(finallyBlockEnd);
finallyBlockEnd.RemoveFromSuccessors(finallySuccessor);
return(finallySuccessor);
}