private SwitchStatement(Statement head, Statement poststat)
: this()
{
first = head;
stats.AddWithKey(head, head.id);
// find post node
HashSet <Statement> lstNodes = new HashSet <Statement>(head.GetNeighbours(StatEdge.
Type_Regular, Direction_Forward));
// cluster nodes
if (poststat != null)
{
post = poststat;
lstNodes.Remove(post);
}
default_edge = head.GetSuccessorEdges(Statement.Statedge_Direct_All)[0];
foreach (Statement st in lstNodes)
{
stats.AddWithKey(st, st.id);
}
}
public virtual void CollapseNodesToStatement(Statement stat)
{
Statement head = stat.GetFirst();
Statement post = stat.GetPost();
VBStyleCollection <Statement, int> setNodes = stat.GetStats();
// post edges
if (post != null)
{
foreach (StatEdge edge in post.GetEdges(Statedge_Direct_All, Direction_Backward))
{
if (stat.ContainsStatementStrict(edge.GetSource()))
{
edge.GetSource().ChangeEdgeType(Direction_Forward, edge, StatEdge.Type_Break);
stat.AddLabeledEdge(edge);
}
}
}
// regular head edges
foreach (StatEdge prededge in head.GetAllPredecessorEdges())
{
if (prededge.GetType() != StatEdge.Type_Exception && stat.ContainsStatementStrict
(prededge.GetSource()))
{
prededge.GetSource().ChangeEdgeType(Direction_Forward, prededge, StatEdge.Type_Continue
);
stat.AddLabeledEdge(prededge);
}
head.RemovePredecessor(prededge);
prededge.GetSource().ChangeEdgeNode(Direction_Forward, prededge, stat);
stat.AddPredecessor(prededge);
}
if (setNodes.ContainsKey(first.id))
{
first = stat;
}
// exception edges
HashSet <Statement> setHandlers = new HashSet <Statement>(head.GetNeighbours(StatEdge
.Type_Exception, Direction_Forward));
foreach (Statement node in setNodes)
{
setHandlers.UnionWith(node.GetNeighbours(StatEdge.Type_Exception, Direction_Forward
));
}
if (!(setHandlers.Count == 0))
{
foreach (StatEdge edge in head.GetEdges(StatEdge.Type_Exception, Direction_Forward
))
{
Statement handler = edge.GetDestination();
if (setHandlers.Contains(handler))
{
if (!setNodes.ContainsKey(handler.id))
{
stat.AddSuccessor(new StatEdge(stat, handler, edge.GetExceptions()));
}
}
}
foreach (Statement node in setNodes)
{
foreach (StatEdge edge in node.GetEdges(StatEdge.Type_Exception, Direction_Forward
))
{
if (setHandlers.Contains(edge.GetDestination()))
{
node.RemoveSuccessor(edge);
}
}
}
}
if (post != null && !stat.GetNeighbours(StatEdge.Type_Exception, Direction_Forward
).Contains(post))
{
// TODO: second condition redundant?
stat.AddSuccessor(new StatEdge(StatEdge.Type_Regular, stat, post));
}
// adjust statement collection
foreach (Statement st in setNodes)
{
stats.RemoveWithKey(st.id);
}
stats.AddWithKey(stat, stat.id);
stat.SetAllParent();
stat.SetParent(this);
stat.BuildContinueSet();
// monitorenter and monitorexit
stat.BuildMonitorFlags();
if (stat.type == Type_Switch)
{
// special case switch, sorting leaf nodes
((SwitchStatement)stat).SortEdgesAndNodes();
}
}
// *****************************************************************************
// private methods
// *****************************************************************************
public virtual void SortEdgesAndNodes()
{
Dictionary <StatEdge, int> mapEdgeIndex = new Dictionary <StatEdge, int>();
List <StatEdge> lstFirstSuccs = first.GetSuccessorEdges(Statedge_Direct_All);
for (int i = 0; i < lstFirstSuccs.Count; i++)
{
Sharpen.Collections.Put(mapEdgeIndex, lstFirstSuccs[i], i == 0 ? lstFirstSuccs.Count
: i);
}
// case values
BasicBlockStatement bbstat = (BasicBlockStatement)first;
int[] values = ((SwitchInstruction)bbstat.GetBlock().GetLastInstruction()).GetValues
();
List <Statement> nodes = new List <Statement>(stats.Count - 1);
List <List <int?> > edges = new List <List <int?> >(stats.Count - 1);
// collect regular edges
for (int i = 1; i < stats.Count; i++)
{
Statement stat = stats[i];
List <int?> lst = new List <int?>();
foreach (StatEdge edge in stat.GetPredecessorEdges(StatEdge.Type_Regular))
{
if (edge.GetSource() == first)
{
lst.Add(mapEdgeIndex.GetOrNullable(edge));
}
}
lst.Sort();
nodes.Add(stat);
edges.Add(lst);
}
// collect exit edges
List <StatEdge> lstExitEdges = first.GetSuccessorEdges(StatEdge.Type_Break | StatEdge
.Type_Continue);
while (!(lstExitEdges.Count == 0))
{
StatEdge edge = lstExitEdges[0];
List <int?> lst = new List <int?>();
for (int i = lstExitEdges.Count - 1; i >= 0; i--)
{
StatEdge edgeTemp = lstExitEdges[i];
if (edgeTemp.GetDestination() == edge.GetDestination() && edgeTemp.GetType() == edge
.GetType())
{
lst.Add(mapEdgeIndex.GetOrNullable(edgeTemp));
lstExitEdges.RemoveAtReturningValue(i);
}
}
lst.Sort();
nodes.Add(null);
edges.Add(lst);
}
// sort edges (bubblesort)
for (int i = 0; i < edges.Count - 1; i++)
{
for (int j = edges.Count - 1; j > i; j--)
{
if (edges[j - 1][0] > edges[j][0])
{
edges[j] = edges[j - 1] = edges[j];
nodes[j] = nodes[j - 1] = nodes[j];
}
}
}
// sort statement cliques
for (int index = 0; index < nodes.Count; index++)
{
Statement stat = nodes[index];
if (stat != null)
{
HashSet <Statement> setPreds = new HashSet <Statement>(stat.GetNeighbours(StatEdge.
Type_Regular, Direction_Backward));
setPreds.Remove(first);
if (!(setPreds.Count == 0))
{
Statement pred = new Sharpen.EnumeratorAdapter <Statement>(setPreds.GetEnumerator()).Next();
// assumption: at most one predecessor node besides the head. May not hold true for obfuscated code.
for (int j = 0; j < nodes.Count; j++)
{
if (j != (index - 1) && nodes[j] == pred)
{
nodes.Add(j + 1, stat);
edges.Add(j + 1, edges[index]);
if (j > index)
{
nodes.RemoveAtReturningValue(index);
edges.RemoveAtReturningValue(index);
index--;
}
else
{
nodes.RemoveAtReturningValue(index + 1);
edges.RemoveAtReturningValue(index + 1);
}
break;
}
}
}
}
}
// translate indices back into edges
List <List <StatEdge> > lstEdges = new List <List <StatEdge> >(edges.Count);
List <List <Exprent> > lstValues = new List <List <Exprent> >(edges.Count);
foreach (List <int?> lst in edges)
{
List <StatEdge> lste = new List <StatEdge>(lst.Count);
List <Exprent> lstv = new List <Exprent>(lst.Count);
List <StatEdge> lstSuccs = first.GetSuccessorEdges(Statedge_Direct_All);
foreach (int? @in in lst)
{
int?index = @in == lstSuccs.Count ? 0 : @in;
if (!index.HasValue)
{
continue;
}
lste.Add(lstSuccs[index.Value]);
lstv.Add(index == 0 ? null : new ConstExprent(values[index.Value - 1], false, null));
}
lstEdges.Add(lste);
lstValues.Add(lstv);
}
// replace null statements with dummy basic blocks
for (int i = 0; i < nodes.Count; i++)
{
if (nodes[i] == null)
{
BasicBlockStatement bstat = new BasicBlockStatement(new BasicBlock(DecompilerContext
.GetCounterContainer().GetCounterAndIncrement(CounterContainer.Statement_Counter
)));
StatEdge sample_edge = lstEdges[i][0];
bstat.AddSuccessor(new StatEdge(sample_edge.GetType(), bstat, sample_edge.GetDestination
(), sample_edge.closure));
foreach (StatEdge edge in lstEdges[i])
{
edge.GetSource().ChangeEdgeType(Direction_Forward, edge, StatEdge.Type_Regular);
edge.closure.GetLabelEdges().Remove(edge);
edge.GetDestination().RemovePredecessor(edge);
edge.GetSource().ChangeEdgeNode(Direction_Forward, edge, bstat);
bstat.AddPredecessor(edge);
}
nodes[i] = bstat;
stats.AddWithKey(bstat, bstat.id);
bstat.SetParent(this);
}
}
caseStatements = nodes;
caseEdges = lstEdges;
caseValues = lstValues;
}
