private static Node ReconstructNodes(SubroutineGraph newGraph, SubroutineGraph oldGraph, Node startNode, Decompiler.SubroutineContext decompileContext, Dictionary <Node, Node> mapping, List <Tuple <Node, Node, Jump.JumpType> > futureJumps)
{
List <Node> children = new List <Node>();
Node result; // new TextNode(startNode.ToString());
//Stack<Expression> stackAfterThisNode = decompileContext.Stack;
//Expression conditional = null; // Pop the condition of an if / while before decompiling the following chunks
if (startNode is TextNode textStart)
{
result = new TextNode(textStart.Text);
}
else if (startNode is SAGESharp.OSI.ControlFlow.OSINode osiStart)
{
//result = new OSINode(osiStart.Instructions);
List <InstructionStatement> statements = Decompiler.DecompileSubroutineChunk(decompileContext, osiStart.Instructions);
result = new LSSNode(statements, startNode.OutAlwaysJump == null ? decompileContext.Stack.Pop() : null);
/*if (startNode.OutAlwaysJump == null)
* {
* conditional = decompileContext.Stack.Pop();
* }*/
}
else if (startNode is LSSNode lssStart)
{
result = new LSSNode(lssStart.Statements /*, lssStart.StackLeftOver*/, lssStart.EndConditional);
}
else
{
throw new Exception("o no");
}
foreach (Jump outJump in startNode.OutJumps.Values)
{
if (outJump.Destination == oldGraph.EndNode)
{
result.CreateJumpTo(newGraph.EndNode, outJump.Type);
}
else
{
if (!mapping.ContainsKey(outJump.Destination))
{
// Reconstruct the destination
mapping.Add(outJump.Destination, null); // Placeholder to avoid stack overflow
Node newOutJumpTarget = ReconstructNodes(newGraph, oldGraph, outJump.Destination, decompileContext.CloneStack(), mapping, futureJumps);
newGraph.Nodes.Add(newOutJumpTarget);
mapping[outJump.Destination] = newOutJumpTarget;
result.CreateJumpTo(mapping[outJump.Destination], outJump.Type);
}
else if (mapping[outJump.Destination] == null)
{
// We are in the process of reconstructing the destination, so add to later jumps.
futureJumps.Add(new Tuple <Node, Node, Jump.JumpType>(startNode, outJump.Destination, outJump.Type));
}
else
{
// The destination is reconstructed and ready to go
result.CreateJumpTo(mapping[outJump.Destination], outJump.Type);
}
}
}
for (int i = futureJumps.Count - 1; i >= 0; i--)
{
Tuple <Node, Node, Jump.JumpType> futureJump = futureJumps[i];
if (mapping.ContainsKey(futureJump.Item1) && mapping.ContainsKey(futureJump.Item2) &&
mapping[futureJump.Item1] != null && mapping[futureJump.Item2] != null)
{
mapping[futureJump.Item1].CreateJumpTo(mapping[futureJump.Item2], futureJump.Item3);
futureJumps.RemoveAt(i);
}
}
return(result);
}
private static void AnalyzeIfElse(SubroutineGraph graph, LSSNode node, Stack <Node> wipNodes)
{
wipNodes.Push(node);
foreach (Jump outJump in node.OutJumps.Values)
{
if (outJump.Destination is LSSNode lssDestination)
{
if (!wipNodes.Contains(outJump.Destination))
{
AnalyzeIfElse(graph, lssDestination, wipNodes);
}
}
else if (outJump.Destination == graph.EndNode)
{
}
else
{
throw new Exception("o no!");
}
}
if (node.OutTrueJump != null && node.OutFalseJump != null && node.OutJumps.Count == 2)
{
if (node.OutTrueJump.Destination.OutAlwaysJump != null &&
node.OutTrueJump.Destination.OutAlwaysJump.Destination == node.OutFalseJump.Destination &&
node.OutTrueJump.Destination.OutJumps.Count == 1)
{
// If branch
// Remove outTrueJump's node and add the text to node, and then switch over all the jumps that came from out of outTrueJump's node
LSSNode trueNode = node.OutTrueJump.Destination as LSSNode;
node.Statements.Add(new IfStatement(new SourceSpan(), node.EndConditional, new BlockStatement(new SourceSpan(), trueNode.Statements), null));;
trueNode.OutAlwaysJump.Destination.InJumps.Remove(trueNode);
node.OutJumps.Remove(trueNode);
Node alwaysNode = node.OutFalseJump.Destination;
node.OutJumps.Remove(alwaysNode);
alwaysNode.InJumps.Remove(node);
graph.Nodes.Remove(trueNode);
node.CreateJumpTo(alwaysNode, Jump.JumpType.Always);
}
else if (node.OutTrueJump.Destination.OutAlwaysJump != null &&
node.OutFalseJump.Destination.OutAlwaysJump != null &&
node.OutTrueJump.Destination.OutAlwaysJump.Destination == node.OutFalseJump.Destination.OutAlwaysJump.Destination)
{
// If & Else branches
LSSNode trueNode = node.OutTrueJump.Destination as LSSNode;
LSSNode falseNode = node.OutFalseJump.Destination as LSSNode;
Node alwaysNode = trueNode.OutAlwaysJump.Destination;
IfStatement elseIf = null;
if (falseNode?.Statements.Count == 1 && falseNode.Statements[0] is IfStatement innerIf)
{
elseIf = innerIf;
}
else
{
elseIf = new IfStatement(new SourceSpan(), null, new BlockStatement(new SourceSpan(), falseNode.Statements), null);
}
IfStatement ifStatement = new IfStatement(new SourceSpan(), node.EndConditional, new BlockStatement(new SourceSpan(), trueNode.Statements), elseIf);
node.Statements.Add(ifStatement);
// HACK: If we are coming from a switch statement (where the conditions use Dup, ???, EqualTo), shave off the Pop-ed expressiont that was switched
if (node.EndConditional is BinaryExpression binExpr && binExpr.Operation.Type == TokenType.EqualsEquals && binExpr.Left is Expression dupedExpr)
{
bool same = true;
IfStatement stmt = ifStatement;
while (stmt != null && same)
{
if (stmt.Condition is BinaryExpression condBinExpr && condBinExpr.Operation.Type == TokenType.EqualsEquals && condBinExpr.Left == dupedExpr)
{
same = true;
}
else
{
same = false;
}
stmt = stmt.ElseStatement;
}
if (same && alwaysNode is LSSNode always && always.Statements.Count >= 1 && always.Statements[0] is ExpressionStatement extraStmt && !(extraStmt.Expression is CallExpression))
{
always.Statements.RemoveAt(0);
}
}
