Allow viewing the intermediate ILAst steps.

ICSharpCode.Decompiler/ILAst/ILAstOptimizer.cs

@@ -8,16 +8,29 @@ using Decompiler.Rocks;
 
 namespace Decompiler.ControlFlow
 {
+	public enum ILAstOptimizationStep
+	{
+		SplitToMovableBlocks,
+		FindLoops,
+		FindConditions,
+		FlattenNestedMovableBlocks,
+		SimpleGotoRemoval,
+		RemoveDeadLabels,
+		None
+	}
+	
 	public class ILAstOptimizer
 	{
 		Dictionary<ILLabel, ControlFlowNode> labelToCfNode = new Dictionary<ILLabel, ControlFlowNode>();
 		
-		public void Optimize(ILBlock method)
+		public void Optimize(ILBlock method, ILAstOptimizationStep abortBeforeStep = ILAstOptimizationStep.None)
 		{
+			if (abortBeforeStep == ILAstOptimizationStep.SplitToMovableBlocks) return;
 			foreach(ILBlock block in method.GetSelfAndChildrenRecursive<ILBlock>().ToList()) {
 				SplitToMovableBlocks(block);
 			}
 			
+			if (abortBeforeStep == ILAstOptimizationStep.FindLoops) return;
 			foreach(ILBlock block in method.GetSelfAndChildrenRecursive<ILBlock>().Where(b => !(b is ILMoveableBlock)).ToList()) {
 				ControlFlowGraph graph;
 				graph = BuildGraph(block.Body, block.EntryPoint);
@@ -26,6 +39,7 @@ namespace Decompiler.ControlFlow
 				block.Body = FindLoops(new HashSet<ControlFlowNode>(graph.Nodes.Skip(3)), graph.EntryPoint, true);
 			}
 			
+			if (abortBeforeStep == ILAstOptimizationStep.FindConditions) return;
 			foreach(ILBlock block in method.GetSelfAndChildrenRecursive<ILBlock>().Where(b => !(b is ILMoveableBlock)).ToList()) {
 				ControlFlowGraph graph;
 				graph = BuildGraph(block.Body, block.EntryPoint);
@@ -35,8 +49,11 @@ namespace Decompiler.ControlFlow
 			}
 			
 			// OrderNodes(method);
+			if (abortBeforeStep == ILAstOptimizationStep.FlattenNestedMovableBlocks) return;
 			FlattenNestedMovableBlocks(method);
+			if (abortBeforeStep == ILAstOptimizationStep.SimpleGotoRemoval) return;
 			SimpleGotoRemoval(method);
+			if (abortBeforeStep == ILAstOptimizationStep.RemoveDeadLabels) return;
 			RemoveDeadLabels(method);
 		}
 		

ICSharpCode.Decompiler/ILAst/ILAstTypes.cs

@@ -85,7 +85,8 @@ namespace Decompiler
 		
 		public override void WriteTo(ITextOutput output)
 		{
-			EntryPoint.WriteTo(output);
+			if (EntryPoint != null)
+				EntryPoint.WriteTo(output);
 			foreach(ILNode child in this.Body) {
 				child.WriteTo(output);
 				output.WriteLine();

ILSpy/ILAstLanguage.cs

@@ -21,6 +21,7 @@ using System.Collections.Generic;
 using System.IO;
 using System.Linq;
 using Decompiler;
+using Decompiler.ControlFlow;
 using Decompiler.Transforms;
 using ICSharpCode.Decompiler;
 using ICSharpCode.NRefactory.CSharp;
@@ -33,17 +34,26 @@ namespace ICSharpCode.ILSpy
 	/// </summary>
 	public class ILAstLanguage : Language
 	{
+		string name;
+		bool inlineVariables = true;
+		ILAstOptimizationStep? abortBeforeStep;
+		
 		public override string Name {
 			get {
-				return "ILAst";
+				return name;
 			}
 		}
 		
 		public override void DecompileMethod(MethodDefinition method, ITextOutput output, DecompilationOptions options)
 		{
-			var body = new ILAstBuilder().Build(method, false);
+			ILBlock ilMethod = new ILBlock();
+			ilMethod.Body = new ILAstBuilder().Build(method, inlineVariables);
+			
+			if (abortBeforeStep != null) {
+				new ILAstOptimizer().Optimize(ilMethod, abortBeforeStep.Value);
+			}
 			
-			foreach (ILNode node in body) {
+			foreach (ILNode node in ilMethod.Body) {
 				node.WriteTo(output);
 				output.WriteLine();
 			}
@@ -52,7 +62,13 @@ namespace ICSharpCode.ILSpy
 		#if DEBUG
 		internal static IEnumerable<ILAstLanguage> GetDebugLanguages()
 		{
-			yield return new ILAstLanguage();
+			yield return new ILAstLanguage { name = "ILAst (unoptimized)", inlineVariables = false };
+			string nextName = "ILAst (variable inlining)";
+			foreach (ILAstOptimizationStep step in Enum.GetValues(typeof(ILAstOptimizationStep))) {
+				yield return new ILAstLanguage { name = nextName, abortBeforeStep = step };
+				nextName = "ILAst (after " + step + ")";
+				
+			}
 		}
 		#endif