Replace 'endfinally' with 'leave'

ICSharpCode.Decompiler/IL/BlockBuilder.cs

@@ -175,8 +175,14 @@ namespace ICSharpCode.Decompiler.IL
 			switch (inst.OpCode) {
 				case OpCode.Branch:
 					var branch = (Branch)inst;
+					Debug.Assert(branch.TargetBlock == null);
 					branch.TargetBlock = FindBranchTarget(branch.TargetILOffset);
 					break;
+				case OpCode.Leave:
+					var leave = (Leave)inst;
+					Debug.Assert(leave.TargetContainer == null);
+					leave.TargetContainer = containerStack.Peek();
+					break;
 				case OpCode.BlockContainer:
 					var container = (BlockContainer)inst;
 					containerStack.Push(container);

ICSharpCode.Decompiler/IL/ILReader.cs

@@ -431,7 +431,7 @@ namespace ICSharpCode.Decompiler.IL
 					return new Peek(stack.Count > 0 ? stack.Peek() : StackType.Unknown);
 				case ILOpCode.Endfilter:
 				case ILOpCode.Endfinally:
-					return new EndFinally();
+					return new Leave(null);
 				case ILOpCode.Initblk:
 					throw new NotImplementedException();
 				case ILOpCode.Jmp:

ICSharpCode.Decompiler/IL/InstructionFlags.cs

@@ -81,6 +81,10 @@ namespace ICSharpCode.Decompiler.IL
 		/// <summary>
 		/// The instruction performs unconditional control flow, so that its endpoint is unreachable.
 		/// </summary>
+		/// <remarks>
+		/// If EndPointUnreachable is set, either MayThrow or MayBranch should also be set
+		/// (unless the instruction represents an infinite loop).
+		/// </remarks>
 		EndPointUnreachable = 0x400,
 	}
 }

ICSharpCode.Decompiler/IL/Instructions.cs

@@ -68,8 +68,6 @@ namespace ICSharpCode.Decompiler.IL
 		Branch,
 		/// <summary>Unconditional branch to end of block container. <c>goto container_end;</c>, often <c>break;</c></summary>
 		Leave,
-		/// <summary>Marks the end of an finally, fault or exception filter block.</summary>
-		EndFinally,
 		/// <summary>If statement / conditional expression. <c>if (condition) trueExpr else falseExpr</c></summary>
 		IfInstruction,
 		/// <summary>Try-catch statement.</summary>
@@ -701,27 +699,6 @@ namespace ICSharpCode.Decompiler.IL
 		}
 	}
 
-	/// <summary>Marks the end of an finally, fault or exception filter block.</summary>
-	public sealed partial class EndFinally : SimpleInstruction
-	{
-		public EndFinally() : base(OpCode.EndFinally)
-		{
-		}
-		public override StackType ResultType { get { return StackType.Void; } }
-		protected override InstructionFlags ComputeFlags()
-		{
-			return InstructionFlags.EndPointUnreachable | InstructionFlags.MayBranch;
-		}
-		public override void AcceptVisitor(ILVisitor visitor)
-		{
-			visitor.VisitEndFinally(this);
-		}
-		public override T AcceptVisitor<T>(ILVisitor<T> visitor)
-		{
-			return visitor.VisitEndFinally(this);
-		}
-	}
-
 	/// <summary>If statement / conditional expression. <c>if (condition) trueExpr else falseExpr</c></summary>
 	public sealed partial class IfInstruction : ILInstruction
 	{
@@ -2737,10 +2714,6 @@ namespace ICSharpCode.Decompiler.IL
 		{
 			Default(inst);
 		}
-		protected internal virtual void VisitEndFinally(EndFinally inst)
-		{
-			Default(inst);
-		}
 		protected internal virtual void VisitIfInstruction(IfInstruction inst)
 		{
 			Default(inst);
@@ -3039,10 +3012,6 @@ namespace ICSharpCode.Decompiler.IL
 		{
 			return Default(inst);
 		}
-		protected internal virtual T VisitEndFinally(EndFinally inst)
-		{
-			return Default(inst);
-		}
 		protected internal virtual T VisitIfInstruction(IfInstruction inst)
 		{
 			return Default(inst);
@@ -3328,7 +3297,6 @@ namespace ICSharpCode.Decompiler.IL
 			"arglist",
 			"br",
 			"leave",
-			"endfinally",
 			"if",
 			"try.catch",
 			"try.catch.handler",

ICSharpCode.Decompiler/IL/Instructions.tt

@@ -63,9 +63,6 @@
 			CustomClassName("Branch"), NoArguments, CustomConstructor, UnconditionalBranch, MayBranch, CustomComputeFlags),
 		new OpCode("leave", "Unconditional branch to end of block container. <c>goto container_end;</c>, often <c>break;</c>",
 			NoArguments, CustomConstructor, UnconditionalBranch, MayBranch, CustomComputeFlags),
-		// TODO: get rid of endfinally, we can represent those with 'leave blockcontainer' instead
-		new OpCode("endfinally", "Marks the end of an finally, fault or exception filter block.",
-			CustomClassName("EndFinally"), NoArguments, UnconditionalBranch, MayBranch),
 		new OpCode("if", "If statement / conditional expression. <c>if (condition) trueExpr else falseExpr</c>",
 			CustomClassName("IfInstruction"),
 			CustomChildren(new []{

ICSharpCode.Decompiler/IL/Instructions/Leave.cs

@@ -47,8 +47,8 @@ namespace ICSharpCode.Decompiler.IL
 		
 		public Leave(BlockContainer targetContainer) : base(OpCode.Leave)
 		{
-			if (targetContainer == null)
-				throw new ArgumentNullException("targetContainer");
+			// Note: ILReader will create Leave instructions with targetContainer==null to represent 'endfinally',
+			// the targetContainer will then be filled in by BlockBuilder
 			this.targetContainer = targetContainer;
 		}
 		
@@ -88,20 +88,22 @@ namespace ICSharpCode.Decompiler.IL
 		}
 		
 		public string TargetLabel {
-			get { return targetContainer.EntryPoint.Label; }
+			get { return targetContainer != null ? targetContainer.EntryPoint.Label : string.Empty; }
 		}
 		
 		internal override void CheckInvariant()
 		{
 			base.CheckInvariant();
-			Debug.Assert(this.IsDescendantOf(targetContainer));
+			Debug.Assert(targetContainer == null || this.IsDescendantOf(targetContainer));
 		}
 		
 		public override void WriteTo(ITextOutput output)
 		{
 			output.Write(OpCode);
-			output.Write(' ');
-			output.WriteReference(TargetLabel, targetContainer, isLocal: true);
+			if (targetContainer != null) {
+				output.Write(' ');
+				output.WriteReference(TargetLabel, targetContainer, isLocal: true);
+			}
 			if (PopCount != 0) {
 				output.Write(" (pops ");
 				output.Write(PopCount.ToString());

ICSharpCode.Decompiler/IL/Transforms/LoopDetection.cs

@@ -31,7 +31,7 @@ namespace ICSharpCode.Decompiler.IL.Transforms
 	/// * LoopDetection should run before other control flow structures are detected.
 	/// * Blocks should be basic blocks (not extended basic blocks) so that the natural loops
 	/// don't include more instructions than strictly necessary.
-	/// * (depending on future loop detection improvements:) Loop detection should run after the 'return block' is duplicated.
+	/// * (depending on future loop detection improvements:) Loop detection should run after the 'return block' is duplicated (OptimizingTransform).
 	/// </remarks>
 	public class LoopDetection : IILTransform
 	{