Add more advanced debugging to patcher

Support multiple try-catch operations on a single instruction
Replace long branch with short branch instructions where possible
Dump generated IL at three stages to a file.

Torch.Tests/PatchTest.cs

@@ -1,10 +1,12 @@
 using System;
 using System.Collections.Generic;
+using System.IO;
 using System.Linq;
 using System.Reflection;
 using System.Reflection.Emit;
 using System.Runtime.CompilerServices;
 using System.Text;
+using System.Threading.Tasks;
 using Torch.Managers.PatchManager;
 using Torch.Managers.PatchManager.MSIL;
 using Torch.Utils;
@@ -17,6 +19,7 @@ namespace Torch.Tests
     public class PatchTest
     {
         #region TestRunner
+
         private static readonly PatchManager _patchContext = new PatchManager(null);
 
         [Theory]
@@ -48,6 +51,133 @@ namespace Torch.Tests
         }
 
 
+        [Fact]
+        public void TestTryCatchNop()
+        {
+            var ctx = _patchContext.AcquireContext();
+            ctx.GetPattern(TryCatchTest._target).Transpilers.Add(_nopTranspiler);
+            _patchContext.Commit();
+            Assert.False(TryCatchTest.Target());
+            Assert.True(TryCatchTest.FinallyHit);
+            _patchContext.FreeContext(ctx);
+            _patchContext.Commit();
+        }
+
+        [Fact]
+        public void TestTryCatchCancel()
+        {
+            var ctx = _patchContext.AcquireContext();
+            ctx.GetPattern(TryCatchTest._target).Transpilers.Add(TryCatchTest._removeThrowTranspiler);
+            ctx.GetPattern(TryCatchTest._target).DumpTarget = @"C:\tmp\dump.txt";
+            ctx.GetPattern(TryCatchTest._target).DumpMode = MethodRewritePattern.PrintModeEnum.Original | MethodRewritePattern.PrintModeEnum.Patched;
+            _patchContext.Commit();
+            Assert.True(TryCatchTest.Target());
+            Assert.True(TryCatchTest.FinallyHit);
+            _patchContext.FreeContext(ctx);
+            _patchContext.Commit();
+        }
+
+        private static readonly MethodInfo _nopTranspiler = typeof(PatchTest).GetMethod(nameof(NopTranspiler), BindingFlags.Static | BindingFlags.NonPublic);
+
+        private static IEnumerable<MsilInstruction> NopTranspiler(IEnumerable<MsilInstruction> input)
+        {
+            return input;
+        }
+
+        private class TryCatchTest
+        {
+            public static readonly MethodInfo _removeThrowTranspiler =
+                typeof(TryCatchTest).GetMethod(nameof(RemoveThrowTranspiler), BindingFlags.Static | BindingFlags.NonPublic);
+
+            private static IEnumerable<MsilInstruction> RemoveThrowTranspiler(IEnumerable<MsilInstruction> input)
+            {
+                foreach (var i in input)
+                    if (i.OpCode == OpCodes.Throw)
+                        yield return i.CopyWith(OpCodes.Pop);
+                    else
+                        yield return i;
+            }
+
+            public static readonly MethodInfo _target = typeof(TryCatchTest).GetMethod(nameof(Target), BindingFlags.Public | BindingFlags.Static);
+
+            public static bool FinallyHit = false;
+
+            public static bool Target()
+            {
+                FinallyHit = false;
+                try
+                {
+                    try
+                    {
+                        // shim to prevent compiler optimization
+                        if ("test".Length > "".Length)
+                            throw new Exception();
+                        return true;
+                    }
+                    catch (IOException ioe)
+                    {
+                        return false;
+                    }
+                    catch (Exception e)
+                    {
+                        return false;
+                    }
+                    finally
+                    {
+                        FinallyHit = true;
+                    }
+                }
+                catch (Exception e)
+                {
+                    throw;
+                }
+            }
+        }
+
+        [Fact]
+        public void TestAsyncNop()
+        {
+            var candidates = new List<Type>();
+            var nestedTypes = typeof(PatchTest).GetNestedTypes(BindingFlags.NonPublic | BindingFlags.Static);
+            foreach (var nested in nestedTypes)
+                if (nested.Name.StartsWith("<" + nameof(TestAsyncMethod) + ">"))
+                {
+                    var good = false;
+                    foreach (var itf in nested.GetInterfaces())
+                        if (itf.FullName == typeof(IAsyncStateMachine).FullName)
+                        {
+                            good = true;
+                            break;
+                        }
+
+                    if (good)
+                        candidates.Add(nested);
+                }
+
+            if (candidates.Count != 1)
+                throw new Exception("Couldn't find async worker");
+
+            var method = candidates[0].GetMethod("MoveNext", BindingFlags.Instance | BindingFlags.NonPublic | BindingFlags.Public);
+            if (method == null)
+                throw new Exception("Failed to find state machine move next instruction, cannot proceed");
+
+            var ctx = _patchContext.AcquireContext();
+            ctx.GetPattern(method).Transpilers.Add(_nopTranspiler);
+            ctx.GetPattern(method).DumpTarget = @"C:\tmp\dump.txt";
+            ctx.GetPattern(method).DumpMode = MethodRewritePattern.PrintModeEnum.Original | MethodRewritePattern.PrintModeEnum.Patched;
+            _patchContext.Commit();
+            
+            Assert.Equal("TEST", TestAsyncMethod().Result);
+            _patchContext.FreeContext(ctx);
+            _patchContext.Commit();
+        }
+        
+        private async Task<string> TestAsyncMethod()
+        {
+            var first = await Task.Run(() => "TE");
+            var last = await Task.Run(() => "ST");
+            return await Task.Run(() => first + last);
+        }
 
         public class TestBootstrap
         {
@@ -189,6 +319,7 @@ namespace Torch.Tests
         public static IEnumerable<object[]> Transpilers => _patchTest.Where(x => x.HasTranspile).Select(x => new object[] {x});
         public static IEnumerable<object[]> Suffixes => _patchTest.Where(x => x.HasSuffix).Select(x => new object[] {x});
         public static IEnumerable<object[]> Combo => _patchTest.Where(x => x.HasPrefix || x.HasTranspile || x.HasSuffix).Select(x => new object[] {x});
+
         #endregion
 
         #region PatchTests
@@ -220,7 +351,8 @@ namespace Torch.Tests
             {
                 yield return new MsilInstruction(OpCodes.Ldnull);
                 yield return new MsilInstruction(OpCodes.Ldc_I4_1);
-                yield return new MsilInstruction(OpCodes.Stfld).InlineValue(typeof(StaticNoRetNoParm).GetField("_transpileHit", BindingFlags.Static | BindingFlags.NonPublic | BindingFlags.Public));
+                yield return new MsilInstruction(OpCodes.Stfld).InlineValue(typeof(StaticNoRetNoParm).GetField("_transpileHit",
+                    BindingFlags.Static | BindingFlags.NonPublic | BindingFlags.Public));
                 foreach (MsilInstruction i in instructions)
                     yield return i;
             }
@@ -380,6 +512,7 @@ namespace Torch.Tests
                 Assert.True(_prefixHit, "Failed to prefix");
             }
         }
+
         #endregion
     }
 #pragma warning restore 414

Torch/Managers/PatchManager/DecoratedMethod.cs

@@ -2,6 +2,7 @@
 using System.Collections.Generic;
 using System.ComponentModel.Design;
 using System.Diagnostics;
+using System.IO;
 using System.Linq;
 using System.Reflection;
 using System.Reflection.Emit;
@@ -44,7 +45,7 @@ namespace Torch.Managers.PatchManager
 
                 if (Prefixes.Count == 0 && Suffixes.Count == 0 && Transpilers.Count == 0 && PostTranspilers.Count == 0)
                     return;
-                _log.Log(PrintMsil ? LogLevel.Info : LogLevel.Debug,
+                _log.Log(PrintMode != 0 ? LogLevel.Info : LogLevel.Debug,
                     $"Begin patching {_method.DeclaringType?.FullName}#{_method.Name}({string.Join(", ", _method.GetParameters().Select(x => x.ParameterType.Name))})");
                 var patch = ComposePatchedMethod();
 
@@ -52,7 +53,7 @@ namespace Torch.Managers.PatchManager
                 var newAddress = AssemblyMemory.GetMethodBodyStart(patch);
                 _revertData = AssemblyMemory.WriteJump(_revertAddress, newAddress);
                 _pinnedPatch = GCHandle.Alloc(patch);
-                _log.Log(PrintMsil ? LogLevel.Info : LogLevel.Debug,
+                _log.Log(PrintMode != 0 ? LogLevel.Info : LogLevel.Debug,
                     $"Done patching {_method.DeclaringType?.FullName}#{_method.Name}({string.Join(", ", _method.GetParameters().Select(x => x.ParameterType.Name))})");
             }
             catch (Exception exception)
@@ -104,17 +105,74 @@ namespace Torch.Managers.PatchManager
         public const string PREFIX_SKIPPED_PARAMETER = "__prefixSkipped";
         public const string LOCAL_PARAMETER = "__local";
 
+        private void SavePatchedMethod(string target)
+        {
+            var asmBuilder =
+                AppDomain.CurrentDomain.DefineDynamicAssembly(new AssemblyName("SomeName"), AssemblyBuilderAccess.RunAndSave, Path.GetDirectoryName(target));
+            var moduleBuilder = asmBuilder.DefineDynamicModule(Path.GetFileNameWithoutExtension(target), Path.GetFileName(target));
+            var typeBuilder = moduleBuilder.DefineType("Test", TypeAttributes.Public);
+
+
+            var methodName = _method.Name + $"_{_patchSalt}";
+            var returnType = _method is MethodInfo meth ? meth.ReturnType : typeof(void);
+            var parameters = _method.GetParameters();
+            var parameterTypes = (_method.IsStatic ? Enumerable.Empty<Type>() : new[] {_method.DeclaringType})
+                .Concat(parameters.Select(x => x.ParameterType)).ToArray();
+
+            var patchMethod = typeBuilder.DefineMethod(methodName, MethodAttributes.Public | MethodAttributes.Static, CallingConventions.Standard,
+                returnType, parameterTypes);
+            if (!_method.IsStatic)
+                patchMethod.DefineParameter(0, ParameterAttributes.None, INSTANCE_PARAMETER);
+            for (var i = 0; i < parameters.Length; i++)
+                patchMethod.DefineParameter((patchMethod.IsStatic ? 0 : 1) + i, parameters[i].Attributes, parameters[i].Name);
+
+            var generator = new LoggingIlGenerator(patchMethod.GetILGenerator(), LogLevel.Trace);
+            List<MsilInstruction> il = EmitPatched((type, pinned) => new MsilLocal(generator.DeclareLocal(type, pinned))).ToList();
+
+            MethodTranspiler.EmitMethod(il, generator);
+
+            Type res = typeBuilder.CreateType();
+            asmBuilder.Save(Path.GetFileName(target));
+            foreach (var method in res.GetMethods(BindingFlags.Public | BindingFlags.Static))
+                _log.Info($"Information " + method);
+        }
 
         public DynamicMethod ComposePatchedMethod()
         {
             DynamicMethod method = AllocatePatchMethod();
-            var generator = new LoggingIlGenerator(method.GetILGenerator(), PrintMsil ? LogLevel.Info : LogLevel.Trace);
+            var generator = new LoggingIlGenerator(method.GetILGenerator(),
+                PrintMode.HasFlag(PrintModeEnum.EmittedReflection) ? LogLevel.Info : LogLevel.Trace);
             List<MsilInstruction> il = EmitPatched((type, pinned) => new MsilLocal(generator.DeclareLocal(type, pinned))).ToList();
-            if (PrintMsil)
+
+            var dumpTarget = DumpTarget != null ? File.CreateText(DumpTarget) : null;
+            try
+            {
+                const string gap = "\n\n\n\n\n";
+
+                void LogTarget(PrintModeEnum mode, bool err, string msg)
+                {
+                    if (DumpMode.HasFlag(mode))
+                        dumpTarget?.WriteLine((err ? "ERROR " : "") + msg);
+                    if (!PrintMode.HasFlag(mode)) return;
+                    if (err)
+                        _log.Error(msg);
+                    else
+                        _log.Info(msg);
+                }
+
+                if (PrintMsil || DumpTarget != null)
                 {
                     lock (_log)
                     {
-                    MethodTranspiler.IntegrityAnalysis(LogLevel.Info, il);
+                        var ctx = new MethodContext(_method);
+                        ctx.Read();
+                        LogTarget(PrintModeEnum.Original, false, "========== Original method ==========");
+                        MethodTranspiler.IntegrityAnalysis((a, b) => LogTarget(PrintModeEnum.Original, a, b), ctx.Instructions, true);
+                        LogTarget(PrintModeEnum.Original, false, gap);
+
+                        LogTarget(PrintModeEnum.Emitted, false, "========== Desired method ==========");
+                        MethodTranspiler.IntegrityAnalysis((a, b) => LogTarget(PrintModeEnum.Emitted, a, b), il);
+                        LogTarget(PrintModeEnum.Emitted, false, gap);
                     }
                 }
 
@@ -130,12 +188,29 @@ namespace Torch.Managers.PatchManager
                     {
                         var ctx = new MethodContext(method);
                         ctx.Read();
-                    MethodTranspiler.IntegrityAnalysis(LogLevel.Warn, ctx.Instructions);
+                        MethodTranspiler.IntegrityAnalysis((err, msg) => _log.Warn(msg), ctx.Instructions);
                     }
 
                     throw;
                 }
 
+                if (PrintMsil || DumpTarget != null)
+                {
+                    lock (_log)
+                    {
+                        var ctx = new MethodContext(method);
+                        ctx.Read();
+                        LogTarget(PrintModeEnum.Patched, false, "========== Patched method ==========");
+                        MethodTranspiler.IntegrityAnalysis((a, b) => LogTarget(PrintModeEnum.Patched, a, b), ctx.Instructions, true);
+                        LogTarget(PrintModeEnum.Patched, false, gap);
+                    }
+                }
+            }
+            finally
+            {
+                dumpTarget?.Close();
+            }
+
             return method;
         }
 
@@ -274,7 +349,8 @@ namespace Torch.Managers.PatchManager
                             ? param.ParameterType.GetElementType()
                             : param.ParameterType;
                         if (retType == null || !retType.IsAssignableFrom(specialVariables[RESULT_PARAMETER].Type))
-                            throw new Exception($"Return type {specialVariables[RESULT_PARAMETER].Type} can't be assigned to result parameter type {retType}");
+                            throw new Exception(
+                                $"Return type {specialVariables[RESULT_PARAMETER].Type} can't be assigned to result parameter type {retType}");
                         yield return new MsilInstruction(param.ParameterType.IsByRef ? OpCodes.Ldloca : OpCodes.Ldloc)
                             .InlineValue(specialVariables[RESULT_PARAMETER]);
                         break;

Torch/Managers/PatchManager/MSIL/MsilInstruction.cs

@@ -2,9 +2,11 @@
 using System.Collections.Concurrent;
 using System.Collections.Generic;
 using System.Diagnostics;
+using System.Linq;
 using System.Reflection;
 using System.Reflection.Emit;
 using System.Text;
+using System.Windows.Documents;
 using Torch.Managers.PatchManager.Transpile;
 using Torch.Utils;
 
@@ -103,8 +105,21 @@ namespace Torch.Managers.PatchManager.MSIL
         /// <summary>
         /// The try catch operation that is performed here.
         /// </summary>
-        public MsilTryCatchOperation TryCatchOperation { get; set; } = null;
+        [Obsolete("Since instructions can have multiple try catch operations you need to be using TryCatchOperations")]
+        public MsilTryCatchOperation TryCatchOperation
+        {
+            get => TryCatchOperations.FirstOrDefault();
+            set
+            {
+                TryCatchOperations.Clear();
+                TryCatchOperations.Add(value);
+            }
+        }
 
+        /// <summary>
+        /// The try catch operations performed here, in order from first to last.
+        /// </summary>
+        public readonly List<MsilTryCatchOperation> TryCatchOperations = new List<MsilTryCatchOperation>();
 
         private static readonly ConcurrentDictionary<Type, PropertyInfo> _setterInfoForInlines = new ConcurrentDictionary<Type, PropertyInfo>();
 
@@ -125,14 +140,17 @@ namespace Torch.Managers.PatchManager.MSIL
                     target = genType.GetProperty(nameof(MsilOperandInline<int>.Value));
                     _setterInfoForInlines[type] = target;
                 }
+
                 Debug.Assert(target?.DeclaringType != null);
                 if (target.DeclaringType.IsInstanceOfType(Operand))
                 {
                     target.SetValue(Operand, o);
                     return this;
                 }
+
                 type = type.BaseType;
             }
+
             ((MsilOperandInline<T>) Operand).Value = o;
             return this;
         }
@@ -148,7 +166,8 @@ namespace Torch.Managers.PatchManager.MSIL
             Operand?.CopyTo(result.Operand);
             foreach (MsilLabel x in Labels)
                 result.Labels.Add(x);
-            result.TryCatchOperation = TryCatchOperation;
+            foreach (var op in TryCatchOperations)
+                result.TryCatchOperations.Add(op);
             return result;
         }
 
@@ -185,7 +204,6 @@ namespace Torch.Managers.PatchManager.MSIL
         }
 
 
-
 #pragma warning disable 649
         [ReflectedMethod(Name = "StackChange")]
         private static Func<OpCode, int> _stackChange;
@@ -210,7 +228,13 @@ namespace Torch.Managers.PatchManager.MSIL
                 if (!op.IsStatic && OpCode != OpCodes.Newobj)
                     num--;
             }
+
             return num;
         }
+
+        /// <summary>
+        /// Gets the maximum amount of space this instruction will use.
+        /// </summary>
+        public int MaxBytes => 2 + (Operand?.MaxBytes ?? 0);
     }
 }

Torch/Managers/PatchManager/MSIL/MsilOperand.cs

@@ -18,6 +18,11 @@ namespace Torch.Managers.PatchManager.MSIL
         /// </summary>
         public MsilInstruction Instruction { get; }
 
+        /// <summary>
+        /// Gets the maximum amount of space this operand will use.
+        /// </summary>
+        public abstract int MaxBytes { get; }
+
         internal abstract void CopyTo(MsilOperand operand);
 
         internal abstract void Read(MethodContext context, BinaryReader reader);

Torch/Managers/PatchManager/MSIL/MsilOperandBrTarget.cs

@@ -57,6 +57,8 @@ namespace Torch.Managers.PatchManager.MSIL
 
         }
 
+        public override int MaxBytes => 4; // Long branch
+
         internal override void CopyTo(MsilOperand operand)
         {
             var lt = operand as MsilOperandBrTarget;

Torch/Managers/PatchManager/MSIL/MsilOperandInline.cs

@@ -54,6 +54,8 @@ namespace Torch.Managers.PatchManager.MSIL
             {
             }
 
+            public override int MaxBytes => Instruction.OpCode.OperandType == OperandType.InlineI ? 4 : 1;
+
             internal override void Read(MethodContext context, BinaryReader reader)
             {
                 // ReSharper disable once SwitchStatementMissingSomeCases
@@ -98,6 +100,8 @@ namespace Torch.Managers.PatchManager.MSIL
             {
             }
 
+            public override int MaxBytes => 4;
+
             internal override void Read(MethodContext context, BinaryReader reader)
             {
                 // ReSharper disable once SwitchStatementMissingSomeCases
@@ -136,6 +140,8 @@ namespace Torch.Managers.PatchManager.MSIL
             {
             }
 
+            public override int MaxBytes => 8;
+
             internal override void Read(MethodContext context, BinaryReader reader)
             {
                 // ReSharper disable once SwitchStatementMissingSomeCases
@@ -174,6 +180,8 @@ namespace Torch.Managers.PatchManager.MSIL
             {
             }
 
+            public override int MaxBytes => 8;
+
             internal override void Read(MethodContext context, BinaryReader reader)
             {
                 // ReSharper disable once SwitchStatementMissingSomeCases
@@ -212,6 +220,8 @@ namespace Torch.Managers.PatchManager.MSIL
             {
             }
 
+            public override int MaxBytes => 4;
+
             internal override void Read(MethodContext context, BinaryReader reader)
             {
                 // ReSharper disable once SwitchStatementMissingSomeCases
@@ -250,6 +260,8 @@ namespace Torch.Managers.PatchManager.MSIL
             {
             }
 
+            public override int MaxBytes => throw new NotImplementedException();
+
             internal override void Read(MethodContext context, BinaryReader reader)
             {
                 // ReSharper disable once SwitchStatementMissingSomeCases
@@ -286,6 +298,8 @@ namespace Torch.Managers.PatchManager.MSIL
             {
             }
 
+            public override int MaxBytes => Instruction.OpCode.OperandType == OperandType.ShortInlineVar ? 1 : 2;
+
             internal override void Read(MethodContext context, BinaryReader reader)
             {
                 int id;
@@ -339,6 +353,8 @@ namespace Torch.Managers.PatchManager.MSIL
             {
             }
 
+            public override int MaxBytes => 2;
+
             internal override void Read(MethodContext context, BinaryReader reader)
             {
                 int id;
@@ -390,6 +406,8 @@ namespace Torch.Managers.PatchManager.MSIL
             {
             }
             
+            public override int MaxBytes => 4;
+
             internal override void Read(MethodContext context, BinaryReader reader)
             {
                 object value = null;

Torch/Managers/PatchManager/MSIL/MsilOperandSwitch.cs

@@ -20,6 +20,7 @@ namespace Torch.Managers.PatchManager.MSIL
         /// </summary>
         public MsilLabel[] Labels { get; set; }
 
+        public override int MaxBytes => 4 + (Labels?.Length * 4 ?? 0);
 
         internal override void CopyTo(MsilOperand operand)
         {

Torch/Managers/PatchManager/MSIL/MsilTryCatchOperation.cs

@@ -24,6 +24,8 @@ namespace Torch.Managers.PatchManager.MSIL
     /// </summary>
     public class MsilTryCatchOperation
     {
+        internal int NativeOffset;
+        
         /// <summary>
         /// Operation type
         /// </summary>

Torch/Managers/PatchManager/MethodRewritePattern.cs

@@ -168,18 +168,71 @@ namespace Torch.Managers.PatchManager
         /// <summary>
         /// Should the resulting MSIL of the transpile operation be printed.
         /// </summary>
+        [Obsolete]
         public bool PrintMsil
         {
-            get => _parent?.PrintMsil ?? _printMsilBacking;
+            get => PrintMode != 0;
+            set => PrintMode = PrintModeEnum.Emitted;
+        }
+        
+        private PrintModeEnum _printMsilBacking;
+        
+        /// <summary>
+        /// Types of IL to print to log
+        /// </summary>
+        public PrintModeEnum PrintMode
+        {
+            get => _parent?.PrintMode ?? _printMsilBacking;
             set
             {
                 if (_parent != null)
-                    _parent.PrintMsil = value;
+                    _parent.PrintMode = value;
                 else
                     _printMsilBacking = value;
             }
         }
-        private bool _printMsilBacking;
+
+        [Flags]
+        public enum PrintModeEnum
+        {
+            Original = 1,
+            Emitted = 2,
+            Patched = 4,
+            EmittedReflection = 8
+        }
+        
+        /// <summary>
+        /// File to dump the emitted MSIL to.
+        /// </summary>
+        public string DumpTarget
+        {
+            get => _parent?.DumpTarget ?? _dumpTargetBacking;
+            set
+            {
+                if (_parent != null)
+                    _parent.DumpTarget = value;
+                else
+                    _dumpTargetBacking = value;
+            }
+        }
+        
+        /// <summary>
+        /// Types of IL to dump to file
+        /// </summary>
+        public PrintModeEnum DumpMode
+        {
+            get => _parent?.DumpMode ?? _dumpTargetMode;
+            set
+            {
+                if (_parent != null)
+                    _parent.DumpMode = value;
+                else
+                    _dumpTargetMode = value;
+            }
+        }
+
+        private PrintModeEnum _dumpTargetMode;
+        private string _dumpTargetBacking;
 
         private readonly MethodRewritePattern _parent;
 

Torch/Managers/PatchManager/PatchUtilities.cs

@@ -40,21 +40,25 @@ namespace Torch.Managers.PatchManager
             MethodTranspiler.EmitMethod(insn.ToList(), generator);
         }
 
+        public delegate void DelPrintIntegrityInfo(bool error, string msg);
+
         /// <summary>
         /// Analyzes the integrity of a set of instructions.
         /// </summary>
-        /// <param name="level">default logging level</param>
+        /// <param name="handler">Logger</param>
         /// <param name="instructions">instructions</param>
-        public static void IntegrityAnalysis(LogLevel level, IReadOnlyList<MsilInstruction> instructions)
+        public static void IntegrityAnalysis(DelPrintIntegrityInfo handler, IReadOnlyList<MsilInstruction> instructions)
         {
-            MethodTranspiler.IntegrityAnalysis(level, instructions);
+            MethodTranspiler.IntegrityAnalysis(handler, instructions);
         }
 
 #pragma warning disable 649
         [ReflectedStaticMethod(Type = typeof(RuntimeHelpers), Name = "_CompileMethod", OverrideTypeNames = new[] {"System.IRuntimeMethodInfo"})]
         private static Action<object> _compileDynamicMethod;
+
         [ReflectedMethod(Name = "GetMethodInfo")]
         private static Func<RuntimeMethodHandle, object> _getMethodInfo;
+
         [ReflectedMethod(Name = "GetMethodDescriptor")]
         private static Func<DynamicMethod, RuntimeMethodHandle> _getMethodHandle;
 #pragma warning restore 649

Torch/Managers/PatchManager/Transpile/MethodContext.cs

@@ -8,6 +8,7 @@ using System.Reflection.Emit;
 using NLog;
 using Torch.Managers.PatchManager.MSIL;
 using Torch.Utils;
+using VRage.Game.VisualScripting.Utils;
 
 namespace Torch.Managers.PatchManager.Transpile
 {
@@ -44,14 +45,47 @@ namespace Torch.Managers.PatchManager.Transpile
 
 
 #pragma warning disable 649
-        [ReflectedMethod(Name = "BakeByteArray")] private static Func<ILGenerator, byte[]> _ilGeneratorBakeByteArray;
+        [ReflectedMethod(Name = "BakeByteArray")]
+        private static Func<ILGenerator, byte[]> _ilGeneratorBakeByteArray;
+
+        [ReflectedMethod(Name = "GetExceptions")]
+        private static Func<ILGenerator, Array> _ilGeneratorGetExceptionHandlers;
+
+        private const string InternalExceptionInfo = "System.Reflection.Emit.__ExceptionInfo, mscorlib";
+
+        [ReflectedMethod(Name = "GetExceptionTypes", TypeName = InternalExceptionInfo)]
+        private static Func<object, int[]> _exceptionHandlerGetTypes;
+
+        [ReflectedMethod(Name = "GetStartAddress", TypeName = InternalExceptionInfo)]
+        private static Func<object, int> _exceptionHandlerGetStart;
+
+        [ReflectedMethod(Name = "GetEndAddress", TypeName = InternalExceptionInfo)]
+        private static Func<object, int> _exceptionHandlerGetEnd;
+
+        [ReflectedMethod(Name = "GetFinallyEndAddress", TypeName = InternalExceptionInfo)]
+        private static Func<object, int> _exceptionHandlerGetFinallyEnd;
+
+        [ReflectedMethod(Name = "GetNumberOfCatches", TypeName = InternalExceptionInfo)]
+        private static Func<object, int> _exceptionHandlerGetCatchCount;
+
+        [ReflectedMethod(Name = "GetCatchAddresses", TypeName = InternalExceptionInfo)]
+        private static Func<object, int[]> _exceptionHandlerGetCatchAddrs;
+
+        [ReflectedMethod(Name = "GetCatchEndAddresses", TypeName = InternalExceptionInfo)]
+        private static Func<object, int[]> _exceptionHandlerGetCatchEndAddrs;
+
+        [ReflectedMethod(Name = "GetFilterAddresses", TypeName = InternalExceptionInfo)]
+        private static Func<object, int[]> _exceptionHandlerGetFilterAddrs;
 #pragma warning restore 649
 
+        private readonly Array _dynamicExceptionTable;
+
         public MethodContext(DynamicMethod method)
         {
             Method = null;
             MethodBody = null;
             _msilBytes = _ilGeneratorBakeByteArray(method.GetILGenerator());
+            _dynamicExceptionTable = _ilGeneratorGetExceptionHandlers(method.GetILGenerator());
             TokenResolver = new DynamicMethodTokenResolver(method);
         }
 
@@ -76,6 +110,7 @@ namespace Torch.Managers.PatchManager.Transpile
                     {
                         instructionValue = (short) ((instructionValue << 8) | memory.ReadByte());
                     }
+
                     if (!OpCodeLookup.TryGetValue(instructionValue, out OpCode opcode))
                     {
                         var msg = $"Unknown opcode {instructionValue:X}";
@@ -83,6 +118,7 @@ namespace Torch.Managers.PatchManager.Transpile
                         Debug.Assert(false, msg);
                         continue;
                     }
+
                     if (opcode.Size != memory.Position - opcodeOffset)
                         throw new Exception(
                             $"Opcode said it was {opcode.Size} but we read {memory.Position - opcodeOffset}");
@@ -97,28 +133,56 @@ namespace Torch.Managers.PatchManager.Transpile
 
         private void ResolveCatchClauses()
         {
-            if (MethodBody == null)
-                return;
-            foreach (ExceptionHandlingClause clause in MethodBody.ExceptionHandlingClauses)
+            if (MethodBody != null)
+                foreach (var clause in MethodBody.ExceptionHandlingClauses)
                 {
-                var beginInstruction = FindInstruction(clause.TryOffset);
-                var catchInstruction = FindInstruction(clause.HandlerOffset);
-                var finalInstruction = FindInstruction(clause.HandlerOffset + clause.HandlerLength);
-                beginInstruction.TryCatchOperation =
-                    new MsilTryCatchOperation(MsilTryCatchOperationType.BeginExceptionBlock);
+                    AddEhHandler(clause.TryOffset, MsilTryCatchOperationType.BeginExceptionBlock);
                     if ((clause.Flags & ExceptionHandlingClauseOptions.Fault) != 0)
-                    catchInstruction.TryCatchOperation =
-                        new MsilTryCatchOperation(MsilTryCatchOperationType.BeginFaultBlock);
+                        AddEhHandler(clause.HandlerOffset, MsilTryCatchOperationType.BeginFaultBlock);
                     else if ((clause.Flags & ExceptionHandlingClauseOptions.Finally) != 0)
-                    catchInstruction.TryCatchOperation =
-                        new MsilTryCatchOperation(MsilTryCatchOperationType.BeginFinallyBlock);
+                        AddEhHandler(clause.HandlerOffset, MsilTryCatchOperationType.BeginFinallyBlock);
                     else
-                    catchInstruction.TryCatchOperation =
-                        new MsilTryCatchOperation(MsilTryCatchOperationType.BeginClauseBlock, clause.CatchType);
-
-                finalInstruction.TryCatchOperation =
-                    new MsilTryCatchOperation(MsilTryCatchOperationType.EndExceptionBlock);
+                        AddEhHandler(clause.HandlerOffset, MsilTryCatchOperationType.BeginClauseBlock, clause.CatchType);
+                    AddEhHandler(clause.HandlerOffset + clause.HandlerLength, MsilTryCatchOperationType.EndExceptionBlock);
                 }
+
+            if (_dynamicExceptionTable != null)
+                foreach (var eh in _dynamicExceptionTable)
+                {
+                    var catchCount = _exceptionHandlerGetCatchCount(eh);
+                    var exTypes = _exceptionHandlerGetTypes(eh);
+                    var exCatches = _exceptionHandlerGetCatchAddrs(eh);
+                    var exCatchesEnd = _exceptionHandlerGetCatchEndAddrs(eh);
+                    var exFilters = _exceptionHandlerGetFilterAddrs(eh);
+                    var tryAddr = _exceptionHandlerGetStart(eh);
+                    var endAddr = _exceptionHandlerGetEnd(eh);
+                    var endFinallyAddr = _exceptionHandlerGetFinallyEnd(eh);
+                    for (var i = 0; i < catchCount; i++)
+                    {
+                        var flags = (ExceptionHandlingClauseOptions) exTypes[i];
+                        var endAddress = (flags & ExceptionHandlingClauseOptions.Finally) != 0 ? endFinallyAddr : endAddr;
+
+                        var catchAddr = exCatches[i];
+                        var catchEndAddr = exCatchesEnd[i];
+                        var filterAddr = exFilters[i];
+                        
+                        AddEhHandler(tryAddr, MsilTryCatchOperationType.BeginExceptionBlock);
+                        if ((flags & ExceptionHandlingClauseOptions.Fault) != 0)
+                            AddEhHandler(catchAddr, MsilTryCatchOperationType.BeginFaultBlock);
+                        else if ((flags & ExceptionHandlingClauseOptions.Finally) != 0)
+                            AddEhHandler(catchAddr, MsilTryCatchOperationType.BeginFinallyBlock);
+                        else
+                            AddEhHandler(catchAddr, MsilTryCatchOperationType.BeginClauseBlock);
+                        AddEhHandler(catchEndAddr, MsilTryCatchOperationType.EndExceptionBlock);
+                    }
+                }
+        }
+
+        private void AddEhHandler(int offset, MsilTryCatchOperationType op, Type type = null)
+        {
+            var instruction = FindInstruction(offset);
+            instruction.TryCatchOperations.Add(new MsilTryCatchOperation(op, type) {NativeOffset = offset});
+            instruction.TryCatchOperations.Sort((a, b) => a.NativeOffset.CompareTo(b.NativeOffset));
         }
 
         public MsilInstruction FindInstruction(int offset)
@@ -132,6 +196,7 @@ namespace Torch.Managers.PatchManager.Transpile
                 else
                     max = mid;
             }
+
             return min >= 0 && min < _instructions.Count ? _instructions[min] : null;
         }
 

Torch/Managers/PatchManager/Transpile/MethodTranspiler.cs

@@ -14,8 +14,8 @@ namespace Torch.Managers.PatchManager.Transpile
     {
         public static readonly Logger _log = LogManager.GetCurrentClassLogger();
 
-        internal static IEnumerable<MsilInstruction> Transpile(MethodBase baseMethod, Func<Type, MsilLocal> localCreator,
-            IEnumerable<MethodInfo> transpilers, MsilLabel retLabel)
+        internal static IEnumerable<MsilInstruction> Transpile(MethodBase baseMethod, Func<Type, MsilLocal> localCreator, IEnumerable<MethodInfo> transpilers,
+            MsilLabel retLabel)
         {
             var context = new MethodContext(baseMethod);
             context.Read();
@@ -24,8 +24,7 @@ namespace Torch.Managers.PatchManager.Transpile
         }
 
         internal static IEnumerable<MsilInstruction> Transpile(MethodBase baseMethod, IEnumerable<MsilInstruction> methodContent,
-            Func<Type, MsilLocal> localCreator,
-            IEnumerable<MethodInfo> transpilers, MsilLabel retLabel)
+            Func<Type, MsilLocal> localCreator, IEnumerable<MethodInfo> transpilers, MsilLabel retLabel)
         {
             foreach (MethodInfo transpiler in transpilers)
             {
@@ -44,24 +43,61 @@ namespace Torch.Managers.PatchManager.Transpile
                         throw new ArgumentException(
                             $"Bad transpiler parameter type {parameter.ParameterType.FullName} {parameter.Name}");
                 }
+
                 methodContent = (IEnumerable<MsilInstruction>) transpiler.Invoke(null, paramList.ToArray());
             }
+
             return FixBranchAndReturn(methodContent, retLabel);
         }
 
-        internal static void EmitMethod(IReadOnlyList<MsilInstruction> instructions, LoggingIlGenerator target)
+        internal static void EmitMethod(IReadOnlyList<MsilInstruction> source, LoggingIlGenerator target)
         {
-            for (var i = 0; i < instructions.Count; i++)
+            var instructions = source.ToArray();
+            var offsets = new int[instructions.Length];
+            // Calc worst case offsets
+            {
+                var j = 0;
+                for (var i = 0; i < instructions.Length; i++)
+                {
+                    offsets[i] = j;
+                    j += instructions[i].MaxBytes;
+                }
+            }
+
+            // Perform label markup
+            var targets = new Dictionary<MsilLabel, int>();
+            for (var i = 0; i < instructions.Length; i++)
+                foreach (var label in instructions[i].Labels)
+                {
+                    if (targets.TryGetValue(label, out var other))
+                        _log.Warn($"Label {label} is applied to ({i}: {instructions[i]}) and ({other}: {instructions[other]})");
+                    targets[label] = i;
+                }
+
+            // Simplify branch instructions
+            for (var i = 0; i < instructions.Length; i++)
+            {
+                var existing = instructions[i];
+                if (existing.Operand is MsilOperandBrTarget brOperand && _longToShortBranch.TryGetValue(existing.OpCode, out var shortOpcode))
+                {
+                    var targetIndex = targets[brOperand.Target];
+                    var delta = offsets[targetIndex] - offsets[i];
+                    if (sbyte.MinValue < delta && delta < sbyte.MaxValue)
+                        instructions[i] = instructions[i].CopyWith(shortOpcode);
+                }
+            }
+
+            for (var i = 0; i < instructions.Length; i++)
             {
                 MsilInstruction il = instructions[i];
-                if (il.TryCatchOperation != null)
-                    switch (il.TryCatchOperation.Type)
+                foreach (var tro in il.TryCatchOperations)
+                    switch (tro.Type)
                     {
                         case MsilTryCatchOperationType.BeginExceptionBlock:
                             target.BeginExceptionBlock();
                             break;
                         case MsilTryCatchOperationType.BeginClauseBlock:
-                            target.BeginCatchBlock(il.TryCatchOperation.CatchType);
+                            target.BeginCatchBlock(tro.CatchType);
                             break;
                         case MsilTryCatchOperationType.BeginFaultBlock:
                             target.BeginFaultBlock();
@@ -79,20 +115,23 @@ namespace Torch.Managers.PatchManager.Transpile
                 foreach (MsilLabel label in il.Labels)
                     target.MarkLabel(label.LabelFor(target));
 
-                MsilInstruction ilNext = i < instructions.Count - 1 ? instructions[i + 1] : null;
+                MsilInstruction ilNext = i < instructions.Length - 1 ? instructions[i + 1] : null;
 
                 // Leave opcodes emitted by these:
-                if (il.OpCode == OpCodes.Endfilter && ilNext?.TryCatchOperation?.Type ==
-                    MsilTryCatchOperationType.BeginClauseBlock)
+                if (il.OpCode == OpCodes.Endfilter && ilNext != null &&
+                    ilNext.TryCatchOperations.Any(x => x.Type == MsilTryCatchOperationType.BeginClauseBlock))
                     continue;
-                if ((il.OpCode == OpCodes.Leave || il.OpCode == OpCodes.Leave_S) &&
-                    (ilNext?.TryCatchOperation?.Type == MsilTryCatchOperationType.EndExceptionBlock ||
-                     ilNext?.TryCatchOperation?.Type == MsilTryCatchOperationType.BeginClauseBlock ||
-                     ilNext?.TryCatchOperation?.Type == MsilTryCatchOperationType.BeginFaultBlock ||
-                     ilNext?.TryCatchOperation?.Type == MsilTryCatchOperationType.BeginFinallyBlock))
+                if ((il.OpCode == OpCodes.Leave || il.OpCode == OpCodes.Leave_S) && ilNext != null &&
+                    ilNext.TryCatchOperations.Any(x => x.Type == MsilTryCatchOperationType.EndExceptionBlock ||
+                                                       x.Type == MsilTryCatchOperationType.BeginClauseBlock ||
+                                                       x.Type == MsilTryCatchOperationType.BeginFaultBlock ||
+                                                       x.Type == MsilTryCatchOperationType.BeginFinallyBlock))
                     continue;
                 if ((il.OpCode == OpCodes.Leave || il.OpCode == OpCodes.Leave_S || il.OpCode == OpCodes.Endfinally) &&
-                    ilNext?.TryCatchOperation?.Type == MsilTryCatchOperationType.EndExceptionBlock)
+                    ilNext != null && ilNext.TryCatchOperations.Any(x => x.Type == MsilTryCatchOperationType.EndExceptionBlock))
+                    continue;
+                if (il.OpCode == OpCodes.Endfinally && ilNext != null &&
+                    ilNext.TryCatchOperations.Any(x => x.Type == MsilTryCatchOperationType.EndExceptionBlock))
                     continue;
 
                 if (il.Operand != null)
@@ -107,7 +146,7 @@ namespace Torch.Managers.PatchManager.Transpile
         /// </summary>
         /// <param name="level">default logging level</param>
         /// <param name="instructions">instructions</param>
-        public static void IntegrityAnalysis(LogLevel level, IReadOnlyList<MsilInstruction> instructions)
+        public static void IntegrityAnalysis(PatchUtilities.DelPrintIntegrityInfo log, IReadOnlyList<MsilInstruction> instructions, bool offests = false)
         {
             var targets = new Dictionary<MsilLabel, int>();
             for (var i = 0; i < instructions.Count; i++)
@@ -118,15 +157,46 @@ namespace Torch.Managers.PatchManager.Transpile
                     targets[label] = i;
                 }
 
+            var simpleLabelNames = new Dictionary<MsilLabel, string>();
+            foreach (var lbl in targets.OrderBy(x => x.Value))
+                simpleLabelNames.Add(lbl.Key, "L" + simpleLabelNames.Count);
+
             var reparsed = new HashSet<MsilLabel>();
             var labelStackSize = new Dictionary<MsilLabel, Dictionary<int, int>>();
             var stack = 0;
             var unreachable = false;
             var data = new StringBuilder[instructions.Count];
-            for (var i = 0; i < instructions.Count; i++)
+            var tryCatchDepth = new int[instructions.Count];
+
+            for (var i = 0; i < instructions.Count - 1; i++)
             {
+                var k = instructions[i];
+                var prevDepth = i > 0 ? tryCatchDepth[i] : 0;
+                var currentDepth = prevDepth;
+                foreach (var tro in k.TryCatchOperations)
+                    if (tro.Type == MsilTryCatchOperationType.BeginExceptionBlock)
+                        currentDepth++;
+                    else if (tro.Type == MsilTryCatchOperationType.EndExceptionBlock)
+                        currentDepth--;
+                tryCatchDepth[i + 1] = currentDepth;
+            }
+
+            for (var i = 0; i < instructions.Count; i++)
+            {
+                var tryCatchDepthSelf = tryCatchDepth[i];
                 var k = instructions[i];
                 var line = (data[i] ?? (data[i] = new StringBuilder())).Clear();
+                foreach (var tro in k.TryCatchOperations)
+                {
+                    if (tro.Type == MsilTryCatchOperationType.BeginExceptionBlock)
+                        tryCatchDepthSelf++;
+                    line.AppendLine($"{new string(' ', (tryCatchDepthSelf - 1) * 2)}// {tro.Type} ({tro.CatchType}) ({tro.NativeOffset:X4})");
+                    if (tro.Type == MsilTryCatchOperationType.EndExceptionBlock)
+                        tryCatchDepthSelf--;
+                }
+
+                var tryCatchIndent = new string(' ', tryCatchDepthSelf * 2);
+
                 if (!unreachable)
                 {
                     foreach (var label in k.Labels)
@@ -138,59 +208,83 @@ namespace Torch.Managers.PatchManager.Transpile
                         if (otherStack.Values.Distinct().Count() > 1 || (otherStack.Count == 1 && !otherStack.ContainsValue(stack)))
                         {
                             string otherDesc = string.Join(", ", otherStack.Select(x => $"{x.Key:X4}=>{x.Value}"));
-                            line.AppendLine($"WARN// | Label {label} has multiple entry stack sizes ({otherDesc})");
+                            line.AppendLine($"WARN{tryCatchIndent}// | Label {simpleLabelNames[label]} has multiple entry stack sizes ({otherDesc})");
                         }
                     }
                 }
+
                 foreach (var label in k.Labels)
                 {
                     if (!labelStackSize.TryGetValue(label, out var entry))
+                    {
+                        line.AppendLine($"{tryCatchIndent}// \\/ Label {simpleLabelNames[label]}");
                         continue;
+                    }
                     string desc = string.Join(", ", entry.Select(x => $"{x.Key:X4}=>{x.Value}"));
-                    line.AppendLine($"// \\/ Label {label} has stack sizes {desc}");
+                    line.AppendLine($"{tryCatchIndent}// \\/ Label {simpleLabelNames[label]} has stack sizes {desc}");
                     if (unreachable && entry.Any())
                     {
                         stack = entry.Values.First();
                         unreachable = false;
                     }
                 }
-                stack += k.StackChange();
-                if (k.TryCatchOperation != null)
-                    line.AppendLine($"// .{k.TryCatchOperation.Type} ({k.TryCatchOperation.CatchType})");
-                line.AppendLine($"{i:X4} S:{stack:D2} dS:{k.StackChange():+0;-#}\t{k}" + (unreachable ? "\t// UNREACHABLE" : ""));
-                if (k.Operand is MsilOperandBrTarget br)
-                {
-                    if (!targets.ContainsKey(br.Target))
-                        line.AppendLine($"WARN// ^ Unknown target {br.Target}");
 
-                    if (!labelStackSize.TryGetValue(br.Target, out Dictionary<int, int> otherStack))
-                        labelStackSize[br.Target] = otherStack = new Dictionary<int, int>();
+                if (k.TryCatchOperations.Any(x => x.Type == MsilTryCatchOperationType.BeginClauseBlock))
+                    stack++; // Exception info
+                stack += k.StackChange();
+                line.Append($"{tryCatchIndent}{(offests ? k.Offset : i):X4} S:{stack:D2} dS:{k.StackChange():+0;-#}\t{k.OpCode}\t");
+                if (k.Operand is MsilOperandBrTarget bri)
+                    line.Append(simpleLabelNames[bri.Target]);
+                else
+                    line.Append(k.Operand);
+                line.AppendLine($"\t{(unreachable ? "\t// UNREACHABLE" : "")}");
+                MsilLabel[] branchTargets = null;
+                if (k.Operand is MsilOperandBrTarget br)
+                    branchTargets = new[] {br.Target};
+                else if (k.Operand is MsilOperandSwitch swi)
+                    branchTargets = swi.Labels;
+
+                if (branchTargets != null)
+                {
+                    var foundUnprocessed = false;
+                    foreach (var brTarget in branchTargets)
+                    {
+                        if (!labelStackSize.TryGetValue(brTarget, out Dictionary<int, int> otherStack))
+                            labelStackSize[brTarget] = otherStack = new Dictionary<int, int>();
 
                         otherStack[i] = stack;
                         if (otherStack.Values.Distinct().Count() > 1 || (otherStack.Count == 1 && !otherStack.ContainsValue(stack)))
                         {
                             string otherDesc = string.Join(", ", otherStack.Select(x => $"{x.Key:X4}=>{x.Value}"));
-                        line.AppendLine($"WARN// ^ Label {br.Target} has multiple entry stack sizes ({otherDesc})");
+                            line.AppendLine($"WARN{tryCatchIndent}// ^ Label {simpleLabelNames[brTarget]} has multiple entry stack sizes ({otherDesc})");
                         }
-                    if (targets.TryGetValue(br.Target, out var target) && target < i && reparsed.Add(br.Target))
+
+                        if (targets.TryGetValue(brTarget, out var target) && target < i && reparsed.Add(brTarget))
                         {
                             i = target - 1;
                             unreachable = false;
+                            foundUnprocessed = true;
+                            break;
+                        }
+                    }
+
+                    if (foundUnprocessed)
                         continue;
                 }
-                }
+
                 if (k.OpCode == OpCodes.Br || k.OpCode == OpCodes.Br_S || k.OpCode == OpCodes.Leave || k.OpCode == OpCodes.Leave_S)
                     unreachable = true;
             }
+
             foreach (var k in data)
             foreach (var line in k.ToString().Split('\n'))
             {
                 if (string.IsNullOrWhiteSpace(line))
                     continue;
                 if (line.StartsWith("WARN", StringComparison.OrdinalIgnoreCase))
-                        _log.Warn(line.Substring(4).Trim());
+                    log(true, line.Substring(4).Trim());
                 else
-                        _log.Log(level, line.Trim());
+                    log(false, line.Trim('\n', '\r'));
             }
         }
 
@@ -204,7 +298,7 @@ namespace Torch.Managers.PatchManager.Transpile
                     _log.Trace($"Replacing {i} with {j}");
                     yield return j;
                 }
-                else if (_opcodeReplaceRule.TryGetValue(i.OpCode, out OpCode replaceOpcode))
+                else if (_shortToLongBranch.TryGetValue(i.OpCode, out OpCode replaceOpcode))
                 {
                     var result = i.CopyWith(replaceOpcode);
                     _log.Trace($"Replacing {i} with {result}");
@@ -215,10 +309,13 @@ namespace Torch.Managers.PatchManager.Transpile
             }
         }
 
-        private static readonly Dictionary<OpCode, OpCode> _opcodeReplaceRule;
+        private static readonly Dictionary<OpCode, OpCode> _shortToLongBranch;
+        private static readonly Dictionary<OpCode, OpCode> _longToShortBranch;
+
         static MethodTranspiler()
         {
-            _opcodeReplaceRule = new Dictionary<OpCode, OpCode>();
+            _shortToLongBranch = new Dictionary<OpCode, OpCode>();
+            _longToShortBranch = new Dictionary<OpCode, OpCode>();
             foreach (var field in typeof(OpCodes).GetFields(BindingFlags.Static | BindingFlags.Public))
             {
                 var opcode = (OpCode) field.GetValue(null);
@@ -228,10 +325,15 @@ namespace Torch.Managers.PatchManager.Transpile
                     var other = (OpCode?) typeof(OpCodes).GetField(field.Name.Substring(0, field.Name.Length - 2),
                         BindingFlags.Static | BindingFlags.Public)?.GetValue(null);
                     if (other.HasValue && other.Value.OperandType == OperandType.InlineBrTarget)
-                        _opcodeReplaceRule.Add(opcode, other.Value);
-                }
-            }
-            _opcodeReplaceRule[OpCodes.Leave_S] = OpCodes.Leave;
+                    {
+                        _shortToLongBranch.Add(opcode, other.Value);
+                        _longToShortBranch.Add(other.Value, opcode);
+                    }
+                }
+            }
+
+            _shortToLongBranch[OpCodes.Leave_S] = OpCodes.Leave;
+            _longToShortBranch[OpCodes.Leave] = OpCodes.Leave_S;
         }
     }
 }