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How to use IsAsyncStateMachineHandler method of Microsoft.Coyote.Rewriting.ExceptionFilterRewritingPass class

Best Coyote code snippet using Microsoft.Coyote.Rewriting.ExceptionFilterRewritingPass.IsAsyncStateMachineHandler

ExceptionFilterRewritingPass.cs

Source:ExceptionFilterRewritingPass.cs

...54        /// In the case of nested try/catch blocks the inner block is visited first before the outer block.55        /// </remarks>56        internal void VisitExceptionHandler(ExceptionHandler handler)57        {58            if ((this.IsAsyncStateMachineType && IsAsyncStateMachineHandler(handler)) ||59                IsRethrowHandler(handler))60            {61                // Do not instrument the compiler generated catch block of an async state machine,62                // or an exception handler that is just a rethrow.63                return;64            }65            if (handler.FilterStart is null)66            {67                if (handler.CatchType is null)68                {69                    // This is a finally block, which we can skip.70                    return;71                }72                var name = handler.CatchType.FullName;73                if (name == typeof(object).FullName ||74                    name == typeof(System.Exception).FullName ||75                    name == typeof(RuntimeException).FullName)76                {77                    this.AddThrowIfExecutionCanceledException(handler);78                }79            }80            else81            {82                // If there is an existing filter, then just insert a check.83                this.AddThrowIfExecutionCanceledException(handler);84            }85        }86        private void AddThrowIfExecutionCanceledException(ExceptionHandler handler)87        {88            if (!this.IsMethodBodyModified)89            {90                // A previous transform may have replaced some instructions, and if so, we need to recompute91                // the instruction indexes before we operate on the try catch.92                FixInstructionOffsets(this.Method);93                this.IsMethodBodyModified = true;94            }95            Debug.WriteLine($"............. [+] rewriting catch block to rethrow a {nameof(ThreadInterruptedException)}");96            var providerType = this.Method.Module.ImportReference(typeof(ExceptionProvider)).Resolve();97            MethodReference providerMethod = providerType.Methods.FirstOrDefault(98                m => m.Name is nameof(ExceptionProvider.ThrowIfThreadInterruptedException));99            providerMethod = this.Method.Module.ImportReference(providerMethod);100            var processor = this.Method.Body.GetILProcessor();101            var newStart = Instruction.Create(OpCodes.Dup);102            var previousStart = handler.HandlerStart;103            processor.InsertBefore(handler.HandlerStart, newStart);104            processor.InsertBefore(handler.HandlerStart, Instruction.Create(OpCodes.Call, providerMethod));105            handler.HandlerStart = newStart;106            // Fix up any other handler end position that points to previousStart instruction.107            foreach (var other in this.Method.Body.ExceptionHandlers)108            {109                // The first (or most nested) try/catch block.110                if (other.TryEnd == previousStart)111                {112                    other.TryEnd = newStart;113                }114                if (other.HandlerEnd == previousStart)115                {116                    other.HandlerEnd = newStart;117                }118            }119        }120        /// <summary>121        /// Checks if the specified handler is only rethrowing an exception.122        /// </summary>123        private static bool IsRethrowHandler(ExceptionHandler handler)124        {125            Code previousOpCode = Code.Nop;126            bool isRethrowing = false;127            Instruction instruction = handler.HandlerStart;128            while (instruction != handler.HandlerEnd)129            {130                Code opCode = instruction.OpCode.Code;131                if (opCode is Code.Throw || opCode is Code.Rethrow)132                {133                    isRethrowing = true;134                    break;135                }136                if (opCode != Code.Nop && opCode != Code.Pop)137                {138                    // TODO: optimize for generated async state machine cases.139                    if (previousOpCode != Code.Nop && !IsStoreLoadOpCodeMatching(previousOpCode, opCode))140                    {141                        break;142                    }143                    previousOpCode = opCode;144                }145                instruction = instruction.Next;146            }147            return isRethrowing;148        }149        /// <summary>150        /// Checks if the specified store and load op codes are matching.151        /// </summary>152        private static bool IsStoreLoadOpCodeMatching(Code storeCode, Code loadCode) =>153            storeCode is Code.Stloc_0 ? loadCode is Code.Ldloc_0 :154            storeCode is Code.Stloc_1 ? loadCode is Code.Ldloc_1 :155            storeCode is Code.Stloc_2 ? loadCode is Code.Ldloc_2 :156            storeCode is Code.Stloc_3 && loadCode is Code.Ldloc_3;157        /// <summary>158        /// Checks if the specified handler is generated for the async state machine.159        /// </summary>160        private static bool IsAsyncStateMachineHandler(ExceptionHandler handler)161        {162            Instruction instruction = handler.HandlerStart;163            while (instruction != handler.HandlerEnd)164            {165                if (instruction.Operand is MethodReference method)166                {167                    TypeReference type = method.DeclaringType;168                    if ((type.Namespace == typeof(Types.Runtime.CompilerServices.AsyncTaskMethodBuilder).Namespace ||169                        type.Namespace == NameCache.SystemCompilerNamespace) &&170                        ((type.Name == NameCache.AsyncTaskMethodBuilderName ||171                        type.Name.StartsWith("AsyncTaskMethodBuilder`")) ||172                        (type.Name == NameCache.AsyncValueTaskMethodBuilderName ||173                        type.Name.StartsWith("AsyncValueTaskMethodBuilder`"))) &&174                        (method.Name is nameof(SystemCompiler.AsyncTaskMethodBuilder.SetException) ||...

IsAsyncStateMachineHandler

Using AI Code Generation

1using System;2using System.Collections.Generic;3using System.Linq;4using System.Text;5using System.Threading.Tasks;6{7    {8        static void Main(string[] args)9        {10            Console.WriteLine("Hello World!");11            Console.ReadKey();12        }13    }14}15using System;16using System.Collections.Generic;17using System.Linq;18using System.Text;19using System.Threading.Tasks;20{21    {22        static void Main(string[] args)23        {24            Console.WriteLine("Hello World!");25            Console.ReadKey();26        }27    }28}29using System;30using System.Collections.Generic;31using System.Linq;32using System.Text;33using System.Threading.Tasks;34{35    {36        static void Main(string[] args)37        {38            Console.WriteLine("Hello World!");39            Console.ReadKey();40        }41    }42}43using System;44using System.Collections.Generic;45using System.Linq;46using System.Text;47using System.Threading.Tasks;48{49    {50        static void Main(string[] args)51        {52            Console.WriteLine("Hello World!");53            Console.ReadKey();54        }55    }56}57using System;58using System.Collections.Generic;59using System.Linq;60using System.Text;61using System.Threading.Tasks;62{63    {64        static void Main(string[] args)65        {66            Console.WriteLine("Hello World!");67            Console.ReadKey();68        }69    }70}71using System;72using System.Collections.Generic;73using System.Linq;74using System.Text;75using System.Threading.Tasks;76{77    {78        static void Main(string[] args)79        {80            Console.WriteLine("Hello World!");81            Console.ReadKey();82        }83    }84}

IsAsyncStateMachineHandler

Using AI Code Generation

1using Microsoft.Coyote.Rewriting;2using Microsoft.Coyote.Tasks;3using System;4using System.Threading.Tasks;5{6    {7        static void Main(string[] args)8        {9            Console.WriteLine("Hello World!");10            Program p = new Program();11            p.Test();12            Console.ReadLine();13        }14        async Task Test()15        {16            await Task.Delay(1000);17        }18    }19}20using Microsoft.Coyote.Rewriting;21using Microsoft.Coyote.Tasks;22using System;23using System.Threading.Tasks;24{25    {26        static void Main(string[] args)27        {28            Console.WriteLine("Hello World!");29            Program p = new Program();30            p.Test();31            Console.ReadLine();32        }33        async Task Test()34        {35            await Task.Delay(1000);36            throw new Exception();37        }38    }39}

IsAsyncStateMachineHandler

Using AI Code Generation

1using System;2using System.Collections.Generic;3using System.Linq;4using System.Text;5using System.Threading.Tasks;6using Microsoft.Coyote.Rewriting;7using System.Reflection;8using System.IO;9{10    {11        static void Main(string[] args)12        {13            string path = @"C:\Users\user\Documents\Visual Studio 2015\Projects\ConsoleApplication1\ConsoleApplication1\bin\Debug\ConsoleApplication1.exe";14            Assembly assembly = Assembly.LoadFrom(path);15            var types = assembly.GetTypes();16            foreach (var type in types)17            {18                var methods = type.GetMethods(BindingFlags.NonPublic | BindingFlags.Public | BindingFlags.Static | BindingFlags.Instance);19                foreach (var method in methods)20                {21                    if (ExceptionFilterRewritingPass.IsAsyncStateMachineHandler(method))22                    {23                        Console.WriteLine("Method {0} is an async state machine handler", method.Name);24                    }25                }26            }27            Console.ReadLine();28        }29    }30}31using System;32using System.Collections.Generic;33using System.Linq;34using System.Text;35using System.Threading.Tasks;36using Microsoft.Coyote.Rewriting;37using System.Reflection;38using System.IO;39{40    {41        static void Main(string[] args)42        {43            string path = @"C:\Users\user\Documents\Visual Studio 2015\Projects\ConsoleApplication1\ConsoleApplication1\bin\Debug\ConsoleApplication1.exe";44            Assembly assembly = Assembly.LoadFrom(path);45            var types = assembly.GetTypes();46            foreach (var type in types)47            {48                var methods = type.GetMethods(BindingFlags.NonPublic | BindingFlags.Public | BindingFlags.Static | BindingFlags.Instance);49                foreach (var method in methods)50                {51                    if (ExceptionFilterRewritingPass.IsAsyncStateMachineHandler(method))52                    {53                        Console.WriteLine("Method {0} is an async state machine handler", method.Name);54                    }55                }56            }57            Console.ReadLine();58        }59    }60}

IsAsyncStateMachineHandler

Using AI Code Generation

1using Microsoft.Coyote.Rewriting;2using System;3using System.Reflection;4using System.Threading.Tasks;5{6    {7        static void Main(string[] args)8        {9            var m = typeof(Program).GetMethod("TestAsync", BindingFlags.NonPublic | BindingFlags.Instance);10            var isAsync = ExceptionFilterRewritingPass.IsAsyncStateMachineHandler(m);11            Console.WriteLine(isAsync);12        }13        async Task TestAsync()14        {15            await Task.Yield();16        }17    }18}

IsAsyncStateMachineHandler

Using AI Code Generation

1using System;2using System.Threading.Tasks;3using Microsoft.Coyote.Rewriting;4using System.Reflection;5{6    {7        static void Main(string[] args)8        {9            var method = typeof(Program).GetMethod("TestMethod1");10            var isAsyncStateMachineHandler = ExceptionFilterRewritingPass.IsAsyncStateMachineHandler(method);11            Console.WriteLine($"Is TestMethod1 async state machine handler: {isAsyncStateMachineHandler}");12            Console.ReadLine();13        }14        static async Task TestMethod1()15        {16            await Task.Delay(1000);17        }18    }19}

IsAsyncStateMachineHandler

Using AI Code Generation

1using System;2using System.Reflection;3using System.Threading.Tasks;4using Microsoft.Coyote.Rewriting;5using System.IO;6using System.Linq;7using System.Collections.Generic;8using System.Diagnostics;9using System.Runtime.CompilerServices;10using System.Threading;11using Microsoft.Coyote.Runtime;12using Microsoft.Coyote.Specifications;13using Microsoft.Coyote.Tasks;14using Microsoft.Coyote.Tests.Common;15using Microsoft.Coyote.Tests.Common.Events;16using Microsoft.Coyote.Tests.Common.Tasks;17using Microsoft.Coyote.Tests.Common.Timers;18using Microsoft.Coyote.Tests.Common.Utilities;19using Microsoft.Coyote.Tests.Common.Coverage;20using Microsoft.Coyote.Tests.Common.Actors;21using Microsoft.Coyote.Tests.Common.Runtime;22using Microsoft.Coyote.Tests.Common.Telemetry;23using Microsoft.Coyote.Tests.Common.CoyoteSystem;24using Microsoft.Coyote.Tests.Common.SchedulingStrategies;25using Microsoft.Coyote.Tests.Common.TestingServices;26using Microsoft.Coyote.Tests.Common.TestReporters;27using Microsoft.Coyote.Tests.Common.TestScenarios;28using Microsoft.Coyote.Tests.Common.TestingServices.Coverage;29using Microsoft.Coyote.Tests.Common.TestingServices.Timers;30using Microsoft.Coyote.Tests.Common.TestingServices.Scheduling;31using Microsoft.Coyote.Tests.Common.TestingServices.RaceDetection;32using Microsoft.Coyote.Tests.Common.TestingServices.StateCaching;33using Microsoft.Coyote.Tests.Common.TestingServices.StateCaching.Strategies;34using Microsoft.Coyote.Tests.Common.TestingServices.StateCaching.Strategies.Default;35using Microsoft.Coyote.Tests.Common.TestingServices.StateCaching.Strategies.Lru;36using Microsoft.Coyote.Tests.Common.TestingServices.StateCaching.Strategies.Mru;37using Microsoft.Coyote.Tests.Common.TestingServices.StateCaching.Strategies.TwoQ;38using Microsoft.Coyote.Tests.Common.TestingServices.StateCaching.Strategies.TwoQPlus;39using Microsoft.Coyote.Tests.Common.TestingServices.StateCaching.Strategies.TwoQPlusPlus;40using Microsoft.Coyote.Tests.Common.TestingServices.StateCaching.Strategies.TwoQPlusPlusPlus;41using Microsoft.Coyote.Tests.Common.TestingServices.StateCaching.Strategies.TwoQPlusPlusPlusPlus;42using Microsoft.Coyote.Tests.Common.TestingServices.StateCaching.Strategies.TwoQPlusPlusPlusPlusPlus;

IsAsyncStateMachineHandler

Using AI Code Generation

1using System;2using System.Reflection;3using Microsoft.Coyote.Rewriting;4{5    {6        static void Main(string[] args)7        {8            var assembly = Assembly.LoadFrom(@"C:\Users\user\source\repos\3\bin\Debug9etcoreapp3.1\3.dll");10            var type = assembly.GetType("CoyoteTest.Program");11            var method = type.GetMethod("M");12            Console.WriteLine(ExceptionFilterRewritingPass.IsAsyncStateMachineHandler(method));13        }14        public static async void M()15        {16            await Task.CompletedTask;17        }18    }19}

IsAsyncStateMachineHandler

Using AI Code Generation

1using System;2using System.Collections.Generic;3using System.Linq;4using System.Text;5using System.Threading.Tasks;6using Microsoft.Coyote.Rewriting;7{8    {9        static void Main(string[] args)10        {11            Console.WriteLine("Hello World");12            {13                throw new Exception();14            }15            catch (Exception e) when (ExceptionFilterRewritingPass.IsAsyncStateMachineHandler(e))16            {17                Console.WriteLine("Exception is handled by an async state machine");18            }19        }20    }21}22using Microsoft.Coyote.Tests.Common.Coverage;23using Microsoft.Coyote.Tests.Common.Actors;24using Microsoft.Coyote.Tests.Common.Runtime;25using Microsoft.Coyote.Tests.Common.Telemetry;26using Microsoft.Coyote.Tests.Common.CoyoteSystem;27using Microsoft.Coyote.Tests.Common.SchedulingStrategies;28using Microsoft.Coyote.Tests.Common.TestingServices;29using Microsoft.Coyote.Tests.Common.TestReporters;30using Microsoft.Coyote.Tests.Common.TestScenarios;31using Microsoft.Coyote.Tests.Common.TestingServices.Coverage;32using Microsoft.Coyote.Tests.Common.TestingServices.Timers;33using Microsoft.Coyote.Tests.Common.TestingServices.Scheduling;34using Microsoft.Coyote.Tests.Common.TestingServices.RaceDetection;35using Microsoft.Coyote.Tests.Common.TestingServices.StateCaching;36using Microsoft.Coyote.Tests.Common.TestingServices.StateCaching.Strategies;37using Microsoft.Coyote.Tests.Common.TestingServices.StateCaching.Strategies.Default;38using Microsoft.Coyote.Tests.Common.TestingServices.StateCaching.Strategies.Lru;39using Microsoft.Coyote.Tests.Common.TestingServices.StateCaching.Strategies.Mru;40using Microsoft.Coyote.Tests.Common.TestingServices.StateCaching.Strategies.TwoQ;41using Microsoft.Coyote.Tests.Common.TestingServices.StateCaching.Strategies.TwoQPlus;42using Microsoft.Coyote.Tests.Common.TestingServices.StateCaching.Strategies.TwoQPlusPlus;43using Microsoft.Coyote.Tests.Common.TestingServices.StateCaching.Strategies.TwoQPlusPlusPlus;44using Microsoft.Coyote.Tests.Common.TestingServices.StateCaching.Strategies.TwoQPlusPlusPlusPlus;45using Microsoft.Coyote.Tests.Common.TestingServices.StateCaching.Strategies.TwoQPlusPlusPlusPlusPlus;

IsAsyncStateMachineHandler

Using AI Code Generation

1using System;2using System.Reflection;3using Microsoft.Coyote.Rewriting;4{5    {6        static void Main(string[] args)7        {8            var assembly = Assembly.LoadFrom(@"C:\Users\user\source\repos\3\bin\Debug9etcoreapp3.1\3.dll");10            var type = assembly.GetType("CoyoteTest.Program");11            var method = type.GetMethod("M");12            Console.WriteLine(ExceptionFilterRewritingPass.IsAsyncStateMachineHandler(method));13        }14        public static async void M()15        {16            await Task.CompletedTask;17        }18    }19}

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