Changed ManualResetValueTaskSource to AutoResetValueTaskSource.

Author: timcassell

…et/Helpers/ManualResetValueTaskSource.cs …tNet/Helpers/AutoResetValueTaskSource.cssrc/BenchmarkDotNet/Helpers/ManualResetValueTaskSource.cs renamed to src/BenchmarkDotNet/Helpers/AutoResetValueTaskSource.cs src/BenchmarkDotNet/Helpers/ManualResetValueTaskSource.cs renamed to src/BenchmarkDotNet/Helpers/AutoResetValueTaskSource.cs

@@ -1,40 +1,26 @@
-// Licensed to the .NET Foundation under one or more agreements.
-// The .NET Foundation licenses this file to you under the MIT license.
-
-using JetBrains.Annotations;
+using JetBrains.Annotations;
 using System;
 using System.Diagnostics;
 using System.Runtime.ExceptionServices;
-using System.Runtime.InteropServices;
 using System.Threading;
+using System.Threading.Tasks;
 using System.Threading.Tasks.Sources;
 
 namespace BenchmarkDotNet.Helpers
 {
-    /// <summary>Provides the core logic for implementing a manual-reset <see cref="IValueTaskSource"/> or <see cref="IValueTaskSource{TResult}"/>.</summary>
-    /// <typeparam name="TResult"></typeparam>
-    [StructLayout(LayoutKind.Auto)]
-    public class ManualResetValueTaskSource<TResult> : IValueTaskSource<TResult>, IValueTaskSource
+    /// <summary>
+    /// Implementation for <see cref="IValueTaskSource{TResult}"/> that will reset itself when awaited so that it can be re-used.
+    /// </summary>
+    public class AutoResetValueTaskSource<TResult> : IValueTaskSource<TResult>, IValueTaskSource
     {
-        /// <summary>
-        /// The callback to invoke when the operation completes if <see cref="OnCompleted"/> was called before the operation completed,
-        /// or <see cref="ManualResetValueTaskSourceCoreShared.s_sentinel"/> if the operation completed before a callback was supplied,
-        /// or null if a callback hasn't yet been provided and the operation hasn't yet completed.
-        /// </summary>
         [CanBeNull] private Action<object> _continuation;
-        /// <summary>State to pass to <see cref="_continuation"/>.</summary>
         [CanBeNull] private object _continuationState;
-        /// <summary>Whether the current operation has completed.</summary>
         private bool _completed;
-        /// <summary>The result with which the operation succeeded, or the default value if it hasn't yet completed or failed.</summary>
         [CanBeNull] private TResult _result;
-        /// <summary>The exception with which the operation failed, or null if it hasn't yet completed or completed successfully.</summary>
         [CanBeNull] private ExceptionDispatchInfo _error;
-        /// <summary>The current version of this value, used to help prevent misuse.</summary>
         private short _version;
 
-        /// <summary>Resets to prepare for the next operation.</summary>
-        public void Reset()
+        private void Reset()
         {
             // Reset/update state for the next use/await of this instance.
             _version++;
@@ -86,8 +72,11 @@ public TResult GetResult(short token)
                 throw new InvalidOperationException();
             }
 
-            _error?.Throw();
-            return _result;
+            var result = _result;
+            var error = _error;
+            Reset();
+            error?.Throw();
+            return result;
         }
 
         public void OnCompleted(Action<object> continuation, object state, short token, ValueTaskSourceOnCompletedFlags flags)
@@ -116,7 +105,7 @@ public void OnCompleted(Action<object> continuation, object state, short token,
             if (oldContinuation != null)
             {
                 // Operation already completed, so we need to call the supplied callback.
-                if (!ReferenceEquals(oldContinuation, ManualResetValueTaskSourceCoreShared.s_sentinel))
+                if (!ReferenceEquals(oldContinuation, AutoResetValueTaskSourceCoreShared.s_sentinel))
                 {
                     throw new InvalidOperationException();
                 }
@@ -125,8 +114,6 @@ public void OnCompleted(Action<object> continuation, object state, short token,
             }
         }
 
-        /// <summary>Ensures that the specified token matches the current version.</summary>
-        /// <param name="token">The token supplied by <see cref="ValueTask"/>.</param>
         private void ValidateToken(short token)
         {
             if (token != _version)
@@ -135,7 +122,6 @@ private void ValidateToken(short token)
             }
         }
 
-        /// <summary>Signals that the operation has completed.  Invoked after the result or error has been set.</summary>
         private void SignalCompletion()
         {
             if (_completed)
@@ -144,21 +130,8 @@ private void SignalCompletion()
             }
             _completed = true;
 
-            if (_continuation != null || Interlocked.CompareExchange(ref _continuation, ManualResetValueTaskSourceCoreShared.s_sentinel, null) != null)
-            {
-                InvokeContinuation();
-            }
-        }
-
-        /// <summary>
-        /// Invokes the continuation with the appropriate captured context / scheduler.
-        /// This assumes that if <see cref="_executionContext"/> is not null we're already
-        /// running within that <see cref="ExecutionContext"/>.
-        /// </summary>
-        private void InvokeContinuation()
-        {
-            Debug.Assert(_continuation != null);
-            _continuation(_continuationState);
+            Interlocked.CompareExchange(ref _continuation, AutoResetValueTaskSourceCoreShared.s_sentinel, null)
+                ?.Invoke(_continuationState);
         }
 
         void IValueTaskSource.GetResult(short token)
@@ -167,7 +140,7 @@ void IValueTaskSource.GetResult(short token)
         }
     }
 
-    internal static class ManualResetValueTaskSourceCoreShared // separated out of generic to avoid unnecessary duplication
+    internal static class AutoResetValueTaskSourceCoreShared // separated out of generic to avoid unnecessary duplication
     {
         internal static readonly Action<object> s_sentinel = CompletionSentinel;
         private static void CompletionSentinel(object _) // named method to aid debugging

src/BenchmarkDotNet/Templates/BenchmarkType.txt

@@ -114,7 +114,7 @@
 
 #if RETURNS_AWAITABLE_$ID$
 
-        private readonly BenchmarkDotNet.Helpers.ManualResetValueTaskSource<Perfolizer.Horology.ClockSpan> valueTaskSource = new BenchmarkDotNet.Helpers.ManualResetValueTaskSource<Perfolizer.Horology.ClockSpan>();
+        private readonly BenchmarkDotNet.Helpers.AutoResetValueTaskSource<Perfolizer.Horology.ClockSpan> valueTaskSource = new BenchmarkDotNet.Helpers.AutoResetValueTaskSource<Perfolizer.Horology.ClockSpan>();
         private System.Int64 repeatsRemaining;
         private readonly System.Action continuation;
         private Perfolizer.Horology.StartedClock startedClock;
@@ -183,7 +183,6 @@
         private System.Threading.Tasks.ValueTask<Perfolizer.Horology.ClockSpan> WorkloadActionImpl(System.Int64 invokeCount, Perfolizer.Horology.IClock clock)
         {
             repeatsRemaining = invokeCount;
-            valueTaskSource.Reset();
             startedClock = Perfolizer.Horology.ClockExtensions.Start(clock);
             __RunTask();
             return new System.Threading.Tasks.ValueTask<Perfolizer.Horology.ClockSpan>(valueTaskSource, valueTaskSource.Version);

src/BenchmarkDotNet/Toolchains/InProcess.Emit.Implementation/Emitters/TaskConsumeEmitter.cs

@@ -19,7 +19,7 @@ internal class TaskConsumeEmitter : ConsumeEmitter
 
         private LocalBuilder disassemblyDiagnoserLocal;
         /*
-            private readonly BenchmarkDotNet.Helpers.ManualResetValueTaskSource<Perfolizer.Horology.ClockSpan> valueTaskSource = new BenchmarkDotNet.Helpers.ManualResetValueTaskSource<Perfolizer.Horology.ClockSpan>();
+            private readonly BenchmarkDotNet.Helpers.AutoResetValueTaskSource<Perfolizer.Horology.ClockSpan> valueTaskSource = new BenchmarkDotNet.Helpers.AutoResetValueTaskSource<Perfolizer.Horology.ClockSpan>();
             private System.Int64 repeatsRemaining;
             private readonly System.Action continuation;
             private Perfolizer.Horology.StartedClock startedClock;
@@ -48,7 +48,7 @@ protected override void OnDefineFieldsOverride(TypeBuilder runnableBuilder)
                     && !m.GetParameterTypes().First().IsByRef)
                 .MakeGenericMethod(ConsumableInfo.OverheadMethodReturnType);
 
-            valueTaskSourceField = runnableBuilder.DefineField(ValueTaskSourceFieldName, typeof(Helpers.ManualResetValueTaskSource<ClockSpan>), FieldAttributes.Private | FieldAttributes.InitOnly);
+            valueTaskSourceField = runnableBuilder.DefineField(ValueTaskSourceFieldName, typeof(Helpers.AutoResetValueTaskSource<ClockSpan>), FieldAttributes.Private | FieldAttributes.InitOnly);
             repeatsRemainingField = runnableBuilder.DefineField(RepeatsRemainingFieldName, typeof(long), FieldAttributes.Private);
             continuationField = runnableBuilder.DefineField(ContinuationFieldName, typeof(Action), FieldAttributes.Private | FieldAttributes.InitOnly);
             startedClockField = runnableBuilder.DefineField(StartedClockFieldName, typeof(StartedClock), FieldAttributes.Private);
@@ -72,15 +72,15 @@ protected override void EmitDisassemblyDiagnoserReturnDefaultOverride(ILGenerato
 
         protected override void OnEmitCtorBodyOverride(ConstructorBuilder constructorBuilder, ILGenerator ilBuilder)
         {
-            var ctor = typeof(Helpers.ManualResetValueTaskSource<ClockSpan>).GetConstructor(Array.Empty<Type>());
+            var ctor = typeof(Helpers.AutoResetValueTaskSource<ClockSpan>).GetConstructor(Array.Empty<Type>());
             if (ctor == null)
-                throw new InvalidOperationException($"Cannot get default .ctor for {typeof(Helpers.ManualResetValueTaskSource<ClockSpan>)}");
+                throw new InvalidOperationException($"Cannot get default .ctor for {typeof(Helpers.AutoResetValueTaskSource<ClockSpan>)}");
 
             /*
-                // valueTaskSourceField = new BenchmarkDotNet.Helpers.ManualResetValueTaskSource<Perfolizer.Horology.ClockSpan>();
+                // valueTaskSourceField = new BenchmarkDotNet.Helpers.AutoResetValueTaskSource<Perfolizer.Horology.ClockSpan>();
                 IL_0000: ldarg.0
-                IL_0001: newobj instance void class BenchmarkDotNet.Helpers.ManualResetValueTaskSource`1<valuetype Perfolizer.Horology.ClockSpan>::.ctor()
-                IL_0006: stfld class BenchmarkDotNet.Helpers.ManualResetValueTaskSource`1<valuetype Perfolizer.Horology.ClockSpan> BenchmarkRunner_0::valueTaskSource
+                IL_0001: newobj instance void class BenchmarkDotNet.Helpers.AutoResetValueTaskSource`1<valuetype Perfolizer.Horology.ClockSpan>::.ctor()
+                IL_0006: stfld class BenchmarkDotNet.Helpers.AutoResetValueTaskSource`1<valuetype Perfolizer.Horology.ClockSpan> BenchmarkRunner_0::valueTaskSource
              */
             ilBuilder.Emit(OpCodes.Ldarg_0);
             ilBuilder.Emit(OpCodes.Newobj, ctor);
@@ -293,16 +293,6 @@ class Perfolizer.Horology.IClock clock
             ilBuilder.Emit(OpCodes.Ldarg_0);
             ilBuilder.EmitLdarg(toArg);
             ilBuilder.Emit(OpCodes.Stfld, repeatsRemainingField);
-            /*
-                // valueTaskSource.Reset();
-                IL_0007: ldarg.0
-                IL_0008: ldfld class BenchmarkDotNet.Helpers.ManualResetValueTaskSource`1<valuetype Perfolizer.Horology.ClockSpan> BenchmarkRunner_0::valueTaskSource
-                IL_000d: callvirt instance void class BenchmarkDotNet.Helpers.ManualResetValueTaskSource`1<valuetype Perfolizer.Horology.ClockSpan>::Reset()
-            */
-            ilBuilder.Emit(OpCodes.Ldarg_0);
-            ilBuilder.Emit(OpCodes.Ldfld, valueTaskSourceField);
-            var resetMethod = valueTaskSourceField.FieldType.GetMethod(nameof(Helpers.ManualResetValueTaskSource<ClockSpan>.Reset), BindingFlagsPublicInstance);
-            ilBuilder.Emit(OpCodes.Callvirt, resetMethod);
             /*
                 // startedClock = Perfolizer.Horology.ClockExtensions.Start(clock);
                 IL_0012: ldarg.0
@@ -324,18 +314,18 @@ class Perfolizer.Horology.IClock clock
             /*
                 // return new System.Threading.Tasks.ValueTask<Perfolizer.Horology.ClockSpan>(valueTaskSource, valueTaskSource.Version);
                 IL_0024: ldarg.0
-                IL_0025: ldfld class BenchmarkDotNet.Helpers.ManualResetValueTaskSource`1<valuetype Perfolizer.Horology.ClockSpan> BenchmarkRunner_0::valueTaskSource
+                IL_0025: ldfld class BenchmarkDotNet.Helpers.AutoResetValueTaskSource`1<valuetype Perfolizer.Horology.ClockSpan> BenchmarkRunner_0::valueTaskSource
                 IL_002a: ldarg.0
-                IL_002b: ldfld class BenchmarkDotNet.Helpers.ManualResetValueTaskSource`1<valuetype Perfolizer.Horology.ClockSpan> BenchmarkRunner_0::valueTaskSource
-                IL_0030: callvirt instance int16 class BenchmarkDotNet.Helpers.ManualResetValueTaskSource`1<valuetype Perfolizer.Horology.ClockSpan>::get_Version()
+                IL_002b: ldfld class BenchmarkDotNet.Helpers.AutoResetValueTaskSource`1<valuetype Perfolizer.Horology.ClockSpan> BenchmarkRunner_0::valueTaskSource
+                IL_0030: callvirt instance int16 class BenchmarkDotNet.Helpers.AutoResetValueTaskSource`1<valuetype Perfolizer.Horology.ClockSpan>::get_Version()
                 IL_0035: newobj instance void valuetype [System.Private.CoreLib]System.Threading.Tasks.ValueTask`1<valuetype Perfolizer.Horology.ClockSpan>::.ctor(class [System.Private.CoreLib]System.Threading.Tasks.Sources.IValueTaskSource`1<!0>, int16)
                 IL_003a: ret
             */
             ilBuilder.Emit(OpCodes.Ldarg_0);
             ilBuilder.Emit(OpCodes.Ldfld, valueTaskSourceField);
             ilBuilder.Emit(OpCodes.Ldarg_0);
             ilBuilder.Emit(OpCodes.Ldfld, valueTaskSourceField);
-            var getVersionMethod = valueTaskSourceField.FieldType.GetProperty(nameof(Helpers.ManualResetValueTaskSource<ClockSpan>.Version), BindingFlagsPublicInstance).GetGetMethod(true);
+            var getVersionMethod = valueTaskSourceField.FieldType.GetProperty(nameof(Helpers.AutoResetValueTaskSource<ClockSpan>.Version), BindingFlagsPublicInstance).GetGetMethod(true);
             ilBuilder.Emit(OpCodes.Callvirt, getVersionMethod);
             var ctor = actionMethodBuilder.ReturnType.GetConstructor(new[] { valueTaskSourceField.FieldType, getVersionMethod.ReturnType });
             ilBuilder.Emit(OpCodes.Newobj, ctor);
@@ -504,14 +494,14 @@ instance void __RunTask () cil managed
             /*
                 // valueTaskSource.SetResult(clockspan);
                 IL_008d: ldarg.0
-                IL_008e: ldfld class BenchmarkDotNet.Helpers.ManualResetValueTaskSource`1<valuetype Perfolizer.Horology.ClockSpan> BenchmarkRunner_0::valueTaskSource
+                IL_008e: ldfld class BenchmarkDotNet.Helpers.AutoResetValueTaskSource`1<valuetype Perfolizer.Horology.ClockSpan> BenchmarkRunner_0::valueTaskSource
                 IL_0093: ldloc.0
-                IL_0094: callvirt instance void class BenchmarkDotNet.Helpers.ManualResetValueTaskSource`1<valuetype Perfolizer.Horology.ClockSpan>::SetResult(!0)
+                IL_0094: callvirt instance void class BenchmarkDotNet.Helpers.AutoResetValueTaskSource`1<valuetype Perfolizer.Horology.ClockSpan>::SetResult(!0)
             */
             ilBuilder.Emit(OpCodes.Ldarg_0);
             ilBuilder.Emit(OpCodes.Ldfld, valueTaskSourceField);
             ilBuilder.EmitLdloc(clockspanLocal);
-            ilBuilder.Emit(OpCodes.Callvirt, valueTaskSourceField.FieldType.GetMethod(nameof(Helpers.ManualResetValueTaskSource<ClockSpan>.SetResult), BindingFlagsPublicInstance));
+            ilBuilder.Emit(OpCodes.Callvirt, valueTaskSourceField.FieldType.GetMethod(nameof(Helpers.AutoResetValueTaskSource<ClockSpan>.SetResult), BindingFlagsPublicInstance));
 
             ilBuilder.MarkLabel(returnLabel);
             ilBuilder.Emit(OpCodes.Ret);
@@ -627,15 +617,15 @@ class [System.Private.CoreLib]System.Exception e
             /*
                 // valueTaskSource.SetException(e);
                 IL_0018: ldarg.0
-                IL_0019: ldfld class BenchmarkDotNet.Helpers.ManualResetValueTaskSource`1<valuetype Perfolizer.Horology.ClockSpan> BenchmarkRunner_0::valueTaskSource
+                IL_0019: ldfld class BenchmarkDotNet.Helpers.AutoResetValueTaskSource`1<valuetype Perfolizer.Horology.ClockSpan> BenchmarkRunner_0::valueTaskSource
                 IL_001e: ldarg.1
-                IL_001f: callvirt instance void class BenchmarkDotNet.Helpers.ManualResetValueTaskSource`1<valuetype Perfolizer.Horology.ClockSpan>::SetException(class [System.Private.CoreLib]System.Exception)
+                IL_001f: callvirt instance void class BenchmarkDotNet.Helpers.AutoResetValueTaskSource`1<valuetype Perfolizer.Horology.ClockSpan>::SetException(class [System.Private.CoreLib]System.Exception)
                 IL_0024: ret
             */
             ilBuilder.Emit(OpCodes.Ldarg_0);
             ilBuilder.Emit(OpCodes.Ldfld, valueTaskSourceField);
             ilBuilder.EmitLdarg(exceptionArg);
-            var setExceptionMethod = valueTaskSourceField.FieldType.GetMethod(nameof(Helpers.ManualResetValueTaskSource<ClockSpan>.SetException), BindingFlagsPublicInstance);
+            var setExceptionMethod = valueTaskSourceField.FieldType.GetMethod(nameof(Helpers.AutoResetValueTaskSource<ClockSpan>.SetException), BindingFlagsPublicInstance);
             ilBuilder.Emit(OpCodes.Callvirt, setExceptionMethod);
             ilBuilder.Emit(OpCodes.Ret);