Remove most RuntimeAsyncTask<T> instance methods by jakobbotsch · Pull Request #127447 · dotnet/runtime

jakobbotsch · 2026-04-27T10:29:49Z

Introduce RuntimeAsyncTaskCore that contains most of the runtime async machinery, to avoid this machinery being instantiated for every T in a RuntimeAsyncTask<T>. To do so we need a few changes:

The delegates in RuntimeAsyncTask<T> called DispatchContinuations directly. Now there are delegates in RuntimeAsyncTaskCore that call ExecuteFromThreadPool, which is known to delegate to DispatchContinuations for RuntimeAsyncTask<T>.
DispatchContinuations needs to access Task<T>.m_result. This now gets passed as a byref to RuntimeAsyncTaskCore.DispatchContinuations.

There is a 3-4% perf regression for micro benchmarks suspending/resuming that I am working on.

NativeAOT test sizes

BaseSize	DiffSize	Delta	Percent	Name
20,030,464	19,988,480	-41,984	-0.210%	System.Net.WebSockets.Client.Tests.exe
14,931,968	14,901,248	-30,720	-0.206%	System.Xml.Linq.Streaming.Tests.exe
16,546,304	16,515,584	-30,720	-0.186%	System.Xml.Linq.Events.Tests.exe
16,701,952	16,671,232	-30,720	-0.184%	System.Xml.Linq.Properties.Tests.exe
10,068,992	10,050,560	-18,432	-0.183%	System.IO.Compression.ZipFile.Tests.exe
16,813,568	16,782,848	-30,720	-0.183%	System.Xml.Linq.Misc.Tests.exe
17,095,168	17,064,448	-30,720	-0.180%	System.Xml.Linq.xNodeBuilder.Tests.exe
17,155,072	17,124,352	-30,720	-0.179%	System.Xml.Linq.TreeManipulation.Tests.exe
22,769,664	22,729,216	-40,448	-0.178%	System.Net.Sockets.Tests.exe
17,038,336	17,008,128	-30,208	-0.177%	System.Xml.Linq.xNodeReader.Tests.exe
16,594,432	16,565,248	-29,184	-0.176%	System.Linq.AsyncEnumerable.Tests.exe
9,656,832	9,639,936	-16,896	-0.175%	Microsoft.Extensions.Hosting.Functional.Tests.exe
16,982,016	16,953,344	-28,672	-0.169%	System.Private.CoreLib.dll
19,555,328	19,523,584	-31,744	-0.162%	System.Diagnostics.Process.Tests.exe
31,201,792	31,152,640	-49,152	-0.158%	System.Net.Http.Functional.Tests.exe
12,174,848	12,155,904	-18,944	-0.156%	System.Net.NetworkInformation.Functional.Tests.exe
11,330,560	11,313,152	-17,408	-0.154%	System.Net.WebSockets.Tests.exe
11,273,216	11,256,320	-16,896	-0.150%	System.IO.Compression.Brotli.Tests.exe
18,390,528	18,363,392	-27,136	-0.148%	Microsoft.Extensions.Primitives.Tests.exe
18,501,120	18,474,496	-26,624	-0.144%	Microsoft.Extensions.Configuration.Tests.exe
10,665,984	10,650,624	-15,360	-0.144%	System.IO.Pipelines.Tests.exe
18,365,440	18,339,328	-26,112	-0.142%	Microsoft.Extensions.FileProviders.Composite.Tests.exe
18,784,256	18,758,144	-26,112	-0.139%	Microsoft.Extensions.FileProviders.Physical.Tests.exe
18,462,720	18,437,120	-25,600	-0.139%	Microsoft.Extensions.Configuration.FileExtensions.Tests.exe
19,980,800	19,953,152	-27,648	-0.138%	Microsoft.Extensions.Logging.Tests.exe
10,054,144	10,040,320	-13,824	-0.137%	System.Net.ServerSentEvents.Tests.exe
9,775,104	9,761,792	-13,312	-0.136%	System.Net.WebProxy.Tests.exe
20,997,120	20,968,960	-28,160	-0.134%	System.Net.Quic.Functional.Tests.exe
9,189,888	9,177,600	-12,288	-0.134%	System.ServiceProcess.ServiceController.Tests.exe
9,561,088	9,548,288	-12,800	-0.134%	System.Memory.Data.Tests.exe
14,579,200	14,559,744	-19,456	-0.133%	System.Net.WebClient.Tests.exe
10,103,808	10,090,496	-13,312	-0.132%	Microsoft.Extensions.Caching.Memory.Tests.exe
19,878,912	19,852,800	-26,112	-0.131%	System.Text.Encoding.Tests.exe
12,421,632	12,406,272	-15,360	-0.124%	System.Xml.Linq.SDMSample.Tests.exe
10,485,248	10,472,448	-12,800	-0.122%	System.Net.Http.WinHttpHandler.Unit.Tests.exe
19,072,512	19,049,472	-23,040	-0.121%	System.Net.HttpListener.Tests.exe
13,251,584	13,235,712	-15,872	-0.120%	System.IO.Packaging.Tests.exe
12,855,296	12,839,936	-15,360	-0.119%	System.Xml.Schema.Extensions.Tests.exe
19,614,208	19,591,168	-23,040	-0.117%	System.IO.Compression.Tests.exe
28,832,768	28,798,976	-33,792	-0.117%	System.Net.Http.WinHttpHandler.Functional.Tests.exe
10,280,448	10,268,672	-11,776	-0.115%	System.Threading.Channels.Tests.exe
21,728,256	21,703,168	-25,088	-0.115%	System.IO.FileSystem.Tests.exe
13,876,224	13,860,352	-15,872	-0.114%	Microsoft.Extensions.Configuration.Functional.Tests.exe
24,296,448	24,268,800	-27,648	-0.114%	Microsoft.Extensions.Http.Tests.exe
13,948,928	13,933,056	-15,872	-0.114%	Microsoft.Extensions.Configuration.Xml.Tests.exe
19,299,328	19,277,312	-22,016	-0.114%	System.IO.Pipes.Tests.exe
14,134,784	14,118,912	-15,872	-0.112%	System.DirectoryServices.Protocols.Tests.exe
115,773,440	115,646,464	-126,976	-0.110%	System.Text.Json.SourceGeneration.Roslyn4.4.Tests.exe
8,810,496	8,800,768	-9,728	-0.110%	System.Console.Manual.Tests.exe
8,964,608	8,954,880	-9,728	-0.109%	System.Net.Primitives.Pal.Tests.exe
18,841,600	18,821,120	-20,480	-0.109%	System.Runtime.Caching.Tests.exe
33,202,176	33,166,336	-35,840	-0.108%	System.Private.Xml.Tests.exe
8,580,608	8,571,392	-9,216	-0.107%	System.Resources.Writer.Tests.exe
8,732,160	8,722,944	-9,216	-0.106%	Invariant.Tests.exe
8,691,712	8,682,496	-9,216	-0.106%	System.Diagnostics.FileVersionInfo.Tests.exe
26,451,456	26,423,808	-27,648	-0.105%	System.ComponentModel.TypeConverter.Tests.exe
27,176,448	27,148,288	-28,160	-0.104%	Microsoft.Extensions.Hosting.Unit.Tests.exe
17,439,744	17,421,824	-17,920	-0.103%	System.Net.Ping.Functional.Tests.exe
8,977,920	8,968,704	-9,216	-0.103%	System.Runtime.Serialization.Primitives.Tests.exe
9,462,784	9,453,056	-9,728	-0.103%	Microsoft.Extensions.Configuration.Ini.Tests.exe
8,532,992	8,524,288	-8,704	-0.102%	System.Composition.AttributeModel.Tests.exe
9,058,816	9,049,600	-9,216	-0.102%	System.ValueTuple.Tests.exe
15,044,096	15,028,736	-15,360	-0.102%	System.Data.DataSetExtensions.Tests.exe
8,537,088	8,528,384	-8,704	-0.102%	System.Diagnostics.Contracts.Tests.exe
8,521,216	8,512,512	-8,704	-0.102%	System.Runtime.CompilerServices.VisualC.Tests.exe
8,566,784	8,558,080	-8,704	-0.102%	Microsoft.Bcl.Numerics.Tests.exe
8,522,240	8,513,536	-8,704	-0.102%	System.ComponentModel.Tests.exe
8,532,480	8,523,776	-8,704	-0.102%	System.Text.Encoding.Extensions.Tests.exe
17,161,728	17,144,320	-17,408	-0.101%	IcuAppLocal.Tests.exe
9,136,128	9,126,912	-9,216	-0.101%	System.ComponentModel.Primitives.Tests.exe
8,598,528	8,589,824	-8,704	-0.101%	System.Composition.Runtime.Tests.exe
8,627,712	8,619,008	-8,704	-0.101%	System.Globalization.CalendarsWithConfigSwitch.Tests.exe
15,771,648	15,755,776	-15,872	-0.101%	System.Windows.Extensions.Tests.exe
8,598,016	8,589,312	-8,704	-0.101%	System.Xml.Linq.Axes.Tests.exe
17,289,216	17,271,808	-17,408	-0.101%	System.Threading.Overlapped.Tests.exe
8,576,000	8,567,296	-8,704	-0.101%	Microsoft.Extensions.Hosting.Abstractions.Tests.exe
17,800,704	17,782,784	-17,920	-0.101%	System.Formats.Tar.Manual.Tests.exe
17,668,608	17,650,688	-17,920	-0.101%	System.IO.FileSystem.Watcher.Tests.exe
8,674,816	8,666,112	-8,704	-0.100%	System.Security.Cryptography.ProtectedData.Tests.exe
8,674,816	8,666,112	-8,704	-0.100%	System.IO.FileSystem.Manual.Tests.exe
8,743,936	8,735,232	-8,704	-0.100%	System.IO.FileSystem.DriveInfo.Tests.exe
8,752,640	8,743,936	-8,704	-0.099%	Microsoft.Bcl.TimeProvider.Tests.exe
17,582,592	17,565,184	-17,408	-0.099%	MetricOuterLoop1.Tests.exe
27,917,312	27,889,664	-27,648	-0.099%	System.Net.Security.Tests.exe
17,319,424	17,302,528	-16,896	-0.098%	System.Security.Principal.Windows.Tests.exe
15,086,080	15,071,232	-14,848	-0.098%	System.Security.Cryptography.Cng.Tests.exe
15,108,608	15,093,760	-14,848	-0.098%	System.Drawing.Primitives.Tests.exe
17,238,016	17,221,120	-16,896	-0.098%	System.ComponentModel.EventBasedAsync.Tests.exe
8,838,144	8,829,440	-8,704	-0.098%	System.Reflection.Extensions.Tests.exe
17,305,600	17,288,704	-16,896	-0.098%	System.Security.Claims.Tests.exe
17,222,144	17,205,248	-16,896	-0.098%	System.Net.ServicePoint.Tests.exe
11,994,624	11,982,848	-11,776	-0.098%	System.IO.Tests.exe
8,999,936	8,991,232	-8,704	-0.097%	System.Reflection.TypeExtensions.Tests.exe
9,013,760	9,005,056	-8,704	-0.097%	Microsoft.Extensions.FileSystemGlobbing.Tests.exe
17,438,208	17,421,312	-16,896	-0.097%	System.Diagnostics.TraceSource.Tests.exe
17,337,344	17,320,448	-16,896	-0.097%	System.Threading.Timer.Tests.exe
17,974,784	17,957,376	-17,408	-0.097%	System.Threading.ThreadPool.WindowsThreadPool.Tests.exe
17,974,784	17,957,376	-17,408	-0.097%	System.Threading.ThreadPool.Tests.exe
17,362,944	17,346,048	-16,896	-0.097%	Microsoft.Win32.SystemEvents.Tests.exe
8,927,232	8,918,528	-8,704	-0.097%	Microsoft.Bcl.Memory.Tests.exe
8,965,632	8,956,928	-8,704	-0.097%	Microsoft.Win32.Registry.Tests.exe
18,459,648	18,441,728	-17,920	-0.097%	System.Threading.Tasks.Parallel.Tests.exe
17,664,512	17,647,616	-16,896	-0.096%	System.Buffers.Tests.exe
9,083,392	9,074,688	-8,704	-0.096%	System.IO.FileSystem.AccessControl.Tests.exe
19,688,448	19,669,504	-18,944	-0.096%	System.Net.Http.Unit.Tests.exe
17,623,552	17,606,656	-16,896	-0.096%	System.Threading.Thread.Tests.exe
18,136,064	18,118,656	-17,408	-0.096%	System.Diagnostics.TextWriterTraceListener.Tests.exe
8,522,752	8,514,560	-8,192	-0.096%	System.Diagnostics.Tools.Tests.exe
18,184,704	18,167,296	-17,408	-0.096%	System.Text.Encoding.CodePages.Tests.exe
18,071,040	18,053,632	-17,408	-0.096%	System.Console.Tests.exe
17,167,360	17,150,976	-16,384	-0.095%	System.Runtime.Serialization.Formatters.Disabled.Tests.exe
8,644,096	8,635,904	-8,192	-0.095%	System.Runtime.Handles.Tests.exe
21,104,640	21,084,672	-19,968	-0.095%	System.Net.Requests.Tests.exe
17,295,872	17,279,488	-16,384	-0.095%	System.Runtime.InteropServices.RuntimeInformation.Tests.exe
17,243,136	17,226,752	-16,384	-0.095%	System.Runtime.InvariantTimezone.Tests.exe
8,615,424	8,607,232	-8,192	-0.095%	System.Net.WebHeaderCollection.Tests.exe
8,654,848	8,646,656	-8,192	-0.095%	System.Runtime.CompilerServices.Unsafe.Tests.exe
8,662,016	8,653,824	-8,192	-0.095%	System.Runtime.InteropServices.ComDisabled.Tests.exe
9,732,096	9,722,880	-9,216	-0.095%	System.Threading.RateLimiting.Tests.exe
17,744,896	17,728,000	-16,896	-0.095%	System.Threading.Tasks.Extensions.Tests.exe
9,139,712	9,131,008	-8,704	-0.095%	System.Globalization.Calendars.Tests.exe
9,181,184	9,172,480	-8,704	-0.095%	Microsoft.Extensions.Configuration.EnvironmentVariables.Tests.exe
16,113,152	16,097,792	-15,360	-0.095%	System.Data.Odbc.Tests.exe
18,039,296	18,022,400	-16,896	-0.094%	Microsoft.Extensions.Diagnostics.Tests.exe
8,693,760	8,685,568	-8,192	-0.094%	System.Private.Uri.Unit.Tests.exe
17,368,576	17,352,192	-16,384	-0.094%	System.Diagnostics.StackTrace.Tests.exe
17,577,472	17,561,088	-16,384	-0.093%	MetricOuterLoop.Tests.exe
8,785,408	8,777,216	-8,192	-0.093%	System.Resources.Reader.Tests.exe
9,331,712	9,323,008	-8,704	-0.093%	Microsoft.Extensions.Diagnostics.Abstractions.Tests.exe
9,923,072	9,913,856	-9,216	-0.093%	System.Collections.NonGeneric.Tests.exe
9,351,168	9,342,464	-8,704	-0.093%	System.Net.Mail.Unit.Tests.exe
9,335,296	9,326,592	-8,704	-0.093%	System.Security.Permissions.Tests.exe
8,791,552	8,783,360	-8,192	-0.093%	System.Web.HttpUtility.Tests.exe
9,339,904	9,331,200	-8,704	-0.093%	System.Reflection.Context.Tests.exe
10,037,760	10,028,544	-9,216	-0.092%	System.Diagnostics.Debug.Tests.exe
8,903,680	8,895,488	-8,192	-0.092%	System.IO.Pipes.AccessControl.Tests.exe
29,413,888	29,386,752	-27,136	-0.092%	Microsoft.Extensions.DependencyModel.Tests.exe
18,525,184	18,508,288	-16,896	-0.091%	System.IO.MemoryMappedFiles.Tests.exe
19,087,360	19,069,952	-17,408	-0.091%	Microsoft.Extensions.Hosting.WindowsServices.Tests.exe
9,605,120	9,596,416	-8,704	-0.091%	System.Composition.Convention.Tests.exe
9,030,656	9,022,464	-8,192	-0.091%	Microsoft.Extensions.Configuration.CommandLine.Tests.exe
18,496,000	18,479,104	-16,896	-0.091%	Microsoft.Extensions.Hosting.Systemd.Tests.exe
19,302,912	19,285,504	-17,408	-0.090%	System.Net.Primitives.Functional.Tests.exe
18,700,800	18,683,904	-16,896	-0.090%	Microsoft.Extensions.Logging.Console.Tests.exe
8,517,632	8,509,952	-7,680	-0.090%	System.IO.FileSystem.Primitives.Tests.exe
9,621,504	9,612,800	-8,704	-0.090%	System.Private.Uri.Functional.Tests.exe
9,117,184	9,108,992	-8,192	-0.090%	System.Security.AccessControl.Tests.exe
9,678,848	9,670,144	-8,704	-0.090%	System.Text.RegularExpressions.Unit.Tests.exe
9,723,392	9,714,688	-8,704	-0.090%	System.Collections.Specialized.Tests.exe
8,621,056	8,613,376	-7,680	-0.089%	Microsoft.Win32.Registry.AccessControl.Tests.exe
8,637,952	8,630,272	-7,680	-0.089%	Microsoft.Win32.Primitives.Tests.exe
20,810,240	20,791,808	-18,432	-0.089%	System.Security.Cryptography.Csp.Tests.exe
9,737,728	9,729,024	-8,704	-0.089%	System.Formats.Asn1.Tests.exe
18,378,752	18,362,368	-16,384	-0.089%	System.Threading.Tests.exe
9,826,304	9,817,600	-8,704	-0.089%	System.Formats.Nrbf.Tests.exe
8,677,888	8,670,208	-7,680	-0.089%	System.Security.SecureString.Tests.exe
19,756,032	19,738,624	-17,408	-0.088%	System.Resources.ResourceManager.Tests.exe
9,936,896	9,928,192	-8,704	-0.088%	LibraryImportGenerator.Tests.exe
20,292,608	20,274,688	-17,920	-0.088%	System.Threading.Tasks.Dataflow.Tests.exe
18,593,280	18,576,896	-16,384	-0.088%	ComInterfaceGenerator.Tests.exe
9,289,216	9,281,024	-8,192	-0.088%	System.Net.Primitives.UnitTests.Tests.exe
19,491,328	19,474,432	-16,896	-0.087%	Microsoft.Extensions.Configuration.UserSecrets.Tests.exe
9,439,232	9,431,040	-8,192	-0.087%	Microsoft.Extensions.Logging.Testing.Tests.exe
20,082,688	20,065,280	-17,408	-0.087%	System.Formats.Tar.Tests.exe
20,241,408	20,224,000	-17,408	-0.086%	System.Runtime.InteropServices.Tests.exe
8,933,376	8,925,696	-7,680	-0.086%	System.Threading.AccessControl.Tests.exe
19,561,984	19,545,088	-16,896	-0.086%	Microsoft.Extensions.Configuration.Json.Tests.exe
9,512,960	9,504,768	-8,192	-0.086%	System.IO.Hashing.Tests.exe
20,539,392	20,521,984	-17,408	-0.085%	System.Runtime.Extensions.Tests.exe
20,461,056	20,443,648	-17,408	-0.085%	System.Reflection.Tests.exe
9,015,296	9,007,616	-7,680	-0.085%	System.Net.NameResolution.Pal.Tests.exe
20,484,096	20,466,688	-17,408	-0.085%	System.Diagnostics.DiagnosticSource.Tests.exe
20,551,680	20,534,272	-17,408	-0.085%	System.Threading.Tasks.Tests.exe
21,079,552	21,061,632	-17,920	-0.085%	Microsoft.Extensions.Logging.EventSource.Tests.exe
11,023,872	11,014,656	-9,216	-0.084%	System.Runtime.Numerics.Tests.exe
21,629,440	21,611,520	-17,920	-0.083%	System.Data.OleDb.Tests.exe
10,507,776	10,499,072	-8,704	-0.083%	Microsoft.Extensions.Options.Tests.exe
9,249,280	9,241,600	-7,680	-0.083%	Microsoft.Bcl.AsyncInterfaces.Tests.exe
9,325,056	9,317,376	-7,680	-0.082%	System.IO.IsolatedStorage.Tests.exe
11,585,024	11,575,808	-9,216	-0.080%	System.Net.Http.Json.Unit.Tests.exe
9,600,512	9,592,832	-7,680	-0.080%	System.Diagnostics.EventLog.Tests.exe
12,254,208	12,244,480	-9,728	-0.079%	System.Reflection.Metadata.Tests.exe
20,747,776	20,731,392	-16,384	-0.079%	System.Collections.Concurrent.Tests.exe
10,574,336	10,566,144	-8,192	-0.077%	Common.Tests.exe
11,457,536	11,448,832	-8,704	-0.076%	System.IO.Ports.Tests.exe
10,934,272	10,926,080	-8,192	-0.075%	System.Runtime.Intrinsics.Tests.exe
9,649,664	9,642,496	-7,168	-0.074%	System.IO.UnmanagedMemoryStream.Tests.exe
11,767,808	11,759,104	-8,704	-0.074%	System.Security.Cryptography.Cose.Tests.exe
23,411,712	23,394,816	-16,896	-0.072%	System.Memory.Tests.exe
11,351,040	11,342,848	-8,192	-0.072%	System.Net.Security.Unit.Tests.exe
25,900,544	25,882,112	-18,432	-0.071%	System.Text.Json.SourceGeneration.Roslyn3.11.Tests.exe
11,167,232	11,159,552	-7,680	-0.069%	System.Text.Encodings.Web.Tests.exe
26,013,184	25,995,776	-17,408	-0.067%	System.Globalization.Nls.Tests.exe
11,582,976	11,575,296	-7,680	-0.066%	System.Resources.Extensions.Tests.exe
26,102,272	26,085,376	-16,896	-0.065%	System.Globalization.Tests.exe
44,718,080	44,688,896	-29,184	-0.065%	System.Runtime.Tests.exe
15,199,744	15,190,528	-9,216	-0.061%	System.Linq.Tests.exe
15,374,336	15,365,632	-8,704	-0.057%	System.Globalization.Extensions.Tests.exe
15,374,336	15,365,632	-8,704	-0.057%	System.Globalization.Extensions.Nls.Tests.exe
32,745,472	32,728,064	-17,408	-0.053%	System.Linq.Expressions.Tests.exe
33,392,640	33,375,232	-17,408	-0.052%	Microsoft.Bcl.Cryptography.Tests.exe
17,812,480	17,803,776	-8,704	-0.049%	System.Collections.Tests.exe
18,752,000	18,742,784	-9,216	-0.049%	System.Numerics.Vectors.Tests.exe
22,308,864	22,299,648	-9,216	-0.041%	System.Security.Cryptography.Pkcs.Tests.exe
45,498,368	45,479,936	-18,432	-0.041%	System.Security.Cryptography.Tests.exe

Introduce `RuntimeAsyncTaskCore` that contains most of the runtime async machinery, to avoid this machinery being instantiated for every `T` in a `RuntimeAsyncTask<T>`. To do so we need a few changes: - The delegates in `RuntimeAsyncTask<T>` called `DispatchContinuations` directly. Now there are delegates in `RuntimeAsyncTaskCore` that call `ExecuteFromThreadPool`, which is known to delegate to `DispatchContinuations` for `RuntimeAsyncTask<T>`. - `DispatchContinuations` needs to access `Task<T>.m_result`. This now gets passed as a byref to `RuntimeAsyncTaskCore.DispatchContinuations`.

Copilot

Pull request overview

This PR refactors the CoreCLR runtime-async “suspend/resume” machinery by moving most per-T logic out of RuntimeAsyncTask<T> into a new non-generic RuntimeAsyncTaskCore, aiming to reduce generic instantiations and associated code size/overhead.

Changes:

Introduces RuntimeAsyncTaskCore static helpers and routes RuntimeAsyncTask<T> dispatch/suspension logic through it, passing Task<T>.m_result storage byref.
Updates completion flow to use Task.TrySetResult() (implied result is the current m_result value) instead of TrySetResult(m_result).
Adjusts a stack reflection test to match the new dispatcher signature.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 4 comments.

File	Description
`src/coreclr/System.Private.CoreLib/src/System/Runtime/CompilerServices/AsyncHelpers.CoreCLR.cs`	Extracts runtime-async dispatch/suspension logic into `RuntimeAsyncTaskCore` and updates dispatch paths/callbacks accordingly.
`src/libraries/System.Private.CoreLib/src/System/Threading/Tasks/Task.cs`	Broadens `m_stateObject` visibility and updates `TrySetResult()` remark to align with implied-result behavior.
`src/tests/async/reflection/reflection.cs`	Updates expected stack frame method signature for the dispatcher after refactor.

Copilot · 2026-04-27T10:34:45Z

+                Debug.Assert(state is Task && state.GetType().GetGenericTypeDefinition() == typeof(RuntimeAsyncTask<>));
+                Task runtimeAsyncTask = Unsafe.As<Task>(state);
+                // Relies on us knowing that RuntimeAsyncTask.ExecuteFromThreadPool is a simple forward to DispatchContinuations
+                runtimeAsyncTask.ExecuteFromThreadPool(null!);
            };


In this path state is passed through SynchronizationContext.Post, which can be overridden by user code and may invoke the callback with an unexpected (or null) state. Using Unsafe.As<Task>(state) can turn that into a type-safety hole; prefer a normal cast/pattern match (and fail fast if it's not the expected RuntimeAsyncTask<>), and avoid relying on ExecuteFromThreadPool(null!) as a dispatch mechanism.

Hmm, fair point.

dotnet-policy-service · 2026-04-27T10:52:34Z

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Copilot AI review requested due to automatic review settings April 27, 2026 10:29

dotnet-policy-service Bot assigned jakobbotsch Apr 27, 2026

github-actions Bot added the area-System.Reflection label Apr 27, 2026

Copilot started reviewing on behalf of jakobbotsch April 27, 2026 10:30 View session

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jakobbotsch added area-VM-coreclr runtime-async and removed area-System.Reflection labels Apr 27, 2026

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Remove most RuntimeAsyncTask<T> instance methods#127447

Remove most RuntimeAsyncTask<T> instance methods#127447
jakobbotsch wants to merge 1 commit intodotnet:mainfrom
jakobbotsch:one-HandleSuspended

jakobbotsch commented Apr 27, 2026 •

edited

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jakobbotsch commented Apr 27, 2026 •

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