Remove boxing for awaited custom awaiters#131342
Draft
jakobbotsch wants to merge 9 commits into
Draft
Conversation
github-actions
Bot
added
the
area-CodeGen-coreclr
|
Azure Pipelines: Successfully started running 6 pipeline(s). 10 pipeline(s) were filtered out due to trigger conditions. There may be pipelines that require an authorized user to comment /azp run to run. |
Contributor
|
Tagging subscribers to this area: @JulieLeeMSFT, @jakobbotsch |
Contributor
There was a problem hiding this comment.
Pull request overview
This PR extends CoreCLR runtime-async to avoid boxing custom struct awaiters on suspension by storing the awaiter value into the continuation object and later invoking OnCompleted/UnsafeOnCompleted by extracting the awaiter from that continuation using a JIT-computed byte offset. It introduces a symbolic “continuation member offset” node so the importer can reference the eventual offset before the async transformation finalizes the continuation layout, and adds a new JIT↔EE query to resolve the specialized helper method.
Changes:
- Add new CoreLib helpers to await via “awaiter-in-continuation” with an offset, and update suspension handling to call
OnCompleted/UnsafeOnCompletedby reading the awaiter out of the continuation. - Add
GT_CONTINUATION_MEMBER_OFFSETplus continuation-member layout plumbing in the JIT async transformation; update importer to rewrite struct-await helper calls to the new helper and record the member offset. - Extend the JIT↔EE interface and supporting tooling (VM, SuperPMI, ILC/ReadyToRun) to resolve the new helper method; add a regression test covering safe/unsafe custom awaiters.
Reviewed changes
Copilot reviewed 32 out of 32 changed files in this pull request and generated 1 comment.
Show a summary per file
| File | Description |
|---|---|
| src/tests/async/struct/struct.cs | Adds a regression test for safe and unsafe custom struct awaiters under runtime async. |
| src/libraries/System.Private.CoreLib/src/System/Runtime/CompilerServices/AsyncHelpers.cs | Adds new private awaiter-in-continuation helpers and extraction-based OnCompleted/UnsafeOnCompleted paths. |
| src/coreclr/vm/jitinterface.h | Adds VM declaration for the new JIT↔EE query to resolve the awaiter-in-continuation helper. |
| src/coreclr/vm/jitinterface.cpp | Implements helper resolution + runtime lookup computation for the new awaiter-in-continuation call. |
| src/coreclr/vm/corelib.h | Adds CoreLibBinder method IDs for the new AsyncHelpers helper methods. |
| src/coreclr/tools/superpmi/superpmi/icorjitinfo.cpp | Plumbs the new ICorJitInfo method through SuperPMI. |
| src/coreclr/tools/superpmi/superpmi-shim-simple/icorjitinfo_generated.cpp | Updates generated shim to forward the new ICorJitInfo entrypoint. |
| src/coreclr/tools/superpmi/superpmi-shim-counter/icorjitinfo_generated.cpp | Updates generated counter shim to track/forward the new call. |
| src/coreclr/tools/superpmi/superpmi-shim-collector/icorjitinfo.cpp | Updates collector shim to record/replay the new query. |
| src/coreclr/tools/superpmi/superpmi-shared/methodcontext.h | Adds recording/replay declarations and a new packet kind for the query. |
| src/coreclr/tools/superpmi/superpmi-shared/methodcontext.cpp | Implements record/dump/replay for the new query. |
| src/coreclr/tools/superpmi/superpmi-shared/lwmlist.h | Adds LWM map entry for the query. |
| src/coreclr/tools/superpmi/superpmi-shared/agnostic.h | Adds agnostic key struct for recording the query inputs. |
| src/coreclr/tools/Common/JitInterface/ThunkGenerator/ThunkInput.txt | Adds the new API to the JIT interface thunk generator input. |
| src/coreclr/tools/Common/JitInterface/CorInfoImpl.cs | Adds ILC implementation to resolve the new helper method handle. |
| src/coreclr/tools/Common/JitInterface/CorInfoImpl_generated.cs | Adds generated unmanaged callback plumbing for the new API. |
| src/coreclr/tools/aot/jitinterface/jitinterface_generated.h | Updates NativeAOT jitinterface wrapper with the new callback. |
| src/coreclr/tools/aot/ILCompiler.ReadyToRun/Compiler/ReadyToRunCodegenCompilation.cs | Ensures R2R token availability for the new helper methods. |
| src/coreclr/System.Private.CoreLib/src/System/Runtime/CompilerServices/AsyncHelpers.CoreCLR.cs | Adds runtime stack-state fields + dispatcher logic to call awaiter continuation callbacks. |
| src/coreclr/jit/wellknownargs.h | Introduces a new well-known arg kind for the async awaiter pseudo-arg. |
| src/coreclr/jit/importercalls.cpp | Adds importer rewrite to swap struct awaiter calls to the new helper and attach symbolic continuation-member offset. |
| src/coreclr/jit/ICorJitInfo_wrapper_generated.hpp | Adds wrapper method for the new JIT↔EE query. |
| src/coreclr/jit/ICorJitInfo_names_generated.h | Adds the new API name for logging/tracing. |
| src/coreclr/jit/gtstructs.h | Extends GenTreeVal struct mapping to include GT_CONTINUATION_MEMBER_OFFSET. |
| src/coreclr/jit/gtlist.h | Adds the GT_CONTINUATION_MEMBER_OFFSET node kind and documentation. |
| src/coreclr/jit/gentree.cpp | Updates pseudo-arg handling and debug printing for the new node. |
| src/coreclr/jit/compiler.h | Adds compiler state for tracking continuation members and the importer helper prototype. |
| src/coreclr/jit/async.h | Adds continuation-member abstractions and extends layout builder to allocate member offsets. |
| src/coreclr/jit/async.cpp | Implements continuation-member tracking, reserves storage in continuation layouts, and bashes symbolic offsets to constants. |
| src/coreclr/inc/jiteeversionguid.h | Bumps JIT↔EE version GUID due to interface change. |
| src/coreclr/inc/icorjitinfoimpl_generated.h | Adds the new virtual method to the generated ICorJitInfo impl surface. |
| src/coreclr/inc/corinfo.h | Adds the new ICorStaticInfo virtual method for helper resolution. |
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
This optimizes calls to
AsyncHelpers.UnsafeAwaitAwaiterwith struct awaiters to instead call a new functionAsyncHelpers.UnsafeAwaitAwaiterInContinuation(int offset). The idea is that the JIT ensures that the awaiter will be present in the continuation at the specified offset. TheUnsafeOnCompletedcall can then be done without any boxing by extracting it from the continuation.This introduces a new
GT_CONTINUATION_MEMBER_OFFSETwhich is used to solve the linking problem where we do not know the offset into the continuation until much later. The async transformation is responsible for replacing this node with a constant after it knows the offset.I have a couple of use cases for
GT_CONTINUATION_MEMBER_OFFSETin mind, so I have made the mechanism to represent the type of member easily expandable.Fix #119842
Likely still needs ILC scanner work...