Fix NativeAOT resource string inlining for async IL

[jakobbotsch]

Preserve ECMA module identity for async IL wrappers and recognize it when injecting and resolving resource string tokens.

Fix #133954

	Before fix	After fix
Runtime async disabled	1,601,536 bytes	1,601,536 bytes
Runtime async enabled	2,196,480 bytes	1,610,240 bytes

The remaining size difference is coming from

runtime/src/libraries/Common/src/System/Threading/AsyncOverSyncWithIoCancellation.cs

Lines 84 to 86 in 9b84671

	[AsyncMethodBuilder(typeof(PoolingAsyncValueTaskMethodBuilder))]
	[RuntimeAsyncMethodGeneration(false)]
	public static async ValueTask InvokeAsync<TState>(Action<TState> action, TState state, CancellationToken cancellationToken)

which is reachable by the app and which pulls in async1 infrastructure.

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[Copilot]

🔵 Needs a closer look

Add regression coverage for async resource-string inlining and verify the resource is not rooted.

Pull request overview

Fixes NativeAOT resource-string inlining for runtime-async IL by preserving ECMA module identity.

Changes:

• Adds an ECMA-aware async IL wrapper.
• Updates resource token injection and resolution for ECMA-backed IL.

File summaries

File	Summary
src/coreclr/tools/Common/TypeSystem/IL/NativeAotILProvider.cs	Preserves module identity for async IL wrappers.
src/coreclr/tools/aot/ILCompiler.Compiler/Compiler/SubstitutedILProvider.cs	Enables resource-string token handling for ECMA-backed async IL.

Review details

Suppressed comments (2)

src/coreclr/tools/Common/TypeSystem/IL/NativeAotILProvider.cs:374

• Could you add a NativeAOT regression test that exercises a real runtime-async method containing an SR resource-property access? The existing FrameworkStrings coverage only exercises resource-string substitution from synchronous IL, so it would still pass if this wrapper failed to preserve its ECMA module. The assertion should verify the resource is not rooted (or inspect the resulting size/dependency output), not only that the async call returns the expected string, since the old implementation can still return the value by retaining the resource.

                return wrappedIL is EcmaMethodIL ecmaIL
                    ? new EcmaAsyncMethodIL(asyncVariantImpl, ecmaIL)
                    : new AsyncMethodIL(asyncVariantImpl, wrappedIL);

src/coreclr/tools/aot/ILCompiler.Compiler/Compiler/SubstitutedILProvider.cs:635

• Please add a NativeAOT regression test for this path. The existing runtime-async tests do not exercise SubstitutedILProvider's resource-string inlining, so a future regression in the async wrapper's ECMA-module identity or injected-token resolution could recreate the size/rooting issue without failing tests. The test should compile an async method containing a generated SR accessor and verify that the accessor is inlined and its resource is not rooted.

[!NOTE]
This review comment was created by GitHub Copilot.

            if (hasGetResourceStringCall && method.GetMethodILDefinition() is IEcmaMethodIL ecmaMethodIL)

• Files reviewed: 2/2 changed files
• Comments generated: 0
• Review effort level: Lite

[jakobbotsch]

/backport to release/11.0

[github-actions]

Started backporting to release/11.0 (link to workflow run)