Enable R2R for unresolved static virtual interface calls

[jkoritzinsky]

Summary

Enable Crossgen2 to compile unresolved constrained static virtual interface calls that require a runtime lookup.

The lookup now:

• uses CORINFO_CALL_CODE_POINTER so the computed runtime lookup is preserved
• encodes a ConstrainedMethodEntrySlot with the runtime-determined constraint
• suppresses the hidden instantiation argument expected by a normal shared-generic callsite

This allows System.RuntimeType+IGenericCacheEntry<TCache>.CreateAndCache to be emitted as R2R code instead of falling back to runtime JIT compilation.

Fixes #120405

Testing

• dotnet.cmd build src/coreclr/tools/aot/crossgen2/crossgen2.csproj -c Debug --no-restore
• Compiled IGenericCacheEntry<ActivatorCache>.CreateAndCache in Crossgen2 single-method mode
• Verified with R2RDump that Create and GetStorageRef use constrained lookups against var #0, not System.__Canon, followed by indirect calls
• Ran the CoreCLR StaticVirtualMethods loader suite successfully

Note

This pull request description was generated by GitHub Copilot.

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[Copilot]

Pull request overview

Enable Crossgen2 (ReadyToRun JIT interface) to R2R-compile unresolved constrained static virtual interface calls that require an exact-context runtime lookup, instead of bailing out to runtime JIT.

Changes:

• Replace the RequiresRuntimeJitException for exactContextNeedsRuntimeLookup unresolved constrained SVM calls with a CORINFO_CALL_CODE_POINTER + runtime lookup path.
• Use DictionaryEntryKind.ConstrainedMethodEntrySlot for the runtime lookup and request an instantiating stub (suppress hidden instantiation argument at the callsite).

[jkoritzinsky]

/azp run runtime-coreclr crossgen2 outerloop

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[jkoritzinsky]

/azp run runtime-coreclr crossgen2-composite gcstress

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Azure Pipelines:
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[Copilot]

Pull request overview

Copilot reviewed 1 out of 1 changed files in this pull request and generated no new comments.

[davidwrighton]

@jkoritzinsky Have you validated what happens when a case where the structure doesn't implement the interface method, but it is implemented by a default implementation on the interface?

[jkoritzinsky]

In https://dev.azure.com/dnceng-public/public/_build/results?buildId=1524294&view=logs&jobId=c7387c70-b93d-5740-226d-f0ff8a1214f4 (from f16965a, the first commit in this PR), I ran all the src/tests tree under ReadyToRun, so that should be covered by the StructWithDIM case in the StaticVirtualDIMOnReferenceType test suite.

[jkoritzinsky]

/ba-g failure is only in NAOT and this code is only in R2R