[cDAC][wasm] Native code addresses for portable entry points are not mapped to interpreter code or R2R virtual IPs

[lewing]

Description

On FEATURE_PORTABLE_ENTRYPOINTS targets (currently WebAssembly), a method's entry point slot holds a PortableEntryPoint address. The native runtime maps that address to a resolvable code start before handing it to diagnostics:

• GetInterpreterCodeFromEntryPointIfPresent (src/coreclr/vm/precode.cpp) returns the interpreter bytecode for interpreted methods.
• GetDiagnosticCodeStartFromEntryPoint (same file, shared by EventPipe method events and RuntimeMethodHandle_GetNativeCode) additionally maps native R2R portable entry points, whose actual code is a function-table index, to the synthetic virtual IP registered through ExecutionManager::AddVirtualIPRange.

The cDAC does neither:

• RuntimeTypeSystem_1.GetNativeCode returns the raw entry-point slot value.
• PrecodeStubs_1.GetInterpreterCodeFromInterpreterPrecodeIfPresent only recognizes interpreter StubPrecodes and has no portable-entry-point case, so it returns the PortableEntryPoint address unchanged.

As a result, SOS method data such as DacpMethodDescData.NativeCodeAddr and rejit NativeCodeAddr (SOSDacImpl.cs) should report a PortableEntryPoint address on wasm for both interpreted and R2R methods. That address does not resolve through ExecutionManager lookups (GetCodeBlockHandle, FindVirtualIPRangeSection).

This was found by code inspection while fixing #134145. It has not been reproduced against a live wasm target.

Suggested direction

When the portable-entrypoints feature flag is enabled, mirror the native mapping for a portable entry point:

1. If the method has interpreter code, return the bytecode start.
2. Otherwise, if it has a native entry point, map the function-table index to its virtual IP. Use FunctionTableIndexRangeSection data (already read by the wasm stack walk), the owning ReadyToRunInfo.MinVirtualIP, and the containing non-funclet RUNTIME_FUNCTION, matching ExecutionManager::GetWasmVirtualIPFromFunctionTableIndex.

The pieces are already exposed: Data.PortableEntryPoint (used by NonVirtualEntry2MethodDesc), FunctionTableIndexRangeSection, and the virtual-IP range list added in #133917. The contract docs under docs/design/datacontracts would need a matching update.

Note

This issue was drafted with GitHub Copilot.

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[lewing]

fix in #134756