Make it possible to preinitialize ComInterfaceEntry

[MichalStrehovsky]

Fixes #114355.

Special case ComWrappers.ComInterfaceEntry and types that only consist of these fields to achieve this.

Cc @dotnet/ilc-contrib @Sergio0694

[Copilot]

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

Comments suppressed due to low confidence (3)

src/coreclr/tools/aot/ILCompiler.Compiler/Compiler/TypePreinit.cs:2705

• In the Clone method of VTableLikeStructValue (line 2705), passing null for fieldThatOwnsMemory may cause loss of necessary context. Consider preserving the existing fieldThatOwnsMemory if applicable.

return new VTableLikeStructValue(_type, (MethodDesc[])_methods.Clone(), fieldThatOwnsMemory: null);

src/coreclr/tools/aot/ILCompiler.Compiler/Compiler/TypePreinit.cs:2727

• The MemoryOwner property in VTableLikeSlotReferenceValue returns a non-null value only when _index is 0. Verify that this behavior is intentional for all indices.

public override FieldDesc MemoryOwner => _index == 0 ? _fieldThatOwnsMemory : null;

src/coreclr/tools/aot/ILCompiler.Compiler/Compiler/TypePreinit.cs:2491

• In the IsCompatible method of ComInterfaceEntryArrayValue, entryType is overwritten for each non-static field without verifying that all fields share the same ComInterfaceEntry type. Consider adding an explicit check to ensure consistency across all instance fields.

foreach (FieldDesc field in type.GetFields()) { ... entryType = field.FieldType; ... }

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[Sergio0694]

Looks great!! Example use in CsWinRT 3.0 (assuming #114455 too), for reference: here 🙂