Adding GetMethodTableFieldData cDAC API

[rcj1]

No description provided.

[Copilot]

Pull Request Overview

This PR introduces the GetMethodTableFieldData cDAC API, adds the corresponding data structures and mappings, and updates contracts, metadata layouts, and documentation to support querying instance, static, and thread-static field information from a MethodTable.

• Implemented GetMethodTableFieldData in SOSDacImpl with debug-only consistency checks against legacy DAC.
• Added DacpMethodTableFieldData struct to the interface and propagated new field descriptors through the data contracts, runtime type system, native layout, and documentation.
• Updated contracts (EEClass, IRuntimeTypeSystem, RuntimeTypeSystem_1), coreclr headers (class.h, methodtable.h, datadescriptor.h), and design docs.

Reviewed Changes

Copilot reviewed 9 out of 9 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
src/native/managed/cdac/mscordaccore_universal/Legacy/SOSDacImpl.cs	Added implementation of GetMethodTableFieldData
src/native/managed/cdac/mscordaccore_universal/Legacy/ISOSDacInterface.cs	Defined DacpMethodTableFieldData struct
src/native/managed/cdac/Microsoft.Diagnostics.DataContractReader.Contracts/Data/EEClass.cs	Extended EEClass data contract with new field counts and list
src/native/managed/cdac/Microsoft.Diagnostics.DataContractReader.Contracts/Contracts/RuntimeTypeSystem_1.cs	Added field-related query methods (GetNum*Fields, GetFieldDescList, etc.)
src/native/managed/cdac/Microsoft.Diagnostics.DataContractReader.Abstractions/Contracts/IRuntimeTypeSystem.cs	Declared new field-related methods in the runtime type system interface
src/coreclr/vm/methodtable.h	Minor cleanup (removed extra blank line)
src/coreclr/vm/class.h	Added offset constants for new EEClass fields
src/coreclr/debug/runtimeinfo/datadescriptor.h	Added CDAC_TYPE_FIELD entries for new EEClass fields
docs/design/datacontracts/RuntimeTypeSystem.md	Updated documentation and data descriptor tables for new fields

Comments suppressed due to low confidence (3)

src/native/managed/cdac/mscordaccore_universal/Legacy/SOSDacImpl.cs:952

• This newly added API lacks any unit or integration tests. Please add tests covering types with instance, static, and thread-static fields to verify the behavior.

    int ISOSDacInterface.GetMethodTableFieldData(ClrDataAddress mt, void* data)

docs/design/datacontracts/RuntimeTypeSystem.md:380

• The parameter name 'TypeHandle' shadows the type and uses incorrect casing. Rename it to 'typeHandle' and update references in the method body to avoid confusion.

    public TargetPointer GetModule(TypeHandle TypeHandle)

src/native/managed/cdac/mscordaccore_universal/Legacy/ISOSDacInterface.cs:139

• [nitpick] Remove the trailing semicolon after the struct declaration to match C# style and maintain consistency with other struct definitions in this file.

};

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[max-charlamb]

Actual implementation logic looks good. Good work on adding the datadescriptors 👍

Comments mostly on moving around of fields in RTS contract.

[max-charlamb]

This should be good to merge after fixing the one comment