Adding GetAssemblyLoadContext cDAC API

[rcj1]

No description provided.

[Copilot]

Pull Request Overview

This PR adds support for retrieving Assembly Load Context (ALC) information through the cDAC API by implementing the GetAssemblyLoadContext method. The implementation provides a way to traverse from a method table to its associated Assembly Load Context by following the chain: MethodTable → Module → PEAssembly → HostAssembly/FallbackBinder → AssemblyBinder → ManagedAssemblyLoadContext.

Key changes include:

• Implementation of GetAssemblyLoadContext method in SOSDacImpl.cs with proper error handling and debug validation
• Addition of new data structures (BinderSpaceAssembly, AssemblyBinder) to support ALC traversal
• Extension of existing data structures (PEAssembly) with additional fields for binder information
• Addition of GetBinderAssemblyLoadContext method to the ILoader contract

Reviewed Changes

Copilot reviewed 12 out of 12 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
SOSDacImpl.cs	Implements GetAssemblyLoadContext method with cDAC contract calls and debug validation
PEAssembly.cs	Adds HostAssembly and FallbackBinder fields to support ALC traversal
BinderSpaceAssembly.cs	New data structure representing binder space assembly with Binder field
AssemblyBinder.cs	New data structure representing assembly binder with ManagedAssemblyLoadContext field
Loader_1.cs	Implements GetBinderALC method to traverse ALC hierarchy
DataType.cs	Adds enum entries for new data types
ILoader.cs	Adds GetBinderAssemblyLoadContext method to interface
peassembly.h	Adds cdac_data template specialization with new field offsets
assemblybinder.h	Adds cdac_data template specialization and friend declaration
datadescriptor.h	Adds CDAC type definitions for new data structures
assembly.hpp	Adds cdac_data template specialization for BINDER_SPACE::Assembly
Loader.md	Updates documentation with new API and data structure descriptions

Comments suppressed due to low confidence (2)

src/native/managed/cdac/Microsoft.Diagnostics.DataContractReader.Contracts/Contracts/Loader_1.cs:298

• The method name 'GetBinderALC' is inconsistent with the interface method name 'GetBinderAssemblyLoadContext'. The implementation should match the interface method name for clarity.

    TargetPointer ILoader.GetBinderALC(ModuleHandle handle)

src/native/managed/cdac/mscordaccore_universal/Legacy/SOSDacImpl.cs:946

• The code calls 'GetBinderAssemblyLoadContext' but the actual implementation method is named 'GetBinderALC', which will cause a runtime error due to the method name mismatch.

            // which is apparently not expected by SOS.

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[jkotas]

LGTM. Thank you!

@max-charlamb Could you please review this as well?

• There is a merge conflict to resolve
• It would be nice to rename ManagedAssemblyLoadContext -> AssemblyLoadContext everywhere as mentioned above (in a separate PR)

[max-charlamb]

lgtm mod one small nit 👍

[jkotas]

/ba-g System.Collections.Tests failure is knonw issue #117939