Delete LOADEDMODULES cache

[jkotas]

This cache is not used by the runtime and it is not compiled into debugger (mscordbi). It looks like a left-over from fusion.

[Copilot]

Pull Request Overview

This pull request removes the LOADEDMODULES cache and all associated caching logic, as it is no longer used by the runtime or debugger. Key changes include:

• Eliminating calls to AddToCache across multiple modules and functions.
• Removing the LOADEDMODULES class and the regmeta_vm.cpp file.
• Updating RegMeta methods (e.g., Release and ResolveTypeRef) to simplify implementation by removing cache handling.

Reviewed Changes

Copilot reviewed 11 out of 11 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
src/coreclr/md/enc/mdinternalrw.cpp	Removed AddToCache call as part of deprecating caching logic.
src/coreclr/md/compiler/regmeta_vm.cpp	Deleted obsolete file containing LOADEDMODULES cache logic.
src/coreclr/md/compiler/regmeta_import.cpp	Updated ResolveTypeRef to return E_NOTIMPL, deprecating cache use.
src/coreclr/md/compiler/regmeta.h	Removed declarations for caching methods and members.
src/coreclr/md/compiler/regmeta.cpp	Simplified Release implementation, removing cache-related checks.
src/coreclr/md/compiler/mdutil.h	Removed LOADEDMODULES class and associated functions.
src/coreclr/md/compiler/emit.cpp	Updated DefineSecurityAttributeSet to return E_NOTIMPL.
src/coreclr/md/compiler/disp.cpp	Removed multiple AddToCache calls, eliminating cache lookup logic.
src/coreclr/md/compiler/assemblymd.cpp	Removed unused code related to caching.
src/coreclr/md/compiler/CMakeLists.txt	Removed regmeta_vm.cpp from the build, as it is no longer needed.

Comments suppressed due to low confidence (3)

src/coreclr/md/compiler/disp.cpp:182

• The removal of the cached RegMeta lookup in the read-only path means that every open call creates a new instance; please confirm that this change does not adversely impact performance or memory usage.

if (IsOfReadOnly(dwOpenFlags) && IsOfReadWrite(dwOpenFlags)) {   // Invalid combination of flags - ofReadOnly & ofWrite

src/coreclr/md/compiler/regmeta.cpp:524

• The updated Release method now simply deletes the instance when the reference count reaches zero. Please verify that all concurrent usage scenarios have been adjusted to account for the removal of cache-specific lifetime management.

ULONG RegMeta::Release() { ULONG cRef = InterlockedDecrement(&m_cRef);

src/coreclr/md/compiler/regmeta_import.cpp:831

• Since ResolveTypeRef now returns E_NOTIMPL, please ensure that clients calling this API have been updated to handle this deprecation appropriately.

return E_NOTIMPL;

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[huoyaoyuan]

The caching logic for CLiteWeightStgdbRW::m_dwDatabaseLFT/m_dwDatabaseLFS in CLiteWeightStgdbRW::OpenForRead can also be removed. However, I'm unsure whether the copy logic at Target_CLiteWeightStgdbRW::ReadFrom has impact.

[AaronRobinsonMSFT]

[AaronRobinsonMSFT]

@jkotas Do you know what FEATURE_METADATA_IN_VM is intended for?

[jkotas]

Do you know what FEATURE_METADATA_IN_VM is intended for?

IMetadata... interface implementations are compiled into multiple binaries, with different features. The flavor compiled into coreclr.dll has one set of features, the flavor compiled into mscordbi.dll has different set of features. We used to have even more flavors in .NET Framework.

FEATURE_METADATA_IN_VM controls features of the coreclr.dll flavor. The only feature left after this cleanup is a free threaded marshaller . I am thinking we can delete it too.