Co-authored-by: Jeff Schwartz <jeffschw@microsoft.com>

…107780)

* Remove entry of APIs because of #103297

* comment out the test cases for unsupported APIs

Co-authored-by: Jeff Schwartz <jeffschw@microsoft.com>

- Use `TypeHandle::CanCastTo` instead of `MethodTable::CanCastTo`
  - The issue is that the `MethodTable` api requires cooperative mode, and the `TypeHandle` supports either mode

Fixes #107754

Co-authored-by: David Wrighton <davidwr@microsoft.com>
Co-authored-by: Jeff Schwartz <jeffschw@microsoft.com>

…ds (#105521)" (#107712)

* Partially  revert "[GC] Avoid OOM in large-allocation-only workloads (#105521)"

This partially reverts commit b27a808.

This is done instead of a full revert because there were merge conflicts
with bfb674e.  This also minimizes diffs with main in case of future
backports.

This reverts the distribute_free_regions but keeps the factoring.  It also
keeps the aging of huge free regions, but nothing is done with those ages.

* Revert more of "[GC] Avoid OOM in large-allocation-only workloads (#105521)"

This reverts the rest of commit b27a808
except for the age helper.

---------

Co-authored-by: Jeff Schwartz <jeffschw@microsoft.com>

…ClassInitThrowing` didn't check to see if the class had been initialized before taking a lock - `EnsureTlsIndexAllocated` didn't check if the Tls index had been allocated before setting the flag via an expensive Interlocked call to indicate that it had been allocated - And finally `JIT_GetNonGCThreadStaticBaseOptimized` and `JIT_GetGCThreadStaticBaseOptimized` were missing the fast paths which avoided even calling those apis at all. (#107817)

Perf with a small benchmark which does complex multithreaded work...

| Runtime | Time |
| ---- | ---- |
| .NET 8 | 00.9414682 s |
| .NET 9 before this fix |  22.8079382 |
| .NET 9 with this fix | 00.2004539 |

Fixes #107728

Co-authored-by: David Wrighton <davidwr@microsoft.com>