What's the status of x64 emulation effort?

[riverar]

After reading the following issues, it's unclear what the status of this effort is. If it's complete, it's not clear how to use it (other than rearranging dotnet paths). cc: @richlander

• RFC: dotnet [Arm64 | x64] coexistence #16896
• Supporting .NET with x64 emulation on Arm64 #17463
• x64 emulation model #17464
• Add plan for x64 emulation designs#217

[dotnet-issue-labeler]

I couldn't figure out the best area label to add to this issue. If you have write-permissions please help me learn by adding exactly one area label.

[marcpopMSFT]

X64 runtimes and SDKs are now installed under sub-paths of the normal dotnet folder. They are not automatically added to the path so to use that SDK, you have to add that to the path. To use those runtimes, I believe you have to set DOTNET_ROOT_X64. @richlander would know if there are any docs outlining process besides his existing design docs: https://github.com/dotnet/designs/blob/main/accepted/2021/x64-emulation-on-arm64/x64-emulation.md