[llvm] [llvm][MC] Fix missing SubArch information when calling lookupTarget (PR #69902)

[Jessica Clarke via llvm-commits]

jrtc27 wrote:

What if the subarch doesn't make sense for the new arch? The only test here seems to be doing a redundant setArch to the same as getArch already returns, which isn't an overly compelling use case. I don't think you want mips64r6 to turn into aarch64r6 when you do a setArch, for example?..

https://github.com/llvm/llvm-project/pull/69902