[llvm] [AMDGPU][GlobalIsel] Introduce isRegType to check for legal types, instead of checking bit width. (PR #68189)

[via llvm-commits]

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@@ -299,129 +299,6 @@ body: |
     S_NOP 0, implicit %12
 ...
 ---
-name: legal_v13s32
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sstipanovic wrote:

Because these are not legal anymore

https://github.com/llvm/llvm-project/pull/68189