[llvm] [AMDGPU][GlobalIsel] Use isRegisterClassType to check for legal types for G_FREEZE & G_IMPLICIT_DEF (PR #101331)

[Matt Arsenault via llvm-commits]

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@@ -186,23 +184,6 @@ body: |
     %1:_(s32) = G_LOAD %0 :: (load (s32) from %ir.tmp1)
 ...
 
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-name: non_power_of_2
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arsenm wrote:

Why was this deleted? 

https://github.com/llvm/llvm-project/pull/101331