[llvm] [AMDGPU][GlobalISel] Add RegBankLegalize rules for TFE buffer loads (PR #179529)

[Matt Arsenault via llvm-commits]

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@@ -1181,6 +1181,11 @@ LLT RegBankLegalizeHelper::getBTyFromID(RegBankLLTMappingApplyID ID, LLT Ty) {
         isAnyPtr(Ty, 128))
       return Ty;
     return LLT();
+  case VgprB160:
+  case UniInVgprB160:
+    if (Ty == LLT::scalar(160) || Ty == LLT::fixed_vector(5, 32))
+      return Ty;
+    return LLT();
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arsenm wrote:

What is the point of this function? It seems to just be checking if the type is legal, except it's going to require a whole lot of updating when LLT gains different FP types 

https://github.com/llvm/llvm-project/pull/179529