[llvm] [ValueTypes][NFC] Generate EVT::getTypeForEVT from GenVT.inc (PR #96608)

[Kito Cheng via llvm-commits]

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@@ -14,6 +14,7 @@
 class ValueType<int size, int value> {
   string Namespace = "MVT";
   string LLVMName = NAME;
+  string LLVMTy = "";
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kito-cheng wrote:

This only used for floating point types, part of floating point type can  inference from other fields , but some of them like bf16, ppc f128 and x86 fp80 can't, and bf16 will used by vector types, so I think keep an optional LLVMTy field should be easier to maintain here.

https://github.com/llvm/llvm-project/pull/96608