[llvm] [DirectX] Error handling improve in root signature metadata Parser (PR #149232)

[Chris B via llvm-commits]

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@@ -182,16 +176,15 @@ MDNode *MetadataBuilder::BuildDescriptorTableClause(
     const DescriptorTableClause &Clause) {
   IRBuilder<> Builder(Ctx);
   std::optional<StringRef> ResName =
-      getResourceName(dxil::ResourceClass(llvm::to_underlying(Clause.Type)));
+      getResourceName(dxil::ResourceClass(to_underlying(Clause.Type)));
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llvm-beanz wrote:

We could also add a new version of `enumToString` that returned `StringRef` instead of `std::string` and had a null-string as the sentinel for "no match". That would have the benefit of avoiding allocating a `std::string`.

https://github.com/llvm/llvm-project/pull/149232