[clang] [HLSL] Collect explicit resource binding information (PR #111203)

[Helena Kotas via cfe-commits]

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@@ -4593,6 +4593,44 @@ def HLSLResourceBinding: InheritableAttr {
   let LangOpts = [HLSL];
   let Args = [StringArgument<"Slot">, StringArgument<"Space", 1>];
   let Documentation = [HLSLResourceBindingDocs];
+  let AdditionalMembers = [{
+      enum class RegisterType : unsigned { SRV, UAV, CBuffer, Sampler, C, I, Invalid };
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hekota wrote:

This enum is just moved from SemaHLSL but yeah, there is no reason to keep the Invalid value here. It is only used when validating the register letter.

https://github.com/llvm/llvm-project/pull/111203