[clang] Implement resource binding type prefix mismatch errors (PR #87578)

[Chris B via cfe-commits]

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@@ -7403,41 +7403,36 @@ static void handleHLSLResourceBindingAttr(Sema &S, Decl *D,
     }
     switch (RC) {
     case llvm::hlsl::ResourceClass::SRV: {
-      if (Slot.substr(0, 1) != "t")
+      if (Slot[0] != 't')
         S.Diag(ArgLoc, diag::err_hlsl_mismatching_register_type_and_name)
             << Slot.substr(0, 1) << varTy << "t";
       break;
     }
     case llvm::hlsl::ResourceClass::UAV: {
-      if (Slot.substr(0, 1) != "u")
+      if (Slot[0] != 'u')
         S.Diag(ArgLoc, diag::err_hlsl_mismatching_register_type_and_name)
             << Slot.substr(0, 1) << varTy << "u";
       break;
     }
     case llvm::hlsl::ResourceClass::CBuffer: {
-      if (Slot.substr(0, 1) != "b")
+      if (Slot[0] != 'b')
         S.Diag(ArgLoc, diag::err_hlsl_mismatching_register_type_and_name)
             << Slot.substr(0, 1) << varTy << "b";
       break;
     }
     case llvm::hlsl::ResourceClass::Sampler: {
-      if (Slot.substr(0, 1) != "s")
+      if (Slot[0] != 's')
         S.Diag(ArgLoc, diag::err_hlsl_mismatching_register_type_and_name)
             << Slot.substr(0, 1) << varTy << "s";
       break;
     }
-    case llvm::hlsl::ResourceClass::Invalid: {
+    default: {
----------------
llvm-beanz wrote:

It would be better to have this be the Invalid case. Then the compiler will warn if new enum values get added that aren't handled.

https://github.com/llvm/llvm-project/pull/87578