[clang] [llvm] [HLSL][RootSignature] Implement parsing of a DescriptorTable with empty clauses (PR #133302)

[Justin Bogner via llvm-commits]

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@@ -0,0 +1,188 @@
+#include "clang/Parse/ParseHLSLRootSignature.h"
+
+#include "llvm/Support/raw_ostream.h"
+
+using namespace llvm::hlsl::rootsig;
+
+namespace clang {
+namespace hlsl {
+
+static std::string FormatTokenKinds(ArrayRef<TokenKind> Kinds) {
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bogner wrote:

You can simplify this while also making it more efficient by implementing a `TokenFormatter` class with an `operator<<`  for `DiagnosticBuilder`. The class should be okay to hold an `ArrayRef` as a member since it will always be used as a temporary, like `DB << TokenFormatter(Tokens);`

https://github.com/llvm/llvm-project/pull/133302