[clang] [llvm] [HLSL][RootSignature] Implement parsing of `RootFlags` (PR #121799)

[Finn Plummer via llvm-commits]

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@@ -0,0 +1,88 @@
+//===- HLSLRootSignature.h - HLSL Root Signature helper objects -----------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file This file contains helper objects for working with HLSL Root
+/// Signatures.
+///
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_FRONTEND_HLSL_HLSLROOTSIGNATURE_H
+#define LLVM_FRONTEND_HLSL_HLSLROOTSIGNATURE_H
+
+#include <stdint.h>
+
+#include "llvm/Support/Endian.h"
+
+namespace llvm {
+namespace hlsl {
+namespace root_signature {
+
+// This is a copy from DebugInfo/CodeView/CodeView.h
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inbelic wrote:

This macro is defined as there will be additional `enum class` flags that will require this as well. We don't necessarily use the operators, so we could also manually define only the ones used. Or we can move the debuginfo version into a common header?

https://github.com/llvm/llvm-project/pull/121799