[clang] [HLSL][RootSignature] Implement Lexing of DescriptorTables (PR #122981)

[Finn Plummer via cfe-commits]

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@@ -0,0 +1,96 @@
+//===--- ParseHLSLRootSignature.h -------------------------------*- C++ -*-===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+//
+//  This file defines the ParseHLSLRootSignature interface.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_PARSE_PARSEHLSLROOTSIGNATURE_H
+#define LLVM_CLANG_PARSE_PARSEHLSLROOTSIGNATURE_H
+
+#include "clang/Lex/LiteralSupport.h"
+#include "clang/Lex/Preprocessor.h"
+
+#include "llvm/ADT/APInt.h"
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/ADT/StringRef.h"
+#include "llvm/ADT/StringSwitch.h"
+
+namespace llvm {
+namespace hlsl {
+namespace root_signature {
+
+struct RootSignatureToken {
+  enum Kind {
+#define TOK(X) X,
+#include "clang/Parse/HLSLRootSignatureTokenKinds.def"
+  };
+
+  Kind Kind = Kind::invalid;
+
+  // Retain the SouceLocation of the token for diagnostics
+  clang::SourceLocation TokLoc;
+
+  // Retain if the uint32_t bits represent a signed integer
+  bool Signed = false;
+  union {
+    uint32_t IntLiteral = 0;
+    float FloatLiteral;
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inbelic wrote:

Yep, good idea

https://github.com/llvm/llvm-project/pull/122981