[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 +1,110 @@
+//===--- 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/Basic/DiagnosticParse.h"
+#include "clang/Lex/LexHLSLRootSignature.h"
+#include "clang/Lex/Preprocessor.h"
+
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/ADT/StringRef.h"
+
+#include "llvm/Frontend/HLSL/HLSLRootSignature.h"
+
+namespace clang {
+namespace hlsl {
+
+class RootSignatureParser {
+public:
+  RootSignatureParser(SmallVector<llvm::hlsl::rootsig::RootElement> &Elements,
+                      RootSignatureLexer &Lexer, clang::Preprocessor &PP);
+
+  /// Consumes tokens from the Lexer and constructs the in-memory
+  /// representations of the RootElements. Tokens are consumed until an
+  /// error is encountered or the end of the buffer.
+  ///
+  /// Returns true if a parsing error is encountered.
+  bool Parse();
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bogner wrote:

Since this is all new code we should use the LLVM naming conventions for methods of starting with lower case, rather than matching the legacy conventions elsewhere in the `Parse` library. https://llvm.org/docs/CodingStandards.html#name-types-functions-variables-and-enumerators-properly

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