--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/clang-tools-extra/clang-doc/Generators.h	Thu Feb 13 15:10:13 2020 +0900
@@ -0,0 +1,52 @@
+//===-- Generators.h - ClangDoc Generator ----------------------*- 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
+//
+//===----------------------------------------------------------------------===//
+// Generator classes for converting declaration information into documentation
+// in a specified format.
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_TOOLS_EXTRA_CLANG_DOC_GENERATOR_H
+#define LLVM_CLANG_TOOLS_EXTRA_CLANG_DOC_GENERATOR_H
+
+#include "Representation.h"
+#include "llvm/Support/Error.h"
+#include "llvm/Support/Registry.h"
+
+namespace clang {
+namespace doc {
+
+// Abstract base class for generators.
+// This is expected to be implemented and exposed via the GeneratorRegistry.
+class Generator {
+public:
+  virtual ~Generator() = default;
+
+  // Write out the decl info in the specified format.
+  virtual llvm::Error generateDocForInfo(Info *I, llvm::raw_ostream &OS,
+                                         const ClangDocContext &CDCtx) = 0;
+  // This function writes a file with the index previously constructed.
+  // It can be overwritten by any of the inherited generators.
+  // If the override method wants to run this it should call
+  // Generator::createResources(CDCtx);
+  virtual llvm::Error createResources(ClangDocContext &CDCtx);
+
+  static void addInfoToIndex(Index &Idx, const doc::Info *Info);
+};
+
+typedef llvm::Registry<Generator> GeneratorRegistry;
+
+llvm::Expected<std::unique_ptr<Generator>>
+findGeneratorByName(llvm::StringRef Format);
+
+std::string getAccess(AccessSpecifier AS);
+
+std::string getTagType(TagTypeKind AS);
+
+} // namespace doc
+} // namespace clang
+
+#endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_DOC_GENERATOR_H