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diff --git a/clang/include/clang/AST/AttrVisitor.h b/clang/include/clang/AST/AttrVisitor.h
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index 00000000000..867f9e7ad18
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+++ b/clang/include/clang/AST/AttrVisitor.h
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+//===- AttrVisitor.h - Visitor for Attr subclasses --------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+//  This file defines the AttrVisitor interface.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_AST_ATTRVISITOR_H
+#define LLVM_CLANG_AST_ATTRVISITOR_H
+
+#include "clang/AST/Attr.h"
+
+namespace clang {
+
+namespace attrvisitor {
+
+/// A simple visitor class that helps create attribute visitors.
+template <template <typename> class Ptr, typename ImplClass,
+          typename RetTy = void, class... ParamTys>
+class Base {
+public:
+#define PTR(CLASS) typename Ptr<CLASS>::type
+#define DISPATCH(NAME)                                                         \
+  return static_cast<ImplClass *>(this)->Visit##NAME(static_cast<PTR(NAME)>(A))
+
+  RetTy Visit(PTR(Attr) A) {
+    switch (A->getKind()) {
+
+#define ATTR(NAME)                                                             \
+  case attr::NAME:                                                             \
+    DISPATCH(NAME##Attr);
+#include "clang/Basic/AttrList.inc"
+    }
+    llvm_unreachable("Attr that isn't part of AttrList.inc!");
+  }
+
+  // If the implementation chooses not to implement a certain visit
+  // method, fall back to the parent.
+#define ATTR(NAME)                                                             \
+  RetTy Visit##NAME##Attr(PTR(NAME##Attr) A) { DISPATCH(Attr); }
+#include "clang/Basic/AttrList.inc"
+
+  RetTy VisitAttr(PTR(Attr)) { return RetTy(); }
+
+#undef PTR
+#undef DISPATCH
+};
+
+} // namespace attrvisitor
+
+/// A simple visitor class that helps create attribute visitors.
+///
+/// This class does not preserve constness of Attr pointers (see
+/// also ConstAttrVisitor).
+template <typename ImplClass, typename RetTy = void, typename... ParamTys>
+class AttrVisitor : public attrvisitor::Base<std::add_pointer, ImplClass, RetTy,
+                                             ParamTys...> {};
+
+/// A simple visitor class that helps create attribute visitors.
+///
+/// This class preserves constness of Attr pointers (see also
+/// AttrVisitor).
+template <typename ImplClass, typename RetTy = void, typename... ParamTys>
+class ConstAttrVisitor
+    : public attrvisitor::Base<llvm::make_const_ptr, ImplClass, RetTy,
+                               ParamTys...> {};
+
+} // namespace clang
+
+#endif // LLVM_CLANG_AST_ATTRVISITOR_H