Index: include/clang/AST/ASTDumper.h
===================================================================
--- /dev/null
+++ include/clang/AST/ASTDumper.h
@@ -0,0 +1,56 @@
+//===--- ASTDumper.h - Dumping implementation for ASTs --------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_AST_ASTDUMPER_H
+#define LLVM_CLANG_AST_ASTDUMPER_H
+
+#include "clang/AST/ASTNodeTraverser.h"
+#include "clang/AST/TextNodeDumper.h"
+
+namespace clang {
+
+class ASTDumper : public ASTNodeTraverser<ASTDumper, TextNodeDumper> {
+
+  TextNodeDumper NodeDumper;
+
+  raw_ostream &OS;
+
+  const bool ShowColors;
+
+public:
+  ASTDumper(raw_ostream &OS, const comments::CommandTraits *Traits,
+            const SourceManager *SM)
+      : ASTDumper(OS, Traits, SM, SM && SM->getDiagnostics().getShowColors()) {}
+
+  ASTDumper(raw_ostream &OS, const comments::CommandTraits *Traits,
+            const SourceManager *SM, bool ShowColors)
+      : ASTDumper(OS, Traits, SM, ShowColors, LangOptions()) {}
+  ASTDumper(raw_ostream &OS, const comments::CommandTraits *Traits,
+            const SourceManager *SM, bool ShowColors,
+            const PrintingPolicy &PrintPolicy)
+      : NodeDumper(OS, ShowColors, SM, PrintPolicy, Traits), OS(OS),
+        ShowColors(ShowColors) {}
+
+  TextNodeDumper &doGetNodeDelegate() { return NodeDumper; }
+
+  void dumpLookups(const DeclContext *DC, bool DumpDecls);
+
+  template <typename SpecializationDecl>
+  void dumpTemplateDeclSpecialization(const SpecializationDecl *D,
+                                      bool DumpExplicitInst, bool DumpRefOnly);
+  template <typename TemplateDecl>
+  void dumpTemplateDecl(const TemplateDecl *D, bool DumpExplicitInst);
+
+  void VisitFunctionTemplateDecl(const FunctionTemplateDecl *D);
+  void VisitClassTemplateDecl(const ClassTemplateDecl *D);
+  void VisitVarTemplateDecl(const VarTemplateDecl *D);
+};
+
+} // clang
+
+#endif
Index: lib/AST/ASTDumper.cpp
===================================================================
--- lib/AST/ASTDumper.cpp
+++ lib/AST/ASTDumper.cpp
@@ -11,10 +11,9 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include "clang/AST/ASTDumper.h"
 #include "clang/AST/ASTContext.h"
-#include "clang/AST/ASTNodeTraverser.h"
 #include "clang/AST/DeclLookups.h"
-#include "clang/AST/TextNodeDumper.h"
 #include "clang/Basic/Builtins.h"
 #include "clang/Basic/Module.h"
 #include "clang/Basic/SourceManager.h"
@@ -22,50 +21,6 @@
 using namespace clang;
 using namespace clang::comments;
 
-//===----------------------------------------------------------------------===//
-// ASTDumper Visitor
-//===----------------------------------------------------------------------===//
-
-namespace  {
-
-class ASTDumper : public ASTNodeTraverser<ASTDumper, TextNodeDumper> {
-
-  TextNodeDumper NodeDumper;
-
-  raw_ostream &OS;
-
-  const bool ShowColors;
-
-public:
-  ASTDumper(raw_ostream &OS, const CommandTraits *Traits,
-            const SourceManager *SM)
-      : ASTDumper(OS, Traits, SM, SM && SM->getDiagnostics().getShowColors()) {}
-
-  ASTDumper(raw_ostream &OS, const CommandTraits *Traits,
-            const SourceManager *SM, bool ShowColors)
-      : ASTDumper(OS, Traits, SM, ShowColors, LangOptions()) {}
-  ASTDumper(raw_ostream &OS, const CommandTraits *Traits,
-            const SourceManager *SM, bool ShowColors,
-            const PrintingPolicy &PrintPolicy)
-      : NodeDumper(OS, ShowColors, SM, PrintPolicy, Traits), OS(OS),
-        ShowColors(ShowColors) {}
-
-  TextNodeDumper &doGetNodeDelegate() { return NodeDumper; }
-
-  void dumpLookups(const DeclContext *DC, bool DumpDecls);
-
-  template <typename SpecializationDecl>
-  void dumpTemplateDeclSpecialization(const SpecializationDecl *D,
-                                      bool DumpExplicitInst, bool DumpRefOnly);
-  template <typename TemplateDecl>
-  void dumpTemplateDecl(const TemplateDecl *D, bool DumpExplicitInst);
-
-  void VisitFunctionTemplateDecl(const FunctionTemplateDecl *D);
-  void VisitClassTemplateDecl(const ClassTemplateDecl *D);
-  void VisitVarTemplateDecl(const VarTemplateDecl *D);
-};
-} // namespace
-
 void ASTDumper::dumpLookups(const DeclContext *DC, bool DumpDecls) {
   NodeDumper.AddChild([=] {
     OS << "StoredDeclsMap ";