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diff --git a/lib/Index/SimpleFormatContext.h b/lib/Index/SimpleFormatContext.h
new file mode 100644
index 0000000000000..fde43aed211f1
--- /dev/null
+++ b/lib/Index/SimpleFormatContext.h
@@ -0,0 +1,77 @@
+//===--- SimpleFormatContext.h ----------------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+/// \file
+///
+/// \brief Defines a utility class for use of clang-format in libclang
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_SIMPLE_FORM_CONTEXT_H
+#define LLVM_CLANG_SIMPLE_FORM_CONTEXT_H
+
+#include "clang/Basic/Diagnostic.h"
+#include "clang/Basic/DiagnosticOptions.h"
+#include "clang/Basic/FileManager.h"
+#include "clang/Basic/LangOptions.h"
+#include "clang/Basic/SourceManager.h"
+#include "clang/Rewrite/Core/Rewriter.h"
+#include "llvm/Support/FileSystem.h"
+#include "llvm/Support/Path.h"
+#include "llvm/Support/raw_ostream.h"
+
+namespace clang {
+namespace index {
+
+/// \brief A small class to be used by libclang clients to format
+/// a declaration string in memory. This object is instantiated once
+/// and used each time a formatting is needed.
+class SimpleFormatContext {
+public:
+  SimpleFormatContext(LangOptions Options)
+      : DiagOpts(new DiagnosticOptions()),
+        Diagnostics(new DiagnosticsEngine(new DiagnosticIDs,
+                                          DiagOpts.getPtr())),
+        Files((FileSystemOptions())),
+        Sources(*Diagnostics, Files),
+        Rewrite(Sources, Options) {
+    Diagnostics->setClient(new IgnoringDiagConsumer, true);
+  }
+
+  ~SimpleFormatContext() { }
+
+  FileID createInMemoryFile(StringRef Name, StringRef Content) {
+    const llvm::MemoryBuffer *Source =
+        llvm::MemoryBuffer::getMemBuffer(Content);
+    const FileEntry *Entry =
+        Files.getVirtualFile(Name, Source->getBufferSize(), 0);
+    Sources.overrideFileContents(Entry, Source, true);
+    assert(Entry != NULL);
+    return Sources.createFileID(Entry, SourceLocation(), SrcMgr::C_User);
+  }
+
+  std::string getRewrittenText(FileID ID) {
+    std::string Result;
+    llvm::raw_string_ostream OS(Result);
+    Rewrite.getEditBuffer(ID).write(OS);
+    OS.flush();
+    return Result;
+  }
+
+  IntrusiveRefCntPtr<DiagnosticOptions> DiagOpts;
+  IntrusiveRefCntPtr<DiagnosticsEngine> Diagnostics;
+  FileManager Files;
+  SourceManager Sources;
+  Rewriter Rewrite;
+};
+
+} // end namespace index
+} // end namespace clang
+
+#endif