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diff --git a/include/clang/AST/DataCollection.h b/include/clang/AST/DataCollection.h
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+//===--- DatatCollection.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 This file declares helper methods for collecting data from AST nodes.
+///
+/// To collect data from Stmt nodes, subclass ConstStmtVisitor and include
+/// StmtDataCollectors.inc after defining the macros that you need. This
+/// provides data collection implementations for most Stmt kinds. Note
+/// that that code requires some conditions to be met:
+///
+///   - There must be a method addData(const T &Data) that accepts strings,
+///     integral types as well as QualType. All data is forwarded using
+///     to this method.
+///   - The ASTContext of the Stmt must be accessible by the name Context.
+///
+/// It is also possible to override individual visit methods. Have a look at
+/// the DataCollector in lib/Analysis/CloneDetection.cpp for a usage example.
+///
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_AST_DATACOLLECTION_H
+#define LLVM_CLANG_AST_DATACOLLECTION_H
+
+#include "clang/AST/ASTContext.h"
+
+namespace clang {
+namespace data_collection {
+
+/// Returns a string that represents all macro expansions that expanded into the
+/// given SourceLocation.
+///
+/// If 'getMacroStack(A) == getMacroStack(B)' is true, then the SourceLocations
+/// A and B are expanded from the same macros in the same order.
+std::string getMacroStack(SourceLocation Loc, ASTContext &Context);
+
+/// Utility functions for implementing addData() for a consumer that has a
+/// method update(StringRef)
+template <class T>
+void addDataToConsumer(T &DataConsumer, llvm::StringRef Str) {
+  DataConsumer.update(Str);
+}
+
+template <class T> void addDataToConsumer(T &DataConsumer, const QualType &QT) {
+  addDataToConsumer(DataConsumer, QT.getAsString());
+}
+
+template <class T, class Type>
+typename std::enable_if<
+    std::is_integral<Type>::value || std::is_enum<Type>::value ||
+    std::is_convertible<Type, size_t>::value // for llvm::hash_code
+    >::type
+addDataToConsumer(T &DataConsumer, Type Data) {
+  DataConsumer.update(StringRef(reinterpret_cast<char *>(&Data), sizeof(Data)));
+}
+
+} // end namespace data_collection
+} // end namespace clang
+
+#endif // LLVM_CLANG_AST_DATACOLLECTION_H