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diff --git a/clang-tools-extra/clang-tidy/utils/ExprMutationAnalyzer.h b/clang-tools-extra/clang-tidy/utils/ExprMutationAnalyzer.h
new file mode 100644
index 00000000000..256bb712891
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+++ b/clang-tools-extra/clang-tidy/utils/ExprMutationAnalyzer.h
@@ -0,0 +1,56 @@
+//===---------- ExprMutationAnalyzer.h - clang-tidy -----------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+#ifndef LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_EXPRMUTATIONANALYZER_H
+#define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_EXPRMUTATIONANALYZER_H
+
+#include <type_traits>
+
+#include "clang/AST/AST.h"
+#include "clang/ASTMatchers/ASTMatchers.h"
+#include "llvm/ADT/DenseMap.h"
+
+namespace clang {
+namespace tidy {
+namespace utils {
+
+/// Analyzes whether any mutative operations are applied to an expression within
+/// a given statement.
+class ExprMutationAnalyzer {
+public:
+  ExprMutationAnalyzer(const Stmt *Stm, ASTContext *Context)
+      : Stm(Stm), Context(Context) {}
+
+  bool isMutated(const Decl *Dec) { return findDeclMutation(Dec) != nullptr; }
+  bool isMutated(const Expr *Exp) { return findMutation(Exp) != nullptr; }
+  const Stmt *findMutation(const Expr *Exp);
+
+private:
+  bool isUnevaluated(const Expr *Exp);
+
+  const Stmt *findExprMutation(ArrayRef<ast_matchers::BoundNodes> Matches);
+  const Stmt *findDeclMutation(ArrayRef<ast_matchers::BoundNodes> Matches);
+  const Stmt *findDeclMutation(const Decl *Dec);
+
+  const Stmt *findDirectMutation(const Expr *Exp);
+  const Stmt *findMemberMutation(const Expr *Exp);
+  const Stmt *findArrayElementMutation(const Expr *Exp);
+  const Stmt *findCastMutation(const Expr *Exp);
+  const Stmt *findRangeLoopMutation(const Expr *Exp);
+  const Stmt *findReferenceMutation(const Expr *Exp);
+
+  const Stmt *const Stm;
+  ASTContext *const Context;
+  llvm::DenseMap<const Expr *, const Stmt *> Results;
+};
+
+} // namespace utils
+} // namespace tidy
+} // namespace clang
+
+#endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_EXPRMUTATIONANALYZER_H