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diff --git a/include/clang/Analysis/Analyses/ExprMutationAnalyzer.h b/include/clang/Analysis/Analyses/ExprMutationAnalyzer.h
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index 0000000000000..edc6e00f1d008
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+++ b/include/clang/Analysis/Analyses/ExprMutationAnalyzer.h
@@ -0,0 +1,96 @@
+//===---------- ExprMutationAnalyzer.h ------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+#ifndef LLVM_CLANG_ANALYSIS_ANALYSES_EXPRMUTATIONANALYZER_H
+#define LLVM_CLANG_ANALYSIS_ANALYSES_EXPRMUTATIONANALYZER_H
+
+#include <type_traits>
+
+#include "clang/AST/AST.h"
+#include "clang/ASTMatchers/ASTMatchers.h"
+#include "llvm/ADT/DenseMap.h"
+
+namespace clang {
+
+class FunctionParmMutationAnalyzer;
+
+/// 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 Expr *Exp) { return findMutation(Exp) != nullptr; }
+  bool isMutated(const Decl *Dec) { return findMutation(Dec) != nullptr; }
+  const Stmt *findMutation(const Expr *Exp);
+  const Stmt *findMutation(const Decl *Dec);
+
+  bool isPointeeMutated(const Expr *Exp) {
+    return findPointeeMutation(Exp) != nullptr;
+  }
+  bool isPointeeMutated(const Decl *Dec) {
+    return findPointeeMutation(Dec) != nullptr;
+  }
+  const Stmt *findPointeeMutation(const Expr *Exp);
+  const Stmt *findPointeeMutation(const Decl *Dec);
+
+private:
+  using MutationFinder = const Stmt *(ExprMutationAnalyzer::*)(const Expr *);
+  using ResultMap = llvm::DenseMap<const Expr *, const Stmt *>;
+
+  const Stmt *findMutationMemoized(const Expr *Exp,
+                                   llvm::ArrayRef<MutationFinder> Finders,
+                                   ResultMap &MemoizedResults);
+  const Stmt *tryEachDeclRef(const Decl *Dec, MutationFinder Finder);
+
+  bool isUnevaluated(const Expr *Exp);
+
+  const Stmt *findExprMutation(ArrayRef<ast_matchers::BoundNodes> Matches);
+  const Stmt *findDeclMutation(ArrayRef<ast_matchers::BoundNodes> Matches);
+  const Stmt *
+  findExprPointeeMutation(ArrayRef<ast_matchers::BoundNodes> Matches);
+  const Stmt *
+  findDeclPointeeMutation(ArrayRef<ast_matchers::BoundNodes> Matches);
+
+  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 *findFunctionArgMutation(const Expr *Exp);
+
+  const Stmt &Stm;
+  ASTContext &Context;
+  llvm::DenseMap<const FunctionDecl *,
+                 std::unique_ptr<FunctionParmMutationAnalyzer>>
+      FuncParmAnalyzer;
+  ResultMap Results;
+  ResultMap PointeeResults;
+};
+
+// A convenient wrapper around ExprMutationAnalyzer for analyzing function
+// params.
+class FunctionParmMutationAnalyzer {
+public:
+  FunctionParmMutationAnalyzer(const FunctionDecl &Func, ASTContext &Context);
+
+  bool isMutated(const ParmVarDecl *Parm) {
+    return findMutation(Parm) != nullptr;
+  }
+  const Stmt *findMutation(const ParmVarDecl *Parm);
+
+private:
+  ExprMutationAnalyzer BodyAnalyzer;
+  llvm::DenseMap<const ParmVarDecl *, const Stmt *> Results;
+};
+
+} // namespace clang
+
+#endif // LLVM_CLANG_ANALYSIS_ANALYSES_EXPRMUTATIONANALYZER_H