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diff --git a/clang-tools-extra/clang-tidy/performance/ForRangeCopyCheck.cpp b/clang-tools-extra/clang-tidy/performance/ForRangeCopyCheck.cpp
new file mode 100644
index 00000000000..88e277720fb
--- /dev/null
+++ b/clang-tools-extra/clang-tidy/performance/ForRangeCopyCheck.cpp
@@ -0,0 +1,177 @@
+//===--- ForRangeCopyCheck.cpp - clang-tidy--------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "ForRangeCopyCheck.h"
+#include "../utils/LexerUtils.h"
+#include "../utils/TypeTraits.h"
+#include "clang/Lex/Lexer.h"
+#include "llvm/ADT/SmallPtrSet.h"
+
+namespace clang {
+namespace tidy {
+namespace performance {
+
+using namespace ::clang::ast_matchers;
+using llvm::SmallPtrSet;
+
+namespace {
+
+template <typename S> bool isSetDifferenceEmpty(const S &S1, const S &S2) {
+  for (const auto &E : S1)
+    if (S2.count(E) == 0)
+      return false;
+  return true;
+}
+
+// Extracts all Nodes keyed by ID from Matches and inserts them into Nodes.
+template <typename Node>
+void extractNodesByIdTo(ArrayRef<BoundNodes> Matches, StringRef ID,
+                        SmallPtrSet<const Node *, 16> &Nodes) {
+  for (const auto &Match : Matches)
+    Nodes.insert(Match.getNodeAs<Node>(ID));
+}
+
+// Finds all DeclRefExprs to VarDecl in Stmt.
+SmallPtrSet<const DeclRefExpr *, 16>
+declRefExprs(const VarDecl &VarDecl, const Stmt &Stmt, ASTContext &Context) {
+  auto Matches = match(
+      findAll(declRefExpr(to(varDecl(equalsNode(&VarDecl)))).bind("declRef")),
+      Stmt, Context);
+  SmallPtrSet<const DeclRefExpr *, 16> DeclRefs;
+  extractNodesByIdTo(Matches, "declRef", DeclRefs);
+  return DeclRefs;
+}
+
+// Finds all DeclRefExprs where a const method is called on VarDecl or VarDecl
+// is the a const reference or value argument to a CallExpr or CXXConstructExpr.
+SmallPtrSet<const DeclRefExpr *, 16>
+constReferenceDeclRefExprs(const VarDecl &VarDecl, const Stmt &Stmt,
+                           ASTContext &Context) {
+  auto DeclRefToVar =
+      declRefExpr(to(varDecl(equalsNode(&VarDecl)))).bind("declRef");
+  auto ConstMethodCallee = callee(cxxMethodDecl(isConst()));
+  // Match method call expressions where the variable is referenced as the this
+  // implicit object argument and opertor call expression for member operators
+  // where the variable is the 0-th argument.
+  auto Matches = match(
+      findAll(expr(anyOf(cxxMemberCallExpr(ConstMethodCallee, on(DeclRefToVar)),
+                         cxxOperatorCallExpr(ConstMethodCallee,
+                                             hasArgument(0, DeclRefToVar))))),
+      Stmt, Context);
+  SmallPtrSet<const DeclRefExpr *, 16> DeclRefs;
+  extractNodesByIdTo(Matches, "declRef", DeclRefs);
+  auto ConstReferenceOrValue =
+      qualType(anyOf(referenceType(pointee(qualType(isConstQualified()))),
+                     unless(anyOf(referenceType(), pointerType()))));
+  auto UsedAsConstRefOrValueArg = forEachArgumentWithParam(
+      DeclRefToVar, parmVarDecl(hasType(ConstReferenceOrValue)));
+  Matches = match(findAll(callExpr(UsedAsConstRefOrValueArg)), Stmt, Context);
+  extractNodesByIdTo(Matches, "declRef", DeclRefs);
+  Matches =
+      match(findAll(cxxConstructExpr(UsedAsConstRefOrValueArg)), Stmt, Context);
+  extractNodesByIdTo(Matches, "declRef", DeclRefs);
+  return DeclRefs;
+}
+
+// Modifies VarDecl to be a reference.
+FixItHint createAmpersandFix(const VarDecl &VarDecl, ASTContext &Context) {
+  SourceLocation AmpLocation = VarDecl.getLocation();
+  auto Token = lexer_utils::getPreviousNonCommentToken(Context, AmpLocation);
+  if (!Token.is(tok::unknown))
+    AmpLocation = Token.getLocation().getLocWithOffset(Token.getLength());
+  return FixItHint::CreateInsertion(AmpLocation, "&");
+}
+
+// Modifies VarDecl to be const.
+FixItHint createConstFix(const VarDecl &VarDecl) {
+  return FixItHint::CreateInsertion(VarDecl.getTypeSpecStartLoc(), "const ");
+}
+
+} // namespace
+
+ForRangeCopyCheck::ForRangeCopyCheck(StringRef Name, ClangTidyContext *Context)
+    : ClangTidyCheck(Name, Context),
+      WarnOnAllAutoCopies(Options.get("WarnOnAllAutoCopies", 0)) {}
+
+void ForRangeCopyCheck::storeOptions(ClangTidyOptions::OptionMap &Opts) {
+  Options.store(Opts, "WarnOnAllAutoCopies", WarnOnAllAutoCopies);
+}
+
+void ForRangeCopyCheck::registerMatchers(MatchFinder *Finder) {
+  // Match loop variables that are not references or pointers or are already
+  // initialized through MaterializeTemporaryExpr which indicates a type
+  // conversion.
+  auto LoopVar = varDecl(
+      hasType(hasCanonicalType(unless(anyOf(referenceType(), pointerType())))),
+      unless(hasInitializer(expr(hasDescendant(materializeTemporaryExpr())))));
+  Finder->addMatcher(cxxForRangeStmt(hasLoopVariable(LoopVar.bind("loopVar")))
+                         .bind("forRange"),
+                     this);
+}
+
+void ForRangeCopyCheck::check(const MatchFinder::MatchResult &Result) {
+  const auto *Var = Result.Nodes.getNodeAs<VarDecl>("loopVar");
+  // Ignore code in macros since we can't place the fixes correctly.
+  if (Var->getLocStart().isMacroID())
+    return;
+  if (handleConstValueCopy(*Var, *Result.Context))
+    return;
+  const auto *ForRange = Result.Nodes.getNodeAs<CXXForRangeStmt>("forRange");
+  handleCopyIsOnlyConstReferenced(*Var, *ForRange, *Result.Context);
+}
+
+bool ForRangeCopyCheck::handleConstValueCopy(const VarDecl &LoopVar,
+                                             ASTContext &Context) {
+  if (WarnOnAllAutoCopies) {
+    // For aggressive check just test that loop variable has auto type.
+    if (!isa<AutoType>(LoopVar.getType()))
+      return false;
+  } else if (!LoopVar.getType().isConstQualified()) {
+    return false;
+  }
+  if (!type_traits::isExpensiveToCopy(LoopVar.getType(), Context))
+    return false;
+  auto Diagnostic =
+      diag(LoopVar.getLocation(),
+           "the loop variable's type is not a reference type; this creates a "
+           "copy in each iteration; consider making this a reference")
+      << createAmpersandFix(LoopVar, Context);
+  if (!LoopVar.getType().isConstQualified())
+    Diagnostic << createConstFix(LoopVar);
+  return true;
+}
+
+bool ForRangeCopyCheck::handleCopyIsOnlyConstReferenced(
+    const VarDecl &LoopVar, const CXXForRangeStmt &ForRange,
+    ASTContext &Context) {
+  if (LoopVar.getType().isConstQualified() ||
+      !type_traits::isExpensiveToCopy(LoopVar.getType(), Context)) {
+    return false;
+  }
+  // Collect all DeclRefExprs to the loop variable and all CallExprs and
+  // CXXConstructExprs where the loop variable is used as argument to a const
+  // reference parameter.
+  // If the difference is empty it is safe for the loop variable to be a const
+  // reference.
+  auto AllDeclRefs = declRefExprs(LoopVar, *ForRange.getBody(), Context);
+  auto ConstReferenceDeclRefs =
+      constReferenceDeclRefExprs(LoopVar, *ForRange.getBody(), Context);
+  if (AllDeclRefs.empty() ||
+      !isSetDifferenceEmpty(AllDeclRefs, ConstReferenceDeclRefs))
+    return false;
+  diag(LoopVar.getLocation(),
+       "loop variable is copied but only used as const reference; consider "
+       "making it a const reference")
+      << createConstFix(LoopVar) << createAmpersandFix(LoopVar, Context);
+  return true;
+}
+
+} // namespace performance
+} // namespace tidy
+} // namespace clang