Index: llvm/lib/Transforms/IPO/WholeProgramDevirt.cpp
===================================================================
--- llvm/lib/Transforms/IPO/WholeProgramDevirt.cpp
+++ llvm/lib/Transforms/IPO/WholeProgramDevirt.cpp
@@ -842,7 +842,7 @@
 bool DevirtIndex::tryFindVirtualCallTargets(
     std::vector<ValueInfo> &TargetsForSlot, const TypeIdCompatibleVtableInfo TIdInfo,
     uint64_t ByteOffset) {
-  for (const TypeIdOffsetVtableInfo P : TIdInfo) {
+  for (const TypeIdOffsetVtableInfo &P : TIdInfo) {
     // Ensure that we have at most one external linkage vtable initializer.
     assert(P.VTableVI.getSummaryList().size() == 1 ||
            llvm::count_if(
Index: llvm/lib/Transforms/Scalar/LoopLoadElimination.cpp
===================================================================
--- llvm/lib/Transforms/Scalar/LoopLoadElimination.cpp
+++ llvm/lib/Transforms/Scalar/LoopLoadElimination.cpp
@@ -489,7 +489,7 @@
     // Filter the candidates further.
     SmallVector<StoreToLoadForwardingCandidate, 4> Candidates;
     unsigned NumForwarding = 0;
-    for (const StoreToLoadForwardingCandidate Cand : StoreToLoadDependences) {
+    for (const StoreToLoadForwardingCandidate &Cand : StoreToLoadDependences) {
       LLVM_DEBUG(dbgs() << "Candidate " << Cand);
 
       // Make sure that the stored values is available everywhere in the loop in
Index: llvm/lib/Transforms/Scalar/SCCP.cpp
===================================================================
--- llvm/lib/Transforms/Scalar/SCCP.cpp
+++ llvm/lib/Transforms/Scalar/SCCP.cpp
@@ -2197,7 +2197,7 @@
     findReturnsToZap(*F, ReturnsToZap, Solver);
   }
 
-  for (const auto &F : Solver.getMRVFunctionsTracked()) {
+  for (const auto F : Solver.getMRVFunctionsTracked()) {
     assert(F->getReturnType()->isStructTy() &&
            "The return type should be a struct");
     StructType *STy = cast<StructType>(F->getReturnType());
Index: llvm/lib/Transforms/Utils/InlineFunction.cpp
===================================================================
--- llvm/lib/Transforms/Utils/InlineFunction.cpp
+++ llvm/lib/Transforms/Utils/InlineFunction.cpp
@@ -1473,7 +1473,7 @@
                             BlockFrequencyInfo *CalleeBFI,
                             const BasicBlock &CalleeEntryBlock) {
   SmallPtrSet<BasicBlock *, 16> ClonedBBs;
-  for (auto const &Entry : VMap) {
+  for (auto const Entry : VMap) {
     if (!isa<BasicBlock>(Entry.first) || !Entry.second)
       continue;
     auto *OrigBB = cast<BasicBlock>(Entry.first);
@@ -1531,7 +1531,7 @@
   // During inlining ?
   if (VMap) {
     uint64_t cloneEntryCount = priorEntryCount - newEntryCount;
-    for (auto const &Entry : *VMap)
+    for (auto const Entry : *VMap)
       if (isa<CallInst>(Entry.first))
         if (auto *CI = dyn_cast_or_null<CallInst>(Entry.second))
           CI->updateProfWeight(cloneEntryCount, priorEntryCount);
Index: llvm/lib/Transforms/Utils/LoopUnrollPeel.cpp
===================================================================
--- llvm/lib/Transforms/Utils/LoopUnrollPeel.cpp
+++ llvm/lib/Transforms/Utils/LoopUnrollPeel.cpp
@@ -584,7 +584,7 @@
 
   // LastValueMap is updated with the values for the current loop
   // which are used the next time this function is called.
-  for (const auto &KV : VMap)
+  for (const auto KV : VMap)
     LVMap[KV.first] = KV.second;
 }