Index: llvm/lib/Target/Hexagon/BitTracker.cpp
===================================================================
--- llvm/lib/Target/Hexagon/BitTracker.cpp
+++ llvm/lib/Target/Hexagon/BitTracker.cpp
@@ -860,7 +860,7 @@
              << " cell: " << ME.getCell(RU, Map) << "\n";
     }
     dbgs() << "Outputs:\n";
-    for (const std::pair<unsigned, RegisterCell> &P : ResMap) {
+    for (const std::pair<const unsigned, RegisterCell> &P : ResMap) {
       RegisterRef RD(P.first);
       dbgs() << "  " << printReg(P.first, &ME.TRI) << " cell: "
              << ME.getCell(RD, ResMap) << "\n";
Index: llvm/lib/Target/Hexagon/HexagonConstExtenders.cpp
===================================================================
--- llvm/lib/Target/Hexagon/HexagonConstExtenders.cpp
+++ llvm/lib/Target/Hexagon/HexagonConstExtenders.cpp
@@ -555,7 +555,7 @@
   LLVM_ATTRIBUTE_UNUSED
   raw_ostream &operator<< (raw_ostream &OS, const PrintIMap &P) {
     OS << "{\n";
-    for (const std::pair<HCE::ExtenderInit,HCE::IndexList> &Q : P.IMap) {
+    for (const std::pair<const HCE::ExtenderInit, HCE::IndexList> &Q : P.IMap) {
       OS << "  " << PrintInit(Q.first, P.HRI) << " -> {";
       for (unsigned I : Q.second)
         OS << ' ' << I;
@@ -1895,7 +1895,7 @@
   LocDefList Defs;
   bool Changed = false;
 
-  for (const std::pair<ExtenderInit,IndexList> &P : IMap) {
+  for (const std::pair<const ExtenderInit, IndexList> &P : IMap) {
     const IndexList &Idxs = P.second;
     if (Idxs.size() < CountThreshold)
       continue;
Index: llvm/lib/Target/Hexagon/HexagonLoopIdiomRecognition.cpp
===================================================================
--- llvm/lib/Target/Hexagon/HexagonLoopIdiomRecognition.cpp
+++ llvm/lib/Target/Hexagon/HexagonLoopIdiomRecognition.cpp
@@ -2335,7 +2335,7 @@
         continue;
       if (!Worklist.count(&In) && In.mayHaveSideEffects())
         return false;
-      for (const auto &K : In.users()) {
+      for (const auto K : In.users()) {
         Instruction *UseI = dyn_cast<Instruction>(K);
         if (!UseI)
           continue;
Index: llvm/lib/Target/Hexagon/HexagonVLIWPacketizer.cpp
===================================================================
--- llvm/lib/Target/Hexagon/HexagonVLIWPacketizer.cpp
+++ llvm/lib/Target/Hexagon/HexagonVLIWPacketizer.cpp
@@ -309,7 +309,7 @@
   //   r0 = ...
   //   J2_jumpr r0
   if (DepType == SDep::Data) {
-    for (const MachineOperand MO : MI.operands())
+    for (const MachineOperand &MO : MI.operands())
       if (MO.isReg() && MO.getReg() == DepReg && !MO.isImplicit())
         return true;
   }
Index: llvm/lib/Target/Hexagon/RDFLiveness.cpp
===================================================================
--- llvm/lib/Target/Hexagon/RDFLiveness.cpp
+++ llvm/lib/Target/Hexagon/RDFLiveness.cpp
@@ -620,7 +620,7 @@
     for (NodeAddr<UseNode*> UA : PUs) {
       std::map<NodeId,RegisterAggr> &PUM = PhiUp[UA.Id];
       RegisterRef UR = PRI.normalize(UA.Addr->getRegRef(DFG));
-      for (const std::pair<NodeId,RegisterAggr> &P : PUM) {
+      for (const std::pair<const NodeId, RegisterAggr> &P : PUM) {
         bool Changed = false;
         const RegisterAggr &MidDefs = P.second;
 
@@ -636,7 +636,7 @@
         //     if MidDefs does not cover (R,U)
         //       then add (R-MidDefs,U) to RealUseMap[P]
         //
-        for (const std::pair<RegisterId,NodeRefSet> &T : RUM) {
+        for (const std::pair<const RegisterId, NodeRefSet> &T : RUM) {
           RegisterRef R(T.first);
           // The current phi (PA) could be a phi for a regmask. It could
           // reach a whole variety of uses that are not related to the
@@ -768,7 +768,7 @@
         auto PrA = DFG.addr<BlockNode*>(PUA.Addr->getPredecessor());
         RefMap &LOX = PhiLOX[PrA.Addr->getCode()];
 
-        for (const std::pair<RegisterId,NodeRefSet> &RS : RUs) {
+        for (const std::pair<const RegisterId, NodeRefSet> &RS : RUs) {
           // We need to visit each individual use.
           for (std::pair<NodeId,LaneBitmask> P : RS.second) {
             // Create a register ref corresponding to the use, and find
@@ -991,7 +991,7 @@
   RefMap LiveInCopy = LiveIn;
   LiveIn.clear();
 
-  for (const std::pair<RegisterId,NodeRefSet> &LE : LiveInCopy) {
+  for (const std::pair<const RegisterId, NodeRefSet> &LE : LiveInCopy) {
     RegisterRef LRef(LE.first);
     NodeRefSet &NewDefs = LiveIn[LRef.Reg]; // To be filled.
     const NodeRefSet &OldDefs = LE.second;
@@ -1105,7 +1105,7 @@
 
   for (auto C : IIDF[B]) {
     RegisterAggr &LiveC = LiveMap[C];
-    for (const std::pair<RegisterId,NodeRefSet> &S : LiveIn)
+    for (const std::pair<const RegisterId, NodeRefSet> &S : LiveIn)
       for (auto R : S.second)
         if (MDT.properlyDominates(getBlockWithRef(R.first), C))
           LiveC.insert(RegisterRef(S.first, R.second));