Index: include/llvm/CodeGen/MachineInstr.h
===================================================================
--- include/llvm/CodeGen/MachineInstr.h
+++ include/llvm/CodeGen/MachineInstr.h
@@ -93,6 +93,7 @@
 
   uint8_t NumMemRefs;                   // Information on memory references.
   mmo_iterator MemRefs;
+  bool NonVolatileLdSt;
 
   DebugLoc debugLoc;                    // Source line information.
 
@@ -1179,9 +1180,10 @@
   }
 
   /// Clear this MachineInstr's memory reference descriptor list.
-  void clearMemRefs() {
+  void clearMemRefs(bool IsNonVolatileLdSt) {
     MemRefs = nullptr;
     NumMemRefs = 0;
+    NonVolatileLdSt = IsNonVolatileLdSt;
   }
 
   /// Break any tie involving OpIdx.
Index: lib/CodeGen/BranchFolding.cpp
===================================================================
--- lib/CodeGen/BranchFolding.cpp
+++ lib/CodeGen/BranchFolding.cpp
@@ -793,7 +793,8 @@
 
     if (MBBICommon->mayLoad() || MBBICommon->mayStore())
       if (!hasIdenticalMMOs(&*MBBI, &*MBBICommon))
-        MBBICommon->clearMemRefs();
+        MBBICommon->clearMemRefs(!MBBICommon->hasOrderedMemoryRef() &&
+                                 !MBBI->hasOrderedMemoryRef());
 
     ++MBBI;
     ++MBBICommon;
Index: lib/CodeGen/MachineInstr.cpp
===================================================================
--- lib/CodeGen/MachineInstr.cpp
+++ lib/CodeGen/MachineInstr.cpp
@@ -645,7 +645,7 @@
                            DebugLoc dl, bool NoImp)
     : MCID(&tid), Parent(nullptr), Operands(nullptr), NumOperands(0), Flags(0),
       AsmPrinterFlags(0), NumMemRefs(0), MemRefs(nullptr),
-      debugLoc(std::move(dl)) {
+      NonVolatileLdSt(false), debugLoc(std::move(dl)) {
   assert(debugLoc.hasTrivialDestructor() && "Expected trivial destructor");
 
   // Reserve space for the expected number of operands.
@@ -662,10 +662,9 @@
 /// MachineInstr ctor - Copies MachineInstr arg exactly
 ///
 MachineInstr::MachineInstr(MachineFunction &MF, const MachineInstr &MI)
-  : MCID(&MI.getDesc()), Parent(nullptr), Operands(nullptr), NumOperands(0),
-    Flags(0), AsmPrinterFlags(0),
-    NumMemRefs(MI.NumMemRefs), MemRefs(MI.MemRefs),
-    debugLoc(MI.getDebugLoc()) {
+    : MCID(&MI.getDesc()), Parent(nullptr), Operands(nullptr), NumOperands(0),
+      Flags(0), AsmPrinterFlags(0), NumMemRefs(MI.NumMemRefs),
+      MemRefs(MI.MemRefs), NonVolatileLdSt(false), debugLoc(MI.getDebugLoc()) {
   assert(debugLoc.hasTrivialDestructor() && "Expected trivial destructor");
 
   CapOperands = OperandCapacity::get(MI.getNumOperands());
@@ -1442,7 +1441,7 @@
 
   // Otherwise, if the instruction has no memory reference information,
   // conservatively assume it wasn't preserved.
-  if (memoperands_empty())
+  if (!NonVolatileLdSt && memoperands_empty())
     return true;
 
   // Check the memory reference information for ordered references.