diff --git a/llvm/lib/CodeGen/MachineOutliner.cpp b/llvm/lib/CodeGen/MachineOutliner.cpp
--- a/llvm/lib/CodeGen/MachineOutliner.cpp
+++ b/llvm/lib/CodeGen/MachineOutliner.cpp
@@ -658,19 +658,14 @@
   // Insert the new function into the module.
   MF.insert(MF.begin(), &MBB);
 
-  MachineFunction *OriginalMF = FirstCand.front()->getMF();
-  const std::vector<MCCFIInstruction> &Instrs =
-      OriginalMF->getFrameInstructions();
   for (auto I = FirstCand.front(), E = std::next(FirstCand.back()); I != E;
        ++I) {
     if (I->isDebugInstr())
       continue;
+    // FIXME: Try to emit correct CFI for asynchronous unwind.
+    if (I->isCFIInstruction())
+      continue;
     MachineInstr *NewMI = MF.CloneMachineInstr(&*I);
-    if (I->isCFIInstruction()) {
-      unsigned CFIIndex = NewMI->getOperand(0).getCFIIndex();
-      MCCFIInstruction CFI = Instrs[CFIIndex];
-      (void)MF.addFrameInst(CFI);
-    }
     NewMI->dropMemRefs(MF);
 
     // Don't keep debug information for outlined instructions.
diff --git a/llvm/lib/CodeGen/MachineVerifier.cpp b/llvm/lib/CodeGen/MachineVerifier.cpp
--- a/llvm/lib/CodeGen/MachineVerifier.cpp
+++ b/llvm/lib/CodeGen/MachineVerifier.cpp
@@ -64,6 +64,7 @@
 #include "llvm/InitializePasses.h"
 #include "llvm/MC/LaneBitmask.h"
 #include "llvm/MC/MCAsmInfo.h"
+#include "llvm/MC/MCDwarf.h"
 #include "llvm/MC/MCInstrDesc.h"
 #include "llvm/MC/MCRegisterInfo.h"
 #include "llvm/MC/MCTargetOptions.h"
@@ -2212,6 +2213,11 @@
     }
     break;
 
+  case MachineOperand::MO_CFIIndex:
+    if (MO->getCFIIndex() >= MF->getFrameInstructions().size())
+      report("CFI instruction has invalid index", MO, MONum);
+    break;
+
   default:
     break;
   }
diff --git a/llvm/lib/Target/AArch64/AArch64InstrInfo.cpp b/llvm/lib/Target/AArch64/AArch64InstrInfo.cpp
--- a/llvm/lib/Target/AArch64/AArch64InstrInfo.cpp
+++ b/llvm/lib/Target/AArch64/AArch64InstrInfo.cpp
@@ -7014,12 +7014,10 @@
   // We check to see if CFI Instructions are present, and if they are
   // we find the number of CFI Instructions in the candidates.
   unsigned CFICount = 0;
-  MachineBasicBlock::iterator MBBI = RepeatedSequenceLocs[0].front();
-  for (unsigned Loc = RepeatedSequenceLocs[0].getStartIdx();
-       Loc < RepeatedSequenceLocs[0].getEndIdx() + 1; Loc++) {
-    if (MBBI->isCFIInstruction())
+  for (auto &I : make_range(RepeatedSequenceLocs[0].front(),
+                            std::next(RepeatedSequenceLocs[0].back()))) {
+    if (I.isCFIInstruction())
       CFICount++;
-    MBBI++;
   }
 
   // We compare the number of found CFI Instructions to  the number of CFI
diff --git a/llvm/lib/Target/X86/X86InstrInfo.cpp b/llvm/lib/Target/X86/X86InstrInfo.cpp
--- a/llvm/lib/Target/X86/X86InstrInfo.cpp
+++ b/llvm/lib/Target/X86/X86InstrInfo.cpp
@@ -9488,12 +9488,10 @@
   // We check to see if CFI Instructions are present, and if they are
   // we find the number of CFI Instructions in the candidates.
   unsigned CFICount = 0;
-  MachineBasicBlock::iterator MBBI = RepeatedSequenceLocs[0].front();
-  for (unsigned Loc = RepeatedSequenceLocs[0].getStartIdx();
-       Loc < RepeatedSequenceLocs[0].getEndIdx() + 1; Loc++) {
-    if (MBBI->isCFIInstruction())
+  for (auto &I : make_range(RepeatedSequenceLocs[0].front(),
+                            std::next(RepeatedSequenceLocs[0].back()))) {
+    if (I.isCFIInstruction())
       CFICount++;
-    MBBI++;
   }
 
   // We compare the number of found CFI Instructions to  the number of CFI