Index: lib/CodeGen/SelectionDAG/SelectionDAGDumper.cpp
===================================================================
--- lib/CodeGen/SelectionDAG/SelectionDAGDumper.cpp
+++ lib/CodeGen/SelectionDAG/SelectionDAGDumper.cpp
@@ -426,14 +426,27 @@
 // Print the MMO with more information from the SelectionDAG.
 static void printMemOperand(raw_ostream &OS, const MachineMemOperand &MMO,
                             const SelectionDAG *G) {
-  const MachineFunction &MF = G->getMachineFunction();
-  const Function &F = MF.getFunction();
-  const MachineFrameInfo &MFI = MF.getFrameInfo();
-  const TargetInstrInfo *TII = G->getSubtarget().getInstrInfo();
-  ModuleSlotTracker MST(F.getParent());
-  MST.incorporateFunction(F);
+  const Module *M = nullptr;
+  const MachineFunction *MF = nullptr;
+  const MachineFrameInfo *MFI = nullptr;
+  const TargetInstrInfo *TII = nullptr;
+  LLVMContext *Ctx = nullptr;
+  std::unique_ptr<LLVMContext> CtxPtr;
+  if (G) {
+    MF = &G->getMachineFunction();
+    M = MF->getFunction().getParent();
+    MFI = &MF->getFrameInfo();
+    TII = G->getSubtarget().getInstrInfo();
+    Ctx = G->getContext();
+  } else {
+    CtxPtr = llvm::make_unique<LLVMContext>();
+    Ctx = CtxPtr.get();
+  }
+  ModuleSlotTracker MST(M);
+  if (MF)
+    MST.incorporateFunction(MF->getFunction());
   SmallVector<StringRef, 0> SSNs;
-  MMO.print(OS, MST, SSNs, *G->getContext(), &MFI, TII);
+  MMO.print(OS, MST, SSNs, *Ctx, MFI, TII);
 }
 
 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)