Add safety check that didn't show up in testing.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@128467 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/ARM/ARMLoadStoreOptimizer.cpp b/lib/Target/ARM/ARMLoadStoreOptimizer.cpp
index af73116..0dab835 100644
--- a/lib/Target/ARM/ARMLoadStoreOptimizer.cpp
+++ b/lib/Target/ARM/ARMLoadStoreOptimizer.cpp
@@ -350,6 +350,7 @@
   bool isDef = (isi32Load(Opcode) || Opcode == ARM::VLDRS ||
                 Opcode == ARM::VLDRD);
   Opcode = getLoadStoreMultipleOpcode(Opcode, Mode);
+  if (!Opcode) return false;
   MachineInstrBuilder MIB = BuildMI(MBB, MBBI, dl, TII->get(Opcode))
     .addReg(Base, getKillRegState(BaseKill))
     .addImm(Pred).addReg(PredReg);