Add an assert to check for empty flags for MachineMemOperand.

llvm-svn: 53680
diff --git a/llvm/lib/CodeGen/MachineInstr.cpp b/llvm/lib/CodeGen/MachineInstr.cpp
index 36212ba..595a914 100644
--- a/llvm/lib/CodeGen/MachineInstr.cpp
+++ b/llvm/lib/CodeGen/MachineInstr.cpp
@@ -246,6 +246,7 @@
   : Offset(o), Size(s), V(v),
     Flags((f & 7) | ((Log2_32(a) + 1) << 3)) {
   assert(isPowerOf2_32(a) && "Alignment is not a power of 2!");
+  assert((isLoad() || isStore()) && "Not a load/store!");
 }
 
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