diff --git a/lib/CodeGen/MachineInstr.cpp b/lib/CodeGen/MachineInstr.cpp
index a123e36e96b..488516385d7 100644
--- a/lib/CodeGen/MachineInstr.cpp
+++ b/lib/CodeGen/MachineInstr.cpp
@@ -647,11 +647,12 @@ void MachineInstr::addOperand(MachineFunction &MF, const MachineOperand &Op) {
     }
   }
 
+  bool isMetaDataOp = Op.getType() == MachineOperand::MO_Metadata;
   // OpNo now points as the desired insertion point.  Unless this is a variadic
   // instruction, only implicit regs are allowed beyond MCID->getNumOperands().
   // RegMask operands go between the explicit and implicit operands.
   assert((isImpReg || Op.isRegMask() || MCID->isVariadic() ||
-          OpNo < MCID->getNumOperands()) &&
+          OpNo < MCID->getNumOperands() || isMetaDataOp) &&
          "Trying to add an operand to a machine instr that is already done!");
 
   MachineRegisterInfo *MRI = getRegInfo();