diff --git a/include/llvm/CodeGen/MachineInstr.h b/include/llvm/CodeGen/MachineInstr.h
index 67a06ed774b..3c828116411 100644
--- a/include/llvm/CodeGen/MachineInstr.h
+++ b/include/llvm/CodeGen/MachineInstr.h
@@ -950,7 +950,7 @@ public:
   }
 
   /// isRegTiedToDefOperand - Return true if the use operand of the specified
-  /// index is tied to an def operand. It also returns the def operand index by
+  /// index is tied to a def operand. It also returns the def operand index by
   /// reference if DefOpIdx is not null.
   bool isRegTiedToDefOperand(unsigned UseOpIdx,
                              unsigned *DefOpIdx = nullptr) const {