diff --git a/lib/Target/Mips/MCTargetDesc/MipsBaseInfo.h b/lib/Target/Mips/MCTargetDesc/MipsBaseInfo.h
index f7aedd02068..234455e0c7f 100644
--- a/lib/Target/Mips/MCTargetDesc/MipsBaseInfo.h
+++ b/lib/Target/Mips/MCTargetDesc/MipsBaseInfo.h
@@ -81,6 +81,8 @@ namespace MipsII {
     MO_GOT_PAGE,
     MO_GOT_OFST,
 
+    /// MO_HIGHER/HIGHEST - Represents the highest or higher half word of a
+    /// 64-bit symbol address.
     MO_HIGHER,
     MO_HIGHEST
   };