diff --git a/lib/Target/X86/X86.td b/lib/Target/X86/X86.td
index 0b49d6152e0..784a2642639 100644
--- a/lib/Target/X86/X86.td
+++ b/lib/Target/X86/X86.td
@@ -68,7 +68,7 @@ def Feature3DNowA  : SubtargetFeature<"3dnowa", "X863DNowLevel", "ThreeDNowA",
 def Feature64Bit   : SubtargetFeature<"64bit", "HasX86_64", "true",
                                       "Support 64-bit instructions",
                                       [FeatureCMOV]>;
-def FeatureCMPXCHG16B : SubtargetFeature<"cmpxchg16b", "HasCmpxchg16b", "true",
+def FeatureCMPXCHG16B : SubtargetFeature<"cx16", "HasCmpxchg16b", "true",
                                       "64-bit with cmpxchg16b",
                                       [Feature64Bit]>;
 def FeatureSlowBTMem : SubtargetFeature<"slow-bt-mem", "IsBTMemSlow", "true",