diff --git a/lib/Target/X86/AsmParser/X86AsmParser.cpp b/lib/Target/X86/AsmParser/X86AsmParser.cpp
index bc2ff332bbd..20907b494a4 100644
--- a/lib/Target/X86/AsmParser/X86AsmParser.cpp
+++ b/lib/Target/X86/AsmParser/X86AsmParser.cpp
@@ -908,10 +908,16 @@ bool X86AsmParser::ParseRegister(unsigned &RegNo,
     if (RegNo == X86::RIZ ||
         X86MCRegisterClasses[X86::GR64RegClassID].contains(RegNo) ||
         X86II::isX86_64NonExtLowByteReg(RegNo) ||
-        X86II::isX86_64ExtendedReg(RegNo))
+        X86II::isX86_64ExtendedReg(RegNo) ||
+        X86II::is32ExtendedReg(RegNo))
       return Error(StartLoc, "register %"
                    + Tok.getString() + " is only available in 64-bit mode",
                    SMRange(StartLoc, EndLoc));
+  } else if (!getSTI().getFeatureBits()[X86::FeatureAVX512]) {
+    if (X86II::is32ExtendedReg(RegNo))
+      return Error(StartLoc, "register %"
+                   + Tok.getString() + " is only available in with AVX512",
+                   SMRange(StartLoc, EndLoc));
   }
 
   // Parse "%st" as "%st(0)" and "%st(1)", which is multiple tokens.