diff --git a/llvm/lib/Target/X86/MCTargetDesc/X86InstComments.cpp b/llvm/lib/Target/X86/MCTargetDesc/X86InstComments.cpp
--- a/llvm/lib/Target/X86/MCTargetDesc/X86InstComments.cpp
+++ b/llvm/lib/Target/X86/MCTargetDesc/X86InstComments.cpp
@@ -278,7 +278,7 @@
 
   // MASKZ: zmmX {%kY} {z}
   if (MaskWithZero)
-    OS << " {z}";
+    OS << "{z}";
 }
 
 static bool printFMAComments(const MCInst *MI, raw_ostream &OS,
diff --git a/llvm/lib/Target/X86/X86MCInstLower.cpp b/llvm/lib/Target/X86/X86MCInstLower.cpp
--- a/llvm/lib/Target/X86/X86MCInstLower.cpp
+++ b/llvm/lib/Target/X86/X86MCInstLower.cpp
@@ -1877,7 +1877,7 @@
       CS << " {%" << GetRegisterName(WriteMaskOp.getReg()) << "}";
 
       if (SrcOp1Idx == 2) {
-        CS << " {z}";
+        CS << "{z}";
       }
     }
   }