diff --git a/lib/Target/X86/X86InstrSystem.td b/lib/Target/X86/X86InstrSystem.td
index 27f753d3a3b..dced6410de6 100644
--- a/lib/Target/X86/X86InstrSystem.td
+++ b/lib/Target/X86/X86InstrSystem.td
@@ -278,9 +278,9 @@ def PUSHGS32 : I<0xa8, RawFrm, (outs), (ins),
                  "push{l}\t{%gs|gs}", [], IIC_PUSH_SR>, TB, Requires<[Not64BitMode]>;
 
 def PUSHFS64 : I<0xa0, RawFrm, (outs), (ins),
-                 "push{q}\t{%fs|fs}", [], IIC_PUSH_SR>, TB;
+                 "push{q}\t{%fs|fs}", [], IIC_PUSH_SR>, TB, Requires<[In64BitMode]>;
 def PUSHGS64 : I<0xa8, RawFrm, (outs), (ins),
-                 "push{q}\t{%gs|gs}", [], IIC_PUSH_SR>, TB;
+                 "push{q}\t{%gs|gs}", [], IIC_PUSH_SR>, TB, Requires<[In64BitMode]>;
 
 // No "pop cs" instruction.
 def POPSS16 : I<0x17, RawFrm, (outs), (ins),
@@ -309,14 +309,14 @@ def POPFS16 : I<0xa1, RawFrm, (outs), (ins),
 def POPFS32 : I<0xa1, RawFrm, (outs), (ins),
                 "pop{l}\t{%fs|fs}", [], IIC_POP_SR>, TB, Requires<[Not64BitMode]>;
 def POPFS64 : I<0xa1, RawFrm, (outs), (ins),
-                "pop{q}\t{%fs|fs}", [], IIC_POP_SR>, TB;
+                "pop{q}\t{%fs|fs}", [], IIC_POP_SR>, TB, Requires<[In64BitMode]>;
                 
 def POPGS16 : I<0xa9, RawFrm, (outs), (ins),
                 "pop{w}\t{%gs|gs}", [], IIC_POP_SR>, OpSize, TB;
 def POPGS32 : I<0xa9, RawFrm, (outs), (ins),
                 "pop{l}\t{%gs|gs}", [], IIC_POP_SR>, TB, Requires<[Not64BitMode]>;
 def POPGS64 : I<0xa9, RawFrm, (outs), (ins),
-                "pop{q}\t{%gs|gs}", [], IIC_POP_SR>, TB;
+                "pop{q}\t{%gs|gs}", [], IIC_POP_SR>, TB, Requires<[In64BitMode]>;
                  
 
 def LDS16rm : I<0xc5, MRMSrcMem, (outs GR16:$dst), (ins opaque32mem:$src),
diff --git a/utils/TableGen/X86RecognizableInstr.cpp b/utils/TableGen/X86RecognizableInstr.cpp
index 6ae7c3820e4..63a92707336 100644
--- a/utils/TableGen/X86RecognizableInstr.cpp
+++ b/utils/TableGen/X86RecognizableInstr.cpp
@@ -277,10 +277,6 @@ RecognizableInstr::RecognizableInstr(DisassemblerTables &tables,
   }
   // FIXME: These instructions aren't marked as 64-bit in any way
   Is64Bit |= Rec->getName() == "JMP64pcrel32" ||
-             Rec->getName() == "POPFS64" ||
-             Rec->getName() == "POPGS64" ||
-             Rec->getName() == "PUSHFS64" ||
-             Rec->getName() == "PUSHGS64" ||
              Rec->getName() == "REX64_PREFIX" ||
              Rec->getName().find("MOV64") != Name.npos ||
              Rec->getName().find("PUSH64") != Name.npos ||