diff --git a/lib/Target/X86/X86CodeEmitter.cpp b/lib/Target/X86/X86CodeEmitter.cpp
index bd9e5c653c7..485eeb56e21 100644
--- a/lib/Target/X86/X86CodeEmitter.cpp
+++ b/lib/Target/X86/X86CodeEmitter.cpp
@@ -603,8 +603,6 @@ void Emitter::emitInstruction(const MachineInstr &MI,
       assert(0 && "JIT does not support inline asm!\n");
     case TargetInstrInfo::LABEL:
       assert(0 && "JIT does not support meta labels!\n");
-    case X86::IMPLICIT_USE:
-    case X86::IMPLICIT_DEF:
     case X86::IMPLICIT_DEF_GR8:
     case X86::IMPLICIT_DEF_GR16:
     case X86::IMPLICIT_DEF_GR32:
diff --git a/lib/Target/X86/X86InstrInfo.td b/lib/Target/X86/X86InstrInfo.td
index b9426c71125..1807c0d1bd0 100644
--- a/lib/Target/X86/X86InstrInfo.td
+++ b/lib/Target/X86/X86InstrInfo.td
@@ -263,12 +263,7 @@ def ADJCALLSTACKUP   : I<0, Pseudo, (outs), (ins i32imm:$amt1, i32imm:$amt2),
                          "#ADJCALLSTACKUP",
                          [(X86callseq_end imm:$amt1, imm:$amt2)]>;
 }
-def IMPLICIT_USE     : I<0, Pseudo, (outs), (ins variable_ops),
-                         "#IMPLICIT_USE", []>;
 let isImplicitDef = 1 in {
-let neverHasSideEffects = 1 in
-def IMPLICIT_DEF     : I<0, Pseudo, (outs variable_ops), (ins),
-                          "#IMPLICIT_DEF", []>;
 def IMPLICIT_DEF_GR8  : I<0, Pseudo, (outs GR8:$dst), (ins),
                          "#IMPLICIT_DEF $dst",
                          [(set GR8:$dst, (undef))]>;