diff --git a/lib/Target/X86/X86ISelDAGToDAG.cpp b/lib/Target/X86/X86ISelDAGToDAG.cpp
index 1f53b7cd791..1f5f44cf740 100644
--- a/lib/Target/X86/X86ISelDAGToDAG.cpp
+++ b/lib/Target/X86/X86ISelDAGToDAG.cpp
@@ -192,7 +192,6 @@ namespace {
   private:
     SDNode *Select(SDNode *N) override;
     SDNode *SelectGather(SDNode *N, unsigned Opc);
-    SDNode *SelectAtomic64(SDNode *Node, unsigned Opc);
     SDNode *SelectAtomicLoadArith(SDNode *Node, MVT NVT);
 
     bool FoldOffsetIntoAddress(uint64_t Offset, X86ISelAddressMode &AM);
@@ -1567,24 +1566,6 @@ SDNode *X86DAGToDAGISel::getGlobalBaseReg() {
                              getTargetLowering()->getPointerTy()).getNode();
 }
 
-SDNode *X86DAGToDAGISel::SelectAtomic64(SDNode *Node, unsigned Opc) {
-  SDValue Chain = Node->getOperand(0);
-  SDValue In1 = Node->getOperand(1);
-  SDValue In2L = Node->getOperand(2);
-  SDValue In2H = Node->getOperand(3);
-
-  SDValue Tmp0, Tmp1, Tmp2, Tmp3, Tmp4;
-  if (!SelectAddr(Node, In1, Tmp0, Tmp1, Tmp2, Tmp3, Tmp4))
-    return nullptr;
-  MachineSDNode::mmo_iterator MemOp = MF->allocateMemRefsArray(1);
-  MemOp[0] = cast<MemSDNode>(Node)->getMemOperand();
-  const SDValue Ops[] = { Tmp0, Tmp1, Tmp2, Tmp3, Tmp4, In2L, In2H, Chain};
-  SDNode *ResNode = CurDAG->getMachineNode(Opc, SDLoc(Node),
-                                           MVT::i32, MVT::i32, MVT::Other, Ops);
-  cast<MachineSDNode>(ResNode)->setMemRefs(MemOp, MemOp + 1);
-  return ResNode;
-}
-
 /// Atomic opcode table
 ///
 enum AtomicOpc {