remove the isDesirableToCommuteWithShift of X86

Author: LiqinWeng

llvm/lib/Target/X86/X86ISelLowering.cpp

@@ -60673,20 +60673,3 @@ Align X86TargetLowering::getPrefLoopAlignment(MachineLoop *ML) const {
     return Align(1ULL << ExperimentalPrefInnermostLoopAlignment);
   return TargetLowering::getPrefLoopAlignment();
 }
-
-bool X86TargetLowering::isDesirableToCommuteWithShift(
-    const SDNode *N, CombineLevel Level) const {
-  assert((N->getOpcode() == ISD::SHL || N->getOpcode() == ISD::SRA ||
-          N->getOpcode() == ISD::SRL) &&
-         "Expected shift op");
-
-  SDValue ShiftLHS = N->getOperand(0);
-  if (!ShiftLHS->hasOneUse())
-    return false;
-
-  if (ShiftLHS.getOpcode() == ISD::SIGN_EXTEND &&
-      !ShiftLHS.getOperand(0)->hasOneUse())
-    return false;
-
-  return true;
-}

llvm/lib/Target/X86/X86ISelLowering.h

@@ -1901,9 +1901,6 @@ namespace llvm {
 
     SDValue getMOVL(SelectionDAG &DAG, const SDLoc &dl, MVT VT, SDValue V1,
                     SDValue V2) const;
-
-    bool isDesirableToCommuteWithShift(const SDNode *N,
-                                       CombineLevel Level) const override;
   };
 
   namespace X86 {