Transforms/InstCombine/InstCombineShifts.cpp

24   Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
31   if (isa<Constant>(Op0))
37     if (Instruction *Res = FoldShiftByConstant(Op0, CUI, I))
312 Instruction *InstCombiner::FoldShiftByConstant(Value *Op0, ConstantInt *Op1,
320       CanEvaluateShifted(Op0, Op1->getZExtValue(), isLeftShift, *this)) {
322               " to eliminate shift:\n  IN: " << *Op0 << "\n  SH: " << I <<"\n");
325                  GetShiftedValue(Op0, Op1->getZExtValue(), isLeftShift, *this));
331   uint32_t TypeBits = Op0->getType()->getScalarSizeInBits();
338       return ReplaceInstUsesWith(I, Constant::getNullValue(Op0->getType()));
345   if (BinaryOperator *BO = dyn_cast<BinaryOperator>(Op0))
352   if (SelectInst *SI = dyn_cast<SelectInst>(Op0))
355   if (isa<PHINode>(Op0))
360   if (TruncInst *TI = dyn_cast<TruncInst>(Op0)) {
403   if (Op0->hasOneUse()) {
404     if (BinaryOperator *Op0BO = dyn_cast<BinaryOperator>(Op0)) {
524   BinaryOperator *ShiftOp = dyn_cast<BinaryOperator>(Op0);
723   Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
728     if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(Op0)) {
729       unsigned BitWidth = Op0->getType()->getScalarSizeInBits();
738         Constant *RHS = ConstantInt::getSigned(Op0->getType(), isCtPop ? -1:0);
746         MaskedValueIsZero(Op0,APInt::getLowBitsSet(Op1C->getBitWidth(),ShAmt))){
763   Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
771     if (match(Op0, m_Shl(m_Value(X), m_Specific(Op1)))) {
774       if (cast<OverflowingBinaryOperator>(Op0)->hasNoSignedWrap())
792         MaskedValueIsZero(Op0,APInt::getLowBitsSet(Op1C->getBitWidth(),ShAmt))){
799   if (MaskedValueIsZero(Op0,
801     return BinaryOperator::CreateLShr(Op0, Op1);
804   unsigned NumSignBits = ComputeNumSignBits(Op0);
805   if (NumSignBits == Op0->getType()->getScalarSizeInBits())
806     return ReplaceInstUsesWith(I, Op0);