Transforms/InstCombine/InstCombineShifts.cpp

70 static bool CanEvaluateShifted(Value *V, unsigned NumBits, bool isLeftShift,
86     if (CI->getZExtValue() == NumBits) {
114     return CanEvaluateShifted(I->getOperand(0), NumBits, isLeftShift, IC, I) &&
115            CanEvaluateShifted(I->getOperand(1), NumBits, isLeftShift, IC, I);
126     if (CI->getValue() == NumBits) return true;
132     if (CI->getZExtValue() > NumBits) {
135                        APInt::getLowBitsSet(TypeWidth, NumBits) << LowBits,
151     if (CI->getValue() == NumBits) return true;
157     if (CI->getValue().ult(TypeWidth) && CI->getZExtValue() > NumBits) {
158       unsigned LowBits = CI->getZExtValue() - NumBits;
160                           APInt::getLowBitsSet(TypeWidth, NumBits) << LowBits,
169     return CanEvaluateShifted(SI->getTrueValue(), NumBits, isLeftShift,
171            CanEvaluateShifted(SI->getFalseValue(), NumBits, isLeftShift, IC, SI);
179       if (!CanEvaluateShifted(IncValue, NumBits, isLeftShift,
189 static Value *GetShiftedValue(Value *V, unsigned NumBits, bool isLeftShift,
194       V = IC.Builder->CreateShl(C, NumBits);
196       V = IC.Builder->CreateLShr(C, NumBits);
213         0, GetShiftedValue(I->getOperand(0), NumBits, isLeftShift, IC, DL));
215         1, GetShiftedValue(I->getOperand(1), NumBits, isLeftShift, IC, DL));
228       unsigned NewShAmt = NumBits+CI->getZExtValue();
240     if (CI->getValue() == NumBits) {
241       APInt Mask(APInt::getLowBitsSet(TypeWidth, TypeWidth - NumBits));
253     assert(CI->getZExtValue() > NumBits);
255                                        CI->getZExtValue() - NumBits));
269       unsigned NewShAmt = NumBits+CI->getZExtValue();
280     if (CI->getValue() == NumBits) {
281       APInt Mask(APInt::getHighBitsSet(TypeWidth, TypeWidth - NumBits));
293     assert(CI->getZExtValue() > NumBits);
295                                        CI->getZExtValue() - NumBits));
302         1, GetShiftedValue(I->getOperand(1), NumBits, isLeftShift, IC, DL));
304         2, GetShiftedValue(I->getOperand(2), NumBits, isLeftShift, IC, DL));
312       PN->setIncomingValue(i, GetShiftedValue(PN->getIncomingValue(i), NumBits,