/// are set if the result needs to be inserted and/or extracted from vectors.
unsigned getScalarizationOverhead(Type *Ty, bool Insert, bool Extract) const;
- const TargetLoweringBase *getTLI() const { return TM->getTargetLowering(); }
+ /// Estimate the cost overhead of SK_Alternate shuffle.
+ unsigned getAltShuffleOverhead(Type *Ty) const;
+
+ const TargetLoweringBase *getTLI() const {
+ return TM->getSubtargetImpl()->getTargetLowering();
+ }
public:
BasicTTI() : ImmutablePass(ID), TM(nullptr) {
return OpCost;
}
+unsigned BasicTTI::getAltShuffleOverhead(Type *Ty) const {
+ assert(Ty->isVectorTy() && "Can only shuffle vectors");
+ unsigned Cost = 0;
+ // Shuffle cost is equal to the cost of extracting element from its argument
+ // plus the cost of inserting them onto the result vector.
+
+ // e.g. <4 x float> has a mask of <0,5,2,7> i.e we need to extract from index
+ // 0 of first vector, index 1 of second vector,index 2 of first vector and
+ // finally index 3 of second vector and insert them at index <0,1,2,3> of
+ // result vector.
+ for (int i = 0, e = Ty->getVectorNumElements(); i < e; ++i) {
+ Cost += TopTTI->getVectorInstrCost(Instruction::InsertElement, Ty, i);
+ Cost += TopTTI->getVectorInstrCost(Instruction::ExtractElement, Ty, i);
+ }
+ return Cost;
+}
+
unsigned BasicTTI::getShuffleCost(ShuffleKind Kind, Type *Tp, int Index,
Type *SubTp) const {
+ if (Kind == SK_Alternate) {
+ return getAltShuffleOverhead(Tp);
+ }
return 1;
}
case Intrinsic::pow: ISD = ISD::FPOW; break;
case Intrinsic::fma: ISD = ISD::FMA; break;
case Intrinsic::fmuladd: ISD = ISD::FMA; break;
+ // FIXME: We should return 0 whenever getIntrinsicCost == TCC_Free.
case Intrinsic::lifetime_start:
case Intrinsic::lifetime_end:
return 0;