Unverified Commit aacaf3d5 authored by Florian Hahn's avatar Florian Hahn
Browse files

[VPlan] Simplify VPDerivedIV truncation handling (NFCI). 

Address post-commit simplification suggestion for 8a56179b: Replace
IsTruncated by conditionally setting TruncResultTy only if truncation
is required.
parent 16888689

llvm/lib/Transforms/Vectorize/LoopVectorize.cpp

+4 −3
Original line number Diff line number Diff line
@@ -9488,10 +9488,11 @@ void VPDerivedIVRecipe::execute(VPTransformState &State) { 
                                          getStartValue()->getLiveInIRValue(),

                                          Step, Kind, BinOp);

  DerivedIV->setName("offset.idx");

  if (ResultTy != DerivedIV->getType()) {

    assert(IsTruncated && Step->getType()->isIntegerTy() &&

  if (TruncResultTy) {

    assert(TruncResultTy != DerivedIV->getType() &&

           Step->getType()->isIntegerTy() &&

           "Truncation requires an integer step");

    DerivedIV = State.Builder.CreateTrunc(DerivedIV, ResultTy);

    DerivedIV = State.Builder.CreateTrunc(DerivedIV, TruncResultTy);

  }

  assert(DerivedIV != CanonicalIV && "IV didn't need transforming?");

llvm/lib/Transforms/Vectorize/VPlan.h

+7 −10
Original line number Diff line number Diff line
@@ -2139,24 +2139,21 @@ public: 
/// an IV with different start and step values, using Start + CanonicalIV *

/// Step.

class VPDerivedIVRecipe : public VPRecipeBase, public VPValue {

  /// The type of the result value. It may be smaller than the type of the

  /// induction and in this case it will get truncated to ResultTy.

  Type *ResultTy;



  bool IsTruncated;

  /// If not nullptr, the result of the induction will get truncated to

  /// TruncResultTy.

  Type *TruncResultTy;



  /// Induction descriptor for the induction the canonical IV is transformed to.

  /// Kind and binary operator of the induction.

  const InductionDescriptor::InductionKind Kind;

  const BinaryOperator *BinOp;



public:

  VPDerivedIVRecipe(const InductionDescriptor &IndDesc, VPValue *Start,

                    VPCanonicalIVPHIRecipe *CanonicalIV, VPValue *Step,

                    Type *ResultTy)

                    Type *TruncResultTy)

      : VPRecipeBase(VPDef::VPDerivedIVSC, {Start, CanonicalIV, Step}),

        VPValue(this), ResultTy(ResultTy),

        IsTruncated(IndDesc.getStep()->getType() != ResultTy),

        Kind(IndDesc.getKind()), BinOp(IndDesc.getInductionBinOp()) {}

        VPValue(this), TruncResultTy(TruncResultTy), Kind(IndDesc.getKind()),

        BinOp(IndDesc.getInductionBinOp()) {}



  ~VPDerivedIVRecipe() override = default;

llvm/lib/Transforms/Vectorize/VPlanRecipes.cpp

+2 −2
Original line number Diff line number Diff line
@@ -797,8 +797,8 @@ void VPDerivedIVRecipe::print(raw_ostream &O, const Twine &Indent, 
  O << " * ";

  getStepValue()->printAsOperand(O, SlotTracker);



  if (IsTruncated)

    O << " (truncated to " << *ResultTy << ")";

  if (TruncResultTy)

    O << " (truncated to " << *TruncResultTy << ")";

}

#endif

llvm/lib/Transforms/Vectorize/VPlanTransforms.cpp

+2 −1
Original line number Diff line number Diff line
@@ -511,7 +511,8 @@ static VPValue *createScalarIVSteps(VPlan &Plan, const InductionDescriptor &ID, 
  Type *TruncTy = TruncI ? TruncI->getType() : IVTy;

  VPValue *BaseIV = CanonicalIV;

  if (!CanonicalIV->isCanonical(ID.getKind(), StartV, Step, TruncTy)) {

    BaseIV = new VPDerivedIVRecipe(ID, StartV, CanonicalIV, Step, TruncTy);

    BaseIV = new VPDerivedIVRecipe(ID, StartV, CanonicalIV, Step,

                                   TruncI ? TruncI->getType() : nullptr);

    HeaderVPBB->insert(BaseIV->getDefiningRecipe(), IP);

  }