C++ LLT::getScalarSizeInBits方法代码示例

std::pair<LegalizerInfo::LegalizeAction, LLT>
LegalizerInfo::findVectorLegalAction(const InstrAspect &Aspect) const {
  assert(Aspect.Type.isVector());
  // First legalize the vector element size, then legalize the number of
  // lanes in the vector.
  if (Aspect.Opcode < FirstOp || Aspect.Opcode > LastOp)
    return {NotFound, Aspect.Type};
  const unsigned OpcodeIdx = Aspect.Opcode - FirstOp;
  const unsigned TypeIdx = Aspect.Idx;
  if (TypeIdx >= ScalarInVectorActions[OpcodeIdx].size())
    return {NotFound, Aspect.Type};
  const SizeAndActionsVec &ElemSizeVec =
      ScalarInVectorActions[OpcodeIdx][TypeIdx];

  LLT IntermediateType;
  auto ElementSizeAndAction =
      findAction(ElemSizeVec, Aspect.Type.getScalarSizeInBits());
  IntermediateType =
      LLT::vector(Aspect.Type.getNumElements(), ElementSizeAndAction.first);
  if (ElementSizeAndAction.second != Legal)
    return {ElementSizeAndAction.second, IntermediateType};

  auto i = NumElements2Actions[OpcodeIdx].find(
      IntermediateType.getScalarSizeInBits());
  if (i == NumElements2Actions[OpcodeIdx].end()) {
    return {NotFound, IntermediateType};
  }
  const SizeAndActionsVec &NumElementsVec = (*i).second[TypeIdx];
  auto NumElementsAndAction =
      findAction(NumElementsVec, IntermediateType.getNumElements());
  return {NumElementsAndAction.second,
          LLT::vector(NumElementsAndAction.first,
                      IntermediateType.getScalarSizeInBits())};
}

// Make sure the returned mutation makes sense for the match type.
static bool mutationIsSane(const LegalizeRule &Rule,
                           const LegalityQuery &Q,
                           std::pair<unsigned, LLT> Mutation) {
  const unsigned TypeIdx = Mutation.first;
  const LLT OldTy = Q.Types[TypeIdx];
  const LLT NewTy = Mutation.second;

  switch (Rule.getAction()) {
  case FewerElements:
  case MoreElements: {
    if (!OldTy.isVector())
      return false;

    if (NewTy.isVector()) {
      if (Rule.getAction() == FewerElements) {
        // Make sure the element count really decreased.
        if (NewTy.getNumElements() >= OldTy.getNumElements())
          return false;
      } else {
        // Make sure the element count really increased.
        if (NewTy.getNumElements() <= OldTy.getNumElements())
          return false;
      }
    }

    // Make sure the element type didn't change.
    return NewTy.getScalarType() == OldTy.getElementType();
  }
  case NarrowScalar:
  case WidenScalar: {
    if (OldTy.isVector()) {
      // Number of elements should not change.
      if (!NewTy.isVector() || OldTy.getNumElements() != NewTy.getNumElements())
        return false;
    } else {
      // Both types must be vectors
      if (NewTy.isVector())
        return false;
    }

    if (Rule.getAction() == NarrowScalar)  {
      // Make sure the size really decreased.
      if (NewTy.getScalarSizeInBits() >= OldTy.getScalarSizeInBits())
        return false;
    } else {
      // Make sure the size really increased.
      if (NewTy.getScalarSizeInBits() <= OldTy.getScalarSizeInBits())
        return false;
    }

    return true;
  }
  default:
    return true;
  }
}

LegalizeMutation LegalizeMutations::widenScalarOrEltToNextPow2(unsigned TypeIdx,
                                                               unsigned Min) {
  return [=](const LegalityQuery &Query) {
    const LLT Ty = Query.Types[TypeIdx];
    unsigned NewEltSizeInBits =
        std::max(1u << Log2_32_Ceil(Ty.getScalarSizeInBits()), Min);
    return std::make_pair(TypeIdx, Ty.changeElementSize(NewEltSizeInBits));
  };
}

//.........这里部分代码省略.........
      .legalIf([=](const LegalityQuery &Query) {
          const LLT &VecTy = Query.Types[VecTypeIdx];
          const LLT &IdxTy = Query.Types[IdxTypeIdx];
          return VecTy.getSizeInBits() % 32 == 0 &&
            VecTy.getSizeInBits() <= 512 &&
            IdxTy.getSizeInBits() == 32;
        })
      .clampScalar(EltTypeIdx, S32, S64)
      .clampScalar(VecTypeIdx, S32, S64)
      .clampScalar(IdxTypeIdx, S32, S32);
  }

  getActionDefinitionsBuilder(G_EXTRACT_VECTOR_ELT)
    .unsupportedIf([=](const LegalityQuery &Query) {
        const LLT &EltTy = Query.Types[1].getElementType();
        return Query.Types[0] != EltTy;
      });

  for (unsigned Op : {G_EXTRACT, G_INSERT}) {
    unsigned BigTyIdx = Op == G_EXTRACT ? 1 : 0;
    unsigned LitTyIdx = Op == G_EXTRACT ? 0 : 1;

    // FIXME: Doesn't handle extract of illegal sizes.
    getActionDefinitionsBuilder(Op)
      .legalIf([=](const LegalityQuery &Query) {
          const LLT BigTy = Query.Types[BigTyIdx];
          const LLT LitTy = Query.Types[LitTyIdx];
          return (BigTy.getSizeInBits() % 32 == 0) &&
                 (LitTy.getSizeInBits() % 16 == 0);
        })
      .widenScalarIf(
        [=](const LegalityQuery &Query) {
          const LLT BigTy = Query.Types[BigTyIdx];
          return (BigTy.getScalarSizeInBits() < 16);
        },
        LegalizeMutations::widenScalarOrEltToNextPow2(BigTyIdx, 16))
      .widenScalarIf(
        [=](const LegalityQuery &Query) {
          const LLT LitTy = Query.Types[LitTyIdx];
          return (LitTy.getScalarSizeInBits() < 16);
        },
        LegalizeMutations::widenScalarOrEltToNextPow2(LitTyIdx, 16))
      .moreElementsIf(isSmallOddVector(BigTyIdx), oneMoreElement(BigTyIdx))
      .widenScalarToNextPow2(BigTyIdx, 32);

  }

  // TODO: vectors of pointers
  getActionDefinitionsBuilder(G_BUILD_VECTOR)
      .legalForCartesianProduct(AllS32Vectors, {S32})
      .legalForCartesianProduct(AllS64Vectors, {S64})
      .clampNumElements(0, V16S32, V16S32)
      .clampNumElements(0, V2S64, V8S64)
      .minScalarSameAs(1, 0)
      // FIXME: Sort of a hack to make progress on other legalizations.
      .legalIf([=](const LegalityQuery &Query) {
        return Query.Types[0].getScalarSizeInBits() <= 32 ||
               Query.Types[0].getScalarSizeInBits() == 64;
      });

  // TODO: Support any combination of v2s32
  getActionDefinitionsBuilder(G_CONCAT_VECTORS)
    .legalFor({{V4S32, V2S32},
               {V8S32, V2S32},
               {V8S32, V4S32},
               {V4S64, V2S64},