Clean up usages of asserting vector getters in Type

[ctetreau]

Summary

Remove usages of asserting vector getters in Type in preparation for the
VectorType refactor. The existence of these functions complicates the
refactor while adding little value.

[ctetreau]

Update to mention that this is NFC

[efriedma]

LGTM with one minor suggestion.

llvm/lib/Target/Hexagon/HexagonISelLowering.cpp

1090

ConstantVector::getType() actually returns a VectorType; the cast<> isn't necessary.

llvm/lib/Target/Hexagon/HexagonISelLowering.cpp

 
 SDValue
 HexagonTargetLowering::LowerConstantPool(SDValue Op, SelectionDAG &DAG) const {
   EVT ValTy = Op.getValueType();
   ConstantPoolSDNode *CPN = cast<ConstantPoolSDNode>(Op);
   Constant *CVal = nullptr;
   bool isVTi1Type = false;
   if (auto *CV = dyn_cast<ConstantVector>(CPN->getConstVal())) {
-    if (CV->getType()->getVectorElementType()->isIntegerTy(1)) {
+    if (cast<VectorType>(CV->getType())->getElementType()->isIntegerTy(1)) {
       IRBuilder<> IRB(CV->getContext());
       SmallVector<Constant*, 128> NewConst;
       unsigned VecLen = CV->getNumOperands();
       assert(isPowerOf2_32(VecLen) &&
              "conversion only supported for pow2 VectorSize");
       for (unsigned i = 0; i < VecLen; ++i)
         NewConst.push_back(IRB.getInt8(CV->getOperand(i)->isZeroValue()));
 

llvm/lib/Target/Hexagon/HexagonTargetTransformInfo.cpp

if (!VecVT.isSimple() || VecVT.getSizeInBits() <= 64)
     return false;
   if (ST.isHVXVectorType(VecVT.getSimpleVT()))
     return true;
   auto Action = TLI.getPreferredVectorAction(VecVT.getSimpleVT());
   return Action == TargetLoweringBase::TypeWidenVector;
 }
 
 unsigned HexagonTTIImpl::getTypeNumElements(Type *Ty) const {
-  if (Ty->isVectorTy())
-    return Ty->getVectorNumElements();
+  if (auto *VTy = dyn_cast<VectorType>(Ty))
+    return VTy->getNumElements();
   assert((Ty->isIntegerTy() || Ty->isFloatingPointTy()) &&
          "Expecting scalar type");
   return 1;
 }
 
 TargetTransformInfo::PopcntSupportKind
 HexagonTTIImpl::getPopcntSupport(unsigned IntTyWidthInBit) const {
   // Return fast hardware support as every input < 64 bits will be promoted