[LegalizeTypes][NFC] Use getConstantOperandVal instead of cast constant getvalue.

[Jimerlife]

Summary

Use getConstantOperandVal(Num) API instead of cast<ConstantSDNode>(N->getOperand(Num))->getZExtValue().

[craig.topper]

llvm/lib/CodeGen/SelectionDAG/LegalizeFloatTypes.cpp

2367 ↗

(On Diff #451712)

Not sure that I like that we repeated the "1" here when we already have Idx. It's potentially more code too since we need to dereference N again.

[RKSimon]

llvm/lib/CodeGen/SelectionDAG/LegalizeFloatTypes.cpp

2367 ↗

(On Diff #451712)

+1 We've tended to avoid using getConstantOperand helpers when we're also accessing the raw getOperand() variant - probably just do this in cases where we can then remove the getOperand call

[Jimerlife]

address comment

[Jimerlife]

Only use getConstantOperandVal(Num) API instead of cast<ConstantSDNode>(N->getOperand(Num))->getZExtValue(). If We already have Idx, still keeping origin cast form. Thanks your suggestions @craig.topper @RKSimon.

[craig.topper]

LGTM

llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp

case ISD::VECTOR_SHUFFLE: {
     break;
   }
   case ISD::VECTOR_SPLICE: {
     Results.push_back(TLI.expandVectorSplice(Node, DAG));
     break;
   }
   case ISD::EXTRACT_ELEMENT: {
     EVT OpTy = Node->getOperand(0).getValueType();
-    if (cast<ConstantSDNode>(Node->getOperand(1))->getZExtValue()) {
+    if (Node->getConstantOperandVal(1)) {
       // 1 -> Hi
       Tmp1 = DAG.getNode(ISD::SRL, dl, OpTy, Node->getOperand(0),
                          DAG.getConstant(OpTy.getSizeInBits() / 2, dl,
                                          TLI.getShiftAmountTy(
                                              Node->getOperand(0).getValueType(),
                                              DAG.getDataLayout())));
       Tmp1 = DAG.getNode(ISD::TRUNCATE, dl, Node->getValueType(0), Tmp1);
     } else {

llvm/lib/CodeGen/SelectionDAG/LegalizeTypesGeneric.cpp

void DAGTypeLegalizer::ExpandRes_BUILD_PAIR(SDNode *N, SDValue &Lo,
   // Return the operands.
   Lo = N->getOperand(0);
   Hi = N->getOperand(1);
 }
 
 void DAGTypeLegalizer::ExpandRes_EXTRACT_ELEMENT(SDNode *N, SDValue &Lo,
                                                  SDValue &Hi) {
   GetExpandedOp(N->getOperand(0), Lo, Hi);
-  SDValue Part = cast<ConstantSDNode>(N->getOperand(1))->getZExtValue() ?
-                   Hi : Lo;
+  SDValue Part = N->getConstantOperandVal(1) ? Hi : Lo;
 
   assert(Part.getValueType() == N->getValueType(0) &&
          "Type twice as big as expanded type not itself expanded!");
 
   GetPairElements(Part, Lo, Hi);
 }
 
 void DAGTypeLegalizer::ExpandRes_EXTRACT_VECTOR_ELT(SDNode *N, SDValue &Lo,
SDValue DAGTypeLegalizer::ExpandOp_BUILD_VECTOR(SDNode *N) {
 
   // Convert the new vector to the old vector type.
   return DAG.getNode(ISD::BITCAST, dl, VecVT, NewVec);
 }
 
 SDValue DAGTypeLegalizer::ExpandOp_EXTRACT_ELEMENT(SDNode *N) {
   SDValue Lo, Hi;
   GetExpandedOp(N->getOperand(0), Lo, Hi);
-  return cast<ConstantSDNode>(N->getOperand(1))->getZExtValue() ? Hi : Lo;
+  return N->getConstantOperandVal(1) ? Hi : Lo;
 }
 
 SDValue DAGTypeLegalizer::ExpandOp_INSERT_VECTOR_ELT(SDNode *N) {
   // The vector type is legal but the element type needs expansion.
   EVT VecVT = N->getValueType(0);
   unsigned NumElts = VecVT.getVectorNumElements();
   SDLoc dl(N);