[LegalizeTypes] Remove WidenVecRes_Shift and just use WidenVecRes_Binary

[craig.topper]

Summary

This function seems to allow for the shift amount to have a different type than the result, but I don't think we do that anywhere else for vector shifts. We also don't have any support for legalizing the shift amount alone if the result is legal and the shift amount type isn't. The code coverage report here shows this code as uncovered http://lab.llvm.org:8080/coverage/coverage-reports/coverage/Users/buildslave/jenkins/workspace/coverage/llvm-project/llvm/lib/CodeGen/SelectionDAG/LegalizeVectorTypes.cpp.html

[RKSimon]

LGTM

llvm/lib/CodeGen/SelectionDAG/LegalizeTypes.h

private:
   SDValue WidenVecRes_BinaryCanTrap(SDNode *N);
   SDValue WidenVecRes_BinaryWithExtraScalarOp(SDNode *N);
   SDValue WidenVecRes_StrictFP(SDNode *N);
   SDValue WidenVecRes_OverflowOp(SDNode *N, unsigned ResNo);
   SDValue WidenVecRes_Convert(SDNode *N);
   SDValue WidenVecRes_Convert_StrictFP(SDNode *N);
   SDValue WidenVecRes_FCOPYSIGN(SDNode *N);
   SDValue WidenVecRes_POWI(SDNode *N);
-  SDValue WidenVecRes_Shift(SDNode *N);
   SDValue WidenVecRes_Unary(SDNode *N);
   SDValue WidenVecRes_InregOp(SDNode *N);
 
   // Widen Vector Operand.
   bool WidenVectorOperand(SDNode *N, unsigned OpNo);
   SDValue WidenVecOp_BITCAST(SDNode *N);
   SDValue WidenVecOp_CONCAT_VECTORS(SDNode *N);
   SDValue WidenVecOp_EXTEND(SDNode *N);

llvm/lib/CodeGen/SelectionDAG/LegalizeVectorTypes.cpp

#endif
   case ISD::ADD:
   case ISD::AND:
   case ISD::MUL:
   case ISD::MULHS:
   case ISD::MULHU:
   case ISD::OR:
   case ISD::SUB:
   case ISD::XOR:
+  case ISD::SHL:
+  case ISD::SRA:
+  case ISD::SRL:
   case ISD::FMINNUM:
   case ISD::FMAXNUM:
   case ISD::FMINIMUM:
   case ISD::FMAXIMUM:
   case ISD::SMIN:
   case ISD::SMAX:
   case ISD::UMIN:
   case ISD::UMAX:
#include "llvm/IR/ConstrainedOps.def"
   case ISD::FCOPYSIGN:
     Res = WidenVecRes_FCOPYSIGN(N);
     break;
 
   case ISD::FPOWI:
     Res = WidenVecRes_POWI(N);
     break;
 
-  case ISD::SHL:
-  case ISD::SRA:
-  case ISD::SRL:
-    Res = WidenVecRes_Shift(N);
-    break;
-
   case ISD::ANY_EXTEND_VECTOR_INREG:
   case ISD::SIGN_EXTEND_VECTOR_INREG:
   case ISD::ZERO_EXTEND_VECTOR_INREG:
     Res = WidenVecRes_EXTEND_VECTOR_INREG(N);
     break;
 
   case ISD::ANY_EXTEND:
   case ISD::FP_EXTEND:

 
 SDValue DAGTypeLegalizer::WidenVecRes_POWI(SDNode *N) {
   EVT WidenVT = TLI.getTypeToTransformTo(*DAG.getContext(), N->getValueType(0));
   SDValue InOp = GetWidenedVector(N->getOperand(0));
   SDValue ShOp = N->getOperand(1);
   return DAG.getNode(N->getOpcode(), SDLoc(N), WidenVT, InOp, ShOp);
 }
 
-SDValue DAGTypeLegalizer::WidenVecRes_Shift(SDNode *N) {
-  EVT WidenVT = TLI.getTypeToTransformTo(*DAG.getContext(), N->getValueType(0));
-  SDValue InOp = GetWidenedVector(N->getOperand(0));
-  SDValue ShOp = N->getOperand(1);
-
-  EVT ShVT = ShOp.getValueType();
-  if (getTypeAction(ShVT) == TargetLowering::TypeWidenVector) {
-    ShOp = GetWidenedVector(ShOp);
-    ShVT = ShOp.getValueType();
-  }
-  EVT ShWidenVT = EVT::getVectorVT(*DAG.getContext(),
-                                   ShVT.getVectorElementType(),
-                                   WidenVT.getVectorNumElements());
-  if (ShVT != ShWidenVT)
-    ShOp = ModifyToType(ShOp, ShWidenVT);
-
-  return DAG.getNode(N->getOpcode(), SDLoc(N), WidenVT, InOp, ShOp);
-}
-
 SDValue DAGTypeLegalizer::WidenVecRes_Unary(SDNode *N) {
   // Unary op widening.
   EVT WidenVT = TLI.getTypeToTransformTo(*DAG.getContext(), N->getValueType(0));
   SDValue InOp = GetWidenedVector(N->getOperand(0));
   return DAG.getNode(N->getOpcode(), SDLoc(N), WidenVT, InOp);
 }
 
 SDValue DAGTypeLegalizer::WidenVecRes_InregOp(SDNode *N) {