Merge pull request #5852 from zjaffal/stable/20220421

Revert "[AArch64] Fix cost model for `udiv` instruction when one of t…

Author: zjaffal

llvm/lib/Target/AArch64/AArch64TargetTransformInfo.cpp

@@ -1835,18 +1835,6 @@ InstructionCost AArch64TTIImpl::getArithmeticInstrCost(
     InstructionCost Cost = BaseT::getArithmeticInstrCost(
         Opcode, Ty, CostKind, Opd1Info, Opd2Info, Opd1PropInfo, Opd2PropInfo);
     if (Ty->isVectorTy()) {
-      // If one of the operands is a uniform constant then the cost for each
-      // element is Cost for insertion, extraction and division.
-      // Insertion cost = 2, Extraction Cost = 2, Division = cost for the
-      // operation with scalar type
-      if ( Opd1Info == TargetTransformInfo::OK_UniformConstantValue ||
-          Opd2Info == TargetTransformInfo::OK_UniformConstantValue) {
-        if (auto *VTy = dyn_cast<FixedVectorType>(Ty)) {
-          InstructionCost DivCost = BaseT::getArithmeticInstrCost(
-              Opcode, Ty->getScalarType(), CostKind, Opd1Info, Opd2Info);
-          return (4 + DivCost) * VTy->getNumElements();
-        }
-      }
       // On AArch64, vector divisions are not supported natively and are
       // expanded into scalar divisions of each pair of elements.
       Cost += getArithmeticInstrCost(Instruction::ExtractElement, Ty, CostKind,