code: func buildBitXor(aggFuncDesc *aggregation.AggFuncDesc, ordinal int) AggFunc {
  	base := baseAggFunc{
  		args:    aggFuncDesc.Args,
  		ordinal: ordinal,
  	}
  	return &bitXorUint64{baseBitAggFunc{base}}
  }
docs: // buildBitXor builds the AggFunc implementation for function "BIT_XOR".