doris/be/src/vec/aggregate_functions/aggregate_function_bitmap.h

// Licensed to the Apache Software Foundation (ASF) under one
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// distributed with this work for additional information
// regarding copyright ownership.  The ASF licenses this file
// to you under the Apache License, Version 2.0 (the
// "License"); you may not use this file except in compliance
// with the License.  You may obtain a copy of the License at
//
//   http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing,
// software distributed under the License is distributed on an
// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
// KIND, either express or implied.  See the License for the
// specific language governing permissions and limitations
// under the License.

#pragma once

#include "vec/aggregate_functions/aggregate_function.h"
#include "vec/columns/column_complex.h"
#include "vec/columns/column_nullable.h"
#include "vec/common/assert_cast.h"
#include "vec/data_types/data_type_bitmap.h"
#include "vec/data_types/data_type_nullable.h"
#include "vec/data_types/data_type_number.h"
#include "vec/io/io_helper.h"

namespace doris::vectorized {

struct AggregateFunctionBitmapUnionOp {
    static constexpr auto name = "bitmap_union";

    template <typename T>
    static void add(BitmapValue& res, const T& data, bool& is_first) {
        res.add(data);
    }

    static void add(BitmapValue& res, const BitmapValue& data, bool& is_first) {
        if (UNLIKELY(is_first)) {
            res = data;
            is_first = false;
        } else {
            res |= data;
        }
    }

    static void merge(BitmapValue& res, const BitmapValue& data, bool& is_first) {
        if (UNLIKELY(is_first)) {
            res = data;
            is_first = false;
        } else {
            res |= data;
        }
    }
};

struct AggregateFunctionBitmapIntersectOp {
    static constexpr auto name = "bitmap_intersect";

    static void add(BitmapValue& res, const BitmapValue& data, bool& is_first) {
        if (UNLIKELY(is_first)) {
            res = data;
            is_first = false;
        } else {
            res &= data;
        }
    }

    static void merge(BitmapValue& res, const BitmapValue& data, bool& is_first) {
        if (UNLIKELY(is_first)) {
            res = data;
            is_first = false;
        } else {
            res &= data;
        }
    }
};

template <typename Op>
struct AggregateFunctionBitmapData {
    BitmapValue value;
    bool is_first = true;

    template <typename T>
    void add(const T& data) {
        Op::add(value, data, is_first);
    }

    void merge(const BitmapValue& data) { Op::merge(value, data, is_first); }

    void write(BufferWritable& buf) const { DataTypeBitMap::serialize_as_stream(value, buf); }

    void read(BufferReadable& buf) { DataTypeBitMap::deserialize_as_stream(value, buf); }

    void reset() { is_first = true; }

    BitmapValue& get() { return value; }
};

template <typename Op>
class AggregateFunctionBitmapOp final
        : public IAggregateFunctionDataHelper<AggregateFunctionBitmapData<Op>,
                                              AggregateFunctionBitmapOp<Op>> {
public:
    using ResultDataType = BitmapValue;
    using ColVecType = ColumnBitmap;
    using ColVecResult = ColumnBitmap;

    String get_name() const override { return Op::name; }

    AggregateFunctionBitmapOp(const DataTypes& argument_types_)
            : IAggregateFunctionDataHelper<AggregateFunctionBitmapData<Op>,
                                           AggregateFunctionBitmapOp<Op>>(argument_types_, {}) {}

    DataTypePtr get_return_type() const override { return std::make_shared<DataTypeBitMap>(); }

    void add(AggregateDataPtr __restrict place, const IColumn** columns, size_t row_num,
             Arena*) const override {
        const auto& column = static_cast<const ColVecType&>(*columns[0]);
        this->data(place).add(column.get_data()[row_num]);
    }

    void merge(AggregateDataPtr __restrict place, ConstAggregateDataPtr rhs,
               Arena*) const override {
        this->data(place).merge(
                const_cast<AggregateFunctionBitmapData<Op>&>(this->data(rhs)).get());
    }

    void serialize(ConstAggregateDataPtr __restrict place, BufferWritable& buf) const override {
        this->data(place).write(buf);
    }

    void deserialize(AggregateDataPtr __restrict place, BufferReadable& buf,
                     Arena*) const override {
        this->data(place).read(buf);
    }

    void insert_result_into(ConstAggregateDataPtr __restrict place, IColumn& to) const override {
        auto& column = static_cast<ColVecResult&>(to);
        column.get_data().push_back(
                const_cast<AggregateFunctionBitmapData<Op>&>(this->data(place)).get());
    }

    void reset(AggregateDataPtr __restrict place) const override { this->data(place).reset(); }
};

template <bool nullable, typename ColVecType>
class AggregateFunctionBitmapCount final
        : public IAggregateFunctionDataHelper<
                  AggregateFunctionBitmapData<AggregateFunctionBitmapUnionOp>,
                  AggregateFunctionBitmapCount<nullable, ColVecType>> {
public:
    // using ColVecType = ColumnBitmap;
    using ColVecResult = ColumnVector<Int64>;
    using AggFunctionData = AggregateFunctionBitmapData<AggregateFunctionBitmapUnionOp>;

    AggregateFunctionBitmapCount(const DataTypes& argument_types_)
            : IAggregateFunctionDataHelper<
                      AggregateFunctionBitmapData<AggregateFunctionBitmapUnionOp>,
                      AggregateFunctionBitmapCount<nullable, ColVecType>>(argument_types_, {}) {}

    String get_name() const override { return "count"; }
    DataTypePtr get_return_type() const override { return std::make_shared<DataTypeInt64>(); }

    void add(AggregateDataPtr __restrict place, const IColumn** columns, size_t row_num,
             Arena*) const override {
        if constexpr (nullable) {
            auto& nullable_column = assert_cast<const ColumnNullable&>(*columns[0]);
            if (!nullable_column.is_null_at(row_num)) {
                const auto& column =
                        static_cast<const ColVecType&>(nullable_column.get_nested_column());
                this->data(place).add(column.get_data()[row_num]);
            }
        } else {
            const auto& column = static_cast<const ColVecType&>(*columns[0]);
            this->data(place).add(column.get_data()[row_num]);
        }
    }

    void merge(AggregateDataPtr __restrict place, ConstAggregateDataPtr rhs,
               Arena*) const override {
        this->data(place).merge(const_cast<AggFunctionData&>(this->data(rhs)).get());
    }

    void serialize(ConstAggregateDataPtr __restrict place, BufferWritable& buf) const override {
        this->data(place).write(buf);
    }

    void deserialize(AggregateDataPtr __restrict place, BufferReadable& buf,
                     Arena*) const override {
        this->data(place).read(buf);
    }

    void insert_result_into(ConstAggregateDataPtr __restrict place, IColumn& to) const override {
        auto& value_data = const_cast<AggFunctionData&>(this->data(place)).get();
        auto& column = static_cast<ColVecResult&>(to);
        column.get_data().push_back(value_data.cardinality());
    }

    void reset(AggregateDataPtr __restrict place) const override { this->data(place).reset(); }
};

AggregateFunctionPtr create_aggregate_function_bitmap_union(const std::string& name,
                                                            const DataTypes& argument_types,
                                                            const Array& parameters,
                                                            const bool result_is_nullable);

} // namespace doris::vectorized