1. Fix the bug of sort node return empty block if child eos is true a…

…nd add some comment (apache#23)

2. Use SIMD to speed up has_null() in column nullable
3. Support UDAF of avg

Change-Id: I13846d7275e1cc37085d3afbf41d60261e296662

Co-authored-by: lihaopeng <lihaopeng@baidu.com>

be/src/vec/CMakeLists.txt

@@ -24,6 +24,7 @@ set(VEC_FILES
   aggregate_functions/aggregate_function_null.cpp
   aggregate_functions/aggregate_function_sum.cpp
   aggregate_functions/aggregate_function_min_max.cpp
+  aggregate_functions/aggregate_function_avg.cpp
   columns/collator.cpp
   columns/column.cpp
   columns/column_const.cpp

be/src/vec/aggregate_functions/aggregate_function_avg.cpp

@@ -0,0 +1,50 @@
+#include "vec/aggregate_functions/aggregate_function_simple_factory.h"
+#include "vec/aggregate_functions/aggregate_function_avg.h"
+#include "vec/aggregate_functions/helpers.h"
+#include "vec/aggregate_functions/factory_helpers.h"
+
+namespace doris::vectorized
+{
+
+namespace
+{
+
+template <typename T>
+struct Avg
+{
+    using FieldType = std::conditional_t<IsDecimalNumber<T>, Decimal128, NearestFieldType<T>>;
+    using Function = AggregateFunctionAvg<T, AggregateFunctionAvgData<FieldType>>;
+};
+
+template <typename T>
+using AggregateFuncAvg = typename Avg<T>::Function;
+
+AggregateFunctionPtr createAggregateFunctionAvg(const std::string & name, const DataTypes & argument_types, const Array & parameters)
+{
+    assertNoParameters(name, parameters);
+    assertUnary(name, argument_types);
+
+    AggregateFunctionPtr res;
+    DataTypePtr data_type = argument_types[0];
+    if (isDecimal(data_type))
+        res.reset(createWithDecimalType<AggregateFuncAvg>(*data_type, *data_type, argument_types));
+    else
+        res.reset(createWithNumericType<AggregateFuncAvg>(*data_type, argument_types));
+
+    if (!res)
+        throw Exception("Illegal type " + argument_types[0]->getName() + " of argument for aggregate function " + name,
+                        ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT);
+    return res;
+}
+
+}
+
+//void registerAggregateFunctionAvg(AggregateFunctionFactory & factory)
+//{
+//    factory.registerFunction("avg", createAggregateFunctionAvg, AggregateFunctionFactory::CaseInsensitive);
+//}
+
+void registerAggregateFunctionAvg(AggregateFunctionSimpleFactory& factory) {
+    factory.registerFunction("avg", createAggregateFunctionAvg);
+}
+}

be/src/vec/aggregate_functions/aggregate_function_avg.h

@@ -0,0 +1,115 @@
+#pragma once
+
+#include "vec/data_types/data_types_number.h"
+#include "vec/data_types/data_types_decimal.h"
+#include "vec/columns/columns_number.h"
+#include "vec/aggregate_functions/aggregate_function.h"
+#include "vec/io/io_helper.h"
+
+namespace doris::vectorized
+{
+
+namespace ErrorCodes
+{
+    extern const int LOGICAL_ERROR;
+}
+
+template <typename T>
+struct AggregateFunctionAvgData
+{
+    T sum = 0;
+    UInt64 count = 0;
+
+    template <typename ResultT>
+    ResultT NO_SANITIZE_UNDEFINED result() const
+    {
+        if constexpr (std::is_floating_point_v<ResultT>)
+            if constexpr (std::numeric_limits<ResultT>::is_iec559)
+                return static_cast<ResultT>(sum) / count; /// allow division by zero
+
+        if (!count)
+            throw Exception("AggregateFunctionAvg with zero values", ErrorCodes::LOGICAL_ERROR);
+        return static_cast<ResultT>(sum) / count;
+    }
+
+    void write(std::ostream& buf) const {
+        writeBinary(sum, buf);
+        writeBinary(count, buf);
+    }
+
+    void read(std::istream& buf) {
+        readBinary(sum, buf);
+        readBinary(count, buf);
+    }
+};
+
+
+/// Calculates arithmetic mean of numbers.
+template <typename T, typename Data>
+class AggregateFunctionAvg final : public IAggregateFunctionDataHelper<Data, AggregateFunctionAvg<T, Data>>
+{
+public:
+    using ResultType = std::conditional_t<IsDecimalNumber<T>, Decimal128, Float64>;
+    using ResultDataType = std::conditional_t<IsDecimalNumber<T>, DataTypeDecimal<Decimal128>, DataTypeNumber<Float64>>;
+    using ColVecType = std::conditional_t<IsDecimalNumber<T>, ColumnDecimal<T>, ColumnVector<T>>;
+    using ColVecResult = std::conditional_t<IsDecimalNumber<T>, ColumnDecimal<Decimal128>, ColumnVector<Float64>>;
+
+    /// ctor for native types
+    AggregateFunctionAvg(const DataTypes & argument_types_)
+        : IAggregateFunctionDataHelper<Data, AggregateFunctionAvg<T, Data>>(argument_types_, {})
+        , scale(0)
+    {}
+
+    /// ctor for Decimals
+    AggregateFunctionAvg(const IDataType & data_type, const DataTypes & argument_types_)
+        : IAggregateFunctionDataHelper<Data, AggregateFunctionAvg<T, Data>>(argument_types_, {})
+        , scale(getDecimalScale(data_type))
+    {}
+
+    String getName() const override { return "avg"; }
+
+    DataTypePtr getReturnType() const override
+    {
+        if constexpr (IsDecimalNumber<T>)
+            return std::make_shared<ResultDataType>(ResultDataType::maxPrecision(), scale);
+        else
+            return std::make_shared<ResultDataType>();
+    }
+
+    void add(AggregateDataPtr place, const IColumn ** columns, size_t row_num, Arena *) const override
+    {
+        const auto & column = static_cast<const ColVecType &>(*columns[0]);
+        this->data(place).sum += column.getData()[row_num];
+        ++this->data(place).count;
+    }
+
+    void merge(AggregateDataPtr place, ConstAggregateDataPtr rhs, Arena *) const override
+    {
+        this->data(place).sum += this->data(rhs).sum;
+        this->data(place).count += this->data(rhs).count;
+    }
+
+    void serialize(ConstAggregateDataPtr place, std::ostream& buf) const override
+    {
+        this->data(place).write(buf);
+    }
+
+    void deserialize(AggregateDataPtr place, std::istream& buf, Arena *) const override
+    {
+        this->data(place).read(buf);
+    }
+
+    void insertResultInto(ConstAggregateDataPtr place, IColumn & to) const override
+    {
+        auto & column = static_cast<ColVecResult &>(to);
+        column.getData().push_back(this->data(place).template result<ResultType>());
+    }
+
+    const char * getHeaderFilePath() const override { return __FILE__; }
+
+private:
+    UInt32 scale;
+};
+
+
+}

be/src/vec/aggregate_functions/aggregate_function_null.cpp

@@ -104,6 +104,7 @@ void registerAggregateFunctionCombinatorNull(AggregateFunctionSimpleFactory& fac
     factory.registerFunction("sum", creator, true);
     factory.registerFunction("max", creator, true);
     factory.registerFunction("min", creator, true);
+    factory.registerFunction("avg", creator, true);
 }
 
 } // namespace doris::vectorized

be/src/vec/aggregate_functions/aggregate_function_simple_factory.h

@@ -33,6 +33,7 @@ class AggregateFunctionSimpleFactory;
 void registerAggregateFunctionSum(AggregateFunctionSimpleFactory& factory);
 void registerAggregateFunctionCombinatorNull(AggregateFunctionSimpleFactory& factory);
 void registerAggregateFunctionMinMax(AggregateFunctionSimpleFactory& factory);
+void registerAggregateFunctionAvg(AggregateFunctionSimpleFactory& factory);
 
 using DataTypePtr = std::shared_ptr<const IDataType>;
 using DataTypes = std::vector<DataTypePtr>;
@@ -82,6 +83,7 @@ class AggregateFunctionSimpleFactory {
         std::call_once(oc, [&]() {
             registerAggregateFunctionSum(instance);
             registerAggregateFunctionMinMax(instance);
+            registerAggregateFunctionAvg(instance);
             registerAggregateFunctionCombinatorNull(instance);
         });
         return instance;

be/src/vec/columns/column_nullable.h

@@ -159,13 +159,34 @@ class ColumnNullable final : public COWHelper<IColumn, ColumnNullable> {
     void checkConsistency() const;
 
     bool has_null() const {
-        auto begin = getNullMapData().begin();
-        auto end = getNullMapData().end();
-        while (begin < end) {
-            if (*begin != 0) {
-                return *begin;
+        size_t size = getNullMapData().size();
+        const UInt8* null_pos = getNullMapData().data();
+        const UInt8* null_pos_end = getNullMapData().data() + size;
+ #ifdef __SSE2__
+    /** A slightly more optimized version.
+        * Based on the assumption that often pieces of consecutive values
+        *  completely pass or do not pass the filter.
+        * Therefore, we will optimistically check the parts of `SIMD_BYTES` values.
+        */
+        static constexpr size_t SIMD_BYTES = 16;
+        const __m128i zero16 = _mm_setzero_si128();
+        const UInt8* null_end_sse = null_pos + size / SIMD_BYTES * SIMD_BYTES;
+
+        while (null_pos < null_end_sse) {
+            int mask = _mm_movemask_epi8(_mm_cmpgt_epi8(
+                _mm_loadu_si128(reinterpret_cast<const __m128i*>(null_pos)), zero16));
+
+            if (0 != mask) {
+                return true;
             }
-            ++begin;
+            null_pos += SIMD_BYTES;
+        }
+#endif
+        while (null_pos < null_pos_end) {
+            if (*null_pos != 0) {
+                return true;
+            }
+            null_pos++;
         }
         return false;
     }

be/src/vec/core/sort_cursor.h

@@ -116,7 +116,7 @@ struct ReceiveQueueSortCursorImpl : public SortCursorImpl {
             desc[i].direction = is_asc_order[i] ? 1 : -1;
             desc[i].nulls_direction = nulls_first[i] ? 1 : -1;
         }
-        has_next_block();
+        _is_eof = !has_next_block();
     }
 
     bool has_next_block() override {

be/src/vec/exec/vaggregation_node.h

@@ -47,10 +47,10 @@ struct AggregationMethodSerialized {
 
     Data data;
 
-    AggregationMethodSerialized() {}
+    AggregationMethodSerialized() = default;
 
     template <typename Other>
-    AggregationMethodSerialized(const Other& other) : data(other.data) {}
+    explicit AggregationMethodSerialized(const Other& other) : data(other.data) {}
 
     using State = ColumnsHashing::HashMethodSerialized<typename Data::value_type, Mapped>;
 
@@ -153,6 +153,7 @@ class AggregationNode : public ::doris::ExecNode {
     using vectorized_execute = std::function<Status(Block* block)>;
     using vectorized_get_result =
             std::function<Status(RuntimeState* state, Block* block, bool* eos)>;
+
     struct executor {
         vectorized_execute execute;
         vectorized_get_result get_result;

be/src/vec/exec/vsort_node.cpp

@@ -124,7 +124,7 @@ Status VSortNode::sort_input(RuntimeState* state) {
     do {
         Block block;
         RETURN_IF_ERROR(child(0)->get_next(state, &block, &eos));
-        if (!eos && block.rows() != 0) {
+        if ( block.rows() != 0) {
             RETURN_IF_ERROR(pretreat_block(block));
             _sorted_blocks.emplace_back(std::move(block));
             RETURN_IF_CANCELLED(state);

be/src/vec/exec/vsort_node.h

@@ -28,15 +28,9 @@
 namespace doris {
 
 namespace vectorized {
-// Node that implements a full sort of its input with a fixed memory budget, spilling
-// to disk if the input is larger than available memory.
-// Uses SpillSorter and BufferedBlockMgr for the external sort implementation.
-// Input rows to SortNode are materialized by the SpillSorter into a single tuple
-// using the expressions specified in _sort_exec_exprs.
-// In get_next(), SortNode passes in the output batch to the sorter instance created
-// in open() to fill it with sorted rows.
-// If a merge phase was performed in the sort, sorted rows are deep copied into
-// the output batch. Otherwise, the sorter instance owns the sorted data.
+// Node that implements a full sort of its input with a fixed memory budget
+// In open() the input Block to VSortNode will sort firstly, using the expressions specified in _sort_exec_exprs.
+// In get_next(), VSortNode do the merge sort to gather data to a new block
 
 // support spill to disk in the future
 class VSortNode : public doris::ExecNode {
@@ -75,7 +69,7 @@ class VSortNode : public doris::ExecNode {
     // Number of rows to skip.
     int64_t _offset;
 
-    // Expressions and parameters used for tuple materialization and tuple comparison.
+    // Expressions and parameters used for build _sort_description
     VSortExecExprs _vsort_exec_exprs;
     std::vector<bool> _is_asc_order;
     std::vector<bool> _nulls_first;
@@ -85,11 +79,9 @@ class VSortNode : public doris::ExecNode {
     std::vector<Block> _sorted_blocks;
     std::priority_queue<SortCursor> _priority_queue;
 
+    // TODO: Not using now, maybe should be delete
     // Keeps track of the number of rows skipped for handling _offset.
     int64_t _num_rows_skipped;
-
-    // END: Members that must be reset()
-    /////////////////////////////////////////
 };
 
 }

be/src/vec/runtime/vsorted_run_merger.h

@@ -31,17 +31,12 @@ class RuntimeProfile;
 
 namespace vectorized {
 class Block;
-// VSortedRunMerger is used to merge multiple sorted runs of tuples. A run is a sorted
-// sequence of row batches, which are fetched from a BlockSupplier function object.
+// VSortedRunMerger is used to merge multiple sorted runs of blocks. A run is a sorted
+// sequence of blocks, which are fetched from a BlockSupplier function object.
 // Merging is implemented using a binary min-heap that maintains the run with the next
-// tuple in sorted order at the top of the heap.
+// rows in sorted order at the top of the heap.
 //
-// Merged batches of rows are retrieved from VSortedRunMerger via calls to get_next().
-// The merger is constructed with a boolean flag deep_copy_input.
-// If true, sorted output rows are deep copied into the data pool of the output batch.
-// If false, get_next() only copies tuple pointers (TupleRows) into the output batch,
-// and transfers resource ownership from the input batches to the output batch when
-// an input batch is processed.
+// Merged block of rows are retrieved from VSortedRunMerger via calls to get_next().
 class VSortedRunMerger {
 public:
     // Function that returns the next block of rows from an input sorted run. The batch
@@ -57,10 +52,10 @@ class VSortedRunMerger {
     // the priority queue.
     Status prepare(const std::vector<BlockSupplier>& input_runs, bool parallel = false);
 
-    // Return the next batch of sorted rows from this merger.
+    // Return the next block of sorted rows from this merger.
     Status get_next(Block* output_block, bool *eos);
 
-    // Only Child class implement this Method, Return the next batch of sorted rows from this merger.
+    // Do not support now
     virtual Status get_batch(RowBatch **output_batch) {
         return Status::InternalError("no support method get_batch(RowBatch** output_batch)");
     }
@@ -80,9 +75,6 @@ class VSortedRunMerger {
 
     Block _empty_block;
 
-    // Pool of BatchedRowSupplier instances.
-    ObjectPool _pool;
-
     // Times calls to get_next().
     RuntimeProfile::Counter *_get_next_timer;