be/src/vec/common/pod_array_fwd.h

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// to you under the Apache License, Version 2.0 (the
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//
//   http://www.apache.org/licenses/LICENSE-2.0
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// This file is copied from
// https://github.com/ClickHouse/ClickHouse/blob/master/src/Common/PODArray_fwd.h
// and modified by Doris

/**
  * This file contains some using-declarations that define various kinds of
  * PODArray.
  */
#pragma once

#include "vec/common/allocator_fwd.h"

namespace doris::vectorized {

inline constexpr size_t integerRoundUp(size_t value, size_t dividend) {
    return ((value + dividend - 1) / dividend) * dividend;
}

template <typename T, size_t initial_bytes = 4096, typename TAllocator = Allocator<false>,
          size_t pad_right_ = 0, size_t pad_left_ = 0>
class PODArray;

/** For columns. Padding is enough to read and write xmm-register at the address of the last element. 
  * TODO, pad_right is temporarily changed from 15 to 16, will waste 1 bytes,
  * can rollback after fix wrong reinterpret_cast column and PODArray swap.
  */
template <typename T, size_t initial_bytes = 4096, typename TAllocator = Allocator<false>>
using PaddedPODArray = PODArray<T, initial_bytes, TAllocator, 16, 16>;

/** A helper for declaring PODArray that uses inline memory.
  * The initial size is set to use all the inline bytes, since using less would
  * only add some extra allocation calls.
  */
template <typename T, size_t inline_bytes,
          size_t rounded_bytes = integerRoundUp(inline_bytes, sizeof(T))>
using PODArrayWithStackMemory =
        PODArray<T, rounded_bytes,
                 AllocatorWithStackMemory<Allocator<false>, rounded_bytes, alignof(T)>>;

} // namespace doris::vectorized