chromium/third_party/eigen3/src/Eigen/src/Core/util/Serializer.h

// This file is part of Eigen, a lightweight C++ template library
// for linear algebra.
//
// Copyright (C) 2021 The Eigen Team
//
// This Source Code Form is subject to the terms of the Mozilla
// Public License v. 2.0. If a copy of the MPL was not distributed
// with this file, You can obtain one at http://mozilla.org/MPL/2.0/.

#ifndef EIGEN_SERIALIZER_H
#define EIGEN_SERIALIZER_H

#include <type_traits>

// The Serializer class encodes data into a memory buffer so it can be later
// reconstructed. This is mainly used to send objects back-and-forth between
// the CPU and GPU.

namespace Eigen {

/**
 * Serializes an object to a memory buffer.
 *
 * Useful for transferring data (e.g. back-and-forth to a device).
 */
template <typename T, typename EnableIf = void>
class Serializer;

// Specialization for POD types.
Serializer<T, typename std::enable_if_t<std::is_trivial<T>::value && std::is_standard_layout<T>::value>>;

// Specialization for DenseBase.
// Serializes [rows, cols, data...].
Serializer<DenseBase<Derived>, void>;

Serializer<Matrix<Scalar, Rows, Cols, Options, MaxRows, MaxCols>>;

Serializer<Array<Scalar, Rows, Cols, Options, MaxRows, MaxCols>>;

namespace internal {

// Recursive serialization implementation helper.
template <size_t N, typename... Types>
struct serialize_impl;

serialize_impl<N, T1, Ts...>;

// Base case.
template <>
struct serialize_impl<0> { … };

}  // namespace internal

/**
 * Determine the buffer size required to serialize a set of values.
 *
 * \param args ... arguments to serialize in sequence.
 * \return the total size of the required buffer.
 */
template <typename... Args>
EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE size_t serialize_size(const Args&... args) { … }

/**
 * Serialize a set of values to the byte buffer.
 *
 * \param dest output byte buffer; if this is nullptr, does nothing.
 * \param end the end of the output byte buffer.
 * \param args ... arguments to serialize in sequence.
 * \return the next address after all serialized values.
 */
template <typename... Args>
EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE uint8_t* serialize(uint8_t* dest, uint8_t* end, const Args&... args) { … }

/**
 * Deserialize a set of values from the byte buffer.
 *
 * \param src input byte buffer; if this is nullptr, does nothing.
 * \param end the end of input byte buffer.
 * \param args ... arguments to deserialize in sequence.
 * \return the next address after all parsed values; nullptr if parsing errors are detected.
 */
template <typename... Args>
EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE const uint8_t* deserialize(const uint8_t* src, const uint8_t* end,
                                                                 Args&... args) { … }

}  // namespace Eigen

#endif  // EIGEN_SERIALIZER_H