chromium/third_party/eigen3/src/unsupported/Eigen/CXX11/src/Tensor/TensorMorphing.h

// This file is part of Eigen, a lightweight C++ template library
// for linear algebra.
//
// Copyright (C) 2014 Benoit Steiner <[email protected]>
//
// 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_CXX11_TENSOR_TENSOR_MORPHING_H
#define EIGEN_CXX11_TENSOR_TENSOR_MORPHING_H

// IWYU pragma: private
#include "./InternalHeaderCheck.h"

namespace Eigen {

/** \class TensorReshaping
 * \ingroup CXX11_Tensor_Module
 *
 * \brief Tensor reshaping class.
 *
 *
 */
namespace internal {
traits<TensorReshapingOp<NewDimensions, XprType>>;

eval<TensorReshapingOp<NewDimensions, XprType>, Eigen::Dense>;

nested<TensorReshapingOp<NewDimensions, XprType>, 1, typename eval<TensorReshapingOp<NewDimensions, XprType>>::type>;

}  // end namespace internal

template <typename NewDimensions, typename XprType>
class TensorReshapingOp : public TensorBase<TensorReshapingOp<NewDimensions, XprType>, WriteAccessors> { … };

// Eval as rvalue
TensorEvaluator<const TensorReshapingOp<NewDimensions, ArgType>, Device>;

// Eval as lvalue
TensorEvaluator<TensorReshapingOp<NewDimensions, ArgType>, Device>;

/** \class TensorSlicing
 * \ingroup CXX11_Tensor_Module
 *
 * \brief Tensor slicing class.
 *
 *
 */
namespace internal {
traits<TensorSlicingOp<StartIndices, Sizes, XprType>>;

eval<TensorSlicingOp<StartIndices, Sizes, XprType>, Eigen::Dense>;

nested<TensorSlicingOp<StartIndices, Sizes, XprType>, 1, typename eval<TensorSlicingOp<StartIndices, Sizes, XprType>>::type>;

}  // end namespace internal

template <typename StartIndices, typename Sizes, typename XprType>
class TensorSlicingOp : public TensorBase<TensorSlicingOp<StartIndices, Sizes, XprType>> { … };

namespace internal {

// Fixme: figure out the exact threshold
template <typename Index, typename Device, bool BlockAccess>
struct MemcpyTriggerForSlicing { … };

// It is very expensive to start the memcpy kernel on GPU: we therefore only
// use it for large copies.
#ifdef EIGEN_USE_GPU
template <typename Index, bool BlockAccess>
struct MemcpyTriggerForSlicing<Index, GpuDevice, BlockAccess> {
  EIGEN_DEVICE_FUNC MemcpyTriggerForSlicing(const GpuDevice&) {}
  EIGEN_DEVICE_FUNC bool operator()(Index, Index contiguous) const { return contiguous > 4 * 1024 * 1024; }
};
#endif

// It is very expensive to start the memcpy kernel on GPU: we therefore only
// use it for large copies.
#ifdef EIGEN_USE_SYCL
template <typename Index, bool BlockAccess>
struct MemcpyTriggerForSlicing<Index, Eigen::SyclDevice, BlockAccess> {
  EIGEN_DEVICE_FUNC MemcpyTriggerForSlicing(const SyclDevice&) {}
  EIGEN_DEVICE_FUNC bool operator()(Index, Index contiguous) const { return contiguous > 4 * 1024 * 1024; }
};
#endif

}  // namespace internal

// Eval as rvalue
TensorEvaluator<const TensorSlicingOp<StartIndices, Sizes, ArgType>, Device>;

// Eval as lvalue
TensorEvaluator<TensorSlicingOp<StartIndices, Sizes, ArgType>, Device>;

namespace internal {
traits<TensorStridingSlicingOp<StartIndices, StopIndices, Strides, XprType>>;

eval<TensorStridingSlicingOp<StartIndices, StopIndices, Strides, XprType>, Eigen::Dense>;

nested<TensorStridingSlicingOp<StartIndices, StopIndices, Strides, XprType>, 1, typename eval<TensorStridingSlicingOp<StartIndices, StopIndices, Strides, XprType>>::type>;

}  // end namespace internal

template <typename StartIndices, typename StopIndices, typename Strides, typename XprType>
class TensorStridingSlicingOp
    : public TensorBase<TensorStridingSlicingOp<StartIndices, StopIndices, Strides, XprType>> { … };

// Eval as rvalue
TensorEvaluator<const TensorStridingSlicingOp<StartIndices, StopIndices, Strides, ArgType>, Device>;

// Eval as lvalue
TensorEvaluator<TensorStridingSlicingOp<StartIndices, StopIndices, Strides, ArgType>, Device>;

}  // end namespace Eigen

#endif  // EIGEN_CXX11_TENSOR_TENSOR_MORPHING_H