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/*! \file
    \brief Defines a type for restructuring a tile.
*/
#pragma once

#include <cutlass/shape.h>

namespace cutlass {

////////////////////////////////////////////////////////////////////////////////////////////////////

// The following functor reshapes a tile of data. The goal is to have at least kAccessSize in
// the inner-most dimension. If the user respects that constraint, there is nothing to be done. If
// that's not the case, this functor will correct that and "extract" the right number of elements
// from the next dimension.

template <typename Tile_, int kAccessSize_, bool = (Tile_::kC < kAccessSize_)>
struct ReshapeTile {
  typedef Tile_ Tile;
};

template <typename Tile_, int kAccessSize_>
struct ReshapeTile<Tile_, kAccessSize_, true> {
  // Make sure the W dimension of the tile is large enough.
  static_assert(Tile_::kW >= kAccessSize_, "The W dimension is too small");
  // Make sure the dimension can be divided by the number of scalars.
  static_assert(Tile_::kW % kAccessSize_ == 0, "Not supported");
  // Collapse the W dimension.
  typedef Shape<Tile_::kD, Tile_::kH, Tile_::kW / kAccessSize_, kAccessSize_> Tile;
};

////////////////////////////////////////////////////////////////////////////////////////////////////

}  // namespace cutlass