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/*! \file
    \brief Defines basic structures needed for implementing the warp-scoped phase of the epilogue.
          These quantities assume a 'column-major' arrangement of TensorOp instructions, of which
          a row-oriented slice is visible per iteration.
*/

#pragma once

#include "cutlass/arch/wmma.h"
#include "cutlass/matrix_shape.h"
#include "cutlass/layout/matrix.h"

#if defined(CUTLASS_ARCH_WMMA_ENABLED)

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

namespace cutlass {
namespace epilogue {
namespace warp {

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

/// Policy details related to the epilogue
template <
  typename WarpShape,     ///< shape of warp-level GEMM (concept: MatrixShape)
  typename OperatorShape, ///< matrix multiply operation shape (concept: gemm:GemmShape)
  typename Layout         ///< target shared memory layout
>
struct WmmaTensorOpPolicy; 

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

/// Partial specialization for row-major
template <
  typename WarpShape,           ///< shape of warp-level GEMM (concept: MatrixShape)
  typename OperatorShape        ///< matrix multiply operation shape (concept: gemm::GemmShape)
>
struct WmmaTensorOpPolicy<WarpShape, OperatorShape, layout::RowMajor> {

  /// Number of operations
  using OperatorCount = MatrixShape<
    WarpShape::kM / OperatorShape::kM,
    WarpShape::kN / OperatorShape::kN
  >;

  //
  // Hard-coded constants regarding Tensor Operations
  //
  static int const kElementsPerAccess = 2;
  static int const kRowsPerIteration = OperatorShape::kM;
  static int const kWmmaFragmentsPerAccess = 1;

  //
  // Derived quantities
  //

  // Number of externally visible iterations
  static int const kIterations = OperatorCount::kRow;

};

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

} // namespace warp
} // namespace epilogue
} // namespace cutlass

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

#endif

