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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
