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/*! \file
    \brief Scheduler for grouped GEMM
*/

#pragma once

#include "cutlass/cutlass.h"
#include "cutlass/gemm/gemm.h"
#include "cutlass/matrix_coord.h"
#include "cutlass/gemm/kernel/grouped_problem_visitor.h"

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

namespace cutlass {
namespace gemm {
namespace kernel {

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

namespace detail {
// Helper for correctly representing problem sizes in grouped kernels 
template <
  typename ThreadblockShape,
  bool Transposed
>
struct GemmGroupedProblemSizeHelper {

  static bool const kTransposed = Transposed;

  CUTLASS_HOST_DEVICE
  static cutlass::gemm::GemmCoord grid_shape(const cutlass::gemm::GemmCoord& problem) {
    return cutlass::gemm::GemmCoord(
      ((problem.m() - 1 + ThreadblockShape::kM) / ThreadblockShape::kM),
      ((problem.n() - 1 + ThreadblockShape::kN) / ThreadblockShape::kN),
      1);
  }

  CUTLASS_HOST_DEVICE
  static void possibly_transpose_problem(cutlass::gemm::GemmCoord& problem) {
    if (kTransposed) {
      swap(problem.m(), problem.n());
    }
  }

  CUTLASS_HOST_DEVICE
  static int32_t tile_count(const cutlass::gemm::GemmCoord& grid) {
    return grid.m() * grid.n();
  }
};

} // namespace detail

/// Visitor class to abstract away the algorithm for iterating over tiles
template <typename ThreadblockShape,
          GroupScheduleMode GroupScheduleMode_,
          int PrefetchTileCount,
          int ThreadCount,
          bool Transposed = false>
struct GemmGroupedProblemVisitor : public GroupedProblemVisitor<
                                            detail::GemmGroupedProblemSizeHelper<ThreadblockShape, Transposed>,
                                            ThreadblockShape,
                                            GroupScheduleMode_,
                                            PrefetchTileCount,
                                            ThreadCount> {

  static bool const kTransposed = Transposed;

  using ProblemSizeHelper = detail::GemmGroupedProblemSizeHelper<ThreadblockShape, Transposed>;
  using Base = GroupedProblemVisitor<ProblemSizeHelper, ThreadblockShape, GroupScheduleMode_, PrefetchTileCount, ThreadCount>;
  using Params = typename Base::Params;
  using SharedStorage = typename Base::SharedStorage;

  //
  // Methods
  //
  CUTLASS_DEVICE
  GemmGroupedProblemVisitor(
    Params const &params_,
    SharedStorage &shared_storage_, 
    int32_t block_idx
  ): Base (params_, shared_storage_, block_idx)
  {}
};

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

} // namespace kernel
} // namespace gemm
} // namespace cutlass

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