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#pragma once

#include "hytlass/hytlass.h"
#include "hytlass/gemm/dispatch_policy.hpp"

#include "hute/algorithm/functional.hpp"
#include "hute/atom/mma_atom.hpp"
#include "hute/algorithm/gemm.hpp"
#include "hute/atom/mma_atom.hpp"
#include "hute/tensor_predicate.hpp"


/////////////////////////////////////////////////////////////////////////////////////////////////
 
namespace hytlass::gemm::collective {
using namespace hute;

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

template <
  class TileShape_,
  class ElementA_,
  class StrideA_,
  class ElementB_,
  class StrideB_,
  class TiledMma_,
  class GmemTiledCopyA_,
  class SmemLayoutAtomA_,
  class SmemCopyAtomA_,
  class TransformA_,
  class GmemTiledCopyB_,
  class SmemLayoutAtomB_,
  class SmemCopyAtomB_,
  class TransformB_>
struct CollectiveMma<
    MainloopGfx928TwoStageUnpredicated,
    TileShape_,
    ElementA_,
    StrideA_,
    ElementB_,
    StrideB_,
    TiledMma_,
    GmemTiledCopyA_,
    SmemLayoutAtomA_,
    SmemCopyAtomA_,
    TransformA_,
    GmemTiledCopyB_,
    SmemLayoutAtomB_,
    SmemCopyAtomB_,
    TransformB_>
{
  //
  // Type Aliases
  //
  using DispatchPolicy = MainloopGfx928TwoStageUnpredicated;
  using TileShape = TileShape_;
  using ElementA = ElementA_;
  using StrideA = StrideA_;
  using ElementB = ElementB_;
  using StrideB = StrideB_;
  using TiledMma = TiledMma_;
  using ElementAccumulator = typename TiledMma::ValTypeC;
  using GmemTiledCopyA = GmemTiledCopyA_;
  using GmemTiledCopyB = GmemTiledCopyB_;
  using SmemLayoutAtomA = SmemLayoutAtomA_;
  using SmemLayoutAtomB = SmemLayoutAtomB_;
  using SmemCopyAtomA = SmemCopyAtomA_;
  using SmemCopyAtomB = SmemCopyAtomB_;
  using TransformA = TransformA_;
  using TransformB = TransformB_;
  using ArchTag = typename DispatchPolicy::ArchTag;

  static_assert(hute::rank(SmemLayoutAtomA{}) == 2, "SmemLayoutAtom must be rank 2 (M/N, K)");
  static_assert((size<0>(TileShape{}) % size<0>(SmemLayoutAtomA{})) == 0, "SmemLayoutAtom must evenly divide tile shape.");
  static_assert((size<2>(TileShape{}) % size<1>(SmemLayoutAtomA{})) == 0, "SmemLayoutAtom must evenly divide tile shape.");

  static_assert(hute::rank(SmemLayoutAtomB{}) == 2, "SmemLayoutAtom must be rank 2 (M/N, K)");
  static_assert((size<1>(TileShape{}) % size<0>(SmemLayoutAtomB{})) == 0, "SmemLayoutAtom must evenly divide tile shape.");
  static_assert((size<2>(TileShape{}) % size<1>(SmemLayoutAtomB{})) == 0, "SmemLayoutAtom must evenly divide tile shape.");

  using SmemLayoutA = decltype(tile_to_shape(
      SmemLayoutAtomA{},
      make_shape(shape<0>(TileShape{}), shape<2>(TileShape{}))));
  using SmemLayoutB = decltype(tile_to_shape(
      SmemLayoutAtomB{},
      make_shape(shape<1>(TileShape{}), shape<2>(TileShape{}))));

  struct SharedStorage
  {
    hute::array_aligned<ElementA, hute::cosize_v<SmemLayoutA>> smem_a;
    hute::array_aligned<ElementB, hute::cosize_v<SmemLayoutB>> smem_b;
  };

  // Host side kernel arguments
  struct Arguments {
    ElementA const* ptr_A;
    StrideA dA;
    ElementB const* ptr_B;
    StrideB dB;
  };

  // Device side kernel params
  using Params = Arguments;

  //
  // Methods
  //

  CollectiveMma() = default;

  template <class ProblemShape>
  static constexpr Params
  to_underlying_arguments(ProblemShape const& _, Arguments const& args, void* workspace) {
    (void) workspace;
    return args;
  }

  /// Perform a threadblock-scoped matrix multiply-accumulate
  template <
    class FrgTensorD,
    class TensorA,
    class TensorB,
    class FrgTensorC,
    class KTileIterator,
    class ResidueMNK
  >
  HYTLASS_DEVICE void
  operator() (
      FrgTensorD &accum,
      TensorA gA,
      TensorB gB,
      FrgTensorC const &src_accum,
      KTileIterator k_tile_iter, int k_tile_count,
      ResidueMNK residue_mnk,
      int thread_idx,
      char *smem_buf) 
  {
    using namespace hute;

    (void)residue_mnk;

    static_assert(is_rmem<FrgTensorD>::value, "D tensor must be rmem resident.");
    static_assert(is_gmem<TensorA>::value, "A tensor must be gmem resident.");
    static_assert(is_gmem<TensorB>::value, "B tensor must be gmem resident.");
    static_assert(is_rmem<FrgTensorC>::value, "C tensor must be rmem resident.");
    static_assert(hute::rank(SmemLayoutA{}) == 2,
      "MainloopTwoStage must not have a smem shape with a pipeline mode.");
    static_assert(hute::rank(SmemLayoutB{}) == 2,
      "MainloopTwoStage must not have a smem shape with a pipeline mode.");

    // Construct shared memory tiles
    SharedStorage& storage = *reinterpret_cast<SharedStorage*>(smem_buf);
    Tensor sA = make_tensor(make_smem_ptr(storage.smem_a.data()), SmemLayoutA{}); // (BLK_M,BLK_K,PIPE)
    Tensor sB = make_tensor(make_smem_ptr(storage.smem_b.data()), SmemLayoutB{}); // (BLK_N,BLK_K,PIPE)

    // Partition the copying of A and B tiles across the threads
    GmemTiledCopyA gmem_tiled_copy_a;
    GmemTiledCopyB gmem_tiled_copy_b;
    auto copy_a_thr = gmem_tiled_copy_a.get_slice(thread_idx);
    auto copy_b_thr = gmem_tiled_copy_b.get_slice(thread_idx);

    Tensor tAgA = copy_a_thr.partition_S(gA);                                  // (ACPY,ACPY_M,ACPY_K,k)
    Tensor tAsA = copy_a_thr.partition_D(sA);                                  // (ACPY,ACPY_M,ACPY_K)
    Tensor tBgB = copy_b_thr.partition_S(gB);                                  // (BCPY,BCPY_N,BCPY_K,k)
    Tensor tBsB = copy_b_thr.partition_D(sB);                                  // (BCPY,BCPY_N,BCPY_K)

    // Allocate the register tiles for double buffering -- same shape as partitioned data
    Tensor tArA = make_fragment_like(tAsA);                                    // (ACPY,ACPY_M,ACPY_K)
    Tensor tBrB = make_fragment_like(tBsB);                                    // (BCPY,BCPY_N,BCPY_K)

    // Tile MMA compute thread partitions and allocate accumulators
    TiledMma tiled_mma;
    auto thr_mma = tiled_mma.get_thread_slice(thread_idx);
    Tensor tCrA  = thr_mma.partition_fragment_A(sA);                           // (MMA,MMA_M,MMA_K)
    Tensor tCrB  = thr_mma.partition_fragment_B(sB);                           // (MMA,MMA_M,MMA_K)

    HUTE_STATIC_ASSERT_V(size<1>(tCrA) == size<1>(accum));                     // MMA_M
    HUTE_STATIC_ASSERT_V(size<1>(tCrA) == size<1>(src_accum));                 // MMA_M
    HUTE_STATIC_ASSERT_V(size<1>(tCrB) == size<2>(accum));                     // MMA_N
    HUTE_STATIC_ASSERT_V(size<1>(tCrB) == size<2>(src_accum));                 // MMA_N
    HUTE_STATIC_ASSERT_V(size<2>(tCrA) == size<2>(tCrB));                      // MMA_K

    //
    // Copy Atom retiling
    //

    auto thr_copy_A       = make_tiled_copy_A(SmemCopyAtomA{}, tiled_mma).get_thread_slice(thread_idx);
    auto s2r_tiled_copy_a = make_tiled_copy_A(SmemCopyAtomA{}, tiled_mma);
    Tensor tCsA           = thr_copy_A.partition_S(sA);
    Tensor tCrA_copy_view = thr_copy_A.retile_D(tCrA);
    HUTE_STATIC_ASSERT_V(size<1>(tCsA) == size<1>(tCrA_copy_view));            // M

    auto thr_copy_B       = make_tiled_copy_B(SmemCopyAtomB{}, tiled_mma).get_thread_slice(thread_idx);
    auto s2r_tiled_copy_b = make_tiled_copy_B(SmemCopyAtomB{}, tiled_mma);
    Tensor tCsB           = thr_copy_B.partition_S(sB);
    Tensor tCrB_copy_view = thr_copy_B.retile_D(tCrB);
    HUTE_STATIC_ASSERT_V(size<1>(tCsB) == size<1>(tCrB_copy_view));            // N

    //
    // Prologue
    //

    // Copy gmem to rmem for the first k_tile
    copy(gmem_tiled_copy_a, tAgA(_,_,_,*k_tile_iter), tArA);
    copy(gmem_tiled_copy_b, tBgB(_,_,_,*k_tile_iter), tBrB);
    if (--k_tile_count > 0) ++k_tile_iter;
    // Copy rmem to smem
    copy(tArA, tAsA);
    copy(tBrB, tBsB);
    // Clear accumulators
    __syncthreads();

    // Load A, B smem->rmem for k=0

    // copy(tCsA(_,_,0), tCrA_copy_view(_,_,0));
    // copy(tCsB(_,_,0), tCrB_copy_view(_,_,0));

    copy(s2r_tiled_copy_a,tCsA(_,_,0), tCrA_copy_view(_,_,0));
    copy(s2r_tiled_copy_b,tCsB(_,_,0), tCrB_copy_view(_,_,0));
    //
    // Mainloop
    //

    // Size of the k-tiles's outer product mode (k)
    auto K_BLOCK_MAX = size<2>(tCrA);

    HYTLASS_PRAGMA_NO_UNROLL
    while (k_tile_count > -1)
    {
      // Pipeline the outer products with a static for loop
      for_each(make_int_sequence<K_BLOCK_MAX>{}, [&] (auto k_block) 
      {
        if (k_block == K_BLOCK_MAX - 1) 
        {
          __syncthreads();

          // Copy rmem to smem
          copy(tArA, tAsA);
          copy(tBrB, tBsB);
          __syncthreads();
        }

        // Load A, B smem->rmem for k+1
        int k_block_next = (k_block + Int<1>{}) % K_BLOCK_MAX;     // static
    
        // copy(tCsA(_,_,k_block_next), tCrA_copy_view(_,_,k_block_next));
        // copy(tCsB(_,_,k_block_next), tCrB_copy_view(_,_,k_block_next)); 
 
        copy(s2r_tiled_copy_a,tCsA(_,_,k_block_next), tCrA_copy_view(_,_,k_block_next));
        copy(s2r_tiled_copy_b,tCsB(_,_,k_block_next), tCrB_copy_view(_,_,k_block_next));

        if (k_block == 0) 
        {
          // Copy gmem to rmem
          copy(gmem_tiled_copy_a, tAgA(_,_,_,*k_tile_iter), tArA);
          copy(gmem_tiled_copy_b, tBgB(_,_,_,*k_tile_iter), tBrB);
          if (--k_tile_count > 0) ++k_tile_iter;
        }

        // transform before compute
        hute::transform(tCrA(_,_,k_block), TransformA{});
        hute::transform(tCrB(_,_,k_block), TransformB{});

        // Thread-level register gemm for k
        // disambiguate gemm (shared with the namespace name)
        hute::gemm(tiled_mma, accum, tCrA(_,_,k_block), tCrB(_,_,k_block), src_accum);
      });
    }
  }
};

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

template <
  class ClusterShape_,
  class ArchTag_,
  class KernelSchedule_,
  class TileShape_,
  class ElementA_,
  class StrideA_,
  class ElementB_,
  class StrideB_,
  class TiledMma_,
  class GmemTiledCopyA_,
  class SmemLayoutAtomA_,
  class SmemCopyAtomA_,
  class TransformA_,
  class GmemTiledCopyB_,
  class SmemLayoutAtomB_,
  class SmemCopyAtomB_,
  class TransformB_>
struct CollectiveMma<
    MainloopDispatch<2, ArchTag_, ClusterShape_, KernelSchedule_>,
    TileShape_,
    ElementA_,
    StrideA_,
    ElementB_,
    StrideB_,
    TiledMma_,
    GmemTiledCopyA_,
    SmemLayoutAtomA_,
    SmemCopyAtomA_,
    TransformA_,
    GmemTiledCopyB_,
    SmemLayoutAtomB_,
    SmemCopyAtomB_,
    TransformB_>
{
  //
  // Type Aliases
  //
  using DispatchPolicy = MainloopDispatch<2, ArchTag_, ClusterShape_, KernelSchedule_>;
  using TileShape = TileShape_;
  using ElementA = ElementA_;
  using StrideA = StrideA_;
  using ElementB = ElementB_;
  using StrideB = StrideB_;
  using TiledMma = TiledMma_;
  using ElementAccumulator = typename TiledMma::ValTypeC;
  using GmemTiledCopyA = GmemTiledCopyA_;
  using GmemTiledCopyB = GmemTiledCopyB_;
  using SmemLayoutAtomA = SmemLayoutAtomA_;
  using SmemLayoutAtomB = SmemLayoutAtomB_;
  using SmemCopyAtomA = SmemCopyAtomA_;
  using SmemCopyAtomB = SmemCopyAtomB_;
  using TransformA = TransformA_;
  using TransformB = TransformB_;
  using ArchTag = typename DispatchPolicy::ArchTag;

  static_assert(hute::rank(SmemLayoutAtomA{}) == 2, "SmemLayoutAtom must be rank 2 (M/N, K)");
  static_assert((size<0>(TileShape{}) % size<0>(SmemLayoutAtomA{})) == 0, "SmemLayoutAtom must evenly divide tile shape.");
  static_assert((size<2>(TileShape{}) % size<1>(SmemLayoutAtomA{})) == 0, "SmemLayoutAtom must evenly divide tile shape.");

  static_assert(hute::rank(SmemLayoutAtomB{}) == 2, "SmemLayoutAtom must be rank 2 (M/N, K)");
  static_assert((size<1>(TileShape{}) % size<0>(SmemLayoutAtomB{})) == 0, "SmemLayoutAtom must evenly divide tile shape.");
  static_assert((size<2>(TileShape{}) % size<1>(SmemLayoutAtomB{})) == 0, "SmemLayoutAtom must evenly divide tile shape.");

  using SmemLayoutA = decltype(tile_to_shape(
      SmemLayoutAtomA{},
      make_shape(shape<0>(TileShape{}), shape<2>(TileShape{}))));
  using SmemLayoutB = decltype(tile_to_shape(
      SmemLayoutAtomB{},
      make_shape(shape<1>(TileShape{}), shape<2>(TileShape{}))));

  struct SharedStorage
  {
    hute::array_aligned<ElementA, hute::cosize_v<SmemLayoutA>> smem_a;
    hute::array_aligned<ElementB, hute::cosize_v<SmemLayoutB>> smem_b;
  };

  // Host side kernel arguments
  struct Arguments {
    ElementA const* ptr_A;
    StrideA dA;
    ElementB const* ptr_B;
    StrideB dB;
  };

  // Device side kernel params
  using Params = Arguments;

  //
  // Methods
  //

  CollectiveMma() = default;

  template <class ProblemShape>
  static constexpr Params
  to_underlying_arguments(ProblemShape const& _, Arguments const& args, void* workspace) {
    (void) workspace;
    return args;
  }

  /// Perform a threadblock-scoped matrix multiply-accumulate
  template <
    class FrgTensorD,
    class TensorA,
    class TensorB,
    class FrgTensorC,
    class KTileIterator,
    class ResidueMNK
  >
  HYTLASS_DEVICE void
  operator() (
      FrgTensorD &accum,
      TensorA gA,
      TensorB gB,
      FrgTensorC const &src_accum,
      KTileIterator k_tile_iter, int k_tile_count,
      ResidueMNK residue_mnk,
      int thread_idx,
      char *smem_buf) 
  {
    using namespace hute;

    static_assert(is_rmem<FrgTensorD>::value, "D tensor must be rmem resident.");
    static_assert(is_gmem<TensorA>::value, "A tensor must be gmem resident.");
    static_assert(is_gmem<TensorB>::value, "B tensor must be gmem resident.");
    static_assert(is_rmem<FrgTensorC>::value, "C tensor must be rmem resident.");
    static_assert(hute::rank(SmemLayoutA{}) == 2,
      "MainloopTwoStage must not have a smem shape with a pipeline mode.");
    static_assert(hute::rank(SmemLayoutB{}) == 2,
      "MainloopTwoStage must not have a smem shape with a pipeline mode.");

    // Construct shared memory tiles
    SharedStorage& storage = *reinterpret_cast<SharedStorage*>(smem_buf);
    Tensor sA = make_tensor(make_smem_ptr(storage.smem_a.data()), SmemLayoutA{}); // (BLK_M,BLK_K,PIPE)
    Tensor sB = make_tensor(make_smem_ptr(storage.smem_b.data()), SmemLayoutB{}); // (BLK_N,BLK_K,PIPE)

    // Shift tensor so residue_k is at origin (Can't read any k_coord < residue_k)
    // This aligns the tensor with BLK_K for all but the 0th k_tile
    gA.data() = &gA(0, get<2>(residue_mnk), 0);
    gB.data() = &gB(0, get<2>(residue_mnk), 0);

    // Partition the copying of A and B tiles across the threads
    GmemTiledCopyA gmem_tiled_copy_a;
    GmemTiledCopyB gmem_tiled_copy_b;
    auto gmem_thr_copy_a = gmem_tiled_copy_a.get_slice(thread_idx);
    auto gmem_thr_copy_b = gmem_tiled_copy_b.get_slice(thread_idx);

    Tensor tAgA = gmem_thr_copy_a.partition_S(gA);                             // (ACPY,ACPY_M,ACPY_K,k)
    Tensor tAsA = gmem_thr_copy_a.partition_D(sA);                             // (ACPY,ACPY_M,ACPY_K,PIPE)
    Tensor tBgB = gmem_thr_copy_b.partition_S(gB);                             // (BCPY,BCPY_N,BCPY_K,k)
    Tensor tBsB = gmem_thr_copy_b.partition_D(sB);                             // (BCPY,BCPY_N,BCPY_K,PIPE)

    // Allocate the register tiles for double buffering -- same shape as partitioned data
    Tensor tArA = make_fragment_like(tAsA);                                    // (ACPY,ACPY_M,ACPY_K)
    Tensor tBrB = make_fragment_like(tBsB);                                    // (BCPY,BCPY_N,BCPY_K)

    //
    // PREDICATES
    //

    // Allocate predicate tensors for m and n
    Tensor tApA = make_tensor<bool>(make_shape(size<1>(tAsA), size<2>(tAsA)), Stride<_1,_0>{});
    Tensor tBpB = make_tensor<bool>(make_shape(size<1>(tBsB), size<2>(tBsB)), Stride<_1,_0>{});

    // Construct identity layout for sA and sB
    Tensor cA = make_identity_tensor(make_shape(size<0>(sA), size<1>(sA)));    // (BLK_M,BLK_K) -> (blk_m,blk_k)
    Tensor cB = make_identity_tensor(make_shape(size<0>(sB), size<1>(sB)));    // (BLK_N,BLK_K) -> (blk_n,blk_k)

    // Repeat the partitioning with identity layouts
    Tensor tAcA = gmem_thr_copy_a.partition_S(cA);                             // (ACPY,ACPY_M,ACPY_K) -> (blk_m,blk_k)
    Tensor tBcB = gmem_thr_copy_b.partition_S(cB);                             // (BCPY,BCPY_N,BCPY_K) -> (blk_n,blk_k)

    // Set predicates for m bounds
    HYTLASS_PRAGMA_UNROLL
    for (int m = 0; m < size<0>(tApA); ++m) {
      tApA(m,0) = get<0>(tAcA(0,m,0)) < get<0>(residue_mnk);  // blk_m coord < residue_m
    }
    // Set predicates for n bounds
    HYTLASS_PRAGMA_UNROLL
    for (int n = 0; n < size<0>(tBpB); ++n) {
      tBpB(n,0) = get<0>(tBcB(0,n,0)) < get<1>(residue_mnk);  // blk_n coord < residue_n
    }

    //
    // PREFETCH
    //

    // Clear the rmem tiles to account for predicated off loads
    clear(tArA);
    clear(tBrB);

    // Start async loads for 0th k-tile, where we take care of the k residue
    {
      Tensor tAgAk = tAgA(_,_,_,*k_tile_iter);
      HYTLASS_PRAGMA_UNROLL
      for (int k = 0; k < size<2>(tArA); ++k) {
        if (get<1>(tAcA(0,0,k)) >= -get<2>(residue_mnk)) {      // blk_k coord < residue_k (gA shifted)
          copy_if(gmem_tiled_copy_a, tApA(_,k), tAgAk(_,_,k), tArA(_,_,k));
        }
      }
      Tensor tBgBk = tBgB(_,_,_,*k_tile_iter);
      HYTLASS_PRAGMA_UNROLL
      for (int k = 0; k < size<2>(tBrB); ++k) {
        if (get<1>(tBcB(0,0,k)) >= -get<2>(residue_mnk)) {      // blk_k coord < residue_k (gB shifted)
          copy_if(gmem_tiled_copy_b, tBpB(_,k), tBgBk(_,_,k), tBrB(_,_,k));
        }
      }
      ++k_tile_iter;
      --k_tile_count;
    }

    // Tile MMA compute thread partitions and allocate accumulators
    TiledMma tiled_mma;
    auto thr_mma = tiled_mma.get_thread_slice(thread_idx);
    Tensor tCrA  = thr_mma.make_fragment_A(thr_mma.partition_A(sA));           // (MMA,MMA_M,MMA_K)
    Tensor tCrB  = thr_mma.make_fragment_B(thr_mma.partition_B(sB));           // (MMA,MMA_M,MMA_K)

    HUTE_STATIC_ASSERT_V(size<1>(tCrA) == size<1>(accum));                     // MMA_M
    HUTE_STATIC_ASSERT_V(size<1>(tCrA) == size<1>(src_accum));                 // MMA_M
    HUTE_STATIC_ASSERT_V(size<1>(tCrB) == size<2>(accum));                     // MMA_N
    HUTE_STATIC_ASSERT_V(size<1>(tCrB) == size<2>(src_accum));                 // MMA_N
    HUTE_STATIC_ASSERT_V(size<2>(tCrA) == size<2>(tCrB));                      // MMA_K

    //
    // Copy Atom retiling
    //

    auto thr_copy_A       = make_tiled_copy_A(SmemCopyAtomA{}, tiled_mma).get_thread_slice(thread_idx);
    auto s2r_tiled_copy_a = make_tiled_copy_A(SmemCopyAtomA{}, tiled_mma);
    Tensor tCsA           = thr_copy_A.partition_S(sA);
    Tensor tCrA_copy_view = thr_copy_A.retile_D(tCrA);
    HUTE_STATIC_ASSERT_V(size<1>(tCsA) == size<1>(tCrA_copy_view));            // M

    auto thr_copy_B       = make_tiled_copy_B(SmemCopyAtomB{}, tiled_mma).get_thread_slice(thread_idx);
    auto s2r_tiled_copy_b = make_tiled_copy_B(SmemCopyAtomB{}, tiled_mma);
    Tensor tCsB           = thr_copy_B.partition_S(sB);
    Tensor tCrB_copy_view = thr_copy_B.retile_D(tCrB);
    HUTE_STATIC_ASSERT_V(size<1>(tCsB) == size<1>(tCrB_copy_view));            // N

    //
    // Prologue
    //

    // Copy rmem to smem
    copy(tArA, tAsA);
    copy(tBrB, tBsB);
    // Clear accumulators
    __syncthreads();

    // Load A, B smem->rmem for k=0
    copy(s2r_tiled_copy_a,tCsA(_,_,0), tCrA_copy_view(_,_,0));
    copy(s2r_tiled_copy_b,tCsB(_,_,0), tCrB_copy_view(_,_,0));

    //
    // Mainloop
    //

    // Size of the k-tiles's outer product mode (k)
    auto K_BLOCK_MAX = size<2>(tCrA);

    HYTLASS_PRAGMA_NO_UNROLL
    while (k_tile_count > -1)
    {
      // Pipeline the outer products with a static for loop
      for_each(make_int_sequence<K_BLOCK_MAX>{}, [&] (auto k_block) 
      {
        if (k_block == K_BLOCK_MAX - 1) 
        {
          __syncthreads();

          // Copy rmem to smem
          copy(tArA, tAsA);
          copy(tBrB, tBsB);
          __syncthreads();
        }

        // Load A, B smem->rmem for k+1
        int k_block_next = (k_block + Int<1>{}) % K_BLOCK_MAX;    // static
    
        copy(s2r_tiled_copy_a,tCsA(_,_,k_block_next), tCrA_copy_view(_,_,k_block_next));
        copy(s2r_tiled_copy_b,tCsB(_,_,k_block_next), tCrB_copy_view(_,_,k_block_next));

        if (k_block == 0) {

          if (k_tile_count <= 0) {
            clear(tApA);
            clear(tBpB);
          }
          copy_if(gmem_tiled_copy_a, tApA, tAgA(_,_,_,*k_tile_iter), tArA);
          copy_if(gmem_tiled_copy_b, tBpB, tBgB(_,_,_,*k_tile_iter), tBrB);
          ++k_tile_iter;
          --k_tile_count;
        }

        // transform before compute
        hute::transform(tCrA(_,_,k_block), TransformA{});
        hute::transform(tCrB(_,_,k_block), TransformB{});

        // Thread-level register gemm for k
        // disambiguate gemm (shared with the namespace name)
        hute::gemm(tiled_mma, accum, tCrA(_,_,k_block), tCrB(_,_,k_block), src_accum);
      });
    }
  }
};

/////////////////////////////////////////////////////////////////////////////////////////////////
template <
  class ClusterShape_,
  class ArchTag_,
  class KernelSchedule_,
  class TileShape_,
  class ElementA_,
  class StrideA_,
  class ElementB_,
  class StrideB_,
  class TiledMma_,
  class GmemTiledCopyA_,
  class SmemLayoutAtomA_,
  class SmemCopyAtomA_,
  class TransformA_,
  class GmemTiledCopyB_,
  class SmemLayoutAtomB_,
  class SmemCopyAtomB_,
  class TransformB_>
struct CollectiveMma<
    MainloopDispatchPtrArray<2, ArchTag_, ClusterShape_, KernelSchedule_>,
    TileShape_,
    ElementA_,
    StrideA_,
    ElementB_,
    StrideB_,
    TiledMma_,
    GmemTiledCopyA_,
    SmemLayoutAtomA_,
    SmemCopyAtomA_,
    TransformA_,
    GmemTiledCopyB_,
    SmemLayoutAtomB_,
    SmemCopyAtomB_,
    TransformB_>
    : public CollectiveMma<
          MainloopDispatch<2, ArchTag_, ClusterShape_, KernelSchedule_>,
          TileShape_,
          ElementA_,
          StrideA_,
          ElementB_,
          StrideB_,
          TiledMma_,
          GmemTiledCopyA_,
          SmemLayoutAtomA_,
          SmemCopyAtomA_,
          TransformA_,
          GmemTiledCopyB_,
          SmemLayoutAtomB_,
          SmemCopyAtomB_,
          TransformB_>
{
  using Base = CollectiveMma<
      MainloopDispatch<2, ArchTag_, ClusterShape_, KernelSchedule_>,
      TileShape_,
      ElementA_,
      StrideA_,
      ElementB_,
      StrideB_,
      TiledMma_,
      GmemTiledCopyA_,
      SmemLayoutAtomA_,
      SmemCopyAtomA_,
      TransformA_,
      GmemTiledCopyB_,
      SmemLayoutAtomB_,
      SmemCopyAtomB_,
      TransformB_>;
      
  using StrideA = StrideA_;
  using StrideB = StrideB_;
  using UnderlyingStrideA = hute::remove_pointer_t<StrideA>;  
  using UnderlyingStrideB = hute::remove_pointer_t<StrideB>;

  using typename Base::SharedStorage;

  struct Arguments {
    ElementA_ const** ptr_A;
    StrideA dA;
    ElementB_ const** ptr_B;
    StrideB dB;
  };

  using Params = Arguments;

  CollectiveMma() = default;

  template <class ProblemShape>
  static constexpr Params
  to_underlying_arguments(ProblemShape const& _, Arguments const& args, void* workspace) {
    (void) workspace;
    return args;
  }
};

} // namespace hytlass::gemm::collective

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