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 // SPDX-License-Identifier: MIT
 // Copyright (c) 2018-2025, Advanced Micro Devices, Inc. All rights reserved.
  
 #pragma once
  
 #include "ck/utility/common_header.hpp"
 #include "ck/tensor_description/multi_index_transform_helper.hpp"
 #include "ck/tensor_description/tensor_descriptor.hpp"
 #include "ck/tensor_description/tensor_descriptor_helper.hpp"
 #include "ck/tensor_operation/gpu/device/gemm_specialization.hpp"
 #include "ck/tensor_operation/gpu/grid/block_to_ctile_map.hpp"
 #include "ck/tensor_operation/gpu/grid/gridwise_gemm_pipeline_selector.hpp"
 #include "ck/tensor_operation/gpu/block/blockwise_gemm_xdlops.hpp"
 #include "ck/tensor_operation/gpu/block/thread_group_tensor_slice_transfer_v4r1.hpp"
 #include "ck/tensor_operation/gpu/thread/threadwise_tensor_slice_transfer.hpp"
 #include "ck/tensor_operation/gpu/element/element_wise_operation.hpp"
  
 namespace ck {
  
 template <typename GridwiseGemm,
           typename FloatAB,
           typename FloatC,
           typename AGridDesc_K0_M_K1,
           typename BGridDesc_K0_N_K1,
           typename CGridDesc_M_N,
           bool HasMainKBlockLoop>
 __global__ void
 #if CK_USE_LAUNCH_BOUNDS
 __launch_bounds__(CK_MAX_THREAD_PER_BLOCK, CK_MIN_BLOCK_PER_CU)
 #endif
 #if CK_USE_WAVES_PER_EU
     __attribute__((amdgpu_waves_per_eu(CK_MIN_WAVES_PER_EU, CK_MAX_WAVES_PER_EU)))
 #endif
     kernel_gemm_xdlops_v2r3(const FloatAB* __restrict__ p_a_grid,
                             const FloatAB* __restrict__ p_b_grid,
                             FloatC* __restrict__ p_c_grid,
                             const AGridDesc_K0_M_K1 a_grid_desc_k0_m_k1,
                             const BGridDesc_K0_N_K1 b_grid_desc_k0_n_k1,
                             const CGridDesc_M_N c_grid_desc_m_n)
 {
 #if defined(__gfx908__) || defined(__gfx90a__) || defined(__gfx94__) || defined(__gfx11__) || \
     defined(__gfx12__)
     if constexpr(GridwiseGemm::template IsValidCompilationParameter<>())
     {
         __shared__ char p_shared[GridwiseGemm::GetSharedMemoryNumberOfByte()];
  
         GridwiseGemm::template Run<HasMainKBlockLoop>(p_a_grid,
                                                       p_b_grid,
                                                       p_c_grid,
                                                       p_shared,
                                                       a_grid_desc_k0_m_k1,
                                                       b_grid_desc_k0_n_k1,
                                                       c_grid_desc_m_n);
     }
 #else
     ignore = p_a_grid;
     ignore = p_b_grid;
     ignore = p_c_grid;
     ignore = a_grid_desc_k0_m_k1;
     ignore = b_grid_desc_k0_n_k1;
     ignore = c_grid_desc_m_n;
 #endif // end of if (defined(__gfx908__) || defined(__gfx90a__))
 }
  
 template <typename GridwiseGemm, bool HasMainKBlockLoop>
 __global__ void
 #if CK_USE_LAUNCH_BOUNDS
 __launch_bounds__(CK_MAX_THREAD_PER_BLOCK, CK_MIN_BLOCK_PER_CU)
 #endif
 #if CK_USE_WAVES_PER_EU
     __attribute__((amdgpu_waves_per_eu(CK_MIN_WAVES_PER_EU, CK_MAX_WAVES_PER_EU)))
 #endif
     kernel_gemm_xdlops_v2r3(const typename GridwiseGemm::Argument karg)
 {
 #if defined(__gfx908__) || defined(__gfx90a__) || defined(__gfx94__) || defined(__gfx11__) || \
     defined(__gfx12__)
     if constexpr(GridwiseGemm::template IsValidCompilationParameter<>())
     {
         __shared__ char p_shared[GridwiseGemm::GetSharedMemoryNumberOfByte()];
  
         const auto a_grid_desc_k0_m_k1 =
             amd_wave_read_first_lane(GridwiseGemm::MakeAGridDescriptor_K0_M_K1(
                 karg.M, karg.MPadded, karg.K, karg.K0, karg.StrideA));
         const auto b_grid_desc_k0_n_k1 =
             amd_wave_read_first_lane(GridwiseGemm::MakeBGridDescriptor_K0_N_K1(
                 karg.K, karg.N, karg.NPadded, karg.K0, karg.StrideB));
         const auto c_grid_desc_m_n = amd_wave_read_first_lane(GridwiseGemm::MakeCGridDescriptor_M_N(
             karg.M, karg.MPadded, karg.N, karg.NPadded, karg.StrideC));
  
         GridwiseGemm::template Run<HasMainKBlockLoop>(karg.p_a_grid,
                                                       karg.p_b_grid,
                                                       karg.p_c_grid,
                                                       p_shared,
                                                       a_grid_desc_k0_m_k1,
                                                       b_grid_desc_k0_n_k1,
                                                       c_grid_desc_m_n);
     }
 #else
     ignore = karg;
 #endif // end of if (defined(__gfx908__) || defined(__gfx90a__))
 }
  
 template <index_t BlockSize,
           typename FloatAB,
           typename FloatAcc,
           typename FloatC,
           InMemoryDataOperationEnum CGlobalMemoryDataOperation,
           typename AElementwiseOperation,
           typename BElementwiseOperation,
           typename CElementwiseOperation,
           index_t MPerBlock,
           index_t NPerBlock,
           index_t K0PerBlock,
           index_t MPerXdl,
           index_t NPerXdl,
           index_t K1Value,
           index_t MXdlPerWave,
           index_t NXdlPerWave,
           typename ABlockTransferThreadClusterLengths_K0_M_K1,
           typename ABlockTransferThreadClusterArrangeOrder,
           typename ABlockTransferSrcAccessOrder,
           index_t ABlockTransferSrcVectorDim,
           index_t ABlockTransferSrcScalarPerVector,
           index_t ABlockTransferDstScalarPerVector_K1,
           bool AThreadTransferSrcResetCoordinateAfterRun,
           bool ABlockLdsExtraM,
           typename BBlockTransferThreadClusterLengths_K0_N_K1,
           typename BBlockTransferThreadClusterArrangeOrder,
           typename BBlockTransferSrcAccessOrder,
           index_t BBlockTransferSrcVectorDim,
           index_t BBlockTransferSrcScalarPerVector,
           index_t BBlockTransferDstScalarPerVector_K1,
           bool BThreadTransferSrcResetCoordinateAfterRun,
           bool BBlockLdsExtraN,
           typename CThreadTransferSrcDstAccessOrder,
           index_t CThreadTransferSrcDstVectorDim,
           index_t CThreadTransferDstScalarPerVector,
           index_t NumGemmKPrefetchStage = 1,
           LoopScheduler LoopSched       = make_default_loop_scheduler(),
           PipelineVersion PipelineVer   = PipelineVersion::v1>
 struct GridwiseGemm_k0mk1_k0nk1_mn_xdlops_v2r3
 {
     static constexpr auto I0 = Number<0>{};
     static constexpr auto I1 = Number<1>{};
     static constexpr auto I2 = Number<2>{};
     static constexpr auto I3 = Number<3>{};
     static constexpr auto I4 = Number<4>{};
     static constexpr auto I5 = Number<5>{};
     static constexpr auto I6 = Number<6>{};
     static constexpr auto I7 = Number<7>{};
  
     // K1 should be Number<...>
     static constexpr bool is_single_rate_mfma =
         (((is_same<FloatAB, half_t>::value || is_same<FloatAB, bhalf_t>::value) && K1Value <= 4) ||
          (is_same<FloatAB, int8_t>::value && K1Value <= 8) ||
          ((is_same<FloatAB, f8_t>::value || is_same<FloatAB, bf8_t>::value) && K1Value < 32))
             ? true
             : false;
     static constexpr auto is_scale_mfma = false;
     static constexpr auto K1            = Number<math::max(
         K1Value,
         MfmaSelector<FloatAB, MPerXdl, NPerXdl, FloatAB, is_single_rate_mfma, is_scale_mfma>::
             selected_mfma.k_per_blk)>{};
  
     using ThisThreadBlock = ThisThreadBlock<BlockSize>;
  
     using ElementDataTypeAB = conditional_t<is_same_v<FloatAB, ck::tf32_t>, float, FloatAB>;
  
     __host__ static auto CalculateGridSize(index_t M, index_t N)
     {
         return std::make_tuple(Block2CTileMap::CalculateGridSize(M, N), 1, 1);
     }
  
     template <typename CGridDesc_M_N>
     __host__ static auto CalculateGridSize(const CGridDesc_M_N& c_grid_desc_m_n)
     {
         return std::make_tuple(Block2CTileMap::CalculateGridSize(c_grid_desc_m_n), 1, 1);
     }
  
     template <typename>
     __host__ static auto CalculateGridSize(index_t M, index_t N)
     {
         return std::make_tuple(Block2CTileMap::CalculateGridSize(M, N), 1, 1);
     }
  
     __host__ static auto CalculateMPadded(index_t M)
     {
         return math::integer_divide_ceil(M, MPerBlock) * MPerBlock;
     }
  
     __host__ static auto CalculateNPadded(index_t N)
     {
         return math::integer_divide_ceil(N, NPerBlock) * NPerBlock;
     }
  
     __host__ static auto CalculateK0(index_t K) { return math::integer_divide_ceil(K, K1Value); }
  
     // Argument
     struct Problem
     {
         __host__ Problem(index_t M_,
                          index_t N_,
                          index_t K_,
                          index_t StrideA_,
                          index_t StrideB_,
                          index_t StrideC_)
             : M{M_},
               N{N_},
               K{K_},
               StrideA{StrideA_},
               StrideB{StrideB_},
               StrideC{StrideC_},
               MPadded{CalculateMPadded(M_)},
               NPadded{CalculateNPadded(N_)},
               K0{CalculateK0(K_)}
         {
         }
  
         __host__ void Print() const
         {
             std::cout << "problem {" << "M:" << M << ", " << "N:" << N << ", " << "K:" << K << ", "
                       << "SA:" << StrideA << ", " << "SB:" << StrideB << ", " << "SC:" << StrideC
                       << ", " << "MP:" << MPadded << ", " << "NP:" << NPadded << ", " << "K0:" << K0
                       << "}" << std::endl;
         }
  
         index_t M;
         index_t N;
         index_t K;
         index_t StrideA;
         index_t StrideB;
         index_t StrideC;
         index_t MPadded;
         index_t NPadded;
         index_t K0;
     };
  
     // Argument
     struct Argument : public Problem, public tensor_operation::device::BaseArgument
     {
         __host__ Argument(const ElementDataTypeAB* p_a_grid_,
                           const ElementDataTypeAB* p_b_grid_,
                           FloatC* p_c_grid_,
                           index_t M_,
                           index_t N_,
                           index_t K_,
                           index_t StrideA_,
                           index_t StrideB_,
                           index_t StrideC_)
             : Problem{M_, N_, K_, StrideA_, StrideB_, StrideC_},
               p_a_grid{p_a_grid_},
               p_b_grid{p_b_grid_},
               p_c_grid{p_c_grid_}
         {
         }
  
         const ElementDataTypeAB* p_a_grid;
         const ElementDataTypeAB* p_b_grid;
         FloatC* p_c_grid;
     };
  
     using GridwiseGemmPipe = remove_cvref_t<
         decltype(GridwiseGemmPipeline_Selector<PipelineVer, NumGemmKPrefetchStage, LoopSched>())>;
  
     // denorm test fix, required to work around fp16 mfma issue
     // we convert fp16->fp32->bf16 and execute bf16 mfma instruction
     // when mfma if fixed, remove this section and update
     // FloatABAdjusted -> FloatAB throughout this file
 #if CK_GFX90A_DENORM_WORKAROUND
     using FloatABAdjusted = conditional_t<is_same_v<FloatAB, ck::half_t>, ck::bhalf_t, FloatAB>;
 #else
     using FloatABAdjusted = FloatAB;
 #endif
  
     __host__ __device__ static constexpr auto GetABlockDescriptor_K0PerBlock_MPerBlock_K1()
     {
         constexpr auto max_lds_align = K1;
  
         // A matrix in LDS memory, dst of blockwise copy
         constexpr auto a_block_desc_k0_m_k1 = [&]() {
             if constexpr(ABlockLdsExtraM)
             {
                 return make_naive_tensor_descriptor(
                     make_tuple(Number<K0PerBlock>{}, Number<MPerBlock>{}, K1),
                     make_tuple(Number<MPerBlock + 1>{} * K1, K1, I1));
             }
             else
             {
                 return make_naive_tensor_descriptor_aligned(
                     make_tuple(Number<K0PerBlock>{}, Number<MPerBlock>{}, K1), max_lds_align);
             }
         }();
  
         return a_block_desc_k0_m_k1;
     }
  
     __host__ __device__ static constexpr auto GetBBlockDescriptor_K0PerBlock_NPerBlock_K1()
     {
         constexpr auto max_lds_align = K1;
  
         // B matrix in LDS memory, dst of blockwise copy
         constexpr auto b_block_desc_k0_n_k1 = [&]() {
             if constexpr(BBlockLdsExtraN)
             {
                 return make_naive_tensor_descriptor(
                     make_tuple(Number<K0PerBlock>{}, Number<NPerBlock>{}, K1),
                     make_tuple(Number<NPerBlock + 1>{} * K1, K1, I1));
             }
             else
             {
                 return make_naive_tensor_descriptor_aligned(
                     make_tuple(Number<K0PerBlock>{}, Number<NPerBlock>{}, K1), max_lds_align);
             }
         }();
  
         return b_block_desc_k0_n_k1;
     }
  
     __host__ __device__ static constexpr index_t GetSharedMemoryNumberOfByte()
     {
         // LDS allocation for A and B: be careful of alignment
         constexpr auto a_block_desc_k0_m_k1 = GetABlockDescriptor_K0PerBlock_MPerBlock_K1();
  
         constexpr auto b_block_desc_k0_n_k1 = GetBBlockDescriptor_K0PerBlock_NPerBlock_K1();
  
         constexpr auto max_lds_align = K1;
  
         constexpr auto a_block_space_size_aligned =
             math::integer_least_multiple(a_block_desc_k0_m_k1.GetElementSpaceSize(), max_lds_align);
  
         constexpr auto b_block_space_size_aligned =
             math::integer_least_multiple(b_block_desc_k0_n_k1.GetElementSpaceSize(), max_lds_align);
  
         return (a_block_space_size_aligned + b_block_space_size_aligned) *
                sizeof(ElementDataTypeAB);
     }
  
     template <
         InMemoryDataOperationEnum CGlobalMemoryDataOperation_ = InMemoryDataOperationEnum::Set>
     __device__ static bool constexpr IsValidCompilationParameter()
     {
         return ck::tensor_operation::device::IsValidGemmCompilationParameter<
             BlockSize,
             MPerBlock,
             NPerBlock,
             MPerXdl,
             NPerXdl,
             MXdlPerWave,
             NXdlPerWave,
             FloatC,
             CGlobalMemoryDataOperation>();
     }
  
     template <typename AGridDesc_K0_M_K1, typename BGridDesc_K0_N_K1, typename CGridDesc_M_N>
     __host__ __device__ static constexpr bool
     CheckValidity(const AGridDesc_K0_M_K1& a_grid_desc_k0_m_k1,
                   const BGridDesc_K0_N_K1& b_grid_desc_k0_n_k1,
                   const CGridDesc_M_N& c_grid_desc_m_n)
     {
         static_assert(is_known_at_compile_time<remove_cv_t<decltype(K1)>>::value,
                       "wrong! K1 need to be known at compile-time");
  
         static_assert((MPerBlock % (MPerXdl * MXdlPerWave) == 0) &&
                           (NPerBlock % (NXdlPerWave * NPerXdl)) == 0,
                       "Invalid tuning param!");
  
         const auto M  = a_grid_desc_k0_m_k1.GetLength(I1);
         const auto N  = b_grid_desc_k0_n_k1.GetLength(I1);
         const auto K0 = a_grid_desc_k0_m_k1.GetLength(I0);
  
         if(!(M == c_grid_desc_m_n.GetLength(I0) && N == c_grid_desc_m_n.GetLength(I1) &&
              K0 == b_grid_desc_k0_n_k1.GetLength(I0) && K1 == a_grid_desc_k0_m_k1.GetLength(I2) &&
              K1 == b_grid_desc_k0_n_k1.GetLength(I2)))
             return false;
  
         if(!(M % MPerBlock == 0 && N % NPerBlock == 0 && K0 % K0PerBlock == 0))
             return false;
  
         // check gridwise gemm pipeline
         const auto num_k_loop = K0 / K0PerBlock;
  
         if(!GridwiseGemmPipe::IsSupported(num_k_loop))
         {
             return false;
         }
  
         // TODO: also check validity of all components (blockwise-copy, threadwise-copy, etc)
         return true;
     }
  
     __host__ static constexpr bool CheckValidity(const Problem& problem)
     {
         static_assert(is_known_at_compile_time<remove_cv_t<decltype(K1)>>::value,
                       "wrong! K1 need to be known at compile-time");
  
         static_assert((MPerBlock % (MPerXdl * MXdlPerWave) == 0) &&
                           (NPerBlock % (NXdlPerWave * NPerXdl)) == 0,
                       "Invalid tuning param!");
  
         // check gridwise gemm pipeline
         const auto num_k_loop = math::integer_divide_ceil(problem.K0, K0PerBlock);
         if(!GridwiseGemmPipe::IsSupported(num_k_loop))
         {
             return false;
         }
  
         // TODO: also check validity of all components (blockwise-copy, threadwise-copy, etc)
         return true;
     }
  
     __host__ static constexpr bool CalculateHasMainKBlockLoop(index_t K)
     {
         const index_t num_loop = math::integer_divide_ceil(K, K0PerBlock * K1);
  
         return GridwiseGemmPipe::CalculateHasMainLoop(num_loop);
     }
  
     template <typename CGridDesc>
     __host__ __device__ static constexpr auto
     MakeCGridDescriptor_M0_N0_M1_N1_M2_M3_M4_N2(const CGridDesc& c_grid_desc_m_n)
     {
         constexpr auto max_lds_align = K1;
  
         // A matrix in LDS memory, dst of blockwise copy
         constexpr auto a_block_desc_k0_m_k1 = [&]() {
             if constexpr(ABlockLdsExtraM)
             {
                 return make_naive_tensor_descriptor(
                     make_tuple(Number<K0PerBlock>{}, Number<MPerBlock>{}, K1),
                     make_tuple(Number<MPerBlock + 1>{} * K1, K1, I1));
             }
             else
             {
                 return make_naive_tensor_descriptor_aligned(
                     make_tuple(Number<K0PerBlock>{}, Number<MPerBlock>{}, K1), max_lds_align);
             }
         }();
  
         // B matrix in LDS memory, dst of blockwise copy
         constexpr auto b_block_desc_k0_n_k1 = [&]() {
             if constexpr(BBlockLdsExtraN)
             {
                 return make_naive_tensor_descriptor(
                     make_tuple(Number<K0PerBlock>{}, Number<NPerBlock>{}, K1),
                     make_tuple(Number<NPerBlock + 1>{} * K1, K1, I1));
             }
             else
             {
                 return make_naive_tensor_descriptor_aligned(
                     make_tuple(Number<K0PerBlock>{}, Number<NPerBlock>{}, K1), max_lds_align);
             }
         }();
  
         using BlockwiseGemm =
             BlockwiseGemmXdlops_k0mk1_k0nk1_m0n0m1n1m2m3m4n2_v1<BlockSize,
                                                                 ElementDataTypeAB,
                                                                 ElementDataTypeAB,
                                                                 FloatAcc,
                                                                 decltype(a_block_desc_k0_m_k1),
                                                                 decltype(b_block_desc_k0_n_k1),
                                                                 MPerXdl,
                                                                 NPerXdl,
                                                                 MXdlPerWave,
                                                                 NXdlPerWave,
                                                                 K1,
                                                                 FloatABAdjusted,
                                                                 FloatABAdjusted>;
  
         return BlockwiseGemm::MakeCGridDescriptor_M0_N0_M1_N1_M2_M3_M4_N2(c_grid_desc_m_n);
     }
  
     // return block_id to C matrix tile idx (m0, n0) mapping
     using Block2CTileMap = BlockToCTileMap_M00_N0_M01Adapt<MPerBlock, NPerBlock>;
  
     template <bool HasMainKBlockLoop,
               typename AGridDesc_K0_M_K1,
               typename BGridDesc_K0_N_K1,
               typename CGridDesc_M_N>
     __device__ static void Run(const ElementDataTypeAB* p_a_grid,
                                const ElementDataTypeAB* p_b_grid,
                                FloatC* p_c_grid,
                                void* __restrict__ p_shared,
                                const AGridDesc_K0_M_K1& a_grid_desc_k0_m_k1,
                                const BGridDesc_K0_N_K1& b_grid_desc_k0_n_k1,
                                const CGridDesc_M_N& c_grid_desc_m_n)
     {
         const auto c_grid_desc_m0_n0_m1_n1_m2_m3_m4_n2 =
             MakeCGridDescriptor_M0_N0_M1_N1_M2_M3_M4_N2(c_grid_desc_m_n);
  
         const auto a_grid_buf = make_dynamic_buffer<AddressSpaceEnum::Global>(
             p_a_grid, a_grid_desc_k0_m_k1.GetElementSpaceSize());
         const auto b_grid_buf = make_dynamic_buffer<AddressSpaceEnum::Global>(
             p_b_grid, b_grid_desc_k0_n_k1.GetElementSpaceSize());
         auto c_grid_buf = make_dynamic_buffer<AddressSpaceEnum::Global>(
             p_c_grid, c_grid_desc_m0_n0_m1_n1_m2_m3_m4_n2.GetElementSpaceSize());
  
         const AElementwiseOperation a_element_op{};
         const BElementwiseOperation b_element_op{};
         const CElementwiseOperation c_element_op{};
  
         const auto block_2_ctile_map =
             Block2CTileMap{c_grid_desc_m_n.GetLength(I0), c_grid_desc_m_n.GetLength(I1)};
  
         // divide block work by [M, N]
         const auto block_work_idx =
             block_2_ctile_map.CalculateBottomIndex(make_multi_index(get_block_1d_id()));
  
         if(!block_2_ctile_map.ValidCTileIndex(
                block_work_idx,
                make_tuple(c_grid_desc_m0_n0_m1_n1_m2_m3_m4_n2.GetLength(I0),
                           c_grid_desc_m0_n0_m1_n1_m2_m3_m4_n2.GetLength(I1))))
         {
             return;
         }
  
         // HACK: this force m/n_block_data_idx_on_grid into SGPR
         const index_t m_block_data_idx_on_grid =
             __builtin_amdgcn_readfirstlane(block_work_idx[I0] * MPerBlock);
  
         const index_t n_block_data_idx_on_grid =
             __builtin_amdgcn_readfirstlane(block_work_idx[I1] * NPerBlock);
  
         // lds max alignment
         constexpr auto max_lds_align = K1;
  
         // A matrix in LDS memory, dst of blockwise copy
         constexpr auto a_block_desc_k0_m_k1 = GetABlockDescriptor_K0PerBlock_MPerBlock_K1();
  
         // B matrix in LDS memory, dst of blockwise copy
         constexpr auto b_block_desc_k0_n_k1 = GetBBlockDescriptor_K0PerBlock_NPerBlock_K1();
  
         // A matrix blockwise copy
         auto a_blockwise_copy =
             ThreadGroupTensorSliceTransfer_v4r1<ThisThreadBlock,
                                                 AElementwiseOperation,
                                                 ck::tensor_operation::element_wise::PassThrough,
                                                 InMemoryDataOperationEnum::Set,
                                                 Sequence<K0PerBlock, MPerBlock, K1>,
                                                 ABlockTransferThreadClusterLengths_K0_M_K1,
                                                 ABlockTransferThreadClusterArrangeOrder,
                                                 ElementDataTypeAB,
                                                 ElementDataTypeAB,
                                                 decltype(a_grid_desc_k0_m_k1),
                                                 decltype(a_block_desc_k0_m_k1),
                                                 ABlockTransferSrcAccessOrder,
                                                 Sequence<1, 0, 2>,
                                                 ABlockTransferSrcVectorDim,
                                                 2,
                                                 ABlockTransferSrcScalarPerVector,
                                                 ABlockTransferDstScalarPerVector_K1,
                                                 1,
                                                 1,
                                                 AThreadTransferSrcResetCoordinateAfterRun,
                                                 true,
                                                 NumGemmKPrefetchStage>(
                 a_grid_desc_k0_m_k1,
                 make_multi_index(0, m_block_data_idx_on_grid, 0),
                 a_element_op,
                 a_block_desc_k0_m_k1,
                 make_multi_index(0, 0, 0),
                 ck::tensor_operation::element_wise::PassThrough{});
  
         // B matrix blockwise copy
         auto b_blockwise_copy =
             ThreadGroupTensorSliceTransfer_v4r1<ThisThreadBlock,
                                                 BElementwiseOperation,
                                                 ck::tensor_operation::element_wise::PassThrough,
                                                 InMemoryDataOperationEnum::Set,
                                                 Sequence<K0PerBlock, NPerBlock, K1>,
                                                 BBlockTransferThreadClusterLengths_K0_N_K1,
                                                 BBlockTransferThreadClusterArrangeOrder,
                                                 ElementDataTypeAB,
                                                 ElementDataTypeAB,
                                                 decltype(b_grid_desc_k0_n_k1),
                                                 decltype(b_block_desc_k0_n_k1),
                                                 BBlockTransferSrcAccessOrder,
                                                 Sequence<1, 0, 2>,
                                                 BBlockTransferSrcVectorDim,
                                                 2,
                                                 BBlockTransferSrcScalarPerVector,
                                                 BBlockTransferDstScalarPerVector_K1,
                                                 1,
                                                 1,
                                                 BThreadTransferSrcResetCoordinateAfterRun,
                                                 true,
                                                 NumGemmKPrefetchStage>(
                 b_grid_desc_k0_n_k1,
                 make_multi_index(0, n_block_data_idx_on_grid, 0),
                 b_element_op,
                 b_block_desc_k0_n_k1,
                 make_multi_index(0, 0, 0),
                 ck::tensor_operation::element_wise::PassThrough{});
  
         // GEMM definition
         //   c_mtx += transpose(a_mtx) * b_mtx
         //     a_mtx[K0PerBlock, MPerBlock] is in LDS
         //     b_mtx[K0PerBlock, NPerBlock] is in LDS
         //     c_mtx[MPerBlock, NPerBlock] is distributed among threads, and saved in
         //       register
         // sanity check
         auto blockwise_gemm = BlockwiseGemmXdlops_k0mk1_k0nk1_m0n0m1n1m2m3m4n2_Selector<
             BlockSize,
             ElementDataTypeAB,
             ElementDataTypeAB,
             FloatAcc,
             decltype(a_block_desc_k0_m_k1),
             decltype(b_block_desc_k0_n_k1),
             MPerXdl,
             NPerXdl,
             MXdlPerWave,
             NXdlPerWave,
             K1,
             LoopSched,
             FloatABAdjusted,
             FloatABAdjusted>();
  
         auto c_thread_buf = blockwise_gemm.GetCThreadBuffer();
  
         // LDS allocation for A and B: be careful of alignment
         constexpr auto a_block_space_size_aligned =
             math::integer_least_multiple(a_block_desc_k0_m_k1.GetElementSpaceSize(), max_lds_align);
  
         auto a_block_buf = make_dynamic_buffer<AddressSpaceEnum::Lds>(
             static_cast<ElementDataTypeAB*>(p_shared), a_block_desc_k0_m_k1.GetElementSpaceSize());
  
         auto b_block_buf = make_dynamic_buffer<AddressSpaceEnum::Lds>(
             static_cast<ElementDataTypeAB*>(p_shared) + a_block_space_size_aligned,
             b_block_desc_k0_n_k1.GetElementSpaceSize());
  
         constexpr auto a_block_slice_copy_step = make_multi_index(K0PerBlock, 0, 0);
         constexpr auto b_block_slice_copy_step = make_multi_index(K0PerBlock, 0, 0);
  
         // gridwise GEMM pipeline
         const auto K0                       = a_grid_desc_k0_m_k1.GetLength(I0);
         const index_t num_k_block_main_loop = __builtin_amdgcn_readfirstlane(K0 / K0PerBlock);
  
         GridwiseGemmPipe::template Run<HasMainKBlockLoop>(a_grid_desc_k0_m_k1,
                                                           a_block_desc_k0_m_k1,
                                                           a_blockwise_copy,
                                                           a_grid_buf,
                                                           a_block_buf,
                                                           a_block_slice_copy_step,
                                                           b_grid_desc_k0_n_k1,
                                                           b_block_desc_k0_n_k1,
                                                           b_blockwise_copy,
                                                           b_grid_buf,
                                                           b_block_buf,
                                                           b_block_slice_copy_step,
                                                           blockwise_gemm,
                                                           c_thread_buf,
                                                           num_k_block_main_loop);
  
         // output: register to global memory
         {
             constexpr auto c_thread_desc_m0_n0_m1_n1_m2_m3_m4_n2 =
                 blockwise_gemm.GetCThreadDescriptor_M0_N0_M1_N1_M2_M3_M4_N2();
  
             constexpr auto c_block_desc_m0_n0_m1_n1_m2_m3_m4_n2 =
                 blockwise_gemm.GetCBlockDescriptor_M0_N0_M1_N1_M2_M3_M4_N2();
  
             constexpr auto M0 = c_block_desc_m0_n0_m1_n1_m2_m3_m4_n2.GetLength(I0);
             constexpr auto N0 = c_block_desc_m0_n0_m1_n1_m2_m3_m4_n2.GetLength(I1);
             constexpr auto M1 = c_block_desc_m0_n0_m1_n1_m2_m3_m4_n2.GetLength(I2);
             constexpr auto N1 = c_block_desc_m0_n0_m1_n1_m2_m3_m4_n2.GetLength(I3);
             constexpr auto M2 = c_block_desc_m0_n0_m1_n1_m2_m3_m4_n2.GetLength(I4);
             constexpr auto M3 = c_block_desc_m0_n0_m1_n1_m2_m3_m4_n2.GetLength(I5);
             constexpr auto M4 = c_block_desc_m0_n0_m1_n1_m2_m3_m4_n2.GetLength(I6);
             constexpr auto N2 = c_block_desc_m0_n0_m1_n1_m2_m3_m4_n2.GetLength(I7);
  
             // calculate origin of thread output tensor on global memory
             //     blockwise GEMM c matrix starting index
             const auto c_thread_mtx_on_block =
                 blockwise_gemm.CalculateCThreadOriginDataIndex(I0, I0, I0, I0);
  
             const index_t m_thread_data_on_grid =
                 m_block_data_idx_on_grid + c_thread_mtx_on_block[I0];
  
             const index_t n_thread_data_on_grid =
                 n_block_data_idx_on_grid + c_thread_mtx_on_block[I1];
  
             const auto m_thread_data_on_grid_to_m0_m1_m2_m3_m4_adaptor =
                 make_single_stage_tensor_adaptor(
                     make_tuple(make_merge_transform(make_tuple(M0, M1, M2, M3, M4))),
                     make_tuple(Sequence<0, 1, 2, 3, 4>{}),
                     make_tuple(Sequence<0>{}));
  
             const auto m_thread_data_on_grid_idx =
                 m_thread_data_on_grid_to_m0_m1_m2_m3_m4_adaptor.CalculateBottomIndex(
                     make_multi_index(m_thread_data_on_grid));
  
             const auto n_thread_data_on_grid_to_n0_n1_n2_adaptor = make_single_stage_tensor_adaptor(
                 make_tuple(make_merge_transform(make_tuple(N0, N1, N2))),
                 make_tuple(Sequence<0, 1, 2>{}),
                 make_tuple(Sequence<0>{}));
  
             const auto n_thread_data_on_grid_idx =
                 n_thread_data_on_grid_to_n0_n1_n2_adaptor.CalculateBottomIndex(
                     make_multi_index(n_thread_data_on_grid));
  
             auto c_thread_copy =
                 ThreadwiseTensorSliceTransfer_v1r3<FloatAcc,
                                                    FloatC,
                                                    decltype(c_thread_desc_m0_n0_m1_n1_m2_m3_m4_n2),
                                                    decltype(c_grid_desc_m0_n0_m1_n1_m2_m3_m4_n2),
                                                    CElementwiseOperation,
                                                    Sequence<M0, N0, I1, I1, M2, I1, M4, I1>,
                                                    CThreadTransferSrcDstAccessOrder,
                                                    CThreadTransferSrcDstVectorDim,
                                                    CThreadTransferDstScalarPerVector,
                                                    CGlobalMemoryDataOperation,
                                                    1,
                                                    true>{
                     c_grid_desc_m0_n0_m1_n1_m2_m3_m4_n2,
                     make_multi_index(m_thread_data_on_grid_idx[I0],
                                      n_thread_data_on_grid_idx[I0],
                                      m_thread_data_on_grid_idx[I1],
                                      n_thread_data_on_grid_idx[I1],
                                      m_thread_data_on_grid_idx[I2],
                                      m_thread_data_on_grid_idx[I3],
                                      m_thread_data_on_grid_idx[I4],
                                      n_thread_data_on_grid_idx[I2]),
                     c_element_op};
  
             c_thread_copy.Run(c_thread_desc_m0_n0_m1_n1_m2_m3_m4_n2,
                               make_tuple(I0, I0, I0, I0, I0, I0, I0, I0),
                               c_thread_buf,
                               c_grid_desc_m0_n0_m1_n1_m2_m3_m4_n2,
                               c_grid_buf);
         }
     }
 };
  
 template <index_t BlockSize,
           typename FloatAB,
           typename FloatAcc,
           typename FloatC,
           InMemoryDataOperationEnum CGlobalMemoryDataOperation,
           typename ALayout,
           typename BLayout,
           typename CLayout,
           typename AElementwiseOperation,
           typename BElementwiseOperation,
           typename CElementwiseOperation,
           tensor_operation::device::GemmSpecialization GemmSpec,
           index_t MPerBlock,
           index_t NPerBlock,
           index_t K0PerBlock,
           index_t MPerXdl,
           index_t NPerXdl,
           index_t K1Value,
           index_t MXdlPerWave,
           index_t NXdlPerWave,
           typename ABlockTransferThreadClusterLengths_K0_M_K1,
           typename ABlockTransferThreadClusterArrangeOrder,
           typename ABlockTransferSrcAccessOrder,
           index_t ABlockTransferSrcVectorDim,
           index_t ABlockTransferSrcScalarPerVector,
           index_t ABlockTransferDstScalarPerVector_K1,
           bool AThreadTransferSrcResetCoordinateAfterRun,
           bool ABlockLdsExtraM,
           typename BBlockTransferThreadClusterLengths_K0_N_K1,
           typename BBlockTransferThreadClusterArrangeOrder,
           typename BBlockTransferSrcAccessOrder,
           index_t BBlockTransferSrcVectorDim,
           index_t BBlockTransferSrcScalarPerVector,
           index_t BBlockTransferDstScalarPerVector_K1,
           bool BThreadTransferSrcResetCoordinateAfterRun,
           bool BBlockLdsExtraN,
           typename CThreadTransferSrcDstAccessOrder,
           index_t CThreadTransferSrcDstVectorDim,
           index_t CThreadTransferDstScalarPerVector,
           index_t NumGemmKPrefetchStage = 1,
           LoopScheduler LoopSched       = make_default_loop_scheduler(),
           PipelineVersion PipelineVer   = PipelineVersion::v1>
 struct GridwiseGemm_k0mk1_k0nk1_mn_xdlops_v2r3_ext
     : GridwiseGemm_k0mk1_k0nk1_mn_xdlops_v2r3<BlockSize,
                                               FloatAB,
                                               FloatAcc,
                                               FloatC,
                                               CGlobalMemoryDataOperation,
                                               AElementwiseOperation,
                                               BElementwiseOperation,
                                               CElementwiseOperation,
                                               MPerBlock,
                                               NPerBlock,
                                               K0PerBlock,
                                               MPerXdl,
                                               NPerXdl,
                                               K1Value,
                                               MXdlPerWave,
                                               NXdlPerWave,
                                               ABlockTransferThreadClusterLengths_K0_M_K1,
                                               ABlockTransferThreadClusterArrangeOrder,
                                               ABlockTransferSrcAccessOrder,
                                               ABlockTransferSrcVectorDim,
                                               ABlockTransferSrcScalarPerVector,
                                               ABlockTransferDstScalarPerVector_K1,
                                               AThreadTransferSrcResetCoordinateAfterRun,
                                               ABlockLdsExtraM,
                                               BBlockTransferThreadClusterLengths_K0_N_K1,
                                               BBlockTransferThreadClusterArrangeOrder,
                                               BBlockTransferSrcAccessOrder,
                                               BBlockTransferSrcVectorDim,
                                               BBlockTransferSrcScalarPerVector,
                                               BBlockTransferDstScalarPerVector_K1,
                                               BThreadTransferSrcResetCoordinateAfterRun,
                                               BBlockLdsExtraN,
                                               CThreadTransferSrcDstAccessOrder,
                                               CThreadTransferSrcDstVectorDim,
                                               CThreadTransferDstScalarPerVector,
                                               NumGemmKPrefetchStage,
                                               LoopSched,
                                               PipelineVer>
 {
     using Parent =
         GridwiseGemm_k0mk1_k0nk1_mn_xdlops_v2r3<BlockSize,
                                                 FloatAB,
                                                 FloatAcc,
                                                 FloatC,
                                                 CGlobalMemoryDataOperation,
                                                 AElementwiseOperation,
                                                 BElementwiseOperation,
                                                 CElementwiseOperation,
                                                 MPerBlock,
                                                 NPerBlock,
                                                 K0PerBlock,
                                                 MPerXdl,
                                                 NPerXdl,
                                                 K1Value,
                                                 MXdlPerWave,
                                                 NXdlPerWave,
                                                 ABlockTransferThreadClusterLengths_K0_M_K1,
                                                 ABlockTransferThreadClusterArrangeOrder,
                                                 ABlockTransferSrcAccessOrder,
                                                 ABlockTransferSrcVectorDim,
                                                 ABlockTransferSrcScalarPerVector,
                                                 ABlockTransferDstScalarPerVector_K1,
                                                 AThreadTransferSrcResetCoordinateAfterRun,
                                                 ABlockLdsExtraM,
                                                 BBlockTransferThreadClusterLengths_K0_N_K1,
                                                 BBlockTransferThreadClusterArrangeOrder,
                                                 BBlockTransferSrcAccessOrder,
                                                 BBlockTransferSrcVectorDim,
                                                 BBlockTransferSrcScalarPerVector,
                                                 BBlockTransferDstScalarPerVector_K1,
                                                 BThreadTransferSrcResetCoordinateAfterRun,
                                                 BBlockLdsExtraN,
                                                 CThreadTransferSrcDstAccessOrder,
                                                 CThreadTransferSrcDstVectorDim,
                                                 CThreadTransferDstScalarPerVector,
                                                 NumGemmKPrefetchStage,
                                                 LoopSched,
                                                 PipelineVer>;
  
     using typename Parent::GridwiseGemmPipe;
     using typename Parent::Problem;
  
     using Parent::I1;
  
     using Parent::K1;
  
     __device__ static auto
     MakeAGridDescriptor_K0_M_K1(index_t M, index_t MPad, index_t K, index_t K0, index_t StrideA)
     {
         const auto a_grid_desc_m_k = [&]() {
             if constexpr(is_same<tensor_layout::gemm::RowMajor, ALayout>::value)
             {
                 return make_naive_tensor_descriptor(make_tuple(M, K), make_tuple(StrideA, I1));
             }
             else if constexpr(is_same<tensor_layout::gemm::ColumnMajor, ALayout>::value)
             {
                 return make_naive_tensor_descriptor(make_tuple(M, K), make_tuple(I1, StrideA));
             }
         }();
  
         if constexpr(GemmSpec == tensor_operation::device::GemmSpecialization::MNKPadding)
         {
             const auto K0Pad = math::integer_divide_ceil(K0, K0PerBlock) * K0PerBlock;
             const auto KPad  = K0Pad * K1Value;
  
             const auto a_grid_desc_m_kpad = transform_tensor_descriptor(
                 a_grid_desc_m_k,
                 make_tuple(make_pass_through_transform(M), make_right_pad_transform(K, KPad - K)),
                 make_tuple(Sequence<0>{}, Sequence<1>{}),
                 make_tuple(Sequence<0>{}, Sequence<1>{}));
  
             return transform_tensor_descriptor(
                 a_grid_desc_m_kpad,
                 make_tuple(make_unmerge_transform(make_tuple(K0Pad, K1Value)),
                            make_right_pad_transform(M, MPad - M)),
                 make_tuple(Sequence<1>{}, Sequence<0>{}),
                 make_tuple(Sequence<0, 2>{}, Sequence<1>{}));
         }
         else if constexpr(GemmSpec == tensor_operation::device::GemmSpecialization::MNPadding)
         {
             return transform_tensor_descriptor(
                 a_grid_desc_m_k,
                 make_tuple(make_unmerge_transform(make_tuple(K0, K1Value)),
                            make_right_pad_transform(M, MPad - M)),
                 make_tuple(Sequence<1>{}, Sequence<0>{}),
                 make_tuple(Sequence<0, 2>{}, Sequence<1>{}));
         }
         else
         {
             return transform_tensor_descriptor(
                 a_grid_desc_m_k,
                 make_tuple(make_unmerge_transform(make_tuple(K0, K1Value)),
                            make_pass_through_transform(M)),
                 make_tuple(Sequence<1>{}, Sequence<0>{}),
                 make_tuple(Sequence<0, 2>{}, Sequence<1>{}));
         }
     }
  
     __device__ static auto
     MakeBGridDescriptor_K0_N_K1(index_t K, index_t N, index_t NPad, index_t K0, index_t StrideB)
     {
         const auto b_grid_desc_k_n = [&]() {
             if constexpr(is_same<tensor_layout::gemm::RowMajor, BLayout>::value)
             {
                 return make_naive_tensor_descriptor(make_tuple(K, N), make_tuple(StrideB, I1));
             }
             else if constexpr(is_same<tensor_layout::gemm::ColumnMajor, BLayout>::value)
             {
                 return make_naive_tensor_descriptor(make_tuple(K, N), make_tuple(I1, StrideB));
             }
         }();
  
         if constexpr(GemmSpec == tensor_operation::device::GemmSpecialization::MNKPadding)
         {
             const auto K0Pad = math::integer_divide_ceil(K0, K0PerBlock) * K0PerBlock;
             const auto KPad  = K0Pad * K1Value;
  
             const auto b_grid_desc_kpad_n = transform_tensor_descriptor(
                 b_grid_desc_k_n,
                 make_tuple(make_right_pad_transform(K, KPad - K), make_pass_through_transform(N)),
                 make_tuple(Sequence<0>{}, Sequence<1>{}),
                 make_tuple(Sequence<0>{}, Sequence<1>{}));
  
             return transform_tensor_descriptor(
                 b_grid_desc_kpad_n,
                 make_tuple(make_unmerge_transform(make_tuple(K0Pad, K1Value)),
                            make_right_pad_transform(N, NPad - N)),
                 make_tuple(Sequence<0>{}, Sequence<1>{}),
                 make_tuple(Sequence<0, 2>{}, Sequence<1>{}));
         }
  
         else if constexpr(GemmSpec == tensor_operation::device::GemmSpecialization::MNPadding)
         {
             return transform_tensor_descriptor(
                 b_grid_desc_k_n,
                 make_tuple(make_unmerge_transform(make_tuple(K0, K1Value)),
                            make_right_pad_transform(N, NPad - N)),
                 make_tuple(Sequence<0>{}, Sequence<1>{}),
                 make_tuple(Sequence<0, 2>{}, Sequence<1>{}));
         }
         else
         {
             return transform_tensor_descriptor(
                 b_grid_desc_k_n,
                 make_tuple(make_unmerge_transform(make_tuple(K0, K1Value)),
                            make_pass_through_transform(N)),
                 make_tuple(Sequence<0>{}, Sequence<1>{}),
                 make_tuple(Sequence<0, 2>{}, Sequence<1>{}));
         }
     }
  
     __device__ static auto
     MakeCGridDescriptor_M_N(index_t M, index_t MPad, index_t N, index_t NPad, index_t StrideC)
     {
         const auto c_grid_desc_m_n = [&]() {
             if constexpr(is_same<tensor_layout::gemm::RowMajor, CLayout>::value)
             {
                 return make_naive_tensor_descriptor(make_tuple(M, N), make_tuple(StrideC, I1));
             }
             else if constexpr(is_same<tensor_layout::gemm::ColumnMajor, CLayout>::value)
             {
                 return make_naive_tensor_descriptor(make_tuple(M, N), make_tuple(I1, StrideC));
             }
         }();
  
         if constexpr(GemmSpec == tensor_operation::device::GemmSpecialization::MNPadding ||
                      GemmSpec == tensor_operation::device::GemmSpecialization::MNKPadding)
         {
             return transform_tensor_descriptor(c_grid_desc_m_n,
                                                make_tuple(make_right_pad_transform(M, MPad - M),
                                                           make_right_pad_transform(N, NPad - N)),
                                                make_tuple(Sequence<0>{}, Sequence<1>{}),
                                                make_tuple(Sequence<0>{}, Sequence<1>{}));
         }
         else
         {
  
             return transform_tensor_descriptor(
                 c_grid_desc_m_n,
                 make_tuple(make_pass_through_transform(M), make_pass_through_transform(N)),
                 make_tuple(Sequence<0>{}, Sequence<1>{}),
                 make_tuple(Sequence<0>{}, Sequence<1>{}));
         }
     }
  
     IS_VALID_COMPILATION_PARAMETER_IMPL(FloatC)
  
     __host__ static constexpr bool CheckValidity(const Problem& problem)
     {
         static_assert(is_known_at_compile_time<remove_cv_t<decltype(K1)>>::value,
                       "wrong! K1 need to be known at compile-time");
  
         static_assert((MPerBlock % (MPerXdl * MXdlPerWave) == 0) &&
                           (NPerBlock % (NXdlPerWave * NPerXdl)) == 0,
                       "Invalid tuning param!");
  
         if constexpr(!(GemmSpec == tensor_operation::device::GemmSpecialization::MPadding ||
                        GemmSpec == tensor_operation::device::GemmSpecialization::MNPadding ||
                        GemmSpec == tensor_operation::device::GemmSpecialization::MKPadding ||
                        GemmSpec == tensor_operation::device::GemmSpecialization::MNKPadding))
         {
             if(!(problem.M % MPerBlock == 0))
             {
                 return false;
             }
         }
  
         if constexpr(!(GemmSpec == tensor_operation::device::GemmSpecialization::NPadding ||
                        GemmSpec == tensor_operation::device::GemmSpecialization::MNPadding ||
                        GemmSpec == tensor_operation::device::GemmSpecialization::NKPadding ||
                        GemmSpec == tensor_operation::device::GemmSpecialization::MNKPadding))
         {
             if(!(problem.N % NPerBlock == 0))
             {
                 return false;
             }
         }
  
         if constexpr(!(GemmSpec == tensor_operation::device::GemmSpecialization::KPadding ||
                        GemmSpec == tensor_operation::device::GemmSpecialization::MKPadding ||
                        GemmSpec == tensor_operation::device::GemmSpecialization::NKPadding ||
                        GemmSpec == tensor_operation::device::GemmSpecialization::MNKPadding))
         {
             if(!(problem.K0 % K0PerBlock == 0))
             {
                 return false;
             }
         }
  
         if constexpr(is_same<tensor_layout::gemm::RowMajor, ALayout>::value)
         {
             if(problem.K % ABlockTransferSrcScalarPerVector != 0)
             {
                 return false;
             }
         }
         else
         {
             if(problem.M % ABlockTransferSrcScalarPerVector != 0)
             {
                 return false;
             }
         }
  
         if constexpr(is_same<tensor_layout::gemm::RowMajor, BLayout>::value)
         {
             if(problem.N % BBlockTransferSrcScalarPerVector != 0)
             {
                 return false;
             }
         }
         else
         {
             if(problem.K % BBlockTransferSrcScalarPerVector != 0)
             {
                 return false;
             }
         }
  
         // check gridwise gemm pipeline
         const auto num_k_loop = math::integer_divide_ceil(problem.K0, K0PerBlock);
  
         if(!GridwiseGemmPipe::IsSupported(num_k_loop))
         {
             return false;
         }
  
         // TODO: also check validity of all components (blockwise-copy, threadwise-copy, etc)
         return true;
     }
 };
  
 } // namespace ck