add some documentation and 2d block scale example

This commit is contained in:
Sami Remes
2025-10-31 20:13:43 +00:00
parent bcccafee40
commit fe92102baf
5 changed files with 507 additions and 17 deletions

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@@ -8,6 +8,9 @@ list(APPEND EXAMPLE_GEMM_COMPILE_OPTIONS -mllvm -enable-noalias-to-md-conversion
if(GPU_TARGETS MATCHES "gfx94" OR GPU_TARGETS MATCHES "gfx95")
add_executable(tile_example_gemm_quant_basic EXCLUDE_FROM_ALL gemm_quant_basic.cpp)
target_compile_options(tile_example_gemm_quant_basic PRIVATE ${EXAMPLE_GEMM_COMPILE_OPTIONS})
add_executable(tile_example_gemm_quant_2d_block EXCLUDE_FROM_ALL gemm_quant_2d_block.cpp)
target_compile_options(tile_example_gemm_quant_2d_block PRIVATE ${EXAMPLE_GEMM_COMPILE_OPTIONS})
else()
message(DEBUG "Skipping ck_tile quant gemm tests for current target")
endif()

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@@ -0,0 +1,442 @@
// SPDX-License-Identifier: MIT
// Copyright (c) 2025, Advanced Micro Devices, Inc. All rights reserved.
// This example demonstrates 2D block scale quantization (N×K) for BQuant
// using non-preshuffled configuration.
// NOTE: Once more 2d support is ready, we can migrate all 2d quant types to this example
// This is currently done separately to avoid too verbose dispatching.
#include <cstring>
#include <iostream>
#include <ostream>
#include <stdexcept>
#include <string>
#include <tuple>
#include "ck_tile/core/config.hpp"
#include "ck_tile/host.hpp"
#include "gemm_utils.hpp"
template <typename GemmConfig,
typename TypeConfig,
typename ALayout,
typename BLayout,
typename CLayout,
typename QuantGroupSize,
ck_tile::QuantType QuantMode,
typename CDEElementWise>
float gemm_calc_quant(const ck_tile::QuantGemmHostArgs& args, const ck_tile::stream_config& s)
{
static_assert(std::is_same_v<CLayout, ck_tile::tensor_layout::gemm::RowMajor>);
using ComputeDataType = std::conditional_t<QuantMode == ck_tile::QuantType::AQuantGrouped ||
QuantMode == ck_tile::QuantType::RowColQuant,
typename TypeConfig::BDataType,
typename TypeConfig::ADataType>;
using GemmShape = ck_tile::TileGemmShape<
ck_tile::sequence<GemmConfig::M_Tile, GemmConfig::N_Tile, GemmConfig::K_Tile>,
ck_tile::sequence<GemmConfig::M_Warp, GemmConfig::N_Warp, GemmConfig::K_Warp>,
ck_tile::
sequence<GemmConfig::M_Warp_Tile, GemmConfig::N_Warp_Tile, GemmConfig::K_Warp_Tile>>;
using TilePartitioner = ck_tile::GemmTile1DPartitioner<GemmShape>;
using GemmTraits = ck_tile::TileGemmQuantTraits<GemmConfig::kPadM,
GemmConfig::kPadN,
GemmConfig::kPadK,
GemmConfig::PreshuffleQuant,
GemmConfig::PreshuffleB,
ALayout,
BLayout,
CLayout,
QuantMode,
ALayout, // for AQLayout
BLayout, // for BQLayout
false,
GemmConfig::DoubleSmemBuffer>;
using GemmPipelineProblem = ck_tile::GemmPipelineProblemBase<typename TypeConfig::ADataType,
typename TypeConfig::BDataType,
typename TypeConfig::AccDataType,
GemmShape,
GemmTraits,
ComputeDataType>;
// This example only supports BQuant (no AQuant)
// For non-preshuffled BQuant, use BaseBQuantGemmPipelineAgBgCrCompV3
using BaseGemmPipeline = std::conditional_t<
GemmConfig::PreshuffleB == true,
ck_tile::BaseWeightPreshufflePipelineAGmemBGmemCRegV2<GemmPipelineProblem>,
ck_tile::BaseBQuantGemmPipelineAgBgCrCompV3<GemmPipelineProblem>>;
const ck_tile::index_t K_split =
(args.K + GemmConfig::K_Tile - 1) / GemmConfig::K_Tile * GemmConfig::K_Tile;
const ck_tile::index_t num_loop = TilePartitioner::GetLoopNum(K_split);
const bool has_hot_loop = BaseGemmPipeline::BlockHasHotloop(num_loop);
const ck_tile::TailNumber tail_num = BaseGemmPipeline::GetBlockLoopTailNum(num_loop);
const auto Run = [&](const auto has_hot_loop_, const auto tail_number_) {
constexpr bool has_hot_loop_v = has_hot_loop_.value;
constexpr auto tail_number_v = tail_number_.value;
constexpr bool transpose_c = false;
// row-col and tensor quants use the regular pipeline, A/B quants use their own
using PipelineProblem = std::conditional_t<
QuantMode == ck_tile::QuantType::RowColQuant ||
QuantMode == ck_tile::QuantType::TensorQuant,
ck_tile::GemmRowColTensorQuantPipelineProblem<typename TypeConfig::ADataType,
typename TypeConfig::BDataType,
typename TypeConfig::AccDataType,
typename TypeConfig::AccDataType,
GemmShape,
GemmTraits,
transpose_c,
ComputeDataType,
GemmConfig::Scheduler,
has_hot_loop_v,
tail_number_v>,
std::conditional_t<QuantMode == ck_tile::QuantType::AQuantGrouped,
ck_tile::GemmAQuantPipelineProblem<typename TypeConfig::ADataType,
typename TypeConfig::QDataType,
typename TypeConfig::BDataType,
typename TypeConfig::AccDataType,
GemmShape,
GemmTraits,
QuantGroupSize,
transpose_c,
ComputeDataType,
GemmConfig::Scheduler,
has_hot_loop_v,
tail_number_v>,
ck_tile::GemmBQuantPipelineProblem<typename TypeConfig::ADataType,
typename TypeConfig::BDataType,
typename TypeConfig::QDataType,
typename TypeConfig::AccDataType,
GemmShape,
GemmTraits,
QuantGroupSize,
ComputeDataType,
GemmConfig::Scheduler,
has_hot_loop_v,
tail_number_v>>>;
using GemmPipeline = std::conditional_t<
QuantMode == ck_tile::QuantType::RowColQuant ||
QuantMode == ck_tile::QuantType::TensorQuant,
ck_tile::GemmPipelineAgBgCrCompV3<PipelineProblem>,
std::conditional_t<
QuantMode == ck_tile::QuantType::AQuantGrouped,
ck_tile::AQuantGemmPipelineAgBgCrMem<PipelineProblem>, // memory pipeline hardcoded
// for aquant
std::conditional_t<GemmConfig::PreshuffleB == true,
ck_tile::WPQuantBPipelineAgBgCrV2<PipelineProblem>,
ck_tile::BQuantGemmPipelineAgBgCrCompV3<PipelineProblem>>>>;
using GemmEpilogue = ck_tile::CShuffleEpilogue<
ck_tile::CShuffleEpilogueProblem<typename TypeConfig::ADataType,
typename TypeConfig::BDataType,
ck_tile::tuple<>,
typename TypeConfig::AccDataType,
typename TypeConfig::CDataType,
ck_tile::tuple<>,
CLayout,
CDEElementWise,
TilePartitioner::MPerBlock,
TilePartitioner::NPerBlock,
GemmConfig::M_Warp,
GemmConfig::N_Warp,
GemmConfig::M_Warp_Tile,
GemmConfig::N_Warp_Tile,
GemmConfig::K_Warp_Tile,
transpose_c,
ck_tile::memory_operation_enum::set,
1,
false,
1,
GemmConfig::TiledMMAPermuteN>>;
using Kernel =
ck_tile::QuantGemmKernel<TilePartitioner, GemmPipeline, GemmEpilogue, QuantMode>;
auto kargs = Kernel::MakeKernelArgs(args);
const dim3 grids = Kernel::GridSize(args.M, args.N, args.k_batch);
const dim3 blocks = Kernel::BlockSize();
if(args.k_batch != 1)
{
throw std::runtime_error("split-k is not supported yet!");
}
if(!Kernel::IsSupportedArgument(kargs))
{
throw std::runtime_error("Wrong! Arguments not supported! Skipping gemm!\n");
}
if(s.log_level_ > 0)
{
std::cout << "Launching kernel with args: " << Kernel::GetName() << '\n'
<< "shape: " << GemmShape::GetName() << '\n'
<< "problem: " << PipelineProblem::GetName() << '\n'
<< "pipeline: " << GemmPipeline::GetName() << '\n'
<< "grid: {" << grids.x << ", " << grids.y << ", " << grids.z << "}"
<< ", blocks: {" << blocks.x << ", " << blocks.y << ", " << blocks.z << "}"
<< std::endl;
}
float ave_time = 0;
if(s.flush_cache_)
{
std::cout << "Flushing cache..." << std::endl;
ck_tile::HostTensor<typename TypeConfig::ADataType> a_m(ck_tile::host_tensor_descriptor(
args.M, args.K, args.stride_A, is_row_major(ALayout{})));
ck_tile::HostTensor<typename TypeConfig::BDataType> b_n(ck_tile::host_tensor_descriptor(
args.K, args.N, args.stride_B, is_row_major(BLayout{})));
auto size_a_buffer = a_m.get_element_space_size_in_bytes();
auto size_b_buffer = b_n.get_element_space_size_in_bytes();
ck_tile::RotatingMemWrapper<typename TypeConfig::ADataType,
typename TypeConfig::BDataType>
rotating_mem(
kargs.a_ptr, kargs.b_ptr, s.rotating_count_, size_a_buffer, size_b_buffer);
rotating_mem.Print();
auto run_flush_cache = [&]() {
// flush icache
ck_tile::flush_icache();
// rotating mem
rotating_mem.Next();
// clear c mem
if(args.k_batch > 1)
hipGetErrorString(
hipMemsetAsync(args.c_ptr,
0,
args.M * args.N * sizeof(typename TypeConfig::CDataType),
s.stream_id_));
};
ave_time = ck_tile::launch_kernel_time_mask(
s,
run_flush_cache,
ck_tile::make_kernel<GemmConfig::kBlockPerCu>(Kernel{}, grids, blocks, 0, kargs));
}
else
{
ave_time = ck_tile::launch_kernel(
s,
ck_tile::make_kernel<GemmConfig::kBlockPerCu>(Kernel{}, grids, blocks, 0, kargs));
}
return ave_time;
};
return BaseGemmPipeline::TailHandler(Run, has_hot_loop, tail_num);
}
#include "run_gemm_quant_example.inc"
template <typename GemmConfig,
typename TypeConfig,
typename QuantGroupSize,
ck_tile::QuantType QuantMode>
int run_gemm_example_prec_type(std::string a_layout, std::string b_layout, int argc, char* argv[])
{
using Row = ck_tile::tensor_layout::gemm::RowMajor;
using Col = ck_tile::tensor_layout::gemm::ColumnMajor;
if((QuantMode == ck_tile::QuantType::AQuantGrouped ||
QuantMode == ck_tile::QuantType::RowColQuant) &&
GemmConfig::PreshuffleB)
{
throw std::runtime_error(
"Preshuffling weight matrix is not supported for AQuant or RowColQuant");
}
if constexpr(std::is_same_v<typename TypeConfig::ADataType, ck_tile::pk_int4_t> ||
std::is_same_v<typename TypeConfig::ADataType, ck_tile::fp8_t> ||
std::is_same_v<typename TypeConfig::ADataType, ck_tile::bf8_t>)
{
if(a_layout == "R" && b_layout == "C")
{
return run_gemm_example_with_layouts<GemmConfig, TypeConfig, QuantGroupSize, QuantMode>(
argc, argv, Row{}, Row{}, Col{}, Col{}, Row{});
}
else
{
throw std::runtime_error("Unsupported memory layout for the input matrices!");
}
}
else
{
throw std::runtime_error("Unsupported data type for A.");
}
return 0;
}
// Forward declaration for dispatch function
template <template <typename PreType> typename GemmConfig, typename QuantGroupSize>
int dispatch_by_data_type(const std::string& data_type,
const std::string& quant_mode,
const std::string& a_layout,
const std::string& b_layout,
int argc,
char* argv[]);
// Helper function to parse group size string "MxNxK"
std::tuple<int, int, int> parse_group_size(const std::string& group_size_str)
{
int m = 1, n = 1, k = 128;
size_t first_x = group_size_str.find('x');
if(first_x == std::string::npos)
{
// Single number provided, assume it's the K dimension
k = std::stoi(group_size_str);
return {1, 1, k};
}
size_t second_x = group_size_str.find('x', first_x + 1);
if(second_x == std::string::npos)
{
throw std::runtime_error("Invalid group_size format! Expected MxNxK (e.g., 1x32x128)");
}
m = std::stoi(group_size_str.substr(0, first_x));
n = std::stoi(group_size_str.substr(first_x + 1, second_x - first_x - 1));
k = std::stoi(group_size_str.substr(second_x + 1));
return {m, n, k};
}
template <template <typename PreType> typename GemmConfig>
int run_gemm_example(int argc, char* argv[])
{
auto [result, arg_parser] = create_args(argc, argv);
if(!result)
return -1;
std::string data_type = arg_parser.get_str("prec");
std::string a_layout = arg_parser.get_str("a_layout");
std::string b_layout = arg_parser.get_str("b_layout");
std::string quant_mode = arg_parser.get_str("quant_mode");
std::string group_size_str = arg_parser.get_str("group_size");
auto [m_group, n_group, k_group] = parse_group_size(group_size_str);
// Dispatch based on group size (M, N, K)
auto dispatch_by_group_size = [&]<int M, int N, int K>() {
using QuantGroupSize = ck_tile::QuantGroupShape<ck_tile::sequence<M, N, K>>;
return dispatch_by_data_type<GemmConfig, QuantGroupSize>(
data_type, quant_mode, a_layout, b_layout, argc, argv);
};
// Dispatch for supported group sizes
// Note: This example uses non-preshuffled BQuant which supports both K-only and N×K quantization
if(m_group == 1 && n_group == 1 && k_group == 64)
{
return dispatch_by_group_size.template operator()<1, 1, 64>();
}
else if(m_group == 1 && n_group == 1 && k_group == 128)
{
return dispatch_by_group_size.template operator()<1, 1, 128>();
}
else if(m_group == 1 && n_group == 8 && k_group == 128)
{
return dispatch_by_group_size.template operator()<1, 8, 128>();
}
else if(m_group == 1 && n_group == 32 && k_group == 128)
{
return dispatch_by_group_size.template operator()<1, 32, 128>();
}
else if(m_group == 1 && n_group == 64 && k_group == 128)
{
return dispatch_by_group_size.template operator()<1, 64, 128>();
}
else if(m_group == 1 && n_group == 128 && k_group == 128)
{
return dispatch_by_group_size.template operator()<1, 128, 128>();
}
else
{
throw std::runtime_error(
"Unsupported group size! Supported values are:\n"
" K-only quantization: 1x1x64, 1x1x128\n"
" N×K quantization (BQuant only): 1x8x128, 1x32x128, 1x64x128, 1x128x128\n"
"\nNote: This example uses non-preshuffled BQuant for 2D block scale support");
}
}
template <template <typename PreType> typename GemmConfig, typename QuantGroupSize>
int dispatch_by_data_type(const std::string& data_type,
const std::string& quant_mode,
const std::string& a_layout,
const std::string& b_layout,
int argc,
char* argv[])
{
// This example ONLY supports BQuant for 2D block scale quantization
if(quant_mode != "bquant")
{
throw std::runtime_error(
"This example only supports BQuant! Use --quant_mode=bquant");
}
if(data_type == "fp8")
{
using TypeConfig =
decltype(GemmQuantTypeConfig<ck_tile::fp8_t, ck_tile::fp8_t, ck_tile::half_t, float>{});
return run_gemm_example_prec_type<GemmConfig<ck_tile::fp8_t>,
TypeConfig,
QuantGroupSize,
ck_tile::QuantType::BQuantGrouped>(
a_layout, b_layout, argc, argv);
}
else if(data_type == "bf8")
{
using TypeConfig =
decltype(GemmQuantTypeConfig<ck_tile::bf8_t, ck_tile::bf8_t, ck_tile::half_t, float>{});
return run_gemm_example_prec_type<GemmConfig<ck_tile::bf8_t>,
TypeConfig,
QuantGroupSize,
ck_tile::QuantType::BQuantGrouped>(
a_layout, b_layout, argc, argv);
}
else if(data_type == "fp8i4")
{
using TypeConfig = decltype(GemmQuantTypeConfig<ck_tile::fp8_t,
ck_tile::pk_int4_t,
ck_tile::half_t,
ck_tile::fp8_t>{});
return run_gemm_example_prec_type<GemmConfig<ck_tile::fp8_t>,
TypeConfig,
QuantGroupSize,
ck_tile::QuantType::BQuantGrouped>(
a_layout, b_layout, argc, argv);
}
else if(data_type == "bf8i4")
{
using TypeConfig = decltype(GemmQuantTypeConfig<ck_tile::bf8_t,
ck_tile::pk_int4_t,
ck_tile::half_t,
ck_tile::bf8_t>{});
return run_gemm_example_prec_type<GemmConfig<ck_tile::bf8_t>,
TypeConfig,
QuantGroupSize,
ck_tile::QuantType::BQuantGrouped>(
a_layout, b_layout, argc, argv);
}
else
{
throw std::runtime_error("Unsupported data type for this operation !!!");
}
}
int main(int argc, char* argv[])
{
// Use non-preshuffled GemmConfig for 2D block scale support
return !run_gemm_example<GemmConfigBQuantPrefill>(argc, argv);
}

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@@ -193,6 +193,22 @@ struct GemmConfigPreshuffleB_Bquant_prefill : public GemmConfigBase
static constexpr bool TiledMMAPermuteN = N_Repeat % 2 == 0;
};
template <typename PrecType>
struct GemmConfigBQuantPrefill : public GemmConfigBase
{
static constexpr ck_tile::index_t M_Tile = 128;
static constexpr ck_tile::index_t N_Tile = 128;
static constexpr ck_tile::index_t K_Tile = 128 / sizeof(PrecType);
static constexpr ck_tile::index_t M_Warp = 1;
static constexpr ck_tile::index_t N_Warp = 4;
static constexpr ck_tile::index_t K_Warp = 1;
static constexpr ck_tile::index_t M_Warp_Tile = 16;
static constexpr ck_tile::index_t N_Warp_Tile = 16;
static constexpr ck_tile::index_t K_Warp_Tile = get_k_warp_tile<PrecType, M_Warp_Tile>();
};
template <typename ADataType_,
typename BDataType_ = ADataType_,
typename CDataType_ = ADataType_,
@@ -288,7 +304,8 @@ auto create_args(int argc, char* argv[])
.insert("init", "0", "0:random, 1:linear, 2:constant(1)")
.insert("flush_cache", "true", "flush cache before running the kernel, defaults to true")
.insert("rotating_count", "1000", "rotating count, defaults to 1")
.insert("quant_mode", "bquant", "Choose aquant (default), bquant, tensor or rowcol");
.insert("quant_mode", "bquant", "Choose aquant (default), bquant, tensor or rowcol")
.insert("group_size", "1x1x128", "Quantization group size as MxNxK, e.g., 1x1x128, 1x32x128, 1x64x128");
bool result = arg_parser.parse(argc, argv);
return std::make_tuple(result, arg_parser);

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@@ -33,9 +33,9 @@ struct GemmBQuantPipelineAgBgCrImplBase : public GemmPipelineAgBgCrImplBase<Prob
static_assert(KPerBlockBQ >= 1, "KPerBlock must be >= QuantGroupSize");
static_assert(NPerBlock % QuantGroupSize::kN == 0,
"NPerBlock must be a multiple of QuantGroupSize");
"NPerBlock must be a multiple of QuantGroupSize::kN");
static_assert(KPerBlock % QuantGroupSize::kK == 0,
"KPerBlock must be a multiple of QuantGroupSize");
"KPerBlock must be a multiple of QuantGroupSize::kK");
// Create DRAM tile window for BQ
template <typename BQDramBlockWindowTmp>

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@@ -171,7 +171,7 @@ template <typename BlockGemmShape,
index_t BlockSize,
index_t YPerTile,
index_t XPerTile,
index_t YPerQ>
index_t XPerQ>
struct tile_distribution_encoding_pattern_bq : public tile_distribution_encoding_pattern
{
static constexpr index_t warp_size = get_warp_size();
@@ -186,17 +186,42 @@ struct tile_distribution_encoding_pattern_bq : public tile_distribution_encoding
static_assert(num_warps == MWarps * NWarps * KWarps);
static_assert(KWarps == 1);
/// @brief Creates a 2D tile distribution for BQ (B-matrix quantization scales)
///
/// This function determines the optimal thread distribution pattern for loading and applying
/// quantization scales to the B matrix based on the quantization group size (XPerQ) relative
/// to warp dimensions.
///
/// Three distinct distribution patterns are handled:
///
/// 1. Fine-grained quantization (XPerQ < WarpGemm::kN):
/// - Multiple quantization groups exist within a single warp's N-dimension
/// - Each warp processes multiple scales (WarpGemm::kN / XPerQ scales per warp)
/// - Distribution includes explicit replication factor (XR = XPerQ) for scale broadcast
/// - Example: XPerQ=8, WarpGemm::kN=16, NWarps=4 → 2 scales per warp
///
/// 2. Medium-grained quantization (WarpGemm::kN <= XPerQ <= WarpGemm::kN * NWarps):
/// - Each warp handles exactly one quantization scale
/// - Scales are distributed across warps with replication factor XR = XPerQ / WarpGemm::kN
/// - Example: XPerQ=64, WarpGemm::kN=16, NWarps=4 → 1 scale per warp, XR=4
///
/// 3. Coarse-grained quantization (XPerQ > WarpGemm::kN * NWarps):
/// - Quantization group spans multiple warps
/// - All warps share the same scale value
/// - Example: XPerQ=128, WarpGemm::kN=16, NWarps=4 → all warps use same scale
///
/// @return A static tile distribution encoding for the BQ scale tensor
CK_TILE_HOST_DEVICE static constexpr auto make_2d_static_tile_distribution()
{
if constexpr(YPerQ < WarpGemm::kN)
if constexpr(XPerQ < WarpGemm::kN)
{
// each row of B has independent scale
constexpr index_t Y = YPerTile;
constexpr index_t YR = 1;
constexpr index_t X0 = NIterPerWarp;
constexpr index_t X1 = NWarps;
constexpr index_t X2 = WarpGemm::kN / YPerQ;
constexpr index_t XR = YPerQ;
// Case 1: Fine-grained - multiple quantization scales within a single warp
constexpr index_t Y = YPerTile; // Full Y dimension of tile
constexpr index_t YR = 1; // No Y replication needed
constexpr index_t X0 = NIterPerWarp; // Iterations per warp in N-dim
constexpr index_t X1 = NWarps; // Number of warps in N-dim
constexpr index_t X2 = WarpGemm::kN / XPerQ; // Number of scales per warp
constexpr index_t XR = XPerQ; // Elements per quantization group
static_assert(X0 * X1 * X2 == XPerTile, "X0, X1, X2 must cover the blocktile along X.");
@@ -208,11 +233,12 @@ struct tile_distribution_encoding_pattern_bq : public tile_distribution_encoding
sequence<2, 1>,
sequence<0, 0>>{});
}
else if constexpr(YPerQ <= WarpGemm::kN * NWarps)
else if constexpr(XPerQ <= WarpGemm::kN * NWarps)
{
constexpr auto XR = YPerQ / WarpGemm::kN;
constexpr auto X1 = NWarps / XR;
constexpr auto X0 = XPerTile / X1;
// Case 2: Medium-grained - one quantization scale per warp
constexpr auto XR = XPerQ / WarpGemm::kN; // Scale replication factor
constexpr auto X1 = NWarps / XR; // Warps per unique scale
constexpr auto X0 = XPerTile / X1; // Iterations to cover X dimension
return make_static_tile_distribution(
tile_distribution_encoding<sequence<MWarps, XR, get_warp_size()>,
tuple<sequence<YPerTile>, sequence<X0, X1>>,
@@ -221,8 +247,10 @@ struct tile_distribution_encoding_pattern_bq : public tile_distribution_encoding
sequence<2, 1>,
sequence<0, 0>>{});
}
else // YPerQ > WarpGemm::kN * NWarps
else // XPerQ > WarpGemm::kN * NWarps
{
// Case 3: Coarse-grained - quantization group spans all warps
// All warps in N-dimension share the same quantization scale
return make_static_tile_distribution(
tile_distribution_encoding<sequence<MWarps, NWarps, get_warp_size()>,
tuple<sequence<YPerTile>, sequence<XPerTile>>,