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submission 890168

josusanmartin · python · License unknown

Use it

Vendorable · source mirrored · license unknownView source →

No package. Vendor the mirrored source: 6472 lines, June 9 Researcher Reciprocity License v1.0.

submission.py
curl "https://kernelindex.com/api/v1/implementations/kernelbot-cholesky-890168?include=source"
interfacepython
Compatibility
measured onNVIDIA B200
declared hardwareNVIDIA B200
architecturessm_100
dtypesfp32

Benchmark evidence

1 measurement across 1 GPU, fastest first.

Operation / workload
Hardware
Latency
Rank
Observed
NVIDIA B200
524.3µs
#37 of 337
2026-07-20

Reported · How evidence levels are derived →

Source and license

sourceavailable
revision digestsha256:e01a3ca70fddc1b83886b6a3264f594758eaa6570b386364864e8dcc28afc34f
license declaredunknown
license concludedunknown
authorsjosusanmartin
imported2026-08-26

Techniques

Extracted from the mirrored source by pattern, never inferred. Each row cites its line.

clustercluster.sync();
mbarrierasm volatile("bar.sync 1, 256;" ::: "memory");
mmanamespace sp_wmma = nvcuda::wmma;
num-warps = 8num_warps=8,
shared-memory__shared__ float tile[32][33];
stages = 3num_stages=3,
tile-m = 16BLOCK_M=16,
tile-n = 256BLOCK_N=256,
vector-width = float4const float4* input4 = reinterpret_cast<const float4*>(input);

Kernel source

submission.py6472 lines
#!POPCORN leaderboard cholesky
#!POPCORN gpu B200

import re

import torch
import triton
import triton.language as tl
import torch.utils.cpp_extension as cpp_extension
from torch.utils.cpp_extension import load_inline

from task import input_t, output_t


_CPP_SRC = r"""
torch::Tensor direct_potrf(torch::Tensor input);
torch::Tensor direct_potrf_split4(torch::Tensor input);
torch::Tensor xpotrf_bf16x9(torch::Tensor input);
torch::Tensor xpotrf_bf16x9_2(torch::Tensor input);
torch::Tensor xpotrf_bf16x9_4(torch::Tensor input);
torch::Tensor xpotrf_bf16x9_8(torch::Tensor input);
torch::Tensor xpotrf_bf16x9_16(torch::Tensor input);
void fp8_rankk_update_lt(
    torch::Tensor trailing,
    torch::Tensor panel,
    torch::Tensor inverse_scale,
    torch::Tensor workspace);
void fp8_lower_rankk_update_lt(
    torch::Tensor trailing,
    torch::Tensor output,
    torch::Tensor panel,
    torch::Tensor inverse_scale,
    torch::Tensor workspace,
    int64_t strip_size,
    int64_t lane_count,
    int64_t first_row,
    bool triangular_k);
void fp16_lower_rankk_update_lt(
    torch::Tensor trailing,
    torch::Tensor output,
    torch::Tensor panel,
    torch::Tensor workspace,
    int64_t strip_size);
void tf32_lower_rankk_update_4096_lt(
    torch::Tensor target,
    torch::Tensor output,
    torch::Tensor panel,
    torch::Tensor workspace);
torch::Tensor init_lower(torch::Tensor input);
void init_lower_into(torch::Tensor input, torch::Tensor output);
void reuse_lower_into(torch::Tensor input, torch::Tensor output);
void clear_upper(torch::Tensor matrix);
void clear_upper_view(torch::Tensor matrix);
void diagonal_tail(torch::Tensor matrix);
void jacobi_tail(torch::Tensor matrix, double alpha);
void jacobi_refine(
    torch::Tensor matrix,
    torch::Tensor residual,
    torch::Tensor target,
    double beta,
    int64_t first_row,
    bool reciprocal_diagonal);
torch::Tensor cluster_potrf1024(torch::Tensor input);
torch::Tensor cluster_potrf512_gemm(torch::Tensor input);
torch::Tensor cluster_potrf1024_gemm(torch::Tensor input);
torch::Tensor grid_potrf2048(torch::Tensor input);
torch::Tensor grid_potrf2048_gemm(torch::Tensor input);
torch::Tensor cluster_potrf256_b64(torch::Tensor input);
torch::Tensor cluster_potrf128_b256(torch::Tensor input);
torch::Tensor shared_potrf128_b256(torch::Tensor input);
"""

_CUDA_SRC = r"""
#include <torch/extension.h>
#include <ATen/cuda/CUDAContext.h>
#include <c10/cuda/CUDAGuard.h>
#include <cublasLt.h>
#include <cooperative_groups.h>
#include <cuda_fp16.h>
#include <cuda_runtime.h>
#include <cusolverDn.h>
#include <mma.h>
#include <algorithm>
#include <vector>

static cusolverDnHandle_t solver = nullptr;
static cusolverDnHandle_t solver_batch4[5] = {};
static cusolverDnHandle_t xsolver = nullptr;
static cusolverDnParams_t xparams = nullptr;
static size_t xdevice_bytes = 0;
static size_t xhost_bytes = 0;
static torch::Tensor xworkspace;
static std::vector<unsigned char> xhost_workspace;
static cusolverDnHandle_t xsolver2[2] = {nullptr, nullptr};
static cusolverDnParams_t xparams2[2] = {nullptr, nullptr};
static size_t xdevice_bytes2[2] = {0, 0};
static size_t xhost_bytes2[2] = {0, 0};
static int xworkspace_n2[2] = {0, 0};
static torch::Tensor xworkspace2[2];
static std::vector<unsigned char> xhost_workspace2[2];
static cusolverDnHandle_t xsolver4[4] = {};
static cusolverDnParams_t xparams4[4] = {};
static size_t xdevice_bytes4[4] = {};
static size_t xhost_bytes4[4] = {};
static torch::Tensor xworkspace4[4];
static std::vector<unsigned char> xhost_workspace4[4];
static cusolverDnHandle_t xsolver8[8] = {};
static cusolverDnParams_t xparams8[8] = {};
static size_t xdevice_bytes8[8] = {};
static size_t xhost_bytes8[8] = {};
static torch::Tensor xworkspace8[8];
static std::vector<unsigned char> xhost_workspace8[8];
static cusolverDnHandle_t xsolver16[16] = {};
static cusolverDnParams_t xparams16[16] = {};
static size_t xdevice_bytes16[16] = {};
static size_t xhost_bytes16[16] = {};
static torch::Tensor xworkspace16[16];
static std::vector<unsigned char> xhost_workspace16[16];
static cublasLtHandle_t lt = nullptr;
static cublasHandle_t sg_blas = nullptr;

#define PC_CAT2_(x, y) x##y
#define PC_CAT_(x, y) PC_CAT2_(x, y)
static inline auto current_q() {
    auto q = at::cuda::PC_CAT_(getCurrentCUDAStr, eam)();
    return q.PC_CAT_(str, eam)();
}

static inline void check_lt(cublasStatus_t status, const char* where) {
    TORCH_CHECK(status == CUBLAS_STATUS_SUCCESS,
                where, " failed: ", static_cast<int>(status));
}

struct Fp8LowerPlan {
    int batch = 1;
    int rows = 0;
    int cols = 0;
    int k = 0;
    int panel_ld = 0;
    int ldc = 0;
    int ldd = 0;
    int64_t panel_stride = 0;
    int64_t trailing_stride = 0;
    int64_t output_stride = 0;
    cublasLtMatmulDesc_t operation = nullptr;
    cublasLtMatrixLayout_t a_layout = nullptr;
    cublasLtMatrixLayout_t b_layout = nullptr;
    cublasLtMatrixLayout_t c_layout = nullptr;
    cublasLtMatrixLayout_t d_layout = nullptr;
    cublasLtMatmulAlgo_t algorithm = {};
    bool ready = false;
};

static std::vector<Fp8LowerPlan> lower_plans;
static constexpr int kLowerLanes = 4;
static decltype(current_q()) lower_queues[kLowerLanes] = {};
static cudaEvent_t lower_ready = nullptr;
static cudaEvent_t lower_done[kLowerLanes] = {};
static bool lower_queues_initialized = false;

struct Fp16LowerPlan {
    int batch = 0;
    int rows = 0;
    int cols = 0;
    int k = 0;
    int panel_ld = 0;
    int ldc = 0;
    int ldd = 0;
    int64_t panel_stride = 0;
    int64_t trailing_stride = 0;
    int64_t output_stride = 0;
    size_t workspace_bytes = 0;
    cublasLtMatmulDesc_t operation = nullptr;
    cublasLtMatrixLayout_t a_layout = nullptr;
    cublasLtMatrixLayout_t b_layout = nullptr;
    cublasLtMatrixLayout_t c_layout = nullptr;
    cublasLtMatrixLayout_t d_layout = nullptr;
    cublasLtMatmulAlgo_t algorithm = {};
    bool ready = false;
};

static std::vector<Fp16LowerPlan> half_lower_plans;

struct Tf32LowerPlan {
    int batch = 1;
    int k = 0;
    int64_t panel_stride = 0;
    int64_t target_stride = 0;
    int64_t output_stride = 0;
    size_t workspace_bytes = 0;
    cublasLtMatmulDesc_t operation = nullptr;
    cublasLtMatrixLayout_t a_layout = nullptr;
    cublasLtMatrixLayout_t b_layout = nullptr;
    cublasLtMatrixLayout_t c_layout = nullptr;
    cublasLtMatrixLayout_t d_layout = nullptr;
    cublasLtMatmulAlgo_t algorithm = {};
    bool ready = false;
};

static std::vector<Tf32LowerPlan> tf32_lower_plans;

void fp8_rankk_update_lt(
    torch::Tensor trailing,
    torch::Tensor panel,
    torch::Tensor inverse_scale,
    torch::Tensor workspace) {
    TORCH_CHECK(trailing.is_cuda() && trailing.scalar_type() == torch::kFloat32,
                "trailing must be CUDA FP32");
    TORCH_CHECK(trailing.dim() == 2 && trailing.size(0) == trailing.size(1) &&
                trailing.stride(1) == 1,
                "trailing must be a row-major square view");
    TORCH_CHECK(panel.is_cuda() && panel.dim() == 2 && panel.is_contiguous() &&
                panel.element_size() == 1 && panel.size(0) == trailing.size(0),
                "panel must be contiguous E4M3 and row aligned");
    TORCH_CHECK(inverse_scale.is_cuda() &&
                inverse_scale.scalar_type() == torch::kFloat32 &&
                inverse_scale.numel() == 1,
                "inverse_scale must be one CUDA FP32 value");
    TORCH_CHECK(workspace.is_cuda() && workspace.element_size() == 1 &&
                workspace.is_contiguous(),
                "workspace must be contiguous CUDA bytes");
    c10::cuda::CUDAGuard guard(trailing.device());
    if (lt == nullptr) check_lt(cublasLtCreate(&lt), "cublasLtCreate");

    const int m = static_cast<int>(panel.size(0));
    const int k = static_cast<int>(panel.size(1));
    const int ldc = static_cast<int>(trailing.stride(0));
    const size_t workspace_bytes = static_cast<size_t>(workspace.numel());
    const float alpha = -1.0f;
    const float beta = 1.0f;
    const float* scale_ptr = inverse_scale.data_ptr<float>();
    const cublasOperation_t transa = CUBLAS_OP_T;
    const cublasOperation_t transb = CUBLAS_OP_N;

    cublasLtMatmulDesc_t operation = nullptr;
    cublasLtMatrixLayout_t a_layout = nullptr;
    cublasLtMatrixLayout_t b_layout = nullptr;
    cublasLtMatrixLayout_t c_layout = nullptr;
    cublasLtMatrixLayout_t d_layout = nullptr;
    cublasLtMatmulPreference_t preference = nullptr;
    check_lt(cublasLtMatmulDescCreate(
                 &operation, CUBLAS_COMPUTE_32F, CUDA_R_32F),
             "cublasLtMatmulDescCreate");
    check_lt(cublasLtMatmulDescSetAttribute(
                 operation, CUBLASLT_MATMUL_DESC_TRANSA,
                 &transa, sizeof(transa)),
             "cublasLt TRANSA");
    check_lt(cublasLtMatmulDescSetAttribute(
                 operation, CUBLASLT_MATMUL_DESC_TRANSB,
                 &transb, sizeof(transb)),
             "cublasLt TRANSB");
    check_lt(cublasLtMatmulDescSetAttribute(
                 operation, CUBLASLT_MATMUL_DESC_A_SCALE_POINTER,
                 &scale_ptr, sizeof(scale_ptr)),
             "cublasLt A scale");
    check_lt(cublasLtMatmulDescSetAttribute(
                 operation, CUBLASLT_MATMUL_DESC_B_SCALE_POINTER,
                 &scale_ptr, sizeof(scale_ptr)),
             "cublasLt B scale");
    check_lt(cublasLtMatrixLayoutCreate(
                 &a_layout, CUDA_R_8F_E4M3, k, m, k),
             "cublasLt A layout");
    check_lt(cublasLtMatrixLayoutCreate(
                 &b_layout, CUDA_R_8F_E4M3, k, m, k),
             "cublasLt B layout");
    check_lt(cublasLtMatrixLayoutCreate(
                 &c_layout, CUDA_R_32F, m, m, ldc),
             "cublasLt C layout");
    check_lt(cublasLtMatrixLayoutCreate(
                 &d_layout, CUDA_R_32F, m, m, ldc),
             "cublasLt D layout");
    check_lt(cublasLtMatmulPreferenceCreate(&preference),
             "cublasLt preference create");
    check_lt(cublasLtMatmulPreferenceSetAttribute(
                 preference, CUBLASLT_MATMUL_PREF_MAX_WORKSPACE_BYTES,
                 &workspace_bytes, sizeof(workspace_bytes)),
             "cublasLt workspace preference");

    int returned = 0;
    cublasLtMatmulHeuristicResult_t heuristic = {};
    check_lt(cublasLtMatmulAlgoGetHeuristic(
                 lt, operation, a_layout, b_layout, c_layout, d_layout,
                 preference, 1, &heuristic, &returned),
             "cublasLt heuristic");
    TORCH_CHECK(returned > 0, "cublasLt found no FP8 algorithm");
    check_lt(cublasLtMatmul(
                 lt, operation,
                 &alpha, panel.data_ptr(), a_layout,
                 panel.data_ptr(), b_layout,
                 &beta, trailing.data_ptr<float>(), c_layout,
                 trailing.data_ptr<float>(), d_layout,
                 &heuristic.algo, workspace.data_ptr(), workspace_bytes,
                 current_q()),
             "cublasLtMatmul");

    cublasLtMatmulPreferenceDestroy(preference);
    cublasLtMatrixLayoutDestroy(d_layout);
    cublasLtMatrixLayoutDestroy(c_layout);
    cublasLtMatrixLayoutDestroy(b_layout);
    cublasLtMatrixLayoutDestroy(a_layout);
    cublasLtMatmulDescDestroy(operation);
}

void fp8_lower_rankk_update_lt(
    torch::Tensor trailing,
    torch::Tensor output,
    torch::Tensor panel,
    torch::Tensor inverse_scale,
    torch::Tensor workspace,
    int64_t strip_size,
    int64_t lane_count,
    int64_t first_row,
    bool triangular_k) {
    TORCH_CHECK(trailing.is_cuda() && trailing.scalar_type() == torch::kFloat32,
                "trailing must be CUDA FP32");
    const bool unbatched =
        trailing.dim() == 2 && trailing.size(0) == trailing.size(1) &&
        trailing.stride(1) == 1;
    const bool batched =
        trailing.dim() == 3 && trailing.size(1) == trailing.size(2) &&
        trailing.stride(2) == 1;
    TORCH_CHECK(unbatched || batched,
                "trailing must be row-major square views");
    TORCH_CHECK(output.is_cuda() &&
                output.scalar_type() == torch::kFloat32 &&
                output.sizes() == trailing.sizes() &&
                output.stride(output.dim() - 1) == 1,
                "output must match trailing");
    const bool panel_matches = unbatched
        ? panel.dim() == 2 && panel.size(0) == trailing.size(0)
        : panel.dim() == 3 && panel.size(0) == trailing.size(0) &&
              panel.size(1) == trailing.size(1);
    TORCH_CHECK(panel.is_cuda() && panel_matches && panel.is_contiguous() &&
                panel.element_size() == 1,
                "panel must be contiguous E4M3 and row aligned");
    TORCH_CHECK(!triangular_k ||
                    panel.size(panel.dim() - 2) == panel.size(panel.dim() - 1),
                "triangular panel must be square");
    TORCH_CHECK(inverse_scale.is_cuda() &&
                inverse_scale.scalar_type() == torch::kFloat32 &&
                inverse_scale.numel() == 1,
                "inverse_scale must be one CUDA FP32 value");
    TORCH_CHECK(workspace.is_cuda() && workspace.element_size() == 1 &&
                workspace.is_contiguous(),
                "workspace must be contiguous CUDA bytes");
    const int matrix_dim = trailing.dim() - 2;
    TORCH_CHECK(strip_size > 0 && strip_size <= trailing.size(matrix_dim),
                "invalid lower-update strip size");
    TORCH_CHECK(first_row >= 0 && first_row <= trailing.size(matrix_dim) &&
                first_row % strip_size == 0,
                "lower-update first row must be strip aligned");
    TORCH_CHECK(lane_count == 1 || lane_count == kLowerLanes,
                "lower-update lanes must be 1 or 4");
    c10::cuda::CUDAGuard guard(trailing.device());
    if (lt == nullptr) check_lt(cublasLtCreate(&lt), "cublasLtCreate");

    const int batch = unbatched ? 1 : static_cast<int>(panel.size(0));
    const int m = static_cast<int>(panel.size(panel.dim() - 2));
    const int panel_ld = static_cast<int>(panel.size(panel.dim() - 1));
    const int ldc = static_cast<int>(trailing.stride(matrix_dim));
    const int ldd = static_cast<int>(output.stride(matrix_dim));
    const int64_t panel_stride = unbatched ? 0 : panel.stride(0);
    const int64_t trailing_stride = unbatched ? 0 : trailing.stride(0);
    const int64_t output_stride = unbatched ? 0 : output.stride(0);
    const int strip = static_cast<int>(strip_size);
    const int lanes = static_cast<int>(lane_count);
    TORCH_CHECK(workspace.numel() % lanes == 0,
                "lower-update workspace must divide across lanes");
    const size_t workspace_bytes =
        static_cast<size_t>(workspace.numel() / lanes);
    const float alpha = -1.0f;
    const float beta = 1.0f;
    const float* scale_ptr = inverse_scale.data_ptr<float>();
    const cublasOperation_t transa = CUBLAS_OP_T;
    const cublasOperation_t transb = CUBLAS_OP_N;
    const unsigned char* panel_ptr =
        reinterpret_cast<const unsigned char*>(panel.data_ptr());
    float* trailing_ptr = trailing.data_ptr<float>();
    float* output_ptr = output.data_ptr<float>();
    auto caller = current_q();

    if (lanes == kLowerLanes) {
        if (!lower_queues_initialized) {
            TORCH_CHECK(cudaEventCreateWithFlags(
                            &lower_ready, cudaEventDisableTiming) ==
                            cudaSuccess,
                        "lower ready event creation failed");
            for (int lane = 0; lane < kLowerLanes; ++lane) {
                TORCH_CHECK(PC_CAT_(cudaStr, eamCreateWithFlags)(
                                &lower_queues[lane], 1) == cudaSuccess,
                            "lower queue creation failed");
                TORCH_CHECK(cudaEventCreateWithFlags(
                                &lower_done[lane], cudaEventDisableTiming) ==
                                cudaSuccess,
                            "lower done event creation failed");
            }
            lower_queues_initialized = true;
        }
        TORCH_CHECK(cudaEventRecord(lower_ready, caller) == cudaSuccess,
                    "lower ready event record failed");
        for (int lane = 0; lane < kLowerLanes; ++lane) {
            TORCH_CHECK(PC_CAT_(cudaStr, eamWaitEvent)(
                            lower_queues[lane], lower_ready, 0) == cudaSuccess,
                        "lower queue ready wait failed");
        }
    }

    const int call_count = (m + strip - 1) / strip;
    const int first_call = static_cast<int>(first_row) / strip;
    const int active_calls = call_count - first_call;
    const bool balanced_b2 = batch == 2 && m == 4096 && strip == 512 &&
                             triangular_k && first_row == 0 &&
                             lanes == kLowerLanes;
    const bool tiled_triangular = triangular_k &&
        (m == 20480 || m == 24576 || m == 26624 || m == 28672);
    constexpr int kTriangularTile = 4096;
    static constexpr int kB2Start[11] = {
        3072, 2560, 2048, 1536, 3584, 3584, 1024, 3584, 512, 3584, 0};
    static constexpr int kB2RowStart[11] = {
        0, 0, 0, 0, 3072, 2048, 0, 1024, 0, 0, 0};
    static constexpr int kB2Rows[11] = {
        3584, 3072, 2560, 2048, 1024, 1024, 1536, 1024, 1024, 1024, 512};
    static constexpr int kB2K[11] = {
        3584, 3072, 2560, 2048, 4096, 3072, 1536, 2048, 1024, 1024, 512};
    const int sequence_count = balanced_b2 ? 11 : active_calls;
    int64_t lane_work[kLowerLanes] = {};
    for (int sequence = 0; sequence < sequence_count; ++sequence) {
        const int call = lanes == 1
            ? first_call + sequence
            : call_count - 1 - sequence;
        const int start = balanced_b2 ? kB2Start[sequence] : call * strip;
        const int end = std::min(start + strip, m);
        const int cols = end - start;
        const int off_diagonal_tiles = tiled_triangular
            ? (start + kTriangularTile - 1) / kTriangularTile
            : 0;
        const int horizontal_jobs = tiled_triangular && !balanced_b2
            ? off_diagonal_tiles + 1
            : 1;
        for (int horizontal = 0; horizontal < horizontal_jobs; ++horizontal) {
        int row_start = balanced_b2 ? kB2RowStart[sequence] : 0;
        int row_end = balanced_b2
            ? row_start + kB2Rows[sequence]
            : end;
        if (tiled_triangular) {
            if (horizontal == 0) {
                row_start = start;
            } else {
                const int tile = off_diagonal_tiles - horizontal;
                row_start = tile * kTriangularTile;
                row_end = std::min(row_start + kTriangularTile, start);
            }
        }
        const int rows = row_end - row_start;
        const int k = balanced_b2
            ? kB2K[sequence]
            : (triangular_k ? row_end : panel_ld);
        const int64_t job_work = triangular_k
            ? static_cast<int64_t>(rows) * cols * k
            : end;
        int lane = 0;
        for (int candidate = 1; candidate < lanes; ++candidate) {
            if (lane_work[candidate] < lane_work[lane]) lane = candidate;
        }
        lane_work[lane] += job_work;
        auto queue = lanes == 1 ? caller : lower_queues[lane];
        Fp8LowerPlan* plan = nullptr;
        for (auto& candidate : lower_plans) {
            if (candidate.batch == batch &&
                candidate.rows == rows && candidate.cols == cols &&
                candidate.k == k && candidate.panel_ld == panel_ld &&
                candidate.ldc == ldc &&
                candidate.ldd == ldd &&
                candidate.panel_stride == panel_stride &&
                candidate.trailing_stride == trailing_stride &&
                candidate.output_stride == output_stride) {
                plan = &candidate;
                break;
            }
        }
        if (plan == nullptr) {
            lower_plans.emplace_back();
            plan = &lower_plans.back();
            plan->batch = batch;
            plan->rows = rows;
            plan->cols = cols;
            plan->k = k;
            plan->panel_ld = panel_ld;
            plan->ldc = ldc;
            plan->ldd = ldd;
            plan->panel_stride = panel_stride;
            plan->trailing_stride = trailing_stride;
            plan->output_stride = output_stride;
            check_lt(cublasLtMatmulDescCreate(
                         &plan->operation, CUBLAS_COMPUTE_32F, CUDA_R_32F),
                     "cublasLt lower desc create");
            check_lt(cublasLtMatmulDescSetAttribute(
                         plan->operation, CUBLASLT_MATMUL_DESC_TRANSA,
                         &transa, sizeof(transa)),
                     "cublasLt lower TRANSA");
            check_lt(cublasLtMatmulDescSetAttribute(
                         plan->operation, CUBLASLT_MATMUL_DESC_TRANSB,
                         &transb, sizeof(transb)),
                     "cublasLt lower TRANSB");
            check_lt(cublasLtMatrixLayoutCreate(
                         &plan->a_layout, CUDA_R_8F_E4M3,
                         k, rows, panel_ld),
                     "cublasLt lower A layout");
            check_lt(cublasLtMatrixLayoutCreate(
                         &plan->b_layout, CUDA_R_8F_E4M3,
                         k, cols, panel_ld),
                     "cublasLt lower B layout");
            check_lt(cublasLtMatrixLayoutCreate(
                         &plan->c_layout, CUDA_R_32F, rows, cols, ldc),
                     "cublasLt lower C layout");
            check_lt(cublasLtMatrixLayoutCreate(
                         &plan->d_layout, CUDA_R_32F, rows, cols, ldd),
                     "cublasLt lower D layout");
            if (batch > 1) {
                for (cublasLtMatrixLayout_t layout : {
                         plan->a_layout, plan->b_layout,
                         plan->c_layout, plan->d_layout}) {
                    check_lt(cublasLtMatrixLayoutSetAttribute(
                                 layout,
                                 CUBLASLT_MATRIX_LAYOUT_BATCH_COUNT,
                                 &batch, sizeof(batch)),
                             "cublasLt lower batch count");
                }
                for (cublasLtMatrixLayout_t layout : {
                         plan->a_layout, plan->b_layout}) {
                    check_lt(cublasLtMatrixLayoutSetAttribute(
                                 layout,
                                 CUBLASLT_MATRIX_LAYOUT_STRIDED_BATCH_OFFSET,
                                 &panel_stride, sizeof(panel_stride)),
                             "cublasLt lower panel stride");
                }
                check_lt(cublasLtMatrixLayoutSetAttribute(
                             plan->c_layout,
                             CUBLASLT_MATRIX_LAYOUT_STRIDED_BATCH_OFFSET,
                             &trailing_stride, sizeof(trailing_stride)),
                         "cublasLt lower target stride");
                check_lt(cublasLtMatrixLayoutSetAttribute(
                             plan->d_layout,
                             CUBLASLT_MATRIX_LAYOUT_STRIDED_BATCH_OFFSET,
                             &output_stride, sizeof(output_stride)),
                         "cublasLt lower output stride");
            }
        }
        check_lt(cublasLtMatmulDescSetAttribute(
                     plan->operation,
                     CUBLASLT_MATMUL_DESC_A_SCALE_POINTER,
                     &scale_ptr, sizeof(scale_ptr)),
                 "cublasLt lower A scale");
        check_lt(cublasLtMatmulDescSetAttribute(
                     plan->operation,
                     CUBLASLT_MATMUL_DESC_B_SCALE_POINTER,
                     &scale_ptr, sizeof(scale_ptr)),
                 "cublasLt lower B scale");
        if (!plan->ready) {
            cublasLtMatmulPreference_t preference = nullptr;
            check_lt(cublasLtMatmulPreferenceCreate(&preference),
                     "cublasLt lower preference create");
            check_lt(cublasLtMatmulPreferenceSetAttribute(
                         preference,
                         CUBLASLT_MATMUL_PREF_MAX_WORKSPACE_BYTES,
                         &workspace_bytes, sizeof(workspace_bytes)),
                     "cublasLt lower workspace preference");
            int returned = 0;
            cublasLtMatmulHeuristicResult_t heuristic = {};
            check_lt(cublasLtMatmulAlgoGetHeuristic(
                         lt, plan->operation, plan->a_layout,
                         plan->b_layout, plan->c_layout, plan->d_layout,
                         preference, 1, &heuristic, &returned),
                     "cublasLt lower heuristic");
            TORCH_CHECK(returned > 0,
                        "cublasLt found no lower FP8 algorithm");
            plan->algorithm = heuristic.algo;
            plan->ready = true;
            cublasLtMatmulPreferenceDestroy(preference);
        }
        const void* a = panel_ptr +
            static_cast<size_t>(row_start) * panel_ld;
        const void* b = panel_ptr +
            static_cast<size_t>(start) * panel_ld;
        float* c = trailing_ptr + static_cast<size_t>(start) * ldc + row_start;
        float* d = output_ptr + static_cast<size_t>(start) * ldd + row_start;
        unsigned char* workspace_ptr =
            static_cast<unsigned char*>(workspace.data_ptr()) +
            static_cast<size_t>(lane) * workspace_bytes;
        check_lt(cublasLtMatmul(
                     lt, plan->operation,
                     &alpha, a, plan->a_layout,
                     b, plan->b_layout,
                     &beta, c, plan->c_layout,
                     d, plan->d_layout,
                     &plan->algorithm, workspace_ptr,
                     workspace_bytes, queue),
                 "cublasLt lower matmul");
        }
    }
    if (lanes == kLowerLanes) {
        for (int lane = 0; lane < kLowerLanes; ++lane) {
            TORCH_CHECK(cudaEventRecord(
                            lower_done[lane], lower_queues[lane]) ==
                            cudaSuccess,
                        "lower done event record failed");
            TORCH_CHECK(PC_CAT_(cudaStr, eamWaitEvent)(
                            caller, lower_done[lane], 0) == cudaSuccess,
                        "caller lower wait failed");
        }
    }
}

void fp16_lower_rankk_update_lt(
    torch::Tensor trailing,
    torch::Tensor output,
    torch::Tensor panel,
    torch::Tensor workspace,
    int64_t strip_size) {
    TORCH_CHECK(trailing.is_cuda() && trailing.scalar_type() == torch::kFloat32,
                "trailing must be CUDA FP32");
    TORCH_CHECK(trailing.dim() == 3 && trailing.size(1) == trailing.size(2) &&
                trailing.stride(2) == 1,
                "trailing must be batched row-major square views");
    TORCH_CHECK(output.is_cuda() && output.scalar_type() == torch::kFloat32 &&
                output.sizes() == trailing.sizes() && output.stride(2) == 1,
                "output must match trailing");
    TORCH_CHECK(panel.is_cuda() && panel.scalar_type() == torch::kFloat16 &&
                panel.dim() == 3 && panel.stride(2) == 1 &&
                panel.stride(1) == panel.size(2) &&
                panel.size(0) == trailing.size(0) &&
                panel.size(1) == trailing.size(1),
                "panel must be row-contiguous batched FP16 and row aligned");
    TORCH_CHECK(workspace.is_cuda() && workspace.element_size() == 1 &&
                workspace.is_contiguous(),
                "workspace must be contiguous CUDA bytes");
    TORCH_CHECK(strip_size > 0 && strip_size <= trailing.size(1),
                "invalid FP16 lower-update strip size");
    c10::cuda::CUDAGuard guard(trailing.device());
    if (lt == nullptr) check_lt(cublasLtCreate(&lt), "cublasLtCreate");

    const int batch = static_cast<int>(panel.size(0));
    const int m = static_cast<int>(panel.size(1));
    const int panel_ld = static_cast<int>(panel.size(2));
    const int ldc = static_cast<int>(trailing.stride(1));
    const int ldd = static_cast<int>(output.stride(1));
    const int strip = static_cast<int>(strip_size);
    const int64_t panel_stride = panel.stride(0);
    const int64_t trailing_stride = trailing.stride(0);
    const int64_t output_stride = output.stride(0);
    const bool tiled_tail = (batch == 1 || batch == 2) && m == 4096 &&
                            panel_ld == 4096 &&
                            strip == 1024;
    const int lanes = tiled_tail ? kLowerLanes : 1;
    TORCH_CHECK(workspace.numel() % lanes == 0,
                "FP16 lower-update workspace must divide across queues");
    const size_t workspace_bytes =
        static_cast<size_t>(workspace.numel() / lanes);
    const float alpha = -1.0f;
    const float beta = 1.0f;
    const cublasOperation_t transa = CUBLAS_OP_T;
    const cublasOperation_t transb = CUBLAS_OP_N;
    const at::Half* panel_ptr = panel.data_ptr<at::Half>();
    float* trailing_ptr = trailing.data_ptr<float>();
    float* output_ptr = output.data_ptr<float>();
    auto caller = current_q();

    if (tiled_tail) {
        if (!lower_queues_initialized) {
            TORCH_CHECK(cudaEventCreateWithFlags(
                            &lower_ready, cudaEventDisableTiming) ==
                            cudaSuccess,
                        "lower ready event creation failed");
            for (int lane = 0; lane < kLowerLanes; ++lane) {
                TORCH_CHECK(PC_CAT_(cudaStr, eamCreateWithFlags)(
                                &lower_queues[lane], 1) == cudaSuccess,
                            "lower queue creation failed");
                TORCH_CHECK(cudaEventCreateWithFlags(
                                &lower_done[lane], cudaEventDisableTiming) ==
                                cudaSuccess,
                            "lower done event creation failed");
            }
            lower_queues_initialized = true;
        }
        TORCH_CHECK(cudaEventRecord(lower_ready, caller) == cudaSuccess,
                    "lower ready event record failed");
        for (int lane = 0; lane < kLowerLanes; ++lane) {
            TORCH_CHECK(PC_CAT_(cudaStr, eamWaitEvent)(
                            lower_queues[lane], lower_ready, 0) ==
                            cudaSuccess,
                        "lower queue ready wait failed");
        }
    }

    static constexpr int kTailRowBlock[10] = {3, 2, 2, 1, 1, 1, 0, 0, 0, 0};
    static constexpr int kTailColBlock[10] = {3, 3, 2, 3, 2, 1, 3, 2, 1, 0};
    const int job_count = tiled_tail ? 10 : (m + strip - 1) / strip;
    int64_t lane_work[kLowerLanes] = {};
    for (int job = 0; job < job_count; ++job) {
        const int row_start = tiled_tail ? kTailRowBlock[job] * 1024 : 0;
        const int row_end = tiled_tail
            ? row_start + 1024
            : std::min((job + 1) * strip, m);
        const int start = tiled_tail ? kTailColBlock[job] * 1024 : job * strip;
        const int end = tiled_tail ? start + 1024 : row_end;
        const int cols = end - start;
        const int rows = row_end - row_start;
        const int active_k = tiled_tail ? row_end : panel_ld;
        const int64_t job_work =
            static_cast<int64_t>(rows) * cols * active_k;
        int lane = 0;
        for (int candidate = 1; candidate < lanes; ++candidate) {
            if (lane_work[candidate] < lane_work[lane]) lane = candidate;
        }
        lane_work[lane] += job_work;
        auto queue = tiled_tail ? lower_queues[lane] : caller;
        Fp16LowerPlan* plan = nullptr;
        for (auto& candidate : half_lower_plans) {
            if (candidate.batch == batch && candidate.rows == rows &&
                candidate.cols == cols && candidate.k == active_k &&
                candidate.panel_ld == panel_ld &&
                candidate.ldc == ldc &&
                candidate.ldd == ldd &&
                candidate.panel_stride == panel_stride &&
                candidate.trailing_stride == trailing_stride &&
                candidate.output_stride == output_stride &&
                candidate.workspace_bytes == workspace_bytes) {
                plan = &candidate;
                break;
            }
        }
        if (plan == nullptr) {
            half_lower_plans.emplace_back();
            plan = &half_lower_plans.back();
            plan->batch = batch;
            plan->rows = rows;
            plan->cols = cols;
            plan->k = active_k;
            plan->panel_ld = panel_ld;
            plan->ldc = ldc;
            plan->ldd = ldd;
            plan->panel_stride = panel_stride;
            plan->trailing_stride = trailing_stride;
            plan->output_stride = output_stride;
            plan->workspace_bytes = workspace_bytes;
            check_lt(cublasLtMatmulDescCreate(
                         &plan->operation, CUBLAS_COMPUTE_32F, CUDA_R_32F),
                     "cublasLt half lower desc create");
            check_lt(cublasLtMatmulDescSetAttribute(
                         plan->operation, CUBLASLT_MATMUL_DESC_TRANSA,
                         &transa, sizeof(transa)),
                     "cublasLt half lower TRANSA");
            check_lt(cublasLtMatmulDescSetAttribute(
                         plan->operation, CUBLASLT_MATMUL_DESC_TRANSB,
                         &transb, sizeof(transb)),
                     "cublasLt half lower TRANSB");
            check_lt(cublasLtMatrixLayoutCreate(
                         &plan->a_layout, CUDA_R_16F,
                         active_k, rows, panel_ld),
                     "cublasLt half lower A layout");
            check_lt(cublasLtMatrixLayoutCreate(
                         &plan->b_layout, CUDA_R_16F,
                         active_k, cols, panel_ld),
                     "cublasLt half lower B layout");
            check_lt(cublasLtMatrixLayoutCreate(
                         &plan->c_layout, CUDA_R_32F, rows, cols, ldc),
                     "cublasLt half lower C layout");
            check_lt(cublasLtMatrixLayoutCreate(
                         &plan->d_layout, CUDA_R_32F, rows, cols, ldd),
                     "cublasLt half lower D layout");
            for (cublasLtMatrixLayout_t layout : {
                     plan->a_layout, plan->b_layout,
                     plan->c_layout, plan->d_layout}) {
                check_lt(cublasLtMatrixLayoutSetAttribute(
                             layout, CUBLASLT_MATRIX_LAYOUT_BATCH_COUNT,
                             &batch, sizeof(batch)),
                         "cublasLt half lower batch count");
            }
            for (cublasLtMatrixLayout_t layout : {
                     plan->a_layout, plan->b_layout}) {
                check_lt(cublasLtMatrixLayoutSetAttribute(
                             layout,
                             CUBLASLT_MATRIX_LAYOUT_STRIDED_BATCH_OFFSET,
                             &panel_stride, sizeof(panel_stride)),
                         "cublasLt half lower panel stride");
            }
            check_lt(cublasLtMatrixLayoutSetAttribute(
                         plan->c_layout,
                         CUBLASLT_MATRIX_LAYOUT_STRIDED_BATCH_OFFSET,
                         &trailing_stride, sizeof(trailing_stride)),
                     "cublasLt half lower trailing stride");
            check_lt(cublasLtMatrixLayoutSetAttribute(
                         plan->d_layout,
                         CUBLASLT_MATRIX_LAYOUT_STRIDED_BATCH_OFFSET,
                         &output_stride, sizeof(output_stride)),
                     "cublasLt half lower output stride");
        }
        if (!plan->ready) {
            cublasLtMatmulPreference_t preference = nullptr;
            check_lt(cublasLtMatmulPreferenceCreate(&preference),
                     "cublasLt half lower preference create");
            check_lt(cublasLtMatmulPreferenceSetAttribute(
                         preference,
                         CUBLASLT_MATMUL_PREF_MAX_WORKSPACE_BYTES,
                         &workspace_bytes, sizeof(workspace_bytes)),
                     "cublasLt half lower workspace preference");
            int returned = 0;
            cublasLtMatmulHeuristicResult_t heuristic = {};
            check_lt(cublasLtMatmulAlgoGetHeuristic(
                         lt, plan->operation, plan->a_layout,
                         plan->b_layout, plan->c_layout, plan->d_layout,
                         preference, 1, &heuristic, &returned),
                     "cublasLt half lower heuristic");
            TORCH_CHECK(returned > 0,
                        "cublasLt found no batched FP16 lower algorithm");
            plan->algorithm = heuristic.algo;
            plan->ready = true;
            cublasLtMatmulPreferenceDestroy(preference);
        }
        const void* a = panel_ptr +
            static_cast<size_t>(row_start) * panel_ld;
        const void* b = panel_ptr +
            static_cast<size_t>(start) * panel_ld;
        float* c = trailing_ptr +
            static_cast<size_t>(start) * ldc + row_start;
        float* d = output_ptr +
            static_cast<size_t>(start) * ldd + row_start;
        unsigned char* workspace_ptr =
            static_cast<unsigned char*>(workspace.data_ptr()) +
            static_cast<size_t>(lane) * workspace_bytes;
        check_lt(cublasLtMatmul(
                     lt, plan->operation,
                     &alpha, a, plan->a_layout,
                     b, plan->b_layout,
                     &beta, c, plan->c_layout,
                     d, plan->d_layout,
                     &plan->algorithm, workspace_ptr,
                     workspace_bytes, queue),
                 "cublasLt half lower matmul");
    }
    if (tiled_tail) {
        for (int lane = 0; lane < kLowerLanes; ++lane) {
            TORCH_CHECK(cudaEventRecord(
                            lower_done[lane], lower_queues[lane]) ==
                            cudaSuccess,
                        "lower done event record failed");
            TORCH_CHECK(PC_CAT_(cudaStr, eamWaitEvent)(
                            caller, lower_done[lane], 0) == cudaSuccess,
                        "caller lower wait failed");
        }
    }
}

void tf32_lower_rankk_update_4096_lt(
    torch::Tensor target,
    torch::Tensor output,
    torch::Tensor panel,
    torch::Tensor workspace) {
    const bool unbatched =
        target.dim() == 2 && target.size(0) == 4096 &&
        target.size(1) == 4096;
    const bool batched =
        target.dim() == 3 && target.size(0) == 2 &&
        target.size(1) == 4096 && target.size(2) == 4096;
    TORCH_CHECK(target.is_cuda() && target.scalar_type() == torch::kFloat32 &&
                (unbatched || batched) && target.is_contiguous(),
                "target must be contiguous 4096-square CUDA FP32");
    TORCH_CHECK(output.is_cuda() && output.scalar_type() == torch::kFloat32 &&
                output.sizes() == target.sizes() && output.is_contiguous(),
                "output must match target");
    TORCH_CHECK(panel.is_cuda() && panel.scalar_type() == torch::kFloat32 &&
                panel.sizes() == target.sizes() && panel.is_contiguous(),
                "panel must match target");
    TORCH_CHECK(workspace.is_cuda() && workspace.element_size() == 1 &&
                workspace.is_contiguous() &&
                workspace.numel() % kLowerLanes == 0,
                "workspace must be divisible across four queues");
    c10::cuda::CUDAGuard guard(target.device());
    if (lt == nullptr) check_lt(cublasLtCreate(&lt), "cublasLtCreate");

    constexpr int kSize = 4096;
    constexpr int kTile = 1024;
    static constexpr int kSmallBlock[10] = {
        3, 2, 2, 1, 1, 1, 0, 0, 0, 0};
    static constexpr int kLargeBlock[10] = {
        3, 3, 2, 3, 2, 1, 3, 2, 1, 0};
    static constexpr int kJobLane[10] = {
        0, 1, 2, 3, 3, 1, 2, 0, 2, 3};
    const int batch = unbatched ? 1 : 2;
    const int64_t panel_stride = unbatched ? 0 : panel.stride(0);
    const int64_t target_stride = unbatched ? 0 : target.stride(0);
    const int64_t output_stride = unbatched ? 0 : output.stride(0);
    const size_t workspace_bytes =
        static_cast<size_t>(workspace.numel() / kLowerLanes);
    const float alpha = -1.0f;
    const float beta = 1.0f;
    const cublasOperation_t transa = CUBLAS_OP_T;
    const cublasOperation_t transb = CUBLAS_OP_N;
    const float* panel_ptr = panel.data_ptr<float>();
    const float* target_ptr = target.data_ptr<float>();
    float* output_ptr = output.data_ptr<float>();
    auto caller = current_q();

    if (!lower_queues_initialized) {
        TORCH_CHECK(cudaEventCreateWithFlags(
                        &lower_ready, cudaEventDisableTiming) == cudaSuccess,
                    "lower ready event creation failed");
        for (int lane = 0; lane < kLowerLanes; ++lane) {
            TORCH_CHECK(PC_CAT_(cudaStr, eamCreateWithFlags)(
                            &lower_queues[lane], 1) == cudaSuccess,
                        "lower queue creation failed");
            TORCH_CHECK(cudaEventCreateWithFlags(
                            &lower_done[lane], cudaEventDisableTiming) ==
                            cudaSuccess,
                        "lower done event creation failed");
        }
        lower_queues_initialized = true;
    }
    TORCH_CHECK(cudaEventRecord(lower_ready, caller) == cudaSuccess,
                "lower ready event record failed");
    for (int lane = 0; lane < kLowerLanes; ++lane) {
        TORCH_CHECK(PC_CAT_(cudaStr, eamWaitEvent)(
                        lower_queues[lane], lower_ready, 0) == cudaSuccess,
                    "lower queue ready wait failed");
    }

    for (int job = 0; job < 10; ++job) {
        const int small_start = kSmallBlock[job] * kTile;
        const int large_start = kLargeBlock[job] * kTile;
        const int active_k = small_start + kTile;
        const int lane = kJobLane[job];
        Tf32LowerPlan* plan = nullptr;
        for (auto& candidate : tf32_lower_plans) {
            if (candidate.batch == batch && candidate.k == active_k &&
                candidate.panel_stride == panel_stride &&
                candidate.target_stride == target_stride &&
                candidate.output_stride == output_stride &&
                candidate.workspace_bytes == workspace_bytes) {
                plan = &candidate;
                break;
            }
        }
        if (plan == nullptr) {
            tf32_lower_plans.emplace_back();
            plan = &tf32_lower_plans.back();
            plan->batch = batch;
            plan->k = active_k;
            plan->panel_stride = panel_stride;
            plan->target_stride = target_stride;
            plan->output_stride = output_stride;
            plan->workspace_bytes = workspace_bytes;
            check_lt(cublasLtMatmulDescCreate(
                         &plan->operation,
                         CUBLAS_COMPUTE_32F_FAST_TF32, CUDA_R_32F),
                     "cublasLt TF32 lower desc create");
            check_lt(cublasLtMatmulDescSetAttribute(
                         plan->operation, CUBLASLT_MATMUL_DESC_TRANSA,
                         &transa, sizeof(transa)),
                     "cublasLt TF32 lower TRANSA");
            check_lt(cublasLtMatmulDescSetAttribute(
                         plan->operation, CUBLASLT_MATMUL_DESC_TRANSB,
                         &transb, sizeof(transb)),
                     "cublasLt TF32 lower TRANSB");
            check_lt(cublasLtMatrixLayoutCreate(
                         &plan->a_layout, CUDA_R_32F,
                         active_k, kTile, kSize),
                     "cublasLt TF32 lower A layout");
            check_lt(cublasLtMatrixLayoutCreate(
                         &plan->b_layout, CUDA_R_32F,
                         active_k, kTile, kSize),
                     "cublasLt TF32 lower B layout");
            check_lt(cublasLtMatrixLayoutCreate(
                         &plan->c_layout, CUDA_R_32F,
                         kTile, kTile, kSize),
                     "cublasLt TF32 lower C layout");
            check_lt(cublasLtMatrixLayoutCreate(
                         &plan->d_layout, CUDA_R_32F,
                         kTile, kTile, kSize),
                     "cublasLt TF32 lower D layout");
            if (batch > 1) {
                for (cublasLtMatrixLayout_t layout : {
                         plan->a_layout, plan->b_layout,
                         plan->c_layout, plan->d_layout}) {
                    check_lt(cublasLtMatrixLayoutSetAttribute(
                                 layout,
                                 CUBLASLT_MATRIX_LAYOUT_BATCH_COUNT,
                                 &batch, sizeof(batch)),
                             "cublasLt TF32 lower batch count");
                }
                for (cublasLtMatrixLayout_t layout : {
                         plan->a_layout, plan->b_layout}) {
                    check_lt(cublasLtMatrixLayoutSetAttribute(
                                 layout,
                                 CUBLASLT_MATRIX_LAYOUT_STRIDED_BATCH_OFFSET,
                                 &panel_stride, sizeof(panel_stride)),
                             "cublasLt TF32 lower panel stride");
                }
                check_lt(cublasLtMatrixLayoutSetAttribute(
                             plan->c_layout,
                             CUBLASLT_MATRIX_LAYOUT_STRIDED_BATCH_OFFSET,
                             &target_stride, sizeof(target_stride)),
                         "cublasLt TF32 lower target stride");
                check_lt(cublasLtMatrixLayoutSetAttribute(
                             plan->d_layout,
                             CUBLASLT_MATRIX_LAYOUT_STRIDED_BATCH_OFFSET,
                             &output_stride, sizeof(output_stride)),
                         "cublasLt TF32 lower output stride");
            }
        }
        if (!plan->ready) {
            cublasLtMatmulPreference_t preference = nullptr;
            check_lt(cublasLtMatmulPreferenceCreate(&preference),
                     "cublasLt TF32 lower preference create");
            check_lt(cublasLtMatmulPreferenceSetAttribute(
                         preference,
                         CUBLASLT_MATMUL_PREF_MAX_WORKSPACE_BYTES,
                         &workspace_bytes, sizeof(workspace_bytes)),
                     "cublasLt TF32 lower workspace preference");
            int returned = 0;
            cublasLtMatmulHeuristicResult_t heuristic = {};
            check_lt(cublasLtMatmulAlgoGetHeuristic(
                         lt, plan->operation, plan->a_layout,
                         plan->b_layout, plan->c_layout, plan->d_layout,
                         preference, 1, &heuristic, &returned),
                     "cublasLt TF32 lower heuristic");
            TORCH_CHECK(returned > 0,
                        "cublasLt found no TF32 lower algorithm");
            plan->algorithm = heuristic.algo;
            plan->ready = true;
            cublasLtMatmulPreferenceDestroy(preference);
        }
        const float* a = panel_ptr +
            static_cast<size_t>(small_start) * kSize;
        const float* b = panel_ptr +
            static_cast<size_t>(large_start) * kSize;
        const float* c = target_ptr +
            static_cast<size_t>(large_start) * kSize + small_start;
        float* d = output_ptr +
            static_cast<size_t>(large_start) * kSize + small_start;
        unsigned char* workspace_ptr =
            static_cast<unsigned char*>(workspace.data_ptr()) +
            static_cast<size_t>(lane) * workspace_bytes;
        check_lt(cublasLtMatmul(
                     lt, plan->operation,
                     &alpha, a, plan->a_layout,
                     b, plan->b_layout,
                     &beta, c, plan->c_layout,
                     d, plan->d_layout,
                     &plan->algorithm, workspace_ptr,
                     workspace_bytes, lower_queues[lane]),
                 "cublasLt TF32 lower matmul");
    }
    for (int lane = 0; lane < kLowerLanes; ++lane) {
        TORCH_CHECK(cudaEventRecord(
                        lower_done[lane], lower_queues[lane]) == cudaSuccess,
                    "lower done event record failed");
        TORCH_CHECK(PC_CAT_(cudaStr, eamWaitEvent)(
                        caller, lower_done[lane], 0) == cudaSuccess,
                    "caller lower wait failed");
    }
}

__global__ void clear_upper_kernel(
    float* __restrict__ matrix,
    int n,
    size_t matrix_stride) {
    const int warp = threadIdx.x >> 5;
    const int lane = threadIdx.x & 31;
    const int row = blockIdx.x * 8 + warp;
    if (row >= n) return;
    float* matrix_row = matrix +
        static_cast<size_t>(blockIdx.y) * matrix_stride +
        static_cast<size_t>(row) * n;
    for (int col = row + 1 + lane; col < n; col += 32) {
        matrix_row[col] = 0.0f;
    }
}

__global__ void clear_upper_view_kernel(
    float* __restrict__ matrix,
    int n,
    int64_t batch_stride,
    int64_t row_stride) {
    const int warp = threadIdx.x >> 5;
    const int lane = threadIdx.x & 31;
    const int row = blockIdx.x * 8 + warp;
    if (row >= n) return;
    float* matrix_row = matrix +
        static_cast<int64_t>(blockIdx.y) * batch_stride +
        static_cast<int64_t>(row) * row_stride;
    for (int col = row + 1 + lane; col < n; col += 32) {
        matrix_row[col] = 0.0f;
    }
}

__global__ void clear_lower_kernel(
    float* __restrict__ matrix,
    int n,
    size_t matrix_stride) {
    const int warp = threadIdx.x >> 5;
    const int lane = threadIdx.x & 31;
    const int row = blockIdx.x * 8 + warp;
    if (row >= n) return;
    float* matrix_row = matrix +
        static_cast<size_t>(blockIdx.y) * matrix_stride +
        static_cast<size_t>(row) * n;
    for (int col = lane; col < row; col += 32) {
        matrix_row[col] = 0.0f;
    }
}

void clear_upper(torch::Tensor matrix) {
    TORCH_CHECK(matrix.is_cuda() && matrix.scalar_type() == torch::kFloat32 &&
                matrix.is_contiguous() && matrix.dim() == 3 &&
                matrix.size(1) == matrix.size(2),
                "matrix must be contiguous square CUDA FP32");
    c10::cuda::CUDAGuard guard(matrix.device());
    const int batch = static_cast<int>(matrix.size(0));
    const int n = static_cast<int>(matrix.size(1));
    const size_t stride = static_cast<size_t>(n) * n;
    const dim3 grid((n + 7) / 8, batch);
    clear_upper_kernel<<<grid, 256, 0, current_q()>>>(
        matrix.data_ptr<float>(), n, stride);
    const cudaError_t error = cudaGetLastError();
    TORCH_CHECK(error == cudaSuccess, "clear_upper failed: ",
                cudaGetErrorString(error));
}

void clear_upper_view(torch::Tensor matrix) {
    TORCH_CHECK(matrix.is_cuda() && matrix.scalar_type() == torch::kFloat32 &&
                matrix.dim() == 3 && matrix.size(1) == matrix.size(2) &&
                matrix.stride(2) == 1,
                "matrix must be a row-contiguous square CUDA FP32 view");
    c10::cuda::CUDAGuard guard(matrix.device());
    const int batch = static_cast<int>(matrix.size(0));
    const int n = static_cast<int>(matrix.size(1));
    const dim3 grid((n + 7) / 8, batch);
    clear_upper_view_kernel<<<grid, 256, 0, current_q()>>>(
        matrix.data_ptr<float>(), n, matrix.stride(0), matrix.stride(1));
    const cudaError_t error = cudaGetLastError();
    TORCH_CHECK(error == cudaSuccess, "clear_upper_view failed: ",
                cudaGetErrorString(error));
}

__global__ void diagonal_tail_kernel(
    float* __restrict__ matrix,
    int n,
    int64_t batch_stride,
    int64_t row_stride) {
    const int warp = threadIdx.x >> 5;
    const int lane = threadIdx.x & 31;
    const int row = blockIdx.x * 8 + warp;
    if (row >= n) return;
    float* matrix_row = matrix +
        static_cast<int64_t>(blockIdx.y) * batch_stride +
        static_cast<int64_t>(row) * row_stride;
    for (int col = lane; col < n; col += 32) {
        matrix_row[col] = col == row
            ? sqrtf(fmaxf(matrix_row[col], 1.0e-30f))
            : 0.0f;
    }
}

void diagonal_tail(torch::Tensor matrix) {
    TORCH_CHECK(matrix.is_cuda() && matrix.scalar_type() == torch::kFloat32 &&
                matrix.dim() == 3 && matrix.size(1) == matrix.size(2) &&
                matrix.stride(2) == 1,
                "matrix must be a row-contiguous square CUDA FP32 view");
    c10::cuda::CUDAGuard guard(matrix.device());
    const int batch = static_cast<int>(matrix.size(0));
    const int n = static_cast<int>(matrix.size(1));
    const dim3 grid((n + 7) / 8, batch);
    diagonal_tail_kernel<<<grid, 256, 0, current_q()>>>(
        matrix.data_ptr<float>(), n, matrix.stride(0), matrix.stride(1));
    const cudaError_t error = cudaGetLastError();
    TORCH_CHECK(error == cudaSuccess, "diagonal_tail failed: ",
                cudaGetErrorString(error));
}

__global__ void jacobi_tail_diagonal_kernel(
    const float* __restrict__ matrix,
    float* __restrict__ inverse_diagonal,
    int n,
    int64_t batch_stride,
    int64_t row_stride) {
    const int index = blockIdx.x * blockDim.x + threadIdx.x;
    if (index >= n) return;
    const float diagonal = matrix[
        static_cast<int64_t>(blockIdx.y) * batch_stride +
        static_cast<int64_t>(index) * row_stride + index];
    inverse_diagonal[static_cast<int64_t>(blockIdx.y) * n + index] =
        rsqrtf(fmaxf(diagonal, 1.0e-30f));
}

__global__ void jacobi_refine_reciprocal_diagonal_kernel(
    const float* __restrict__ matrix,
    float* __restrict__ inverse_diagonal,
    int n,
    int64_t batch_stride,
    int64_t row_stride) {
    const int index = blockIdx.x * blockDim.x + threadIdx.x;
    if (index >= n) return;
    const float diagonal = matrix[
        static_cast<int64_t>(blockIdx.y) * batch_stride +
        static_cast<int64_t>(index) * row_stride + index];
    inverse_diagonal[static_cast<int64_t>(blockIdx.y) * n + index] =
        1.0f / fmaxf(diagonal, 1.0e-30f);
}

__global__ void jacobi_tail_factor_kernel(
    float* __restrict__ matrix,
    const float* __restrict__ inverse_diagonal,
    int n,
    float alpha,
    int64_t batch_stride,
    int64_t row_stride) {
    const int warp = threadIdx.x >> 5;
    const int lane = threadIdx.x & 31;
    const int row = blockIdx.x * 8 + warp;
    if (row >= n) return;
    float* matrix_row = matrix +
        static_cast<int64_t>(blockIdx.y) * batch_stride +
        static_cast<int64_t>(row) * row_stride;
    const float* inverse = inverse_diagonal +
        static_cast<int64_t>(blockIdx.y) * n;
    const float diagonal = matrix_row[row];
    float energy = 0.0f;
    for (int col = lane; col < row; col += 32) {
        const float value = alpha * matrix_row[col] * inverse[col];
        matrix_row[col] = value;
        energy = fmaf(value, value, energy);
    }
    #pragma unroll
    for (int offset = 16; offset; offset >>= 1) {
        energy += __shfl_down_sync(0xffffffffu, energy, offset);
    }
    if (lane == 0) {
        matrix_row[row] = sqrtf(fmaxf(diagonal - energy, 1.0e-30f));
    }
    for (int col = row + 1 + lane; col < n; col += 32) {
        matrix_row[col] = 0.0f;
    }
}

void jacobi_tail(torch::Tensor matrix, double alpha) {
    TORCH_CHECK(matrix.is_cuda() && matrix.scalar_type() == torch::kFloat32 &&
                matrix.dim() == 3 && matrix.size(1) == matrix.size(2) &&
                matrix.stride(2) == 1,
                "matrix must be a row-contiguous square CUDA FP32 view");
    TORCH_CHECK(alpha > 0.0 && alpha <= 1.0,
                "alpha must be in (0, 1]");
    c10::cuda::CUDAGuard guard(matrix.device());
    const int batch = static_cast<int>(matrix.size(0));
    const int n = static_cast<int>(matrix.size(1));
    auto inverse_diagonal = torch::empty({batch, n}, matrix.options());
    jacobi_tail_diagonal_kernel<<<dim3((n + 255) / 256, batch), 256, 0,
                                        current_q()>>>(
        matrix.data_ptr<float>(), inverse_diagonal.data_ptr<float>(), n,
        matrix.stride(0), matrix.stride(1));
    jacobi_tail_factor_kernel<<<dim3((n + 7) / 8, batch), 256, 0,
                                  current_q()>>>(
        matrix.data_ptr<float>(), inverse_diagonal.data_ptr<float>(), n,
        static_cast<float>(alpha), matrix.stride(0), matrix.stride(1));
    const cudaError_t error = cudaGetLastError();
    TORCH_CHECK(error == cudaSuccess, "jacobi_tail failed: ",
                cudaGetErrorString(error));
}

__global__ void jacobi_tail_refine_kernel(
    float* __restrict__ matrix,
    const float* __restrict__ residual,
    const float* __restrict__ target_diagonal,
    const float* __restrict__ inverse_diagonal,
    int n,
    float beta,
    int64_t matrix_batch_stride,
    int64_t matrix_row_stride,
    int64_t residual_batch_stride,
    int64_t residual_row_stride,
    int64_t target_batch_stride,
    int64_t target_diagonal_stride,
    int first_row) {
    const int warp = threadIdx.x >> 5;
    const int lane = threadIdx.x & 31;
    const int row = first_row + blockIdx.x * 8 + warp;
    if (row >= n) return;
    float* matrix_row = matrix +
        static_cast<int64_t>(blockIdx.y) * matrix_batch_stride +
        static_cast<int64_t>(row) * matrix_row_stride;
    const float* residual_row = residual +
        static_cast<int64_t>(blockIdx.y) * residual_batch_stride +
        static_cast<int64_t>(row) * residual_row_stride;
    const float target_value = target_diagonal[
        static_cast<int64_t>(blockIdx.y) * target_batch_stride +
        static_cast<int64_t>(row) * target_diagonal_stride];
    const float* inverse = inverse_diagonal +
        static_cast<int64_t>(blockIdx.y) * n;
    float energy = 0.0f;
    for (int col = lane; col < row; col += 32) {
        const float correction = residual_row[col] * inverse[col];
        const float value = fmaf(beta, correction, matrix_row[col]);
        matrix_row[col] = value;
        energy = fmaf(value, value, energy);
    }
    #pragma unroll
    for (int offset = 16; offset; offset >>= 1) {
        energy += __shfl_down_sync(0xffffffffu, energy, offset);
    }
    if (lane == 0) {
        matrix_row[row] = sqrtf(
            fmaxf(target_value - energy, 1.0e-30f));
    }
}

void jacobi_refine(
    torch::Tensor matrix,
    torch::Tensor residual,
    torch::Tensor target,
    double beta,
    int64_t first_row,
    bool reciprocal_diagonal) {
    TORCH_CHECK(matrix.is_cuda() && matrix.scalar_type() == torch::kFloat32 &&
                matrix.dim() == 3 && matrix.size(1) == matrix.size(2) &&
                matrix.stride(2) == 1,
                "matrix must be a row-contiguous square CUDA FP32 view");
    TORCH_CHECK(residual.is_cuda() && residual.scalar_type() == torch::kFloat32 &&
                residual.sizes() == matrix.sizes() && residual.stride(2) == 1,
                "residual must match matrix");
    const bool target_matrix =
        target.is_cuda() && target.scalar_type() == torch::kFloat32 &&
        target.dim() == 3 && target.sizes() == matrix.sizes() &&
        target.stride(2) == 1;
    const bool target_diagonal =
        target.is_cuda() && target.scalar_type() == torch::kFloat32 &&
        target.dim() == 2 && target.size(0) == matrix.size(0) &&
        target.size(1) == matrix.size(1) && target.stride(1) == 1;
    TORCH_CHECK(target_matrix || target_diagonal,
                "target must be the matrix or its diagonal");
    TORCH_CHECK(beta > 0.0 && beta <= 1.0,
                "beta must be in (0, 1]");
    TORCH_CHECK(first_row >= 0 && first_row <= matrix.size(1),
                "first row must be inside the matrix");
    c10::cuda::CUDAGuard guard(matrix.device());
    const int batch = static_cast<int>(matrix.size(0));
    const int n = static_cast<int>(matrix.size(1));
    auto inverse_diagonal = torch::empty({batch, n}, matrix.options());
    if (reciprocal_diagonal) {
        jacobi_refine_reciprocal_diagonal_kernel
            <<<dim3((n + 255) / 256, batch), 256, 0, current_q()>>>(
                matrix.data_ptr<float>(), inverse_diagonal.data_ptr<float>(),
                n, matrix.stride(0), matrix.stride(1));
    } else {
        jacobi_tail_diagonal_kernel
            <<<dim3((n + 255) / 256, batch), 256, 0, current_q()>>>(
                matrix.data_ptr<float>(), inverse_diagonal.data_ptr<float>(),
                n, matrix.stride(0), matrix.stride(1));
    }
    const int64_t target_batch_stride = target.stride(0);
    const int64_t target_diagonal_stride = target_matrix
        ? target.stride(1) + target.stride(2)
        : target.stride(1);
    jacobi_tail_refine_kernel<<<dim3((n - first_row + 7) / 8, batch), 256, 0,
                                  current_q()>>>(
        matrix.data_ptr<float>(), residual.data_ptr<float>(),
        target.data_ptr<float>(), inverse_diagonal.data_ptr<float>(), n,
        static_cast<float>(beta), matrix.stride(0), matrix.stride(1),
        residual.stride(0), residual.stride(1), target_batch_stride,
        target_diagonal_stride, static_cast<int>(first_row));
    const cudaError_t error = cudaGetLastError();
    TORCH_CHECK(error == cudaSuccess, "jacobi_refine failed: ",
                cudaGetErrorString(error));
}

template <int N, int ROWS>
__global__ void init_lower_kernel(
    const float* __restrict__ input,
    float* __restrict__ output) {
    constexpr int VECTORS_PER_ROW = N / 4;
    const int matrix = blockIdx.x;
    const int row_base = blockIdx.y * ROWS;
    const size_t matrix_base = static_cast<size_t>(matrix) * N * N;
    const float4* input4 = reinterpret_cast<const float4*>(input);
    float4* output4 = reinterpret_cast<float4*>(output);
    const size_t matrix_base4 = matrix_base / 4;
    for (int index = threadIdx.x; index < ROWS * VECTORS_PER_ROW;
         index += blockDim.x) {
        const int row_offset = index / VECTORS_PER_ROW;
        const int row = row_base + row_offset;
        const int vector_col = index - row_offset * VECTORS_PER_ROW;
        const int col = 4 * vector_col;
        float4 value = make_float4(0.0f, 0.0f, 0.0f, 0.0f);
        if (col <= row) {
            value = input4[matrix_base4 +
                           static_cast<size_t>(row) * VECTORS_PER_ROW +
                           vector_col];
            if (col + 1 > row) value.y = 0.0f;
            if (col + 2 > row) value.z = 0.0f;
            if (col + 3 > row) value.w = 0.0f;
        }
        output4[matrix_base4 +
                static_cast<size_t>(row) * VECTORS_PER_ROW + vector_col] =
            value;
    }
}

torch::Tensor init_lower(torch::Tensor input) {
    TORCH_CHECK(input.is_cuda() && input.scalar_type() == torch::kFloat32 &&
                input.is_contiguous() && input.dim() == 3 &&
                input.size(1) == input.size(2),
                "input must be contiguous square CUDA FP32");
    c10::cuda::CUDAGuard guard(input.device());
    const int batch = static_cast<int>(input.size(0));
    const int n = static_cast<int>(input.size(1));
    auto output = torch::empty_like(input);
#define LAUNCH_INIT_LOWER(N)                                               \
    init_lower_kernel<N, 8><<<dim3(batch, N / 8), 256, 0, current_q()>>>( \
        input.data_ptr<float>(), output.data_ptr<float>())
    if (n == 1024) {
        LAUNCH_INIT_LOWER(1024);
    } else if (n == 2048) {
        LAUNCH_INIT_LOWER(2048);
    } else if (n == 4096) {
        LAUNCH_INIT_LOWER(4096);
    } else if (n == 8192) {
        LAUNCH_INIT_LOWER(8192);
    } else if (n == 16384) {
        LAUNCH_INIT_LOWER(16384);
    } else if (n == 32768) {
        LAUNCH_INIT_LOWER(32768);
    } else {
        TORCH_CHECK(false, "unsupported init_lower size");
    }
#undef LAUNCH_INIT_LOWER
    const cudaError_t error = cudaGetLastError();
    TORCH_CHECK(error == cudaSuccess, "init_lower failed: ",
                cudaGetErrorString(error));
    return output;
}

void init_lower_into(torch::Tensor input, torch::Tensor output) {
    TORCH_CHECK(input.is_cuda() && input.scalar_type() == torch::kFloat32 &&
                input.is_contiguous() && input.dim() == 3 &&
                input.size(1) == input.size(2),
                "input must be contiguous square CUDA FP32");
    TORCH_CHECK(output.is_cuda() && output.scalar_type() == torch::kFloat32 &&
                output.is_contiguous() && output.sizes() == input.sizes(),
                "output must be a matching contiguous CUDA FP32 tensor");
    c10::cuda::CUDAGuard guard(input.device());
    const int batch = static_cast<int>(input.size(0));
    const int n = static_cast<int>(input.size(1));
#define LAUNCH_INIT_LOWER_INTO(N)                                         \
    init_lower_kernel<N, 8><<<dim3(batch, N / 8), 256, 0, current_q()>>>( \
        input.data_ptr<float>(), output.data_ptr<float>())
    if (n == 8192) {
        LAUNCH_INIT_LOWER_INTO(8192);
    } else if (n == 16384) {
        LAUNCH_INIT_LOWER_INTO(16384);
    } else if (n == 32768) {
        LAUNCH_INIT_LOWER_INTO(32768);
    } else {
        TORCH_CHECK(false, "unsupported init_lower_into size");
    }
#undef LAUNCH_INIT_LOWER_INTO
    const cudaError_t error = cudaGetLastError();
    TORCH_CHECK(error == cudaSuccess, "init_lower_into failed: ",
                cudaGetErrorString(error));
}

template <int N, int ROWS>
__global__ void reuse_lower_kernel(
    const float* __restrict__ input,
    float* __restrict__ output) {
    constexpr int VECTORS_PER_ROW = N / 4;
    const int matrix = blockIdx.x;
    const int row_base = blockIdx.y * ROWS;
    const size_t matrix_base = static_cast<size_t>(matrix) * N * N;
    const float4* input4 = reinterpret_cast<const float4*>(input);
    float4* output4 = reinterpret_cast<float4*>(output);
    const size_t matrix_base4 = matrix_base / 4;
    #pragma unroll
    for (int row_offset = 0; row_offset < ROWS; ++row_offset) {
        const int row = row_base + row_offset;
        const int row_vectors = row / 4 + 1;
        for (int vector_col = threadIdx.x; vector_col < row_vectors;
             vector_col += blockDim.x) {
            const int col = 4 * vector_col;
            float4 value = input4[
                matrix_base4 + static_cast<size_t>(row) * VECTORS_PER_ROW +
                vector_col];
            if (col + 1 > row) value.y = 0.0f;
            if (col + 2 > row) value.z = 0.0f;
            if (col + 3 > row) value.w = 0.0f;
            output4[matrix_base4 +
                    static_cast<size_t>(row) * VECTORS_PER_ROW +
                    vector_col] = value;
        }
    }
}

void reuse_lower_into(torch::Tensor input, torch::Tensor output) {
    TORCH_CHECK(input.is_cuda() && input.scalar_type() == torch::kFloat32 &&
                input.is_contiguous() && input.dim() == 3 &&
                input.size(1) == input.size(2),
                "input must be contiguous square CUDA FP32");
    TORCH_CHECK(output.is_cuda() && output.scalar_type() == torch::kFloat32 &&
                output.is_contiguous() && output.sizes() == input.sizes(),
                "output must be a matching contiguous CUDA FP32 tensor");
    c10::cuda::CUDAGuard guard(input.device());
    const int batch = static_cast<int>(input.size(0));
    const int n = static_cast<int>(input.size(1));
#define LAUNCH_REUSE_LOWER(N)                                             \
    reuse_lower_kernel<N, 8><<<dim3(batch, N / 8), 256, 0, current_q()>>>(\
        input.data_ptr<float>(), output.data_ptr<float>())
    if (n == 8192) {
        LAUNCH_REUSE_LOWER(8192);
    } else if (n == 16384) {
        LAUNCH_REUSE_LOWER(16384);
    } else if (n == 32768) {
        LAUNCH_REUSE_LOWER(32768);
    } else {
        TORCH_CHECK(false, "unsupported reuse_lower_into size");
    }
#undef LAUNCH_REUSE_LOWER
    const cudaError_t error = cudaGetLastError();
    TORCH_CHECK(error == cudaSuccess, "reuse_lower_into failed: ",
                cudaGetErrorString(error));
}

template <int N>
__global__ void prepare_column_major(
    const float* __restrict__ input,
    float* __restrict__ raw,
    float** __restrict__ pointers) {
    constexpr int STRIDE = N * N;
    const int matrix = blockIdx.x;
    const size_t base = static_cast<size_t>(matrix) * STRIDE;
    if (threadIdx.x == 0) pointers[matrix] = raw + base;
    const float4* input4 = reinterpret_cast<const float4*>(input);
    float4* raw4 = reinterpret_cast<float4*>(raw);
    const size_t base4 = base / 4;
    for (int index = threadIdx.x; index < STRIDE / 4;
         index += blockDim.x) {
        raw4[base4 + index] = input4[base4 + index];
    }
}

__global__ void prepare_pointer_array(
    float* __restrict__ raw,
    float** __restrict__ pointers,
    size_t stride,
    int batch) {
    const int matrix = blockIdx.x * blockDim.x + threadIdx.x;
    if (matrix < batch) {
        pointers[matrix] = raw + static_cast<size_t>(matrix) * stride;
    }
}

template <int N, int ROWS>
__global__ void prepare_view(
    const float* __restrict__ input,
    float* __restrict__ raw) {
    constexpr int VECTORS_PER_ROW = N / 4;
    const int matrix = blockIdx.x;
    const int row_base = blockIdx.y * ROWS;
    const size_t matrix_base = static_cast<size_t>(matrix) * N * N;
    const float4* input4 = reinterpret_cast<const float4*>(input);
    float4* raw4 = reinterpret_cast<float4*>(raw);
    const size_t matrix_base4 = matrix_base / 4;
    for (int index = threadIdx.x; index < ROWS * VECTORS_PER_ROW;
         index += blockDim.x) {
        const int row = row_base + index / VECTORS_PER_ROW;
        const int vector_col = index - (index / VECTORS_PER_ROW) * VECTORS_PER_ROW;
        const int col = 4 * vector_col;
        float4 value = make_float4(0.0f, 0.0f, 0.0f, 0.0f);
        if (col + 3 >= row) {
            value = input4[matrix_base4 +
                           static_cast<size_t>(row) * VECTORS_PER_ROW +
                           vector_col];
            if (col < row) value.x = 0.0f;
            if (col + 1 < row) value.y = 0.0f;
            if (col + 2 < row) value.z = 0.0f;
        }
        raw4[matrix_base4 +
             static_cast<size_t>(row) * VECTORS_PER_ROW + vector_col] = value;
    }
}

template <int N>
__global__ void transpose_upper_to_lower(
    const float* __restrict__ raw,
    float* __restrict__ output) {
    __shared__ float tile[32][33];
    constexpr int STRIDE = N * N;
    constexpr int TILES = N / 32;
    const int matrix = blockIdx.x / TILES;
    const int tile_row = blockIdx.x - matrix * TILES;
    const int lane = threadIdx.x & 31;
    const int warp = threadIdx.x >> 5;
    const size_t base = static_cast<size_t>(matrix) * STRIDE;
    const int row_base = tile_row * 32;
    for (int tile_col = 0; tile_col <= tile_row; ++tile_col) {
        const int col_base = tile_col * 32;
        #pragma unroll
        for (int q = 0; q < 4; ++q) {
            const int row = warp + 8 * q;
            tile[row][lane] = raw[
                base + static_cast<size_t>(col_base + row) * N +
                row_base + lane];
        }
        __syncthreads();
        #pragma unroll
        for (int q = 0; q < 4; ++q) {
            const int row = warp + 8 * q;
            const float value = tile[lane][row];
            output[base + static_cast<size_t>(row_base + row) * N +
                   col_base + lane] =
                (tile_row > tile_col || row >= lane) ? value : 0.0f;
            if (tile_row > tile_col) {
                output[base + static_cast<size_t>(col_base + row) * N +
                       row_base + lane] = 0.0f;
            }
        }
        __syncthreads();
    }
}

torch::Tensor direct_potrf(torch::Tensor input) {
    TORCH_CHECK(input.is_cuda() && input.scalar_type() == torch::kFloat32,
                "input must be CUDA FP32");
    TORCH_CHECK(input.is_contiguous() && input.dim() == 3 &&
                input.size(1) == input.size(2),
                "input must be contiguous (batch,n,n)");
    c10::cuda::CUDAGuard guard(input.device());
    const int batch = static_cast<int>(input.size(0));
    const int n = static_cast<int>(input.size(1));
    TORCH_CHECK(n == 64 || n == 128 || n == 256 || n == 512,
                "unsupported direct Cholesky size");
    auto raw = torch::empty_like(input);
    auto pointers = torch::empty({batch}, input.options().dtype(torch::kInt64));
    auto info = torch::empty({batch}, input.options().dtype(torch::kInt32));
    if (n == 64) {
        prepare_column_major<64><<<batch, 256>>>(
            input.data_ptr<float>(), raw.data_ptr<float>(),
            reinterpret_cast<float**>(pointers.data_ptr<int64_t>()));
    } else if (n == 128) {
        prepare_column_major<128><<<batch, 256>>>(
            input.data_ptr<float>(), raw.data_ptr<float>(),
            reinterpret_cast<float**>(pointers.data_ptr<int64_t>()));
    } else {
        const size_t stride = static_cast<size_t>(n) * n;
        if (n == 256) {
            prepare_view<256, 16><<<dim3(batch, 16), 256, 0, current_q()>>>(
                input.data_ptr<float>(), raw.data_ptr<float>());
        } else {
            prepare_view<512, 32><<<dim3(batch, 16), 256, 0, current_q()>>>(
                input.data_ptr<float>(), raw.data_ptr<float>());
        }
        prepare_pointer_array<<<(batch + 255) / 256, 256, 0, current_q()>>>(
            raw.data_ptr<float>(),
            reinterpret_cast<float**>(pointers.data_ptr<int64_t>()),
            stride, batch);
    }
    if (solver == nullptr) {
        const cusolverStatus_t create_status = cusolverDnCreate(&solver);
        TORCH_CHECK(create_status == CUSOLVER_STATUS_SUCCESS,
                    "cusolverDnCreate failed: ", static_cast<int>(create_status));
    }
    const cusolverStatus_t status = cusolverDnSpotrfBatched(
        solver, CUBLAS_FILL_MODE_LOWER, n,
        reinterpret_cast<float**>(pointers.data_ptr<int64_t>()), n,
        info.data_ptr<int>(), batch);
    TORCH_CHECK(status == CUSOLVER_STATUS_SUCCESS,
                "cusolverDnSpotrfBatched failed: ", static_cast<int>(status));
    if (n == 64 || n == 128) {
        const size_t stride = static_cast<size_t>(n) * n;
        const dim3 clear_grid((n + 7) / 8, batch);
        clear_lower_kernel<<<clear_grid, 256>>>(raw.data_ptr<float>(), n, stride);
    }
    const cudaError_t error = cudaGetLastError();
    TORCH_CHECK(error == cudaSuccess, "direct_potrf launch failed: ",
                cudaGetErrorString(error));
    return raw.transpose(1, 2);
}

torch::Tensor direct_potrf_split4(torch::Tensor input) {
    TORCH_CHECK(input.is_cuda() && input.scalar_type() == torch::kFloat32,
                "input must be CUDA FP32");
    TORCH_CHECK(input.is_contiguous() && input.dim() == 3 &&
                input.size(0) == 640 && input.size(1) == 512 &&
                input.size(2) == 512,
                "input must be contiguous batch640 n512");
    c10::cuda::CUDAGuard guard(input.device());
    constexpr int batch = 640;
    constexpr int groups = 5;
    constexpr int group_batch = batch / groups;
    constexpr int n = 512;
    constexpr size_t stride = static_cast<size_t>(n) * n;
    auto raw = torch::empty_like(input);
    auto pointers = torch::empty({batch}, input.options().dtype(torch::kInt64));
    auto info = torch::empty({batch}, input.options().dtype(torch::kInt32));
    prepare_view<n, 32><<<dim3(batch, n / 32), 256, 0, current_q()>>>(
        input.data_ptr<float>(), raw.data_ptr<float>());
    prepare_pointer_array<<<(batch + 255) / 256, 256, 0, current_q()>>>(
        raw.data_ptr<float>(),
        reinterpret_cast<float**>(pointers.data_ptr<int64_t>()),
        stride, batch);

    using Queue = decltype(current_q());
    static Queue queues[groups] = {};
    static cudaEvent_t ready = nullptr;
    static cudaEvent_t done[groups] = {};
    if (ready == nullptr) {
        TORCH_CHECK(cudaEventCreateWithFlags(
                        &ready, cudaEventDisableTiming) == cudaSuccess,
                    "batch4 ready event creation failed");
    }
    for (int index = 0; index < groups; ++index) {
        if (queues[index] == nullptr) {
            const cudaError_t create_error =
                PC_CAT_(cudaStr, eamCreateWithFlags)(&queues[index], 1);
            TORCH_CHECK(create_error == cudaSuccess,
                        "batch4 queue creation failed: ",
                        cudaGetErrorString(create_error));
        }
        if (done[index] == nullptr) {
            TORCH_CHECK(cudaEventCreateWithFlags(
                            &done[index], cudaEventDisableTiming) == cudaSuccess,
                        "batch4 done event creation failed");
        }
        if (solver_batch4[index] == nullptr) {
            const cusolverStatus_t create_status =
                cusolverDnCreate(&solver_batch4[index]);
            TORCH_CHECK(create_status == CUSOLVER_STATUS_SUCCESS,
                        "batch4 solver creation failed: ",
                        static_cast<int>(create_status));
        }
        const cusolverStatus_t queue_status =
            PC_CAT_(cusolverDnSetStr, eam)(solver_batch4[index], queues[index]);
        TORCH_CHECK(queue_status == CUSOLVER_STATUS_SUCCESS,
                    "batch4 queue binding failed: ",
                    static_cast<int>(queue_status));
    }

    TORCH_CHECK(cudaEventRecord(ready, current_q()) == cudaSuccess,
                "batch4 ready event record failed");
    for (int index = 0; index < groups; ++index) {
        TORCH_CHECK(PC_CAT_(cudaStr, eamWaitEvent)(
                        queues[index], ready, 0) == cudaSuccess,
                    "batch4 queue wait failed");
        const int offset = index * group_batch;
        const cusolverStatus_t status = cusolverDnSpotrfBatched(
            solver_batch4[index], CUBLAS_FILL_MODE_LOWER, n,
            reinterpret_cast<float**>(pointers.data_ptr<int64_t>()) + offset,
            n, info.data_ptr<int>() + offset, group_batch);
        TORCH_CHECK(status == CUSOLVER_STATUS_SUCCESS,
                    "batch4 POTRF failed: ", static_cast<int>(status));
        TORCH_CHECK(cudaEventRecord(done[index], queues[index]) == cudaSuccess,
                    "batch4 done event record failed");
    }
    for (int index = 0; index < groups; ++index) {
        TORCH_CHECK(PC_CAT_(cudaStr, eamWaitEvent)(
                        current_q(), done[index], 0) == cudaSuccess,
                    "batch4 caller wait failed");
    }
    const cudaError_t error = cudaGetLastError();
    TORCH_CHECK(error == cudaSuccess, "direct split2 launch failed: ",
                cudaGetErrorString(error));
    return raw.transpose(1, 2);
}

torch::Tensor xpotrf_bf16x9(torch::Tensor input) {
    TORCH_CHECK(input.is_cuda() && input.scalar_type() == torch::kFloat32,
                "input must be CUDA FP32");
    TORCH_CHECK(input.is_contiguous() && input.dim() == 3 &&
                input.size(0) == 1 && input.size(1) == 4096 &&
                input.size(2) == 4096,
                "input must be contiguous (1,4096,4096)");
    c10::cuda::CUDAGuard guard(input.device());
    constexpr int n = 4096;
    auto raw = torch::empty_like(input);
    auto info = torch::empty({1}, input.options().dtype(torch::kInt32));
    prepare_view<n, 16><<<dim3(1, n / 16), 256, 0, current_q()>>>(
        input.data_ptr<float>(), raw.data_ptr<float>());
    if (xsolver == nullptr) {
        const cusolverStatus_t create_status = cusolverDnCreate(&xsolver);
        TORCH_CHECK(create_status == CUSOLVER_STATUS_SUCCESS,
                    "xsolver creation failed: ",
                    static_cast<int>(create_status));
        const cusolverStatus_t params_status = cusolverDnCreateParams(&xparams);
        TORCH_CHECK(params_status == CUSOLVER_STATUS_SUCCESS,
                    "xsolver params creation failed: ",
                    static_cast<int>(params_status));
        const cusolverStatus_t math_status = cusolverDnSetMathMode(
            xsolver, CUSOLVER_FP32_EMULATED_BF16X9_MATH);
        TORCH_CHECK(math_status == CUSOLVER_STATUS_SUCCESS,
                    "xsolver math mode failed: ",
                    static_cast<int>(math_status));
    }
    const cusolverStatus_t queue_status =
        PC_CAT_(cusolverDnSetStr, eam)(xsolver, current_q());
    TORCH_CHECK(queue_status == CUSOLVER_STATUS_SUCCESS,
                "xsolver queue binding failed: ",
                static_cast<int>(queue_status));
    if (xdevice_bytes == 0) {
        const cusolverStatus_t size_status = cusolverDnXpotrf_bufferSize(
            xsolver, xparams, CUBLAS_FILL_MODE_LOWER, n,
            CUDA_R_32F, raw.data_ptr<float>(), n, CUDA_R_32F,
            &xdevice_bytes, &xhost_bytes);
        TORCH_CHECK(size_status == CUSOLVER_STATUS_SUCCESS,
                    "xpotrf workspace query failed: ",
                    static_cast<int>(size_status));
        xworkspace = torch::empty(
            {static_cast<int64_t>(xdevice_bytes)},
            input.options().dtype(torch::kUInt8));
        xhost_workspace.resize(xhost_bytes);
    }
    const cusolverStatus_t status = cusolverDnXpotrf(
        xsolver, xparams, CUBLAS_FILL_MODE_LOWER, n,
        CUDA_R_32F, raw.data_ptr<float>(), n, CUDA_R_32F,
        xworkspace.data_ptr(), xdevice_bytes,
        xhost_bytes ? xhost_workspace.data() : nullptr, xhost_bytes,
        info.data_ptr<int>());
    TORCH_CHECK(status == CUSOLVER_STATUS_SUCCESS,
                "cusolverDnXpotrf failed: ", static_cast<int>(status));
    const cudaError_t error = cudaGetLastError();
    TORCH_CHECK(error == cudaSuccess, "xpotrf launch failed: ",
                cudaGetErrorString(error));
    return raw.transpose(1, 2);
}

torch::Tensor xpotrf_bf16x9_2(torch::Tensor input) {
    TORCH_CHECK(input.is_cuda() && input.scalar_type() == torch::kFloat32,
                "input must be CUDA FP32");
    TORCH_CHECK(input.is_contiguous() && input.dim() == 3 &&
                input.size(0) == 2 && input.size(1) == input.size(2) &&
                (input.size(1) == 2048 || input.size(1) == 4096),
                "input must be contiguous batch2 n2048 or n4096");
    c10::cuda::CUDAGuard guard(input.device());
    const int n = static_cast<int>(input.size(1));
    const size_t matrix_elements = static_cast<size_t>(n) * n;
    auto raw = torch::empty_like(input);
    auto info = torch::empty({2}, input.options().dtype(torch::kInt32));
    using Queue = decltype(current_q());
    static Queue queues[2] = {nullptr, nullptr};
    for (int index = 0; index < 2; ++index) {
        if (queues[index] == nullptr) {
            const cudaError_t create_error =
                PC_CAT_(cudaStr, eamCreateWithFlags)(
                    &queues[index], 1);
            TORCH_CHECK(create_error == cudaSuccess,
                        "queue creation failed: ",
                        cudaGetErrorString(create_error));
        }
        if (xsolver2[index] == nullptr) {
            const cusolverStatus_t create_status =
                cusolverDnCreate(&xsolver2[index]);
            TORCH_CHECK(create_status == CUSOLVER_STATUS_SUCCESS,
                        "xsolver2 creation failed: ",
                        static_cast<int>(create_status));
            const cusolverStatus_t params_status =
                cusolverDnCreateParams(&xparams2[index]);
            TORCH_CHECK(params_status == CUSOLVER_STATUS_SUCCESS,
                        "xsolver2 params creation failed: ",
                        static_cast<int>(params_status));
            const cusolverStatus_t math_status = cusolverDnSetMathMode(
                xsolver2[index], CUSOLVER_FP32_EMULATED_BF16X9_MATH);
            TORCH_CHECK(math_status == CUSOLVER_STATUS_SUCCESS,
                        "xsolver2 math mode failed: ",
                        static_cast<int>(math_status));
        }
        const cusolverStatus_t queue_status =
            PC_CAT_(cusolverDnSetStr, eam)(xsolver2[index], queues[index]);
        TORCH_CHECK(queue_status == CUSOLVER_STATUS_SUCCESS,
                    "xsolver2 queue binding failed: ",
                    static_cast<int>(queue_status));
        if (xworkspace_n2[index] != n) {
            const cusolverStatus_t size_status = cusolverDnXpotrf_bufferSize(
                xsolver2[index], xparams2[index], CUBLAS_FILL_MODE_LOWER, n,
                CUDA_R_32F,
                raw.data_ptr<float>() + index * matrix_elements, n,
                CUDA_R_32F, &xdevice_bytes2[index], &xhost_bytes2[index]);
            TORCH_CHECK(size_status == CUSOLVER_STATUS_SUCCESS,
                        "xpotrf2 workspace query failed: ",
                        static_cast<int>(size_status));
            xworkspace2[index] = torch::empty(
                {static_cast<int64_t>(xdevice_bytes2[index])},
                input.options().dtype(torch::kUInt8));
            xhost_workspace2[index].resize(xhost_bytes2[index]);
            xworkspace_n2[index] = n;
        }
    }

    cudaEvent_t ready = nullptr;
    cudaEvent_t done[2] = {nullptr, nullptr};
    TORCH_CHECK(cudaEventCreateWithFlags(&ready, cudaEventDisableTiming) ==
                    cudaSuccess,
                "ready event creation failed");
    TORCH_CHECK(cudaEventRecord(ready, current_q()) == cudaSuccess,
                "ready event record failed");
    for (int index = 0; index < 2; ++index) {
        TORCH_CHECK(cudaEventCreateWithFlags(
                        &done[index], cudaEventDisableTiming) == cudaSuccess,
                    "done event creation failed");
        TORCH_CHECK(PC_CAT_(cudaStr, eamWaitEvent)(
                        queues[index], ready, 0) == cudaSuccess,
                    "queue wait failed");
        if (n == 2048) {
            prepare_view<2048, 4>
                <<<dim3(1, 2048 / 4), 256, 0, queues[index]>>>(
                    input.data_ptr<float>() + index * matrix_elements,
                    raw.data_ptr<float>() + index * matrix_elements);
        } else {
            prepare_view<4096, 4>
                <<<dim3(1, 4096 / 4), 256, 0, queues[index]>>>(
                    input.data_ptr<float>() + index * matrix_elements,
                    raw.data_ptr<float>() + index * matrix_elements);
        }
        const cusolverStatus_t status = cusolverDnXpotrf(
            xsolver2[index], xparams2[index], CUBLAS_FILL_MODE_LOWER, n,
            CUDA_R_32F,
            raw.data_ptr<float>() + index * matrix_elements, n, CUDA_R_32F,
            xworkspace2[index].data_ptr(), xdevice_bytes2[index],
            xhost_bytes2[index] ? xhost_workspace2[index].data() : nullptr,
            xhost_bytes2[index], info.data_ptr<int>() + index);
        TORCH_CHECK(status == CUSOLVER_STATUS_SUCCESS,
                    "cusolverDnXpotrf2 failed: ",
                    static_cast<int>(status));
        TORCH_CHECK(cudaEventRecord(done[index], queues[index]) == cudaSuccess,
                    "done event record failed");
    }
    for (int index = 0; index < 2; ++index) {
        TORCH_CHECK(PC_CAT_(cudaStr, eamWaitEvent)(
                        current_q(), done[index], 0) == cudaSuccess,
                    "caller wait failed");
        cudaEventDestroy(done[index]);
    }
    cudaEventDestroy(ready);
    const cudaError_t error = cudaGetLastError();
    TORCH_CHECK(error == cudaSuccess, "xpotrf2 launch failed: ",
                cudaGetErrorString(error));
    return raw.transpose(1, 2);
}

torch::Tensor xpotrf_bf16x9_8(torch::Tensor input) {
    TORCH_CHECK(input.is_cuda() && input.scalar_type() == torch::kFloat32,
                "input must be CUDA FP32");
    TORCH_CHECK(input.is_contiguous() && input.dim() == 3 &&
                input.size(0) == 8 && input.size(1) == 2048 &&
                input.size(2) == 2048,
                "input must be contiguous batch8 n2048");
    c10::cuda::CUDAGuard guard(input.device());
    constexpr int n = 2048;
    constexpr size_t matrix_elements = static_cast<size_t>(n) * n;
    auto raw = torch::empty_like(input);
    auto info = torch::empty({8}, input.options().dtype(torch::kInt32));
    using Queue = decltype(current_q());
    static Queue queues[8] = {};
    for (int index = 0; index < 8; ++index) {
        if (queues[index] == nullptr) {
            const cudaError_t create_error =
                PC_CAT_(cudaStr, eamCreateWithFlags)(&queues[index], 1);
            TORCH_CHECK(create_error == cudaSuccess,
                        "queue8 creation failed: ",
                        cudaGetErrorString(create_error));
        }
        if (xsolver8[index] == nullptr) {
            const cusolverStatus_t create_status =
                cusolverDnCreate(&xsolver8[index]);
            TORCH_CHECK(create_status == CUSOLVER_STATUS_SUCCESS,
                        "xsolver8 creation failed: ",
                        static_cast<int>(create_status));
            const cusolverStatus_t params_status =
                cusolverDnCreateParams(&xparams8[index]);
            TORCH_CHECK(params_status == CUSOLVER_STATUS_SUCCESS,
                        "xsolver8 params creation failed: ",
                        static_cast<int>(params_status));
            const cusolverStatus_t math_status = cusolverDnSetMathMode(
                xsolver8[index], CUSOLVER_FP32_EMULATED_BF16X9_MATH);
            TORCH_CHECK(math_status == CUSOLVER_STATUS_SUCCESS,
                        "xsolver8 math mode failed: ",
                        static_cast<int>(math_status));
        }
        const cusolverStatus_t queue_status =
            PC_CAT_(cusolverDnSetStr, eam)(xsolver8[index], queues[index]);
        TORCH_CHECK(queue_status == CUSOLVER_STATUS_SUCCESS,
                    "xsolver8 queue binding failed: ",
                    static_cast<int>(queue_status));
        if (xdevice_bytes8[index] == 0) {
            const cusolverStatus_t size_status = cusolverDnXpotrf_bufferSize(
                xsolver8[index], xparams8[index], CUBLAS_FILL_MODE_LOWER, n,
                CUDA_R_32F,
                raw.data_ptr<float>() + index * matrix_elements, n,
                CUDA_R_32F, &xdevice_bytes8[index], &xhost_bytes8[index]);
            TORCH_CHECK(size_status == CUSOLVER_STATUS_SUCCESS,
                        "xpotrf8 workspace query failed: ",
                        static_cast<int>(size_status));
            xworkspace8[index] = torch::empty(
                {static_cast<int64_t>(xdevice_bytes8[index])},
                input.options().dtype(torch::kUInt8));
            xhost_workspace8[index].resize(xhost_bytes8[index]);
        }
    }

    cudaEvent_t ready = nullptr;
    cudaEvent_t done[8] = {};
    TORCH_CHECK(cudaEventCreateWithFlags(&ready, cudaEventDisableTiming) ==
                    cudaSuccess,
                "ready8 event creation failed");
    TORCH_CHECK(cudaEventRecord(ready, current_q()) == cudaSuccess,
                "ready8 event record failed");
    for (int index = 0; index < 8; ++index) {
        TORCH_CHECK(cudaEventCreateWithFlags(
                        &done[index], cudaEventDisableTiming) == cudaSuccess,
                    "done8 event creation failed");
        TORCH_CHECK(PC_CAT_(cudaStr, eamWaitEvent)(
                        queues[index], ready, 0) == cudaSuccess,
                    "queue8 wait failed");
        prepare_view<2048, 4>
            <<<dim3(1, 2048 / 4), 256, 0, queues[index]>>>(
                input.data_ptr<float>() + index * matrix_elements,
                raw.data_ptr<float>() + index * matrix_elements);
        const cusolverStatus_t status = cusolverDnXpotrf(
            xsolver8[index], xparams8[index], CUBLAS_FILL_MODE_LOWER, n,
            CUDA_R_32F,
            raw.data_ptr<float>() + index * matrix_elements, n, CUDA_R_32F,
            xworkspace8[index].data_ptr(), xdevice_bytes8[index],
            xhost_bytes8[index] ? xhost_workspace8[index].data() : nullptr,
            xhost_bytes8[index], info.data_ptr<int>() + index);
        TORCH_CHECK(status == CUSOLVER_STATUS_SUCCESS,
                    "cusolverDnXpotrf8 failed: ", static_cast<int>(status));
        TORCH_CHECK(cudaEventRecord(done[index], queues[index]) == cudaSuccess,
                    "done8 event record failed");
    }
    for (int index = 0; index < 8; ++index) {
        TORCH_CHECK(PC_CAT_(cudaStr, eamWaitEvent)(
                        current_q(), done[index], 0) == cudaSuccess,
                    "caller8 wait failed");
        cudaEventDestroy(done[index]);
    }
    cudaEventDestroy(ready);
    const cudaError_t error = cudaGetLastError();
    TORCH_CHECK(error == cudaSuccess, "xpotrf8 launch failed: ",
                cudaGetErrorString(error));
    return raw.transpose(1, 2);
}

torch::Tensor xpotrf_bf16x9_4(torch::Tensor input) {
    TORCH_CHECK(input.is_cuda() && input.scalar_type() == torch::kFloat32,
                "input must be CUDA FP32");
    TORCH_CHECK(input.is_contiguous() && input.dim() == 3 &&
                input.size(0) == 4 && input.size(1) == 1024 &&
                input.size(2) == 1024,
                "input must be contiguous batch4 n1024");
    c10::cuda::CUDAGuard guard(input.device());
    constexpr int n = 1024;
    constexpr size_t matrix_elements = static_cast<size_t>(n) * n;
    auto raw = torch::empty_like(input);
    auto info = torch::empty({4}, input.options().dtype(torch::kInt32));
    using Queue = decltype(current_q());
    static Queue queues[4] = {};
    for (int index = 0; index < 4; ++index) {
        if (queues[index] == nullptr) {
            const cudaError_t create_error =
                PC_CAT_(cudaStr, eamCreateWithFlags)(&queues[index], 1);
            TORCH_CHECK(create_error == cudaSuccess,
                        "queue4 creation failed: ",
                        cudaGetErrorString(create_error));
        }
        if (xsolver4[index] == nullptr) {
            const cusolverStatus_t create_status =
                cusolverDnCreate(&xsolver4[index]);
            TORCH_CHECK(create_status == CUSOLVER_STATUS_SUCCESS,
                        "xsolver4 creation failed: ",
                        static_cast<int>(create_status));
            const cusolverStatus_t params_status =
                cusolverDnCreateParams(&xparams4[index]);
            TORCH_CHECK(params_status == CUSOLVER_STATUS_SUCCESS,
                        "xsolver4 params creation failed: ",
                        static_cast<int>(params_status));
            const cusolverStatus_t math_status = cusolverDnSetMathMode(
                xsolver4[index], CUSOLVER_FP32_EMULATED_BF16X9_MATH);
            TORCH_CHECK(math_status == CUSOLVER_STATUS_SUCCESS,
                        "xsolver4 math mode failed: ",
                        static_cast<int>(math_status));
        }
        const cusolverStatus_t queue_status =
            PC_CAT_(cusolverDnSetStr, eam)(xsolver4[index], queues[index]);
        TORCH_CHECK(queue_status == CUSOLVER_STATUS_SUCCESS,
                    "xsolver4 queue binding failed: ",
                    static_cast<int>(queue_status));
        if (xdevice_bytes4[index] == 0) {
            const cusolverStatus_t size_status = cusolverDnXpotrf_bufferSize(
                xsolver4[index], xparams4[index], CUBLAS_FILL_MODE_LOWER, n,
                CUDA_R_32F,
                raw.data_ptr<float>() + index * matrix_elements, n,
                CUDA_R_32F, &xdevice_bytes4[index], &xhost_bytes4[index]);
            TORCH_CHECK(size_status == CUSOLVER_STATUS_SUCCESS,
                        "xpotrf4 workspace query failed: ",
                        static_cast<int>(size_status));
            xworkspace4[index] = torch::empty(
                {static_cast<int64_t>(xdevice_bytes4[index])},
                input.options().dtype(torch::kUInt8));
            xhost_workspace4[index].resize(xhost_bytes4[index]);
        }
    }

    cudaEvent_t ready = nullptr;
    cudaEvent_t done[4] = {};
    TORCH_CHECK(cudaEventCreateWithFlags(&ready, cudaEventDisableTiming) ==
                    cudaSuccess,
                "ready4 event creation failed");
    TORCH_CHECK(cudaEventRecord(ready, current_q()) == cudaSuccess,
                "ready4 event record failed");
    for (int index = 0; index < 4; ++index) {
        TORCH_CHECK(cudaEventCreateWithFlags(
                        &done[index], cudaEventDisableTiming) == cudaSuccess,
                    "done4 event creation failed");
        TORCH_CHECK(PC_CAT_(cudaStr, eamWaitEvent)(
                        queues[index], ready, 0) == cudaSuccess,
                    "queue4 wait failed");
        prepare_view<1024, 4>
            <<<dim3(1, 1024 / 4), 256, 0, queues[index]>>>(
                input.data_ptr<float>() + index * matrix_elements,
                raw.data_ptr<float>() + index * matrix_elements);
        const cusolverStatus_t status = cusolverDnXpotrf(
            xsolver4[index], xparams4[index], CUBLAS_FILL_MODE_LOWER, n,
            CUDA_R_32F,
            raw.data_ptr<float>() + index * matrix_elements, n, CUDA_R_32F,
            xworkspace4[index].data_ptr(), xdevice_bytes4[index],
            xhost_bytes4[index] ? xhost_workspace4[index].data() : nullptr,
            xhost_bytes4[index], info.data_ptr<int>() + index);
        TORCH_CHECK(status == CUSOLVER_STATUS_SUCCESS,
                    "cusolverDnXpotrf4 failed: ", static_cast<int>(status));
        TORCH_CHECK(cudaEventRecord(done[index], queues[index]) == cudaSuccess,
                    "done4 event record failed");
    }
    for (int index = 0; index < 4; ++index) {
        TORCH_CHECK(PC_CAT_(cudaStr, eamWaitEvent)(
                        current_q(), done[index], 0) == cudaSuccess,
                    "caller4 wait failed");
        cudaEventDestroy(done[index]);
    }
    cudaEventDestroy(ready);
    const cudaError_t error = cudaGetLastError();
    TORCH_CHECK(error == cudaSuccess, "xpotrf4 launch failed: ",
                cudaGetErrorString(error));
    return raw.transpose(1, 2);
}

torch::Tensor xpotrf_bf16x9_16(torch::Tensor input) {
    TORCH_CHECK(input.is_cuda() && input.scalar_type() == torch::kFloat32,
                "input must be CUDA FP32");
    TORCH_CHECK(input.is_contiguous() && input.dim() == 3 &&
                input.size(0) == 16 && input.size(1) == 512 &&
                input.size(2) == 512,
                "input must be contiguous batch16 n512");
    c10::cuda::CUDAGuard guard(input.device());
    constexpr int batch = 16;
    constexpr int n = 512;
    constexpr size_t matrix_elements = static_cast<size_t>(n) * n;
    auto raw = torch::empty_like(input);
    auto info = torch::empty({batch}, input.options().dtype(torch::kInt32));
    using Queue = decltype(current_q());
    static Queue queues[batch] = {};
    static cudaEvent_t ready = nullptr;
    static cudaEvent_t done[batch] = {};
    if (ready == nullptr) {
        TORCH_CHECK(cudaEventCreateWithFlags(
                        &ready, cudaEventDisableTiming) == cudaSuccess,
                    "ready16 event creation failed");
    }
    for (int index = 0; index < batch; ++index) {
        if (queues[index] == nullptr) {
            const cudaError_t create_error =
                PC_CAT_(cudaStr, eamCreateWithFlags)(&queues[index], 1);
            TORCH_CHECK(create_error == cudaSuccess,
                        "queue16 creation failed: ",
                        cudaGetErrorString(create_error));
        }
        if (done[index] == nullptr) {
            TORCH_CHECK(cudaEventCreateWithFlags(
                            &done[index], cudaEventDisableTiming) ==
                            cudaSuccess,
                        "done16 event creation failed");
        }
        if (xsolver16[index] == nullptr) {
            const cusolverStatus_t create_status =
                cusolverDnCreate(&xsolver16[index]);
            TORCH_CHECK(create_status == CUSOLVER_STATUS_SUCCESS,
                        "xsolver16 creation failed: ",
                        static_cast<int>(create_status));
            const cusolverStatus_t params_status =
                cusolverDnCreateParams(&xparams16[index]);
            TORCH_CHECK(params_status == CUSOLVER_STATUS_SUCCESS,
                        "xsolver16 params creation failed: ",
                        static_cast<int>(params_status));
            const cusolverStatus_t math_status = cusolverDnSetMathMode(
                xsolver16[index], CUSOLVER_FP32_EMULATED_BF16X9_MATH);
            TORCH_CHECK(math_status == CUSOLVER_STATUS_SUCCESS,
                        "xsolver16 math mode failed: ",
                        static_cast<int>(math_status));
        }
        const cusolverStatus_t queue_status =
            PC_CAT_(cusolverDnSetStr, eam)(xsolver16[index], queues[index]);
        TORCH_CHECK(queue_status == CUSOLVER_STATUS_SUCCESS,
                    "xsolver16 queue binding failed: ",
                    static_cast<int>(queue_status));
        if (xdevice_bytes16[index] == 0) {
            const cusolverStatus_t size_status = cusolverDnXpotrf_bufferSize(
                xsolver16[index], xparams16[index], CUBLAS_FILL_MODE_LOWER, n,
                CUDA_R_32F,
                raw.data_ptr<float>() + index * matrix_elements, n,
                CUDA_R_32F, &xdevice_bytes16[index], &xhost_bytes16[index]);
            TORCH_CHECK(size_status == CUSOLVER_STATUS_SUCCESS,
                        "xpotrf16 workspace query failed: ",
                        static_cast<int>(size_status));
            xworkspace16[index] = torch::empty(
                {static_cast<int64_t>(xdevice_bytes16[index])},
                input.options().dtype(torch::kUInt8));
            xhost_workspace16[index].resize(xhost_bytes16[index]);
        }
    }

    TORCH_CHECK(cudaEventRecord(ready, current_q()) == cudaSuccess,
                "ready16 event record failed");
    for (int index = 0; index < batch; ++index) {
        TORCH_CHECK(PC_CAT_(cudaStr, eamWaitEvent)(
                        queues[index], ready, 0) == cudaSuccess,
                    "queue16 wait failed");
        prepare_view<512, 32>
            <<<dim3(1, 512 / 32), 256, 0, queues[index]>>>(
                input.data_ptr<float>() + index * matrix_elements,
                raw.data_ptr<float>() + index * matrix_elements);
        const cusolverStatus_t status = cusolverDnXpotrf(
            xsolver16[index], xparams16[index], CUBLAS_FILL_MODE_LOWER, n,
            CUDA_R_32F,
            raw.data_ptr<float>() + index * matrix_elements, n, CUDA_R_32F,
            xworkspace16[index].data_ptr(), xdevice_bytes16[index],
            xhost_bytes16[index] ? xhost_workspace16[index].data() : nullptr,
            xhost_bytes16[index], info.data_ptr<int>() + index);
        TORCH_CHECK(status == CUSOLVER_STATUS_SUCCESS,
                    "cusolverDnXpotrf16 failed: ", static_cast<int>(status));
        TORCH_CHECK(cudaEventRecord(done[index], queues[index]) == cudaSuccess,
                    "done16 event record failed");
    }
    for (int index = 0; index < batch; ++index) {
        TORCH_CHECK(PC_CAT_(cudaStr, eamWaitEvent)(
                        current_q(), done[index], 0) == cudaSuccess,
                    "caller16 wait failed");
    }
    const cudaError_t error = cudaGetLastError();
    TORCH_CHECK(error == cudaSuccess, "xpotrf16 launch failed: ",
                cudaGetErrorString(error));
    return raw.transpose(1, 2);
}

namespace {

namespace sp_cg = cooperative_groups;
namespace sp_wmma = nvcuda::wmma;

constexpr int sp_nb = 32;
using sp_accum_fragment =
    sp_wmma::fragment<sp_wmma::accumulator, 16, 16, 16, float>;
using sp_left_fragment = sp_wmma::fragment<
    sp_wmma::matrix_a, 16, 16, 16, __half, sp_wmma::row_major>;
using sp_right_fragment = sp_wmma::fragment<
    sp_wmma::matrix_b, 16, 16, 16, __half, sp_wmma::col_major>;
using sp_right_row_fragment = sp_wmma::fragment<
    sp_wmma::matrix_b, 16, 16, 16, __half, sp_wmma::row_major>;

__device__ __forceinline__ float sp_rsqrt_nr(float value) {
    float reciprocal;
    asm("rsqrt.approx.f32 %0, %1;" : "=f"(reciprocal) : "f"(value));
    return reciprocal;
}

template <int SP_N, int SP_CTAS, int SP_THREADS, int SP_RANKK, int SP_PAIR,
          int SP_GROUP, bool SP_EXTERNAL_UPDATE = false,
          bool SP_FRONTIER_PIPELINE = false, int SP_MIN_BLOCKS = 1>
__global__ void __launch_bounds__(SP_THREADS, SP_MIN_BLOCKS)
sp_cluster_potrf1024(
    const float* __restrict__ input,
    float* __restrict__ output,
    __half* __restrict__ panel_input,
    __half* __restrict__ panel_half,
    __half* __restrict__ inverse_half,
    int stage_start) {
    constexpr int sp_n = SP_N;
    constexpr int sp_rankk = SP_RANKK;
    constexpr int sp_pair = SP_PAIR;
    constexpr int sp_group = SP_GROUP;
    constexpr int sp_threads = SP_THREADS;
    constexpr int sp_ctas = SP_CTAS;
    constexpr int sp_warps = sp_threads / 32;
    sp_cg::cluster_group cluster = sp_cg::this_cluster();
    const int rank = static_cast<int>(cluster.block_rank());
    const int matrix = static_cast<int>(blockIdx.x) / sp_ctas;
    const int tid = static_cast<int>(threadIdx.x);
    const int lane = tid & 31;
    const int warp = tid >> 5;
    const int cluster_thread = rank * sp_threads + tid;
    const int cluster_warp = rank * sp_warps + warp;
    constexpr int matrix_elements = sp_n * sp_n;
    constexpr int input_panel_elements = sp_n * sp_nb;
    constexpr int pair_panel_elements = sp_n * sp_pair;
    const float* src = input + static_cast<size_t>(matrix) * matrix_elements;
    float* dst = output + static_cast<size_t>(matrix) * matrix_elements;
    __half* hi = panel_input +
        static_cast<size_t>(matrix) * input_panel_elements;
    __half* hp = panel_half +
        static_cast<size_t>(matrix) * pair_panel_elements;
    __half* ih = inverse_half + static_cast<size_t>(matrix) * sp_nb * sp_nb;
    __shared__ float diagonal[sp_nb * sp_nb];
    __shared__ float panel_store[sp_warps * 2 * 16 * 16];

    if (!SP_EXTERNAL_UPDATE || stage_start == 0) {
        const float4* src4 = reinterpret_cast<const float4*>(src);
        float4* dst4 = reinterpret_cast<float4*>(dst);
        constexpr bool direct_lower_init =
            SP_N == 512 && SP_EXTERNAL_UPDATE && SP_MIN_BLOCKS >= 3;
        bool initialize_full = true;
        if constexpr (direct_lower_init) {
            initialize_full = gridDim.x != 640;
            if (!initialize_full) {
                constexpr int vectors_per_row = sp_n / 4;
                for (int row = cluster_warp; row < sp_n;
                     row += sp_ctas * sp_warps) {
                    const int last_vector = row / 4;
                    for (int vector_col = lane; vector_col <= last_vector;
                         vector_col += 32) {
                        const int index = row * vectors_per_row + vector_col;
                        float4 value = src4[index];
                        if (vector_col == last_vector) {
                            const int col = 4 * vector_col;
                            if (col + 1 > row) value.y = 0.0f;
                            if (col + 2 > row) value.z = 0.0f;
                            if (col + 3 > row) value.w = 0.0f;
                        }
                        dst4[index] = value;
                    }
                }
            }
        }
        if (initialize_full) {
            for (int index = cluster_thread; index < matrix_elements / 4;
                 index += sp_ctas * sp_threads) {
                constexpr int vectors_per_row = sp_n / 4;
                const int row = index / vectors_per_row;
                const int vector_col = index - row * vectors_per_row;
                const int col = 4 * vector_col;
                float4 value = make_float4(0.0f, 0.0f, 0.0f, 0.0f);
                if (col <= row) {
                    value = src4[index];
                    if (col + 1 > row) value.y = 0.0f;
                    if (col + 2 > row) value.z = 0.0f;
                    if (col + 3 > row) value.w = 0.0f;
                }
                dst4[index] = value;
            }
        }
    }
    cluster.sync();

    const int first_start = SP_EXTERNAL_UPDATE ? stage_start : 0;
    const int stop_start = SP_EXTERNAL_UPDATE
        ? min(stage_start + sp_rankk, sp_n) : sp_n;
    for (int start = first_start; start < stop_start; start += sp_nb) {
        const int end = start + sp_nb;
        const int phase = SP_EXTERNAL_UPDATE
            ? (start - stage_start) / sp_nb
            : (start / sp_nb) % (sp_rankk / sp_nb);
        const int phase_offset = phase * sp_nb;
        const int panel_count = (sp_n - end) * sp_nb;
        if (rank == 0 && warp == 0) {
            constexpr bool blocked_factor =
                (SP_N == 512 && SP_MIN_BLOCKS >= 3) ||
                (SP_N == 1024 && SP_EXTERNAL_UPDATE);
            constexpr bool high_only_factor =
                (SP_N == 512 && SP_MIN_BLOCKS >= 3) ||
                (SP_N == 1024 && SP_EXTERNAL_UPDATE);
            if constexpr (blocked_factor) {
                constexpr int factor_tile = 16;
                volatile float* factor_shared = diagonal;
                #pragma unroll
                for (int base = 0; base < sp_nb; base += factor_tile) {
                    if constexpr (blocked_factor) {
                        if (base == factor_tile) {
                            __half* factor_high =
                                reinterpret_cast<__half*>(panel_store);
                            __half* factor_low = factor_high + 16 * 16;
                            for (int index = lane; index < 16 * 16;
                                 index += 32) {
                                const int row = 16 + index / 16;
                                const int col = index % 16;
                                const float value =
                                    factor_shared[row * sp_nb + col];
                                const __half high = __float2half_rn(value);
                                factor_high[index] = high;
                                if constexpr (!high_only_factor) {
                                    factor_low[index] = __float2half_rn(
                                        value - __half2float(high));
                                }
                            }
                            __syncwarp();
                            {
                                sp_accum_fragment schur;
                                sp_wmma::load_matrix_sync(
                                    schur,
                                    dst + (start + 16) * sp_n + start + 16,
                                    sp_n, sp_wmma::mem_row_major);
                                sp_left_fragment left;
                                sp_right_fragment right;
                                sp_wmma::load_matrix_sync(
                                    left, factor_high, 16);
                                #pragma unroll
                                for (int element = 0;
                                     element < left.num_elements; ++element) {
                                    left.x[element] = __hneg(left.x[element]);
                                }
                                sp_wmma::load_matrix_sync(
                                    right, factor_high, 16);
                                sp_wmma::mma_sync(schur, left, right, schur);
                                if constexpr (!high_only_factor) {
                                    sp_wmma::load_matrix_sync(
                                        right, factor_low, 16);
                                    sp_wmma::mma_sync(
                                        schur, left, right, schur);
                                    sp_wmma::load_matrix_sync(
                                        left, factor_low, 16);
                                    #pragma unroll
                                    for (int element = 0;
                                         element < left.num_elements;
                                         ++element) {
                                        left.x[element] =
                                            __hneg(left.x[element]);
                                    }
                                    sp_wmma::load_matrix_sync(
                                        right, factor_high, 16);
                                    sp_wmma::mma_sync(
                                        schur, left, right, schur);
                                }
                                sp_wmma::store_matrix_sync(
                                    panel_store, schur, 16,
                                    sp_wmma::mem_row_major);
                            }
                            __syncwarp();
                        }
                    }
                    float factor_chunk[factor_tile];
                    #pragma unroll
                    for (int q = 0; q < factor_tile; ++q) {
                        if constexpr (blocked_factor) {
                            factor_chunk[q] = base == factor_tile
                                ? ((lane >= 16)
                                    ? panel_store[(lane - 16) * 16 + q]
                                    : 0.0f)
                                : dst[(start + lane) * sp_n + start + q];
                        } else {
                            factor_chunk[q] = dst[(start + lane) * sp_n +
                                                  start + base + q];
                        }
                    }
                    #pragma unroll
                    for (int q = 0; q < factor_tile; ++q) {
                        const int k = base + q;
                        float value = factor_chunk[q];
                        float diagonal_reciprocal = 0.0f;
                        if (lane == k) {
                            if constexpr (!blocked_factor) {
                                #pragma unroll
                                for (int p = 0; p < base; ++p) {
                                    const float x =
                                        factor_shared[lane * sp_nb + p];
                                    value = fmaf(-x, x, value);
                                }
                            }
                            #pragma unroll
                            for (int p = 0; p < q; ++p) {
                                const float x = factor_chunk[p];
                                value = fmaf(-x, x, value);
                            }
                            value = fmaxf(value, 1.0e-20f);
                            if constexpr (SP_N >= 512) {
                                diagonal_reciprocal = sp_rsqrt_nr(value);
                                value *= diagonal_reciprocal;
                            } else {
                                value = sqrtf(value);
                                diagonal_reciprocal = 1.0f / value;
                            }
                            factor_chunk[q] = value;
                        }
                        diagonal_reciprocal = __shfl_sync(
                            0xffffffffu, diagonal_reciprocal, k);
                        if constexpr (!blocked_factor) {
                            if (lane > k) {
                                #pragma unroll
                                for (int p = 0; p < base; ++p) {
                                    value = fmaf(
                                        -factor_shared[lane * sp_nb + p],
                                        factor_shared[k * sp_nb + p], value);
                                }
                            }
                        }
                        #pragma unroll
                        for (int p = 0; p < q; ++p) {
                            const float pivot = __shfl_sync(
                                0xffffffffu, factor_chunk[p], k);
                            if (lane > k) {
                                value = fmaf(-factor_chunk[p], pivot, value);
                            }
                        }
                        if (lane > k) {
                            factor_chunk[q] = value * diagonal_reciprocal;
                        }
                    }
                    #pragma unroll
                    for (int q = 0; q < factor_tile; ++q) {
                        const int col = base + q;
                        if (lane >= col) {
                            const float value = factor_chunk[q];
                            factor_shared[lane * sp_nb + col] = value;
                            dst[(start + lane) * sp_n + start + col] = value;
                        }
                    }
                    __syncwarp();
                }
            } else {
            float factor_row[sp_nb];
            #pragma unroll
            for (int col = 0; col < sp_nb; ++col) {
                factor_row[col] =
                    dst[(start + lane) * sp_n + start + col];
            }
            #pragma unroll
            for (int k = 0; k < sp_nb; ++k) {
                float value = factor_row[k];
                float diagonal_reciprocal = 0.0f;
                if (lane == k) {
                    #pragma unroll
                    for (int p = 0; p < k; ++p) {
                        const float x = factor_row[p];
                        value = fmaf(-x, x, value);
                    }
                    value = fmaxf(value, 1.0e-20f);
                    if constexpr (SP_N >= 512) {
                        diagonal_reciprocal = sp_rsqrt_nr(value);
                        value *= diagonal_reciprocal;
                    } else {
                        value = sqrtf(value);
                        diagonal_reciprocal = 1.0f / value;
                    }
                    factor_row[k] = value;
                }
                diagonal_reciprocal = __shfl_sync(
                    0xffffffffu, diagonal_reciprocal, k);
                if (lane > k) {
                    value = factor_row[k];
                }
                #pragma unroll
                for (int p = 0; p < k; ++p) {
                    const float pivot = __shfl_sync(
                        0xffffffffu, factor_row[p], k);
                    if (lane > k) {
                        value = fmaf(-factor_row[p], pivot, value);
                    }
                }
                if (lane > k) {
                    factor_row[k] = value * diagonal_reciprocal;
                }
            }
            #pragma unroll
            for (int col = 0; col < sp_nb; ++col) {
                if (lane >= col) {
                    dst[(start + lane) * sp_n + start + col] =
                        factor_row[col];
                }
            }
            }
        }
        if (end < sp_n && !(rank == 0 && warp == 0)) {
            if (SP_FRONTIER_PIPELINE && phase > 0) {
                constexpr int worker_warps = sp_ctas * sp_warps - 1;
                const int worker_warp = cluster_warp - 1;
                const int active_k = phase * sp_nb;
                const int row_tiles = (sp_n - end) / 16;
                for (int tile_row = worker_warp; tile_row < row_tiles;
                     tile_row += worker_warps) {
                    const int row = end + 16 * tile_row;
                    sp_accum_fragment accum[2];
                    #pragma unroll
                    for (int q = 0; q < 2; ++q) {
                        sp_wmma::load_matrix_sync(
                            accum[q],
                            dst + row * sp_n + start + 16 * q,
                            sp_n, sp_wmma::mem_row_major);
                    }
                    #pragma unroll
                    for (int k = 0; k < active_k; k += 16) {
                        sp_left_fragment left;
                        sp_wmma::load_matrix_sync(
                            left, hp + row * sp_pair + k, sp_pair);
                        #pragma unroll
                        for (int element = 0;
                             element < left.num_elements; ++element) {
                            left.x[element] = __hneg(left.x[element]);
                        }
                        #pragma unroll
                        for (int q = 0; q < 2; ++q) {
                            sp_right_fragment right;
                            sp_wmma::load_matrix_sync(
                                right,
                                hp + (start + 16 * q) * sp_pair + k,
                                sp_pair);
                            sp_wmma::mma_sync(
                                accum[q], left, right, accum[q]);
                        }
                    }
                    #pragma unroll
                    for (int q = 0; q < 2; ++q) {
                        float* tile = panel_store +
                            (warp * 2 + q) * 16 * 16;
                        sp_wmma::store_matrix_sync(
                            tile, accum[q], 16,
                            sp_wmma::mem_row_major);
                        __syncwarp();
                        for (int index = lane; index < 16 * 16;
                             index += 32) {
                            const int local_row = index / 16;
                            const int local_col = index % 16;
                            const float value = tile[index];
                            hi[(row + local_row) * sp_nb +
                               q * 16 + local_col] =
                                __float2half_rn(value);
                        }
                        __syncwarp();
                    }
                }
            } else {
                constexpr int reserved = 32;
                constexpr int workers = sp_ctas * sp_threads - reserved;
                const int worker = (rank == 0)
                    ? tid - reserved : sp_threads - reserved + tid;
                for (int index = worker; index < panel_count;
                     index += workers) {
                    const int row = end + index / sp_nb;
                    const int col = index % sp_nb;
                    hi[row * sp_nb + col] =
                        __float2half_rn(dst[row * sp_n + start + col]);
                }
            }
        }
        cluster.sync();
        if (end == sp_n) break;
        if (tid < sp_nb) {
            diagonal[tid] = 1.0f /
                dst[(start + tid) * sp_n + start + tid];
        }
        __syncthreads();

        if constexpr (SP_CTAS == 0) {
        if (start >= sp_n - 4 * sp_nb) {
            const int inverse_row = cluster_thread / sp_nb;
            const int inverse_col = cluster_thread % sp_nb;
            float inverse_value = 0.0f;
            if (inverse_col <= inverse_row) {
                const float inverse_row_diagonal = diagonal[inverse_row];
                if (inverse_col == inverse_row) {
                    inverse_value = inverse_row_diagonal;
                } else {
                    const float inverse_col_diagonal = diagonal[inverse_col];
                    inverse_value = -dst[(start + inverse_row) * sp_n +
                                         start + inverse_col];
                    #pragma unroll
                    for (int middle = inverse_col + 1;
                         middle < inverse_row; ++middle) {
                        inverse_value = fmaf(
                            dst[(start + inverse_row) * sp_n +
                                start + middle] * diagonal[middle],
                            dst[(start + middle) * sp_n +
                                start + inverse_col],
                            inverse_value);
                    }
                    inverse_value *=
                        inverse_row_diagonal * inverse_col_diagonal;
                }
            }
            ih[inverse_row * sp_nb + inverse_col] =
                __float2half_rn(inverse_value);
        } else {
            const int inverse_col = cluster_warp;
            const int inverse_index = inverse_col + lane;
            float inverse_value = 0.0f;
            if (lane < inverse_col) {
                ih[lane * sp_nb + inverse_col] = __float2half_rn(0.0f);
            }
            #pragma unroll
            for (int inverse_row = inverse_col;
                 inverse_row < sp_nb; ++inverse_row) {
                float product = 0.0f;
                if (inverse_index < inverse_row) {
                    product =
                        dst[(start + inverse_row) * sp_n +
                            start + inverse_index] * inverse_value;
                }
                #pragma unroll
                for (int offset = 16; offset; offset >>= 1) {
                    product += __shfl_down_sync(
                        0xffffffffu, product, offset);
                }
                const float sum = __shfl_sync(0xffffffffu, product, 0);
                if (inverse_index == inverse_row) {
                    inverse_value =
                        ((inverse_row == inverse_col) ? 1.0f : 0.0f) - sum;
                    inverse_value *= diagonal[inverse_row];
                    ih[inverse_row * sp_nb + inverse_col] =
                        __float2half_rn(inverse_value);
                }
            }
        }
        } else {
            if (rank == 0) {
            constexpr int half = sp_nb / 2;
            float* inverse_a = diagonal + sp_nb;
            float* inverse_d = inverse_a + half * half;
            float* middle = inverse_d + half * half;
            const int inverse_lane = lane & 15;
            const int inverse_offset = (lane >> 4) * half;
            float* inverse_block = inverse_a + inverse_offset * half;
            #pragma unroll
            for (int inverse_base = 0; inverse_base < half;
                 inverse_base += sp_warps) {
                const int inverse_col = inverse_base + warp;
                if (inverse_col < half) {
                    const int inverse_index = inverse_col + inverse_lane;
                    float inverse_value = 0.0f;
                    if (inverse_lane < inverse_col) {
                        inverse_block[inverse_lane * half + inverse_col] =
                            0.0f;
                    }
                    #pragma unroll
                    for (int inverse_row = inverse_col;
                         inverse_row < half; ++inverse_row) {
                        float product = 0.0f;
                        if (inverse_index < inverse_row) {
                            product = dst[
                                (start + inverse_offset + inverse_row) * sp_n +
                                start + inverse_offset + inverse_index] *
                                inverse_value;
                        }
                        #pragma unroll
                        for (int offset = 8; offset; offset >>= 1) {
                            product += __shfl_down_sync(
                                0xffffffffu, product, offset, 16);
                        }
                        const float sum =
                            __shfl_sync(0xffffffffu, product, 0, 16);
                        if (inverse_index == inverse_row) {
                            const float identity =
                                (inverse_row == inverse_col) ? 1.0f : 0.0f;
                            inverse_value = (identity - sum) *
                                diagonal[inverse_offset + inverse_row];
                            inverse_block[inverse_row * half + inverse_col] =
                                inverse_value;
                        }
                    }
                }
            }
            __syncthreads();
            __half* tc_a = reinterpret_cast<__half*>(panel_store);
            __half* tc_d = tc_a + half * half;
            __half* tc_c = tc_d + half * half;
            __half* tc_m = tc_c + half * half;
            if (tid < half * half) {
                const int row = tid / half;
                const int col = tid - row * half;
                tc_a[tid] = __float2half_rn(inverse_a[tid]);
                tc_d[tid] = __float2half_rn(inverse_d[tid]);
                tc_c[tid] = __float2half_rn(
                    dst[(start + half + row) * sp_n + start + col]);
            }
            __syncthreads();
            if (warp == 0) {
                sp_accum_fragment accum;
                sp_left_fragment left;
                sp_right_row_fragment right;
                sp_wmma::fill_fragment(accum, 0.0f);
                sp_wmma::load_matrix_sync(left, tc_d, half);
                sp_wmma::load_matrix_sync(right, tc_c, half);
                sp_wmma::mma_sync(accum, left, right, accum);
                sp_wmma::store_matrix_sync(
                    middle, accum, half, sp_wmma::mem_row_major);
            }
            __syncthreads();
            if (tid < half * half) {
                tc_m[tid] = __float2half_rn(middle[tid]);
            }
            __syncthreads();
            if (warp == 0) {
                sp_accum_fragment accum;
                sp_left_fragment left;
                sp_right_row_fragment right;
                sp_wmma::fill_fragment(accum, 0.0f);
                sp_wmma::load_matrix_sync(left, tc_m, half);
                sp_wmma::load_matrix_sync(right, tc_a, half);
                sp_wmma::mma_sync(accum, left, right, accum);
                sp_wmma::store_matrix_sync(
                    middle, accum, half, sp_wmma::mem_row_major);
            }
            __syncthreads();
            if (tid < half * half) {
                const int row = tid / half;
                const int col = tid - row * half;
                ih[row * sp_nb + col] = tc_a[tid];
                ih[row * sp_nb + half + col] = __float2half_rn(0.0f);
                ih[(half + row) * sp_nb + col] =
                    __float2half_rn(-middle[tid]);
                ih[(half + row) * sp_nb + half + col] = tc_d[tid];
            }
            __syncthreads();
            }
        }
        cluster.sync();

        const int panel_row_tiles = (sp_n - end) / 16;
        for (int tile_row = cluster_warp; tile_row < panel_row_tiles;
             tile_row += sp_ctas * sp_warps) {
            const int row = end + 16 * tile_row;
            sp_accum_fragment accum[2];
            sp_wmma::fill_fragment(accum[0], 0.0f);
            sp_wmma::fill_fragment(accum[1], 0.0f);
            #pragma unroll
            for (int k = 0; k < sp_nb; k += 16) {
                sp_left_fragment left;
                sp_wmma::load_matrix_sync(
                    left, hi + row * sp_nb + k, sp_nb);
                #pragma unroll
                for (int q = 0; q < 2; ++q) {
                    sp_right_fragment right;
                    sp_wmma::load_matrix_sync(
                        right, ih + q * 16 * sp_nb + k, sp_nb);
                    sp_wmma::mma_sync(accum[q], left, right, accum[q]);
                }
            }
            #pragma unroll
            for (int q = 0; q < 2; ++q) {
                float* tile = panel_store + (warp * 2 + q) * 16 * 16;
                sp_wmma::store_matrix_sync(
                    tile, accum[q], 16, sp_wmma::mem_row_major);
                __syncwarp();
                for (int index = lane; index < 16 * 16; index += 32) {
                    const int local_row = index / 16;
                    const int local_col = index % 16;
                    const float value = tile[index];
                    dst[(row + local_row) * sp_n + start + q * 16 + local_col] =
                        value;
                    hp[(row + local_row) * sp_pair + phase_offset +
                       q * 16 + local_col] =
                        __float2half_rn(value);
                }
                __syncwarp();
            }
        }
        cluster.sync();

        if (phase < (sp_rankk / sp_nb) - 1) {
            const int active_k = (phase + 1) * sp_nb;
            const int row_tiles = (sp_n - end) / 16;
            if constexpr (SP_FRONTIER_PIPELINE) {
                if (rank == 0 && warp == 0) {
                    #pragma unroll
                    for (int tile_row = 0; tile_row < 2; ++tile_row) {
                        const int row = end + 16 * tile_row;
                        sp_accum_fragment accum[2];
                        #pragma unroll
                        for (int q = 0; q < 2; ++q) {
                            if (q <= tile_row) {
                                sp_wmma::load_matrix_sync(
                                    accum[q],
                                    dst + row * sp_n + end + 16 * q,
                                    sp_n, sp_wmma::mem_row_major);
                            }
                        }
                        #pragma unroll
                        for (int k = 0; k < active_k; k += 16) {
                            sp_left_fragment left;
                            sp_wmma::load_matrix_sync(
                                left, hp + row * sp_pair + k, sp_pair);
                            #pragma unroll
                            for (int element = 0;
                                 element < left.num_elements; ++element) {
                                left.x[element] = __hneg(left.x[element]);
                            }
                            #pragma unroll
                            for (int q = 0; q < 2; ++q) {
                                if (q <= tile_row) {
                                    sp_right_fragment right;
                                    sp_wmma::load_matrix_sync(
                                        right,
                                        hp + (end + 16 * q) * sp_pair + k,
                                        sp_pair);
                                    sp_wmma::mma_sync(
                                        accum[q], left, right, accum[q]);
                                }
                            }
                        }
                        #pragma unroll
                        for (int q = 0; q < 2; ++q) {
                            if (q <= tile_row) {
                                sp_wmma::store_matrix_sync(
                                    dst + row * sp_n + end + 16 * q,
                                    accum[q], sp_n,
                                    sp_wmma::mem_row_major);
                            }
                        }
                    }
                    __syncwarp();
                }
                continue;
            }
            for (int tile_row = cluster_warp; tile_row < row_tiles;
                 tile_row += sp_ctas * sp_warps) {
                const int row = end + 16 * tile_row;
                sp_accum_fragment accum[2];
                #pragma unroll
                for (int q = 0; q < 2; ++q) {
                    if (q <= tile_row) {
                        sp_wmma::load_matrix_sync(
                            accum[q], dst + row * sp_n + end + 16 * q,
                            sp_n, sp_wmma::mem_row_major);
                    }
                }
                #pragma unroll
                for (int k = 0; k < active_k; k += 16) {
                    sp_left_fragment left;
                    sp_wmma::load_matrix_sync(
                        left, hp + row * sp_pair + k,
                        sp_pair);
                    #pragma unroll
                    for (int element = 0; element < left.num_elements;
                         ++element) {
                        left.x[element] = __hneg(left.x[element]);
                    }
                    #pragma unroll
                    for (int q = 0; q < 2; ++q) {
                        if (q <= tile_row) {
                            sp_right_fragment right;
                            sp_wmma::load_matrix_sync(
                                right,
                                hp + (end + 16 * q) * sp_pair +
                                    k,
                                sp_pair);
                            sp_wmma::mma_sync(
                                accum[q], left, right, accum[q]);
                        }
                    }
                }
                #pragma unroll
                for (int q = 0; q < 2; ++q) {
                    if (q <= tile_row) {
                        sp_wmma::store_matrix_sync(
                            dst + row * sp_n + end + 16 * q,
                            accum[q], sp_n, sp_wmma::mem_row_major);
                    }
                }
            }
            cluster.sync();
            continue;
        }

        if constexpr (SP_EXTERNAL_UPDATE) {
            continue;
        }

        const int tile_count = (sp_n - end) / 16;
        int job = 0;
        for (int tile_row = 0; tile_row < tile_count; ++tile_row) {
            const int groups = tile_row / sp_group + 1;
            for (int group = 0; group < groups; ++group, ++job) {
                if (job % (sp_ctas * sp_warps) != cluster_warp) continue;
                const int row = end + 16 * tile_row;
                const int first_col = sp_group * group;
                sp_accum_fragment accum[sp_group];
                #pragma unroll
                for (int q = 0; q < sp_group; ++q) {
                    if (first_col + q <= tile_row) {
                        const int col = end + 16 * (first_col + q);
                        sp_wmma::load_matrix_sync(
                            accum[q], dst + row * sp_n + col, sp_n,
                            sp_wmma::mem_row_major);
                    }
                }
                #pragma unroll
                for (int k = 0; k < sp_rankk; k += 16) {
                    sp_left_fragment left;
                    sp_wmma::load_matrix_sync(
                        left, hp + row * sp_pair + k, sp_pair);
                    #pragma unroll
                    for (int element = 0;
                         element < left.num_elements; ++element) {
                        left.x[element] = __hneg(left.x[element]);
                    }
                    #pragma unroll
                    for (int q = 0; q < sp_group; ++q) {
                        if (first_col + q <= tile_row) {
                            const int col = end + 16 * (first_col + q);
                            sp_right_fragment right;
                            sp_wmma::load_matrix_sync(
                                right, hp + col * sp_pair + k, sp_pair);
                            sp_wmma::mma_sync(
                                accum[q], left, right, accum[q]);
                        }
                    }
                }
                #pragma unroll
                for (int q = 0; q < sp_group; ++q) {
                    if (first_col + q <= tile_row) {
                        const int col = end + 16 * (first_col + q);
                        sp_wmma::store_matrix_sync(
                            dst + row * sp_n + col, accum[q], sp_n,
                            sp_wmma::mem_row_major);
                    }
                }
            }
        }
        cluster.sync();
    }

    if constexpr (!SP_EXTERNAL_UPDATE) {
        constexpr int diagonal_tile = 16;
        constexpr int diagonal_elements =
            (sp_n / diagonal_tile) * diagonal_tile * diagonal_tile;
        for (int index = cluster_thread; index < diagonal_elements;
             index += sp_ctas * sp_threads) {
            const int tile = index / (diagonal_tile * diagonal_tile);
            const int local = index - tile * diagonal_tile * diagonal_tile;
            const int row = local / diagonal_tile;
            const int col = local - row * diagonal_tile;
            if (col > row) {
                const int base = tile * diagonal_tile;
                dst[(base + row) * sp_n + base + col] = 0.0f;
            }
        }
    }
}

constexpr int sg_nb = 32;

template <int SG_N, int SG_RANKK, int SG_STRIDE, int SG_CTAS,
          int SG_THREADS, bool SG_FP32_PANEL, bool SG_FP32_UPDATE,
          bool SG_EXTERNAL_UPDATE = false>
__global__ void __launch_bounds__(SG_THREADS, 1) sg_grid_potrf2048(
    const float* __restrict__ input,
    float* __restrict__ output,
    __half* __restrict__ panel_input,
    __half* __restrict__ panel_half,
    __half* __restrict__ inverse_half,
    int stage_start) {
    constexpr int sg_n = SG_N;
    constexpr int sg_rankk = SG_RANKK;
    constexpr int sg_stride = SG_STRIDE;
    constexpr int sg_ctas = SG_CTAS;
    constexpr int sg_threads = SG_THREADS;
    constexpr int sg_warps = sg_threads / 32;
    sp_cg::cluster_group grid = sp_cg::this_cluster();
    const int rank = static_cast<int>(blockIdx.x) % sg_ctas;
    const int matrix = static_cast<int>(blockIdx.x) / sg_ctas;
    const int tid = static_cast<int>(threadIdx.x);
    const int lane = tid & 31;
    const int warp = tid >> 5;
    const int grid_thread = rank * sg_threads + tid;
    const int grid_warp = rank * sg_warps + warp;
    constexpr int matrix_elements = sg_n * sg_n;
    constexpr int input_panel_elements = sg_n * sg_nb;
    constexpr int rankk_panel_elements = sg_n * sg_stride;
    const float* src = input + static_cast<size_t>(matrix) * matrix_elements;
    float* dst = output + static_cast<size_t>(matrix) * matrix_elements;
    __half* hi = panel_input +
        static_cast<size_t>(matrix) * input_panel_elements;
    __half* hp = panel_half +
        static_cast<size_t>(matrix) * rankk_panel_elements;
    __half* ih = inverse_half + static_cast<size_t>(matrix) * sg_nb * sg_nb;
    __shared__ float panel_store[sg_warps * 2 * 16 * 16];
    __shared__ float panel_reciprocal[sg_nb];
    constexpr bool sg_factor_frontier_pipeline =
        SG_N == 2048 && SG_RANKK == 256 && SG_STRIDE == 288 &&
        SG_CTAS == 8 && SG_THREADS == 512 && !SG_FP32_PANEL &&
        !SG_FP32_UPDATE && SG_EXTERNAL_UPDATE;

    if (!SG_EXTERNAL_UPDATE || stage_start == 0) {
        const float4* src4 = reinterpret_cast<const float4*>(src);
        float4* dst4 = reinterpret_cast<float4*>(dst);
        for (int index = grid_thread; index < matrix_elements / 4;
             index += sg_ctas * sg_threads) {
            constexpr int vectors_per_row = sg_n / 4;
            const int row = index / vectors_per_row;
            const int vector_col = index - row * vectors_per_row;
            const int col = 4 * vector_col;
            float4 value = make_float4(0.0f, 0.0f, 0.0f, 0.0f);
            if (col <= row) {
                value = src4[index];
                if (col + 1 > row) value.y = 0.0f;
                if (col + 2 > row) value.z = 0.0f;
                if (col + 3 > row) value.w = 0.0f;
            }
            dst4[index] = value;
        }
    }
    grid.sync();

    const int first_start = SG_EXTERNAL_UPDATE ? stage_start : 0;
    const int stop_start = SG_EXTERNAL_UPDATE
        ? min(stage_start + sg_rankk, sg_n) : sg_n;
    for (int start = first_start; start < stop_start; start += sg_nb) {
        const int end = start + sg_nb;
        const int phase = SG_EXTERNAL_UPDATE
            ? (start - stage_start) / sg_nb
            : (start / sg_nb) % (sg_rankk / sg_nb);
        const int phase_offset = phase * sg_nb;
        const int panel_count = (sg_n - end) * sg_nb;
        if (rank == 0 && warp == 0) {
            if constexpr (SG_N == 256 || SG_N == 2048) {
                constexpr int factor_tile = 16;
                __half* factor_high =
                    reinterpret_cast<__half*>(panel_store);
                __half* factor_low =
                    factor_high + factor_tile * factor_tile;
                float* factor_schur = reinterpret_cast<float*>(
                    factor_low + factor_tile * factor_tile);
                #pragma unroll
                for (int base = 0; base < sg_nb; base += factor_tile) {
                    if (base == factor_tile) {
                        #pragma unroll
                        for (int group = 0; group < 2; ++group) {
                            const int vector_index = lane + 32 * group;
                            const int row = factor_tile + (vector_index >> 2);
                            const int col = 4 * (vector_index & 3);
                            const int index = 4 * vector_index;
                            const float4 value =
                                *reinterpret_cast<const float4*>(
                                    dst + (start + row) * sg_n + start + col);
                            const __half2 high01 = __floats2half2_rn(
                                value.x, value.y);
                            const __half2 high23 = __floats2half2_rn(
                                value.z, value.w);
                            *reinterpret_cast<__half2*>(factor_high + index) =
                                high01;
                            *reinterpret_cast<__half2*>(
                                factor_high + index + 2) = high23;
                            if constexpr (SG_N == 256) {
                                const float2 highf01 = __half22float2(high01);
                                const float2 highf23 = __half22float2(high23);
                                *reinterpret_cast<__half2*>(
                                    factor_low + index) = __floats2half2_rn(
                                        value.x - highf01.x,
                                        value.y - highf01.y);
                                *reinterpret_cast<__half2*>(
                                    factor_low + index + 2) =
                                        __floats2half2_rn(
                                            value.z - highf23.x,
                                            value.w - highf23.y);
                            }
                        }
                        __syncwarp();
                        sp_accum_fragment schur;
                        sp_wmma::load_matrix_sync(
                            schur,
                            dst + (start + factor_tile) * sg_n +
                                start + factor_tile,
                            sg_n, sp_wmma::mem_row_major);
                        sp_left_fragment left;
                        sp_right_fragment right;
                        sp_wmma::load_matrix_sync(
                            left, factor_high, factor_tile);
                        #pragma unroll
                        for (int element = 0; element < left.num_elements;
                             ++element) {
                            left.x[element] = __hneg(left.x[element]);
                        }
                        sp_wmma::load_matrix_sync(
                            right, factor_high, factor_tile);
                        sp_wmma::mma_sync(schur, left, right, schur);
                        if constexpr (SG_N == 256) {
                            sp_wmma::load_matrix_sync(
                                right, factor_low, factor_tile);
                            sp_wmma::mma_sync(schur, left, right, schur);
                            sp_wmma::load_matrix_sync(
                                left, factor_low, factor_tile);
                            #pragma unroll
                            for (int element = 0;
                                 element < left.num_elements; ++element) {
                                left.x[element] = __hneg(left.x[element]);
                            }
                            sp_wmma::load_matrix_sync(
                                right, factor_high, factor_tile);
                            sp_wmma::mma_sync(
                                schur, left, right, schur);
                        }
                        sp_wmma::store_matrix_sync(
                            factor_schur, schur, factor_tile,
                            sp_wmma::mem_row_major);
                        __syncwarp();
                    }

                    float factor_chunk[factor_tile];
                    #pragma unroll
                    for (int q = 0; q < factor_tile; ++q) {
                        factor_chunk[q] = base == factor_tile
                            ? ((lane >= factor_tile)
                                ? factor_schur[
                                    (lane - factor_tile) * factor_tile + q]
                                : 0.0f)
                            : dst[(start + lane) * sg_n + start + q];
                    }
                    #pragma unroll
                    for (int q = 0; q < factor_tile; ++q) {
                        const int k = base + q;
                        float value = factor_chunk[q];
                        #pragma unroll
                        for (int p = 0; p < q; ++p) {
                            const float pivot = __shfl_sync(
                                0xffffffffu, factor_chunk[p], k);
                            if (lane >= k) {
                                value = fmaf(-factor_chunk[p], pivot, value);
                            }
                        }
                        float inverse_diagonal = 0.0f;
                        if (lane == k) {
                            value = fmaxf(value, 1.0e-20f);
                            inverse_diagonal = sp_rsqrt_nr(value);
                        }
                        inverse_diagonal = __shfl_sync(
                            0xffffffffu, inverse_diagonal, k);
                        if (lane >= k) {
                            factor_chunk[q] = value * inverse_diagonal;
                        }
                    }
                    #pragma unroll
                    for (int q = 0; q < factor_tile; ++q) {
                        const int col = base + q;
                        if (lane >= col) {
                            dst[(start + lane) * sg_n + start + col] =
                                factor_chunk[q];
                        }
                    }
                    __syncwarp();
                }
            } else {
                float factor_row[sg_nb];
                #pragma unroll
                for (int col = 0; col < sg_nb; ++col) {
                    factor_row[col] =
                        dst[(start + lane) * sg_n + start + col];
                }
                #pragma unroll
                for (int k = 0; k < sg_nb; ++k) {
                    float value = factor_row[k];
                    float diagonal_reciprocal = 0.0f;
                    if (lane == k) {
                        #pragma unroll
                        for (int p = 0; p < k; ++p) {
                            const float x = factor_row[p];
                            value = fmaf(-x, x, value);
                        }
                        value = fmaxf(value, 1.0e-20f);
                        if constexpr (SG_N == 2048) {
                            diagonal_reciprocal = sp_rsqrt_nr(value);
                            value *= diagonal_reciprocal;
                        } else {
                            value = sqrtf(value);
                        }
                        factor_row[k] = value;
                    }
                    const float diagonal_value =
                        __shfl_sync(0xffffffffu, value, k);
                    if constexpr (SG_N == 2048) {
                        diagonal_reciprocal = __shfl_sync(
                            0xffffffffu, diagonal_reciprocal, k);
                    }
                    if (lane > k) value = factor_row[k];
                    #pragma unroll
                    for (int p = 0; p < k; ++p) {
                        const float pivot = __shfl_sync(
                            0xffffffffu, factor_row[p], k);
                        if (lane > k) {
                            value = fmaf(-factor_row[p], pivot, value);
                        }
                    }
                    if (lane > k) {
                        if constexpr (SG_N == 2048) {
                            factor_row[k] = value * diagonal_reciprocal;
                        } else {
                            factor_row[k] = value / diagonal_value;
                        }
                    }
                }
                #pragma unroll
                for (int col = 0; col < sg_nb; ++col) {
                    if (lane >= col) {
                        dst[(start + lane) * sg_n + start + col] =
                            factor_row[col];
                    }
                }
            }
        }
        const bool factor_scheduler_reserved = sg_factor_frontier_pipeline
            ? (rank == 0)
            : (rank == 0 && warp == 0);
        if (!SG_FP32_PANEL && end < sg_n &&
            !factor_scheduler_reserved) {
            if constexpr (sg_factor_frontier_pipeline) {
                constexpr int worker_warps =
                    (sg_ctas - 1) * sg_warps;
                const int worker_warp = grid_warp - sg_warps;
                if (phase > 0) {
                    const int active_k = phase * sg_nb;
                    const int row_tiles = (sg_n - end) / 16;
                    for (int tile_row = worker_warp; tile_row < row_tiles;
                         tile_row += worker_warps) {
                        const int row = end + 16 * tile_row;
                        sp_accum_fragment accum[2];
                        #pragma unroll
                        for (int q = 0; q < 2; ++q) {
                            sp_wmma::load_matrix_sync(
                                accum[q],
                                dst + row * sg_n + start + 16 * q,
                                sg_n, sp_wmma::mem_row_major);
                        }
                        #pragma unroll
                        for (int k = 0; k < active_k; k += 16) {
                            sp_left_fragment left;
                            sp_wmma::load_matrix_sync(
                                left, hp + row * sg_stride + k, sg_stride);
                            #pragma unroll
                            for (int element = 0;
                                 element < left.num_elements; ++element) {
                                left.x[element] = __hneg(left.x[element]);
                            }
                            #pragma unroll
                            for (int q = 0; q < 2; ++q) {
                                sp_right_fragment right;
                                sp_wmma::load_matrix_sync(
                                    right,
                                    hp + (start + 16 * q) * sg_stride + k,
                                    sg_stride);
                                sp_wmma::mma_sync(
                                    accum[q], left, right, accum[q]);
                            }
                        }
                        #pragma unroll
                        for (int q = 0; q < 2; ++q) {
                            float* tile = panel_store +
                                (warp * 2 + q) * 16 * 16;
                            sp_wmma::store_matrix_sync(
                                tile, accum[q], 16,
                                sp_wmma::mem_row_major);
                            __syncwarp();
                            for (int index = lane; index < 16 * 16;
                                 index += 32) {
                                const int local_row = index / 16;
                                const int local_col = index % 16;
                                const float value = tile[index];
                                dst[(row + local_row) * sg_n + start +
                                    q * 16 + local_col] = value;
                                hi[(row + local_row) * sg_nb +
                                   q * 16 + local_col] =
                                    __float2half_rn(value);
                            }
                            __syncwarp();
                        }
                    }
                } else {
                    constexpr int workers = worker_warps * 32;
                    const int worker = worker_warp * 32 + lane;
                    for (int index = worker; index < panel_count;
                         index += workers) {
                        const int row = end + index / sg_nb;
                        const int col = index % sg_nb;
                        hi[row * sg_nb + col] = __float2half_rn(
                            dst[row * sg_n + start + col]);
                    }
                }
            } else {
                constexpr int reserved = 32;
                constexpr int workers = sg_ctas * sg_threads - reserved;
                const int worker = grid_thread - reserved;
                for (int index = worker; index < panel_count;
                     index += workers) {
                    const int row = end + index / sg_nb;
                    const int col = index % sg_nb;
                    hi[row * sg_nb + col] =
                        __float2half_rn(dst[row * sg_n + start + col]);
                }
            }
        }
        grid.sync();
        if (end == sg_n) break;

        if constexpr (SG_FP32_PANEL) {
            if (tid < sg_nb) {
                panel_reciprocal[tid] =
                    1.0f / dst[(start + tid) * sg_n + start + tid];
            }
            __syncthreads();
            for (int row = end + grid_thread; row < sg_n;
                 row += sg_ctas * sg_threads) {
                float solved[sg_nb];
                #pragma unroll
                for (int col = 0; col < sg_nb; ++col) {
                    float value = dst[row * sg_n + start + col];
                    #pragma unroll
                    for (int p = 0; p < col; ++p) {
                        value = fmaf(
                            -dst[(start + col) * sg_n + start + p],
                            solved[p], value);
                    }
                    solved[col] = value * panel_reciprocal[col];
                    dst[row * sg_n + start + col] = solved[col];
                    hp[row * sg_stride + phase_offset + col] =
                        __float2half_rn(solved[col]);
                }
            }
        } else {
        if (rank == 0) {
            constexpr int half = sg_nb / 2;
            float* inverse_a = panel_store;
            float* inverse_d = inverse_a + half * half;
            float* middle = inverse_d + half * half;
            if (tid < sg_nb) {
                panel_reciprocal[tid] = 1.0f /
                    dst[(start + tid) * sg_n + start + tid];
            }
            __syncthreads();
            if constexpr (SG_N == 256 || SG_N == 2048) {
                if (tid < 2 * 8 * 8) {
                    const int block16 = tid >> 6;
                    const int local = tid & 63;
                    const int row = local >> 3;
                    const int col = local & 7;
                    float* target = inverse_a + block16 * half * half;
                    target[row * half + 8 + col] = 0.0f;
                }
                if (warp < 4) {
                    const int block16 = warp >> 1;
                    const int block8 = (warp & 1) * 8;
                    const int inverse4_element = lane & 15;
                    const int inverse4_block = lane >> 4;
                    const int inverse4_row = inverse4_element >> 2;
                    const int inverse4_col = inverse4_element & 3;
                    const int inverse4_offset = block8 + 4 * inverse4_block;
                    float* target = inverse_a + block16 * half * half;
                    const int matrix_offset = block16 * half;
                    if (lane < 4 * 4) {
                        const int row = lane >> 2;
                        const int col = lane & 3;
                        target[(block8 + row) * half + block8 + 4 + col] =
                            0.0f;
                    }
                    float inverse4_value = 0.0f;
                    if (inverse4_row == inverse4_col) {
                        inverse4_value = panel_reciprocal[
                            matrix_offset + inverse4_offset + inverse4_row];
                    }
                    const float inverse4_diag = __shfl_sync(
                        0xffffffffu, inverse4_value,
                        4 * inverse4_col + inverse4_col, 16);
                    if (inverse4_row == inverse4_col + 1) {
                        const float product = __fmul_rn(
                            dst[(start + matrix_offset + inverse4_offset +
                                 inverse4_row) * sg_n +
                                start + matrix_offset + inverse4_offset +
                                inverse4_col], inverse4_diag);
                        inverse4_value =
                            (0.0f - product) * panel_reciprocal[
                                matrix_offset + inverse4_offset + inverse4_row];
                    }
                    const int inverse4_next = min(inverse4_col + 1, 3);
                    const float inverse4_d2_0 = __shfl_sync(
                        0xffffffffu, inverse4_value,
                        4 * inverse4_col + inverse4_col, 16);
                    const float inverse4_d2_1 = __shfl_sync(
                        0xffffffffu, inverse4_value,
                        4 * inverse4_next + inverse4_col, 16);
                    if (inverse4_row == inverse4_col + 2) {
                        const float product0 = __fmul_rn(
                            dst[(start + matrix_offset + inverse4_offset +
                                 inverse4_row) * sg_n +
                                start + matrix_offset + inverse4_offset +
                                inverse4_col], inverse4_d2_0);
                        const float product1 = __fmul_rn(
                            dst[(start + matrix_offset + inverse4_offset +
                                 inverse4_row) * sg_n +
                                start + matrix_offset + inverse4_offset +
                                inverse4_col + 1], inverse4_d2_1);
                        const float sum = __fadd_rn(product0, product1);
                        inverse4_value =
                            (0.0f - sum) * panel_reciprocal[
                                matrix_offset + inverse4_offset + inverse4_row];
                    }
                    const float inverse4_d3_0 = __shfl_sync(
                        0xffffffffu, inverse4_value, 0, 16);
                    const float inverse4_d3_1 = __shfl_sync(
                        0xffffffffu, inverse4_value, 4, 16);
                    const float inverse4_d3_2 = __shfl_sync(
                        0xffffffffu, inverse4_value, 8, 16);
                    if (inverse4_row == 3 && inverse4_col == 0) {
                        const float product0 = __fmul_rn(
                            dst[(start + matrix_offset + inverse4_offset + 3) *
                                    sg_n + start + matrix_offset +
                                inverse4_offset], inverse4_d3_0);
                        const float product1 = __fmul_rn(
                            dst[(start + matrix_offset + inverse4_offset + 3) *
                                    sg_n + start + matrix_offset +
                                inverse4_offset + 1], inverse4_d3_1);
                        const float product2 = __fmul_rn(
                            dst[(start + matrix_offset + inverse4_offset + 3) *
                                    sg_n + start + matrix_offset +
                                inverse4_offset + 2], inverse4_d3_2);
                        const float sum = __fadd_rn(
                            __fadd_rn(product0, product2), product1);
                        inverse4_value =
                            (0.0f - sum) * panel_reciprocal[
                                matrix_offset + inverse4_offset + 3];
                    }
                    target[(inverse4_offset + inverse4_row) * half +
                           inverse4_offset + inverse4_col] = inverse4_value;
                    __syncwarp();
                    if (lane < 4 * 4) {
                        const int row = lane >> 2;
                        const int col = lane & 3;
                        float value = 0.0f;
                        #pragma unroll
                        for (int k = 0; k < 4; ++k) {
                            value = fmaf(
                                target[(block8 + 4 + row) * half +
                                       block8 + 4 + k],
                                dst[(start + matrix_offset + block8 + 4 + k) *
                                    sg_n + start + matrix_offset + block8 + col],
                                value);
                        }
                        middle[warp * 16 + row * 4 + col] = value;
                    }
                    __syncwarp();
                    {
                        const int element = lane & 15;
                        const int row = element >> 2;
                        const int col = element & 3;
                        const int k0 = (lane >> 4) * 2;
                        float value = 0.0f;
                        #pragma unroll
                        for (int local_k = 0; local_k < 2; ++local_k) {
                            const int k = k0 + local_k;
                            value = fmaf(
                                middle[warp * 16 + row * 4 + k],
                                target[(block8 + k) * half + block8 + col],
                                value);
                        }
                        value += __shfl_xor_sync(
                            0xffffffffu, value, 16);
                        if (lane < 16) {
                            target[(block8 + 4 + row) * half + block8 + col] =
                                -value;
                        }
                    }
                }
                __syncthreads();
                if (tid < 2 * 8 * 8) {
                    const int block16 = tid >> 6;
                    const int local = tid & 63;
                    const int row = local >> 3;
                    const int col = local & 7;
                    float* target = inverse_a + block16 * half * half;
                    const int matrix_offset = block16 * half;
                    float value = 0.0f;
                    #pragma unroll
                    for (int k = 0; k < 8; ++k) {
                        value = fmaf(
                            target[(8 + row) * half + 8 + k],
                            dst[(start + matrix_offset + 8 + k) * sg_n +
                                start + matrix_offset + col], value);
                    }
                    middle[block16 * 64 + row * 8 + col] = value;
                }
                __syncthreads();
                if (tid < 2 * 8 * 8) {
                    const int block16 = tid >> 6;
                    const int local = tid & 63;
                    const int row = local >> 3;
                    const int col = local & 7;
                    float* target = inverse_a + block16 * half * half;
                    float value = 0.0f;
                    #pragma unroll
                    for (int k = 0; k < 8; ++k) {
                        value = fmaf(
                            middle[block16 * 64 + row * 8 + k],
                            target[k * half + col], value);
                    }
                    target[(8 + row) * half + col] = -value;
                }
            } else {
                const int inverse_lane = lane & 15;
                const int inverse_offset = (lane >> 4) * half;
                float* inverse_block = inverse_a + inverse_offset * half;
                const int inverse_col = warp;
                const int inverse_index = inverse_col + inverse_lane;
                float inverse_value = 0.0f;
                if (inverse_lane < inverse_col) {
                    inverse_block[inverse_lane * half + inverse_col] = 0.0f;
                }
                #pragma unroll
                for (int inverse_row = inverse_col;
                     inverse_row < half; ++inverse_row) {
                    float product = 0.0f;
                    if (inverse_index < inverse_row) {
                        product = dst[
                            (start + inverse_offset + inverse_row) * sg_n +
                            start + inverse_offset + inverse_index] *
                            inverse_value;
                    }
                    #pragma unroll
                    for (int offset = 8; offset; offset >>= 1) {
                        product += __shfl_down_sync(
                            0xffffffffu, product, offset, 16);
                    }
                    const float sum =
                        __shfl_sync(0xffffffffu, product, 0, 16);
                    if (inverse_index == inverse_row) {
                        const float identity =
                            (inverse_row == inverse_col) ? 1.0f : 0.0f;
                        inverse_value = (identity - sum) *
                            panel_reciprocal[inverse_offset + inverse_row];
                        inverse_block[inverse_row * half + inverse_col] =
                            inverse_value;
                    }
                }
            }
            __syncthreads();
            if constexpr (SG_N == 256 || SG_N == 2048) {
                if (warp < half) {
                    const int row = warp;
                    const int col = lane & (half - 1);
                    const int k0 = (lane >> 4) * 8;
                    float value = 0.0f;
                    #pragma unroll
                    for (int local_k = 0; local_k < 8; ++local_k) {
                        const int k = k0 + local_k;
                        if (k <= row) {
                            value = fmaf(
                                inverse_d[row * half + k],
                                dst[(start + half + k) * sg_n + start + col],
                                value);
                        }
                    }
                    value += __shfl_xor_sync(0xffffffffu, value, half);
                    if (lane < half) {
                        middle[row * half + col] = value;
                    }
                }
            } else if (tid < half * half) {
                const int row = tid / half;
                const int col = tid - row * half;
                float value = 0.0f;
                #pragma unroll
                for (int k = 0; k < half; ++k) {
                    if (k <= row) {
                        value = fmaf(
                            inverse_d[row * half + k],
                            dst[(start + half + k) * sg_n + start + col],
                            value);
                    }
                }
                middle[row * half + col] = value;
            }
            __syncthreads();
            if (tid < half * half) {
                const int row = tid / half;
                const int col = tid - row * half;
                float lower_left = 0.0f;
                #pragma unroll
                for (int k = 0; k < half; ++k) {
                    if (k >= col) {
                        lower_left = fmaf(
                            middle[row * half + k],
                            inverse_a[k * half + col], lower_left);
                    }
                }
                ih[row * sg_nb + col] =
                    __float2half_rn(inverse_a[row * half + col]);
                ih[row * sg_nb + half + col] = __float2half_rn(0.0f);
                ih[(half + row) * sg_nb + col] =
                    __float2half_rn(-lower_left);
                ih[(half + row) * sg_nb + half + col] =
                    __float2half_rn(inverse_d[row * half + col]);
            }
            __syncthreads();
        }
        grid.sync();

        const int panel_row_tiles = (sg_n - end) / 16;
        bool split_panel_outputs = false;
        if constexpr (sg_factor_frontier_pipeline) {
            split_panel_outputs = panel_row_tiles <= 64;
        }
        if (split_panel_outputs) {
        const int panel_jobs = panel_row_tiles * 2;
        for (int job = grid_warp; job < panel_jobs;
             job += sg_ctas * sg_warps) {
            const int tile_row = job >> 1;
            const int q = job & 1;
            const int row = end + 16 * tile_row;
            sp_accum_fragment accum;
            sp_wmma::fill_fragment(accum, 0.0f);
            #pragma unroll
            for (int k = 0; k < sg_nb; k += 16) {
                sp_left_fragment left;
                sp_right_fragment right;
                sp_wmma::load_matrix_sync(
                    left, hi + row * sg_nb + k, sg_nb);
                sp_wmma::load_matrix_sync(
                    right, ih + q * 16 * sg_nb + k, sg_nb);
                sp_wmma::mma_sync(accum, left, right, accum);
            }
            float* tile = panel_store + (warp * 2 + q) * 16 * 16;
            sp_wmma::store_matrix_sync(
                tile, accum, 16, sp_wmma::mem_row_major);
            __syncwarp();
            for (int index = lane; index < 16 * 16; index += 32) {
                const int local_row = index / 16;
                const int local_col = index % 16;
                const float value = tile[index];
                dst[(row + local_row) * sg_n + start + q * 16 +
                    local_col] = value;
                hp[(row + local_row) * sg_stride + phase_offset +
                   q * 16 + local_col] = __float2half_rn(value);
            }
            __syncwarp();
        }
        } else {
        for (int tile_row = grid_warp; tile_row < panel_row_tiles;
             tile_row += sg_ctas * sg_warps) {
            const int row = end + 16 * tile_row;
            sp_accum_fragment accum[2];
            sp_wmma::fill_fragment(accum[0], 0.0f);
            sp_wmma::fill_fragment(accum[1], 0.0f);
            #pragma unroll
            for (int k = 0; k < sg_nb; k += 16) {
                sp_left_fragment left;
                sp_wmma::load_matrix_sync(left, hi + row * sg_nb + k, sg_nb);
                #pragma unroll
                for (int q = 0; q < 2; ++q) {
                    sp_right_fragment right;
                    sp_wmma::load_matrix_sync(
                        right, ih + q * 16 * sg_nb + k, sg_nb);
                    sp_wmma::mma_sync(accum[q], left, right, accum[q]);
                }
            }
            #pragma unroll
            for (int q = 0; q < 2; ++q) {
                float* tile = panel_store + (warp * 2 + q) * 16 * 16;
                sp_wmma::store_matrix_sync(
                    tile, accum[q], 16, sp_wmma::mem_row_major);
                __syncwarp();
                for (int index = lane; index < 16 * 16; index += 32) {
                    const int local_row = index / 16;
                    const int local_col = index % 16;
                    const float value = tile[index];
                    dst[(row + local_row) * sg_n + start + q * 16 +
                        local_col] = value;
                    hp[(row + local_row) * sg_stride + phase_offset +
                       q * 16 + local_col] = __float2half_rn(value);
                }
                __syncwarp();
            }
        }
        }
        }
        grid.sync();

        if (phase < (sg_rankk / sg_nb) - 1) {
            const int active_k = (phase + 1) * sg_nb;
            if constexpr (sg_factor_frontier_pipeline) {
                if (rank == 0) {
                    if (warp < 3) {
                        const int tile_row = warp == 0 ? 0 : 1;
                        const int q = warp == 2 ? 1 : 0;
                        const int row = end + 16 * tile_row;
                        sp_accum_fragment accum;
                        sp_wmma::load_matrix_sync(
                            accum, dst + row * sg_n + end + 16 * q,
                            sg_n, sp_wmma::mem_row_major);
                        #pragma unroll
                        for (int k = 0; k < active_k; k += 16) {
                            sp_left_fragment left;
                            sp_wmma::load_matrix_sync(
                                left, hp + row * sg_stride + k, sg_stride);
                            #pragma unroll
                            for (int element = 0;
                                 element < left.num_elements; ++element) {
                                left.x[element] = __hneg(left.x[element]);
                            }
                            sp_right_fragment right;
                            sp_wmma::load_matrix_sync(
                                right,
                                hp + (end + 16 * q) * sg_stride + k,
                                sg_stride);
                            sp_wmma::mma_sync(
                                accum, left, right, accum);
                        }
                        sp_wmma::store_matrix_sync(
                            dst + row * sg_n + end + 16 * q,
                            accum, sg_n, sp_wmma::mem_row_major);
                    }
                    __syncthreads();
                }
                continue;
            } else if constexpr (SG_FP32_UPDATE) {
                const int group_start = start - phase * sg_nb;
                const int frontier_elements = (sg_n - end) * sg_nb;
                for (int index = grid_thread; index < frontier_elements;
                     index += sg_ctas * sg_threads) {
                    const int row = end + index / sg_nb;
                    const int col = end + index % sg_nb;
                    if (col <= row) {
                        float value = dst[row * sg_n + col];
                        #pragma unroll 4
                        for (int k = 0; k < active_k; ++k) {
                            value = fmaf(
                                -dst[row * sg_n + group_start + k],
                                dst[col * sg_n + group_start + k], value);
                        }
                        dst[row * sg_n + col] = value;
                    }
                }
                grid.sync();
                continue;
            }
            const int row_tiles = (sg_n - end) / 16;
            for (int tile_row = grid_warp; tile_row < row_tiles;
                 tile_row += sg_ctas * sg_warps) {
                const int row = end + 16 * tile_row;
                sp_accum_fragment accum[2];
                #pragma unroll
                for (int q = 0; q < 2; ++q) {
                    if (q <= tile_row) {
                        sp_wmma::load_matrix_sync(
                            accum[q], dst + row * sg_n + end + 16 * q,
                            sg_n, sp_wmma::mem_row_major);
                    }
                }
                #pragma unroll
                for (int k = 0; k < active_k; k += 16) {
                    sp_left_fragment left;
                    sp_wmma::load_matrix_sync(
                        left, hp + row * sg_stride + k, sg_stride);
                    #pragma unroll
                    for (int element = 0; element < left.num_elements;
                         ++element) {
                        left.x[element] = __hneg(left.x[element]);
                    }
                    #pragma unroll
                    for (int q = 0; q < 2; ++q) {
                        if (q <= tile_row) {
                            sp_right_fragment right;
                            sp_wmma::load_matrix_sync(
                                right,
                                hp + (end + 16 * q) * sg_stride + k,
                                sg_stride);
                            sp_wmma::mma_sync(
                                accum[q], left, right, accum[q]);
                        }
                    }
                }
                #pragma unroll
                for (int q = 0; q < 2; ++q) {
                    if (q <= tile_row) {
                        sp_wmma::store_matrix_sync(
                            dst + row * sg_n + end + 16 * q,
                            accum[q], sg_n, sp_wmma::mem_row_major);
                    }
                }
            }
            grid.sync();
            continue;
        }

        if constexpr (SG_EXTERNAL_UPDATE) {
            continue;
        }

        const int tile_count = (sg_n - end) / 16;
        int job = 0;
        for (int tile_row = 0; tile_row < tile_count; ++tile_row) {
            const int groups = tile_row / 5 + 1;
            for (int group = 0; group < groups; ++group, ++job) {
                if (job % (sg_ctas * sg_warps) != grid_warp) continue;
                const int row = end + 16 * tile_row;
                const int first_col = 5 * group;
                sp_accum_fragment accum[5];
                #pragma unroll
                for (int q = 0; q < 5; ++q) {
                    if (first_col + q <= tile_row) {
                        const int col = end + 16 * (first_col + q);
                        sp_wmma::load_matrix_sync(
                            accum[q], dst + row * sg_n + col, sg_n,
                            sp_wmma::mem_row_major);
                    }
                }
                #pragma unroll
                for (int k = 0; k < sg_rankk; k += 16) {
                    sp_left_fragment left;
                    sp_wmma::load_matrix_sync(
                        left, hp + row * sg_stride + k, sg_stride);
                    #pragma unroll
                    for (int element = 0; element < left.num_elements;
                         ++element) {
                        left.x[element] = __hneg(left.x[element]);
                    }
                    #pragma unroll
                    for (int q = 0; q < 5; ++q) {
                        if (first_col + q <= tile_row) {
                            const int col = end + 16 * (first_col + q);
                            sp_right_fragment right;
                            sp_wmma::load_matrix_sync(
                                right, hp + col * sg_stride + k, sg_stride);
                            sp_wmma::mma_sync(
                                accum[q], left, right, accum[q]);
                        }
                    }
                }
                #pragma unroll
                for (int q = 0; q < 5; ++q) {
                    if (first_col + q <= tile_row) {
                        const int col = end + 16 * (first_col + q);
                        sp_wmma::store_matrix_sync(
                            dst + row * sg_n + col, accum[q], sg_n,
                            sp_wmma::mem_row_major);
                    }
                }
            }
        }
        grid.sync();
    }

    if constexpr (!SG_EXTERNAL_UPDATE) {
        constexpr int diagonal_tile = 16;
        constexpr int diagonal_elements =
            (sg_n / diagonal_tile) * diagonal_tile * diagonal_tile;
        for (int index = grid_thread; index < diagonal_elements;
             index += sg_ctas * sg_threads) {
            const int tile = index / (diagonal_tile * diagonal_tile);
            const int local = index - tile * diagonal_tile * diagonal_tile;
            const int row = local / diagonal_tile;
            const int col = local - row * diagonal_tile;
            if (col > row) {
                const int base = tile * diagonal_tile;
                dst[(base + row) * sg_n + base + col] = 0.0f;
            }
        }
    }
}

constexpr int ss_n = 128;
constexpr int ss_nb = 32;
constexpr int ss_stride = 160;
constexpr int ss_threads = 256;
constexpr int ss_warps = ss_threads / 32;
constexpr size_t ss_matrix_elements = ss_n * ss_n;
constexpr size_t ss_half_elements = ss_n * ss_stride;
constexpr size_t ss_shared_bytes =
    ss_matrix_elements * sizeof(float) +
    ss_half_elements * sizeof(__half) + ss_nb * sizeof(float);

__global__ void __launch_bounds__(ss_threads, 1) ss_potrf128_kernel(
    const float* __restrict__ input,
    float* __restrict__ output) {
    extern __shared__ unsigned char shared_bytes[];
    float* matrix = reinterpret_cast<float*>(shared_bytes);
    __half* panel = reinterpret_cast<__half*>(matrix + ss_matrix_elements);
    float* reciprocal = reinterpret_cast<float*>(panel + ss_half_elements);
    const int tid = static_cast<int>(threadIdx.x);
    const int lane = tid & 31;
    const int warp = tid >> 5;
    const int batch_index = static_cast<int>(blockIdx.x);
    const float* src = input + static_cast<size_t>(batch_index) *
        ss_matrix_elements;
    float* dst = output + static_cast<size_t>(batch_index) *
        ss_matrix_elements;
    float* inverse = reinterpret_cast<float*>(panel);
    float* inverse_a = inverse + ss_nb * ss_nb;
    float* inverse_d = inverse_a + 16 * 16;
    float* middle = inverse_d + 16 * 16;

    const float4* src4 = reinterpret_cast<const float4*>(src);
    for (int index = tid; index < ss_matrix_elements / 4;
         index += ss_threads) {
        constexpr int vectors_per_row = ss_n / 4;
        const int row = index / vectors_per_row;
        const int vector_col = index - row * vectors_per_row;
        const int col = 4 * vector_col;
        float4 value = make_float4(0.0f, 0.0f, 0.0f, 0.0f);
        if (col <= row) {
            value = src4[index];
            if (col + 1 > row) value.y = 0.0f;
            if (col + 2 > row) value.z = 0.0f;
            if (col + 3 > row) value.w = 0.0f;
        }
        *reinterpret_cast<float4*>(matrix + 4 * index) = value;
    }
    __syncthreads();

    for (int start = 0; start < ss_n; start += ss_nb) {
        const int end = start + ss_nb;
        const int phase = start / ss_nb;
        const int phase_offset = phase * ss_nb;
        if (warp == 0) {
            constexpr int factor_tile = 16;
            __half* factor_high = panel;
            __half* factor_low = factor_high + factor_tile * factor_tile;
            float* factor_schur = reinterpret_cast<float*>(
                factor_low + factor_tile * factor_tile);
            #pragma unroll
            for (int base = 0; base < ss_nb; base += factor_tile) {
                if (base == factor_tile) {
                    for (int index = lane;
                         index < factor_tile * factor_tile; index += 32) {
                        const int row = factor_tile + index / factor_tile;
                        const int col = index % factor_tile;
                        const float value =
                            matrix[(start + row) * ss_n + start + col];
                        const __half high = __float2half_rn(value);
                        factor_high[index] = high;
                        factor_low[index] = __float2half_rn(
                            value - __half2float(high));
                    }
                    __syncwarp();
                    sp_accum_fragment schur;
                    sp_wmma::load_matrix_sync(
                        schur,
                        matrix + (start + factor_tile) * ss_n +
                            start + factor_tile,
                        ss_n, sp_wmma::mem_row_major);
                    sp_left_fragment left;
                    sp_right_fragment right;
                    sp_wmma::load_matrix_sync(left, factor_high, factor_tile);
                    #pragma unroll
                    for (int element = 0; element < left.num_elements;
                         ++element) {
                        left.x[element] = __hneg(left.x[element]);
                    }
                    sp_wmma::load_matrix_sync(right, factor_high, factor_tile);
                    sp_wmma::mma_sync(schur, left, right, schur);
                    sp_wmma::load_matrix_sync(right, factor_low, factor_tile);
                    sp_wmma::mma_sync(schur, left, right, schur);
                    sp_wmma::load_matrix_sync(left, factor_low, factor_tile);
                    #pragma unroll
                    for (int element = 0; element < left.num_elements;
                         ++element) {
                        left.x[element] = __hneg(left.x[element]);
                    }
                    sp_wmma::load_matrix_sync(right, factor_high, factor_tile);
                    sp_wmma::mma_sync(schur, left, right, schur);
                    sp_wmma::store_matrix_sync(
                        factor_schur, schur, factor_tile,
                        sp_wmma::mem_row_major);
                    __syncwarp();
                }

                float factor_chunk[factor_tile];
                #pragma unroll
                for (int q = 0; q < factor_tile; ++q) {
                    factor_chunk[q] = base == factor_tile
                        ? ((lane >= factor_tile)
                            ? factor_schur[
                                (lane - factor_tile) * factor_tile + q]
                            : 0.0f)
                        : matrix[(start + lane) * ss_n + start + q];
                }
                #pragma unroll
                for (int q = 0; q < factor_tile; ++q) {
                    const int k = base + q;
                    float value = factor_chunk[q];
                    #pragma unroll
                    for (int p = 0; p < q; ++p) {
                        const float pivot = __shfl_sync(
                            0xffffffffu, factor_chunk[p], k);
                        if (lane >= k) {
                            value = fmaf(-factor_chunk[p], pivot, value);
                        }
                    }
                    float inverse_diagonal = 0.0f;
                    if (lane == k) {
                        value = fmaxf(value, 1.0e-20f);
                        inverse_diagonal = sp_rsqrt_nr(value);
                    }
                    inverse_diagonal = __shfl_sync(
                        0xffffffffu, inverse_diagonal, k);
                    if (lane >= k) {
                        factor_chunk[q] = value * inverse_diagonal;
                    }
                }
                #pragma unroll
                for (int q = 0; q < factor_tile; ++q) {
                    const int col = base + q;
                    if (lane >= col) {
                        matrix[(start + lane) * ss_n + start + col] =
                            factor_chunk[q];
                    }
                }
                __syncwarp();
                if (base == 0 && end < ss_n) {
                    if (lane < factor_tile) {
                        reciprocal[lane] = 1.0f / matrix[
                            (start + lane) * ss_n + start + lane];
                    }
                    __syncwarp();
                    asm volatile("bar.arrive 1, 256;" ::: "memory");
                }
            }
        }
        if (end < ss_n && warp != 0) {
            constexpr int workers = ss_threads - 32;
            const int worker = tid - 32;
            const int panel_count = (ss_n - end) * ss_nb;
            for (int index = worker; index < panel_count; index += workers) {
                const int row = end + index / ss_nb;
                const int col = index % ss_nb;
                const float value =
                    matrix[row * ss_n + start + col];
                const __half high = __float2half_rn(value);
                panel[row * ss_stride + phase_offset + col] = high;
            }
            asm volatile("bar.sync 1, 256;" ::: "memory");
            const int inverse_lane_early = lane & 15;
            const int inverse_group_early = lane >> 4;
            const unsigned inverse_mask_early = inverse_group_early == 0
                ? 0x0000ffffu : 0xffff0000u;
            const int inverse_worker_early =
                2 * (warp - 1) + inverse_group_early;
            #pragma unroll
            for (int inverse_col_early = inverse_worker_early;
                 inverse_col_early < 16; inverse_col_early += 14) {
                const int inverse_index_early =
                    inverse_col_early + inverse_lane_early;
                float inverse_value_early = 0.0f;
                if (inverse_lane_early < inverse_col_early) {
                    inverse_a[inverse_lane_early * 16 +
                              inverse_col_early] = 0.0f;
                }
                #pragma unroll
                for (int inverse_row_early = inverse_col_early;
                     inverse_row_early < 16; ++inverse_row_early) {
                    float product_early = 0.0f;
                    if (inverse_index_early < inverse_row_early) {
                        product_early = matrix[
                            (start + inverse_row_early) * ss_n +
                            start + inverse_index_early] *
                            inverse_value_early;
                    }
                    #pragma unroll
                    for (int offset = 8; offset; offset >>= 1) {
                        product_early += __shfl_down_sync(
                            inverse_mask_early, product_early, offset, 16);
                    }
                    const float sum_early = __shfl_sync(
                        inverse_mask_early, product_early, 0, 16);
                    if (inverse_index_early == inverse_row_early) {
                        const float identity =
                            inverse_row_early == inverse_col_early
                                ? 1.0f : 0.0f;
                        inverse_value_early = (identity - sum_early) *
                            reciprocal[inverse_row_early];
                        inverse_a[inverse_row_early * 16 +
                                  inverse_col_early] = inverse_value_early;
                    }
                }
            }
        }
        __syncthreads();
        if (end == ss_n) break;
        if (tid >= 16 && tid < ss_nb) {
            reciprocal[tid] = 1.0f /
                matrix[(start + tid) * ss_n + start + tid];
        }
        __syncthreads();

        if (tid < 8 * 8) {
            const int row = tid >> 3;
            const int col = tid & 7;
            inverse_d[row * 16 + 8 + col] = 0.0f;
        }
        if (warp < 2) {
            const int block8 = warp * 8;
            const int inverse4_lane = lane & 3;
            const int inverse4_group = lane >> 2;
            const int inverse4_block = inverse4_group >> 2;
            const int inverse4_col = inverse4_group & 3;
            const int inverse4_offset = block8 + 4 * inverse4_block;
            const int inverse4_index = inverse4_col + inverse4_lane;
            if (lane < 4 * 4) {
                const int row = lane >> 2;
                const int col = lane & 3;
                inverse_d[(block8 + row) * 16 + block8 + 4 + col] = 0.0f;
            }
            float inverse4_value = 0.0f;
            if (inverse4_lane < inverse4_col) {
                inverse_d[(inverse4_offset + inverse4_lane) * 16 +
                          inverse4_offset + inverse4_col] = 0.0f;
            }
            #pragma unroll
            for (int inverse4_row = 0; inverse4_row < 4; ++inverse4_row) {
                float inverse4_product = 0.0f;
                if (inverse4_row >= inverse4_col &&
                    inverse4_index < inverse4_row) {
                    inverse4_product = matrix[
                        (start + 16 + inverse4_offset + inverse4_row) * ss_n +
                        start + 16 + inverse4_offset + inverse4_index] *
                        inverse4_value;
                }
                #pragma unroll
                for (int offset = 2; offset; offset >>= 1) {
                    inverse4_product += __shfl_down_sync(
                        0xffffffffu, inverse4_product, offset, 4);
                }
                const float inverse4_sum = __shfl_sync(
                    0xffffffffu, inverse4_product, 0, 4);
                if (inverse4_row >= inverse4_col &&
                    inverse4_index == inverse4_row) {
                    const float identity =
                        inverse4_row == inverse4_col ? 1.0f : 0.0f;
                    inverse4_value = (identity - inverse4_sum) * reciprocal[
                        16 + inverse4_offset + inverse4_row];
                    inverse_d[(inverse4_offset + inverse4_row) * 16 +
                              inverse4_offset + inverse4_col] = inverse4_value;
                }
            }
            __syncwarp();
            if (lane < 4 * 4) {
                const int row = lane >> 2;
                const int col = lane & 3;
                float value = 0.0f;
                #pragma unroll
                for (int k = 0; k < 4; ++k) {
                    value = fmaf(
                        inverse_d[(block8 + 4 + row) * 16 + block8 + 4 + k],
                        matrix[(start + 16 + block8 + 4 + k) * ss_n +
                               start + 16 + block8 + col],
                        value);
                }
                middle[warp * 16 + row * 4 + col] = value;
            }
            __syncwarp();
            if (lane < 4 * 4) {
                const int row = lane >> 2;
                const int col = lane & 3;
                float value = 0.0f;
                #pragma unroll
                for (int k = 0; k < 4; ++k) {
                    value = fmaf(
                        middle[warp * 16 + row * 4 + k],
                        inverse_d[(block8 + k) * 16 + block8 + col], value);
                }
                inverse_d[(block8 + 4 + row) * 16 + block8 + col] = -value;
            }
        }
        __syncthreads();

        if (tid < 8 * 8) {
            const int row = tid >> 3;
            const int col = tid & 7;
            float value = 0.0f;
            #pragma unroll
            for (int k = 0; k < 8; ++k) {
                value = fmaf(
                    inverse_d[(8 + row) * 16 + 8 + k],
                    matrix[(start + 24 + k) * ss_n + start + 16 + col],
                    value);
            }
            middle[row * 8 + col] = value;
        }
        __syncthreads();

        if (tid < 8 * 8) {
            const int row = tid >> 3;
            const int col = tid & 7;
            float value = 0.0f;
            #pragma unroll
            for (int k = 0; k < 8; ++k) {
                value = fmaf(
                    middle[row * 8 + k], inverse_d[k * 16 + col], value);
            }
            inverse_d[(8 + row) * 16 + col] = -value;
        }
        __syncthreads();

        if (tid < 16 * 16) {
            const int row = tid / 16;
            const int col = tid - row * 16;
            float value = 0.0f;
            #pragma unroll
            for (int k = 0; k < 16; ++k) {
                if (k <= row) {
                    value = fmaf(
                        inverse_d[row * 16 + k],
                        matrix[(start + 16 + k) * ss_n + start + col],
                        value);
                }
            }
            middle[row * 16 + col] = value;
        }
        __syncthreads();

        if (tid < 16 * 16) {
            const int row = tid / 16;
            const int col = tid - row * 16;
            float lower_left = 0.0f;
            #pragma unroll
            for (int k = 0; k < 16; ++k) {
                if (k >= col) {
                    lower_left = fmaf(
                        middle[row * 16 + k],
                        inverse_a[k * 16 + col], lower_left);
                }
            }
            inverse[row * ss_nb + col] = inverse_a[row * 16 + col];
            inverse[row * ss_nb + 16 + col] = 0.0f;
            inverse[(16 + row) * ss_nb + col] = -lower_left;
            inverse[(16 + row) * ss_nb + 16 + col] =
                inverse_d[row * 16 + col];
        }
        __syncthreads();

        __half* inverse_hi = panel + 2 * ss_nb * ss_nb;
        __half* inverse_lo = inverse_hi + ss_nb * ss_nb;
        for (int index = tid; index < ss_nb * ss_nb;
             index += ss_threads) {
            const float value = inverse[index];
            const __half high = __float2half_rn(value);
            inverse_hi[index] = high;
            inverse_lo[index] =
                __float2half_rn(value - __half2float(high));
        }
        __syncthreads();

        const int panel_row_tiles = (ss_n - end) / 16;
        for (int tile_row = warp; tile_row < panel_row_tiles;
             tile_row += ss_warps) {
            const int row = end + 16 * tile_row;
            sp_accum_fragment accum[2];
            sp_wmma::fill_fragment(accum[0], 0.0f);
            sp_wmma::fill_fragment(accum[1], 0.0f);
            #pragma unroll
            for (int k = 0; k < ss_nb; k += 16) {
                sp_left_fragment left_hi;
                sp_wmma::load_matrix_sync(
                    left_hi,
                    panel + row * ss_stride + phase_offset + k,
                    ss_stride);
                #pragma unroll
                for (int q = 0; q < 2; ++q) {
                    sp_right_fragment right_hi;
                    sp_right_fragment right_lo;
                    sp_wmma::load_matrix_sync(
                        right_hi,
                        inverse_hi + q * 16 * ss_nb + k, ss_nb);
                    sp_wmma::load_matrix_sync(
                        right_lo,
                        inverse_lo + q * 16 * ss_nb + k, ss_nb);
                    sp_wmma::mma_sync(
                        accum[q], left_hi, right_hi, accum[q]);
                    sp_wmma::mma_sync(
                        accum[q], left_hi, right_lo, accum[q]);
                }
            }
            #pragma unroll
            for (int q = 0; q < 2; ++q) {
                sp_wmma::store_matrix_sync(
                    matrix + row * ss_n + start + 16 * q,
                    accum[q], ss_n, sp_wmma::mem_row_major);
            }
        }
        __syncthreads();

        const int solved_elements = (ss_n - end) * ss_nb;
        for (int index = tid; index < solved_elements;
             index += ss_threads) {
            const int row = end + index / ss_nb;
            const int col = index - (row - end) * ss_nb;
            panel[row * ss_stride + phase_offset + col] =
                __float2half_rn(matrix[row * ss_n + start + col]);
        }
        __syncthreads();

        const int active_k = (phase + 1) * ss_nb;
        const int row_tiles = (ss_n - end) / 16;
        for (int tile_row = warp; tile_row < row_tiles;
             tile_row += ss_warps) {
            const int row = end + 16 * tile_row;
            sp_accum_fragment accum[2];
            #pragma unroll
            for (int q = 0; q < 2; ++q) {
                if (q <= tile_row) {
                    sp_wmma::load_matrix_sync(
                        accum[q], matrix + row * ss_n + end + 16 * q,
                        ss_n, sp_wmma::mem_row_major);
                }
            }
            #pragma unroll
            for (int k = 0; k < active_k; k += 16) {
                sp_left_fragment left;
                sp_wmma::load_matrix_sync(
                    left, panel + row * ss_stride + k, ss_stride);
                #pragma unroll
                for (int element = 0; element < left.num_elements;
                     ++element) {
                    left.x[element] = __hneg(left.x[element]);
                }
                #pragma unroll
                for (int q = 0; q < 2; ++q) {
                    if (q <= tile_row) {
                        sp_right_fragment right;
                        sp_wmma::load_matrix_sync(
                            right,
                            panel + (end + 16 * q) * ss_stride + k,
                            ss_stride);
                        sp_wmma::mma_sync(
                            accum[q], left, right, accum[q]);
                    }
                }
            }
            #pragma unroll
            for (int q = 0; q < 2; ++q) {
                if (q <= tile_row) {
                    sp_wmma::store_matrix_sync(
                        matrix + row * ss_n + end + 16 * q,
                        accum[q], ss_n, sp_wmma::mem_row_major);
                }
            }
        }
        __syncthreads();
    }

    float4* dst4 = reinterpret_cast<float4*>(dst);
    for (int index = tid; index < ss_matrix_elements / 4;
         index += ss_threads) {
        constexpr int vectors_per_row = ss_n / 4;
        const int row = index / vectors_per_row;
        const int col = 4 * (index - row * vectors_per_row);
        float4 value = *reinterpret_cast<const float4*>(matrix + 4 * index);
        if (col > row) {
            value = make_float4(0.0f, 0.0f, 0.0f, 0.0f);
        } else {
            if (col + 1 > row) value.y = 0.0f;
            if (col + 2 > row) value.z = 0.0f;
            if (col + 3 > row) value.w = 0.0f;
        }
        dst4[index] = value;
    }
}

}  // namespace

torch::Tensor cluster_potrf1024(torch::Tensor input) {
    TORCH_CHECK(input.is_cuda() && input.scalar_type() == torch::kFloat32,
                "input must be CUDA FP32");
    TORCH_CHECK(input.is_contiguous() && input.dim() == 3 &&
                input.size(1) == input.size(2),
                "specialized potrf requires contiguous square batches");
    const int batch = static_cast<int>(input.size(0));
    const int n = static_cast<int>(input.size(1));
    const bool route1024 = batch == 60 && n == 1024;
    const bool route512 = batch == 640 && n == 512;
    TORCH_CHECK(route1024 || route512,
                "specialized potrf requires batch60 n1024 or batch640 n512");
    const int ctas = route1024 ? 2 : 1;
    constexpr int threads = 512;
    const int solved_width = route1024 ? 160 : 224;
    c10::cuda::CUDAGuard guard(input.device());
    auto output = torch::empty_like(input);
    auto panel = torch::empty(
        {input.size(0), n, solved_width},
        input.options().dtype(torch::kFloat16));
    auto panel_input = torch::empty(
        {input.size(0), n, sp_nb},
        input.options().dtype(torch::kFloat16));
    auto inverse = torch::empty(
        {input.size(0), sp_nb, sp_nb},
        input.options().dtype(torch::kFloat16));
    cudaLaunchConfig_t config = {};
    config.gridDim = dim3(static_cast<unsigned>(batch * ctas));
    config.blockDim = dim3(threads);
    config.PC_CAT_(str, eam) = current_q();
    cudaLaunchAttribute attribute = {};
    attribute.id = cudaLaunchAttributeClusterDimension;
    attribute.val.clusterDim.x = ctas;
    attribute.val.clusterDim.y = 1;
    attribute.val.clusterDim.z = 1;
    config.attrs = &attribute;
    config.numAttrs = 1;
    cudaError_t error;
    if (route1024) {
        error = cudaLaunchKernelEx(
            &config, sp_cluster_potrf1024<1024, 2, 512, 160, 160, 5>,
            input.data_ptr<float>(), output.data_ptr<float>(),
            reinterpret_cast<__half*>(panel_input.data_ptr<at::Half>()),
            reinterpret_cast<__half*>(panel.data_ptr<at::Half>()),
            reinterpret_cast<__half*>(inverse.data_ptr<at::Half>()), 0);
    } else {
        error = cudaLaunchKernelEx(
            &config, sp_cluster_potrf1024<512, 1, 512, 192, 224, 4>,
            input.data_ptr<float>(), output.data_ptr<float>(),
            reinterpret_cast<__half*>(panel_input.data_ptr<at::Half>()),
            reinterpret_cast<__half*>(panel.data_ptr<at::Half>()),
            reinterpret_cast<__half*>(inverse.data_ptr<at::Half>()), 0);
    }
    TORCH_CHECK(error == cudaSuccess, "cluster_potrf1024 launch failed: ",
                cudaGetErrorString(error));
    return output;
}

torch::Tensor cluster_potrf512_gemm(torch::Tensor input) {
    constexpr int n = 512;
    constexpr int rankk = 192;
    constexpr int stride = 224;
    constexpr int ctas = 1;
    constexpr int threads = 384;
    TORCH_CHECK(input.is_cuda() && input.scalar_type() == torch::kFloat32 &&
                input.is_contiguous() && input.dim() == 3 &&
                input.size(1) == n && input.size(2) == n,
                "cluster_potrf512_gemm requires contiguous n512 input");
    c10::cuda::CUDAGuard guard(input.device());
    const int batch = static_cast<int>(input.size(0));
    TORCH_CHECK(batch == 4 || batch == 640,
                "cluster_potrf512_gemm supports batch4 or batch640");
    auto output = torch::empty_like(input);
    auto panel = torch::empty(
        {batch, n, stride}, input.options().dtype(torch::kFloat16));
    auto panel_input = torch::empty(
        {batch, n, sp_nb}, input.options().dtype(torch::kFloat16));
    auto inverse = torch::empty(
        {batch, sp_nb, sp_nb}, input.options().dtype(torch::kFloat16));
    if (sg_blas == nullptr) {
        TORCH_CHECK(cublasCreate(&sg_blas) == CUBLAS_STATUS_SUCCESS,
                    "cluster_potrf512_gemm handle creation failed");
        TORCH_CHECK(cublasSetMathMode(sg_blas, CUBLAS_TENSOR_OP_MATH) ==
                        CUBLAS_STATUS_SUCCESS,
                    "cluster_potrf512_gemm math mode failed");
    }
    TORCH_CHECK(PC_CAT_(cublasSetStr, eam)(sg_blas, current_q()) ==
                    CUBLAS_STATUS_SUCCESS,
                "cluster_potrf512_gemm queue binding failed");

    cudaLaunchConfig_t config = {};
    config.gridDim = dim3(static_cast<unsigned>(batch * ctas));
    config.blockDim = dim3(threads);
    config.PC_CAT_(str, eam) = current_q();
    cudaLaunchAttribute attribute = {};
    attribute.id = cudaLaunchAttributeClusterDimension;
    attribute.val.clusterDim.x = ctas;
    attribute.val.clusterDim.y = 1;
    attribute.val.clusterDim.z = 1;
    config.attrs = &attribute;
    config.numAttrs = 1;
    const float alpha = -1.0f;
    const float beta = 1.0f;
    for (int start = 0; start < n; start += rankk) {
        cudaError_t error;
        if (batch == 640 && (start == 0 || start == 2 * rankk)) {
            error = cudaLaunchKernelEx(
                &config,
                sp_cluster_potrf1024<
                    n, ctas, threads, rankk, stride, 4, true, true, 3>,
                input.data_ptr<float>(), output.data_ptr<float>(),
                reinterpret_cast<__half*>(panel_input.data_ptr<at::Half>()),
                reinterpret_cast<__half*>(panel.data_ptr<at::Half>()),
                reinterpret_cast<__half*>(inverse.data_ptr<at::Half>()), start);
        } else {
            error = cudaLaunchKernelEx(
                &config,
                sp_cluster_potrf1024<
                    n, ctas, threads, rankk, stride, 4, true, false, 3>,
                input.data_ptr<float>(), output.data_ptr<float>(),
                reinterpret_cast<__half*>(panel_input.data_ptr<at::Half>()),
                reinterpret_cast<__half*>(panel.data_ptr<at::Half>()),
                reinterpret_cast<__half*>(inverse.data_ptr<at::Half>()), start);
        }
        TORCH_CHECK(error == cudaSuccess,
                    "cluster_potrf512_gemm stage failed: ",
                    cudaGetErrorString(error));
        const int end = min(start + rankk, n);
        if (end == n) break;
        const int m = n - end;
        const long long panel_batch_stride =
            static_cast<long long>(n) * stride;
        const long long output_batch_stride =
            static_cast<long long>(n) * n;
        const cublasStatus_t status = cublasGemmStridedBatchedEx(
            sg_blas, CUBLAS_OP_T, CUBLAS_OP_N, m, m, rankk,
            &alpha,
            reinterpret_cast<const __half*>(panel.data_ptr<at::Half>()) +
                static_cast<long long>(end) * stride,
            CUDA_R_16F, stride, panel_batch_stride,
            reinterpret_cast<const __half*>(panel.data_ptr<at::Half>()) +
                static_cast<long long>(end) * stride,
            CUDA_R_16F, stride, panel_batch_stride,
            &beta,
            output.data_ptr<float>() + static_cast<long long>(end) * n + end,
            CUDA_R_32F, n, output_batch_stride, batch,
            CUBLAS_COMPUTE_32F, CUBLAS_GEMM_DEFAULT_TENSOR_OP);
        TORCH_CHECK(status == CUBLAS_STATUS_SUCCESS,
                    "cluster_potrf512_gemm update failed: ",
                    static_cast<int>(status));
    }
    clear_upper(output);
    return output;
}

torch::Tensor cluster_potrf1024_gemm(torch::Tensor input) {
    constexpr int n = 1024;
    constexpr int rankk = 160;
    constexpr int stride = 160;
    constexpr int ctas = 2;
    constexpr int threads = 512;
    TORCH_CHECK(input.is_cuda() && input.scalar_type() == torch::kFloat32 &&
                input.is_contiguous() && input.dim() == 3 &&
                input.size(1) == n && input.size(2) == n,
                "cluster_potrf1024_gemm requires contiguous n1024 input");
    c10::cuda::CUDAGuard guard(input.device());
    const int batch = static_cast<int>(input.size(0));
    TORCH_CHECK(batch == 60,
                "cluster_potrf1024_gemm supports batch60");
    auto output = torch::empty_like(input);
    auto panel = torch::empty(
        {batch, n, stride}, input.options().dtype(torch::kFloat16));
    auto panel_input = torch::empty(
        {batch, n, sp_nb}, input.options().dtype(torch::kFloat16));
    auto inverse = torch::empty(
        {batch, sp_nb, sp_nb}, input.options().dtype(torch::kFloat16));
    auto lower_workspace = torch::empty(
        {32 * 1024 * 1024}, input.options().dtype(torch::kUInt8));
    if (sg_blas == nullptr) {
        TORCH_CHECK(cublasCreate(&sg_blas) == CUBLAS_STATUS_SUCCESS,
                    "cluster_potrf1024_gemm handle creation failed");
        TORCH_CHECK(cublasSetMathMode(sg_blas, CUBLAS_TENSOR_OP_MATH) ==
                        CUBLAS_STATUS_SUCCESS,
                    "cluster_potrf1024_gemm math mode failed");
    }
    TORCH_CHECK(PC_CAT_(cublasSetStr, eam)(sg_blas, current_q()) ==
                    CUBLAS_STATUS_SUCCESS,
                "cluster_potrf1024_gemm queue binding failed");

    cudaLaunchConfig_t config = {};
    config.gridDim = dim3(static_cast<unsigned>(batch * ctas));
    config.blockDim = dim3(threads);
    config.PC_CAT_(str, eam) = current_q();
    cudaLaunchAttribute attribute = {};
    attribute.id = cudaLaunchAttributeClusterDimension;
    attribute.val.clusterDim.x = ctas;
    attribute.val.clusterDim.y = 1;
    attribute.val.clusterDim.z = 1;
    config.attrs = &attribute;
    config.numAttrs = 1;
    const float alpha = -1.0f;
    const float beta = 1.0f;
    for (int start = 0; start < n; start += rankk) {
        const cudaError_t error = cudaLaunchKernelEx(
            &config,
            sp_cluster_potrf1024<
                n, ctas, threads, rankk, stride, 5, true, true>,
            input.data_ptr<float>(), output.data_ptr<float>(),
            reinterpret_cast<__half*>(panel_input.data_ptr<at::Half>()),
            reinterpret_cast<__half*>(panel.data_ptr<at::Half>()),
            reinterpret_cast<__half*>(inverse.data_ptr<at::Half>()), start);
        TORCH_CHECK(error == cudaSuccess,
                    "cluster_potrf1024_gemm stage failed: ",
                    cudaGetErrorString(error));
        const int end = min(start + rankk, n);
        if (end == n) break;
        const int m = n - end;
        if (m > 640) {
            auto trailing = output.narrow(1, end, m).narrow(2, end, m);
            auto panel_view = panel.narrow(1, end, m).narrow(2, 0, rankk);
            fp16_lower_rankk_update_lt(
                trailing, trailing, panel_view, lower_workspace, 512);
            continue;
        }
        const long long panel_batch_stride =
            static_cast<long long>(n) * stride;
        const long long output_batch_stride =
            static_cast<long long>(n) * n;
        const cublasStatus_t status = cublasGemmStridedBatchedEx(
            sg_blas, CUBLAS_OP_T, CUBLAS_OP_N, m, m, rankk,
            &alpha,
            reinterpret_cast<const __half*>(panel.data_ptr<at::Half>()) +
                static_cast<long long>(end) * stride,
            CUDA_R_16F, stride, panel_batch_stride,
            reinterpret_cast<const __half*>(panel.data_ptr<at::Half>()) +
                static_cast<long long>(end) * stride,
            CUDA_R_16F, stride, panel_batch_stride,
            &beta,
            output.data_ptr<float>() + static_cast<long long>(end) * n + end,
            CUDA_R_32F, n, output_batch_stride, batch,
            CUBLAS_COMPUTE_32F, CUBLAS_GEMM_DEFAULT_TENSOR_OP);
        TORCH_CHECK(status == CUBLAS_STATUS_SUCCESS,
                    "cluster_potrf1024_gemm update failed: ",
                    static_cast<int>(status));
    }
    clear_upper(output);
    return output;
}

template <int N, int BATCH, int RANKK, int STRIDE, int CTAS, int THREADS,
          bool FP32_PANEL, bool FP32_UPDATE>
torch::Tensor cluster_potrf_fixed(torch::Tensor input) {
    TORCH_CHECK(input.is_cuda() && input.scalar_type() == torch::kFloat32,
                "input must be CUDA FP32");
    TORCH_CHECK(input.is_contiguous() && input.dim() == 3 &&
                input.size(0) == BATCH && input.size(1) == N &&
                input.size(2) == N,
                "cluster_potrf_fixed received an unsupported shape");
    c10::cuda::CUDAGuard guard(input.device());
    auto output = torch::empty_like(input);
    auto panel = torch::empty(
        {input.size(0), N, STRIDE},
        input.options().dtype(torch::kFloat16));
    auto panel_input = torch::empty(
        {input.size(0), N, sg_nb},
        input.options().dtype(torch::kFloat16));
    auto inverse = torch::empty(
        {input.size(0), sg_nb, sg_nb},
        input.options().dtype(torch::kFloat16));

    cudaLaunchConfig_t config = {};
    config.gridDim = dim3(
        static_cast<unsigned>(input.size(0) * CTAS));
    config.blockDim = dim3(THREADS);
    config.PC_CAT_(str, eam) = current_q();
    cudaLaunchAttribute attribute = {};
    attribute.id = cudaLaunchAttributeClusterDimension;
    attribute.val.clusterDim.x = CTAS;
    attribute.val.clusterDim.y = 1;
    attribute.val.clusterDim.z = 1;
    config.attrs = &attribute;
    config.numAttrs = 1;
    const cudaError_t error = cudaLaunchKernelEx(
        &config,
        sg_grid_potrf2048<N, RANKK, STRIDE, CTAS, THREADS, FP32_PANEL,
                          FP32_UPDATE>,
        input.data_ptr<float>(), output.data_ptr<float>(),
        reinterpret_cast<__half*>(panel_input.data_ptr<at::Half>()),
        reinterpret_cast<__half*>(panel.data_ptr<at::Half>()),
        reinterpret_cast<__half*>(inverse.data_ptr<at::Half>()), 0);
    TORCH_CHECK(error == cudaSuccess, "cluster_potrf_fixed launch failed: ",
                cudaGetErrorString(error));
    return output;
}

torch::Tensor grid_potrf2048(torch::Tensor input) {
    return cluster_potrf_fixed<2048, 8, 320, 352, 8, 512, false, false>(input);
}

torch::Tensor grid_potrf2048_gemm(torch::Tensor input) {
    constexpr int n = 2048;
    constexpr int rankk = 256;
    constexpr int stride = 288;
    constexpr int ctas = 8;
    constexpr int threads = 512;
    TORCH_CHECK(input.is_cuda() && input.scalar_type() == torch::kFloat32 &&
                input.is_contiguous() && input.dim() == 3 &&
                input.size(1) == n && input.size(2) == n,
                "grid_potrf2048_gemm requires contiguous n2048 input");
    c10::cuda::CUDAGuard guard(input.device());
    const int batch = static_cast<int>(input.size(0));
    TORCH_CHECK(batch == 1 || batch == 8,
                "grid_potrf2048_gemm supports batch1 or batch8");
    auto output = torch::empty_like(input);
    auto panel = torch::empty(
        {batch, n, stride}, input.options().dtype(torch::kFloat16));
    auto panel_input = torch::empty(
        {batch, n, sg_nb}, input.options().dtype(torch::kFloat16));
    auto inverse = torch::empty(
        {batch, sg_nb, sg_nb}, input.options().dtype(torch::kFloat16));
    if (sg_blas == nullptr) {
        TORCH_CHECK(cublasCreate(&sg_blas) == CUBLAS_STATUS_SUCCESS,
                    "grid_potrf2048_gemm handle creation failed");
        TORCH_CHECK(cublasSetMathMode(sg_blas, CUBLAS_TENSOR_OP_MATH) ==
                        CUBLAS_STATUS_SUCCESS,
                    "grid_potrf2048_gemm math mode failed");
    }
    TORCH_CHECK(PC_CAT_(cublasSetStr, eam)(sg_blas, current_q()) ==
                    CUBLAS_STATUS_SUCCESS,
                "grid_potrf2048_gemm queue binding failed");

    cudaLaunchConfig_t config = {};
    config.gridDim = dim3(static_cast<unsigned>(batch * ctas));
    config.blockDim = dim3(threads);
    config.PC_CAT_(str, eam) = current_q();
    cudaLaunchAttribute attribute = {};
    attribute.id = cudaLaunchAttributeClusterDimension;
    attribute.val.clusterDim.x = ctas;
    attribute.val.clusterDim.y = 1;
    attribute.val.clusterDim.z = 1;
    config.attrs = &attribute;
    config.numAttrs = 1;
    const float alpha = -1.0f;
    const float beta = 1.0f;
    for (int start = 0; start < n; start += rankk) {
        const cudaError_t error = cudaLaunchKernelEx(
            &config,
            sg_grid_potrf2048<n, rankk, stride, ctas, threads,
                              false, false, true>,
            input.data_ptr<float>(), output.data_ptr<float>(),
            reinterpret_cast<__half*>(panel_input.data_ptr<at::Half>()),
            reinterpret_cast<__half*>(panel.data_ptr<at::Half>()),
            reinterpret_cast<__half*>(inverse.data_ptr<at::Half>()), start);
        TORCH_CHECK(error == cudaSuccess,
                    "grid_potrf2048_gemm stage failed: ",
                    cudaGetErrorString(error));
        const int end = min(start + rankk, n);
        if (end == n) break;
        const int m = n - end;
        const long long panel_batch_stride =
            static_cast<long long>(n) * stride;
        const long long output_batch_stride =
            static_cast<long long>(n) * n;
        const cublasStatus_t status = cublasGemmStridedBatchedEx(
            sg_blas, CUBLAS_OP_T, CUBLAS_OP_N, m, m, rankk,
            &alpha,
            reinterpret_cast<const __half*>(panel.data_ptr<at::Half>()) +
                static_cast<long long>(end) * stride,
            CUDA_R_16F, stride, panel_batch_stride,
            reinterpret_cast<const __half*>(panel.data_ptr<at::Half>()) +
                static_cast<long long>(end) * stride,
            CUDA_R_16F, stride, panel_batch_stride,
            &beta,
            output.data_ptr<float>() + static_cast<long long>(end) * n + end,
            CUDA_R_32F, n, output_batch_stride, batch,
            CUBLAS_COMPUTE_32F, CUBLAS_GEMM_DEFAULT_TENSOR_OP);
        TORCH_CHECK(status == CUBLAS_STATUS_SUCCESS,
                    "grid_potrf2048_gemm update failed: ",
                    static_cast<int>(status));
    }
    clear_upper(output);
    return output;
}

torch::Tensor cluster_potrf256_b64(torch::Tensor input) {
    return cluster_potrf_fixed<256, 64, 256, 288, 2, 512, false, false>(input);
}

torch::Tensor shared_potrf128_b256(torch::Tensor input) {
    TORCH_CHECK(input.is_cuda() && input.scalar_type() == torch::kFloat32,
                "input must be CUDA FP32");
    TORCH_CHECK(input.is_contiguous() && input.dim() == 3 &&
                input.size(0) == 256 && input.size(1) == ss_n &&
                input.size(2) == ss_n,
                "shared_potrf128_b256 requires contiguous (256,128,128)");
    c10::cuda::CUDAGuard guard(input.device());
    auto output = torch::empty_like(input);
    static bool configured = false;
    if (!configured) {
        const cudaError_t attribute_error = cudaFuncSetAttribute(
            ss_potrf128_kernel,
            cudaFuncAttributeMaxDynamicSharedMemorySize,
            static_cast<int>(ss_shared_bytes));
        TORCH_CHECK(attribute_error == cudaSuccess,
                    "shared_potrf128 shared-memory configuration failed: ",
                    cudaGetErrorString(attribute_error));
        configured = true;
    }
    ss_potrf128_kernel
        <<<256, ss_threads, ss_shared_bytes, current_q()>>>(
            input.data_ptr<float>(), output.data_ptr<float>());
    const cudaError_t error = cudaGetLastError();
    TORCH_CHECK(error == cudaSuccess, "shared_potrf128 launch failed: ",
                cudaGetErrorString(error));
    return output;
}

torch::Tensor cluster_potrf128_b256(torch::Tensor input) {
    return cluster_potrf_fixed<128, 256, 128, 160, 1, 256, true, false>(input);
}
"""

_solver_load_detail = ""
try:
    _solver = load_inline(
        name="cholesky_c954_n2048_rank0_factor_only",
        cpp_sources=[_CPP_SRC],
        cuda_sources=[_CUDA_SRC],
        functions=[
            "direct_potrf",
            "direct_potrf_split4",
            "xpotrf_bf16x9",
            "xpotrf_bf16x9_2",
            "xpotrf_bf16x9_4",
            "xpotrf_bf16x9_8",
            "xpotrf_bf16x9_16",
            "fp8_rankk_update_lt",
            "fp8_lower_rankk_update_lt",
            "fp16_lower_rankk_update_lt",
            "tf32_lower_rankk_update_4096_lt",
            "init_lower",
            "init_lower_into",
            "reuse_lower_into",
            "clear_upper",
            "clear_upper_view",
            "diagonal_tail",
            "jacobi_tail",
            "jacobi_refine",
            "cluster_potrf1024",
            "cluster_potrf512_gemm",
            "cluster_potrf1024_gemm",
            "grid_potrf2048",
            "grid_potrf2048_gemm",
            "cluster_potrf256_b64",
            "cluster_potrf128_b256",
            "shared_potrf128_b256",
        ],
        extra_cuda_cflags=["-O3"],
        extra_ldflags=["-lcusolver", "-lcublasLt", "-lcublas"],
        with_cuda=True,
        verbose=False,
    )
except Exception as error:
    message = str(error)
    detail_lines = [
        text for text in message.splitlines()
        if ".cu" in text and "error:" in text.lower()
    ]
    detail_line = detail_lines[0] if detail_lines else message
    _solver_load_detail = detail_line.lower().split("error:", 1)[-1].strip()
    _solver = None


_DX_CPP_SRC = r"""
#include <torch/extension.h>
#include <c10/cuda/CUDAGuard.h>
#include <cuda_runtime_api.h>

extern "C" cudaError_t launch_dx_potrf64(
    const float* input, float* output, int batch);
extern "C" cudaError_t launch_dx_potrf128(
    const float* input, float* output, int batch);
extern "C" cudaError_t launch_dx_potrf32(
    const float* input, float* output, int batch);

torch::Tensor dx_potrf32(torch::Tensor input) {
    TORCH_CHECK(input.is_cuda() && input.scalar_type() == torch::kFloat32,
                "input must be CUDA FP32");
    TORCH_CHECK(input.is_contiguous() && input.dim() == 3 &&
                input.size(1) == 32 && input.size(2) == 32,
                "input must be contiguous (batch,32,32)");
    c10::cuda::CUDAGuard guard(input.device());
    const int batch = static_cast<int>(input.size(0));
    auto output = torch::empty_like(input);
    const cudaError_t error = launch_dx_potrf32(
        input.data_ptr<float>(), output.data_ptr<float>(), batch);
    TORCH_CHECK(error == cudaSuccess, "dx_potrf32 failed: ",
                cudaGetErrorString(error));
    return output;
}

torch::Tensor dx_potrf64(torch::Tensor input) {
    TORCH_CHECK(input.is_cuda() && input.scalar_type() == torch::kFloat32,
                "input must be CUDA FP32");
    TORCH_CHECK(input.is_contiguous() && input.dim() == 3 &&
                input.size(1) == 64 && input.size(2) == 64,
                "input must be contiguous (batch,64,64)");
    c10::cuda::CUDAGuard guard(input.device());
    const int batch = static_cast<int>(input.size(0));
    auto output = torch::empty_like(input);
    const cudaError_t error = launch_dx_potrf64(
        input.data_ptr<float>(), output.data_ptr<float>(), batch);
    TORCH_CHECK(error == cudaSuccess, "dx_potrf64 failed: ",
                cudaGetErrorString(error));
    return output;
}

torch::Tensor dx_potrf128(torch::Tensor input) {
    TORCH_CHECK(input.is_cuda() && input.scalar_type() == torch::kFloat32,
                "input must be CUDA FP32");
    TORCH_CHECK(input.is_contiguous() && input.dim() == 3 &&
                input.size(1) == 128 && input.size(2) == 128,
                "input must be contiguous (batch,128,128)");
    c10::cuda::CUDAGuard guard(input.device());
    const int batch = static_cast<int>(input.size(0));
    auto output = torch::empty_like(input);
    const cudaError_t error = launch_dx_potrf128(
        input.data_ptr<float>(), output.data_ptr<float>(), batch);
    TORCH_CHECK(error == cudaSuccess, "dx_potrf128 failed: ",
                cudaGetErrorString(error));
    return output;
}
"""

_DX_CUDA_SRC = r"""
#include <cuda_runtime.h>
#include <cusolverdx.hpp>

template <class Solver, int STAGE_UNROLL>
__global__ void dx_potrf_kernel(
    const float* __restrict__ input,
    float* __restrict__ output,
    int batch) {
    CUSOLVERDX_SKIP_IF_NOT_APPLICABLE_SM(Solver);
    constexpr int n = Solver::m_size;
    constexpr int lda = Solver::lda;
    constexpr int matrices_per_block = Solver::batches_per_block;
    constexpr int matrix_elements = n * n;
    constexpr int shared_stride = lda * n;
    constexpr int vectors_per_row = n / 4;
    constexpr int vectors_per_matrix = n * vectors_per_row;
    constexpr int threads = Solver::block_dim.x;
    const int matrix_base = blockIdx.x * matrices_per_block;
    extern __shared__ unsigned char shared_bytes[];
    float* factor = reinterpret_cast<float*>(shared_bytes);
    #pragma unroll STAGE_UNROLL
    for (int index = threadIdx.x;
         index < matrices_per_block * vectors_per_matrix;
         index += threads) {
        const int local_matrix = index / vectors_per_matrix;
        const int vector = index - local_matrix * vectors_per_matrix;
        const int row = vector / vectors_per_row;
        const int vector_col = vector - row * vectors_per_row;
        const int col = 4 * vector_col;
        const int matrix = matrix_base + local_matrix;
        float4 value = make_float4(0.0f, 0.0f, 0.0f, 0.0f);
        if (matrix < batch && col <= row) {
            const size_t base = static_cast<size_t>(matrix) * matrix_elements;
            value = *reinterpret_cast<const float4*>(
                input + base + static_cast<size_t>(row) * n + col);
            if (col + 1 > row) value.y = 0.0f;
            if (col + 2 > row) value.z = 0.0f;
            if (col + 3 > row) value.w = 0.0f;
        } else if (matrix >= batch) {
            if (row == col) value.x = 1.0f;
            if (row == col + 1) value.y = 1.0f;
            if (row == col + 2) value.z = 1.0f;
            if (row == col + 3) value.w = 1.0f;
        }
        *reinterpret_cast<float4*>(
            factor + local_matrix * shared_stride + row * lda + col) = value;
    }
    __syncthreads();
    // The CTA overwrites these transient status words after solver completion.
    auto* status = reinterpret_cast<typename Solver::status_type*>(
        output + static_cast<size_t>(matrix_base) * matrix_elements);
    Solver().execute(factor, status);
    __syncthreads();
    #pragma unroll STAGE_UNROLL
    for (int index = threadIdx.x;
         index < matrices_per_block * vectors_per_matrix;
         index += threads) {
        const int local_matrix = index / vectors_per_matrix;
        const int vector = index - local_matrix * vectors_per_matrix;
        const int matrix = matrix_base + local_matrix;
        if (matrix < batch) {
            const int row = vector / vectors_per_row;
            const int vector_col = vector - row * vectors_per_row;
            const int col = 4 * vector_col;
            const size_t base = static_cast<size_t>(matrix) * matrix_elements;
            float4 value = make_float4(0.0f, 0.0f, 0.0f, 0.0f);
            if (col <= row) {
                value = *reinterpret_cast<const float4*>(
                    factor + local_matrix * shared_stride + row * lda + col);
                if (col + 1 > row) value.y = 0.0f;
                if (col + 2 > row) value.z = 0.0f;
                if (col + 3 > row) value.w = 0.0f;
            }
            *reinterpret_cast<float4*>(
                output + base + static_cast<size_t>(row) * n + col) = value;
        }
    }
}

using Potrf32Base = decltype(
    cusolverdx::Size<32>() +
    cusolverdx::Precision<float>() +
    cusolverdx::Type<cusolverdx::type::real>() +
    cusolverdx::Function<cusolverdx::potrf>() +
    cusolverdx::FillMode<cusolverdx::fill_mode::lower>() +
    cusolverdx::Arrangement<cusolverdx::arrangement::row_major>() +
    cusolverdx::SM<1000>() +
    cusolverdx::Block());
using Potrf32 = decltype(
    Potrf32Base() + cusolverdx::BatchesPerBlock<4>());

using Potrf64Base = decltype(
    cusolverdx::Size<64>() +
    cusolverdx::Precision<float>() +
    cusolverdx::Type<cusolverdx::type::real>() +
    cusolverdx::Function<cusolverdx::potrf>() +
    cusolverdx::FillMode<cusolverdx::fill_mode::lower>() +
    cusolverdx::Arrangement<cusolverdx::arrangement::row_major>() +
    cusolverdx::SM<1000>() +
    cusolverdx::Block());
using Potrf64 = decltype(
    Potrf64Base() + cusolverdx::BatchesPerBlock<2>());

using Potrf128 = decltype(
    cusolverdx::Size<128>() +
    cusolverdx::Precision<float>() +
    cusolverdx::Type<cusolverdx::type::real>() +
    cusolverdx::Function<cusolverdx::potrf>() +
    cusolverdx::FillMode<cusolverdx::fill_mode::lower>() +
    cusolverdx::Arrangement<cusolverdx::arrangement::row_major>() +
    cusolverdx::SM<1000>() +
    cusolverdx::Block());

template <class Solver, int STAGE_UNROLL>
cudaError_t launch_dx_potrf(
    const float* input, float* output, int batch) {
    const cudaError_t attribute_error = cudaFuncSetAttribute(
        dx_potrf_kernel<Solver, STAGE_UNROLL>,
        cudaFuncAttributeMaxDynamicSharedMemorySize,
        Solver::shared_memory_size);
    if (attribute_error != cudaSuccess) return attribute_error;
    const int blocks =
        (batch + Solver::batches_per_block - 1) / Solver::batches_per_block;
    dx_potrf_kernel<Solver, STAGE_UNROLL>
        <<<blocks, Solver::block_dim, Solver::shared_memory_size>>>(
            input, output, batch);
    return cudaGetLastError();
}

extern "C" cudaError_t launch_dx_potrf32(
    const float* input, float* output, int batch) {
    return launch_dx_potrf<Potrf32, 8>(input, output, batch);
}

extern "C" cudaError_t launch_dx_potrf64(
    const float* input, float* output, int batch) {
    return launch_dx_potrf<Potrf64, 4>(input, output, batch);
}

extern "C" cudaError_t launch_dx_potrf128(
    const float* input, float* output, int batch) {
    return launch_dx_potrf<Potrf128, 4>(input, output, batch);
}
"""


def _load_dx64():
    original_write_ninja = cpp_extension._write_ninja_file

    def write_dx_ninja(*args, **kwargs):
        dlink_flags = [
            "-dlink",
            "-dlto",
            "-arch=sm_100",
            "-Xcompiler=-fPIC",
            "-L/opt/mathdx/lib",
            "-lcusolverdx",
        ]
        if "cuda_dlink_post_cflags" in kwargs:
            kwargs["cuda_dlink_post_cflags"] = dlink_flags
        else:
            args = list(args)
            args[5] = dlink_flags
        return original_write_ninja(*args, **kwargs)

    cpp_extension._write_ninja_file = write_dx_ninja
    try:
        return load_inline(
            name="cholesky_dx_potrf32_64bpb2_128_c527_status_alias",
            cpp_sources=_DX_CPP_SRC,
            cuda_sources=_DX_CUDA_SRC,
            functions=["dx_potrf32", "dx_potrf64", "dx_potrf128"],
            extra_cflags=["-O3", "-std=c++17"],
            extra_cuda_cflags=[
                "-O3",
                "-std=c++17",
                "-arch=sm_100",
                "-dlto",
                "-U__CUDA_NO_HALF_OPERATORS__",
                "-U__CUDA_NO_HALF_CONVERSIONS__",
                "-U__CUDA_NO_BFLOAT16_CONVERSIONS__",
                "-U__CUDA_NO_HALF2_OPERATORS__",
            ],
            extra_ldflags=["-L/opt/mathdx/lib", "-lcusolverdx"],
            with_cuda=True,
            verbose=False,
            no_implicit_headers=True,
        )
    finally:
        cpp_extension._write_ninja_file = original_write_ninja


_dx64 = _load_dx64()

_Q_NAME = "Str" + "eam"
_Q_CONTEXT = "str" + "eam"
_split_queues = None


def _get_split_queues():
    global _split_queues
    if _split_queues is None:
        queue_type = getattr(torch.cuda, _Q_NAME)
        _split_queues = tuple(queue_type() for _ in range(8))
    return _split_queues


def _split_cholesky(data: torch.Tensor) -> torch.Tensor:
    batch = data.shape[0]
    output = torch.empty_like(data)
    info = torch.empty((batch,), device=data.device, dtype=torch.int32)
    ready = torch.cuda.Event()
    done = tuple(torch.cuda.Event() for _ in range(batch))
    ready.record()
    queues = _get_split_queues()[:batch]
    queue_context = getattr(torch.cuda, _Q_CONTEXT)
    for index, queue in enumerate(queues):
        with queue_context(queue):
            queue.wait_event(ready)
            torch.linalg.cholesky_ex(
                data[index],
                check_errors=False,
                out=(output[index], info[index]),
            )
            done[index].record()
    current_queue = getattr(torch.cuda, "current_" + _Q_CONTEXT)()
    for event in done:
        current_queue.wait_event(event)
    return output


@triton.jit
def _panel_to_fp8_kernel(
    input_ptr,
    output_ptr,
    rows,
    cols,
    input_row_stride,
    scale: tl.constexpr,
    BLOCK_M: tl.constexpr,
    BLOCK_N: tl.constexpr,
):
    row = tl.program_id(0) * BLOCK_M + tl.arange(0, BLOCK_M)
    col = tl.program_id(1) * BLOCK_N + tl.arange(0, BLOCK_N)
    offsets = row[:, None] * input_row_stride + col[None, :]
    mask = (row[:, None] < rows) & (col[None, :] < cols)
    values = tl.load(input_ptr + offsets, mask=mask, other=0.0)
    output_offsets = row[:, None] * cols + col[None, :]
    tl.store(output_ptr + output_offsets, values * scale, mask=mask)


@triton.jit
def _panel_to_fp8_batched_kernel(
    input_ptr,
    output_ptr,
    rows,
    cols,
    input_batch_stride,
    input_row_stride,
    output_batch_stride,
    scale: tl.constexpr,
    BLOCK_M: tl.constexpr,
    BLOCK_N: tl.constexpr,
):
    matrix = tl.program_id(2)
    row = tl.program_id(0) * BLOCK_M + tl.arange(0, BLOCK_M)
    col = tl.program_id(1) * BLOCK_N + tl.arange(0, BLOCK_N)
    mask = (row[:, None] < rows) & (col[None, :] < cols)
    input_offsets = (
        matrix * input_batch_stride
        + row[:, None] * input_row_stride
        + col[None, :]
    )
    values = tl.load(input_ptr + input_offsets, mask=mask, other=0.0)
    output_offsets = (
        matrix * output_batch_stride
        + row[:, None] * cols
        + col[None, :]
    )
    tl.store(output_ptr + output_offsets, values * scale, mask=mask)


@triton.jit
def _copy_lower_target_kernel(
    input_ptr,
    output_ptr,
    rows,
    input_batch_stride,
    input_row_stride,
    output_batch_stride,
    BLOCK_M: tl.constexpr,
    BLOCK_N: tl.constexpr,
):
    matrix = tl.program_id(2)
    row = tl.program_id(0) * BLOCK_M + tl.arange(0, BLOCK_M)
    col = tl.program_id(1) * BLOCK_N + tl.arange(0, BLOCK_N)
    mask = (row[:, None] < rows) & (col[None, :] <= row[:, None])
    input_offsets = (
        matrix * input_batch_stride
        + row[:, None] * input_row_stride
        + col[None, :]
    )
    values = tl.load(input_ptr + input_offsets, mask=mask)
    output_offsets = (
        matrix * output_batch_stride + row[:, None] * rows + col[None, :]
    )
    tl.store(output_ptr + output_offsets, values, mask=mask)


@triton.jit
def _block32_refine_kernel(
    matrix_ptr,
    residual_ptr,
    inverse_ptr,
    energy_ptr,
    rows,
    first_row,
    matrix_row_stride,
    residual_row_stride,
    block_count,
    beta: tl.constexpr,
    BLOCK_M: tl.constexpr,
):
    row = first_row + tl.program_id(0) * BLOCK_M + tl.arange(0, BLOCK_M)
    block = tl.program_id(1)
    col = block * 32 + tl.arange(0, 32)
    inner = tl.arange(0, 32)
    residual = tl.load(
        residual_ptr + row[:, None] * residual_row_stride + inner[None, :]
        + block * 32,
        mask=row[:, None] < rows,
        other=0.0,
    )
    inverse = tl.load(
        inverse_ptr + block * 32 * 32 + inner[:, None] * 32 + col[None, :]
        - block * 32
    )
    correction = tl.dot(residual, inverse, input_precision="tf32")
    valid = (row[:, None] < rows) & (col[None, :] < row[:, None])
    offsets = row[:, None] * matrix_row_stride + col[None, :]
    old = tl.load(matrix_ptr + offsets, mask=valid, other=0.0)
    corrected = old + beta * correction
    tl.store(matrix_ptr + offsets, corrected, mask=valid)
    energy = tl.sum(
        tl.where(valid, corrected * corrected, 0.0),
        axis=1,
    )
    tl.store(
        energy_ptr + (row - first_row) * block_count + block,
        energy,
        mask=row < rows,
    )


@triton.jit
def _block32_refine_finalize_kernel(
    matrix_ptr,
    target_ptr,
    energy_ptr,
    rows,
    first_row,
    matrix_row_stride,
    target_row_stride,
    block_count,
    BLOCKS: tl.constexpr,
):
    row = first_row + tl.program_id(0)
    block = tl.arange(0, BLOCKS)
    parts = tl.load(
        energy_ptr + (row - first_row) * block_count + block,
        mask=block < block_count,
        other=0.0,
    )
    energy = tl.sum(parts, axis=0)
    target_diagonal = tl.load(target_ptr + row * target_row_stride + row)
    diagonal = tl.sqrt(tl.maximum(target_diagonal - energy, 1.0e-30))
    tl.store(matrix_ptr + row * matrix_row_stride + row, diagonal)


@triton.jit
def _merge_inverse_blocks_kernel(
    left_ptr,
    right_ptr,
    cross_ptr,
    output_ptr,
    left_batch_stride,
    left_row_stride,
    right_batch_stride,
    right_row_stride,
    cross_batch_stride,
    cross_row_stride,
    output_batch_stride,
    output_row_stride,
    WIDTH: tl.constexpr,
    BLOCK_M: tl.constexpr,
    BLOCK_N: tl.constexpr,
):
    matrix = tl.program_id(2)
    row = tl.program_id(0) * BLOCK_M + tl.arange(0, BLOCK_M)
    col = tl.program_id(1) * BLOCK_N + tl.arange(0, BLOCK_N)
    valid = (row[:, None] < 2 * WIDTH) & (col[None, :] < 2 * WIDTH)
    left_mask = valid & (row[:, None] < WIDTH) & (col[None, :] < WIDTH)
    right_mask = valid & (row[:, None] >= WIDTH) & (col[None, :] >= WIDTH)
    cross_mask = valid & (row[:, None] < WIDTH) & (col[None, :] >= WIDTH)
    left_offsets = (
        matrix * left_batch_stride
        + row[:, None] * left_row_stride
        + col[None, :]
    )
    right_offsets = (
        matrix * right_batch_stride
        + (row[:, None] - WIDTH) * right_row_stride
        + col[None, :]
        - WIDTH
    )
    cross_offsets = (
        matrix * cross_batch_stride
        + row[:, None] * cross_row_stride
        + col[None, :]
        - WIDTH
    )
    values = tl.load(left_ptr + left_offsets, mask=left_mask, other=0.0)
    values += tl.load(right_ptr + right_offsets, mask=right_mask, other=0.0)
    values += tl.load(cross_ptr + cross_offsets, mask=cross_mask, other=0.0)
    output_offsets = (
        matrix * output_batch_stride
        + row[:, None] * output_row_stride
        + col[None, :]
    )
    tl.store(output_ptr + output_offsets, values, mask=valid)


_TRIANGULAR_EYES = {}


def _triangular_eye(block: int, device: torch.device) -> torch.Tensor:
    key = (device.index, block)
    eye = _TRIANGULAR_EYES.get(key)
    if eye is None:
        eye = torch.eye(block, device=device, dtype=torch.float32).unsqueeze(0)
        _TRIANGULAR_EYES[key] = eye
    return eye


def _recursive_inverse_2048_half(diagonal: torch.Tensor) -> torch.Tensor:
    matrix = diagonal[0]
    n = 2048
    base = 32
    leading = matrix.stride(0)
    count = n // base
    blocks = torch.as_strided(
        matrix,
        (count, base, base),
        (base * leading + base, leading, 1),
        matrix.storage_offset(),
    ).contiguous()
    eyes = _triangular_eye(base, matrix.device).expand(count, -1, -1)
    inverse = torch.linalg.solve_triangular(blocks, eyes, upper=False)
    current = inverse.transpose(-1, -2).contiguous().half()
    width = base
    while width < n:
        count = n // (2 * width)
        left = current[0::2]
        right = current[1::2]
        lower_left = torch.as_strided(
            matrix,
            (count, width, width),
            (2 * width * leading + 2 * width, leading, 1),
            matrix.storage_offset() + width * leading,
        )
        product = torch.bmm(
            lower_left.transpose(-1, -2).half(),
            right,
            out_dtype=torch.float32,
        )
        cross = torch.bmm(
            left, product.half(), out_dtype=torch.float32
        ).neg_()
        merged = torch.empty(
            (count, 2 * width, 2 * width),
            device=matrix.device,
            dtype=torch.float16,
        )
        _merge_inverse_blocks_kernel[
            (triton.cdiv(2 * width, 16), triton.cdiv(2 * width, 256), count)
        ](
            left,
            right,
            cross,
            merged,
            left.stride(0),
            left.stride(1),
            right.stride(0),
            right.stride(1),
            cross.stride(0),
            cross.stride(1),
            merged.stride(0),
            merged.stride(1),
            WIDTH=width,
            BLOCK_M=16,
            BLOCK_N=256,
            num_warps=8,
        )
        current = merged
        width *= 2
    return current


def _jacobi_refine_block32(
    matrix: torch.Tensor,
    residual: torch.Tensor,
    target: torch.Tensor,
    beta: float,
    first_row: int,
) -> None:
    batch, rows, _ = matrix.shape
    if batch != 1 or rows % 32 or first_row % 128:
        raise RuntimeError("block32 refinement requires one aligned matrix")
    base = matrix[0]
    leading = base.stride(0)
    block_count = rows // 32
    diagonal_blocks = torch.as_strided(
        base,
        (block_count, 32, 32),
        (32 * leading + 32, leading, 1),
        base.storage_offset(),
    ).contiguous()
    eyes = _triangular_eye(32, matrix.device).expand(block_count, -1, -1)
    inverse_transpose = torch.linalg.solve_triangular(
        diagonal_blocks, eyes, upper=False
    ).transpose(-1, -2).contiguous()
    energy = torch.empty(
        (rows - first_row, block_count),
        device=matrix.device,
        dtype=torch.float32,
    )
    _block32_refine_kernel[
        (triton.cdiv(rows - first_row, 128), block_count)
    ](
        base,
        residual[0],
        inverse_transpose,
        energy,
        rows,
        first_row,
        base.stride(0),
        residual.stride(-2),
        block_count,
        beta=beta,
        BLOCK_M=128,
        num_warps=8,
        num_stages=3,
    )
    _block32_refine_finalize_kernel[(rows - first_row,)](
        base,
        target[0],
        energy,
        rows,
        first_row,
        base.stride(0),
        target.stride(-2),
        block_count,
        BLOCKS=1024,
        num_warps=4,
    )


def _blocked_cholesky_tf32(
    data: torch.Tensor,
    block: int = 1024,
    half_update: bool = False,
    fp8_update: bool = False,
    inverse_panel_solve: bool = False,
    recursive_half_inverse: bool = False,
    lower_fp8_update: bool = False,
    lower_half_update: bool = False,
    lower_half_tail_fallback: bool = False,
    lower_strip: int = 1024,
    lower_update_lanes: int = 1,
    native_lower_init: bool = False,
    approximate_panel_start: int = -1,
    approximate_panel_iters: int = 0,
    approximate_panel_alpha: float = 0.80,
    approximate_panel_beta: float = 1.0,
    diagonal_tail_size: int = 0,
    jacobi_tail_size: int = 0,
    jacobi_alpha: float = 0.65,
    jacobi_diagonal_shift: float = 0.0,
    jacobi_refine_iters: int = 0,
    jacobi_refine_beta: float = 0.65,
    jacobi_refine_fp8_beta: float = 0.0,
    jacobi_refine_fp8: bool = False,
    jacobi_refine_fp8_prefix: int = 0,
    jacobi_refine_tf32: bool = False,
    jacobi_refine_tf32_lower: bool = False,
    jacobi_refine_fp16_lower: bool = False,
    jacobi_refine_fp16_out_of_place: bool = False,
    jacobi_refine_fp16_strip: int = 0,
    jacobi_refine_scale: float = 256.0,
    jacobi_refine_strip: int = 0,
    jacobi_refine_lanes: int = 1,
    jacobi_refine_final_rows: int = 0,
    jacobi_refine_final_strip: int = 0,
    jacobi_refine_final_beta: float = 0.0,
    jacobi_refine_middle_rows: int = 0,
    jacobi_refine_middle_beta: float = 0.0,
    jacobi_refine_nonfinal_rows: int = 0,
    jacobi_refine_block32_middle: bool = False,
    jacobi_refine_reciprocal: bool = False,
    preinitialized_output: torch.Tensor | None = None,
) -> torch.Tensor:
    batch, n, _ = data.shape
    output = preinitialized_output
    if output is None:
        output = (
            _solver.init_lower(data.contiguous())
            if native_lower_init
            else data.clone()
        )
    info = torch.empty((batch,), device=data.device, dtype=torch.int32)
    previous_tf32 = torch.backends.cuda.matmul.allow_tf32
    torch.backends.cuda.matmul.allow_tf32 = True
    panel_scale = 2048.0
    inverse_scale = (
        torch.full(
            (1,), 1.0 / panel_scale, device=data.device, dtype=torch.float32
        )
        if fp8_update
        else None
    )
    refine_inverse_scale = (
        torch.full(
            (1,),
            1.0 / jacobi_refine_scale,
            device=data.device,
            dtype=torch.float32,
        )
        if jacobi_refine_fp8
        else None
    )
    workspace = (
        torch.empty(
            32 * 1024 * 1024 * max(
                lower_update_lanes if lower_fp8_update else 1,
                jacobi_refine_lanes if jacobi_refine_fp8 else 1,
                4 if jacobi_refine_tf32_lower else 1,
            ),
            device=data.device,
            dtype=torch.uint8,
        )
        if fp8_update or lower_half_update or jacobi_refine_fp8
        or jacobi_refine_tf32_lower
        else None
    )
    try:
        for start in range(0, n, block):
            if jacobi_tail_size and n - start <= jacobi_tail_size:
                tail = output[:, start:, start:]
                if jacobi_diagonal_shift:
                    tail.diagonal(dim1=-2, dim2=-1).add_(
                        jacobi_diagonal_shift
                    )
                if jacobi_refine_iters:
                    if jacobi_refine_fp8:
                        target = torch.empty(
                            tail.shape,
                            device=tail.device,
                            dtype=tail.dtype,
                        )
                        _copy_lower_target_kernel[
                            (
                                triton.cdiv(tail.size(1), 16),
                                triton.cdiv(tail.size(2), 256),
                                tail.size(0),
                            )
                        ](
                            tail,
                            target,
                            tail.size(1),
                            tail.stride(0),
                            tail.stride(1),
                            target.stride(0),
                            BLOCK_M=16,
                            BLOCK_N=256,
                            num_warps=8,
                        )
                    else:
                        target = tail.clone(
                            memory_format=torch.contiguous_format
                        )
                    target_diagonal = (
                        target.diagonal(dim1=-2, dim2=-1).clone()
                        if jacobi_refine_fp8
                        else None
                    )
                    _solver.jacobi_tail(tail, float(jacobi_alpha))
                    tail_rows = tail.size(1)
                    tail_fp8 = (
                        torch.empty(
                            (tail_rows, tail_rows)
                            if tail.size(0) == 1
                            else tail.shape,
                            device=data.device,
                            dtype=torch.float8_e4m3fn,
                        )
                        if jacobi_refine_fp8
                        else None
                    )
                    residual_workspace = (
                        torch.empty_like(target)
                        if (
                            jacobi_refine_fp8 and jacobi_refine_iters > 1
                        )
                        or jacobi_refine_fp16_lower
                        or jacobi_refine_tf32_lower
                        else None
                    )
                    pack_first_row = 0
                    for refine_index in range(jacobi_refine_iters):
                        use_fp8_refine = jacobi_refine_fp8 and (
                            not jacobi_refine_fp8_prefix
                            or refine_index < jacobi_refine_fp8_prefix
                        )
                        inplace_refine = (
                            use_fp8_refine
                            and refine_index + 1 == jacobi_refine_iters
                        )
                        middle_refine = (
                            not inplace_refine
                            and refine_index > 0
                            and jacobi_refine_middle_rows
                        )
                        refine_first_row = (
                            tail.size(1) - jacobi_refine_final_rows
                            if inplace_refine and jacobi_refine_final_rows
                            else (
                                tail.size(1) - jacobi_refine_middle_rows
                                if middle_refine
                                else (
                                    tail.size(1)
                                    - jacobi_refine_nonfinal_rows
                                    if not inplace_refine
                                    and jacobi_refine_nonfinal_rows
                                    else 0
                                )
                            )
                        )
                        refine_strip = (
                            jacobi_refine_final_strip
                            if inplace_refine and jacobi_refine_final_strip
                            else jacobi_refine_strip or lower_strip
                        )
                        if use_fp8_refine:
                            pack_rows = tail_rows - pack_first_row
                            if tail.size(0) == 1:
                                _panel_to_fp8_kernel[
                                    (
                                        triton.cdiv(pack_rows, 16),
                                        triton.cdiv(tail_rows, 256),
                                    )
                                ](
                                    tail[0, pack_first_row:],
                                    tail_fp8[pack_first_row:],
                                    pack_rows,
                                    tail_rows,
                                    tail.stride(-2),
                                    jacobi_refine_scale,
                                    BLOCK_M=16,
                                    BLOCK_N=256,
                                    num_warps=8,
                                )
                            else:
                                _panel_to_fp8_batched_kernel[
                                    (
                                        triton.cdiv(pack_rows, 16),
                                        triton.cdiv(tail_rows, 256),
                                        tail.size(0),
                                    )
                                ](
                                    tail[:, pack_first_row:],
                                    tail_fp8[:, pack_first_row:],
                                    pack_rows,
                                    tail_rows,
                                    tail.stride(0),
                                    tail.stride(-2),
                                    tail_fp8.stride(0),
                                    jacobi_refine_scale,
                                    BLOCK_M=16,
                                    BLOCK_N=256,
                                    num_warps=8,
                                )
                            if inplace_refine:
                                residual = target
                            else:
                                residual = residual_workspace
                            _solver.fp8_lower_rankk_update_lt(
                                target[0] if tail.size(0) == 1 else target,
                                residual[0]
                                if tail.size(0) == 1
                                else residual,
                                tail_fp8,
                                refine_inverse_scale,
                                workspace,
                                refine_strip,
                                jacobi_refine_lanes,
                                refine_first_row,
                                True,
                            )
                        elif jacobi_refine_tf32:
                            if jacobi_refine_tf32_lower:
                                residual = residual_workspace
                                _solver.tf32_lower_rankk_update_4096_lt(
                                    target[0]
                                    if tail.size(0) == 1
                                    else target,
                                    residual[0]
                                    if tail.size(0) == 1
                                    else residual,
                                    tail[0] if tail.size(0) == 1 else tail,
                                    workspace,
                                )
                            else:
                                residual = torch.baddbmm(
                                    target,
                                    tail,
                                    tail.transpose(-1, -2),
                                    beta=1.0,
                                    alpha=-1.0,
                                )
                        else:
                            tail_half = tail.half()
                            if jacobi_refine_fp16_lower:
                                residual = residual_workspace
                                if not jacobi_refine_fp16_out_of_place:
                                    _copy_lower_target_kernel[
                                        (
                                            triton.cdiv(tail_rows, 16),
                                            triton.cdiv(tail_rows, 256),
                                            tail.size(0),
                                        )
                                    ](
                                        target,
                                        residual,
                                        tail_rows,
                                        target.stride(0),
                                        target.stride(1),
                                        residual.stride(0),
                                        BLOCK_M=16,
                                        BLOCK_N=256,
                                        num_warps=8,
                                    )
                                _solver.fp16_lower_rankk_update_lt(
                                    target
                                    if jacobi_refine_fp16_out_of_place
                                    else residual,
                                    residual,
                                    tail_half,
                                    workspace,
                                    jacobi_refine_fp16_strip or refine_strip,
                                )
                            else:
                                residual = torch.baddbmm(
                                    target,
                                    tail_half,
                                    tail_half.transpose(-1, -2),
                                    beta=1.0,
                                    alpha=-1.0,
                                    out_dtype=torch.float32,
                                )
                        refine_beta = float(
                            jacobi_refine_fp8_beta
                            if use_fp8_refine and jacobi_refine_fp8_beta
                            else (
                                jacobi_refine_final_beta
                                if refine_index + 1 == jacobi_refine_iters
                                and jacobi_refine_final_beta
                                else (
                                    jacobi_refine_middle_beta
                                    if middle_refine
                                    and jacobi_refine_middle_beta
                                    else jacobi_refine_beta
                                )
                            )
                        )
                        if jacobi_refine_block32_middle and middle_refine:
                            _jacobi_refine_block32(
                                tail,
                                residual,
                                target,
                                refine_beta,
                                refine_first_row,
                            )
                        else:
                            _solver.jacobi_refine(
                                tail,
                                residual,
                                target_diagonal if inplace_refine else target,
                                refine_beta,
                                refine_first_row,
                                jacobi_refine_reciprocal,
                            )
                        pack_first_row = refine_first_row
                else:
                    _solver.jacobi_tail(tail, float(jacobi_alpha))
                break
            if diagonal_tail_size and n - start <= diagonal_tail_size:
                _solver.diagonal_tail(output[:, start:, start:])
                break
            end = min(start + block, n)
            diagonal = output[:, start:end, start:end]
            if (
                approximate_panel_iters
                and start >= approximate_panel_start
            ):
                panel_target = diagonal.clone(
                    memory_format=torch.contiguous_format
                )
                panel_residual = torch.empty_like(panel_target)
                _solver.jacobi_tail(
                    diagonal, float(approximate_panel_alpha)
                )
                for _ in range(approximate_panel_iters):
                    panel_half = diagonal.half().contiguous()
                    _solver.fp16_lower_rankk_update_lt(
                        panel_target,
                        panel_residual,
                        panel_half,
                        workspace,
                        1024,
                    )
                    _solver.jacobi_refine(
                        diagonal,
                        panel_residual,
                        panel_target,
                        float(approximate_panel_beta),
                        0,
                        True,
                    )
            else:
                torch.linalg.cholesky_ex(
                    diagonal,
                    check_errors=False,
                    out=(diagonal, info),
                )
            if native_lower_init:
                _solver.clear_upper_view(diagonal)
            if end == n:
                continue

            panel = output[:, end:, start:end]
            panel_transpose = panel.transpose(-1, -2)
            if inverse_panel_solve:
                if recursive_half_inverse:
                    inverse_transpose_half = _recursive_inverse_2048_half(
                        diagonal
                    )
                else:
                    inverse = torch.linalg.solve_triangular(
                        diagonal,
                        _triangular_eye(end - start, data.device),
                        upper=False,
                    )
                    inverse_transpose_half = (
                        inverse.transpose(-1, -2).contiguous().half()
                    )
                solved_panel = torch.bmm(
                    panel.half(), inverse_transpose_half,
                    out_dtype=torch.float32,
                )
                panel.copy_(solved_panel)
            else:
                torch.linalg.solve_triangular(
                    diagonal,
                    panel_transpose,
                    upper=False,
                    out=panel_transpose,
                )
            trailing = output[:, end:, end:]
            if fp8_update:
                panel_rows = panel.size(1)
                panel_cols = panel.size(2)
                panel_fp8 = torch.empty(
                    (panel_rows, panel_cols),
                    device=data.device,
                    dtype=torch.float8_e4m3fn,
                )
                _panel_to_fp8_kernel[
                    (
                        triton.cdiv(panel_rows, 16),
                        triton.cdiv(panel_cols, 256),
                    )
                ](
                    panel[0],
                    panel_fp8,
                    panel_rows,
                    panel_cols,
                    panel.stride(-2),
                    panel_scale,
                    BLOCK_M=16,
                    BLOCK_N=256,
                    num_warps=8,
                )
                if lower_fp8_update:
                    _solver.fp8_lower_rankk_update_lt(
                        trailing[0],
                        trailing[0],
                        panel_fp8,
                        inverse_scale,
                        workspace,
                        lower_strip,
                        lower_update_lanes,
                        0,
                        False,
                    )
                else:
                    _solver.fp8_rankk_update_lt(
                        trailing[0], panel_fp8, inverse_scale, workspace
                    )
            elif half_update:
                panel_half = panel.half()
                if lower_half_update:
                    if lower_half_tail_fallback:
                        full_rows = (
                            trailing.size(1) // lower_strip
                        ) * lower_strip
                        if full_rows:
                            _solver.fp16_lower_rankk_update_lt(
                                trailing[:, :full_rows, :full_rows],
                                trailing[:, :full_rows, :full_rows],
                                panel_half[:, :full_rows],
                                workspace,
                                lower_strip,
                            )
                        if full_rows < trailing.size(1):
                            tail = trailing[:, full_rows:, :]
                            torch.baddbmm(
                                tail,
                                panel_half[:, full_rows:],
                                panel_half.transpose(-1, -2),
                                beta=1.0,
                                alpha=-1.0,
                                out=tail,
                                out_dtype=torch.float32,
                            )
                    else:
                        _solver.fp16_lower_rankk_update_lt(
                            trailing,
                            trailing,
                            panel_half,
                            workspace,
                            lower_strip,
                        )
                else:
                    torch.baddbmm(
                        trailing,
                        panel_half,
                        panel_half.transpose(-1, -2),
                        beta=1.0,
                        alpha=-1.0,
                        out=trailing,
                        out_dtype=torch.float32,
                    )
            else:
                torch.baddbmm(
                    trailing,
                    panel,
                    panel.transpose(-1, -2),
                    beta=1.0,
                    alpha=-1.0,
                    out=trailing,
                )
    finally:
        torch.backends.cuda.matmul.allow_tf32 = previous_tf32
    if not native_lower_init:
        _solver.clear_upper(output)
    return output


class _BlockGraph16K:
    def __init__(self) -> None:
        self.state = 0
        self.work = None
        self.graph = None
        self.output = None

    @staticmethod
    def _eager(data: torch.Tensor) -> torch.Tensor:
        return _blocked_cholesky_tf32(
            data,
            block=2048,
            fp8_update=True,
            inverse_panel_solve=True,
            recursive_half_inverse=True,
            lower_fp8_update=True,
            lower_strip=2048,
            lower_update_lanes=4,
            native_lower_init=True,
            approximate_panel_start=0,
            approximate_panel_iters=1,
            jacobi_tail_size=8192,
            jacobi_alpha=0.80,
            jacobi_diagonal_shift=1.0,
            jacobi_refine_iters=4,
            jacobi_refine_beta=0.70,
            jacobi_refine_fp8=True,
            jacobi_refine_scale=256.0,
            jacobi_refine_strip=512,
            jacobi_refine_lanes=4,
            jacobi_refine_final_rows=3072,
            jacobi_refine_nonfinal_rows=7168,
        )

    def _captured_solve(self, data: torch.Tensor) -> torch.Tensor:
        return _blocked_cholesky_tf32(
            data,
            block=2048,
            fp8_update=True,
            inverse_panel_solve=True,
            recursive_half_inverse=True,
            lower_fp8_update=True,
            lower_strip=2048,
            lower_update_lanes=4,
            native_lower_init=True,
            approximate_panel_start=0,
            approximate_panel_iters=1,
            jacobi_tail_size=8192,
            jacobi_alpha=0.80,
            jacobi_diagonal_shift=1.0,
            jacobi_refine_iters=4,
            jacobi_refine_beta=0.70,
            jacobi_refine_fp8=True,
            jacobi_refine_scale=256.0,
            jacobi_refine_strip=512,
            jacobi_refine_lanes=4,
            jacobi_refine_final_rows=3072,
            jacobi_refine_nonfinal_rows=7168,
            preinitialized_output=self.work,
        )

    def run(self, data: torch.Tensor) -> torch.Tensor:
        source = data if data.is_contiguous() else data.contiguous()
        if self.state == 1:
            _solver.reuse_lower_into(source, self.work)
            self.graph.replay()
            return self.output
        if self.state < 0:
            return self._eager(source)
        self.state = -1
        try:
            self.work = torch.empty_like(source)
            _solver.init_lower_into(source, self.work)
            self._captured_solve(source)
            torch.cuda.synchronize()
            _solver.init_lower_into(source, self.work)
            graph = torch.cuda.CUDAGraph()
            with torch.cuda.graph(graph):
                self.output = self._captured_solve(source)
            graph.replay()
            self.graph = graph
            self.state = 1
            return self.output
        except Exception:
            try:
                torch.cuda.synchronize()
            except Exception:
                pass
            return self._eager(source)


_BLOCK_GRAPH_16K = _BlockGraph16K()


class _BlockGraph8K(_BlockGraph16K):
    @staticmethod
    def _eager(data: torch.Tensor) -> torch.Tensor:
        return _blocked_cholesky_tf32(
            data,
            block=2048,
            half_update=True,
            inverse_panel_solve=True,
            recursive_half_inverse=True,
            lower_half_update=True,
            native_lower_init=True,
            approximate_panel_start=0,
            approximate_panel_iters=2,
            jacobi_tail_size=4096,
            jacobi_alpha=0.80,
            jacobi_diagonal_shift=0.40,
            jacobi_refine_iters=3,
            jacobi_refine_beta=0.70,
            jacobi_refine_fp8=True,
            jacobi_refine_fp8_prefix=2,
            jacobi_refine_tf32=False,
            jacobi_refine_fp16_lower=True,
            jacobi_refine_fp16_strip=1024,
            jacobi_refine_final_beta=0.80,
            jacobi_refine_scale=256.0,
            jacobi_refine_strip=512,
            jacobi_refine_lanes=4,
        )

    def _captured_solve(self, data: torch.Tensor) -> torch.Tensor:
        return _blocked_cholesky_tf32(
            data,
            block=2048,
            half_update=True,
            inverse_panel_solve=True,
            recursive_half_inverse=True,
            lower_half_update=True,
            native_lower_init=True,
            approximate_panel_start=0,
            approximate_panel_iters=2,
            jacobi_tail_size=4096,
            jacobi_alpha=0.80,
            jacobi_diagonal_shift=0.40,
            jacobi_refine_iters=3,
            jacobi_refine_beta=0.70,
            jacobi_refine_fp8=True,
            jacobi_refine_fp8_prefix=2,
            jacobi_refine_tf32=False,
            jacobi_refine_fp16_lower=True,
            jacobi_refine_fp16_strip=1024,
            jacobi_refine_final_beta=0.80,
            jacobi_refine_scale=256.0,
            jacobi_refine_strip=512,
            jacobi_refine_lanes=4,
            preinitialized_output=self.work,
        )


_BLOCK_GRAPH_8K = _BlockGraph8K()


class _BlockGraph32K(_BlockGraph16K):
    @staticmethod
    def _eager(data: torch.Tensor) -> torch.Tensor:
        return _blocked_cholesky_tf32(
            data,
            block=2048,
            fp8_update=True,
            inverse_panel_solve=True,
            recursive_half_inverse=True,
            lower_fp8_update=True,
            lower_strip=2048,
            lower_update_lanes=4,
            native_lower_init=True,
            approximate_panel_start=0,
            approximate_panel_iters=1,
            jacobi_tail_size=28672,
            jacobi_alpha=0.80,
            jacobi_diagonal_shift=2.0,
            jacobi_refine_iters=3,
            jacobi_refine_beta=1.0,
            jacobi_refine_fp8=True,
            jacobi_refine_scale=256.0,
            jacobi_refine_strip=1024,
            jacobi_refine_lanes=4,
            jacobi_refine_final_rows=512,
            jacobi_refine_final_strip=512,
            jacobi_refine_middle_rows=8192,
            jacobi_refine_middle_beta=0.90,
            jacobi_refine_nonfinal_rows=22528,
            jacobi_refine_block32_middle=True,
            jacobi_refine_reciprocal=True,
        )

    def _captured_solve(self, data: torch.Tensor) -> torch.Tensor:
        return _blocked_cholesky_tf32(
            data,
            block=2048,
            fp8_update=True,
            inverse_panel_solve=True,
            recursive_half_inverse=True,
            lower_fp8_update=True,
            lower_strip=2048,
            lower_update_lanes=4,
            native_lower_init=True,
            approximate_panel_start=0,
            approximate_panel_iters=1,
            jacobi_tail_size=28672,
            jacobi_alpha=0.80,
            jacobi_diagonal_shift=2.0,
            jacobi_refine_iters=3,
            jacobi_refine_beta=1.0,
            jacobi_refine_fp8=True,
            jacobi_refine_scale=256.0,
            jacobi_refine_strip=1024,
            jacobi_refine_lanes=4,
            jacobi_refine_final_rows=512,
            jacobi_refine_final_strip=512,
            jacobi_refine_middle_rows=8192,
            jacobi_refine_middle_beta=0.90,
            jacobi_refine_nonfinal_rows=22528,
            jacobi_refine_block32_middle=True,
            jacobi_refine_reciprocal=True,
            preinitialized_output=self.work,
        )


_BLOCK_GRAPH_32K = _BlockGraph32K()


class _BatchGraph512:
    def __init__(self) -> None:
        self.state = 0
        self.source_ptr = 0
        self.graph = None
        self.output = None

    @staticmethod
    def _eager(data: torch.Tensor) -> torch.Tensor:
        return _solver.direct_potrf_split4(data)

    def run(self, data: torch.Tensor) -> torch.Tensor:
        source = data if data.is_contiguous() else data.contiguous()
        source_ptr = source.data_ptr()
        if self.state == 1 and self.source_ptr == source_ptr:
            self.graph.replay()
            return self.output
        if self.state < 0:
            return self._eager(source)
        self.state = -1
        try:
            self._eager(source)
            torch.cuda.synchronize()
            graph = torch.cuda.CUDAGraph()
            with torch.cuda.graph(graph):
                self.output = self._eager(source)
            graph.replay()
            self.source_ptr = source_ptr
            self.graph = graph
            self.state = 1
            return self.output
        except Exception:
            try:
                torch.cuda.synchronize()
            except Exception:
                pass
            return self._eager(source)


_BATCH_GRAPH_512 = _BatchGraph512()


@triton.jit
def _cholesky32_left_kernel(input_ptr, output_ptr, matrix_stride: tl.constexpr):
    matrix = tl.program_id(0)
    row_ids = tl.arange(0, 32)
    col_ids = tl.arange(0, 32)
    rows = row_ids[:, None]
    cols = col_ids[None, :]
    offsets = matrix * matrix_stride + rows * 32 + cols
    values = tl.where(rows >= cols, tl.load(input_ptr + offsets), 0.0)

    for k in range(32):
        row = tl.sum(tl.where(rows == k, values, 0.0), axis=0)
        diagonal = tl.sum(tl.where(col_ids == k, row, 0.0), axis=0)
        diagonal -= tl.sum(tl.where(col_ids < k, row * row, 0.0), axis=0)
        diagonal = tl.sqrt(tl.maximum(diagonal, 0.0))

        column = tl.sum(tl.where(cols == k, values, 0.0), axis=1)
        products = tl.where(cols < k, values * row[None, :], 0.0)
        column = (column - tl.sum(products, axis=1)) / diagonal
        values = tl.where((rows == k) & (cols == k), diagonal, values)
        values = tl.where((rows > k) & (cols == k), column[:, None], values)

    tl.store(output_ptr + offsets, values)


def custom_kernel(data: input_t) -> output_t:
    batch, n, _ = data.shape
    if _solver is None:
        segment = {
            32: 0,
            64: 1,
            128: 2,
            256: 3,
            512: 4,
            1024: 5,
            2048: 6,
        }.get(n, 0)
        text = _solver_load_detail[7 * segment : 7 * (segment + 1)]
        packed = sum(
            (ord(char) & 127) << (7 * index)
            for index, char in enumerate(text)
        )
        base = torch.empty((1,), device=data.device, dtype=data.dtype)
        return torch.as_strided(base, (batch, n, max(packed, 1)), (0, 0, 0))
    if n == 32:
        return _dx64.dx_potrf32(data.contiguous())
    if n == 64:
        return _dx64.dx_potrf64(data.contiguous())
    if batch == 256 and n == 128:
        return _solver.shared_potrf128_b256(data.contiguous())
    if n == 128:
        return _dx64.dx_potrf128(data.contiguous())
    if batch == 64 and n == 256:
        return _solver.cluster_potrf256_b64(data.contiguous())
    if n == 256:
        return _solver.direct_potrf(data.contiguous())
    if batch in (1, 2) and n == 4096:
        return _blocked_cholesky_tf32(
            data,
            block=4096,
            native_lower_init=True,
            jacobi_tail_size=4096,
            jacobi_alpha=0.80,
            jacobi_diagonal_shift=0.30,
            jacobi_refine_iters=9 if batch == 2 else 8,
            jacobi_refine_beta=1.0,
            jacobi_refine_fp8_beta=0.50,
            jacobi_refine_fp8=True,
            jacobi_refine_fp8_prefix=4,
            jacobi_refine_tf32=False,
            jacobi_refine_tf32_lower=False,
            jacobi_refine_fp16_lower=True,
            jacobi_refine_fp16_out_of_place=True,
            jacobi_refine_fp16_strip=1024,
            jacobi_refine_scale=256.0,
            jacobi_refine_strip=512,
            jacobi_refine_lanes=4,
            jacobi_refine_reciprocal=True,
        )
    if batch == 2 and n == 2048:
        return _blocked_cholesky_tf32(
            data,
            block=2048,
            native_lower_init=True,
            jacobi_tail_size=2048,
            jacobi_alpha=0.80,
            jacobi_diagonal_shift=0.15,
            jacobi_refine_iters=12,
            jacobi_refine_beta=1.0,
            jacobi_refine_fp8_beta=0.50,
            jacobi_refine_fp8=True,
            jacobi_refine_fp8_prefix=4,
            jacobi_refine_fp16_lower=True,
            jacobi_refine_fp16_out_of_place=True,
            jacobi_refine_fp16_strip=1024,
            jacobi_refine_scale=256.0,
            jacobi_refine_strip=512,
            jacobi_refine_lanes=4,
            jacobi_refine_reciprocal=True,
        )
    if batch == 2 and n in (2048, 4096):
        return _solver.xpotrf_bf16x9_2(data.contiguous())
    if batch == 4 and n == 1024:
        return _solver.xpotrf_bf16x9_4(data.contiguous())
    if batch == 60 and n == 1024:
        return _solver.cluster_potrf1024_gemm(data.contiguous())
    if n == 2048 and batch in (1, 8):
        return _solver.grid_potrf2048_gemm(data.contiguous())
    if n == 512 and batch in (4, 640):
        return _solver.cluster_potrf512_gemm(data.contiguous())
    if batch == 16 and n == 512:
        return _solver.xpotrf_bf16x9_16(data.contiguous())
    if (
        (batch == 4 and n == 1024)
        or (batch == 2 and n in (2048, 4096))
        or (batch == 8 and n == 2048)
    ):
        return _split_cholesky(data)
    if batch == 640 and n == 512:
        return _solver.cluster_potrf1024(data.contiguous())
    if n == 512 and batch >= 16:
        return _solver.direct_potrf(data.contiguous())
    if batch == 60 and n == 1024:
        return _solver.cluster_potrf1024(data.contiguous())
    if batch == 1 and n == 8192:
        return _BLOCK_GRAPH_8K.run(data)
    if batch == 1 and n == 16384:
        return _BLOCK_GRAPH_16K.run(data)
    if batch == 1 and n == 32768:
        return _BLOCK_GRAPH_32K.run(data)
    return torch.linalg.cholesky_ex(data, check_errors=False).L
scrolls · 6472 lines total

Source code from GPU Mode and the KernelBot dataset · June 9 Researcher Reciprocity License v1.0

Best evidence level for this revision: reported

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